1 /*
2 * Copyright (c) 1999, 2022, Oracle and/or its affiliates. All rights reserved.
3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
4 *
5 * This code is free software; you can redistribute it and/or modify it
6 * under the terms of the GNU General Public License version 2 only, as
7 * published by the Free Software Foundation. Oracle designates this
8 * particular file as subject to the "Classpath" exception as provided
9 * by Oracle in the LICENSE file that accompanied this code.
10 *
11 * This code is distributed in the hope that it will be useful, but WITHOUT
12 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
13 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
14 * version 2 for more details (a copy is included in the LICENSE file that
15 * accompanied this code).
16 *
17 * You should have received a copy of the GNU General Public License version
18 * 2 along with this work; if not, write to the Free Software Foundation,
19 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
20 *
21 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
22 * or visit www.oracle.com if you need additional information or have any
23 * questions.
24 */
25
26 package com.sun.tools.javac.comp;
27
28 import java.util.*;
29 import java.util.stream.Collectors;
30
31 import com.sun.source.tree.LambdaExpressionTree.BodyKind;
32 import com.sun.tools.javac.code.*;
33 import com.sun.tools.javac.code.Kinds.KindSelector;
34 import com.sun.tools.javac.code.Scope.WriteableScope;
35 import com.sun.tools.javac.jvm.*;
36 import com.sun.tools.javac.jvm.PoolConstant.LoadableConstant;
37 import com.sun.tools.javac.main.Option.PkgInfo;
38 import com.sun.tools.javac.resources.CompilerProperties.Fragments;
39 import com.sun.tools.javac.resources.CompilerProperties.Notes;
40 import com.sun.tools.javac.tree.*;
41 import com.sun.tools.javac.util.*;
42 import com.sun.tools.javac.util.JCDiagnostic.DiagnosticPosition;
43 import com.sun.tools.javac.util.List;
44
45 import com.sun.tools.javac.code.Symbol.*;
46 import com.sun.tools.javac.code.Symbol.OperatorSymbol.AccessCode;
47 import com.sun.tools.javac.resources.CompilerProperties.Errors;
48 import com.sun.tools.javac.tree.JCTree.*;
49 import com.sun.tools.javac.code.Type.*;
50
51 import com.sun.tools.javac.jvm.Target;
52 import com.sun.tools.javac.tree.EndPosTable;
53
54 import static com.sun.tools.javac.code.Flags.*;
55 import static com.sun.tools.javac.code.Flags.BLOCK;
56 import static com.sun.tools.javac.code.Scope.LookupKind.NON_RECURSIVE;
57 import static com.sun.tools.javac.code.TypeTag.*;
58 import static com.sun.tools.javac.code.Kinds.Kind.*;
59 import com.sun.tools.javac.code.Source.Feature;
60 import static com.sun.tools.javac.jvm.ByteCodes.*;
61 import com.sun.tools.javac.tree.JCTree.JCBreak;
62 import com.sun.tools.javac.tree.JCTree.JCCase;
63 import com.sun.tools.javac.tree.JCTree.JCExpression;
64 import com.sun.tools.javac.tree.JCTree.JCExpressionStatement;
65
66 import static com.sun.tools.javac.tree.JCTree.JCOperatorExpression.OperandPos.LEFT;
67 import com.sun.tools.javac.tree.JCTree.JCSwitchExpression;
68
69 import static com.sun.tools.javac.tree.JCTree.Tag.*;
70
71 /** This pass translates away some syntactic sugar: inner classes,
72 * class literals, assertions, foreach loops, etc.
73 *
74 * <p><b>This is NOT part of any supported API.
75 * If you write code that depends on this, you do so at your own risk.
76 * This code and its internal interfaces are subject to change or
77 * deletion without notice.</b>
78 */
79 public class Lower extends TreeTranslator {
80 protected static final Context.Key<Lower> lowerKey = new Context.Key<>();
81
82 public static Lower instance(Context context) {
83 Lower instance = context.get(lowerKey);
84 if (instance == null)
85 instance = new Lower(context);
86 return instance;
87 }
88
89 private final Names names;
90 private final Log log;
91 private final Symtab syms;
92 private final Resolve rs;
93 private final Operators operators;
94 private final Check chk;
95 private final Attr attr;
96 private TreeMaker make;
97 private DiagnosticPosition make_pos;
98 private final ConstFold cfolder;
99 private final Target target;
100 private final TypeEnvs typeEnvs;
101 private final Name dollarAssertionsDisabled;
102 private final Types types;
103 private final TransTypes transTypes;
104 private final boolean debugLower;
105 private final boolean disableProtectedAccessors; // experimental
106 private final PkgInfo pkginfoOpt;
107 private final boolean optimizeOuterThis;
108 private final boolean useMatchException;
109 private final HashMap<TypePairs, String> typePairToName;
110 private int variableIndex = 0;
111
112 @SuppressWarnings("this-escape")
113 protected Lower(Context context) {
114 context.put(lowerKey, this);
115 names = Names.instance(context);
116 log = Log.instance(context);
117 syms = Symtab.instance(context);
118 rs = Resolve.instance(context);
119 operators = Operators.instance(context);
120 chk = Check.instance(context);
121 attr = Attr.instance(context);
122 make = TreeMaker.instance(context);
123 cfolder = ConstFold.instance(context);
124 target = Target.instance(context);
125 typeEnvs = TypeEnvs.instance(context);
126 dollarAssertionsDisabled = names.
127 fromString(target.syntheticNameChar() + "assertionsDisabled");
128
129 types = Types.instance(context);
130 transTypes = TransTypes.instance(context);
131 Options options = Options.instance(context);
132 debugLower = options.isSet("debuglower");
133 pkginfoOpt = PkgInfo.get(options);
134 optimizeOuterThis =
135 target.optimizeOuterThis() ||
136 options.getBoolean("optimizeOuterThis", false);
137 disableProtectedAccessors = options.isSet("disableProtectedAccessors");
138 Source source = Source.instance(context);
139 Preview preview = Preview.instance(context);
140 useMatchException = Feature.PATTERN_SWITCH.allowedInSource(source) &&
141 (preview.isEnabled() || !preview.isPreview(Feature.PATTERN_SWITCH));
142 typePairToName = TypePairs.initialize(syms);
143 }
144
145 /** The currently enclosing class.
146 */
147 ClassSymbol currentClass;
148
149 /** A queue of all translated classes.
150 */
151 ListBuffer<JCTree> translated;
152
153 /** Environment for symbol lookup, set by translateTopLevelClass.
154 */
155 Env<AttrContext> attrEnv;
156
157 /** A hash table mapping syntax trees to their ending source positions.
158 */
159 EndPosTable endPosTable;
160
161 /* ************************************************************************
162 * Global mappings
163 *************************************************************************/
164
165 /** A hash table mapping local classes to their definitions.
166 */
167 Map<ClassSymbol, JCClassDecl> classdefs;
168
169 /** A hash table mapping local classes to a list of pruned trees.
170 */
171 public Map<ClassSymbol, List<JCTree>> prunedTree = new WeakHashMap<>();
172
173 /** A hash table mapping virtual accessed symbols in outer subclasses
174 * to the actually referred symbol in superclasses.
175 */
176 Map<Symbol,Symbol> actualSymbols;
177
178 /**
179 * The current expected return type.
180 */
181 Type currentRestype;
182
183 /** The current method definition.
184 */
185 JCMethodDecl currentMethodDef;
186
187 /** The current method symbol.
188 */
189 MethodSymbol currentMethodSym;
190
191 /** The currently enclosing outermost class definition.
192 */
193 JCClassDecl outermostClassDef;
194
195 /** The currently enclosing outermost member definition.
196 */
197 JCTree outermostMemberDef;
198
199 /** A navigator class for assembling a mapping from local class symbols
200 * to class definition trees.
201 * There is only one case; all other cases simply traverse down the tree.
202 */
203 class ClassMap extends TreeScanner {
204
205 /** All encountered class defs are entered into classdefs table.
206 */
207 public void visitClassDef(JCClassDecl tree) {
208 classdefs.put(tree.sym, tree);
209 super.visitClassDef(tree);
210 }
211 }
212 ClassMap classMap = new ClassMap();
213
214 /** Map a class symbol to its definition.
215 * @param c The class symbol of which we want to determine the definition.
216 */
217 JCClassDecl classDef(ClassSymbol c) {
218 // First lookup the class in the classdefs table.
219 JCClassDecl def = classdefs.get(c);
220 if (def == null && outermostMemberDef != null) {
221 // If this fails, traverse outermost member definition, entering all
222 // local classes into classdefs, and try again.
223 classMap.scan(outermostMemberDef);
224 def = classdefs.get(c);
225 }
226 if (def == null) {
227 // If this fails, traverse outermost class definition, entering all
228 // local classes into classdefs, and try again.
229 classMap.scan(outermostClassDef);
230 def = classdefs.get(c);
231 }
232 return def;
233 }
234
235 /**
236 * Get the enum constants for the given enum class symbol, if known.
237 * They will only be found if they are defined within the same top-level
238 * class as the class being compiled, so it's safe to assume that they
239 * can't change at runtime due to a recompilation.
240 */
241 List<Name> enumNamesFor(ClassSymbol c) {
242
243 // Find the class definition and verify it is an enum class
244 final JCClassDecl classDef = classDef(c);
245 if (classDef == null ||
246 (classDef.mods.flags & ENUM) == 0 ||
247 (types.supertype(currentClass.type).tsym.flags() & ENUM) != 0) {
248 return null;
249 }
250
251 // Gather the enum identifiers
252 ListBuffer<Name> idents = new ListBuffer<>();
253 for (List<JCTree> defs = classDef.defs; defs.nonEmpty(); defs=defs.tail) {
254 if (defs.head.hasTag(VARDEF) &&
255 (((JCVariableDecl) defs.head).mods.flags & ENUM) != 0) {
256 JCVariableDecl var = (JCVariableDecl)defs.head;
257 idents.append(var.name);
258 }
259 }
260 return idents.toList();
261 }
262
263 /** A hash table mapping class symbols to lists of free variables.
264 * accessed by them. Only free variables of the method immediately containing
265 * a class are associated with that class.
266 */
267 Map<ClassSymbol,List<VarSymbol>> freevarCache;
268
269 /** A navigator class for collecting the free variables accessed
270 * from a local class.
271 */
272 public class FreeVarCollector extends CaptureScanner {
273
274 protected FreeVarCollector(JCTree ownerTree) {
275 super(ownerTree);
276 }
277
278 protected void addFreeVars(ClassSymbol c) {
279 List<VarSymbol> fvs = freevarCache.get(c);
280 if (fvs != null) {
281 for (List<VarSymbol> l = fvs; l.nonEmpty(); l = l.tail) {
282 addFreeVar(l.head);
283 }
284 }
285 }
286
287 /** If tree refers to a class instance creation expression
288 * add all free variables of the freshly created class.
289 */
290 public void visitNewClass(JCNewClass tree) {
291 ClassSymbol c = (ClassSymbol)tree.constructor.owner;
292 addFreeVars(c);
293 super.visitNewClass(tree);
294 }
295
296 /** If tree refers to a superclass constructor call,
297 * add all free variables of the superclass.
298 */
299 public void visitApply(JCMethodInvocation tree) {
300 if (TreeInfo.name(tree.meth) == names._super) {
301 addFreeVars((ClassSymbol) TreeInfo.symbol(tree.meth).owner);
302 }
303 super.visitApply(tree);
304 }
305 }
306
307 /** Return the variables accessed from within a local class, which
308 * are declared in the local class' owner.
309 * (in reverse order of first access).
310 */
311 List<VarSymbol> freevars(ClassSymbol c) {
312 List<VarSymbol> fvs = freevarCache.get(c);
313 if (fvs != null) {
314 return fvs;
315 }
316 FreeVarCollector collector = new FreeVarCollector(classDef(c));
317 fvs = collector.analyzeCaptures().reverse();
318 freevarCache.put(c, fvs);
319 return fvs;
320 }
321
322 Map<TypeSymbol,EnumMapping> enumSwitchMap = new LinkedHashMap<>();
323
324 EnumMapping mapForEnum(DiagnosticPosition pos, TypeSymbol enumClass) {
325
326 // If enum class is part of this compilation, just switch on ordinal value
327 if (enumClass.kind == TYP) {
328 final List<Name> idents = enumNamesFor((ClassSymbol)enumClass);
329 if (idents != null)
330 return new CompileTimeEnumMapping(idents);
331 }
332
333 // Map identifiers to ordinal values at runtime, and then switch on that
334 return enumSwitchMap.computeIfAbsent(enumClass, ec -> new RuntimeEnumMapping(pos, ec));
335 }
336
337 /** Generates a test value and corresponding cases for a switch on an enum type.
338 */
339 interface EnumMapping {
340
341 /** Given an expression for the enum value's ordinal, generate an expression for the switch statement.
342 */
343 JCExpression switchValue(JCExpression ordinalExpr);
344
345 /** Generate the switch statement case value corresponding to the given enum value.
346 */
347 JCLiteral caseValue(VarSymbol v);
348
349 default void translate() {
350 }
351 }
352
353 /** EnumMapping using compile-time constants. Only valid when compiling the enum class itself,
354 * because otherwise the ordinals we use could become obsolete if/when the enum class is recompiled.
355 */
356 class CompileTimeEnumMapping implements EnumMapping {
357
358 final List<Name> enumNames;
359
360 CompileTimeEnumMapping(List<Name> enumNames) {
361 Assert.check(enumNames != null);
362 this.enumNames = enumNames;
363 }
364
365 @Override
366 public JCExpression switchValue(JCExpression ordinalExpr) {
367 return ordinalExpr;
368 }
369
370 @Override
371 public JCLiteral caseValue(VarSymbol v) {
372 final int ordinal = enumNames.indexOf(v.name);
373 Assert.check(ordinal != -1);
374 return make.Literal(ordinal);
375 }
376 }
377
378 /** EnumMapping using run-time ordinal lookup.
379 *
380 * This builds a translation table to be used for enum switches.
381 *
382 * <p>For each enum that appears as the type of a switch
383 * expression, we maintain an EnumMapping to assist in the
384 * translation, as exemplified by the following example:
385 *
386 * <p>we translate
387 * <pre>
388 * switch(colorExpression) {
389 * case red: stmt1;
390 * case green: stmt2;
391 * }
392 * </pre>
393 * into
394 * <pre>
395 * switch(Outer$0.$EnumMap$Color[colorExpression.ordinal()]) {
396 * case 1: stmt1;
397 * case 2: stmt2
398 * }
399 * </pre>
400 * with the auxiliary table initialized as follows:
401 * <pre>
402 * class Outer$0 {
403 * synthetic final int[] $EnumMap$Color = new int[Color.values().length];
404 * static {
405 * try { $EnumMap$Color[red.ordinal()] = 1; } catch (NoSuchFieldError ex) {}
406 * try { $EnumMap$Color[green.ordinal()] = 2; } catch (NoSuchFieldError ex) {}
407 * }
408 * }
409 * </pre>
410 * class EnumMapping provides mapping data and support methods for this translation.
411 */
412 class RuntimeEnumMapping implements EnumMapping {
413 RuntimeEnumMapping(DiagnosticPosition pos, TypeSymbol forEnum) {
414 this.forEnum = forEnum;
415 this.values = new LinkedHashMap<>();
416 this.pos = pos;
417 Name varName = names
418 .fromString(target.syntheticNameChar() +
419 "SwitchMap" +
420 target.syntheticNameChar() +
421 ClassWriter.externalize(forEnum.type.tsym.flatName().toString())
422 .replace('/', '.')
423 .replace('.', target.syntheticNameChar()));
424 ClassSymbol outerCacheClass = outerCacheClass();
425 this.mapVar = new VarSymbol(STATIC | SYNTHETIC | FINAL,
426 varName,
427 new ArrayType(syms.intType, syms.arrayClass),
428 outerCacheClass);
429 enterSynthetic(pos, mapVar, outerCacheClass.members());
430 }
431
432 DiagnosticPosition pos = null;
433
434 // the next value to use
435 int next = 1; // 0 (unused map elements) go to the default label
436
437 // the enum for which this is a map
438 final TypeSymbol forEnum;
439
440 // the field containing the map
441 final VarSymbol mapVar;
442
443 // the mapped values
444 final Map<VarSymbol,Integer> values;
445
446 @Override
447 public JCExpression switchValue(JCExpression ordinalExpr) {
448 return make.Indexed(mapVar, ordinalExpr);
449 }
450
451 @Override
452 public JCLiteral caseValue(VarSymbol v) {
453 Integer result = values.get(v);
454 if (result == null)
455 values.put(v, result = next++);
456 return make.Literal(result);
457 }
458
459 // generate the field initializer for the map
460 @Override
461 public void translate() {
462 boolean prevAllowProtectedAccess = attrEnv.info.allowProtectedAccess;
463 try {
464 make.at(pos.getStartPosition());
465 attrEnv.info.allowProtectedAccess = true;
466 JCClassDecl owner = classDef((ClassSymbol)mapVar.owner);
467
468 // synthetic static final int[] $SwitchMap$Color = new int[Color.values().length];
469 MethodSymbol valuesMethod = lookupMethod(pos,
470 names.values,
471 forEnum.type,
472 List.nil());
473 JCExpression size = make // Color.values().length
474 .Select(make.App(make.QualIdent(valuesMethod)),
475 syms.lengthVar);
476 JCExpression mapVarInit = make
477 .NewArray(make.Type(syms.intType), List.of(size), null)
478 .setType(new ArrayType(syms.intType, syms.arrayClass));
479
480 // try { $SwitchMap$Color[red.ordinal()] = 1; } catch (java.lang.NoSuchFieldError ex) {}
481 ListBuffer<JCStatement> stmts = new ListBuffer<>();
482 Symbol ordinalMethod = lookupMethod(pos,
483 names.ordinal,
484 forEnum.type,
485 List.nil());
486 List<JCCatch> catcher = List.<JCCatch>nil()
487 .prepend(make.Catch(make.VarDef(new VarSymbol(PARAMETER, names.ex,
488 syms.noSuchFieldErrorType,
489 syms.noSymbol),
490 null),
491 make.Block(0, List.nil())));
492 for (Map.Entry<VarSymbol,Integer> e : values.entrySet()) {
493 VarSymbol enumerator = e.getKey();
494 Integer mappedValue = e.getValue();
495 JCExpression assign = make
496 .Assign(make.Indexed(mapVar,
497 make.App(make.Select(make.QualIdent(enumerator),
498 ordinalMethod))),
499 make.Literal(mappedValue))
500 .setType(syms.intType);
501 JCStatement exec = make.Exec(assign);
502 JCStatement _try = make.Try(make.Block(0, List.of(exec)), catcher, null);
503 stmts.append(_try);
504 }
505
506 owner.defs = owner.defs
507 .prepend(make.Block(STATIC, stmts.toList()))
508 .prepend(make.VarDef(mapVar, mapVarInit));
509 } finally {
510 attrEnv.info.allowProtectedAccess = prevAllowProtectedAccess;
511 }
512 }
513 }
514
515
516 /* ************************************************************************
517 * Tree building blocks
518 *************************************************************************/
519
520 /** Equivalent to make.at(pos.getStartPosition()) with side effect of caching
521 * pos as make_pos, for use in diagnostics.
522 **/
523 TreeMaker make_at(DiagnosticPosition pos) {
524 make_pos = pos;
525 return make.at(pos);
526 }
527
528 /** Make an attributed tree representing a literal. This will be an
529 * Ident node in the case of boolean literals, a Literal node in all
530 * other cases.
531 * @param type The literal's type.
532 * @param value The literal's value.
533 */
534 JCExpression makeLit(Type type, Object value) {
535 return make.Literal(type.getTag(), value).setType(type.constType(value));
536 }
537
538 /** Make an attributed tree representing null.
539 */
540 JCExpression makeNull() {
541 return makeLit(syms.botType, null);
542 }
543
544 /** Make an attributed class instance creation expression.
545 * @param ctype The class type.
546 * @param args The constructor arguments.
547 */
548 JCNewClass makeNewClass(Type ctype, List<JCExpression> args) {
549 JCNewClass tree = make.NewClass(null,
550 null, make.QualIdent(ctype.tsym), args, null);
551 tree.constructor = rs.resolveConstructor(
552 make_pos, attrEnv, ctype, TreeInfo.types(args), List.nil());
553 tree.type = ctype;
554 return tree;
555 }
556
557 /** Make an attributed unary expression.
558 * @param optag The operators tree tag.
559 * @param arg The operator's argument.
560 */
561 JCUnary makeUnary(JCTree.Tag optag, JCExpression arg) {
562 JCUnary tree = make.Unary(optag, arg);
563 tree.operator = operators.resolveUnary(tree, optag, arg.type);
564 tree.type = tree.operator.type.getReturnType();
565 return tree;
566 }
567
568 /** Make an attributed binary expression.
569 * @param optag The operators tree tag.
570 * @param lhs The operator's left argument.
571 * @param rhs The operator's right argument.
572 */
573 JCBinary makeBinary(JCTree.Tag optag, JCExpression lhs, JCExpression rhs) {
574 JCBinary tree = make.Binary(optag, lhs, rhs);
575 tree.operator = operators.resolveBinary(tree, optag, lhs.type, rhs.type);
576 tree.type = tree.operator.type.getReturnType();
577 return tree;
578 }
579
580 /** Make an attributed assignop expression.
581 * @param optag The operators tree tag.
582 * @param lhs The operator's left argument.
583 * @param rhs The operator's right argument.
584 */
585 JCAssignOp makeAssignop(JCTree.Tag optag, JCTree lhs, JCTree rhs) {
586 JCAssignOp tree = make.Assignop(optag, lhs, rhs);
587 tree.operator = operators.resolveBinary(tree, tree.getTag().noAssignOp(), lhs.type, rhs.type);
588 tree.type = lhs.type;
589 return tree;
590 }
591
592 /** Convert tree into string object, unless it has already a
593 * reference type..
594 */
595 JCExpression makeString(JCExpression tree) {
596 if (!tree.type.isPrimitiveOrVoid()) {
597 return tree;
598 } else {
599 Symbol valueOfSym = lookupMethod(tree.pos(),
600 names.valueOf,
601 syms.stringType,
602 List.of(tree.type));
603 return make.App(make.QualIdent(valueOfSym), List.of(tree));
604 }
605 }
606
607 /** Create an empty anonymous class definition and enter and complete
608 * its symbol. Return the class definition's symbol.
609 * and create
610 * @param flags The class symbol's flags
611 * @param owner The class symbol's owner
612 */
613 JCClassDecl makeEmptyClass(long flags, ClassSymbol owner) {
614 return makeEmptyClass(flags, owner, null, true);
615 }
616
617 JCClassDecl makeEmptyClass(long flags, ClassSymbol owner, Name flatname,
618 boolean addToDefs) {
619 // Create class symbol.
620 ClassSymbol c = syms.defineClass(names.empty, owner);
621 if (flatname != null) {
622 c.flatname = flatname;
623 } else {
624 c.flatname = chk.localClassName(c);
625 }
626 c.sourcefile = owner.sourcefile;
627 c.completer = Completer.NULL_COMPLETER;
628 c.members_field = WriteableScope.create(c);
629 c.flags_field = flags;
630 ClassType ctype = (ClassType) c.type;
631 ctype.supertype_field = syms.objectType;
632 ctype.interfaces_field = List.nil();
633
634 JCClassDecl odef = classDef(owner);
635
636 // Enter class symbol in owner scope and compiled table.
637 enterSynthetic(odef.pos(), c, owner.members());
638 chk.putCompiled(c);
639
640 // Create class definition tree.
641 JCClassDecl cdef = make.ClassDef(
642 make.Modifiers(flags), names.empty,
643 List.nil(),
644 null, List.nil(), List.nil());
645 cdef.sym = c;
646 cdef.type = c.type;
647
648 // Append class definition tree to owner's definitions.
649 if (addToDefs) odef.defs = odef.defs.prepend(cdef);
650 return cdef;
651 }
652
653 /* ************************************************************************
654 * Symbol manipulation utilities
655 *************************************************************************/
656
657 /** Enter a synthetic symbol in a given scope, but complain if there was already one there.
658 * @param pos Position for error reporting.
659 * @param sym The symbol.
660 * @param s The scope.
661 */
662 private void enterSynthetic(DiagnosticPosition pos, Symbol sym, WriteableScope s) {
663 s.enter(sym);
664 }
665
666 /** Create a fresh synthetic name within a given scope - the unique name is
667 * obtained by appending '$' chars at the end of the name until no match
668 * is found.
669 *
670 * @param name base name
671 * @param s scope in which the name has to be unique
672 * @return fresh synthetic name
673 */
674 private Name makeSyntheticName(Name name, Scope s) {
675 do {
676 name = name.append(
677 target.syntheticNameChar(),
678 names.empty);
679 } while (lookupSynthetic(name, s) != null);
680 return name;
681 }
682
683 /** Check whether synthetic symbols generated during lowering conflict
684 * with user-defined symbols.
685 *
686 * @param translatedTrees lowered class trees
687 */
688 void checkConflicts(List<JCTree> translatedTrees) {
689 for (JCTree t : translatedTrees) {
690 t.accept(conflictsChecker);
691 }
692 }
693
694 JCTree.Visitor conflictsChecker = new TreeScanner() {
695
696 TypeSymbol currentClass;
697
698 @Override
699 public void visitMethodDef(JCMethodDecl that) {
700 checkConflicts(that.pos(), that.sym, currentClass);
701 super.visitMethodDef(that);
702 }
703
704 @Override
705 public void visitVarDef(JCVariableDecl that) {
706 if (that.sym.owner.kind == TYP) {
707 checkConflicts(that.pos(), that.sym, currentClass);
708 }
709 super.visitVarDef(that);
710 }
711
712 @Override
713 public void visitClassDef(JCClassDecl that) {
714 TypeSymbol prevCurrentClass = currentClass;
715 currentClass = that.sym;
716 try {
717 super.visitClassDef(that);
718 }
719 finally {
720 currentClass = prevCurrentClass;
721 }
722 }
723
724 void checkConflicts(DiagnosticPosition pos, Symbol sym, TypeSymbol c) {
725 for (Type ct = c.type; ct != Type.noType ; ct = types.supertype(ct)) {
726 for (Symbol sym2 : ct.tsym.members().getSymbolsByName(sym.name, NON_RECURSIVE)) {
727 // VM allows methods and variables with differing types
728 if (sym.kind == sym2.kind &&
729 types.isSameType(types.erasure(sym.type), types.erasure(sym2.type)) &&
730 sym != sym2 &&
731 (sym.flags() & Flags.SYNTHETIC) != (sym2.flags() & Flags.SYNTHETIC) &&
732 (sym.flags() & BRIDGE) == 0 && (sym2.flags() & BRIDGE) == 0) {
733 syntheticError(pos, (sym2.flags() & SYNTHETIC) == 0 ? sym2 : sym);
734 return;
735 }
736 }
737 }
738 }
739
740 /** Report a conflict between a user symbol and a synthetic symbol.
741 */
742 private void syntheticError(DiagnosticPosition pos, Symbol sym) {
743 if (!sym.type.isErroneous()) {
744 log.error(pos, Errors.CannotGenerateClass(sym.location(), Fragments.SyntheticNameConflict(sym, sym.location())));
745 }
746 }
747 };
748
749 /** Look up a synthetic name in a given scope.
750 * @param s The scope.
751 * @param name The name.
752 */
753 private Symbol lookupSynthetic(Name name, Scope s) {
754 Symbol sym = s.findFirst(name);
755 return (sym==null || (sym.flags()&SYNTHETIC)==0) ? null : sym;
756 }
757
758 /** Look up a method in a given scope.
759 */
760 private MethodSymbol lookupMethod(DiagnosticPosition pos, Name name, Type qual, List<Type> args) {
761 return rs.resolveInternalMethod(pos, attrEnv, qual, name, args, List.nil());
762 }
763
764 /** Anon inner classes are used as access constructor tags.
765 * accessConstructorTag will use an existing anon class if one is available,
766 * and synthesize a class (with makeEmptyClass) if one is not available.
767 * However, there is a small possibility that an existing class will not
768 * be generated as expected if it is inside a conditional with a constant
769 * expression. If that is found to be the case, create an empty class tree here.
770 */
771 private void checkAccessConstructorTags() {
772 for (List<ClassSymbol> l = accessConstrTags; l.nonEmpty(); l = l.tail) {
773 ClassSymbol c = l.head;
774 if (isTranslatedClassAvailable(c))
775 continue;
776 // Create class definition tree.
777 JCClassDecl cdec = makeEmptyClass(STATIC | SYNTHETIC,
778 c.outermostClass(), c.flatname, false);
779 swapAccessConstructorTag(c, cdec.sym);
780 translated.append(cdec);
781 }
782 }
783 // where
784 private boolean isTranslatedClassAvailable(ClassSymbol c) {
785 for (JCTree tree: translated) {
786 if (tree.hasTag(CLASSDEF)
787 && ((JCClassDecl) tree).sym == c) {
788 return true;
789 }
790 }
791 return false;
792 }
793
794 void swapAccessConstructorTag(ClassSymbol oldCTag, ClassSymbol newCTag) {
795 for (MethodSymbol methodSymbol : accessConstrs.values()) {
796 Assert.check(methodSymbol.type.hasTag(METHOD));
797 MethodType oldMethodType =
798 (MethodType)methodSymbol.type;
799 if (oldMethodType.argtypes.head.tsym == oldCTag)
800 methodSymbol.type =
801 types.createMethodTypeWithParameters(oldMethodType,
802 oldMethodType.getParameterTypes().tail
803 .prepend(newCTag.erasure(types)));
804 }
805 }
806
807 /* ************************************************************************
808 * Access methods
809 *************************************************************************/
810
811 /** A mapping from symbols to their access numbers.
812 */
813 private Map<Symbol,Integer> accessNums;
814
815 /** A mapping from symbols to an array of access symbols, indexed by
816 * access code.
817 */
818 private Map<Symbol,MethodSymbol[]> accessSyms;
819
820 /** A mapping from (constructor) symbols to access constructor symbols.
821 */
822 private Map<Symbol,MethodSymbol> accessConstrs;
823
824 /** A list of all class symbols used for access constructor tags.
825 */
826 private List<ClassSymbol> accessConstrTags;
827
828 /** A queue for all accessed symbols.
829 */
830 private ListBuffer<Symbol> accessed;
831
832 /** return access code for identifier,
833 * @param tree The tree representing the identifier use.
834 * @param enclOp The closest enclosing operation node of tree,
835 * null if tree is not a subtree of an operation.
836 */
837 private static int accessCode(JCTree tree, JCTree enclOp) {
838 if (enclOp == null)
839 return AccessCode.DEREF.code;
840 else if (enclOp.hasTag(ASSIGN) &&
841 tree == TreeInfo.skipParens(((JCAssign) enclOp).lhs))
842 return AccessCode.ASSIGN.code;
843 else if ((enclOp.getTag().isIncOrDecUnaryOp() || enclOp.getTag().isAssignop()) &&
844 tree == TreeInfo.skipParens(((JCOperatorExpression) enclOp).getOperand(LEFT)))
845 return (((JCOperatorExpression) enclOp).operator).getAccessCode(enclOp.getTag());
846 else
847 return AccessCode.DEREF.code;
848 }
849
850 /** Return binary operator that corresponds to given access code.
851 */
852 private OperatorSymbol binaryAccessOperator(int acode, Tag tag) {
853 return operators.lookupBinaryOp(op -> op.getAccessCode(tag) == acode);
854 }
855
856 /** Return tree tag for assignment operation corresponding
857 * to given binary operator.
858 */
859 private static JCTree.Tag treeTag(OperatorSymbol operator) {
860 switch (operator.opcode) {
861 case ByteCodes.ior: case ByteCodes.lor:
862 return BITOR_ASG;
863 case ByteCodes.ixor: case ByteCodes.lxor:
864 return BITXOR_ASG;
865 case ByteCodes.iand: case ByteCodes.land:
866 return BITAND_ASG;
867 case ByteCodes.ishl: case ByteCodes.lshl:
868 case ByteCodes.ishll: case ByteCodes.lshll:
869 return SL_ASG;
870 case ByteCodes.ishr: case ByteCodes.lshr:
871 case ByteCodes.ishrl: case ByteCodes.lshrl:
872 return SR_ASG;
873 case ByteCodes.iushr: case ByteCodes.lushr:
874 case ByteCodes.iushrl: case ByteCodes.lushrl:
875 return USR_ASG;
876 case ByteCodes.iadd: case ByteCodes.ladd:
877 case ByteCodes.fadd: case ByteCodes.dadd:
878 case ByteCodes.string_add:
879 return PLUS_ASG;
880 case ByteCodes.isub: case ByteCodes.lsub:
881 case ByteCodes.fsub: case ByteCodes.dsub:
882 return MINUS_ASG;
883 case ByteCodes.imul: case ByteCodes.lmul:
884 case ByteCodes.fmul: case ByteCodes.dmul:
885 return MUL_ASG;
886 case ByteCodes.idiv: case ByteCodes.ldiv:
887 case ByteCodes.fdiv: case ByteCodes.ddiv:
888 return DIV_ASG;
889 case ByteCodes.imod: case ByteCodes.lmod:
890 case ByteCodes.fmod: case ByteCodes.dmod:
891 return MOD_ASG;
892 default:
893 throw new AssertionError();
894 }
895 }
896
897 /** The name of the access method with number `anum' and access code `acode'.
898 */
899 Name accessName(int anum, int acode) {
900 return names.fromString(
901 "access" + target.syntheticNameChar() + anum + acode / 10 + acode % 10);
902 }
903
904 /** Return access symbol for a private or protected symbol from an inner class.
905 * @param sym The accessed private symbol.
906 * @param tree The accessing tree.
907 * @param enclOp The closest enclosing operation node of tree,
908 * null if tree is not a subtree of an operation.
909 * @param protAccess Is access to a protected symbol in another
910 * package?
911 * @param refSuper Is access via a (qualified) C.super?
912 */
913 MethodSymbol accessSymbol(Symbol sym, JCTree tree, JCTree enclOp,
914 boolean protAccess, boolean refSuper) {
915 ClassSymbol accOwner = refSuper && protAccess
916 // For access via qualified super (T.super.x), place the
917 // access symbol on T.
918 ? (ClassSymbol)((JCFieldAccess) tree).selected.type.tsym
919 // Otherwise pretend that the owner of an accessed
920 // protected symbol is the enclosing class of the current
921 // class which is a subclass of the symbol's owner.
922 : accessClass(sym, protAccess, tree);
923
924 Symbol vsym = sym;
925 if (sym.owner != accOwner) {
926 vsym = sym.clone(accOwner);
927 actualSymbols.put(vsym, sym);
928 }
929
930 Integer anum // The access number of the access method.
931 = accessNums.get(vsym);
932 if (anum == null) {
933 anum = accessed.length();
934 accessNums.put(vsym, anum);
935 accessSyms.put(vsym, new MethodSymbol[AccessCode.numberOfAccessCodes]);
936 accessed.append(vsym);
937 // System.out.println("accessing " + vsym + " in " + vsym.location());
938 }
939
940 int acode; // The access code of the access method.
941 List<Type> argtypes; // The argument types of the access method.
942 Type restype; // The result type of the access method.
943 List<Type> thrown; // The thrown exceptions of the access method.
944 switch (vsym.kind) {
945 case VAR:
946 acode = accessCode(tree, enclOp);
947 if (acode >= AccessCode.FIRSTASGOP.code) {
948 OperatorSymbol operator = binaryAccessOperator(acode, enclOp.getTag());
949 if (operator.opcode == string_add)
950 argtypes = List.of(syms.objectType);
951 else
952 argtypes = operator.type.getParameterTypes().tail;
953 } else if (acode == AccessCode.ASSIGN.code)
954 argtypes = List.of(vsym.erasure(types));
955 else
956 argtypes = List.nil();
957 restype = vsym.erasure(types);
958 thrown = List.nil();
959 break;
960 case MTH:
961 acode = AccessCode.DEREF.code;
962 argtypes = vsym.erasure(types).getParameterTypes();
963 restype = vsym.erasure(types).getReturnType();
964 thrown = vsym.type.getThrownTypes();
965 break;
966 default:
967 throw new AssertionError();
968 }
969
970 // For references via qualified super, increment acode by one,
971 // making it odd.
972 if (protAccess && refSuper) acode++;
973
974 // Instance access methods get instance as first parameter.
975 // For protected symbols this needs to be the instance as a member
976 // of the type containing the accessed symbol, not the class
977 // containing the access method.
978 if ((vsym.flags() & STATIC) == 0) {
979 argtypes = argtypes.prepend(vsym.owner.erasure(types));
980 }
981 MethodSymbol[] accessors = accessSyms.get(vsym);
982 MethodSymbol accessor = accessors[acode];
983 if (accessor == null) {
984 accessor = new MethodSymbol(
985 STATIC | SYNTHETIC | (accOwner.isInterface() ? PUBLIC : 0),
986 accessName(anum.intValue(), acode),
987 new MethodType(argtypes, restype, thrown, syms.methodClass),
988 accOwner);
989 enterSynthetic(tree.pos(), accessor, accOwner.members());
990 accessors[acode] = accessor;
991 }
992 return accessor;
993 }
994
995 /** The qualifier to be used for accessing a symbol in an outer class.
996 * This is either C.sym or C.this.sym, depending on whether or not
997 * sym is static.
998 * @param sym The accessed symbol.
999 */
1000 JCExpression accessBase(DiagnosticPosition pos, Symbol sym) {
1001 return (sym.flags() & STATIC) != 0
1002 ? access(make.at(pos.getStartPosition()).QualIdent(sym.owner))
1003 : makeOwnerThis(pos, sym, true);
1004 }
1005
1006 /** Do we need an access method to reference private symbol?
1007 */
1008 boolean needsPrivateAccess(Symbol sym) {
1009 if (target.hasNestmateAccess()) {
1010 return false;
1011 }
1012 if ((sym.flags() & PRIVATE) == 0 || sym.owner == currentClass) {
1013 return false;
1014 } else if (sym.name == names.init && sym.owner.isDirectlyOrIndirectlyLocal()) {
1015 // private constructor in local class: relax protection
1016 sym.flags_field &= ~PRIVATE;
1017 return false;
1018 } else {
1019 return true;
1020 }
1021 }
1022
1023 /** Do we need an access method to reference symbol in other package?
1024 */
1025 boolean needsProtectedAccess(Symbol sym, JCTree tree) {
1026 if (disableProtectedAccessors) return false;
1027 if ((sym.flags() & PROTECTED) == 0 ||
1028 sym.owner.owner == currentClass.owner || // fast special case
1029 sym.packge() == currentClass.packge())
1030 return false;
1031 if (!currentClass.isSubClass(sym.owner, types))
1032 return true;
1033 if ((sym.flags() & STATIC) != 0 ||
1034 !tree.hasTag(SELECT) ||
1035 TreeInfo.name(((JCFieldAccess) tree).selected) == names._super)
1036 return false;
1037 return !((JCFieldAccess) tree).selected.type.tsym.isSubClass(currentClass, types);
1038 }
1039
1040 /** The class in which an access method for given symbol goes.
1041 * @param sym The access symbol
1042 * @param protAccess Is access to a protected symbol in another
1043 * package?
1044 */
1045 ClassSymbol accessClass(Symbol sym, boolean protAccess, JCTree tree) {
1046 if (protAccess) {
1047 Symbol qualifier = null;
1048 ClassSymbol c = currentClass;
1049 if (tree.hasTag(SELECT) && (sym.flags() & STATIC) == 0) {
1050 qualifier = ((JCFieldAccess) tree).selected.type.tsym;
1051 while (!qualifier.isSubClass(c, types)) {
1052 c = c.owner.enclClass();
1053 }
1054 return c;
1055 } else {
1056 while (!c.isSubClass(sym.owner, types)) {
1057 c = c.owner.enclClass();
1058 }
1059 }
1060 return c;
1061 } else {
1062 // the symbol is private
1063 return sym.owner.enclClass();
1064 }
1065 }
1066
1067 private boolean noClassDefIn(JCTree tree) {
1068 var scanner = new TreeScanner() {
1069 boolean noClassDef = true;
1070 @Override
1071 public void visitClassDef(JCClassDecl tree) {
1072 noClassDef = false;
1073 }
1074 };
1075 scanner.scan(tree);
1076 return scanner.noClassDef;
1077 }
1078
1079 private void addPrunedInfo(JCTree tree) {
1080 List<JCTree> infoList = prunedTree.get(currentClass);
1081 infoList = (infoList == null) ? List.of(tree) : infoList.prepend(tree);
1082 prunedTree.put(currentClass, infoList);
1083 }
1084
1085 /** Ensure that identifier is accessible, return tree accessing the identifier.
1086 * @param sym The accessed symbol.
1087 * @param tree The tree referring to the symbol.
1088 * @param enclOp The closest enclosing operation node of tree,
1089 * null if tree is not a subtree of an operation.
1090 * @param refSuper Is access via a (qualified) C.super?
1091 */
1092 JCExpression access(Symbol sym, JCExpression tree, JCExpression enclOp, boolean refSuper) {
1093 // Access a free variable via its proxy, or its proxy's proxy
1094 while (sym.kind == VAR && sym.owner.kind == MTH &&
1095 sym.owner.enclClass() != currentClass) {
1096 // A constant is replaced by its constant value.
1097 Object cv = ((VarSymbol)sym).getConstValue();
1098 if (cv != null) {
1099 make.at(tree.pos);
1100 return makeLit(sym.type, cv);
1101 }
1102 // Otherwise replace the variable by its proxy.
1103 sym = proxies.get(sym);
1104 Assert.check(sym != null && (sym.flags_field & FINAL) != 0);
1105 tree = make.at(tree.pos).Ident(sym);
1106 }
1107 JCExpression base = (tree.hasTag(SELECT)) ? ((JCFieldAccess) tree).selected : null;
1108 switch (sym.kind) {
1109 case TYP:
1110 if (sym.owner.kind != PCK) {
1111 // Convert type idents to
1112 // <flat name> or <package name> . <flat name>
1113 Name flatname = Convert.shortName(sym.flatName());
1114 while (base != null &&
1115 TreeInfo.symbol(base) != null &&
1116 TreeInfo.symbol(base).kind != PCK) {
1117 base = (base.hasTag(SELECT))
1118 ? ((JCFieldAccess) base).selected
1119 : null;
1120 }
1121 if (tree.hasTag(IDENT)) {
1122 ((JCIdent) tree).name = flatname;
1123 } else if (base == null) {
1124 tree = make.at(tree.pos).Ident(sym);
1125 ((JCIdent) tree).name = flatname;
1126 } else {
1127 ((JCFieldAccess) tree).selected = base;
1128 ((JCFieldAccess) tree).name = flatname;
1129 }
1130 }
1131 break;
1132 case MTH: case VAR:
1133 if (sym.owner.kind == TYP) {
1134
1135 // Access methods are required for
1136 // - private members,
1137 // - protected members in a superclass of an
1138 // enclosing class contained in another package.
1139 // - all non-private members accessed via a qualified super.
1140 boolean protAccess = refSuper && !needsPrivateAccess(sym)
1141 || needsProtectedAccess(sym, tree);
1142 boolean accReq = protAccess || needsPrivateAccess(sym);
1143
1144 // A base has to be supplied for
1145 // - simple identifiers accessing variables in outer classes.
1146 boolean baseReq =
1147 base == null &&
1148 sym.owner != syms.predefClass &&
1149 !sym.isMemberOf(currentClass, types);
1150
1151 if (accReq || baseReq) {
1152 make.at(tree.pos);
1153
1154 // Constants are replaced by their constant value.
1155 if (sym.kind == VAR) {
1156 Object cv = ((VarSymbol)sym).getConstValue();
1157 if (cv != null) {
1158 addPrunedInfo(tree);
1159 return makeLit(sym.type, cv);
1160 }
1161 }
1162
1163 // Private variables and methods are replaced by calls
1164 // to their access methods.
1165 if (accReq) {
1166 List<JCExpression> args = List.nil();
1167 if ((sym.flags() & STATIC) == 0) {
1168 // Instance access methods get instance
1169 // as first parameter.
1170 if (base == null)
1171 base = makeOwnerThis(tree.pos(), sym, true);
1172 args = args.prepend(base);
1173 base = null; // so we don't duplicate code
1174 }
1175 Symbol access = accessSymbol(sym, tree,
1176 enclOp, protAccess,
1177 refSuper);
1178 JCExpression receiver = make.Select(
1179 base != null ? base : make.QualIdent(access.owner),
1180 access);
1181 return make.App(receiver, args);
1182
1183 // Other accesses to members of outer classes get a
1184 // qualifier.
1185 } else if (baseReq) {
1186 return make.at(tree.pos).Select(
1187 accessBase(tree.pos(), sym), sym).setType(tree.type);
1188 }
1189 }
1190 }
1191 }
1192 return tree;
1193 }
1194
1195 /** Ensure that identifier is accessible, return tree accessing the identifier.
1196 * @param tree The identifier tree.
1197 */
1198 JCExpression access(JCExpression tree) {
1199 Symbol sym = TreeInfo.symbol(tree);
1200 return sym == null ? tree : access(sym, tree, null, false);
1201 }
1202
1203 /** Return access constructor for a private constructor,
1204 * or the constructor itself, if no access constructor is needed.
1205 * @param pos The position to report diagnostics, if any.
1206 * @param constr The private constructor.
1207 */
1208 Symbol accessConstructor(DiagnosticPosition pos, Symbol constr) {
1209 if (needsPrivateAccess(constr)) {
1210 ClassSymbol accOwner = constr.owner.enclClass();
1211 MethodSymbol aconstr = accessConstrs.get(constr);
1212 if (aconstr == null) {
1213 List<Type> argtypes = constr.type.getParameterTypes();
1214 if ((accOwner.flags_field & ENUM) != 0)
1215 argtypes = argtypes
1216 .prepend(syms.intType)
1217 .prepend(syms.stringType);
1218 aconstr = new MethodSymbol(
1219 SYNTHETIC,
1220 names.init,
1221 new MethodType(
1222 argtypes.append(
1223 accessConstructorTag().erasure(types)),
1224 constr.type.getReturnType(),
1225 constr.type.getThrownTypes(),
1226 syms.methodClass),
1227 accOwner);
1228 enterSynthetic(pos, aconstr, accOwner.members());
1229 accessConstrs.put(constr, aconstr);
1230 accessed.append(constr);
1231 }
1232 return aconstr;
1233 } else {
1234 return constr;
1235 }
1236 }
1237
1238 /** Return an anonymous class nested in this toplevel class.
1239 */
1240 ClassSymbol accessConstructorTag() {
1241 ClassSymbol topClass = currentClass.outermostClass();
1242 ModuleSymbol topModle = topClass.packge().modle;
1243 for (int i = 1; ; i++) {
1244 Name flatname = names.fromString("" + topClass.getQualifiedName() +
1245 target.syntheticNameChar() +
1246 i);
1247 ClassSymbol ctag = chk.getCompiled(topModle, flatname);
1248 if (ctag == null)
1249 ctag = makeEmptyClass(STATIC | SYNTHETIC, topClass).sym;
1250 else if (!ctag.isAnonymous())
1251 continue;
1252 // keep a record of all tags, to verify that all are generated as required
1253 accessConstrTags = accessConstrTags.prepend(ctag);
1254 return ctag;
1255 }
1256 }
1257
1258 /** Add all required access methods for a private symbol to enclosing class.
1259 * @param sym The symbol.
1260 */
1261 void makeAccessible(Symbol sym) {
1262 JCClassDecl cdef = classDef(sym.owner.enclClass());
1263 if (cdef == null) Assert.error("class def not found: " + sym + " in " + sym.owner);
1264 if (sym.name == names.init) {
1265 cdef.defs = cdef.defs.prepend(
1266 accessConstructorDef(cdef.pos, sym, accessConstrs.get(sym)));
1267 } else {
1268 MethodSymbol[] accessors = accessSyms.get(sym);
1269 for (int i = 0; i < AccessCode.numberOfAccessCodes; i++) {
1270 if (accessors[i] != null)
1271 cdef.defs = cdef.defs.prepend(
1272 accessDef(cdef.pos, sym, accessors[i], i));
1273 }
1274 }
1275 }
1276
1277 /** Construct definition of an access method.
1278 * @param pos The source code position of the definition.
1279 * @param vsym The private or protected symbol.
1280 * @param accessor The access method for the symbol.
1281 * @param acode The access code.
1282 */
1283 JCTree accessDef(int pos, Symbol vsym, MethodSymbol accessor, int acode) {
1284 // System.err.println("access " + vsym + " with " + accessor);//DEBUG
1285 currentClass = vsym.owner.enclClass();
1286 make.at(pos);
1287 JCMethodDecl md = make.MethodDef(accessor, null);
1288
1289 // Find actual symbol
1290 Symbol sym = actualSymbols.get(vsym);
1291 if (sym == null) sym = vsym;
1292
1293 JCExpression ref; // The tree referencing the private symbol.
1294 List<JCExpression> args; // Any additional arguments to be passed along.
1295 if ((sym.flags() & STATIC) != 0) {
1296 ref = make.Ident(sym);
1297 args = make.Idents(md.params);
1298 } else {
1299 JCExpression site = make.Ident(md.params.head);
1300 if (acode % 2 != 0) {
1301 //odd access codes represent qualified super accesses - need to
1302 //emit reference to the direct superclass, even if the referred
1303 //member is from an indirect superclass (JLS 13.1)
1304 site.setType(types.erasure(types.supertype(vsym.owner.enclClass().type)));
1305 }
1306 ref = make.Select(site, sym);
1307 args = make.Idents(md.params.tail);
1308 }
1309 JCStatement stat; // The statement accessing the private symbol.
1310 if (sym.kind == VAR) {
1311 // Normalize out all odd access codes by taking floor modulo 2:
1312 int acode1 = acode - (acode & 1);
1313
1314 JCExpression expr; // The access method's return value.
1315 AccessCode aCode = AccessCode.getFromCode(acode1);
1316 switch (aCode) {
1317 case DEREF:
1318 expr = ref;
1319 break;
1320 case ASSIGN:
1321 expr = make.Assign(ref, args.head);
1322 break;
1323 case PREINC: case POSTINC: case PREDEC: case POSTDEC:
1324 expr = makeUnary(aCode.tag, ref);
1325 break;
1326 default:
1327 expr = make.Assignop(
1328 treeTag(binaryAccessOperator(acode1, JCTree.Tag.NO_TAG)), ref, args.head);
1329 ((JCAssignOp) expr).operator = binaryAccessOperator(acode1, JCTree.Tag.NO_TAG);
1330 }
1331 stat = make.Return(expr.setType(sym.type));
1332 } else {
1333 stat = make.Call(make.App(ref, args));
1334 }
1335 md.body = make.Block(0, List.of(stat));
1336
1337 // Make sure all parameters, result types and thrown exceptions
1338 // are accessible.
1339 for (List<JCVariableDecl> l = md.params; l.nonEmpty(); l = l.tail)
1340 l.head.vartype = access(l.head.vartype);
1341 md.restype = access(md.restype);
1342 for (List<JCExpression> l = md.thrown; l.nonEmpty(); l = l.tail)
1343 l.head = access(l.head);
1344
1345 return md;
1346 }
1347
1348 /** Construct definition of an access constructor.
1349 * @param pos The source code position of the definition.
1350 * @param constr The private constructor.
1351 * @param accessor The access method for the constructor.
1352 */
1353 JCTree accessConstructorDef(int pos, Symbol constr, MethodSymbol accessor) {
1354 make.at(pos);
1355 JCMethodDecl md = make.MethodDef(accessor,
1356 accessor.externalType(types),
1357 null);
1358 JCIdent callee = make.Ident(names._this);
1359 callee.sym = constr;
1360 callee.type = constr.type;
1361 md.body =
1362 make.Block(0, List.of(
1363 make.Call(
1364 make.App(
1365 callee,
1366 make.Idents(md.params.reverse().tail.reverse())))));
1367 return md;
1368 }
1369
1370 /* ************************************************************************
1371 * Free variables proxies and this$n
1372 *************************************************************************/
1373
1374 /** A map which allows to retrieve the translated proxy variable for any given symbol of an
1375 * enclosing scope that is accessed (the accessed symbol could be the synthetic 'this$n' symbol).
1376 * Inside a constructor, the map temporarily overrides entries corresponding to proxies and any
1377 * 'this$n' symbols, where they represent the constructor parameters.
1378 */
1379 Map<Symbol, Symbol> proxies;
1380
1381 /** A scope containing all unnamed resource variables/saved
1382 * exception variables for translated TWR blocks
1383 */
1384 WriteableScope twrVars;
1385
1386 /** A stack containing the this$n field of the currently translated
1387 * classes (if needed) in innermost first order.
1388 * Inside a constructor, proxies and any this$n symbol are duplicated
1389 * in an additional innermost scope, where they represent the constructor
1390 * parameters.
1391 */
1392 List<VarSymbol> outerThisStack;
1393
1394 /** The name of a free variable proxy.
1395 */
1396 Name proxyName(Name name, int index) {
1397 Name proxyName = names.fromString("val" + target.syntheticNameChar() + name);
1398 if (index > 0) {
1399 proxyName = proxyName.append(names.fromString("" + target.syntheticNameChar() + index));
1400 }
1401 return proxyName;
1402 }
1403
1404 /** Proxy definitions for all free variables in given list, in reverse order.
1405 * @param pos The source code position of the definition.
1406 * @param freevars The free variables.
1407 * @param owner The class in which the definitions go.
1408 */
1409 List<JCVariableDecl> freevarDefs(int pos, List<VarSymbol> freevars, Symbol owner) {
1410 return freevarDefs(pos, freevars, owner, LOCAL_CAPTURE_FIELD);
1411 }
1412
1413 List<JCVariableDecl> freevarDefs(int pos, List<VarSymbol> freevars, Symbol owner,
1414 long additionalFlags) {
1415 long flags = FINAL | SYNTHETIC | additionalFlags;
1416 List<JCVariableDecl> defs = List.nil();
1417 Set<Name> proxyNames = new HashSet<>();
1418 for (List<VarSymbol> l = freevars; l.nonEmpty(); l = l.tail) {
1419 VarSymbol v = l.head;
1420 int index = 0;
1421 Name proxyName;
1422 do {
1423 proxyName = proxyName(v.name, index++);
1424 } while (!proxyNames.add(proxyName));
1425 VarSymbol proxy = new VarSymbol(
1426 flags, proxyName, v.erasure(types), owner) {
1427 @Override
1428 public Symbol baseSymbol() {
1429 return v;
1430 }
1431 };
1432 proxies.put(v, proxy);
1433 JCVariableDecl vd = make.at(pos).VarDef(proxy, null);
1434 vd.vartype = access(vd.vartype);
1435 defs = defs.prepend(vd);
1436 }
1437 return defs;
1438 }
1439
1440 /** The name of a this$n field
1441 * @param type The class referenced by the this$n field
1442 */
1443 Name outerThisName(Type type, Symbol owner) {
1444 Type t = type.getEnclosingType();
1445 int nestingLevel = 0;
1446 while (t.hasTag(CLASS)) {
1447 t = t.getEnclosingType();
1448 nestingLevel++;
1449 }
1450 Name result = names.fromString("this" + target.syntheticNameChar() + nestingLevel);
1451 while (owner.kind == TYP && ((ClassSymbol)owner).members().findFirst(result) != null)
1452 result = names.fromString(result.toString() + target.syntheticNameChar());
1453 return result;
1454 }
1455
1456 private VarSymbol makeOuterThisVarSymbol(Symbol owner, long flags) {
1457 Type target = owner.innermostAccessibleEnclosingClass().erasure(types);
1458 // Set NOOUTERTHIS for all synthetic outer instance variables, and unset
1459 // it when the variable is accessed. If the variable is never accessed,
1460 // we skip creating an outer instance field and saving the constructor
1461 // parameter to it.
1462 VarSymbol outerThis =
1463 new VarSymbol(flags | NOOUTERTHIS, outerThisName(target, owner), target, owner);
1464 outerThisStack = outerThisStack.prepend(outerThis);
1465 return outerThis;
1466 }
1467
1468 private JCVariableDecl makeOuterThisVarDecl(int pos, VarSymbol sym) {
1469 JCVariableDecl vd = make.at(pos).VarDef(sym, null);
1470 vd.vartype = access(vd.vartype);
1471 return vd;
1472 }
1473
1474 /** Definition for this$n field.
1475 * @param pos The source code position of the definition.
1476 * @param owner The method in which the definition goes.
1477 */
1478 JCVariableDecl outerThisDef(int pos, MethodSymbol owner) {
1479 ClassSymbol c = owner.enclClass();
1480 boolean isMandated =
1481 // Anonymous constructors
1482 (owner.isConstructor() && owner.isAnonymous()) ||
1483 // Constructors of non-private inner member classes
1484 (owner.isConstructor() && c.isInner() &&
1485 !c.isPrivate() && !c.isStatic());
1486 long flags =
1487 FINAL | (isMandated ? MANDATED : SYNTHETIC) | PARAMETER;
1488 VarSymbol outerThis = makeOuterThisVarSymbol(owner, flags);
1489 owner.extraParams = owner.extraParams.prepend(outerThis);
1490 return makeOuterThisVarDecl(pos, outerThis);
1491 }
1492
1493 /** Definition for this$n field.
1494 * @param pos The source code position of the definition.
1495 * @param owner The class in which the definition goes.
1496 */
1497 JCVariableDecl outerThisDef(int pos, ClassSymbol owner) {
1498 VarSymbol outerThis = makeOuterThisVarSymbol(owner, FINAL | SYNTHETIC);
1499 return makeOuterThisVarDecl(pos, outerThis);
1500 }
1501
1502 /** Return a list of trees that load the free variables in given list,
1503 * in reverse order.
1504 * @param pos The source code position to be used for the trees.
1505 * @param freevars The list of free variables.
1506 */
1507 List<JCExpression> loadFreevars(DiagnosticPosition pos, List<VarSymbol> freevars) {
1508 List<JCExpression> args = List.nil();
1509 for (List<VarSymbol> l = freevars; l.nonEmpty(); l = l.tail)
1510 args = args.prepend(loadFreevar(pos, l.head));
1511 return args;
1512 }
1513 //where
1514 JCExpression loadFreevar(DiagnosticPosition pos, VarSymbol v) {
1515 return access(v, make.at(pos).Ident(v), null, false);
1516 }
1517
1518 /** Construct a tree simulating the expression {@code C.this}.
1519 * @param pos The source code position to be used for the tree.
1520 * @param c The qualifier class.
1521 */
1522 JCExpression makeThis(DiagnosticPosition pos, TypeSymbol c) {
1523 if (currentClass == c) {
1524 // in this case, `this' works fine
1525 return make.at(pos).This(c.erasure(types));
1526 } else {
1527 // need to go via this$n
1528 return makeOuterThis(pos, c);
1529 }
1530 }
1531
1532 /**
1533 * Optionally replace a try statement with the desugaring of a
1534 * try-with-resources statement. The canonical desugaring of
1535 *
1536 * try ResourceSpecification
1537 * Block
1538 *
1539 * is
1540 *
1541 * {
1542 * final VariableModifiers_minus_final R #resource = Expression;
1543 *
1544 * try ResourceSpecificationtail
1545 * Block
1546 * } body-only-finally {
1547 * if (#resource != null) //nullcheck skipped if Expression is provably non-null
1548 * #resource.close();
1549 * } catch (Throwable #primaryException) {
1550 * if (#resource != null) //nullcheck skipped if Expression is provably non-null
1551 * try {
1552 * #resource.close();
1553 * } catch (Throwable #suppressedException) {
1554 * #primaryException.addSuppressed(#suppressedException);
1555 * }
1556 * throw #primaryException;
1557 * }
1558 * }
1559 *
1560 * @param tree The try statement to inspect.
1561 * @return a desugared try-with-resources tree, or the original
1562 * try block if there are no resources to manage.
1563 */
1564 JCTree makeTwrTry(JCTry tree) {
1565 make_at(tree.pos());
1566 twrVars = twrVars.dup();
1567 JCBlock twrBlock = makeTwrBlock(tree.resources, tree.body, 0);
1568 if (tree.catchers.isEmpty() && tree.finalizer == null)
1569 result = translate(twrBlock);
1570 else
1571 result = translate(make.Try(twrBlock, tree.catchers, tree.finalizer));
1572 twrVars = twrVars.leave();
1573 return result;
1574 }
1575
1576 private JCBlock makeTwrBlock(List<JCTree> resources, JCBlock block, int depth) {
1577 if (resources.isEmpty())
1578 return block;
1579
1580 // Add resource declaration or expression to block statements
1581 ListBuffer<JCStatement> stats = new ListBuffer<>();
1582 JCTree resource = resources.head;
1583 JCExpression resourceUse;
1584 boolean resourceNonNull;
1585 if (resource instanceof JCVariableDecl variableDecl) {
1586 resourceUse = make.Ident(variableDecl.sym).setType(resource.type);
1587 resourceNonNull = variableDecl.init != null && TreeInfo.skipParens(variableDecl.init).hasTag(NEWCLASS);
1588 stats.add(variableDecl);
1589 } else {
1590 Assert.check(resource instanceof JCExpression);
1591 VarSymbol syntheticTwrVar =
1592 new VarSymbol(SYNTHETIC | FINAL,
1593 makeSyntheticName(names.fromString("twrVar" +
1594 depth), twrVars),
1595 (resource.type.hasTag(BOT)) ?
1596 syms.autoCloseableType : resource.type,
1597 currentMethodSym);
1598 twrVars.enter(syntheticTwrVar);
1599 JCVariableDecl syntheticTwrVarDecl =
1600 make.VarDef(syntheticTwrVar, (JCExpression)resource);
1601 resourceUse = (JCExpression)make.Ident(syntheticTwrVar);
1602 resourceNonNull = false;
1603 stats.add(syntheticTwrVarDecl);
1604 }
1605
1606 //create (semi-) finally block that will be copied into the main try body:
1607 int oldPos = make.pos;
1608 make.at(TreeInfo.endPos(block));
1609
1610 // if (#resource != null) { #resource.close(); }
1611 JCStatement bodyCloseStatement = makeResourceCloseInvocation(resourceUse);
1612
1613 if (!resourceNonNull) {
1614 bodyCloseStatement = make.If(makeNonNullCheck(resourceUse),
1615 bodyCloseStatement,
1616 null);
1617 }
1618
1619 JCBlock finallyClause = make.Block(BODY_ONLY_FINALIZE, List.of(bodyCloseStatement));
1620 make.at(oldPos);
1621
1622 // Create catch clause that saves exception, closes the resource and then rethrows the exception:
1623 VarSymbol primaryException =
1624 new VarSymbol(FINAL|SYNTHETIC,
1625 names.fromString("t" +
1626 target.syntheticNameChar()),
1627 syms.throwableType,
1628 currentMethodSym);
1629 JCVariableDecl primaryExceptionDecl = make.VarDef(primaryException, null);
1630
1631 // close resource:
1632 // try {
1633 // #resource.close();
1634 // } catch (Throwable #suppressedException) {
1635 // #primaryException.addSuppressed(#suppressedException);
1636 // }
1637 VarSymbol suppressedException =
1638 new VarSymbol(SYNTHETIC, make.paramName(2),
1639 syms.throwableType,
1640 currentMethodSym);
1641 JCStatement addSuppressedStatement =
1642 make.Exec(makeCall(make.Ident(primaryException),
1643 names.addSuppressed,
1644 List.of(make.Ident(suppressedException))));
1645 JCBlock closeResourceTryBlock =
1646 make.Block(0L, List.of(makeResourceCloseInvocation(resourceUse)));
1647 JCVariableDecl catchSuppressedDecl = make.VarDef(suppressedException, null);
1648 JCBlock catchSuppressedBlock = make.Block(0L, List.of(addSuppressedStatement));
1649 List<JCCatch> catchSuppressedClauses =
1650 List.of(make.Catch(catchSuppressedDecl, catchSuppressedBlock));
1651 JCTry closeResourceTry = make.Try(closeResourceTryBlock, catchSuppressedClauses, null);
1652 closeResourceTry.finallyCanCompleteNormally = true;
1653
1654 JCStatement exceptionalCloseStatement = closeResourceTry;
1655
1656 if (!resourceNonNull) {
1657 // if (#resource != null) { }
1658 exceptionalCloseStatement = make.If(makeNonNullCheck(resourceUse),
1659 exceptionalCloseStatement,
1660 null);
1661 }
1662
1663 JCStatement exceptionalRethrow = make.Throw(make.Ident(primaryException));
1664 JCBlock exceptionalCloseBlock = make.Block(0L, List.of(exceptionalCloseStatement, exceptionalRethrow));
1665 JCCatch exceptionalCatchClause = make.Catch(primaryExceptionDecl, exceptionalCloseBlock);
1666
1667 //create the main try statement with the close:
1668 JCTry outerTry = make.Try(makeTwrBlock(resources.tail, block, depth + 1),
1669 List.of(exceptionalCatchClause),
1670 finallyClause);
1671
1672 outerTry.finallyCanCompleteNormally = true;
1673 stats.add(outerTry);
1674
1675 JCBlock newBlock = make.Block(0L, stats.toList());
1676 return newBlock;
1677 }
1678
1679 private JCStatement makeResourceCloseInvocation(JCExpression resource) {
1680 // convert to AutoCloseable if needed
1681 if (types.asSuper(resource.type, syms.autoCloseableType.tsym) == null) {
1682 resource = convert(resource, syms.autoCloseableType);
1683 }
1684
1685 // create resource.close() method invocation
1686 JCExpression resourceClose = makeCall(resource,
1687 names.close,
1688 List.nil());
1689 return make.Exec(resourceClose);
1690 }
1691
1692 private JCExpression makeNonNullCheck(JCExpression expression) {
1693 return makeBinary(NE, expression, makeNull());
1694 }
1695
1696 /** Construct a tree that represents the outer instance
1697 * {@code C.this}. Never pick the current `this'.
1698 * @param pos The source code position to be used for the tree.
1699 * @param c The qualifier class.
1700 */
1701 JCExpression makeOuterThis(DiagnosticPosition pos, TypeSymbol c) {
1702 List<VarSymbol> ots = outerThisStack;
1703 if (ots.isEmpty()) {
1704 log.error(pos, Errors.NoEnclInstanceOfTypeInScope(c));
1705 return makeNull();
1706 }
1707 VarSymbol ot = ots.head;
1708 JCExpression tree = access(make.at(pos).Ident(ot));
1709 ot.flags_field &= ~NOOUTERTHIS;
1710 TypeSymbol otc = ot.type.tsym;
1711 while (otc != c) {
1712 do {
1713 ots = ots.tail;
1714 if (ots.isEmpty()) {
1715 log.error(pos, Errors.NoEnclInstanceOfTypeInScope(c));
1716 Assert.error(); // should have been caught in Attr
1717 return tree;
1718 }
1719 ot = ots.head;
1720 } while (ot.owner != otc);
1721 if (otc.owner.kind != PCK && !otc.hasOuterInstance()) {
1722 log.error(pos, Errors.NoEnclInstanceOfTypeInScope(c));
1723 Assert.error(); // should have been caught in Attr
1724 return makeNull();
1725 }
1726 tree = access(make.at(pos).Select(tree, ot));
1727 ot.flags_field &= ~NOOUTERTHIS;
1728 otc = ot.type.tsym;
1729 }
1730 return tree;
1731 }
1732
1733 /** Construct a tree that represents the closest outer instance
1734 * {@code C.this} such that the given symbol is a member of C.
1735 * @param pos The source code position to be used for the tree.
1736 * @param sym The accessed symbol.
1737 * @param preciseMatch should we accept a type that is a subtype of
1738 * sym's owner, even if it doesn't contain sym
1739 * due to hiding, overriding, or non-inheritance
1740 * due to protection?
1741 */
1742 JCExpression makeOwnerThis(DiagnosticPosition pos, Symbol sym, boolean preciseMatch) {
1743 if (preciseMatch ? sym.isMemberOf(currentClass, types)
1744 : currentClass.isSubClass(sym.owner, types)) {
1745 // in this case, `this' works fine
1746 return make.at(pos).This(currentClass.erasure(types));
1747 } else {
1748 // need to go via this$n
1749 return makeOwnerThisN(pos, sym, preciseMatch);
1750 }
1751 }
1752
1753 /**
1754 * Similar to makeOwnerThis but will never pick "this".
1755 */
1756 JCExpression makeOwnerThisN(DiagnosticPosition pos, Symbol sym, boolean preciseMatch) {
1757 Symbol c = sym.owner;
1758 List<VarSymbol> ots = outerThisStack;
1759 if (ots.isEmpty()) {
1760 log.error(pos, Errors.NoEnclInstanceOfTypeInScope(c));
1761 return makeNull();
1762 }
1763 VarSymbol ot = ots.head;
1764 JCExpression tree = access(make.at(pos).Ident(ot));
1765 ot.flags_field &= ~NOOUTERTHIS;
1766 TypeSymbol otc = ot.type.tsym;
1767 while (!(preciseMatch ? sym.isMemberOf(otc, types) : otc.isSubClass(sym.owner, types))) {
1768 do {
1769 ots = ots.tail;
1770 if (ots.isEmpty()) {
1771 log.error(pos, Errors.NoEnclInstanceOfTypeInScope(c));
1772 return tree;
1773 }
1774 ot = ots.head;
1775 } while (ot.owner != otc);
1776 tree = access(make.at(pos).Select(tree, ot));
1777 ot.flags_field &= ~NOOUTERTHIS;
1778 otc = ot.type.tsym;
1779 }
1780 return tree;
1781 }
1782
1783 /** Return tree simulating the assignment {@code this.name = name}, where
1784 * name is the name of a free variable.
1785 */
1786 JCStatement initField(int pos, Symbol rhs, Symbol lhs) {
1787 Assert.check(rhs.owner.kind == MTH);
1788 Assert.check(rhs.owner.owner == lhs.owner);
1789 make.at(pos);
1790 return
1791 make.Exec(
1792 make.Assign(
1793 make.Select(make.This(lhs.owner.erasure(types)), lhs),
1794 make.Ident(rhs)).setType(lhs.erasure(types)));
1795 }
1796
1797 /** Return tree simulating the assignment {@code this.this$n = this$n}.
1798 */
1799 JCStatement initOuterThis(int pos, VarSymbol rhs) {
1800 Assert.check(rhs.owner.kind == MTH);
1801 VarSymbol lhs = outerThisStack.head;
1802 Assert.check(rhs.owner.owner == lhs.owner);
1803 make.at(pos);
1804 return
1805 make.Exec(
1806 make.Assign(
1807 make.Select(make.This(lhs.owner.erasure(types)), lhs),
1808 make.Ident(rhs)).setType(lhs.erasure(types)));
1809 }
1810
1811 /* ************************************************************************
1812 * Code for .class
1813 *************************************************************************/
1814
1815 /** Return the symbol of a class to contain a cache of
1816 * compiler-generated statics such as class$ and the
1817 * $assertionsDisabled flag. We create an anonymous nested class
1818 * (unless one already exists) and return its symbol. However,
1819 * for backward compatibility in 1.4 and earlier we use the
1820 * top-level class itself.
1821 */
1822 private ClassSymbol outerCacheClass() {
1823 ClassSymbol clazz = outermostClassDef.sym;
1824 Scope s = clazz.members();
1825 for (Symbol sym : s.getSymbols(NON_RECURSIVE))
1826 if (sym.kind == TYP &&
1827 sym.name == names.empty &&
1828 (sym.flags() & INTERFACE) == 0) return (ClassSymbol) sym;
1829 return makeEmptyClass(STATIC | SYNTHETIC, clazz).sym;
1830 }
1831
1832 /** Create an attributed tree of the form left.name(). */
1833 private JCMethodInvocation makeCall(JCExpression left, Name name, List<JCExpression> args) {
1834 Assert.checkNonNull(left.type);
1835 Symbol funcsym = lookupMethod(make_pos, name, left.type,
1836 TreeInfo.types(args));
1837 return make.App(make.Select(left, funcsym), args);
1838 }
1839
1840 /** The tree simulating a T.class expression.
1841 * @param clazz The tree identifying type T.
1842 */
1843 private JCExpression classOf(JCTree clazz) {
1844 return classOfType(clazz.type, clazz.pos());
1845 }
1846
1847 private JCExpression classOfType(Type type, DiagnosticPosition pos) {
1848 switch (type.getTag()) {
1849 case BYTE: case SHORT: case CHAR: case INT: case LONG: case FLOAT:
1850 case DOUBLE: case BOOLEAN: case VOID:
1851 // replace with <BoxedClass>.TYPE
1852 ClassSymbol c = types.boxedClass(type);
1853 Symbol typeSym =
1854 rs.accessBase(
1855 rs.findIdentInType(pos, attrEnv, c.type, names.TYPE, KindSelector.VAR),
1856 pos, c.type, names.TYPE, true);
1857 if (typeSym.kind == VAR)
1858 ((VarSymbol)typeSym).getConstValue(); // ensure initializer is evaluated
1859 return make.QualIdent(typeSym);
1860 case CLASS: case ARRAY:
1861 VarSymbol sym = new VarSymbol(
1862 STATIC | PUBLIC | FINAL, names._class,
1863 syms.classType, type.tsym);
1864 return make_at(pos).Select(make.Type(type), sym);
1865 default:
1866 throw new AssertionError();
1867 }
1868 }
1869
1870 /* ************************************************************************
1871 * Code for enabling/disabling assertions.
1872 *************************************************************************/
1873
1874 private ClassSymbol assertionsDisabledClassCache;
1875
1876 /**Used to create an auxiliary class to hold $assertionsDisabled for interfaces.
1877 */
1878 private ClassSymbol assertionsDisabledClass() {
1879 if (assertionsDisabledClassCache != null) return assertionsDisabledClassCache;
1880
1881 assertionsDisabledClassCache = makeEmptyClass(STATIC | SYNTHETIC, outermostClassDef.sym).sym;
1882
1883 return assertionsDisabledClassCache;
1884 }
1885
1886 // This code is not particularly robust if the user has
1887 // previously declared a member named '$assertionsDisabled'.
1888 // The same faulty idiom also appears in the translation of
1889 // class literals above. We should report an error if a
1890 // previous declaration is not synthetic.
1891
1892 private JCExpression assertFlagTest(DiagnosticPosition pos) {
1893 // Outermost class may be either true class or an interface.
1894 ClassSymbol outermostClass = outermostClassDef.sym;
1895
1896 //only classes can hold a non-public field, look for a usable one:
1897 ClassSymbol container = !currentClass.isInterface() ? currentClass :
1898 assertionsDisabledClass();
1899
1900 VarSymbol assertDisabledSym =
1901 (VarSymbol)lookupSynthetic(dollarAssertionsDisabled,
1902 container.members());
1903 if (assertDisabledSym == null) {
1904 assertDisabledSym =
1905 new VarSymbol(STATIC | FINAL | SYNTHETIC,
1906 dollarAssertionsDisabled,
1907 syms.booleanType,
1908 container);
1909 enterSynthetic(pos, assertDisabledSym, container.members());
1910 Symbol desiredAssertionStatusSym = lookupMethod(pos,
1911 names.desiredAssertionStatus,
1912 types.erasure(syms.classType),
1913 List.nil());
1914 JCClassDecl containerDef = classDef(container);
1915 make_at(containerDef.pos());
1916 JCExpression notStatus = makeUnary(NOT, make.App(make.Select(
1917 classOfType(types.erasure(outermostClass.type),
1918 containerDef.pos()),
1919 desiredAssertionStatusSym)));
1920 JCVariableDecl assertDisabledDef = make.VarDef(assertDisabledSym,
1921 notStatus);
1922 containerDef.defs = containerDef.defs.prepend(assertDisabledDef);
1923
1924 if (currentClass.isInterface()) {
1925 //need to load the assertions enabled/disabled state while
1926 //initializing the interface:
1927 JCClassDecl currentClassDef = classDef(currentClass);
1928 make_at(currentClassDef.pos());
1929 JCStatement dummy = make.If(make.QualIdent(assertDisabledSym), make.Skip(), null);
1930 JCBlock clinit = make.Block(STATIC, List.of(dummy));
1931 currentClassDef.defs = currentClassDef.defs.prepend(clinit);
1932 }
1933 }
1934 make_at(pos);
1935 return makeUnary(NOT, make.Ident(assertDisabledSym));
1936 }
1937
1938
1939 /* ************************************************************************
1940 * Building blocks for let expressions
1941 *************************************************************************/
1942
1943 interface TreeBuilder {
1944 JCExpression build(JCExpression arg);
1945 }
1946
1947 /** Construct an expression using the builder, with the given rval
1948 * expression as an argument to the builder. However, the rval
1949 * expression must be computed only once, even if used multiple
1950 * times in the result of the builder. We do that by
1951 * constructing a "let" expression that saves the rvalue into a
1952 * temporary variable and then uses the temporary variable in
1953 * place of the expression built by the builder. The complete
1954 * resulting expression is of the form
1955 * <pre>
1956 * (let <b>TYPE</b> <b>TEMP</b> = <b>RVAL</b>;
1957 * in (<b>BUILDER</b>(<b>TEMP</b>)))
1958 * </pre>
1959 * where <code><b>TEMP</b></code> is a newly declared variable
1960 * in the let expression.
1961 */
1962 JCExpression abstractRval(JCExpression rval, Type type, TreeBuilder builder) {
1963 rval = TreeInfo.skipParens(rval);
1964 switch (rval.getTag()) {
1965 case LITERAL:
1966 return builder.build(rval);
1967 case IDENT:
1968 JCIdent id = (JCIdent) rval;
1969 if ((id.sym.flags() & FINAL) != 0 && id.sym.owner.kind == MTH)
1970 return builder.build(rval);
1971 }
1972 Name name = TreeInfo.name(rval);
1973 if (name == names._super || name == names._this)
1974 return builder.build(rval);
1975 VarSymbol var =
1976 new VarSymbol(FINAL|SYNTHETIC,
1977 names.fromString(
1978 target.syntheticNameChar()
1979 + "" + rval.hashCode()),
1980 type,
1981 currentMethodSym);
1982 rval = convert(rval,type);
1983 JCVariableDecl def = make.VarDef(var, rval); // XXX cast
1984 JCExpression built = builder.build(make.Ident(var));
1985 JCExpression res = make.LetExpr(def, built);
1986 res.type = built.type;
1987 return res;
1988 }
1989
1990 // same as above, with the type of the temporary variable computed
1991 JCExpression abstractRval(JCExpression rval, TreeBuilder builder) {
1992 return abstractRval(rval, rval.type, builder);
1993 }
1994
1995 // same as above, but for an expression that may be used as either
1996 // an rvalue or an lvalue. This requires special handling for
1997 // Select expressions, where we place the left-hand-side of the
1998 // select in a temporary, and for Indexed expressions, where we
1999 // place both the indexed expression and the index value in temps.
2000 JCExpression abstractLval(JCExpression lval, final TreeBuilder builder) {
2001 lval = TreeInfo.skipParens(lval);
2002 switch (lval.getTag()) {
2003 case IDENT:
2004 return builder.build(lval);
2005 case SELECT: {
2006 final JCFieldAccess s = (JCFieldAccess)lval;
2007 Symbol lid = TreeInfo.symbol(s.selected);
2008 if (lid != null && lid.kind == TYP) return builder.build(lval);
2009 return abstractRval(s.selected, selected -> builder.build(make.Select(selected, s.sym)));
2010 }
2011 case INDEXED: {
2012 final JCArrayAccess i = (JCArrayAccess)lval;
2013 return abstractRval(i.indexed, indexed -> abstractRval(i.index, syms.intType, index -> {
2014 JCExpression newLval = make.Indexed(indexed, index);
2015 newLval.setType(i.type);
2016 return builder.build(newLval);
2017 }));
2018 }
2019 case TYPECAST: {
2020 return abstractLval(((JCTypeCast)lval).expr, builder);
2021 }
2022 }
2023 throw new AssertionError(lval);
2024 }
2025
2026 // evaluate and discard the first expression, then evaluate the second.
2027 JCExpression makeComma(final JCExpression expr1, final JCExpression expr2) {
2028 JCExpression res = make.LetExpr(List.of(make.Exec(expr1)), expr2);
2029 res.type = expr2.type;
2030 return res;
2031 }
2032
2033 /* ************************************************************************
2034 * Translation methods
2035 *************************************************************************/
2036
2037 /** Visitor argument: enclosing operator node.
2038 */
2039 private JCExpression enclOp;
2040
2041 /** Visitor method: Translate a single node.
2042 * Attach the source position from the old tree to its replacement tree.
2043 */
2044 @Override
2045 public <T extends JCTree> T translate(T tree) {
2046 if (tree == null) {
2047 return null;
2048 } else {
2049 make_at(tree.pos());
2050 T result = super.translate(tree);
2051 if (endPosTable != null && result != tree) {
2052 endPosTable.replaceTree(tree, result);
2053 }
2054 return result;
2055 }
2056 }
2057
2058 /** Visitor method: Translate a single node, boxing or unboxing if needed.
2059 */
2060 public <T extends JCExpression> T translate(T tree, Type type) {
2061 return (tree == null) ? null : boxIfNeeded(translate(tree), type);
2062 }
2063
2064 /** Visitor method: Translate tree.
2065 */
2066 public <T extends JCTree> T translate(T tree, JCExpression enclOp) {
2067 JCExpression prevEnclOp = this.enclOp;
2068 this.enclOp = enclOp;
2069 T res = translate(tree);
2070 this.enclOp = prevEnclOp;
2071 return res;
2072 }
2073
2074 /** Visitor method: Translate list of trees.
2075 */
2076 public <T extends JCExpression> List<T> translate(List<T> trees, Type type) {
2077 if (trees == null) return null;
2078 for (List<T> l = trees; l.nonEmpty(); l = l.tail)
2079 l.head = translate(l.head, type);
2080 return trees;
2081 }
2082
2083 public void visitPackageDef(JCPackageDecl tree) {
2084 if (!needPackageInfoClass(tree))
2085 return;
2086
2087 long flags = Flags.ABSTRACT | Flags.INTERFACE;
2088 // package-info is marked SYNTHETIC in JDK 1.6 and later releases
2089 flags = flags | Flags.SYNTHETIC;
2090 ClassSymbol c = tree.packge.package_info;
2091 c.setAttributes(tree.packge);
2092 c.flags_field |= flags;
2093 ClassType ctype = (ClassType) c.type;
2094 ctype.supertype_field = syms.objectType;
2095 ctype.interfaces_field = List.nil();
2096 createInfoClass(tree.annotations, c);
2097 }
2098 // where
2099 private boolean needPackageInfoClass(JCPackageDecl pd) {
2100 switch (pkginfoOpt) {
2101 case ALWAYS:
2102 return true;
2103 case LEGACY:
2104 return pd.getAnnotations().nonEmpty();
2105 case NONEMPTY:
2106 for (Attribute.Compound a :
2107 pd.packge.getDeclarationAttributes()) {
2108 Attribute.RetentionPolicy p = types.getRetention(a);
2109 if (p != Attribute.RetentionPolicy.SOURCE)
2110 return true;
2111 }
2112 return false;
2113 }
2114 throw new AssertionError();
2115 }
2116
2117 public void visitModuleDef(JCModuleDecl tree) {
2118 ModuleSymbol msym = tree.sym;
2119 ClassSymbol c = msym.module_info;
2120 c.setAttributes(msym);
2121 c.flags_field |= Flags.MODULE;
2122 createInfoClass(List.nil(), tree.sym.module_info);
2123 }
2124
2125 private void createInfoClass(List<JCAnnotation> annots, ClassSymbol c) {
2126 long flags = Flags.ABSTRACT | Flags.INTERFACE;
2127 JCClassDecl infoClass =
2128 make.ClassDef(make.Modifiers(flags, annots),
2129 c.name, List.nil(),
2130 null, List.nil(), List.nil());
2131 infoClass.sym = c;
2132 translated.append(infoClass);
2133 }
2134
2135 public void visitClassDef(JCClassDecl tree) {
2136 Env<AttrContext> prevEnv = attrEnv;
2137 ClassSymbol currentClassPrev = currentClass;
2138 MethodSymbol currentMethodSymPrev = currentMethodSym;
2139
2140 currentClass = tree.sym;
2141 currentMethodSym = null;
2142 attrEnv = typeEnvs.remove(currentClass);
2143 if (attrEnv == null)
2144 attrEnv = prevEnv;
2145
2146 classdefs.put(currentClass, tree);
2147
2148 Map<Symbol, Symbol> prevProxies = proxies;
2149 proxies = new HashMap<>(proxies);
2150 List<VarSymbol> prevOuterThisStack = outerThisStack;
2151
2152 // If this is an enum definition
2153 if ((tree.mods.flags & ENUM) != 0 &&
2154 (types.supertype(currentClass.type).tsym.flags() & ENUM) == 0)
2155 visitEnumDef(tree);
2156
2157 if ((tree.mods.flags & RECORD) != 0) {
2158 visitRecordDef(tree);
2159 }
2160
2161 // If this is a nested class, define a this$n field for
2162 // it and add to proxies.
2163 JCVariableDecl otdef = null;
2164 if (currentClass.hasOuterInstance())
2165 otdef = outerThisDef(tree.pos, currentClass);
2166
2167 // If this is a local class, define proxies for all its free variables.
2168 List<JCVariableDecl> fvdefs = freevarDefs(
2169 tree.pos, freevars(currentClass), currentClass);
2170
2171 // Recursively translate superclass, interfaces.
2172 tree.extending = translate(tree.extending);
2173 tree.implementing = translate(tree.implementing);
2174
2175 if (currentClass.isDirectlyOrIndirectlyLocal()) {
2176 ClassSymbol encl = currentClass.owner.enclClass();
2177 if (encl.trans_local == null) {
2178 encl.trans_local = List.nil();
2179 }
2180 encl.trans_local = encl.trans_local.prepend(currentClass);
2181 }
2182
2183 // Recursively translate members, taking into account that new members
2184 // might be created during the translation and prepended to the member
2185 // list `tree.defs'.
2186 List<JCTree> seen = List.nil();
2187 while (tree.defs != seen) {
2188 List<JCTree> unseen = tree.defs;
2189 for (List<JCTree> l = unseen; l.nonEmpty() && l != seen; l = l.tail) {
2190 JCTree outermostMemberDefPrev = outermostMemberDef;
2191 if (outermostMemberDefPrev == null) outermostMemberDef = l.head;
2192 l.head = translate(l.head);
2193 outermostMemberDef = outermostMemberDefPrev;
2194 }
2195 seen = unseen;
2196 }
2197
2198 // Convert a protected modifier to public, mask static modifier.
2199 if ((tree.mods.flags & PROTECTED) != 0) tree.mods.flags |= PUBLIC;
2200 tree.mods.flags &= ClassFlags;
2201
2202 // Convert name to flat representation, replacing '.' by '$'.
2203 tree.name = Convert.shortName(currentClass.flatName());
2204
2205 // Add free variables proxy definitions to class.
2206
2207 for (List<JCVariableDecl> l = fvdefs; l.nonEmpty(); l = l.tail) {
2208 tree.defs = tree.defs.prepend(l.head);
2209 enterSynthetic(tree.pos(), l.head.sym, currentClass.members());
2210 }
2211 // If this$n was accessed, add the field definition and prepend
2212 // initializer code to any super() invocation to initialize it
2213 if (currentClass.hasOuterInstance() && shouldEmitOuterThis(currentClass)) {
2214 tree.defs = tree.defs.prepend(otdef);
2215 enterSynthetic(tree.pos(), otdef.sym, currentClass.members());
2216
2217 for (JCTree def : tree.defs) {
2218 if (TreeInfo.isConstructor(def)) {
2219 JCMethodDecl mdef = (JCMethodDecl)def;
2220 if (TreeInfo.hasConstructorCall(mdef, names._super)) {
2221 List<JCStatement> initializer = List.of(initOuterThis(mdef.body.pos, mdef.params.head.sym));
2222 TreeInfo.mapSuperCalls(mdef.body, supercall -> make.Block(0, initializer.append(supercall)));
2223 }
2224 }
2225 }
2226 }
2227
2228 proxies = prevProxies;
2229 outerThisStack = prevOuterThisStack;
2230
2231 // Append translated tree to `translated' queue.
2232 translated.append(tree);
2233
2234 attrEnv = prevEnv;
2235 currentClass = currentClassPrev;
2236 currentMethodSym = currentMethodSymPrev;
2237
2238 // Return empty block {} as a placeholder for an inner class.
2239 result = make_at(tree.pos()).Block(SYNTHETIC, List.nil());
2240 }
2241
2242 private boolean shouldEmitOuterThis(ClassSymbol sym) {
2243 if (!optimizeOuterThis) {
2244 // Optimization is disabled
2245 return true;
2246 }
2247 if ((outerThisStack.head.flags_field & NOOUTERTHIS) == 0) {
2248 // Enclosing instance field is used
2249 return true;
2250 }
2251 if (rs.isSerializable(sym.type)) {
2252 // Class is serializable
2253 return true;
2254 }
2255 return false;
2256 }
2257
2258 List<JCTree> generateMandatedAccessors(JCClassDecl tree) {
2259 List<JCVariableDecl> fields = TreeInfo.recordFields(tree);
2260 return tree.sym.getRecordComponents().stream()
2261 .filter(rc -> (rc.accessor.flags() & Flags.GENERATED_MEMBER) != 0)
2262 .map(rc -> {
2263 // we need to return the field not the record component
2264 JCVariableDecl field = fields.stream().filter(f -> f.name == rc.name).findAny().get();
2265 make_at(tree.pos());
2266 return make.MethodDef(rc.accessor, make.Block(0,
2267 List.of(make.Return(make.Ident(field)))));
2268 }).collect(List.collector());
2269 }
2270
2271 /** Translate an enum class. */
2272 private void visitEnumDef(JCClassDecl tree) {
2273 make_at(tree.pos());
2274
2275 // add the supertype, if needed
2276 if (tree.extending == null)
2277 tree.extending = make.Type(types.supertype(tree.type));
2278
2279 // classOfType adds a cache field to tree.defs
2280 JCExpression e_class = classOfType(tree.sym.type, tree.pos()).
2281 setType(types.erasure(syms.classType));
2282
2283 // process each enumeration constant, adding implicit constructor parameters
2284 int nextOrdinal = 0;
2285 ListBuffer<JCExpression> values = new ListBuffer<>();
2286 ListBuffer<JCTree> enumDefs = new ListBuffer<>();
2287 ListBuffer<JCTree> otherDefs = new ListBuffer<>();
2288 for (List<JCTree> defs = tree.defs;
2289 defs.nonEmpty();
2290 defs=defs.tail) {
2291 if (defs.head.hasTag(VARDEF) && (((JCVariableDecl) defs.head).mods.flags & ENUM) != 0) {
2292 JCVariableDecl var = (JCVariableDecl)defs.head;
2293 visitEnumConstantDef(var, nextOrdinal++);
2294 values.append(make.QualIdent(var.sym));
2295 enumDefs.append(var);
2296 } else {
2297 otherDefs.append(defs.head);
2298 }
2299 }
2300
2301 // synthetic private static T[] $values() { return new T[] { a, b, c }; }
2302 // synthetic private static final T[] $VALUES = $values();
2303 Name valuesName = syntheticName(tree, "VALUES");
2304 Type arrayType = new ArrayType(types.erasure(tree.type), syms.arrayClass);
2305 VarSymbol valuesVar = new VarSymbol(PRIVATE|FINAL|STATIC|SYNTHETIC,
2306 valuesName,
2307 arrayType,
2308 tree.type.tsym);
2309 JCNewArray newArray = make.NewArray(make.Type(types.erasure(tree.type)),
2310 List.nil(),
2311 values.toList());
2312 newArray.type = arrayType;
2313
2314 MethodSymbol valuesMethod = new MethodSymbol(PRIVATE|STATIC|SYNTHETIC,
2315 syntheticName(tree, "values"),
2316 new MethodType(List.nil(), arrayType, List.nil(), tree.type.tsym),
2317 tree.type.tsym);
2318 enumDefs.append(make.MethodDef(valuesMethod, make.Block(0, List.of(make.Return(newArray)))));
2319 tree.sym.members().enter(valuesMethod);
2320
2321 enumDefs.append(make.VarDef(valuesVar, make.App(make.QualIdent(valuesMethod))));
2322 tree.sym.members().enter(valuesVar);
2323
2324 MethodSymbol valuesSym = lookupMethod(tree.pos(), names.values,
2325 tree.type, List.nil());
2326 List<JCStatement> valuesBody;
2327 if (useClone()) {
2328 // return (T[]) $VALUES.clone();
2329 JCTypeCast valuesResult =
2330 make.TypeCast(valuesSym.type.getReturnType(),
2331 make.App(make.Select(make.Ident(valuesVar),
2332 syms.arrayCloneMethod)));
2333 valuesBody = List.of(make.Return(valuesResult));
2334 } else {
2335 // template: T[] $result = new T[$values.length];
2336 Name resultName = syntheticName(tree, "result");
2337 VarSymbol resultVar = new VarSymbol(FINAL|SYNTHETIC,
2338 resultName,
2339 arrayType,
2340 valuesSym);
2341 JCNewArray resultArray = make.NewArray(make.Type(types.erasure(tree.type)),
2342 List.of(make.Select(make.Ident(valuesVar), syms.lengthVar)),
2343 null);
2344 resultArray.type = arrayType;
2345 JCVariableDecl decl = make.VarDef(resultVar, resultArray);
2346
2347 // template: System.arraycopy($VALUES, 0, $result, 0, $VALUES.length);
2348 if (systemArraycopyMethod == null) {
2349 systemArraycopyMethod =
2350 new MethodSymbol(PUBLIC | STATIC,
2351 names.fromString("arraycopy"),
2352 new MethodType(List.of(syms.objectType,
2353 syms.intType,
2354 syms.objectType,
2355 syms.intType,
2356 syms.intType),
2357 syms.voidType,
2358 List.nil(),
2359 syms.methodClass),
2360 syms.systemType.tsym);
2361 }
2362 JCStatement copy =
2363 make.Exec(make.App(make.Select(make.Ident(syms.systemType.tsym),
2364 systemArraycopyMethod),
2365 List.of(make.Ident(valuesVar), make.Literal(0),
2366 make.Ident(resultVar), make.Literal(0),
2367 make.Select(make.Ident(valuesVar), syms.lengthVar))));
2368
2369 // template: return $result;
2370 JCStatement ret = make.Return(make.Ident(resultVar));
2371 valuesBody = List.of(decl, copy, ret);
2372 }
2373
2374 JCMethodDecl valuesDef =
2375 make.MethodDef(valuesSym, make.Block(0, valuesBody));
2376
2377 enumDefs.append(valuesDef);
2378
2379 if (debugLower)
2380 System.err.println(tree.sym + ".valuesDef = " + valuesDef);
2381
2382 /** The template for the following code is:
2383 *
2384 * public static E valueOf(String name) {
2385 * return (E)Enum.valueOf(E.class, name);
2386 * }
2387 *
2388 * where E is tree.sym
2389 */
2390 MethodSymbol valueOfSym = lookupMethod(tree.pos(),
2391 names.valueOf,
2392 tree.sym.type,
2393 List.of(syms.stringType));
2394 Assert.check((valueOfSym.flags() & STATIC) != 0);
2395 VarSymbol nameArgSym = valueOfSym.params.head;
2396 JCIdent nameVal = make.Ident(nameArgSym);
2397 JCStatement enum_ValueOf =
2398 make.Return(make.TypeCast(tree.sym.type,
2399 makeCall(make.Ident(syms.enumSym),
2400 names.valueOf,
2401 List.of(e_class, nameVal))));
2402 JCMethodDecl valueOf = make.MethodDef(valueOfSym,
2403 make.Block(0, List.of(enum_ValueOf)));
2404 nameVal.sym = valueOf.params.head.sym;
2405 if (debugLower)
2406 System.err.println(tree.sym + ".valueOf = " + valueOf);
2407 enumDefs.append(valueOf);
2408
2409 enumDefs.appendList(otherDefs.toList());
2410 tree.defs = enumDefs.toList();
2411 }
2412 // where
2413 private MethodSymbol systemArraycopyMethod;
2414 private boolean useClone() {
2415 try {
2416 return syms.objectType.tsym.members().findFirst(names.clone) != null;
2417 }
2418 catch (CompletionFailure e) {
2419 return false;
2420 }
2421 }
2422
2423 private Name syntheticName(JCClassDecl tree, String baseName) {
2424 Name valuesName = names.fromString(target.syntheticNameChar() + baseName);
2425 while (tree.sym.members().findFirst(valuesName) != null) // avoid name clash
2426 valuesName = names.fromString(valuesName + "" + target.syntheticNameChar());
2427 return valuesName;
2428 }
2429
2430 /** Translate an enumeration constant and its initializer. */
2431 private void visitEnumConstantDef(JCVariableDecl var, int ordinal) {
2432 JCNewClass varDef = (JCNewClass)var.init;
2433 varDef.args = varDef.args.
2434 prepend(makeLit(syms.intType, ordinal)).
2435 prepend(makeLit(syms.stringType, var.name.toString()));
2436 }
2437
2438 private List<VarSymbol> recordVars(Type t) {
2439 List<VarSymbol> vars = List.nil();
2440 while (!t.hasTag(NONE)) {
2441 if (t.hasTag(CLASS)) {
2442 for (Symbol s : t.tsym.members().getSymbols(s -> s.kind == VAR && (s.flags() & RECORD) != 0)) {
2443 vars = vars.prepend((VarSymbol)s);
2444 }
2445 }
2446 t = types.supertype(t);
2447 }
2448 return vars;
2449 }
2450
2451 /** Translate a record. */
2452 private void visitRecordDef(JCClassDecl tree) {
2453 make_at(tree.pos());
2454 List<VarSymbol> vars = recordVars(tree.type);
2455 MethodHandleSymbol[] getterMethHandles = new MethodHandleSymbol[vars.size()];
2456 int index = 0;
2457 for (VarSymbol var : vars) {
2458 if (var.owner != tree.sym) {
2459 var = new VarSymbol(var.flags_field, var.name, var.type, tree.sym);
2460 }
2461 getterMethHandles[index] = var.asMethodHandle(true);
2462 index++;
2463 }
2464
2465 tree.defs = tree.defs.appendList(generateMandatedAccessors(tree));
2466 tree.defs = tree.defs.appendList(List.of(
2467 generateRecordMethod(tree, names.toString, vars, getterMethHandles),
2468 generateRecordMethod(tree, names.hashCode, vars, getterMethHandles),
2469 generateRecordMethod(tree, names.equals, vars, getterMethHandles)
2470 ));
2471 }
2472
2473 JCTree generateRecordMethod(JCClassDecl tree, Name name, List<VarSymbol> vars, MethodHandleSymbol[] getterMethHandles) {
2474 make_at(tree.pos());
2475 boolean isEquals = name == names.equals;
2476 MethodSymbol msym = lookupMethod(tree.pos(),
2477 name,
2478 tree.sym.type,
2479 isEquals ? List.of(syms.objectType) : List.nil());
2480 // compiler generated methods have the record flag set, user defined ones dont
2481 if ((msym.flags() & RECORD) != 0) {
2482 /* class java.lang.runtime.ObjectMethods provides a common bootstrap that provides a customized implementation
2483 * for methods: toString, hashCode and equals. Here we just need to generate and indy call to:
2484 * java.lang.runtime.ObjectMethods::bootstrap and provide: the record class, the record component names and
2485 * the accessors.
2486 */
2487 Name bootstrapName = names.bootstrap;
2488 LoadableConstant[] staticArgsValues = new LoadableConstant[2 + getterMethHandles.length];
2489 staticArgsValues[0] = (ClassType)tree.sym.type;
2490 String concatNames = vars.stream()
2491 .map(v -> v.name)
2492 .collect(Collectors.joining(";", "", ""));
2493 staticArgsValues[1] = LoadableConstant.String(concatNames);
2494 int index = 2;
2495 for (MethodHandleSymbol mho : getterMethHandles) {
2496 staticArgsValues[index] = mho;
2497 index++;
2498 }
2499
2500 List<Type> staticArgTypes = List.of(syms.classType,
2501 syms.stringType,
2502 new ArrayType(syms.methodHandleType, syms.arrayClass));
2503
2504 JCFieldAccess qualifier = makeIndyQualifier(syms.objectMethodsType, tree, msym,
2505 List.of(syms.methodHandleLookupType,
2506 syms.stringType,
2507 syms.typeDescriptorType).appendList(staticArgTypes),
2508 staticArgsValues, bootstrapName, name, false);
2509
2510 VarSymbol _this = new VarSymbol(SYNTHETIC, names._this, tree.sym.type, tree.sym);
2511
2512 JCMethodInvocation proxyCall;
2513 if (!isEquals) {
2514 proxyCall = make.Apply(List.nil(), qualifier, List.of(make.Ident(_this)));
2515 } else {
2516 VarSymbol o = msym.params.head;
2517 o.adr = 0;
2518 proxyCall = make.Apply(List.nil(), qualifier, List.of(make.Ident(_this), make.Ident(o)));
2519 }
2520 proxyCall.type = qualifier.type;
2521 return make.MethodDef(msym, make.Block(0, List.of(make.Return(proxyCall))));
2522 } else {
2523 return make.Block(SYNTHETIC, List.nil());
2524 }
2525 }
2526
2527 private String argsTypeSig(List<Type> typeList) {
2528 LowerSignatureGenerator sg = new LowerSignatureGenerator();
2529 sg.assembleSig(typeList);
2530 return sg.toString();
2531 }
2532
2533 /**
2534 * Signature Generation
2535 */
2536 private class LowerSignatureGenerator extends Types.SignatureGenerator {
2537
2538 /**
2539 * An output buffer for type signatures.
2540 */
2541 StringBuilder sb = new StringBuilder();
2542
2543 LowerSignatureGenerator() {
2544 types.super();
2545 }
2546
2547 @Override
2548 protected void append(char ch) {
2549 sb.append(ch);
2550 }
2551
2552 @Override
2553 protected void append(byte[] ba) {
2554 sb.append(new String(ba));
2555 }
2556
2557 @Override
2558 protected void append(Name name) {
2559 sb.append(name.toString());
2560 }
2561
2562 @Override
2563 public String toString() {
2564 return sb.toString();
2565 }
2566 }
2567
2568 /**
2569 * Creates an indy qualifier, helpful to be part of an indy invocation
2570 * @param site the site
2571 * @param tree a class declaration tree
2572 * @param msym the method symbol
2573 * @param staticArgTypes the static argument types
2574 * @param staticArgValues the static argument values
2575 * @param bootstrapName the bootstrap name to look for
2576 * @param argName normally bootstraps receives a method name as second argument, if you want that name
2577 * to be different to that of the bootstrap name pass a different name here
2578 * @param isStatic is it static or not
2579 * @return a field access tree
2580 */
2581 JCFieldAccess makeIndyQualifier(
2582 Type site,
2583 JCClassDecl tree,
2584 MethodSymbol msym,
2585 List<Type> staticArgTypes,
2586 LoadableConstant[] staticArgValues,
2587 Name bootstrapName,
2588 Name argName,
2589 boolean isStatic) {
2590 MethodSymbol bsm = rs.resolveInternalMethod(tree.pos(), attrEnv, site,
2591 bootstrapName, staticArgTypes, List.nil());
2592
2593 MethodType indyType = msym.type.asMethodType();
2594 indyType = new MethodType(
2595 isStatic ? List.nil() : indyType.argtypes.prepend(tree.sym.type),
2596 indyType.restype,
2597 indyType.thrown,
2598 syms.methodClass
2599 );
2600 DynamicMethodSymbol dynSym = new DynamicMethodSymbol(argName,
2601 syms.noSymbol,
2602 bsm.asHandle(),
2603 indyType,
2604 staticArgValues);
2605 JCFieldAccess qualifier = make.Select(make.QualIdent(site.tsym), argName);
2606 qualifier.sym = dynSym;
2607 qualifier.type = msym.type.asMethodType().restype;
2608 return qualifier;
2609 }
2610
2611 public void visitMethodDef(JCMethodDecl tree) {
2612 if (tree.name == names.init && (currentClass.flags_field&ENUM) != 0) {
2613 // Add "String $enum$name, int $enum$ordinal" to the beginning of the
2614 // argument list for each constructor of an enum.
2615 JCVariableDecl nameParam = make_at(tree.pos()).
2616 Param(names.fromString(target.syntheticNameChar() +
2617 "enum" + target.syntheticNameChar() + "name"),
2618 syms.stringType, tree.sym);
2619 nameParam.mods.flags |= SYNTHETIC; nameParam.sym.flags_field |= SYNTHETIC;
2620 JCVariableDecl ordParam = make.
2621 Param(names.fromString(target.syntheticNameChar() +
2622 "enum" + target.syntheticNameChar() +
2623 "ordinal"),
2624 syms.intType, tree.sym);
2625 ordParam.mods.flags |= SYNTHETIC; ordParam.sym.flags_field |= SYNTHETIC;
2626
2627 MethodSymbol m = tree.sym;
2628 tree.params = tree.params.prepend(ordParam).prepend(nameParam);
2629
2630 m.extraParams = m.extraParams.prepend(ordParam.sym);
2631 m.extraParams = m.extraParams.prepend(nameParam.sym);
2632 Type olderasure = m.erasure(types);
2633 m.erasure_field = new MethodType(
2634 olderasure.getParameterTypes().prepend(syms.intType).prepend(syms.stringType),
2635 olderasure.getReturnType(),
2636 olderasure.getThrownTypes(),
2637 syms.methodClass);
2638 }
2639
2640 Type prevRestype = currentRestype;
2641 JCMethodDecl prevMethodDef = currentMethodDef;
2642 MethodSymbol prevMethodSym = currentMethodSym;
2643 int prevVariableIndex = variableIndex;
2644 try {
2645 currentRestype = types.erasure(tree.type.getReturnType());
2646 currentMethodDef = tree;
2647 currentMethodSym = tree.sym;
2648 variableIndex = 0;
2649 visitMethodDefInternal(tree);
2650 } finally {
2651 currentRestype = prevRestype;
2652 currentMethodDef = prevMethodDef;
2653 currentMethodSym = prevMethodSym;
2654 variableIndex = prevVariableIndex;
2655 }
2656 }
2657
2658 private void visitMethodDefInternal(JCMethodDecl tree) {
2659 if (tree.name == names.init &&
2660 !currentClass.isStatic() &&
2661 (currentClass.isInner() || currentClass.isDirectlyOrIndirectlyLocal())) {
2662 // We are seeing a constructor of an inner class.
2663 MethodSymbol m = tree.sym;
2664
2665 // Push a new proxy scope for constructor parameters.
2666 // and create definitions for any this$n and proxy parameters.
2667 Map<Symbol, Symbol> prevProxies = proxies;
2668 proxies = new HashMap<>(proxies);
2669 List<VarSymbol> prevOuterThisStack = outerThisStack;
2670 List<VarSymbol> fvs = freevars(currentClass);
2671 JCVariableDecl otdef = null;
2672 if (currentClass.hasOuterInstance())
2673 otdef = outerThisDef(tree.pos, m);
2674 List<JCVariableDecl> fvdefs = freevarDefs(tree.pos, fvs, m, PARAMETER);
2675
2676 // Recursively translate result type, parameters and thrown list.
2677 tree.restype = translate(tree.restype);
2678 tree.params = translateVarDefs(tree.params);
2679 tree.thrown = translate(tree.thrown);
2680
2681 // when compiling stubs, don't process body
2682 if (tree.body == null) {
2683 result = tree;
2684 return;
2685 }
2686
2687 // Add this$n (if needed) in front of and free variables behind
2688 // constructor parameter list.
2689 tree.params = tree.params.appendList(fvdefs);
2690 if (currentClass.hasOuterInstance()) {
2691 tree.params = tree.params.prepend(otdef);
2692 }
2693
2694 // Determine whether this constructor has a super() invocation
2695 boolean invokesSuper = TreeInfo.hasConstructorCall(tree, names._super);
2696
2697 // Create initializers for this$n and proxies
2698 ListBuffer<JCStatement> added = new ListBuffer<>();
2699 if (fvs.nonEmpty()) {
2700 List<Type> addedargtypes = List.nil();
2701 for (List<VarSymbol> l = fvs; l.nonEmpty(); l = l.tail) {
2702 m.capturedLocals =
2703 m.capturedLocals.prepend((VarSymbol)
2704 (proxies.get(l.head)));
2705 if (invokesSuper) {
2706 added = added.prepend(
2707 initField(tree.body.pos, proxies.get(l.head), prevProxies.get(l.head)));
2708 }
2709 addedargtypes = addedargtypes.prepend(l.head.erasure(types));
2710 }
2711 Type olderasure = m.erasure(types);
2712 m.erasure_field = new MethodType(
2713 olderasure.getParameterTypes().appendList(addedargtypes),
2714 olderasure.getReturnType(),
2715 olderasure.getThrownTypes(),
2716 syms.methodClass);
2717 }
2718
2719 // Recursively translate existing local statements
2720 tree.body.stats = translate(tree.body.stats);
2721
2722 // Prepend initializers in front of super() call
2723 if (added.nonEmpty()) {
2724 List<JCStatement> initializers = added.toList();
2725 TreeInfo.mapSuperCalls(tree.body, supercall -> make.Block(0, initializers.append(supercall)));
2726 }
2727
2728 // pop local variables from proxy stack
2729 proxies = prevProxies;
2730
2731 outerThisStack = prevOuterThisStack;
2732 } else {
2733 super.visitMethodDef(tree);
2734 }
2735 if (tree.name == names.init && ((tree.sym.flags_field & Flags.COMPACT_RECORD_CONSTRUCTOR) != 0 ||
2736 (tree.sym.flags_field & (GENERATEDCONSTR | RECORD)) == (GENERATEDCONSTR | RECORD))) {
2737 // lets find out if there is any field waiting to be initialized
2738 ListBuffer<VarSymbol> fields = new ListBuffer<>();
2739 for (Symbol sym : currentClass.getEnclosedElements()) {
2740 if (sym.kind == Kinds.Kind.VAR && ((sym.flags() & RECORD) != 0))
2741 fields.append((VarSymbol) sym);
2742 }
2743 for (VarSymbol field: fields) {
2744 if ((field.flags_field & Flags.UNINITIALIZED_FIELD) != 0) {
2745 VarSymbol param = tree.params.stream().filter(p -> p.name == field.name).findFirst().get().sym;
2746 make.at(tree.pos);
2747 tree.body.stats = tree.body.stats.append(
2748 make.Exec(
2749 make.Assign(
2750 make.Select(make.This(field.owner.erasure(types)), field),
2751 make.Ident(param)).setType(field.erasure(types))));
2752 // we don't need the flag at the field anymore
2753 field.flags_field &= ~Flags.UNINITIALIZED_FIELD;
2754 }
2755 }
2756 }
2757 result = tree;
2758 }
2759
2760 public void visitTypeCast(JCTypeCast tree) {
2761 tree.clazz = translate(tree.clazz);
2762 if (tree.type.isPrimitive() != tree.expr.type.isPrimitive())
2763 tree.expr = translate(tree.expr, tree.type);
2764 else
2765 tree.expr = translate(tree.expr);
2766 result = tree;
2767 }
2768
2769 /**
2770 * All the exactness checks between primitive types that require a run-time
2771 * check are in {@code java.lang.runtime.ExactConversionsSupport}. Those methods
2772 * are in the form {@code ExactConversionsSupport.is<S>To<T>Exact} where both
2773 * {@code S} and {@code T} are primitive types and correspond to the runtime
2774 * action that will be executed to check whether a certain value (that is passed
2775 * as a parameter) can be converted to {@code T} without loss of information.
2776 *
2777 * Rewrite {@code instanceof if expr : Object} and Type is primitive type:
2778 *
2779 * {@snippet :
2780 * Object v = ...
2781 * if (v instanceof float)
2782 * =>
2783 * if (let tmp$123 = v; tmp$123 instanceof Float)
2784 * }
2785 *
2786 * Rewrite {@code instanceof if expr : wrapper reference type}
2787 *
2788 * {@snippet :
2789 * Integer v = ...
2790 * if (v instanceof float)
2791 * =>
2792 * if (let tmp$123 = v; tmp$123 != null && ExactConversionsSupport.intToFloatExact(tmp$123.intValue()))
2793 * }
2794 *
2795 * Rewrite {@code instanceof if expr : primitive}
2796 *
2797 * {@snippet :
2798 * int v = ...
2799 * if (v instanceof float)
2800 * =>
2801 * if (let tmp$123 = v; ExactConversionsSupport.intToFloatExact(tmp$123))
2802 * }
2803 *
2804 * More rewritings:
2805 * <ul>
2806 * <li>If the {@code instanceof} check is unconditionally exact rewrite to true.</li>
2807 * <li>If expression type is {@code Byte}, {@code Short}, {@code Integer}, ..., an
2808 * unboxing conversion followed by a widening primitive conversion.</li>
2809 * <li>If expression type is a supertype: {@code Number}, a narrowing reference
2810 * conversion followed by an unboxing conversion.</li>
2811 * </ul>
2812 */
2813 public void visitTypeTest(JCInstanceOf tree) {
2814 if (tree.expr.type.isPrimitive() || tree.pattern.type.isPrimitive()) {
2815 JCExpression exactnessCheck = null;
2816 JCExpression instanceOfExpr = translate(tree.expr);
2817
2818 // preserving the side effects of the value
2819 VarSymbol dollar_s = new VarSymbol(FINAL | SYNTHETIC,
2820 names.fromString("tmp" + variableIndex++ + this.target.syntheticNameChar()),
2821 types.erasure(tree.expr.type),
2822 currentMethodSym);
2823 JCStatement var = make.at(tree.pos())
2824 .VarDef(dollar_s, instanceOfExpr);
2825
2826 if (types.isUnconditionallyExact(tree.expr.type, tree.pattern.type)) {
2827 exactnessCheck = make.Literal(BOOLEAN, 1).setType(syms.booleanType.constType(1));
2828 }
2829 else if (tree.expr.type.isReference()) {
2830 JCExpression nullCheck =
2831 makeBinary(NE,
2832 make.Ident(dollar_s),
2833 makeNull());
2834
2835 if (types.isUnconditionallyExact(types.unboxedType(tree.expr.type), tree.pattern.type)) {
2836 exactnessCheck = nullCheck;
2837 } else if (types.unboxedType(tree.expr.type).isPrimitive()) {
2838 exactnessCheck =
2839 makeBinary(AND,
2840 nullCheck,
2841 getExactnessCheck(tree, boxIfNeeded(make.Ident(dollar_s), types.unboxedType(tree.expr.type))));
2842 } else {
2843 exactnessCheck =
2844 makeBinary(AND,
2845 nullCheck,
2846 make.at(tree.pos())
2847 .TypeTest(make.Ident(dollar_s), make.Type(types.boxedClass(tree.pattern.type).type))
2848 .setType(syms.booleanType));
2849 }
2850 }
2851 else if (tree.expr.type.isPrimitive()) {
2852 exactnessCheck = getExactnessCheck(tree, make.Ident(dollar_s));
2853 }
2854
2855 result = make.LetExpr(List.of(var), exactnessCheck)
2856 .setType(syms.booleanType);
2857 } else {
2858 tree.expr = translate(tree.expr);
2859 tree.pattern = translate(tree.pattern);
2860 result = tree;
2861 }
2862 }
2863
2864 // TypePairs should be in sync with the corresponding record in SwitchBootstraps
2865 record TypePairs(TypeSymbol from, TypeSymbol to) {
2866 public static TypePairs of(Symtab syms, Type from, Type to) {
2867 if (from == syms.byteType || from == syms.shortType || from == syms.charType) {
2868 from = syms.intType;
2869 }
2870 return new TypePairs(from, to);
2871 }
2872
2873 public TypePairs(Type from, Type to) {
2874 this(from.tsym, to.tsym);
2875 }
2876
2877 public static HashMap<TypePairs, String> initialize(Symtab syms) {
2878 HashMap<TypePairs, String> typePairToName = new HashMap<>();
2879 typePairToName.put(new TypePairs(syms.byteType, syms.charType), "isIntToCharExact"); // redirected
2880 typePairToName.put(new TypePairs(syms.shortType, syms.byteType), "isIntToByteExact"); // redirected
2881 typePairToName.put(new TypePairs(syms.shortType, syms.charType), "isIntToCharExact"); // redirected
2882 typePairToName.put(new TypePairs(syms.charType, syms.byteType), "isIntToByteExact"); // redirected
2883 typePairToName.put(new TypePairs(syms.charType, syms.shortType), "isIntToShortExact"); // redirected
2884 typePairToName.put(new TypePairs(syms.intType, syms.byteType), "isIntToByteExact");
2885 typePairToName.put(new TypePairs(syms.intType, syms.shortType), "isIntToShortExact");
2886 typePairToName.put(new TypePairs(syms.intType, syms.charType), "isIntToCharExact");
2887 typePairToName.put(new TypePairs(syms.intType, syms.floatType), "isIntToFloatExact");
2888 typePairToName.put(new TypePairs(syms.longType, syms.byteType), "isLongToByteExact");
2889 typePairToName.put(new TypePairs(syms.longType, syms.shortType), "isLongToShortExact");
2890 typePairToName.put(new TypePairs(syms.longType, syms.charType), "isLongToCharExact");
2891 typePairToName.put(new TypePairs(syms.longType, syms.intType), "isLongToIntExact");
2892 typePairToName.put(new TypePairs(syms.longType, syms.floatType), "isLongToFloatExact");
2893 typePairToName.put(new TypePairs(syms.longType, syms.doubleType), "isLongToDoubleExact");
2894 typePairToName.put(new TypePairs(syms.floatType, syms.byteType), "isFloatToByteExact");
2895 typePairToName.put(new TypePairs(syms.floatType, syms.shortType), "isFloatToShortExact");
2896 typePairToName.put(new TypePairs(syms.floatType, syms.charType), "isFloatToCharExact");
2897 typePairToName.put(new TypePairs(syms.floatType, syms.intType), "isFloatToIntExact");
2898 typePairToName.put(new TypePairs(syms.floatType, syms.longType), "isFloatToLongExact");
2899 typePairToName.put(new TypePairs(syms.doubleType, syms.byteType), "isDoubleToByteExact");
2900 typePairToName.put(new TypePairs(syms.doubleType, syms.shortType), "isDoubleToShortExact");
2901 typePairToName.put(new TypePairs(syms.doubleType, syms.charType), "isDoubleToCharExact");
2902 typePairToName.put(new TypePairs(syms.doubleType, syms.intType), "isDoubleToIntExact");
2903 typePairToName.put(new TypePairs(syms.doubleType, syms.longType), "isDoubleToLongExact");
2904 typePairToName.put(new TypePairs(syms.doubleType, syms.floatType), "isDoubleToFloatExact");
2905 return typePairToName;
2906 }
2907 }
2908
2909 private JCExpression getExactnessCheck(JCInstanceOf tree, JCExpression argument) {
2910 TypePairs pair = TypePairs.of(syms, types.unboxedTypeOrType(tree.expr.type), tree.pattern.type);
2911
2912 Name exactnessFunction = names.fromString(typePairToName.get(pair));
2913
2914 // Resolve the exactness method
2915 Symbol ecsym = lookupMethod(tree.pos(),
2916 exactnessFunction,
2917 syms.exactConversionsSupportType,
2918 List.of(pair.from.type));
2919
2920 // Generate the method call ExactnessChecks.<exactness method>(<argument>);
2921 JCFieldAccess select = make.Select(
2922 make.QualIdent(syms.exactConversionsSupportType.tsym),
2923 exactnessFunction);
2924 select.sym = ecsym;
2925 select.setType(syms.booleanType);
2926
2927 JCExpression exactnessCheck = make.Apply(List.nil(),
2928 select,
2929 List.of(argument));
2930 exactnessCheck.setType(syms.booleanType);
2931 return exactnessCheck;
2932 }
2933
2934 public void visitNewClass(JCNewClass tree) {
2935 ClassSymbol c = (ClassSymbol)tree.constructor.owner;
2936
2937 // Box arguments, if necessary
2938 boolean isEnum = (tree.constructor.owner.flags() & ENUM) != 0;
2939 List<Type> argTypes = tree.constructor.type.getParameterTypes();
2940 if (isEnum) argTypes = argTypes.prepend(syms.intType).prepend(syms.stringType);
2941 tree.args = boxArgs(argTypes, tree.args, tree.varargsElement);
2942 tree.varargsElement = null;
2943
2944 // If created class is local, add free variables after
2945 // explicit constructor arguments.
2946 if (c.isDirectlyOrIndirectlyLocal() && !c.isStatic()) {
2947 tree.args = tree.args.appendList(loadFreevars(tree.pos(), freevars(c)));
2948 }
2949
2950 // If an access constructor is used, append null as a last argument.
2951 Symbol constructor = accessConstructor(tree.pos(), tree.constructor);
2952 if (constructor != tree.constructor) {
2953 tree.args = tree.args.append(makeNull());
2954 tree.constructor = constructor;
2955 }
2956
2957 // If created class has an outer instance, and new is qualified, pass
2958 // qualifier as first argument. If new is not qualified, pass the
2959 // correct outer instance as first argument.
2960 if (c.hasOuterInstance()) {
2961 JCExpression thisArg;
2962 if (tree.encl != null) {
2963 thisArg = attr.makeNullCheck(translate(tree.encl));
2964 thisArg.type = tree.encl.type;
2965 } else if (c.isDirectlyOrIndirectlyLocal()) {
2966 // local class
2967 thisArg = makeThis(tree.pos(), c.innermostAccessibleEnclosingClass());
2968 } else {
2969 // nested class
2970 thisArg = makeOwnerThis(tree.pos(), c, false);
2971 }
2972 tree.args = tree.args.prepend(thisArg);
2973 }
2974 tree.encl = null;
2975
2976 // If we have an anonymous class, create its flat version, rather
2977 // than the class or interface following new.
2978 if (tree.def != null) {
2979 translate(tree.def);
2980
2981 tree.clazz = access(make_at(tree.clazz.pos()).Ident(tree.def.sym));
2982 tree.def = null;
2983 } else {
2984 tree.clazz = access(c, tree.clazz, enclOp, false);
2985 }
2986 result = tree;
2987 }
2988
2989 // Simplify conditionals with known constant controlling expressions.
2990 // This allows us to avoid generating supporting declarations for
2991 // the dead code, which will not be eliminated during code generation.
2992 // Note that Flow.isFalse and Flow.isTrue only return true
2993 // for constant expressions in the sense of JLS 15.27, which
2994 // are guaranteed to have no side-effects. More aggressive
2995 // constant propagation would require that we take care to
2996 // preserve possible side-effects in the condition expression.
2997
2998 // One common case is equality expressions involving a constant and null.
2999 // Since null is not a constant expression (because null cannot be
3000 // represented in the constant pool), equality checks involving null are
3001 // not captured by Flow.isTrue/isFalse.
3002 // Equality checks involving a constant and null, e.g.
3003 // "" == null
3004 // are safe to simplify as no side-effects can occur.
3005
3006 private boolean isTrue(JCTree exp) {
3007 if (exp.type.isTrue())
3008 return true;
3009 Boolean b = expValue(exp);
3010 return b == null ? false : b;
3011 }
3012 private boolean isFalse(JCTree exp) {
3013 if (exp.type.isFalse())
3014 return true;
3015 Boolean b = expValue(exp);
3016 return b == null ? false : !b;
3017 }
3018 /* look for (in)equality relations involving null.
3019 * return true - if expression is always true
3020 * false - if expression is always false
3021 * null - if expression cannot be eliminated
3022 */
3023 private Boolean expValue(JCTree exp) {
3024 while (exp.hasTag(PARENS))
3025 exp = ((JCParens)exp).expr;
3026
3027 boolean eq;
3028 switch (exp.getTag()) {
3029 case EQ: eq = true; break;
3030 case NE: eq = false; break;
3031 default:
3032 return null;
3033 }
3034
3035 // we have a JCBinary(EQ|NE)
3036 // check if we have two literals (constants or null)
3037 JCBinary b = (JCBinary)exp;
3038 if (b.lhs.type.hasTag(BOT)) return expValueIsNull(eq, b.rhs);
3039 if (b.rhs.type.hasTag(BOT)) return expValueIsNull(eq, b.lhs);
3040 return null;
3041 }
3042 private Boolean expValueIsNull(boolean eq, JCTree t) {
3043 if (t.type.hasTag(BOT)) return Boolean.valueOf(eq);
3044 if (t.hasTag(LITERAL)) return Boolean.valueOf(!eq);
3045 return null;
3046 }
3047
3048 /** Visitor method for conditional expressions.
3049 */
3050 @Override
3051 public void visitConditional(JCConditional tree) {
3052 JCTree cond = tree.cond = translate(tree.cond, syms.booleanType);
3053 if (isTrue(cond) && noClassDefIn(tree.falsepart)) {
3054 result = convert(translate(tree.truepart, tree.type), tree.type);
3055 addPrunedInfo(cond);
3056 } else if (isFalse(cond) && noClassDefIn(tree.truepart)) {
3057 result = convert(translate(tree.falsepart, tree.type), tree.type);
3058 addPrunedInfo(cond);
3059 } else {
3060 // Condition is not a compile-time constant.
3061 tree.truepart = translate(tree.truepart, tree.type);
3062 tree.falsepart = translate(tree.falsepart, tree.type);
3063 result = tree;
3064 }
3065 }
3066 //where
3067 private JCExpression convert(JCExpression tree, Type pt) {
3068 if (tree.type == pt || tree.type.hasTag(BOT))
3069 return tree;
3070 JCExpression result = make_at(tree.pos()).TypeCast(make.Type(pt), tree);
3071 result.type = (tree.type.constValue() != null) ? cfolder.coerce(tree.type, pt)
3072 : pt;
3073 return result;
3074 }
3075
3076 /** Visitor method for if statements.
3077 */
3078 public void visitIf(JCIf tree) {
3079 JCTree cond = tree.cond = translate(tree.cond, syms.booleanType);
3080 if (isTrue(cond) && noClassDefIn(tree.elsepart)) {
3081 result = translate(tree.thenpart);
3082 addPrunedInfo(cond);
3083 } else if (isFalse(cond) && noClassDefIn(tree.thenpart)) {
3084 if (tree.elsepart != null) {
3085 result = translate(tree.elsepart);
3086 } else {
3087 result = make.Skip();
3088 }
3089 addPrunedInfo(cond);
3090 } else {
3091 // Condition is not a compile-time constant.
3092 tree.thenpart = translate(tree.thenpart);
3093 tree.elsepart = translate(tree.elsepart);
3094 result = tree;
3095 }
3096 }
3097
3098 /** Visitor method for assert statements. Translate them away.
3099 */
3100 public void visitAssert(JCAssert tree) {
3101 tree.cond = translate(tree.cond, syms.booleanType);
3102 if (!tree.cond.type.isTrue()) {
3103 JCExpression cond = assertFlagTest(tree.pos());
3104 List<JCExpression> exnArgs = (tree.detail == null) ?
3105 List.nil() : List.of(translate(tree.detail));
3106 if (!tree.cond.type.isFalse()) {
3107 cond = makeBinary
3108 (AND,
3109 cond,
3110 makeUnary(NOT, tree.cond));
3111 }
3112 result =
3113 make.If(cond,
3114 make_at(tree).
3115 Throw(makeNewClass(syms.assertionErrorType, exnArgs)),
3116 null);
3117 } else {
3118 result = make.Skip();
3119 }
3120 }
3121
3122 public void visitApply(JCMethodInvocation tree) {
3123 Symbol meth = TreeInfo.symbol(tree.meth);
3124 List<Type> argtypes = meth.type.getParameterTypes();
3125 if (meth.name == names.init && meth.owner == syms.enumSym)
3126 argtypes = argtypes.tail.tail;
3127 tree.args = boxArgs(argtypes, tree.args, tree.varargsElement);
3128 tree.varargsElement = null;
3129 Name methName = TreeInfo.name(tree.meth);
3130 if (meth.name==names.init) {
3131 // We are seeing a this(...) or super(...) constructor call.
3132 // If an access constructor is used, append null as a last argument.
3133 Symbol constructor = accessConstructor(tree.pos(), meth);
3134 if (constructor != meth) {
3135 tree.args = tree.args.append(makeNull());
3136 TreeInfo.setSymbol(tree.meth, constructor);
3137 }
3138
3139 // If we are calling a constructor of a local class, add
3140 // free variables after explicit constructor arguments.
3141 ClassSymbol c = (ClassSymbol)constructor.owner;
3142 if (c.isDirectlyOrIndirectlyLocal() && !c.isStatic()) {
3143 tree.args = tree.args.appendList(loadFreevars(tree.pos(), freevars(c)));
3144 }
3145
3146 // If we are calling a constructor of an enum class, pass
3147 // along the name and ordinal arguments
3148 if ((c.flags_field&ENUM) != 0 || c.getQualifiedName() == names.java_lang_Enum) {
3149 List<JCVariableDecl> params = currentMethodDef.params;
3150 if (currentMethodSym.owner.hasOuterInstance())
3151 params = params.tail; // drop this$n
3152 tree.args = tree.args
3153 .prepend(make_at(tree.pos()).Ident(params.tail.head.sym)) // ordinal
3154 .prepend(make.Ident(params.head.sym)); // name
3155 }
3156
3157 // If we are calling a constructor of a class with an outer
3158 // instance, and the call
3159 // is qualified, pass qualifier as first argument in front of
3160 // the explicit constructor arguments. If the call
3161 // is not qualified, pass the correct outer instance as
3162 // first argument. If we are a static class, there is no
3163 // such outer instance, so generate an error.
3164 if (c.hasOuterInstance()) {
3165 JCExpression thisArg;
3166 if (tree.meth.hasTag(SELECT)) {
3167 thisArg = attr.
3168 makeNullCheck(translate(((JCFieldAccess) tree.meth).selected));
3169 tree.meth = make.Ident(constructor);
3170 ((JCIdent) tree.meth).name = methName;
3171 } else if (c.isDirectlyOrIndirectlyLocal() || methName == names._this){
3172 // local class or this() call
3173 thisArg = makeThis(tree.meth.pos(), c.innermostAccessibleEnclosingClass());
3174 } else if (currentClass.isStatic()) {
3175 // super() call from static nested class - invalid
3176 log.error(tree.pos(),
3177 Errors.NoEnclInstanceOfTypeInScope(c.type.getEnclosingType().tsym));
3178 thisArg = make.Literal(BOT, null).setType(syms.botType);
3179 } else {
3180 // super() call of nested class - never pick 'this'
3181 thisArg = makeOwnerThisN(tree.meth.pos(), c, false);
3182 }
3183 tree.args = tree.args.prepend(thisArg);
3184 }
3185 } else {
3186 // We are seeing a normal method invocation; translate this as usual.
3187 tree.meth = translate(tree.meth);
3188
3189 // If the translated method itself is an Apply tree, we are
3190 // seeing an access method invocation. In this case, append
3191 // the method arguments to the arguments of the access method.
3192 if (tree.meth.hasTag(APPLY)) {
3193 JCMethodInvocation app = (JCMethodInvocation)tree.meth;
3194 app.args = tree.args.prependList(app.args);
3195 result = app;
3196 return;
3197 }
3198 }
3199 if (tree.args.stream().anyMatch(c -> c == null)) {
3200 throw new AssertionError("Whooops before: " + tree);
3201 }
3202 result = tree;
3203 }
3204
3205 List<JCExpression> boxArgs(List<Type> parameters, List<JCExpression> _args, Type varargsElement) {
3206 List<JCExpression> args = _args;
3207 if (parameters.isEmpty()) return args;
3208 boolean anyChanges = false;
3209 ListBuffer<JCExpression> result = new ListBuffer<>();
3210 while (parameters.tail.nonEmpty()) {
3211 JCExpression arg = translate(args.head, parameters.head);
3212 anyChanges |= (arg != args.head);
3213 result.append(arg);
3214 args = args.tail;
3215 parameters = parameters.tail;
3216 }
3217 Type parameter = parameters.head;
3218 if (varargsElement != null) {
3219 anyChanges = true;
3220 ListBuffer<JCExpression> elems = new ListBuffer<>();
3221 while (args.nonEmpty()) {
3222 JCExpression arg = translate(args.head, varargsElement);
3223 elems.append(arg);
3224 args = args.tail;
3225 }
3226 JCNewArray boxedArgs = make.NewArray(make.Type(varargsElement),
3227 List.nil(),
3228 elems.toList());
3229 boxedArgs.type = new ArrayType(varargsElement, syms.arrayClass);
3230 result.append(boxedArgs);
3231 } else {
3232 if (args.length() != 1) throw new AssertionError(args);
3233 JCExpression arg = translate(args.head, parameter);
3234 anyChanges |= (arg != args.head);
3235 result.append(arg);
3236 if (!anyChanges) return _args;
3237 }
3238 return result.toList();
3239 }
3240
3241 /** Expand a boxing or unboxing conversion if needed. */
3242 @SuppressWarnings("unchecked") // XXX unchecked
3243 <T extends JCExpression> T boxIfNeeded(T tree, Type type) {
3244 Assert.check(!type.hasTag(VOID));
3245 if (type.hasTag(NONE))
3246 return tree;
3247 boolean havePrimitive = tree.type.isPrimitive();
3248 if (havePrimitive == type.isPrimitive())
3249 return tree;
3250 if (havePrimitive) {
3251 Type unboxedTarget = types.unboxedType(type);
3252 if (!unboxedTarget.hasTag(NONE)) {
3253 if (!types.isSubtype(tree.type, unboxedTarget)) //e.g. Character c = 89;
3254 tree.type = unboxedTarget.constType(tree.type.constValue());
3255 return (T)boxPrimitive(tree, types.erasure(type));
3256 } else {
3257 tree = (T)boxPrimitive(tree);
3258 }
3259 } else {
3260 tree = (T)unbox(tree, type);
3261 }
3262 return tree;
3263 }
3264
3265 /** Box up a single primitive expression. */
3266 JCExpression boxPrimitive(JCExpression tree) {
3267 return boxPrimitive(tree, types.boxedClass(tree.type).type);
3268 }
3269
3270 /** Box up a single primitive expression. */
3271 JCExpression boxPrimitive(JCExpression tree, Type box) {
3272 make_at(tree.pos());
3273 Symbol valueOfSym = lookupMethod(tree.pos(),
3274 names.valueOf,
3275 box,
3276 List.<Type>nil()
3277 .prepend(tree.type));
3278 return make.App(make.QualIdent(valueOfSym), List.of(tree));
3279 }
3280
3281 /** Unbox an object to a primitive value. */
3282 JCExpression unbox(JCExpression tree, Type primitive) {
3283 Type unboxedType = types.unboxedType(tree.type);
3284 if (unboxedType.hasTag(NONE)) {
3285 unboxedType = primitive;
3286 if (!unboxedType.isPrimitive())
3287 throw new AssertionError(unboxedType);
3288 make_at(tree.pos());
3289 tree = make.TypeCast(types.boxedClass(unboxedType).type, tree);
3290 } else {
3291 // There must be a conversion from unboxedType to primitive.
3292 if (!types.isSubtype(unboxedType, primitive))
3293 throw new AssertionError(tree);
3294 }
3295 make_at(tree.pos());
3296 Symbol valueSym = lookupMethod(tree.pos(),
3297 unboxedType.tsym.name.append(names.Value), // x.intValue()
3298 tree.type,
3299 List.nil());
3300 return make.App(make.Select(tree, valueSym));
3301 }
3302
3303 /** Visitor method for parenthesized expressions.
3304 * If the subexpression has changed, omit the parens.
3305 */
3306 public void visitParens(JCParens tree) {
3307 JCTree expr = translate(tree.expr);
3308 result = ((expr == tree.expr) ? tree : expr);
3309 }
3310
3311 public void visitIndexed(JCArrayAccess tree) {
3312 tree.indexed = translate(tree.indexed);
3313 tree.index = translate(tree.index, syms.intType);
3314 result = tree;
3315 }
3316
3317 public void visitAssign(JCAssign tree) {
3318 tree.lhs = translate(tree.lhs, tree);
3319 tree.rhs = translate(tree.rhs, tree.lhs.type);
3320
3321 // If translated left hand side is an Apply, we are
3322 // seeing an access method invocation. In this case, append
3323 // right hand side as last argument of the access method.
3324 if (tree.lhs.hasTag(APPLY)) {
3325 JCMethodInvocation app = (JCMethodInvocation)tree.lhs;
3326 app.args = List.of(tree.rhs).prependList(app.args);
3327 result = app;
3328 } else {
3329 result = tree;
3330 }
3331 }
3332
3333 public void visitAssignop(final JCAssignOp tree) {
3334 final boolean boxingReq = !tree.lhs.type.isPrimitive() &&
3335 tree.operator.type.getReturnType().isPrimitive();
3336
3337 AssignopDependencyScanner depScanner = new AssignopDependencyScanner(tree);
3338 depScanner.scan(tree.rhs);
3339
3340 if (boxingReq || depScanner.dependencyFound) {
3341 // boxing required; need to rewrite as x = (unbox typeof x)(x op y);
3342 // or if x == (typeof x)z then z = (unbox typeof x)((typeof x)z op y)
3343 // (but without recomputing x)
3344 JCTree newTree = abstractLval(tree.lhs, lhs -> {
3345 Tag newTag = tree.getTag().noAssignOp();
3346 // Erasure (TransTypes) can change the type of
3347 // tree.lhs. However, we can still get the
3348 // unerased type of tree.lhs as it is stored
3349 // in tree.type in Attr.
3350 OperatorSymbol newOperator = operators.resolveBinary(tree,
3351 newTag,
3352 tree.type,
3353 tree.rhs.type);
3354 //Need to use the "lhs" at two places, once on the future left hand side
3355 //and once in the future binary operator. But further processing may change
3356 //the components of the tree in place (see visitSelect for e.g. <Class>.super.<ident>),
3357 //so cloning the tree to avoid interference between the uses:
3358 JCExpression expr = (JCExpression) lhs.clone();
3359 if (expr.type != tree.type)
3360 expr = make.TypeCast(tree.type, expr);
3361 JCBinary opResult = make.Binary(newTag, expr, tree.rhs);
3362 opResult.operator = newOperator;
3363 opResult.type = newOperator.type.getReturnType();
3364 JCExpression newRhs = boxingReq ?
3365 make.TypeCast(types.unboxedType(tree.type), opResult) :
3366 opResult;
3367 return make.Assign(lhs, newRhs).setType(tree.type);
3368 });
3369 result = translate(newTree);
3370 return;
3371 }
3372 tree.lhs = translate(tree.lhs, tree);
3373 tree.rhs = translate(tree.rhs, tree.operator.type.getParameterTypes().tail.head);
3374
3375 // If translated left hand side is an Apply, we are
3376 // seeing an access method invocation. In this case, append
3377 // right hand side as last argument of the access method.
3378 if (tree.lhs.hasTag(APPLY)) {
3379 JCMethodInvocation app = (JCMethodInvocation)tree.lhs;
3380 // if operation is a += on strings,
3381 // make sure to convert argument to string
3382 JCExpression rhs = tree.operator.opcode == string_add
3383 ? makeString(tree.rhs)
3384 : tree.rhs;
3385 app.args = List.of(rhs).prependList(app.args);
3386 result = app;
3387 } else {
3388 result = tree;
3389 }
3390 }
3391
3392 class AssignopDependencyScanner extends TreeScanner {
3393
3394 Symbol sym;
3395 boolean dependencyFound = false;
3396
3397 AssignopDependencyScanner(JCAssignOp tree) {
3398 this.sym = TreeInfo.symbol(tree.lhs);
3399 }
3400
3401 @Override
3402 public void scan(JCTree tree) {
3403 if (tree != null && sym != null) {
3404 tree.accept(this);
3405 }
3406 }
3407
3408 @Override
3409 public void visitAssignop(JCAssignOp tree) {
3410 if (TreeInfo.symbol(tree.lhs) == sym) {
3411 dependencyFound = true;
3412 return;
3413 }
3414 super.visitAssignop(tree);
3415 }
3416
3417 @Override
3418 public void visitUnary(JCUnary tree) {
3419 if (TreeInfo.symbol(tree.arg) == sym) {
3420 dependencyFound = true;
3421 return;
3422 }
3423 super.visitUnary(tree);
3424 }
3425 }
3426
3427 /** Lower a tree of the form e++ or e-- where e is an object type */
3428 JCExpression lowerBoxedPostop(final JCUnary tree) {
3429 // translate to tmp1=lval(e); tmp2=tmp1; tmp1 OP 1; tmp2
3430 // or
3431 // translate to tmp1=lval(e); tmp2=tmp1; (typeof tree)tmp1 OP 1; tmp2
3432 // where OP is += or -=
3433 final boolean cast = TreeInfo.skipParens(tree.arg).hasTag(TYPECAST);
3434 return abstractLval(tree.arg, tmp1 -> abstractRval(tmp1, tree.arg.type, tmp2 -> {
3435 Tag opcode = (tree.hasTag(POSTINC))
3436 ? PLUS_ASG : MINUS_ASG;
3437 //"tmp1" and "tmp2" may refer to the same instance
3438 //(for e.g. <Class>.super.<ident>). But further processing may
3439 //change the components of the tree in place (see visitSelect),
3440 //so cloning the tree to avoid interference between the two uses:
3441 JCExpression lhs = (JCExpression)tmp1.clone();
3442 lhs = cast
3443 ? make.TypeCast(tree.arg.type, lhs)
3444 : lhs;
3445 JCExpression update = makeAssignop(opcode,
3446 lhs,
3447 make.Literal(1));
3448 return makeComma(update, tmp2);
3449 }));
3450 }
3451
3452 public void visitUnary(JCUnary tree) {
3453 boolean isUpdateOperator = tree.getTag().isIncOrDecUnaryOp();
3454 if (isUpdateOperator && !tree.arg.type.isPrimitive()) {
3455 switch(tree.getTag()) {
3456 case PREINC: // ++ e
3457 // translate to e += 1
3458 case PREDEC: // -- e
3459 // translate to e -= 1
3460 {
3461 JCTree.Tag opcode = (tree.hasTag(PREINC))
3462 ? PLUS_ASG : MINUS_ASG;
3463 JCAssignOp newTree = makeAssignop(opcode,
3464 tree.arg,
3465 make.Literal(1));
3466 result = translate(newTree, tree.type);
3467 return;
3468 }
3469 case POSTINC: // e ++
3470 case POSTDEC: // e --
3471 {
3472 result = translate(lowerBoxedPostop(tree), tree.type);
3473 return;
3474 }
3475 }
3476 throw new AssertionError(tree);
3477 }
3478
3479 tree.arg = boxIfNeeded(translate(tree.arg, tree), tree.type);
3480
3481 if (tree.hasTag(NOT) && tree.arg.type.constValue() != null) {
3482 tree.type = cfolder.fold1(bool_not, tree.arg.type);
3483 }
3484
3485 // If translated left hand side is an Apply, we are
3486 // seeing an access method invocation. In this case, return
3487 // that access method invocation as result.
3488 if (isUpdateOperator && tree.arg.hasTag(APPLY)) {
3489 result = tree.arg;
3490 } else {
3491 result = tree;
3492 }
3493 }
3494
3495 public void visitBinary(JCBinary tree) {
3496 List<Type> formals = tree.operator.type.getParameterTypes();
3497 JCTree lhs = tree.lhs = translate(tree.lhs, formals.head);
3498 switch (tree.getTag()) {
3499 case OR:
3500 if (isTrue(lhs)) {
3501 result = lhs;
3502 return;
3503 }
3504 if (isFalse(lhs)) {
3505 result = translate(tree.rhs, formals.tail.head);
3506 return;
3507 }
3508 break;
3509 case AND:
3510 if (isFalse(lhs)) {
3511 result = lhs;
3512 return;
3513 }
3514 if (isTrue(lhs)) {
3515 result = translate(tree.rhs, formals.tail.head);
3516 return;
3517 }
3518 break;
3519 }
3520 tree.rhs = translate(tree.rhs, formals.tail.head);
3521 result = tree;
3522 }
3523
3524 public void visitIdent(JCIdent tree) {
3525 result = access(tree.sym, tree, enclOp, false);
3526 }
3527
3528 /** Translate away the foreach loop. */
3529 public void visitForeachLoop(JCEnhancedForLoop tree) {
3530 if (types.elemtype(tree.expr.type) == null)
3531 visitIterableForeachLoop(tree);
3532 else
3533 visitArrayForeachLoop(tree);
3534 }
3535 // where
3536 /**
3537 * A statement of the form
3538 *
3539 * <pre>
3540 * for ( T v : arrayexpr ) stmt;
3541 * </pre>
3542 *
3543 * (where arrayexpr is of an array type) gets translated to
3544 *
3545 * <pre>{@code
3546 * for ( { arraytype #arr = arrayexpr;
3547 * int #len = array.length;
3548 * int #i = 0; };
3549 * #i < #len; i$++ ) {
3550 * T v = arr$[#i];
3551 * stmt;
3552 * }
3553 * }</pre>
3554 *
3555 * where #arr, #len, and #i are freshly named synthetic local variables.
3556 */
3557 private void visitArrayForeachLoop(JCEnhancedForLoop tree) {
3558 make_at(tree.expr.pos());
3559 VarSymbol arraycache = new VarSymbol(SYNTHETIC,
3560 names.fromString("arr" + target.syntheticNameChar()),
3561 tree.expr.type,
3562 currentMethodSym);
3563 JCStatement arraycachedef = make.VarDef(arraycache, tree.expr);
3564 VarSymbol lencache = new VarSymbol(SYNTHETIC,
3565 names.fromString("len" + target.syntheticNameChar()),
3566 syms.intType,
3567 currentMethodSym);
3568 JCStatement lencachedef = make.
3569 VarDef(lencache, make.Select(make.Ident(arraycache), syms.lengthVar));
3570 VarSymbol index = new VarSymbol(SYNTHETIC,
3571 names.fromString("i" + target.syntheticNameChar()),
3572 syms.intType,
3573 currentMethodSym);
3574
3575 JCVariableDecl indexdef = make.VarDef(index, make.Literal(INT, 0));
3576 indexdef.init.type = indexdef.type = syms.intType.constType(0);
3577
3578 List<JCStatement> loopinit = List.of(arraycachedef, lencachedef, indexdef);
3579 JCBinary cond = makeBinary(LT, make.Ident(index), make.Ident(lencache));
3580
3581 JCExpressionStatement step = make.Exec(makeUnary(PREINC, make.Ident(index)));
3582
3583 Type elemtype = types.elemtype(tree.expr.type);
3584 JCExpression loopvarinit = make.Indexed(make.Ident(arraycache),
3585 make.Ident(index)).setType(elemtype);
3586 JCVariableDecl loopvardef = (JCVariableDecl)make.VarDef(tree.var.mods,
3587 tree.var.name,
3588 tree.var.vartype,
3589 loopvarinit).setType(tree.var.type);
3590 loopvardef.sym = tree.var.sym;
3591 JCBlock body = make.
3592 Block(0, List.of(loopvardef, tree.body));
3593
3594 result = translate(make.
3595 ForLoop(loopinit,
3596 cond,
3597 List.of(step),
3598 body));
3599 patchTargets(body, tree, result);
3600 }
3601 /** Patch up break and continue targets. */
3602 private void patchTargets(JCTree body, final JCTree src, final JCTree dest) {
3603 class Patcher extends TreeScanner {
3604 public void visitBreak(JCBreak tree) {
3605 if (tree.target == src)
3606 tree.target = dest;
3607 }
3608 public void visitYield(JCYield tree) {
3609 if (tree.target == src)
3610 tree.target = dest;
3611 scan(tree.value);
3612 }
3613 public void visitContinue(JCContinue tree) {
3614 if (tree.target == src)
3615 tree.target = dest;
3616 }
3617 public void visitClassDef(JCClassDecl tree) {}
3618 }
3619 new Patcher().scan(body);
3620 }
3621 /**
3622 * A statement of the form
3623 *
3624 * <pre>
3625 * for ( T v : coll ) stmt ;
3626 * </pre>
3627 *
3628 * (where coll implements {@code Iterable<? extends T>}) gets translated to
3629 *
3630 * <pre>{@code
3631 * for ( Iterator<? extends T> #i = coll.iterator(); #i.hasNext(); ) {
3632 * T v = (T) #i.next();
3633 * stmt;
3634 * }
3635 * }</pre>
3636 *
3637 * where #i is a freshly named synthetic local variable.
3638 */
3639 private void visitIterableForeachLoop(JCEnhancedForLoop tree) {
3640 make_at(tree.expr.pos());
3641 Type iteratorTarget = syms.objectType;
3642 Type iterableType = types.asSuper(types.cvarUpperBound(tree.expr.type),
3643 syms.iterableType.tsym);
3644 if (iterableType.getTypeArguments().nonEmpty())
3645 iteratorTarget = types.erasure(iterableType.getTypeArguments().head);
3646 tree.expr.type = types.erasure(types.skipTypeVars(tree.expr.type, false));
3647 tree.expr = transTypes.coerce(attrEnv, tree.expr, types.erasure(iterableType));
3648 Symbol iterator = lookupMethod(tree.expr.pos(),
3649 names.iterator,
3650 tree.expr.type,
3651 List.nil());
3652 Assert.check(types.isSameType(types.erasure(types.asSuper(iterator.type.getReturnType(), syms.iteratorType.tsym)), types.erasure(syms.iteratorType)));
3653 VarSymbol itvar = new VarSymbol(SYNTHETIC, names.fromString("i" + target.syntheticNameChar()),
3654 types.erasure(syms.iteratorType),
3655 currentMethodSym);
3656
3657 JCStatement init = make.
3658 VarDef(itvar, make.App(make.Select(tree.expr, iterator)
3659 .setType(types.erasure(iterator.type))));
3660
3661 Symbol hasNext = lookupMethod(tree.expr.pos(),
3662 names.hasNext,
3663 itvar.type,
3664 List.nil());
3665 JCMethodInvocation cond = make.App(make.Select(make.Ident(itvar), hasNext));
3666 Symbol next = lookupMethod(tree.expr.pos(),
3667 names.next,
3668 itvar.type,
3669 List.nil());
3670 JCExpression vardefinit = make.App(make.Select(make.Ident(itvar), next));
3671 if (tree.var.type.isPrimitive())
3672 vardefinit = make.TypeCast(types.cvarUpperBound(iteratorTarget), vardefinit);
3673 else
3674 vardefinit = make.TypeCast(tree.var.type, vardefinit);
3675 JCVariableDecl indexDef = (JCVariableDecl)make.VarDef(tree.var.mods,
3676 tree.var.name,
3677 tree.var.vartype,
3678 vardefinit).setType(tree.var.type);
3679 indexDef.sym = tree.var.sym;
3680 JCBlock body = make.Block(0, List.of(indexDef, tree.body));
3681 body.endpos = TreeInfo.endPos(tree.body);
3682 result = translate(make.
3683 ForLoop(List.of(init),
3684 cond,
3685 List.nil(),
3686 body));
3687 patchTargets(body, tree, result);
3688 }
3689
3690 public void visitVarDef(JCVariableDecl tree) {
3691 MethodSymbol oldMethodSym = currentMethodSym;
3692 int prevVariableIndex = variableIndex;
3693 tree.mods = translate(tree.mods);
3694 tree.vartype = translate(tree.vartype);
3695 if (currentMethodSym == null) {
3696 // A class or instance field initializer.
3697 currentMethodSym =
3698 new MethodSymbol((tree.mods.flags&STATIC) | BLOCK,
3699 names.empty, null,
3700 currentClass);
3701 }
3702 try {
3703 if (tree.init != null) tree.init = translate(tree.init, tree.type);
3704 result = tree;
3705 } finally {
3706 currentMethodSym = oldMethodSym;
3707 variableIndex = prevVariableIndex;
3708 }
3709 }
3710
3711 public void visitBlock(JCBlock tree) {
3712 MethodSymbol oldMethodSym = currentMethodSym;
3713 if (currentMethodSym == null) {
3714 // Block is a static or instance initializer.
3715 currentMethodSym =
3716 new MethodSymbol(tree.flags | BLOCK,
3717 names.empty, null,
3718 currentClass);
3719 }
3720 int prevVariableIndex = variableIndex;
3721 try {
3722 variableIndex = 0;
3723 super.visitBlock(tree);
3724 } finally {
3725 currentMethodSym = oldMethodSym;
3726 variableIndex = prevVariableIndex;
3727 }
3728 }
3729
3730 public void visitDoLoop(JCDoWhileLoop tree) {
3731 tree.body = translate(tree.body);
3732 tree.cond = translate(tree.cond, syms.booleanType);
3733 result = tree;
3734 }
3735
3736 public void visitWhileLoop(JCWhileLoop tree) {
3737 tree.cond = translate(tree.cond, syms.booleanType);
3738 tree.body = translate(tree.body);
3739 result = tree;
3740 }
3741
3742 public void visitForLoop(JCForLoop tree) {
3743 tree.init = translate(tree.init);
3744 if (tree.cond != null)
3745 tree.cond = translate(tree.cond, syms.booleanType);
3746 tree.step = translate(tree.step);
3747 tree.body = translate(tree.body);
3748 result = tree;
3749 }
3750
3751 public void visitReturn(JCReturn tree) {
3752 if (tree.expr != null)
3753 tree.expr = translate(tree.expr,
3754 currentRestype);
3755 result = tree;
3756 }
3757
3758 @Override
3759 public void visitLambda(JCLambda tree) {
3760 Type prevRestype = currentRestype;
3761 try {
3762 currentRestype = types.erasure(tree.getDescriptorType(types)).getReturnType();
3763 // represent void results as NO_TYPE, to avoid unnecessary boxing in boxIfNeeded
3764 if (currentRestype.hasTag(VOID))
3765 currentRestype = Type.noType;
3766 tree.body = tree.getBodyKind() == BodyKind.EXPRESSION ?
3767 translate((JCExpression) tree.body, currentRestype) :
3768 translate(tree.body);
3769 } finally {
3770 currentRestype = prevRestype;
3771 }
3772 result = tree;
3773 }
3774
3775 public void visitSwitch(JCSwitch tree) {
3776 List<JCCase> cases = tree.patternSwitch ? addDefaultIfNeeded(tree.patternSwitch,
3777 tree.wasEnumSelector,
3778 tree.cases)
3779 : tree.cases;
3780 handleSwitch(tree, tree.selector, cases);
3781 }
3782
3783 @Override
3784 public void visitSwitchExpression(JCSwitchExpression tree) {
3785 List<JCCase> cases = addDefaultIfNeeded(tree.patternSwitch, tree.wasEnumSelector, tree.cases);
3786 handleSwitch(tree, tree.selector, cases);
3787 }
3788
3789 private List<JCCase> addDefaultIfNeeded(boolean patternSwitch, boolean wasEnumSelector,
3790 List<JCCase> cases) {
3791 if (cases.stream().flatMap(c -> c.labels.stream()).noneMatch(p -> p.hasTag(Tag.DEFAULTCASELABEL))) {
3792 boolean matchException = useMatchException;
3793 matchException |= patternSwitch && !wasEnumSelector;
3794 Type exception = matchException ? syms.matchExceptionType
3795 : syms.incompatibleClassChangeErrorType;
3796 List<JCExpression> params = matchException ? List.of(makeNull(), makeNull())
3797 : List.nil();
3798 JCThrow thr = make.Throw(makeNewClass(exception, params));
3799 JCCase c = make.Case(JCCase.STATEMENT, List.of(make.DefaultCaseLabel()), null, List.of(thr), null);
3800 cases = cases.prepend(c);
3801 }
3802
3803 return cases;
3804 }
3805
3806 private void handleSwitch(JCTree tree, JCExpression selector, List<JCCase> cases) {
3807 //expand multiple label cases:
3808 ListBuffer<JCCase> convertedCases = new ListBuffer<>();
3809
3810 for (JCCase c : cases) {
3811 switch (c.labels.size()) {
3812 case 0: //default
3813 case 1: //single label
3814 convertedCases.append(c);
3815 break;
3816 default: //multiple labels, expand:
3817 //case C1, C2, C3: ...
3818 //=>
3819 //case C1:
3820 //case C2:
3821 //case C3: ...
3822 List<JCCaseLabel> patterns = c.labels;
3823 while (patterns.tail.nonEmpty()) {
3824 convertedCases.append(make_at(c.pos()).Case(JCCase.STATEMENT,
3825 List.of(patterns.head),
3826 null,
3827 List.nil(),
3828 null));
3829 patterns = patterns.tail;
3830 }
3831 c.labels = patterns;
3832 convertedCases.append(c);
3833 break;
3834 }
3835 }
3836
3837 for (JCCase c : convertedCases) {
3838 if (c.caseKind == JCCase.RULE && c.completesNormally) {
3839 JCBreak b = make.at(TreeInfo.endPos(c.stats.last())).Break(null);
3840 b.target = tree;
3841 c.stats = c.stats.append(b);
3842 }
3843 }
3844
3845 cases = convertedCases.toList();
3846
3847 Type selsuper = types.supertype(selector.type);
3848 boolean enumSwitch = selsuper != null &&
3849 (selector.type.tsym.flags() & ENUM) != 0;
3850 boolean stringSwitch = selsuper != null &&
3851 types.isSameType(selector.type, syms.stringType);
3852 boolean boxedSwitch = !enumSwitch && !stringSwitch && !selector.type.isPrimitive();
3853 selector = translate(selector, selector.type);
3854 cases = translateCases(cases);
3855 if (tree.hasTag(SWITCH)) {
3856 ((JCSwitch) tree).selector = selector;
3857 ((JCSwitch) tree).cases = cases;
3858 } else if (tree.hasTag(SWITCH_EXPRESSION)) {
3859 ((JCSwitchExpression) tree).selector = selector;
3860 ((JCSwitchExpression) tree).cases = cases;
3861 } else {
3862 Assert.error();
3863 }
3864 if (enumSwitch) {
3865 result = visitEnumSwitch(tree, selector, cases);
3866 } else if (stringSwitch) {
3867 result = visitStringSwitch(tree, selector, cases);
3868 } else if (boxedSwitch) {
3869 //An switch over boxed primitive. Pattern matching switches are already translated
3870 //by TransPatterns, so all non-primitive types are only boxed primitives:
3871 result = visitBoxedPrimitiveSwitch(tree, selector, cases);
3872 } else {
3873 result = tree;
3874 }
3875 }
3876
3877 public JCTree visitEnumSwitch(JCTree tree, JCExpression selector, List<JCCase> cases) {
3878 TypeSymbol enumSym = selector.type.tsym;
3879 EnumMapping map = mapForEnum(tree.pos(), enumSym);
3880 make_at(tree.pos());
3881 Symbol ordinalMethod = lookupMethod(tree.pos(),
3882 names.ordinal,
3883 selector.type,
3884 List.nil());
3885 JCExpression newSelector;
3886
3887 if (cases.stream().anyMatch(c -> TreeInfo.isNullCaseLabel(c.labels.head))) {
3888 //for enum switches with case null, do:
3889 //switch ($selector != null ? $mapVar[$selector.ordinal()] : -1) {...}
3890 //replacing case null with case -1:
3891 VarSymbol dollar_s = new VarSymbol(FINAL|SYNTHETIC,
3892 names.fromString("s" + variableIndex++ + this.target.syntheticNameChar()),
3893 selector.type,
3894 currentMethodSym);
3895 JCStatement var = make.at(tree.pos()).VarDef(dollar_s, selector).setType(dollar_s.type);
3896 newSelector = map.switchValue(
3897 make.App(make.Select(make.Ident(dollar_s),
3898 ordinalMethod)));
3899 newSelector =
3900 make.LetExpr(List.of(var),
3901 make.Conditional(makeBinary(NE, make.Ident(dollar_s), makeNull()),
3902 newSelector,
3903 makeLit(syms.intType, -1))
3904 .setType(newSelector.type))
3905 .setType(newSelector.type);
3906 } else {
3907 newSelector = map.switchValue(
3908 make.App(make.Select(selector,
3909 ordinalMethod)));
3910 }
3911 ListBuffer<JCCase> newCases = new ListBuffer<>();
3912 for (JCCase c : cases) {
3913 if (c.labels.head.hasTag(CONSTANTCASELABEL)) {
3914 JCExpression pat;
3915 if (TreeInfo.isNullCaseLabel(c.labels.head)) {
3916 pat = makeLit(syms.intType, -1);
3917 } else {
3918 VarSymbol label = (VarSymbol)TreeInfo.symbol(((JCConstantCaseLabel) c.labels.head).expr);
3919 pat = map.caseValue(label);
3920 }
3921 newCases.append(make.Case(JCCase.STATEMENT, List.of(make.ConstantCaseLabel(pat)), null, c.stats, null));
3922 } else {
3923 newCases.append(c);
3924 }
3925 }
3926 JCTree enumSwitch;
3927 if (tree.hasTag(SWITCH)) {
3928 enumSwitch = make.Switch(newSelector, newCases.toList());
3929 } else if (tree.hasTag(SWITCH_EXPRESSION)) {
3930 enumSwitch = make.SwitchExpression(newSelector, newCases.toList());
3931 enumSwitch.setType(tree.type);
3932 } else {
3933 Assert.error();
3934 throw new AssertionError();
3935 }
3936 patchTargets(enumSwitch, tree, enumSwitch);
3937 return enumSwitch;
3938 }
3939
3940 public JCTree visitStringSwitch(JCTree tree, JCExpression selector, List<JCCase> caseList) {
3941 int alternatives = caseList.size();
3942
3943 if (alternatives == 0) { // Strange but legal possibility (only legal for switch statement)
3944 return make.at(tree.pos()).Exec(attr.makeNullCheck(selector));
3945 } else {
3946 /*
3947 * The general approach used is to translate a single
3948 * string switch statement into a series of two chained
3949 * switch statements: the first a synthesized statement
3950 * switching on the argument string's hash value and
3951 * computing a string's position in the list of original
3952 * case labels, if any, followed by a second switch on the
3953 * computed integer value. The second switch has the same
3954 * code structure as the original string switch statement
3955 * except that the string case labels are replaced with
3956 * positional integer constants starting at 0.
3957 *
3958 * The first switch statement can be thought of as an
3959 * inlined map from strings to their position in the case
3960 * label list. An alternate implementation would use an
3961 * actual Map for this purpose, as done for enum switches.
3962 *
3963 * With some additional effort, it would be possible to
3964 * use a single switch statement on the hash code of the
3965 * argument, but care would need to be taken to preserve
3966 * the proper control flow in the presence of hash
3967 * collisions and other complications, such as
3968 * fallthroughs. Switch statements with one or two
3969 * alternatives could also be specially translated into
3970 * if-then statements to omit the computation of the hash
3971 * code.
3972 *
3973 * The generated code assumes that the hashing algorithm
3974 * of String is the same in the compilation environment as
3975 * in the environment the code will run in. The string
3976 * hashing algorithm in the SE JDK has been unchanged
3977 * since at least JDK 1.2. Since the algorithm has been
3978 * specified since that release as well, it is very
3979 * unlikely to be changed in the future.
3980 *
3981 * Different hashing algorithms, such as the length of the
3982 * strings or a perfect hashing algorithm over the
3983 * particular set of case labels, could potentially be
3984 * used instead of String.hashCode.
3985 */
3986
3987 ListBuffer<JCStatement> stmtList = new ListBuffer<>();
3988
3989 // Map from String case labels to their original position in
3990 // the list of case labels.
3991 Map<String, Integer> caseLabelToPosition = new LinkedHashMap<>(alternatives + 1, 1.0f);
3992
3993 // Map of hash codes to the string case labels having that hashCode.
3994 Map<Integer, Set<String>> hashToString = new LinkedHashMap<>(alternatives + 1, 1.0f);
3995
3996 int casePosition = 0;
3997 JCCase nullCase = null;
3998 int nullCaseLabel = -1;
3999
4000 for(JCCase oneCase : caseList) {
4001 if (oneCase.labels.head.hasTag(CONSTANTCASELABEL)) {
4002 if (TreeInfo.isNullCaseLabel(oneCase.labels.head)) {
4003 nullCase = oneCase;
4004 nullCaseLabel = casePosition;
4005 } else {
4006 JCExpression expression = ((JCConstantCaseLabel) oneCase.labels.head).expr;
4007 String labelExpr = (String) expression.type.constValue();
4008 Integer mapping = caseLabelToPosition.put(labelExpr, casePosition);
4009 Assert.checkNull(mapping);
4010 int hashCode = labelExpr.hashCode();
4011
4012 Set<String> stringSet = hashToString.get(hashCode);
4013 if (stringSet == null) {
4014 stringSet = new LinkedHashSet<>(1, 1.0f);
4015 stringSet.add(labelExpr);
4016 hashToString.put(hashCode, stringSet);
4017 } else {
4018 boolean added = stringSet.add(labelExpr);
4019 Assert.check(added);
4020 }
4021 }
4022 }
4023 casePosition++;
4024 }
4025
4026 // Synthesize a switch statement that has the effect of
4027 // mapping from a string to the integer position of that
4028 // string in the list of case labels. This is done by
4029 // switching on the hashCode of the string followed by an
4030 // if-then-else chain comparing the input for equality
4031 // with all the case labels having that hash value.
4032
4033 /*
4034 * s$ = top of stack;
4035 * tmp$ = -1;
4036 * switch($s.hashCode()) {
4037 * case caseLabel.hashCode:
4038 * if (s$.equals("caseLabel_1")
4039 * tmp$ = caseLabelToPosition("caseLabel_1");
4040 * else if (s$.equals("caseLabel_2"))
4041 * tmp$ = caseLabelToPosition("caseLabel_2");
4042 * ...
4043 * break;
4044 * ...
4045 * }
4046 */
4047
4048 VarSymbol dollar_s = new VarSymbol(FINAL|SYNTHETIC,
4049 names.fromString("s" + variableIndex++ + target.syntheticNameChar()),
4050 syms.stringType,
4051 currentMethodSym);
4052 stmtList.append(make.at(tree.pos()).VarDef(dollar_s, selector).setType(dollar_s.type));
4053
4054 VarSymbol dollar_tmp = new VarSymbol(SYNTHETIC,
4055 names.fromString("tmp" + variableIndex++ + target.syntheticNameChar()),
4056 syms.intType,
4057 currentMethodSym);
4058 JCVariableDecl dollar_tmp_def =
4059 (JCVariableDecl)make.VarDef(dollar_tmp, make.Literal(INT, -1)).setType(dollar_tmp.type);
4060 dollar_tmp_def.init.type = dollar_tmp.type = syms.intType;
4061 stmtList.append(dollar_tmp_def);
4062 ListBuffer<JCCase> caseBuffer = new ListBuffer<>();
4063 // hashCode will trigger nullcheck on original switch expression
4064 JCMethodInvocation hashCodeCall = makeCall(make.Ident(dollar_s),
4065 names.hashCode,
4066 List.nil()).setType(syms.intType);
4067 JCSwitch switch1 = make.Switch(hashCodeCall,
4068 caseBuffer.toList());
4069 for(Map.Entry<Integer, Set<String>> entry : hashToString.entrySet()) {
4070 int hashCode = entry.getKey();
4071 Set<String> stringsWithHashCode = entry.getValue();
4072 Assert.check(stringsWithHashCode.size() >= 1);
4073
4074 JCStatement elsepart = null;
4075 for(String caseLabel : stringsWithHashCode ) {
4076 JCMethodInvocation stringEqualsCall = makeCall(make.Ident(dollar_s),
4077 names.equals,
4078 List.of(make.Literal(caseLabel)));
4079 elsepart = make.If(stringEqualsCall,
4080 make.Exec(make.Assign(make.Ident(dollar_tmp),
4081 make.Literal(caseLabelToPosition.get(caseLabel))).
4082 setType(dollar_tmp.type)),
4083 elsepart);
4084 }
4085
4086 ListBuffer<JCStatement> lb = new ListBuffer<>();
4087 JCBreak breakStmt = make.Break(null);
4088 breakStmt.target = switch1;
4089 lb.append(elsepart).append(breakStmt);
4090
4091 caseBuffer.append(make.Case(JCCase.STATEMENT,
4092 List.of(make.ConstantCaseLabel(make.Literal(hashCode))),
4093 null,
4094 lb.toList(),
4095 null));
4096 }
4097
4098 switch1.cases = caseBuffer.toList();
4099
4100 if (nullCase != null) {
4101 stmtList.append(make.If(makeBinary(NE, make.Ident(dollar_s), makeNull()), switch1, make.Exec(make.Assign(make.Ident(dollar_tmp),
4102 make.Literal(nullCaseLabel)).
4103 setType(dollar_tmp.type))).setType(syms.intType));
4104 } else {
4105 stmtList.append(switch1);
4106 }
4107
4108 // Make isomorphic switch tree replacing string labels
4109 // with corresponding integer ones from the label to
4110 // position map.
4111
4112 ListBuffer<JCCase> lb = new ListBuffer<>();
4113 for(JCCase oneCase : caseList ) {
4114 boolean isDefault = !oneCase.labels.head.hasTag(CONSTANTCASELABEL);
4115 JCExpression caseExpr;
4116 if (isDefault)
4117 caseExpr = null;
4118 else if (oneCase == nullCase) {
4119 caseExpr = make.Literal(nullCaseLabel);
4120 } else {
4121 JCExpression expression = ((JCConstantCaseLabel) oneCase.labels.head).expr;
4122 String name = (String) TreeInfo.skipParens(expression)
4123 .type.constValue();
4124 caseExpr = make.Literal(caseLabelToPosition.get(name));
4125 }
4126
4127 lb.append(make.Case(JCCase.STATEMENT, caseExpr == null ? List.of(make.DefaultCaseLabel())
4128 : List.of(make.ConstantCaseLabel(caseExpr)),
4129 null,
4130 oneCase.stats, null));
4131 }
4132
4133 if (tree.hasTag(SWITCH)) {
4134 JCSwitch switch2 = make.Switch(make.Ident(dollar_tmp), lb.toList());
4135 // Rewire up old unlabeled break statements to the
4136 // replacement switch being created.
4137 patchTargets(switch2, tree, switch2);
4138
4139 stmtList.append(switch2);
4140
4141 JCBlock res = make.Block(0L, stmtList.toList());
4142 res.endpos = TreeInfo.endPos(tree);
4143 return res;
4144 } else {
4145 JCSwitchExpression switch2 = make.SwitchExpression(make.Ident(dollar_tmp), lb.toList());
4146
4147 // Rewire up old unlabeled break statements to the
4148 // replacement switch being created.
4149 patchTargets(switch2, tree, switch2);
4150
4151 switch2.setType(tree.type);
4152
4153 LetExpr res = make.LetExpr(stmtList.toList(), switch2);
4154
4155 res.needsCond = true;
4156 res.setType(tree.type);
4157
4158 return res;
4159 }
4160 }
4161 }
4162
4163 private JCTree visitBoxedPrimitiveSwitch(JCTree tree, JCExpression selector, List<JCCase> cases) {
4164 JCExpression newSelector;
4165
4166 if (cases.stream().anyMatch(c -> TreeInfo.isNullCaseLabel(c.labels.head))) {
4167 //a switch over a boxed primitive, with a null case. Pick two constants that are
4168 //not used by any branch in the case (c1 and c2), close to other constants that are
4169 //used in the switch. Then do:
4170 //switch ($selector != null ? $selector != c1 ? $selector : c2 : c1) {...}
4171 //replacing case null with case c1
4172 Set<Integer> constants = new LinkedHashSet<>();
4173 JCCase nullCase = null;
4174
4175 for (JCCase c : cases) {
4176 if (TreeInfo.isNullCaseLabel(c.labels.head)) {
4177 nullCase = c;
4178 } else if (!c.labels.head.hasTag(DEFAULTCASELABEL)) {
4179 constants.add((int) ((JCConstantCaseLabel) c.labels.head).expr.type.constValue());
4180 }
4181 }
4182
4183 Assert.checkNonNull(nullCase);
4184
4185 int nullValue = constants.isEmpty() ? 0 : constants.iterator().next();
4186
4187 while (constants.contains(nullValue)) nullValue++;
4188
4189 constants.add(nullValue);
4190 nullCase.labels.head = make.ConstantCaseLabel(makeLit(syms.intType, nullValue));
4191
4192 int replacementValue = nullValue;
4193
4194 while (constants.contains(replacementValue)) replacementValue++;
4195
4196 VarSymbol dollar_s = new VarSymbol(FINAL|SYNTHETIC,
4197 names.fromString("s" + variableIndex++ + this.target.syntheticNameChar()),
4198 selector.type,
4199 currentMethodSym);
4200 JCStatement var = make.at(tree.pos()).VarDef(dollar_s, selector).setType(dollar_s.type);
4201 JCExpression nullValueReplacement =
4202 make.Conditional(makeBinary(NE,
4203 unbox(make.Ident(dollar_s), syms.intType),
4204 makeLit(syms.intType, nullValue)),
4205 unbox(make.Ident(dollar_s), syms.intType),
4206 makeLit(syms.intType, replacementValue))
4207 .setType(syms.intType);
4208 JCExpression nullCheck =
4209 make.Conditional(makeBinary(NE, make.Ident(dollar_s), makeNull()),
4210 nullValueReplacement,
4211 makeLit(syms.intType, nullValue))
4212 .setType(syms.intType);
4213 newSelector = make.LetExpr(List.of(var), nullCheck).setType(syms.intType);
4214 } else {
4215 newSelector = unbox(selector, syms.intType);
4216 }
4217
4218 if (tree.hasTag(SWITCH)) {
4219 ((JCSwitch) tree).selector = newSelector;
4220 } else {
4221 ((JCSwitchExpression) tree).selector = newSelector;
4222 }
4223
4224 return tree;
4225 }
4226
4227 @Override
4228 public void visitBreak(JCBreak tree) {
4229 result = tree;
4230 }
4231
4232 @Override
4233 public void visitYield(JCYield tree) {
4234 tree.value = translate(tree.value, tree.target.type);
4235 result = tree;
4236 }
4237
4238 public void visitNewArray(JCNewArray tree) {
4239 tree.elemtype = translate(tree.elemtype);
4240 for (List<JCExpression> t = tree.dims; t.tail != null; t = t.tail)
4241 if (t.head != null) t.head = translate(t.head, syms.intType);
4242 tree.elems = translate(tree.elems, types.elemtype(tree.type));
4243 result = tree;
4244 }
4245
4246 public void visitSelect(JCFieldAccess tree) {
4247 // need to special case-access of the form C.super.x
4248 // these will always need an access method, unless C
4249 // is a default interface subclassed by the current class.
4250 boolean qualifiedSuperAccess =
4251 tree.selected.hasTag(SELECT) &&
4252 TreeInfo.name(tree.selected) == names._super &&
4253 !types.isDirectSuperInterface(((JCFieldAccess)tree.selected).selected.type.tsym, currentClass);
4254 tree.selected = translate(tree.selected);
4255 if (tree.name == names._class && tree.selected.type.isPrimitiveOrVoid()) {
4256 result = classOf(tree.selected);
4257 }
4258 else if (tree.name == names._super &&
4259 types.isDirectSuperInterface(tree.selected.type.tsym, currentClass)) {
4260 //default super call!! Not a classic qualified super call
4261 TypeSymbol supSym = tree.selected.type.tsym;
4262 Assert.checkNonNull(types.asSuper(currentClass.type, supSym));
4263 result = tree;
4264 }
4265 else if (tree.name == names._this || tree.name == names._super) {
4266 result = makeThis(tree.pos(), tree.selected.type.tsym);
4267 }
4268 else
4269 result = access(tree.sym, tree, enclOp, qualifiedSuperAccess);
4270 }
4271
4272 public void visitLetExpr(LetExpr tree) {
4273 tree.defs = translate(tree.defs);
4274 tree.expr = translate(tree.expr, tree.type);
4275 result = tree;
4276 }
4277
4278 // There ought to be nothing to rewrite here;
4279 // we don't generate code.
4280 public void visitAnnotation(JCAnnotation tree) {
4281 result = tree;
4282 }
4283
4284 @Override
4285 public void visitTry(JCTry tree) {
4286 if (tree.resources.nonEmpty()) {
4287 result = makeTwrTry(tree);
4288 return;
4289 }
4290
4291 boolean hasBody = tree.body.getStatements().nonEmpty();
4292 boolean hasCatchers = tree.catchers.nonEmpty();
4293 boolean hasFinally = tree.finalizer != null &&
4294 tree.finalizer.getStatements().nonEmpty();
4295
4296 if (!hasCatchers && !hasFinally) {
4297 result = translate(tree.body);
4298 return;
4299 }
4300
4301 if (!hasBody) {
4302 if (hasFinally) {
4303 result = translate(tree.finalizer);
4304 } else {
4305 result = translate(tree.body);
4306 }
4307 return;
4308 }
4309
4310 // no optimizations possible
4311 super.visitTry(tree);
4312 }
4313
4314 /* ************************************************************************
4315 * main method
4316 *************************************************************************/
4317
4318 /** Translate a toplevel class and return a list consisting of
4319 * the translated class and translated versions of all inner classes.
4320 * @param env The attribution environment current at the class definition.
4321 * We need this for resolving some additional symbols.
4322 * @param cdef The tree representing the class definition.
4323 */
4324 public List<JCTree> translateTopLevelClass(Env<AttrContext> env, JCTree cdef, TreeMaker make) {
4325 ListBuffer<JCTree> translated = null;
4326 try {
4327 attrEnv = env;
4328 this.make = make;
4329 endPosTable = env.toplevel.endPositions;
4330 currentClass = null;
4331 currentRestype = null;
4332 currentMethodDef = null;
4333 outermostClassDef = (cdef.hasTag(CLASSDEF)) ? (JCClassDecl)cdef : null;
4334 outermostMemberDef = null;
4335 this.translated = new ListBuffer<>();
4336 classdefs = new HashMap<>();
4337 actualSymbols = new HashMap<>();
4338 freevarCache = new HashMap<>();
4339 proxies = new HashMap<>();
4340 twrVars = WriteableScope.create(syms.noSymbol);
4341 outerThisStack = List.nil();
4342 accessNums = new HashMap<>();
4343 accessSyms = new HashMap<>();
4344 accessConstrs = new HashMap<>();
4345 accessConstrTags = List.nil();
4346 accessed = new ListBuffer<>();
4347 translate(cdef, (JCExpression)null);
4348 for (List<Symbol> l = accessed.toList(); l.nonEmpty(); l = l.tail)
4349 makeAccessible(l.head);
4350 for (EnumMapping map : enumSwitchMap.values())
4351 map.translate();
4352 checkConflicts(this.translated.toList());
4353 checkAccessConstructorTags();
4354 translated = this.translated;
4355 } finally {
4356 // note that recursive invocations of this method fail hard
4357 attrEnv = null;
4358 this.make = null;
4359 endPosTable = null;
4360 currentClass = null;
4361 currentRestype = null;
4362 currentMethodDef = null;
4363 outermostClassDef = null;
4364 outermostMemberDef = null;
4365 this.translated = null;
4366 classdefs = null;
4367 actualSymbols = null;
4368 freevarCache = null;
4369 proxies = null;
4370 outerThisStack = null;
4371 accessNums = null;
4372 accessSyms = null;
4373 accessConstrs = null;
4374 accessConstrTags = null;
4375 accessed = null;
4376 enumSwitchMap.clear();
4377 assertionsDisabledClassCache = null;
4378 }
4379 return translated.toList();
4380 }
4381
4382 // needed for the lambda deserialization method, which is expressed as a big switch on strings
4383 public JCMethodDecl translateMethod(Env<AttrContext> env, JCMethodDecl methodDecl, TreeMaker make) {
4384 try {
4385 this.attrEnv = env;
4386 this.make = make;
4387 this.currentClass = methodDecl.sym.enclClass();
4388 proxies = new HashMap<>();
4389 return translate(methodDecl);
4390 } finally {
4391 this.attrEnv = null;
4392 this.make = null;
4393 this.currentClass = null;
4394 // the two fields below are set when visiting the method
4395 this.currentMethodSym = null;
4396 this.currentMethodDef = null;
4397 this.proxies = null;
4398 }
4399 }
4400 }