1 /*
   2  * Copyright (c) 1999, 2022, 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 
  32 import javax.lang.model.element.ElementKind;
  33 import javax.tools.JavaFileObject;
  34 
  35 import com.sun.source.tree.CaseTree;
  36 import com.sun.source.tree.IdentifierTree;
  37 import com.sun.source.tree.MemberReferenceTree.ReferenceMode;
  38 import com.sun.source.tree.MemberSelectTree;
  39 import com.sun.source.tree.TreeVisitor;
  40 import com.sun.source.util.SimpleTreeVisitor;
  41 import com.sun.tools.javac.code.*;
  42 import com.sun.tools.javac.code.Lint.LintCategory;
  43 import com.sun.tools.javac.code.Scope.WriteableScope;
  44 import com.sun.tools.javac.code.Source.Feature;
  45 import com.sun.tools.javac.code.Symbol.*;
  46 import com.sun.tools.javac.code.Type.*;
  47 import com.sun.tools.javac.code.Type.ClassType.Flavor;
  48 import com.sun.tools.javac.code.TypeMetadata.Annotations;
  49 import com.sun.tools.javac.code.Types.FunctionDescriptorLookupError;
  50 import com.sun.tools.javac.comp.ArgumentAttr.LocalCacheContext;
  51 import com.sun.tools.javac.comp.Check.CheckContext;
  52 import com.sun.tools.javac.comp.DeferredAttr.AttrMode;
  53 import com.sun.tools.javac.comp.MatchBindingsComputer.MatchBindings;
  54 import com.sun.tools.javac.jvm.*;
  55 
  56 import static com.sun.tools.javac.resources.CompilerProperties.Fragments.Diamond;
  57 import static com.sun.tools.javac.resources.CompilerProperties.Fragments.DiamondInvalidArg;
  58 import static com.sun.tools.javac.resources.CompilerProperties.Fragments.DiamondInvalidArgs;
  59 
  60 import com.sun.tools.javac.resources.CompilerProperties.Errors;
  61 import com.sun.tools.javac.resources.CompilerProperties.Fragments;
  62 import com.sun.tools.javac.resources.CompilerProperties.Warnings;
  63 import com.sun.tools.javac.tree.*;
  64 import com.sun.tools.javac.tree.JCTree.*;
  65 import com.sun.tools.javac.tree.JCTree.JCPolyExpression.*;
  66 import com.sun.tools.javac.util.*;
  67 import com.sun.tools.javac.util.DefinedBy.Api;
  68 import com.sun.tools.javac.util.JCDiagnostic.DiagnosticPosition;
  69 import com.sun.tools.javac.util.JCDiagnostic.Error;
  70 import com.sun.tools.javac.util.JCDiagnostic.Fragment;
  71 import com.sun.tools.javac.util.JCDiagnostic.Warning;
  72 import com.sun.tools.javac.util.List;
  73 
  74 import static com.sun.tools.javac.code.Flags.*;
  75 import static com.sun.tools.javac.code.Flags.ANNOTATION;
  76 import static com.sun.tools.javac.code.Flags.BLOCK;
  77 import static com.sun.tools.javac.code.Kinds.*;
  78 import static com.sun.tools.javac.code.Kinds.Kind.*;
  79 import static com.sun.tools.javac.code.TypeTag.*;
  80 import static com.sun.tools.javac.code.TypeTag.WILDCARD;
  81 import static com.sun.tools.javac.tree.JCTree.Tag.*;
  82 import com.sun.tools.javac.util.JCDiagnostic.DiagnosticFlag;
  83 
  84 /** This is the main context-dependent analysis phase in GJC. It
  85  *  encompasses name resolution, type checking and constant folding as
  86  *  subtasks. Some subtasks involve auxiliary classes.
  87  *  @see Check
  88  *  @see Resolve
  89  *  @see ConstFold
  90  *  @see Infer
  91  *
  92  *  <p><b>This is NOT part of any supported API.
  93  *  If you write code that depends on this, you do so at your own risk.
  94  *  This code and its internal interfaces are subject to change or
  95  *  deletion without notice.</b>
  96  */
  97 public class Attr extends JCTree.Visitor {
  98     protected static final Context.Key<Attr> attrKey = new Context.Key<>();
  99 
 100     final Names names;
 101     final Log log;
 102     final Symtab syms;
 103     final Resolve rs;
 104     final Operators operators;
 105     final Infer infer;
 106     final Analyzer analyzer;
 107     final DeferredAttr deferredAttr;
 108     final Check chk;
 109     final Flow flow;
 110     final MemberEnter memberEnter;
 111     final TypeEnter typeEnter;
 112     final TreeMaker make;
 113     final ConstFold cfolder;
 114     final Enter enter;
 115     final Target target;
 116     final Types types;
 117     final Preview preview;
 118     final JCDiagnostic.Factory diags;
 119     final TypeAnnotations typeAnnotations;
 120     final DeferredLintHandler deferredLintHandler;
 121     final TypeEnvs typeEnvs;
 122     final Dependencies dependencies;
 123     final Annotate annotate;
 124     final ArgumentAttr argumentAttr;
 125     final MatchBindingsComputer matchBindingsComputer;
 126     final AttrRecover attrRecover;
 127 
 128     public static Attr instance(Context context) {
 129         Attr instance = context.get(attrKey);
 130         if (instance == null)
 131             instance = new Attr(context);
 132         return instance;
 133     }
 134 
 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         allowPoly = Feature.POLY.allowedInSource(source);
 170         allowTypeAnnos = Feature.TYPE_ANNOTATIONS.allowedInSource(source);
 171         allowLambda = Feature.LAMBDA.allowedInSource(source);
 172         allowDefaultMethods = Feature.DEFAULT_METHODS.allowedInSource(source);
 173         allowStaticInterfaceMethods = Feature.STATIC_INTERFACE_METHODS.allowedInSource(source);
 174         allowPrimitiveClasses = Feature.PRIMITIVE_CLASSES.allowedInSource(source);
 175         allowReifiableTypesInInstanceof = Feature.REIFIABLE_TYPES_INSTANCEOF.allowedInSource(source);
 176         allowRecords = Feature.RECORDS.allowedInSource(source);
 177         allowPatternSwitch = (preview.isEnabled() || !preview.isPreview(Feature.PATTERN_SWITCH)) &&
 178                              Feature.PATTERN_SWITCH.allowedInSource(source);
 179         sourceName = source.name;
 180         useBeforeDeclarationWarning = options.isSet("useBeforeDeclarationWarning");
 181 
 182         statInfo = new ResultInfo(KindSelector.NIL, Type.noType);
 183         varAssignmentInfo = new ResultInfo(KindSelector.ASG, Type.noType);
 184         unknownExprInfo = new ResultInfo(KindSelector.VAL, Type.noType);
 185         methodAttrInfo = new MethodAttrInfo();
 186         unknownTypeInfo = new ResultInfo(KindSelector.TYP, Type.noType);
 187         unknownTypeExprInfo = new ResultInfo(KindSelector.VAL_TYP, Type.noType);
 188         recoveryInfo = new RecoveryInfo(deferredAttr.emptyDeferredAttrContext);
 189     }
 190 
 191     /** Switch: support target-typing inference
 192      */
 193     boolean allowPoly;
 194 
 195     /** Switch: support type annotations.
 196      */
 197     boolean allowTypeAnnos;
 198 
 199     /** Switch: support lambda expressions ?
 200      */
 201     boolean allowLambda;
 202 
 203     /** Switch: support default methods ?
 204      */
 205     boolean allowDefaultMethods;
 206 
 207     /** Switch: allow primitive classes ?
 208      */
 209     boolean allowPrimitiveClasses;
 210 
 211     /** Switch: static interface methods enabled?
 212      */
 213     boolean allowStaticInterfaceMethods;
 214 
 215     /** Switch: reifiable types in instanceof enabled?
 216      */
 217     boolean allowReifiableTypesInInstanceof;
 218 
 219     /** Are records allowed
 220      */
 221     private final boolean allowRecords;
 222 
 223     /** Are patterns in switch allowed
 224      */
 225     private final boolean allowPatternSwitch;
 226 
 227     /**
 228      * Switch: warn about use of variable before declaration?
 229      * RFE: 6425594
 230      */
 231     boolean useBeforeDeclarationWarning;
 232 
 233     /**
 234      * Switch: name of source level; used for error reporting.
 235      */
 236     String sourceName;
 237 
 238     /** Check kind and type of given tree against protokind and prototype.
 239      *  If check succeeds, store type in tree and return it.
 240      *  If check fails, store errType in tree and return it.
 241      *  No checks are performed if the prototype is a method type.
 242      *  It is not necessary in this case since we know that kind and type
 243      *  are correct.
 244      *
 245      *  @param tree     The tree whose kind and type is checked
 246      *  @param found    The computed type of the tree
 247      *  @param ownkind  The computed kind of the tree
 248      *  @param resultInfo  The expected result of the tree
 249      */
 250     Type check(final JCTree tree,
 251                final Type found,
 252                final KindSelector ownkind,
 253                final ResultInfo resultInfo) {
 254         InferenceContext inferenceContext = resultInfo.checkContext.inferenceContext();
 255         Type owntype;
 256         boolean shouldCheck = !found.hasTag(ERROR) &&
 257                 !resultInfo.pt.hasTag(METHOD) &&
 258                 !resultInfo.pt.hasTag(FORALL);
 259         if (shouldCheck && !ownkind.subset(resultInfo.pkind)) {
 260             log.error(tree.pos(),
 261                       Errors.UnexpectedType(resultInfo.pkind.kindNames(),
 262                                             ownkind.kindNames()));
 263             owntype = types.createErrorType(found);
 264         } else if (allowPoly && inferenceContext.free(found)) {
 265             //delay the check if there are inference variables in the found type
 266             //this means we are dealing with a partially inferred poly expression
 267             owntype = shouldCheck ? resultInfo.pt : found;
 268             if (resultInfo.checkMode.installPostInferenceHook()) {
 269                 inferenceContext.addFreeTypeListener(List.of(found),
 270                         instantiatedContext -> {
 271                             ResultInfo pendingResult =
 272                                     resultInfo.dup(inferenceContext.asInstType(resultInfo.pt));
 273                             check(tree, inferenceContext.asInstType(found), ownkind, pendingResult);
 274                         });
 275             }
 276         } else {
 277             owntype = shouldCheck ?
 278             resultInfo.check(tree, found) :
 279             found;
 280         }
 281         if (resultInfo.checkMode.updateTreeType()) {
 282             tree.type = owntype;
 283         }
 284         return owntype;
 285     }
 286 
 287     /** Is given blank final variable assignable, i.e. in a scope where it
 288      *  may be assigned to even though it is final?
 289      *  @param v      The blank final variable.
 290      *  @param env    The current environment.
 291      */
 292     boolean isAssignableAsBlankFinal(VarSymbol v, Env<AttrContext> env) {
 293         Symbol owner = env.info.scope.owner;
 294            // owner refers to the innermost variable, method or
 295            // initializer block declaration at this point.
 296         boolean isAssignable =
 297             v.owner == owner
 298             ||
 299             ((owner.name == names.init ||    // i.e. we are in a constructor
 300               owner.kind == VAR ||           // i.e. we are in a variable initializer
 301               (owner.flags() & BLOCK) != 0)  // i.e. we are in an initializer block
 302              &&
 303              v.owner == owner.owner
 304              &&
 305              ((v.flags() & STATIC) != 0) == Resolve.isStatic(env));
 306         boolean insideCompactConstructor = env.enclMethod != null && TreeInfo.isCompactConstructor(env.enclMethod);
 307         return isAssignable & !insideCompactConstructor;
 308     }
 309 
 310     /** Check that variable can be assigned to.
 311      *  @param pos    The current source code position.
 312      *  @param v      The assigned variable
 313      *  @param base   If the variable is referred to in a Select, the part
 314      *                to the left of the `.', null otherwise.
 315      *  @param env    The current environment.
 316      */
 317     void checkAssignable(DiagnosticPosition pos, VarSymbol v, JCTree base, Env<AttrContext> env) {
 318         if (v.name == names._this) {
 319             log.error(pos, Errors.CantAssignValToThis);
 320         } else if ((v.flags() & FINAL) != 0 &&
 321             ((v.flags() & HASINIT) != 0
 322              ||
 323              !((base == null ||
 324                TreeInfo.isThisQualifier(base)) &&
 325                isAssignableAsBlankFinal(v, env)))) {
 326             if (v.isResourceVariable()) { //TWR resource
 327                 log.error(pos, Errors.TryResourceMayNotBeAssigned(v));
 328             } else {
 329                 log.error(pos, Errors.CantAssignValToFinalVar(v));
 330             }
 331         }
 332     }
 333 
 334     /** Does tree represent a static reference to an identifier?
 335      *  It is assumed that tree is either a SELECT or an IDENT.
 336      *  We have to weed out selects from non-type names here.
 337      *  @param tree    The candidate tree.
 338      */
 339     boolean isStaticReference(JCTree tree) {
 340         if (tree.hasTag(SELECT)) {
 341             Symbol lsym = TreeInfo.symbol(((JCFieldAccess) tree).selected);
 342             if (lsym == null || lsym.kind != TYP) {
 343                 return false;
 344             }
 345         }
 346         return true;
 347     }
 348 
 349     /** Is this symbol a type?
 350      */
 351     static boolean isType(Symbol sym) {
 352         return sym != null && sym.kind == TYP;
 353     }
 354 
 355     /** The current `this' symbol.
 356      *  @param env    The current environment.
 357      */
 358     Symbol thisSym(DiagnosticPosition pos, Env<AttrContext> env) {
 359         return rs.resolveSelf(pos, env, env.enclClass.sym, names._this);
 360     }
 361 
 362     /** Attribute a parsed identifier.
 363      * @param tree Parsed identifier name
 364      * @param topLevel The toplevel to use
 365      */
 366     public Symbol attribIdent(JCTree tree, JCCompilationUnit topLevel) {
 367         Env<AttrContext> localEnv = enter.topLevelEnv(topLevel);
 368         localEnv.enclClass = make.ClassDef(make.Modifiers(0),
 369                                            syms.errSymbol.name,
 370                                            null, null, null, null);
 371         localEnv.enclClass.sym = syms.errSymbol;
 372         return attribIdent(tree, localEnv);
 373     }
 374 
 375     /** Attribute a parsed identifier.
 376      * @param tree Parsed identifier name
 377      * @param env The env to use
 378      */
 379     public Symbol attribIdent(JCTree tree, Env<AttrContext> env) {
 380         return tree.accept(identAttributer, env);
 381     }
 382     // where
 383         private TreeVisitor<Symbol,Env<AttrContext>> identAttributer = new IdentAttributer();
 384         private class IdentAttributer extends SimpleTreeVisitor<Symbol,Env<AttrContext>> {
 385             @Override @DefinedBy(Api.COMPILER_TREE)
 386             public Symbol visitMemberSelect(MemberSelectTree node, Env<AttrContext> env) {
 387                 Symbol site = visit(node.getExpression(), env);
 388                 if (site.kind == ERR || site.kind == ABSENT_TYP || site.kind == HIDDEN)
 389                     return site;
 390                 Name name = (Name)node.getIdentifier();
 391                 if (site.kind == PCK) {
 392                     env.toplevel.packge = (PackageSymbol)site;
 393                     return rs.findIdentInPackage(null, env, (TypeSymbol)site, name,
 394                             KindSelector.TYP_PCK);
 395                 } else {
 396                     env.enclClass.sym = (ClassSymbol)site;
 397                     return rs.findMemberType(env, site.asType(), name, (TypeSymbol)site);
 398                 }
 399             }
 400 
 401             @Override @DefinedBy(Api.COMPILER_TREE)
 402             public Symbol visitIdentifier(IdentifierTree node, Env<AttrContext> env) {
 403                 return rs.findIdent(null, env, (Name)node.getName(), KindSelector.TYP_PCK);
 404             }
 405         }
 406 
 407     public Type coerce(Type etype, Type ttype) {
 408         return cfolder.coerce(etype, ttype);
 409     }
 410 
 411     public Type attribType(JCTree node, TypeSymbol sym) {
 412         Env<AttrContext> env = typeEnvs.get(sym);
 413         Env<AttrContext> localEnv = env.dup(node, env.info.dup());
 414         return attribTree(node, localEnv, unknownTypeInfo);
 415     }
 416 
 417     public Type attribImportQualifier(JCImport tree, Env<AttrContext> env) {
 418         // Attribute qualifying package or class.
 419         JCFieldAccess s = (JCFieldAccess)tree.qualid;
 420         return attribTree(s.selected, env,
 421                           new ResultInfo(tree.staticImport ?
 422                                          KindSelector.TYP : KindSelector.TYP_PCK,
 423                        Type.noType));
 424     }
 425 
 426     public Env<AttrContext> attribExprToTree(JCTree expr, Env<AttrContext> env, JCTree tree) {
 427         return attribToTree(expr, env, tree, unknownExprInfo);
 428     }
 429 
 430     public Env<AttrContext> attribStatToTree(JCTree stmt, Env<AttrContext> env, JCTree tree) {
 431         return attribToTree(stmt, env, tree, statInfo);
 432     }
 433 
 434     private Env<AttrContext> attribToTree(JCTree root, Env<AttrContext> env, JCTree tree, ResultInfo resultInfo) {
 435         breakTree = tree;
 436         JavaFileObject prev = log.useSource(env.toplevel.sourcefile);
 437         try {
 438             deferredAttr.attribSpeculative(root, env, resultInfo,
 439                     null, DeferredAttr.AttributionMode.ATTRIB_TO_TREE,
 440                     argumentAttr.withLocalCacheContext());
 441             attrRecover.doRecovery();
 442         } catch (BreakAttr b) {
 443             return b.env;
 444         } catch (AssertionError ae) {
 445             if (ae.getCause() instanceof BreakAttr breakAttr) {
 446                 return breakAttr.env;
 447             } else {
 448                 throw ae;
 449             }
 450         } finally {
 451             breakTree = null;
 452             log.useSource(prev);
 453         }
 454         return env;
 455     }
 456 
 457     private JCTree breakTree = null;
 458 
 459     private static class BreakAttr extends RuntimeException {
 460         static final long serialVersionUID = -6924771130405446405L;
 461         private transient Env<AttrContext> env;
 462         private BreakAttr(Env<AttrContext> env) {
 463             this.env = env;
 464         }
 465     }
 466 
 467     /**
 468      * Mode controlling behavior of Attr.Check
 469      */
 470     enum CheckMode {
 471 
 472         NORMAL,
 473 
 474         /**
 475          * Mode signalling 'fake check' - skip tree update. A side-effect of this mode is
 476          * that the captured var cache in {@code InferenceContext} will be used in read-only
 477          * mode when performing inference checks.
 478          */
 479         NO_TREE_UPDATE {
 480             @Override
 481             public boolean updateTreeType() {
 482                 return false;
 483             }
 484         },
 485         /**
 486          * Mode signalling that caller will manage free types in tree decorations.
 487          */
 488         NO_INFERENCE_HOOK {
 489             @Override
 490             public boolean installPostInferenceHook() {
 491                 return false;
 492             }
 493         };
 494 
 495         public boolean updateTreeType() {
 496             return true;
 497         }
 498         public boolean installPostInferenceHook() {
 499             return true;
 500         }
 501     }
 502 
 503 
 504     class ResultInfo {
 505         final KindSelector pkind;
 506         final Type pt;
 507         final CheckContext checkContext;
 508         final CheckMode checkMode;
 509 
 510         ResultInfo(KindSelector pkind, Type pt) {
 511             this(pkind, pt, chk.basicHandler, CheckMode.NORMAL);
 512         }
 513 
 514         ResultInfo(KindSelector pkind, Type pt, CheckMode checkMode) {
 515             this(pkind, pt, chk.basicHandler, checkMode);
 516         }
 517 
 518         protected ResultInfo(KindSelector pkind,
 519                              Type pt, CheckContext checkContext) {
 520             this(pkind, pt, checkContext, CheckMode.NORMAL);
 521         }
 522 
 523         protected ResultInfo(KindSelector pkind,
 524                              Type pt, CheckContext checkContext, CheckMode checkMode) {
 525             this.pkind = pkind;
 526             this.pt = pt;
 527             this.checkContext = checkContext;
 528             this.checkMode = checkMode;
 529         }
 530 
 531         /**
 532          * Should {@link Attr#attribTree} use the {@ArgumentAttr} visitor instead of this one?
 533          * @param tree The tree to be type-checked.
 534          * @return true if {@ArgumentAttr} should be used.
 535          */
 536         protected boolean needsArgumentAttr(JCTree tree) { return false; }
 537 
 538         protected Type check(final DiagnosticPosition pos, final Type found) {
 539             return chk.checkType(pos, found, pt, checkContext);
 540         }
 541 
 542         protected ResultInfo dup(Type newPt) {
 543             return new ResultInfo(pkind, newPt, checkContext, checkMode);
 544         }
 545 
 546         protected ResultInfo dup(CheckContext newContext) {
 547             return new ResultInfo(pkind, pt, newContext, checkMode);
 548         }
 549 
 550         protected ResultInfo dup(Type newPt, CheckContext newContext) {
 551             return new ResultInfo(pkind, newPt, newContext, checkMode);
 552         }
 553 
 554         protected ResultInfo dup(Type newPt, CheckContext newContext, CheckMode newMode) {
 555             return new ResultInfo(pkind, newPt, newContext, newMode);
 556         }
 557 
 558         protected ResultInfo dup(CheckMode newMode) {
 559             return new ResultInfo(pkind, pt, checkContext, newMode);
 560         }
 561 
 562         @Override
 563         public String toString() {
 564             if (pt != null) {
 565                 return pt.toString();
 566             } else {
 567                 return "";
 568             }
 569         }
 570     }
 571 
 572     class MethodAttrInfo extends ResultInfo {
 573         public MethodAttrInfo() {
 574             this(chk.basicHandler);
 575         }
 576 
 577         public MethodAttrInfo(CheckContext checkContext) {
 578             super(KindSelector.VAL, Infer.anyPoly, checkContext);
 579         }
 580 
 581         @Override
 582         protected boolean needsArgumentAttr(JCTree tree) {
 583             return true;
 584         }
 585 
 586         protected ResultInfo dup(Type newPt) {
 587             throw new IllegalStateException();
 588         }
 589 
 590         protected ResultInfo dup(CheckContext newContext) {
 591             return new MethodAttrInfo(newContext);
 592         }
 593 
 594         protected ResultInfo dup(Type newPt, CheckContext newContext) {
 595             throw new IllegalStateException();
 596         }
 597 
 598         protected ResultInfo dup(Type newPt, CheckContext newContext, CheckMode newMode) {
 599             throw new IllegalStateException();
 600         }
 601 
 602         protected ResultInfo dup(CheckMode newMode) {
 603             throw new IllegalStateException();
 604         }
 605     }
 606 
 607     class RecoveryInfo extends ResultInfo {
 608 
 609         public RecoveryInfo(final DeferredAttr.DeferredAttrContext deferredAttrContext) {
 610             this(deferredAttrContext, Type.recoveryType);
 611         }
 612 
 613         public RecoveryInfo(final DeferredAttr.DeferredAttrContext deferredAttrContext, Type pt) {
 614             super(KindSelector.VAL, pt, new Check.NestedCheckContext(chk.basicHandler) {
 615                 @Override
 616                 public DeferredAttr.DeferredAttrContext deferredAttrContext() {
 617                     return deferredAttrContext;
 618                 }
 619                 @Override
 620                 public boolean compatible(Type found, Type req, Warner warn) {
 621                     return true;
 622                 }
 623                 @Override
 624                 public void report(DiagnosticPosition pos, JCDiagnostic details) {
 625                     boolean needsReport = pt == Type.recoveryType ||
 626                             (details.getDiagnosticPosition() != null &&
 627                             details.getDiagnosticPosition().getTree().hasTag(LAMBDA));
 628                     if (needsReport) {
 629                         chk.basicHandler.report(pos, details);
 630                     }
 631                 }
 632             });
 633         }
 634     }
 635 
 636     final ResultInfo statInfo;
 637     final ResultInfo varAssignmentInfo;
 638     final ResultInfo methodAttrInfo;
 639     final ResultInfo unknownExprInfo;
 640     final ResultInfo unknownTypeInfo;
 641     final ResultInfo unknownTypeExprInfo;
 642     final ResultInfo recoveryInfo;
 643 
 644     Type pt() {
 645         return resultInfo.pt;
 646     }
 647 
 648     KindSelector pkind() {
 649         return resultInfo.pkind;
 650     }
 651 
 652 /* ************************************************************************
 653  * Visitor methods
 654  *************************************************************************/
 655 
 656     /** Visitor argument: the current environment.
 657      */
 658     Env<AttrContext> env;
 659 
 660     /** Visitor argument: the currently expected attribution result.
 661      */
 662     ResultInfo resultInfo;
 663 
 664     /** Visitor result: the computed type.
 665      */
 666     Type result;
 667 
 668     MatchBindings matchBindings = MatchBindingsComputer.EMPTY;
 669 
 670     /** Visitor method: attribute a tree, catching any completion failure
 671      *  exceptions. Return the tree's type.
 672      *
 673      *  @param tree    The tree to be visited.
 674      *  @param env     The environment visitor argument.
 675      *  @param resultInfo   The result info visitor argument.
 676      */
 677     Type attribTree(JCTree tree, Env<AttrContext> env, ResultInfo resultInfo) {
 678         Env<AttrContext> prevEnv = this.env;
 679         ResultInfo prevResult = this.resultInfo;
 680         try {
 681             this.env = env;
 682             this.resultInfo = resultInfo;
 683             if (resultInfo.needsArgumentAttr(tree)) {
 684                 result = argumentAttr.attribArg(tree, env);
 685             } else {
 686                 tree.accept(this);
 687             }
 688             matchBindings = matchBindingsComputer.finishBindings(tree,
 689                                                                  matchBindings);
 690             if (tree == breakTree &&
 691                     resultInfo.checkContext.deferredAttrContext().mode == AttrMode.CHECK) {
 692                 breakTreeFound(copyEnv(env));
 693             }
 694             return result;
 695         } catch (CompletionFailure ex) {
 696             tree.type = syms.errType;
 697             return chk.completionError(tree.pos(), ex);
 698         } finally {
 699             this.env = prevEnv;
 700             this.resultInfo = prevResult;
 701         }
 702     }
 703 
 704     protected void breakTreeFound(Env<AttrContext> env) {
 705         throw new BreakAttr(env);
 706     }
 707 
 708     Env<AttrContext> copyEnv(Env<AttrContext> env) {
 709         Env<AttrContext> newEnv =
 710                 env.dup(env.tree, env.info.dup(copyScope(env.info.scope)));
 711         if (newEnv.outer != null) {
 712             newEnv.outer = copyEnv(newEnv.outer);
 713         }
 714         return newEnv;
 715     }
 716 
 717     WriteableScope copyScope(WriteableScope sc) {
 718         WriteableScope newScope = WriteableScope.create(sc.owner);
 719         List<Symbol> elemsList = List.nil();
 720         for (Symbol sym : sc.getSymbols()) {
 721             elemsList = elemsList.prepend(sym);
 722         }
 723         for (Symbol s : elemsList) {
 724             newScope.enter(s);
 725         }
 726         return newScope;
 727     }
 728 
 729     /** Derived visitor method: attribute an expression tree.
 730      */
 731     public Type attribExpr(JCTree tree, Env<AttrContext> env, Type pt) {
 732         return attribTree(tree, env, new ResultInfo(KindSelector.VAL, !pt.hasTag(ERROR) ? pt : Type.noType));
 733     }
 734 
 735     /** Derived visitor method: attribute an expression tree with
 736      *  no constraints on the computed type.
 737      */
 738     public Type attribExpr(JCTree tree, Env<AttrContext> env) {
 739         return attribTree(tree, env, unknownExprInfo);
 740     }
 741 
 742     /** Derived visitor method: attribute a type tree.
 743      */
 744     public Type attribType(JCTree tree, Env<AttrContext> env) {
 745         Type result = attribType(tree, env, Type.noType);
 746         return result;
 747     }
 748 
 749     /** Derived visitor method: attribute a type tree.
 750      */
 751     Type attribType(JCTree tree, Env<AttrContext> env, Type pt) {
 752         Type result = attribTree(tree, env, new ResultInfo(KindSelector.TYP, pt));
 753         return result;
 754     }
 755 
 756     /** Derived visitor method: attribute a statement or definition tree.
 757      */
 758     public Type attribStat(JCTree tree, Env<AttrContext> env) {
 759         Env<AttrContext> analyzeEnv = analyzer.copyEnvIfNeeded(tree, env);
 760         Type result = attribTree(tree, env, statInfo);
 761         analyzer.analyzeIfNeeded(tree, analyzeEnv);
 762         attrRecover.doRecovery();
 763         return result;
 764     }
 765 
 766     /** Attribute a list of expressions, returning a list of types.
 767      */
 768     List<Type> attribExprs(List<JCExpression> trees, Env<AttrContext> env, Type pt) {
 769         ListBuffer<Type> ts = new ListBuffer<>();
 770         for (List<JCExpression> l = trees; l.nonEmpty(); l = l.tail)
 771             ts.append(attribExpr(l.head, env, pt));
 772         return ts.toList();
 773     }
 774 
 775     /** Attribute a list of statements, returning nothing.
 776      */
 777     <T extends JCTree> void attribStats(List<T> trees, Env<AttrContext> env) {
 778         for (List<T> l = trees; l.nonEmpty(); l = l.tail)
 779             attribStat(l.head, env);
 780     }
 781 
 782     /** Attribute the arguments in a method call, returning the method kind.
 783      */
 784     KindSelector attribArgs(KindSelector initialKind, List<JCExpression> trees, Env<AttrContext> env, ListBuffer<Type> argtypes) {
 785         KindSelector kind = initialKind;
 786         for (JCExpression arg : trees) {
 787             Type argtype = chk.checkNonVoid(arg, attribTree(arg, env, allowPoly ? methodAttrInfo : unknownExprInfo));
 788             if (argtype.hasTag(DEFERRED)) {
 789                 kind = KindSelector.of(KindSelector.POLY, kind);
 790             }
 791             argtypes.append(argtype);
 792         }
 793         return kind;
 794     }
 795 
 796     /** Attribute a type argument list, returning a list of types.
 797      *  Caller is responsible for calling checkRefTypes.
 798      */
 799     List<Type> attribAnyTypes(List<JCExpression> trees, Env<AttrContext> env) {
 800         ListBuffer<Type> argtypes = new ListBuffer<>();
 801         for (List<JCExpression> l = trees; l.nonEmpty(); l = l.tail)
 802             argtypes.append(attribType(l.head, env));
 803         return argtypes.toList();
 804     }
 805 
 806     /** Attribute a type argument list, returning a list of types.
 807      *  Check that all the types are references.
 808      */
 809     List<Type> attribTypes(List<JCExpression> trees, Env<AttrContext> env) {
 810         List<Type> types = attribAnyTypes(trees, env);
 811         return chk.checkRefTypes(trees, types);
 812     }
 813 
 814     /**
 815      * Attribute type variables (of generic classes or methods).
 816      * Compound types are attributed later in attribBounds.
 817      * @param typarams the type variables to enter
 818      * @param env      the current environment
 819      */
 820     void attribTypeVariables(List<JCTypeParameter> typarams, Env<AttrContext> env, boolean checkCyclic) {
 821         for (JCTypeParameter tvar : typarams) {
 822             TypeVar a = (TypeVar)tvar.type;
 823             a.tsym.flags_field |= UNATTRIBUTED;
 824             a.setUpperBound(Type.noType);
 825             if (!tvar.bounds.isEmpty()) {
 826                 List<Type> bounds = List.of(chk.checkRefType(tvar.bounds.head, attribType(tvar.bounds.head, env), false));
 827                 for (JCExpression bound : tvar.bounds.tail)
 828                     bounds = bounds.prepend(chk.checkRefType(bound, attribType(bound, env), false));
 829                 types.setBounds(a, bounds.reverse());
 830             } else {
 831                 // if no bounds are given, assume a single bound of
 832                 // java.lang.Object.
 833                 types.setBounds(a, List.of(syms.objectType));
 834             }
 835             a.tsym.flags_field &= ~UNATTRIBUTED;
 836         }
 837         if (checkCyclic) {
 838             for (JCTypeParameter tvar : typarams) {
 839                 chk.checkNonCyclic(tvar.pos(), (TypeVar)tvar.type);
 840             }
 841         }
 842     }
 843 
 844     /**
 845      * Attribute the type references in a list of annotations.
 846      */
 847     void attribAnnotationTypes(List<JCAnnotation> annotations,
 848                                Env<AttrContext> env) {
 849         for (List<JCAnnotation> al = annotations; al.nonEmpty(); al = al.tail) {
 850             JCAnnotation a = al.head;
 851             attribType(a.annotationType, env);
 852         }
 853     }
 854 
 855     /**
 856      * Attribute a "lazy constant value".
 857      *  @param env         The env for the const value
 858      *  @param variable    The initializer for the const value
 859      *  @param type        The expected type, or null
 860      *  @see VarSymbol#setLazyConstValue
 861      */
 862     public Object attribLazyConstantValue(Env<AttrContext> env,
 863                                       JCVariableDecl variable,
 864                                       Type type) {
 865 
 866         DiagnosticPosition prevLintPos
 867                 = deferredLintHandler.setPos(variable.pos());
 868 
 869         final JavaFileObject prevSource = log.useSource(env.toplevel.sourcefile);
 870         try {
 871             Type itype = attribExpr(variable.init, env, type);
 872             if (variable.isImplicitlyTyped()) {
 873                 //fixup local variable type
 874                 type = variable.type = variable.sym.type = chk.checkLocalVarType(variable, itype.baseType(), variable.name);
 875             }
 876             if (itype.constValue() != null) {
 877                 return coerce(itype, type).constValue();
 878             } else {
 879                 return null;
 880             }
 881         } finally {
 882             log.useSource(prevSource);
 883             deferredLintHandler.setPos(prevLintPos);
 884         }
 885     }
 886 
 887     /** Attribute type reference in an `extends' or `implements' clause.
 888      *  Supertypes of anonymous inner classes are usually already attributed.
 889      *
 890      *  @param tree              The tree making up the type reference.
 891      *  @param env               The environment current at the reference.
 892      *  @param classExpected     true if only a class is expected here.
 893      *  @param interfaceExpected true if only an interface is expected here.
 894      */
 895     Type attribBase(JCTree tree,
 896                     Env<AttrContext> env,
 897                     boolean classExpected,
 898                     boolean interfaceExpected,
 899                     boolean checkExtensible) {
 900         Type t = tree.type != null ?
 901             tree.type :
 902             attribType(tree, env);
 903         return checkBase(t, tree, env, classExpected, interfaceExpected, checkExtensible);
 904     }
 905     Type checkBase(Type t,
 906                    JCTree tree,
 907                    Env<AttrContext> env,
 908                    boolean classExpected,
 909                    boolean interfaceExpected,
 910                    boolean checkExtensible) {
 911         final DiagnosticPosition pos = tree.hasTag(TYPEAPPLY) ?
 912                 (((JCTypeApply) tree).clazz).pos() : tree.pos();
 913         if (t.tsym.isAnonymous()) {
 914             log.error(pos, Errors.CantInheritFromAnon);
 915             return types.createErrorType(t);
 916         }
 917         if (t.isErroneous())
 918             return t;
 919         if (t.hasTag(TYPEVAR) && !classExpected && !interfaceExpected) {
 920             // check that type variable is already visible
 921             if (t.getUpperBound() == null) {
 922                 log.error(pos, Errors.IllegalForwardRef);
 923                 return types.createErrorType(t);
 924             }
 925         } else {
 926             t = chk.checkClassType(pos, t, checkExtensible);
 927         }
 928         if (interfaceExpected && (t.tsym.flags() & INTERFACE) == 0) {
 929             log.error(pos, Errors.IntfExpectedHere);
 930             // return errType is necessary since otherwise there might
 931             // be undetected cycles which cause attribution to loop
 932             return types.createErrorType(t);
 933         } else if (checkExtensible &&
 934                    classExpected &&
 935                    (t.tsym.flags() & INTERFACE) != 0) {
 936             log.error(pos, Errors.NoIntfExpectedHere);
 937             return types.createErrorType(t);
 938         }
 939         if (checkExtensible &&
 940             ((t.tsym.flags() & FINAL) != 0)) {
 941             log.error(pos,
 942                       Errors.CantInheritFromFinal(t.tsym));
 943         }
 944         chk.checkNonCyclic(pos, t);
 945         return t;
 946     }
 947 
 948     Type attribIdentAsEnumType(Env<AttrContext> env, JCIdent id) {
 949         Assert.check((env.enclClass.sym.flags() & ENUM) != 0);
 950         id.type = env.info.scope.owner.enclClass().type;
 951         id.sym = env.info.scope.owner.enclClass();
 952         return id.type;
 953     }
 954 
 955     public void visitClassDef(JCClassDecl tree) {
 956         Optional<ArgumentAttr.LocalCacheContext> localCacheContext =
 957                 Optional.ofNullable(env.info.attributionMode.isSpeculative ?
 958                         argumentAttr.withLocalCacheContext() : null);
 959         try {
 960             // Local and anonymous classes have not been entered yet, so we need to
 961             // do it now.
 962             if (env.info.scope.owner.kind.matches(KindSelector.VAL_MTH)) {
 963                 enter.classEnter(tree, env);
 964             } else {
 965                 // If this class declaration is part of a class level annotation,
 966                 // as in @MyAnno(new Object() {}) class MyClass {}, enter it in
 967                 // order to simplify later steps and allow for sensible error
 968                 // messages.
 969                 if (env.tree.hasTag(NEWCLASS) && TreeInfo.isInAnnotation(env, tree))
 970                     enter.classEnter(tree, env);
 971             }
 972 
 973             ClassSymbol c = tree.sym;
 974             if (c == null) {
 975                 // exit in case something drastic went wrong during enter.
 976                 result = null;
 977             } else {
 978                 // make sure class has been completed:
 979                 c.complete();
 980 
 981                 // If this class appears as an anonymous class
 982                 // in a superclass constructor call
 983                 // disable implicit outer instance from being passed.
 984                 // (This would be an illegal access to "this before super").
 985                 if (env.info.isSelfCall &&
 986                         env.tree.hasTag(NEWCLASS)) {
 987                     c.flags_field |= NOOUTERTHIS;
 988                 }
 989                 attribClass(tree.pos(), c);
 990                 result = tree.type = c.type;
 991             }
 992         } finally {
 993             localCacheContext.ifPresent(LocalCacheContext::leave);
 994         }
 995     }
 996 
 997     public void visitMethodDef(JCMethodDecl tree) {
 998         MethodSymbol m = tree.sym;
 999         boolean isDefaultMethod = (m.flags() & DEFAULT) != 0;
1000 
1001         Lint lint = env.info.lint.augment(m);
1002         Lint prevLint = chk.setLint(lint);
1003         MethodSymbol prevMethod = chk.setMethod(m);
1004         try {
1005             deferredLintHandler.flush(tree.pos());
1006             chk.checkDeprecatedAnnotation(tree.pos(), m);
1007 
1008 
1009             // Create a new environment with local scope
1010             // for attributing the method.
1011             Env<AttrContext> localEnv = memberEnter.methodEnv(tree, env);
1012             localEnv.info.lint = lint;
1013 
1014             attribStats(tree.typarams, localEnv);
1015 
1016             // If we override any other methods, check that we do so properly.
1017             // JLS ???
1018             if (m.isStatic()) {
1019                 chk.checkHideClashes(tree.pos(), env.enclClass.type, m);
1020             } else {
1021                 chk.checkOverrideClashes(tree.pos(), env.enclClass.type, m);
1022             }
1023             chk.checkOverride(env, tree, m);
1024 
1025             if (isDefaultMethod && types.overridesObjectMethod(m.enclClass(), m)) {
1026                 log.error(tree, Errors.DefaultOverridesObjectMember(m.name, Kinds.kindName(m.location()), m.location()));
1027             }
1028 
1029             // Enter all type parameters into the local method scope.
1030             for (List<JCTypeParameter> l = tree.typarams; l.nonEmpty(); l = l.tail)
1031                 localEnv.info.scope.enterIfAbsent(l.head.type.tsym);
1032 
1033             ClassSymbol owner = env.enclClass.sym;
1034             if ((owner.flags() & ANNOTATION) != 0 &&
1035                     (tree.params.nonEmpty() ||
1036                     tree.recvparam != null))
1037                 log.error(tree.params.nonEmpty() ?
1038                         tree.params.head.pos() :
1039                         tree.recvparam.pos(),
1040                         Errors.IntfAnnotationMembersCantHaveParams);
1041 
1042             // Attribute all value parameters.
1043             for (List<JCVariableDecl> l = tree.params; l.nonEmpty(); l = l.tail) {
1044                 attribStat(l.head, localEnv);
1045             }
1046 
1047             chk.checkVarargsMethodDecl(localEnv, tree);
1048 
1049             // Check that type parameters are well-formed.
1050             chk.validate(tree.typarams, localEnv);
1051 
1052             // Check that result type is well-formed.
1053             if (tree.restype != null && !tree.restype.type.hasTag(VOID))
1054                 chk.validate(tree.restype, localEnv);
1055 
1056             // Check that receiver type is well-formed.
1057             if (tree.recvparam != null) {
1058                 // Use a new environment to check the receiver parameter.
1059                 // Otherwise I get "might not have been initialized" errors.
1060                 // Is there a better way?
1061                 Env<AttrContext> newEnv = memberEnter.methodEnv(tree, env);
1062                 attribType(tree.recvparam, newEnv);
1063                 chk.validate(tree.recvparam, newEnv);
1064             }
1065 
1066             if (env.enclClass.sym.isRecord() && tree.sym.owner.kind == TYP) {
1067                 // lets find if this method is an accessor
1068                 Optional<? extends RecordComponent> recordComponent = env.enclClass.sym.getRecordComponents().stream()
1069                         .filter(rc -> rc.accessor == tree.sym && (rc.accessor.flags_field & GENERATED_MEMBER) == 0).findFirst();
1070                 if (recordComponent.isPresent()) {
1071                     // the method is a user defined accessor lets check that everything is fine
1072                     if (!tree.sym.isPublic()) {
1073                         log.error(tree, Errors.InvalidAccessorMethodInRecord(env.enclClass.sym, Fragments.MethodMustBePublic));
1074                     }
1075                     if (!types.isSameType(tree.sym.type.getReturnType(), recordComponent.get().type)) {
1076                         log.error(tree, Errors.InvalidAccessorMethodInRecord(env.enclClass.sym,
1077                                 Fragments.AccessorReturnTypeDoesntMatch(tree.sym, recordComponent.get())));
1078                     }
1079                     if (tree.sym.type.asMethodType().thrown != null && !tree.sym.type.asMethodType().thrown.isEmpty()) {
1080                         log.error(tree,
1081                                 Errors.InvalidAccessorMethodInRecord(env.enclClass.sym, Fragments.AccessorMethodCantThrowException));
1082                     }
1083                     if (!tree.typarams.isEmpty()) {
1084                         log.error(tree,
1085                                 Errors.InvalidAccessorMethodInRecord(env.enclClass.sym, Fragments.AccessorMethodMustNotBeGeneric));
1086                     }
1087                     if (tree.sym.isStatic()) {
1088                         log.error(tree,
1089                                 Errors.InvalidAccessorMethodInRecord(env.enclClass.sym, Fragments.AccessorMethodMustNotBeStatic));
1090                     }
1091                 }
1092 
1093                 if (tree.name == names.init) {
1094                     // if this a constructor other than the canonical one
1095                     if ((tree.sym.flags_field & RECORD) == 0) {
1096                         JCMethodInvocation app = TreeInfo.firstConstructorCall(tree);
1097                         if (app == null ||
1098                                 TreeInfo.name(app.meth) != names._this ||
1099                                 !checkFirstConstructorStat(app, tree, false)) {
1100                             log.error(tree, Errors.FirstStatementMustBeCallToAnotherConstructor(env.enclClass.sym));
1101                         }
1102                     } else {
1103                         // but if it is the canonical:
1104 
1105                         /* if user generated, then it shouldn't:
1106                          *     - have an accessibility stricter than that of the record type
1107                          *     - explicitly invoke any other constructor
1108                          */
1109                         if ((tree.sym.flags_field & GENERATEDCONSTR) == 0) {
1110                             if (Check.protection(m.flags()) > Check.protection(env.enclClass.sym.flags())) {
1111                                 log.error(tree,
1112                                         (env.enclClass.sym.flags() & AccessFlags) == 0 ?
1113                                             Errors.InvalidCanonicalConstructorInRecord(
1114                                                 Fragments.Canonical,
1115                                                 env.enclClass.sym.name,
1116                                                 Fragments.CanonicalMustNotHaveStrongerAccess("package")
1117                                             ) :
1118                                             Errors.InvalidCanonicalConstructorInRecord(
1119                                                     Fragments.Canonical,
1120                                                     env.enclClass.sym.name,
1121                                                     Fragments.CanonicalMustNotHaveStrongerAccess(asFlagSet(env.enclClass.sym.flags() & AccessFlags))
1122                                             )
1123                                 );
1124                             }
1125 
1126                             JCMethodInvocation app = TreeInfo.firstConstructorCall(tree);
1127                             if (app != null &&
1128                                     (TreeInfo.name(app.meth) == names._this ||
1129                                             TreeInfo.name(app.meth) == names._super) &&
1130                                     checkFirstConstructorStat(app, tree, false)) {
1131                                 log.error(tree, Errors.InvalidCanonicalConstructorInRecord(
1132                                         Fragments.Canonical, env.enclClass.sym.name,
1133                                         Fragments.CanonicalMustNotContainExplicitConstructorInvocation));
1134                             }
1135                         }
1136 
1137                         // also we want to check that no type variables have been defined
1138                         if (!tree.typarams.isEmpty()) {
1139                             log.error(tree, Errors.InvalidCanonicalConstructorInRecord(
1140                                     Fragments.Canonical, env.enclClass.sym.name, Fragments.CanonicalMustNotDeclareTypeVariables));
1141                         }
1142 
1143                         /* and now we need to check that the constructor's arguments are exactly the same as those of the
1144                          * record components
1145                          */
1146                         List<? extends RecordComponent> recordComponents = env.enclClass.sym.getRecordComponents();
1147                         List<Type> recordFieldTypes = TreeInfo.recordFields(env.enclClass).map(vd -> vd.sym.type);
1148                         for (JCVariableDecl param: tree.params) {
1149                             boolean paramIsVarArgs = (param.sym.flags_field & VARARGS) != 0;
1150                             if (!types.isSameType(param.type, recordFieldTypes.head) ||
1151                                     (recordComponents.head.isVarargs() != paramIsVarArgs)) {
1152                                 log.error(param, Errors.InvalidCanonicalConstructorInRecord(
1153                                         Fragments.Canonical, env.enclClass.sym.name,
1154                                         Fragments.TypeMustBeIdenticalToCorrespondingRecordComponentType));
1155                             }
1156                             recordComponents = recordComponents.tail;
1157                             recordFieldTypes = recordFieldTypes.tail;
1158                         }
1159                     }
1160                 }
1161             }
1162 
1163             // annotation method checks
1164             if ((owner.flags() & ANNOTATION) != 0) {
1165                 // annotation method cannot have throws clause
1166                 if (tree.thrown.nonEmpty()) {
1167                     log.error(tree.thrown.head.pos(),
1168                               Errors.ThrowsNotAllowedInIntfAnnotation);
1169                 }
1170                 // annotation method cannot declare type-parameters
1171                 if (tree.typarams.nonEmpty()) {
1172                     log.error(tree.typarams.head.pos(),
1173                               Errors.IntfAnnotationMembersCantHaveTypeParams);
1174                 }
1175                 // validate annotation method's return type (could be an annotation type)
1176                 chk.validateAnnotationType(tree.restype);
1177                 // ensure that annotation method does not clash with members of Object/Annotation
1178                 chk.validateAnnotationMethod(tree.pos(), m);
1179             }
1180 
1181             for (List<JCExpression> l = tree.thrown; l.nonEmpty(); l = l.tail)
1182                 chk.checkType(l.head.pos(), l.head.type, syms.throwableType);
1183 
1184             if (tree.body == null) {
1185                 // Empty bodies are only allowed for
1186                 // abstract, native, or interface methods, or for methods
1187                 // in a retrofit signature class.
1188                 if (tree.defaultValue != null) {
1189                     if ((owner.flags() & ANNOTATION) == 0)
1190                         log.error(tree.pos(),
1191                                   Errors.DefaultAllowedInIntfAnnotationMember);
1192                 }
1193                 if (isDefaultMethod || (tree.sym.flags() & (ABSTRACT | NATIVE)) == 0)
1194                     log.error(tree.pos(), Errors.MissingMethBodyOrDeclAbstract);
1195             } else if ((tree.sym.flags() & (ABSTRACT|DEFAULT|PRIVATE)) == ABSTRACT) {
1196                 if ((owner.flags() & INTERFACE) != 0) {
1197                     log.error(tree.body.pos(), Errors.IntfMethCantHaveBody);
1198                 } else {
1199                     log.error(tree.pos(), Errors.AbstractMethCantHaveBody);
1200                 }
1201             } else if ((tree.mods.flags & NATIVE) != 0) {
1202                 log.error(tree.pos(), Errors.NativeMethCantHaveBody);
1203             } else {
1204                 // Add an implicit super() call unless an explicit call to
1205                 // super(...) or this(...) is given
1206                 // or we are compiling class java.lang.Object.
1207                 if (tree.name == names.init && owner.type != syms.objectType) {
1208                     JCBlock body = tree.body;
1209                     if (body.stats.isEmpty() ||
1210                             TreeInfo.getConstructorInvocationName(body.stats, names, true) == names.empty) {
1211                         JCStatement supCall = make.at(body.pos).Exec(make.Apply(List.nil(),
1212                                 make.Ident(names._super), make.Idents(List.nil())));
1213                         body.stats = body.stats.prepend(supCall);
1214                     } else if ((env.enclClass.sym.flags() & ENUM) != 0 &&
1215                             (tree.mods.flags & GENERATEDCONSTR) == 0 &&
1216                             TreeInfo.isSuperCall(body.stats.head)) {
1217                         // enum constructors are not allowed to call super
1218                         // directly, so make sure there aren't any super calls
1219                         // in enum constructors, except in the compiler
1220                         // generated one.
1221                         log.error(tree.body.stats.head.pos(),
1222                                   Errors.CallToSuperNotAllowedInEnumCtor(env.enclClass.sym));
1223                     } else if ((env.enclClass.sym.flags() & VALUE_CLASS) != 0 &&
1224                         (tree.mods.flags & GENERATEDCONSTR) == 0 &&
1225                         TreeInfo.isSuperCall(body.stats.head)) {
1226                         // value constructors are not allowed to call super directly,
1227                         // but tolerate compiler generated ones, these are ignored during code generation
1228                         log.error(tree.body.stats.head.pos(), Errors.CallToSuperNotAllowedInValueCtor);
1229                     }
1230                     if (env.enclClass.sym.isRecord() && (tree.sym.flags_field & RECORD) != 0) { // we are seeing the canonical constructor
1231                         List<Name> recordComponentNames = TreeInfo.recordFields(env.enclClass).map(vd -> vd.sym.name);
1232                         List<Name> initParamNames = tree.sym.params.map(p -> p.name);
1233                         if (!initParamNames.equals(recordComponentNames)) {
1234                             log.error(tree, Errors.InvalidCanonicalConstructorInRecord(
1235                                     Fragments.Canonical, env.enclClass.sym.name, Fragments.CanonicalWithNameMismatch));
1236                         }
1237                         if (tree.sym.type.asMethodType().thrown != null && !tree.sym.type.asMethodType().thrown.isEmpty()) {
1238                             log.error(tree,
1239                                     Errors.InvalidCanonicalConstructorInRecord(
1240                                             TreeInfo.isCompactConstructor(tree) ? Fragments.Compact : Fragments.Canonical,
1241                                             env.enclClass.sym.name,
1242                                             Fragments.ThrowsClauseNotAllowedForCanonicalConstructor(
1243                                                     TreeInfo.isCompactConstructor(tree) ? Fragments.Compact : Fragments.Canonical)));
1244                         }
1245                     }
1246                 }
1247 
1248                 // Attribute all type annotations in the body
1249                 annotate.queueScanTreeAndTypeAnnotate(tree.body, localEnv, m, null);
1250                 annotate.flush();
1251 
1252                 // Attribute method body.
1253                 attribStat(tree.body, localEnv);
1254             }
1255 
1256             localEnv.info.scope.leave();
1257             result = tree.type = m.type;
1258         } finally {
1259             chk.setLint(prevLint);
1260             chk.setMethod(prevMethod);
1261         }
1262     }
1263 
1264     public void visitVarDef(JCVariableDecl tree) {
1265         // Local variables have not been entered yet, so we need to do it now:
1266         if (env.info.scope.owner.kind == MTH || env.info.scope.owner.kind == VAR) {
1267             if (tree.sym != null) {
1268                 // parameters have already been entered
1269                 env.info.scope.enter(tree.sym);
1270             } else {
1271                 if (tree.isImplicitlyTyped() && (tree.getModifiers().flags & PARAMETER) == 0) {
1272                     if (tree.init == null) {
1273                         //cannot use 'var' without initializer
1274                         log.error(tree, Errors.CantInferLocalVarType(tree.name, Fragments.LocalMissingInit));
1275                         tree.vartype = make.Erroneous();
1276                     } else {
1277                         Fragment msg = canInferLocalVarType(tree);
1278                         if (msg != null) {
1279                             //cannot use 'var' with initializer which require an explicit target
1280                             //(e.g. lambda, method reference, array initializer).
1281                             log.error(tree, Errors.CantInferLocalVarType(tree.name, msg));
1282                             tree.vartype = make.Erroneous();
1283                         }
1284                     }
1285                 }
1286                 try {
1287                     annotate.blockAnnotations();
1288                     memberEnter.memberEnter(tree, env);
1289                 } finally {
1290                     annotate.unblockAnnotations();
1291                 }
1292             }
1293         } else {
1294             if (tree.init != null) {
1295                 // Field initializer expression need to be entered.
1296                 annotate.queueScanTreeAndTypeAnnotate(tree.init, env, tree.sym, tree.pos());
1297                 annotate.flush();
1298             }
1299         }
1300 
1301         VarSymbol v = tree.sym;
1302         Lint lint = env.info.lint.augment(v);
1303         Lint prevLint = chk.setLint(lint);
1304 
1305         // Check that the variable's declared type is well-formed.
1306         boolean isImplicitLambdaParameter = env.tree.hasTag(LAMBDA) &&
1307                 ((JCLambda)env.tree).paramKind == JCLambda.ParameterKind.IMPLICIT &&
1308                 (tree.sym.flags() & PARAMETER) != 0;
1309         chk.validate(tree.vartype, env, !isImplicitLambdaParameter && !tree.isImplicitlyTyped());
1310 
1311         try {
1312             v.getConstValue(); // ensure compile-time constant initializer is evaluated
1313             deferredLintHandler.flush(tree.pos());
1314             chk.checkDeprecatedAnnotation(tree.pos(), v);
1315 
1316             /* Don't want constant propagation/folding for instance fields of primitive classes,
1317                as these can undergo updates via copy on write.
1318             */
1319             if (tree.init != null) {
1320                 if ((v.flags_field & FINAL) == 0 || ((v.flags_field & STATIC) == 0 && v.owner.isValueClass()) ||
1321                     !memberEnter.needsLazyConstValue(tree.init)) {
1322                     // Not a compile-time constant
1323                     // Attribute initializer in a new environment
1324                     // with the declared variable as owner.
1325                     // Check that initializer conforms to variable's declared type.
1326                     Env<AttrContext> initEnv = memberEnter.initEnv(tree, env);
1327                     initEnv.info.lint = lint;
1328                     // In order to catch self-references, we set the variable's
1329                     // declaration position to maximal possible value, effectively
1330                     // marking the variable as undefined.
1331                     initEnv.info.enclVar = v;
1332                     attribExpr(tree.init, initEnv, v.type);
1333                     if (tree.isImplicitlyTyped()) {
1334                         //fixup local variable type
1335                         v.type = chk.checkLocalVarType(tree, tree.init.type.baseType(), tree.name);
1336                     }
1337                 }
1338                 if (tree.isImplicitlyTyped()) {
1339                     setSyntheticVariableType(tree, v.type);
1340                 }
1341             }
1342             result = tree.type = v.type;
1343             if (env.enclClass.sym.isRecord() && tree.sym.owner.kind == TYP && !v.isStatic()) {
1344                 if (isNonArgsMethodInObject(v.name)) {
1345                     log.error(tree, Errors.IllegalRecordComponentName(v));
1346                 }
1347             }
1348         }
1349         finally {
1350             chk.setLint(prevLint);
1351         }
1352     }
1353 
1354     private boolean isNonArgsMethodInObject(Name name) {
1355         for (Symbol s : syms.objectType.tsym.members().getSymbolsByName(name, s -> s.kind == MTH)) {
1356             if (s.type.getParameterTypes().isEmpty()) {
1357                 return true;
1358             }
1359         }
1360         return false;
1361     }
1362 
1363     Fragment canInferLocalVarType(JCVariableDecl tree) {
1364         LocalInitScanner lis = new LocalInitScanner();
1365         lis.scan(tree.init);
1366         return lis.badInferenceMsg;
1367     }
1368 
1369     static class LocalInitScanner extends TreeScanner {
1370         Fragment badInferenceMsg = null;
1371         boolean needsTarget = true;
1372 
1373         @Override
1374         public void visitNewArray(JCNewArray tree) {
1375             if (tree.elemtype == null && needsTarget) {
1376                 badInferenceMsg = Fragments.LocalArrayMissingTarget;
1377             }
1378         }
1379 
1380         @Override
1381         public void visitLambda(JCLambda tree) {
1382             if (needsTarget) {
1383                 badInferenceMsg = Fragments.LocalLambdaMissingTarget;
1384             }
1385         }
1386 
1387         @Override
1388         public void visitTypeCast(JCTypeCast tree) {
1389             boolean prevNeedsTarget = needsTarget;
1390             try {
1391                 needsTarget = false;
1392                 super.visitTypeCast(tree);
1393             } finally {
1394                 needsTarget = prevNeedsTarget;
1395             }
1396         }
1397 
1398         @Override
1399         public void visitReference(JCMemberReference tree) {
1400             if (needsTarget) {
1401                 badInferenceMsg = Fragments.LocalMrefMissingTarget;
1402             }
1403         }
1404 
1405         @Override
1406         public void visitNewClass(JCNewClass tree) {
1407             boolean prevNeedsTarget = needsTarget;
1408             try {
1409                 needsTarget = false;
1410                 super.visitNewClass(tree);
1411             } finally {
1412                 needsTarget = prevNeedsTarget;
1413             }
1414         }
1415 
1416         @Override
1417         public void visitApply(JCMethodInvocation tree) {
1418             boolean prevNeedsTarget = needsTarget;
1419             try {
1420                 needsTarget = false;
1421                 super.visitApply(tree);
1422             } finally {
1423                 needsTarget = prevNeedsTarget;
1424             }
1425         }
1426     }
1427 
1428     public void visitSkip(JCSkip tree) {
1429         result = null;
1430     }
1431 
1432     public void visitBlock(JCBlock tree) {
1433         if (env.info.scope.owner.kind == TYP || env.info.scope.owner.kind == ERR) {
1434             // Block is a static or instance initializer;
1435             // let the owner of the environment be a freshly
1436             // created BLOCK-method.
1437             Symbol fakeOwner =
1438                 new MethodSymbol(tree.flags | BLOCK |
1439                     env.info.scope.owner.flags() & STRICTFP, names.empty, null,
1440                     env.info.scope.owner);
1441             final Env<AttrContext> localEnv =
1442                 env.dup(tree, env.info.dup(env.info.scope.dupUnshared(fakeOwner)));
1443 
1444             if ((tree.flags & STATIC) != 0) localEnv.info.staticLevel++;
1445             // Attribute all type annotations in the block
1446             annotate.queueScanTreeAndTypeAnnotate(tree, localEnv, localEnv.info.scope.owner, null);
1447             annotate.flush();
1448             attribStats(tree.stats, localEnv);
1449 
1450             {
1451                 // Store init and clinit type annotations with the ClassSymbol
1452                 // to allow output in Gen.normalizeDefs.
1453                 ClassSymbol cs = (ClassSymbol)env.info.scope.owner;
1454                 List<Attribute.TypeCompound> tas = localEnv.info.scope.owner.getRawTypeAttributes();
1455                 if ((tree.flags & STATIC) != 0) {
1456                     cs.appendClassInitTypeAttributes(tas);
1457                 } else {
1458                     cs.appendInitTypeAttributes(tas);
1459                 }
1460             }
1461         } else {
1462             // Create a new local environment with a local scope.
1463             Env<AttrContext> localEnv =
1464                 env.dup(tree, env.info.dup(env.info.scope.dup()));
1465             try {
1466                 attribStats(tree.stats, localEnv);
1467             } finally {
1468                 localEnv.info.scope.leave();
1469             }
1470         }
1471         result = null;
1472     }
1473 
1474     public void visitDoLoop(JCDoWhileLoop tree) {
1475         attribStat(tree.body, env.dup(tree));
1476         attribExpr(tree.cond, env, syms.booleanType);
1477         if (!breaksOutOf(tree, tree.body)) {
1478             //include condition's body when false after the while, if cannot get out of the loop
1479             MatchBindings condBindings = matchBindings;
1480             condBindings.bindingsWhenFalse.forEach(env.info.scope::enter);
1481             condBindings.bindingsWhenFalse.forEach(BindingSymbol::preserveBinding);
1482         }
1483         result = null;
1484     }
1485 
1486     public void visitWhileLoop(JCWhileLoop tree) {
1487         attribExpr(tree.cond, env, syms.booleanType);
1488         MatchBindings condBindings = matchBindings;
1489         // include condition's bindings when true in the body:
1490         Env<AttrContext> whileEnv = bindingEnv(env, condBindings.bindingsWhenTrue);
1491         try {
1492             attribStat(tree.body, whileEnv.dup(tree));
1493         } finally {
1494             whileEnv.info.scope.leave();
1495         }
1496         if (!breaksOutOf(tree, tree.body)) {
1497             //include condition's bindings when false after the while, if cannot get out of the loop
1498             condBindings.bindingsWhenFalse.forEach(env.info.scope::enter);
1499             condBindings.bindingsWhenFalse.forEach(BindingSymbol::preserveBinding);
1500         }
1501         result = null;
1502     }
1503 
1504     private boolean breaksOutOf(JCTree loop, JCTree body) {
1505         preFlow(body);
1506         return flow.breaksOutOf(env, loop, body, make);
1507     }
1508 
1509     public void visitForLoop(JCForLoop tree) {
1510         Env<AttrContext> loopEnv =
1511             env.dup(env.tree, env.info.dup(env.info.scope.dup()));
1512         MatchBindings condBindings = MatchBindingsComputer.EMPTY;
1513         try {
1514             attribStats(tree.init, loopEnv);
1515             if (tree.cond != null) {
1516                 attribExpr(tree.cond, loopEnv, syms.booleanType);
1517                 // include condition's bindings when true in the body and step:
1518                 condBindings = matchBindings;
1519             }
1520             Env<AttrContext> bodyEnv = bindingEnv(loopEnv, condBindings.bindingsWhenTrue);
1521             try {
1522                 bodyEnv.tree = tree; // before, we were not in loop!
1523                 attribStats(tree.step, bodyEnv);
1524                 attribStat(tree.body, bodyEnv);
1525             } finally {
1526                 bodyEnv.info.scope.leave();
1527             }
1528             result = null;
1529         }
1530         finally {
1531             loopEnv.info.scope.leave();
1532         }
1533         if (!breaksOutOf(tree, tree.body)) {
1534             //include condition's body when false after the while, if cannot get out of the loop
1535             condBindings.bindingsWhenFalse.forEach(env.info.scope::enter);
1536             condBindings.bindingsWhenFalse.forEach(BindingSymbol::preserveBinding);
1537         }
1538     }
1539 
1540     public void visitForeachLoop(JCEnhancedForLoop tree) {
1541         Env<AttrContext> loopEnv =
1542             env.dup(env.tree, env.info.dup(env.info.scope.dup()));
1543         try {
1544             //the Formal Parameter of a for-each loop is not in the scope when
1545             //attributing the for-each expression; we mimic this by attributing
1546             //the for-each expression first (against original scope).
1547             Type exprType = types.cvarUpperBound(attribExpr(tree.expr, loopEnv));
1548             chk.checkNonVoid(tree.pos(), exprType);
1549             Type elemtype = types.elemtype(exprType); // perhaps expr is an array?
1550             if (elemtype == null) {
1551                 // or perhaps expr implements Iterable<T>?
1552                 Type base = types.asSuper(exprType.referenceProjectionOrSelf(), syms.iterableType.tsym);
1553                 if (base == null) {
1554                     log.error(tree.expr.pos(),
1555                               Errors.ForeachNotApplicableToType(exprType,
1556                                                                 Fragments.TypeReqArrayOrIterable));
1557                     elemtype = types.createErrorType(exprType);
1558                 } else {
1559                     List<Type> iterableParams = base.allparams();
1560                     elemtype = iterableParams.isEmpty()
1561                         ? syms.objectType
1562                         : types.wildUpperBound(iterableParams.head);
1563 
1564                     // Check the return type of the method iterator().
1565                     // This is the bare minimum we need to verify to make sure code generation doesn't crash.
1566                     Symbol iterSymbol = rs.resolveInternalMethod(tree.pos(),
1567                             loopEnv, types.skipTypeVars(exprType, false), names.iterator, List.nil(), List.nil());
1568                     if (types.asSuper(iterSymbol.type.getReturnType().referenceProjectionOrSelf(), syms.iteratorType.tsym) == null) {
1569                         log.error(tree.pos(),
1570                                 Errors.ForeachNotApplicableToType(exprType, Fragments.TypeReqArrayOrIterable));
1571                     }
1572                 }
1573             }
1574             if (tree.var.isImplicitlyTyped()) {
1575                 Type inferredType = chk.checkLocalVarType(tree.var, elemtype, tree.var.name);
1576                 setSyntheticVariableType(tree.var, inferredType);
1577             }
1578             attribStat(tree.var, loopEnv);
1579             chk.checkType(tree.expr.pos(), elemtype, tree.var.sym.type);
1580             loopEnv.tree = tree; // before, we were not in loop!
1581             attribStat(tree.body, loopEnv);
1582             result = null;
1583         }
1584         finally {
1585             loopEnv.info.scope.leave();
1586         }
1587     }
1588 
1589     public void visitLabelled(JCLabeledStatement tree) {
1590         // Check that label is not used in an enclosing statement
1591         Env<AttrContext> env1 = env;
1592         while (env1 != null && !env1.tree.hasTag(CLASSDEF)) {
1593             if (env1.tree.hasTag(LABELLED) &&
1594                 ((JCLabeledStatement) env1.tree).label == tree.label) {
1595                 log.error(tree.pos(),
1596                           Errors.LabelAlreadyInUse(tree.label));
1597                 break;
1598             }
1599             env1 = env1.next;
1600         }
1601 
1602         attribStat(tree.body, env.dup(tree));
1603         result = null;
1604     }
1605 
1606     public void visitSwitch(JCSwitch tree) {
1607         handleSwitch(tree, tree.selector, tree.cases, (c, caseEnv) -> {
1608             attribStats(c.stats, caseEnv);
1609         });
1610         result = null;
1611     }
1612 
1613     public void visitSwitchExpression(JCSwitchExpression tree) {
1614         tree.polyKind = (pt().hasTag(NONE) && pt() != Type.recoveryType && pt() != Infer.anyPoly) ?
1615                 PolyKind.STANDALONE : PolyKind.POLY;
1616 
1617         if (tree.polyKind == PolyKind.POLY && resultInfo.pt.hasTag(VOID)) {
1618             //this means we are returning a poly conditional from void-compatible lambda expression
1619             resultInfo.checkContext.report(tree, diags.fragment(Fragments.SwitchExpressionTargetCantBeVoid));
1620             result = tree.type = types.createErrorType(resultInfo.pt);
1621             return;
1622         }
1623 
1624         ResultInfo condInfo = tree.polyKind == PolyKind.STANDALONE ?
1625                 unknownExprInfo :
1626                 resultInfo.dup(switchExpressionContext(resultInfo.checkContext));
1627 
1628         ListBuffer<DiagnosticPosition> caseTypePositions = new ListBuffer<>();
1629         ListBuffer<Type> caseTypes = new ListBuffer<>();
1630 
1631         handleSwitch(tree, tree.selector, tree.cases, (c, caseEnv) -> {
1632             caseEnv.info.yieldResult = condInfo;
1633             attribStats(c.stats, caseEnv);
1634             new TreeScanner() {
1635                 @Override
1636                 public void visitYield(JCYield brk) {
1637                     if (brk.target == tree) {
1638                         caseTypePositions.append(brk.value != null ? brk.value.pos() : brk.pos());
1639                         caseTypes.append(brk.value != null ? brk.value.type : syms.errType);
1640                     }
1641                     super.visitYield(brk);
1642                 }
1643 
1644                 @Override public void visitClassDef(JCClassDecl tree) {}
1645                 @Override public void visitLambda(JCLambda tree) {}
1646             }.scan(c.stats);
1647         });
1648 
1649         if (tree.cases.isEmpty()) {
1650             log.error(tree.pos(),
1651                       Errors.SwitchExpressionEmpty);
1652         } else if (caseTypes.isEmpty()) {
1653             log.error(tree.pos(),
1654                       Errors.SwitchExpressionNoResultExpressions);
1655         }
1656 
1657         Type owntype = (tree.polyKind == PolyKind.STANDALONE) ? condType(caseTypePositions.toList(), caseTypes.toList()) : pt();
1658 
1659         result = tree.type = check(tree, owntype, KindSelector.VAL, resultInfo);
1660     }
1661     //where:
1662         CheckContext switchExpressionContext(CheckContext checkContext) {
1663             return new Check.NestedCheckContext(checkContext) {
1664                 //this will use enclosing check context to check compatibility of
1665                 //subexpression against target type; if we are in a method check context,
1666                 //depending on whether boxing is allowed, we could have incompatibilities
1667                 @Override
1668                 public void report(DiagnosticPosition pos, JCDiagnostic details) {
1669                     enclosingContext.report(pos, diags.fragment(Fragments.IncompatibleTypeInSwitchExpression(details)));
1670                 }
1671             };
1672         }
1673 
1674     private void handleSwitch(JCTree switchTree,
1675                               JCExpression selector,
1676                               List<JCCase> cases,
1677                               BiConsumer<JCCase, Env<AttrContext>> attribCase) {
1678         Type seltype = attribExpr(selector, env);
1679 
1680         Env<AttrContext> switchEnv =
1681             env.dup(switchTree, env.info.dup(env.info.scope.dup()));
1682 
1683         try {
1684             boolean enumSwitch = (seltype.tsym.flags() & Flags.ENUM) != 0;
1685             boolean stringSwitch = types.isSameType(seltype, syms.stringType);
1686             boolean errorEnumSwitch = TreeInfo.isErrorEnumSwitch(selector, cases);
1687             boolean patternSwitch;
1688             if (!enumSwitch && !stringSwitch && !errorEnumSwitch &&
1689                 !types.isAssignable(seltype, syms.intType)) {
1690                 preview.checkSourceLevel(selector.pos(), Feature.PATTERN_SWITCH);
1691                 patternSwitch = true;
1692             } else {
1693                 patternSwitch = cases.stream()
1694                                      .flatMap(c -> c.labels.stream())
1695                                      .anyMatch(l -> l.isPattern());
1696             }
1697 
1698             // Attribute all cases and
1699             // check that there are no duplicate case labels or default clauses.
1700             Set<Object> labels = new HashSet<>(); // The set of case labels.
1701             List<Type> coveredTypesForPatterns = List.nil();
1702             List<Type> coveredTypesForConstants = List.nil();
1703             boolean hasDefault = false;           // Is there a default label?
1704             boolean hasTotalPattern = false;      // Is there a total pattern?
1705             boolean hasNullPattern = false;       // Is there a null pattern?
1706             CaseTree.CaseKind caseKind = null;
1707             boolean wasError = false;
1708             MatchBindings prevBindings = null;
1709             for (List<JCCase> l = cases; l.nonEmpty(); l = l.tail) {
1710                 JCCase c = l.head;
1711                 if (caseKind == null) {
1712                     caseKind = c.caseKind;
1713                 } else if (caseKind != c.caseKind && !wasError) {
1714                     log.error(c.pos(),
1715                               Errors.SwitchMixingCaseTypes);
1716                     wasError = true;
1717                 }
1718                 MatchBindings currentBindings = prevBindings;
1719                 boolean wasTotalPattern = hasTotalPattern;
1720                 for (JCCaseLabel pat : c.labels) {
1721                     if (pat.isExpression()) {
1722                         JCExpression expr = (JCExpression) pat;
1723                         if (TreeInfo.isNull(expr)) {
1724                             preview.checkSourceLevel(expr.pos(), Feature.CASE_NULL);
1725                             if (hasNullPattern) {
1726                                 log.error(pat.pos(), Errors.DuplicateCaseLabel);
1727                             } else if (wasTotalPattern) {
1728                                 log.error(pat.pos(), Errors.PatternDominated);
1729                             }
1730                             hasNullPattern = true;
1731                             attribExpr(expr, switchEnv, seltype);
1732                             matchBindings = new MatchBindings(matchBindings.bindingsWhenTrue, matchBindings.bindingsWhenFalse, true);
1733                         } else if (enumSwitch) {
1734                             Symbol sym = enumConstant(expr, seltype);
1735                             if (sym == null) {
1736                                 log.error(expr.pos(), Errors.EnumLabelMustBeUnqualifiedEnum);
1737                             } else if (!labels.add(sym)) {
1738                                 log.error(pat.pos(), Errors.DuplicateCaseLabel);
1739                             } else {
1740                                 checkCaseLabelDominated(pat.pos(), coveredTypesForConstants, sym.type);
1741                             }
1742                         } else if (errorEnumSwitch) {
1743                             //error recovery: the selector is erroneous, and all the case labels
1744                             //are identifiers. This could be an enum switch - don't report resolve
1745                             //error for the case label:
1746                             var prevResolveHelper = rs.basicLogResolveHelper;
1747                             try {
1748                                 rs.basicLogResolveHelper = rs.silentLogResolveHelper;
1749                                 attribExpr(pat, switchEnv, seltype);
1750                             } finally {
1751                                 rs.basicLogResolveHelper = prevResolveHelper;
1752                             }
1753                         } else {
1754                             ResultInfo valTypInfo = new ResultInfo(KindSelector.VAL_TYP,
1755                                                                    !seltype.hasTag(ERROR) ? seltype
1756                                                                                           : Type.noType);
1757                             Type pattype = attribTree(expr, switchEnv, valTypInfo);
1758                             if (!pattype.hasTag(ERROR)) {
1759                                 if (pattype.constValue() == null) {
1760                                     Symbol s = TreeInfo.symbol(expr);
1761                                     if (s != null && s.kind == TYP && allowPatternSwitch) {
1762                                         log.error(expr.pos(),
1763                                                   Errors.PatternExpected);
1764                                     } else {
1765                                         log.error(expr.pos(),
1766                                                   (stringSwitch ? Errors.StringConstReq : Errors.ConstExprReq));
1767                                     }
1768                                 } else if (!stringSwitch && !types.isAssignable(seltype, syms.intType)) {
1769                                     log.error(pat.pos(), Errors.ConstantLabelNotCompatible(pattype, seltype));
1770                                 } else if (!labels.add(pattype.constValue())) {
1771                                     log.error(c.pos(), Errors.DuplicateCaseLabel);
1772                                 } else {
1773                                     checkCaseLabelDominated(pat.pos(), coveredTypesForConstants, types.boxedTypeOrType(pattype));
1774                                 }
1775                             }
1776                         }
1777                     } else if (pat.hasTag(DEFAULTCASELABEL)) {
1778                         if (hasDefault) {
1779                             log.error(pat.pos(), Errors.DuplicateDefaultLabel);
1780                         } else if (hasTotalPattern) {
1781                             log.error(pat.pos(), Errors.TotalPatternAndDefault);
1782                         }
1783                         hasDefault = true;
1784                         matchBindings = MatchBindingsComputer.EMPTY;
1785                     } else {
1786                         //binding pattern
1787                         attribExpr(pat, switchEnv);
1788                         var primary = TreeInfo.primaryPatternType((JCPattern) pat);
1789                         Type primaryType = primary.type();
1790                         if (!primaryType.hasTag(TYPEVAR)) {
1791                             primaryType = chk.checkClassOrArrayType(pat.pos(), primaryType);
1792                         }
1793                         checkCastablePattern(pat.pos(), seltype, primaryType);
1794                         Type patternType = types.erasure(primaryType);
1795                         boolean isTotal = primary.unconditional() &&
1796                                           !patternType.isErroneous() &&
1797                                           types.isSubtype(types.erasure(seltype), patternType);
1798                         if (isTotal) {
1799                             if (hasTotalPattern) {
1800                                 log.error(pat.pos(), Errors.DuplicateTotalPattern);
1801                             } else if (hasDefault) {
1802                                 log.error(pat.pos(), Errors.TotalPatternAndDefault);
1803                             }
1804                             hasTotalPattern = true;
1805                         }
1806                         checkCaseLabelDominated(pat.pos(), coveredTypesForPatterns, patternType);
1807                         if (!patternType.isErroneous()) {
1808                             coveredTypesForConstants = coveredTypesForConstants.prepend(patternType);
1809                             if (primary.unconditional()) {
1810                                 coveredTypesForPatterns = coveredTypesForPatterns.prepend(patternType);
1811                             }
1812                         }
1813                     }
1814                     currentBindings = matchBindingsComputer.switchCase(pat, currentBindings, matchBindings);
1815                 }
1816                 Env<AttrContext> caseEnv =
1817                         bindingEnv(switchEnv, c, currentBindings.bindingsWhenTrue);
1818                 try {
1819                     attribCase.accept(c, caseEnv);
1820                 } finally {
1821                     caseEnv.info.scope.leave();
1822                 }
1823                 addVars(c.stats, switchEnv.info.scope);
1824 
1825                 preFlow(c);
1826                 c.completesNormally = flow.aliveAfter(caseEnv, c, make);
1827 
1828                 prevBindings = c.caseKind == CaseTree.CaseKind.STATEMENT && c.completesNormally ? currentBindings
1829                                                                                                 : null;
1830             }
1831             if (patternSwitch) {
1832                 chk.checkSwitchCaseStructure(cases);
1833             }
1834             if (switchTree.hasTag(SWITCH)) {
1835                 ((JCSwitch) switchTree).hasTotalPattern = hasDefault || hasTotalPattern;
1836                 ((JCSwitch) switchTree).patternSwitch = patternSwitch;
1837             } else if (switchTree.hasTag(SWITCH_EXPRESSION)) {
1838                 ((JCSwitchExpression) switchTree).hasTotalPattern = hasDefault || hasTotalPattern;
1839                 ((JCSwitchExpression) switchTree).patternSwitch = patternSwitch;
1840             } else {
1841                 Assert.error(switchTree.getTag().name());
1842             }
1843         } finally {
1844             switchEnv.info.scope.leave();
1845         }
1846     }
1847     // where
1848         /** Add any variables defined in stats to the switch scope. */
1849         private static void addVars(List<JCStatement> stats, WriteableScope switchScope) {
1850             for (;stats.nonEmpty(); stats = stats.tail) {
1851                 JCTree stat = stats.head;
1852                 if (stat.hasTag(VARDEF))
1853                     switchScope.enter(((JCVariableDecl) stat).sym);
1854             }
1855         }
1856         private void checkCaseLabelDominated(DiagnosticPosition pos,
1857                                              List<Type> coveredTypes, Type patternType) {
1858             for (Type existing : coveredTypes) {
1859                 if (types.isSubtype(patternType, existing)) {
1860                     log.error(pos, Errors.PatternDominated);
1861                 }
1862             }
1863         }
1864     // where
1865     /** Return the selected enumeration constant symbol, or null. */
1866     private Symbol enumConstant(JCTree tree, Type enumType) {
1867         if (tree.hasTag(IDENT)) {
1868             JCIdent ident = (JCIdent)tree;
1869             Name name = ident.name;
1870             for (Symbol sym : enumType.tsym.members().getSymbolsByName(name)) {
1871                 if (sym.kind == VAR) {
1872                     Symbol s = ident.sym = sym;
1873                     ((VarSymbol)s).getConstValue(); // ensure initializer is evaluated
1874                     ident.type = s.type;
1875                     return ((s.flags_field & Flags.ENUM) == 0)
1876                         ? null : s;
1877                 }
1878             }
1879         }
1880         return null;
1881     }
1882 
1883     public void visitSynchronized(JCSynchronized tree) {
1884         chk.checkIdentityType(tree.pos(), attribExpr(tree.lock, env));
1885         if (env.info.lint.isEnabled(LintCategory.SYNCHRONIZATION) && isValueBased(tree.lock.type)) {
1886             log.warning(LintCategory.SYNCHRONIZATION, tree.pos(), Warnings.AttemptToSynchronizeOnInstanceOfValueBasedClass);
1887         }
1888         attribStat(tree.body, env);
1889         result = null;
1890     }
1891         // where
1892         private boolean isValueBased(Type t) {
1893             return t != null && t.tsym != null && (t.tsym.flags() & VALUE_BASED) != 0;
1894         }
1895 
1896 
1897     public void visitTry(JCTry tree) {
1898         // Create a new local environment with a local
1899         Env<AttrContext> localEnv = env.dup(tree, env.info.dup(env.info.scope.dup()));
1900         try {
1901             boolean isTryWithResource = tree.resources.nonEmpty();
1902             // Create a nested environment for attributing the try block if needed
1903             Env<AttrContext> tryEnv = isTryWithResource ?
1904                 env.dup(tree, localEnv.info.dup(localEnv.info.scope.dup())) :
1905                 localEnv;
1906             try {
1907                 // Attribute resource declarations
1908                 for (JCTree resource : tree.resources) {
1909                     CheckContext twrContext = new Check.NestedCheckContext(resultInfo.checkContext) {
1910                         @Override
1911                         public void report(DiagnosticPosition pos, JCDiagnostic details) {
1912                             chk.basicHandler.report(pos, diags.fragment(Fragments.TryNotApplicableToType(details)));
1913                         }
1914                     };
1915                     ResultInfo twrResult =
1916                         new ResultInfo(KindSelector.VAR,
1917                                        syms.autoCloseableType,
1918                                        twrContext);
1919                     if (resource.hasTag(VARDEF)) {
1920                         attribStat(resource, tryEnv);
1921                         twrResult.check(resource, resource.type);
1922 
1923                         //check that resource type cannot throw InterruptedException
1924                         checkAutoCloseable(resource.pos(), localEnv, resource.type);
1925 
1926                         VarSymbol var = ((JCVariableDecl) resource).sym;
1927                         var.setData(ElementKind.RESOURCE_VARIABLE);
1928                     } else {
1929                         attribTree(resource, tryEnv, twrResult);
1930                     }
1931                 }
1932                 // Attribute body
1933                 attribStat(tree.body, tryEnv);
1934             } finally {
1935                 if (isTryWithResource)
1936                     tryEnv.info.scope.leave();
1937             }
1938 
1939             // Attribute catch clauses
1940             for (List<JCCatch> l = tree.catchers; l.nonEmpty(); l = l.tail) {
1941                 JCCatch c = l.head;
1942                 Env<AttrContext> catchEnv =
1943                     localEnv.dup(c, localEnv.info.dup(localEnv.info.scope.dup()));
1944                 try {
1945                     Type ctype = attribStat(c.param, catchEnv);
1946                     if (TreeInfo.isMultiCatch(c)) {
1947                         //multi-catch parameter is implicitly marked as final
1948                         c.param.sym.flags_field |= FINAL | UNION;
1949                     }
1950                     if (c.param.sym.kind == VAR) {
1951                         c.param.sym.setData(ElementKind.EXCEPTION_PARAMETER);
1952                     }
1953                     chk.checkType(c.param.vartype.pos(),
1954                                   chk.checkClassType(c.param.vartype.pos(), ctype),
1955                                   syms.throwableType);
1956                     attribStat(c.body, catchEnv);
1957                 } finally {
1958                     catchEnv.info.scope.leave();
1959                 }
1960             }
1961 
1962             // Attribute finalizer
1963             if (tree.finalizer != null) attribStat(tree.finalizer, localEnv);
1964             result = null;
1965         }
1966         finally {
1967             localEnv.info.scope.leave();
1968         }
1969     }
1970 
1971     void checkAutoCloseable(DiagnosticPosition pos, Env<AttrContext> env, Type resource) {
1972         if (!resource.isErroneous() &&
1973             types.asSuper(resource.referenceProjectionOrSelf(), syms.autoCloseableType.tsym) != null &&
1974             !types.isSameType(resource, syms.autoCloseableType)) { // Don't emit warning for AutoCloseable itself
1975             Symbol close = syms.noSymbol;
1976             Log.DiagnosticHandler discardHandler = new Log.DiscardDiagnosticHandler(log);
1977             try {
1978                 close = rs.resolveQualifiedMethod(pos,
1979                         env,
1980                         types.skipTypeVars(resource, false),
1981                         names.close,
1982                         List.nil(),
1983                         List.nil());
1984             }
1985             finally {
1986                 log.popDiagnosticHandler(discardHandler);
1987             }
1988             if (close.kind == MTH &&
1989                     close.overrides(syms.autoCloseableClose, resource.tsym, types, true) &&
1990                     chk.isHandled(syms.interruptedExceptionType, types.memberType(resource, close).getThrownTypes()) &&
1991                     env.info.lint.isEnabled(LintCategory.TRY)) {
1992                 log.warning(LintCategory.TRY, pos, Warnings.TryResourceThrowsInterruptedExc(resource));
1993             }
1994         }
1995     }
1996 
1997     public void visitConditional(JCConditional tree) {
1998         Type condtype = attribExpr(tree.cond, env, syms.booleanType);
1999         MatchBindings condBindings = matchBindings;
2000 
2001         tree.polyKind = (!allowPoly ||
2002                 pt().hasTag(NONE) && pt() != Type.recoveryType && pt() != Infer.anyPoly ||
2003                 isBooleanOrNumeric(env, tree)) ?
2004                 PolyKind.STANDALONE : PolyKind.POLY;
2005 
2006         if (tree.polyKind == PolyKind.POLY && resultInfo.pt.hasTag(VOID)) {
2007             //this means we are returning a poly conditional from void-compatible lambda expression
2008             resultInfo.checkContext.report(tree, diags.fragment(Fragments.ConditionalTargetCantBeVoid));
2009             result = tree.type = types.createErrorType(resultInfo.pt);
2010             return;
2011         }
2012 
2013         ResultInfo condInfo = tree.polyKind == PolyKind.STANDALONE ?
2014                 unknownExprInfo :
2015                 resultInfo.dup(conditionalContext(resultInfo.checkContext));
2016 
2017 
2018         // x ? y : z
2019         // include x's bindings when true in y
2020         // include x's bindings when false in z
2021 
2022         Type truetype;
2023         Env<AttrContext> trueEnv = bindingEnv(env, condBindings.bindingsWhenTrue);
2024         try {
2025             truetype = attribTree(tree.truepart, trueEnv, condInfo);
2026         } finally {
2027             trueEnv.info.scope.leave();
2028         }
2029 
2030         MatchBindings trueBindings = matchBindings;
2031 
2032         Type falsetype;
2033         Env<AttrContext> falseEnv = bindingEnv(env, condBindings.bindingsWhenFalse);
2034         try {
2035             falsetype = attribTree(tree.falsepart, falseEnv, condInfo);
2036         } finally {
2037             falseEnv.info.scope.leave();
2038         }
2039 
2040         MatchBindings falseBindings = matchBindings;
2041 
2042         Type owntype = (tree.polyKind == PolyKind.STANDALONE) ?
2043                 condType(List.of(tree.truepart.pos(), tree.falsepart.pos()),
2044                          List.of(truetype, falsetype)) : pt();
2045         if (condtype.constValue() != null &&
2046                 truetype.constValue() != null &&
2047                 falsetype.constValue() != null &&
2048                 !owntype.hasTag(NONE)) {
2049             //constant folding
2050             owntype = cfolder.coerce(condtype.isTrue() ? truetype : falsetype, owntype);
2051         }
2052         result = check(tree, owntype, KindSelector.VAL, resultInfo);
2053         matchBindings = matchBindingsComputer.conditional(tree, condBindings, trueBindings, falseBindings);
2054     }
2055     //where
2056         private boolean isBooleanOrNumeric(Env<AttrContext> env, JCExpression tree) {
2057             switch (tree.getTag()) {
2058                 case LITERAL: return ((JCLiteral)tree).typetag.isSubRangeOf(DOUBLE) ||
2059                               ((JCLiteral)tree).typetag == BOOLEAN ||
2060                               ((JCLiteral)tree).typetag == BOT;
2061                 case LAMBDA: case REFERENCE: return false;
2062                 case PARENS: return isBooleanOrNumeric(env, ((JCParens)tree).expr);
2063                 case CONDEXPR:
2064                     JCConditional condTree = (JCConditional)tree;
2065                     return isBooleanOrNumeric(env, condTree.truepart) &&
2066                             isBooleanOrNumeric(env, condTree.falsepart);
2067                 case APPLY:
2068                     JCMethodInvocation speculativeMethodTree =
2069                             (JCMethodInvocation)deferredAttr.attribSpeculative(
2070                                     tree, env, unknownExprInfo,
2071                                     argumentAttr.withLocalCacheContext());
2072                     Symbol msym = TreeInfo.symbol(speculativeMethodTree.meth);
2073                     Type receiverType = speculativeMethodTree.meth.hasTag(IDENT) ?
2074                             env.enclClass.type :
2075                             ((JCFieldAccess)speculativeMethodTree.meth).selected.type;
2076                     Type owntype = types.memberType(receiverType, msym).getReturnType();
2077                     return primitiveOrBoxed(owntype);
2078                 case NEWCLASS:
2079                     JCExpression className =
2080                             removeClassParams.translate(((JCNewClass)tree).clazz);
2081                     JCExpression speculativeNewClassTree =
2082                             (JCExpression)deferredAttr.attribSpeculative(
2083                                     className, env, unknownTypeInfo,
2084                                     argumentAttr.withLocalCacheContext());
2085                     return primitiveOrBoxed(speculativeNewClassTree.type);
2086                 default:
2087                     Type speculativeType = deferredAttr.attribSpeculative(tree, env, unknownExprInfo,
2088                             argumentAttr.withLocalCacheContext()).type;
2089                     return primitiveOrBoxed(speculativeType);
2090             }
2091         }
2092         //where
2093             boolean primitiveOrBoxed(Type t) {
2094                 return (!t.hasTag(TYPEVAR) && !t.isErroneous() && types.unboxedTypeOrType(t).isPrimitive());
2095             }
2096 
2097             TreeTranslator removeClassParams = new TreeTranslator() {
2098                 @Override
2099                 public void visitTypeApply(JCTypeApply tree) {
2100                     result = translate(tree.clazz);
2101                 }
2102             };
2103 
2104         CheckContext conditionalContext(CheckContext checkContext) {
2105             return new Check.NestedCheckContext(checkContext) {
2106                 //this will use enclosing check context to check compatibility of
2107                 //subexpression against target type; if we are in a method check context,
2108                 //depending on whether boxing is allowed, we could have incompatibilities
2109                 @Override
2110                 public void report(DiagnosticPosition pos, JCDiagnostic details) {
2111                     enclosingContext.report(pos, diags.fragment(Fragments.IncompatibleTypeInConditional(details)));
2112                 }
2113             };
2114         }
2115 
2116         /** Compute the type of a conditional expression, after
2117          *  checking that it exists.  See JLS 15.25. Does not take into
2118          *  account the special case where condition and both arms
2119          *  are constants.
2120          *
2121          *  @param pos      The source position to be used for error
2122          *                  diagnostics.
2123          *  @param thentype The type of the expression's then-part.
2124          *  @param elsetype The type of the expression's else-part.
2125          */
2126         Type condType(List<DiagnosticPosition> positions, List<Type> condTypes) {
2127             if (condTypes.isEmpty()) {
2128                 return syms.objectType; //TODO: how to handle?
2129             }
2130             Type first = condTypes.head;
2131             // If same type, that is the result
2132             if (condTypes.tail.stream().allMatch(t -> types.isSameType(first, t)))
2133                 return first.baseType();
2134 
2135             List<Type> unboxedTypes = condTypes.stream()
2136                                                .map(t -> t.isPrimitive() ? t : types.unboxedType(t))
2137                                                .collect(List.collector());
2138 
2139             // Otherwise, if both arms can be converted to a numeric
2140             // type, return the least numeric type that fits both arms
2141             // (i.e. return larger of the two, or return int if one
2142             // arm is short, the other is char).
2143             if (unboxedTypes.stream().allMatch(t -> t.isPrimitive())) {
2144                 // If one arm has an integer subrange type (i.e., byte,
2145                 // short, or char), and the other is an integer constant
2146                 // that fits into the subrange, return the subrange type.
2147                 for (Type type : unboxedTypes) {
2148                     if (!type.getTag().isStrictSubRangeOf(INT)) {
2149                         continue;
2150                     }
2151                     if (unboxedTypes.stream().filter(t -> t != type).allMatch(t -> t.hasTag(INT) && types.isAssignable(t, type)))
2152                         return type.baseType();
2153                 }
2154 
2155                 for (TypeTag tag : primitiveTags) {
2156                     Type candidate = syms.typeOfTag[tag.ordinal()];
2157                     if (unboxedTypes.stream().allMatch(t -> types.isSubtype(t, candidate))) {
2158                         return candidate;
2159                     }
2160                 }
2161             }
2162 
2163             // Those were all the cases that could result in a primitive. See if primitive boxing and primitive
2164             // value conversions bring about a convergence.
2165             condTypes = condTypes.stream()
2166                                  .map(t -> t.isPrimitive() ? types.boxedClass(t).type
2167                                          : t.isReferenceProjection() ? t.valueProjection() : t)
2168                                  .collect(List.collector());
2169 
2170             for (Type type : condTypes) {
2171                 if (condTypes.stream().filter(t -> t != type).allMatch(t -> types.isAssignable(t, type)))
2172                     return type.baseType();
2173             }
2174 
2175             Iterator<DiagnosticPosition> posIt = positions.iterator();
2176 
2177             condTypes = condTypes.stream()
2178                                  .map(t -> chk.checkNonVoid(posIt.next(), t.isPrimitiveClass() ? t.referenceProjection() : t))
2179                                  .collect(List.collector());
2180 
2181             // both are known to be reference types (or projections).  The result is
2182             // lub(thentype,elsetype). This cannot fail, as it will
2183             // always be possible to infer "Object" if nothing better.
2184             return types.lub(condTypes.stream()
2185                         .map(t -> t.baseType())
2186                         .filter(t -> !t.hasTag(BOT))
2187                         .collect(List.collector()));
2188         }
2189 
2190     static final TypeTag[] primitiveTags = new TypeTag[]{
2191         BYTE,
2192         CHAR,
2193         SHORT,
2194         INT,
2195         LONG,
2196         FLOAT,
2197         DOUBLE,
2198         BOOLEAN,
2199     };
2200 
2201     Env<AttrContext> bindingEnv(Env<AttrContext> env, List<BindingSymbol> bindings) {
2202         return bindingEnv(env, env.tree, bindings);
2203     }
2204 
2205     Env<AttrContext> bindingEnv(Env<AttrContext> env, JCTree newTree, List<BindingSymbol> bindings) {
2206         Env<AttrContext> env1 = env.dup(newTree, env.info.dup(env.info.scope.dup()));
2207         bindings.forEach(env1.info.scope::enter);
2208         return env1;
2209     }
2210 
2211     public void visitIf(JCIf tree) {
2212         attribExpr(tree.cond, env, syms.booleanType);
2213 
2214         // if (x) { y } [ else z ]
2215         // include x's bindings when true in y
2216         // include x's bindings when false in z
2217 
2218         MatchBindings condBindings = matchBindings;
2219         Env<AttrContext> thenEnv = bindingEnv(env, condBindings.bindingsWhenTrue);
2220 
2221         try {
2222             attribStat(tree.thenpart, thenEnv);
2223         } finally {
2224             thenEnv.info.scope.leave();
2225         }
2226 
2227         preFlow(tree.thenpart);
2228         boolean aliveAfterThen = flow.aliveAfter(env, tree.thenpart, make);
2229         boolean aliveAfterElse;
2230 
2231         if (tree.elsepart != null) {
2232             Env<AttrContext> elseEnv = bindingEnv(env, condBindings.bindingsWhenFalse);
2233             try {
2234                 attribStat(tree.elsepart, elseEnv);
2235             } finally {
2236                 elseEnv.info.scope.leave();
2237             }
2238             preFlow(tree.elsepart);
2239             aliveAfterElse = flow.aliveAfter(env, tree.elsepart, make);
2240         } else {
2241             aliveAfterElse = true;
2242         }
2243 
2244         chk.checkEmptyIf(tree);
2245 
2246         List<BindingSymbol> afterIfBindings = List.nil();
2247 
2248         if (aliveAfterThen && !aliveAfterElse) {
2249             afterIfBindings = condBindings.bindingsWhenTrue;
2250         } else if (aliveAfterElse && !aliveAfterThen) {
2251             afterIfBindings = condBindings.bindingsWhenFalse;
2252         }
2253 
2254         afterIfBindings.forEach(env.info.scope::enter);
2255         afterIfBindings.forEach(BindingSymbol::preserveBinding);
2256 
2257         result = null;
2258     }
2259 
2260         void preFlow(JCTree tree) {
2261             attrRecover.doRecovery();
2262             new PostAttrAnalyzer() {
2263                 @Override
2264                 public void scan(JCTree tree) {
2265                     if (tree == null ||
2266                             (tree.type != null &&
2267                             tree.type == Type.stuckType)) {
2268                         //don't touch stuck expressions!
2269                         return;
2270                     }
2271                     super.scan(tree);
2272                 }
2273 
2274                 @Override
2275                 public void visitClassDef(JCClassDecl that) {
2276                     if (that.sym != null) {
2277                         // Method preFlow shouldn't visit class definitions
2278                         // that have not been entered and attributed.
2279                         // See JDK-8254557 and JDK-8203277 for more details.
2280                         super.visitClassDef(that);
2281                     }
2282                 }
2283 
2284                 @Override
2285                 public void visitLambda(JCLambda that) {
2286                     if (that.type != null) {
2287                         // Method preFlow shouldn't visit lambda expressions
2288                         // that have not been entered and attributed.
2289                         // See JDK-8254557 and JDK-8203277 for more details.
2290                         super.visitLambda(that);
2291                     }
2292                 }
2293             }.scan(tree);
2294         }
2295 
2296     public void visitExec(JCExpressionStatement tree) {
2297         //a fresh environment is required for 292 inference to work properly ---
2298         //see Infer.instantiatePolymorphicSignatureInstance()
2299         Env<AttrContext> localEnv = env.dup(tree);
2300         attribExpr(tree.expr, localEnv);
2301         result = null;
2302     }
2303 
2304     public void visitBreak(JCBreak tree) {
2305         tree.target = findJumpTarget(tree.pos(), tree.getTag(), tree.label, env);
2306         result = null;
2307     }
2308 
2309     public void visitYield(JCYield tree) {
2310         if (env.info.yieldResult != null) {
2311             attribTree(tree.value, env, env.info.yieldResult);
2312             tree.target = findJumpTarget(tree.pos(), tree.getTag(), names.empty, env);
2313         } else {
2314             log.error(tree.pos(), tree.value.hasTag(PARENS)
2315                     ? Errors.NoSwitchExpressionQualify
2316                     : Errors.NoSwitchExpression);
2317             attribTree(tree.value, env, unknownExprInfo);
2318         }
2319         result = null;
2320     }
2321 
2322     public void visitContinue(JCContinue tree) {
2323         tree.target = findJumpTarget(tree.pos(), tree.getTag(), tree.label, env);
2324         result = null;
2325     }
2326     //where
2327         /** Return the target of a break, continue or yield statement,
2328          *  if it exists, report an error if not.
2329          *  Note: The target of a labelled break or continue is the
2330          *  (non-labelled) statement tree referred to by the label,
2331          *  not the tree representing the labelled statement itself.
2332          *
2333          *  @param pos     The position to be used for error diagnostics
2334          *  @param tag     The tag of the jump statement. This is either
2335          *                 Tree.BREAK or Tree.CONTINUE.
2336          *  @param label   The label of the jump statement, or null if no
2337          *                 label is given.
2338          *  @param env     The environment current at the jump statement.
2339          */
2340         private JCTree findJumpTarget(DiagnosticPosition pos,
2341                                                    JCTree.Tag tag,
2342                                                    Name label,
2343                                                    Env<AttrContext> env) {
2344             Pair<JCTree, Error> jumpTarget = findJumpTargetNoError(tag, label, env);
2345 
2346             if (jumpTarget.snd != null) {
2347                 log.error(pos, jumpTarget.snd);
2348             }
2349 
2350             return jumpTarget.fst;
2351         }
2352         /** Return the target of a break or continue statement, if it exists,
2353          *  report an error if not.
2354          *  Note: The target of a labelled break or continue is the
2355          *  (non-labelled) statement tree referred to by the label,
2356          *  not the tree representing the labelled statement itself.
2357          *
2358          *  @param tag     The tag of the jump statement. This is either
2359          *                 Tree.BREAK or Tree.CONTINUE.
2360          *  @param label   The label of the jump statement, or null if no
2361          *                 label is given.
2362          *  @param env     The environment current at the jump statement.
2363          */
2364         private Pair<JCTree, JCDiagnostic.Error> findJumpTargetNoError(JCTree.Tag tag,
2365                                                                        Name label,
2366                                                                        Env<AttrContext> env) {
2367             // Search environments outwards from the point of jump.
2368             Env<AttrContext> env1 = env;
2369             JCDiagnostic.Error pendingError = null;
2370             LOOP:
2371             while (env1 != null) {
2372                 switch (env1.tree.getTag()) {
2373                     case LABELLED:
2374                         JCLabeledStatement labelled = (JCLabeledStatement)env1.tree;
2375                         if (label == labelled.label) {
2376                             // If jump is a continue, check that target is a loop.
2377                             if (tag == CONTINUE) {
2378                                 if (!labelled.body.hasTag(DOLOOP) &&
2379                                         !labelled.body.hasTag(WHILELOOP) &&
2380                                         !labelled.body.hasTag(FORLOOP) &&
2381                                         !labelled.body.hasTag(FOREACHLOOP)) {
2382                                     pendingError = Errors.NotLoopLabel(label);
2383                                 }
2384                                 // Found labelled statement target, now go inwards
2385                                 // to next non-labelled tree.
2386                                 return Pair.of(TreeInfo.referencedStatement(labelled), pendingError);
2387                             } else {
2388                                 return Pair.of(labelled, pendingError);
2389                             }
2390                         }
2391                         break;
2392                     case DOLOOP:
2393                     case WHILELOOP:
2394                     case FORLOOP:
2395                     case FOREACHLOOP:
2396                         if (label == null) return Pair.of(env1.tree, pendingError);
2397                         break;
2398                     case SWITCH:
2399                         if (label == null && tag == BREAK) return Pair.of(env1.tree, null);
2400                         break;
2401                     case SWITCH_EXPRESSION:
2402                         if (tag == YIELD) {
2403                             return Pair.of(env1.tree, null);
2404                         } else if (tag == BREAK) {
2405                             pendingError = Errors.BreakOutsideSwitchExpression;
2406                         } else {
2407                             pendingError = Errors.ContinueOutsideSwitchExpression;
2408                         }
2409                         break;
2410                     case LAMBDA:
2411                     case METHODDEF:
2412                     case CLASSDEF:
2413                         break LOOP;
2414                     default:
2415                 }
2416                 env1 = env1.next;
2417             }
2418             if (label != null)
2419                 return Pair.of(null, Errors.UndefLabel(label));
2420             else if (pendingError != null)
2421                 return Pair.of(null, pendingError);
2422             else if (tag == CONTINUE)
2423                 return Pair.of(null, Errors.ContOutsideLoop);
2424             else
2425                 return Pair.of(null, Errors.BreakOutsideSwitchLoop);
2426         }
2427 
2428     public void visitReturn(JCReturn tree) {
2429         // Check that there is an enclosing method which is
2430         // nested within than the enclosing class.
2431         if (env.info.returnResult == null) {
2432             log.error(tree.pos(), Errors.RetOutsideMeth);
2433         } else if (env.info.yieldResult != null) {
2434             log.error(tree.pos(), Errors.ReturnOutsideSwitchExpression);
2435         } else if (!env.info.isLambda &&
2436                 !env.info.isNewClass &&
2437                 env.enclMethod != null &&
2438                 TreeInfo.isCompactConstructor(env.enclMethod)) {
2439             log.error(env.enclMethod,
2440                     Errors.InvalidCanonicalConstructorInRecord(Fragments.Compact, env.enclMethod.sym.name, Fragments.CanonicalCantHaveReturnStatement));
2441         } else {
2442             // Attribute return expression, if it exists, and check that
2443             // it conforms to result type of enclosing method.
2444             if (tree.expr != null) {
2445                 if (env.info.returnResult.pt.hasTag(VOID)) {
2446                     env.info.returnResult.checkContext.report(tree.expr.pos(),
2447                               diags.fragment(Fragments.UnexpectedRetVal));
2448                 }
2449                 attribTree(tree.expr, env, env.info.returnResult);
2450             } else if (!env.info.returnResult.pt.hasTag(VOID) &&
2451                     !env.info.returnResult.pt.hasTag(NONE)) {
2452                 env.info.returnResult.checkContext.report(tree.pos(),
2453                               diags.fragment(Fragments.MissingRetVal(env.info.returnResult.pt)));
2454             }
2455         }
2456         result = null;
2457     }
2458 
2459     public void visitThrow(JCThrow tree) {
2460         Type owntype = attribExpr(tree.expr, env, allowPoly ? Type.noType : syms.throwableType);
2461         if (allowPoly) {
2462             chk.checkType(tree, owntype, syms.throwableType);
2463         }
2464         result = null;
2465     }
2466 
2467     public void visitAssert(JCAssert tree) {
2468         attribExpr(tree.cond, env, syms.booleanType);
2469         if (tree.detail != null) {
2470             chk.checkNonVoid(tree.detail.pos(), attribExpr(tree.detail, env));
2471         }
2472         result = null;
2473     }
2474 
2475      /** Visitor method for method invocations.
2476      *  NOTE: The method part of an application will have in its type field
2477      *        the return type of the method, not the method's type itself!
2478      */
2479     public void visitApply(JCMethodInvocation tree) {
2480         // The local environment of a method application is
2481         // a new environment nested in the current one.
2482         Env<AttrContext> localEnv = env.dup(tree, env.info.dup());
2483 
2484         // The types of the actual method arguments.
2485         List<Type> argtypes;
2486 
2487         // The types of the actual method type arguments.
2488         List<Type> typeargtypes = null;
2489 
2490         Name methName = TreeInfo.name(tree.meth);
2491 
2492         boolean isConstructorCall =
2493             methName == names._this || methName == names._super;
2494 
2495         ListBuffer<Type> argtypesBuf = new ListBuffer<>();
2496         if (isConstructorCall) {
2497             // We are seeing a ...this(...) or ...super(...) call.
2498             // Check that this is the first statement in a constructor.
2499             checkFirstConstructorStat(tree, env.enclMethod, true);
2500 
2501             // Record the fact
2502             // that this is a constructor call (using isSelfCall).
2503             localEnv.info.isSelfCall = true;
2504 
2505             // Attribute arguments, yielding list of argument types.
2506             localEnv.info.constructorArgs = true;
2507             KindSelector kind = attribArgs(KindSelector.MTH, tree.args, localEnv, argtypesBuf);
2508             localEnv.info.constructorArgs = false;
2509             argtypes = argtypesBuf.toList();
2510             typeargtypes = attribTypes(tree.typeargs, localEnv);
2511 
2512             // Variable `site' points to the class in which the called
2513             // constructor is defined.
2514             Type site = env.enclClass.sym.type;
2515             if (methName == names._super) {
2516                 if (site == syms.objectType) {
2517                     log.error(tree.meth.pos(), Errors.NoSuperclass(site));
2518                     site = types.createErrorType(syms.objectType);
2519                 } else {
2520                     site = types.supertype(site);
2521                 }
2522             }
2523 
2524             if (site.hasTag(CLASS)) {
2525                 Type encl = site.getEnclosingType();
2526                 while (encl != null && encl.hasTag(TYPEVAR))
2527                     encl = encl.getUpperBound();
2528                 if (encl.hasTag(CLASS)) {
2529                     // we are calling a nested class
2530 
2531                     if (tree.meth.hasTag(SELECT)) {
2532                         JCTree qualifier = ((JCFieldAccess) tree.meth).selected;
2533 
2534                         // We are seeing a prefixed call, of the form
2535                         //     <expr>.super(...).
2536                         // Check that the prefix expression conforms
2537                         // to the outer instance type of the class.
2538                         chk.checkRefType(qualifier.pos(),
2539                                          attribExpr(qualifier, localEnv,
2540                                                     encl));
2541                     } else if (methName == names._super) {
2542                         // qualifier omitted; check for existence
2543                         // of an appropriate implicit qualifier.
2544                         rs.resolveImplicitThis(tree.meth.pos(),
2545                                                localEnv, site, true);
2546                     }
2547                 } else if (tree.meth.hasTag(SELECT)) {
2548                     log.error(tree.meth.pos(),
2549                               Errors.IllegalQualNotIcls(site.tsym));
2550                     attribExpr(((JCFieldAccess) tree.meth).selected, localEnv, site);
2551                 }
2552 
2553                 // if we're calling a java.lang.Enum constructor,
2554                 // prefix the implicit String and int parameters
2555                 if (site.tsym == syms.enumSym)
2556                     argtypes = argtypes.prepend(syms.intType).prepend(syms.stringType);
2557 
2558                 // Resolve the called constructor under the assumption
2559                 // that we are referring to a superclass instance of the
2560                 // current instance (JLS ???).
2561                 boolean selectSuperPrev = localEnv.info.selectSuper;
2562                 localEnv.info.selectSuper = true;
2563                 localEnv.info.pendingResolutionPhase = null;
2564                 Symbol sym = rs.resolveConstructor(
2565                     tree.meth.pos(), localEnv, site, argtypes, typeargtypes);
2566                 localEnv.info.selectSuper = selectSuperPrev;
2567 
2568                 // Set method symbol to resolved constructor...
2569                 TreeInfo.setSymbol(tree.meth, sym);
2570 
2571                 // ...and check that it is legal in the current context.
2572                 // (this will also set the tree's type)
2573                 Type mpt = newMethodTemplate(resultInfo.pt, argtypes, typeargtypes);
2574                 checkId(tree.meth, site, sym, localEnv,
2575                         new ResultInfo(kind, mpt));
2576             } else if (site.hasTag(ERROR) && tree.meth.hasTag(SELECT)) {
2577                 attribExpr(((JCFieldAccess) tree.meth).selected, localEnv, site);
2578             }
2579             // Otherwise, `site' is an error type and we do nothing
2580             result = tree.type = syms.voidType;
2581         } else {
2582             // Otherwise, we are seeing a regular method call.
2583             // Attribute the arguments, yielding list of argument types, ...
2584             KindSelector kind = attribArgs(KindSelector.VAL, tree.args, localEnv, argtypesBuf);
2585             argtypes = argtypesBuf.toList();
2586             typeargtypes = attribAnyTypes(tree.typeargs, localEnv);
2587 
2588             // ... and attribute the method using as a prototype a methodtype
2589             // whose formal argument types is exactly the list of actual
2590             // arguments (this will also set the method symbol).
2591             Type mpt = newMethodTemplate(resultInfo.pt, argtypes, typeargtypes);
2592             localEnv.info.pendingResolutionPhase = null;
2593             Type mtype = attribTree(tree.meth, localEnv, new ResultInfo(kind, mpt, resultInfo.checkContext));
2594 
2595             // Compute the result type.
2596             Type restype = mtype.getReturnType();
2597             if (restype.hasTag(WILDCARD))
2598                 throw new AssertionError(mtype);
2599 
2600             Type qualifier = (tree.meth.hasTag(SELECT))
2601                     ? ((JCFieldAccess) tree.meth).selected.type
2602                     : env.enclClass.sym.type;
2603             Symbol msym = TreeInfo.symbol(tree.meth);
2604             restype = adjustMethodReturnType(msym, qualifier, methName, argtypes, restype);
2605 
2606             chk.checkRefTypes(tree.typeargs, typeargtypes);
2607 
2608             final Symbol symbol = TreeInfo.symbol(tree.meth);
2609             if (symbol != null) {
2610                 /* Is this an ill-conceived attempt to invoke jlO methods not available on value class types ??
2611                  */
2612                 boolean superCallOnValueReceiver = env.enclClass.sym.type.isValueClass()
2613                         && (tree.meth.hasTag(SELECT))
2614                         && ((JCFieldAccess)tree.meth).selected.hasTag(IDENT)
2615                         && TreeInfo.name(((JCFieldAccess)tree.meth).selected) == names._super;
2616                 if (qualifier.isValueClass() || superCallOnValueReceiver) {
2617                     int argSize = argtypes.size();
2618                     Name name = symbol.name;
2619                     switch (name.toString()) {
2620                         case "wait":
2621                             if (argSize == 0
2622                                     || (types.isConvertible(argtypes.head, syms.longType) &&
2623                                     (argSize == 1 || (argSize == 2 && types.isConvertible(argtypes.tail.head, syms.intType))))) {
2624                                 log.error(tree.pos(), Errors.ValueClassDoesNotSupport(name));
2625                             }
2626                             break;
2627                         case "notify":
2628                         case "notifyAll":
2629                         case "finalize":
2630                             if (argSize == 0)
2631                                 log.error(tree.pos(), Errors.ValueClassDoesNotSupport(name));
2632                             break;
2633                     }
2634                 }
2635             }
2636 
2637             // Check that value of resulting type is admissible in the
2638             // current context.  Also, capture the return type
2639             Type capturedRes = resultInfo.checkContext.inferenceContext().cachedCapture(tree, restype, true);
2640             result = check(tree, capturedRes, KindSelector.VAL, resultInfo);
2641         }
2642         chk.validate(tree.typeargs, localEnv);
2643     }
2644     //where
2645         Type adjustMethodReturnType(Symbol msym, Type qualifierType, Name methodName, List<Type> argtypes, Type restype) {
2646             if (msym != null &&
2647                     (msym.owner == syms.objectType.tsym || msym.owner.isInterface()) &&
2648                     methodName == names.getClass &&
2649                     argtypes.isEmpty()) {
2650                 // as a special case, x.getClass() has type Class<? extends |X|>
2651                 // Special treatment for primitive classes: Given an expression v of type V where
2652                 // V is a primitive class, v.getClass() is typed to be Class<? extends |V.ref|>
2653                 Type wcb = types.erasure(qualifierType.isPrimitiveClass() ?
2654                                                 qualifierType.referenceProjection() : qualifierType);
2655                 return new ClassType(restype.getEnclosingType(),
2656                         List.of(new WildcardType(wcb,
2657                                 BoundKind.EXTENDS,
2658                                 syms.boundClass)),
2659                         restype.tsym,
2660                         restype.getMetadata(),
2661                         restype.getFlavor());
2662             } else if (msym != null &&
2663                     msym.owner == syms.arrayClass &&
2664                     methodName == names.clone &&
2665                     types.isArray(qualifierType)) {
2666                 // as a special case, array.clone() has a result that is
2667                 // the same as static type of the array being cloned
2668                 return qualifierType;
2669             } else {
2670                 return restype;
2671             }
2672         }
2673 
2674         /** Check that given application node appears as first statement
2675          *  in a constructor call.
2676          *  @param tree          The application node
2677          *  @param enclMethod    The enclosing method of the application.
2678          *  @param error         Should an error be issued?
2679          */
2680         boolean checkFirstConstructorStat(JCMethodInvocation tree, JCMethodDecl enclMethod, boolean error) {
2681             if (enclMethod != null && enclMethod.name == names.init) {
2682                 JCBlock body = enclMethod.body;
2683                 if (body.stats.head.hasTag(EXEC) &&
2684                     ((JCExpressionStatement) body.stats.head).expr == tree)
2685                     return true;
2686             }
2687             if (error) {
2688                 log.error(tree.pos(),
2689                         Errors.CallMustBeFirstStmtInCtor(TreeInfo.name(tree.meth)));
2690             }
2691             return false;
2692         }
2693 
2694         /** Obtain a method type with given argument types.
2695          */
2696         Type newMethodTemplate(Type restype, List<Type> argtypes, List<Type> typeargtypes) {
2697             MethodType mt = new MethodType(argtypes, restype, List.nil(), syms.methodClass);
2698             return (typeargtypes == null) ? mt : (Type)new ForAll(typeargtypes, mt);
2699         }
2700 
2701     public void visitNewClass(final JCNewClass tree) {
2702         Type owntype = types.createErrorType(tree.type);
2703 
2704         // The local environment of a class creation is
2705         // a new environment nested in the current one.
2706         Env<AttrContext> localEnv = env.dup(tree, env.info.dup());
2707 
2708         // The anonymous inner class definition of the new expression,
2709         // if one is defined by it.
2710         JCClassDecl cdef = tree.def;
2711 
2712         // If enclosing class is given, attribute it, and
2713         // complete class name to be fully qualified
2714         JCExpression clazz = tree.clazz; // Class field following new
2715         JCExpression clazzid;            // Identifier in class field
2716         JCAnnotatedType annoclazzid;     // Annotated type enclosing clazzid
2717         annoclazzid = null;
2718 
2719         if (clazz.hasTag(TYPEAPPLY)) {
2720             clazzid = ((JCTypeApply) clazz).clazz;
2721             if (clazzid.hasTag(ANNOTATED_TYPE)) {
2722                 annoclazzid = (JCAnnotatedType) clazzid;
2723                 clazzid = annoclazzid.underlyingType;
2724             }
2725         } else {
2726             if (clazz.hasTag(ANNOTATED_TYPE)) {
2727                 annoclazzid = (JCAnnotatedType) clazz;
2728                 clazzid = annoclazzid.underlyingType;
2729             } else {
2730                 clazzid = clazz;
2731             }
2732         }
2733 
2734         JCExpression clazzid1 = clazzid; // The same in fully qualified form
2735 
2736         if (tree.encl != null) {
2737             // We are seeing a qualified new, of the form
2738             //    <expr>.new C <...> (...) ...
2739             // In this case, we let clazz stand for the name of the
2740             // allocated class C prefixed with the type of the qualifier
2741             // expression, so that we can
2742             // resolve it with standard techniques later. I.e., if
2743             // <expr> has type T, then <expr>.new C <...> (...)
2744             // yields a clazz T.C.
2745             Type encltype = chk.checkRefType(tree.encl.pos(),
2746                                              attribExpr(tree.encl, env));
2747             // TODO 308: in <expr>.new C, do we also want to add the type annotations
2748             // from expr to the combined type, or not? Yes, do this.
2749             clazzid1 = make.at(clazz.pos).Select(make.Type(encltype),
2750                                                  ((JCIdent) clazzid).name);
2751 
2752             EndPosTable endPosTable = this.env.toplevel.endPositions;
2753             endPosTable.storeEnd(clazzid1, clazzid.getEndPosition(endPosTable));
2754             if (clazz.hasTag(ANNOTATED_TYPE)) {
2755                 JCAnnotatedType annoType = (JCAnnotatedType) clazz;
2756                 List<JCAnnotation> annos = annoType.annotations;
2757 
2758                 if (annoType.underlyingType.hasTag(TYPEAPPLY)) {
2759                     clazzid1 = make.at(tree.pos).
2760                         TypeApply(clazzid1,
2761                                   ((JCTypeApply) clazz).arguments);
2762                 }
2763 
2764                 clazzid1 = make.at(tree.pos).
2765                     AnnotatedType(annos, clazzid1);
2766             } else if (clazz.hasTag(TYPEAPPLY)) {
2767                 clazzid1 = make.at(tree.pos).
2768                     TypeApply(clazzid1,
2769                               ((JCTypeApply) clazz).arguments);
2770             }
2771 
2772             clazz = clazzid1;
2773         }
2774 
2775         // Attribute clazz expression and store
2776         // symbol + type back into the attributed tree.
2777         Type clazztype;
2778 
2779         try {
2780             env.info.isNewClass = true;
2781             clazztype = TreeInfo.isEnumInit(env.tree) ?
2782                 attribIdentAsEnumType(env, (JCIdent)clazz) :
2783                 attribType(clazz, env);
2784         } finally {
2785             env.info.isNewClass = false;
2786         }
2787 
2788         clazztype = chk.checkDiamond(tree, clazztype);
2789         chk.validate(clazz, localEnv);
2790         if (tree.encl != null) {
2791             // We have to work in this case to store
2792             // symbol + type back into the attributed tree.
2793             tree.clazz.type = clazztype;
2794             TreeInfo.setSymbol(clazzid, TreeInfo.symbol(clazzid1));
2795             clazzid.type = ((JCIdent) clazzid).sym.type;
2796             if (annoclazzid != null) {
2797                 annoclazzid.type = clazzid.type;
2798             }
2799             if (!clazztype.isErroneous()) {
2800                 if (cdef != null && clazztype.tsym.isInterface()) {
2801                     log.error(tree.encl.pos(), Errors.AnonClassImplIntfNoQualForNew);
2802                 } else if (clazztype.tsym.isStatic()) {
2803                     log.error(tree.encl.pos(), Errors.QualifiedNewOfStaticClass(clazztype.tsym));
2804                 }
2805             }
2806         } else if (!clazztype.tsym.isInterface() &&
2807                    clazztype.getEnclosingType().hasTag(CLASS)) {
2808             // Check for the existence of an apropos outer instance
2809             rs.resolveImplicitThis(tree.pos(), env, clazztype);
2810         }
2811 
2812         // Attribute constructor arguments.
2813         ListBuffer<Type> argtypesBuf = new ListBuffer<>();
2814         final KindSelector pkind =
2815             attribArgs(KindSelector.VAL, tree.args, localEnv, argtypesBuf);
2816         List<Type> argtypes = argtypesBuf.toList();
2817         List<Type> typeargtypes = attribTypes(tree.typeargs, localEnv);
2818 
2819         if (clazztype.hasTag(CLASS) || clazztype.hasTag(ERROR)) {
2820             // Enums may not be instantiated except implicitly
2821             if ((clazztype.tsym.flags_field & Flags.ENUM) != 0 &&
2822                 (!env.tree.hasTag(VARDEF) ||
2823                  (((JCVariableDecl) env.tree).mods.flags & Flags.ENUM) == 0 ||
2824                  ((JCVariableDecl) env.tree).init != tree))
2825                 log.error(tree.pos(), Errors.EnumCantBeInstantiated);
2826 
2827             boolean isSpeculativeDiamondInferenceRound = TreeInfo.isDiamond(tree) &&
2828                     resultInfo.checkContext.deferredAttrContext().mode == DeferredAttr.AttrMode.SPECULATIVE;
2829             boolean skipNonDiamondPath = false;
2830             // Check that it is an instantiation of a class and not a projection type
2831             if (clazz.hasTag(SELECT)) {
2832                 JCFieldAccess fieldAccess = (JCFieldAccess) clazz;
2833                 if (fieldAccess.selected.type.isPrimitiveClass() &&
2834                         (fieldAccess.name == names.ref || fieldAccess.name == names.val)) {
2835                     log.error(tree.pos(), Errors.ProjectionCantBeInstantiated);
2836                 }
2837             }
2838             // Check that class is not abstract
2839             if (cdef == null && !isSpeculativeDiamondInferenceRound && // class body may be nulled out in speculative tree copy
2840                 (clazztype.tsym.flags() & (ABSTRACT | INTERFACE)) != 0) {
2841                 log.error(tree.pos(),
2842                           Errors.AbstractCantBeInstantiated(clazztype.tsym));
2843                 skipNonDiamondPath = true;
2844             } else if (cdef != null && clazztype.tsym.isInterface()) {
2845                 // Check that no constructor arguments are given to
2846                 // anonymous classes implementing an interface
2847                 if (!argtypes.isEmpty())
2848                     log.error(tree.args.head.pos(), Errors.AnonClassImplIntfNoArgs);
2849 
2850                 if (!typeargtypes.isEmpty())
2851                     log.error(tree.typeargs.head.pos(), Errors.AnonClassImplIntfNoTypeargs);
2852 
2853                 // Error recovery: pretend no arguments were supplied.
2854                 argtypes = List.nil();
2855                 typeargtypes = List.nil();
2856                 skipNonDiamondPath = true;
2857             }
2858             if (TreeInfo.isDiamond(tree)) {
2859                 ClassType site = new ClassType(clazztype.getEnclosingType(),
2860                             clazztype.tsym.type.getTypeArguments(),
2861                                                clazztype.tsym,
2862                                                clazztype.getMetadata(),
2863                                                clazztype.getFlavor());
2864 
2865                 Env<AttrContext> diamondEnv = localEnv.dup(tree);
2866                 diamondEnv.info.selectSuper = cdef != null || tree.classDeclRemoved();
2867                 diamondEnv.info.pendingResolutionPhase = null;
2868 
2869                 //if the type of the instance creation expression is a class type
2870                 //apply method resolution inference (JLS 15.12.2.7). The return type
2871                 //of the resolved constructor will be a partially instantiated type
2872                 Symbol constructor = rs.resolveDiamond(tree.pos(),
2873                             diamondEnv,
2874                             site,
2875                             argtypes,
2876                             typeargtypes);
2877                 tree.constructor = constructor.baseSymbol();
2878 
2879                 final TypeSymbol csym = clazztype.tsym;
2880                 ResultInfo diamondResult = new ResultInfo(pkind, newMethodTemplate(resultInfo.pt, argtypes, typeargtypes),
2881                         diamondContext(tree, csym, resultInfo.checkContext), CheckMode.NO_TREE_UPDATE);
2882                 Type constructorType = tree.constructorType = types.createErrorType(clazztype);
2883                 constructorType = checkId(tree, site,
2884                         constructor,
2885                         diamondEnv,
2886                         diamondResult);
2887 
2888                 tree.clazz.type = types.createErrorType(clazztype);
2889                 if (!constructorType.isErroneous()) {
2890                     tree.clazz.type = clazz.type = constructorType.getReturnType();
2891                     tree.constructorType = types.createMethodTypeWithReturn(constructorType, syms.voidType);
2892                 }
2893                 clazztype = chk.checkClassType(tree.clazz, tree.clazz.type, true);
2894             }
2895 
2896             // Resolve the called constructor under the assumption
2897             // that we are referring to a superclass instance of the
2898             // current instance (JLS ???).
2899             else if (!skipNonDiamondPath) {
2900                 //the following code alters some of the fields in the current
2901                 //AttrContext - hence, the current context must be dup'ed in
2902                 //order to avoid downstream failures
2903                 Env<AttrContext> rsEnv = localEnv.dup(tree);
2904                 rsEnv.info.selectSuper = cdef != null;
2905                 rsEnv.info.pendingResolutionPhase = null;
2906                 tree.constructor = rs.resolveConstructor(
2907                     tree.pos(), rsEnv, clazztype, argtypes, typeargtypes);
2908                 if (cdef == null) { //do not check twice!
2909                     tree.constructorType = checkId(tree,
2910                             clazztype,
2911                             tree.constructor,
2912                             rsEnv,
2913                             new ResultInfo(pkind, newMethodTemplate(syms.voidType, argtypes, typeargtypes), CheckMode.NO_TREE_UPDATE));
2914                     if (rsEnv.info.lastResolveVarargs())
2915                         Assert.check(tree.constructorType.isErroneous() || tree.varargsElement != null);
2916                 }
2917             }
2918 
2919             if (cdef != null) {
2920                 visitAnonymousClassDefinition(tree, clazz, clazztype, cdef, localEnv, argtypes, typeargtypes, pkind);
2921                 return;
2922             }
2923 
2924             if (tree.constructor != null && tree.constructor.kind == MTH)
2925                 owntype = clazztype;
2926         }
2927         result = check(tree, owntype, KindSelector.VAL, resultInfo);
2928         InferenceContext inferenceContext = resultInfo.checkContext.inferenceContext();
2929         if (tree.constructorType != null && inferenceContext.free(tree.constructorType)) {
2930             //we need to wait for inference to finish and then replace inference vars in the constructor type
2931             inferenceContext.addFreeTypeListener(List.of(tree.constructorType),
2932                     instantiatedContext -> {
2933                         tree.constructorType = instantiatedContext.asInstType(tree.constructorType);
2934                     });
2935         }
2936         chk.validate(tree.typeargs, localEnv);
2937     }
2938 
2939         // where
2940         private void visitAnonymousClassDefinition(JCNewClass tree, JCExpression clazz, Type clazztype,
2941                                                    JCClassDecl cdef, Env<AttrContext> localEnv,
2942                                                    List<Type> argtypes, List<Type> typeargtypes,
2943                                                    KindSelector pkind) {
2944             // We are seeing an anonymous class instance creation.
2945             // In this case, the class instance creation
2946             // expression
2947             //
2948             //    E.new <typeargs1>C<typargs2>(args) { ... }
2949             //
2950             // is represented internally as
2951             //
2952             //    E . new <typeargs1>C<typargs2>(args) ( class <empty-name> { ... } )  .
2953             //
2954             // This expression is then *transformed* as follows:
2955             //
2956             // (1) add an extends or implements clause
2957             // (2) add a constructor.
2958             //
2959             // For instance, if C is a class, and ET is the type of E,
2960             // the expression
2961             //
2962             //    E.new <typeargs1>C<typargs2>(args) { ... }
2963             //
2964             // is translated to (where X is a fresh name and typarams is the
2965             // parameter list of the super constructor):
2966             //
2967             //   new <typeargs1>X(<*nullchk*>E, args) where
2968             //     X extends C<typargs2> {
2969             //       <typarams> X(ET e, args) {
2970             //         e.<typeargs1>super(args)
2971             //       }
2972             //       ...
2973             //     }
2974             InferenceContext inferenceContext = resultInfo.checkContext.inferenceContext();
2975             Type enclType = clazztype.getEnclosingType();
2976             if (enclType != null &&
2977                     enclType.hasTag(CLASS) &&
2978                     !chk.checkDenotable((ClassType)enclType)) {
2979                 log.error(tree.encl, Errors.EnclosingClassTypeNonDenotable(enclType));
2980             }
2981             final boolean isDiamond = TreeInfo.isDiamond(tree);
2982             if (isDiamond
2983                     && ((tree.constructorType != null && inferenceContext.free(tree.constructorType))
2984                     || (tree.clazz.type != null && inferenceContext.free(tree.clazz.type)))) {
2985                 final ResultInfo resultInfoForClassDefinition = this.resultInfo;
2986                 Env<AttrContext> dupLocalEnv = localEnv.dup(localEnv.tree, localEnv.info.dup(localEnv.info.scope.dupUnshared()));
2987                 inferenceContext.addFreeTypeListener(List.of(tree.constructorType, tree.clazz.type),
2988                         instantiatedContext -> {
2989                             tree.constructorType = instantiatedContext.asInstType(tree.constructorType);
2990                             tree.clazz.type = clazz.type = instantiatedContext.asInstType(clazz.type);
2991                             ResultInfo prevResult = this.resultInfo;
2992                             try {
2993                                 this.resultInfo = resultInfoForClassDefinition;
2994                                 visitAnonymousClassDefinition(tree, clazz, clazz.type, cdef,
2995                                         dupLocalEnv, argtypes, typeargtypes, pkind);
2996                             } finally {
2997                                 this.resultInfo = prevResult;
2998                             }
2999                         });
3000             } else {
3001                 if (isDiamond && clazztype.hasTag(CLASS)) {
3002                     List<Type> invalidDiamondArgs = chk.checkDiamondDenotable((ClassType)clazztype);
3003                     if (!clazztype.isErroneous() && invalidDiamondArgs.nonEmpty()) {
3004                         // One or more types inferred in the previous steps is non-denotable.
3005                         Fragment fragment = Diamond(clazztype.tsym);
3006                         log.error(tree.clazz.pos(),
3007                                 Errors.CantApplyDiamond1(
3008                                         fragment,
3009                                         invalidDiamondArgs.size() > 1 ?
3010                                                 DiamondInvalidArgs(invalidDiamondArgs, fragment) :
3011                                                 DiamondInvalidArg(invalidDiamondArgs, fragment)));
3012                     }
3013                     // For <>(){}, inferred types must also be accessible.
3014                     for (Type t : clazztype.getTypeArguments()) {
3015                         rs.checkAccessibleType(env, t);
3016                     }
3017                     chk.checkParameterizationByPrimitiveClass(tree, clazztype);
3018                 }
3019 
3020                 // If we already errored, be careful to avoid a further avalanche. ErrorType answers
3021                 // false for isInterface call even when the original type is an interface.
3022                 boolean implementing = clazztype.tsym.isInterface() ||
3023                         clazztype.isErroneous() && !clazztype.getOriginalType().hasTag(NONE) &&
3024                         clazztype.getOriginalType().tsym.isInterface();
3025 
3026                 if (implementing) {
3027                     cdef.implementing = List.of(clazz);
3028                 } else {
3029                     cdef.extending = clazz;
3030                 }
3031 
3032                 if (resultInfo.checkContext.deferredAttrContext().mode == DeferredAttr.AttrMode.CHECK &&
3033                     rs.isSerializable(clazztype)) {
3034                     localEnv.info.isSerializable = true;
3035                 }
3036 
3037                 attribStat(cdef, localEnv);
3038 
3039                 List<Type> finalargtypes;
3040                 // If an outer instance is given,
3041                 // prefix it to the constructor arguments
3042                 // and delete it from the new expression
3043                 if (tree.encl != null && !clazztype.tsym.isInterface()) {
3044                     finalargtypes = argtypes.prepend(tree.encl.type);
3045                 } else {
3046                     finalargtypes = argtypes;
3047                 }
3048 
3049                 // Reassign clazztype and recompute constructor. As this necessarily involves
3050                 // another attribution pass for deferred types in the case of <>, replicate
3051                 // them. Original arguments have right decorations already.
3052                 if (isDiamond && pkind.contains(KindSelector.POLY)) {
3053                     finalargtypes = finalargtypes.map(deferredAttr.deferredCopier);
3054                 }
3055 
3056                 clazztype = clazztype.hasTag(ERROR) ? types.createErrorType(cdef.sym.type)
3057                                                     : cdef.sym.type;
3058                 Symbol sym = tree.constructor = rs.resolveConstructor(
3059                         tree.pos(), localEnv, clazztype, finalargtypes, typeargtypes);
3060                 Assert.check(!sym.kind.isResolutionError());
3061                 tree.constructor = sym;
3062                 tree.constructorType = checkId(tree,
3063                         clazztype,
3064                         tree.constructor,
3065                         localEnv,
3066                         new ResultInfo(pkind, newMethodTemplate(syms.voidType, finalargtypes, typeargtypes), CheckMode.NO_TREE_UPDATE));
3067             }
3068             Type owntype = (tree.constructor != null && tree.constructor.kind == MTH) ?
3069                                 clazztype : types.createErrorType(tree.type);
3070             result = check(tree, owntype, KindSelector.VAL, resultInfo.dup(CheckMode.NO_INFERENCE_HOOK));
3071             chk.validate(tree.typeargs, localEnv);
3072         }
3073 
3074         CheckContext diamondContext(JCNewClass clazz, TypeSymbol tsym, CheckContext checkContext) {
3075             return new Check.NestedCheckContext(checkContext) {
3076                 @Override
3077                 public void report(DiagnosticPosition _unused, JCDiagnostic details) {
3078                     enclosingContext.report(clazz.clazz,
3079                             diags.fragment(Fragments.CantApplyDiamond1(Fragments.Diamond(tsym), details)));
3080                 }
3081             };
3082         }
3083 
3084     /** Make an attributed null check tree.
3085      */
3086     public JCExpression makeNullCheck(JCExpression arg) {
3087         // optimization: new Outer() can never be null; skip null check
3088         if (arg.getTag() == NEWCLASS)
3089             return arg;
3090         // Likewise arg can't be null if it is a primitive class instance.
3091         if (arg.type.isPrimitiveClass())
3092             return arg;
3093         // optimization: X.this is never null; skip null check
3094         Name name = TreeInfo.name(arg);
3095         if (name == names._this || name == names._super) return arg;
3096 
3097         JCTree.Tag optag = NULLCHK;
3098         JCUnary tree = make.at(arg.pos).Unary(optag, arg);
3099         tree.operator = operators.resolveUnary(arg, optag, arg.type);
3100         tree.type = arg.type;
3101         return tree;
3102     }
3103 
3104     public void visitNewArray(JCNewArray tree) {
3105         Type owntype = types.createErrorType(tree.type);
3106         Env<AttrContext> localEnv = env.dup(tree);
3107         Type elemtype;
3108         if (tree.elemtype != null) {
3109             elemtype = attribType(tree.elemtype, localEnv);
3110             chk.validate(tree.elemtype, localEnv);
3111             owntype = elemtype;
3112             for (List<JCExpression> l = tree.dims; l.nonEmpty(); l = l.tail) {
3113                 attribExpr(l.head, localEnv, syms.intType);
3114                 owntype = new ArrayType(owntype, syms.arrayClass);
3115             }
3116         } else {
3117             // we are seeing an untyped aggregate { ... }
3118             // this is allowed only if the prototype is an array
3119             if (pt().hasTag(ARRAY)) {
3120                 elemtype = types.elemtype(pt());
3121             } else {
3122                 if (!pt().hasTag(ERROR) &&
3123                         (env.info.enclVar == null || !env.info.enclVar.type.isErroneous())) {
3124                     log.error(tree.pos(),
3125                               Errors.IllegalInitializerForType(pt()));
3126                 }
3127                 elemtype = types.createErrorType(pt());
3128             }
3129         }
3130         if (tree.elems != null) {
3131             attribExprs(tree.elems, localEnv, elemtype);
3132             owntype = new ArrayType(elemtype, syms.arrayClass);
3133         }
3134         if (!types.isReifiable(elemtype))
3135             log.error(tree.pos(), Errors.GenericArrayCreation);
3136         result = check(tree, owntype, KindSelector.VAL, resultInfo);
3137     }
3138 
3139     /*
3140      * A lambda expression can only be attributed when a target-type is available.
3141      * In addition, if the target-type is that of a functional interface whose
3142      * descriptor contains inference variables in argument position the lambda expression
3143      * is 'stuck' (see DeferredAttr).
3144      */
3145     @Override
3146     public void visitLambda(final JCLambda that) {
3147         boolean wrongContext = false;
3148         if (pt().isErroneous() || (pt().hasTag(NONE) && pt() != Type.recoveryType)) {
3149             if (pt().hasTag(NONE) && (env.info.enclVar == null || !env.info.enclVar.type.isErroneous())) {
3150                 //lambda only allowed in assignment or method invocation/cast context
3151                 log.error(that.pos(), Errors.UnexpectedLambda);
3152             }
3153             resultInfo = recoveryInfo;
3154             wrongContext = true;
3155         }
3156         //create an environment for attribution of the lambda expression
3157         final Env<AttrContext> localEnv = lambdaEnv(that, env);
3158         boolean needsRecovery =
3159                 resultInfo.checkContext.deferredAttrContext().mode == DeferredAttr.AttrMode.CHECK;
3160         try {
3161             if (needsRecovery && rs.isSerializable(pt())) {
3162                 localEnv.info.isSerializable = true;
3163                 localEnv.info.isSerializableLambda = true;
3164             }
3165             List<Type> explicitParamTypes = null;
3166             if (that.paramKind == JCLambda.ParameterKind.EXPLICIT) {
3167                 //attribute lambda parameters
3168                 attribStats(that.params, localEnv);
3169                 explicitParamTypes = TreeInfo.types(that.params);
3170             }
3171 
3172             TargetInfo targetInfo = getTargetInfo(that, resultInfo, explicitParamTypes);
3173             Type currentTarget = targetInfo.target;
3174             Type lambdaType = targetInfo.descriptor;
3175 
3176             if (currentTarget.isErroneous()) {
3177                 result = that.type = currentTarget;
3178                 return;
3179             }
3180 
3181             setFunctionalInfo(localEnv, that, pt(), lambdaType, currentTarget, resultInfo.checkContext);
3182 
3183             if (lambdaType.hasTag(FORALL)) {
3184                 //lambda expression target desc cannot be a generic method
3185                 Fragment msg = Fragments.InvalidGenericLambdaTarget(lambdaType,
3186                                                                     kindName(currentTarget.tsym),
3187                                                                     currentTarget.tsym);
3188                 resultInfo.checkContext.report(that, diags.fragment(msg));
3189                 result = that.type = types.createErrorType(pt());
3190                 return;
3191             }
3192 
3193             if (that.paramKind == JCLambda.ParameterKind.IMPLICIT) {
3194                 //add param type info in the AST
3195                 List<Type> actuals = lambdaType.getParameterTypes();
3196                 List<JCVariableDecl> params = that.params;
3197 
3198                 boolean arityMismatch = false;
3199 
3200                 while (params.nonEmpty()) {
3201                     if (actuals.isEmpty()) {
3202                         //not enough actuals to perform lambda parameter inference
3203                         arityMismatch = true;
3204                     }
3205                     //reset previously set info
3206                     Type argType = arityMismatch ?
3207                             syms.errType :
3208                             actuals.head;
3209                     if (params.head.isImplicitlyTyped()) {
3210                         setSyntheticVariableType(params.head, argType);
3211                     }
3212                     params.head.sym = null;
3213                     actuals = actuals.isEmpty() ?
3214                             actuals :
3215                             actuals.tail;
3216                     params = params.tail;
3217                 }
3218 
3219                 //attribute lambda parameters
3220                 attribStats(that.params, localEnv);
3221 
3222                 if (arityMismatch) {
3223                     resultInfo.checkContext.report(that, diags.fragment(Fragments.IncompatibleArgTypesInLambda));
3224                         result = that.type = types.createErrorType(currentTarget);
3225                         return;
3226                 }
3227             }
3228 
3229             //from this point on, no recovery is needed; if we are in assignment context
3230             //we will be able to attribute the whole lambda body, regardless of errors;
3231             //if we are in a 'check' method context, and the lambda is not compatible
3232             //with the target-type, it will be recovered anyway in Attr.checkId
3233             needsRecovery = false;
3234 
3235             ResultInfo bodyResultInfo = localEnv.info.returnResult =
3236                     lambdaBodyResult(that, lambdaType, resultInfo);
3237 
3238             if (that.getBodyKind() == JCLambda.BodyKind.EXPRESSION) {
3239                 attribTree(that.getBody(), localEnv, bodyResultInfo);
3240             } else {
3241                 JCBlock body = (JCBlock)that.body;
3242                 if (body == breakTree &&
3243                         resultInfo.checkContext.deferredAttrContext().mode == AttrMode.CHECK) {
3244                     breakTreeFound(copyEnv(localEnv));
3245                 }
3246                 attribStats(body.stats, localEnv);
3247             }
3248 
3249             result = check(that, currentTarget, KindSelector.VAL, resultInfo);
3250 
3251             boolean isSpeculativeRound =
3252                     resultInfo.checkContext.deferredAttrContext().mode == DeferredAttr.AttrMode.SPECULATIVE;
3253 
3254             preFlow(that);
3255             flow.analyzeLambda(env, that, make, isSpeculativeRound);
3256 
3257             that.type = currentTarget; //avoids recovery at this stage
3258             checkLambdaCompatible(that, lambdaType, resultInfo.checkContext);
3259 
3260             if (!isSpeculativeRound) {
3261                 //add thrown types as bounds to the thrown types free variables if needed:
3262                 if (resultInfo.checkContext.inferenceContext().free(lambdaType.getThrownTypes())) {
3263                     List<Type> inferredThrownTypes = flow.analyzeLambdaThrownTypes(env, that, make);
3264                     if(!checkExConstraints(inferredThrownTypes, lambdaType.getThrownTypes(), resultInfo.checkContext.inferenceContext())) {
3265                         log.error(that, Errors.IncompatibleThrownTypesInMref(lambdaType.getThrownTypes()));
3266                     }
3267                 }
3268 
3269                 checkAccessibleTypes(that, localEnv, resultInfo.checkContext.inferenceContext(), lambdaType, currentTarget);
3270             }
3271             result = wrongContext ? that.type = types.createErrorType(pt())
3272                                   : check(that, currentTarget, KindSelector.VAL, resultInfo);
3273         } catch (Types.FunctionDescriptorLookupError ex) {
3274             JCDiagnostic cause = ex.getDiagnostic();
3275             resultInfo.checkContext.report(that, cause);
3276             result = that.type = types.createErrorType(pt());
3277             return;
3278         } catch (CompletionFailure cf) {
3279             chk.completionError(that.pos(), cf);
3280         } catch (Throwable t) {
3281             //when an unexpected exception happens, avoid attempts to attribute the same tree again
3282             //as that would likely cause the same exception again.
3283             needsRecovery = false;
3284             throw t;
3285         } finally {
3286             localEnv.info.scope.leave();
3287             if (needsRecovery) {
3288                 Type prevResult = result;
3289                 try {
3290                     attribTree(that, env, recoveryInfo);
3291                 } finally {
3292                     if (result == Type.recoveryType) {
3293                         result = prevResult;
3294                     }
3295                 }
3296             }
3297         }
3298     }
3299     //where
3300         class TargetInfo {
3301             Type target;
3302             Type descriptor;
3303 
3304             public TargetInfo(Type target, Type descriptor) {
3305                 this.target = target;
3306                 this.descriptor = descriptor;
3307             }
3308         }
3309 
3310         TargetInfo getTargetInfo(JCPolyExpression that, ResultInfo resultInfo, List<Type> explicitParamTypes) {
3311             Type lambdaType;
3312             Type currentTarget = resultInfo.pt;
3313             if (resultInfo.pt != Type.recoveryType) {
3314                 /* We need to adjust the target. If the target is an
3315                  * intersection type, for example: SAM & I1 & I2 ...
3316                  * the target will be updated to SAM
3317                  */
3318                 currentTarget = targetChecker.visit(currentTarget, that);
3319                 if (!currentTarget.isIntersection()) {
3320                     if (explicitParamTypes != null) {
3321                         currentTarget = infer.instantiateFunctionalInterface(that,
3322                                 currentTarget, explicitParamTypes, resultInfo.checkContext);
3323                     }
3324                     currentTarget = types.removeWildcards(currentTarget);
3325                     lambdaType = types.findDescriptorType(currentTarget);
3326                 } else {
3327                     IntersectionClassType ict = (IntersectionClassType)currentTarget;
3328                     ListBuffer<Type> components = new ListBuffer<>();
3329                     for (Type bound : ict.getExplicitComponents()) {
3330                         if (explicitParamTypes != null) {
3331                             try {
3332                                 bound = infer.instantiateFunctionalInterface(that,
3333                                         bound, explicitParamTypes, resultInfo.checkContext);
3334                             } catch (FunctionDescriptorLookupError t) {
3335                                 // do nothing
3336                             }
3337                         }
3338                         bound = types.removeWildcards(bound);
3339                         components.add(bound);
3340                     }
3341                     currentTarget = types.makeIntersectionType(components.toList());
3342                     currentTarget.tsym.flags_field |= INTERFACE;
3343                     lambdaType = types.findDescriptorType(currentTarget);
3344                 }
3345 
3346             } else {
3347                 currentTarget = Type.recoveryType;
3348                 lambdaType = fallbackDescriptorType(that);
3349             }
3350             if (that.hasTag(LAMBDA) && lambdaType.hasTag(FORALL)) {
3351                 //lambda expression target desc cannot be a generic method
3352                 Fragment msg = Fragments.InvalidGenericLambdaTarget(lambdaType,
3353                                                                     kindName(currentTarget.tsym),
3354                                                                     currentTarget.tsym);
3355                 resultInfo.checkContext.report(that, diags.fragment(msg));
3356                 currentTarget = types.createErrorType(pt());
3357             }
3358             return new TargetInfo(currentTarget, lambdaType);
3359         }
3360 
3361         void preFlow(JCLambda tree) {
3362             attrRecover.doRecovery();
3363             new PostAttrAnalyzer() {
3364                 @Override
3365                 public void scan(JCTree tree) {
3366                     if (tree == null ||
3367                             (tree.type != null &&
3368                             tree.type == Type.stuckType)) {
3369                         //don't touch stuck expressions!
3370                         return;
3371                     }
3372                     super.scan(tree);
3373                 }
3374 
3375                 @Override
3376                 public void visitClassDef(JCClassDecl that) {
3377                     // or class declaration trees!
3378                 }
3379 
3380                 public void visitLambda(JCLambda that) {
3381                     // or lambda expressions!
3382                 }
3383             }.scan(tree.body);
3384         }
3385 
3386         Types.MapVisitor<DiagnosticPosition> targetChecker = new Types.MapVisitor<DiagnosticPosition>() {
3387 
3388             @Override
3389             public Type visitClassType(ClassType t, DiagnosticPosition pos) {
3390                 return t.isIntersection() ?
3391                         visitIntersectionClassType((IntersectionClassType)t, pos) : t;
3392             }
3393 
3394             public Type visitIntersectionClassType(IntersectionClassType ict, DiagnosticPosition pos) {
3395                 types.findDescriptorSymbol(makeNotionalInterface(ict, pos));
3396                 return ict;
3397             }
3398 
3399             private TypeSymbol makeNotionalInterface(IntersectionClassType ict, DiagnosticPosition pos) {
3400                 ListBuffer<Type> targs = new ListBuffer<>();
3401                 ListBuffer<Type> supertypes = new ListBuffer<>();
3402                 for (Type i : ict.interfaces_field) {
3403                     if (i.isParameterized()) {
3404                         targs.appendList(i.tsym.type.allparams());
3405                     }
3406                     supertypes.append(i.tsym.type);
3407                 }
3408                 IntersectionClassType notionalIntf = types.makeIntersectionType(supertypes.toList());
3409                 notionalIntf.allparams_field = targs.toList();
3410                 notionalIntf.tsym.flags_field |= INTERFACE;
3411                 return notionalIntf.tsym;
3412             }
3413         };
3414 
3415         private Type fallbackDescriptorType(JCExpression tree) {
3416             switch (tree.getTag()) {
3417                 case LAMBDA:
3418                     JCLambda lambda = (JCLambda)tree;
3419                     List<Type> argtypes = List.nil();
3420                     for (JCVariableDecl param : lambda.params) {
3421                         argtypes = param.vartype != null && param.vartype.type != null ?
3422                                 argtypes.append(param.vartype.type) :
3423                                 argtypes.append(syms.errType);
3424                     }
3425                     return new MethodType(argtypes, Type.recoveryType,
3426                             List.of(syms.throwableType), syms.methodClass);
3427                 case REFERENCE:
3428                     return new MethodType(List.nil(), Type.recoveryType,
3429                             List.of(syms.throwableType), syms.methodClass);
3430                 default:
3431                     Assert.error("Cannot get here!");
3432             }
3433             return null;
3434         }
3435 
3436         private void checkAccessibleTypes(final DiagnosticPosition pos, final Env<AttrContext> env,
3437                 final InferenceContext inferenceContext, final Type... ts) {
3438             checkAccessibleTypes(pos, env, inferenceContext, List.from(ts));
3439         }
3440 
3441         private void checkAccessibleTypes(final DiagnosticPosition pos, final Env<AttrContext> env,
3442                 final InferenceContext inferenceContext, final List<Type> ts) {
3443             if (inferenceContext.free(ts)) {
3444                 inferenceContext.addFreeTypeListener(ts,
3445                         solvedContext -> checkAccessibleTypes(pos, env, solvedContext, solvedContext.asInstTypes(ts)));
3446             } else {
3447                 for (Type t : ts) {
3448                     rs.checkAccessibleType(env, t);
3449                 }
3450             }
3451         }
3452 
3453         /**
3454          * Lambda/method reference have a special check context that ensures
3455          * that i.e. a lambda return type is compatible with the expected
3456          * type according to both the inherited context and the assignment
3457          * context.
3458          */
3459         class FunctionalReturnContext extends Check.NestedCheckContext {
3460 
3461             FunctionalReturnContext(CheckContext enclosingContext) {
3462                 super(enclosingContext);
3463             }
3464 
3465             @Override
3466             public boolean compatible(Type found, Type req, Warner warn) {
3467                 //return type must be compatible in both current context and assignment context
3468                 return chk.basicHandler.compatible(inferenceContext().asUndetVar(found), inferenceContext().asUndetVar(req), warn);
3469             }
3470 
3471             @Override
3472             public void report(DiagnosticPosition pos, JCDiagnostic details) {
3473                 enclosingContext.report(pos, diags.fragment(Fragments.IncompatibleRetTypeInLambda(details)));
3474             }
3475         }
3476 
3477         class ExpressionLambdaReturnContext extends FunctionalReturnContext {
3478 
3479             JCExpression expr;
3480             boolean expStmtExpected;
3481 
3482             ExpressionLambdaReturnContext(JCExpression expr, CheckContext enclosingContext) {
3483                 super(enclosingContext);
3484                 this.expr = expr;
3485             }
3486 
3487             @Override
3488             public void report(DiagnosticPosition pos, JCDiagnostic details) {
3489                 if (expStmtExpected) {
3490                     enclosingContext.report(pos, diags.fragment(Fragments.StatExprExpected));
3491                 } else {
3492                     super.report(pos, details);
3493                 }
3494             }
3495 
3496             @Override
3497             public boolean compatible(Type found, Type req, Warner warn) {
3498                 //a void return is compatible with an expression statement lambda
3499                 if (req.hasTag(VOID)) {
3500                     expStmtExpected = true;
3501                     return TreeInfo.isExpressionStatement(expr);
3502                 } else {
3503                     return super.compatible(found, req, warn);
3504                 }
3505             }
3506         }
3507 
3508         ResultInfo lambdaBodyResult(JCLambda that, Type descriptor, ResultInfo resultInfo) {
3509             FunctionalReturnContext funcContext = that.getBodyKind() == JCLambda.BodyKind.EXPRESSION ?
3510                     new ExpressionLambdaReturnContext((JCExpression)that.getBody(), resultInfo.checkContext) :
3511                     new FunctionalReturnContext(resultInfo.checkContext);
3512 
3513             return descriptor.getReturnType() == Type.recoveryType ?
3514                     recoveryInfo :
3515                     new ResultInfo(KindSelector.VAL,
3516                             descriptor.getReturnType(), funcContext);
3517         }
3518 
3519         /**
3520         * Lambda compatibility. Check that given return types, thrown types, parameter types
3521         * are compatible with the expected functional interface descriptor. This means that:
3522         * (i) parameter types must be identical to those of the target descriptor; (ii) return
3523         * types must be compatible with the return type of the expected descriptor.
3524         */
3525         void checkLambdaCompatible(JCLambda tree, Type descriptor, CheckContext checkContext) {
3526             Type returnType = checkContext.inferenceContext().asUndetVar(descriptor.getReturnType());
3527 
3528             //return values have already been checked - but if lambda has no return
3529             //values, we must ensure that void/value compatibility is correct;
3530             //this amounts at checking that, if a lambda body can complete normally,
3531             //the descriptor's return type must be void
3532             if (tree.getBodyKind() == JCLambda.BodyKind.STATEMENT && tree.canCompleteNormally &&
3533                     !returnType.hasTag(VOID) && returnType != Type.recoveryType) {
3534                 Fragment msg =
3535                         Fragments.IncompatibleRetTypeInLambda(Fragments.MissingRetVal(returnType));
3536                 checkContext.report(tree,
3537                                     diags.fragment(msg));
3538             }
3539 
3540             List<Type> argTypes = checkContext.inferenceContext().asUndetVars(descriptor.getParameterTypes());
3541             if (!types.isSameTypes(argTypes, TreeInfo.types(tree.params))) {
3542                 checkContext.report(tree, diags.fragment(Fragments.IncompatibleArgTypesInLambda));
3543             }
3544         }
3545 
3546         /* Map to hold 'fake' clinit methods. If a lambda is used to initialize a
3547          * static field and that lambda has type annotations, these annotations will
3548          * also be stored at these fake clinit methods.
3549          *
3550          * LambdaToMethod also use fake clinit methods so they can be reused.
3551          * Also as LTM is a phase subsequent to attribution, the methods from
3552          * clinits can be safely removed by LTM to save memory.
3553          */
3554         private Map<ClassSymbol, MethodSymbol> clinits = new HashMap<>();
3555 
3556         public MethodSymbol removeClinit(ClassSymbol sym) {
3557             return clinits.remove(sym);
3558         }
3559 
3560         /* This method returns an environment to be used to attribute a lambda
3561          * expression.
3562          *
3563          * The owner of this environment is a method symbol. If the current owner
3564          * is not a method, for example if the lambda is used to initialize
3565          * a field, then if the field is:
3566          *
3567          * - an instance field, we use the first constructor.
3568          * - a static field, we create a fake clinit method.
3569          */
3570         public Env<AttrContext> lambdaEnv(JCLambda that, Env<AttrContext> env) {
3571             Env<AttrContext> lambdaEnv;
3572             Symbol owner = env.info.scope.owner;
3573             if (owner.kind == VAR && owner.owner.kind == TYP) {
3574                 //field initializer
3575                 ClassSymbol enclClass = owner.enclClass();
3576                 Symbol newScopeOwner = env.info.scope.owner;
3577                 /* if the field isn't static, then we can get the first constructor
3578                  * and use it as the owner of the environment. This is what
3579                  * LTM code is doing to look for type annotations so we are fine.
3580                  */
3581                 if ((owner.flags() & STATIC) == 0) {
3582                     for (Symbol s : enclClass.members_field.getSymbolsByName(names.init)) {
3583                         newScopeOwner = s;
3584                         break;
3585                     }
3586                 } else {
3587                     /* if the field is static then we need to create a fake clinit
3588                      * method, this method can later be reused by LTM.
3589                      */
3590                     MethodSymbol clinit = clinits.get(enclClass);
3591                     if (clinit == null) {
3592                         Type clinitType = new MethodType(List.nil(),
3593                                 syms.voidType, List.nil(), syms.methodClass);
3594                         clinit = new MethodSymbol(STATIC | SYNTHETIC | PRIVATE,
3595                                 names.clinit, clinitType, enclClass);
3596                         clinit.params = List.nil();
3597                         clinits.put(enclClass, clinit);
3598                     }
3599                     newScopeOwner = clinit;
3600                 }
3601                 lambdaEnv = env.dup(that, env.info.dup(env.info.scope.dupUnshared(newScopeOwner)));
3602             } else {
3603                 lambdaEnv = env.dup(that, env.info.dup(env.info.scope.dup()));
3604             }
3605             lambdaEnv.info.yieldResult = null;
3606             lambdaEnv.info.isLambda = true;
3607             return lambdaEnv;
3608         }
3609 
3610     @Override
3611     public void visitReference(final JCMemberReference that) {
3612         if (pt().isErroneous() || (pt().hasTag(NONE) && pt() != Type.recoveryType)) {
3613             if (pt().hasTag(NONE) && (env.info.enclVar == null || !env.info.enclVar.type.isErroneous())) {
3614                 //method reference only allowed in assignment or method invocation/cast context
3615                 log.error(that.pos(), Errors.UnexpectedMref);
3616             }
3617             result = that.type = types.createErrorType(pt());
3618             return;
3619         }
3620         final Env<AttrContext> localEnv = env.dup(that);
3621         try {
3622             //attribute member reference qualifier - if this is a constructor
3623             //reference, the expected kind must be a type
3624             Type exprType = attribTree(that.expr, env, memberReferenceQualifierResult(that));
3625 
3626             if (that.getMode() == JCMemberReference.ReferenceMode.NEW) {
3627                 exprType = chk.checkConstructorRefType(that.expr, exprType);
3628                 if (!exprType.isErroneous() &&
3629                     exprType.isRaw() &&
3630                     that.typeargs != null) {
3631                     log.error(that.expr.pos(),
3632                               Errors.InvalidMref(Kinds.kindName(that.getMode()),
3633                                                  Fragments.MrefInferAndExplicitParams));
3634                     exprType = types.createErrorType(exprType);
3635                 }
3636             }
3637 
3638             if (exprType.isErroneous()) {
3639                 //if the qualifier expression contains problems,
3640                 //give up attribution of method reference
3641                 result = that.type = exprType;
3642                 return;
3643             }
3644 
3645             if (TreeInfo.isStaticSelector(that.expr, names)) {
3646                 //if the qualifier is a type, validate it; raw warning check is
3647                 //omitted as we don't know at this stage as to whether this is a
3648                 //raw selector (because of inference)
3649                 chk.validate(that.expr, env, false);
3650             } else {
3651                 Symbol lhsSym = TreeInfo.symbol(that.expr);
3652                 localEnv.info.selectSuper = lhsSym != null && lhsSym.name == names._super;
3653             }
3654             //attrib type-arguments
3655             List<Type> typeargtypes = List.nil();
3656             if (that.typeargs != null) {
3657                 typeargtypes = attribTypes(that.typeargs, localEnv);
3658             }
3659 
3660             boolean isTargetSerializable =
3661                     resultInfo.checkContext.deferredAttrContext().mode == DeferredAttr.AttrMode.CHECK &&
3662                     rs.isSerializable(pt());
3663             TargetInfo targetInfo = getTargetInfo(that, resultInfo, null);
3664             Type currentTarget = targetInfo.target;
3665             Type desc = targetInfo.descriptor;
3666 
3667             setFunctionalInfo(localEnv, that, pt(), desc, currentTarget, resultInfo.checkContext);
3668             List<Type> argtypes = desc.getParameterTypes();
3669             Resolve.MethodCheck referenceCheck = rs.resolveMethodCheck;
3670 
3671             if (resultInfo.checkContext.inferenceContext().free(argtypes)) {
3672                 referenceCheck = rs.new MethodReferenceCheck(resultInfo.checkContext.inferenceContext());
3673             }
3674 
3675             Pair<Symbol, Resolve.ReferenceLookupHelper> refResult = null;
3676             List<Type> saved_undet = resultInfo.checkContext.inferenceContext().save();
3677             try {
3678                 refResult = rs.resolveMemberReference(localEnv, that, that.expr.type,
3679                         that.name, argtypes, typeargtypes, targetInfo.descriptor, referenceCheck,
3680                         resultInfo.checkContext.inferenceContext(), rs.basicReferenceChooser);
3681             } finally {
3682                 resultInfo.checkContext.inferenceContext().rollback(saved_undet);
3683             }
3684 
3685             Symbol refSym = refResult.fst;
3686             Resolve.ReferenceLookupHelper lookupHelper = refResult.snd;
3687 
3688             /** this switch will need to go away and be replaced by the new RESOLUTION_TARGET testing
3689              *  JDK-8075541
3690              */
3691             if (refSym.kind != MTH) {
3692                 boolean targetError;
3693                 switch (refSym.kind) {
3694                     case ABSENT_MTH:
3695                     case MISSING_ENCL:
3696                         targetError = false;
3697                         break;
3698                     case WRONG_MTH:
3699                     case WRONG_MTHS:
3700                     case AMBIGUOUS:
3701                     case HIDDEN:
3702                     case STATICERR:
3703                         targetError = true;
3704                         break;
3705                     default:
3706                         Assert.error("unexpected result kind " + refSym.kind);
3707                         targetError = false;
3708                 }
3709 
3710                 JCDiagnostic detailsDiag = ((Resolve.ResolveError)refSym.baseSymbol())
3711                         .getDiagnostic(JCDiagnostic.DiagnosticType.FRAGMENT,
3712                                 that, exprType.tsym, exprType, that.name, argtypes, typeargtypes);
3713 
3714                 JCDiagnostic diag = diags.create(log.currentSource(), that,
3715                         targetError ?
3716                             Fragments.InvalidMref(Kinds.kindName(that.getMode()), detailsDiag) :
3717                             Errors.InvalidMref(Kinds.kindName(that.getMode()), detailsDiag));
3718 
3719                 if (targetError && currentTarget == Type.recoveryType) {
3720                     //a target error doesn't make sense during recovery stage
3721                     //as we don't know what actual parameter types are
3722                     result = that.type = currentTarget;
3723                     return;
3724                 } else {
3725                     if (targetError) {
3726                         resultInfo.checkContext.report(that, diag);
3727                     } else {
3728                         log.report(diag);
3729                     }
3730                     result = that.type = types.createErrorType(currentTarget);
3731                     return;
3732                 }
3733             }
3734 
3735             that.sym = refSym.isConstructor() ? refSym.baseSymbol() : refSym;
3736             that.kind = lookupHelper.referenceKind(that.sym);
3737             that.ownerAccessible = rs.isAccessible(localEnv, that.sym.enclClass());
3738 
3739             if (desc.getReturnType() == Type.recoveryType) {
3740                 // stop here
3741                 result = that.type = currentTarget;
3742                 return;
3743             }
3744 
3745             if (!env.info.attributionMode.isSpeculative && that.getMode() == JCMemberReference.ReferenceMode.NEW) {
3746                 Type enclosingType = exprType.getEnclosingType();
3747                 if (enclosingType != null && enclosingType.hasTag(CLASS)) {
3748                     // Check for the existence of an appropriate outer instance
3749                     rs.resolveImplicitThis(that.pos(), env, exprType);
3750                 }
3751             }
3752 
3753             if (resultInfo.checkContext.deferredAttrContext().mode == AttrMode.CHECK) {
3754 
3755                 if (that.getMode() == ReferenceMode.INVOKE &&
3756                         TreeInfo.isStaticSelector(that.expr, names) &&
3757                         that.kind.isUnbound() &&
3758                         lookupHelper.site.isRaw()) {
3759                     chk.checkRaw(that.expr, localEnv);
3760                 }
3761 
3762                 if (that.sym.isStatic() && TreeInfo.isStaticSelector(that.expr, names) &&
3763                         exprType.getTypeArguments().nonEmpty()) {
3764                     //static ref with class type-args
3765                     log.error(that.expr.pos(),
3766                               Errors.InvalidMref(Kinds.kindName(that.getMode()),
3767                                                  Fragments.StaticMrefWithTargs));
3768                     result = that.type = types.createErrorType(currentTarget);
3769                     return;
3770                 }
3771 
3772                 if (!refSym.isStatic() && that.kind == JCMemberReference.ReferenceKind.SUPER) {
3773                     // Check that super-qualified symbols are not abstract (JLS)
3774                     rs.checkNonAbstract(that.pos(), that.sym);
3775                 }
3776 
3777                 if (isTargetSerializable) {
3778                     chk.checkAccessFromSerializableElement(that, true);
3779                 }
3780             }
3781 
3782             ResultInfo checkInfo =
3783                     resultInfo.dup(newMethodTemplate(
3784                         desc.getReturnType().hasTag(VOID) ? Type.noType : desc.getReturnType(),
3785                         that.kind.isUnbound() ? argtypes.tail : argtypes, typeargtypes),
3786                         new FunctionalReturnContext(resultInfo.checkContext), CheckMode.NO_TREE_UPDATE);
3787 
3788             Type refType = checkId(that, lookupHelper.site, refSym, localEnv, checkInfo);
3789 
3790             if (that.kind.isUnbound() &&
3791                     resultInfo.checkContext.inferenceContext().free(argtypes.head)) {
3792                 //re-generate inference constraints for unbound receiver
3793                 if (!types.isSubtype(resultInfo.checkContext.inferenceContext().asUndetVar(argtypes.head), exprType)) {
3794                     //cannot happen as this has already been checked - we just need
3795                     //to regenerate the inference constraints, as that has been lost
3796                     //as a result of the call to inferenceContext.save()
3797                     Assert.error("Can't get here");
3798                 }
3799             }
3800 
3801             if (!refType.isErroneous()) {
3802                 refType = types.createMethodTypeWithReturn(refType,
3803                         adjustMethodReturnType(refSym, lookupHelper.site, that.name, checkInfo.pt.getParameterTypes(), refType.getReturnType()));
3804             }
3805 
3806             //go ahead with standard method reference compatibility check - note that param check
3807             //is a no-op (as this has been taken care during method applicability)
3808             boolean isSpeculativeRound =
3809                     resultInfo.checkContext.deferredAttrContext().mode == DeferredAttr.AttrMode.SPECULATIVE;
3810 
3811             that.type = currentTarget; //avoids recovery at this stage
3812             checkReferenceCompatible(that, desc, refType, resultInfo.checkContext, isSpeculativeRound);
3813             if (!isSpeculativeRound) {
3814                 checkAccessibleTypes(that, localEnv, resultInfo.checkContext.inferenceContext(), desc, currentTarget);
3815             }
3816             result = check(that, currentTarget, KindSelector.VAL, resultInfo);
3817         } catch (Types.FunctionDescriptorLookupError ex) {
3818             JCDiagnostic cause = ex.getDiagnostic();
3819             resultInfo.checkContext.report(that, cause);
3820             result = that.type = types.createErrorType(pt());
3821             return;
3822         }
3823     }
3824     //where
3825         ResultInfo memberReferenceQualifierResult(JCMemberReference tree) {
3826             //if this is a constructor reference, the expected kind must be a type
3827             return new ResultInfo(tree.getMode() == ReferenceMode.INVOKE ?
3828                                   KindSelector.VAL_TYP : KindSelector.TYP,
3829                                   Type.noType);
3830         }
3831 
3832 
3833     @SuppressWarnings("fallthrough")
3834     void checkReferenceCompatible(JCMemberReference tree, Type descriptor, Type refType, CheckContext checkContext, boolean speculativeAttr) {
3835         InferenceContext inferenceContext = checkContext.inferenceContext();
3836         Type returnType = inferenceContext.asUndetVar(descriptor.getReturnType());
3837 
3838         Type resType;
3839         switch (tree.getMode()) {
3840             case NEW:
3841                 if (!tree.expr.type.isRaw()) {
3842                     resType = tree.expr.type;
3843                     break;
3844                 }
3845             default:
3846                 resType = refType.getReturnType();
3847         }
3848 
3849         Type incompatibleReturnType = resType;
3850 
3851         if (returnType.hasTag(VOID)) {
3852             incompatibleReturnType = null;
3853         }
3854 
3855         if (!returnType.hasTag(VOID) && !resType.hasTag(VOID)) {
3856             if (resType.isErroneous() ||
3857                     new FunctionalReturnContext(checkContext).compatible(resType, returnType,
3858                             checkContext.checkWarner(tree, resType, returnType))) {
3859                 incompatibleReturnType = null;
3860             }
3861         }
3862 
3863         if (incompatibleReturnType != null) {
3864             Fragment msg =
3865                     Fragments.IncompatibleRetTypeInMref(Fragments.InconvertibleTypes(resType, descriptor.getReturnType()));
3866             checkContext.report(tree, diags.fragment(msg));
3867         } else {
3868             if (inferenceContext.free(refType)) {
3869                 // we need to wait for inference to finish and then replace inference vars in the referent type
3870                 inferenceContext.addFreeTypeListener(List.of(refType),
3871                         instantiatedContext -> {
3872                             tree.referentType = instantiatedContext.asInstType(refType);
3873                         });
3874             } else {
3875                 tree.referentType = refType;
3876             }
3877         }
3878 
3879         if (!speculativeAttr) {
3880             if (!checkExConstraints(refType.getThrownTypes(), descriptor.getThrownTypes(), inferenceContext)) {
3881                 log.error(tree, Errors.IncompatibleThrownTypesInMref(refType.getThrownTypes()));
3882             }
3883         }
3884     }
3885 
3886     boolean checkExConstraints(
3887             List<Type> thrownByFuncExpr,
3888             List<Type> thrownAtFuncType,
3889             InferenceContext inferenceContext) {
3890         /** 18.2.5: Otherwise, let E1, ..., En be the types in the function type's throws clause that
3891          *  are not proper types
3892          */
3893         List<Type> nonProperList = thrownAtFuncType.stream()
3894                 .filter(e -> inferenceContext.free(e)).collect(List.collector());
3895         List<Type> properList = thrownAtFuncType.diff(nonProperList);
3896 
3897         /** Let X1,...,Xm be the checked exception types that the lambda body can throw or
3898          *  in the throws clause of the invocation type of the method reference's compile-time
3899          *  declaration
3900          */
3901         List<Type> checkedList = thrownByFuncExpr.stream()
3902                 .filter(e -> chk.isChecked(e)).collect(List.collector());
3903 
3904         /** If n = 0 (the function type's throws clause consists only of proper types), then
3905          *  if there exists some i (1 <= i <= m) such that Xi is not a subtype of any proper type
3906          *  in the throws clause, the constraint reduces to false; otherwise, the constraint
3907          *  reduces to true
3908          */
3909         ListBuffer<Type> uncaughtByProperTypes = new ListBuffer<>();
3910         for (Type checked : checkedList) {
3911             boolean isSubtype = false;
3912             for (Type proper : properList) {
3913                 if (types.isSubtype(checked, proper)) {
3914                     isSubtype = true;
3915                     break;
3916                 }
3917             }
3918             if (!isSubtype) {
3919                 uncaughtByProperTypes.add(checked);
3920             }
3921         }
3922 
3923         if (nonProperList.isEmpty() && !uncaughtByProperTypes.isEmpty()) {
3924             return false;
3925         }
3926 
3927         /** If n > 0, the constraint reduces to a set of subtyping constraints:
3928          *  for all i (1 <= i <= m), if Xi is not a subtype of any proper type in the
3929          *  throws clause, then the constraints include, for all j (1 <= j <= n), <Xi <: Ej>
3930          */
3931         List<Type> nonProperAsUndet = inferenceContext.asUndetVars(nonProperList);
3932         uncaughtByProperTypes.forEach(checkedEx -> {
3933             nonProperAsUndet.forEach(nonProper -> {
3934                 types.isSubtype(checkedEx, nonProper);
3935             });
3936         });
3937 
3938         /** In addition, for all j (1 <= j <= n), the constraint reduces to the bound throws Ej
3939          */
3940         nonProperAsUndet.stream()
3941                 .filter(t -> t.hasTag(UNDETVAR))
3942                 .forEach(t -> ((UndetVar)t).setThrow());
3943         return true;
3944     }
3945 
3946     /**
3947      * Set functional type info on the underlying AST. Note: as the target descriptor
3948      * might contain inference variables, we might need to register an hook in the
3949      * current inference context.
3950      */
3951     private void setFunctionalInfo(final Env<AttrContext> env, final JCFunctionalExpression fExpr,
3952             final Type pt, final Type descriptorType, final Type primaryTarget, final CheckContext checkContext) {
3953         if (checkContext.inferenceContext().free(descriptorType)) {
3954             checkContext.inferenceContext().addFreeTypeListener(List.of(pt, descriptorType),
3955                     inferenceContext -> setFunctionalInfo(env, fExpr, pt, inferenceContext.asInstType(descriptorType),
3956                     inferenceContext.asInstType(primaryTarget), checkContext));
3957         } else {
3958             if (pt.hasTag(CLASS)) {
3959                 fExpr.target = primaryTarget;
3960             }
3961             if (checkContext.deferredAttrContext().mode == DeferredAttr.AttrMode.CHECK &&
3962                     pt != Type.recoveryType) {
3963                 //check that functional interface class is well-formed
3964                 try {
3965                     /* Types.makeFunctionalInterfaceClass() may throw an exception
3966                      * when it's executed post-inference. See the listener code
3967                      * above.
3968                      */
3969                     ClassSymbol csym = types.makeFunctionalInterfaceClass(env,
3970                             names.empty, fExpr.target, ABSTRACT);
3971                     if (csym != null) {
3972                         chk.checkImplementations(env.tree, csym, csym);
3973                         try {
3974                             //perform an additional functional interface check on the synthetic class,
3975                             //as there may be spurious errors for raw targets - because of existing issues
3976                             //with membership and inheritance (see JDK-8074570).
3977                             csym.flags_field |= INTERFACE;
3978                             types.findDescriptorType(csym.type);
3979                         } catch (FunctionDescriptorLookupError err) {
3980                             resultInfo.checkContext.report(fExpr,
3981                                     diags.fragment(Fragments.NoSuitableFunctionalIntfInst(fExpr.target)));
3982                         }
3983                     }
3984                 } catch (Types.FunctionDescriptorLookupError ex) {
3985                     JCDiagnostic cause = ex.getDiagnostic();
3986                     resultInfo.checkContext.report(env.tree, cause);
3987                 }
3988             }
3989         }
3990     }
3991 
3992     public void visitParens(JCParens tree) {
3993         Type owntype = attribTree(tree.expr, env, resultInfo);
3994         result = check(tree, owntype, pkind(), resultInfo);
3995         Symbol sym = TreeInfo.symbol(tree);
3996         if (sym != null && sym.kind.matches(KindSelector.TYP_PCK) && sym.kind != Kind.ERR)
3997             log.error(tree.pos(), Errors.IllegalParenthesizedExpression);
3998     }
3999 
4000     public void visitAssign(JCAssign tree) {
4001         Type owntype = attribTree(tree.lhs, env.dup(tree), varAssignmentInfo);
4002         Type capturedType = capture(owntype);
4003         attribExpr(tree.rhs, env, owntype);
4004         result = check(tree, capturedType, KindSelector.VAL, resultInfo);
4005     }
4006 
4007     public void visitAssignop(JCAssignOp tree) {
4008         // Attribute arguments.
4009         Type owntype = attribTree(tree.lhs, env, varAssignmentInfo);
4010         Type operand = attribExpr(tree.rhs, env);
4011         // Find operator.
4012         Symbol operator = tree.operator = operators.resolveBinary(tree, tree.getTag().noAssignOp(), owntype, operand);
4013         if (operator != operators.noOpSymbol &&
4014                 !owntype.isErroneous() &&
4015                 !operand.isErroneous()) {
4016             chk.checkDivZero(tree.rhs.pos(), operator, operand);
4017             chk.checkCastable(tree.rhs.pos(),
4018                               operator.type.getReturnType(),
4019                               owntype);
4020         }
4021         result = check(tree, owntype, KindSelector.VAL, resultInfo);
4022     }
4023 
4024     public void visitUnary(JCUnary tree) {
4025         // Attribute arguments.
4026         Type argtype = (tree.getTag().isIncOrDecUnaryOp())
4027             ? attribTree(tree.arg, env, varAssignmentInfo)
4028             : chk.checkNonVoid(tree.arg.pos(), attribExpr(tree.arg, env));
4029 
4030         // Find operator.
4031         OperatorSymbol operator = tree.operator = operators.resolveUnary(tree, tree.getTag(), argtype);
4032         Type owntype = types.createErrorType(tree.type);
4033         if (operator != operators.noOpSymbol &&
4034                 !argtype.isErroneous()) {
4035             owntype = (tree.getTag().isIncOrDecUnaryOp())
4036                 ? tree.arg.type
4037                 : operator.type.getReturnType();
4038             int opc = operator.opcode;
4039 
4040             // If the argument is constant, fold it.
4041             if (argtype.constValue() != null) {
4042                 Type ctype = cfolder.fold1(opc, argtype);
4043                 if (ctype != null) {
4044                     owntype = cfolder.coerce(ctype, owntype);
4045                 }
4046             }
4047         }
4048         result = check(tree, owntype, KindSelector.VAL, resultInfo);
4049         matchBindings = matchBindingsComputer.unary(tree, matchBindings);
4050     }
4051 
4052     public void visitBinary(JCBinary tree) {
4053         // Attribute arguments.
4054         Type left = chk.checkNonVoid(tree.lhs.pos(), attribExpr(tree.lhs, env));
4055         // x && y
4056         // include x's bindings when true in y
4057 
4058         // x || y
4059         // include x's bindings when false in y
4060 
4061         MatchBindings lhsBindings = matchBindings;
4062         List<BindingSymbol> propagatedBindings;
4063         switch (tree.getTag()) {
4064             case AND:
4065                 propagatedBindings = lhsBindings.bindingsWhenTrue;
4066                 break;
4067             case OR:
4068                 propagatedBindings = lhsBindings.bindingsWhenFalse;
4069                 break;
4070             default:
4071                 propagatedBindings = List.nil();
4072                 break;
4073         }
4074         Env<AttrContext> rhsEnv = bindingEnv(env, propagatedBindings);
4075         Type right;
4076         try {
4077             right = chk.checkNonVoid(tree.rhs.pos(), attribExpr(tree.rhs, rhsEnv));
4078         } finally {
4079             rhsEnv.info.scope.leave();
4080         }
4081 
4082         matchBindings = matchBindingsComputer.binary(tree, lhsBindings, matchBindings);
4083 
4084         // Find operator.
4085         OperatorSymbol operator = tree.operator = operators.resolveBinary(tree, tree.getTag(), left, right);
4086         Type owntype = types.createErrorType(tree.type);
4087         if (operator != operators.noOpSymbol &&
4088                 !left.isErroneous() &&
4089                 !right.isErroneous()) {
4090             owntype = operator.type.getReturnType();
4091             int opc = operator.opcode;
4092             // If both arguments are constants, fold them.
4093             if (left.constValue() != null && right.constValue() != null) {
4094                 Type ctype = cfolder.fold2(opc, left, right);
4095                 if (ctype != null) {
4096                     owntype = cfolder.coerce(ctype, owntype);
4097                 }
4098             }
4099 
4100             // Check that argument types of a reference ==, != are
4101             // castable to each other, (JLS 15.21).  Note: unboxing
4102             // comparisons will not have an acmp* opc at this point.
4103             if ((opc == ByteCodes.if_acmpeq || opc == ByteCodes.if_acmpne)) {
4104                 if (!types.isCastable(left, right, new Warner(tree.pos()))) {
4105                     log.error(tree.pos(), Errors.IncomparableTypes(left, right));
4106                 }
4107                 chk.checkForSuspectClassLiteralComparison(tree, left, right);
4108             }
4109 
4110             chk.checkDivZero(tree.rhs.pos(), operator, right);
4111         }
4112         result = check(tree, owntype, KindSelector.VAL, resultInfo);
4113     }
4114 
4115     public void visitTypeCast(final JCTypeCast tree) {
4116         Type clazztype = attribType(tree.clazz, env);
4117         chk.validate(tree.clazz, env, false);
4118         //a fresh environment is required for 292 inference to work properly ---
4119         //see Infer.instantiatePolymorphicSignatureInstance()
4120         Env<AttrContext> localEnv = env.dup(tree);
4121         //should we propagate the target type?
4122         final ResultInfo castInfo;
4123         JCExpression expr = TreeInfo.skipParens(tree.expr);
4124         boolean isPoly = allowPoly && (expr.hasTag(LAMBDA) || expr.hasTag(REFERENCE));
4125         if (isPoly) {
4126             //expression is a poly - we need to propagate target type info
4127             castInfo = new ResultInfo(KindSelector.VAL, clazztype,
4128                                       new Check.NestedCheckContext(resultInfo.checkContext) {
4129                 @Override
4130                 public boolean compatible(Type found, Type req, Warner warn) {
4131                     return types.isCastable(found, req, warn);
4132                 }
4133             });
4134         } else {
4135             //standalone cast - target-type info is not propagated
4136             castInfo = unknownExprInfo;
4137         }
4138         Type exprtype = attribTree(tree.expr, localEnv, castInfo);
4139         Type owntype = isPoly ? clazztype : chk.checkCastable(tree.expr.pos(), exprtype, clazztype);
4140         if (exprtype.constValue() != null)
4141             owntype = cfolder.coerce(exprtype, owntype);
4142         result = check(tree, capture(owntype), KindSelector.VAL, resultInfo);
4143         if (!isPoly)
4144             chk.checkRedundantCast(localEnv, tree);
4145     }
4146 
4147     public void visitTypeTest(JCInstanceOf tree) {
4148         Type exprtype = chk.checkNullOrRefType(
4149                 tree.expr.pos(), attribExpr(tree.expr, env));
4150         Type clazztype;
4151         JCTree typeTree;
4152         if (tree.pattern.getTag() == BINDINGPATTERN ||
4153            tree.pattern.getTag() == PARENTHESIZEDPATTERN) {
4154             attribTree(tree.pattern, env, unknownExprInfo);
4155             clazztype = tree.pattern.type;
4156             if (types.isSubtype(exprtype, clazztype) &&
4157                 !exprtype.isErroneous() && !clazztype.isErroneous()) {
4158                 log.error(tree.pos(), Errors.InstanceofPatternNoSubtype(exprtype, clazztype));
4159             }
4160             typeTree = TreeInfo.primaryPatternTree((JCPattern) tree.pattern).var.vartype;
4161         } else {
4162             clazztype = attribType(tree.pattern, env);
4163             typeTree = tree.pattern;
4164             chk.validate(typeTree, env, false);
4165         }
4166         if (!clazztype.hasTag(TYPEVAR)) {
4167             clazztype = chk.checkClassOrArrayType(typeTree.pos(), clazztype);
4168         }
4169         if (!clazztype.isErroneous() && !types.isReifiable(clazztype)) {
4170             boolean valid = false;
4171             if (allowReifiableTypesInInstanceof) {
4172                 valid = checkCastablePattern(tree.expr.pos(), exprtype, clazztype);
4173             } else {
4174                 log.error(DiagnosticFlag.SOURCE_LEVEL, tree.pos(),
4175                           Feature.REIFIABLE_TYPES_INSTANCEOF.error(this.sourceName));
4176                 allowReifiableTypesInInstanceof = true;
4177             }
4178             if (!valid) {
4179                 clazztype = types.createErrorType(clazztype);
4180             }
4181         }
4182         chk.checkCastable(tree.expr.pos(), exprtype, clazztype);
4183         result = check(tree, syms.booleanType, KindSelector.VAL, resultInfo);
4184     }
4185 
4186     private boolean checkCastablePattern(DiagnosticPosition pos,
4187                                          Type exprType,
4188                                          Type pattType) {
4189         Warner warner = new Warner();
4190         if (!types.isCastable(exprType, pattType, warner)) {
4191             chk.basicHandler.report(pos,
4192                     diags.fragment(Fragments.InconvertibleTypes(exprType, pattType)));
4193             return false;
4194         } else if (warner.hasLint(LintCategory.UNCHECKED)) {
4195             log.error(pos,
4196                     Errors.InstanceofReifiableNotSafe(exprType, pattType));
4197             return false;
4198         } else {
4199             return true;
4200         }
4201     }
4202 
4203     public void visitBindingPattern(JCBindingPattern tree) {
4204         ResultInfo varInfo = new ResultInfo(KindSelector.TYP, resultInfo.pt, resultInfo.checkContext);
4205         tree.type = tree.var.type = attribTree(tree.var.vartype, env, varInfo);
4206         BindingSymbol v = new BindingSymbol(tree.var.mods.flags, tree.var.name, tree.var.vartype.type, env.info.scope.owner);
4207         v.pos = tree.pos;
4208         tree.var.sym = v;
4209         if (chk.checkUnique(tree.var.pos(), v, env.info.scope)) {
4210             chk.checkTransparentVar(tree.var.pos(), v, env.info.scope);
4211         }
4212         annotate.annotateLater(tree.var.mods.annotations, env, v, tree.pos());
4213         annotate.queueScanTreeAndTypeAnnotate(tree.var.vartype, env, v, tree.var.pos());
4214         annotate.flush();
4215         chk.validate(tree.var.vartype, env, true);
4216         result = tree.type;
4217         matchBindings = new MatchBindings(List.of(v), List.nil());
4218     }
4219 
4220     @Override
4221     public void visitParenthesizedPattern(JCParenthesizedPattern tree) {
4222         attribExpr(tree.pattern, env);
4223         result = tree.type = tree.pattern.type;
4224     }
4225 
4226     @Override
4227     public void visitGuardPattern(JCGuardPattern tree) {
4228         attribExpr(tree.patt, env);
4229         MatchBindings afterPattern = matchBindings;
4230         Env<AttrContext> bodyEnv = bindingEnv(env, matchBindings.bindingsWhenTrue);
4231         try {
4232             attribExpr(tree.expr, bodyEnv, syms.booleanType);
4233         } finally {
4234             bodyEnv.info.scope.leave();
4235         }
4236         result = tree.type = tree.patt.type;
4237         matchBindings = matchBindingsComputer.guardedPattern(tree, afterPattern, matchBindings);
4238     }
4239 
4240     public void visitIndexed(JCArrayAccess tree) {
4241         Type owntype = types.createErrorType(tree.type);
4242         Type atype = attribExpr(tree.indexed, env);
4243         attribExpr(tree.index, env, syms.intType);
4244         if (types.isArray(atype))
4245             owntype = types.elemtype(atype);
4246         else if (!atype.hasTag(ERROR))
4247             log.error(tree.pos(), Errors.ArrayReqButFound(atype));
4248         if (!pkind().contains(KindSelector.VAL))
4249             owntype = capture(owntype);
4250         result = check(tree, owntype, KindSelector.VAR, resultInfo);
4251     }
4252 
4253     public void visitIdent(JCIdent tree) {
4254         Symbol sym;
4255 
4256         // Find symbol
4257         if (pt().hasTag(METHOD) || pt().hasTag(FORALL)) {
4258             // If we are looking for a method, the prototype `pt' will be a
4259             // method type with the type of the call's arguments as parameters.
4260             env.info.pendingResolutionPhase = null;
4261             sym = rs.resolveMethod(tree.pos(), env, tree.name, pt().getParameterTypes(), pt().getTypeArguments());
4262         } else if (tree.sym != null && tree.sym.kind != VAR) {
4263             sym = tree.sym;
4264         } else {
4265             sym = rs.resolveIdent(tree.pos(), env, tree.name, pkind());
4266         }
4267         tree.sym = sym;
4268 
4269         // Also find the environment current for the class where
4270         // sym is defined (`symEnv').
4271         Env<AttrContext> symEnv = env;
4272         if (env.enclClass.sym.owner.kind != PCK && // we are in an inner class
4273             sym.kind.matches(KindSelector.VAL_MTH) &&
4274             sym.owner.kind == TYP &&
4275             tree.name != names._this && tree.name != names._super) {
4276 
4277             // Find environment in which identifier is defined.
4278             while (symEnv.outer != null &&
4279                    !sym.isMemberOf(symEnv.enclClass.sym, types)) {
4280                 symEnv = symEnv.outer;
4281             }
4282         }
4283 
4284         // If symbol is a variable, ...
4285         if (sym.kind == VAR) {
4286             VarSymbol v = (VarSymbol)sym;
4287 
4288             // ..., evaluate its initializer, if it has one, and check for
4289             // illegal forward reference.
4290             checkInit(tree, env, v, false);
4291 
4292             // If we are expecting a variable (as opposed to a value), check
4293             // that the variable is assignable in the current environment.
4294             if (KindSelector.ASG.subset(pkind()))
4295                 checkAssignable(tree.pos(), v, null, env);
4296         }
4297 
4298         // In a constructor body,
4299         // if symbol is a field or instance method, check that it is
4300         // not accessed before the supertype constructor is called.
4301         if (symEnv.info.isSelfCall &&
4302             sym.kind.matches(KindSelector.VAL_MTH) &&
4303             sym.owner.kind == TYP &&
4304             (sym.flags() & STATIC) == 0) {
4305             chk.earlyRefError(tree.pos(), sym.kind == VAR ?
4306                                           sym : thisSym(tree.pos(), env));
4307         }
4308         Env<AttrContext> env1 = env;
4309         if (sym.kind != ERR && sym.kind != TYP &&
4310             sym.owner != null && sym.owner != env1.enclClass.sym) {
4311             // If the found symbol is inaccessible, then it is
4312             // accessed through an enclosing instance.  Locate this
4313             // enclosing instance:
4314             while (env1.outer != null && !rs.isAccessible(env, env1.enclClass.sym.type, sym))
4315                 env1 = env1.outer;
4316         }
4317 
4318         if (env.info.isSerializable) {
4319             chk.checkAccessFromSerializableElement(tree, env.info.isSerializableLambda);
4320         }
4321 
4322         result = checkId(tree, env1.enclClass.sym.type, sym, env, resultInfo);
4323     }
4324 
4325     public void visitSelect(JCFieldAccess tree) {
4326         // Determine the expected kind of the qualifier expression.
4327         KindSelector skind = KindSelector.NIL;
4328         if (tree.name == names._this || tree.name == names._super ||
4329                 tree.name == names._class)
4330         {
4331             skind = KindSelector.TYP;
4332         } else {
4333             if (pkind().contains(KindSelector.PCK))
4334                 skind = KindSelector.of(skind, KindSelector.PCK);
4335             if (pkind().contains(KindSelector.TYP))
4336                 skind = KindSelector.of(skind, KindSelector.TYP, KindSelector.PCK);
4337             if (pkind().contains(KindSelector.VAL_MTH))
4338                 skind = KindSelector.of(skind, KindSelector.VAL, KindSelector.TYP);
4339         }
4340 
4341         // Attribute the qualifier expression, and determine its symbol (if any).
4342         Type site = attribTree(tree.selected, env, new ResultInfo(skind, Type.noType));
4343         Assert.check(site == tree.selected.type);
4344         if (tree.name == names._class && site.isPrimitiveClass()) {
4345             /* JDK-8269956: Where a reflective (class) literal is needed, the unqualified Point.class is
4346              * always the "primary" mirror - representing the primitive reference runtime type - thereby
4347              * always matching the behavior of Object::getClass
4348              */
4349              if (!tree.selected.hasTag(SELECT) || ((JCFieldAccess) tree.selected).name != names.val) {
4350                  tree.selected.setType(site = site.referenceProjection());
4351              }
4352         }
4353         if (!pkind().contains(KindSelector.TYP_PCK))
4354             site = capture(site); // Capture field access
4355 
4356         // don't allow T.class T[].class, etc
4357         if (skind == KindSelector.TYP) {
4358             Type elt = site;
4359             while (elt.hasTag(ARRAY))
4360                 elt = ((ArrayType)elt).elemtype;
4361             if (elt.hasTag(TYPEVAR)) {
4362                 log.error(tree.pos(), Errors.TypeVarCantBeDeref);
4363                 result = tree.type = types.createErrorType(tree.name, site.tsym, site);
4364                 tree.sym = tree.type.tsym;
4365                 return;
4366             }
4367         }
4368 
4369         // If qualifier symbol is a type or `super', assert `selectSuper'
4370         // for the selection. This is relevant for determining whether
4371         // protected symbols are accessible.
4372         Symbol sitesym = TreeInfo.symbol(tree.selected);
4373 
4374         boolean selectSuperPrev = env.info.selectSuper;
4375         env.info.selectSuper =
4376             sitesym != null &&
4377             sitesym.name == names._super;
4378 
4379         // Determine the symbol represented by the selection.
4380         env.info.pendingResolutionPhase = null;
4381         Symbol sym = selectSym(tree, sitesym, site, env, resultInfo);
4382         if (sym.kind == VAR && sym.name != names._super && env.info.defaultSuperCallSite != null) {
4383             log.error(tree.selected.pos(), Errors.NotEnclClass(site.tsym));
4384             sym = syms.errSymbol;
4385         }
4386         if (sym.exists() && !isType(sym) && pkind().contains(KindSelector.TYP_PCK)) {
4387             site = capture(site);
4388             sym = selectSym(tree, sitesym, site, env, resultInfo);
4389         }
4390         boolean varArgs = env.info.lastResolveVarargs();
4391         tree.sym = sym;
4392 
4393         if (site.hasTag(TYPEVAR) && !isType(sym) && sym.kind != ERR) {
4394             site = types.skipTypeVars(site, true);
4395         }
4396 
4397         // If that symbol is a variable, ...
4398         if (sym.kind == VAR) {
4399             VarSymbol v = (VarSymbol)sym;
4400 
4401             // ..., evaluate its initializer, if it has one, and check for
4402             // illegal forward reference.
4403             checkInit(tree, env, v, true);
4404 
4405             // If we are expecting a variable (as opposed to a value), check
4406             // that the variable is assignable in the current environment.
4407             if (KindSelector.ASG.subset(pkind()))
4408                 checkAssignable(tree.pos(), v, tree.selected, env);
4409         }
4410 
4411         if (sitesym != null &&
4412                 sitesym.kind == VAR &&
4413                 ((VarSymbol)sitesym).isResourceVariable() &&
4414                 sym.kind == MTH &&
4415                 sym.name.equals(names.close) &&
4416                 sym.overrides(syms.autoCloseableClose, sitesym.type.tsym, types, true) &&
4417                 env.info.lint.isEnabled(LintCategory.TRY)) {
4418             log.warning(LintCategory.TRY, tree, Warnings.TryExplicitCloseCall);
4419         }
4420 
4421         // Disallow selecting a type from an expression
4422         if (isType(sym) && (sitesym == null || !sitesym.kind.matches(KindSelector.TYP_PCK))) {
4423             tree.type = check(tree.selected, pt(),
4424                               sitesym == null ?
4425                                       KindSelector.VAL : sitesym.kind.toSelector(),
4426                               new ResultInfo(KindSelector.TYP_PCK, pt()));
4427         }
4428 
4429         if (isType(sitesym)) {
4430             if (sym.name == names._this || sym.name == names._super) {
4431                 // If `C' is the currently compiled class, check that
4432                 // `C.this' does not appear in an explicit call to a constructor
4433                 // also make sure that `super` is not used in constructor invocations
4434                 if (env.info.isSelfCall &&
4435                         ((sym.name == names._this &&
4436                         site.tsym == env.enclClass.sym) ||
4437                         sym.name == names._super && env.info.constructorArgs &&
4438                         (sitesym.isInterface() || site.tsym == env.enclClass.sym))) {
4439                     chk.earlyRefError(tree.pos(), sym);
4440                 }
4441             } else {
4442                 // Check if type-qualified fields or methods are static (JLS)
4443                 if ((sym.flags() & STATIC) == 0 &&
4444                     sym.name != names._super &&
4445                     (sym.kind == VAR || sym.kind == MTH)) {
4446                     rs.accessBase(rs.new StaticError(sym),
4447                               tree.pos(), site, sym.name, true);
4448                 }
4449             }
4450             if (!allowStaticInterfaceMethods && sitesym.isInterface() &&
4451                     sym.isStatic() && sym.kind == MTH) {
4452                 log.error(DiagnosticFlag.SOURCE_LEVEL, tree.pos(), Feature.STATIC_INTERFACE_METHODS_INVOKE.error(sourceName));
4453             }
4454         } else if (sym.kind != ERR &&
4455                    (sym.flags() & STATIC) != 0 &&
4456                    sym.name != names._class) {
4457             // If the qualified item is not a type and the selected item is static, report
4458             // a warning. Make allowance for the class of an array type e.g. Object[].class)
4459             chk.warnStatic(tree, Warnings.StaticNotQualifiedByType(sym.kind.kindName(), sym.owner));
4460         }
4461 
4462         // If we are selecting an instance member via a `super', ...
4463         if (env.info.selectSuper && (sym.flags() & STATIC) == 0) {
4464 
4465             // Check that super-qualified symbols are not abstract (JLS)
4466             rs.checkNonAbstract(tree.pos(), sym);
4467 
4468             if (site.isRaw()) {
4469                 // Determine argument types for site.
4470                 Type site1 = types.asSuper(env.enclClass.sym.type.referenceProjectionOrSelf(), site.tsym);
4471                 if (site1 != null) site = site1;
4472             }
4473         }
4474 
4475         if (env.info.isSerializable) {
4476             chk.checkAccessFromSerializableElement(tree, env.info.isSerializableLambda);
4477         }
4478 
4479         env.info.selectSuper = selectSuperPrev;
4480         result = checkId(tree, site, sym, env, resultInfo);
4481     }
4482     //where
4483         /** Determine symbol referenced by a Select expression,
4484          *
4485          *  @param tree   The select tree.
4486          *  @param site   The type of the selected expression,
4487          *  @param env    The current environment.
4488          *  @param resultInfo The current result.
4489          */
4490         private Symbol selectSym(JCFieldAccess tree,
4491                                  Symbol location,
4492                                  Type site,
4493                                  Env<AttrContext> env,
4494                                  ResultInfo resultInfo) {
4495             DiagnosticPosition pos = tree.pos();
4496             Name name = tree.name;
4497             switch (site.getTag()) {
4498             case PACKAGE:
4499                 return rs.accessBase(
4500                     rs.findIdentInPackage(pos, env, site.tsym, name, resultInfo.pkind),
4501                     pos, location, site, name, true);
4502             case ARRAY:
4503             case CLASS:
4504                 if (resultInfo.pt.hasTag(METHOD) || resultInfo.pt.hasTag(FORALL)) {
4505                     return rs.resolveQualifiedMethod(
4506                         pos, env, location, site, name, resultInfo.pt.getParameterTypes(), resultInfo.pt.getTypeArguments());
4507                 } else if (name == names._this || name == names._super) {
4508                     return rs.resolveSelf(pos, env, site.tsym, name);
4509                 } else if (name == names._class) {
4510                     // In this case, we have already made sure in
4511                     // visitSelect that qualifier expression is a type.
4512                     return syms.getClassField(site, types);
4513                 } else if (site.isPrimitiveClass() && isType(location) && resultInfo.pkind.contains(KindSelector.TYP) && (name == names.ref || name == names.val)) {
4514                     return site.tsym;
4515                 } else {
4516                     // We are seeing a plain identifier as selector.
4517                     Symbol sym = rs.findIdentInType(pos, env, site, name, resultInfo.pkind);
4518                         sym = rs.accessBase(sym, pos, location, site, name, true);
4519                     return sym;
4520                 }
4521             case WILDCARD:
4522                 throw new AssertionError(tree);
4523             case TYPEVAR:
4524                 // Normally, site.getUpperBound() shouldn't be null.
4525                 // It should only happen during memberEnter/attribBase
4526                 // when determining the super type which *must* be
4527                 // done before attributing the type variables.  In
4528                 // other words, we are seeing this illegal program:
4529                 // class B<T> extends A<T.foo> {}
4530                 Symbol sym = (site.getUpperBound() != null)
4531                     ? selectSym(tree, location, capture(site.getUpperBound()), env, resultInfo)
4532                     : null;
4533                 if (sym == null) {
4534                     log.error(pos, Errors.TypeVarCantBeDeref);
4535                     return syms.errSymbol;
4536                 } else {
4537                     Symbol sym2 = (sym.flags() & Flags.PRIVATE) != 0 ?
4538                         rs.new AccessError(env, site, sym) :
4539                                 sym;
4540                     rs.accessBase(sym2, pos, location, site, name, true);
4541                     return sym;
4542                 }
4543             case ERROR:
4544                 // preserve identifier names through errors
4545                 return types.createErrorType(name, site.tsym, site).tsym;
4546             default:
4547                 // The qualifier expression is of a primitive type -- only
4548                 // .class is allowed for these.
4549                 if (name == names._class) {
4550                     // In this case, we have already made sure in Select that
4551                     // qualifier expression is a type.
4552                     return syms.getClassField(site, types);
4553                 } else {
4554                     log.error(pos, Errors.CantDeref(site));
4555                     return syms.errSymbol;
4556                 }
4557             }
4558         }
4559 
4560         /** Determine type of identifier or select expression and check that
4561          *  (1) the referenced symbol is not deprecated
4562          *  (2) the symbol's type is safe (@see checkSafe)
4563          *  (3) if symbol is a variable, check that its type and kind are
4564          *      compatible with the prototype and protokind.
4565          *  (4) if symbol is an instance field of a raw type,
4566          *      which is being assigned to, issue an unchecked warning if its
4567          *      type changes under erasure.
4568          *  (5) if symbol is an instance method of a raw type, issue an
4569          *      unchecked warning if its argument types change under erasure.
4570          *  If checks succeed:
4571          *    If symbol is a constant, return its constant type
4572          *    else if symbol is a method, return its result type
4573          *    otherwise return its type.
4574          *  Otherwise return errType.
4575          *
4576          *  @param tree       The syntax tree representing the identifier
4577          *  @param site       If this is a select, the type of the selected
4578          *                    expression, otherwise the type of the current class.
4579          *  @param sym        The symbol representing the identifier.
4580          *  @param env        The current environment.
4581          *  @param resultInfo    The expected result
4582          */
4583         Type checkId(JCTree tree,
4584                      Type site,
4585                      Symbol sym,
4586                      Env<AttrContext> env,
4587                      ResultInfo resultInfo) {
4588             return (resultInfo.pt.hasTag(FORALL) || resultInfo.pt.hasTag(METHOD)) ?
4589                     checkMethodIdInternal(tree, site, sym, env, resultInfo) :
4590                     checkIdInternal(tree, site, sym, resultInfo.pt, env, resultInfo);
4591         }
4592 
4593         Type checkMethodIdInternal(JCTree tree,
4594                      Type site,
4595                      Symbol sym,
4596                      Env<AttrContext> env,
4597                      ResultInfo resultInfo) {
4598             if (resultInfo.pkind.contains(KindSelector.POLY)) {
4599                 return attrRecover.recoverMethodInvocation(tree, site, sym, env, resultInfo);
4600             } else {
4601                 return checkIdInternal(tree, site, sym, resultInfo.pt, env, resultInfo);
4602             }
4603         }
4604 
4605         Type checkIdInternal(JCTree tree,
4606                      Type site,
4607                      Symbol sym,
4608                      Type pt,
4609                      Env<AttrContext> env,
4610                      ResultInfo resultInfo) {
4611             if (pt.isErroneous()) {
4612                 return types.createErrorType(site);
4613             }
4614             Type owntype; // The computed type of this identifier occurrence.
4615             switch (sym.kind) {
4616             case TYP:
4617                 // For types, the computed type equals the symbol's type,
4618                 // except for three situations:
4619                 owntype = sym.type;
4620                 if (owntype.hasTag(CLASS)) {
4621                     Assert.check(owntype.getFlavor() != Flavor.X_Typeof_X);
4622                     chk.checkForBadAuxiliaryClassAccess(tree.pos(), env, (ClassSymbol)sym);
4623                     Type ownOuter = owntype.getEnclosingType();
4624 
4625                     // (a) If symbol is a primitive class and its reference projection
4626                     // is requested via the .ref notation, then adjust the computed type to
4627                     // reflect this.
4628                     if (owntype.isPrimitiveClass() && tree.hasTag(SELECT) && ((JCFieldAccess) tree).name == names.ref) {
4629                         owntype = new ClassType(owntype.getEnclosingType(), owntype.getTypeArguments(), (TypeSymbol)sym, owntype.getMetadata(), Flavor.L_TypeOf_Q);
4630                     }
4631 
4632                     // (b) If the symbol's type is parameterized, erase it
4633                     // because no type parameters were given.
4634                     // We recover generic outer type later in visitTypeApply.
4635                     if (owntype.tsym.type.getTypeArguments().nonEmpty()) {
4636                         owntype = types.erasure(owntype);
4637                     }
4638 
4639                     // (c) If the symbol's type is an inner class, then
4640                     // we have to interpret its outer type as a superclass
4641                     // of the site type. Example:
4642                     //
4643                     // class Tree<A> { class Visitor { ... } }
4644                     // class PointTree extends Tree<Point> { ... }
4645                     // ...PointTree.Visitor...
4646                     //
4647                     // Then the type of the last expression above is
4648                     // Tree<Point>.Visitor.
4649                     else if (ownOuter.hasTag(CLASS) && site != ownOuter) {
4650                         Type normOuter = site;
4651                         if (normOuter.hasTag(CLASS)) {
4652                             normOuter = types.asEnclosingSuper(site, ownOuter.tsym);
4653                         }
4654                         if (normOuter == null) // perhaps from an import
4655                             normOuter = types.erasure(ownOuter);
4656                         if (normOuter != ownOuter)
4657                             owntype = new ClassType(
4658                                 normOuter, List.nil(), owntype.tsym,
4659                                 owntype.getMetadata(), owntype.getFlavor());
4660                     }
4661                 }
4662                 break;
4663             case VAR:
4664                 VarSymbol v = (VarSymbol)sym;
4665 
4666                 if (env.info.enclVar != null
4667                         && v.type.hasTag(NONE)) {
4668                     //self reference to implicitly typed variable declaration
4669                     log.error(TreeInfo.positionFor(v, env.enclClass), Errors.CantInferLocalVarType(v.name, Fragments.LocalSelfRef));
4670                     return v.type = types.createErrorType(v.type);
4671                 }
4672 
4673                 // Test (4): if symbol is an instance field of a raw type,
4674                 // which is being assigned to, issue an unchecked warning if
4675                 // its type changes under erasure.
4676                 if (KindSelector.ASG.subset(pkind()) &&
4677                     v.owner.kind == TYP &&
4678                     (v.flags() & STATIC) == 0 &&
4679                     (site.hasTag(CLASS) || site.hasTag(TYPEVAR))) {
4680                     Type s = types.asOuterSuper(site, v.owner);
4681                     if (s != null &&
4682                         s.isRaw() &&
4683                         !types.isSameType(v.type, v.erasure(types))) {
4684                         chk.warnUnchecked(tree.pos(), Warnings.UncheckedAssignToVar(v, s));
4685                     }
4686                 }
4687                 // The computed type of a variable is the type of the
4688                 // variable symbol, taken as a member of the site type.
4689                 owntype = (sym.owner.kind == TYP &&
4690                            sym.name != names._this && sym.name != names._super)
4691                     ? types.memberType(site, sym)
4692                     : sym.type;
4693 
4694                 // If the variable is a constant, record constant value in
4695                 // computed type.
4696                 if (v.getConstValue() != null && isStaticReference(tree))
4697                     owntype = owntype.constType(v.getConstValue());
4698 
4699                 if (resultInfo.pkind == KindSelector.VAL) {
4700                     owntype = capture(owntype); // capture "names as expressions"
4701                 }
4702                 break;
4703             case MTH: {
4704                 owntype = checkMethod(site, sym,
4705                         new ResultInfo(resultInfo.pkind, resultInfo.pt.getReturnType(), resultInfo.checkContext, resultInfo.checkMode),
4706                         env, TreeInfo.args(env.tree), resultInfo.pt.getParameterTypes(),
4707                         resultInfo.pt.getTypeArguments());
4708                 break;
4709             }
4710             case PCK: case ERR:
4711                 owntype = sym.type;
4712                 break;
4713             default:
4714                 throw new AssertionError("unexpected kind: " + sym.kind +
4715                                          " in tree " + tree);
4716             }
4717 
4718             // Emit a `deprecation' warning if symbol is deprecated.
4719             // (for constructors (but not for constructor references), the error
4720             // was given when the constructor was resolved)
4721 
4722             if (sym.name != names.init || tree.hasTag(REFERENCE)) {
4723                 chk.checkDeprecated(tree.pos(), env.info.scope.owner, sym);
4724                 chk.checkSunAPI(tree.pos(), sym);
4725                 chk.checkProfile(tree.pos(), sym);
4726                 chk.checkPreview(tree.pos(), env.info.scope.owner, sym);
4727             }
4728 
4729             // If symbol is a variable, check that its type and
4730             // kind are compatible with the prototype and protokind.
4731             return check(tree, owntype, sym.kind.toSelector(), resultInfo);
4732         }
4733 
4734         /** Check that variable is initialized and evaluate the variable's
4735          *  initializer, if not yet done. Also check that variable is not
4736          *  referenced before it is defined.
4737          *  @param tree    The tree making up the variable reference.
4738          *  @param env     The current environment.
4739          *  @param v       The variable's symbol.
4740          */
4741         private void checkInit(JCTree tree,
4742                                Env<AttrContext> env,
4743                                VarSymbol v,
4744                                boolean onlyWarning) {
4745             // A forward reference is diagnosed if the declaration position
4746             // of the variable is greater than the current tree position
4747             // and the tree and variable definition occur in the same class
4748             // definition.  Note that writes don't count as references.
4749             // This check applies only to class and instance
4750             // variables.  Local variables follow different scope rules,
4751             // and are subject to definite assignment checking.
4752             Env<AttrContext> initEnv = enclosingInitEnv(env);
4753             if (initEnv != null &&
4754                 (initEnv.info.enclVar == v || v.pos > tree.pos) &&
4755                 v.owner.kind == TYP &&
4756                 v.owner == env.info.scope.owner.enclClass() &&
4757                 ((v.flags() & STATIC) != 0) == Resolve.isStatic(env) &&
4758                 (!env.tree.hasTag(ASSIGN) ||
4759                  TreeInfo.skipParens(((JCAssign) env.tree).lhs) != tree)) {
4760                 if (!onlyWarning || isStaticEnumField(v)) {
4761                     Error errkey = (initEnv.info.enclVar == v) ?
4762                                 Errors.IllegalSelfRef : Errors.IllegalForwardRef;
4763                     log.error(tree.pos(), errkey);
4764                 } else if (useBeforeDeclarationWarning) {
4765                     Warning warnkey = (initEnv.info.enclVar == v) ?
4766                                 Warnings.SelfRef(v) : Warnings.ForwardRef(v);
4767                     log.warning(tree.pos(), warnkey);
4768                 }
4769             }
4770 
4771             v.getConstValue(); // ensure initializer is evaluated
4772 
4773             checkEnumInitializer(tree, env, v);
4774         }
4775 
4776         /**
4777          * Returns the enclosing init environment associated with this env (if any). An init env
4778          * can be either a field declaration env or a static/instance initializer env.
4779          */
4780         Env<AttrContext> enclosingInitEnv(Env<AttrContext> env) {
4781             while (true) {
4782                 switch (env.tree.getTag()) {
4783                     case VARDEF:
4784                         JCVariableDecl vdecl = (JCVariableDecl)env.tree;
4785                         if (vdecl.sym.owner.kind == TYP) {
4786                             //field
4787                             return env;
4788                         }
4789                         break;
4790                     case BLOCK:
4791                         if (env.next.tree.hasTag(CLASSDEF)) {
4792                             //instance/static initializer
4793                             return env;
4794                         }
4795                         break;
4796                     case METHODDEF:
4797                     case CLASSDEF:
4798                     case TOPLEVEL:
4799                         return null;
4800                 }
4801                 Assert.checkNonNull(env.next);
4802                 env = env.next;
4803             }
4804         }
4805 
4806         /**
4807          * Check for illegal references to static members of enum.  In
4808          * an enum type, constructors and initializers may not
4809          * reference its static members unless they are constant.
4810          *
4811          * @param tree    The tree making up the variable reference.
4812          * @param env     The current environment.
4813          * @param v       The variable's symbol.
4814          * @jls 8.9 Enum Types
4815          */
4816         private void checkEnumInitializer(JCTree tree, Env<AttrContext> env, VarSymbol v) {
4817             // JLS:
4818             //
4819             // "It is a compile-time error to reference a static field
4820             // of an enum type that is not a compile-time constant
4821             // (15.28) from constructors, instance initializer blocks,
4822             // or instance variable initializer expressions of that
4823             // type. It is a compile-time error for the constructors,
4824             // instance initializer blocks, or instance variable
4825             // initializer expressions of an enum constant e to refer
4826             // to itself or to an enum constant of the same type that
4827             // is declared to the right of e."
4828             if (isStaticEnumField(v)) {
4829                 ClassSymbol enclClass = env.info.scope.owner.enclClass();
4830 
4831                 if (enclClass == null || enclClass.owner == null)
4832                     return;
4833 
4834                 // See if the enclosing class is the enum (or a
4835                 // subclass thereof) declaring v.  If not, this
4836                 // reference is OK.
4837                 if (v.owner != enclClass && !types.isSubtype(enclClass.type, v.owner.type))
4838                     return;
4839 
4840                 // If the reference isn't from an initializer, then
4841                 // the reference is OK.
4842                 if (!Resolve.isInitializer(env))
4843                     return;
4844 
4845                 log.error(tree.pos(), Errors.IllegalEnumStaticRef);
4846             }
4847         }
4848 
4849         /** Is the given symbol a static, non-constant field of an Enum?
4850          *  Note: enum literals should not be regarded as such
4851          */
4852         private boolean isStaticEnumField(VarSymbol v) {
4853             return Flags.isEnum(v.owner) &&
4854                    Flags.isStatic(v) &&
4855                    !Flags.isConstant(v) &&
4856                    v.name != names._class;
4857         }
4858 
4859     /**
4860      * Check that method arguments conform to its instantiation.
4861      **/
4862     public Type checkMethod(Type site,
4863                             final Symbol sym,
4864                             ResultInfo resultInfo,
4865                             Env<AttrContext> env,
4866                             final List<JCExpression> argtrees,
4867                             List<Type> argtypes,
4868                             List<Type> typeargtypes) {
4869         // Test (5): if symbol is an instance method of a raw type, issue
4870         // an unchecked warning if its argument types change under erasure.
4871         if ((sym.flags() & STATIC) == 0 &&
4872             (site.hasTag(CLASS) || site.hasTag(TYPEVAR))) {
4873             Type s = types.asOuterSuper(site, sym.owner);
4874             if (s != null && s.isRaw() &&
4875                 !types.isSameTypes(sym.type.getParameterTypes(),
4876                                    sym.erasure(types).getParameterTypes())) {
4877                 chk.warnUnchecked(env.tree.pos(), Warnings.UncheckedCallMbrOfRawType(sym, s));
4878             }
4879         }
4880 
4881         if (env.info.defaultSuperCallSite != null) {
4882             for (Type sup : types.interfaces(env.enclClass.type).prepend(types.supertype((env.enclClass.type)))) {
4883                 if (!sup.tsym.isSubClass(sym.enclClass(), types) ||
4884                         types.isSameType(sup, env.info.defaultSuperCallSite)) continue;
4885                 List<MethodSymbol> icand_sup =
4886                         types.interfaceCandidates(sup, (MethodSymbol)sym);
4887                 if (icand_sup.nonEmpty() &&
4888                         icand_sup.head != sym &&
4889                         icand_sup.head.overrides(sym, icand_sup.head.enclClass(), types, true)) {
4890                     log.error(env.tree.pos(),
4891                               Errors.IllegalDefaultSuperCall(env.info.defaultSuperCallSite, Fragments.OverriddenDefault(sym, sup)));
4892                     break;
4893                 }
4894             }
4895             env.info.defaultSuperCallSite = null;
4896         }
4897 
4898         if (sym.isStatic() && site.isInterface() && env.tree.hasTag(APPLY)) {
4899             JCMethodInvocation app = (JCMethodInvocation)env.tree;
4900             if (app.meth.hasTag(SELECT) &&
4901                     !TreeInfo.isStaticSelector(((JCFieldAccess)app.meth).selected, names)) {
4902                 log.error(env.tree.pos(), Errors.IllegalStaticIntfMethCall(site));
4903             }
4904         }
4905 
4906         // Compute the identifier's instantiated type.
4907         // For methods, we need to compute the instance type by
4908         // Resolve.instantiate from the symbol's type as well as
4909         // any type arguments and value arguments.
4910         Warner noteWarner = new Warner();
4911         try {
4912             Type owntype = rs.checkMethod(
4913                     env,
4914                     site,
4915                     sym,
4916                     resultInfo,
4917                     argtypes,
4918                     typeargtypes,
4919                     noteWarner);
4920 
4921             DeferredAttr.DeferredTypeMap<Void> checkDeferredMap =
4922                 deferredAttr.new DeferredTypeMap<>(DeferredAttr.AttrMode.CHECK, sym, env.info.pendingResolutionPhase);
4923 
4924             argtypes = argtypes.map(checkDeferredMap);
4925 
4926             if (noteWarner.hasNonSilentLint(LintCategory.UNCHECKED)) {
4927                 chk.warnUnchecked(env.tree.pos(), Warnings.UncheckedMethInvocationApplied(kindName(sym),
4928                         sym.name,
4929                         rs.methodArguments(sym.type.getParameterTypes()),
4930                         rs.methodArguments(argtypes.map(checkDeferredMap)),
4931                         kindName(sym.location()),
4932                         sym.location()));
4933                 if (resultInfo.pt != Infer.anyPoly ||
4934                         !owntype.hasTag(METHOD) ||
4935                         !owntype.isPartial()) {
4936                     //if this is not a partially inferred method type, erase return type. Otherwise,
4937                     //erasure is carried out in PartiallyInferredMethodType.check().
4938                     owntype = new MethodType(owntype.getParameterTypes(),
4939                             types.erasure(owntype.getReturnType()),
4940                             types.erasure(owntype.getThrownTypes()),
4941                             syms.methodClass);
4942                 }
4943             }
4944 
4945             PolyKind pkind = (sym.type.hasTag(FORALL) &&
4946                  sym.type.getReturnType().containsAny(((ForAll)sym.type).tvars)) ?
4947                  PolyKind.POLY : PolyKind.STANDALONE;
4948             TreeInfo.setPolyKind(env.tree, pkind);
4949 
4950             return (resultInfo.pt == Infer.anyPoly) ?
4951                     owntype :
4952                     chk.checkMethod(owntype, sym, env, argtrees, argtypes, env.info.lastResolveVarargs(),
4953                             resultInfo.checkContext.inferenceContext());
4954         } catch (Infer.InferenceException ex) {
4955             //invalid target type - propagate exception outwards or report error
4956             //depending on the current check context
4957             resultInfo.checkContext.report(env.tree.pos(), ex.getDiagnostic());
4958             return types.createErrorType(site);
4959         } catch (Resolve.InapplicableMethodException ex) {
4960             final JCDiagnostic diag = ex.getDiagnostic();
4961             Resolve.InapplicableSymbolError errSym = rs.new InapplicableSymbolError(null) {
4962                 @Override
4963                 protected Pair<Symbol, JCDiagnostic> errCandidate() {
4964                     return new Pair<>(sym, diag);
4965                 }
4966             };
4967             List<Type> argtypes2 = argtypes.map(
4968                     rs.new ResolveDeferredRecoveryMap(AttrMode.CHECK, sym, env.info.pendingResolutionPhase));
4969             JCDiagnostic errDiag = errSym.getDiagnostic(JCDiagnostic.DiagnosticType.ERROR,
4970                     env.tree, sym, site, sym.name, argtypes2, typeargtypes);
4971             log.report(errDiag);
4972             return types.createErrorType(site);
4973         }
4974     }
4975 
4976     public void visitDefaultValue(JCDefaultValue tree) {
4977         if (!allowPrimitiveClasses) {
4978             log.error(DiagnosticFlag.SOURCE_LEVEL, tree.pos(),
4979                     Feature.PRIMITIVE_CLASSES.error(sourceName));
4980         }
4981 
4982         // Attribute the qualifier expression, and determine its symbol (if any).
4983         Type site = attribTree(tree.clazz, env, new ResultInfo(KindSelector.TYP_PCK, Type.noType));
4984         if (!pkind().contains(KindSelector.TYP_PCK))
4985             site = capture(site); // Capture field access
4986 
4987         Symbol sym = switch (site.getTag()) {
4988                 case WILDCARD -> throw new AssertionError(tree);
4989                 case PACKAGE -> {
4990                     log.error(tree.pos, Errors.CantResolveLocation(Kinds.KindName.CLASS, site.tsym.getQualifiedName(), null, null,
4991                             Fragments.Location(Kinds.typeKindName(env.enclClass.type), env.enclClass.type, null)));
4992                     yield syms.errSymbol;
4993                 }
4994                 case ERROR -> types.createErrorType(names._default, site.tsym, site).tsym;
4995                 default -> new VarSymbol(STATIC, names._default, site, site.tsym);
4996         };
4997 
4998         if (site.hasTag(TYPEVAR) && sym.kind != ERR) {
4999             site = types.skipTypeVars(site, true);
5000         }
5001         result = checkId(tree, site, sym, env, resultInfo);
5002     }
5003 
5004     public void visitLiteral(JCLiteral tree) {
5005         result = check(tree, litType(tree.typetag).constType(tree.value),
5006                 KindSelector.VAL, resultInfo);
5007     }
5008     //where
5009     /** Return the type of a literal with given type tag.
5010      */
5011     Type litType(TypeTag tag) {
5012         return (tag == CLASS) ? syms.stringType : syms.typeOfTag[tag.ordinal()];
5013     }
5014 
5015     public void visitTypeIdent(JCPrimitiveTypeTree tree) {
5016         result = check(tree, syms.typeOfTag[tree.typetag.ordinal()], KindSelector.TYP, resultInfo);
5017     }
5018 
5019     public void visitTypeArray(JCArrayTypeTree tree) {
5020         Type etype = attribType(tree.elemtype, env);
5021         Type type = new ArrayType(etype, syms.arrayClass);
5022         result = check(tree, type, KindSelector.TYP, resultInfo);
5023     }
5024 
5025     /** Visitor method for parameterized types.
5026      *  Bound checking is left until later, since types are attributed
5027      *  before supertype structure is completely known
5028      */
5029     public void visitTypeApply(JCTypeApply tree) {
5030         Type owntype = types.createErrorType(tree.type);
5031 
5032         // Attribute functor part of application and make sure it's a class.
5033         Type clazztype = chk.checkClassType(tree.clazz.pos(), attribType(tree.clazz, env));
5034 
5035         // Attribute type parameters
5036         List<Type> actuals = attribTypes(tree.arguments, env);
5037 
5038         if (clazztype.hasTag(CLASS)) {
5039             List<Type> formals = clazztype.tsym.type.getTypeArguments();
5040             if (actuals.isEmpty()) //diamond
5041                 actuals = formals;
5042 
5043             if (actuals.length() == formals.length()) {
5044                 List<Type> a = actuals;
5045                 List<Type> f = formals;
5046                 while (a.nonEmpty()) {
5047                     a.head = a.head.withTypeVar(f.head);
5048                     a = a.tail;
5049                     f = f.tail;
5050                 }
5051                 // Compute the proper generic outer
5052                 Type clazzOuter = clazztype.getEnclosingType();
5053                 if (clazzOuter.hasTag(CLASS)) {
5054                     Type site;
5055                     JCExpression clazz = TreeInfo.typeIn(tree.clazz);
5056                     if (clazz.hasTag(IDENT)) {
5057                         site = env.enclClass.sym.type;
5058                     } else if (clazz.hasTag(SELECT)) {
5059                         site = ((JCFieldAccess) clazz).selected.type;
5060                     } else throw new AssertionError(""+tree);
5061                     if (clazzOuter.hasTag(CLASS) && site != clazzOuter) {
5062                         if (site.hasTag(CLASS))
5063                             site = types.asOuterSuper(site, clazzOuter.tsym);
5064                         if (site == null)
5065                             site = types.erasure(clazzOuter);
5066                         clazzOuter = site;
5067                     }
5068                 }
5069                 owntype = new ClassType(clazzOuter, actuals, clazztype.tsym,
5070                                         clazztype.getMetadata(), clazztype.getFlavor());
5071             } else {
5072                 if (formals.length() != 0) {
5073                     log.error(tree.pos(),
5074                               Errors.WrongNumberTypeArgs(Integer.toString(formals.length())));
5075                 } else {
5076                     log.error(tree.pos(), Errors.TypeDoesntTakeParams(clazztype.tsym));
5077                 }
5078                 owntype = types.createErrorType(tree.type);
5079             }
5080         }
5081         result = check(tree, owntype, KindSelector.TYP, resultInfo);
5082     }
5083 
5084     public void visitTypeUnion(JCTypeUnion tree) {
5085         ListBuffer<Type> multicatchTypes = new ListBuffer<>();
5086         ListBuffer<Type> all_multicatchTypes = null; // lazy, only if needed
5087         for (JCExpression typeTree : tree.alternatives) {
5088             Type ctype = attribType(typeTree, env);
5089             ctype = chk.checkType(typeTree.pos(),
5090                           chk.checkClassType(typeTree.pos(), ctype),
5091                           syms.throwableType);
5092             if (!ctype.isErroneous()) {
5093                 //check that alternatives of a union type are pairwise
5094                 //unrelated w.r.t. subtyping
5095                 if (chk.intersects(ctype,  multicatchTypes.toList())) {
5096                     for (Type t : multicatchTypes) {
5097                         boolean sub = types.isSubtype(ctype, t);
5098                         boolean sup = types.isSubtype(t, ctype);
5099                         if (sub || sup) {
5100                             //assume 'a' <: 'b'
5101                             Type a = sub ? ctype : t;
5102                             Type b = sub ? t : ctype;
5103                             log.error(typeTree.pos(), Errors.MulticatchTypesMustBeDisjoint(a, b));
5104                         }
5105                     }
5106                 }
5107                 multicatchTypes.append(ctype);
5108                 if (all_multicatchTypes != null)
5109                     all_multicatchTypes.append(ctype);
5110             } else {
5111                 if (all_multicatchTypes == null) {
5112                     all_multicatchTypes = new ListBuffer<>();
5113                     all_multicatchTypes.appendList(multicatchTypes);
5114                 }
5115                 all_multicatchTypes.append(ctype);
5116             }
5117         }
5118         Type t = check(tree, types.lub(multicatchTypes.toList()),
5119                 KindSelector.TYP, resultInfo.dup(CheckMode.NO_TREE_UPDATE));
5120         if (t.hasTag(CLASS)) {
5121             List<Type> alternatives =
5122                 ((all_multicatchTypes == null) ? multicatchTypes : all_multicatchTypes).toList();
5123             t = new UnionClassType((ClassType) t, alternatives);
5124         }
5125         tree.type = result = t;
5126     }
5127 
5128     public void visitTypeIntersection(JCTypeIntersection tree) {
5129         attribTypes(tree.bounds, env);
5130         tree.type = result = checkIntersection(tree, tree.bounds);
5131     }
5132 
5133     public void visitTypeParameter(JCTypeParameter tree) {
5134         TypeVar typeVar = (TypeVar) tree.type;
5135 
5136         if (tree.annotations != null && tree.annotations.nonEmpty()) {
5137             annotate.annotateTypeParameterSecondStage(tree, tree.annotations);
5138         }
5139 
5140         if (!typeVar.getUpperBound().isErroneous()) {
5141             //fixup type-parameter bound computed in 'attribTypeVariables'
5142             typeVar.setUpperBound(checkIntersection(tree, tree.bounds));
5143         }
5144     }
5145 
5146     Type checkIntersection(JCTree tree, List<JCExpression> bounds) {
5147         Set<Type> boundSet = new HashSet<>();
5148         if (bounds.nonEmpty()) {
5149             // accept class or interface or typevar as first bound.
5150             bounds.head.type = checkBase(bounds.head.type, bounds.head, env, false, false, false);
5151             boundSet.add(types.erasure(bounds.head.type));
5152             if (bounds.head.type.isErroneous()) {
5153                 return bounds.head.type;
5154             }
5155             else if (bounds.head.type.hasTag(TYPEVAR)) {
5156                 // if first bound was a typevar, do not accept further bounds.
5157                 if (bounds.tail.nonEmpty()) {
5158                     log.error(bounds.tail.head.pos(),
5159                               Errors.TypeVarMayNotBeFollowedByOtherBounds);
5160                     return bounds.head.type;
5161                 }
5162             } else {
5163                 // if first bound was a class or interface, accept only interfaces
5164                 // as further bounds.
5165                 for (JCExpression bound : bounds.tail) {
5166                     bound.type = checkBase(bound.type, bound, env, false, true, false);
5167                     if (bound.type.isErroneous()) {
5168                         bounds = List.of(bound);
5169                     }
5170                     else if (bound.type.hasTag(CLASS)) {
5171                         chk.checkNotRepeated(bound.pos(), types.erasure(bound.type), boundSet);
5172                     }
5173                 }
5174             }
5175         }
5176 
5177         if (bounds.length() == 0) {
5178             return syms.objectType;
5179         } else if (bounds.length() == 1) {
5180             return bounds.head.type;
5181         } else {
5182             Type owntype = types.makeIntersectionType(TreeInfo.types(bounds));
5183             // ... the variable's bound is a class type flagged COMPOUND
5184             // (see comment for TypeVar.bound).
5185             // In this case, generate a class tree that represents the
5186             // bound class, ...
5187             JCExpression extending;
5188             List<JCExpression> implementing;
5189             if (!bounds.head.type.isInterface()) {
5190                 extending = bounds.head;
5191                 implementing = bounds.tail;
5192             } else {
5193                 extending = null;
5194                 implementing = bounds;
5195             }
5196             JCClassDecl cd = make.at(tree).ClassDef(
5197                 make.Modifiers(PUBLIC | ABSTRACT | (extending != null && TreeInfo.symbol(extending).isPrimitiveClass() ? PRIMITIVE_CLASS : 0)),
5198                 names.empty, List.nil(),
5199                 extending, implementing, List.nil());
5200 
5201             ClassSymbol c = (ClassSymbol)owntype.tsym;
5202             Assert.check((c.flags() & COMPOUND) != 0);
5203             cd.sym = c;
5204             c.sourcefile = env.toplevel.sourcefile;
5205 
5206             // ... and attribute the bound class
5207             c.flags_field |= UNATTRIBUTED;
5208             Env<AttrContext> cenv = enter.classEnv(cd, env);
5209             typeEnvs.put(c, cenv);
5210             attribClass(c);
5211             return owntype;
5212         }
5213     }
5214 
5215     public void visitWildcard(JCWildcard tree) {
5216         //- System.err.println("visitWildcard("+tree+");");//DEBUG
5217         Type type = (tree.kind.kind == BoundKind.UNBOUND)
5218             ? syms.objectType
5219             : attribType(tree.inner, env);
5220         result = check(tree, new WildcardType(chk.checkRefType(tree.pos(), type, false),
5221                                               tree.kind.kind,
5222                                               syms.boundClass),
5223                 KindSelector.TYP, resultInfo);
5224     }
5225 
5226     public void visitAnnotation(JCAnnotation tree) {
5227         Assert.error("should be handled in annotate");
5228     }
5229 
5230     @Override
5231     public void visitModifiers(JCModifiers tree) {
5232         //error recovery only:
5233         Assert.check(resultInfo.pkind == KindSelector.ERR);
5234 
5235         attribAnnotationTypes(tree.annotations, env);
5236     }
5237 
5238     public void visitAnnotatedType(JCAnnotatedType tree) {
5239         attribAnnotationTypes(tree.annotations, env);
5240         Type underlyingType = attribType(tree.underlyingType, env);
5241         Type annotatedType = underlyingType.annotatedType(Annotations.TO_BE_SET);
5242 
5243         if (!env.info.isNewClass)
5244             annotate.annotateTypeSecondStage(tree, tree.annotations, annotatedType);
5245         result = tree.type = annotatedType;
5246     }
5247 
5248     public void visitErroneous(JCErroneous tree) {
5249         if (tree.errs != null) {
5250             Env<AttrContext> errEnv = env.dup(env.tree);
5251             errEnv.info.returnResult = unknownExprInfo;
5252             for (JCTree err : tree.errs)
5253                 attribTree(err, errEnv, new ResultInfo(KindSelector.ERR, pt()));
5254         }
5255         result = tree.type = syms.errType;
5256     }
5257 
5258     /** Default visitor method for all other trees.
5259      */
5260     public void visitTree(JCTree tree) {
5261         throw new AssertionError();
5262     }
5263 
5264     /**
5265      * Attribute an env for either a top level tree or class or module declaration.
5266      */
5267     public void attrib(Env<AttrContext> env) {
5268         switch (env.tree.getTag()) {
5269             case MODULEDEF:
5270                 attribModule(env.tree.pos(), ((JCModuleDecl)env.tree).sym);
5271                 break;
5272             case TOPLEVEL:
5273                 attribTopLevel(env);
5274                 break;
5275             case PACKAGEDEF:
5276                 attribPackage(env.tree.pos(), ((JCPackageDecl) env.tree).packge);
5277                 break;
5278             default:
5279                 attribClass(env.tree.pos(), env.enclClass.sym);
5280         }
5281     }
5282 
5283     /**
5284      * Attribute a top level tree. These trees are encountered when the
5285      * package declaration has annotations.
5286      */
5287     public void attribTopLevel(Env<AttrContext> env) {
5288         JCCompilationUnit toplevel = env.toplevel;
5289         try {
5290             annotate.flush();
5291         } catch (CompletionFailure ex) {
5292             chk.completionError(toplevel.pos(), ex);
5293         }
5294     }
5295 
5296     public void attribPackage(DiagnosticPosition pos, PackageSymbol p) {
5297         try {
5298             annotate.flush();
5299             attribPackage(p);
5300         } catch (CompletionFailure ex) {
5301             chk.completionError(pos, ex);
5302         }
5303     }
5304 
5305     void attribPackage(PackageSymbol p) {
5306         attribWithLint(p,
5307                        env -> chk.checkDeprecatedAnnotation(((JCPackageDecl) env.tree).pid.pos(), p));
5308     }
5309 
5310     public void attribModule(DiagnosticPosition pos, ModuleSymbol m) {
5311         try {
5312             annotate.flush();
5313             attribModule(m);
5314         } catch (CompletionFailure ex) {
5315             chk.completionError(pos, ex);
5316         }
5317     }
5318 
5319     void attribModule(ModuleSymbol m) {
5320         attribWithLint(m, env -> attribStat(env.tree, env));
5321     }
5322 
5323     private void attribWithLint(TypeSymbol sym, Consumer<Env<AttrContext>> attrib) {
5324         Env<AttrContext> env = typeEnvs.get(sym);
5325 
5326         Env<AttrContext> lintEnv = env;
5327         while (lintEnv.info.lint == null)
5328             lintEnv = lintEnv.next;
5329 
5330         Lint lint = lintEnv.info.lint.augment(sym);
5331 
5332         Lint prevLint = chk.setLint(lint);
5333         JavaFileObject prev = log.useSource(env.toplevel.sourcefile);
5334 
5335         try {
5336             deferredLintHandler.flush(env.tree.pos());
5337             attrib.accept(env);
5338         } finally {
5339             log.useSource(prev);
5340             chk.setLint(prevLint);
5341         }
5342     }
5343 
5344     /** Main method: attribute class definition associated with given class symbol.
5345      *  reporting completion failures at the given position.
5346      *  @param pos The source position at which completion errors are to be
5347      *             reported.
5348      *  @param c   The class symbol whose definition will be attributed.
5349      */
5350     public void attribClass(DiagnosticPosition pos, ClassSymbol c) {
5351         try {
5352             annotate.flush();
5353             attribClass(c);
5354             if (c.type.isPrimitiveClass()) {
5355                 final Env<AttrContext> env = typeEnvs.get(c);
5356                 if (env != null && env.tree != null && env.tree.hasTag(CLASSDEF))
5357                     chk.checkNonCyclicMembership((JCClassDecl)env.tree);
5358             }
5359         } catch (CompletionFailure ex) {
5360             chk.completionError(pos, ex);
5361         }
5362     }
5363 
5364     /** Attribute class definition associated with given class symbol.
5365      *  @param c   The class symbol whose definition will be attributed.
5366      */
5367     void attribClass(ClassSymbol c) throws CompletionFailure {
5368         if (c.type.hasTag(ERROR)) return;
5369 
5370         // Check for cycles in the inheritance graph, which can arise from
5371         // ill-formed class files.
5372         chk.checkNonCyclic(null, c.type);
5373 
5374         Type st = types.supertype(c.type);
5375         if ((c.flags_field & Flags.COMPOUND) == 0 &&
5376             (c.flags_field & Flags.SUPER_OWNER_ATTRIBUTED) == 0) {
5377             // First, attribute superclass.
5378             if (st.hasTag(CLASS))
5379                 attribClass((ClassSymbol)st.tsym);
5380 
5381             // Next attribute owner, if it is a class.
5382             if (c.owner.kind == TYP && c.owner.type.hasTag(CLASS))
5383                 attribClass((ClassSymbol)c.owner);
5384 
5385             c.flags_field |= Flags.SUPER_OWNER_ATTRIBUTED;
5386         }
5387 
5388         // The previous operations might have attributed the current class
5389         // if there was a cycle. So we test first whether the class is still
5390         // UNATTRIBUTED.
5391         if ((c.flags_field & UNATTRIBUTED) != 0) {
5392             c.flags_field &= ~UNATTRIBUTED;
5393 
5394             // Get environment current at the point of class definition.
5395             Env<AttrContext> env = typeEnvs.get(c);
5396 
5397             if (c.isSealed() &&
5398                     !c.isEnum() &&
5399                     !c.isPermittedExplicit &&
5400                     c.permitted.isEmpty()) {
5401                 log.error(TreeInfo.diagnosticPositionFor(c, env.tree), Errors.SealedClassMustHaveSubclasses);
5402             }
5403 
5404             if (c.isSealed()) {
5405                 Set<Symbol> permittedTypes = new HashSet<>();
5406                 boolean sealedInUnnamed = c.packge().modle == syms.unnamedModule || c.packge().modle == syms.noModule;
5407                 for (Symbol subTypeSym : c.permitted) {
5408                     boolean isTypeVar = false;
5409                     if (subTypeSym.type.getTag() == TYPEVAR) {
5410                         isTypeVar = true; //error recovery
5411                         log.error(TreeInfo.diagnosticPositionFor(subTypeSym, env.tree),
5412                                 Errors.InvalidPermitsClause(Fragments.IsATypeVariable(subTypeSym.type)));
5413                     }
5414                     if (subTypeSym.isAnonymous() && !c.isEnum()) {
5415                         log.error(TreeInfo.diagnosticPositionFor(subTypeSym, env.tree),  Errors.LocalClassesCantExtendSealed(Fragments.Anonymous));
5416                     }
5417                     if (permittedTypes.contains(subTypeSym)) {
5418                         DiagnosticPosition pos =
5419                                 env.enclClass.permitting.stream()
5420                                         .filter(permittedExpr -> TreeInfo.diagnosticPositionFor(subTypeSym, permittedExpr, true) != null)
5421                                         .limit(2).collect(List.collector()).get(1);
5422                         log.error(pos, Errors.InvalidPermitsClause(Fragments.IsDuplicated(subTypeSym.type)));
5423                     } else {
5424                         permittedTypes.add(subTypeSym);
5425                     }
5426                     if (sealedInUnnamed) {
5427                         if (subTypeSym.packge() != c.packge()) {
5428                             log.error(TreeInfo.diagnosticPositionFor(subTypeSym, env.tree),
5429                                     Errors.ClassInUnnamedModuleCantExtendSealedInDiffPackage(c)
5430                             );
5431                         }
5432                     } else if (subTypeSym.packge().modle != c.packge().modle) {
5433                         log.error(TreeInfo.diagnosticPositionFor(subTypeSym, env.tree),
5434                                 Errors.ClassInModuleCantExtendSealedInDiffModule(c, c.packge().modle)
5435                         );
5436                     }
5437                     if (subTypeSym == c.type.tsym || types.isSuperType(subTypeSym.type, c.type)) {
5438                         log.error(TreeInfo.diagnosticPositionFor(subTypeSym, ((JCClassDecl)env.tree).permitting),
5439                                 Errors.InvalidPermitsClause(
5440                                         subTypeSym == c.type.tsym ?
5441                                                 Fragments.MustNotBeSameClass :
5442                                                 Fragments.MustNotBeSupertype(subTypeSym.type)
5443                                 )
5444                         );
5445                     } else if (!isTypeVar) {
5446                         boolean thisIsASuper = types.directSupertypes(subTypeSym.type)
5447                                                     .stream()
5448                                                     .anyMatch(d -> d.tsym == c);
5449                         if (!thisIsASuper) {
5450                             log.error(TreeInfo.diagnosticPositionFor(subTypeSym, env.tree),
5451                                     Errors.InvalidPermitsClause(Fragments.DoesntExtendSealed(subTypeSym.type)));
5452                         }
5453                     }
5454                 }
5455             }
5456 
5457             List<ClassSymbol> sealedSupers = types.directSupertypes(c.type)
5458                                                   .stream()
5459                                                   .filter(s -> s.tsym.isSealed())
5460                                                   .map(s -> (ClassSymbol) s.tsym)
5461                                                   .collect(List.collector());
5462 
5463             if (sealedSupers.isEmpty()) {
5464                 if ((c.flags_field & Flags.NON_SEALED) != 0) {
5465                     boolean hasErrorSuper = false;
5466 
5467                     hasErrorSuper |= types.directSupertypes(c.type)
5468                                           .stream()
5469                                           .anyMatch(s -> s.tsym.kind == Kind.ERR);
5470 
5471                     ClassType ct = (ClassType) c.type;
5472 
5473                     hasErrorSuper |= !ct.isCompound() && ct.interfaces_field != ct.all_interfaces_field;
5474 
5475                     if (!hasErrorSuper) {
5476                         log.error(TreeInfo.diagnosticPositionFor(c, env.tree), Errors.NonSealedWithNoSealedSupertype(c));
5477                     }
5478                 }
5479             } else if ((c.flags_field & Flags.COMPOUND) == 0) {
5480                 if (c.isDirectlyOrIndirectlyLocal() && !c.isEnum()) {
5481                     log.error(TreeInfo.diagnosticPositionFor(c, env.tree), Errors.LocalClassesCantExtendSealed(c.isAnonymous() ? Fragments.Anonymous : Fragments.Local));
5482                 }
5483 
5484                 if (!c.type.isCompound()) {
5485                     for (ClassSymbol supertypeSym : sealedSupers) {
5486                         if (!supertypeSym.permitted.contains(c.type.tsym)) {
5487                             log.error(TreeInfo.diagnosticPositionFor(c.type.tsym, env.tree), Errors.CantInheritFromSealed(supertypeSym));
5488                         }
5489                     }
5490                     if (!c.isNonSealed() && !c.isFinal() && !c.isSealed()) {
5491                         log.error(TreeInfo.diagnosticPositionFor(c, env.tree),
5492                                 c.isInterface() ?
5493                                         Errors.NonSealedOrSealedExpected :
5494                                         Errors.NonSealedSealedOrFinalExpected);
5495                     }
5496                 }
5497             }
5498 
5499             // The info.lint field in the envs stored in typeEnvs is deliberately uninitialized,
5500             // because the annotations were not available at the time the env was created. Therefore,
5501             // we look up the environment chain for the first enclosing environment for which the
5502             // lint value is set. Typically, this is the parent env, but might be further if there
5503             // are any envs created as a result of TypeParameter nodes.
5504             Env<AttrContext> lintEnv = env;
5505             while (lintEnv.info.lint == null)
5506                 lintEnv = lintEnv.next;
5507 
5508             // Having found the enclosing lint value, we can initialize the lint value for this class
5509             env.info.lint = lintEnv.info.lint.augment(c);
5510 
5511             Lint prevLint = chk.setLint(env.info.lint);
5512             JavaFileObject prev = log.useSource(c.sourcefile);
5513             ResultInfo prevReturnRes = env.info.returnResult;
5514 
5515             try {
5516                 deferredLintHandler.flush(env.tree);
5517                 env.info.returnResult = null;
5518                 // java.lang.Enum may not be subclassed by a non-enum
5519                 if (st.tsym == syms.enumSym &&
5520                     ((c.flags_field & (Flags.ENUM|Flags.COMPOUND)) == 0))
5521                     log.error(env.tree.pos(), Errors.EnumNoSubclassing);
5522 
5523                 // Enums may not be extended by source-level classes
5524                 if (st.tsym != null &&
5525                     ((st.tsym.flags_field & Flags.ENUM) != 0) &&
5526                     ((c.flags_field & (Flags.ENUM | Flags.COMPOUND)) == 0)) {
5527                     log.error(env.tree.pos(), Errors.EnumTypesNotExtensible);
5528                 }
5529 
5530                 if (rs.isSerializable(c.type)) {
5531                     env.info.isSerializable = true;
5532                 }
5533 
5534                 if ((c.flags() & (VALUE_CLASS | ABSTRACT)) == VALUE_CLASS) { // for non-intersection, concrete primitive/value classes.
5535                     Assert.check(env.tree.hasTag(CLASSDEF));
5536                     JCClassDecl classDecl = (JCClassDecl) env.tree;
5537                     if (classDecl.extending != null) {
5538                         chk.checkSuperConstraintsOfValueClass(env.tree.pos(), c);
5539                     }
5540                 }
5541 
5542                 attribClassBody(env, c);
5543 
5544                 chk.checkDeprecatedAnnotation(env.tree.pos(), c);
5545                 chk.checkClassOverrideEqualsAndHashIfNeeded(env.tree.pos(), c);
5546                 chk.checkFunctionalInterface((JCClassDecl) env.tree, c);
5547                 chk.checkLeaksNotAccessible(env, (JCClassDecl) env.tree);
5548             } finally {
5549                 env.info.returnResult = prevReturnRes;
5550                 log.useSource(prev);
5551                 chk.setLint(prevLint);
5552             }
5553 
5554         }
5555     }
5556 
5557     public void visitImport(JCImport tree) {
5558         // nothing to do
5559     }
5560 
5561     public void visitModuleDef(JCModuleDecl tree) {
5562         tree.sym.completeUsesProvides();
5563         ModuleSymbol msym = tree.sym;
5564         Lint lint = env.outer.info.lint = env.outer.info.lint.augment(msym);
5565         Lint prevLint = chk.setLint(lint);
5566         chk.checkModuleName(tree);
5567         chk.checkDeprecatedAnnotation(tree, msym);
5568 
5569         try {
5570             deferredLintHandler.flush(tree.pos());
5571         } finally {
5572             chk.setLint(prevLint);
5573         }
5574     }
5575 
5576     /** Finish the attribution of a class. */
5577     private void attribClassBody(Env<AttrContext> env, ClassSymbol c) {
5578         JCClassDecl tree = (JCClassDecl)env.tree;
5579         Assert.check(c == tree.sym);
5580 
5581         // Validate type parameters, supertype and interfaces.
5582         attribStats(tree.typarams, env);
5583         if (!c.isAnonymous()) {
5584             //already checked if anonymous
5585             chk.validate(tree.typarams, env);
5586             chk.validate(tree.extending, env);
5587             chk.validate(tree.implementing, env);
5588         }
5589 
5590         c.markAbstractIfNeeded(types);
5591 
5592         // If this is a non-abstract class, check that it has no abstract
5593         // methods or unimplemented methods of an implemented interface.
5594         if ((c.flags() & (ABSTRACT | INTERFACE)) == 0) {
5595             chk.checkAllDefined(tree.pos(), c);
5596         }
5597 
5598         if ((c.flags() & ANNOTATION) != 0) {
5599             if (tree.implementing.nonEmpty())
5600                 log.error(tree.implementing.head.pos(),
5601                           Errors.CantExtendIntfAnnotation);
5602             if (tree.typarams.nonEmpty()) {
5603                 log.error(tree.typarams.head.pos(),
5604                           Errors.IntfAnnotationCantHaveTypeParams(c));
5605             }
5606 
5607             // If this annotation type has a @Repeatable, validate
5608             Attribute.Compound repeatable = c.getAnnotationTypeMetadata().getRepeatable();
5609             // If this annotation type has a @Repeatable, validate
5610             if (repeatable != null) {
5611                 // get diagnostic position for error reporting
5612                 DiagnosticPosition cbPos = getDiagnosticPosition(tree, repeatable.type);
5613                 Assert.checkNonNull(cbPos);
5614 
5615                 chk.validateRepeatable(c, repeatable, cbPos);
5616             }
5617         } else {
5618             // Check that all extended classes and interfaces
5619             // are compatible (i.e. no two define methods with same arguments
5620             // yet different return types).  (JLS 8.4.8.3)
5621             chk.checkCompatibleSupertypes(tree.pos(), c.type);
5622             if (allowDefaultMethods) {
5623                 chk.checkDefaultMethodClashes(tree.pos(), c.type);
5624             }
5625         }
5626 
5627         // Check that class does not import the same parameterized interface
5628         // with two different argument lists.
5629         chk.checkClassBounds(tree.pos(), c.type);
5630 
5631         tree.type = c.type;
5632 
5633         for (List<JCTypeParameter> l = tree.typarams;
5634              l.nonEmpty(); l = l.tail) {
5635              Assert.checkNonNull(env.info.scope.findFirst(l.head.name));
5636         }
5637 
5638         // Check that a generic class doesn't extend Throwable
5639         if (!c.type.allparams().isEmpty() && types.isSubtype(c.type, syms.throwableType))
5640             log.error(tree.extending.pos(), Errors.GenericThrowable);
5641 
5642         // Check that all methods which implement some
5643         // method conform to the method they implement.
5644         chk.checkImplementations(tree);
5645 
5646         //check that a resource implementing AutoCloseable cannot throw InterruptedException
5647         checkAutoCloseable(tree.pos(), env, c.type);
5648 
5649         for (List<JCTree> l = tree.defs; l.nonEmpty(); l = l.tail) {
5650             // Attribute declaration
5651             attribStat(l.head, env);
5652             // Check that declarations in inner classes are not static (JLS 8.1.2)
5653             // Make an exception for static constants.
5654             if (!allowRecords &&
5655                     c.owner.kind != PCK &&
5656                     ((c.flags() & STATIC) == 0 || c.name == names.empty) &&
5657                     (TreeInfo.flags(l.head) & (STATIC | INTERFACE)) != 0) {
5658                 VarSymbol sym = null;
5659                 if (l.head.hasTag(VARDEF)) sym = ((JCVariableDecl) l.head).sym;
5660                 if (sym == null ||
5661                         sym.kind != VAR ||
5662                         sym.getConstValue() == null)
5663                     log.error(l.head.pos(), Errors.IclsCantHaveStaticDecl(c));
5664             }
5665         }
5666 
5667         // Check for cycles among non-initial constructors.
5668         chk.checkCyclicConstructors(tree);
5669 
5670         // Check for cycles among annotation elements.
5671         chk.checkNonCyclicElements(tree);
5672 
5673         // Check for proper use of serialVersionUID and other
5674         // serialization-related fields and methods
5675         if (env.info.lint.isEnabled(LintCategory.SERIAL)
5676                 && rs.isSerializable(c.type)
5677                 && !c.isAnonymous()) {
5678             chk.checkSerialStructure(tree, c);
5679         }
5680         if (allowTypeAnnos) {
5681             // Correctly organize the positions of the type annotations
5682             typeAnnotations.organizeTypeAnnotationsBodies(tree);
5683 
5684             // Check type annotations applicability rules
5685             validateTypeAnnotations(tree, false);
5686         }
5687     }
5688         // where
5689         /** get a diagnostic position for an attribute of Type t, or null if attribute missing */
5690         private DiagnosticPosition getDiagnosticPosition(JCClassDecl tree, Type t) {
5691             for(List<JCAnnotation> al = tree.mods.annotations; !al.isEmpty(); al = al.tail) {
5692                 if (types.isSameType(al.head.annotationType.type, t))
5693                     return al.head.pos();
5694             }
5695 
5696             return null;
5697         }
5698 
5699     private Type capture(Type type) {
5700         return types.capture(type);
5701     }
5702 
5703     private void setSyntheticVariableType(JCVariableDecl tree, Type type) {
5704         if (type.isErroneous()) {
5705             tree.vartype = make.at(Position.NOPOS).Erroneous();
5706         } else {
5707             tree.vartype = make.at(Position.NOPOS).Type(type);
5708         }
5709     }
5710 
5711     public void validateTypeAnnotations(JCTree tree, boolean sigOnly) {
5712         tree.accept(new TypeAnnotationsValidator(sigOnly));
5713     }
5714     //where
5715     private final class TypeAnnotationsValidator extends TreeScanner {
5716 
5717         private final boolean sigOnly;
5718         public TypeAnnotationsValidator(boolean sigOnly) {
5719             this.sigOnly = sigOnly;
5720         }
5721 
5722         public void visitAnnotation(JCAnnotation tree) {
5723             chk.validateTypeAnnotation(tree, false);
5724             super.visitAnnotation(tree);
5725         }
5726         public void visitAnnotatedType(JCAnnotatedType tree) {
5727             if (!tree.underlyingType.type.isErroneous()) {
5728                 super.visitAnnotatedType(tree);
5729             }
5730         }
5731         public void visitTypeParameter(JCTypeParameter tree) {
5732             chk.validateTypeAnnotations(tree.annotations, true);
5733             scan(tree.bounds);
5734             // Don't call super.
5735             // This is needed because above we call validateTypeAnnotation with
5736             // false, which would forbid annotations on type parameters.
5737             // super.visitTypeParameter(tree);
5738         }
5739         public void visitMethodDef(JCMethodDecl tree) {
5740             if (tree.recvparam != null &&
5741                     !tree.recvparam.vartype.type.isErroneous()) {
5742                 checkForDeclarationAnnotations(tree.recvparam.mods.annotations, tree.recvparam.sym);
5743             }
5744             if (tree.restype != null && tree.restype.type != null) {
5745                 validateAnnotatedType(tree.restype, tree.restype.type);
5746             }
5747             if (sigOnly) {
5748                 scan(tree.mods);
5749                 scan(tree.restype);
5750                 scan(tree.typarams);
5751                 scan(tree.recvparam);
5752                 scan(tree.params);
5753                 scan(tree.thrown);
5754             } else {
5755                 scan(tree.defaultValue);
5756                 scan(tree.body);
5757             }
5758         }
5759         public void visitVarDef(final JCVariableDecl tree) {
5760             //System.err.println("validateTypeAnnotations.visitVarDef " + tree);
5761             if (tree.sym != null && tree.sym.type != null && !tree.isImplicitlyTyped())
5762                 validateAnnotatedType(tree.vartype, tree.sym.type);
5763             scan(tree.mods);
5764             scan(tree.vartype);
5765             if (!sigOnly) {
5766                 scan(tree.init);
5767             }
5768         }
5769         public void visitTypeCast(JCTypeCast tree) {
5770             if (tree.clazz != null && tree.clazz.type != null)
5771                 validateAnnotatedType(tree.clazz, tree.clazz.type);
5772             super.visitTypeCast(tree);
5773         }
5774         public void visitTypeTest(JCInstanceOf tree) {
5775             if (tree.pattern != null && !(tree.pattern instanceof JCPattern) && tree.pattern.type != null)
5776                 validateAnnotatedType(tree.pattern, tree.pattern.type);
5777             super.visitTypeTest(tree);
5778         }
5779         public void visitNewClass(JCNewClass tree) {
5780             if (tree.clazz != null && tree.clazz.type != null) {
5781                 if (tree.clazz.hasTag(ANNOTATED_TYPE)) {
5782                     checkForDeclarationAnnotations(((JCAnnotatedType) tree.clazz).annotations,
5783                             tree.clazz.type.tsym);
5784                 }
5785                 if (tree.def != null) {
5786                     checkForDeclarationAnnotations(tree.def.mods.annotations, tree.clazz.type.tsym);
5787                 }
5788 
5789                 validateAnnotatedType(tree.clazz, tree.clazz.type);
5790             }
5791             super.visitNewClass(tree);
5792         }
5793         public void visitNewArray(JCNewArray tree) {
5794             if (tree.elemtype != null && tree.elemtype.type != null) {
5795                 if (tree.elemtype.hasTag(ANNOTATED_TYPE)) {
5796                     checkForDeclarationAnnotations(((JCAnnotatedType) tree.elemtype).annotations,
5797                             tree.elemtype.type.tsym);
5798                 }
5799                 validateAnnotatedType(tree.elemtype, tree.elemtype.type);
5800             }
5801             super.visitNewArray(tree);
5802         }
5803         public void visitClassDef(JCClassDecl tree) {
5804             //System.err.println("validateTypeAnnotations.visitClassDef " + tree);
5805             if (sigOnly) {
5806                 scan(tree.mods);
5807                 scan(tree.typarams);
5808                 scan(tree.extending);
5809                 scan(tree.implementing);
5810             }
5811             for (JCTree member : tree.defs) {
5812                 if (member.hasTag(Tag.CLASSDEF)) {
5813                     continue;
5814                 }
5815                 scan(member);
5816             }
5817         }
5818         public void visitBlock(JCBlock tree) {
5819             if (!sigOnly) {
5820                 scan(tree.stats);
5821             }
5822         }
5823 
5824         /* I would want to model this after
5825          * com.sun.tools.javac.comp.Check.Validator.visitSelectInternal(JCFieldAccess)
5826          * and override visitSelect and visitTypeApply.
5827          * However, we only set the annotated type in the top-level type
5828          * of the symbol.
5829          * Therefore, we need to override each individual location where a type
5830          * can occur.
5831          */
5832         private void validateAnnotatedType(final JCTree errtree, final Type type) {
5833             //System.err.println("Attr.validateAnnotatedType: " + errtree + " type: " + type);
5834 
5835             if (type.isPrimitiveOrVoid()) {
5836                 return;
5837             }
5838 
5839             JCTree enclTr = errtree;
5840             Type enclTy = type;
5841 
5842             boolean repeat = true;
5843             while (repeat) {
5844                 if (enclTr.hasTag(TYPEAPPLY)) {
5845                     List<Type> tyargs = enclTy.getTypeArguments();
5846                     List<JCExpression> trargs = ((JCTypeApply)enclTr).getTypeArguments();
5847                     if (trargs.length() > 0) {
5848                         // Nothing to do for diamonds
5849                         if (tyargs.length() == trargs.length()) {
5850                             for (int i = 0; i < tyargs.length(); ++i) {
5851                                 validateAnnotatedType(trargs.get(i), tyargs.get(i));
5852                             }
5853                         }
5854                         // If the lengths don't match, it's either a diamond
5855                         // or some nested type that redundantly provides
5856                         // type arguments in the tree.
5857                     }
5858 
5859                     // Look at the clazz part of a generic type
5860                     enclTr = ((JCTree.JCTypeApply)enclTr).clazz;
5861                 }
5862 
5863                 if (enclTr.hasTag(SELECT)) {
5864                     enclTr = ((JCTree.JCFieldAccess)enclTr).getExpression();
5865                     if (enclTy != null &&
5866                             !enclTy.hasTag(NONE)) {
5867                         enclTy = enclTy.getEnclosingType();
5868                     }
5869                 } else if (enclTr.hasTag(ANNOTATED_TYPE)) {
5870                     JCAnnotatedType at = (JCTree.JCAnnotatedType) enclTr;
5871                     if (enclTy == null || enclTy.hasTag(NONE)) {
5872                         if (at.getAnnotations().size() == 1) {
5873                             log.error(at.underlyingType.pos(), Errors.CantTypeAnnotateScoping1(at.getAnnotations().head.attribute));
5874                         } else {
5875                             ListBuffer<Attribute.Compound> comps = new ListBuffer<>();
5876                             for (JCAnnotation an : at.getAnnotations()) {
5877                                 comps.add(an.attribute);
5878                             }
5879                             log.error(at.underlyingType.pos(), Errors.CantTypeAnnotateScoping(comps.toList()));
5880                         }
5881                         repeat = false;
5882                     }
5883                     enclTr = at.underlyingType;
5884                     // enclTy doesn't need to be changed
5885                 } else if (enclTr.hasTag(IDENT)) {
5886                     repeat = false;
5887                 } else if (enclTr.hasTag(JCTree.Tag.WILDCARD)) {
5888                     JCWildcard wc = (JCWildcard) enclTr;
5889                     if (wc.getKind() == JCTree.Kind.EXTENDS_WILDCARD ||
5890                             wc.getKind() == JCTree.Kind.SUPER_WILDCARD) {
5891                         validateAnnotatedType(wc.getBound(), wc.getBound().type);
5892                     } else {
5893                         // Nothing to do for UNBOUND
5894                     }
5895                     repeat = false;
5896                 } else if (enclTr.hasTag(TYPEARRAY)) {
5897                     JCArrayTypeTree art = (JCArrayTypeTree) enclTr;
5898                     validateAnnotatedType(art.getType(), art.elemtype.type);
5899                     repeat = false;
5900                 } else if (enclTr.hasTag(TYPEUNION)) {
5901                     JCTypeUnion ut = (JCTypeUnion) enclTr;
5902                     for (JCTree t : ut.getTypeAlternatives()) {
5903                         validateAnnotatedType(t, t.type);
5904                     }
5905                     repeat = false;
5906                 } else if (enclTr.hasTag(TYPEINTERSECTION)) {
5907                     JCTypeIntersection it = (JCTypeIntersection) enclTr;
5908                     for (JCTree t : it.getBounds()) {
5909                         validateAnnotatedType(t, t.type);
5910                     }
5911                     repeat = false;
5912                 } else if (enclTr.getKind() == JCTree.Kind.PRIMITIVE_TYPE ||
5913                            enclTr.getKind() == JCTree.Kind.ERRONEOUS) {
5914                     repeat = false;
5915                 } else {
5916                     Assert.error("Unexpected tree: " + enclTr + " with kind: " + enclTr.getKind() +
5917                             " within: "+ errtree + " with kind: " + errtree.getKind());
5918                 }
5919             }
5920         }
5921 
5922         private void checkForDeclarationAnnotations(List<? extends JCAnnotation> annotations,
5923                 Symbol sym) {
5924             // Ensure that no declaration annotations are present.
5925             // Note that a tree type might be an AnnotatedType with
5926             // empty annotations, if only declaration annotations were given.
5927             // This method will raise an error for such a type.
5928             for (JCAnnotation ai : annotations) {
5929                 if (!ai.type.isErroneous() &&
5930                         typeAnnotations.annotationTargetType(ai.attribute, sym) == TypeAnnotations.AnnotationType.DECLARATION) {
5931                     log.error(ai.pos(), Errors.AnnotationTypeNotApplicableToType(ai.type));
5932                 }
5933             }
5934         }
5935     }
5936 
5937     // <editor-fold desc="post-attribution visitor">
5938 
5939     /**
5940      * Handle missing types/symbols in an AST. This routine is useful when
5941      * the compiler has encountered some errors (which might have ended up
5942      * terminating attribution abruptly); if the compiler is used in fail-over
5943      * mode (e.g. by an IDE) and the AST contains semantic errors, this routine
5944      * prevents NPE to be propagated during subsequent compilation steps.
5945      */
5946     public void postAttr(JCTree tree) {
5947         new PostAttrAnalyzer().scan(tree);
5948     }
5949 
5950     class PostAttrAnalyzer extends TreeScanner {
5951 
5952         private void initTypeIfNeeded(JCTree that) {
5953             if (that.type == null) {
5954                 if (that.hasTag(METHODDEF)) {
5955                     that.type = dummyMethodType((JCMethodDecl)that);
5956                 } else {
5957                     that.type = syms.unknownType;
5958                 }
5959             }
5960         }
5961 
5962         /* Construct a dummy method type. If we have a method declaration,
5963          * and the declared return type is void, then use that return type
5964          * instead of UNKNOWN to avoid spurious error messages in lambda
5965          * bodies (see:JDK-8041704).
5966          */
5967         private Type dummyMethodType(JCMethodDecl md) {
5968             Type restype = syms.unknownType;
5969             if (md != null && md.restype != null && md.restype.hasTag(TYPEIDENT)) {
5970                 JCPrimitiveTypeTree prim = (JCPrimitiveTypeTree)md.restype;
5971                 if (prim.typetag == VOID)
5972                     restype = syms.voidType;
5973             }
5974             return new MethodType(List.nil(), restype,
5975                                   List.nil(), syms.methodClass);
5976         }
5977         private Type dummyMethodType() {
5978             return dummyMethodType(null);
5979         }
5980 
5981         @Override
5982         public void scan(JCTree tree) {
5983             if (tree == null) return;
5984             if (tree instanceof JCExpression) {
5985                 initTypeIfNeeded(tree);
5986             }
5987             super.scan(tree);
5988         }
5989 
5990         @Override
5991         public void visitIdent(JCIdent that) {
5992             if (that.sym == null) {
5993                 that.sym = syms.unknownSymbol;
5994             }
5995         }
5996 
5997         @Override
5998         public void visitSelect(JCFieldAccess that) {
5999             if (that.sym == null) {
6000                 that.sym = syms.unknownSymbol;
6001             }
6002             super.visitSelect(that);
6003         }
6004 
6005         @Override
6006         public void visitClassDef(JCClassDecl that) {
6007             initTypeIfNeeded(that);
6008             if (that.sym == null) {
6009                 that.sym = new ClassSymbol(0, that.name, that.type, syms.noSymbol);
6010             }
6011             super.visitClassDef(that);
6012         }
6013 
6014         @Override
6015         public void visitMethodDef(JCMethodDecl that) {
6016             initTypeIfNeeded(that);
6017             if (that.sym == null) {
6018                 that.sym = new MethodSymbol(0, that.name, that.type, syms.noSymbol);
6019             }
6020             super.visitMethodDef(that);
6021         }
6022 
6023         @Override
6024         public void visitVarDef(JCVariableDecl that) {
6025             initTypeIfNeeded(that);
6026             if (that.sym == null) {
6027                 that.sym = new VarSymbol(0, that.name, that.type, syms.noSymbol);
6028                 that.sym.adr = 0;
6029             }
6030             if (that.vartype == null) {
6031                 that.vartype = make.at(Position.NOPOS).Erroneous();
6032             }
6033             super.visitVarDef(that);
6034         }
6035 
6036         @Override
6037         public void visitBindingPattern(JCBindingPattern that) {
6038             initTypeIfNeeded(that);
6039             initTypeIfNeeded(that.var);
6040             if (that.var.sym == null) {
6041                 that.var.sym = new BindingSymbol(0, that.var.name, that.var.type, syms.noSymbol);
6042                 that.var.sym.adr = 0;
6043             }
6044             super.visitBindingPattern(that);
6045         }
6046 
6047         @Override
6048         public void visitNewClass(JCNewClass that) {
6049             if (that.constructor == null) {
6050                 that.constructor = new MethodSymbol(0, names.init,
6051                         dummyMethodType(), syms.noSymbol);
6052             }
6053             if (that.constructorType == null) {
6054                 that.constructorType = syms.unknownType;
6055             }
6056             super.visitNewClass(that);
6057         }
6058 
6059         @Override
6060         public void visitAssignop(JCAssignOp that) {
6061             if (that.operator == null) {
6062                 that.operator = new OperatorSymbol(names.empty, dummyMethodType(),
6063                         -1, syms.noSymbol);
6064             }
6065             super.visitAssignop(that);
6066         }
6067 
6068         @Override
6069         public void visitBinary(JCBinary that) {
6070             if (that.operator == null) {
6071                 that.operator = new OperatorSymbol(names.empty, dummyMethodType(),
6072                         -1, syms.noSymbol);
6073             }
6074             super.visitBinary(that);
6075         }
6076 
6077         @Override
6078         public void visitUnary(JCUnary that) {
6079             if (that.operator == null) {
6080                 that.operator = new OperatorSymbol(names.empty, dummyMethodType(),
6081                         -1, syms.noSymbol);
6082             }
6083             super.visitUnary(that);
6084         }
6085 
6086         @Override
6087         public void visitReference(JCMemberReference that) {
6088             super.visitReference(that);
6089             if (that.sym == null) {
6090                 that.sym = new MethodSymbol(0, names.empty, dummyMethodType(),
6091                         syms.noSymbol);
6092             }
6093         }
6094     }
6095     // </editor-fold>
6096 
6097     public void setPackageSymbols(JCExpression pid, Symbol pkg) {
6098         new TreeScanner() {
6099             Symbol packge = pkg;
6100             @Override
6101             public void visitIdent(JCIdent that) {
6102                 that.sym = packge;
6103             }
6104 
6105             @Override
6106             public void visitSelect(JCFieldAccess that) {
6107                 that.sym = packge;
6108                 packge = packge.owner;
6109                 super.visitSelect(that);
6110             }
6111         }.scan(pid);
6112     }
6113 
6114 }