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src/share/classes/com/sun/tools/javac/comp/Resolve.java@f657d400c736
src/share/classes/com/sun/tools/javac/comp/Resolve.java
Thu, 15 Aug 2013 22:36:08 +0200
- author
- jlahoda
- date
- Thu, 15 Aug 2013 22:36:08 +0200
- changeset 1956
- f657d400c736
- parent 1945
- f7f271bd74a2
- child 1970
- 2068190f8ac2
- permissions
- -rw-r--r--
8022508: javac crashes if the generics arity of a base class is wrong
Reviewed-by: mcimadamore, vromero
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 currentResolutionContext.methodCheck.argumentsAcceptable(env, currentResolutionContext.deferredAttrContext(m, infer.emptyContext, resultInfo, warn),
572 argtypes, mt.getParameterTypes(), warn);
573 return mt;
574 }
576 Type checkMethod(Env<AttrContext> env,
577 Type site,
578 Symbol m,
579 ResultInfo resultInfo,
580 List<Type> argtypes,
581 List<Type> typeargtypes,
582 Warner warn) {
583 MethodResolutionContext prevContext = currentResolutionContext;
584 try {
585 currentResolutionContext = new MethodResolutionContext();
586 currentResolutionContext.attrMode = DeferredAttr.AttrMode.CHECK;
587 if (env.tree.hasTag(JCTree.Tag.REFERENCE)) {
588 //method/constructor references need special check class
589 //to handle inference variables in 'argtypes' (might happen
590 //during an unsticking round)
591 currentResolutionContext.methodCheck =
592 new MethodReferenceCheck(resultInfo.checkContext.inferenceContext());
593 }
594 MethodResolutionPhase step = currentResolutionContext.step = env.info.pendingResolutionPhase;
595 return rawInstantiate(env, site, m, resultInfo, argtypes, typeargtypes,
596 step.isBoxingRequired(), step.isVarargsRequired(), warn);
597 }
598 finally {
599 currentResolutionContext = prevContext;
600 }
601 }
603 /** Same but returns null instead throwing a NoInstanceException
604 */
605 Type instantiate(Env<AttrContext> env,
606 Type site,
607 Symbol m,
608 ResultInfo resultInfo,
609 List<Type> argtypes,
610 List<Type> typeargtypes,
611 boolean allowBoxing,
612 boolean useVarargs,
613 Warner warn) {
614 try {
615 return rawInstantiate(env, site, m, resultInfo, argtypes, typeargtypes,
616 allowBoxing, useVarargs, warn);
617 } catch (InapplicableMethodException ex) {
618 return null;
619 }
620 }
622 /**
623 * This interface defines an entry point that should be used to perform a
624 * method check. A method check usually consist in determining as to whether
625 * a set of types (actuals) is compatible with another set of types (formals).
626 * Since the notion of compatibility can vary depending on the circumstances,
627 * this interfaces allows to easily add new pluggable method check routines.
628 */
629 interface MethodCheck {
630 /**
631 * Main method check routine. A method check usually consist in determining
632 * as to whether a set of types (actuals) is compatible with another set of
633 * types (formals). If an incompatibility is found, an unchecked exception
634 * is assumed to be thrown.
635 */
636 void argumentsAcceptable(Env<AttrContext> env,
637 DeferredAttrContext deferredAttrContext,
638 List<Type> argtypes,
639 List<Type> formals,
640 Warner warn);
642 /**
643 * Retrieve the method check object that will be used during a
644 * most specific check.
645 */
646 MethodCheck mostSpecificCheck(List<Type> actuals, boolean strict);
647 }
649 /**
650 * Helper enum defining all method check diagnostics (used by resolveMethodCheck).
651 */
652 enum MethodCheckDiag {
653 /**
654 * Actuals and formals differs in length.
655 */
656 ARITY_MISMATCH("arg.length.mismatch", "infer.arg.length.mismatch"),
657 /**
658 * An actual is incompatible with a formal.
659 */
660 ARG_MISMATCH("no.conforming.assignment.exists", "infer.no.conforming.assignment.exists"),
661 /**
662 * An actual is incompatible with the varargs element type.
663 */
664 VARARG_MISMATCH("varargs.argument.mismatch", "infer.varargs.argument.mismatch"),
665 /**
666 * The varargs element type is inaccessible.
667 */
668 INACCESSIBLE_VARARGS("inaccessible.varargs.type", "inaccessible.varargs.type");
670 final String basicKey;
671 final String inferKey;
673 MethodCheckDiag(String basicKey, String inferKey) {
674 this.basicKey = basicKey;
675 this.inferKey = inferKey;
676 }
678 String regex() {
679 return String.format("([a-z]*\\.)*(%s|%s)", basicKey, inferKey);
680 }
681 }
683 /**
684 * Dummy method check object. All methods are deemed applicable, regardless
685 * of their formal parameter types.
686 */
687 MethodCheck nilMethodCheck = new MethodCheck() {
688 public void argumentsAcceptable(Env<AttrContext> env, DeferredAttrContext deferredAttrContext, List<Type> argtypes, List<Type> formals, Warner warn) {
689 //do nothing - method always applicable regardless of actuals
690 }
692 public MethodCheck mostSpecificCheck(List<Type> actuals, boolean strict) {
693 return this;
694 }
695 };
697 /**
698 * Base class for 'real' method checks. The class defines the logic for
699 * iterating through formals and actuals and provides and entry point
700 * that can be used by subclasses in order to define the actual check logic.
701 */
702 abstract class AbstractMethodCheck implements MethodCheck {
703 @Override
704 public void argumentsAcceptable(final Env<AttrContext> env,
705 DeferredAttrContext deferredAttrContext,
706 List<Type> argtypes,
707 List<Type> formals,
708 Warner warn) {
709 //should we expand formals?
710 boolean useVarargs = deferredAttrContext.phase.isVarargsRequired();
711 List<JCExpression> trees = TreeInfo.args(env.tree);
713 //inference context used during this method check
714 InferenceContext inferenceContext = deferredAttrContext.inferenceContext;
716 Type varargsFormal = useVarargs ? formals.last() : null;
718 if (varargsFormal == null &&
719 argtypes.size() != formals.size()) {
720 reportMC(env.tree, MethodCheckDiag.ARITY_MISMATCH, inferenceContext); // not enough args
721 }
723 while (argtypes.nonEmpty() && formals.head != varargsFormal) {
724 DiagnosticPosition pos = trees != null ? trees.head : null;
725 checkArg(pos, false, argtypes.head, formals.head, deferredAttrContext, warn);
726 argtypes = argtypes.tail;
727 formals = formals.tail;
728 trees = trees != null ? trees.tail : trees;
729 }
731 if (formals.head != varargsFormal) {
732 reportMC(env.tree, MethodCheckDiag.ARITY_MISMATCH, inferenceContext); // not enough args
733 }
735 if (useVarargs) {
736 //note: if applicability check is triggered by most specific test,
737 //the last argument of a varargs is _not_ an array type (see JLS 15.12.2.5)
738 final Type elt = types.elemtype(varargsFormal);
739 while (argtypes.nonEmpty()) {
740 DiagnosticPosition pos = trees != null ? trees.head : null;
741 checkArg(pos, true, argtypes.head, elt, deferredAttrContext, warn);
742 argtypes = argtypes.tail;
743 trees = trees != null ? trees.tail : trees;
744 }
745 }
746 }
748 /**
749 * Does the actual argument conforms to the corresponding formal?
750 */
751 abstract void checkArg(DiagnosticPosition pos, boolean varargs, Type actual, Type formal, DeferredAttrContext deferredAttrContext, Warner warn);
753 protected void reportMC(DiagnosticPosition pos, MethodCheckDiag diag, InferenceContext inferenceContext, Object... args) {
754 boolean inferDiag = inferenceContext != infer.emptyContext;
755 InapplicableMethodException ex = inferDiag ?
756 infer.inferenceException : inapplicableMethodException;
757 if (inferDiag && (!diag.inferKey.equals(diag.basicKey))) {
758 Object[] args2 = new Object[args.length + 1];
759 System.arraycopy(args, 0, args2, 1, args.length);
760 args2[0] = inferenceContext.inferenceVars();
761 args = args2;
762 }
763 String key = inferDiag ? diag.inferKey : diag.basicKey;
764 throw ex.setMessage(diags.create(DiagnosticType.FRAGMENT, log.currentSource(), pos, key, args));
765 }
767 public MethodCheck mostSpecificCheck(List<Type> actuals, boolean strict) {
768 return nilMethodCheck;
769 }
770 }
772 /**
773 * Arity-based method check. A method is applicable if the number of actuals
774 * supplied conforms to the method signature.
775 */
776 MethodCheck arityMethodCheck = new AbstractMethodCheck() {
777 @Override
778 void checkArg(DiagnosticPosition pos, boolean varargs, Type actual, Type formal, DeferredAttrContext deferredAttrContext, Warner warn) {
779 //do nothing - actual always compatible to formals
780 }
781 };
783 List<Type> dummyArgs(int length) {
784 ListBuffer<Type> buf = ListBuffer.lb();
785 for (int i = 0 ; i < length ; i++) {
786 buf.append(Type.noType);
787 }
788 return buf.toList();
789 }
791 /**
792 * Main method applicability routine. Given a list of actual types A,
793 * a list of formal types F, determines whether the types in A are
794 * compatible (by method invocation conversion) with the types in F.
795 *
796 * Since this routine is shared between overload resolution and method
797 * type-inference, a (possibly empty) inference context is used to convert
798 * formal types to the corresponding 'undet' form ahead of a compatibility
799 * check so that constraints can be propagated and collected.
800 *
801 * Moreover, if one or more types in A is a deferred type, this routine uses
802 * DeferredAttr in order to perform deferred attribution. If one or more actual
803 * deferred types are stuck, they are placed in a queue and revisited later
804 * after the remainder of the arguments have been seen. If this is not sufficient
805 * to 'unstuck' the argument, a cyclic inference error is called out.
806 *
807 * A method check handler (see above) is used in order to report errors.
808 */
809 MethodCheck resolveMethodCheck = new AbstractMethodCheck() {
811 @Override
812 void checkArg(DiagnosticPosition pos, boolean varargs, Type actual, Type formal, DeferredAttrContext deferredAttrContext, Warner warn) {
813 ResultInfo mresult = methodCheckResult(varargs, formal, deferredAttrContext, warn);
814 mresult.check(pos, actual);
815 }
817 @Override
818 public void argumentsAcceptable(final Env<AttrContext> env,
819 DeferredAttrContext deferredAttrContext,
820 List<Type> argtypes,
821 List<Type> formals,
822 Warner warn) {
823 super.argumentsAcceptable(env, deferredAttrContext, argtypes, formals, warn);
824 //should we expand formals?
825 if (deferredAttrContext.phase.isVarargsRequired()) {
826 //check varargs element type accessibility
827 varargsAccessible(env, types.elemtype(formals.last()),
828 deferredAttrContext.inferenceContext);
829 }
830 }
832 private void varargsAccessible(final Env<AttrContext> env, final Type t, final InferenceContext inferenceContext) {
833 if (inferenceContext.free(t)) {
834 inferenceContext.addFreeTypeListener(List.of(t), new FreeTypeListener() {
835 @Override
836 public void typesInferred(InferenceContext inferenceContext) {
837 varargsAccessible(env, inferenceContext.asInstType(t), inferenceContext);
838 }
839 });
840 } else {
841 if (!isAccessible(env, t)) {
842 Symbol location = env.enclClass.sym;
843 reportMC(env.tree, MethodCheckDiag.INACCESSIBLE_VARARGS, inferenceContext, t, Kinds.kindName(location), location);
844 }
845 }
846 }
848 private ResultInfo methodCheckResult(final boolean varargsCheck, Type to,
849 final DeferredAttr.DeferredAttrContext deferredAttrContext, Warner rsWarner) {
850 CheckContext checkContext = new MethodCheckContext(!deferredAttrContext.phase.isBoxingRequired(), deferredAttrContext, rsWarner) {
851 MethodCheckDiag methodDiag = varargsCheck ?
852 MethodCheckDiag.VARARG_MISMATCH : MethodCheckDiag.ARG_MISMATCH;
854 @Override
855 public void report(DiagnosticPosition pos, JCDiagnostic details) {
856 reportMC(pos, methodDiag, deferredAttrContext.inferenceContext, details);
857 }
858 };
859 return new MethodResultInfo(to, checkContext);
860 }
862 @Override
863 public MethodCheck mostSpecificCheck(List<Type> actuals, boolean strict) {
864 return new MostSpecificCheck(strict, actuals);
865 }
866 };
868 class MethodReferenceCheck extends AbstractMethodCheck {
870 InferenceContext pendingInferenceContext;
872 MethodReferenceCheck(InferenceContext pendingInferenceContext) {
873 this.pendingInferenceContext = pendingInferenceContext;
874 }
876 @Override
877 void checkArg(DiagnosticPosition pos, boolean varargs, Type actual, Type formal, DeferredAttrContext deferredAttrContext, Warner warn) {
878 ResultInfo mresult = methodCheckResult(varargs, formal, deferredAttrContext, warn);
879 mresult.check(pos, actual);
880 }
882 private ResultInfo methodCheckResult(final boolean varargsCheck, Type to,
883 final DeferredAttr.DeferredAttrContext deferredAttrContext, Warner rsWarner) {
884 CheckContext checkContext = new MethodCheckContext(!deferredAttrContext.phase.isBoxingRequired(), deferredAttrContext, rsWarner) {
885 MethodCheckDiag methodDiag = varargsCheck ?
886 MethodCheckDiag.VARARG_MISMATCH : MethodCheckDiag.ARG_MISMATCH;
888 @Override
889 public boolean compatible(Type found, Type req, Warner warn) {
890 found = pendingInferenceContext.asFree(found);
891 req = infer.returnConstraintTarget(found, req);
892 return super.compatible(found, req, warn);
893 }
895 @Override
896 public void report(DiagnosticPosition pos, JCDiagnostic details) {
897 reportMC(pos, methodDiag, deferredAttrContext.inferenceContext, details);
898 }
899 };
900 return new MethodResultInfo(to, checkContext);
901 }
903 @Override
904 public MethodCheck mostSpecificCheck(List<Type> actuals, boolean strict) {
905 return new MostSpecificCheck(strict, actuals);
906 }
907 };
909 /**
910 * Check context to be used during method applicability checks. A method check
911 * context might contain inference variables.
912 */
913 abstract class MethodCheckContext implements CheckContext {
915 boolean strict;
916 DeferredAttrContext deferredAttrContext;
917 Warner rsWarner;
919 public MethodCheckContext(boolean strict, DeferredAttrContext deferredAttrContext, Warner rsWarner) {
920 this.strict = strict;
921 this.deferredAttrContext = deferredAttrContext;
922 this.rsWarner = rsWarner;
923 }
925 public boolean compatible(Type found, Type req, Warner warn) {
926 return strict ?
927 types.isSubtypeUnchecked(found, deferredAttrContext.inferenceContext.asFree(req), warn) :
928 types.isConvertible(found, deferredAttrContext.inferenceContext.asFree(req), warn);
929 }
931 public void report(DiagnosticPosition pos, JCDiagnostic details) {
932 throw inapplicableMethodException.setMessage(details);
933 }
935 public Warner checkWarner(DiagnosticPosition pos, Type found, Type req) {
936 return rsWarner;
937 }
939 public InferenceContext inferenceContext() {
940 return deferredAttrContext.inferenceContext;
941 }
943 public DeferredAttrContext deferredAttrContext() {
944 return deferredAttrContext;
945 }
946 }
948 /**
949 * ResultInfo class to be used during method applicability checks. Check
950 * for deferred types goes through special path.
951 */
952 class MethodResultInfo extends ResultInfo {
954 public MethodResultInfo(Type pt, CheckContext checkContext) {
955 attr.super(VAL, pt, checkContext);
956 }
958 @Override
959 protected Type check(DiagnosticPosition pos, Type found) {
960 if (found.hasTag(DEFERRED)) {
961 DeferredType dt = (DeferredType)found;
962 return dt.check(this);
963 } else {
964 return super.check(pos, chk.checkNonVoid(pos, types.capture(U(found.baseType()))));
965 }
966 }
968 /**
969 * javac has a long-standing 'simplification' (see 6391995):
970 * given an actual argument type, the method check is performed
971 * on its upper bound. This leads to inconsistencies when an
972 * argument type is checked against itself. For example, given
973 * a type-variable T, it is not true that {@code U(T) <: T},
974 * so we need to guard against that.
975 */
976 private Type U(Type found) {
977 return found == pt ?
978 found : types.upperBound(found);
979 }
981 @Override
982 protected MethodResultInfo dup(Type newPt) {
983 return new MethodResultInfo(newPt, checkContext);
984 }
986 @Override
987 protected ResultInfo dup(CheckContext newContext) {
988 return new MethodResultInfo(pt, newContext);
989 }
990 }
992 /**
993 * Most specific method applicability routine. Given a list of actual types A,
994 * a list of formal types F1, and a list of formal types F2, the routine determines
995 * as to whether the types in F1 can be considered more specific than those in F2 w.r.t.
996 * argument types A.
997 */
998 class MostSpecificCheck implements MethodCheck {
1000 boolean strict;
1001 List<Type> actuals;
1003 MostSpecificCheck(boolean strict, List<Type> actuals) {
1004 this.strict = strict;
1005 this.actuals = actuals;
1006 }
1008 @Override
1009 public void argumentsAcceptable(final Env<AttrContext> env,
1010 DeferredAttrContext deferredAttrContext,
1011 List<Type> formals1,
1012 List<Type> formals2,
1013 Warner warn) {
1014 formals2 = adjustArgs(formals2, deferredAttrContext.msym, formals1.length(), deferredAttrContext.phase.isVarargsRequired());
1015 while (formals2.nonEmpty()) {
1016 ResultInfo mresult = methodCheckResult(formals2.head, deferredAttrContext, warn, actuals.head);
1017 mresult.check(null, formals1.head);
1018 formals1 = formals1.tail;
1019 formals2 = formals2.tail;
1020 actuals = actuals.isEmpty() ? actuals : actuals.tail;
1021 }
1022 }
1024 /**
1025 * Create a method check context to be used during the most specific applicability check
1026 */
1027 ResultInfo methodCheckResult(Type to, DeferredAttr.DeferredAttrContext deferredAttrContext,
1028 Warner rsWarner, Type actual) {
1029 return attr.new ResultInfo(Kinds.VAL, to,
1030 new MostSpecificCheckContext(strict, deferredAttrContext, rsWarner, actual));
1031 }
1033 /**
1034 * Subclass of method check context class that implements most specific
1035 * method conversion. If the actual type under analysis is a deferred type
1036 * a full blown structural analysis is carried out.
1037 */
1038 class MostSpecificCheckContext extends MethodCheckContext {
1040 Type actual;
1042 public MostSpecificCheckContext(boolean strict, DeferredAttrContext deferredAttrContext, Warner rsWarner, Type actual) {
1043 super(strict, deferredAttrContext, rsWarner);
1044 this.actual = actual;
1045 }
1047 public boolean compatible(Type found, Type req, Warner warn) {
1048 if (!allowStructuralMostSpecific || actual == null) {
1049 return super.compatible(found, req, warn);
1050 } else {
1051 switch (actual.getTag()) {
1052 case DEFERRED:
1053 DeferredType dt = (DeferredType) actual;
1054 DeferredType.SpeculativeCache.Entry e = dt.speculativeCache.get(deferredAttrContext.msym, deferredAttrContext.phase);
1055 return (e == null || e.speculativeTree == deferredAttr.stuckTree)
1056 ? false : mostSpecific(found, req, e.speculativeTree, warn);
1057 default:
1058 return standaloneMostSpecific(found, req, actual, warn);
1059 }
1060 }
1061 }
1063 private boolean mostSpecific(Type t, Type s, JCTree tree, Warner warn) {
1064 MostSpecificChecker msc = new MostSpecificChecker(t, s, warn);
1065 msc.scan(tree);
1066 return msc.result;
1067 }
1069 boolean polyMostSpecific(Type t1, Type t2, Warner warn) {
1070 return (!t1.isPrimitive() && t2.isPrimitive())
1071 ? true : super.compatible(t1, t2, warn);
1072 }
1074 boolean standaloneMostSpecific(Type t1, Type t2, Type exprType, Warner warn) {
1075 return (exprType.isPrimitive() == t1.isPrimitive()
1076 && exprType.isPrimitive() != t2.isPrimitive())
1077 ? true : super.compatible(t1, t2, warn);
1078 }
1080 /**
1081 * Structural checker for most specific.
1082 */
1083 class MostSpecificChecker extends DeferredAttr.PolyScanner {
1085 final Type t;
1086 final Type s;
1087 final Warner warn;
1088 boolean result;
1090 MostSpecificChecker(Type t, Type s, Warner warn) {
1091 this.t = t;
1092 this.s = s;
1093 this.warn = warn;
1094 result = true;
1095 }
1097 @Override
1098 void skip(JCTree tree) {
1099 result &= standaloneMostSpecific(t, s, tree.type, warn);
1100 }
1102 @Override
1103 public void visitConditional(JCConditional tree) {
1104 if (tree.polyKind == PolyKind.STANDALONE) {
1105 result &= standaloneMostSpecific(t, s, tree.type, warn);
1106 } else {
1107 super.visitConditional(tree);
1108 }
1109 }
1111 @Override
1112 public void visitApply(JCMethodInvocation tree) {
1113 result &= (tree.polyKind == PolyKind.STANDALONE)
1114 ? standaloneMostSpecific(t, s, tree.type, warn)
1115 : polyMostSpecific(t, s, warn);
1116 }
1118 @Override
1119 public void visitNewClass(JCNewClass tree) {
1120 result &= (tree.polyKind == PolyKind.STANDALONE)
1121 ? standaloneMostSpecific(t, s, tree.type, warn)
1122 : polyMostSpecific(t, s, warn);
1123 }
1125 @Override
1126 public void visitReference(JCMemberReference tree) {
1127 if (types.isFunctionalInterface(t.tsym) &&
1128 types.isFunctionalInterface(s.tsym) &&
1129 types.asSuper(t, s.tsym) == null &&
1130 types.asSuper(s, t.tsym) == null) {
1131 Type desc_t = types.findDescriptorType(t);
1132 Type desc_s = types.findDescriptorType(s);
1133 if (types.isSameTypes(desc_t.getParameterTypes(), desc_s.getParameterTypes())) {
1134 if (!desc_s.getReturnType().hasTag(VOID)) {
1135 //perform structural comparison
1136 Type ret_t = desc_t.getReturnType();
1137 Type ret_s = desc_s.getReturnType();
1138 result &= ((tree.refPolyKind == PolyKind.STANDALONE)
1139 ? standaloneMostSpecific(ret_t, ret_s, tree.sym.type.getReturnType(), warn)
1140 : polyMostSpecific(ret_t, ret_s, warn));
1141 } else {
1142 return;
1143 }
1144 } else {
1145 result &= false;
1146 }
1147 } else {
1148 result &= MostSpecificCheckContext.super.compatible(t, s, warn);
1149 }
1150 }
1152 @Override
1153 public void visitLambda(JCLambda tree) {
1154 if (types.isFunctionalInterface(t.tsym) &&
1155 types.isFunctionalInterface(s.tsym) &&
1156 types.asSuper(t, s.tsym) == null &&
1157 types.asSuper(s, t.tsym) == null) {
1158 Type desc_t = types.findDescriptorType(t);
1159 Type desc_s = types.findDescriptorType(s);
1160 if (tree.paramKind == JCLambda.ParameterKind.EXPLICIT
1161 || types.isSameTypes(desc_t.getParameterTypes(), desc_s.getParameterTypes())) {
1162 if (!desc_s.getReturnType().hasTag(VOID)) {
1163 //perform structural comparison
1164 Type ret_t = desc_t.getReturnType();
1165 Type ret_s = desc_s.getReturnType();
1166 scanLambdaBody(tree, ret_t, ret_s);
1167 } else {
1168 return;
1169 }
1170 } else {
1171 result &= false;
1172 }
1173 } else {
1174 result &= MostSpecificCheckContext.super.compatible(t, s, warn);
1175 }
1176 }
1177 //where
1179 void scanLambdaBody(JCLambda lambda, final Type t, final Type s) {
1180 if (lambda.getBodyKind() == JCTree.JCLambda.BodyKind.EXPRESSION) {
1181 result &= MostSpecificCheckContext.this.mostSpecific(t, s, lambda.body, warn);
1182 } else {
1183 DeferredAttr.LambdaReturnScanner lambdaScanner =
1184 new DeferredAttr.LambdaReturnScanner() {
1185 @Override
1186 public void visitReturn(JCReturn tree) {
1187 if (tree.expr != null) {
1188 result &= MostSpecificCheckContext.this.mostSpecific(t, s, tree.expr, warn);
1189 }
1190 }
1191 };
1192 lambdaScanner.scan(lambda.body);
1193 }
1194 }
1195 }
1196 }
1198 public MethodCheck mostSpecificCheck(List<Type> actuals, boolean strict) {
1199 Assert.error("Cannot get here!");
1200 return null;
1201 }
1202 }
1204 public static class InapplicableMethodException extends RuntimeException {
1205 private static final long serialVersionUID = 0;
1207 JCDiagnostic diagnostic;
1208 JCDiagnostic.Factory diags;
1210 InapplicableMethodException(JCDiagnostic.Factory diags) {
1211 this.diagnostic = null;
1212 this.diags = diags;
1213 }
1214 InapplicableMethodException setMessage() {
1215 return setMessage((JCDiagnostic)null);
1216 }
1217 InapplicableMethodException setMessage(String key) {
1218 return setMessage(key != null ? diags.fragment(key) : null);
1219 }
1220 InapplicableMethodException setMessage(String key, Object... args) {
1221 return setMessage(key != null ? diags.fragment(key, args) : null);
1222 }
1223 InapplicableMethodException setMessage(JCDiagnostic diag) {
1224 this.diagnostic = diag;
1225 return this;
1226 }
1228 public JCDiagnostic getDiagnostic() {
1229 return diagnostic;
1230 }
1231 }
1232 private final InapplicableMethodException inapplicableMethodException;
1234 /* ***************************************************************************
1235 * Symbol lookup
1236 * the following naming conventions for arguments are used
1237 *
1238 * env is the environment where the symbol was mentioned
1239 * site is the type of which the symbol is a member
1240 * name is the symbol's name
1241 * if no arguments are given
1242 * argtypes are the value arguments, if we search for a method
1243 *
1244 * If no symbol was found, a ResolveError detailing the problem is returned.
1245 ****************************************************************************/
1247 /** Find field. Synthetic fields are always skipped.
1248 * @param env The current environment.
1249 * @param site The original type from where the selection takes place.
1250 * @param name The name of the field.
1251 * @param c The class to search for the field. This is always
1252 * a superclass or implemented interface of site's class.
1253 */
1254 Symbol findField(Env<AttrContext> env,
1255 Type site,
1256 Name name,
1257 TypeSymbol c) {
1258 while (c.type.hasTag(TYPEVAR))
1259 c = c.type.getUpperBound().tsym;
1260 Symbol bestSoFar = varNotFound;
1261 Symbol sym;
1262 Scope.Entry e = c.members().lookup(name);
1263 while (e.scope != null) {
1264 if (e.sym.kind == VAR && (e.sym.flags_field & SYNTHETIC) == 0) {
1265 return isAccessible(env, site, e.sym)
1266 ? e.sym : new AccessError(env, site, e.sym);
1267 }
1268 e = e.next();
1269 }
1270 Type st = types.supertype(c.type);
1271 if (st != null && (st.hasTag(CLASS) || st.hasTag(TYPEVAR))) {
1272 sym = findField(env, site, name, st.tsym);
1273 if (sym.kind < bestSoFar.kind) bestSoFar = sym;
1274 }
1275 for (List<Type> l = types.interfaces(c.type);
1276 bestSoFar.kind != AMBIGUOUS && l.nonEmpty();
1277 l = l.tail) {
1278 sym = findField(env, site, name, l.head.tsym);
1279 if (bestSoFar.exists() && sym.exists() &&
1280 sym.owner != bestSoFar.owner)
1281 bestSoFar = new AmbiguityError(bestSoFar, sym);
1282 else if (sym.kind < bestSoFar.kind)
1283 bestSoFar = sym;
1284 }
1285 return bestSoFar;
1286 }
1288 /** Resolve a field identifier, throw a fatal error if not found.
1289 * @param pos The position to use for error reporting.
1290 * @param env The environment current at the method invocation.
1291 * @param site The type of the qualifying expression, in which
1292 * identifier is searched.
1293 * @param name The identifier's name.
1294 */
1295 public VarSymbol resolveInternalField(DiagnosticPosition pos, Env<AttrContext> env,
1296 Type site, Name name) {
1297 Symbol sym = findField(env, site, name, site.tsym);
1298 if (sym.kind == VAR) return (VarSymbol)sym;
1299 else throw new FatalError(
1300 diags.fragment("fatal.err.cant.locate.field",
1301 name));
1302 }
1304 /** Find unqualified variable or field with given name.
1305 * Synthetic fields always skipped.
1306 * @param env The current environment.
1307 * @param name The name of the variable or field.
1308 */
1309 Symbol findVar(Env<AttrContext> env, Name name) {
1310 Symbol bestSoFar = varNotFound;
1311 Symbol sym;
1312 Env<AttrContext> env1 = env;
1313 boolean staticOnly = false;
1314 while (env1.outer != null) {
1315 if (isStatic(env1)) staticOnly = true;
1316 Scope.Entry e = env1.info.scope.lookup(name);
1317 while (e.scope != null &&
1318 (e.sym.kind != VAR ||
1319 (e.sym.flags_field & SYNTHETIC) != 0))
1320 e = e.next();
1321 sym = (e.scope != null)
1322 ? e.sym
1323 : findField(
1324 env1, env1.enclClass.sym.type, name, env1.enclClass.sym);
1325 if (sym.exists()) {
1326 if (staticOnly &&
1327 sym.kind == VAR &&
1328 sym.owner.kind == TYP &&
1329 (sym.flags() & STATIC) == 0)
1330 return new StaticError(sym);
1331 else
1332 return sym;
1333 } else if (sym.kind < bestSoFar.kind) {
1334 bestSoFar = sym;
1335 }
1337 if ((env1.enclClass.sym.flags() & STATIC) != 0) staticOnly = true;
1338 env1 = env1.outer;
1339 }
1341 sym = findField(env, syms.predefClass.type, name, syms.predefClass);
1342 if (sym.exists())
1343 return sym;
1344 if (bestSoFar.exists())
1345 return bestSoFar;
1347 Symbol origin = null;
1348 for (Scope sc : new Scope[] { env.toplevel.namedImportScope, env.toplevel.starImportScope }) {
1349 Scope.Entry e = sc.lookup(name);
1350 for (; e.scope != null; e = e.next()) {
1351 sym = e.sym;
1352 if (sym.kind != VAR)
1353 continue;
1354 // invariant: sym.kind == VAR
1355 if (bestSoFar.kind < AMBIGUOUS && sym.owner != bestSoFar.owner)
1356 return new AmbiguityError(bestSoFar, sym);
1357 else if (bestSoFar.kind >= VAR) {
1358 origin = e.getOrigin().owner;
1359 bestSoFar = isAccessible(env, origin.type, sym)
1360 ? sym : new AccessError(env, origin.type, sym);
1361 }
1362 }
1363 if (bestSoFar.exists()) break;
1364 }
1365 if (bestSoFar.kind == VAR && bestSoFar.owner.type != origin.type)
1366 return bestSoFar.clone(origin);
1367 else
1368 return bestSoFar;
1369 }
1371 Warner noteWarner = new Warner();
1373 /** Select the best method for a call site among two choices.
1374 * @param env The current environment.
1375 * @param site The original type from where the
1376 * selection takes place.
1377 * @param argtypes The invocation's value arguments,
1378 * @param typeargtypes The invocation's type arguments,
1379 * @param sym Proposed new best match.
1380 * @param bestSoFar Previously found best match.
1381 * @param allowBoxing Allow boxing conversions of arguments.
1382 * @param useVarargs Box trailing arguments into an array for varargs.
1383 */
1384 @SuppressWarnings("fallthrough")
1385 Symbol selectBest(Env<AttrContext> env,
1386 Type site,
1387 List<Type> argtypes,
1388 List<Type> typeargtypes,
1389 Symbol sym,
1390 Symbol bestSoFar,
1391 boolean allowBoxing,
1392 boolean useVarargs,
1393 boolean operator) {
1394 if (sym.kind == ERR ||
1395 !sym.isInheritedIn(site.tsym, types)) {
1396 return bestSoFar;
1397 } else if (useVarargs && (sym.flags() & VARARGS) == 0) {
1398 return bestSoFar.kind >= ERRONEOUS ?
1399 new BadVarargsMethod((ResolveError)bestSoFar) :
1400 bestSoFar;
1401 }
1402 Assert.check(sym.kind < AMBIGUOUS);
1403 try {
1404 Type mt = rawInstantiate(env, site, sym, null, argtypes, typeargtypes,
1405 allowBoxing, useVarargs, types.noWarnings);
1406 if (!operator || verboseResolutionMode.contains(VerboseResolutionMode.PREDEF))
1407 currentResolutionContext.addApplicableCandidate(sym, mt);
1408 } catch (InapplicableMethodException ex) {
1409 if (!operator)
1410 currentResolutionContext.addInapplicableCandidate(sym, ex.getDiagnostic());
1411 switch (bestSoFar.kind) {
1412 case ABSENT_MTH:
1413 return new InapplicableSymbolError(currentResolutionContext);
1414 case WRONG_MTH:
1415 if (operator) return bestSoFar;
1416 bestSoFar = new InapplicableSymbolsError(currentResolutionContext);
1417 default:
1418 return bestSoFar;
1419 }
1420 }
1421 if (!isAccessible(env, site, sym)) {
1422 return (bestSoFar.kind == ABSENT_MTH)
1423 ? new AccessError(env, site, sym)
1424 : bestSoFar;
1425 }
1426 return (bestSoFar.kind > AMBIGUOUS)
1427 ? sym
1428 : mostSpecific(argtypes, sym, bestSoFar, env, site,
1429 allowBoxing && operator, useVarargs);
1430 }
1432 /* Return the most specific of the two methods for a call,
1433 * given that both are accessible and applicable.
1434 * @param m1 A new candidate for most specific.
1435 * @param m2 The previous most specific candidate.
1436 * @param env The current environment.
1437 * @param site The original type from where the selection
1438 * takes place.
1439 * @param allowBoxing Allow boxing conversions of arguments.
1440 * @param useVarargs Box trailing arguments into an array for varargs.
1441 */
1442 Symbol mostSpecific(List<Type> argtypes, Symbol m1,
1443 Symbol m2,
1444 Env<AttrContext> env,
1445 final Type site,
1446 boolean allowBoxing,
1447 boolean useVarargs) {
1448 switch (m2.kind) {
1449 case MTH:
1450 if (m1 == m2) return m1;
1451 boolean m1SignatureMoreSpecific =
1452 signatureMoreSpecific(argtypes, env, site, m1, m2, allowBoxing, useVarargs);
1453 boolean m2SignatureMoreSpecific =
1454 signatureMoreSpecific(argtypes, env, site, m2, m1, allowBoxing, useVarargs);
1455 if (m1SignatureMoreSpecific && m2SignatureMoreSpecific) {
1456 Type mt1 = types.memberType(site, m1);
1457 Type mt2 = types.memberType(site, m2);
1458 if (!types.overrideEquivalent(mt1, mt2))
1459 return ambiguityError(m1, m2);
1461 // same signature; select (a) the non-bridge method, or
1462 // (b) the one that overrides the other, or (c) the concrete
1463 // one, or (d) merge both abstract signatures
1464 if ((m1.flags() & BRIDGE) != (m2.flags() & BRIDGE))
1465 return ((m1.flags() & BRIDGE) != 0) ? m2 : m1;
1467 // if one overrides or hides the other, use it
1468 TypeSymbol m1Owner = (TypeSymbol)m1.owner;
1469 TypeSymbol m2Owner = (TypeSymbol)m2.owner;
1470 if (types.asSuper(m1Owner.type, m2Owner) != null &&
1471 ((m1.owner.flags_field & INTERFACE) == 0 ||
1472 (m2.owner.flags_field & INTERFACE) != 0) &&
1473 m1.overrides(m2, m1Owner, types, false))
1474 return m1;
1475 if (types.asSuper(m2Owner.type, m1Owner) != null &&
1476 ((m2.owner.flags_field & INTERFACE) == 0 ||
1477 (m1.owner.flags_field & INTERFACE) != 0) &&
1478 m2.overrides(m1, m2Owner, types, false))
1479 return m2;
1480 boolean m1Abstract = (m1.flags() & ABSTRACT) != 0;
1481 boolean m2Abstract = (m2.flags() & ABSTRACT) != 0;
1482 if (m1Abstract && !m2Abstract) return m2;
1483 if (m2Abstract && !m1Abstract) return m1;
1484 // both abstract or both concrete
1485 return ambiguityError(m1, m2);
1486 }
1487 if (m1SignatureMoreSpecific) return m1;
1488 if (m2SignatureMoreSpecific) return m2;
1489 return ambiguityError(m1, m2);
1490 case AMBIGUOUS:
1491 //check if m1 is more specific than all ambiguous methods in m2
1492 AmbiguityError e = (AmbiguityError)m2;
1493 for (Symbol s : e.ambiguousSyms) {
1494 if (mostSpecific(argtypes, m1, s, env, site, allowBoxing, useVarargs) != m1) {
1495 return e.addAmbiguousSymbol(m1);
1496 }
1497 }
1498 return m1;
1499 default:
1500 throw new AssertionError();
1501 }
1502 }
1503 //where
1504 private boolean signatureMoreSpecific(List<Type> actuals, Env<AttrContext> env, Type site, Symbol m1, Symbol m2, boolean allowBoxing, boolean useVarargs) {
1505 noteWarner.clear();
1506 int maxLength = Math.max(
1507 Math.max(m1.type.getParameterTypes().length(), actuals.length()),
1508 m2.type.getParameterTypes().length());
1509 MethodResolutionContext prevResolutionContext = currentResolutionContext;
1510 try {
1511 currentResolutionContext = new MethodResolutionContext();
1512 currentResolutionContext.step = prevResolutionContext.step;
1513 currentResolutionContext.methodCheck =
1514 prevResolutionContext.methodCheck.mostSpecificCheck(actuals, !allowBoxing);
1515 Type mst = instantiate(env, site, m2, null,
1516 adjustArgs(types.lowerBounds(types.memberType(site, m1).getParameterTypes()), m1, maxLength, useVarargs), null,
1517 allowBoxing, useVarargs, noteWarner);
1518 return mst != null &&
1519 !noteWarner.hasLint(Lint.LintCategory.UNCHECKED);
1520 } finally {
1521 currentResolutionContext = prevResolutionContext;
1522 }
1523 }
1524 private List<Type> adjustArgs(List<Type> args, Symbol msym, int length, boolean allowVarargs) {
1525 if ((msym.flags() & VARARGS) != 0 && allowVarargs) {
1526 Type varargsElem = types.elemtype(args.last());
1527 if (varargsElem == null) {
1528 Assert.error("Bad varargs = " + args.last() + " " + msym);
1529 }
1530 List<Type> newArgs = args.reverse().tail.prepend(varargsElem).reverse();
1531 while (newArgs.length() < length) {
1532 newArgs = newArgs.append(newArgs.last());
1533 }
1534 return newArgs;
1535 } else {
1536 return args;
1537 }
1538 }
1539 //where
1540 Type mostSpecificReturnType(Type mt1, Type mt2) {
1541 Type rt1 = mt1.getReturnType();
1542 Type rt2 = mt2.getReturnType();
1544 if (mt1.hasTag(FORALL) && mt2.hasTag(FORALL)) {
1545 //if both are generic methods, adjust return type ahead of subtyping check
1546 rt1 = types.subst(rt1, mt1.getTypeArguments(), mt2.getTypeArguments());
1547 }
1548 //first use subtyping, then return type substitutability
1549 if (types.isSubtype(rt1, rt2)) {
1550 return mt1;
1551 } else if (types.isSubtype(rt2, rt1)) {
1552 return mt2;
1553 } else if (types.returnTypeSubstitutable(mt1, mt2)) {
1554 return mt1;
1555 } else if (types.returnTypeSubstitutable(mt2, mt1)) {
1556 return mt2;
1557 } else {
1558 return null;
1559 }
1560 }
1561 //where
1562 Symbol ambiguityError(Symbol m1, Symbol m2) {
1563 if (((m1.flags() | m2.flags()) & CLASH) != 0) {
1564 return (m1.flags() & CLASH) == 0 ? m1 : m2;
1565 } else {
1566 return new AmbiguityError(m1, m2);
1567 }
1568 }
1570 Symbol findMethodInScope(Env<AttrContext> env,
1571 Type site,
1572 Name name,
1573 List<Type> argtypes,
1574 List<Type> typeargtypes,
1575 Scope sc,
1576 Symbol bestSoFar,
1577 boolean allowBoxing,
1578 boolean useVarargs,
1579 boolean operator,
1580 boolean abstractok) {
1581 for (Symbol s : sc.getElementsByName(name, new LookupFilter(abstractok))) {
1582 bestSoFar = selectBest(env, site, argtypes, typeargtypes, s,
1583 bestSoFar, allowBoxing, useVarargs, operator);
1584 }
1585 return bestSoFar;
1586 }
1587 //where
1588 class LookupFilter implements Filter<Symbol> {
1590 boolean abstractOk;
1592 LookupFilter(boolean abstractOk) {
1593 this.abstractOk = abstractOk;
1594 }
1596 public boolean accepts(Symbol s) {
1597 long flags = s.flags();
1598 return s.kind == MTH &&
1599 (flags & SYNTHETIC) == 0 &&
1600 (abstractOk ||
1601 (flags & DEFAULT) != 0 ||
1602 (flags & ABSTRACT) == 0);
1603 }
1604 };
1606 /** Find best qualified method matching given name, type and value
1607 * arguments.
1608 * @param env The current environment.
1609 * @param site The original type from where the selection
1610 * takes place.
1611 * @param name The method's name.
1612 * @param argtypes The method's value arguments.
1613 * @param typeargtypes The method's type arguments
1614 * @param allowBoxing Allow boxing conversions of arguments.
1615 * @param useVarargs Box trailing arguments into an array for varargs.
1616 */
1617 Symbol findMethod(Env<AttrContext> env,
1618 Type site,
1619 Name name,
1620 List<Type> argtypes,
1621 List<Type> typeargtypes,
1622 boolean allowBoxing,
1623 boolean useVarargs,
1624 boolean operator) {
1625 Symbol bestSoFar = methodNotFound;
1626 bestSoFar = findMethod(env,
1627 site,
1628 name,
1629 argtypes,
1630 typeargtypes,
1631 site.tsym.type,
1632 bestSoFar,
1633 allowBoxing,
1634 useVarargs,
1635 operator);
1636 return bestSoFar;
1637 }
1638 // where
1639 private Symbol findMethod(Env<AttrContext> env,
1640 Type site,
1641 Name name,
1642 List<Type> argtypes,
1643 List<Type> typeargtypes,
1644 Type intype,
1645 Symbol bestSoFar,
1646 boolean allowBoxing,
1647 boolean useVarargs,
1648 boolean operator) {
1649 @SuppressWarnings({"unchecked","rawtypes"})
1650 List<Type>[] itypes = (List<Type>[])new List[] { List.<Type>nil(), List.<Type>nil() };
1651 InterfaceLookupPhase iphase = InterfaceLookupPhase.ABSTRACT_OK;
1652 for (TypeSymbol s : superclasses(intype)) {
1653 bestSoFar = findMethodInScope(env, site, name, argtypes, typeargtypes,
1654 s.members(), bestSoFar, allowBoxing, useVarargs, operator, true);
1655 if (name == names.init) return bestSoFar;
1656 iphase = (iphase == null) ? null : iphase.update(s, this);
1657 if (iphase != null) {
1658 for (Type itype : types.interfaces(s.type)) {
1659 itypes[iphase.ordinal()] = types.union(types.closure(itype), itypes[iphase.ordinal()]);
1660 }
1661 }
1662 }
1664 Symbol concrete = bestSoFar.kind < ERR &&
1665 (bestSoFar.flags() & ABSTRACT) == 0 ?
1666 bestSoFar : methodNotFound;
1668 for (InterfaceLookupPhase iphase2 : InterfaceLookupPhase.values()) {
1669 if (iphase2 == InterfaceLookupPhase.DEFAULT_OK && !allowDefaultMethods) break;
1670 //keep searching for abstract methods
1671 for (Type itype : itypes[iphase2.ordinal()]) {
1672 if (!itype.isInterface()) continue; //skip j.l.Object (included by Types.closure())
1673 if (iphase2 == InterfaceLookupPhase.DEFAULT_OK &&
1674 (itype.tsym.flags() & DEFAULT) == 0) continue;
1675 bestSoFar = findMethodInScope(env, site, name, argtypes, typeargtypes,
1676 itype.tsym.members(), bestSoFar, allowBoxing, useVarargs, operator, true);
1677 if (concrete != bestSoFar &&
1678 concrete.kind < ERR && bestSoFar.kind < ERR &&
1679 types.isSubSignature(concrete.type, bestSoFar.type)) {
1680 //this is an hack - as javac does not do full membership checks
1681 //most specific ends up comparing abstract methods that might have
1682 //been implemented by some concrete method in a subclass and,
1683 //because of raw override, it is possible for an abstract method
1684 //to be more specific than the concrete method - so we need
1685 //to explicitly call that out (see CR 6178365)
1686 bestSoFar = concrete;
1687 }
1688 }
1689 }
1690 return bestSoFar;
1691 }
1693 enum InterfaceLookupPhase {
1694 ABSTRACT_OK() {
1695 @Override
1696 InterfaceLookupPhase update(Symbol s, Resolve rs) {
1697 //We should not look for abstract methods if receiver is a concrete class
1698 //(as concrete classes are expected to implement all abstracts coming
1699 //from superinterfaces)
1700 if ((s.flags() & (ABSTRACT | INTERFACE | ENUM)) != 0) {
1701 return this;
1702 } else if (rs.allowDefaultMethods) {
1703 return DEFAULT_OK;
1704 } else {
1705 return null;
1706 }
1707 }
1708 },
1709 DEFAULT_OK() {
1710 @Override
1711 InterfaceLookupPhase update(Symbol s, Resolve rs) {
1712 return this;
1713 }
1714 };
1716 abstract InterfaceLookupPhase update(Symbol s, Resolve rs);
1717 }
1719 /**
1720 * Return an Iterable object to scan the superclasses of a given type.
1721 * It's crucial that the scan is done lazily, as we don't want to accidentally
1722 * access more supertypes than strictly needed (as this could trigger completion
1723 * errors if some of the not-needed supertypes are missing/ill-formed).
1724 */
1725 Iterable<TypeSymbol> superclasses(final Type intype) {
1726 return new Iterable<TypeSymbol>() {
1727 public Iterator<TypeSymbol> iterator() {
1728 return new Iterator<TypeSymbol>() {
1730 List<TypeSymbol> seen = List.nil();
1731 TypeSymbol currentSym = symbolFor(intype);
1732 TypeSymbol prevSym = null;
1734 public boolean hasNext() {
1735 if (currentSym == syms.noSymbol) {
1736 currentSym = symbolFor(types.supertype(prevSym.type));
1737 }
1738 return currentSym != null;
1739 }
1741 public TypeSymbol next() {
1742 prevSym = currentSym;
1743 currentSym = syms.noSymbol;
1744 Assert.check(prevSym != null || prevSym != syms.noSymbol);
1745 return prevSym;
1746 }
1748 public void remove() {
1749 throw new UnsupportedOperationException();
1750 }
1752 TypeSymbol symbolFor(Type t) {
1753 if (!t.hasTag(CLASS) &&
1754 !t.hasTag(TYPEVAR)) {
1755 return null;
1756 }
1757 while (t.hasTag(TYPEVAR))
1758 t = t.getUpperBound();
1759 if (seen.contains(t.tsym)) {
1760 //degenerate case in which we have a circular
1761 //class hierarchy - because of ill-formed classfiles
1762 return null;
1763 }
1764 seen = seen.prepend(t.tsym);
1765 return t.tsym;
1766 }
1767 };
1768 }
1769 };
1770 }
1772 /** Find unqualified method matching given name, type and value arguments.
1773 * @param env The current environment.
1774 * @param name The method's name.
1775 * @param argtypes The method's value arguments.
1776 * @param typeargtypes The method's type arguments.
1777 * @param allowBoxing Allow boxing conversions of arguments.
1778 * @param useVarargs Box trailing arguments into an array for varargs.
1779 */
1780 Symbol findFun(Env<AttrContext> env, Name name,
1781 List<Type> argtypes, List<Type> typeargtypes,
1782 boolean allowBoxing, boolean useVarargs) {
1783 Symbol bestSoFar = methodNotFound;
1784 Symbol sym;
1785 Env<AttrContext> env1 = env;
1786 boolean staticOnly = false;
1787 while (env1.outer != null) {
1788 if (isStatic(env1)) staticOnly = true;
1789 sym = findMethod(
1790 env1, env1.enclClass.sym.type, name, argtypes, typeargtypes,
1791 allowBoxing, useVarargs, false);
1792 if (sym.exists()) {
1793 if (staticOnly &&
1794 sym.kind == MTH &&
1795 sym.owner.kind == TYP &&
1796 (sym.flags() & STATIC) == 0) return new StaticError(sym);
1797 else return sym;
1798 } else if (sym.kind < bestSoFar.kind) {
1799 bestSoFar = sym;
1800 }
1801 if ((env1.enclClass.sym.flags() & STATIC) != 0) staticOnly = true;
1802 env1 = env1.outer;
1803 }
1805 sym = findMethod(env, syms.predefClass.type, name, argtypes,
1806 typeargtypes, allowBoxing, useVarargs, false);
1807 if (sym.exists())
1808 return sym;
1810 Scope.Entry e = env.toplevel.namedImportScope.lookup(name);
1811 for (; e.scope != null; e = e.next()) {
1812 sym = e.sym;
1813 Type origin = e.getOrigin().owner.type;
1814 if (sym.kind == MTH) {
1815 if (e.sym.owner.type != origin)
1816 sym = sym.clone(e.getOrigin().owner);
1817 if (!isAccessible(env, origin, sym))
1818 sym = new AccessError(env, origin, sym);
1819 bestSoFar = selectBest(env, origin,
1820 argtypes, typeargtypes,
1821 sym, bestSoFar,
1822 allowBoxing, useVarargs, false);
1823 }
1824 }
1825 if (bestSoFar.exists())
1826 return bestSoFar;
1828 e = env.toplevel.starImportScope.lookup(name);
1829 for (; e.scope != null; e = e.next()) {
1830 sym = e.sym;
1831 Type origin = e.getOrigin().owner.type;
1832 if (sym.kind == MTH) {
1833 if (e.sym.owner.type != origin)
1834 sym = sym.clone(e.getOrigin().owner);
1835 if (!isAccessible(env, origin, sym))
1836 sym = new AccessError(env, origin, sym);
1837 bestSoFar = selectBest(env, origin,
1838 argtypes, typeargtypes,
1839 sym, bestSoFar,
1840 allowBoxing, useVarargs, false);
1841 }
1842 }
1843 return bestSoFar;
1844 }
1846 /** Load toplevel or member class with given fully qualified name and
1847 * verify that it is accessible.
1848 * @param env The current environment.
1849 * @param name The fully qualified name of the class to be loaded.
1850 */
1851 Symbol loadClass(Env<AttrContext> env, Name name) {
1852 try {
1853 ClassSymbol c = reader.loadClass(name);
1854 return isAccessible(env, c) ? c : new AccessError(c);
1855 } catch (ClassReader.BadClassFile err) {
1856 throw err;
1857 } catch (CompletionFailure ex) {
1858 return typeNotFound;
1859 }
1860 }
1862 /** Find qualified member type.
1863 * @param env The current environment.
1864 * @param site The original type from where the selection takes
1865 * place.
1866 * @param name The type's name.
1867 * @param c The class to search for the member type. This is
1868 * always a superclass or implemented interface of
1869 * site's class.
1870 */
1871 Symbol findMemberType(Env<AttrContext> env,
1872 Type site,
1873 Name name,
1874 TypeSymbol c) {
1875 Symbol bestSoFar = typeNotFound;
1876 Symbol sym;
1877 Scope.Entry e = c.members().lookup(name);
1878 while (e.scope != null) {
1879 if (e.sym.kind == TYP) {
1880 return isAccessible(env, site, e.sym)
1881 ? e.sym
1882 : new AccessError(env, site, e.sym);
1883 }
1884 e = e.next();
1885 }
1886 Type st = types.supertype(c.type);
1887 if (st != null && st.hasTag(CLASS)) {
1888 sym = findMemberType(env, site, name, st.tsym);
1889 if (sym.kind < bestSoFar.kind) bestSoFar = sym;
1890 }
1891 for (List<Type> l = types.interfaces(c.type);
1892 bestSoFar.kind != AMBIGUOUS && l.nonEmpty();
1893 l = l.tail) {
1894 sym = findMemberType(env, site, name, l.head.tsym);
1895 if (bestSoFar.kind < AMBIGUOUS && sym.kind < AMBIGUOUS &&
1896 sym.owner != bestSoFar.owner)
1897 bestSoFar = new AmbiguityError(bestSoFar, sym);
1898 else if (sym.kind < bestSoFar.kind)
1899 bestSoFar = sym;
1900 }
1901 return bestSoFar;
1902 }
1904 /** Find a global type in given scope and load corresponding class.
1905 * @param env The current environment.
1906 * @param scope The scope in which to look for the type.
1907 * @param name The type's name.
1908 */
1909 Symbol findGlobalType(Env<AttrContext> env, Scope scope, Name name) {
1910 Symbol bestSoFar = typeNotFound;
1911 for (Scope.Entry e = scope.lookup(name); e.scope != null; e = e.next()) {
1912 Symbol sym = loadClass(env, e.sym.flatName());
1913 if (bestSoFar.kind == TYP && sym.kind == TYP &&
1914 bestSoFar != sym)
1915 return new AmbiguityError(bestSoFar, sym);
1916 else if (sym.kind < bestSoFar.kind)
1917 bestSoFar = sym;
1918 }
1919 return bestSoFar;
1920 }
1922 /** Find an unqualified type symbol.
1923 * @param env The current environment.
1924 * @param name The type's name.
1925 */
1926 Symbol findType(Env<AttrContext> env, Name name) {
1927 Symbol bestSoFar = typeNotFound;
1928 Symbol sym;
1929 boolean staticOnly = false;
1930 for (Env<AttrContext> env1 = env; env1.outer != null; env1 = env1.outer) {
1931 if (isStatic(env1)) staticOnly = true;
1932 for (Scope.Entry e = env1.info.scope.lookup(name);
1933 e.scope != null;
1934 e = e.next()) {
1935 if (e.sym.kind == TYP) {
1936 if (staticOnly &&
1937 e.sym.type.hasTag(TYPEVAR) &&
1938 e.sym.owner.kind == TYP) return new StaticError(e.sym);
1939 return e.sym;
1940 }
1941 }
1943 sym = findMemberType(env1, env1.enclClass.sym.type, name,
1944 env1.enclClass.sym);
1945 if (staticOnly && sym.kind == TYP &&
1946 sym.type.hasTag(CLASS) &&
1947 sym.type.getEnclosingType().hasTag(CLASS) &&
1948 env1.enclClass.sym.type.isParameterized() &&
1949 sym.type.getEnclosingType().isParameterized())
1950 return new StaticError(sym);
1951 else if (sym.exists()) return sym;
1952 else if (sym.kind < bestSoFar.kind) bestSoFar = sym;
1954 JCClassDecl encl = env1.baseClause ? (JCClassDecl)env1.tree : env1.enclClass;
1955 if ((encl.sym.flags() & STATIC) != 0)
1956 staticOnly = true;
1957 }
1959 if (!env.tree.hasTag(IMPORT)) {
1960 sym = findGlobalType(env, env.toplevel.namedImportScope, name);
1961 if (sym.exists()) return sym;
1962 else if (sym.kind < bestSoFar.kind) bestSoFar = sym;
1964 sym = findGlobalType(env, env.toplevel.packge.members(), name);
1965 if (sym.exists()) return sym;
1966 else if (sym.kind < bestSoFar.kind) bestSoFar = sym;
1968 sym = findGlobalType(env, env.toplevel.starImportScope, name);
1969 if (sym.exists()) return sym;
1970 else if (sym.kind < bestSoFar.kind) bestSoFar = sym;
1971 }
1973 return bestSoFar;
1974 }
1976 /** Find an unqualified identifier which matches a specified kind set.
1977 * @param env The current environment.
1978 * @param name The identifier's name.
1979 * @param kind Indicates the possible symbol kinds
1980 * (a subset of VAL, TYP, PCK).
1981 */
1982 Symbol findIdent(Env<AttrContext> env, Name name, int kind) {
1983 Symbol bestSoFar = typeNotFound;
1984 Symbol sym;
1986 if ((kind & VAR) != 0) {
1987 sym = findVar(env, name);
1988 if (sym.exists()) return sym;
1989 else if (sym.kind < bestSoFar.kind) bestSoFar = sym;
1990 }
1992 if ((kind & TYP) != 0) {
1993 sym = findType(env, name);
1994 if (sym.kind==TYP) {
1995 reportDependence(env.enclClass.sym, sym);
1996 }
1997 if (sym.exists()) return sym;
1998 else if (sym.kind < bestSoFar.kind) bestSoFar = sym;
1999 }
2001 if ((kind & PCK) != 0) return reader.enterPackage(name);
2002 else return bestSoFar;
2003 }
2005 /** Report dependencies.
2006 * @param from The enclosing class sym
2007 * @param to The found identifier that the class depends on.
2008 */
2009 public void reportDependence(Symbol from, Symbol to) {
2010 // Override if you want to collect the reported dependencies.
2011 }
2013 /** Find an identifier in a package which matches a specified kind set.
2014 * @param env The current environment.
2015 * @param name The identifier's name.
2016 * @param kind Indicates the possible symbol kinds
2017 * (a nonempty subset of TYP, PCK).
2018 */
2019 Symbol findIdentInPackage(Env<AttrContext> env, TypeSymbol pck,
2020 Name name, int kind) {
2021 Name fullname = TypeSymbol.formFullName(name, pck);
2022 Symbol bestSoFar = typeNotFound;
2023 PackageSymbol pack = null;
2024 if ((kind & PCK) != 0) {
2025 pack = reader.enterPackage(fullname);
2026 if (pack.exists()) return pack;
2027 }
2028 if ((kind & TYP) != 0) {
2029 Symbol sym = loadClass(env, fullname);
2030 if (sym.exists()) {
2031 // don't allow programs to use flatnames
2032 if (name == sym.name) return sym;
2033 }
2034 else if (sym.kind < bestSoFar.kind) bestSoFar = sym;
2035 }
2036 return (pack != null) ? pack : bestSoFar;
2037 }
2039 /** Find an identifier among the members of a given type `site'.
2040 * @param env The current environment.
2041 * @param site The type containing the symbol to be found.
2042 * @param name The identifier's name.
2043 * @param kind Indicates the possible symbol kinds
2044 * (a subset of VAL, TYP).
2045 */
2046 Symbol findIdentInType(Env<AttrContext> env, Type site,
2047 Name name, int kind) {
2048 Symbol bestSoFar = typeNotFound;
2049 Symbol sym;
2050 if ((kind & VAR) != 0) {
2051 sym = findField(env, site, name, site.tsym);
2052 if (sym.exists()) return sym;
2053 else if (sym.kind < bestSoFar.kind) bestSoFar = sym;
2054 }
2056 if ((kind & TYP) != 0) {
2057 sym = findMemberType(env, site, name, site.tsym);
2058 if (sym.exists()) return sym;
2059 else if (sym.kind < bestSoFar.kind) bestSoFar = sym;
2060 }
2061 return bestSoFar;
2062 }
2064 /* ***************************************************************************
2065 * Access checking
2066 * The following methods convert ResolveErrors to ErrorSymbols, issuing
2067 * an error message in the process
2068 ****************************************************************************/
2070 /** If `sym' is a bad symbol: report error and return errSymbol
2071 * else pass through unchanged,
2072 * additional arguments duplicate what has been used in trying to find the
2073 * symbol {@literal (--> flyweight pattern)}. This improves performance since we
2074 * expect misses to happen frequently.
2075 *
2076 * @param sym The symbol that was found, or a ResolveError.
2077 * @param pos The position to use for error reporting.
2078 * @param location The symbol the served as a context for this lookup
2079 * @param site The original type from where the selection took place.
2080 * @param name The symbol's name.
2081 * @param qualified Did we get here through a qualified expression resolution?
2082 * @param argtypes The invocation's value arguments,
2083 * if we looked for a method.
2084 * @param typeargtypes The invocation's type arguments,
2085 * if we looked for a method.
2086 * @param logResolveHelper helper class used to log resolve errors
2087 */
2088 Symbol accessInternal(Symbol sym,
2089 DiagnosticPosition pos,
2090 Symbol location,
2091 Type site,
2092 Name name,
2093 boolean qualified,
2094 List<Type> argtypes,
2095 List<Type> typeargtypes,
2096 LogResolveHelper logResolveHelper) {
2097 if (sym.kind >= AMBIGUOUS) {
2098 ResolveError errSym = (ResolveError)sym;
2099 sym = errSym.access(name, qualified ? site.tsym : syms.noSymbol);
2100 argtypes = logResolveHelper.getArgumentTypes(errSym, sym, name, argtypes);
2101 if (logResolveHelper.resolveDiagnosticNeeded(site, argtypes, typeargtypes)) {
2102 logResolveError(errSym, pos, location, site, name, argtypes, typeargtypes);
2103 }
2104 }
2105 return sym;
2106 }
2108 /**
2109 * Variant of the generalized access routine, to be used for generating method
2110 * resolution diagnostics
2111 */
2112 Symbol accessMethod(Symbol sym,
2113 DiagnosticPosition pos,
2114 Symbol location,
2115 Type site,
2116 Name name,
2117 boolean qualified,
2118 List<Type> argtypes,
2119 List<Type> typeargtypes) {
2120 return accessInternal(sym, pos, location, site, name, qualified, argtypes, typeargtypes, methodLogResolveHelper);
2121 }
2123 /** Same as original accessMethod(), but without location.
2124 */
2125 Symbol accessMethod(Symbol sym,
2126 DiagnosticPosition pos,
2127 Type site,
2128 Name name,
2129 boolean qualified,
2130 List<Type> argtypes,
2131 List<Type> typeargtypes) {
2132 return accessMethod(sym, pos, site.tsym, site, name, qualified, argtypes, typeargtypes);
2133 }
2135 /**
2136 * Variant of the generalized access routine, to be used for generating variable,
2137 * type resolution diagnostics
2138 */
2139 Symbol accessBase(Symbol sym,
2140 DiagnosticPosition pos,
2141 Symbol location,
2142 Type site,
2143 Name name,
2144 boolean qualified) {
2145 return accessInternal(sym, pos, location, site, name, qualified, List.<Type>nil(), null, basicLogResolveHelper);
2146 }
2148 /** Same as original accessBase(), but without location.
2149 */
2150 Symbol accessBase(Symbol sym,
2151 DiagnosticPosition pos,
2152 Type site,
2153 Name name,
2154 boolean qualified) {
2155 return accessBase(sym, pos, site.tsym, site, name, qualified);
2156 }
2158 interface LogResolveHelper {
2159 boolean resolveDiagnosticNeeded(Type site, List<Type> argtypes, List<Type> typeargtypes);
2160 List<Type> getArgumentTypes(ResolveError errSym, Symbol accessedSym, Name name, List<Type> argtypes);
2161 }
2163 LogResolveHelper basicLogResolveHelper = new LogResolveHelper() {
2164 public boolean resolveDiagnosticNeeded(Type site, List<Type> argtypes, List<Type> typeargtypes) {
2165 return !site.isErroneous();
2166 }
2167 public List<Type> getArgumentTypes(ResolveError errSym, Symbol accessedSym, Name name, List<Type> argtypes) {
2168 return argtypes;
2169 }
2170 };
2172 LogResolveHelper methodLogResolveHelper = new LogResolveHelper() {
2173 public boolean resolveDiagnosticNeeded(Type site, List<Type> argtypes, List<Type> typeargtypes) {
2174 return !site.isErroneous() &&
2175 !Type.isErroneous(argtypes) &&
2176 (typeargtypes == null || !Type.isErroneous(typeargtypes));
2177 }
2178 public List<Type> getArgumentTypes(ResolveError errSym, Symbol accessedSym, Name name, List<Type> argtypes) {
2179 return (syms.operatorNames.contains(name)) ?
2180 argtypes :
2181 Type.map(argtypes, new ResolveDeferredRecoveryMap(accessedSym));
2182 }
2184 class ResolveDeferredRecoveryMap extends DeferredAttr.RecoveryDeferredTypeMap {
2186 public ResolveDeferredRecoveryMap(Symbol msym) {
2187 deferredAttr.super(AttrMode.SPECULATIVE, msym, currentResolutionContext.step);
2188 }
2190 @Override
2191 protected Type typeOf(DeferredType dt) {
2192 Type res = super.typeOf(dt);
2193 if (!res.isErroneous()) {
2194 switch (TreeInfo.skipParens(dt.tree).getTag()) {
2195 case LAMBDA:
2196 case REFERENCE:
2197 return dt;
2198 case CONDEXPR:
2199 return res == Type.recoveryType ?
2200 dt : res;
2201 }
2202 }
2203 return res;
2204 }
2205 }
2206 };
2208 /** Check that sym is not an abstract method.
2209 */
2210 void checkNonAbstract(DiagnosticPosition pos, Symbol sym) {
2211 if ((sym.flags() & ABSTRACT) != 0 && (sym.flags() & DEFAULT) == 0)
2212 log.error(pos, "abstract.cant.be.accessed.directly",
2213 kindName(sym), sym, sym.location());
2214 }
2216 /* ***************************************************************************
2217 * Debugging
2218 ****************************************************************************/
2220 /** print all scopes starting with scope s and proceeding outwards.
2221 * used for debugging.
2222 */
2223 public void printscopes(Scope s) {
2224 while (s != null) {
2225 if (s.owner != null)
2226 System.err.print(s.owner + ": ");
2227 for (Scope.Entry e = s.elems; e != null; e = e.sibling) {
2228 if ((e.sym.flags() & ABSTRACT) != 0)
2229 System.err.print("abstract ");
2230 System.err.print(e.sym + " ");
2231 }
2232 System.err.println();
2233 s = s.next;
2234 }
2235 }
2237 void printscopes(Env<AttrContext> env) {
2238 while (env.outer != null) {
2239 System.err.println("------------------------------");
2240 printscopes(env.info.scope);
2241 env = env.outer;
2242 }
2243 }
2245 public void printscopes(Type t) {
2246 while (t.hasTag(CLASS)) {
2247 printscopes(t.tsym.members());
2248 t = types.supertype(t);
2249 }
2250 }
2252 /* ***************************************************************************
2253 * Name resolution
2254 * Naming conventions are as for symbol lookup
2255 * Unlike the find... methods these methods will report access errors
2256 ****************************************************************************/
2258 /** Resolve an unqualified (non-method) identifier.
2259 * @param pos The position to use for error reporting.
2260 * @param env The environment current at the identifier use.
2261 * @param name The identifier's name.
2262 * @param kind The set of admissible symbol kinds for the identifier.
2263 */
2264 Symbol resolveIdent(DiagnosticPosition pos, Env<AttrContext> env,
2265 Name name, int kind) {
2266 return accessBase(
2267 findIdent(env, name, kind),
2268 pos, env.enclClass.sym.type, name, false);
2269 }
2271 /** Resolve an unqualified method identifier.
2272 * @param pos The position to use for error reporting.
2273 * @param env The environment current at the method invocation.
2274 * @param name The identifier's name.
2275 * @param argtypes The types of the invocation's value arguments.
2276 * @param typeargtypes The types of the invocation's type arguments.
2277 */
2278 Symbol resolveMethod(DiagnosticPosition pos,
2279 Env<AttrContext> env,
2280 Name name,
2281 List<Type> argtypes,
2282 List<Type> typeargtypes) {
2283 return lookupMethod(env, pos, env.enclClass.sym, resolveMethodCheck,
2284 new BasicLookupHelper(name, env.enclClass.sym.type, argtypes, typeargtypes) {
2285 @Override
2286 Symbol doLookup(Env<AttrContext> env, MethodResolutionPhase phase) {
2287 return findFun(env, name, argtypes, typeargtypes,
2288 phase.isBoxingRequired(),
2289 phase.isVarargsRequired());
2290 }});
2291 }
2293 /** Resolve a qualified method identifier
2294 * @param pos The position to use for error reporting.
2295 * @param env The environment current at the method invocation.
2296 * @param site The type of the qualifying expression, in which
2297 * identifier is searched.
2298 * @param name The identifier's name.
2299 * @param argtypes The types of the invocation's value arguments.
2300 * @param typeargtypes The types of the invocation's type arguments.
2301 */
2302 Symbol resolveQualifiedMethod(DiagnosticPosition pos, Env<AttrContext> env,
2303 Type site, Name name, List<Type> argtypes,
2304 List<Type> typeargtypes) {
2305 return resolveQualifiedMethod(pos, env, site.tsym, site, name, argtypes, typeargtypes);
2306 }
2307 Symbol resolveQualifiedMethod(DiagnosticPosition pos, Env<AttrContext> env,
2308 Symbol location, Type site, Name name, List<Type> argtypes,
2309 List<Type> typeargtypes) {
2310 return resolveQualifiedMethod(new MethodResolutionContext(), pos, env, location, site, name, argtypes, typeargtypes);
2311 }
2312 private Symbol resolveQualifiedMethod(MethodResolutionContext resolveContext,
2313 DiagnosticPosition pos, Env<AttrContext> env,
2314 Symbol location, Type site, Name name, List<Type> argtypes,
2315 List<Type> typeargtypes) {
2316 return lookupMethod(env, pos, location, resolveContext, new BasicLookupHelper(name, site, argtypes, typeargtypes) {
2317 @Override
2318 Symbol doLookup(Env<AttrContext> env, MethodResolutionPhase phase) {
2319 return findMethod(env, site, name, argtypes, typeargtypes,
2320 phase.isBoxingRequired(),
2321 phase.isVarargsRequired(), false);
2322 }
2323 @Override
2324 Symbol access(Env<AttrContext> env, DiagnosticPosition pos, Symbol location, Symbol sym) {
2325 if (sym.kind >= AMBIGUOUS) {
2326 sym = super.access(env, pos, location, sym);
2327 } else if (allowMethodHandles) {
2328 MethodSymbol msym = (MethodSymbol)sym;
2329 if ((msym.flags() & SIGNATURE_POLYMORPHIC) != 0) {
2330 return findPolymorphicSignatureInstance(env, sym, argtypes);
2331 }
2332 }
2333 return sym;
2334 }
2335 });
2336 }
2338 /** Find or create an implicit method of exactly the given type (after erasure).
2339 * Searches in a side table, not the main scope of the site.
2340 * This emulates the lookup process required by JSR 292 in JVM.
2341 * @param env Attribution environment
2342 * @param spMethod signature polymorphic method - i.e. MH.invokeExact
2343 * @param argtypes The required argument types
2344 */
2345 Symbol findPolymorphicSignatureInstance(Env<AttrContext> env,
2346 final Symbol spMethod,
2347 List<Type> argtypes) {
2348 Type mtype = infer.instantiatePolymorphicSignatureInstance(env,
2349 (MethodSymbol)spMethod, currentResolutionContext, argtypes);
2350 for (Symbol sym : polymorphicSignatureScope.getElementsByName(spMethod.name)) {
2351 if (types.isSameType(mtype, sym.type)) {
2352 return sym;
2353 }
2354 }
2356 // create the desired method
2357 long flags = ABSTRACT | HYPOTHETICAL | spMethod.flags() & Flags.AccessFlags;
2358 Symbol msym = new MethodSymbol(flags, spMethod.name, mtype, spMethod.owner) {
2359 @Override
2360 public Symbol baseSymbol() {
2361 return spMethod;
2362 }
2363 };
2364 polymorphicSignatureScope.enter(msym);
2365 return msym;
2366 }
2368 /** Resolve a qualified method identifier, throw a fatal error if not
2369 * found.
2370 * @param pos The position to use for error reporting.
2371 * @param env The environment current at the method invocation.
2372 * @param site The type of the qualifying expression, in which
2373 * identifier is searched.
2374 * @param name The identifier's name.
2375 * @param argtypes The types of the invocation's value arguments.
2376 * @param typeargtypes The types of the invocation's type arguments.
2377 */
2378 public MethodSymbol resolveInternalMethod(DiagnosticPosition pos, Env<AttrContext> env,
2379 Type site, Name name,
2380 List<Type> argtypes,
2381 List<Type> typeargtypes) {
2382 MethodResolutionContext resolveContext = new MethodResolutionContext();
2383 resolveContext.internalResolution = true;
2384 Symbol sym = resolveQualifiedMethod(resolveContext, pos, env, site.tsym,
2385 site, name, argtypes, typeargtypes);
2386 if (sym.kind == MTH) return (MethodSymbol)sym;
2387 else throw new FatalError(
2388 diags.fragment("fatal.err.cant.locate.meth",
2389 name));
2390 }
2392 /** Resolve constructor.
2393 * @param pos The position to use for error reporting.
2394 * @param env The environment current at the constructor invocation.
2395 * @param site The type of class for which a constructor is searched.
2396 * @param argtypes The types of the constructor invocation's value
2397 * arguments.
2398 * @param typeargtypes The types of the constructor invocation's type
2399 * arguments.
2400 */
2401 Symbol resolveConstructor(DiagnosticPosition pos,
2402 Env<AttrContext> env,
2403 Type site,
2404 List<Type> argtypes,
2405 List<Type> typeargtypes) {
2406 return resolveConstructor(new MethodResolutionContext(), pos, env, site, argtypes, typeargtypes);
2407 }
2409 private Symbol resolveConstructor(MethodResolutionContext resolveContext,
2410 final DiagnosticPosition pos,
2411 Env<AttrContext> env,
2412 Type site,
2413 List<Type> argtypes,
2414 List<Type> typeargtypes) {
2415 return lookupMethod(env, pos, site.tsym, resolveContext, new BasicLookupHelper(names.init, site, argtypes, typeargtypes) {
2416 @Override
2417 Symbol doLookup(Env<AttrContext> env, MethodResolutionPhase phase) {
2418 return findConstructor(pos, env, site, argtypes, typeargtypes,
2419 phase.isBoxingRequired(),
2420 phase.isVarargsRequired());
2421 }
2422 });
2423 }
2425 /** Resolve a constructor, throw a fatal error if not found.
2426 * @param pos The position to use for error reporting.
2427 * @param env The environment current at the method invocation.
2428 * @param site The type to be constructed.
2429 * @param argtypes The types of the invocation's value arguments.
2430 * @param typeargtypes The types of the invocation's type arguments.
2431 */
2432 public MethodSymbol resolveInternalConstructor(DiagnosticPosition pos, Env<AttrContext> env,
2433 Type site,
2434 List<Type> argtypes,
2435 List<Type> typeargtypes) {
2436 MethodResolutionContext resolveContext = new MethodResolutionContext();
2437 resolveContext.internalResolution = true;
2438 Symbol sym = resolveConstructor(resolveContext, pos, env, site, argtypes, typeargtypes);
2439 if (sym.kind == MTH) return (MethodSymbol)sym;
2440 else throw new FatalError(
2441 diags.fragment("fatal.err.cant.locate.ctor", site));
2442 }
2444 Symbol findConstructor(DiagnosticPosition pos, Env<AttrContext> env,
2445 Type site, List<Type> argtypes,
2446 List<Type> typeargtypes,
2447 boolean allowBoxing,
2448 boolean useVarargs) {
2449 Symbol sym = findMethod(env, site,
2450 names.init, argtypes,
2451 typeargtypes, allowBoxing,
2452 useVarargs, false);
2453 chk.checkDeprecated(pos, env.info.scope.owner, sym);
2454 return sym;
2455 }
2457 /** Resolve constructor using diamond inference.
2458 * @param pos The position to use for error reporting.
2459 * @param env The environment current at the constructor invocation.
2460 * @param site The type of class for which a constructor is searched.
2461 * The scope of this class has been touched in attribution.
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 resolveDiamond(DiagnosticPosition pos,
2468 Env<AttrContext> env,
2469 Type site,
2470 List<Type> argtypes,
2471 List<Type> typeargtypes) {
2472 return lookupMethod(env, pos, site.tsym, resolveMethodCheck,
2473 new BasicLookupHelper(names.init, site, argtypes, typeargtypes) {
2474 @Override
2475 Symbol doLookup(Env<AttrContext> env, MethodResolutionPhase phase) {
2476 return findDiamond(env, site, argtypes, typeargtypes,
2477 phase.isBoxingRequired(),
2478 phase.isVarargsRequired());
2479 }
2480 @Override
2481 Symbol access(Env<AttrContext> env, DiagnosticPosition pos, Symbol location, Symbol sym) {
2482 if (sym.kind >= AMBIGUOUS) {
2483 final JCDiagnostic details = sym.kind == WRONG_MTH ?
2484 ((InapplicableSymbolError)sym).errCandidate().snd :
2485 null;
2486 sym = new InapplicableSymbolError(sym.kind, "diamondError", currentResolutionContext) {
2487 @Override
2488 JCDiagnostic getDiagnostic(DiagnosticType dkind, DiagnosticPosition pos,
2489 Symbol location, Type site, Name name, List<Type> argtypes, List<Type> typeargtypes) {
2490 String key = details == null ?
2491 "cant.apply.diamond" :
2492 "cant.apply.diamond.1";
2493 return diags.create(dkind, log.currentSource(), pos, key,
2494 diags.fragment("diamond", site.tsym), details);
2495 }
2496 };
2497 sym = accessMethod(sym, pos, site, names.init, true, argtypes, typeargtypes);
2498 env.info.pendingResolutionPhase = currentResolutionContext.step;
2499 }
2500 return sym;
2501 }});
2502 }
2504 /** This method scans all the constructor symbol in a given class scope -
2505 * assuming that the original scope contains a constructor of the kind:
2506 * {@code Foo(X x, Y y)}, where X,Y are class type-variables declared in Foo,
2507 * a method check is executed against the modified constructor type:
2508 * {@code <X,Y>Foo<X,Y>(X x, Y y)}. This is crucial in order to enable diamond
2509 * inference. The inferred return type of the synthetic constructor IS
2510 * the inferred type for the diamond operator.
2511 */
2512 private Symbol findDiamond(Env<AttrContext> env,
2513 Type site,
2514 List<Type> argtypes,
2515 List<Type> typeargtypes,
2516 boolean allowBoxing,
2517 boolean useVarargs) {
2518 Symbol bestSoFar = methodNotFound;
2519 for (Scope.Entry e = site.tsym.members().lookup(names.init);
2520 e.scope != null;
2521 e = e.next()) {
2522 final Symbol sym = e.sym;
2523 //- System.out.println(" e " + e.sym);
2524 if (sym.kind == MTH &&
2525 (sym.flags_field & SYNTHETIC) == 0) {
2526 List<Type> oldParams = e.sym.type.hasTag(FORALL) ?
2527 ((ForAll)sym.type).tvars :
2528 List.<Type>nil();
2529 Type constrType = new ForAll(site.tsym.type.getTypeArguments().appendList(oldParams),
2530 types.createMethodTypeWithReturn(sym.type.asMethodType(), site));
2531 MethodSymbol newConstr = new MethodSymbol(sym.flags(), names.init, constrType, site.tsym) {
2532 @Override
2533 public Symbol baseSymbol() {
2534 return sym;
2535 }
2536 };
2537 bestSoFar = selectBest(env, site, argtypes, typeargtypes,
2538 newConstr,
2539 bestSoFar,
2540 allowBoxing,
2541 useVarargs,
2542 false);
2543 }
2544 }
2545 return bestSoFar;
2546 }
2550 /** Resolve operator.
2551 * @param pos The position to use for error reporting.
2552 * @param optag The tag of the operation tree.
2553 * @param env The environment current at the operation.
2554 * @param argtypes The types of the operands.
2555 */
2556 Symbol resolveOperator(DiagnosticPosition pos, JCTree.Tag optag,
2557 Env<AttrContext> env, List<Type> argtypes) {
2558 MethodResolutionContext prevResolutionContext = currentResolutionContext;
2559 try {
2560 currentResolutionContext = new MethodResolutionContext();
2561 Name name = treeinfo.operatorName(optag);
2562 return lookupMethod(env, pos, syms.predefClass, currentResolutionContext,
2563 new BasicLookupHelper(name, syms.predefClass.type, argtypes, null, BOX) {
2564 @Override
2565 Symbol doLookup(Env<AttrContext> env, MethodResolutionPhase phase) {
2566 return findMethod(env, site, name, argtypes, typeargtypes,
2567 phase.isBoxingRequired(),
2568 phase.isVarargsRequired(), true);
2569 }
2570 @Override
2571 Symbol access(Env<AttrContext> env, DiagnosticPosition pos, Symbol location, Symbol sym) {
2572 return accessMethod(sym, pos, env.enclClass.sym.type, name,
2573 false, argtypes, null);
2574 }
2575 });
2576 } finally {
2577 currentResolutionContext = prevResolutionContext;
2578 }
2579 }
2581 /** Resolve operator.
2582 * @param pos The position to use for error reporting.
2583 * @param optag The tag of the operation tree.
2584 * @param env The environment current at the operation.
2585 * @param arg The type of the operand.
2586 */
2587 Symbol resolveUnaryOperator(DiagnosticPosition pos, JCTree.Tag optag, Env<AttrContext> env, Type arg) {
2588 return resolveOperator(pos, optag, env, List.of(arg));
2589 }
2591 /** Resolve binary operator.
2592 * @param pos The position to use for error reporting.
2593 * @param optag The tag of the operation tree.
2594 * @param env The environment current at the operation.
2595 * @param left The types of the left operand.
2596 * @param right The types of the right operand.
2597 */
2598 Symbol resolveBinaryOperator(DiagnosticPosition pos,
2599 JCTree.Tag optag,
2600 Env<AttrContext> env,
2601 Type left,
2602 Type right) {
2603 return resolveOperator(pos, optag, env, List.of(left, right));
2604 }
2606 /**
2607 * Resolution of member references is typically done as a single
2608 * overload resolution step, where the argument types A are inferred from
2609 * the target functional descriptor.
2610 *
2611 * If the member reference is a method reference with a type qualifier,
2612 * a two-step lookup process is performed. The first step uses the
2613 * expected argument list A, while the second step discards the first
2614 * type from A (which is treated as a receiver type).
2615 *
2616 * There are two cases in which inference is performed: (i) if the member
2617 * reference is a constructor reference and the qualifier type is raw - in
2618 * which case diamond inference is used to infer a parameterization for the
2619 * type qualifier; (ii) if the member reference is an unbound reference
2620 * where the type qualifier is raw - in that case, during the unbound lookup
2621 * the receiver argument type is used to infer an instantiation for the raw
2622 * qualifier type.
2623 *
2624 * When a multi-step resolution process is exploited, it is an error
2625 * if two candidates are found (ambiguity).
2626 *
2627 * This routine returns a pair (T,S), where S is the member reference symbol,
2628 * and T is the type of the class in which S is defined. This is necessary as
2629 * the type T might be dynamically inferred (i.e. if constructor reference
2630 * has a raw qualifier).
2631 */
2632 Pair<Symbol, ReferenceLookupHelper> resolveMemberReference(DiagnosticPosition pos,
2633 Env<AttrContext> env,
2634 JCMemberReference referenceTree,
2635 Type site,
2636 Name name, List<Type> argtypes,
2637 List<Type> typeargtypes,
2638 boolean boxingAllowed,
2639 MethodCheck methodCheck,
2640 InferenceContext inferenceContext) {
2641 MethodResolutionPhase maxPhase = boxingAllowed ? VARARITY : BASIC;
2643 if (site.hasTag(TYPEVAR)) {
2644 return resolveMemberReference(pos, env, referenceTree, site.getUpperBound(),
2645 name, argtypes, typeargtypes, boxingAllowed, methodCheck, inferenceContext);
2646 }
2648 site = types.capture(site);
2650 ReferenceLookupHelper boundLookupHelper;
2651 if (!name.equals(names.init)) {
2652 //method reference
2653 boundLookupHelper =
2654 new MethodReferenceLookupHelper(referenceTree, name, site, argtypes, typeargtypes, maxPhase);
2655 } else if (site.hasTag(ARRAY)) {
2656 //array constructor reference
2657 boundLookupHelper =
2658 new ArrayConstructorReferenceLookupHelper(referenceTree, site, argtypes, typeargtypes, maxPhase);
2659 } else {
2660 //class constructor reference
2661 boundLookupHelper =
2662 new ConstructorReferenceLookupHelper(referenceTree, site, argtypes, typeargtypes, maxPhase);
2663 }
2665 //step 1 - bound lookup
2666 Env<AttrContext> boundEnv = env.dup(env.tree, env.info.dup());
2667 Symbol boundSym = lookupMethod(boundEnv, env.tree.pos(), site.tsym, methodCheck, boundLookupHelper);
2669 //step 2 - unbound lookup
2670 ReferenceLookupHelper unboundLookupHelper = boundLookupHelper.unboundLookup(inferenceContext);
2671 Env<AttrContext> unboundEnv = env.dup(env.tree, env.info.dup());
2672 Symbol unboundSym = lookupMethod(unboundEnv, env.tree.pos(), site.tsym, methodCheck, unboundLookupHelper);
2674 //merge results
2675 Pair<Symbol, ReferenceLookupHelper> res;
2676 Symbol bestSym = choose(boundSym, unboundSym);
2677 res = new Pair<Symbol, ReferenceLookupHelper>(bestSym,
2678 bestSym == unboundSym ? unboundLookupHelper : boundLookupHelper);
2679 env.info.pendingResolutionPhase = bestSym == unboundSym ?
2680 unboundEnv.info.pendingResolutionPhase :
2681 boundEnv.info.pendingResolutionPhase;
2683 return res;
2684 }
2685 //where
2686 private Symbol choose(Symbol s1, Symbol s2) {
2687 if (lookupSuccess(s1) && lookupSuccess(s2)) {
2688 return ambiguityError(s1, s2);
2689 } else if (lookupSuccess(s1) ||
2690 (canIgnore(s2) && !canIgnore(s1))) {
2691 return s1;
2692 } else if (lookupSuccess(s2) ||
2693 (canIgnore(s1) && !canIgnore(s2))) {
2694 return s2;
2695 } else {
2696 return s1;
2697 }
2698 }
2700 private boolean lookupSuccess(Symbol s) {
2701 return s.kind == MTH || s.kind == AMBIGUOUS;
2702 }
2704 private boolean canIgnore(Symbol s) {
2705 switch (s.kind) {
2706 case ABSENT_MTH:
2707 return true;
2708 case WRONG_MTH:
2709 InapplicableSymbolError errSym =
2710 (InapplicableSymbolError)s;
2711 return new Template(MethodCheckDiag.ARITY_MISMATCH.regex())
2712 .matches(errSym.errCandidate().snd);
2713 case WRONG_MTHS:
2714 InapplicableSymbolsError errSyms =
2715 (InapplicableSymbolsError)s;
2716 return errSyms.filterCandidates(errSyms.mapCandidates()).isEmpty();
2717 default:
2718 return false;
2719 }
2720 }
2722 /**
2723 * Helper for defining custom method-like lookup logic; a lookup helper
2724 * provides hooks for (i) the actual lookup logic and (ii) accessing the
2725 * lookup result (this step might result in compiler diagnostics to be generated)
2726 */
2727 abstract class LookupHelper {
2729 /** name of the symbol to lookup */
2730 Name name;
2732 /** location in which the lookup takes place */
2733 Type site;
2735 /** actual types used during the lookup */
2736 List<Type> argtypes;
2738 /** type arguments used during the lookup */
2739 List<Type> typeargtypes;
2741 /** Max overload resolution phase handled by this helper */
2742 MethodResolutionPhase maxPhase;
2744 LookupHelper(Name name, Type site, List<Type> argtypes, List<Type> typeargtypes, MethodResolutionPhase maxPhase) {
2745 this.name = name;
2746 this.site = site;
2747 this.argtypes = argtypes;
2748 this.typeargtypes = typeargtypes;
2749 this.maxPhase = maxPhase;
2750 }
2752 /**
2753 * Should lookup stop at given phase with given result
2754 */
2755 protected boolean shouldStop(Symbol sym, MethodResolutionPhase phase) {
2756 return phase.ordinal() > maxPhase.ordinal() ||
2757 sym.kind < ERRONEOUS || sym.kind == AMBIGUOUS;
2758 }
2760 /**
2761 * Search for a symbol under a given overload resolution phase - this method
2762 * is usually called several times, once per each overload resolution phase
2763 */
2764 abstract Symbol lookup(Env<AttrContext> env, MethodResolutionPhase phase);
2766 /**
2767 * Dump overload resolution info
2768 */
2769 void debug(DiagnosticPosition pos, Symbol sym) {
2770 //do nothing
2771 }
2773 /**
2774 * Validate the result of the lookup
2775 */
2776 abstract Symbol access(Env<AttrContext> env, DiagnosticPosition pos, Symbol location, Symbol sym);
2777 }
2779 abstract class BasicLookupHelper extends LookupHelper {
2781 BasicLookupHelper(Name name, Type site, List<Type> argtypes, List<Type> typeargtypes) {
2782 this(name, site, argtypes, typeargtypes, MethodResolutionPhase.VARARITY);
2783 }
2785 BasicLookupHelper(Name name, Type site, List<Type> argtypes, List<Type> typeargtypes, MethodResolutionPhase maxPhase) {
2786 super(name, site, argtypes, typeargtypes, maxPhase);
2787 }
2789 @Override
2790 final Symbol lookup(Env<AttrContext> env, MethodResolutionPhase phase) {
2791 Symbol sym = doLookup(env, phase);
2792 if (sym.kind == AMBIGUOUS) {
2793 AmbiguityError a_err = (AmbiguityError)sym;
2794 sym = a_err.mergeAbstracts(site);
2795 }
2796 return sym;
2797 }
2799 abstract Symbol doLookup(Env<AttrContext> env, MethodResolutionPhase phase);
2801 @Override
2802 Symbol access(Env<AttrContext> env, DiagnosticPosition pos, Symbol location, Symbol sym) {
2803 if (sym.kind >= AMBIGUOUS) {
2804 //if nothing is found return the 'first' error
2805 sym = accessMethod(sym, pos, location, site, name, true, argtypes, typeargtypes);
2806 }
2807 return sym;
2808 }
2810 @Override
2811 void debug(DiagnosticPosition pos, Symbol sym) {
2812 reportVerboseResolutionDiagnostic(pos, name, site, argtypes, typeargtypes, sym);
2813 }
2814 }
2816 /**
2817 * Helper class for member reference lookup. A reference lookup helper
2818 * defines the basic logic for member reference lookup; a method gives
2819 * access to an 'unbound' helper used to perform an unbound member
2820 * reference lookup.
2821 */
2822 abstract class ReferenceLookupHelper extends LookupHelper {
2824 /** The member reference tree */
2825 JCMemberReference referenceTree;
2827 ReferenceLookupHelper(JCMemberReference referenceTree, Name name, Type site,
2828 List<Type> argtypes, List<Type> typeargtypes, MethodResolutionPhase maxPhase) {
2829 super(name, site, argtypes, typeargtypes, maxPhase);
2830 this.referenceTree = referenceTree;
2832 }
2834 /**
2835 * Returns an unbound version of this lookup helper. By default, this
2836 * method returns an dummy lookup helper.
2837 */
2838 ReferenceLookupHelper unboundLookup(InferenceContext inferenceContext) {
2839 //dummy loopkup helper that always return 'methodNotFound'
2840 return new ReferenceLookupHelper(referenceTree, name, site, argtypes, typeargtypes, maxPhase) {
2841 @Override
2842 ReferenceLookupHelper unboundLookup(InferenceContext inferenceContext) {
2843 return this;
2844 }
2845 @Override
2846 Symbol lookup(Env<AttrContext> env, MethodResolutionPhase phase) {
2847 return methodNotFound;
2848 }
2849 @Override
2850 ReferenceKind referenceKind(Symbol sym) {
2851 Assert.error();
2852 return null;
2853 }
2854 };
2855 }
2857 /**
2858 * Get the kind of the member reference
2859 */
2860 abstract JCMemberReference.ReferenceKind referenceKind(Symbol sym);
2862 Symbol access(Env<AttrContext> env, DiagnosticPosition pos, Symbol location, Symbol sym) {
2863 if (sym.kind == AMBIGUOUS) {
2864 AmbiguityError a_err = (AmbiguityError)sym;
2865 sym = a_err.mergeAbstracts(site);
2866 }
2867 //skip error reporting
2868 return sym;
2869 }
2870 }
2872 /**
2873 * Helper class for method reference lookup. The lookup logic is based
2874 * upon Resolve.findMethod; in certain cases, this helper class has a
2875 * corresponding unbound helper class (see UnboundMethodReferenceLookupHelper).
2876 * In such cases, non-static lookup results are thrown away.
2877 */
2878 class MethodReferenceLookupHelper extends ReferenceLookupHelper {
2880 MethodReferenceLookupHelper(JCMemberReference referenceTree, Name name, Type site,
2881 List<Type> argtypes, List<Type> typeargtypes, MethodResolutionPhase maxPhase) {
2882 super(referenceTree, name, site, argtypes, typeargtypes, maxPhase);
2883 }
2885 @Override
2886 final Symbol lookup(Env<AttrContext> env, MethodResolutionPhase phase) {
2887 return findMethod(env, site, name, argtypes, typeargtypes,
2888 phase.isBoxingRequired(), phase.isVarargsRequired(), syms.operatorNames.contains(name));
2889 }
2891 @Override
2892 ReferenceLookupHelper unboundLookup(InferenceContext inferenceContext) {
2893 if (TreeInfo.isStaticSelector(referenceTree.expr, names) &&
2894 argtypes.nonEmpty() &&
2895 (argtypes.head.hasTag(NONE) ||
2896 types.isSubtypeUnchecked(inferenceContext.asFree(argtypes.head), site))) {
2897 return new UnboundMethodReferenceLookupHelper(referenceTree, name,
2898 site, argtypes, typeargtypes, maxPhase);
2899 } else {
2900 return super.unboundLookup(inferenceContext);
2901 }
2902 }
2904 @Override
2905 ReferenceKind referenceKind(Symbol sym) {
2906 if (sym.isStatic()) {
2907 return ReferenceKind.STATIC;
2908 } else {
2909 Name selName = TreeInfo.name(referenceTree.getQualifierExpression());
2910 return selName != null && selName == names._super ?
2911 ReferenceKind.SUPER :
2912 ReferenceKind.BOUND;
2913 }
2914 }
2915 }
2917 /**
2918 * Helper class for unbound method reference lookup. Essentially the same
2919 * as the basic method reference lookup helper; main difference is that static
2920 * lookup results are thrown away. If qualifier type is raw, an attempt to
2921 * infer a parameterized type is made using the first actual argument (that
2922 * would otherwise be ignored during the lookup).
2923 */
2924 class UnboundMethodReferenceLookupHelper extends MethodReferenceLookupHelper {
2926 UnboundMethodReferenceLookupHelper(JCMemberReference referenceTree, Name name, Type site,
2927 List<Type> argtypes, List<Type> typeargtypes, MethodResolutionPhase maxPhase) {
2928 super(referenceTree, name, site, argtypes.tail, typeargtypes, maxPhase);
2929 if (site.isRaw() && !argtypes.head.hasTag(NONE)) {
2930 Type asSuperSite = types.asSuper(argtypes.head, site.tsym);
2931 this.site = asSuperSite;
2932 }
2933 }
2935 @Override
2936 ReferenceLookupHelper unboundLookup(InferenceContext inferenceContext) {
2937 return this;
2938 }
2940 @Override
2941 ReferenceKind referenceKind(Symbol sym) {
2942 return ReferenceKind.UNBOUND;
2943 }
2944 }
2946 /**
2947 * Helper class for array constructor lookup; an array constructor lookup
2948 * is simulated by looking up a method that returns the array type specified
2949 * as qualifier, and that accepts a single int parameter (size of the array).
2950 */
2951 class ArrayConstructorReferenceLookupHelper extends ReferenceLookupHelper {
2953 ArrayConstructorReferenceLookupHelper(JCMemberReference referenceTree, Type site, List<Type> argtypes,
2954 List<Type> typeargtypes, MethodResolutionPhase maxPhase) {
2955 super(referenceTree, names.init, site, argtypes, typeargtypes, maxPhase);
2956 }
2958 @Override
2959 protected Symbol lookup(Env<AttrContext> env, MethodResolutionPhase phase) {
2960 Scope sc = new Scope(syms.arrayClass);
2961 MethodSymbol arrayConstr = new MethodSymbol(PUBLIC, name, null, site.tsym);
2962 arrayConstr.type = new MethodType(List.<Type>of(syms.intType), site, List.<Type>nil(), syms.methodClass);
2963 sc.enter(arrayConstr);
2964 return findMethodInScope(env, site, name, argtypes, typeargtypes, sc, methodNotFound, phase.isBoxingRequired(), phase.isVarargsRequired(), false, false);
2965 }
2967 @Override
2968 ReferenceKind referenceKind(Symbol sym) {
2969 return ReferenceKind.ARRAY_CTOR;
2970 }
2971 }
2973 /**
2974 * Helper class for constructor reference lookup. The lookup logic is based
2975 * upon either Resolve.findMethod or Resolve.findDiamond - depending on
2976 * whether the constructor reference needs diamond inference (this is the case
2977 * if the qualifier type is raw). A special erroneous symbol is returned
2978 * if the lookup returns the constructor of an inner class and there's no
2979 * enclosing instance in scope.
2980 */
2981 class ConstructorReferenceLookupHelper extends ReferenceLookupHelper {
2983 boolean needsInference;
2985 ConstructorReferenceLookupHelper(JCMemberReference referenceTree, Type site, List<Type> argtypes,
2986 List<Type> typeargtypes, MethodResolutionPhase maxPhase) {
2987 super(referenceTree, names.init, site, argtypes, typeargtypes, maxPhase);
2988 if (site.isRaw()) {
2989 this.site = new ClassType(site.getEnclosingType(), site.tsym.type.getTypeArguments(), site.tsym);
2990 needsInference = true;
2991 }
2992 }
2994 @Override
2995 protected Symbol lookup(Env<AttrContext> env, MethodResolutionPhase phase) {
2996 Symbol sym = needsInference ?
2997 findDiamond(env, site, argtypes, typeargtypes, phase.isBoxingRequired(), phase.isVarargsRequired()) :
2998 findMethod(env, site, name, argtypes, typeargtypes,
2999 phase.isBoxingRequired(), phase.isVarargsRequired(), syms.operatorNames.contains(name));
3000 return sym.kind != MTH ||
3001 site.getEnclosingType().hasTag(NONE) ||
3002 hasEnclosingInstance(env, site) ?
3003 sym : new InvalidSymbolError(Kinds.MISSING_ENCL, sym, null) {
3004 @Override
3005 JCDiagnostic getDiagnostic(DiagnosticType dkind, DiagnosticPosition pos, Symbol location, Type site, Name name, List<Type> argtypes, List<Type> typeargtypes) {
3006 return diags.create(dkind, log.currentSource(), pos,
3007 "cant.access.inner.cls.constr", site.tsym.name, argtypes, site.getEnclosingType());
3008 }
3009 };
3010 }
3012 @Override
3013 ReferenceKind referenceKind(Symbol sym) {
3014 return site.getEnclosingType().hasTag(NONE) ?
3015 ReferenceKind.TOPLEVEL : ReferenceKind.IMPLICIT_INNER;
3016 }
3017 }
3019 /**
3020 * Main overload resolution routine. On each overload resolution step, a
3021 * lookup helper class is used to perform the method/constructor lookup;
3022 * at the end of the lookup, the helper is used to validate the results
3023 * (this last step might trigger overload resolution diagnostics).
3024 */
3025 Symbol lookupMethod(Env<AttrContext> env, DiagnosticPosition pos, Symbol location, MethodCheck methodCheck, LookupHelper lookupHelper) {
3026 MethodResolutionContext resolveContext = new MethodResolutionContext();
3027 resolveContext.methodCheck = methodCheck;
3028 return lookupMethod(env, pos, location, resolveContext, lookupHelper);
3029 }
3031 Symbol lookupMethod(Env<AttrContext> env, DiagnosticPosition pos, Symbol location,
3032 MethodResolutionContext resolveContext, LookupHelper lookupHelper) {
3033 MethodResolutionContext prevResolutionContext = currentResolutionContext;
3034 try {
3035 Symbol bestSoFar = methodNotFound;
3036 currentResolutionContext = resolveContext;
3037 for (MethodResolutionPhase phase : methodResolutionSteps) {
3038 if (!phase.isApplicable(boxingEnabled, varargsEnabled) ||
3039 lookupHelper.shouldStop(bestSoFar, phase)) break;
3040 MethodResolutionPhase prevPhase = currentResolutionContext.step;
3041 Symbol prevBest = bestSoFar;
3042 currentResolutionContext.step = phase;
3043 Symbol sym = lookupHelper.lookup(env, phase);
3044 lookupHelper.debug(pos, sym);
3045 bestSoFar = phase.mergeResults(bestSoFar, sym);
3046 env.info.pendingResolutionPhase = (prevBest == bestSoFar) ? prevPhase : phase;
3047 }
3048 return lookupHelper.access(env, pos, location, bestSoFar);
3049 } finally {
3050 currentResolutionContext = prevResolutionContext;
3051 }
3052 }
3054 /**
3055 * Resolve `c.name' where name == this or name == super.
3056 * @param pos The position to use for error reporting.
3057 * @param env The environment current at the expression.
3058 * @param c The qualifier.
3059 * @param name The identifier's name.
3060 */
3061 Symbol resolveSelf(DiagnosticPosition pos,
3062 Env<AttrContext> env,
3063 TypeSymbol c,
3064 Name name) {
3065 Env<AttrContext> env1 = env;
3066 boolean staticOnly = false;
3067 while (env1.outer != null) {
3068 if (isStatic(env1)) staticOnly = true;
3069 if (env1.enclClass.sym == c) {
3070 Symbol sym = env1.info.scope.lookup(name).sym;
3071 if (sym != null) {
3072 if (staticOnly) sym = new StaticError(sym);
3073 return accessBase(sym, pos, env.enclClass.sym.type,
3074 name, true);
3075 }
3076 }
3077 if ((env1.enclClass.sym.flags() & STATIC) != 0) staticOnly = true;
3078 env1 = env1.outer;
3079 }
3080 if (allowDefaultMethods && c.isInterface() &&
3081 name == names._super && !isStatic(env) &&
3082 types.isDirectSuperInterface(c, env.enclClass.sym)) {
3083 //this might be a default super call if one of the superinterfaces is 'c'
3084 for (Type t : pruneInterfaces(env.enclClass.type)) {
3085 if (t.tsym == c) {
3086 env.info.defaultSuperCallSite = t;
3087 return new VarSymbol(0, names._super,
3088 types.asSuper(env.enclClass.type, c), env.enclClass.sym);
3089 }
3090 }
3091 //find a direct superinterface that is a subtype of 'c'
3092 for (Type i : types.interfaces(env.enclClass.type)) {
3093 if (i.tsym.isSubClass(c, types) && i.tsym != c) {
3094 log.error(pos, "illegal.default.super.call", c,
3095 diags.fragment("redundant.supertype", c, i));
3096 return syms.errSymbol;
3097 }
3098 }
3099 Assert.error();
3100 }
3101 log.error(pos, "not.encl.class", c);
3102 return syms.errSymbol;
3103 }
3104 //where
3105 private List<Type> pruneInterfaces(Type t) {
3106 ListBuffer<Type> result = ListBuffer.lb();
3107 for (Type t1 : types.interfaces(t)) {
3108 boolean shouldAdd = true;
3109 for (Type t2 : types.interfaces(t)) {
3110 if (t1 != t2 && types.isSubtypeNoCapture(t2, t1)) {
3111 shouldAdd = false;
3112 }
3113 }
3114 if (shouldAdd) {
3115 result.append(t1);
3116 }
3117 }
3118 return result.toList();
3119 }
3122 /**
3123 * Resolve `c.this' for an enclosing class c that contains the
3124 * named member.
3125 * @param pos The position to use for error reporting.
3126 * @param env The environment current at the expression.
3127 * @param member The member that must be contained in the result.
3128 */
3129 Symbol resolveSelfContaining(DiagnosticPosition pos,
3130 Env<AttrContext> env,
3131 Symbol member,
3132 boolean isSuperCall) {
3133 Symbol sym = resolveSelfContainingInternal(env, member, isSuperCall);
3134 if (sym == null) {
3135 log.error(pos, "encl.class.required", member);
3136 return syms.errSymbol;
3137 } else {
3138 return accessBase(sym, pos, env.enclClass.sym.type, sym.name, true);
3139 }
3140 }
3142 boolean hasEnclosingInstance(Env<AttrContext> env, Type type) {
3143 Symbol encl = resolveSelfContainingInternal(env, type.tsym, false);
3144 return encl != null && encl.kind < ERRONEOUS;
3145 }
3147 private Symbol resolveSelfContainingInternal(Env<AttrContext> env,
3148 Symbol member,
3149 boolean isSuperCall) {
3150 Name name = names._this;
3151 Env<AttrContext> env1 = isSuperCall ? env.outer : env;
3152 boolean staticOnly = false;
3153 if (env1 != null) {
3154 while (env1 != null && env1.outer != null) {
3155 if (isStatic(env1)) staticOnly = true;
3156 if (env1.enclClass.sym.isSubClass(member.owner, types)) {
3157 Symbol sym = env1.info.scope.lookup(name).sym;
3158 if (sym != null) {
3159 if (staticOnly) sym = new StaticError(sym);
3160 return sym;
3161 }
3162 }
3163 if ((env1.enclClass.sym.flags() & STATIC) != 0)
3164 staticOnly = true;
3165 env1 = env1.outer;
3166 }
3167 }
3168 return null;
3169 }
3171 /**
3172 * Resolve an appropriate implicit this instance for t's container.
3173 * JLS 8.8.5.1 and 15.9.2
3174 */
3175 Type resolveImplicitThis(DiagnosticPosition pos, Env<AttrContext> env, Type t) {
3176 return resolveImplicitThis(pos, env, t, false);
3177 }
3179 Type resolveImplicitThis(DiagnosticPosition pos, Env<AttrContext> env, Type t, boolean isSuperCall) {
3180 Type thisType = (((t.tsym.owner.kind & (MTH|VAR)) != 0)
3181 ? resolveSelf(pos, env, t.getEnclosingType().tsym, names._this)
3182 : resolveSelfContaining(pos, env, t.tsym, isSuperCall)).type;
3183 if (env.info.isSelfCall && thisType.tsym == env.enclClass.sym)
3184 log.error(pos, "cant.ref.before.ctor.called", "this");
3185 return thisType;
3186 }
3188 /* ***************************************************************************
3189 * ResolveError classes, indicating error situations when accessing symbols
3190 ****************************************************************************/
3192 //used by TransTypes when checking target type of synthetic cast
3193 public void logAccessErrorInternal(Env<AttrContext> env, JCTree tree, Type type) {
3194 AccessError error = new AccessError(env, env.enclClass.type, type.tsym);
3195 logResolveError(error, tree.pos(), env.enclClass.sym, env.enclClass.type, null, null, null);
3196 }
3197 //where
3198 private void logResolveError(ResolveError error,
3199 DiagnosticPosition pos,
3200 Symbol location,
3201 Type site,
3202 Name name,
3203 List<Type> argtypes,
3204 List<Type> typeargtypes) {
3205 JCDiagnostic d = error.getDiagnostic(JCDiagnostic.DiagnosticType.ERROR,
3206 pos, location, site, name, argtypes, typeargtypes);
3207 if (d != null) {
3208 d.setFlag(DiagnosticFlag.RESOLVE_ERROR);
3209 log.report(d);
3210 }
3211 }
3213 private final LocalizedString noArgs = new LocalizedString("compiler.misc.no.args");
3215 public Object methodArguments(List<Type> argtypes) {
3216 if (argtypes == null || argtypes.isEmpty()) {
3217 return noArgs;
3218 } else {
3219 ListBuffer<Object> diagArgs = ListBuffer.lb();
3220 for (Type t : argtypes) {
3221 if (t.hasTag(DEFERRED)) {
3222 diagArgs.append(((DeferredAttr.DeferredType)t).tree);
3223 } else {
3224 diagArgs.append(t);
3225 }
3226 }
3227 return diagArgs;
3228 }
3229 }
3231 /**
3232 * Root class for resolution errors. Subclass of ResolveError
3233 * represent a different kinds of resolution error - as such they must
3234 * specify how they map into concrete compiler diagnostics.
3235 */
3236 abstract class ResolveError extends Symbol {
3238 /** The name of the kind of error, for debugging only. */
3239 final String debugName;
3241 ResolveError(int kind, String debugName) {
3242 super(kind, 0, null, null, null);
3243 this.debugName = debugName;
3244 }
3246 @Override
3247 public <R, P> R accept(ElementVisitor<R, P> v, P p) {
3248 throw new AssertionError();
3249 }
3251 @Override
3252 public String toString() {
3253 return debugName;
3254 }
3256 @Override
3257 public boolean exists() {
3258 return false;
3259 }
3261 /**
3262 * Create an external representation for this erroneous symbol to be
3263 * used during attribution - by default this returns the symbol of a
3264 * brand new error type which stores the original type found
3265 * during resolution.
3266 *
3267 * @param name the name used during resolution
3268 * @param location the location from which the symbol is accessed
3269 */
3270 protected Symbol access(Name name, TypeSymbol location) {
3271 return types.createErrorType(name, location, syms.errSymbol.type).tsym;
3272 }
3274 /**
3275 * Create a diagnostic representing this resolution error.
3276 *
3277 * @param dkind The kind of the diagnostic to be created (e.g error).
3278 * @param pos The position to be used for error reporting.
3279 * @param site The original type from where the selection took place.
3280 * @param name The name of the symbol to be resolved.
3281 * @param argtypes The invocation's value arguments,
3282 * if we looked for a method.
3283 * @param typeargtypes The invocation's type arguments,
3284 * if we looked for a method.
3285 */
3286 abstract JCDiagnostic getDiagnostic(JCDiagnostic.DiagnosticType dkind,
3287 DiagnosticPosition pos,
3288 Symbol location,
3289 Type site,
3290 Name name,
3291 List<Type> argtypes,
3292 List<Type> typeargtypes);
3293 }
3295 /**
3296 * This class is the root class of all resolution errors caused by
3297 * an invalid symbol being found during resolution.
3298 */
3299 abstract class InvalidSymbolError extends ResolveError {
3301 /** The invalid symbol found during resolution */
3302 Symbol sym;
3304 InvalidSymbolError(int kind, Symbol sym, String debugName) {
3305 super(kind, debugName);
3306 this.sym = sym;
3307 }
3309 @Override
3310 public boolean exists() {
3311 return true;
3312 }
3314 @Override
3315 public String toString() {
3316 return super.toString() + " wrongSym=" + sym;
3317 }
3319 @Override
3320 public Symbol access(Name name, TypeSymbol location) {
3321 if ((sym.kind & ERRONEOUS) == 0 && (sym.kind & TYP) != 0)
3322 return types.createErrorType(name, location, sym.type).tsym;
3323 else
3324 return sym;
3325 }
3326 }
3328 /**
3329 * InvalidSymbolError error class indicating that a symbol matching a
3330 * given name does not exists in a given site.
3331 */
3332 class SymbolNotFoundError extends ResolveError {
3334 SymbolNotFoundError(int kind) {
3335 super(kind, "symbol not found error");
3336 }
3338 @Override
3339 JCDiagnostic getDiagnostic(JCDiagnostic.DiagnosticType dkind,
3340 DiagnosticPosition pos,
3341 Symbol location,
3342 Type site,
3343 Name name,
3344 List<Type> argtypes,
3345 List<Type> typeargtypes) {
3346 argtypes = argtypes == null ? List.<Type>nil() : argtypes;
3347 typeargtypes = typeargtypes == null ? List.<Type>nil() : typeargtypes;
3348 if (name == names.error)
3349 return null;
3351 if (syms.operatorNames.contains(name)) {
3352 boolean isUnaryOp = argtypes.size() == 1;
3353 String key = argtypes.size() == 1 ?
3354 "operator.cant.be.applied" :
3355 "operator.cant.be.applied.1";
3356 Type first = argtypes.head;
3357 Type second = !isUnaryOp ? argtypes.tail.head : null;
3358 return diags.create(dkind, log.currentSource(), pos,
3359 key, name, first, second);
3360 }
3361 boolean hasLocation = false;
3362 if (location == null) {
3363 location = site.tsym;
3364 }
3365 if (!location.name.isEmpty()) {
3366 if (location.kind == PCK && !site.tsym.exists()) {
3367 return diags.create(dkind, log.currentSource(), pos,
3368 "doesnt.exist", location);
3369 }
3370 hasLocation = !location.name.equals(names._this) &&
3371 !location.name.equals(names._super);
3372 }
3373 boolean isConstructor = kind == ABSENT_MTH && name == names.init;
3374 KindName kindname = isConstructor ? KindName.CONSTRUCTOR : absentKind(kind);
3375 Name idname = isConstructor ? site.tsym.name : name;
3376 String errKey = getErrorKey(kindname, typeargtypes.nonEmpty(), hasLocation);
3377 if (hasLocation) {
3378 return diags.create(dkind, log.currentSource(), pos,
3379 errKey, kindname, idname, //symbol kindname, name
3380 typeargtypes, args(argtypes), //type parameters and arguments (if any)
3381 getLocationDiag(location, site)); //location kindname, type
3382 }
3383 else {
3384 return diags.create(dkind, log.currentSource(), pos,
3385 errKey, kindname, idname, //symbol kindname, name
3386 typeargtypes, args(argtypes)); //type parameters and arguments (if any)
3387 }
3388 }
3389 //where
3390 private Object args(List<Type> args) {
3391 return args.isEmpty() ? args : methodArguments(args);
3392 }
3394 private String getErrorKey(KindName kindname, boolean hasTypeArgs, boolean hasLocation) {
3395 String key = "cant.resolve";
3396 String suffix = hasLocation ? ".location" : "";
3397 switch (kindname) {
3398 case METHOD:
3399 case CONSTRUCTOR: {
3400 suffix += ".args";
3401 suffix += hasTypeArgs ? ".params" : "";
3402 }
3403 }
3404 return key + suffix;
3405 }
3406 private JCDiagnostic getLocationDiag(Symbol location, Type site) {
3407 if (location.kind == VAR) {
3408 return diags.fragment("location.1",
3409 kindName(location),
3410 location,
3411 location.type);
3412 } else {
3413 return diags.fragment("location",
3414 typeKindName(site),
3415 site,
3416 null);
3417 }
3418 }
3419 }
3421 /**
3422 * InvalidSymbolError error class indicating that a given symbol
3423 * (either a method, a constructor or an operand) is not applicable
3424 * given an actual arguments/type argument list.
3425 */
3426 class InapplicableSymbolError extends ResolveError {
3428 protected MethodResolutionContext resolveContext;
3430 InapplicableSymbolError(MethodResolutionContext context) {
3431 this(WRONG_MTH, "inapplicable symbol error", context);
3432 }
3434 protected InapplicableSymbolError(int kind, String debugName, MethodResolutionContext context) {
3435 super(kind, debugName);
3436 this.resolveContext = context;
3437 }
3439 @Override
3440 public String toString() {
3441 return super.toString();
3442 }
3444 @Override
3445 public boolean exists() {
3446 return true;
3447 }
3449 @Override
3450 JCDiagnostic getDiagnostic(JCDiagnostic.DiagnosticType dkind,
3451 DiagnosticPosition pos,
3452 Symbol location,
3453 Type site,
3454 Name name,
3455 List<Type> argtypes,
3456 List<Type> typeargtypes) {
3457 if (name == names.error)
3458 return null;
3460 if (syms.operatorNames.contains(name)) {
3461 boolean isUnaryOp = argtypes.size() == 1;
3462 String key = argtypes.size() == 1 ?
3463 "operator.cant.be.applied" :
3464 "operator.cant.be.applied.1";
3465 Type first = argtypes.head;
3466 Type second = !isUnaryOp ? argtypes.tail.head : null;
3467 return diags.create(dkind, log.currentSource(), pos,
3468 key, name, first, second);
3469 }
3470 else {
3471 Pair<Symbol, JCDiagnostic> c = errCandidate();
3472 if (compactMethodDiags) {
3473 for (Map.Entry<Template, DiagnosticRewriter> _entry :
3474 MethodResolutionDiagHelper.rewriters.entrySet()) {
3475 if (_entry.getKey().matches(c.snd)) {
3476 JCDiagnostic simpleDiag =
3477 _entry.getValue().rewriteDiagnostic(diags, pos,
3478 log.currentSource(), dkind, c.snd);
3479 simpleDiag.setFlag(DiagnosticFlag.COMPRESSED);
3480 return simpleDiag;
3481 }
3482 }
3483 }
3484 Symbol ws = c.fst.asMemberOf(site, types);
3485 return diags.create(dkind, log.currentSource(), pos,
3486 "cant.apply.symbol",
3487 kindName(ws),
3488 ws.name == names.init ? ws.owner.name : ws.name,
3489 methodArguments(ws.type.getParameterTypes()),
3490 methodArguments(argtypes),
3491 kindName(ws.owner),
3492 ws.owner.type,
3493 c.snd);
3494 }
3495 }
3497 @Override
3498 public Symbol access(Name name, TypeSymbol location) {
3499 return types.createErrorType(name, location, syms.errSymbol.type).tsym;
3500 }
3502 protected Pair<Symbol, JCDiagnostic> errCandidate() {
3503 Candidate bestSoFar = null;
3504 for (Candidate c : resolveContext.candidates) {
3505 if (c.isApplicable()) continue;
3506 bestSoFar = c;
3507 }
3508 Assert.checkNonNull(bestSoFar);
3509 return new Pair<Symbol, JCDiagnostic>(bestSoFar.sym, bestSoFar.details);
3510 }
3511 }
3513 /**
3514 * ResolveError error class indicating that a set of symbols
3515 * (either methods, constructors or operands) is not applicable
3516 * given an actual arguments/type argument list.
3517 */
3518 class InapplicableSymbolsError extends InapplicableSymbolError {
3520 InapplicableSymbolsError(MethodResolutionContext context) {
3521 super(WRONG_MTHS, "inapplicable symbols", context);
3522 }
3524 @Override
3525 JCDiagnostic getDiagnostic(JCDiagnostic.DiagnosticType dkind,
3526 DiagnosticPosition pos,
3527 Symbol location,
3528 Type site,
3529 Name name,
3530 List<Type> argtypes,
3531 List<Type> typeargtypes) {
3532 Map<Symbol, JCDiagnostic> candidatesMap = mapCandidates();
3533 Map<Symbol, JCDiagnostic> filteredCandidates = compactMethodDiags ?
3534 filterCandidates(candidatesMap) :
3535 mapCandidates();
3536 if (filteredCandidates.isEmpty()) {
3537 filteredCandidates = candidatesMap;
3538 }
3539 boolean truncatedDiag = candidatesMap.size() != filteredCandidates.size();
3540 if (filteredCandidates.size() > 1) {
3541 JCDiagnostic err = diags.create(dkind,
3542 null,
3543 truncatedDiag ?
3544 EnumSet.of(DiagnosticFlag.COMPRESSED) :
3545 EnumSet.noneOf(DiagnosticFlag.class),
3546 log.currentSource(),
3547 pos,
3548 "cant.apply.symbols",
3549 name == names.init ? KindName.CONSTRUCTOR : absentKind(kind),
3550 name == names.init ? site.tsym.name : name,
3551 methodArguments(argtypes));
3552 return new JCDiagnostic.MultilineDiagnostic(err, candidateDetails(filteredCandidates, site));
3553 } else if (filteredCandidates.size() == 1) {
3554 Map.Entry<Symbol, JCDiagnostic> _e =
3555 filteredCandidates.entrySet().iterator().next();
3556 final Pair<Symbol, JCDiagnostic> p = new Pair<Symbol, JCDiagnostic>(_e.getKey(), _e.getValue());
3557 JCDiagnostic d = new InapplicableSymbolError(resolveContext) {
3558 @Override
3559 protected Pair<Symbol, JCDiagnostic> errCandidate() {
3560 return p;
3561 }
3562 }.getDiagnostic(dkind, pos,
3563 location, site, name, argtypes, typeargtypes);
3564 if (truncatedDiag) {
3565 d.setFlag(DiagnosticFlag.COMPRESSED);
3566 }
3567 return d;
3568 } else {
3569 return new SymbolNotFoundError(ABSENT_MTH).getDiagnostic(dkind, pos,
3570 location, site, name, argtypes, typeargtypes);
3571 }
3572 }
3573 //where
3574 private Map<Symbol, JCDiagnostic> mapCandidates() {
3575 Map<Symbol, JCDiagnostic> candidates = new LinkedHashMap<Symbol, JCDiagnostic>();
3576 for (Candidate c : resolveContext.candidates) {
3577 if (c.isApplicable()) continue;
3578 candidates.put(c.sym, c.details);
3579 }
3580 return candidates;
3581 }
3583 Map<Symbol, JCDiagnostic> filterCandidates(Map<Symbol, JCDiagnostic> candidatesMap) {
3584 Map<Symbol, JCDiagnostic> candidates = new LinkedHashMap<Symbol, JCDiagnostic>();
3585 for (Map.Entry<Symbol, JCDiagnostic> _entry : candidatesMap.entrySet()) {
3586 JCDiagnostic d = _entry.getValue();
3587 if (!new Template(MethodCheckDiag.ARITY_MISMATCH.regex()).matches(d)) {
3588 candidates.put(_entry.getKey(), d);
3589 }
3590 }
3591 return candidates;
3592 }
3594 private List<JCDiagnostic> candidateDetails(Map<Symbol, JCDiagnostic> candidatesMap, Type site) {
3595 List<JCDiagnostic> details = List.nil();
3596 for (Map.Entry<Symbol, JCDiagnostic> _entry : candidatesMap.entrySet()) {
3597 Symbol sym = _entry.getKey();
3598 JCDiagnostic detailDiag = diags.fragment("inapplicable.method",
3599 Kinds.kindName(sym),
3600 sym.location(site, types),
3601 sym.asMemberOf(site, types),
3602 _entry.getValue());
3603 details = details.prepend(detailDiag);
3604 }
3605 //typically members are visited in reverse order (see Scope)
3606 //so we need to reverse the candidate list so that candidates
3607 //conform to source order
3608 return details;
3609 }
3610 }
3612 /**
3613 * An InvalidSymbolError error class indicating that a symbol is not
3614 * accessible from a given site
3615 */
3616 class AccessError extends InvalidSymbolError {
3618 private Env<AttrContext> env;
3619 private Type site;
3621 AccessError(Symbol sym) {
3622 this(null, null, sym);
3623 }
3625 AccessError(Env<AttrContext> env, Type site, Symbol sym) {
3626 super(HIDDEN, sym, "access error");
3627 this.env = env;
3628 this.site = site;
3629 if (debugResolve)
3630 log.error("proc.messager", sym + " @ " + site + " is inaccessible.");
3631 }
3633 @Override
3634 public boolean exists() {
3635 return false;
3636 }
3638 @Override
3639 JCDiagnostic getDiagnostic(JCDiagnostic.DiagnosticType dkind,
3640 DiagnosticPosition pos,
3641 Symbol location,
3642 Type site,
3643 Name name,
3644 List<Type> argtypes,
3645 List<Type> typeargtypes) {
3646 if (sym.owner.type.hasTag(ERROR))
3647 return null;
3649 if (sym.name == names.init && sym.owner != site.tsym) {
3650 return new SymbolNotFoundError(ABSENT_MTH).getDiagnostic(dkind,
3651 pos, location, site, name, argtypes, typeargtypes);
3652 }
3653 else if ((sym.flags() & PUBLIC) != 0
3654 || (env != null && this.site != null
3655 && !isAccessible(env, this.site))) {
3656 return diags.create(dkind, log.currentSource(),
3657 pos, "not.def.access.class.intf.cant.access",
3658 sym, sym.location());
3659 }
3660 else if ((sym.flags() & (PRIVATE | PROTECTED)) != 0) {
3661 return diags.create(dkind, log.currentSource(),
3662 pos, "report.access", sym,
3663 asFlagSet(sym.flags() & (PRIVATE | PROTECTED)),
3664 sym.location());
3665 }
3666 else {
3667 return diags.create(dkind, log.currentSource(),
3668 pos, "not.def.public.cant.access", sym, sym.location());
3669 }
3670 }
3671 }
3673 /**
3674 * InvalidSymbolError error class indicating that an instance member
3675 * has erroneously been accessed from a static context.
3676 */
3677 class StaticError extends InvalidSymbolError {
3679 StaticError(Symbol sym) {
3680 super(STATICERR, sym, "static error");
3681 }
3683 @Override
3684 JCDiagnostic getDiagnostic(JCDiagnostic.DiagnosticType dkind,
3685 DiagnosticPosition pos,
3686 Symbol location,
3687 Type site,
3688 Name name,
3689 List<Type> argtypes,
3690 List<Type> typeargtypes) {
3691 Symbol errSym = ((sym.kind == TYP && sym.type.hasTag(CLASS))
3692 ? types.erasure(sym.type).tsym
3693 : sym);
3694 return diags.create(dkind, log.currentSource(), pos,
3695 "non-static.cant.be.ref", kindName(sym), errSym);
3696 }
3697 }
3699 /**
3700 * InvalidSymbolError error class indicating that a pair of symbols
3701 * (either methods, constructors or operands) are ambiguous
3702 * given an actual arguments/type argument list.
3703 */
3704 class AmbiguityError extends ResolveError {
3706 /** The other maximally specific symbol */
3707 List<Symbol> ambiguousSyms = List.nil();
3709 @Override
3710 public boolean exists() {
3711 return true;
3712 }
3714 AmbiguityError(Symbol sym1, Symbol sym2) {
3715 super(AMBIGUOUS, "ambiguity error");
3716 ambiguousSyms = flatten(sym2).appendList(flatten(sym1));
3717 }
3719 private List<Symbol> flatten(Symbol sym) {
3720 if (sym.kind == AMBIGUOUS) {
3721 return ((AmbiguityError)sym).ambiguousSyms;
3722 } else {
3723 return List.of(sym);
3724 }
3725 }
3727 AmbiguityError addAmbiguousSymbol(Symbol s) {
3728 ambiguousSyms = ambiguousSyms.prepend(s);
3729 return this;
3730 }
3732 @Override
3733 JCDiagnostic getDiagnostic(JCDiagnostic.DiagnosticType dkind,
3734 DiagnosticPosition pos,
3735 Symbol location,
3736 Type site,
3737 Name name,
3738 List<Type> argtypes,
3739 List<Type> typeargtypes) {
3740 List<Symbol> diagSyms = ambiguousSyms.reverse();
3741 Symbol s1 = diagSyms.head;
3742 Symbol s2 = diagSyms.tail.head;
3743 Name sname = s1.name;
3744 if (sname == names.init) sname = s1.owner.name;
3745 return diags.create(dkind, log.currentSource(),
3746 pos, "ref.ambiguous", sname,
3747 kindName(s1),
3748 s1,
3749 s1.location(site, types),
3750 kindName(s2),
3751 s2,
3752 s2.location(site, types));
3753 }
3755 /**
3756 * If multiple applicable methods are found during overload and none of them
3757 * is more specific than the others, attempt to merge their signatures.
3758 */
3759 Symbol mergeAbstracts(Type site) {
3760 List<Symbol> ambiguousInOrder = ambiguousSyms.reverse();
3761 for (Symbol s : ambiguousInOrder) {
3762 Type mt = types.memberType(site, s);
3763 boolean found = true;
3764 List<Type> allThrown = mt.getThrownTypes();
3765 for (Symbol s2 : ambiguousInOrder) {
3766 Type mt2 = types.memberType(site, s2);
3767 if ((s2.flags() & ABSTRACT) == 0 ||
3768 !types.overrideEquivalent(mt, mt2) ||
3769 !types.isSameTypes(s.erasure(types).getParameterTypes(),
3770 s2.erasure(types).getParameterTypes())) {
3771 //ambiguity cannot be resolved
3772 return this;
3773 }
3774 Type mst = mostSpecificReturnType(mt, mt2);
3775 if (mst == null || mst != mt) {
3776 found = false;
3777 break;
3778 }
3779 allThrown = chk.intersect(allThrown, mt2.getThrownTypes());
3780 }
3781 if (found) {
3782 //all ambiguous methods were abstract and one method had
3783 //most specific return type then others
3784 return (allThrown == mt.getThrownTypes()) ?
3785 s : new MethodSymbol(
3786 s.flags(),
3787 s.name,
3788 types.createMethodTypeWithThrown(mt, allThrown),
3789 s.owner);
3790 }
3791 }
3792 return this;
3793 }
3795 @Override
3796 protected Symbol access(Name name, TypeSymbol location) {
3797 Symbol firstAmbiguity = ambiguousSyms.last();
3798 return firstAmbiguity.kind == TYP ?
3799 types.createErrorType(name, location, firstAmbiguity.type).tsym :
3800 firstAmbiguity;
3801 }
3802 }
3804 class BadVarargsMethod extends ResolveError {
3806 ResolveError delegatedError;
3808 BadVarargsMethod(ResolveError delegatedError) {
3809 super(delegatedError.kind, "badVarargs");
3810 this.delegatedError = delegatedError;
3811 }
3813 @Override
3814 public Symbol baseSymbol() {
3815 return delegatedError.baseSymbol();
3816 }
3818 @Override
3819 protected Symbol access(Name name, TypeSymbol location) {
3820 return delegatedError.access(name, location);
3821 }
3823 @Override
3824 public boolean exists() {
3825 return true;
3826 }
3828 @Override
3829 JCDiagnostic getDiagnostic(DiagnosticType dkind, DiagnosticPosition pos, Symbol location, Type site, Name name, List<Type> argtypes, List<Type> typeargtypes) {
3830 return delegatedError.getDiagnostic(dkind, pos, location, site, name, argtypes, typeargtypes);
3831 }
3832 }
3834 /**
3835 * Helper class for method resolution diagnostic simplification.
3836 * Certain resolution diagnostic are rewritten as simpler diagnostic
3837 * where the enclosing resolution diagnostic (i.e. 'inapplicable method')
3838 * is stripped away, as it doesn't carry additional info. The logic
3839 * for matching a given diagnostic is given in terms of a template
3840 * hierarchy: a diagnostic template can be specified programmatically,
3841 * so that only certain diagnostics are matched. Each templete is then
3842 * associated with a rewriter object that carries out the task of rewtiting
3843 * the diagnostic to a simpler one.
3844 */
3845 static class MethodResolutionDiagHelper {
3847 /**
3848 * A diagnostic rewriter transforms a method resolution diagnostic
3849 * into a simpler one
3850 */
3851 interface DiagnosticRewriter {
3852 JCDiagnostic rewriteDiagnostic(JCDiagnostic.Factory diags,
3853 DiagnosticPosition preferedPos, DiagnosticSource preferredSource,
3854 DiagnosticType preferredKind, JCDiagnostic d);
3855 }
3857 /**
3858 * A diagnostic template is made up of two ingredients: (i) a regular
3859 * expression for matching a diagnostic key and (ii) a list of sub-templates
3860 * for matching diagnostic arguments.
3861 */
3862 static class Template {
3864 /** regex used to match diag key */
3865 String regex;
3867 /** templates used to match diagnostic args */
3868 Template[] subTemplates;
3870 Template(String key, Template... subTemplates) {
3871 this.regex = key;
3872 this.subTemplates = subTemplates;
3873 }
3875 /**
3876 * Returns true if the regex matches the diagnostic key and if
3877 * all diagnostic arguments are matches by corresponding sub-templates.
3878 */
3879 boolean matches(Object o) {
3880 JCDiagnostic d = (JCDiagnostic)o;
3881 Object[] args = d.getArgs();
3882 if (!d.getCode().matches(regex) ||
3883 subTemplates.length != d.getArgs().length) {
3884 return false;
3885 }
3886 for (int i = 0; i < args.length ; i++) {
3887 if (!subTemplates[i].matches(args[i])) {
3888 return false;
3889 }
3890 }
3891 return true;
3892 }
3893 }
3895 /** a dummy template that match any diagnostic argument */
3896 static final Template skip = new Template("") {
3897 @Override
3898 boolean matches(Object d) {
3899 return true;
3900 }
3901 };
3903 /** rewriter map used for method resolution simplification */
3904 static final Map<Template, DiagnosticRewriter> rewriters =
3905 new LinkedHashMap<Template, DiagnosticRewriter>();
3907 static {
3908 String argMismatchRegex = MethodCheckDiag.ARG_MISMATCH.regex();
3909 rewriters.put(new Template(argMismatchRegex, new Template("(.*)(bad.arg.types.in.lambda)", skip, skip)),
3910 new DiagnosticRewriter() {
3911 @Override
3912 public JCDiagnostic rewriteDiagnostic(JCDiagnostic.Factory diags,
3913 DiagnosticPosition preferedPos, DiagnosticSource preferredSource,
3914 DiagnosticType preferredKind, JCDiagnostic d) {
3915 return (JCDiagnostic)((JCDiagnostic)d.getArgs()[0]).getArgs()[1];
3916 }
3917 });
3919 rewriters.put(new Template(argMismatchRegex, skip),
3920 new DiagnosticRewriter() {
3921 @Override
3922 public JCDiagnostic rewriteDiagnostic(JCDiagnostic.Factory diags,
3923 DiagnosticPosition preferedPos, DiagnosticSource preferredSource,
3924 DiagnosticType preferredKind, JCDiagnostic d) {
3925 JCDiagnostic cause = (JCDiagnostic)d.getArgs()[0];
3926 return diags.create(preferredKind, preferredSource, d.getDiagnosticPosition(),
3927 "prob.found.req", cause);
3928 }
3929 });
3930 }
3931 }
3933 enum MethodResolutionPhase {
3934 BASIC(false, false),
3935 BOX(true, false),
3936 VARARITY(true, true) {
3937 @Override
3938 public Symbol mergeResults(Symbol bestSoFar, Symbol sym) {
3939 switch (sym.kind) {
3940 case WRONG_MTH:
3941 return (bestSoFar.kind == WRONG_MTH || bestSoFar.kind == WRONG_MTHS) ?
3942 bestSoFar :
3943 sym;
3944 case ABSENT_MTH:
3945 return bestSoFar;
3946 default:
3947 return sym;
3948 }
3949 }
3950 };
3952 final boolean isBoxingRequired;
3953 final boolean isVarargsRequired;
3955 MethodResolutionPhase(boolean isBoxingRequired, boolean isVarargsRequired) {
3956 this.isBoxingRequired = isBoxingRequired;
3957 this.isVarargsRequired = isVarargsRequired;
3958 }
3960 public boolean isBoxingRequired() {
3961 return isBoxingRequired;
3962 }
3964 public boolean isVarargsRequired() {
3965 return isVarargsRequired;
3966 }
3968 public boolean isApplicable(boolean boxingEnabled, boolean varargsEnabled) {
3969 return (varargsEnabled || !isVarargsRequired) &&
3970 (boxingEnabled || !isBoxingRequired);
3971 }
3973 public Symbol mergeResults(Symbol prev, Symbol sym) {
3974 return sym;
3975 }
3976 }
3978 final List<MethodResolutionPhase> methodResolutionSteps = List.of(BASIC, BOX, VARARITY);
3980 /**
3981 * A resolution context is used to keep track of intermediate results of
3982 * overload resolution, such as list of method that are not applicable
3983 * (used to generate more precise diagnostics) and so on. Resolution contexts
3984 * can be nested - this means that when each overload resolution routine should
3985 * work within the resolution context it created.
3986 */
3987 class MethodResolutionContext {
3989 private List<Candidate> candidates = List.nil();
3991 MethodResolutionPhase step = null;
3993 MethodCheck methodCheck = resolveMethodCheck;
3995 private boolean internalResolution = false;
3996 private DeferredAttr.AttrMode attrMode = DeferredAttr.AttrMode.SPECULATIVE;
3998 void addInapplicableCandidate(Symbol sym, JCDiagnostic details) {
3999 Candidate c = new Candidate(currentResolutionContext.step, sym, details, null);
4000 candidates = candidates.append(c);
4001 }
4003 void addApplicableCandidate(Symbol sym, Type mtype) {
4004 Candidate c = new Candidate(currentResolutionContext.step, sym, null, mtype);
4005 candidates = candidates.append(c);
4006 }
4008 DeferredAttrContext deferredAttrContext(Symbol sym, InferenceContext inferenceContext, ResultInfo pendingResult, Warner warn) {
4009 return deferredAttr.new DeferredAttrContext(attrMode, sym, step, inferenceContext, pendingResult != null ? pendingResult.checkContext.deferredAttrContext() : deferredAttr.emptyDeferredAttrContext, warn);
4010 }
4012 /**
4013 * This class represents an overload resolution candidate. There are two
4014 * kinds of candidates: applicable methods and inapplicable methods;
4015 * applicable methods have a pointer to the instantiated method type,
4016 * while inapplicable candidates contain further details about the
4017 * reason why the method has been considered inapplicable.
4018 */
4019 @SuppressWarnings("overrides")
4020 class Candidate {
4022 final MethodResolutionPhase step;
4023 final Symbol sym;
4024 final JCDiagnostic details;
4025 final Type mtype;
4027 private Candidate(MethodResolutionPhase step, Symbol sym, JCDiagnostic details, Type mtype) {
4028 this.step = step;
4029 this.sym = sym;
4030 this.details = details;
4031 this.mtype = mtype;
4032 }
4034 @Override
4035 public boolean equals(Object o) {
4036 if (o instanceof Candidate) {
4037 Symbol s1 = this.sym;
4038 Symbol s2 = ((Candidate)o).sym;
4039 if ((s1 != s2 &&
4040 (s1.overrides(s2, s1.owner.type.tsym, types, false) ||
4041 (s2.overrides(s1, s2.owner.type.tsym, types, false)))) ||
4042 ((s1.isConstructor() || s2.isConstructor()) && s1.owner != s2.owner))
4043 return true;
4044 }
4045 return false;
4046 }
4048 boolean isApplicable() {
4049 return mtype != null;
4050 }
4051 }
4053 DeferredAttr.AttrMode attrMode() {
4054 return attrMode;
4055 }
4057 boolean internal() {
4058 return internalResolution;
4059 }
4060 }
4062 MethodResolutionContext currentResolutionContext = null;
4063 }
