Lower.java revision 2571:10fc81ac75b4
1/* 2 * Copyright (c) 1999, 2014, 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 26package com.sun.tools.javac.comp; 27 28import java.util.*; 29 30import com.sun.tools.javac.code.*; 31import com.sun.tools.javac.code.Scope.WriteableScope; 32import com.sun.tools.javac.jvm.*; 33import com.sun.tools.javac.main.Option.PkgInfo; 34import com.sun.tools.javac.tree.*; 35import com.sun.tools.javac.util.*; 36import com.sun.tools.javac.util.JCDiagnostic.DiagnosticPosition; 37import com.sun.tools.javac.util.List; 38 39import com.sun.tools.javac.code.Symbol.*; 40import com.sun.tools.javac.tree.JCTree.*; 41import com.sun.tools.javac.code.Type.*; 42 43import com.sun.tools.javac.jvm.Target; 44import com.sun.tools.javac.tree.EndPosTable; 45 46import static com.sun.tools.javac.code.Flags.*; 47import static com.sun.tools.javac.code.Flags.BLOCK; 48import static com.sun.tools.javac.code.Kinds.*; 49import static com.sun.tools.javac.code.Scope.LookupKind.NON_RECURSIVE; 50import static com.sun.tools.javac.code.TypeTag.*; 51import static com.sun.tools.javac.jvm.ByteCodes.*; 52import static com.sun.tools.javac.tree.JCTree.Tag.*; 53 54/** This pass translates away some syntactic sugar: inner classes, 55 * class literals, assertions, foreach loops, etc. 56 * 57 * <p><b>This is NOT part of any supported API. 58 * If you write code that depends on this, you do so at your own risk. 59 * This code and its internal interfaces are subject to change or 60 * deletion without notice.</b> 61 */ 62public class Lower extends TreeTranslator { 63 protected static final Context.Key<Lower> lowerKey = new Context.Key<>(); 64 65 public static Lower instance(Context context) { 66 Lower instance = context.get(lowerKey); 67 if (instance == null) 68 instance = new Lower(context); 69 return instance; 70 } 71 72 private final Names names; 73 private final Log log; 74 private final Symtab syms; 75 private final Resolve rs; 76 private final Check chk; 77 private final Attr attr; 78 private TreeMaker make; 79 private DiagnosticPosition make_pos; 80 private final ClassWriter writer; 81 private final ConstFold cfolder; 82 private final Target target; 83 private final Source source; 84 private final TypeEnvs typeEnvs; 85 private final Name dollarAssertionsDisabled; 86 private final Name classDollar; 87 private final Types types; 88 private final boolean debugLower; 89 private final PkgInfo pkginfoOpt; 90 91 protected Lower(Context context) { 92 context.put(lowerKey, this); 93 names = Names.instance(context); 94 log = Log.instance(context); 95 syms = Symtab.instance(context); 96 rs = Resolve.instance(context); 97 chk = Check.instance(context); 98 attr = Attr.instance(context); 99 make = TreeMaker.instance(context); 100 writer = ClassWriter.instance(context); 101 cfolder = ConstFold.instance(context); 102 target = Target.instance(context); 103 source = Source.instance(context); 104 typeEnvs = TypeEnvs.instance(context); 105 dollarAssertionsDisabled = names. 106 fromString(target.syntheticNameChar() + "assertionsDisabled"); 107 classDollar = names. 108 fromString("class" + target.syntheticNameChar()); 109 110 types = Types.instance(context); 111 Options options = Options.instance(context); 112 debugLower = options.isSet("debuglower"); 113 pkginfoOpt = PkgInfo.get(options); 114 } 115 116 /** The currently enclosing class. 117 */ 118 ClassSymbol currentClass; 119 120 /** A queue of all translated classes. 121 */ 122 ListBuffer<JCTree> translated; 123 124 /** Environment for symbol lookup, set by translateTopLevelClass. 125 */ 126 Env<AttrContext> attrEnv; 127 128 /** A hash table mapping syntax trees to their ending source positions. 129 */ 130 EndPosTable endPosTable; 131 132/************************************************************************** 133 * Global mappings 134 *************************************************************************/ 135 136 /** A hash table mapping local classes to their definitions. 137 */ 138 Map<ClassSymbol, JCClassDecl> classdefs; 139 140 /** A hash table mapping local classes to a list of pruned trees. 141 */ 142 public Map<ClassSymbol, List<JCTree>> prunedTree = new WeakHashMap<>(); 143 144 /** A hash table mapping virtual accessed symbols in outer subclasses 145 * to the actually referred symbol in superclasses. 146 */ 147 Map<Symbol,Symbol> actualSymbols; 148 149 /** The current method definition. 150 */ 151 JCMethodDecl currentMethodDef; 152 153 /** The current method symbol. 154 */ 155 MethodSymbol currentMethodSym; 156 157 /** The currently enclosing outermost class definition. 158 */ 159 JCClassDecl outermostClassDef; 160 161 /** The currently enclosing outermost member definition. 162 */ 163 JCTree outermostMemberDef; 164 165 /** A map from local variable symbols to their translation (as per LambdaToMethod). 166 * This is required when a capturing local class is created from a lambda (in which 167 * case the captured symbols should be replaced with the translated lambda symbols). 168 */ 169 Map<Symbol, Symbol> lambdaTranslationMap = null; 170 171 /** A navigator class for assembling a mapping from local class symbols 172 * to class definition trees. 173 * There is only one case; all other cases simply traverse down the tree. 174 */ 175 class ClassMap extends TreeScanner { 176 177 /** All encountered class defs are entered into classdefs table. 178 */ 179 public void visitClassDef(JCClassDecl tree) { 180 classdefs.put(tree.sym, tree); 181 super.visitClassDef(tree); 182 } 183 } 184 ClassMap classMap = new ClassMap(); 185 186 /** Map a class symbol to its definition. 187 * @param c The class symbol of which we want to determine the definition. 188 */ 189 JCClassDecl classDef(ClassSymbol c) { 190 // First lookup the class in the classdefs table. 191 JCClassDecl def = classdefs.get(c); 192 if (def == null && outermostMemberDef != null) { 193 // If this fails, traverse outermost member definition, entering all 194 // local classes into classdefs, and try again. 195 classMap.scan(outermostMemberDef); 196 def = classdefs.get(c); 197 } 198 if (def == null) { 199 // If this fails, traverse outermost class definition, entering all 200 // local classes into classdefs, and try again. 201 classMap.scan(outermostClassDef); 202 def = classdefs.get(c); 203 } 204 return def; 205 } 206 207 /** A hash table mapping class symbols to lists of free variables. 208 * accessed by them. Only free variables of the method immediately containing 209 * a class are associated with that class. 210 */ 211 Map<ClassSymbol,List<VarSymbol>> freevarCache; 212 213 /** A navigator class for collecting the free variables accessed 214 * from a local class. There is only one case; all other cases simply 215 * traverse down the tree. This class doesn't deal with the specific 216 * of Lower - it's an abstract visitor that is meant to be reused in 217 * order to share the local variable capture logic. 218 */ 219 abstract class BasicFreeVarCollector extends TreeScanner { 220 221 /** Add all free variables of class c to fvs list 222 * unless they are already there. 223 */ 224 abstract void addFreeVars(ClassSymbol c); 225 226 /** If tree refers to a variable in owner of local class, add it to 227 * free variables list. 228 */ 229 public void visitIdent(JCIdent tree) { 230 visitSymbol(tree.sym); 231 } 232 // where 233 abstract void visitSymbol(Symbol _sym); 234 235 /** If tree refers to a class instance creation expression 236 * add all free variables of the freshly created class. 237 */ 238 public void visitNewClass(JCNewClass tree) { 239 ClassSymbol c = (ClassSymbol)tree.constructor.owner; 240 addFreeVars(c); 241 super.visitNewClass(tree); 242 } 243 244 /** If tree refers to a superclass constructor call, 245 * add all free variables of the superclass. 246 */ 247 public void visitApply(JCMethodInvocation tree) { 248 if (TreeInfo.name(tree.meth) == names._super) { 249 addFreeVars((ClassSymbol) TreeInfo.symbol(tree.meth).owner); 250 } 251 super.visitApply(tree); 252 } 253 } 254 255 /** 256 * Lower-specific subclass of {@code BasicFreeVarCollector}. 257 */ 258 class FreeVarCollector extends BasicFreeVarCollector { 259 260 /** The owner of the local class. 261 */ 262 Symbol owner; 263 264 /** The local class. 265 */ 266 ClassSymbol clazz; 267 268 /** The list of owner's variables accessed from within the local class, 269 * without any duplicates. 270 */ 271 List<VarSymbol> fvs; 272 273 FreeVarCollector(ClassSymbol clazz) { 274 this.clazz = clazz; 275 this.owner = clazz.owner; 276 this.fvs = List.nil(); 277 } 278 279 /** Add free variable to fvs list unless it is already there. 280 */ 281 private void addFreeVar(VarSymbol v) { 282 for (List<VarSymbol> l = fvs; l.nonEmpty(); l = l.tail) 283 if (l.head == v) return; 284 fvs = fvs.prepend(v); 285 } 286 287 @Override 288 void addFreeVars(ClassSymbol c) { 289 List<VarSymbol> fvs = freevarCache.get(c); 290 if (fvs != null) { 291 for (List<VarSymbol> l = fvs; l.nonEmpty(); l = l.tail) { 292 addFreeVar(l.head); 293 } 294 } 295 } 296 297 @Override 298 void visitSymbol(Symbol _sym) { 299 Symbol sym = _sym; 300 if (sym.kind == VAR || sym.kind == MTH) { 301 while (sym != null && sym.owner != owner) 302 sym = proxies.findFirst(proxyName(sym.name)); 303 if (sym != null && sym.owner == owner) { 304 VarSymbol v = (VarSymbol)sym; 305 if (v.getConstValue() == null) { 306 addFreeVar(v); 307 } 308 } else { 309 if (outerThisStack.head != null && 310 outerThisStack.head != _sym) 311 visitSymbol(outerThisStack.head); 312 } 313 } 314 } 315 316 /** If tree refers to a class instance creation expression 317 * add all free variables of the freshly created class. 318 */ 319 public void visitNewClass(JCNewClass tree) { 320 ClassSymbol c = (ClassSymbol)tree.constructor.owner; 321 if (tree.encl == null && 322 c.hasOuterInstance() && 323 outerThisStack.head != null) 324 visitSymbol(outerThisStack.head); 325 super.visitNewClass(tree); 326 } 327 328 /** If tree refers to a qualified this or super expression 329 * for anything but the current class, add the outer this 330 * stack as a free variable. 331 */ 332 public void visitSelect(JCFieldAccess tree) { 333 if ((tree.name == names._this || tree.name == names._super) && 334 tree.selected.type.tsym != clazz && 335 outerThisStack.head != null) 336 visitSymbol(outerThisStack.head); 337 super.visitSelect(tree); 338 } 339 340 /** If tree refers to a superclass constructor call, 341 * add all free variables of the superclass. 342 */ 343 public void visitApply(JCMethodInvocation tree) { 344 if (TreeInfo.name(tree.meth) == names._super) { 345 Symbol constructor = TreeInfo.symbol(tree.meth); 346 ClassSymbol c = (ClassSymbol)constructor.owner; 347 if (c.hasOuterInstance() && 348 !tree.meth.hasTag(SELECT) && 349 outerThisStack.head != null) 350 visitSymbol(outerThisStack.head); 351 } 352 super.visitApply(tree); 353 } 354 } 355 356 ClassSymbol ownerToCopyFreeVarsFrom(ClassSymbol c) { 357 if (!c.isLocal()) { 358 return null; 359 } 360 Symbol currentOwner = c.owner; 361 while ((currentOwner.owner.kind & TYP) != 0 && currentOwner.isLocal()) { 362 currentOwner = currentOwner.owner; 363 } 364 if ((currentOwner.owner.kind & (VAR | MTH)) != 0 && c.isSubClass(currentOwner, types)) { 365 return (ClassSymbol)currentOwner; 366 } 367 return null; 368 } 369 370 /** Return the variables accessed from within a local class, which 371 * are declared in the local class' owner. 372 * (in reverse order of first access). 373 */ 374 List<VarSymbol> freevars(ClassSymbol c) { 375 List<VarSymbol> fvs = freevarCache.get(c); 376 if (fvs != null) { 377 return fvs; 378 } 379 if ((c.owner.kind & (VAR | MTH)) != 0) { 380 FreeVarCollector collector = new FreeVarCollector(c); 381 collector.scan(classDef(c)); 382 fvs = collector.fvs; 383 freevarCache.put(c, fvs); 384 return fvs; 385 } else { 386 ClassSymbol owner = ownerToCopyFreeVarsFrom(c); 387 if (owner != null) { 388 fvs = freevarCache.get(owner); 389 freevarCache.put(c, fvs); 390 return fvs; 391 } else { 392 return List.nil(); 393 } 394 } 395 } 396 397 Map<TypeSymbol,EnumMapping> enumSwitchMap = new LinkedHashMap<>(); 398 399 EnumMapping mapForEnum(DiagnosticPosition pos, TypeSymbol enumClass) { 400 EnumMapping map = enumSwitchMap.get(enumClass); 401 if (map == null) 402 enumSwitchMap.put(enumClass, map = new EnumMapping(pos, enumClass)); 403 return map; 404 } 405 406 /** This map gives a translation table to be used for enum 407 * switches. 408 * 409 * <p>For each enum that appears as the type of a switch 410 * expression, we maintain an EnumMapping to assist in the 411 * translation, as exemplified by the following example: 412 * 413 * <p>we translate 414 * <pre> 415 * switch(colorExpression) { 416 * case red: stmt1; 417 * case green: stmt2; 418 * } 419 * </pre> 420 * into 421 * <pre> 422 * switch(Outer$0.$EnumMap$Color[colorExpression.ordinal()]) { 423 * case 1: stmt1; 424 * case 2: stmt2 425 * } 426 * </pre> 427 * with the auxiliary table initialized as follows: 428 * <pre> 429 * class Outer$0 { 430 * synthetic final int[] $EnumMap$Color = new int[Color.values().length]; 431 * static { 432 * try { $EnumMap$Color[red.ordinal()] = 1; } catch (NoSuchFieldError ex) {} 433 * try { $EnumMap$Color[green.ordinal()] = 2; } catch (NoSuchFieldError ex) {} 434 * } 435 * } 436 * </pre> 437 * class EnumMapping provides mapping data and support methods for this translation. 438 */ 439 class EnumMapping { 440 EnumMapping(DiagnosticPosition pos, TypeSymbol forEnum) { 441 this.forEnum = forEnum; 442 this.values = new LinkedHashMap<>(); 443 this.pos = pos; 444 Name varName = names 445 .fromString(target.syntheticNameChar() + 446 "SwitchMap" + 447 target.syntheticNameChar() + 448 writer.xClassName(forEnum.type).toString() 449 .replace('/', '.') 450 .replace('.', target.syntheticNameChar())); 451 ClassSymbol outerCacheClass = outerCacheClass(); 452 this.mapVar = new VarSymbol(STATIC | SYNTHETIC | FINAL, 453 varName, 454 new ArrayType(syms.intType, syms.arrayClass, 455 Type.noAnnotations), 456 outerCacheClass); 457 enterSynthetic(pos, mapVar, outerCacheClass.members()); 458 } 459 460 DiagnosticPosition pos = null; 461 462 // the next value to use 463 int next = 1; // 0 (unused map elements) go to the default label 464 465 // the enum for which this is a map 466 final TypeSymbol forEnum; 467 468 // the field containing the map 469 final VarSymbol mapVar; 470 471 // the mapped values 472 final Map<VarSymbol,Integer> values; 473 474 JCLiteral forConstant(VarSymbol v) { 475 Integer result = values.get(v); 476 if (result == null) 477 values.put(v, result = next++); 478 return make.Literal(result); 479 } 480 481 // generate the field initializer for the map 482 void translate() { 483 make.at(pos.getStartPosition()); 484 JCClassDecl owner = classDef((ClassSymbol)mapVar.owner); 485 486 // synthetic static final int[] $SwitchMap$Color = new int[Color.values().length]; 487 MethodSymbol valuesMethod = lookupMethod(pos, 488 names.values, 489 forEnum.type, 490 List.<Type>nil()); 491 JCExpression size = make // Color.values().length 492 .Select(make.App(make.QualIdent(valuesMethod)), 493 syms.lengthVar); 494 JCExpression mapVarInit = make 495 .NewArray(make.Type(syms.intType), List.of(size), null) 496 .setType(new ArrayType(syms.intType, syms.arrayClass, 497 Type.noAnnotations)); 498 499 // try { $SwitchMap$Color[red.ordinal()] = 1; } catch (java.lang.NoSuchFieldError ex) {} 500 ListBuffer<JCStatement> stmts = new ListBuffer<>(); 501 Symbol ordinalMethod = lookupMethod(pos, 502 names.ordinal, 503 forEnum.type, 504 List.<Type>nil()); 505 List<JCCatch> catcher = List.<JCCatch>nil() 506 .prepend(make.Catch(make.VarDef(new VarSymbol(PARAMETER, names.ex, 507 syms.noSuchFieldErrorType, 508 syms.noSymbol), 509 null), 510 make.Block(0, List.<JCStatement>nil()))); 511 for (Map.Entry<VarSymbol,Integer> e : values.entrySet()) { 512 VarSymbol enumerator = e.getKey(); 513 Integer mappedValue = e.getValue(); 514 JCExpression assign = make 515 .Assign(make.Indexed(mapVar, 516 make.App(make.Select(make.QualIdent(enumerator), 517 ordinalMethod))), 518 make.Literal(mappedValue)) 519 .setType(syms.intType); 520 JCStatement exec = make.Exec(assign); 521 JCStatement _try = make.Try(make.Block(0, List.of(exec)), catcher, null); 522 stmts.append(_try); 523 } 524 525 owner.defs = owner.defs 526 .prepend(make.Block(STATIC, stmts.toList())) 527 .prepend(make.VarDef(mapVar, mapVarInit)); 528 } 529 } 530 531 532/************************************************************************** 533 * Tree building blocks 534 *************************************************************************/ 535 536 /** Equivalent to make.at(pos.getStartPosition()) with side effect of caching 537 * pos as make_pos, for use in diagnostics. 538 **/ 539 TreeMaker make_at(DiagnosticPosition pos) { 540 make_pos = pos; 541 return make.at(pos); 542 } 543 544 /** Make an attributed tree representing a literal. This will be an 545 * Ident node in the case of boolean literals, a Literal node in all 546 * other cases. 547 * @param type The literal's type. 548 * @param value The literal's value. 549 */ 550 JCExpression makeLit(Type type, Object value) { 551 return make.Literal(type.getTag(), value).setType(type.constType(value)); 552 } 553 554 /** Make an attributed tree representing null. 555 */ 556 JCExpression makeNull() { 557 return makeLit(syms.botType, null); 558 } 559 560 /** Make an attributed class instance creation expression. 561 * @param ctype The class type. 562 * @param args The constructor arguments. 563 */ 564 JCNewClass makeNewClass(Type ctype, List<JCExpression> args) { 565 JCNewClass tree = make.NewClass(null, 566 null, make.QualIdent(ctype.tsym), args, null); 567 tree.constructor = rs.resolveConstructor( 568 make_pos, attrEnv, ctype, TreeInfo.types(args), List.<Type>nil()); 569 tree.type = ctype; 570 return tree; 571 } 572 573 /** Make an attributed unary expression. 574 * @param optag The operators tree tag. 575 * @param arg The operator's argument. 576 */ 577 JCUnary makeUnary(JCTree.Tag optag, JCExpression arg) { 578 JCUnary tree = make.Unary(optag, arg); 579 tree.operator = rs.resolveUnaryOperator( 580 make_pos, optag, attrEnv, arg.type); 581 tree.type = tree.operator.type.getReturnType(); 582 return tree; 583 } 584 585 /** Make an attributed binary expression. 586 * @param optag The operators tree tag. 587 * @param lhs The operator's left argument. 588 * @param rhs The operator's right argument. 589 */ 590 JCBinary makeBinary(JCTree.Tag optag, JCExpression lhs, JCExpression rhs) { 591 JCBinary tree = make.Binary(optag, lhs, rhs); 592 tree.operator = rs.resolveBinaryOperator( 593 make_pos, optag, attrEnv, lhs.type, rhs.type); 594 tree.type = tree.operator.type.getReturnType(); 595 return tree; 596 } 597 598 /** Make an attributed assignop expression. 599 * @param optag The operators tree tag. 600 * @param lhs The operator's left argument. 601 * @param rhs The operator's right argument. 602 */ 603 JCAssignOp makeAssignop(JCTree.Tag optag, JCTree lhs, JCTree rhs) { 604 JCAssignOp tree = make.Assignop(optag, lhs, rhs); 605 tree.operator = rs.resolveBinaryOperator( 606 make_pos, tree.getTag().noAssignOp(), attrEnv, lhs.type, rhs.type); 607 tree.type = lhs.type; 608 return tree; 609 } 610 611 /** Convert tree into string object, unless it has already a 612 * reference type.. 613 */ 614 JCExpression makeString(JCExpression tree) { 615 if (!tree.type.isPrimitiveOrVoid()) { 616 return tree; 617 } else { 618 Symbol valueOfSym = lookupMethod(tree.pos(), 619 names.valueOf, 620 syms.stringType, 621 List.of(tree.type)); 622 return make.App(make.QualIdent(valueOfSym), List.of(tree)); 623 } 624 } 625 626 /** Create an empty anonymous class definition and enter and complete 627 * its symbol. Return the class definition's symbol. 628 * and create 629 * @param flags The class symbol's flags 630 * @param owner The class symbol's owner 631 */ 632 JCClassDecl makeEmptyClass(long flags, ClassSymbol owner) { 633 return makeEmptyClass(flags, owner, null, true); 634 } 635 636 JCClassDecl makeEmptyClass(long flags, ClassSymbol owner, Name flatname, 637 boolean addToDefs) { 638 // Create class symbol. 639 ClassSymbol c = syms.defineClass(names.empty, owner); 640 if (flatname != null) { 641 c.flatname = flatname; 642 } else { 643 c.flatname = chk.localClassName(c); 644 } 645 c.sourcefile = owner.sourcefile; 646 c.completer = null; 647 c.members_field = WriteableScope.create(c); 648 c.flags_field = flags; 649 ClassType ctype = (ClassType) c.type; 650 ctype.supertype_field = syms.objectType; 651 ctype.interfaces_field = List.nil(); 652 653 JCClassDecl odef = classDef(owner); 654 655 // Enter class symbol in owner scope and compiled table. 656 enterSynthetic(odef.pos(), c, owner.members()); 657 chk.compiled.put(c.flatname, c); 658 659 // Create class definition tree. 660 JCClassDecl cdef = make.ClassDef( 661 make.Modifiers(flags), names.empty, 662 List.<JCTypeParameter>nil(), 663 null, List.<JCExpression>nil(), List.<JCTree>nil()); 664 cdef.sym = c; 665 cdef.type = c.type; 666 667 // Append class definition tree to owner's definitions. 668 if (addToDefs) odef.defs = odef.defs.prepend(cdef); 669 return cdef; 670 } 671 672/************************************************************************** 673 * Symbol manipulation utilities 674 *************************************************************************/ 675 676 /** Enter a synthetic symbol in a given scope, but complain if there was already one there. 677 * @param pos Position for error reporting. 678 * @param sym The symbol. 679 * @param s The scope. 680 */ 681 private void enterSynthetic(DiagnosticPosition pos, Symbol sym, WriteableScope s) { 682 s.enter(sym); 683 } 684 685 /** Create a fresh synthetic name within a given scope - the unique name is 686 * obtained by appending '$' chars at the end of the name until no match 687 * is found. 688 * 689 * @param name base name 690 * @param s scope in which the name has to be unique 691 * @return fresh synthetic name 692 */ 693 private Name makeSyntheticName(Name name, Scope s) { 694 do { 695 name = name.append( 696 target.syntheticNameChar(), 697 names.empty); 698 } while (lookupSynthetic(name, s) != null); 699 return name; 700 } 701 702 /** Check whether synthetic symbols generated during lowering conflict 703 * with user-defined symbols. 704 * 705 * @param translatedTrees lowered class trees 706 */ 707 void checkConflicts(List<JCTree> translatedTrees) { 708 for (JCTree t : translatedTrees) { 709 t.accept(conflictsChecker); 710 } 711 } 712 713 JCTree.Visitor conflictsChecker = new TreeScanner() { 714 715 TypeSymbol currentClass; 716 717 @Override 718 public void visitMethodDef(JCMethodDecl that) { 719 chk.checkConflicts(that.pos(), that.sym, currentClass); 720 super.visitMethodDef(that); 721 } 722 723 @Override 724 public void visitVarDef(JCVariableDecl that) { 725 if (that.sym.owner.kind == TYP) { 726 chk.checkConflicts(that.pos(), that.sym, currentClass); 727 } 728 super.visitVarDef(that); 729 } 730 731 @Override 732 public void visitClassDef(JCClassDecl that) { 733 TypeSymbol prevCurrentClass = currentClass; 734 currentClass = that.sym; 735 try { 736 super.visitClassDef(that); 737 } 738 finally { 739 currentClass = prevCurrentClass; 740 } 741 } 742 }; 743 744 /** Look up a synthetic name in a given scope. 745 * @param s The scope. 746 * @param name The name. 747 */ 748 private Symbol lookupSynthetic(Name name, Scope s) { 749 Symbol sym = s.findFirst(name); 750 return (sym==null || (sym.flags()&SYNTHETIC)==0) ? null : sym; 751 } 752 753 /** Look up a method in a given scope. 754 */ 755 private MethodSymbol lookupMethod(DiagnosticPosition pos, Name name, Type qual, List<Type> args) { 756 return rs.resolveInternalMethod(pos, attrEnv, qual, name, args, List.<Type>nil()); 757 } 758 759 /** Look up a constructor. 760 */ 761 private MethodSymbol lookupConstructor(DiagnosticPosition pos, Type qual, List<Type> args) { 762 return rs.resolveInternalConstructor(pos, attrEnv, qual, args, null); 763 } 764 765 /** Look up a field. 766 */ 767 private VarSymbol lookupField(DiagnosticPosition pos, Type qual, Name name) { 768 return rs.resolveInternalField(pos, attrEnv, qual, name); 769 } 770 771 /** Anon inner classes are used as access constructor tags. 772 * accessConstructorTag will use an existing anon class if one is available, 773 * and synthethise a class (with makeEmptyClass) if one is not available. 774 * However, there is a small possibility that an existing class will not 775 * be generated as expected if it is inside a conditional with a constant 776 * expression. If that is found to be the case, create an empty class tree here. 777 */ 778 private void checkAccessConstructorTags() { 779 for (List<ClassSymbol> l = accessConstrTags; l.nonEmpty(); l = l.tail) { 780 ClassSymbol c = l.head; 781 if (isTranslatedClassAvailable(c)) 782 continue; 783 // Create class definition tree. 784 JCClassDecl cdec = makeEmptyClass(STATIC | SYNTHETIC, 785 c.outermostClass(), c.flatname, false); 786 swapAccessConstructorTag(c, cdec.sym); 787 translated.append(cdec); 788 } 789 } 790 // where 791 private boolean isTranslatedClassAvailable(ClassSymbol c) { 792 for (JCTree tree: translated) { 793 if (tree.hasTag(CLASSDEF) 794 && ((JCClassDecl) tree).sym == c) { 795 return true; 796 } 797 } 798 return false; 799 } 800 801 void swapAccessConstructorTag(ClassSymbol oldCTag, ClassSymbol newCTag) { 802 for (MethodSymbol methodSymbol : accessConstrs.values()) { 803 Assert.check(methodSymbol.type.hasTag(METHOD)); 804 MethodType oldMethodType = 805 (MethodType)methodSymbol.type; 806 if (oldMethodType.argtypes.head.tsym == oldCTag) 807 methodSymbol.type = 808 types.createMethodTypeWithParameters(oldMethodType, 809 oldMethodType.getParameterTypes().tail 810 .prepend(newCTag.erasure(types))); 811 } 812 } 813 814/************************************************************************** 815 * Access methods 816 *************************************************************************/ 817 818 /** Access codes for dereferencing, assignment, 819 * and pre/post increment/decrement. 820 * Access codes for assignment operations are determined by method accessCode 821 * below. 822 * 823 * All access codes for accesses to the current class are even. 824 * If a member of the superclass should be accessed instead (because 825 * access was via a qualified super), add one to the corresponding code 826 * for the current class, making the number odd. 827 * This numbering scheme is used by the backend to decide whether 828 * to issue an invokevirtual or invokespecial call. 829 * 830 * @see Gen#visitSelect(JCFieldAccess tree) 831 */ 832 private static final int 833 DEREFcode = 0, 834 ASSIGNcode = 2, 835 PREINCcode = 4, 836 PREDECcode = 6, 837 POSTINCcode = 8, 838 POSTDECcode = 10, 839 FIRSTASGOPcode = 12; 840 841 /** Number of access codes 842 */ 843 private static final int NCODES = accessCode(ByteCodes.lushrl) + 2; 844 845 /** A mapping from symbols to their access numbers. 846 */ 847 private Map<Symbol,Integer> accessNums; 848 849 /** A mapping from symbols to an array of access symbols, indexed by 850 * access code. 851 */ 852 private Map<Symbol,MethodSymbol[]> accessSyms; 853 854 /** A mapping from (constructor) symbols to access constructor symbols. 855 */ 856 private Map<Symbol,MethodSymbol> accessConstrs; 857 858 /** A list of all class symbols used for access constructor tags. 859 */ 860 private List<ClassSymbol> accessConstrTags; 861 862 /** A queue for all accessed symbols. 863 */ 864 private ListBuffer<Symbol> accessed; 865 866 /** Map bytecode of binary operation to access code of corresponding 867 * assignment operation. This is always an even number. 868 */ 869 private static int accessCode(int bytecode) { 870 if (ByteCodes.iadd <= bytecode && bytecode <= ByteCodes.lxor) 871 return (bytecode - iadd) * 2 + FIRSTASGOPcode; 872 else if (bytecode == ByteCodes.string_add) 873 return (ByteCodes.lxor + 1 - iadd) * 2 + FIRSTASGOPcode; 874 else if (ByteCodes.ishll <= bytecode && bytecode <= ByteCodes.lushrl) 875 return (bytecode - ishll + ByteCodes.lxor + 2 - iadd) * 2 + FIRSTASGOPcode; 876 else 877 return -1; 878 } 879 880 /** return access code for identifier, 881 * @param tree The tree representing the identifier use. 882 * @param enclOp The closest enclosing operation node of tree, 883 * null if tree is not a subtree of an operation. 884 */ 885 private static int accessCode(JCTree tree, JCTree enclOp) { 886 if (enclOp == null) 887 return DEREFcode; 888 else if (enclOp.hasTag(ASSIGN) && 889 tree == TreeInfo.skipParens(((JCAssign) enclOp).lhs)) 890 return ASSIGNcode; 891 else if (enclOp.getTag().isIncOrDecUnaryOp() && 892 tree == TreeInfo.skipParens(((JCUnary) enclOp).arg)) 893 return mapTagToUnaryOpCode(enclOp.getTag()); 894 else if (enclOp.getTag().isAssignop() && 895 tree == TreeInfo.skipParens(((JCAssignOp) enclOp).lhs)) 896 return accessCode(((OperatorSymbol) ((JCAssignOp) enclOp).operator).opcode); 897 else 898 return DEREFcode; 899 } 900 901 /** Return binary operator that corresponds to given access code. 902 */ 903 private OperatorSymbol binaryAccessOperator(int acode) { 904 for (Symbol sym : syms.predefClass.members().getSymbols(NON_RECURSIVE)) { 905 if (sym instanceof OperatorSymbol) { 906 OperatorSymbol op = (OperatorSymbol)sym; 907 if (accessCode(op.opcode) == acode) return op; 908 } 909 } 910 return null; 911 } 912 913 /** Return tree tag for assignment operation corresponding 914 * to given binary operator. 915 */ 916 private static JCTree.Tag treeTag(OperatorSymbol operator) { 917 switch (operator.opcode) { 918 case ByteCodes.ior: case ByteCodes.lor: 919 return BITOR_ASG; 920 case ByteCodes.ixor: case ByteCodes.lxor: 921 return BITXOR_ASG; 922 case ByteCodes.iand: case ByteCodes.land: 923 return BITAND_ASG; 924 case ByteCodes.ishl: case ByteCodes.lshl: 925 case ByteCodes.ishll: case ByteCodes.lshll: 926 return SL_ASG; 927 case ByteCodes.ishr: case ByteCodes.lshr: 928 case ByteCodes.ishrl: case ByteCodes.lshrl: 929 return SR_ASG; 930 case ByteCodes.iushr: case ByteCodes.lushr: 931 case ByteCodes.iushrl: case ByteCodes.lushrl: 932 return USR_ASG; 933 case ByteCodes.iadd: case ByteCodes.ladd: 934 case ByteCodes.fadd: case ByteCodes.dadd: 935 case ByteCodes.string_add: 936 return PLUS_ASG; 937 case ByteCodes.isub: case ByteCodes.lsub: 938 case ByteCodes.fsub: case ByteCodes.dsub: 939 return MINUS_ASG; 940 case ByteCodes.imul: case ByteCodes.lmul: 941 case ByteCodes.fmul: case ByteCodes.dmul: 942 return MUL_ASG; 943 case ByteCodes.idiv: case ByteCodes.ldiv: 944 case ByteCodes.fdiv: case ByteCodes.ddiv: 945 return DIV_ASG; 946 case ByteCodes.imod: case ByteCodes.lmod: 947 case ByteCodes.fmod: case ByteCodes.dmod: 948 return MOD_ASG; 949 default: 950 throw new AssertionError(); 951 } 952 } 953 954 /** The name of the access method with number `anum' and access code `acode'. 955 */ 956 Name accessName(int anum, int acode) { 957 return names.fromString( 958 "access" + target.syntheticNameChar() + anum + acode / 10 + acode % 10); 959 } 960 961 /** Return access symbol for a private or protected symbol from an inner class. 962 * @param sym The accessed private symbol. 963 * @param tree The accessing tree. 964 * @param enclOp The closest enclosing operation node of tree, 965 * null if tree is not a subtree of an operation. 966 * @param protAccess Is access to a protected symbol in another 967 * package? 968 * @param refSuper Is access via a (qualified) C.super? 969 */ 970 MethodSymbol accessSymbol(Symbol sym, JCTree tree, JCTree enclOp, 971 boolean protAccess, boolean refSuper) { 972 ClassSymbol accOwner = refSuper && protAccess 973 // For access via qualified super (T.super.x), place the 974 // access symbol on T. 975 ? (ClassSymbol)((JCFieldAccess) tree).selected.type.tsym 976 // Otherwise pretend that the owner of an accessed 977 // protected symbol is the enclosing class of the current 978 // class which is a subclass of the symbol's owner. 979 : accessClass(sym, protAccess, tree); 980 981 Symbol vsym = sym; 982 if (sym.owner != accOwner) { 983 vsym = sym.clone(accOwner); 984 actualSymbols.put(vsym, sym); 985 } 986 987 Integer anum // The access number of the access method. 988 = accessNums.get(vsym); 989 if (anum == null) { 990 anum = accessed.length(); 991 accessNums.put(vsym, anum); 992 accessSyms.put(vsym, new MethodSymbol[NCODES]); 993 accessed.append(vsym); 994 // System.out.println("accessing " + vsym + " in " + vsym.location()); 995 } 996 997 int acode; // The access code of the access method. 998 List<Type> argtypes; // The argument types of the access method. 999 Type restype; // The result type of the access method. 1000 List<Type> thrown; // The thrown exceptions of the access method. 1001 switch (vsym.kind) { 1002 case VAR: 1003 acode = accessCode(tree, enclOp); 1004 if (acode >= FIRSTASGOPcode) { 1005 OperatorSymbol operator = binaryAccessOperator(acode); 1006 if (operator.opcode == string_add) 1007 argtypes = List.of(syms.objectType); 1008 else 1009 argtypes = operator.type.getParameterTypes().tail; 1010 } else if (acode == ASSIGNcode) 1011 argtypes = List.of(vsym.erasure(types)); 1012 else 1013 argtypes = List.nil(); 1014 restype = vsym.erasure(types); 1015 thrown = List.nil(); 1016 break; 1017 case MTH: 1018 acode = DEREFcode; 1019 argtypes = vsym.erasure(types).getParameterTypes(); 1020 restype = vsym.erasure(types).getReturnType(); 1021 thrown = vsym.type.getThrownTypes(); 1022 break; 1023 default: 1024 throw new AssertionError(); 1025 } 1026 1027 // For references via qualified super, increment acode by one, 1028 // making it odd. 1029 if (protAccess && refSuper) acode++; 1030 1031 // Instance access methods get instance as first parameter. 1032 // For protected symbols this needs to be the instance as a member 1033 // of the type containing the accessed symbol, not the class 1034 // containing the access method. 1035 if ((vsym.flags() & STATIC) == 0) { 1036 argtypes = argtypes.prepend(vsym.owner.erasure(types)); 1037 } 1038 MethodSymbol[] accessors = accessSyms.get(vsym); 1039 MethodSymbol accessor = accessors[acode]; 1040 if (accessor == null) { 1041 accessor = new MethodSymbol( 1042 STATIC | SYNTHETIC, 1043 accessName(anum.intValue(), acode), 1044 new MethodType(argtypes, restype, thrown, syms.methodClass), 1045 accOwner); 1046 enterSynthetic(tree.pos(), accessor, accOwner.members()); 1047 accessors[acode] = accessor; 1048 } 1049 return accessor; 1050 } 1051 1052 /** The qualifier to be used for accessing a symbol in an outer class. 1053 * This is either C.sym or C.this.sym, depending on whether or not 1054 * sym is static. 1055 * @param sym The accessed symbol. 1056 */ 1057 JCExpression accessBase(DiagnosticPosition pos, Symbol sym) { 1058 return (sym.flags() & STATIC) != 0 1059 ? access(make.at(pos.getStartPosition()).QualIdent(sym.owner)) 1060 : makeOwnerThis(pos, sym, true); 1061 } 1062 1063 /** Do we need an access method to reference private symbol? 1064 */ 1065 boolean needsPrivateAccess(Symbol sym) { 1066 if ((sym.flags() & PRIVATE) == 0 || sym.owner == currentClass) { 1067 return false; 1068 } else if (sym.name == names.init && sym.owner.isLocal()) { 1069 // private constructor in local class: relax protection 1070 sym.flags_field &= ~PRIVATE; 1071 return false; 1072 } else { 1073 return true; 1074 } 1075 } 1076 1077 /** Do we need an access method to reference symbol in other package? 1078 */ 1079 boolean needsProtectedAccess(Symbol sym, JCTree tree) { 1080 if ((sym.flags() & PROTECTED) == 0 || 1081 sym.owner.owner == currentClass.owner || // fast special case 1082 sym.packge() == currentClass.packge()) 1083 return false; 1084 if (!currentClass.isSubClass(sym.owner, types)) 1085 return true; 1086 if ((sym.flags() & STATIC) != 0 || 1087 !tree.hasTag(SELECT) || 1088 TreeInfo.name(((JCFieldAccess) tree).selected) == names._super) 1089 return false; 1090 return !((JCFieldAccess) tree).selected.type.tsym.isSubClass(currentClass, types); 1091 } 1092 1093 /** The class in which an access method for given symbol goes. 1094 * @param sym The access symbol 1095 * @param protAccess Is access to a protected symbol in another 1096 * package? 1097 */ 1098 ClassSymbol accessClass(Symbol sym, boolean protAccess, JCTree tree) { 1099 if (protAccess) { 1100 Symbol qualifier = null; 1101 ClassSymbol c = currentClass; 1102 if (tree.hasTag(SELECT) && (sym.flags() & STATIC) == 0) { 1103 qualifier = ((JCFieldAccess) tree).selected.type.tsym; 1104 while (!qualifier.isSubClass(c, types)) { 1105 c = c.owner.enclClass(); 1106 } 1107 return c; 1108 } else { 1109 while (!c.isSubClass(sym.owner, types)) { 1110 c = c.owner.enclClass(); 1111 } 1112 } 1113 return c; 1114 } else { 1115 // the symbol is private 1116 return sym.owner.enclClass(); 1117 } 1118 } 1119 1120 private void addPrunedInfo(JCTree tree) { 1121 List<JCTree> infoList = prunedTree.get(currentClass); 1122 infoList = (infoList == null) ? List.of(tree) : infoList.prepend(tree); 1123 prunedTree.put(currentClass, infoList); 1124 } 1125 1126 /** Ensure that identifier is accessible, return tree accessing the identifier. 1127 * @param sym The accessed symbol. 1128 * @param tree The tree referring to the symbol. 1129 * @param enclOp The closest enclosing operation node of tree, 1130 * null if tree is not a subtree of an operation. 1131 * @param refSuper Is access via a (qualified) C.super? 1132 */ 1133 JCExpression access(Symbol sym, JCExpression tree, JCExpression enclOp, boolean refSuper) { 1134 // Access a free variable via its proxy, or its proxy's proxy 1135 while (sym.kind == VAR && sym.owner.kind == MTH && 1136 sym.owner.enclClass() != currentClass) { 1137 // A constant is replaced by its constant value. 1138 Object cv = ((VarSymbol)sym).getConstValue(); 1139 if (cv != null) { 1140 make.at(tree.pos); 1141 return makeLit(sym.type, cv); 1142 } 1143 // Otherwise replace the variable by its proxy. 1144 sym = proxies.findFirst(proxyName(sym.name)); 1145 Assert.check(sym != null && (sym.flags_field & FINAL) != 0); 1146 tree = make.at(tree.pos).Ident(sym); 1147 } 1148 JCExpression base = (tree.hasTag(SELECT)) ? ((JCFieldAccess) tree).selected : null; 1149 switch (sym.kind) { 1150 case TYP: 1151 if (sym.owner.kind != PCK) { 1152 // Convert type idents to 1153 // <flat name> or <package name> . <flat name> 1154 Name flatname = Convert.shortName(sym.flatName()); 1155 while (base != null && 1156 TreeInfo.symbol(base) != null && 1157 TreeInfo.symbol(base).kind != PCK) { 1158 base = (base.hasTag(SELECT)) 1159 ? ((JCFieldAccess) base).selected 1160 : null; 1161 } 1162 if (tree.hasTag(IDENT)) { 1163 ((JCIdent) tree).name = flatname; 1164 } else if (base == null) { 1165 tree = make.at(tree.pos).Ident(sym); 1166 ((JCIdent) tree).name = flatname; 1167 } else { 1168 ((JCFieldAccess) tree).selected = base; 1169 ((JCFieldAccess) tree).name = flatname; 1170 } 1171 } 1172 break; 1173 case MTH: case VAR: 1174 if (sym.owner.kind == TYP) { 1175 1176 // Access methods are required for 1177 // - private members, 1178 // - protected members in a superclass of an 1179 // enclosing class contained in another package. 1180 // - all non-private members accessed via a qualified super. 1181 boolean protAccess = refSuper && !needsPrivateAccess(sym) 1182 || needsProtectedAccess(sym, tree); 1183 boolean accReq = protAccess || needsPrivateAccess(sym); 1184 1185 // A base has to be supplied for 1186 // - simple identifiers accessing variables in outer classes. 1187 boolean baseReq = 1188 base == null && 1189 sym.owner != syms.predefClass && 1190 !sym.isMemberOf(currentClass, types); 1191 1192 if (accReq || baseReq) { 1193 make.at(tree.pos); 1194 1195 // Constants are replaced by their constant value. 1196 if (sym.kind == VAR) { 1197 Object cv = ((VarSymbol)sym).getConstValue(); 1198 if (cv != null) { 1199 addPrunedInfo(tree); 1200 return makeLit(sym.type, cv); 1201 } 1202 } 1203 1204 // Private variables and methods are replaced by calls 1205 // to their access methods. 1206 if (accReq) { 1207 List<JCExpression> args = List.nil(); 1208 if ((sym.flags() & STATIC) == 0) { 1209 // Instance access methods get instance 1210 // as first parameter. 1211 if (base == null) 1212 base = makeOwnerThis(tree.pos(), sym, true); 1213 args = args.prepend(base); 1214 base = null; // so we don't duplicate code 1215 } 1216 Symbol access = accessSymbol(sym, tree, 1217 enclOp, protAccess, 1218 refSuper); 1219 JCExpression receiver = make.Select( 1220 base != null ? base : make.QualIdent(access.owner), 1221 access); 1222 return make.App(receiver, args); 1223 1224 // Other accesses to members of outer classes get a 1225 // qualifier. 1226 } else if (baseReq) { 1227 return make.at(tree.pos).Select( 1228 accessBase(tree.pos(), sym), sym).setType(tree.type); 1229 } 1230 } 1231 } else if (sym.owner.kind == MTH && lambdaTranslationMap != null) { 1232 //sym is a local variable - check the lambda translation map to 1233 //see if sym has been translated to something else in the current 1234 //scope (by LambdaToMethod) 1235 Symbol translatedSym = lambdaTranslationMap.get(sym); 1236 if (translatedSym != null) { 1237 tree = make.at(tree.pos).Ident(translatedSym); 1238 } 1239 } 1240 } 1241 return tree; 1242 } 1243 1244 /** Ensure that identifier is accessible, return tree accessing the identifier. 1245 * @param tree The identifier tree. 1246 */ 1247 JCExpression access(JCExpression tree) { 1248 Symbol sym = TreeInfo.symbol(tree); 1249 return sym == null ? tree : access(sym, tree, null, false); 1250 } 1251 1252 /** Return access constructor for a private constructor, 1253 * or the constructor itself, if no access constructor is needed. 1254 * @param pos The position to report diagnostics, if any. 1255 * @param constr The private constructor. 1256 */ 1257 Symbol accessConstructor(DiagnosticPosition pos, Symbol constr) { 1258 if (needsPrivateAccess(constr)) { 1259 ClassSymbol accOwner = constr.owner.enclClass(); 1260 MethodSymbol aconstr = accessConstrs.get(constr); 1261 if (aconstr == null) { 1262 List<Type> argtypes = constr.type.getParameterTypes(); 1263 if ((accOwner.flags_field & ENUM) != 0) 1264 argtypes = argtypes 1265 .prepend(syms.intType) 1266 .prepend(syms.stringType); 1267 aconstr = new MethodSymbol( 1268 SYNTHETIC, 1269 names.init, 1270 new MethodType( 1271 argtypes.append( 1272 accessConstructorTag().erasure(types)), 1273 constr.type.getReturnType(), 1274 constr.type.getThrownTypes(), 1275 syms.methodClass), 1276 accOwner); 1277 enterSynthetic(pos, aconstr, accOwner.members()); 1278 accessConstrs.put(constr, aconstr); 1279 accessed.append(constr); 1280 } 1281 return aconstr; 1282 } else { 1283 return constr; 1284 } 1285 } 1286 1287 /** Return an anonymous class nested in this toplevel class. 1288 */ 1289 ClassSymbol accessConstructorTag() { 1290 ClassSymbol topClass = currentClass.outermostClass(); 1291 Name flatname = names.fromString("" + topClass.getQualifiedName() + 1292 target.syntheticNameChar() + 1293 "1"); 1294 ClassSymbol ctag = chk.compiled.get(flatname); 1295 if (ctag == null) 1296 ctag = makeEmptyClass(STATIC | SYNTHETIC, topClass).sym; 1297 // keep a record of all tags, to verify that all are generated as required 1298 accessConstrTags = accessConstrTags.prepend(ctag); 1299 return ctag; 1300 } 1301 1302 /** Add all required access methods for a private symbol to enclosing class. 1303 * @param sym The symbol. 1304 */ 1305 void makeAccessible(Symbol sym) { 1306 JCClassDecl cdef = classDef(sym.owner.enclClass()); 1307 if (cdef == null) Assert.error("class def not found: " + sym + " in " + sym.owner); 1308 if (sym.name == names.init) { 1309 cdef.defs = cdef.defs.prepend( 1310 accessConstructorDef(cdef.pos, sym, accessConstrs.get(sym))); 1311 } else { 1312 MethodSymbol[] accessors = accessSyms.get(sym); 1313 for (int i = 0; i < NCODES; i++) { 1314 if (accessors[i] != null) 1315 cdef.defs = cdef.defs.prepend( 1316 accessDef(cdef.pos, sym, accessors[i], i)); 1317 } 1318 } 1319 } 1320 1321 /** Maps unary operator integer codes to JCTree.Tag objects 1322 * @param unaryOpCode the unary operator code 1323 */ 1324 private static Tag mapUnaryOpCodeToTag(int unaryOpCode){ 1325 switch (unaryOpCode){ 1326 case PREINCcode: 1327 return PREINC; 1328 case PREDECcode: 1329 return PREDEC; 1330 case POSTINCcode: 1331 return POSTINC; 1332 case POSTDECcode: 1333 return POSTDEC; 1334 default: 1335 return NO_TAG; 1336 } 1337 } 1338 1339 /** Maps JCTree.Tag objects to unary operator integer codes 1340 * @param tag the JCTree.Tag 1341 */ 1342 private static int mapTagToUnaryOpCode(Tag tag){ 1343 switch (tag){ 1344 case PREINC: 1345 return PREINCcode; 1346 case PREDEC: 1347 return PREDECcode; 1348 case POSTINC: 1349 return POSTINCcode; 1350 case POSTDEC: 1351 return POSTDECcode; 1352 default: 1353 return -1; 1354 } 1355 } 1356 1357 /** Construct definition of an access method. 1358 * @param pos The source code position of the definition. 1359 * @param vsym The private or protected symbol. 1360 * @param accessor The access method for the symbol. 1361 * @param acode The access code. 1362 */ 1363 JCTree accessDef(int pos, Symbol vsym, MethodSymbol accessor, int acode) { 1364// System.err.println("access " + vsym + " with " + accessor);//DEBUG 1365 currentClass = vsym.owner.enclClass(); 1366 make.at(pos); 1367 JCMethodDecl md = make.MethodDef(accessor, null); 1368 1369 // Find actual symbol 1370 Symbol sym = actualSymbols.get(vsym); 1371 if (sym == null) sym = vsym; 1372 1373 JCExpression ref; // The tree referencing the private symbol. 1374 List<JCExpression> args; // Any additional arguments to be passed along. 1375 if ((sym.flags() & STATIC) != 0) { 1376 ref = make.Ident(sym); 1377 args = make.Idents(md.params); 1378 } else { 1379 JCExpression site = make.Ident(md.params.head); 1380 if (acode % 2 != 0) { 1381 //odd access codes represent qualified super accesses - need to 1382 //emit reference to the direct superclass, even if the refered 1383 //member is from an indirect superclass (JLS 13.1) 1384 site.setType(types.erasure(types.supertype(vsym.owner.enclClass().type))); 1385 } 1386 ref = make.Select(site, sym); 1387 args = make.Idents(md.params.tail); 1388 } 1389 JCStatement stat; // The statement accessing the private symbol. 1390 if (sym.kind == VAR) { 1391 // Normalize out all odd access codes by taking floor modulo 2: 1392 int acode1 = acode - (acode & 1); 1393 1394 JCExpression expr; // The access method's return value. 1395 switch (acode1) { 1396 case DEREFcode: 1397 expr = ref; 1398 break; 1399 case ASSIGNcode: 1400 expr = make.Assign(ref, args.head); 1401 break; 1402 case PREINCcode: case POSTINCcode: case PREDECcode: case POSTDECcode: 1403 expr = makeUnary(mapUnaryOpCodeToTag(acode1), ref); 1404 break; 1405 default: 1406 expr = make.Assignop( 1407 treeTag(binaryAccessOperator(acode1)), ref, args.head); 1408 ((JCAssignOp) expr).operator = binaryAccessOperator(acode1); 1409 } 1410 stat = make.Return(expr.setType(sym.type)); 1411 } else { 1412 stat = make.Call(make.App(ref, args)); 1413 } 1414 md.body = make.Block(0, List.of(stat)); 1415 1416 // Make sure all parameters, result types and thrown exceptions 1417 // are accessible. 1418 for (List<JCVariableDecl> l = md.params; l.nonEmpty(); l = l.tail) 1419 l.head.vartype = access(l.head.vartype); 1420 md.restype = access(md.restype); 1421 for (List<JCExpression> l = md.thrown; l.nonEmpty(); l = l.tail) 1422 l.head = access(l.head); 1423 1424 return md; 1425 } 1426 1427 /** Construct definition of an access constructor. 1428 * @param pos The source code position of the definition. 1429 * @param constr The private constructor. 1430 * @param accessor The access method for the constructor. 1431 */ 1432 JCTree accessConstructorDef(int pos, Symbol constr, MethodSymbol accessor) { 1433 make.at(pos); 1434 JCMethodDecl md = make.MethodDef(accessor, 1435 accessor.externalType(types), 1436 null); 1437 JCIdent callee = make.Ident(names._this); 1438 callee.sym = constr; 1439 callee.type = constr.type; 1440 md.body = 1441 make.Block(0, List.<JCStatement>of( 1442 make.Call( 1443 make.App( 1444 callee, 1445 make.Idents(md.params.reverse().tail.reverse()))))); 1446 return md; 1447 } 1448 1449/************************************************************************** 1450 * Free variables proxies and this$n 1451 *************************************************************************/ 1452 1453 /** A scope containing all free variable proxies for currently translated 1454 * class, as well as its this$n symbol (if needed). 1455 * Proxy scopes are nested in the same way classes are. 1456 * Inside a constructor, proxies and any this$n symbol are duplicated 1457 * in an additional innermost scope, where they represent the constructor 1458 * parameters. 1459 */ 1460 WriteableScope proxies; 1461 1462 /** A scope containing all unnamed resource variables/saved 1463 * exception variables for translated TWR blocks 1464 */ 1465 WriteableScope twrVars; 1466 1467 /** A stack containing the this$n field of the currently translated 1468 * classes (if needed) in innermost first order. 1469 * Inside a constructor, proxies and any this$n symbol are duplicated 1470 * in an additional innermost scope, where they represent the constructor 1471 * parameters. 1472 */ 1473 List<VarSymbol> outerThisStack; 1474 1475 /** The name of a free variable proxy. 1476 */ 1477 Name proxyName(Name name) { 1478 return names.fromString("val" + target.syntheticNameChar() + name); 1479 } 1480 1481 /** Proxy definitions for all free variables in given list, in reverse order. 1482 * @param pos The source code position of the definition. 1483 * @param freevars The free variables. 1484 * @param owner The class in which the definitions go. 1485 */ 1486 List<JCVariableDecl> freevarDefs(int pos, List<VarSymbol> freevars, Symbol owner) { 1487 return freevarDefs(pos, freevars, owner, 0); 1488 } 1489 1490 List<JCVariableDecl> freevarDefs(int pos, List<VarSymbol> freevars, Symbol owner, 1491 long additionalFlags) { 1492 long flags = FINAL | SYNTHETIC | additionalFlags; 1493 List<JCVariableDecl> defs = List.nil(); 1494 for (List<VarSymbol> l = freevars; l.nonEmpty(); l = l.tail) { 1495 VarSymbol v = l.head; 1496 VarSymbol proxy = new VarSymbol( 1497 flags, proxyName(v.name), v.erasure(types), owner); 1498 proxies.enter(proxy); 1499 JCVariableDecl vd = make.at(pos).VarDef(proxy, null); 1500 vd.vartype = access(vd.vartype); 1501 defs = defs.prepend(vd); 1502 } 1503 return defs; 1504 } 1505 1506 /** The name of a this$n field 1507 * @param type The class referenced by the this$n field 1508 */ 1509 Name outerThisName(Type type, Symbol owner) { 1510 Type t = type.getEnclosingType(); 1511 int nestingLevel = 0; 1512 while (t.hasTag(CLASS)) { 1513 t = t.getEnclosingType(); 1514 nestingLevel++; 1515 } 1516 Name result = names.fromString("this" + target.syntheticNameChar() + nestingLevel); 1517 while (owner.kind == TYP && ((ClassSymbol)owner).members().findFirst(result) != null) 1518 result = names.fromString(result.toString() + target.syntheticNameChar()); 1519 return result; 1520 } 1521 1522 private VarSymbol makeOuterThisVarSymbol(Symbol owner, long flags) { 1523 Type target = types.erasure(owner.enclClass().type.getEnclosingType()); 1524 VarSymbol outerThis = 1525 new VarSymbol(flags, outerThisName(target, owner), target, owner); 1526 outerThisStack = outerThisStack.prepend(outerThis); 1527 return outerThis; 1528 } 1529 1530 private JCVariableDecl makeOuterThisVarDecl(int pos, VarSymbol sym) { 1531 JCVariableDecl vd = make.at(pos).VarDef(sym, null); 1532 vd.vartype = access(vd.vartype); 1533 return vd; 1534 } 1535 1536 /** Definition for this$n field. 1537 * @param pos The source code position of the definition. 1538 * @param owner The method in which the definition goes. 1539 */ 1540 JCVariableDecl outerThisDef(int pos, MethodSymbol owner) { 1541 ClassSymbol c = owner.enclClass(); 1542 boolean isMandated = 1543 // Anonymous constructors 1544 (owner.isConstructor() && owner.isAnonymous()) || 1545 // Constructors of non-private inner member classes 1546 (owner.isConstructor() && c.isInner() && 1547 !c.isPrivate() && !c.isStatic()); 1548 long flags = 1549 FINAL | (isMandated ? MANDATED : SYNTHETIC) | PARAMETER; 1550 VarSymbol outerThis = makeOuterThisVarSymbol(owner, flags); 1551 owner.extraParams = owner.extraParams.prepend(outerThis); 1552 return makeOuterThisVarDecl(pos, outerThis); 1553 } 1554 1555 /** Definition for this$n field. 1556 * @param pos The source code position of the definition. 1557 * @param owner The class in which the definition goes. 1558 */ 1559 JCVariableDecl outerThisDef(int pos, ClassSymbol owner) { 1560 VarSymbol outerThis = makeOuterThisVarSymbol(owner, FINAL | SYNTHETIC); 1561 return makeOuterThisVarDecl(pos, outerThis); 1562 } 1563 1564 /** Return a list of trees that load the free variables in given list, 1565 * in reverse order. 1566 * @param pos The source code position to be used for the trees. 1567 * @param freevars The list of free variables. 1568 */ 1569 List<JCExpression> loadFreevars(DiagnosticPosition pos, List<VarSymbol> freevars) { 1570 List<JCExpression> args = List.nil(); 1571 for (List<VarSymbol> l = freevars; l.nonEmpty(); l = l.tail) 1572 args = args.prepend(loadFreevar(pos, l.head)); 1573 return args; 1574 } 1575//where 1576 JCExpression loadFreevar(DiagnosticPosition pos, VarSymbol v) { 1577 return access(v, make.at(pos).Ident(v), null, false); 1578 } 1579 1580 /** Construct a tree simulating the expression {@code C.this}. 1581 * @param pos The source code position to be used for the tree. 1582 * @param c The qualifier class. 1583 */ 1584 JCExpression makeThis(DiagnosticPosition pos, TypeSymbol c) { 1585 if (currentClass == c) { 1586 // in this case, `this' works fine 1587 return make.at(pos).This(c.erasure(types)); 1588 } else { 1589 // need to go via this$n 1590 return makeOuterThis(pos, c); 1591 } 1592 } 1593 1594 /** 1595 * Optionally replace a try statement with the desugaring of a 1596 * try-with-resources statement. The canonical desugaring of 1597 * 1598 * try ResourceSpecification 1599 * Block 1600 * 1601 * is 1602 * 1603 * { 1604 * final VariableModifiers_minus_final R #resource = Expression; 1605 * Throwable #primaryException = null; 1606 * 1607 * try ResourceSpecificationtail 1608 * Block 1609 * catch (Throwable #t) { 1610 * #primaryException = t; 1611 * throw #t; 1612 * } finally { 1613 * if (#resource != null) { 1614 * if (#primaryException != null) { 1615 * try { 1616 * #resource.close(); 1617 * } catch(Throwable #suppressedException) { 1618 * #primaryException.addSuppressed(#suppressedException); 1619 * } 1620 * } else { 1621 * #resource.close(); 1622 * } 1623 * } 1624 * } 1625 * 1626 * @param tree The try statement to inspect. 1627 * @return A a desugared try-with-resources tree, or the original 1628 * try block if there are no resources to manage. 1629 */ 1630 JCTree makeTwrTry(JCTry tree) { 1631 make_at(tree.pos()); 1632 twrVars = twrVars.dup(); 1633 JCBlock twrBlock = makeTwrBlock(tree.resources, tree.body, 1634 tree.finallyCanCompleteNormally, 0); 1635 if (tree.catchers.isEmpty() && tree.finalizer == null) 1636 result = translate(twrBlock); 1637 else 1638 result = translate(make.Try(twrBlock, tree.catchers, tree.finalizer)); 1639 twrVars = twrVars.leave(); 1640 return result; 1641 } 1642 1643 private JCBlock makeTwrBlock(List<JCTree> resources, JCBlock block, 1644 boolean finallyCanCompleteNormally, int depth) { 1645 if (resources.isEmpty()) 1646 return block; 1647 1648 // Add resource declaration or expression to block statements 1649 ListBuffer<JCStatement> stats = new ListBuffer<>(); 1650 JCTree resource = resources.head; 1651 JCExpression expr = null; 1652 if (resource instanceof JCVariableDecl) { 1653 JCVariableDecl var = (JCVariableDecl) resource; 1654 expr = make.Ident(var.sym).setType(resource.type); 1655 stats.add(var); 1656 } else { 1657 Assert.check(resource instanceof JCExpression); 1658 VarSymbol syntheticTwrVar = 1659 new VarSymbol(SYNTHETIC | FINAL, 1660 makeSyntheticName(names.fromString("twrVar" + 1661 depth), twrVars), 1662 (resource.type.hasTag(BOT)) ? 1663 syms.autoCloseableType : resource.type, 1664 currentMethodSym); 1665 twrVars.enter(syntheticTwrVar); 1666 JCVariableDecl syntheticTwrVarDecl = 1667 make.VarDef(syntheticTwrVar, (JCExpression)resource); 1668 expr = (JCExpression)make.Ident(syntheticTwrVar); 1669 stats.add(syntheticTwrVarDecl); 1670 } 1671 1672 // Add primaryException declaration 1673 VarSymbol primaryException = 1674 new VarSymbol(SYNTHETIC, 1675 makeSyntheticName(names.fromString("primaryException" + 1676 depth), twrVars), 1677 syms.throwableType, 1678 currentMethodSym); 1679 twrVars.enter(primaryException); 1680 JCVariableDecl primaryExceptionTreeDecl = make.VarDef(primaryException, makeNull()); 1681 stats.add(primaryExceptionTreeDecl); 1682 1683 // Create catch clause that saves exception and then rethrows it 1684 VarSymbol param = 1685 new VarSymbol(FINAL|SYNTHETIC, 1686 names.fromString("t" + 1687 target.syntheticNameChar()), 1688 syms.throwableType, 1689 currentMethodSym); 1690 JCVariableDecl paramTree = make.VarDef(param, null); 1691 JCStatement assign = make.Assignment(primaryException, make.Ident(param)); 1692 JCStatement rethrowStat = make.Throw(make.Ident(param)); 1693 JCBlock catchBlock = make.Block(0L, List.<JCStatement>of(assign, rethrowStat)); 1694 JCCatch catchClause = make.Catch(paramTree, catchBlock); 1695 1696 int oldPos = make.pos; 1697 make.at(TreeInfo.endPos(block)); 1698 JCBlock finallyClause = makeTwrFinallyClause(primaryException, expr); 1699 make.at(oldPos); 1700 JCTry outerTry = make.Try(makeTwrBlock(resources.tail, block, 1701 finallyCanCompleteNormally, depth + 1), 1702 List.<JCCatch>of(catchClause), 1703 finallyClause); 1704 outerTry.finallyCanCompleteNormally = finallyCanCompleteNormally; 1705 stats.add(outerTry); 1706 JCBlock newBlock = make.Block(0L, stats.toList()); 1707 return newBlock; 1708 } 1709 1710 private JCBlock makeTwrFinallyClause(Symbol primaryException, JCExpression resource) { 1711 // primaryException.addSuppressed(catchException); 1712 VarSymbol catchException = 1713 new VarSymbol(SYNTHETIC, make.paramName(2), 1714 syms.throwableType, 1715 currentMethodSym); 1716 JCStatement addSuppressionStatement = 1717 make.Exec(makeCall(make.Ident(primaryException), 1718 names.addSuppressed, 1719 List.<JCExpression>of(make.Ident(catchException)))); 1720 1721 // try { resource.close(); } catch (e) { primaryException.addSuppressed(e); } 1722 JCBlock tryBlock = 1723 make.Block(0L, List.<JCStatement>of(makeResourceCloseInvocation(resource))); 1724 JCVariableDecl catchExceptionDecl = make.VarDef(catchException, null); 1725 JCBlock catchBlock = make.Block(0L, List.<JCStatement>of(addSuppressionStatement)); 1726 List<JCCatch> catchClauses = List.<JCCatch>of(make.Catch(catchExceptionDecl, catchBlock)); 1727 JCTry tryTree = make.Try(tryBlock, catchClauses, null); 1728 tryTree.finallyCanCompleteNormally = true; 1729 1730 // if (primaryException != null) {try...} else resourceClose; 1731 JCIf closeIfStatement = make.If(makeNonNullCheck(make.Ident(primaryException)), 1732 tryTree, 1733 makeResourceCloseInvocation(resource)); 1734 1735 // if (#resource != null) { if (primaryException ... } 1736 return make.Block(0L, 1737 List.<JCStatement>of(make.If(makeNonNullCheck(resource), 1738 closeIfStatement, 1739 null))); 1740 } 1741 1742 private JCStatement makeResourceCloseInvocation(JCExpression resource) { 1743 // convert to AutoCloseable if needed 1744 if (types.asSuper(resource.type, syms.autoCloseableType.tsym) == null) { 1745 resource = (JCExpression) convert(resource, syms.autoCloseableType); 1746 } 1747 1748 // create resource.close() method invocation 1749 JCExpression resourceClose = makeCall(resource, 1750 names.close, 1751 List.<JCExpression>nil()); 1752 return make.Exec(resourceClose); 1753 } 1754 1755 private JCExpression makeNonNullCheck(JCExpression expression) { 1756 return makeBinary(NE, expression, makeNull()); 1757 } 1758 1759 /** Construct a tree that represents the outer instance 1760 * {@code C.this}. Never pick the current `this'. 1761 * @param pos The source code position to be used for the tree. 1762 * @param c The qualifier class. 1763 */ 1764 JCExpression makeOuterThis(DiagnosticPosition pos, TypeSymbol c) { 1765 List<VarSymbol> ots = outerThisStack; 1766 if (ots.isEmpty()) { 1767 log.error(pos, "no.encl.instance.of.type.in.scope", c); 1768 Assert.error(); 1769 return makeNull(); 1770 } 1771 VarSymbol ot = ots.head; 1772 JCExpression tree = access(make.at(pos).Ident(ot)); 1773 TypeSymbol otc = ot.type.tsym; 1774 while (otc != c) { 1775 do { 1776 ots = ots.tail; 1777 if (ots.isEmpty()) { 1778 log.error(pos, 1779 "no.encl.instance.of.type.in.scope", 1780 c); 1781 Assert.error(); // should have been caught in Attr 1782 return tree; 1783 } 1784 ot = ots.head; 1785 } while (ot.owner != otc); 1786 if (otc.owner.kind != PCK && !otc.hasOuterInstance()) { 1787 chk.earlyRefError(pos, c); 1788 Assert.error(); // should have been caught in Attr 1789 return makeNull(); 1790 } 1791 tree = access(make.at(pos).Select(tree, ot)); 1792 otc = ot.type.tsym; 1793 } 1794 return tree; 1795 } 1796 1797 /** Construct a tree that represents the closest outer instance 1798 * {@code C.this} such that the given symbol is a member of C. 1799 * @param pos The source code position to be used for the tree. 1800 * @param sym The accessed symbol. 1801 * @param preciseMatch should we accept a type that is a subtype of 1802 * sym's owner, even if it doesn't contain sym 1803 * due to hiding, overriding, or non-inheritance 1804 * due to protection? 1805 */ 1806 JCExpression makeOwnerThis(DiagnosticPosition pos, Symbol sym, boolean preciseMatch) { 1807 Symbol c = sym.owner; 1808 if (preciseMatch ? sym.isMemberOf(currentClass, types) 1809 : currentClass.isSubClass(sym.owner, types)) { 1810 // in this case, `this' works fine 1811 return make.at(pos).This(c.erasure(types)); 1812 } else { 1813 // need to go via this$n 1814 return makeOwnerThisN(pos, sym, preciseMatch); 1815 } 1816 } 1817 1818 /** 1819 * Similar to makeOwnerThis but will never pick "this". 1820 */ 1821 JCExpression makeOwnerThisN(DiagnosticPosition pos, Symbol sym, boolean preciseMatch) { 1822 Symbol c = sym.owner; 1823 List<VarSymbol> ots = outerThisStack; 1824 if (ots.isEmpty()) { 1825 log.error(pos, "no.encl.instance.of.type.in.scope", c); 1826 Assert.error(); 1827 return makeNull(); 1828 } 1829 VarSymbol ot = ots.head; 1830 JCExpression tree = access(make.at(pos).Ident(ot)); 1831 TypeSymbol otc = ot.type.tsym; 1832 while (!(preciseMatch ? sym.isMemberOf(otc, types) : otc.isSubClass(sym.owner, types))) { 1833 do { 1834 ots = ots.tail; 1835 if (ots.isEmpty()) { 1836 log.error(pos, 1837 "no.encl.instance.of.type.in.scope", 1838 c); 1839 Assert.error(); 1840 return tree; 1841 } 1842 ot = ots.head; 1843 } while (ot.owner != otc); 1844 tree = access(make.at(pos).Select(tree, ot)); 1845 otc = ot.type.tsym; 1846 } 1847 return tree; 1848 } 1849 1850 /** Return tree simulating the assignment {@code this.name = name}, where 1851 * name is the name of a free variable. 1852 */ 1853 JCStatement initField(int pos, Name name) { 1854 Iterator<Symbol> it = proxies.getSymbolsByName(name).iterator(); 1855 Symbol rhs = it.next(); 1856 Assert.check(rhs.owner.kind == MTH); 1857 Symbol lhs = it.next(); 1858 Assert.check(rhs.owner.owner == lhs.owner); 1859 make.at(pos); 1860 return 1861 make.Exec( 1862 make.Assign( 1863 make.Select(make.This(lhs.owner.erasure(types)), lhs), 1864 make.Ident(rhs)).setType(lhs.erasure(types))); 1865 } 1866 1867 /** Return tree simulating the assignment {@code this.this$n = this$n}. 1868 */ 1869 JCStatement initOuterThis(int pos) { 1870 VarSymbol rhs = outerThisStack.head; 1871 Assert.check(rhs.owner.kind == MTH); 1872 VarSymbol lhs = outerThisStack.tail.head; 1873 Assert.check(rhs.owner.owner == lhs.owner); 1874 make.at(pos); 1875 return 1876 make.Exec( 1877 make.Assign( 1878 make.Select(make.This(lhs.owner.erasure(types)), lhs), 1879 make.Ident(rhs)).setType(lhs.erasure(types))); 1880 } 1881 1882/************************************************************************** 1883 * Code for .class 1884 *************************************************************************/ 1885 1886 /** Return the symbol of a class to contain a cache of 1887 * compiler-generated statics such as class$ and the 1888 * $assertionsDisabled flag. We create an anonymous nested class 1889 * (unless one already exists) and return its symbol. However, 1890 * for backward compatibility in 1.4 and earlier we use the 1891 * top-level class itself. 1892 */ 1893 private ClassSymbol outerCacheClass() { 1894 ClassSymbol clazz = outermostClassDef.sym; 1895 Scope s = clazz.members(); 1896 for (Symbol sym : s.getSymbols(NON_RECURSIVE)) 1897 if (sym.kind == TYP && 1898 sym.name == names.empty && 1899 (sym.flags() & INTERFACE) == 0) return (ClassSymbol) sym; 1900 return makeEmptyClass(STATIC | SYNTHETIC, clazz).sym; 1901 } 1902 1903 /** Return symbol for "class$" method. If there is no method definition 1904 * for class$, construct one as follows: 1905 * 1906 * class class$(String x0) { 1907 * try { 1908 * return Class.forName(x0); 1909 * } catch (ClassNotFoundException x1) { 1910 * throw new NoClassDefFoundError(x1.getMessage()); 1911 * } 1912 * } 1913 */ 1914 private MethodSymbol classDollarSym(DiagnosticPosition pos) { 1915 ClassSymbol outerCacheClass = outerCacheClass(); 1916 MethodSymbol classDollarSym = 1917 (MethodSymbol)lookupSynthetic(classDollar, 1918 outerCacheClass.members()); 1919 if (classDollarSym == null) { 1920 classDollarSym = new MethodSymbol( 1921 STATIC | SYNTHETIC, 1922 classDollar, 1923 new MethodType( 1924 List.of(syms.stringType), 1925 types.erasure(syms.classType), 1926 List.<Type>nil(), 1927 syms.methodClass), 1928 outerCacheClass); 1929 enterSynthetic(pos, classDollarSym, outerCacheClass.members()); 1930 1931 JCMethodDecl md = make.MethodDef(classDollarSym, null); 1932 try { 1933 md.body = classDollarSymBody(pos, md); 1934 } catch (CompletionFailure ex) { 1935 md.body = make.Block(0, List.<JCStatement>nil()); 1936 chk.completionError(pos, ex); 1937 } 1938 JCClassDecl outerCacheClassDef = classDef(outerCacheClass); 1939 outerCacheClassDef.defs = outerCacheClassDef.defs.prepend(md); 1940 } 1941 return classDollarSym; 1942 } 1943 1944 /** Generate code for class$(String name). */ 1945 JCBlock classDollarSymBody(DiagnosticPosition pos, JCMethodDecl md) { 1946 MethodSymbol classDollarSym = md.sym; 1947 ClassSymbol outerCacheClass = (ClassSymbol)classDollarSym.owner; 1948 1949 JCBlock returnResult; 1950 1951 // cache the current loader in cl$ 1952 // clsym = "private static ClassLoader cl$" 1953 VarSymbol clsym = new VarSymbol(STATIC | SYNTHETIC, 1954 names.fromString("cl" + target.syntheticNameChar()), 1955 syms.classLoaderType, 1956 outerCacheClass); 1957 enterSynthetic(pos, clsym, outerCacheClass.members()); 1958 1959 // emit "private static ClassLoader cl$;" 1960 JCVariableDecl cldef = make.VarDef(clsym, null); 1961 JCClassDecl outerCacheClassDef = classDef(outerCacheClass); 1962 outerCacheClassDef.defs = outerCacheClassDef.defs.prepend(cldef); 1963 1964 // newcache := "new cache$1[0]" 1965 JCNewArray newcache = make.NewArray(make.Type(outerCacheClass.type), 1966 List.<JCExpression>of(make.Literal(INT, 0).setType(syms.intType)), 1967 null); 1968 newcache.type = new ArrayType(types.erasure(outerCacheClass.type), 1969 syms.arrayClass, Type.noAnnotations); 1970 1971 // forNameSym := java.lang.Class.forName( 1972 // String s,boolean init,ClassLoader loader) 1973 Symbol forNameSym = lookupMethod(make_pos, names.forName, 1974 types.erasure(syms.classType), 1975 List.of(syms.stringType, 1976 syms.booleanType, 1977 syms.classLoaderType)); 1978 // clvalue := "(cl$ == null) ? 1979 // $newcache.getClass().getComponentType().getClassLoader() : cl$" 1980 JCExpression clvalue = 1981 make.Conditional( 1982 makeBinary(EQ, make.Ident(clsym), makeNull()), 1983 make.Assign(make.Ident(clsym), 1984 makeCall( 1985 makeCall(makeCall(newcache, 1986 names.getClass, 1987 List.<JCExpression>nil()), 1988 names.getComponentType, 1989 List.<JCExpression>nil()), 1990 names.getClassLoader, 1991 List.<JCExpression>nil())).setType(syms.classLoaderType), 1992 make.Ident(clsym)).setType(syms.classLoaderType); 1993 1994 // returnResult := "{ return Class.forName(param1, false, cl$); }" 1995 List<JCExpression> args = List.of(make.Ident(md.params.head.sym), 1996 makeLit(syms.booleanType, 0), 1997 clvalue); 1998 returnResult = make.Block(0, List.<JCStatement>of(make.Call(make.App(make.Ident(forNameSym), args)))); 1999 2000 // catchParam := ClassNotFoundException e1 2001 VarSymbol catchParam = 2002 new VarSymbol(SYNTHETIC, make.paramName(1), 2003 syms.classNotFoundExceptionType, 2004 classDollarSym); 2005 2006 JCStatement rethrow; 2007 // rethrow = "throw new NoClassDefFoundError().initCause(e); 2008 JCExpression throwExpr = 2009 makeCall(makeNewClass(syms.noClassDefFoundErrorType, 2010 List.<JCExpression>nil()), 2011 names.initCause, 2012 List.<JCExpression>of(make.Ident(catchParam))); 2013 rethrow = make.Throw(throwExpr); 2014 2015 // rethrowStmt := "( $rethrow )" 2016 JCBlock rethrowStmt = make.Block(0, List.of(rethrow)); 2017 2018 // catchBlock := "catch ($catchParam) $rethrowStmt" 2019 JCCatch catchBlock = make.Catch(make.VarDef(catchParam, null), 2020 rethrowStmt); 2021 2022 // tryCatch := "try $returnResult $catchBlock" 2023 JCStatement tryCatch = make.Try(returnResult, 2024 List.of(catchBlock), null); 2025 2026 return make.Block(0, List.of(tryCatch)); 2027 } 2028 // where 2029 /** Create an attributed tree of the form left.name(). */ 2030 private JCMethodInvocation makeCall(JCExpression left, Name name, List<JCExpression> args) { 2031 Assert.checkNonNull(left.type); 2032 Symbol funcsym = lookupMethod(make_pos, name, left.type, 2033 TreeInfo.types(args)); 2034 return make.App(make.Select(left, funcsym), args); 2035 } 2036 2037 /** The Name Of The variable to cache T.class values. 2038 * @param sig The signature of type T. 2039 */ 2040 private Name cacheName(String sig) { 2041 StringBuilder buf = new StringBuilder(); 2042 if (sig.startsWith("[")) { 2043 buf = buf.append("array"); 2044 while (sig.startsWith("[")) { 2045 buf = buf.append(target.syntheticNameChar()); 2046 sig = sig.substring(1); 2047 } 2048 if (sig.startsWith("L")) { 2049 sig = sig.substring(0, sig.length() - 1); 2050 } 2051 } else { 2052 buf = buf.append("class" + target.syntheticNameChar()); 2053 } 2054 buf = buf.append(sig.replace('.', target.syntheticNameChar())); 2055 return names.fromString(buf.toString()); 2056 } 2057 2058 /** The variable symbol that caches T.class values. 2059 * If none exists yet, create a definition. 2060 * @param sig The signature of type T. 2061 * @param pos The position to report diagnostics, if any. 2062 */ 2063 private VarSymbol cacheSym(DiagnosticPosition pos, String sig) { 2064 ClassSymbol outerCacheClass = outerCacheClass(); 2065 Name cname = cacheName(sig); 2066 VarSymbol cacheSym = 2067 (VarSymbol)lookupSynthetic(cname, outerCacheClass.members()); 2068 if (cacheSym == null) { 2069 cacheSym = new VarSymbol( 2070 STATIC | SYNTHETIC, cname, types.erasure(syms.classType), outerCacheClass); 2071 enterSynthetic(pos, cacheSym, outerCacheClass.members()); 2072 2073 JCVariableDecl cacheDef = make.VarDef(cacheSym, null); 2074 JCClassDecl outerCacheClassDef = classDef(outerCacheClass); 2075 outerCacheClassDef.defs = outerCacheClassDef.defs.prepend(cacheDef); 2076 } 2077 return cacheSym; 2078 } 2079 2080 /** The tree simulating a T.class expression. 2081 * @param clazz The tree identifying type T. 2082 */ 2083 private JCExpression classOf(JCTree clazz) { 2084 return classOfType(clazz.type, clazz.pos()); 2085 } 2086 2087 private JCExpression classOfType(Type type, DiagnosticPosition pos) { 2088 switch (type.getTag()) { 2089 case BYTE: case SHORT: case CHAR: case INT: case LONG: case FLOAT: 2090 case DOUBLE: case BOOLEAN: case VOID: 2091 // replace with <BoxedClass>.TYPE 2092 ClassSymbol c = types.boxedClass(type); 2093 Symbol typeSym = 2094 rs.accessBase( 2095 rs.findIdentInType(attrEnv, c.type, names.TYPE, VAR), 2096 pos, c.type, names.TYPE, true); 2097 if (typeSym.kind == VAR) 2098 ((VarSymbol)typeSym).getConstValue(); // ensure initializer is evaluated 2099 return make.QualIdent(typeSym); 2100 case CLASS: case ARRAY: 2101 VarSymbol sym = new VarSymbol( 2102 STATIC | PUBLIC | FINAL, names._class, 2103 syms.classType, type.tsym); 2104 return make_at(pos).Select(make.Type(type), sym); 2105 default: 2106 throw new AssertionError(); 2107 } 2108 } 2109 2110/************************************************************************** 2111 * Code for enabling/disabling assertions. 2112 *************************************************************************/ 2113 2114 private ClassSymbol assertionsDisabledClassCache; 2115 2116 /**Used to create an auxiliary class to hold $assertionsDisabled for interfaces. 2117 */ 2118 private ClassSymbol assertionsDisabledClass() { 2119 if (assertionsDisabledClassCache != null) return assertionsDisabledClassCache; 2120 2121 assertionsDisabledClassCache = makeEmptyClass(STATIC | SYNTHETIC, outermostClassDef.sym).sym; 2122 2123 return assertionsDisabledClassCache; 2124 } 2125 2126 // This code is not particularly robust if the user has 2127 // previously declared a member named '$assertionsDisabled'. 2128 // The same faulty idiom also appears in the translation of 2129 // class literals above. We should report an error if a 2130 // previous declaration is not synthetic. 2131 2132 private JCExpression assertFlagTest(DiagnosticPosition pos) { 2133 // Outermost class may be either true class or an interface. 2134 ClassSymbol outermostClass = outermostClassDef.sym; 2135 2136 //only classes can hold a non-public field, look for a usable one: 2137 ClassSymbol container = !currentClass.isInterface() ? currentClass : 2138 assertionsDisabledClass(); 2139 2140 VarSymbol assertDisabledSym = 2141 (VarSymbol)lookupSynthetic(dollarAssertionsDisabled, 2142 container.members()); 2143 if (assertDisabledSym == null) { 2144 assertDisabledSym = 2145 new VarSymbol(STATIC | FINAL | SYNTHETIC, 2146 dollarAssertionsDisabled, 2147 syms.booleanType, 2148 container); 2149 enterSynthetic(pos, assertDisabledSym, container.members()); 2150 Symbol desiredAssertionStatusSym = lookupMethod(pos, 2151 names.desiredAssertionStatus, 2152 types.erasure(syms.classType), 2153 List.<Type>nil()); 2154 JCClassDecl containerDef = classDef(container); 2155 make_at(containerDef.pos()); 2156 JCExpression notStatus = makeUnary(NOT, make.App(make.Select( 2157 classOfType(types.erasure(outermostClass.type), 2158 containerDef.pos()), 2159 desiredAssertionStatusSym))); 2160 JCVariableDecl assertDisabledDef = make.VarDef(assertDisabledSym, 2161 notStatus); 2162 containerDef.defs = containerDef.defs.prepend(assertDisabledDef); 2163 2164 if (currentClass.isInterface()) { 2165 //need to load the assertions enabled/disabled state while 2166 //initializing the interface: 2167 JCClassDecl currentClassDef = classDef(currentClass); 2168 make_at(currentClassDef.pos()); 2169 JCStatement dummy = make.If(make.QualIdent(assertDisabledSym), make.Skip(), null); 2170 JCBlock clinit = make.Block(STATIC, List.<JCStatement>of(dummy)); 2171 currentClassDef.defs = currentClassDef.defs.prepend(clinit); 2172 } 2173 } 2174 make_at(pos); 2175 return makeUnary(NOT, make.Ident(assertDisabledSym)); 2176 } 2177 2178 2179/************************************************************************** 2180 * Building blocks for let expressions 2181 *************************************************************************/ 2182 2183 interface TreeBuilder { 2184 JCTree build(JCTree arg); 2185 } 2186 2187 /** Construct an expression using the builder, with the given rval 2188 * expression as an argument to the builder. However, the rval 2189 * expression must be computed only once, even if used multiple 2190 * times in the result of the builder. We do that by 2191 * constructing a "let" expression that saves the rvalue into a 2192 * temporary variable and then uses the temporary variable in 2193 * place of the expression built by the builder. The complete 2194 * resulting expression is of the form 2195 * <pre> 2196 * (let <b>TYPE</b> <b>TEMP</b> = <b>RVAL</b>; 2197 * in (<b>BUILDER</b>(<b>TEMP</b>))) 2198 * </pre> 2199 * where <code><b>TEMP</b></code> is a newly declared variable 2200 * in the let expression. 2201 */ 2202 JCTree abstractRval(JCTree rval, Type type, TreeBuilder builder) { 2203 rval = TreeInfo.skipParens(rval); 2204 switch (rval.getTag()) { 2205 case LITERAL: 2206 return builder.build(rval); 2207 case IDENT: 2208 JCIdent id = (JCIdent) rval; 2209 if ((id.sym.flags() & FINAL) != 0 && id.sym.owner.kind == MTH) 2210 return builder.build(rval); 2211 } 2212 VarSymbol var = 2213 new VarSymbol(FINAL|SYNTHETIC, 2214 names.fromString( 2215 target.syntheticNameChar() 2216 + "" + rval.hashCode()), 2217 type, 2218 currentMethodSym); 2219 rval = convert(rval,type); 2220 JCVariableDecl def = make.VarDef(var, (JCExpression)rval); // XXX cast 2221 JCTree built = builder.build(make.Ident(var)); 2222 JCTree res = make.LetExpr(def, built); 2223 res.type = built.type; 2224 return res; 2225 } 2226 2227 // same as above, with the type of the temporary variable computed 2228 JCTree abstractRval(JCTree rval, TreeBuilder builder) { 2229 return abstractRval(rval, rval.type, builder); 2230 } 2231 2232 // same as above, but for an expression that may be used as either 2233 // an rvalue or an lvalue. This requires special handling for 2234 // Select expressions, where we place the left-hand-side of the 2235 // select in a temporary, and for Indexed expressions, where we 2236 // place both the indexed expression and the index value in temps. 2237 JCTree abstractLval(JCTree lval, final TreeBuilder builder) { 2238 lval = TreeInfo.skipParens(lval); 2239 switch (lval.getTag()) { 2240 case IDENT: 2241 return builder.build(lval); 2242 case SELECT: { 2243 final JCFieldAccess s = (JCFieldAccess)lval; 2244 JCTree selected = TreeInfo.skipParens(s.selected); 2245 Symbol lid = TreeInfo.symbol(s.selected); 2246 if (lid != null && lid.kind == TYP) return builder.build(lval); 2247 return abstractRval(s.selected, new TreeBuilder() { 2248 public JCTree build(final JCTree selected) { 2249 return builder.build(make.Select((JCExpression)selected, s.sym)); 2250 } 2251 }); 2252 } 2253 case INDEXED: { 2254 final JCArrayAccess i = (JCArrayAccess)lval; 2255 return abstractRval(i.indexed, new TreeBuilder() { 2256 public JCTree build(final JCTree indexed) { 2257 return abstractRval(i.index, syms.intType, new TreeBuilder() { 2258 public JCTree build(final JCTree index) { 2259 JCTree newLval = make.Indexed((JCExpression)indexed, 2260 (JCExpression)index); 2261 newLval.setType(i.type); 2262 return builder.build(newLval); 2263 } 2264 }); 2265 } 2266 }); 2267 } 2268 case TYPECAST: { 2269 return abstractLval(((JCTypeCast)lval).expr, builder); 2270 } 2271 } 2272 throw new AssertionError(lval); 2273 } 2274 2275 // evaluate and discard the first expression, then evaluate the second. 2276 JCTree makeComma(final JCTree expr1, final JCTree expr2) { 2277 return abstractRval(expr1, new TreeBuilder() { 2278 public JCTree build(final JCTree discarded) { 2279 return expr2; 2280 } 2281 }); 2282 } 2283 2284/************************************************************************** 2285 * Translation methods 2286 *************************************************************************/ 2287 2288 /** Visitor argument: enclosing operator node. 2289 */ 2290 private JCExpression enclOp; 2291 2292 /** Visitor method: Translate a single node. 2293 * Attach the source position from the old tree to its replacement tree. 2294 */ 2295 @Override 2296 public <T extends JCTree> T translate(T tree) { 2297 if (tree == null) { 2298 return null; 2299 } else { 2300 make_at(tree.pos()); 2301 T result = super.translate(tree); 2302 if (endPosTable != null && result != tree) { 2303 endPosTable.replaceTree(tree, result); 2304 } 2305 return result; 2306 } 2307 } 2308 2309 /** Visitor method: Translate a single node, boxing or unboxing if needed. 2310 */ 2311 public <T extends JCTree> T translate(T tree, Type type) { 2312 return (tree == null) ? null : boxIfNeeded(translate(tree), type); 2313 } 2314 2315 /** Visitor method: Translate tree. 2316 */ 2317 public <T extends JCTree> T translate(T tree, JCExpression enclOp) { 2318 JCExpression prevEnclOp = this.enclOp; 2319 this.enclOp = enclOp; 2320 T res = translate(tree); 2321 this.enclOp = prevEnclOp; 2322 return res; 2323 } 2324 2325 /** Visitor method: Translate list of trees. 2326 */ 2327 public <T extends JCTree> List<T> translate(List<T> trees, JCExpression enclOp) { 2328 JCExpression prevEnclOp = this.enclOp; 2329 this.enclOp = enclOp; 2330 List<T> res = translate(trees); 2331 this.enclOp = prevEnclOp; 2332 return res; 2333 } 2334 2335 /** Visitor method: Translate list of trees. 2336 */ 2337 public <T extends JCTree> List<T> translate(List<T> trees, Type type) { 2338 if (trees == null) return null; 2339 for (List<T> l = trees; l.nonEmpty(); l = l.tail) 2340 l.head = translate(l.head, type); 2341 return trees; 2342 } 2343 2344 public void visitPackageDef(JCPackageDecl tree) { 2345 if (!needPackageInfoClass(tree)) 2346 return; 2347 2348 Name name = names.package_info; 2349 long flags = Flags.ABSTRACT | Flags.INTERFACE; 2350 // package-info is marked SYNTHETIC in JDK 1.6 and later releases 2351 flags = flags | Flags.SYNTHETIC; 2352 JCClassDecl packageAnnotationsClass 2353 = make.ClassDef(make.Modifiers(flags, tree.getAnnotations()), 2354 name, List.<JCTypeParameter>nil(), 2355 null, List.<JCExpression>nil(), List.<JCTree>nil()); 2356 ClassSymbol c = tree.packge.package_info; 2357 c.flags_field |= flags; 2358 c.setAttributes(tree.packge); 2359 ClassType ctype = (ClassType) c.type; 2360 ctype.supertype_field = syms.objectType; 2361 ctype.interfaces_field = List.nil(); 2362 packageAnnotationsClass.sym = c; 2363 2364 translated.append(packageAnnotationsClass); 2365 } 2366 // where 2367 private boolean needPackageInfoClass(JCPackageDecl pd) { 2368 switch (pkginfoOpt) { 2369 case ALWAYS: 2370 return true; 2371 case LEGACY: 2372 return pd.getAnnotations().nonEmpty(); 2373 case NONEMPTY: 2374 for (Attribute.Compound a : 2375 pd.packge.getDeclarationAttributes()) { 2376 Attribute.RetentionPolicy p = types.getRetention(a); 2377 if (p != Attribute.RetentionPolicy.SOURCE) 2378 return true; 2379 } 2380 return false; 2381 } 2382 throw new AssertionError(); 2383 } 2384 2385 public void visitClassDef(JCClassDecl tree) { 2386 Env<AttrContext> prevEnv = attrEnv; 2387 ClassSymbol currentClassPrev = currentClass; 2388 MethodSymbol currentMethodSymPrev = currentMethodSym; 2389 2390 currentClass = tree.sym; 2391 currentMethodSym = null; 2392 attrEnv = typeEnvs.remove(currentClass); 2393 if (attrEnv == null) 2394 attrEnv = prevEnv; 2395 2396 classdefs.put(currentClass, tree); 2397 2398 proxies = proxies.dup(currentClass); 2399 List<VarSymbol> prevOuterThisStack = outerThisStack; 2400 2401 // If this is an enum definition 2402 if ((tree.mods.flags & ENUM) != 0 && 2403 (types.supertype(currentClass.type).tsym.flags() & ENUM) == 0) 2404 visitEnumDef(tree); 2405 2406 // If this is a nested class, define a this$n field for 2407 // it and add to proxies. 2408 JCVariableDecl otdef = null; 2409 if (currentClass.hasOuterInstance()) 2410 otdef = outerThisDef(tree.pos, currentClass); 2411 2412 // If this is a local class, define proxies for all its free variables. 2413 List<JCVariableDecl> fvdefs = freevarDefs( 2414 tree.pos, freevars(currentClass), currentClass); 2415 2416 // Recursively translate superclass, interfaces. 2417 tree.extending = translate(tree.extending); 2418 tree.implementing = translate(tree.implementing); 2419 2420 if (currentClass.isLocal()) { 2421 ClassSymbol encl = currentClass.owner.enclClass(); 2422 if (encl.trans_local == null) { 2423 encl.trans_local = List.nil(); 2424 } 2425 encl.trans_local = encl.trans_local.prepend(currentClass); 2426 } 2427 2428 // Recursively translate members, taking into account that new members 2429 // might be created during the translation and prepended to the member 2430 // list `tree.defs'. 2431 List<JCTree> seen = List.nil(); 2432 while (tree.defs != seen) { 2433 List<JCTree> unseen = tree.defs; 2434 for (List<JCTree> l = unseen; l.nonEmpty() && l != seen; l = l.tail) { 2435 JCTree outermostMemberDefPrev = outermostMemberDef; 2436 if (outermostMemberDefPrev == null) outermostMemberDef = l.head; 2437 l.head = translate(l.head); 2438 outermostMemberDef = outermostMemberDefPrev; 2439 } 2440 seen = unseen; 2441 } 2442 2443 // Convert a protected modifier to public, mask static modifier. 2444 if ((tree.mods.flags & PROTECTED) != 0) tree.mods.flags |= PUBLIC; 2445 tree.mods.flags &= ClassFlags; 2446 2447 // Convert name to flat representation, replacing '.' by '$'. 2448 tree.name = Convert.shortName(currentClass.flatName()); 2449 2450 // Add this$n and free variables proxy definitions to class. 2451 2452 for (List<JCVariableDecl> l = fvdefs; l.nonEmpty(); l = l.tail) { 2453 tree.defs = tree.defs.prepend(l.head); 2454 enterSynthetic(tree.pos(), l.head.sym, currentClass.members()); 2455 } 2456 if (currentClass.hasOuterInstance()) { 2457 tree.defs = tree.defs.prepend(otdef); 2458 enterSynthetic(tree.pos(), otdef.sym, currentClass.members()); 2459 } 2460 2461 proxies = proxies.leave(); 2462 outerThisStack = prevOuterThisStack; 2463 2464 // Append translated tree to `translated' queue. 2465 translated.append(tree); 2466 2467 attrEnv = prevEnv; 2468 currentClass = currentClassPrev; 2469 currentMethodSym = currentMethodSymPrev; 2470 2471 // Return empty block {} as a placeholder for an inner class. 2472 result = make_at(tree.pos()).Block(0, List.<JCStatement>nil()); 2473 } 2474 2475 /** Translate an enum class. */ 2476 private void visitEnumDef(JCClassDecl tree) { 2477 make_at(tree.pos()); 2478 2479 // add the supertype, if needed 2480 if (tree.extending == null) 2481 tree.extending = make.Type(types.supertype(tree.type)); 2482 2483 // classOfType adds a cache field to tree.defs 2484 JCExpression e_class = classOfType(tree.sym.type, tree.pos()). 2485 setType(types.erasure(syms.classType)); 2486 2487 // process each enumeration constant, adding implicit constructor parameters 2488 int nextOrdinal = 0; 2489 ListBuffer<JCExpression> values = new ListBuffer<>(); 2490 ListBuffer<JCTree> enumDefs = new ListBuffer<>(); 2491 ListBuffer<JCTree> otherDefs = new ListBuffer<>(); 2492 for (List<JCTree> defs = tree.defs; 2493 defs.nonEmpty(); 2494 defs=defs.tail) { 2495 if (defs.head.hasTag(VARDEF) && (((JCVariableDecl) defs.head).mods.flags & ENUM) != 0) { 2496 JCVariableDecl var = (JCVariableDecl)defs.head; 2497 visitEnumConstantDef(var, nextOrdinal++); 2498 values.append(make.QualIdent(var.sym)); 2499 enumDefs.append(var); 2500 } else { 2501 otherDefs.append(defs.head); 2502 } 2503 } 2504 2505 // private static final T[] #VALUES = { a, b, c }; 2506 Name valuesName = names.fromString(target.syntheticNameChar() + "VALUES"); 2507 while (tree.sym.members().findFirst(valuesName) != null) // avoid name clash 2508 valuesName = names.fromString(valuesName + "" + target.syntheticNameChar()); 2509 Type arrayType = new ArrayType(types.erasure(tree.type), 2510 syms.arrayClass, Type.noAnnotations); 2511 VarSymbol valuesVar = new VarSymbol(PRIVATE|FINAL|STATIC|SYNTHETIC, 2512 valuesName, 2513 arrayType, 2514 tree.type.tsym); 2515 JCNewArray newArray = make.NewArray(make.Type(types.erasure(tree.type)), 2516 List.<JCExpression>nil(), 2517 values.toList()); 2518 newArray.type = arrayType; 2519 enumDefs.append(make.VarDef(valuesVar, newArray)); 2520 tree.sym.members().enter(valuesVar); 2521 2522 Symbol valuesSym = lookupMethod(tree.pos(), names.values, 2523 tree.type, List.<Type>nil()); 2524 List<JCStatement> valuesBody; 2525 if (useClone()) { 2526 // return (T[]) $VALUES.clone(); 2527 JCTypeCast valuesResult = 2528 make.TypeCast(valuesSym.type.getReturnType(), 2529 make.App(make.Select(make.Ident(valuesVar), 2530 syms.arrayCloneMethod))); 2531 valuesBody = List.<JCStatement>of(make.Return(valuesResult)); 2532 } else { 2533 // template: T[] $result = new T[$values.length]; 2534 Name resultName = names.fromString(target.syntheticNameChar() + "result"); 2535 while (tree.sym.members().findFirst(resultName) != null) // avoid name clash 2536 resultName = names.fromString(resultName + "" + target.syntheticNameChar()); 2537 VarSymbol resultVar = new VarSymbol(FINAL|SYNTHETIC, 2538 resultName, 2539 arrayType, 2540 valuesSym); 2541 JCNewArray resultArray = make.NewArray(make.Type(types.erasure(tree.type)), 2542 List.of(make.Select(make.Ident(valuesVar), syms.lengthVar)), 2543 null); 2544 resultArray.type = arrayType; 2545 JCVariableDecl decl = make.VarDef(resultVar, resultArray); 2546 2547 // template: System.arraycopy($VALUES, 0, $result, 0, $VALUES.length); 2548 if (systemArraycopyMethod == null) { 2549 systemArraycopyMethod = 2550 new MethodSymbol(PUBLIC | STATIC, 2551 names.fromString("arraycopy"), 2552 new MethodType(List.<Type>of(syms.objectType, 2553 syms.intType, 2554 syms.objectType, 2555 syms.intType, 2556 syms.intType), 2557 syms.voidType, 2558 List.<Type>nil(), 2559 syms.methodClass), 2560 syms.systemType.tsym); 2561 } 2562 JCStatement copy = 2563 make.Exec(make.App(make.Select(make.Ident(syms.systemType.tsym), 2564 systemArraycopyMethod), 2565 List.of(make.Ident(valuesVar), make.Literal(0), 2566 make.Ident(resultVar), make.Literal(0), 2567 make.Select(make.Ident(valuesVar), syms.lengthVar)))); 2568 2569 // template: return $result; 2570 JCStatement ret = make.Return(make.Ident(resultVar)); 2571 valuesBody = List.<JCStatement>of(decl, copy, ret); 2572 } 2573 2574 JCMethodDecl valuesDef = 2575 make.MethodDef((MethodSymbol)valuesSym, make.Block(0, valuesBody)); 2576 2577 enumDefs.append(valuesDef); 2578 2579 if (debugLower) 2580 System.err.println(tree.sym + ".valuesDef = " + valuesDef); 2581 2582 /** The template for the following code is: 2583 * 2584 * public static E valueOf(String name) { 2585 * return (E)Enum.valueOf(E.class, name); 2586 * } 2587 * 2588 * where E is tree.sym 2589 */ 2590 MethodSymbol valueOfSym = lookupMethod(tree.pos(), 2591 names.valueOf, 2592 tree.sym.type, 2593 List.of(syms.stringType)); 2594 Assert.check((valueOfSym.flags() & STATIC) != 0); 2595 VarSymbol nameArgSym = valueOfSym.params.head; 2596 JCIdent nameVal = make.Ident(nameArgSym); 2597 JCStatement enum_ValueOf = 2598 make.Return(make.TypeCast(tree.sym.type, 2599 makeCall(make.Ident(syms.enumSym), 2600 names.valueOf, 2601 List.of(e_class, nameVal)))); 2602 JCMethodDecl valueOf = make.MethodDef(valueOfSym, 2603 make.Block(0, List.of(enum_ValueOf))); 2604 nameVal.sym = valueOf.params.head.sym; 2605 if (debugLower) 2606 System.err.println(tree.sym + ".valueOf = " + valueOf); 2607 enumDefs.append(valueOf); 2608 2609 enumDefs.appendList(otherDefs.toList()); 2610 tree.defs = enumDefs.toList(); 2611 } 2612 // where 2613 private MethodSymbol systemArraycopyMethod; 2614 private boolean useClone() { 2615 try { 2616 return syms.objectType.tsym.members().findFirst(names.clone) != null; 2617 } 2618 catch (CompletionFailure e) { 2619 return false; 2620 } 2621 } 2622 2623 /** Translate an enumeration constant and its initializer. */ 2624 private void visitEnumConstantDef(JCVariableDecl var, int ordinal) { 2625 JCNewClass varDef = (JCNewClass)var.init; 2626 varDef.args = varDef.args. 2627 prepend(makeLit(syms.intType, ordinal)). 2628 prepend(makeLit(syms.stringType, var.name.toString())); 2629 } 2630 2631 public void visitMethodDef(JCMethodDecl tree) { 2632 if (tree.name == names.init && (currentClass.flags_field&ENUM) != 0) { 2633 // Add "String $enum$name, int $enum$ordinal" to the beginning of the 2634 // argument list for each constructor of an enum. 2635 JCVariableDecl nameParam = make_at(tree.pos()). 2636 Param(names.fromString(target.syntheticNameChar() + 2637 "enum" + target.syntheticNameChar() + "name"), 2638 syms.stringType, tree.sym); 2639 nameParam.mods.flags |= SYNTHETIC; nameParam.sym.flags_field |= SYNTHETIC; 2640 JCVariableDecl ordParam = make. 2641 Param(names.fromString(target.syntheticNameChar() + 2642 "enum" + target.syntheticNameChar() + 2643 "ordinal"), 2644 syms.intType, tree.sym); 2645 ordParam.mods.flags |= SYNTHETIC; ordParam.sym.flags_field |= SYNTHETIC; 2646 2647 tree.params = tree.params.prepend(ordParam).prepend(nameParam); 2648 2649 MethodSymbol m = tree.sym; 2650 m.extraParams = m.extraParams.prepend(ordParam.sym); 2651 m.extraParams = m.extraParams.prepend(nameParam.sym); 2652 Type olderasure = m.erasure(types); 2653 m.erasure_field = new MethodType( 2654 olderasure.getParameterTypes().prepend(syms.intType).prepend(syms.stringType), 2655 olderasure.getReturnType(), 2656 olderasure.getThrownTypes(), 2657 syms.methodClass); 2658 } 2659 2660 JCMethodDecl prevMethodDef = currentMethodDef; 2661 MethodSymbol prevMethodSym = currentMethodSym; 2662 try { 2663 currentMethodDef = tree; 2664 currentMethodSym = tree.sym; 2665 visitMethodDefInternal(tree); 2666 } finally { 2667 currentMethodDef = prevMethodDef; 2668 currentMethodSym = prevMethodSym; 2669 } 2670 } 2671 //where 2672 private void visitMethodDefInternal(JCMethodDecl tree) { 2673 if (tree.name == names.init && 2674 (currentClass.isInner() || currentClass.isLocal())) { 2675 // We are seeing a constructor of an inner class. 2676 MethodSymbol m = tree.sym; 2677 2678 // Push a new proxy scope for constructor parameters. 2679 // and create definitions for any this$n and proxy parameters. 2680 proxies = proxies.dup(m); 2681 List<VarSymbol> prevOuterThisStack = outerThisStack; 2682 List<VarSymbol> fvs = freevars(currentClass); 2683 JCVariableDecl otdef = null; 2684 if (currentClass.hasOuterInstance()) 2685 otdef = outerThisDef(tree.pos, m); 2686 List<JCVariableDecl> fvdefs = freevarDefs(tree.pos, fvs, m, PARAMETER); 2687 2688 // Recursively translate result type, parameters and thrown list. 2689 tree.restype = translate(tree.restype); 2690 tree.params = translateVarDefs(tree.params); 2691 tree.thrown = translate(tree.thrown); 2692 2693 // when compiling stubs, don't process body 2694 if (tree.body == null) { 2695 result = tree; 2696 return; 2697 } 2698 2699 // Add this$n (if needed) in front of and free variables behind 2700 // constructor parameter list. 2701 tree.params = tree.params.appendList(fvdefs); 2702 if (currentClass.hasOuterInstance()) 2703 tree.params = tree.params.prepend(otdef); 2704 2705 // If this is an initial constructor, i.e., it does not start with 2706 // this(...), insert initializers for this$n and proxies 2707 // before (pre-1.4, after) the call to superclass constructor. 2708 JCStatement selfCall = translate(tree.body.stats.head); 2709 2710 List<JCStatement> added = List.nil(); 2711 if (fvs.nonEmpty()) { 2712 List<Type> addedargtypes = List.nil(); 2713 for (List<VarSymbol> l = fvs; l.nonEmpty(); l = l.tail) { 2714 if (TreeInfo.isInitialConstructor(tree)) { 2715 final Name pName = proxyName(l.head.name); 2716 m.capturedLocals = 2717 m.capturedLocals.append((VarSymbol) 2718 (proxies.findFirst(pName))); 2719 added = added.prepend( 2720 initField(tree.body.pos, pName)); 2721 } 2722 addedargtypes = addedargtypes.prepend(l.head.erasure(types)); 2723 } 2724 Type olderasure = m.erasure(types); 2725 m.erasure_field = new MethodType( 2726 olderasure.getParameterTypes().appendList(addedargtypes), 2727 olderasure.getReturnType(), 2728 olderasure.getThrownTypes(), 2729 syms.methodClass); 2730 } 2731 if (currentClass.hasOuterInstance() && 2732 TreeInfo.isInitialConstructor(tree)) 2733 { 2734 added = added.prepend(initOuterThis(tree.body.pos)); 2735 } 2736 2737 // pop local variables from proxy stack 2738 proxies = proxies.leave(); 2739 2740 // recursively translate following local statements and 2741 // combine with this- or super-call 2742 List<JCStatement> stats = translate(tree.body.stats.tail); 2743 tree.body.stats = stats.prepend(selfCall).prependList(added); 2744 outerThisStack = prevOuterThisStack; 2745 } else { 2746 Map<Symbol, Symbol> prevLambdaTranslationMap = 2747 lambdaTranslationMap; 2748 try { 2749 lambdaTranslationMap = (tree.sym.flags() & SYNTHETIC) != 0 && 2750 tree.sym.name.startsWith(names.lambda) ? 2751 makeTranslationMap(tree) : null; 2752 super.visitMethodDef(tree); 2753 } finally { 2754 lambdaTranslationMap = prevLambdaTranslationMap; 2755 } 2756 } 2757 result = tree; 2758 } 2759 //where 2760 private Map<Symbol, Symbol> makeTranslationMap(JCMethodDecl tree) { 2761 Map<Symbol, Symbol> translationMap = new HashMap<>(); 2762 for (JCVariableDecl vd : tree.params) { 2763 Symbol p = vd.sym; 2764 if (p != p.baseSymbol()) { 2765 translationMap.put(p.baseSymbol(), p); 2766 } 2767 } 2768 return translationMap; 2769 } 2770 2771 public void visitAnnotatedType(JCAnnotatedType tree) { 2772 // No need to retain type annotations in the tree 2773 // tree.annotations = translate(tree.annotations); 2774 tree.annotations = List.nil(); 2775 tree.underlyingType = translate(tree.underlyingType); 2776 // but maintain type annotations in the type. 2777 if (tree.type.isAnnotated()) { 2778 tree.type = tree.underlyingType.type.annotatedType(tree.type.getAnnotationMirrors()); 2779 } else if (tree.underlyingType.type.isAnnotated()) { 2780 tree.type = tree.underlyingType.type; 2781 } 2782 result = tree; 2783 } 2784 2785 public void visitTypeCast(JCTypeCast tree) { 2786 tree.clazz = translate(tree.clazz); 2787 if (tree.type.isPrimitive() != tree.expr.type.isPrimitive()) 2788 tree.expr = translate(tree.expr, tree.type); 2789 else 2790 tree.expr = translate(tree.expr); 2791 result = tree; 2792 } 2793 2794 public void visitNewClass(JCNewClass tree) { 2795 ClassSymbol c = (ClassSymbol)tree.constructor.owner; 2796 2797 // Box arguments, if necessary 2798 boolean isEnum = (tree.constructor.owner.flags() & ENUM) != 0; 2799 List<Type> argTypes = tree.constructor.type.getParameterTypes(); 2800 if (isEnum) argTypes = argTypes.prepend(syms.intType).prepend(syms.stringType); 2801 tree.args = boxArgs(argTypes, tree.args, tree.varargsElement); 2802 tree.varargsElement = null; 2803 2804 // If created class is local, add free variables after 2805 // explicit constructor arguments. 2806 if (c.isLocal()) { 2807 tree.args = tree.args.appendList(loadFreevars(tree.pos(), freevars(c))); 2808 } 2809 2810 // If an access constructor is used, append null as a last argument. 2811 Symbol constructor = accessConstructor(tree.pos(), tree.constructor); 2812 if (constructor != tree.constructor) { 2813 tree.args = tree.args.append(makeNull()); 2814 tree.constructor = constructor; 2815 } 2816 2817 // If created class has an outer instance, and new is qualified, pass 2818 // qualifier as first argument. If new is not qualified, pass the 2819 // correct outer instance as first argument. 2820 if (c.hasOuterInstance()) { 2821 JCExpression thisArg; 2822 if (tree.encl != null) { 2823 thisArg = attr.makeNullCheck(translate(tree.encl)); 2824 thisArg.type = tree.encl.type; 2825 } else if (c.isLocal()) { 2826 // local class 2827 thisArg = makeThis(tree.pos(), c.type.getEnclosingType().tsym); 2828 } else { 2829 // nested class 2830 thisArg = makeOwnerThis(tree.pos(), c, false); 2831 } 2832 tree.args = tree.args.prepend(thisArg); 2833 } 2834 tree.encl = null; 2835 2836 // If we have an anonymous class, create its flat version, rather 2837 // than the class or interface following new. 2838 if (tree.def != null) { 2839 translate(tree.def); 2840 tree.clazz = access(make_at(tree.clazz.pos()).Ident(tree.def.sym)); 2841 tree.def = null; 2842 } else { 2843 tree.clazz = access(c, tree.clazz, enclOp, false); 2844 } 2845 result = tree; 2846 } 2847 2848 // Simplify conditionals with known constant controlling expressions. 2849 // This allows us to avoid generating supporting declarations for 2850 // the dead code, which will not be eliminated during code generation. 2851 // Note that Flow.isFalse and Flow.isTrue only return true 2852 // for constant expressions in the sense of JLS 15.27, which 2853 // are guaranteed to have no side-effects. More aggressive 2854 // constant propagation would require that we take care to 2855 // preserve possible side-effects in the condition expression. 2856 2857 // One common case is equality expressions involving a constant and null. 2858 // Since null is not a constant expression (because null cannot be 2859 // represented in the constant pool), equality checks involving null are 2860 // not captured by Flow.isTrue/isFalse. 2861 // Equality checks involving a constant and null, e.g. 2862 // "" == null 2863 // are safe to simplify as no side-effects can occur. 2864 2865 private boolean isTrue(JCTree exp) { 2866 if (exp.type.isTrue()) 2867 return true; 2868 Boolean b = expValue(exp); 2869 return b == null ? false : b; 2870 } 2871 private boolean isFalse(JCTree exp) { 2872 if (exp.type.isFalse()) 2873 return true; 2874 Boolean b = expValue(exp); 2875 return b == null ? false : !b; 2876 } 2877 /* look for (in)equality relations involving null. 2878 * return true - if expression is always true 2879 * false - if expression is always false 2880 * null - if expression cannot be eliminated 2881 */ 2882 private Boolean expValue(JCTree exp) { 2883 while (exp.hasTag(PARENS)) 2884 exp = ((JCParens)exp).expr; 2885 2886 boolean eq; 2887 switch (exp.getTag()) { 2888 case EQ: eq = true; break; 2889 case NE: eq = false; break; 2890 default: 2891 return null; 2892 } 2893 2894 // we have a JCBinary(EQ|NE) 2895 // check if we have two literals (constants or null) 2896 JCBinary b = (JCBinary)exp; 2897 if (b.lhs.type.hasTag(BOT)) return expValueIsNull(eq, b.rhs); 2898 if (b.rhs.type.hasTag(BOT)) return expValueIsNull(eq, b.lhs); 2899 return null; 2900 } 2901 private Boolean expValueIsNull(boolean eq, JCTree t) { 2902 if (t.type.hasTag(BOT)) return Boolean.valueOf(eq); 2903 if (t.hasTag(LITERAL)) return Boolean.valueOf(!eq); 2904 return null; 2905 } 2906 2907 /** Visitor method for conditional expressions. 2908 */ 2909 @Override 2910 public void visitConditional(JCConditional tree) { 2911 JCTree cond = tree.cond = translate(tree.cond, syms.booleanType); 2912 if (isTrue(cond)) { 2913 result = convert(translate(tree.truepart, tree.type), tree.type); 2914 addPrunedInfo(cond); 2915 } else if (isFalse(cond)) { 2916 result = convert(translate(tree.falsepart, tree.type), tree.type); 2917 addPrunedInfo(cond); 2918 } else { 2919 // Condition is not a compile-time constant. 2920 tree.truepart = translate(tree.truepart, tree.type); 2921 tree.falsepart = translate(tree.falsepart, tree.type); 2922 result = tree; 2923 } 2924 } 2925//where 2926 private JCTree convert(JCTree tree, Type pt) { 2927 if (tree.type == pt || tree.type.hasTag(BOT)) 2928 return tree; 2929 JCTree result = make_at(tree.pos()).TypeCast(make.Type(pt), (JCExpression)tree); 2930 result.type = (tree.type.constValue() != null) ? cfolder.coerce(tree.type, pt) 2931 : pt; 2932 return result; 2933 } 2934 2935 /** Visitor method for if statements. 2936 */ 2937 public void visitIf(JCIf tree) { 2938 JCTree cond = tree.cond = translate(tree.cond, syms.booleanType); 2939 if (isTrue(cond)) { 2940 result = translate(tree.thenpart); 2941 addPrunedInfo(cond); 2942 } else if (isFalse(cond)) { 2943 if (tree.elsepart != null) { 2944 result = translate(tree.elsepart); 2945 } else { 2946 result = make.Skip(); 2947 } 2948 addPrunedInfo(cond); 2949 } else { 2950 // Condition is not a compile-time constant. 2951 tree.thenpart = translate(tree.thenpart); 2952 tree.elsepart = translate(tree.elsepart); 2953 result = tree; 2954 } 2955 } 2956 2957 /** Visitor method for assert statements. Translate them away. 2958 */ 2959 public void visitAssert(JCAssert tree) { 2960 DiagnosticPosition detailPos = (tree.detail == null) ? tree.pos() : tree.detail.pos(); 2961 tree.cond = translate(tree.cond, syms.booleanType); 2962 if (!tree.cond.type.isTrue()) { 2963 JCExpression cond = assertFlagTest(tree.pos()); 2964 List<JCExpression> exnArgs = (tree.detail == null) ? 2965 List.<JCExpression>nil() : List.of(translate(tree.detail)); 2966 if (!tree.cond.type.isFalse()) { 2967 cond = makeBinary 2968 (AND, 2969 cond, 2970 makeUnary(NOT, tree.cond)); 2971 } 2972 result = 2973 make.If(cond, 2974 make_at(tree). 2975 Throw(makeNewClass(syms.assertionErrorType, exnArgs)), 2976 null); 2977 } else { 2978 result = make.Skip(); 2979 } 2980 } 2981 2982 public void visitApply(JCMethodInvocation tree) { 2983 Symbol meth = TreeInfo.symbol(tree.meth); 2984 List<Type> argtypes = meth.type.getParameterTypes(); 2985 if (meth.name == names.init && meth.owner == syms.enumSym) 2986 argtypes = argtypes.tail.tail; 2987 tree.args = boxArgs(argtypes, tree.args, tree.varargsElement); 2988 tree.varargsElement = null; 2989 Name methName = TreeInfo.name(tree.meth); 2990 if (meth.name==names.init) { 2991 // We are seeing a this(...) or super(...) constructor call. 2992 // If an access constructor is used, append null as a last argument. 2993 Symbol constructor = accessConstructor(tree.pos(), meth); 2994 if (constructor != meth) { 2995 tree.args = tree.args.append(makeNull()); 2996 TreeInfo.setSymbol(tree.meth, constructor); 2997 } 2998 2999 // If we are calling a constructor of a local class, add 3000 // free variables after explicit constructor arguments. 3001 ClassSymbol c = (ClassSymbol)constructor.owner; 3002 if (c.isLocal()) { 3003 tree.args = tree.args.appendList(loadFreevars(tree.pos(), freevars(c))); 3004 } 3005 3006 // If we are calling a constructor of an enum class, pass 3007 // along the name and ordinal arguments 3008 if ((c.flags_field&ENUM) != 0 || c.getQualifiedName() == names.java_lang_Enum) { 3009 List<JCVariableDecl> params = currentMethodDef.params; 3010 if (currentMethodSym.owner.hasOuterInstance()) 3011 params = params.tail; // drop this$n 3012 tree.args = tree.args 3013 .prepend(make_at(tree.pos()).Ident(params.tail.head.sym)) // ordinal 3014 .prepend(make.Ident(params.head.sym)); // name 3015 } 3016 3017 // If we are calling a constructor of a class with an outer 3018 // instance, and the call 3019 // is qualified, pass qualifier as first argument in front of 3020 // the explicit constructor arguments. If the call 3021 // is not qualified, pass the correct outer instance as 3022 // first argument. 3023 if (c.hasOuterInstance()) { 3024 JCExpression thisArg; 3025 if (tree.meth.hasTag(SELECT)) { 3026 thisArg = attr. 3027 makeNullCheck(translate(((JCFieldAccess) tree.meth).selected)); 3028 tree.meth = make.Ident(constructor); 3029 ((JCIdent) tree.meth).name = methName; 3030 } else if (c.isLocal() || methName == names._this){ 3031 // local class or this() call 3032 thisArg = makeThis(tree.meth.pos(), c.type.getEnclosingType().tsym); 3033 } else { 3034 // super() call of nested class - never pick 'this' 3035 thisArg = makeOwnerThisN(tree.meth.pos(), c, false); 3036 } 3037 tree.args = tree.args.prepend(thisArg); 3038 } 3039 } else { 3040 // We are seeing a normal method invocation; translate this as usual. 3041 tree.meth = translate(tree.meth); 3042 3043 // If the translated method itself is an Apply tree, we are 3044 // seeing an access method invocation. In this case, append 3045 // the method arguments to the arguments of the access method. 3046 if (tree.meth.hasTag(APPLY)) { 3047 JCMethodInvocation app = (JCMethodInvocation)tree.meth; 3048 app.args = tree.args.prependList(app.args); 3049 result = app; 3050 return; 3051 } 3052 } 3053 result = tree; 3054 } 3055 3056 List<JCExpression> boxArgs(List<Type> parameters, List<JCExpression> _args, Type varargsElement) { 3057 List<JCExpression> args = _args; 3058 if (parameters.isEmpty()) return args; 3059 boolean anyChanges = false; 3060 ListBuffer<JCExpression> result = new ListBuffer<>(); 3061 while (parameters.tail.nonEmpty()) { 3062 JCExpression arg = translate(args.head, parameters.head); 3063 anyChanges |= (arg != args.head); 3064 result.append(arg); 3065 args = args.tail; 3066 parameters = parameters.tail; 3067 } 3068 Type parameter = parameters.head; 3069 if (varargsElement != null) { 3070 anyChanges = true; 3071 ListBuffer<JCExpression> elems = new ListBuffer<>(); 3072 while (args.nonEmpty()) { 3073 JCExpression arg = translate(args.head, varargsElement); 3074 elems.append(arg); 3075 args = args.tail; 3076 } 3077 JCNewArray boxedArgs = make.NewArray(make.Type(varargsElement), 3078 List.<JCExpression>nil(), 3079 elems.toList()); 3080 boxedArgs.type = new ArrayType(varargsElement, syms.arrayClass, 3081 Type.noAnnotations); 3082 result.append(boxedArgs); 3083 } else { 3084 if (args.length() != 1) throw new AssertionError(args); 3085 JCExpression arg = translate(args.head, parameter); 3086 anyChanges |= (arg != args.head); 3087 result.append(arg); 3088 if (!anyChanges) return _args; 3089 } 3090 return result.toList(); 3091 } 3092 3093 /** Expand a boxing or unboxing conversion if needed. */ 3094 @SuppressWarnings("unchecked") // XXX unchecked 3095 <T extends JCTree> T boxIfNeeded(T tree, Type type) { 3096 boolean havePrimitive = tree.type.isPrimitive(); 3097 if (havePrimitive == type.isPrimitive()) 3098 return tree; 3099 if (havePrimitive) { 3100 Type unboxedTarget = types.unboxedType(type); 3101 if (!unboxedTarget.hasTag(NONE)) { 3102 if (!types.isSubtype(tree.type, unboxedTarget)) //e.g. Character c = 89; 3103 tree.type = unboxedTarget.constType(tree.type.constValue()); 3104 return (T)boxPrimitive((JCExpression)tree, type); 3105 } else { 3106 tree = (T)boxPrimitive((JCExpression)tree); 3107 } 3108 } else { 3109 tree = (T)unbox((JCExpression)tree, type); 3110 } 3111 return tree; 3112 } 3113 3114 /** Box up a single primitive expression. */ 3115 JCExpression boxPrimitive(JCExpression tree) { 3116 return boxPrimitive(tree, types.boxedClass(tree.type).type); 3117 } 3118 3119 /** Box up a single primitive expression. */ 3120 JCExpression boxPrimitive(JCExpression tree, Type box) { 3121 make_at(tree.pos()); 3122 Symbol valueOfSym = lookupMethod(tree.pos(), 3123 names.valueOf, 3124 box, 3125 List.<Type>nil() 3126 .prepend(tree.type)); 3127 return make.App(make.QualIdent(valueOfSym), List.of(tree)); 3128 } 3129 3130 /** Unbox an object to a primitive value. */ 3131 JCExpression unbox(JCExpression tree, Type primitive) { 3132 Type unboxedType = types.unboxedType(tree.type); 3133 if (unboxedType.hasTag(NONE)) { 3134 unboxedType = primitive; 3135 if (!unboxedType.isPrimitive()) 3136 throw new AssertionError(unboxedType); 3137 make_at(tree.pos()); 3138 tree = make.TypeCast(types.boxedClass(unboxedType).type, tree); 3139 } else { 3140 // There must be a conversion from unboxedType to primitive. 3141 if (!types.isSubtype(unboxedType, primitive)) 3142 throw new AssertionError(tree); 3143 } 3144 make_at(tree.pos()); 3145 Symbol valueSym = lookupMethod(tree.pos(), 3146 unboxedType.tsym.name.append(names.Value), // x.intValue() 3147 tree.type, 3148 List.<Type>nil()); 3149 return make.App(make.Select(tree, valueSym)); 3150 } 3151 3152 /** Visitor method for parenthesized expressions. 3153 * If the subexpression has changed, omit the parens. 3154 */ 3155 public void visitParens(JCParens tree) { 3156 JCTree expr = translate(tree.expr); 3157 result = ((expr == tree.expr) ? tree : expr); 3158 } 3159 3160 public void visitIndexed(JCArrayAccess tree) { 3161 tree.indexed = translate(tree.indexed); 3162 tree.index = translate(tree.index, syms.intType); 3163 result = tree; 3164 } 3165 3166 public void visitAssign(JCAssign tree) { 3167 tree.lhs = translate(tree.lhs, tree); 3168 tree.rhs = translate(tree.rhs, tree.lhs.type); 3169 3170 // If translated left hand side is an Apply, we are 3171 // seeing an access method invocation. In this case, append 3172 // right hand side as last argument of the access method. 3173 if (tree.lhs.hasTag(APPLY)) { 3174 JCMethodInvocation app = (JCMethodInvocation)tree.lhs; 3175 app.args = List.of(tree.rhs).prependList(app.args); 3176 result = app; 3177 } else { 3178 result = tree; 3179 } 3180 } 3181 3182 public void visitAssignop(final JCAssignOp tree) { 3183 JCTree lhsAccess = access(TreeInfo.skipParens(tree.lhs)); 3184 final boolean boxingReq = !tree.lhs.type.isPrimitive() && 3185 tree.operator.type.getReturnType().isPrimitive(); 3186 3187 if (boxingReq || lhsAccess.hasTag(APPLY)) { 3188 // boxing required; need to rewrite as x = (unbox typeof x)(x op y); 3189 // or if x == (typeof x)z then z = (unbox typeof x)((typeof x)z op y) 3190 // (but without recomputing x) 3191 JCTree newTree = abstractLval(tree.lhs, new TreeBuilder() { 3192 public JCTree build(final JCTree lhs) { 3193 JCTree.Tag newTag = tree.getTag().noAssignOp(); 3194 // Erasure (TransTypes) can change the type of 3195 // tree.lhs. However, we can still get the 3196 // unerased type of tree.lhs as it is stored 3197 // in tree.type in Attr. 3198 Symbol newOperator = rs.resolveBinaryOperator(tree.pos(), 3199 newTag, 3200 attrEnv, 3201 tree.type, 3202 tree.rhs.type); 3203 JCExpression expr = (JCExpression)lhs; 3204 if (expr.type != tree.type) 3205 expr = make.TypeCast(tree.type, expr); 3206 JCBinary opResult = make.Binary(newTag, expr, tree.rhs); 3207 opResult.operator = newOperator; 3208 opResult.type = newOperator.type.getReturnType(); 3209 JCExpression newRhs = boxingReq ? 3210 make.TypeCast(types.unboxedType(tree.type), opResult) : 3211 opResult; 3212 return make.Assign((JCExpression)lhs, newRhs).setType(tree.type); 3213 } 3214 }); 3215 result = translate(newTree); 3216 return; 3217 } 3218 tree.lhs = translate(tree.lhs, tree); 3219 tree.rhs = translate(tree.rhs, tree.operator.type.getParameterTypes().tail.head); 3220 3221 // If translated left hand side is an Apply, we are 3222 // seeing an access method invocation. In this case, append 3223 // right hand side as last argument of the access method. 3224 if (tree.lhs.hasTag(APPLY)) { 3225 JCMethodInvocation app = (JCMethodInvocation)tree.lhs; 3226 // if operation is a += on strings, 3227 // make sure to convert argument to string 3228 JCExpression rhs = (((OperatorSymbol)tree.operator).opcode == string_add) 3229 ? makeString(tree.rhs) 3230 : tree.rhs; 3231 app.args = List.of(rhs).prependList(app.args); 3232 result = app; 3233 } else { 3234 result = tree; 3235 } 3236 } 3237 3238 /** Lower a tree of the form e++ or e-- where e is an object type */ 3239 JCTree lowerBoxedPostop(final JCUnary tree) { 3240 // translate to tmp1=lval(e); tmp2=tmp1; tmp1 OP 1; tmp2 3241 // or 3242 // translate to tmp1=lval(e); tmp2=tmp1; (typeof tree)tmp1 OP 1; tmp2 3243 // where OP is += or -= 3244 final boolean cast = TreeInfo.skipParens(tree.arg).hasTag(TYPECAST); 3245 return abstractLval(tree.arg, new TreeBuilder() { 3246 public JCTree build(final JCTree tmp1) { 3247 return abstractRval(tmp1, tree.arg.type, new TreeBuilder() { 3248 public JCTree build(final JCTree tmp2) { 3249 JCTree.Tag opcode = (tree.hasTag(POSTINC)) 3250 ? PLUS_ASG : MINUS_ASG; 3251 JCTree lhs = cast 3252 ? make.TypeCast(tree.arg.type, (JCExpression)tmp1) 3253 : tmp1; 3254 JCTree update = makeAssignop(opcode, 3255 lhs, 3256 make.Literal(1)); 3257 return makeComma(update, tmp2); 3258 } 3259 }); 3260 } 3261 }); 3262 } 3263 3264 public void visitUnary(JCUnary tree) { 3265 boolean isUpdateOperator = tree.getTag().isIncOrDecUnaryOp(); 3266 if (isUpdateOperator && !tree.arg.type.isPrimitive()) { 3267 switch(tree.getTag()) { 3268 case PREINC: // ++ e 3269 // translate to e += 1 3270 case PREDEC: // -- e 3271 // translate to e -= 1 3272 { 3273 JCTree.Tag opcode = (tree.hasTag(PREINC)) 3274 ? PLUS_ASG : MINUS_ASG; 3275 JCAssignOp newTree = makeAssignop(opcode, 3276 tree.arg, 3277 make.Literal(1)); 3278 result = translate(newTree, tree.type); 3279 return; 3280 } 3281 case POSTINC: // e ++ 3282 case POSTDEC: // e -- 3283 { 3284 result = translate(lowerBoxedPostop(tree), tree.type); 3285 return; 3286 } 3287 } 3288 throw new AssertionError(tree); 3289 } 3290 3291 tree.arg = boxIfNeeded(translate(tree.arg, tree), tree.type); 3292 3293 if (tree.hasTag(NOT) && tree.arg.type.constValue() != null) { 3294 tree.type = cfolder.fold1(bool_not, tree.arg.type); 3295 } 3296 3297 // If translated left hand side is an Apply, we are 3298 // seeing an access method invocation. In this case, return 3299 // that access method invocation as result. 3300 if (isUpdateOperator && tree.arg.hasTag(APPLY)) { 3301 result = tree.arg; 3302 } else { 3303 result = tree; 3304 } 3305 } 3306 3307 public void visitBinary(JCBinary tree) { 3308 List<Type> formals = tree.operator.type.getParameterTypes(); 3309 JCTree lhs = tree.lhs = translate(tree.lhs, formals.head); 3310 switch (tree.getTag()) { 3311 case OR: 3312 if (isTrue(lhs)) { 3313 result = lhs; 3314 return; 3315 } 3316 if (isFalse(lhs)) { 3317 result = translate(tree.rhs, formals.tail.head); 3318 return; 3319 } 3320 break; 3321 case AND: 3322 if (isFalse(lhs)) { 3323 result = lhs; 3324 return; 3325 } 3326 if (isTrue(lhs)) { 3327 result = translate(tree.rhs, formals.tail.head); 3328 return; 3329 } 3330 break; 3331 } 3332 tree.rhs = translate(tree.rhs, formals.tail.head); 3333 result = tree; 3334 } 3335 3336 public void visitIdent(JCIdent tree) { 3337 result = access(tree.sym, tree, enclOp, false); 3338 } 3339 3340 /** Translate away the foreach loop. */ 3341 public void visitForeachLoop(JCEnhancedForLoop tree) { 3342 if (types.elemtype(tree.expr.type) == null) 3343 visitIterableForeachLoop(tree); 3344 else 3345 visitArrayForeachLoop(tree); 3346 } 3347 // where 3348 /** 3349 * A statement of the form 3350 * 3351 * <pre> 3352 * for ( T v : arrayexpr ) stmt; 3353 * </pre> 3354 * 3355 * (where arrayexpr is of an array type) gets translated to 3356 * 3357 * <pre>{@code 3358 * for ( { arraytype #arr = arrayexpr; 3359 * int #len = array.length; 3360 * int #i = 0; }; 3361 * #i < #len; i$++ ) { 3362 * T v = arr$[#i]; 3363 * stmt; 3364 * } 3365 * }</pre> 3366 * 3367 * where #arr, #len, and #i are freshly named synthetic local variables. 3368 */ 3369 private void visitArrayForeachLoop(JCEnhancedForLoop tree) { 3370 make_at(tree.expr.pos()); 3371 VarSymbol arraycache = new VarSymbol(SYNTHETIC, 3372 names.fromString("arr" + target.syntheticNameChar()), 3373 tree.expr.type, 3374 currentMethodSym); 3375 JCStatement arraycachedef = make.VarDef(arraycache, tree.expr); 3376 VarSymbol lencache = new VarSymbol(SYNTHETIC, 3377 names.fromString("len" + target.syntheticNameChar()), 3378 syms.intType, 3379 currentMethodSym); 3380 JCStatement lencachedef = make. 3381 VarDef(lencache, make.Select(make.Ident(arraycache), syms.lengthVar)); 3382 VarSymbol index = new VarSymbol(SYNTHETIC, 3383 names.fromString("i" + target.syntheticNameChar()), 3384 syms.intType, 3385 currentMethodSym); 3386 3387 JCVariableDecl indexdef = make.VarDef(index, make.Literal(INT, 0)); 3388 indexdef.init.type = indexdef.type = syms.intType.constType(0); 3389 3390 List<JCStatement> loopinit = List.of(arraycachedef, lencachedef, indexdef); 3391 JCBinary cond = makeBinary(LT, make.Ident(index), make.Ident(lencache)); 3392 3393 JCExpressionStatement step = make.Exec(makeUnary(PREINC, make.Ident(index))); 3394 3395 Type elemtype = types.elemtype(tree.expr.type); 3396 JCExpression loopvarinit = make.Indexed(make.Ident(arraycache), 3397 make.Ident(index)).setType(elemtype); 3398 JCVariableDecl loopvardef = (JCVariableDecl)make.VarDef(tree.var.mods, 3399 tree.var.name, 3400 tree.var.vartype, 3401 loopvarinit).setType(tree.var.type); 3402 loopvardef.sym = tree.var.sym; 3403 JCBlock body = make. 3404 Block(0, List.of(loopvardef, tree.body)); 3405 3406 result = translate(make. 3407 ForLoop(loopinit, 3408 cond, 3409 List.of(step), 3410 body)); 3411 patchTargets(body, tree, result); 3412 } 3413 /** Patch up break and continue targets. */ 3414 private void patchTargets(JCTree body, final JCTree src, final JCTree dest) { 3415 class Patcher extends TreeScanner { 3416 public void visitBreak(JCBreak tree) { 3417 if (tree.target == src) 3418 tree.target = dest; 3419 } 3420 public void visitContinue(JCContinue tree) { 3421 if (tree.target == src) 3422 tree.target = dest; 3423 } 3424 public void visitClassDef(JCClassDecl tree) {} 3425 } 3426 new Patcher().scan(body); 3427 } 3428 /** 3429 * A statement of the form 3430 * 3431 * <pre> 3432 * for ( T v : coll ) stmt ; 3433 * </pre> 3434 * 3435 * (where coll implements {@code Iterable<? extends T>}) gets translated to 3436 * 3437 * <pre>{@code 3438 * for ( Iterator<? extends T> #i = coll.iterator(); #i.hasNext(); ) { 3439 * T v = (T) #i.next(); 3440 * stmt; 3441 * } 3442 * }</pre> 3443 * 3444 * where #i is a freshly named synthetic local variable. 3445 */ 3446 private void visitIterableForeachLoop(JCEnhancedForLoop tree) { 3447 make_at(tree.expr.pos()); 3448 Type iteratorTarget = syms.objectType; 3449 Type iterableType = types.asSuper(types.cvarUpperBound(tree.expr.type), 3450 syms.iterableType.tsym); 3451 if (iterableType.getTypeArguments().nonEmpty()) 3452 iteratorTarget = types.erasure(iterableType.getTypeArguments().head); 3453 Type eType = tree.expr.type; 3454 while (eType.hasTag(TYPEVAR)) { 3455 eType = eType.getUpperBound(); 3456 } 3457 tree.expr.type = types.erasure(eType); 3458 if (eType.isCompound()) 3459 tree.expr = make.TypeCast(types.erasure(iterableType), tree.expr); 3460 Symbol iterator = lookupMethod(tree.expr.pos(), 3461 names.iterator, 3462 eType, 3463 List.<Type>nil()); 3464 VarSymbol itvar = new VarSymbol(SYNTHETIC, names.fromString("i" + target.syntheticNameChar()), 3465 types.erasure(types.asSuper(iterator.type.getReturnType(), syms.iteratorType.tsym)), 3466 currentMethodSym); 3467 3468 JCStatement init = make. 3469 VarDef(itvar, make.App(make.Select(tree.expr, iterator) 3470 .setType(types.erasure(iterator.type)))); 3471 3472 Symbol hasNext = lookupMethod(tree.expr.pos(), 3473 names.hasNext, 3474 itvar.type, 3475 List.<Type>nil()); 3476 JCMethodInvocation cond = make.App(make.Select(make.Ident(itvar), hasNext)); 3477 Symbol next = lookupMethod(tree.expr.pos(), 3478 names.next, 3479 itvar.type, 3480 List.<Type>nil()); 3481 JCExpression vardefinit = make.App(make.Select(make.Ident(itvar), next)); 3482 if (tree.var.type.isPrimitive()) 3483 vardefinit = make.TypeCast(types.cvarUpperBound(iteratorTarget), vardefinit); 3484 else 3485 vardefinit = make.TypeCast(tree.var.type, vardefinit); 3486 JCVariableDecl indexDef = (JCVariableDecl)make.VarDef(tree.var.mods, 3487 tree.var.name, 3488 tree.var.vartype, 3489 vardefinit).setType(tree.var.type); 3490 indexDef.sym = tree.var.sym; 3491 JCBlock body = make.Block(0, List.of(indexDef, tree.body)); 3492 body.endpos = TreeInfo.endPos(tree.body); 3493 result = translate(make. 3494 ForLoop(List.of(init), 3495 cond, 3496 List.<JCExpressionStatement>nil(), 3497 body)); 3498 patchTargets(body, tree, result); 3499 } 3500 3501 public void visitVarDef(JCVariableDecl tree) { 3502 MethodSymbol oldMethodSym = currentMethodSym; 3503 tree.mods = translate(tree.mods); 3504 tree.vartype = translate(tree.vartype); 3505 if (currentMethodSym == null) { 3506 // A class or instance field initializer. 3507 currentMethodSym = 3508 new MethodSymbol((tree.mods.flags&STATIC) | BLOCK, 3509 names.empty, null, 3510 currentClass); 3511 } 3512 if (tree.init != null) tree.init = translate(tree.init, tree.type); 3513 result = tree; 3514 currentMethodSym = oldMethodSym; 3515 } 3516 3517 public void visitBlock(JCBlock tree) { 3518 MethodSymbol oldMethodSym = currentMethodSym; 3519 if (currentMethodSym == null) { 3520 // Block is a static or instance initializer. 3521 currentMethodSym = 3522 new MethodSymbol(tree.flags | BLOCK, 3523 names.empty, null, 3524 currentClass); 3525 } 3526 super.visitBlock(tree); 3527 currentMethodSym = oldMethodSym; 3528 } 3529 3530 public void visitDoLoop(JCDoWhileLoop tree) { 3531 tree.body = translate(tree.body); 3532 tree.cond = translate(tree.cond, syms.booleanType); 3533 result = tree; 3534 } 3535 3536 public void visitWhileLoop(JCWhileLoop tree) { 3537 tree.cond = translate(tree.cond, syms.booleanType); 3538 tree.body = translate(tree.body); 3539 result = tree; 3540 } 3541 3542 public void visitForLoop(JCForLoop tree) { 3543 tree.init = translate(tree.init); 3544 if (tree.cond != null) 3545 tree.cond = translate(tree.cond, syms.booleanType); 3546 tree.step = translate(tree.step); 3547 tree.body = translate(tree.body); 3548 result = tree; 3549 } 3550 3551 public void visitReturn(JCReturn tree) { 3552 if (tree.expr != null) 3553 tree.expr = translate(tree.expr, 3554 types.erasure(currentMethodDef 3555 .restype.type)); 3556 result = tree; 3557 } 3558 3559 public void visitSwitch(JCSwitch tree) { 3560 Type selsuper = types.supertype(tree.selector.type); 3561 boolean enumSwitch = selsuper != null && 3562 (tree.selector.type.tsym.flags() & ENUM) != 0; 3563 boolean stringSwitch = selsuper != null && 3564 types.isSameType(tree.selector.type, syms.stringType); 3565 Type target = enumSwitch ? tree.selector.type : 3566 (stringSwitch? syms.stringType : syms.intType); 3567 tree.selector = translate(tree.selector, target); 3568 tree.cases = translateCases(tree.cases); 3569 if (enumSwitch) { 3570 result = visitEnumSwitch(tree); 3571 } else if (stringSwitch) { 3572 result = visitStringSwitch(tree); 3573 } else { 3574 result = tree; 3575 } 3576 } 3577 3578 public JCTree visitEnumSwitch(JCSwitch tree) { 3579 TypeSymbol enumSym = tree.selector.type.tsym; 3580 EnumMapping map = mapForEnum(tree.pos(), enumSym); 3581 make_at(tree.pos()); 3582 Symbol ordinalMethod = lookupMethod(tree.pos(), 3583 names.ordinal, 3584 tree.selector.type, 3585 List.<Type>nil()); 3586 JCArrayAccess selector = make.Indexed(map.mapVar, 3587 make.App(make.Select(tree.selector, 3588 ordinalMethod))); 3589 ListBuffer<JCCase> cases = new ListBuffer<>(); 3590 for (JCCase c : tree.cases) { 3591 if (c.pat != null) { 3592 VarSymbol label = (VarSymbol)TreeInfo.symbol(c.pat); 3593 JCLiteral pat = map.forConstant(label); 3594 cases.append(make.Case(pat, c.stats)); 3595 } else { 3596 cases.append(c); 3597 } 3598 } 3599 JCSwitch enumSwitch = make.Switch(selector, cases.toList()); 3600 patchTargets(enumSwitch, tree, enumSwitch); 3601 return enumSwitch; 3602 } 3603 3604 public JCTree visitStringSwitch(JCSwitch tree) { 3605 List<JCCase> caseList = tree.getCases(); 3606 int alternatives = caseList.size(); 3607 3608 if (alternatives == 0) { // Strange but legal possibility 3609 return make.at(tree.pos()).Exec(attr.makeNullCheck(tree.getExpression())); 3610 } else { 3611 /* 3612 * The general approach used is to translate a single 3613 * string switch statement into a series of two chained 3614 * switch statements: the first a synthesized statement 3615 * switching on the argument string's hash value and 3616 * computing a string's position in the list of original 3617 * case labels, if any, followed by a second switch on the 3618 * computed integer value. The second switch has the same 3619 * code structure as the original string switch statement 3620 * except that the string case labels are replaced with 3621 * positional integer constants starting at 0. 3622 * 3623 * The first switch statement can be thought of as an 3624 * inlined map from strings to their position in the case 3625 * label list. An alternate implementation would use an 3626 * actual Map for this purpose, as done for enum switches. 3627 * 3628 * With some additional effort, it would be possible to 3629 * use a single switch statement on the hash code of the 3630 * argument, but care would need to be taken to preserve 3631 * the proper control flow in the presence of hash 3632 * collisions and other complications, such as 3633 * fallthroughs. Switch statements with one or two 3634 * alternatives could also be specially translated into 3635 * if-then statements to omit the computation of the hash 3636 * code. 3637 * 3638 * The generated code assumes that the hashing algorithm 3639 * of String is the same in the compilation environment as 3640 * in the environment the code will run in. The string 3641 * hashing algorithm in the SE JDK has been unchanged 3642 * since at least JDK 1.2. Since the algorithm has been 3643 * specified since that release as well, it is very 3644 * unlikely to be changed in the future. 3645 * 3646 * Different hashing algorithms, such as the length of the 3647 * strings or a perfect hashing algorithm over the 3648 * particular set of case labels, could potentially be 3649 * used instead of String.hashCode. 3650 */ 3651 3652 ListBuffer<JCStatement> stmtList = new ListBuffer<>(); 3653 3654 // Map from String case labels to their original position in 3655 // the list of case labels. 3656 Map<String, Integer> caseLabelToPosition = new LinkedHashMap<>(alternatives + 1, 1.0f); 3657 3658 // Map of hash codes to the string case labels having that hashCode. 3659 Map<Integer, Set<String>> hashToString = new LinkedHashMap<>(alternatives + 1, 1.0f); 3660 3661 int casePosition = 0; 3662 for(JCCase oneCase : caseList) { 3663 JCExpression expression = oneCase.getExpression(); 3664 3665 if (expression != null) { // expression for a "default" case is null 3666 String labelExpr = (String) expression.type.constValue(); 3667 Integer mapping = caseLabelToPosition.put(labelExpr, casePosition); 3668 Assert.checkNull(mapping); 3669 int hashCode = labelExpr.hashCode(); 3670 3671 Set<String> stringSet = hashToString.get(hashCode); 3672 if (stringSet == null) { 3673 stringSet = new LinkedHashSet<>(1, 1.0f); 3674 stringSet.add(labelExpr); 3675 hashToString.put(hashCode, stringSet); 3676 } else { 3677 boolean added = stringSet.add(labelExpr); 3678 Assert.check(added); 3679 } 3680 } 3681 casePosition++; 3682 } 3683 3684 // Synthesize a switch statement that has the effect of 3685 // mapping from a string to the integer position of that 3686 // string in the list of case labels. This is done by 3687 // switching on the hashCode of the string followed by an 3688 // if-then-else chain comparing the input for equality 3689 // with all the case labels having that hash value. 3690 3691 /* 3692 * s$ = top of stack; 3693 * tmp$ = -1; 3694 * switch($s.hashCode()) { 3695 * case caseLabel.hashCode: 3696 * if (s$.equals("caseLabel_1") 3697 * tmp$ = caseLabelToPosition("caseLabel_1"); 3698 * else if (s$.equals("caseLabel_2")) 3699 * tmp$ = caseLabelToPosition("caseLabel_2"); 3700 * ... 3701 * break; 3702 * ... 3703 * } 3704 */ 3705 3706 VarSymbol dollar_s = new VarSymbol(FINAL|SYNTHETIC, 3707 names.fromString("s" + tree.pos + target.syntheticNameChar()), 3708 syms.stringType, 3709 currentMethodSym); 3710 stmtList.append(make.at(tree.pos()).VarDef(dollar_s, tree.getExpression()).setType(dollar_s.type)); 3711 3712 VarSymbol dollar_tmp = new VarSymbol(SYNTHETIC, 3713 names.fromString("tmp" + tree.pos + target.syntheticNameChar()), 3714 syms.intType, 3715 currentMethodSym); 3716 JCVariableDecl dollar_tmp_def = 3717 (JCVariableDecl)make.VarDef(dollar_tmp, make.Literal(INT, -1)).setType(dollar_tmp.type); 3718 dollar_tmp_def.init.type = dollar_tmp.type = syms.intType; 3719 stmtList.append(dollar_tmp_def); 3720 ListBuffer<JCCase> caseBuffer = new ListBuffer<>(); 3721 // hashCode will trigger nullcheck on original switch expression 3722 JCMethodInvocation hashCodeCall = makeCall(make.Ident(dollar_s), 3723 names.hashCode, 3724 List.<JCExpression>nil()).setType(syms.intType); 3725 JCSwitch switch1 = make.Switch(hashCodeCall, 3726 caseBuffer.toList()); 3727 for(Map.Entry<Integer, Set<String>> entry : hashToString.entrySet()) { 3728 int hashCode = entry.getKey(); 3729 Set<String> stringsWithHashCode = entry.getValue(); 3730 Assert.check(stringsWithHashCode.size() >= 1); 3731 3732 JCStatement elsepart = null; 3733 for(String caseLabel : stringsWithHashCode ) { 3734 JCMethodInvocation stringEqualsCall = makeCall(make.Ident(dollar_s), 3735 names.equals, 3736 List.<JCExpression>of(make.Literal(caseLabel))); 3737 elsepart = make.If(stringEqualsCall, 3738 make.Exec(make.Assign(make.Ident(dollar_tmp), 3739 make.Literal(caseLabelToPosition.get(caseLabel))). 3740 setType(dollar_tmp.type)), 3741 elsepart); 3742 } 3743 3744 ListBuffer<JCStatement> lb = new ListBuffer<>(); 3745 JCBreak breakStmt = make.Break(null); 3746 breakStmt.target = switch1; 3747 lb.append(elsepart).append(breakStmt); 3748 3749 caseBuffer.append(make.Case(make.Literal(hashCode), lb.toList())); 3750 } 3751 3752 switch1.cases = caseBuffer.toList(); 3753 stmtList.append(switch1); 3754 3755 // Make isomorphic switch tree replacing string labels 3756 // with corresponding integer ones from the label to 3757 // position map. 3758 3759 ListBuffer<JCCase> lb = new ListBuffer<>(); 3760 JCSwitch switch2 = make.Switch(make.Ident(dollar_tmp), lb.toList()); 3761 for(JCCase oneCase : caseList ) { 3762 // Rewire up old unlabeled break statements to the 3763 // replacement switch being created. 3764 patchTargets(oneCase, tree, switch2); 3765 3766 boolean isDefault = (oneCase.getExpression() == null); 3767 JCExpression caseExpr; 3768 if (isDefault) 3769 caseExpr = null; 3770 else { 3771 caseExpr = make.Literal(caseLabelToPosition.get((String)TreeInfo.skipParens(oneCase. 3772 getExpression()). 3773 type.constValue())); 3774 } 3775 3776 lb.append(make.Case(caseExpr, 3777 oneCase.getStatements())); 3778 } 3779 3780 switch2.cases = lb.toList(); 3781 stmtList.append(switch2); 3782 3783 return make.Block(0L, stmtList.toList()); 3784 } 3785 } 3786 3787 public void visitNewArray(JCNewArray tree) { 3788 tree.elemtype = translate(tree.elemtype); 3789 for (List<JCExpression> t = tree.dims; t.tail != null; t = t.tail) 3790 if (t.head != null) t.head = translate(t.head, syms.intType); 3791 tree.elems = translate(tree.elems, types.elemtype(tree.type)); 3792 result = tree; 3793 } 3794 3795 public void visitSelect(JCFieldAccess tree) { 3796 // need to special case-access of the form C.super.x 3797 // these will always need an access method, unless C 3798 // is a default interface subclassed by the current class. 3799 boolean qualifiedSuperAccess = 3800 tree.selected.hasTag(SELECT) && 3801 TreeInfo.name(tree.selected) == names._super && 3802 !types.isDirectSuperInterface(((JCFieldAccess)tree.selected).selected.type.tsym, currentClass); 3803 tree.selected = translate(tree.selected); 3804 if (tree.name == names._class) { 3805 result = classOf(tree.selected); 3806 } 3807 else if (tree.name == names._super && 3808 types.isDirectSuperInterface(tree.selected.type.tsym, currentClass)) { 3809 //default super call!! Not a classic qualified super call 3810 TypeSymbol supSym = tree.selected.type.tsym; 3811 Assert.checkNonNull(types.asSuper(currentClass.type, supSym)); 3812 result = tree; 3813 } 3814 else if (tree.name == names._this || tree.name == names._super) { 3815 result = makeThis(tree.pos(), tree.selected.type.tsym); 3816 } 3817 else 3818 result = access(tree.sym, tree, enclOp, qualifiedSuperAccess); 3819 } 3820 3821 public void visitLetExpr(LetExpr tree) { 3822 tree.defs = translateVarDefs(tree.defs); 3823 tree.expr = translate(tree.expr, tree.type); 3824 result = tree; 3825 } 3826 3827 // There ought to be nothing to rewrite here; 3828 // we don't generate code. 3829 public void visitAnnotation(JCAnnotation tree) { 3830 result = tree; 3831 } 3832 3833 @Override 3834 public void visitTry(JCTry tree) { 3835 if (tree.resources.nonEmpty()) { 3836 result = makeTwrTry(tree); 3837 return; 3838 } 3839 3840 boolean hasBody = tree.body.getStatements().nonEmpty(); 3841 boolean hasCatchers = tree.catchers.nonEmpty(); 3842 boolean hasFinally = tree.finalizer != null && 3843 tree.finalizer.getStatements().nonEmpty(); 3844 3845 if (!hasCatchers && !hasFinally) { 3846 result = translate(tree.body); 3847 return; 3848 } 3849 3850 if (!hasBody) { 3851 if (hasFinally) { 3852 result = translate(tree.finalizer); 3853 } else { 3854 result = translate(tree.body); 3855 } 3856 return; 3857 } 3858 3859 // no optimizations possible 3860 super.visitTry(tree); 3861 } 3862 3863/************************************************************************** 3864 * main method 3865 *************************************************************************/ 3866 3867 /** Translate a toplevel class and return a list consisting of 3868 * the translated class and translated versions of all inner classes. 3869 * @param env The attribution environment current at the class definition. 3870 * We need this for resolving some additional symbols. 3871 * @param cdef The tree representing the class definition. 3872 */ 3873 public List<JCTree> translateTopLevelClass(Env<AttrContext> env, JCTree cdef, TreeMaker make) { 3874 ListBuffer<JCTree> translated = null; 3875 try { 3876 attrEnv = env; 3877 this.make = make; 3878 endPosTable = env.toplevel.endPositions; 3879 currentClass = null; 3880 currentMethodDef = null; 3881 outermostClassDef = (cdef.hasTag(CLASSDEF)) ? (JCClassDecl)cdef : null; 3882 outermostMemberDef = null; 3883 this.translated = new ListBuffer<>(); 3884 classdefs = new HashMap<>(); 3885 actualSymbols = new HashMap<>(); 3886 freevarCache = new HashMap<>(); 3887 proxies = WriteableScope.create(syms.noSymbol); 3888 twrVars = WriteableScope.create(syms.noSymbol); 3889 outerThisStack = List.nil(); 3890 accessNums = new HashMap<>(); 3891 accessSyms = new HashMap<>(); 3892 accessConstrs = new HashMap<>(); 3893 accessConstrTags = List.nil(); 3894 accessed = new ListBuffer<>(); 3895 translate(cdef, (JCExpression)null); 3896 for (List<Symbol> l = accessed.toList(); l.nonEmpty(); l = l.tail) 3897 makeAccessible(l.head); 3898 for (EnumMapping map : enumSwitchMap.values()) 3899 map.translate(); 3900 checkConflicts(this.translated.toList()); 3901 checkAccessConstructorTags(); 3902 translated = this.translated; 3903 } finally { 3904 // note that recursive invocations of this method fail hard 3905 attrEnv = null; 3906 this.make = null; 3907 endPosTable = null; 3908 currentClass = null; 3909 currentMethodDef = null; 3910 outermostClassDef = null; 3911 outermostMemberDef = null; 3912 this.translated = null; 3913 classdefs = null; 3914 actualSymbols = null; 3915 freevarCache = null; 3916 proxies = null; 3917 outerThisStack = null; 3918 accessNums = null; 3919 accessSyms = null; 3920 accessConstrs = null; 3921 accessConstrTags = null; 3922 accessed = null; 3923 enumSwitchMap.clear(); 3924 assertionsDisabledClassCache = null; 3925 } 3926 return translated.toList(); 3927 } 3928} 3929