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src/share/classes/com/sun/tools/javac/code/Types.java@995bcdb9a41d
src/share/classes/com/sun/tools/javac/code/Types.java
Mon, 23 Aug 2010 16:59:30 +0100
- author
- mcimadamore
- date
- Mon, 23 Aug 2010 16:59:30 +0100
- changeset 640
- 995bcdb9a41d
- parent 637
- c655e0280bdc
- child 657
- 70ebdef189c9
- permissions
- -rw-r--r--
6932571: Compiling Generics causing Inconvertible types
Summary: Types.rewriteQuantifiers() does not work well with recursive type-variable bounds
Reviewed-by: jjg
1 /*
2 * Copyright (c) 2003, 2009, 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.*;
31 import com.sun.tools.javac.util.*;
32 import com.sun.tools.javac.util.List;
34 import com.sun.tools.javac.jvm.ClassReader;
35 import com.sun.tools.javac.comp.Check;
37 import static com.sun.tools.javac.code.Type.*;
38 import static com.sun.tools.javac.code.TypeTags.*;
39 import static com.sun.tools.javac.code.Symbol.*;
40 import static com.sun.tools.javac.code.Flags.*;
41 import static com.sun.tools.javac.code.BoundKind.*;
42 import static com.sun.tools.javac.util.ListBuffer.lb;
44 /**
45 * Utility class containing various operations on types.
46 *
47 * <p>Unless other names are more illustrative, the following naming
48 * conventions should be observed in this file:
49 *
50 * <dl>
51 * <dt>t</dt>
52 * <dd>If the first argument to an operation is a type, it should be named t.</dd>
53 * <dt>s</dt>
54 * <dd>Similarly, if the second argument to an operation is a type, it should be named s.</dd>
55 * <dt>ts</dt>
56 * <dd>If an operations takes a list of types, the first should be named ts.</dd>
57 * <dt>ss</dt>
58 * <dd>A second list of types should be named ss.</dd>
59 * </dl>
60 *
61 * <p><b>This is NOT part of any supported API.
62 * If you write code that depends on this, you do so at your own risk.
63 * This code and its internal interfaces are subject to change or
64 * deletion without notice.</b>
65 */
66 public class Types {
67 protected static final Context.Key<Types> typesKey =
68 new Context.Key<Types>();
70 final Symtab syms;
71 final JavacMessages messages;
72 final Names names;
73 final boolean allowBoxing;
74 final ClassReader reader;
75 final Source source;
76 final Check chk;
77 List<Warner> warnStack = List.nil();
78 final Name capturedName;
80 // <editor-fold defaultstate="collapsed" desc="Instantiating">
81 public static Types instance(Context context) {
82 Types instance = context.get(typesKey);
83 if (instance == null)
84 instance = new Types(context);
85 return instance;
86 }
88 protected Types(Context context) {
89 context.put(typesKey, this);
90 syms = Symtab.instance(context);
91 names = Names.instance(context);
92 allowBoxing = Source.instance(context).allowBoxing();
93 reader = ClassReader.instance(context);
94 source = Source.instance(context);
95 chk = Check.instance(context);
96 capturedName = names.fromString("<captured wildcard>");
97 messages = JavacMessages.instance(context);
98 }
99 // </editor-fold>
101 // <editor-fold defaultstate="collapsed" desc="upperBound">
102 /**
103 * The "rvalue conversion".<br>
104 * The upper bound of most types is the type
105 * itself. Wildcards, on the other hand have upper
106 * and lower bounds.
107 * @param t a type
108 * @return the upper bound of the given type
109 */
110 public Type upperBound(Type t) {
111 return upperBound.visit(t);
112 }
113 // where
114 private final MapVisitor<Void> upperBound = new MapVisitor<Void>() {
116 @Override
117 public Type visitWildcardType(WildcardType t, Void ignored) {
118 if (t.isSuperBound())
119 return t.bound == null ? syms.objectType : t.bound.bound;
120 else
121 return visit(t.type);
122 }
124 @Override
125 public Type visitCapturedType(CapturedType t, Void ignored) {
126 return visit(t.bound);
127 }
128 };
129 // </editor-fold>
131 // <editor-fold defaultstate="collapsed" desc="lowerBound">
132 /**
133 * The "lvalue conversion".<br>
134 * The lower bound of most types is the type
135 * itself. Wildcards, on the other hand have upper
136 * and lower bounds.
137 * @param t a type
138 * @return the lower bound of the given type
139 */
140 public Type lowerBound(Type t) {
141 return lowerBound.visit(t);
142 }
143 // where
144 private final MapVisitor<Void> lowerBound = new MapVisitor<Void>() {
146 @Override
147 public Type visitWildcardType(WildcardType t, Void ignored) {
148 return t.isExtendsBound() ? syms.botType : visit(t.type);
149 }
151 @Override
152 public Type visitCapturedType(CapturedType t, Void ignored) {
153 return visit(t.getLowerBound());
154 }
155 };
156 // </editor-fold>
158 // <editor-fold defaultstate="collapsed" desc="isUnbounded">
159 /**
160 * Checks that all the arguments to a class are unbounded
161 * wildcards or something else that doesn't make any restrictions
162 * on the arguments. If a class isUnbounded, a raw super- or
163 * subclass can be cast to it without a warning.
164 * @param t a type
165 * @return true iff the given type is unbounded or raw
166 */
167 public boolean isUnbounded(Type t) {
168 return isUnbounded.visit(t);
169 }
170 // where
171 private final UnaryVisitor<Boolean> isUnbounded = new UnaryVisitor<Boolean>() {
173 public Boolean visitType(Type t, Void ignored) {
174 return true;
175 }
177 @Override
178 public Boolean visitClassType(ClassType t, Void ignored) {
179 List<Type> parms = t.tsym.type.allparams();
180 List<Type> args = t.allparams();
181 while (parms.nonEmpty()) {
182 WildcardType unb = new WildcardType(syms.objectType,
183 BoundKind.UNBOUND,
184 syms.boundClass,
185 (TypeVar)parms.head);
186 if (!containsType(args.head, unb))
187 return false;
188 parms = parms.tail;
189 args = args.tail;
190 }
191 return true;
192 }
193 };
194 // </editor-fold>
196 // <editor-fold defaultstate="collapsed" desc="asSub">
197 /**
198 * Return the least specific subtype of t that starts with symbol
199 * sym. If none exists, return null. The least specific subtype
200 * is determined as follows:
201 *
202 * <p>If there is exactly one parameterized instance of sym that is a
203 * subtype of t, that parameterized instance is returned.<br>
204 * Otherwise, if the plain type or raw type `sym' is a subtype of
205 * type t, the type `sym' itself is returned. Otherwise, null is
206 * returned.
207 */
208 public Type asSub(Type t, Symbol sym) {
209 return asSub.visit(t, sym);
210 }
211 // where
212 private final SimpleVisitor<Type,Symbol> asSub = new SimpleVisitor<Type,Symbol>() {
214 public Type visitType(Type t, Symbol sym) {
215 return null;
216 }
218 @Override
219 public Type visitClassType(ClassType t, Symbol sym) {
220 if (t.tsym == sym)
221 return t;
222 Type base = asSuper(sym.type, t.tsym);
223 if (base == null)
224 return null;
225 ListBuffer<Type> from = new ListBuffer<Type>();
226 ListBuffer<Type> to = new ListBuffer<Type>();
227 try {
228 adapt(base, t, from, to);
229 } catch (AdaptFailure ex) {
230 return null;
231 }
232 Type res = subst(sym.type, from.toList(), to.toList());
233 if (!isSubtype(res, t))
234 return null;
235 ListBuffer<Type> openVars = new ListBuffer<Type>();
236 for (List<Type> l = sym.type.allparams();
237 l.nonEmpty(); l = l.tail)
238 if (res.contains(l.head) && !t.contains(l.head))
239 openVars.append(l.head);
240 if (openVars.nonEmpty()) {
241 if (t.isRaw()) {
242 // The subtype of a raw type is raw
243 res = erasure(res);
244 } else {
245 // Unbound type arguments default to ?
246 List<Type> opens = openVars.toList();
247 ListBuffer<Type> qs = new ListBuffer<Type>();
248 for (List<Type> iter = opens; iter.nonEmpty(); iter = iter.tail) {
249 qs.append(new WildcardType(syms.objectType, BoundKind.UNBOUND, syms.boundClass, (TypeVar) iter.head));
250 }
251 res = subst(res, opens, qs.toList());
252 }
253 }
254 return res;
255 }
257 @Override
258 public Type visitErrorType(ErrorType t, Symbol sym) {
259 return t;
260 }
261 };
262 // </editor-fold>
264 // <editor-fold defaultstate="collapsed" desc="isConvertible">
265 /**
266 * Is t a subtype of or convertiable via boxing/unboxing
267 * convertions to s?
268 */
269 public boolean isConvertible(Type t, Type s, Warner warn) {
270 boolean tPrimitive = t.isPrimitive();
271 boolean sPrimitive = s.isPrimitive();
272 if (tPrimitive == sPrimitive)
273 return isSubtypeUnchecked(t, s, warn);
274 if (!allowBoxing) return false;
275 return tPrimitive
276 ? isSubtype(boxedClass(t).type, s)
277 : isSubtype(unboxedType(t), s);
278 }
280 /**
281 * Is t a subtype of or convertiable via boxing/unboxing
282 * convertions to s?
283 */
284 public boolean isConvertible(Type t, Type s) {
285 return isConvertible(t, s, Warner.noWarnings);
286 }
287 // </editor-fold>
289 // <editor-fold defaultstate="collapsed" desc="isSubtype">
290 /**
291 * Is t an unchecked subtype of s?
292 */
293 public boolean isSubtypeUnchecked(Type t, Type s) {
294 return isSubtypeUnchecked(t, s, Warner.noWarnings);
295 }
296 /**
297 * Is t an unchecked subtype of s?
298 */
299 public boolean isSubtypeUnchecked(Type t, Type s, Warner warn) {
300 if (t.tag == ARRAY && s.tag == ARRAY) {
301 return (((ArrayType)t).elemtype.tag <= lastBaseTag)
302 ? isSameType(elemtype(t), elemtype(s))
303 : isSubtypeUnchecked(elemtype(t), elemtype(s), warn);
304 } else if (isSubtype(t, s)) {
305 return true;
306 }
307 else if (t.tag == TYPEVAR) {
308 return isSubtypeUnchecked(t.getUpperBound(), s, warn);
309 }
310 else if (s.tag == UNDETVAR) {
311 UndetVar uv = (UndetVar)s;
312 if (uv.inst != null)
313 return isSubtypeUnchecked(t, uv.inst, warn);
314 }
315 else if (!s.isRaw()) {
316 Type t2 = asSuper(t, s.tsym);
317 if (t2 != null && t2.isRaw()) {
318 if (isReifiable(s))
319 warn.silentUnchecked();
320 else
321 warn.warnUnchecked();
322 return true;
323 }
324 }
325 return false;
326 }
328 /**
329 * Is t a subtype of s?<br>
330 * (not defined for Method and ForAll types)
331 */
332 final public boolean isSubtype(Type t, Type s) {
333 return isSubtype(t, s, true);
334 }
335 final public boolean isSubtypeNoCapture(Type t, Type s) {
336 return isSubtype(t, s, false);
337 }
338 public boolean isSubtype(Type t, Type s, boolean capture) {
339 if (t == s)
340 return true;
342 if (s.tag >= firstPartialTag)
343 return isSuperType(s, t);
345 if (s.isCompound()) {
346 for (Type s2 : interfaces(s).prepend(supertype(s))) {
347 if (!isSubtype(t, s2, capture))
348 return false;
349 }
350 return true;
351 }
353 Type lower = lowerBound(s);
354 if (s != lower)
355 return isSubtype(capture ? capture(t) : t, lower, false);
357 return isSubtype.visit(capture ? capture(t) : t, s);
358 }
359 // where
360 private TypeRelation isSubtype = new TypeRelation()
361 {
362 public Boolean visitType(Type t, Type s) {
363 switch (t.tag) {
364 case BYTE: case CHAR:
365 return (t.tag == s.tag ||
366 t.tag + 2 <= s.tag && s.tag <= DOUBLE);
367 case SHORT: case INT: case LONG: case FLOAT: case DOUBLE:
368 return t.tag <= s.tag && s.tag <= DOUBLE;
369 case BOOLEAN: case VOID:
370 return t.tag == s.tag;
371 case TYPEVAR:
372 return isSubtypeNoCapture(t.getUpperBound(), s);
373 case BOT:
374 return
375 s.tag == BOT || s.tag == CLASS ||
376 s.tag == ARRAY || s.tag == TYPEVAR;
377 case NONE:
378 return false;
379 default:
380 throw new AssertionError("isSubtype " + t.tag);
381 }
382 }
384 private Set<TypePair> cache = new HashSet<TypePair>();
386 private boolean containsTypeRecursive(Type t, Type s) {
387 TypePair pair = new TypePair(t, s);
388 if (cache.add(pair)) {
389 try {
390 return containsType(t.getTypeArguments(),
391 s.getTypeArguments());
392 } finally {
393 cache.remove(pair);
394 }
395 } else {
396 return containsType(t.getTypeArguments(),
397 rewriteSupers(s).getTypeArguments());
398 }
399 }
401 private Type rewriteSupers(Type t) {
402 if (!t.isParameterized())
403 return t;
404 ListBuffer<Type> from = lb();
405 ListBuffer<Type> to = lb();
406 adaptSelf(t, from, to);
407 if (from.isEmpty())
408 return t;
409 ListBuffer<Type> rewrite = lb();
410 boolean changed = false;
411 for (Type orig : to.toList()) {
412 Type s = rewriteSupers(orig);
413 if (s.isSuperBound() && !s.isExtendsBound()) {
414 s = new WildcardType(syms.objectType,
415 BoundKind.UNBOUND,
416 syms.boundClass);
417 changed = true;
418 } else if (s != orig) {
419 s = new WildcardType(upperBound(s),
420 BoundKind.EXTENDS,
421 syms.boundClass);
422 changed = true;
423 }
424 rewrite.append(s);
425 }
426 if (changed)
427 return subst(t.tsym.type, from.toList(), rewrite.toList());
428 else
429 return t;
430 }
432 @Override
433 public Boolean visitClassType(ClassType t, Type s) {
434 Type sup = asSuper(t, s.tsym);
435 return sup != null
436 && sup.tsym == s.tsym
437 // You're not allowed to write
438 // Vector<Object> vec = new Vector<String>();
439 // But with wildcards you can write
440 // Vector<? extends Object> vec = new Vector<String>();
441 // which means that subtype checking must be done
442 // here instead of same-type checking (via containsType).
443 && (!s.isParameterized() || containsTypeRecursive(s, sup))
444 && isSubtypeNoCapture(sup.getEnclosingType(),
445 s.getEnclosingType());
446 }
448 @Override
449 public Boolean visitArrayType(ArrayType t, Type s) {
450 if (s.tag == ARRAY) {
451 if (t.elemtype.tag <= lastBaseTag)
452 return isSameType(t.elemtype, elemtype(s));
453 else
454 return isSubtypeNoCapture(t.elemtype, elemtype(s));
455 }
457 if (s.tag == CLASS) {
458 Name sname = s.tsym.getQualifiedName();
459 return sname == names.java_lang_Object
460 || sname == names.java_lang_Cloneable
461 || sname == names.java_io_Serializable;
462 }
464 return false;
465 }
467 @Override
468 public Boolean visitUndetVar(UndetVar t, Type s) {
469 //todo: test against origin needed? or replace with substitution?
470 if (t == s || t.qtype == s || s.tag == ERROR || s.tag == UNKNOWN)
471 return true;
473 if (t.inst != null)
474 return isSubtypeNoCapture(t.inst, s); // TODO: ", warn"?
476 t.hibounds = t.hibounds.prepend(s);
477 return true;
478 }
480 @Override
481 public Boolean visitErrorType(ErrorType t, Type s) {
482 return true;
483 }
484 };
486 /**
487 * Is t a subtype of every type in given list `ts'?<br>
488 * (not defined for Method and ForAll types)<br>
489 * Allows unchecked conversions.
490 */
491 public boolean isSubtypeUnchecked(Type t, List<Type> ts, Warner warn) {
492 for (List<Type> l = ts; l.nonEmpty(); l = l.tail)
493 if (!isSubtypeUnchecked(t, l.head, warn))
494 return false;
495 return true;
496 }
498 /**
499 * Are corresponding elements of ts subtypes of ss? If lists are
500 * of different length, return false.
501 */
502 public boolean isSubtypes(List<Type> ts, List<Type> ss) {
503 while (ts.tail != null && ss.tail != null
504 /*inlined: ts.nonEmpty() && ss.nonEmpty()*/ &&
505 isSubtype(ts.head, ss.head)) {
506 ts = ts.tail;
507 ss = ss.tail;
508 }
509 return ts.tail == null && ss.tail == null;
510 /*inlined: ts.isEmpty() && ss.isEmpty();*/
511 }
513 /**
514 * Are corresponding elements of ts subtypes of ss, allowing
515 * unchecked conversions? If lists are of different length,
516 * return false.
517 **/
518 public boolean isSubtypesUnchecked(List<Type> ts, List<Type> ss, Warner warn) {
519 while (ts.tail != null && ss.tail != null
520 /*inlined: ts.nonEmpty() && ss.nonEmpty()*/ &&
521 isSubtypeUnchecked(ts.head, ss.head, warn)) {
522 ts = ts.tail;
523 ss = ss.tail;
524 }
525 return ts.tail == null && ss.tail == null;
526 /*inlined: ts.isEmpty() && ss.isEmpty();*/
527 }
528 // </editor-fold>
530 // <editor-fold defaultstate="collapsed" desc="isSuperType">
531 /**
532 * Is t a supertype of s?
533 */
534 public boolean isSuperType(Type t, Type s) {
535 switch (t.tag) {
536 case ERROR:
537 return true;
538 case UNDETVAR: {
539 UndetVar undet = (UndetVar)t;
540 if (t == s ||
541 undet.qtype == s ||
542 s.tag == ERROR ||
543 s.tag == BOT) return true;
544 if (undet.inst != null)
545 return isSubtype(s, undet.inst);
546 undet.lobounds = undet.lobounds.prepend(s);
547 return true;
548 }
549 default:
550 return isSubtype(s, t);
551 }
552 }
553 // </editor-fold>
555 // <editor-fold defaultstate="collapsed" desc="isSameType">
556 /**
557 * Are corresponding elements of the lists the same type? If
558 * lists are of different length, return false.
559 */
560 public boolean isSameTypes(List<Type> ts, List<Type> ss) {
561 while (ts.tail != null && ss.tail != null
562 /*inlined: ts.nonEmpty() && ss.nonEmpty()*/ &&
563 isSameType(ts.head, ss.head)) {
564 ts = ts.tail;
565 ss = ss.tail;
566 }
567 return ts.tail == null && ss.tail == null;
568 /*inlined: ts.isEmpty() && ss.isEmpty();*/
569 }
571 /**
572 * Is t the same type as s?
573 */
574 public boolean isSameType(Type t, Type s) {
575 return isSameType.visit(t, s);
576 }
577 // where
578 private TypeRelation isSameType = new TypeRelation() {
580 public Boolean visitType(Type t, Type s) {
581 if (t == s)
582 return true;
584 if (s.tag >= firstPartialTag)
585 return visit(s, t);
587 switch (t.tag) {
588 case BYTE: case CHAR: case SHORT: case INT: case LONG: case FLOAT:
589 case DOUBLE: case BOOLEAN: case VOID: case BOT: case NONE:
590 return t.tag == s.tag;
591 case TYPEVAR: {
592 if (s.tag == TYPEVAR) {
593 //type-substitution does not preserve type-var types
594 //check that type var symbols and bounds are indeed the same
595 return t.tsym == s.tsym &&
596 visit(t.getUpperBound(), s.getUpperBound());
597 }
598 else {
599 //special case for s == ? super X, where upper(s) = u
600 //check that u == t, where u has been set by Type.withTypeVar
601 return s.isSuperBound() &&
602 !s.isExtendsBound() &&
603 visit(t, upperBound(s));
604 }
605 }
606 default:
607 throw new AssertionError("isSameType " + t.tag);
608 }
609 }
611 @Override
612 public Boolean visitWildcardType(WildcardType t, Type s) {
613 if (s.tag >= firstPartialTag)
614 return visit(s, t);
615 else
616 return false;
617 }
619 @Override
620 public Boolean visitClassType(ClassType t, Type s) {
621 if (t == s)
622 return true;
624 if (s.tag >= firstPartialTag)
625 return visit(s, t);
627 if (s.isSuperBound() && !s.isExtendsBound())
628 return visit(t, upperBound(s)) && visit(t, lowerBound(s));
630 if (t.isCompound() && s.isCompound()) {
631 if (!visit(supertype(t), supertype(s)))
632 return false;
634 HashSet<SingletonType> set = new HashSet<SingletonType>();
635 for (Type x : interfaces(t))
636 set.add(new SingletonType(x));
637 for (Type x : interfaces(s)) {
638 if (!set.remove(new SingletonType(x)))
639 return false;
640 }
641 return (set.size() == 0);
642 }
643 return t.tsym == s.tsym
644 && visit(t.getEnclosingType(), s.getEnclosingType())
645 && containsTypeEquivalent(t.getTypeArguments(), s.getTypeArguments());
646 }
648 @Override
649 public Boolean visitArrayType(ArrayType t, Type s) {
650 if (t == s)
651 return true;
653 if (s.tag >= firstPartialTag)
654 return visit(s, t);
656 return s.tag == ARRAY
657 && containsTypeEquivalent(t.elemtype, elemtype(s));
658 }
660 @Override
661 public Boolean visitMethodType(MethodType t, Type s) {
662 // isSameType for methods does not take thrown
663 // exceptions into account!
664 return hasSameArgs(t, s) && visit(t.getReturnType(), s.getReturnType());
665 }
667 @Override
668 public Boolean visitPackageType(PackageType t, Type s) {
669 return t == s;
670 }
672 @Override
673 public Boolean visitForAll(ForAll t, Type s) {
674 if (s.tag != FORALL)
675 return false;
677 ForAll forAll = (ForAll)s;
678 return hasSameBounds(t, forAll)
679 && visit(t.qtype, subst(forAll.qtype, forAll.tvars, t.tvars));
680 }
682 @Override
683 public Boolean visitUndetVar(UndetVar t, Type s) {
684 if (s.tag == WILDCARD)
685 // FIXME, this might be leftovers from before capture conversion
686 return false;
688 if (t == s || t.qtype == s || s.tag == ERROR || s.tag == UNKNOWN)
689 return true;
691 if (t.inst != null)
692 return visit(t.inst, s);
694 t.inst = fromUnknownFun.apply(s);
695 for (List<Type> l = t.lobounds; l.nonEmpty(); l = l.tail) {
696 if (!isSubtype(l.head, t.inst))
697 return false;
698 }
699 for (List<Type> l = t.hibounds; l.nonEmpty(); l = l.tail) {
700 if (!isSubtype(t.inst, l.head))
701 return false;
702 }
703 return true;
704 }
706 @Override
707 public Boolean visitErrorType(ErrorType t, Type s) {
708 return true;
709 }
710 };
711 // </editor-fold>
713 // <editor-fold defaultstate="collapsed" desc="fromUnknownFun">
714 /**
715 * A mapping that turns all unknown types in this type to fresh
716 * unknown variables.
717 */
718 public Mapping fromUnknownFun = new Mapping("fromUnknownFun") {
719 public Type apply(Type t) {
720 if (t.tag == UNKNOWN) return new UndetVar(t);
721 else return t.map(this);
722 }
723 };
724 // </editor-fold>
726 // <editor-fold defaultstate="collapsed" desc="Contains Type">
727 public boolean containedBy(Type t, Type s) {
728 switch (t.tag) {
729 case UNDETVAR:
730 if (s.tag == WILDCARD) {
731 UndetVar undetvar = (UndetVar)t;
732 WildcardType wt = (WildcardType)s;
733 switch(wt.kind) {
734 case UNBOUND: //similar to ? extends Object
735 case EXTENDS: {
736 Type bound = upperBound(s);
737 // We should check the new upper bound against any of the
738 // undetvar's lower bounds.
739 for (Type t2 : undetvar.lobounds) {
740 if (!isSubtype(t2, bound))
741 return false;
742 }
743 undetvar.hibounds = undetvar.hibounds.prepend(bound);
744 break;
745 }
746 case SUPER: {
747 Type bound = lowerBound(s);
748 // We should check the new lower bound against any of the
749 // undetvar's lower bounds.
750 for (Type t2 : undetvar.hibounds) {
751 if (!isSubtype(bound, t2))
752 return false;
753 }
754 undetvar.lobounds = undetvar.lobounds.prepend(bound);
755 break;
756 }
757 }
758 return true;
759 } else {
760 return isSameType(t, s);
761 }
762 case ERROR:
763 return true;
764 default:
765 return containsType(s, t);
766 }
767 }
769 boolean containsType(List<Type> ts, List<Type> ss) {
770 while (ts.nonEmpty() && ss.nonEmpty()
771 && containsType(ts.head, ss.head)) {
772 ts = ts.tail;
773 ss = ss.tail;
774 }
775 return ts.isEmpty() && ss.isEmpty();
776 }
778 /**
779 * Check if t contains s.
780 *
781 * <p>T contains S if:
782 *
783 * <p>{@code L(T) <: L(S) && U(S) <: U(T)}
784 *
785 * <p>This relation is only used by ClassType.isSubtype(), that
786 * is,
787 *
788 * <p>{@code C<S> <: C<T> if T contains S.}
789 *
790 * <p>Because of F-bounds, this relation can lead to infinite
791 * recursion. Thus we must somehow break that recursion. Notice
792 * that containsType() is only called from ClassType.isSubtype().
793 * Since the arguments have already been checked against their
794 * bounds, we know:
795 *
796 * <p>{@code U(S) <: U(T) if T is "super" bound (U(T) *is* the bound)}
797 *
798 * <p>{@code L(T) <: L(S) if T is "extends" bound (L(T) is bottom)}
799 *
800 * @param t a type
801 * @param s a type
802 */
803 public boolean containsType(Type t, Type s) {
804 return containsType.visit(t, s);
805 }
806 // where
807 private TypeRelation containsType = new TypeRelation() {
809 private Type U(Type t) {
810 while (t.tag == WILDCARD) {
811 WildcardType w = (WildcardType)t;
812 if (w.isSuperBound())
813 return w.bound == null ? syms.objectType : w.bound.bound;
814 else
815 t = w.type;
816 }
817 return t;
818 }
820 private Type L(Type t) {
821 while (t.tag == WILDCARD) {
822 WildcardType w = (WildcardType)t;
823 if (w.isExtendsBound())
824 return syms.botType;
825 else
826 t = w.type;
827 }
828 return t;
829 }
831 public Boolean visitType(Type t, Type s) {
832 if (s.tag >= firstPartialTag)
833 return containedBy(s, t);
834 else
835 return isSameType(t, s);
836 }
838 void debugContainsType(WildcardType t, Type s) {
839 System.err.println();
840 System.err.format(" does %s contain %s?%n", t, s);
841 System.err.format(" %s U(%s) <: U(%s) %s = %s%n",
842 upperBound(s), s, t, U(t),
843 t.isSuperBound()
844 || isSubtypeNoCapture(upperBound(s), U(t)));
845 System.err.format(" %s L(%s) <: L(%s) %s = %s%n",
846 L(t), t, s, lowerBound(s),
847 t.isExtendsBound()
848 || isSubtypeNoCapture(L(t), lowerBound(s)));
849 System.err.println();
850 }
852 @Override
853 public Boolean visitWildcardType(WildcardType t, Type s) {
854 if (s.tag >= firstPartialTag)
855 return containedBy(s, t);
856 else {
857 // debugContainsType(t, s);
858 return isSameWildcard(t, s)
859 || isCaptureOf(s, t)
860 || ((t.isExtendsBound() || isSubtypeNoCapture(L(t), lowerBound(s))) &&
861 (t.isSuperBound() || isSubtypeNoCapture(upperBound(s), U(t))));
862 }
863 }
865 @Override
866 public Boolean visitUndetVar(UndetVar t, Type s) {
867 if (s.tag != WILDCARD)
868 return isSameType(t, s);
869 else
870 return false;
871 }
873 @Override
874 public Boolean visitErrorType(ErrorType t, Type s) {
875 return true;
876 }
877 };
879 public boolean isCaptureOf(Type s, WildcardType t) {
880 if (s.tag != TYPEVAR || !((TypeVar)s).isCaptured())
881 return false;
882 return isSameWildcard(t, ((CapturedType)s).wildcard);
883 }
885 public boolean isSameWildcard(WildcardType t, Type s) {
886 if (s.tag != WILDCARD)
887 return false;
888 WildcardType w = (WildcardType)s;
889 return w.kind == t.kind && w.type == t.type;
890 }
892 public boolean containsTypeEquivalent(List<Type> ts, List<Type> ss) {
893 while (ts.nonEmpty() && ss.nonEmpty()
894 && containsTypeEquivalent(ts.head, ss.head)) {
895 ts = ts.tail;
896 ss = ss.tail;
897 }
898 return ts.isEmpty() && ss.isEmpty();
899 }
900 // </editor-fold>
902 // <editor-fold defaultstate="collapsed" desc="isCastable">
903 public boolean isCastable(Type t, Type s) {
904 return isCastable(t, s, Warner.noWarnings);
905 }
907 /**
908 * Is t is castable to s?<br>
909 * s is assumed to be an erased type.<br>
910 * (not defined for Method and ForAll types).
911 */
912 public boolean isCastable(Type t, Type s, Warner warn) {
913 if (t == s)
914 return true;
916 if (t.isPrimitive() != s.isPrimitive())
917 return allowBoxing && isConvertible(t, s, warn);
919 if (warn != warnStack.head) {
920 try {
921 warnStack = warnStack.prepend(warn);
922 return isCastable.visit(t,s);
923 } finally {
924 warnStack = warnStack.tail;
925 }
926 } else {
927 return isCastable.visit(t,s);
928 }
929 }
930 // where
931 private TypeRelation isCastable = new TypeRelation() {
933 public Boolean visitType(Type t, Type s) {
934 if (s.tag == ERROR)
935 return true;
937 switch (t.tag) {
938 case BYTE: case CHAR: case SHORT: case INT: case LONG: case FLOAT:
939 case DOUBLE:
940 return s.tag <= DOUBLE;
941 case BOOLEAN:
942 return s.tag == BOOLEAN;
943 case VOID:
944 return false;
945 case BOT:
946 return isSubtype(t, s);
947 default:
948 throw new AssertionError();
949 }
950 }
952 @Override
953 public Boolean visitWildcardType(WildcardType t, Type s) {
954 return isCastable(upperBound(t), s, warnStack.head);
955 }
957 @Override
958 public Boolean visitClassType(ClassType t, Type s) {
959 if (s.tag == ERROR || s.tag == BOT)
960 return true;
962 if (s.tag == TYPEVAR) {
963 if (isCastable(t, s.getUpperBound(), Warner.noWarnings)) {
964 warnStack.head.warnUnchecked();
965 return true;
966 } else {
967 return false;
968 }
969 }
971 if (t.isCompound()) {
972 Warner oldWarner = warnStack.head;
973 warnStack.head = Warner.noWarnings;
974 if (!visit(supertype(t), s))
975 return false;
976 for (Type intf : interfaces(t)) {
977 if (!visit(intf, s))
978 return false;
979 }
980 if (warnStack.head.unchecked == true)
981 oldWarner.warnUnchecked();
982 return true;
983 }
985 if (s.isCompound()) {
986 // call recursively to reuse the above code
987 return visitClassType((ClassType)s, t);
988 }
990 if (s.tag == CLASS || s.tag == ARRAY) {
991 boolean upcast;
992 if ((upcast = isSubtype(erasure(t), erasure(s)))
993 || isSubtype(erasure(s), erasure(t))) {
994 if (!upcast && s.tag == ARRAY) {
995 if (!isReifiable(s))
996 warnStack.head.warnUnchecked();
997 return true;
998 } else if (s.isRaw()) {
999 return true;
1000 } else if (t.isRaw()) {
1001 if (!isUnbounded(s))
1002 warnStack.head.warnUnchecked();
1003 return true;
1004 }
1005 // Assume |a| <: |b|
1006 final Type a = upcast ? t : s;
1007 final Type b = upcast ? s : t;
1008 final boolean HIGH = true;
1009 final boolean LOW = false;
1010 final boolean DONT_REWRITE_TYPEVARS = false;
1011 Type aHigh = rewriteQuantifiers(a, HIGH, DONT_REWRITE_TYPEVARS);
1012 Type aLow = rewriteQuantifiers(a, LOW, DONT_REWRITE_TYPEVARS);
1013 Type bHigh = rewriteQuantifiers(b, HIGH, DONT_REWRITE_TYPEVARS);
1014 Type bLow = rewriteQuantifiers(b, LOW, DONT_REWRITE_TYPEVARS);
1015 Type lowSub = asSub(bLow, aLow.tsym);
1016 Type highSub = (lowSub == null) ? null : asSub(bHigh, aHigh.tsym);
1017 if (highSub == null) {
1018 final boolean REWRITE_TYPEVARS = true;
1019 aHigh = rewriteQuantifiers(a, HIGH, REWRITE_TYPEVARS);
1020 aLow = rewriteQuantifiers(a, LOW, REWRITE_TYPEVARS);
1021 bHigh = rewriteQuantifiers(b, HIGH, REWRITE_TYPEVARS);
1022 bLow = rewriteQuantifiers(b, LOW, REWRITE_TYPEVARS);
1023 lowSub = asSub(bLow, aLow.tsym);
1024 highSub = (lowSub == null) ? null : asSub(bHigh, aHigh.tsym);
1025 }
1026 if (highSub != null) {
1027 assert a.tsym == highSub.tsym && a.tsym == lowSub.tsym
1028 : a.tsym + " != " + highSub.tsym + " != " + lowSub.tsym;
1029 if (!disjointTypes(aHigh.allparams(), highSub.allparams())
1030 && !disjointTypes(aHigh.allparams(), lowSub.allparams())
1031 && !disjointTypes(aLow.allparams(), highSub.allparams())
1032 && !disjointTypes(aLow.allparams(), lowSub.allparams())) {
1033 if (s.isInterface() &&
1034 !t.isInterface() &&
1035 t.isFinal() &&
1036 !isSubtype(t, s)) {
1037 return false;
1038 } else if (upcast ? giveWarning(a, b) :
1039 giveWarning(b, a))
1040 warnStack.head.warnUnchecked();
1041 return true;
1042 }
1043 }
1044 if (isReifiable(s))
1045 return isSubtypeUnchecked(a, b);
1046 else
1047 return isSubtypeUnchecked(a, b, warnStack.head);
1048 }
1050 // Sidecast
1051 if (s.tag == CLASS) {
1052 if ((s.tsym.flags() & INTERFACE) != 0) {
1053 return ((t.tsym.flags() & FINAL) == 0)
1054 ? sideCast(t, s, warnStack.head)
1055 : sideCastFinal(t, s, warnStack.head);
1056 } else if ((t.tsym.flags() & INTERFACE) != 0) {
1057 return ((s.tsym.flags() & FINAL) == 0)
1058 ? sideCast(t, s, warnStack.head)
1059 : sideCastFinal(t, s, warnStack.head);
1060 } else {
1061 // unrelated class types
1062 return false;
1063 }
1064 }
1065 }
1066 return false;
1067 }
1069 @Override
1070 public Boolean visitArrayType(ArrayType t, Type s) {
1071 switch (s.tag) {
1072 case ERROR:
1073 case BOT:
1074 return true;
1075 case TYPEVAR:
1076 if (isCastable(s, t, Warner.noWarnings)) {
1077 warnStack.head.warnUnchecked();
1078 return true;
1079 } else {
1080 return false;
1081 }
1082 case CLASS:
1083 return isSubtype(t, s);
1084 case ARRAY:
1085 if (elemtype(t).tag <= lastBaseTag) {
1086 return elemtype(t).tag == elemtype(s).tag;
1087 } else {
1088 return visit(elemtype(t), elemtype(s));
1089 }
1090 default:
1091 return false;
1092 }
1093 }
1095 @Override
1096 public Boolean visitTypeVar(TypeVar t, Type s) {
1097 switch (s.tag) {
1098 case ERROR:
1099 case BOT:
1100 return true;
1101 case TYPEVAR:
1102 if (isSubtype(t, s)) {
1103 return true;
1104 } else if (isCastable(t.bound, s, Warner.noWarnings)) {
1105 warnStack.head.warnUnchecked();
1106 return true;
1107 } else {
1108 return false;
1109 }
1110 default:
1111 return isCastable(t.bound, s, warnStack.head);
1112 }
1113 }
1115 @Override
1116 public Boolean visitErrorType(ErrorType t, Type s) {
1117 return true;
1118 }
1119 };
1120 // </editor-fold>
1122 // <editor-fold defaultstate="collapsed" desc="disjointTypes">
1123 public boolean disjointTypes(List<Type> ts, List<Type> ss) {
1124 while (ts.tail != null && ss.tail != null) {
1125 if (disjointType(ts.head, ss.head)) return true;
1126 ts = ts.tail;
1127 ss = ss.tail;
1128 }
1129 return false;
1130 }
1132 /**
1133 * Two types or wildcards are considered disjoint if it can be
1134 * proven that no type can be contained in both. It is
1135 * conservative in that it is allowed to say that two types are
1136 * not disjoint, even though they actually are.
1137 *
1138 * The type C<X> is castable to C<Y> exactly if X and Y are not
1139 * disjoint.
1140 */
1141 public boolean disjointType(Type t, Type s) {
1142 return disjointType.visit(t, s);
1143 }
1144 // where
1145 private TypeRelation disjointType = new TypeRelation() {
1147 private Set<TypePair> cache = new HashSet<TypePair>();
1149 public Boolean visitType(Type t, Type s) {
1150 if (s.tag == WILDCARD)
1151 return visit(s, t);
1152 else
1153 return notSoftSubtypeRecursive(t, s) || notSoftSubtypeRecursive(s, t);
1154 }
1156 private boolean isCastableRecursive(Type t, Type s) {
1157 TypePair pair = new TypePair(t, s);
1158 if (cache.add(pair)) {
1159 try {
1160 return Types.this.isCastable(t, s);
1161 } finally {
1162 cache.remove(pair);
1163 }
1164 } else {
1165 return true;
1166 }
1167 }
1169 private boolean notSoftSubtypeRecursive(Type t, Type s) {
1170 TypePair pair = new TypePair(t, s);
1171 if (cache.add(pair)) {
1172 try {
1173 return Types.this.notSoftSubtype(t, s);
1174 } finally {
1175 cache.remove(pair);
1176 }
1177 } else {
1178 return false;
1179 }
1180 }
1182 @Override
1183 public Boolean visitWildcardType(WildcardType t, Type s) {
1184 if (t.isUnbound())
1185 return false;
1187 if (s.tag != WILDCARD) {
1188 if (t.isExtendsBound())
1189 return notSoftSubtypeRecursive(s, t.type);
1190 else // isSuperBound()
1191 return notSoftSubtypeRecursive(t.type, s);
1192 }
1194 if (s.isUnbound())
1195 return false;
1197 if (t.isExtendsBound()) {
1198 if (s.isExtendsBound())
1199 return !isCastableRecursive(t.type, upperBound(s));
1200 else if (s.isSuperBound())
1201 return notSoftSubtypeRecursive(lowerBound(s), t.type);
1202 } else if (t.isSuperBound()) {
1203 if (s.isExtendsBound())
1204 return notSoftSubtypeRecursive(t.type, upperBound(s));
1205 }
1206 return false;
1207 }
1208 };
1209 // </editor-fold>
1211 // <editor-fold defaultstate="collapsed" desc="lowerBoundArgtypes">
1212 /**
1213 * Returns the lower bounds of the formals of a method.
1214 */
1215 public List<Type> lowerBoundArgtypes(Type t) {
1216 return map(t.getParameterTypes(), lowerBoundMapping);
1217 }
1218 private final Mapping lowerBoundMapping = new Mapping("lowerBound") {
1219 public Type apply(Type t) {
1220 return lowerBound(t);
1221 }
1222 };
1223 // </editor-fold>
1225 // <editor-fold defaultstate="collapsed" desc="notSoftSubtype">
1226 /**
1227 * This relation answers the question: is impossible that
1228 * something of type `t' can be a subtype of `s'? This is
1229 * different from the question "is `t' not a subtype of `s'?"
1230 * when type variables are involved: Integer is not a subtype of T
1231 * where <T extends Number> but it is not true that Integer cannot
1232 * possibly be a subtype of T.
1233 */
1234 public boolean notSoftSubtype(Type t, Type s) {
1235 if (t == s) return false;
1236 if (t.tag == TYPEVAR) {
1237 TypeVar tv = (TypeVar) t;
1238 return !isCastable(tv.bound,
1239 relaxBound(s),
1240 Warner.noWarnings);
1241 }
1242 if (s.tag != WILDCARD)
1243 s = upperBound(s);
1245 return !isSubtype(t, relaxBound(s));
1246 }
1248 private Type relaxBound(Type t) {
1249 if (t.tag == TYPEVAR) {
1250 while (t.tag == TYPEVAR)
1251 t = t.getUpperBound();
1252 t = rewriteQuantifiers(t, true, true);
1253 }
1254 return t;
1255 }
1256 // </editor-fold>
1258 // <editor-fold defaultstate="collapsed" desc="isReifiable">
1259 public boolean isReifiable(Type t) {
1260 return isReifiable.visit(t);
1261 }
1262 // where
1263 private UnaryVisitor<Boolean> isReifiable = new UnaryVisitor<Boolean>() {
1265 public Boolean visitType(Type t, Void ignored) {
1266 return true;
1267 }
1269 @Override
1270 public Boolean visitClassType(ClassType t, Void ignored) {
1271 if (t.isCompound())
1272 return false;
1273 else {
1274 if (!t.isParameterized())
1275 return true;
1277 for (Type param : t.allparams()) {
1278 if (!param.isUnbound())
1279 return false;
1280 }
1281 return true;
1282 }
1283 }
1285 @Override
1286 public Boolean visitArrayType(ArrayType t, Void ignored) {
1287 return visit(t.elemtype);
1288 }
1290 @Override
1291 public Boolean visitTypeVar(TypeVar t, Void ignored) {
1292 return false;
1293 }
1294 };
1295 // </editor-fold>
1297 // <editor-fold defaultstate="collapsed" desc="Array Utils">
1298 public boolean isArray(Type t) {
1299 while (t.tag == WILDCARD)
1300 t = upperBound(t);
1301 return t.tag == ARRAY;
1302 }
1304 /**
1305 * The element type of an array.
1306 */
1307 public Type elemtype(Type t) {
1308 switch (t.tag) {
1309 case WILDCARD:
1310 return elemtype(upperBound(t));
1311 case ARRAY:
1312 return ((ArrayType)t).elemtype;
1313 case FORALL:
1314 return elemtype(((ForAll)t).qtype);
1315 case ERROR:
1316 return t;
1317 default:
1318 return null;
1319 }
1320 }
1322 /**
1323 * Mapping to take element type of an arraytype
1324 */
1325 private Mapping elemTypeFun = new Mapping ("elemTypeFun") {
1326 public Type apply(Type t) { return elemtype(t); }
1327 };
1329 /**
1330 * The number of dimensions of an array type.
1331 */
1332 public int dimensions(Type t) {
1333 int result = 0;
1334 while (t.tag == ARRAY) {
1335 result++;
1336 t = elemtype(t);
1337 }
1338 return result;
1339 }
1340 // </editor-fold>
1342 // <editor-fold defaultstate="collapsed" desc="asSuper">
1343 /**
1344 * Return the (most specific) base type of t that starts with the
1345 * given symbol. If none exists, return null.
1346 *
1347 * @param t a type
1348 * @param sym a symbol
1349 */
1350 public Type asSuper(Type t, Symbol sym) {
1351 return asSuper.visit(t, sym);
1352 }
1353 // where
1354 private SimpleVisitor<Type,Symbol> asSuper = new SimpleVisitor<Type,Symbol>() {
1356 public Type visitType(Type t, Symbol sym) {
1357 return null;
1358 }
1360 @Override
1361 public Type visitClassType(ClassType t, Symbol sym) {
1362 if (t.tsym == sym)
1363 return t;
1365 Type st = supertype(t);
1366 if (st.tag == CLASS || st.tag == TYPEVAR || st.tag == ERROR) {
1367 Type x = asSuper(st, sym);
1368 if (x != null)
1369 return x;
1370 }
1371 if ((sym.flags() & INTERFACE) != 0) {
1372 for (List<Type> l = interfaces(t); l.nonEmpty(); l = l.tail) {
1373 Type x = asSuper(l.head, sym);
1374 if (x != null)
1375 return x;
1376 }
1377 }
1378 return null;
1379 }
1381 @Override
1382 public Type visitArrayType(ArrayType t, Symbol sym) {
1383 return isSubtype(t, sym.type) ? sym.type : null;
1384 }
1386 @Override
1387 public Type visitTypeVar(TypeVar t, Symbol sym) {
1388 if (t.tsym == sym)
1389 return t;
1390 else
1391 return asSuper(t.bound, sym);
1392 }
1394 @Override
1395 public Type visitErrorType(ErrorType t, Symbol sym) {
1396 return t;
1397 }
1398 };
1400 /**
1401 * Return the base type of t or any of its outer types that starts
1402 * with the given symbol. If none exists, return null.
1403 *
1404 * @param t a type
1405 * @param sym a symbol
1406 */
1407 public Type asOuterSuper(Type t, Symbol sym) {
1408 switch (t.tag) {
1409 case CLASS:
1410 do {
1411 Type s = asSuper(t, sym);
1412 if (s != null) return s;
1413 t = t.getEnclosingType();
1414 } while (t.tag == CLASS);
1415 return null;
1416 case ARRAY:
1417 return isSubtype(t, sym.type) ? sym.type : null;
1418 case TYPEVAR:
1419 return asSuper(t, sym);
1420 case ERROR:
1421 return t;
1422 default:
1423 return null;
1424 }
1425 }
1427 /**
1428 * Return the base type of t or any of its enclosing types that
1429 * starts with the given symbol. If none exists, return null.
1430 *
1431 * @param t a type
1432 * @param sym a symbol
1433 */
1434 public Type asEnclosingSuper(Type t, Symbol sym) {
1435 switch (t.tag) {
1436 case CLASS:
1437 do {
1438 Type s = asSuper(t, sym);
1439 if (s != null) return s;
1440 Type outer = t.getEnclosingType();
1441 t = (outer.tag == CLASS) ? outer :
1442 (t.tsym.owner.enclClass() != null) ? t.tsym.owner.enclClass().type :
1443 Type.noType;
1444 } while (t.tag == CLASS);
1445 return null;
1446 case ARRAY:
1447 return isSubtype(t, sym.type) ? sym.type : null;
1448 case TYPEVAR:
1449 return asSuper(t, sym);
1450 case ERROR:
1451 return t;
1452 default:
1453 return null;
1454 }
1455 }
1456 // </editor-fold>
1458 // <editor-fold defaultstate="collapsed" desc="memberType">
1459 /**
1460 * The type of given symbol, seen as a member of t.
1461 *
1462 * @param t a type
1463 * @param sym a symbol
1464 */
1465 public Type memberType(Type t, Symbol sym) {
1466 return (sym.flags() & STATIC) != 0
1467 ? sym.type
1468 : memberType.visit(t, sym);
1469 }
1470 // where
1471 private SimpleVisitor<Type,Symbol> memberType = new SimpleVisitor<Type,Symbol>() {
1473 public Type visitType(Type t, Symbol sym) {
1474 return sym.type;
1475 }
1477 @Override
1478 public Type visitWildcardType(WildcardType t, Symbol sym) {
1479 return memberType(upperBound(t), sym);
1480 }
1482 @Override
1483 public Type visitClassType(ClassType t, Symbol sym) {
1484 Symbol owner = sym.owner;
1485 long flags = sym.flags();
1486 if (((flags & STATIC) == 0) && owner.type.isParameterized()) {
1487 Type base = asOuterSuper(t, owner);
1488 //if t is an intersection type T = CT & I1 & I2 ... & In
1489 //its supertypes CT, I1, ... In might contain wildcards
1490 //so we need to go through capture conversion
1491 base = t.isCompound() ? capture(base) : base;
1492 if (base != null) {
1493 List<Type> ownerParams = owner.type.allparams();
1494 List<Type> baseParams = base.allparams();
1495 if (ownerParams.nonEmpty()) {
1496 if (baseParams.isEmpty()) {
1497 // then base is a raw type
1498 return erasure(sym.type);
1499 } else {
1500 return subst(sym.type, ownerParams, baseParams);
1501 }
1502 }
1503 }
1504 }
1505 return sym.type;
1506 }
1508 @Override
1509 public Type visitTypeVar(TypeVar t, Symbol sym) {
1510 return memberType(t.bound, sym);
1511 }
1513 @Override
1514 public Type visitErrorType(ErrorType t, Symbol sym) {
1515 return t;
1516 }
1517 };
1518 // </editor-fold>
1520 // <editor-fold defaultstate="collapsed" desc="isAssignable">
1521 public boolean isAssignable(Type t, Type s) {
1522 return isAssignable(t, s, Warner.noWarnings);
1523 }
1525 /**
1526 * Is t assignable to s?<br>
1527 * Equivalent to subtype except for constant values and raw
1528 * types.<br>
1529 * (not defined for Method and ForAll types)
1530 */
1531 public boolean isAssignable(Type t, Type s, Warner warn) {
1532 if (t.tag == ERROR)
1533 return true;
1534 if (t.tag <= INT && t.constValue() != null) {
1535 int value = ((Number)t.constValue()).intValue();
1536 switch (s.tag) {
1537 case BYTE:
1538 if (Byte.MIN_VALUE <= value && value <= Byte.MAX_VALUE)
1539 return true;
1540 break;
1541 case CHAR:
1542 if (Character.MIN_VALUE <= value && value <= Character.MAX_VALUE)
1543 return true;
1544 break;
1545 case SHORT:
1546 if (Short.MIN_VALUE <= value && value <= Short.MAX_VALUE)
1547 return true;
1548 break;
1549 case INT:
1550 return true;
1551 case CLASS:
1552 switch (unboxedType(s).tag) {
1553 case BYTE:
1554 case CHAR:
1555 case SHORT:
1556 return isAssignable(t, unboxedType(s), warn);
1557 }
1558 break;
1559 }
1560 }
1561 return isConvertible(t, s, warn);
1562 }
1563 // </editor-fold>
1565 // <editor-fold defaultstate="collapsed" desc="erasure">
1566 /**
1567 * The erasure of t {@code |t|} -- the type that results when all
1568 * type parameters in t are deleted.
1569 */
1570 public Type erasure(Type t) {
1571 return erasure(t, false);
1572 }
1573 //where
1574 private Type erasure(Type t, boolean recurse) {
1575 if (t.tag <= lastBaseTag)
1576 return t; /* fast special case */
1577 else
1578 return erasure.visit(t, recurse);
1579 }
1580 // where
1581 private SimpleVisitor<Type, Boolean> erasure = new SimpleVisitor<Type, Boolean>() {
1582 public Type visitType(Type t, Boolean recurse) {
1583 if (t.tag <= lastBaseTag)
1584 return t; /*fast special case*/
1585 else
1586 return t.map(recurse ? erasureRecFun : erasureFun);
1587 }
1589 @Override
1590 public Type visitWildcardType(WildcardType t, Boolean recurse) {
1591 return erasure(upperBound(t), recurse);
1592 }
1594 @Override
1595 public Type visitClassType(ClassType t, Boolean recurse) {
1596 Type erased = t.tsym.erasure(Types.this);
1597 if (recurse) {
1598 erased = new ErasedClassType(erased.getEnclosingType(),erased.tsym);
1599 }
1600 return erased;
1601 }
1603 @Override
1604 public Type visitTypeVar(TypeVar t, Boolean recurse) {
1605 return erasure(t.bound, recurse);
1606 }
1608 @Override
1609 public Type visitErrorType(ErrorType t, Boolean recurse) {
1610 return t;
1611 }
1612 };
1614 private Mapping erasureFun = new Mapping ("erasure") {
1615 public Type apply(Type t) { return erasure(t); }
1616 };
1618 private Mapping erasureRecFun = new Mapping ("erasureRecursive") {
1619 public Type apply(Type t) { return erasureRecursive(t); }
1620 };
1622 public List<Type> erasure(List<Type> ts) {
1623 return Type.map(ts, erasureFun);
1624 }
1626 public Type erasureRecursive(Type t) {
1627 return erasure(t, true);
1628 }
1630 public List<Type> erasureRecursive(List<Type> ts) {
1631 return Type.map(ts, erasureRecFun);
1632 }
1633 // </editor-fold>
1635 // <editor-fold defaultstate="collapsed" desc="makeCompoundType">
1636 /**
1637 * Make a compound type from non-empty list of types
1638 *
1639 * @param bounds the types from which the compound type is formed
1640 * @param supertype is objectType if all bounds are interfaces,
1641 * null otherwise.
1642 */
1643 public Type makeCompoundType(List<Type> bounds,
1644 Type supertype) {
1645 ClassSymbol bc =
1646 new ClassSymbol(ABSTRACT|PUBLIC|SYNTHETIC|COMPOUND|ACYCLIC,
1647 Type.moreInfo
1648 ? names.fromString(bounds.toString())
1649 : names.empty,
1650 syms.noSymbol);
1651 if (bounds.head.tag == TYPEVAR)
1652 // error condition, recover
1653 bc.erasure_field = syms.objectType;
1654 else
1655 bc.erasure_field = erasure(bounds.head);
1656 bc.members_field = new Scope(bc);
1657 ClassType bt = (ClassType)bc.type;
1658 bt.allparams_field = List.nil();
1659 if (supertype != null) {
1660 bt.supertype_field = supertype;
1661 bt.interfaces_field = bounds;
1662 } else {
1663 bt.supertype_field = bounds.head;
1664 bt.interfaces_field = bounds.tail;
1665 }
1666 assert bt.supertype_field.tsym.completer != null
1667 || !bt.supertype_field.isInterface()
1668 : bt.supertype_field;
1669 return bt;
1670 }
1672 /**
1673 * Same as {@link #makeCompoundType(List,Type)}, except that the
1674 * second parameter is computed directly. Note that this might
1675 * cause a symbol completion. Hence, this version of
1676 * makeCompoundType may not be called during a classfile read.
1677 */
1678 public Type makeCompoundType(List<Type> bounds) {
1679 Type supertype = (bounds.head.tsym.flags() & INTERFACE) != 0 ?
1680 supertype(bounds.head) : null;
1681 return makeCompoundType(bounds, supertype);
1682 }
1684 /**
1685 * A convenience wrapper for {@link #makeCompoundType(List)}; the
1686 * arguments are converted to a list and passed to the other
1687 * method. Note that this might cause a symbol completion.
1688 * Hence, this version of makeCompoundType may not be called
1689 * during a classfile read.
1690 */
1691 public Type makeCompoundType(Type bound1, Type bound2) {
1692 return makeCompoundType(List.of(bound1, bound2));
1693 }
1694 // </editor-fold>
1696 // <editor-fold defaultstate="collapsed" desc="supertype">
1697 public Type supertype(Type t) {
1698 return supertype.visit(t);
1699 }
1700 // where
1701 private UnaryVisitor<Type> supertype = new UnaryVisitor<Type>() {
1703 public Type visitType(Type t, Void ignored) {
1704 // A note on wildcards: there is no good way to
1705 // determine a supertype for a super bounded wildcard.
1706 return null;
1707 }
1709 @Override
1710 public Type visitClassType(ClassType t, Void ignored) {
1711 if (t.supertype_field == null) {
1712 Type supertype = ((ClassSymbol)t.tsym).getSuperclass();
1713 // An interface has no superclass; its supertype is Object.
1714 if (t.isInterface())
1715 supertype = ((ClassType)t.tsym.type).supertype_field;
1716 if (t.supertype_field == null) {
1717 List<Type> actuals = classBound(t).allparams();
1718 List<Type> formals = t.tsym.type.allparams();
1719 if (t.hasErasedSupertypes()) {
1720 t.supertype_field = erasureRecursive(supertype);
1721 } else if (formals.nonEmpty()) {
1722 t.supertype_field = subst(supertype, formals, actuals);
1723 }
1724 else {
1725 t.supertype_field = supertype;
1726 }
1727 }
1728 }
1729 return t.supertype_field;
1730 }
1732 /**
1733 * The supertype is always a class type. If the type
1734 * variable's bounds start with a class type, this is also
1735 * the supertype. Otherwise, the supertype is
1736 * java.lang.Object.
1737 */
1738 @Override
1739 public Type visitTypeVar(TypeVar t, Void ignored) {
1740 if (t.bound.tag == TYPEVAR ||
1741 (!t.bound.isCompound() && !t.bound.isInterface())) {
1742 return t.bound;
1743 } else {
1744 return supertype(t.bound);
1745 }
1746 }
1748 @Override
1749 public Type visitArrayType(ArrayType t, Void ignored) {
1750 if (t.elemtype.isPrimitive() || isSameType(t.elemtype, syms.objectType))
1751 return arraySuperType();
1752 else
1753 return new ArrayType(supertype(t.elemtype), t.tsym);
1754 }
1756 @Override
1757 public Type visitErrorType(ErrorType t, Void ignored) {
1758 return t;
1759 }
1760 };
1761 // </editor-fold>
1763 // <editor-fold defaultstate="collapsed" desc="interfaces">
1764 /**
1765 * Return the interfaces implemented by this class.
1766 */
1767 public List<Type> interfaces(Type t) {
1768 return interfaces.visit(t);
1769 }
1770 // where
1771 private UnaryVisitor<List<Type>> interfaces = new UnaryVisitor<List<Type>>() {
1773 public List<Type> visitType(Type t, Void ignored) {
1774 return List.nil();
1775 }
1777 @Override
1778 public List<Type> visitClassType(ClassType t, Void ignored) {
1779 if (t.interfaces_field == null) {
1780 List<Type> interfaces = ((ClassSymbol)t.tsym).getInterfaces();
1781 if (t.interfaces_field == null) {
1782 // If t.interfaces_field is null, then t must
1783 // be a parameterized type (not to be confused
1784 // with a generic type declaration).
1785 // Terminology:
1786 // Parameterized type: List<String>
1787 // Generic type declaration: class List<E> { ... }
1788 // So t corresponds to List<String> and
1789 // t.tsym.type corresponds to List<E>.
1790 // The reason t must be parameterized type is
1791 // that completion will happen as a side
1792 // effect of calling
1793 // ClassSymbol.getInterfaces. Since
1794 // t.interfaces_field is null after
1795 // completion, we can assume that t is not the
1796 // type of a class/interface declaration.
1797 assert t != t.tsym.type : t.toString();
1798 List<Type> actuals = t.allparams();
1799 List<Type> formals = t.tsym.type.allparams();
1800 if (t.hasErasedSupertypes()) {
1801 t.interfaces_field = erasureRecursive(interfaces);
1802 } else if (formals.nonEmpty()) {
1803 t.interfaces_field =
1804 upperBounds(subst(interfaces, formals, actuals));
1805 }
1806 else {
1807 t.interfaces_field = interfaces;
1808 }
1809 }
1810 }
1811 return t.interfaces_field;
1812 }
1814 @Override
1815 public List<Type> visitTypeVar(TypeVar t, Void ignored) {
1816 if (t.bound.isCompound())
1817 return interfaces(t.bound);
1819 if (t.bound.isInterface())
1820 return List.of(t.bound);
1822 return List.nil();
1823 }
1824 };
1825 // </editor-fold>
1827 // <editor-fold defaultstate="collapsed" desc="isDerivedRaw">
1828 Map<Type,Boolean> isDerivedRawCache = new HashMap<Type,Boolean>();
1830 public boolean isDerivedRaw(Type t) {
1831 Boolean result = isDerivedRawCache.get(t);
1832 if (result == null) {
1833 result = isDerivedRawInternal(t);
1834 isDerivedRawCache.put(t, result);
1835 }
1836 return result;
1837 }
1839 public boolean isDerivedRawInternal(Type t) {
1840 if (t.isErroneous())
1841 return false;
1842 return
1843 t.isRaw() ||
1844 supertype(t) != null && isDerivedRaw(supertype(t)) ||
1845 isDerivedRaw(interfaces(t));
1846 }
1848 public boolean isDerivedRaw(List<Type> ts) {
1849 List<Type> l = ts;
1850 while (l.nonEmpty() && !isDerivedRaw(l.head)) l = l.tail;
1851 return l.nonEmpty();
1852 }
1853 // </editor-fold>
1855 // <editor-fold defaultstate="collapsed" desc="setBounds">
1856 /**
1857 * Set the bounds field of the given type variable to reflect a
1858 * (possibly multiple) list of bounds.
1859 * @param t a type variable
1860 * @param bounds the bounds, must be nonempty
1861 * @param supertype is objectType if all bounds are interfaces,
1862 * null otherwise.
1863 */
1864 public void setBounds(TypeVar t, List<Type> bounds, Type supertype) {
1865 if (bounds.tail.isEmpty())
1866 t.bound = bounds.head;
1867 else
1868 t.bound = makeCompoundType(bounds, supertype);
1869 t.rank_field = -1;
1870 }
1872 /**
1873 * Same as {@link #setBounds(Type.TypeVar,List,Type)}, except that
1874 * third parameter is computed directly, as follows: if all
1875 * all bounds are interface types, the computed supertype is Object,
1876 * otherwise the supertype is simply left null (in this case, the supertype
1877 * is assumed to be the head of the bound list passed as second argument).
1878 * Note that this check might cause a symbol completion. Hence, this version of
1879 * setBounds may not be called during a classfile read.
1880 */
1881 public void setBounds(TypeVar t, List<Type> bounds) {
1882 Type supertype = (bounds.head.tsym.flags() & INTERFACE) != 0 ?
1883 syms.objectType : null;
1884 setBounds(t, bounds, supertype);
1885 t.rank_field = -1;
1886 }
1887 // </editor-fold>
1889 // <editor-fold defaultstate="collapsed" desc="getBounds">
1890 /**
1891 * Return list of bounds of the given type variable.
1892 */
1893 public List<Type> getBounds(TypeVar t) {
1894 if (t.bound.isErroneous() || !t.bound.isCompound())
1895 return List.of(t.bound);
1896 else if ((erasure(t).tsym.flags() & INTERFACE) == 0)
1897 return interfaces(t).prepend(supertype(t));
1898 else
1899 // No superclass was given in bounds.
1900 // In this case, supertype is Object, erasure is first interface.
1901 return interfaces(t);
1902 }
1903 // </editor-fold>
1905 // <editor-fold defaultstate="collapsed" desc="classBound">
1906 /**
1907 * If the given type is a (possibly selected) type variable,
1908 * return the bounding class of this type, otherwise return the
1909 * type itself.
1910 */
1911 public Type classBound(Type t) {
1912 return classBound.visit(t);
1913 }
1914 // where
1915 private UnaryVisitor<Type> classBound = new UnaryVisitor<Type>() {
1917 public Type visitType(Type t, Void ignored) {
1918 return t;
1919 }
1921 @Override
1922 public Type visitClassType(ClassType t, Void ignored) {
1923 Type outer1 = classBound(t.getEnclosingType());
1924 if (outer1 != t.getEnclosingType())
1925 return new ClassType(outer1, t.getTypeArguments(), t.tsym);
1926 else
1927 return t;
1928 }
1930 @Override
1931 public Type visitTypeVar(TypeVar t, Void ignored) {
1932 return classBound(supertype(t));
1933 }
1935 @Override
1936 public Type visitErrorType(ErrorType t, Void ignored) {
1937 return t;
1938 }
1939 };
1940 // </editor-fold>
1942 // <editor-fold defaultstate="collapsed" desc="sub signature / override equivalence">
1943 /**
1944 * Returns true iff the first signature is a <em>sub
1945 * signature</em> of the other. This is <b>not</b> an equivalence
1946 * relation.
1947 *
1948 * @see "The Java Language Specification, Third Ed. (8.4.2)."
1949 * @see #overrideEquivalent(Type t, Type s)
1950 * @param t first signature (possibly raw).
1951 * @param s second signature (could be subjected to erasure).
1952 * @return true if t is a sub signature of s.
1953 */
1954 public boolean isSubSignature(Type t, Type s) {
1955 return hasSameArgs(t, s) || hasSameArgs(t, erasure(s));
1956 }
1958 /**
1959 * Returns true iff these signatures are related by <em>override
1960 * equivalence</em>. This is the natural extension of
1961 * isSubSignature to an equivalence relation.
1962 *
1963 * @see "The Java Language Specification, Third Ed. (8.4.2)."
1964 * @see #isSubSignature(Type t, Type s)
1965 * @param t a signature (possible raw, could be subjected to
1966 * erasure).
1967 * @param s a signature (possible raw, could be subjected to
1968 * erasure).
1969 * @return true if either argument is a sub signature of the other.
1970 */
1971 public boolean overrideEquivalent(Type t, Type s) {
1972 return hasSameArgs(t, s) ||
1973 hasSameArgs(t, erasure(s)) || hasSameArgs(erasure(t), s);
1974 }
1976 private WeakHashMap<MethodSymbol, SoftReference<Map<TypeSymbol, MethodSymbol>>> implCache_check =
1977 new WeakHashMap<MethodSymbol, SoftReference<Map<TypeSymbol, MethodSymbol>>>();
1979 private WeakHashMap<MethodSymbol, SoftReference<Map<TypeSymbol, MethodSymbol>>> implCache_nocheck =
1980 new WeakHashMap<MethodSymbol, SoftReference<Map<TypeSymbol, MethodSymbol>>>();
1982 public MethodSymbol implementation(MethodSymbol ms, TypeSymbol origin, Types types, boolean checkResult) {
1983 Map<MethodSymbol, SoftReference<Map<TypeSymbol, MethodSymbol>>> implCache = checkResult ?
1984 implCache_check : implCache_nocheck;
1985 SoftReference<Map<TypeSymbol, MethodSymbol>> ref_cache = implCache.get(ms);
1986 Map<TypeSymbol, MethodSymbol> cache = ref_cache != null ? ref_cache.get() : null;
1987 if (cache == null) {
1988 cache = new HashMap<TypeSymbol, MethodSymbol>();
1989 implCache.put(ms, new SoftReference<Map<TypeSymbol, MethodSymbol>>(cache));
1990 }
1991 MethodSymbol impl = cache.get(origin);
1992 if (impl == null) {
1993 for (Type t = origin.type; t.tag == CLASS || t.tag == TYPEVAR; t = types.supertype(t)) {
1994 while (t.tag == TYPEVAR)
1995 t = t.getUpperBound();
1996 TypeSymbol c = t.tsym;
1997 for (Scope.Entry e = c.members().lookup(ms.name);
1998 e.scope != null;
1999 e = e.next()) {
2000 if (e.sym.kind == Kinds.MTH) {
2001 MethodSymbol m = (MethodSymbol) e.sym;
2002 if (m.overrides(ms, origin, types, checkResult) &&
2003 (m.flags() & SYNTHETIC) == 0) {
2004 impl = m;
2005 cache.put(origin, m);
2006 return impl;
2007 }
2008 }
2009 }
2010 }
2011 }
2012 return impl;
2013 }
2015 /**
2016 * Does t have the same arguments as s? It is assumed that both
2017 * types are (possibly polymorphic) method types. Monomorphic
2018 * method types "have the same arguments", if their argument lists
2019 * are equal. Polymorphic method types "have the same arguments",
2020 * if they have the same arguments after renaming all type
2021 * variables of one to corresponding type variables in the other,
2022 * where correspondence is by position in the type parameter list.
2023 */
2024 public boolean hasSameArgs(Type t, Type s) {
2025 return hasSameArgs.visit(t, s);
2026 }
2027 // where
2028 private TypeRelation hasSameArgs = new TypeRelation() {
2030 public Boolean visitType(Type t, Type s) {
2031 throw new AssertionError();
2032 }
2034 @Override
2035 public Boolean visitMethodType(MethodType t, Type s) {
2036 return s.tag == METHOD
2037 && containsTypeEquivalent(t.argtypes, s.getParameterTypes());
2038 }
2040 @Override
2041 public Boolean visitForAll(ForAll t, Type s) {
2042 if (s.tag != FORALL)
2043 return false;
2045 ForAll forAll = (ForAll)s;
2046 return hasSameBounds(t, forAll)
2047 && visit(t.qtype, subst(forAll.qtype, forAll.tvars, t.tvars));
2048 }
2050 @Override
2051 public Boolean visitErrorType(ErrorType t, Type s) {
2052 return false;
2053 }
2054 };
2055 // </editor-fold>
2057 // <editor-fold defaultstate="collapsed" desc="subst">
2058 public List<Type> subst(List<Type> ts,
2059 List<Type> from,
2060 List<Type> to) {
2061 return new Subst(from, to).subst(ts);
2062 }
2064 /**
2065 * Substitute all occurrences of a type in `from' with the
2066 * corresponding type in `to' in 't'. Match lists `from' and `to'
2067 * from the right: If lists have different length, discard leading
2068 * elements of the longer list.
2069 */
2070 public Type subst(Type t, List<Type> from, List<Type> to) {
2071 return new Subst(from, to).subst(t);
2072 }
2074 private class Subst extends UnaryVisitor<Type> {
2075 List<Type> from;
2076 List<Type> to;
2078 public Subst(List<Type> from, List<Type> to) {
2079 int fromLength = from.length();
2080 int toLength = to.length();
2081 while (fromLength > toLength) {
2082 fromLength--;
2083 from = from.tail;
2084 }
2085 while (fromLength < toLength) {
2086 toLength--;
2087 to = to.tail;
2088 }
2089 this.from = from;
2090 this.to = to;
2091 }
2093 Type subst(Type t) {
2094 if (from.tail == null)
2095 return t;
2096 else
2097 return visit(t);
2098 }
2100 List<Type> subst(List<Type> ts) {
2101 if (from.tail == null)
2102 return ts;
2103 boolean wild = false;
2104 if (ts.nonEmpty() && from.nonEmpty()) {
2105 Type head1 = subst(ts.head);
2106 List<Type> tail1 = subst(ts.tail);
2107 if (head1 != ts.head || tail1 != ts.tail)
2108 return tail1.prepend(head1);
2109 }
2110 return ts;
2111 }
2113 public Type visitType(Type t, Void ignored) {
2114 return t;
2115 }
2117 @Override
2118 public Type visitMethodType(MethodType t, Void ignored) {
2119 List<Type> argtypes = subst(t.argtypes);
2120 Type restype = subst(t.restype);
2121 List<Type> thrown = subst(t.thrown);
2122 if (argtypes == t.argtypes &&
2123 restype == t.restype &&
2124 thrown == t.thrown)
2125 return t;
2126 else
2127 return new MethodType(argtypes, restype, thrown, t.tsym);
2128 }
2130 @Override
2131 public Type visitTypeVar(TypeVar t, Void ignored) {
2132 for (List<Type> from = this.from, to = this.to;
2133 from.nonEmpty();
2134 from = from.tail, to = to.tail) {
2135 if (t == from.head) {
2136 return to.head.withTypeVar(t);
2137 }
2138 }
2139 return t;
2140 }
2142 @Override
2143 public Type visitClassType(ClassType t, Void ignored) {
2144 if (!t.isCompound()) {
2145 List<Type> typarams = t.getTypeArguments();
2146 List<Type> typarams1 = subst(typarams);
2147 Type outer = t.getEnclosingType();
2148 Type outer1 = subst(outer);
2149 if (typarams1 == typarams && outer1 == outer)
2150 return t;
2151 else
2152 return new ClassType(outer1, typarams1, t.tsym);
2153 } else {
2154 Type st = subst(supertype(t));
2155 List<Type> is = upperBounds(subst(interfaces(t)));
2156 if (st == supertype(t) && is == interfaces(t))
2157 return t;
2158 else
2159 return makeCompoundType(is.prepend(st));
2160 }
2161 }
2163 @Override
2164 public Type visitWildcardType(WildcardType t, Void ignored) {
2165 Type bound = t.type;
2166 if (t.kind != BoundKind.UNBOUND)
2167 bound = subst(bound);
2168 if (bound == t.type) {
2169 return t;
2170 } else {
2171 if (t.isExtendsBound() && bound.isExtendsBound())
2172 bound = upperBound(bound);
2173 return new WildcardType(bound, t.kind, syms.boundClass, t.bound);
2174 }
2175 }
2177 @Override
2178 public Type visitArrayType(ArrayType t, Void ignored) {
2179 Type elemtype = subst(t.elemtype);
2180 if (elemtype == t.elemtype)
2181 return t;
2182 else
2183 return new ArrayType(upperBound(elemtype), t.tsym);
2184 }
2186 @Override
2187 public Type visitForAll(ForAll t, Void ignored) {
2188 List<Type> tvars1 = substBounds(t.tvars, from, to);
2189 Type qtype1 = subst(t.qtype);
2190 if (tvars1 == t.tvars && qtype1 == t.qtype) {
2191 return t;
2192 } else if (tvars1 == t.tvars) {
2193 return new ForAll(tvars1, qtype1);
2194 } else {
2195 return new ForAll(tvars1, Types.this.subst(qtype1, t.tvars, tvars1));
2196 }
2197 }
2199 @Override
2200 public Type visitErrorType(ErrorType t, Void ignored) {
2201 return t;
2202 }
2203 }
2205 public List<Type> substBounds(List<Type> tvars,
2206 List<Type> from,
2207 List<Type> to) {
2208 if (tvars.isEmpty())
2209 return tvars;
2210 ListBuffer<Type> newBoundsBuf = lb();
2211 boolean changed = false;
2212 // calculate new bounds
2213 for (Type t : tvars) {
2214 TypeVar tv = (TypeVar) t;
2215 Type bound = subst(tv.bound, from, to);
2216 if (bound != tv.bound)
2217 changed = true;
2218 newBoundsBuf.append(bound);
2219 }
2220 if (!changed)
2221 return tvars;
2222 ListBuffer<Type> newTvars = lb();
2223 // create new type variables without bounds
2224 for (Type t : tvars) {
2225 newTvars.append(new TypeVar(t.tsym, null, syms.botType));
2226 }
2227 // the new bounds should use the new type variables in place
2228 // of the old
2229 List<Type> newBounds = newBoundsBuf.toList();
2230 from = tvars;
2231 to = newTvars.toList();
2232 for (; !newBounds.isEmpty(); newBounds = newBounds.tail) {
2233 newBounds.head = subst(newBounds.head, from, to);
2234 }
2235 newBounds = newBoundsBuf.toList();
2236 // set the bounds of new type variables to the new bounds
2237 for (Type t : newTvars.toList()) {
2238 TypeVar tv = (TypeVar) t;
2239 tv.bound = newBounds.head;
2240 newBounds = newBounds.tail;
2241 }
2242 return newTvars.toList();
2243 }
2245 public TypeVar substBound(TypeVar t, List<Type> from, List<Type> to) {
2246 Type bound1 = subst(t.bound, from, to);
2247 if (bound1 == t.bound)
2248 return t;
2249 else {
2250 // create new type variable without bounds
2251 TypeVar tv = new TypeVar(t.tsym, null, syms.botType);
2252 // the new bound should use the new type variable in place
2253 // of the old
2254 tv.bound = subst(bound1, List.<Type>of(t), List.<Type>of(tv));
2255 return tv;
2256 }
2257 }
2258 // </editor-fold>
2260 // <editor-fold defaultstate="collapsed" desc="hasSameBounds">
2261 /**
2262 * Does t have the same bounds for quantified variables as s?
2263 */
2264 boolean hasSameBounds(ForAll t, ForAll s) {
2265 List<Type> l1 = t.tvars;
2266 List<Type> l2 = s.tvars;
2267 while (l1.nonEmpty() && l2.nonEmpty() &&
2268 isSameType(l1.head.getUpperBound(),
2269 subst(l2.head.getUpperBound(),
2270 s.tvars,
2271 t.tvars))) {
2272 l1 = l1.tail;
2273 l2 = l2.tail;
2274 }
2275 return l1.isEmpty() && l2.isEmpty();
2276 }
2277 // </editor-fold>
2279 // <editor-fold defaultstate="collapsed" desc="newInstances">
2280 /** Create new vector of type variables from list of variables
2281 * changing all recursive bounds from old to new list.
2282 */
2283 public List<Type> newInstances(List<Type> tvars) {
2284 List<Type> tvars1 = Type.map(tvars, newInstanceFun);
2285 for (List<Type> l = tvars1; l.nonEmpty(); l = l.tail) {
2286 TypeVar tv = (TypeVar) l.head;
2287 tv.bound = subst(tv.bound, tvars, tvars1);
2288 }
2289 return tvars1;
2290 }
2291 static private Mapping newInstanceFun = new Mapping("newInstanceFun") {
2292 public Type apply(Type t) { return new TypeVar(t.tsym, t.getUpperBound(), t.getLowerBound()); }
2293 };
2294 // </editor-fold>
2296 // <editor-fold defaultstate="collapsed" desc="createErrorType">
2297 public Type createErrorType(Type originalType) {
2298 return new ErrorType(originalType, syms.errSymbol);
2299 }
2301 public Type createErrorType(ClassSymbol c, Type originalType) {
2302 return new ErrorType(c, originalType);
2303 }
2305 public Type createErrorType(Name name, TypeSymbol container, Type originalType) {
2306 return new ErrorType(name, container, originalType);
2307 }
2308 // </editor-fold>
2310 // <editor-fold defaultstate="collapsed" desc="rank">
2311 /**
2312 * The rank of a class is the length of the longest path between
2313 * the class and java.lang.Object in the class inheritance
2314 * graph. Undefined for all but reference types.
2315 */
2316 public int rank(Type t) {
2317 switch(t.tag) {
2318 case CLASS: {
2319 ClassType cls = (ClassType)t;
2320 if (cls.rank_field < 0) {
2321 Name fullname = cls.tsym.getQualifiedName();
2322 if (fullname == names.java_lang_Object)
2323 cls.rank_field = 0;
2324 else {
2325 int r = rank(supertype(cls));
2326 for (List<Type> l = interfaces(cls);
2327 l.nonEmpty();
2328 l = l.tail) {
2329 if (rank(l.head) > r)
2330 r = rank(l.head);
2331 }
2332 cls.rank_field = r + 1;
2333 }
2334 }
2335 return cls.rank_field;
2336 }
2337 case TYPEVAR: {
2338 TypeVar tvar = (TypeVar)t;
2339 if (tvar.rank_field < 0) {
2340 int r = rank(supertype(tvar));
2341 for (List<Type> l = interfaces(tvar);
2342 l.nonEmpty();
2343 l = l.tail) {
2344 if (rank(l.head) > r) r = rank(l.head);
2345 }
2346 tvar.rank_field = r + 1;
2347 }
2348 return tvar.rank_field;
2349 }
2350 case ERROR:
2351 return 0;
2352 default:
2353 throw new AssertionError();
2354 }
2355 }
2356 // </editor-fold>
2358 /**
2359 * Helper method for generating a string representation of a given type
2360 * accordingly to a given locale
2361 */
2362 public String toString(Type t, Locale locale) {
2363 return Printer.createStandardPrinter(messages).visit(t, locale);
2364 }
2366 /**
2367 * Helper method for generating a string representation of a given type
2368 * accordingly to a given locale
2369 */
2370 public String toString(Symbol t, Locale locale) {
2371 return Printer.createStandardPrinter(messages).visit(t, locale);
2372 }
2374 // <editor-fold defaultstate="collapsed" desc="toString">
2375 /**
2376 * This toString is slightly more descriptive than the one on Type.
2377 *
2378 * @deprecated Types.toString(Type t, Locale l) provides better support
2379 * for localization
2380 */
2381 @Deprecated
2382 public String toString(Type t) {
2383 if (t.tag == FORALL) {
2384 ForAll forAll = (ForAll)t;
2385 return typaramsString(forAll.tvars) + forAll.qtype;
2386 }
2387 return "" + t;
2388 }
2389 // where
2390 private String typaramsString(List<Type> tvars) {
2391 StringBuffer s = new StringBuffer();
2392 s.append('<');
2393 boolean first = true;
2394 for (Type t : tvars) {
2395 if (!first) s.append(", ");
2396 first = false;
2397 appendTyparamString(((TypeVar)t), s);
2398 }
2399 s.append('>');
2400 return s.toString();
2401 }
2402 private void appendTyparamString(TypeVar t, StringBuffer buf) {
2403 buf.append(t);
2404 if (t.bound == null ||
2405 t.bound.tsym.getQualifiedName() == names.java_lang_Object)
2406 return;
2407 buf.append(" extends "); // Java syntax; no need for i18n
2408 Type bound = t.bound;
2409 if (!bound.isCompound()) {
2410 buf.append(bound);
2411 } else if ((erasure(t).tsym.flags() & INTERFACE) == 0) {
2412 buf.append(supertype(t));
2413 for (Type intf : interfaces(t)) {
2414 buf.append('&');
2415 buf.append(intf);
2416 }
2417 } else {
2418 // No superclass was given in bounds.
2419 // In this case, supertype is Object, erasure is first interface.
2420 boolean first = true;
2421 for (Type intf : interfaces(t)) {
2422 if (!first) buf.append('&');
2423 first = false;
2424 buf.append(intf);
2425 }
2426 }
2427 }
2428 // </editor-fold>
2430 // <editor-fold defaultstate="collapsed" desc="Determining least upper bounds of types">
2431 /**
2432 * A cache for closures.
2433 *
2434 * <p>A closure is a list of all the supertypes and interfaces of
2435 * a class or interface type, ordered by ClassSymbol.precedes
2436 * (that is, subclasses come first, arbitrary but fixed
2437 * otherwise).
2438 */
2439 private Map<Type,List<Type>> closureCache = new HashMap<Type,List<Type>>();
2441 /**
2442 * Returns the closure of a class or interface type.
2443 */
2444 public List<Type> closure(Type t) {
2445 List<Type> cl = closureCache.get(t);
2446 if (cl == null) {
2447 Type st = supertype(t);
2448 if (!t.isCompound()) {
2449 if (st.tag == CLASS) {
2450 cl = insert(closure(st), t);
2451 } else if (st.tag == TYPEVAR) {
2452 cl = closure(st).prepend(t);
2453 } else {
2454 cl = List.of(t);
2455 }
2456 } else {
2457 cl = closure(supertype(t));
2458 }
2459 for (List<Type> l = interfaces(t); l.nonEmpty(); l = l.tail)
2460 cl = union(cl, closure(l.head));
2461 closureCache.put(t, cl);
2462 }
2463 return cl;
2464 }
2466 /**
2467 * Insert a type in a closure
2468 */
2469 public List<Type> insert(List<Type> cl, Type t) {
2470 if (cl.isEmpty() || t.tsym.precedes(cl.head.tsym, this)) {
2471 return cl.prepend(t);
2472 } else if (cl.head.tsym.precedes(t.tsym, this)) {
2473 return insert(cl.tail, t).prepend(cl.head);
2474 } else {
2475 return cl;
2476 }
2477 }
2479 /**
2480 * Form the union of two closures
2481 */
2482 public List<Type> union(List<Type> cl1, List<Type> cl2) {
2483 if (cl1.isEmpty()) {
2484 return cl2;
2485 } else if (cl2.isEmpty()) {
2486 return cl1;
2487 } else if (cl1.head.tsym.precedes(cl2.head.tsym, this)) {
2488 return union(cl1.tail, cl2).prepend(cl1.head);
2489 } else if (cl2.head.tsym.precedes(cl1.head.tsym, this)) {
2490 return union(cl1, cl2.tail).prepend(cl2.head);
2491 } else {
2492 return union(cl1.tail, cl2.tail).prepend(cl1.head);
2493 }
2494 }
2496 /**
2497 * Intersect two closures
2498 */
2499 public List<Type> intersect(List<Type> cl1, List<Type> cl2) {
2500 if (cl1 == cl2)
2501 return cl1;
2502 if (cl1.isEmpty() || cl2.isEmpty())
2503 return List.nil();
2504 if (cl1.head.tsym.precedes(cl2.head.tsym, this))
2505 return intersect(cl1.tail, cl2);
2506 if (cl2.head.tsym.precedes(cl1.head.tsym, this))
2507 return intersect(cl1, cl2.tail);
2508 if (isSameType(cl1.head, cl2.head))
2509 return intersect(cl1.tail, cl2.tail).prepend(cl1.head);
2510 if (cl1.head.tsym == cl2.head.tsym &&
2511 cl1.head.tag == CLASS && cl2.head.tag == CLASS) {
2512 if (cl1.head.isParameterized() && cl2.head.isParameterized()) {
2513 Type merge = merge(cl1.head,cl2.head);
2514 return intersect(cl1.tail, cl2.tail).prepend(merge);
2515 }
2516 if (cl1.head.isRaw() || cl2.head.isRaw())
2517 return intersect(cl1.tail, cl2.tail).prepend(erasure(cl1.head));
2518 }
2519 return intersect(cl1.tail, cl2.tail);
2520 }
2521 // where
2522 class TypePair {
2523 final Type t1;
2524 final Type t2;
2525 TypePair(Type t1, Type t2) {
2526 this.t1 = t1;
2527 this.t2 = t2;
2528 }
2529 @Override
2530 public int hashCode() {
2531 return 127 * Types.hashCode(t1) + Types.hashCode(t2);
2532 }
2533 @Override
2534 public boolean equals(Object obj) {
2535 if (!(obj instanceof TypePair))
2536 return false;
2537 TypePair typePair = (TypePair)obj;
2538 return isSameType(t1, typePair.t1)
2539 && isSameType(t2, typePair.t2);
2540 }
2541 }
2542 Set<TypePair> mergeCache = new HashSet<TypePair>();
2543 private Type merge(Type c1, Type c2) {
2544 ClassType class1 = (ClassType) c1;
2545 List<Type> act1 = class1.getTypeArguments();
2546 ClassType class2 = (ClassType) c2;
2547 List<Type> act2 = class2.getTypeArguments();
2548 ListBuffer<Type> merged = new ListBuffer<Type>();
2549 List<Type> typarams = class1.tsym.type.getTypeArguments();
2551 while (act1.nonEmpty() && act2.nonEmpty() && typarams.nonEmpty()) {
2552 if (containsType(act1.head, act2.head)) {
2553 merged.append(act1.head);
2554 } else if (containsType(act2.head, act1.head)) {
2555 merged.append(act2.head);
2556 } else {
2557 TypePair pair = new TypePair(c1, c2);
2558 Type m;
2559 if (mergeCache.add(pair)) {
2560 m = new WildcardType(lub(upperBound(act1.head),
2561 upperBound(act2.head)),
2562 BoundKind.EXTENDS,
2563 syms.boundClass);
2564 mergeCache.remove(pair);
2565 } else {
2566 m = new WildcardType(syms.objectType,
2567 BoundKind.UNBOUND,
2568 syms.boundClass);
2569 }
2570 merged.append(m.withTypeVar(typarams.head));
2571 }
2572 act1 = act1.tail;
2573 act2 = act2.tail;
2574 typarams = typarams.tail;
2575 }
2576 assert(act1.isEmpty() && act2.isEmpty() && typarams.isEmpty());
2577 return new ClassType(class1.getEnclosingType(), merged.toList(), class1.tsym);
2578 }
2580 /**
2581 * Return the minimum type of a closure, a compound type if no
2582 * unique minimum exists.
2583 */
2584 private Type compoundMin(List<Type> cl) {
2585 if (cl.isEmpty()) return syms.objectType;
2586 List<Type> compound = closureMin(cl);
2587 if (compound.isEmpty())
2588 return null;
2589 else if (compound.tail.isEmpty())
2590 return compound.head;
2591 else
2592 return makeCompoundType(compound);
2593 }
2595 /**
2596 * Return the minimum types of a closure, suitable for computing
2597 * compoundMin or glb.
2598 */
2599 private List<Type> closureMin(List<Type> cl) {
2600 ListBuffer<Type> classes = lb();
2601 ListBuffer<Type> interfaces = lb();
2602 while (!cl.isEmpty()) {
2603 Type current = cl.head;
2604 if (current.isInterface())
2605 interfaces.append(current);
2606 else
2607 classes.append(current);
2608 ListBuffer<Type> candidates = lb();
2609 for (Type t : cl.tail) {
2610 if (!isSubtypeNoCapture(current, t))
2611 candidates.append(t);
2612 }
2613 cl = candidates.toList();
2614 }
2615 return classes.appendList(interfaces).toList();
2616 }
2618 /**
2619 * Return the least upper bound of pair of types. if the lub does
2620 * not exist return null.
2621 */
2622 public Type lub(Type t1, Type t2) {
2623 return lub(List.of(t1, t2));
2624 }
2626 /**
2627 * Return the least upper bound (lub) of set of types. If the lub
2628 * does not exist return the type of null (bottom).
2629 */
2630 public Type lub(List<Type> ts) {
2631 final int ARRAY_BOUND = 1;
2632 final int CLASS_BOUND = 2;
2633 int boundkind = 0;
2634 for (Type t : ts) {
2635 switch (t.tag) {
2636 case CLASS:
2637 boundkind |= CLASS_BOUND;
2638 break;
2639 case ARRAY:
2640 boundkind |= ARRAY_BOUND;
2641 break;
2642 case TYPEVAR:
2643 do {
2644 t = t.getUpperBound();
2645 } while (t.tag == TYPEVAR);
2646 if (t.tag == ARRAY) {
2647 boundkind |= ARRAY_BOUND;
2648 } else {
2649 boundkind |= CLASS_BOUND;
2650 }
2651 break;
2652 default:
2653 if (t.isPrimitive())
2654 return syms.errType;
2655 }
2656 }
2657 switch (boundkind) {
2658 case 0:
2659 return syms.botType;
2661 case ARRAY_BOUND:
2662 // calculate lub(A[], B[])
2663 List<Type> elements = Type.map(ts, elemTypeFun);
2664 for (Type t : elements) {
2665 if (t.isPrimitive()) {
2666 // if a primitive type is found, then return
2667 // arraySuperType unless all the types are the
2668 // same
2669 Type first = ts.head;
2670 for (Type s : ts.tail) {
2671 if (!isSameType(first, s)) {
2672 // lub(int[], B[]) is Cloneable & Serializable
2673 return arraySuperType();
2674 }
2675 }
2676 // all the array types are the same, return one
2677 // lub(int[], int[]) is int[]
2678 return first;
2679 }
2680 }
2681 // lub(A[], B[]) is lub(A, B)[]
2682 return new ArrayType(lub(elements), syms.arrayClass);
2684 case CLASS_BOUND:
2685 // calculate lub(A, B)
2686 while (ts.head.tag != CLASS && ts.head.tag != TYPEVAR)
2687 ts = ts.tail;
2688 assert !ts.isEmpty();
2689 List<Type> cl = closure(ts.head);
2690 for (Type t : ts.tail) {
2691 if (t.tag == CLASS || t.tag == TYPEVAR)
2692 cl = intersect(cl, closure(t));
2693 }
2694 return compoundMin(cl);
2696 default:
2697 // calculate lub(A, B[])
2698 List<Type> classes = List.of(arraySuperType());
2699 for (Type t : ts) {
2700 if (t.tag != ARRAY) // Filter out any arrays
2701 classes = classes.prepend(t);
2702 }
2703 // lub(A, B[]) is lub(A, arraySuperType)
2704 return lub(classes);
2705 }
2706 }
2707 // where
2708 private Type arraySuperType = null;
2709 private Type arraySuperType() {
2710 // initialized lazily to avoid problems during compiler startup
2711 if (arraySuperType == null) {
2712 synchronized (this) {
2713 if (arraySuperType == null) {
2714 // JLS 10.8: all arrays implement Cloneable and Serializable.
2715 arraySuperType = makeCompoundType(List.of(syms.serializableType,
2716 syms.cloneableType),
2717 syms.objectType);
2718 }
2719 }
2720 }
2721 return arraySuperType;
2722 }
2723 // </editor-fold>
2725 // <editor-fold defaultstate="collapsed" desc="Greatest lower bound">
2726 public Type glb(List<Type> ts) {
2727 Type t1 = ts.head;
2728 for (Type t2 : ts.tail) {
2729 if (t1.isErroneous())
2730 return t1;
2731 t1 = glb(t1, t2);
2732 }
2733 return t1;
2734 }
2735 //where
2736 public Type glb(Type t, Type s) {
2737 if (s == null)
2738 return t;
2739 else if (isSubtypeNoCapture(t, s))
2740 return t;
2741 else if (isSubtypeNoCapture(s, t))
2742 return s;
2744 List<Type> closure = union(closure(t), closure(s));
2745 List<Type> bounds = closureMin(closure);
2747 if (bounds.isEmpty()) { // length == 0
2748 return syms.objectType;
2749 } else if (bounds.tail.isEmpty()) { // length == 1
2750 return bounds.head;
2751 } else { // length > 1
2752 int classCount = 0;
2753 for (Type bound : bounds)
2754 if (!bound.isInterface())
2755 classCount++;
2756 if (classCount > 1)
2757 return createErrorType(t);
2758 }
2759 return makeCompoundType(bounds);
2760 }
2761 // </editor-fold>
2763 // <editor-fold defaultstate="collapsed" desc="hashCode">
2764 /**
2765 * Compute a hash code on a type.
2766 */
2767 public static int hashCode(Type t) {
2768 return hashCode.visit(t);
2769 }
2770 // where
2771 private static final UnaryVisitor<Integer> hashCode = new UnaryVisitor<Integer>() {
2773 public Integer visitType(Type t, Void ignored) {
2774 return t.tag;
2775 }
2777 @Override
2778 public Integer visitClassType(ClassType t, Void ignored) {
2779 int result = visit(t.getEnclosingType());
2780 result *= 127;
2781 result += t.tsym.flatName().hashCode();
2782 for (Type s : t.getTypeArguments()) {
2783 result *= 127;
2784 result += visit(s);
2785 }
2786 return result;
2787 }
2789 @Override
2790 public Integer visitWildcardType(WildcardType t, Void ignored) {
2791 int result = t.kind.hashCode();
2792 if (t.type != null) {
2793 result *= 127;
2794 result += visit(t.type);
2795 }
2796 return result;
2797 }
2799 @Override
2800 public Integer visitArrayType(ArrayType t, Void ignored) {
2801 return visit(t.elemtype) + 12;
2802 }
2804 @Override
2805 public Integer visitTypeVar(TypeVar t, Void ignored) {
2806 return System.identityHashCode(t.tsym);
2807 }
2809 @Override
2810 public Integer visitUndetVar(UndetVar t, Void ignored) {
2811 return System.identityHashCode(t);
2812 }
2814 @Override
2815 public Integer visitErrorType(ErrorType t, Void ignored) {
2816 return 0;
2817 }
2818 };
2819 // </editor-fold>
2821 // <editor-fold defaultstate="collapsed" desc="Return-Type-Substitutable">
2822 /**
2823 * Does t have a result that is a subtype of the result type of s,
2824 * suitable for covariant returns? It is assumed that both types
2825 * are (possibly polymorphic) method types. Monomorphic method
2826 * types are handled in the obvious way. Polymorphic method types
2827 * require renaming all type variables of one to corresponding
2828 * type variables in the other, where correspondence is by
2829 * position in the type parameter list. */
2830 public boolean resultSubtype(Type t, Type s, Warner warner) {
2831 List<Type> tvars = t.getTypeArguments();
2832 List<Type> svars = s.getTypeArguments();
2833 Type tres = t.getReturnType();
2834 Type sres = subst(s.getReturnType(), svars, tvars);
2835 return covariantReturnType(tres, sres, warner);
2836 }
2838 /**
2839 * Return-Type-Substitutable.
2840 * @see <a href="http://java.sun.com/docs/books/jls/">The Java
2841 * Language Specification, Third Ed. (8.4.5)</a>
2842 */
2843 public boolean returnTypeSubstitutable(Type r1, Type r2) {
2844 if (hasSameArgs(r1, r2))
2845 return resultSubtype(r1, r2, Warner.noWarnings);
2846 else
2847 return covariantReturnType(r1.getReturnType(),
2848 erasure(r2.getReturnType()),
2849 Warner.noWarnings);
2850 }
2852 public boolean returnTypeSubstitutable(Type r1,
2853 Type r2, Type r2res,
2854 Warner warner) {
2855 if (isSameType(r1.getReturnType(), r2res))
2856 return true;
2857 if (r1.getReturnType().isPrimitive() || r2res.isPrimitive())
2858 return false;
2860 if (hasSameArgs(r1, r2))
2861 return covariantReturnType(r1.getReturnType(), r2res, warner);
2862 if (!source.allowCovariantReturns())
2863 return false;
2864 if (isSubtypeUnchecked(r1.getReturnType(), r2res, warner))
2865 return true;
2866 if (!isSubtype(r1.getReturnType(), erasure(r2res)))
2867 return false;
2868 warner.warnUnchecked();
2869 return true;
2870 }
2872 /**
2873 * Is t an appropriate return type in an overrider for a
2874 * method that returns s?
2875 */
2876 public boolean covariantReturnType(Type t, Type s, Warner warner) {
2877 return
2878 isSameType(t, s) ||
2879 source.allowCovariantReturns() &&
2880 !t.isPrimitive() &&
2881 !s.isPrimitive() &&
2882 isAssignable(t, s, warner);
2883 }
2884 // </editor-fold>
2886 // <editor-fold defaultstate="collapsed" desc="Box/unbox support">
2887 /**
2888 * Return the class that boxes the given primitive.
2889 */
2890 public ClassSymbol boxedClass(Type t) {
2891 return reader.enterClass(syms.boxedName[t.tag]);
2892 }
2894 /**
2895 * Return the primitive type corresponding to a boxed type.
2896 */
2897 public Type unboxedType(Type t) {
2898 if (allowBoxing) {
2899 for (int i=0; i<syms.boxedName.length; i++) {
2900 Name box = syms.boxedName[i];
2901 if (box != null &&
2902 asSuper(t, reader.enterClass(box)) != null)
2903 return syms.typeOfTag[i];
2904 }
2905 }
2906 return Type.noType;
2907 }
2908 // </editor-fold>
2910 // <editor-fold defaultstate="collapsed" desc="Capture conversion">
2911 /*
2912 * JLS 3rd Ed. 5.1.10 Capture Conversion:
2913 *
2914 * Let G name a generic type declaration with n formal type
2915 * parameters A1 ... An with corresponding bounds U1 ... Un. There
2916 * exists a capture conversion from G<T1 ... Tn> to G<S1 ... Sn>,
2917 * where, for 1 <= i <= n:
2918 *
2919 * + If Ti is a wildcard type argument (4.5.1) of the form ? then
2920 * Si is a fresh type variable whose upper bound is
2921 * Ui[A1 := S1, ..., An := Sn] and whose lower bound is the null
2922 * type.
2923 *
2924 * + If Ti is a wildcard type argument of the form ? extends Bi,
2925 * then Si is a fresh type variable whose upper bound is
2926 * glb(Bi, Ui[A1 := S1, ..., An := Sn]) and whose lower bound is
2927 * the null type, where glb(V1,... ,Vm) is V1 & ... & Vm. It is
2928 * a compile-time error if for any two classes (not interfaces)
2929 * Vi and Vj,Vi is not a subclass of Vj or vice versa.
2930 *
2931 * + If Ti is a wildcard type argument of the form ? super Bi,
2932 * then Si is a fresh type variable whose upper bound is
2933 * Ui[A1 := S1, ..., An := Sn] and whose lower bound is Bi.
2934 *
2935 * + Otherwise, Si = Ti.
2936 *
2937 * Capture conversion on any type other than a parameterized type
2938 * (4.5) acts as an identity conversion (5.1.1). Capture
2939 * conversions never require a special action at run time and
2940 * therefore never throw an exception at run time.
2941 *
2942 * Capture conversion is not applied recursively.
2943 */
2944 /**
2945 * Capture conversion as specified by JLS 3rd Ed.
2946 */
2948 public List<Type> capture(List<Type> ts) {
2949 List<Type> buf = List.nil();
2950 for (Type t : ts) {
2951 buf = buf.prepend(capture(t));
2952 }
2953 return buf.reverse();
2954 }
2955 public Type capture(Type t) {
2956 if (t.tag != CLASS)
2957 return t;
2958 if (t.getEnclosingType() != Type.noType) {
2959 Type capturedEncl = capture(t.getEnclosingType());
2960 if (capturedEncl != t.getEnclosingType()) {
2961 Type type1 = memberType(capturedEncl, t.tsym);
2962 t = subst(type1, t.tsym.type.getTypeArguments(), t.getTypeArguments());
2963 }
2964 }
2965 ClassType cls = (ClassType)t;
2966 if (cls.isRaw() || !cls.isParameterized())
2967 return cls;
2969 ClassType G = (ClassType)cls.asElement().asType();
2970 List<Type> A = G.getTypeArguments();
2971 List<Type> T = cls.getTypeArguments();
2972 List<Type> S = freshTypeVariables(T);
2974 List<Type> currentA = A;
2975 List<Type> currentT = T;
2976 List<Type> currentS = S;
2977 boolean captured = false;
2978 while (!currentA.isEmpty() &&
2979 !currentT.isEmpty() &&
2980 !currentS.isEmpty()) {
2981 if (currentS.head != currentT.head) {
2982 captured = true;
2983 WildcardType Ti = (WildcardType)currentT.head;
2984 Type Ui = currentA.head.getUpperBound();
2985 CapturedType Si = (CapturedType)currentS.head;
2986 if (Ui == null)
2987 Ui = syms.objectType;
2988 switch (Ti.kind) {
2989 case UNBOUND:
2990 Si.bound = subst(Ui, A, S);
2991 Si.lower = syms.botType;
2992 break;
2993 case EXTENDS:
2994 Si.bound = glb(Ti.getExtendsBound(), subst(Ui, A, S));
2995 Si.lower = syms.botType;
2996 break;
2997 case SUPER:
2998 Si.bound = subst(Ui, A, S);
2999 Si.lower = Ti.getSuperBound();
3000 break;
3001 }
3002 if (Si.bound == Si.lower)
3003 currentS.head = Si.bound;
3004 }
3005 currentA = currentA.tail;
3006 currentT = currentT.tail;
3007 currentS = currentS.tail;
3008 }
3009 if (!currentA.isEmpty() || !currentT.isEmpty() || !currentS.isEmpty())
3010 return erasure(t); // some "rare" type involved
3012 if (captured)
3013 return new ClassType(cls.getEnclosingType(), S, cls.tsym);
3014 else
3015 return t;
3016 }
3017 // where
3018 public List<Type> freshTypeVariables(List<Type> types) {
3019 ListBuffer<Type> result = lb();
3020 for (Type t : types) {
3021 if (t.tag == WILDCARD) {
3022 Type bound = ((WildcardType)t).getExtendsBound();
3023 if (bound == null)
3024 bound = syms.objectType;
3025 result.append(new CapturedType(capturedName,
3026 syms.noSymbol,
3027 bound,
3028 syms.botType,
3029 (WildcardType)t));
3030 } else {
3031 result.append(t);
3032 }
3033 }
3034 return result.toList();
3035 }
3036 // </editor-fold>
3038 // <editor-fold defaultstate="collapsed" desc="Internal utility methods">
3039 private List<Type> upperBounds(List<Type> ss) {
3040 if (ss.isEmpty()) return ss;
3041 Type head = upperBound(ss.head);
3042 List<Type> tail = upperBounds(ss.tail);
3043 if (head != ss.head || tail != ss.tail)
3044 return tail.prepend(head);
3045 else
3046 return ss;
3047 }
3049 private boolean sideCast(Type from, Type to, Warner warn) {
3050 // We are casting from type $from$ to type $to$, which are
3051 // non-final unrelated types. This method
3052 // tries to reject a cast by transferring type parameters
3053 // from $to$ to $from$ by common superinterfaces.
3054 boolean reverse = false;
3055 Type target = to;
3056 if ((to.tsym.flags() & INTERFACE) == 0) {
3057 assert (from.tsym.flags() & INTERFACE) != 0;
3058 reverse = true;
3059 to = from;
3060 from = target;
3061 }
3062 List<Type> commonSupers = superClosure(to, erasure(from));
3063 boolean giveWarning = commonSupers.isEmpty();
3064 // The arguments to the supers could be unified here to
3065 // get a more accurate analysis
3066 while (commonSupers.nonEmpty()) {
3067 Type t1 = asSuper(from, commonSupers.head.tsym);
3068 Type t2 = commonSupers.head; // same as asSuper(to, commonSupers.head.tsym);
3069 if (disjointTypes(t1.getTypeArguments(), t2.getTypeArguments()))
3070 return false;
3071 giveWarning = giveWarning || (reverse ? giveWarning(t2, t1) : giveWarning(t1, t2));
3072 commonSupers = commonSupers.tail;
3073 }
3074 if (giveWarning && !isReifiable(reverse ? from : to))
3075 warn.warnUnchecked();
3076 if (!source.allowCovariantReturns())
3077 // reject if there is a common method signature with
3078 // incompatible return types.
3079 chk.checkCompatibleAbstracts(warn.pos(), from, to);
3080 return true;
3081 }
3083 private boolean sideCastFinal(Type from, Type to, Warner warn) {
3084 // We are casting from type $from$ to type $to$, which are
3085 // unrelated types one of which is final and the other of
3086 // which is an interface. This method
3087 // tries to reject a cast by transferring type parameters
3088 // from the final class to the interface.
3089 boolean reverse = false;
3090 Type target = to;
3091 if ((to.tsym.flags() & INTERFACE) == 0) {
3092 assert (from.tsym.flags() & INTERFACE) != 0;
3093 reverse = true;
3094 to = from;
3095 from = target;
3096 }
3097 assert (from.tsym.flags() & FINAL) != 0;
3098 Type t1 = asSuper(from, to.tsym);
3099 if (t1 == null) return false;
3100 Type t2 = to;
3101 if (disjointTypes(t1.getTypeArguments(), t2.getTypeArguments()))
3102 return false;
3103 if (!source.allowCovariantReturns())
3104 // reject if there is a common method signature with
3105 // incompatible return types.
3106 chk.checkCompatibleAbstracts(warn.pos(), from, to);
3107 if (!isReifiable(target) &&
3108 (reverse ? giveWarning(t2, t1) : giveWarning(t1, t2)))
3109 warn.warnUnchecked();
3110 return true;
3111 }
3113 private boolean giveWarning(Type from, Type to) {
3114 Type subFrom = asSub(from, to.tsym);
3115 return to.isParameterized() &&
3116 (!(isUnbounded(to) ||
3117 isSubtype(from, to) ||
3118 ((subFrom != null) && isSameType(subFrom, to))));
3119 }
3121 private List<Type> superClosure(Type t, Type s) {
3122 List<Type> cl = List.nil();
3123 for (List<Type> l = interfaces(t); l.nonEmpty(); l = l.tail) {
3124 if (isSubtype(s, erasure(l.head))) {
3125 cl = insert(cl, l.head);
3126 } else {
3127 cl = union(cl, superClosure(l.head, s));
3128 }
3129 }
3130 return cl;
3131 }
3133 private boolean containsTypeEquivalent(Type t, Type s) {
3134 return
3135 isSameType(t, s) || // shortcut
3136 containsType(t, s) && containsType(s, t);
3137 }
3139 // <editor-fold defaultstate="collapsed" desc="adapt">
3140 /**
3141 * Adapt a type by computing a substitution which maps a source
3142 * type to a target type.
3143 *
3144 * @param source the source type
3145 * @param target the target type
3146 * @param from the type variables of the computed substitution
3147 * @param to the types of the computed substitution.
3148 */
3149 public void adapt(Type source,
3150 Type target,
3151 ListBuffer<Type> from,
3152 ListBuffer<Type> to) throws AdaptFailure {
3153 new Adapter(from, to).adapt(source, target);
3154 }
3156 class Adapter extends SimpleVisitor<Void, Type> {
3158 ListBuffer<Type> from;
3159 ListBuffer<Type> to;
3160 Map<Symbol,Type> mapping;
3162 Adapter(ListBuffer<Type> from, ListBuffer<Type> to) {
3163 this.from = from;
3164 this.to = to;
3165 mapping = new HashMap<Symbol,Type>();
3166 }
3168 public void adapt(Type source, Type target) throws AdaptFailure {
3169 visit(source, target);
3170 List<Type> fromList = from.toList();
3171 List<Type> toList = to.toList();
3172 while (!fromList.isEmpty()) {
3173 Type val = mapping.get(fromList.head.tsym);
3174 if (toList.head != val)
3175 toList.head = val;
3176 fromList = fromList.tail;
3177 toList = toList.tail;
3178 }
3179 }
3181 @Override
3182 public Void visitClassType(ClassType source, Type target) throws AdaptFailure {
3183 if (target.tag == CLASS)
3184 adaptRecursive(source.allparams(), target.allparams());
3185 return null;
3186 }
3188 @Override
3189 public Void visitArrayType(ArrayType source, Type target) throws AdaptFailure {
3190 if (target.tag == ARRAY)
3191 adaptRecursive(elemtype(source), elemtype(target));
3192 return null;
3193 }
3195 @Override
3196 public Void visitWildcardType(WildcardType source, Type target) throws AdaptFailure {
3197 if (source.isExtendsBound())
3198 adaptRecursive(upperBound(source), upperBound(target));
3199 else if (source.isSuperBound())
3200 adaptRecursive(lowerBound(source), lowerBound(target));
3201 return null;
3202 }
3204 @Override
3205 public Void visitTypeVar(TypeVar source, Type target) throws AdaptFailure {
3206 // Check to see if there is
3207 // already a mapping for $source$, in which case
3208 // the old mapping will be merged with the new
3209 Type val = mapping.get(source.tsym);
3210 if (val != null) {
3211 if (val.isSuperBound() && target.isSuperBound()) {
3212 val = isSubtype(lowerBound(val), lowerBound(target))
3213 ? target : val;
3214 } else if (val.isExtendsBound() && target.isExtendsBound()) {
3215 val = isSubtype(upperBound(val), upperBound(target))
3216 ? val : target;
3217 } else if (!isSameType(val, target)) {
3218 throw new AdaptFailure();
3219 }
3220 } else {
3221 val = target;
3222 from.append(source);
3223 to.append(target);
3224 }
3225 mapping.put(source.tsym, val);
3226 return null;
3227 }
3229 @Override
3230 public Void visitType(Type source, Type target) {
3231 return null;
3232 }
3234 private Set<TypePair> cache = new HashSet<TypePair>();
3236 private void adaptRecursive(Type source, Type target) {
3237 TypePair pair = new TypePair(source, target);
3238 if (cache.add(pair)) {
3239 try {
3240 visit(source, target);
3241 } finally {
3242 cache.remove(pair);
3243 }
3244 }
3245 }
3247 private void adaptRecursive(List<Type> source, List<Type> target) {
3248 if (source.length() == target.length()) {
3249 while (source.nonEmpty()) {
3250 adaptRecursive(source.head, target.head);
3251 source = source.tail;
3252 target = target.tail;
3253 }
3254 }
3255 }
3256 }
3258 public static class AdaptFailure extends RuntimeException {
3259 static final long serialVersionUID = -7490231548272701566L;
3260 }
3262 private void adaptSelf(Type t,
3263 ListBuffer<Type> from,
3264 ListBuffer<Type> to) {
3265 try {
3266 //if (t.tsym.type != t)
3267 adapt(t.tsym.type, t, from, to);
3268 } catch (AdaptFailure ex) {
3269 // Adapt should never fail calculating a mapping from
3270 // t.tsym.type to t as there can be no merge problem.
3271 throw new AssertionError(ex);
3272 }
3273 }
3274 // </editor-fold>
3276 /**
3277 * Rewrite all type variables (universal quantifiers) in the given
3278 * type to wildcards (existential quantifiers). This is used to
3279 * determine if a cast is allowed. For example, if high is true
3280 * and {@code T <: Number}, then {@code List<T>} is rewritten to
3281 * {@code List<? extends Number>}. Since {@code List<Integer> <:
3282 * List<? extends Number>} a {@code List<T>} can be cast to {@code
3283 * List<Integer>} with a warning.
3284 * @param t a type
3285 * @param high if true return an upper bound; otherwise a lower
3286 * bound
3287 * @param rewriteTypeVars only rewrite captured wildcards if false;
3288 * otherwise rewrite all type variables
3289 * @return the type rewritten with wildcards (existential
3290 * quantifiers) only
3291 */
3292 private Type rewriteQuantifiers(Type t, boolean high, boolean rewriteTypeVars) {
3293 return new Rewriter(high, rewriteTypeVars).visit(t);
3294 }
3296 class Rewriter extends UnaryVisitor<Type> {
3298 boolean high;
3299 boolean rewriteTypeVars;
3301 Rewriter(boolean high, boolean rewriteTypeVars) {
3302 this.high = high;
3303 this.rewriteTypeVars = rewriteTypeVars;
3304 }
3306 @Override
3307 public Type visitClassType(ClassType t, Void s) {
3308 ListBuffer<Type> rewritten = new ListBuffer<Type>();
3309 boolean changed = false;
3310 for (Type arg : t.allparams()) {
3311 Type bound = visit(arg);
3312 if (arg != bound) {
3313 changed = true;
3314 }
3315 rewritten.append(bound);
3316 }
3317 if (changed)
3318 return subst(t.tsym.type,
3319 t.tsym.type.allparams(),
3320 rewritten.toList());
3321 else
3322 return t;
3323 }
3325 public Type visitType(Type t, Void s) {
3326 return high ? upperBound(t) : lowerBound(t);
3327 }
3329 @Override
3330 public Type visitCapturedType(CapturedType t, Void s) {
3331 Type bound = visitWildcardType(t.wildcard, null);
3332 return (bound.contains(t)) ?
3333 (high ? syms.objectType : syms.botType) :
3334 bound;
3335 }
3337 @Override
3338 public Type visitTypeVar(TypeVar t, Void s) {
3339 if (rewriteTypeVars) {
3340 Type bound = high ?
3341 (t.bound.contains(t) ?
3342 syms.objectType :
3343 visit(t.bound)) :
3344 syms.botType;
3345 return rewriteAsWildcardType(bound, t);
3346 }
3347 else
3348 return t;
3349 }
3351 @Override
3352 public Type visitWildcardType(WildcardType t, Void s) {
3353 Type bound = high ? t.getExtendsBound() :
3354 t.getSuperBound();
3355 if (bound == null)
3356 bound = high ? syms.objectType : syms.botType;
3357 return rewriteAsWildcardType(visit(bound), t.bound);
3358 }
3360 private Type rewriteAsWildcardType(Type bound, TypeVar formal) {
3361 return high ?
3362 makeExtendsWildcard(B(bound), formal) :
3363 makeSuperWildcard(B(bound), formal);
3364 }
3366 Type B(Type t) {
3367 while (t.tag == WILDCARD) {
3368 WildcardType w = (WildcardType)t;
3369 t = high ?
3370 w.getExtendsBound() :
3371 w.getSuperBound();
3372 if (t == null) {
3373 t = high ? syms.objectType : syms.botType;
3374 }
3375 }
3376 return t;
3377 }
3378 }
3381 /**
3382 * Create a wildcard with the given upper (extends) bound; create
3383 * an unbounded wildcard if bound is Object.
3384 *
3385 * @param bound the upper bound
3386 * @param formal the formal type parameter that will be
3387 * substituted by the wildcard
3388 */
3389 private WildcardType makeExtendsWildcard(Type bound, TypeVar formal) {
3390 if (bound == syms.objectType) {
3391 return new WildcardType(syms.objectType,
3392 BoundKind.UNBOUND,
3393 syms.boundClass,
3394 formal);
3395 } else {
3396 return new WildcardType(bound,
3397 BoundKind.EXTENDS,
3398 syms.boundClass,
3399 formal);
3400 }
3401 }
3403 /**
3404 * Create a wildcard with the given lower (super) bound; create an
3405 * unbounded wildcard if bound is bottom (type of {@code null}).
3406 *
3407 * @param bound the lower bound
3408 * @param formal the formal type parameter that will be
3409 * substituted by the wildcard
3410 */
3411 private WildcardType makeSuperWildcard(Type bound, TypeVar formal) {
3412 if (bound.tag == BOT) {
3413 return new WildcardType(syms.objectType,
3414 BoundKind.UNBOUND,
3415 syms.boundClass,
3416 formal);
3417 } else {
3418 return new WildcardType(bound,
3419 BoundKind.SUPER,
3420 syms.boundClass,
3421 formal);
3422 }
3423 }
3425 /**
3426 * A wrapper for a type that allows use in sets.
3427 */
3428 class SingletonType {
3429 final Type t;
3430 SingletonType(Type t) {
3431 this.t = t;
3432 }
3433 public int hashCode() {
3434 return Types.hashCode(t);
3435 }
3436 public boolean equals(Object obj) {
3437 return (obj instanceof SingletonType) &&
3438 isSameType(t, ((SingletonType)obj).t);
3439 }
3440 public String toString() {
3441 return t.toString();
3442 }
3443 }
3444 // </editor-fold>
3446 // <editor-fold defaultstate="collapsed" desc="Visitors">
3447 /**
3448 * A default visitor for types. All visitor methods except
3449 * visitType are implemented by delegating to visitType. Concrete
3450 * subclasses must provide an implementation of visitType and can
3451 * override other methods as needed.
3452 *
3453 * @param <R> the return type of the operation implemented by this
3454 * visitor; use Void if no return type is needed.
3455 * @param <S> the type of the second argument (the first being the
3456 * type itself) of the operation implemented by this visitor; use
3457 * Void if a second argument is not needed.
3458 */
3459 public static abstract class DefaultTypeVisitor<R,S> implements Type.Visitor<R,S> {
3460 final public R visit(Type t, S s) { return t.accept(this, s); }
3461 public R visitClassType(ClassType t, S s) { return visitType(t, s); }
3462 public R visitWildcardType(WildcardType t, S s) { return visitType(t, s); }
3463 public R visitArrayType(ArrayType t, S s) { return visitType(t, s); }
3464 public R visitMethodType(MethodType t, S s) { return visitType(t, s); }
3465 public R visitPackageType(PackageType t, S s) { return visitType(t, s); }
3466 public R visitTypeVar(TypeVar t, S s) { return visitType(t, s); }
3467 public R visitCapturedType(CapturedType t, S s) { return visitType(t, s); }
3468 public R visitForAll(ForAll t, S s) { return visitType(t, s); }
3469 public R visitUndetVar(UndetVar t, S s) { return visitType(t, s); }
3470 public R visitErrorType(ErrorType t, S s) { return visitType(t, s); }
3471 }
3473 /**
3474 * A default visitor for symbols. All visitor methods except
3475 * visitSymbol are implemented by delegating to visitSymbol. Concrete
3476 * subclasses must provide an implementation of visitSymbol and can
3477 * override other methods as needed.
3478 *
3479 * @param <R> the return type of the operation implemented by this
3480 * visitor; use Void if no return type is needed.
3481 * @param <S> the type of the second argument (the first being the
3482 * symbol itself) of the operation implemented by this visitor; use
3483 * Void if a second argument is not needed.
3484 */
3485 public static abstract class DefaultSymbolVisitor<R,S> implements Symbol.Visitor<R,S> {
3486 final public R visit(Symbol s, S arg) { return s.accept(this, arg); }
3487 public R visitClassSymbol(ClassSymbol s, S arg) { return visitSymbol(s, arg); }
3488 public R visitMethodSymbol(MethodSymbol s, S arg) { return visitSymbol(s, arg); }
3489 public R visitOperatorSymbol(OperatorSymbol s, S arg) { return visitSymbol(s, arg); }
3490 public R visitPackageSymbol(PackageSymbol s, S arg) { return visitSymbol(s, arg); }
3491 public R visitTypeSymbol(TypeSymbol s, S arg) { return visitSymbol(s, arg); }
3492 public R visitVarSymbol(VarSymbol s, S arg) { return visitSymbol(s, arg); }
3493 }
3495 /**
3496 * A <em>simple</em> visitor for types. This visitor is simple as
3497 * captured wildcards, for-all types (generic methods), and
3498 * undetermined type variables (part of inference) are hidden.
3499 * Captured wildcards are hidden by treating them as type
3500 * variables and the rest are hidden by visiting their qtypes.
3501 *
3502 * @param <R> the return type of the operation implemented by this
3503 * visitor; use Void if no return type is needed.
3504 * @param <S> the type of the second argument (the first being the
3505 * type itself) of the operation implemented by this visitor; use
3506 * Void if a second argument is not needed.
3507 */
3508 public static abstract class SimpleVisitor<R,S> extends DefaultTypeVisitor<R,S> {
3509 @Override
3510 public R visitCapturedType(CapturedType t, S s) {
3511 return visitTypeVar(t, s);
3512 }
3513 @Override
3514 public R visitForAll(ForAll t, S s) {
3515 return visit(t.qtype, s);
3516 }
3517 @Override
3518 public R visitUndetVar(UndetVar t, S s) {
3519 return visit(t.qtype, s);
3520 }
3521 }
3523 /**
3524 * A plain relation on types. That is a 2-ary function on the
3525 * form Type × Type → Boolean.
3526 * <!-- In plain text: Type x Type -> Boolean -->
3527 */
3528 public static abstract class TypeRelation extends SimpleVisitor<Boolean,Type> {}
3530 /**
3531 * A convenience visitor for implementing operations that only
3532 * require one argument (the type itself), that is, unary
3533 * operations.
3534 *
3535 * @param <R> the return type of the operation implemented by this
3536 * visitor; use Void if no return type is needed.
3537 */
3538 public static abstract class UnaryVisitor<R> extends SimpleVisitor<R,Void> {
3539 final public R visit(Type t) { return t.accept(this, null); }
3540 }
3542 /**
3543 * A visitor for implementing a mapping from types to types. The
3544 * default behavior of this class is to implement the identity
3545 * mapping (mapping a type to itself). This can be overridden in
3546 * subclasses.
3547 *
3548 * @param <S> the type of the second argument (the first being the
3549 * type itself) of this mapping; use Void if a second argument is
3550 * not needed.
3551 */
3552 public static class MapVisitor<S> extends DefaultTypeVisitor<Type,S> {
3553 final public Type visit(Type t) { return t.accept(this, null); }
3554 public Type visitType(Type t, S s) { return t; }
3555 }
3556 // </editor-fold>
3557 }
