1 /* 2 * Copyright (c) 1999, 2022, Oracle and/or its affiliates. All rights reserved. 3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. 4 * 5 * This code is free software; you can redistribute it and/or modify it 6 * under the terms of the GNU General Public License version 2 only, as 7 * published by the Free Software Foundation. Oracle designates this 8 * particular file as subject to the "Classpath" exception as provided 9 * by Oracle in the LICENSE file that accompanied this code. 10 * 11 * This code is distributed in the hope that it will be useful, but WITHOUT 12 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or 13 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License 14 * version 2 for more details (a copy is included in the LICENSE file that 15 * accompanied this code). 16 * 17 * You should have received a copy of the GNU General Public License version 18 * 2 along with this work; if not, write to the Free Software Foundation, 19 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. 20 * 21 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA 22 * or visit www.oracle.com if you need additional information or have any 23 * questions. 24 */ 25 26 package com.sun.tools.javac.comp; 27 28 import java.util.*; 29 import java.util.stream.Collectors; 30 31 import com.sun.tools.javac.code.*; 32 import com.sun.tools.javac.code.Kinds.KindSelector; 33 import com.sun.tools.javac.code.Scope.WriteableScope; 34 import com.sun.tools.javac.jvm.*; 35 import com.sun.tools.javac.jvm.PoolConstant.LoadableConstant; 36 import com.sun.tools.javac.main.Option.PkgInfo; 37 import com.sun.tools.javac.resources.CompilerProperties.Fragments; 38 import com.sun.tools.javac.tree.*; 39 import com.sun.tools.javac.util.*; 40 import com.sun.tools.javac.util.JCDiagnostic.DiagnosticPosition; 41 import com.sun.tools.javac.util.List; 42 43 import com.sun.tools.javac.code.Symbol.*; 44 import com.sun.tools.javac.code.Symbol.OperatorSymbol.AccessCode; 45 import com.sun.tools.javac.resources.CompilerProperties.Errors; 46 import com.sun.tools.javac.tree.JCTree.*; 47 import com.sun.tools.javac.code.Type.*; 48 49 import com.sun.tools.javac.jvm.Target; 50 import com.sun.tools.javac.tree.EndPosTable; 51 52 import static com.sun.tools.javac.code.Flags.*; 53 import static com.sun.tools.javac.code.Flags.BLOCK; 54 import static com.sun.tools.javac.code.Scope.LookupKind.NON_RECURSIVE; 55 import static com.sun.tools.javac.code.TypeTag.*; 56 import static com.sun.tools.javac.code.Kinds.Kind.*; 57 import com.sun.tools.javac.code.Source.Feature; 58 import static com.sun.tools.javac.jvm.ByteCodes.*; 59 import com.sun.tools.javac.tree.JCTree.JCBreak; 60 import com.sun.tools.javac.tree.JCTree.JCCase; 61 import com.sun.tools.javac.tree.JCTree.JCExpression; 62 import com.sun.tools.javac.tree.JCTree.JCExpressionStatement; 63 import static com.sun.tools.javac.tree.JCTree.JCOperatorExpression.OperandPos.LEFT; 64 import com.sun.tools.javac.tree.JCTree.JCSwitchExpression; 65 import static com.sun.tools.javac.tree.JCTree.Tag.*; 66 67 /** This pass translates away some syntactic sugar: inner classes, 68 * class literals, assertions, foreach loops, etc. 69 * 70 * <p><b>This is NOT part of any supported API. 71 * If you write code that depends on this, you do so at your own risk. 72 * This code and its internal interfaces are subject to change or 73 * deletion without notice.</b> 74 */ 75 public class Lower extends TreeTranslator { 76 protected static final Context.Key<Lower> lowerKey = new Context.Key<>(); 77 78 public static Lower instance(Context context) { 79 Lower instance = context.get(lowerKey); 80 if (instance == null) 81 instance = new Lower(context); 82 return instance; 83 } 84 85 private final Names names; 86 private final Log log; 87 private final Symtab syms; 88 private final Resolve rs; 89 private final Operators operators; 90 private final Check chk; 91 private final Attr attr; 92 private TreeMaker make; 93 private DiagnosticPosition make_pos; 94 private final ConstFold cfolder; 95 private final Target target; 96 private final TypeEnvs typeEnvs; 97 private final Name dollarAssertionsDisabled; 98 private final Types types; 99 private final TransTypes transTypes; 100 private final boolean debugLower; 101 private final boolean disableProtectedAccessors; // experimental 102 private final PkgInfo pkginfoOpt; 103 private final boolean optimizeOuterThis; 104 private final boolean useMatchException; 105 106 @SuppressWarnings("this-escape") 107 protected Lower(Context context) { 108 context.put(lowerKey, this); 109 names = Names.instance(context); 110 log = Log.instance(context); 111 syms = Symtab.instance(context); 112 rs = Resolve.instance(context); 113 operators = Operators.instance(context); 114 chk = Check.instance(context); 115 attr = Attr.instance(context); 116 make = TreeMaker.instance(context); 117 cfolder = ConstFold.instance(context); 118 target = Target.instance(context); 119 typeEnvs = TypeEnvs.instance(context); 120 dollarAssertionsDisabled = names. 121 fromString(target.syntheticNameChar() + "assertionsDisabled"); 122 123 types = Types.instance(context); 124 transTypes = TransTypes.instance(context); 125 Options options = Options.instance(context); 126 debugLower = options.isSet("debuglower"); 127 pkginfoOpt = PkgInfo.get(options); 128 optimizeOuterThis = 129 target.optimizeOuterThis() || 130 options.getBoolean("optimizeOuterThis", false); 131 disableProtectedAccessors = options.isSet("disableProtectedAccessors"); 132 Source source = Source.instance(context); 133 Preview preview = Preview.instance(context); 134 useMatchException = Feature.PATTERN_SWITCH.allowedInSource(source) && 135 (preview.isEnabled() || !preview.isPreview(Feature.PATTERN_SWITCH)); 136 } 137 138 /** The currently enclosing class. 139 */ 140 ClassSymbol currentClass; 141 142 /** A queue of all translated classes. 143 */ 144 ListBuffer<JCTree> translated; 145 146 /** Environment for symbol lookup, set by translateTopLevelClass. 147 */ 148 Env<AttrContext> attrEnv; 149 150 /** A hash table mapping syntax trees to their ending source positions. 151 */ 152 EndPosTable endPosTable; 153 154 /************************************************************************** 155 * Global mappings 156 *************************************************************************/ 157 158 /** A hash table mapping local classes to their definitions. 159 */ 160 Map<ClassSymbol, JCClassDecl> classdefs; 161 162 /** A hash table mapping local classes to a list of pruned trees. 163 */ 164 public Map<ClassSymbol, List<JCTree>> prunedTree = new WeakHashMap<>(); 165 166 /** A hash table mapping virtual accessed symbols in outer subclasses 167 * to the actually referred symbol in superclasses. 168 */ 169 Map<Symbol,Symbol> actualSymbols; 170 171 /** The current method definition. 172 */ 173 JCMethodDecl currentMethodDef; 174 175 /** The current method symbol. 176 */ 177 MethodSymbol currentMethodSym; 178 179 /** The currently enclosing outermost class definition. 180 */ 181 JCClassDecl outermostClassDef; 182 183 /** The currently enclosing outermost member definition. 184 */ 185 JCTree outermostMemberDef; 186 187 /** A map from local variable symbols to their translation (as per LambdaToMethod). 188 * This is required when a capturing local class is created from a lambda (in which 189 * case the captured symbols should be replaced with the translated lambda symbols). 190 */ 191 Map<Symbol, Symbol> lambdaTranslationMap = null; 192 193 /** A navigator class for assembling a mapping from local class symbols 194 * to class definition trees. 195 * There is only one case; all other cases simply traverse down the tree. 196 */ 197 class ClassMap extends TreeScanner { 198 199 /** All encountered class defs are entered into classdefs table. 200 */ 201 public void visitClassDef(JCClassDecl tree) { 202 classdefs.put(tree.sym, tree); 203 super.visitClassDef(tree); 204 } 205 } 206 ClassMap classMap = new ClassMap(); 207 208 /** Map a class symbol to its definition. 209 * @param c The class symbol of which we want to determine the definition. 210 */ 211 JCClassDecl classDef(ClassSymbol c) { 212 // First lookup the class in the classdefs table. 213 JCClassDecl def = classdefs.get(c); 214 if (def == null && outermostMemberDef != null) { 215 // If this fails, traverse outermost member definition, entering all 216 // local classes into classdefs, and try again. 217 classMap.scan(outermostMemberDef); 218 def = classdefs.get(c); 219 } 220 if (def == null) { 221 // If this fails, traverse outermost class definition, entering all 222 // local classes into classdefs, and try again. 223 classMap.scan(outermostClassDef); 224 def = classdefs.get(c); 225 } 226 return def; 227 } 228 229 /** 230 * Get the enum constants for the given enum class symbol, if known. 231 * They will only be found if they are defined within the same top-level 232 * class as the class being compiled, so it's safe to assume that they 233 * can't change at runtime due to a recompilation. 234 */ 235 List<Name> enumNamesFor(ClassSymbol c) { 236 237 // Find the class definition and verify it is an enum class 238 final JCClassDecl classDef = classDef(c); 239 if (classDef == null || 240 (classDef.mods.flags & ENUM) == 0 || 241 (types.supertype(currentClass.type).tsym.flags() & ENUM) != 0) { 242 return null; 243 } 244 245 // Gather the enum identifiers 246 ListBuffer<Name> idents = new ListBuffer<>(); 247 for (List<JCTree> defs = classDef.defs; defs.nonEmpty(); defs=defs.tail) { 248 if (defs.head.hasTag(VARDEF) && 249 (((JCVariableDecl) defs.head).mods.flags & ENUM) != 0) { 250 JCVariableDecl var = (JCVariableDecl)defs.head; 251 idents.append(var.name); 252 } 253 } 254 return idents.toList(); 255 } 256 257 /** A hash table mapping class symbols to lists of free variables. 258 * accessed by them. Only free variables of the method immediately containing 259 * a class are associated with that class. 260 */ 261 Map<ClassSymbol,List<VarSymbol>> freevarCache; 262 263 /** A navigator class for collecting the free variables accessed 264 * from a local class. There is only one case; all other cases simply 265 * traverse down the tree. This class doesn't deal with the specific 266 * of Lower - it's an abstract visitor that is meant to be reused in 267 * order to share the local variable capture logic. 268 */ 269 abstract class BasicFreeVarCollector extends TreeScanner { 270 271 /** Add all free variables of class c to fvs list 272 * unless they are already there. 273 */ 274 abstract void addFreeVars(ClassSymbol c); 275 276 /** If tree refers to a variable in owner of local class, add it to 277 * free variables list. 278 */ 279 public void visitIdent(JCIdent tree) { 280 visitSymbol(tree.sym); 281 } 282 // where 283 abstract void visitSymbol(Symbol _sym); 284 285 /** If tree refers to a class instance creation expression 286 * add all free variables of the freshly created class. 287 */ 288 public void visitNewClass(JCNewClass tree) { 289 ClassSymbol c = (ClassSymbol)tree.constructor.owner; 290 addFreeVars(c); 291 super.visitNewClass(tree); 292 } 293 294 /** If tree refers to a superclass constructor call, 295 * add all free variables of the superclass. 296 */ 297 public void visitApply(JCMethodInvocation tree) { 298 if (TreeInfo.name(tree.meth) == names._super) { 299 addFreeVars((ClassSymbol) TreeInfo.symbol(tree.meth).owner); 300 } 301 super.visitApply(tree); 302 } 303 304 @Override 305 public void visitYield(JCYield tree) { 306 scan(tree.value); 307 } 308 309 } 310 311 /** 312 * Lower-specific subclass of {@code BasicFreeVarCollector}. 313 */ 314 class FreeVarCollector extends BasicFreeVarCollector { 315 316 /** The owner of the local class. 317 */ 318 Symbol owner; 319 320 /** The local class. 321 */ 322 ClassSymbol clazz; 323 324 /** The list of owner's variables accessed from within the local class, 325 * without any duplicates. 326 */ 327 List<VarSymbol> fvs; 328 329 FreeVarCollector(ClassSymbol clazz) { 330 this.clazz = clazz; 331 this.owner = clazz.owner; 332 this.fvs = List.nil(); 333 } 334 335 /** Add free variable to fvs list unless it is already there. 336 */ 337 private void addFreeVar(VarSymbol v) { 338 for (List<VarSymbol> l = fvs; l.nonEmpty(); l = l.tail) 339 if (l.head == v) return; 340 fvs = fvs.prepend(v); 341 } 342 343 @Override 344 void addFreeVars(ClassSymbol c) { 345 List<VarSymbol> fvs = freevarCache.get(c); 346 if (fvs != null) { 347 for (List<VarSymbol> l = fvs; l.nonEmpty(); l = l.tail) { 348 addFreeVar(l.head); 349 } 350 } 351 } 352 353 @Override 354 void visitSymbol(Symbol _sym) { 355 Symbol sym = _sym; 356 if (sym.kind == VAR || sym.kind == MTH) { 357 if (sym != null && sym.owner != owner) 358 sym = proxies.get(sym); 359 if (sym != null && sym.owner == owner) { 360 VarSymbol v = (VarSymbol)sym; 361 if (v.getConstValue() == null) { 362 addFreeVar(v); 363 } 364 } else { 365 if (outerThisStack.head != null && 366 outerThisStack.head != _sym) 367 visitSymbol(outerThisStack.head); 368 } 369 } 370 } 371 372 /** If tree refers to a class instance creation expression 373 * add all free variables of the freshly created class. 374 */ 375 public void visitNewClass(JCNewClass tree) { 376 ClassSymbol c = (ClassSymbol)tree.constructor.owner; 377 if (tree.encl == null && 378 c.hasOuterInstance() && 379 outerThisStack.head != null) 380 visitSymbol(outerThisStack.head); 381 super.visitNewClass(tree); 382 } 383 384 /** If tree refers to a qualified this or super expression 385 * for anything but the current class, add the outer this 386 * stack as a free variable. 387 */ 388 public void visitSelect(JCFieldAccess tree) { 389 if ((tree.name == names._this || tree.name == names._super) && 390 tree.selected.type.tsym != clazz && 391 outerThisStack.head != null) 392 visitSymbol(outerThisStack.head); 393 super.visitSelect(tree); 394 } 395 396 /** If tree refers to a superclass constructor call, 397 * add all free variables of the superclass. 398 */ 399 public void visitApply(JCMethodInvocation tree) { 400 if (TreeInfo.name(tree.meth) == names._super) { 401 Symbol constructor = TreeInfo.symbol(tree.meth); 402 ClassSymbol c = (ClassSymbol)constructor.owner; 403 if (c.hasOuterInstance() && 404 !tree.meth.hasTag(SELECT) && 405 outerThisStack.head != null) 406 visitSymbol(outerThisStack.head); 407 } 408 super.visitApply(tree); 409 } 410 411 } 412 413 ClassSymbol ownerToCopyFreeVarsFrom(ClassSymbol c) { 414 if (!c.isDirectlyOrIndirectlyLocal()) { 415 return null; 416 } 417 Symbol currentOwner = c.owner; 418 while (currentOwner.owner.kind.matches(KindSelector.TYP) && currentOwner.isDirectlyOrIndirectlyLocal()) { 419 currentOwner = currentOwner.owner; 420 } 421 if (currentOwner.owner.kind.matches(KindSelector.VAL_MTH) && c.isSubClass(currentOwner, types)) { 422 return (ClassSymbol)currentOwner; 423 } 424 return null; 425 } 426 427 /** Return the variables accessed from within a local class, which 428 * are declared in the local class' owner. 429 * (in reverse order of first access). 430 */ 431 List<VarSymbol> freevars(ClassSymbol c) { 432 List<VarSymbol> fvs = freevarCache.get(c); 433 if (fvs != null) { 434 return fvs; 435 } 436 if (c.owner.kind.matches(KindSelector.VAL_MTH) && !c.isStatic()) { 437 FreeVarCollector collector = new FreeVarCollector(c); 438 collector.scan(classDef(c)); 439 fvs = collector.fvs; 440 freevarCache.put(c, fvs); 441 return fvs; 442 } else { 443 ClassSymbol owner = ownerToCopyFreeVarsFrom(c); 444 if (owner != null) { 445 fvs = freevarCache.get(owner); 446 freevarCache.put(c, fvs); 447 return fvs; 448 } else { 449 return List.nil(); 450 } 451 } 452 } 453 454 Map<TypeSymbol,EnumMapping> enumSwitchMap = new LinkedHashMap<>(); 455 456 EnumMapping mapForEnum(DiagnosticPosition pos, TypeSymbol enumClass) { 457 458 // If enum class is part of this compilation, just switch on ordinal value 459 if (enumClass.kind == TYP) { 460 final List<Name> idents = enumNamesFor((ClassSymbol)enumClass); 461 if (idents != null) 462 return new CompileTimeEnumMapping(idents); 463 } 464 465 // Map identifiers to ordinal values at runtime, and then switch on that 466 return enumSwitchMap.computeIfAbsent(enumClass, ec -> new RuntimeEnumMapping(pos, ec)); 467 } 468 469 /** Generates a test value and corresponding cases for a switch on an enum type. 470 */ 471 interface EnumMapping { 472 473 /** Given an expression for the enum value's ordinal, generate an expression for the switch statement. 474 */ 475 JCExpression switchValue(JCExpression ordinalExpr); 476 477 /** Generate the switch statement case value corresponding to the given enum value. 478 */ 479 JCLiteral caseValue(VarSymbol v); 480 481 default void translate() { 482 } 483 } 484 485 /** EnumMapping using compile-time constants. Only valid when compiling the enum class itself, 486 * because otherwise the ordinals we use could become obsolete if/when the enum class is recompiled. 487 */ 488 class CompileTimeEnumMapping implements EnumMapping { 489 490 final List<Name> enumNames; 491 492 CompileTimeEnumMapping(List<Name> enumNames) { 493 Assert.check(enumNames != null); 494 this.enumNames = enumNames; 495 } 496 497 @Override 498 public JCExpression switchValue(JCExpression ordinalExpr) { 499 return ordinalExpr; 500 } 501 502 @Override 503 public JCLiteral caseValue(VarSymbol v) { 504 final int ordinal = enumNames.indexOf(v.name); 505 Assert.check(ordinal != -1); 506 return make.Literal(ordinal); 507 } 508 } 509 510 /** EnumMapping using run-time ordinal lookup. 511 * 512 * This builds a translation table to be used for enum switches. 513 * 514 * <p>For each enum that appears as the type of a switch 515 * expression, we maintain an EnumMapping to assist in the 516 * translation, as exemplified by the following example: 517 * 518 * <p>we translate 519 * <pre> 520 * switch(colorExpression) { 521 * case red: stmt1; 522 * case green: stmt2; 523 * } 524 * </pre> 525 * into 526 * <pre> 527 * switch(Outer$0.$EnumMap$Color[colorExpression.ordinal()]) { 528 * case 1: stmt1; 529 * case 2: stmt2 530 * } 531 * </pre> 532 * with the auxiliary table initialized as follows: 533 * <pre> 534 * class Outer$0 { 535 * synthetic final int[] $EnumMap$Color = new int[Color.values().length]; 536 * static { 537 * try { $EnumMap$Color[red.ordinal()] = 1; } catch (NoSuchFieldError ex) {} 538 * try { $EnumMap$Color[green.ordinal()] = 2; } catch (NoSuchFieldError ex) {} 539 * } 540 * } 541 * </pre> 542 * class EnumMapping provides mapping data and support methods for this translation. 543 */ 544 class RuntimeEnumMapping implements EnumMapping { 545 RuntimeEnumMapping(DiagnosticPosition pos, TypeSymbol forEnum) { 546 this.forEnum = forEnum; 547 this.values = new LinkedHashMap<>(); 548 this.pos = pos; 549 Name varName = names 550 .fromString(target.syntheticNameChar() + 551 "SwitchMap" + 552 target.syntheticNameChar() + 553 ClassWriter.externalize(forEnum.type.tsym.flatName().toString()) 554 .replace('/', '.') 555 .replace('.', target.syntheticNameChar())); 556 ClassSymbol outerCacheClass = outerCacheClass(); 557 this.mapVar = new VarSymbol(STATIC | SYNTHETIC | FINAL, 558 varName, 559 new ArrayType(syms.intType, syms.arrayClass), 560 outerCacheClass); 561 enterSynthetic(pos, mapVar, outerCacheClass.members()); 562 } 563 564 DiagnosticPosition pos = null; 565 566 // the next value to use 567 int next = 1; // 0 (unused map elements) go to the default label 568 569 // the enum for which this is a map 570 final TypeSymbol forEnum; 571 572 // the field containing the map 573 final VarSymbol mapVar; 574 575 // the mapped values 576 final Map<VarSymbol,Integer> values; 577 578 @Override 579 public JCExpression switchValue(JCExpression ordinalExpr) { 580 return make.Indexed(mapVar, ordinalExpr); 581 } 582 583 @Override 584 public JCLiteral caseValue(VarSymbol v) { 585 Integer result = values.get(v); 586 if (result == null) 587 values.put(v, result = next++); 588 return make.Literal(result); 589 } 590 591 // generate the field initializer for the map 592 @Override 593 public void translate() { 594 boolean prevAllowProtectedAccess = attrEnv.info.allowProtectedAccess; 595 try { 596 make.at(pos.getStartPosition()); 597 attrEnv.info.allowProtectedAccess = true; 598 JCClassDecl owner = classDef((ClassSymbol)mapVar.owner); 599 600 // synthetic static final int[] $SwitchMap$Color = new int[Color.values().length]; 601 MethodSymbol valuesMethod = lookupMethod(pos, 602 names.values, 603 forEnum.type, 604 List.nil()); 605 JCExpression size = make // Color.values().length 606 .Select(make.App(make.QualIdent(valuesMethod)), 607 syms.lengthVar); 608 JCExpression mapVarInit = make 609 .NewArray(make.Type(syms.intType), List.of(size), null) 610 .setType(new ArrayType(syms.intType, syms.arrayClass)); 611 612 // try { $SwitchMap$Color[red.ordinal()] = 1; } catch (java.lang.NoSuchFieldError ex) {} 613 ListBuffer<JCStatement> stmts = new ListBuffer<>(); 614 Symbol ordinalMethod = lookupMethod(pos, 615 names.ordinal, 616 forEnum.type, 617 List.nil()); 618 List<JCCatch> catcher = List.<JCCatch>nil() 619 .prepend(make.Catch(make.VarDef(new VarSymbol(PARAMETER, names.ex, 620 syms.noSuchFieldErrorType, 621 syms.noSymbol), 622 null), 623 make.Block(0, List.nil()))); 624 for (Map.Entry<VarSymbol,Integer> e : values.entrySet()) { 625 VarSymbol enumerator = e.getKey(); 626 Integer mappedValue = e.getValue(); 627 JCExpression assign = make 628 .Assign(make.Indexed(mapVar, 629 make.App(make.Select(make.QualIdent(enumerator), 630 ordinalMethod))), 631 make.Literal(mappedValue)) 632 .setType(syms.intType); 633 JCStatement exec = make.Exec(assign); 634 JCStatement _try = make.Try(make.Block(0, List.of(exec)), catcher, null); 635 stmts.append(_try); 636 } 637 638 owner.defs = owner.defs 639 .prepend(make.Block(STATIC, stmts.toList())) 640 .prepend(make.VarDef(mapVar, mapVarInit)); 641 } finally { 642 attrEnv.info.allowProtectedAccess = prevAllowProtectedAccess; 643 } 644 } 645 } 646 647 648 /************************************************************************** 649 * Tree building blocks 650 *************************************************************************/ 651 652 /** Equivalent to make.at(pos.getStartPosition()) with side effect of caching 653 * pos as make_pos, for use in diagnostics. 654 **/ 655 TreeMaker make_at(DiagnosticPosition pos) { 656 make_pos = pos; 657 return make.at(pos); 658 } 659 660 /** Make an attributed tree representing a literal. This will be an 661 * Ident node in the case of boolean literals, a Literal node in all 662 * other cases. 663 * @param type The literal's type. 664 * @param value The literal's value. 665 */ 666 JCExpression makeLit(Type type, Object value) { 667 return make.Literal(type.getTag(), value).setType(type.constType(value)); 668 } 669 670 /** Make an attributed tree representing null. 671 */ 672 JCExpression makeNull() { 673 return makeLit(syms.botType, null); 674 } 675 676 /** Make an attributed class instance creation expression. 677 * @param ctype The class type. 678 * @param args The constructor arguments. 679 */ 680 JCNewClass makeNewClass(Type ctype, List<JCExpression> args) { 681 JCNewClass tree = make.NewClass(null, 682 null, make.QualIdent(ctype.tsym), args, null); 683 tree.constructor = rs.resolveConstructor( 684 make_pos, attrEnv, ctype, TreeInfo.types(args), List.nil()); 685 tree.type = ctype; 686 return tree; 687 } 688 689 /** Make an attributed unary expression. 690 * @param optag The operators tree tag. 691 * @param arg The operator's argument. 692 */ 693 JCUnary makeUnary(JCTree.Tag optag, JCExpression arg) { 694 JCUnary tree = make.Unary(optag, arg); 695 tree.operator = operators.resolveUnary(tree, optag, arg.type); 696 tree.type = tree.operator.type.getReturnType(); 697 return tree; 698 } 699 700 /** Make an attributed binary expression. 701 * @param optag The operators tree tag. 702 * @param lhs The operator's left argument. 703 * @param rhs The operator's right argument. 704 */ 705 JCBinary makeBinary(JCTree.Tag optag, JCExpression lhs, JCExpression rhs) { 706 JCBinary tree = make.Binary(optag, lhs, rhs); 707 tree.operator = operators.resolveBinary(tree, optag, lhs.type, rhs.type); 708 tree.type = tree.operator.type.getReturnType(); 709 return tree; 710 } 711 712 /** Make an attributed assignop expression. 713 * @param optag The operators tree tag. 714 * @param lhs The operator's left argument. 715 * @param rhs The operator's right argument. 716 */ 717 JCAssignOp makeAssignop(JCTree.Tag optag, JCTree lhs, JCTree rhs) { 718 JCAssignOp tree = make.Assignop(optag, lhs, rhs); 719 tree.operator = operators.resolveBinary(tree, tree.getTag().noAssignOp(), lhs.type, rhs.type); 720 tree.type = lhs.type; 721 return tree; 722 } 723 724 /** Convert tree into string object, unless it has already a 725 * reference type.. 726 */ 727 JCExpression makeString(JCExpression tree) { 728 if (!tree.type.isPrimitiveOrVoid()) { 729 return tree; 730 } else { 731 Symbol valueOfSym = lookupMethod(tree.pos(), 732 names.valueOf, 733 syms.stringType, 734 List.of(tree.type)); 735 return make.App(make.QualIdent(valueOfSym), List.of(tree)); 736 } 737 } 738 739 /** Create an empty anonymous class definition and enter and complete 740 * its symbol. Return the class definition's symbol. 741 * and create 742 * @param flags The class symbol's flags 743 * @param owner The class symbol's owner 744 */ 745 JCClassDecl makeEmptyClass(long flags, ClassSymbol owner) { 746 return makeEmptyClass(flags, owner, null, true); 747 } 748 749 JCClassDecl makeEmptyClass(long flags, ClassSymbol owner, Name flatname, 750 boolean addToDefs) { 751 // Create class symbol. 752 ClassSymbol c = syms.defineClass(names.empty, owner); 753 if (flatname != null) { 754 c.flatname = flatname; 755 } else { 756 c.flatname = chk.localClassName(c); 757 } 758 c.sourcefile = owner.sourcefile; 759 c.completer = Completer.NULL_COMPLETER; 760 c.members_field = WriteableScope.create(c); 761 c.flags_field = flags; 762 ClassType ctype = (ClassType) c.type; 763 ctype.supertype_field = syms.objectType; 764 ctype.interfaces_field = List.nil(); 765 766 JCClassDecl odef = classDef(owner); 767 768 // Enter class symbol in owner scope and compiled table. 769 enterSynthetic(odef.pos(), c, owner.members()); 770 chk.putCompiled(c); 771 772 // Create class definition tree. 773 JCClassDecl cdef = make.ClassDef( 774 make.Modifiers(flags), names.empty, 775 List.nil(), 776 null, List.nil(), List.nil()); 777 cdef.sym = c; 778 cdef.type = c.type; 779 780 // Append class definition tree to owner's definitions. 781 if (addToDefs) odef.defs = odef.defs.prepend(cdef); 782 return cdef; 783 } 784 785 /************************************************************************** 786 * Symbol manipulation utilities 787 *************************************************************************/ 788 789 /** Enter a synthetic symbol in a given scope, but complain if there was already one there. 790 * @param pos Position for error reporting. 791 * @param sym The symbol. 792 * @param s The scope. 793 */ 794 private void enterSynthetic(DiagnosticPosition pos, Symbol sym, WriteableScope s) { 795 s.enter(sym); 796 } 797 798 /** Create a fresh synthetic name within a given scope - the unique name is 799 * obtained by appending '$' chars at the end of the name until no match 800 * is found. 801 * 802 * @param name base name 803 * @param s scope in which the name has to be unique 804 * @return fresh synthetic name 805 */ 806 private Name makeSyntheticName(Name name, Scope s) { 807 do { 808 name = name.append( 809 target.syntheticNameChar(), 810 names.empty); 811 } while (lookupSynthetic(name, s) != null); 812 return name; 813 } 814 815 /** Check whether synthetic symbols generated during lowering conflict 816 * with user-defined symbols. 817 * 818 * @param translatedTrees lowered class trees 819 */ 820 void checkConflicts(List<JCTree> translatedTrees) { 821 for (JCTree t : translatedTrees) { 822 t.accept(conflictsChecker); 823 } 824 } 825 826 JCTree.Visitor conflictsChecker = new TreeScanner() { 827 828 TypeSymbol currentClass; 829 830 @Override 831 public void visitMethodDef(JCMethodDecl that) { 832 checkConflicts(that.pos(), that.sym, currentClass); 833 super.visitMethodDef(that); 834 } 835 836 @Override 837 public void visitVarDef(JCVariableDecl that) { 838 if (that.sym.owner.kind == TYP) { 839 checkConflicts(that.pos(), that.sym, currentClass); 840 } 841 super.visitVarDef(that); 842 } 843 844 @Override 845 public void visitClassDef(JCClassDecl that) { 846 TypeSymbol prevCurrentClass = currentClass; 847 currentClass = that.sym; 848 try { 849 super.visitClassDef(that); 850 } 851 finally { 852 currentClass = prevCurrentClass; 853 } 854 } 855 856 void checkConflicts(DiagnosticPosition pos, Symbol sym, TypeSymbol c) { 857 for (Type ct = c.type; ct != Type.noType ; ct = types.supertype(ct)) { 858 for (Symbol sym2 : ct.tsym.members().getSymbolsByName(sym.name, NON_RECURSIVE)) { 859 // VM allows methods and variables with differing types 860 if (sym.kind == sym2.kind && 861 types.isSameType(types.erasure(sym.type), types.erasure(sym2.type)) && 862 sym != sym2 && 863 (sym.flags() & Flags.SYNTHETIC) != (sym2.flags() & Flags.SYNTHETIC) && 864 (sym.flags() & BRIDGE) == 0 && (sym2.flags() & BRIDGE) == 0) { 865 syntheticError(pos, (sym2.flags() & SYNTHETIC) == 0 ? sym2 : sym); 866 return; 867 } 868 } 869 } 870 } 871 872 /** Report a conflict between a user symbol and a synthetic symbol. 873 */ 874 private void syntheticError(DiagnosticPosition pos, Symbol sym) { 875 if (!sym.type.isErroneous()) { 876 log.error(pos, Errors.CannotGenerateClass(sym.location(), Fragments.SyntheticNameConflict(sym, sym.location()))); 877 } 878 } 879 }; 880 881 /** Look up a synthetic name in a given scope. 882 * @param s The scope. 883 * @param name The name. 884 */ 885 private Symbol lookupSynthetic(Name name, Scope s) { 886 Symbol sym = s.findFirst(name); 887 return (sym==null || (sym.flags()&SYNTHETIC)==0) ? null : sym; 888 } 889 890 /** Look up a method in a given scope. 891 */ 892 private MethodSymbol lookupMethod(DiagnosticPosition pos, Name name, Type qual, List<Type> args) { 893 return rs.resolveInternalMethod(pos, attrEnv, qual, name, args, List.nil()); 894 } 895 896 /** Anon inner classes are used as access constructor tags. 897 * accessConstructorTag will use an existing anon class if one is available, 898 * and synthesize a class (with makeEmptyClass) if one is not available. 899 * However, there is a small possibility that an existing class will not 900 * be generated as expected if it is inside a conditional with a constant 901 * expression. If that is found to be the case, create an empty class tree here. 902 */ 903 private void checkAccessConstructorTags() { 904 for (List<ClassSymbol> l = accessConstrTags; l.nonEmpty(); l = l.tail) { 905 ClassSymbol c = l.head; 906 if (isTranslatedClassAvailable(c)) 907 continue; 908 // Create class definition tree. 909 JCClassDecl cdec = makeEmptyClass(STATIC | SYNTHETIC, 910 c.outermostClass(), c.flatname, false); 911 swapAccessConstructorTag(c, cdec.sym); 912 translated.append(cdec); 913 } 914 } 915 // where 916 private boolean isTranslatedClassAvailable(ClassSymbol c) { 917 for (JCTree tree: translated) { 918 if (tree.hasTag(CLASSDEF) 919 && ((JCClassDecl) tree).sym == c) { 920 return true; 921 } 922 } 923 return false; 924 } 925 926 void swapAccessConstructorTag(ClassSymbol oldCTag, ClassSymbol newCTag) { 927 for (MethodSymbol methodSymbol : accessConstrs.values()) { 928 Assert.check(methodSymbol.type.hasTag(METHOD)); 929 MethodType oldMethodType = 930 (MethodType)methodSymbol.type; 931 if (oldMethodType.argtypes.head.tsym == oldCTag) 932 methodSymbol.type = 933 types.createMethodTypeWithParameters(oldMethodType, 934 oldMethodType.getParameterTypes().tail 935 .prepend(newCTag.erasure(types))); 936 } 937 } 938 939 /************************************************************************** 940 * Access methods 941 *************************************************************************/ 942 943 /** A mapping from symbols to their access numbers. 944 */ 945 private Map<Symbol,Integer> accessNums; 946 947 /** A mapping from symbols to an array of access symbols, indexed by 948 * access code. 949 */ 950 private Map<Symbol,MethodSymbol[]> accessSyms; 951 952 /** A mapping from (constructor) symbols to access constructor symbols. 953 */ 954 private Map<Symbol,MethodSymbol> accessConstrs; 955 956 /** A list of all class symbols used for access constructor tags. 957 */ 958 private List<ClassSymbol> accessConstrTags; 959 960 /** A queue for all accessed symbols. 961 */ 962 private ListBuffer<Symbol> accessed; 963 964 /** return access code for identifier, 965 * @param tree The tree representing the identifier use. 966 * @param enclOp The closest enclosing operation node of tree, 967 * null if tree is not a subtree of an operation. 968 */ 969 private static int accessCode(JCTree tree, JCTree enclOp) { 970 if (enclOp == null) 971 return AccessCode.DEREF.code; 972 else if (enclOp.hasTag(ASSIGN) && 973 tree == TreeInfo.skipParens(((JCAssign) enclOp).lhs)) 974 return AccessCode.ASSIGN.code; 975 else if ((enclOp.getTag().isIncOrDecUnaryOp() || enclOp.getTag().isAssignop()) && 976 tree == TreeInfo.skipParens(((JCOperatorExpression) enclOp).getOperand(LEFT))) 977 return (((JCOperatorExpression) enclOp).operator).getAccessCode(enclOp.getTag()); 978 else 979 return AccessCode.DEREF.code; 980 } 981 982 /** Return binary operator that corresponds to given access code. 983 */ 984 private OperatorSymbol binaryAccessOperator(int acode, Tag tag) { 985 return operators.lookupBinaryOp(op -> op.getAccessCode(tag) == acode); 986 } 987 988 /** Return tree tag for assignment operation corresponding 989 * to given binary operator. 990 */ 991 private static JCTree.Tag treeTag(OperatorSymbol operator) { 992 switch (operator.opcode) { 993 case ByteCodes.ior: case ByteCodes.lor: 994 return BITOR_ASG; 995 case ByteCodes.ixor: case ByteCodes.lxor: 996 return BITXOR_ASG; 997 case ByteCodes.iand: case ByteCodes.land: 998 return BITAND_ASG; 999 case ByteCodes.ishl: case ByteCodes.lshl: 1000 case ByteCodes.ishll: case ByteCodes.lshll: 1001 return SL_ASG; 1002 case ByteCodes.ishr: case ByteCodes.lshr: 1003 case ByteCodes.ishrl: case ByteCodes.lshrl: 1004 return SR_ASG; 1005 case ByteCodes.iushr: case ByteCodes.lushr: 1006 case ByteCodes.iushrl: case ByteCodes.lushrl: 1007 return USR_ASG; 1008 case ByteCodes.iadd: case ByteCodes.ladd: 1009 case ByteCodes.fadd: case ByteCodes.dadd: 1010 case ByteCodes.string_add: 1011 return PLUS_ASG; 1012 case ByteCodes.isub: case ByteCodes.lsub: 1013 case ByteCodes.fsub: case ByteCodes.dsub: 1014 return MINUS_ASG; 1015 case ByteCodes.imul: case ByteCodes.lmul: 1016 case ByteCodes.fmul: case ByteCodes.dmul: 1017 return MUL_ASG; 1018 case ByteCodes.idiv: case ByteCodes.ldiv: 1019 case ByteCodes.fdiv: case ByteCodes.ddiv: 1020 return DIV_ASG; 1021 case ByteCodes.imod: case ByteCodes.lmod: 1022 case ByteCodes.fmod: case ByteCodes.dmod: 1023 return MOD_ASG; 1024 default: 1025 throw new AssertionError(); 1026 } 1027 } 1028 1029 /** The name of the access method with number `anum' and access code `acode'. 1030 */ 1031 Name accessName(int anum, int acode) { 1032 return names.fromString( 1033 "access" + target.syntheticNameChar() + anum + acode / 10 + acode % 10); 1034 } 1035 1036 /** Return access symbol for a private or protected symbol from an inner class. 1037 * @param sym The accessed private symbol. 1038 * @param tree The accessing tree. 1039 * @param enclOp The closest enclosing operation node of tree, 1040 * null if tree is not a subtree of an operation. 1041 * @param protAccess Is access to a protected symbol in another 1042 * package? 1043 * @param refSuper Is access via a (qualified) C.super? 1044 */ 1045 MethodSymbol accessSymbol(Symbol sym, JCTree tree, JCTree enclOp, 1046 boolean protAccess, boolean refSuper) { 1047 ClassSymbol accOwner = refSuper && protAccess 1048 // For access via qualified super (T.super.x), place the 1049 // access symbol on T. 1050 ? (ClassSymbol)((JCFieldAccess) tree).selected.type.tsym 1051 // Otherwise pretend that the owner of an accessed 1052 // protected symbol is the enclosing class of the current 1053 // class which is a subclass of the symbol's owner. 1054 : accessClass(sym, protAccess, tree); 1055 1056 Symbol vsym = sym; 1057 if (sym.owner != accOwner) { 1058 vsym = sym.clone(accOwner); 1059 actualSymbols.put(vsym, sym); 1060 } 1061 1062 Integer anum // The access number of the access method. 1063 = accessNums.get(vsym); 1064 if (anum == null) { 1065 anum = accessed.length(); 1066 accessNums.put(vsym, anum); 1067 accessSyms.put(vsym, new MethodSymbol[AccessCode.numberOfAccessCodes]); 1068 accessed.append(vsym); 1069 // System.out.println("accessing " + vsym + " in " + vsym.location()); 1070 } 1071 1072 int acode; // The access code of the access method. 1073 List<Type> argtypes; // The argument types of the access method. 1074 Type restype; // The result type of the access method. 1075 List<Type> thrown; // The thrown exceptions of the access method. 1076 switch (vsym.kind) { 1077 case VAR: 1078 acode = accessCode(tree, enclOp); 1079 if (acode >= AccessCode.FIRSTASGOP.code) { 1080 OperatorSymbol operator = binaryAccessOperator(acode, enclOp.getTag()); 1081 if (operator.opcode == string_add) 1082 argtypes = List.of(syms.objectType); 1083 else 1084 argtypes = operator.type.getParameterTypes().tail; 1085 } else if (acode == AccessCode.ASSIGN.code) 1086 argtypes = List.of(vsym.erasure(types)); 1087 else 1088 argtypes = List.nil(); 1089 restype = vsym.erasure(types); 1090 thrown = List.nil(); 1091 break; 1092 case MTH: 1093 acode = AccessCode.DEREF.code; 1094 argtypes = vsym.erasure(types).getParameterTypes(); 1095 restype = vsym.erasure(types).getReturnType(); 1096 thrown = vsym.type.getThrownTypes(); 1097 break; 1098 default: 1099 throw new AssertionError(); 1100 } 1101 1102 // For references via qualified super, increment acode by one, 1103 // making it odd. 1104 if (protAccess && refSuper) acode++; 1105 1106 // Instance access methods get instance as first parameter. 1107 // For protected symbols this needs to be the instance as a member 1108 // of the type containing the accessed symbol, not the class 1109 // containing the access method. 1110 if ((vsym.flags() & STATIC) == 0) { 1111 argtypes = argtypes.prepend(vsym.owner.erasure(types)); 1112 } 1113 MethodSymbol[] accessors = accessSyms.get(vsym); 1114 MethodSymbol accessor = accessors[acode]; 1115 if (accessor == null) { 1116 accessor = new MethodSymbol( 1117 STATIC | SYNTHETIC | (accOwner.isInterface() ? PUBLIC : 0), 1118 accessName(anum.intValue(), acode), 1119 new MethodType(argtypes, restype, thrown, syms.methodClass), 1120 accOwner); 1121 enterSynthetic(tree.pos(), accessor, accOwner.members()); 1122 accessors[acode] = accessor; 1123 } 1124 return accessor; 1125 } 1126 1127 /** The qualifier to be used for accessing a symbol in an outer class. 1128 * This is either C.sym or C.this.sym, depending on whether or not 1129 * sym is static. 1130 * @param sym The accessed symbol. 1131 */ 1132 JCExpression accessBase(DiagnosticPosition pos, Symbol sym) { 1133 return (sym.flags() & STATIC) != 0 1134 ? access(make.at(pos.getStartPosition()).QualIdent(sym.owner)) 1135 : makeOwnerThis(pos, sym, true); 1136 } 1137 1138 /** Do we need an access method to reference private symbol? 1139 */ 1140 boolean needsPrivateAccess(Symbol sym) { 1141 if (target.hasNestmateAccess()) { 1142 return false; 1143 } 1144 if ((sym.flags() & PRIVATE) == 0 || sym.owner == currentClass) { 1145 return false; 1146 } else if (sym.name == names.init && sym.owner.isDirectlyOrIndirectlyLocal()) { 1147 // private constructor in local class: relax protection 1148 sym.flags_field &= ~PRIVATE; 1149 return false; 1150 } else { 1151 return true; 1152 } 1153 } 1154 1155 /** Do we need an access method to reference symbol in other package? 1156 */ 1157 boolean needsProtectedAccess(Symbol sym, JCTree tree) { 1158 if (disableProtectedAccessors) return false; 1159 if ((sym.flags() & PROTECTED) == 0 || 1160 sym.owner.owner == currentClass.owner || // fast special case 1161 sym.packge() == currentClass.packge()) 1162 return false; 1163 if (!currentClass.isSubClass(sym.owner, types)) 1164 return true; 1165 if ((sym.flags() & STATIC) != 0 || 1166 !tree.hasTag(SELECT) || 1167 TreeInfo.name(((JCFieldAccess) tree).selected) == names._super) 1168 return false; 1169 return !((JCFieldAccess) tree).selected.type.tsym.isSubClass(currentClass, types); 1170 } 1171 1172 /** The class in which an access method for given symbol goes. 1173 * @param sym The access symbol 1174 * @param protAccess Is access to a protected symbol in another 1175 * package? 1176 */ 1177 ClassSymbol accessClass(Symbol sym, boolean protAccess, JCTree tree) { 1178 if (protAccess) { 1179 Symbol qualifier = null; 1180 ClassSymbol c = currentClass; 1181 if (tree.hasTag(SELECT) && (sym.flags() & STATIC) == 0) { 1182 qualifier = ((JCFieldAccess) tree).selected.type.tsym; 1183 while (!qualifier.isSubClass(c, types)) { 1184 c = c.owner.enclClass(); 1185 } 1186 return c; 1187 } else { 1188 while (!c.isSubClass(sym.owner, types)) { 1189 c = c.owner.enclClass(); 1190 } 1191 } 1192 return c; 1193 } else { 1194 // the symbol is private 1195 return sym.owner.enclClass(); 1196 } 1197 } 1198 1199 private void addPrunedInfo(JCTree tree) { 1200 List<JCTree> infoList = prunedTree.get(currentClass); 1201 infoList = (infoList == null) ? List.of(tree) : infoList.prepend(tree); 1202 prunedTree.put(currentClass, infoList); 1203 } 1204 1205 /** Ensure that identifier is accessible, return tree accessing the identifier. 1206 * @param sym The accessed symbol. 1207 * @param tree The tree referring to the symbol. 1208 * @param enclOp The closest enclosing operation node of tree, 1209 * null if tree is not a subtree of an operation. 1210 * @param refSuper Is access via a (qualified) C.super? 1211 */ 1212 JCExpression access(Symbol sym, JCExpression tree, JCExpression enclOp, boolean refSuper) { 1213 // Access a free variable via its proxy, or its proxy's proxy 1214 while (sym.kind == VAR && sym.owner.kind == MTH && 1215 sym.owner.enclClass() != currentClass) { 1216 // A constant is replaced by its constant value. 1217 Object cv = ((VarSymbol)sym).getConstValue(); 1218 if (cv != null) { 1219 make.at(tree.pos); 1220 return makeLit(sym.type, cv); 1221 } 1222 if (lambdaTranslationMap != null && lambdaTranslationMap.get(sym) != null) { 1223 return make.at(tree.pos).Ident(lambdaTranslationMap.get(sym)); 1224 } else { 1225 // Otherwise replace the variable by its proxy. 1226 sym = proxies.get(sym); 1227 Assert.check(sym != null && (sym.flags_field & FINAL) != 0); 1228 tree = make.at(tree.pos).Ident(sym); 1229 } 1230 } 1231 JCExpression base = (tree.hasTag(SELECT)) ? ((JCFieldAccess) tree).selected : null; 1232 switch (sym.kind) { 1233 case TYP: 1234 if (sym.owner.kind != PCK) { 1235 // Convert type idents to 1236 // <flat name> or <package name> . <flat name> 1237 Name flatname = Convert.shortName(sym.flatName()); 1238 while (base != null && 1239 TreeInfo.symbol(base) != null && 1240 TreeInfo.symbol(base).kind != PCK) { 1241 base = (base.hasTag(SELECT)) 1242 ? ((JCFieldAccess) base).selected 1243 : null; 1244 } 1245 if (tree.hasTag(IDENT)) { 1246 ((JCIdent) tree).name = flatname; 1247 } else if (base == null) { 1248 tree = make.at(tree.pos).Ident(sym); 1249 ((JCIdent) tree).name = flatname; 1250 } else { 1251 ((JCFieldAccess) tree).selected = base; 1252 ((JCFieldAccess) tree).name = flatname; 1253 } 1254 } 1255 break; 1256 case MTH: case VAR: 1257 if (sym.owner.kind == TYP) { 1258 1259 // Access methods are required for 1260 // - private members, 1261 // - protected members in a superclass of an 1262 // enclosing class contained in another package. 1263 // - all non-private members accessed via a qualified super. 1264 boolean protAccess = refSuper && !needsPrivateAccess(sym) 1265 || needsProtectedAccess(sym, tree); 1266 boolean accReq = protAccess || needsPrivateAccess(sym); 1267 1268 // A base has to be supplied for 1269 // - simple identifiers accessing variables in outer classes. 1270 boolean baseReq = 1271 base == null && 1272 sym.owner != syms.predefClass && 1273 !sym.isMemberOf(currentClass, types); 1274 1275 if (accReq || baseReq) { 1276 make.at(tree.pos); 1277 1278 // Constants are replaced by their constant value. 1279 if (sym.kind == VAR) { 1280 Object cv = ((VarSymbol)sym).getConstValue(); 1281 if (cv != null) { 1282 addPrunedInfo(tree); 1283 return makeLit(sym.type, cv); 1284 } 1285 } 1286 1287 // Private variables and methods are replaced by calls 1288 // to their access methods. 1289 if (accReq) { 1290 List<JCExpression> args = List.nil(); 1291 if ((sym.flags() & STATIC) == 0) { 1292 // Instance access methods get instance 1293 // as first parameter. 1294 if (base == null) 1295 base = makeOwnerThis(tree.pos(), sym, true); 1296 args = args.prepend(base); 1297 base = null; // so we don't duplicate code 1298 } 1299 Symbol access = accessSymbol(sym, tree, 1300 enclOp, protAccess, 1301 refSuper); 1302 JCExpression receiver = make.Select( 1303 base != null ? base : make.QualIdent(access.owner), 1304 access); 1305 return make.App(receiver, args); 1306 1307 // Other accesses to members of outer classes get a 1308 // qualifier. 1309 } else if (baseReq) { 1310 return make.at(tree.pos).Select( 1311 accessBase(tree.pos(), sym), sym).setType(tree.type); 1312 } 1313 } 1314 } else if (sym.owner.kind == MTH && lambdaTranslationMap != null) { 1315 //sym is a local variable - check the lambda translation map to 1316 //see if sym has been translated to something else in the current 1317 //scope (by LambdaToMethod) 1318 Symbol translatedSym = lambdaTranslationMap.get(sym.baseSymbol()); 1319 if (translatedSym != null) { 1320 tree = make.at(tree.pos).Ident(translatedSym); 1321 } 1322 } 1323 } 1324 return tree; 1325 } 1326 1327 /** Ensure that identifier is accessible, return tree accessing the identifier. 1328 * @param tree The identifier tree. 1329 */ 1330 JCExpression access(JCExpression tree) { 1331 Symbol sym = TreeInfo.symbol(tree); 1332 return sym == null ? tree : access(sym, tree, null, false); 1333 } 1334 1335 /** Return access constructor for a private constructor, 1336 * or the constructor itself, if no access constructor is needed. 1337 * @param pos The position to report diagnostics, if any. 1338 * @param constr The private constructor. 1339 */ 1340 Symbol accessConstructor(DiagnosticPosition pos, Symbol constr) { 1341 if (needsPrivateAccess(constr)) { 1342 ClassSymbol accOwner = constr.owner.enclClass(); 1343 MethodSymbol aconstr = accessConstrs.get(constr); 1344 if (aconstr == null) { 1345 List<Type> argtypes = constr.type.getParameterTypes(); 1346 if ((accOwner.flags_field & ENUM) != 0) 1347 argtypes = argtypes 1348 .prepend(syms.intType) 1349 .prepend(syms.stringType); 1350 aconstr = new MethodSymbol( 1351 SYNTHETIC, 1352 names.init, 1353 new MethodType( 1354 argtypes.append( 1355 accessConstructorTag().erasure(types)), 1356 constr.type.getReturnType(), 1357 constr.type.getThrownTypes(), 1358 syms.methodClass), 1359 accOwner); 1360 enterSynthetic(pos, aconstr, accOwner.members()); 1361 accessConstrs.put(constr, aconstr); 1362 accessed.append(constr); 1363 } 1364 return aconstr; 1365 } else { 1366 return constr; 1367 } 1368 } 1369 1370 /** Return an anonymous class nested in this toplevel class. 1371 */ 1372 ClassSymbol accessConstructorTag() { 1373 ClassSymbol topClass = currentClass.outermostClass(); 1374 ModuleSymbol topModle = topClass.packge().modle; 1375 for (int i = 1; ; i++) { 1376 Name flatname = names.fromString("" + topClass.getQualifiedName() + 1377 target.syntheticNameChar() + 1378 i); 1379 ClassSymbol ctag = chk.getCompiled(topModle, flatname); 1380 if (ctag == null) 1381 ctag = makeEmptyClass(STATIC | SYNTHETIC, topClass).sym; 1382 else if (!ctag.isAnonymous()) 1383 continue; 1384 // keep a record of all tags, to verify that all are generated as required 1385 accessConstrTags = accessConstrTags.prepend(ctag); 1386 return ctag; 1387 } 1388 } 1389 1390 /** Add all required access methods for a private symbol to enclosing class. 1391 * @param sym The symbol. 1392 */ 1393 void makeAccessible(Symbol sym) { 1394 JCClassDecl cdef = classDef(sym.owner.enclClass()); 1395 if (cdef == null) Assert.error("class def not found: " + sym + " in " + sym.owner); 1396 if (sym.name == names.init) { 1397 cdef.defs = cdef.defs.prepend( 1398 accessConstructorDef(cdef.pos, sym, accessConstrs.get(sym))); 1399 } else { 1400 MethodSymbol[] accessors = accessSyms.get(sym); 1401 for (int i = 0; i < AccessCode.numberOfAccessCodes; i++) { 1402 if (accessors[i] != null) 1403 cdef.defs = cdef.defs.prepend( 1404 accessDef(cdef.pos, sym, accessors[i], i)); 1405 } 1406 } 1407 } 1408 1409 /** Construct definition of an access method. 1410 * @param pos The source code position of the definition. 1411 * @param vsym The private or protected symbol. 1412 * @param accessor The access method for the symbol. 1413 * @param acode The access code. 1414 */ 1415 JCTree accessDef(int pos, Symbol vsym, MethodSymbol accessor, int acode) { 1416 // System.err.println("access " + vsym + " with " + accessor);//DEBUG 1417 currentClass = vsym.owner.enclClass(); 1418 make.at(pos); 1419 JCMethodDecl md = make.MethodDef(accessor, null); 1420 1421 // Find actual symbol 1422 Symbol sym = actualSymbols.get(vsym); 1423 if (sym == null) sym = vsym; 1424 1425 JCExpression ref; // The tree referencing the private symbol. 1426 List<JCExpression> args; // Any additional arguments to be passed along. 1427 if ((sym.flags() & STATIC) != 0) { 1428 ref = make.Ident(sym); 1429 args = make.Idents(md.params); 1430 } else { 1431 JCExpression site = make.Ident(md.params.head); 1432 if (acode % 2 != 0) { 1433 //odd access codes represent qualified super accesses - need to 1434 //emit reference to the direct superclass, even if the referred 1435 //member is from an indirect superclass (JLS 13.1) 1436 site.setType(types.erasure(types.supertype(vsym.owner.enclClass().type))); 1437 } 1438 ref = make.Select(site, sym); 1439 args = make.Idents(md.params.tail); 1440 } 1441 JCStatement stat; // The statement accessing the private symbol. 1442 if (sym.kind == VAR) { 1443 // Normalize out all odd access codes by taking floor modulo 2: 1444 int acode1 = acode - (acode & 1); 1445 1446 JCExpression expr; // The access method's return value. 1447 AccessCode aCode = AccessCode.getFromCode(acode1); 1448 switch (aCode) { 1449 case DEREF: 1450 expr = ref; 1451 break; 1452 case ASSIGN: 1453 expr = make.Assign(ref, args.head); 1454 break; 1455 case PREINC: case POSTINC: case PREDEC: case POSTDEC: 1456 expr = makeUnary(aCode.tag, ref); 1457 break; 1458 default: 1459 expr = make.Assignop( 1460 treeTag(binaryAccessOperator(acode1, JCTree.Tag.NO_TAG)), ref, args.head); 1461 ((JCAssignOp) expr).operator = binaryAccessOperator(acode1, JCTree.Tag.NO_TAG); 1462 } 1463 stat = make.Return(expr.setType(sym.type)); 1464 } else { 1465 stat = make.Call(make.App(ref, args)); 1466 } 1467 md.body = make.Block(0, List.of(stat)); 1468 1469 // Make sure all parameters, result types and thrown exceptions 1470 // are accessible. 1471 for (List<JCVariableDecl> l = md.params; l.nonEmpty(); l = l.tail) 1472 l.head.vartype = access(l.head.vartype); 1473 md.restype = access(md.restype); 1474 for (List<JCExpression> l = md.thrown; l.nonEmpty(); l = l.tail) 1475 l.head = access(l.head); 1476 1477 return md; 1478 } 1479 1480 /** Construct definition of an access constructor. 1481 * @param pos The source code position of the definition. 1482 * @param constr The private constructor. 1483 * @param accessor The access method for the constructor. 1484 */ 1485 JCTree accessConstructorDef(int pos, Symbol constr, MethodSymbol accessor) { 1486 make.at(pos); 1487 JCMethodDecl md = make.MethodDef(accessor, 1488 accessor.externalType(types), 1489 null); 1490 JCIdent callee = make.Ident(names._this); 1491 callee.sym = constr; 1492 callee.type = constr.type; 1493 md.body = 1494 make.Block(0, List.of( 1495 make.Call( 1496 make.App( 1497 callee, 1498 make.Idents(md.params.reverse().tail.reverse()))))); 1499 return md; 1500 } 1501 1502 /************************************************************************** 1503 * Free variables proxies and this$n 1504 *************************************************************************/ 1505 1506 /** A map which allows to retrieve the translated proxy variable for any given symbol of an 1507 * enclosing scope that is accessed (the accessed symbol could be the synthetic 'this$n' symbol). 1508 * Inside a constructor, the map temporarily overrides entries corresponding to proxies and any 1509 * 'this$n' symbols, where they represent the constructor parameters. 1510 */ 1511 Map<Symbol, Symbol> proxies; 1512 1513 /** A scope containing all unnamed resource variables/saved 1514 * exception variables for translated TWR blocks 1515 */ 1516 WriteableScope twrVars; 1517 1518 /** A stack containing the this$n field of the currently translated 1519 * classes (if needed) in innermost first order. 1520 * Inside a constructor, proxies and any this$n symbol are duplicated 1521 * in an additional innermost scope, where they represent the constructor 1522 * parameters. 1523 */ 1524 List<VarSymbol> outerThisStack; 1525 1526 /** The name of a free variable proxy. 1527 */ 1528 Name proxyName(Name name, int index) { 1529 Name proxyName = names.fromString("val" + target.syntheticNameChar() + name); 1530 if (index > 0) { 1531 proxyName = proxyName.append(names.fromString("" + target.syntheticNameChar() + index)); 1532 } 1533 return proxyName; 1534 } 1535 1536 /** Proxy definitions for all free variables in given list, in reverse order. 1537 * @param pos The source code position of the definition. 1538 * @param freevars The free variables. 1539 * @param owner The class in which the definitions go. 1540 */ 1541 List<JCVariableDecl> freevarDefs(int pos, List<VarSymbol> freevars, Symbol owner) { 1542 return freevarDefs(pos, freevars, owner, 0); 1543 } 1544 1545 List<JCVariableDecl> freevarDefs(int pos, List<VarSymbol> freevars, Symbol owner, 1546 long additionalFlags) { 1547 long flags = FINAL | SYNTHETIC | additionalFlags; 1548 List<JCVariableDecl> defs = List.nil(); 1549 Set<Name> proxyNames = new HashSet<>(); 1550 for (List<VarSymbol> l = freevars; l.nonEmpty(); l = l.tail) { 1551 VarSymbol v = l.head; 1552 int index = 0; 1553 Name proxyName; 1554 do { 1555 proxyName = proxyName(v.name, index++); 1556 } while (!proxyNames.add(proxyName)); 1557 VarSymbol proxy = new VarSymbol( 1558 flags, proxyName, v.erasure(types), owner); 1559 proxies.put(v, proxy); 1560 JCVariableDecl vd = make.at(pos).VarDef(proxy, null); 1561 vd.vartype = access(vd.vartype); 1562 defs = defs.prepend(vd); 1563 } 1564 return defs; 1565 } 1566 1567 /** The name of a this$n field 1568 * @param type The class referenced by the this$n field 1569 */ 1570 Name outerThisName(Type type, Symbol owner) { 1571 Type t = type.getEnclosingType(); 1572 int nestingLevel = 0; 1573 while (t.hasTag(CLASS)) { 1574 t = t.getEnclosingType(); 1575 nestingLevel++; 1576 } 1577 Name result = names.fromString("this" + target.syntheticNameChar() + nestingLevel); 1578 while (owner.kind == TYP && ((ClassSymbol)owner).members().findFirst(result) != null) 1579 result = names.fromString(result.toString() + target.syntheticNameChar()); 1580 return result; 1581 } 1582 1583 private VarSymbol makeOuterThisVarSymbol(Symbol owner, long flags) { 1584 Type target = types.erasure(owner.enclClass().type.getEnclosingType()); 1585 // Set NOOUTERTHIS for all synthetic outer instance variables, and unset 1586 // it when the variable is accessed. If the variable is never accessed, 1587 // we skip creating an outer instance field and saving the constructor 1588 // parameter to it. 1589 VarSymbol outerThis = 1590 new VarSymbol(flags | NOOUTERTHIS, outerThisName(target, owner), target, owner); 1591 outerThisStack = outerThisStack.prepend(outerThis); 1592 return outerThis; 1593 } 1594 1595 private JCVariableDecl makeOuterThisVarDecl(int pos, VarSymbol sym) { 1596 JCVariableDecl vd = make.at(pos).VarDef(sym, null); 1597 vd.vartype = access(vd.vartype); 1598 return vd; 1599 } 1600 1601 /** Definition for this$n field. 1602 * @param pos The source code position of the definition. 1603 * @param owner The method in which the definition goes. 1604 */ 1605 JCVariableDecl outerThisDef(int pos, MethodSymbol owner) { 1606 ClassSymbol c = owner.enclClass(); 1607 boolean isMandated = 1608 // Anonymous constructors 1609 (owner.isConstructor() && owner.isAnonymous()) || 1610 // Constructors of non-private inner member classes 1611 (owner.isConstructor() && c.isInner() && 1612 !c.isPrivate() && !c.isStatic()); 1613 long flags = 1614 FINAL | (isMandated ? MANDATED : SYNTHETIC) | PARAMETER; 1615 VarSymbol outerThis = makeOuterThisVarSymbol(owner, flags); 1616 owner.extraParams = owner.extraParams.prepend(outerThis); 1617 return makeOuterThisVarDecl(pos, outerThis); 1618 } 1619 1620 /** Definition for this$n field. 1621 * @param pos The source code position of the definition. 1622 * @param owner The class in which the definition goes. 1623 */ 1624 JCVariableDecl outerThisDef(int pos, ClassSymbol owner) { 1625 VarSymbol outerThis = makeOuterThisVarSymbol(owner, FINAL | SYNTHETIC); 1626 return makeOuterThisVarDecl(pos, outerThis); 1627 } 1628 1629 /** Return a list of trees that load the free variables in given list, 1630 * in reverse order. 1631 * @param pos The source code position to be used for the trees. 1632 * @param freevars The list of free variables. 1633 */ 1634 List<JCExpression> loadFreevars(DiagnosticPosition pos, List<VarSymbol> freevars) { 1635 List<JCExpression> args = List.nil(); 1636 for (List<VarSymbol> l = freevars; l.nonEmpty(); l = l.tail) 1637 args = args.prepend(loadFreevar(pos, l.head)); 1638 return args; 1639 } 1640 //where 1641 JCExpression loadFreevar(DiagnosticPosition pos, VarSymbol v) { 1642 return access(v, make.at(pos).Ident(v), null, false); 1643 } 1644 1645 /** Construct a tree simulating the expression {@code C.this}. 1646 * @param pos The source code position to be used for the tree. 1647 * @param c The qualifier class. 1648 */ 1649 JCExpression makeThis(DiagnosticPosition pos, TypeSymbol c) { 1650 if (currentClass == c) { 1651 // in this case, `this' works fine 1652 return make.at(pos).This(c.erasure(types)); 1653 } else { 1654 // need to go via this$n 1655 return makeOuterThis(pos, c); 1656 } 1657 } 1658 1659 /** 1660 * Optionally replace a try statement with the desugaring of a 1661 * try-with-resources statement. The canonical desugaring of 1662 * 1663 * try ResourceSpecification 1664 * Block 1665 * 1666 * is 1667 * 1668 * { 1669 * final VariableModifiers_minus_final R #resource = Expression; 1670 * 1671 * try ResourceSpecificationtail 1672 * Block 1673 * } body-only-finally { 1674 * if (#resource != null) //nullcheck skipped if Expression is provably non-null 1675 * #resource.close(); 1676 * } catch (Throwable #primaryException) { 1677 * if (#resource != null) //nullcheck skipped if Expression is provably non-null 1678 * try { 1679 * #resource.close(); 1680 * } catch (Throwable #suppressedException) { 1681 * #primaryException.addSuppressed(#suppressedException); 1682 * } 1683 * throw #primaryException; 1684 * } 1685 * } 1686 * 1687 * @param tree The try statement to inspect. 1688 * @return a desugared try-with-resources tree, or the original 1689 * try block if there are no resources to manage. 1690 */ 1691 JCTree makeTwrTry(JCTry tree) { 1692 make_at(tree.pos()); 1693 twrVars = twrVars.dup(); 1694 JCBlock twrBlock = makeTwrBlock(tree.resources, tree.body, 0); 1695 if (tree.catchers.isEmpty() && tree.finalizer == null) 1696 result = translate(twrBlock); 1697 else 1698 result = translate(make.Try(twrBlock, tree.catchers, tree.finalizer)); 1699 twrVars = twrVars.leave(); 1700 return result; 1701 } 1702 1703 private JCBlock makeTwrBlock(List<JCTree> resources, JCBlock block, int depth) { 1704 if (resources.isEmpty()) 1705 return block; 1706 1707 // Add resource declaration or expression to block statements 1708 ListBuffer<JCStatement> stats = new ListBuffer<>(); 1709 JCTree resource = resources.head; 1710 JCExpression resourceUse; 1711 boolean resourceNonNull; 1712 if (resource instanceof JCVariableDecl variableDecl) { 1713 resourceUse = make.Ident(variableDecl.sym).setType(resource.type); 1714 resourceNonNull = variableDecl.init != null && TreeInfo.skipParens(variableDecl.init).hasTag(NEWCLASS); 1715 stats.add(variableDecl); 1716 } else { 1717 Assert.check(resource instanceof JCExpression); 1718 VarSymbol syntheticTwrVar = 1719 new VarSymbol(SYNTHETIC | FINAL, 1720 makeSyntheticName(names.fromString("twrVar" + 1721 depth), twrVars), 1722 (resource.type.hasTag(BOT)) ? 1723 syms.autoCloseableType : resource.type, 1724 currentMethodSym); 1725 twrVars.enter(syntheticTwrVar); 1726 JCVariableDecl syntheticTwrVarDecl = 1727 make.VarDef(syntheticTwrVar, (JCExpression)resource); 1728 resourceUse = (JCExpression)make.Ident(syntheticTwrVar); 1729 resourceNonNull = false; 1730 stats.add(syntheticTwrVarDecl); 1731 } 1732 1733 //create (semi-) finally block that will be copied into the main try body: 1734 int oldPos = make.pos; 1735 make.at(TreeInfo.endPos(block)); 1736 1737 // if (#resource != null) { #resource.close(); } 1738 JCStatement bodyCloseStatement = makeResourceCloseInvocation(resourceUse); 1739 1740 if (!resourceNonNull) { 1741 bodyCloseStatement = make.If(makeNonNullCheck(resourceUse), 1742 bodyCloseStatement, 1743 null); 1744 } 1745 1746 JCBlock finallyClause = make.Block(BODY_ONLY_FINALIZE, List.of(bodyCloseStatement)); 1747 make.at(oldPos); 1748 1749 // Create catch clause that saves exception, closes the resource and then rethrows the exception: 1750 VarSymbol primaryException = 1751 new VarSymbol(FINAL|SYNTHETIC, 1752 names.fromString("t" + 1753 target.syntheticNameChar()), 1754 syms.throwableType, 1755 currentMethodSym); 1756 JCVariableDecl primaryExceptionDecl = make.VarDef(primaryException, null); 1757 1758 // close resource: 1759 // try { 1760 // #resource.close(); 1761 // } catch (Throwable #suppressedException) { 1762 // #primaryException.addSuppressed(#suppressedException); 1763 // } 1764 VarSymbol suppressedException = 1765 new VarSymbol(SYNTHETIC, make.paramName(2), 1766 syms.throwableType, 1767 currentMethodSym); 1768 JCStatement addSuppressedStatement = 1769 make.Exec(makeCall(make.Ident(primaryException), 1770 names.addSuppressed, 1771 List.of(make.Ident(suppressedException)))); 1772 JCBlock closeResourceTryBlock = 1773 make.Block(0L, List.of(makeResourceCloseInvocation(resourceUse))); 1774 JCVariableDecl catchSuppressedDecl = make.VarDef(suppressedException, null); 1775 JCBlock catchSuppressedBlock = make.Block(0L, List.of(addSuppressedStatement)); 1776 List<JCCatch> catchSuppressedClauses = 1777 List.of(make.Catch(catchSuppressedDecl, catchSuppressedBlock)); 1778 JCTry closeResourceTry = make.Try(closeResourceTryBlock, catchSuppressedClauses, null); 1779 closeResourceTry.finallyCanCompleteNormally = true; 1780 1781 JCStatement exceptionalCloseStatement = closeResourceTry; 1782 1783 if (!resourceNonNull) { 1784 // if (#resource != null) { } 1785 exceptionalCloseStatement = make.If(makeNonNullCheck(resourceUse), 1786 exceptionalCloseStatement, 1787 null); 1788 } 1789 1790 JCStatement exceptionalRethrow = make.Throw(make.Ident(primaryException)); 1791 JCBlock exceptionalCloseBlock = make.Block(0L, List.of(exceptionalCloseStatement, exceptionalRethrow)); 1792 JCCatch exceptionalCatchClause = make.Catch(primaryExceptionDecl, exceptionalCloseBlock); 1793 1794 //create the main try statement with the close: 1795 JCTry outerTry = make.Try(makeTwrBlock(resources.tail, block, depth + 1), 1796 List.of(exceptionalCatchClause), 1797 finallyClause); 1798 1799 outerTry.finallyCanCompleteNormally = true; 1800 stats.add(outerTry); 1801 1802 JCBlock newBlock = make.Block(0L, stats.toList()); 1803 return newBlock; 1804 } 1805 1806 private JCStatement makeResourceCloseInvocation(JCExpression resource) { 1807 // convert to AutoCloseable if needed 1808 if (types.asSuper(resource.type, syms.autoCloseableType.tsym) == null) { 1809 resource = convert(resource, syms.autoCloseableType); 1810 } 1811 1812 // create resource.close() method invocation 1813 JCExpression resourceClose = makeCall(resource, 1814 names.close, 1815 List.nil()); 1816 return make.Exec(resourceClose); 1817 } 1818 1819 private JCExpression makeNonNullCheck(JCExpression expression) { 1820 return makeBinary(NE, expression, makeNull()); 1821 } 1822 1823 /** Construct a tree that represents the outer instance 1824 * {@code C.this}. Never pick the current `this'. 1825 * @param pos The source code position to be used for the tree. 1826 * @param c The qualifier class. 1827 */ 1828 JCExpression makeOuterThis(DiagnosticPosition pos, TypeSymbol c) { 1829 List<VarSymbol> ots = outerThisStack; 1830 if (ots.isEmpty()) { 1831 log.error(pos, Errors.NoEnclInstanceOfTypeInScope(c)); 1832 Assert.error(); 1833 return makeNull(); 1834 } 1835 VarSymbol ot = ots.head; 1836 JCExpression tree = access(make.at(pos).Ident(ot)); 1837 ot.flags_field &= ~NOOUTERTHIS; 1838 TypeSymbol otc = ot.type.tsym; 1839 while (otc != c) { 1840 do { 1841 ots = ots.tail; 1842 if (ots.isEmpty()) { 1843 log.error(pos, Errors.NoEnclInstanceOfTypeInScope(c)); 1844 Assert.error(); // should have been caught in Attr 1845 return tree; 1846 } 1847 ot = ots.head; 1848 } while (ot.owner != otc); 1849 if (otc.owner.kind != PCK && !otc.hasOuterInstance()) { 1850 chk.earlyRefError(pos, c); 1851 Assert.error(); // should have been caught in Attr 1852 return makeNull(); 1853 } 1854 tree = access(make.at(pos).Select(tree, ot)); 1855 ot.flags_field &= ~NOOUTERTHIS; 1856 otc = ot.type.tsym; 1857 } 1858 return tree; 1859 } 1860 1861 /** Construct a tree that represents the closest outer instance 1862 * {@code C.this} such that the given symbol is a member of C. 1863 * @param pos The source code position to be used for the tree. 1864 * @param sym The accessed symbol. 1865 * @param preciseMatch should we accept a type that is a subtype of 1866 * sym's owner, even if it doesn't contain sym 1867 * due to hiding, overriding, or non-inheritance 1868 * due to protection? 1869 */ 1870 JCExpression makeOwnerThis(DiagnosticPosition pos, Symbol sym, boolean preciseMatch) { 1871 Symbol c = sym.owner; 1872 if (preciseMatch ? sym.isMemberOf(currentClass, types) 1873 : currentClass.isSubClass(sym.owner, types)) { 1874 // in this case, `this' works fine 1875 return make.at(pos).This(c.erasure(types)); 1876 } else { 1877 // need to go via this$n 1878 return makeOwnerThisN(pos, sym, preciseMatch); 1879 } 1880 } 1881 1882 /** 1883 * Similar to makeOwnerThis but will never pick "this". 1884 */ 1885 JCExpression makeOwnerThisN(DiagnosticPosition pos, Symbol sym, boolean preciseMatch) { 1886 Symbol c = sym.owner; 1887 List<VarSymbol> ots = outerThisStack; 1888 if (ots.isEmpty()) { 1889 log.error(pos, Errors.NoEnclInstanceOfTypeInScope(c)); 1890 Assert.error(); 1891 return makeNull(); 1892 } 1893 VarSymbol ot = ots.head; 1894 JCExpression tree = access(make.at(pos).Ident(ot)); 1895 ot.flags_field &= ~NOOUTERTHIS; 1896 TypeSymbol otc = ot.type.tsym; 1897 while (!(preciseMatch ? sym.isMemberOf(otc, types) : otc.isSubClass(sym.owner, types))) { 1898 do { 1899 ots = ots.tail; 1900 if (ots.isEmpty()) { 1901 log.error(pos, Errors.NoEnclInstanceOfTypeInScope(c)); 1902 Assert.error(); 1903 return tree; 1904 } 1905 ot = ots.head; 1906 } while (ot.owner != otc); 1907 tree = access(make.at(pos).Select(tree, ot)); 1908 ot.flags_field &= ~NOOUTERTHIS; 1909 otc = ot.type.tsym; 1910 } 1911 return tree; 1912 } 1913 1914 /** Return tree simulating the assignment {@code this.name = name}, where 1915 * name is the name of a free variable. 1916 */ 1917 JCStatement initField(int pos, Symbol rhs, Symbol lhs) { 1918 Assert.check(rhs.owner.kind == MTH); 1919 Assert.check(rhs.owner.owner == lhs.owner); 1920 make.at(pos); 1921 return 1922 make.Exec( 1923 make.Assign( 1924 make.Select(make.This(lhs.owner.erasure(types)), lhs), 1925 make.Ident(rhs)).setType(lhs.erasure(types))); 1926 } 1927 1928 /** Return tree simulating the assignment {@code this.this$n = this$n}. 1929 */ 1930 JCStatement initOuterThis(int pos, VarSymbol rhs) { 1931 Assert.check(rhs.owner.kind == MTH); 1932 VarSymbol lhs = outerThisStack.head; 1933 Assert.check(rhs.owner.owner == lhs.owner); 1934 make.at(pos); 1935 return 1936 make.Exec( 1937 make.Assign( 1938 make.Select(make.This(lhs.owner.erasure(types)), lhs), 1939 make.Ident(rhs)).setType(lhs.erasure(types))); 1940 } 1941 1942 /************************************************************************** 1943 * Code for .class 1944 *************************************************************************/ 1945 1946 /** Return the symbol of a class to contain a cache of 1947 * compiler-generated statics such as class$ and the 1948 * $assertionsDisabled flag. We create an anonymous nested class 1949 * (unless one already exists) and return its symbol. However, 1950 * for backward compatibility in 1.4 and earlier we use the 1951 * top-level class itself. 1952 */ 1953 private ClassSymbol outerCacheClass() { 1954 ClassSymbol clazz = outermostClassDef.sym; 1955 Scope s = clazz.members(); 1956 for (Symbol sym : s.getSymbols(NON_RECURSIVE)) 1957 if (sym.kind == TYP && 1958 sym.name == names.empty && 1959 (sym.flags() & INTERFACE) == 0) return (ClassSymbol) sym; 1960 return makeEmptyClass(STATIC | SYNTHETIC, clazz).sym; 1961 } 1962 1963 /** Create an attributed tree of the form left.name(). */ 1964 private JCMethodInvocation makeCall(JCExpression left, Name name, List<JCExpression> args) { 1965 Assert.checkNonNull(left.type); 1966 Symbol funcsym = lookupMethod(make_pos, name, left.type, 1967 TreeInfo.types(args)); 1968 return make.App(make.Select(left, funcsym), args); 1969 } 1970 1971 /** The tree simulating a T.class expression. 1972 * @param clazz The tree identifying type T. 1973 */ 1974 private JCExpression classOf(JCTree clazz) { 1975 return classOfType(clazz.type, clazz.pos()); 1976 } 1977 1978 private JCExpression classOfType(Type type, DiagnosticPosition pos) { 1979 switch (type.getTag()) { 1980 case BYTE: case SHORT: case CHAR: case INT: case LONG: case FLOAT: 1981 case DOUBLE: case BOOLEAN: case VOID: 1982 // replace with <BoxedClass>.TYPE 1983 ClassSymbol c = types.boxedClass(type); 1984 Symbol typeSym = 1985 rs.accessBase( 1986 rs.findIdentInType(pos, attrEnv, c.type, names.TYPE, KindSelector.VAR), 1987 pos, c.type, names.TYPE, true); 1988 if (typeSym.kind == VAR) 1989 ((VarSymbol)typeSym).getConstValue(); // ensure initializer is evaluated 1990 return make.QualIdent(typeSym); 1991 case CLASS: case ARRAY: 1992 VarSymbol sym = new VarSymbol( 1993 STATIC | PUBLIC | FINAL, names._class, 1994 syms.classType, type.tsym); 1995 return make_at(pos).Select(make.Type(type), sym); 1996 default: 1997 throw new AssertionError(); 1998 } 1999 } 2000 2001 /************************************************************************** 2002 * Code for enabling/disabling assertions. 2003 *************************************************************************/ 2004 2005 private ClassSymbol assertionsDisabledClassCache; 2006 2007 /**Used to create an auxiliary class to hold $assertionsDisabled for interfaces. 2008 */ 2009 private ClassSymbol assertionsDisabledClass() { 2010 if (assertionsDisabledClassCache != null) return assertionsDisabledClassCache; 2011 2012 assertionsDisabledClassCache = makeEmptyClass(STATIC | SYNTHETIC, outermostClassDef.sym).sym; 2013 2014 return assertionsDisabledClassCache; 2015 } 2016 2017 // This code is not particularly robust if the user has 2018 // previously declared a member named '$assertionsDisabled'. 2019 // The same faulty idiom also appears in the translation of 2020 // class literals above. We should report an error if a 2021 // previous declaration is not synthetic. 2022 2023 private JCExpression assertFlagTest(DiagnosticPosition pos) { 2024 // Outermost class may be either true class or an interface. 2025 ClassSymbol outermostClass = outermostClassDef.sym; 2026 2027 //only classes can hold a non-public field, look for a usable one: 2028 ClassSymbol container = !currentClass.isInterface() ? currentClass : 2029 assertionsDisabledClass(); 2030 2031 VarSymbol assertDisabledSym = 2032 (VarSymbol)lookupSynthetic(dollarAssertionsDisabled, 2033 container.members()); 2034 if (assertDisabledSym == null) { 2035 assertDisabledSym = 2036 new VarSymbol(STATIC | FINAL | SYNTHETIC, 2037 dollarAssertionsDisabled, 2038 syms.booleanType, 2039 container); 2040 enterSynthetic(pos, assertDisabledSym, container.members()); 2041 Symbol desiredAssertionStatusSym = lookupMethod(pos, 2042 names.desiredAssertionStatus, 2043 types.erasure(syms.classType), 2044 List.nil()); 2045 JCClassDecl containerDef = classDef(container); 2046 make_at(containerDef.pos()); 2047 JCExpression notStatus = makeUnary(NOT, make.App(make.Select( 2048 classOfType(types.erasure(outermostClass.type), 2049 containerDef.pos()), 2050 desiredAssertionStatusSym))); 2051 JCVariableDecl assertDisabledDef = make.VarDef(assertDisabledSym, 2052 notStatus); 2053 containerDef.defs = containerDef.defs.prepend(assertDisabledDef); 2054 2055 if (currentClass.isInterface()) { 2056 //need to load the assertions enabled/disabled state while 2057 //initializing the interface: 2058 JCClassDecl currentClassDef = classDef(currentClass); 2059 make_at(currentClassDef.pos()); 2060 JCStatement dummy = make.If(make.QualIdent(assertDisabledSym), make.Skip(), null); 2061 JCBlock clinit = make.Block(STATIC, List.of(dummy)); 2062 currentClassDef.defs = currentClassDef.defs.prepend(clinit); 2063 } 2064 } 2065 make_at(pos); 2066 return makeUnary(NOT, make.Ident(assertDisabledSym)); 2067 } 2068 2069 2070 /************************************************************************** 2071 * Building blocks for let expressions 2072 *************************************************************************/ 2073 2074 interface TreeBuilder { 2075 JCExpression build(JCExpression arg); 2076 } 2077 2078 /** Construct an expression using the builder, with the given rval 2079 * expression as an argument to the builder. However, the rval 2080 * expression must be computed only once, even if used multiple 2081 * times in the result of the builder. We do that by 2082 * constructing a "let" expression that saves the rvalue into a 2083 * temporary variable and then uses the temporary variable in 2084 * place of the expression built by the builder. The complete 2085 * resulting expression is of the form 2086 * <pre> 2087 * (let <b>TYPE</b> <b>TEMP</b> = <b>RVAL</b>; 2088 * in (<b>BUILDER</b>(<b>TEMP</b>))) 2089 * </pre> 2090 * where <code><b>TEMP</b></code> is a newly declared variable 2091 * in the let expression. 2092 */ 2093 JCExpression abstractRval(JCExpression rval, Type type, TreeBuilder builder) { 2094 rval = TreeInfo.skipParens(rval); 2095 switch (rval.getTag()) { 2096 case LITERAL: 2097 return builder.build(rval); 2098 case IDENT: 2099 JCIdent id = (JCIdent) rval; 2100 if ((id.sym.flags() & FINAL) != 0 && id.sym.owner.kind == MTH) 2101 return builder.build(rval); 2102 } 2103 Name name = TreeInfo.name(rval); 2104 if (name == names._super || name == names._this) 2105 return builder.build(rval); 2106 VarSymbol var = 2107 new VarSymbol(FINAL|SYNTHETIC, 2108 names.fromString( 2109 target.syntheticNameChar() 2110 + "" + rval.hashCode()), 2111 type, 2112 currentMethodSym); 2113 rval = convert(rval,type); 2114 JCVariableDecl def = make.VarDef(var, rval); // XXX cast 2115 JCExpression built = builder.build(make.Ident(var)); 2116 JCExpression res = make.LetExpr(def, built); 2117 res.type = built.type; 2118 return res; 2119 } 2120 2121 // same as above, with the type of the temporary variable computed 2122 JCExpression abstractRval(JCExpression rval, TreeBuilder builder) { 2123 return abstractRval(rval, rval.type, builder); 2124 } 2125 2126 // same as above, but for an expression that may be used as either 2127 // an rvalue or an lvalue. This requires special handling for 2128 // Select expressions, where we place the left-hand-side of the 2129 // select in a temporary, and for Indexed expressions, where we 2130 // place both the indexed expression and the index value in temps. 2131 JCExpression abstractLval(JCExpression lval, final TreeBuilder builder) { 2132 lval = TreeInfo.skipParens(lval); 2133 switch (lval.getTag()) { 2134 case IDENT: 2135 return builder.build(lval); 2136 case SELECT: { 2137 final JCFieldAccess s = (JCFieldAccess)lval; 2138 Symbol lid = TreeInfo.symbol(s.selected); 2139 if (lid != null && lid.kind == TYP) return builder.build(lval); 2140 return abstractRval(s.selected, selected -> builder.build(make.Select(selected, s.sym))); 2141 } 2142 case INDEXED: { 2143 final JCArrayAccess i = (JCArrayAccess)lval; 2144 return abstractRval(i.indexed, indexed -> abstractRval(i.index, syms.intType, index -> { 2145 JCExpression newLval = make.Indexed(indexed, index); 2146 newLval.setType(i.type); 2147 return builder.build(newLval); 2148 })); 2149 } 2150 case TYPECAST: { 2151 return abstractLval(((JCTypeCast)lval).expr, builder); 2152 } 2153 } 2154 throw new AssertionError(lval); 2155 } 2156 2157 // evaluate and discard the first expression, then evaluate the second. 2158 JCExpression makeComma(final JCExpression expr1, final JCExpression expr2) { 2159 JCExpression res = make.LetExpr(List.of(make.Exec(expr1)), expr2); 2160 res.type = expr2.type; 2161 return res; 2162 } 2163 2164 /************************************************************************** 2165 * Translation methods 2166 *************************************************************************/ 2167 2168 /** Visitor argument: enclosing operator node. 2169 */ 2170 private JCExpression enclOp; 2171 2172 /** Visitor method: Translate a single node. 2173 * Attach the source position from the old tree to its replacement tree. 2174 */ 2175 @Override 2176 public <T extends JCTree> T translate(T tree) { 2177 if (tree == null) { 2178 return null; 2179 } else { 2180 make_at(tree.pos()); 2181 T result = super.translate(tree); 2182 if (endPosTable != null && result != tree) { 2183 endPosTable.replaceTree(tree, result); 2184 } 2185 return result; 2186 } 2187 } 2188 2189 /** Visitor method: Translate a single node, boxing or unboxing if needed. 2190 */ 2191 public <T extends JCExpression> T translate(T tree, Type type) { 2192 return (tree == null) ? null : boxIfNeeded(translate(tree), type); 2193 } 2194 2195 /** Visitor method: Translate tree. 2196 */ 2197 public <T extends JCTree> T translate(T tree, JCExpression enclOp) { 2198 JCExpression prevEnclOp = this.enclOp; 2199 this.enclOp = enclOp; 2200 T res = translate(tree); 2201 this.enclOp = prevEnclOp; 2202 return res; 2203 } 2204 2205 /** Visitor method: Translate list of trees. 2206 */ 2207 public <T extends JCExpression> List<T> translate(List<T> trees, Type type) { 2208 if (trees == null) return null; 2209 for (List<T> l = trees; l.nonEmpty(); l = l.tail) 2210 l.head = translate(l.head, type); 2211 return trees; 2212 } 2213 2214 public void visitPackageDef(JCPackageDecl tree) { 2215 if (!needPackageInfoClass(tree)) 2216 return; 2217 2218 long flags = Flags.ABSTRACT | Flags.INTERFACE; 2219 // package-info is marked SYNTHETIC in JDK 1.6 and later releases 2220 flags = flags | Flags.SYNTHETIC; 2221 ClassSymbol c = tree.packge.package_info; 2222 c.setAttributes(tree.packge); 2223 c.flags_field |= flags; 2224 ClassType ctype = (ClassType) c.type; 2225 ctype.supertype_field = syms.objectType; 2226 ctype.interfaces_field = List.nil(); 2227 createInfoClass(tree.annotations, c); 2228 } 2229 // where 2230 private boolean needPackageInfoClass(JCPackageDecl pd) { 2231 switch (pkginfoOpt) { 2232 case ALWAYS: 2233 return true; 2234 case LEGACY: 2235 return pd.getAnnotations().nonEmpty(); 2236 case NONEMPTY: 2237 for (Attribute.Compound a : 2238 pd.packge.getDeclarationAttributes()) { 2239 Attribute.RetentionPolicy p = types.getRetention(a); 2240 if (p != Attribute.RetentionPolicy.SOURCE) 2241 return true; 2242 } 2243 return false; 2244 } 2245 throw new AssertionError(); 2246 } 2247 2248 public void visitModuleDef(JCModuleDecl tree) { 2249 ModuleSymbol msym = tree.sym; 2250 ClassSymbol c = msym.module_info; 2251 c.setAttributes(msym); 2252 c.flags_field |= Flags.MODULE; 2253 createInfoClass(List.nil(), tree.sym.module_info); 2254 } 2255 2256 private void createInfoClass(List<JCAnnotation> annots, ClassSymbol c) { 2257 long flags = Flags.ABSTRACT | Flags.INTERFACE; 2258 JCClassDecl infoClass = 2259 make.ClassDef(make.Modifiers(flags, annots), 2260 c.name, List.nil(), 2261 null, List.nil(), List.nil()); 2262 infoClass.sym = c; 2263 translated.append(infoClass); 2264 } 2265 2266 public void visitClassDef(JCClassDecl tree) { 2267 Env<AttrContext> prevEnv = attrEnv; 2268 ClassSymbol currentClassPrev = currentClass; 2269 MethodSymbol currentMethodSymPrev = currentMethodSym; 2270 2271 currentClass = tree.sym; 2272 currentMethodSym = null; 2273 attrEnv = typeEnvs.remove(currentClass); 2274 if (attrEnv == null) 2275 attrEnv = prevEnv; 2276 2277 classdefs.put(currentClass, tree); 2278 2279 Map<Symbol, Symbol> prevProxies = proxies; 2280 proxies = new HashMap<>(proxies); 2281 List<VarSymbol> prevOuterThisStack = outerThisStack; 2282 2283 // If this is an enum definition 2284 if ((tree.mods.flags & ENUM) != 0 && 2285 (types.supertype(currentClass.type).tsym.flags() & ENUM) == 0) 2286 visitEnumDef(tree); 2287 2288 if ((tree.mods.flags & RECORD) != 0) { 2289 visitRecordDef(tree); 2290 } 2291 2292 // If this is a nested class, define a this$n field for 2293 // it and add to proxies. 2294 JCVariableDecl otdef = null; 2295 if (currentClass.hasOuterInstance()) 2296 otdef = outerThisDef(tree.pos, currentClass); 2297 2298 // If this is a local class, define proxies for all its free variables. 2299 List<JCVariableDecl> fvdefs = freevarDefs( 2300 tree.pos, freevars(currentClass), currentClass); 2301 2302 // Recursively translate superclass, interfaces. 2303 tree.extending = translate(tree.extending); 2304 tree.implementing = translate(tree.implementing); 2305 2306 if (currentClass.isDirectlyOrIndirectlyLocal()) { 2307 ClassSymbol encl = currentClass.owner.enclClass(); 2308 if (encl.trans_local == null) { 2309 encl.trans_local = List.nil(); 2310 } 2311 encl.trans_local = encl.trans_local.prepend(currentClass); 2312 } 2313 2314 // Recursively translate members, taking into account that new members 2315 // might be created during the translation and prepended to the member 2316 // list `tree.defs'. 2317 List<JCTree> seen = List.nil(); 2318 while (tree.defs != seen) { 2319 List<JCTree> unseen = tree.defs; 2320 for (List<JCTree> l = unseen; l.nonEmpty() && l != seen; l = l.tail) { 2321 JCTree outermostMemberDefPrev = outermostMemberDef; 2322 if (outermostMemberDefPrev == null) outermostMemberDef = l.head; 2323 l.head = translate(l.head); 2324 outermostMemberDef = outermostMemberDefPrev; 2325 } 2326 seen = unseen; 2327 } 2328 2329 // Convert a protected modifier to public, mask static modifier. 2330 if ((tree.mods.flags & PROTECTED) != 0) tree.mods.flags |= PUBLIC; 2331 tree.mods.flags &= ClassFlags; 2332 2333 // Convert name to flat representation, replacing '.' by '$'. 2334 tree.name = Convert.shortName(currentClass.flatName()); 2335 2336 // Add free variables proxy definitions to class. 2337 2338 for (List<JCVariableDecl> l = fvdefs; l.nonEmpty(); l = l.tail) { 2339 tree.defs = tree.defs.prepend(l.head); 2340 enterSynthetic(tree.pos(), l.head.sym, currentClass.members()); 2341 } 2342 // If this$n was accessed, add the field definition and 2343 // update initial constructors to initialize it 2344 if (currentClass.hasOuterInstance() && shouldEmitOuterThis(currentClass)) { 2345 tree.defs = tree.defs.prepend(otdef); 2346 enterSynthetic(tree.pos(), otdef.sym, currentClass.members()); 2347 2348 for (JCTree def : tree.defs) { 2349 if (TreeInfo.isInitialConstructor(def)) { 2350 JCMethodDecl mdef = (JCMethodDecl) def; 2351 mdef.body.stats = mdef.body.stats.prepend( 2352 initOuterThis(mdef.body.pos, mdef.params.head.sym)); 2353 } 2354 } 2355 } 2356 2357 proxies = prevProxies; 2358 outerThisStack = prevOuterThisStack; 2359 2360 // Append translated tree to `translated' queue. 2361 translated.append(tree); 2362 2363 attrEnv = prevEnv; 2364 currentClass = currentClassPrev; 2365 currentMethodSym = currentMethodSymPrev; 2366 2367 // Return empty block {} as a placeholder for an inner class. 2368 result = make_at(tree.pos()).Block(SYNTHETIC, List.nil()); 2369 } 2370 2371 private boolean shouldEmitOuterThis(ClassSymbol sym) { 2372 if (!optimizeOuterThis) { 2373 // Optimization is disabled 2374 return true; 2375 } 2376 if ((outerThisStack.head.flags_field & NOOUTERTHIS) == 0) { 2377 // Enclosing instance field is used 2378 return true; 2379 } 2380 if (rs.isSerializable(sym.type)) { 2381 // Class is serializable 2382 return true; 2383 } 2384 return false; 2385 } 2386 2387 List<JCTree> generateMandatedAccessors(JCClassDecl tree) { 2388 List<JCVariableDecl> fields = TreeInfo.recordFields(tree); 2389 return tree.sym.getRecordComponents().stream() 2390 .filter(rc -> (rc.accessor.flags() & Flags.GENERATED_MEMBER) != 0) 2391 .map(rc -> { 2392 // we need to return the field not the record component 2393 JCVariableDecl field = fields.stream().filter(f -> f.name == rc.name).findAny().get(); 2394 make_at(tree.pos()); 2395 return make.MethodDef(rc.accessor, make.Block(0, 2396 List.of(make.Return(make.Ident(field))))); 2397 }).collect(List.collector()); 2398 } 2399 2400 /** Translate an enum class. */ 2401 private void visitEnumDef(JCClassDecl tree) { 2402 make_at(tree.pos()); 2403 2404 // add the supertype, if needed 2405 if (tree.extending == null) 2406 tree.extending = make.Type(types.supertype(tree.type)); 2407 2408 // classOfType adds a cache field to tree.defs 2409 JCExpression e_class = classOfType(tree.sym.type, tree.pos()). 2410 setType(types.erasure(syms.classType)); 2411 2412 // process each enumeration constant, adding implicit constructor parameters 2413 int nextOrdinal = 0; 2414 ListBuffer<JCExpression> values = new ListBuffer<>(); 2415 ListBuffer<JCTree> enumDefs = new ListBuffer<>(); 2416 ListBuffer<JCTree> otherDefs = new ListBuffer<>(); 2417 for (List<JCTree> defs = tree.defs; 2418 defs.nonEmpty(); 2419 defs=defs.tail) { 2420 if (defs.head.hasTag(VARDEF) && (((JCVariableDecl) defs.head).mods.flags & ENUM) != 0) { 2421 JCVariableDecl var = (JCVariableDecl)defs.head; 2422 visitEnumConstantDef(var, nextOrdinal++); 2423 values.append(make.QualIdent(var.sym)); 2424 enumDefs.append(var); 2425 } else { 2426 otherDefs.append(defs.head); 2427 } 2428 } 2429 2430 // synthetic private static T[] $values() { return new T[] { a, b, c }; } 2431 // synthetic private static final T[] $VALUES = $values(); 2432 Name valuesName = syntheticName(tree, "VALUES"); 2433 Type arrayType = new ArrayType(types.erasure(tree.type), syms.arrayClass); 2434 VarSymbol valuesVar = new VarSymbol(PRIVATE|FINAL|STATIC|SYNTHETIC, 2435 valuesName, 2436 arrayType, 2437 tree.type.tsym); 2438 JCNewArray newArray = make.NewArray(make.Type(types.erasure(tree.type)), 2439 List.nil(), 2440 values.toList()); 2441 newArray.type = arrayType; 2442 2443 MethodSymbol valuesMethod = new MethodSymbol(PRIVATE|STATIC|SYNTHETIC, 2444 syntheticName(tree, "values"), 2445 new MethodType(List.nil(), arrayType, List.nil(), tree.type.tsym), 2446 tree.type.tsym); 2447 enumDefs.append(make.MethodDef(valuesMethod, make.Block(0, List.of(make.Return(newArray))))); 2448 tree.sym.members().enter(valuesMethod); 2449 2450 enumDefs.append(make.VarDef(valuesVar, make.App(make.QualIdent(valuesMethod)))); 2451 tree.sym.members().enter(valuesVar); 2452 2453 MethodSymbol valuesSym = lookupMethod(tree.pos(), names.values, 2454 tree.type, List.nil()); 2455 List<JCStatement> valuesBody; 2456 if (useClone()) { 2457 // return (T[]) $VALUES.clone(); 2458 JCTypeCast valuesResult = 2459 make.TypeCast(valuesSym.type.getReturnType(), 2460 make.App(make.Select(make.Ident(valuesVar), 2461 syms.arrayCloneMethod))); 2462 valuesBody = List.of(make.Return(valuesResult)); 2463 } else { 2464 // template: T[] $result = new T[$values.length]; 2465 Name resultName = syntheticName(tree, "result"); 2466 VarSymbol resultVar = new VarSymbol(FINAL|SYNTHETIC, 2467 resultName, 2468 arrayType, 2469 valuesSym); 2470 JCNewArray resultArray = make.NewArray(make.Type(types.erasure(tree.type)), 2471 List.of(make.Select(make.Ident(valuesVar), syms.lengthVar)), 2472 null); 2473 resultArray.type = arrayType; 2474 JCVariableDecl decl = make.VarDef(resultVar, resultArray); 2475 2476 // template: System.arraycopy($VALUES, 0, $result, 0, $VALUES.length); 2477 if (systemArraycopyMethod == null) { 2478 systemArraycopyMethod = 2479 new MethodSymbol(PUBLIC | STATIC, 2480 names.fromString("arraycopy"), 2481 new MethodType(List.of(syms.objectType, 2482 syms.intType, 2483 syms.objectType, 2484 syms.intType, 2485 syms.intType), 2486 syms.voidType, 2487 List.nil(), 2488 syms.methodClass), 2489 syms.systemType.tsym); 2490 } 2491 JCStatement copy = 2492 make.Exec(make.App(make.Select(make.Ident(syms.systemType.tsym), 2493 systemArraycopyMethod), 2494 List.of(make.Ident(valuesVar), make.Literal(0), 2495 make.Ident(resultVar), make.Literal(0), 2496 make.Select(make.Ident(valuesVar), syms.lengthVar)))); 2497 2498 // template: return $result; 2499 JCStatement ret = make.Return(make.Ident(resultVar)); 2500 valuesBody = List.of(decl, copy, ret); 2501 } 2502 2503 JCMethodDecl valuesDef = 2504 make.MethodDef(valuesSym, make.Block(0, valuesBody)); 2505 2506 enumDefs.append(valuesDef); 2507 2508 if (debugLower) 2509 System.err.println(tree.sym + ".valuesDef = " + valuesDef); 2510 2511 /** The template for the following code is: 2512 * 2513 * public static E valueOf(String name) { 2514 * return (E)Enum.valueOf(E.class, name); 2515 * } 2516 * 2517 * where E is tree.sym 2518 */ 2519 MethodSymbol valueOfSym = lookupMethod(tree.pos(), 2520 names.valueOf, 2521 tree.sym.type, 2522 List.of(syms.stringType)); 2523 Assert.check((valueOfSym.flags() & STATIC) != 0); 2524 VarSymbol nameArgSym = valueOfSym.params.head; 2525 JCIdent nameVal = make.Ident(nameArgSym); 2526 JCStatement enum_ValueOf = 2527 make.Return(make.TypeCast(tree.sym.type, 2528 makeCall(make.Ident(syms.enumSym), 2529 names.valueOf, 2530 List.of(e_class, nameVal)))); 2531 JCMethodDecl valueOf = make.MethodDef(valueOfSym, 2532 make.Block(0, List.of(enum_ValueOf))); 2533 nameVal.sym = valueOf.params.head.sym; 2534 if (debugLower) 2535 System.err.println(tree.sym + ".valueOf = " + valueOf); 2536 enumDefs.append(valueOf); 2537 2538 enumDefs.appendList(otherDefs.toList()); 2539 tree.defs = enumDefs.toList(); 2540 } 2541 // where 2542 private MethodSymbol systemArraycopyMethod; 2543 private boolean useClone() { 2544 try { 2545 return syms.objectType.tsym.members().findFirst(names.clone) != null; 2546 } 2547 catch (CompletionFailure e) { 2548 return false; 2549 } 2550 } 2551 2552 private Name syntheticName(JCClassDecl tree, String baseName) { 2553 Name valuesName = names.fromString(target.syntheticNameChar() + baseName); 2554 while (tree.sym.members().findFirst(valuesName) != null) // avoid name clash 2555 valuesName = names.fromString(valuesName + "" + target.syntheticNameChar()); 2556 return valuesName; 2557 } 2558 2559 /** Translate an enumeration constant and its initializer. */ 2560 private void visitEnumConstantDef(JCVariableDecl var, int ordinal) { 2561 JCNewClass varDef = (JCNewClass)var.init; 2562 varDef.args = varDef.args. 2563 prepend(makeLit(syms.intType, ordinal)). 2564 prepend(makeLit(syms.stringType, var.name.toString())); 2565 } 2566 2567 private List<VarSymbol> recordVars(Type t) { 2568 List<VarSymbol> vars = List.nil(); 2569 while (!t.hasTag(NONE)) { 2570 if (t.hasTag(CLASS)) { 2571 for (Symbol s : t.tsym.members().getSymbols(s -> s.kind == VAR && (s.flags() & RECORD) != 0)) { 2572 vars = vars.prepend((VarSymbol)s); 2573 } 2574 } 2575 t = types.supertype(t); 2576 } 2577 return vars; 2578 } 2579 2580 /** Translate a record. */ 2581 private void visitRecordDef(JCClassDecl tree) { 2582 make_at(tree.pos()); 2583 List<VarSymbol> vars = recordVars(tree.type); 2584 MethodHandleSymbol[] getterMethHandles = new MethodHandleSymbol[vars.size()]; 2585 int index = 0; 2586 for (VarSymbol var : vars) { 2587 if (var.owner != tree.sym) { 2588 var = new VarSymbol(var.flags_field, var.name, var.type, tree.sym); 2589 } 2590 getterMethHandles[index] = var.asMethodHandle(true); 2591 index++; 2592 } 2593 2594 tree.defs = tree.defs.appendList(generateMandatedAccessors(tree)); 2595 tree.defs = tree.defs.appendList(List.of( 2596 generateRecordMethod(tree, names.toString, vars, getterMethHandles), 2597 generateRecordMethod(tree, names.hashCode, vars, getterMethHandles), 2598 generateRecordMethod(tree, names.equals, vars, getterMethHandles) 2599 )); 2600 } 2601 2602 JCTree generateRecordMethod(JCClassDecl tree, Name name, List<VarSymbol> vars, MethodHandleSymbol[] getterMethHandles) { 2603 make_at(tree.pos()); 2604 boolean isEquals = name == names.equals; 2605 MethodSymbol msym = lookupMethod(tree.pos(), 2606 name, 2607 tree.sym.type, 2608 isEquals ? List.of(syms.objectType) : List.nil()); 2609 // compiler generated methods have the record flag set, user defined ones dont 2610 if ((msym.flags() & RECORD) != 0) { 2611 /* class java.lang.runtime.ObjectMethods provides a common bootstrap that provides a customized implementation 2612 * for methods: toString, hashCode and equals. Here we just need to generate and indy call to: 2613 * java.lang.runtime.ObjectMethods::bootstrap and provide: the record class, the record component names and 2614 * the accessors. 2615 */ 2616 Name bootstrapName = names.bootstrap; 2617 LoadableConstant[] staticArgsValues = new LoadableConstant[2 + getterMethHandles.length]; 2618 staticArgsValues[0] = (ClassType)tree.sym.type; 2619 String concatNames = vars.stream() 2620 .map(v -> v.name) 2621 .collect(Collectors.joining(";", "", "")); 2622 staticArgsValues[1] = LoadableConstant.String(concatNames); 2623 int index = 2; 2624 for (MethodHandleSymbol mho : getterMethHandles) { 2625 staticArgsValues[index] = mho; 2626 index++; 2627 } 2628 2629 List<Type> staticArgTypes = List.of(syms.classType, 2630 syms.stringType, 2631 new ArrayType(syms.methodHandleType, syms.arrayClass)); 2632 2633 JCFieldAccess qualifier = makeIndyQualifier(syms.objectMethodsType, tree, msym, 2634 List.of(syms.methodHandleLookupType, 2635 syms.stringType, 2636 syms.typeDescriptorType).appendList(staticArgTypes), 2637 staticArgsValues, bootstrapName, name, false); 2638 2639 VarSymbol _this = new VarSymbol(SYNTHETIC, names._this, tree.sym.type, tree.sym); 2640 2641 JCMethodInvocation proxyCall; 2642 if (!isEquals) { 2643 proxyCall = make.Apply(List.nil(), qualifier, List.of(make.Ident(_this))); 2644 } else { 2645 VarSymbol o = msym.params.head; 2646 o.adr = 0; 2647 proxyCall = make.Apply(List.nil(), qualifier, List.of(make.Ident(_this), make.Ident(o))); 2648 } 2649 proxyCall.type = qualifier.type; 2650 return make.MethodDef(msym, make.Block(0, List.of(make.Return(proxyCall)))); 2651 } else { 2652 return make.Block(SYNTHETIC, List.nil()); 2653 } 2654 } 2655 2656 private String argsTypeSig(List<Type> typeList) { 2657 LowerSignatureGenerator sg = new LowerSignatureGenerator(); 2658 sg.assembleSig(typeList); 2659 return sg.toString(); 2660 } 2661 2662 /** 2663 * Signature Generation 2664 */ 2665 private class LowerSignatureGenerator extends Types.SignatureGenerator { 2666 2667 /** 2668 * An output buffer for type signatures. 2669 */ 2670 StringBuilder sb = new StringBuilder(); 2671 2672 LowerSignatureGenerator() { 2673 super(types); 2674 } 2675 2676 @Override 2677 protected void append(char ch) { 2678 sb.append(ch); 2679 } 2680 2681 @Override 2682 protected void append(byte[] ba) { 2683 sb.append(new String(ba)); 2684 } 2685 2686 @Override 2687 protected void append(Name name) { 2688 sb.append(name.toString()); 2689 } 2690 2691 @Override 2692 public String toString() { 2693 return sb.toString(); 2694 } 2695 } 2696 2697 /** 2698 * Creates an indy qualifier, helpful to be part of an indy invocation 2699 * @param site the site 2700 * @param tree a class declaration tree 2701 * @param msym the method symbol 2702 * @param staticArgTypes the static argument types 2703 * @param staticArgValues the static argument values 2704 * @param bootstrapName the bootstrap name to look for 2705 * @param argName normally bootstraps receives a method name as second argument, if you want that name 2706 * to be different to that of the bootstrap name pass a different name here 2707 * @param isStatic is it static or not 2708 * @return a field access tree 2709 */ 2710 JCFieldAccess makeIndyQualifier( 2711 Type site, 2712 JCClassDecl tree, 2713 MethodSymbol msym, 2714 List<Type> staticArgTypes, 2715 LoadableConstant[] staticArgValues, 2716 Name bootstrapName, 2717 Name argName, 2718 boolean isStatic) { 2719 MethodSymbol bsm = rs.resolveInternalMethod(tree.pos(), attrEnv, site, 2720 bootstrapName, staticArgTypes, List.nil()); 2721 2722 MethodType indyType = msym.type.asMethodType(); 2723 indyType = new MethodType( 2724 isStatic ? List.nil() : indyType.argtypes.prepend(tree.sym.type), 2725 indyType.restype, 2726 indyType.thrown, 2727 syms.methodClass 2728 ); 2729 DynamicMethodSymbol dynSym = new DynamicMethodSymbol(argName, 2730 syms.noSymbol, 2731 bsm.asHandle(), 2732 indyType, 2733 staticArgValues); 2734 JCFieldAccess qualifier = make.Select(make.QualIdent(site.tsym), argName); 2735 qualifier.sym = dynSym; 2736 qualifier.type = msym.type.asMethodType().restype; 2737 return qualifier; 2738 } 2739 2740 public void visitMethodDef(JCMethodDecl tree) { 2741 if (tree.name == names.init && (currentClass.flags_field&ENUM) != 0) { 2742 // Add "String $enum$name, int $enum$ordinal" to the beginning of the 2743 // argument list for each constructor of an enum. 2744 JCVariableDecl nameParam = make_at(tree.pos()). 2745 Param(names.fromString(target.syntheticNameChar() + 2746 "enum" + target.syntheticNameChar() + "name"), 2747 syms.stringType, tree.sym); 2748 nameParam.mods.flags |= SYNTHETIC; nameParam.sym.flags_field |= SYNTHETIC; 2749 JCVariableDecl ordParam = make. 2750 Param(names.fromString(target.syntheticNameChar() + 2751 "enum" + target.syntheticNameChar() + 2752 "ordinal"), 2753 syms.intType, tree.sym); 2754 ordParam.mods.flags |= SYNTHETIC; ordParam.sym.flags_field |= SYNTHETIC; 2755 2756 MethodSymbol m = tree.sym; 2757 tree.params = tree.params.prepend(ordParam).prepend(nameParam); 2758 2759 m.extraParams = m.extraParams.prepend(ordParam.sym); 2760 m.extraParams = m.extraParams.prepend(nameParam.sym); 2761 Type olderasure = m.erasure(types); 2762 m.erasure_field = new MethodType( 2763 olderasure.getParameterTypes().prepend(syms.intType).prepend(syms.stringType), 2764 olderasure.getReturnType(), 2765 olderasure.getThrownTypes(), 2766 syms.methodClass); 2767 } 2768 2769 JCMethodDecl prevMethodDef = currentMethodDef; 2770 MethodSymbol prevMethodSym = currentMethodSym; 2771 try { 2772 currentMethodDef = tree; 2773 currentMethodSym = tree.sym; 2774 visitMethodDefInternal(tree); 2775 } finally { 2776 currentMethodDef = prevMethodDef; 2777 currentMethodSym = prevMethodSym; 2778 } 2779 } 2780 2781 private void visitMethodDefInternal(JCMethodDecl tree) { 2782 if (tree.name == names.init && 2783 !currentClass.isStatic() && 2784 (currentClass.isInner() || currentClass.isDirectlyOrIndirectlyLocal())) { 2785 // We are seeing a constructor of an inner class. 2786 MethodSymbol m = tree.sym; 2787 2788 // Push a new proxy scope for constructor parameters. 2789 // and create definitions for any this$n and proxy parameters. 2790 Map<Symbol, Symbol> prevProxies = proxies; 2791 proxies = new HashMap<>(proxies); 2792 List<VarSymbol> prevOuterThisStack = outerThisStack; 2793 List<VarSymbol> fvs = freevars(currentClass); 2794 JCVariableDecl otdef = null; 2795 if (currentClass.hasOuterInstance()) 2796 otdef = outerThisDef(tree.pos, m); 2797 List<JCVariableDecl> fvdefs = freevarDefs(tree.pos, fvs, m, PARAMETER); 2798 2799 // Recursively translate result type, parameters and thrown list. 2800 tree.restype = translate(tree.restype); 2801 tree.params = translateVarDefs(tree.params); 2802 tree.thrown = translate(tree.thrown); 2803 2804 // when compiling stubs, don't process body 2805 if (tree.body == null) { 2806 result = tree; 2807 return; 2808 } 2809 2810 // Add this$n (if needed) in front of and free variables behind 2811 // constructor parameter list. 2812 tree.params = tree.params.appendList(fvdefs); 2813 if (currentClass.hasOuterInstance()) { 2814 tree.params = tree.params.prepend(otdef); 2815 } 2816 2817 // If this is an initial constructor, i.e., it does not start with 2818 // this(...), insert initializers for this$n and proxies 2819 // before (pre-1.4, after) the call to superclass constructor. 2820 JCStatement selfCall = translate(tree.body.stats.head); 2821 2822 List<JCStatement> added = List.nil(); 2823 if (fvs.nonEmpty()) { 2824 List<Type> addedargtypes = List.nil(); 2825 for (List<VarSymbol> l = fvs; l.nonEmpty(); l = l.tail) { 2826 m.capturedLocals = 2827 m.capturedLocals.prepend((VarSymbol) 2828 (proxies.get(l.head))); 2829 if (TreeInfo.isInitialConstructor(tree)) { 2830 added = added.prepend( 2831 initField(tree.body.pos, proxies.get(l.head), prevProxies.get(l.head))); 2832 } 2833 addedargtypes = addedargtypes.prepend(l.head.erasure(types)); 2834 } 2835 Type olderasure = m.erasure(types); 2836 m.erasure_field = new MethodType( 2837 olderasure.getParameterTypes().appendList(addedargtypes), 2838 olderasure.getReturnType(), 2839 olderasure.getThrownTypes(), 2840 syms.methodClass); 2841 } 2842 2843 // pop local variables from proxy stack 2844 proxies = prevProxies; 2845 2846 // recursively translate following local statements and 2847 // combine with this- or super-call 2848 List<JCStatement> stats = translate(tree.body.stats.tail); 2849 tree.body.stats = stats.prepend(selfCall).prependList(added); 2850 outerThisStack = prevOuterThisStack; 2851 } else { 2852 Map<Symbol, Symbol> prevLambdaTranslationMap = 2853 lambdaTranslationMap; 2854 try { 2855 lambdaTranslationMap = (tree.sym.flags() & SYNTHETIC) != 0 && 2856 tree.sym.name.startsWith(names.lambda) ? 2857 makeTranslationMap(tree) : null; 2858 super.visitMethodDef(tree); 2859 } finally { 2860 lambdaTranslationMap = prevLambdaTranslationMap; 2861 } 2862 } 2863 if (tree.name == names.init && ((tree.sym.flags_field & Flags.COMPACT_RECORD_CONSTRUCTOR) != 0 || 2864 (tree.sym.flags_field & (GENERATEDCONSTR | RECORD)) == (GENERATEDCONSTR | RECORD))) { 2865 // lets find out if there is any field waiting to be initialized 2866 ListBuffer<VarSymbol> fields = new ListBuffer<>(); 2867 for (Symbol sym : currentClass.getEnclosedElements()) { 2868 if (sym.kind == Kinds.Kind.VAR && ((sym.flags() & RECORD) != 0)) 2869 fields.append((VarSymbol) sym); 2870 } 2871 for (VarSymbol field: fields) { 2872 if ((field.flags_field & Flags.UNINITIALIZED_FIELD) != 0) { 2873 VarSymbol param = tree.params.stream().filter(p -> p.name == field.name).findFirst().get().sym; 2874 make.at(tree.pos); 2875 tree.body.stats = tree.body.stats.append( 2876 make.Exec( 2877 make.Assign( 2878 make.Select(make.This(field.owner.erasure(types)), field), 2879 make.Ident(param)).setType(field.erasure(types)))); 2880 // we don't need the flag at the field anymore 2881 field.flags_field &= ~Flags.UNINITIALIZED_FIELD; 2882 } 2883 } 2884 } 2885 result = tree; 2886 } 2887 //where 2888 private Map<Symbol, Symbol> makeTranslationMap(JCMethodDecl tree) { 2889 Map<Symbol, Symbol> translationMap = new HashMap<>(); 2890 for (JCVariableDecl vd : tree.params) { 2891 Symbol p = vd.sym; 2892 if (p != p.baseSymbol()) { 2893 translationMap.put(p.baseSymbol(), p); 2894 } 2895 } 2896 return translationMap; 2897 } 2898 2899 public void visitTypeCast(JCTypeCast tree) { 2900 tree.clazz = translate(tree.clazz); 2901 if (tree.type.isPrimitive() != tree.expr.type.isPrimitive()) 2902 tree.expr = translate(tree.expr, tree.type); 2903 else 2904 tree.expr = translate(tree.expr); 2905 result = tree; 2906 } 2907 2908 public void visitNewClass(JCNewClass tree) { 2909 ClassSymbol c = (ClassSymbol)tree.constructor.owner; 2910 2911 // Box arguments, if necessary 2912 boolean isEnum = (tree.constructor.owner.flags() & ENUM) != 0; 2913 List<Type> argTypes = tree.constructor.type.getParameterTypes(); 2914 if (isEnum) argTypes = argTypes.prepend(syms.intType).prepend(syms.stringType); 2915 tree.args = boxArgs(argTypes, tree.args, tree.varargsElement); 2916 tree.varargsElement = null; 2917 2918 // If created class is local, add free variables after 2919 // explicit constructor arguments. 2920 if (c.isDirectlyOrIndirectlyLocal() && !c.isStatic()) { 2921 tree.args = tree.args.appendList(loadFreevars(tree.pos(), freevars(c))); 2922 } 2923 2924 // If an access constructor is used, append null as a last argument. 2925 Symbol constructor = accessConstructor(tree.pos(), tree.constructor); 2926 if (constructor != tree.constructor) { 2927 tree.args = tree.args.append(makeNull()); 2928 tree.constructor = constructor; 2929 } 2930 2931 // If created class has an outer instance, and new is qualified, pass 2932 // qualifier as first argument. If new is not qualified, pass the 2933 // correct outer instance as first argument. 2934 if (c.hasOuterInstance()) { 2935 JCExpression thisArg; 2936 if (tree.encl != null) { 2937 thisArg = attr.makeNullCheck(translate(tree.encl)); 2938 thisArg.type = tree.encl.type; 2939 } else if (c.isDirectlyOrIndirectlyLocal()) { 2940 // local class 2941 thisArg = makeThis(tree.pos(), c.type.getEnclosingType().tsym); 2942 } else { 2943 // nested class 2944 thisArg = makeOwnerThis(tree.pos(), c, false); 2945 } 2946 tree.args = tree.args.prepend(thisArg); 2947 } 2948 tree.encl = null; 2949 2950 // If we have an anonymous class, create its flat version, rather 2951 // than the class or interface following new. 2952 if (tree.def != null) { 2953 Map<Symbol, Symbol> prevLambdaTranslationMap = lambdaTranslationMap; 2954 try { 2955 lambdaTranslationMap = null; 2956 translate(tree.def); 2957 } finally { 2958 lambdaTranslationMap = prevLambdaTranslationMap; 2959 } 2960 2961 tree.clazz = access(make_at(tree.clazz.pos()).Ident(tree.def.sym)); 2962 tree.def = null; 2963 } else { 2964 tree.clazz = access(c, tree.clazz, enclOp, false); 2965 } 2966 result = tree; 2967 } 2968 2969 // Simplify conditionals with known constant controlling expressions. 2970 // This allows us to avoid generating supporting declarations for 2971 // the dead code, which will not be eliminated during code generation. 2972 // Note that Flow.isFalse and Flow.isTrue only return true 2973 // for constant expressions in the sense of JLS 15.27, which 2974 // are guaranteed to have no side-effects. More aggressive 2975 // constant propagation would require that we take care to 2976 // preserve possible side-effects in the condition expression. 2977 2978 // One common case is equality expressions involving a constant and null. 2979 // Since null is not a constant expression (because null cannot be 2980 // represented in the constant pool), equality checks involving null are 2981 // not captured by Flow.isTrue/isFalse. 2982 // Equality checks involving a constant and null, e.g. 2983 // "" == null 2984 // are safe to simplify as no side-effects can occur. 2985 2986 private boolean isTrue(JCTree exp) { 2987 if (exp.type.isTrue()) 2988 return true; 2989 Boolean b = expValue(exp); 2990 return b == null ? false : b; 2991 } 2992 private boolean isFalse(JCTree exp) { 2993 if (exp.type.isFalse()) 2994 return true; 2995 Boolean b = expValue(exp); 2996 return b == null ? false : !b; 2997 } 2998 /* look for (in)equality relations involving null. 2999 * return true - if expression is always true 3000 * false - if expression is always false 3001 * null - if expression cannot be eliminated 3002 */ 3003 private Boolean expValue(JCTree exp) { 3004 while (exp.hasTag(PARENS)) 3005 exp = ((JCParens)exp).expr; 3006 3007 boolean eq; 3008 switch (exp.getTag()) { 3009 case EQ: eq = true; break; 3010 case NE: eq = false; break; 3011 default: 3012 return null; 3013 } 3014 3015 // we have a JCBinary(EQ|NE) 3016 // check if we have two literals (constants or null) 3017 JCBinary b = (JCBinary)exp; 3018 if (b.lhs.type.hasTag(BOT)) return expValueIsNull(eq, b.rhs); 3019 if (b.rhs.type.hasTag(BOT)) return expValueIsNull(eq, b.lhs); 3020 return null; 3021 } 3022 private Boolean expValueIsNull(boolean eq, JCTree t) { 3023 if (t.type.hasTag(BOT)) return Boolean.valueOf(eq); 3024 if (t.hasTag(LITERAL)) return Boolean.valueOf(!eq); 3025 return null; 3026 } 3027 3028 /** Visitor method for conditional expressions. 3029 */ 3030 @Override 3031 public void visitConditional(JCConditional tree) { 3032 JCTree cond = tree.cond = translate(tree.cond, syms.booleanType); 3033 if (isTrue(cond)) { 3034 result = convert(translate(tree.truepart, tree.type), tree.type); 3035 addPrunedInfo(cond); 3036 } else if (isFalse(cond)) { 3037 result = convert(translate(tree.falsepart, tree.type), tree.type); 3038 addPrunedInfo(cond); 3039 } else { 3040 // Condition is not a compile-time constant. 3041 tree.truepart = translate(tree.truepart, tree.type); 3042 tree.falsepart = translate(tree.falsepart, tree.type); 3043 result = tree; 3044 } 3045 } 3046 //where 3047 private JCExpression convert(JCExpression tree, Type pt) { 3048 if (tree.type == pt || tree.type.hasTag(BOT)) 3049 return tree; 3050 JCExpression result = make_at(tree.pos()).TypeCast(make.Type(pt), tree); 3051 result.type = (tree.type.constValue() != null) ? cfolder.coerce(tree.type, pt) 3052 : pt; 3053 return result; 3054 } 3055 3056 /** Visitor method for if statements. 3057 */ 3058 public void visitIf(JCIf tree) { 3059 JCTree cond = tree.cond = translate(tree.cond, syms.booleanType); 3060 if (isTrue(cond)) { 3061 result = translate(tree.thenpart); 3062 addPrunedInfo(cond); 3063 } else if (isFalse(cond)) { 3064 if (tree.elsepart != null) { 3065 result = translate(tree.elsepart); 3066 } else { 3067 result = make.Skip(); 3068 } 3069 addPrunedInfo(cond); 3070 } else { 3071 // Condition is not a compile-time constant. 3072 tree.thenpart = translate(tree.thenpart); 3073 tree.elsepart = translate(tree.elsepart); 3074 result = tree; 3075 } 3076 } 3077 3078 /** Visitor method for assert statements. Translate them away. 3079 */ 3080 public void visitAssert(JCAssert tree) { 3081 tree.cond = translate(tree.cond, syms.booleanType); 3082 if (!tree.cond.type.isTrue()) { 3083 JCExpression cond = assertFlagTest(tree.pos()); 3084 List<JCExpression> exnArgs = (tree.detail == null) ? 3085 List.nil() : List.of(translate(tree.detail)); 3086 if (!tree.cond.type.isFalse()) { 3087 cond = makeBinary 3088 (AND, 3089 cond, 3090 makeUnary(NOT, tree.cond)); 3091 } 3092 result = 3093 make.If(cond, 3094 make_at(tree). 3095 Throw(makeNewClass(syms.assertionErrorType, exnArgs)), 3096 null); 3097 } else { 3098 result = make.Skip(); 3099 } 3100 } 3101 3102 public void visitApply(JCMethodInvocation tree) { 3103 Symbol meth = TreeInfo.symbol(tree.meth); 3104 List<Type> argtypes = meth.type.getParameterTypes(); 3105 if (meth.name == names.init && meth.owner == syms.enumSym) 3106 argtypes = argtypes.tail.tail; 3107 tree.args = boxArgs(argtypes, tree.args, tree.varargsElement); 3108 tree.varargsElement = null; 3109 Name methName = TreeInfo.name(tree.meth); 3110 if (meth.name==names.init) { 3111 // We are seeing a this(...) or super(...) constructor call. 3112 // If an access constructor is used, append null as a last argument. 3113 Symbol constructor = accessConstructor(tree.pos(), meth); 3114 if (constructor != meth) { 3115 tree.args = tree.args.append(makeNull()); 3116 TreeInfo.setSymbol(tree.meth, constructor); 3117 } 3118 3119 // If we are calling a constructor of a local class, add 3120 // free variables after explicit constructor arguments. 3121 ClassSymbol c = (ClassSymbol)constructor.owner; 3122 if (c.isDirectlyOrIndirectlyLocal() && !c.isStatic()) { 3123 tree.args = tree.args.appendList(loadFreevars(tree.pos(), freevars(c))); 3124 } 3125 3126 // If we are calling a constructor of an enum class, pass 3127 // along the name and ordinal arguments 3128 if ((c.flags_field&ENUM) != 0 || c.getQualifiedName() == names.java_lang_Enum) { 3129 List<JCVariableDecl> params = currentMethodDef.params; 3130 if (currentMethodSym.owner.hasOuterInstance()) 3131 params = params.tail; // drop this$n 3132 tree.args = tree.args 3133 .prepend(make_at(tree.pos()).Ident(params.tail.head.sym)) // ordinal 3134 .prepend(make.Ident(params.head.sym)); // name 3135 } 3136 3137 // If we are calling a constructor of a class with an outer 3138 // instance, and the call 3139 // is qualified, pass qualifier as first argument in front of 3140 // the explicit constructor arguments. If the call 3141 // is not qualified, pass the correct outer instance as 3142 // first argument. If we are a static class, there is no 3143 // such outer instance, so generate an error. 3144 if (c.hasOuterInstance()) { 3145 JCExpression thisArg; 3146 if (tree.meth.hasTag(SELECT)) { 3147 thisArg = attr. 3148 makeNullCheck(translate(((JCFieldAccess) tree.meth).selected)); 3149 tree.meth = make.Ident(constructor); 3150 ((JCIdent) tree.meth).name = methName; 3151 } else if (c.isDirectlyOrIndirectlyLocal() || methName == names._this){ 3152 // local class or this() call 3153 thisArg = makeThis(tree.meth.pos(), c.type.getEnclosingType().tsym); 3154 } else if (currentClass.isStatic()) { 3155 // super() call from static nested class - invalid 3156 log.error(tree.pos(), 3157 Errors.NoEnclInstanceOfTypeInScope(c.type.getEnclosingType().tsym)); 3158 thisArg = make.Literal(BOT, null).setType(syms.botType); 3159 } else { 3160 // super() call of nested class - never pick 'this' 3161 thisArg = makeOwnerThisN(tree.meth.pos(), c, false); 3162 } 3163 tree.args = tree.args.prepend(thisArg); 3164 } 3165 } else { 3166 // We are seeing a normal method invocation; translate this as usual. 3167 tree.meth = translate(tree.meth); 3168 3169 // If the translated method itself is an Apply tree, we are 3170 // seeing an access method invocation. In this case, append 3171 // the method arguments to the arguments of the access method. 3172 if (tree.meth.hasTag(APPLY)) { 3173 JCMethodInvocation app = (JCMethodInvocation)tree.meth; 3174 app.args = tree.args.prependList(app.args); 3175 result = app; 3176 return; 3177 } 3178 } 3179 result = tree; 3180 } 3181 3182 List<JCExpression> boxArgs(List<Type> parameters, List<JCExpression> _args, Type varargsElement) { 3183 List<JCExpression> args = _args; 3184 if (parameters.isEmpty()) return args; 3185 boolean anyChanges = false; 3186 ListBuffer<JCExpression> result = new ListBuffer<>(); 3187 while (parameters.tail.nonEmpty()) { 3188 JCExpression arg = translate(args.head, parameters.head); 3189 anyChanges |= (arg != args.head); 3190 result.append(arg); 3191 args = args.tail; 3192 parameters = parameters.tail; 3193 } 3194 Type parameter = parameters.head; 3195 if (varargsElement != null) { 3196 anyChanges = true; 3197 ListBuffer<JCExpression> elems = new ListBuffer<>(); 3198 while (args.nonEmpty()) { 3199 JCExpression arg = translate(args.head, varargsElement); 3200 elems.append(arg); 3201 args = args.tail; 3202 } 3203 JCNewArray boxedArgs = make.NewArray(make.Type(varargsElement), 3204 List.nil(), 3205 elems.toList()); 3206 boxedArgs.type = new ArrayType(varargsElement, syms.arrayClass); 3207 result.append(boxedArgs); 3208 } else { 3209 if (args.length() != 1) throw new AssertionError(args); 3210 JCExpression arg = translate(args.head, parameter); 3211 anyChanges |= (arg != args.head); 3212 result.append(arg); 3213 if (!anyChanges) return _args; 3214 } 3215 return result.toList(); 3216 } 3217 3218 /** Expand a boxing or unboxing conversion if needed. */ 3219 @SuppressWarnings("unchecked") // XXX unchecked 3220 <T extends JCExpression> T boxIfNeeded(T tree, Type type) { 3221 boolean havePrimitive = tree.type.isPrimitive(); 3222 if (havePrimitive == type.isPrimitive()) 3223 return tree; 3224 if (havePrimitive) { 3225 Type unboxedTarget = types.unboxedType(type); 3226 if (!unboxedTarget.hasTag(NONE)) { 3227 if (!types.isSubtype(tree.type, unboxedTarget)) //e.g. Character c = 89; 3228 tree.type = unboxedTarget.constType(tree.type.constValue()); 3229 return (T)boxPrimitive(tree, types.erasure(type)); 3230 } else { 3231 tree = (T)boxPrimitive(tree); 3232 } 3233 } else { 3234 tree = (T)unbox(tree, type); 3235 } 3236 return tree; 3237 } 3238 3239 /** Box up a single primitive expression. */ 3240 JCExpression boxPrimitive(JCExpression tree) { 3241 return boxPrimitive(tree, types.boxedClass(tree.type).type); 3242 } 3243 3244 /** Box up a single primitive expression. */ 3245 JCExpression boxPrimitive(JCExpression tree, Type box) { 3246 make_at(tree.pos()); 3247 Symbol valueOfSym = lookupMethod(tree.pos(), 3248 names.valueOf, 3249 box, 3250 List.<Type>nil() 3251 .prepend(tree.type)); 3252 return make.App(make.QualIdent(valueOfSym), List.of(tree)); 3253 } 3254 3255 /** Unbox an object to a primitive value. */ 3256 JCExpression unbox(JCExpression tree, Type primitive) { 3257 Type unboxedType = types.unboxedType(tree.type); 3258 if (unboxedType.hasTag(NONE)) { 3259 unboxedType = primitive; 3260 if (!unboxedType.isPrimitive()) 3261 throw new AssertionError(unboxedType); 3262 make_at(tree.pos()); 3263 tree = make.TypeCast(types.boxedClass(unboxedType).type, tree); 3264 } else { 3265 // There must be a conversion from unboxedType to primitive. 3266 if (!types.isSubtype(unboxedType, primitive)) 3267 throw new AssertionError(tree); 3268 } 3269 make_at(tree.pos()); 3270 Symbol valueSym = lookupMethod(tree.pos(), 3271 unboxedType.tsym.name.append(names.Value), // x.intValue() 3272 tree.type, 3273 List.nil()); 3274 return make.App(make.Select(tree, valueSym)); 3275 } 3276 3277 /** Visitor method for parenthesized expressions. 3278 * If the subexpression has changed, omit the parens. 3279 */ 3280 public void visitParens(JCParens tree) { 3281 JCTree expr = translate(tree.expr); 3282 result = ((expr == tree.expr) ? tree : expr); 3283 } 3284 3285 public void visitIndexed(JCArrayAccess tree) { 3286 tree.indexed = translate(tree.indexed); 3287 tree.index = translate(tree.index, syms.intType); 3288 result = tree; 3289 } 3290 3291 public void visitAssign(JCAssign tree) { 3292 tree.lhs = translate(tree.lhs, tree); 3293 tree.rhs = translate(tree.rhs, tree.lhs.type); 3294 3295 // If translated left hand side is an Apply, we are 3296 // seeing an access method invocation. In this case, append 3297 // right hand side as last argument of the access method. 3298 if (tree.lhs.hasTag(APPLY)) { 3299 JCMethodInvocation app = (JCMethodInvocation)tree.lhs; 3300 app.args = List.of(tree.rhs).prependList(app.args); 3301 result = app; 3302 } else { 3303 result = tree; 3304 } 3305 } 3306 3307 public void visitAssignop(final JCAssignOp tree) { 3308 final boolean boxingReq = !tree.lhs.type.isPrimitive() && 3309 tree.operator.type.getReturnType().isPrimitive(); 3310 3311 AssignopDependencyScanner depScanner = new AssignopDependencyScanner(tree); 3312 depScanner.scan(tree.rhs); 3313 3314 if (boxingReq || depScanner.dependencyFound) { 3315 // boxing required; need to rewrite as x = (unbox typeof x)(x op y); 3316 // or if x == (typeof x)z then z = (unbox typeof x)((typeof x)z op y) 3317 // (but without recomputing x) 3318 JCTree newTree = abstractLval(tree.lhs, lhs -> { 3319 Tag newTag = tree.getTag().noAssignOp(); 3320 // Erasure (TransTypes) can change the type of 3321 // tree.lhs. However, we can still get the 3322 // unerased type of tree.lhs as it is stored 3323 // in tree.type in Attr. 3324 OperatorSymbol newOperator = operators.resolveBinary(tree, 3325 newTag, 3326 tree.type, 3327 tree.rhs.type); 3328 //Need to use the "lhs" at two places, once on the future left hand side 3329 //and once in the future binary operator. But further processing may change 3330 //the components of the tree in place (see visitSelect for e.g. <Class>.super.<ident>), 3331 //so cloning the tree to avoid interference between the uses: 3332 JCExpression expr = (JCExpression) lhs.clone(); 3333 if (expr.type != tree.type) 3334 expr = make.TypeCast(tree.type, expr); 3335 JCBinary opResult = make.Binary(newTag, expr, tree.rhs); 3336 opResult.operator = newOperator; 3337 opResult.type = newOperator.type.getReturnType(); 3338 JCExpression newRhs = boxingReq ? 3339 make.TypeCast(types.unboxedType(tree.type), opResult) : 3340 opResult; 3341 return make.Assign(lhs, newRhs).setType(tree.type); 3342 }); 3343 result = translate(newTree); 3344 return; 3345 } 3346 tree.lhs = translate(tree.lhs, tree); 3347 tree.rhs = translate(tree.rhs, tree.operator.type.getParameterTypes().tail.head); 3348 3349 // If translated left hand side is an Apply, we are 3350 // seeing an access method invocation. In this case, append 3351 // right hand side as last argument of the access method. 3352 if (tree.lhs.hasTag(APPLY)) { 3353 JCMethodInvocation app = (JCMethodInvocation)tree.lhs; 3354 // if operation is a += on strings, 3355 // make sure to convert argument to string 3356 JCExpression rhs = tree.operator.opcode == string_add 3357 ? makeString(tree.rhs) 3358 : tree.rhs; 3359 app.args = List.of(rhs).prependList(app.args); 3360 result = app; 3361 } else { 3362 result = tree; 3363 } 3364 } 3365 3366 class AssignopDependencyScanner extends TreeScanner { 3367 3368 Symbol sym; 3369 boolean dependencyFound = false; 3370 3371 AssignopDependencyScanner(JCAssignOp tree) { 3372 this.sym = TreeInfo.symbol(tree.lhs); 3373 } 3374 3375 @Override 3376 public void scan(JCTree tree) { 3377 if (tree != null && sym != null) { 3378 tree.accept(this); 3379 } 3380 } 3381 3382 @Override 3383 public void visitAssignop(JCAssignOp tree) { 3384 if (TreeInfo.symbol(tree.lhs) == sym) { 3385 dependencyFound = true; 3386 return; 3387 } 3388 super.visitAssignop(tree); 3389 } 3390 3391 @Override 3392 public void visitUnary(JCUnary tree) { 3393 if (TreeInfo.symbol(tree.arg) == sym) { 3394 dependencyFound = true; 3395 return; 3396 } 3397 super.visitUnary(tree); 3398 } 3399 } 3400 3401 /** Lower a tree of the form e++ or e-- where e is an object type */ 3402 JCExpression lowerBoxedPostop(final JCUnary tree) { 3403 // translate to tmp1=lval(e); tmp2=tmp1; tmp1 OP 1; tmp2 3404 // or 3405 // translate to tmp1=lval(e); tmp2=tmp1; (typeof tree)tmp1 OP 1; tmp2 3406 // where OP is += or -= 3407 final boolean cast = TreeInfo.skipParens(tree.arg).hasTag(TYPECAST); 3408 return abstractLval(tree.arg, tmp1 -> abstractRval(tmp1, tree.arg.type, tmp2 -> { 3409 Tag opcode = (tree.hasTag(POSTINC)) 3410 ? PLUS_ASG : MINUS_ASG; 3411 //"tmp1" and "tmp2" may refer to the same instance 3412 //(for e.g. <Class>.super.<ident>). But further processing may 3413 //change the components of the tree in place (see visitSelect), 3414 //so cloning the tree to avoid interference between the two uses: 3415 JCExpression lhs = (JCExpression)tmp1.clone(); 3416 lhs = cast 3417 ? make.TypeCast(tree.arg.type, lhs) 3418 : lhs; 3419 JCExpression update = makeAssignop(opcode, 3420 lhs, 3421 make.Literal(1)); 3422 return makeComma(update, tmp2); 3423 })); 3424 } 3425 3426 public void visitUnary(JCUnary tree) { 3427 boolean isUpdateOperator = tree.getTag().isIncOrDecUnaryOp(); 3428 if (isUpdateOperator && !tree.arg.type.isPrimitive()) { 3429 switch(tree.getTag()) { 3430 case PREINC: // ++ e 3431 // translate to e += 1 3432 case PREDEC: // -- e 3433 // translate to e -= 1 3434 { 3435 JCTree.Tag opcode = (tree.hasTag(PREINC)) 3436 ? PLUS_ASG : MINUS_ASG; 3437 JCAssignOp newTree = makeAssignop(opcode, 3438 tree.arg, 3439 make.Literal(1)); 3440 result = translate(newTree, tree.type); 3441 return; 3442 } 3443 case POSTINC: // e ++ 3444 case POSTDEC: // e -- 3445 { 3446 result = translate(lowerBoxedPostop(tree), tree.type); 3447 return; 3448 } 3449 } 3450 throw new AssertionError(tree); 3451 } 3452 3453 tree.arg = boxIfNeeded(translate(tree.arg, tree), tree.type); 3454 3455 if (tree.hasTag(NOT) && tree.arg.type.constValue() != null) { 3456 tree.type = cfolder.fold1(bool_not, tree.arg.type); 3457 } 3458 3459 // If translated left hand side is an Apply, we are 3460 // seeing an access method invocation. In this case, return 3461 // that access method invocation as result. 3462 if (isUpdateOperator && tree.arg.hasTag(APPLY)) { 3463 result = tree.arg; 3464 } else { 3465 result = tree; 3466 } 3467 } 3468 3469 public void visitBinary(JCBinary tree) { 3470 List<Type> formals = tree.operator.type.getParameterTypes(); 3471 JCTree lhs = tree.lhs = translate(tree.lhs, formals.head); 3472 switch (tree.getTag()) { 3473 case OR: 3474 if (isTrue(lhs)) { 3475 result = lhs; 3476 return; 3477 } 3478 if (isFalse(lhs)) { 3479 result = translate(tree.rhs, formals.tail.head); 3480 return; 3481 } 3482 break; 3483 case AND: 3484 if (isFalse(lhs)) { 3485 result = lhs; 3486 return; 3487 } 3488 if (isTrue(lhs)) { 3489 result = translate(tree.rhs, formals.tail.head); 3490 return; 3491 } 3492 break; 3493 } 3494 tree.rhs = translate(tree.rhs, formals.tail.head); 3495 result = tree; 3496 } 3497 3498 public void visitIdent(JCIdent tree) { 3499 result = access(tree.sym, tree, enclOp, false); 3500 } 3501 3502 /** Translate away the foreach loop. */ 3503 public void visitForeachLoop(JCEnhancedForLoop tree) { 3504 if (types.elemtype(tree.expr.type) == null) 3505 visitIterableForeachLoop(tree); 3506 else 3507 visitArrayForeachLoop(tree); 3508 } 3509 // where 3510 /** 3511 * A statement of the form 3512 * 3513 * <pre> 3514 * for ( T v : arrayexpr ) stmt; 3515 * </pre> 3516 * 3517 * (where arrayexpr is of an array type) gets translated to 3518 * 3519 * <pre>{@code 3520 * for ( { arraytype #arr = arrayexpr; 3521 * int #len = array.length; 3522 * int #i = 0; }; 3523 * #i < #len; i$++ ) { 3524 * T v = arr$[#i]; 3525 * stmt; 3526 * } 3527 * }</pre> 3528 * 3529 * where #arr, #len, and #i are freshly named synthetic local variables. 3530 */ 3531 private void visitArrayForeachLoop(JCEnhancedForLoop tree) { 3532 make_at(tree.expr.pos()); 3533 VarSymbol arraycache = new VarSymbol(SYNTHETIC, 3534 names.fromString("arr" + target.syntheticNameChar()), 3535 tree.expr.type, 3536 currentMethodSym); 3537 JCStatement arraycachedef = make.VarDef(arraycache, tree.expr); 3538 VarSymbol lencache = new VarSymbol(SYNTHETIC, 3539 names.fromString("len" + target.syntheticNameChar()), 3540 syms.intType, 3541 currentMethodSym); 3542 JCStatement lencachedef = make. 3543 VarDef(lencache, make.Select(make.Ident(arraycache), syms.lengthVar)); 3544 VarSymbol index = new VarSymbol(SYNTHETIC, 3545 names.fromString("i" + target.syntheticNameChar()), 3546 syms.intType, 3547 currentMethodSym); 3548 3549 JCVariableDecl indexdef = make.VarDef(index, make.Literal(INT, 0)); 3550 indexdef.init.type = indexdef.type = syms.intType.constType(0); 3551 3552 List<JCStatement> loopinit = List.of(arraycachedef, lencachedef, indexdef); 3553 JCBinary cond = makeBinary(LT, make.Ident(index), make.Ident(lencache)); 3554 3555 JCExpressionStatement step = make.Exec(makeUnary(PREINC, make.Ident(index))); 3556 3557 Type elemtype = types.elemtype(tree.expr.type); 3558 JCExpression loopvarinit = make.Indexed(make.Ident(arraycache), 3559 make.Ident(index)).setType(elemtype); 3560 JCVariableDecl loopvardef = (JCVariableDecl)make.VarDef(tree.var.mods, 3561 tree.var.name, 3562 tree.var.vartype, 3563 loopvarinit).setType(tree.var.type); 3564 loopvardef.sym = tree.var.sym; 3565 JCBlock body = make. 3566 Block(0, List.of(loopvardef, tree.body)); 3567 3568 result = translate(make. 3569 ForLoop(loopinit, 3570 cond, 3571 List.of(step), 3572 body)); 3573 patchTargets(body, tree, result); 3574 } 3575 /** Patch up break and continue targets. */ 3576 private void patchTargets(JCTree body, final JCTree src, final JCTree dest) { 3577 class Patcher extends TreeScanner { 3578 public void visitBreak(JCBreak tree) { 3579 if (tree.target == src) 3580 tree.target = dest; 3581 } 3582 public void visitYield(JCYield tree) { 3583 if (tree.target == src) 3584 tree.target = dest; 3585 scan(tree.value); 3586 } 3587 public void visitContinue(JCContinue tree) { 3588 if (tree.target == src) 3589 tree.target = dest; 3590 } 3591 public void visitClassDef(JCClassDecl tree) {} 3592 } 3593 new Patcher().scan(body); 3594 } 3595 /** 3596 * A statement of the form 3597 * 3598 * <pre> 3599 * for ( T v : coll ) stmt ; 3600 * </pre> 3601 * 3602 * (where coll implements {@code Iterable<? extends T>}) gets translated to 3603 * 3604 * <pre>{@code 3605 * for ( Iterator<? extends T> #i = coll.iterator(); #i.hasNext(); ) { 3606 * T v = (T) #i.next(); 3607 * stmt; 3608 * } 3609 * }</pre> 3610 * 3611 * where #i is a freshly named synthetic local variable. 3612 */ 3613 private void visitIterableForeachLoop(JCEnhancedForLoop tree) { 3614 make_at(tree.expr.pos()); 3615 Type iteratorTarget = syms.objectType; 3616 Type iterableType = types.asSuper(types.cvarUpperBound(tree.expr.type), 3617 syms.iterableType.tsym); 3618 if (iterableType.getTypeArguments().nonEmpty()) 3619 iteratorTarget = types.erasure(iterableType.getTypeArguments().head); 3620 tree.expr.type = types.erasure(types.skipTypeVars(tree.expr.type, false)); 3621 tree.expr = transTypes.coerce(attrEnv, tree.expr, types.erasure(iterableType)); 3622 Symbol iterator = lookupMethod(tree.expr.pos(), 3623 names.iterator, 3624 tree.expr.type, 3625 List.nil()); 3626 Assert.check(types.isSameType(types.erasure(types.asSuper(iterator.type.getReturnType(), syms.iteratorType.tsym)), types.erasure(syms.iteratorType))); 3627 VarSymbol itvar = new VarSymbol(SYNTHETIC, names.fromString("i" + target.syntheticNameChar()), 3628 types.erasure(syms.iteratorType), 3629 currentMethodSym); 3630 3631 JCStatement init = make. 3632 VarDef(itvar, make.App(make.Select(tree.expr, iterator) 3633 .setType(types.erasure(iterator.type)))); 3634 3635 Symbol hasNext = lookupMethod(tree.expr.pos(), 3636 names.hasNext, 3637 itvar.type, 3638 List.nil()); 3639 JCMethodInvocation cond = make.App(make.Select(make.Ident(itvar), hasNext)); 3640 Symbol next = lookupMethod(tree.expr.pos(), 3641 names.next, 3642 itvar.type, 3643 List.nil()); 3644 JCExpression vardefinit = make.App(make.Select(make.Ident(itvar), next)); 3645 if (tree.var.type.isPrimitive()) 3646 vardefinit = make.TypeCast(types.cvarUpperBound(iteratorTarget), vardefinit); 3647 else 3648 vardefinit = make.TypeCast(tree.var.type, vardefinit); 3649 JCVariableDecl indexDef = (JCVariableDecl)make.VarDef(tree.var.mods, 3650 tree.var.name, 3651 tree.var.vartype, 3652 vardefinit).setType(tree.var.type); 3653 indexDef.sym = tree.var.sym; 3654 JCBlock body = make.Block(0, List.of(indexDef, tree.body)); 3655 body.endpos = TreeInfo.endPos(tree.body); 3656 result = translate(make. 3657 ForLoop(List.of(init), 3658 cond, 3659 List.nil(), 3660 body)); 3661 patchTargets(body, tree, result); 3662 } 3663 3664 public void visitVarDef(JCVariableDecl tree) { 3665 MethodSymbol oldMethodSym = currentMethodSym; 3666 tree.mods = translate(tree.mods); 3667 tree.vartype = translate(tree.vartype); 3668 if (currentMethodSym == null) { 3669 // A class or instance field initializer. 3670 currentMethodSym = 3671 new MethodSymbol((tree.mods.flags&STATIC) | BLOCK, 3672 names.empty, null, 3673 currentClass); 3674 } 3675 if (tree.init != null) tree.init = translate(tree.init, tree.type); 3676 result = tree; 3677 currentMethodSym = oldMethodSym; 3678 } 3679 3680 public void visitBlock(JCBlock tree) { 3681 MethodSymbol oldMethodSym = currentMethodSym; 3682 if (currentMethodSym == null) { 3683 // Block is a static or instance initializer. 3684 currentMethodSym = 3685 new MethodSymbol(tree.flags | BLOCK, 3686 names.empty, null, 3687 currentClass); 3688 } 3689 super.visitBlock(tree); 3690 currentMethodSym = oldMethodSym; 3691 } 3692 3693 public void visitDoLoop(JCDoWhileLoop tree) { 3694 tree.body = translate(tree.body); 3695 tree.cond = translate(tree.cond, syms.booleanType); 3696 result = tree; 3697 } 3698 3699 public void visitWhileLoop(JCWhileLoop tree) { 3700 tree.cond = translate(tree.cond, syms.booleanType); 3701 tree.body = translate(tree.body); 3702 result = tree; 3703 } 3704 3705 public void visitForLoop(JCForLoop tree) { 3706 tree.init = translate(tree.init); 3707 if (tree.cond != null) 3708 tree.cond = translate(tree.cond, syms.booleanType); 3709 tree.step = translate(tree.step); 3710 tree.body = translate(tree.body); 3711 result = tree; 3712 } 3713 3714 public void visitReturn(JCReturn tree) { 3715 if (tree.expr != null) 3716 tree.expr = translate(tree.expr, 3717 types.erasure(currentMethodDef 3718 .restype.type)); 3719 result = tree; 3720 } 3721 3722 public void visitSwitch(JCSwitch tree) { 3723 List<JCCase> cases = tree.patternSwitch ? addDefaultIfNeeded(tree.patternSwitch, 3724 tree.wasEnumSelector, 3725 tree.cases) 3726 : tree.cases; 3727 handleSwitch(tree, tree.selector, cases); 3728 } 3729 3730 @Override 3731 public void visitSwitchExpression(JCSwitchExpression tree) { 3732 List<JCCase> cases = addDefaultIfNeeded(tree.patternSwitch, tree.wasEnumSelector, tree.cases); 3733 handleSwitch(tree, tree.selector, cases); 3734 } 3735 3736 private List<JCCase> addDefaultIfNeeded(boolean patternSwitch, boolean wasEnumSelector, 3737 List<JCCase> cases) { 3738 if (cases.stream().flatMap(c -> c.labels.stream()).noneMatch(p -> p.hasTag(Tag.DEFAULTCASELABEL))) { 3739 boolean matchException = useMatchException; 3740 matchException |= patternSwitch && !wasEnumSelector; 3741 Type exception = matchException ? syms.matchExceptionType 3742 : syms.incompatibleClassChangeErrorType; 3743 List<JCExpression> params = matchException ? List.of(makeNull(), makeNull()) 3744 : List.nil(); 3745 JCThrow thr = make.Throw(makeNewClass(exception, params)); 3746 JCCase c = make.Case(JCCase.STATEMENT, List.of(make.DefaultCaseLabel()), null, List.of(thr), null); 3747 cases = cases.prepend(c); 3748 } 3749 3750 return cases; 3751 } 3752 3753 private void handleSwitch(JCTree tree, JCExpression selector, List<JCCase> cases) { 3754 //expand multiple label cases: 3755 ListBuffer<JCCase> convertedCases = new ListBuffer<>(); 3756 3757 for (JCCase c : cases) { 3758 switch (c.labels.size()) { 3759 case 0: //default 3760 case 1: //single label 3761 convertedCases.append(c); 3762 break; 3763 default: //multiple labels, expand: 3764 //case C1, C2, C3: ... 3765 //=> 3766 //case C1: 3767 //case C2: 3768 //case C3: ... 3769 List<JCCaseLabel> patterns = c.labels; 3770 while (patterns.tail.nonEmpty()) { 3771 convertedCases.append(make_at(c.pos()).Case(JCCase.STATEMENT, 3772 List.of(patterns.head), 3773 null, 3774 List.nil(), 3775 null)); 3776 patterns = patterns.tail; 3777 } 3778 c.labels = patterns; 3779 convertedCases.append(c); 3780 break; 3781 } 3782 } 3783 3784 for (JCCase c : convertedCases) { 3785 if (c.caseKind == JCCase.RULE && c.completesNormally) { 3786 JCBreak b = make.at(TreeInfo.endPos(c.stats.last())).Break(null); 3787 b.target = tree; 3788 c.stats = c.stats.append(b); 3789 } 3790 } 3791 3792 cases = convertedCases.toList(); 3793 3794 Type selsuper = types.supertype(selector.type); 3795 boolean enumSwitch = selsuper != null && 3796 (selector.type.tsym.flags() & ENUM) != 0; 3797 boolean stringSwitch = selsuper != null && 3798 types.isSameType(selector.type, syms.stringType); 3799 boolean boxedSwitch = !enumSwitch && !stringSwitch && !selector.type.isPrimitive(); 3800 selector = translate(selector, selector.type); 3801 cases = translateCases(cases); 3802 if (tree.hasTag(SWITCH)) { 3803 ((JCSwitch) tree).selector = selector; 3804 ((JCSwitch) tree).cases = cases; 3805 } else if (tree.hasTag(SWITCH_EXPRESSION)) { 3806 ((JCSwitchExpression) tree).selector = selector; 3807 ((JCSwitchExpression) tree).cases = cases; 3808 } else { 3809 Assert.error(); 3810 } 3811 if (enumSwitch) { 3812 result = visitEnumSwitch(tree, selector, cases); 3813 } else if (stringSwitch) { 3814 result = visitStringSwitch(tree, selector, cases); 3815 } else if (boxedSwitch) { 3816 //An switch over boxed primitive. Pattern matching switches are already translated 3817 //by TransPatterns, so all non-primitive types are only boxed primitives: 3818 result = visitBoxedPrimitiveSwitch(tree, selector, cases); 3819 } else { 3820 result = tree; 3821 } 3822 } 3823 3824 public JCTree visitEnumSwitch(JCTree tree, JCExpression selector, List<JCCase> cases) { 3825 TypeSymbol enumSym = selector.type.tsym; 3826 EnumMapping map = mapForEnum(tree.pos(), enumSym); 3827 make_at(tree.pos()); 3828 Symbol ordinalMethod = lookupMethod(tree.pos(), 3829 names.ordinal, 3830 selector.type, 3831 List.nil()); 3832 JCExpression newSelector; 3833 3834 if (cases.stream().anyMatch(c -> TreeInfo.isNullCaseLabel(c.labels.head))) { 3835 //for enum switches with case null, do: 3836 //switch ($selector != null ? $mapVar[$selector.ordinal()] : -1) {...} 3837 //replacing case null with case -1: 3838 VarSymbol dollar_s = new VarSymbol(FINAL|SYNTHETIC, 3839 names.fromString("s" + tree.pos + this.target.syntheticNameChar()), 3840 selector.type, 3841 currentMethodSym); 3842 JCStatement var = make.at(tree.pos()).VarDef(dollar_s, selector).setType(dollar_s.type); 3843 newSelector = map.switchValue( 3844 make.App(make.Select(make.Ident(dollar_s), 3845 ordinalMethod))); 3846 newSelector = 3847 make.LetExpr(List.of(var), 3848 make.Conditional(makeBinary(NE, make.Ident(dollar_s), makeNull()), 3849 newSelector, 3850 makeLit(syms.intType, -1)) 3851 .setType(newSelector.type)) 3852 .setType(newSelector.type); 3853 } else { 3854 newSelector = map.switchValue( 3855 make.App(make.Select(selector, 3856 ordinalMethod))); 3857 } 3858 ListBuffer<JCCase> newCases = new ListBuffer<>(); 3859 for (JCCase c : cases) { 3860 if (c.labels.head.hasTag(CONSTANTCASELABEL)) { 3861 JCExpression pat; 3862 if (TreeInfo.isNullCaseLabel(c.labels.head)) { 3863 pat = makeLit(syms.intType, -1); 3864 } else { 3865 VarSymbol label = (VarSymbol)TreeInfo.symbol(((JCConstantCaseLabel) c.labels.head).expr); 3866 pat = map.caseValue(label); 3867 } 3868 newCases.append(make.Case(JCCase.STATEMENT, List.of(make.ConstantCaseLabel(pat)), null, c.stats, null)); 3869 } else { 3870 newCases.append(c); 3871 } 3872 } 3873 JCTree enumSwitch; 3874 if (tree.hasTag(SWITCH)) { 3875 enumSwitch = make.Switch(newSelector, newCases.toList()); 3876 } else if (tree.hasTag(SWITCH_EXPRESSION)) { 3877 enumSwitch = make.SwitchExpression(newSelector, newCases.toList()); 3878 enumSwitch.setType(tree.type); 3879 } else { 3880 Assert.error(); 3881 throw new AssertionError(); 3882 } 3883 patchTargets(enumSwitch, tree, enumSwitch); 3884 return enumSwitch; 3885 } 3886 3887 public JCTree visitStringSwitch(JCTree tree, JCExpression selector, List<JCCase> caseList) { 3888 int alternatives = caseList.size(); 3889 3890 if (alternatives == 0) { // Strange but legal possibility (only legal for switch statement) 3891 return make.at(tree.pos()).Exec(attr.makeNullCheck(selector)); 3892 } else { 3893 /* 3894 * The general approach used is to translate a single 3895 * string switch statement into a series of two chained 3896 * switch statements: the first a synthesized statement 3897 * switching on the argument string's hash value and 3898 * computing a string's position in the list of original 3899 * case labels, if any, followed by a second switch on the 3900 * computed integer value. The second switch has the same 3901 * code structure as the original string switch statement 3902 * except that the string case labels are replaced with 3903 * positional integer constants starting at 0. 3904 * 3905 * The first switch statement can be thought of as an 3906 * inlined map from strings to their position in the case 3907 * label list. An alternate implementation would use an 3908 * actual Map for this purpose, as done for enum switches. 3909 * 3910 * With some additional effort, it would be possible to 3911 * use a single switch statement on the hash code of the 3912 * argument, but care would need to be taken to preserve 3913 * the proper control flow in the presence of hash 3914 * collisions and other complications, such as 3915 * fallthroughs. Switch statements with one or two 3916 * alternatives could also be specially translated into 3917 * if-then statements to omit the computation of the hash 3918 * code. 3919 * 3920 * The generated code assumes that the hashing algorithm 3921 * of String is the same in the compilation environment as 3922 * in the environment the code will run in. The string 3923 * hashing algorithm in the SE JDK has been unchanged 3924 * since at least JDK 1.2. Since the algorithm has been 3925 * specified since that release as well, it is very 3926 * unlikely to be changed in the future. 3927 * 3928 * Different hashing algorithms, such as the length of the 3929 * strings or a perfect hashing algorithm over the 3930 * particular set of case labels, could potentially be 3931 * used instead of String.hashCode. 3932 */ 3933 3934 ListBuffer<JCStatement> stmtList = new ListBuffer<>(); 3935 3936 // Map from String case labels to their original position in 3937 // the list of case labels. 3938 Map<String, Integer> caseLabelToPosition = new LinkedHashMap<>(alternatives + 1, 1.0f); 3939 3940 // Map of hash codes to the string case labels having that hashCode. 3941 Map<Integer, Set<String>> hashToString = new LinkedHashMap<>(alternatives + 1, 1.0f); 3942 3943 int casePosition = 0; 3944 JCCase nullCase = null; 3945 int nullCaseLabel = -1; 3946 3947 for(JCCase oneCase : caseList) { 3948 if (oneCase.labels.head.hasTag(CONSTANTCASELABEL)) { 3949 if (TreeInfo.isNullCaseLabel(oneCase.labels.head)) { 3950 nullCase = oneCase; 3951 nullCaseLabel = casePosition; 3952 } else { 3953 JCExpression expression = ((JCConstantCaseLabel) oneCase.labels.head).expr; 3954 String labelExpr = (String) expression.type.constValue(); 3955 Integer mapping = caseLabelToPosition.put(labelExpr, casePosition); 3956 Assert.checkNull(mapping); 3957 int hashCode = labelExpr.hashCode(); 3958 3959 Set<String> stringSet = hashToString.get(hashCode); 3960 if (stringSet == null) { 3961 stringSet = new LinkedHashSet<>(1, 1.0f); 3962 stringSet.add(labelExpr); 3963 hashToString.put(hashCode, stringSet); 3964 } else { 3965 boolean added = stringSet.add(labelExpr); 3966 Assert.check(added); 3967 } 3968 } 3969 } 3970 casePosition++; 3971 } 3972 3973 // Synthesize a switch statement that has the effect of 3974 // mapping from a string to the integer position of that 3975 // string in the list of case labels. This is done by 3976 // switching on the hashCode of the string followed by an 3977 // if-then-else chain comparing the input for equality 3978 // with all the case labels having that hash value. 3979 3980 /* 3981 * s$ = top of stack; 3982 * tmp$ = -1; 3983 * switch($s.hashCode()) { 3984 * case caseLabel.hashCode: 3985 * if (s$.equals("caseLabel_1") 3986 * tmp$ = caseLabelToPosition("caseLabel_1"); 3987 * else if (s$.equals("caseLabel_2")) 3988 * tmp$ = caseLabelToPosition("caseLabel_2"); 3989 * ... 3990 * break; 3991 * ... 3992 * } 3993 */ 3994 3995 VarSymbol dollar_s = new VarSymbol(FINAL|SYNTHETIC, 3996 names.fromString("s" + tree.pos + target.syntheticNameChar()), 3997 syms.stringType, 3998 currentMethodSym); 3999 stmtList.append(make.at(tree.pos()).VarDef(dollar_s, selector).setType(dollar_s.type)); 4000 4001 VarSymbol dollar_tmp = new VarSymbol(SYNTHETIC, 4002 names.fromString("tmp" + tree.pos + target.syntheticNameChar()), 4003 syms.intType, 4004 currentMethodSym); 4005 JCVariableDecl dollar_tmp_def = 4006 (JCVariableDecl)make.VarDef(dollar_tmp, make.Literal(INT, -1)).setType(dollar_tmp.type); 4007 dollar_tmp_def.init.type = dollar_tmp.type = syms.intType; 4008 stmtList.append(dollar_tmp_def); 4009 ListBuffer<JCCase> caseBuffer = new ListBuffer<>(); 4010 // hashCode will trigger nullcheck on original switch expression 4011 JCMethodInvocation hashCodeCall = makeCall(make.Ident(dollar_s), 4012 names.hashCode, 4013 List.nil()).setType(syms.intType); 4014 JCSwitch switch1 = make.Switch(hashCodeCall, 4015 caseBuffer.toList()); 4016 for(Map.Entry<Integer, Set<String>> entry : hashToString.entrySet()) { 4017 int hashCode = entry.getKey(); 4018 Set<String> stringsWithHashCode = entry.getValue(); 4019 Assert.check(stringsWithHashCode.size() >= 1); 4020 4021 JCStatement elsepart = null; 4022 for(String caseLabel : stringsWithHashCode ) { 4023 JCMethodInvocation stringEqualsCall = makeCall(make.Ident(dollar_s), 4024 names.equals, 4025 List.of(make.Literal(caseLabel))); 4026 elsepart = make.If(stringEqualsCall, 4027 make.Exec(make.Assign(make.Ident(dollar_tmp), 4028 make.Literal(caseLabelToPosition.get(caseLabel))). 4029 setType(dollar_tmp.type)), 4030 elsepart); 4031 } 4032 4033 ListBuffer<JCStatement> lb = new ListBuffer<>(); 4034 JCBreak breakStmt = make.Break(null); 4035 breakStmt.target = switch1; 4036 lb.append(elsepart).append(breakStmt); 4037 4038 caseBuffer.append(make.Case(JCCase.STATEMENT, 4039 List.of(make.ConstantCaseLabel(make.Literal(hashCode))), 4040 null, 4041 lb.toList(), 4042 null)); 4043 } 4044 4045 switch1.cases = caseBuffer.toList(); 4046 4047 if (nullCase != null) { 4048 stmtList.append(make.If(makeBinary(NE, make.Ident(dollar_s), makeNull()), switch1, make.Exec(make.Assign(make.Ident(dollar_tmp), 4049 make.Literal(nullCaseLabel)). 4050 setType(dollar_tmp.type))).setType(syms.intType)); 4051 } else { 4052 stmtList.append(switch1); 4053 } 4054 4055 // Make isomorphic switch tree replacing string labels 4056 // with corresponding integer ones from the label to 4057 // position map. 4058 4059 ListBuffer<JCCase> lb = new ListBuffer<>(); 4060 for(JCCase oneCase : caseList ) { 4061 boolean isDefault = !oneCase.labels.head.hasTag(CONSTANTCASELABEL); 4062 JCExpression caseExpr; 4063 if (isDefault) 4064 caseExpr = null; 4065 else if (oneCase == nullCase) { 4066 caseExpr = make.Literal(nullCaseLabel); 4067 } else { 4068 JCExpression expression = ((JCConstantCaseLabel) oneCase.labels.head).expr; 4069 String name = (String) TreeInfo.skipParens(expression) 4070 .type.constValue(); 4071 caseExpr = make.Literal(caseLabelToPosition.get(name)); 4072 } 4073 4074 lb.append(make.Case(JCCase.STATEMENT, caseExpr == null ? List.of(make.DefaultCaseLabel()) 4075 : List.of(make.ConstantCaseLabel(caseExpr)), 4076 null, 4077 oneCase.stats, null)); 4078 } 4079 4080 if (tree.hasTag(SWITCH)) { 4081 JCSwitch switch2 = make.Switch(make.Ident(dollar_tmp), lb.toList()); 4082 // Rewire up old unlabeled break statements to the 4083 // replacement switch being created. 4084 patchTargets(switch2, tree, switch2); 4085 4086 stmtList.append(switch2); 4087 4088 JCBlock res = make.Block(0L, stmtList.toList()); 4089 res.endpos = TreeInfo.endPos(tree); 4090 return res; 4091 } else { 4092 JCSwitchExpression switch2 = make.SwitchExpression(make.Ident(dollar_tmp), lb.toList()); 4093 4094 // Rewire up old unlabeled break statements to the 4095 // replacement switch being created. 4096 patchTargets(switch2, tree, switch2); 4097 4098 switch2.setType(tree.type); 4099 4100 LetExpr res = make.LetExpr(stmtList.toList(), switch2); 4101 4102 res.needsCond = true; 4103 res.setType(tree.type); 4104 4105 return res; 4106 } 4107 } 4108 } 4109 4110 private JCTree visitBoxedPrimitiveSwitch(JCTree tree, JCExpression selector, List<JCCase> cases) { 4111 JCExpression newSelector; 4112 4113 if (cases.stream().anyMatch(c -> TreeInfo.isNullCaseLabel(c.labels.head))) { 4114 //a switch over a boxed primitive, with a null case. Pick two constants that are 4115 //not used by any branch in the case (c1 and c2), close to other constants that are 4116 //used in the switch. Then do: 4117 //switch ($selector != null ? $selector != c1 ? $selector : c2 : c1) {...} 4118 //replacing case null with case c1 4119 Set<Integer> constants = new LinkedHashSet<>(); 4120 JCCase nullCase = null; 4121 4122 for (JCCase c : cases) { 4123 if (TreeInfo.isNullCaseLabel(c.labels.head)) { 4124 nullCase = c; 4125 } else if (!c.labels.head.hasTag(DEFAULTCASELABEL)) { 4126 constants.add((int) ((JCConstantCaseLabel) c.labels.head).expr.type.constValue()); 4127 } 4128 } 4129 4130 Assert.checkNonNull(nullCase); 4131 4132 int nullValue = constants.isEmpty() ? 0 : constants.iterator().next(); 4133 4134 while (constants.contains(nullValue)) nullValue++; 4135 4136 constants.add(nullValue); 4137 nullCase.labels.head = make.ConstantCaseLabel(makeLit(syms.intType, nullValue)); 4138 4139 int replacementValue = nullValue; 4140 4141 while (constants.contains(replacementValue)) replacementValue++; 4142 4143 VarSymbol dollar_s = new VarSymbol(FINAL|SYNTHETIC, 4144 names.fromString("s" + tree.pos + this.target.syntheticNameChar()), 4145 selector.type, 4146 currentMethodSym); 4147 JCStatement var = make.at(tree.pos()).VarDef(dollar_s, selector).setType(dollar_s.type); 4148 JCExpression nullValueReplacement = 4149 make.Conditional(makeBinary(NE, 4150 unbox(make.Ident(dollar_s), syms.intType), 4151 makeLit(syms.intType, nullValue)), 4152 unbox(make.Ident(dollar_s), syms.intType), 4153 makeLit(syms.intType, replacementValue)) 4154 .setType(syms.intType); 4155 JCExpression nullCheck = 4156 make.Conditional(makeBinary(NE, make.Ident(dollar_s), makeNull()), 4157 nullValueReplacement, 4158 makeLit(syms.intType, nullValue)) 4159 .setType(syms.intType); 4160 newSelector = make.LetExpr(List.of(var), nullCheck).setType(syms.intType); 4161 } else { 4162 newSelector = unbox(selector, syms.intType); 4163 } 4164 4165 if (tree.hasTag(SWITCH)) { 4166 ((JCSwitch) tree).selector = newSelector; 4167 } else { 4168 ((JCSwitchExpression) tree).selector = newSelector; 4169 } 4170 4171 return tree; 4172 } 4173 4174 @Override 4175 public void visitBreak(JCBreak tree) { 4176 result = tree; 4177 } 4178 4179 @Override 4180 public void visitYield(JCYield tree) { 4181 tree.value = translate(tree.value, tree.target.type); 4182 result = tree; 4183 } 4184 4185 public void visitNewArray(JCNewArray tree) { 4186 tree.elemtype = translate(tree.elemtype); 4187 for (List<JCExpression> t = tree.dims; t.tail != null; t = t.tail) 4188 if (t.head != null) t.head = translate(t.head, syms.intType); 4189 tree.elems = translate(tree.elems, types.elemtype(tree.type)); 4190 result = tree; 4191 } 4192 4193 public void visitSelect(JCFieldAccess tree) { 4194 // need to special case-access of the form C.super.x 4195 // these will always need an access method, unless C 4196 // is a default interface subclassed by the current class. 4197 boolean qualifiedSuperAccess = 4198 tree.selected.hasTag(SELECT) && 4199 TreeInfo.name(tree.selected) == names._super && 4200 !types.isDirectSuperInterface(((JCFieldAccess)tree.selected).selected.type.tsym, currentClass); 4201 tree.selected = translate(tree.selected); 4202 if (tree.name == names._class) { 4203 result = classOf(tree.selected); 4204 } 4205 else if (tree.name == names._super && 4206 types.isDirectSuperInterface(tree.selected.type.tsym, currentClass)) { 4207 //default super call!! Not a classic qualified super call 4208 TypeSymbol supSym = tree.selected.type.tsym; 4209 Assert.checkNonNull(types.asSuper(currentClass.type, supSym)); 4210 result = tree; 4211 } 4212 else if (tree.name == names._this || tree.name == names._super) { 4213 result = makeThis(tree.pos(), tree.selected.type.tsym); 4214 } 4215 else 4216 result = access(tree.sym, tree, enclOp, qualifiedSuperAccess); 4217 } 4218 4219 public void visitLetExpr(LetExpr tree) { 4220 tree.defs = translate(tree.defs); 4221 tree.expr = translate(tree.expr, tree.type); 4222 result = tree; 4223 } 4224 4225 // There ought to be nothing to rewrite here; 4226 // we don't generate code. 4227 public void visitAnnotation(JCAnnotation tree) { 4228 result = tree; 4229 } 4230 4231 @Override 4232 public void visitTry(JCTry tree) { 4233 if (tree.resources.nonEmpty()) { 4234 result = makeTwrTry(tree); 4235 return; 4236 } 4237 4238 boolean hasBody = tree.body.getStatements().nonEmpty(); 4239 boolean hasCatchers = tree.catchers.nonEmpty(); 4240 boolean hasFinally = tree.finalizer != null && 4241 tree.finalizer.getStatements().nonEmpty(); 4242 4243 if (!hasCatchers && !hasFinally) { 4244 result = translate(tree.body); 4245 return; 4246 } 4247 4248 if (!hasBody) { 4249 if (hasFinally) { 4250 result = translate(tree.finalizer); 4251 } else { 4252 result = translate(tree.body); 4253 } 4254 return; 4255 } 4256 4257 // no optimizations possible 4258 super.visitTry(tree); 4259 } 4260 4261 /************************************************************************** 4262 * main method 4263 *************************************************************************/ 4264 4265 /** Translate a toplevel class and return a list consisting of 4266 * the translated class and translated versions of all inner classes. 4267 * @param env The attribution environment current at the class definition. 4268 * We need this for resolving some additional symbols. 4269 * @param cdef The tree representing the class definition. 4270 */ 4271 public List<JCTree> translateTopLevelClass(Env<AttrContext> env, JCTree cdef, TreeMaker make) { 4272 ListBuffer<JCTree> translated = null; 4273 try { 4274 attrEnv = env; 4275 this.make = make; 4276 endPosTable = env.toplevel.endPositions; 4277 currentClass = null; 4278 currentMethodDef = null; 4279 outermostClassDef = (cdef.hasTag(CLASSDEF)) ? (JCClassDecl)cdef : null; 4280 outermostMemberDef = null; 4281 this.translated = new ListBuffer<>(); 4282 classdefs = new HashMap<>(); 4283 actualSymbols = new HashMap<>(); 4284 freevarCache = new HashMap<>(); 4285 proxies = new HashMap<>(); 4286 twrVars = WriteableScope.create(syms.noSymbol); 4287 outerThisStack = List.nil(); 4288 accessNums = new HashMap<>(); 4289 accessSyms = new HashMap<>(); 4290 accessConstrs = new HashMap<>(); 4291 accessConstrTags = List.nil(); 4292 accessed = new ListBuffer<>(); 4293 translate(cdef, (JCExpression)null); 4294 for (List<Symbol> l = accessed.toList(); l.nonEmpty(); l = l.tail) 4295 makeAccessible(l.head); 4296 for (EnumMapping map : enumSwitchMap.values()) 4297 map.translate(); 4298 checkConflicts(this.translated.toList()); 4299 checkAccessConstructorTags(); 4300 translated = this.translated; 4301 } finally { 4302 // note that recursive invocations of this method fail hard 4303 attrEnv = null; 4304 this.make = null; 4305 endPosTable = null; 4306 currentClass = null; 4307 currentMethodDef = null; 4308 outermostClassDef = null; 4309 outermostMemberDef = null; 4310 this.translated = null; 4311 classdefs = null; 4312 actualSymbols = null; 4313 freevarCache = null; 4314 proxies = null; 4315 outerThisStack = null; 4316 accessNums = null; 4317 accessSyms = null; 4318 accessConstrs = null; 4319 accessConstrTags = null; 4320 accessed = null; 4321 enumSwitchMap.clear(); 4322 assertionsDisabledClassCache = null; 4323 } 4324 return translated.toList(); 4325 } 4326 }