1 /*
   2  * Copyright (c) 1999, 2024, Oracle and/or its affiliates. All rights reserved.
   3  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
   4  *
   5  * This code is free software; you can redistribute it and/or modify it
   6  * under the terms of the GNU General Public License version 2 only, as
   7  * published by the Free Software Foundation.  Oracle designates this
   8  * particular file as subject to the "Classpath" exception as provided
   9  * by Oracle in the LICENSE file that accompanied this code.
  10  *
  11  * This code is distributed in the hope that it will be useful, but WITHOUT
  12  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  13  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  14  * version 2 for more details (a copy is included in the LICENSE file that
  15  * accompanied this code).
  16  *
  17  * You should have received a copy of the GNU General Public License version
  18  * 2 along with this work; if not, write to the Free Software Foundation,
  19  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
  20  *
  21  * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
  22  * or visit www.oracle.com if you need additional information or have any
  23  * questions.
  24  */
  25 
  26 package com.sun.tools.javac.comp;
  27 
  28 import java.util.*;
  29 import java.util.function.BiConsumer;
  30 import java.util.function.Consumer;
  31 import java.util.stream.Stream;
  32 
  33 import javax.lang.model.element.ElementKind;
  34 import javax.tools.JavaFileObject;
  35 
  36 import com.sun.source.tree.CaseTree;
  37 import com.sun.source.tree.IdentifierTree;
  38 import com.sun.source.tree.MemberReferenceTree.ReferenceMode;
  39 import com.sun.source.tree.MemberSelectTree;
  40 import com.sun.source.tree.TreeVisitor;
  41 import com.sun.source.util.SimpleTreeVisitor;
  42 import com.sun.tools.javac.code.*;
  43 import com.sun.tools.javac.code.Lint.LintCategory;
  44 import com.sun.tools.javac.code.Scope.WriteableScope;
  45 import com.sun.tools.javac.code.Source.Feature;
  46 import com.sun.tools.javac.code.Symbol.*;
  47 import com.sun.tools.javac.code.Type.*;
  48 import com.sun.tools.javac.code.Types.FunctionDescriptorLookupError;
  49 import com.sun.tools.javac.comp.ArgumentAttr.LocalCacheContext;
  50 import com.sun.tools.javac.comp.Check.CheckContext;
  51 import com.sun.tools.javac.comp.DeferredAttr.AttrMode;
  52 import com.sun.tools.javac.comp.MatchBindingsComputer.MatchBindings;
  53 import com.sun.tools.javac.jvm.*;
  54 
  55 import static com.sun.tools.javac.resources.CompilerProperties.Fragments.Diamond;
  56 import static com.sun.tools.javac.resources.CompilerProperties.Fragments.DiamondInvalidArg;
  57 import static com.sun.tools.javac.resources.CompilerProperties.Fragments.DiamondInvalidArgs;
  58 
  59 import com.sun.tools.javac.resources.CompilerProperties.Errors;
  60 import com.sun.tools.javac.resources.CompilerProperties.Fragments;
  61 import com.sun.tools.javac.resources.CompilerProperties.Warnings;
  62 import com.sun.tools.javac.tree.*;
  63 import com.sun.tools.javac.tree.JCTree.*;
  64 import com.sun.tools.javac.tree.JCTree.JCPolyExpression.*;
  65 import com.sun.tools.javac.util.*;
  66 import com.sun.tools.javac.util.DefinedBy.Api;
  67 import com.sun.tools.javac.util.JCDiagnostic.DiagnosticPosition;
  68 import com.sun.tools.javac.util.JCDiagnostic.Error;
  69 import com.sun.tools.javac.util.JCDiagnostic.Fragment;
  70 import com.sun.tools.javac.util.JCDiagnostic.Warning;
  71 import com.sun.tools.javac.util.List;
  72 
  73 import static com.sun.tools.javac.code.Flags.*;
  74 import static com.sun.tools.javac.code.Flags.ANNOTATION;
  75 import static com.sun.tools.javac.code.Flags.BLOCK;
  76 import static com.sun.tools.javac.code.Kinds.*;
  77 import static com.sun.tools.javac.code.Kinds.Kind.*;
  78 import static com.sun.tools.javac.code.TypeTag.*;
  79 import static com.sun.tools.javac.code.TypeTag.WILDCARD;
  80 import static com.sun.tools.javac.tree.JCTree.Tag.*;
  81 import com.sun.tools.javac.util.JCDiagnostic.DiagnosticFlag;
  82 
  83 /** This is the main context-dependent analysis phase in GJC. It
  84  *  encompasses name resolution, type checking and constant folding as
  85  *  subtasks. Some subtasks involve auxiliary classes.
  86  *  @see Check
  87  *  @see Resolve
  88  *  @see ConstFold
  89  *  @see Infer
  90  *
  91  *  <p><b>This is NOT part of any supported API.
  92  *  If you write code that depends on this, you do so at your own risk.
  93  *  This code and its internal interfaces are subject to change or
  94  *  deletion without notice.</b>
  95  */
  96 public class Attr extends JCTree.Visitor {
  97     protected static final Context.Key<Attr> attrKey = new Context.Key<>();
  98 
  99     final Names names;
 100     final Log log;
 101     final Symtab syms;
 102     final Resolve rs;
 103     final Operators operators;
 104     final Infer infer;
 105     final Analyzer analyzer;
 106     final DeferredAttr deferredAttr;
 107     final Check chk;
 108     final Flow flow;
 109     final MemberEnter memberEnter;
 110     final TypeEnter typeEnter;
 111     final TreeMaker make;
 112     final ConstFold cfolder;
 113     final Enter enter;
 114     final Target target;
 115     final Types types;
 116     final Preview preview;
 117     final JCDiagnostic.Factory diags;
 118     final TypeAnnotations typeAnnotations;
 119     final DeferredLintHandler deferredLintHandler;
 120     final TypeEnvs typeEnvs;
 121     final Dependencies dependencies;
 122     final Annotate annotate;
 123     final ArgumentAttr argumentAttr;
 124     final MatchBindingsComputer matchBindingsComputer;
 125     final AttrRecover attrRecover;
 126 
 127     public static Attr instance(Context context) {
 128         Attr instance = context.get(attrKey);
 129         if (instance == null)
 130             instance = new Attr(context);
 131         return instance;
 132     }
 133 
 134     @SuppressWarnings("this-escape")
 135     protected Attr(Context context) {
 136         context.put(attrKey, this);
 137 
 138         names = Names.instance(context);
 139         log = Log.instance(context);
 140         syms = Symtab.instance(context);
 141         rs = Resolve.instance(context);
 142         operators = Operators.instance(context);
 143         chk = Check.instance(context);
 144         flow = Flow.instance(context);
 145         memberEnter = MemberEnter.instance(context);
 146         typeEnter = TypeEnter.instance(context);
 147         make = TreeMaker.instance(context);
 148         enter = Enter.instance(context);
 149         infer = Infer.instance(context);
 150         analyzer = Analyzer.instance(context);
 151         deferredAttr = DeferredAttr.instance(context);
 152         cfolder = ConstFold.instance(context);
 153         target = Target.instance(context);
 154         types = Types.instance(context);
 155         preview = Preview.instance(context);
 156         diags = JCDiagnostic.Factory.instance(context);
 157         annotate = Annotate.instance(context);
 158         typeAnnotations = TypeAnnotations.instance(context);
 159         deferredLintHandler = DeferredLintHandler.instance(context);
 160         typeEnvs = TypeEnvs.instance(context);
 161         dependencies = Dependencies.instance(context);
 162         argumentAttr = ArgumentAttr.instance(context);
 163         matchBindingsComputer = MatchBindingsComputer.instance(context);
 164         attrRecover = AttrRecover.instance(context);
 165 
 166         Options options = Options.instance(context);
 167 
 168         Source source = Source.instance(context);
 169         allowReifiableTypesInInstanceof = Feature.REIFIABLE_TYPES_INSTANCEOF.allowedInSource(source);
 170         allowRecords = Feature.RECORDS.allowedInSource(source);
 171         allowPatternSwitch = (preview.isEnabled() || !preview.isPreview(Feature.PATTERN_SWITCH)) &&
 172                              Feature.PATTERN_SWITCH.allowedInSource(source);
 173         allowUnconditionalPatternsInstanceOf =
 174                              Feature.UNCONDITIONAL_PATTERN_IN_INSTANCEOF.allowedInSource(source);
 175         sourceName = source.name;
 176         useBeforeDeclarationWarning = options.isSet("useBeforeDeclarationWarning");
 177 
 178         statInfo = new ResultInfo(KindSelector.NIL, Type.noType);
 179         varAssignmentInfo = new ResultInfo(KindSelector.ASG, Type.noType);
 180         unknownExprInfo = new ResultInfo(KindSelector.VAL, Type.noType);
 181         methodAttrInfo = new MethodAttrInfo();
 182         unknownTypeInfo = new ResultInfo(KindSelector.TYP, Type.noType);
 183         unknownTypeExprInfo = new ResultInfo(KindSelector.VAL_TYP, Type.noType);
 184         recoveryInfo = new RecoveryInfo(deferredAttr.emptyDeferredAttrContext);
 185     }
 186 
 187     /** Switch: reifiable types in instanceof enabled?
 188      */
 189     boolean allowReifiableTypesInInstanceof;
 190 
 191     /** Are records allowed
 192      */
 193     private final boolean allowRecords;
 194 
 195     /** Are patterns in switch allowed
 196      */
 197     private final boolean allowPatternSwitch;
 198 
 199     /** Are unconditional patterns in instanceof allowed
 200      */
 201     private final boolean allowUnconditionalPatternsInstanceOf;
 202 
 203     /**
 204      * Switch: warn about use of variable before declaration?
 205      * RFE: 6425594
 206      */
 207     boolean useBeforeDeclarationWarning;
 208 
 209     /**
 210      * Switch: name of source level; used for error reporting.
 211      */
 212     String sourceName;
 213 
 214     /** Check kind and type of given tree against protokind and prototype.
 215      *  If check succeeds, store type in tree and return it.
 216      *  If check fails, store errType in tree and return it.
 217      *  No checks are performed if the prototype is a method type.
 218      *  It is not necessary in this case since we know that kind and type
 219      *  are correct.
 220      *
 221      *  @param tree     The tree whose kind and type is checked
 222      *  @param found    The computed type of the tree
 223      *  @param ownkind  The computed kind of the tree
 224      *  @param resultInfo  The expected result of the tree
 225      */
 226     Type check(final JCTree tree,
 227                final Type found,
 228                final KindSelector ownkind,
 229                final ResultInfo resultInfo) {
 230         InferenceContext inferenceContext = resultInfo.checkContext.inferenceContext();
 231         Type owntype;
 232         boolean shouldCheck = !found.hasTag(ERROR) &&
 233                 !resultInfo.pt.hasTag(METHOD) &&
 234                 !resultInfo.pt.hasTag(FORALL);
 235         if (shouldCheck && !ownkind.subset(resultInfo.pkind)) {
 236             log.error(tree.pos(),
 237                       Errors.UnexpectedType(resultInfo.pkind.kindNames(),
 238                                             ownkind.kindNames()));
 239             owntype = types.createErrorType(found);
 240         } else if (inferenceContext.free(found)) {
 241             //delay the check if there are inference variables in the found type
 242             //this means we are dealing with a partially inferred poly expression
 243             owntype = shouldCheck ? resultInfo.pt : found;
 244             if (resultInfo.checkMode.installPostInferenceHook()) {
 245                 inferenceContext.addFreeTypeListener(List.of(found),
 246                         instantiatedContext -> {
 247                             ResultInfo pendingResult =
 248                                     resultInfo.dup(inferenceContext.asInstType(resultInfo.pt));
 249                             check(tree, inferenceContext.asInstType(found), ownkind, pendingResult);
 250                         });
 251             }
 252         } else {
 253             owntype = shouldCheck ?
 254             resultInfo.check(tree, found) :
 255             found;
 256         }
 257         if (resultInfo.checkMode.updateTreeType()) {
 258             tree.type = owntype;
 259         }
 260         return owntype;
 261     }
 262 
 263     /** Is given blank final variable assignable, i.e. in a scope where it
 264      *  may be assigned to even though it is final?
 265      *  @param v      The blank final variable.
 266      *  @param env    The current environment.
 267      */
 268     boolean isAssignableAsBlankFinal(VarSymbol v, Env<AttrContext> env) {
 269         Symbol owner = env.info.scope.owner;
 270            // owner refers to the innermost variable, method or
 271            // initializer block declaration at this point.
 272         boolean isAssignable =
 273             v.owner == owner
 274             ||
 275             ((owner.name == names.init ||    // i.e. we are in a constructor
 276               owner.kind == VAR ||           // i.e. we are in a variable initializer
 277               (owner.flags() & BLOCK) != 0)  // i.e. we are in an initializer block
 278              &&
 279              v.owner == owner.owner
 280              &&
 281              ((v.flags() & STATIC) != 0) == Resolve.isStatic(env));
 282         boolean insideCompactConstructor = env.enclMethod != null && TreeInfo.isCompactConstructor(env.enclMethod);
 283         return isAssignable & !insideCompactConstructor;
 284     }
 285 
 286     /** Check that variable can be assigned to.
 287      *  @param pos    The current source code position.
 288      *  @param v      The assigned variable
 289      *  @param base   If the variable is referred to in a Select, the part
 290      *                to the left of the `.', null otherwise.
 291      *  @param env    The current environment.
 292      */
 293     void checkAssignable(DiagnosticPosition pos, VarSymbol v, JCTree base, Env<AttrContext> env) {
 294         if (v.name == names._this) {
 295             log.error(pos, Errors.CantAssignValToThis);
 296             return;
 297         }
 298         if ((v.flags() & FINAL) != 0 &&
 299             ((v.flags() & HASINIT) != 0
 300              ||
 301              !((base == null ||
 302                TreeInfo.isThisQualifier(base)) &&
 303                isAssignableAsBlankFinal(v, env)))) {
 304             if (v.isResourceVariable()) { //TWR resource
 305                 log.error(pos, Errors.TryResourceMayNotBeAssigned(v));
 306             } else {
 307                 log.error(pos, Errors.CantAssignValToVar(Flags.toSource(v.flags() & (STATIC | FINAL)), v));
 308             }
 309             return;
 310         }
 311 
 312         // Check instance field assignments that appear in constructor prologues
 313         if (rs.isEarlyReference(env, base, v)) {
 314 
 315             // Field may not be inherited from a superclass
 316             if (v.owner != env.enclClass.sym) {
 317                 log.error(pos, Errors.CantRefBeforeCtorCalled(v));
 318                 return;
 319             }
 320 
 321             // Field may not have an initializer
 322             if ((v.flags() & HASINIT) != 0) {
 323                 log.error(pos, Errors.CantAssignInitializedBeforeCtorCalled(v));
 324                 return;
 325             }
 326         }
 327 
 328         if (!env.info.ctorPrologue &&
 329                 v.owner.isValueClass() &&
 330                 v.owner.kind == TYP &&
 331                 v.owner == env.enclClass.sym &&
 332                 (v.flags() & STATIC) == 0 &&
 333                 (base == null ||
 334                         TreeInfo.isExplicitThisReference(types, (ClassType)env.enclClass.type, base))) {
 335             log.error(pos, Errors.CantRefAfterCtorCalled(v));
 336         }
 337     }
 338 
 339     /** Does tree represent a static reference to an identifier?
 340      *  It is assumed that tree is either a SELECT or an IDENT.
 341      *  We have to weed out selects from non-type names here.
 342      *  @param tree    The candidate tree.
 343      */
 344     boolean isStaticReference(JCTree tree) {
 345         if (tree.hasTag(SELECT)) {
 346             Symbol lsym = TreeInfo.symbol(((JCFieldAccess) tree).selected);
 347             if (lsym == null || lsym.kind != TYP) {
 348                 return false;
 349             }
 350         }
 351         return true;
 352     }
 353 
 354     /** Is this symbol a type?
 355      */
 356     static boolean isType(Symbol sym) {
 357         return sym != null && sym.kind == TYP;
 358     }
 359 
 360     /** Attribute a parsed identifier.
 361      * @param tree Parsed identifier name
 362      * @param topLevel The toplevel to use
 363      */
 364     public Symbol attribIdent(JCTree tree, JCCompilationUnit topLevel) {
 365         Env<AttrContext> localEnv = enter.topLevelEnv(topLevel);
 366         localEnv.enclClass = make.ClassDef(make.Modifiers(0),
 367                                            syms.errSymbol.name,
 368                                            null, null, null, null);
 369         localEnv.enclClass.sym = syms.errSymbol;
 370         return attribIdent(tree, localEnv);
 371     }
 372 
 373     /** Attribute a parsed identifier.
 374      * @param tree Parsed identifier name
 375      * @param env The env to use
 376      */
 377     public Symbol attribIdent(JCTree tree, Env<AttrContext> env) {
 378         return tree.accept(identAttributer, env);
 379     }
 380     // where
 381         private TreeVisitor<Symbol,Env<AttrContext>> identAttributer = new IdentAttributer();
 382         private class IdentAttributer extends SimpleTreeVisitor<Symbol,Env<AttrContext>> {
 383             @Override @DefinedBy(Api.COMPILER_TREE)
 384             public Symbol visitMemberSelect(MemberSelectTree node, Env<AttrContext> env) {
 385                 Symbol site = visit(node.getExpression(), env);
 386                 if (site.kind == ERR || site.kind == ABSENT_TYP || site.kind == HIDDEN)
 387                     return site;
 388                 Name name = (Name)node.getIdentifier();
 389                 if (site.kind == PCK) {
 390                     env.toplevel.packge = (PackageSymbol)site;
 391                     return rs.findIdentInPackage(null, env, (TypeSymbol)site, name,
 392                             KindSelector.TYP_PCK);
 393                 } else {
 394                     env.enclClass.sym = (ClassSymbol)site;
 395                     return rs.findMemberType(env, site.asType(), name, (TypeSymbol)site);
 396                 }
 397             }
 398 
 399             @Override @DefinedBy(Api.COMPILER_TREE)
 400             public Symbol visitIdentifier(IdentifierTree node, Env<AttrContext> env) {
 401                 return rs.findIdent(null, env, (Name)node.getName(), KindSelector.TYP_PCK);
 402             }
 403         }
 404 
 405     public Type coerce(Type etype, Type ttype) {
 406         return cfolder.coerce(etype, ttype);
 407     }
 408 
 409     public Type attribType(JCTree node, TypeSymbol sym) {
 410         Env<AttrContext> env = typeEnvs.get(sym);
 411         Env<AttrContext> localEnv = env.dup(node, env.info.dup());
 412         return attribTree(node, localEnv, unknownTypeInfo);
 413     }
 414 
 415     public Type attribImportQualifier(JCImport tree, Env<AttrContext> env) {
 416         // Attribute qualifying package or class.
 417         JCFieldAccess s = tree.qualid;
 418         return attribTree(s.selected, env,
 419                           new ResultInfo(tree.staticImport ?
 420                                          KindSelector.TYP : KindSelector.TYP_PCK,
 421                        Type.noType));
 422     }
 423 
 424     public Env<AttrContext> attribExprToTree(JCTree expr, Env<AttrContext> env, JCTree tree) {
 425         return attribToTree(expr, env, tree, unknownExprInfo);
 426     }
 427 
 428     public Env<AttrContext> attribStatToTree(JCTree stmt, Env<AttrContext> env, JCTree tree) {
 429         return attribToTree(stmt, env, tree, statInfo);
 430     }
 431 
 432     private Env<AttrContext> attribToTree(JCTree root, Env<AttrContext> env, JCTree tree, ResultInfo resultInfo) {
 433         breakTree = tree;
 434         JavaFileObject prev = log.useSource(env.toplevel.sourcefile);
 435         try {
 436             deferredAttr.attribSpeculative(root, env, resultInfo,
 437                     null, DeferredAttr.AttributionMode.ATTRIB_TO_TREE,
 438                     argumentAttr.withLocalCacheContext());
 439             attrRecover.doRecovery();
 440         } catch (BreakAttr b) {
 441             return b.env;
 442         } catch (AssertionError ae) {
 443             if (ae.getCause() instanceof BreakAttr breakAttr) {
 444                 return breakAttr.env;
 445             } else {
 446                 throw ae;
 447             }
 448         } finally {
 449             breakTree = null;
 450             log.useSource(prev);
 451         }
 452         return env;
 453     }
 454 
 455     private JCTree breakTree = null;
 456 
 457     private static class BreakAttr extends RuntimeException {
 458         static final long serialVersionUID = -6924771130405446405L;
 459         private transient Env<AttrContext> env;
 460         private BreakAttr(Env<AttrContext> env) {
 461             this.env = env;
 462         }
 463     }
 464 
 465     /**
 466      * Mode controlling behavior of Attr.Check
 467      */
 468     enum CheckMode {
 469 
 470         NORMAL,
 471 
 472         /**
 473          * Mode signalling 'fake check' - skip tree update. A side-effect of this mode is
 474          * that the captured var cache in {@code InferenceContext} will be used in read-only
 475          * mode when performing inference checks.
 476          */
 477         NO_TREE_UPDATE {
 478             @Override
 479             public boolean updateTreeType() {
 480                 return false;
 481             }
 482         },
 483         /**
 484          * Mode signalling that caller will manage free types in tree decorations.
 485          */
 486         NO_INFERENCE_HOOK {
 487             @Override
 488             public boolean installPostInferenceHook() {
 489                 return false;
 490             }
 491         };
 492 
 493         public boolean updateTreeType() {
 494             return true;
 495         }
 496         public boolean installPostInferenceHook() {
 497             return true;
 498         }
 499     }
 500 
 501 
 502     class ResultInfo {
 503         final KindSelector pkind;
 504         final Type pt;
 505         final CheckContext checkContext;
 506         final CheckMode checkMode;
 507 
 508         ResultInfo(KindSelector pkind, Type pt) {
 509             this(pkind, pt, chk.basicHandler, CheckMode.NORMAL);
 510         }
 511 
 512         ResultInfo(KindSelector pkind, Type pt, CheckMode checkMode) {
 513             this(pkind, pt, chk.basicHandler, checkMode);
 514         }
 515 
 516         protected ResultInfo(KindSelector pkind,
 517                              Type pt, CheckContext checkContext) {
 518             this(pkind, pt, checkContext, CheckMode.NORMAL);
 519         }
 520 
 521         protected ResultInfo(KindSelector pkind,
 522                              Type pt, CheckContext checkContext, CheckMode checkMode) {
 523             this.pkind = pkind;
 524             this.pt = pt;
 525             this.checkContext = checkContext;
 526             this.checkMode = checkMode;
 527         }
 528 
 529         /**
 530          * Should {@link Attr#attribTree} use the {@code ArgumentAttr} visitor instead of this one?
 531          * @param tree The tree to be type-checked.
 532          * @return true if {@code ArgumentAttr} should be used.
 533          */
 534         protected boolean needsArgumentAttr(JCTree tree) { return false; }
 535 
 536         protected Type check(final DiagnosticPosition pos, final Type found) {
 537             return chk.checkType(pos, found, pt, checkContext);
 538         }
 539 
 540         protected ResultInfo dup(Type newPt) {
 541             return new ResultInfo(pkind, newPt, checkContext, checkMode);
 542         }
 543 
 544         protected ResultInfo dup(CheckContext newContext) {
 545             return new ResultInfo(pkind, pt, newContext, checkMode);
 546         }
 547 
 548         protected ResultInfo dup(Type newPt, CheckContext newContext) {
 549             return new ResultInfo(pkind, newPt, newContext, checkMode);
 550         }
 551 
 552         protected ResultInfo dup(Type newPt, CheckContext newContext, CheckMode newMode) {
 553             return new ResultInfo(pkind, newPt, newContext, newMode);
 554         }
 555 
 556         protected ResultInfo dup(CheckMode newMode) {
 557             return new ResultInfo(pkind, pt, checkContext, newMode);
 558         }
 559 
 560         @Override
 561         public String toString() {
 562             if (pt != null) {
 563                 return pt.toString();
 564             } else {
 565                 return "";
 566             }
 567         }
 568     }
 569 
 570     class MethodAttrInfo extends ResultInfo {
 571         public MethodAttrInfo() {
 572             this(chk.basicHandler);
 573         }
 574 
 575         public MethodAttrInfo(CheckContext checkContext) {
 576             super(KindSelector.VAL, Infer.anyPoly, checkContext);
 577         }
 578 
 579         @Override
 580         protected boolean needsArgumentAttr(JCTree tree) {
 581             return true;
 582         }
 583 
 584         protected ResultInfo dup(Type newPt) {
 585             throw new IllegalStateException();
 586         }
 587 
 588         protected ResultInfo dup(CheckContext newContext) {
 589             return new MethodAttrInfo(newContext);
 590         }
 591 
 592         protected ResultInfo dup(Type newPt, CheckContext newContext) {
 593             throw new IllegalStateException();
 594         }
 595 
 596         protected ResultInfo dup(Type newPt, CheckContext newContext, CheckMode newMode) {
 597             throw new IllegalStateException();
 598         }
 599 
 600         protected ResultInfo dup(CheckMode newMode) {
 601             throw new IllegalStateException();
 602         }
 603     }
 604 
 605     class RecoveryInfo extends ResultInfo {
 606 
 607         public RecoveryInfo(final DeferredAttr.DeferredAttrContext deferredAttrContext) {
 608             this(deferredAttrContext, Type.recoveryType);
 609         }
 610 
 611         public RecoveryInfo(final DeferredAttr.DeferredAttrContext deferredAttrContext, Type pt) {
 612             super(KindSelector.VAL, pt, new Check.NestedCheckContext(chk.basicHandler) {
 613                 @Override
 614                 public DeferredAttr.DeferredAttrContext deferredAttrContext() {
 615                     return deferredAttrContext;
 616                 }
 617                 @Override
 618                 public boolean compatible(Type found, Type req, Warner warn) {
 619                     return true;
 620                 }
 621                 @Override
 622                 public void report(DiagnosticPosition pos, JCDiagnostic details) {
 623                     boolean needsReport = pt == Type.recoveryType ||
 624                             (details.getDiagnosticPosition() != null &&
 625                             details.getDiagnosticPosition().getTree().hasTag(LAMBDA));
 626                     if (needsReport) {
 627                         chk.basicHandler.report(pos, details);
 628                     }
 629                 }
 630             });
 631         }
 632     }
 633 
 634     final ResultInfo statInfo;
 635     final ResultInfo varAssignmentInfo;
 636     final ResultInfo methodAttrInfo;
 637     final ResultInfo unknownExprInfo;
 638     final ResultInfo unknownTypeInfo;
 639     final ResultInfo unknownTypeExprInfo;
 640     final ResultInfo recoveryInfo;
 641 
 642     Type pt() {
 643         return resultInfo.pt;
 644     }
 645 
 646     KindSelector pkind() {
 647         return resultInfo.pkind;
 648     }
 649 
 650 /* ************************************************************************
 651  * Visitor methods
 652  *************************************************************************/
 653 
 654     /** Visitor argument: the current environment.
 655      */
 656     Env<AttrContext> env;
 657 
 658     /** Visitor argument: the currently expected attribution result.
 659      */
 660     ResultInfo resultInfo;
 661 
 662     /** Visitor result: the computed type.
 663      */
 664     Type result;
 665 
 666     MatchBindings matchBindings = MatchBindingsComputer.EMPTY;
 667 
 668     /** Visitor method: attribute a tree, catching any completion failure
 669      *  exceptions. Return the tree's type.
 670      *
 671      *  @param tree    The tree to be visited.
 672      *  @param env     The environment visitor argument.
 673      *  @param resultInfo   The result info visitor argument.
 674      */
 675     Type attribTree(JCTree tree, Env<AttrContext> env, ResultInfo resultInfo) {
 676         Env<AttrContext> prevEnv = this.env;
 677         ResultInfo prevResult = this.resultInfo;
 678         try {
 679             this.env = env;
 680             this.resultInfo = resultInfo;
 681             if (resultInfo.needsArgumentAttr(tree)) {
 682                 result = argumentAttr.attribArg(tree, env);
 683             } else {
 684                 tree.accept(this);
 685             }
 686             matchBindings = matchBindingsComputer.finishBindings(tree,
 687                                                                  matchBindings);
 688             if (tree == breakTree &&
 689                     resultInfo.checkContext.deferredAttrContext().mode == AttrMode.CHECK) {
 690                 breakTreeFound(copyEnv(env));
 691             }
 692             return result;
 693         } catch (CompletionFailure ex) {
 694             tree.type = syms.errType;
 695             return chk.completionError(tree.pos(), ex);
 696         } finally {
 697             this.env = prevEnv;
 698             this.resultInfo = prevResult;
 699         }
 700     }
 701 
 702     protected void breakTreeFound(Env<AttrContext> env) {
 703         throw new BreakAttr(env);
 704     }
 705 
 706     Env<AttrContext> copyEnv(Env<AttrContext> env) {
 707         Env<AttrContext> newEnv =
 708                 env.dup(env.tree, env.info.dup(copyScope(env.info.scope)));
 709         if (newEnv.outer != null) {
 710             newEnv.outer = copyEnv(newEnv.outer);
 711         }
 712         return newEnv;
 713     }
 714 
 715     WriteableScope copyScope(WriteableScope sc) {
 716         WriteableScope newScope = WriteableScope.create(sc.owner);
 717         List<Symbol> elemsList = List.nil();
 718         for (Symbol sym : sc.getSymbols()) {
 719             elemsList = elemsList.prepend(sym);
 720         }
 721         for (Symbol s : elemsList) {
 722             newScope.enter(s);
 723         }
 724         return newScope;
 725     }
 726 
 727     /** Derived visitor method: attribute an expression tree.
 728      */
 729     public Type attribExpr(JCTree tree, Env<AttrContext> env, Type pt) {
 730         return attribTree(tree, env, new ResultInfo(KindSelector.VAL, !pt.hasTag(ERROR) ? pt : Type.noType));
 731     }
 732 
 733     /** Derived visitor method: attribute an expression tree with
 734      *  no constraints on the computed type.
 735      */
 736     public Type attribExpr(JCTree tree, Env<AttrContext> env) {
 737         return attribTree(tree, env, unknownExprInfo);
 738     }
 739 
 740     /** Derived visitor method: attribute a type tree.
 741      */
 742     public Type attribType(JCTree tree, Env<AttrContext> env) {
 743         Type result = attribType(tree, env, Type.noType);
 744         return result;
 745     }
 746 
 747     /** Derived visitor method: attribute a type tree.
 748      */
 749     Type attribType(JCTree tree, Env<AttrContext> env, Type pt) {
 750         Type result = attribTree(tree, env, new ResultInfo(KindSelector.TYP, pt));
 751         return result;
 752     }
 753 
 754     /** Derived visitor method: attribute a statement or definition tree.
 755      */
 756     public Type attribStat(JCTree tree, Env<AttrContext> env) {
 757         Env<AttrContext> analyzeEnv = analyzer.copyEnvIfNeeded(tree, env);
 758         Type result = attribTree(tree, env, statInfo);
 759         analyzer.analyzeIfNeeded(tree, analyzeEnv);
 760         attrRecover.doRecovery();
 761         return result;
 762     }
 763 
 764     /** Attribute a list of expressions, returning a list of types.
 765      */
 766     List<Type> attribExprs(List<JCExpression> trees, Env<AttrContext> env, Type pt) {
 767         ListBuffer<Type> ts = new ListBuffer<>();
 768         for (List<JCExpression> l = trees; l.nonEmpty(); l = l.tail)
 769             ts.append(attribExpr(l.head, env, pt));
 770         return ts.toList();
 771     }
 772 
 773     /** Attribute a list of statements, returning nothing.
 774      */
 775     <T extends JCTree> void attribStats(List<T> trees, Env<AttrContext> env) {
 776         for (List<T> l = trees; l.nonEmpty(); l = l.tail)
 777             attribStat(l.head, env);
 778     }
 779 
 780     /** Attribute the arguments in a method call, returning the method kind.
 781      */
 782     KindSelector attribArgs(KindSelector initialKind, List<JCExpression> trees, Env<AttrContext> env, ListBuffer<Type> argtypes) {
 783         KindSelector kind = initialKind;
 784         for (JCExpression arg : trees) {
 785             Type argtype = chk.checkNonVoid(arg, attribTree(arg, env, methodAttrInfo));
 786             if (argtype.hasTag(DEFERRED)) {
 787                 kind = KindSelector.of(KindSelector.POLY, kind);
 788             }
 789             argtypes.append(argtype);
 790         }
 791         return kind;
 792     }
 793 
 794     /** Attribute a type argument list, returning a list of types.
 795      *  Caller is responsible for calling checkRefTypes.
 796      */
 797     List<Type> attribAnyTypes(List<JCExpression> trees, Env<AttrContext> env) {
 798         ListBuffer<Type> argtypes = new ListBuffer<>();
 799         for (List<JCExpression> l = trees; l.nonEmpty(); l = l.tail)
 800             argtypes.append(attribType(l.head, env));
 801         return argtypes.toList();
 802     }
 803 
 804     /** Attribute a type argument list, returning a list of types.
 805      *  Check that all the types are references.
 806      */
 807     List<Type> attribTypes(List<JCExpression> trees, Env<AttrContext> env) {
 808         List<Type> types = attribAnyTypes(trees, env);
 809         return chk.checkRefTypes(trees, types);
 810     }
 811 
 812     /**
 813      * Attribute type variables (of generic classes or methods).
 814      * Compound types are attributed later in attribBounds.
 815      * @param typarams the type variables to enter
 816      * @param env      the current environment
 817      */
 818     void attribTypeVariables(List<JCTypeParameter> typarams, Env<AttrContext> env, boolean checkCyclic) {
 819         for (JCTypeParameter tvar : typarams) {
 820             TypeVar a = (TypeVar)tvar.type;
 821             a.tsym.flags_field |= UNATTRIBUTED;
 822             a.setUpperBound(Type.noType);
 823             if (!tvar.bounds.isEmpty()) {
 824                 List<Type> bounds = List.of(attribType(tvar.bounds.head, env));
 825                 for (JCExpression bound : tvar.bounds.tail)
 826                     bounds = bounds.prepend(attribType(bound, env));
 827                 types.setBounds(a, bounds.reverse());
 828             } else {
 829                 // if no bounds are given, assume a single bound of
 830                 // java.lang.Object.
 831                 types.setBounds(a, List.of(syms.objectType));
 832             }
 833             a.tsym.flags_field &= ~UNATTRIBUTED;
 834         }
 835         if (checkCyclic) {
 836             for (JCTypeParameter tvar : typarams) {
 837                 chk.checkNonCyclic(tvar.pos(), (TypeVar)tvar.type);
 838             }
 839         }
 840     }
 841 
 842     /**
 843      * Attribute the type references in a list of annotations.
 844      */
 845     void attribAnnotationTypes(List<JCAnnotation> annotations,
 846                                Env<AttrContext> env) {
 847         for (List<JCAnnotation> al = annotations; al.nonEmpty(); al = al.tail) {
 848             JCAnnotation a = al.head;
 849             attribType(a.annotationType, env);
 850         }
 851     }
 852 
 853     /**
 854      * Attribute a "lazy constant value".
 855      *  @param env         The env for the const value
 856      *  @param variable    The initializer for the const value
 857      *  @param type        The expected type, or null
 858      *  @see VarSymbol#setLazyConstValue
 859      */
 860     public Object attribLazyConstantValue(Env<AttrContext> env,
 861                                       JCVariableDecl variable,
 862                                       Type type) {
 863 
 864         DiagnosticPosition prevLintPos
 865                 = deferredLintHandler.setPos(variable.pos());
 866 
 867         final JavaFileObject prevSource = log.useSource(env.toplevel.sourcefile);
 868         try {
 869             Type itype = attribExpr(variable.init, env, type);
 870             if (variable.isImplicitlyTyped()) {
 871                 //fixup local variable type
 872                 type = variable.type = variable.sym.type = chk.checkLocalVarType(variable, itype, variable.name);
 873             }
 874             if (itype.constValue() != null) {
 875                 return coerce(itype, type).constValue();
 876             } else {
 877                 return null;
 878             }
 879         } finally {
 880             log.useSource(prevSource);
 881             deferredLintHandler.setPos(prevLintPos);
 882         }
 883     }
 884 
 885     /** Attribute type reference in an `extends' or `implements' clause.
 886      *  Supertypes of anonymous inner classes are usually already attributed.
 887      *
 888      *  @param tree              The tree making up the type reference.
 889      *  @param env               The environment current at the reference.
 890      *  @param classExpected     true if only a class is expected here.
 891      *  @param interfaceExpected true if only an interface is expected here.
 892      */
 893     Type attribBase(JCTree tree,
 894                     Env<AttrContext> env,
 895                     boolean classExpected,
 896                     boolean interfaceExpected,
 897                     boolean checkExtensible) {
 898         Type t = tree.type != null ?
 899             tree.type :
 900             attribType(tree, env);
 901         try {
 902             return checkBase(t, tree, env, classExpected, interfaceExpected, checkExtensible);
 903         } catch (CompletionFailure ex) {
 904             chk.completionError(tree.pos(), ex);
 905             return t;
 906         }
 907     }
 908     Type checkBase(Type t,
 909                    JCTree tree,
 910                    Env<AttrContext> env,
 911                    boolean classExpected,
 912                    boolean interfaceExpected,
 913                    boolean checkExtensible) {
 914         final DiagnosticPosition pos = tree.hasTag(TYPEAPPLY) ?
 915                 (((JCTypeApply) tree).clazz).pos() : tree.pos();
 916         if (t.tsym.isAnonymous()) {
 917             log.error(pos, Errors.CantInheritFromAnon);
 918             return types.createErrorType(t);
 919         }
 920         if (t.isErroneous())
 921             return t;
 922         if (t.hasTag(TYPEVAR) && !classExpected && !interfaceExpected) {
 923             // check that type variable is already visible
 924             if (t.getUpperBound() == null) {
 925                 log.error(pos, Errors.IllegalForwardRef);
 926                 return types.createErrorType(t);
 927             }
 928         } else {
 929             t = chk.checkClassType(pos, t, checkExtensible);
 930         }
 931         if (interfaceExpected && (t.tsym.flags() & INTERFACE) == 0) {
 932             log.error(pos, Errors.IntfExpectedHere);
 933             // return errType is necessary since otherwise there might
 934             // be undetected cycles which cause attribution to loop
 935             return types.createErrorType(t);
 936         } else if (checkExtensible &&
 937                    classExpected &&
 938                    (t.tsym.flags() & INTERFACE) != 0) {
 939             log.error(pos, Errors.NoIntfExpectedHere);
 940             return types.createErrorType(t);
 941         }
 942         if (checkExtensible &&
 943             ((t.tsym.flags() & FINAL) != 0)) {
 944             log.error(pos,
 945                       Errors.CantInheritFromFinal(t.tsym));
 946         }
 947         chk.checkNonCyclic(pos, t);
 948         return t;
 949     }
 950 
 951     Type attribIdentAsEnumType(Env<AttrContext> env, JCIdent id) {
 952         Assert.check((env.enclClass.sym.flags() & ENUM) != 0);
 953         id.type = env.info.scope.owner.enclClass().type;
 954         id.sym = env.info.scope.owner.enclClass();
 955         return id.type;
 956     }
 957 
 958     public void visitClassDef(JCClassDecl tree) {
 959         Optional<ArgumentAttr.LocalCacheContext> localCacheContext =
 960                 Optional.ofNullable(env.info.attributionMode.isSpeculative ?
 961                         argumentAttr.withLocalCacheContext() : null);
 962         boolean ctorProloguePrev = env.info.ctorPrologue;
 963         try {
 964             // Local and anonymous classes have not been entered yet, so we need to
 965             // do it now.
 966             if (env.info.scope.owner.kind.matches(KindSelector.VAL_MTH)) {
 967                 enter.classEnter(tree, env);
 968             } else {
 969                 // If this class declaration is part of a class level annotation,
 970                 // as in @MyAnno(new Object() {}) class MyClass {}, enter it in
 971                 // order to simplify later steps and allow for sensible error
 972                 // messages.
 973                 if (env.tree.hasTag(NEWCLASS) && TreeInfo.isInAnnotation(env, tree))
 974                     enter.classEnter(tree, env);
 975             }
 976 
 977             ClassSymbol c = tree.sym;
 978             if (c == null) {
 979                 // exit in case something drastic went wrong during enter.
 980                 result = null;
 981             } else {
 982                 // make sure class has been completed:
 983                 c.complete();
 984 
 985                 // If a class declaration appears in a constructor prologue,
 986                 // that means it's either a local class or an anonymous class.
 987                 // Either way, there is no immediately enclosing instance.
 988                 if (ctorProloguePrev) {
 989                     c.flags_field |= NOOUTERTHIS;
 990                 }
 991                 attribClass(tree.pos(), c);
 992                 result = tree.type = c.type;
 993             }
 994         } finally {
 995             localCacheContext.ifPresent(LocalCacheContext::leave);
 996             env.info.ctorPrologue = ctorProloguePrev;
 997         }
 998     }
 999 
1000     public void visitMethodDef(JCMethodDecl tree) {
1001         MethodSymbol m = tree.sym;
1002         boolean isDefaultMethod = (m.flags() & DEFAULT) != 0;
1003 
1004         Lint lint = env.info.lint.augment(m);
1005         Lint prevLint = chk.setLint(lint);
1006         boolean ctorProloguePrev = env.info.ctorPrologue;
1007         Assert.check(!env.info.ctorPrologue);
1008         MethodSymbol prevMethod = chk.setMethod(m);
1009         try {
1010             deferredLintHandler.flush(tree.pos(), lint);
1011             chk.checkDeprecatedAnnotation(tree.pos(), m);
1012 
1013 
1014             // Create a new environment with local scope
1015             // for attributing the method.
1016             Env<AttrContext> localEnv = memberEnter.methodEnv(tree, env);
1017             localEnv.info.lint = lint;
1018 
1019             attribStats(tree.typarams, localEnv);
1020 
1021             // If we override any other methods, check that we do so properly.
1022             // JLS ???
1023             if (m.isStatic()) {
1024                 chk.checkHideClashes(tree.pos(), env.enclClass.type, m);
1025             } else {
1026                 chk.checkOverrideClashes(tree.pos(), env.enclClass.type, m);
1027             }
1028             chk.checkOverride(env, tree, m);
1029 
1030             if (isDefaultMethod && types.overridesObjectMethod(m.enclClass(), m)) {
1031                 log.error(tree, Errors.DefaultOverridesObjectMember(m.name, Kinds.kindName(m.location()), m.location()));
1032             }
1033 
1034             // Enter all type parameters into the local method scope.
1035             for (List<JCTypeParameter> l = tree.typarams; l.nonEmpty(); l = l.tail)
1036                 localEnv.info.scope.enterIfAbsent(l.head.type.tsym);
1037 
1038             ClassSymbol owner = env.enclClass.sym;
1039             if ((owner.flags() & ANNOTATION) != 0 &&
1040                     (tree.params.nonEmpty() ||
1041                     tree.recvparam != null))
1042                 log.error(tree.params.nonEmpty() ?
1043                         tree.params.head.pos() :
1044                         tree.recvparam.pos(),
1045                         Errors.IntfAnnotationMembersCantHaveParams);
1046 
1047             // Attribute all value parameters.
1048             for (List<JCVariableDecl> l = tree.params; l.nonEmpty(); l = l.tail) {
1049                 attribStat(l.head, localEnv);
1050             }
1051 
1052             chk.checkVarargsMethodDecl(localEnv, tree);
1053 
1054             // Check that type parameters are well-formed.
1055             chk.validate(tree.typarams, localEnv);
1056 
1057             // Check that result type is well-formed.
1058             if (tree.restype != null && !tree.restype.type.hasTag(VOID))
1059                 chk.validate(tree.restype, localEnv);
1060 
1061             // Check that receiver type is well-formed.
1062             if (tree.recvparam != null) {
1063                 // Use a new environment to check the receiver parameter.
1064                 // Otherwise I get "might not have been initialized" errors.
1065                 // Is there a better way?
1066                 Env<AttrContext> newEnv = memberEnter.methodEnv(tree, env);
1067                 attribType(tree.recvparam, newEnv);
1068                 chk.validate(tree.recvparam, newEnv);
1069             }
1070 
1071             // Is this method a constructor?
1072             boolean isConstructor = TreeInfo.isConstructor(tree);
1073 
1074             if (env.enclClass.sym.isRecord() && tree.sym.owner.kind == TYP) {
1075                 // lets find if this method is an accessor
1076                 Optional<? extends RecordComponent> recordComponent = env.enclClass.sym.getRecordComponents().stream()
1077                         .filter(rc -> rc.accessor == tree.sym && (rc.accessor.flags_field & GENERATED_MEMBER) == 0).findFirst();
1078                 if (recordComponent.isPresent()) {
1079                     // the method is a user defined accessor lets check that everything is fine
1080                     if (!tree.sym.isPublic()) {
1081                         log.error(tree, Errors.InvalidAccessorMethodInRecord(env.enclClass.sym, Fragments.MethodMustBePublic));
1082                     }
1083                     if (!types.isSameType(tree.sym.type.getReturnType(), recordComponent.get().type)) {
1084                         log.error(tree, Errors.InvalidAccessorMethodInRecord(env.enclClass.sym,
1085                                 Fragments.AccessorReturnTypeDoesntMatch(tree.sym, recordComponent.get())));
1086                     }
1087                     if (tree.sym.type.asMethodType().thrown != null && !tree.sym.type.asMethodType().thrown.isEmpty()) {
1088                         log.error(tree,
1089                                 Errors.InvalidAccessorMethodInRecord(env.enclClass.sym, Fragments.AccessorMethodCantThrowException));
1090                     }
1091                     if (!tree.typarams.isEmpty()) {
1092                         log.error(tree,
1093                                 Errors.InvalidAccessorMethodInRecord(env.enclClass.sym, Fragments.AccessorMethodMustNotBeGeneric));
1094                     }
1095                     if (tree.sym.isStatic()) {
1096                         log.error(tree,
1097                                 Errors.InvalidAccessorMethodInRecord(env.enclClass.sym, Fragments.AccessorMethodMustNotBeStatic));
1098                     }
1099                 }
1100 
1101                 if (isConstructor) {
1102                     // if this a constructor other than the canonical one
1103                     if ((tree.sym.flags_field & RECORD) == 0) {
1104                         if (!TreeInfo.hasConstructorCall(tree, names._this)) {
1105                             log.error(tree, Errors.NonCanonicalConstructorInvokeAnotherConstructor(env.enclClass.sym));
1106                         }
1107                     } else {
1108                         // but if it is the canonical:
1109 
1110                         /* if user generated, then it shouldn't:
1111                          *     - have an accessibility stricter than that of the record type
1112                          *     - explicitly invoke any other constructor
1113                          */
1114                         if ((tree.sym.flags_field & GENERATEDCONSTR) == 0) {
1115                             if (Check.protection(m.flags()) > Check.protection(env.enclClass.sym.flags())) {
1116                                 log.error(tree,
1117                                         (env.enclClass.sym.flags() & AccessFlags) == 0 ?
1118                                             Errors.InvalidCanonicalConstructorInRecord(
1119                                                 Fragments.Canonical,
1120                                                 env.enclClass.sym.name,
1121                                                 Fragments.CanonicalMustNotHaveStrongerAccess("package")
1122                                             ) :
1123                                             Errors.InvalidCanonicalConstructorInRecord(
1124                                                     Fragments.Canonical,
1125                                                     env.enclClass.sym.name,
1126                                                     Fragments.CanonicalMustNotHaveStrongerAccess(asFlagSet(env.enclClass.sym.flags() & AccessFlags))
1127                                             )
1128                                 );
1129                             }
1130 
1131                             if (TreeInfo.hasAnyConstructorCall(tree)) {
1132                                 log.error(tree, Errors.InvalidCanonicalConstructorInRecord(
1133                                         Fragments.Canonical, env.enclClass.sym.name,
1134                                         Fragments.CanonicalMustNotContainExplicitConstructorInvocation));
1135                             }
1136                         }
1137 
1138                         // also we want to check that no type variables have been defined
1139                         if (!tree.typarams.isEmpty()) {
1140                             log.error(tree, Errors.InvalidCanonicalConstructorInRecord(
1141                                     Fragments.Canonical, env.enclClass.sym.name, Fragments.CanonicalMustNotDeclareTypeVariables));
1142                         }
1143 
1144                         /* and now we need to check that the constructor's arguments are exactly the same as those of the
1145                          * record components
1146                          */
1147                         List<? extends RecordComponent> recordComponents = env.enclClass.sym.getRecordComponents();
1148                         List<Type> recordFieldTypes = TreeInfo.recordFields(env.enclClass).map(vd -> vd.sym.type);
1149                         for (JCVariableDecl param: tree.params) {
1150                             boolean paramIsVarArgs = (param.sym.flags_field & VARARGS) != 0;
1151                             if (!types.isSameType(param.type, recordFieldTypes.head) ||
1152                                     (recordComponents.head.isVarargs() != paramIsVarArgs)) {
1153                                 log.error(param, Errors.InvalidCanonicalConstructorInRecord(
1154                                         Fragments.Canonical, env.enclClass.sym.name,
1155                                         Fragments.TypeMustBeIdenticalToCorrespondingRecordComponentType));
1156                             }
1157                             recordComponents = recordComponents.tail;
1158                             recordFieldTypes = recordFieldTypes.tail;
1159                         }
1160                     }
1161                 }
1162             }
1163 
1164             // annotation method checks
1165             if ((owner.flags() & ANNOTATION) != 0) {
1166                 // annotation method cannot have throws clause
1167                 if (tree.thrown.nonEmpty()) {
1168                     log.error(tree.thrown.head.pos(),
1169                               Errors.ThrowsNotAllowedInIntfAnnotation);
1170                 }
1171                 // annotation method cannot declare type-parameters
1172                 if (tree.typarams.nonEmpty()) {
1173                     log.error(tree.typarams.head.pos(),
1174                               Errors.IntfAnnotationMembersCantHaveTypeParams);
1175                 }
1176                 // validate annotation method's return type (could be an annotation type)
1177                 chk.validateAnnotationType(tree.restype);
1178                 // ensure that annotation method does not clash with members of Object/Annotation
1179                 chk.validateAnnotationMethod(tree.pos(), m);
1180             }
1181 
1182             for (List<JCExpression> l = tree.thrown; l.nonEmpty(); l = l.tail)
1183                 chk.checkType(l.head.pos(), l.head.type, syms.throwableType);
1184 
1185             if (tree.body == null) {
1186                 // Empty bodies are only allowed for
1187                 // abstract, native, or interface methods, or for methods
1188                 // in a retrofit signature class.
1189                 if (tree.defaultValue != null) {
1190                     if ((owner.flags() & ANNOTATION) == 0)
1191                         log.error(tree.pos(),
1192                                   Errors.DefaultAllowedInIntfAnnotationMember);
1193                 }
1194                 if (isDefaultMethod || (tree.sym.flags() & (ABSTRACT | NATIVE)) == 0)
1195                     log.error(tree.pos(), Errors.MissingMethBodyOrDeclAbstract);
1196             } else {
1197                 if ((tree.sym.flags() & (ABSTRACT|DEFAULT|PRIVATE)) == ABSTRACT) {
1198                     if ((owner.flags() & INTERFACE) != 0) {
1199                         log.error(tree.body.pos(), Errors.IntfMethCantHaveBody);
1200                     } else {
1201                         log.error(tree.pos(), Errors.AbstractMethCantHaveBody);
1202                     }
1203                 } else if ((tree.mods.flags & NATIVE) != 0) {
1204                     log.error(tree.pos(), Errors.NativeMethCantHaveBody);
1205                 }
1206                 // Add an implicit super() call unless an explicit call to
1207                 // super(...) or this(...) is given
1208                 // or we are compiling class java.lang.Object.
1209                 if (isConstructor && owner.type != syms.objectType) {
1210                     if (!TreeInfo.hasAnyConstructorCall(tree)) {
1211                         JCStatement supCall = make.at(tree.body.pos).Exec(make.Apply(List.nil(),
1212                                 make.Ident(names._super), make.Idents(List.nil())));
1213                         if (owner.isValueClass()) {
1214                             tree.body.stats = tree.body.stats.append(supCall);
1215                         } else {
1216                             tree.body.stats = tree.body.stats.prepend(supCall);
1217                         }
1218                     } else if ((env.enclClass.sym.flags() & ENUM) != 0 &&
1219                             (tree.mods.flags & GENERATEDCONSTR) == 0 &&
1220                             TreeInfo.hasConstructorCall(tree, names._super)) {
1221                         // enum constructors are not allowed to call super
1222                         // directly, so make sure there aren't any super calls
1223                         // in enum constructors, except in the compiler
1224                         // generated one.
1225                         log.error(tree.body.stats.head.pos(),
1226                                   Errors.CallToSuperNotAllowedInEnumCtor(env.enclClass.sym));
1227                     }
1228                     if (env.enclClass.sym.isRecord() && (tree.sym.flags_field & RECORD) != 0) { // we are seeing the canonical constructor
1229                         List<Name> recordComponentNames = TreeInfo.recordFields(env.enclClass).map(vd -> vd.sym.name);
1230                         List<Name> initParamNames = tree.sym.params.map(p -> p.name);
1231                         if (!initParamNames.equals(recordComponentNames)) {
1232                             log.error(tree, Errors.InvalidCanonicalConstructorInRecord(
1233                                     Fragments.Canonical, env.enclClass.sym.name, Fragments.CanonicalWithNameMismatch));
1234                         }
1235                         if (tree.sym.type.asMethodType().thrown != null && !tree.sym.type.asMethodType().thrown.isEmpty()) {
1236                             log.error(tree,
1237                                     Errors.InvalidCanonicalConstructorInRecord(
1238                                             TreeInfo.isCompactConstructor(tree) ? Fragments.Compact : Fragments.Canonical,
1239                                             env.enclClass.sym.name,
1240                                             Fragments.ThrowsClauseNotAllowedForCanonicalConstructor(
1241                                                     TreeInfo.isCompactConstructor(tree) ? Fragments.Compact : Fragments.Canonical)));
1242                         }
1243                     }
1244                 }
1245 
1246                 // Attribute all type annotations in the body
1247                 annotate.queueScanTreeAndTypeAnnotate(tree.body, localEnv, m, null);
1248                 annotate.flush();
1249 
1250                 // Start of constructor prologue
1251                 localEnv.info.ctorPrologue = isConstructor;
1252 
1253                 // Attribute method body.
1254                 attribStat(tree.body, localEnv);
1255             }
1256 
1257             localEnv.info.scope.leave();
1258             result = tree.type = m.type;
1259         } finally {
1260             chk.setLint(prevLint);
1261             chk.setMethod(prevMethod);
1262             env.info.ctorPrologue = ctorProloguePrev;
1263         }
1264     }
1265 
1266     public void visitVarDef(JCVariableDecl tree) {
1267         // Local variables have not been entered yet, so we need to do it now:
1268         if (env.info.scope.owner.kind == MTH || env.info.scope.owner.kind == VAR) {
1269             if (tree.sym != null) {
1270                 // parameters have already been entered
1271                 env.info.scope.enter(tree.sym);
1272             } else {
1273                 if (tree.isImplicitlyTyped() && (tree.getModifiers().flags & PARAMETER) == 0) {
1274                     if (tree.init == null) {
1275                         //cannot use 'var' without initializer
1276                         log.error(tree, Errors.CantInferLocalVarType(tree.name, Fragments.LocalMissingInit));
1277                         tree.vartype = make.Erroneous();
1278                     } else {
1279                         Fragment msg = canInferLocalVarType(tree);
1280                         if (msg != null) {
1281                             //cannot use 'var' with initializer which require an explicit target
1282                             //(e.g. lambda, method reference, array initializer).
1283                             log.error(tree, Errors.CantInferLocalVarType(tree.name, msg));
1284                             tree.vartype = make.Erroneous();
1285                         }
1286                     }
1287                 }
1288                 try {
1289                     annotate.blockAnnotations();
1290                     memberEnter.memberEnter(tree, env);
1291                 } finally {
1292                     annotate.unblockAnnotations();
1293                 }
1294             }
1295         } else {
1296             if (tree.init != null) {
1297                 // Field initializer expression need to be entered.
1298                 annotate.queueScanTreeAndTypeAnnotate(tree.init, env, tree.sym, tree.pos());
1299                 annotate.flush();
1300             }
1301         }
1302 
1303         VarSymbol v = tree.sym;
1304         Lint lint = env.info.lint.augment(v);
1305         Lint prevLint = chk.setLint(lint);
1306 
1307         // Check that the variable's declared type is well-formed.
1308         boolean isImplicitLambdaParameter = env.tree.hasTag(LAMBDA) &&
1309                 ((JCLambda)env.tree).paramKind == JCLambda.ParameterKind.IMPLICIT &&
1310                 (tree.sym.flags() & PARAMETER) != 0;
1311         chk.validate(tree.vartype, env, !isImplicitLambdaParameter && !tree.isImplicitlyTyped());
1312 
1313         try {
1314             v.getConstValue(); // ensure compile-time constant initializer is evaluated
1315             deferredLintHandler.flush(tree.pos(), lint);
1316             chk.checkDeprecatedAnnotation(tree.pos(), v);
1317 
1318             if (tree.init != null) {
1319                 if ((v.flags_field & FINAL) == 0 ||
1320                     !memberEnter.needsLazyConstValue(tree.init)) {
1321                     // Not a compile-time constant
1322                     // Attribute initializer in a new environment
1323                     // with the declared variable as owner.
1324                     // Check that initializer conforms to variable's declared type.
1325                     Env<AttrContext> initEnv = memberEnter.initEnv(tree, env);
1326                     initEnv.info.lint = lint;
1327                     // In order to catch self-references, we set the variable's
1328                     // declaration position to maximal possible value, effectively
1329                     // marking the variable as undefined.
1330                     initEnv.info.enclVar = v;
1331                     boolean previousCtorPrologue = initEnv.info.ctorPrologue;
1332                     try {
1333                         if (v.owner.kind == TYP && v.owner.isValueClass() && !v.isStatic()) {
1334                             // strict instance initializer in a value class
1335                             initEnv.info.ctorPrologue = true;
1336                         }
1337                         attribExpr(tree.init, initEnv, v.type);
1338                         if (tree.isImplicitlyTyped()) {
1339                             //fixup local variable type
1340                             v.type = chk.checkLocalVarType(tree, tree.init.type, tree.name);
1341                         }
1342                     } finally {
1343                         initEnv.info.ctorPrologue = previousCtorPrologue;
1344                     }
1345                 }
1346                 if (tree.isImplicitlyTyped()) {
1347                     setSyntheticVariableType(tree, v.type);
1348                 }
1349             }
1350             result = tree.type = v.type;
1351             if (env.enclClass.sym.isRecord() && tree.sym.owner.kind == TYP && !v.isStatic()) {
1352                 if (isNonArgsMethodInObject(v.name)) {
1353                     log.error(tree, Errors.IllegalRecordComponentName(v));
1354                 }
1355             }
1356         }
1357         finally {
1358             chk.setLint(prevLint);
1359         }
1360     }
1361 
1362     private boolean isNonArgsMethodInObject(Name name) {
1363         for (Symbol s : syms.objectType.tsym.members().getSymbolsByName(name, s -> s.kind == MTH)) {
1364             if (s.type.getParameterTypes().isEmpty()) {
1365                 return true;
1366             }
1367         }
1368         return false;
1369     }
1370 
1371     Fragment canInferLocalVarType(JCVariableDecl tree) {
1372         LocalInitScanner lis = new LocalInitScanner();
1373         lis.scan(tree.init);
1374         return lis.badInferenceMsg;
1375     }
1376 
1377     static class LocalInitScanner extends TreeScanner {
1378         Fragment badInferenceMsg = null;
1379         boolean needsTarget = true;
1380 
1381         @Override
1382         public void visitNewArray(JCNewArray tree) {
1383             if (tree.elemtype == null && needsTarget) {
1384                 badInferenceMsg = Fragments.LocalArrayMissingTarget;
1385             }
1386         }
1387 
1388         @Override
1389         public void visitLambda(JCLambda tree) {
1390             if (needsTarget) {
1391                 badInferenceMsg = Fragments.LocalLambdaMissingTarget;
1392             }
1393         }
1394 
1395         @Override
1396         public void visitTypeCast(JCTypeCast tree) {
1397             boolean prevNeedsTarget = needsTarget;
1398             try {
1399                 needsTarget = false;
1400                 super.visitTypeCast(tree);
1401             } finally {
1402                 needsTarget = prevNeedsTarget;
1403             }
1404         }
1405 
1406         @Override
1407         public void visitReference(JCMemberReference tree) {
1408             if (needsTarget) {
1409                 badInferenceMsg = Fragments.LocalMrefMissingTarget;
1410             }
1411         }
1412 
1413         @Override
1414         public void visitNewClass(JCNewClass tree) {
1415             boolean prevNeedsTarget = needsTarget;
1416             try {
1417                 needsTarget = false;
1418                 super.visitNewClass(tree);
1419             } finally {
1420                 needsTarget = prevNeedsTarget;
1421             }
1422         }
1423 
1424         @Override
1425         public void visitApply(JCMethodInvocation tree) {
1426             boolean prevNeedsTarget = needsTarget;
1427             try {
1428                 needsTarget = false;
1429                 super.visitApply(tree);
1430             } finally {
1431                 needsTarget = prevNeedsTarget;
1432             }
1433         }
1434     }
1435 
1436     public void visitSkip(JCSkip tree) {
1437         result = null;
1438     }
1439 
1440     public void visitBlock(JCBlock tree) {
1441         if (env.info.scope.owner.kind == TYP || env.info.scope.owner.kind == ERR) {
1442             // Block is a static or instance initializer;
1443             // let the owner of the environment be a freshly
1444             // created BLOCK-method.
1445             Symbol fakeOwner =
1446                 new MethodSymbol(tree.flags | BLOCK |
1447                     env.info.scope.owner.flags() & STRICTFP, names.empty, null,
1448                     env.info.scope.owner);
1449             final Env<AttrContext> localEnv =
1450                 env.dup(tree, env.info.dup(env.info.scope.dupUnshared(fakeOwner)));
1451 
1452             if ((tree.flags & STATIC) != 0) {
1453                 localEnv.info.staticLevel++;
1454             } else {
1455                 localEnv.info.instanceInitializerBlock = true;
1456             }
1457             // Attribute all type annotations in the block
1458             annotate.queueScanTreeAndTypeAnnotate(tree, localEnv, localEnv.info.scope.owner, null);
1459             annotate.flush();
1460             attribStats(tree.stats, localEnv);
1461 
1462             {
1463                 // Store init and clinit type annotations with the ClassSymbol
1464                 // to allow output in Gen.normalizeDefs.
1465                 ClassSymbol cs = (ClassSymbol)env.info.scope.owner;
1466                 List<Attribute.TypeCompound> tas = localEnv.info.scope.owner.getRawTypeAttributes();
1467                 if ((tree.flags & STATIC) != 0) {
1468                     cs.appendClassInitTypeAttributes(tas);
1469                 } else {
1470                     cs.appendInitTypeAttributes(tas);
1471                 }
1472             }
1473         } else {
1474             // Create a new local environment with a local scope.
1475             Env<AttrContext> localEnv =
1476                 env.dup(tree, env.info.dup(env.info.scope.dup()));
1477             try {
1478                 attribStats(tree.stats, localEnv);
1479             } finally {
1480                 localEnv.info.scope.leave();
1481             }
1482         }
1483         result = null;
1484     }
1485 
1486     public void visitDoLoop(JCDoWhileLoop tree) {
1487         attribStat(tree.body, env.dup(tree));
1488         attribExpr(tree.cond, env, syms.booleanType);
1489         handleLoopConditionBindings(matchBindings, tree, tree.body);
1490         result = null;
1491     }
1492 
1493     public void visitWhileLoop(JCWhileLoop tree) {
1494         attribExpr(tree.cond, env, syms.booleanType);
1495         MatchBindings condBindings = matchBindings;
1496         // include condition's bindings when true in the body:
1497         Env<AttrContext> whileEnv = bindingEnv(env, condBindings.bindingsWhenTrue);
1498         try {
1499             attribStat(tree.body, whileEnv.dup(tree));
1500         } finally {
1501             whileEnv.info.scope.leave();
1502         }
1503         handleLoopConditionBindings(condBindings, tree, tree.body);
1504         result = null;
1505     }
1506 
1507     public void visitForLoop(JCForLoop tree) {
1508         Env<AttrContext> loopEnv =
1509             env.dup(env.tree, env.info.dup(env.info.scope.dup()));
1510         MatchBindings condBindings = MatchBindingsComputer.EMPTY;
1511         try {
1512             attribStats(tree.init, loopEnv);
1513             if (tree.cond != null) {
1514                 attribExpr(tree.cond, loopEnv, syms.booleanType);
1515                 // include condition's bindings when true in the body and step:
1516                 condBindings = matchBindings;
1517             }
1518             Env<AttrContext> bodyEnv = bindingEnv(loopEnv, condBindings.bindingsWhenTrue);
1519             try {
1520                 bodyEnv.tree = tree; // before, we were not in loop!
1521                 attribStats(tree.step, bodyEnv);
1522                 attribStat(tree.body, bodyEnv);
1523             } finally {
1524                 bodyEnv.info.scope.leave();
1525             }
1526             result = null;
1527         }
1528         finally {
1529             loopEnv.info.scope.leave();
1530         }
1531         handleLoopConditionBindings(condBindings, tree, tree.body);
1532     }
1533 
1534     /**
1535      * Include condition's bindings when false after the loop, if cannot get out of the loop
1536      */
1537     private void handleLoopConditionBindings(MatchBindings condBindings,
1538                                              JCStatement loop,
1539                                              JCStatement loopBody) {
1540         if (condBindings.bindingsWhenFalse.nonEmpty() &&
1541             !breaksTo(env, loop, loopBody)) {
1542             addBindings2Scope(loop, condBindings.bindingsWhenFalse);
1543         }
1544     }
1545 
1546     private boolean breaksTo(Env<AttrContext> env, JCTree loop, JCTree body) {
1547         preFlow(body);
1548         return flow.breaksToTree(env, loop, body, make);
1549     }
1550 
1551     /**
1552      * Add given bindings to the current scope, unless there's a break to
1553      * an immediately enclosing labeled statement.
1554      */
1555     private void addBindings2Scope(JCStatement introducingStatement,
1556                                    List<BindingSymbol> bindings) {
1557         if (bindings.isEmpty()) {
1558             return ;
1559         }
1560 
1561         var searchEnv = env;
1562         while (searchEnv.tree instanceof JCLabeledStatement labeled &&
1563                labeled.body == introducingStatement) {
1564             if (breaksTo(env, labeled, labeled.body)) {
1565                 //breaking to an immediately enclosing labeled statement
1566                 return ;
1567             }
1568             searchEnv = searchEnv.next;
1569             introducingStatement = labeled;
1570         }
1571 
1572         //include condition's body when false after the while, if cannot get out of the loop
1573         bindings.forEach(env.info.scope::enter);
1574         bindings.forEach(BindingSymbol::preserveBinding);
1575     }
1576 
1577     public void visitForeachLoop(JCEnhancedForLoop tree) {
1578         Env<AttrContext> loopEnv =
1579             env.dup(env.tree, env.info.dup(env.info.scope.dup()));
1580         try {
1581             //the Formal Parameter of a for-each loop is not in the scope when
1582             //attributing the for-each expression; we mimic this by attributing
1583             //the for-each expression first (against original scope).
1584             Type exprType = types.cvarUpperBound(attribExpr(tree.expr, loopEnv));
1585             chk.checkNonVoid(tree.pos(), exprType);
1586             Type elemtype = types.elemtype(exprType); // perhaps expr is an array?
1587             if (elemtype == null) {
1588                 // or perhaps expr implements Iterable<T>?
1589                 Type base = types.asSuper(exprType, syms.iterableType.tsym);
1590                 if (base == null) {
1591                     log.error(tree.expr.pos(),
1592                               Errors.ForeachNotApplicableToType(exprType,
1593                                                                 Fragments.TypeReqArrayOrIterable));
1594                     elemtype = types.createErrorType(exprType);
1595                 } else {
1596                     List<Type> iterableParams = base.allparams();
1597                     elemtype = iterableParams.isEmpty()
1598                         ? syms.objectType
1599                         : types.wildUpperBound(iterableParams.head);
1600 
1601                     // Check the return type of the method iterator().
1602                     // This is the bare minimum we need to verify to make sure code generation doesn't crash.
1603                     Symbol iterSymbol = rs.resolveInternalMethod(tree.pos(),
1604                             loopEnv, types.skipTypeVars(exprType, false), names.iterator, List.nil(), List.nil());
1605                     if (types.asSuper(iterSymbol.type.getReturnType(), syms.iteratorType.tsym) == null) {
1606                         log.error(tree.pos(),
1607                                 Errors.ForeachNotApplicableToType(exprType, Fragments.TypeReqArrayOrIterable));
1608                     }
1609                 }
1610             }
1611             if (tree.var.isImplicitlyTyped()) {
1612                 Type inferredType = chk.checkLocalVarType(tree.var, elemtype, tree.var.name);
1613                 setSyntheticVariableType(tree.var, inferredType);
1614             }
1615             attribStat(tree.var, loopEnv);
1616             chk.checkType(tree.expr.pos(), elemtype, tree.var.sym.type);
1617             loopEnv.tree = tree; // before, we were not in loop!
1618             attribStat(tree.body, loopEnv);
1619             result = null;
1620         }
1621         finally {
1622             loopEnv.info.scope.leave();
1623         }
1624     }
1625 
1626     public void visitLabelled(JCLabeledStatement tree) {
1627         // Check that label is not used in an enclosing statement
1628         Env<AttrContext> env1 = env;
1629         while (env1 != null && !env1.tree.hasTag(CLASSDEF)) {
1630             if (env1.tree.hasTag(LABELLED) &&
1631                 ((JCLabeledStatement) env1.tree).label == tree.label) {
1632                 log.error(tree.pos(),
1633                           Errors.LabelAlreadyInUse(tree.label));
1634                 break;
1635             }
1636             env1 = env1.next;
1637         }
1638 
1639         attribStat(tree.body, env.dup(tree));
1640         result = null;
1641     }
1642 
1643     public void visitSwitch(JCSwitch tree) {
1644         handleSwitch(tree, tree.selector, tree.cases, (c, caseEnv) -> {
1645             attribStats(c.stats, caseEnv);
1646         });
1647         result = null;
1648     }
1649 
1650     public void visitSwitchExpression(JCSwitchExpression tree) {
1651         boolean wrongContext = false;
1652 
1653         tree.polyKind = (pt().hasTag(NONE) && pt() != Type.recoveryType && pt() != Infer.anyPoly) ?
1654                 PolyKind.STANDALONE : PolyKind.POLY;
1655 
1656         if (tree.polyKind == PolyKind.POLY && resultInfo.pt.hasTag(VOID)) {
1657             //this means we are returning a poly conditional from void-compatible lambda expression
1658             resultInfo.checkContext.report(tree, diags.fragment(Fragments.SwitchExpressionTargetCantBeVoid));
1659             resultInfo = recoveryInfo;
1660             wrongContext = true;
1661         }
1662 
1663         ResultInfo condInfo = tree.polyKind == PolyKind.STANDALONE ?
1664                 unknownExprInfo :
1665                 resultInfo.dup(switchExpressionContext(resultInfo.checkContext));
1666 
1667         ListBuffer<DiagnosticPosition> caseTypePositions = new ListBuffer<>();
1668         ListBuffer<Type> caseTypes = new ListBuffer<>();
1669 
1670         handleSwitch(tree, tree.selector, tree.cases, (c, caseEnv) -> {
1671             caseEnv.info.yieldResult = condInfo;
1672             attribStats(c.stats, caseEnv);
1673             new TreeScanner() {
1674                 @Override
1675                 public void visitYield(JCYield brk) {
1676                     if (brk.target == tree) {
1677                         caseTypePositions.append(brk.value != null ? brk.value.pos() : brk.pos());
1678                         caseTypes.append(brk.value != null ? brk.value.type : syms.errType);
1679                     }
1680                     super.visitYield(brk);
1681                 }
1682 
1683                 @Override public void visitClassDef(JCClassDecl tree) {}
1684                 @Override public void visitLambda(JCLambda tree) {}
1685             }.scan(c.stats);
1686         });
1687 
1688         if (tree.cases.isEmpty()) {
1689             log.error(tree.pos(),
1690                       Errors.SwitchExpressionEmpty);
1691         } else if (caseTypes.isEmpty()) {
1692             log.error(tree.pos(),
1693                       Errors.SwitchExpressionNoResultExpressions);
1694         }
1695 
1696         Type owntype = (tree.polyKind == PolyKind.STANDALONE) ? condType(caseTypePositions.toList(), caseTypes.toList()) : pt();
1697 
1698         result = tree.type = wrongContext? types.createErrorType(pt()) : check(tree, owntype, KindSelector.VAL, resultInfo);
1699     }
1700     //where:
1701         CheckContext switchExpressionContext(CheckContext checkContext) {
1702             return new Check.NestedCheckContext(checkContext) {
1703                 //this will use enclosing check context to check compatibility of
1704                 //subexpression against target type; if we are in a method check context,
1705                 //depending on whether boxing is allowed, we could have incompatibilities
1706                 @Override
1707                 public void report(DiagnosticPosition pos, JCDiagnostic details) {
1708                     enclosingContext.report(pos, diags.fragment(Fragments.IncompatibleTypeInSwitchExpression(details)));
1709                 }
1710             };
1711         }
1712 
1713     private void handleSwitch(JCTree switchTree,
1714                               JCExpression selector,
1715                               List<JCCase> cases,
1716                               BiConsumer<JCCase, Env<AttrContext>> attribCase) {
1717         Type seltype = attribExpr(selector, env);
1718 
1719         Env<AttrContext> switchEnv =
1720             env.dup(switchTree, env.info.dup(env.info.scope.dup()));
1721 
1722         try {
1723             boolean enumSwitch = (seltype.tsym.flags() & Flags.ENUM) != 0;
1724             boolean stringSwitch = types.isSameType(seltype, syms.stringType);
1725             boolean booleanSwitch = types.isSameType(types.unboxedTypeOrType(seltype), syms.booleanType);
1726             boolean errorEnumSwitch = TreeInfo.isErrorEnumSwitch(selector, cases);
1727             boolean intSwitch = types.isAssignable(seltype, syms.intType);
1728             boolean patternSwitch;
1729             if (seltype.isPrimitive() && !intSwitch) {
1730                 preview.checkSourceLevel(selector.pos(), Feature.PRIMITIVE_PATTERNS);
1731                 patternSwitch = true;
1732             }
1733             if (!enumSwitch && !stringSwitch && !errorEnumSwitch &&
1734                 !intSwitch) {
1735                 preview.checkSourceLevel(selector.pos(), Feature.PATTERN_SWITCH);
1736                 patternSwitch = true;
1737             } else {
1738                 patternSwitch = cases.stream()
1739                                      .flatMap(c -> c.labels.stream())
1740                                      .anyMatch(l -> l.hasTag(PATTERNCASELABEL) ||
1741                                                     TreeInfo.isNullCaseLabel(l));
1742             }
1743 
1744             // Attribute all cases and
1745             // check that there are no duplicate case labels or default clauses.
1746             Set<Object> constants = new HashSet<>(); // The set of case constants.
1747             boolean hasDefault = false;           // Is there a default label?
1748             boolean hasUnconditionalPattern = false; // Is there a unconditional pattern?
1749             boolean lastPatternErroneous = false; // Has the last pattern erroneous type?
1750             boolean hasNullPattern = false;       // Is there a null pattern?
1751             CaseTree.CaseKind caseKind = null;
1752             boolean wasError = false;
1753             JCCaseLabel unconditionalCaseLabel = null;
1754             for (List<JCCase> l = cases; l.nonEmpty(); l = l.tail) {
1755                 JCCase c = l.head;
1756                 if (caseKind == null) {
1757                     caseKind = c.caseKind;
1758                 } else if (caseKind != c.caseKind && !wasError) {
1759                     log.error(c.pos(),
1760                               Errors.SwitchMixingCaseTypes);
1761                     wasError = true;
1762                 }
1763                 MatchBindings currentBindings = null;
1764                 MatchBindings guardBindings = null;
1765                 for (List<JCCaseLabel> labels = c.labels; labels.nonEmpty(); labels = labels.tail) {
1766                     JCCaseLabel label = labels.head;
1767                     if (label instanceof JCConstantCaseLabel constLabel) {
1768                         JCExpression expr = constLabel.expr;
1769                         if (TreeInfo.isNull(expr)) {
1770                             preview.checkSourceLevel(expr.pos(), Feature.CASE_NULL);
1771                             if (hasNullPattern) {
1772                                 log.error(label.pos(), Errors.DuplicateCaseLabel);
1773                             }
1774                             hasNullPattern = true;
1775                             attribExpr(expr, switchEnv, seltype);
1776                             matchBindings = new MatchBindings(matchBindings.bindingsWhenTrue, matchBindings.bindingsWhenFalse, true);
1777                         } else if (enumSwitch) {
1778                             Symbol sym = enumConstant(expr, seltype);
1779                             if (sym == null) {
1780                                 if (allowPatternSwitch) {
1781                                     attribTree(expr, switchEnv, caseLabelResultInfo(seltype));
1782                                     Symbol enumSym = TreeInfo.symbol(expr);
1783                                     if (enumSym == null || !enumSym.isEnum() || enumSym.kind != VAR) {
1784                                         log.error(expr.pos(), Errors.EnumLabelMustBeEnumConstant);
1785                                     } else if (!constants.add(enumSym)) {
1786                                         log.error(label.pos(), Errors.DuplicateCaseLabel);
1787                                     }
1788                                 } else {
1789                                     log.error(expr.pos(), Errors.EnumLabelMustBeUnqualifiedEnum);
1790                                 }
1791                             } else if (!constants.add(sym)) {
1792                                 log.error(label.pos(), Errors.DuplicateCaseLabel);
1793                             }
1794                         } else if (errorEnumSwitch) {
1795                             //error recovery: the selector is erroneous, and all the case labels
1796                             //are identifiers. This could be an enum switch - don't report resolve
1797                             //error for the case label:
1798                             var prevResolveHelper = rs.basicLogResolveHelper;
1799                             try {
1800                                 rs.basicLogResolveHelper = rs.silentLogResolveHelper;
1801                                 attribExpr(expr, switchEnv, seltype);
1802                             } finally {
1803                                 rs.basicLogResolveHelper = prevResolveHelper;
1804                             }
1805                         } else {
1806                             Type pattype = attribTree(expr, switchEnv, caseLabelResultInfo(seltype));
1807                             if (!pattype.hasTag(ERROR)) {
1808                                 if (pattype.constValue() == null) {
1809                                     Symbol s = TreeInfo.symbol(expr);
1810                                     if (s != null && s.kind == TYP) {
1811                                         log.error(expr.pos(),
1812                                                   Errors.PatternExpected);
1813                                     } else if (s == null || !s.isEnum()) {
1814                                         log.error(expr.pos(),
1815                                                   (stringSwitch ? Errors.StringConstReq
1816                                                                 : intSwitch ? Errors.ConstExprReq
1817                                                                             : Errors.PatternOrEnumReq));
1818                                     } else if (!constants.add(s)) {
1819                                         log.error(label.pos(), Errors.DuplicateCaseLabel);
1820                                     }
1821                                 }
1822                                 else {
1823                                     if (!stringSwitch && !intSwitch &&
1824                                             !((pattype.getTag().isInSuperClassesOf(LONG) || pattype.getTag().equals(BOOLEAN)) &&
1825                                               types.isSameType(types.unboxedTypeOrType(seltype), pattype))) {
1826                                         log.error(label.pos(), Errors.ConstantLabelNotCompatible(pattype, seltype));
1827                                     } else if (!constants.add(pattype.constValue())) {
1828                                         log.error(c.pos(), Errors.DuplicateCaseLabel);
1829                                     }
1830                                 }
1831                             }
1832                         }
1833                     } else if (label instanceof JCDefaultCaseLabel def) {
1834                         if (hasDefault) {
1835                             log.error(label.pos(), Errors.DuplicateDefaultLabel);
1836                         } else if (hasUnconditionalPattern) {
1837                             log.error(label.pos(), Errors.UnconditionalPatternAndDefault);
1838                         }  else if (booleanSwitch && constants.containsAll(Set.of(0, 1))) {
1839                             log.error(label.pos(), Errors.DefaultAndBothBooleanValues);
1840                         }
1841                         hasDefault = true;
1842                         matchBindings = MatchBindingsComputer.EMPTY;
1843                     } else if (label instanceof JCPatternCaseLabel patternlabel) {
1844                         //pattern
1845                         JCPattern pat = patternlabel.pat;
1846                         attribExpr(pat, switchEnv, seltype);
1847                         Type primaryType = TreeInfo.primaryPatternType(pat);
1848 
1849                         if (primaryType.isPrimitive()) {
1850                             preview.checkSourceLevel(pat.pos(), Feature.PRIMITIVE_PATTERNS);
1851                         } else if (!primaryType.hasTag(TYPEVAR)) {
1852                             primaryType = chk.checkClassOrArrayType(pat.pos(), primaryType);
1853                         }
1854                         checkCastablePattern(pat.pos(), seltype, primaryType);
1855                         Type patternType = types.erasure(primaryType);
1856                         JCExpression guard = c.guard;
1857                         if (guardBindings == null && guard != null) {
1858                             MatchBindings afterPattern = matchBindings;
1859                             Env<AttrContext> bodyEnv = bindingEnv(switchEnv, matchBindings.bindingsWhenTrue);
1860                             try {
1861                                 attribExpr(guard, bodyEnv, syms.booleanType);
1862                             } finally {
1863                                 bodyEnv.info.scope.leave();
1864                             }
1865 
1866                             guardBindings = matchBindings;
1867                             matchBindings = afterPattern;
1868 
1869                             if (TreeInfo.isBooleanWithValue(guard, 0)) {
1870                                 log.error(guard.pos(), Errors.GuardHasConstantExpressionFalse);
1871                             }
1872                         }
1873                         boolean unguarded = TreeInfo.unguardedCase(c) && !pat.hasTag(RECORDPATTERN);
1874                         boolean unconditional =
1875                                 unguarded &&
1876                                 !patternType.isErroneous() &&
1877                                 types.isUnconditionallyExact(seltype, patternType);
1878                         if (unconditional) {
1879                             if (hasUnconditionalPattern) {
1880                                 log.error(pat.pos(), Errors.DuplicateUnconditionalPattern);
1881                             } else if (hasDefault) {
1882                                 log.error(pat.pos(), Errors.UnconditionalPatternAndDefault);
1883                             } else if (booleanSwitch && constants.containsAll(Set.of(0, 1))) {
1884                                 log.error(pat.pos(), Errors.UnconditionalPatternAndBothBooleanValues);
1885                             }
1886                             hasUnconditionalPattern = true;
1887                             unconditionalCaseLabel = label;
1888                         }
1889                         lastPatternErroneous = patternType.isErroneous();
1890                     } else {
1891                         Assert.error();
1892                     }
1893                     currentBindings = matchBindingsComputer.switchCase(label, currentBindings, matchBindings);
1894                 }
1895 
1896                 if (guardBindings != null) {
1897                     currentBindings = matchBindingsComputer.caseGuard(c, currentBindings, guardBindings);
1898                 }
1899 
1900                 Env<AttrContext> caseEnv =
1901                         bindingEnv(switchEnv, c, currentBindings.bindingsWhenTrue);
1902                 try {
1903                     attribCase.accept(c, caseEnv);
1904                 } finally {
1905                     caseEnv.info.scope.leave();
1906                 }
1907                 addVars(c.stats, switchEnv.info.scope);
1908 
1909                 preFlow(c);
1910                 c.completesNormally = flow.aliveAfter(caseEnv, c, make);
1911             }
1912             if (patternSwitch) {
1913                 chk.checkSwitchCaseStructure(cases);
1914                 chk.checkSwitchCaseLabelDominated(unconditionalCaseLabel, cases);
1915             }
1916             if (switchTree.hasTag(SWITCH)) {
1917                 ((JCSwitch) switchTree).hasUnconditionalPattern =
1918                         hasDefault || hasUnconditionalPattern || lastPatternErroneous;
1919                 ((JCSwitch) switchTree).patternSwitch = patternSwitch;
1920             } else if (switchTree.hasTag(SWITCH_EXPRESSION)) {
1921                 ((JCSwitchExpression) switchTree).hasUnconditionalPattern =
1922                         hasDefault || hasUnconditionalPattern || lastPatternErroneous;
1923                 ((JCSwitchExpression) switchTree).patternSwitch = patternSwitch;
1924             } else {
1925                 Assert.error(switchTree.getTag().name());
1926             }
1927         } finally {
1928             switchEnv.info.scope.leave();
1929         }
1930     }
1931     // where
1932         private ResultInfo caseLabelResultInfo(Type seltype) {
1933             return new ResultInfo(KindSelector.VAL_TYP,
1934                                   !seltype.hasTag(ERROR) ? seltype
1935                                                          : Type.noType);
1936         }
1937         /** Add any variables defined in stats to the switch scope. */
1938         private static void addVars(List<JCStatement> stats, WriteableScope switchScope) {
1939             for (;stats.nonEmpty(); stats = stats.tail) {
1940                 JCTree stat = stats.head;
1941                 if (stat.hasTag(VARDEF))
1942                     switchScope.enter(((JCVariableDecl) stat).sym);
1943             }
1944         }
1945     // where
1946     /** Return the selected enumeration constant symbol, or null. */
1947     private Symbol enumConstant(JCTree tree, Type enumType) {
1948         if (tree.hasTag(IDENT)) {
1949             JCIdent ident = (JCIdent)tree;
1950             Name name = ident.name;
1951             for (Symbol sym : enumType.tsym.members().getSymbolsByName(name)) {
1952                 if (sym.kind == VAR) {
1953                     Symbol s = ident.sym = sym;
1954                     ((VarSymbol)s).getConstValue(); // ensure initializer is evaluated
1955                     ident.type = s.type;
1956                     return ((s.flags_field & Flags.ENUM) == 0)
1957                         ? null : s;
1958                 }
1959             }
1960         }
1961         return null;
1962     }
1963 
1964     public void visitSynchronized(JCSynchronized tree) {
1965         boolean identityType = chk.checkIdentityType(tree.pos(), attribExpr(tree.lock, env));
1966         if (env.info.lint.isEnabled(LintCategory.SYNCHRONIZATION) &&
1967                 identityType &&
1968                 isValueBased(tree.lock.type)) {
1969             log.warning(LintCategory.SYNCHRONIZATION, tree.pos(), Warnings.AttemptToSynchronizeOnInstanceOfValueBasedClass);
1970         }
1971         attribStat(tree.body, env);
1972         result = null;
1973     }
1974         // where
1975         private boolean isValueBased(Type t) {
1976             return t != null && t.tsym != null && (t.tsym.flags() & VALUE_BASED) != 0;
1977         }
1978 
1979     public void visitTry(JCTry tree) {
1980         // Create a new local environment with a local
1981         Env<AttrContext> localEnv = env.dup(tree, env.info.dup(env.info.scope.dup()));
1982         try {
1983             boolean isTryWithResource = tree.resources.nonEmpty();
1984             // Create a nested environment for attributing the try block if needed
1985             Env<AttrContext> tryEnv = isTryWithResource ?
1986                 env.dup(tree, localEnv.info.dup(localEnv.info.scope.dup())) :
1987                 localEnv;
1988             try {
1989                 // Attribute resource declarations
1990                 for (JCTree resource : tree.resources) {
1991                     CheckContext twrContext = new Check.NestedCheckContext(resultInfo.checkContext) {
1992                         @Override
1993                         public void report(DiagnosticPosition pos, JCDiagnostic details) {
1994                             chk.basicHandler.report(pos, diags.fragment(Fragments.TryNotApplicableToType(details)));
1995                         }
1996                     };
1997                     ResultInfo twrResult =
1998                         new ResultInfo(KindSelector.VAR,
1999                                        syms.autoCloseableType,
2000                                        twrContext);
2001                     if (resource.hasTag(VARDEF)) {
2002                         attribStat(resource, tryEnv);
2003                         twrResult.check(resource, resource.type);
2004 
2005                         //check that resource type cannot throw InterruptedException
2006                         checkAutoCloseable(resource.pos(), localEnv, resource.type);
2007 
2008                         VarSymbol var = ((JCVariableDecl) resource).sym;
2009 
2010                         var.flags_field |= Flags.FINAL;
2011                         var.setData(ElementKind.RESOURCE_VARIABLE);
2012                     } else {
2013                         attribTree(resource, tryEnv, twrResult);
2014                     }
2015                 }
2016                 // Attribute body
2017                 attribStat(tree.body, tryEnv);
2018             } finally {
2019                 if (isTryWithResource)
2020                     tryEnv.info.scope.leave();
2021             }
2022 
2023             // Attribute catch clauses
2024             for (List<JCCatch> l = tree.catchers; l.nonEmpty(); l = l.tail) {
2025                 JCCatch c = l.head;
2026                 Env<AttrContext> catchEnv =
2027                     localEnv.dup(c, localEnv.info.dup(localEnv.info.scope.dup()));
2028                 try {
2029                     Type ctype = attribStat(c.param, catchEnv);
2030                     if (TreeInfo.isMultiCatch(c)) {
2031                         //multi-catch parameter is implicitly marked as final
2032                         c.param.sym.flags_field |= FINAL | UNION;
2033                     }
2034                     if (c.param.sym.kind == VAR) {
2035                         c.param.sym.setData(ElementKind.EXCEPTION_PARAMETER);
2036                     }
2037                     chk.checkType(c.param.vartype.pos(),
2038                                   chk.checkClassType(c.param.vartype.pos(), ctype),
2039                                   syms.throwableType);
2040                     attribStat(c.body, catchEnv);
2041                 } finally {
2042                     catchEnv.info.scope.leave();
2043                 }
2044             }
2045 
2046             // Attribute finalizer
2047             if (tree.finalizer != null) attribStat(tree.finalizer, localEnv);
2048             result = null;
2049         }
2050         finally {
2051             localEnv.info.scope.leave();
2052         }
2053     }
2054 
2055     void checkAutoCloseable(DiagnosticPosition pos, Env<AttrContext> env, Type resource) {
2056         if (!resource.isErroneous() &&
2057             types.asSuper(resource, syms.autoCloseableType.tsym) != null &&
2058             !types.isSameType(resource, syms.autoCloseableType)) { // Don't emit warning for AutoCloseable itself
2059             Symbol close = syms.noSymbol;
2060             Log.DiagnosticHandler discardHandler = new Log.DiscardDiagnosticHandler(log);
2061             try {
2062                 close = rs.resolveQualifiedMethod(pos,
2063                         env,
2064                         types.skipTypeVars(resource, false),
2065                         names.close,
2066                         List.nil(),
2067                         List.nil());
2068             }
2069             finally {
2070                 log.popDiagnosticHandler(discardHandler);
2071             }
2072             if (close.kind == MTH &&
2073                     close.overrides(syms.autoCloseableClose, resource.tsym, types, true) &&
2074                     chk.isHandled(syms.interruptedExceptionType, types.memberType(resource, close).getThrownTypes()) &&
2075                     env.info.lint.isEnabled(LintCategory.TRY)) {
2076                 log.warning(LintCategory.TRY, pos, Warnings.TryResourceThrowsInterruptedExc(resource));
2077             }
2078         }
2079     }
2080 
2081     public void visitConditional(JCConditional tree) {
2082         Type condtype = attribExpr(tree.cond, env, syms.booleanType);
2083         MatchBindings condBindings = matchBindings;
2084 
2085         tree.polyKind = (pt().hasTag(NONE) && pt() != Type.recoveryType && pt() != Infer.anyPoly ||
2086                 isBooleanOrNumeric(env, tree)) ?
2087                 PolyKind.STANDALONE : PolyKind.POLY;
2088 
2089         if (tree.polyKind == PolyKind.POLY && resultInfo.pt.hasTag(VOID)) {
2090             //this means we are returning a poly conditional from void-compatible lambda expression
2091             resultInfo.checkContext.report(tree, diags.fragment(Fragments.ConditionalTargetCantBeVoid));
2092             result = tree.type = types.createErrorType(resultInfo.pt);
2093             return;
2094         }
2095 
2096         ResultInfo condInfo = tree.polyKind == PolyKind.STANDALONE ?
2097                 unknownExprInfo :
2098                 resultInfo.dup(conditionalContext(resultInfo.checkContext));
2099 
2100 
2101         // x ? y : z
2102         // include x's bindings when true in y
2103         // include x's bindings when false in z
2104 
2105         Type truetype;
2106         Env<AttrContext> trueEnv = bindingEnv(env, condBindings.bindingsWhenTrue);
2107         try {
2108             truetype = attribTree(tree.truepart, trueEnv, condInfo);
2109         } finally {
2110             trueEnv.info.scope.leave();
2111         }
2112 
2113         MatchBindings trueBindings = matchBindings;
2114 
2115         Type falsetype;
2116         Env<AttrContext> falseEnv = bindingEnv(env, condBindings.bindingsWhenFalse);
2117         try {
2118             falsetype = attribTree(tree.falsepart, falseEnv, condInfo);
2119         } finally {
2120             falseEnv.info.scope.leave();
2121         }
2122 
2123         MatchBindings falseBindings = matchBindings;
2124 
2125         Type owntype = (tree.polyKind == PolyKind.STANDALONE) ?
2126                 condType(List.of(tree.truepart.pos(), tree.falsepart.pos()),
2127                          List.of(truetype, falsetype)) : pt();
2128         if (condtype.constValue() != null &&
2129                 truetype.constValue() != null &&
2130                 falsetype.constValue() != null &&
2131                 !owntype.hasTag(NONE)) {
2132             //constant folding
2133             owntype = cfolder.coerce(condtype.isTrue() ? truetype : falsetype, owntype);
2134         }
2135         result = check(tree, owntype, KindSelector.VAL, resultInfo);
2136         matchBindings = matchBindingsComputer.conditional(tree, condBindings, trueBindings, falseBindings);
2137     }
2138     //where
2139         private boolean isBooleanOrNumeric(Env<AttrContext> env, JCExpression tree) {
2140             switch (tree.getTag()) {
2141                 case LITERAL: return ((JCLiteral)tree).typetag.isSubRangeOf(DOUBLE) ||
2142                               ((JCLiteral)tree).typetag == BOOLEAN ||
2143                               ((JCLiteral)tree).typetag == BOT;
2144                 case LAMBDA: case REFERENCE: return false;
2145                 case PARENS: return isBooleanOrNumeric(env, ((JCParens)tree).expr);
2146                 case CONDEXPR:
2147                     JCConditional condTree = (JCConditional)tree;
2148                     return isBooleanOrNumeric(env, condTree.truepart) &&
2149                             isBooleanOrNumeric(env, condTree.falsepart);
2150                 case APPLY:
2151                     JCMethodInvocation speculativeMethodTree =
2152                             (JCMethodInvocation)deferredAttr.attribSpeculative(
2153                                     tree, env, unknownExprInfo,
2154                                     argumentAttr.withLocalCacheContext());
2155                     Symbol msym = TreeInfo.symbol(speculativeMethodTree.meth);
2156                     Type receiverType = speculativeMethodTree.meth.hasTag(IDENT) ?
2157                             env.enclClass.type :
2158                             ((JCFieldAccess)speculativeMethodTree.meth).selected.type;
2159                     Type owntype = types.memberType(receiverType, msym).getReturnType();
2160                     return primitiveOrBoxed(owntype);
2161                 case NEWCLASS:
2162                     JCExpression className =
2163                             removeClassParams.translate(((JCNewClass)tree).clazz);
2164                     JCExpression speculativeNewClassTree =
2165                             (JCExpression)deferredAttr.attribSpeculative(
2166                                     className, env, unknownTypeInfo,
2167                                     argumentAttr.withLocalCacheContext());
2168                     return primitiveOrBoxed(speculativeNewClassTree.type);
2169                 default:
2170                     Type speculativeType = deferredAttr.attribSpeculative(tree, env, unknownExprInfo,
2171                             argumentAttr.withLocalCacheContext()).type;
2172                     return primitiveOrBoxed(speculativeType);
2173             }
2174         }
2175         //where
2176             boolean primitiveOrBoxed(Type t) {
2177                 return (!t.hasTag(TYPEVAR) && !t.isErroneous() && types.unboxedTypeOrType(t).isPrimitive());
2178             }
2179 
2180             TreeTranslator removeClassParams = new TreeTranslator() {
2181                 @Override
2182                 public void visitTypeApply(JCTypeApply tree) {
2183                     result = translate(tree.clazz);
2184                 }
2185             };
2186 
2187         CheckContext conditionalContext(CheckContext checkContext) {
2188             return new Check.NestedCheckContext(checkContext) {
2189                 //this will use enclosing check context to check compatibility of
2190                 //subexpression against target type; if we are in a method check context,
2191                 //depending on whether boxing is allowed, we could have incompatibilities
2192                 @Override
2193                 public void report(DiagnosticPosition pos, JCDiagnostic details) {
2194                     enclosingContext.report(pos, diags.fragment(Fragments.IncompatibleTypeInConditional(details)));
2195                 }
2196             };
2197         }
2198 
2199         /** Compute the type of a conditional expression, after
2200          *  checking that it exists.  See JLS 15.25. Does not take into
2201          *  account the special case where condition and both arms
2202          *  are constants.
2203          *
2204          *  @param pos      The source position to be used for error
2205          *                  diagnostics.
2206          *  @param thentype The type of the expression's then-part.
2207          *  @param elsetype The type of the expression's else-part.
2208          */
2209         Type condType(List<DiagnosticPosition> positions, List<Type> condTypes) {
2210             if (condTypes.isEmpty()) {
2211                 return syms.objectType; //TODO: how to handle?
2212             }
2213             Type first = condTypes.head;
2214             // If same type, that is the result
2215             if (condTypes.tail.stream().allMatch(t -> types.isSameType(first, t)))
2216                 return first.baseType();
2217 
2218             List<Type> unboxedTypes = condTypes.stream()
2219                                                .map(t -> t.isPrimitive() ? t : types.unboxedType(t))
2220                                                .collect(List.collector());
2221 
2222             // Otherwise, if both arms can be converted to a numeric
2223             // type, return the least numeric type that fits both arms
2224             // (i.e. return larger of the two, or return int if one
2225             // arm is short, the other is char).
2226             if (unboxedTypes.stream().allMatch(t -> t.isPrimitive())) {
2227                 // If one arm has an integer subrange type (i.e., byte,
2228                 // short, or char), and the other is an integer constant
2229                 // that fits into the subrange, return the subrange type.
2230                 for (Type type : unboxedTypes) {
2231                     if (!type.getTag().isStrictSubRangeOf(INT)) {
2232                         continue;
2233                     }
2234                     if (unboxedTypes.stream().filter(t -> t != type).allMatch(t -> t.hasTag(INT) && types.isAssignable(t, type)))
2235                         return type.baseType();
2236                 }
2237 
2238                 for (TypeTag tag : primitiveTags) {
2239                     Type candidate = syms.typeOfTag[tag.ordinal()];
2240                     if (unboxedTypes.stream().allMatch(t -> types.isSubtype(t, candidate))) {
2241                         return candidate;
2242                     }
2243                 }
2244             }
2245 
2246             // Those were all the cases that could result in a primitive
2247             condTypes = condTypes.stream()
2248                                  .map(t -> t.isPrimitive() ? types.boxedClass(t).type : t)
2249                                  .collect(List.collector());
2250 
2251             for (Type type : condTypes) {
2252                 if (condTypes.stream().filter(t -> t != type).allMatch(t -> types.isAssignable(t, type)))
2253                     return type.baseType();
2254             }
2255 
2256             Iterator<DiagnosticPosition> posIt = positions.iterator();
2257 
2258             condTypes = condTypes.stream()
2259                                  .map(t -> chk.checkNonVoid(posIt.next(), t))
2260                                  .collect(List.collector());
2261 
2262             // both are known to be reference types.  The result is
2263             // lub(thentype,elsetype). This cannot fail, as it will
2264             // always be possible to infer "Object" if nothing better.
2265             return types.lub(condTypes.stream()
2266                         .map(t -> t.baseType())
2267                         .filter(t -> !t.hasTag(BOT))
2268                         .collect(List.collector()));
2269         }
2270 
2271     static final TypeTag[] primitiveTags = new TypeTag[]{
2272         BYTE,
2273         CHAR,
2274         SHORT,
2275         INT,
2276         LONG,
2277         FLOAT,
2278         DOUBLE,
2279         BOOLEAN,
2280     };
2281 
2282     Env<AttrContext> bindingEnv(Env<AttrContext> env, List<BindingSymbol> bindings) {
2283         return bindingEnv(env, env.tree, bindings);
2284     }
2285 
2286     Env<AttrContext> bindingEnv(Env<AttrContext> env, JCTree newTree, List<BindingSymbol> bindings) {
2287         Env<AttrContext> env1 = env.dup(newTree, env.info.dup(env.info.scope.dup()));
2288         bindings.forEach(env1.info.scope::enter);
2289         return env1;
2290     }
2291 
2292     public void visitIf(JCIf tree) {
2293         attribExpr(tree.cond, env, syms.booleanType);
2294 
2295         // if (x) { y } [ else z ]
2296         // include x's bindings when true in y
2297         // include x's bindings when false in z
2298 
2299         MatchBindings condBindings = matchBindings;
2300         Env<AttrContext> thenEnv = bindingEnv(env, condBindings.bindingsWhenTrue);
2301 
2302         try {
2303             attribStat(tree.thenpart, thenEnv);
2304         } finally {
2305             thenEnv.info.scope.leave();
2306         }
2307 
2308         preFlow(tree.thenpart);
2309         boolean aliveAfterThen = flow.aliveAfter(env, tree.thenpart, make);
2310         boolean aliveAfterElse;
2311 
2312         if (tree.elsepart != null) {
2313             Env<AttrContext> elseEnv = bindingEnv(env, condBindings.bindingsWhenFalse);
2314             try {
2315                 attribStat(tree.elsepart, elseEnv);
2316             } finally {
2317                 elseEnv.info.scope.leave();
2318             }
2319             preFlow(tree.elsepart);
2320             aliveAfterElse = flow.aliveAfter(env, tree.elsepart, make);
2321         } else {
2322             aliveAfterElse = true;
2323         }
2324 
2325         chk.checkEmptyIf(tree);
2326 
2327         List<BindingSymbol> afterIfBindings = List.nil();
2328 
2329         if (aliveAfterThen && !aliveAfterElse) {
2330             afterIfBindings = condBindings.bindingsWhenTrue;
2331         } else if (aliveAfterElse && !aliveAfterThen) {
2332             afterIfBindings = condBindings.bindingsWhenFalse;
2333         }
2334 
2335         addBindings2Scope(tree, afterIfBindings);
2336 
2337         result = null;
2338     }
2339 
2340         void preFlow(JCTree tree) {
2341             attrRecover.doRecovery();
2342             new PostAttrAnalyzer() {
2343                 @Override
2344                 public void scan(JCTree tree) {
2345                     if (tree == null ||
2346                             (tree.type != null &&
2347                             tree.type == Type.stuckType)) {
2348                         //don't touch stuck expressions!
2349                         return;
2350                     }
2351                     super.scan(tree);
2352                 }
2353 
2354                 @Override
2355                 public void visitClassDef(JCClassDecl that) {
2356                     if (that.sym != null) {
2357                         // Method preFlow shouldn't visit class definitions
2358                         // that have not been entered and attributed.
2359                         // See JDK-8254557 and JDK-8203277 for more details.
2360                         super.visitClassDef(that);
2361                     }
2362                 }
2363 
2364                 @Override
2365                 public void visitLambda(JCLambda that) {
2366                     if (that.type != null) {
2367                         // Method preFlow shouldn't visit lambda expressions
2368                         // that have not been entered and attributed.
2369                         // See JDK-8254557 and JDK-8203277 for more details.
2370                         super.visitLambda(that);
2371                     }
2372                 }
2373             }.scan(tree);
2374         }
2375 
2376     public void visitExec(JCExpressionStatement tree) {
2377         //a fresh environment is required for 292 inference to work properly ---
2378         //see Infer.instantiatePolymorphicSignatureInstance()
2379         Env<AttrContext> localEnv = env.dup(tree);
2380         attribExpr(tree.expr, localEnv);
2381         result = null;
2382     }
2383 
2384     public void visitBreak(JCBreak tree) {
2385         tree.target = findJumpTarget(tree.pos(), tree.getTag(), tree.label, env);
2386         result = null;
2387     }
2388 
2389     public void visitYield(JCYield tree) {
2390         if (env.info.yieldResult != null) {
2391             attribTree(tree.value, env, env.info.yieldResult);
2392             tree.target = findJumpTarget(tree.pos(), tree.getTag(), names.empty, env);
2393         } else {
2394             log.error(tree.pos(), tree.value.hasTag(PARENS)
2395                     ? Errors.NoSwitchExpressionQualify
2396                     : Errors.NoSwitchExpression);
2397             attribTree(tree.value, env, unknownExprInfo);
2398         }
2399         result = null;
2400     }
2401 
2402     public void visitContinue(JCContinue tree) {
2403         tree.target = findJumpTarget(tree.pos(), tree.getTag(), tree.label, env);
2404         result = null;
2405     }
2406     //where
2407         /** Return the target of a break, continue or yield statement,
2408          *  if it exists, report an error if not.
2409          *  Note: The target of a labelled break or continue is the
2410          *  (non-labelled) statement tree referred to by the label,
2411          *  not the tree representing the labelled statement itself.
2412          *
2413          *  @param pos     The position to be used for error diagnostics
2414          *  @param tag     The tag of the jump statement. This is either
2415          *                 Tree.BREAK or Tree.CONTINUE.
2416          *  @param label   The label of the jump statement, or null if no
2417          *                 label is given.
2418          *  @param env     The environment current at the jump statement.
2419          */
2420         private JCTree findJumpTarget(DiagnosticPosition pos,
2421                                                    JCTree.Tag tag,
2422                                                    Name label,
2423                                                    Env<AttrContext> env) {
2424             Pair<JCTree, Error> jumpTarget = findJumpTargetNoError(tag, label, env);
2425 
2426             if (jumpTarget.snd != null) {
2427                 log.error(pos, jumpTarget.snd);
2428             }
2429 
2430             return jumpTarget.fst;
2431         }
2432         /** Return the target of a break or continue statement, if it exists,
2433          *  report an error if not.
2434          *  Note: The target of a labelled break or continue is the
2435          *  (non-labelled) statement tree referred to by the label,
2436          *  not the tree representing the labelled statement itself.
2437          *
2438          *  @param tag     The tag of the jump statement. This is either
2439          *                 Tree.BREAK or Tree.CONTINUE.
2440          *  @param label   The label of the jump statement, or null if no
2441          *                 label is given.
2442          *  @param env     The environment current at the jump statement.
2443          */
2444         private Pair<JCTree, JCDiagnostic.Error> findJumpTargetNoError(JCTree.Tag tag,
2445                                                                        Name label,
2446                                                                        Env<AttrContext> env) {
2447             // Search environments outwards from the point of jump.
2448             Env<AttrContext> env1 = env;
2449             JCDiagnostic.Error pendingError = null;
2450             LOOP:
2451             while (env1 != null) {
2452                 switch (env1.tree.getTag()) {
2453                     case LABELLED:
2454                         JCLabeledStatement labelled = (JCLabeledStatement)env1.tree;
2455                         if (label == labelled.label) {
2456                             // If jump is a continue, check that target is a loop.
2457                             if (tag == CONTINUE) {
2458                                 if (!labelled.body.hasTag(DOLOOP) &&
2459                                         !labelled.body.hasTag(WHILELOOP) &&
2460                                         !labelled.body.hasTag(FORLOOP) &&
2461                                         !labelled.body.hasTag(FOREACHLOOP)) {
2462                                     pendingError = Errors.NotLoopLabel(label);
2463                                 }
2464                                 // Found labelled statement target, now go inwards
2465                                 // to next non-labelled tree.
2466                                 return Pair.of(TreeInfo.referencedStatement(labelled), pendingError);
2467                             } else {
2468                                 return Pair.of(labelled, pendingError);
2469                             }
2470                         }
2471                         break;
2472                     case DOLOOP:
2473                     case WHILELOOP:
2474                     case FORLOOP:
2475                     case FOREACHLOOP:
2476                         if (label == null) return Pair.of(env1.tree, pendingError);
2477                         break;
2478                     case SWITCH:
2479                         if (label == null && tag == BREAK) return Pair.of(env1.tree, null);
2480                         break;
2481                     case SWITCH_EXPRESSION:
2482                         if (tag == YIELD) {
2483                             return Pair.of(env1.tree, null);
2484                         } else if (tag == BREAK) {
2485                             pendingError = Errors.BreakOutsideSwitchExpression;
2486                         } else {
2487                             pendingError = Errors.ContinueOutsideSwitchExpression;
2488                         }
2489                         break;
2490                     case LAMBDA:
2491                     case METHODDEF:
2492                     case CLASSDEF:
2493                         break LOOP;
2494                     default:
2495                 }
2496                 env1 = env1.next;
2497             }
2498             if (label != null)
2499                 return Pair.of(null, Errors.UndefLabel(label));
2500             else if (pendingError != null)
2501                 return Pair.of(null, pendingError);
2502             else if (tag == CONTINUE)
2503                 return Pair.of(null, Errors.ContOutsideLoop);
2504             else
2505                 return Pair.of(null, Errors.BreakOutsideSwitchLoop);
2506         }
2507 
2508     public void visitReturn(JCReturn tree) {
2509         // Check that there is an enclosing method which is
2510         // nested within than the enclosing class.
2511         if (env.info.returnResult == null) {
2512             log.error(tree.pos(), Errors.RetOutsideMeth);
2513         } else if (env.info.yieldResult != null) {
2514             log.error(tree.pos(), Errors.ReturnOutsideSwitchExpression);
2515             if (tree.expr != null) {
2516                 attribExpr(tree.expr, env, env.info.yieldResult.pt);
2517             }
2518         } else if (!env.info.isLambda &&
2519                 !env.info.isNewClass &&
2520                 env.enclMethod != null &&
2521                 TreeInfo.isCompactConstructor(env.enclMethod)) {
2522             log.error(env.enclMethod,
2523                     Errors.InvalidCanonicalConstructorInRecord(Fragments.Compact, env.enclMethod.sym.name, Fragments.CanonicalCantHaveReturnStatement));
2524         } else {
2525             // Attribute return expression, if it exists, and check that
2526             // it conforms to result type of enclosing method.
2527             if (tree.expr != null) {
2528                 if (env.info.returnResult.pt.hasTag(VOID)) {
2529                     env.info.returnResult.checkContext.report(tree.expr.pos(),
2530                               diags.fragment(Fragments.UnexpectedRetVal));
2531                 }
2532                 attribTree(tree.expr, env, env.info.returnResult);
2533             } else if (!env.info.returnResult.pt.hasTag(VOID) &&
2534                     !env.info.returnResult.pt.hasTag(NONE)) {
2535                 env.info.returnResult.checkContext.report(tree.pos(),
2536                               diags.fragment(Fragments.MissingRetVal(env.info.returnResult.pt)));
2537             }
2538         }
2539         result = null;
2540     }
2541 
2542     public void visitThrow(JCThrow tree) {
2543         Type owntype = attribExpr(tree.expr, env, Type.noType);
2544         chk.checkType(tree, owntype, syms.throwableType);
2545         result = null;
2546     }
2547 
2548     public void visitAssert(JCAssert tree) {
2549         attribExpr(tree.cond, env, syms.booleanType);
2550         if (tree.detail != null) {
2551             chk.checkNonVoid(tree.detail.pos(), attribExpr(tree.detail, env));
2552         }
2553         result = null;
2554     }
2555 
2556      /** Visitor method for method invocations.
2557      *  NOTE: The method part of an application will have in its type field
2558      *        the return type of the method, not the method's type itself!
2559      */
2560     public void visitApply(JCMethodInvocation tree) {
2561         // The local environment of a method application is
2562         // a new environment nested in the current one.
2563         Env<AttrContext> localEnv = env.dup(tree, env.info.dup());
2564 
2565         // The types of the actual method arguments.
2566         List<Type> argtypes;
2567 
2568         // The types of the actual method type arguments.
2569         List<Type> typeargtypes = null;
2570 
2571         Name methName = TreeInfo.name(tree.meth);
2572 
2573         boolean isConstructorCall =
2574             methName == names._this || methName == names._super;
2575 
2576         ListBuffer<Type> argtypesBuf = new ListBuffer<>();
2577         if (isConstructorCall) {
2578 
2579             // Attribute arguments, yielding list of argument types.
2580             KindSelector kind = attribArgs(KindSelector.MTH, tree.args, localEnv, argtypesBuf);
2581             argtypes = argtypesBuf.toList();
2582             typeargtypes = attribTypes(tree.typeargs, localEnv);
2583 
2584             // Done with this()/super() parameters. End of constructor prologue.
2585             env.info.ctorPrologue = false;
2586 
2587             // Variable `site' points to the class in which the called
2588             // constructor is defined.
2589             Type site = env.enclClass.sym.type;
2590             if (methName == names._super) {
2591                 if (site == syms.objectType) {
2592                     log.error(tree.meth.pos(), Errors.NoSuperclass(site));
2593                     site = types.createErrorType(syms.objectType);
2594                 } else {
2595                     site = types.supertype(site);
2596                 }
2597             }
2598 
2599             if (site.hasTag(CLASS)) {
2600                 Type encl = site.getEnclosingType();
2601                 while (encl != null && encl.hasTag(TYPEVAR))
2602                     encl = encl.getUpperBound();
2603                 if (encl.hasTag(CLASS)) {
2604                     // we are calling a nested class
2605 
2606                     if (tree.meth.hasTag(SELECT)) {
2607                         JCTree qualifier = ((JCFieldAccess) tree.meth).selected;
2608 
2609                         // We are seeing a prefixed call, of the form
2610                         //     <expr>.super(...).
2611                         // Check that the prefix expression conforms
2612                         // to the outer instance type of the class.
2613                         chk.checkRefType(qualifier.pos(),
2614                                          attribExpr(qualifier, localEnv,
2615                                                     encl));
2616                     } else if (methName == names._super) {
2617                         // qualifier omitted; check for existence
2618                         // of an appropriate implicit qualifier.
2619                         rs.resolveImplicitThis(tree.meth.pos(),
2620                                                localEnv, site, true);
2621                     }
2622                 } else if (tree.meth.hasTag(SELECT)) {
2623                     log.error(tree.meth.pos(),
2624                               Errors.IllegalQualNotIcls(site.tsym));
2625                     attribExpr(((JCFieldAccess) tree.meth).selected, localEnv, site);
2626                 }
2627 
2628                 // if we're calling a java.lang.Enum constructor,
2629                 // prefix the implicit String and int parameters
2630                 if (site.tsym == syms.enumSym)
2631                     argtypes = argtypes.prepend(syms.intType).prepend(syms.stringType);
2632 
2633                 // Resolve the called constructor under the assumption
2634                 // that we are referring to a superclass instance of the
2635                 // current instance (JLS ???).
2636                 boolean selectSuperPrev = localEnv.info.selectSuper;
2637                 localEnv.info.selectSuper = true;
2638                 localEnv.info.pendingResolutionPhase = null;
2639                 Symbol sym = rs.resolveConstructor(
2640                     tree.meth.pos(), localEnv, site, argtypes, typeargtypes);
2641                 localEnv.info.selectSuper = selectSuperPrev;
2642 
2643                 // Set method symbol to resolved constructor...
2644                 TreeInfo.setSymbol(tree.meth, sym);
2645 
2646                 // ...and check that it is legal in the current context.
2647                 // (this will also set the tree's type)
2648                 Type mpt = newMethodTemplate(resultInfo.pt, argtypes, typeargtypes);
2649                 checkId(tree.meth, site, sym, localEnv,
2650                         new ResultInfo(kind, mpt));
2651             } else if (site.hasTag(ERROR) && tree.meth.hasTag(SELECT)) {
2652                 attribExpr(((JCFieldAccess) tree.meth).selected, localEnv, site);
2653             }
2654             // Otherwise, `site' is an error type and we do nothing
2655             result = tree.type = syms.voidType;
2656         } else {
2657             // Otherwise, we are seeing a regular method call.
2658             // Attribute the arguments, yielding list of argument types, ...
2659             KindSelector kind = attribArgs(KindSelector.VAL, tree.args, localEnv, argtypesBuf);
2660             argtypes = argtypesBuf.toList();
2661             typeargtypes = attribAnyTypes(tree.typeargs, localEnv);
2662 
2663             // ... and attribute the method using as a prototype a methodtype
2664             // whose formal argument types is exactly the list of actual
2665             // arguments (this will also set the method symbol).
2666             Type mpt = newMethodTemplate(resultInfo.pt, argtypes, typeargtypes);
2667             localEnv.info.pendingResolutionPhase = null;
2668             Type mtype = attribTree(tree.meth, localEnv, new ResultInfo(kind, mpt, resultInfo.checkContext));
2669 
2670             // Compute the result type.
2671             Type restype = mtype.getReturnType();
2672             if (restype.hasTag(WILDCARD))
2673                 throw new AssertionError(mtype);
2674 
2675             Type qualifier = (tree.meth.hasTag(SELECT))
2676                     ? ((JCFieldAccess) tree.meth).selected.type
2677                     : env.enclClass.sym.type;
2678             Symbol msym = TreeInfo.symbol(tree.meth);
2679             restype = adjustMethodReturnType(msym, qualifier, methName, argtypes, restype);
2680 
2681             chk.checkRefTypes(tree.typeargs, typeargtypes);
2682 
2683             // Check that value of resulting type is admissible in the
2684             // current context.  Also, capture the return type
2685             Type capturedRes = resultInfo.checkContext.inferenceContext().cachedCapture(tree, restype, true);
2686             result = check(tree, capturedRes, KindSelector.VAL, resultInfo);
2687         }
2688         chk.validate(tree.typeargs, localEnv);
2689     }
2690     //where
2691         Type adjustMethodReturnType(Symbol msym, Type qualifierType, Name methodName, List<Type> argtypes, Type restype) {
2692             if (msym != null &&
2693                     (msym.owner == syms.objectType.tsym || msym.owner.isInterface()) &&
2694                     methodName == names.getClass &&
2695                     argtypes.isEmpty()) {
2696                 // as a special case, x.getClass() has type Class<? extends |X|>
2697                 return new ClassType(restype.getEnclosingType(),
2698                         List.of(new WildcardType(types.erasure(qualifierType.baseType()),
2699                                 BoundKind.EXTENDS,
2700                                 syms.boundClass)),
2701                         restype.tsym,
2702                         restype.getMetadata());
2703             } else if (msym != null &&
2704                     msym.owner == syms.arrayClass &&
2705                     methodName == names.clone &&
2706                     types.isArray(qualifierType)) {
2707                 // as a special case, array.clone() has a result that is
2708                 // the same as static type of the array being cloned
2709                 return qualifierType;
2710             } else {
2711                 return restype;
2712             }
2713         }
2714 
2715         /** Obtain a method type with given argument types.
2716          */
2717         Type newMethodTemplate(Type restype, List<Type> argtypes, List<Type> typeargtypes) {
2718             MethodType mt = new MethodType(argtypes, restype, List.nil(), syms.methodClass);
2719             return (typeargtypes == null) ? mt : (Type)new ForAll(typeargtypes, mt);
2720         }
2721 
2722     public void visitNewClass(final JCNewClass tree) {
2723         Type owntype = types.createErrorType(tree.type);
2724 
2725         // The local environment of a class creation is
2726         // a new environment nested in the current one.
2727         Env<AttrContext> localEnv = env.dup(tree, env.info.dup());
2728 
2729         // The anonymous inner class definition of the new expression,
2730         // if one is defined by it.
2731         JCClassDecl cdef = tree.def;
2732 
2733         // If enclosing class is given, attribute it, and
2734         // complete class name to be fully qualified
2735         JCExpression clazz = tree.clazz; // Class field following new
2736         JCExpression clazzid;            // Identifier in class field
2737         JCAnnotatedType annoclazzid;     // Annotated type enclosing clazzid
2738         annoclazzid = null;
2739 
2740         if (clazz.hasTag(TYPEAPPLY)) {
2741             clazzid = ((JCTypeApply) clazz).clazz;
2742             if (clazzid.hasTag(ANNOTATED_TYPE)) {
2743                 annoclazzid = (JCAnnotatedType) clazzid;
2744                 clazzid = annoclazzid.underlyingType;
2745             }
2746         } else {
2747             if (clazz.hasTag(ANNOTATED_TYPE)) {
2748                 annoclazzid = (JCAnnotatedType) clazz;
2749                 clazzid = annoclazzid.underlyingType;
2750             } else {
2751                 clazzid = clazz;
2752             }
2753         }
2754 
2755         JCExpression clazzid1 = clazzid; // The same in fully qualified form
2756 
2757         if (tree.encl != null) {
2758             // We are seeing a qualified new, of the form
2759             //    <expr>.new C <...> (...) ...
2760             // In this case, we let clazz stand for the name of the
2761             // allocated class C prefixed with the type of the qualifier
2762             // expression, so that we can
2763             // resolve it with standard techniques later. I.e., if
2764             // <expr> has type T, then <expr>.new C <...> (...)
2765             // yields a clazz T.C.
2766             Type encltype = chk.checkRefType(tree.encl.pos(),
2767                                              attribExpr(tree.encl, env));
2768             // TODO 308: in <expr>.new C, do we also want to add the type annotations
2769             // from expr to the combined type, or not? Yes, do this.
2770             clazzid1 = make.at(clazz.pos).Select(make.Type(encltype),
2771                                                  ((JCIdent) clazzid).name);
2772 
2773             EndPosTable endPosTable = this.env.toplevel.endPositions;
2774             endPosTable.storeEnd(clazzid1, clazzid.getEndPosition(endPosTable));
2775             if (clazz.hasTag(ANNOTATED_TYPE)) {
2776                 JCAnnotatedType annoType = (JCAnnotatedType) clazz;
2777                 List<JCAnnotation> annos = annoType.annotations;
2778 
2779                 if (annoType.underlyingType.hasTag(TYPEAPPLY)) {
2780                     clazzid1 = make.at(tree.pos).
2781                         TypeApply(clazzid1,
2782                                   ((JCTypeApply) clazz).arguments);
2783                 }
2784 
2785                 clazzid1 = make.at(tree.pos).
2786                     AnnotatedType(annos, clazzid1);
2787             } else if (clazz.hasTag(TYPEAPPLY)) {
2788                 clazzid1 = make.at(tree.pos).
2789                     TypeApply(clazzid1,
2790                               ((JCTypeApply) clazz).arguments);
2791             }
2792 
2793             clazz = clazzid1;
2794         }
2795 
2796         // Attribute clazz expression and store
2797         // symbol + type back into the attributed tree.
2798         Type clazztype;
2799 
2800         try {
2801             env.info.isNewClass = true;
2802             clazztype = TreeInfo.isEnumInit(env.tree) ?
2803                 attribIdentAsEnumType(env, (JCIdent)clazz) :
2804                 attribType(clazz, env);
2805         } finally {
2806             env.info.isNewClass = false;
2807         }
2808 
2809         clazztype = chk.checkDiamond(tree, clazztype);
2810         chk.validate(clazz, localEnv);
2811         if (tree.encl != null) {
2812             // We have to work in this case to store
2813             // symbol + type back into the attributed tree.
2814             tree.clazz.type = clazztype;
2815             TreeInfo.setSymbol(clazzid, TreeInfo.symbol(clazzid1));
2816             clazzid.type = ((JCIdent) clazzid).sym.type;
2817             if (annoclazzid != null) {
2818                 annoclazzid.type = clazzid.type;
2819             }
2820             if (!clazztype.isErroneous()) {
2821                 if (cdef != null && clazztype.tsym.isInterface()) {
2822                     log.error(tree.encl.pos(), Errors.AnonClassImplIntfNoQualForNew);
2823                 } else if (clazztype.tsym.isStatic()) {
2824                     log.error(tree.encl.pos(), Errors.QualifiedNewOfStaticClass(clazztype.tsym));
2825                 }
2826             }
2827         } else if (!clazztype.tsym.isInterface() &&
2828                    (clazztype.tsym.flags_field & NOOUTERTHIS) == 0 &&
2829                    clazztype.getEnclosingType().hasTag(CLASS)) {
2830             // Check for the existence of an apropos outer instance
2831             rs.resolveImplicitThis(tree.pos(), env, clazztype);
2832         }
2833 
2834         // Attribute constructor arguments.
2835         ListBuffer<Type> argtypesBuf = new ListBuffer<>();
2836         final KindSelector pkind =
2837             attribArgs(KindSelector.VAL, tree.args, localEnv, argtypesBuf);
2838         List<Type> argtypes = argtypesBuf.toList();
2839         List<Type> typeargtypes = attribTypes(tree.typeargs, localEnv);
2840 
2841         if (clazztype.hasTag(CLASS) || clazztype.hasTag(ERROR)) {
2842             // Enums may not be instantiated except implicitly
2843             if ((clazztype.tsym.flags_field & Flags.ENUM) != 0 &&
2844                 (!env.tree.hasTag(VARDEF) ||
2845                  (((JCVariableDecl) env.tree).mods.flags & Flags.ENUM) == 0 ||
2846                  ((JCVariableDecl) env.tree).init != tree))
2847                 log.error(tree.pos(), Errors.EnumCantBeInstantiated);
2848 
2849             boolean isSpeculativeDiamondInferenceRound = TreeInfo.isDiamond(tree) &&
2850                     resultInfo.checkContext.deferredAttrContext().mode == DeferredAttr.AttrMode.SPECULATIVE;
2851             boolean skipNonDiamondPath = false;
2852             // Check that class is not abstract
2853             if (cdef == null && !isSpeculativeDiamondInferenceRound && // class body may be nulled out in speculative tree copy
2854                 (clazztype.tsym.flags() & (ABSTRACT | INTERFACE)) != 0) {
2855                 log.error(tree.pos(),
2856                           Errors.AbstractCantBeInstantiated(clazztype.tsym));
2857                 skipNonDiamondPath = true;
2858             } else if (cdef != null && clazztype.tsym.isInterface()) {
2859                 // Check that no constructor arguments are given to
2860                 // anonymous classes implementing an interface
2861                 if (!argtypes.isEmpty())
2862                     log.error(tree.args.head.pos(), Errors.AnonClassImplIntfNoArgs);
2863 
2864                 if (!typeargtypes.isEmpty())
2865                     log.error(tree.typeargs.head.pos(), Errors.AnonClassImplIntfNoTypeargs);
2866 
2867                 // Error recovery: pretend no arguments were supplied.
2868                 argtypes = List.nil();
2869                 typeargtypes = List.nil();
2870                 skipNonDiamondPath = true;
2871             }
2872             if (TreeInfo.isDiamond(tree)) {
2873                 ClassType site = new ClassType(clazztype.getEnclosingType(),
2874                             clazztype.tsym.type.getTypeArguments(),
2875                                                clazztype.tsym,
2876                                                clazztype.getMetadata());
2877 
2878                 Env<AttrContext> diamondEnv = localEnv.dup(tree);
2879                 diamondEnv.info.selectSuper = cdef != null || tree.classDeclRemoved();
2880                 diamondEnv.info.pendingResolutionPhase = null;
2881 
2882                 //if the type of the instance creation expression is a class type
2883                 //apply method resolution inference (JLS 15.12.2.7). The return type
2884                 //of the resolved constructor will be a partially instantiated type
2885                 Symbol constructor = rs.resolveDiamond(tree.pos(),
2886                             diamondEnv,
2887                             site,
2888                             argtypes,
2889                             typeargtypes);
2890                 tree.constructor = constructor.baseSymbol();
2891 
2892                 final TypeSymbol csym = clazztype.tsym;
2893                 ResultInfo diamondResult = new ResultInfo(pkind, newMethodTemplate(resultInfo.pt, argtypes, typeargtypes),
2894                         diamondContext(tree, csym, resultInfo.checkContext), CheckMode.NO_TREE_UPDATE);
2895                 Type constructorType = tree.constructorType = types.createErrorType(clazztype);
2896                 constructorType = checkId(tree, site,
2897                         constructor,
2898                         diamondEnv,
2899                         diamondResult);
2900 
2901                 tree.clazz.type = types.createErrorType(clazztype);
2902                 if (!constructorType.isErroneous()) {
2903                     tree.clazz.type = clazz.type = constructorType.getReturnType();
2904                     tree.constructorType = types.createMethodTypeWithReturn(constructorType, syms.voidType);
2905                 }
2906                 clazztype = chk.checkClassType(tree.clazz, tree.clazz.type, true);
2907             }
2908 
2909             // Resolve the called constructor under the assumption
2910             // that we are referring to a superclass instance of the
2911             // current instance (JLS ???).
2912             else if (!skipNonDiamondPath) {
2913                 //the following code alters some of the fields in the current
2914                 //AttrContext - hence, the current context must be dup'ed in
2915                 //order to avoid downstream failures
2916                 Env<AttrContext> rsEnv = localEnv.dup(tree);
2917                 rsEnv.info.selectSuper = cdef != null;
2918                 rsEnv.info.pendingResolutionPhase = null;
2919                 tree.constructor = rs.resolveConstructor(
2920                     tree.pos(), rsEnv, clazztype, argtypes, typeargtypes);
2921                 if (cdef == null) { //do not check twice!
2922                     tree.constructorType = checkId(tree,
2923                             clazztype,
2924                             tree.constructor,
2925                             rsEnv,
2926                             new ResultInfo(pkind, newMethodTemplate(syms.voidType, argtypes, typeargtypes), CheckMode.NO_TREE_UPDATE));
2927                     if (rsEnv.info.lastResolveVarargs())
2928                         Assert.check(tree.constructorType.isErroneous() || tree.varargsElement != null);
2929                 }
2930             }
2931 
2932             if (cdef != null) {
2933                 visitAnonymousClassDefinition(tree, clazz, clazztype, cdef, localEnv, argtypes, typeargtypes, pkind);
2934                 return;
2935             }
2936 
2937             if (tree.constructor != null && tree.constructor.kind == MTH)
2938                 owntype = clazztype;
2939         }
2940         result = check(tree, owntype, KindSelector.VAL, resultInfo);
2941         InferenceContext inferenceContext = resultInfo.checkContext.inferenceContext();
2942         if (tree.constructorType != null && inferenceContext.free(tree.constructorType)) {
2943             //we need to wait for inference to finish and then replace inference vars in the constructor type
2944             inferenceContext.addFreeTypeListener(List.of(tree.constructorType),
2945                     instantiatedContext -> {
2946                         tree.constructorType = instantiatedContext.asInstType(tree.constructorType);
2947                     });
2948         }
2949         chk.validate(tree.typeargs, localEnv);
2950     }
2951 
2952         // where
2953         private void visitAnonymousClassDefinition(JCNewClass tree, JCExpression clazz, Type clazztype,
2954                                                    JCClassDecl cdef, Env<AttrContext> localEnv,
2955                                                    List<Type> argtypes, List<Type> typeargtypes,
2956                                                    KindSelector pkind) {
2957             // We are seeing an anonymous class instance creation.
2958             // In this case, the class instance creation
2959             // expression
2960             //
2961             //    E.new <typeargs1>C<typargs2>(args) { ... }
2962             //
2963             // is represented internally as
2964             //
2965             //    E . new <typeargs1>C<typargs2>(args) ( class <empty-name> { ... } )  .
2966             //
2967             // This expression is then *transformed* as follows:
2968             //
2969             // (1) add an extends or implements clause
2970             // (2) add a constructor.
2971             //
2972             // For instance, if C is a class, and ET is the type of E,
2973             // the expression
2974             //
2975             //    E.new <typeargs1>C<typargs2>(args) { ... }
2976             //
2977             // is translated to (where X is a fresh name and typarams is the
2978             // parameter list of the super constructor):
2979             //
2980             //   new <typeargs1>X(<*nullchk*>E, args) where
2981             //     X extends C<typargs2> {
2982             //       <typarams> X(ET e, args) {
2983             //         e.<typeargs1>super(args)
2984             //       }
2985             //       ...
2986             //     }
2987             InferenceContext inferenceContext = resultInfo.checkContext.inferenceContext();
2988             Type enclType = clazztype.getEnclosingType();
2989             if (enclType != null &&
2990                     enclType.hasTag(CLASS) &&
2991                     !chk.checkDenotable((ClassType)enclType)) {
2992                 log.error(tree.encl, Errors.EnclosingClassTypeNonDenotable(enclType));
2993             }
2994             final boolean isDiamond = TreeInfo.isDiamond(tree);
2995             if (isDiamond
2996                     && ((tree.constructorType != null && inferenceContext.free(tree.constructorType))
2997                     || (tree.clazz.type != null && inferenceContext.free(tree.clazz.type)))) {
2998                 final ResultInfo resultInfoForClassDefinition = this.resultInfo;
2999                 Env<AttrContext> dupLocalEnv = copyEnv(localEnv);
3000                 inferenceContext.addFreeTypeListener(List.of(tree.constructorType, tree.clazz.type),
3001                         instantiatedContext -> {
3002                             tree.constructorType = instantiatedContext.asInstType(tree.constructorType);
3003                             tree.clazz.type = clazz.type = instantiatedContext.asInstType(clazz.type);
3004                             ResultInfo prevResult = this.resultInfo;
3005                             try {
3006                                 this.resultInfo = resultInfoForClassDefinition;
3007                                 visitAnonymousClassDefinition(tree, clazz, clazz.type, cdef,
3008                                         dupLocalEnv, argtypes, typeargtypes, pkind);
3009                             } finally {
3010                                 this.resultInfo = prevResult;
3011                             }
3012                         });
3013             } else {
3014                 if (isDiamond && clazztype.hasTag(CLASS)) {
3015                     List<Type> invalidDiamondArgs = chk.checkDiamondDenotable((ClassType)clazztype);
3016                     if (!clazztype.isErroneous() && invalidDiamondArgs.nonEmpty()) {
3017                         // One or more types inferred in the previous steps is non-denotable.
3018                         Fragment fragment = Diamond(clazztype.tsym);
3019                         log.error(tree.clazz.pos(),
3020                                 Errors.CantApplyDiamond1(
3021                                         fragment,
3022                                         invalidDiamondArgs.size() > 1 ?
3023                                                 DiamondInvalidArgs(invalidDiamondArgs, fragment) :
3024                                                 DiamondInvalidArg(invalidDiamondArgs, fragment)));
3025                     }
3026                     // For <>(){}, inferred types must also be accessible.
3027                     for (Type t : clazztype.getTypeArguments()) {
3028                         rs.checkAccessibleType(env, t);
3029                     }
3030                 }
3031 
3032                 // If we already errored, be careful to avoid a further avalanche. ErrorType answers
3033                 // false for isInterface call even when the original type is an interface.
3034                 boolean implementing = clazztype.tsym.isInterface() ||
3035                         clazztype.isErroneous() && !clazztype.getOriginalType().hasTag(NONE) &&
3036                         clazztype.getOriginalType().tsym.isInterface();
3037 
3038                 if (implementing) {
3039                     cdef.implementing = List.of(clazz);
3040                 } else {
3041                     cdef.extending = clazz;
3042                 }
3043 
3044                 if (resultInfo.checkContext.deferredAttrContext().mode == DeferredAttr.AttrMode.CHECK &&
3045                     rs.isSerializable(clazztype)) {
3046                     localEnv.info.isSerializable = true;
3047                 }
3048 
3049                 attribStat(cdef, localEnv);
3050 
3051                 List<Type> finalargtypes;
3052                 // If an outer instance is given,
3053                 // prefix it to the constructor arguments
3054                 // and delete it from the new expression
3055                 if (tree.encl != null && !clazztype.tsym.isInterface()) {
3056                     finalargtypes = argtypes.prepend(tree.encl.type);
3057                 } else {
3058                     finalargtypes = argtypes;
3059                 }
3060 
3061                 // Reassign clazztype and recompute constructor. As this necessarily involves
3062                 // another attribution pass for deferred types in the case of <>, replicate
3063                 // them. Original arguments have right decorations already.
3064                 if (isDiamond && pkind.contains(KindSelector.POLY)) {
3065                     finalargtypes = finalargtypes.map(deferredAttr.deferredCopier);
3066                 }
3067 
3068                 clazztype = clazztype.hasTag(ERROR) ? types.createErrorType(cdef.sym.type)
3069                                                     : cdef.sym.type;
3070                 Symbol sym = tree.constructor = rs.resolveConstructor(
3071                         tree.pos(), localEnv, clazztype, finalargtypes, typeargtypes);
3072                 Assert.check(!sym.kind.isResolutionError());
3073                 tree.constructor = sym;
3074                 tree.constructorType = checkId(tree,
3075                         clazztype,
3076                         tree.constructor,
3077                         localEnv,
3078                         new ResultInfo(pkind, newMethodTemplate(syms.voidType, finalargtypes, typeargtypes), CheckMode.NO_TREE_UPDATE));
3079             }
3080             Type owntype = (tree.constructor != null && tree.constructor.kind == MTH) ?
3081                                 clazztype : types.createErrorType(tree.type);
3082             result = check(tree, owntype, KindSelector.VAL, resultInfo.dup(CheckMode.NO_INFERENCE_HOOK));
3083             chk.validate(tree.typeargs, localEnv);
3084         }
3085 
3086         CheckContext diamondContext(JCNewClass clazz, TypeSymbol tsym, CheckContext checkContext) {
3087             return new Check.NestedCheckContext(checkContext) {
3088                 @Override
3089                 public void report(DiagnosticPosition _unused, JCDiagnostic details) {
3090                     enclosingContext.report(clazz.clazz,
3091                             diags.fragment(Fragments.CantApplyDiamond1(Fragments.Diamond(tsym), details)));
3092                 }
3093             };
3094         }
3095 
3096     /** Make an attributed null check tree.
3097      */
3098     public JCExpression makeNullCheck(JCExpression arg) {
3099         // optimization: new Outer() can never be null; skip null check
3100         if (arg.getTag() == NEWCLASS)
3101             return arg;
3102         // optimization: X.this is never null; skip null check
3103         Name name = TreeInfo.name(arg);
3104         if (name == names._this || name == names._super) return arg;
3105 
3106         JCTree.Tag optag = NULLCHK;
3107         JCUnary tree = make.at(arg.pos).Unary(optag, arg);
3108         tree.operator = operators.resolveUnary(arg, optag, arg.type);
3109         tree.type = arg.type;
3110         return tree;
3111     }
3112 
3113     public void visitNewArray(JCNewArray tree) {
3114         Type owntype = types.createErrorType(tree.type);
3115         Env<AttrContext> localEnv = env.dup(tree);
3116         Type elemtype;
3117         if (tree.elemtype != null) {
3118             elemtype = attribType(tree.elemtype, localEnv);
3119             chk.validate(tree.elemtype, localEnv);
3120             owntype = elemtype;
3121             for (List<JCExpression> l = tree.dims; l.nonEmpty(); l = l.tail) {
3122                 attribExpr(l.head, localEnv, syms.intType);
3123                 owntype = new ArrayType(owntype, syms.arrayClass);
3124             }
3125         } else {
3126             // we are seeing an untyped aggregate { ... }
3127             // this is allowed only if the prototype is an array
3128             if (pt().hasTag(ARRAY)) {
3129                 elemtype = types.elemtype(pt());
3130             } else {
3131                 if (!pt().hasTag(ERROR) &&
3132                         (env.info.enclVar == null || !env.info.enclVar.type.isErroneous())) {
3133                     log.error(tree.pos(),
3134                               Errors.IllegalInitializerForType(pt()));
3135                 }
3136                 elemtype = types.createErrorType(pt());
3137             }
3138         }
3139         if (tree.elems != null) {
3140             attribExprs(tree.elems, localEnv, elemtype);
3141             owntype = new ArrayType(elemtype, syms.arrayClass);
3142         }
3143         if (!types.isReifiable(elemtype))
3144             log.error(tree.pos(), Errors.GenericArrayCreation);
3145         result = check(tree, owntype, KindSelector.VAL, resultInfo);
3146     }
3147 
3148     /*
3149      * A lambda expression can only be attributed when a target-type is available.
3150      * In addition, if the target-type is that of a functional interface whose
3151      * descriptor contains inference variables in argument position the lambda expression
3152      * is 'stuck' (see DeferredAttr).
3153      */
3154     @Override
3155     public void visitLambda(final JCLambda that) {
3156         boolean wrongContext = false;
3157         if (pt().isErroneous() || (pt().hasTag(NONE) && pt() != Type.recoveryType)) {
3158             if (pt().hasTag(NONE) && (env.info.enclVar == null || !env.info.enclVar.type.isErroneous())) {
3159                 //lambda only allowed in assignment or method invocation/cast context
3160                 log.error(that.pos(), Errors.UnexpectedLambda);
3161             }
3162             resultInfo = recoveryInfo;
3163             wrongContext = true;
3164         }
3165         //create an environment for attribution of the lambda expression
3166         final Env<AttrContext> localEnv = lambdaEnv(that, env);
3167         boolean needsRecovery =
3168                 resultInfo.checkContext.deferredAttrContext().mode == DeferredAttr.AttrMode.CHECK;
3169         try {
3170             if (needsRecovery && rs.isSerializable(pt())) {
3171                 localEnv.info.isSerializable = true;
3172                 localEnv.info.isSerializableLambda = true;
3173             }
3174             List<Type> explicitParamTypes = null;
3175             if (that.paramKind == JCLambda.ParameterKind.EXPLICIT) {
3176                 //attribute lambda parameters
3177                 attribStats(that.params, localEnv);
3178                 explicitParamTypes = TreeInfo.types(that.params);
3179             }
3180 
3181             TargetInfo targetInfo = getTargetInfo(that, resultInfo, explicitParamTypes);
3182             Type currentTarget = targetInfo.target;
3183             Type lambdaType = targetInfo.descriptor;
3184 
3185             if (currentTarget.isErroneous()) {
3186                 result = that.type = currentTarget;
3187                 return;
3188             }
3189 
3190             setFunctionalInfo(localEnv, that, pt(), lambdaType, currentTarget, resultInfo.checkContext);
3191 
3192             if (lambdaType.hasTag(FORALL)) {
3193                 //lambda expression target desc cannot be a generic method
3194                 Fragment msg = Fragments.InvalidGenericLambdaTarget(lambdaType,
3195                                                                     kindName(currentTarget.tsym),
3196                                                                     currentTarget.tsym);
3197                 resultInfo.checkContext.report(that, diags.fragment(msg));
3198                 result = that.type = types.createErrorType(pt());
3199                 return;
3200             }
3201 
3202             if (that.paramKind == JCLambda.ParameterKind.IMPLICIT) {
3203                 //add param type info in the AST
3204                 List<Type> actuals = lambdaType.getParameterTypes();
3205                 List<JCVariableDecl> params = that.params;
3206 
3207                 boolean arityMismatch = false;
3208 
3209                 while (params.nonEmpty()) {
3210                     if (actuals.isEmpty()) {
3211                         //not enough actuals to perform lambda parameter inference
3212                         arityMismatch = true;
3213                     }
3214                     //reset previously set info
3215                     Type argType = arityMismatch ?
3216                             syms.errType :
3217                             actuals.head;
3218                     if (params.head.isImplicitlyTyped()) {
3219                         setSyntheticVariableType(params.head, argType);
3220                     }
3221                     params.head.sym = null;
3222                     actuals = actuals.isEmpty() ?
3223                             actuals :
3224                             actuals.tail;
3225                     params = params.tail;
3226                 }
3227 
3228                 //attribute lambda parameters
3229                 attribStats(that.params, localEnv);
3230 
3231                 if (arityMismatch) {
3232                     resultInfo.checkContext.report(that, diags.fragment(Fragments.IncompatibleArgTypesInLambda));
3233                         result = that.type = types.createErrorType(currentTarget);
3234                         return;
3235                 }
3236             }
3237 
3238             //from this point on, no recovery is needed; if we are in assignment context
3239             //we will be able to attribute the whole lambda body, regardless of errors;
3240             //if we are in a 'check' method context, and the lambda is not compatible
3241             //with the target-type, it will be recovered anyway in Attr.checkId
3242             needsRecovery = false;
3243 
3244             ResultInfo bodyResultInfo = localEnv.info.returnResult =
3245                     lambdaBodyResult(that, lambdaType, resultInfo);
3246 
3247             if (that.getBodyKind() == JCLambda.BodyKind.EXPRESSION) {
3248                 attribTree(that.getBody(), localEnv, bodyResultInfo);
3249             } else {
3250                 JCBlock body = (JCBlock)that.body;
3251                 if (body == breakTree &&
3252                         resultInfo.checkContext.deferredAttrContext().mode == AttrMode.CHECK) {
3253                     breakTreeFound(copyEnv(localEnv));
3254                 }
3255                 attribStats(body.stats, localEnv);
3256             }
3257 
3258             result = check(that, currentTarget, KindSelector.VAL, resultInfo);
3259 
3260             boolean isSpeculativeRound =
3261                     resultInfo.checkContext.deferredAttrContext().mode == DeferredAttr.AttrMode.SPECULATIVE;
3262 
3263             preFlow(that);
3264             flow.analyzeLambda(env, that, make, isSpeculativeRound);
3265 
3266             that.type = currentTarget; //avoids recovery at this stage
3267             checkLambdaCompatible(that, lambdaType, resultInfo.checkContext);
3268 
3269             if (!isSpeculativeRound) {
3270                 //add thrown types as bounds to the thrown types free variables if needed:
3271                 if (resultInfo.checkContext.inferenceContext().free(lambdaType.getThrownTypes())) {
3272                     List<Type> inferredThrownTypes = flow.analyzeLambdaThrownTypes(env, that, make);
3273                     if(!checkExConstraints(inferredThrownTypes, lambdaType.getThrownTypes(), resultInfo.checkContext.inferenceContext())) {
3274                         log.error(that, Errors.IncompatibleThrownTypesInMref(lambdaType.getThrownTypes()));
3275                     }
3276                 }
3277 
3278                 checkAccessibleTypes(that, localEnv, resultInfo.checkContext.inferenceContext(), lambdaType, currentTarget);
3279             }
3280             result = wrongContext ? that.type = types.createErrorType(pt())
3281                                   : check(that, currentTarget, KindSelector.VAL, resultInfo);
3282         } catch (Types.FunctionDescriptorLookupError ex) {
3283             JCDiagnostic cause = ex.getDiagnostic();
3284             resultInfo.checkContext.report(that, cause);
3285             result = that.type = types.createErrorType(pt());
3286             return;
3287         } catch (CompletionFailure cf) {
3288             chk.completionError(that.pos(), cf);
3289         } catch (Throwable t) {
3290             //when an unexpected exception happens, avoid attempts to attribute the same tree again
3291             //as that would likely cause the same exception again.
3292             needsRecovery = false;
3293             throw t;
3294         } finally {
3295             localEnv.info.scope.leave();
3296             if (needsRecovery) {
3297                 Type prevResult = result;
3298                 try {
3299                     attribTree(that, env, recoveryInfo);
3300                 } finally {
3301                     if (result == Type.recoveryType) {
3302                         result = prevResult;
3303                     }
3304                 }
3305             }
3306         }
3307     }
3308     //where
3309         class TargetInfo {
3310             Type target;
3311             Type descriptor;
3312 
3313             public TargetInfo(Type target, Type descriptor) {
3314                 this.target = target;
3315                 this.descriptor = descriptor;
3316             }
3317         }
3318 
3319         TargetInfo getTargetInfo(JCPolyExpression that, ResultInfo resultInfo, List<Type> explicitParamTypes) {
3320             Type lambdaType;
3321             Type currentTarget = resultInfo.pt;
3322             if (resultInfo.pt != Type.recoveryType) {
3323                 /* We need to adjust the target. If the target is an
3324                  * intersection type, for example: SAM & I1 & I2 ...
3325                  * the target will be updated to SAM
3326                  */
3327                 currentTarget = targetChecker.visit(currentTarget, that);
3328                 if (!currentTarget.isIntersection()) {
3329                     if (explicitParamTypes != null) {
3330                         currentTarget = infer.instantiateFunctionalInterface(that,
3331                                 currentTarget, explicitParamTypes, resultInfo.checkContext);
3332                     }
3333                     currentTarget = types.removeWildcards(currentTarget);
3334                     lambdaType = types.findDescriptorType(currentTarget);
3335                 } else {
3336                     IntersectionClassType ict = (IntersectionClassType)currentTarget;
3337                     ListBuffer<Type> components = new ListBuffer<>();
3338                     for (Type bound : ict.getExplicitComponents()) {
3339                         if (explicitParamTypes != null) {
3340                             try {
3341                                 bound = infer.instantiateFunctionalInterface(that,
3342                                         bound, explicitParamTypes, resultInfo.checkContext);
3343                             } catch (FunctionDescriptorLookupError t) {
3344                                 // do nothing
3345                             }
3346                         }
3347                         bound = types.removeWildcards(bound);
3348                         components.add(bound);
3349                     }
3350                     currentTarget = types.makeIntersectionType(components.toList());
3351                     currentTarget.tsym.flags_field |= INTERFACE;
3352                     lambdaType = types.findDescriptorType(currentTarget);
3353                 }
3354 
3355             } else {
3356                 currentTarget = Type.recoveryType;
3357                 lambdaType = fallbackDescriptorType(that);
3358             }
3359             if (that.hasTag(LAMBDA) && lambdaType.hasTag(FORALL)) {
3360                 //lambda expression target desc cannot be a generic method
3361                 Fragment msg = Fragments.InvalidGenericLambdaTarget(lambdaType,
3362                                                                     kindName(currentTarget.tsym),
3363                                                                     currentTarget.tsym);
3364                 resultInfo.checkContext.report(that, diags.fragment(msg));
3365                 currentTarget = types.createErrorType(pt());
3366             }
3367             return new TargetInfo(currentTarget, lambdaType);
3368         }
3369 
3370         void preFlow(JCLambda tree) {
3371             attrRecover.doRecovery();
3372             new PostAttrAnalyzer() {
3373                 @Override
3374                 public void scan(JCTree tree) {
3375                     if (tree == null ||
3376                             (tree.type != null &&
3377                             tree.type == Type.stuckType)) {
3378                         //don't touch stuck expressions!
3379                         return;
3380                     }
3381                     super.scan(tree);
3382                 }
3383 
3384                 @Override
3385                 public void visitClassDef(JCClassDecl that) {
3386                     // or class declaration trees!
3387                 }
3388 
3389                 public void visitLambda(JCLambda that) {
3390                     // or lambda expressions!
3391                 }
3392             }.scan(tree.body);
3393         }
3394 
3395         Types.MapVisitor<DiagnosticPosition> targetChecker = new Types.MapVisitor<DiagnosticPosition>() {
3396 
3397             @Override
3398             public Type visitClassType(ClassType t, DiagnosticPosition pos) {
3399                 return t.isIntersection() ?
3400                         visitIntersectionClassType((IntersectionClassType)t, pos) : t;
3401             }
3402 
3403             public Type visitIntersectionClassType(IntersectionClassType ict, DiagnosticPosition pos) {
3404                 types.findDescriptorSymbol(makeNotionalInterface(ict, pos));
3405                 return ict;
3406             }
3407 
3408             private TypeSymbol makeNotionalInterface(IntersectionClassType ict, DiagnosticPosition pos) {
3409                 ListBuffer<Type> targs = new ListBuffer<>();
3410                 ListBuffer<Type> supertypes = new ListBuffer<>();
3411                 for (Type i : ict.interfaces_field) {
3412                     if (i.isParameterized()) {
3413                         targs.appendList(i.tsym.type.allparams());
3414                     }
3415                     supertypes.append(i.tsym.type);
3416                 }
3417                 IntersectionClassType notionalIntf = types.makeIntersectionType(supertypes.toList());
3418                 notionalIntf.allparams_field = targs.toList();
3419                 notionalIntf.tsym.flags_field |= INTERFACE;
3420                 return notionalIntf.tsym;
3421             }
3422         };
3423 
3424         private Type fallbackDescriptorType(JCExpression tree) {
3425             switch (tree.getTag()) {
3426                 case LAMBDA:
3427                     JCLambda lambda = (JCLambda)tree;
3428                     List<Type> argtypes = List.nil();
3429                     for (JCVariableDecl param : lambda.params) {
3430                         argtypes = param.vartype != null && param.vartype.type != null ?
3431                                 argtypes.append(param.vartype.type) :
3432                                 argtypes.append(syms.errType);
3433                     }
3434                     return new MethodType(argtypes, Type.recoveryType,
3435                             List.of(syms.throwableType), syms.methodClass);
3436                 case REFERENCE:
3437                     return new MethodType(List.nil(), Type.recoveryType,
3438                             List.of(syms.throwableType), syms.methodClass);
3439                 default:
3440                     Assert.error("Cannot get here!");
3441             }
3442             return null;
3443         }
3444 
3445         private void checkAccessibleTypes(final DiagnosticPosition pos, final Env<AttrContext> env,
3446                 final InferenceContext inferenceContext, final Type... ts) {
3447             checkAccessibleTypes(pos, env, inferenceContext, List.from(ts));
3448         }
3449 
3450         private void checkAccessibleTypes(final DiagnosticPosition pos, final Env<AttrContext> env,
3451                 final InferenceContext inferenceContext, final List<Type> ts) {
3452             if (inferenceContext.free(ts)) {
3453                 inferenceContext.addFreeTypeListener(ts,
3454                         solvedContext -> checkAccessibleTypes(pos, env, solvedContext, solvedContext.asInstTypes(ts)));
3455             } else {
3456                 for (Type t : ts) {
3457                     rs.checkAccessibleType(env, t);
3458                 }
3459             }
3460         }
3461 
3462         /**
3463          * Lambda/method reference have a special check context that ensures
3464          * that i.e. a lambda return type is compatible with the expected
3465          * type according to both the inherited context and the assignment
3466          * context.
3467          */
3468         class FunctionalReturnContext extends Check.NestedCheckContext {
3469 
3470             FunctionalReturnContext(CheckContext enclosingContext) {
3471                 super(enclosingContext);
3472             }
3473 
3474             @Override
3475             public boolean compatible(Type found, Type req, Warner warn) {
3476                 //return type must be compatible in both current context and assignment context
3477                 return chk.basicHandler.compatible(inferenceContext().asUndetVar(found), inferenceContext().asUndetVar(req), warn);
3478             }
3479 
3480             @Override
3481             public void report(DiagnosticPosition pos, JCDiagnostic details) {
3482                 enclosingContext.report(pos, diags.fragment(Fragments.IncompatibleRetTypeInLambda(details)));
3483             }
3484         }
3485 
3486         class ExpressionLambdaReturnContext extends FunctionalReturnContext {
3487 
3488             JCExpression expr;
3489             boolean expStmtExpected;
3490 
3491             ExpressionLambdaReturnContext(JCExpression expr, CheckContext enclosingContext) {
3492                 super(enclosingContext);
3493                 this.expr = expr;
3494             }
3495 
3496             @Override
3497             public void report(DiagnosticPosition pos, JCDiagnostic details) {
3498                 if (expStmtExpected) {
3499                     enclosingContext.report(pos, diags.fragment(Fragments.StatExprExpected));
3500                 } else {
3501                     super.report(pos, details);
3502                 }
3503             }
3504 
3505             @Override
3506             public boolean compatible(Type found, Type req, Warner warn) {
3507                 //a void return is compatible with an expression statement lambda
3508                 if (req.hasTag(VOID)) {
3509                     expStmtExpected = true;
3510                     return TreeInfo.isExpressionStatement(expr);
3511                 } else {
3512                     return super.compatible(found, req, warn);
3513                 }
3514             }
3515         }
3516 
3517         ResultInfo lambdaBodyResult(JCLambda that, Type descriptor, ResultInfo resultInfo) {
3518             FunctionalReturnContext funcContext = that.getBodyKind() == JCLambda.BodyKind.EXPRESSION ?
3519                     new ExpressionLambdaReturnContext((JCExpression)that.getBody(), resultInfo.checkContext) :
3520                     new FunctionalReturnContext(resultInfo.checkContext);
3521 
3522             return descriptor.getReturnType() == Type.recoveryType ?
3523                     recoveryInfo :
3524                     new ResultInfo(KindSelector.VAL,
3525                             descriptor.getReturnType(), funcContext);
3526         }
3527 
3528         /**
3529         * Lambda compatibility. Check that given return types, thrown types, parameter types
3530         * are compatible with the expected functional interface descriptor. This means that:
3531         * (i) parameter types must be identical to those of the target descriptor; (ii) return
3532         * types must be compatible with the return type of the expected descriptor.
3533         */
3534         void checkLambdaCompatible(JCLambda tree, Type descriptor, CheckContext checkContext) {
3535             Type returnType = checkContext.inferenceContext().asUndetVar(descriptor.getReturnType());
3536 
3537             //return values have already been checked - but if lambda has no return
3538             //values, we must ensure that void/value compatibility is correct;
3539             //this amounts at checking that, if a lambda body can complete normally,
3540             //the descriptor's return type must be void
3541             if (tree.getBodyKind() == JCLambda.BodyKind.STATEMENT && tree.canCompleteNormally &&
3542                     !returnType.hasTag(VOID) && returnType != Type.recoveryType) {
3543                 Fragment msg =
3544                         Fragments.IncompatibleRetTypeInLambda(Fragments.MissingRetVal(returnType));
3545                 checkContext.report(tree,
3546                                     diags.fragment(msg));
3547             }
3548 
3549             List<Type> argTypes = checkContext.inferenceContext().asUndetVars(descriptor.getParameterTypes());
3550             if (!types.isSameTypes(argTypes, TreeInfo.types(tree.params))) {
3551                 checkContext.report(tree, diags.fragment(Fragments.IncompatibleArgTypesInLambda));
3552             }
3553         }
3554 
3555         /* Map to hold 'fake' clinit methods. If a lambda is used to initialize a
3556          * static field and that lambda has type annotations, these annotations will
3557          * also be stored at these fake clinit methods.
3558          *
3559          * LambdaToMethod also use fake clinit methods so they can be reused.
3560          * Also as LTM is a phase subsequent to attribution, the methods from
3561          * clinits can be safely removed by LTM to save memory.
3562          */
3563         private Map<ClassSymbol, MethodSymbol> clinits = new HashMap<>();
3564 
3565         public MethodSymbol removeClinit(ClassSymbol sym) {
3566             return clinits.remove(sym);
3567         }
3568 
3569         /* This method returns an environment to be used to attribute a lambda
3570          * expression.
3571          *
3572          * The owner of this environment is a method symbol. If the current owner
3573          * is not a method, for example if the lambda is used to initialize
3574          * a field, then if the field is:
3575          *
3576          * - an instance field, we use the first constructor.
3577          * - a static field, we create a fake clinit method.
3578          */
3579         public Env<AttrContext> lambdaEnv(JCLambda that, Env<AttrContext> env) {
3580             Env<AttrContext> lambdaEnv;
3581             Symbol owner = env.info.scope.owner;
3582             if (owner.kind == VAR && owner.owner.kind == TYP) {
3583                 //field initializer
3584                 ClassSymbol enclClass = owner.enclClass();
3585                 Symbol newScopeOwner = env.info.scope.owner;
3586                 /* if the field isn't static, then we can get the first constructor
3587                  * and use it as the owner of the environment. This is what
3588                  * LTM code is doing to look for type annotations so we are fine.
3589                  */
3590                 if ((owner.flags() & STATIC) == 0) {
3591                     for (Symbol s : enclClass.members_field.getSymbolsByName(names.init)) {
3592                         newScopeOwner = s;
3593                         break;
3594                     }
3595                 } else {
3596                     /* if the field is static then we need to create a fake clinit
3597                      * method, this method can later be reused by LTM.
3598                      */
3599                     MethodSymbol clinit = clinits.get(enclClass);
3600                     if (clinit == null) {
3601                         Type clinitType = new MethodType(List.nil(),
3602                                 syms.voidType, List.nil(), syms.methodClass);
3603                         clinit = new MethodSymbol(STATIC | SYNTHETIC | PRIVATE,
3604                                 names.clinit, clinitType, enclClass);
3605                         clinit.params = List.nil();
3606                         clinits.put(enclClass, clinit);
3607                     }
3608                     newScopeOwner = clinit;
3609                 }
3610                 lambdaEnv = env.dup(that, env.info.dup(env.info.scope.dupUnshared(newScopeOwner)));
3611             } else {
3612                 lambdaEnv = env.dup(that, env.info.dup(env.info.scope.dup()));
3613             }
3614             lambdaEnv.info.yieldResult = null;
3615             lambdaEnv.info.isLambda = true;
3616             return lambdaEnv;
3617         }
3618 
3619     @Override
3620     public void visitReference(final JCMemberReference that) {
3621         if (pt().isErroneous() || (pt().hasTag(NONE) && pt() != Type.recoveryType)) {
3622             if (pt().hasTag(NONE) && (env.info.enclVar == null || !env.info.enclVar.type.isErroneous())) {
3623                 //method reference only allowed in assignment or method invocation/cast context
3624                 log.error(that.pos(), Errors.UnexpectedMref);
3625             }
3626             result = that.type = types.createErrorType(pt());
3627             return;
3628         }
3629         final Env<AttrContext> localEnv = env.dup(that);
3630         try {
3631             //attribute member reference qualifier - if this is a constructor
3632             //reference, the expected kind must be a type
3633             Type exprType = attribTree(that.expr, env, memberReferenceQualifierResult(that));
3634 
3635             if (that.getMode() == JCMemberReference.ReferenceMode.NEW) {
3636                 exprType = chk.checkConstructorRefType(that.expr, exprType);
3637                 if (!exprType.isErroneous() &&
3638                     exprType.isRaw() &&
3639                     that.typeargs != null) {
3640                     log.error(that.expr.pos(),
3641                               Errors.InvalidMref(Kinds.kindName(that.getMode()),
3642                                                  Fragments.MrefInferAndExplicitParams));
3643                     exprType = types.createErrorType(exprType);
3644                 }
3645             }
3646 
3647             if (exprType.isErroneous()) {
3648                 //if the qualifier expression contains problems,
3649                 //give up attribution of method reference
3650                 result = that.type = exprType;
3651                 return;
3652             }
3653 
3654             if (TreeInfo.isStaticSelector(that.expr, names)) {
3655                 //if the qualifier is a type, validate it; raw warning check is
3656                 //omitted as we don't know at this stage as to whether this is a
3657                 //raw selector (because of inference)
3658                 chk.validate(that.expr, env, false);
3659             } else {
3660                 Symbol lhsSym = TreeInfo.symbol(that.expr);
3661                 localEnv.info.selectSuper = lhsSym != null && lhsSym.name == names._super;
3662             }
3663             //attrib type-arguments
3664             List<Type> typeargtypes = List.nil();
3665             if (that.typeargs != null) {
3666                 typeargtypes = attribTypes(that.typeargs, localEnv);
3667             }
3668 
3669             boolean isTargetSerializable =
3670                     resultInfo.checkContext.deferredAttrContext().mode == DeferredAttr.AttrMode.CHECK &&
3671                     rs.isSerializable(pt());
3672             TargetInfo targetInfo = getTargetInfo(that, resultInfo, null);
3673             Type currentTarget = targetInfo.target;
3674             Type desc = targetInfo.descriptor;
3675 
3676             setFunctionalInfo(localEnv, that, pt(), desc, currentTarget, resultInfo.checkContext);
3677             List<Type> argtypes = desc.getParameterTypes();
3678             Resolve.MethodCheck referenceCheck = rs.resolveMethodCheck;
3679 
3680             if (resultInfo.checkContext.inferenceContext().free(argtypes)) {
3681                 referenceCheck = rs.new MethodReferenceCheck(resultInfo.checkContext.inferenceContext());
3682             }
3683 
3684             Pair<Symbol, Resolve.ReferenceLookupHelper> refResult = null;
3685             List<Type> saved_undet = resultInfo.checkContext.inferenceContext().save();
3686             try {
3687                 refResult = rs.resolveMemberReference(localEnv, that, that.expr.type,
3688                         that.name, argtypes, typeargtypes, targetInfo.descriptor, referenceCheck,
3689                         resultInfo.checkContext.inferenceContext(), rs.basicReferenceChooser);
3690             } finally {
3691                 resultInfo.checkContext.inferenceContext().rollback(saved_undet);
3692             }
3693 
3694             Symbol refSym = refResult.fst;
3695             Resolve.ReferenceLookupHelper lookupHelper = refResult.snd;
3696 
3697             /** this switch will need to go away and be replaced by the new RESOLUTION_TARGET testing
3698              *  JDK-8075541
3699              */
3700             if (refSym.kind != MTH) {
3701                 boolean targetError;
3702                 switch (refSym.kind) {
3703                     case ABSENT_MTH:
3704                     case MISSING_ENCL:
3705                         targetError = false;
3706                         break;
3707                     case WRONG_MTH:
3708                     case WRONG_MTHS:
3709                     case AMBIGUOUS:
3710                     case HIDDEN:
3711                     case STATICERR:
3712                         targetError = true;
3713                         break;
3714                     default:
3715                         Assert.error("unexpected result kind " + refSym.kind);
3716                         targetError = false;
3717                 }
3718 
3719                 JCDiagnostic detailsDiag = ((Resolve.ResolveError)refSym.baseSymbol())
3720                         .getDiagnostic(JCDiagnostic.DiagnosticType.FRAGMENT,
3721                                 that, exprType.tsym, exprType, that.name, argtypes, typeargtypes);
3722 
3723                 JCDiagnostic diag = diags.create(log.currentSource(), that,
3724                         targetError ?
3725                             Fragments.InvalidMref(Kinds.kindName(that.getMode()), detailsDiag) :
3726                             Errors.InvalidMref(Kinds.kindName(that.getMode()), detailsDiag));
3727 
3728                 if (targetError && currentTarget == Type.recoveryType) {
3729                     //a target error doesn't make sense during recovery stage
3730                     //as we don't know what actual parameter types are
3731                     result = that.type = currentTarget;
3732                     return;
3733                 } else {
3734                     if (targetError) {
3735                         resultInfo.checkContext.report(that, diag);
3736                     } else {
3737                         log.report(diag);
3738                     }
3739                     result = that.type = types.createErrorType(currentTarget);
3740                     return;
3741                 }
3742             }
3743 
3744             that.sym = refSym.isConstructor() ? refSym.baseSymbol() : refSym;
3745             that.kind = lookupHelper.referenceKind(that.sym);
3746             that.ownerAccessible = rs.isAccessible(localEnv, that.sym.enclClass());
3747 
3748             if (desc.getReturnType() == Type.recoveryType) {
3749                 // stop here
3750                 result = that.type = currentTarget;
3751                 return;
3752             }
3753 
3754             if (!env.info.attributionMode.isSpeculative && that.getMode() == JCMemberReference.ReferenceMode.NEW) {
3755                 Type enclosingType = exprType.getEnclosingType();
3756                 if (enclosingType != null && enclosingType.hasTag(CLASS)) {
3757                     // Check for the existence of an appropriate outer instance
3758                     rs.resolveImplicitThis(that.pos(), env, exprType);
3759                 }
3760             }
3761 
3762             if (resultInfo.checkContext.deferredAttrContext().mode == AttrMode.CHECK) {
3763 
3764                 if (that.getMode() == ReferenceMode.INVOKE &&
3765                         TreeInfo.isStaticSelector(that.expr, names) &&
3766                         that.kind.isUnbound() &&
3767                         lookupHelper.site.isRaw()) {
3768                     chk.checkRaw(that.expr, localEnv);
3769                 }
3770 
3771                 if (that.sym.isStatic() && TreeInfo.isStaticSelector(that.expr, names) &&
3772                         exprType.getTypeArguments().nonEmpty()) {
3773                     //static ref with class type-args
3774                     log.error(that.expr.pos(),
3775                               Errors.InvalidMref(Kinds.kindName(that.getMode()),
3776                                                  Fragments.StaticMrefWithTargs));
3777                     result = that.type = types.createErrorType(currentTarget);
3778                     return;
3779                 }
3780 
3781                 if (!refSym.isStatic() && that.kind == JCMemberReference.ReferenceKind.SUPER) {
3782                     // Check that super-qualified symbols are not abstract (JLS)
3783                     rs.checkNonAbstract(that.pos(), that.sym);
3784                 }
3785 
3786                 if (isTargetSerializable) {
3787                     chk.checkAccessFromSerializableElement(that, true);
3788                 }
3789             }
3790 
3791             ResultInfo checkInfo =
3792                     resultInfo.dup(newMethodTemplate(
3793                         desc.getReturnType().hasTag(VOID) ? Type.noType : desc.getReturnType(),
3794                         that.kind.isUnbound() ? argtypes.tail : argtypes, typeargtypes),
3795                         new FunctionalReturnContext(resultInfo.checkContext), CheckMode.NO_TREE_UPDATE);
3796 
3797             Type refType = checkId(that, lookupHelper.site, refSym, localEnv, checkInfo);
3798 
3799             if (that.kind.isUnbound() &&
3800                     resultInfo.checkContext.inferenceContext().free(argtypes.head)) {
3801                 //re-generate inference constraints for unbound receiver
3802                 if (!types.isSubtype(resultInfo.checkContext.inferenceContext().asUndetVar(argtypes.head), exprType)) {
3803                     //cannot happen as this has already been checked - we just need
3804                     //to regenerate the inference constraints, as that has been lost
3805                     //as a result of the call to inferenceContext.save()
3806                     Assert.error("Can't get here");
3807                 }
3808             }
3809 
3810             if (!refType.isErroneous()) {
3811                 refType = types.createMethodTypeWithReturn(refType,
3812                         adjustMethodReturnType(refSym, lookupHelper.site, that.name, checkInfo.pt.getParameterTypes(), refType.getReturnType()));
3813             }
3814 
3815             //go ahead with standard method reference compatibility check - note that param check
3816             //is a no-op (as this has been taken care during method applicability)
3817             boolean isSpeculativeRound =
3818                     resultInfo.checkContext.deferredAttrContext().mode == DeferredAttr.AttrMode.SPECULATIVE;
3819 
3820             that.type = currentTarget; //avoids recovery at this stage
3821             checkReferenceCompatible(that, desc, refType, resultInfo.checkContext, isSpeculativeRound);
3822             if (!isSpeculativeRound) {
3823                 checkAccessibleTypes(that, localEnv, resultInfo.checkContext.inferenceContext(), desc, currentTarget);
3824             }
3825             result = check(that, currentTarget, KindSelector.VAL, resultInfo);
3826         } catch (Types.FunctionDescriptorLookupError ex) {
3827             JCDiagnostic cause = ex.getDiagnostic();
3828             resultInfo.checkContext.report(that, cause);
3829             result = that.type = types.createErrorType(pt());
3830             return;
3831         }
3832     }
3833     //where
3834         ResultInfo memberReferenceQualifierResult(JCMemberReference tree) {
3835             //if this is a constructor reference, the expected kind must be a type
3836             return new ResultInfo(tree.getMode() == ReferenceMode.INVOKE ?
3837                                   KindSelector.VAL_TYP : KindSelector.TYP,
3838                                   Type.noType);
3839         }
3840 
3841 
3842     @SuppressWarnings("fallthrough")
3843     void checkReferenceCompatible(JCMemberReference tree, Type descriptor, Type refType, CheckContext checkContext, boolean speculativeAttr) {
3844         InferenceContext inferenceContext = checkContext.inferenceContext();
3845         Type returnType = inferenceContext.asUndetVar(descriptor.getReturnType());
3846 
3847         Type resType;
3848         switch (tree.getMode()) {
3849             case NEW:
3850                 if (!tree.expr.type.isRaw()) {
3851                     resType = tree.expr.type;
3852                     break;
3853                 }
3854             default:
3855                 resType = refType.getReturnType();
3856         }
3857 
3858         Type incompatibleReturnType = resType;
3859 
3860         if (returnType.hasTag(VOID)) {
3861             incompatibleReturnType = null;
3862         }
3863 
3864         if (!returnType.hasTag(VOID) && !resType.hasTag(VOID)) {
3865             if (resType.isErroneous() ||
3866                     new FunctionalReturnContext(checkContext).compatible(resType, returnType,
3867                             checkContext.checkWarner(tree, resType, returnType))) {
3868                 incompatibleReturnType = null;
3869             }
3870         }
3871 
3872         if (incompatibleReturnType != null) {
3873             Fragment msg =
3874                     Fragments.IncompatibleRetTypeInMref(Fragments.InconvertibleTypes(resType, descriptor.getReturnType()));
3875             checkContext.report(tree, diags.fragment(msg));
3876         } else {
3877             if (inferenceContext.free(refType)) {
3878                 // we need to wait for inference to finish and then replace inference vars in the referent type
3879                 inferenceContext.addFreeTypeListener(List.of(refType),
3880                         instantiatedContext -> {
3881                             tree.referentType = instantiatedContext.asInstType(refType);
3882                         });
3883             } else {
3884                 tree.referentType = refType;
3885             }
3886         }
3887 
3888         if (!speculativeAttr) {
3889             if (!checkExConstraints(refType.getThrownTypes(), descriptor.getThrownTypes(), inferenceContext)) {
3890                 log.error(tree, Errors.IncompatibleThrownTypesInMref(refType.getThrownTypes()));
3891             }
3892         }
3893     }
3894 
3895     boolean checkExConstraints(
3896             List<Type> thrownByFuncExpr,
3897             List<Type> thrownAtFuncType,
3898             InferenceContext inferenceContext) {
3899         /** 18.2.5: Otherwise, let E1, ..., En be the types in the function type's throws clause that
3900          *  are not proper types
3901          */
3902         List<Type> nonProperList = thrownAtFuncType.stream()
3903                 .filter(e -> inferenceContext.free(e)).collect(List.collector());
3904         List<Type> properList = thrownAtFuncType.diff(nonProperList);
3905 
3906         /** Let X1,...,Xm be the checked exception types that the lambda body can throw or
3907          *  in the throws clause of the invocation type of the method reference's compile-time
3908          *  declaration
3909          */
3910         List<Type> checkedList = thrownByFuncExpr.stream()
3911                 .filter(e -> chk.isChecked(e)).collect(List.collector());
3912 
3913         /** If n = 0 (the function type's throws clause consists only of proper types), then
3914          *  if there exists some i (1 <= i <= m) such that Xi is not a subtype of any proper type
3915          *  in the throws clause, the constraint reduces to false; otherwise, the constraint
3916          *  reduces to true
3917          */
3918         ListBuffer<Type> uncaughtByProperTypes = new ListBuffer<>();
3919         for (Type checked : checkedList) {
3920             boolean isSubtype = false;
3921             for (Type proper : properList) {
3922                 if (types.isSubtype(checked, proper)) {
3923                     isSubtype = true;
3924                     break;
3925                 }
3926             }
3927             if (!isSubtype) {
3928                 uncaughtByProperTypes.add(checked);
3929             }
3930         }
3931 
3932         if (nonProperList.isEmpty() && !uncaughtByProperTypes.isEmpty()) {
3933             return false;
3934         }
3935 
3936         /** If n > 0, the constraint reduces to a set of subtyping constraints:
3937          *  for all i (1 <= i <= m), if Xi is not a subtype of any proper type in the
3938          *  throws clause, then the constraints include, for all j (1 <= j <= n), <Xi <: Ej>
3939          */
3940         List<Type> nonProperAsUndet = inferenceContext.asUndetVars(nonProperList);
3941         uncaughtByProperTypes.forEach(checkedEx -> {
3942             nonProperAsUndet.forEach(nonProper -> {
3943                 types.isSubtype(checkedEx, nonProper);
3944             });
3945         });
3946 
3947         /** In addition, for all j (1 <= j <= n), the constraint reduces to the bound throws Ej
3948          */
3949         nonProperAsUndet.stream()
3950                 .filter(t -> t.hasTag(UNDETVAR))
3951                 .forEach(t -> ((UndetVar)t).setThrow());
3952         return true;
3953     }
3954 
3955     /**
3956      * Set functional type info on the underlying AST. Note: as the target descriptor
3957      * might contain inference variables, we might need to register an hook in the
3958      * current inference context.
3959      */
3960     private void setFunctionalInfo(final Env<AttrContext> env, final JCFunctionalExpression fExpr,
3961             final Type pt, final Type descriptorType, final Type primaryTarget, final CheckContext checkContext) {
3962         if (checkContext.inferenceContext().free(descriptorType)) {
3963             checkContext.inferenceContext().addFreeTypeListener(List.of(pt, descriptorType),
3964                     inferenceContext -> setFunctionalInfo(env, fExpr, pt, inferenceContext.asInstType(descriptorType),
3965                     inferenceContext.asInstType(primaryTarget), checkContext));
3966         } else {
3967             if (pt.hasTag(CLASS)) {
3968                 fExpr.target = primaryTarget;
3969             }
3970             if (checkContext.deferredAttrContext().mode == DeferredAttr.AttrMode.CHECK &&
3971                     pt != Type.recoveryType) {
3972                 //check that functional interface class is well-formed
3973                 try {
3974                     /* Types.makeFunctionalInterfaceClass() may throw an exception
3975                      * when it's executed post-inference. See the listener code
3976                      * above.
3977                      */
3978                     ClassSymbol csym = types.makeFunctionalInterfaceClass(env,
3979                             names.empty, fExpr.target, ABSTRACT);
3980                     if (csym != null) {
3981                         chk.checkImplementations(env.tree, csym, csym);
3982                         try {
3983                             //perform an additional functional interface check on the synthetic class,
3984                             //as there may be spurious errors for raw targets - because of existing issues
3985                             //with membership and inheritance (see JDK-8074570).
3986                             csym.flags_field |= INTERFACE;
3987                             types.findDescriptorType(csym.type);
3988                         } catch (FunctionDescriptorLookupError err) {
3989                             resultInfo.checkContext.report(fExpr,
3990                                     diags.fragment(Fragments.NoSuitableFunctionalIntfInst(fExpr.target)));
3991                         }
3992                     }
3993                 } catch (Types.FunctionDescriptorLookupError ex) {
3994                     JCDiagnostic cause = ex.getDiagnostic();
3995                     resultInfo.checkContext.report(env.tree, cause);
3996                 }
3997             }
3998         }
3999     }
4000 
4001     public void visitParens(JCParens tree) {
4002         Type owntype = attribTree(tree.expr, env, resultInfo);
4003         result = check(tree, owntype, pkind(), resultInfo);
4004         Symbol sym = TreeInfo.symbol(tree);
4005         if (sym != null && sym.kind.matches(KindSelector.TYP_PCK) && sym.kind != Kind.ERR)
4006             log.error(tree.pos(), Errors.IllegalParenthesizedExpression);
4007     }
4008 
4009     public void visitAssign(JCAssign tree) {
4010         Type owntype = attribTree(tree.lhs, env.dup(tree), varAssignmentInfo);
4011         Type capturedType = capture(owntype);
4012         attribExpr(tree.rhs, env, owntype);
4013         result = check(tree, capturedType, KindSelector.VAL, resultInfo);
4014     }
4015 
4016     public void visitAssignop(JCAssignOp tree) {
4017         // Attribute arguments.
4018         Type owntype = attribTree(tree.lhs, env, varAssignmentInfo);
4019         Type operand = attribExpr(tree.rhs, env);
4020         // Find operator.
4021         Symbol operator = tree.operator = operators.resolveBinary(tree, tree.getTag().noAssignOp(), owntype, operand);
4022         if (operator != operators.noOpSymbol &&
4023                 !owntype.isErroneous() &&
4024                 !operand.isErroneous()) {
4025             chk.checkDivZero(tree.rhs.pos(), operator, operand);
4026             chk.checkCastable(tree.rhs.pos(),
4027                               operator.type.getReturnType(),
4028                               owntype);
4029             chk.checkLossOfPrecision(tree.rhs.pos(), operand, owntype);
4030         }
4031         result = check(tree, owntype, KindSelector.VAL, resultInfo);
4032     }
4033 
4034     public void visitUnary(JCUnary tree) {
4035         // Attribute arguments.
4036         Type argtype = (tree.getTag().isIncOrDecUnaryOp())
4037             ? attribTree(tree.arg, env, varAssignmentInfo)
4038             : chk.checkNonVoid(tree.arg.pos(), attribExpr(tree.arg, env));
4039 
4040         // Find operator.
4041         OperatorSymbol operator = tree.operator = operators.resolveUnary(tree, tree.getTag(), argtype);
4042         Type owntype = types.createErrorType(tree.type);
4043         if (operator != operators.noOpSymbol &&
4044                 !argtype.isErroneous()) {
4045             owntype = (tree.getTag().isIncOrDecUnaryOp())
4046                 ? tree.arg.type
4047                 : operator.type.getReturnType();
4048             int opc = operator.opcode;
4049 
4050             // If the argument is constant, fold it.
4051             if (argtype.constValue() != null) {
4052                 Type ctype = cfolder.fold1(opc, argtype);
4053                 if (ctype != null) {
4054                     owntype = cfolder.coerce(ctype, owntype);
4055                 }
4056             }
4057         }
4058         result = check(tree, owntype, KindSelector.VAL, resultInfo);
4059         matchBindings = matchBindingsComputer.unary(tree, matchBindings);
4060     }
4061 
4062     public void visitBinary(JCBinary tree) {
4063         // Attribute arguments.
4064         Type left = chk.checkNonVoid(tree.lhs.pos(), attribExpr(tree.lhs, env));
4065         // x && y
4066         // include x's bindings when true in y
4067 
4068         // x || y
4069         // include x's bindings when false in y
4070 
4071         MatchBindings lhsBindings = matchBindings;
4072         List<BindingSymbol> propagatedBindings;
4073         switch (tree.getTag()) {
4074             case AND:
4075                 propagatedBindings = lhsBindings.bindingsWhenTrue;
4076                 break;
4077             case OR:
4078                 propagatedBindings = lhsBindings.bindingsWhenFalse;
4079                 break;
4080             default:
4081                 propagatedBindings = List.nil();
4082                 break;
4083         }
4084         Env<AttrContext> rhsEnv = bindingEnv(env, propagatedBindings);
4085         Type right;
4086         try {
4087             right = chk.checkNonVoid(tree.rhs.pos(), attribExpr(tree.rhs, rhsEnv));
4088         } finally {
4089             rhsEnv.info.scope.leave();
4090         }
4091 
4092         matchBindings = matchBindingsComputer.binary(tree, lhsBindings, matchBindings);
4093 
4094         // Find operator.
4095         OperatorSymbol operator = tree.operator = operators.resolveBinary(tree, tree.getTag(), left, right);
4096         Type owntype = types.createErrorType(tree.type);
4097         if (operator != operators.noOpSymbol &&
4098                 !left.isErroneous() &&
4099                 !right.isErroneous()) {
4100             owntype = operator.type.getReturnType();
4101             int opc = operator.opcode;
4102             // If both arguments are constants, fold them.
4103             if (left.constValue() != null && right.constValue() != null) {
4104                 Type ctype = cfolder.fold2(opc, left, right);
4105                 if (ctype != null) {
4106                     owntype = cfolder.coerce(ctype, owntype);
4107                 }
4108             }
4109 
4110             // Check that argument types of a reference ==, != are
4111             // castable to each other, (JLS 15.21).  Note: unboxing
4112             // comparisons will not have an acmp* opc at this point.
4113             if ((opc == ByteCodes.if_acmpeq || opc == ByteCodes.if_acmpne)) {
4114                 if (!types.isCastable(left, right, new Warner(tree.pos()))) {
4115                     log.error(tree.pos(), Errors.IncomparableTypes(left, right));
4116                 }
4117             }
4118 
4119             chk.checkDivZero(tree.rhs.pos(), operator, right);
4120         }
4121         result = check(tree, owntype, KindSelector.VAL, resultInfo);
4122     }
4123 
4124     public void visitTypeCast(final JCTypeCast tree) {
4125         Type clazztype = attribType(tree.clazz, env);
4126         chk.validate(tree.clazz, env, false);
4127         //a fresh environment is required for 292 inference to work properly ---
4128         //see Infer.instantiatePolymorphicSignatureInstance()
4129         Env<AttrContext> localEnv = env.dup(tree);
4130         //should we propagate the target type?
4131         final ResultInfo castInfo;
4132         JCExpression expr = TreeInfo.skipParens(tree.expr);
4133         boolean isPoly = (expr.hasTag(LAMBDA) || expr.hasTag(REFERENCE));
4134         if (isPoly) {
4135             //expression is a poly - we need to propagate target type info
4136             castInfo = new ResultInfo(KindSelector.VAL, clazztype,
4137                                       new Check.NestedCheckContext(resultInfo.checkContext) {
4138                 @Override
4139                 public boolean compatible(Type found, Type req, Warner warn) {
4140                     return types.isCastable(found, req, warn);
4141                 }
4142             });
4143         } else {
4144             //standalone cast - target-type info is not propagated
4145             castInfo = unknownExprInfo;
4146         }
4147         Type exprtype = attribTree(tree.expr, localEnv, castInfo);
4148         Type owntype = isPoly ? clazztype : chk.checkCastable(tree.expr.pos(), exprtype, clazztype);
4149         if (exprtype.constValue() != null)
4150             owntype = cfolder.coerce(exprtype, owntype);
4151         result = check(tree, capture(owntype), KindSelector.VAL, resultInfo);
4152         if (!isPoly)
4153             chk.checkRedundantCast(localEnv, tree);
4154     }
4155 
4156     public void visitTypeTest(JCInstanceOf tree) {
4157         Type exprtype = attribExpr(tree.expr, env);
4158         if (exprtype.isPrimitive()) {
4159             preview.checkSourceLevel(tree.expr.pos(), Feature.PRIMITIVE_PATTERNS);
4160         } else {
4161             exprtype = chk.checkNullOrRefType(
4162                     tree.expr.pos(), exprtype);
4163         }
4164         Type clazztype;
4165         JCTree typeTree;
4166         if (tree.pattern.getTag() == BINDINGPATTERN ||
4167             tree.pattern.getTag() == RECORDPATTERN) {
4168             attribExpr(tree.pattern, env, exprtype);
4169             clazztype = tree.pattern.type;
4170             if (types.isSubtype(exprtype, clazztype) &&
4171                 !exprtype.isErroneous() && !clazztype.isErroneous() &&
4172                 tree.pattern.getTag() != RECORDPATTERN) {
4173                 if (!allowUnconditionalPatternsInstanceOf) {
4174                     log.error(DiagnosticFlag.SOURCE_LEVEL, tree.pos(),
4175                               Feature.UNCONDITIONAL_PATTERN_IN_INSTANCEOF.error(this.sourceName));
4176                 }
4177             }
4178             typeTree = TreeInfo.primaryPatternTypeTree((JCPattern) tree.pattern);
4179         } else {
4180             clazztype = attribType(tree.pattern, env);
4181             typeTree = tree.pattern;
4182             chk.validate(typeTree, env, false);
4183         }
4184         if (clazztype.isPrimitive()) {
4185             preview.checkSourceLevel(tree.pattern.pos(), Feature.PRIMITIVE_PATTERNS);
4186         } else {
4187             if (!clazztype.hasTag(TYPEVAR)) {
4188                 clazztype = chk.checkClassOrArrayType(typeTree.pos(), clazztype);
4189             }
4190             if (!clazztype.isErroneous() && !types.isReifiable(clazztype)) {
4191                 boolean valid = false;
4192                 if (allowReifiableTypesInInstanceof) {
4193                     valid = checkCastablePattern(tree.expr.pos(), exprtype, clazztype);
4194                 } else {
4195                     log.error(DiagnosticFlag.SOURCE_LEVEL, tree.pos(),
4196                             Feature.REIFIABLE_TYPES_INSTANCEOF.error(this.sourceName));
4197                     allowReifiableTypesInInstanceof = true;
4198                 }
4199                 if (!valid) {
4200                     clazztype = types.createErrorType(clazztype);
4201                 }
4202             }
4203         }
4204         chk.checkCastable(tree.expr.pos(), exprtype, clazztype);
4205         result = check(tree, syms.booleanType, KindSelector.VAL, resultInfo);
4206     }
4207 
4208     private boolean checkCastablePattern(DiagnosticPosition pos,
4209                                          Type exprType,
4210                                          Type pattType) {
4211         Warner warner = new Warner();
4212         // if any type is erroneous, the problem is reported elsewhere
4213         if (exprType.isErroneous() || pattType.isErroneous()) {
4214             return false;
4215         }
4216         if (!types.isCastable(exprType, pattType, warner)) {
4217             chk.basicHandler.report(pos,
4218                     diags.fragment(Fragments.InconvertibleTypes(exprType, pattType)));
4219             return false;
4220         } else if ((exprType.isPrimitive() || pattType.isPrimitive()) &&
4221                 (!exprType.isPrimitive() || !pattType.isPrimitive() || !types.isSameType(exprType, pattType))) {
4222             preview.checkSourceLevel(pos, Feature.PRIMITIVE_PATTERNS);
4223             return true;
4224         } else if (warner.hasLint(LintCategory.UNCHECKED)) {
4225             log.error(pos,
4226                     Errors.InstanceofReifiableNotSafe(exprType, pattType));
4227             return false;
4228         } else {
4229             return true;
4230         }
4231     }
4232 
4233     @Override
4234     public void visitAnyPattern(JCAnyPattern tree) {
4235         result = tree.type = resultInfo.pt;
4236     }
4237 
4238     public void visitBindingPattern(JCBindingPattern tree) {
4239         Type type;
4240         if (tree.var.vartype != null) {
4241             type = attribType(tree.var.vartype, env);
4242         } else {
4243             type = resultInfo.pt;
4244         }
4245         tree.type = tree.var.type = type;
4246         BindingSymbol v = new BindingSymbol(tree.var.mods.flags, tree.var.name, type, env.info.scope.owner);
4247         v.pos = tree.pos;
4248         tree.var.sym = v;
4249         if (chk.checkUnique(tree.var.pos(), v, env.info.scope)) {
4250             chk.checkTransparentVar(tree.var.pos(), v, env.info.scope);
4251         }
4252         if (tree.var.isImplicitlyTyped()) {
4253             setSyntheticVariableType(tree.var, type == Type.noType ? syms.errType
4254                                                                    : type);
4255         }
4256         annotate.annotateLater(tree.var.mods.annotations, env, v, tree.pos());
4257         if (!tree.var.isImplicitlyTyped()) {
4258             annotate.queueScanTreeAndTypeAnnotate(tree.var.vartype, env, v, tree.var.pos());
4259         }
4260         annotate.flush();
4261         chk.validate(tree.var.vartype, env, true);
4262         result = tree.type;
4263         if (v.isUnnamedVariable()) {
4264             matchBindings = MatchBindingsComputer.EMPTY;
4265         } else {
4266             matchBindings = new MatchBindings(List.of(v), List.nil());
4267         }
4268     }
4269 
4270     @Override
4271     public void visitRecordPattern(JCRecordPattern tree) {
4272         Type site;
4273 
4274         if (tree.deconstructor == null) {
4275             log.error(tree.pos(), Errors.DeconstructionPatternVarNotAllowed);
4276             tree.record = syms.errSymbol;
4277             site = tree.type = types.createErrorType(tree.record.type);
4278         } else {
4279             Type type = attribType(tree.deconstructor, env);
4280             if (type.isRaw() && type.tsym.getTypeParameters().nonEmpty()) {
4281                 Type inferred = infer.instantiatePatternType(resultInfo.pt, type.tsym);
4282                 if (inferred == null) {
4283                     log.error(tree.pos(), Errors.PatternTypeCannotInfer);
4284                 } else {
4285                     type = inferred;
4286                 }
4287             }
4288             tree.type = tree.deconstructor.type = type;
4289             site = types.capture(tree.type);
4290         }
4291 
4292         List<Type> expectedRecordTypes;
4293         if (site.tsym.kind == Kind.TYP && ((ClassSymbol) site.tsym).isRecord()) {
4294             ClassSymbol record = (ClassSymbol) site.tsym;
4295             expectedRecordTypes = record.getRecordComponents()
4296                                         .stream()
4297                                         .map(rc -> types.memberType(site, rc))
4298                                         .map(t -> types.upward(t, types.captures(t)).baseType())
4299                                         .collect(List.collector());
4300             tree.record = record;
4301         } else {
4302             log.error(tree.pos(), Errors.DeconstructionPatternOnlyRecords(site.tsym));
4303             expectedRecordTypes = Stream.generate(() -> types.createErrorType(tree.type))
4304                                 .limit(tree.nested.size())
4305                                 .collect(List.collector());
4306             tree.record = syms.errSymbol;
4307         }
4308         ListBuffer<BindingSymbol> outBindings = new ListBuffer<>();
4309         List<Type> recordTypes = expectedRecordTypes;
4310         List<JCPattern> nestedPatterns = tree.nested;
4311         Env<AttrContext> localEnv = env.dup(tree, env.info.dup(env.info.scope.dup()));
4312         try {
4313             while (recordTypes.nonEmpty() && nestedPatterns.nonEmpty()) {
4314                 attribExpr(nestedPatterns.head, localEnv, recordTypes.head);
4315                 checkCastablePattern(nestedPatterns.head.pos(), recordTypes.head, nestedPatterns.head.type);
4316                 outBindings.addAll(matchBindings.bindingsWhenTrue);
4317                 matchBindings.bindingsWhenTrue.forEach(localEnv.info.scope::enter);
4318                 nestedPatterns = nestedPatterns.tail;
4319                 recordTypes = recordTypes.tail;
4320             }
4321             if (recordTypes.nonEmpty() || nestedPatterns.nonEmpty()) {
4322                 while (nestedPatterns.nonEmpty()) {
4323                     attribExpr(nestedPatterns.head, localEnv, Type.noType);
4324                     nestedPatterns = nestedPatterns.tail;
4325                 }
4326                 List<Type> nestedTypes =
4327                         tree.nested.stream().map(p -> p.type).collect(List.collector());
4328                 log.error(tree.pos(),
4329                           Errors.IncorrectNumberOfNestedPatterns(expectedRecordTypes,
4330                                                                  nestedTypes));
4331             }
4332         } finally {
4333             localEnv.info.scope.leave();
4334         }
4335         chk.validate(tree.deconstructor, env, true);
4336         result = tree.type;
4337         matchBindings = new MatchBindings(outBindings.toList(), List.nil());
4338     }
4339 
4340     public void visitIndexed(JCArrayAccess tree) {
4341         Type owntype = types.createErrorType(tree.type);
4342         Type atype = attribExpr(tree.indexed, env);
4343         attribExpr(tree.index, env, syms.intType);
4344         if (types.isArray(atype))
4345             owntype = types.elemtype(atype);
4346         else if (!atype.hasTag(ERROR))
4347             log.error(tree.pos(), Errors.ArrayReqButFound(atype));
4348         if (!pkind().contains(KindSelector.VAL))
4349             owntype = capture(owntype);
4350         result = check(tree, owntype, KindSelector.VAR, resultInfo);
4351     }
4352 
4353     public void visitIdent(JCIdent tree) {
4354         Symbol sym;
4355 
4356         // Find symbol
4357         if (pt().hasTag(METHOD) || pt().hasTag(FORALL)) {
4358             // If we are looking for a method, the prototype `pt' will be a
4359             // method type with the type of the call's arguments as parameters.
4360             env.info.pendingResolutionPhase = null;
4361             sym = rs.resolveMethod(tree.pos(), env, tree.name, pt().getParameterTypes(), pt().getTypeArguments());
4362         } else if (tree.sym != null && tree.sym.kind != VAR) {
4363             sym = tree.sym;
4364         } else {
4365             sym = rs.resolveIdent(tree.pos(), env, tree.name, pkind());
4366         }
4367         tree.sym = sym;
4368 
4369         // Also find the environment current for the class where
4370         // sym is defined (`symEnv').
4371         Env<AttrContext> symEnv = env;
4372         if (env.enclClass.sym.owner.kind != PCK && // we are in an inner class
4373             sym.kind.matches(KindSelector.VAL_MTH) &&
4374             sym.owner.kind == TYP &&
4375             tree.name != names._this && tree.name != names._super) {
4376 
4377             // Find environment in which identifier is defined.
4378             while (symEnv.outer != null &&
4379                    !sym.isMemberOf(symEnv.enclClass.sym, types)) {
4380                 symEnv = symEnv.outer;
4381             }
4382         }
4383 
4384         // If symbol is a variable, ...
4385         if (sym.kind == VAR) {
4386             VarSymbol v = (VarSymbol)sym;
4387 
4388             // ..., evaluate its initializer, if it has one, and check for
4389             // illegal forward reference.
4390             checkInit(tree, env, v, false);
4391 
4392             // If we are expecting a variable (as opposed to a value), check
4393             // that the variable is assignable in the current environment.
4394             if (KindSelector.ASG.subset(pkind()))
4395                 checkAssignable(tree.pos(), v, null, env);
4396         }
4397 
4398         Env<AttrContext> env1 = env;
4399         if (sym.kind != ERR && sym.kind != TYP &&
4400             sym.owner != null && sym.owner != env1.enclClass.sym) {
4401             // If the found symbol is inaccessible, then it is
4402             // accessed through an enclosing instance.  Locate this
4403             // enclosing instance:
4404             while (env1.outer != null && !rs.isAccessible(env, env1.enclClass.sym.type, sym))
4405                 env1 = env1.outer;
4406         }
4407 
4408         if (env.info.isSerializable) {
4409             chk.checkAccessFromSerializableElement(tree, env.info.isSerializableLambda);
4410         }
4411 
4412         result = checkId(tree, env1.enclClass.sym.type, sym, env, resultInfo);
4413     }
4414 
4415     public void visitSelect(JCFieldAccess tree) {
4416         // Determine the expected kind of the qualifier expression.
4417         KindSelector skind = KindSelector.NIL;
4418         if (tree.name == names._this || tree.name == names._super ||
4419                 tree.name == names._class)
4420         {
4421             skind = KindSelector.TYP;
4422         } else {
4423             if (pkind().contains(KindSelector.PCK))
4424                 skind = KindSelector.of(skind, KindSelector.PCK);
4425             if (pkind().contains(KindSelector.TYP))
4426                 skind = KindSelector.of(skind, KindSelector.TYP, KindSelector.PCK);
4427             if (pkind().contains(KindSelector.VAL_MTH))
4428                 skind = KindSelector.of(skind, KindSelector.VAL, KindSelector.TYP);
4429         }
4430 
4431         // Attribute the qualifier expression, and determine its symbol (if any).
4432         Type site = attribTree(tree.selected, env, new ResultInfo(skind, Type.noType));
4433         Assert.check(site == tree.selected.type);
4434         if (!pkind().contains(KindSelector.TYP_PCK))
4435             site = capture(site); // Capture field access
4436 
4437         // don't allow T.class T[].class, etc
4438         if (skind == KindSelector.TYP) {
4439             Type elt = site;
4440             while (elt.hasTag(ARRAY))
4441                 elt = ((ArrayType)elt).elemtype;
4442             if (elt.hasTag(TYPEVAR)) {
4443                 log.error(tree.pos(), Errors.TypeVarCantBeDeref);
4444                 result = tree.type = types.createErrorType(tree.name, site.tsym, site);
4445                 tree.sym = tree.type.tsym;
4446                 return ;
4447             }
4448         }
4449 
4450         // If qualifier symbol is a type or `super', assert `selectSuper'
4451         // for the selection. This is relevant for determining whether
4452         // protected symbols are accessible.
4453         Symbol sitesym = TreeInfo.symbol(tree.selected);
4454         boolean selectSuperPrev = env.info.selectSuper;
4455         env.info.selectSuper =
4456             sitesym != null &&
4457             sitesym.name == names._super;
4458 
4459         // Determine the symbol represented by the selection.
4460         env.info.pendingResolutionPhase = null;
4461         Symbol sym = selectSym(tree, sitesym, site, env, resultInfo);
4462         if (sym.kind == VAR && sym.name != names._super && env.info.defaultSuperCallSite != null) {
4463             log.error(tree.selected.pos(), Errors.NotEnclClass(site.tsym));
4464             sym = syms.errSymbol;
4465         }
4466         if (sym.exists() && !isType(sym) && pkind().contains(KindSelector.TYP_PCK)) {
4467             site = capture(site);
4468             sym = selectSym(tree, sitesym, site, env, resultInfo);
4469         }
4470         boolean varArgs = env.info.lastResolveVarargs();
4471         tree.sym = sym;
4472 
4473         if (site.hasTag(TYPEVAR) && !isType(sym) && sym.kind != ERR) {
4474             site = types.skipTypeVars(site, true);
4475         }
4476 
4477         // If that symbol is a variable, ...
4478         if (sym.kind == VAR) {
4479             VarSymbol v = (VarSymbol)sym;
4480 
4481             // ..., evaluate its initializer, if it has one, and check for
4482             // illegal forward reference.
4483             checkInit(tree, env, v, true);
4484 
4485             // If we are expecting a variable (as opposed to a value), check
4486             // that the variable is assignable in the current environment.
4487             if (KindSelector.ASG.subset(pkind()))
4488                 checkAssignable(tree.pos(), v, tree.selected, env);
4489         }
4490 
4491         if (sitesym != null &&
4492                 sitesym.kind == VAR &&
4493                 ((VarSymbol)sitesym).isResourceVariable() &&
4494                 sym.kind == MTH &&
4495                 sym.name.equals(names.close) &&
4496                 sym.overrides(syms.autoCloseableClose, sitesym.type.tsym, types, true) &&
4497                 env.info.lint.isEnabled(LintCategory.TRY)) {
4498             log.warning(LintCategory.TRY, tree, Warnings.TryExplicitCloseCall);
4499         }
4500 
4501         // Disallow selecting a type from an expression
4502         if (isType(sym) && (sitesym == null || !sitesym.kind.matches(KindSelector.TYP_PCK))) {
4503             tree.type = check(tree.selected, pt(),
4504                               sitesym == null ?
4505                                       KindSelector.VAL : sitesym.kind.toSelector(),
4506                               new ResultInfo(KindSelector.TYP_PCK, pt()));
4507         }
4508 
4509         if (isType(sitesym)) {
4510             if (sym.name != names._this && sym.name != names._super) {
4511                 // Check if type-qualified fields or methods are static (JLS)
4512                 if ((sym.flags() & STATIC) == 0 &&
4513                     sym.name != names._super &&
4514                     (sym.kind == VAR || sym.kind == MTH)) {
4515                     rs.accessBase(rs.new StaticError(sym),
4516                               tree.pos(), site, sym.name, true);
4517                 }
4518             }
4519         } else if (sym.kind != ERR &&
4520                    (sym.flags() & STATIC) != 0 &&
4521                    sym.name != names._class) {
4522             // If the qualified item is not a type and the selected item is static, report
4523             // a warning. Make allowance for the class of an array type e.g. Object[].class)
4524             if (!sym.owner.isAnonymous()) {
4525                 chk.warnStatic(tree, Warnings.StaticNotQualifiedByType(sym.kind.kindName(), sym.owner));
4526             } else {
4527                 chk.warnStatic(tree, Warnings.StaticNotQualifiedByType2(sym.kind.kindName()));
4528             }
4529         }
4530 
4531         // If we are selecting an instance member via a `super', ...
4532         if (env.info.selectSuper && (sym.flags() & STATIC) == 0) {
4533 
4534             // Check that super-qualified symbols are not abstract (JLS)
4535             rs.checkNonAbstract(tree.pos(), sym);
4536 
4537             if (site.isRaw()) {
4538                 // Determine argument types for site.
4539                 Type site1 = types.asSuper(env.enclClass.sym.type, site.tsym);
4540                 if (site1 != null) site = site1;
4541             }
4542         }
4543 
4544         if (env.info.isSerializable) {
4545             chk.checkAccessFromSerializableElement(tree, env.info.isSerializableLambda);
4546         }
4547 
4548         env.info.selectSuper = selectSuperPrev;
4549         result = checkId(tree, site, sym, env, resultInfo);
4550     }
4551     //where
4552         /** Determine symbol referenced by a Select expression,
4553          *
4554          *  @param tree   The select tree.
4555          *  @param site   The type of the selected expression,
4556          *  @param env    The current environment.
4557          *  @param resultInfo The current result.
4558          */
4559         private Symbol selectSym(JCFieldAccess tree,
4560                                  Symbol location,
4561                                  Type site,
4562                                  Env<AttrContext> env,
4563                                  ResultInfo resultInfo) {
4564             DiagnosticPosition pos = tree.pos();
4565             Name name = tree.name;
4566             switch (site.getTag()) {
4567             case PACKAGE:
4568                 return rs.accessBase(
4569                     rs.findIdentInPackage(pos, env, site.tsym, name, resultInfo.pkind),
4570                     pos, location, site, name, true);
4571             case ARRAY:
4572             case CLASS:
4573                 if (resultInfo.pt.hasTag(METHOD) || resultInfo.pt.hasTag(FORALL)) {
4574                     return rs.resolveQualifiedMethod(
4575                         pos, env, location, site, name, resultInfo.pt.getParameterTypes(), resultInfo.pt.getTypeArguments());
4576                 } else if (name == names._this || name == names._super) {
4577                     return rs.resolveSelf(pos, env, site.tsym, name);
4578                 } else if (name == names._class) {
4579                     // In this case, we have already made sure in
4580                     // visitSelect that qualifier expression is a type.
4581                     return syms.getClassField(site, types);
4582                 } else {
4583                     // We are seeing a plain identifier as selector.
4584                     Symbol sym = rs.findIdentInType(pos, env, site, name, resultInfo.pkind);
4585                         sym = rs.accessBase(sym, pos, location, site, name, true);
4586                     return sym;
4587                 }
4588             case WILDCARD:
4589                 throw new AssertionError(tree);
4590             case TYPEVAR:
4591                 // Normally, site.getUpperBound() shouldn't be null.
4592                 // It should only happen during memberEnter/attribBase
4593                 // when determining the supertype which *must* be
4594                 // done before attributing the type variables.  In
4595                 // other words, we are seeing this illegal program:
4596                 // class B<T> extends A<T.foo> {}
4597                 Symbol sym = (site.getUpperBound() != null)
4598                     ? selectSym(tree, location, capture(site.getUpperBound()), env, resultInfo)
4599                     : null;
4600                 if (sym == null) {
4601                     log.error(pos, Errors.TypeVarCantBeDeref);
4602                     return syms.errSymbol;
4603                 } else {
4604                     Symbol sym2 = (sym.flags() & Flags.PRIVATE) != 0 ?
4605                         rs.new AccessError(env, site, sym) :
4606                                 sym;
4607                     rs.accessBase(sym2, pos, location, site, name, true);
4608                     return sym;
4609                 }
4610             case ERROR:
4611                 // preserve identifier names through errors
4612                 return types.createErrorType(name, site.tsym, site).tsym;
4613             default:
4614                 // The qualifier expression is of a primitive type -- only
4615                 // .class is allowed for these.
4616                 if (name == names._class) {
4617                     // In this case, we have already made sure in Select that
4618                     // qualifier expression is a type.
4619                     return syms.getClassField(site, types);
4620                 } else {
4621                     log.error(pos, Errors.CantDeref(site));
4622                     return syms.errSymbol;
4623                 }
4624             }
4625         }
4626 
4627         /** Determine type of identifier or select expression and check that
4628          *  (1) the referenced symbol is not deprecated
4629          *  (2) the symbol's type is safe (@see checkSafe)
4630          *  (3) if symbol is a variable, check that its type and kind are
4631          *      compatible with the prototype and protokind.
4632          *  (4) if symbol is an instance field of a raw type,
4633          *      which is being assigned to, issue an unchecked warning if its
4634          *      type changes under erasure.
4635          *  (5) if symbol is an instance method of a raw type, issue an
4636          *      unchecked warning if its argument types change under erasure.
4637          *  If checks succeed:
4638          *    If symbol is a constant, return its constant type
4639          *    else if symbol is a method, return its result type
4640          *    otherwise return its type.
4641          *  Otherwise return errType.
4642          *
4643          *  @param tree       The syntax tree representing the identifier
4644          *  @param site       If this is a select, the type of the selected
4645          *                    expression, otherwise the type of the current class.
4646          *  @param sym        The symbol representing the identifier.
4647          *  @param env        The current environment.
4648          *  @param resultInfo    The expected result
4649          */
4650         Type checkId(JCTree tree,
4651                      Type site,
4652                      Symbol sym,
4653                      Env<AttrContext> env,
4654                      ResultInfo resultInfo) {
4655             return (resultInfo.pt.hasTag(FORALL) || resultInfo.pt.hasTag(METHOD)) ?
4656                     checkMethodIdInternal(tree, site, sym, env, resultInfo) :
4657                     checkIdInternal(tree, site, sym, resultInfo.pt, env, resultInfo);
4658         }
4659 
4660         Type checkMethodIdInternal(JCTree tree,
4661                      Type site,
4662                      Symbol sym,
4663                      Env<AttrContext> env,
4664                      ResultInfo resultInfo) {
4665             if (resultInfo.pkind.contains(KindSelector.POLY)) {
4666                 return attrRecover.recoverMethodInvocation(tree, site, sym, env, resultInfo);
4667             } else {
4668                 return checkIdInternal(tree, site, sym, resultInfo.pt, env, resultInfo);
4669             }
4670         }
4671 
4672         Type checkIdInternal(JCTree tree,
4673                      Type site,
4674                      Symbol sym,
4675                      Type pt,
4676                      Env<AttrContext> env,
4677                      ResultInfo resultInfo) {
4678             Type owntype; // The computed type of this identifier occurrence.
4679             switch (sym.kind) {
4680             case TYP:
4681                 // For types, the computed type equals the symbol's type,
4682                 // except for two situations:
4683                 owntype = sym.type;
4684                 if (owntype.hasTag(CLASS)) {
4685                     chk.checkForBadAuxiliaryClassAccess(tree.pos(), env, (ClassSymbol)sym);
4686                     Type ownOuter = owntype.getEnclosingType();
4687 
4688                     // (a) If the symbol's type is parameterized, erase it
4689                     // because no type parameters were given.
4690                     // We recover generic outer type later in visitTypeApply.
4691                     if (owntype.tsym.type.getTypeArguments().nonEmpty()) {
4692                         owntype = types.erasure(owntype);
4693                     }
4694 
4695                     // (b) If the symbol's type is an inner class, then
4696                     // we have to interpret its outer type as a superclass
4697                     // of the site type. Example:
4698                     //
4699                     // class Tree<A> { class Visitor { ... } }
4700                     // class PointTree extends Tree<Point> { ... }
4701                     // ...PointTree.Visitor...
4702                     //
4703                     // Then the type of the last expression above is
4704                     // Tree<Point>.Visitor.
4705                     else if (ownOuter.hasTag(CLASS) && site != ownOuter) {
4706                         Type normOuter = site;
4707                         if (normOuter.hasTag(CLASS)) {
4708                             normOuter = types.asEnclosingSuper(site, ownOuter.tsym);
4709                         }
4710                         if (normOuter == null) // perhaps from an import
4711                             normOuter = types.erasure(ownOuter);
4712                         if (normOuter != ownOuter)
4713                             owntype = new ClassType(
4714                                 normOuter, List.nil(), owntype.tsym,
4715                                 owntype.getMetadata());
4716                     }
4717                 }
4718                 break;
4719             case VAR:
4720                 VarSymbol v = (VarSymbol)sym;
4721 
4722                 if (env.info.enclVar != null
4723                         && v.type.hasTag(NONE)) {
4724                     //self reference to implicitly typed variable declaration
4725                     log.error(TreeInfo.positionFor(v, env.enclClass), Errors.CantInferLocalVarType(v.name, Fragments.LocalSelfRef));
4726                     return tree.type = v.type = types.createErrorType(v.type);
4727                 }
4728 
4729                 // Test (4): if symbol is an instance field of a raw type,
4730                 // which is being assigned to, issue an unchecked warning if
4731                 // its type changes under erasure.
4732                 if (KindSelector.ASG.subset(pkind()) &&
4733                     v.owner.kind == TYP &&
4734                     (v.flags() & STATIC) == 0 &&
4735                     (site.hasTag(CLASS) || site.hasTag(TYPEVAR))) {
4736                     Type s = types.asOuterSuper(site, v.owner);
4737                     if (s != null &&
4738                         s.isRaw() &&
4739                         !types.isSameType(v.type, v.erasure(types))) {
4740                         chk.warnUnchecked(tree.pos(), Warnings.UncheckedAssignToVar(v, s));
4741                     }
4742                 }
4743                 // The computed type of a variable is the type of the
4744                 // variable symbol, taken as a member of the site type.
4745                 owntype = (sym.owner.kind == TYP &&
4746                            sym.name != names._this && sym.name != names._super)
4747                     ? types.memberType(site, sym)
4748                     : sym.type;
4749 
4750                 // If the variable is a constant, record constant value in
4751                 // computed type.
4752                 if (v.getConstValue() != null && isStaticReference(tree))
4753                     owntype = owntype.constType(v.getConstValue());
4754 
4755                 if (resultInfo.pkind == KindSelector.VAL) {
4756                     owntype = capture(owntype); // capture "names as expressions"
4757                 }
4758                 break;
4759             case MTH: {
4760                 owntype = checkMethod(site, sym,
4761                         new ResultInfo(resultInfo.pkind, resultInfo.pt.getReturnType(), resultInfo.checkContext, resultInfo.checkMode),
4762                         env, TreeInfo.args(env.tree), resultInfo.pt.getParameterTypes(),
4763                         resultInfo.pt.getTypeArguments());
4764                 chk.checkRestricted(tree.pos(), sym);
4765                 break;
4766             }
4767             case PCK: case ERR:
4768                 owntype = sym.type;
4769                 break;
4770             default:
4771                 throw new AssertionError("unexpected kind: " + sym.kind +
4772                                          " in tree " + tree);
4773             }
4774 
4775             // Emit a `deprecation' warning if symbol is deprecated.
4776             // (for constructors (but not for constructor references), the error
4777             // was given when the constructor was resolved)
4778 
4779             if (sym.name != names.init || tree.hasTag(REFERENCE)) {
4780                 chk.checkDeprecated(tree.pos(), env.info.scope.owner, sym);
4781                 chk.checkSunAPI(tree.pos(), sym);
4782                 chk.checkProfile(tree.pos(), sym);
4783                 chk.checkPreview(tree.pos(), env.info.scope.owner, sym);
4784             }
4785 
4786             if (pt.isErroneous()) {
4787                 owntype = types.createErrorType(owntype);
4788             }
4789 
4790             // If symbol is a variable, check that its type and
4791             // kind are compatible with the prototype and protokind.
4792             return check(tree, owntype, sym.kind.toSelector(), resultInfo);
4793         }
4794 
4795         /** Check that variable is initialized and evaluate the variable's
4796          *  initializer, if not yet done. Also check that variable is not
4797          *  referenced before it is defined.
4798          *  @param tree    The tree making up the variable reference.
4799          *  @param env     The current environment.
4800          *  @param v       The variable's symbol.
4801          */
4802         private void checkInit(JCTree tree,
4803                                Env<AttrContext> env,
4804                                VarSymbol v,
4805                                boolean onlyWarning) {
4806             // A forward reference is diagnosed if the declaration position
4807             // of the variable is greater than the current tree position
4808             // and the tree and variable definition occur in the same class
4809             // definition.  Note that writes don't count as references.
4810             // This check applies only to class and instance
4811             // variables.  Local variables follow different scope rules,
4812             // and are subject to definite assignment checking.
4813             Env<AttrContext> initEnv = enclosingInitEnv(env);
4814             if (initEnv != null &&
4815                 (initEnv.info.enclVar == v || v.pos > tree.pos) &&
4816                 v.owner.kind == TYP &&
4817                 v.owner == env.info.scope.owner.enclClass() &&
4818                 ((v.flags() & STATIC) != 0) == Resolve.isStatic(env) &&
4819                 (!env.tree.hasTag(ASSIGN) ||
4820                  TreeInfo.skipParens(((JCAssign) env.tree).lhs) != tree)) {
4821                 if (!onlyWarning || isStaticEnumField(v)) {
4822                     Error errkey = (initEnv.info.enclVar == v) ?
4823                                 Errors.IllegalSelfRef : Errors.IllegalForwardRef;
4824                     log.error(tree.pos(), errkey);
4825                 } else if (useBeforeDeclarationWarning) {
4826                     Warning warnkey = (initEnv.info.enclVar == v) ?
4827                                 Warnings.SelfRef(v) : Warnings.ForwardRef(v);
4828                     log.warning(tree.pos(), warnkey);
4829                 }
4830             }
4831 
4832             v.getConstValue(); // ensure initializer is evaluated
4833 
4834             checkEnumInitializer(tree, env, v);
4835         }
4836 
4837         /**
4838          * Returns the enclosing init environment associated with this env (if any). An init env
4839          * can be either a field declaration env or a static/instance initializer env.
4840          */
4841         Env<AttrContext> enclosingInitEnv(Env<AttrContext> env) {
4842             while (true) {
4843                 switch (env.tree.getTag()) {
4844                     case VARDEF:
4845                         JCVariableDecl vdecl = (JCVariableDecl)env.tree;
4846                         if (vdecl.sym.owner.kind == TYP) {
4847                             //field
4848                             return env;
4849                         }
4850                         break;
4851                     case BLOCK:
4852                         if (env.next.tree.hasTag(CLASSDEF)) {
4853                             //instance/static initializer
4854                             return env;
4855                         }
4856                         break;
4857                     case METHODDEF:
4858                     case CLASSDEF:
4859                     case TOPLEVEL:
4860                         return null;
4861                 }
4862                 Assert.checkNonNull(env.next);
4863                 env = env.next;
4864             }
4865         }
4866 
4867         /**
4868          * Check for illegal references to static members of enum.  In
4869          * an enum type, constructors and initializers may not
4870          * reference its static members unless they are constant.
4871          *
4872          * @param tree    The tree making up the variable reference.
4873          * @param env     The current environment.
4874          * @param v       The variable's symbol.
4875          * @jls 8.9 Enum Types
4876          */
4877         private void checkEnumInitializer(JCTree tree, Env<AttrContext> env, VarSymbol v) {
4878             // JLS:
4879             //
4880             // "It is a compile-time error to reference a static field
4881             // of an enum type that is not a compile-time constant
4882             // (15.28) from constructors, instance initializer blocks,
4883             // or instance variable initializer expressions of that
4884             // type. It is a compile-time error for the constructors,
4885             // instance initializer blocks, or instance variable
4886             // initializer expressions of an enum constant e to refer
4887             // to itself or to an enum constant of the same type that
4888             // is declared to the right of e."
4889             if (isStaticEnumField(v)) {
4890                 ClassSymbol enclClass = env.info.scope.owner.enclClass();
4891 
4892                 if (enclClass == null || enclClass.owner == null)
4893                     return;
4894 
4895                 // See if the enclosing class is the enum (or a
4896                 // subclass thereof) declaring v.  If not, this
4897                 // reference is OK.
4898                 if (v.owner != enclClass && !types.isSubtype(enclClass.type, v.owner.type))
4899                     return;
4900 
4901                 // If the reference isn't from an initializer, then
4902                 // the reference is OK.
4903                 if (!Resolve.isInitializer(env))
4904                     return;
4905 
4906                 log.error(tree.pos(), Errors.IllegalEnumStaticRef);
4907             }
4908         }
4909 
4910         /** Is the given symbol a static, non-constant field of an Enum?
4911          *  Note: enum literals should not be regarded as such
4912          */
4913         private boolean isStaticEnumField(VarSymbol v) {
4914             return Flags.isEnum(v.owner) &&
4915                    Flags.isStatic(v) &&
4916                    !Flags.isConstant(v) &&
4917                    v.name != names._class;
4918         }
4919 
4920     /**
4921      * Check that method arguments conform to its instantiation.
4922      **/
4923     public Type checkMethod(Type site,
4924                             final Symbol sym,
4925                             ResultInfo resultInfo,
4926                             Env<AttrContext> env,
4927                             final List<JCExpression> argtrees,
4928                             List<Type> argtypes,
4929                             List<Type> typeargtypes) {
4930         // Test (5): if symbol is an instance method of a raw type, issue
4931         // an unchecked warning if its argument types change under erasure.
4932         if ((sym.flags() & STATIC) == 0 &&
4933             (site.hasTag(CLASS) || site.hasTag(TYPEVAR))) {
4934             Type s = types.asOuterSuper(site, sym.owner);
4935             if (s != null && s.isRaw() &&
4936                 !types.isSameTypes(sym.type.getParameterTypes(),
4937                                    sym.erasure(types).getParameterTypes())) {
4938                 chk.warnUnchecked(env.tree.pos(), Warnings.UncheckedCallMbrOfRawType(sym, s));
4939             }
4940         }
4941 
4942         if (env.info.defaultSuperCallSite != null) {
4943             for (Type sup : types.interfaces(env.enclClass.type).prepend(types.supertype((env.enclClass.type)))) {
4944                 if (!sup.tsym.isSubClass(sym.enclClass(), types) ||
4945                         types.isSameType(sup, env.info.defaultSuperCallSite)) continue;
4946                 List<MethodSymbol> icand_sup =
4947                         types.interfaceCandidates(sup, (MethodSymbol)sym);
4948                 if (icand_sup.nonEmpty() &&
4949                         icand_sup.head != sym &&
4950                         icand_sup.head.overrides(sym, icand_sup.head.enclClass(), types, true)) {
4951                     log.error(env.tree.pos(),
4952                               Errors.IllegalDefaultSuperCall(env.info.defaultSuperCallSite, Fragments.OverriddenDefault(sym, sup)));
4953                     break;
4954                 }
4955             }
4956             env.info.defaultSuperCallSite = null;
4957         }
4958 
4959         if (sym.isStatic() && site.isInterface() && env.tree.hasTag(APPLY)) {
4960             JCMethodInvocation app = (JCMethodInvocation)env.tree;
4961             if (app.meth.hasTag(SELECT) &&
4962                     !TreeInfo.isStaticSelector(((JCFieldAccess)app.meth).selected, names)) {
4963                 log.error(env.tree.pos(), Errors.IllegalStaticIntfMethCall(site));
4964             }
4965         }
4966 
4967         // Compute the identifier's instantiated type.
4968         // For methods, we need to compute the instance type by
4969         // Resolve.instantiate from the symbol's type as well as
4970         // any type arguments and value arguments.
4971         Warner noteWarner = new Warner();
4972         try {
4973             Type owntype = rs.checkMethod(
4974                     env,
4975                     site,
4976                     sym,
4977                     resultInfo,
4978                     argtypes,
4979                     typeargtypes,
4980                     noteWarner);
4981 
4982             DeferredAttr.DeferredTypeMap<Void> checkDeferredMap =
4983                 deferredAttr.new DeferredTypeMap<>(DeferredAttr.AttrMode.CHECK, sym, env.info.pendingResolutionPhase);
4984 
4985             argtypes = argtypes.map(checkDeferredMap);
4986 
4987             if (noteWarner.hasNonSilentLint(LintCategory.UNCHECKED)) {
4988                 chk.warnUnchecked(env.tree.pos(), Warnings.UncheckedMethInvocationApplied(kindName(sym),
4989                         sym.name,
4990                         rs.methodArguments(sym.type.getParameterTypes()),
4991                         rs.methodArguments(argtypes.map(checkDeferredMap)),
4992                         kindName(sym.location()),
4993                         sym.location()));
4994                 if (resultInfo.pt != Infer.anyPoly ||
4995                         !owntype.hasTag(METHOD) ||
4996                         !owntype.isPartial()) {
4997                     //if this is not a partially inferred method type, erase return type. Otherwise,
4998                     //erasure is carried out in PartiallyInferredMethodType.check().
4999                     owntype = new MethodType(owntype.getParameterTypes(),
5000                             types.erasure(owntype.getReturnType()),
5001                             types.erasure(owntype.getThrownTypes()),
5002                             syms.methodClass);
5003                 }
5004             }
5005 
5006             PolyKind pkind = (sym.type.hasTag(FORALL) &&
5007                  sym.type.getReturnType().containsAny(((ForAll)sym.type).tvars)) ?
5008                  PolyKind.POLY : PolyKind.STANDALONE;
5009             TreeInfo.setPolyKind(env.tree, pkind);
5010 
5011             return (resultInfo.pt == Infer.anyPoly) ?
5012                     owntype :
5013                     chk.checkMethod(owntype, sym, env, argtrees, argtypes, env.info.lastResolveVarargs(),
5014                             resultInfo.checkContext.inferenceContext());
5015         } catch (Infer.InferenceException ex) {
5016             //invalid target type - propagate exception outwards or report error
5017             //depending on the current check context
5018             resultInfo.checkContext.report(env.tree.pos(), ex.getDiagnostic());
5019             return types.createErrorType(site);
5020         } catch (Resolve.InapplicableMethodException ex) {
5021             final JCDiagnostic diag = ex.getDiagnostic();
5022             Resolve.InapplicableSymbolError errSym = rs.new InapplicableSymbolError(null) {
5023                 @Override
5024                 protected Pair<Symbol, JCDiagnostic> errCandidate() {
5025                     return new Pair<>(sym, diag);
5026                 }
5027             };
5028             List<Type> argtypes2 = argtypes.map(
5029                     rs.new ResolveDeferredRecoveryMap(AttrMode.CHECK, sym, env.info.pendingResolutionPhase));
5030             JCDiagnostic errDiag = errSym.getDiagnostic(JCDiagnostic.DiagnosticType.ERROR,
5031                     env.tree, sym, site, sym.name, argtypes2, typeargtypes);
5032             log.report(errDiag);
5033             return types.createErrorType(site);
5034         }
5035     }
5036 
5037     public void visitLiteral(JCLiteral tree) {
5038         result = check(tree, litType(tree.typetag).constType(tree.value),
5039                 KindSelector.VAL, resultInfo);
5040     }
5041     //where
5042     /** Return the type of a literal with given type tag.
5043      */
5044     Type litType(TypeTag tag) {
5045         return (tag == CLASS) ? syms.stringType : syms.typeOfTag[tag.ordinal()];
5046     }
5047 
5048     public void visitTypeIdent(JCPrimitiveTypeTree tree) {
5049         result = check(tree, syms.typeOfTag[tree.typetag.ordinal()], KindSelector.TYP, resultInfo);
5050     }
5051 
5052     public void visitTypeArray(JCArrayTypeTree tree) {
5053         Type etype = attribType(tree.elemtype, env);
5054         Type type = new ArrayType(etype, syms.arrayClass);
5055         result = check(tree, type, KindSelector.TYP, resultInfo);
5056     }
5057 
5058     /** Visitor method for parameterized types.
5059      *  Bound checking is left until later, since types are attributed
5060      *  before supertype structure is completely known
5061      */
5062     public void visitTypeApply(JCTypeApply tree) {
5063         Type owntype = types.createErrorType(tree.type);
5064 
5065         // Attribute functor part of application and make sure it's a class.
5066         Type clazztype = chk.checkClassType(tree.clazz.pos(), attribType(tree.clazz, env));
5067 
5068         // Attribute type parameters
5069         List<Type> actuals = attribTypes(tree.arguments, env);
5070 
5071         if (clazztype.hasTag(CLASS)) {
5072             List<Type> formals = clazztype.tsym.type.getTypeArguments();
5073             if (actuals.isEmpty()) //diamond
5074                 actuals = formals;
5075 
5076             if (actuals.length() == formals.length()) {
5077                 List<Type> a = actuals;
5078                 List<Type> f = formals;
5079                 while (a.nonEmpty()) {
5080                     a.head = a.head.withTypeVar(f.head);
5081                     a = a.tail;
5082                     f = f.tail;
5083                 }
5084                 // Compute the proper generic outer
5085                 Type clazzOuter = clazztype.getEnclosingType();
5086                 if (clazzOuter.hasTag(CLASS)) {
5087                     Type site;
5088                     JCExpression clazz = TreeInfo.typeIn(tree.clazz);
5089                     if (clazz.hasTag(IDENT)) {
5090                         site = env.enclClass.sym.type;
5091                     } else if (clazz.hasTag(SELECT)) {
5092                         site = ((JCFieldAccess) clazz).selected.type;
5093                     } else throw new AssertionError(""+tree);
5094                     if (clazzOuter.hasTag(CLASS) && site != clazzOuter) {
5095                         if (site.hasTag(CLASS))
5096                             site = types.asOuterSuper(site, clazzOuter.tsym);
5097                         if (site == null)
5098                             site = types.erasure(clazzOuter);
5099                         clazzOuter = site;
5100                     }
5101                 }
5102                 owntype = new ClassType(clazzOuter, actuals, clazztype.tsym,
5103                                         clazztype.getMetadata());
5104             } else {
5105                 if (formals.length() != 0) {
5106                     log.error(tree.pos(),
5107                               Errors.WrongNumberTypeArgs(Integer.toString(formals.length())));
5108                 } else {
5109                     log.error(tree.pos(), Errors.TypeDoesntTakeParams(clazztype.tsym));
5110                 }
5111                 owntype = types.createErrorType(tree.type);
5112             }
5113         }
5114         result = check(tree, owntype, KindSelector.TYP, resultInfo);
5115     }
5116 
5117     public void visitTypeUnion(JCTypeUnion tree) {
5118         ListBuffer<Type> multicatchTypes = new ListBuffer<>();
5119         ListBuffer<Type> all_multicatchTypes = null; // lazy, only if needed
5120         for (JCExpression typeTree : tree.alternatives) {
5121             Type ctype = attribType(typeTree, env);
5122             ctype = chk.checkType(typeTree.pos(),
5123                           chk.checkClassType(typeTree.pos(), ctype),
5124                           syms.throwableType);
5125             if (!ctype.isErroneous()) {
5126                 //check that alternatives of a union type are pairwise
5127                 //unrelated w.r.t. subtyping
5128                 if (chk.intersects(ctype,  multicatchTypes.toList())) {
5129                     for (Type t : multicatchTypes) {
5130                         boolean sub = types.isSubtype(ctype, t);
5131                         boolean sup = types.isSubtype(t, ctype);
5132                         if (sub || sup) {
5133                             //assume 'a' <: 'b'
5134                             Type a = sub ? ctype : t;
5135                             Type b = sub ? t : ctype;
5136                             log.error(typeTree.pos(), Errors.MulticatchTypesMustBeDisjoint(a, b));
5137                         }
5138                     }
5139                 }
5140                 multicatchTypes.append(ctype);
5141                 if (all_multicatchTypes != null)
5142                     all_multicatchTypes.append(ctype);
5143             } else {
5144                 if (all_multicatchTypes == null) {
5145                     all_multicatchTypes = new ListBuffer<>();
5146                     all_multicatchTypes.appendList(multicatchTypes);
5147                 }
5148                 all_multicatchTypes.append(ctype);
5149             }
5150         }
5151         Type t = check(tree, types.lub(multicatchTypes.toList()),
5152                 KindSelector.TYP, resultInfo.dup(CheckMode.NO_TREE_UPDATE));
5153         if (t.hasTag(CLASS)) {
5154             List<Type> alternatives =
5155                 ((all_multicatchTypes == null) ? multicatchTypes : all_multicatchTypes).toList();
5156             t = new UnionClassType((ClassType) t, alternatives);
5157         }
5158         tree.type = result = t;
5159     }
5160 
5161     public void visitTypeIntersection(JCTypeIntersection tree) {
5162         attribTypes(tree.bounds, env);
5163         tree.type = result = checkIntersection(tree, tree.bounds);
5164     }
5165 
5166     public void visitTypeParameter(JCTypeParameter tree) {
5167         TypeVar typeVar = (TypeVar) tree.type;
5168 
5169         if (tree.annotations != null && tree.annotations.nonEmpty()) {
5170             annotate.annotateTypeParameterSecondStage(tree, tree.annotations);
5171         }
5172 
5173         if (!typeVar.getUpperBound().isErroneous()) {
5174             //fixup type-parameter bound computed in 'attribTypeVariables'
5175             typeVar.setUpperBound(checkIntersection(tree, tree.bounds));
5176         }
5177     }
5178 
5179     Type checkIntersection(JCTree tree, List<JCExpression> bounds) {
5180         Set<Symbol> boundSet = new HashSet<>();
5181         if (bounds.nonEmpty()) {
5182             // accept class or interface or typevar as first bound.
5183             bounds.head.type = checkBase(bounds.head.type, bounds.head, env, false, false, false);
5184             boundSet.add(types.erasure(bounds.head.type).tsym);
5185             if (bounds.head.type.isErroneous()) {
5186                 return bounds.head.type;
5187             }
5188             else if (bounds.head.type.hasTag(TYPEVAR)) {
5189                 // if first bound was a typevar, do not accept further bounds.
5190                 if (bounds.tail.nonEmpty()) {
5191                     log.error(bounds.tail.head.pos(),
5192                               Errors.TypeVarMayNotBeFollowedByOtherBounds);
5193                     return bounds.head.type;
5194                 }
5195             } else {
5196                 // if first bound was a class or interface, accept only interfaces
5197                 // as further bounds.
5198                 for (JCExpression bound : bounds.tail) {
5199                     bound.type = checkBase(bound.type, bound, env, false, true, false);
5200                     if (bound.type.isErroneous()) {
5201                         bounds = List.of(bound);
5202                     }
5203                     else if (bound.type.hasTag(CLASS)) {
5204                         chk.checkNotRepeated(bound.pos(), types.erasure(bound.type), boundSet);
5205                     }
5206                 }
5207             }
5208         }
5209 
5210         if (bounds.length() == 0) {
5211             return syms.objectType;
5212         } else if (bounds.length() == 1) {
5213             return bounds.head.type;
5214         } else {
5215             Type owntype = types.makeIntersectionType(TreeInfo.types(bounds));
5216             // ... the variable's bound is a class type flagged COMPOUND
5217             // (see comment for TypeVar.bound).
5218             // In this case, generate a class tree that represents the
5219             // bound class, ...
5220             JCExpression extending;
5221             List<JCExpression> implementing;
5222             if (!bounds.head.type.isInterface()) {
5223                 extending = bounds.head;
5224                 implementing = bounds.tail;
5225             } else {
5226                 extending = null;
5227                 implementing = bounds;
5228             }
5229             JCClassDecl cd = make.at(tree).ClassDef(
5230                 make.Modifiers(PUBLIC | ABSTRACT),
5231                 names.empty, List.nil(),
5232                 extending, implementing, List.nil());
5233 
5234             ClassSymbol c = (ClassSymbol)owntype.tsym;
5235             Assert.check((c.flags() & COMPOUND) != 0);
5236             cd.sym = c;
5237             c.sourcefile = env.toplevel.sourcefile;
5238 
5239             // ... and attribute the bound class
5240             c.flags_field |= UNATTRIBUTED;
5241             Env<AttrContext> cenv = enter.classEnv(cd, env);
5242             typeEnvs.put(c, cenv);
5243             attribClass(c);
5244             return owntype;
5245         }
5246     }
5247 
5248     public void visitWildcard(JCWildcard tree) {
5249         //- System.err.println("visitWildcard("+tree+");");//DEBUG
5250         Type type = (tree.kind.kind == BoundKind.UNBOUND)
5251             ? syms.objectType
5252             : attribType(tree.inner, env);
5253         result = check(tree, new WildcardType(chk.checkRefType(tree.pos(), type),
5254                                               tree.kind.kind,
5255                                               syms.boundClass),
5256                 KindSelector.TYP, resultInfo);
5257     }
5258 
5259     public void visitAnnotation(JCAnnotation tree) {
5260         Assert.error("should be handled in annotate");
5261     }
5262 
5263     @Override
5264     public void visitModifiers(JCModifiers tree) {
5265         //error recovery only:
5266         Assert.check(resultInfo.pkind == KindSelector.ERR);
5267 
5268         attribAnnotationTypes(tree.annotations, env);
5269     }
5270 
5271     public void visitAnnotatedType(JCAnnotatedType tree) {
5272         attribAnnotationTypes(tree.annotations, env);
5273         Type underlyingType =
5274                 attribTree(tree.underlyingType, env, new ResultInfo(KindSelector.TYP_PCK, Type.noType));
5275         if (underlyingType.hasTag(PACKAGE)) {
5276             // Type annotations are not admissible on packages, but we handle packages here to
5277             // report better diagnostics later in validateAnnotatedType.
5278             result = tree.type = underlyingType;
5279             return;
5280         }
5281         Type annotatedType = underlyingType.preannotatedType();
5282 
5283         if (!env.info.isNewClass)
5284             annotate.annotateTypeSecondStage(tree, tree.annotations, annotatedType);
5285         result = tree.type = annotatedType;
5286     }
5287 
5288     public void visitErroneous(JCErroneous tree) {
5289         if (tree.errs != null) {
5290             Env<AttrContext> errEnv = env.dup(env.tree, env.info.dup());
5291             errEnv.info.returnResult = unknownExprInfo;
5292             for (JCTree err : tree.errs)
5293                 attribTree(err, errEnv, new ResultInfo(KindSelector.ERR, pt()));
5294         }
5295         result = tree.type = syms.errType;
5296     }
5297 
5298     /** Default visitor method for all other trees.
5299      */
5300     public void visitTree(JCTree tree) {
5301         throw new AssertionError();
5302     }
5303 
5304     /**
5305      * Attribute an env for either a top level tree or class or module declaration.
5306      */
5307     public void attrib(Env<AttrContext> env) {
5308         switch (env.tree.getTag()) {
5309             case MODULEDEF:
5310                 attribModule(env.tree.pos(), ((JCModuleDecl)env.tree).sym);
5311                 break;
5312             case PACKAGEDEF:
5313                 attribPackage(env.tree.pos(), ((JCPackageDecl) env.tree).packge);
5314                 break;
5315             default:
5316                 attribClass(env.tree.pos(), env.enclClass.sym);
5317         }
5318 
5319         annotate.flush();
5320     }
5321 
5322     public void attribPackage(DiagnosticPosition pos, PackageSymbol p) {
5323         try {
5324             annotate.flush();
5325             attribPackage(p);
5326         } catch (CompletionFailure ex) {
5327             chk.completionError(pos, ex);
5328         }
5329     }
5330 
5331     void attribPackage(PackageSymbol p) {
5332         attribWithLint(p,
5333                        env -> chk.checkDeprecatedAnnotation(((JCPackageDecl) env.tree).pid.pos(), p));
5334     }
5335 
5336     public void attribModule(DiagnosticPosition pos, ModuleSymbol m) {
5337         try {
5338             annotate.flush();
5339             attribModule(m);
5340         } catch (CompletionFailure ex) {
5341             chk.completionError(pos, ex);
5342         }
5343     }
5344 
5345     void attribModule(ModuleSymbol m) {
5346         attribWithLint(m, env -> attribStat(env.tree, env));
5347     }
5348 
5349     private void attribWithLint(TypeSymbol sym, Consumer<Env<AttrContext>> attrib) {
5350         Env<AttrContext> env = typeEnvs.get(sym);
5351 
5352         Env<AttrContext> lintEnv = env;
5353         while (lintEnv.info.lint == null)
5354             lintEnv = lintEnv.next;
5355 
5356         Lint lint = lintEnv.info.lint.augment(sym);
5357 
5358         Lint prevLint = chk.setLint(lint);
5359         JavaFileObject prev = log.useSource(env.toplevel.sourcefile);
5360 
5361         try {
5362             deferredLintHandler.flush(env.tree.pos(), lint);
5363             attrib.accept(env);
5364         } finally {
5365             log.useSource(prev);
5366             chk.setLint(prevLint);
5367         }
5368     }
5369 
5370     /** Main method: attribute class definition associated with given class symbol.
5371      *  reporting completion failures at the given position.
5372      *  @param pos The source position at which completion errors are to be
5373      *             reported.
5374      *  @param c   The class symbol whose definition will be attributed.
5375      */
5376     public void attribClass(DiagnosticPosition pos, ClassSymbol c) {
5377         try {
5378             annotate.flush();
5379             attribClass(c);
5380         } catch (CompletionFailure ex) {
5381             chk.completionError(pos, ex);
5382         }
5383     }
5384 
5385     /** Attribute class definition associated with given class symbol.
5386      *  @param c   The class symbol whose definition will be attributed.
5387      */
5388     void attribClass(ClassSymbol c) throws CompletionFailure {
5389         if (c.type.hasTag(ERROR)) return;
5390 
5391         // Check for cycles in the inheritance graph, which can arise from
5392         // ill-formed class files.
5393         chk.checkNonCyclic(null, c.type);
5394 
5395         Type st = types.supertype(c.type);
5396         if ((c.flags_field & Flags.COMPOUND) == 0 &&
5397             (c.flags_field & Flags.SUPER_OWNER_ATTRIBUTED) == 0) {
5398             // First, attribute superclass.
5399             if (st.hasTag(CLASS))
5400                 attribClass((ClassSymbol)st.tsym);
5401 
5402             // Next attribute owner, if it is a class.
5403             if (c.owner.kind == TYP && c.owner.type.hasTag(CLASS))
5404                 attribClass((ClassSymbol)c.owner);
5405 
5406             c.flags_field |= Flags.SUPER_OWNER_ATTRIBUTED;
5407         }
5408 
5409         // The previous operations might have attributed the current class
5410         // if there was a cycle. So we test first whether the class is still
5411         // UNATTRIBUTED.
5412         if ((c.flags_field & UNATTRIBUTED) != 0) {
5413             c.flags_field &= ~UNATTRIBUTED;
5414 
5415             // Get environment current at the point of class definition.
5416             Env<AttrContext> env = typeEnvs.get(c);
5417 
5418             // The info.lint field in the envs stored in typeEnvs is deliberately uninitialized,
5419             // because the annotations were not available at the time the env was created. Therefore,
5420             // we look up the environment chain for the first enclosing environment for which the
5421             // lint value is set. Typically, this is the parent env, but might be further if there
5422             // are any envs created as a result of TypeParameter nodes.
5423             Env<AttrContext> lintEnv = env;
5424             while (lintEnv.info.lint == null)
5425                 lintEnv = lintEnv.next;
5426 
5427             // Having found the enclosing lint value, we can initialize the lint value for this class
5428             env.info.lint = lintEnv.info.lint.augment(c);
5429 
5430             Lint prevLint = chk.setLint(env.info.lint);
5431             JavaFileObject prev = log.useSource(c.sourcefile);
5432             ResultInfo prevReturnRes = env.info.returnResult;
5433 
5434             try {
5435                 if (c.isSealed() &&
5436                         !c.isEnum() &&
5437                         !c.isPermittedExplicit &&
5438                         c.getPermittedSubclasses().isEmpty()) {
5439                     log.error(TreeInfo.diagnosticPositionFor(c, env.tree), Errors.SealedClassMustHaveSubclasses);
5440                 }
5441 
5442                 if (c.isSealed()) {
5443                     Set<Symbol> permittedTypes = new HashSet<>();
5444                     boolean sealedInUnnamed = c.packge().modle == syms.unnamedModule || c.packge().modle == syms.noModule;
5445                     for (Type subType : c.getPermittedSubclasses()) {
5446                         boolean isTypeVar = false;
5447                         if (subType.getTag() == TYPEVAR) {
5448                             isTypeVar = true; //error recovery
5449                             log.error(TreeInfo.diagnosticPositionFor(subType.tsym, env.tree),
5450                                     Errors.InvalidPermitsClause(Fragments.IsATypeVariable(subType)));
5451                         }
5452                         if (subType.tsym.isAnonymous() && !c.isEnum()) {
5453                             log.error(TreeInfo.diagnosticPositionFor(subType.tsym, env.tree),  Errors.LocalClassesCantExtendSealed(Fragments.Anonymous));
5454                         }
5455                         if (permittedTypes.contains(subType.tsym)) {
5456                             DiagnosticPosition pos =
5457                                     env.enclClass.permitting.stream()
5458                                             .filter(permittedExpr -> TreeInfo.diagnosticPositionFor(subType.tsym, permittedExpr, true) != null)
5459                                             .limit(2).collect(List.collector()).get(1);
5460                             log.error(pos, Errors.InvalidPermitsClause(Fragments.IsDuplicated(subType)));
5461                         } else {
5462                             permittedTypes.add(subType.tsym);
5463                         }
5464                         if (sealedInUnnamed) {
5465                             if (subType.tsym.packge() != c.packge()) {
5466                                 log.error(TreeInfo.diagnosticPositionFor(subType.tsym, env.tree),
5467                                         Errors.ClassInUnnamedModuleCantExtendSealedInDiffPackage(c)
5468                                 );
5469                             }
5470                         } else if (subType.tsym.packge().modle != c.packge().modle) {
5471                             log.error(TreeInfo.diagnosticPositionFor(subType.tsym, env.tree),
5472                                     Errors.ClassInModuleCantExtendSealedInDiffModule(c, c.packge().modle)
5473                             );
5474                         }
5475                         if (subType.tsym == c.type.tsym || types.isSuperType(subType, c.type)) {
5476                             log.error(TreeInfo.diagnosticPositionFor(subType.tsym, ((JCClassDecl)env.tree).permitting),
5477                                     Errors.InvalidPermitsClause(
5478                                             subType.tsym == c.type.tsym ?
5479                                                     Fragments.MustNotBeSameClass :
5480                                                     Fragments.MustNotBeSupertype(subType)
5481                                     )
5482                             );
5483                         } else if (!isTypeVar) {
5484                             boolean thisIsASuper = types.directSupertypes(subType)
5485                                                         .stream()
5486                                                         .anyMatch(d -> d.tsym == c);
5487                             if (!thisIsASuper) {
5488                                 log.error(TreeInfo.diagnosticPositionFor(subType.tsym, env.tree),
5489                                         Errors.InvalidPermitsClause(Fragments.DoesntExtendSealed(subType)));
5490                             }
5491                         }
5492                     }
5493                 }
5494 
5495                 List<ClassSymbol> sealedSupers = types.directSupertypes(c.type)
5496                                                       .stream()
5497                                                       .filter(s -> s.tsym.isSealed())
5498                                                       .map(s -> (ClassSymbol) s.tsym)
5499                                                       .collect(List.collector());
5500 
5501                 if (sealedSupers.isEmpty()) {
5502                     if ((c.flags_field & Flags.NON_SEALED) != 0) {
5503                         boolean hasErrorSuper = false;
5504 
5505                         hasErrorSuper |= types.directSupertypes(c.type)
5506                                               .stream()
5507                                               .anyMatch(s -> s.tsym.kind == Kind.ERR);
5508 
5509                         ClassType ct = (ClassType) c.type;
5510 
5511                         hasErrorSuper |= !ct.isCompound() && ct.interfaces_field != ct.all_interfaces_field;
5512 
5513                         if (!hasErrorSuper) {
5514                             log.error(TreeInfo.diagnosticPositionFor(c, env.tree), Errors.NonSealedWithNoSealedSupertype(c));
5515                         }
5516                     }
5517                 } else if ((c.flags_field & Flags.COMPOUND) == 0) {
5518                     if (c.isDirectlyOrIndirectlyLocal() && !c.isEnum()) {
5519                         log.error(TreeInfo.diagnosticPositionFor(c, env.tree), Errors.LocalClassesCantExtendSealed(c.isAnonymous() ? Fragments.Anonymous : Fragments.Local));
5520                     }
5521 
5522                     if (!c.type.isCompound()) {
5523                         for (ClassSymbol supertypeSym : sealedSupers) {
5524                             if (!supertypeSym.isPermittedSubclass(c.type.tsym)) {
5525                                 log.error(TreeInfo.diagnosticPositionFor(c.type.tsym, env.tree), Errors.CantInheritFromSealed(supertypeSym));
5526                             }
5527                         }
5528                         if (!c.isNonSealed() && !c.isFinal() && !c.isSealed()) {
5529                             log.error(TreeInfo.diagnosticPositionFor(c, env.tree),
5530                                     c.isInterface() ?
5531                                             Errors.NonSealedOrSealedExpected :
5532                                             Errors.NonSealedSealedOrFinalExpected);
5533                         }
5534                     }
5535                 }
5536 
5537                 deferredLintHandler.flush(env.tree, env.info.lint);
5538                 env.info.returnResult = null;
5539                 // java.lang.Enum may not be subclassed by a non-enum
5540                 if (st.tsym == syms.enumSym &&
5541                     ((c.flags_field & (Flags.ENUM|Flags.COMPOUND)) == 0))
5542                     log.error(env.tree.pos(), Errors.EnumNoSubclassing);
5543 
5544                 // Enums may not be extended by source-level classes
5545                 if (st.tsym != null &&
5546                     ((st.tsym.flags_field & Flags.ENUM) != 0) &&
5547                     ((c.flags_field & (Flags.ENUM | Flags.COMPOUND)) == 0)) {
5548                     log.error(env.tree.pos(), Errors.EnumTypesNotExtensible);
5549                 }
5550 
5551                 if (rs.isSerializable(c.type)) {
5552                     env.info.isSerializable = true;
5553                 }
5554 
5555                 if (c.isValueClass()) {
5556                     Assert.check(env.tree.hasTag(CLASSDEF));
5557                     chk.checkConstraintsOfValueClass((JCClassDecl) env.tree, c);
5558                 }
5559 
5560                 attribClassBody(env, c);
5561 
5562                 chk.checkDeprecatedAnnotation(env.tree.pos(), c);
5563                 chk.checkClassOverrideEqualsAndHashIfNeeded(env.tree.pos(), c);
5564                 chk.checkFunctionalInterface((JCClassDecl) env.tree, c);
5565                 chk.checkLeaksNotAccessible(env, (JCClassDecl) env.tree);
5566 
5567                 if (c.isImplicit()) {
5568                     chk.checkHasMain(env.tree.pos(), c);
5569                 }
5570             } finally {
5571                 env.info.returnResult = prevReturnRes;
5572                 log.useSource(prev);
5573                 chk.setLint(prevLint);
5574             }
5575 
5576         }
5577     }
5578 
5579     public void visitImport(JCImport tree) {
5580         // nothing to do
5581     }
5582 
5583     public void visitModuleDef(JCModuleDecl tree) {
5584         tree.sym.completeUsesProvides();
5585         ModuleSymbol msym = tree.sym;
5586         Lint lint = env.outer.info.lint = env.outer.info.lint.augment(msym);
5587         Lint prevLint = chk.setLint(lint);
5588         chk.checkModuleName(tree);
5589         chk.checkDeprecatedAnnotation(tree, msym);
5590 
5591         try {
5592             deferredLintHandler.flush(tree.pos(), lint);
5593         } finally {
5594             chk.setLint(prevLint);
5595         }
5596     }
5597 
5598     /** Finish the attribution of a class. */
5599     private void attribClassBody(Env<AttrContext> env, ClassSymbol c) {
5600         JCClassDecl tree = (JCClassDecl)env.tree;
5601         Assert.check(c == tree.sym);
5602 
5603         // Validate type parameters, supertype and interfaces.
5604         attribStats(tree.typarams, env);
5605         if (!c.isAnonymous()) {
5606             //already checked if anonymous
5607             chk.validate(tree.typarams, env);
5608             chk.validate(tree.extending, env);
5609             chk.validate(tree.implementing, env);
5610         }
5611 
5612         c.markAbstractIfNeeded(types);
5613 
5614         // If this is a non-abstract class, check that it has no abstract
5615         // methods or unimplemented methods of an implemented interface.
5616         if ((c.flags() & (ABSTRACT | INTERFACE)) == 0) {
5617             chk.checkAllDefined(tree.pos(), c);
5618         }
5619 
5620         if ((c.flags() & ANNOTATION) != 0) {
5621             if (tree.implementing.nonEmpty())
5622                 log.error(tree.implementing.head.pos(),
5623                           Errors.CantExtendIntfAnnotation);
5624             if (tree.typarams.nonEmpty()) {
5625                 log.error(tree.typarams.head.pos(),
5626                           Errors.IntfAnnotationCantHaveTypeParams(c));
5627             }
5628 
5629             // If this annotation type has a @Repeatable, validate
5630             Attribute.Compound repeatable = c.getAnnotationTypeMetadata().getRepeatable();
5631             // If this annotation type has a @Repeatable, validate
5632             if (repeatable != null) {
5633                 // get diagnostic position for error reporting
5634                 DiagnosticPosition cbPos = getDiagnosticPosition(tree, repeatable.type);
5635                 Assert.checkNonNull(cbPos);
5636 
5637                 chk.validateRepeatable(c, repeatable, cbPos);
5638             }
5639         } else {
5640             // Check that all extended classes and interfaces
5641             // are compatible (i.e. no two define methods with same arguments
5642             // yet different return types).  (JLS 8.4.8.3)
5643             chk.checkCompatibleSupertypes(tree.pos(), c.type);
5644             chk.checkDefaultMethodClashes(tree.pos(), c.type);
5645             chk.checkPotentiallyAmbiguousOverloads(tree, c.type);
5646         }
5647 
5648         // Check that class does not import the same parameterized interface
5649         // with two different argument lists.
5650         chk.checkClassBounds(tree.pos(), c.type);
5651 
5652         tree.type = c.type;
5653 
5654         for (List<JCTypeParameter> l = tree.typarams;
5655              l.nonEmpty(); l = l.tail) {
5656              Assert.checkNonNull(env.info.scope.findFirst(l.head.name));
5657         }
5658 
5659         // Check that a generic class doesn't extend Throwable
5660         if (!c.type.allparams().isEmpty() && types.isSubtype(c.type, syms.throwableType))
5661             log.error(tree.extending.pos(), Errors.GenericThrowable);
5662 
5663         // Check that all methods which implement some
5664         // method conform to the method they implement.
5665         chk.checkImplementations(tree);
5666 
5667         //check that a resource implementing AutoCloseable cannot throw InterruptedException
5668         checkAutoCloseable(tree.pos(), env, c.type);
5669 
5670         for (List<JCTree> l = tree.defs; l.nonEmpty(); l = l.tail) {
5671             // Attribute declaration
5672             attribStat(l.head, env);
5673             // Check that declarations in inner classes are not static (JLS 8.1.2)
5674             // Make an exception for static constants.
5675             if (!allowRecords &&
5676                     c.owner.kind != PCK &&
5677                     ((c.flags() & STATIC) == 0 || c.name == names.empty) &&
5678                     (TreeInfo.flags(l.head) & (STATIC | INTERFACE)) != 0) {
5679                 VarSymbol sym = null;
5680                 if (l.head.hasTag(VARDEF)) sym = ((JCVariableDecl) l.head).sym;
5681                 if (sym == null ||
5682                         sym.kind != VAR ||
5683                         sym.getConstValue() == null)
5684                     log.error(l.head.pos(), Errors.IclsCantHaveStaticDecl(c));
5685             }
5686         }
5687 
5688         // Check for proper placement of super()/this() calls.
5689         chk.checkSuperInitCalls(tree);
5690 
5691         // Check for cycles among non-initial constructors.
5692         chk.checkCyclicConstructors(tree);
5693 
5694         // Check for cycles among annotation elements.
5695         chk.checkNonCyclicElements(tree);
5696 
5697         // Check for proper use of serialVersionUID and other
5698         // serialization-related fields and methods
5699         if (env.info.lint.isEnabled(LintCategory.SERIAL)
5700                 && rs.isSerializable(c.type)
5701                 && !c.isAnonymous()) {
5702             chk.checkSerialStructure(env, tree, c);
5703         }
5704         // Correctly organize the positions of the type annotations
5705         typeAnnotations.organizeTypeAnnotationsBodies(tree);
5706 
5707         // Check type annotations applicability rules
5708         validateTypeAnnotations(tree, false);
5709     }
5710         // where
5711         /** get a diagnostic position for an attribute of Type t, or null if attribute missing */
5712         private DiagnosticPosition getDiagnosticPosition(JCClassDecl tree, Type t) {
5713             for(List<JCAnnotation> al = tree.mods.annotations; !al.isEmpty(); al = al.tail) {
5714                 if (types.isSameType(al.head.annotationType.type, t))
5715                     return al.head.pos();
5716             }
5717 
5718             return null;
5719         }
5720 
5721     private Type capture(Type type) {
5722         return types.capture(type);
5723     }
5724 
5725     private void setSyntheticVariableType(JCVariableDecl tree, Type type) {
5726         if (type.isErroneous()) {
5727             tree.vartype = make.at(Position.NOPOS).Erroneous();
5728         } else {
5729             tree.vartype = make.at(Position.NOPOS).Type(type);
5730         }
5731     }
5732 
5733     public void validateTypeAnnotations(JCTree tree, boolean sigOnly) {
5734         tree.accept(new TypeAnnotationsValidator(sigOnly));
5735     }
5736     //where
5737     private final class TypeAnnotationsValidator extends TreeScanner {
5738 
5739         private final boolean sigOnly;
5740         public TypeAnnotationsValidator(boolean sigOnly) {
5741             this.sigOnly = sigOnly;
5742         }
5743 
5744         public void visitAnnotation(JCAnnotation tree) {
5745             chk.validateTypeAnnotation(tree, null, false);
5746             super.visitAnnotation(tree);
5747         }
5748         public void visitAnnotatedType(JCAnnotatedType tree) {
5749             if (!tree.underlyingType.type.isErroneous()) {
5750                 super.visitAnnotatedType(tree);
5751             }
5752         }
5753         public void visitTypeParameter(JCTypeParameter tree) {
5754             chk.validateTypeAnnotations(tree.annotations, tree.type.tsym, true);
5755             scan(tree.bounds);
5756             // Don't call super.
5757             // This is needed because above we call validateTypeAnnotation with
5758             // false, which would forbid annotations on type parameters.
5759             // super.visitTypeParameter(tree);
5760         }
5761         public void visitMethodDef(JCMethodDecl tree) {
5762             if (tree.recvparam != null &&
5763                     !tree.recvparam.vartype.type.isErroneous()) {
5764                 checkForDeclarationAnnotations(tree.recvparam.mods.annotations, tree.recvparam.sym);
5765             }
5766             if (tree.restype != null && tree.restype.type != null) {
5767                 validateAnnotatedType(tree.restype, tree.restype.type);
5768             }
5769             if (sigOnly) {
5770                 scan(tree.mods);
5771                 scan(tree.restype);
5772                 scan(tree.typarams);
5773                 scan(tree.recvparam);
5774                 scan(tree.params);
5775                 scan(tree.thrown);
5776             } else {
5777                 scan(tree.defaultValue);
5778                 scan(tree.body);
5779             }
5780         }
5781         public void visitVarDef(final JCVariableDecl tree) {
5782             //System.err.println("validateTypeAnnotations.visitVarDef " + tree);
5783             if (tree.sym != null && tree.sym.type != null && !tree.isImplicitlyTyped())
5784                 validateAnnotatedType(tree.vartype, tree.sym.type);
5785             scan(tree.mods);
5786             scan(tree.vartype);
5787             if (!sigOnly) {
5788                 scan(tree.init);
5789             }
5790         }
5791         public void visitTypeCast(JCTypeCast tree) {
5792             if (tree.clazz != null && tree.clazz.type != null)
5793                 validateAnnotatedType(tree.clazz, tree.clazz.type);
5794             super.visitTypeCast(tree);
5795         }
5796         public void visitTypeTest(JCInstanceOf tree) {
5797             if (tree.pattern != null && !(tree.pattern instanceof JCPattern) && tree.pattern.type != null)
5798                 validateAnnotatedType(tree.pattern, tree.pattern.type);
5799             super.visitTypeTest(tree);
5800         }
5801         public void visitNewClass(JCNewClass tree) {
5802             if (tree.clazz != null && tree.clazz.type != null) {
5803                 if (tree.clazz.hasTag(ANNOTATED_TYPE)) {
5804                     checkForDeclarationAnnotations(((JCAnnotatedType) tree.clazz).annotations,
5805                             tree.clazz.type.tsym);
5806                 }
5807                 if (tree.def != null) {
5808                     checkForDeclarationAnnotations(tree.def.mods.annotations, tree.clazz.type.tsym);
5809                 }
5810 
5811                 validateAnnotatedType(tree.clazz, tree.clazz.type);
5812             }
5813             super.visitNewClass(tree);
5814         }
5815         public void visitNewArray(JCNewArray tree) {
5816             if (tree.elemtype != null && tree.elemtype.type != null) {
5817                 if (tree.elemtype.hasTag(ANNOTATED_TYPE)) {
5818                     checkForDeclarationAnnotations(((JCAnnotatedType) tree.elemtype).annotations,
5819                             tree.elemtype.type.tsym);
5820                 }
5821                 validateAnnotatedType(tree.elemtype, tree.elemtype.type);
5822             }
5823             super.visitNewArray(tree);
5824         }
5825         public void visitClassDef(JCClassDecl tree) {
5826             //System.err.println("validateTypeAnnotations.visitClassDef " + tree);
5827             if (sigOnly) {
5828                 scan(tree.mods);
5829                 scan(tree.typarams);
5830                 scan(tree.extending);
5831                 scan(tree.implementing);
5832             }
5833             for (JCTree member : tree.defs) {
5834                 if (member.hasTag(Tag.CLASSDEF)) {
5835                     continue;
5836                 }
5837                 scan(member);
5838             }
5839         }
5840         public void visitBlock(JCBlock tree) {
5841             if (!sigOnly) {
5842                 scan(tree.stats);
5843             }
5844         }
5845 
5846         /* I would want to model this after
5847          * com.sun.tools.javac.comp.Check.Validator.visitSelectInternal(JCFieldAccess)
5848          * and override visitSelect and visitTypeApply.
5849          * However, we only set the annotated type in the top-level type
5850          * of the symbol.
5851          * Therefore, we need to override each individual location where a type
5852          * can occur.
5853          */
5854         private void validateAnnotatedType(final JCTree errtree, final Type type) {
5855             //System.err.println("Attr.validateAnnotatedType: " + errtree + " type: " + type);
5856 
5857             if (type.isPrimitiveOrVoid()) {
5858                 return;
5859             }
5860 
5861             JCTree enclTr = errtree;
5862             Type enclTy = type;
5863 
5864             boolean repeat = true;
5865             while (repeat) {
5866                 if (enclTr.hasTag(TYPEAPPLY)) {
5867                     List<Type> tyargs = enclTy.getTypeArguments();
5868                     List<JCExpression> trargs = ((JCTypeApply)enclTr).getTypeArguments();
5869                     if (trargs.length() > 0) {
5870                         // Nothing to do for diamonds
5871                         if (tyargs.length() == trargs.length()) {
5872                             for (int i = 0; i < tyargs.length(); ++i) {
5873                                 validateAnnotatedType(trargs.get(i), tyargs.get(i));
5874                             }
5875                         }
5876                         // If the lengths don't match, it's either a diamond
5877                         // or some nested type that redundantly provides
5878                         // type arguments in the tree.
5879                     }
5880 
5881                     // Look at the clazz part of a generic type
5882                     enclTr = ((JCTree.JCTypeApply)enclTr).clazz;
5883                 }
5884 
5885                 if (enclTr.hasTag(SELECT)) {
5886                     enclTr = ((JCTree.JCFieldAccess)enclTr).getExpression();
5887                     if (enclTy != null &&
5888                             !enclTy.hasTag(NONE)) {
5889                         enclTy = enclTy.getEnclosingType();
5890                     }
5891                 } else if (enclTr.hasTag(ANNOTATED_TYPE)) {
5892                     JCAnnotatedType at = (JCTree.JCAnnotatedType) enclTr;
5893                     if (enclTy == null || enclTy.hasTag(NONE)) {
5894                         ListBuffer<Attribute.TypeCompound> onlyTypeAnnotationsBuf = new ListBuffer<>();
5895                         for (JCAnnotation an : at.getAnnotations()) {
5896                             if (chk.isTypeAnnotation(an, false)) {
5897                                 onlyTypeAnnotationsBuf.add((Attribute.TypeCompound) an.attribute);
5898                             }
5899                         }
5900                         List<Attribute.TypeCompound> onlyTypeAnnotations = onlyTypeAnnotationsBuf.toList();
5901                         if (!onlyTypeAnnotations.isEmpty()) {
5902                             Fragment annotationFragment = onlyTypeAnnotations.size() == 1 ?
5903                                     Fragments.TypeAnnotation1(onlyTypeAnnotations.head) :
5904                                     Fragments.TypeAnnotation(onlyTypeAnnotations);
5905                             JCDiagnostic.AnnotatedType annotatedType = new JCDiagnostic.AnnotatedType(
5906                                     type.stripMetadata().annotatedType(onlyTypeAnnotations));
5907                             log.error(at.underlyingType.pos(), Errors.TypeAnnotationInadmissible(annotationFragment,
5908                                     type.tsym.owner, annotatedType));
5909                         }
5910                         repeat = false;
5911                     }
5912                     enclTr = at.underlyingType;
5913                     // enclTy doesn't need to be changed
5914                 } else if (enclTr.hasTag(IDENT)) {
5915                     repeat = false;
5916                 } else if (enclTr.hasTag(JCTree.Tag.WILDCARD)) {
5917                     JCWildcard wc = (JCWildcard) enclTr;
5918                     if (wc.getKind() == JCTree.Kind.EXTENDS_WILDCARD ||
5919                             wc.getKind() == JCTree.Kind.SUPER_WILDCARD) {
5920                         validateAnnotatedType(wc.getBound(), wc.getBound().type);
5921                     } else {
5922                         // Nothing to do for UNBOUND
5923                     }
5924                     repeat = false;
5925                 } else if (enclTr.hasTag(TYPEARRAY)) {
5926                     JCArrayTypeTree art = (JCArrayTypeTree) enclTr;
5927                     validateAnnotatedType(art.getType(), art.elemtype.type);
5928                     repeat = false;
5929                 } else if (enclTr.hasTag(TYPEUNION)) {
5930                     JCTypeUnion ut = (JCTypeUnion) enclTr;
5931                     for (JCTree t : ut.getTypeAlternatives()) {
5932                         validateAnnotatedType(t, t.type);
5933                     }
5934                     repeat = false;
5935                 } else if (enclTr.hasTag(TYPEINTERSECTION)) {
5936                     JCTypeIntersection it = (JCTypeIntersection) enclTr;
5937                     for (JCTree t : it.getBounds()) {
5938                         validateAnnotatedType(t, t.type);
5939                     }
5940                     repeat = false;
5941                 } else if (enclTr.getKind() == JCTree.Kind.PRIMITIVE_TYPE ||
5942                            enclTr.getKind() == JCTree.Kind.ERRONEOUS) {
5943                     repeat = false;
5944                 } else {
5945                     Assert.error("Unexpected tree: " + enclTr + " with kind: " + enclTr.getKind() +
5946                             " within: "+ errtree + " with kind: " + errtree.getKind());
5947                 }
5948             }
5949         }
5950 
5951         private void checkForDeclarationAnnotations(List<? extends JCAnnotation> annotations,
5952                 Symbol sym) {
5953             // Ensure that no declaration annotations are present.
5954             // Note that a tree type might be an AnnotatedType with
5955             // empty annotations, if only declaration annotations were given.
5956             // This method will raise an error for such a type.
5957             for (JCAnnotation ai : annotations) {
5958                 if (!ai.type.isErroneous() &&
5959                         typeAnnotations.annotationTargetType(ai, ai.attribute, sym) == TypeAnnotations.AnnotationType.DECLARATION) {
5960                     log.error(ai.pos(), Errors.AnnotationTypeNotApplicableToType(ai.type));
5961                 }
5962             }
5963         }
5964     }
5965 
5966     // <editor-fold desc="post-attribution visitor">
5967 
5968     /**
5969      * Handle missing types/symbols in an AST. This routine is useful when
5970      * the compiler has encountered some errors (which might have ended up
5971      * terminating attribution abruptly); if the compiler is used in fail-over
5972      * mode (e.g. by an IDE) and the AST contains semantic errors, this routine
5973      * prevents NPE to be propagated during subsequent compilation steps.
5974      */
5975     public void postAttr(JCTree tree) {
5976         new PostAttrAnalyzer().scan(tree);
5977     }
5978 
5979     class PostAttrAnalyzer extends TreeScanner {
5980 
5981         private void initTypeIfNeeded(JCTree that) {
5982             if (that.type == null) {
5983                 if (that.hasTag(METHODDEF)) {
5984                     that.type = dummyMethodType((JCMethodDecl)that);
5985                 } else {
5986                     that.type = syms.unknownType;
5987                 }
5988             }
5989         }
5990 
5991         /* Construct a dummy method type. If we have a method declaration,
5992          * and the declared return type is void, then use that return type
5993          * instead of UNKNOWN to avoid spurious error messages in lambda
5994          * bodies (see:JDK-8041704).
5995          */
5996         private Type dummyMethodType(JCMethodDecl md) {
5997             Type restype = syms.unknownType;
5998             if (md != null && md.restype != null && md.restype.hasTag(TYPEIDENT)) {
5999                 JCPrimitiveTypeTree prim = (JCPrimitiveTypeTree)md.restype;
6000                 if (prim.typetag == VOID)
6001                     restype = syms.voidType;
6002             }
6003             return new MethodType(List.nil(), restype,
6004                                   List.nil(), syms.methodClass);
6005         }
6006         private Type dummyMethodType() {
6007             return dummyMethodType(null);
6008         }
6009 
6010         @Override
6011         public void scan(JCTree tree) {
6012             if (tree == null) return;
6013             if (tree instanceof JCExpression) {
6014                 initTypeIfNeeded(tree);
6015             }
6016             super.scan(tree);
6017         }
6018 
6019         @Override
6020         public void visitIdent(JCIdent that) {
6021             if (that.sym == null) {
6022                 that.sym = syms.unknownSymbol;
6023             }
6024         }
6025 
6026         @Override
6027         public void visitSelect(JCFieldAccess that) {
6028             if (that.sym == null) {
6029                 that.sym = syms.unknownSymbol;
6030             }
6031             super.visitSelect(that);
6032         }
6033 
6034         @Override
6035         public void visitClassDef(JCClassDecl that) {
6036             initTypeIfNeeded(that);
6037             if (that.sym == null) {
6038                 that.sym = new ClassSymbol(0, that.name, that.type, syms.noSymbol);
6039             }
6040             super.visitClassDef(that);
6041         }
6042 
6043         @Override
6044         public void visitMethodDef(JCMethodDecl that) {
6045             initTypeIfNeeded(that);
6046             if (that.sym == null) {
6047                 that.sym = new MethodSymbol(0, that.name, that.type, syms.noSymbol);
6048             }
6049             super.visitMethodDef(that);
6050         }
6051 
6052         @Override
6053         public void visitVarDef(JCVariableDecl that) {
6054             initTypeIfNeeded(that);
6055             if (that.sym == null) {
6056                 that.sym = new VarSymbol(0, that.name, that.type, syms.noSymbol);
6057                 that.sym.adr = 0;
6058             }
6059             if (that.vartype == null) {
6060                 that.vartype = make.at(Position.NOPOS).Erroneous();
6061             }
6062             super.visitVarDef(that);
6063         }
6064 
6065         @Override
6066         public void visitBindingPattern(JCBindingPattern that) {
6067             initTypeIfNeeded(that);
6068             initTypeIfNeeded(that.var);
6069             if (that.var.sym == null) {
6070                 that.var.sym = new BindingSymbol(0, that.var.name, that.var.type, syms.noSymbol);
6071                 that.var.sym.adr = 0;
6072             }
6073             super.visitBindingPattern(that);
6074         }
6075 
6076         @Override
6077         public void visitRecordPattern(JCRecordPattern that) {
6078             initTypeIfNeeded(that);
6079             if (that.record == null) {
6080                 that.record = new ClassSymbol(0, TreeInfo.name(that.deconstructor),
6081                                               that.type, syms.noSymbol);
6082             }
6083             if (that.fullComponentTypes == null) {
6084                 that.fullComponentTypes = List.nil();
6085             }
6086             super.visitRecordPattern(that);
6087         }
6088 
6089         @Override
6090         public void visitNewClass(JCNewClass that) {
6091             if (that.constructor == null) {
6092                 that.constructor = new MethodSymbol(0, names.init,
6093                         dummyMethodType(), syms.noSymbol);
6094             }
6095             if (that.constructorType == null) {
6096                 that.constructorType = syms.unknownType;
6097             }
6098             super.visitNewClass(that);
6099         }
6100 
6101         @Override
6102         public void visitAssignop(JCAssignOp that) {
6103             if (that.operator == null) {
6104                 that.operator = new OperatorSymbol(names.empty, dummyMethodType(),
6105                         -1, syms.noSymbol);
6106             }
6107             super.visitAssignop(that);
6108         }
6109 
6110         @Override
6111         public void visitBinary(JCBinary that) {
6112             if (that.operator == null) {
6113                 that.operator = new OperatorSymbol(names.empty, dummyMethodType(),
6114                         -1, syms.noSymbol);
6115             }
6116             super.visitBinary(that);
6117         }
6118 
6119         @Override
6120         public void visitUnary(JCUnary that) {
6121             if (that.operator == null) {
6122                 that.operator = new OperatorSymbol(names.empty, dummyMethodType(),
6123                         -1, syms.noSymbol);
6124             }
6125             super.visitUnary(that);
6126         }
6127 
6128         @Override
6129         public void visitReference(JCMemberReference that) {
6130             super.visitReference(that);
6131             if (that.sym == null) {
6132                 that.sym = new MethodSymbol(0, names.empty, dummyMethodType(),
6133                         syms.noSymbol);
6134             }
6135         }
6136     }
6137     // </editor-fold>
6138 
6139     public void setPackageSymbols(JCExpression pid, Symbol pkg) {
6140         new TreeScanner() {
6141             Symbol packge = pkg;
6142             @Override
6143             public void visitIdent(JCIdent that) {
6144                 that.sym = packge;
6145             }
6146 
6147             @Override
6148             public void visitSelect(JCFieldAccess that) {
6149                 that.sym = packge;
6150                 packge = packge.owner;
6151                 super.visitSelect(that);
6152             }
6153         }.scan(pid);
6154     }
6155 
6156 }