1 /*
2 * Copyright (c) 1999, 2021, Oracle and/or its affiliates. All rights reserved.
3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
4 *
5 * This code is free software; you can redistribute it and/or modify it
6 * under the terms of the GNU General Public License version 2 only, as
7 * published by the Free Software Foundation. Oracle designates this
8 * particular file as subject to the "Classpath" exception as provided
9 * by Oracle in the LICENSE file that accompanied this code.
10 *
11 * This code is distributed in the hope that it will be useful, but WITHOUT
12 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
13 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
14 * version 2 for more details (a copy is included in the LICENSE file that
15 * accompanied this code).
16 *
17 * You should have received a copy of the GNU General Public License version
18 * 2 along with this work; if not, write to the Free Software Foundation,
19 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
20 *
21 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
22 * or visit www.oracle.com if you need additional information or have any
23 * questions.
24 */
25
26 package com.sun.tools.javac.comp;
27
28 import java.util.*;
29 import java.util.stream.Collectors;
30
31 import com.sun.tools.javac.code.*;
32 import com.sun.tools.javac.code.Kinds.KindSelector;
33 import com.sun.tools.javac.code.Scope.WriteableScope;
34 import com.sun.tools.javac.jvm.*;
35 import com.sun.tools.javac.jvm.PoolConstant.LoadableConstant;
36 import com.sun.tools.javac.main.Option.PkgInfo;
37 import com.sun.tools.javac.resources.CompilerProperties.Fragments;
38 import com.sun.tools.javac.tree.*;
39 import com.sun.tools.javac.util.*;
40 import com.sun.tools.javac.util.JCDiagnostic.DiagnosticPosition;
41 import com.sun.tools.javac.util.List;
42
43 import com.sun.tools.javac.code.Symbol.*;
44 import com.sun.tools.javac.code.Symbol.OperatorSymbol.AccessCode;
45 import com.sun.tools.javac.resources.CompilerProperties.Errors;
46 import com.sun.tools.javac.tree.JCTree.*;
47 import com.sun.tools.javac.code.Type.*;
48
49 import com.sun.tools.javac.jvm.Target;
50 import com.sun.tools.javac.tree.EndPosTable;
51
52 import static com.sun.tools.javac.code.Flags.*;
53 import static com.sun.tools.javac.code.Flags.BLOCK;
54 import static com.sun.tools.javac.code.Scope.LookupKind.NON_RECURSIVE;
55 import static com.sun.tools.javac.code.TypeTag.*;
56 import static com.sun.tools.javac.code.Kinds.Kind.*;
57 import static com.sun.tools.javac.jvm.ByteCodes.*;
58 import com.sun.tools.javac.tree.JCTree.JCBreak;
59 import com.sun.tools.javac.tree.JCTree.JCCase;
60 import com.sun.tools.javac.tree.JCTree.JCExpression;
61 import com.sun.tools.javac.tree.JCTree.JCExpressionStatement;
62 import static com.sun.tools.javac.tree.JCTree.JCOperatorExpression.OperandPos.LEFT;
63 import com.sun.tools.javac.tree.JCTree.JCSwitchExpression;
64 import static com.sun.tools.javac.tree.JCTree.Tag.*;
65
66 /** This pass translates away some syntactic sugar: inner classes,
67 * class literals, assertions, foreach loops, etc.
68 *
69 * <p><b>This is NOT part of any supported API.
70 * If you write code that depends on this, you do so at your own risk.
71 * This code and its internal interfaces are subject to change or
72 * deletion without notice.</b>
73 */
74 public class Lower extends TreeTranslator {
75 protected static final Context.Key<Lower> lowerKey = new Context.Key<>();
76
77 public static Lower instance(Context context) {
78 Lower instance = context.get(lowerKey);
79 if (instance == null)
80 instance = new Lower(context);
81 return instance;
82 }
83
84 private final Names names;
85 private final Log log;
86 private final Symtab syms;
87 private final Resolve rs;
88 private final Operators operators;
89 private final Check chk;
90 private final Attr attr;
91 private TreeMaker make;
92 private DiagnosticPosition make_pos;
93 private final ConstFold cfolder;
94 private final Target target;
95 private final TypeEnvs typeEnvs;
96 private final Name dollarAssertionsDisabled;
97 private final Types types;
98 private final boolean debugLower;
99 private final boolean disableProtectedAccessors; // experimental
100 private final PkgInfo pkginfoOpt;
101
102 protected Lower(Context context) {
103 context.put(lowerKey, this);
104 names = Names.instance(context);
105 log = Log.instance(context);
106 syms = Symtab.instance(context);
107 rs = Resolve.instance(context);
108 operators = Operators.instance(context);
109 chk = Check.instance(context);
110 attr = Attr.instance(context);
111 make = TreeMaker.instance(context);
112 cfolder = ConstFold.instance(context);
113 target = Target.instance(context);
114 typeEnvs = TypeEnvs.instance(context);
115 dollarAssertionsDisabled = names.
116 fromString(target.syntheticNameChar() + "assertionsDisabled");
117
118 types = Types.instance(context);
119 Options options = Options.instance(context);
120 debugLower = options.isSet("debuglower");
121 pkginfoOpt = PkgInfo.get(options);
122 disableProtectedAccessors = options.isSet("disableProtectedAccessors");
123 }
124
125 /** The currently enclosing class.
126 */
127 ClassSymbol currentClass;
128
129 /** A queue of all translated classes.
130 */
131 ListBuffer<JCTree> translated;
132
133 /** Environment for symbol lookup, set by translateTopLevelClass.
134 */
135 Env<AttrContext> attrEnv;
136
137 /** A hash table mapping syntax trees to their ending source positions.
138 */
139 EndPosTable endPosTable;
140
141 /**************************************************************************
142 * Global mappings
143 *************************************************************************/
144
145 /** A hash table mapping local classes to their definitions.
146 */
147 Map<ClassSymbol, JCClassDecl> classdefs;
148
149 /** A hash table mapping local classes to a list of pruned trees.
150 */
151 public Map<ClassSymbol, List<JCTree>> prunedTree = new WeakHashMap<>();
152
153 /** A hash table mapping virtual accessed symbols in outer subclasses
154 * to the actually referred symbol in superclasses.
155 */
156 Map<Symbol,Symbol> actualSymbols;
157
158 /** The current method definition.
159 */
160 JCMethodDecl currentMethodDef;
161
162 /** The current method symbol.
163 */
164 MethodSymbol currentMethodSym;
165
166 /** The currently enclosing outermost class definition.
167 */
168 JCClassDecl outermostClassDef;
169
170 /** The currently enclosing outermost member definition.
171 */
172 JCTree outermostMemberDef;
173
174 /** A map from local variable symbols to their translation (as per LambdaToMethod).
175 * This is required when a capturing local class is created from a lambda (in which
176 * case the captured symbols should be replaced with the translated lambda symbols).
177 */
178 Map<Symbol, Symbol> lambdaTranslationMap = null;
179
180 /** A navigator class for assembling a mapping from local class symbols
181 * to class definition trees.
182 * There is only one case; all other cases simply traverse down the tree.
183 */
184 class ClassMap extends TreeScanner {
185
186 /** All encountered class defs are entered into classdefs table.
187 */
188 public void visitClassDef(JCClassDecl tree) {
189 classdefs.put(tree.sym, tree);
190 super.visitClassDef(tree);
191 }
192 }
193 ClassMap classMap = new ClassMap();
194
195 /** Map a class symbol to its definition.
196 * @param c The class symbol of which we want to determine the definition.
197 */
198 JCClassDecl classDef(ClassSymbol c) {
199 // First lookup the class in the classdefs table.
200 JCClassDecl def = classdefs.get(c);
201 if (def == null && outermostMemberDef != null) {
202 // If this fails, traverse outermost member definition, entering all
203 // local classes into classdefs, and try again.
204 classMap.scan(outermostMemberDef);
205 def = classdefs.get(c);
206 }
207 if (def == null) {
208 // If this fails, traverse outermost class definition, entering all
209 // local classes into classdefs, and try again.
210 classMap.scan(outermostClassDef);
211 def = classdefs.get(c);
212 }
213 return def;
214 }
215
216 /** A hash table mapping class symbols to lists of free variables.
217 * accessed by them. Only free variables of the method immediately containing
218 * a class are associated with that class.
219 */
220 Map<ClassSymbol,List<VarSymbol>> freevarCache;
221
222 /** A navigator class for collecting the free variables accessed
223 * from a local class. There is only one case; all other cases simply
224 * traverse down the tree. This class doesn't deal with the specific
225 * of Lower - it's an abstract visitor that is meant to be reused in
226 * order to share the local variable capture logic.
227 */
228 abstract class BasicFreeVarCollector extends TreeScanner {
229
230 /** Add all free variables of class c to fvs list
231 * unless they are already there.
232 */
233 abstract void addFreeVars(ClassSymbol c);
234
235 /** If tree refers to a variable in owner of local class, add it to
236 * free variables list.
237 */
238 public void visitIdent(JCIdent tree) {
239 visitSymbol(tree.sym);
240 }
241 // where
242 abstract void visitSymbol(Symbol _sym);
243
244 /** If tree refers to a class instance creation expression
245 * add all free variables of the freshly created class.
246 */
247 public void visitNewClass(JCNewClass tree) {
248 ClassSymbol c = (ClassSymbol)tree.constructor.owner;
249 addFreeVars(c);
250 super.visitNewClass(tree);
251 }
252
253 /** If tree refers to a superclass constructor call,
254 * add all free variables of the superclass.
255 */
256 public void visitApply(JCMethodInvocation tree) {
257 if (TreeInfo.name(tree.meth) == names._super) {
258 addFreeVars((ClassSymbol) TreeInfo.symbol(tree.meth).owner);
259 }
260 super.visitApply(tree);
261 }
262
263 @Override
264 public void visitYield(JCYield tree) {
265 scan(tree.value);
266 }
267
268 }
269
270 /**
271 * Lower-specific subclass of {@code BasicFreeVarCollector}.
272 */
273 class FreeVarCollector extends BasicFreeVarCollector {
274
275 /** The owner of the local class.
276 */
277 Symbol owner;
278
279 /** The local class.
280 */
281 ClassSymbol clazz;
282
283 /** The list of owner's variables accessed from within the local class,
284 * without any duplicates.
285 */
286 List<VarSymbol> fvs;
287
288 FreeVarCollector(ClassSymbol clazz) {
289 this.clazz = clazz;
290 this.owner = clazz.owner;
291 this.fvs = List.nil();
292 }
293
294 /** Add free variable to fvs list unless it is already there.
295 */
296 private void addFreeVar(VarSymbol v) {
297 for (List<VarSymbol> l = fvs; l.nonEmpty(); l = l.tail)
298 if (l.head == v) return;
299 fvs = fvs.prepend(v);
300 }
301
302 @Override
303 void addFreeVars(ClassSymbol c) {
304 List<VarSymbol> fvs = freevarCache.get(c);
305 if (fvs != null) {
306 for (List<VarSymbol> l = fvs; l.nonEmpty(); l = l.tail) {
307 addFreeVar(l.head);
308 }
309 }
310 }
311
312 @Override
313 void visitSymbol(Symbol _sym) {
314 Symbol sym = _sym;
315 if (sym.kind == VAR || sym.kind == MTH) {
316 if (sym != null && sym.owner != owner)
317 sym = proxies.get(sym);
318 if (sym != null && sym.owner == owner) {
319 VarSymbol v = (VarSymbol)sym;
320 if (v.getConstValue() == null) {
321 addFreeVar(v);
322 }
323 } else {
324 if (outerThisStack.head != null &&
325 outerThisStack.head != _sym)
326 visitSymbol(outerThisStack.head);
327 }
328 }
329 }
330
331 /** If tree refers to a class instance creation expression
332 * add all free variables of the freshly created class.
333 */
334 public void visitNewClass(JCNewClass tree) {
335 ClassSymbol c = (ClassSymbol)tree.constructor.owner;
336 if (tree.encl == null &&
337 c.hasOuterInstance() &&
338 outerThisStack.head != null)
339 visitSymbol(outerThisStack.head);
340 super.visitNewClass(tree);
341 }
342
343 /** If tree refers to a qualified this or super expression
344 * for anything but the current class, add the outer this
345 * stack as a free variable.
346 */
347 public void visitSelect(JCFieldAccess tree) {
348 if ((tree.name == names._this || tree.name == names._super) &&
349 tree.selected.type.tsym != clazz &&
350 outerThisStack.head != null)
351 visitSymbol(outerThisStack.head);
352 super.visitSelect(tree);
353 }
354
355 /** If tree refers to a superclass constructor call,
356 * add all free variables of the superclass.
357 */
358 public void visitApply(JCMethodInvocation tree) {
359 if (TreeInfo.name(tree.meth) == names._super) {
360 Symbol constructor = TreeInfo.symbol(tree.meth);
361 ClassSymbol c = (ClassSymbol)constructor.owner;
362 if (c.hasOuterInstance() &&
363 !tree.meth.hasTag(SELECT) &&
364 outerThisStack.head != null)
365 visitSymbol(outerThisStack.head);
366 }
367 super.visitApply(tree);
368 }
369
370 }
371
372 ClassSymbol ownerToCopyFreeVarsFrom(ClassSymbol c) {
373 if (!c.isDirectlyOrIndirectlyLocal()) {
374 return null;
375 }
376 Symbol currentOwner = c.owner;
377 while (currentOwner.owner.kind.matches(KindSelector.TYP) && currentOwner.isDirectlyOrIndirectlyLocal()) {
378 currentOwner = currentOwner.owner;
379 }
380 if (currentOwner.owner.kind.matches(KindSelector.VAL_MTH) && c.isSubClass(currentOwner, types)) {
381 return (ClassSymbol)currentOwner;
382 }
383 return null;
384 }
385
386 /** Return the variables accessed from within a local class, which
387 * are declared in the local class' owner.
388 * (in reverse order of first access).
389 */
390 List<VarSymbol> freevars(ClassSymbol c) {
391 List<VarSymbol> fvs = freevarCache.get(c);
392 if (fvs != null) {
393 return fvs;
394 }
395 if (c.owner.kind.matches(KindSelector.VAL_MTH)) {
396 FreeVarCollector collector = new FreeVarCollector(c);
397 collector.scan(classDef(c));
398 fvs = collector.fvs;
399 freevarCache.put(c, fvs);
400 return fvs;
401 } else {
402 ClassSymbol owner = ownerToCopyFreeVarsFrom(c);
403 if (owner != null) {
404 fvs = freevarCache.get(owner);
405 freevarCache.put(c, fvs);
406 return fvs;
407 } else {
408 return List.nil();
409 }
410 }
411 }
412
413 Map<TypeSymbol,EnumMapping> enumSwitchMap = new LinkedHashMap<>();
414
415 EnumMapping mapForEnum(DiagnosticPosition pos, TypeSymbol enumClass) {
416 EnumMapping map = enumSwitchMap.get(enumClass);
417 if (map == null)
418 enumSwitchMap.put(enumClass, map = new EnumMapping(pos, enumClass));
419 return map;
420 }
421
422 /** This map gives a translation table to be used for enum
423 * switches.
424 *
425 * <p>For each enum that appears as the type of a switch
426 * expression, we maintain an EnumMapping to assist in the
427 * translation, as exemplified by the following example:
428 *
429 * <p>we translate
430 * <pre>
431 * switch(colorExpression) {
432 * case red: stmt1;
433 * case green: stmt2;
434 * }
435 * </pre>
436 * into
437 * <pre>
438 * switch(Outer$0.$EnumMap$Color[colorExpression.ordinal()]) {
439 * case 1: stmt1;
440 * case 2: stmt2
441 * }
442 * </pre>
443 * with the auxiliary table initialized as follows:
444 * <pre>
445 * class Outer$0 {
446 * synthetic final int[] $EnumMap$Color = new int[Color.values().length];
447 * static {
448 * try { $EnumMap$Color[red.ordinal()] = 1; } catch (NoSuchFieldError ex) {}
449 * try { $EnumMap$Color[green.ordinal()] = 2; } catch (NoSuchFieldError ex) {}
450 * }
451 * }
452 * </pre>
453 * class EnumMapping provides mapping data and support methods for this translation.
454 */
455 class EnumMapping {
456 EnumMapping(DiagnosticPosition pos, TypeSymbol forEnum) {
457 this.forEnum = forEnum;
458 this.values = new LinkedHashMap<>();
459 this.pos = pos;
460 Name varName = names
461 .fromString(target.syntheticNameChar() +
462 "SwitchMap" +
463 target.syntheticNameChar() +
464 names.fromUtf(ClassWriter.externalize(forEnum.type.tsym.flatName())).toString()
465 .replace('/', '.')
466 .replace('.', target.syntheticNameChar()));
467 ClassSymbol outerCacheClass = outerCacheClass();
468 this.mapVar = new VarSymbol(STATIC | SYNTHETIC | FINAL,
469 varName,
470 new ArrayType(syms.intType, syms.arrayClass),
471 outerCacheClass);
472 enterSynthetic(pos, mapVar, outerCacheClass.members());
473 }
474
475 DiagnosticPosition pos = null;
476
477 // the next value to use
478 int next = 1; // 0 (unused map elements) go to the default label
479
480 // the enum for which this is a map
481 final TypeSymbol forEnum;
482
483 // the field containing the map
484 final VarSymbol mapVar;
485
486 // the mapped values
487 final Map<VarSymbol,Integer> values;
488
489 JCLiteral forConstant(VarSymbol v) {
490 Integer result = values.get(v);
491 if (result == null)
492 values.put(v, result = next++);
493 return make.Literal(result);
494 }
495
496 // generate the field initializer for the map
497 void translate() {
498 make.at(pos.getStartPosition());
499 JCClassDecl owner = classDef((ClassSymbol)mapVar.owner);
500
501 // synthetic static final int[] $SwitchMap$Color = new int[Color.values().length];
502 MethodSymbol valuesMethod = lookupMethod(pos,
503 names.values,
504 forEnum.type,
505 List.nil());
506 JCExpression size = make // Color.values().length
507 .Select(make.App(make.QualIdent(valuesMethod)),
508 syms.lengthVar);
509 JCExpression mapVarInit = make
510 .NewArray(make.Type(syms.intType), List.of(size), null)
511 .setType(new ArrayType(syms.intType, syms.arrayClass));
512
513 // try { $SwitchMap$Color[red.ordinal()] = 1; } catch (java.lang.NoSuchFieldError ex) {}
514 ListBuffer<JCStatement> stmts = new ListBuffer<>();
515 Symbol ordinalMethod = lookupMethod(pos,
516 names.ordinal,
517 forEnum.type,
518 List.nil());
519 List<JCCatch> catcher = List.<JCCatch>nil()
520 .prepend(make.Catch(make.VarDef(new VarSymbol(PARAMETER, names.ex,
521 syms.noSuchFieldErrorType,
522 syms.noSymbol),
523 null),
524 make.Block(0, List.nil())));
525 for (Map.Entry<VarSymbol,Integer> e : values.entrySet()) {
526 VarSymbol enumerator = e.getKey();
527 Integer mappedValue = e.getValue();
528 JCExpression assign = make
529 .Assign(make.Indexed(mapVar,
530 make.App(make.Select(make.QualIdent(enumerator),
531 ordinalMethod))),
532 make.Literal(mappedValue))
533 .setType(syms.intType);
534 JCStatement exec = make.Exec(assign);
535 JCStatement _try = make.Try(make.Block(0, List.of(exec)), catcher, null);
536 stmts.append(_try);
537 }
538
539 owner.defs = owner.defs
540 .prepend(make.Block(STATIC, stmts.toList()))
541 .prepend(make.VarDef(mapVar, mapVarInit));
542 }
543 }
544
545
546 /**************************************************************************
547 * Tree building blocks
548 *************************************************************************/
549
550 /** Equivalent to make.at(pos.getStartPosition()) with side effect of caching
551 * pos as make_pos, for use in diagnostics.
552 **/
553 TreeMaker make_at(DiagnosticPosition pos) {
554 make_pos = pos;
555 return make.at(pos);
556 }
557
558 /** Make an attributed tree representing a literal. This will be an
559 * Ident node in the case of boolean literals, a Literal node in all
560 * other cases.
561 * @param type The literal's type.
562 * @param value The literal's value.
563 */
564 JCExpression makeLit(Type type, Object value) {
565 return make.Literal(type.getTag(), value).setType(type.constType(value));
566 }
567
568 /** Make an attributed tree representing null.
569 */
570 JCExpression makeNull() {
571 return makeLit(syms.botType, null);
572 }
573
574 /** Make an attributed class instance creation expression.
575 * @param ctype The class type.
576 * @param args The constructor arguments.
577 */
578 JCNewClass makeNewClass(Type ctype, List<JCExpression> args) {
579 JCNewClass tree = make.NewClass(null,
580 null, make.QualIdent(ctype.tsym), args, null);
581 tree.constructor = rs.resolveConstructor(
582 make_pos, attrEnv, ctype, TreeInfo.types(args), List.nil());
583 tree.type = ctype;
584 return tree;
585 }
586
587 /** Make an attributed unary expression.
588 * @param optag The operators tree tag.
589 * @param arg The operator's argument.
590 */
591 JCUnary makeUnary(JCTree.Tag optag, JCExpression arg) {
592 JCUnary tree = make.Unary(optag, arg);
593 tree.operator = operators.resolveUnary(tree, optag, arg.type);
594 tree.type = tree.operator.type.getReturnType();
595 return tree;
596 }
597
598 /** Make an attributed binary expression.
599 * @param optag The operators tree tag.
600 * @param lhs The operator's left argument.
601 * @param rhs The operator's right argument.
602 */
603 JCBinary makeBinary(JCTree.Tag optag, JCExpression lhs, JCExpression rhs) {
604 JCBinary tree = make.Binary(optag, lhs, rhs);
605 tree.operator = operators.resolveBinary(tree, optag, lhs.type, rhs.type);
606 tree.type = tree.operator.type.getReturnType();
607 return tree;
608 }
609
610 /** Make an attributed assignop expression.
611 * @param optag The operators tree tag.
612 * @param lhs The operator's left argument.
613 * @param rhs The operator's right argument.
614 */
615 JCAssignOp makeAssignop(JCTree.Tag optag, JCTree lhs, JCTree rhs) {
616 JCAssignOp tree = make.Assignop(optag, lhs, rhs);
617 tree.operator = operators.resolveBinary(tree, tree.getTag().noAssignOp(), lhs.type, rhs.type);
618 tree.type = lhs.type;
619 return tree;
620 }
621
622 /** Convert tree into string object, unless it has already a
623 * reference type..
624 */
625 JCExpression makeString(JCExpression tree) {
626 if (!tree.type.isPrimitiveOrVoid()) {
627 return tree;
628 } else {
629 Symbol valueOfSym = lookupMethod(tree.pos(),
630 names.valueOf,
631 syms.stringType,
632 List.of(tree.type));
633 return make.App(make.QualIdent(valueOfSym), List.of(tree));
634 }
635 }
636
637 /** Create an empty anonymous class definition and enter and complete
638 * its symbol. Return the class definition's symbol.
639 * and create
640 * @param flags The class symbol's flags
641 * @param owner The class symbol's owner
642 */
643 JCClassDecl makeEmptyClass(long flags, ClassSymbol owner) {
644 return makeEmptyClass(flags, owner, null, true);
645 }
646
647 JCClassDecl makeEmptyClass(long flags, ClassSymbol owner, Name flatname,
648 boolean addToDefs) {
649 // Create class symbol.
650 ClassSymbol c = syms.defineClass(names.empty, owner);
651 if (flatname != null) {
652 c.flatname = flatname;
653 } else {
654 c.flatname = chk.localClassName(c);
655 }
656 c.sourcefile = owner.sourcefile;
657 c.completer = Completer.NULL_COMPLETER;
658 c.members_field = WriteableScope.create(c);
659 c.flags_field = flags;
660 ClassType ctype = (ClassType) c.type;
661 ctype.supertype_field = syms.objectType;
662 ctype.interfaces_field = List.nil();
663
664 JCClassDecl odef = classDef(owner);
665
666 // Enter class symbol in owner scope and compiled table.
667 enterSynthetic(odef.pos(), c, owner.members());
668 chk.putCompiled(c);
669
670 // Create class definition tree.
671 JCClassDecl cdef = make.ClassDef(
672 make.Modifiers(flags), names.empty,
673 List.nil(),
674 null, List.nil(), List.nil());
675 cdef.sym = c;
676 cdef.type = c.type;
677
678 // Append class definition tree to owner's definitions.
679 if (addToDefs) odef.defs = odef.defs.prepend(cdef);
680 return cdef;
681 }
682
683 /**************************************************************************
684 * Symbol manipulation utilities
685 *************************************************************************/
686
687 /** Enter a synthetic symbol in a given scope, but complain if there was already one there.
688 * @param pos Position for error reporting.
689 * @param sym The symbol.
690 * @param s The scope.
691 */
692 private void enterSynthetic(DiagnosticPosition pos, Symbol sym, WriteableScope s) {
693 s.enter(sym);
694 }
695
696 /** Create a fresh synthetic name within a given scope - the unique name is
697 * obtained by appending '$' chars at the end of the name until no match
698 * is found.
699 *
700 * @param name base name
701 * @param s scope in which the name has to be unique
702 * @return fresh synthetic name
703 */
704 private Name makeSyntheticName(Name name, Scope s) {
705 do {
706 name = name.append(
707 target.syntheticNameChar(),
708 names.empty);
709 } while (lookupSynthetic(name, s) != null);
710 return name;
711 }
712
713 /** Check whether synthetic symbols generated during lowering conflict
714 * with user-defined symbols.
715 *
716 * @param translatedTrees lowered class trees
717 */
718 void checkConflicts(List<JCTree> translatedTrees) {
719 for (JCTree t : translatedTrees) {
720 t.accept(conflictsChecker);
721 }
722 }
723
724 JCTree.Visitor conflictsChecker = new TreeScanner() {
725
726 TypeSymbol currentClass;
727
728 @Override
729 public void visitMethodDef(JCMethodDecl that) {
730 checkConflicts(that.pos(), that.sym, currentClass);
731 super.visitMethodDef(that);
732 }
733
734 @Override
735 public void visitVarDef(JCVariableDecl that) {
736 if (that.sym.owner.kind == TYP) {
737 checkConflicts(that.pos(), that.sym, currentClass);
738 }
739 super.visitVarDef(that);
740 }
741
742 @Override
743 public void visitClassDef(JCClassDecl that) {
744 TypeSymbol prevCurrentClass = currentClass;
745 currentClass = that.sym;
746 try {
747 super.visitClassDef(that);
748 }
749 finally {
750 currentClass = prevCurrentClass;
751 }
752 }
753
754 void checkConflicts(DiagnosticPosition pos, Symbol sym, TypeSymbol c) {
755 for (Type ct = c.type; ct != Type.noType ; ct = types.supertype(ct)) {
756 for (Symbol sym2 : ct.tsym.members().getSymbolsByName(sym.name, NON_RECURSIVE)) {
757 // VM allows methods and variables with differing types
758 if (sym.kind == sym2.kind &&
759 types.isSameType(types.erasure(sym.type), types.erasure(sym2.type)) &&
760 sym != sym2 &&
761 (sym.flags() & Flags.SYNTHETIC) != (sym2.flags() & Flags.SYNTHETIC) &&
762 (sym.flags() & BRIDGE) == 0 && (sym2.flags() & BRIDGE) == 0) {
763 syntheticError(pos, (sym2.flags() & SYNTHETIC) == 0 ? sym2 : sym);
764 return;
765 }
766 }
767 }
768 }
769
770 /** Report a conflict between a user symbol and a synthetic symbol.
771 */
772 private void syntheticError(DiagnosticPosition pos, Symbol sym) {
773 if (!sym.type.isErroneous()) {
774 log.error(pos, Errors.CannotGenerateClass(sym.location(), Fragments.SyntheticNameConflict(sym, sym.location())));
775 }
776 }
777 };
778
779 /** Look up a synthetic name in a given scope.
780 * @param s The scope.
781 * @param name The name.
782 */
783 private Symbol lookupSynthetic(Name name, Scope s) {
784 Symbol sym = s.findFirst(name);
785 return (sym==null || (sym.flags()&SYNTHETIC)==0) ? null : sym;
786 }
787
788 /** Look up a method in a given scope.
789 */
790 private MethodSymbol lookupMethod(DiagnosticPosition pos, Name name, Type qual, List<Type> args) {
791 return rs.resolveInternalMethod(pos, attrEnv, qual, name, args, List.nil());
792 }
793
794 /** Anon inner classes are used as access constructor tags.
795 * accessConstructorTag will use an existing anon class if one is available,
796 * and synthesize a class (with makeEmptyClass) if one is not available.
797 * However, there is a small possibility that an existing class will not
798 * be generated as expected if it is inside a conditional with a constant
799 * expression. If that is found to be the case, create an empty class tree here.
800 */
801 private void checkAccessConstructorTags() {
802 for (List<ClassSymbol> l = accessConstrTags; l.nonEmpty(); l = l.tail) {
803 ClassSymbol c = l.head;
804 if (isTranslatedClassAvailable(c))
805 continue;
806 // Create class definition tree.
807 JCClassDecl cdec = makeEmptyClass(STATIC | SYNTHETIC,
808 c.outermostClass(), c.flatname, false);
809 swapAccessConstructorTag(c, cdec.sym);
810 translated.append(cdec);
811 }
812 }
813 // where
814 private boolean isTranslatedClassAvailable(ClassSymbol c) {
815 for (JCTree tree: translated) {
816 if (tree.hasTag(CLASSDEF)
817 && ((JCClassDecl) tree).sym == c) {
818 return true;
819 }
820 }
821 return false;
822 }
823
824 void swapAccessConstructorTag(ClassSymbol oldCTag, ClassSymbol newCTag) {
825 for (MethodSymbol methodSymbol : accessConstrs.values()) {
826 Assert.check(methodSymbol.type.hasTag(METHOD));
827 MethodType oldMethodType =
828 (MethodType)methodSymbol.type;
829 if (oldMethodType.argtypes.head.tsym == oldCTag)
830 methodSymbol.type =
831 types.createMethodTypeWithParameters(oldMethodType,
832 oldMethodType.getParameterTypes().tail
833 .prepend(newCTag.erasure(types)));
834 }
835 }
836
837 /**************************************************************************
838 * Access methods
839 *************************************************************************/
840
841 /** A mapping from symbols to their access numbers.
842 */
843 private Map<Symbol,Integer> accessNums;
844
845 /** A mapping from symbols to an array of access symbols, indexed by
846 * access code.
847 */
848 private Map<Symbol,MethodSymbol[]> accessSyms;
849
850 /** A mapping from (constructor) symbols to access constructor symbols.
851 */
852 private Map<Symbol,MethodSymbol> accessConstrs;
853
854 /** A list of all class symbols used for access constructor tags.
855 */
856 private List<ClassSymbol> accessConstrTags;
857
858 /** A queue for all accessed symbols.
859 */
860 private ListBuffer<Symbol> accessed;
861
862 /** return access code for identifier,
863 * @param tree The tree representing the identifier use.
864 * @param enclOp The closest enclosing operation node of tree,
865 * null if tree is not a subtree of an operation.
866 */
867 private static int accessCode(JCTree tree, JCTree enclOp) {
868 if (enclOp == null)
869 return AccessCode.DEREF.code;
870 else if (enclOp.hasTag(ASSIGN) &&
871 tree == TreeInfo.skipParens(((JCAssign) enclOp).lhs))
872 return AccessCode.ASSIGN.code;
873 else if (enclOp.hasTag(WITHFIELD) &&
874 tree == TreeInfo.skipParens(((JCWithField) enclOp).field))
875 return AccessCode.WITHFIELD.code;
876 else if ((enclOp.getTag().isIncOrDecUnaryOp() || enclOp.getTag().isAssignop()) &&
877 tree == TreeInfo.skipParens(((JCOperatorExpression) enclOp).getOperand(LEFT)))
878 return (((JCOperatorExpression) enclOp).operator).getAccessCode(enclOp.getTag());
879 else
880 return AccessCode.DEREF.code;
881 }
882
883 /** Return binary operator that corresponds to given access code.
884 */
885 private OperatorSymbol binaryAccessOperator(int acode, Tag tag) {
886 return operators.lookupBinaryOp(op -> op.getAccessCode(tag) == acode);
887 }
888
889 /** Return tree tag for assignment operation corresponding
890 * to given binary operator.
891 */
892 private static JCTree.Tag treeTag(OperatorSymbol operator) {
893 switch (operator.opcode) {
894 case ByteCodes.ior: case ByteCodes.lor:
895 return BITOR_ASG;
896 case ByteCodes.ixor: case ByteCodes.lxor:
897 return BITXOR_ASG;
898 case ByteCodes.iand: case ByteCodes.land:
899 return BITAND_ASG;
900 case ByteCodes.ishl: case ByteCodes.lshl:
901 case ByteCodes.ishll: case ByteCodes.lshll:
902 return SL_ASG;
903 case ByteCodes.ishr: case ByteCodes.lshr:
904 case ByteCodes.ishrl: case ByteCodes.lshrl:
905 return SR_ASG;
906 case ByteCodes.iushr: case ByteCodes.lushr:
907 case ByteCodes.iushrl: case ByteCodes.lushrl:
908 return USR_ASG;
909 case ByteCodes.iadd: case ByteCodes.ladd:
910 case ByteCodes.fadd: case ByteCodes.dadd:
911 case ByteCodes.string_add:
912 return PLUS_ASG;
913 case ByteCodes.isub: case ByteCodes.lsub:
914 case ByteCodes.fsub: case ByteCodes.dsub:
915 return MINUS_ASG;
916 case ByteCodes.imul: case ByteCodes.lmul:
917 case ByteCodes.fmul: case ByteCodes.dmul:
918 return MUL_ASG;
919 case ByteCodes.idiv: case ByteCodes.ldiv:
920 case ByteCodes.fdiv: case ByteCodes.ddiv:
921 return DIV_ASG;
922 case ByteCodes.imod: case ByteCodes.lmod:
923 case ByteCodes.fmod: case ByteCodes.dmod:
924 return MOD_ASG;
925 default:
926 throw new AssertionError();
927 }
928 }
929
930 /** The name of the access method with number `anum' and access code `acode'.
931 */
932 Name accessName(int anum, int acode) {
933 return names.fromString(
934 "access" + target.syntheticNameChar() + anum + acode / 10 + acode % 10);
935 }
936
937 /** Return access symbol for a private or protected symbol from an inner class.
938 * @param sym The accessed private symbol.
939 * @param tree The accessing tree.
940 * @param enclOp The closest enclosing operation node of tree,
941 * null if tree is not a subtree of an operation.
942 * @param protAccess Is access to a protected symbol in another
943 * package?
944 * @param refSuper Is access via a (qualified) C.super?
945 */
946 MethodSymbol accessSymbol(Symbol sym, JCTree tree, JCTree enclOp,
947 boolean protAccess, boolean refSuper) {
948 ClassSymbol accOwner = refSuper && protAccess
949 // For access via qualified super (T.super.x), place the
950 // access symbol on T.
951 ? (ClassSymbol)((JCFieldAccess) tree).selected.type.tsym
952 // Otherwise pretend that the owner of an accessed
953 // protected symbol is the enclosing class of the current
954 // class which is a subclass of the symbol's owner.
955 : accessClass(sym, protAccess, tree);
956
957 Symbol vsym = sym;
958 if (sym.owner != accOwner) {
959 vsym = sym.clone(accOwner);
960 actualSymbols.put(vsym, sym);
961 }
962
963 Integer anum // The access number of the access method.
964 = accessNums.get(vsym);
965 if (anum == null) {
966 anum = accessed.length();
967 accessNums.put(vsym, anum);
968 accessSyms.put(vsym, new MethodSymbol[AccessCode.numberOfAccessCodes]);
969 accessed.append(vsym);
970 // System.out.println("accessing " + vsym + " in " + vsym.location());
971 }
972
973 int acode; // The access code of the access method.
974 List<Type> argtypes; // The argument types of the access method.
975 Type restype; // The result type of the access method.
976 List<Type> thrown; // The thrown exceptions of the access method.
977 switch (vsym.kind) {
978 case VAR:
979 acode = accessCode(tree, enclOp);
980 if (acode >= AccessCode.FIRSTASGOP.code) {
981 OperatorSymbol operator = binaryAccessOperator(acode, enclOp.getTag());
982 if (operator.opcode == string_add)
983 argtypes = List.of(syms.objectType);
984 else
985 argtypes = operator.type.getParameterTypes().tail;
986 } else if (acode == AccessCode.ASSIGN.code || acode == AccessCode.WITHFIELD.code)
987 argtypes = List.of(vsym.erasure(types));
988 else
989 argtypes = List.nil();
990 restype = acode == AccessCode.WITHFIELD.code ? vsym.owner.erasure(types) : vsym.erasure(types);
991 thrown = List.nil();
992 break;
993 case MTH:
994 acode = AccessCode.DEREF.code;
995 argtypes = vsym.erasure(types).getParameterTypes();
996 restype = vsym.erasure(types).getReturnType();
997 thrown = vsym.type.getThrownTypes();
998 break;
999 default:
1000 throw new AssertionError();
1001 }
1002
1003 // For references via qualified super, increment acode by one,
1004 // making it odd.
1005 if (protAccess && refSuper) acode++;
1006
1007 // Instance access methods get instance as first parameter.
1008 // For protected symbols this needs to be the instance as a member
1009 // of the type containing the accessed symbol, not the class
1010 // containing the access method.
1011 if ((vsym.flags() & STATIC) == 0) {
1012 argtypes = argtypes.prepend(vsym.owner.erasure(types));
1013 }
1014 MethodSymbol[] accessors = accessSyms.get(vsym);
1015 MethodSymbol accessor = accessors[acode];
1016 if (accessor == null) {
1017 accessor = new MethodSymbol(
1018 STATIC | SYNTHETIC | (accOwner.isInterface() ? PUBLIC : 0),
1019 accessName(anum.intValue(), acode),
1020 new MethodType(argtypes, restype, thrown, syms.methodClass),
1021 accOwner);
1022 enterSynthetic(tree.pos(), accessor, accOwner.members());
1023 accessors[acode] = accessor;
1024 }
1025 return accessor;
1026 }
1027
1028 /** The qualifier to be used for accessing a symbol in an outer class.
1029 * This is either C.sym or C.this.sym, depending on whether or not
1030 * sym is static.
1031 * @param sym The accessed symbol.
1032 */
1033 JCExpression accessBase(DiagnosticPosition pos, Symbol sym) {
1034 return (sym.flags() & STATIC) != 0
1035 ? access(make.at(pos.getStartPosition()).QualIdent(sym.owner))
1036 : makeOwnerThis(pos, sym, true);
1037 }
1038
1039 /** Do we need an access method to reference private symbol?
1040 */
1041 boolean needsPrivateAccess(Symbol sym) {
1042 if (target.hasNestmateAccess()) {
1043 return false;
1044 }
1045 if ((sym.flags() & PRIVATE) == 0 || sym.owner == currentClass) {
1046 return false;
1047 } else if (sym.name == names.init && sym.owner.isDirectlyOrIndirectlyLocal()) {
1048 // private constructor in local class: relax protection
1049 sym.flags_field &= ~PRIVATE;
1050 return false;
1051 } else {
1052 return true;
1053 }
1054 }
1055
1056 /** Do we need an access method to reference symbol in other package?
1057 */
1058 boolean needsProtectedAccess(Symbol sym, JCTree tree) {
1059 if (disableProtectedAccessors) return false;
1060 if ((sym.flags() & PROTECTED) == 0 ||
1061 sym.owner.owner == currentClass.owner || // fast special case
1062 sym.packge() == currentClass.packge())
1063 return false;
1064 if (!currentClass.isSubClass(sym.owner, types))
1065 return true;
1066 if ((sym.flags() & STATIC) != 0 ||
1067 !tree.hasTag(SELECT) ||
1068 TreeInfo.name(((JCFieldAccess) tree).selected) == names._super)
1069 return false;
1070 return !((JCFieldAccess) tree).selected.type.tsym.isSubClass(currentClass, types);
1071 }
1072
1073 /** The class in which an access method for given symbol goes.
1074 * @param sym The access symbol
1075 * @param protAccess Is access to a protected symbol in another
1076 * package?
1077 */
1078 ClassSymbol accessClass(Symbol sym, boolean protAccess, JCTree tree) {
1079 if (protAccess) {
1080 Symbol qualifier = null;
1081 ClassSymbol c = currentClass;
1082 if (tree.hasTag(SELECT) && (sym.flags() & STATIC) == 0) {
1083 qualifier = ((JCFieldAccess) tree).selected.type.tsym;
1084 while (!qualifier.isSubClass(c, types)) {
1085 c = c.owner.enclClass();
1086 }
1087 return c;
1088 } else {
1089 while (!c.isSubClass(sym.owner, types)) {
1090 c = c.owner.enclClass();
1091 }
1092 }
1093 return c;
1094 } else {
1095 // the symbol is private
1096 return sym.owner.enclClass();
1097 }
1098 }
1099
1100 private void addPrunedInfo(JCTree tree) {
1101 List<JCTree> infoList = prunedTree.get(currentClass);
1102 infoList = (infoList == null) ? List.of(tree) : infoList.prepend(tree);
1103 prunedTree.put(currentClass, infoList);
1104 }
1105
1106 /** Ensure that identifier is accessible, return tree accessing the identifier.
1107 * @param sym The accessed symbol.
1108 * @param tree The tree referring to the symbol.
1109 * @param enclOp The closest enclosing operation node of tree,
1110 * null if tree is not a subtree of an operation.
1111 * @param refSuper Is access via a (qualified) C.super?
1112 */
1113 JCExpression access(Symbol sym, JCExpression tree, JCExpression enclOp, boolean refSuper) {
1114 // Access a free variable via its proxy, or its proxy's proxy
1115 while (sym.kind == VAR && sym.owner.kind == MTH &&
1116 sym.owner.enclClass() != currentClass) {
1117 // A constant is replaced by its constant value.
1118 Object cv = ((VarSymbol)sym).getConstValue();
1119 if (cv != null) {
1120 make.at(tree.pos);
1121 return makeLit(sym.type, cv);
1122 }
1123 if (lambdaTranslationMap != null && lambdaTranslationMap.get(sym) != null) {
1124 return make.at(tree.pos).Ident(lambdaTranslationMap.get(sym));
1125 } else {
1126 // Otherwise replace the variable by its proxy.
1127 sym = proxies.get(sym);
1128 Assert.check(sym != null && (sym.flags_field & FINAL) != 0);
1129 tree = make.at(tree.pos).Ident(sym);
1130 }
1131 }
1132 JCExpression base = (tree.hasTag(SELECT)) ? ((JCFieldAccess) tree).selected : null;
1133 switch (sym.kind) {
1134 case TYP:
1135 if (sym.owner.kind != PCK) {
1136 // Make sure not to lose type fidelity due to symbol sharing between projections
1137 boolean requireReferenceProjection =
1138 tree.hasTag(SELECT) && ((JCFieldAccess) tree).name == names.ref && tree.type.isReferenceProjection();
1139 boolean requireValueProjection =
1140 tree.hasTag(SELECT) && ((JCFieldAccess) tree).name == names.val && tree.type.isValueProjection();
1141 // Convert type idents to
1142 // <flat name> or <package name> . <flat name>
1143 Name flatname = Convert.shortName(sym.flatName());
1144 while (base != null &&
1145 TreeInfo.symbol(base) != null &&
1146 TreeInfo.symbol(base).kind != PCK) {
1147 base = (base.hasTag(SELECT))
1148 ? ((JCFieldAccess) base).selected
1149 : null;
1150 }
1151 if (tree.hasTag(IDENT)) {
1152 ((JCIdent) tree).name = flatname;
1153 } else if (base == null) {
1154 tree = make.at(tree.pos).Ident(sym);
1155 ((JCIdent) tree).name = flatname;
1156 if (requireReferenceProjection) {
1157 tree.setType(tree.type.referenceProjection());
1158 } else if (requireValueProjection) {
1159 tree.setType(tree.type.asValueType());
1160 }
1161 } else {
1162 ((JCFieldAccess) tree).selected = base;
1163 ((JCFieldAccess) tree).name = flatname;
1164 if (requireReferenceProjection) {
1165 tree.setType(tree.type.referenceProjection());
1166 } else if (requireValueProjection) {
1167 tree.setType(tree.type.asValueType());
1168 }
1169 }
1170 }
1171 break;
1172 case MTH: case VAR:
1173 if (sym.owner.kind == TYP) {
1174
1175 // Access methods are required for
1176 // - private members,
1177 // - protected members in a superclass of an
1178 // enclosing class contained in another package.
1179 // - all non-private members accessed via a qualified super.
1180 boolean protAccess = refSuper && !needsPrivateAccess(sym)
1181 || needsProtectedAccess(sym, tree);
1182 boolean accReq = protAccess || needsPrivateAccess(sym);
1183
1184 // A base has to be supplied for
1185 // - simple identifiers accessing variables in outer classes.
1186 boolean baseReq =
1187 base == null &&
1188 sym.owner != syms.predefClass &&
1189 !sym.isMemberOf(currentClass, types);
1190
1191 if (accReq || baseReq) {
1192 make.at(tree.pos);
1193
1194 // Constants are replaced by their constant value.
1195 if (sym.kind == VAR) {
1196 Object cv = ((VarSymbol)sym).getConstValue();
1197 if (cv != null) {
1198 addPrunedInfo(tree);
1199 return makeLit(sym.type, cv);
1200 }
1201 }
1202
1203 // Private variables and methods are replaced by calls
1204 // to their access methods.
1205 if (accReq) {
1206 List<JCExpression> args = List.nil();
1207 if ((sym.flags() & STATIC) == 0) {
1208 // Instance access methods get instance
1209 // as first parameter.
1210 if (base == null)
1211 base = makeOwnerThis(tree.pos(), sym, true);
1212 args = args.prepend(base);
1213 base = null; // so we don't duplicate code
1214 }
1215 Symbol access = accessSymbol(sym, tree,
1216 enclOp, protAccess,
1217 refSuper);
1218 JCExpression receiver = make.Select(
1219 base != null ? base : make.QualIdent(access.owner),
1220 access);
1221 return make.App(receiver, args);
1222
1223 // Other accesses to members of outer classes get a
1224 // qualifier.
1225 } else if (baseReq) {
1226 return make.at(tree.pos).Select(
1227 accessBase(tree.pos(), sym), sym).setType(tree.type);
1228 }
1229 }
1230 } else if (sym.owner.kind == MTH && lambdaTranslationMap != null) {
1231 //sym is a local variable - check the lambda translation map to
1232 //see if sym has been translated to something else in the current
1233 //scope (by LambdaToMethod)
1234 Symbol translatedSym = lambdaTranslationMap.get(sym.baseSymbol());
1235 if (translatedSym != null) {
1236 tree = make.at(tree.pos).Ident(translatedSym);
1237 }
1238 }
1239 }
1240 return tree;
1241 }
1242
1243 /** Ensure that identifier is accessible, return tree accessing the identifier.
1244 * @param tree The identifier tree.
1245 */
1246 JCExpression access(JCExpression tree) {
1247 Symbol sym = TreeInfo.symbol(tree);
1248 return sym == null ? tree : access(sym, tree, null, false);
1249 }
1250
1251 /** Return access constructor for a private constructor,
1252 * or the constructor itself, if no access constructor is needed.
1253 * @param pos The position to report diagnostics, if any.
1254 * @param constr The private constructor.
1255 */
1256 Symbol accessConstructor(DiagnosticPosition pos, Symbol constr) {
1257 if (needsPrivateAccess(constr)) {
1258 ClassSymbol accOwner = constr.owner.enclClass();
1259 MethodSymbol aconstr = accessConstrs.get(constr);
1260 if (aconstr == null) {
1261 List<Type> argtypes = constr.type.getParameterTypes();
1262 if ((accOwner.flags_field & ENUM) != 0)
1263 argtypes = argtypes
1264 .prepend(syms.intType)
1265 .prepend(syms.stringType);
1266 aconstr = new MethodSymbol(
1267 SYNTHETIC,
1268 names.init,
1269 new MethodType(
1270 argtypes.append(
1271 accessConstructorTag().erasure(types)),
1272 constr.type.getReturnType(),
1273 constr.type.getThrownTypes(),
1274 syms.methodClass),
1275 accOwner);
1276 enterSynthetic(pos, aconstr, accOwner.members());
1277 accessConstrs.put(constr, aconstr);
1278 accessed.append(constr);
1279 }
1280 return aconstr;
1281 } else {
1282 return constr;
1283 }
1284 }
1285
1286 /** Return an anonymous class nested in this toplevel class.
1287 */
1288 ClassSymbol accessConstructorTag() {
1289 ClassSymbol topClass = currentClass.outermostClass();
1290 ModuleSymbol topModle = topClass.packge().modle;
1291 for (int i = 1; ; i++) {
1292 Name flatname = names.fromString("" + topClass.getQualifiedName() +
1293 target.syntheticNameChar() +
1294 i);
1295 ClassSymbol ctag = chk.getCompiled(topModle, flatname);
1296 if (ctag == null)
1297 ctag = makeEmptyClass(STATIC | SYNTHETIC, topClass).sym;
1298 else if (!ctag.isAnonymous())
1299 continue;
1300 // keep a record of all tags, to verify that all are generated as required
1301 accessConstrTags = accessConstrTags.prepend(ctag);
1302 return ctag;
1303 }
1304 }
1305
1306 /** Add all required access methods for a private symbol to enclosing class.
1307 * @param sym The symbol.
1308 */
1309 void makeAccessible(Symbol sym) {
1310 JCClassDecl cdef = classDef(sym.owner.enclClass());
1311 if (cdef == null) Assert.error("class def not found: " + sym + " in " + sym.owner);
1312 if (sym.name == names.init) {
1313 cdef.defs = cdef.defs.prepend(
1314 accessConstructorDef(cdef.pos, sym, accessConstrs.get(sym)));
1315 } else {
1316 MethodSymbol[] accessors = accessSyms.get(sym);
1317 for (int i = 0; i < AccessCode.numberOfAccessCodes; i++) {
1318 if (accessors[i] != null)
1319 cdef.defs = cdef.defs.prepend(
1320 accessDef(cdef.pos, sym, accessors[i], i));
1321 }
1322 }
1323 }
1324
1325 /** Construct definition of an access method.
1326 * @param pos The source code position of the definition.
1327 * @param vsym The private or protected symbol.
1328 * @param accessor The access method for the symbol.
1329 * @param acode The access code.
1330 */
1331 JCTree accessDef(int pos, Symbol vsym, MethodSymbol accessor, int acode) {
1332 // System.err.println("access " + vsym + " with " + accessor);//DEBUG
1333 currentClass = vsym.owner.enclClass();
1334 make.at(pos);
1335 JCMethodDecl md = make.MethodDef(accessor, null);
1336
1337 // Find actual symbol
1338 Symbol sym = actualSymbols.get(vsym);
1339 if (sym == null) sym = vsym;
1340
1341 JCExpression ref; // The tree referencing the private symbol.
1342 List<JCExpression> args; // Any additional arguments to be passed along.
1343 if ((sym.flags() & STATIC) != 0) {
1344 ref = make.Ident(sym);
1345 args = make.Idents(md.params);
1346 } else {
1347 JCExpression site = make.Ident(md.params.head);
1348 if (acode % 2 != 0) {
1349 //odd access codes represent qualified super accesses - need to
1350 //emit reference to the direct superclass, even if the referred
1351 //member is from an indirect superclass (JLS 13.1)
1352 site.setType(types.erasure(types.supertype(vsym.owner.enclClass().type)));
1353 }
1354 ref = make.Select(site, sym);
1355 args = make.Idents(md.params.tail);
1356 }
1357 JCStatement stat; // The statement accessing the private symbol.
1358 if (sym.kind == VAR) {
1359 // Normalize out all odd access codes by taking floor modulo 2:
1360 int acode1 = acode - (acode & 1);
1361
1362 JCExpression expr; // The access method's return value.
1363 AccessCode aCode = AccessCode.getFromCode(acode1);
1364 switch (aCode) {
1365 case DEREF:
1366 expr = ref;
1367 break;
1368 case ASSIGN:
1369 expr = make.Assign(ref, args.head);
1370 break;
1371 case PREINC: case POSTINC: case PREDEC: case POSTDEC:
1372 expr = makeUnary(aCode.tag, ref);
1373 break;
1374 case WITHFIELD:
1375 expr = make.WithField(ref, args.head);
1376 break;
1377 default:
1378 expr = make.Assignop(
1379 treeTag(binaryAccessOperator(acode1, JCTree.Tag.NO_TAG)), ref, args.head);
1380 ((JCAssignOp) expr).operator = binaryAccessOperator(acode1, JCTree.Tag.NO_TAG);
1381 }
1382 stat = make.Return(expr.setType(aCode == AccessCode.WITHFIELD ? sym.owner.type : sym.type));
1383 } else {
1384 stat = make.Call(make.App(ref, args));
1385 }
1386 md.body = make.Block(0, List.of(stat));
1387
1388 // Make sure all parameters, result types and thrown exceptions
1389 // are accessible.
1390 for (List<JCVariableDecl> l = md.params; l.nonEmpty(); l = l.tail)
1391 l.head.vartype = access(l.head.vartype);
1392 md.restype = access(md.restype);
1393 for (List<JCExpression> l = md.thrown; l.nonEmpty(); l = l.tail)
1394 l.head = access(l.head);
1395
1396 return md;
1397 }
1398
1399 /** Construct definition of an access constructor.
1400 * @param pos The source code position of the definition.
1401 * @param constr The private constructor.
1402 * @param accessor The access method for the constructor.
1403 */
1404 JCTree accessConstructorDef(int pos, Symbol constr, MethodSymbol accessor) {
1405 make.at(pos);
1406 JCMethodDecl md = make.MethodDef(accessor,
1407 accessor.externalType(types),
1408 null);
1409 JCIdent callee = make.Ident(names._this);
1410 callee.sym = constr;
1411 callee.type = constr.type;
1412 md.body =
1413 make.Block(0, List.of(
1414 make.Call(
1415 make.App(
1416 callee,
1417 make.Idents(md.params.reverse().tail.reverse())))));
1418 return md;
1419 }
1420
1421 /**************************************************************************
1422 * Free variables proxies and this$n
1423 *************************************************************************/
1424
1425 /** A map which allows to retrieve the translated proxy variable for any given symbol of an
1426 * enclosing scope that is accessed (the accessed symbol could be the synthetic 'this$n' symbol).
1427 * Inside a constructor, the map temporarily overrides entries corresponding to proxies and any
1428 * 'this$n' symbols, where they represent the constructor parameters.
1429 */
1430 Map<Symbol, Symbol> proxies;
1431
1432 /** A scope containing all unnamed resource variables/saved
1433 * exception variables for translated TWR blocks
1434 */
1435 WriteableScope twrVars;
1436
1437 /** A stack containing the this$n field of the currently translated
1438 * classes (if needed) in innermost first order.
1439 * Inside a constructor, proxies and any this$n symbol are duplicated
1440 * in an additional innermost scope, where they represent the constructor
1441 * parameters.
1442 */
1443 List<VarSymbol> outerThisStack;
1444
1445 /** The name of a free variable proxy.
1446 */
1447 Name proxyName(Name name, int index) {
1448 Name proxyName = names.fromString("val" + target.syntheticNameChar() + name);
1449 if (index > 0) {
1450 proxyName = proxyName.append(names.fromString("" + target.syntheticNameChar() + index));
1451 }
1452 return proxyName;
1453 }
1454
1455 /** Proxy definitions for all free variables in given list, in reverse order.
1456 * @param pos The source code position of the definition.
1457 * @param freevars The free variables.
1458 * @param owner The class in which the definitions go.
1459 */
1460 List<JCVariableDecl> freevarDefs(int pos, List<VarSymbol> freevars, Symbol owner) {
1461 return freevarDefs(pos, freevars, owner, 0);
1462 }
1463
1464 List<JCVariableDecl> freevarDefs(int pos, List<VarSymbol> freevars, Symbol owner,
1465 long additionalFlags) {
1466 long flags = FINAL | SYNTHETIC | additionalFlags;
1467 List<JCVariableDecl> defs = List.nil();
1468 Set<Name> proxyNames = new HashSet<>();
1469 for (List<VarSymbol> l = freevars; l.nonEmpty(); l = l.tail) {
1470 VarSymbol v = l.head;
1471 int index = 0;
1472 Name proxyName;
1473 do {
1474 proxyName = proxyName(v.name, index++);
1475 } while (!proxyNames.add(proxyName));
1476 final Type type = v.erasure(types);
1477 VarSymbol proxy = new VarSymbol(
1478 flags, proxyName, type, owner);
1479 proxies.put(v, proxy);
1480 JCVariableDecl vd = make.at(pos).VarDef(proxy, null);
1481 vd.vartype = access(vd.vartype);
1482 defs = defs.prepend(vd);
1483 }
1484 return defs;
1485 }
1486
1487 /** The name of a this$n field
1488 * @param type The class referenced by the this$n field
1489 */
1490 Name outerThisName(Type type, Symbol owner) {
1491 Type t = type.getEnclosingType();
1492 int nestingLevel = 0;
1493 while (t.hasTag(CLASS)) {
1494 t = t.getEnclosingType();
1495 nestingLevel++;
1496 }
1497 Name result = names.fromString("this" + target.syntheticNameChar() + nestingLevel);
1498 while (owner.kind == TYP && ((ClassSymbol)owner).members().findFirst(result) != null)
1499 result = names.fromString(result.toString() + target.syntheticNameChar());
1500 return result;
1501 }
1502
1503 private VarSymbol makeOuterThisVarSymbol(Symbol owner, long flags) {
1504 Type target = types.erasure(owner.enclClass().type.getEnclosingType());
1505 VarSymbol outerThis =
1506 new VarSymbol(flags, outerThisName(target, owner), target, owner);
1507 outerThisStack = outerThisStack.prepend(outerThis);
1508 return outerThis;
1509 }
1510
1511 private JCVariableDecl makeOuterThisVarDecl(int pos, VarSymbol sym) {
1512 JCVariableDecl vd = make.at(pos).VarDef(sym, null);
1513 vd.vartype = access(vd.vartype);
1514 return vd;
1515 }
1516
1517 /** Definition for this$n field.
1518 * @param pos The source code position of the definition.
1519 * @param owner The method in which the definition goes.
1520 */
1521 JCVariableDecl outerThisDef(int pos, MethodSymbol owner) {
1522 ClassSymbol c = owner.enclClass();
1523 boolean isMandated =
1524 // Anonymous constructors
1525 (owner.isConstructor() && owner.isAnonymous()) ||
1526 // Constructors of non-private inner member classes
1527 (owner.isConstructor() && c.isInner() &&
1528 !c.isPrivate() && !c.isStatic());
1529 long flags =
1530 FINAL | (isMandated ? MANDATED : SYNTHETIC) | PARAMETER;
1531 VarSymbol outerThis = makeOuterThisVarSymbol(owner, flags);
1532 owner.extraParams = owner.extraParams.prepend(outerThis);
1533 return makeOuterThisVarDecl(pos, outerThis);
1534 }
1535
1536 /** Definition for this$n field.
1537 * @param pos The source code position of the definition.
1538 * @param owner The class in which the definition goes.
1539 */
1540 JCVariableDecl outerThisDef(int pos, ClassSymbol owner) {
1541 Type target = types.erasure(owner.enclClass().type.getEnclosingType());
1542 long flags = FINAL | SYNTHETIC;
1543 VarSymbol outerThis = makeOuterThisVarSymbol(owner, flags);
1544 return makeOuterThisVarDecl(pos, outerThis);
1545 }
1546
1547 /** Return a list of trees that load the free variables in given list,
1548 * in reverse order.
1549 * @param pos The source code position to be used for the trees.
1550 * @param freevars The list of free variables.
1551 */
1552 List<JCExpression> loadFreevars(DiagnosticPosition pos, List<VarSymbol> freevars) {
1553 List<JCExpression> args = List.nil();
1554 for (List<VarSymbol> l = freevars; l.nonEmpty(); l = l.tail)
1555 args = args.prepend(loadFreevar(pos, l.head));
1556 return args;
1557 }
1558 //where
1559 JCExpression loadFreevar(DiagnosticPosition pos, VarSymbol v) {
1560 return access(v, make.at(pos).Ident(v), null, false);
1561 }
1562
1563 /** Construct a tree simulating the expression {@code C.this}.
1564 * @param pos The source code position to be used for the tree.
1565 * @param c The qualifier class.
1566 */
1567 JCExpression makeThis(DiagnosticPosition pos, TypeSymbol c) {
1568 if (currentClass == c) {
1569 // in this case, `this' works fine
1570 return make.at(pos).This(c.erasure(types));
1571 } else {
1572 // need to go via this$n
1573 return makeOuterThis(pos, c);
1574 }
1575 }
1576
1577 /**
1578 * Optionally replace a try statement with the desugaring of a
1579 * try-with-resources statement. The canonical desugaring of
1580 *
1581 * try ResourceSpecification
1582 * Block
1583 *
1584 * is
1585 *
1586 * {
1587 * final VariableModifiers_minus_final R #resource = Expression;
1588 *
1589 * try ResourceSpecificationtail
1590 * Block
1591 * } body-only-finally {
1592 * if (#resource != null) //nullcheck skipped if Expression is provably non-null
1593 * #resource.close();
1594 * } catch (Throwable #primaryException) {
1595 * if (#resource != null) //nullcheck skipped if Expression is provably non-null
1596 * try {
1597 * #resource.close();
1598 * } catch (Throwable #suppressedException) {
1599 * #primaryException.addSuppressed(#suppressedException);
1600 * }
1601 * throw #primaryException;
1602 * }
1603 * }
1604 *
1605 * @param tree The try statement to inspect.
1606 * @return A a desugared try-with-resources tree, or the original
1607 * try block if there are no resources to manage.
1608 */
1609 JCTree makeTwrTry(JCTry tree) {
1610 make_at(tree.pos());
1611 twrVars = twrVars.dup();
1612 JCBlock twrBlock = makeTwrBlock(tree.resources, tree.body, 0);
1613 if (tree.catchers.isEmpty() && tree.finalizer == null)
1614 result = translate(twrBlock);
1615 else
1616 result = translate(make.Try(twrBlock, tree.catchers, tree.finalizer));
1617 twrVars = twrVars.leave();
1618 return result;
1619 }
1620
1621 private JCBlock makeTwrBlock(List<JCTree> resources, JCBlock block, int depth) {
1622 if (resources.isEmpty())
1623 return block;
1624
1625 // Add resource declaration or expression to block statements
1626 ListBuffer<JCStatement> stats = new ListBuffer<>();
1627 JCTree resource = resources.head;
1628 JCExpression resourceUse;
1629 boolean resourceNonNull;
1630 if (resource instanceof JCVariableDecl variableDecl) {
1631 resourceUse = make.Ident(variableDecl.sym).setType(resource.type);
1632 resourceNonNull = variableDecl.init != null && TreeInfo.skipParens(variableDecl.init).hasTag(NEWCLASS);
1633 stats.add(variableDecl);
1634 } else {
1635 Assert.check(resource instanceof JCExpression);
1636 VarSymbol syntheticTwrVar =
1637 new VarSymbol(SYNTHETIC | FINAL,
1638 makeSyntheticName(names.fromString("twrVar" +
1639 depth), twrVars),
1640 (resource.type.hasTag(BOT)) ?
1641 syms.autoCloseableType : resource.type,
1642 currentMethodSym);
1643 twrVars.enter(syntheticTwrVar);
1644 JCVariableDecl syntheticTwrVarDecl =
1645 make.VarDef(syntheticTwrVar, (JCExpression)resource);
1646 resourceUse = (JCExpression)make.Ident(syntheticTwrVar);
1647 resourceNonNull = false;
1648 stats.add(syntheticTwrVarDecl);
1649 }
1650
1651 //create (semi-) finally block that will be copied into the main try body:
1652 int oldPos = make.pos;
1653 make.at(TreeInfo.endPos(block));
1654
1655 // if (#resource != null) { #resource.close(); }
1656 JCStatement bodyCloseStatement = makeResourceCloseInvocation(resourceUse);
1657
1658 if (!resourceNonNull) {
1659 bodyCloseStatement = make.If(makeNonNullCheck(resourceUse),
1660 bodyCloseStatement,
1661 null);
1662 }
1663
1664 JCBlock finallyClause = make.Block(BODY_ONLY_FINALIZE, List.of(bodyCloseStatement));
1665 make.at(oldPos);
1666
1667 // Create catch clause that saves exception, closes the resource and then rethrows the exception:
1668 VarSymbol primaryException =
1669 new VarSymbol(FINAL|SYNTHETIC,
1670 names.fromString("t" +
1671 target.syntheticNameChar()),
1672 syms.throwableType,
1673 currentMethodSym);
1674 JCVariableDecl primaryExceptionDecl = make.VarDef(primaryException, null);
1675
1676 // close resource:
1677 // try {
1678 // #resource.close();
1679 // } catch (Throwable #suppressedException) {
1680 // #primaryException.addSuppressed(#suppressedException);
1681 // }
1682 VarSymbol suppressedException =
1683 new VarSymbol(SYNTHETIC, make.paramName(2),
1684 syms.throwableType,
1685 currentMethodSym);
1686 JCStatement addSuppressedStatement =
1687 make.Exec(makeCall(make.Ident(primaryException),
1688 names.addSuppressed,
1689 List.of(make.Ident(suppressedException))));
1690 JCBlock closeResourceTryBlock =
1691 make.Block(0L, List.of(makeResourceCloseInvocation(resourceUse)));
1692 JCVariableDecl catchSuppressedDecl = make.VarDef(suppressedException, null);
1693 JCBlock catchSuppressedBlock = make.Block(0L, List.of(addSuppressedStatement));
1694 List<JCCatch> catchSuppressedClauses =
1695 List.of(make.Catch(catchSuppressedDecl, catchSuppressedBlock));
1696 JCTry closeResourceTry = make.Try(closeResourceTryBlock, catchSuppressedClauses, null);
1697 closeResourceTry.finallyCanCompleteNormally = true;
1698
1699 JCStatement exceptionalCloseStatement = closeResourceTry;
1700
1701 if (!resourceNonNull) {
1702 // if (#resource != null) { }
1703 exceptionalCloseStatement = make.If(makeNonNullCheck(resourceUse),
1704 exceptionalCloseStatement,
1705 null);
1706 }
1707
1708 JCStatement exceptionalRethrow = make.Throw(make.Ident(primaryException));
1709 JCBlock exceptionalCloseBlock = make.Block(0L, List.of(exceptionalCloseStatement, exceptionalRethrow));
1710 JCCatch exceptionalCatchClause = make.Catch(primaryExceptionDecl, exceptionalCloseBlock);
1711
1712 //create the main try statement with the close:
1713 JCTry outerTry = make.Try(makeTwrBlock(resources.tail, block, depth + 1),
1714 List.of(exceptionalCatchClause),
1715 finallyClause);
1716
1717 outerTry.finallyCanCompleteNormally = true;
1718 stats.add(outerTry);
1719
1720 JCBlock newBlock = make.Block(0L, stats.toList());
1721 return newBlock;
1722 }
1723
1724 private JCStatement makeResourceCloseInvocation(JCExpression resource) {
1725 // convert to AutoCloseable if needed
1726 if (types.asSuper(resource.type.referenceProjectionOrSelf(), syms.autoCloseableType.tsym) == null) {
1727 resource = convert(resource, syms.autoCloseableType);
1728 }
1729
1730 // create resource.close() method invocation
1731 JCExpression resourceClose = makeCall(resource,
1732 names.close,
1733 List.nil());
1734 return make.Exec(resourceClose);
1735 }
1736
1737 private JCExpression makeNonNullCheck(JCExpression expression) {
1738 return makeBinary(NE, expression, makeNull());
1739 }
1740
1741 /** Construct a tree that represents the outer instance
1742 * {@code C.this}. Never pick the current `this'.
1743 * @param pos The source code position to be used for the tree.
1744 * @param c The qualifier class.
1745 */
1746 JCExpression makeOuterThis(DiagnosticPosition pos, TypeSymbol c) {
1747 List<VarSymbol> ots = outerThisStack;
1748 if (ots.isEmpty()) {
1749 log.error(pos, Errors.NoEnclInstanceOfTypeInScope(c));
1750 Assert.error();
1751 return makeNull();
1752 }
1753 VarSymbol ot = ots.head;
1754 JCExpression tree = access(make.at(pos).Ident(ot));
1755 TypeSymbol otc = ot.type.tsym;
1756 while (otc != c) {
1757 do {
1758 ots = ots.tail;
1759 if (ots.isEmpty()) {
1760 log.error(pos, Errors.NoEnclInstanceOfTypeInScope(c));
1761 Assert.error(); // should have been caught in Attr
1762 return tree;
1763 }
1764 ot = ots.head;
1765 } while (ot.owner != otc);
1766 if (otc.owner.kind != PCK && !otc.hasOuterInstance()) {
1767 chk.earlyRefError(pos, c);
1768 Assert.error(); // should have been caught in Attr
1769 return makeNull();
1770 }
1771 tree = access(make.at(pos).Select(tree, ot));
1772 otc = ot.type.tsym;
1773 }
1774 return tree;
1775 }
1776
1777 /** Construct a tree that represents the closest outer instance
1778 * {@code C.this} such that the given symbol is a member of C.
1779 * @param pos The source code position to be used for the tree.
1780 * @param sym The accessed symbol.
1781 * @param preciseMatch should we accept a type that is a subtype of
1782 * sym's owner, even if it doesn't contain sym
1783 * due to hiding, overriding, or non-inheritance
1784 * due to protection?
1785 */
1786 JCExpression makeOwnerThis(DiagnosticPosition pos, Symbol sym, boolean preciseMatch) {
1787 Symbol c = sym.owner;
1788 if (preciseMatch ? sym.isMemberOf(currentClass, types)
1789 : currentClass.isSubClass(sym.owner, types)) {
1790 // in this case, `this' works fine
1791 return make.at(pos).This(c.erasure(types));
1792 } else {
1793 // need to go via this$n
1794 return makeOwnerThisN(pos, sym, preciseMatch);
1795 }
1796 }
1797
1798 /**
1799 * Similar to makeOwnerThis but will never pick "this".
1800 */
1801 JCExpression makeOwnerThisN(DiagnosticPosition pos, Symbol sym, boolean preciseMatch) {
1802 Symbol c = sym.owner;
1803 List<VarSymbol> ots = outerThisStack;
1804 if (ots.isEmpty()) {
1805 log.error(pos, Errors.NoEnclInstanceOfTypeInScope(c));
1806 Assert.error();
1807 return makeNull();
1808 }
1809 VarSymbol ot = ots.head;
1810 JCExpression tree = access(make.at(pos).Ident(ot));
1811 TypeSymbol otc = ot.type.tsym;
1812 while (!(preciseMatch ? sym.isMemberOf(otc, types) : otc.isSubClass(sym.owner, types))) {
1813 do {
1814 ots = ots.tail;
1815 if (ots.isEmpty()) {
1816 log.error(pos, Errors.NoEnclInstanceOfTypeInScope(c));
1817 Assert.error();
1818 return tree;
1819 }
1820 ot = ots.head;
1821 } while (ot.owner != otc);
1822 tree = access(make.at(pos).Select(tree, ot));
1823 otc = ot.type.tsym;
1824 }
1825 return tree;
1826 }
1827
1828 /** Return tree simulating the assignment {@code this.name = name}, where
1829 * name is the name of a free variable.
1830 */
1831 JCStatement initField(int pos, Symbol rhs, Symbol lhs) {
1832 Assert.check(rhs.owner.kind == MTH);
1833 Assert.check(rhs.owner.owner == lhs.owner);
1834 make.at(pos);
1835 return
1836 make.Exec(
1837 make.Assign(
1838 make.Select(make.This(lhs.owner.erasure(types)), lhs),
1839 make.Ident(rhs)).setType(lhs.erasure(types)));
1840 }
1841
1842 /** Return tree simulating the assignment {@code this.this$n = this$n}.
1843 */
1844 JCStatement initOuterThis(int pos) {
1845 VarSymbol rhs = outerThisStack.head;
1846 Assert.check(rhs.owner.kind == MTH);
1847 VarSymbol lhs = outerThisStack.tail.head;
1848 Assert.check(rhs.owner.owner == lhs.owner);
1849 make.at(pos);
1850 return
1851 make.Exec(
1852 make.Assign(
1853 make.Select(make.This(lhs.owner.erasure(types)), lhs),
1854 make.Ident(rhs)).setType(lhs.erasure(types)));
1855 }
1856
1857 /**************************************************************************
1858 * Code for .class
1859 *************************************************************************/
1860
1861 /** Return the symbol of a class to contain a cache of
1862 * compiler-generated statics such as class$ and the
1863 * $assertionsDisabled flag. We create an anonymous nested class
1864 * (unless one already exists) and return its symbol. However,
1865 * for backward compatibility in 1.4 and earlier we use the
1866 * top-level class itself.
1867 */
1868 private ClassSymbol outerCacheClass() {
1869 ClassSymbol clazz = outermostClassDef.sym;
1870 Scope s = clazz.members();
1871 for (Symbol sym : s.getSymbols(NON_RECURSIVE))
1872 if (sym.kind == TYP &&
1873 sym.name == names.empty &&
1874 (sym.flags() & INTERFACE) == 0) return (ClassSymbol) sym;
1875 return makeEmptyClass(STATIC | SYNTHETIC, clazz).sym;
1876 }
1877
1878 /** Create an attributed tree of the form left.name(). */
1879 private JCMethodInvocation makeCall(JCExpression left, Name name, List<JCExpression> args) {
1880 Assert.checkNonNull(left.type);
1881 Symbol funcsym = lookupMethod(make_pos, name, left.type,
1882 TreeInfo.types(args));
1883 return make.App(make.Select(left, funcsym), args);
1884 }
1885
1886 /** The tree simulating a T.class expression.
1887 * @param clazz The tree identifying type T.
1888 */
1889 private JCExpression classOf(JCTree clazz) {
1890 return classOfType(clazz.type, clazz.pos());
1891 }
1892
1893 private JCExpression classOfType(Type type, DiagnosticPosition pos) {
1894 switch (type.getTag()) {
1895 case BYTE: case SHORT: case CHAR: case INT: case LONG: case FLOAT:
1896 case DOUBLE: case BOOLEAN: case VOID:
1897 // replace with <BoxedClass>.TYPE
1898 ClassSymbol c = types.boxedClass(type);
1899 Symbol typeSym =
1900 rs.accessBase(
1901 rs.findIdentInType(pos, attrEnv, c.type, names.TYPE, KindSelector.VAR),
1902 pos, c.type, names.TYPE, true);
1903 if (typeSym.kind == VAR)
1904 ((VarSymbol)typeSym).getConstValue(); // ensure initializer is evaluated
1905 return make.QualIdent(typeSym);
1906 case CLASS: case ARRAY:
1907 VarSymbol sym = new VarSymbol(
1908 STATIC | PUBLIC | FINAL, names._class,
1909 syms.classType, type.tsym);
1910 return make_at(pos).Select(make.Type(type), sym);
1911 default:
1912 throw new AssertionError();
1913 }
1914 }
1915
1916 /**************************************************************************
1917 * Code for enabling/disabling assertions.
1918 *************************************************************************/
1919
1920 private ClassSymbol assertionsDisabledClassCache;
1921
1922 /**Used to create an auxiliary class to hold $assertionsDisabled for interfaces.
1923 */
1924 private ClassSymbol assertionsDisabledClass() {
1925 if (assertionsDisabledClassCache != null) return assertionsDisabledClassCache;
1926
1927 assertionsDisabledClassCache = makeEmptyClass(STATIC | SYNTHETIC, outermostClassDef.sym).sym;
1928
1929 return assertionsDisabledClassCache;
1930 }
1931
1932 // This code is not particularly robust if the user has
1933 // previously declared a member named '$assertionsDisabled'.
1934 // The same faulty idiom also appears in the translation of
1935 // class literals above. We should report an error if a
1936 // previous declaration is not synthetic.
1937
1938 private JCExpression assertFlagTest(DiagnosticPosition pos) {
1939 // Outermost class may be either true class or an interface.
1940 ClassSymbol outermostClass = outermostClassDef.sym;
1941
1942 //only classes can hold a non-public field, look for a usable one:
1943 ClassSymbol container = !currentClass.isInterface() ? currentClass :
1944 assertionsDisabledClass();
1945
1946 VarSymbol assertDisabledSym =
1947 (VarSymbol)lookupSynthetic(dollarAssertionsDisabled,
1948 container.members());
1949 if (assertDisabledSym == null) {
1950 assertDisabledSym =
1951 new VarSymbol(STATIC | FINAL | SYNTHETIC,
1952 dollarAssertionsDisabled,
1953 syms.booleanType,
1954 container);
1955 enterSynthetic(pos, assertDisabledSym, container.members());
1956 Symbol desiredAssertionStatusSym = lookupMethod(pos,
1957 names.desiredAssertionStatus,
1958 types.erasure(syms.classType),
1959 List.nil());
1960 JCClassDecl containerDef = classDef(container);
1961 make_at(containerDef.pos());
1962 JCExpression notStatus = makeUnary(NOT, make.App(make.Select(
1963 classOfType(types.erasure(outermostClass.type),
1964 containerDef.pos()),
1965 desiredAssertionStatusSym)));
1966 JCVariableDecl assertDisabledDef = make.VarDef(assertDisabledSym,
1967 notStatus);
1968 containerDef.defs = containerDef.defs.prepend(assertDisabledDef);
1969
1970 if (currentClass.isInterface()) {
1971 //need to load the assertions enabled/disabled state while
1972 //initializing the interface:
1973 JCClassDecl currentClassDef = classDef(currentClass);
1974 make_at(currentClassDef.pos());
1975 JCStatement dummy = make.If(make.QualIdent(assertDisabledSym), make.Skip(), null);
1976 JCBlock clinit = make.Block(STATIC, List.of(dummy));
1977 currentClassDef.defs = currentClassDef.defs.prepend(clinit);
1978 }
1979 }
1980 make_at(pos);
1981 return makeUnary(NOT, make.Ident(assertDisabledSym));
1982 }
1983
1984
1985 /**************************************************************************
1986 * Building blocks for let expressions
1987 *************************************************************************/
1988
1989 interface TreeBuilder {
1990 JCExpression build(JCExpression arg);
1991 }
1992
1993 /** Construct an expression using the builder, with the given rval
1994 * expression as an argument to the builder. However, the rval
1995 * expression must be computed only once, even if used multiple
1996 * times in the result of the builder. We do that by
1997 * constructing a "let" expression that saves the rvalue into a
1998 * temporary variable and then uses the temporary variable in
1999 * place of the expression built by the builder. The complete
2000 * resulting expression is of the form
2001 * <pre>
2002 * (let <b>TYPE</b> <b>TEMP</b> = <b>RVAL</b>;
2003 * in (<b>BUILDER</b>(<b>TEMP</b>)))
2004 * </pre>
2005 * where <code><b>TEMP</b></code> is a newly declared variable
2006 * in the let expression.
2007 */
2008 JCExpression abstractRval(JCExpression rval, Type type, TreeBuilder builder) {
2009 rval = TreeInfo.skipParens(rval);
2010 switch (rval.getTag()) {
2011 case LITERAL:
2012 return builder.build(rval);
2013 case IDENT:
2014 JCIdent id = (JCIdent) rval;
2015 if ((id.sym.flags() & FINAL) != 0 && id.sym.owner.kind == MTH)
2016 return builder.build(rval);
2017 }
2018 Name name = TreeInfo.name(rval);
2019 if (name == names._super || name == names._this)
2020 return builder.build(rval);
2021 VarSymbol var =
2022 new VarSymbol(FINAL|SYNTHETIC,
2023 names.fromString(
2024 target.syntheticNameChar()
2025 + "" + rval.hashCode()),
2026 type,
2027 currentMethodSym);
2028 rval = convert(rval,type);
2029 JCVariableDecl def = make.VarDef(var, rval); // XXX cast
2030 JCExpression built = builder.build(make.Ident(var));
2031 JCExpression res = make.LetExpr(def, built);
2032 res.type = built.type;
2033 return res;
2034 }
2035
2036 // same as above, with the type of the temporary variable computed
2037 JCExpression abstractRval(JCExpression rval, TreeBuilder builder) {
2038 return abstractRval(rval, rval.type, builder);
2039 }
2040
2041 // same as above, but for an expression that may be used as either
2042 // an rvalue or an lvalue. This requires special handling for
2043 // Select expressions, where we place the left-hand-side of the
2044 // select in a temporary, and for Indexed expressions, where we
2045 // place both the indexed expression and the index value in temps.
2046 JCExpression abstractLval(JCExpression lval, final TreeBuilder builder) {
2047 lval = TreeInfo.skipParens(lval);
2048 switch (lval.getTag()) {
2049 case IDENT:
2050 return builder.build(lval);
2051 case SELECT: {
2052 final JCFieldAccess s = (JCFieldAccess)lval;
2053 Symbol lid = TreeInfo.symbol(s.selected);
2054 if (lid != null && lid.kind == TYP) return builder.build(lval);
2055 return abstractRval(s.selected, selected -> builder.build(make.Select(selected, s.sym)));
2056 }
2057 case INDEXED: {
2058 final JCArrayAccess i = (JCArrayAccess)lval;
2059 return abstractRval(i.indexed, indexed -> abstractRval(i.index, syms.intType, index -> {
2060 JCExpression newLval = make.Indexed(indexed, index);
2061 newLval.setType(i.type);
2062 return builder.build(newLval);
2063 }));
2064 }
2065 case TYPECAST: {
2066 return abstractLval(((JCTypeCast)lval).expr, builder);
2067 }
2068 }
2069 throw new AssertionError(lval);
2070 }
2071
2072 // evaluate and discard the first expression, then evaluate the second.
2073 JCExpression makeComma(final JCExpression expr1, final JCExpression expr2) {
2074 JCExpression res = make.LetExpr(List.of(make.Exec(expr1)), expr2);
2075 res.type = expr2.type;
2076 return res;
2077 }
2078
2079 /**************************************************************************
2080 * Translation methods
2081 *************************************************************************/
2082
2083 /** Visitor argument: enclosing operator node.
2084 */
2085 private JCExpression enclOp;
2086
2087 /** Visitor method: Translate a single node.
2088 * Attach the source position from the old tree to its replacement tree.
2089 */
2090 @Override
2091 public <T extends JCTree> T translate(T tree) {
2092 if (tree == null) {
2093 return null;
2094 } else {
2095 make_at(tree.pos());
2096 T result = super.translate(tree);
2097 if (endPosTable != null && result != tree) {
2098 endPosTable.replaceTree(tree, result);
2099 }
2100 return result;
2101 }
2102 }
2103
2104 /** Visitor method: Translate a single node, boxing or unboxing if needed.
2105 */
2106 public <T extends JCExpression> T translate(T tree, Type type) {
2107 return (tree == null) ? null :
2108 applyPrimitiveConversionsAsNeeded(boxIfNeeded(translate(tree), type), type);
2109 }
2110
2111 /** Visitor method: Translate tree.
2112 */
2113 public <T extends JCTree> T translate(T tree, JCExpression enclOp) {
2114 JCExpression prevEnclOp = this.enclOp;
2115 this.enclOp = enclOp;
2116 T res = translate(tree);
2117 this.enclOp = prevEnclOp;
2118 return res;
2119 }
2120
2121 /** Visitor method: Translate list of trees.
2122 */
2123 public <T extends JCExpression> List<T> translate(List<T> trees, Type type) {
2124 if (trees == null) return null;
2125 for (List<T> l = trees; l.nonEmpty(); l = l.tail)
2126 l.head = translate(l.head, type);
2127 return trees;
2128 }
2129
2130 public void visitPackageDef(JCPackageDecl tree) {
2131 if (!needPackageInfoClass(tree))
2132 return;
2133
2134 long flags = Flags.ABSTRACT | Flags.INTERFACE;
2135 // package-info is marked SYNTHETIC in JDK 1.6 and later releases
2136 flags = flags | Flags.SYNTHETIC;
2137 ClassSymbol c = tree.packge.package_info;
2138 c.setAttributes(tree.packge);
2139 c.flags_field |= flags;
2140 ClassType ctype = (ClassType) c.type;
2141 ctype.supertype_field = syms.objectType;
2142 ctype.interfaces_field = List.nil();
2143 createInfoClass(tree.annotations, c);
2144 }
2145 // where
2146 private boolean needPackageInfoClass(JCPackageDecl pd) {
2147 switch (pkginfoOpt) {
2148 case ALWAYS:
2149 return true;
2150 case LEGACY:
2151 return pd.getAnnotations().nonEmpty();
2152 case NONEMPTY:
2153 for (Attribute.Compound a :
2154 pd.packge.getDeclarationAttributes()) {
2155 Attribute.RetentionPolicy p = types.getRetention(a);
2156 if (p != Attribute.RetentionPolicy.SOURCE)
2157 return true;
2158 }
2159 return false;
2160 }
2161 throw new AssertionError();
2162 }
2163
2164 public void visitModuleDef(JCModuleDecl tree) {
2165 ModuleSymbol msym = tree.sym;
2166 ClassSymbol c = msym.module_info;
2167 c.setAttributes(msym);
2168 c.flags_field |= Flags.MODULE;
2169 createInfoClass(List.nil(), tree.sym.module_info);
2170 }
2171
2172 private void createInfoClass(List<JCAnnotation> annots, ClassSymbol c) {
2173 long flags = Flags.ABSTRACT | Flags.INTERFACE;
2174 JCClassDecl infoClass =
2175 make.ClassDef(make.Modifiers(flags, annots),
2176 c.name, List.nil(),
2177 null, List.nil(), List.nil());
2178 infoClass.sym = c;
2179 translated.append(infoClass);
2180 }
2181
2182 public void visitClassDef(JCClassDecl tree) {
2183 Env<AttrContext> prevEnv = attrEnv;
2184 ClassSymbol currentClassPrev = currentClass;
2185 MethodSymbol currentMethodSymPrev = currentMethodSym;
2186
2187 currentClass = tree.sym;
2188 currentMethodSym = null;
2189 attrEnv = typeEnvs.remove(currentClass);
2190 if (attrEnv == null)
2191 attrEnv = prevEnv;
2192
2193 classdefs.put(currentClass, tree);
2194
2195 Map<Symbol, Symbol> prevProxies = proxies;
2196 proxies = new HashMap<>(proxies);
2197 List<VarSymbol> prevOuterThisStack = outerThisStack;
2198
2199 // If this is an enum definition
2200 if ((tree.mods.flags & ENUM) != 0 &&
2201 (types.supertype(currentClass.type).tsym.flags() & ENUM) == 0)
2202 visitEnumDef(tree);
2203
2204 if ((tree.mods.flags & RECORD) != 0) {
2205 visitRecordDef(tree);
2206 }
2207
2208 // If this is a nested class, define a this$n field for
2209 // it and add to proxies.
2210 JCVariableDecl otdef = null;
2211 if (currentClass.hasOuterInstance())
2212 otdef = outerThisDef(tree.pos, currentClass);
2213
2214 // If this is a local class, define proxies for all its free variables.
2215 List<JCVariableDecl> fvdefs = freevarDefs(
2216 tree.pos, freevars(currentClass), currentClass);
2217
2218 // Recursively translate superclass, interfaces.
2219 tree.extending = translate(tree.extending);
2220 tree.implementing = translate(tree.implementing);
2221
2222 if (currentClass.isDirectlyOrIndirectlyLocal()) {
2223 ClassSymbol encl = currentClass.owner.enclClass();
2224 if (encl.trans_local == null) {
2225 encl.trans_local = List.nil();
2226 }
2227 encl.trans_local = encl.trans_local.prepend(currentClass);
2228 }
2229
2230 // Recursively translate members, taking into account that new members
2231 // might be created during the translation and prepended to the member
2232 // list `tree.defs'.
2233 List<JCTree> seen = List.nil();
2234 while (tree.defs != seen) {
2235 List<JCTree> unseen = tree.defs;
2236 for (List<JCTree> l = unseen; l.nonEmpty() && l != seen; l = l.tail) {
2237 JCTree outermostMemberDefPrev = outermostMemberDef;
2238 if (outermostMemberDefPrev == null) outermostMemberDef = l.head;
2239 l.head = translate(l.head);
2240 outermostMemberDef = outermostMemberDefPrev;
2241 }
2242 seen = unseen;
2243 }
2244
2245 // Convert a protected modifier to public, mask static modifier.
2246 if ((tree.mods.flags & PROTECTED) != 0) tree.mods.flags |= PUBLIC;
2247 tree.mods.flags &= ClassFlags;
2248
2249 // Convert name to flat representation, replacing '.' by '$'.
2250 tree.name = Convert.shortName(currentClass.flatName());
2251
2252 // Add this$n and free variables proxy definitions to class.
2253
2254 for (List<JCVariableDecl> l = fvdefs; l.nonEmpty(); l = l.tail) {
2255 tree.defs = tree.defs.prepend(l.head);
2256 enterSynthetic(tree.pos(), l.head.sym, currentClass.members());
2257 }
2258 if (currentClass.hasOuterInstance()) {
2259 tree.defs = tree.defs.prepend(otdef);
2260 enterSynthetic(tree.pos(), otdef.sym, currentClass.members());
2261 }
2262
2263 proxies = prevProxies;
2264 outerThisStack = prevOuterThisStack;
2265
2266 // Append translated tree to `translated' queue.
2267 translated.append(tree);
2268
2269 attrEnv = prevEnv;
2270 currentClass = currentClassPrev;
2271 currentMethodSym = currentMethodSymPrev;
2272
2273 // Return empty block {} as a placeholder for an inner class.
2274 result = make_at(tree.pos()).Block(SYNTHETIC, List.nil());
2275 }
2276
2277 List<JCTree> generateMandatedAccessors(JCClassDecl tree) {
2278 List<JCVariableDecl> fields = TreeInfo.recordFields(tree);
2279 return tree.sym.getRecordComponents().stream()
2280 .filter(rc -> (rc.accessor.flags() & Flags.GENERATED_MEMBER) != 0)
2281 .map(rc -> {
2282 // we need to return the field not the record component
2283 JCVariableDecl field = fields.stream().filter(f -> f.name == rc.name).findAny().get();
2284 make_at(tree.pos());
2285 return make.MethodDef(rc.accessor, make.Block(0,
2286 List.of(make.Return(make.Ident(field)))));
2287 }).collect(List.collector());
2288 }
2289
2290 /** Translate an enum class. */
2291 private void visitEnumDef(JCClassDecl tree) {
2292 make_at(tree.pos());
2293
2294 // add the supertype, if needed
2295 if (tree.extending == null)
2296 tree.extending = make.Type(types.supertype(tree.type));
2297
2298 // classOfType adds a cache field to tree.defs
2299 JCExpression e_class = classOfType(tree.sym.type, tree.pos()).
2300 setType(types.erasure(syms.classType));
2301
2302 // process each enumeration constant, adding implicit constructor parameters
2303 int nextOrdinal = 0;
2304 ListBuffer<JCExpression> values = new ListBuffer<>();
2305 ListBuffer<JCTree> enumDefs = new ListBuffer<>();
2306 ListBuffer<JCTree> otherDefs = new ListBuffer<>();
2307 for (List<JCTree> defs = tree.defs;
2308 defs.nonEmpty();
2309 defs=defs.tail) {
2310 if (defs.head.hasTag(VARDEF) && (((JCVariableDecl) defs.head).mods.flags & ENUM) != 0) {
2311 JCVariableDecl var = (JCVariableDecl)defs.head;
2312 visitEnumConstantDef(var, nextOrdinal++);
2313 values.append(make.QualIdent(var.sym));
2314 enumDefs.append(var);
2315 } else {
2316 otherDefs.append(defs.head);
2317 }
2318 }
2319
2320 // synthetic private static T[] $values() { return new T[] { a, b, c }; }
2321 // synthetic private static final T[] $VALUES = $values();
2322 Name valuesName = syntheticName(tree, "VALUES");
2323 Type arrayType = new ArrayType(types.erasure(tree.type), syms.arrayClass);
2324 VarSymbol valuesVar = new VarSymbol(PRIVATE|FINAL|STATIC|SYNTHETIC,
2325 valuesName,
2326 arrayType,
2327 tree.type.tsym);
2328 JCNewArray newArray = make.NewArray(make.Type(types.erasure(tree.type)),
2329 List.nil(),
2330 values.toList());
2331 newArray.type = arrayType;
2332
2333 MethodSymbol valuesMethod = new MethodSymbol(PRIVATE|STATIC|SYNTHETIC,
2334 syntheticName(tree, "values"),
2335 new MethodType(List.nil(), arrayType, List.nil(), tree.type.tsym),
2336 tree.type.tsym);
2337 enumDefs.append(make.MethodDef(valuesMethod, make.Block(0, List.of(make.Return(newArray)))));
2338 tree.sym.members().enter(valuesMethod);
2339
2340 enumDefs.append(make.VarDef(valuesVar, make.App(make.QualIdent(valuesMethod))));
2341 tree.sym.members().enter(valuesVar);
2342
2343 Symbol valuesSym = lookupMethod(tree.pos(), names.values,
2344 tree.type, List.nil());
2345 List<JCStatement> valuesBody;
2346 if (useClone()) {
2347 // return (T[]) $VALUES.clone();
2348 JCTypeCast valuesResult =
2349 make.TypeCast(valuesSym.type.getReturnType(),
2350 make.App(make.Select(make.Ident(valuesVar),
2351 syms.arrayCloneMethod)));
2352 valuesBody = List.of(make.Return(valuesResult));
2353 } else {
2354 // template: T[] $result = new T[$values.length];
2355 Name resultName = syntheticName(tree, "result");
2356 VarSymbol resultVar = new VarSymbol(FINAL|SYNTHETIC,
2357 resultName,
2358 arrayType,
2359 valuesSym);
2360 JCNewArray resultArray = make.NewArray(make.Type(types.erasure(tree.type)),
2361 List.of(make.Select(make.Ident(valuesVar), syms.lengthVar)),
2362 null);
2363 resultArray.type = arrayType;
2364 JCVariableDecl decl = make.VarDef(resultVar, resultArray);
2365
2366 // template: System.arraycopy($VALUES, 0, $result, 0, $VALUES.length);
2367 if (systemArraycopyMethod == null) {
2368 systemArraycopyMethod =
2369 new MethodSymbol(PUBLIC | STATIC,
2370 names.fromString("arraycopy"),
2371 new MethodType(List.of(syms.objectType,
2372 syms.intType,
2373 syms.objectType,
2374 syms.intType,
2375 syms.intType),
2376 syms.voidType,
2377 List.nil(),
2378 syms.methodClass),
2379 syms.systemType.tsym);
2380 }
2381 JCStatement copy =
2382 make.Exec(make.App(make.Select(make.Ident(syms.systemType.tsym),
2383 systemArraycopyMethod),
2384 List.of(make.Ident(valuesVar), make.Literal(0),
2385 make.Ident(resultVar), make.Literal(0),
2386 make.Select(make.Ident(valuesVar), syms.lengthVar))));
2387
2388 // template: return $result;
2389 JCStatement ret = make.Return(make.Ident(resultVar));
2390 valuesBody = List.of(decl, copy, ret);
2391 }
2392
2393 JCMethodDecl valuesDef =
2394 make.MethodDef((MethodSymbol)valuesSym, make.Block(0, valuesBody));
2395
2396 enumDefs.append(valuesDef);
2397
2398 if (debugLower)
2399 System.err.println(tree.sym + ".valuesDef = " + valuesDef);
2400
2401 /** The template for the following code is:
2402 *
2403 * public static E valueOf(String name) {
2404 * return (E)Enum.valueOf(E.class, name);
2405 * }
2406 *
2407 * where E is tree.sym
2408 */
2409 MethodSymbol valueOfSym = lookupMethod(tree.pos(),
2410 names.valueOf,
2411 tree.sym.type,
2412 List.of(syms.stringType));
2413 Assert.check((valueOfSym.flags() & STATIC) != 0);
2414 VarSymbol nameArgSym = valueOfSym.params.head;
2415 JCIdent nameVal = make.Ident(nameArgSym);
2416 JCStatement enum_ValueOf =
2417 make.Return(make.TypeCast(tree.sym.type,
2418 makeCall(make.Ident(syms.enumSym),
2419 names.valueOf,
2420 List.of(e_class, nameVal))));
2421 JCMethodDecl valueOf = make.MethodDef(valueOfSym,
2422 make.Block(0, List.of(enum_ValueOf)));
2423 nameVal.sym = valueOf.params.head.sym;
2424 if (debugLower)
2425 System.err.println(tree.sym + ".valueOf = " + valueOf);
2426 enumDefs.append(valueOf);
2427
2428 enumDefs.appendList(otherDefs.toList());
2429 tree.defs = enumDefs.toList();
2430 }
2431 // where
2432 private MethodSymbol systemArraycopyMethod;
2433 private boolean useClone() {
2434 try {
2435 return syms.objectType.tsym.members().findFirst(names.clone) != null;
2436 }
2437 catch (CompletionFailure e) {
2438 return false;
2439 }
2440 }
2441
2442 private Name syntheticName(JCClassDecl tree, String baseName) {
2443 Name valuesName = names.fromString(target.syntheticNameChar() + baseName);
2444 while (tree.sym.members().findFirst(valuesName) != null) // avoid name clash
2445 valuesName = names.fromString(valuesName + "" + target.syntheticNameChar());
2446 return valuesName;
2447 }
2448
2449 /** Translate an enumeration constant and its initializer. */
2450 private void visitEnumConstantDef(JCVariableDecl var, int ordinal) {
2451 JCNewClass varDef = (JCNewClass)var.init;
2452 varDef.args = varDef.args.
2453 prepend(makeLit(syms.intType, ordinal)).
2454 prepend(makeLit(syms.stringType, var.name.toString()));
2455 }
2456
2457 private List<VarSymbol> recordVars(Type t) {
2458 List<VarSymbol> vars = List.nil();
2459 while (!t.hasTag(NONE)) {
2460 if (t.hasTag(CLASS)) {
2461 for (Symbol s : t.tsym.members().getSymbols(s -> s.kind == VAR && (s.flags() & RECORD) != 0)) {
2462 vars = vars.prepend((VarSymbol)s);
2463 }
2464 }
2465 t = types.supertype(t);
2466 }
2467 return vars;
2468 }
2469
2470 /** Translate a record. */
2471 private void visitRecordDef(JCClassDecl tree) {
2472 make_at(tree.pos());
2473 List<VarSymbol> vars = recordVars(tree.type);
2474 MethodHandleSymbol[] getterMethHandles = new MethodHandleSymbol[vars.size()];
2475 int index = 0;
2476 for (VarSymbol var : vars) {
2477 if (var.owner != tree.sym) {
2478 var = new VarSymbol(var.flags_field, var.name, var.type, tree.sym);
2479 }
2480 getterMethHandles[index] = var.asMethodHandle(true);
2481 index++;
2482 }
2483
2484 tree.defs = tree.defs.appendList(generateMandatedAccessors(tree));
2485 tree.defs = tree.defs.appendList(List.of(
2486 generateRecordMethod(tree, names.toString, vars, getterMethHandles),
2487 generateRecordMethod(tree, names.hashCode, vars, getterMethHandles),
2488 generateRecordMethod(tree, names.equals, vars, getterMethHandles)
2489 ));
2490 }
2491
2492 JCTree generateRecordMethod(JCClassDecl tree, Name name, List<VarSymbol> vars, MethodHandleSymbol[] getterMethHandles) {
2493 make_at(tree.pos());
2494 boolean isEquals = name == names.equals;
2495 MethodSymbol msym = lookupMethod(tree.pos(),
2496 name,
2497 tree.sym.type,
2498 isEquals ? List.of(syms.objectType) : List.nil());
2499 // compiler generated methods have the record flag set, user defined ones dont
2500 if ((msym.flags() & RECORD) != 0) {
2501 /* class java.lang.runtime.ObjectMethods provides a common bootstrap that provides a customized implementation
2502 * for methods: toString, hashCode and equals. Here we just need to generate and indy call to:
2503 * java.lang.runtime.ObjectMethods::bootstrap and provide: the record class, the record component names and
2504 * the accessors.
2505 */
2506 Name bootstrapName = names.bootstrap;
2507 LoadableConstant[] staticArgsValues = new LoadableConstant[2 + getterMethHandles.length];
2508 staticArgsValues[0] = (ClassType)tree.sym.type;
2509 String concatNames = vars.stream()
2510 .map(v -> v.name)
2511 .collect(Collectors.joining(";", "", ""));
2512 staticArgsValues[1] = LoadableConstant.String(concatNames);
2513 int index = 2;
2514 for (MethodHandleSymbol mho : getterMethHandles) {
2515 staticArgsValues[index] = mho;
2516 index++;
2517 }
2518
2519 List<Type> staticArgTypes = List.of(syms.classType,
2520 syms.stringType,
2521 new ArrayType(syms.methodHandleType, syms.arrayClass));
2522
2523 JCFieldAccess qualifier = makeIndyQualifier(syms.objectMethodsType, tree, msym,
2524 List.of(syms.methodHandleLookupType,
2525 syms.stringType,
2526 syms.typeDescriptorType).appendList(staticArgTypes),
2527 staticArgsValues, bootstrapName, name, false);
2528
2529 Type receiverType = tree.sym.type.isPrimitiveReferenceType() ? tree.sym.type.asValueType() : tree.sym.type;
2530 VarSymbol _this = new VarSymbol(SYNTHETIC, names._this, receiverType, tree.sym);
2531
2532 JCMethodInvocation proxyCall;
2533 if (!isEquals) {
2534 proxyCall = make.Apply(List.nil(), qualifier, List.of(make.Ident(_this)));
2535 } else {
2536 VarSymbol o = msym.params.head;
2537 o.adr = 0;
2538 proxyCall = make.Apply(List.nil(), qualifier, List.of(make.Ident(_this), make.Ident(o)));
2539 }
2540 proxyCall.type = qualifier.type;
2541 return make.MethodDef(msym, make.Block(0, List.of(make.Return(proxyCall))));
2542 } else {
2543 return make.Block(SYNTHETIC, List.nil());
2544 }
2545 }
2546
2547 private String argsTypeSig(List<Type> typeList) {
2548 LowerSignatureGenerator sg = new LowerSignatureGenerator();
2549 sg.assembleSig(typeList);
2550 return sg.toString();
2551 }
2552
2553 /**
2554 * Signature Generation
2555 */
2556 private class LowerSignatureGenerator extends Types.SignatureGenerator {
2557
2558 /**
2559 * An output buffer for type signatures.
2560 */
2561 StringBuilder sb = new StringBuilder();
2562
2563 LowerSignatureGenerator() {
2564 super(types);
2565 }
2566
2567 @Override
2568 protected void append(char ch) {
2569 sb.append(ch);
2570 }
2571
2572 @Override
2573 protected void append(byte[] ba) {
2574 sb.append(new String(ba));
2575 }
2576
2577 @Override
2578 protected void append(Name name) {
2579 sb.append(name.toString());
2580 }
2581
2582 @Override
2583 public String toString() {
2584 return sb.toString();
2585 }
2586 }
2587
2588 /**
2589 * Creates an indy qualifier, helpful to be part of an indy invocation
2590 * @param site the site
2591 * @param tree a class declaration tree
2592 * @param msym the method symbol
2593 * @param staticArgTypes the static argument types
2594 * @param staticArgValues the static argument values
2595 * @param bootstrapName the bootstrap name to look for
2596 * @param argName normally bootstraps receives a method name as second argument, if you want that name
2597 * to be different to that of the bootstrap name pass a different name here
2598 * @param isStatic is it static or not
2599 * @return a field access tree
2600 */
2601 JCFieldAccess makeIndyQualifier(
2602 Type site,
2603 JCClassDecl tree,
2604 MethodSymbol msym,
2605 List<Type> staticArgTypes,
2606 LoadableConstant[] staticArgValues,
2607 Name bootstrapName,
2608 Name argName,
2609 boolean isStatic) {
2610 Symbol bsm = rs.resolveInternalMethod(tree.pos(), attrEnv, site,
2611 bootstrapName, staticArgTypes, List.nil());
2612
2613 MethodType indyType = msym.type.asMethodType();
2614 Type receiverType = tree.sym.type.isPrimitiveReferenceType() ? tree.sym.type.asValueType() : tree.sym.type;
2615 indyType = new MethodType(
2616 isStatic ? List.nil() : indyType.argtypes.prepend(receiverType),
2617 indyType.restype,
2618 indyType.thrown,
2619 syms.methodClass
2620 );
2621 DynamicMethodSymbol dynSym = new DynamicMethodSymbol(argName,
2622 syms.noSymbol,
2623 ((MethodSymbol)bsm).asHandle(),
2624 indyType,
2625 staticArgValues);
2626 JCFieldAccess qualifier = make.Select(make.QualIdent(site.tsym), argName);
2627 qualifier.sym = dynSym;
2628 qualifier.type = msym.type.asMethodType().restype;
2629 return qualifier;
2630 }
2631
2632 public void visitMethodDef(JCMethodDecl tree) {
2633 if (tree.name == names.init && (currentClass.flags_field&ENUM) != 0) {
2634 // Add "String $enum$name, int $enum$ordinal" to the beginning of the
2635 // argument list for each constructor of an enum.
2636 JCVariableDecl nameParam = make_at(tree.pos()).
2637 Param(names.fromString(target.syntheticNameChar() +
2638 "enum" + target.syntheticNameChar() + "name"),
2639 syms.stringType, tree.sym);
2640 nameParam.mods.flags |= SYNTHETIC; nameParam.sym.flags_field |= SYNTHETIC;
2641 JCVariableDecl ordParam = make.
2642 Param(names.fromString(target.syntheticNameChar() +
2643 "enum" + target.syntheticNameChar() +
2644 "ordinal"),
2645 syms.intType, tree.sym);
2646 ordParam.mods.flags |= SYNTHETIC; ordParam.sym.flags_field |= SYNTHETIC;
2647
2648 MethodSymbol m = tree.sym;
2649 tree.params = tree.params.prepend(ordParam).prepend(nameParam);
2650
2651 m.extraParams = m.extraParams.prepend(ordParam.sym);
2652 m.extraParams = m.extraParams.prepend(nameParam.sym);
2653 Type olderasure = m.erasure(types);
2654 m.erasure_field = new MethodType(
2655 olderasure.getParameterTypes().prepend(syms.intType).prepend(syms.stringType),
2656 olderasure.getReturnType(),
2657 olderasure.getThrownTypes(),
2658 syms.methodClass);
2659 }
2660
2661 JCMethodDecl prevMethodDef = currentMethodDef;
2662 MethodSymbol prevMethodSym = currentMethodSym;
2663 try {
2664 currentMethodDef = tree;
2665 currentMethodSym = tree.sym;
2666 visitMethodDefInternal(tree);
2667 } finally {
2668 currentMethodDef = prevMethodDef;
2669 currentMethodSym = prevMethodSym;
2670 }
2671 }
2672
2673 private void visitMethodDefInternal(JCMethodDecl tree) {
2674 if (tree.name == names.init &&
2675 (currentClass.isInner() || currentClass.isDirectlyOrIndirectlyLocal())) {
2676 // We are seeing a constructor of an inner class.
2677 MethodSymbol m = tree.sym;
2678
2679 // Push a new proxy scope for constructor parameters.
2680 // and create definitions for any this$n and proxy parameters.
2681 Map<Symbol, Symbol> prevProxies = proxies;
2682 proxies = new HashMap<>(proxies);
2683 List<VarSymbol> prevOuterThisStack = outerThisStack;
2684 List<VarSymbol> fvs = freevars(currentClass);
2685 JCVariableDecl otdef = null;
2686 if (currentClass.hasOuterInstance())
2687 otdef = outerThisDef(tree.pos, m);
2688 List<JCVariableDecl> fvdefs = freevarDefs(tree.pos, fvs, m, PARAMETER);
2689
2690 // Recursively translate result type, parameters and thrown list.
2691 tree.restype = translate(tree.restype);
2692 tree.params = translateVarDefs(tree.params);
2693 tree.thrown = translate(tree.thrown);
2694
2695 // when compiling stubs, don't process body
2696 if (tree.body == null) {
2697 result = tree;
2698 return;
2699 }
2700
2701 // Add this$n (if needed) in front of and free variables behind
2702 // constructor parameter list.
2703 tree.params = tree.params.appendList(fvdefs);
2704 if (currentClass.hasOuterInstance()) {
2705 tree.params = tree.params.prepend(otdef);
2706 }
2707
2708 // If this is an initial constructor, i.e., it does not start with
2709 // this(...), insert initializers for this$n and proxies
2710 // before (pre-1.4, after) the call to superclass constructor.
2711 JCStatement selfCall = translate(tree.body.stats.head);
2712
2713 List<JCStatement> added = List.nil();
2714 if (fvs.nonEmpty()) {
2715 List<Type> addedargtypes = List.nil();
2716 for (List<VarSymbol> l = fvs; l.nonEmpty(); l = l.tail) {
2717 m.capturedLocals =
2718 m.capturedLocals.prepend((VarSymbol)
2719 (proxies.get(l.head)));
2720 if (TreeInfo.isInitialConstructor(tree)) {
2721 added = added.prepend(
2722 initField(tree.body.pos, proxies.get(l.head), prevProxies.get(l.head)));
2723 }
2724 addedargtypes = addedargtypes.prepend(l.head.erasure(types));
2725 }
2726 Type olderasure = m.erasure(types);
2727 m.erasure_field = new MethodType(
2728 olderasure.getParameterTypes().appendList(addedargtypes),
2729 olderasure.getReturnType(),
2730 olderasure.getThrownTypes(),
2731 syms.methodClass);
2732 }
2733 if (currentClass.hasOuterInstance() &&
2734 TreeInfo.isInitialConstructor(tree))
2735 {
2736 added = added.prepend(initOuterThis(tree.body.pos));
2737 }
2738
2739 // pop local variables from proxy stack
2740 proxies = prevProxies;
2741
2742 // recursively translate following local statements and
2743 // combine with this- or super-call
2744 List<JCStatement> stats = translate(tree.body.stats.tail);
2745 tree.body.stats = stats.prepend(selfCall).prependList(added);
2746 outerThisStack = prevOuterThisStack;
2747 } else {
2748 Map<Symbol, Symbol> prevLambdaTranslationMap =
2749 lambdaTranslationMap;
2750 try {
2751 lambdaTranslationMap = (tree.sym.flags() & SYNTHETIC) != 0 &&
2752 tree.sym.name.startsWith(names.lambda) ?
2753 makeTranslationMap(tree) : null;
2754 super.visitMethodDef(tree);
2755 } finally {
2756 lambdaTranslationMap = prevLambdaTranslationMap;
2757 }
2758 }
2759 if (tree.name == names.init && (tree.sym.flags_field & Flags.COMPACT_RECORD_CONSTRUCTOR) != 0) {
2760 // lets find out if there is any field waiting to be initialized
2761 ListBuffer<VarSymbol> fields = new ListBuffer<>();
2762 for (Symbol sym : currentClass.getEnclosedElements()) {
2763 if (sym.kind == Kinds.Kind.VAR && ((sym.flags() & RECORD) != 0))
2764 fields.append((VarSymbol) sym);
2765 }
2766 for (VarSymbol field: fields) {
2767 if ((field.flags_field & Flags.UNINITIALIZED_FIELD) != 0) {
2768 VarSymbol param = tree.params.stream().filter(p -> p.name == field.name).findFirst().get().sym;
2769 make.at(tree.pos);
2770 tree.body.stats = tree.body.stats.append(
2771 make.Exec(
2772 make.Assign(
2773 make.Select(make.This(field.owner.erasure(types)), field),
2774 make.Ident(param)).setType(field.erasure(types))));
2775 // we don't need the flag at the field anymore
2776 field.flags_field &= ~Flags.UNINITIALIZED_FIELD;
2777 }
2778 }
2779 }
2780 result = tree;
2781 }
2782 //where
2783 private Map<Symbol, Symbol> makeTranslationMap(JCMethodDecl tree) {
2784 Map<Symbol, Symbol> translationMap = new HashMap<>();
2785 for (JCVariableDecl vd : tree.params) {
2786 Symbol p = vd.sym;
2787 if (p != p.baseSymbol()) {
2788 translationMap.put(p.baseSymbol(), p);
2789 }
2790 }
2791 return translationMap;
2792 }
2793
2794 public void visitTypeCast(JCTypeCast tree) {
2795 tree.clazz = translate(tree.clazz);
2796 if (tree.type.isPrimitive() != tree.expr.type.isPrimitive())
2797 tree.expr = translate(tree.expr, tree.type);
2798 else
2799 tree.expr = translate(tree.expr);
2800 result = tree;
2801 }
2802
2803 public void visitNewClass(JCNewClass tree) {
2804 ClassSymbol c = (ClassSymbol)tree.constructor.owner;
2805
2806 // Box arguments, if necessary
2807 boolean isEnum = (tree.constructor.owner.flags() & ENUM) != 0;
2808 List<Type> argTypes = tree.constructor.type.getParameterTypes();
2809 if (isEnum) argTypes = argTypes.prepend(syms.intType).prepend(syms.stringType);
2810 tree.args = boxArgs(argTypes, tree.args, tree.varargsElement);
2811 tree.varargsElement = null;
2812
2813 // If created class is local, add free variables after
2814 // explicit constructor arguments.
2815 if (c.isDirectlyOrIndirectlyLocal()) {
2816 tree.args = tree.args.appendList(loadFreevars(tree.pos(), freevars(c)));
2817 }
2818
2819 // If an access constructor is used, append null as a last argument.
2820 Symbol constructor = accessConstructor(tree.pos(), tree.constructor);
2821 if (constructor != tree.constructor) {
2822 tree.args = tree.args.append(makeNull());
2823 tree.constructor = constructor;
2824 }
2825
2826 // If created class has an outer instance, and new is qualified, pass
2827 // qualifier as first argument. If new is not qualified, pass the
2828 // correct outer instance as first argument.
2829 if (c.hasOuterInstance()) {
2830 JCExpression thisArg;
2831 if (tree.encl != null) {
2832 thisArg = attr.makeNullCheck(translate(tree.encl));
2833 thisArg.type = tree.encl.type;
2834 } else if (c.isDirectlyOrIndirectlyLocal()) {
2835 // local class
2836 thisArg = makeThis(tree.pos(), c.type.getEnclosingType().tsym);
2837 } else {
2838 // nested class
2839 thisArg = makeOwnerThis(tree.pos(), c, false);
2840 }
2841 tree.args = tree.args.prepend(thisArg);
2842 }
2843 tree.encl = null;
2844
2845 // If we have an anonymous class, create its flat version, rather
2846 // than the class or interface following new.
2847 if (tree.def != null) {
2848 Map<Symbol, Symbol> prevLambdaTranslationMap = lambdaTranslationMap;
2849 try {
2850 lambdaTranslationMap = null;
2851 translate(tree.def);
2852 } finally {
2853 lambdaTranslationMap = prevLambdaTranslationMap;
2854 }
2855
2856 tree.clazz = access(make_at(tree.clazz.pos()).Ident(tree.def.sym));
2857 tree.def = null;
2858 } else {
2859 tree.clazz = access(c, tree.clazz, enclOp, false);
2860 }
2861 if (tree.clazz.type.tsym == syms.objectType.tsym) {
2862 Assert.check(tree.def == null && tree.encl == null);
2863 result = makeCall(make.Ident(syms.objectsType.tsym), names.newIdentity, List.nil());
2864 } else {
2865 result = tree;
2866 }
2867 }
2868
2869 // Simplify conditionals with known constant controlling expressions.
2870 // This allows us to avoid generating supporting declarations for
2871 // the dead code, which will not be eliminated during code generation.
2872 // Note that Flow.isFalse and Flow.isTrue only return true
2873 // for constant expressions in the sense of JLS 15.27, which
2874 // are guaranteed to have no side-effects. More aggressive
2875 // constant propagation would require that we take care to
2876 // preserve possible side-effects in the condition expression.
2877
2878 // One common case is equality expressions involving a constant and null.
2879 // Since null is not a constant expression (because null cannot be
2880 // represented in the constant pool), equality checks involving null are
2881 // not captured by Flow.isTrue/isFalse.
2882 // Equality checks involving a constant and null, e.g.
2883 // "" == null
2884 // are safe to simplify as no side-effects can occur.
2885
2886 private boolean isTrue(JCTree exp) {
2887 if (exp.type.isTrue())
2888 return true;
2889 Boolean b = expValue(exp);
2890 return b == null ? false : b;
2891 }
2892 private boolean isFalse(JCTree exp) {
2893 if (exp.type.isFalse())
2894 return true;
2895 Boolean b = expValue(exp);
2896 return b == null ? false : !b;
2897 }
2898 /* look for (in)equality relations involving null.
2899 * return true - if expression is always true
2900 * false - if expression is always false
2901 * null - if expression cannot be eliminated
2902 */
2903 private Boolean expValue(JCTree exp) {
2904 while (exp.hasTag(PARENS))
2905 exp = ((JCParens)exp).expr;
2906
2907 boolean eq;
2908 switch (exp.getTag()) {
2909 case EQ: eq = true; break;
2910 case NE: eq = false; break;
2911 default:
2912 return null;
2913 }
2914
2915 // we have a JCBinary(EQ|NE)
2916 // check if we have two literals (constants or null)
2917 JCBinary b = (JCBinary)exp;
2918 if (b.lhs.type.hasTag(BOT)) return expValueIsNull(eq, b.rhs);
2919 if (b.rhs.type.hasTag(BOT)) return expValueIsNull(eq, b.lhs);
2920 return null;
2921 }
2922 private Boolean expValueIsNull(boolean eq, JCTree t) {
2923 if (t.type.hasTag(BOT)) return Boolean.valueOf(eq);
2924 if (t.hasTag(LITERAL)) return Boolean.valueOf(!eq);
2925 return null;
2926 }
2927
2928 /** Visitor method for conditional expressions.
2929 */
2930 @Override
2931 public void visitConditional(JCConditional tree) {
2932 JCTree cond = tree.cond = translate(tree.cond, syms.booleanType);
2933 if (isTrue(cond)) {
2934 result = convert(translate(tree.truepart, tree.type), tree.type);
2935 addPrunedInfo(cond);
2936 } else if (isFalse(cond)) {
2937 result = convert(translate(tree.falsepart, tree.type), tree.type);
2938 addPrunedInfo(cond);
2939 } else {
2940 // Condition is not a compile-time constant.
2941 tree.truepart = translate(tree.truepart, tree.type);
2942 tree.falsepart = translate(tree.falsepart, tree.type);
2943 result = tree;
2944 }
2945 }
2946 //where
2947 private JCExpression convert(JCExpression tree, Type pt) {
2948 if (tree.type == pt || tree.type.hasTag(BOT))
2949 return tree;
2950 JCExpression result = make_at(tree.pos()).TypeCast(make.Type(pt), tree);
2951 result.type = (tree.type.constValue() != null) ? cfolder.coerce(tree.type, pt)
2952 : pt;
2953 return result;
2954 }
2955
2956 /** Visitor method for if statements.
2957 */
2958 public void visitIf(JCIf tree) {
2959 JCTree cond = tree.cond = translate(tree.cond, syms.booleanType);
2960 if (isTrue(cond)) {
2961 result = translate(tree.thenpart);
2962 addPrunedInfo(cond);
2963 } else if (isFalse(cond)) {
2964 if (tree.elsepart != null) {
2965 result = translate(tree.elsepart);
2966 } else {
2967 result = make.Skip();
2968 }
2969 addPrunedInfo(cond);
2970 } else {
2971 // Condition is not a compile-time constant.
2972 tree.thenpart = translate(tree.thenpart);
2973 tree.elsepart = translate(tree.elsepart);
2974 result = tree;
2975 }
2976 }
2977
2978 /** Visitor method for assert statements. Translate them away.
2979 */
2980 public void visitAssert(JCAssert tree) {
2981 tree.cond = translate(tree.cond, syms.booleanType);
2982 if (!tree.cond.type.isTrue()) {
2983 JCExpression cond = assertFlagTest(tree.pos());
2984 List<JCExpression> exnArgs = (tree.detail == null) ?
2985 List.nil() : List.of(translate(tree.detail));
2986 if (!tree.cond.type.isFalse()) {
2987 cond = makeBinary
2988 (AND,
2989 cond,
2990 makeUnary(NOT, tree.cond));
2991 }
2992 result =
2993 make.If(cond,
2994 make_at(tree).
2995 Throw(makeNewClass(syms.assertionErrorType, exnArgs)),
2996 null);
2997 } else {
2998 result = make.Skip();
2999 }
3000 }
3001
3002 public void visitApply(JCMethodInvocation tree) {
3003 Symbol meth = TreeInfo.symbol(tree.meth);
3004 List<Type> argtypes = meth.type.getParameterTypes();
3005 if (meth.name == names.init && meth.owner == syms.enumSym)
3006 argtypes = argtypes.tail.tail;
3007 tree.args = boxArgs(argtypes, tree.args, tree.varargsElement);
3008 tree.varargsElement = null;
3009 Name methName = TreeInfo.name(tree.meth);
3010 if (meth.name==names.init) {
3011 // We are seeing a this(...) or super(...) constructor call.
3012 // If an access constructor is used, append null as a last argument.
3013 Symbol constructor = accessConstructor(tree.pos(), meth);
3014 if (constructor != meth) {
3015 tree.args = tree.args.append(makeNull());
3016 TreeInfo.setSymbol(tree.meth, constructor);
3017 }
3018
3019 // If we are calling a constructor of a local class, add
3020 // free variables after explicit constructor arguments.
3021 ClassSymbol c = (ClassSymbol)constructor.owner;
3022 if (c.isDirectlyOrIndirectlyLocal()) {
3023 tree.args = tree.args.appendList(loadFreevars(tree.pos(), freevars(c)));
3024 }
3025
3026 // If we are calling a constructor of an enum class, pass
3027 // along the name and ordinal arguments
3028 if ((c.flags_field&ENUM) != 0 || c.getQualifiedName() == names.java_lang_Enum) {
3029 List<JCVariableDecl> params = currentMethodDef.params;
3030 if (currentMethodSym.owner.hasOuterInstance())
3031 params = params.tail; // drop this$n
3032 tree.args = tree.args
3033 .prepend(make_at(tree.pos()).Ident(params.tail.head.sym)) // ordinal
3034 .prepend(make.Ident(params.head.sym)); // name
3035 }
3036
3037 // If we are calling a constructor of a class with an outer
3038 // instance, and the call
3039 // is qualified, pass qualifier as first argument in front of
3040 // the explicit constructor arguments. If the call
3041 // is not qualified, pass the correct outer instance as
3042 // first argument.
3043 if (c.hasOuterInstance()) {
3044 JCExpression thisArg;
3045 if (tree.meth.hasTag(SELECT)) {
3046 thisArg = attr.
3047 makeNullCheck(translate(((JCFieldAccess) tree.meth).selected));
3048 tree.meth = make.Ident(constructor);
3049 ((JCIdent) tree.meth).name = methName;
3050 } else if (c.isDirectlyOrIndirectlyLocal() || methName == names._this){
3051 // local class or this() call
3052 thisArg = makeThis(tree.meth.pos(), c.type.getEnclosingType().tsym);
3053 } else {
3054 // super() call of nested class - never pick 'this'
3055 thisArg = makeOwnerThisN(tree.meth.pos(), c, false);
3056 }
3057 tree.args = tree.args.prepend(thisArg);
3058 }
3059 } else {
3060 // We are seeing a normal method invocation; translate this as usual.
3061 tree.meth = translate(tree.meth);
3062
3063 // If the translated method itself is an Apply tree, we are
3064 // seeing an access method invocation. In this case, append
3065 // the method arguments to the arguments of the access method.
3066 if (tree.meth.hasTag(APPLY)) {
3067 JCMethodInvocation app = (JCMethodInvocation)tree.meth;
3068 app.args = tree.args.prependList(app.args);
3069 result = app;
3070 return;
3071 }
3072 }
3073 result = tree;
3074 }
3075
3076 List<JCExpression> boxArgs(List<Type> parameters, List<JCExpression> _args, Type varargsElement) {
3077 List<JCExpression> args = _args;
3078 if (parameters.isEmpty()) return args;
3079 boolean anyChanges = false;
3080 ListBuffer<JCExpression> result = new ListBuffer<>();
3081 while (parameters.tail.nonEmpty()) {
3082 JCExpression arg = translate(args.head, parameters.head);
3083 anyChanges |= (arg != args.head);
3084 result.append(arg);
3085 args = args.tail;
3086 parameters = parameters.tail;
3087 }
3088 Type parameter = parameters.head;
3089 if (varargsElement != null) {
3090 anyChanges = true;
3091 ListBuffer<JCExpression> elems = new ListBuffer<>();
3092 while (args.nonEmpty()) {
3093 JCExpression arg = translate(args.head, varargsElement);
3094 elems.append(arg);
3095 args = args.tail;
3096 }
3097 JCNewArray boxedArgs = make.NewArray(make.Type(varargsElement),
3098 List.nil(),
3099 elems.toList());
3100 boxedArgs.type = new ArrayType(varargsElement, syms.arrayClass);
3101 result.append(boxedArgs);
3102 } else {
3103 if (args.length() != 1) throw new AssertionError(args);
3104 JCExpression arg = translate(args.head, parameter);
3105 anyChanges |= (arg != args.head);
3106 result.append(arg);
3107 if (!anyChanges) return _args;
3108 }
3109 return result.toList();
3110 }
3111
3112 /** Apply primitive value/reference conversions as needed */
3113 @SuppressWarnings("unchecked")
3114 <T extends JCExpression> T applyPrimitiveConversionsAsNeeded(T tree, Type type) {
3115 boolean haveValue = tree.type.isPrimitiveClass();
3116 if (haveValue == type.isPrimitiveClass())
3117 return tree;
3118 // For narrowing conversion, insert a cast which should trigger a null check
3119 // For widening conversions, insert a cast if emitting a unified class file.
3120 return (T) make.TypeCast(type, tree);
3121
3122 }
3123
3124
3125
3126 /** Expand a boxing or unboxing conversion if needed. */
3127 @SuppressWarnings("unchecked") // XXX unchecked
3128 <T extends JCExpression> T boxIfNeeded(T tree, Type type) {
3129 boolean havePrimitive = tree.type.isPrimitive();
3130 if (havePrimitive == type.isPrimitive())
3131 return tree;
3132 if (havePrimitive) {
3133 Type unboxedTarget = types.unboxedType(type);
3134 if (!unboxedTarget.hasTag(NONE)) {
3135 if (!types.isSubtype(tree.type, unboxedTarget)) //e.g. Character c = 89;
3136 tree.type = unboxedTarget.constType(tree.type.constValue());
3137 return (T)boxPrimitive(tree, types.erasure(type));
3138 } else {
3139 tree = (T)boxPrimitive(tree);
3140 }
3141 } else {
3142 tree = (T)unbox(tree, type);
3143 }
3144 return tree;
3145 }
3146
3147 /** Box up a single primitive expression. */
3148 JCExpression boxPrimitive(JCExpression tree) {
3149 return boxPrimitive(tree, types.boxedClass(tree.type).type);
3150 }
3151
3152 /** Box up a single primitive expression. */
3153 JCExpression boxPrimitive(JCExpression tree, Type box) {
3154 make_at(tree.pos());
3155 Symbol valueOfSym = lookupMethod(tree.pos(),
3156 names.valueOf,
3157 box,
3158 List.<Type>nil()
3159 .prepend(tree.type));
3160 return make.App(make.QualIdent(valueOfSym), List.of(tree));
3161 }
3162
3163 /** Unbox an object to a primitive value. */
3164 JCExpression unbox(JCExpression tree, Type primitive) {
3165 Type unboxedType = types.unboxedType(tree.type);
3166 if (unboxedType.hasTag(NONE)) {
3167 unboxedType = primitive;
3168 if (!unboxedType.isPrimitive())
3169 throw new AssertionError(unboxedType);
3170 make_at(tree.pos());
3171 tree = make.TypeCast(types.boxedClass(unboxedType).type, tree);
3172 } else {
3173 // There must be a conversion from unboxedType to primitive.
3174 if (!types.isSubtype(unboxedType, primitive))
3175 throw new AssertionError(tree);
3176 }
3177 make_at(tree.pos());
3178 Symbol valueSym = lookupMethod(tree.pos(),
3179 unboxedType.tsym.name.append(names.Value), // x.intValue()
3180 tree.type,
3181 List.nil());
3182 return make.App(make.Select(tree, valueSym));
3183 }
3184
3185 /** Visitor method for parenthesized expressions.
3186 * If the subexpression has changed, omit the parens.
3187 */
3188 public void visitParens(JCParens tree) {
3189 JCTree expr = translate(tree.expr);
3190 result = ((expr == tree.expr) ? tree : expr);
3191 }
3192
3193 public void visitIndexed(JCArrayAccess tree) {
3194 tree.indexed = translate(tree.indexed);
3195 tree.index = translate(tree.index, syms.intType);
3196 result = tree;
3197 }
3198
3199 public void visitAssign(JCAssign tree) {
3200 tree.lhs = translate(tree.lhs, tree);
3201 tree.rhs = translate(tree.rhs, tree.lhs.type);
3202
3203 // If translated left hand side is an Apply, we are
3204 // seeing an access method invocation. In this case, append
3205 // right hand side as last argument of the access method.
3206 if (tree.lhs.hasTag(APPLY)) {
3207 JCMethodInvocation app = (JCMethodInvocation)tree.lhs;
3208 app.args = List.of(tree.rhs).prependList(app.args);
3209 result = app;
3210 } else {
3211 result = tree;
3212 }
3213 }
3214
3215 public void visitAssignop(final JCAssignOp tree) {
3216 final boolean boxingReq = !tree.lhs.type.isPrimitive() &&
3217 tree.operator.type.getReturnType().isPrimitive();
3218
3219 AssignopDependencyScanner depScanner = new AssignopDependencyScanner(tree);
3220 depScanner.scan(tree.rhs);
3221
3222 if (boxingReq || depScanner.dependencyFound) {
3223 // boxing required; need to rewrite as x = (unbox typeof x)(x op y);
3224 // or if x == (typeof x)z then z = (unbox typeof x)((typeof x)z op y)
3225 // (but without recomputing x)
3226 JCTree newTree = abstractLval(tree.lhs, lhs -> {
3227 Tag newTag = tree.getTag().noAssignOp();
3228 // Erasure (TransTypes) can change the type of
3229 // tree.lhs. However, we can still get the
3230 // unerased type of tree.lhs as it is stored
3231 // in tree.type in Attr.
3232 OperatorSymbol newOperator = operators.resolveBinary(tree,
3233 newTag,
3234 tree.type,
3235 tree.rhs.type);
3236 //Need to use the "lhs" at two places, once on the future left hand side
3237 //and once in the future binary operator. But further processing may change
3238 //the components of the tree in place (see visitSelect for e.g. <Class>.super.<ident>),
3239 //so cloning the tree to avoid interference between the uses:
3240 JCExpression expr = (JCExpression) lhs.clone();
3241 if (expr.type != tree.type)
3242 expr = make.TypeCast(tree.type, expr);
3243 JCBinary opResult = make.Binary(newTag, expr, tree.rhs);
3244 opResult.operator = newOperator;
3245 opResult.type = newOperator.type.getReturnType();
3246 JCExpression newRhs = boxingReq ?
3247 make.TypeCast(types.unboxedType(tree.type), opResult) :
3248 opResult;
3249 return make.Assign(lhs, newRhs).setType(tree.type);
3250 });
3251 result = translate(newTree);
3252 return;
3253 }
3254 tree.lhs = translate(tree.lhs, tree);
3255 tree.rhs = translate(tree.rhs, tree.operator.type.getParameterTypes().tail.head);
3256
3257 // If translated left hand side is an Apply, we are
3258 // seeing an access method invocation. In this case, append
3259 // right hand side as last argument of the access method.
3260 if (tree.lhs.hasTag(APPLY)) {
3261 JCMethodInvocation app = (JCMethodInvocation)tree.lhs;
3262 // if operation is a += on strings,
3263 // make sure to convert argument to string
3264 JCExpression rhs = tree.operator.opcode == string_add
3265 ? makeString(tree.rhs)
3266 : tree.rhs;
3267 app.args = List.of(rhs).prependList(app.args);
3268 result = app;
3269 } else {
3270 result = tree;
3271 }
3272 }
3273
3274 class AssignopDependencyScanner extends TreeScanner {
3275
3276 Symbol sym;
3277 boolean dependencyFound = false;
3278
3279 AssignopDependencyScanner(JCAssignOp tree) {
3280 this.sym = TreeInfo.symbol(tree.lhs);
3281 }
3282
3283 @Override
3284 public void scan(JCTree tree) {
3285 if (tree != null && sym != null) {
3286 tree.accept(this);
3287 }
3288 }
3289
3290 @Override
3291 public void visitAssignop(JCAssignOp tree) {
3292 if (TreeInfo.symbol(tree.lhs) == sym) {
3293 dependencyFound = true;
3294 return;
3295 }
3296 super.visitAssignop(tree);
3297 }
3298
3299 @Override
3300 public void visitUnary(JCUnary tree) {
3301 if (TreeInfo.symbol(tree.arg) == sym) {
3302 dependencyFound = true;
3303 return;
3304 }
3305 super.visitUnary(tree);
3306 }
3307 }
3308
3309 /** Lower a tree of the form e++ or e-- where e is an object type */
3310 JCExpression lowerBoxedPostop(final JCUnary tree) {
3311 // translate to tmp1=lval(e); tmp2=tmp1; tmp1 OP 1; tmp2
3312 // or
3313 // translate to tmp1=lval(e); tmp2=tmp1; (typeof tree)tmp1 OP 1; tmp2
3314 // where OP is += or -=
3315 final boolean cast = TreeInfo.skipParens(tree.arg).hasTag(TYPECAST);
3316 return abstractLval(tree.arg, tmp1 -> abstractRval(tmp1, tree.arg.type, tmp2 -> {
3317 Tag opcode = (tree.hasTag(POSTINC))
3318 ? PLUS_ASG : MINUS_ASG;
3319 //"tmp1" and "tmp2" may refer to the same instance
3320 //(for e.g. <Class>.super.<ident>). But further processing may
3321 //change the components of the tree in place (see visitSelect),
3322 //so cloning the tree to avoid interference between the two uses:
3323 JCExpression lhs = (JCExpression)tmp1.clone();
3324 lhs = cast
3325 ? make.TypeCast(tree.arg.type, lhs)
3326 : lhs;
3327 JCExpression update = makeAssignop(opcode,
3328 lhs,
3329 make.Literal(1));
3330 return makeComma(update, tmp2);
3331 }));
3332 }
3333
3334 public void visitUnary(JCUnary tree) {
3335 boolean isUpdateOperator = tree.getTag().isIncOrDecUnaryOp();
3336 if (isUpdateOperator && !tree.arg.type.isPrimitive()) {
3337 switch(tree.getTag()) {
3338 case PREINC: // ++ e
3339 // translate to e += 1
3340 case PREDEC: // -- e
3341 // translate to e -= 1
3342 {
3343 JCTree.Tag opcode = (tree.hasTag(PREINC))
3344 ? PLUS_ASG : MINUS_ASG;
3345 JCAssignOp newTree = makeAssignop(opcode,
3346 tree.arg,
3347 make.Literal(1));
3348 result = translate(newTree, tree.type);
3349 return;
3350 }
3351 case POSTINC: // e ++
3352 case POSTDEC: // e --
3353 {
3354 result = translate(lowerBoxedPostop(tree), tree.type);
3355 return;
3356 }
3357 }
3358 throw new AssertionError(tree);
3359 }
3360
3361 tree.arg = boxIfNeeded(translate(tree.arg, tree), tree.type);
3362
3363 if (tree.hasTag(NOT) && tree.arg.type.constValue() != null) {
3364 tree.type = cfolder.fold1(bool_not, tree.arg.type);
3365 }
3366
3367 // If translated left hand side is an Apply, we are
3368 // seeing an access method invocation. In this case, return
3369 // that access method invocation as result.
3370 if (isUpdateOperator && tree.arg.hasTag(APPLY)) {
3371 result = tree.arg;
3372 } else {
3373 result = tree;
3374 }
3375 }
3376
3377 public void visitBinary(JCBinary tree) {
3378 List<Type> formals = tree.operator.type.getParameterTypes();
3379 JCTree lhs = tree.lhs = translate(tree.lhs, formals.head);
3380 switch (tree.getTag()) {
3381 case OR:
3382 if (isTrue(lhs)) {
3383 result = lhs;
3384 return;
3385 }
3386 if (isFalse(lhs)) {
3387 result = translate(tree.rhs, formals.tail.head);
3388 return;
3389 }
3390 break;
3391 case AND:
3392 if (isFalse(lhs)) {
3393 result = lhs;
3394 return;
3395 }
3396 if (isTrue(lhs)) {
3397 result = translate(tree.rhs, formals.tail.head);
3398 return;
3399 }
3400 break;
3401 }
3402 tree.rhs = translate(tree.rhs, formals.tail.head);
3403 result = tree;
3404 }
3405
3406 public void visitIdent(JCIdent tree) {
3407 result = access(tree.sym, tree, enclOp, false);
3408 }
3409
3410 /** Translate away the foreach loop. */
3411 public void visitForeachLoop(JCEnhancedForLoop tree) {
3412 if (types.elemtype(tree.expr.type) == null)
3413 visitIterableForeachLoop(tree);
3414 else
3415 visitArrayForeachLoop(tree);
3416 }
3417 // where
3418 /**
3419 * A statement of the form
3420 *
3421 * <pre>
3422 * for ( T v : arrayexpr ) stmt;
3423 * </pre>
3424 *
3425 * (where arrayexpr is of an array type) gets translated to
3426 *
3427 * <pre>{@code
3428 * for ( { arraytype #arr = arrayexpr;
3429 * int #len = array.length;
3430 * int #i = 0; };
3431 * #i < #len; i$++ ) {
3432 * T v = arr$[#i];
3433 * stmt;
3434 * }
3435 * }</pre>
3436 *
3437 * where #arr, #len, and #i are freshly named synthetic local variables.
3438 */
3439 private void visitArrayForeachLoop(JCEnhancedForLoop tree) {
3440 make_at(tree.expr.pos());
3441 VarSymbol arraycache = new VarSymbol(SYNTHETIC,
3442 names.fromString("arr" + target.syntheticNameChar()),
3443 tree.expr.type,
3444 currentMethodSym);
3445 JCStatement arraycachedef = make.VarDef(arraycache, tree.expr);
3446 VarSymbol lencache = new VarSymbol(SYNTHETIC,
3447 names.fromString("len" + target.syntheticNameChar()),
3448 syms.intType,
3449 currentMethodSym);
3450 JCStatement lencachedef = make.
3451 VarDef(lencache, make.Select(make.Ident(arraycache), syms.lengthVar));
3452 VarSymbol index = new VarSymbol(SYNTHETIC,
3453 names.fromString("i" + target.syntheticNameChar()),
3454 syms.intType,
3455 currentMethodSym);
3456
3457 JCVariableDecl indexdef = make.VarDef(index, make.Literal(INT, 0));
3458 indexdef.init.type = indexdef.type = syms.intType.constType(0);
3459
3460 List<JCStatement> loopinit = List.of(arraycachedef, lencachedef, indexdef);
3461 JCBinary cond = makeBinary(LT, make.Ident(index), make.Ident(lencache));
3462
3463 JCExpressionStatement step = make.Exec(makeUnary(PREINC, make.Ident(index)));
3464
3465 Type elemtype = types.elemtype(tree.expr.type);
3466 JCExpression loopvarinit = make.Indexed(make.Ident(arraycache),
3467 make.Ident(index)).setType(elemtype);
3468 JCVariableDecl loopvardef = (JCVariableDecl)make.VarDef(tree.var.mods,
3469 tree.var.name,
3470 tree.var.vartype,
3471 loopvarinit).setType(tree.var.type);
3472 loopvardef.sym = tree.var.sym;
3473 JCBlock body = make.
3474 Block(0, List.of(loopvardef, tree.body));
3475
3476 result = translate(make.
3477 ForLoop(loopinit,
3478 cond,
3479 List.of(step),
3480 body));
3481 patchTargets(body, tree, result);
3482 }
3483 /** Patch up break and continue targets. */
3484 private void patchTargets(JCTree body, final JCTree src, final JCTree dest) {
3485 class Patcher extends TreeScanner {
3486 public void visitBreak(JCBreak tree) {
3487 if (tree.target == src)
3488 tree.target = dest;
3489 }
3490 public void visitYield(JCYield tree) {
3491 if (tree.target == src)
3492 tree.target = dest;
3493 scan(tree.value);
3494 }
3495 public void visitContinue(JCContinue tree) {
3496 if (tree.target == src)
3497 tree.target = dest;
3498 }
3499 public void visitClassDef(JCClassDecl tree) {}
3500 }
3501 new Patcher().scan(body);
3502 }
3503 /**
3504 * A statement of the form
3505 *
3506 * <pre>
3507 * for ( T v : coll ) stmt ;
3508 * </pre>
3509 *
3510 * (where coll implements {@code Iterable<? extends T>}) gets translated to
3511 *
3512 * <pre>{@code
3513 * for ( Iterator<? extends T> #i = coll.iterator(); #i.hasNext(); ) {
3514 * T v = (T) #i.next();
3515 * stmt;
3516 * }
3517 * }</pre>
3518 *
3519 * where #i is a freshly named synthetic local variable.
3520 */
3521 private void visitIterableForeachLoop(JCEnhancedForLoop tree) {
3522 make_at(tree.expr.pos());
3523 Type iteratorTarget = syms.objectType;
3524 Type iterableType = types.asSuper(types.cvarUpperBound(tree.expr.type.referenceProjectionOrSelf()),
3525 syms.iterableType.tsym);
3526 if (iterableType.getTypeArguments().nonEmpty())
3527 iteratorTarget = types.erasure(iterableType.getTypeArguments().head);
3528 Type eType = types.skipTypeVars(tree.expr.type, false);
3529 tree.expr.type = types.erasure(eType);
3530 if (eType.isCompound())
3531 tree.expr = make.TypeCast(types.erasure(iterableType), tree.expr);
3532 Symbol iterator = lookupMethod(tree.expr.pos(),
3533 names.iterator,
3534 eType,
3535 List.nil());
3536 VarSymbol itvar = new VarSymbol(SYNTHETIC, names.fromString("i" + target.syntheticNameChar()),
3537 types.erasure(types.asSuper(iterator.type.getReturnType().referenceProjectionOrSelf(), syms.iteratorType.tsym)),
3538 currentMethodSym);
3539
3540 JCStatement init = make.
3541 VarDef(itvar, make.App(make.Select(tree.expr, iterator)
3542 .setType(types.erasure(iterator.type))));
3543
3544 Symbol hasNext = lookupMethod(tree.expr.pos(),
3545 names.hasNext,
3546 itvar.type,
3547 List.nil());
3548 JCMethodInvocation cond = make.App(make.Select(make.Ident(itvar), hasNext));
3549 Symbol next = lookupMethod(tree.expr.pos(),
3550 names.next,
3551 itvar.type,
3552 List.nil());
3553 JCExpression vardefinit = make.App(make.Select(make.Ident(itvar), next));
3554 if (tree.var.type.isPrimitive())
3555 vardefinit = make.TypeCast(types.cvarUpperBound(iteratorTarget), vardefinit);
3556 else
3557 vardefinit = make.TypeCast(tree.var.type, vardefinit);
3558 JCVariableDecl indexDef = (JCVariableDecl)make.VarDef(tree.var.mods,
3559 tree.var.name,
3560 tree.var.vartype,
3561 vardefinit).setType(tree.var.type);
3562 indexDef.sym = tree.var.sym;
3563 JCBlock body = make.Block(0, List.of(indexDef, tree.body));
3564 body.endpos = TreeInfo.endPos(tree.body);
3565 result = translate(make.
3566 ForLoop(List.of(init),
3567 cond,
3568 List.nil(),
3569 body));
3570 patchTargets(body, tree, result);
3571 }
3572
3573 public void visitVarDef(JCVariableDecl tree) {
3574 MethodSymbol oldMethodSym = currentMethodSym;
3575 tree.mods = translate(tree.mods);
3576 tree.vartype = translate(tree.vartype);
3577 if (currentMethodSym == null) {
3578 // A class or instance field initializer.
3579 currentMethodSym =
3580 new MethodSymbol((tree.mods.flags&STATIC) | BLOCK,
3581 names.empty, null,
3582 currentClass);
3583 }
3584 if (tree.init != null) tree.init = translate(tree.init, tree.type);
3585 result = tree;
3586 currentMethodSym = oldMethodSym;
3587 }
3588
3589 public void visitBlock(JCBlock tree) {
3590 MethodSymbol oldMethodSym = currentMethodSym;
3591 if (currentMethodSym == null) {
3592 // Block is a static or instance initializer.
3593 currentMethodSym =
3594 new MethodSymbol(tree.flags | BLOCK,
3595 names.empty, null,
3596 currentClass);
3597 }
3598 super.visitBlock(tree);
3599 currentMethodSym = oldMethodSym;
3600 }
3601
3602 public void visitDoLoop(JCDoWhileLoop tree) {
3603 tree.body = translate(tree.body);
3604 tree.cond = translate(tree.cond, syms.booleanType);
3605 result = tree;
3606 }
3607
3608 public void visitWhileLoop(JCWhileLoop tree) {
3609 tree.cond = translate(tree.cond, syms.booleanType);
3610 tree.body = translate(tree.body);
3611 result = tree;
3612 }
3613
3614 public void visitWithField(JCWithField tree) {
3615 Type fieldType = tree.field.type;
3616 tree.field = translate(tree.field, tree);
3617 tree.value = translate(tree.value, fieldType); // important to use pre-translation type.
3618
3619 // If translated field is an Apply, we are
3620 // seeing an access method invocation. In this case, append
3621 // right hand side as last argument of the access method.
3622 if (tree.field.hasTag(APPLY)) {
3623 JCMethodInvocation app = (JCMethodInvocation) tree.field;
3624 app.args = List.of(tree.value).prependList(app.args);
3625 result = app;
3626 } else {
3627 result = tree;
3628 }
3629 }
3630
3631 public void visitForLoop(JCForLoop tree) {
3632 tree.init = translate(tree.init);
3633 if (tree.cond != null)
3634 tree.cond = translate(tree.cond, syms.booleanType);
3635 tree.step = translate(tree.step);
3636 tree.body = translate(tree.body);
3637 result = tree;
3638 }
3639
3640 public void visitReturn(JCReturn tree) {
3641 if (tree.expr != null)
3642 tree.expr = translate(tree.expr,
3643 types.erasure(currentMethodDef
3644 .restype.type));
3645 result = tree;
3646 }
3647
3648 public void visitSwitch(JCSwitch tree) {
3649 List<JCCase> cases = tree.patternSwitch ? addDefaultIfNeeded(tree.cases) : tree.cases;
3650 handleSwitch(tree, tree.selector, cases);
3651 }
3652
3653 @Override
3654 public void visitSwitchExpression(JCSwitchExpression tree) {
3655 List<JCCase> cases = addDefaultIfNeeded(tree.cases);
3656 handleSwitch(tree, tree.selector, cases);
3657 }
3658
3659 private List<JCCase> addDefaultIfNeeded(List<JCCase> cases) {
3660 if (cases.stream().flatMap(c -> c.labels.stream()).noneMatch(p -> p.hasTag(Tag.DEFAULTCASELABEL))) {
3661 JCThrow thr = make.Throw(makeNewClass(syms.incompatibleClassChangeErrorType,
3662 List.nil()));
3663 JCCase c = make.Case(JCCase.STATEMENT, List.of(make.DefaultCaseLabel()), List.of(thr), null);
3664 cases = cases.prepend(c);
3665 }
3666
3667 return cases;
3668 }
3669
3670 private void handleSwitch(JCTree tree, JCExpression selector, List<JCCase> cases) {
3671 //expand multiple label cases:
3672 ListBuffer<JCCase> convertedCases = new ListBuffer<>();
3673
3674 for (JCCase c : cases) {
3675 switch (c.labels.size()) {
3676 case 0: //default
3677 case 1: //single label
3678 convertedCases.append(c);
3679 break;
3680 default: //multiple labels, expand:
3681 //case C1, C2, C3: ...
3682 //=>
3683 //case C1:
3684 //case C2:
3685 //case C3: ...
3686 List<JCCaseLabel> patterns = c.labels;
3687 while (patterns.tail.nonEmpty()) {
3688 convertedCases.append(make_at(c.pos()).Case(JCCase.STATEMENT,
3689 List.of(patterns.head),
3690 List.nil(),
3691 null));
3692 patterns = patterns.tail;
3693 }
3694 c.labels = patterns;
3695 convertedCases.append(c);
3696 break;
3697 }
3698 }
3699
3700 for (JCCase c : convertedCases) {
3701 if (c.caseKind == JCCase.RULE && c.completesNormally) {
3702 JCBreak b = make.at(TreeInfo.endPos(c.stats.last())).Break(null);
3703 b.target = tree;
3704 c.stats = c.stats.append(b);
3705 }
3706 }
3707
3708 cases = convertedCases.toList();
3709
3710 Type selsuper = types.supertype(selector.type);
3711 boolean enumSwitch = selsuper != null &&
3712 (selector.type.tsym.flags() & ENUM) != 0;
3713 boolean stringSwitch = selsuper != null &&
3714 types.isSameType(selector.type, syms.stringType);
3715 boolean boxedSwitch = !enumSwitch && !stringSwitch && !selector.type.isPrimitive();
3716 selector = translate(selector, selector.type);
3717 cases = translateCases(cases);
3718 if (tree.hasTag(SWITCH)) {
3719 ((JCSwitch) tree).selector = selector;
3720 ((JCSwitch) tree).cases = cases;
3721 } else if (tree.hasTag(SWITCH_EXPRESSION)) {
3722 ((JCSwitchExpression) tree).selector = selector;
3723 ((JCSwitchExpression) tree).cases = cases;
3724 } else {
3725 Assert.error();
3726 }
3727 if (enumSwitch) {
3728 result = visitEnumSwitch(tree, selector, cases);
3729 } else if (stringSwitch) {
3730 result = visitStringSwitch(tree, selector, cases);
3731 } else if (boxedSwitch) {
3732 //An switch over boxed primitive. Pattern matching switches are already translated
3733 //by TransPatterns, so all non-primitive types are only boxed primitives:
3734 result = visitBoxedPrimitiveSwitch(tree, selector, cases);
3735 } else {
3736 result = tree;
3737 }
3738 }
3739
3740 public JCTree visitEnumSwitch(JCTree tree, JCExpression selector, List<JCCase> cases) {
3741 TypeSymbol enumSym = selector.type.tsym;
3742 EnumMapping map = mapForEnum(tree.pos(), enumSym);
3743 make_at(tree.pos());
3744 Symbol ordinalMethod = lookupMethod(tree.pos(),
3745 names.ordinal,
3746 selector.type,
3747 List.nil());
3748 JCExpression newSelector;
3749
3750 if (cases.stream().anyMatch(c -> TreeInfo.isNull(c.labels.head))) {
3751 //for enum switches with case null, do:
3752 //switch ($selector != null ? $mapVar[$selector.ordinal()] : -1) {...}
3753 //replacing case null with case -1:
3754 VarSymbol dollar_s = new VarSymbol(FINAL|SYNTHETIC,
3755 names.fromString("s" + tree.pos + this.target.syntheticNameChar()),
3756 selector.type,
3757 currentMethodSym);
3758 JCStatement var = make.at(tree.pos()).VarDef(dollar_s, selector).setType(dollar_s.type);
3759 newSelector = make.Indexed(map.mapVar,
3760 make.App(make.Select(make.Ident(dollar_s),
3761 ordinalMethod)));
3762 newSelector =
3763 make.LetExpr(List.of(var),
3764 make.Conditional(makeBinary(NE, make.Ident(dollar_s), makeNull()),
3765 newSelector,
3766 makeLit(syms.intType, -1))
3767 .setType(newSelector.type))
3768 .setType(newSelector.type);
3769 } else {
3770 newSelector = make.Indexed(map.mapVar,
3771 make.App(make.Select(selector,
3772 ordinalMethod)));
3773 }
3774 ListBuffer<JCCase> newCases = new ListBuffer<>();
3775 for (JCCase c : cases) {
3776 if (c.labels.head.isExpression()) {
3777 JCExpression pat;
3778 if (TreeInfo.isNull(c.labels.head)) {
3779 pat = makeLit(syms.intType, -1);
3780 } else {
3781 VarSymbol label = (VarSymbol)TreeInfo.symbol((JCExpression) c.labels.head);
3782 pat = map.forConstant(label);
3783 }
3784 newCases.append(make.Case(JCCase.STATEMENT, List.of(pat), c.stats, null));
3785 } else {
3786 newCases.append(c);
3787 }
3788 }
3789 JCTree enumSwitch;
3790 if (tree.hasTag(SWITCH)) {
3791 enumSwitch = make.Switch(newSelector, newCases.toList());
3792 } else if (tree.hasTag(SWITCH_EXPRESSION)) {
3793 enumSwitch = make.SwitchExpression(newSelector, newCases.toList());
3794 enumSwitch.setType(tree.type);
3795 } else {
3796 Assert.error();
3797 throw new AssertionError();
3798 }
3799 patchTargets(enumSwitch, tree, enumSwitch);
3800 return enumSwitch;
3801 }
3802
3803 public JCTree visitStringSwitch(JCTree tree, JCExpression selector, List<JCCase> caseList) {
3804 int alternatives = caseList.size();
3805
3806 if (alternatives == 0) { // Strange but legal possibility (only legal for switch statement)
3807 return make.at(tree.pos()).Exec(attr.makeNullCheck(selector));
3808 } else {
3809 /*
3810 * The general approach used is to translate a single
3811 * string switch statement into a series of two chained
3812 * switch statements: the first a synthesized statement
3813 * switching on the argument string's hash value and
3814 * computing a string's position in the list of original
3815 * case labels, if any, followed by a second switch on the
3816 * computed integer value. The second switch has the same
3817 * code structure as the original string switch statement
3818 * except that the string case labels are replaced with
3819 * positional integer constants starting at 0.
3820 *
3821 * The first switch statement can be thought of as an
3822 * inlined map from strings to their position in the case
3823 * label list. An alternate implementation would use an
3824 * actual Map for this purpose, as done for enum switches.
3825 *
3826 * With some additional effort, it would be possible to
3827 * use a single switch statement on the hash code of the
3828 * argument, but care would need to be taken to preserve
3829 * the proper control flow in the presence of hash
3830 * collisions and other complications, such as
3831 * fallthroughs. Switch statements with one or two
3832 * alternatives could also be specially translated into
3833 * if-then statements to omit the computation of the hash
3834 * code.
3835 *
3836 * The generated code assumes that the hashing algorithm
3837 * of String is the same in the compilation environment as
3838 * in the environment the code will run in. The string
3839 * hashing algorithm in the SE JDK has been unchanged
3840 * since at least JDK 1.2. Since the algorithm has been
3841 * specified since that release as well, it is very
3842 * unlikely to be changed in the future.
3843 *
3844 * Different hashing algorithms, such as the length of the
3845 * strings or a perfect hashing algorithm over the
3846 * particular set of case labels, could potentially be
3847 * used instead of String.hashCode.
3848 */
3849
3850 ListBuffer<JCStatement> stmtList = new ListBuffer<>();
3851
3852 // Map from String case labels to their original position in
3853 // the list of case labels.
3854 Map<String, Integer> caseLabelToPosition = new LinkedHashMap<>(alternatives + 1, 1.0f);
3855
3856 // Map of hash codes to the string case labels having that hashCode.
3857 Map<Integer, Set<String>> hashToString = new LinkedHashMap<>(alternatives + 1, 1.0f);
3858
3859 int casePosition = 0;
3860 JCCase nullCase = null;
3861 int nullCaseLabel = -1;
3862
3863 for(JCCase oneCase : caseList) {
3864 if (oneCase.labels.head.isExpression()) {
3865 if (TreeInfo.isNull(oneCase.labels.head)) {
3866 nullCase = oneCase;
3867 nullCaseLabel = casePosition;
3868 } else {
3869 JCExpression expression = (JCExpression) oneCase.labels.head;
3870 String labelExpr = (String) expression.type.constValue();
3871 Integer mapping = caseLabelToPosition.put(labelExpr, casePosition);
3872 Assert.checkNull(mapping);
3873 int hashCode = labelExpr.hashCode();
3874
3875 Set<String> stringSet = hashToString.get(hashCode);
3876 if (stringSet == null) {
3877 stringSet = new LinkedHashSet<>(1, 1.0f);
3878 stringSet.add(labelExpr);
3879 hashToString.put(hashCode, stringSet);
3880 } else {
3881 boolean added = stringSet.add(labelExpr);
3882 Assert.check(added);
3883 }
3884 }
3885 }
3886 casePosition++;
3887 }
3888
3889 // Synthesize a switch statement that has the effect of
3890 // mapping from a string to the integer position of that
3891 // string in the list of case labels. This is done by
3892 // switching on the hashCode of the string followed by an
3893 // if-then-else chain comparing the input for equality
3894 // with all the case labels having that hash value.
3895
3896 /*
3897 * s$ = top of stack;
3898 * tmp$ = -1;
3899 * switch($s.hashCode()) {
3900 * case caseLabel.hashCode:
3901 * if (s$.equals("caseLabel_1")
3902 * tmp$ = caseLabelToPosition("caseLabel_1");
3903 * else if (s$.equals("caseLabel_2"))
3904 * tmp$ = caseLabelToPosition("caseLabel_2");
3905 * ...
3906 * break;
3907 * ...
3908 * }
3909 */
3910
3911 VarSymbol dollar_s = new VarSymbol(FINAL|SYNTHETIC,
3912 names.fromString("s" + tree.pos + target.syntheticNameChar()),
3913 syms.stringType,
3914 currentMethodSym);
3915 stmtList.append(make.at(tree.pos()).VarDef(dollar_s, selector).setType(dollar_s.type));
3916
3917 VarSymbol dollar_tmp = new VarSymbol(SYNTHETIC,
3918 names.fromString("tmp" + tree.pos + target.syntheticNameChar()),
3919 syms.intType,
3920 currentMethodSym);
3921 JCVariableDecl dollar_tmp_def =
3922 (JCVariableDecl)make.VarDef(dollar_tmp, make.Literal(INT, -1)).setType(dollar_tmp.type);
3923 dollar_tmp_def.init.type = dollar_tmp.type = syms.intType;
3924 stmtList.append(dollar_tmp_def);
3925 ListBuffer<JCCase> caseBuffer = new ListBuffer<>();
3926 // hashCode will trigger nullcheck on original switch expression
3927 JCMethodInvocation hashCodeCall = makeCall(make.Ident(dollar_s),
3928 names.hashCode,
3929 List.nil()).setType(syms.intType);
3930 JCSwitch switch1 = make.Switch(hashCodeCall,
3931 caseBuffer.toList());
3932 for(Map.Entry<Integer, Set<String>> entry : hashToString.entrySet()) {
3933 int hashCode = entry.getKey();
3934 Set<String> stringsWithHashCode = entry.getValue();
3935 Assert.check(stringsWithHashCode.size() >= 1);
3936
3937 JCStatement elsepart = null;
3938 for(String caseLabel : stringsWithHashCode ) {
3939 JCMethodInvocation stringEqualsCall = makeCall(make.Ident(dollar_s),
3940 names.equals,
3941 List.of(make.Literal(caseLabel)));
3942 elsepart = make.If(stringEqualsCall,
3943 make.Exec(make.Assign(make.Ident(dollar_tmp),
3944 make.Literal(caseLabelToPosition.get(caseLabel))).
3945 setType(dollar_tmp.type)),
3946 elsepart);
3947 }
3948
3949 ListBuffer<JCStatement> lb = new ListBuffer<>();
3950 JCBreak breakStmt = make.Break(null);
3951 breakStmt.target = switch1;
3952 lb.append(elsepart).append(breakStmt);
3953
3954 caseBuffer.append(make.Case(JCCase.STATEMENT, List.of(make.Literal(hashCode)), lb.toList(), null));
3955 }
3956
3957 switch1.cases = caseBuffer.toList();
3958
3959 if (nullCase != null) {
3960 stmtList.append(make.If(makeBinary(NE, make.Ident(dollar_s), makeNull()), switch1, make.Exec(make.Assign(make.Ident(dollar_tmp),
3961 make.Literal(nullCaseLabel)).
3962 setType(dollar_tmp.type))).setType(syms.intType));
3963 } else {
3964 stmtList.append(switch1);
3965 }
3966
3967 // Make isomorphic switch tree replacing string labels
3968 // with corresponding integer ones from the label to
3969 // position map.
3970
3971 ListBuffer<JCCase> lb = new ListBuffer<>();
3972 for(JCCase oneCase : caseList ) {
3973 boolean isDefault = !oneCase.labels.head.isExpression();
3974 JCCaseLabel caseExpr;
3975 if (isDefault)
3976 caseExpr = null;
3977 else if (oneCase == nullCase) {
3978 caseExpr = make.Literal(nullCaseLabel);
3979 } else {
3980 caseExpr = make.Literal(caseLabelToPosition.get((String)TreeInfo.skipParens((JCExpression) oneCase.labels.head).
3981 type.constValue()));
3982 }
3983
3984 lb.append(make.Case(JCCase.STATEMENT, caseExpr == null ? List.of(make.DefaultCaseLabel()) : List.of(caseExpr),
3985 oneCase.stats, null));
3986 }
3987
3988 if (tree.hasTag(SWITCH)) {
3989 JCSwitch switch2 = make.Switch(make.Ident(dollar_tmp), lb.toList());
3990 // Rewire up old unlabeled break statements to the
3991 // replacement switch being created.
3992 patchTargets(switch2, tree, switch2);
3993
3994 stmtList.append(switch2);
3995
3996 JCBlock res = make.Block(0L, stmtList.toList());
3997 res.endpos = TreeInfo.endPos(tree);
3998 return res;
3999 } else {
4000 JCSwitchExpression switch2 = make.SwitchExpression(make.Ident(dollar_tmp), lb.toList());
4001
4002 // Rewire up old unlabeled break statements to the
4003 // replacement switch being created.
4004 patchTargets(switch2, tree, switch2);
4005
4006 switch2.setType(tree.type);
4007
4008 LetExpr res = make.LetExpr(stmtList.toList(), switch2);
4009
4010 res.needsCond = true;
4011 res.setType(tree.type);
4012
4013 return res;
4014 }
4015 }
4016 }
4017
4018 private JCTree visitBoxedPrimitiveSwitch(JCTree tree, JCExpression selector, List<JCCase> cases) {
4019 JCExpression newSelector;
4020
4021 if (cases.stream().anyMatch(c -> TreeInfo.isNull(c.labels.head))) {
4022 //a switch over a boxed primitive, with a null case. Pick two constants that are
4023 //not used by any branch in the case (c1 and c2), close to other constants that are
4024 //used in the switch. Then do:
4025 //switch ($selector != null ? $selector != c1 ? $selector : c2 : c1) {...}
4026 //replacing case null with case c1
4027 Set<Integer> constants = new LinkedHashSet<>();
4028 JCCase nullCase = null;
4029
4030 for (JCCase c : cases) {
4031 if (TreeInfo.isNull(c.labels.head)) {
4032 nullCase = c;
4033 } else if (!c.labels.head.hasTag(DEFAULTCASELABEL)) {
4034 constants.add((int) c.labels.head.type.constValue());
4035 }
4036 }
4037
4038 Assert.checkNonNull(nullCase);
4039
4040 int nullValue = constants.isEmpty() ? 0 : constants.iterator().next();
4041
4042 while (constants.contains(nullValue)) nullValue++;
4043
4044 constants.add(nullValue);
4045 nullCase.labels.head = makeLit(syms.intType, nullValue);
4046
4047 int replacementValue = nullValue;
4048
4049 while (constants.contains(replacementValue)) replacementValue++;
4050
4051 VarSymbol dollar_s = new VarSymbol(FINAL|SYNTHETIC,
4052 names.fromString("s" + tree.pos + this.target.syntheticNameChar()),
4053 selector.type,
4054 currentMethodSym);
4055 JCStatement var = make.at(tree.pos()).VarDef(dollar_s, selector).setType(dollar_s.type);
4056 JCExpression nullValueReplacement =
4057 make.Conditional(makeBinary(NE,
4058 unbox(make.Ident(dollar_s), syms.intType),
4059 makeLit(syms.intType, nullValue)),
4060 unbox(make.Ident(dollar_s), syms.intType),
4061 makeLit(syms.intType, replacementValue))
4062 .setType(syms.intType);
4063 JCExpression nullCheck =
4064 make.Conditional(makeBinary(NE, make.Ident(dollar_s), makeNull()),
4065 nullValueReplacement,
4066 makeLit(syms.intType, nullValue))
4067 .setType(syms.intType);
4068 newSelector = make.LetExpr(List.of(var), nullCheck).setType(syms.intType);
4069 } else {
4070 newSelector = unbox(selector, syms.intType);
4071 }
4072
4073 if (tree.hasTag(SWITCH)) {
4074 ((JCSwitch) tree).selector = newSelector;
4075 } else {
4076 ((JCSwitchExpression) tree).selector = newSelector;
4077 }
4078
4079 return tree;
4080 }
4081
4082 @Override
4083 public void visitBreak(JCBreak tree) {
4084 result = tree;
4085 }
4086
4087 @Override
4088 public void visitYield(JCYield tree) {
4089 tree.value = translate(tree.value, tree.target.type);
4090 result = tree;
4091 }
4092
4093 public void visitNewArray(JCNewArray tree) {
4094 tree.elemtype = translate(tree.elemtype);
4095 for (List<JCExpression> t = tree.dims; t.tail != null; t = t.tail)
4096 if (t.head != null) t.head = translate(t.head, syms.intType);
4097 tree.elems = translate(tree.elems, types.elemtype(tree.type));
4098 result = tree;
4099 }
4100
4101 public void visitSelect(JCFieldAccess tree) {
4102 // need to special case-access of the form C.super.x
4103 // these will always need an access method, unless C
4104 // is a default interface subclassed by the current class.
4105 boolean qualifiedSuperAccess =
4106 tree.selected.hasTag(SELECT) &&
4107 TreeInfo.name(tree.selected) == names._super &&
4108 !types.isDirectSuperInterface(((JCFieldAccess)tree.selected).selected.type.tsym, currentClass);
4109 /* JDK-8269956: Where a reflective (class) literal is needed, the unqualified Point.class is
4110 * always the "primary" mirror - representing the primitive reference runtime type - thereby
4111 * always matching the behavior of Object::getClass
4112 */
4113 boolean needPrimaryMirror = tree.name == names._class && tree.selected.type.isPrimitiveReferenceType();
4114 tree.selected = translate(tree.selected);
4115 if (needPrimaryMirror && tree.selected.type.isPrimitiveClass()) {
4116 tree.selected.setType(tree.selected.type.referenceProjection());
4117 }
4118 if (tree.name == names._class) {
4119 result = classOf(tree.selected);
4120 }
4121 else if (tree.name == names._super &&
4122 types.isDirectSuperInterface(tree.selected.type.tsym, currentClass)) {
4123 //default super call!! Not a classic qualified super call
4124 TypeSymbol supSym = tree.selected.type.tsym;
4125 Assert.checkNonNull(types.asSuper(currentClass.type.referenceProjectionOrSelf(), supSym));
4126 result = tree;
4127 }
4128 else if (tree.name == names._this || tree.name == names._super) {
4129 result = makeThis(tree.pos(), tree.selected.type.tsym);
4130 }
4131 else
4132 result = access(tree.sym, tree, enclOp, qualifiedSuperAccess);
4133 }
4134
4135 public void visitLetExpr(LetExpr tree) {
4136 tree.defs = translate(tree.defs);
4137 tree.expr = translate(tree.expr, tree.type);
4138 result = tree;
4139 }
4140
4141 // There ought to be nothing to rewrite here;
4142 // we don't generate code.
4143 public void visitAnnotation(JCAnnotation tree) {
4144 result = tree;
4145 }
4146
4147 @Override
4148 public void visitTry(JCTry tree) {
4149 if (tree.resources.nonEmpty()) {
4150 result = makeTwrTry(tree);
4151 return;
4152 }
4153
4154 boolean hasBody = tree.body.getStatements().nonEmpty();
4155 boolean hasCatchers = tree.catchers.nonEmpty();
4156 boolean hasFinally = tree.finalizer != null &&
4157 tree.finalizer.getStatements().nonEmpty();
4158
4159 if (!hasCatchers && !hasFinally) {
4160 result = translate(tree.body);
4161 return;
4162 }
4163
4164 if (!hasBody) {
4165 if (hasFinally) {
4166 result = translate(tree.finalizer);
4167 } else {
4168 result = translate(tree.body);
4169 }
4170 return;
4171 }
4172
4173 // no optimizations possible
4174 super.visitTry(tree);
4175 }
4176
4177 /**************************************************************************
4178 * main method
4179 *************************************************************************/
4180
4181 /** Translate a toplevel class and return a list consisting of
4182 * the translated class and translated versions of all inner classes.
4183 * @param env The attribution environment current at the class definition.
4184 * We need this for resolving some additional symbols.
4185 * @param cdef The tree representing the class definition.
4186 */
4187 public List<JCTree> translateTopLevelClass(Env<AttrContext> env, JCTree cdef, TreeMaker make) {
4188 ListBuffer<JCTree> translated = null;
4189 try {
4190 attrEnv = env;
4191 this.make = make;
4192 endPosTable = env.toplevel.endPositions;
4193 currentClass = null;
4194 currentMethodDef = null;
4195 outermostClassDef = (cdef.hasTag(CLASSDEF)) ? (JCClassDecl)cdef : null;
4196 outermostMemberDef = null;
4197 this.translated = new ListBuffer<>();
4198 classdefs = new HashMap<>();
4199 actualSymbols = new HashMap<>();
4200 freevarCache = new HashMap<>();
4201 proxies = new HashMap<>();
4202 twrVars = WriteableScope.create(syms.noSymbol);
4203 outerThisStack = List.nil();
4204 accessNums = new HashMap<>();
4205 accessSyms = new HashMap<>();
4206 accessConstrs = new HashMap<>();
4207 accessConstrTags = List.nil();
4208 accessed = new ListBuffer<>();
4209 translate(cdef, (JCExpression)null);
4210 for (List<Symbol> l = accessed.toList(); l.nonEmpty(); l = l.tail)
4211 makeAccessible(l.head);
4212 for (EnumMapping map : enumSwitchMap.values())
4213 map.translate();
4214 checkConflicts(this.translated.toList());
4215 checkAccessConstructorTags();
4216 translated = this.translated;
4217 } finally {
4218 // note that recursive invocations of this method fail hard
4219 attrEnv = null;
4220 this.make = null;
4221 endPosTable = null;
4222 currentClass = null;
4223 currentMethodDef = null;
4224 outermostClassDef = null;
4225 outermostMemberDef = null;
4226 this.translated = null;
4227 classdefs = null;
4228 actualSymbols = null;
4229 freevarCache = null;
4230 proxies = null;
4231 outerThisStack = null;
4232 accessNums = null;
4233 accessSyms = null;
4234 accessConstrs = null;
4235 accessConstrTags = null;
4236 accessed = null;
4237 enumSwitchMap.clear();
4238 assertionsDisabledClassCache = null;
4239 }
4240 return translated.toList();
4241 }
4242 }