1 /*
2 * Copyright (c) 1999, 2026, 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.tree.*;
40 import com.sun.tools.javac.util.*;
41 import com.sun.tools.javac.util.JCDiagnostic.DiagnosticPosition;
42 import com.sun.tools.javac.util.List;
43
44 import com.sun.tools.javac.code.Symbol.*;
45 import com.sun.tools.javac.code.Symbol.OperatorSymbol.AccessCode;
46 import com.sun.tools.javac.resources.CompilerProperties.Errors;
47 import com.sun.tools.javac.tree.JCTree.*;
48 import com.sun.tools.javac.code.Type.*;
49
50 import com.sun.tools.javac.jvm.Target;
51
52 import static com.sun.tools.javac.code.Flags.*;
53 import static com.sun.tools.javac.code.Flags.BLOCK;
54 import static com.sun.tools.javac.code.Scope.LookupKind.NON_RECURSIVE;
55 import static com.sun.tools.javac.code.TypeTag.*;
56 import static com.sun.tools.javac.code.Kinds.Kind.*;
57 import com.sun.tools.javac.code.Source.Feature;
58 import static com.sun.tools.javac.jvm.ByteCodes.*;
59 import com.sun.tools.javac.tree.JCTree.JCBreak;
60 import com.sun.tools.javac.tree.JCTree.JCCase;
61 import com.sun.tools.javac.tree.JCTree.JCExpression;
62 import com.sun.tools.javac.tree.JCTree.JCExpressionStatement;
63
64 import static com.sun.tools.javac.tree.JCTree.JCOperatorExpression.OperandPos.LEFT;
65 import com.sun.tools.javac.tree.JCTree.JCSwitchExpression;
66
67 import static com.sun.tools.javac.tree.JCTree.Tag.*;
68
69 /** This pass translates away some syntactic sugar: inner classes,
70 * class literals, assertions, foreach loops, etc.
71 *
72 * <p><b>This is NOT part of any supported API.
73 * If you write code that depends on this, you do so at your own risk.
74 * This code and its internal interfaces are subject to change or
75 * deletion without notice.</b>
76 */
77 public class Lower extends TreeTranslator {
78 protected static final Context.Key<Lower> lowerKey = new Context.Key<>();
79
80 public static Lower instance(Context context) {
81 Lower instance = context.get(lowerKey);
82 if (instance == null)
83 instance = new Lower(context);
84 return instance;
85 }
86
87 private final Names names;
88 private final Log log;
89 private final Symtab syms;
90 private final Resolve rs;
91 private final Operators operators;
92 private final Check chk;
93 private final Attr attr;
94 private TreeMaker make;
95 private DiagnosticPosition make_pos;
96 private final ConstFold cfolder;
97 private final Target target;
98 private final TypeEnvs typeEnvs;
99 private final Name dollarAssertionsDisabled;
100 private final Types types;
101 private final TransTypes transTypes;
102 private final boolean debugLower;
103 private final boolean disableProtectedAccessors; // experimental
104 private final PkgInfo pkginfoOpt;
105 private final boolean optimizeOuterThis;
106 private final boolean nullCheckOuterThis;
107 private final boolean useMatchException;
108 private final HashMap<TypePairs, String> typePairToName;
109 private final boolean allowValueClasses;
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 nullCheckOuterThis = options.getBoolean("nullCheckOuterThis",
138 target.nullCheckOuterThisByDefault());
139 disableProtectedAccessors = options.isSet("disableProtectedAccessors");
140 Source source = Source.instance(context);
141 Preview preview = Preview.instance(context);
142 useMatchException = Feature.PATTERN_SWITCH.allowedInSource(source) &&
143 (preview.isEnabled() || !preview.isPreview(Feature.PATTERN_SWITCH));
144 typePairToName = TypePairs.initialize(syms);
145 this.allowValueClasses = (!preview.isPreview(Feature.VALUE_CLASSES) || preview.isEnabled()) &&
146 Feature.VALUE_CLASSES.allowedInSource(source);
147 }
148
149 /** The currently enclosing class.
150 */
151 ClassSymbol currentClass;
152
153 /** A queue of all translated classes.
154 */
155 ListBuffer<JCTree> translated;
156
157 /** Environment for symbol lookup, set by translateTopLevelClass.
158 */
159 Env<AttrContext> attrEnv;
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 hash table mapping local classes to a set of outer this fields
200 */
201 public Map<ClassSymbol, Set<JCExpression>> initializerOuterThis = new WeakHashMap<>();
202
203 /** A navigator class for assembling a mapping from local class symbols
204 * to class definition trees.
205 * There is only one case; all other cases simply traverse down the tree.
206 */
207 class ClassMap extends TreeScanner {
208
209 /** All encountered class defs are entered into classdefs table.
210 */
211 public void visitClassDef(JCClassDecl tree) {
212 classdefs.put(tree.sym, tree);
213 super.visitClassDef(tree);
214 }
215 }
216 ClassMap classMap = new ClassMap();
217
218 /** Map a class symbol to its definition.
219 * @param c The class symbol of which we want to determine the definition.
220 */
221 JCClassDecl classDef(ClassSymbol c) {
222 // First lookup the class in the classdefs table.
223 JCClassDecl def = classdefs.get(c);
224 if (def == null && outermostMemberDef != null) {
225 // If this fails, traverse outermost member definition, entering all
226 // local classes into classdefs, and try again.
227 classMap.scan(outermostMemberDef);
228 def = classdefs.get(c);
229 }
230 if (def == null) {
231 // If this fails, traverse outermost class definition, entering all
232 // local classes into classdefs, and try again.
233 classMap.scan(outermostClassDef);
234 def = classdefs.get(c);
235 }
236 return def;
237 }
238
239 /**
240 * Get the enum constants for the given enum class symbol, if known.
241 * They will only be found if they are defined within the same top-level
242 * class as the class being compiled, so it's safe to assume that they
243 * can't change at runtime due to a recompilation.
244 */
245 List<Name> enumNamesFor(ClassSymbol c) {
246
247 // Find the class definition and verify it is an enum class
248 final JCClassDecl classDef = classDef(c);
249 if (classDef == null ||
250 (classDef.mods.flags & ENUM) == 0 ||
251 (types.supertype(currentClass.type).tsym.flags() & ENUM) != 0) {
252 return null;
253 }
254
255 // Gather the enum identifiers
256 ListBuffer<Name> idents = new ListBuffer<>();
257 for (List<JCTree> defs = classDef.defs; defs.nonEmpty(); defs=defs.tail) {
258 if (defs.head.hasTag(VARDEF) &&
259 (((JCVariableDecl) defs.head).mods.flags & ENUM) != 0) {
260 JCVariableDecl var = (JCVariableDecl)defs.head;
261 idents.append(var.name);
262 }
263 }
264 return idents.toList();
265 }
266
267 /** A hash table mapping class symbols to lists of free variables.
268 * accessed by them. Only free variables of the method immediately containing
269 * a class are associated with that class.
270 */
271 Map<ClassSymbol,List<VarSymbol>> freevarCache;
272
273 /** A navigator class for collecting the free variables accessed
274 * from a local class.
275 */
276 class FreeVarCollector extends CaptureScanner {
277
278 FreeVarCollector(JCTree ownerTree) {
279 super(ownerTree);
280 }
281
282 void addFreeVars(ClassSymbol c) {
283 List<VarSymbol> fvs = freevarCache.get(c);
284 if (fvs != null) {
285 for (List<VarSymbol> l = fvs; l.nonEmpty(); l = l.tail) {
286 addFreeVar(l.head);
287 }
288 }
289 }
290
291 /** If tree refers to a class instance creation expression
292 * add all free variables of the freshly created class.
293 */
294 public void visitNewClass(JCNewClass tree) {
295 ClassSymbol c = (ClassSymbol)tree.constructor.owner;
296 addFreeVars(c);
297 super.visitNewClass(tree);
298 }
299
300 /** If tree refers to a superclass constructor call,
301 * add all free variables of the superclass.
302 */
303 public void visitApply(JCMethodInvocation tree) {
304 if (TreeInfo.name(tree.meth) == names._super) {
305 addFreeVars((ClassSymbol) TreeInfo.symbol(tree.meth).owner);
306 }
307 super.visitApply(tree);
308 }
309 }
310
311 /** Return the variables accessed from within a local class, which
312 * are declared in the local class' owner.
313 * (in reverse order of first access).
314 */
315 List<VarSymbol> freevars(ClassSymbol c) {
316 List<VarSymbol> fvs = freevarCache.get(c);
317 if (fvs != null) {
318 return fvs;
319 }
320 FreeVarCollector collector = new FreeVarCollector(classDef(c));
321 fvs = collector.analyzeCaptures().reverse();
322 freevarCache.put(c, fvs);
323 return fvs;
324 }
325
326 Map<TypeSymbol,EnumMapping> enumSwitchMap = new LinkedHashMap<>();
327
328 EnumMapping mapForEnum(DiagnosticPosition pos, TypeSymbol enumClass) {
329
330 // If enum class is part of this compilation, just switch on ordinal value
331 if (enumClass.kind == TYP) {
332 final List<Name> idents = enumNamesFor((ClassSymbol)enumClass);
333 if (idents != null)
334 return new CompileTimeEnumMapping(idents);
335 }
336
337 // Map identifiers to ordinal values at runtime, and then switch on that
338 return enumSwitchMap.computeIfAbsent(enumClass, ec -> new RuntimeEnumMapping(pos, ec));
339 }
340
341 /** Generates a test value and corresponding cases for a switch on an enum type.
342 */
343 interface EnumMapping {
344
345 /** Given an expression for the enum value's ordinal, generate an expression for the switch statement.
346 */
347 JCExpression switchValue(JCExpression ordinalExpr);
348
349 /** Generate the switch statement case value corresponding to the given enum value.
350 */
351 JCLiteral caseValue(VarSymbol v);
352
353 default void translate() {
354 }
355 }
356
357 /** EnumMapping using compile-time constants. Only valid when compiling the enum class itself,
358 * because otherwise the ordinals we use could become obsolete if/when the enum class is recompiled.
359 */
360 class CompileTimeEnumMapping implements EnumMapping {
361
362 final List<Name> enumNames;
363
364 CompileTimeEnumMapping(List<Name> enumNames) {
365 Assert.check(enumNames != null);
366 this.enumNames = enumNames;
367 }
368
369 @Override
370 public JCExpression switchValue(JCExpression ordinalExpr) {
371 return ordinalExpr;
372 }
373
374 @Override
375 public JCLiteral caseValue(VarSymbol v) {
376 final int ordinal = enumNames.indexOf(v.name);
377 Assert.check(ordinal != -1);
378 return make.Literal(ordinal);
379 }
380 }
381
382 /** EnumMapping using run-time ordinal lookup.
383 *
384 * This builds a translation table to be used for enum switches.
385 *
386 * <p>For each enum that appears as the type of a switch
387 * expression, we maintain an EnumMapping to assist in the
388 * translation, as exemplified by the following example:
389 *
390 * <p>we translate
391 * <pre>
392 * switch(colorExpression) {
393 * case red: stmt1;
394 * case green: stmt2;
395 * }
396 * </pre>
397 * into
398 * <pre>
399 * switch(Outer$0.$EnumMap$Color[colorExpression.ordinal()]) {
400 * case 1: stmt1;
401 * case 2: stmt2
402 * }
403 * </pre>
404 * with the auxiliary table initialized as follows:
405 * <pre>
406 * class Outer$0 {
407 * synthetic final int[] $EnumMap$Color = new int[Color.values().length];
408 * static {
409 * try { $EnumMap$Color[red.ordinal()] = 1; } catch (NoSuchFieldError ex) {}
410 * try { $EnumMap$Color[green.ordinal()] = 2; } catch (NoSuchFieldError ex) {}
411 * }
412 * }
413 * </pre>
414 * class EnumMapping provides mapping data and support methods for this translation.
415 */
416 class RuntimeEnumMapping implements EnumMapping {
417 RuntimeEnumMapping(DiagnosticPosition pos, TypeSymbol forEnum) {
418 this.forEnum = forEnum;
419 this.values = new LinkedHashMap<>();
420 this.pos = pos;
421 Name varName = names
422 .fromString(target.syntheticNameChar() +
423 "SwitchMap" +
424 target.syntheticNameChar() +
425 ClassWriter.externalize(forEnum.type.tsym.flatName().toString())
426 .replace('/', '.')
427 .replace('.', target.syntheticNameChar()));
428 ClassSymbol outerCacheClass = outerCacheClass();
429 this.mapVar = new VarSymbol(STATIC | SYNTHETIC | FINAL,
430 varName,
431 new ArrayType(syms.intType, syms.arrayClass),
432 outerCacheClass);
433 enterSynthetic(pos, mapVar, outerCacheClass.members());
434 }
435
436 DiagnosticPosition pos = null;
437
438 // the next value to use
439 int next = 1; // 0 (unused map elements) go to the default label
440
441 // the enum for which this is a map
442 final TypeSymbol forEnum;
443
444 // the field containing the map
445 final VarSymbol mapVar;
446
447 // the mapped values
448 final Map<VarSymbol,Integer> values;
449
450 @Override
451 public JCExpression switchValue(JCExpression ordinalExpr) {
452 return make.Indexed(mapVar, ordinalExpr);
453 }
454
455 @Override
456 public JCLiteral caseValue(VarSymbol v) {
457 Integer result = values.get(v);
458 if (result == null)
459 values.put(v, result = next++);
460 return make.Literal(result);
461 }
462
463 // generate the field initializer for the map
464 @Override
465 public void translate() {
466 boolean prevAllowProtectedAccess = attrEnv.info.allowProtectedAccess;
467 try {
468 make.at(pos.getStartPosition());
469 attrEnv.info.allowProtectedAccess = true;
470 JCClassDecl owner = classDef((ClassSymbol)mapVar.owner);
471
472 // synthetic static final int[] $SwitchMap$Color = new int[Color.values().length];
473 MethodSymbol valuesMethod = lookupMethod(pos,
474 names.values,
475 forEnum.type,
476 List.nil());
477 JCExpression size = make // Color.values().length
478 .Select(make.App(make.QualIdent(valuesMethod)),
479 syms.lengthVar);
480 JCExpression mapVarInit = make
481 .NewArray(make.Type(syms.intType), List.of(size), null)
482 .setType(new ArrayType(syms.intType, syms.arrayClass));
483
484 // try { $SwitchMap$Color[red.ordinal()] = 1; } catch (java.lang.NoSuchFieldError ex) {}
485 ListBuffer<JCStatement> stmts = new ListBuffer<>();
486 Symbol ordinalMethod = lookupMethod(pos,
487 names.ordinal,
488 forEnum.type,
489 List.nil());
490 List<JCCatch> catcher = List.<JCCatch>nil()
491 .prepend(make.Catch(make.VarDef(new VarSymbol(PARAMETER, names.ex,
492 syms.noSuchFieldErrorType,
493 syms.noSymbol),
494 null),
495 make.Block(0, List.nil())));
496 for (Map.Entry<VarSymbol,Integer> e : values.entrySet()) {
497 VarSymbol enumerator = e.getKey();
498 Integer mappedValue = e.getValue();
499 JCExpression assign = make
500 .Assign(make.Indexed(mapVar,
501 make.App(make.Select(make.QualIdent(enumerator),
502 ordinalMethod))),
503 make.Literal(mappedValue))
504 .setType(syms.intType);
505 JCStatement exec = make.Exec(assign);
506 JCStatement _try = make.Try(make.Block(0, List.of(exec)), catcher, null);
507 stmts.append(_try);
508 }
509
510 owner.defs = owner.defs
511 .prepend(make.Block(STATIC, stmts.toList()))
512 .prepend(make.VarDef(mapVar, mapVarInit));
513 } finally {
514 attrEnv.info.allowProtectedAccess = prevAllowProtectedAccess;
515 }
516 }
517 }
518
519
520 /* ************************************************************************
521 * Tree building blocks
522 *************************************************************************/
523
524 /** Equivalent to make.at(pos.getStartPosition()) with side effect of caching
525 * pos as make_pos, for use in diagnostics.
526 **/
527 TreeMaker make_at(DiagnosticPosition pos) {
528 make_pos = pos;
529 return make.at(pos);
530 }
531
532 /** Make an attributed tree representing a literal. This will be an
533 * Ident node in the case of boolean literals, a Literal node in all
534 * other cases.
535 * @param type The literal's type.
536 * @param value The literal's value.
537 */
538 JCExpression makeLit(Type type, Object value) {
539 return make.Literal(type.getTag(), value).setType(type.constType(value));
540 }
541
542 /** Make an attributed tree representing null.
543 */
544 JCExpression makeNull() {
545 return makeLit(syms.botType, null);
546 }
547
548 /** Make an attributed class instance creation expression.
549 * @param ctype The class type.
550 * @param args The constructor arguments.
551 */
552 JCNewClass makeNewClass(Type ctype, List<JCExpression> args) {
553 JCNewClass tree = make.NewClass(null,
554 null, make.QualIdent(ctype.tsym), args, null);
555 tree.constructor = rs.resolveConstructor(
556 make_pos, attrEnv, ctype, TreeInfo.types(args), List.nil());
557 tree.type = ctype;
558 return tree;
559 }
560
561 /** Make an attributed unary expression.
562 * @param optag The operators tree tag.
563 * @param arg The operator's argument.
564 */
565 JCUnary makeUnary(JCTree.Tag optag, JCExpression arg) {
566 JCUnary tree = make.Unary(optag, arg);
567 tree.operator = operators.resolveUnary(tree, optag, arg.type);
568 tree.type = tree.operator.type.getReturnType();
569 return tree;
570 }
571
572 /** Make an attributed binary expression.
573 * @param optag The operators tree tag.
574 * @param lhs The operator's left argument.
575 * @param rhs The operator's right argument.
576 */
577 JCBinary makeBinary(JCTree.Tag optag, JCExpression lhs, JCExpression rhs) {
578 JCBinary tree = make.Binary(optag, lhs, rhs);
579 tree.operator = operators.resolveBinary(tree, optag, lhs.type, rhs.type);
580 tree.type = tree.operator.type.getReturnType();
581 return tree;
582 }
583
584 /** Make an attributed assignop expression.
585 * @param optag The operators tree tag.
586 * @param lhs The operator's left argument.
587 * @param rhs The operator's right argument.
588 */
589 JCAssignOp makeAssignop(JCTree.Tag optag, JCTree lhs, JCTree rhs) {
590 JCAssignOp tree = make.Assignop(optag, lhs, rhs);
591 tree.operator = operators.resolveBinary(tree, tree.getTag().noAssignOp(), lhs.type, rhs.type);
592 tree.type = lhs.type;
593 return tree;
594 }
595
596 /** Convert tree into string object, unless it has already a
597 * reference type..
598 */
599 JCExpression makeString(JCExpression tree) {
600 if (!tree.type.isPrimitiveOrVoid()) {
601 return tree;
602 } else {
603 Symbol valueOfSym = lookupMethod(tree.pos(),
604 names.valueOf,
605 syms.stringType,
606 List.of(tree.type));
607 return make.App(make.QualIdent(valueOfSym), List.of(tree));
608 }
609 }
610
611 /** Create an empty anonymous class definition and enter and complete
612 * its symbol. Return the class definition's symbol.
613 * and create
614 * @param flags The class symbol's flags
615 * @param owner The class symbol's owner
616 */
617 JCClassDecl makeEmptyClass(long flags, ClassSymbol owner) {
618 return makeEmptyClass(flags, owner, null, true);
619 }
620
621 JCClassDecl makeEmptyClass(long flags, ClassSymbol owner, Name flatname,
622 boolean addToDefs) {
623 // Create class symbol.
624 ClassSymbol c = syms.defineClass(names.empty, owner);
625 if (flatname != null) {
626 c.flatname = flatname;
627 } else {
628 c.flatname = chk.localClassName(c);
629 }
630 c.sourcefile = owner.sourcefile;
631 c.completer = Completer.NULL_COMPLETER;
632 c.members_field = WriteableScope.create(c);
633 c.flags_field = flags;
634 ClassType ctype = (ClassType) c.type;
635 ctype.supertype_field = syms.objectType;
636 ctype.interfaces_field = List.nil();
637
638 JCClassDecl odef = classDef(owner);
639
640 // Enter class symbol in owner scope and compiled table.
641 enterSynthetic(odef.pos(), c, owner.members());
642 chk.putCompiled(c);
643
644 // Create class definition tree.
645 JCClassDecl cdef = make.ClassDef(
646 make.Modifiers(flags), names.empty,
647 List.nil(),
648 null, List.nil(), List.nil());
649 cdef.sym = c;
650 cdef.type = c.type;
651
652 // Append class definition tree to owner's definitions.
653 if (addToDefs) odef.defs = odef.defs.prepend(cdef);
654 return cdef;
655 }
656
657 /* ************************************************************************
658 * Symbol manipulation utilities
659 *************************************************************************/
660
661 /** Enter a synthetic symbol in a given scope, but complain if there was already one there.
662 * @param pos Position for error reporting.
663 * @param sym The symbol.
664 * @param s The scope.
665 */
666 private void enterSynthetic(DiagnosticPosition pos, Symbol sym, WriteableScope s) {
667 s.enter(sym);
668 }
669
670 /** Create a fresh synthetic name within a given scope - the unique name is
671 * obtained by appending '$' chars at the end of the name until no match
672 * is found.
673 *
674 * @param name base name
675 * @param s scope in which the name has to be unique
676 * @return fresh synthetic name
677 */
678 private Name makeSyntheticName(Name name, Scope s) {
679 do {
680 name = name.append(
681 target.syntheticNameChar(),
682 names.empty);
683 } while (lookupSynthetic(name, s) != null);
684 return name;
685 }
686
687 /** Check whether synthetic symbols generated during lowering conflict
688 * with user-defined symbols.
689 *
690 * @param translatedTrees lowered class trees
691 */
692 void checkConflicts(List<JCTree> translatedTrees) {
693 for (JCTree t : translatedTrees) {
694 t.accept(conflictsChecker);
695 }
696 }
697
698 JCTree.Visitor conflictsChecker = new TreeScanner() {
699
700 TypeSymbol currentClass;
701
702 @Override
703 public void visitMethodDef(JCMethodDecl that) {
704 checkConflicts(that.pos(), that.sym, currentClass);
705 super.visitMethodDef(that);
706 }
707
708 @Override
709 public void visitVarDef(JCVariableDecl that) {
710 if (that.sym.owner.kind == TYP) {
711 checkConflicts(that.pos(), that.sym, currentClass);
712 }
713 super.visitVarDef(that);
714 }
715
716 @Override
717 public void visitClassDef(JCClassDecl that) {
718 TypeSymbol prevCurrentClass = currentClass;
719 currentClass = that.sym;
720 try {
721 super.visitClassDef(that);
722 }
723 finally {
724 currentClass = prevCurrentClass;
725 }
726 }
727
728 void checkConflicts(DiagnosticPosition pos, Symbol sym, TypeSymbol c) {
729 for (Type ct = c.type; ct != Type.noType ; ct = types.supertype(ct)) {
730 for (Symbol sym2 : ct.tsym.members().getSymbolsByName(sym.name, NON_RECURSIVE)) {
731 // VM allows methods and variables with differing types
732 if (sym.kind == sym2.kind &&
733 types.isSameType(types.erasure(sym.type), types.erasure(sym2.type)) &&
734 sym != sym2 &&
735 (sym.flags() & Flags.SYNTHETIC) != (sym2.flags() & Flags.SYNTHETIC) &&
736 (sym.flags() & BRIDGE) == 0 && (sym2.flags() & BRIDGE) == 0) {
737 syntheticError(pos, (sym2.flags() & SYNTHETIC) == 0 ? sym2 : sym);
738 return;
739 }
740 }
741 }
742 }
743
744 /** Report a conflict between a user symbol and a synthetic symbol.
745 */
746 private void syntheticError(DiagnosticPosition pos, Symbol sym) {
747 if (!sym.type.isErroneous()) {
748 log.error(pos, Errors.CannotGenerateClass(sym.location(), Fragments.SyntheticNameConflict(sym, sym.location())));
749 }
750 }
751 };
752
753 /** Look up a synthetic name in a given scope.
754 * @param s The scope.
755 * @param name The name.
756 */
757 private Symbol lookupSynthetic(Name name, Scope s) {
758 Symbol sym = s.findFirst(name);
759 return (sym==null || (sym.flags()&SYNTHETIC)==0) ? null : sym;
760 }
761
762 /** Look up a method in a given scope.
763 */
764 private MethodSymbol lookupMethod(DiagnosticPosition pos, Name name, Type qual, List<Type> args) {
765 return rs.resolveInternalMethod(pos, attrEnv, qual, name, args, List.nil());
766 }
767
768 /** Anon inner classes are used as access constructor tags.
769 * accessConstructorTag will use an existing anon class if one is available,
770 * and synthesize a class (with makeEmptyClass) if one is not available.
771 * However, there is a small possibility that an existing class will not
772 * be generated as expected if it is inside a conditional with a constant
773 * expression. If that is found to be the case, create an empty class tree here.
774 */
775 private void checkAccessConstructorTags() {
776 for (List<ClassSymbol> l = accessConstrTags; l.nonEmpty(); l = l.tail) {
777 ClassSymbol c = l.head;
778 if (isTranslatedClassAvailable(c))
779 continue;
780 // Create class definition tree.
781 // IDENTITY_TYPE will be interpreted as ACC_SUPER for older class files so we are fine
782 JCClassDecl cdec = makeEmptyClass(STATIC | SYNTHETIC | IDENTITY_TYPE,
783 c.outermostClass(), c.flatname, false);
784 swapAccessConstructorTag(c, cdec.sym);
785 translated.append(cdec);
786 }
787 }
788 // where
789 private boolean isTranslatedClassAvailable(ClassSymbol c) {
790 for (JCTree tree: translated) {
791 if (tree.hasTag(CLASSDEF)
792 && ((JCClassDecl) tree).sym == c) {
793 return true;
794 }
795 }
796 return false;
797 }
798
799 void swapAccessConstructorTag(ClassSymbol oldCTag, ClassSymbol newCTag) {
800 for (MethodSymbol methodSymbol : accessConstrs.values()) {
801 Assert.check(methodSymbol.type.hasTag(METHOD));
802 MethodType oldMethodType =
803 (MethodType)methodSymbol.type;
804 if (oldMethodType.argtypes.head.tsym == oldCTag)
805 methodSymbol.type =
806 types.createMethodTypeWithParameters(oldMethodType,
807 oldMethodType.getParameterTypes().tail
808 .prepend(newCTag.erasure(types)));
809 }
810 }
811
812 /* ************************************************************************
813 * Access methods
814 *************************************************************************/
815
816 /** A mapping from symbols to their access numbers.
817 */
818 private Map<Symbol,Integer> accessNums;
819
820 /** A mapping from symbols to an array of access symbols, indexed by
821 * access code.
822 */
823 private Map<Symbol,MethodSymbol[]> accessSyms;
824
825 /** A mapping from (constructor) symbols to access constructor symbols.
826 */
827 private Map<Symbol,MethodSymbol> accessConstrs;
828
829 /** A list of all class symbols used for access constructor tags.
830 */
831 private List<ClassSymbol> accessConstrTags;
832
833 /** A queue for all accessed symbols.
834 */
835 private ListBuffer<Symbol> accessed;
836
837 /** return access code for identifier,
838 * @param tree The tree representing the identifier use.
839 * @param enclOp The closest enclosing operation node of tree,
840 * null if tree is not a subtree of an operation.
841 */
842 private static int accessCode(JCTree tree, JCTree enclOp) {
843 if (enclOp == null)
844 return AccessCode.DEREF.code;
845 else if (enclOp.hasTag(ASSIGN) &&
846 tree == TreeInfo.skipParens(((JCAssign) enclOp).lhs))
847 return AccessCode.ASSIGN.code;
848 else if ((enclOp.getTag().isIncOrDecUnaryOp() || enclOp.getTag().isAssignop()) &&
849 tree == TreeInfo.skipParens(((JCOperatorExpression) enclOp).getOperand(LEFT)))
850 return (((JCOperatorExpression) enclOp).operator).getAccessCode(enclOp.getTag());
851 else
852 return AccessCode.DEREF.code;
853 }
854
855 /** Return binary operator that corresponds to given access code.
856 */
857 private OperatorSymbol binaryAccessOperator(int acode, Tag tag) {
858 return operators.lookupBinaryOp(op -> op.getAccessCode(tag) == acode);
859 }
860
861 /** Return tree tag for assignment operation corresponding
862 * to given binary operator.
863 */
864 private static JCTree.Tag treeTag(OperatorSymbol operator) {
865 switch (operator.opcode) {
866 case ByteCodes.ior: case ByteCodes.lor:
867 return BITOR_ASG;
868 case ByteCodes.ixor: case ByteCodes.lxor:
869 return BITXOR_ASG;
870 case ByteCodes.iand: case ByteCodes.land:
871 return BITAND_ASG;
872 case ByteCodes.ishl: case ByteCodes.lshl:
873 case ByteCodes.ishll: case ByteCodes.lshll:
874 return SL_ASG;
875 case ByteCodes.ishr: case ByteCodes.lshr:
876 case ByteCodes.ishrl: case ByteCodes.lshrl:
877 return SR_ASG;
878 case ByteCodes.iushr: case ByteCodes.lushr:
879 case ByteCodes.iushrl: case ByteCodes.lushrl:
880 return USR_ASG;
881 case ByteCodes.iadd: case ByteCodes.ladd:
882 case ByteCodes.fadd: case ByteCodes.dadd:
883 case ByteCodes.string_add:
884 return PLUS_ASG;
885 case ByteCodes.isub: case ByteCodes.lsub:
886 case ByteCodes.fsub: case ByteCodes.dsub:
887 return MINUS_ASG;
888 case ByteCodes.imul: case ByteCodes.lmul:
889 case ByteCodes.fmul: case ByteCodes.dmul:
890 return MUL_ASG;
891 case ByteCodes.idiv: case ByteCodes.ldiv:
892 case ByteCodes.fdiv: case ByteCodes.ddiv:
893 return DIV_ASG;
894 case ByteCodes.imod: case ByteCodes.lmod:
895 case ByteCodes.fmod: case ByteCodes.dmod:
896 return MOD_ASG;
897 default:
898 throw new AssertionError();
899 }
900 }
901
902 /** The name of the access method with number `anum' and access code `acode'.
903 */
904 Name accessName(int anum, int acode) {
905 return names.fromString(
906 "access" + target.syntheticNameChar() + anum + acode / 10 + acode % 10);
907 }
908
909 /** Return access symbol for a private or protected symbol from an inner class.
910 * @param sym The accessed private symbol.
911 * @param tree The accessing tree.
912 * @param enclOp The closest enclosing operation node of tree,
913 * null if tree is not a subtree of an operation.
914 * @param protAccess Is access to a protected symbol in another
915 * package?
916 * @param refSuper Is access via a (qualified) C.super?
917 */
918 MethodSymbol accessSymbol(Symbol sym, JCTree tree, JCTree enclOp,
919 boolean protAccess, boolean refSuper) {
920 ClassSymbol accOwner = refSuper && protAccess
921 // For access via qualified super (T.super.x), place the
922 // access symbol on T.
923 ? (ClassSymbol)((JCFieldAccess) tree).selected.type.tsym
924 // Otherwise pretend that the owner of an accessed
925 // protected symbol is the enclosing class of the current
926 // class which is a subclass of the symbol's owner.
927 : accessClass(sym, protAccess, tree);
928
929 Symbol vsym = sym;
930 if (sym.owner != accOwner) {
931 vsym = sym.clone(accOwner);
932 actualSymbols.put(vsym, sym);
933 }
934
935 Integer anum // The access number of the access method.
936 = accessNums.get(vsym);
937 if (anum == null) {
938 anum = accessed.length();
939 accessNums.put(vsym, anum);
940 accessSyms.put(vsym, new MethodSymbol[AccessCode.numberOfAccessCodes]);
941 accessed.append(vsym);
942 // System.out.println("accessing " + vsym + " in " + vsym.location());
943 }
944
945 int acode; // The access code of the access method.
946 List<Type> argtypes; // The argument types of the access method.
947 Type restype; // The result type of the access method.
948 List<Type> thrown; // The thrown exceptions of the access method.
949 switch (vsym.kind) {
950 case VAR:
951 acode = accessCode(tree, enclOp);
952 if (acode >= AccessCode.FIRSTASGOP.code) {
953 OperatorSymbol operator = binaryAccessOperator(acode, enclOp.getTag());
954 if (operator.opcode == string_add)
955 argtypes = List.of(syms.objectType);
956 else
957 argtypes = operator.type.getParameterTypes().tail;
958 } else if (acode == AccessCode.ASSIGN.code)
959 argtypes = List.of(vsym.erasure(types));
960 else
961 argtypes = List.nil();
962 restype = vsym.erasure(types);
963 thrown = List.nil();
964 break;
965 case MTH:
966 acode = AccessCode.DEREF.code;
967 argtypes = vsym.erasure(types).getParameterTypes();
968 restype = vsym.erasure(types).getReturnType();
969 thrown = vsym.type.getThrownTypes();
970 break;
971 default:
972 throw new AssertionError();
973 }
974
975 // For references via qualified super, increment acode by one,
976 // making it odd.
977 if (protAccess && refSuper) acode++;
978
979 // Instance access methods get instance as first parameter.
980 // For protected symbols this needs to be the instance as a member
981 // of the type containing the accessed symbol, not the class
982 // containing the access method.
983 if ((vsym.flags() & STATIC) == 0) {
984 argtypes = argtypes.prepend(vsym.owner.erasure(types));
985 }
986 MethodSymbol[] accessors = accessSyms.get(vsym);
987 MethodSymbol accessor = accessors[acode];
988 if (accessor == null) {
989 accessor = new MethodSymbol(
990 STATIC | SYNTHETIC | (accOwner.isInterface() ? PUBLIC : 0),
991 accessName(anum.intValue(), acode),
992 new MethodType(argtypes, restype, thrown, syms.methodClass),
993 accOwner);
994 enterSynthetic(tree.pos(), accessor, accOwner.members());
995 accessors[acode] = accessor;
996 }
997 return accessor;
998 }
999
1000 /** The qualifier to be used for accessing a symbol in an outer class.
1001 * This is either C.sym or C.this.sym, depending on whether or not
1002 * sym is static.
1003 * @param sym The accessed symbol.
1004 */
1005 JCExpression accessBase(DiagnosticPosition pos, Symbol sym) {
1006 return (sym.flags() & STATIC) != 0
1007 ? access(make.at(pos.getStartPosition()).QualIdent(sym.owner))
1008 : makeOwnerThis(pos, sym, true);
1009 }
1010
1011 /** Do we need an access method to reference private symbol?
1012 */
1013 boolean needsPrivateAccess(Symbol sym) {
1014 if (target.hasNestmateAccess()) {
1015 return false;
1016 }
1017 if ((sym.flags() & PRIVATE) == 0 || sym.owner == currentClass) {
1018 return false;
1019 } else if (sym.name == names.init && sym.owner.isDirectlyOrIndirectlyLocal()) {
1020 // private constructor in local class: relax protection
1021 sym.flags_field &= ~PRIVATE;
1022 return false;
1023 } else {
1024 return true;
1025 }
1026 }
1027
1028 /** Do we need an access method to reference symbol in other package?
1029 */
1030 boolean needsProtectedAccess(Symbol sym, JCTree tree) {
1031 if (disableProtectedAccessors) return false;
1032 if ((sym.flags() & PROTECTED) == 0 ||
1033 sym.owner.owner == currentClass.owner || // fast special case
1034 sym.packge() == currentClass.packge())
1035 return false;
1036 if (!currentClass.isSubClass(sym.owner, types))
1037 return true;
1038 if ((sym.flags() & STATIC) != 0 ||
1039 !tree.hasTag(SELECT) ||
1040 TreeInfo.name(((JCFieldAccess) tree).selected) == names._super)
1041 return false;
1042 return !((JCFieldAccess) tree).selected.type.tsym.isSubClass(currentClass, types);
1043 }
1044
1045 /** The class in which an access method for given symbol goes.
1046 * @param sym The access symbol
1047 * @param protAccess Is access to a protected symbol in another
1048 * package?
1049 */
1050 ClassSymbol accessClass(Symbol sym, boolean protAccess, JCTree tree) {
1051 if (protAccess) {
1052 Symbol qualifier = null;
1053 ClassSymbol c = currentClass;
1054 if (tree.hasTag(SELECT) && (sym.flags() & STATIC) == 0) {
1055 qualifier = ((JCFieldAccess) tree).selected.type.tsym;
1056 while (!qualifier.isSubClass(c, types)) {
1057 c = c.owner.enclClass();
1058 }
1059 return c;
1060 } else {
1061 while (!c.isSubClass(sym.owner, types)) {
1062 c = c.owner.enclClass();
1063 }
1064 }
1065 return c;
1066 } else {
1067 // the symbol is private
1068 return sym.owner.enclClass();
1069 }
1070 }
1071
1072 private boolean noClassDefIn(JCTree tree) {
1073 var scanner = new TreeScanner() {
1074 boolean noClassDef = true;
1075 @Override
1076 public void visitClassDef(JCClassDecl tree) {
1077 noClassDef = false;
1078 }
1079 };
1080 scanner.scan(tree);
1081 return scanner.noClassDef;
1082 }
1083
1084 private void addPrunedInfo(JCTree tree) {
1085 List<JCTree> infoList = prunedTree.get(currentClass);
1086 infoList = (infoList == null) ? List.of(tree) : infoList.prepend(tree);
1087 prunedTree.put(currentClass, infoList);
1088 }
1089
1090 /** Ensure that identifier is accessible, return tree accessing the identifier.
1091 * @param sym The accessed symbol.
1092 * @param tree The tree referring to the symbol.
1093 * @param enclOp The closest enclosing operation node of tree,
1094 * null if tree is not a subtree of an operation.
1095 * @param refSuper Is access via a (qualified) C.super?
1096 */
1097 JCExpression access(Symbol sym, JCExpression tree, JCExpression enclOp, boolean refSuper) {
1098 // Access a free variable via its proxy, or its proxy's proxy
1099 while (sym.kind == VAR && sym.owner.kind == MTH &&
1100 sym.owner.enclClass() != currentClass) {
1101 // A constant is replaced by its constant value.
1102 Object cv = ((VarSymbol)sym).getConstValue();
1103 if (cv != null) {
1104 make.at(tree.pos);
1105 return makeLit(sym.type, cv);
1106 }
1107 // Otherwise replace the variable by its proxy.
1108 sym = proxies.get(sym);
1109 Assert.check(sym != null && (sym.flags_field & FINAL) != 0);
1110 tree = make.at(tree.pos).Ident(sym);
1111 }
1112 JCExpression base = (tree.hasTag(SELECT)) ? ((JCFieldAccess) tree).selected : null;
1113 switch (sym.kind) {
1114 case TYP:
1115 if (sym.owner.kind != PCK) {
1116 // Convert type idents to
1117 // <flat name> or <package name> . <flat name>
1118 Name flatname = Convert.shortName(sym.flatName());
1119 while (base != null &&
1120 TreeInfo.symbol(base) != null &&
1121 TreeInfo.symbol(base).kind != PCK) {
1122 base = (base.hasTag(SELECT))
1123 ? ((JCFieldAccess) base).selected
1124 : null;
1125 }
1126 if (tree.hasTag(IDENT)) {
1127 ((JCIdent) tree).name = flatname;
1128 } else if (base == null) {
1129 tree = make.at(tree.pos).Ident(sym);
1130 ((JCIdent) tree).name = flatname;
1131 } else {
1132 ((JCFieldAccess) tree).selected = base;
1133 ((JCFieldAccess) tree).name = flatname;
1134 }
1135 }
1136 break;
1137 case MTH: case VAR:
1138 if (sym.owner.kind == TYP) {
1139
1140 // Access methods are required for
1141 // - private members,
1142 // - protected members in a superclass of an
1143 // enclosing class contained in another package.
1144 // - all non-private members accessed via a qualified super.
1145 boolean protAccess = refSuper && !needsPrivateAccess(sym)
1146 || needsProtectedAccess(sym, tree);
1147 boolean accReq = protAccess || needsPrivateAccess(sym);
1148
1149 // A base has to be supplied for
1150 // - simple identifiers accessing variables in outer classes.
1151 boolean baseReq =
1152 base == null &&
1153 sym.owner != syms.predefClass &&
1154 !sym.isMemberOf(currentClass, types);
1155
1156 if (accReq || baseReq) {
1157 make.at(tree.pos);
1158
1159 // Constants are replaced by their constant value.
1160 if (sym.kind == VAR) {
1161 Object cv = ((VarSymbol)sym).getConstValue();
1162 if (cv != null) {
1163 addPrunedInfo(tree);
1164 return makeLit(sym.type, cv);
1165 }
1166 }
1167
1168 // Private variables and methods are replaced by calls
1169 // to their access methods.
1170 if (accReq) {
1171 List<JCExpression> args = List.nil();
1172 if ((sym.flags() & STATIC) == 0) {
1173 // Instance access methods get instance
1174 // as first parameter.
1175 if (base == null)
1176 base = makeOwnerThis(tree.pos(), sym, true);
1177 args = args.prepend(base);
1178 base = null; // so we don't duplicate code
1179 }
1180 Symbol access = accessSymbol(sym, tree,
1181 enclOp, protAccess,
1182 refSuper);
1183 JCExpression receiver = make.Select(
1184 base != null ? base : make.QualIdent(access.owner),
1185 access);
1186 return make.App(receiver, args);
1187
1188 // Other accesses to members of outer classes get a
1189 // qualifier.
1190 } else if (baseReq) {
1191 return make.at(tree.pos).Select(
1192 accessBase(tree.pos(), sym), sym).setType(tree.type);
1193 }
1194 }
1195 }
1196 }
1197 return tree;
1198 }
1199
1200 /** Ensure that identifier is accessible, return tree accessing the identifier.
1201 * @param tree The identifier tree.
1202 */
1203 JCExpression access(JCExpression tree) {
1204 Symbol sym = TreeInfo.symbol(tree);
1205 return sym == null ? tree : access(sym, tree, null, false);
1206 }
1207
1208 /** Return access constructor for a private constructor,
1209 * or the constructor itself, if no access constructor is needed.
1210 * @param pos The position to report diagnostics, if any.
1211 * @param constr The private constructor.
1212 */
1213 Symbol accessConstructor(DiagnosticPosition pos, Symbol constr) {
1214 if (needsPrivateAccess(constr)) {
1215 ClassSymbol accOwner = constr.owner.enclClass();
1216 MethodSymbol aconstr = accessConstrs.get(constr);
1217 if (aconstr == null) {
1218 List<Type> argtypes = constr.type.getParameterTypes();
1219 if ((accOwner.flags_field & ENUM) != 0)
1220 argtypes = argtypes
1221 .prepend(syms.intType)
1222 .prepend(syms.stringType);
1223 aconstr = new MethodSymbol(
1224 SYNTHETIC,
1225 names.init,
1226 new MethodType(
1227 argtypes.append(
1228 accessConstructorTag().erasure(types)),
1229 constr.type.getReturnType(),
1230 constr.type.getThrownTypes(),
1231 syms.methodClass),
1232 accOwner);
1233 enterSynthetic(pos, aconstr, accOwner.members());
1234 accessConstrs.put(constr, aconstr);
1235 accessed.append(constr);
1236 }
1237 return aconstr;
1238 } else {
1239 return constr;
1240 }
1241 }
1242
1243 /** Return an anonymous class nested in this toplevel class.
1244 */
1245 ClassSymbol accessConstructorTag() {
1246 ClassSymbol topClass = currentClass.outermostClass();
1247 ModuleSymbol topModle = topClass.packge().modle;
1248 for (int i = 1; ; i++) {
1249 Name flatname = names.fromString("" + topClass.getQualifiedName() +
1250 target.syntheticNameChar() +
1251 i);
1252 ClassSymbol ctag = chk.getCompiled(topModle, flatname);
1253 if (ctag == null)
1254 // IDENTITY_TYPE will be interpreted as ACC_SUPER for older class files so we are fine
1255 ctag = makeEmptyClass(STATIC | SYNTHETIC | IDENTITY_TYPE, topClass).sym;
1256 else if (!ctag.isAnonymous())
1257 continue;
1258 // keep a record of all tags, to verify that all are generated as required
1259 accessConstrTags = accessConstrTags.prepend(ctag);
1260 return ctag;
1261 }
1262 }
1263
1264 /** Add all required access methods for a private symbol to enclosing class.
1265 * @param sym The symbol.
1266 */
1267 void makeAccessible(Symbol sym) {
1268 JCClassDecl cdef = classDef(sym.owner.enclClass());
1269 if (cdef == null) Assert.error("class def not found: " + sym + " in " + sym.owner);
1270 if (sym.name == names.init) {
1271 cdef.defs = cdef.defs.prepend(
1272 accessConstructorDef(cdef.pos, sym, accessConstrs.get(sym)));
1273 } else {
1274 MethodSymbol[] accessors = accessSyms.get(sym);
1275 for (int i = 0; i < AccessCode.numberOfAccessCodes; i++) {
1276 if (accessors[i] != null)
1277 cdef.defs = cdef.defs.prepend(
1278 accessDef(cdef.pos, sym, accessors[i], i));
1279 }
1280 }
1281 }
1282
1283 /** Construct definition of an access method.
1284 * @param pos The source code position of the definition.
1285 * @param vsym The private or protected symbol.
1286 * @param accessor The access method for the symbol.
1287 * @param acode The access code.
1288 */
1289 JCTree accessDef(int pos, Symbol vsym, MethodSymbol accessor, int acode) {
1290 // System.err.println("access " + vsym + " with " + accessor);//DEBUG
1291 currentClass = vsym.owner.enclClass();
1292 make.at(pos);
1293 JCMethodDecl md = make.MethodDef(accessor, null);
1294
1295 // Find actual symbol
1296 Symbol sym = actualSymbols.get(vsym);
1297 if (sym == null) sym = vsym;
1298
1299 JCExpression ref; // The tree referencing the private symbol.
1300 List<JCExpression> args; // Any additional arguments to be passed along.
1301 if ((sym.flags() & STATIC) != 0) {
1302 ref = make.Ident(sym);
1303 args = make.Idents(md.params);
1304 } else {
1305 JCExpression site = make.Ident(md.params.head);
1306 if (acode % 2 != 0) {
1307 //odd access codes represent qualified super accesses - need to
1308 //emit reference to the direct superclass, even if the referred
1309 //member is from an indirect superclass (JLS 13.1)
1310 site.setType(types.erasure(types.supertype(vsym.owner.enclClass().type)));
1311 }
1312 ref = make.Select(site, sym);
1313 args = make.Idents(md.params.tail);
1314 }
1315 JCStatement stat; // The statement accessing the private symbol.
1316 if (sym.kind == VAR) {
1317 // Normalize out all odd access codes by taking floor modulo 2:
1318 int acode1 = acode - (acode & 1);
1319
1320 JCExpression expr; // The access method's return value.
1321 AccessCode aCode = AccessCode.getFromCode(acode1);
1322 switch (aCode) {
1323 case DEREF:
1324 expr = ref;
1325 break;
1326 case ASSIGN:
1327 expr = make.Assign(ref, args.head);
1328 break;
1329 case PREINC: case POSTINC: case PREDEC: case POSTDEC:
1330 expr = makeUnary(aCode.tag, ref);
1331 break;
1332 default:
1333 expr = make.Assignop(
1334 treeTag(binaryAccessOperator(acode1, JCTree.Tag.NO_TAG)), ref, args.head);
1335 ((JCAssignOp) expr).operator = binaryAccessOperator(acode1, JCTree.Tag.NO_TAG);
1336 }
1337 stat = make.Return(expr.setType(sym.type));
1338 } else {
1339 stat = make.Call(make.App(ref, args));
1340 }
1341 md.body = make.Block(0, List.of(stat));
1342
1343 // Make sure all parameters, result types and thrown exceptions
1344 // are accessible.
1345 for (List<JCVariableDecl> l = md.params; l.nonEmpty(); l = l.tail)
1346 l.head.vartype = access(l.head.vartype);
1347 md.restype = access(md.restype);
1348 for (List<JCExpression> l = md.thrown; l.nonEmpty(); l = l.tail)
1349 l.head = access(l.head);
1350
1351 return md;
1352 }
1353
1354 /** Construct definition of an access constructor.
1355 * @param pos The source code position of the definition.
1356 * @param constr The private constructor.
1357 * @param accessor The access method for the constructor.
1358 */
1359 JCTree accessConstructorDef(int pos, Symbol constr, MethodSymbol accessor) {
1360 make.at(pos);
1361 JCMethodDecl md = make.MethodDef(accessor,
1362 accessor.externalType(types),
1363 null);
1364 JCIdent callee = make.Ident(names._this);
1365 callee.sym = constr;
1366 callee.type = constr.type;
1367 md.body =
1368 make.Block(0, List.of(
1369 make.Call(
1370 make.App(
1371 callee,
1372 make.Idents(md.params.reverse().tail.reverse())))));
1373 return md;
1374 }
1375
1376 /* ************************************************************************
1377 * Free variables proxies and this$n
1378 *************************************************************************/
1379
1380 /** A map which allows to retrieve the translated proxy variable for any given symbol of an
1381 * enclosing scope that is accessed (the accessed symbol could be the synthetic 'this$n' symbol).
1382 * Inside a constructor, the map temporarily overrides entries corresponding to proxies and any
1383 * 'this$n' symbols, where they represent the constructor parameters.
1384 */
1385 Map<Symbol, Symbol> proxies;
1386
1387 /** A scope containing all unnamed resource variables/saved
1388 * exception variables for translated TWR blocks
1389 */
1390 WriteableScope twrVars;
1391
1392 /** A stack containing the this$n field of the currently translated
1393 * classes (if needed) in innermost first order.
1394 * Inside a constructor, proxies and any this$n symbol are duplicated
1395 * in an additional innermost scope, where they represent the constructor
1396 * parameters.
1397 */
1398 List<VarSymbol> outerThisStack;
1399
1400 /** The name of a free variable proxy.
1401 */
1402 Name proxyName(Name name, int index) {
1403 Name proxyName = names.fromString("val" + target.syntheticNameChar() + name);
1404 if (index > 0) {
1405 proxyName = proxyName.append(names.fromString("" + target.syntheticNameChar() + index));
1406 }
1407 return proxyName;
1408 }
1409
1410 /** Proxy definitions for all free variables in given list, in reverse order.
1411 * @param pos The source code position of the definition.
1412 * @param freevars The free variables.
1413 * @param owner The class in which the definitions go.
1414 * @param additionalFlags Any additional flags
1415 */
1416 List<JCVariableDecl> freevarDefs(int pos, List<VarSymbol> freevars, Symbol owner) {
1417 return freevarDefs(pos, freevars, owner, LOCAL_CAPTURE_FIELD);
1418 }
1419
1420 List<JCVariableDecl> freevarDefs(int pos, List<VarSymbol> freevars, Symbol owner,
1421 long additionalFlags) {
1422 long flags = FINAL | SYNTHETIC | additionalFlags;
1423 List<JCVariableDecl> defs = List.nil();
1424 Set<Name> proxyNames = new HashSet<>();
1425 for (List<VarSymbol> l = freevars; l.nonEmpty(); l = l.tail) {
1426 VarSymbol v = l.head;
1427 int index = 0;
1428 Name proxyName;
1429 do {
1430 proxyName = proxyName(v.name, index++);
1431 } while (!proxyNames.add(proxyName));
1432 VarSymbol proxy = new VarSymbol(
1433 flags, proxyName, v.erasure(types), owner) {
1434 @Override
1435 public Symbol baseSymbol() {
1436 return v;
1437 }
1438 };
1439 proxies.put(v, proxy);
1440 JCVariableDecl vd = make.at(pos).VarDef(proxy, null);
1441 vd.vartype = access(vd.vartype);
1442 defs = defs.prepend(vd);
1443 }
1444 return defs;
1445 }
1446
1447 /** The name of a this$n field
1448 * @param type The class referenced by the this$n field
1449 */
1450 Name outerThisName(Type type, Symbol owner) {
1451 Type t = type.getEnclosingType();
1452 int nestingLevel = 0;
1453 while (t.hasTag(CLASS)) {
1454 t = t.getEnclosingType();
1455 nestingLevel++;
1456 }
1457 Name result = names.fromString("this" + target.syntheticNameChar() + nestingLevel);
1458 while (owner.kind == TYP && ((ClassSymbol)owner).members().findFirst(result) != null)
1459 result = names.fromString(result.toString() + target.syntheticNameChar());
1460 return result;
1461 }
1462
1463 private VarSymbol makeOuterThisVarSymbol(Symbol owner, long flags) {
1464 Type target = owner.innermostAccessibleEnclosingClass().erasure(types);
1465 // Set NOOUTERTHIS for all synthetic outer instance variables, and unset
1466 // it when the variable is accessed. If the variable is never accessed,
1467 // we skip creating an outer instance field and saving the constructor
1468 // parameter to it.
1469 VarSymbol outerThis =
1470 new VarSymbol(flags | NOOUTERTHIS, outerThisName(target, owner), target, owner);
1471 outerThisStack = outerThisStack.prepend(outerThis);
1472 return outerThis;
1473 }
1474
1475 private JCVariableDecl makeOuterThisVarDecl(int pos, VarSymbol sym) {
1476 JCVariableDecl vd = make.at(pos).VarDef(sym, null);
1477 vd.vartype = access(vd.vartype);
1478 return vd;
1479 }
1480
1481 /** Definition for this$n field.
1482 * @param pos The source code position of the definition.
1483 * @param owner The method in which the definition goes.
1484 */
1485 JCVariableDecl outerThisDef(int pos, MethodSymbol owner) {
1486 ClassSymbol c = owner.enclClass();
1487 boolean isMandated =
1488 // Anonymous constructors
1489 (owner.isConstructor() && owner.isAnonymous()) ||
1490 // Constructors of non-private inner member classes
1491 (owner.isConstructor() && c.isInner() &&
1492 !c.isPrivate() && !c.isStatic());
1493 long flags =
1494 FINAL | (isMandated ? MANDATED : SYNTHETIC) | PARAMETER;
1495 VarSymbol outerThis = makeOuterThisVarSymbol(owner, flags);
1496 owner.extraParams = owner.extraParams.prepend(outerThis);
1497 return makeOuterThisVarDecl(pos, outerThis);
1498 }
1499
1500 /** Definition for this$n field.
1501 * @param pos The source code position of the definition.
1502 * @param owner The class in which the definition goes.
1503 */
1504 JCVariableDecl outerThisDef(int pos, ClassSymbol owner) {
1505 VarSymbol outerThis = makeOuterThisVarSymbol(owner, FINAL | SYNTHETIC | (allowValueClasses && owner.isValueClass() ? STRICT : 0));
1506 return makeOuterThisVarDecl(pos, outerThis);
1507 }
1508
1509 /** Return a list of trees that load the free variables in given list,
1510 * in reverse order.
1511 * @param pos The source code position to be used for the trees.
1512 * @param freevars The list of free variables.
1513 */
1514 List<JCExpression> loadFreevars(DiagnosticPosition pos, List<VarSymbol> freevars) {
1515 List<JCExpression> args = List.nil();
1516 for (List<VarSymbol> l = freevars; l.nonEmpty(); l = l.tail)
1517 args = args.prepend(loadFreevar(pos, l.head));
1518 return args;
1519 }
1520 //where
1521 JCExpression loadFreevar(DiagnosticPosition pos, VarSymbol v) {
1522 return access(v, make.at(pos).Ident(v), null, false);
1523 }
1524
1525 /** Construct a tree simulating the expression {@code C.this}.
1526 * @param pos The source code position to be used for the tree.
1527 * @param c The qualifier class.
1528 */
1529 JCExpression makeThis(DiagnosticPosition pos, TypeSymbol c) {
1530 if (currentClass == c) {
1531 // in this case, `this' works fine
1532 return make.at(pos).This(c.erasure(types));
1533 } else {
1534 // need to go via this$n
1535 return makeOuterThis(pos, c);
1536 }
1537 }
1538
1539 /**
1540 * Optionally replace a try statement with the desugaring of a
1541 * try-with-resources statement. The canonical desugaring of
1542 *
1543 * try ResourceSpecification
1544 * Block
1545 *
1546 * is
1547 *
1548 * {
1549 * final VariableModifiers_minus_final R #resource = Expression;
1550 *
1551 * try ResourceSpecificationtail
1552 * Block
1553 * } body-only-finally {
1554 * if (#resource != null) //nullcheck skipped if Expression is provably non-null
1555 * #resource.close();
1556 * } catch (Throwable #primaryException) {
1557 * if (#resource != null) //nullcheck skipped if Expression is provably non-null
1558 * try {
1559 * #resource.close();
1560 * } catch (Throwable #suppressedException) {
1561 * #primaryException.addSuppressed(#suppressedException);
1562 * }
1563 * throw #primaryException;
1564 * }
1565 * }
1566 *
1567 * @param tree The try statement to inspect.
1568 * @return a desugared try-with-resources tree, or the original
1569 * try block if there are no resources to manage.
1570 */
1571 JCTree makeTwrTry(JCTry tree) {
1572 make_at(tree.pos());
1573 twrVars = twrVars.dup();
1574 JCBlock twrBlock = makeTwrBlock(tree.resources, tree.body, 0);
1575 if (tree.catchers.isEmpty() && tree.finalizer == null)
1576 result = translate(twrBlock);
1577 else
1578 result = translate(make.Try(twrBlock, tree.catchers, tree.finalizer));
1579 twrVars = twrVars.leave();
1580 return result;
1581 }
1582
1583 private JCBlock makeTwrBlock(List<JCTree> resources, JCBlock block, int depth) {
1584 if (resources.isEmpty())
1585 return block;
1586
1587 // Add resource declaration or expression to block statements
1588 ListBuffer<JCStatement> stats = new ListBuffer<>();
1589 JCTree resource = resources.head;
1590 JCExpression resourceUse;
1591 boolean resourceNonNull;
1592 if (resource instanceof JCVariableDecl variableDecl) {
1593 resourceUse = make.Ident(variableDecl.sym).setType(resource.type);
1594 resourceNonNull = variableDecl.init != null && TreeInfo.skipParens(variableDecl.init).hasTag(NEWCLASS);
1595 stats.add(variableDecl);
1596 } else {
1597 Assert.check(resource instanceof JCExpression);
1598 VarSymbol syntheticTwrVar =
1599 new VarSymbol(SYNTHETIC | FINAL,
1600 makeSyntheticName(names.fromString("twrVar" +
1601 depth), twrVars),
1602 (resource.type.hasTag(BOT)) ?
1603 syms.autoCloseableType : resource.type,
1604 currentMethodSym);
1605 twrVars.enter(syntheticTwrVar);
1606 JCVariableDecl syntheticTwrVarDecl =
1607 make.VarDef(syntheticTwrVar, (JCExpression)resource);
1608 resourceUse = (JCExpression)make.Ident(syntheticTwrVar);
1609 resourceNonNull = false;
1610 stats.add(syntheticTwrVarDecl);
1611 }
1612
1613 //create (semi-) finally block that will be copied into the main try body:
1614 int oldPos = make.pos;
1615 make.at(TreeInfo.endPos(block));
1616
1617 // if (#resource != null) { #resource.close(); }
1618 JCStatement bodyCloseStatement = makeResourceCloseInvocation(resourceUse);
1619
1620 if (!resourceNonNull) {
1621 bodyCloseStatement = make.If(makeNonNullCheck(resourceUse),
1622 bodyCloseStatement,
1623 null);
1624 }
1625
1626 JCBlock finallyClause = make.Block(BODY_ONLY_FINALIZE, List.of(bodyCloseStatement));
1627 make.at(oldPos);
1628
1629 // Create catch clause that saves exception, closes the resource and then rethrows the exception:
1630 VarSymbol primaryException =
1631 new VarSymbol(FINAL|SYNTHETIC,
1632 names.fromString("t" +
1633 target.syntheticNameChar()),
1634 syms.throwableType,
1635 currentMethodSym);
1636 JCVariableDecl primaryExceptionDecl = make.VarDef(primaryException, null);
1637
1638 // close resource:
1639 // try {
1640 // #resource.close();
1641 // } catch (Throwable #suppressedException) {
1642 // #primaryException.addSuppressed(#suppressedException);
1643 // }
1644 VarSymbol suppressedException =
1645 new VarSymbol(SYNTHETIC, make.paramName(2),
1646 syms.throwableType,
1647 currentMethodSym);
1648 JCStatement addSuppressedStatement =
1649 make.Exec(makeCall(make.Ident(primaryException),
1650 names.addSuppressed,
1651 List.of(make.Ident(suppressedException))));
1652 JCBlock closeResourceTryBlock =
1653 make.Block(0L, List.of(makeResourceCloseInvocation(resourceUse)));
1654 JCVariableDecl catchSuppressedDecl = make.VarDef(suppressedException, null);
1655 JCBlock catchSuppressedBlock = make.Block(0L, List.of(addSuppressedStatement));
1656 List<JCCatch> catchSuppressedClauses =
1657 List.of(make.Catch(catchSuppressedDecl, catchSuppressedBlock));
1658 JCTry closeResourceTry = make.Try(closeResourceTryBlock, catchSuppressedClauses, null);
1659 closeResourceTry.finallyCanCompleteNormally = true;
1660
1661 JCStatement exceptionalCloseStatement = closeResourceTry;
1662
1663 if (!resourceNonNull) {
1664 // if (#resource != null) { }
1665 exceptionalCloseStatement = make.If(makeNonNullCheck(resourceUse),
1666 exceptionalCloseStatement,
1667 null);
1668 }
1669
1670 JCStatement exceptionalRethrow = make.Throw(make.Ident(primaryException));
1671 JCBlock exceptionalCloseBlock = make.Block(0L, List.of(exceptionalCloseStatement, exceptionalRethrow));
1672 JCCatch exceptionalCatchClause = make.Catch(primaryExceptionDecl, exceptionalCloseBlock);
1673
1674 //create the main try statement with the close:
1675 JCTry outerTry = make.Try(makeTwrBlock(resources.tail, block, depth + 1),
1676 List.of(exceptionalCatchClause),
1677 finallyClause);
1678
1679 outerTry.finallyCanCompleteNormally = true;
1680 stats.add(outerTry);
1681
1682 JCBlock newBlock = make.Block(0L, stats.toList());
1683 return newBlock;
1684 }
1685
1686 private JCStatement makeResourceCloseInvocation(JCExpression resource) {
1687 // convert to AutoCloseable if needed
1688 if (types.asSuper(resource.type, syms.autoCloseableType.tsym) == null) {
1689 resource = convert(resource, syms.autoCloseableType);
1690 }
1691
1692 // create resource.close() method invocation
1693 JCExpression resourceClose = makeCall(resource,
1694 names.close,
1695 List.nil());
1696 return make.Exec(resourceClose);
1697 }
1698
1699 private JCExpression makeNonNullCheck(JCExpression expression) {
1700 return makeBinary(NE, expression, makeNull());
1701 }
1702
1703 /** Construct a tree that represents the outer instance
1704 * {@code C.this}. Never pick the current `this'.
1705 * @param pos The source code position to be used for the tree.
1706 * @param c The qualifier class.
1707 */
1708 JCExpression makeOuterThis(DiagnosticPosition pos, TypeSymbol c) {
1709 List<VarSymbol> ots = outerThisStack;
1710 if (ots.isEmpty()) {
1711 log.error(pos, Errors.NoEnclInstanceOfTypeInScope(c));
1712 return makeNull();
1713 }
1714 VarSymbol ot = ots.head;
1715 JCExpression tree = access(make.at(pos).Ident(ot));
1716 ot.flags_field &= ~NOOUTERTHIS;
1717 TypeSymbol otc = ot.type.tsym;
1718 while (otc != c) {
1719 do {
1720 ots = ots.tail;
1721 if (ots.isEmpty()) {
1722 log.error(pos, Errors.NoEnclInstanceOfTypeInScope(c));
1723 Assert.error(); // should have been caught in Attr
1724 return tree;
1725 }
1726 ot = ots.head;
1727 } while (ot.owner != otc);
1728 if (otc.owner.kind != PCK && !otc.hasOuterInstance()) {
1729 log.error(pos, Errors.NoEnclInstanceOfTypeInScope(c));
1730 Assert.error(); // should have been caught in Attr
1731 return makeNull();
1732 }
1733 tree = access(make.at(pos).Select(tree, ot));
1734 ot.flags_field &= ~NOOUTERTHIS;
1735 otc = ot.type.tsym;
1736 }
1737 return tree;
1738 }
1739
1740 /** Construct a tree that represents the closest outer instance
1741 * {@code C.this} such that the given symbol is a member of C.
1742 * @param pos The source code position to be used for the tree.
1743 * @param sym The accessed symbol.
1744 * @param preciseMatch should we accept a type that is a subtype of
1745 * sym's owner, even if it doesn't contain sym
1746 * due to hiding, overriding, or non-inheritance
1747 * due to protection?
1748 */
1749 JCExpression makeOwnerThis(DiagnosticPosition pos, Symbol sym, boolean preciseMatch) {
1750 if (preciseMatch ? sym.isMemberOf(currentClass, types)
1751 : currentClass.isSubClass(sym.owner, types)) {
1752 // in this case, `this' works fine
1753 return make.at(pos).This(currentClass.erasure(types));
1754 } else {
1755 // need to go via this$n
1756 return makeOwnerThisN(pos, sym, preciseMatch);
1757 }
1758 }
1759
1760 /**
1761 * Similar to makeOwnerThis but will never pick "this".
1762 */
1763 JCExpression makeOwnerThisN(DiagnosticPosition pos, Symbol sym, boolean preciseMatch) {
1764 Symbol c = sym.owner;
1765 List<VarSymbol> ots = outerThisStack;
1766 if (ots.isEmpty()) {
1767 log.error(pos, Errors.NoEnclInstanceOfTypeInScope(c));
1768 return makeNull();
1769 }
1770 VarSymbol ot = ots.head;
1771 JCExpression tree = access(make.at(pos).Ident(ot));
1772 ot.flags_field &= ~NOOUTERTHIS;
1773 TypeSymbol otc = ot.type.tsym;
1774 while (!(preciseMatch ? sym.isMemberOf(otc, types) : otc.isSubClass(sym.owner, types))) {
1775 do {
1776 ots = ots.tail;
1777 if (ots.isEmpty()) {
1778 log.error(pos, Errors.NoEnclInstanceOfTypeInScope(c));
1779 return tree;
1780 }
1781 ot = ots.head;
1782 } while (ot.owner != otc);
1783 tree = access(make.at(pos).Select(tree, ot));
1784 ot.flags_field &= ~NOOUTERTHIS;
1785 otc = ot.type.tsym;
1786 }
1787 return tree;
1788 }
1789
1790 /** Return tree simulating the assignment {@code this.name = name}, where
1791 * name is the name of a free variable.
1792 */
1793 JCStatement initField(int pos, Symbol rhs, Symbol lhs) {
1794 Assert.check(rhs.owner.kind == MTH);
1795 Assert.check(rhs.owner.owner == lhs.owner);
1796 make.at(pos);
1797 return
1798 make.Exec(
1799 make.Assign(
1800 make.Select(make.This(lhs.owner.erasure(types)), lhs),
1801 make.Ident(rhs)).setType(lhs.erasure(types)));
1802 }
1803
1804 /**
1805 * Return tree simulating null checking outer this and/or assigning. This is
1806 * called when a null check is required (nullCheckOuterThis), or a synthetic
1807 * field is generated (stores).
1808 */
1809 JCStatement initOuterThis(int pos, VarSymbol rhs, boolean stores) {
1810 Assert.check(rhs.owner.kind == MTH);
1811 Assert.check(nullCheckOuterThis || stores); // One of the flags must be true
1812 make.at(pos);
1813 JCExpression expression = make.Ident(rhs);
1814 if (nullCheckOuterThis) {
1815 expression = attr.makeNullCheck(expression);
1816 }
1817 if (stores) {
1818 VarSymbol lhs = outerThisStack.head;
1819 Assert.check(rhs.owner.owner == lhs.owner);
1820 expression = make.Assign(
1821 make.Select(make.This(lhs.owner.erasure(types)), lhs),
1822 expression).setType(lhs.erasure(types));
1823 }
1824 return make.Exec(expression);
1825 }
1826
1827 /* ************************************************************************
1828 * Code for .class
1829 *************************************************************************/
1830
1831 /** Return the symbol of a class to contain a cache of
1832 * compiler-generated statics such as class$ and the
1833 * $assertionsDisabled flag. We create an anonymous nested class
1834 * (unless one already exists) and return its symbol. However,
1835 * for backward compatibility in 1.4 and earlier we use the
1836 * top-level class itself.
1837 */
1838 private ClassSymbol outerCacheClass() {
1839 ClassSymbol clazz = outermostClassDef.sym;
1840 Scope s = clazz.members();
1841 for (Symbol sym : s.getSymbols(NON_RECURSIVE))
1842 if (sym.kind == TYP &&
1843 sym.name == names.empty &&
1844 (sym.flags() & INTERFACE) == 0) return (ClassSymbol) sym;
1845 // IDENTITY_TYPE will be interpreted as ACC_SUPER for older class files so we are fine
1846 return makeEmptyClass(STATIC | SYNTHETIC | IDENTITY_TYPE, clazz).sym;
1847 }
1848
1849 /** Create an attributed tree of the form left.name(). */
1850 private JCMethodInvocation makeCall(JCExpression left, Name name, List<JCExpression> args) {
1851 Assert.checkNonNull(left.type);
1852 Symbol funcsym = lookupMethod(make_pos, name, left.type,
1853 TreeInfo.types(args));
1854 return make.App(make.Select(left, funcsym), args);
1855 }
1856
1857 /** The tree simulating a T.class expression.
1858 * @param clazz The tree identifying type T.
1859 */
1860 private JCExpression classOf(JCTree clazz) {
1861 return classOfType(clazz.type, clazz.pos());
1862 }
1863
1864 private JCExpression classOfType(Type type, DiagnosticPosition pos) {
1865 switch (type.getTag()) {
1866 case BYTE: case SHORT: case CHAR: case INT: case LONG: case FLOAT:
1867 case DOUBLE: case BOOLEAN: case VOID:
1868 // replace with <BoxedClass>.TYPE
1869 ClassSymbol c = types.boxedClass(type);
1870 Symbol typeSym =
1871 rs.accessBase(
1872 rs.findIdentInType(pos, attrEnv, c.type, names.TYPE, KindSelector.VAR),
1873 pos, c.type, names.TYPE, true);
1874 if (typeSym.kind == VAR)
1875 ((VarSymbol)typeSym).getConstValue(); // ensure initializer is evaluated
1876 return make.QualIdent(typeSym);
1877 case CLASS: case ARRAY:
1878 VarSymbol sym = new VarSymbol(
1879 STATIC | PUBLIC | FINAL, names._class,
1880 syms.classType, type.tsym);
1881 return make_at(pos).Select(make.Type(type), sym);
1882 default:
1883 throw new AssertionError();
1884 }
1885 }
1886
1887 /* ************************************************************************
1888 * Code for enabling/disabling assertions.
1889 *************************************************************************/
1890
1891 private ClassSymbol assertionsDisabledClassCache;
1892
1893 /**Used to create an auxiliary class to hold $assertionsDisabled for interfaces.
1894 */
1895 private ClassSymbol assertionsDisabledClass() {
1896 if (assertionsDisabledClassCache != null) return assertionsDisabledClassCache;
1897
1898 // IDENTITY_TYPE will be interpreted as ACC_SUPER for older class files so we are fine
1899 assertionsDisabledClassCache = makeEmptyClass(STATIC | SYNTHETIC | IDENTITY_TYPE, outermostClassDef.sym).sym;
1900
1901 return assertionsDisabledClassCache;
1902 }
1903
1904 // This code is not particularly robust if the user has
1905 // previously declared a member named '$assertionsDisabled'.
1906 // The same faulty idiom also appears in the translation of
1907 // class literals above. We should report an error if a
1908 // previous declaration is not synthetic.
1909
1910 private JCExpression assertFlagTest(DiagnosticPosition pos) {
1911 // Outermost class may be either true class or an interface.
1912 ClassSymbol outermostClass = outermostClassDef.sym;
1913
1914 //only classes can hold a non-public field, look for a usable one:
1915 ClassSymbol container = !currentClass.isInterface() ? currentClass :
1916 assertionsDisabledClass();
1917
1918 VarSymbol assertDisabledSym =
1919 (VarSymbol)lookupSynthetic(dollarAssertionsDisabled,
1920 container.members());
1921 if (assertDisabledSym == null) {
1922 assertDisabledSym =
1923 new VarSymbol(STATIC | FINAL | SYNTHETIC,
1924 dollarAssertionsDisabled,
1925 syms.booleanType,
1926 container);
1927 enterSynthetic(pos, assertDisabledSym, container.members());
1928 Symbol desiredAssertionStatusSym = lookupMethod(pos,
1929 names.desiredAssertionStatus,
1930 types.erasure(syms.classType),
1931 List.nil());
1932 JCClassDecl containerDef = classDef(container);
1933 make_at(containerDef.pos());
1934 JCExpression notStatus = makeUnary(NOT, make.App(make.Select(
1935 classOfType(types.erasure(outermostClass.type),
1936 containerDef.pos()),
1937 desiredAssertionStatusSym)));
1938 JCVariableDecl assertDisabledDef = make.VarDef(assertDisabledSym,
1939 notStatus);
1940 containerDef.defs = containerDef.defs.prepend(assertDisabledDef);
1941
1942 if (currentClass.isInterface()) {
1943 //need to load the assertions enabled/disabled state while
1944 //initializing the interface:
1945 JCClassDecl currentClassDef = classDef(currentClass);
1946 make_at(currentClassDef.pos());
1947 JCStatement dummy = make.If(make.QualIdent(assertDisabledSym), make.Skip(), null);
1948 JCBlock clinit = make.Block(STATIC, List.of(dummy));
1949 currentClassDef.defs = currentClassDef.defs.prepend(clinit);
1950 }
1951 }
1952 make_at(pos);
1953 return makeUnary(NOT, make.Ident(assertDisabledSym));
1954 }
1955
1956
1957 /* ************************************************************************
1958 * Building blocks for let expressions
1959 *************************************************************************/
1960
1961 interface TreeBuilder {
1962 JCExpression build(JCExpression arg);
1963 }
1964
1965 /** Construct an expression using the builder, with the given rval
1966 * expression as an argument to the builder. However, the rval
1967 * expression must be computed only once, even if used multiple
1968 * times in the result of the builder. We do that by
1969 * constructing a "let" expression that saves the rvalue into a
1970 * temporary variable and then uses the temporary variable in
1971 * place of the expression built by the builder. The complete
1972 * resulting expression is of the form
1973 * <pre>
1974 * (let <b>TYPE</b> <b>TEMP</b> = <b>RVAL</b>;
1975 * in (<b>BUILDER</b>(<b>TEMP</b>)))
1976 * </pre>
1977 * where <code><b>TEMP</b></code> is a newly declared variable
1978 * in the let expression.
1979 */
1980 JCExpression abstractRval(JCExpression rval, Type type, TreeBuilder builder) {
1981 rval = TreeInfo.skipParens(rval);
1982 switch (rval.getTag()) {
1983 case LITERAL:
1984 return builder.build(rval);
1985 case IDENT:
1986 JCIdent id = (JCIdent) rval;
1987 if ((id.sym.flags() & FINAL) != 0 && id.sym.owner.kind == MTH)
1988 return builder.build(rval);
1989 }
1990 Name name = TreeInfo.name(rval);
1991 if (name == names._super || name == names._this)
1992 return builder.build(rval);
1993 VarSymbol var =
1994 new VarSymbol(FINAL|SYNTHETIC,
1995 names.fromString(
1996 target.syntheticNameChar()
1997 + "" + rval.hashCode()),
1998 type,
1999 currentMethodSym);
2000 rval = convert(rval,type);
2001 JCVariableDecl def = make.VarDef(var, rval); // XXX cast
2002 JCExpression built = builder.build(make.Ident(var));
2003 JCExpression res = make.LetExpr(def, built);
2004 res.type = built.type;
2005 return res;
2006 }
2007
2008 // same as above, with the type of the temporary variable computed
2009 JCExpression abstractRval(JCExpression rval, TreeBuilder builder) {
2010 return abstractRval(rval, rval.type, builder);
2011 }
2012
2013 // same as above, but for an expression that may be used as either
2014 // an rvalue or an lvalue. This requires special handling for
2015 // Select expressions, where we place the left-hand-side of the
2016 // select in a temporary, and for Indexed expressions, where we
2017 // place both the indexed expression and the index value in temps.
2018 JCExpression abstractLval(JCExpression lval, final TreeBuilder builder) {
2019 lval = TreeInfo.skipParens(lval);
2020 switch (lval.getTag()) {
2021 case IDENT:
2022 return builder.build(lval);
2023 case SELECT: {
2024 final JCFieldAccess s = (JCFieldAccess)lval;
2025 Symbol lid = TreeInfo.symbol(s.selected);
2026 if (lid != null && lid.kind == TYP) return builder.build(lval);
2027 return abstractRval(s.selected, selected -> builder.build(make.Select(selected, s.sym)));
2028 }
2029 case INDEXED: {
2030 final JCArrayAccess i = (JCArrayAccess)lval;
2031 return abstractRval(i.indexed, indexed -> abstractRval(i.index, syms.intType, index -> {
2032 JCExpression newLval = make.Indexed(indexed, index);
2033 newLval.setType(i.type);
2034 return builder.build(newLval);
2035 }));
2036 }
2037 case TYPECAST: {
2038 return abstractLval(((JCTypeCast)lval).expr, builder);
2039 }
2040 }
2041 throw new AssertionError(lval);
2042 }
2043
2044 // evaluate and discard the first expression, then evaluate the second.
2045 JCExpression makeComma(final JCExpression expr1, final JCExpression expr2) {
2046 JCExpression res = make.LetExpr(List.of(make.Exec(expr1)), expr2);
2047 res.type = expr2.type;
2048 return res;
2049 }
2050
2051 /* ************************************************************************
2052 * Translation methods
2053 *************************************************************************/
2054
2055 /** Visitor argument: enclosing operator node.
2056 */
2057 private JCExpression enclOp;
2058
2059 /** Visitor method: Translate a single node.
2060 * Attach the source position from the old tree to its replacement tree.
2061 */
2062 @Override
2063 public <T extends JCTree> T translate(T tree) {
2064 if (tree == null) {
2065 return null;
2066 } else {
2067 make_at(tree.pos());
2068 T result = super.translate(tree);
2069 if (result != null && result != tree) {
2070 result.endpos = tree.endpos;
2071 }
2072 return result;
2073 }
2074 }
2075
2076 /** Visitor method: Translate a single node, boxing or unboxing if needed.
2077 */
2078 public <T extends JCExpression> T translate(T tree, Type type) {
2079 return (tree == null) ? null : boxIfNeeded(translate(tree), type);
2080 }
2081
2082 /** Visitor method: Translate tree.
2083 */
2084 public <T extends JCTree> T translate(T tree, JCExpression enclOp) {
2085 JCExpression prevEnclOp = this.enclOp;
2086 this.enclOp = enclOp;
2087 T res = translate(tree);
2088 this.enclOp = prevEnclOp;
2089 return res;
2090 }
2091
2092 /** Visitor method: Translate list of trees.
2093 */
2094 public <T extends JCExpression> List<T> translate(List<T> trees, Type type) {
2095 if (trees == null) return null;
2096 for (List<T> l = trees; l.nonEmpty(); l = l.tail)
2097 l.head = translate(l.head, type);
2098 return trees;
2099 }
2100
2101 public void visitPackageDef(JCPackageDecl tree) {
2102 if (!needPackageInfoClass(tree))
2103 return;
2104
2105 long flags = Flags.ABSTRACT | Flags.INTERFACE;
2106 // package-info is marked SYNTHETIC in JDK 1.6 and later releases
2107 flags = flags | Flags.SYNTHETIC;
2108 ClassSymbol c = tree.packge.package_info;
2109 c.setAttributes(tree.packge);
2110 c.flags_field |= flags;
2111 ClassType ctype = (ClassType) c.type;
2112 ctype.supertype_field = syms.objectType;
2113 ctype.interfaces_field = List.nil();
2114 createInfoClass(tree.annotations, c);
2115 }
2116 // where
2117 private boolean needPackageInfoClass(JCPackageDecl pd) {
2118 switch (pkginfoOpt) {
2119 case ALWAYS:
2120 return true;
2121 case LEGACY:
2122 return pd.getAnnotations().nonEmpty();
2123 case NONEMPTY:
2124 for (Attribute.Compound a :
2125 pd.packge.getDeclarationAttributes()) {
2126 Attribute.RetentionPolicy p = types.getRetention(a);
2127 if (p != Attribute.RetentionPolicy.SOURCE)
2128 return true;
2129 }
2130 return false;
2131 }
2132 throw new AssertionError();
2133 }
2134
2135 public void visitModuleDef(JCModuleDecl tree) {
2136 ModuleSymbol msym = tree.sym;
2137 ClassSymbol c = msym.module_info;
2138 c.setAttributes(msym);
2139 c.flags_field |= Flags.MODULE;
2140 createInfoClass(List.nil(), tree.sym.module_info);
2141 }
2142
2143 private void createInfoClass(List<JCAnnotation> annots, ClassSymbol c) {
2144 long flags = Flags.ABSTRACT | Flags.INTERFACE;
2145 JCClassDecl infoClass =
2146 make.ClassDef(make.Modifiers(flags, annots),
2147 c.name, List.nil(),
2148 null, List.nil(), List.nil());
2149 infoClass.sym = c;
2150 translated.append(infoClass);
2151 }
2152
2153 public void visitClassDef(JCClassDecl tree) {
2154 Env<AttrContext> prevEnv = attrEnv;
2155 ClassSymbol currentClassPrev = currentClass;
2156 MethodSymbol currentMethodSymPrev = currentMethodSym;
2157
2158 currentClass = tree.sym;
2159 currentMethodSym = null;
2160 attrEnv = typeEnvs.remove(currentClass);
2161 if (attrEnv == null)
2162 attrEnv = prevEnv;
2163
2164 classdefs.put(currentClass, tree);
2165
2166 Map<Symbol, Symbol> prevProxies = proxies;
2167 proxies = new HashMap<>(proxies);
2168 List<VarSymbol> prevOuterThisStack = outerThisStack;
2169
2170 // If this is an enum definition
2171 if ((tree.mods.flags & ENUM) != 0 &&
2172 (types.supertype(currentClass.type).tsym.flags() & ENUM) == 0)
2173 visitEnumDef(tree);
2174
2175 if ((tree.mods.flags & RECORD) != 0) {
2176 visitRecordDef(tree);
2177 }
2178
2179 // If this is a nested class, define a this$n field for
2180 // it and add to proxies.
2181 JCVariableDecl otdef = null;
2182 if (currentClass.hasOuterInstance())
2183 otdef = outerThisDef(tree.pos, currentClass);
2184
2185 // If this is a local class, define proxies for all its free variables.
2186 List<JCVariableDecl> fvdefs = freevarDefs(
2187 tree.pos, freevars(currentClass), currentClass, allowValueClasses && currentClass.isValueClass() ? STRICT : LOCAL_CAPTURE_FIELD);
2188
2189 // Recursively translate superclass, interfaces.
2190 tree.extending = translate(tree.extending);
2191 tree.implementing = translate(tree.implementing);
2192
2193 if (currentClass.isDirectlyOrIndirectlyLocal()) {
2194 ClassSymbol encl = currentClass.owner.enclClass();
2195 if (encl.trans_local == null) {
2196 encl.trans_local = List.nil();
2197 }
2198 encl.trans_local = encl.trans_local.prepend(currentClass);
2199 }
2200
2201 // Recursively translate members, taking into account that new members
2202 // might be created during the translation and prepended to the member
2203 // list `tree.defs'.
2204 List<JCTree> seen = List.nil();
2205 while (tree.defs != seen) {
2206 List<JCTree> unseen = tree.defs;
2207 for (List<JCTree> l = unseen; l.nonEmpty() && l != seen; l = l.tail) {
2208 JCTree outermostMemberDefPrev = outermostMemberDef;
2209 if (outermostMemberDefPrev == null) outermostMemberDef = l.head;
2210 l.head = translate(l.head);
2211 outermostMemberDef = outermostMemberDefPrev;
2212 }
2213 seen = unseen;
2214 }
2215
2216 // Convert a protected modifier to public, mask static modifier.
2217 if ((tree.mods.flags & PROTECTED) != 0) tree.mods.flags |= PUBLIC;
2218 tree.mods.flags &= ClassFlags;
2219
2220 // Convert name to flat representation, replacing '.' by '$'.
2221 tree.name = Convert.shortName(currentClass.flatName());
2222
2223 // Add free variables proxy definitions to class.
2224
2225 for (List<JCVariableDecl> l = fvdefs; l.nonEmpty(); l = l.tail) {
2226 tree.defs = tree.defs.prepend(l.head);
2227 enterSynthetic(tree.pos(), l.head.sym, currentClass.members());
2228 }
2229 // If this$n was accessed, add the field definition and prepend
2230 // initializer code to any super() invocation to initialize it
2231 // otherwise prepend enclosing instance null check code if required
2232 emitOuter:
2233 if (currentClass.hasOuterInstance()) {
2234 boolean storesThis = shouldEmitOuterThis(currentClass);
2235 if (storesThis) {
2236 tree.defs = tree.defs.prepend(otdef);
2237 enterSynthetic(tree.pos(), otdef.sym, currentClass.members());
2238 } else if (!nullCheckOuterThis) {
2239 break emitOuter;
2240 }
2241
2242 for (JCTree def : tree.defs) {
2243 if (TreeInfo.isConstructor(def)) {
2244 JCMethodDecl mdef = (JCMethodDecl)def;
2245 if (TreeInfo.hasConstructorCall(mdef, names._super)) {
2246 List<JCStatement> initializer = List.of(initOuterThis(mdef.body.pos, mdef.params.head.sym, storesThis)) ;
2247 TreeInfo.mapSuperCalls(mdef.body, supercall -> make.Block(0, initializer.append(supercall)));
2248 }
2249 }
2250 }
2251 }
2252
2253 proxies = prevProxies;
2254 outerThisStack = prevOuterThisStack;
2255
2256 // Append translated tree to `translated' queue.
2257 translated.append(tree);
2258
2259 attrEnv = prevEnv;
2260 currentClass = currentClassPrev;
2261 currentMethodSym = currentMethodSymPrev;
2262
2263 // Return empty block {} as a placeholder for an inner class.
2264 result = make_at(tree.pos()).Block(SYNTHETIC, List.nil());
2265 }
2266
2267 private boolean shouldEmitOuterThis(ClassSymbol sym) {
2268 if (!optimizeOuterThis) {
2269 // Optimization is disabled
2270 return true;
2271 }
2272 if ((outerThisStack.head.flags_field & NOOUTERTHIS) == 0) {
2273 // Enclosing instance field is used
2274 return true;
2275 }
2276 if (rs.isSerializable(sym.type)) {
2277 // Class is serializable
2278 return true;
2279 }
2280 return false;
2281 }
2282
2283 List<JCTree> generateMandatedAccessors(JCClassDecl tree) {
2284 List<JCVariableDecl> fields = TreeInfo.recordFields(tree);
2285 return tree.sym.getRecordComponents().stream()
2286 .filter(rc -> (rc.accessor.flags() & Flags.GENERATED_MEMBER) != 0)
2287 .map(rc -> {
2288 // we need to return the field not the record component
2289 JCVariableDecl field = fields.stream().filter(f -> f.name == rc.name).findAny().get();
2290 make_at(tree.pos());
2291 return make.MethodDef(rc.accessor, make.Block(0,
2292 List.of(make.Return(make.Ident(field)))));
2293 }).collect(List.collector());
2294 }
2295
2296 /** Translate an enum class. */
2297 private void visitEnumDef(JCClassDecl tree) {
2298 make_at(tree.pos());
2299
2300 // add the supertype, if needed
2301 if (tree.extending == null)
2302 tree.extending = make.Type(types.supertype(tree.type));
2303
2304 // classOfType adds a cache field to tree.defs
2305 JCExpression e_class = classOfType(tree.sym.type, tree.pos()).
2306 setType(types.erasure(syms.classType));
2307
2308 // process each enumeration constant, adding implicit constructor parameters
2309 int nextOrdinal = 0;
2310 ListBuffer<JCExpression> values = new ListBuffer<>();
2311 ListBuffer<JCTree> enumDefs = new ListBuffer<>();
2312 ListBuffer<JCTree> otherDefs = new ListBuffer<>();
2313 for (List<JCTree> defs = tree.defs;
2314 defs.nonEmpty();
2315 defs=defs.tail) {
2316 if (defs.head.hasTag(VARDEF) && (((JCVariableDecl) defs.head).mods.flags & ENUM) != 0) {
2317 JCVariableDecl var = (JCVariableDecl)defs.head;
2318 visitEnumConstantDef(var, nextOrdinal++);
2319 values.append(make.QualIdent(var.sym));
2320 enumDefs.append(var);
2321 } else {
2322 otherDefs.append(defs.head);
2323 }
2324 }
2325
2326 // synthetic private static T[] $values() { return new T[] { a, b, c }; }
2327 // synthetic private static final T[] $VALUES = $values();
2328 Name valuesName = syntheticName(tree, "VALUES");
2329 Type arrayType = new ArrayType(types.erasure(tree.type), syms.arrayClass);
2330 VarSymbol valuesVar = new VarSymbol(PRIVATE|FINAL|STATIC|SYNTHETIC,
2331 valuesName,
2332 arrayType,
2333 tree.type.tsym);
2334 JCNewArray newArray = make.NewArray(make.Type(types.erasure(tree.type)),
2335 List.nil(),
2336 values.toList());
2337 newArray.type = arrayType;
2338
2339 MethodSymbol valuesMethod = new MethodSymbol(PRIVATE|STATIC|SYNTHETIC,
2340 syntheticName(tree, "values"),
2341 new MethodType(List.nil(), arrayType, List.nil(), tree.type.tsym),
2342 tree.type.tsym);
2343 enumDefs.append(make.MethodDef(valuesMethod, make.Block(0, List.of(make.Return(newArray)))));
2344 tree.sym.members().enter(valuesMethod);
2345
2346 enumDefs.append(make.VarDef(valuesVar, make.App(make.QualIdent(valuesMethod))));
2347 tree.sym.members().enter(valuesVar);
2348
2349 MethodSymbol valuesSym = lookupMethod(tree.pos(), names.values,
2350 tree.type, List.nil());
2351 List<JCStatement> valuesBody;
2352 if (useClone()) {
2353 // return (T[]) $VALUES.clone();
2354 JCTypeCast valuesResult =
2355 make.TypeCast(valuesSym.type.getReturnType(),
2356 make.App(make.Select(make.Ident(valuesVar),
2357 syms.arrayCloneMethod)));
2358 valuesBody = List.of(make.Return(valuesResult));
2359 } else {
2360 // template: T[] $result = new T[$values.length];
2361 Name resultName = syntheticName(tree, "result");
2362 VarSymbol resultVar = new VarSymbol(FINAL|SYNTHETIC,
2363 resultName,
2364 arrayType,
2365 valuesSym);
2366 JCNewArray resultArray = make.NewArray(make.Type(types.erasure(tree.type)),
2367 List.of(make.Select(make.Ident(valuesVar), syms.lengthVar)),
2368 null);
2369 resultArray.type = arrayType;
2370 JCVariableDecl decl = make.VarDef(resultVar, resultArray);
2371
2372 // template: System.arraycopy($VALUES, 0, $result, 0, $VALUES.length);
2373 if (systemArraycopyMethod == null) {
2374 systemArraycopyMethod =
2375 new MethodSymbol(PUBLIC | STATIC,
2376 names.fromString("arraycopy"),
2377 new MethodType(List.of(syms.objectType,
2378 syms.intType,
2379 syms.objectType,
2380 syms.intType,
2381 syms.intType),
2382 syms.voidType,
2383 List.nil(),
2384 syms.methodClass),
2385 syms.systemType.tsym);
2386 }
2387 JCStatement copy =
2388 make.Exec(make.App(make.Select(make.Ident(syms.systemType.tsym),
2389 systemArraycopyMethod),
2390 List.of(make.Ident(valuesVar), make.Literal(0),
2391 make.Ident(resultVar), make.Literal(0),
2392 make.Select(make.Ident(valuesVar), syms.lengthVar))));
2393
2394 // template: return $result;
2395 JCStatement ret = make.Return(make.Ident(resultVar));
2396 valuesBody = List.of(decl, copy, ret);
2397 }
2398
2399 JCMethodDecl valuesDef =
2400 make.MethodDef(valuesSym, make.Block(0, valuesBody));
2401
2402 enumDefs.append(valuesDef);
2403
2404 if (debugLower)
2405 System.err.println(tree.sym + ".valuesDef = " + valuesDef);
2406
2407 /** The template for the following code is:
2408 *
2409 * public static E valueOf(String name) {
2410 * return (E)Enum.valueOf(E.class, name);
2411 * }
2412 *
2413 * where E is tree.sym
2414 */
2415 MethodSymbol valueOfSym = lookupMethod(tree.pos(),
2416 names.valueOf,
2417 tree.sym.type,
2418 List.of(syms.stringType));
2419 Assert.check((valueOfSym.flags() & STATIC) != 0);
2420 VarSymbol nameArgSym = valueOfSym.params.head;
2421 JCIdent nameVal = make.Ident(nameArgSym);
2422 JCStatement enum_ValueOf =
2423 make.Return(make.TypeCast(tree.sym.type,
2424 makeCall(make.Ident(syms.enumSym),
2425 names.valueOf,
2426 List.of(e_class, nameVal))));
2427 JCMethodDecl valueOf = make.MethodDef(valueOfSym,
2428 make.Block(0, List.of(enum_ValueOf)));
2429 nameVal.sym = valueOf.params.head.sym;
2430 if (debugLower)
2431 System.err.println(tree.sym + ".valueOf = " + valueOf);
2432 enumDefs.append(valueOf);
2433
2434 enumDefs.appendList(otherDefs.toList());
2435 tree.defs = enumDefs.toList();
2436 }
2437 // where
2438 private MethodSymbol systemArraycopyMethod;
2439 private boolean useClone() {
2440 try {
2441 return syms.objectType.tsym.members().findFirst(names.clone) != null;
2442 }
2443 catch (CompletionFailure e) {
2444 return false;
2445 }
2446 }
2447
2448 private Name syntheticName(JCClassDecl tree, String baseName) {
2449 Name valuesName = names.fromString(target.syntheticNameChar() + baseName);
2450 while (tree.sym.members().findFirst(valuesName) != null) // avoid name clash
2451 valuesName = names.fromString(valuesName + "" + target.syntheticNameChar());
2452 return valuesName;
2453 }
2454
2455 /** Translate an enumeration constant and its initializer. */
2456 private void visitEnumConstantDef(JCVariableDecl var, int ordinal) {
2457 JCNewClass varDef = (JCNewClass)var.init;
2458 varDef.args = varDef.args.
2459 prepend(makeLit(syms.intType, ordinal)).
2460 prepend(makeLit(syms.stringType, var.name.toString()));
2461 }
2462
2463 private List<VarSymbol> recordVars(Type t) {
2464 List<VarSymbol> vars = List.nil();
2465 while (!t.hasTag(NONE)) {
2466 if (t.hasTag(CLASS)) {
2467 for (Symbol s : t.tsym.members().getSymbols(s -> s.kind == VAR && (s.flags() & RECORD) != 0)) {
2468 vars = vars.prepend((VarSymbol)s);
2469 }
2470 }
2471 t = types.supertype(t);
2472 }
2473 return vars;
2474 }
2475
2476 /** Translate a record. */
2477 private void visitRecordDef(JCClassDecl tree) {
2478 make_at(tree.pos());
2479 List<VarSymbol> vars = recordVars(tree.type);
2480 MethodHandleSymbol[] getterMethHandles = new MethodHandleSymbol[vars.size()];
2481 int index = 0;
2482 for (VarSymbol var : vars) {
2483 if (var.owner != tree.sym) {
2484 var = new VarSymbol(var.flags_field, var.name, var.type, tree.sym);
2485 }
2486 getterMethHandles[index] = var.asMethodHandle(true);
2487 index++;
2488 }
2489
2490 tree.defs = tree.defs.appendList(generateMandatedAccessors(tree));
2491 tree.defs = tree.defs.appendList(List.of(
2492 generateRecordMethod(tree, names.toString, vars, getterMethHandles),
2493 generateRecordMethod(tree, names.hashCode, vars, getterMethHandles),
2494 generateRecordMethod(tree, names.equals, vars, getterMethHandles)
2495 ));
2496 }
2497
2498 JCTree generateRecordMethod(JCClassDecl tree, Name name, List<VarSymbol> vars, MethodHandleSymbol[] getterMethHandles) {
2499 make_at(tree.pos());
2500 boolean isEquals = name == names.equals;
2501 MethodSymbol msym = lookupMethod(tree.pos(),
2502 name,
2503 tree.sym.type,
2504 isEquals ? List.of(syms.objectType) : List.nil());
2505 // compiler generated methods have the record flag set, user defined ones dont
2506 if ((msym.flags() & RECORD) != 0) {
2507 /* class java.lang.runtime.ObjectMethods provides a common bootstrap that provides a customized implementation
2508 * for methods: toString, hashCode and equals. Here we just need to generate and indy call to:
2509 * java.lang.runtime.ObjectMethods::bootstrap and provide: the record class, the record component names and
2510 * the accessors.
2511 */
2512 Name bootstrapName = names.bootstrap;
2513 LoadableConstant[] staticArgsValues = new LoadableConstant[2 + getterMethHandles.length];
2514 staticArgsValues[0] = (ClassType)tree.sym.type;
2515 String concatNames = vars.stream()
2516 .map(v -> v.name)
2517 .collect(Collectors.joining(";", "", ""));
2518 staticArgsValues[1] = LoadableConstant.String(concatNames);
2519 int index = 2;
2520 for (MethodHandleSymbol mho : getterMethHandles) {
2521 staticArgsValues[index] = mho;
2522 index++;
2523 }
2524
2525 List<Type> staticArgTypes = List.of(syms.classType,
2526 syms.stringType,
2527 new ArrayType(syms.methodHandleType, syms.arrayClass));
2528
2529 JCFieldAccess qualifier = makeIndyQualifier(syms.objectMethodsType, tree, msym,
2530 List.of(syms.methodHandleLookupType,
2531 syms.stringType,
2532 syms.typeDescriptorType).appendList(staticArgTypes),
2533 staticArgsValues, bootstrapName, name, false);
2534
2535 VarSymbol _this = new VarSymbol(SYNTHETIC, names._this, tree.sym.type, tree.sym);
2536
2537 JCMethodInvocation proxyCall;
2538 if (!isEquals) {
2539 proxyCall = make.Apply(List.nil(), qualifier, List.of(make.Ident(_this)));
2540 } else {
2541 VarSymbol o = msym.params.head;
2542 o.adr = 0;
2543 proxyCall = make.Apply(List.nil(), qualifier, List.of(make.Ident(_this), make.Ident(o)));
2544 }
2545 proxyCall.type = qualifier.type;
2546 return make.MethodDef(msym, make.Block(0, List.of(make.Return(proxyCall))));
2547 } else {
2548 return make.Block(SYNTHETIC, List.nil());
2549 }
2550 }
2551
2552 private String argsTypeSig(List<Type> typeList) {
2553 LowerSignatureGenerator sg = new LowerSignatureGenerator();
2554 sg.assembleSig(typeList);
2555 return sg.toString();
2556 }
2557
2558 /**
2559 * Signature Generation
2560 */
2561 private class LowerSignatureGenerator extends Types.SignatureGenerator {
2562
2563 /**
2564 * An output buffer for type signatures.
2565 */
2566 StringBuilder sb = new StringBuilder();
2567
2568 LowerSignatureGenerator() {
2569 types.super();
2570 }
2571
2572 @Override
2573 protected void append(char ch) {
2574 sb.append(ch);
2575 }
2576
2577 @Override
2578 protected void append(byte[] ba) {
2579 sb.append(new String(ba));
2580 }
2581
2582 @Override
2583 protected void append(Name name) {
2584 sb.append(name.toString());
2585 }
2586
2587 @Override
2588 public String toString() {
2589 return sb.toString();
2590 }
2591 }
2592
2593 /**
2594 * Creates an indy qualifier, helpful to be part of an indy invocation
2595 * @param site the site
2596 * @param tree a class declaration tree
2597 * @param msym the method symbol
2598 * @param staticArgTypes the static argument types
2599 * @param staticArgValues the static argument values
2600 * @param bootstrapName the bootstrap name to look for
2601 * @param argName normally bootstraps receives a method name as second argument, if you want that name
2602 * to be different to that of the bootstrap name pass a different name here
2603 * @param isStatic is it static or not
2604 * @return a field access tree
2605 */
2606 JCFieldAccess makeIndyQualifier(
2607 Type site,
2608 JCClassDecl tree,
2609 MethodSymbol msym,
2610 List<Type> staticArgTypes,
2611 LoadableConstant[] staticArgValues,
2612 Name bootstrapName,
2613 Name argName,
2614 boolean isStatic) {
2615 MethodSymbol bsm = rs.resolveInternalMethod(tree.pos(), attrEnv, site,
2616 bootstrapName, staticArgTypes, List.nil());
2617
2618 MethodType indyType = msym.type.asMethodType();
2619 indyType = new MethodType(
2620 isStatic ? List.nil() : indyType.argtypes.prepend(tree.sym.type),
2621 indyType.restype,
2622 indyType.thrown,
2623 syms.methodClass
2624 );
2625 DynamicMethodSymbol dynSym = new DynamicMethodSymbol(argName,
2626 syms.noSymbol,
2627 bsm.asHandle(),
2628 indyType,
2629 staticArgValues);
2630 JCFieldAccess qualifier = make.Select(make.QualIdent(site.tsym), argName);
2631 qualifier.sym = dynSym;
2632 qualifier.type = msym.type.asMethodType().restype;
2633 return qualifier;
2634 }
2635
2636 public void visitMethodDef(JCMethodDecl tree) {
2637 if (tree.name == names.init && (currentClass.flags_field&ENUM) != 0) {
2638 // Add "String $enum$name, int $enum$ordinal" to the beginning of the
2639 // argument list for each constructor of an enum.
2640 JCVariableDecl nameParam = make_at(tree.pos()).
2641 Param(names.fromString(target.syntheticNameChar() +
2642 "enum" + target.syntheticNameChar() + "name"),
2643 syms.stringType, tree.sym);
2644 nameParam.mods.flags |= SYNTHETIC; nameParam.sym.flags_field |= SYNTHETIC;
2645 JCVariableDecl ordParam = make.
2646 Param(names.fromString(target.syntheticNameChar() +
2647 "enum" + target.syntheticNameChar() +
2648 "ordinal"),
2649 syms.intType, tree.sym);
2650 ordParam.mods.flags |= SYNTHETIC; ordParam.sym.flags_field |= SYNTHETIC;
2651
2652 MethodSymbol m = tree.sym;
2653 tree.params = tree.params.prepend(ordParam).prepend(nameParam);
2654
2655 m.extraParams = m.extraParams.prepend(ordParam.sym);
2656 m.extraParams = m.extraParams.prepend(nameParam.sym);
2657 Type olderasure = m.erasure(types);
2658 m.erasure_field = new MethodType(
2659 olderasure.getParameterTypes().prepend(syms.intType).prepend(syms.stringType),
2660 olderasure.getReturnType(),
2661 olderasure.getThrownTypes(),
2662 syms.methodClass);
2663 }
2664
2665 Type prevRestype = currentRestype;
2666 JCMethodDecl prevMethodDef = currentMethodDef;
2667 MethodSymbol prevMethodSym = currentMethodSym;
2668 int prevVariableIndex = variableIndex;
2669 try {
2670 currentRestype = types.erasure(tree.type.getReturnType());
2671 currentMethodDef = tree;
2672 currentMethodSym = tree.sym;
2673 variableIndex = 0;
2674 visitMethodDefInternal(tree);
2675 } finally {
2676 currentRestype = prevRestype;
2677 currentMethodDef = prevMethodDef;
2678 currentMethodSym = prevMethodSym;
2679 variableIndex = prevVariableIndex;
2680 }
2681 }
2682
2683 private void visitMethodDefInternal(JCMethodDecl tree) {
2684 if (tree.name == names.init &&
2685 !currentClass.isStatic() &&
2686 (currentClass.isInner() || currentClass.isDirectlyOrIndirectlyLocal())) {
2687 // We are seeing a constructor of an inner class.
2688 MethodSymbol m = tree.sym;
2689
2690 // Push a new proxy scope for constructor parameters.
2691 // and create definitions for any this$n and proxy parameters.
2692 Map<Symbol, Symbol> prevProxies = proxies;
2693 proxies = new HashMap<>(proxies);
2694 List<VarSymbol> prevOuterThisStack = outerThisStack;
2695 List<VarSymbol> fvs = freevars(currentClass);
2696 JCVariableDecl otdef = null;
2697 if (currentClass.hasOuterInstance())
2698 otdef = outerThisDef(tree.pos, m);
2699 List<JCVariableDecl> fvdefs = freevarDefs(tree.pos, fvs, m, PARAMETER);
2700
2701 // Recursively translate result type, parameters and thrown list.
2702 tree.restype = translate(tree.restype);
2703 tree.params = translateVarDefs(tree.params);
2704 tree.thrown = translate(tree.thrown);
2705
2706 // when compiling stubs, don't process body
2707 if (tree.body == null) {
2708 result = tree;
2709 return;
2710 }
2711
2712 // Add this$n (if needed) in front of and free variables behind
2713 // constructor parameter list.
2714 tree.params = tree.params.appendList(fvdefs);
2715 if (currentClass.hasOuterInstance()) {
2716 tree.params = tree.params.prepend(otdef);
2717 }
2718
2719 // Determine whether this constructor has a super() invocation
2720 boolean invokesSuper = TreeInfo.hasConstructorCall(tree, names._super);
2721
2722 // Create initializers for this$n and proxies
2723 ListBuffer<JCStatement> added = new ListBuffer<>();
2724 if (fvs.nonEmpty()) {
2725 List<Type> addedargtypes = List.nil();
2726 for (List<VarSymbol> l = fvs; l.nonEmpty(); l = l.tail) {
2727 m.capturedLocals =
2728 m.capturedLocals.prepend((VarSymbol)
2729 (proxies.get(l.head)));
2730 if (invokesSuper) {
2731 added = added.prepend(
2732 initField(tree.body.pos, proxies.get(l.head), prevProxies.get(l.head)));
2733 }
2734 addedargtypes = addedargtypes.prepend(l.head.erasure(types));
2735 }
2736 Type olderasure = m.erasure(types);
2737 m.erasure_field = new MethodType(
2738 olderasure.getParameterTypes().appendList(addedargtypes),
2739 olderasure.getReturnType(),
2740 olderasure.getThrownTypes(),
2741 syms.methodClass);
2742 }
2743
2744 // Recursively translate existing local statements
2745 tree.body.stats = translate(tree.body.stats);
2746
2747 // Prepend initializers in front of super() call
2748 if (added.nonEmpty()) {
2749 List<JCStatement> initializers = added.toList();
2750 TreeInfo.mapSuperCalls(tree.body, supercall -> make.Block(0, initializers.append(supercall)));
2751 }
2752
2753 // pop local variables from proxy stack
2754 proxies = prevProxies;
2755
2756 outerThisStack = prevOuterThisStack;
2757 } else {
2758 super.visitMethodDef(tree);
2759 }
2760 if (tree.name == names.init && ((tree.sym.flags_field & Flags.COMPACT_RECORD_CONSTRUCTOR) != 0 ||
2761 (tree.sym.flags_field & (GENERATEDCONSTR | RECORD)) == (GENERATEDCONSTR | RECORD))) {
2762 // lets find out if there is any field waiting to be initialized
2763 ListBuffer<VarSymbol> fields = new ListBuffer<>();
2764 for (Symbol sym : currentClass.getEnclosedElements()) {
2765 if (sym.kind == Kinds.Kind.VAR && ((sym.flags() & RECORD) != 0))
2766 fields.append((VarSymbol) sym);
2767 }
2768 ListBuffer<JCStatement> initializers = new ListBuffer<>();
2769 for (VarSymbol field: fields) {
2770 if ((field.flags_field & Flags.UNINITIALIZED_FIELD) != 0) {
2771 VarSymbol param = tree.params.stream().filter(p -> p.name == field.name).findFirst().get().sym;
2772 make.at(tree.pos);
2773 initializers.add(make.Exec(
2774 make.Assign(
2775 make.Select(make.This(field.owner.erasure(types)), field),
2776 make.Ident(param)).setType(field.erasure(types))));
2777 field.flags_field &= ~Flags.UNINITIALIZED_FIELD;
2778 }
2779 }
2780 if (initializers.nonEmpty()) {
2781 if (allowValueClasses && (tree.sym.owner.isValueClass() || ((ClassSymbol)tree.sym.owner).isRecord())) {
2782 TreeInfo.mapSuperCalls(tree.body, supercall -> make.Block(0, initializers.toList().append(supercall)));
2783 } else {
2784 tree.body.stats = tree.body.stats.appendList(initializers);
2785 }
2786 }
2787 }
2788 result = tree;
2789 }
2790
2791 public void visitTypeCast(JCTypeCast tree) {
2792 tree.clazz = translate(tree.clazz);
2793 if (tree.type.isPrimitive() != tree.expr.type.isPrimitive())
2794 tree.expr = translate(tree.expr, tree.type);
2795 else
2796 tree.expr = translate(tree.expr);
2797 result = tree;
2798 }
2799
2800 /**
2801 * All the exactness checks between primitive types that require a run-time
2802 * check are in {@code java.lang.runtime.ExactConversionsSupport}. Those methods
2803 * are in the form {@code ExactConversionsSupport.is<S>To<T>Exact} where both
2804 * {@code S} and {@code T} are primitive types and correspond to the runtime
2805 * action that will be executed to check whether a certain value (that is passed
2806 * as a parameter) can be converted to {@code T} without loss of information.
2807 *
2808 * Rewrite {@code instanceof if expr : Object} and Type is primitive type:
2809 *
2810 * {@snippet :
2811 * Object v = ...
2812 * if (v instanceof float)
2813 * =>
2814 * if (let tmp$123 = v; tmp$123 instanceof Float)
2815 * }
2816 *
2817 * Rewrite {@code instanceof if expr : wrapper reference type}
2818 *
2819 * {@snippet :
2820 * Integer v = ...
2821 * if (v instanceof float)
2822 * =>
2823 * if (let tmp$123 = v; tmp$123 != null && ExactConversionsSupport.intToFloatExact(tmp$123.intValue()))
2824 * }
2825 *
2826 * Rewrite {@code instanceof if expr : primitive}
2827 *
2828 * {@snippet :
2829 * int v = ...
2830 * if (v instanceof float)
2831 * =>
2832 * if (let tmp$123 = v; ExactConversionsSupport.intToFloatExact(tmp$123))
2833 * }
2834 *
2835 * More rewritings:
2836 * <ul>
2837 * <li>If the {@code instanceof} check is unconditionally exact rewrite to true.</li>
2838 * <li>If expression type is {@code Byte}, {@code Short}, {@code Integer}, ..., an
2839 * unboxing conversion followed by a widening primitive conversion.</li>
2840 * <li>If expression type is a supertype: {@code Number}, a narrowing reference
2841 * conversion followed by an unboxing conversion.</li>
2842 * </ul>
2843 */
2844 public void visitTypeTest(JCInstanceOf tree) {
2845 if (tree.expr.type.isPrimitive() || tree.pattern.type.isPrimitive()) {
2846 JCStatement prefixStatement;
2847 JCExpression exactnessCheck;
2848 JCExpression instanceOfExpr = translate(tree.expr);
2849
2850 if (types.isUnconditionallyExactTypeBased(tree.expr.type, tree.pattern.type)) {
2851 // instanceOfExpr; true
2852 prefixStatement = make.Exec(instanceOfExpr);
2853 exactnessCheck = make.Literal(BOOLEAN, 1).setType(syms.booleanType.constType(1));
2854 } else if (tree.expr.type.isPrimitive()) {
2855 // ExactConversionSupport.isXxxExact(instanceOfExpr)
2856 prefixStatement = null;
2857 exactnessCheck = getExactnessCheck(tree, instanceOfExpr);
2858 } else if (tree.expr.type.isReference()) {
2859 if (types.isUnconditionallyExactTypeBased(types.unboxedType(tree.expr.type), tree.pattern.type)) {
2860 // instanceOfExpr != null
2861 prefixStatement = null;
2862 exactnessCheck = makeBinary(NE, instanceOfExpr, makeNull());
2863 } else {
2864 // We read the result of instanceOfExpr, so create variable
2865 VarSymbol dollar_s = new VarSymbol(FINAL | SYNTHETIC,
2866 names.fromString("tmp" + variableIndex++ + this.target.syntheticNameChar()),
2867 types.erasure(tree.expr.type),
2868 currentMethodSym);
2869 prefixStatement = make.at(tree.pos())
2870 .VarDef(dollar_s, instanceOfExpr);
2871
2872 JCExpression nullCheck =
2873 makeBinary(NE,
2874 make.Ident(dollar_s),
2875 makeNull());
2876
2877 if (types.unboxedType(tree.expr.type).isPrimitive()) {
2878 exactnessCheck =
2879 makeBinary(AND,
2880 nullCheck,
2881 getExactnessCheck(tree, boxIfNeeded(make.Ident(dollar_s), types.unboxedType(tree.expr.type))));
2882 } else {
2883 exactnessCheck =
2884 makeBinary(AND,
2885 nullCheck,
2886 make.at(tree.pos())
2887 .TypeTest(make.Ident(dollar_s), make.Type(types.boxedClass(tree.pattern.type).type))
2888 .setType(syms.booleanType));
2889 }
2890 }
2891 } else {
2892 throw Assert.error("Non primitive or reference type: " + tree.expr.type);
2893 }
2894 result = (prefixStatement == null ? exactnessCheck : make.LetExpr(List.of(prefixStatement), exactnessCheck))
2895 .setType(syms.booleanType);
2896 } else {
2897 tree.expr = translate(tree.expr);
2898 tree.pattern = translate(tree.pattern);
2899 result = tree;
2900 }
2901 }
2902
2903 // TypePairs should be in sync with the corresponding record in SwitchBootstraps
2904 record TypePairs(TypeSymbol from, TypeSymbol to) {
2905 public static TypePairs of(Symtab syms, Type from, Type to) {
2906 if (from == syms.byteType || from == syms.shortType || from == syms.charType) {
2907 from = syms.intType;
2908 }
2909 return new TypePairs(from, to);
2910 }
2911
2912 public TypePairs(Type from, Type to) {
2913 this(from.tsym, to.tsym);
2914 }
2915
2916 public static HashMap<TypePairs, String> initialize(Symtab syms) {
2917 HashMap<TypePairs, String> typePairToName = new HashMap<>();
2918 typePairToName.put(new TypePairs(syms.byteType, syms.charType), "isIntToCharExact"); // redirected
2919 typePairToName.put(new TypePairs(syms.shortType, syms.byteType), "isIntToByteExact"); // redirected
2920 typePairToName.put(new TypePairs(syms.shortType, syms.charType), "isIntToCharExact"); // redirected
2921 typePairToName.put(new TypePairs(syms.charType, syms.byteType), "isIntToByteExact"); // redirected
2922 typePairToName.put(new TypePairs(syms.charType, syms.shortType), "isIntToShortExact"); // redirected
2923 typePairToName.put(new TypePairs(syms.intType, syms.byteType), "isIntToByteExact");
2924 typePairToName.put(new TypePairs(syms.intType, syms.shortType), "isIntToShortExact");
2925 typePairToName.put(new TypePairs(syms.intType, syms.charType), "isIntToCharExact");
2926 typePairToName.put(new TypePairs(syms.intType, syms.floatType), "isIntToFloatExact");
2927 typePairToName.put(new TypePairs(syms.longType, syms.byteType), "isLongToByteExact");
2928 typePairToName.put(new TypePairs(syms.longType, syms.shortType), "isLongToShortExact");
2929 typePairToName.put(new TypePairs(syms.longType, syms.charType), "isLongToCharExact");
2930 typePairToName.put(new TypePairs(syms.longType, syms.intType), "isLongToIntExact");
2931 typePairToName.put(new TypePairs(syms.longType, syms.floatType), "isLongToFloatExact");
2932 typePairToName.put(new TypePairs(syms.longType, syms.doubleType), "isLongToDoubleExact");
2933 typePairToName.put(new TypePairs(syms.floatType, syms.byteType), "isFloatToByteExact");
2934 typePairToName.put(new TypePairs(syms.floatType, syms.shortType), "isFloatToShortExact");
2935 typePairToName.put(new TypePairs(syms.floatType, syms.charType), "isFloatToCharExact");
2936 typePairToName.put(new TypePairs(syms.floatType, syms.intType), "isFloatToIntExact");
2937 typePairToName.put(new TypePairs(syms.floatType, syms.longType), "isFloatToLongExact");
2938 typePairToName.put(new TypePairs(syms.doubleType, syms.byteType), "isDoubleToByteExact");
2939 typePairToName.put(new TypePairs(syms.doubleType, syms.shortType), "isDoubleToShortExact");
2940 typePairToName.put(new TypePairs(syms.doubleType, syms.charType), "isDoubleToCharExact");
2941 typePairToName.put(new TypePairs(syms.doubleType, syms.intType), "isDoubleToIntExact");
2942 typePairToName.put(new TypePairs(syms.doubleType, syms.longType), "isDoubleToLongExact");
2943 typePairToName.put(new TypePairs(syms.doubleType, syms.floatType), "isDoubleToFloatExact");
2944 return typePairToName;
2945 }
2946 }
2947
2948 private JCExpression getExactnessCheck(JCInstanceOf tree, JCExpression argument) {
2949 TypePairs pair = TypePairs.of(syms, types.unboxedTypeOrType(tree.expr.type), tree.pattern.type);
2950
2951 Name exactnessFunction = names.fromString(typePairToName.get(pair));
2952
2953 // Resolve the exactness method
2954 Symbol ecsym = lookupMethod(tree.pos(),
2955 exactnessFunction,
2956 syms.exactConversionsSupportType,
2957 List.of(pair.from.type));
2958
2959 // Generate the method call ExactnessChecks.<exactness method>(<argument>);
2960 JCFieldAccess select = make.Select(
2961 make.QualIdent(syms.exactConversionsSupportType.tsym),
2962 exactnessFunction);
2963 select.sym = ecsym;
2964 select.setType(syms.booleanType);
2965
2966 JCExpression exactnessCheck = make.Apply(List.nil(),
2967 select,
2968 List.of(argument));
2969 exactnessCheck.setType(syms.booleanType);
2970 return exactnessCheck;
2971 }
2972
2973 public void visitNewClass(JCNewClass tree) {
2974 ClassSymbol c = (ClassSymbol)tree.constructor.owner;
2975
2976 // Box arguments, if necessary
2977 boolean isEnum = (tree.constructor.owner.flags() & ENUM) != 0;
2978 List<Type> argTypes = tree.constructor.type.getParameterTypes();
2979 if (isEnum) argTypes = argTypes.prepend(syms.intType).prepend(syms.stringType);
2980 tree.args = boxArgs(argTypes, tree.args, tree.varargsElement);
2981 tree.varargsElement = null;
2982
2983 // If created class is local, add free variables after
2984 // explicit constructor arguments.
2985 if (c.isDirectlyOrIndirectlyLocal() && !c.isStatic()) {
2986 tree.args = tree.args.appendList(loadFreevars(tree.pos(), freevars(c)));
2987 }
2988
2989 // If an access constructor is used, append null as a last argument.
2990 Symbol constructor = accessConstructor(tree.pos(), tree.constructor);
2991 if (constructor != tree.constructor) {
2992 tree.args = tree.args.append(makeNull());
2993 tree.constructor = constructor;
2994 }
2995
2996 // If created class has an outer instance, and new is qualified, pass
2997 // qualifier as first argument. If new is not qualified, pass the
2998 // correct outer instance as first argument.
2999 if (c.hasOuterInstance()) {
3000 JCExpression thisArg;
3001 if (tree.encl != null) {
3002 thisArg = attr.makeNullCheck(translate(tree.encl));
3003 thisArg.type = tree.encl.type;
3004 } else if (c.isDirectlyOrIndirectlyLocal()) {
3005 // local class
3006 thisArg = makeThis(tree.pos(), c.innermostAccessibleEnclosingClass());
3007 } else {
3008 // nested class
3009 thisArg = makeOwnerThis(tree.pos(), c, false);
3010 if (currentMethodSym != null &&
3011 ((currentMethodSym.flags_field & (STATIC | BLOCK)) == BLOCK) &&
3012 currentMethodSym.owner.isValueClass()) {
3013 // instance initializer in a value class
3014 Set<JCExpression> outerThisSet = initializerOuterThis.get(currentClass);
3015 if (outerThisSet == null) {
3016 outerThisSet = new HashSet<>();
3017 }
3018 outerThisSet.add(thisArg);
3019 initializerOuterThis.put(currentClass, outerThisSet);
3020 }
3021 }
3022 tree.args = tree.args.prepend(thisArg);
3023 }
3024 tree.encl = null;
3025
3026 // If we have an anonymous class, create its flat version, rather
3027 // than the class or interface following new.
3028 if (tree.def != null) {
3029 translate(tree.def);
3030
3031 tree.clazz = access(make_at(tree.clazz.pos()).Ident(tree.def.sym));
3032 tree.def = null;
3033 } else {
3034 tree.clazz = access(c, tree.clazz, enclOp, false);
3035 }
3036 result = tree;
3037 }
3038
3039 // Simplify conditionals with known constant controlling expressions.
3040 // This allows us to avoid generating supporting declarations for
3041 // the dead code, which will not be eliminated during code generation.
3042 // Note that Flow.isFalse and Flow.isTrue only return true
3043 // for constant expressions in the sense of JLS 15.27, which
3044 // are guaranteed to have no side-effects. More aggressive
3045 // constant propagation would require that we take care to
3046 // preserve possible side-effects in the condition expression.
3047
3048 // One common case is equality expressions involving a constant and null.
3049 // Since null is not a constant expression (because null cannot be
3050 // represented in the constant pool), equality checks involving null are
3051 // not captured by Flow.isTrue/isFalse.
3052 // Equality checks involving a constant and null, e.g.
3053 // "" == null
3054 // are safe to simplify as no side-effects can occur.
3055
3056 private boolean isTrue(JCTree exp) {
3057 if (exp.type.isTrue())
3058 return true;
3059 Boolean b = expValue(exp);
3060 return b == null ? false : b;
3061 }
3062 private boolean isFalse(JCTree exp) {
3063 if (exp.type.isFalse())
3064 return true;
3065 Boolean b = expValue(exp);
3066 return b == null ? false : !b;
3067 }
3068 /* look for (in)equality relations involving null.
3069 * return true - if expression is always true
3070 * false - if expression is always false
3071 * null - if expression cannot be eliminated
3072 */
3073 private Boolean expValue(JCTree exp) {
3074 while (exp.hasTag(PARENS))
3075 exp = ((JCParens)exp).expr;
3076
3077 boolean eq;
3078 switch (exp.getTag()) {
3079 case EQ: eq = true; break;
3080 case NE: eq = false; break;
3081 default:
3082 return null;
3083 }
3084
3085 // we have a JCBinary(EQ|NE)
3086 // check if we have two literals (constants or null)
3087 JCBinary b = (JCBinary)exp;
3088 if (b.lhs.type.hasTag(BOT)) return expValueIsNull(eq, b.rhs);
3089 if (b.rhs.type.hasTag(BOT)) return expValueIsNull(eq, b.lhs);
3090 return null;
3091 }
3092 private Boolean expValueIsNull(boolean eq, JCTree t) {
3093 if (t.type.hasTag(BOT)) return Boolean.valueOf(eq);
3094 if (t.hasTag(LITERAL)) return Boolean.valueOf(!eq);
3095 return null;
3096 }
3097
3098 /** Visitor method for conditional expressions.
3099 */
3100 @Override
3101 public void visitConditional(JCConditional tree) {
3102 JCTree cond = tree.cond = translate(tree.cond, syms.booleanType);
3103 if (isTrue(cond) && noClassDefIn(tree.falsepart)) {
3104 result = convert(translate(tree.truepart, tree.type), tree.type);
3105 addPrunedInfo(cond);
3106 } else if (isFalse(cond) && noClassDefIn(tree.truepart)) {
3107 result = convert(translate(tree.falsepart, tree.type), tree.type);
3108 addPrunedInfo(cond);
3109 } else {
3110 // Condition is not a compile-time constant.
3111 tree.truepart = translate(tree.truepart, tree.type);
3112 tree.falsepart = translate(tree.falsepart, tree.type);
3113 result = tree;
3114 }
3115 }
3116 //where
3117 private JCExpression convert(JCExpression tree, Type pt) {
3118 if (tree.type == pt || tree.type.hasTag(BOT))
3119 return tree;
3120 JCExpression result = make_at(tree.pos()).TypeCast(make.Type(pt), tree);
3121 result.type = (tree.type.constValue() != null) ? cfolder.coerce(tree.type, pt)
3122 : pt;
3123 return result;
3124 }
3125
3126 /** Visitor method for if statements.
3127 */
3128 public void visitIf(JCIf tree) {
3129 JCTree cond = tree.cond = translate(tree.cond, syms.booleanType);
3130 if (isTrue(cond) && noClassDefIn(tree.elsepart)) {
3131 result = translate(tree.thenpart);
3132 addPrunedInfo(cond);
3133 } else if (isFalse(cond) && noClassDefIn(tree.thenpart)) {
3134 if (tree.elsepart != null) {
3135 result = translate(tree.elsepart);
3136 } else {
3137 result = make.Skip();
3138 }
3139 addPrunedInfo(cond);
3140 } else {
3141 // Condition is not a compile-time constant.
3142 tree.thenpart = translate(tree.thenpart);
3143 tree.elsepart = translate(tree.elsepart);
3144 result = tree;
3145 }
3146 }
3147
3148 /** Visitor method for assert statements. Translate them away.
3149 */
3150 public void visitAssert(JCAssert tree) {
3151 tree.cond = translate(tree.cond, syms.booleanType);
3152 if (!tree.cond.type.isTrue()) {
3153 JCExpression cond = assertFlagTest(tree.pos());
3154 List<JCExpression> exnArgs = (tree.detail == null) ?
3155 List.nil() : List.of(translate(tree.detail));
3156 if (!tree.cond.type.isFalse()) {
3157 cond = makeBinary
3158 (AND,
3159 cond,
3160 makeUnary(NOT, tree.cond));
3161 }
3162 result =
3163 make.If(cond,
3164 make_at(tree).
3165 Throw(makeNewClass(syms.assertionErrorType, exnArgs)),
3166 null);
3167 } else {
3168 result = make.Skip();
3169 }
3170 }
3171
3172 public void visitApply(JCMethodInvocation tree) {
3173 Symbol meth = TreeInfo.symbol(tree.meth);
3174 List<Type> argtypes = meth.type.getParameterTypes();
3175 if (meth.name == names.init && meth.owner == syms.enumSym)
3176 argtypes = argtypes.tail.tail;
3177 tree.args = boxArgs(argtypes, tree.args, tree.varargsElement);
3178 tree.varargsElement = null;
3179 Name methName = TreeInfo.name(tree.meth);
3180 if (meth.name==names.init) {
3181 // We are seeing a this(...) or super(...) constructor call.
3182 // If an access constructor is used, append null as a last argument.
3183 Symbol constructor = accessConstructor(tree.pos(), meth);
3184 if (constructor != meth) {
3185 tree.args = tree.args.append(makeNull());
3186 TreeInfo.setSymbol(tree.meth, constructor);
3187 }
3188
3189 // If we are calling a constructor of a local class, add
3190 // free variables after explicit constructor arguments.
3191 ClassSymbol c = (ClassSymbol)constructor.owner;
3192 if (c.isDirectlyOrIndirectlyLocal() && !c.isStatic()) {
3193 tree.args = tree.args.appendList(loadFreevars(tree.pos(), freevars(c)));
3194 }
3195
3196 // If we are calling a constructor of an enum class, pass
3197 // along the name and ordinal arguments
3198 if ((c.flags_field&ENUM) != 0 || c.getQualifiedName() == names.java_lang_Enum) {
3199 List<JCVariableDecl> params = currentMethodDef.params;
3200 if (currentMethodSym.owner.hasOuterInstance())
3201 params = params.tail; // drop this$n
3202 tree.args = tree.args
3203 .prepend(make_at(tree.pos()).Ident(params.tail.head.sym)) // ordinal
3204 .prepend(make.Ident(params.head.sym)); // name
3205 }
3206
3207 // If we are calling a constructor of a class with an outer
3208 // instance, and the call
3209 // is qualified, pass qualifier as first argument in front of
3210 // the explicit constructor arguments. If the call
3211 // is not qualified, pass the correct outer instance as
3212 // first argument. If we are a static class, there is no
3213 // such outer instance, so generate an error.
3214 if (c.hasOuterInstance()) {
3215 JCExpression thisArg;
3216 if (tree.meth.hasTag(SELECT)) {
3217 thisArg = attr.
3218 makeNullCheck(translate(((JCFieldAccess) tree.meth).selected));
3219 tree.meth = make.Ident(constructor);
3220 ((JCIdent) tree.meth).name = methName;
3221 } else if (c.isDirectlyOrIndirectlyLocal() || methName == names._this){
3222 // local class or this() call
3223 thisArg = makeThis(tree.meth.pos(), c.innermostAccessibleEnclosingClass());
3224 } else if (currentClass.isStatic()) {
3225 // super() call from static nested class - invalid
3226 log.error(tree.pos(),
3227 Errors.NoEnclInstanceOfTypeInScope(c.type.getEnclosingType().tsym));
3228 thisArg = make.Literal(BOT, null).setType(syms.botType);
3229 } else {
3230 // super() call of nested class - never pick 'this'
3231 thisArg = makeOwnerThisN(tree.meth.pos(), c, false);
3232 }
3233 tree.args = tree.args.prepend(thisArg);
3234 }
3235 } else {
3236 // We are seeing a normal method invocation; translate this as usual.
3237 tree.meth = translate(tree.meth);
3238
3239 // If the translated method itself is an Apply tree, we are
3240 // seeing an access method invocation. In this case, append
3241 // the method arguments to the arguments of the access method.
3242 if (tree.meth.hasTag(APPLY)) {
3243 JCMethodInvocation app = (JCMethodInvocation)tree.meth;
3244 app.args = tree.args.prependList(app.args);
3245 result = app;
3246 return;
3247 }
3248 }
3249 if (tree.args.stream().anyMatch(c -> c == null)) {
3250 throw new AssertionError("Whooops before: " + tree);
3251 }
3252 result = tree;
3253 }
3254
3255 List<JCExpression> boxArgs(List<Type> parameters, List<JCExpression> _args, Type varargsElement) {
3256 List<JCExpression> args = _args;
3257 if (parameters.isEmpty()) return args;
3258 boolean anyChanges = false;
3259 ListBuffer<JCExpression> result = new ListBuffer<>();
3260 while (parameters.tail.nonEmpty()) {
3261 JCExpression arg = translate(args.head, parameters.head);
3262 anyChanges |= (arg != args.head);
3263 result.append(arg);
3264 args = args.tail;
3265 parameters = parameters.tail;
3266 }
3267 Type parameter = parameters.head;
3268 if (varargsElement != null) {
3269 anyChanges = true;
3270 ListBuffer<JCExpression> elems = new ListBuffer<>();
3271 while (args.nonEmpty()) {
3272 JCExpression arg = translate(args.head, varargsElement);
3273 elems.append(arg);
3274 args = args.tail;
3275 }
3276 JCNewArray boxedArgs = make.NewArray(make.Type(varargsElement),
3277 List.nil(),
3278 elems.toList());
3279 boxedArgs.type = new ArrayType(varargsElement, syms.arrayClass);
3280 result.append(boxedArgs);
3281 } else {
3282 if (args.length() != 1) throw new AssertionError(args);
3283 JCExpression arg = translate(args.head, parameter);
3284 anyChanges |= (arg != args.head);
3285 result.append(arg);
3286 if (!anyChanges) return _args;
3287 }
3288 return result.toList();
3289 }
3290
3291 /** Expand a boxing or unboxing conversion if needed. */
3292 @SuppressWarnings("unchecked") // XXX unchecked
3293 <T extends JCExpression> T boxIfNeeded(T tree, Type type) {
3294 Assert.check(!type.hasTag(VOID));
3295 if (type.hasTag(NONE))
3296 return tree;
3297 boolean havePrimitive = tree.type.isPrimitive();
3298 if (havePrimitive == type.isPrimitive())
3299 return tree;
3300 if (havePrimitive) {
3301 Type unboxedTarget = types.unboxedType(type);
3302 if (!unboxedTarget.hasTag(NONE)) {
3303 if (!types.isSubtype(tree.type, unboxedTarget)) //e.g. Character c = 89;
3304 tree.type = unboxedTarget.constType(tree.type.constValue());
3305 return (T)boxPrimitive(tree, types.erasure(type));
3306 } else {
3307 tree = (T)boxPrimitive(tree);
3308 }
3309 } else {
3310 tree = (T)unbox(tree, type);
3311 }
3312 return tree;
3313 }
3314
3315 /** Box up a single primitive expression. */
3316 JCExpression boxPrimitive(JCExpression tree) {
3317 return boxPrimitive(tree, types.boxedClass(tree.type).type);
3318 }
3319
3320 /** Box up a single primitive expression. */
3321 JCExpression boxPrimitive(JCExpression tree, Type box) {
3322 make_at(tree.pos());
3323 Symbol valueOfSym = lookupMethod(tree.pos(),
3324 names.valueOf,
3325 box,
3326 List.<Type>nil()
3327 .prepend(tree.type));
3328 return make.App(make.QualIdent(valueOfSym), List.of(tree));
3329 }
3330
3331 /** Unbox an object to a primitive value. */
3332 JCExpression unbox(JCExpression tree, Type primitive) {
3333 Type unboxedType = types.unboxedType(tree.type);
3334 if (unboxedType.hasTag(NONE)) {
3335 unboxedType = primitive;
3336 if (!unboxedType.isPrimitive())
3337 throw new AssertionError(unboxedType);
3338 make_at(tree.pos());
3339 tree = make.TypeCast(types.boxedClass(unboxedType).type, tree);
3340 } else {
3341 // There must be a conversion from unboxedType to primitive.
3342 if (!types.isSubtype(unboxedType, primitive))
3343 throw new AssertionError(tree);
3344 }
3345 make_at(tree.pos());
3346 Symbol valueSym = lookupMethod(tree.pos(),
3347 unboxedType.tsym.name.append(names.Value), // x.intValue()
3348 tree.type,
3349 List.nil());
3350 return make.App(make.Select(tree, valueSym));
3351 }
3352
3353 /** Visitor method for parenthesized expressions.
3354 * If the subexpression has changed, omit the parens.
3355 */
3356 public void visitParens(JCParens tree) {
3357 JCTree expr = translate(tree.expr);
3358 result = ((expr == tree.expr) ? tree : expr);
3359 }
3360
3361 public void visitIndexed(JCArrayAccess tree) {
3362 tree.indexed = translate(tree.indexed);
3363 tree.index = translate(tree.index, syms.intType);
3364 result = tree;
3365 }
3366
3367 public void visitAssign(JCAssign tree) {
3368 tree.lhs = translate(tree.lhs, tree);
3369 tree.rhs = translate(tree.rhs, tree.lhs.type);
3370
3371 // If translated left hand side is an Apply, we are
3372 // seeing an access method invocation. In this case, append
3373 // right hand side as last argument of the access method.
3374 if (tree.lhs.hasTag(APPLY)) {
3375 JCMethodInvocation app = (JCMethodInvocation)tree.lhs;
3376 app.args = List.of(tree.rhs).prependList(app.args);
3377 result = app;
3378 } else {
3379 result = tree;
3380 }
3381 }
3382
3383 public void visitAssignop(final JCAssignOp tree) {
3384 final boolean boxingReq = !tree.lhs.type.isPrimitive() &&
3385 tree.operator.type.getReturnType().isPrimitive();
3386
3387 AssignopDependencyScanner depScanner = new AssignopDependencyScanner(tree);
3388 depScanner.scan(tree.rhs);
3389
3390 if (boxingReq || depScanner.dependencyFound) {
3391 // boxing required; need to rewrite as x = (unbox typeof x)(x op y);
3392 // or if x == (typeof x)z then z = (unbox typeof x)((typeof x)z op y)
3393 // (but without recomputing x)
3394 JCTree newTree = abstractLval(tree.lhs, lhs -> {
3395 Tag newTag = tree.getTag().noAssignOp();
3396 // Erasure (TransTypes) can change the type of
3397 // tree.lhs. However, we can still get the
3398 // unerased type of tree.lhs as it is stored
3399 // in tree.type in Attr.
3400 OperatorSymbol newOperator = operators.resolveBinary(tree,
3401 newTag,
3402 tree.type,
3403 tree.rhs.type);
3404 //Need to use the "lhs" at two places, once on the future left hand side
3405 //and once in the future binary operator. But further processing may change
3406 //the components of the tree in place (see visitSelect for e.g. <Class>.super.<ident>),
3407 //so cloning the tree to avoid interference between the uses:
3408 JCExpression expr = (JCExpression) lhs.clone();
3409 if (expr.type != tree.type)
3410 expr = make.TypeCast(tree.type, expr);
3411 JCBinary opResult = make.Binary(newTag, expr, tree.rhs);
3412 opResult.operator = newOperator;
3413 opResult.type = newOperator.type.getReturnType();
3414 JCExpression newRhs = boxingReq ?
3415 make.TypeCast(types.unboxedType(tree.type), opResult) :
3416 opResult;
3417 return make.Assign(lhs, newRhs).setType(tree.type);
3418 });
3419 result = translate(newTree);
3420 return;
3421 }
3422 tree.lhs = translate(tree.lhs, tree);
3423 tree.rhs = translate(tree.rhs, tree.operator.type.getParameterTypes().tail.head);
3424
3425 // If translated left hand side is an Apply, we are
3426 // seeing an access method invocation. In this case, append
3427 // right hand side as last argument of the access method.
3428 if (tree.lhs.hasTag(APPLY)) {
3429 JCMethodInvocation app = (JCMethodInvocation)tree.lhs;
3430 // if operation is a += on strings,
3431 // make sure to convert argument to string
3432 JCExpression rhs = tree.operator.opcode == string_add
3433 ? makeString(tree.rhs)
3434 : tree.rhs;
3435 app.args = List.of(rhs).prependList(app.args);
3436 result = app;
3437 } else {
3438 result = tree;
3439 }
3440 }
3441
3442 class AssignopDependencyScanner extends TreeScanner {
3443
3444 Symbol sym;
3445 boolean dependencyFound = false;
3446
3447 AssignopDependencyScanner(JCAssignOp tree) {
3448 this.sym = TreeInfo.symbol(tree.lhs);
3449 }
3450
3451 @Override
3452 public void scan(JCTree tree) {
3453 if (tree != null && sym != null) {
3454 tree.accept(this);
3455 }
3456 }
3457
3458 @Override
3459 public void visitAssignop(JCAssignOp tree) {
3460 if (TreeInfo.symbol(tree.lhs) == sym) {
3461 dependencyFound = true;
3462 return;
3463 }
3464 super.visitAssignop(tree);
3465 }
3466
3467 @Override
3468 public void visitUnary(JCUnary tree) {
3469 if (TreeInfo.symbol(tree.arg) == sym) {
3470 dependencyFound = true;
3471 return;
3472 }
3473 super.visitUnary(tree);
3474 }
3475 }
3476
3477 /** Lower a tree of the form e++ or e-- where e is an object type */
3478 JCExpression lowerBoxedPostop(final JCUnary tree) {
3479 // translate to tmp1=lval(e); tmp2=tmp1; tmp1 OP 1; tmp2
3480 // or
3481 // translate to tmp1=lval(e); tmp2=tmp1; (typeof tree)tmp1 OP 1; tmp2
3482 // where OP is += or -=
3483 final boolean cast = TreeInfo.skipParens(tree.arg).hasTag(TYPECAST);
3484 return abstractLval(tree.arg, tmp1 -> abstractRval(tmp1, tree.arg.type, tmp2 -> {
3485 Tag opcode = (tree.hasTag(POSTINC))
3486 ? PLUS_ASG : MINUS_ASG;
3487 //"tmp1" and "tmp2" may refer to the same instance
3488 //(for e.g. <Class>.super.<ident>). But further processing may
3489 //change the components of the tree in place (see visitSelect),
3490 //so cloning the tree to avoid interference between the two uses:
3491 JCExpression lhs = (JCExpression)tmp1.clone();
3492 lhs = cast
3493 ? make.TypeCast(tree.arg.type, lhs)
3494 : lhs;
3495 JCExpression update = makeAssignop(opcode,
3496 lhs,
3497 make.Literal(1));
3498 return makeComma(update, tmp2);
3499 }));
3500 }
3501
3502 public void visitUnary(JCUnary tree) {
3503 boolean isUpdateOperator = tree.getTag().isIncOrDecUnaryOp();
3504 if (isUpdateOperator && !tree.arg.type.isPrimitive()) {
3505 switch(tree.getTag()) {
3506 case PREINC: // ++ e
3507 // translate to e += 1
3508 case PREDEC: // -- e
3509 // translate to e -= 1
3510 {
3511 JCTree.Tag opcode = (tree.hasTag(PREINC))
3512 ? PLUS_ASG : MINUS_ASG;
3513 JCAssignOp newTree = makeAssignop(opcode,
3514 tree.arg,
3515 make.Literal(1));
3516 result = translate(newTree, tree.type);
3517 return;
3518 }
3519 case POSTINC: // e ++
3520 case POSTDEC: // e --
3521 {
3522 result = translate(lowerBoxedPostop(tree), tree.type);
3523 return;
3524 }
3525 }
3526 throw new AssertionError(tree);
3527 }
3528
3529 tree.arg = boxIfNeeded(translate(tree.arg, tree), tree.type);
3530
3531 if (tree.hasTag(NOT) && tree.arg.type.constValue() != null) {
3532 tree.type = cfolder.fold1(bool_not, tree.arg.type);
3533 }
3534
3535 // If translated left hand side is an Apply, we are
3536 // seeing an access method invocation. In this case, return
3537 // that access method invocation as result.
3538 if (isUpdateOperator && tree.arg.hasTag(APPLY)) {
3539 result = tree.arg;
3540 } else {
3541 result = tree;
3542 }
3543 }
3544
3545 public void visitBinary(JCBinary tree) {
3546 List<Type> formals = tree.operator.type.getParameterTypes();
3547 JCTree lhs = tree.lhs = translate(tree.lhs, formals.head);
3548 switch (tree.getTag()) {
3549 case OR:
3550 if (isTrue(lhs)) {
3551 result = lhs;
3552 return;
3553 }
3554 if (isFalse(lhs)) {
3555 result = translate(tree.rhs, formals.tail.head);
3556 return;
3557 }
3558 break;
3559 case AND:
3560 if (isFalse(lhs)) {
3561 result = lhs;
3562 return;
3563 }
3564 if (isTrue(lhs)) {
3565 result = translate(tree.rhs, formals.tail.head);
3566 return;
3567 }
3568 break;
3569 }
3570 tree.rhs = translate(tree.rhs, formals.tail.head);
3571 result = tree;
3572 }
3573
3574 public void visitIdent(JCIdent tree) {
3575 result = access(tree.sym, tree, enclOp, false);
3576 }
3577
3578 /** Translate away the foreach loop. */
3579 public void visitForeachLoop(JCEnhancedForLoop tree) {
3580 if (types.elemtype(tree.expr.type) == null)
3581 visitIterableForeachLoop(tree);
3582 else
3583 visitArrayForeachLoop(tree);
3584 }
3585 // where
3586 /**
3587 * A statement of the form
3588 *
3589 * <pre>
3590 * for ( T v : arrayexpr ) stmt;
3591 * </pre>
3592 *
3593 * (where arrayexpr is of an array type) gets translated to
3594 *
3595 * <pre>{@code
3596 * for ( { arraytype #arr = arrayexpr;
3597 * int #len = array.length;
3598 * int #i = 0; };
3599 * #i < #len; i$++ ) {
3600 * T v = arr$[#i];
3601 * stmt;
3602 * }
3603 * }</pre>
3604 *
3605 * where #arr, #len, and #i are freshly named synthetic local variables.
3606 */
3607 private void visitArrayForeachLoop(JCEnhancedForLoop tree) {
3608 make_at(tree.expr.pos());
3609 VarSymbol arraycache = new VarSymbol(SYNTHETIC,
3610 names.fromString("arr" + target.syntheticNameChar()),
3611 tree.expr.type,
3612 currentMethodSym);
3613 JCStatement arraycachedef = make.VarDef(arraycache, tree.expr);
3614 VarSymbol lencache = new VarSymbol(SYNTHETIC,
3615 names.fromString("len" + target.syntheticNameChar()),
3616 syms.intType,
3617 currentMethodSym);
3618 JCStatement lencachedef = make.
3619 VarDef(lencache, make.Select(make.Ident(arraycache), syms.lengthVar));
3620 VarSymbol index = new VarSymbol(SYNTHETIC,
3621 names.fromString("i" + target.syntheticNameChar()),
3622 syms.intType,
3623 currentMethodSym);
3624
3625 JCVariableDecl indexdef = make.VarDef(index, make.Literal(INT, 0));
3626 indexdef.init.type = indexdef.type = syms.intType.constType(0);
3627
3628 List<JCStatement> loopinit = List.of(arraycachedef, lencachedef, indexdef);
3629 JCBinary cond = makeBinary(LT, make.Ident(index), make.Ident(lencache));
3630
3631 JCExpressionStatement step = make.Exec(makeUnary(PREINC, make.Ident(index)));
3632
3633 Type elemtype = types.elemtype(tree.expr.type);
3634 JCExpression loopvarinit = make.Indexed(make.Ident(arraycache),
3635 make.Ident(index)).setType(elemtype);
3636 JCVariableDecl loopvardef = (JCVariableDecl)make.VarDef(tree.var.mods,
3637 tree.var.name,
3638 tree.var.vartype,
3639 loopvarinit).setType(tree.var.type);
3640 loopvardef.sym = tree.var.sym;
3641 JCBlock body = make.
3642 Block(0, List.of(loopvardef, tree.body));
3643
3644 result = translate(make.
3645 ForLoop(loopinit,
3646 cond,
3647 List.of(step),
3648 body));
3649 patchTargets(body, tree, result);
3650 }
3651 /** Patch up break and continue targets. */
3652 private void patchTargets(JCTree body, final JCTree src, final JCTree dest) {
3653 class Patcher extends TreeScanner {
3654 public void visitBreak(JCBreak tree) {
3655 if (tree.target == src)
3656 tree.target = dest;
3657 }
3658 public void visitYield(JCYield tree) {
3659 if (tree.target == src)
3660 tree.target = dest;
3661 scan(tree.value);
3662 }
3663 public void visitContinue(JCContinue tree) {
3664 if (tree.target == src)
3665 tree.target = dest;
3666 }
3667 public void visitClassDef(JCClassDecl tree) {}
3668 }
3669 new Patcher().scan(body);
3670 }
3671 /**
3672 * A statement of the form
3673 *
3674 * <pre>
3675 * for ( T v : coll ) stmt ;
3676 * </pre>
3677 *
3678 * (where coll implements {@code Iterable<? extends T>}) gets translated to
3679 *
3680 * <pre>{@code
3681 * for ( Iterator<? extends T> #i = coll.iterator(); #i.hasNext(); ) {
3682 * T v = (T) #i.next();
3683 * stmt;
3684 * }
3685 * }</pre>
3686 *
3687 * where #i is a freshly named synthetic local variable.
3688 */
3689 private void visitIterableForeachLoop(JCEnhancedForLoop tree) {
3690 make_at(tree.expr.pos());
3691 Type iteratorTarget = syms.objectType;
3692 Type iterableType = types.asSuper(types.cvarUpperBound(tree.expr.type),
3693 syms.iterableType.tsym);
3694 if (iterableType.getTypeArguments().nonEmpty())
3695 iteratorTarget = types.erasure(iterableType.getTypeArguments().head);
3696 tree.expr.type = types.erasure(types.skipTypeVars(tree.expr.type, false));
3697 tree.expr = transTypes.coerce(attrEnv, tree.expr, types.erasure(iterableType));
3698 Symbol iterator = lookupMethod(tree.expr.pos(),
3699 names.iterator,
3700 tree.expr.type,
3701 List.nil());
3702 Assert.check(types.isSameType(types.erasure(types.asSuper(iterator.type.getReturnType(), syms.iteratorType.tsym)), types.erasure(syms.iteratorType)));
3703 VarSymbol itvar = new VarSymbol(SYNTHETIC, names.fromString("i" + target.syntheticNameChar()),
3704 types.erasure(syms.iteratorType),
3705 currentMethodSym);
3706
3707 JCStatement init = make.
3708 VarDef(itvar, make.App(make.Select(tree.expr, iterator)
3709 .setType(types.erasure(iterator.type))));
3710
3711 Symbol hasNext = lookupMethod(tree.expr.pos(),
3712 names.hasNext,
3713 itvar.type,
3714 List.nil());
3715 JCMethodInvocation cond = make.App(make.Select(make.Ident(itvar), hasNext));
3716 Symbol next = lookupMethod(tree.expr.pos(),
3717 names.next,
3718 itvar.type,
3719 List.nil());
3720 JCExpression vardefinit = make.App(make.Select(make.Ident(itvar), next));
3721 if (tree.var.type.isPrimitive())
3722 vardefinit = make.TypeCast(types.cvarUpperBound(iteratorTarget), vardefinit);
3723 else
3724 vardefinit = make.TypeCast(tree.var.type, vardefinit);
3725 JCVariableDecl indexDef = (JCVariableDecl)make.VarDef(tree.var.mods,
3726 tree.var.name,
3727 tree.var.vartype,
3728 vardefinit).setType(tree.var.type);
3729 indexDef.sym = tree.var.sym;
3730 JCBlock body = make.Block(0, List.of(indexDef, tree.body));
3731 body.bracePos = TreeInfo.endPos(tree.body);
3732 result = translate(make.
3733 ForLoop(List.of(init),
3734 cond,
3735 List.nil(),
3736 body));
3737 patchTargets(body, tree, result);
3738 }
3739
3740 public void visitVarDef(JCVariableDecl tree) {
3741 MethodSymbol oldMethodSym = currentMethodSym;
3742 int prevVariableIndex = variableIndex;
3743 tree.mods = translate(tree.mods);
3744 tree.vartype = translate(tree.vartype);
3745 if (currentMethodSym == null) {
3746 // A class or instance field initializer.
3747 currentMethodSym =
3748 new MethodSymbol((tree.mods.flags&STATIC) | BLOCK,
3749 names.empty, null,
3750 currentClass);
3751 }
3752 try {
3753 if (tree.init != null) tree.init = translate(tree.init, tree.type);
3754 result = tree;
3755 } finally {
3756 currentMethodSym = oldMethodSym;
3757 variableIndex = prevVariableIndex;
3758 }
3759 }
3760
3761 public void visitBlock(JCBlock tree) {
3762 MethodSymbol oldMethodSym = currentMethodSym;
3763 if (currentMethodSym == null) {
3764 // Block is a static or instance initializer.
3765 currentMethodSym =
3766 new MethodSymbol(tree.flags | BLOCK,
3767 names.empty, null,
3768 currentClass);
3769 }
3770 int prevVariableIndex = variableIndex;
3771 try {
3772 variableIndex = 0;
3773 super.visitBlock(tree);
3774 } finally {
3775 currentMethodSym = oldMethodSym;
3776 variableIndex = prevVariableIndex;
3777 }
3778 }
3779
3780 public void visitDoLoop(JCDoWhileLoop tree) {
3781 tree.body = translate(tree.body);
3782 tree.cond = translate(tree.cond, syms.booleanType);
3783 result = tree;
3784 }
3785
3786 public void visitWhileLoop(JCWhileLoop tree) {
3787 tree.cond = translate(tree.cond, syms.booleanType);
3788 tree.body = translate(tree.body);
3789 result = tree;
3790 }
3791
3792 public void visitForLoop(JCForLoop tree) {
3793 tree.init = translate(tree.init);
3794 if (tree.cond != null)
3795 tree.cond = translate(tree.cond, syms.booleanType);
3796 tree.step = translate(tree.step);
3797 tree.body = translate(tree.body);
3798 result = tree;
3799 }
3800
3801 public void visitReturn(JCReturn tree) {
3802 if (tree.expr != null)
3803 tree.expr = translate(tree.expr,
3804 currentRestype);
3805 result = tree;
3806 }
3807
3808 @Override
3809 public void visitLambda(JCLambda tree) {
3810 Type prevRestype = currentRestype;
3811 try {
3812 currentRestype = types.erasure(tree.getDescriptorType(types)).getReturnType();
3813 // represent void results as NO_TYPE, to avoid unnecessary boxing in boxIfNeeded
3814 if (currentRestype.hasTag(VOID))
3815 currentRestype = Type.noType;
3816 tree.body = tree.getBodyKind() == BodyKind.EXPRESSION ?
3817 translate((JCExpression) tree.body, currentRestype) :
3818 translate(tree.body);
3819 } finally {
3820 currentRestype = prevRestype;
3821 }
3822 result = tree;
3823 }
3824
3825 public void visitSwitch(JCSwitch tree) {
3826 List<JCCase> cases = tree.patternSwitch ? addDefaultIfNeeded(tree.patternSwitch,
3827 tree.wasEnumSelector,
3828 tree.cases)
3829 : tree.cases;
3830 handleSwitch(tree, tree.selector, cases);
3831 }
3832
3833 @Override
3834 public void visitSwitchExpression(JCSwitchExpression tree) {
3835 List<JCCase> cases = addDefaultIfNeeded(tree.patternSwitch, tree.wasEnumSelector, tree.cases);
3836 handleSwitch(tree, tree.selector, cases);
3837 }
3838
3839 private List<JCCase> addDefaultIfNeeded(boolean patternSwitch, boolean wasEnumSelector,
3840 List<JCCase> cases) {
3841 if (cases.stream().flatMap(c -> c.labels.stream()).noneMatch(p -> p.hasTag(Tag.DEFAULTCASELABEL))) {
3842 boolean matchException = useMatchException;
3843 matchException |= patternSwitch && !wasEnumSelector;
3844 Type exception = matchException ? syms.matchExceptionType
3845 : syms.incompatibleClassChangeErrorType;
3846 List<JCExpression> params = matchException ? List.of(makeNull(), makeNull())
3847 : List.nil();
3848 JCThrow thr = make.Throw(makeNewClass(exception, params));
3849 JCCase c = make.Case(JCCase.STATEMENT, List.of(make.DefaultCaseLabel()), null, List.of(thr), null);
3850 cases = cases.prepend(c);
3851 }
3852
3853 return cases;
3854 }
3855
3856 private void handleSwitch(JCTree tree, JCExpression selector, List<JCCase> cases) {
3857 //expand multiple label cases:
3858 ListBuffer<JCCase> convertedCases = new ListBuffer<>();
3859
3860 for (JCCase c : cases) {
3861 switch (c.labels.size()) {
3862 case 0: //default
3863 case 1: //single label
3864 convertedCases.append(c);
3865 break;
3866 default: //multiple labels, expand:
3867 //case C1, C2, C3: ...
3868 //=>
3869 //case C1:
3870 //case C2:
3871 //case C3: ...
3872 List<JCCaseLabel> patterns = c.labels;
3873 while (patterns.tail.nonEmpty()) {
3874 convertedCases.append(make_at(c.pos()).Case(JCCase.STATEMENT,
3875 List.of(patterns.head),
3876 null,
3877 List.nil(),
3878 null));
3879 patterns = patterns.tail;
3880 }
3881 c.labels = patterns;
3882 convertedCases.append(c);
3883 break;
3884 }
3885 }
3886
3887 for (JCCase c : convertedCases) {
3888 if (c.caseKind == JCCase.RULE && c.completesNormally) {
3889 JCBreak b = make.at(TreeInfo.endPos(c.stats.last())).Break(null);
3890 b.target = tree;
3891 c.stats = c.stats.append(b);
3892 }
3893 }
3894
3895 cases = convertedCases.toList();
3896
3897 Type selsuper = types.supertype(selector.type);
3898 boolean enumSwitch = selsuper != null &&
3899 (selector.type.tsym.flags() & ENUM) != 0;
3900 boolean stringSwitch = selsuper != null &&
3901 types.isSameType(selector.type, syms.stringType);
3902 boolean boxedSwitch = !enumSwitch && !stringSwitch && !selector.type.isPrimitive();
3903 selector = translate(selector, selector.type);
3904 cases = translateCases(cases);
3905 if (tree.hasTag(SWITCH)) {
3906 ((JCSwitch) tree).selector = selector;
3907 ((JCSwitch) tree).cases = cases;
3908 } else if (tree.hasTag(SWITCH_EXPRESSION)) {
3909 ((JCSwitchExpression) tree).selector = selector;
3910 ((JCSwitchExpression) tree).cases = cases;
3911 } else {
3912 Assert.error();
3913 }
3914 if (enumSwitch) {
3915 result = visitEnumSwitch(tree, selector, cases);
3916 } else if (stringSwitch) {
3917 result = visitStringSwitch(tree, selector, cases);
3918 } else if (boxedSwitch) {
3919 //An switch over boxed primitive. Pattern matching switches are already translated
3920 //by TransPatterns, so all non-primitive types are only boxed primitives:
3921 result = visitBoxedPrimitiveSwitch(tree, selector, cases);
3922 } else {
3923 result = tree;
3924 }
3925 }
3926
3927 public JCTree visitEnumSwitch(JCTree tree, JCExpression selector, List<JCCase> cases) {
3928 TypeSymbol enumSym = selector.type.tsym;
3929 EnumMapping map = mapForEnum(tree.pos(), enumSym);
3930 make_at(tree.pos());
3931 Symbol ordinalMethod = lookupMethod(tree.pos(),
3932 names.ordinal,
3933 selector.type,
3934 List.nil());
3935 JCExpression newSelector;
3936
3937 if (cases.stream().anyMatch(c -> TreeInfo.isNullCaseLabel(c.labels.head))) {
3938 //for enum switches with case null, do:
3939 //switch ($selector != null ? $mapVar[$selector.ordinal()] : -1) {...}
3940 //replacing case null with case -1:
3941 VarSymbol dollar_s = new VarSymbol(FINAL|SYNTHETIC,
3942 names.fromString("s" + variableIndex++ + this.target.syntheticNameChar()),
3943 selector.type,
3944 currentMethodSym);
3945 JCStatement var = make.at(tree.pos()).VarDef(dollar_s, selector).setType(dollar_s.type);
3946 newSelector = map.switchValue(
3947 make.App(make.Select(make.Ident(dollar_s),
3948 ordinalMethod)));
3949 newSelector =
3950 make.LetExpr(List.of(var),
3951 make.Conditional(makeBinary(NE, make.Ident(dollar_s), makeNull()),
3952 newSelector,
3953 makeLit(syms.intType, -1))
3954 .setType(newSelector.type))
3955 .setType(newSelector.type);
3956 } else {
3957 newSelector = map.switchValue(
3958 make.App(make.Select(selector,
3959 ordinalMethod)));
3960 }
3961 ListBuffer<JCCase> newCases = new ListBuffer<>();
3962 for (JCCase c : cases) {
3963 if (c.labels.head.hasTag(CONSTANTCASELABEL)) {
3964 JCExpression pat;
3965 if (TreeInfo.isNullCaseLabel(c.labels.head)) {
3966 pat = makeLit(syms.intType, -1);
3967 } else {
3968 VarSymbol label = (VarSymbol)TreeInfo.symbol(((JCConstantCaseLabel) c.labels.head).expr);
3969 pat = map.caseValue(label);
3970 }
3971 newCases.append(make.Case(JCCase.STATEMENT, List.of(make.ConstantCaseLabel(pat)), null, c.stats, null));
3972 } else {
3973 newCases.append(c);
3974 }
3975 }
3976 JCTree enumSwitch;
3977 if (tree.hasTag(SWITCH)) {
3978 enumSwitch = make.Switch(newSelector, newCases.toList());
3979 } else if (tree.hasTag(SWITCH_EXPRESSION)) {
3980 enumSwitch = make.SwitchExpression(newSelector, newCases.toList());
3981 enumSwitch.setType(tree.type);
3982 } else {
3983 Assert.error();
3984 throw new AssertionError();
3985 }
3986 patchTargets(enumSwitch, tree, enumSwitch);
3987 return enumSwitch;
3988 }
3989
3990 public JCTree visitStringSwitch(JCTree tree, JCExpression selector, List<JCCase> caseList) {
3991 int alternatives = caseList.size();
3992
3993 if (alternatives == 0) { // Strange but legal possibility (only legal for switch statement)
3994 return make.at(tree.pos()).Exec(attr.makeNullCheck(selector));
3995 } else {
3996 /*
3997 * The general approach used is to translate a single
3998 * string switch statement into a series of two chained
3999 * switch statements: the first a synthesized statement
4000 * switching on the argument string's hash value and
4001 * computing a string's position in the list of original
4002 * case labels, if any, followed by a second switch on the
4003 * computed integer value. The second switch has the same
4004 * code structure as the original string switch statement
4005 * except that the string case labels are replaced with
4006 * positional integer constants starting at 0.
4007 *
4008 * The first switch statement can be thought of as an
4009 * inlined map from strings to their position in the case
4010 * label list. An alternate implementation would use an
4011 * actual Map for this purpose, as done for enum switches.
4012 *
4013 * With some additional effort, it would be possible to
4014 * use a single switch statement on the hash code of the
4015 * argument, but care would need to be taken to preserve
4016 * the proper control flow in the presence of hash
4017 * collisions and other complications, such as
4018 * fallthroughs. Switch statements with one or two
4019 * alternatives could also be specially translated into
4020 * if-then statements to omit the computation of the hash
4021 * code.
4022 *
4023 * The generated code assumes that the hashing algorithm
4024 * of String is the same in the compilation environment as
4025 * in the environment the code will run in. The string
4026 * hashing algorithm in the SE JDK has been unchanged
4027 * since at least JDK 1.2. Since the algorithm has been
4028 * specified since that release as well, it is very
4029 * unlikely to be changed in the future.
4030 *
4031 * Different hashing algorithms, such as the length of the
4032 * strings or a perfect hashing algorithm over the
4033 * particular set of case labels, could potentially be
4034 * used instead of String.hashCode.
4035 */
4036
4037 ListBuffer<JCStatement> stmtList = new ListBuffer<>();
4038
4039 // Map from String case labels to their original position in
4040 // the list of case labels.
4041 Map<String, Integer> caseLabelToPosition = new LinkedHashMap<>(alternatives + 1, 1.0f);
4042
4043 // Map of hash codes to the string case labels having that hashCode.
4044 Map<Integer, Set<String>> hashToString = new LinkedHashMap<>(alternatives + 1, 1.0f);
4045
4046 int casePosition = 0;
4047 JCCase nullCase = null;
4048 int nullCaseLabel = -1;
4049
4050 for(JCCase oneCase : caseList) {
4051 if (oneCase.labels.head.hasTag(CONSTANTCASELABEL)) {
4052 if (TreeInfo.isNullCaseLabel(oneCase.labels.head)) {
4053 nullCase = oneCase;
4054 nullCaseLabel = casePosition;
4055 } else {
4056 JCExpression expression = ((JCConstantCaseLabel) oneCase.labels.head).expr;
4057 String labelExpr = (String) expression.type.constValue();
4058 Integer mapping = caseLabelToPosition.put(labelExpr, casePosition);
4059 Assert.checkNull(mapping);
4060 int hashCode = labelExpr.hashCode();
4061
4062 Set<String> stringSet = hashToString.get(hashCode);
4063 if (stringSet == null) {
4064 stringSet = new LinkedHashSet<>(1, 1.0f);
4065 stringSet.add(labelExpr);
4066 hashToString.put(hashCode, stringSet);
4067 } else {
4068 boolean added = stringSet.add(labelExpr);
4069 Assert.check(added);
4070 }
4071 }
4072 }
4073 casePosition++;
4074 }
4075
4076 // Synthesize a switch statement that has the effect of
4077 // mapping from a string to the integer position of that
4078 // string in the list of case labels. This is done by
4079 // switching on the hashCode of the string followed by an
4080 // if-then-else chain comparing the input for equality
4081 // with all the case labels having that hash value.
4082
4083 /*
4084 * s$ = top of stack;
4085 * tmp$ = -1;
4086 * switch($s.hashCode()) {
4087 * case caseLabel.hashCode:
4088 * if (s$.equals("caseLabel_1")
4089 * tmp$ = caseLabelToPosition("caseLabel_1");
4090 * else if (s$.equals("caseLabel_2"))
4091 * tmp$ = caseLabelToPosition("caseLabel_2");
4092 * ...
4093 * break;
4094 * ...
4095 * }
4096 */
4097
4098 VarSymbol dollar_s = new VarSymbol(FINAL|SYNTHETIC,
4099 names.fromString("s" + variableIndex++ + target.syntheticNameChar()),
4100 syms.stringType,
4101 currentMethodSym);
4102 stmtList.append(make.at(tree.pos()).VarDef(dollar_s, selector).setType(dollar_s.type));
4103
4104 VarSymbol dollar_tmp = new VarSymbol(SYNTHETIC,
4105 names.fromString("tmp" + variableIndex++ + target.syntheticNameChar()),
4106 syms.intType,
4107 currentMethodSym);
4108 JCVariableDecl dollar_tmp_def =
4109 (JCVariableDecl)make.VarDef(dollar_tmp, make.Literal(INT, -1)).setType(dollar_tmp.type);
4110 dollar_tmp_def.init.type = dollar_tmp.type = syms.intType;
4111 stmtList.append(dollar_tmp_def);
4112 ListBuffer<JCCase> caseBuffer = new ListBuffer<>();
4113 // hashCode will trigger nullcheck on original switch expression
4114 JCMethodInvocation hashCodeCall = makeCall(make.Ident(dollar_s),
4115 names.hashCode,
4116 List.nil()).setType(syms.intType);
4117 JCSwitch switch1 = make.Switch(hashCodeCall,
4118 caseBuffer.toList());
4119 for(Map.Entry<Integer, Set<String>> entry : hashToString.entrySet()) {
4120 int hashCode = entry.getKey();
4121 Set<String> stringsWithHashCode = entry.getValue();
4122 Assert.check(stringsWithHashCode.size() >= 1);
4123
4124 JCStatement elsepart = null;
4125 for(String caseLabel : stringsWithHashCode ) {
4126 JCMethodInvocation stringEqualsCall = makeCall(make.Ident(dollar_s),
4127 names.equals,
4128 List.of(make.Literal(caseLabel)));
4129 elsepart = make.If(stringEqualsCall,
4130 make.Exec(make.Assign(make.Ident(dollar_tmp),
4131 make.Literal(caseLabelToPosition.get(caseLabel))).
4132 setType(dollar_tmp.type)),
4133 elsepart);
4134 }
4135
4136 ListBuffer<JCStatement> lb = new ListBuffer<>();
4137 JCBreak breakStmt = make.Break(null);
4138 breakStmt.target = switch1;
4139 lb.append(elsepart).append(breakStmt);
4140
4141 caseBuffer.append(make.Case(JCCase.STATEMENT,
4142 List.of(make.ConstantCaseLabel(make.Literal(hashCode))),
4143 null,
4144 lb.toList(),
4145 null));
4146 }
4147
4148 switch1.cases = caseBuffer.toList();
4149
4150 if (nullCase != null) {
4151 stmtList.append(make.If(makeBinary(NE, make.Ident(dollar_s), makeNull()), switch1, make.Exec(make.Assign(make.Ident(dollar_tmp),
4152 make.Literal(nullCaseLabel)).
4153 setType(dollar_tmp.type))).setType(syms.intType));
4154 } else {
4155 stmtList.append(switch1);
4156 }
4157
4158 // Make isomorphic switch tree replacing string labels
4159 // with corresponding integer ones from the label to
4160 // position map.
4161
4162 ListBuffer<JCCase> lb = new ListBuffer<>();
4163 for(JCCase oneCase : caseList ) {
4164 boolean isDefault = !oneCase.labels.head.hasTag(CONSTANTCASELABEL);
4165 JCExpression caseExpr;
4166 if (isDefault)
4167 caseExpr = null;
4168 else if (oneCase == nullCase) {
4169 caseExpr = make.Literal(nullCaseLabel);
4170 } else {
4171 JCExpression expression = ((JCConstantCaseLabel) oneCase.labels.head).expr;
4172 String name = (String) TreeInfo.skipParens(expression)
4173 .type.constValue();
4174 caseExpr = make.Literal(caseLabelToPosition.get(name));
4175 }
4176
4177 lb.append(make.Case(JCCase.STATEMENT, caseExpr == null ? List.of(make.DefaultCaseLabel())
4178 : List.of(make.ConstantCaseLabel(caseExpr)),
4179 null,
4180 oneCase.stats, null));
4181 }
4182
4183 if (tree.hasTag(SWITCH)) {
4184 JCSwitch switch2 = make.Switch(make.Ident(dollar_tmp), lb.toList());
4185 // Rewire up old unlabeled break statements to the
4186 // replacement switch being created.
4187 patchTargets(switch2, tree, switch2);
4188
4189 stmtList.append(switch2);
4190
4191 JCBlock res = make.Block(0L, stmtList.toList());
4192 res.bracePos = TreeInfo.endPos(tree);
4193 return res;
4194 } else {
4195 JCSwitchExpression switch2 = make.SwitchExpression(make.Ident(dollar_tmp), lb.toList());
4196
4197 // Rewire up old unlabeled break statements to the
4198 // replacement switch being created.
4199 patchTargets(switch2, tree, switch2);
4200
4201 switch2.setType(tree.type);
4202
4203 LetExpr res = make.LetExpr(stmtList.toList(), switch2);
4204
4205 res.needsCond = true;
4206 res.setType(tree.type);
4207
4208 return res;
4209 }
4210 }
4211 }
4212
4213 private JCTree visitBoxedPrimitiveSwitch(JCTree tree, JCExpression selector, List<JCCase> cases) {
4214 JCExpression newSelector;
4215
4216 if (cases.stream().anyMatch(c -> TreeInfo.isNullCaseLabel(c.labels.head))) {
4217 //a switch over a boxed primitive, with a null case. Pick two constants that are
4218 //not used by any branch in the case (c1 and c2), close to other constants that are
4219 //used in the switch. Then do:
4220 //switch ($selector != null ? $selector != c1 ? $selector : c2 : c1) {...}
4221 //replacing case null with case c1
4222 Set<Integer> constants = new LinkedHashSet<>();
4223 JCCase nullCase = null;
4224
4225 for (JCCase c : cases) {
4226 if (TreeInfo.isNullCaseLabel(c.labels.head)) {
4227 nullCase = c;
4228 } else if (!c.labels.head.hasTag(DEFAULTCASELABEL)) {
4229 constants.add((int) ((JCConstantCaseLabel) c.labels.head).expr.type.constValue());
4230 }
4231 }
4232
4233 Assert.checkNonNull(nullCase);
4234
4235 int nullValue = constants.isEmpty() ? 0 : constants.iterator().next();
4236
4237 while (constants.contains(nullValue)) nullValue++;
4238
4239 constants.add(nullValue);
4240 nullCase.labels.head = make.ConstantCaseLabel(makeLit(syms.intType, nullValue));
4241
4242 int replacementValue = nullValue;
4243
4244 while (constants.contains(replacementValue)) replacementValue++;
4245
4246 VarSymbol dollar_s = new VarSymbol(FINAL|SYNTHETIC,
4247 names.fromString("s" + variableIndex++ + this.target.syntheticNameChar()),
4248 selector.type,
4249 currentMethodSym);
4250 JCStatement var = make.at(tree.pos()).VarDef(dollar_s, selector).setType(dollar_s.type);
4251 JCExpression nullValueReplacement =
4252 make.Conditional(makeBinary(NE,
4253 unbox(make.Ident(dollar_s), syms.intType),
4254 makeLit(syms.intType, nullValue)),
4255 unbox(make.Ident(dollar_s), syms.intType),
4256 makeLit(syms.intType, replacementValue))
4257 .setType(syms.intType);
4258 JCExpression nullCheck =
4259 make.Conditional(makeBinary(NE, make.Ident(dollar_s), makeNull()),
4260 nullValueReplacement,
4261 makeLit(syms.intType, nullValue))
4262 .setType(syms.intType);
4263 newSelector = make.LetExpr(List.of(var), nullCheck).setType(syms.intType);
4264 } else {
4265 newSelector = unbox(selector, syms.intType);
4266 }
4267
4268 if (tree.hasTag(SWITCH)) {
4269 ((JCSwitch) tree).selector = newSelector;
4270 } else {
4271 ((JCSwitchExpression) tree).selector = newSelector;
4272 }
4273
4274 return tree;
4275 }
4276
4277 @Override
4278 public void visitBreak(JCBreak tree) {
4279 result = tree;
4280 }
4281
4282 @Override
4283 public void visitYield(JCYield tree) {
4284 tree.value = translate(tree.value, tree.target.type);
4285 result = tree;
4286 }
4287
4288 public void visitNewArray(JCNewArray tree) {
4289 tree.elemtype = translate(tree.elemtype);
4290 for (List<JCExpression> t = tree.dims; t.tail != null; t = t.tail)
4291 if (t.head != null) t.head = translate(t.head, syms.intType);
4292 tree.elems = translate(tree.elems, types.elemtype(tree.type));
4293 result = tree;
4294 }
4295
4296 public void visitSelect(JCFieldAccess tree) {
4297 // need to special case-access of the form C.super.x
4298 // these will always need an access method, unless C
4299 // is a default interface subclassed by the current class.
4300 boolean qualifiedSuperAccess =
4301 tree.selected.hasTag(SELECT) &&
4302 TreeInfo.name(tree.selected) == names._super &&
4303 !types.isDirectSuperInterface(((JCFieldAccess)tree.selected).selected.type.tsym, currentClass);
4304 tree.selected = translate(tree.selected);
4305 if (tree.name == names._class && tree.selected.type.isPrimitiveOrVoid()) {
4306 result = classOf(tree.selected);
4307 }
4308 else if (tree.name == names._super &&
4309 types.isDirectSuperInterface(tree.selected.type.tsym, currentClass)) {
4310 //default super call!! Not a classic qualified super call
4311 TypeSymbol supSym = tree.selected.type.tsym;
4312 Assert.checkNonNull(types.asSuper(currentClass.type, supSym));
4313 result = tree;
4314 }
4315 else if (tree.name == names._this || tree.name == names._super) {
4316 result = makeThis(tree.pos(), tree.selected.type.tsym);
4317 }
4318 else
4319 result = access(tree.sym, tree, enclOp, qualifiedSuperAccess);
4320 }
4321
4322 public void visitLetExpr(LetExpr tree) {
4323 tree.defs = translate(tree.defs);
4324 tree.expr = translate(tree.expr, tree.type);
4325 result = tree;
4326 }
4327
4328 // There ought to be nothing to rewrite here;
4329 // we don't generate code.
4330 public void visitAnnotation(JCAnnotation tree) {
4331 result = tree;
4332 }
4333
4334 @Override
4335 public void visitTry(JCTry tree) {
4336 if (tree.resources.nonEmpty()) {
4337 result = makeTwrTry(tree);
4338 return;
4339 }
4340
4341 boolean hasBody = tree.body.getStatements().nonEmpty();
4342 boolean hasCatchers = tree.catchers.nonEmpty();
4343 boolean hasFinally = tree.finalizer != null &&
4344 tree.finalizer.getStatements().nonEmpty();
4345
4346 if (!hasCatchers && !hasFinally) {
4347 result = translate(tree.body);
4348 return;
4349 }
4350
4351 if (!hasBody) {
4352 if (hasFinally) {
4353 result = translate(tree.finalizer);
4354 } else {
4355 result = translate(tree.body);
4356 }
4357 return;
4358 }
4359
4360 // no optimizations possible
4361 super.visitTry(tree);
4362 }
4363
4364 /* ************************************************************************
4365 * main method
4366 *************************************************************************/
4367
4368 /** Translate a toplevel class and return a list consisting of
4369 * the translated class and translated versions of all inner classes.
4370 * @param env The attribution environment current at the class definition.
4371 * We need this for resolving some additional symbols.
4372 * @param cdef The tree representing the class definition.
4373 */
4374 public List<JCTree> translateTopLevelClass(Env<AttrContext> env, JCTree cdef, TreeMaker make) {
4375 ListBuffer<JCTree> translated = null;
4376 try {
4377 attrEnv = env;
4378 this.make = make;
4379 currentClass = null;
4380 currentRestype = null;
4381 currentMethodDef = null;
4382 outermostClassDef = (cdef.hasTag(CLASSDEF)) ? (JCClassDecl)cdef : null;
4383 outermostMemberDef = null;
4384 this.translated = new ListBuffer<>();
4385 classdefs = new HashMap<>();
4386 actualSymbols = new HashMap<>();
4387 freevarCache = new HashMap<>();
4388 proxies = new HashMap<>();
4389 twrVars = WriteableScope.create(syms.noSymbol);
4390 outerThisStack = List.nil();
4391 accessNums = new HashMap<>();
4392 accessSyms = new HashMap<>();
4393 accessConstrs = new HashMap<>();
4394 accessConstrTags = List.nil();
4395 accessed = new ListBuffer<>();
4396 translate(cdef, (JCExpression)null);
4397 for (List<Symbol> l = accessed.toList(); l.nonEmpty(); l = l.tail)
4398 makeAccessible(l.head);
4399 for (EnumMapping map : enumSwitchMap.values())
4400 map.translate();
4401 checkConflicts(this.translated.toList());
4402 checkAccessConstructorTags();
4403 translated = this.translated;
4404 } finally {
4405 // note that recursive invocations of this method fail hard
4406 attrEnv = null;
4407 this.make = null;
4408 currentClass = null;
4409 currentRestype = null;
4410 currentMethodDef = null;
4411 outermostClassDef = null;
4412 outermostMemberDef = null;
4413 this.translated = null;
4414 classdefs = null;
4415 actualSymbols = null;
4416 freevarCache = null;
4417 proxies = null;
4418 outerThisStack = null;
4419 accessNums = null;
4420 accessSyms = null;
4421 accessConstrs = null;
4422 accessConstrTags = null;
4423 accessed = null;
4424 enumSwitchMap.clear();
4425 assertionsDisabledClassCache = null;
4426 }
4427 return translated.toList();
4428 }
4429
4430 // needed for the lambda deserialization method, which is expressed as a big switch on strings
4431 public JCMethodDecl translateMethod(Env<AttrContext> env, JCMethodDecl methodDecl, TreeMaker make) {
4432 try {
4433 this.attrEnv = env;
4434 this.make = make;
4435 this.currentClass = methodDecl.sym.enclClass();
4436 proxies = new HashMap<>();
4437 return translate(methodDecl);
4438 } finally {
4439 this.attrEnv = null;
4440 this.make = null;
4441 this.currentClass = null;
4442 // the two fields below are set when visiting the method
4443 this.currentMethodSym = null;
4444 this.currentMethodDef = null;
4445 this.proxies = null;
4446 }
4447 }
4448 }