1 /*
   2  * Copyright (c) 1999, 2021, 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.tree;
  27 
  28 
  29 
  30 import com.sun.source.tree.Tree;
  31 import com.sun.source.util.TreePath;
  32 import com.sun.tools.javac.code.*;
  33 import com.sun.tools.javac.comp.AttrContext;
  34 import com.sun.tools.javac.comp.Env;
  35 import com.sun.tools.javac.tree.JCTree.*;
  36 import com.sun.tools.javac.tree.JCTree.JCPolyExpression.*;
  37 import com.sun.tools.javac.util.*;
  38 import com.sun.tools.javac.util.JCDiagnostic.DiagnosticPosition;
  39 
  40 import static com.sun.tools.javac.code.Flags.*;
  41 import static com.sun.tools.javac.code.Kinds.Kind.*;
  42 import com.sun.tools.javac.code.Symbol.VarSymbol;
  43 import static com.sun.tools.javac.code.TypeTag.BOOLEAN;
  44 import static com.sun.tools.javac.code.TypeTag.BOT;
  45 import static com.sun.tools.javac.tree.JCTree.Tag.*;
  46 import static com.sun.tools.javac.tree.JCTree.Tag.BLOCK;
  47 import static com.sun.tools.javac.tree.JCTree.Tag.SYNCHRONIZED;
  48 
  49 import javax.tools.JavaFileObject;
  50 
  51 import java.util.function.ToIntFunction;
  52 
  53 import static com.sun.tools.javac.tree.JCTree.JCOperatorExpression.OperandPos.LEFT;
  54 import static com.sun.tools.javac.tree.JCTree.JCOperatorExpression.OperandPos.RIGHT;
  55 
  56 /** Utility class containing inspector methods for trees.
  57  *
  58  *  <p><b>This is NOT part of any supported API.
  59  *  If you write code that depends on this, you do so at your own risk.
  60  *  This code and its internal interfaces are subject to change or
  61  *  deletion without notice.</b>
  62  */
  63 public class TreeInfo {
  64 
  65     public static List<JCExpression> args(JCTree t) {
  66         switch (t.getTag()) {
  67             case APPLY:
  68                 return ((JCMethodInvocation)t).args;
  69             case NEWCLASS:
  70                 return ((JCNewClass)t).args;
  71             default:
  72                 return null;
  73         }
  74     }
  75 
  76     /** Is tree a constructor declaration?
  77      */
  78     public static boolean isConstructor(JCTree tree) {
  79         if (tree.hasTag(METHODDEF)) {
  80             Name name = ((JCMethodDecl) tree).name;
  81             return name == name.table.names.init;
  82         } else {
  83             return false;
  84         }
  85     }
  86 
  87     public static boolean isCanonicalConstructor(JCTree tree) {
  88         // the record flag is only set to the canonical constructor
  89         return isConstructor(tree) && (((JCMethodDecl)tree).sym.flags_field & RECORD) != 0;
  90     }
  91 
  92     public static boolean isCompactConstructor(JCTree tree) {
  93         // the record flag is only set to the canonical constructor
  94         return isCanonicalConstructor(tree) && (((JCMethodDecl)tree).sym.flags_field & COMPACT_RECORD_CONSTRUCTOR) != 0;
  95     }
  96 
  97     public static boolean isReceiverParam(JCTree tree) {
  98         if (tree.hasTag(VARDEF)) {
  99             return ((JCVariableDecl)tree).nameexpr != null;
 100         } else {
 101             return false;
 102         }
 103     }
 104 
 105     /** Is there a constructor declaration in the given list of trees?
 106      */
 107     public static boolean hasConstructors(List<JCTree> trees) {
 108         for (List<JCTree> l = trees; l.nonEmpty(); l = l.tail)
 109             if (isConstructor(l.head)) return true;
 110         return false;
 111     }
 112 
 113     /** Is there a constructor invocation in the given list of trees?
 114      *  Optionally, check only for no-arg ctor invocation
 115      */
 116     public static Name getConstructorInvocationName(List<? extends JCTree> trees, Names names, boolean argsAllowed) {
 117         for (JCTree tree : trees) {
 118             if (tree.hasTag(EXEC)) {
 119                 JCExpressionStatement stat = (JCExpressionStatement)tree;
 120                 if (stat.expr.hasTag(APPLY)) {
 121                     JCMethodInvocation apply = (JCMethodInvocation)stat.expr;
 122                     if (argsAllowed || apply.args.size() == 0) {
 123                         Name methName = TreeInfo.name(apply.meth);
 124                         if (methName == names._this ||
 125                                 methName == names._super) {
 126                             return methName;
 127                         }
 128                     }
 129                 }
 130             }
 131         }
 132         return names.empty;
 133     }
 134 
 135     public static boolean isMultiCatch(JCCatch catchClause) {
 136         return catchClause.param.vartype.hasTag(TYPEUNION);
 137     }
 138 
 139     /** Is statement an initializer for a synthetic field?
 140      */
 141     public static boolean isSyntheticInit(JCTree stat) {
 142         if (stat.hasTag(EXEC)) {
 143             JCExpressionStatement exec = (JCExpressionStatement)stat;
 144             if (exec.expr.hasTag(ASSIGN)) {
 145                 JCAssign assign = (JCAssign)exec.expr;
 146                 if (assign.lhs.hasTag(SELECT)) {
 147                     JCFieldAccess select = (JCFieldAccess)assign.lhs;
 148                     if (select.sym != null &&
 149                         (select.sym.flags() & SYNTHETIC) != 0) {
 150                         Name selected = name(select.selected);
 151                         if (selected != null && selected == selected.table.names._this)
 152                             return true;
 153                     }
 154                 }
 155             }
 156         }
 157         return false;
 158     }
 159 
 160     /** If the expression is a method call, return the method name, null
 161      *  otherwise. */
 162     public static Name calledMethodName(JCTree tree) {
 163         if (tree.hasTag(EXEC)) {
 164             JCExpressionStatement exec = (JCExpressionStatement)tree;
 165             if (exec.expr.hasTag(APPLY)) {
 166                 Name mname = TreeInfo.name(((JCMethodInvocation) exec.expr).meth);
 167                 return mname;
 168             }
 169         }
 170         return null;
 171     }
 172 
 173     /** Is this a call to this or super?
 174      */
 175     public static boolean isSelfCall(JCTree tree) {
 176         Name name = calledMethodName(tree);
 177         if (name != null) {
 178             Names names = name.table.names;
 179             return name==names._this || name==names._super;
 180         } else {
 181             return false;
 182         }
 183     }
 184 
 185     /** Is this tree a 'this' identifier?
 186      */
 187     public static boolean isThisQualifier(JCTree tree) {
 188         switch (tree.getTag()) {
 189             case PARENS:
 190                 return isThisQualifier(skipParens(tree));
 191             case IDENT: {
 192                 JCIdent id = (JCIdent)tree;
 193                 return id.name == id.name.table.names._this;
 194             }
 195             default:
 196                 return false;
 197         }
 198     }
 199 
 200     /** Is this tree an identifier, possibly qualified by 'this'?
 201      */
 202     public static boolean isIdentOrThisDotIdent(JCTree tree) {
 203         switch (tree.getTag()) {
 204             case PARENS:
 205                 return isIdentOrThisDotIdent(skipParens(tree));
 206             case IDENT:
 207                 return true;
 208             case SELECT:
 209                 return isThisQualifier(((JCFieldAccess)tree).selected);
 210             default:
 211                 return false;
 212         }
 213     }
 214 
 215     /** Is this a call to super?
 216      */
 217     public static boolean isSuperCall(JCTree tree) {
 218         Name name = calledMethodName(tree);
 219         if (name != null) {
 220             Names names = name.table.names;
 221             return name==names._super;
 222         } else {
 223             return false;
 224         }
 225     }
 226 
 227     public static List<JCVariableDecl> recordFields(JCClassDecl tree) {
 228         return tree.defs.stream()
 229                 .filter(t -> t.hasTag(VARDEF))
 230                 .map(t -> (JCVariableDecl)t)
 231                 .filter(vd -> (vd.getModifiers().flags & (Flags.RECORD)) == RECORD)
 232                 .collect(List.collector());
 233     }
 234 
 235     public static List<Type> recordFieldTypes(JCClassDecl tree) {
 236         return recordFields(tree).stream()
 237                 .map(vd -> vd.type)
 238                 .collect(List.collector());
 239     }
 240 
 241     /** Is this a constructor whose first (non-synthetic) statement is not
 242      *  of the form this(...)?
 243      */
 244     public static boolean isInitialConstructor(JCTree tree) {
 245         JCMethodInvocation app = firstConstructorCall(tree);
 246         if (app == null) return false;
 247         Name meth = name(app.meth);
 248         return meth == null || meth != meth.table.names._this;
 249     }
 250 
 251     /** Return the first call in a constructor definition. */
 252     public static JCMethodInvocation firstConstructorCall(JCTree tree) {
 253         if (!tree.hasTag(METHODDEF)) return null;
 254         JCMethodDecl md = (JCMethodDecl) tree;
 255         Names names = md.name.table.names;
 256         if (md.name != names.init) return null;
 257         if (md.body == null) return null;
 258         List<JCStatement> stats = md.body.stats;
 259         // Synthetic initializations can appear before the super call.
 260         while (stats.nonEmpty() && isSyntheticInit(stats.head))
 261             stats = stats.tail;
 262         if (stats.isEmpty()) return null;
 263         if (!stats.head.hasTag(EXEC)) return null;
 264         JCExpressionStatement exec = (JCExpressionStatement) stats.head;
 265         if (!exec.expr.hasTag(APPLY)) return null;
 266         return (JCMethodInvocation)exec.expr;
 267     }
 268 
 269     /** Return true if a tree represents a diamond new expr. */
 270     public static boolean isDiamond(JCTree tree) {
 271         switch(tree.getTag()) {
 272             case TYPEAPPLY: return ((JCTypeApply)tree).getTypeArguments().isEmpty();
 273             case NEWCLASS: return isDiamond(((JCNewClass)tree).clazz);
 274             case ANNOTATED_TYPE: return isDiamond(((JCAnnotatedType)tree).underlyingType);
 275             default: return false;
 276         }
 277     }
 278 
 279     public static boolean isEnumInit(JCTree tree) {
 280         switch (tree.getTag()) {
 281             case VARDEF:
 282                 return (((JCVariableDecl)tree).mods.flags & ENUM) != 0;
 283             default:
 284                 return false;
 285         }
 286     }
 287 
 288     /** set 'polyKind' on given tree */
 289     public static void setPolyKind(JCTree tree, PolyKind pkind) {
 290         switch (tree.getTag()) {
 291             case APPLY:
 292                 ((JCMethodInvocation)tree).polyKind = pkind;
 293                 break;
 294             case NEWCLASS:
 295                 ((JCNewClass)tree).polyKind = pkind;
 296                 break;
 297             case REFERENCE:
 298                 ((JCMemberReference)tree).refPolyKind = pkind;
 299                 break;
 300             default:
 301                 throw new AssertionError("Unexpected tree: " + tree);
 302         }
 303     }
 304 
 305     /** set 'varargsElement' on given tree */
 306     public static void setVarargsElement(JCTree tree, Type varargsElement) {
 307         switch (tree.getTag()) {
 308             case APPLY:
 309                 ((JCMethodInvocation)tree).varargsElement = varargsElement;
 310                 break;
 311             case NEWCLASS:
 312                 ((JCNewClass)tree).varargsElement = varargsElement;
 313                 break;
 314             case REFERENCE:
 315                 ((JCMemberReference)tree).varargsElement = varargsElement;
 316                 break;
 317             default:
 318                 throw new AssertionError("Unexpected tree: " + tree);
 319         }
 320     }
 321 
 322     /** Return true if the tree corresponds to an expression statement */
 323     public static boolean isExpressionStatement(JCExpression tree) {
 324         switch(tree.getTag()) {
 325             case PREINC: case PREDEC:
 326             case POSTINC: case POSTDEC:
 327             case ASSIGN:
 328             case BITOR_ASG: case BITXOR_ASG: case BITAND_ASG:
 329             case SL_ASG: case SR_ASG: case USR_ASG:
 330             case PLUS_ASG: case MINUS_ASG:
 331             case MUL_ASG: case DIV_ASG: case MOD_ASG:
 332             case APPLY: case NEWCLASS:
 333             case ERRONEOUS:
 334                 return true;
 335             default:
 336                 return false;
 337         }
 338     }
 339 
 340     /** Return true if the tree corresponds to a statement */
 341     public static boolean isStatement(JCTree tree) {
 342         return (tree instanceof JCStatement) &&
 343                 !tree.hasTag(CLASSDEF) &&
 344                 !tree.hasTag(Tag.BLOCK) &&
 345                 !tree.hasTag(METHODDEF);
 346     }
 347 
 348     /**
 349      * Return true if the AST corresponds to a static select of the kind A.B
 350      */
 351     public static boolean isStaticSelector(JCTree base, Names names) {
 352         if (base == null)
 353             return false;
 354         switch (base.getTag()) {
 355             case IDENT:
 356                 JCIdent id = (JCIdent)base;
 357                 return id.name != names._this &&
 358                         id.name != names._super &&
 359                         isStaticSym(base);
 360             case SELECT:
 361                 return isStaticSym(base) &&
 362                     isStaticSelector(((JCFieldAccess)base).selected, names);
 363             case TYPEAPPLY:
 364             case TYPEARRAY:
 365                 return true;
 366             case ANNOTATED_TYPE:
 367                 return isStaticSelector(((JCAnnotatedType)base).underlyingType, names);
 368             default:
 369                 return false;
 370         }
 371     }
 372     //where
 373         private static boolean isStaticSym(JCTree tree) {
 374             Symbol sym = symbol(tree);
 375             return (sym.kind == TYP || sym.kind == PCK);
 376         }
 377 
 378     /** Return true if a tree represents the null literal. */
 379     public static boolean isNull(JCTree tree) {
 380         if (!tree.hasTag(LITERAL))
 381             return false;
 382         JCLiteral lit = (JCLiteral) tree;
 383         return (lit.typetag == BOT);
 384     }
 385 
 386     /** Return true iff this tree is a child of some annotation. */
 387     public static boolean isInAnnotation(Env<?> env, JCTree tree) {
 388         TreePath tp = TreePath.getPath(env.toplevel, tree);
 389         if (tp != null) {
 390             for (Tree t : tp) {
 391                 if (t.getKind() == Tree.Kind.ANNOTATION)
 392                     return true;
 393             }
 394         }
 395         return false;
 396     }
 397 
 398     public static String getCommentText(Env<?> env, JCTree tree) {
 399         DocCommentTable docComments = (tree.hasTag(JCTree.Tag.TOPLEVEL))
 400                 ? ((JCCompilationUnit) tree).docComments
 401                 : env.toplevel.docComments;
 402         return (docComments == null) ? null : docComments.getCommentText(tree);
 403     }
 404 
 405     public static DCTree.DCDocComment getCommentTree(Env<?> env, JCTree tree) {
 406         DocCommentTable docComments = (tree.hasTag(JCTree.Tag.TOPLEVEL))
 407                 ? ((JCCompilationUnit) tree).docComments
 408                 : env.toplevel.docComments;
 409         return (docComments == null) ? null : docComments.getCommentTree(tree);
 410     }
 411 
 412     /** The position of the first statement in a block, or the position of
 413      *  the block itself if it is empty.
 414      */
 415     public static int firstStatPos(JCTree tree) {
 416         if (tree.hasTag(BLOCK) && ((JCBlock) tree).stats.nonEmpty())
 417             return ((JCBlock) tree).stats.head.pos;
 418         else
 419             return tree.pos;
 420     }
 421 
 422     /** The end position of given tree, if it is a block with
 423      *  defined endpos.
 424      */
 425     public static int endPos(JCTree tree) {
 426         if (tree.hasTag(BLOCK) && ((JCBlock) tree).endpos != Position.NOPOS)
 427             return ((JCBlock) tree).endpos;
 428         else if (tree.hasTag(SYNCHRONIZED))
 429             return endPos(((JCSynchronized) tree).body);
 430         else if (tree.hasTag(TRY)) {
 431             JCTry t = (JCTry) tree;
 432             return endPos((t.finalizer != null) ? t.finalizer
 433                           : (t.catchers.nonEmpty() ? t.catchers.last().body : t.body));
 434         } else if (tree.hasTag(SWITCH) &&
 435                    ((JCSwitch) tree).endpos != Position.NOPOS) {
 436             return ((JCSwitch) tree).endpos;
 437         } else if (tree.hasTag(SWITCH_EXPRESSION) &&
 438                    ((JCSwitchExpression) tree).endpos != Position.NOPOS) {
 439             return ((JCSwitchExpression) tree).endpos;
 440         } else
 441             return tree.pos;
 442     }
 443 
 444 
 445     /** Get the start position for a tree node.  The start position is
 446      * defined to be the position of the first character of the first
 447      * token of the node's source text.
 448      * @param tree  The tree node
 449      */
 450     public static int getStartPos(JCTree tree) {
 451         if (tree == null)
 452             return Position.NOPOS;
 453 
 454         switch(tree.getTag()) {
 455             case MODULEDEF: {
 456                 JCModuleDecl md = (JCModuleDecl)tree;
 457                 return md.mods.annotations.isEmpty() ? md.pos :
 458                        md.mods.annotations.head.pos;
 459             }
 460             case PACKAGEDEF: {
 461                 JCPackageDecl pd = (JCPackageDecl)tree;
 462                 return pd.annotations.isEmpty() ? pd.pos :
 463                        pd.annotations.head.pos;
 464             }
 465             case APPLY:
 466                 return getStartPos(((JCMethodInvocation) tree).meth);
 467             case ASSIGN:
 468                 return getStartPos(((JCAssign) tree).lhs);
 469             case BITOR_ASG: case BITXOR_ASG: case BITAND_ASG:
 470             case SL_ASG: case SR_ASG: case USR_ASG:
 471             case PLUS_ASG: case MINUS_ASG: case MUL_ASG:
 472             case DIV_ASG: case MOD_ASG:
 473             case OR: case AND: case BITOR:
 474             case BITXOR: case BITAND: case EQ:
 475             case NE: case LT: case GT:
 476             case LE: case GE: case SL:
 477             case SR: case USR: case PLUS:
 478             case MINUS: case MUL: case DIV:
 479             case MOD:
 480             case POSTINC:
 481             case POSTDEC:
 482                 return getStartPos(((JCOperatorExpression) tree).getOperand(LEFT));
 483             case CLASSDEF: {
 484                 JCClassDecl node = (JCClassDecl)tree;
 485                 if (node.mods.pos != Position.NOPOS)
 486                     return node.mods.pos;
 487                 break;
 488             }
 489             case CONDEXPR:
 490                 return getStartPos(((JCConditional) tree).cond);
 491             case DEFAULT_VALUE:
 492                 return getStartPos(((JCDefaultValue) tree).clazz);
 493             case EXEC:
 494                 return getStartPos(((JCExpressionStatement) tree).expr);
 495             case INDEXED:
 496                 return getStartPos(((JCArrayAccess) tree).indexed);
 497             case METHODDEF: {
 498                 JCMethodDecl node = (JCMethodDecl)tree;
 499                 if (node.mods.pos != Position.NOPOS)
 500                     return node.mods.pos;
 501                 if (node.typarams.nonEmpty()) // List.nil() used for no typarams
 502                     return getStartPos(node.typarams.head);
 503                 return node.restype == null ? node.pos : getStartPos(node.restype);
 504             }
 505             case SELECT:
 506                 return getStartPos(((JCFieldAccess) tree).selected);
 507             case TYPEAPPLY:
 508                 return getStartPos(((JCTypeApply) tree).clazz);
 509             case TYPEARRAY:
 510                 return getStartPos(((JCArrayTypeTree) tree).elemtype);
 511             case TYPETEST:
 512                 return getStartPos(((JCInstanceOf) tree).expr);
 513             case ANNOTATED_TYPE: {
 514                 JCAnnotatedType node = (JCAnnotatedType) tree;
 515                 if (node.annotations.nonEmpty()) {
 516                     if (node.underlyingType.hasTag(TYPEARRAY) ||
 517                             node.underlyingType.hasTag(SELECT)) {
 518                         return getStartPos(node.underlyingType);
 519                     } else {
 520                         return getStartPos(node.annotations.head);
 521                     }
 522                 } else {
 523                     return getStartPos(node.underlyingType);
 524                 }
 525             }
 526             case NEWCLASS: {
 527                 JCNewClass node = (JCNewClass)tree;
 528                 if (node.encl != null)
 529                     return getStartPos(node.encl);
 530                 break;
 531             }
 532             case VARDEF: {
 533                 JCVariableDecl node = (JCVariableDecl)tree;
 534                 if (node.startPos != Position.NOPOS) {
 535                     return node.startPos;
 536                 } else if (node.mods.pos != Position.NOPOS) {
 537                     return node.mods.pos;
 538                 } else if (node.vartype == null || node.vartype.pos == Position.NOPOS) {
 539                     //if there's no type (partially typed lambda parameter)
 540                     //simply return node position
 541                     return node.pos;
 542                 } else {
 543                     return getStartPos(node.vartype);
 544                 }
 545             }
 546             case BINDINGPATTERN: {
 547                 JCBindingPattern node = (JCBindingPattern)tree;
 548                 return getStartPos(node.var);
 549             }
 550             case GUARDPATTERN: {
 551                 JCGuardPattern node = (JCGuardPattern) tree;
 552                 return getStartPos(node.patt);
 553             }
 554             case ERRONEOUS: {
 555                 JCErroneous node = (JCErroneous)tree;
 556                 if (node.errs != null && node.errs.nonEmpty()) {
 557                     int pos = getStartPos(node.errs.head);
 558                     if (pos != Position.NOPOS) {
 559                         return pos;
 560                     }
 561                 }
 562                 break;
 563             }
 564         }
 565         return tree.pos;
 566     }
 567 
 568     /** The end position of given tree, given  a table of end positions generated by the parser
 569      */
 570     public static int getEndPos(JCTree tree, EndPosTable endPosTable) {
 571         if (tree == null)
 572             return Position.NOPOS;
 573 
 574         if (endPosTable == null) {
 575             // fall back on limited info in the tree
 576             return endPos(tree);
 577         }
 578 
 579         int mapPos = endPosTable.getEndPos(tree);
 580         if (mapPos != Position.NOPOS)
 581             return mapPos;
 582 
 583         switch(tree.getTag()) {
 584             case BITOR_ASG: case BITXOR_ASG: case BITAND_ASG:
 585             case SL_ASG: case SR_ASG: case USR_ASG:
 586             case PLUS_ASG: case MINUS_ASG: case MUL_ASG:
 587             case DIV_ASG: case MOD_ASG:
 588             case OR: case AND: case BITOR:
 589             case BITXOR: case BITAND: case EQ:
 590             case NE: case LT: case GT:
 591             case LE: case GE: case SL:
 592             case SR: case USR: case PLUS:
 593             case MINUS: case MUL: case DIV:
 594             case MOD:
 595             case POS:
 596             case NEG:
 597             case NOT:
 598             case COMPL:
 599             case PREINC:
 600             case PREDEC:
 601                 return getEndPos(((JCOperatorExpression) tree).getOperand(RIGHT), endPosTable);
 602             case CASE:
 603                 return getEndPos(((JCCase) tree).stats.last(), endPosTable);
 604             case CATCH:
 605                 return getEndPos(((JCCatch) tree).body, endPosTable);
 606             case CONDEXPR:
 607                 return getEndPos(((JCConditional) tree).falsepart, endPosTable);
 608             case FORLOOP:
 609                 return getEndPos(((JCForLoop) tree).body, endPosTable);
 610             case FOREACHLOOP:
 611                 return getEndPos(((JCEnhancedForLoop) tree).body, endPosTable);
 612             case IF: {
 613                 JCIf node = (JCIf)tree;
 614                 if (node.elsepart == null) {
 615                     return getEndPos(node.thenpart, endPosTable);
 616                 } else {
 617                     return getEndPos(node.elsepart, endPosTable);
 618                 }
 619             }
 620             case LABELLED:
 621                 return getEndPos(((JCLabeledStatement) tree).body, endPosTable);
 622             case MODIFIERS:
 623                 return getEndPos(((JCModifiers) tree).annotations.last(), endPosTable);
 624             case SYNCHRONIZED:
 625                 return getEndPos(((JCSynchronized) tree).body, endPosTable);
 626             case TOPLEVEL:
 627                 return getEndPos(((JCCompilationUnit) tree).defs.last(), endPosTable);
 628             case TRY: {
 629                 JCTry node = (JCTry)tree;
 630                 if (node.finalizer != null) {
 631                     return getEndPos(node.finalizer, endPosTable);
 632                 } else if (!node.catchers.isEmpty()) {
 633                     return getEndPos(node.catchers.last(), endPosTable);
 634                 } else {
 635                     return getEndPos(node.body, endPosTable);
 636                 }
 637             }
 638             case WILDCARD:
 639                 return getEndPos(((JCWildcard) tree).inner, endPosTable);
 640             case TYPECAST:
 641                 return getEndPos(((JCTypeCast) tree).expr, endPosTable);
 642             case TYPETEST:
 643                 return getEndPos(((JCInstanceOf) tree).pattern, endPosTable);
 644             case WITHFIELD:
 645                 return getEndPos(((JCWithField) tree).value, endPosTable);
 646             case WHILELOOP:
 647                 return getEndPos(((JCWhileLoop) tree).body, endPosTable);
 648             case ANNOTATED_TYPE:
 649                 return getEndPos(((JCAnnotatedType) tree).underlyingType, endPosTable);
 650             case PARENTHESIZEDPATTERN: {
 651                 JCParenthesizedPattern node = (JCParenthesizedPattern) tree;
 652                 return getEndPos(node.pattern, endPosTable);
 653             }
 654             case GUARDPATTERN: {
 655                 JCGuardPattern node = (JCGuardPattern) tree;
 656                 return getEndPos(node.expr, endPosTable);
 657             }
 658             case ERRONEOUS: {
 659                 JCErroneous node = (JCErroneous)tree;
 660                 if (node.errs != null && node.errs.nonEmpty())
 661                     return getEndPos(node.errs.last(), endPosTable);
 662             }
 663         }
 664         return Position.NOPOS;
 665     }
 666 
 667 
 668     /** A DiagnosticPosition with the preferred position set to the
 669      *  end position of given tree, if it is a block with
 670      *  defined endpos.
 671      */
 672     public static DiagnosticPosition diagEndPos(final JCTree tree) {
 673         final int endPos = TreeInfo.endPos(tree);
 674         return new DiagnosticPosition() {
 675             public JCTree getTree() { return tree; }
 676             public int getStartPosition() { return TreeInfo.getStartPos(tree); }
 677             public int getPreferredPosition() { return endPos; }
 678             public int getEndPosition(EndPosTable endPosTable) {
 679                 return TreeInfo.getEndPos(tree, endPosTable);
 680             }
 681         };
 682     }
 683 
 684     public enum PosKind {
 685         START_POS(TreeInfo::getStartPos),
 686         FIRST_STAT_POS(TreeInfo::firstStatPos),
 687         END_POS(TreeInfo::endPos);
 688 
 689         final ToIntFunction<JCTree> posFunc;
 690 
 691         PosKind(ToIntFunction<JCTree> posFunc) {
 692             this.posFunc = posFunc;
 693         }
 694 
 695         int toPos(JCTree tree) {
 696             return posFunc.applyAsInt(tree);
 697         }
 698     }
 699 
 700     /** The position of the finalizer of given try/synchronized statement.
 701      */
 702     public static int finalizerPos(JCTree tree, PosKind posKind) {
 703         if (tree.hasTag(TRY)) {
 704             JCTry t = (JCTry) tree;
 705             Assert.checkNonNull(t.finalizer);
 706             return posKind.toPos(t.finalizer);
 707         } else if (tree.hasTag(SYNCHRONIZED)) {
 708             return endPos(((JCSynchronized) tree).body);
 709         } else {
 710             throw new AssertionError();
 711         }
 712     }
 713 
 714     /** Find the position for reporting an error about a symbol, where
 715      *  that symbol is defined somewhere in the given tree. */
 716     public static int positionFor(final Symbol sym, final JCTree tree) {
 717         JCTree decl = declarationFor(sym, tree);
 718         return ((decl != null) ? decl : tree).pos;
 719     }
 720 
 721     /** Find the position for reporting an error about a symbol, where
 722      *  that symbol is defined somewhere in the given tree. */
 723     public static DiagnosticPosition diagnosticPositionFor(final Symbol sym, final JCTree tree) {
 724         return diagnosticPositionFor(sym, tree, false);
 725     }
 726 
 727     public static DiagnosticPosition diagnosticPositionFor(final Symbol sym, final JCTree tree, boolean returnNullIfNotFound) {
 728         class DiagScanner extends DeclScanner {
 729             DiagScanner(Symbol sym) {
 730                 super(sym);
 731             }
 732 
 733             public void visitIdent(JCIdent that) {
 734                 if (that.sym == sym) result = that;
 735                 else super.visitIdent(that);
 736             }
 737             public void visitSelect(JCFieldAccess that) {
 738                 if (that.sym == sym) result = that;
 739                 else super.visitSelect(that);
 740             }
 741         }
 742         DiagScanner s = new DiagScanner(sym);
 743         tree.accept(s);
 744         JCTree decl = s.result;
 745         if (decl == null && returnNullIfNotFound) { return null; }
 746         return ((decl != null) ? decl : tree).pos();
 747     }
 748 
 749     public static DiagnosticPosition diagnosticPositionFor(final Symbol sym, final List<? extends JCTree> trees) {
 750         return trees.stream().map(t -> TreeInfo.diagnosticPositionFor(sym, t)).filter(t -> t != null).findFirst().get();
 751     }
 752 
 753     private static class DeclScanner extends TreeScanner {
 754         final Symbol sym;
 755 
 756         DeclScanner(final Symbol sym) {
 757             this.sym = sym;
 758         }
 759 
 760         JCTree result = null;
 761         public void scan(JCTree tree) {
 762             if (tree!=null && result==null)
 763                 tree.accept(this);
 764         }
 765         public void visitTopLevel(JCCompilationUnit that) {
 766             if (that.packge == sym) result = that;
 767             else super.visitTopLevel(that);
 768         }
 769         public void visitModuleDef(JCModuleDecl that) {
 770             if (that.sym == sym) result = that;
 771             // no need to scan within module declaration
 772         }
 773         public void visitPackageDef(JCPackageDecl that) {
 774             if (that.packge == sym) result = that;
 775             else super.visitPackageDef(that);
 776         }
 777         public void visitClassDef(JCClassDecl that) {
 778             if (that.sym == sym) result = that;
 779             else super.visitClassDef(that);
 780         }
 781         public void visitMethodDef(JCMethodDecl that) {
 782             if (that.sym == sym) result = that;
 783             else super.visitMethodDef(that);
 784         }
 785         public void visitVarDef(JCVariableDecl that) {
 786             if (that.sym == sym) result = that;
 787             else super.visitVarDef(that);
 788         }
 789         public void visitTypeParameter(JCTypeParameter that) {
 790             if (that.type != null && that.type.tsym == sym) result = that;
 791             else super.visitTypeParameter(that);
 792         }
 793     }
 794 
 795     /** Find the declaration for a symbol, where
 796      *  that symbol is defined somewhere in the given tree. */
 797     public static JCTree declarationFor(final Symbol sym, final JCTree tree) {
 798         DeclScanner s = new DeclScanner(sym);
 799         tree.accept(s);
 800         return s.result;
 801     }
 802 
 803     public static Env<AttrContext> scopeFor(JCTree node, JCCompilationUnit unit) {
 804         return scopeFor(pathFor(node, unit));
 805     }
 806 
 807     public static Env<AttrContext> scopeFor(List<JCTree> path) {
 808         // TODO: not implemented yet
 809         throw new UnsupportedOperationException("not implemented yet");
 810     }
 811 
 812     public static List<JCTree> pathFor(final JCTree node, final JCCompilationUnit unit) {
 813         class Result extends Error {
 814             static final long serialVersionUID = -5942088234594905625L;
 815             @SuppressWarnings("serial") // List not statically Serilizable
 816             List<JCTree> path;
 817             Result(List<JCTree> path) {
 818                 this.path = path;
 819             }
 820         }
 821         class PathFinder extends TreeScanner {
 822             List<JCTree> path = List.nil();
 823             public void scan(JCTree tree) {
 824                 if (tree != null) {
 825                     path = path.prepend(tree);
 826                     if (tree == node)
 827                         throw new Result(path);
 828                     super.scan(tree);
 829                     path = path.tail;
 830                 }
 831             }
 832         }
 833         try {
 834             new PathFinder().scan(unit);
 835         } catch (Result result) {
 836             return result.path;
 837         }
 838         return List.nil();
 839     }
 840 
 841     /** Return the statement referenced by a label.
 842      *  If the label refers to a loop or switch, return that switch
 843      *  otherwise return the labelled statement itself
 844      */
 845     public static JCTree referencedStatement(JCLabeledStatement tree) {
 846         JCTree t = tree;
 847         do t = ((JCLabeledStatement) t).body;
 848         while (t.hasTag(LABELLED));
 849         switch (t.getTag()) {
 850         case DOLOOP: case WHILELOOP: case FORLOOP: case FOREACHLOOP: case SWITCH:
 851             return t;
 852         default:
 853             return tree;
 854         }
 855     }
 856 
 857     /** Skip parens and return the enclosed expression
 858      */
 859     public static JCExpression skipParens(JCExpression tree) {
 860         while (tree.hasTag(PARENS)) {
 861             tree = ((JCParens) tree).expr;
 862         }
 863         return tree;
 864     }
 865 
 866     /** Skip parens and return the enclosed expression
 867      */
 868     public static JCTree skipParens(JCTree tree) {
 869         if (tree.hasTag(PARENS))
 870             return skipParens((JCParens)tree);
 871         else
 872             return tree;
 873     }
 874 
 875     /** Return the types of a list of trees.
 876      */
 877     public static List<Type> types(List<? extends JCTree> trees) {
 878         ListBuffer<Type> ts = new ListBuffer<>();
 879         for (List<? extends JCTree> l = trees; l.nonEmpty(); l = l.tail)
 880             ts.append(l.head.type);
 881         return ts.toList();
 882     }
 883 
 884     /** If this tree is an identifier or a field or a parameterized type,
 885      *  return its name, otherwise return null.
 886      */
 887     public static Name name(JCTree tree) {
 888         switch (tree.getTag()) {
 889         case IDENT:
 890             return ((JCIdent) tree).name;
 891         case SELECT:
 892             return ((JCFieldAccess) tree).name;
 893         case TYPEAPPLY:
 894             return name(((JCTypeApply) tree).clazz);
 895         default:
 896             return null;
 897         }
 898     }
 899 
 900     /** If this tree is a qualified identifier, its return fully qualified name,
 901      *  otherwise return null.
 902      */
 903     public static Name fullName(JCTree tree) {
 904         tree = skipParens(tree);
 905         switch (tree.getTag()) {
 906         case IDENT:
 907             return ((JCIdent) tree).name;
 908         case SELECT:
 909             Name sname = fullName(((JCFieldAccess) tree).selected);
 910             return sname == null ? null : sname.append('.', name(tree));
 911         default:
 912             return null;
 913         }
 914     }
 915 
 916     public static Symbol symbolFor(JCTree node) {
 917         Symbol sym = symbolForImpl(node);
 918 
 919         return sym != null ? sym.baseSymbol() : null;
 920     }
 921 
 922     private static Symbol symbolForImpl(JCTree node) {
 923         node = skipParens(node);
 924         switch (node.getTag()) {
 925         case TOPLEVEL:
 926             JCCompilationUnit cut = (JCCompilationUnit) node;
 927             JCModuleDecl moduleDecl = cut.getModuleDecl();
 928             if (isModuleInfo(cut) && moduleDecl != null)
 929                 return symbolFor(moduleDecl);
 930             return cut.packge;
 931         case MODULEDEF:
 932             return ((JCModuleDecl) node).sym;
 933         case PACKAGEDEF:
 934             return ((JCPackageDecl) node).packge;
 935         case CLASSDEF:
 936             return ((JCClassDecl) node).sym;
 937         case METHODDEF:
 938             return ((JCMethodDecl) node).sym;
 939         case VARDEF:
 940             return ((JCVariableDecl) node).sym;
 941         case IDENT:
 942             return ((JCIdent) node).sym;
 943         case SELECT:
 944             return ((JCFieldAccess) node).sym;
 945         case REFERENCE:
 946             return ((JCMemberReference) node).sym;
 947         case NEWCLASS:
 948             return ((JCNewClass) node).constructor;
 949         case APPLY:
 950             return symbolFor(((JCMethodInvocation) node).meth);
 951         case TYPEAPPLY:
 952             return symbolFor(((JCTypeApply) node).clazz);
 953         case ANNOTATION:
 954         case TYPE_ANNOTATION:
 955         case TYPEPARAMETER:
 956             if (node.type != null)
 957                 return node.type.tsym;
 958             return null;
 959         default:
 960             return null;
 961         }
 962     }
 963 
 964     public static boolean isDeclaration(JCTree node) {
 965         node = skipParens(node);
 966         switch (node.getTag()) {
 967         case PACKAGEDEF:
 968         case CLASSDEF:
 969         case METHODDEF:
 970         case VARDEF:
 971             return true;
 972         default:
 973             return false;
 974         }
 975     }
 976 
 977     /** If this tree is an identifier or a field, return its symbol,
 978      *  otherwise return null.
 979      */
 980     public static Symbol symbol(JCTree tree) {
 981         tree = skipParens(tree);
 982         switch (tree.getTag()) {
 983         case IDENT:
 984             return ((JCIdent) tree).sym;
 985         case SELECT:
 986             return ((JCFieldAccess) tree).sym;
 987         case TYPEAPPLY:
 988             return symbol(((JCTypeApply) tree).clazz);
 989         case ANNOTATED_TYPE:
 990             return symbol(((JCAnnotatedType) tree).underlyingType);
 991         case REFERENCE:
 992             return ((JCMemberReference) tree).sym;
 993         default:
 994             return null;
 995         }
 996     }
 997 
 998     /** If this tree has a modifiers field, return it otherwise return null
 999      */
1000     public static JCModifiers getModifiers(JCTree tree) {
1001         tree = skipParens(tree);
1002         switch (tree.getTag()) {
1003             case VARDEF:
1004                 return ((JCVariableDecl) tree).mods;
1005             case METHODDEF:
1006                 return ((JCMethodDecl) tree).mods;
1007             case CLASSDEF:
1008                 return ((JCClassDecl) tree).mods;
1009             case MODULEDEF:
1010                 return ((JCModuleDecl) tree).mods;
1011         default:
1012             return null;
1013         }
1014     }
1015 
1016     /** Return true if this is a nonstatic selection. */
1017     public static boolean nonstaticSelect(JCTree tree) {
1018         tree = skipParens(tree);
1019         if (!tree.hasTag(SELECT)) return false;
1020         JCFieldAccess s = (JCFieldAccess) tree;
1021         Symbol e = symbol(s.selected);
1022         return e == null || (e.kind != PCK && e.kind != TYP);
1023     }
1024 
1025     /** If this tree is an identifier or a field, set its symbol, otherwise skip.
1026      */
1027     public static void setSymbol(JCTree tree, Symbol sym) {
1028         tree = skipParens(tree);
1029         switch (tree.getTag()) {
1030         case IDENT:
1031             ((JCIdent) tree).sym = sym; break;
1032         case SELECT:
1033             ((JCFieldAccess) tree).sym = sym; break;
1034         default:
1035         }
1036     }
1037 
1038     /** If this tree is a declaration or a block, return its flags field,
1039      *  otherwise return 0.
1040      */
1041     public static long flags(JCTree tree) {
1042         switch (tree.getTag()) {
1043         case VARDEF:
1044             return ((JCVariableDecl) tree).mods.flags;
1045         case METHODDEF:
1046             return ((JCMethodDecl) tree).mods.flags;
1047         case CLASSDEF:
1048             return ((JCClassDecl) tree).mods.flags;
1049         case BLOCK:
1050             return ((JCBlock) tree).flags;
1051         default:
1052             return 0;
1053         }
1054     }
1055 
1056     /** Return first (smallest) flag in `flags':
1057      *  pre: flags != 0
1058      */
1059     public static long firstFlag(long flags) {
1060         long flag = 1;
1061         while ((flag & flags) == 0)
1062             flag = flag << 1;
1063         return flag;
1064     }
1065 
1066     /** Return flags as a string, separated by " ".
1067      */
1068     public static String flagNames(long flags) {
1069         return Flags.toString(flags & ExtendedStandardFlags).trim();
1070     }
1071 
1072     /** Operator precedences values.
1073      */
1074     public static final int
1075         notExpression = -1,   // not an expression
1076         noPrec = 0,           // no enclosing expression
1077         assignPrec = 1,
1078         assignopPrec = 2,
1079         condPrec = 3,
1080         orPrec = 4,
1081         andPrec = 5,
1082         bitorPrec = 6,
1083         bitxorPrec = 7,
1084         bitandPrec = 8,
1085         eqPrec = 9,
1086         ordPrec = 10,
1087         shiftPrec = 11,
1088         addPrec = 12,
1089         mulPrec = 13,
1090         prefixPrec = 14,
1091         postfixPrec = 15,
1092         precCount = 16;
1093 
1094 
1095     /** Map operators to their precedence levels.
1096      */
1097     public static int opPrec(JCTree.Tag op) {
1098         switch(op) {
1099         case POS:
1100         case NEG:
1101         case NOT:
1102         case COMPL:
1103         case PREINC:
1104         case PREDEC: return prefixPrec;
1105         case POSTINC:
1106         case POSTDEC:
1107         case NULLCHK: return postfixPrec;
1108         case ASSIGN: return assignPrec;
1109         case BITOR_ASG:
1110         case BITXOR_ASG:
1111         case BITAND_ASG:
1112         case SL_ASG:
1113         case SR_ASG:
1114         case USR_ASG:
1115         case PLUS_ASG:
1116         case MINUS_ASG:
1117         case MUL_ASG:
1118         case DIV_ASG:
1119         case MOD_ASG: return assignopPrec;
1120         case OR: return orPrec;
1121         case AND: return andPrec;
1122         case EQ:
1123         case NE: return eqPrec;
1124         case LT:
1125         case GT:
1126         case LE:
1127         case GE: return ordPrec;
1128         case BITOR: return bitorPrec;
1129         case BITXOR: return bitxorPrec;
1130         case BITAND: return bitandPrec;
1131         case SL:
1132         case SR:
1133         case USR: return shiftPrec;
1134         case PLUS:
1135         case MINUS: return addPrec;
1136         case MUL:
1137         case DIV:
1138         case MOD: return mulPrec;
1139         case TYPETEST: return ordPrec;
1140         default: throw new AssertionError();
1141         }
1142     }
1143 
1144     static Tree.Kind tagToKind(JCTree.Tag tag) {
1145         switch (tag) {
1146         // Postfix expressions
1147         case POSTINC:           // _ ++
1148             return Tree.Kind.POSTFIX_INCREMENT;
1149         case POSTDEC:           // _ --
1150             return Tree.Kind.POSTFIX_DECREMENT;
1151 
1152         // Unary operators
1153         case PREINC:            // ++ _
1154             return Tree.Kind.PREFIX_INCREMENT;
1155         case PREDEC:            // -- _
1156             return Tree.Kind.PREFIX_DECREMENT;
1157         case POS:               // +
1158             return Tree.Kind.UNARY_PLUS;
1159         case NEG:               // -
1160             return Tree.Kind.UNARY_MINUS;
1161         case COMPL:             // ~
1162             return Tree.Kind.BITWISE_COMPLEMENT;
1163         case NOT:               // !
1164             return Tree.Kind.LOGICAL_COMPLEMENT;
1165 
1166         // Binary operators
1167 
1168         // Multiplicative operators
1169         case MUL:               // *
1170             return Tree.Kind.MULTIPLY;
1171         case DIV:               // /
1172             return Tree.Kind.DIVIDE;
1173         case MOD:               // %
1174             return Tree.Kind.REMAINDER;
1175 
1176         // Additive operators
1177         case PLUS:              // +
1178             return Tree.Kind.PLUS;
1179         case MINUS:             // -
1180             return Tree.Kind.MINUS;
1181 
1182         // Shift operators
1183         case SL:                // <<
1184             return Tree.Kind.LEFT_SHIFT;
1185         case SR:                // >>
1186             return Tree.Kind.RIGHT_SHIFT;
1187         case USR:               // >>>
1188             return Tree.Kind.UNSIGNED_RIGHT_SHIFT;
1189 
1190         // Relational operators
1191         case LT:                // <
1192             return Tree.Kind.LESS_THAN;
1193         case GT:                // >
1194             return Tree.Kind.GREATER_THAN;
1195         case LE:                // <=
1196             return Tree.Kind.LESS_THAN_EQUAL;
1197         case GE:                // >=
1198             return Tree.Kind.GREATER_THAN_EQUAL;
1199 
1200         // Equality operators
1201         case EQ:                // ==
1202             return Tree.Kind.EQUAL_TO;
1203         case NE:                // !=
1204             return Tree.Kind.NOT_EQUAL_TO;
1205 
1206         // Bitwise and logical operators
1207         case BITAND:            // &
1208             return Tree.Kind.AND;
1209         case BITXOR:            // ^
1210             return Tree.Kind.XOR;
1211         case BITOR:             // |
1212             return Tree.Kind.OR;
1213 
1214         // Conditional operators
1215         case AND:               // &&
1216             return Tree.Kind.CONDITIONAL_AND;
1217         case OR:                // ||
1218             return Tree.Kind.CONDITIONAL_OR;
1219 
1220         // Assignment operators
1221         case MUL_ASG:           // *=
1222             return Tree.Kind.MULTIPLY_ASSIGNMENT;
1223         case DIV_ASG:           // /=
1224             return Tree.Kind.DIVIDE_ASSIGNMENT;
1225         case MOD_ASG:           // %=
1226             return Tree.Kind.REMAINDER_ASSIGNMENT;
1227         case PLUS_ASG:          // +=
1228             return Tree.Kind.PLUS_ASSIGNMENT;
1229         case MINUS_ASG:         // -=
1230             return Tree.Kind.MINUS_ASSIGNMENT;
1231         case SL_ASG:            // <<=
1232             return Tree.Kind.LEFT_SHIFT_ASSIGNMENT;
1233         case SR_ASG:            // >>=
1234             return Tree.Kind.RIGHT_SHIFT_ASSIGNMENT;
1235         case USR_ASG:           // >>>=
1236             return Tree.Kind.UNSIGNED_RIGHT_SHIFT_ASSIGNMENT;
1237         case BITAND_ASG:        // &=
1238             return Tree.Kind.AND_ASSIGNMENT;
1239         case BITXOR_ASG:        // ^=
1240             return Tree.Kind.XOR_ASSIGNMENT;
1241         case BITOR_ASG:         // |=
1242             return Tree.Kind.OR_ASSIGNMENT;
1243 
1244         // Null check (implementation detail), for example, __.getClass()
1245         case NULLCHK:
1246             return Tree.Kind.OTHER;
1247 
1248         case ANNOTATION:
1249             return Tree.Kind.ANNOTATION;
1250         case TYPE_ANNOTATION:
1251             return Tree.Kind.TYPE_ANNOTATION;
1252 
1253         case EXPORTS:
1254             return Tree.Kind.EXPORTS;
1255         case OPENS:
1256             return Tree.Kind.OPENS;
1257 
1258         default:
1259             return null;
1260         }
1261     }
1262 
1263     /**
1264      * Returns the underlying type of the tree if it is an annotated type,
1265      * or the tree itself otherwise.
1266      */
1267     public static JCExpression typeIn(JCExpression tree) {
1268         switch (tree.getTag()) {
1269         case ANNOTATED_TYPE:
1270             return ((JCAnnotatedType)tree).underlyingType;
1271         case IDENT: /* simple names */
1272         case TYPEIDENT: /* primitive name */
1273         case SELECT: /* qualified name */
1274         case TYPEARRAY: /* array types */
1275         case WILDCARD: /* wild cards */
1276         case TYPEPARAMETER: /* type parameters */
1277         case TYPEAPPLY: /* parameterized types */
1278         case ERRONEOUS: /* error tree TODO: needed for BadCast JSR308 test case. Better way? */
1279             return tree;
1280         default:
1281             throw new AssertionError("Unexpected type tree: " + tree);
1282         }
1283     }
1284 
1285     /* Return the inner-most type of a type tree.
1286      * For an array that contains an annotated type, return that annotated type.
1287      * TODO: currently only used by Pretty. Describe behavior better.
1288      */
1289     public static JCTree innermostType(JCTree type, boolean skipAnnos) {
1290         JCTree lastAnnotatedType = null;
1291         JCTree cur = type;
1292         loop: while (true) {
1293             switch (cur.getTag()) {
1294             case TYPEARRAY:
1295                 lastAnnotatedType = null;
1296                 cur = ((JCArrayTypeTree)cur).elemtype;
1297                 break;
1298             case WILDCARD:
1299                 lastAnnotatedType = null;
1300                 cur = ((JCWildcard)cur).inner;
1301                 break;
1302             case ANNOTATED_TYPE:
1303                 lastAnnotatedType = cur;
1304                 cur = ((JCAnnotatedType)cur).underlyingType;
1305                 break;
1306             default:
1307                 break loop;
1308             }
1309         }
1310         if (!skipAnnos && lastAnnotatedType!=null) {
1311             return lastAnnotatedType;
1312         } else {
1313             return cur;
1314         }
1315     }
1316 
1317     private static class TypeAnnotationFinder extends TreeScanner {
1318         public boolean foundTypeAnno = false;
1319 
1320         @Override
1321         public void scan(JCTree tree) {
1322             if (foundTypeAnno || tree == null)
1323                 return;
1324             super.scan(tree);
1325         }
1326 
1327         public void visitAnnotation(JCAnnotation tree) {
1328             foundTypeAnno = foundTypeAnno || tree.hasTag(TYPE_ANNOTATION);
1329         }
1330     }
1331 
1332     public static boolean containsTypeAnnotation(JCTree e) {
1333         TypeAnnotationFinder finder = new TypeAnnotationFinder();
1334         finder.scan(e);
1335         return finder.foundTypeAnno;
1336     }
1337 
1338     public static boolean isModuleInfo(JCCompilationUnit tree) {
1339         return tree.sourcefile.isNameCompatible("module-info", JavaFileObject.Kind.SOURCE)
1340                 && tree.getModuleDecl() != null;
1341     }
1342 
1343     public static JCModuleDecl getModule(JCCompilationUnit t) {
1344         if (t.defs.nonEmpty()) {
1345             JCTree def = t.defs.head;
1346             if (def.hasTag(MODULEDEF))
1347                 return (JCModuleDecl) def;
1348         }
1349         return null;
1350     }
1351 
1352     public static boolean isPackageInfo(JCCompilationUnit tree) {
1353         return tree.sourcefile.isNameCompatible("package-info", JavaFileObject.Kind.SOURCE);
1354     }
1355 
1356     public static boolean isErrorEnumSwitch(JCExpression selector, List<JCCase> cases) {
1357         return selector.type.tsym.kind == Kinds.Kind.ERR &&
1358                cases.stream().flatMap(c -> c.labels.stream())
1359                              .allMatch(p -> p.hasTag(IDENT));
1360     }
1361 
1362     public static PatternPrimaryType primaryPatternType(JCPattern pat) {
1363         return switch (pat.getTag()) {
1364             case BINDINGPATTERN -> new PatternPrimaryType(((JCBindingPattern) pat).type, true);
1365             case GUARDPATTERN -> {
1366                 JCGuardPattern guarded = (JCGuardPattern) pat;
1367                 PatternPrimaryType nested = primaryPatternType(guarded.patt);
1368                 boolean unconditional = nested.unconditional();
1369                 if (guarded.expr.type.hasTag(BOOLEAN) && unconditional) {
1370                     unconditional = false;
1371                     var constValue = guarded.expr.type.constValue();
1372                     if (constValue != null && ((int) constValue) == 1) {
1373                         unconditional = true;
1374                     }
1375                 }
1376                 yield new PatternPrimaryType(nested.type(), unconditional);
1377             }
1378             case PARENTHESIZEDPATTERN -> primaryPatternType(((JCParenthesizedPattern) pat).pattern);
1379             default -> throw new AssertionError();
1380         };
1381     }
1382 
1383     public static JCBindingPattern primaryPatternTree(JCPattern pat) {
1384         return switch (pat.getTag()) {
1385             case BINDINGPATTERN -> (JCBindingPattern) pat;
1386             case GUARDPATTERN -> primaryPatternTree(((JCGuardPattern) pat).patt);
1387             case PARENTHESIZEDPATTERN -> primaryPatternTree(((JCParenthesizedPattern) pat).pattern);
1388             default -> throw new AssertionError();
1389         };
1390     }
1391 
1392     public record PatternPrimaryType(Type type, boolean unconditional) {}
1393 
1394 }