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src/share/classes/com/sun/tools/javac/code/Types.java@ca5783d9a597
src/share/classes/com/sun/tools/javac/code/Types.java
Mon, 16 Oct 2017 16:07:48 +0800
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- aoqi
- date
- Mon, 16 Oct 2017 16:07:48 +0800
- changeset 2893
- ca5783d9a597
- parent 2813
- d94fe2d29b1e
- parent 2702
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1 /*
2 * Copyright (c) 2003, 2014, 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 */
26 package com.sun.tools.javac.code;
28 import java.lang.ref.SoftReference;
29 import java.util.HashSet;
30 import java.util.HashMap;
31 import java.util.Locale;
32 import java.util.Map;
33 import java.util.Set;
34 import java.util.WeakHashMap;
36 import javax.tools.JavaFileObject;
38 import com.sun.tools.javac.code.Attribute.RetentionPolicy;
39 import com.sun.tools.javac.code.Lint.LintCategory;
40 import com.sun.tools.javac.code.Type.UndetVar.InferenceBound;
41 import com.sun.tools.javac.comp.AttrContext;
42 import com.sun.tools.javac.comp.Check;
43 import com.sun.tools.javac.comp.Enter;
44 import com.sun.tools.javac.comp.Env;
45 import com.sun.tools.javac.jvm.ClassReader;
46 import com.sun.tools.javac.tree.JCTree;
47 import com.sun.tools.javac.util.*;
48 import static com.sun.tools.javac.code.BoundKind.*;
49 import static com.sun.tools.javac.code.Flags.*;
50 import static com.sun.tools.javac.code.Kinds.MTH;
51 import static com.sun.tools.javac.code.Scope.*;
52 import static com.sun.tools.javac.code.Symbol.*;
53 import static com.sun.tools.javac.code.Type.*;
54 import static com.sun.tools.javac.code.TypeTag.*;
55 import static com.sun.tools.javac.jvm.ClassFile.externalize;
57 /**
58 * Utility class containing various operations on types.
59 *
60 * <p>Unless other names are more illustrative, the following naming
61 * conventions should be observed in this file:
62 *
63 * <dl>
64 * <dt>t</dt>
65 * <dd>If the first argument to an operation is a type, it should be named t.</dd>
66 * <dt>s</dt>
67 * <dd>Similarly, if the second argument to an operation is a type, it should be named s.</dd>
68 * <dt>ts</dt>
69 * <dd>If an operations takes a list of types, the first should be named ts.</dd>
70 * <dt>ss</dt>
71 * <dd>A second list of types should be named ss.</dd>
72 * </dl>
73 *
74 * <p><b>This is NOT part of any supported API.
75 * If you write code that depends on this, you do so at your own risk.
76 * This code and its internal interfaces are subject to change or
77 * deletion without notice.</b>
78 */
79 public class Types {
80 protected static final Context.Key<Types> typesKey =
81 new Context.Key<Types>();
83 final Symtab syms;
84 final JavacMessages messages;
85 final Names names;
86 final boolean allowBoxing;
87 final boolean allowCovariantReturns;
88 final boolean allowObjectToPrimitiveCast;
89 final boolean allowDefaultMethods;
90 final ClassReader reader;
91 final Check chk;
92 final Enter enter;
93 JCDiagnostic.Factory diags;
94 List<Warner> warnStack = List.nil();
95 final Name capturedName;
96 private final FunctionDescriptorLookupError functionDescriptorLookupError;
98 public final Warner noWarnings;
100 // <editor-fold defaultstate="collapsed" desc="Instantiating">
101 public static Types instance(Context context) {
102 Types instance = context.get(typesKey);
103 if (instance == null)
104 instance = new Types(context);
105 return instance;
106 }
108 protected Types(Context context) {
109 context.put(typesKey, this);
110 syms = Symtab.instance(context);
111 names = Names.instance(context);
112 Source source = Source.instance(context);
113 allowBoxing = source.allowBoxing();
114 allowCovariantReturns = source.allowCovariantReturns();
115 allowObjectToPrimitiveCast = source.allowObjectToPrimitiveCast();
116 allowDefaultMethods = source.allowDefaultMethods();
117 reader = ClassReader.instance(context);
118 chk = Check.instance(context);
119 enter = Enter.instance(context);
120 capturedName = names.fromString("<captured wildcard>");
121 messages = JavacMessages.instance(context);
122 diags = JCDiagnostic.Factory.instance(context);
123 functionDescriptorLookupError = new FunctionDescriptorLookupError();
124 noWarnings = new Warner(null);
125 }
126 // </editor-fold>
128 // <editor-fold defaultstate="collapsed" desc="bounds">
129 /**
130 * Get a wildcard's upper bound, returning non-wildcards unchanged.
131 * @param t a type argument, either a wildcard or a type
132 */
133 public Type wildUpperBound(Type t) {
134 if (t.hasTag(WILDCARD)) {
135 WildcardType w = (WildcardType) t.unannotatedType();
136 if (w.isSuperBound())
137 return w.bound == null ? syms.objectType : w.bound.bound;
138 else
139 return wildUpperBound(w.type);
140 }
141 else return t.unannotatedType();
142 }
144 /**
145 * Get a capture variable's upper bound, returning other types unchanged.
146 * @param t a type
147 */
148 public Type cvarUpperBound(Type t) {
149 if (t.hasTag(TYPEVAR)) {
150 TypeVar v = (TypeVar) t.unannotatedType();
151 return v.isCaptured() ? cvarUpperBound(v.bound) : v;
152 }
153 else return t.unannotatedType();
154 }
156 /**
157 * Get a wildcard's lower bound, returning non-wildcards unchanged.
158 * @param t a type argument, either a wildcard or a type
159 */
160 public Type wildLowerBound(Type t) {
161 if (t.hasTag(WILDCARD)) {
162 WildcardType w = (WildcardType) t.unannotatedType();
163 return w.isExtendsBound() ? syms.botType : wildLowerBound(w.type);
164 }
165 else return t.unannotatedType();
166 }
168 /**
169 * Get a capture variable's lower bound, returning other types unchanged.
170 * @param t a type
171 */
172 public Type cvarLowerBound(Type t) {
173 if (t.hasTag(TYPEVAR)) {
174 TypeVar v = (TypeVar) t.unannotatedType();
175 return v.isCaptured() ? cvarLowerBound(v.getLowerBound()) : v;
176 }
177 else return t.unannotatedType();
178 }
179 // </editor-fold>
181 // <editor-fold defaultstate="collapsed" desc="isUnbounded">
182 /**
183 * Checks that all the arguments to a class are unbounded
184 * wildcards or something else that doesn't make any restrictions
185 * on the arguments. If a class isUnbounded, a raw super- or
186 * subclass can be cast to it without a warning.
187 * @param t a type
188 * @return true iff the given type is unbounded or raw
189 */
190 public boolean isUnbounded(Type t) {
191 return isUnbounded.visit(t);
192 }
193 // where
194 private final UnaryVisitor<Boolean> isUnbounded = new UnaryVisitor<Boolean>() {
196 public Boolean visitType(Type t, Void ignored) {
197 return true;
198 }
200 @Override
201 public Boolean visitClassType(ClassType t, Void ignored) {
202 List<Type> parms = t.tsym.type.allparams();
203 List<Type> args = t.allparams();
204 while (parms.nonEmpty()) {
205 WildcardType unb = new WildcardType(syms.objectType,
206 BoundKind.UNBOUND,
207 syms.boundClass,
208 (TypeVar)parms.head.unannotatedType());
209 if (!containsType(args.head, unb))
210 return false;
211 parms = parms.tail;
212 args = args.tail;
213 }
214 return true;
215 }
216 };
217 // </editor-fold>
219 // <editor-fold defaultstate="collapsed" desc="asSub">
220 /**
221 * Return the least specific subtype of t that starts with symbol
222 * sym. If none exists, return null. The least specific subtype
223 * is determined as follows:
224 *
225 * <p>If there is exactly one parameterized instance of sym that is a
226 * subtype of t, that parameterized instance is returned.<br>
227 * Otherwise, if the plain type or raw type `sym' is a subtype of
228 * type t, the type `sym' itself is returned. Otherwise, null is
229 * returned.
230 */
231 public Type asSub(Type t, Symbol sym) {
232 return asSub.visit(t, sym);
233 }
234 // where
235 private final SimpleVisitor<Type,Symbol> asSub = new SimpleVisitor<Type,Symbol>() {
237 public Type visitType(Type t, Symbol sym) {
238 return null;
239 }
241 @Override
242 public Type visitClassType(ClassType t, Symbol sym) {
243 if (t.tsym == sym)
244 return t;
245 Type base = asSuper(sym.type, t.tsym);
246 if (base == null)
247 return null;
248 ListBuffer<Type> from = new ListBuffer<Type>();
249 ListBuffer<Type> to = new ListBuffer<Type>();
250 try {
251 adapt(base, t, from, to);
252 } catch (AdaptFailure ex) {
253 return null;
254 }
255 Type res = subst(sym.type, from.toList(), to.toList());
256 if (!isSubtype(res, t))
257 return null;
258 ListBuffer<Type> openVars = new ListBuffer<Type>();
259 for (List<Type> l = sym.type.allparams();
260 l.nonEmpty(); l = l.tail)
261 if (res.contains(l.head) && !t.contains(l.head))
262 openVars.append(l.head);
263 if (openVars.nonEmpty()) {
264 if (t.isRaw()) {
265 // The subtype of a raw type is raw
266 res = erasure(res);
267 } else {
268 // Unbound type arguments default to ?
269 List<Type> opens = openVars.toList();
270 ListBuffer<Type> qs = new ListBuffer<Type>();
271 for (List<Type> iter = opens; iter.nonEmpty(); iter = iter.tail) {
272 qs.append(new WildcardType(syms.objectType, BoundKind.UNBOUND, syms.boundClass, (TypeVar) iter.head.unannotatedType()));
273 }
274 res = subst(res, opens, qs.toList());
275 }
276 }
277 return res;
278 }
280 @Override
281 public Type visitErrorType(ErrorType t, Symbol sym) {
282 return t;
283 }
284 };
285 // </editor-fold>
287 // <editor-fold defaultstate="collapsed" desc="isConvertible">
288 /**
289 * Is t a subtype of or convertible via boxing/unboxing
290 * conversion to s?
291 */
292 public boolean isConvertible(Type t, Type s, Warner warn) {
293 if (t.hasTag(ERROR)) {
294 return true;
295 }
296 boolean tPrimitive = t.isPrimitive();
297 boolean sPrimitive = s.isPrimitive();
298 if (tPrimitive == sPrimitive) {
299 return isSubtypeUnchecked(t, s, warn);
300 }
301 if (!allowBoxing) return false;
302 return tPrimitive
303 ? isSubtype(boxedClass(t).type, s)
304 : isSubtype(unboxedType(t), s);
305 }
307 /**
308 * Is t a subtype of or convertible via boxing/unboxing
309 * conversions to s?
310 */
311 public boolean isConvertible(Type t, Type s) {
312 return isConvertible(t, s, noWarnings);
313 }
314 // </editor-fold>
316 // <editor-fold defaultstate="collapsed" desc="findSam">
318 /**
319 * Exception used to report a function descriptor lookup failure. The exception
320 * wraps a diagnostic that can be used to generate more details error
321 * messages.
322 */
323 public static class FunctionDescriptorLookupError extends RuntimeException {
324 private static final long serialVersionUID = 0;
326 JCDiagnostic diagnostic;
328 FunctionDescriptorLookupError() {
329 this.diagnostic = null;
330 }
332 FunctionDescriptorLookupError setMessage(JCDiagnostic diag) {
333 this.diagnostic = diag;
334 return this;
335 }
337 public JCDiagnostic getDiagnostic() {
338 return diagnostic;
339 }
340 }
342 /**
343 * A cache that keeps track of function descriptors associated with given
344 * functional interfaces.
345 */
346 class DescriptorCache {
348 private WeakHashMap<TypeSymbol, Entry> _map = new WeakHashMap<TypeSymbol, Entry>();
350 class FunctionDescriptor {
351 Symbol descSym;
353 FunctionDescriptor(Symbol descSym) {
354 this.descSym = descSym;
355 }
357 public Symbol getSymbol() {
358 return descSym;
359 }
361 public Type getType(Type site) {
362 site = removeWildcards(site);
363 if (!chk.checkValidGenericType(site)) {
364 //if the inferred functional interface type is not well-formed,
365 //or if it's not a subtype of the original target, issue an error
366 throw failure(diags.fragment("no.suitable.functional.intf.inst", site));
367 }
368 return memberType(site, descSym);
369 }
370 }
372 class Entry {
373 final FunctionDescriptor cachedDescRes;
374 final int prevMark;
376 public Entry(FunctionDescriptor cachedDescRes,
377 int prevMark) {
378 this.cachedDescRes = cachedDescRes;
379 this.prevMark = prevMark;
380 }
382 boolean matches(int mark) {
383 return this.prevMark == mark;
384 }
385 }
387 FunctionDescriptor get(TypeSymbol origin) throws FunctionDescriptorLookupError {
388 Entry e = _map.get(origin);
389 CompoundScope members = membersClosure(origin.type, false);
390 if (e == null ||
391 !e.matches(members.getMark())) {
392 FunctionDescriptor descRes = findDescriptorInternal(origin, members);
393 _map.put(origin, new Entry(descRes, members.getMark()));
394 return descRes;
395 }
396 else {
397 return e.cachedDescRes;
398 }
399 }
401 /**
402 * Compute the function descriptor associated with a given functional interface
403 */
404 public FunctionDescriptor findDescriptorInternal(TypeSymbol origin,
405 CompoundScope membersCache) throws FunctionDescriptorLookupError {
406 if (!origin.isInterface() || (origin.flags() & ANNOTATION) != 0) {
407 //t must be an interface
408 throw failure("not.a.functional.intf", origin);
409 }
411 final ListBuffer<Symbol> abstracts = new ListBuffer<>();
412 for (Symbol sym : membersCache.getElements(new DescriptorFilter(origin))) {
413 Type mtype = memberType(origin.type, sym);
414 if (abstracts.isEmpty() ||
415 (sym.name == abstracts.first().name &&
416 overrideEquivalent(mtype, memberType(origin.type, abstracts.first())))) {
417 abstracts.append(sym);
418 } else {
419 //the target method(s) should be the only abstract members of t
420 throw failure("not.a.functional.intf.1", origin,
421 diags.fragment("incompatible.abstracts", Kinds.kindName(origin), origin));
422 }
423 }
424 if (abstracts.isEmpty()) {
425 //t must define a suitable non-generic method
426 throw failure("not.a.functional.intf.1", origin,
427 diags.fragment("no.abstracts", Kinds.kindName(origin), origin));
428 } else if (abstracts.size() == 1) {
429 return new FunctionDescriptor(abstracts.first());
430 } else { // size > 1
431 FunctionDescriptor descRes = mergeDescriptors(origin, abstracts.toList());
432 if (descRes == null) {
433 //we can get here if the functional interface is ill-formed
434 ListBuffer<JCDiagnostic> descriptors = new ListBuffer<>();
435 for (Symbol desc : abstracts) {
436 String key = desc.type.getThrownTypes().nonEmpty() ?
437 "descriptor.throws" : "descriptor";
438 descriptors.append(diags.fragment(key, desc.name,
439 desc.type.getParameterTypes(),
440 desc.type.getReturnType(),
441 desc.type.getThrownTypes()));
442 }
443 JCDiagnostic.MultilineDiagnostic incompatibleDescriptors =
444 new JCDiagnostic.MultilineDiagnostic(diags.fragment("incompatible.descs.in.functional.intf",
445 Kinds.kindName(origin), origin), descriptors.toList());
446 throw failure(incompatibleDescriptors);
447 }
448 return descRes;
449 }
450 }
452 /**
453 * Compute a synthetic type for the target descriptor given a list
454 * of override-equivalent methods in the functional interface type.
455 * The resulting method type is a method type that is override-equivalent
456 * and return-type substitutable with each method in the original list.
457 */
458 private FunctionDescriptor mergeDescriptors(TypeSymbol origin, List<Symbol> methodSyms) {
459 //pick argument types - simply take the signature that is a
460 //subsignature of all other signatures in the list (as per JLS 8.4.2)
461 List<Symbol> mostSpecific = List.nil();
462 outer: for (Symbol msym1 : methodSyms) {
463 Type mt1 = memberType(origin.type, msym1);
464 for (Symbol msym2 : methodSyms) {
465 Type mt2 = memberType(origin.type, msym2);
466 if (!isSubSignature(mt1, mt2)) {
467 continue outer;
468 }
469 }
470 mostSpecific = mostSpecific.prepend(msym1);
471 }
472 if (mostSpecific.isEmpty()) {
473 return null;
474 }
477 //pick return types - this is done in two phases: (i) first, the most
478 //specific return type is chosen using strict subtyping; if this fails,
479 //a second attempt is made using return type substitutability (see JLS 8.4.5)
480 boolean phase2 = false;
481 Symbol bestSoFar = null;
482 while (bestSoFar == null) {
483 outer: for (Symbol msym1 : mostSpecific) {
484 Type mt1 = memberType(origin.type, msym1);
485 for (Symbol msym2 : methodSyms) {
486 Type mt2 = memberType(origin.type, msym2);
487 if (phase2 ?
488 !returnTypeSubstitutable(mt1, mt2) :
489 !isSubtypeInternal(mt1.getReturnType(), mt2.getReturnType())) {
490 continue outer;
491 }
492 }
493 bestSoFar = msym1;
494 }
495 if (phase2) {
496 break;
497 } else {
498 phase2 = true;
499 }
500 }
501 if (bestSoFar == null) return null;
503 //merge thrown types - form the intersection of all the thrown types in
504 //all the signatures in the list
505 boolean toErase = !bestSoFar.type.hasTag(FORALL);
506 List<Type> thrown = null;
507 Type mt1 = memberType(origin.type, bestSoFar);
508 for (Symbol msym2 : methodSyms) {
509 Type mt2 = memberType(origin.type, msym2);
510 List<Type> thrown_mt2 = mt2.getThrownTypes();
511 if (toErase) {
512 thrown_mt2 = erasure(thrown_mt2);
513 } else {
514 /* If bestSoFar is generic then all the methods are generic.
515 * The opposite is not true: a non generic method can override
516 * a generic method (raw override) so it's safe to cast mt1 and
517 * mt2 to ForAll.
518 */
519 ForAll fa1 = (ForAll)mt1;
520 ForAll fa2 = (ForAll)mt2;
521 thrown_mt2 = subst(thrown_mt2, fa2.tvars, fa1.tvars);
522 }
523 thrown = (thrown == null) ?
524 thrown_mt2 :
525 chk.intersect(thrown_mt2, thrown);
526 }
528 final List<Type> thrown1 = thrown;
529 return new FunctionDescriptor(bestSoFar) {
530 @Override
531 public Type getType(Type origin) {
532 Type mt = memberType(origin, getSymbol());
533 return createMethodTypeWithThrown(mt, thrown1);
534 }
535 };
536 }
538 boolean isSubtypeInternal(Type s, Type t) {
539 return (s.isPrimitive() && t.isPrimitive()) ?
540 isSameType(t, s) :
541 isSubtype(s, t);
542 }
544 FunctionDescriptorLookupError failure(String msg, Object... args) {
545 return failure(diags.fragment(msg, args));
546 }
548 FunctionDescriptorLookupError failure(JCDiagnostic diag) {
549 return functionDescriptorLookupError.setMessage(diag);
550 }
551 }
553 private DescriptorCache descCache = new DescriptorCache();
555 /**
556 * Find the method descriptor associated to this class symbol - if the
557 * symbol 'origin' is not a functional interface, an exception is thrown.
558 */
559 public Symbol findDescriptorSymbol(TypeSymbol origin) throws FunctionDescriptorLookupError {
560 return descCache.get(origin).getSymbol();
561 }
563 /**
564 * Find the type of the method descriptor associated to this class symbol -
565 * if the symbol 'origin' is not a functional interface, an exception is thrown.
566 */
567 public Type findDescriptorType(Type origin) throws FunctionDescriptorLookupError {
568 return descCache.get(origin.tsym).getType(origin);
569 }
571 /**
572 * Is given type a functional interface?
573 */
574 public boolean isFunctionalInterface(TypeSymbol tsym) {
575 try {
576 findDescriptorSymbol(tsym);
577 return true;
578 } catch (FunctionDescriptorLookupError ex) {
579 return false;
580 }
581 }
583 public boolean isFunctionalInterface(Type site) {
584 try {
585 findDescriptorType(site);
586 return true;
587 } catch (FunctionDescriptorLookupError ex) {
588 return false;
589 }
590 }
592 public Type removeWildcards(Type site) {
593 Type capturedSite = capture(site);
594 if (capturedSite != site) {
595 Type formalInterface = site.tsym.type;
596 ListBuffer<Type> typeargs = new ListBuffer<>();
597 List<Type> actualTypeargs = site.getTypeArguments();
598 List<Type> capturedTypeargs = capturedSite.getTypeArguments();
599 //simply replace the wildcards with its bound
600 for (Type t : formalInterface.getTypeArguments()) {
601 if (actualTypeargs.head.hasTag(WILDCARD)) {
602 WildcardType wt = (WildcardType)actualTypeargs.head.unannotatedType();
603 Type bound;
604 switch (wt.kind) {
605 case EXTENDS:
606 case UNBOUND:
607 CapturedType capVar = (CapturedType)capturedTypeargs.head.unannotatedType();
608 //use declared bound if it doesn't depend on formal type-args
609 bound = capVar.bound.containsAny(capturedSite.getTypeArguments()) ?
610 wt.type : capVar.bound;
611 break;
612 default:
613 bound = wt.type;
614 }
615 typeargs.append(bound);
616 } else {
617 typeargs.append(actualTypeargs.head);
618 }
619 actualTypeargs = actualTypeargs.tail;
620 capturedTypeargs = capturedTypeargs.tail;
621 }
622 return subst(formalInterface, formalInterface.getTypeArguments(), typeargs.toList());
623 } else {
624 return site;
625 }
626 }
628 /**
629 * Create a symbol for a class that implements a given functional interface
630 * and overrides its functional descriptor. This routine is used for two
631 * main purposes: (i) checking well-formedness of a functional interface;
632 * (ii) perform functional interface bridge calculation.
633 */
634 public ClassSymbol makeFunctionalInterfaceClass(Env<AttrContext> env, Name name, List<Type> targets, long cflags) {
635 if (targets.isEmpty()) {
636 return null;
637 }
638 Symbol descSym = findDescriptorSymbol(targets.head.tsym);
639 Type descType = findDescriptorType(targets.head);
640 ClassSymbol csym = new ClassSymbol(cflags, name, env.enclClass.sym.outermostClass());
641 csym.completer = null;
642 csym.members_field = new Scope(csym);
643 MethodSymbol instDescSym = new MethodSymbol(descSym.flags(), descSym.name, descType, csym);
644 csym.members_field.enter(instDescSym);
645 Type.ClassType ctype = new Type.ClassType(Type.noType, List.<Type>nil(), csym);
646 ctype.supertype_field = syms.objectType;
647 ctype.interfaces_field = targets;
648 csym.type = ctype;
649 csym.sourcefile = ((ClassSymbol)csym.owner).sourcefile;
650 return csym;
651 }
653 /**
654 * Find the minimal set of methods that are overridden by the functional
655 * descriptor in 'origin'. All returned methods are assumed to have different
656 * erased signatures.
657 */
658 public List<Symbol> functionalInterfaceBridges(TypeSymbol origin) {
659 Assert.check(isFunctionalInterface(origin));
660 Symbol descSym = findDescriptorSymbol(origin);
661 CompoundScope members = membersClosure(origin.type, false);
662 ListBuffer<Symbol> overridden = new ListBuffer<>();
663 outer: for (Symbol m2 : members.getElementsByName(descSym.name, bridgeFilter)) {
664 if (m2 == descSym) continue;
665 else if (descSym.overrides(m2, origin, Types.this, false)) {
666 for (Symbol m3 : overridden) {
667 if (isSameType(m3.erasure(Types.this), m2.erasure(Types.this)) ||
668 (m3.overrides(m2, origin, Types.this, false) &&
669 (pendingBridges((ClassSymbol)origin, m3.enclClass()) ||
670 (((MethodSymbol)m2).binaryImplementation((ClassSymbol)m3.owner, Types.this) != null)))) {
671 continue outer;
672 }
673 }
674 overridden.add(m2);
675 }
676 }
677 return overridden.toList();
678 }
679 //where
680 private Filter<Symbol> bridgeFilter = new Filter<Symbol>() {
681 public boolean accepts(Symbol t) {
682 return t.kind == Kinds.MTH &&
683 t.name != names.init &&
684 t.name != names.clinit &&
685 (t.flags() & SYNTHETIC) == 0;
686 }
687 };
688 private boolean pendingBridges(ClassSymbol origin, TypeSymbol s) {
689 //a symbol will be completed from a classfile if (a) symbol has
690 //an associated file object with CLASS kind and (b) the symbol has
691 //not been entered
692 if (origin.classfile != null &&
693 origin.classfile.getKind() == JavaFileObject.Kind.CLASS &&
694 enter.getEnv(origin) == null) {
695 return false;
696 }
697 if (origin == s) {
698 return true;
699 }
700 for (Type t : interfaces(origin.type)) {
701 if (pendingBridges((ClassSymbol)t.tsym, s)) {
702 return true;
703 }
704 }
705 return false;
706 }
707 // </editor-fold>
709 /**
710 * Scope filter used to skip methods that should be ignored (such as methods
711 * overridden by j.l.Object) during function interface conversion interface check
712 */
713 class DescriptorFilter implements Filter<Symbol> {
715 TypeSymbol origin;
717 DescriptorFilter(TypeSymbol origin) {
718 this.origin = origin;
719 }
721 @Override
722 public boolean accepts(Symbol sym) {
723 return sym.kind == Kinds.MTH &&
724 (sym.flags() & (ABSTRACT | DEFAULT)) == ABSTRACT &&
725 !overridesObjectMethod(origin, sym) &&
726 (interfaceCandidates(origin.type, (MethodSymbol)sym).head.flags() & DEFAULT) == 0;
727 }
728 };
730 // <editor-fold defaultstate="collapsed" desc="isSubtype">
731 /**
732 * Is t an unchecked subtype of s?
733 */
734 public boolean isSubtypeUnchecked(Type t, Type s) {
735 return isSubtypeUnchecked(t, s, noWarnings);
736 }
737 /**
738 * Is t an unchecked subtype of s?
739 */
740 public boolean isSubtypeUnchecked(Type t, Type s, Warner warn) {
741 boolean result = isSubtypeUncheckedInternal(t, s, warn);
742 if (result) {
743 checkUnsafeVarargsConversion(t, s, warn);
744 }
745 return result;
746 }
747 //where
748 private boolean isSubtypeUncheckedInternal(Type t, Type s, Warner warn) {
749 if (t.hasTag(ARRAY) && s.hasTag(ARRAY)) {
750 t = t.unannotatedType();
751 s = s.unannotatedType();
752 if (((ArrayType)t).elemtype.isPrimitive()) {
753 return isSameType(elemtype(t), elemtype(s));
754 } else {
755 return isSubtypeUnchecked(elemtype(t), elemtype(s), warn);
756 }
757 } else if (isSubtype(t, s)) {
758 return true;
759 } else if (t.hasTag(TYPEVAR)) {
760 return isSubtypeUnchecked(t.getUpperBound(), s, warn);
761 } else if (!s.isRaw()) {
762 Type t2 = asSuper(t, s.tsym);
763 if (t2 != null && t2.isRaw()) {
764 if (isReifiable(s)) {
765 warn.silentWarn(LintCategory.UNCHECKED);
766 } else {
767 warn.warn(LintCategory.UNCHECKED);
768 }
769 return true;
770 }
771 }
772 return false;
773 }
775 private void checkUnsafeVarargsConversion(Type t, Type s, Warner warn) {
776 if (!t.hasTag(ARRAY) || isReifiable(t)) {
777 return;
778 }
779 t = t.unannotatedType();
780 s = s.unannotatedType();
781 ArrayType from = (ArrayType)t;
782 boolean shouldWarn = false;
783 switch (s.getTag()) {
784 case ARRAY:
785 ArrayType to = (ArrayType)s;
786 shouldWarn = from.isVarargs() &&
787 !to.isVarargs() &&
788 !isReifiable(from);
789 break;
790 case CLASS:
791 shouldWarn = from.isVarargs();
792 break;
793 }
794 if (shouldWarn) {
795 warn.warn(LintCategory.VARARGS);
796 }
797 }
799 /**
800 * Is t a subtype of s?<br>
801 * (not defined for Method and ForAll types)
802 */
803 final public boolean isSubtype(Type t, Type s) {
804 return isSubtype(t, s, true);
805 }
806 final public boolean isSubtypeNoCapture(Type t, Type s) {
807 return isSubtype(t, s, false);
808 }
809 public boolean isSubtype(Type t, Type s, boolean capture) {
810 if (t == s)
811 return true;
813 t = t.unannotatedType();
814 s = s.unannotatedType();
816 if (t == s)
817 return true;
819 if (s.isPartial())
820 return isSuperType(s, t);
822 if (s.isCompound()) {
823 for (Type s2 : interfaces(s).prepend(supertype(s))) {
824 if (!isSubtype(t, s2, capture))
825 return false;
826 }
827 return true;
828 }
830 // Generally, if 's' is a type variable, recur on lower bound; but
831 // for inference variables and intersections, we need to keep 's'
832 // (see JLS 4.10.2 for intersections and 18.2.3 for inference vars)
833 if (!t.hasTag(UNDETVAR) && !t.isCompound()) {
834 // TODO: JDK-8039198, bounds checking sometimes passes in a wildcard as s
835 Type lower = cvarLowerBound(wildLowerBound(s));
836 if (s != lower)
837 return isSubtype(capture ? capture(t) : t, lower, false);
838 }
840 return isSubtype.visit(capture ? capture(t) : t, s);
841 }
842 // where
843 private TypeRelation isSubtype = new TypeRelation()
844 {
845 @Override
846 public Boolean visitType(Type t, Type s) {
847 switch (t.getTag()) {
848 case BYTE:
849 return (!s.hasTag(CHAR) && t.getTag().isSubRangeOf(s.getTag()));
850 case CHAR:
851 return (!s.hasTag(SHORT) && t.getTag().isSubRangeOf(s.getTag()));
852 case SHORT: case INT: case LONG:
853 case FLOAT: case DOUBLE:
854 return t.getTag().isSubRangeOf(s.getTag());
855 case BOOLEAN: case VOID:
856 return t.hasTag(s.getTag());
857 case TYPEVAR:
858 return isSubtypeNoCapture(t.getUpperBound(), s);
859 case BOT:
860 return
861 s.hasTag(BOT) || s.hasTag(CLASS) ||
862 s.hasTag(ARRAY) || s.hasTag(TYPEVAR);
863 case WILDCARD: //we shouldn't be here - avoids crash (see 7034495)
864 case NONE:
865 return false;
866 default:
867 throw new AssertionError("isSubtype " + t.getTag());
868 }
869 }
871 private Set<TypePair> cache = new HashSet<TypePair>();
873 private boolean containsTypeRecursive(Type t, Type s) {
874 TypePair pair = new TypePair(t, s);
875 if (cache.add(pair)) {
876 try {
877 return containsType(t.getTypeArguments(),
878 s.getTypeArguments());
879 } finally {
880 cache.remove(pair);
881 }
882 } else {
883 return containsType(t.getTypeArguments(),
884 rewriteSupers(s).getTypeArguments());
885 }
886 }
888 private Type rewriteSupers(Type t) {
889 if (!t.isParameterized())
890 return t;
891 ListBuffer<Type> from = new ListBuffer<>();
892 ListBuffer<Type> to = new ListBuffer<>();
893 adaptSelf(t, from, to);
894 if (from.isEmpty())
895 return t;
896 ListBuffer<Type> rewrite = new ListBuffer<>();
897 boolean changed = false;
898 for (Type orig : to.toList()) {
899 Type s = rewriteSupers(orig);
900 if (s.isSuperBound() && !s.isExtendsBound()) {
901 s = new WildcardType(syms.objectType,
902 BoundKind.UNBOUND,
903 syms.boundClass);
904 changed = true;
905 } else if (s != orig) {
906 s = new WildcardType(wildUpperBound(s),
907 BoundKind.EXTENDS,
908 syms.boundClass);
909 changed = true;
910 }
911 rewrite.append(s);
912 }
913 if (changed)
914 return subst(t.tsym.type, from.toList(), rewrite.toList());
915 else
916 return t;
917 }
919 @Override
920 public Boolean visitClassType(ClassType t, Type s) {
921 Type sup = asSuper(t, s.tsym);
922 if (sup == null) return false;
923 // If t is an intersection, sup might not be a class type
924 if (!sup.hasTag(CLASS)) return isSubtypeNoCapture(sup, s);
925 return sup.tsym == s.tsym
926 // Check type variable containment
927 && (!s.isParameterized() || containsTypeRecursive(s, sup))
928 && isSubtypeNoCapture(sup.getEnclosingType(),
929 s.getEnclosingType());
930 }
932 @Override
933 public Boolean visitArrayType(ArrayType t, Type s) {
934 if (s.hasTag(ARRAY)) {
935 if (t.elemtype.isPrimitive())
936 return isSameType(t.elemtype, elemtype(s));
937 else
938 return isSubtypeNoCapture(t.elemtype, elemtype(s));
939 }
941 if (s.hasTag(CLASS)) {
942 Name sname = s.tsym.getQualifiedName();
943 return sname == names.java_lang_Object
944 || sname == names.java_lang_Cloneable
945 || sname == names.java_io_Serializable;
946 }
948 return false;
949 }
951 @Override
952 public Boolean visitUndetVar(UndetVar t, Type s) {
953 //todo: test against origin needed? or replace with substitution?
954 if (t == s || t.qtype == s || s.hasTag(ERROR) || s.hasTag(UNKNOWN)) {
955 return true;
956 } else if (s.hasTag(BOT)) {
957 //if 's' is 'null' there's no instantiated type U for which
958 //U <: s (but 'null' itself, which is not a valid type)
959 return false;
960 }
962 t.addBound(InferenceBound.UPPER, s, Types.this);
963 return true;
964 }
966 @Override
967 public Boolean visitErrorType(ErrorType t, Type s) {
968 return true;
969 }
970 };
972 /**
973 * Is t a subtype of every type in given list `ts'?<br>
974 * (not defined for Method and ForAll types)<br>
975 * Allows unchecked conversions.
976 */
977 public boolean isSubtypeUnchecked(Type t, List<Type> ts, Warner warn) {
978 for (List<Type> l = ts; l.nonEmpty(); l = l.tail)
979 if (!isSubtypeUnchecked(t, l.head, warn))
980 return false;
981 return true;
982 }
984 /**
985 * Are corresponding elements of ts subtypes of ss? If lists are
986 * of different length, return false.
987 */
988 public boolean isSubtypes(List<Type> ts, List<Type> ss) {
989 while (ts.tail != null && ss.tail != null
990 /*inlined: ts.nonEmpty() && ss.nonEmpty()*/ &&
991 isSubtype(ts.head, ss.head)) {
992 ts = ts.tail;
993 ss = ss.tail;
994 }
995 return ts.tail == null && ss.tail == null;
996 /*inlined: ts.isEmpty() && ss.isEmpty();*/
997 }
999 /**
1000 * Are corresponding elements of ts subtypes of ss, allowing
1001 * unchecked conversions? If lists are of different length,
1002 * return false.
1003 **/
1004 public boolean isSubtypesUnchecked(List<Type> ts, List<Type> ss, Warner warn) {
1005 while (ts.tail != null && ss.tail != null
1006 /*inlined: ts.nonEmpty() && ss.nonEmpty()*/ &&
1007 isSubtypeUnchecked(ts.head, ss.head, warn)) {
1008 ts = ts.tail;
1009 ss = ss.tail;
1010 }
1011 return ts.tail == null && ss.tail == null;
1012 /*inlined: ts.isEmpty() && ss.isEmpty();*/
1013 }
1014 // </editor-fold>
1016 // <editor-fold defaultstate="collapsed" desc="isSuperType">
1017 /**
1018 * Is t a supertype of s?
1019 */
1020 public boolean isSuperType(Type t, Type s) {
1021 switch (t.getTag()) {
1022 case ERROR:
1023 return true;
1024 case UNDETVAR: {
1025 UndetVar undet = (UndetVar)t;
1026 if (t == s ||
1027 undet.qtype == s ||
1028 s.hasTag(ERROR) ||
1029 s.hasTag(BOT)) {
1030 return true;
1031 }
1032 undet.addBound(InferenceBound.LOWER, s, this);
1033 return true;
1034 }
1035 default:
1036 return isSubtype(s, t);
1037 }
1038 }
1039 // </editor-fold>
1041 // <editor-fold defaultstate="collapsed" desc="isSameType">
1042 /**
1043 * Are corresponding elements of the lists the same type? If
1044 * lists are of different length, return false.
1045 */
1046 public boolean isSameTypes(List<Type> ts, List<Type> ss) {
1047 return isSameTypes(ts, ss, false);
1048 }
1049 public boolean isSameTypes(List<Type> ts, List<Type> ss, boolean strict) {
1050 while (ts.tail != null && ss.tail != null
1051 /*inlined: ts.nonEmpty() && ss.nonEmpty()*/ &&
1052 isSameType(ts.head, ss.head, strict)) {
1053 ts = ts.tail;
1054 ss = ss.tail;
1055 }
1056 return ts.tail == null && ss.tail == null;
1057 /*inlined: ts.isEmpty() && ss.isEmpty();*/
1058 }
1060 /**
1061 * A polymorphic signature method (JLS SE 7, 8.4.1) is a method that
1062 * (i) is declared in the java.lang.invoke.MethodHandle class, (ii) takes
1063 * a single variable arity parameter (iii) whose declared type is Object[],
1064 * (iv) has a return type of Object and (v) is native.
1065 */
1066 public boolean isSignaturePolymorphic(MethodSymbol msym) {
1067 List<Type> argtypes = msym.type.getParameterTypes();
1068 return (msym.flags_field & NATIVE) != 0 &&
1069 msym.owner == syms.methodHandleType.tsym &&
1070 argtypes.tail.tail == null &&
1071 argtypes.head.hasTag(TypeTag.ARRAY) &&
1072 msym.type.getReturnType().tsym == syms.objectType.tsym &&
1073 ((ArrayType)argtypes.head).elemtype.tsym == syms.objectType.tsym;
1074 }
1076 /**
1077 * Is t the same type as s?
1078 */
1079 public boolean isSameType(Type t, Type s) {
1080 return isSameType(t, s, false);
1081 }
1082 public boolean isSameType(Type t, Type s, boolean strict) {
1083 return strict ?
1084 isSameTypeStrict.visit(t, s) :
1085 isSameTypeLoose.visit(t, s);
1086 }
1087 public boolean isSameAnnotatedType(Type t, Type s) {
1088 return isSameAnnotatedType.visit(t, s);
1089 }
1090 // where
1091 abstract class SameTypeVisitor extends TypeRelation {
1093 public Boolean visitType(Type t, Type s) {
1094 if (t == s)
1095 return true;
1097 if (s.isPartial())
1098 return visit(s, t);
1100 switch (t.getTag()) {
1101 case BYTE: case CHAR: case SHORT: case INT: case LONG: case FLOAT:
1102 case DOUBLE: case BOOLEAN: case VOID: case BOT: case NONE:
1103 return t.hasTag(s.getTag());
1104 case TYPEVAR: {
1105 if (s.hasTag(TYPEVAR)) {
1106 //type-substitution does not preserve type-var types
1107 //check that type var symbols and bounds are indeed the same
1108 return sameTypeVars((TypeVar)t.unannotatedType(), (TypeVar)s.unannotatedType());
1109 }
1110 else {
1111 //special case for s == ? super X, where upper(s) = u
1112 //check that u == t, where u has been set by Type.withTypeVar
1113 return s.isSuperBound() &&
1114 !s.isExtendsBound() &&
1115 visit(t, wildUpperBound(s));
1116 }
1117 }
1118 default:
1119 throw new AssertionError("isSameType " + t.getTag());
1120 }
1121 }
1123 abstract boolean sameTypeVars(TypeVar tv1, TypeVar tv2);
1125 @Override
1126 public Boolean visitWildcardType(WildcardType t, Type s) {
1127 if (s.isPartial())
1128 return visit(s, t);
1129 else
1130 return false;
1131 }
1133 @Override
1134 public Boolean visitClassType(ClassType t, Type s) {
1135 if (t == s)
1136 return true;
1138 if (s.isPartial())
1139 return visit(s, t);
1141 if (s.isSuperBound() && !s.isExtendsBound())
1142 return visit(t, wildUpperBound(s)) && visit(t, wildLowerBound(s));
1144 if (t.isCompound() && s.isCompound()) {
1145 if (!visit(supertype(t), supertype(s)))
1146 return false;
1148 HashSet<UniqueType> set = new HashSet<UniqueType>();
1149 for (Type x : interfaces(t))
1150 set.add(new UniqueType(x.unannotatedType(), Types.this));
1151 for (Type x : interfaces(s)) {
1152 if (!set.remove(new UniqueType(x.unannotatedType(), Types.this)))
1153 return false;
1154 }
1155 return (set.isEmpty());
1156 }
1157 return t.tsym == s.tsym
1158 && visit(t.getEnclosingType(), s.getEnclosingType())
1159 && containsTypes(t.getTypeArguments(), s.getTypeArguments());
1160 }
1162 abstract protected boolean containsTypes(List<Type> ts1, List<Type> ts2);
1164 @Override
1165 public Boolean visitArrayType(ArrayType t, Type s) {
1166 if (t == s)
1167 return true;
1169 if (s.isPartial())
1170 return visit(s, t);
1172 return s.hasTag(ARRAY)
1173 && containsTypeEquivalent(t.elemtype, elemtype(s));
1174 }
1176 @Override
1177 public Boolean visitMethodType(MethodType t, Type s) {
1178 // isSameType for methods does not take thrown
1179 // exceptions into account!
1180 return hasSameArgs(t, s) && visit(t.getReturnType(), s.getReturnType());
1181 }
1183 @Override
1184 public Boolean visitPackageType(PackageType t, Type s) {
1185 return t == s;
1186 }
1188 @Override
1189 public Boolean visitForAll(ForAll t, Type s) {
1190 if (!s.hasTag(FORALL)) {
1191 return false;
1192 }
1194 ForAll forAll = (ForAll)s;
1195 return hasSameBounds(t, forAll)
1196 && visit(t.qtype, subst(forAll.qtype, forAll.tvars, t.tvars));
1197 }
1199 @Override
1200 public Boolean visitUndetVar(UndetVar t, Type s) {
1201 if (s.hasTag(WILDCARD)) {
1202 // FIXME, this might be leftovers from before capture conversion
1203 return false;
1204 }
1206 if (t == s || t.qtype == s || s.hasTag(ERROR) || s.hasTag(UNKNOWN)) {
1207 return true;
1208 }
1210 t.addBound(InferenceBound.EQ, s, Types.this);
1212 return true;
1213 }
1215 @Override
1216 public Boolean visitErrorType(ErrorType t, Type s) {
1217 return true;
1218 }
1219 }
1221 /**
1222 * Standard type-equality relation - type variables are considered
1223 * equals if they share the same type symbol.
1224 */
1225 TypeRelation isSameTypeLoose = new LooseSameTypeVisitor();
1227 private class LooseSameTypeVisitor extends SameTypeVisitor {
1229 /** cache of the type-variable pairs being (recursively) tested. */
1230 private Set<TypePair> cache = new HashSet<>();
1232 @Override
1233 boolean sameTypeVars(TypeVar tv1, TypeVar tv2) {
1234 return tv1.tsym == tv2.tsym && checkSameBounds(tv1, tv2);
1235 }
1236 @Override
1237 protected boolean containsTypes(List<Type> ts1, List<Type> ts2) {
1238 return containsTypeEquivalent(ts1, ts2);
1239 }
1241 /**
1242 * Since type-variable bounds can be recursive, we need to protect against
1243 * infinite loops - where the same bounds are checked over and over recursively.
1244 */
1245 private boolean checkSameBounds(TypeVar tv1, TypeVar tv2) {
1246 TypePair p = new TypePair(tv1, tv2, true);
1247 if (cache.add(p)) {
1248 try {
1249 return visit(tv1.getUpperBound(), tv2.getUpperBound());
1250 } finally {
1251 cache.remove(p);
1252 }
1253 } else {
1254 return false;
1255 }
1256 }
1257 };
1259 /**
1260 * Strict type-equality relation - type variables are considered
1261 * equals if they share the same object identity.
1262 */
1263 TypeRelation isSameTypeStrict = new SameTypeVisitor() {
1264 @Override
1265 boolean sameTypeVars(TypeVar tv1, TypeVar tv2) {
1266 return tv1 == tv2;
1267 }
1268 @Override
1269 protected boolean containsTypes(List<Type> ts1, List<Type> ts2) {
1270 return isSameTypes(ts1, ts2, true);
1271 }
1273 @Override
1274 public Boolean visitWildcardType(WildcardType t, Type s) {
1275 if (!s.hasTag(WILDCARD)) {
1276 return false;
1277 } else {
1278 WildcardType t2 = (WildcardType)s.unannotatedType();
1279 return t.kind == t2.kind &&
1280 isSameType(t.type, t2.type, true);
1281 }
1282 }
1283 };
1285 /**
1286 * A version of LooseSameTypeVisitor that takes AnnotatedTypes
1287 * into account.
1288 */
1289 TypeRelation isSameAnnotatedType = new LooseSameTypeVisitor() {
1290 @Override
1291 public Boolean visitAnnotatedType(AnnotatedType t, Type s) {
1292 if (!s.isAnnotated())
1293 return false;
1294 if (!t.getAnnotationMirrors().containsAll(s.getAnnotationMirrors()))
1295 return false;
1296 if (!s.getAnnotationMirrors().containsAll(t.getAnnotationMirrors()))
1297 return false;
1298 return visit(t.unannotatedType(), s);
1299 }
1300 };
1301 // </editor-fold>
1303 // <editor-fold defaultstate="collapsed" desc="Contains Type">
1304 public boolean containedBy(Type t, Type s) {
1305 switch (t.getTag()) {
1306 case UNDETVAR:
1307 if (s.hasTag(WILDCARD)) {
1308 UndetVar undetvar = (UndetVar)t;
1309 WildcardType wt = (WildcardType)s.unannotatedType();
1310 switch(wt.kind) {
1311 case UNBOUND:
1312 break;
1313 case EXTENDS: {
1314 Type bound = wildUpperBound(s);
1315 undetvar.addBound(InferenceBound.UPPER, bound, this);
1316 break;
1317 }
1318 case SUPER: {
1319 Type bound = wildLowerBound(s);
1320 undetvar.addBound(InferenceBound.LOWER, bound, this);
1321 break;
1322 }
1323 }
1324 return true;
1325 } else {
1326 return isSameType(t, s);
1327 }
1328 case ERROR:
1329 return true;
1330 default:
1331 return containsType(s, t);
1332 }
1333 }
1335 boolean containsType(List<Type> ts, List<Type> ss) {
1336 while (ts.nonEmpty() && ss.nonEmpty()
1337 && containsType(ts.head, ss.head)) {
1338 ts = ts.tail;
1339 ss = ss.tail;
1340 }
1341 return ts.isEmpty() && ss.isEmpty();
1342 }
1344 /**
1345 * Check if t contains s.
1346 *
1347 * <p>T contains S if:
1348 *
1349 * <p>{@code L(T) <: L(S) && U(S) <: U(T)}
1350 *
1351 * <p>This relation is only used by ClassType.isSubtype(), that
1352 * is,
1353 *
1354 * <p>{@code C<S> <: C<T> if T contains S.}
1355 *
1356 * <p>Because of F-bounds, this relation can lead to infinite
1357 * recursion. Thus we must somehow break that recursion. Notice
1358 * that containsType() is only called from ClassType.isSubtype().
1359 * Since the arguments have already been checked against their
1360 * bounds, we know:
1361 *
1362 * <p>{@code U(S) <: U(T) if T is "super" bound (U(T) *is* the bound)}
1363 *
1364 * <p>{@code L(T) <: L(S) if T is "extends" bound (L(T) is bottom)}
1365 *
1366 * @param t a type
1367 * @param s a type
1368 */
1369 public boolean containsType(Type t, Type s) {
1370 return containsType.visit(t, s);
1371 }
1372 // where
1373 private TypeRelation containsType = new TypeRelation() {
1375 public Boolean visitType(Type t, Type s) {
1376 if (s.isPartial())
1377 return containedBy(s, t);
1378 else
1379 return isSameType(t, s);
1380 }
1382 // void debugContainsType(WildcardType t, Type s) {
1383 // System.err.println();
1384 // System.err.format(" does %s contain %s?%n", t, s);
1385 // System.err.format(" %s U(%s) <: U(%s) %s = %s%n",
1386 // wildUpperBound(s), s, t, wildUpperBound(t),
1387 // t.isSuperBound()
1388 // || isSubtypeNoCapture(wildUpperBound(s), wildUpperBound(t)));
1389 // System.err.format(" %s L(%s) <: L(%s) %s = %s%n",
1390 // wildLowerBound(t), t, s, wildLowerBound(s),
1391 // t.isExtendsBound()
1392 // || isSubtypeNoCapture(wildLowerBound(t), wildLowerBound(s)));
1393 // System.err.println();
1394 // }
1396 @Override
1397 public Boolean visitWildcardType(WildcardType t, Type s) {
1398 if (s.isPartial())
1399 return containedBy(s, t);
1400 else {
1401 // debugContainsType(t, s);
1402 return isSameWildcard(t, s)
1403 || t.type == s
1404 || isCaptureOf(s, t)
1405 || ((t.isExtendsBound() || isSubtypeNoCapture(wildLowerBound(t), cvarLowerBound(wildLowerBound(s)))) &&
1406 // TODO: JDK-8039214, cvarUpperBound call here is incorrect
1407 (t.isSuperBound() || isSubtypeNoCapture(cvarUpperBound(wildUpperBound(s)), wildUpperBound(t))));
1408 }
1409 }
1411 @Override
1412 public Boolean visitUndetVar(UndetVar t, Type s) {
1413 if (!s.hasTag(WILDCARD)) {
1414 return isSameType(t, s);
1415 } else {
1416 return false;
1417 }
1418 }
1420 @Override
1421 public Boolean visitErrorType(ErrorType t, Type s) {
1422 return true;
1423 }
1424 };
1426 public boolean isCaptureOf(Type s, WildcardType t) {
1427 if (!s.hasTag(TYPEVAR) || !((TypeVar)s.unannotatedType()).isCaptured())
1428 return false;
1429 return isSameWildcard(t, ((CapturedType)s.unannotatedType()).wildcard);
1430 }
1432 public boolean isSameWildcard(WildcardType t, Type s) {
1433 if (!s.hasTag(WILDCARD))
1434 return false;
1435 WildcardType w = (WildcardType)s.unannotatedType();
1436 return w.kind == t.kind && w.type == t.type;
1437 }
1439 public boolean containsTypeEquivalent(List<Type> ts, List<Type> ss) {
1440 while (ts.nonEmpty() && ss.nonEmpty()
1441 && containsTypeEquivalent(ts.head, ss.head)) {
1442 ts = ts.tail;
1443 ss = ss.tail;
1444 }
1445 return ts.isEmpty() && ss.isEmpty();
1446 }
1447 // </editor-fold>
1449 /**
1450 * Can t and s be compared for equality? Any primitive ==
1451 * primitive or primitive == object comparisons here are an error.
1452 * Unboxing and correct primitive == primitive comparisons are
1453 * already dealt with in Attr.visitBinary.
1454 *
1455 */
1456 public boolean isEqualityComparable(Type s, Type t, Warner warn) {
1457 if (t.isNumeric() && s.isNumeric())
1458 return true;
1460 boolean tPrimitive = t.isPrimitive();
1461 boolean sPrimitive = s.isPrimitive();
1462 if (!tPrimitive && !sPrimitive) {
1463 return isCastable(s, t, warn) || isCastable(t, s, warn);
1464 } else {
1465 return false;
1466 }
1467 }
1469 // <editor-fold defaultstate="collapsed" desc="isCastable">
1470 public boolean isCastable(Type t, Type s) {
1471 return isCastable(t, s, noWarnings);
1472 }
1474 /**
1475 * Is t is castable to s?<br>
1476 * s is assumed to be an erased type.<br>
1477 * (not defined for Method and ForAll types).
1478 */
1479 public boolean isCastable(Type t, Type s, Warner warn) {
1480 if (t == s)
1481 return true;
1483 if (t.isPrimitive() != s.isPrimitive())
1484 return allowBoxing && (
1485 isConvertible(t, s, warn)
1486 || (allowObjectToPrimitiveCast &&
1487 s.isPrimitive() &&
1488 isSubtype(boxedClass(s).type, t)));
1489 if (warn != warnStack.head) {
1490 try {
1491 warnStack = warnStack.prepend(warn);
1492 checkUnsafeVarargsConversion(t, s, warn);
1493 return isCastable.visit(t,s);
1494 } finally {
1495 warnStack = warnStack.tail;
1496 }
1497 } else {
1498 return isCastable.visit(t,s);
1499 }
1500 }
1501 // where
1502 private TypeRelation isCastable = new TypeRelation() {
1504 public Boolean visitType(Type t, Type s) {
1505 if (s.hasTag(ERROR))
1506 return true;
1508 switch (t.getTag()) {
1509 case BYTE: case CHAR: case SHORT: case INT: case LONG: case FLOAT:
1510 case DOUBLE:
1511 return s.isNumeric();
1512 case BOOLEAN:
1513 return s.hasTag(BOOLEAN);
1514 case VOID:
1515 return false;
1516 case BOT:
1517 return isSubtype(t, s);
1518 default:
1519 throw new AssertionError();
1520 }
1521 }
1523 @Override
1524 public Boolean visitWildcardType(WildcardType t, Type s) {
1525 return isCastable(wildUpperBound(t), s, warnStack.head);
1526 }
1528 @Override
1529 public Boolean visitClassType(ClassType t, Type s) {
1530 if (s.hasTag(ERROR) || s.hasTag(BOT))
1531 return true;
1533 if (s.hasTag(TYPEVAR)) {
1534 if (isCastable(t, s.getUpperBound(), noWarnings)) {
1535 warnStack.head.warn(LintCategory.UNCHECKED);
1536 return true;
1537 } else {
1538 return false;
1539 }
1540 }
1542 if (t.isCompound() || s.isCompound()) {
1543 return !t.isCompound() ?
1544 visitIntersectionType((IntersectionClassType)s.unannotatedType(), t, true) :
1545 visitIntersectionType((IntersectionClassType)t.unannotatedType(), s, false);
1546 }
1548 if (s.hasTag(CLASS) || s.hasTag(ARRAY)) {
1549 boolean upcast;
1550 if ((upcast = isSubtype(erasure(t), erasure(s)))
1551 || isSubtype(erasure(s), erasure(t))) {
1552 if (!upcast && s.hasTag(ARRAY)) {
1553 if (!isReifiable(s))
1554 warnStack.head.warn(LintCategory.UNCHECKED);
1555 return true;
1556 } else if (s.isRaw()) {
1557 return true;
1558 } else if (t.isRaw()) {
1559 if (!isUnbounded(s))
1560 warnStack.head.warn(LintCategory.UNCHECKED);
1561 return true;
1562 }
1563 // Assume |a| <: |b|
1564 final Type a = upcast ? t : s;
1565 final Type b = upcast ? s : t;
1566 final boolean HIGH = true;
1567 final boolean LOW = false;
1568 final boolean DONT_REWRITE_TYPEVARS = false;
1569 Type aHigh = rewriteQuantifiers(a, HIGH, DONT_REWRITE_TYPEVARS);
1570 Type aLow = rewriteQuantifiers(a, LOW, DONT_REWRITE_TYPEVARS);
1571 Type bHigh = rewriteQuantifiers(b, HIGH, DONT_REWRITE_TYPEVARS);
1572 Type bLow = rewriteQuantifiers(b, LOW, DONT_REWRITE_TYPEVARS);
1573 Type lowSub = asSub(bLow, aLow.tsym);
1574 Type highSub = (lowSub == null) ? null : asSub(bHigh, aHigh.tsym);
1575 if (highSub == null) {
1576 final boolean REWRITE_TYPEVARS = true;
1577 aHigh = rewriteQuantifiers(a, HIGH, REWRITE_TYPEVARS);
1578 aLow = rewriteQuantifiers(a, LOW, REWRITE_TYPEVARS);
1579 bHigh = rewriteQuantifiers(b, HIGH, REWRITE_TYPEVARS);
1580 bLow = rewriteQuantifiers(b, LOW, REWRITE_TYPEVARS);
1581 lowSub = asSub(bLow, aLow.tsym);
1582 highSub = (lowSub == null) ? null : asSub(bHigh, aHigh.tsym);
1583 }
1584 if (highSub != null) {
1585 if (!(a.tsym == highSub.tsym && a.tsym == lowSub.tsym)) {
1586 Assert.error(a.tsym + " != " + highSub.tsym + " != " + lowSub.tsym);
1587 }
1588 if (!disjointTypes(aHigh.allparams(), highSub.allparams())
1589 && !disjointTypes(aHigh.allparams(), lowSub.allparams())
1590 && !disjointTypes(aLow.allparams(), highSub.allparams())
1591 && !disjointTypes(aLow.allparams(), lowSub.allparams())) {
1592 if (upcast ? giveWarning(a, b) :
1593 giveWarning(b, a))
1594 warnStack.head.warn(LintCategory.UNCHECKED);
1595 return true;
1596 }
1597 }
1598 if (isReifiable(s))
1599 return isSubtypeUnchecked(a, b);
1600 else
1601 return isSubtypeUnchecked(a, b, warnStack.head);
1602 }
1604 // Sidecast
1605 if (s.hasTag(CLASS)) {
1606 if ((s.tsym.flags() & INTERFACE) != 0) {
1607 return ((t.tsym.flags() & FINAL) == 0)
1608 ? sideCast(t, s, warnStack.head)
1609 : sideCastFinal(t, s, warnStack.head);
1610 } else if ((t.tsym.flags() & INTERFACE) != 0) {
1611 return ((s.tsym.flags() & FINAL) == 0)
1612 ? sideCast(t, s, warnStack.head)
1613 : sideCastFinal(t, s, warnStack.head);
1614 } else {
1615 // unrelated class types
1616 return false;
1617 }
1618 }
1619 }
1620 return false;
1621 }
1623 boolean visitIntersectionType(IntersectionClassType ict, Type s, boolean reverse) {
1624 Warner warn = noWarnings;
1625 for (Type c : ict.getComponents()) {
1626 warn.clear();
1627 if (reverse ? !isCastable(s, c, warn) : !isCastable(c, s, warn))
1628 return false;
1629 }
1630 if (warn.hasLint(LintCategory.UNCHECKED))
1631 warnStack.head.warn(LintCategory.UNCHECKED);
1632 return true;
1633 }
1635 @Override
1636 public Boolean visitArrayType(ArrayType t, Type s) {
1637 switch (s.getTag()) {
1638 case ERROR:
1639 case BOT:
1640 return true;
1641 case TYPEVAR:
1642 if (isCastable(s, t, noWarnings)) {
1643 warnStack.head.warn(LintCategory.UNCHECKED);
1644 return true;
1645 } else {
1646 return false;
1647 }
1648 case CLASS:
1649 return isSubtype(t, s);
1650 case ARRAY:
1651 if (elemtype(t).isPrimitive() || elemtype(s).isPrimitive()) {
1652 return elemtype(t).hasTag(elemtype(s).getTag());
1653 } else {
1654 return visit(elemtype(t), elemtype(s));
1655 }
1656 default:
1657 return false;
1658 }
1659 }
1661 @Override
1662 public Boolean visitTypeVar(TypeVar t, Type s) {
1663 switch (s.getTag()) {
1664 case ERROR:
1665 case BOT:
1666 return true;
1667 case TYPEVAR:
1668 if (isSubtype(t, s)) {
1669 return true;
1670 } else if (isCastable(t.bound, s, noWarnings)) {
1671 warnStack.head.warn(LintCategory.UNCHECKED);
1672 return true;
1673 } else {
1674 return false;
1675 }
1676 default:
1677 return isCastable(t.bound, s, warnStack.head);
1678 }
1679 }
1681 @Override
1682 public Boolean visitErrorType(ErrorType t, Type s) {
1683 return true;
1684 }
1685 };
1686 // </editor-fold>
1688 // <editor-fold defaultstate="collapsed" desc="disjointTypes">
1689 public boolean disjointTypes(List<Type> ts, List<Type> ss) {
1690 while (ts.tail != null && ss.tail != null) {
1691 if (disjointType(ts.head, ss.head)) return true;
1692 ts = ts.tail;
1693 ss = ss.tail;
1694 }
1695 return false;
1696 }
1698 /**
1699 * Two types or wildcards are considered disjoint if it can be
1700 * proven that no type can be contained in both. It is
1701 * conservative in that it is allowed to say that two types are
1702 * not disjoint, even though they actually are.
1703 *
1704 * The type {@code C<X>} is castable to {@code C<Y>} exactly if
1705 * {@code X} and {@code Y} are not disjoint.
1706 */
1707 public boolean disjointType(Type t, Type s) {
1708 return disjointType.visit(t, s);
1709 }
1710 // where
1711 private TypeRelation disjointType = new TypeRelation() {
1713 private Set<TypePair> cache = new HashSet<TypePair>();
1715 @Override
1716 public Boolean visitType(Type t, Type s) {
1717 if (s.hasTag(WILDCARD))
1718 return visit(s, t);
1719 else
1720 return notSoftSubtypeRecursive(t, s) || notSoftSubtypeRecursive(s, t);
1721 }
1723 private boolean isCastableRecursive(Type t, Type s) {
1724 TypePair pair = new TypePair(t, s);
1725 if (cache.add(pair)) {
1726 try {
1727 return Types.this.isCastable(t, s);
1728 } finally {
1729 cache.remove(pair);
1730 }
1731 } else {
1732 return true;
1733 }
1734 }
1736 private boolean notSoftSubtypeRecursive(Type t, Type s) {
1737 TypePair pair = new TypePair(t, s);
1738 if (cache.add(pair)) {
1739 try {
1740 return Types.this.notSoftSubtype(t, s);
1741 } finally {
1742 cache.remove(pair);
1743 }
1744 } else {
1745 return false;
1746 }
1747 }
1749 @Override
1750 public Boolean visitWildcardType(WildcardType t, Type s) {
1751 if (t.isUnbound())
1752 return false;
1754 if (!s.hasTag(WILDCARD)) {
1755 if (t.isExtendsBound())
1756 return notSoftSubtypeRecursive(s, t.type);
1757 else
1758 return notSoftSubtypeRecursive(t.type, s);
1759 }
1761 if (s.isUnbound())
1762 return false;
1764 if (t.isExtendsBound()) {
1765 if (s.isExtendsBound())
1766 return !isCastableRecursive(t.type, wildUpperBound(s));
1767 else if (s.isSuperBound())
1768 return notSoftSubtypeRecursive(wildLowerBound(s), t.type);
1769 } else if (t.isSuperBound()) {
1770 if (s.isExtendsBound())
1771 return notSoftSubtypeRecursive(t.type, wildUpperBound(s));
1772 }
1773 return false;
1774 }
1775 };
1776 // </editor-fold>
1778 // <editor-fold defaultstate="collapsed" desc="cvarLowerBounds">
1779 public List<Type> cvarLowerBounds(List<Type> ts) {
1780 return map(ts, cvarLowerBoundMapping);
1781 }
1782 private final Mapping cvarLowerBoundMapping = new Mapping("cvarLowerBound") {
1783 public Type apply(Type t) {
1784 return cvarLowerBound(t);
1785 }
1786 };
1787 // </editor-fold>
1789 // <editor-fold defaultstate="collapsed" desc="notSoftSubtype">
1790 /**
1791 * This relation answers the question: is impossible that
1792 * something of type `t' can be a subtype of `s'? This is
1793 * different from the question "is `t' not a subtype of `s'?"
1794 * when type variables are involved: Integer is not a subtype of T
1795 * where {@code <T extends Number>} but it is not true that Integer cannot
1796 * possibly be a subtype of T.
1797 */
1798 public boolean notSoftSubtype(Type t, Type s) {
1799 if (t == s) return false;
1800 if (t.hasTag(TYPEVAR)) {
1801 TypeVar tv = (TypeVar) t;
1802 return !isCastable(tv.bound,
1803 relaxBound(s),
1804 noWarnings);
1805 }
1806 if (!s.hasTag(WILDCARD))
1807 s = cvarUpperBound(s);
1809 return !isSubtype(t, relaxBound(s));
1810 }
1812 private Type relaxBound(Type t) {
1813 if (t.hasTag(TYPEVAR)) {
1814 while (t.hasTag(TYPEVAR))
1815 t = t.getUpperBound();
1816 t = rewriteQuantifiers(t, true, true);
1817 }
1818 return t;
1819 }
1820 // </editor-fold>
1822 // <editor-fold defaultstate="collapsed" desc="isReifiable">
1823 public boolean isReifiable(Type t) {
1824 return isReifiable.visit(t);
1825 }
1826 // where
1827 private UnaryVisitor<Boolean> isReifiable = new UnaryVisitor<Boolean>() {
1829 public Boolean visitType(Type t, Void ignored) {
1830 return true;
1831 }
1833 @Override
1834 public Boolean visitClassType(ClassType t, Void ignored) {
1835 if (t.isCompound())
1836 return false;
1837 else {
1838 if (!t.isParameterized())
1839 return true;
1841 for (Type param : t.allparams()) {
1842 if (!param.isUnbound())
1843 return false;
1844 }
1845 return true;
1846 }
1847 }
1849 @Override
1850 public Boolean visitArrayType(ArrayType t, Void ignored) {
1851 return visit(t.elemtype);
1852 }
1854 @Override
1855 public Boolean visitTypeVar(TypeVar t, Void ignored) {
1856 return false;
1857 }
1858 };
1859 // </editor-fold>
1861 // <editor-fold defaultstate="collapsed" desc="Array Utils">
1862 public boolean isArray(Type t) {
1863 while (t.hasTag(WILDCARD))
1864 t = wildUpperBound(t);
1865 return t.hasTag(ARRAY);
1866 }
1868 /**
1869 * The element type of an array.
1870 */
1871 public Type elemtype(Type t) {
1872 switch (t.getTag()) {
1873 case WILDCARD:
1874 return elemtype(wildUpperBound(t));
1875 case ARRAY:
1876 t = t.unannotatedType();
1877 return ((ArrayType)t).elemtype;
1878 case FORALL:
1879 return elemtype(((ForAll)t).qtype);
1880 case ERROR:
1881 return t;
1882 default:
1883 return null;
1884 }
1885 }
1887 public Type elemtypeOrType(Type t) {
1888 Type elemtype = elemtype(t);
1889 return elemtype != null ?
1890 elemtype :
1891 t;
1892 }
1894 /**
1895 * Mapping to take element type of an arraytype
1896 */
1897 private Mapping elemTypeFun = new Mapping ("elemTypeFun") {
1898 public Type apply(Type t) {
1899 while (t.hasTag(TYPEVAR)) {
1900 t = t.getUpperBound();
1901 }
1902 return elemtype(t);
1903 }
1904 };
1906 /**
1907 * The number of dimensions of an array type.
1908 */
1909 public int dimensions(Type t) {
1910 int result = 0;
1911 while (t.hasTag(ARRAY)) {
1912 result++;
1913 t = elemtype(t);
1914 }
1915 return result;
1916 }
1918 /**
1919 * Returns an ArrayType with the component type t
1920 *
1921 * @param t The component type of the ArrayType
1922 * @return the ArrayType for the given component
1923 */
1924 public ArrayType makeArrayType(Type t) {
1925 if (t.hasTag(VOID) || t.hasTag(PACKAGE)) {
1926 Assert.error("Type t must not be a VOID or PACKAGE type, " + t.toString());
1927 }
1928 return new ArrayType(t, syms.arrayClass);
1929 }
1930 // </editor-fold>
1932 // <editor-fold defaultstate="collapsed" desc="asSuper">
1933 /**
1934 * Return the (most specific) base type of t that starts with the
1935 * given symbol. If none exists, return null.
1936 *
1937 * @param t a type
1938 * @param sym a symbol
1939 */
1940 public Type asSuper(Type t, Symbol sym) {
1941 /* Some examples:
1942 *
1943 * (Enum<E>, Comparable) => Comparable<E>
1944 * (c.s.s.d.AttributeTree.ValueKind, Enum) => Enum<c.s.s.d.AttributeTree.ValueKind>
1945 * (c.s.s.t.ExpressionTree, c.s.s.t.Tree) => c.s.s.t.Tree
1946 * (j.u.List<capture#160 of ? extends c.s.s.d.DocTree>, Iterable) =>
1947 * Iterable<capture#160 of ? extends c.s.s.d.DocTree>
1948 */
1949 if (sym.type == syms.objectType) { //optimization
1950 return syms.objectType;
1951 }
1952 return asSuper.visit(t, sym);
1953 }
1954 // where
1955 private SimpleVisitor<Type,Symbol> asSuper = new SimpleVisitor<Type,Symbol>() {
1957 public Type visitType(Type t, Symbol sym) {
1958 return null;
1959 }
1961 @Override
1962 public Type visitClassType(ClassType t, Symbol sym) {
1963 if (t.tsym == sym)
1964 return t;
1966 Type st = supertype(t);
1967 if (st.hasTag(CLASS) || st.hasTag(TYPEVAR)) {
1968 Type x = asSuper(st, sym);
1969 if (x != null)
1970 return x;
1971 }
1972 if ((sym.flags() & INTERFACE) != 0) {
1973 for (List<Type> l = interfaces(t); l.nonEmpty(); l = l.tail) {
1974 if (!l.head.hasTag(ERROR)) {
1975 Type x = asSuper(l.head, sym);
1976 if (x != null)
1977 return x;
1978 }
1979 }
1980 }
1981 return null;
1982 }
1984 @Override
1985 public Type visitArrayType(ArrayType t, Symbol sym) {
1986 return isSubtype(t, sym.type) ? sym.type : null;
1987 }
1989 @Override
1990 public Type visitTypeVar(TypeVar t, Symbol sym) {
1991 if (t.tsym == sym)
1992 return t;
1993 else
1994 return asSuper(t.bound, sym);
1995 }
1997 @Override
1998 public Type visitErrorType(ErrorType t, Symbol sym) {
1999 return t;
2000 }
2001 };
2003 /**
2004 * Return the base type of t or any of its outer types that starts
2005 * with the given symbol. If none exists, return null.
2006 *
2007 * @param t a type
2008 * @param sym a symbol
2009 */
2010 public Type asOuterSuper(Type t, Symbol sym) {
2011 switch (t.getTag()) {
2012 case CLASS:
2013 do {
2014 Type s = asSuper(t, sym);
2015 if (s != null) return s;
2016 t = t.getEnclosingType();
2017 } while (t.hasTag(CLASS));
2018 return null;
2019 case ARRAY:
2020 return isSubtype(t, sym.type) ? sym.type : null;
2021 case TYPEVAR:
2022 return asSuper(t, sym);
2023 case ERROR:
2024 return t;
2025 default:
2026 return null;
2027 }
2028 }
2030 /**
2031 * Return the base type of t or any of its enclosing types that
2032 * starts with the given symbol. If none exists, return null.
2033 *
2034 * @param t a type
2035 * @param sym a symbol
2036 */
2037 public Type asEnclosingSuper(Type t, Symbol sym) {
2038 switch (t.getTag()) {
2039 case CLASS:
2040 do {
2041 Type s = asSuper(t, sym);
2042 if (s != null) return s;
2043 Type outer = t.getEnclosingType();
2044 t = (outer.hasTag(CLASS)) ? outer :
2045 (t.tsym.owner.enclClass() != null) ? t.tsym.owner.enclClass().type :
2046 Type.noType;
2047 } while (t.hasTag(CLASS));
2048 return null;
2049 case ARRAY:
2050 return isSubtype(t, sym.type) ? sym.type : null;
2051 case TYPEVAR:
2052 return asSuper(t, sym);
2053 case ERROR:
2054 return t;
2055 default:
2056 return null;
2057 }
2058 }
2059 // </editor-fold>
2061 // <editor-fold defaultstate="collapsed" desc="memberType">
2062 /**
2063 * The type of given symbol, seen as a member of t.
2064 *
2065 * @param t a type
2066 * @param sym a symbol
2067 */
2068 public Type memberType(Type t, Symbol sym) {
2069 return (sym.flags() & STATIC) != 0
2070 ? sym.type
2071 : memberType.visit(t, sym);
2072 }
2073 // where
2074 private SimpleVisitor<Type,Symbol> memberType = new SimpleVisitor<Type,Symbol>() {
2076 public Type visitType(Type t, Symbol sym) {
2077 return sym.type;
2078 }
2080 @Override
2081 public Type visitWildcardType(WildcardType t, Symbol sym) {
2082 return memberType(wildUpperBound(t), sym);
2083 }
2085 @Override
2086 public Type visitClassType(ClassType t, Symbol sym) {
2087 Symbol owner = sym.owner;
2088 long flags = sym.flags();
2089 if (((flags & STATIC) == 0) && owner.type.isParameterized()) {
2090 Type base = asOuterSuper(t, owner);
2091 //if t is an intersection type T = CT & I1 & I2 ... & In
2092 //its supertypes CT, I1, ... In might contain wildcards
2093 //so we need to go through capture conversion
2094 base = t.isCompound() ? capture(base) : base;
2095 if (base != null) {
2096 List<Type> ownerParams = owner.type.allparams();
2097 List<Type> baseParams = base.allparams();
2098 if (ownerParams.nonEmpty()) {
2099 if (baseParams.isEmpty()) {
2100 // then base is a raw type
2101 return erasure(sym.type);
2102 } else {
2103 return subst(sym.type, ownerParams, baseParams);
2104 }
2105 }
2106 }
2107 }
2108 return sym.type;
2109 }
2111 @Override
2112 public Type visitTypeVar(TypeVar t, Symbol sym) {
2113 return memberType(t.bound, sym);
2114 }
2116 @Override
2117 public Type visitErrorType(ErrorType t, Symbol sym) {
2118 return t;
2119 }
2120 };
2121 // </editor-fold>
2123 // <editor-fold defaultstate="collapsed" desc="isAssignable">
2124 public boolean isAssignable(Type t, Type s) {
2125 return isAssignable(t, s, noWarnings);
2126 }
2128 /**
2129 * Is t assignable to s?<br>
2130 * Equivalent to subtype except for constant values and raw
2131 * types.<br>
2132 * (not defined for Method and ForAll types)
2133 */
2134 public boolean isAssignable(Type t, Type s, Warner warn) {
2135 if (t.hasTag(ERROR))
2136 return true;
2137 if (t.getTag().isSubRangeOf(INT) && t.constValue() != null) {
2138 int value = ((Number)t.constValue()).intValue();
2139 switch (s.getTag()) {
2140 case BYTE:
2141 if (Byte.MIN_VALUE <= value && value <= Byte.MAX_VALUE)
2142 return true;
2143 break;
2144 case CHAR:
2145 if (Character.MIN_VALUE <= value && value <= Character.MAX_VALUE)
2146 return true;
2147 break;
2148 case SHORT:
2149 if (Short.MIN_VALUE <= value && value <= Short.MAX_VALUE)
2150 return true;
2151 break;
2152 case INT:
2153 return true;
2154 case CLASS:
2155 switch (unboxedType(s).getTag()) {
2156 case BYTE:
2157 case CHAR:
2158 case SHORT:
2159 return isAssignable(t, unboxedType(s), warn);
2160 }
2161 break;
2162 }
2163 }
2164 return isConvertible(t, s, warn);
2165 }
2166 // </editor-fold>
2168 // <editor-fold defaultstate="collapsed" desc="erasure">
2169 /**
2170 * The erasure of t {@code |t|} -- the type that results when all
2171 * type parameters in t are deleted.
2172 */
2173 public Type erasure(Type t) {
2174 return eraseNotNeeded(t)? t : erasure(t, false);
2175 }
2176 //where
2177 private boolean eraseNotNeeded(Type t) {
2178 // We don't want to erase primitive types and String type as that
2179 // operation is idempotent. Also, erasing these could result in loss
2180 // of information such as constant values attached to such types.
2181 return (t.isPrimitive()) || (syms.stringType.tsym == t.tsym);
2182 }
2184 private Type erasure(Type t, boolean recurse) {
2185 if (t.isPrimitive())
2186 return t; /* fast special case */
2187 else
2188 return erasure.visit(t, recurse);
2189 }
2190 // where
2191 private SimpleVisitor<Type, Boolean> erasure = new SimpleVisitor<Type, Boolean>() {
2192 public Type visitType(Type t, Boolean recurse) {
2193 if (t.isPrimitive())
2194 return t; /*fast special case*/
2195 else
2196 return t.map(recurse ? erasureRecFun : erasureFun);
2197 }
2199 @Override
2200 public Type visitWildcardType(WildcardType t, Boolean recurse) {
2201 return erasure(wildUpperBound(t), recurse);
2202 }
2204 @Override
2205 public Type visitClassType(ClassType t, Boolean recurse) {
2206 Type erased = t.tsym.erasure(Types.this);
2207 if (recurse) {
2208 erased = new ErasedClassType(erased.getEnclosingType(),erased.tsym);
2209 }
2210 return erased;
2211 }
2213 @Override
2214 public Type visitTypeVar(TypeVar t, Boolean recurse) {
2215 return erasure(t.bound, recurse);
2216 }
2218 @Override
2219 public Type visitErrorType(ErrorType t, Boolean recurse) {
2220 return t;
2221 }
2223 @Override
2224 public Type visitAnnotatedType(AnnotatedType t, Boolean recurse) {
2225 Type erased = erasure(t.unannotatedType(), recurse);
2226 if (erased.isAnnotated()) {
2227 // This can only happen when the underlying type is a
2228 // type variable and the upper bound of it is annotated.
2229 // The annotation on the type variable overrides the one
2230 // on the bound.
2231 erased = ((AnnotatedType)erased).unannotatedType();
2232 }
2233 return erased.annotatedType(t.getAnnotationMirrors());
2234 }
2235 };
2237 private Mapping erasureFun = new Mapping ("erasure") {
2238 public Type apply(Type t) { return erasure(t); }
2239 };
2241 private Mapping erasureRecFun = new Mapping ("erasureRecursive") {
2242 public Type apply(Type t) { return erasureRecursive(t); }
2243 };
2245 public List<Type> erasure(List<Type> ts) {
2246 return Type.map(ts, erasureFun);
2247 }
2249 public Type erasureRecursive(Type t) {
2250 return erasure(t, true);
2251 }
2253 public List<Type> erasureRecursive(List<Type> ts) {
2254 return Type.map(ts, erasureRecFun);
2255 }
2256 // </editor-fold>
2258 // <editor-fold defaultstate="collapsed" desc="makeCompoundType">
2259 /**
2260 * Make a compound type from non-empty list of types. The list should be
2261 * ordered according to {@link Symbol#precedes(TypeSymbol,Types)}.
2262 *
2263 * @param bounds the types from which the compound type is formed
2264 * @param supertype is objectType if all bounds are interfaces,
2265 * null otherwise.
2266 */
2267 public Type makeCompoundType(List<Type> bounds) {
2268 return makeCompoundType(bounds, bounds.head.tsym.isInterface());
2269 }
2270 public Type makeCompoundType(List<Type> bounds, boolean allInterfaces) {
2271 Assert.check(bounds.nonEmpty());
2272 Type firstExplicitBound = bounds.head;
2273 if (allInterfaces) {
2274 bounds = bounds.prepend(syms.objectType);
2275 }
2276 ClassSymbol bc =
2277 new ClassSymbol(ABSTRACT|PUBLIC|SYNTHETIC|COMPOUND|ACYCLIC,
2278 Type.moreInfo
2279 ? names.fromString(bounds.toString())
2280 : names.empty,
2281 null,
2282 syms.noSymbol);
2283 bc.type = new IntersectionClassType(bounds, bc, allInterfaces);
2284 bc.erasure_field = (bounds.head.hasTag(TYPEVAR)) ?
2285 syms.objectType : // error condition, recover
2286 erasure(firstExplicitBound);
2287 bc.members_field = new Scope(bc);
2288 return bc.type;
2289 }
2291 /**
2292 * A convenience wrapper for {@link #makeCompoundType(List)}; the
2293 * arguments are converted to a list and passed to the other
2294 * method. Note that this might cause a symbol completion.
2295 * Hence, this version of makeCompoundType may not be called
2296 * during a classfile read.
2297 */
2298 public Type makeCompoundType(Type bound1, Type bound2) {
2299 return makeCompoundType(List.of(bound1, bound2));
2300 }
2301 // </editor-fold>
2303 // <editor-fold defaultstate="collapsed" desc="supertype">
2304 public Type supertype(Type t) {
2305 return supertype.visit(t);
2306 }
2307 // where
2308 private UnaryVisitor<Type> supertype = new UnaryVisitor<Type>() {
2310 public Type visitType(Type t, Void ignored) {
2311 // A note on wildcards: there is no good way to
2312 // determine a supertype for a super bounded wildcard.
2313 return Type.noType;
2314 }
2316 @Override
2317 public Type visitClassType(ClassType t, Void ignored) {
2318 if (t.supertype_field == null) {
2319 Type supertype = ((ClassSymbol)t.tsym).getSuperclass();
2320 // An interface has no superclass; its supertype is Object.
2321 if (t.isInterface())
2322 supertype = ((ClassType)t.tsym.type).supertype_field;
2323 if (t.supertype_field == null) {
2324 List<Type> actuals = classBound(t).allparams();
2325 List<Type> formals = t.tsym.type.allparams();
2326 if (t.hasErasedSupertypes()) {
2327 t.supertype_field = erasureRecursive(supertype);
2328 } else if (formals.nonEmpty()) {
2329 t.supertype_field = subst(supertype, formals, actuals);
2330 }
2331 else {
2332 t.supertype_field = supertype;
2333 }
2334 }
2335 }
2336 return t.supertype_field;
2337 }
2339 /**
2340 * The supertype is always a class type. If the type
2341 * variable's bounds start with a class type, this is also
2342 * the supertype. Otherwise, the supertype is
2343 * java.lang.Object.
2344 */
2345 @Override
2346 public Type visitTypeVar(TypeVar t, Void ignored) {
2347 if (t.bound.hasTag(TYPEVAR) ||
2348 (!t.bound.isCompound() && !t.bound.isInterface())) {
2349 return t.bound;
2350 } else {
2351 return supertype(t.bound);
2352 }
2353 }
2355 @Override
2356 public Type visitArrayType(ArrayType t, Void ignored) {
2357 if (t.elemtype.isPrimitive() || isSameType(t.elemtype, syms.objectType))
2358 return arraySuperType();
2359 else
2360 return new ArrayType(supertype(t.elemtype), t.tsym);
2361 }
2363 @Override
2364 public Type visitErrorType(ErrorType t, Void ignored) {
2365 return Type.noType;
2366 }
2367 };
2368 // </editor-fold>
2370 // <editor-fold defaultstate="collapsed" desc="interfaces">
2371 /**
2372 * Return the interfaces implemented by this class.
2373 */
2374 public List<Type> interfaces(Type t) {
2375 return interfaces.visit(t);
2376 }
2377 // where
2378 private UnaryVisitor<List<Type>> interfaces = new UnaryVisitor<List<Type>>() {
2380 public List<Type> visitType(Type t, Void ignored) {
2381 return List.nil();
2382 }
2384 @Override
2385 public List<Type> visitClassType(ClassType t, Void ignored) {
2386 if (t.interfaces_field == null) {
2387 List<Type> interfaces = ((ClassSymbol)t.tsym).getInterfaces();
2388 if (t.interfaces_field == null) {
2389 // If t.interfaces_field is null, then t must
2390 // be a parameterized type (not to be confused
2391 // with a generic type declaration).
2392 // Terminology:
2393 // Parameterized type: List<String>
2394 // Generic type declaration: class List<E> { ... }
2395 // So t corresponds to List<String> and
2396 // t.tsym.type corresponds to List<E>.
2397 // The reason t must be parameterized type is
2398 // that completion will happen as a side
2399 // effect of calling
2400 // ClassSymbol.getInterfaces. Since
2401 // t.interfaces_field is null after
2402 // completion, we can assume that t is not the
2403 // type of a class/interface declaration.
2404 Assert.check(t != t.tsym.type, t);
2405 List<Type> actuals = t.allparams();
2406 List<Type> formals = t.tsym.type.allparams();
2407 if (t.hasErasedSupertypes()) {
2408 t.interfaces_field = erasureRecursive(interfaces);
2409 } else if (formals.nonEmpty()) {
2410 t.interfaces_field = subst(interfaces, formals, actuals);
2411 }
2412 else {
2413 t.interfaces_field = interfaces;
2414 }
2415 }
2416 }
2417 return t.interfaces_field;
2418 }
2420 @Override
2421 public List<Type> visitTypeVar(TypeVar t, Void ignored) {
2422 if (t.bound.isCompound())
2423 return interfaces(t.bound);
2425 if (t.bound.isInterface())
2426 return List.of(t.bound);
2428 return List.nil();
2429 }
2430 };
2432 public List<Type> directSupertypes(Type t) {
2433 return directSupertypes.visit(t);
2434 }
2435 // where
2436 private final UnaryVisitor<List<Type>> directSupertypes = new UnaryVisitor<List<Type>>() {
2438 public List<Type> visitType(final Type type, final Void ignored) {
2439 if (!type.isCompound()) {
2440 final Type sup = supertype(type);
2441 return (sup == Type.noType || sup == type || sup == null)
2442 ? interfaces(type)
2443 : interfaces(type).prepend(sup);
2444 } else {
2445 return visitIntersectionType((IntersectionClassType) type);
2446 }
2447 }
2449 private List<Type> visitIntersectionType(final IntersectionClassType it) {
2450 return it.getExplicitComponents();
2451 }
2453 };
2455 public boolean isDirectSuperInterface(TypeSymbol isym, TypeSymbol origin) {
2456 for (Type i2 : interfaces(origin.type)) {
2457 if (isym == i2.tsym) return true;
2458 }
2459 return false;
2460 }
2461 // </editor-fold>
2463 // <editor-fold defaultstate="collapsed" desc="isDerivedRaw">
2464 Map<Type,Boolean> isDerivedRawCache = new HashMap<Type,Boolean>();
2466 public boolean isDerivedRaw(Type t) {
2467 Boolean result = isDerivedRawCache.get(t);
2468 if (result == null) {
2469 result = isDerivedRawInternal(t);
2470 isDerivedRawCache.put(t, result);
2471 }
2472 return result;
2473 }
2475 public boolean isDerivedRawInternal(Type t) {
2476 if (t.isErroneous())
2477 return false;
2478 return
2479 t.isRaw() ||
2480 supertype(t) != Type.noType && isDerivedRaw(supertype(t)) ||
2481 isDerivedRaw(interfaces(t));
2482 }
2484 public boolean isDerivedRaw(List<Type> ts) {
2485 List<Type> l = ts;
2486 while (l.nonEmpty() && !isDerivedRaw(l.head)) l = l.tail;
2487 return l.nonEmpty();
2488 }
2489 // </editor-fold>
2491 // <editor-fold defaultstate="collapsed" desc="setBounds">
2492 /**
2493 * Set the bounds field of the given type variable to reflect a
2494 * (possibly multiple) list of bounds.
2495 * @param t a type variable
2496 * @param bounds the bounds, must be nonempty
2497 * @param supertype is objectType if all bounds are interfaces,
2498 * null otherwise.
2499 */
2500 public void setBounds(TypeVar t, List<Type> bounds) {
2501 setBounds(t, bounds, bounds.head.tsym.isInterface());
2502 }
2504 /**
2505 * Same as {@link #setBounds(Type.TypeVar,List,Type)}, except that
2506 * third parameter is computed directly, as follows: if all
2507 * all bounds are interface types, the computed supertype is Object,
2508 * otherwise the supertype is simply left null (in this case, the supertype
2509 * is assumed to be the head of the bound list passed as second argument).
2510 * Note that this check might cause a symbol completion. Hence, this version of
2511 * setBounds may not be called during a classfile read.
2512 */
2513 public void setBounds(TypeVar t, List<Type> bounds, boolean allInterfaces) {
2514 t.bound = bounds.tail.isEmpty() ?
2515 bounds.head :
2516 makeCompoundType(bounds, allInterfaces);
2517 t.rank_field = -1;
2518 }
2519 // </editor-fold>
2521 // <editor-fold defaultstate="collapsed" desc="getBounds">
2522 /**
2523 * Return list of bounds of the given type variable.
2524 */
2525 public List<Type> getBounds(TypeVar t) {
2526 if (t.bound.hasTag(NONE))
2527 return List.nil();
2528 else if (t.bound.isErroneous() || !t.bound.isCompound())
2529 return List.of(t.bound);
2530 else if ((erasure(t).tsym.flags() & INTERFACE) == 0)
2531 return interfaces(t).prepend(supertype(t));
2532 else
2533 // No superclass was given in bounds.
2534 // In this case, supertype is Object, erasure is first interface.
2535 return interfaces(t);
2536 }
2537 // </editor-fold>
2539 // <editor-fold defaultstate="collapsed" desc="classBound">
2540 /**
2541 * If the given type is a (possibly selected) type variable,
2542 * return the bounding class of this type, otherwise return the
2543 * type itself.
2544 */
2545 public Type classBound(Type t) {
2546 return classBound.visit(t);
2547 }
2548 // where
2549 private UnaryVisitor<Type> classBound = new UnaryVisitor<Type>() {
2551 public Type visitType(Type t, Void ignored) {
2552 return t;
2553 }
2555 @Override
2556 public Type visitClassType(ClassType t, Void ignored) {
2557 Type outer1 = classBound(t.getEnclosingType());
2558 if (outer1 != t.getEnclosingType())
2559 return new ClassType(outer1, t.getTypeArguments(), t.tsym);
2560 else
2561 return t;
2562 }
2564 @Override
2565 public Type visitTypeVar(TypeVar t, Void ignored) {
2566 return classBound(supertype(t));
2567 }
2569 @Override
2570 public Type visitErrorType(ErrorType t, Void ignored) {
2571 return t;
2572 }
2573 };
2574 // </editor-fold>
2576 // <editor-fold defaultstate="collapsed" desc="sub signature / override equivalence">
2577 /**
2578 * Returns true iff the first signature is a <em>sub
2579 * signature</em> of the other. This is <b>not</b> an equivalence
2580 * relation.
2581 *
2582 * @jls section 8.4.2.
2583 * @see #overrideEquivalent(Type t, Type s)
2584 * @param t first signature (possibly raw).
2585 * @param s second signature (could be subjected to erasure).
2586 * @return true if t is a sub signature of s.
2587 */
2588 public boolean isSubSignature(Type t, Type s) {
2589 return isSubSignature(t, s, true);
2590 }
2592 public boolean isSubSignature(Type t, Type s, boolean strict) {
2593 return hasSameArgs(t, s, strict) || hasSameArgs(t, erasure(s), strict);
2594 }
2596 /**
2597 * Returns true iff these signatures are related by <em>override
2598 * equivalence</em>. This is the natural extension of
2599 * isSubSignature to an equivalence relation.
2600 *
2601 * @jls section 8.4.2.
2602 * @see #isSubSignature(Type t, Type s)
2603 * @param t a signature (possible raw, could be subjected to
2604 * erasure).
2605 * @param s a signature (possible raw, could be subjected to
2606 * erasure).
2607 * @return true if either argument is a sub signature of the other.
2608 */
2609 public boolean overrideEquivalent(Type t, Type s) {
2610 return hasSameArgs(t, s) ||
2611 hasSameArgs(t, erasure(s)) || hasSameArgs(erasure(t), s);
2612 }
2614 public boolean overridesObjectMethod(TypeSymbol origin, Symbol msym) {
2615 for (Scope.Entry e = syms.objectType.tsym.members().lookup(msym.name) ; e.scope != null ; e = e.next()) {
2616 if (msym.overrides(e.sym, origin, Types.this, true)) {
2617 return true;
2618 }
2619 }
2620 return false;
2621 }
2623 // <editor-fold defaultstate="collapsed" desc="Determining method implementation in given site">
2624 class ImplementationCache {
2626 private WeakHashMap<MethodSymbol, SoftReference<Map<TypeSymbol, Entry>>> _map =
2627 new WeakHashMap<MethodSymbol, SoftReference<Map<TypeSymbol, Entry>>>();
2629 class Entry {
2630 final MethodSymbol cachedImpl;
2631 final Filter<Symbol> implFilter;
2632 final boolean checkResult;
2633 final int prevMark;
2635 public Entry(MethodSymbol cachedImpl,
2636 Filter<Symbol> scopeFilter,
2637 boolean checkResult,
2638 int prevMark) {
2639 this.cachedImpl = cachedImpl;
2640 this.implFilter = scopeFilter;
2641 this.checkResult = checkResult;
2642 this.prevMark = prevMark;
2643 }
2645 boolean matches(Filter<Symbol> scopeFilter, boolean checkResult, int mark) {
2646 return this.implFilter == scopeFilter &&
2647 this.checkResult == checkResult &&
2648 this.prevMark == mark;
2649 }
2650 }
2652 MethodSymbol get(MethodSymbol ms, TypeSymbol origin, boolean checkResult, Filter<Symbol> implFilter) {
2653 SoftReference<Map<TypeSymbol, Entry>> ref_cache = _map.get(ms);
2654 Map<TypeSymbol, Entry> cache = ref_cache != null ? ref_cache.get() : null;
2655 if (cache == null) {
2656 cache = new HashMap<TypeSymbol, Entry>();
2657 _map.put(ms, new SoftReference<Map<TypeSymbol, Entry>>(cache));
2658 }
2659 Entry e = cache.get(origin);
2660 CompoundScope members = membersClosure(origin.type, true);
2661 if (e == null ||
2662 !e.matches(implFilter, checkResult, members.getMark())) {
2663 MethodSymbol impl = implementationInternal(ms, origin, checkResult, implFilter);
2664 cache.put(origin, new Entry(impl, implFilter, checkResult, members.getMark()));
2665 return impl;
2666 }
2667 else {
2668 return e.cachedImpl;
2669 }
2670 }
2672 private MethodSymbol implementationInternal(MethodSymbol ms, TypeSymbol origin, boolean checkResult, Filter<Symbol> implFilter) {
2673 for (Type t = origin.type; t.hasTag(CLASS) || t.hasTag(TYPEVAR); t = supertype(t)) {
2674 while (t.hasTag(TYPEVAR))
2675 t = t.getUpperBound();
2676 TypeSymbol c = t.tsym;
2677 for (Scope.Entry e = c.members().lookup(ms.name, implFilter);
2678 e.scope != null;
2679 e = e.next(implFilter)) {
2680 if (e.sym != null &&
2681 e.sym.overrides(ms, origin, Types.this, checkResult))
2682 return (MethodSymbol)e.sym;
2683 }
2684 }
2685 return null;
2686 }
2687 }
2689 private ImplementationCache implCache = new ImplementationCache();
2691 public MethodSymbol implementation(MethodSymbol ms, TypeSymbol origin, boolean checkResult, Filter<Symbol> implFilter) {
2692 return implCache.get(ms, origin, checkResult, implFilter);
2693 }
2694 // </editor-fold>
2696 // <editor-fold defaultstate="collapsed" desc="compute transitive closure of all members in given site">
2697 class MembersClosureCache extends SimpleVisitor<Scope.CompoundScope, Void> {
2699 private Map<TypeSymbol, CompoundScope> _map = new HashMap<>();
2701 Set<TypeSymbol> seenTypes = new HashSet<>();
2703 class MembersScope extends CompoundScope {
2705 CompoundScope scope;
2707 public MembersScope(CompoundScope scope) {
2708 super(scope.owner);
2709 this.scope = scope;
2710 }
2712 Filter<Symbol> combine(final Filter<Symbol> sf) {
2713 return new Filter<Symbol>() {
2714 @Override
2715 public boolean accepts(Symbol s) {
2716 return !s.owner.isInterface() && (sf == null || sf.accepts(s));
2717 }
2718 };
2719 }
2721 @Override
2722 public Iterable<Symbol> getElements(Filter<Symbol> sf) {
2723 return scope.getElements(combine(sf));
2724 }
2726 @Override
2727 public Iterable<Symbol> getElementsByName(Name name, Filter<Symbol> sf) {
2728 return scope.getElementsByName(name, combine(sf));
2729 }
2731 @Override
2732 public int getMark() {
2733 return scope.getMark();
2734 }
2735 }
2737 CompoundScope nilScope;
2739 /** members closure visitor methods **/
2741 public CompoundScope visitType(Type t, Void _unused) {
2742 if (nilScope == null) {
2743 nilScope = new CompoundScope(syms.noSymbol);
2744 }
2745 return nilScope;
2746 }
2748 @Override
2749 public CompoundScope visitClassType(ClassType t, Void _unused) {
2750 if (!seenTypes.add(t.tsym)) {
2751 //this is possible when an interface is implemented in multiple
2752 //superclasses, or when a class hierarchy is circular - in such
2753 //cases we don't need to recurse (empty scope is returned)
2754 return new CompoundScope(t.tsym);
2755 }
2756 try {
2757 seenTypes.add(t.tsym);
2758 ClassSymbol csym = (ClassSymbol)t.tsym;
2759 CompoundScope membersClosure = _map.get(csym);
2760 if (membersClosure == null) {
2761 membersClosure = new CompoundScope(csym);
2762 for (Type i : interfaces(t)) {
2763 membersClosure.addSubScope(visit(i, null));
2764 }
2765 membersClosure.addSubScope(visit(supertype(t), null));
2766 membersClosure.addSubScope(csym.members());
2767 _map.put(csym, membersClosure);
2768 }
2769 return membersClosure;
2770 }
2771 finally {
2772 seenTypes.remove(t.tsym);
2773 }
2774 }
2776 @Override
2777 public CompoundScope visitTypeVar(TypeVar t, Void _unused) {
2778 return visit(t.getUpperBound(), null);
2779 }
2780 }
2782 private MembersClosureCache membersCache = new MembersClosureCache();
2784 public CompoundScope membersClosure(Type site, boolean skipInterface) {
2785 CompoundScope cs = membersCache.visit(site, null);
2786 if (cs == null)
2787 Assert.error("type " + site);
2788 return skipInterface ? membersCache.new MembersScope(cs) : cs;
2789 }
2790 // </editor-fold>
2793 /** Return first abstract member of class `sym'.
2794 */
2795 public MethodSymbol firstUnimplementedAbstract(ClassSymbol sym) {
2796 try {
2797 return firstUnimplementedAbstractImpl(sym, sym);
2798 } catch (CompletionFailure ex) {
2799 chk.completionError(enter.getEnv(sym).tree.pos(), ex);
2800 return null;
2801 }
2802 }
2803 //where:
2804 private MethodSymbol firstUnimplementedAbstractImpl(ClassSymbol impl, ClassSymbol c) {
2805 MethodSymbol undef = null;
2806 // Do not bother to search in classes that are not abstract,
2807 // since they cannot have abstract members.
2808 if (c == impl || (c.flags() & (ABSTRACT | INTERFACE)) != 0) {
2809 Scope s = c.members();
2810 for (Scope.Entry e = s.elems;
2811 undef == null && e != null;
2812 e = e.sibling) {
2813 if (e.sym.kind == MTH &&
2814 (e.sym.flags() & (ABSTRACT|IPROXY|DEFAULT)) == ABSTRACT) {
2815 MethodSymbol absmeth = (MethodSymbol)e.sym;
2816 MethodSymbol implmeth = absmeth.implementation(impl, this, true);
2817 if (implmeth == null || implmeth == absmeth) {
2818 //look for default implementations
2819 if (allowDefaultMethods) {
2820 MethodSymbol prov = interfaceCandidates(impl.type, absmeth).head;
2821 if (prov != null && prov.overrides(absmeth, impl, this, true)) {
2822 implmeth = prov;
2823 }
2824 }
2825 }
2826 if (implmeth == null || implmeth == absmeth) {
2827 undef = absmeth;
2828 }
2829 }
2830 }
2831 if (undef == null) {
2832 Type st = supertype(c.type);
2833 if (st.hasTag(CLASS))
2834 undef = firstUnimplementedAbstractImpl(impl, (ClassSymbol)st.tsym);
2835 }
2836 for (List<Type> l = interfaces(c.type);
2837 undef == null && l.nonEmpty();
2838 l = l.tail) {
2839 undef = firstUnimplementedAbstractImpl(impl, (ClassSymbol)l.head.tsym);
2840 }
2841 }
2842 return undef;
2843 }
2846 //where
2847 public List<MethodSymbol> interfaceCandidates(Type site, MethodSymbol ms) {
2848 Filter<Symbol> filter = new MethodFilter(ms, site);
2849 List<MethodSymbol> candidates = List.nil();
2850 for (Symbol s : membersClosure(site, false).getElements(filter)) {
2851 if (!site.tsym.isInterface() && !s.owner.isInterface()) {
2852 return List.of((MethodSymbol)s);
2853 } else if (!candidates.contains(s)) {
2854 candidates = candidates.prepend((MethodSymbol)s);
2855 }
2856 }
2857 return prune(candidates);
2858 }
2860 public List<MethodSymbol> prune(List<MethodSymbol> methods) {
2861 ListBuffer<MethodSymbol> methodsMin = new ListBuffer<>();
2862 for (MethodSymbol m1 : methods) {
2863 boolean isMin_m1 = true;
2864 for (MethodSymbol m2 : methods) {
2865 if (m1 == m2) continue;
2866 if (m2.owner != m1.owner &&
2867 asSuper(m2.owner.type, m1.owner) != null) {
2868 isMin_m1 = false;
2869 break;
2870 }
2871 }
2872 if (isMin_m1)
2873 methodsMin.append(m1);
2874 }
2875 return methodsMin.toList();
2876 }
2877 // where
2878 private class MethodFilter implements Filter<Symbol> {
2880 Symbol msym;
2881 Type site;
2883 MethodFilter(Symbol msym, Type site) {
2884 this.msym = msym;
2885 this.site = site;
2886 }
2888 public boolean accepts(Symbol s) {
2889 return s.kind == Kinds.MTH &&
2890 s.name == msym.name &&
2891 (s.flags() & SYNTHETIC) == 0 &&
2892 s.isInheritedIn(site.tsym, Types.this) &&
2893 overrideEquivalent(memberType(site, s), memberType(site, msym));
2894 }
2895 };
2896 // </editor-fold>
2898 /**
2899 * Does t have the same arguments as s? It is assumed that both
2900 * types are (possibly polymorphic) method types. Monomorphic
2901 * method types "have the same arguments", if their argument lists
2902 * are equal. Polymorphic method types "have the same arguments",
2903 * if they have the same arguments after renaming all type
2904 * variables of one to corresponding type variables in the other,
2905 * where correspondence is by position in the type parameter list.
2906 */
2907 public boolean hasSameArgs(Type t, Type s) {
2908 return hasSameArgs(t, s, true);
2909 }
2911 public boolean hasSameArgs(Type t, Type s, boolean strict) {
2912 return hasSameArgs(t, s, strict ? hasSameArgs_strict : hasSameArgs_nonstrict);
2913 }
2915 private boolean hasSameArgs(Type t, Type s, TypeRelation hasSameArgs) {
2916 return hasSameArgs.visit(t, s);
2917 }
2918 // where
2919 private class HasSameArgs extends TypeRelation {
2921 boolean strict;
2923 public HasSameArgs(boolean strict) {
2924 this.strict = strict;
2925 }
2927 public Boolean visitType(Type t, Type s) {
2928 throw new AssertionError();
2929 }
2931 @Override
2932 public Boolean visitMethodType(MethodType t, Type s) {
2933 return s.hasTag(METHOD)
2934 && containsTypeEquivalent(t.argtypes, s.getParameterTypes());
2935 }
2937 @Override
2938 public Boolean visitForAll(ForAll t, Type s) {
2939 if (!s.hasTag(FORALL))
2940 return strict ? false : visitMethodType(t.asMethodType(), s);
2942 ForAll forAll = (ForAll)s;
2943 return hasSameBounds(t, forAll)
2944 && visit(t.qtype, subst(forAll.qtype, forAll.tvars, t.tvars));
2945 }
2947 @Override
2948 public Boolean visitErrorType(ErrorType t, Type s) {
2949 return false;
2950 }
2951 };
2953 TypeRelation hasSameArgs_strict = new HasSameArgs(true);
2954 TypeRelation hasSameArgs_nonstrict = new HasSameArgs(false);
2956 // </editor-fold>
2958 // <editor-fold defaultstate="collapsed" desc="subst">
2959 public List<Type> subst(List<Type> ts,
2960 List<Type> from,
2961 List<Type> to) {
2962 return new Subst(from, to).subst(ts);
2963 }
2965 /**
2966 * Substitute all occurrences of a type in `from' with the
2967 * corresponding type in `to' in 't'. Match lists `from' and `to'
2968 * from the right: If lists have different length, discard leading
2969 * elements of the longer list.
2970 */
2971 public Type subst(Type t, List<Type> from, List<Type> to) {
2972 return new Subst(from, to).subst(t);
2973 }
2975 private class Subst extends UnaryVisitor<Type> {
2976 List<Type> from;
2977 List<Type> to;
2979 public Subst(List<Type> from, List<Type> to) {
2980 int fromLength = from.length();
2981 int toLength = to.length();
2982 while (fromLength > toLength) {
2983 fromLength--;
2984 from = from.tail;
2985 }
2986 while (fromLength < toLength) {
2987 toLength--;
2988 to = to.tail;
2989 }
2990 this.from = from;
2991 this.to = to;
2992 }
2994 Type subst(Type t) {
2995 if (from.tail == null)
2996 return t;
2997 else
2998 return visit(t);
2999 }
3001 List<Type> subst(List<Type> ts) {
3002 if (from.tail == null)
3003 return ts;
3004 boolean wild = false;
3005 if (ts.nonEmpty() && from.nonEmpty()) {
3006 Type head1 = subst(ts.head);
3007 List<Type> tail1 = subst(ts.tail);
3008 if (head1 != ts.head || tail1 != ts.tail)
3009 return tail1.prepend(head1);
3010 }
3011 return ts;
3012 }
3014 public Type visitType(Type t, Void ignored) {
3015 return t;
3016 }
3018 @Override
3019 public Type visitMethodType(MethodType t, Void ignored) {
3020 List<Type> argtypes = subst(t.argtypes);
3021 Type restype = subst(t.restype);
3022 List<Type> thrown = subst(t.thrown);
3023 if (argtypes == t.argtypes &&
3024 restype == t.restype &&
3025 thrown == t.thrown)
3026 return t;
3027 else
3028 return new MethodType(argtypes, restype, thrown, t.tsym);
3029 }
3031 @Override
3032 public Type visitTypeVar(TypeVar t, Void ignored) {
3033 for (List<Type> from = this.from, to = this.to;
3034 from.nonEmpty();
3035 from = from.tail, to = to.tail) {
3036 if (t == from.head) {
3037 return to.head.withTypeVar(t);
3038 }
3039 }
3040 return t;
3041 }
3043 @Override
3044 public Type visitUndetVar(UndetVar t, Void ignored) {
3045 //do nothing - we should not replace inside undet variables
3046 return t;
3047 }
3049 @Override
3050 public Type visitClassType(ClassType t, Void ignored) {
3051 if (!t.isCompound()) {
3052 List<Type> typarams = t.getTypeArguments();
3053 List<Type> typarams1 = subst(typarams);
3054 Type outer = t.getEnclosingType();
3055 Type outer1 = subst(outer);
3056 if (typarams1 == typarams && outer1 == outer)
3057 return t;
3058 else
3059 return new ClassType(outer1, typarams1, t.tsym);
3060 } else {
3061 Type st = subst(supertype(t));
3062 List<Type> is = subst(interfaces(t));
3063 if (st == supertype(t) && is == interfaces(t))
3064 return t;
3065 else
3066 return makeCompoundType(is.prepend(st));
3067 }
3068 }
3070 @Override
3071 public Type visitWildcardType(WildcardType t, Void ignored) {
3072 Type bound = t.type;
3073 if (t.kind != BoundKind.UNBOUND)
3074 bound = subst(bound);
3075 if (bound == t.type) {
3076 return t;
3077 } else {
3078 if (t.isExtendsBound() && bound.isExtendsBound())
3079 bound = wildUpperBound(bound);
3080 return new WildcardType(bound, t.kind, syms.boundClass, t.bound);
3081 }
3082 }
3084 @Override
3085 public Type visitArrayType(ArrayType t, Void ignored) {
3086 Type elemtype = subst(t.elemtype);
3087 if (elemtype == t.elemtype)
3088 return t;
3089 else
3090 return new ArrayType(elemtype, t.tsym);
3091 }
3093 @Override
3094 public Type visitForAll(ForAll t, Void ignored) {
3095 if (Type.containsAny(to, t.tvars)) {
3096 //perform alpha-renaming of free-variables in 't'
3097 //if 'to' types contain variables that are free in 't'
3098 List<Type> freevars = newInstances(t.tvars);
3099 t = new ForAll(freevars,
3100 Types.this.subst(t.qtype, t.tvars, freevars));
3101 }
3102 List<Type> tvars1 = substBounds(t.tvars, from, to);
3103 Type qtype1 = subst(t.qtype);
3104 if (tvars1 == t.tvars && qtype1 == t.qtype) {
3105 return t;
3106 } else if (tvars1 == t.tvars) {
3107 return new ForAll(tvars1, qtype1);
3108 } else {
3109 return new ForAll(tvars1, Types.this.subst(qtype1, t.tvars, tvars1));
3110 }
3111 }
3113 @Override
3114 public Type visitErrorType(ErrorType t, Void ignored) {
3115 return t;
3116 }
3117 }
3119 public List<Type> substBounds(List<Type> tvars,
3120 List<Type> from,
3121 List<Type> to) {
3122 if (tvars.isEmpty())
3123 return tvars;
3124 ListBuffer<Type> newBoundsBuf = new ListBuffer<>();
3125 boolean changed = false;
3126 // calculate new bounds
3127 for (Type t : tvars) {
3128 TypeVar tv = (TypeVar) t;
3129 Type bound = subst(tv.bound, from, to);
3130 if (bound != tv.bound)
3131 changed = true;
3132 newBoundsBuf.append(bound);
3133 }
3134 if (!changed)
3135 return tvars;
3136 ListBuffer<Type> newTvars = new ListBuffer<>();
3137 // create new type variables without bounds
3138 for (Type t : tvars) {
3139 newTvars.append(new TypeVar(t.tsym, null, syms.botType));
3140 }
3141 // the new bounds should use the new type variables in place
3142 // of the old
3143 List<Type> newBounds = newBoundsBuf.toList();
3144 from = tvars;
3145 to = newTvars.toList();
3146 for (; !newBounds.isEmpty(); newBounds = newBounds.tail) {
3147 newBounds.head = subst(newBounds.head, from, to);
3148 }
3149 newBounds = newBoundsBuf.toList();
3150 // set the bounds of new type variables to the new bounds
3151 for (Type t : newTvars.toList()) {
3152 TypeVar tv = (TypeVar) t;
3153 tv.bound = newBounds.head;
3154 newBounds = newBounds.tail;
3155 }
3156 return newTvars.toList();
3157 }
3159 public TypeVar substBound(TypeVar t, List<Type> from, List<Type> to) {
3160 Type bound1 = subst(t.bound, from, to);
3161 if (bound1 == t.bound)
3162 return t;
3163 else {
3164 // create new type variable without bounds
3165 TypeVar tv = new TypeVar(t.tsym, null, syms.botType);
3166 // the new bound should use the new type variable in place
3167 // of the old
3168 tv.bound = subst(bound1, List.<Type>of(t), List.<Type>of(tv));
3169 return tv;
3170 }
3171 }
3172 // </editor-fold>
3174 // <editor-fold defaultstate="collapsed" desc="hasSameBounds">
3175 /**
3176 * Does t have the same bounds for quantified variables as s?
3177 */
3178 public boolean hasSameBounds(ForAll t, ForAll s) {
3179 List<Type> l1 = t.tvars;
3180 List<Type> l2 = s.tvars;
3181 while (l1.nonEmpty() && l2.nonEmpty() &&
3182 isSameType(l1.head.getUpperBound(),
3183 subst(l2.head.getUpperBound(),
3184 s.tvars,
3185 t.tvars))) {
3186 l1 = l1.tail;
3187 l2 = l2.tail;
3188 }
3189 return l1.isEmpty() && l2.isEmpty();
3190 }
3191 // </editor-fold>
3193 // <editor-fold defaultstate="collapsed" desc="newInstances">
3194 /** Create new vector of type variables from list of variables
3195 * changing all recursive bounds from old to new list.
3196 */
3197 public List<Type> newInstances(List<Type> tvars) {
3198 List<Type> tvars1 = Type.map(tvars, newInstanceFun);
3199 for (List<Type> l = tvars1; l.nonEmpty(); l = l.tail) {
3200 TypeVar tv = (TypeVar) l.head;
3201 tv.bound = subst(tv.bound, tvars, tvars1);
3202 }
3203 return tvars1;
3204 }
3205 private static final Mapping newInstanceFun = new Mapping("newInstanceFun") {
3206 public Type apply(Type t) { return new TypeVar(t.tsym, t.getUpperBound(), t.getLowerBound()); }
3207 };
3208 // </editor-fold>
3210 public Type createMethodTypeWithParameters(Type original, List<Type> newParams) {
3211 return original.accept(methodWithParameters, newParams);
3212 }
3213 // where
3214 private final MapVisitor<List<Type>> methodWithParameters = new MapVisitor<List<Type>>() {
3215 public Type visitType(Type t, List<Type> newParams) {
3216 throw new IllegalArgumentException("Not a method type: " + t);
3217 }
3218 public Type visitMethodType(MethodType t, List<Type> newParams) {
3219 return new MethodType(newParams, t.restype, t.thrown, t.tsym);
3220 }
3221 public Type visitForAll(ForAll t, List<Type> newParams) {
3222 return new ForAll(t.tvars, t.qtype.accept(this, newParams));
3223 }
3224 };
3226 public Type createMethodTypeWithThrown(Type original, List<Type> newThrown) {
3227 return original.accept(methodWithThrown, newThrown);
3228 }
3229 // where
3230 private final MapVisitor<List<Type>> methodWithThrown = new MapVisitor<List<Type>>() {
3231 public Type visitType(Type t, List<Type> newThrown) {
3232 throw new IllegalArgumentException("Not a method type: " + t);
3233 }
3234 public Type visitMethodType(MethodType t, List<Type> newThrown) {
3235 return new MethodType(t.argtypes, t.restype, newThrown, t.tsym);
3236 }
3237 public Type visitForAll(ForAll t, List<Type> newThrown) {
3238 return new ForAll(t.tvars, t.qtype.accept(this, newThrown));
3239 }
3240 };
3242 public Type createMethodTypeWithReturn(Type original, Type newReturn) {
3243 return original.accept(methodWithReturn, newReturn);
3244 }
3245 // where
3246 private final MapVisitor<Type> methodWithReturn = new MapVisitor<Type>() {
3247 public Type visitType(Type t, Type newReturn) {
3248 throw new IllegalArgumentException("Not a method type: " + t);
3249 }
3250 public Type visitMethodType(MethodType t, Type newReturn) {
3251 return new MethodType(t.argtypes, newReturn, t.thrown, t.tsym);
3252 }
3253 public Type visitForAll(ForAll t, Type newReturn) {
3254 return new ForAll(t.tvars, t.qtype.accept(this, newReturn));
3255 }
3256 };
3258 // <editor-fold defaultstate="collapsed" desc="createErrorType">
3259 public Type createErrorType(Type originalType) {
3260 return new ErrorType(originalType, syms.errSymbol);
3261 }
3263 public Type createErrorType(ClassSymbol c, Type originalType) {
3264 return new ErrorType(c, originalType);
3265 }
3267 public Type createErrorType(Name name, TypeSymbol container, Type originalType) {
3268 return new ErrorType(name, container, originalType);
3269 }
3270 // </editor-fold>
3272 // <editor-fold defaultstate="collapsed" desc="rank">
3273 /**
3274 * The rank of a class is the length of the longest path between
3275 * the class and java.lang.Object in the class inheritance
3276 * graph. Undefined for all but reference types.
3277 */
3278 public int rank(Type t) {
3279 t = t.unannotatedType();
3280 switch(t.getTag()) {
3281 case CLASS: {
3282 ClassType cls = (ClassType)t;
3283 if (cls.rank_field < 0) {
3284 Name fullname = cls.tsym.getQualifiedName();
3285 if (fullname == names.java_lang_Object)
3286 cls.rank_field = 0;
3287 else {
3288 int r = rank(supertype(cls));
3289 for (List<Type> l = interfaces(cls);
3290 l.nonEmpty();
3291 l = l.tail) {
3292 if (rank(l.head) > r)
3293 r = rank(l.head);
3294 }
3295 cls.rank_field = r + 1;
3296 }
3297 }
3298 return cls.rank_field;
3299 }
3300 case TYPEVAR: {
3301 TypeVar tvar = (TypeVar)t;
3302 if (tvar.rank_field < 0) {
3303 int r = rank(supertype(tvar));
3304 for (List<Type> l = interfaces(tvar);
3305 l.nonEmpty();
3306 l = l.tail) {
3307 if (rank(l.head) > r) r = rank(l.head);
3308 }
3309 tvar.rank_field = r + 1;
3310 }
3311 return tvar.rank_field;
3312 }
3313 case ERROR:
3314 case NONE:
3315 return 0;
3316 default:
3317 throw new AssertionError();
3318 }
3319 }
3320 // </editor-fold>
3322 /**
3323 * Helper method for generating a string representation of a given type
3324 * accordingly to a given locale
3325 */
3326 public String toString(Type t, Locale locale) {
3327 return Printer.createStandardPrinter(messages).visit(t, locale);
3328 }
3330 /**
3331 * Helper method for generating a string representation of a given type
3332 * accordingly to a given locale
3333 */
3334 public String toString(Symbol t, Locale locale) {
3335 return Printer.createStandardPrinter(messages).visit(t, locale);
3336 }
3338 // <editor-fold defaultstate="collapsed" desc="toString">
3339 /**
3340 * This toString is slightly more descriptive than the one on Type.
3341 *
3342 * @deprecated Types.toString(Type t, Locale l) provides better support
3343 * for localization
3344 */
3345 @Deprecated
3346 public String toString(Type t) {
3347 if (t.hasTag(FORALL)) {
3348 ForAll forAll = (ForAll)t;
3349 return typaramsString(forAll.tvars) + forAll.qtype;
3350 }
3351 return "" + t;
3352 }
3353 // where
3354 private String typaramsString(List<Type> tvars) {
3355 StringBuilder s = new StringBuilder();
3356 s.append('<');
3357 boolean first = true;
3358 for (Type t : tvars) {
3359 if (!first) s.append(", ");
3360 first = false;
3361 appendTyparamString(((TypeVar)t.unannotatedType()), s);
3362 }
3363 s.append('>');
3364 return s.toString();
3365 }
3366 private void appendTyparamString(TypeVar t, StringBuilder buf) {
3367 buf.append(t);
3368 if (t.bound == null ||
3369 t.bound.tsym.getQualifiedName() == names.java_lang_Object)
3370 return;
3371 buf.append(" extends "); // Java syntax; no need for i18n
3372 Type bound = t.bound;
3373 if (!bound.isCompound()) {
3374 buf.append(bound);
3375 } else if ((erasure(t).tsym.flags() & INTERFACE) == 0) {
3376 buf.append(supertype(t));
3377 for (Type intf : interfaces(t)) {
3378 buf.append('&');
3379 buf.append(intf);
3380 }
3381 } else {
3382 // No superclass was given in bounds.
3383 // In this case, supertype is Object, erasure is first interface.
3384 boolean first = true;
3385 for (Type intf : interfaces(t)) {
3386 if (!first) buf.append('&');
3387 first = false;
3388 buf.append(intf);
3389 }
3390 }
3391 }
3392 // </editor-fold>
3394 // <editor-fold defaultstate="collapsed" desc="Determining least upper bounds of types">
3395 /**
3396 * A cache for closures.
3397 *
3398 * <p>A closure is a list of all the supertypes and interfaces of
3399 * a class or interface type, ordered by ClassSymbol.precedes
3400 * (that is, subclasses come first, arbitrary but fixed
3401 * otherwise).
3402 */
3403 private Map<Type,List<Type>> closureCache = new HashMap<Type,List<Type>>();
3405 /**
3406 * Returns the closure of a class or interface type.
3407 */
3408 public List<Type> closure(Type t) {
3409 List<Type> cl = closureCache.get(t);
3410 if (cl == null) {
3411 Type st = supertype(t);
3412 if (!t.isCompound()) {
3413 if (st.hasTag(CLASS)) {
3414 cl = insert(closure(st), t);
3415 } else if (st.hasTag(TYPEVAR)) {
3416 cl = closure(st).prepend(t);
3417 } else {
3418 cl = List.of(t);
3419 }
3420 } else {
3421 cl = closure(supertype(t));
3422 }
3423 for (List<Type> l = interfaces(t); l.nonEmpty(); l = l.tail)
3424 cl = union(cl, closure(l.head));
3425 closureCache.put(t, cl);
3426 }
3427 return cl;
3428 }
3430 /**
3431 * Insert a type in a closure
3432 */
3433 public List<Type> insert(List<Type> cl, Type t) {
3434 if (cl.isEmpty()) {
3435 return cl.prepend(t);
3436 } else if (t.tsym == cl.head.tsym) {
3437 return cl;
3438 } else if (t.tsym.precedes(cl.head.tsym, this)) {
3439 return cl.prepend(t);
3440 } else {
3441 // t comes after head, or the two are unrelated
3442 return insert(cl.tail, t).prepend(cl.head);
3443 }
3444 }
3446 /**
3447 * Form the union of two closures
3448 */
3449 public List<Type> union(List<Type> cl1, List<Type> cl2) {
3450 if (cl1.isEmpty()) {
3451 return cl2;
3452 } else if (cl2.isEmpty()) {
3453 return cl1;
3454 } else if (cl1.head.tsym == cl2.head.tsym) {
3455 return union(cl1.tail, cl2.tail).prepend(cl1.head);
3456 } else if (cl1.head.tsym.precedes(cl2.head.tsym, this)) {
3457 return union(cl1.tail, cl2).prepend(cl1.head);
3458 } else if (cl2.head.tsym.precedes(cl1.head.tsym, this)) {
3459 return union(cl1, cl2.tail).prepend(cl2.head);
3460 } else {
3461 // unrelated types
3462 return union(cl1.tail, cl2).prepend(cl1.head);
3463 }
3464 }
3466 /**
3467 * Intersect two closures
3468 */
3469 public List<Type> intersect(List<Type> cl1, List<Type> cl2) {
3470 if (cl1 == cl2)
3471 return cl1;
3472 if (cl1.isEmpty() || cl2.isEmpty())
3473 return List.nil();
3474 if (cl1.head.tsym.precedes(cl2.head.tsym, this))
3475 return intersect(cl1.tail, cl2);
3476 if (cl2.head.tsym.precedes(cl1.head.tsym, this))
3477 return intersect(cl1, cl2.tail);
3478 if (isSameType(cl1.head, cl2.head))
3479 return intersect(cl1.tail, cl2.tail).prepend(cl1.head);
3480 if (cl1.head.tsym == cl2.head.tsym &&
3481 cl1.head.hasTag(CLASS) && cl2.head.hasTag(CLASS)) {
3482 if (cl1.head.isParameterized() && cl2.head.isParameterized()) {
3483 Type merge = merge(cl1.head,cl2.head);
3484 return intersect(cl1.tail, cl2.tail).prepend(merge);
3485 }
3486 if (cl1.head.isRaw() || cl2.head.isRaw())
3487 return intersect(cl1.tail, cl2.tail).prepend(erasure(cl1.head));
3488 }
3489 return intersect(cl1.tail, cl2.tail);
3490 }
3491 // where
3492 class TypePair {
3493 final Type t1;
3494 final Type t2;
3495 boolean strict;
3497 TypePair(Type t1, Type t2) {
3498 this(t1, t2, false);
3499 }
3501 TypePair(Type t1, Type t2, boolean strict) {
3502 this.t1 = t1;
3503 this.t2 = t2;
3504 this.strict = strict;
3505 }
3506 @Override
3507 public int hashCode() {
3508 return 127 * Types.this.hashCode(t1) + Types.this.hashCode(t2);
3509 }
3510 @Override
3511 public boolean equals(Object obj) {
3512 if (!(obj instanceof TypePair))
3513 return false;
3514 TypePair typePair = (TypePair)obj;
3515 return isSameType(t1, typePair.t1, strict)
3516 && isSameType(t2, typePair.t2, strict);
3517 }
3518 }
3519 Set<TypePair> mergeCache = new HashSet<TypePair>();
3520 private Type merge(Type c1, Type c2) {
3521 ClassType class1 = (ClassType) c1;
3522 List<Type> act1 = class1.getTypeArguments();
3523 ClassType class2 = (ClassType) c2;
3524 List<Type> act2 = class2.getTypeArguments();
3525 ListBuffer<Type> merged = new ListBuffer<Type>();
3526 List<Type> typarams = class1.tsym.type.getTypeArguments();
3528 while (act1.nonEmpty() && act2.nonEmpty() && typarams.nonEmpty()) {
3529 if (containsType(act1.head, act2.head)) {
3530 merged.append(act1.head);
3531 } else if (containsType(act2.head, act1.head)) {
3532 merged.append(act2.head);
3533 } else {
3534 TypePair pair = new TypePair(c1, c2);
3535 Type m;
3536 if (mergeCache.add(pair)) {
3537 m = new WildcardType(lub(wildUpperBound(act1.head),
3538 wildUpperBound(act2.head)),
3539 BoundKind.EXTENDS,
3540 syms.boundClass);
3541 mergeCache.remove(pair);
3542 } else {
3543 m = new WildcardType(syms.objectType,
3544 BoundKind.UNBOUND,
3545 syms.boundClass);
3546 }
3547 merged.append(m.withTypeVar(typarams.head));
3548 }
3549 act1 = act1.tail;
3550 act2 = act2.tail;
3551 typarams = typarams.tail;
3552 }
3553 Assert.check(act1.isEmpty() && act2.isEmpty() && typarams.isEmpty());
3554 return new ClassType(class1.getEnclosingType(), merged.toList(), class1.tsym);
3555 }
3557 /**
3558 * Return the minimum type of a closure, a compound type if no
3559 * unique minimum exists.
3560 */
3561 private Type compoundMin(List<Type> cl) {
3562 if (cl.isEmpty()) return syms.objectType;
3563 List<Type> compound = closureMin(cl);
3564 if (compound.isEmpty())
3565 return null;
3566 else if (compound.tail.isEmpty())
3567 return compound.head;
3568 else
3569 return makeCompoundType(compound);
3570 }
3572 /**
3573 * Return the minimum types of a closure, suitable for computing
3574 * compoundMin or glb.
3575 */
3576 private List<Type> closureMin(List<Type> cl) {
3577 ListBuffer<Type> classes = new ListBuffer<>();
3578 ListBuffer<Type> interfaces = new ListBuffer<>();
3579 Set<Type> toSkip = new HashSet<>();
3580 while (!cl.isEmpty()) {
3581 Type current = cl.head;
3582 boolean keep = !toSkip.contains(current);
3583 if (keep && current.hasTag(TYPEVAR)) {
3584 // skip lower-bounded variables with a subtype in cl.tail
3585 for (Type t : cl.tail) {
3586 if (isSubtypeNoCapture(t, current)) {
3587 keep = false;
3588 break;
3589 }
3590 }
3591 }
3592 if (keep) {
3593 if (current.isInterface())
3594 interfaces.append(current);
3595 else
3596 classes.append(current);
3597 for (Type t : cl.tail) {
3598 // skip supertypes of 'current' in cl.tail
3599 if (isSubtypeNoCapture(current, t))
3600 toSkip.add(t);
3601 }
3602 }
3603 cl = cl.tail;
3604 }
3605 return classes.appendList(interfaces).toList();
3606 }
3608 /**
3609 * Return the least upper bound of list of types. if the lub does
3610 * not exist return null.
3611 */
3612 public Type lub(List<Type> ts) {
3613 return lub(ts.toArray(new Type[ts.length()]));
3614 }
3616 /**
3617 * Return the least upper bound (lub) of set of types. If the lub
3618 * does not exist return the type of null (bottom).
3619 */
3620 public Type lub(Type... ts) {
3621 final int UNKNOWN_BOUND = 0;
3622 final int ARRAY_BOUND = 1;
3623 final int CLASS_BOUND = 2;
3625 int[] kinds = new int[ts.length];
3627 int boundkind = UNKNOWN_BOUND;
3628 for (int i = 0 ; i < ts.length ; i++) {
3629 Type t = ts[i];
3630 switch (t.getTag()) {
3631 case CLASS:
3632 boundkind |= kinds[i] = CLASS_BOUND;
3633 break;
3634 case ARRAY:
3635 boundkind |= kinds[i] = ARRAY_BOUND;
3636 break;
3637 case TYPEVAR:
3638 do {
3639 t = t.getUpperBound();
3640 } while (t.hasTag(TYPEVAR));
3641 if (t.hasTag(ARRAY)) {
3642 boundkind |= kinds[i] = ARRAY_BOUND;
3643 } else {
3644 boundkind |= kinds[i] = CLASS_BOUND;
3645 }
3646 break;
3647 default:
3648 kinds[i] = UNKNOWN_BOUND;
3649 if (t.isPrimitive())
3650 return syms.errType;
3651 }
3652 }
3653 switch (boundkind) {
3654 case 0:
3655 return syms.botType;
3657 case ARRAY_BOUND:
3658 // calculate lub(A[], B[])
3659 Type[] elements = new Type[ts.length];
3660 for (int i = 0 ; i < ts.length ; i++) {
3661 Type elem = elements[i] = elemTypeFun.apply(ts[i]);
3662 if (elem.isPrimitive()) {
3663 // if a primitive type is found, then return
3664 // arraySuperType unless all the types are the
3665 // same
3666 Type first = ts[0];
3667 for (int j = 1 ; j < ts.length ; j++) {
3668 if (!isSameType(first, ts[j])) {
3669 // lub(int[], B[]) is Cloneable & Serializable
3670 return arraySuperType();
3671 }
3672 }
3673 // all the array types are the same, return one
3674 // lub(int[], int[]) is int[]
3675 return first;
3676 }
3677 }
3678 // lub(A[], B[]) is lub(A, B)[]
3679 return new ArrayType(lub(elements), syms.arrayClass);
3681 case CLASS_BOUND:
3682 // calculate lub(A, B)
3683 int startIdx = 0;
3684 for (int i = 0; i < ts.length ; i++) {
3685 Type t = ts[i];
3686 if (t.hasTag(CLASS) || t.hasTag(TYPEVAR)) {
3687 break;
3688 } else {
3689 startIdx++;
3690 }
3691 }
3692 Assert.check(startIdx < ts.length);
3693 //step 1 - compute erased candidate set (EC)
3694 List<Type> cl = erasedSupertypes(ts[startIdx]);
3695 for (int i = startIdx + 1 ; i < ts.length ; i++) {
3696 Type t = ts[i];
3697 if (t.hasTag(CLASS) || t.hasTag(TYPEVAR))
3698 cl = intersect(cl, erasedSupertypes(t));
3699 }
3700 //step 2 - compute minimal erased candidate set (MEC)
3701 List<Type> mec = closureMin(cl);
3702 //step 3 - for each element G in MEC, compute lci(Inv(G))
3703 List<Type> candidates = List.nil();
3704 for (Type erasedSupertype : mec) {
3705 List<Type> lci = List.of(asSuper(ts[startIdx], erasedSupertype.tsym));
3706 for (int i = startIdx + 1 ; i < ts.length ; i++) {
3707 Type superType = asSuper(ts[i], erasedSupertype.tsym);
3708 lci = intersect(lci, superType != null ? List.of(superType) : List.<Type>nil());
3709 }
3710 candidates = candidates.appendList(lci);
3711 }
3712 //step 4 - let MEC be { G1, G2 ... Gn }, then we have that
3713 //lub = lci(Inv(G1)) & lci(Inv(G2)) & ... & lci(Inv(Gn))
3714 return compoundMin(candidates);
3716 default:
3717 // calculate lub(A, B[])
3718 List<Type> classes = List.of(arraySuperType());
3719 for (int i = 0 ; i < ts.length ; i++) {
3720 if (kinds[i] != ARRAY_BOUND) // Filter out any arrays
3721 classes = classes.prepend(ts[i]);
3722 }
3723 // lub(A, B[]) is lub(A, arraySuperType)
3724 return lub(classes);
3725 }
3726 }
3727 // where
3728 List<Type> erasedSupertypes(Type t) {
3729 ListBuffer<Type> buf = new ListBuffer<>();
3730 for (Type sup : closure(t)) {
3731 if (sup.hasTag(TYPEVAR)) {
3732 buf.append(sup);
3733 } else {
3734 buf.append(erasure(sup));
3735 }
3736 }
3737 return buf.toList();
3738 }
3740 private Type arraySuperType = null;
3741 private Type arraySuperType() {
3742 // initialized lazily to avoid problems during compiler startup
3743 if (arraySuperType == null) {
3744 synchronized (this) {
3745 if (arraySuperType == null) {
3746 // JLS 10.8: all arrays implement Cloneable and Serializable.
3747 arraySuperType = makeCompoundType(List.of(syms.serializableType,
3748 syms.cloneableType), true);
3749 }
3750 }
3751 }
3752 return arraySuperType;
3753 }
3754 // </editor-fold>
3756 // <editor-fold defaultstate="collapsed" desc="Greatest lower bound">
3757 public Type glb(List<Type> ts) {
3758 Type t1 = ts.head;
3759 for (Type t2 : ts.tail) {
3760 if (t1.isErroneous())
3761 return t1;
3762 t1 = glb(t1, t2);
3763 }
3764 return t1;
3765 }
3766 //where
3767 public Type glb(Type t, Type s) {
3768 if (s == null)
3769 return t;
3770 else if (t.isPrimitive() || s.isPrimitive())
3771 return syms.errType;
3772 else if (isSubtypeNoCapture(t, s))
3773 return t;
3774 else if (isSubtypeNoCapture(s, t))
3775 return s;
3777 List<Type> closure = union(closure(t), closure(s));
3778 return glbFlattened(closure, t);
3779 }
3780 //where
3781 /**
3782 * Perform glb for a list of non-primitive, non-error, non-compound types;
3783 * redundant elements are removed. Bounds should be ordered according to
3784 * {@link Symbol#precedes(TypeSymbol,Types)}.
3785 *
3786 * @param flatBounds List of type to glb
3787 * @param errT Original type to use if the result is an error type
3788 */
3789 private Type glbFlattened(List<Type> flatBounds, Type errT) {
3790 List<Type> bounds = closureMin(flatBounds);
3792 if (bounds.isEmpty()) { // length == 0
3793 return syms.objectType;
3794 } else if (bounds.tail.isEmpty()) { // length == 1
3795 return bounds.head;
3796 } else { // length > 1
3797 int classCount = 0;
3798 List<Type> lowers = List.nil();
3799 for (Type bound : bounds) {
3800 if (!bound.isInterface()) {
3801 classCount++;
3802 Type lower = cvarLowerBound(bound);
3803 if (bound != lower && !lower.hasTag(BOT))
3804 lowers = insert(lowers, lower);
3805 }
3806 }
3807 if (classCount > 1) {
3808 if (lowers.isEmpty())
3809 return createErrorType(errT);
3810 else
3811 return glbFlattened(union(bounds, lowers), errT);
3812 }
3813 }
3814 return makeCompoundType(bounds);
3815 }
3816 // </editor-fold>
3818 // <editor-fold defaultstate="collapsed" desc="hashCode">
3819 /**
3820 * Compute a hash code on a type.
3821 */
3822 public int hashCode(Type t) {
3823 return hashCode.visit(t);
3824 }
3825 // where
3826 private static final UnaryVisitor<Integer> hashCode = new UnaryVisitor<Integer>() {
3828 public Integer visitType(Type t, Void ignored) {
3829 return t.getTag().ordinal();
3830 }
3832 @Override
3833 public Integer visitClassType(ClassType t, Void ignored) {
3834 int result = visit(t.getEnclosingType());
3835 result *= 127;
3836 result += t.tsym.flatName().hashCode();
3837 for (Type s : t.getTypeArguments()) {
3838 result *= 127;
3839 result += visit(s);
3840 }
3841 return result;
3842 }
3844 @Override
3845 public Integer visitMethodType(MethodType t, Void ignored) {
3846 int h = METHOD.ordinal();
3847 for (List<Type> thisargs = t.argtypes;
3848 thisargs.tail != null;
3849 thisargs = thisargs.tail)
3850 h = (h << 5) + visit(thisargs.head);
3851 return (h << 5) + visit(t.restype);
3852 }
3854 @Override
3855 public Integer visitWildcardType(WildcardType t, Void ignored) {
3856 int result = t.kind.hashCode();
3857 if (t.type != null) {
3858 result *= 127;
3859 result += visit(t.type);
3860 }
3861 return result;
3862 }
3864 @Override
3865 public Integer visitArrayType(ArrayType t, Void ignored) {
3866 return visit(t.elemtype) + 12;
3867 }
3869 @Override
3870 public Integer visitTypeVar(TypeVar t, Void ignored) {
3871 return System.identityHashCode(t.tsym);
3872 }
3874 @Override
3875 public Integer visitUndetVar(UndetVar t, Void ignored) {
3876 return System.identityHashCode(t);
3877 }
3879 @Override
3880 public Integer visitErrorType(ErrorType t, Void ignored) {
3881 return 0;
3882 }
3883 };
3884 // </editor-fold>
3886 // <editor-fold defaultstate="collapsed" desc="Return-Type-Substitutable">
3887 /**
3888 * Does t have a result that is a subtype of the result type of s,
3889 * suitable for covariant returns? It is assumed that both types
3890 * are (possibly polymorphic) method types. Monomorphic method
3891 * types are handled in the obvious way. Polymorphic method types
3892 * require renaming all type variables of one to corresponding
3893 * type variables in the other, where correspondence is by
3894 * position in the type parameter list. */
3895 public boolean resultSubtype(Type t, Type s, Warner warner) {
3896 List<Type> tvars = t.getTypeArguments();
3897 List<Type> svars = s.getTypeArguments();
3898 Type tres = t.getReturnType();
3899 Type sres = subst(s.getReturnType(), svars, tvars);
3900 return covariantReturnType(tres, sres, warner);
3901 }
3903 /**
3904 * Return-Type-Substitutable.
3905 * @jls section 8.4.5
3906 */
3907 public boolean returnTypeSubstitutable(Type r1, Type r2) {
3908 if (hasSameArgs(r1, r2))
3909 return resultSubtype(r1, r2, noWarnings);
3910 else
3911 return covariantReturnType(r1.getReturnType(),
3912 erasure(r2.getReturnType()),
3913 noWarnings);
3914 }
3916 public boolean returnTypeSubstitutable(Type r1,
3917 Type r2, Type r2res,
3918 Warner warner) {
3919 if (isSameType(r1.getReturnType(), r2res))
3920 return true;
3921 if (r1.getReturnType().isPrimitive() || r2res.isPrimitive())
3922 return false;
3924 if (hasSameArgs(r1, r2))
3925 return covariantReturnType(r1.getReturnType(), r2res, warner);
3926 if (!allowCovariantReturns)
3927 return false;
3928 if (isSubtypeUnchecked(r1.getReturnType(), r2res, warner))
3929 return true;
3930 if (!isSubtype(r1.getReturnType(), erasure(r2res)))
3931 return false;
3932 warner.warn(LintCategory.UNCHECKED);
3933 return true;
3934 }
3936 /**
3937 * Is t an appropriate return type in an overrider for a
3938 * method that returns s?
3939 */
3940 public boolean covariantReturnType(Type t, Type s, Warner warner) {
3941 return
3942 isSameType(t, s) ||
3943 allowCovariantReturns &&
3944 !t.isPrimitive() &&
3945 !s.isPrimitive() &&
3946 isAssignable(t, s, warner);
3947 }
3948 // </editor-fold>
3950 // <editor-fold defaultstate="collapsed" desc="Box/unbox support">
3951 /**
3952 * Return the class that boxes the given primitive.
3953 */
3954 public ClassSymbol boxedClass(Type t) {
3955 return reader.enterClass(syms.boxedName[t.getTag().ordinal()]);
3956 }
3958 /**
3959 * Return the boxed type if 't' is primitive, otherwise return 't' itself.
3960 */
3961 public Type boxedTypeOrType(Type t) {
3962 return t.isPrimitive() ?
3963 boxedClass(t).type :
3964 t;
3965 }
3967 /**
3968 * Return the primitive type corresponding to a boxed type.
3969 */
3970 public Type unboxedType(Type t) {
3971 if (allowBoxing) {
3972 for (int i=0; i<syms.boxedName.length; i++) {
3973 Name box = syms.boxedName[i];
3974 if (box != null &&
3975 asSuper(t, reader.enterClass(box)) != null)
3976 return syms.typeOfTag[i];
3977 }
3978 }
3979 return Type.noType;
3980 }
3982 /**
3983 * Return the unboxed type if 't' is a boxed class, otherwise return 't' itself.
3984 */
3985 public Type unboxedTypeOrType(Type t) {
3986 Type unboxedType = unboxedType(t);
3987 return unboxedType.hasTag(NONE) ? t : unboxedType;
3988 }
3989 // </editor-fold>
3991 // <editor-fold defaultstate="collapsed" desc="Capture conversion">
3992 /*
3993 * JLS 5.1.10 Capture Conversion:
3994 *
3995 * Let G name a generic type declaration with n formal type
3996 * parameters A1 ... An with corresponding bounds U1 ... Un. There
3997 * exists a capture conversion from G<T1 ... Tn> to G<S1 ... Sn>,
3998 * where, for 1 <= i <= n:
3999 *
4000 * + If Ti is a wildcard type argument (4.5.1) of the form ? then
4001 * Si is a fresh type variable whose upper bound is
4002 * Ui[A1 := S1, ..., An := Sn] and whose lower bound is the null
4003 * type.
4004 *
4005 * + If Ti is a wildcard type argument of the form ? extends Bi,
4006 * then Si is a fresh type variable whose upper bound is
4007 * glb(Bi, Ui[A1 := S1, ..., An := Sn]) and whose lower bound is
4008 * the null type, where glb(V1,... ,Vm) is V1 & ... & Vm. It is
4009 * a compile-time error if for any two classes (not interfaces)
4010 * Vi and Vj,Vi is not a subclass of Vj or vice versa.
4011 *
4012 * + If Ti is a wildcard type argument of the form ? super Bi,
4013 * then Si is a fresh type variable whose upper bound is
4014 * Ui[A1 := S1, ..., An := Sn] and whose lower bound is Bi.
4015 *
4016 * + Otherwise, Si = Ti.
4017 *
4018 * Capture conversion on any type other than a parameterized type
4019 * (4.5) acts as an identity conversion (5.1.1). Capture
4020 * conversions never require a special action at run time and
4021 * therefore never throw an exception at run time.
4022 *
4023 * Capture conversion is not applied recursively.
4024 */
4025 /**
4026 * Capture conversion as specified by the JLS.
4027 */
4029 public List<Type> capture(List<Type> ts) {
4030 List<Type> buf = List.nil();
4031 for (Type t : ts) {
4032 buf = buf.prepend(capture(t));
4033 }
4034 return buf.reverse();
4035 }
4037 public Type capture(Type t) {
4038 if (!t.hasTag(CLASS)) {
4039 return t;
4040 }
4041 if (t.getEnclosingType() != Type.noType) {
4042 Type capturedEncl = capture(t.getEnclosingType());
4043 if (capturedEncl != t.getEnclosingType()) {
4044 Type type1 = memberType(capturedEncl, t.tsym);
4045 t = subst(type1, t.tsym.type.getTypeArguments(), t.getTypeArguments());
4046 }
4047 }
4048 t = t.unannotatedType();
4049 ClassType cls = (ClassType)t;
4050 if (cls.isRaw() || !cls.isParameterized())
4051 return cls;
4053 ClassType G = (ClassType)cls.asElement().asType();
4054 List<Type> A = G.getTypeArguments();
4055 List<Type> T = cls.getTypeArguments();
4056 List<Type> S = freshTypeVariables(T);
4058 List<Type> currentA = A;
4059 List<Type> currentT = T;
4060 List<Type> currentS = S;
4061 boolean captured = false;
4062 while (!currentA.isEmpty() &&
4063 !currentT.isEmpty() &&
4064 !currentS.isEmpty()) {
4065 if (currentS.head != currentT.head) {
4066 captured = true;
4067 WildcardType Ti = (WildcardType)currentT.head.unannotatedType();
4068 Type Ui = currentA.head.getUpperBound();
4069 CapturedType Si = (CapturedType)currentS.head.unannotatedType();
4070 if (Ui == null)
4071 Ui = syms.objectType;
4072 switch (Ti.kind) {
4073 case UNBOUND:
4074 Si.bound = subst(Ui, A, S);
4075 Si.lower = syms.botType;
4076 break;
4077 case EXTENDS:
4078 Si.bound = glb(Ti.getExtendsBound(), subst(Ui, A, S));
4079 Si.lower = syms.botType;
4080 break;
4081 case SUPER:
4082 Si.bound = subst(Ui, A, S);
4083 Si.lower = Ti.getSuperBound();
4084 break;
4085 }
4086 Type tmpBound = Si.bound.hasTag(UNDETVAR) ? ((UndetVar)Si.bound).qtype : Si.bound;
4087 Type tmpLower = Si.lower.hasTag(UNDETVAR) ? ((UndetVar)Si.lower).qtype : Si.lower;
4088 if (!Si.bound.hasTag(ERROR) &&
4089 !Si.lower.hasTag(ERROR) &&
4090 isSameType(tmpBound, tmpLower, false)) {
4091 currentS.head = Si.bound;
4092 }
4093 }
4094 currentA = currentA.tail;
4095 currentT = currentT.tail;
4096 currentS = currentS.tail;
4097 }
4098 if (!currentA.isEmpty() || !currentT.isEmpty() || !currentS.isEmpty())
4099 return erasure(t); // some "rare" type involved
4101 if (captured)
4102 return new ClassType(cls.getEnclosingType(), S, cls.tsym);
4103 else
4104 return t;
4105 }
4106 // where
4107 public List<Type> freshTypeVariables(List<Type> types) {
4108 ListBuffer<Type> result = new ListBuffer<>();
4109 for (Type t : types) {
4110 if (t.hasTag(WILDCARD)) {
4111 t = t.unannotatedType();
4112 Type bound = ((WildcardType)t).getExtendsBound();
4113 if (bound == null)
4114 bound = syms.objectType;
4115 result.append(new CapturedType(capturedName,
4116 syms.noSymbol,
4117 bound,
4118 syms.botType,
4119 (WildcardType)t));
4120 } else {
4121 result.append(t);
4122 }
4123 }
4124 return result.toList();
4125 }
4126 // </editor-fold>
4128 // <editor-fold defaultstate="collapsed" desc="Internal utility methods">
4129 private boolean sideCast(Type from, Type to, Warner warn) {
4130 // We are casting from type $from$ to type $to$, which are
4131 // non-final unrelated types. This method
4132 // tries to reject a cast by transferring type parameters
4133 // from $to$ to $from$ by common superinterfaces.
4134 boolean reverse = false;
4135 Type target = to;
4136 if ((to.tsym.flags() & INTERFACE) == 0) {
4137 Assert.check((from.tsym.flags() & INTERFACE) != 0);
4138 reverse = true;
4139 to = from;
4140 from = target;
4141 }
4142 List<Type> commonSupers = superClosure(to, erasure(from));
4143 boolean giveWarning = commonSupers.isEmpty();
4144 // The arguments to the supers could be unified here to
4145 // get a more accurate analysis
4146 while (commonSupers.nonEmpty()) {
4147 Type t1 = asSuper(from, commonSupers.head.tsym);
4148 Type t2 = commonSupers.head; // same as asSuper(to, commonSupers.head.tsym);
4149 if (disjointTypes(t1.getTypeArguments(), t2.getTypeArguments()))
4150 return false;
4151 giveWarning = giveWarning || (reverse ? giveWarning(t2, t1) : giveWarning(t1, t2));
4152 commonSupers = commonSupers.tail;
4153 }
4154 if (giveWarning && !isReifiable(reverse ? from : to))
4155 warn.warn(LintCategory.UNCHECKED);
4156 if (!allowCovariantReturns)
4157 // reject if there is a common method signature with
4158 // incompatible return types.
4159 chk.checkCompatibleAbstracts(warn.pos(), from, to);
4160 return true;
4161 }
4163 private boolean sideCastFinal(Type from, Type to, Warner warn) {
4164 // We are casting from type $from$ to type $to$, which are
4165 // unrelated types one of which is final and the other of
4166 // which is an interface. This method
4167 // tries to reject a cast by transferring type parameters
4168 // from the final class to the interface.
4169 boolean reverse = false;
4170 Type target = to;
4171 if ((to.tsym.flags() & INTERFACE) == 0) {
4172 Assert.check((from.tsym.flags() & INTERFACE) != 0);
4173 reverse = true;
4174 to = from;
4175 from = target;
4176 }
4177 Assert.check((from.tsym.flags() & FINAL) != 0);
4178 Type t1 = asSuper(from, to.tsym);
4179 if (t1 == null) return false;
4180 Type t2 = to;
4181 if (disjointTypes(t1.getTypeArguments(), t2.getTypeArguments()))
4182 return false;
4183 if (!allowCovariantReturns)
4184 // reject if there is a common method signature with
4185 // incompatible return types.
4186 chk.checkCompatibleAbstracts(warn.pos(), from, to);
4187 if (!isReifiable(target) &&
4188 (reverse ? giveWarning(t2, t1) : giveWarning(t1, t2)))
4189 warn.warn(LintCategory.UNCHECKED);
4190 return true;
4191 }
4193 private boolean giveWarning(Type from, Type to) {
4194 List<Type> bounds = to.isCompound() ?
4195 ((IntersectionClassType)to.unannotatedType()).getComponents() : List.of(to);
4196 for (Type b : bounds) {
4197 Type subFrom = asSub(from, b.tsym);
4198 if (b.isParameterized() &&
4199 (!(isUnbounded(b) ||
4200 isSubtype(from, b) ||
4201 ((subFrom != null) && containsType(b.allparams(), subFrom.allparams()))))) {
4202 return true;
4203 }
4204 }
4205 return false;
4206 }
4208 private List<Type> superClosure(Type t, Type s) {
4209 List<Type> cl = List.nil();
4210 for (List<Type> l = interfaces(t); l.nonEmpty(); l = l.tail) {
4211 if (isSubtype(s, erasure(l.head))) {
4212 cl = insert(cl, l.head);
4213 } else {
4214 cl = union(cl, superClosure(l.head, s));
4215 }
4216 }
4217 return cl;
4218 }
4220 private boolean containsTypeEquivalent(Type t, Type s) {
4221 return
4222 isSameType(t, s) || // shortcut
4223 containsType(t, s) && containsType(s, t);
4224 }
4226 // <editor-fold defaultstate="collapsed" desc="adapt">
4227 /**
4228 * Adapt a type by computing a substitution which maps a source
4229 * type to a target type.
4230 *
4231 * @param source the source type
4232 * @param target the target type
4233 * @param from the type variables of the computed substitution
4234 * @param to the types of the computed substitution.
4235 */
4236 public void adapt(Type source,
4237 Type target,
4238 ListBuffer<Type> from,
4239 ListBuffer<Type> to) throws AdaptFailure {
4240 new Adapter(from, to).adapt(source, target);
4241 }
4243 class Adapter extends SimpleVisitor<Void, Type> {
4245 ListBuffer<Type> from;
4246 ListBuffer<Type> to;
4247 Map<Symbol,Type> mapping;
4249 Adapter(ListBuffer<Type> from, ListBuffer<Type> to) {
4250 this.from = from;
4251 this.to = to;
4252 mapping = new HashMap<Symbol,Type>();
4253 }
4255 public void adapt(Type source, Type target) throws AdaptFailure {
4256 visit(source, target);
4257 List<Type> fromList = from.toList();
4258 List<Type> toList = to.toList();
4259 while (!fromList.isEmpty()) {
4260 Type val = mapping.get(fromList.head.tsym);
4261 if (toList.head != val)
4262 toList.head = val;
4263 fromList = fromList.tail;
4264 toList = toList.tail;
4265 }
4266 }
4268 @Override
4269 public Void visitClassType(ClassType source, Type target) throws AdaptFailure {
4270 if (target.hasTag(CLASS))
4271 adaptRecursive(source.allparams(), target.allparams());
4272 return null;
4273 }
4275 @Override
4276 public Void visitArrayType(ArrayType source, Type target) throws AdaptFailure {
4277 if (target.hasTag(ARRAY))
4278 adaptRecursive(elemtype(source), elemtype(target));
4279 return null;
4280 }
4282 @Override
4283 public Void visitWildcardType(WildcardType source, Type target) throws AdaptFailure {
4284 if (source.isExtendsBound())
4285 adaptRecursive(wildUpperBound(source), wildUpperBound(target));
4286 else if (source.isSuperBound())
4287 adaptRecursive(wildLowerBound(source), wildLowerBound(target));
4288 return null;
4289 }
4291 @Override
4292 public Void visitTypeVar(TypeVar source, Type target) throws AdaptFailure {
4293 // Check to see if there is
4294 // already a mapping for $source$, in which case
4295 // the old mapping will be merged with the new
4296 Type val = mapping.get(source.tsym);
4297 if (val != null) {
4298 if (val.isSuperBound() && target.isSuperBound()) {
4299 val = isSubtype(wildLowerBound(val), wildLowerBound(target))
4300 ? target : val;
4301 } else if (val.isExtendsBound() && target.isExtendsBound()) {
4302 val = isSubtype(wildUpperBound(val), wildUpperBound(target))
4303 ? val : target;
4304 } else if (!isSameType(val, target)) {
4305 throw new AdaptFailure();
4306 }
4307 } else {
4308 val = target;
4309 from.append(source);
4310 to.append(target);
4311 }
4312 mapping.put(source.tsym, val);
4313 return null;
4314 }
4316 @Override
4317 public Void visitType(Type source, Type target) {
4318 return null;
4319 }
4321 private Set<TypePair> cache = new HashSet<TypePair>();
4323 private void adaptRecursive(Type source, Type target) {
4324 TypePair pair = new TypePair(source, target);
4325 if (cache.add(pair)) {
4326 try {
4327 visit(source, target);
4328 } finally {
4329 cache.remove(pair);
4330 }
4331 }
4332 }
4334 private void adaptRecursive(List<Type> source, List<Type> target) {
4335 if (source.length() == target.length()) {
4336 while (source.nonEmpty()) {
4337 adaptRecursive(source.head, target.head);
4338 source = source.tail;
4339 target = target.tail;
4340 }
4341 }
4342 }
4343 }
4345 public static class AdaptFailure extends RuntimeException {
4346 static final long serialVersionUID = -7490231548272701566L;
4347 }
4349 private void adaptSelf(Type t,
4350 ListBuffer<Type> from,
4351 ListBuffer<Type> to) {
4352 try {
4353 //if (t.tsym.type != t)
4354 adapt(t.tsym.type, t, from, to);
4355 } catch (AdaptFailure ex) {
4356 // Adapt should never fail calculating a mapping from
4357 // t.tsym.type to t as there can be no merge problem.
4358 throw new AssertionError(ex);
4359 }
4360 }
4361 // </editor-fold>
4363 /**
4364 * Rewrite all type variables (universal quantifiers) in the given
4365 * type to wildcards (existential quantifiers). This is used to
4366 * determine if a cast is allowed. For example, if high is true
4367 * and {@code T <: Number}, then {@code List<T>} is rewritten to
4368 * {@code List<? extends Number>}. Since {@code List<Integer> <:
4369 * List<? extends Number>} a {@code List<T>} can be cast to {@code
4370 * List<Integer>} with a warning.
4371 * @param t a type
4372 * @param high if true return an upper bound; otherwise a lower
4373 * bound
4374 * @param rewriteTypeVars only rewrite captured wildcards if false;
4375 * otherwise rewrite all type variables
4376 * @return the type rewritten with wildcards (existential
4377 * quantifiers) only
4378 */
4379 private Type rewriteQuantifiers(Type t, boolean high, boolean rewriteTypeVars) {
4380 return new Rewriter(high, rewriteTypeVars).visit(t);
4381 }
4383 class Rewriter extends UnaryVisitor<Type> {
4385 boolean high;
4386 boolean rewriteTypeVars;
4388 Rewriter(boolean high, boolean rewriteTypeVars) {
4389 this.high = high;
4390 this.rewriteTypeVars = rewriteTypeVars;
4391 }
4393 @Override
4394 public Type visitClassType(ClassType t, Void s) {
4395 ListBuffer<Type> rewritten = new ListBuffer<Type>();
4396 boolean changed = false;
4397 for (Type arg : t.allparams()) {
4398 Type bound = visit(arg);
4399 if (arg != bound) {
4400 changed = true;
4401 }
4402 rewritten.append(bound);
4403 }
4404 if (changed)
4405 return subst(t.tsym.type,
4406 t.tsym.type.allparams(),
4407 rewritten.toList());
4408 else
4409 return t;
4410 }
4412 public Type visitType(Type t, Void s) {
4413 return t;
4414 }
4416 @Override
4417 public Type visitCapturedType(CapturedType t, Void s) {
4418 Type w_bound = t.wildcard.type;
4419 Type bound = w_bound.contains(t) ?
4420 erasure(w_bound) :
4421 visit(w_bound);
4422 return rewriteAsWildcardType(visit(bound), t.wildcard.bound, t.wildcard.kind);
4423 }
4425 @Override
4426 public Type visitTypeVar(TypeVar t, Void s) {
4427 if (rewriteTypeVars) {
4428 Type bound = t.bound.contains(t) ?
4429 erasure(t.bound) :
4430 visit(t.bound);
4431 return rewriteAsWildcardType(bound, t, EXTENDS);
4432 } else {
4433 return t;
4434 }
4435 }
4437 @Override
4438 public Type visitWildcardType(WildcardType t, Void s) {
4439 Type bound2 = visit(t.type);
4440 return t.type == bound2 ? t : rewriteAsWildcardType(bound2, t.bound, t.kind);
4441 }
4443 private Type rewriteAsWildcardType(Type bound, TypeVar formal, BoundKind bk) {
4444 switch (bk) {
4445 case EXTENDS: return high ?
4446 makeExtendsWildcard(B(bound), formal) :
4447 makeExtendsWildcard(syms.objectType, formal);
4448 case SUPER: return high ?
4449 makeSuperWildcard(syms.botType, formal) :
4450 makeSuperWildcard(B(bound), formal);
4451 case UNBOUND: return makeExtendsWildcard(syms.objectType, formal);
4452 default:
4453 Assert.error("Invalid bound kind " + bk);
4454 return null;
4455 }
4456 }
4458 Type B(Type t) {
4459 while (t.hasTag(WILDCARD)) {
4460 WildcardType w = (WildcardType)t.unannotatedType();
4461 t = high ?
4462 w.getExtendsBound() :
4463 w.getSuperBound();
4464 if (t == null) {
4465 t = high ? syms.objectType : syms.botType;
4466 }
4467 }
4468 return t;
4469 }
4470 }
4473 /**
4474 * Create a wildcard with the given upper (extends) bound; create
4475 * an unbounded wildcard if bound is Object.
4476 *
4477 * @param bound the upper bound
4478 * @param formal the formal type parameter that will be
4479 * substituted by the wildcard
4480 */
4481 private WildcardType makeExtendsWildcard(Type bound, TypeVar formal) {
4482 if (bound == syms.objectType) {
4483 return new WildcardType(syms.objectType,
4484 BoundKind.UNBOUND,
4485 syms.boundClass,
4486 formal);
4487 } else {
4488 return new WildcardType(bound,
4489 BoundKind.EXTENDS,
4490 syms.boundClass,
4491 formal);
4492 }
4493 }
4495 /**
4496 * Create a wildcard with the given lower (super) bound; create an
4497 * unbounded wildcard if bound is bottom (type of {@code null}).
4498 *
4499 * @param bound the lower bound
4500 * @param formal the formal type parameter that will be
4501 * substituted by the wildcard
4502 */
4503 private WildcardType makeSuperWildcard(Type bound, TypeVar formal) {
4504 if (bound.hasTag(BOT)) {
4505 return new WildcardType(syms.objectType,
4506 BoundKind.UNBOUND,
4507 syms.boundClass,
4508 formal);
4509 } else {
4510 return new WildcardType(bound,
4511 BoundKind.SUPER,
4512 syms.boundClass,
4513 formal);
4514 }
4515 }
4517 /**
4518 * A wrapper for a type that allows use in sets.
4519 */
4520 public static class UniqueType {
4521 public final Type type;
4522 final Types types;
4524 public UniqueType(Type type, Types types) {
4525 this.type = type;
4526 this.types = types;
4527 }
4529 public int hashCode() {
4530 return types.hashCode(type);
4531 }
4533 public boolean equals(Object obj) {
4534 return (obj instanceof UniqueType) &&
4535 types.isSameAnnotatedType(type, ((UniqueType)obj).type);
4536 }
4538 public String toString() {
4539 return type.toString();
4540 }
4542 }
4543 // </editor-fold>
4545 // <editor-fold defaultstate="collapsed" desc="Visitors">
4546 /**
4547 * A default visitor for types. All visitor methods except
4548 * visitType are implemented by delegating to visitType. Concrete
4549 * subclasses must provide an implementation of visitType and can
4550 * override other methods as needed.
4551 *
4552 * @param <R> the return type of the operation implemented by this
4553 * visitor; use Void if no return type is needed.
4554 * @param <S> the type of the second argument (the first being the
4555 * type itself) of the operation implemented by this visitor; use
4556 * Void if a second argument is not needed.
4557 */
4558 public static abstract class DefaultTypeVisitor<R,S> implements Type.Visitor<R,S> {
4559 final public R visit(Type t, S s) { return t.accept(this, s); }
4560 public R visitClassType(ClassType t, S s) { return visitType(t, s); }
4561 public R visitWildcardType(WildcardType t, S s) { return visitType(t, s); }
4562 public R visitArrayType(ArrayType t, S s) { return visitType(t, s); }
4563 public R visitMethodType(MethodType t, S s) { return visitType(t, s); }
4564 public R visitPackageType(PackageType t, S s) { return visitType(t, s); }
4565 public R visitTypeVar(TypeVar t, S s) { return visitType(t, s); }
4566 public R visitCapturedType(CapturedType t, S s) { return visitType(t, s); }
4567 public R visitForAll(ForAll t, S s) { return visitType(t, s); }
4568 public R visitUndetVar(UndetVar t, S s) { return visitType(t, s); }
4569 public R visitErrorType(ErrorType t, S s) { return visitType(t, s); }
4570 // Pretend annotations don't exist
4571 public R visitAnnotatedType(AnnotatedType t, S s) { return visit(t.unannotatedType(), s); }
4572 }
4574 /**
4575 * A default visitor for symbols. All visitor methods except
4576 * visitSymbol are implemented by delegating to visitSymbol. Concrete
4577 * subclasses must provide an implementation of visitSymbol and can
4578 * override other methods as needed.
4579 *
4580 * @param <R> the return type of the operation implemented by this
4581 * visitor; use Void if no return type is needed.
4582 * @param <S> the type of the second argument (the first being the
4583 * symbol itself) of the operation implemented by this visitor; use
4584 * Void if a second argument is not needed.
4585 */
4586 public static abstract class DefaultSymbolVisitor<R,S> implements Symbol.Visitor<R,S> {
4587 final public R visit(Symbol s, S arg) { return s.accept(this, arg); }
4588 public R visitClassSymbol(ClassSymbol s, S arg) { return visitSymbol(s, arg); }
4589 public R visitMethodSymbol(MethodSymbol s, S arg) { return visitSymbol(s, arg); }
4590 public R visitOperatorSymbol(OperatorSymbol s, S arg) { return visitSymbol(s, arg); }
4591 public R visitPackageSymbol(PackageSymbol s, S arg) { return visitSymbol(s, arg); }
4592 public R visitTypeSymbol(TypeSymbol s, S arg) { return visitSymbol(s, arg); }
4593 public R visitVarSymbol(VarSymbol s, S arg) { return visitSymbol(s, arg); }
4594 }
4596 /**
4597 * A <em>simple</em> visitor for types. This visitor is simple as
4598 * captured wildcards, for-all types (generic methods), and
4599 * undetermined type variables (part of inference) are hidden.
4600 * Captured wildcards are hidden by treating them as type
4601 * variables and the rest are hidden by visiting their qtypes.
4602 *
4603 * @param <R> the return type of the operation implemented by this
4604 * visitor; use Void if no return type is needed.
4605 * @param <S> the type of the second argument (the first being the
4606 * type itself) of the operation implemented by this visitor; use
4607 * Void if a second argument is not needed.
4608 */
4609 public static abstract class SimpleVisitor<R,S> extends DefaultTypeVisitor<R,S> {
4610 @Override
4611 public R visitCapturedType(CapturedType t, S s) {
4612 return visitTypeVar(t, s);
4613 }
4614 @Override
4615 public R visitForAll(ForAll t, S s) {
4616 return visit(t.qtype, s);
4617 }
4618 @Override
4619 public R visitUndetVar(UndetVar t, S s) {
4620 return visit(t.qtype, s);
4621 }
4622 }
4624 /**
4625 * A plain relation on types. That is a 2-ary function on the
4626 * form Type × Type → Boolean.
4627 * <!-- In plain text: Type x Type -> Boolean -->
4628 */
4629 public static abstract class TypeRelation extends SimpleVisitor<Boolean,Type> {}
4631 /**
4632 * A convenience visitor for implementing operations that only
4633 * require one argument (the type itself), that is, unary
4634 * operations.
4635 *
4636 * @param <R> the return type of the operation implemented by this
4637 * visitor; use Void if no return type is needed.
4638 */
4639 public static abstract class UnaryVisitor<R> extends SimpleVisitor<R,Void> {
4640 final public R visit(Type t) { return t.accept(this, null); }
4641 }
4643 /**
4644 * A visitor for implementing a mapping from types to types. The
4645 * default behavior of this class is to implement the identity
4646 * mapping (mapping a type to itself). This can be overridden in
4647 * subclasses.
4648 *
4649 * @param <S> the type of the second argument (the first being the
4650 * type itself) of this mapping; use Void if a second argument is
4651 * not needed.
4652 */
4653 public static class MapVisitor<S> extends DefaultTypeVisitor<Type,S> {
4654 final public Type visit(Type t) { return t.accept(this, null); }
4655 public Type visitType(Type t, S s) { return t; }
4656 }
4657 // </editor-fold>
4660 // <editor-fold defaultstate="collapsed" desc="Annotation support">
4662 public RetentionPolicy getRetention(Attribute.Compound a) {
4663 return getRetention(a.type.tsym);
4664 }
4666 public RetentionPolicy getRetention(Symbol sym) {
4667 RetentionPolicy vis = RetentionPolicy.CLASS; // the default
4668 Attribute.Compound c = sym.attribute(syms.retentionType.tsym);
4669 if (c != null) {
4670 Attribute value = c.member(names.value);
4671 if (value != null && value instanceof Attribute.Enum) {
4672 Name levelName = ((Attribute.Enum)value).value.name;
4673 if (levelName == names.SOURCE) vis = RetentionPolicy.SOURCE;
4674 else if (levelName == names.CLASS) vis = RetentionPolicy.CLASS;
4675 else if (levelName == names.RUNTIME) vis = RetentionPolicy.RUNTIME;
4676 else ;// /* fail soft */ throw new AssertionError(levelName);
4677 }
4678 }
4679 return vis;
4680 }
4681 // </editor-fold>
4683 // <editor-fold defaultstate="collapsed" desc="Signature Generation">
4685 public static abstract class SignatureGenerator {
4687 private final Types types;
4689 protected abstract void append(char ch);
4690 protected abstract void append(byte[] ba);
4691 protected abstract void append(Name name);
4692 protected void classReference(ClassSymbol c) { /* by default: no-op */ }
4694 protected SignatureGenerator(Types types) {
4695 this.types = types;
4696 }
4698 /**
4699 * Assemble signature of given type in string buffer.
4700 */
4701 public void assembleSig(Type type) {
4702 type = type.unannotatedType();
4703 switch (type.getTag()) {
4704 case BYTE:
4705 append('B');
4706 break;
4707 case SHORT:
4708 append('S');
4709 break;
4710 case CHAR:
4711 append('C');
4712 break;
4713 case INT:
4714 append('I');
4715 break;
4716 case LONG:
4717 append('J');
4718 break;
4719 case FLOAT:
4720 append('F');
4721 break;
4722 case DOUBLE:
4723 append('D');
4724 break;
4725 case BOOLEAN:
4726 append('Z');
4727 break;
4728 case VOID:
4729 append('V');
4730 break;
4731 case CLASS:
4732 append('L');
4733 assembleClassSig(type);
4734 append(';');
4735 break;
4736 case ARRAY:
4737 ArrayType at = (ArrayType) type;
4738 append('[');
4739 assembleSig(at.elemtype);
4740 break;
4741 case METHOD:
4742 MethodType mt = (MethodType) type;
4743 append('(');
4744 assembleSig(mt.argtypes);
4745 append(')');
4746 assembleSig(mt.restype);
4747 if (hasTypeVar(mt.thrown)) {
4748 for (List<Type> l = mt.thrown; l.nonEmpty(); l = l.tail) {
4749 append('^');
4750 assembleSig(l.head);
4751 }
4752 }
4753 break;
4754 case WILDCARD: {
4755 Type.WildcardType ta = (Type.WildcardType) type;
4756 switch (ta.kind) {
4757 case SUPER:
4758 append('-');
4759 assembleSig(ta.type);
4760 break;
4761 case EXTENDS:
4762 append('+');
4763 assembleSig(ta.type);
4764 break;
4765 case UNBOUND:
4766 append('*');
4767 break;
4768 default:
4769 throw new AssertionError(ta.kind);
4770 }
4771 break;
4772 }
4773 case TYPEVAR:
4774 append('T');
4775 append(type.tsym.name);
4776 append(';');
4777 break;
4778 case FORALL:
4779 Type.ForAll ft = (Type.ForAll) type;
4780 assembleParamsSig(ft.tvars);
4781 assembleSig(ft.qtype);
4782 break;
4783 default:
4784 throw new AssertionError("typeSig " + type.getTag());
4785 }
4786 }
4788 public boolean hasTypeVar(List<Type> l) {
4789 while (l.nonEmpty()) {
4790 if (l.head.hasTag(TypeTag.TYPEVAR)) {
4791 return true;
4792 }
4793 l = l.tail;
4794 }
4795 return false;
4796 }
4798 public void assembleClassSig(Type type) {
4799 type = type.unannotatedType();
4800 ClassType ct = (ClassType) type;
4801 ClassSymbol c = (ClassSymbol) ct.tsym;
4802 classReference(c);
4803 Type outer = ct.getEnclosingType();
4804 if (outer.allparams().nonEmpty()) {
4805 boolean rawOuter =
4806 c.owner.kind == Kinds.MTH || // either a local class
4807 c.name == types.names.empty; // or anonymous
4808 assembleClassSig(rawOuter
4809 ? types.erasure(outer)
4810 : outer);
4811 append(rawOuter ? '$' : '.');
4812 Assert.check(c.flatname.startsWith(c.owner.enclClass().flatname));
4813 append(rawOuter
4814 ? c.flatname.subName(c.owner.enclClass().flatname.getByteLength() + 1, c.flatname.getByteLength())
4815 : c.name);
4816 } else {
4817 append(externalize(c.flatname));
4818 }
4819 if (ct.getTypeArguments().nonEmpty()) {
4820 append('<');
4821 assembleSig(ct.getTypeArguments());
4822 append('>');
4823 }
4824 }
4826 public void assembleParamsSig(List<Type> typarams) {
4827 append('<');
4828 for (List<Type> ts = typarams; ts.nonEmpty(); ts = ts.tail) {
4829 Type.TypeVar tvar = (Type.TypeVar) ts.head;
4830 append(tvar.tsym.name);
4831 List<Type> bounds = types.getBounds(tvar);
4832 if ((bounds.head.tsym.flags() & INTERFACE) != 0) {
4833 append(':');
4834 }
4835 for (List<Type> l = bounds; l.nonEmpty(); l = l.tail) {
4836 append(':');
4837 assembleSig(l.head);
4838 }
4839 }
4840 append('>');
4841 }
4843 private void assembleSig(List<Type> types) {
4844 for (List<Type> ts = types; ts.nonEmpty(); ts = ts.tail) {
4845 assembleSig(ts.head);
4846 }
4847 }
4848 }
4849 // </editor-fold>
4850 }
