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src/share/classes/com/sun/tools/javac/comp/Resolve.java@03c26c60499c
src/share/classes/com/sun/tools/javac/comp/Resolve.java
Sat, 14 Sep 2013 15:23:21 +0100
- author
- vromero
- date
- Sat, 14 Sep 2013 15:23:21 +0100
- changeset 2026
- 03c26c60499c
- parent 2003
- 9be0afbdf244
- child 2047
- 5f915a0c9615
- permissions
- -rw-r--r--
8024207: javac crash in Flow.AssignAnalyzer.visitIdent
Reviewed-by: jjg
1 /*
2 * Copyright (c) 1999, 2013, 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.comp;
28 import com.sun.tools.javac.api.Formattable.LocalizedString;
29 import com.sun.tools.javac.code.*;
30 import com.sun.tools.javac.code.Symbol.*;
31 import com.sun.tools.javac.code.Type.*;
32 import com.sun.tools.javac.comp.Attr.ResultInfo;
33 import com.sun.tools.javac.comp.Check.CheckContext;
34 import com.sun.tools.javac.comp.DeferredAttr.AttrMode;
35 import com.sun.tools.javac.comp.DeferredAttr.DeferredAttrContext;
36 import com.sun.tools.javac.comp.DeferredAttr.DeferredType;
37 import com.sun.tools.javac.comp.Infer.InferenceContext;
38 import com.sun.tools.javac.comp.Infer.FreeTypeListener;
39 import com.sun.tools.javac.comp.Resolve.MethodResolutionContext.Candidate;
40 import com.sun.tools.javac.comp.Resolve.MethodResolutionDiagHelper.DiagnosticRewriter;
41 import com.sun.tools.javac.comp.Resolve.MethodResolutionDiagHelper.Template;
42 import com.sun.tools.javac.jvm.*;
43 import com.sun.tools.javac.main.Option;
44 import com.sun.tools.javac.tree.*;
45 import com.sun.tools.javac.tree.JCTree.*;
46 import com.sun.tools.javac.tree.JCTree.JCMemberReference.ReferenceKind;
47 import com.sun.tools.javac.tree.JCTree.JCPolyExpression.*;
48 import com.sun.tools.javac.util.*;
49 import com.sun.tools.javac.util.JCDiagnostic.DiagnosticFlag;
50 import com.sun.tools.javac.util.JCDiagnostic.DiagnosticPosition;
51 import com.sun.tools.javac.util.JCDiagnostic.DiagnosticType;
53 import java.util.Arrays;
54 import java.util.Collection;
55 import java.util.EnumMap;
56 import java.util.EnumSet;
57 import java.util.Iterator;
58 import java.util.LinkedHashMap;
59 import java.util.LinkedHashSet;
60 import java.util.Map;
62 import javax.lang.model.element.ElementVisitor;
64 import static com.sun.tools.javac.code.Flags.*;
65 import static com.sun.tools.javac.code.Flags.BLOCK;
66 import static com.sun.tools.javac.code.Kinds.*;
67 import static com.sun.tools.javac.code.Kinds.ERRONEOUS;
68 import static com.sun.tools.javac.code.TypeTag.*;
69 import static com.sun.tools.javac.comp.Resolve.MethodResolutionPhase.*;
70 import static com.sun.tools.javac.tree.JCTree.Tag.*;
72 /** Helper class for name resolution, used mostly by the attribution phase.
73 *
74 * <p><b>This is NOT part of any supported API.
75 * If you write code that depends on this, you do so at your own risk.
76 * This code and its internal interfaces are subject to change or
77 * deletion without notice.</b>
78 */
79 public class Resolve {
80 protected static final Context.Key<Resolve> resolveKey =
81 new Context.Key<Resolve>();
83 Names names;
84 Log log;
85 Symtab syms;
86 Attr attr;
87 DeferredAttr deferredAttr;
88 Check chk;
89 Infer infer;
90 ClassReader reader;
91 TreeInfo treeinfo;
92 Types types;
93 JCDiagnostic.Factory diags;
94 public final boolean boxingEnabled; // = source.allowBoxing();
95 public final boolean varargsEnabled; // = source.allowVarargs();
96 public final boolean allowMethodHandles;
97 public final boolean allowDefaultMethods;
98 public final boolean allowStructuralMostSpecific;
99 private final boolean debugResolve;
100 private final boolean compactMethodDiags;
101 final EnumSet<VerboseResolutionMode> verboseResolutionMode;
103 Scope polymorphicSignatureScope;
105 protected Resolve(Context context) {
106 context.put(resolveKey, this);
107 syms = Symtab.instance(context);
109 varNotFound = new
110 SymbolNotFoundError(ABSENT_VAR);
111 methodNotFound = new
112 SymbolNotFoundError(ABSENT_MTH);
113 typeNotFound = new
114 SymbolNotFoundError(ABSENT_TYP);
116 names = Names.instance(context);
117 log = Log.instance(context);
118 attr = Attr.instance(context);
119 deferredAttr = DeferredAttr.instance(context);
120 chk = Check.instance(context);
121 infer = Infer.instance(context);
122 reader = ClassReader.instance(context);
123 treeinfo = TreeInfo.instance(context);
124 types = Types.instance(context);
125 diags = JCDiagnostic.Factory.instance(context);
126 Source source = Source.instance(context);
127 boxingEnabled = source.allowBoxing();
128 varargsEnabled = source.allowVarargs();
129 Options options = Options.instance(context);
130 debugResolve = options.isSet("debugresolve");
131 compactMethodDiags = options.isSet(Option.XDIAGS, "compact") ||
132 options.isUnset(Option.XDIAGS) && options.isUnset("rawDiagnostics");
133 verboseResolutionMode = VerboseResolutionMode.getVerboseResolutionMode(options);
134 Target target = Target.instance(context);
135 allowMethodHandles = target.hasMethodHandles();
136 allowDefaultMethods = source.allowDefaultMethods();
137 allowStructuralMostSpecific = source.allowStructuralMostSpecific();
138 polymorphicSignatureScope = new Scope(syms.noSymbol);
140 inapplicableMethodException = new InapplicableMethodException(diags);
141 }
143 /** error symbols, which are returned when resolution fails
144 */
145 private final SymbolNotFoundError varNotFound;
146 private final SymbolNotFoundError methodNotFound;
147 private final SymbolNotFoundError typeNotFound;
149 public static Resolve instance(Context context) {
150 Resolve instance = context.get(resolveKey);
151 if (instance == null)
152 instance = new Resolve(context);
153 return instance;
154 }
156 // <editor-fold defaultstate="collapsed" desc="Verbose resolution diagnostics support">
157 enum VerboseResolutionMode {
158 SUCCESS("success"),
159 FAILURE("failure"),
160 APPLICABLE("applicable"),
161 INAPPLICABLE("inapplicable"),
162 DEFERRED_INST("deferred-inference"),
163 PREDEF("predef"),
164 OBJECT_INIT("object-init"),
165 INTERNAL("internal");
167 final String opt;
169 private VerboseResolutionMode(String opt) {
170 this.opt = opt;
171 }
173 static EnumSet<VerboseResolutionMode> getVerboseResolutionMode(Options opts) {
174 String s = opts.get("verboseResolution");
175 EnumSet<VerboseResolutionMode> res = EnumSet.noneOf(VerboseResolutionMode.class);
176 if (s == null) return res;
177 if (s.contains("all")) {
178 res = EnumSet.allOf(VerboseResolutionMode.class);
179 }
180 Collection<String> args = Arrays.asList(s.split(","));
181 for (VerboseResolutionMode mode : values()) {
182 if (args.contains(mode.opt)) {
183 res.add(mode);
184 } else if (args.contains("-" + mode.opt)) {
185 res.remove(mode);
186 }
187 }
188 return res;
189 }
190 }
192 void reportVerboseResolutionDiagnostic(DiagnosticPosition dpos, Name name, Type site,
193 List<Type> argtypes, List<Type> typeargtypes, Symbol bestSoFar) {
194 boolean success = bestSoFar.kind < ERRONEOUS;
196 if (success && !verboseResolutionMode.contains(VerboseResolutionMode.SUCCESS)) {
197 return;
198 } else if (!success && !verboseResolutionMode.contains(VerboseResolutionMode.FAILURE)) {
199 return;
200 }
202 if (bestSoFar.name == names.init &&
203 bestSoFar.owner == syms.objectType.tsym &&
204 !verboseResolutionMode.contains(VerboseResolutionMode.OBJECT_INIT)) {
205 return; //skip diags for Object constructor resolution
206 } else if (site == syms.predefClass.type &&
207 !verboseResolutionMode.contains(VerboseResolutionMode.PREDEF)) {
208 return; //skip spurious diags for predef symbols (i.e. operators)
209 } else if (currentResolutionContext.internalResolution &&
210 !verboseResolutionMode.contains(VerboseResolutionMode.INTERNAL)) {
211 return;
212 }
214 int pos = 0;
215 int mostSpecificPos = -1;
216 ListBuffer<JCDiagnostic> subDiags = ListBuffer.lb();
217 for (Candidate c : currentResolutionContext.candidates) {
218 if (currentResolutionContext.step != c.step ||
219 (c.isApplicable() && !verboseResolutionMode.contains(VerboseResolutionMode.APPLICABLE)) ||
220 (!c.isApplicable() && !verboseResolutionMode.contains(VerboseResolutionMode.INAPPLICABLE))) {
221 continue;
222 } else {
223 subDiags.append(c.isApplicable() ?
224 getVerboseApplicableCandidateDiag(pos, c.sym, c.mtype) :
225 getVerboseInapplicableCandidateDiag(pos, c.sym, c.details));
226 if (c.sym == bestSoFar)
227 mostSpecificPos = pos;
228 pos++;
229 }
230 }
231 String key = success ? "verbose.resolve.multi" : "verbose.resolve.multi.1";
232 List<Type> argtypes2 = Type.map(argtypes,
233 deferredAttr.new RecoveryDeferredTypeMap(AttrMode.SPECULATIVE, bestSoFar, currentResolutionContext.step));
234 JCDiagnostic main = diags.note(log.currentSource(), dpos, key, name,
235 site.tsym, mostSpecificPos, currentResolutionContext.step,
236 methodArguments(argtypes2),
237 methodArguments(typeargtypes));
238 JCDiagnostic d = new JCDiagnostic.MultilineDiagnostic(main, subDiags.toList());
239 log.report(d);
240 }
242 JCDiagnostic getVerboseApplicableCandidateDiag(int pos, Symbol sym, Type inst) {
243 JCDiagnostic subDiag = null;
244 if (sym.type.hasTag(FORALL)) {
245 subDiag = diags.fragment("partial.inst.sig", inst);
246 }
248 String key = subDiag == null ?
249 "applicable.method.found" :
250 "applicable.method.found.1";
252 return diags.fragment(key, pos, sym, subDiag);
253 }
255 JCDiagnostic getVerboseInapplicableCandidateDiag(int pos, Symbol sym, JCDiagnostic subDiag) {
256 return diags.fragment("not.applicable.method.found", pos, sym, subDiag);
257 }
258 // </editor-fold>
260 /* ************************************************************************
261 * Identifier resolution
262 *************************************************************************/
264 /** An environment is "static" if its static level is greater than
265 * the one of its outer environment
266 */
267 protected static boolean isStatic(Env<AttrContext> env) {
268 return env.info.staticLevel > env.outer.info.staticLevel;
269 }
271 /** An environment is an "initializer" if it is a constructor or
272 * an instance initializer.
273 */
274 static boolean isInitializer(Env<AttrContext> env) {
275 Symbol owner = env.info.scope.owner;
276 return owner.isConstructor() ||
277 owner.owner.kind == TYP &&
278 (owner.kind == VAR ||
279 owner.kind == MTH && (owner.flags() & BLOCK) != 0) &&
280 (owner.flags() & STATIC) == 0;
281 }
283 /** Is class accessible in given evironment?
284 * @param env The current environment.
285 * @param c The class whose accessibility is checked.
286 */
287 public boolean isAccessible(Env<AttrContext> env, TypeSymbol c) {
288 return isAccessible(env, c, false);
289 }
291 public boolean isAccessible(Env<AttrContext> env, TypeSymbol c, boolean checkInner) {
292 boolean isAccessible = false;
293 switch ((short)(c.flags() & AccessFlags)) {
294 case PRIVATE:
295 isAccessible =
296 env.enclClass.sym.outermostClass() ==
297 c.owner.outermostClass();
298 break;
299 case 0:
300 isAccessible =
301 env.toplevel.packge == c.owner // fast special case
302 ||
303 env.toplevel.packge == c.packge()
304 ||
305 // Hack: this case is added since synthesized default constructors
306 // of anonymous classes should be allowed to access
307 // classes which would be inaccessible otherwise.
308 env.enclMethod != null &&
309 (env.enclMethod.mods.flags & ANONCONSTR) != 0;
310 break;
311 default: // error recovery
312 case PUBLIC:
313 isAccessible = true;
314 break;
315 case PROTECTED:
316 isAccessible =
317 env.toplevel.packge == c.owner // fast special case
318 ||
319 env.toplevel.packge == c.packge()
320 ||
321 isInnerSubClass(env.enclClass.sym, c.owner);
322 break;
323 }
324 return (checkInner == false || c.type.getEnclosingType() == Type.noType) ?
325 isAccessible :
326 isAccessible && isAccessible(env, c.type.getEnclosingType(), checkInner);
327 }
328 //where
329 /** Is given class a subclass of given base class, or an inner class
330 * of a subclass?
331 * Return null if no such class exists.
332 * @param c The class which is the subclass or is contained in it.
333 * @param base The base class
334 */
335 private boolean isInnerSubClass(ClassSymbol c, Symbol base) {
336 while (c != null && !c.isSubClass(base, types)) {
337 c = c.owner.enclClass();
338 }
339 return c != null;
340 }
342 boolean isAccessible(Env<AttrContext> env, Type t) {
343 return isAccessible(env, t, false);
344 }
346 boolean isAccessible(Env<AttrContext> env, Type t, boolean checkInner) {
347 return (t.hasTag(ARRAY))
348 ? isAccessible(env, types.upperBound(types.elemtype(t)))
349 : isAccessible(env, t.tsym, checkInner);
350 }
352 /** Is symbol accessible as a member of given type in given environment?
353 * @param env The current environment.
354 * @param site The type of which the tested symbol is regarded
355 * as a member.
356 * @param sym The symbol.
357 */
358 public boolean isAccessible(Env<AttrContext> env, Type site, Symbol sym) {
359 return isAccessible(env, site, sym, false);
360 }
361 public boolean isAccessible(Env<AttrContext> env, Type site, Symbol sym, boolean checkInner) {
362 if (sym.name == names.init && sym.owner != site.tsym) return false;
363 switch ((short)(sym.flags() & AccessFlags)) {
364 case PRIVATE:
365 return
366 (env.enclClass.sym == sym.owner // fast special case
367 ||
368 env.enclClass.sym.outermostClass() ==
369 sym.owner.outermostClass())
370 &&
371 sym.isInheritedIn(site.tsym, types);
372 case 0:
373 return
374 (env.toplevel.packge == sym.owner.owner // fast special case
375 ||
376 env.toplevel.packge == sym.packge())
377 &&
378 isAccessible(env, site, checkInner)
379 &&
380 sym.isInheritedIn(site.tsym, types)
381 &&
382 notOverriddenIn(site, sym);
383 case PROTECTED:
384 return
385 (env.toplevel.packge == sym.owner.owner // fast special case
386 ||
387 env.toplevel.packge == sym.packge()
388 ||
389 isProtectedAccessible(sym, env.enclClass.sym, site)
390 ||
391 // OK to select instance method or field from 'super' or type name
392 // (but type names should be disallowed elsewhere!)
393 env.info.selectSuper && (sym.flags() & STATIC) == 0 && sym.kind != TYP)
394 &&
395 isAccessible(env, site, checkInner)
396 &&
397 notOverriddenIn(site, sym);
398 default: // this case includes erroneous combinations as well
399 return isAccessible(env, site, checkInner) && notOverriddenIn(site, sym);
400 }
401 }
402 //where
403 /* `sym' is accessible only if not overridden by
404 * another symbol which is a member of `site'
405 * (because, if it is overridden, `sym' is not strictly
406 * speaking a member of `site'). A polymorphic signature method
407 * cannot be overridden (e.g. MH.invokeExact(Object[])).
408 */
409 private boolean notOverriddenIn(Type site, Symbol sym) {
410 if (sym.kind != MTH || sym.isConstructor() || sym.isStatic())
411 return true;
412 else {
413 Symbol s2 = ((MethodSymbol)sym).implementation(site.tsym, types, true);
414 return (s2 == null || s2 == sym || sym.owner == s2.owner ||
415 !types.isSubSignature(types.memberType(site, s2), types.memberType(site, sym)));
416 }
417 }
418 //where
419 /** Is given protected symbol accessible if it is selected from given site
420 * and the selection takes place in given class?
421 * @param sym The symbol with protected access
422 * @param c The class where the access takes place
423 * @site The type of the qualifier
424 */
425 private
426 boolean isProtectedAccessible(Symbol sym, ClassSymbol c, Type site) {
427 while (c != null &&
428 !(c.isSubClass(sym.owner, types) &&
429 (c.flags() & INTERFACE) == 0 &&
430 // In JLS 2e 6.6.2.1, the subclass restriction applies
431 // only to instance fields and methods -- types are excluded
432 // regardless of whether they are declared 'static' or not.
433 ((sym.flags() & STATIC) != 0 || sym.kind == TYP || site.tsym.isSubClass(c, types))))
434 c = c.owner.enclClass();
435 return c != null;
436 }
438 /**
439 * Performs a recursive scan of a type looking for accessibility problems
440 * from current attribution environment
441 */
442 void checkAccessibleType(Env<AttrContext> env, Type t) {
443 accessibilityChecker.visit(t, env);
444 }
446 /**
447 * Accessibility type-visitor
448 */
449 Types.SimpleVisitor<Void, Env<AttrContext>> accessibilityChecker =
450 new Types.SimpleVisitor<Void, Env<AttrContext>>() {
452 void visit(List<Type> ts, Env<AttrContext> env) {
453 for (Type t : ts) {
454 visit(t, env);
455 }
456 }
458 public Void visitType(Type t, Env<AttrContext> env) {
459 return null;
460 }
462 @Override
463 public Void visitArrayType(ArrayType t, Env<AttrContext> env) {
464 visit(t.elemtype, env);
465 return null;
466 }
468 @Override
469 public Void visitClassType(ClassType t, Env<AttrContext> env) {
470 visit(t.getTypeArguments(), env);
471 if (!isAccessible(env, t, true)) {
472 accessBase(new AccessError(t.tsym), env.tree.pos(), env.enclClass.sym, t, t.tsym.name, true);
473 }
474 return null;
475 }
477 @Override
478 public Void visitWildcardType(WildcardType t, Env<AttrContext> env) {
479 visit(t.type, env);
480 return null;
481 }
483 @Override
484 public Void visitMethodType(MethodType t, Env<AttrContext> env) {
485 visit(t.getParameterTypes(), env);
486 visit(t.getReturnType(), env);
487 visit(t.getThrownTypes(), env);
488 return null;
489 }
490 };
492 /** Try to instantiate the type of a method so that it fits
493 * given type arguments and argument types. If successful, return
494 * the method's instantiated type, else return null.
495 * The instantiation will take into account an additional leading
496 * formal parameter if the method is an instance method seen as a member
497 * of an under determined site. In this case, we treat site as an additional
498 * parameter and the parameters of the class containing the method as
499 * additional type variables that get instantiated.
500 *
501 * @param env The current environment
502 * @param site The type of which the method is a member.
503 * @param m The method symbol.
504 * @param argtypes The invocation's given value arguments.
505 * @param typeargtypes The invocation's given type arguments.
506 * @param allowBoxing Allow boxing conversions of arguments.
507 * @param useVarargs Box trailing arguments into an array for varargs.
508 */
509 Type rawInstantiate(Env<AttrContext> env,
510 Type site,
511 Symbol m,
512 ResultInfo resultInfo,
513 List<Type> argtypes,
514 List<Type> typeargtypes,
515 boolean allowBoxing,
516 boolean useVarargs,
517 Warner warn) throws Infer.InferenceException {
519 Type mt = types.memberType(site, m);
520 // tvars is the list of formal type variables for which type arguments
521 // need to inferred.
522 List<Type> tvars = List.nil();
523 if (typeargtypes == null) typeargtypes = List.nil();
524 if (!mt.hasTag(FORALL) && typeargtypes.nonEmpty()) {
525 // This is not a polymorphic method, but typeargs are supplied
526 // which is fine, see JLS 15.12.2.1
527 } else if (mt.hasTag(FORALL) && typeargtypes.nonEmpty()) {
528 ForAll pmt = (ForAll) mt;
529 if (typeargtypes.length() != pmt.tvars.length())
530 throw inapplicableMethodException.setMessage("arg.length.mismatch"); // not enough args
531 // Check type arguments are within bounds
532 List<Type> formals = pmt.tvars;
533 List<Type> actuals = typeargtypes;
534 while (formals.nonEmpty() && actuals.nonEmpty()) {
535 List<Type> bounds = types.subst(types.getBounds((TypeVar)formals.head),
536 pmt.tvars, typeargtypes);
537 for (; bounds.nonEmpty(); bounds = bounds.tail)
538 if (!types.isSubtypeUnchecked(actuals.head, bounds.head, warn))
539 throw inapplicableMethodException.setMessage("explicit.param.do.not.conform.to.bounds",actuals.head, bounds);
540 formals = formals.tail;
541 actuals = actuals.tail;
542 }
543 mt = types.subst(pmt.qtype, pmt.tvars, typeargtypes);
544 } else if (mt.hasTag(FORALL)) {
545 ForAll pmt = (ForAll) mt;
546 List<Type> tvars1 = types.newInstances(pmt.tvars);
547 tvars = tvars.appendList(tvars1);
548 mt = types.subst(pmt.qtype, pmt.tvars, tvars1);
549 }
551 // find out whether we need to go the slow route via infer
552 boolean instNeeded = tvars.tail != null; /*inlined: tvars.nonEmpty()*/
553 for (List<Type> l = argtypes;
554 l.tail != null/*inlined: l.nonEmpty()*/ && !instNeeded;
555 l = l.tail) {
556 if (l.head.hasTag(FORALL)) instNeeded = true;
557 }
559 if (instNeeded)
560 return infer.instantiateMethod(env,
561 tvars,
562 (MethodType)mt,
563 resultInfo,
564 m,
565 argtypes,
566 allowBoxing,
567 useVarargs,
568 currentResolutionContext,
569 warn);
571 DeferredAttr.DeferredAttrContext dc = currentResolutionContext.deferredAttrContext(m, infer.emptyContext, resultInfo, warn);
572 currentResolutionContext.methodCheck.argumentsAcceptable(env, dc,
573 argtypes, mt.getParameterTypes(), warn);
574 dc.complete();
575 return mt;
576 }
578 Type checkMethod(Env<AttrContext> env,
579 Type site,
580 Symbol m,
581 ResultInfo resultInfo,
582 List<Type> argtypes,
583 List<Type> typeargtypes,
584 Warner warn) {
585 MethodResolutionContext prevContext = currentResolutionContext;
586 try {
587 currentResolutionContext = new MethodResolutionContext();
588 currentResolutionContext.attrMode = DeferredAttr.AttrMode.CHECK;
589 if (env.tree.hasTag(JCTree.Tag.REFERENCE)) {
590 //method/constructor references need special check class
591 //to handle inference variables in 'argtypes' (might happen
592 //during an unsticking round)
593 currentResolutionContext.methodCheck =
594 new MethodReferenceCheck(resultInfo.checkContext.inferenceContext());
595 }
596 MethodResolutionPhase step = currentResolutionContext.step = env.info.pendingResolutionPhase;
597 return rawInstantiate(env, site, m, resultInfo, argtypes, typeargtypes,
598 step.isBoxingRequired(), step.isVarargsRequired(), warn);
599 }
600 finally {
601 currentResolutionContext = prevContext;
602 }
603 }
605 /** Same but returns null instead throwing a NoInstanceException
606 */
607 Type instantiate(Env<AttrContext> env,
608 Type site,
609 Symbol m,
610 ResultInfo resultInfo,
611 List<Type> argtypes,
612 List<Type> typeargtypes,
613 boolean allowBoxing,
614 boolean useVarargs,
615 Warner warn) {
616 try {
617 return rawInstantiate(env, site, m, resultInfo, argtypes, typeargtypes,
618 allowBoxing, useVarargs, warn);
619 } catch (InapplicableMethodException ex) {
620 return null;
621 }
622 }
624 /**
625 * This interface defines an entry point that should be used to perform a
626 * method check. A method check usually consist in determining as to whether
627 * a set of types (actuals) is compatible with another set of types (formals).
628 * Since the notion of compatibility can vary depending on the circumstances,
629 * this interfaces allows to easily add new pluggable method check routines.
630 */
631 interface MethodCheck {
632 /**
633 * Main method check routine. A method check usually consist in determining
634 * as to whether a set of types (actuals) is compatible with another set of
635 * types (formals). If an incompatibility is found, an unchecked exception
636 * is assumed to be thrown.
637 */
638 void argumentsAcceptable(Env<AttrContext> env,
639 DeferredAttrContext deferredAttrContext,
640 List<Type> argtypes,
641 List<Type> formals,
642 Warner warn);
644 /**
645 * Retrieve the method check object that will be used during a
646 * most specific check.
647 */
648 MethodCheck mostSpecificCheck(List<Type> actuals, boolean strict);
649 }
651 /**
652 * Helper enum defining all method check diagnostics (used by resolveMethodCheck).
653 */
654 enum MethodCheckDiag {
655 /**
656 * Actuals and formals differs in length.
657 */
658 ARITY_MISMATCH("arg.length.mismatch", "infer.arg.length.mismatch"),
659 /**
660 * An actual is incompatible with a formal.
661 */
662 ARG_MISMATCH("no.conforming.assignment.exists", "infer.no.conforming.assignment.exists"),
663 /**
664 * An actual is incompatible with the varargs element type.
665 */
666 VARARG_MISMATCH("varargs.argument.mismatch", "infer.varargs.argument.mismatch"),
667 /**
668 * The varargs element type is inaccessible.
669 */
670 INACCESSIBLE_VARARGS("inaccessible.varargs.type", "inaccessible.varargs.type");
672 final String basicKey;
673 final String inferKey;
675 MethodCheckDiag(String basicKey, String inferKey) {
676 this.basicKey = basicKey;
677 this.inferKey = inferKey;
678 }
680 String regex() {
681 return String.format("([a-z]*\\.)*(%s|%s)", basicKey, inferKey);
682 }
683 }
685 /**
686 * Dummy method check object. All methods are deemed applicable, regardless
687 * of their formal parameter types.
688 */
689 MethodCheck nilMethodCheck = new MethodCheck() {
690 public void argumentsAcceptable(Env<AttrContext> env, DeferredAttrContext deferredAttrContext, List<Type> argtypes, List<Type> formals, Warner warn) {
691 //do nothing - method always applicable regardless of actuals
692 }
694 public MethodCheck mostSpecificCheck(List<Type> actuals, boolean strict) {
695 return this;
696 }
697 };
699 /**
700 * Base class for 'real' method checks. The class defines the logic for
701 * iterating through formals and actuals and provides and entry point
702 * that can be used by subclasses in order to define the actual check logic.
703 */
704 abstract class AbstractMethodCheck implements MethodCheck {
705 @Override
706 public void argumentsAcceptable(final Env<AttrContext> env,
707 DeferredAttrContext deferredAttrContext,
708 List<Type> argtypes,
709 List<Type> formals,
710 Warner warn) {
711 //should we expand formals?
712 boolean useVarargs = deferredAttrContext.phase.isVarargsRequired();
713 List<JCExpression> trees = TreeInfo.args(env.tree);
715 //inference context used during this method check
716 InferenceContext inferenceContext = deferredAttrContext.inferenceContext;
718 Type varargsFormal = useVarargs ? formals.last() : null;
720 if (varargsFormal == null &&
721 argtypes.size() != formals.size()) {
722 reportMC(env.tree, MethodCheckDiag.ARITY_MISMATCH, inferenceContext); // not enough args
723 }
725 while (argtypes.nonEmpty() && formals.head != varargsFormal) {
726 DiagnosticPosition pos = trees != null ? trees.head : null;
727 checkArg(pos, false, argtypes.head, formals.head, deferredAttrContext, warn);
728 argtypes = argtypes.tail;
729 formals = formals.tail;
730 trees = trees != null ? trees.tail : trees;
731 }
733 if (formals.head != varargsFormal) {
734 reportMC(env.tree, MethodCheckDiag.ARITY_MISMATCH, inferenceContext); // not enough args
735 }
737 if (useVarargs) {
738 //note: if applicability check is triggered by most specific test,
739 //the last argument of a varargs is _not_ an array type (see JLS 15.12.2.5)
740 final Type elt = types.elemtype(varargsFormal);
741 while (argtypes.nonEmpty()) {
742 DiagnosticPosition pos = trees != null ? trees.head : null;
743 checkArg(pos, true, argtypes.head, elt, deferredAttrContext, warn);
744 argtypes = argtypes.tail;
745 trees = trees != null ? trees.tail : trees;
746 }
747 }
748 }
750 /**
751 * Does the actual argument conforms to the corresponding formal?
752 */
753 abstract void checkArg(DiagnosticPosition pos, boolean varargs, Type actual, Type formal, DeferredAttrContext deferredAttrContext, Warner warn);
755 protected void reportMC(DiagnosticPosition pos, MethodCheckDiag diag, InferenceContext inferenceContext, Object... args) {
756 boolean inferDiag = inferenceContext != infer.emptyContext;
757 InapplicableMethodException ex = inferDiag ?
758 infer.inferenceException : inapplicableMethodException;
759 if (inferDiag && (!diag.inferKey.equals(diag.basicKey))) {
760 Object[] args2 = new Object[args.length + 1];
761 System.arraycopy(args, 0, args2, 1, args.length);
762 args2[0] = inferenceContext.inferenceVars();
763 args = args2;
764 }
765 String key = inferDiag ? diag.inferKey : diag.basicKey;
766 throw ex.setMessage(diags.create(DiagnosticType.FRAGMENT, log.currentSource(), pos, key, args));
767 }
769 public MethodCheck mostSpecificCheck(List<Type> actuals, boolean strict) {
770 return nilMethodCheck;
771 }
772 }
774 /**
775 * Arity-based method check. A method is applicable if the number of actuals
776 * supplied conforms to the method signature.
777 */
778 MethodCheck arityMethodCheck = new AbstractMethodCheck() {
779 @Override
780 void checkArg(DiagnosticPosition pos, boolean varargs, Type actual, Type formal, DeferredAttrContext deferredAttrContext, Warner warn) {
781 //do nothing - actual always compatible to formals
782 }
783 };
785 List<Type> dummyArgs(int length) {
786 ListBuffer<Type> buf = ListBuffer.lb();
787 for (int i = 0 ; i < length ; i++) {
788 buf.append(Type.noType);
789 }
790 return buf.toList();
791 }
793 /**
794 * Main method applicability routine. Given a list of actual types A,
795 * a list of formal types F, determines whether the types in A are
796 * compatible (by method invocation conversion) with the types in F.
797 *
798 * Since this routine is shared between overload resolution and method
799 * type-inference, a (possibly empty) inference context is used to convert
800 * formal types to the corresponding 'undet' form ahead of a compatibility
801 * check so that constraints can be propagated and collected.
802 *
803 * Moreover, if one or more types in A is a deferred type, this routine uses
804 * DeferredAttr in order to perform deferred attribution. If one or more actual
805 * deferred types are stuck, they are placed in a queue and revisited later
806 * after the remainder of the arguments have been seen. If this is not sufficient
807 * to 'unstuck' the argument, a cyclic inference error is called out.
808 *
809 * A method check handler (see above) is used in order to report errors.
810 */
811 MethodCheck resolveMethodCheck = new AbstractMethodCheck() {
813 @Override
814 void checkArg(DiagnosticPosition pos, boolean varargs, Type actual, Type formal, DeferredAttrContext deferredAttrContext, Warner warn) {
815 ResultInfo mresult = methodCheckResult(varargs, formal, deferredAttrContext, warn);
816 mresult.check(pos, actual);
817 }
819 @Override
820 public void argumentsAcceptable(final Env<AttrContext> env,
821 DeferredAttrContext deferredAttrContext,
822 List<Type> argtypes,
823 List<Type> formals,
824 Warner warn) {
825 super.argumentsAcceptable(env, deferredAttrContext, argtypes, formals, warn);
826 //should we expand formals?
827 if (deferredAttrContext.phase.isVarargsRequired()) {
828 //check varargs element type accessibility
829 varargsAccessible(env, types.elemtype(formals.last()),
830 deferredAttrContext.inferenceContext);
831 }
832 }
834 private void varargsAccessible(final Env<AttrContext> env, final Type t, final InferenceContext inferenceContext) {
835 if (inferenceContext.free(t)) {
836 inferenceContext.addFreeTypeListener(List.of(t), new FreeTypeListener() {
837 @Override
838 public void typesInferred(InferenceContext inferenceContext) {
839 varargsAccessible(env, inferenceContext.asInstType(t), inferenceContext);
840 }
841 });
842 } else {
843 if (!isAccessible(env, t)) {
844 Symbol location = env.enclClass.sym;
845 reportMC(env.tree, MethodCheckDiag.INACCESSIBLE_VARARGS, inferenceContext, t, Kinds.kindName(location), location);
846 }
847 }
848 }
850 private ResultInfo methodCheckResult(final boolean varargsCheck, Type to,
851 final DeferredAttr.DeferredAttrContext deferredAttrContext, Warner rsWarner) {
852 CheckContext checkContext = new MethodCheckContext(!deferredAttrContext.phase.isBoxingRequired(), deferredAttrContext, rsWarner) {
853 MethodCheckDiag methodDiag = varargsCheck ?
854 MethodCheckDiag.VARARG_MISMATCH : MethodCheckDiag.ARG_MISMATCH;
856 @Override
857 public void report(DiagnosticPosition pos, JCDiagnostic details) {
858 reportMC(pos, methodDiag, deferredAttrContext.inferenceContext, details);
859 }
860 };
861 return new MethodResultInfo(to, checkContext);
862 }
864 @Override
865 public MethodCheck mostSpecificCheck(List<Type> actuals, boolean strict) {
866 return new MostSpecificCheck(strict, actuals);
867 }
868 };
870 class MethodReferenceCheck extends AbstractMethodCheck {
872 InferenceContext pendingInferenceContext;
874 MethodReferenceCheck(InferenceContext pendingInferenceContext) {
875 this.pendingInferenceContext = pendingInferenceContext;
876 }
878 @Override
879 void checkArg(DiagnosticPosition pos, boolean varargs, Type actual, Type formal, DeferredAttrContext deferredAttrContext, Warner warn) {
880 ResultInfo mresult = methodCheckResult(varargs, formal, deferredAttrContext, warn);
881 mresult.check(pos, actual);
882 }
884 private ResultInfo methodCheckResult(final boolean varargsCheck, Type to,
885 final DeferredAttr.DeferredAttrContext deferredAttrContext, Warner rsWarner) {
886 CheckContext checkContext = new MethodCheckContext(!deferredAttrContext.phase.isBoxingRequired(), deferredAttrContext, rsWarner) {
887 MethodCheckDiag methodDiag = varargsCheck ?
888 MethodCheckDiag.VARARG_MISMATCH : MethodCheckDiag.ARG_MISMATCH;
890 @Override
891 public boolean compatible(Type found, Type req, Warner warn) {
892 found = pendingInferenceContext.asFree(found);
893 req = infer.returnConstraintTarget(found, req);
894 return super.compatible(found, req, warn);
895 }
897 @Override
898 public void report(DiagnosticPosition pos, JCDiagnostic details) {
899 reportMC(pos, methodDiag, deferredAttrContext.inferenceContext, details);
900 }
901 };
902 return new MethodResultInfo(to, checkContext);
903 }
905 @Override
906 public MethodCheck mostSpecificCheck(List<Type> actuals, boolean strict) {
907 return new MostSpecificCheck(strict, actuals);
908 }
909 };
911 /**
912 * Check context to be used during method applicability checks. A method check
913 * context might contain inference variables.
914 */
915 abstract class MethodCheckContext implements CheckContext {
917 boolean strict;
918 DeferredAttrContext deferredAttrContext;
919 Warner rsWarner;
921 public MethodCheckContext(boolean strict, DeferredAttrContext deferredAttrContext, Warner rsWarner) {
922 this.strict = strict;
923 this.deferredAttrContext = deferredAttrContext;
924 this.rsWarner = rsWarner;
925 }
927 public boolean compatible(Type found, Type req, Warner warn) {
928 return strict ?
929 types.isSubtypeUnchecked(found, deferredAttrContext.inferenceContext.asFree(req), warn) :
930 types.isConvertible(found, deferredAttrContext.inferenceContext.asFree(req), warn);
931 }
933 public void report(DiagnosticPosition pos, JCDiagnostic details) {
934 throw inapplicableMethodException.setMessage(details);
935 }
937 public Warner checkWarner(DiagnosticPosition pos, Type found, Type req) {
938 return rsWarner;
939 }
941 public InferenceContext inferenceContext() {
942 return deferredAttrContext.inferenceContext;
943 }
945 public DeferredAttrContext deferredAttrContext() {
946 return deferredAttrContext;
947 }
948 }
950 /**
951 * ResultInfo class to be used during method applicability checks. Check
952 * for deferred types goes through special path.
953 */
954 class MethodResultInfo extends ResultInfo {
956 public MethodResultInfo(Type pt, CheckContext checkContext) {
957 attr.super(VAL, pt, checkContext);
958 }
960 @Override
961 protected Type check(DiagnosticPosition pos, Type found) {
962 if (found.hasTag(DEFERRED)) {
963 DeferredType dt = (DeferredType)found;
964 return dt.check(this);
965 } else {
966 return super.check(pos, chk.checkNonVoid(pos, types.capture(U(found.baseType()))));
967 }
968 }
970 /**
971 * javac has a long-standing 'simplification' (see 6391995):
972 * given an actual argument type, the method check is performed
973 * on its upper bound. This leads to inconsistencies when an
974 * argument type is checked against itself. For example, given
975 * a type-variable T, it is not true that {@code U(T) <: T},
976 * so we need to guard against that.
977 */
978 private Type U(Type found) {
979 return found == pt ?
980 found : types.upperBound(found);
981 }
983 @Override
984 protected MethodResultInfo dup(Type newPt) {
985 return new MethodResultInfo(newPt, checkContext);
986 }
988 @Override
989 protected ResultInfo dup(CheckContext newContext) {
990 return new MethodResultInfo(pt, newContext);
991 }
992 }
994 /**
995 * Most specific method applicability routine. Given a list of actual types A,
996 * a list of formal types F1, and a list of formal types F2, the routine determines
997 * as to whether the types in F1 can be considered more specific than those in F2 w.r.t.
998 * argument types A.
999 */
1000 class MostSpecificCheck implements MethodCheck {
1002 boolean strict;
1003 List<Type> actuals;
1005 MostSpecificCheck(boolean strict, List<Type> actuals) {
1006 this.strict = strict;
1007 this.actuals = actuals;
1008 }
1010 @Override
1011 public void argumentsAcceptable(final Env<AttrContext> env,
1012 DeferredAttrContext deferredAttrContext,
1013 List<Type> formals1,
1014 List<Type> formals2,
1015 Warner warn) {
1016 formals2 = adjustArgs(formals2, deferredAttrContext.msym, formals1.length(), deferredAttrContext.phase.isVarargsRequired());
1017 while (formals2.nonEmpty()) {
1018 ResultInfo mresult = methodCheckResult(formals2.head, deferredAttrContext, warn, actuals.head);
1019 mresult.check(null, formals1.head);
1020 formals1 = formals1.tail;
1021 formals2 = formals2.tail;
1022 actuals = actuals.isEmpty() ? actuals : actuals.tail;
1023 }
1024 }
1026 /**
1027 * Create a method check context to be used during the most specific applicability check
1028 */
1029 ResultInfo methodCheckResult(Type to, DeferredAttr.DeferredAttrContext deferredAttrContext,
1030 Warner rsWarner, Type actual) {
1031 return attr.new ResultInfo(Kinds.VAL, to,
1032 new MostSpecificCheckContext(strict, deferredAttrContext, rsWarner, actual));
1033 }
1035 /**
1036 * Subclass of method check context class that implements most specific
1037 * method conversion. If the actual type under analysis is a deferred type
1038 * a full blown structural analysis is carried out.
1039 */
1040 class MostSpecificCheckContext extends MethodCheckContext {
1042 Type actual;
1044 public MostSpecificCheckContext(boolean strict, DeferredAttrContext deferredAttrContext, Warner rsWarner, Type actual) {
1045 super(strict, deferredAttrContext, rsWarner);
1046 this.actual = actual;
1047 }
1049 public boolean compatible(Type found, Type req, Warner warn) {
1050 if (!allowStructuralMostSpecific || actual == null) {
1051 return super.compatible(found, req, warn);
1052 } else {
1053 switch (actual.getTag()) {
1054 case DEFERRED:
1055 DeferredType dt = (DeferredType) actual;
1056 DeferredType.SpeculativeCache.Entry e = dt.speculativeCache.get(deferredAttrContext.msym, deferredAttrContext.phase);
1057 return (e == null || e.speculativeTree == deferredAttr.stuckTree)
1058 ? super.compatible(found, req, warn) :
1059 mostSpecific(found, req, e.speculativeTree, warn);
1060 default:
1061 return standaloneMostSpecific(found, req, actual, warn);
1062 }
1063 }
1064 }
1066 private boolean mostSpecific(Type t, Type s, JCTree tree, Warner warn) {
1067 MostSpecificChecker msc = new MostSpecificChecker(t, s, warn);
1068 msc.scan(tree);
1069 return msc.result;
1070 }
1072 boolean polyMostSpecific(Type t1, Type t2, Warner warn) {
1073 return (!t1.isPrimitive() && t2.isPrimitive())
1074 ? true : super.compatible(t1, t2, warn);
1075 }
1077 boolean standaloneMostSpecific(Type t1, Type t2, Type exprType, Warner warn) {
1078 return (exprType.isPrimitive() == t1.isPrimitive()
1079 && exprType.isPrimitive() != t2.isPrimitive())
1080 ? true : super.compatible(t1, t2, warn);
1081 }
1083 /**
1084 * Structural checker for most specific.
1085 */
1086 class MostSpecificChecker extends DeferredAttr.PolyScanner {
1088 final Type t;
1089 final Type s;
1090 final Warner warn;
1091 boolean result;
1093 MostSpecificChecker(Type t, Type s, Warner warn) {
1094 this.t = t;
1095 this.s = s;
1096 this.warn = warn;
1097 result = true;
1098 }
1100 @Override
1101 void skip(JCTree tree) {
1102 result &= standaloneMostSpecific(t, s, tree.type, warn);
1103 }
1105 @Override
1106 public void visitConditional(JCConditional tree) {
1107 if (tree.polyKind == PolyKind.STANDALONE) {
1108 result &= standaloneMostSpecific(t, s, tree.type, warn);
1109 } else {
1110 super.visitConditional(tree);
1111 }
1112 }
1114 @Override
1115 public void visitApply(JCMethodInvocation tree) {
1116 result &= (tree.polyKind == PolyKind.STANDALONE)
1117 ? standaloneMostSpecific(t, s, tree.type, warn)
1118 : polyMostSpecific(t, s, warn);
1119 }
1121 @Override
1122 public void visitNewClass(JCNewClass tree) {
1123 result &= (tree.polyKind == PolyKind.STANDALONE)
1124 ? standaloneMostSpecific(t, s, tree.type, warn)
1125 : polyMostSpecific(t, s, warn);
1126 }
1128 @Override
1129 public void visitReference(JCMemberReference tree) {
1130 if (types.isFunctionalInterface(t.tsym) &&
1131 types.isFunctionalInterface(s.tsym)) {
1132 Type desc_t = types.findDescriptorType(t);
1133 Type desc_s = types.findDescriptorType(s);
1134 if (types.isSameTypes(desc_t.getParameterTypes(),
1135 inferenceContext().asFree(desc_s.getParameterTypes()))) {
1136 if (types.asSuper(t, s.tsym) != null ||
1137 types.asSuper(s, t.tsym) != null) {
1138 result &= MostSpecificCheckContext.super.compatible(t, s, warn);
1139 } else if (!desc_s.getReturnType().hasTag(VOID)) {
1140 //perform structural comparison
1141 Type ret_t = desc_t.getReturnType();
1142 Type ret_s = desc_s.getReturnType();
1143 result &= ((tree.refPolyKind == PolyKind.STANDALONE)
1144 ? standaloneMostSpecific(ret_t, ret_s, tree.sym.type.getReturnType(), warn)
1145 : polyMostSpecific(ret_t, ret_s, warn));
1146 } else {
1147 return;
1148 }
1149 }
1150 } else {
1151 result &= false;
1152 }
1153 }
1155 @Override
1156 public void visitLambda(JCLambda tree) {
1157 if (types.isFunctionalInterface(t.tsym) &&
1158 types.isFunctionalInterface(s.tsym)) {
1159 Type desc_t = types.findDescriptorType(t);
1160 Type desc_s = types.findDescriptorType(s);
1161 if (types.isSameTypes(desc_t.getParameterTypes(),
1162 inferenceContext().asFree(desc_s.getParameterTypes()))) {
1163 if (types.asSuper(t, s.tsym) != null ||
1164 types.asSuper(s, t.tsym) != null) {
1165 result &= MostSpecificCheckContext.super.compatible(t, s, warn);
1166 } else if (!desc_s.getReturnType().hasTag(VOID)) {
1167 //perform structural comparison
1168 Type ret_t = desc_t.getReturnType();
1169 Type ret_s = desc_s.getReturnType();
1170 scanLambdaBody(tree, ret_t, ret_s);
1171 } else {
1172 return;
1173 }
1174 }
1175 } else {
1176 result &= false;
1177 }
1178 }
1179 //where
1181 void scanLambdaBody(JCLambda lambda, final Type t, final Type s) {
1182 if (lambda.getBodyKind() == JCTree.JCLambda.BodyKind.EXPRESSION) {
1183 result &= MostSpecificCheckContext.this.mostSpecific(t, s, lambda.body, warn);
1184 } else {
1185 DeferredAttr.LambdaReturnScanner lambdaScanner =
1186 new DeferredAttr.LambdaReturnScanner() {
1187 @Override
1188 public void visitReturn(JCReturn tree) {
1189 if (tree.expr != null) {
1190 result &= MostSpecificCheckContext.this.mostSpecific(t, s, tree.expr, warn);
1191 }
1192 }
1193 };
1194 lambdaScanner.scan(lambda.body);
1195 }
1196 }
1197 }
1198 }
1200 public MethodCheck mostSpecificCheck(List<Type> actuals, boolean strict) {
1201 Assert.error("Cannot get here!");
1202 return null;
1203 }
1204 }
1206 public static class InapplicableMethodException extends RuntimeException {
1207 private static final long serialVersionUID = 0;
1209 JCDiagnostic diagnostic;
1210 JCDiagnostic.Factory diags;
1212 InapplicableMethodException(JCDiagnostic.Factory diags) {
1213 this.diagnostic = null;
1214 this.diags = diags;
1215 }
1216 InapplicableMethodException setMessage() {
1217 return setMessage((JCDiagnostic)null);
1218 }
1219 InapplicableMethodException setMessage(String key) {
1220 return setMessage(key != null ? diags.fragment(key) : null);
1221 }
1222 InapplicableMethodException setMessage(String key, Object... args) {
1223 return setMessage(key != null ? diags.fragment(key, args) : null);
1224 }
1225 InapplicableMethodException setMessage(JCDiagnostic diag) {
1226 this.diagnostic = diag;
1227 return this;
1228 }
1230 public JCDiagnostic getDiagnostic() {
1231 return diagnostic;
1232 }
1233 }
1234 private final InapplicableMethodException inapplicableMethodException;
1236 /* ***************************************************************************
1237 * Symbol lookup
1238 * the following naming conventions for arguments are used
1239 *
1240 * env is the environment where the symbol was mentioned
1241 * site is the type of which the symbol is a member
1242 * name is the symbol's name
1243 * if no arguments are given
1244 * argtypes are the value arguments, if we search for a method
1245 *
1246 * If no symbol was found, a ResolveError detailing the problem is returned.
1247 ****************************************************************************/
1249 /** Find field. Synthetic fields are always skipped.
1250 * @param env The current environment.
1251 * @param site The original type from where the selection takes place.
1252 * @param name The name of the field.
1253 * @param c The class to search for the field. This is always
1254 * a superclass or implemented interface of site's class.
1255 */
1256 Symbol findField(Env<AttrContext> env,
1257 Type site,
1258 Name name,
1259 TypeSymbol c) {
1260 while (c.type.hasTag(TYPEVAR))
1261 c = c.type.getUpperBound().tsym;
1262 Symbol bestSoFar = varNotFound;
1263 Symbol sym;
1264 Scope.Entry e = c.members().lookup(name);
1265 while (e.scope != null) {
1266 if (e.sym.kind == VAR && (e.sym.flags_field & SYNTHETIC) == 0) {
1267 return isAccessible(env, site, e.sym)
1268 ? e.sym : new AccessError(env, site, e.sym);
1269 }
1270 e = e.next();
1271 }
1272 Type st = types.supertype(c.type);
1273 if (st != null && (st.hasTag(CLASS) || st.hasTag(TYPEVAR))) {
1274 sym = findField(env, site, name, st.tsym);
1275 if (sym.kind < bestSoFar.kind) bestSoFar = sym;
1276 }
1277 for (List<Type> l = types.interfaces(c.type);
1278 bestSoFar.kind != AMBIGUOUS && l.nonEmpty();
1279 l = l.tail) {
1280 sym = findField(env, site, name, l.head.tsym);
1281 if (bestSoFar.exists() && sym.exists() &&
1282 sym.owner != bestSoFar.owner)
1283 bestSoFar = new AmbiguityError(bestSoFar, sym);
1284 else if (sym.kind < bestSoFar.kind)
1285 bestSoFar = sym;
1286 }
1287 return bestSoFar;
1288 }
1290 /** Resolve a field identifier, throw a fatal error if not found.
1291 * @param pos The position to use for error reporting.
1292 * @param env The environment current at the method invocation.
1293 * @param site The type of the qualifying expression, in which
1294 * identifier is searched.
1295 * @param name The identifier's name.
1296 */
1297 public VarSymbol resolveInternalField(DiagnosticPosition pos, Env<AttrContext> env,
1298 Type site, Name name) {
1299 Symbol sym = findField(env, site, name, site.tsym);
1300 if (sym.kind == VAR) return (VarSymbol)sym;
1301 else throw new FatalError(
1302 diags.fragment("fatal.err.cant.locate.field",
1303 name));
1304 }
1306 /** Find unqualified variable or field with given name.
1307 * Synthetic fields always skipped.
1308 * @param env The current environment.
1309 * @param name The name of the variable or field.
1310 */
1311 Symbol findVar(Env<AttrContext> env, Name name) {
1312 Symbol bestSoFar = varNotFound;
1313 Symbol sym;
1314 Env<AttrContext> env1 = env;
1315 boolean staticOnly = false;
1316 while (env1.outer != null) {
1317 if (isStatic(env1)) staticOnly = true;
1318 Scope.Entry e = env1.info.scope.lookup(name);
1319 while (e.scope != null &&
1320 (e.sym.kind != VAR ||
1321 (e.sym.flags_field & SYNTHETIC) != 0))
1322 e = e.next();
1323 sym = (e.scope != null)
1324 ? e.sym
1325 : findField(
1326 env1, env1.enclClass.sym.type, name, env1.enclClass.sym);
1327 if (sym.exists()) {
1328 if (staticOnly &&
1329 sym.kind == VAR &&
1330 sym.owner.kind == TYP &&
1331 (sym.flags() & STATIC) == 0)
1332 return new StaticError(sym);
1333 else
1334 return sym;
1335 } else if (sym.kind < bestSoFar.kind) {
1336 bestSoFar = sym;
1337 }
1339 if ((env1.enclClass.sym.flags() & STATIC) != 0) staticOnly = true;
1340 env1 = env1.outer;
1341 }
1343 sym = findField(env, syms.predefClass.type, name, syms.predefClass);
1344 if (sym.exists())
1345 return sym;
1346 if (bestSoFar.exists())
1347 return bestSoFar;
1349 Symbol origin = null;
1350 for (Scope sc : new Scope[] { env.toplevel.namedImportScope, env.toplevel.starImportScope }) {
1351 Scope.Entry e = sc.lookup(name);
1352 for (; e.scope != null; e = e.next()) {
1353 sym = e.sym;
1354 if (sym.kind != VAR)
1355 continue;
1356 // invariant: sym.kind == VAR
1357 if (bestSoFar.kind < AMBIGUOUS && sym.owner != bestSoFar.owner)
1358 return new AmbiguityError(bestSoFar, sym);
1359 else if (bestSoFar.kind >= VAR) {
1360 origin = e.getOrigin().owner;
1361 bestSoFar = isAccessible(env, origin.type, sym)
1362 ? sym : new AccessError(env, origin.type, sym);
1363 }
1364 }
1365 if (bestSoFar.exists()) break;
1366 }
1367 if (bestSoFar.kind == VAR && bestSoFar.owner.type != origin.type)
1368 return bestSoFar.clone(origin);
1369 else
1370 return bestSoFar;
1371 }
1373 Warner noteWarner = new Warner();
1375 /** Select the best method for a call site among two choices.
1376 * @param env The current environment.
1377 * @param site The original type from where the
1378 * selection takes place.
1379 * @param argtypes The invocation's value arguments,
1380 * @param typeargtypes The invocation's type arguments,
1381 * @param sym Proposed new best match.
1382 * @param bestSoFar Previously found best match.
1383 * @param allowBoxing Allow boxing conversions of arguments.
1384 * @param useVarargs Box trailing arguments into an array for varargs.
1385 */
1386 @SuppressWarnings("fallthrough")
1387 Symbol selectBest(Env<AttrContext> env,
1388 Type site,
1389 List<Type> argtypes,
1390 List<Type> typeargtypes,
1391 Symbol sym,
1392 Symbol bestSoFar,
1393 boolean allowBoxing,
1394 boolean useVarargs,
1395 boolean operator) {
1396 if (sym.kind == ERR ||
1397 !sym.isInheritedIn(site.tsym, types)) {
1398 return bestSoFar;
1399 } else if (useVarargs && (sym.flags() & VARARGS) == 0) {
1400 return bestSoFar.kind >= ERRONEOUS ?
1401 new BadVarargsMethod((ResolveError)bestSoFar) :
1402 bestSoFar;
1403 }
1404 Assert.check(sym.kind < AMBIGUOUS);
1405 try {
1406 Type mt = rawInstantiate(env, site, sym, null, argtypes, typeargtypes,
1407 allowBoxing, useVarargs, types.noWarnings);
1408 if (!operator || verboseResolutionMode.contains(VerboseResolutionMode.PREDEF))
1409 currentResolutionContext.addApplicableCandidate(sym, mt);
1410 } catch (InapplicableMethodException ex) {
1411 if (!operator)
1412 currentResolutionContext.addInapplicableCandidate(sym, ex.getDiagnostic());
1413 switch (bestSoFar.kind) {
1414 case ABSENT_MTH:
1415 return new InapplicableSymbolError(currentResolutionContext);
1416 case WRONG_MTH:
1417 if (operator) return bestSoFar;
1418 bestSoFar = new InapplicableSymbolsError(currentResolutionContext);
1419 default:
1420 return bestSoFar;
1421 }
1422 }
1423 if (!isAccessible(env, site, sym)) {
1424 return (bestSoFar.kind == ABSENT_MTH)
1425 ? new AccessError(env, site, sym)
1426 : bestSoFar;
1427 }
1428 return (bestSoFar.kind > AMBIGUOUS)
1429 ? sym
1430 : mostSpecific(argtypes, sym, bestSoFar, env, site,
1431 allowBoxing && operator, useVarargs);
1432 }
1434 /* Return the most specific of the two methods for a call,
1435 * given that both are accessible and applicable.
1436 * @param m1 A new candidate for most specific.
1437 * @param m2 The previous most specific candidate.
1438 * @param env The current environment.
1439 * @param site The original type from where the selection
1440 * takes place.
1441 * @param allowBoxing Allow boxing conversions of arguments.
1442 * @param useVarargs Box trailing arguments into an array for varargs.
1443 */
1444 Symbol mostSpecific(List<Type> argtypes, Symbol m1,
1445 Symbol m2,
1446 Env<AttrContext> env,
1447 final Type site,
1448 boolean allowBoxing,
1449 boolean useVarargs) {
1450 switch (m2.kind) {
1451 case MTH:
1452 if (m1 == m2) return m1;
1453 boolean m1SignatureMoreSpecific =
1454 signatureMoreSpecific(argtypes, env, site, m1, m2, allowBoxing, useVarargs);
1455 boolean m2SignatureMoreSpecific =
1456 signatureMoreSpecific(argtypes, env, site, m2, m1, allowBoxing, useVarargs);
1457 if (m1SignatureMoreSpecific && m2SignatureMoreSpecific) {
1458 Type mt1 = types.memberType(site, m1);
1459 Type mt2 = types.memberType(site, m2);
1460 if (!types.overrideEquivalent(mt1, mt2))
1461 return ambiguityError(m1, m2);
1463 // same signature; select (a) the non-bridge method, or
1464 // (b) the one that overrides the other, or (c) the concrete
1465 // one, or (d) merge both abstract signatures
1466 if ((m1.flags() & BRIDGE) != (m2.flags() & BRIDGE))
1467 return ((m1.flags() & BRIDGE) != 0) ? m2 : m1;
1469 // if one overrides or hides the other, use it
1470 TypeSymbol m1Owner = (TypeSymbol)m1.owner;
1471 TypeSymbol m2Owner = (TypeSymbol)m2.owner;
1472 if (types.asSuper(m1Owner.type, m2Owner) != null &&
1473 ((m1.owner.flags_field & INTERFACE) == 0 ||
1474 (m2.owner.flags_field & INTERFACE) != 0) &&
1475 m1.overrides(m2, m1Owner, types, false))
1476 return m1;
1477 if (types.asSuper(m2Owner.type, m1Owner) != null &&
1478 ((m2.owner.flags_field & INTERFACE) == 0 ||
1479 (m1.owner.flags_field & INTERFACE) != 0) &&
1480 m2.overrides(m1, m2Owner, types, false))
1481 return m2;
1482 boolean m1Abstract = (m1.flags() & ABSTRACT) != 0;
1483 boolean m2Abstract = (m2.flags() & ABSTRACT) != 0;
1484 if (m1Abstract && !m2Abstract) return m2;
1485 if (m2Abstract && !m1Abstract) return m1;
1486 // both abstract or both concrete
1487 return ambiguityError(m1, m2);
1488 }
1489 if (m1SignatureMoreSpecific) return m1;
1490 if (m2SignatureMoreSpecific) return m2;
1491 return ambiguityError(m1, m2);
1492 case AMBIGUOUS:
1493 //check if m1 is more specific than all ambiguous methods in m2
1494 AmbiguityError e = (AmbiguityError)m2;
1495 for (Symbol s : e.ambiguousSyms) {
1496 if (mostSpecific(argtypes, m1, s, env, site, allowBoxing, useVarargs) != m1) {
1497 return e.addAmbiguousSymbol(m1);
1498 }
1499 }
1500 return m1;
1501 default:
1502 throw new AssertionError();
1503 }
1504 }
1505 //where
1506 private boolean signatureMoreSpecific(List<Type> actuals, Env<AttrContext> env, Type site, Symbol m1, Symbol m2, boolean allowBoxing, boolean useVarargs) {
1507 noteWarner.clear();
1508 int maxLength = Math.max(
1509 Math.max(m1.type.getParameterTypes().length(), actuals.length()),
1510 m2.type.getParameterTypes().length());
1511 MethodResolutionContext prevResolutionContext = currentResolutionContext;
1512 try {
1513 currentResolutionContext = new MethodResolutionContext();
1514 currentResolutionContext.step = prevResolutionContext.step;
1515 currentResolutionContext.methodCheck =
1516 prevResolutionContext.methodCheck.mostSpecificCheck(actuals, !allowBoxing);
1517 Type mst = instantiate(env, site, m2, null,
1518 adjustArgs(types.lowerBounds(types.memberType(site, m1).getParameterTypes()), m1, maxLength, useVarargs), null,
1519 allowBoxing, useVarargs, noteWarner);
1520 return mst != null &&
1521 !noteWarner.hasLint(Lint.LintCategory.UNCHECKED);
1522 } finally {
1523 currentResolutionContext = prevResolutionContext;
1524 }
1525 }
1527 List<Type> adjustArgs(List<Type> args, Symbol msym, int length, boolean allowVarargs) {
1528 if ((msym.flags() & VARARGS) != 0 && allowVarargs) {
1529 Type varargsElem = types.elemtype(args.last());
1530 if (varargsElem == null) {
1531 Assert.error("Bad varargs = " + args.last() + " " + msym);
1532 }
1533 List<Type> newArgs = args.reverse().tail.prepend(varargsElem).reverse();
1534 while (newArgs.length() < length) {
1535 newArgs = newArgs.append(newArgs.last());
1536 }
1537 return newArgs;
1538 } else {
1539 return args;
1540 }
1541 }
1542 //where
1543 Type mostSpecificReturnType(Type mt1, Type mt2) {
1544 Type rt1 = mt1.getReturnType();
1545 Type rt2 = mt2.getReturnType();
1547 if (mt1.hasTag(FORALL) && mt2.hasTag(FORALL)) {
1548 //if both are generic methods, adjust return type ahead of subtyping check
1549 rt1 = types.subst(rt1, mt1.getTypeArguments(), mt2.getTypeArguments());
1550 }
1551 //first use subtyping, then return type substitutability
1552 if (types.isSubtype(rt1, rt2)) {
1553 return mt1;
1554 } else if (types.isSubtype(rt2, rt1)) {
1555 return mt2;
1556 } else if (types.returnTypeSubstitutable(mt1, mt2)) {
1557 return mt1;
1558 } else if (types.returnTypeSubstitutable(mt2, mt1)) {
1559 return mt2;
1560 } else {
1561 return null;
1562 }
1563 }
1564 //where
1565 Symbol ambiguityError(Symbol m1, Symbol m2) {
1566 if (((m1.flags() | m2.flags()) & CLASH) != 0) {
1567 return (m1.flags() & CLASH) == 0 ? m1 : m2;
1568 } else {
1569 return new AmbiguityError(m1, m2);
1570 }
1571 }
1573 Symbol findMethodInScope(Env<AttrContext> env,
1574 Type site,
1575 Name name,
1576 List<Type> argtypes,
1577 List<Type> typeargtypes,
1578 Scope sc,
1579 Symbol bestSoFar,
1580 boolean allowBoxing,
1581 boolean useVarargs,
1582 boolean operator,
1583 boolean abstractok) {
1584 for (Symbol s : sc.getElementsByName(name, new LookupFilter(abstractok))) {
1585 bestSoFar = selectBest(env, site, argtypes, typeargtypes, s,
1586 bestSoFar, allowBoxing, useVarargs, operator);
1587 }
1588 return bestSoFar;
1589 }
1590 //where
1591 class LookupFilter implements Filter<Symbol> {
1593 boolean abstractOk;
1595 LookupFilter(boolean abstractOk) {
1596 this.abstractOk = abstractOk;
1597 }
1599 public boolean accepts(Symbol s) {
1600 long flags = s.flags();
1601 return s.kind == MTH &&
1602 (flags & SYNTHETIC) == 0 &&
1603 (abstractOk ||
1604 (flags & DEFAULT) != 0 ||
1605 (flags & ABSTRACT) == 0);
1606 }
1607 };
1609 /** Find best qualified method matching given name, type and value
1610 * arguments.
1611 * @param env The current environment.
1612 * @param site The original type from where the selection
1613 * takes place.
1614 * @param name The method's name.
1615 * @param argtypes The method's value arguments.
1616 * @param typeargtypes The method's type arguments
1617 * @param allowBoxing Allow boxing conversions of arguments.
1618 * @param useVarargs Box trailing arguments into an array for varargs.
1619 */
1620 Symbol findMethod(Env<AttrContext> env,
1621 Type site,
1622 Name name,
1623 List<Type> argtypes,
1624 List<Type> typeargtypes,
1625 boolean allowBoxing,
1626 boolean useVarargs,
1627 boolean operator) {
1628 Symbol bestSoFar = methodNotFound;
1629 bestSoFar = findMethod(env,
1630 site,
1631 name,
1632 argtypes,
1633 typeargtypes,
1634 site.tsym.type,
1635 bestSoFar,
1636 allowBoxing,
1637 useVarargs,
1638 operator);
1639 return bestSoFar;
1640 }
1641 // where
1642 private Symbol findMethod(Env<AttrContext> env,
1643 Type site,
1644 Name name,
1645 List<Type> argtypes,
1646 List<Type> typeargtypes,
1647 Type intype,
1648 Symbol bestSoFar,
1649 boolean allowBoxing,
1650 boolean useVarargs,
1651 boolean operator) {
1652 @SuppressWarnings({"unchecked","rawtypes"})
1653 List<Type>[] itypes = (List<Type>[])new List[] { List.<Type>nil(), List.<Type>nil() };
1654 InterfaceLookupPhase iphase = InterfaceLookupPhase.ABSTRACT_OK;
1655 for (TypeSymbol s : superclasses(intype)) {
1656 bestSoFar = findMethodInScope(env, site, name, argtypes, typeargtypes,
1657 s.members(), bestSoFar, allowBoxing, useVarargs, operator, true);
1658 if (name == names.init) return bestSoFar;
1659 iphase = (iphase == null) ? null : iphase.update(s, this);
1660 if (iphase != null) {
1661 for (Type itype : types.interfaces(s.type)) {
1662 itypes[iphase.ordinal()] = types.union(types.closure(itype), itypes[iphase.ordinal()]);
1663 }
1664 }
1665 }
1667 Symbol concrete = bestSoFar.kind < ERR &&
1668 (bestSoFar.flags() & ABSTRACT) == 0 ?
1669 bestSoFar : methodNotFound;
1671 for (InterfaceLookupPhase iphase2 : InterfaceLookupPhase.values()) {
1672 if (iphase2 == InterfaceLookupPhase.DEFAULT_OK && !allowDefaultMethods) break;
1673 //keep searching for abstract methods
1674 for (Type itype : itypes[iphase2.ordinal()]) {
1675 if (!itype.isInterface()) continue; //skip j.l.Object (included by Types.closure())
1676 if (iphase2 == InterfaceLookupPhase.DEFAULT_OK &&
1677 (itype.tsym.flags() & DEFAULT) == 0) continue;
1678 bestSoFar = findMethodInScope(env, site, name, argtypes, typeargtypes,
1679 itype.tsym.members(), bestSoFar, allowBoxing, useVarargs, operator, true);
1680 if (concrete != bestSoFar &&
1681 concrete.kind < ERR && bestSoFar.kind < ERR &&
1682 types.isSubSignature(concrete.type, bestSoFar.type)) {
1683 //this is an hack - as javac does not do full membership checks
1684 //most specific ends up comparing abstract methods that might have
1685 //been implemented by some concrete method in a subclass and,
1686 //because of raw override, it is possible for an abstract method
1687 //to be more specific than the concrete method - so we need
1688 //to explicitly call that out (see CR 6178365)
1689 bestSoFar = concrete;
1690 }
1691 }
1692 }
1693 return bestSoFar;
1694 }
1696 enum InterfaceLookupPhase {
1697 ABSTRACT_OK() {
1698 @Override
1699 InterfaceLookupPhase update(Symbol s, Resolve rs) {
1700 //We should not look for abstract methods if receiver is a concrete class
1701 //(as concrete classes are expected to implement all abstracts coming
1702 //from superinterfaces)
1703 if ((s.flags() & (ABSTRACT | INTERFACE | ENUM)) != 0) {
1704 return this;
1705 } else if (rs.allowDefaultMethods) {
1706 return DEFAULT_OK;
1707 } else {
1708 return null;
1709 }
1710 }
1711 },
1712 DEFAULT_OK() {
1713 @Override
1714 InterfaceLookupPhase update(Symbol s, Resolve rs) {
1715 return this;
1716 }
1717 };
1719 abstract InterfaceLookupPhase update(Symbol s, Resolve rs);
1720 }
1722 /**
1723 * Return an Iterable object to scan the superclasses of a given type.
1724 * It's crucial that the scan is done lazily, as we don't want to accidentally
1725 * access more supertypes than strictly needed (as this could trigger completion
1726 * errors if some of the not-needed supertypes are missing/ill-formed).
1727 */
1728 Iterable<TypeSymbol> superclasses(final Type intype) {
1729 return new Iterable<TypeSymbol>() {
1730 public Iterator<TypeSymbol> iterator() {
1731 return new Iterator<TypeSymbol>() {
1733 List<TypeSymbol> seen = List.nil();
1734 TypeSymbol currentSym = symbolFor(intype);
1735 TypeSymbol prevSym = null;
1737 public boolean hasNext() {
1738 if (currentSym == syms.noSymbol) {
1739 currentSym = symbolFor(types.supertype(prevSym.type));
1740 }
1741 return currentSym != null;
1742 }
1744 public TypeSymbol next() {
1745 prevSym = currentSym;
1746 currentSym = syms.noSymbol;
1747 Assert.check(prevSym != null || prevSym != syms.noSymbol);
1748 return prevSym;
1749 }
1751 public void remove() {
1752 throw new UnsupportedOperationException();
1753 }
1755 TypeSymbol symbolFor(Type t) {
1756 if (!t.hasTag(CLASS) &&
1757 !t.hasTag(TYPEVAR)) {
1758 return null;
1759 }
1760 while (t.hasTag(TYPEVAR))
1761 t = t.getUpperBound();
1762 if (seen.contains(t.tsym)) {
1763 //degenerate case in which we have a circular
1764 //class hierarchy - because of ill-formed classfiles
1765 return null;
1766 }
1767 seen = seen.prepend(t.tsym);
1768 return t.tsym;
1769 }
1770 };
1771 }
1772 };
1773 }
1775 /** Find unqualified method matching given name, type and value arguments.
1776 * @param env The current environment.
1777 * @param name The method's name.
1778 * @param argtypes The method's value arguments.
1779 * @param typeargtypes The method's type arguments.
1780 * @param allowBoxing Allow boxing conversions of arguments.
1781 * @param useVarargs Box trailing arguments into an array for varargs.
1782 */
1783 Symbol findFun(Env<AttrContext> env, Name name,
1784 List<Type> argtypes, List<Type> typeargtypes,
1785 boolean allowBoxing, boolean useVarargs) {
1786 Symbol bestSoFar = methodNotFound;
1787 Symbol sym;
1788 Env<AttrContext> env1 = env;
1789 boolean staticOnly = false;
1790 while (env1.outer != null) {
1791 if (isStatic(env1)) staticOnly = true;
1792 sym = findMethod(
1793 env1, env1.enclClass.sym.type, name, argtypes, typeargtypes,
1794 allowBoxing, useVarargs, false);
1795 if (sym.exists()) {
1796 if (staticOnly &&
1797 sym.kind == MTH &&
1798 sym.owner.kind == TYP &&
1799 (sym.flags() & STATIC) == 0) return new StaticError(sym);
1800 else return sym;
1801 } else if (sym.kind < bestSoFar.kind) {
1802 bestSoFar = sym;
1803 }
1804 if ((env1.enclClass.sym.flags() & STATIC) != 0) staticOnly = true;
1805 env1 = env1.outer;
1806 }
1808 sym = findMethod(env, syms.predefClass.type, name, argtypes,
1809 typeargtypes, allowBoxing, useVarargs, false);
1810 if (sym.exists())
1811 return sym;
1813 Scope.Entry e = env.toplevel.namedImportScope.lookup(name);
1814 for (; e.scope != null; e = e.next()) {
1815 sym = e.sym;
1816 Type origin = e.getOrigin().owner.type;
1817 if (sym.kind == MTH) {
1818 if (e.sym.owner.type != origin)
1819 sym = sym.clone(e.getOrigin().owner);
1820 if (!isAccessible(env, origin, sym))
1821 sym = new AccessError(env, origin, sym);
1822 bestSoFar = selectBest(env, origin,
1823 argtypes, typeargtypes,
1824 sym, bestSoFar,
1825 allowBoxing, useVarargs, false);
1826 }
1827 }
1828 if (bestSoFar.exists())
1829 return bestSoFar;
1831 e = env.toplevel.starImportScope.lookup(name);
1832 for (; e.scope != null; e = e.next()) {
1833 sym = e.sym;
1834 Type origin = e.getOrigin().owner.type;
1835 if (sym.kind == MTH) {
1836 if (e.sym.owner.type != origin)
1837 sym = sym.clone(e.getOrigin().owner);
1838 if (!isAccessible(env, origin, sym))
1839 sym = new AccessError(env, origin, sym);
1840 bestSoFar = selectBest(env, origin,
1841 argtypes, typeargtypes,
1842 sym, bestSoFar,
1843 allowBoxing, useVarargs, false);
1844 }
1845 }
1846 return bestSoFar;
1847 }
1849 /** Load toplevel or member class with given fully qualified name and
1850 * verify that it is accessible.
1851 * @param env The current environment.
1852 * @param name The fully qualified name of the class to be loaded.
1853 */
1854 Symbol loadClass(Env<AttrContext> env, Name name) {
1855 try {
1856 ClassSymbol c = reader.loadClass(name);
1857 return isAccessible(env, c) ? c : new AccessError(c);
1858 } catch (ClassReader.BadClassFile err) {
1859 throw err;
1860 } catch (CompletionFailure ex) {
1861 return typeNotFound;
1862 }
1863 }
1866 /**
1867 * Find a type declared in a scope (not inherited). Return null
1868 * if none is found.
1869 * @param env The current environment.
1870 * @param site The original type from where the selection takes
1871 * place.
1872 * @param name The type's name.
1873 * @param c The class to search for the member type. This is
1874 * always a superclass or implemented interface of
1875 * site's class.
1876 */
1877 Symbol findImmediateMemberType(Env<AttrContext> env,
1878 Type site,
1879 Name name,
1880 TypeSymbol c) {
1881 Scope.Entry e = c.members().lookup(name);
1882 while (e.scope != null) {
1883 if (e.sym.kind == TYP) {
1884 return isAccessible(env, site, e.sym)
1885 ? e.sym
1886 : new AccessError(env, site, e.sym);
1887 }
1888 e = e.next();
1889 }
1890 return typeNotFound;
1891 }
1893 /** Find a member type inherited from a superclass or interface.
1894 * @param env The current environment.
1895 * @param site The original type from where the selection takes
1896 * place.
1897 * @param name The type's name.
1898 * @param c The class to search for the member type. This is
1899 * always a superclass or implemented interface of
1900 * site's class.
1901 */
1902 Symbol findInheritedMemberType(Env<AttrContext> env,
1903 Type site,
1904 Name name,
1905 TypeSymbol c) {
1906 Symbol bestSoFar = typeNotFound;
1907 Symbol sym;
1908 Type st = types.supertype(c.type);
1909 if (st != null && st.hasTag(CLASS)) {
1910 sym = findMemberType(env, site, name, st.tsym);
1911 if (sym.kind < bestSoFar.kind) bestSoFar = sym;
1912 }
1913 for (List<Type> l = types.interfaces(c.type);
1914 bestSoFar.kind != AMBIGUOUS && l.nonEmpty();
1915 l = l.tail) {
1916 sym = findMemberType(env, site, name, l.head.tsym);
1917 if (bestSoFar.kind < AMBIGUOUS && sym.kind < AMBIGUOUS &&
1918 sym.owner != bestSoFar.owner)
1919 bestSoFar = new AmbiguityError(bestSoFar, sym);
1920 else if (sym.kind < bestSoFar.kind)
1921 bestSoFar = sym;
1922 }
1923 return bestSoFar;
1924 }
1926 /** Find qualified member type.
1927 * @param env The current environment.
1928 * @param site The original type from where the selection takes
1929 * place.
1930 * @param name The type's name.
1931 * @param c The class to search for the member type. This is
1932 * always a superclass or implemented interface of
1933 * site's class.
1934 */
1935 Symbol findMemberType(Env<AttrContext> env,
1936 Type site,
1937 Name name,
1938 TypeSymbol c) {
1939 Symbol sym = findImmediateMemberType(env, site, name, c);
1941 if (sym != typeNotFound)
1942 return sym;
1944 return findInheritedMemberType(env, site, name, c);
1946 }
1948 /** Find a global type in given scope and load corresponding class.
1949 * @param env The current environment.
1950 * @param scope The scope in which to look for the type.
1951 * @param name The type's name.
1952 */
1953 Symbol findGlobalType(Env<AttrContext> env, Scope scope, Name name) {
1954 Symbol bestSoFar = typeNotFound;
1955 for (Scope.Entry e = scope.lookup(name); e.scope != null; e = e.next()) {
1956 Symbol sym = loadClass(env, e.sym.flatName());
1957 if (bestSoFar.kind == TYP && sym.kind == TYP &&
1958 bestSoFar != sym)
1959 return new AmbiguityError(bestSoFar, sym);
1960 else if (sym.kind < bestSoFar.kind)
1961 bestSoFar = sym;
1962 }
1963 return bestSoFar;
1964 }
1966 Symbol findTypeVar(Env<AttrContext> env, Name name, boolean staticOnly) {
1967 for (Scope.Entry e = env.info.scope.lookup(name);
1968 e.scope != null;
1969 e = e.next()) {
1970 if (e.sym.kind == TYP) {
1971 if (staticOnly &&
1972 e.sym.type.hasTag(TYPEVAR) &&
1973 e.sym.owner.kind == TYP)
1974 return new StaticError(e.sym);
1975 return e.sym;
1976 }
1977 }
1978 return typeNotFound;
1979 }
1981 /** Find an unqualified type symbol.
1982 * @param env The current environment.
1983 * @param name The type's name.
1984 */
1985 Symbol findType(Env<AttrContext> env, Name name) {
1986 Symbol bestSoFar = typeNotFound;
1987 Symbol sym;
1988 boolean staticOnly = false;
1989 for (Env<AttrContext> env1 = env; env1.outer != null; env1 = env1.outer) {
1990 if (isStatic(env1)) staticOnly = true;
1991 // First, look for a type variable and the first member type
1992 final Symbol tyvar = findTypeVar(env1, name, staticOnly);
1993 sym = findImmediateMemberType(env1, env1.enclClass.sym.type,
1994 name, env1.enclClass.sym);
1996 // Return the type variable if we have it, and have no
1997 // immediate member, OR the type variable is for a method.
1998 if (tyvar != typeNotFound) {
1999 if (sym == typeNotFound ||
2000 (tyvar.kind == TYP && tyvar.exists() &&
2001 tyvar.owner.kind == MTH))
2002 return tyvar;
2003 }
2005 // If the environment is a class def, finish up,
2006 // otherwise, do the entire findMemberType
2007 if (sym == typeNotFound)
2008 sym = findInheritedMemberType(env1, env1.enclClass.sym.type,
2009 name, env1.enclClass.sym);
2011 if (staticOnly && sym.kind == TYP &&
2012 sym.type.hasTag(CLASS) &&
2013 sym.type.getEnclosingType().hasTag(CLASS) &&
2014 env1.enclClass.sym.type.isParameterized() &&
2015 sym.type.getEnclosingType().isParameterized())
2016 return new StaticError(sym);
2017 else if (sym.exists()) return sym;
2018 else if (sym.kind < bestSoFar.kind) bestSoFar = sym;
2020 JCClassDecl encl = env1.baseClause ? (JCClassDecl)env1.tree : env1.enclClass;
2021 if ((encl.sym.flags() & STATIC) != 0)
2022 staticOnly = true;
2023 }
2025 if (!env.tree.hasTag(IMPORT)) {
2026 sym = findGlobalType(env, env.toplevel.namedImportScope, name);
2027 if (sym.exists()) return sym;
2028 else if (sym.kind < bestSoFar.kind) bestSoFar = sym;
2030 sym = findGlobalType(env, env.toplevel.packge.members(), name);
2031 if (sym.exists()) return sym;
2032 else if (sym.kind < bestSoFar.kind) bestSoFar = sym;
2034 sym = findGlobalType(env, env.toplevel.starImportScope, name);
2035 if (sym.exists()) return sym;
2036 else if (sym.kind < bestSoFar.kind) bestSoFar = sym;
2037 }
2039 return bestSoFar;
2040 }
2042 /** Find an unqualified identifier which matches a specified kind set.
2043 * @param env The current environment.
2044 * @param name The identifier's name.
2045 * @param kind Indicates the possible symbol kinds
2046 * (a subset of VAL, TYP, PCK).
2047 */
2048 Symbol findIdent(Env<AttrContext> env, Name name, int kind) {
2049 Symbol bestSoFar = typeNotFound;
2050 Symbol sym;
2052 if ((kind & VAR) != 0) {
2053 sym = findVar(env, name);
2054 if (sym.exists()) return sym;
2055 else if (sym.kind < bestSoFar.kind) bestSoFar = sym;
2056 }
2058 if ((kind & TYP) != 0) {
2059 sym = findType(env, name);
2060 if (sym.kind==TYP) {
2061 reportDependence(env.enclClass.sym, sym);
2062 }
2063 if (sym.exists()) return sym;
2064 else if (sym.kind < bestSoFar.kind) bestSoFar = sym;
2065 }
2067 if ((kind & PCK) != 0) return reader.enterPackage(name);
2068 else return bestSoFar;
2069 }
2071 /** Report dependencies.
2072 * @param from The enclosing class sym
2073 * @param to The found identifier that the class depends on.
2074 */
2075 public void reportDependence(Symbol from, Symbol to) {
2076 // Override if you want to collect the reported dependencies.
2077 }
2079 /** Find an identifier in a package which matches a specified kind set.
2080 * @param env The current environment.
2081 * @param name The identifier's name.
2082 * @param kind Indicates the possible symbol kinds
2083 * (a nonempty subset of TYP, PCK).
2084 */
2085 Symbol findIdentInPackage(Env<AttrContext> env, TypeSymbol pck,
2086 Name name, int kind) {
2087 Name fullname = TypeSymbol.formFullName(name, pck);
2088 Symbol bestSoFar = typeNotFound;
2089 PackageSymbol pack = null;
2090 if ((kind & PCK) != 0) {
2091 pack = reader.enterPackage(fullname);
2092 if (pack.exists()) return pack;
2093 }
2094 if ((kind & TYP) != 0) {
2095 Symbol sym = loadClass(env, fullname);
2096 if (sym.exists()) {
2097 // don't allow programs to use flatnames
2098 if (name == sym.name) return sym;
2099 }
2100 else if (sym.kind < bestSoFar.kind) bestSoFar = sym;
2101 }
2102 return (pack != null) ? pack : bestSoFar;
2103 }
2105 /** Find an identifier among the members of a given type `site'.
2106 * @param env The current environment.
2107 * @param site The type containing the symbol to be found.
2108 * @param name The identifier's name.
2109 * @param kind Indicates the possible symbol kinds
2110 * (a subset of VAL, TYP).
2111 */
2112 Symbol findIdentInType(Env<AttrContext> env, Type site,
2113 Name name, int kind) {
2114 Symbol bestSoFar = typeNotFound;
2115 Symbol sym;
2116 if ((kind & VAR) != 0) {
2117 sym = findField(env, site, name, site.tsym);
2118 if (sym.exists()) return sym;
2119 else if (sym.kind < bestSoFar.kind) bestSoFar = sym;
2120 }
2122 if ((kind & TYP) != 0) {
2123 sym = findMemberType(env, site, name, site.tsym);
2124 if (sym.exists()) return sym;
2125 else if (sym.kind < bestSoFar.kind) bestSoFar = sym;
2126 }
2127 return bestSoFar;
2128 }
2130 /* ***************************************************************************
2131 * Access checking
2132 * The following methods convert ResolveErrors to ErrorSymbols, issuing
2133 * an error message in the process
2134 ****************************************************************************/
2136 /** If `sym' is a bad symbol: report error and return errSymbol
2137 * else pass through unchanged,
2138 * additional arguments duplicate what has been used in trying to find the
2139 * symbol {@literal (--> flyweight pattern)}. This improves performance since we
2140 * expect misses to happen frequently.
2141 *
2142 * @param sym The symbol that was found, or a ResolveError.
2143 * @param pos The position to use for error reporting.
2144 * @param location The symbol the served as a context for this lookup
2145 * @param site The original type from where the selection took place.
2146 * @param name The symbol's name.
2147 * @param qualified Did we get here through a qualified expression resolution?
2148 * @param argtypes The invocation's value arguments,
2149 * if we looked for a method.
2150 * @param typeargtypes The invocation's type arguments,
2151 * if we looked for a method.
2152 * @param logResolveHelper helper class used to log resolve errors
2153 */
2154 Symbol accessInternal(Symbol sym,
2155 DiagnosticPosition pos,
2156 Symbol location,
2157 Type site,
2158 Name name,
2159 boolean qualified,
2160 List<Type> argtypes,
2161 List<Type> typeargtypes,
2162 LogResolveHelper logResolveHelper) {
2163 if (sym.kind >= AMBIGUOUS) {
2164 ResolveError errSym = (ResolveError)sym;
2165 sym = errSym.access(name, qualified ? site.tsym : syms.noSymbol);
2166 argtypes = logResolveHelper.getArgumentTypes(errSym, sym, name, argtypes);
2167 if (logResolveHelper.resolveDiagnosticNeeded(site, argtypes, typeargtypes)) {
2168 logResolveError(errSym, pos, location, site, name, argtypes, typeargtypes);
2169 }
2170 }
2171 return sym;
2172 }
2174 /**
2175 * Variant of the generalized access routine, to be used for generating method
2176 * resolution diagnostics
2177 */
2178 Symbol accessMethod(Symbol sym,
2179 DiagnosticPosition pos,
2180 Symbol location,
2181 Type site,
2182 Name name,
2183 boolean qualified,
2184 List<Type> argtypes,
2185 List<Type> typeargtypes) {
2186 return accessInternal(sym, pos, location, site, name, qualified, argtypes, typeargtypes, methodLogResolveHelper);
2187 }
2189 /** Same as original accessMethod(), but without location.
2190 */
2191 Symbol accessMethod(Symbol sym,
2192 DiagnosticPosition pos,
2193 Type site,
2194 Name name,
2195 boolean qualified,
2196 List<Type> argtypes,
2197 List<Type> typeargtypes) {
2198 return accessMethod(sym, pos, site.tsym, site, name, qualified, argtypes, typeargtypes);
2199 }
2201 /**
2202 * Variant of the generalized access routine, to be used for generating variable,
2203 * type resolution diagnostics
2204 */
2205 Symbol accessBase(Symbol sym,
2206 DiagnosticPosition pos,
2207 Symbol location,
2208 Type site,
2209 Name name,
2210 boolean qualified) {
2211 return accessInternal(sym, pos, location, site, name, qualified, List.<Type>nil(), null, basicLogResolveHelper);
2212 }
2214 /** Same as original accessBase(), but without location.
2215 */
2216 Symbol accessBase(Symbol sym,
2217 DiagnosticPosition pos,
2218 Type site,
2219 Name name,
2220 boolean qualified) {
2221 return accessBase(sym, pos, site.tsym, site, name, qualified);
2222 }
2224 interface LogResolveHelper {
2225 boolean resolveDiagnosticNeeded(Type site, List<Type> argtypes, List<Type> typeargtypes);
2226 List<Type> getArgumentTypes(ResolveError errSym, Symbol accessedSym, Name name, List<Type> argtypes);
2227 }
2229 LogResolveHelper basicLogResolveHelper = new LogResolveHelper() {
2230 public boolean resolveDiagnosticNeeded(Type site, List<Type> argtypes, List<Type> typeargtypes) {
2231 return !site.isErroneous();
2232 }
2233 public List<Type> getArgumentTypes(ResolveError errSym, Symbol accessedSym, Name name, List<Type> argtypes) {
2234 return argtypes;
2235 }
2236 };
2238 LogResolveHelper methodLogResolveHelper = new LogResolveHelper() {
2239 public boolean resolveDiagnosticNeeded(Type site, List<Type> argtypes, List<Type> typeargtypes) {
2240 return !site.isErroneous() &&
2241 !Type.isErroneous(argtypes) &&
2242 (typeargtypes == null || !Type.isErroneous(typeargtypes));
2243 }
2244 public List<Type> getArgumentTypes(ResolveError errSym, Symbol accessedSym, Name name, List<Type> argtypes) {
2245 return (syms.operatorNames.contains(name)) ?
2246 argtypes :
2247 Type.map(argtypes, new ResolveDeferredRecoveryMap(AttrMode.SPECULATIVE, accessedSym, currentResolutionContext.step));
2248 }
2249 };
2251 class ResolveDeferredRecoveryMap extends DeferredAttr.RecoveryDeferredTypeMap {
2253 public ResolveDeferredRecoveryMap(AttrMode mode, Symbol msym, MethodResolutionPhase step) {
2254 deferredAttr.super(mode, msym, step);
2255 }
2257 @Override
2258 protected Type typeOf(DeferredType dt) {
2259 Type res = super.typeOf(dt);
2260 if (!res.isErroneous()) {
2261 switch (TreeInfo.skipParens(dt.tree).getTag()) {
2262 case LAMBDA:
2263 case REFERENCE:
2264 return dt;
2265 case CONDEXPR:
2266 return res == Type.recoveryType ?
2267 dt : res;
2268 }
2269 }
2270 return res;
2271 }
2272 }
2274 /** Check that sym is not an abstract method.
2275 */
2276 void checkNonAbstract(DiagnosticPosition pos, Symbol sym) {
2277 if ((sym.flags() & ABSTRACT) != 0 && (sym.flags() & DEFAULT) == 0)
2278 log.error(pos, "abstract.cant.be.accessed.directly",
2279 kindName(sym), sym, sym.location());
2280 }
2282 /* ***************************************************************************
2283 * Debugging
2284 ****************************************************************************/
2286 /** print all scopes starting with scope s and proceeding outwards.
2287 * used for debugging.
2288 */
2289 public void printscopes(Scope s) {
2290 while (s != null) {
2291 if (s.owner != null)
2292 System.err.print(s.owner + ": ");
2293 for (Scope.Entry e = s.elems; e != null; e = e.sibling) {
2294 if ((e.sym.flags() & ABSTRACT) != 0)
2295 System.err.print("abstract ");
2296 System.err.print(e.sym + " ");
2297 }
2298 System.err.println();
2299 s = s.next;
2300 }
2301 }
2303 void printscopes(Env<AttrContext> env) {
2304 while (env.outer != null) {
2305 System.err.println("------------------------------");
2306 printscopes(env.info.scope);
2307 env = env.outer;
2308 }
2309 }
2311 public void printscopes(Type t) {
2312 while (t.hasTag(CLASS)) {
2313 printscopes(t.tsym.members());
2314 t = types.supertype(t);
2315 }
2316 }
2318 /* ***************************************************************************
2319 * Name resolution
2320 * Naming conventions are as for symbol lookup
2321 * Unlike the find... methods these methods will report access errors
2322 ****************************************************************************/
2324 /** Resolve an unqualified (non-method) identifier.
2325 * @param pos The position to use for error reporting.
2326 * @param env The environment current at the identifier use.
2327 * @param name The identifier's name.
2328 * @param kind The set of admissible symbol kinds for the identifier.
2329 */
2330 Symbol resolveIdent(DiagnosticPosition pos, Env<AttrContext> env,
2331 Name name, int kind) {
2332 return accessBase(
2333 findIdent(env, name, kind),
2334 pos, env.enclClass.sym.type, name, false);
2335 }
2337 /** Resolve an unqualified method identifier.
2338 * @param pos The position to use for error reporting.
2339 * @param env The environment current at the method invocation.
2340 * @param name The identifier's name.
2341 * @param argtypes The types of the invocation's value arguments.
2342 * @param typeargtypes The types of the invocation's type arguments.
2343 */
2344 Symbol resolveMethod(DiagnosticPosition pos,
2345 Env<AttrContext> env,
2346 Name name,
2347 List<Type> argtypes,
2348 List<Type> typeargtypes) {
2349 return lookupMethod(env, pos, env.enclClass.sym, resolveMethodCheck,
2350 new BasicLookupHelper(name, env.enclClass.sym.type, argtypes, typeargtypes) {
2351 @Override
2352 Symbol doLookup(Env<AttrContext> env, MethodResolutionPhase phase) {
2353 return findFun(env, name, argtypes, typeargtypes,
2354 phase.isBoxingRequired(),
2355 phase.isVarargsRequired());
2356 }});
2357 }
2359 /** Resolve a qualified method identifier
2360 * @param pos The position to use for error reporting.
2361 * @param env The environment current at the method invocation.
2362 * @param site The type of the qualifying expression, in which
2363 * identifier is searched.
2364 * @param name The identifier's name.
2365 * @param argtypes The types of the invocation's value arguments.
2366 * @param typeargtypes The types of the invocation's type arguments.
2367 */
2368 Symbol resolveQualifiedMethod(DiagnosticPosition pos, Env<AttrContext> env,
2369 Type site, Name name, List<Type> argtypes,
2370 List<Type> typeargtypes) {
2371 return resolveQualifiedMethod(pos, env, site.tsym, site, name, argtypes, typeargtypes);
2372 }
2373 Symbol resolveQualifiedMethod(DiagnosticPosition pos, Env<AttrContext> env,
2374 Symbol location, Type site, Name name, List<Type> argtypes,
2375 List<Type> typeargtypes) {
2376 return resolveQualifiedMethod(new MethodResolutionContext(), pos, env, location, site, name, argtypes, typeargtypes);
2377 }
2378 private Symbol resolveQualifiedMethod(MethodResolutionContext resolveContext,
2379 DiagnosticPosition pos, Env<AttrContext> env,
2380 Symbol location, Type site, Name name, List<Type> argtypes,
2381 List<Type> typeargtypes) {
2382 return lookupMethod(env, pos, location, resolveContext, new BasicLookupHelper(name, site, argtypes, typeargtypes) {
2383 @Override
2384 Symbol doLookup(Env<AttrContext> env, MethodResolutionPhase phase) {
2385 return findMethod(env, site, name, argtypes, typeargtypes,
2386 phase.isBoxingRequired(),
2387 phase.isVarargsRequired(), false);
2388 }
2389 @Override
2390 Symbol access(Env<AttrContext> env, DiagnosticPosition pos, Symbol location, Symbol sym) {
2391 if (sym.kind >= AMBIGUOUS) {
2392 sym = super.access(env, pos, location, sym);
2393 } else if (allowMethodHandles) {
2394 MethodSymbol msym = (MethodSymbol)sym;
2395 if ((msym.flags() & SIGNATURE_POLYMORPHIC) != 0) {
2396 return findPolymorphicSignatureInstance(env, sym, argtypes);
2397 }
2398 }
2399 return sym;
2400 }
2401 });
2402 }
2404 /** Find or create an implicit method of exactly the given type (after erasure).
2405 * Searches in a side table, not the main scope of the site.
2406 * This emulates the lookup process required by JSR 292 in JVM.
2407 * @param env Attribution environment
2408 * @param spMethod signature polymorphic method - i.e. MH.invokeExact
2409 * @param argtypes The required argument types
2410 */
2411 Symbol findPolymorphicSignatureInstance(Env<AttrContext> env,
2412 final Symbol spMethod,
2413 List<Type> argtypes) {
2414 Type mtype = infer.instantiatePolymorphicSignatureInstance(env,
2415 (MethodSymbol)spMethod, currentResolutionContext, argtypes);
2416 for (Symbol sym : polymorphicSignatureScope.getElementsByName(spMethod.name)) {
2417 if (types.isSameType(mtype, sym.type)) {
2418 return sym;
2419 }
2420 }
2422 // create the desired method
2423 long flags = ABSTRACT | HYPOTHETICAL | spMethod.flags() & Flags.AccessFlags;
2424 Symbol msym = new MethodSymbol(flags, spMethod.name, mtype, spMethod.owner) {
2425 @Override
2426 public Symbol baseSymbol() {
2427 return spMethod;
2428 }
2429 };
2430 polymorphicSignatureScope.enter(msym);
2431 return msym;
2432 }
2434 /** Resolve a qualified method identifier, throw a fatal error if not
2435 * found.
2436 * @param pos The position to use for error reporting.
2437 * @param env The environment current at the method invocation.
2438 * @param site The type of the qualifying expression, in which
2439 * identifier is searched.
2440 * @param name The identifier's name.
2441 * @param argtypes The types of the invocation's value arguments.
2442 * @param typeargtypes The types of the invocation's type arguments.
2443 */
2444 public MethodSymbol resolveInternalMethod(DiagnosticPosition pos, Env<AttrContext> env,
2445 Type site, Name name,
2446 List<Type> argtypes,
2447 List<Type> typeargtypes) {
2448 MethodResolutionContext resolveContext = new MethodResolutionContext();
2449 resolveContext.internalResolution = true;
2450 Symbol sym = resolveQualifiedMethod(resolveContext, pos, env, site.tsym,
2451 site, name, argtypes, typeargtypes);
2452 if (sym.kind == MTH) return (MethodSymbol)sym;
2453 else throw new FatalError(
2454 diags.fragment("fatal.err.cant.locate.meth",
2455 name));
2456 }
2458 /** Resolve constructor.
2459 * @param pos The position to use for error reporting.
2460 * @param env The environment current at the constructor invocation.
2461 * @param site The type of class for which a constructor is searched.
2462 * @param argtypes The types of the constructor invocation's value
2463 * arguments.
2464 * @param typeargtypes The types of the constructor invocation's type
2465 * arguments.
2466 */
2467 Symbol resolveConstructor(DiagnosticPosition pos,
2468 Env<AttrContext> env,
2469 Type site,
2470 List<Type> argtypes,
2471 List<Type> typeargtypes) {
2472 return resolveConstructor(new MethodResolutionContext(), pos, env, site, argtypes, typeargtypes);
2473 }
2475 private Symbol resolveConstructor(MethodResolutionContext resolveContext,
2476 final DiagnosticPosition pos,
2477 Env<AttrContext> env,
2478 Type site,
2479 List<Type> argtypes,
2480 List<Type> typeargtypes) {
2481 return lookupMethod(env, pos, site.tsym, resolveContext, new BasicLookupHelper(names.init, site, argtypes, typeargtypes) {
2482 @Override
2483 Symbol doLookup(Env<AttrContext> env, MethodResolutionPhase phase) {
2484 return findConstructor(pos, env, site, argtypes, typeargtypes,
2485 phase.isBoxingRequired(),
2486 phase.isVarargsRequired());
2487 }
2488 });
2489 }
2491 /** Resolve a constructor, throw a fatal error if not found.
2492 * @param pos The position to use for error reporting.
2493 * @param env The environment current at the method invocation.
2494 * @param site The type to be constructed.
2495 * @param argtypes The types of the invocation's value arguments.
2496 * @param typeargtypes The types of the invocation's type arguments.
2497 */
2498 public MethodSymbol resolveInternalConstructor(DiagnosticPosition pos, Env<AttrContext> env,
2499 Type site,
2500 List<Type> argtypes,
2501 List<Type> typeargtypes) {
2502 MethodResolutionContext resolveContext = new MethodResolutionContext();
2503 resolveContext.internalResolution = true;
2504 Symbol sym = resolveConstructor(resolveContext, pos, env, site, argtypes, typeargtypes);
2505 if (sym.kind == MTH) return (MethodSymbol)sym;
2506 else throw new FatalError(
2507 diags.fragment("fatal.err.cant.locate.ctor", site));
2508 }
2510 Symbol findConstructor(DiagnosticPosition pos, Env<AttrContext> env,
2511 Type site, List<Type> argtypes,
2512 List<Type> typeargtypes,
2513 boolean allowBoxing,
2514 boolean useVarargs) {
2515 Symbol sym = findMethod(env, site,
2516 names.init, argtypes,
2517 typeargtypes, allowBoxing,
2518 useVarargs, false);
2519 chk.checkDeprecated(pos, env.info.scope.owner, sym);
2520 return sym;
2521 }
2523 /** Resolve constructor using diamond inference.
2524 * @param pos The position to use for error reporting.
2525 * @param env The environment current at the constructor invocation.
2526 * @param site The type of class for which a constructor is searched.
2527 * The scope of this class has been touched in attribution.
2528 * @param argtypes The types of the constructor invocation's value
2529 * arguments.
2530 * @param typeargtypes The types of the constructor invocation's type
2531 * arguments.
2532 */
2533 Symbol resolveDiamond(DiagnosticPosition pos,
2534 Env<AttrContext> env,
2535 Type site,
2536 List<Type> argtypes,
2537 List<Type> typeargtypes) {
2538 return lookupMethod(env, pos, site.tsym, resolveMethodCheck,
2539 new BasicLookupHelper(names.init, site, argtypes, typeargtypes) {
2540 @Override
2541 Symbol doLookup(Env<AttrContext> env, MethodResolutionPhase phase) {
2542 return findDiamond(env, site, argtypes, typeargtypes,
2543 phase.isBoxingRequired(),
2544 phase.isVarargsRequired());
2545 }
2546 @Override
2547 Symbol access(Env<AttrContext> env, DiagnosticPosition pos, Symbol location, Symbol sym) {
2548 if (sym.kind >= AMBIGUOUS) {
2549 if (sym.kind != WRONG_MTH && sym.kind != WRONG_MTHS) {
2550 sym = super.access(env, pos, location, sym);
2551 } else {
2552 final JCDiagnostic details = sym.kind == WRONG_MTH ?
2553 ((InapplicableSymbolError)sym).errCandidate().snd :
2554 null;
2555 sym = new InapplicableSymbolError(sym.kind, "diamondError", currentResolutionContext) {
2556 @Override
2557 JCDiagnostic getDiagnostic(DiagnosticType dkind, DiagnosticPosition pos,
2558 Symbol location, Type site, Name name, List<Type> argtypes, List<Type> typeargtypes) {
2559 String key = details == null ?
2560 "cant.apply.diamond" :
2561 "cant.apply.diamond.1";
2562 return diags.create(dkind, log.currentSource(), pos, key,
2563 diags.fragment("diamond", site.tsym), details);
2564 }
2565 };
2566 sym = accessMethod(sym, pos, site, names.init, true, argtypes, typeargtypes);
2567 env.info.pendingResolutionPhase = currentResolutionContext.step;
2568 }
2569 }
2570 return sym;
2571 }});
2572 }
2574 /** This method scans all the constructor symbol in a given class scope -
2575 * assuming that the original scope contains a constructor of the kind:
2576 * {@code Foo(X x, Y y)}, where X,Y are class type-variables declared in Foo,
2577 * a method check is executed against the modified constructor type:
2578 * {@code <X,Y>Foo<X,Y>(X x, Y y)}. This is crucial in order to enable diamond
2579 * inference. The inferred return type of the synthetic constructor IS
2580 * the inferred type for the diamond operator.
2581 */
2582 private Symbol findDiamond(Env<AttrContext> env,
2583 Type site,
2584 List<Type> argtypes,
2585 List<Type> typeargtypes,
2586 boolean allowBoxing,
2587 boolean useVarargs) {
2588 Symbol bestSoFar = methodNotFound;
2589 for (Scope.Entry e = site.tsym.members().lookup(names.init);
2590 e.scope != null;
2591 e = e.next()) {
2592 final Symbol sym = e.sym;
2593 //- System.out.println(" e " + e.sym);
2594 if (sym.kind == MTH &&
2595 (sym.flags_field & SYNTHETIC) == 0) {
2596 List<Type> oldParams = e.sym.type.hasTag(FORALL) ?
2597 ((ForAll)sym.type).tvars :
2598 List.<Type>nil();
2599 Type constrType = new ForAll(site.tsym.type.getTypeArguments().appendList(oldParams),
2600 types.createMethodTypeWithReturn(sym.type.asMethodType(), site));
2601 MethodSymbol newConstr = new MethodSymbol(sym.flags(), names.init, constrType, site.tsym) {
2602 @Override
2603 public Symbol baseSymbol() {
2604 return sym;
2605 }
2606 };
2607 bestSoFar = selectBest(env, site, argtypes, typeargtypes,
2608 newConstr,
2609 bestSoFar,
2610 allowBoxing,
2611 useVarargs,
2612 false);
2613 }
2614 }
2615 return bestSoFar;
2616 }
2620 /** Resolve operator.
2621 * @param pos The position to use for error reporting.
2622 * @param optag The tag of the operation tree.
2623 * @param env The environment current at the operation.
2624 * @param argtypes The types of the operands.
2625 */
2626 Symbol resolveOperator(DiagnosticPosition pos, JCTree.Tag optag,
2627 Env<AttrContext> env, List<Type> argtypes) {
2628 MethodResolutionContext prevResolutionContext = currentResolutionContext;
2629 try {
2630 currentResolutionContext = new MethodResolutionContext();
2631 Name name = treeinfo.operatorName(optag);
2632 return lookupMethod(env, pos, syms.predefClass, currentResolutionContext,
2633 new BasicLookupHelper(name, syms.predefClass.type, argtypes, null, BOX) {
2634 @Override
2635 Symbol doLookup(Env<AttrContext> env, MethodResolutionPhase phase) {
2636 return findMethod(env, site, name, argtypes, typeargtypes,
2637 phase.isBoxingRequired(),
2638 phase.isVarargsRequired(), true);
2639 }
2640 @Override
2641 Symbol access(Env<AttrContext> env, DiagnosticPosition pos, Symbol location, Symbol sym) {
2642 return accessMethod(sym, pos, env.enclClass.sym.type, name,
2643 false, argtypes, null);
2644 }
2645 });
2646 } finally {
2647 currentResolutionContext = prevResolutionContext;
2648 }
2649 }
2651 /** Resolve operator.
2652 * @param pos The position to use for error reporting.
2653 * @param optag The tag of the operation tree.
2654 * @param env The environment current at the operation.
2655 * @param arg The type of the operand.
2656 */
2657 Symbol resolveUnaryOperator(DiagnosticPosition pos, JCTree.Tag optag, Env<AttrContext> env, Type arg) {
2658 return resolveOperator(pos, optag, env, List.of(arg));
2659 }
2661 /** Resolve binary operator.
2662 * @param pos The position to use for error reporting.
2663 * @param optag The tag of the operation tree.
2664 * @param env The environment current at the operation.
2665 * @param left The types of the left operand.
2666 * @param right The types of the right operand.
2667 */
2668 Symbol resolveBinaryOperator(DiagnosticPosition pos,
2669 JCTree.Tag optag,
2670 Env<AttrContext> env,
2671 Type left,
2672 Type right) {
2673 return resolveOperator(pos, optag, env, List.of(left, right));
2674 }
2676 /**
2677 * Resolution of member references is typically done as a single
2678 * overload resolution step, where the argument types A are inferred from
2679 * the target functional descriptor.
2680 *
2681 * If the member reference is a method reference with a type qualifier,
2682 * a two-step lookup process is performed. The first step uses the
2683 * expected argument list A, while the second step discards the first
2684 * type from A (which is treated as a receiver type).
2685 *
2686 * There are two cases in which inference is performed: (i) if the member
2687 * reference is a constructor reference and the qualifier type is raw - in
2688 * which case diamond inference is used to infer a parameterization for the
2689 * type qualifier; (ii) if the member reference is an unbound reference
2690 * where the type qualifier is raw - in that case, during the unbound lookup
2691 * the receiver argument type is used to infer an instantiation for the raw
2692 * qualifier type.
2693 *
2694 * When a multi-step resolution process is exploited, it is an error
2695 * if two candidates are found (ambiguity).
2696 *
2697 * This routine returns a pair (T,S), where S is the member reference symbol,
2698 * and T is the type of the class in which S is defined. This is necessary as
2699 * the type T might be dynamically inferred (i.e. if constructor reference
2700 * has a raw qualifier).
2701 */
2702 Pair<Symbol, ReferenceLookupHelper> resolveMemberReference(DiagnosticPosition pos,
2703 Env<AttrContext> env,
2704 JCMemberReference referenceTree,
2705 Type site,
2706 Name name, List<Type> argtypes,
2707 List<Type> typeargtypes,
2708 boolean boxingAllowed,
2709 MethodCheck methodCheck,
2710 InferenceContext inferenceContext) {
2711 MethodResolutionPhase maxPhase = boxingAllowed ? VARARITY : BASIC;
2713 if (site.hasTag(TYPEVAR)) {
2714 return resolveMemberReference(pos, env, referenceTree, site.getUpperBound(),
2715 name, argtypes, typeargtypes, boxingAllowed, methodCheck, inferenceContext);
2716 }
2718 site = types.capture(site);
2720 ReferenceLookupHelper boundLookupHelper;
2721 if (!name.equals(names.init)) {
2722 //method reference
2723 boundLookupHelper =
2724 new MethodReferenceLookupHelper(referenceTree, name, site, argtypes, typeargtypes, maxPhase);
2725 } else if (site.hasTag(ARRAY)) {
2726 //array constructor reference
2727 boundLookupHelper =
2728 new ArrayConstructorReferenceLookupHelper(referenceTree, site, argtypes, typeargtypes, maxPhase);
2729 } else {
2730 //class constructor reference
2731 boundLookupHelper =
2732 new ConstructorReferenceLookupHelper(referenceTree, site, argtypes, typeargtypes, maxPhase);
2733 }
2735 //step 1 - bound lookup
2736 Env<AttrContext> boundEnv = env.dup(env.tree, env.info.dup());
2737 Symbol boundSym = lookupMethod(boundEnv, env.tree.pos(), site.tsym, methodCheck, boundLookupHelper);
2739 //step 2 - unbound lookup
2740 ReferenceLookupHelper unboundLookupHelper = boundLookupHelper.unboundLookup(inferenceContext);
2741 Env<AttrContext> unboundEnv = env.dup(env.tree, env.info.dup());
2742 Symbol unboundSym = lookupMethod(unboundEnv, env.tree.pos(), site.tsym, methodCheck, unboundLookupHelper);
2744 //merge results
2745 Pair<Symbol, ReferenceLookupHelper> res;
2746 Symbol bestSym = choose(boundSym, unboundSym);
2747 res = new Pair<Symbol, ReferenceLookupHelper>(bestSym,
2748 bestSym == unboundSym ? unboundLookupHelper : boundLookupHelper);
2749 env.info.pendingResolutionPhase = bestSym == unboundSym ?
2750 unboundEnv.info.pendingResolutionPhase :
2751 boundEnv.info.pendingResolutionPhase;
2753 return res;
2754 }
2755 //where
2756 private Symbol choose(Symbol s1, Symbol s2) {
2757 if (lookupSuccess(s1) && lookupSuccess(s2)) {
2758 return ambiguityError(s1, s2);
2759 } else if (lookupSuccess(s1) ||
2760 (canIgnore(s2) && !canIgnore(s1))) {
2761 return s1;
2762 } else if (lookupSuccess(s2) ||
2763 (canIgnore(s1) && !canIgnore(s2))) {
2764 return s2;
2765 } else {
2766 return s1;
2767 }
2768 }
2770 private boolean lookupSuccess(Symbol s) {
2771 return s.kind == MTH || s.kind == AMBIGUOUS;
2772 }
2774 private boolean canIgnore(Symbol s) {
2775 switch (s.kind) {
2776 case ABSENT_MTH:
2777 return true;
2778 case WRONG_MTH:
2779 InapplicableSymbolError errSym =
2780 (InapplicableSymbolError)s;
2781 return new Template(MethodCheckDiag.ARITY_MISMATCH.regex())
2782 .matches(errSym.errCandidate().snd);
2783 case WRONG_MTHS:
2784 InapplicableSymbolsError errSyms =
2785 (InapplicableSymbolsError)s;
2786 return errSyms.filterCandidates(errSyms.mapCandidates()).isEmpty();
2787 default:
2788 return false;
2789 }
2790 }
2792 /**
2793 * Helper for defining custom method-like lookup logic; a lookup helper
2794 * provides hooks for (i) the actual lookup logic and (ii) accessing the
2795 * lookup result (this step might result in compiler diagnostics to be generated)
2796 */
2797 abstract class LookupHelper {
2799 /** name of the symbol to lookup */
2800 Name name;
2802 /** location in which the lookup takes place */
2803 Type site;
2805 /** actual types used during the lookup */
2806 List<Type> argtypes;
2808 /** type arguments used during the lookup */
2809 List<Type> typeargtypes;
2811 /** Max overload resolution phase handled by this helper */
2812 MethodResolutionPhase maxPhase;
2814 LookupHelper(Name name, Type site, List<Type> argtypes, List<Type> typeargtypes, MethodResolutionPhase maxPhase) {
2815 this.name = name;
2816 this.site = site;
2817 this.argtypes = argtypes;
2818 this.typeargtypes = typeargtypes;
2819 this.maxPhase = maxPhase;
2820 }
2822 /**
2823 * Should lookup stop at given phase with given result
2824 */
2825 protected boolean shouldStop(Symbol sym, MethodResolutionPhase phase) {
2826 return phase.ordinal() > maxPhase.ordinal() ||
2827 sym.kind < ERRONEOUS || sym.kind == AMBIGUOUS;
2828 }
2830 /**
2831 * Search for a symbol under a given overload resolution phase - this method
2832 * is usually called several times, once per each overload resolution phase
2833 */
2834 abstract Symbol lookup(Env<AttrContext> env, MethodResolutionPhase phase);
2836 /**
2837 * Dump overload resolution info
2838 */
2839 void debug(DiagnosticPosition pos, Symbol sym) {
2840 //do nothing
2841 }
2843 /**
2844 * Validate the result of the lookup
2845 */
2846 abstract Symbol access(Env<AttrContext> env, DiagnosticPosition pos, Symbol location, Symbol sym);
2847 }
2849 abstract class BasicLookupHelper extends LookupHelper {
2851 BasicLookupHelper(Name name, Type site, List<Type> argtypes, List<Type> typeargtypes) {
2852 this(name, site, argtypes, typeargtypes, MethodResolutionPhase.VARARITY);
2853 }
2855 BasicLookupHelper(Name name, Type site, List<Type> argtypes, List<Type> typeargtypes, MethodResolutionPhase maxPhase) {
2856 super(name, site, argtypes, typeargtypes, maxPhase);
2857 }
2859 @Override
2860 final Symbol lookup(Env<AttrContext> env, MethodResolutionPhase phase) {
2861 Symbol sym = doLookup(env, phase);
2862 if (sym.kind == AMBIGUOUS) {
2863 AmbiguityError a_err = (AmbiguityError)sym;
2864 sym = a_err.mergeAbstracts(site);
2865 }
2866 return sym;
2867 }
2869 abstract Symbol doLookup(Env<AttrContext> env, MethodResolutionPhase phase);
2871 @Override
2872 Symbol access(Env<AttrContext> env, DiagnosticPosition pos, Symbol location, Symbol sym) {
2873 if (sym.kind >= AMBIGUOUS) {
2874 //if nothing is found return the 'first' error
2875 sym = accessMethod(sym, pos, location, site, name, true, argtypes, typeargtypes);
2876 }
2877 return sym;
2878 }
2880 @Override
2881 void debug(DiagnosticPosition pos, Symbol sym) {
2882 reportVerboseResolutionDiagnostic(pos, name, site, argtypes, typeargtypes, sym);
2883 }
2884 }
2886 /**
2887 * Helper class for member reference lookup. A reference lookup helper
2888 * defines the basic logic for member reference lookup; a method gives
2889 * access to an 'unbound' helper used to perform an unbound member
2890 * reference lookup.
2891 */
2892 abstract class ReferenceLookupHelper extends LookupHelper {
2894 /** The member reference tree */
2895 JCMemberReference referenceTree;
2897 ReferenceLookupHelper(JCMemberReference referenceTree, Name name, Type site,
2898 List<Type> argtypes, List<Type> typeargtypes, MethodResolutionPhase maxPhase) {
2899 super(name, site, argtypes, typeargtypes, maxPhase);
2900 this.referenceTree = referenceTree;
2902 }
2904 /**
2905 * Returns an unbound version of this lookup helper. By default, this
2906 * method returns an dummy lookup helper.
2907 */
2908 ReferenceLookupHelper unboundLookup(InferenceContext inferenceContext) {
2909 //dummy loopkup helper that always return 'methodNotFound'
2910 return new ReferenceLookupHelper(referenceTree, name, site, argtypes, typeargtypes, maxPhase) {
2911 @Override
2912 ReferenceLookupHelper unboundLookup(InferenceContext inferenceContext) {
2913 return this;
2914 }
2915 @Override
2916 Symbol lookup(Env<AttrContext> env, MethodResolutionPhase phase) {
2917 return methodNotFound;
2918 }
2919 @Override
2920 ReferenceKind referenceKind(Symbol sym) {
2921 Assert.error();
2922 return null;
2923 }
2924 };
2925 }
2927 /**
2928 * Get the kind of the member reference
2929 */
2930 abstract JCMemberReference.ReferenceKind referenceKind(Symbol sym);
2932 Symbol access(Env<AttrContext> env, DiagnosticPosition pos, Symbol location, Symbol sym) {
2933 if (sym.kind == AMBIGUOUS) {
2934 AmbiguityError a_err = (AmbiguityError)sym;
2935 sym = a_err.mergeAbstracts(site);
2936 }
2937 //skip error reporting
2938 return sym;
2939 }
2940 }
2942 /**
2943 * Helper class for method reference lookup. The lookup logic is based
2944 * upon Resolve.findMethod; in certain cases, this helper class has a
2945 * corresponding unbound helper class (see UnboundMethodReferenceLookupHelper).
2946 * In such cases, non-static lookup results are thrown away.
2947 */
2948 class MethodReferenceLookupHelper extends ReferenceLookupHelper {
2950 MethodReferenceLookupHelper(JCMemberReference referenceTree, Name name, Type site,
2951 List<Type> argtypes, List<Type> typeargtypes, MethodResolutionPhase maxPhase) {
2952 super(referenceTree, name, site, argtypes, typeargtypes, maxPhase);
2953 }
2955 @Override
2956 final Symbol lookup(Env<AttrContext> env, MethodResolutionPhase phase) {
2957 return findMethod(env, site, name, argtypes, typeargtypes,
2958 phase.isBoxingRequired(), phase.isVarargsRequired(), syms.operatorNames.contains(name));
2959 }
2961 @Override
2962 ReferenceLookupHelper unboundLookup(InferenceContext inferenceContext) {
2963 if (TreeInfo.isStaticSelector(referenceTree.expr, names) &&
2964 argtypes.nonEmpty() &&
2965 (argtypes.head.hasTag(NONE) ||
2966 types.isSubtypeUnchecked(inferenceContext.asFree(argtypes.head), site))) {
2967 return new UnboundMethodReferenceLookupHelper(referenceTree, name,
2968 site, argtypes, typeargtypes, maxPhase);
2969 } else {
2970 return super.unboundLookup(inferenceContext);
2971 }
2972 }
2974 @Override
2975 ReferenceKind referenceKind(Symbol sym) {
2976 if (sym.isStatic()) {
2977 return ReferenceKind.STATIC;
2978 } else {
2979 Name selName = TreeInfo.name(referenceTree.getQualifierExpression());
2980 return selName != null && selName == names._super ?
2981 ReferenceKind.SUPER :
2982 ReferenceKind.BOUND;
2983 }
2984 }
2985 }
2987 /**
2988 * Helper class for unbound method reference lookup. Essentially the same
2989 * as the basic method reference lookup helper; main difference is that static
2990 * lookup results are thrown away. If qualifier type is raw, an attempt to
2991 * infer a parameterized type is made using the first actual argument (that
2992 * would otherwise be ignored during the lookup).
2993 */
2994 class UnboundMethodReferenceLookupHelper extends MethodReferenceLookupHelper {
2996 UnboundMethodReferenceLookupHelper(JCMemberReference referenceTree, Name name, Type site,
2997 List<Type> argtypes, List<Type> typeargtypes, MethodResolutionPhase maxPhase) {
2998 super(referenceTree, name, site, argtypes.tail, typeargtypes, maxPhase);
2999 if (site.isRaw() && !argtypes.head.hasTag(NONE)) {
3000 Type asSuperSite = types.asSuper(argtypes.head, site.tsym);
3001 this.site = asSuperSite;
3002 }
3003 }
3005 @Override
3006 ReferenceLookupHelper unboundLookup(InferenceContext inferenceContext) {
3007 return this;
3008 }
3010 @Override
3011 ReferenceKind referenceKind(Symbol sym) {
3012 return ReferenceKind.UNBOUND;
3013 }
3014 }
3016 /**
3017 * Helper class for array constructor lookup; an array constructor lookup
3018 * is simulated by looking up a method that returns the array type specified
3019 * as qualifier, and that accepts a single int parameter (size of the array).
3020 */
3021 class ArrayConstructorReferenceLookupHelper extends ReferenceLookupHelper {
3023 ArrayConstructorReferenceLookupHelper(JCMemberReference referenceTree, Type site, List<Type> argtypes,
3024 List<Type> typeargtypes, MethodResolutionPhase maxPhase) {
3025 super(referenceTree, names.init, site, argtypes, typeargtypes, maxPhase);
3026 }
3028 @Override
3029 protected Symbol lookup(Env<AttrContext> env, MethodResolutionPhase phase) {
3030 Scope sc = new Scope(syms.arrayClass);
3031 MethodSymbol arrayConstr = new MethodSymbol(PUBLIC, name, null, site.tsym);
3032 arrayConstr.type = new MethodType(List.<Type>of(syms.intType), site, List.<Type>nil(), syms.methodClass);
3033 sc.enter(arrayConstr);
3034 return findMethodInScope(env, site, name, argtypes, typeargtypes, sc, methodNotFound, phase.isBoxingRequired(), phase.isVarargsRequired(), false, false);
3035 }
3037 @Override
3038 ReferenceKind referenceKind(Symbol sym) {
3039 return ReferenceKind.ARRAY_CTOR;
3040 }
3041 }
3043 /**
3044 * Helper class for constructor reference lookup. The lookup logic is based
3045 * upon either Resolve.findMethod or Resolve.findDiamond - depending on
3046 * whether the constructor reference needs diamond inference (this is the case
3047 * if the qualifier type is raw). A special erroneous symbol is returned
3048 * if the lookup returns the constructor of an inner class and there's no
3049 * enclosing instance in scope.
3050 */
3051 class ConstructorReferenceLookupHelper extends ReferenceLookupHelper {
3053 boolean needsInference;
3055 ConstructorReferenceLookupHelper(JCMemberReference referenceTree, Type site, List<Type> argtypes,
3056 List<Type> typeargtypes, MethodResolutionPhase maxPhase) {
3057 super(referenceTree, names.init, site, argtypes, typeargtypes, maxPhase);
3058 if (site.isRaw()) {
3059 this.site = new ClassType(site.getEnclosingType(), site.tsym.type.getTypeArguments(), site.tsym);
3060 needsInference = true;
3061 }
3062 }
3064 @Override
3065 protected Symbol lookup(Env<AttrContext> env, MethodResolutionPhase phase) {
3066 Symbol sym = needsInference ?
3067 findDiamond(env, site, argtypes, typeargtypes, phase.isBoxingRequired(), phase.isVarargsRequired()) :
3068 findMethod(env, site, name, argtypes, typeargtypes,
3069 phase.isBoxingRequired(), phase.isVarargsRequired(), syms.operatorNames.contains(name));
3070 return sym.kind != MTH ||
3071 site.getEnclosingType().hasTag(NONE) ||
3072 hasEnclosingInstance(env, site) ?
3073 sym : new InvalidSymbolError(Kinds.MISSING_ENCL, sym, null) {
3074 @Override
3075 JCDiagnostic getDiagnostic(DiagnosticType dkind, DiagnosticPosition pos, Symbol location, Type site, Name name, List<Type> argtypes, List<Type> typeargtypes) {
3076 return diags.create(dkind, log.currentSource(), pos,
3077 "cant.access.inner.cls.constr", site.tsym.name, argtypes, site.getEnclosingType());
3078 }
3079 };
3080 }
3082 @Override
3083 ReferenceKind referenceKind(Symbol sym) {
3084 return site.getEnclosingType().hasTag(NONE) ?
3085 ReferenceKind.TOPLEVEL : ReferenceKind.IMPLICIT_INNER;
3086 }
3087 }
3089 /**
3090 * Main overload resolution routine. On each overload resolution step, a
3091 * lookup helper class is used to perform the method/constructor lookup;
3092 * at the end of the lookup, the helper is used to validate the results
3093 * (this last step might trigger overload resolution diagnostics).
3094 */
3095 Symbol lookupMethod(Env<AttrContext> env, DiagnosticPosition pos, Symbol location, MethodCheck methodCheck, LookupHelper lookupHelper) {
3096 MethodResolutionContext resolveContext = new MethodResolutionContext();
3097 resolveContext.methodCheck = methodCheck;
3098 return lookupMethod(env, pos, location, resolveContext, lookupHelper);
3099 }
3101 Symbol lookupMethod(Env<AttrContext> env, DiagnosticPosition pos, Symbol location,
3102 MethodResolutionContext resolveContext, LookupHelper lookupHelper) {
3103 MethodResolutionContext prevResolutionContext = currentResolutionContext;
3104 try {
3105 Symbol bestSoFar = methodNotFound;
3106 currentResolutionContext = resolveContext;
3107 for (MethodResolutionPhase phase : methodResolutionSteps) {
3108 if (!phase.isApplicable(boxingEnabled, varargsEnabled) ||
3109 lookupHelper.shouldStop(bestSoFar, phase)) break;
3110 MethodResolutionPhase prevPhase = currentResolutionContext.step;
3111 Symbol prevBest = bestSoFar;
3112 currentResolutionContext.step = phase;
3113 Symbol sym = lookupHelper.lookup(env, phase);
3114 lookupHelper.debug(pos, sym);
3115 bestSoFar = phase.mergeResults(bestSoFar, sym);
3116 env.info.pendingResolutionPhase = (prevBest == bestSoFar) ? prevPhase : phase;
3117 }
3118 return lookupHelper.access(env, pos, location, bestSoFar);
3119 } finally {
3120 currentResolutionContext = prevResolutionContext;
3121 }
3122 }
3124 /**
3125 * Resolve `c.name' where name == this or name == super.
3126 * @param pos The position to use for error reporting.
3127 * @param env The environment current at the expression.
3128 * @param c The qualifier.
3129 * @param name The identifier's name.
3130 */
3131 Symbol resolveSelf(DiagnosticPosition pos,
3132 Env<AttrContext> env,
3133 TypeSymbol c,
3134 Name name) {
3135 Env<AttrContext> env1 = env;
3136 boolean staticOnly = false;
3137 while (env1.outer != null) {
3138 if (isStatic(env1)) staticOnly = true;
3139 if (env1.enclClass.sym == c) {
3140 Symbol sym = env1.info.scope.lookup(name).sym;
3141 if (sym != null) {
3142 if (staticOnly) sym = new StaticError(sym);
3143 return accessBase(sym, pos, env.enclClass.sym.type,
3144 name, true);
3145 }
3146 }
3147 if ((env1.enclClass.sym.flags() & STATIC) != 0) staticOnly = true;
3148 env1 = env1.outer;
3149 }
3150 if (allowDefaultMethods && c.isInterface() &&
3151 name == names._super && !isStatic(env) &&
3152 types.isDirectSuperInterface(c, env.enclClass.sym)) {
3153 //this might be a default super call if one of the superinterfaces is 'c'
3154 for (Type t : pruneInterfaces(env.enclClass.type)) {
3155 if (t.tsym == c) {
3156 env.info.defaultSuperCallSite = t;
3157 return new VarSymbol(0, names._super,
3158 types.asSuper(env.enclClass.type, c), env.enclClass.sym);
3159 }
3160 }
3161 //find a direct superinterface that is a subtype of 'c'
3162 for (Type i : types.interfaces(env.enclClass.type)) {
3163 if (i.tsym.isSubClass(c, types) && i.tsym != c) {
3164 log.error(pos, "illegal.default.super.call", c,
3165 diags.fragment("redundant.supertype", c, i));
3166 return syms.errSymbol;
3167 }
3168 }
3169 Assert.error();
3170 }
3171 log.error(pos, "not.encl.class", c);
3172 return syms.errSymbol;
3173 }
3174 //where
3175 private List<Type> pruneInterfaces(Type t) {
3176 ListBuffer<Type> result = ListBuffer.lb();
3177 for (Type t1 : types.interfaces(t)) {
3178 boolean shouldAdd = true;
3179 for (Type t2 : types.interfaces(t)) {
3180 if (t1 != t2 && types.isSubtypeNoCapture(t2, t1)) {
3181 shouldAdd = false;
3182 }
3183 }
3184 if (shouldAdd) {
3185 result.append(t1);
3186 }
3187 }
3188 return result.toList();
3189 }
3192 /**
3193 * Resolve `c.this' for an enclosing class c that contains the
3194 * named member.
3195 * @param pos The position to use for error reporting.
3196 * @param env The environment current at the expression.
3197 * @param member The member that must be contained in the result.
3198 */
3199 Symbol resolveSelfContaining(DiagnosticPosition pos,
3200 Env<AttrContext> env,
3201 Symbol member,
3202 boolean isSuperCall) {
3203 Symbol sym = resolveSelfContainingInternal(env, member, isSuperCall);
3204 if (sym == null) {
3205 log.error(pos, "encl.class.required", member);
3206 return syms.errSymbol;
3207 } else {
3208 return accessBase(sym, pos, env.enclClass.sym.type, sym.name, true);
3209 }
3210 }
3212 boolean hasEnclosingInstance(Env<AttrContext> env, Type type) {
3213 Symbol encl = resolveSelfContainingInternal(env, type.tsym, false);
3214 return encl != null && encl.kind < ERRONEOUS;
3215 }
3217 private Symbol resolveSelfContainingInternal(Env<AttrContext> env,
3218 Symbol member,
3219 boolean isSuperCall) {
3220 Name name = names._this;
3221 Env<AttrContext> env1 = isSuperCall ? env.outer : env;
3222 boolean staticOnly = false;
3223 if (env1 != null) {
3224 while (env1 != null && env1.outer != null) {
3225 if (isStatic(env1)) staticOnly = true;
3226 if (env1.enclClass.sym.isSubClass(member.owner, types)) {
3227 Symbol sym = env1.info.scope.lookup(name).sym;
3228 if (sym != null) {
3229 if (staticOnly) sym = new StaticError(sym);
3230 return sym;
3231 }
3232 }
3233 if ((env1.enclClass.sym.flags() & STATIC) != 0)
3234 staticOnly = true;
3235 env1 = env1.outer;
3236 }
3237 }
3238 return null;
3239 }
3241 /**
3242 * Resolve an appropriate implicit this instance for t's container.
3243 * JLS 8.8.5.1 and 15.9.2
3244 */
3245 Type resolveImplicitThis(DiagnosticPosition pos, Env<AttrContext> env, Type t) {
3246 return resolveImplicitThis(pos, env, t, false);
3247 }
3249 Type resolveImplicitThis(DiagnosticPosition pos, Env<AttrContext> env, Type t, boolean isSuperCall) {
3250 Type thisType = (((t.tsym.owner.kind & (MTH|VAR)) != 0)
3251 ? resolveSelf(pos, env, t.getEnclosingType().tsym, names._this)
3252 : resolveSelfContaining(pos, env, t.tsym, isSuperCall)).type;
3253 if (env.info.isSelfCall && thisType.tsym == env.enclClass.sym)
3254 log.error(pos, "cant.ref.before.ctor.called", "this");
3255 return thisType;
3256 }
3258 /* ***************************************************************************
3259 * ResolveError classes, indicating error situations when accessing symbols
3260 ****************************************************************************/
3262 //used by TransTypes when checking target type of synthetic cast
3263 public void logAccessErrorInternal(Env<AttrContext> env, JCTree tree, Type type) {
3264 AccessError error = new AccessError(env, env.enclClass.type, type.tsym);
3265 logResolveError(error, tree.pos(), env.enclClass.sym, env.enclClass.type, null, null, null);
3266 }
3267 //where
3268 private void logResolveError(ResolveError error,
3269 DiagnosticPosition pos,
3270 Symbol location,
3271 Type site,
3272 Name name,
3273 List<Type> argtypes,
3274 List<Type> typeargtypes) {
3275 JCDiagnostic d = error.getDiagnostic(JCDiagnostic.DiagnosticType.ERROR,
3276 pos, location, site, name, argtypes, typeargtypes);
3277 if (d != null) {
3278 d.setFlag(DiagnosticFlag.RESOLVE_ERROR);
3279 log.report(d);
3280 }
3281 }
3283 private final LocalizedString noArgs = new LocalizedString("compiler.misc.no.args");
3285 public Object methodArguments(List<Type> argtypes) {
3286 if (argtypes == null || argtypes.isEmpty()) {
3287 return noArgs;
3288 } else {
3289 ListBuffer<Object> diagArgs = ListBuffer.lb();
3290 for (Type t : argtypes) {
3291 if (t.hasTag(DEFERRED)) {
3292 diagArgs.append(((DeferredAttr.DeferredType)t).tree);
3293 } else {
3294 diagArgs.append(t);
3295 }
3296 }
3297 return diagArgs;
3298 }
3299 }
3301 /**
3302 * Root class for resolution errors. Subclass of ResolveError
3303 * represent a different kinds of resolution error - as such they must
3304 * specify how they map into concrete compiler diagnostics.
3305 */
3306 abstract class ResolveError extends Symbol {
3308 /** The name of the kind of error, for debugging only. */
3309 final String debugName;
3311 ResolveError(int kind, String debugName) {
3312 super(kind, 0, null, null, null);
3313 this.debugName = debugName;
3314 }
3316 @Override
3317 public <R, P> R accept(ElementVisitor<R, P> v, P p) {
3318 throw new AssertionError();
3319 }
3321 @Override
3322 public String toString() {
3323 return debugName;
3324 }
3326 @Override
3327 public boolean exists() {
3328 return false;
3329 }
3331 /**
3332 * Create an external representation for this erroneous symbol to be
3333 * used during attribution - by default this returns the symbol of a
3334 * brand new error type which stores the original type found
3335 * during resolution.
3336 *
3337 * @param name the name used during resolution
3338 * @param location the location from which the symbol is accessed
3339 */
3340 protected Symbol access(Name name, TypeSymbol location) {
3341 return types.createErrorType(name, location, syms.errSymbol.type).tsym;
3342 }
3344 /**
3345 * Create a diagnostic representing this resolution error.
3346 *
3347 * @param dkind The kind of the diagnostic to be created (e.g error).
3348 * @param pos The position to be used for error reporting.
3349 * @param site The original type from where the selection took place.
3350 * @param name The name of the symbol to be resolved.
3351 * @param argtypes The invocation's value arguments,
3352 * if we looked for a method.
3353 * @param typeargtypes The invocation's type arguments,
3354 * if we looked for a method.
3355 */
3356 abstract JCDiagnostic getDiagnostic(JCDiagnostic.DiagnosticType dkind,
3357 DiagnosticPosition pos,
3358 Symbol location,
3359 Type site,
3360 Name name,
3361 List<Type> argtypes,
3362 List<Type> typeargtypes);
3363 }
3365 /**
3366 * This class is the root class of all resolution errors caused by
3367 * an invalid symbol being found during resolution.
3368 */
3369 abstract class InvalidSymbolError extends ResolveError {
3371 /** The invalid symbol found during resolution */
3372 Symbol sym;
3374 InvalidSymbolError(int kind, Symbol sym, String debugName) {
3375 super(kind, debugName);
3376 this.sym = sym;
3377 }
3379 @Override
3380 public boolean exists() {
3381 return true;
3382 }
3384 @Override
3385 public String toString() {
3386 return super.toString() + " wrongSym=" + sym;
3387 }
3389 @Override
3390 public Symbol access(Name name, TypeSymbol location) {
3391 if ((sym.kind & ERRONEOUS) == 0 && (sym.kind & TYP) != 0)
3392 return types.createErrorType(name, location, sym.type).tsym;
3393 else
3394 return sym;
3395 }
3396 }
3398 /**
3399 * InvalidSymbolError error class indicating that a symbol matching a
3400 * given name does not exists in a given site.
3401 */
3402 class SymbolNotFoundError extends ResolveError {
3404 SymbolNotFoundError(int kind) {
3405 super(kind, "symbol not found error");
3406 }
3408 @Override
3409 JCDiagnostic getDiagnostic(JCDiagnostic.DiagnosticType dkind,
3410 DiagnosticPosition pos,
3411 Symbol location,
3412 Type site,
3413 Name name,
3414 List<Type> argtypes,
3415 List<Type> typeargtypes) {
3416 argtypes = argtypes == null ? List.<Type>nil() : argtypes;
3417 typeargtypes = typeargtypes == null ? List.<Type>nil() : typeargtypes;
3418 if (name == names.error)
3419 return null;
3421 if (syms.operatorNames.contains(name)) {
3422 boolean isUnaryOp = argtypes.size() == 1;
3423 String key = argtypes.size() == 1 ?
3424 "operator.cant.be.applied" :
3425 "operator.cant.be.applied.1";
3426 Type first = argtypes.head;
3427 Type second = !isUnaryOp ? argtypes.tail.head : null;
3428 return diags.create(dkind, log.currentSource(), pos,
3429 key, name, first, second);
3430 }
3431 boolean hasLocation = false;
3432 if (location == null) {
3433 location = site.tsym;
3434 }
3435 if (!location.name.isEmpty()) {
3436 if (location.kind == PCK && !site.tsym.exists()) {
3437 return diags.create(dkind, log.currentSource(), pos,
3438 "doesnt.exist", location);
3439 }
3440 hasLocation = !location.name.equals(names._this) &&
3441 !location.name.equals(names._super);
3442 }
3443 boolean isConstructor = kind == ABSENT_MTH && name == names.init;
3444 KindName kindname = isConstructor ? KindName.CONSTRUCTOR : absentKind(kind);
3445 Name idname = isConstructor ? site.tsym.name : name;
3446 String errKey = getErrorKey(kindname, typeargtypes.nonEmpty(), hasLocation);
3447 if (hasLocation) {
3448 return diags.create(dkind, log.currentSource(), pos,
3449 errKey, kindname, idname, //symbol kindname, name
3450 typeargtypes, args(argtypes), //type parameters and arguments (if any)
3451 getLocationDiag(location, site)); //location kindname, type
3452 }
3453 else {
3454 return diags.create(dkind, log.currentSource(), pos,
3455 errKey, kindname, idname, //symbol kindname, name
3456 typeargtypes, args(argtypes)); //type parameters and arguments (if any)
3457 }
3458 }
3459 //where
3460 private Object args(List<Type> args) {
3461 return args.isEmpty() ? args : methodArguments(args);
3462 }
3464 private String getErrorKey(KindName kindname, boolean hasTypeArgs, boolean hasLocation) {
3465 String key = "cant.resolve";
3466 String suffix = hasLocation ? ".location" : "";
3467 switch (kindname) {
3468 case METHOD:
3469 case CONSTRUCTOR: {
3470 suffix += ".args";
3471 suffix += hasTypeArgs ? ".params" : "";
3472 }
3473 }
3474 return key + suffix;
3475 }
3476 private JCDiagnostic getLocationDiag(Symbol location, Type site) {
3477 if (location.kind == VAR) {
3478 return diags.fragment("location.1",
3479 kindName(location),
3480 location,
3481 location.type);
3482 } else {
3483 return diags.fragment("location",
3484 typeKindName(site),
3485 site,
3486 null);
3487 }
3488 }
3489 }
3491 /**
3492 * InvalidSymbolError error class indicating that a given symbol
3493 * (either a method, a constructor or an operand) is not applicable
3494 * given an actual arguments/type argument list.
3495 */
3496 class InapplicableSymbolError extends ResolveError {
3498 protected MethodResolutionContext resolveContext;
3500 InapplicableSymbolError(MethodResolutionContext context) {
3501 this(WRONG_MTH, "inapplicable symbol error", context);
3502 }
3504 protected InapplicableSymbolError(int kind, String debugName, MethodResolutionContext context) {
3505 super(kind, debugName);
3506 this.resolveContext = context;
3507 }
3509 @Override
3510 public String toString() {
3511 return super.toString();
3512 }
3514 @Override
3515 public boolean exists() {
3516 return true;
3517 }
3519 @Override
3520 JCDiagnostic getDiagnostic(JCDiagnostic.DiagnosticType dkind,
3521 DiagnosticPosition pos,
3522 Symbol location,
3523 Type site,
3524 Name name,
3525 List<Type> argtypes,
3526 List<Type> typeargtypes) {
3527 if (name == names.error)
3528 return null;
3530 if (syms.operatorNames.contains(name)) {
3531 boolean isUnaryOp = argtypes.size() == 1;
3532 String key = argtypes.size() == 1 ?
3533 "operator.cant.be.applied" :
3534 "operator.cant.be.applied.1";
3535 Type first = argtypes.head;
3536 Type second = !isUnaryOp ? argtypes.tail.head : null;
3537 return diags.create(dkind, log.currentSource(), pos,
3538 key, name, first, second);
3539 }
3540 else {
3541 Pair<Symbol, JCDiagnostic> c = errCandidate();
3542 if (compactMethodDiags) {
3543 for (Map.Entry<Template, DiagnosticRewriter> _entry :
3544 MethodResolutionDiagHelper.rewriters.entrySet()) {
3545 if (_entry.getKey().matches(c.snd)) {
3546 JCDiagnostic simpleDiag =
3547 _entry.getValue().rewriteDiagnostic(diags, pos,
3548 log.currentSource(), dkind, c.snd);
3549 simpleDiag.setFlag(DiagnosticFlag.COMPRESSED);
3550 return simpleDiag;
3551 }
3552 }
3553 }
3554 Symbol ws = c.fst.asMemberOf(site, types);
3555 return diags.create(dkind, log.currentSource(), pos,
3556 "cant.apply.symbol",
3557 kindName(ws),
3558 ws.name == names.init ? ws.owner.name : ws.name,
3559 methodArguments(ws.type.getParameterTypes()),
3560 methodArguments(argtypes),
3561 kindName(ws.owner),
3562 ws.owner.type,
3563 c.snd);
3564 }
3565 }
3567 @Override
3568 public Symbol access(Name name, TypeSymbol location) {
3569 return types.createErrorType(name, location, syms.errSymbol.type).tsym;
3570 }
3572 protected Pair<Symbol, JCDiagnostic> errCandidate() {
3573 Candidate bestSoFar = null;
3574 for (Candidate c : resolveContext.candidates) {
3575 if (c.isApplicable()) continue;
3576 bestSoFar = c;
3577 }
3578 Assert.checkNonNull(bestSoFar);
3579 return new Pair<Symbol, JCDiagnostic>(bestSoFar.sym, bestSoFar.details);
3580 }
3581 }
3583 /**
3584 * ResolveError error class indicating that a set of symbols
3585 * (either methods, constructors or operands) is not applicable
3586 * given an actual arguments/type argument list.
3587 */
3588 class InapplicableSymbolsError extends InapplicableSymbolError {
3590 InapplicableSymbolsError(MethodResolutionContext context) {
3591 super(WRONG_MTHS, "inapplicable symbols", context);
3592 }
3594 @Override
3595 JCDiagnostic getDiagnostic(JCDiagnostic.DiagnosticType dkind,
3596 DiagnosticPosition pos,
3597 Symbol location,
3598 Type site,
3599 Name name,
3600 List<Type> argtypes,
3601 List<Type> typeargtypes) {
3602 Map<Symbol, JCDiagnostic> candidatesMap = mapCandidates();
3603 Map<Symbol, JCDiagnostic> filteredCandidates = compactMethodDiags ?
3604 filterCandidates(candidatesMap) :
3605 mapCandidates();
3606 if (filteredCandidates.isEmpty()) {
3607 filteredCandidates = candidatesMap;
3608 }
3609 boolean truncatedDiag = candidatesMap.size() != filteredCandidates.size();
3610 if (filteredCandidates.size() > 1) {
3611 JCDiagnostic err = diags.create(dkind,
3612 null,
3613 truncatedDiag ?
3614 EnumSet.of(DiagnosticFlag.COMPRESSED) :
3615 EnumSet.noneOf(DiagnosticFlag.class),
3616 log.currentSource(),
3617 pos,
3618 "cant.apply.symbols",
3619 name == names.init ? KindName.CONSTRUCTOR : absentKind(kind),
3620 name == names.init ? site.tsym.name : name,
3621 methodArguments(argtypes));
3622 return new JCDiagnostic.MultilineDiagnostic(err, candidateDetails(filteredCandidates, site));
3623 } else if (filteredCandidates.size() == 1) {
3624 Map.Entry<Symbol, JCDiagnostic> _e =
3625 filteredCandidates.entrySet().iterator().next();
3626 final Pair<Symbol, JCDiagnostic> p = new Pair<Symbol, JCDiagnostic>(_e.getKey(), _e.getValue());
3627 JCDiagnostic d = new InapplicableSymbolError(resolveContext) {
3628 @Override
3629 protected Pair<Symbol, JCDiagnostic> errCandidate() {
3630 return p;
3631 }
3632 }.getDiagnostic(dkind, pos,
3633 location, site, name, argtypes, typeargtypes);
3634 if (truncatedDiag) {
3635 d.setFlag(DiagnosticFlag.COMPRESSED);
3636 }
3637 return d;
3638 } else {
3639 return new SymbolNotFoundError(ABSENT_MTH).getDiagnostic(dkind, pos,
3640 location, site, name, argtypes, typeargtypes);
3641 }
3642 }
3643 //where
3644 private Map<Symbol, JCDiagnostic> mapCandidates() {
3645 Map<Symbol, JCDiagnostic> candidates = new LinkedHashMap<Symbol, JCDiagnostic>();
3646 for (Candidate c : resolveContext.candidates) {
3647 if (c.isApplicable()) continue;
3648 candidates.put(c.sym, c.details);
3649 }
3650 return candidates;
3651 }
3653 Map<Symbol, JCDiagnostic> filterCandidates(Map<Symbol, JCDiagnostic> candidatesMap) {
3654 Map<Symbol, JCDiagnostic> candidates = new LinkedHashMap<Symbol, JCDiagnostic>();
3655 for (Map.Entry<Symbol, JCDiagnostic> _entry : candidatesMap.entrySet()) {
3656 JCDiagnostic d = _entry.getValue();
3657 if (!new Template(MethodCheckDiag.ARITY_MISMATCH.regex()).matches(d)) {
3658 candidates.put(_entry.getKey(), d);
3659 }
3660 }
3661 return candidates;
3662 }
3664 private List<JCDiagnostic> candidateDetails(Map<Symbol, JCDiagnostic> candidatesMap, Type site) {
3665 List<JCDiagnostic> details = List.nil();
3666 for (Map.Entry<Symbol, JCDiagnostic> _entry : candidatesMap.entrySet()) {
3667 Symbol sym = _entry.getKey();
3668 JCDiagnostic detailDiag = diags.fragment("inapplicable.method",
3669 Kinds.kindName(sym),
3670 sym.location(site, types),
3671 sym.asMemberOf(site, types),
3672 _entry.getValue());
3673 details = details.prepend(detailDiag);
3674 }
3675 //typically members are visited in reverse order (see Scope)
3676 //so we need to reverse the candidate list so that candidates
3677 //conform to source order
3678 return details;
3679 }
3680 }
3682 /**
3683 * An InvalidSymbolError error class indicating that a symbol is not
3684 * accessible from a given site
3685 */
3686 class AccessError extends InvalidSymbolError {
3688 private Env<AttrContext> env;
3689 private Type site;
3691 AccessError(Symbol sym) {
3692 this(null, null, sym);
3693 }
3695 AccessError(Env<AttrContext> env, Type site, Symbol sym) {
3696 super(HIDDEN, sym, "access error");
3697 this.env = env;
3698 this.site = site;
3699 if (debugResolve)
3700 log.error("proc.messager", sym + " @ " + site + " is inaccessible.");
3701 }
3703 @Override
3704 public boolean exists() {
3705 return false;
3706 }
3708 @Override
3709 JCDiagnostic getDiagnostic(JCDiagnostic.DiagnosticType dkind,
3710 DiagnosticPosition pos,
3711 Symbol location,
3712 Type site,
3713 Name name,
3714 List<Type> argtypes,
3715 List<Type> typeargtypes) {
3716 if (sym.owner.type.hasTag(ERROR))
3717 return null;
3719 if (sym.name == names.init && sym.owner != site.tsym) {
3720 return new SymbolNotFoundError(ABSENT_MTH).getDiagnostic(dkind,
3721 pos, location, site, name, argtypes, typeargtypes);
3722 }
3723 else if ((sym.flags() & PUBLIC) != 0
3724 || (env != null && this.site != null
3725 && !isAccessible(env, this.site))) {
3726 return diags.create(dkind, log.currentSource(),
3727 pos, "not.def.access.class.intf.cant.access",
3728 sym, sym.location());
3729 }
3730 else if ((sym.flags() & (PRIVATE | PROTECTED)) != 0) {
3731 return diags.create(dkind, log.currentSource(),
3732 pos, "report.access", sym,
3733 asFlagSet(sym.flags() & (PRIVATE | PROTECTED)),
3734 sym.location());
3735 }
3736 else {
3737 return diags.create(dkind, log.currentSource(),
3738 pos, "not.def.public.cant.access", sym, sym.location());
3739 }
3740 }
3741 }
3743 /**
3744 * InvalidSymbolError error class indicating that an instance member
3745 * has erroneously been accessed from a static context.
3746 */
3747 class StaticError extends InvalidSymbolError {
3749 StaticError(Symbol sym) {
3750 super(STATICERR, sym, "static error");
3751 }
3753 @Override
3754 JCDiagnostic getDiagnostic(JCDiagnostic.DiagnosticType dkind,
3755 DiagnosticPosition pos,
3756 Symbol location,
3757 Type site,
3758 Name name,
3759 List<Type> argtypes,
3760 List<Type> typeargtypes) {
3761 Symbol errSym = ((sym.kind == TYP && sym.type.hasTag(CLASS))
3762 ? types.erasure(sym.type).tsym
3763 : sym);
3764 return diags.create(dkind, log.currentSource(), pos,
3765 "non-static.cant.be.ref", kindName(sym), errSym);
3766 }
3767 }
3769 /**
3770 * InvalidSymbolError error class indicating that a pair of symbols
3771 * (either methods, constructors or operands) are ambiguous
3772 * given an actual arguments/type argument list.
3773 */
3774 class AmbiguityError extends ResolveError {
3776 /** The other maximally specific symbol */
3777 List<Symbol> ambiguousSyms = List.nil();
3779 @Override
3780 public boolean exists() {
3781 return true;
3782 }
3784 AmbiguityError(Symbol sym1, Symbol sym2) {
3785 super(AMBIGUOUS, "ambiguity error");
3786 ambiguousSyms = flatten(sym2).appendList(flatten(sym1));
3787 }
3789 private List<Symbol> flatten(Symbol sym) {
3790 if (sym.kind == AMBIGUOUS) {
3791 return ((AmbiguityError)sym).ambiguousSyms;
3792 } else {
3793 return List.of(sym);
3794 }
3795 }
3797 AmbiguityError addAmbiguousSymbol(Symbol s) {
3798 ambiguousSyms = ambiguousSyms.prepend(s);
3799 return this;
3800 }
3802 @Override
3803 JCDiagnostic getDiagnostic(JCDiagnostic.DiagnosticType dkind,
3804 DiagnosticPosition pos,
3805 Symbol location,
3806 Type site,
3807 Name name,
3808 List<Type> argtypes,
3809 List<Type> typeargtypes) {
3810 List<Symbol> diagSyms = ambiguousSyms.reverse();
3811 Symbol s1 = diagSyms.head;
3812 Symbol s2 = diagSyms.tail.head;
3813 Name sname = s1.name;
3814 if (sname == names.init) sname = s1.owner.name;
3815 return diags.create(dkind, log.currentSource(),
3816 pos, "ref.ambiguous", sname,
3817 kindName(s1),
3818 s1,
3819 s1.location(site, types),
3820 kindName(s2),
3821 s2,
3822 s2.location(site, types));
3823 }
3825 /**
3826 * If multiple applicable methods are found during overload and none of them
3827 * is more specific than the others, attempt to merge their signatures.
3828 */
3829 Symbol mergeAbstracts(Type site) {
3830 List<Symbol> ambiguousInOrder = ambiguousSyms.reverse();
3831 for (Symbol s : ambiguousInOrder) {
3832 Type mt = types.memberType(site, s);
3833 boolean found = true;
3834 List<Type> allThrown = mt.getThrownTypes();
3835 for (Symbol s2 : ambiguousInOrder) {
3836 Type mt2 = types.memberType(site, s2);
3837 if ((s2.flags() & ABSTRACT) == 0 ||
3838 !types.overrideEquivalent(mt, mt2) ||
3839 !types.isSameTypes(s.erasure(types).getParameterTypes(),
3840 s2.erasure(types).getParameterTypes())) {
3841 //ambiguity cannot be resolved
3842 return this;
3843 }
3844 Type mst = mostSpecificReturnType(mt, mt2);
3845 if (mst == null || mst != mt) {
3846 found = false;
3847 break;
3848 }
3849 allThrown = chk.intersect(allThrown, mt2.getThrownTypes());
3850 }
3851 if (found) {
3852 //all ambiguous methods were abstract and one method had
3853 //most specific return type then others
3854 return (allThrown == mt.getThrownTypes()) ?
3855 s : new MethodSymbol(
3856 s.flags(),
3857 s.name,
3858 types.createMethodTypeWithThrown(mt, allThrown),
3859 s.owner);
3860 }
3861 }
3862 return this;
3863 }
3865 @Override
3866 protected Symbol access(Name name, TypeSymbol location) {
3867 Symbol firstAmbiguity = ambiguousSyms.last();
3868 return firstAmbiguity.kind == TYP ?
3869 types.createErrorType(name, location, firstAmbiguity.type).tsym :
3870 firstAmbiguity;
3871 }
3872 }
3874 class BadVarargsMethod extends ResolveError {
3876 ResolveError delegatedError;
3878 BadVarargsMethod(ResolveError delegatedError) {
3879 super(delegatedError.kind, "badVarargs");
3880 this.delegatedError = delegatedError;
3881 }
3883 @Override
3884 public Symbol baseSymbol() {
3885 return delegatedError.baseSymbol();
3886 }
3888 @Override
3889 protected Symbol access(Name name, TypeSymbol location) {
3890 return delegatedError.access(name, location);
3891 }
3893 @Override
3894 public boolean exists() {
3895 return true;
3896 }
3898 @Override
3899 JCDiagnostic getDiagnostic(DiagnosticType dkind, DiagnosticPosition pos, Symbol location, Type site, Name name, List<Type> argtypes, List<Type> typeargtypes) {
3900 return delegatedError.getDiagnostic(dkind, pos, location, site, name, argtypes, typeargtypes);
3901 }
3902 }
3904 /**
3905 * Helper class for method resolution diagnostic simplification.
3906 * Certain resolution diagnostic are rewritten as simpler diagnostic
3907 * where the enclosing resolution diagnostic (i.e. 'inapplicable method')
3908 * is stripped away, as it doesn't carry additional info. The logic
3909 * for matching a given diagnostic is given in terms of a template
3910 * hierarchy: a diagnostic template can be specified programmatically,
3911 * so that only certain diagnostics are matched. Each templete is then
3912 * associated with a rewriter object that carries out the task of rewtiting
3913 * the diagnostic to a simpler one.
3914 */
3915 static class MethodResolutionDiagHelper {
3917 /**
3918 * A diagnostic rewriter transforms a method resolution diagnostic
3919 * into a simpler one
3920 */
3921 interface DiagnosticRewriter {
3922 JCDiagnostic rewriteDiagnostic(JCDiagnostic.Factory diags,
3923 DiagnosticPosition preferedPos, DiagnosticSource preferredSource,
3924 DiagnosticType preferredKind, JCDiagnostic d);
3925 }
3927 /**
3928 * A diagnostic template is made up of two ingredients: (i) a regular
3929 * expression for matching a diagnostic key and (ii) a list of sub-templates
3930 * for matching diagnostic arguments.
3931 */
3932 static class Template {
3934 /** regex used to match diag key */
3935 String regex;
3937 /** templates used to match diagnostic args */
3938 Template[] subTemplates;
3940 Template(String key, Template... subTemplates) {
3941 this.regex = key;
3942 this.subTemplates = subTemplates;
3943 }
3945 /**
3946 * Returns true if the regex matches the diagnostic key and if
3947 * all diagnostic arguments are matches by corresponding sub-templates.
3948 */
3949 boolean matches(Object o) {
3950 JCDiagnostic d = (JCDiagnostic)o;
3951 Object[] args = d.getArgs();
3952 if (!d.getCode().matches(regex) ||
3953 subTemplates.length != d.getArgs().length) {
3954 return false;
3955 }
3956 for (int i = 0; i < args.length ; i++) {
3957 if (!subTemplates[i].matches(args[i])) {
3958 return false;
3959 }
3960 }
3961 return true;
3962 }
3963 }
3965 /** a dummy template that match any diagnostic argument */
3966 static final Template skip = new Template("") {
3967 @Override
3968 boolean matches(Object d) {
3969 return true;
3970 }
3971 };
3973 /** rewriter map used for method resolution simplification */
3974 static final Map<Template, DiagnosticRewriter> rewriters =
3975 new LinkedHashMap<Template, DiagnosticRewriter>();
3977 static {
3978 String argMismatchRegex = MethodCheckDiag.ARG_MISMATCH.regex();
3979 rewriters.put(new Template(argMismatchRegex, skip),
3980 new DiagnosticRewriter() {
3981 @Override
3982 public JCDiagnostic rewriteDiagnostic(JCDiagnostic.Factory diags,
3983 DiagnosticPosition preferedPos, DiagnosticSource preferredSource,
3984 DiagnosticType preferredKind, JCDiagnostic d) {
3985 JCDiagnostic cause = (JCDiagnostic)d.getArgs()[0];
3986 return diags.create(preferredKind, preferredSource, d.getDiagnosticPosition(),
3987 "prob.found.req", cause);
3988 }
3989 });
3990 }
3991 }
3993 enum MethodResolutionPhase {
3994 BASIC(false, false),
3995 BOX(true, false),
3996 VARARITY(true, true) {
3997 @Override
3998 public Symbol mergeResults(Symbol bestSoFar, Symbol sym) {
3999 switch (sym.kind) {
4000 case WRONG_MTH:
4001 return (bestSoFar.kind == WRONG_MTH || bestSoFar.kind == WRONG_MTHS) ?
4002 bestSoFar :
4003 sym;
4004 case ABSENT_MTH:
4005 return bestSoFar;
4006 default:
4007 return sym;
4008 }
4009 }
4010 };
4012 final boolean isBoxingRequired;
4013 final boolean isVarargsRequired;
4015 MethodResolutionPhase(boolean isBoxingRequired, boolean isVarargsRequired) {
4016 this.isBoxingRequired = isBoxingRequired;
4017 this.isVarargsRequired = isVarargsRequired;
4018 }
4020 public boolean isBoxingRequired() {
4021 return isBoxingRequired;
4022 }
4024 public boolean isVarargsRequired() {
4025 return isVarargsRequired;
4026 }
4028 public boolean isApplicable(boolean boxingEnabled, boolean varargsEnabled) {
4029 return (varargsEnabled || !isVarargsRequired) &&
4030 (boxingEnabled || !isBoxingRequired);
4031 }
4033 public Symbol mergeResults(Symbol prev, Symbol sym) {
4034 return sym;
4035 }
4036 }
4038 final List<MethodResolutionPhase> methodResolutionSteps = List.of(BASIC, BOX, VARARITY);
4040 /**
4041 * A resolution context is used to keep track of intermediate results of
4042 * overload resolution, such as list of method that are not applicable
4043 * (used to generate more precise diagnostics) and so on. Resolution contexts
4044 * can be nested - this means that when each overload resolution routine should
4045 * work within the resolution context it created.
4046 */
4047 class MethodResolutionContext {
4049 private List<Candidate> candidates = List.nil();
4051 MethodResolutionPhase step = null;
4053 MethodCheck methodCheck = resolveMethodCheck;
4055 private boolean internalResolution = false;
4056 private DeferredAttr.AttrMode attrMode = DeferredAttr.AttrMode.SPECULATIVE;
4058 void addInapplicableCandidate(Symbol sym, JCDiagnostic details) {
4059 Candidate c = new Candidate(currentResolutionContext.step, sym, details, null);
4060 candidates = candidates.append(c);
4061 }
4063 void addApplicableCandidate(Symbol sym, Type mtype) {
4064 Candidate c = new Candidate(currentResolutionContext.step, sym, null, mtype);
4065 candidates = candidates.append(c);
4066 }
4068 DeferredAttrContext deferredAttrContext(Symbol sym, InferenceContext inferenceContext, ResultInfo pendingResult, Warner warn) {
4069 return deferredAttr.new DeferredAttrContext(attrMode, sym, step, inferenceContext, pendingResult != null ? pendingResult.checkContext.deferredAttrContext() : deferredAttr.emptyDeferredAttrContext, warn);
4070 }
4072 /**
4073 * This class represents an overload resolution candidate. There are two
4074 * kinds of candidates: applicable methods and inapplicable methods;
4075 * applicable methods have a pointer to the instantiated method type,
4076 * while inapplicable candidates contain further details about the
4077 * reason why the method has been considered inapplicable.
4078 */
4079 @SuppressWarnings("overrides")
4080 class Candidate {
4082 final MethodResolutionPhase step;
4083 final Symbol sym;
4084 final JCDiagnostic details;
4085 final Type mtype;
4087 private Candidate(MethodResolutionPhase step, Symbol sym, JCDiagnostic details, Type mtype) {
4088 this.step = step;
4089 this.sym = sym;
4090 this.details = details;
4091 this.mtype = mtype;
4092 }
4094 @Override
4095 public boolean equals(Object o) {
4096 if (o instanceof Candidate) {
4097 Symbol s1 = this.sym;
4098 Symbol s2 = ((Candidate)o).sym;
4099 if ((s1 != s2 &&
4100 (s1.overrides(s2, s1.owner.type.tsym, types, false) ||
4101 (s2.overrides(s1, s2.owner.type.tsym, types, false)))) ||
4102 ((s1.isConstructor() || s2.isConstructor()) && s1.owner != s2.owner))
4103 return true;
4104 }
4105 return false;
4106 }
4108 boolean isApplicable() {
4109 return mtype != null;
4110 }
4111 }
4113 DeferredAttr.AttrMode attrMode() {
4114 return attrMode;
4115 }
4117 boolean internal() {
4118 return internalResolution;
4119 }
4120 }
4122 MethodResolutionContext currentResolutionContext = null;
4123 }
