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