1 /*
2 * Copyright (c) 1999, 2017, Oracle and/or its affiliates. All rights reserved.
3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
4 *
5 * This code is free software; you can redistribute it and/or modify it
6 * under the terms of the GNU General Public License version 2 only, as
7 * published by the Free Software Foundation. Oracle designates this
8 * particular file as subject to the "Classpath" exception as provided
9 * by Oracle in the LICENSE file that accompanied this code.
10 *
11 * This code is distributed in the hope that it will be useful, but WITHOUT
12 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
13 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
14 * version 2 for more details (a copy is included in the LICENSE file that
15 * accompanied this code).
16 *
17 * You should have received a copy of the GNU General Public License version
18 * 2 along with this work; if not, write to the Free Software Foundation,
19 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
20 *
21 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
22 * or visit www.oracle.com if you need additional information or have any
23 * questions.
24 */
25
26 package com.sun.tools.javac.comp;
27
28 import com.sun.tools.javac.api.Formattable.LocalizedString;
29 import com.sun.tools.javac.code.*;
30 import com.sun.tools.javac.code.Scope.WriteableScope;
31 import com.sun.tools.javac.code.Source.Feature;
32 import com.sun.tools.javac.code.Symbol.*;
33 import com.sun.tools.javac.code.Type.*;
34 import com.sun.tools.javac.comp.Attr.ResultInfo;
35 import com.sun.tools.javac.comp.Check.CheckContext;
36 import com.sun.tools.javac.comp.DeferredAttr.AttrMode;
37 import com.sun.tools.javac.comp.DeferredAttr.DeferredAttrContext;
38 import com.sun.tools.javac.comp.DeferredAttr.DeferredType;
39 import com.sun.tools.javac.comp.Infer.FreeTypeListener;
40 import com.sun.tools.javac.comp.Resolve.MethodResolutionContext.Candidate;
41 import com.sun.tools.javac.comp.Resolve.MethodResolutionDiagHelper.Template;
42 import com.sun.tools.javac.comp.Resolve.ReferenceLookupResult.StaticKind;
43 import com.sun.tools.javac.jvm.*;
44 import com.sun.tools.javac.main.Option;
45 import com.sun.tools.javac.resources.CompilerProperties.Errors;
46 import com.sun.tools.javac.resources.CompilerProperties.Fragments;
47 import com.sun.tools.javac.tree.*;
48 import com.sun.tools.javac.tree.JCTree.*;
49 import com.sun.tools.javac.tree.JCTree.JCMemberReference.ReferenceKind;
50 import com.sun.tools.javac.tree.JCTree.JCPolyExpression.*;
51 import com.sun.tools.javac.util.*;
52 import com.sun.tools.javac.util.DefinedBy.Api;
53 import com.sun.tools.javac.util.JCDiagnostic.DiagnosticFlag;
54 import com.sun.tools.javac.util.JCDiagnostic.DiagnosticPosition;
55 import com.sun.tools.javac.util.JCDiagnostic.DiagnosticType;
56
57 import java.util.Arrays;
58 import java.util.Collection;
59 import java.util.EnumSet;
60 import java.util.HashSet;
61 import java.util.Iterator;
62 import java.util.LinkedHashMap;
63 import java.util.LinkedList;
64 import java.util.Map;
65 import java.util.Set;
66 import java.util.function.BiFunction;
67 import java.util.function.BiPredicate;
68 import java.util.function.Function;
69 import java.util.function.Predicate;
70 import java.util.stream.Stream;
71
72 import javax.lang.model.element.ElementVisitor;
73
74 import static com.sun.tools.javac.code.Flags.*;
75 import static com.sun.tools.javac.code.Flags.BLOCK;
76 import static com.sun.tools.javac.code.Flags.STATIC;
77 import static com.sun.tools.javac.code.Kinds.*;
78 import static com.sun.tools.javac.code.Kinds.Kind.*;
79 import static com.sun.tools.javac.code.TypeTag.*;
80 import static com.sun.tools.javac.comp.Resolve.MethodResolutionPhase.*;
81 import static com.sun.tools.javac.tree.JCTree.Tag.*;
82 import static com.sun.tools.javac.util.Iterators.createCompoundIterator;
83
84 /** Helper class for name resolution, used mostly by the attribution phase.
85 *
86 * <p><b>This is NOT part of any supported API.
87 * If you write code that depends on this, you do so at your own risk.
88 * This code and its internal interfaces are subject to change or
89 * deletion without notice.</b>
90 */
91 public class Resolve {
92 protected static final Context.Key<Resolve> resolveKey = new Context.Key<>();
93
94 Names names;
95 Log log;
96 Symtab syms;
97 Attr attr;
98 DeferredAttr deferredAttr;
99 Check chk;
100 Infer infer;
101 ClassFinder finder;
102 ModuleFinder moduleFinder;
103 Types types;
104 JCDiagnostic.Factory diags;
105 public final boolean allowMethodHandles;
106 public final boolean allowFunctionalInterfaceMostSpecific;
107 public final boolean allowModules;
108 public final boolean checkVarargsAccessAfterResolution;
109 private final boolean compactMethodDiags;
110 private final boolean allowLocalVariableTypeInference;
111 final EnumSet<VerboseResolutionMode> verboseResolutionMode;
112
113 WriteableScope polymorphicSignatureScope;
114
115 protected Resolve(Context context) {
116 context.put(resolveKey, this);
117 syms = Symtab.instance(context);
118
119 varNotFound = new SymbolNotFoundError(ABSENT_VAR);
120 methodNotFound = new SymbolNotFoundError(ABSENT_MTH);
121 typeNotFound = new SymbolNotFoundError(ABSENT_TYP);
122 referenceNotFound = ReferenceLookupResult.error(methodNotFound);
123
124 names = Names.instance(context);
125 log = Log.instance(context);
126 attr = Attr.instance(context);
127 deferredAttr = DeferredAttr.instance(context);
128 chk = Check.instance(context);
129 infer = Infer.instance(context);
130 finder = ClassFinder.instance(context);
131 moduleFinder = ModuleFinder.instance(context);
132 types = Types.instance(context);
133 diags = JCDiagnostic.Factory.instance(context);
134 Source source = Source.instance(context);
135 Options options = Options.instance(context);
136 compactMethodDiags = options.isSet(Option.XDIAGS, "compact") ||
137 options.isUnset(Option.XDIAGS) && options.isUnset("rawDiagnostics");
138 verboseResolutionMode = VerboseResolutionMode.getVerboseResolutionMode(options);
139 Target target = Target.instance(context);
140 allowMethodHandles = target.hasMethodHandles();
141 allowFunctionalInterfaceMostSpecific = Feature.FUNCTIONAL_INTERFACE_MOST_SPECIFIC.allowedInSource(source);
142 allowLocalVariableTypeInference = Feature.LOCAL_VARIABLE_TYPE_INFERENCE.allowedInSource(source);
143 checkVarargsAccessAfterResolution =
144 Feature.POST_APPLICABILITY_VARARGS_ACCESS_CHECK.allowedInSource(source);
145 polymorphicSignatureScope = WriteableScope.create(syms.noSymbol);
146
147 inapplicableMethodException = new InapplicableMethodException(diags);
148
149 allowModules = Feature.MODULES.allowedInSource(source);
150 }
151
152 /** error symbols, which are returned when resolution fails
153 */
154 private final SymbolNotFoundError varNotFound;
155 private final SymbolNotFoundError methodNotFound;
156 private final SymbolNotFoundError typeNotFound;
157
158 /** empty reference lookup result */
159 private final ReferenceLookupResult referenceNotFound;
160
161 public static Resolve instance(Context context) {
162 Resolve instance = context.get(resolveKey);
163 if (instance == null)
164 instance = new Resolve(context);
165 return instance;
166 }
167
168 private static Symbol bestOf(Symbol s1,
169 Symbol s2) {
170 return s1.kind.betterThan(s2.kind) ? s1 : s2;
171 }
172
173 // <editor-fold defaultstate="collapsed" desc="Verbose resolution diagnostics support">
174 enum VerboseResolutionMode {
175 SUCCESS("success"),
176 FAILURE("failure"),
177 APPLICABLE("applicable"),
178 INAPPLICABLE("inapplicable"),
179 DEFERRED_INST("deferred-inference"),
180 PREDEF("predef"),
181 OBJECT_INIT("object-init"),
182 INTERNAL("internal");
183
184 final String opt;
185
186 private VerboseResolutionMode(String opt) {
187 this.opt = opt;
188 }
189
190 static EnumSet<VerboseResolutionMode> getVerboseResolutionMode(Options opts) {
191 String s = opts.get("debug.verboseResolution");
192 EnumSet<VerboseResolutionMode> res = EnumSet.noneOf(VerboseResolutionMode.class);
193 if (s == null) return res;
194 if (s.contains("all")) {
195 res = EnumSet.allOf(VerboseResolutionMode.class);
196 }
197 Collection<String> args = Arrays.asList(s.split(","));
198 for (VerboseResolutionMode mode : values()) {
199 if (args.contains(mode.opt)) {
200 res.add(mode);
201 } else if (args.contains("-" + mode.opt)) {
202 res.remove(mode);
203 }
204 }
205 return res;
206 }
207 }
208
209 void reportVerboseResolutionDiagnostic(DiagnosticPosition dpos, Name name, Type site,
210 List<Type> argtypes, List<Type> typeargtypes, Symbol bestSoFar) {
211 boolean success = !bestSoFar.kind.isResolutionError();
212
213 if (success && !verboseResolutionMode.contains(VerboseResolutionMode.SUCCESS)) {
214 return;
215 } else if (!success && !verboseResolutionMode.contains(VerboseResolutionMode.FAILURE)) {
216 return;
217 }
218
219 if (bestSoFar.name == names.init &&
220 bestSoFar.owner == syms.objectType.tsym &&
221 !verboseResolutionMode.contains(VerboseResolutionMode.OBJECT_INIT)) {
222 return; //skip diags for Object constructor resolution
223 } else if (site == syms.predefClass.type &&
224 !verboseResolutionMode.contains(VerboseResolutionMode.PREDEF)) {
225 return; //skip spurious diags for predef symbols (i.e. operators)
226 } else if (currentResolutionContext.internalResolution &&
227 !verboseResolutionMode.contains(VerboseResolutionMode.INTERNAL)) {
228 return;
229 }
230
231 int pos = 0;
232 int mostSpecificPos = -1;
233 ListBuffer<JCDiagnostic> subDiags = new ListBuffer<>();
234 for (Candidate c : currentResolutionContext.candidates) {
235 if (currentResolutionContext.step != c.step ||
236 (c.isApplicable() && !verboseResolutionMode.contains(VerboseResolutionMode.APPLICABLE)) ||
237 (!c.isApplicable() && !verboseResolutionMode.contains(VerboseResolutionMode.INAPPLICABLE))) {
238 continue;
239 } else {
240 subDiags.append(c.isApplicable() ?
241 getVerboseApplicableCandidateDiag(pos, c.sym, c.mtype) :
242 getVerboseInapplicableCandidateDiag(pos, c.sym, c.details));
243 if (c.sym == bestSoFar)
244 mostSpecificPos = pos;
245 pos++;
246 }
247 }
248 String key = success ? "verbose.resolve.multi" : "verbose.resolve.multi.1";
249 List<Type> argtypes2 = argtypes.map(deferredAttr.new RecoveryDeferredTypeMap(AttrMode.SPECULATIVE, bestSoFar, currentResolutionContext.step));
250 JCDiagnostic main = diags.note(log.currentSource(), dpos, key, name,
251 site.tsym, mostSpecificPos, currentResolutionContext.step,
252 methodArguments(argtypes2),
253 methodArguments(typeargtypes));
254 JCDiagnostic d = new JCDiagnostic.MultilineDiagnostic(main, subDiags.toList());
255 log.report(d);
256 }
257
258 JCDiagnostic getVerboseApplicableCandidateDiag(int pos, Symbol sym, Type inst) {
259 JCDiagnostic subDiag = null;
260 if (sym.type.hasTag(FORALL)) {
261 subDiag = diags.fragment(Fragments.PartialInstSig(inst));
262 }
263
264 String key = subDiag == null ?
265 "applicable.method.found" :
266 "applicable.method.found.1";
267
268 return diags.fragment(key, pos, sym, subDiag);
269 }
270
271 JCDiagnostic getVerboseInapplicableCandidateDiag(int pos, Symbol sym, JCDiagnostic subDiag) {
272 return diags.fragment(Fragments.NotApplicableMethodFound(pos, sym, subDiag));
273 }
274 // </editor-fold>
275
276 /* ************************************************************************
277 * Identifier resolution
278 *************************************************************************/
279
280 /** An environment is "static" if its static level is greater than
281 * the one of its outer environment
282 */
283 protected static boolean isStatic(Env<AttrContext> env) {
284 return env.outer != null && env.info.staticLevel > env.outer.info.staticLevel;
285 }
286
287 /** An environment is an "initializer" if it is a constructor or
288 * an instance initializer.
289 */
290 static boolean isInitializer(Env<AttrContext> env) {
291 Symbol owner = env.info.scope.owner;
292 return owner.isConstructor() ||
293 owner.owner.kind == TYP &&
294 (owner.kind == VAR ||
295 owner.kind == MTH && (owner.flags() & BLOCK) != 0) &&
296 (owner.flags() & STATIC) == 0;
297 }
298
299 /** Is class accessible in given evironment?
300 * @param env The current environment.
301 * @param c The class whose accessibility is checked.
302 */
303 public boolean isAccessible(Env<AttrContext> env, TypeSymbol c) {
304 return isAccessible(env, c, false);
305 }
306
307 public boolean isAccessible(Env<AttrContext> env, TypeSymbol c, boolean checkInner) {
308
309 /* 15.9.5.1: Note that it is possible for the signature of the anonymous constructor
310 to refer to an inaccessible type
311 */
312 if (env.enclMethod != null && (env.enclMethod.mods.flags & ANONCONSTR) != 0)
313 return true;
314
315 if (env.info.visitingServiceImplementation &&
316 env.toplevel.modle == c.packge().modle) {
317 return true;
318 }
319
320 boolean isAccessible = false;
321 switch ((short)(c.flags() & AccessFlags)) {
322 case PRIVATE:
323 isAccessible =
324 env.enclClass.sym.outermostClass() ==
325 c.owner.outermostClass();
326 break;
327 case 0:
328 isAccessible =
329 env.toplevel.packge == c.owner // fast special case
330 ||
331 env.toplevel.packge == c.packge();
332 break;
333 default: // error recovery
334 isAccessible = true;
335 break;
336 case PUBLIC:
337 if (allowModules) {
338 ModuleSymbol currModule = env.toplevel.modle;
339 currModule.complete();
340 PackageSymbol p = c.packge();
341 isAccessible =
342 currModule == p.modle ||
343 currModule.visiblePackages.get(p.fullname) == p ||
344 p == syms.rootPackage ||
345 (p.modle == syms.unnamedModule && currModule.readModules.contains(p.modle));
346 } else {
347 isAccessible = true;
348 }
349 break;
350 case PROTECTED:
351 isAccessible =
352 env.toplevel.packge == c.owner // fast special case
353 ||
354 env.toplevel.packge == c.packge()
355 ||
356 isInnerSubClass(env.enclClass.sym, c.owner);
357 break;
358 }
359 return (checkInner == false || c.type.getEnclosingType() == Type.noType) ?
360 isAccessible :
361 isAccessible && isAccessible(env, c.type.getEnclosingType(), checkInner);
362 }
363 //where
364 /** Is given class a subclass of given base class, or an inner class
365 * of a subclass?
366 * Return null if no such class exists.
367 * @param c The class which is the subclass or is contained in it.
368 * @param base The base class
369 */
370 private boolean isInnerSubClass(ClassSymbol c, Symbol base) {
371 while (c != null && !c.isSubClass(base, types)) {
372 c = c.owner.enclClass();
373 }
374 return c != null;
375 }
376
377 boolean isAccessible(Env<AttrContext> env, Type t) {
378 return isAccessible(env, t, false);
379 }
380
381 boolean isAccessible(Env<AttrContext> env, Type t, boolean checkInner) {
382 return (t.hasTag(ARRAY))
383 ? isAccessible(env, types.cvarUpperBound(types.elemtype(t)))
384 : isAccessible(env, t.tsym, checkInner);
385 }
386
387 /** Is symbol accessible as a member of given type in given environment?
388 * @param env The current environment.
389 * @param site The type of which the tested symbol is regarded
390 * as a member.
391 * @param sym The symbol.
392 */
393 public boolean isAccessible(Env<AttrContext> env, Type site, Symbol sym) {
394 return isAccessible(env, site, sym, false);
395 }
396 public boolean isAccessible(Env<AttrContext> env, Type site, Symbol sym, boolean checkInner) {
397 if (sym.name == names.init && sym.owner != site.tsym) return false;
398
399 /* 15.9.5.1: Note that it is possible for the signature of the anonymous constructor
400 to refer to an inaccessible type
401 */
402 if (env.enclMethod != null && (env.enclMethod.mods.flags & ANONCONSTR) != 0)
403 return true;
404
405 if (env.info.visitingServiceImplementation &&
406 env.toplevel.modle == sym.packge().modle) {
407 return true;
408 }
409
410 switch ((short)(sym.flags() & AccessFlags)) {
411 case PRIVATE:
412 return
413 (env.enclClass.sym == sym.owner // fast special case
414 ||
415 env.enclClass.sym.outermostClass() ==
416 sym.owner.outermostClass())
417 &&
418 sym.isInheritedIn(site.tsym, types);
419 case 0:
420 return
421 (env.toplevel.packge == sym.owner.owner // fast special case
422 ||
423 env.toplevel.packge == sym.packge())
424 &&
425 isAccessible(env, site, checkInner)
426 &&
427 sym.isInheritedIn(site.tsym, types)
428 &&
429 notOverriddenIn(site, sym);
430 case PROTECTED:
431 return
432 (env.toplevel.packge == sym.owner.owner // fast special case
433 ||
434 env.toplevel.packge == sym.packge()
435 ||
436 isProtectedAccessible(sym, env.enclClass.sym, site)
437 ||
438 // OK to select instance method or field from 'super' or type name
439 // (but type names should be disallowed elsewhere!)
440 env.info.selectSuper && (sym.flags() & STATIC) == 0 && sym.kind != TYP)
441 &&
442 isAccessible(env, site, checkInner)
443 &&
444 notOverriddenIn(site, sym);
445 default: // this case includes erroneous combinations as well
446 return isAccessible(env, site, checkInner) && notOverriddenIn(site, sym);
447 }
448 }
449 //where
450 /* `sym' is accessible only if not overridden by
451 * another symbol which is a member of `site'
452 * (because, if it is overridden, `sym' is not strictly
453 * speaking a member of `site'). A polymorphic signature method
454 * cannot be overridden (e.g. MH.invokeExact(Object[])).
455 */
456 private boolean notOverriddenIn(Type site, Symbol sym) {
457 if (sym.kind != MTH || sym.isConstructor() || sym.isStatic())
458 return true;
459 else {
460 Symbol s2 = ((MethodSymbol)sym).implementation(site.tsym, types, true);
461 return (s2 == null || s2 == sym || sym.owner == s2.owner ||
462 !types.isSubSignature(types.memberType(site, s2), types.memberType(site, sym)));
463 }
464 }
465 //where
466 /** Is given protected symbol accessible if it is selected from given site
467 * and the selection takes place in given class?
468 * @param sym The symbol with protected access
469 * @param c The class where the access takes place
470 * @site The type of the qualifier
471 */
472 private
473 boolean isProtectedAccessible(Symbol sym, ClassSymbol c, Type site) {
474 Type newSite = site.hasTag(TYPEVAR) ? site.getUpperBound() : site;
475 while (c != null &&
476 !(c.isSubClass(sym.owner, types) &&
477 (c.flags() & INTERFACE) == 0 &&
478 // In JLS 2e 6.6.2.1, the subclass restriction applies
479 // only to instance fields and methods -- types are excluded
480 // regardless of whether they are declared 'static' or not.
481 ((sym.flags() & STATIC) != 0 || sym.kind == TYP || newSite.tsym.isSubClass(c, types))))
482 c = c.owner.enclClass();
483 return c != null;
484 }
485
486 /**
487 * Performs a recursive scan of a type looking for accessibility problems
488 * from current attribution environment
489 */
490 void checkAccessibleType(Env<AttrContext> env, Type t) {
491 accessibilityChecker.visit(t, env);
492 }
493
494 /**
495 * Accessibility type-visitor
496 */
497 Types.SimpleVisitor<Void, Env<AttrContext>> accessibilityChecker =
498 new Types.SimpleVisitor<Void, Env<AttrContext>>() {
499
500 void visit(List<Type> ts, Env<AttrContext> env) {
501 for (Type t : ts) {
502 visit(t, env);
503 }
504 }
505
506 public Void visitType(Type t, Env<AttrContext> env) {
507 return null;
508 }
509
510 @Override
511 public Void visitArrayType(ArrayType t, Env<AttrContext> env) {
512 visit(t.elemtype, env);
513 return null;
514 }
515
516 @Override
517 public Void visitClassType(ClassType t, Env<AttrContext> env) {
518 visit(t.getTypeArguments(), env);
519 if (!isAccessible(env, t, true)) {
520 accessBase(new AccessError(env, null, t.tsym), env.tree.pos(), env.enclClass.sym, t, t.tsym.name, true);
521 }
522 return null;
523 }
524
525 @Override
526 public Void visitWildcardType(WildcardType t, Env<AttrContext> env) {
527 visit(t.type, env);
528 return null;
529 }
530
531 @Override
532 public Void visitMethodType(MethodType t, Env<AttrContext> env) {
533 visit(t.getParameterTypes(), env);
534 visit(t.getReturnType(), env);
535 visit(t.getThrownTypes(), env);
536 return null;
537 }
538 };
539
540 /** Try to instantiate the type of a method so that it fits
541 * given type arguments and argument types. If successful, return
542 * the method's instantiated type, else return null.
543 * The instantiation will take into account an additional leading
544 * formal parameter if the method is an instance method seen as a member
545 * of an under determined site. In this case, we treat site as an additional
546 * parameter and the parameters of the class containing the method as
547 * additional type variables that get instantiated.
548 *
549 * @param env The current environment
550 * @param site The type of which the method is a member.
551 * @param m The method symbol.
552 * @param argtypes The invocation's given value arguments.
553 * @param typeargtypes The invocation's given type arguments.
554 * @param allowBoxing Allow boxing conversions of arguments.
555 * @param useVarargs Box trailing arguments into an array for varargs.
556 */
557 Type rawInstantiate(Env<AttrContext> env,
558 Type site,
559 Symbol m,
560 ResultInfo resultInfo,
561 List<Type> argtypes,
562 List<Type> typeargtypes,
563 boolean allowBoxing,
564 boolean useVarargs,
565 Warner warn) throws Infer.InferenceException {
566 Type mt = types.memberType(site, m);
567 // tvars is the list of formal type variables for which type arguments
568 // need to inferred.
569 List<Type> tvars = List.nil();
570 if (typeargtypes == null) typeargtypes = List.nil();
571 if (!mt.hasTag(FORALL) && typeargtypes.nonEmpty()) {
572 // This is not a polymorphic method, but typeargs are supplied
573 // which is fine, see JLS 15.12.2.1
574 } else if (mt.hasTag(FORALL) && typeargtypes.nonEmpty()) {
575 ForAll pmt = (ForAll) mt;
576 if (typeargtypes.length() != pmt.tvars.length())
577 // not enough args
578 throw inapplicableMethodException.setMessage("wrong.number.type.args", Integer.toString(pmt.tvars.length()));
579 // Check type arguments are within bounds
580 List<Type> formals = pmt.tvars;
581 List<Type> actuals = typeargtypes;
582 while (formals.nonEmpty() && actuals.nonEmpty()) {
583 List<Type> bounds = types.subst(types.getBounds((TypeVar)formals.head),
584 pmt.tvars, typeargtypes);
585 for (; bounds.nonEmpty(); bounds = bounds.tail) {
586 if (!types.isSubtypeUnchecked(actuals.head, bounds.head, warn))
587 throw inapplicableMethodException.setMessage("explicit.param.do.not.conform.to.bounds",actuals.head, bounds);
588 }
589 formals = formals.tail;
590 actuals = actuals.tail;
591 }
592 mt = types.subst(pmt.qtype, pmt.tvars, typeargtypes);
593 } else if (mt.hasTag(FORALL)) {
594 ForAll pmt = (ForAll) mt;
595 List<Type> tvars1 = types.newInstances(pmt.tvars);
596 tvars = tvars.appendList(tvars1);
597 mt = types.subst(pmt.qtype, pmt.tvars, tvars1);
598 }
599
600 // find out whether we need to go the slow route via infer
601 boolean instNeeded = tvars.tail != null; /*inlined: tvars.nonEmpty()*/
602 for (List<Type> l = argtypes;
603 l.tail != null/*inlined: l.nonEmpty()*/ && !instNeeded;
604 l = l.tail) {
605 if (l.head.hasTag(FORALL)) instNeeded = true;
606 }
607
608 if (instNeeded) {
609 return infer.instantiateMethod(env,
610 tvars,
611 (MethodType)mt,
612 resultInfo,
613 (MethodSymbol)m,
614 argtypes,
615 allowBoxing,
616 useVarargs,
617 currentResolutionContext,
618 warn);
619 }
620
621 DeferredAttr.DeferredAttrContext dc = currentResolutionContext.deferredAttrContext(m, infer.emptyContext, resultInfo, warn);
622 currentResolutionContext.methodCheck.argumentsAcceptable(env, dc,
623 argtypes, mt.getParameterTypes(), warn);
624 dc.complete();
625 return mt;
626 }
627
628 Type checkMethod(Env<AttrContext> env,
629 Type site,
630 Symbol m,
631 ResultInfo resultInfo,
632 List<Type> argtypes,
633 List<Type> typeargtypes,
634 Warner warn) {
635 MethodResolutionContext prevContext = currentResolutionContext;
636 try {
637 currentResolutionContext = new MethodResolutionContext();
638 currentResolutionContext.attrMode = (resultInfo.pt == Infer.anyPoly) ?
639 AttrMode.SPECULATIVE : DeferredAttr.AttrMode.CHECK;
640 if (env.tree.hasTag(JCTree.Tag.REFERENCE)) {
641 //method/constructor references need special check class
642 //to handle inference variables in 'argtypes' (might happen
643 //during an unsticking round)
644 currentResolutionContext.methodCheck =
645 new MethodReferenceCheck(resultInfo.checkContext.inferenceContext());
646 }
647 MethodResolutionPhase step = currentResolutionContext.step = env.info.pendingResolutionPhase;
648 return rawInstantiate(env, site, m, resultInfo, argtypes, typeargtypes,
649 step.isBoxingRequired(), step.isVarargsRequired(), warn);
650 }
651 finally {
652 currentResolutionContext = prevContext;
653 }
654 }
655
656 /** Same but returns null instead throwing a NoInstanceException
657 */
658 Type instantiate(Env<AttrContext> env,
659 Type site,
660 Symbol m,
661 ResultInfo resultInfo,
662 List<Type> argtypes,
663 List<Type> typeargtypes,
664 boolean allowBoxing,
665 boolean useVarargs,
666 Warner warn) {
667 try {
668 return rawInstantiate(env, site, m, resultInfo, argtypes, typeargtypes,
669 allowBoxing, useVarargs, warn);
670 } catch (InapplicableMethodException ex) {
671 return null;
672 }
673 }
674
675 /**
676 * This interface defines an entry point that should be used to perform a
677 * method check. A method check usually consist in determining as to whether
678 * a set of types (actuals) is compatible with another set of types (formals).
679 * Since the notion of compatibility can vary depending on the circumstances,
680 * this interfaces allows to easily add new pluggable method check routines.
681 */
682 interface MethodCheck {
683 /**
684 * Main method check routine. A method check usually consist in determining
685 * as to whether a set of types (actuals) is compatible with another set of
686 * types (formals). If an incompatibility is found, an unchecked exception
687 * is assumed to be thrown.
688 */
689 void argumentsAcceptable(Env<AttrContext> env,
690 DeferredAttrContext deferredAttrContext,
691 List<Type> argtypes,
692 List<Type> formals,
693 Warner warn);
694
695 /**
696 * Retrieve the method check object that will be used during a
697 * most specific check.
698 */
699 MethodCheck mostSpecificCheck(List<Type> actuals);
700 }
701
702 /**
703 * Helper enum defining all method check diagnostics (used by resolveMethodCheck).
704 */
705 enum MethodCheckDiag {
706 /**
707 * Actuals and formals differs in length.
708 */
709 ARITY_MISMATCH("arg.length.mismatch", "infer.arg.length.mismatch"),
710 /**
711 * An actual is incompatible with a formal.
712 */
713 ARG_MISMATCH("no.conforming.assignment.exists", "infer.no.conforming.assignment.exists"),
714 /**
715 * An actual is incompatible with the varargs element type.
716 */
717 VARARG_MISMATCH("varargs.argument.mismatch", "infer.varargs.argument.mismatch"),
718 /**
719 * The varargs element type is inaccessible.
720 */
721 INACCESSIBLE_VARARGS("inaccessible.varargs.type", "inaccessible.varargs.type");
722
723 final String basicKey;
724 final String inferKey;
725
726 MethodCheckDiag(String basicKey, String inferKey) {
727 this.basicKey = basicKey;
728 this.inferKey = inferKey;
729 }
730
731 String regex() {
732 return String.format("([a-z]*\\.)*(%s|%s)", basicKey, inferKey);
733 }
734 }
735
736 /**
737 * Dummy method check object. All methods are deemed applicable, regardless
738 * of their formal parameter types.
739 */
740 MethodCheck nilMethodCheck = new MethodCheck() {
741 public void argumentsAcceptable(Env<AttrContext> env, DeferredAttrContext deferredAttrContext, List<Type> argtypes, List<Type> formals, Warner warn) {
742 //do nothing - method always applicable regardless of actuals
743 }
744
745 public MethodCheck mostSpecificCheck(List<Type> actuals) {
746 return this;
747 }
748 };
749
750 /**
751 * Base class for 'real' method checks. The class defines the logic for
752 * iterating through formals and actuals and provides and entry point
753 * that can be used by subclasses in order to define the actual check logic.
754 */
755 abstract class AbstractMethodCheck implements MethodCheck {
756 @Override
757 public void argumentsAcceptable(final Env<AttrContext> env,
758 DeferredAttrContext deferredAttrContext,
759 List<Type> argtypes,
760 List<Type> formals,
761 Warner warn) {
762 //should we expand formals?
763 boolean useVarargs = deferredAttrContext.phase.isVarargsRequired();
764 JCTree callTree = treeForDiagnostics(env);
765 List<JCExpression> trees = TreeInfo.args(callTree);
766
767 //inference context used during this method check
768 InferenceContext inferenceContext = deferredAttrContext.inferenceContext;
769
770 Type varargsFormal = useVarargs ? formals.last() : null;
771
772 if (varargsFormal == null &&
773 argtypes.size() != formals.size()) {
774 reportMC(callTree, MethodCheckDiag.ARITY_MISMATCH, inferenceContext); // not enough args
775 }
776
777 while (argtypes.nonEmpty() && formals.head != varargsFormal) {
778 DiagnosticPosition pos = trees != null ? trees.head : null;
779 checkArg(pos, false, argtypes.head, formals.head, deferredAttrContext, warn);
780 argtypes = argtypes.tail;
781 formals = formals.tail;
782 trees = trees != null ? trees.tail : trees;
783 }
784
785 if (formals.head != varargsFormal) {
786 reportMC(callTree, MethodCheckDiag.ARITY_MISMATCH, inferenceContext); // not enough args
787 }
788
789 if (useVarargs) {
790 //note: if applicability check is triggered by most specific test,
791 //the last argument of a varargs is _not_ an array type (see JLS 15.12.2.5)
792 final Type elt = types.elemtype(varargsFormal);
793 while (argtypes.nonEmpty()) {
794 DiagnosticPosition pos = trees != null ? trees.head : null;
795 checkArg(pos, true, argtypes.head, elt, deferredAttrContext, warn);
796 argtypes = argtypes.tail;
797 trees = trees != null ? trees.tail : trees;
798 }
799 }
800 }
801
802 // where
803 private JCTree treeForDiagnostics(Env<AttrContext> env) {
804 return env.info.preferredTreeForDiagnostics != null ? env.info.preferredTreeForDiagnostics : env.tree;
805 }
806
807 /**
808 * Does the actual argument conforms to the corresponding formal?
809 */
810 abstract void checkArg(DiagnosticPosition pos, boolean varargs, Type actual, Type formal, DeferredAttrContext deferredAttrContext, Warner warn);
811
812 protected void reportMC(DiagnosticPosition pos, MethodCheckDiag diag, InferenceContext inferenceContext, Object... args) {
813 boolean inferDiag = inferenceContext != infer.emptyContext;
814 InapplicableMethodException ex = inferDiag ?
815 infer.inferenceException : inapplicableMethodException;
816 if (inferDiag && (!diag.inferKey.equals(diag.basicKey))) {
817 Object[] args2 = new Object[args.length + 1];
818 System.arraycopy(args, 0, args2, 1, args.length);
819 args2[0] = inferenceContext.inferenceVars();
820 args = args2;
821 }
822 String key = inferDiag ? diag.inferKey : diag.basicKey;
823 throw ex.setMessage(diags.create(DiagnosticType.FRAGMENT, log.currentSource(), pos, key, args));
824 }
825
826 public MethodCheck mostSpecificCheck(List<Type> actuals) {
827 return nilMethodCheck;
828 }
829
830 }
831
832 /**
833 * Arity-based method check. A method is applicable if the number of actuals
834 * supplied conforms to the method signature.
835 */
836 MethodCheck arityMethodCheck = new AbstractMethodCheck() {
837 @Override
838 void checkArg(DiagnosticPosition pos, boolean varargs, Type actual, Type formal, DeferredAttrContext deferredAttrContext, Warner warn) {
839 //do nothing - actual always compatible to formals
840 }
841
842 @Override
843 public String toString() {
844 return "arityMethodCheck";
845 }
846 };
847
848 /**
849 * Main method applicability routine. Given a list of actual types A,
850 * a list of formal types F, determines whether the types in A are
851 * compatible (by method invocation conversion) with the types in F.
852 *
853 * Since this routine is shared between overload resolution and method
854 * type-inference, a (possibly empty) inference context is used to convert
855 * formal types to the corresponding 'undet' form ahead of a compatibility
856 * check so that constraints can be propagated and collected.
857 *
858 * Moreover, if one or more types in A is a deferred type, this routine uses
859 * DeferredAttr in order to perform deferred attribution. If one or more actual
860 * deferred types are stuck, they are placed in a queue and revisited later
861 * after the remainder of the arguments have been seen. If this is not sufficient
862 * to 'unstuck' the argument, a cyclic inference error is called out.
863 *
864 * A method check handler (see above) is used in order to report errors.
865 */
866 MethodCheck resolveMethodCheck = new AbstractMethodCheck() {
867
868 @Override
869 void checkArg(DiagnosticPosition pos, boolean varargs, Type actual, Type formal, DeferredAttrContext deferredAttrContext, Warner warn) {
870 ResultInfo mresult = methodCheckResult(varargs, formal, deferredAttrContext, warn);
871 mresult.check(pos, actual);
872 }
873
874 @Override
875 public void argumentsAcceptable(final Env<AttrContext> env,
876 DeferredAttrContext deferredAttrContext,
877 List<Type> argtypes,
878 List<Type> formals,
879 Warner warn) {
880 super.argumentsAcceptable(env, deferredAttrContext, argtypes, formals, warn);
881 // should we check varargs element type accessibility?
882 if (deferredAttrContext.phase.isVarargsRequired()) {
883 if (deferredAttrContext.mode == AttrMode.CHECK || !checkVarargsAccessAfterResolution) {
884 varargsAccessible(env, types.elemtype(formals.last()), deferredAttrContext.inferenceContext);
885 }
886 }
887 }
888
889 /**
890 * Test that the runtime array element type corresponding to 't' is accessible. 't' should be the
891 * varargs element type of either the method invocation type signature (after inference completes)
892 * or the method declaration signature (before inference completes).
893 */
894 private void varargsAccessible(final Env<AttrContext> env, final Type t, final InferenceContext inferenceContext) {
895 if (inferenceContext.free(t)) {
896 inferenceContext.addFreeTypeListener(List.of(t),
897 solvedContext -> varargsAccessible(env, solvedContext.asInstType(t), solvedContext));
898 } else {
899 if (!isAccessible(env, types.erasure(t))) {
900 Symbol location = env.enclClass.sym;
901 reportMC(env.tree, MethodCheckDiag.INACCESSIBLE_VARARGS, inferenceContext, t, Kinds.kindName(location), location);
902 }
903 }
904 }
905
906 private ResultInfo methodCheckResult(final boolean varargsCheck, Type to,
907 final DeferredAttr.DeferredAttrContext deferredAttrContext, Warner rsWarner) {
908 CheckContext checkContext = new MethodCheckContext(!deferredAttrContext.phase.isBoxingRequired(), deferredAttrContext, rsWarner) {
909 MethodCheckDiag methodDiag = varargsCheck ?
910 MethodCheckDiag.VARARG_MISMATCH : MethodCheckDiag.ARG_MISMATCH;
911
912 @Override
913 public void report(DiagnosticPosition pos, JCDiagnostic details) {
914 reportMC(pos, methodDiag, deferredAttrContext.inferenceContext, details);
915 }
916 };
917 return new MethodResultInfo(to, checkContext);
918 }
919
920 @Override
921 public MethodCheck mostSpecificCheck(List<Type> actuals) {
922 return new MostSpecificCheck(actuals);
923 }
924
925 @Override
926 public String toString() {
927 return "resolveMethodCheck";
928 }
929 };
930
931 /**
932 * This class handles method reference applicability checks; since during
933 * these checks it's sometime possible to have inference variables on
934 * the actual argument types list, the method applicability check must be
935 * extended so that inference variables are 'opened' as needed.
936 */
937 class MethodReferenceCheck extends AbstractMethodCheck {
938
939 InferenceContext pendingInferenceContext;
940
941 MethodReferenceCheck(InferenceContext pendingInferenceContext) {
942 this.pendingInferenceContext = pendingInferenceContext;
943 }
944
945 @Override
946 void checkArg(DiagnosticPosition pos, boolean varargs, Type actual, Type formal, DeferredAttrContext deferredAttrContext, Warner warn) {
947 ResultInfo mresult = methodCheckResult(varargs, formal, deferredAttrContext, warn);
948 mresult.check(pos, actual);
949 }
950
951 private ResultInfo methodCheckResult(final boolean varargsCheck, Type to,
952 final DeferredAttr.DeferredAttrContext deferredAttrContext, Warner rsWarner) {
953 CheckContext checkContext = new MethodCheckContext(!deferredAttrContext.phase.isBoxingRequired(), deferredAttrContext, rsWarner) {
954 MethodCheckDiag methodDiag = varargsCheck ?
955 MethodCheckDiag.VARARG_MISMATCH : MethodCheckDiag.ARG_MISMATCH;
956
957 @Override
958 public boolean compatible(Type found, Type req, Warner warn) {
959 found = pendingInferenceContext.asUndetVar(found);
960 if (found.hasTag(UNDETVAR) && req.isPrimitive()) {
961 req = types.boxedClass(req).type;
962 }
963 return super.compatible(found, req, warn);
964 }
965
966 @Override
967 public void report(DiagnosticPosition pos, JCDiagnostic details) {
968 reportMC(pos, methodDiag, deferredAttrContext.inferenceContext, details);
969 }
970 };
971 return new MethodResultInfo(to, checkContext);
972 }
973
974 @Override
975 public MethodCheck mostSpecificCheck(List<Type> actuals) {
976 return new MostSpecificCheck(actuals);
977 }
978
979 @Override
980 public String toString() {
981 return "MethodReferenceCheck";
982 }
983 }
984
985 /**
986 * Check context to be used during method applicability checks. A method check
987 * context might contain inference variables.
988 */
989 abstract class MethodCheckContext implements CheckContext {
990
991 boolean strict;
992 DeferredAttrContext deferredAttrContext;
993 Warner rsWarner;
994
995 public MethodCheckContext(boolean strict, DeferredAttrContext deferredAttrContext, Warner rsWarner) {
996 this.strict = strict;
997 this.deferredAttrContext = deferredAttrContext;
998 this.rsWarner = rsWarner;
999 }
1000
1001 public boolean compatible(Type found, Type req, Warner warn) {
1002 InferenceContext inferenceContext = deferredAttrContext.inferenceContext;
1003 return strict ?
1004 types.isSubtypeUnchecked(inferenceContext.asUndetVar(found), inferenceContext.asUndetVar(req), warn) :
1005 types.isConvertible(inferenceContext.asUndetVar(found), inferenceContext.asUndetVar(req), warn);
1006 }
1007
1008 public void report(DiagnosticPosition pos, JCDiagnostic details) {
1009 throw inapplicableMethodException.setMessage(details);
1010 }
1011
1012 public Warner checkWarner(DiagnosticPosition pos, Type found, Type req) {
1013 return rsWarner;
1014 }
1015
1016 public InferenceContext inferenceContext() {
1017 return deferredAttrContext.inferenceContext;
1018 }
1019
1020 public DeferredAttrContext deferredAttrContext() {
1021 return deferredAttrContext;
1022 }
1023
1024 @Override
1025 public String toString() {
1026 return "MethodCheckContext";
1027 }
1028 }
1029
1030 /**
1031 * ResultInfo class to be used during method applicability checks. Check
1032 * for deferred types goes through special path.
1033 */
1034 class MethodResultInfo extends ResultInfo {
1035
1036 public MethodResultInfo(Type pt, CheckContext checkContext) {
1037 attr.super(KindSelector.VAL, pt, checkContext);
1038 }
1039
1040 @Override
1041 protected Type check(DiagnosticPosition pos, Type found) {
1042 if (found.hasTag(DEFERRED)) {
1043 DeferredType dt = (DeferredType)found;
1044 return dt.check(this);
1045 } else {
1046 Type uResult = U(found);
1047 Type capturedType = pos == null || pos.getTree() == null ?
1048 types.capture(uResult) :
1049 checkContext.inferenceContext()
1050 .cachedCapture(pos.getTree(), uResult, true);
1051 return super.check(pos, chk.checkNonVoid(pos, capturedType));
1052 }
1053 }
1054
1055 /**
1056 * javac has a long-standing 'simplification' (see 6391995):
1057 * given an actual argument type, the method check is performed
1058 * on its upper bound. This leads to inconsistencies when an
1059 * argument type is checked against itself. For example, given
1060 * a type-variable T, it is not true that {@code U(T) <: T},
1061 * so we need to guard against that.
1062 */
1063 private Type U(Type found) {
1064 return found == pt ?
1065 found : types.cvarUpperBound(found);
1066 }
1067
1068 @Override
1069 protected MethodResultInfo dup(Type newPt) {
1070 return new MethodResultInfo(newPt, checkContext);
1071 }
1072
1073 @Override
1074 protected ResultInfo dup(CheckContext newContext) {
1075 return new MethodResultInfo(pt, newContext);
1076 }
1077
1078 @Override
1079 protected ResultInfo dup(Type newPt, CheckContext newContext) {
1080 return new MethodResultInfo(newPt, newContext);
1081 }
1082 }
1083
1084 /**
1085 * Most specific method applicability routine. Given a list of actual types A,
1086 * a list of formal types F1, and a list of formal types F2, the routine determines
1087 * as to whether the types in F1 can be considered more specific than those in F2 w.r.t.
1088 * argument types A.
1089 */
1090 class MostSpecificCheck implements MethodCheck {
1091
1092 List<Type> actuals;
1093
1094 MostSpecificCheck(List<Type> actuals) {
1095 this.actuals = actuals;
1096 }
1097
1098 @Override
1099 public void argumentsAcceptable(final Env<AttrContext> env,
1100 DeferredAttrContext deferredAttrContext,
1101 List<Type> formals1,
1102 List<Type> formals2,
1103 Warner warn) {
1104 formals2 = adjustArgs(formals2, deferredAttrContext.msym, formals1.length(), deferredAttrContext.phase.isVarargsRequired());
1105 while (formals2.nonEmpty()) {
1106 ResultInfo mresult = methodCheckResult(formals2.head, deferredAttrContext, warn, actuals.head);
1107 mresult.check(null, formals1.head);
1108 formals1 = formals1.tail;
1109 formals2 = formals2.tail;
1110 actuals = actuals.isEmpty() ? actuals : actuals.tail;
1111 }
1112 }
1113
1114 /**
1115 * Create a method check context to be used during the most specific applicability check
1116 */
1117 ResultInfo methodCheckResult(Type to, DeferredAttr.DeferredAttrContext deferredAttrContext,
1118 Warner rsWarner, Type actual) {
1119 return attr.new ResultInfo(KindSelector.VAL, to,
1120 new MostSpecificCheckContext(deferredAttrContext, rsWarner, actual));
1121 }
1122
1123 /**
1124 * Subclass of method check context class that implements most specific
1125 * method conversion. If the actual type under analysis is a deferred type
1126 * a full blown structural analysis is carried out.
1127 */
1128 class MostSpecificCheckContext extends MethodCheckContext {
1129
1130 Type actual;
1131
1132 public MostSpecificCheckContext(DeferredAttrContext deferredAttrContext, Warner rsWarner, Type actual) {
1133 super(true, deferredAttrContext, rsWarner);
1134 this.actual = actual;
1135 }
1136
1137 public boolean compatible(Type found, Type req, Warner warn) {
1138 if (allowFunctionalInterfaceMostSpecific &&
1139 unrelatedFunctionalInterfaces(found, req) &&
1140 (actual != null && actual.getTag() == DEFERRED)) {
1141 DeferredType dt = (DeferredType) actual;
1142 JCTree speculativeTree = dt.speculativeTree(deferredAttrContext);
1143 if (speculativeTree != deferredAttr.stuckTree) {
1144 return functionalInterfaceMostSpecific(found, req, speculativeTree);
1145 }
1146 }
1147 return compatibleBySubtyping(found, req);
1148 }
1149
1150 private boolean compatibleBySubtyping(Type found, Type req) {
1151 if (!strict && found.isPrimitive() != req.isPrimitive()) {
1152 found = found.isPrimitive() ? types.boxedClass(found).type : types.unboxedType(found);
1153 }
1154 return types.isSubtypeNoCapture(found, deferredAttrContext.inferenceContext.asUndetVar(req));
1155 }
1156
1157 /** Whether {@code t} and {@code s} are unrelated functional interface types. */
1158 private boolean unrelatedFunctionalInterfaces(Type t, Type s) {
1159 return types.isFunctionalInterface(t.tsym) &&
1160 types.isFunctionalInterface(s.tsym) &&
1161 unrelatedInterfaces(t, s);
1162 }
1163
1164 /** Whether {@code t} and {@code s} are unrelated interface types; recurs on intersections. **/
1165 private boolean unrelatedInterfaces(Type t, Type s) {
1166 if (t.isCompound()) {
1167 for (Type ti : types.interfaces(t)) {
1168 if (!unrelatedInterfaces(ti, s)) {
1169 return false;
1170 }
1171 }
1172 return true;
1173 } else if (s.isCompound()) {
1174 for (Type si : types.interfaces(s)) {
1175 if (!unrelatedInterfaces(t, si)) {
1176 return false;
1177 }
1178 }
1179 return true;
1180 } else {
1181 return types.asSuper(t, s.tsym) == null && types.asSuper(s, t.tsym) == null;
1182 }
1183 }
1184
1185 /** Parameters {@code t} and {@code s} are unrelated functional interface types. */
1186 private boolean functionalInterfaceMostSpecific(Type t, Type s, JCTree tree) {
1187 Type tDesc = types.findDescriptorType(types.capture(t));
1188 Type tDescNoCapture = types.findDescriptorType(t);
1189 Type sDesc = types.findDescriptorType(s);
1190 final List<Type> tTypeParams = tDesc.getTypeArguments();
1191 final List<Type> tTypeParamsNoCapture = tDescNoCapture.getTypeArguments();
1192 final List<Type> sTypeParams = sDesc.getTypeArguments();
1193
1194 // compare type parameters
1195 if (tDesc.hasTag(FORALL) && !types.hasSameBounds((ForAll) tDesc, (ForAll) tDescNoCapture)) {
1196 return false;
1197 }
1198 // can't use Types.hasSameBounds on sDesc because bounds may have ivars
1199 List<Type> tIter = tTypeParams;
1200 List<Type> sIter = sTypeParams;
1201 while (tIter.nonEmpty() && sIter.nonEmpty()) {
1202 Type tBound = tIter.head.getUpperBound();
1203 Type sBound = types.subst(sIter.head.getUpperBound(), sTypeParams, tTypeParams);
1204 if (tBound.containsAny(tTypeParams) && inferenceContext().free(sBound)) {
1205 return false;
1206 }
1207 if (!types.isSameType(tBound, inferenceContext().asUndetVar(sBound))) {
1208 return false;
1209 }
1210 tIter = tIter.tail;
1211 sIter = sIter.tail;
1212 }
1213 if (!tIter.isEmpty() || !sIter.isEmpty()) {
1214 return false;
1215 }
1216
1217 // compare parameters
1218 List<Type> tParams = tDesc.getParameterTypes();
1219 List<Type> tParamsNoCapture = tDescNoCapture.getParameterTypes();
1220 List<Type> sParams = sDesc.getParameterTypes();
1221 while (tParams.nonEmpty() && tParamsNoCapture.nonEmpty() && sParams.nonEmpty()) {
1222 Type tParam = tParams.head;
1223 Type tParamNoCapture = types.subst(tParamsNoCapture.head, tTypeParamsNoCapture, tTypeParams);
1224 Type sParam = types.subst(sParams.head, sTypeParams, tTypeParams);
1225 if (tParam.containsAny(tTypeParams) && inferenceContext().free(sParam)) {
1226 return false;
1227 }
1228 if (!types.isSubtype(inferenceContext().asUndetVar(sParam), tParam)) {
1229 return false;
1230 }
1231 if (!types.isSameType(tParamNoCapture, inferenceContext().asUndetVar(sParam))) {
1232 return false;
1233 }
1234 tParams = tParams.tail;
1235 tParamsNoCapture = tParamsNoCapture.tail;
1236 sParams = sParams.tail;
1237 }
1238 if (!tParams.isEmpty() || !tParamsNoCapture.isEmpty() || !sParams.isEmpty()) {
1239 return false;
1240 }
1241
1242 // compare returns
1243 Type tRet = tDesc.getReturnType();
1244 Type sRet = types.subst(sDesc.getReturnType(), sTypeParams, tTypeParams);
1245 if (tRet.containsAny(tTypeParams) && inferenceContext().free(sRet)) {
1246 return false;
1247 }
1248 MostSpecificFunctionReturnChecker msc = new MostSpecificFunctionReturnChecker(tRet, sRet);
1249 msc.scan(tree);
1250 return msc.result;
1251 }
1252
1253 /**
1254 * Tests whether one functional interface type can be considered more specific
1255 * than another unrelated functional interface type for the scanned expression.
1256 */
1257 class MostSpecificFunctionReturnChecker extends DeferredAttr.PolyScanner {
1258
1259 final Type tRet;
1260 final Type sRet;
1261 boolean result;
1262
1263 /** Parameters {@code t} and {@code s} are unrelated functional interface types. */
1264 MostSpecificFunctionReturnChecker(Type tRet, Type sRet) {
1265 this.tRet = tRet;
1266 this.sRet = sRet;
1267 result = true;
1268 }
1269
1270 @Override
1271 void skip(JCTree tree) {
1272 result &= false;
1273 }
1274
1275 @Override
1276 public void visitConditional(JCConditional tree) {
1277 scan(asExpr(tree.truepart));
1278 scan(asExpr(tree.falsepart));
1279 }
1280
1281 @Override
1282 public void visitReference(JCMemberReference tree) {
1283 if (sRet.hasTag(VOID)) {
1284 result &= true;
1285 } else if (tRet.hasTag(VOID)) {
1286 result &= false;
1287 } else if (tRet.isPrimitive() != sRet.isPrimitive()) {
1288 boolean retValIsPrimitive =
1289 tree.refPolyKind == PolyKind.STANDALONE &&
1290 tree.sym.type.getReturnType().isPrimitive();
1291 result &= (retValIsPrimitive == tRet.isPrimitive()) &&
1292 (retValIsPrimitive != sRet.isPrimitive());
1293 } else {
1294 result &= compatibleBySubtyping(tRet, sRet);
1295 }
1296 }
1297
1298 @Override
1299 public void visitParens(JCParens tree) {
1300 scan(asExpr(tree.expr));
1301 }
1302
1303 @Override
1304 public void visitLambda(JCLambda tree) {
1305 if (sRet.hasTag(VOID)) {
1306 result &= true;
1307 } else if (tRet.hasTag(VOID)) {
1308 result &= false;
1309 } else {
1310 List<JCExpression> lambdaResults = lambdaResults(tree);
1311 if (!lambdaResults.isEmpty() && unrelatedFunctionalInterfaces(tRet, sRet)) {
1312 for (JCExpression expr : lambdaResults) {
1313 result &= functionalInterfaceMostSpecific(tRet, sRet, expr);
1314 }
1315 } else if (!lambdaResults.isEmpty() && tRet.isPrimitive() != sRet.isPrimitive()) {
1316 for (JCExpression expr : lambdaResults) {
1317 boolean retValIsPrimitive = expr.isStandalone() && expr.type.isPrimitive();
1318 result &= (retValIsPrimitive == tRet.isPrimitive()) &&
1319 (retValIsPrimitive != sRet.isPrimitive());
1320 }
1321 } else {
1322 result &= compatibleBySubtyping(tRet, sRet);
1323 }
1324 }
1325 }
1326 //where
1327
1328 private List<JCExpression> lambdaResults(JCLambda lambda) {
1329 if (lambda.getBodyKind() == JCTree.JCLambda.BodyKind.EXPRESSION) {
1330 return List.of(asExpr((JCExpression) lambda.body));
1331 } else {
1332 final ListBuffer<JCExpression> buffer = new ListBuffer<>();
1333 DeferredAttr.LambdaReturnScanner lambdaScanner =
1334 new DeferredAttr.LambdaReturnScanner() {
1335 @Override
1336 public void visitReturn(JCReturn tree) {
1337 if (tree.expr != null) {
1338 buffer.append(asExpr(tree.expr));
1339 }
1340 }
1341 };
1342 lambdaScanner.scan(lambda.body);
1343 return buffer.toList();
1344 }
1345 }
1346
1347 private JCExpression asExpr(JCExpression expr) {
1348 if (expr.type.hasTag(DEFERRED)) {
1349 JCTree speculativeTree = ((DeferredType)expr.type).speculativeTree(deferredAttrContext);
1350 if (speculativeTree != deferredAttr.stuckTree) {
1351 expr = (JCExpression)speculativeTree;
1352 }
1353 }
1354 return expr;
1355 }
1356 }
1357
1358 }
1359
1360 public MethodCheck mostSpecificCheck(List<Type> actuals) {
1361 Assert.error("Cannot get here!");
1362 return null;
1363 }
1364 }
1365
1366 public static class InapplicableMethodException extends RuntimeException {
1367 private static final long serialVersionUID = 0;
1368
1369 JCDiagnostic diagnostic;
1370 JCDiagnostic.Factory diags;
1371
1372 InapplicableMethodException(JCDiagnostic.Factory diags) {
1373 this.diagnostic = null;
1374 this.diags = diags;
1375 }
1376 InapplicableMethodException setMessage() {
1377 return setMessage((JCDiagnostic)null);
1378 }
1379 InapplicableMethodException setMessage(String key) {
1380 return setMessage(key != null ? diags.fragment(key) : null);
1381 }
1382 InapplicableMethodException setMessage(String key, Object... args) {
1383 return setMessage(key != null ? diags.fragment(key, args) : null);
1384 }
1385 InapplicableMethodException setMessage(JCDiagnostic diag) {
1386 this.diagnostic = diag;
1387 return this;
1388 }
1389
1390 public JCDiagnostic getDiagnostic() {
1391 return diagnostic;
1392 }
1393 }
1394 private final InapplicableMethodException inapplicableMethodException;
1395
1396 /* ***************************************************************************
1397 * Symbol lookup
1398 * the following naming conventions for arguments are used
1399 *
1400 * env is the environment where the symbol was mentioned
1401 * site is the type of which the symbol is a member
1402 * name is the symbol's name
1403 * if no arguments are given
1404 * argtypes are the value arguments, if we search for a method
1405 *
1406 * If no symbol was found, a ResolveError detailing the problem is returned.
1407 ****************************************************************************/
1408
1409 /** Find field. Synthetic fields are always skipped.
1410 * @param env The current environment.
1411 * @param site The original type from where the selection takes place.
1412 * @param name The name of the field.
1413 * @param c The class to search for the field. This is always
1414 * a superclass or implemented interface of site's class.
1415 */
1416 Symbol findField(Env<AttrContext> env,
1417 Type site,
1418 Name name,
1419 TypeSymbol c) {
1420 while (c.type.hasTag(TYPEVAR))
1421 c = c.type.getUpperBound().tsym;
1422 Symbol bestSoFar = varNotFound;
1423 Symbol sym;
1424 for (Symbol s : c.members().getSymbolsByName(name)) {
1425 if (s.kind == VAR && (s.flags_field & SYNTHETIC) == 0) {
1426 return isAccessible(env, site, s)
1427 ? s : new AccessError(env, site, s);
1428 }
1429 }
1430 Type st = types.supertype(c.type);
1431 if (st != null && (st.hasTag(CLASS) || st.hasTag(TYPEVAR))) {
1432 sym = findField(env, site, name, st.tsym);
1433 bestSoFar = bestOf(bestSoFar, sym);
1434 }
1435 for (List<Type> l = types.interfaces(c.type);
1436 bestSoFar.kind != AMBIGUOUS && l.nonEmpty();
1437 l = l.tail) {
1438 sym = findField(env, site, name, l.head.tsym);
1439 if (bestSoFar.exists() && sym.exists() &&
1440 sym.owner != bestSoFar.owner)
1441 bestSoFar = new AmbiguityError(bestSoFar, sym);
1442 else
1443 bestSoFar = bestOf(bestSoFar, sym);
1444 }
1445 return bestSoFar;
1446 }
1447
1448 /** Resolve a field identifier, throw a fatal error if not found.
1449 * @param pos The position to use for error reporting.
1450 * @param env The environment current at the method invocation.
1451 * @param site The type of the qualifying expression, in which
1452 * identifier is searched.
1453 * @param name The identifier's name.
1454 */
1455 public VarSymbol resolveInternalField(DiagnosticPosition pos, Env<AttrContext> env,
1456 Type site, Name name) {
1457 Symbol sym = findField(env, site, name, site.tsym);
1458 if (sym.kind == VAR) return (VarSymbol)sym;
1459 else throw new FatalError(
1460 diags.fragment(Fragments.FatalErrCantLocateField(name)));
1461 }
1462
1463 /** Find unqualified variable or field with given name.
1464 * Synthetic fields always skipped.
1465 * @param env The current environment.
1466 * @param name The name of the variable or field.
1467 */
1468 Symbol findVar(Env<AttrContext> env, Name name) {
1469 Symbol bestSoFar = varNotFound;
1470 Env<AttrContext> env1 = env;
1471 boolean staticOnly = false;
1472 while (env1.outer != null) {
1473 Symbol sym = null;
1474 if (isStatic(env1)) staticOnly = true;
1475 for (Symbol s : env1.info.scope.getSymbolsByName(name)) {
1476 if (s.kind == VAR && (s.flags_field & SYNTHETIC) == 0) {
1477 sym = s;
1478 break;
1479 }
1480 }
1481 if (sym == null) {
1482 sym = findField(env1, env1.enclClass.sym.type, name, env1.enclClass.sym);
1483 }
1484 if (sym.exists()) {
1485 if (staticOnly &&
1486 sym.kind == VAR &&
1487 sym.owner.kind == TYP &&
1488 (sym.flags() & STATIC) == 0)
1489 return new StaticError(sym);
1490 else
1491 return sym;
1492 } else {
1493 bestSoFar = bestOf(bestSoFar, sym);
1494 }
1495
1496 if ((env1.enclClass.sym.flags() & STATIC) != 0) staticOnly = true;
1497 env1 = env1.outer;
1498 }
1499
1500 Symbol sym = findField(env, syms.predefClass.type, name, syms.predefClass);
1501 if (sym.exists())
1502 return sym;
1503 if (bestSoFar.exists())
1504 return bestSoFar;
1505
1506 Symbol origin = null;
1507 for (Scope sc : new Scope[] { env.toplevel.namedImportScope, env.toplevel.starImportScope }) {
1508 for (Symbol currentSymbol : sc.getSymbolsByName(name)) {
1509 if (currentSymbol.kind != VAR)
1510 continue;
1511 // invariant: sym.kind == Symbol.Kind.VAR
1512 if (!bestSoFar.kind.isResolutionError() &&
1513 currentSymbol.owner != bestSoFar.owner)
1514 return new AmbiguityError(bestSoFar, currentSymbol);
1515 else if (!bestSoFar.kind.betterThan(VAR)) {
1516 origin = sc.getOrigin(currentSymbol).owner;
1517 bestSoFar = isAccessible(env, origin.type, currentSymbol)
1518 ? currentSymbol : new AccessError(env, origin.type, currentSymbol);
1519 }
1520 }
1521 if (bestSoFar.exists()) break;
1522 }
1523 if (bestSoFar.kind == VAR && bestSoFar.owner.type != origin.type)
1524 return bestSoFar.clone(origin);
1525 else
1526 return bestSoFar;
1527 }
1528
1529 Warner noteWarner = new Warner();
1530
1531 /** Select the best method for a call site among two choices.
1532 * @param env The current environment.
1533 * @param site The original type from where the
1534 * selection takes place.
1535 * @param argtypes The invocation's value arguments,
1536 * @param typeargtypes The invocation's type arguments,
1537 * @param sym Proposed new best match.
1538 * @param bestSoFar Previously found best match.
1539 * @param allowBoxing Allow boxing conversions of arguments.
1540 * @param useVarargs Box trailing arguments into an array for varargs.
1541 */
1542 @SuppressWarnings("fallthrough")
1543 Symbol selectBest(Env<AttrContext> env,
1544 Type site,
1545 List<Type> argtypes,
1546 List<Type> typeargtypes,
1547 Symbol sym,
1548 Symbol bestSoFar,
1549 boolean allowBoxing,
1550 boolean useVarargs) {
1551 if (sym.kind == ERR ||
1552 (site.tsym != sym.owner && !sym.isInheritedIn(site.tsym, types)) ||
1553 !notOverriddenIn(site, sym)) {
1554 return bestSoFar;
1555 } else if (useVarargs && (sym.flags() & VARARGS) == 0) {
1556 return bestSoFar.kind.isResolutionError() ?
1557 new BadVarargsMethod((ResolveError)bestSoFar.baseSymbol()) :
1558 bestSoFar;
1559 }
1560 Assert.check(!sym.kind.isResolutionError());
1561 try {
1562 types.noWarnings.clear();
1563 Type mt = rawInstantiate(env, site, sym, null, argtypes, typeargtypes,
1564 allowBoxing, useVarargs, types.noWarnings);
1565 currentResolutionContext.addApplicableCandidate(sym, mt);
1566 } catch (InapplicableMethodException ex) {
1567 currentResolutionContext.addInapplicableCandidate(sym, ex.getDiagnostic());
1568 switch (bestSoFar.kind) {
1569 case ABSENT_MTH:
1570 return new InapplicableSymbolError(currentResolutionContext);
1571 case WRONG_MTH:
1572 bestSoFar = new InapplicableSymbolsError(currentResolutionContext);
1573 default:
1574 return bestSoFar;
1575 }
1576 }
1577 if (!isAccessible(env, site, sym)) {
1578 return (bestSoFar.kind == ABSENT_MTH)
1579 ? new AccessError(env, site, sym)
1580 : bestSoFar;
1581 }
1582 return (bestSoFar.kind.isResolutionError() && bestSoFar.kind != AMBIGUOUS)
1583 ? sym
1584 : mostSpecific(argtypes, sym, bestSoFar, env, site, useVarargs);
1585 }
1586
1587 /* Return the most specific of the two methods for a call,
1588 * given that both are accessible and applicable.
1589 * @param m1 A new candidate for most specific.
1590 * @param m2 The previous most specific candidate.
1591 * @param env The current environment.
1592 * @param site The original type from where the selection
1593 * takes place.
1594 * @param allowBoxing Allow boxing conversions of arguments.
1595 * @param useVarargs Box trailing arguments into an array for varargs.
1596 */
1597 Symbol mostSpecific(List<Type> argtypes, Symbol m1,
1598 Symbol m2,
1599 Env<AttrContext> env,
1600 final Type site,
1601 boolean useVarargs) {
1602 switch (m2.kind) {
1603 case MTH:
1604 if (m1 == m2) return m1;
1605 boolean m1SignatureMoreSpecific =
1606 signatureMoreSpecific(argtypes, env, site, m1, m2, useVarargs);
1607 boolean m2SignatureMoreSpecific =
1608 signatureMoreSpecific(argtypes, env, site, m2, m1, useVarargs);
1609 if (m1SignatureMoreSpecific && m2SignatureMoreSpecific) {
1610 Type mt1 = types.memberType(site, m1);
1611 Type mt2 = types.memberType(site, m2);
1612 if (!types.overrideEquivalent(mt1, mt2))
1613 return ambiguityError(m1, m2);
1614
1615 // same signature; select (a) the non-bridge method, or
1616 // (b) the one that overrides the other, or (c) the concrete
1617 // one, or (d) merge both abstract signatures
1618 if ((m1.flags() & BRIDGE) != (m2.flags() & BRIDGE))
1619 return ((m1.flags() & BRIDGE) != 0) ? m2 : m1;
1620
1621 if (m1.baseSymbol() == m2.baseSymbol()) {
1622 // this is the same imported symbol which has been cloned twice.
1623 // Return the first one (either will do).
1624 return m1;
1625 }
1626
1627 // if one overrides or hides the other, use it
1628 TypeSymbol m1Owner = (TypeSymbol)m1.owner;
1629 TypeSymbol m2Owner = (TypeSymbol)m2.owner;
1630 // the two owners can never be the same if the target methods are compiled from source,
1631 // but we need to protect against cases where the methods are defined in some classfile
1632 // and make sure we issue an ambiguity error accordingly (by skipping the logic below).
1633 if (m1Owner != m2Owner) {
1634 if (types.asSuper(m1Owner.type, m2Owner) != null &&
1635 ((m1.owner.flags_field & INTERFACE) == 0 ||
1636 (m2.owner.flags_field & INTERFACE) != 0) &&
1637 m1.overrides(m2, m1Owner, types, false))
1638 return m1;
1639 if (types.asSuper(m2Owner.type, m1Owner) != null &&
1640 ((m2.owner.flags_field & INTERFACE) == 0 ||
1641 (m1.owner.flags_field & INTERFACE) != 0) &&
1642 m2.overrides(m1, m2Owner, types, false))
1643 return m2;
1644 }
1645 boolean m1Abstract = (m1.flags() & ABSTRACT) != 0;
1646 boolean m2Abstract = (m2.flags() & ABSTRACT) != 0;
1647 if (m1Abstract && !m2Abstract) return m2;
1648 if (m2Abstract && !m1Abstract) return m1;
1649 // both abstract or both concrete
1650 return ambiguityError(m1, m2);
1651 }
1652 if (m1SignatureMoreSpecific) return m1;
1653 if (m2SignatureMoreSpecific) return m2;
1654 return ambiguityError(m1, m2);
1655 case AMBIGUOUS:
1656 //compare m1 to ambiguous methods in m2
1657 AmbiguityError e = (AmbiguityError)m2.baseSymbol();
1658 boolean m1MoreSpecificThanAnyAmbiguous = true;
1659 boolean allAmbiguousMoreSpecificThanM1 = true;
1660 for (Symbol s : e.ambiguousSyms) {
1661 Symbol moreSpecific = mostSpecific(argtypes, m1, s, env, site, useVarargs);
1662 m1MoreSpecificThanAnyAmbiguous &= moreSpecific == m1;
1663 allAmbiguousMoreSpecificThanM1 &= moreSpecific == s;
1664 }
1665 if (m1MoreSpecificThanAnyAmbiguous)
1666 return m1;
1667 //if m1 is more specific than some ambiguous methods, but other ambiguous methods are
1668 //more specific than m1, add it as a new ambiguous method:
1669 if (!allAmbiguousMoreSpecificThanM1)
1670 e.addAmbiguousSymbol(m1);
1671 return e;
1672 default:
1673 throw new AssertionError();
1674 }
1675 }
1676 //where
1677 private boolean signatureMoreSpecific(List<Type> actuals, Env<AttrContext> env, Type site, Symbol m1, Symbol m2, boolean useVarargs) {
1678 noteWarner.clear();
1679 int maxLength = Math.max(
1680 Math.max(m1.type.getParameterTypes().length(), actuals.length()),
1681 m2.type.getParameterTypes().length());
1682 MethodResolutionContext prevResolutionContext = currentResolutionContext;
1683 try {
1684 currentResolutionContext = new MethodResolutionContext();
1685 currentResolutionContext.step = prevResolutionContext.step;
1686 currentResolutionContext.methodCheck =
1687 prevResolutionContext.methodCheck.mostSpecificCheck(actuals);
1688 Type mst = instantiate(env, site, m2, null,
1689 adjustArgs(types.cvarLowerBounds(types.memberType(site, m1).getParameterTypes()), m1, maxLength, useVarargs), null,
1690 false, useVarargs, noteWarner);
1691 return mst != null &&
1692 !noteWarner.hasLint(Lint.LintCategory.UNCHECKED);
1693 } finally {
1694 currentResolutionContext = prevResolutionContext;
1695 }
1696 }
1697
1698 List<Type> adjustArgs(List<Type> args, Symbol msym, int length, boolean allowVarargs) {
1699 if ((msym.flags() & VARARGS) != 0 && allowVarargs) {
1700 Type varargsElem = types.elemtype(args.last());
1701 if (varargsElem == null) {
1702 Assert.error("Bad varargs = " + args.last() + " " + msym);
1703 }
1704 List<Type> newArgs = args.reverse().tail.prepend(varargsElem).reverse();
1705 while (newArgs.length() < length) {
1706 newArgs = newArgs.append(newArgs.last());
1707 }
1708 return newArgs;
1709 } else {
1710 return args;
1711 }
1712 }
1713 //where
1714 Symbol ambiguityError(Symbol m1, Symbol m2) {
1715 if (((m1.flags() | m2.flags()) & CLASH) != 0) {
1716 return (m1.flags() & CLASH) == 0 ? m1 : m2;
1717 } else {
1718 return new AmbiguityError(m1, m2);
1719 }
1720 }
1721
1722 Symbol findMethodInScope(Env<AttrContext> env,
1723 Type site,
1724 Name name,
1725 List<Type> argtypes,
1726 List<Type> typeargtypes,
1727 Scope sc,
1728 Symbol bestSoFar,
1729 boolean allowBoxing,
1730 boolean useVarargs,
1731 boolean abstractok) {
1732 for (Symbol s : sc.getSymbolsByName(name, new LookupFilter(abstractok))) {
1733 bestSoFar = selectBest(env, site, argtypes, typeargtypes, s,
1734 bestSoFar, allowBoxing, useVarargs);
1735 }
1736 return bestSoFar;
1737 }
1738 //where
1739 class LookupFilter implements Filter<Symbol> {
1740
1741 boolean abstractOk;
1742
1743 LookupFilter(boolean abstractOk) {
1744 this.abstractOk = abstractOk;
1745 }
1746
1747 public boolean accepts(Symbol s) {
1748 long flags = s.flags();
1749 return s.kind == MTH &&
1750 (flags & SYNTHETIC) == 0 &&
1751 (abstractOk ||
1752 (flags & DEFAULT) != 0 ||
1753 (flags & ABSTRACT) == 0);
1754 }
1755 }
1756
1757 /** Find best qualified method matching given name, type and value
1758 * arguments.
1759 * @param env The current environment.
1760 * @param site The original type from where the selection
1761 * takes place.
1762 * @param name The method's name.
1763 * @param argtypes The method's value arguments.
1764 * @param typeargtypes The method's type arguments
1765 * @param allowBoxing Allow boxing conversions of arguments.
1766 * @param useVarargs Box trailing arguments into an array for varargs.
1767 */
1768 Symbol findMethod(Env<AttrContext> env,
1769 Type site,
1770 Name name,
1771 List<Type> argtypes,
1772 List<Type> typeargtypes,
1773 boolean allowBoxing,
1774 boolean useVarargs) {
1775 Symbol bestSoFar = methodNotFound;
1776 bestSoFar = findMethod(env,
1777 site,
1778 name,
1779 argtypes,
1780 typeargtypes,
1781 site.tsym.type,
1782 bestSoFar,
1783 allowBoxing,
1784 useVarargs);
1785 return bestSoFar;
1786 }
1787 // where
1788 private Symbol findMethod(Env<AttrContext> env,
1789 Type site,
1790 Name name,
1791 List<Type> argtypes,
1792 List<Type> typeargtypes,
1793 Type intype,
1794 Symbol bestSoFar,
1795 boolean allowBoxing,
1796 boolean useVarargs) {
1797 @SuppressWarnings({"unchecked","rawtypes"})
1798 List<Type>[] itypes = (List<Type>[])new List[] { List.<Type>nil(), List.<Type>nil() };
1799
1800 InterfaceLookupPhase iphase = InterfaceLookupPhase.ABSTRACT_OK;
1801 for (TypeSymbol s : superclasses(intype)) {
1802 bestSoFar = findMethodInScope(env, site, name, argtypes, typeargtypes,
1803 s.members(), bestSoFar, allowBoxing, useVarargs, true);
1804 if (name == names.init) return bestSoFar;
1805 iphase = (iphase == null) ? null : iphase.update(s, this);
1806 if (iphase != null) {
1807 for (Type itype : types.interfaces(s.type)) {
1808 itypes[iphase.ordinal()] = types.union(types.closure(itype), itypes[iphase.ordinal()]);
1809 }
1810 }
1811 }
1812
1813 Symbol concrete = bestSoFar.kind.isValid() &&
1814 (bestSoFar.flags() & ABSTRACT) == 0 ?
1815 bestSoFar : methodNotFound;
1816
1817 for (InterfaceLookupPhase iphase2 : InterfaceLookupPhase.values()) {
1818 //keep searching for abstract methods
1819 for (Type itype : itypes[iphase2.ordinal()]) {
1820 if (!itype.isInterface()) continue; //skip j.l.Object (included by Types.closure())
1821 if (iphase2 == InterfaceLookupPhase.DEFAULT_OK &&
1822 (itype.tsym.flags() & DEFAULT) == 0) continue;
1823 bestSoFar = findMethodInScope(env, site, name, argtypes, typeargtypes,
1824 itype.tsym.members(), bestSoFar, allowBoxing, useVarargs, true);
1825 if (concrete != bestSoFar &&
1826 concrete.kind.isValid() &&
1827 bestSoFar.kind.isValid() &&
1828 types.isSubSignature(concrete.type, bestSoFar.type)) {
1829 //this is an hack - as javac does not do full membership checks
1830 //most specific ends up comparing abstract methods that might have
1831 //been implemented by some concrete method in a subclass and,
1832 //because of raw override, it is possible for an abstract method
1833 //to be more specific than the concrete method - so we need
1834 //to explicitly call that out (see CR 6178365)
1835 bestSoFar = concrete;
1836 }
1837 }
1838 }
1839 return bestSoFar;
1840 }
1841
1842 enum InterfaceLookupPhase {
1843 ABSTRACT_OK() {
1844 @Override
1845 InterfaceLookupPhase update(Symbol s, Resolve rs) {
1846 //We should not look for abstract methods if receiver is a concrete class
1847 //(as concrete classes are expected to implement all abstracts coming
1848 //from superinterfaces)
1849 if ((s.flags() & (ABSTRACT | INTERFACE | ENUM)) != 0) {
1850 return this;
1851 } else {
1852 return DEFAULT_OK;
1853 }
1854 }
1855 },
1856 DEFAULT_OK() {
1857 @Override
1858 InterfaceLookupPhase update(Symbol s, Resolve rs) {
1859 return this;
1860 }
1861 };
1862
1863 abstract InterfaceLookupPhase update(Symbol s, Resolve rs);
1864 }
1865
1866 /**
1867 * Return an Iterable object to scan the superclasses of a given type.
1868 * It's crucial that the scan is done lazily, as we don't want to accidentally
1869 * access more supertypes than strictly needed (as this could trigger completion
1870 * errors if some of the not-needed supertypes are missing/ill-formed).
1871 */
1872 Iterable<TypeSymbol> superclasses(final Type intype) {
1873 return () -> new Iterator<TypeSymbol>() {
1874
1875 List<TypeSymbol> seen = List.nil();
1876 TypeSymbol currentSym = symbolFor(intype);
1877 TypeSymbol prevSym = null;
1878
1879 public boolean hasNext() {
1880 if (currentSym == syms.noSymbol) {
1881 currentSym = symbolFor(types.supertype(prevSym.type));
1882 }
1883 return currentSym != null;
1884 }
1885
1886 public TypeSymbol next() {
1887 prevSym = currentSym;
1888 currentSym = syms.noSymbol;
1889 Assert.check(prevSym != null || prevSym != syms.noSymbol);
1890 return prevSym;
1891 }
1892
1893 public void remove() {
1894 throw new UnsupportedOperationException();
1895 }
1896
1897 TypeSymbol symbolFor(Type t) {
1898 if (!t.hasTag(CLASS) &&
1899 !t.hasTag(TYPEVAR)) {
1900 return null;
1901 }
1902 t = types.skipTypeVars(t, false);
1903 if (seen.contains(t.tsym)) {
1904 //degenerate case in which we have a circular
1905 //class hierarchy - because of ill-formed classfiles
1906 return null;
1907 }
1908 seen = seen.prepend(t.tsym);
1909 return t.tsym;
1910 }
1911 };
1912 }
1913
1914 /** Find unqualified method matching given name, type and value arguments.
1915 * @param env The current environment.
1916 * @param name The method's name.
1917 * @param argtypes The method's value arguments.
1918 * @param typeargtypes The method's type arguments.
1919 * @param allowBoxing Allow boxing conversions of arguments.
1920 * @param useVarargs Box trailing arguments into an array for varargs.
1921 */
1922 Symbol findFun(Env<AttrContext> env, Name name,
1923 List<Type> argtypes, List<Type> typeargtypes,
1924 boolean allowBoxing, boolean useVarargs) {
1925 Symbol bestSoFar = methodNotFound;
1926 Env<AttrContext> env1 = env;
1927 boolean staticOnly = false;
1928 while (env1.outer != null) {
1929 if (isStatic(env1)) staticOnly = true;
1930 Assert.check(env1.info.preferredTreeForDiagnostics == null);
1931 env1.info.preferredTreeForDiagnostics = env.tree;
1932 try {
1933 Symbol sym = findMethod(
1934 env1, env1.enclClass.sym.type, name, argtypes, typeargtypes,
1935 allowBoxing, useVarargs);
1936 if (sym.exists()) {
1937 if (staticOnly &&
1938 sym.kind == MTH &&
1939 sym.owner.kind == TYP &&
1940 (sym.flags() & STATIC) == 0) return new StaticError(sym);
1941 else return sym;
1942 } else {
1943 bestSoFar = bestOf(bestSoFar, sym);
1944 }
1945 } finally {
1946 env1.info.preferredTreeForDiagnostics = null;
1947 }
1948 if ((env1.enclClass.sym.flags() & STATIC) != 0) staticOnly = true;
1949 env1 = env1.outer;
1950 }
1951
1952 Symbol sym = findMethod(env, syms.predefClass.type, name, argtypes,
1953 typeargtypes, allowBoxing, useVarargs);
1954 if (sym.exists())
1955 return sym;
1956
1957 for (Symbol currentSym : env.toplevel.namedImportScope.getSymbolsByName(name)) {
1958 Symbol origin = env.toplevel.namedImportScope.getOrigin(currentSym).owner;
1959 if (currentSym.kind == MTH) {
1960 if (currentSym.owner.type != origin.type)
1961 currentSym = currentSym.clone(origin);
1962 if (!isAccessible(env, origin.type, currentSym))
1963 currentSym = new AccessError(env, origin.type, currentSym);
1964 bestSoFar = selectBest(env, origin.type,
1965 argtypes, typeargtypes,
1966 currentSym, bestSoFar,
1967 allowBoxing, useVarargs);
1968 }
1969 }
1970 if (bestSoFar.exists())
1971 return bestSoFar;
1972
1973 for (Symbol currentSym : env.toplevel.starImportScope.getSymbolsByName(name)) {
1974 Symbol origin = env.toplevel.starImportScope.getOrigin(currentSym).owner;
1975 if (currentSym.kind == MTH) {
1976 if (currentSym.owner.type != origin.type)
1977 currentSym = currentSym.clone(origin);
1978 if (!isAccessible(env, origin.type, currentSym))
1979 currentSym = new AccessError(env, origin.type, currentSym);
1980 bestSoFar = selectBest(env, origin.type,
1981 argtypes, typeargtypes,
1982 currentSym, bestSoFar,
1983 allowBoxing, useVarargs);
1984 }
1985 }
1986 return bestSoFar;
1987 }
1988
1989 /** Load toplevel or member class with given fully qualified name and
1990 * verify that it is accessible.
1991 * @param env The current environment.
1992 * @param name The fully qualified name of the class to be loaded.
1993 */
1994 Symbol loadClass(Env<AttrContext> env, Name name, RecoveryLoadClass recoveryLoadClass) {
1995 try {
1996 ClassSymbol c = finder.loadClass(env.toplevel.modle, name);
1997 return isAccessible(env, c) ? c : new AccessError(env, null, c);
1998 } catch (ClassFinder.BadClassFile err) {
1999 throw err;
2000 } catch (CompletionFailure ex) {
2001 Symbol candidate = recoveryLoadClass.loadClass(env, name);
2002
2003 if (candidate != null) {
2004 return candidate;
2005 }
2006
2007 return typeNotFound;
2008 }
2009 }
2010
2011 public interface RecoveryLoadClass {
2012 Symbol loadClass(Env<AttrContext> env, Name name);
2013 }
2014
2015 private final RecoveryLoadClass noRecovery = (env, name) -> null;
2016
2017 private final RecoveryLoadClass doRecoveryLoadClass = new RecoveryLoadClass() {
2018 @Override public Symbol loadClass(Env<AttrContext> env, Name name) {
2019 List<Name> candidates = Convert.classCandidates(name);
2020 return lookupInvisibleSymbol(env, name,
2021 n -> () -> createCompoundIterator(candidates,
2022 c -> syms.getClassesForName(c)
2023 .iterator()),
2024 (ms, n) -> {
2025 for (Name candidate : candidates) {
2026 try {
2027 return finder.loadClass(ms, candidate);
2028 } catch (CompletionFailure cf) {
2029 //ignore
2030 }
2031 }
2032 return null;
2033 }, sym -> sym.kind == Kind.TYP, false, typeNotFound);
2034 }
2035 };
2036
2037 private final RecoveryLoadClass namedImportScopeRecovery = (env, name) -> {
2038 Scope importScope = env.toplevel.namedImportScope;
2039 Symbol existing = importScope.findFirst(Convert.shortName(name),
2040 sym -> sym.kind == TYP && sym.flatName() == name);
2041
2042 if (existing != null) {
2043 return new InvisibleSymbolError(env, true, existing);
2044 }
2045 return null;
2046 };
2047
2048 private final RecoveryLoadClass starImportScopeRecovery = (env, name) -> {
2049 Scope importScope = env.toplevel.starImportScope;
2050 Symbol existing = importScope.findFirst(Convert.shortName(name),
2051 sym -> sym.kind == TYP && sym.flatName() == name);
2052
2053 if (existing != null) {
2054 try {
2055 existing = finder.loadClass(existing.packge().modle, name);
2056
2057 return new InvisibleSymbolError(env, true, existing);
2058 } catch (CompletionFailure cf) {
2059 //ignore
2060 }
2061 }
2062
2063 return null;
2064 };
2065
2066 Symbol lookupPackage(Env<AttrContext> env, Name name) {
2067 PackageSymbol pack = syms.lookupPackage(env.toplevel.modle, name);
2068
2069 if (allowModules && isImportOnDemand(env, name)) {
2070 pack.complete();
2071 if (!pack.exists()) {
2072 Name nameAndDot = name.append('.', names.empty);
2073 boolean prefixOfKnown =
2074 env.toplevel.modle.visiblePackages.values()
2075 .stream()
2076 .anyMatch(p -> p.fullname.startsWith(nameAndDot));
2077
2078 return lookupInvisibleSymbol(env, name, syms::getPackagesForName, syms::enterPackage, sym -> {
2079 sym.complete();
2080 return sym.exists();
2081 }, prefixOfKnown, pack);
2082 }
2083 }
2084
2085 return pack;
2086 }
2087
2088 private boolean isImportOnDemand(Env<AttrContext> env, Name name) {
2089 if (!env.tree.hasTag(IMPORT))
2090 return false;
2091
2092 JCTree qualid = ((JCImport) env.tree).qualid;
2093
2094 if (!qualid.hasTag(SELECT))
2095 return false;
2096
2097 if (TreeInfo.name(qualid) != names.asterisk)
2098 return false;
2099
2100 return TreeInfo.fullName(((JCFieldAccess) qualid).selected) == name;
2101 }
2102
2103 private <S extends Symbol> Symbol lookupInvisibleSymbol(Env<AttrContext> env,
2104 Name name,
2105 Function<Name, Iterable<S>> get,
2106 BiFunction<ModuleSymbol, Name, S> load,
2107 Predicate<S> validate,
2108 boolean suppressError,
2109 Symbol defaultResult) {
2110 //even if a class/package cannot be found in the current module and among packages in modules
2111 //it depends on that are exported for any or this module, the class/package may exist internally
2112 //in some of these modules, or may exist in a module on which this module does not depend.
2113 //Provide better diagnostic in such cases by looking for the class in any module:
2114 Iterable<? extends S> candidates = get.apply(name);
2115
2116 for (S sym : candidates) {
2117 if (validate.test(sym))
2118 return createInvisibleSymbolError(env, suppressError, sym);
2119 }
2120
2121 Set<ModuleSymbol> recoverableModules = new HashSet<>(syms.getAllModules());
2122
2123 recoverableModules.remove(env.toplevel.modle);
2124
2125 for (ModuleSymbol ms : recoverableModules) {
2126 //avoid overly eager completing classes from source-based modules, as those
2127 //may not be completable with the current compiler settings:
2128 if (ms.sourceLocation == null) {
2129 if (ms.classLocation == null) {
2130 ms = moduleFinder.findModule(ms);
2131 }
2132
2133 if (ms.kind != ERR) {
2134 S sym = load.apply(ms, name);
2135
2136 if (sym != null && validate.test(sym)) {
2137 return createInvisibleSymbolError(env, suppressError, sym);
2138 }
2139 }
2140 }
2141 }
2142
2143 return defaultResult;
2144 }
2145
2146 private Symbol createInvisibleSymbolError(Env<AttrContext> env, boolean suppressError, Symbol sym) {
2147 if (symbolPackageVisible(env, sym)) {
2148 return new AccessError(env, null, sym);
2149 } else {
2150 return new InvisibleSymbolError(env, suppressError, sym);
2151 }
2152 }
2153
2154 private boolean symbolPackageVisible(Env<AttrContext> env, Symbol sym) {
2155 ModuleSymbol envMod = env.toplevel.modle;
2156 PackageSymbol symPack = sym.packge();
2157 return envMod == symPack.modle ||
2158 envMod.visiblePackages.containsKey(symPack.fullname);
2159 }
2160
2161 /**
2162 * Find a type declared in a scope (not inherited). Return null
2163 * if none is found.
2164 * @param env The current environment.
2165 * @param site The original type from where the selection takes
2166 * place.
2167 * @param name The type's name.
2168 * @param c The class to search for the member type. This is
2169 * always a superclass or implemented interface of
2170 * site's class.
2171 */
2172 Symbol findImmediateMemberType(Env<AttrContext> env,
2173 Type site,
2174 Name name,
2175 TypeSymbol c) {
2176 for (Symbol sym : c.members().getSymbolsByName(name)) {
2177 if (sym.kind == TYP) {
2178 return isAccessible(env, site, sym)
2179 ? sym
2180 : new AccessError(env, site, sym);
2181 }
2182 }
2183 return typeNotFound;
2184 }
2185
2186 /** Find a member type inherited from a superclass or interface.
2187 * @param env The current environment.
2188 * @param site The original type from where the selection takes
2189 * place.
2190 * @param name The type's name.
2191 * @param c The class to search for the member type. This is
2192 * always a superclass or implemented interface of
2193 * site's class.
2194 */
2195 Symbol findInheritedMemberType(Env<AttrContext> env,
2196 Type site,
2197 Name name,
2198 TypeSymbol c) {
2199 Symbol bestSoFar = typeNotFound;
2200 Symbol sym;
2201 Type st = types.supertype(c.type);
2202 if (st != null && st.hasTag(CLASS)) {
2203 sym = findMemberType(env, site, name, st.tsym);
2204 bestSoFar = bestOf(bestSoFar, sym);
2205 }
2206 for (List<Type> l = types.interfaces(c.type);
2207 bestSoFar.kind != AMBIGUOUS && l.nonEmpty();
2208 l = l.tail) {
2209 sym = findMemberType(env, site, name, l.head.tsym);
2210 if (!bestSoFar.kind.isResolutionError() &&
2211 !sym.kind.isResolutionError() &&
2212 sym.owner != bestSoFar.owner)
2213 bestSoFar = new AmbiguityError(bestSoFar, sym);
2214 else
2215 bestSoFar = bestOf(bestSoFar, sym);
2216 }
2217 return bestSoFar;
2218 }
2219
2220 /** Find qualified member type.
2221 * @param env The current environment.
2222 * @param site The original type from where the selection takes
2223 * place.
2224 * @param name The type's name.
2225 * @param c The class to search for the member type. This is
2226 * always a superclass or implemented interface of
2227 * site's class.
2228 */
2229 Symbol findMemberType(Env<AttrContext> env,
2230 Type site,
2231 Name name,
2232 TypeSymbol c) {
2233 Symbol sym = findImmediateMemberType(env, site, name, c);
2234
2235 if (sym != typeNotFound)
2236 return sym;
2237
2238 return findInheritedMemberType(env, site, name, c);
2239
2240 }
2241
2242 /** Find a global type in given scope and load corresponding class.
2243 * @param env The current environment.
2244 * @param scope The scope in which to look for the type.
2245 * @param name The type's name.
2246 */
2247 Symbol findGlobalType(Env<AttrContext> env, Scope scope, Name name, RecoveryLoadClass recoveryLoadClass) {
2248 Symbol bestSoFar = typeNotFound;
2249 for (Symbol s : scope.getSymbolsByName(name)) {
2250 Symbol sym = loadClass(env, s.flatName(), recoveryLoadClass);
2251 if (bestSoFar.kind == TYP && sym.kind == TYP &&
2252 bestSoFar != sym)
2253 return new AmbiguityError(bestSoFar, sym);
2254 else
2255 bestSoFar = bestOf(bestSoFar, sym);
2256 }
2257 return bestSoFar;
2258 }
2259
2260 Symbol findTypeVar(Env<AttrContext> env, Name name, boolean staticOnly) {
2261 for (Symbol sym : env.info.scope.getSymbolsByName(name)) {
2262 if (sym.kind == TYP) {
2263 if (staticOnly &&
2264 sym.type.hasTag(TYPEVAR) &&
2265 sym.owner.kind == TYP)
2266 return new StaticError(sym);
2267 return sym;
2268 }
2269 }
2270 return typeNotFound;
2271 }
2272
2273 /** Find an unqualified type symbol.
2274 * @param env The current environment.
2275 * @param name The type's name.
2276 */
2277 Symbol findType(Env<AttrContext> env, Name name) {
2278 if (name == names.empty)
2279 return typeNotFound; // do not allow inadvertent "lookup" of anonymous types
2280 Symbol bestSoFar = typeNotFound;
2281 Symbol sym;
2282 boolean staticOnly = false;
2283 for (Env<AttrContext> env1 = env; env1.outer != null; env1 = env1.outer) {
2284 if (isStatic(env1)) staticOnly = true;
2285 // First, look for a type variable and the first member type
2286 final Symbol tyvar = findTypeVar(env1, name, staticOnly);
2287 sym = findImmediateMemberType(env1, env1.enclClass.sym.type,
2288 name, env1.enclClass.sym);
2289
2290 // Return the type variable if we have it, and have no
2291 // immediate member, OR the type variable is for a method.
2292 if (tyvar != typeNotFound) {
2293 if (env.baseClause || sym == typeNotFound ||
2294 (tyvar.kind == TYP && tyvar.exists() &&
2295 tyvar.owner.kind == MTH)) {
2296 return tyvar;
2297 }
2298 }
2299
2300 // If the environment is a class def, finish up,
2301 // otherwise, do the entire findMemberType
2302 if (sym == typeNotFound)
2303 sym = findInheritedMemberType(env1, env1.enclClass.sym.type,
2304 name, env1.enclClass.sym);
2305
2306 if (staticOnly && sym.kind == TYP &&
2307 sym.type.hasTag(CLASS) &&
2308 sym.type.getEnclosingType().hasTag(CLASS) &&
2309 env1.enclClass.sym.type.isParameterized() &&
2310 sym.type.getEnclosingType().isParameterized())
2311 return new StaticError(sym);
2312 else if (sym.exists()) return sym;
2313 else bestSoFar = bestOf(bestSoFar, sym);
2314
2315 JCClassDecl encl = env1.baseClause ? (JCClassDecl)env1.tree : env1.enclClass;
2316 if ((encl.sym.flags() & STATIC) != 0)
2317 staticOnly = true;
2318 }
2319
2320 if (!env.tree.hasTag(IMPORT)) {
2321 sym = findGlobalType(env, env.toplevel.namedImportScope, name, namedImportScopeRecovery);
2322 if (sym.exists()) return sym;
2323 else bestSoFar = bestOf(bestSoFar, sym);
2324
2325 sym = findGlobalType(env, env.toplevel.packge.members(), name, noRecovery);
2326 if (sym.exists()) return sym;
2327 else bestSoFar = bestOf(bestSoFar, sym);
2328
2329 sym = findGlobalType(env, env.toplevel.starImportScope, name, starImportScopeRecovery);
2330 if (sym.exists()) return sym;
2331 else bestSoFar = bestOf(bestSoFar, sym);
2332 }
2333
2334 return bestSoFar;
2335 }
2336
2337 /** Find an unqualified identifier which matches a specified kind set.
2338 * @param env The current environment.
2339 * @param name The identifier's name.
2340 * @param kind Indicates the possible symbol kinds
2341 * (a subset of VAL, TYP, PCK).
2342 */
2343 Symbol findIdent(Env<AttrContext> env, Name name, KindSelector kind) {
2344 return checkVarType(findIdentInternal(env, name, kind), name);
2345 }
2346
2347 Symbol findIdentInternal(Env<AttrContext> env, Name name, KindSelector kind) {
2348 Symbol bestSoFar = typeNotFound;
2349 Symbol sym;
2350
2351 if (kind.contains(KindSelector.VAL)) {
2352 sym = findVar(env, name);
2353 if (sym.exists()) return sym;
2354 else bestSoFar = bestOf(bestSoFar, sym);
2355 }
2356
2357 if (kind.contains(KindSelector.TYP)) {
2358 sym = findType(env, name);
2359
2360 if (sym.exists()) return sym;
2361 else bestSoFar = bestOf(bestSoFar, sym);
2362 }
2363
2364 if (kind.contains(KindSelector.PCK))
2365 return lookupPackage(env, name);
2366 else return bestSoFar;
2367 }
2368
2369 /** Find an identifier in a package which matches a specified kind set.
2370 * @param env The current environment.
2371 * @param name The identifier's name.
2372 * @param kind Indicates the possible symbol kinds
2373 * (a nonempty subset of TYP, PCK).
2374 */
2375 Symbol findIdentInPackage(Env<AttrContext> env, TypeSymbol pck,
2376 Name name, KindSelector kind) {
2377 return checkVarType(findIdentInPackageInternal(env, pck, name, kind), name);
2378 }
2379
2380 Symbol findIdentInPackageInternal(Env<AttrContext> env, TypeSymbol pck,
2381 Name name, KindSelector kind) {
2382 Name fullname = TypeSymbol.formFullName(name, pck);
2383 Symbol bestSoFar = typeNotFound;
2384 if (kind.contains(KindSelector.TYP)) {
2385 RecoveryLoadClass recoveryLoadClass =
2386 allowModules && !kind.contains(KindSelector.PCK) &&
2387 !pck.exists() && !env.info.isSpeculative ?
2388 doRecoveryLoadClass : noRecovery;
2389 Symbol sym = loadClass(env, fullname, recoveryLoadClass);
2390 if (sym.exists()) {
2391 // don't allow programs to use flatnames
2392 if (name == sym.name) return sym;
2393 }
2394 else bestSoFar = bestOf(bestSoFar, sym);
2395 }
2396 if (kind.contains(KindSelector.PCK)) {
2397 return lookupPackage(env, fullname);
2398 }
2399 return bestSoFar;
2400 }
2401
2402 /** Find an identifier among the members of a given type `site'.
2403 * @param env The current environment.
2404 * @param site The type containing the symbol to be found.
2405 * @param name The identifier's name.
2406 * @param kind Indicates the possible symbol kinds
2407 * (a subset of VAL, TYP).
2408 */
2409 Symbol findIdentInType(Env<AttrContext> env, Type site,
2410 Name name, KindSelector kind) {
2411 return checkVarType(findIdentInTypeInternal(env, site, name, kind), name);
2412 }
2413
2414 Symbol findIdentInTypeInternal(Env<AttrContext> env, Type site,
2415 Name name, KindSelector kind) {
2416 Symbol bestSoFar = typeNotFound;
2417 Symbol sym;
2418 if (kind.contains(KindSelector.VAL)) {
2419 sym = findField(env, site, name, site.tsym);
2420 if (sym.exists()) return sym;
2421 else bestSoFar = bestOf(bestSoFar, sym);
2422 }
2423
2424 if (kind.contains(KindSelector.TYP)) {
2425 sym = findMemberType(env, site, name, site.tsym);
2426 if (sym.exists()) return sym;
2427 else bestSoFar = bestOf(bestSoFar, sym);
2428 }
2429 return bestSoFar;
2430 }
2431
2432 private Symbol checkVarType(Symbol bestSoFar, Name name) {
2433 if (allowLocalVariableTypeInference && name.equals(names.var) &&
2434 (bestSoFar.kind == TYP || bestSoFar.kind == ABSENT_TYP)) {
2435 bestSoFar = new BadVarTypeError();
2436 }
2437 return bestSoFar;
2438 }
2439
2440 /* ***************************************************************************
2441 * Access checking
2442 * The following methods convert ResolveErrors to ErrorSymbols, issuing
2443 * an error message in the process
2444 ****************************************************************************/
2445
2446 /** If `sym' is a bad symbol: report error and return errSymbol
2447 * else pass through unchanged,
2448 * additional arguments duplicate what has been used in trying to find the
2449 * symbol {@literal (--> flyweight pattern)}. This improves performance since we
2450 * expect misses to happen frequently.
2451 *
2452 * @param sym The symbol that was found, or a ResolveError.
2453 * @param pos The position to use for error reporting.
2454 * @param location The symbol the served as a context for this lookup
2455 * @param site The original type from where the selection took place.
2456 * @param name The symbol's name.
2457 * @param qualified Did we get here through a qualified expression resolution?
2458 * @param argtypes The invocation's value arguments,
2459 * if we looked for a method.
2460 * @param typeargtypes The invocation's type arguments,
2461 * if we looked for a method.
2462 * @param logResolveHelper helper class used to log resolve errors
2463 */
2464 Symbol accessInternal(Symbol sym,
2465 DiagnosticPosition pos,
2466 Symbol location,
2467 Type site,
2468 Name name,
2469 boolean qualified,
2470 List<Type> argtypes,
2471 List<Type> typeargtypes,
2472 LogResolveHelper logResolveHelper) {
2473 if (sym.kind.isResolutionError()) {
2474 ResolveError errSym = (ResolveError)sym.baseSymbol();
2475 sym = errSym.access(name, qualified ? site.tsym : syms.noSymbol);
2476 argtypes = logResolveHelper.getArgumentTypes(errSym, sym, name, argtypes);
2477 if (logResolveHelper.resolveDiagnosticNeeded(site, argtypes, typeargtypes)) {
2478 logResolveError(errSym, pos, location, site, name, argtypes, typeargtypes);
2479 }
2480 }
2481 return sym;
2482 }
2483
2484 /**
2485 * Variant of the generalized access routine, to be used for generating method
2486 * resolution diagnostics
2487 */
2488 Symbol accessMethod(Symbol sym,
2489 DiagnosticPosition pos,
2490 Symbol location,
2491 Type site,
2492 Name name,
2493 boolean qualified,
2494 List<Type> argtypes,
2495 List<Type> typeargtypes) {
2496 return accessInternal(sym, pos, location, site, name, qualified, argtypes, typeargtypes, methodLogResolveHelper);
2497 }
2498
2499 /** Same as original accessMethod(), but without location.
2500 */
2501 Symbol accessMethod(Symbol sym,
2502 DiagnosticPosition pos,
2503 Type site,
2504 Name name,
2505 boolean qualified,
2506 List<Type> argtypes,
2507 List<Type> typeargtypes) {
2508 return accessMethod(sym, pos, site.tsym, site, name, qualified, argtypes, typeargtypes);
2509 }
2510
2511 /**
2512 * Variant of the generalized access routine, to be used for generating variable,
2513 * type resolution diagnostics
2514 */
2515 Symbol accessBase(Symbol sym,
2516 DiagnosticPosition pos,
2517 Symbol location,
2518 Type site,
2519 Name name,
2520 boolean qualified) {
2521 return accessInternal(sym, pos, location, site, name, qualified, List.nil(), null, basicLogResolveHelper);
2522 }
2523
2524 /** Same as original accessBase(), but without location.
2525 */
2526 Symbol accessBase(Symbol sym,
2527 DiagnosticPosition pos,
2528 Type site,
2529 Name name,
2530 boolean qualified) {
2531 return accessBase(sym, pos, site.tsym, site, name, qualified);
2532 }
2533
2534 interface LogResolveHelper {
2535 boolean resolveDiagnosticNeeded(Type site, List<Type> argtypes, List<Type> typeargtypes);
2536 List<Type> getArgumentTypes(ResolveError errSym, Symbol accessedSym, Name name, List<Type> argtypes);
2537 }
2538
2539 LogResolveHelper basicLogResolveHelper = new LogResolveHelper() {
2540 public boolean resolveDiagnosticNeeded(Type site, List<Type> argtypes, List<Type> typeargtypes) {
2541 return !site.isErroneous();
2542 }
2543 public List<Type> getArgumentTypes(ResolveError errSym, Symbol accessedSym, Name name, List<Type> argtypes) {
2544 return argtypes;
2545 }
2546 };
2547
2548 LogResolveHelper methodLogResolveHelper = new LogResolveHelper() {
2549 public boolean resolveDiagnosticNeeded(Type site, List<Type> argtypes, List<Type> typeargtypes) {
2550 return !site.isErroneous() &&
2551 !Type.isErroneous(argtypes) &&
2552 (typeargtypes == null || !Type.isErroneous(typeargtypes));
2553 }
2554 public List<Type> getArgumentTypes(ResolveError errSym, Symbol accessedSym, Name name, List<Type> argtypes) {
2555 return argtypes.map(new ResolveDeferredRecoveryMap(AttrMode.SPECULATIVE, accessedSym, currentResolutionContext.step));
2556 }
2557 };
2558
2559 class ResolveDeferredRecoveryMap extends DeferredAttr.RecoveryDeferredTypeMap {
2560
2561 public ResolveDeferredRecoveryMap(AttrMode mode, Symbol msym, MethodResolutionPhase step) {
2562 deferredAttr.super(mode, msym, step);
2563 }
2564
2565 @Override
2566 protected Type typeOf(DeferredType dt) {
2567 Type res = super.typeOf(dt);
2568 if (!res.isErroneous()) {
2569 switch (TreeInfo.skipParens(dt.tree).getTag()) {
2570 case LAMBDA:
2571 case REFERENCE:
2572 return dt;
2573 case CONDEXPR:
2574 return res == Type.recoveryType ?
2575 dt : res;
2576 }
2577 }
2578 return res;
2579 }
2580 }
2581
2582 /** Check that sym is not an abstract method.
2583 */
2584 void checkNonAbstract(DiagnosticPosition pos, Symbol sym) {
2585 if ((sym.flags() & ABSTRACT) != 0 && (sym.flags() & DEFAULT) == 0)
2586 log.error(pos,
2587 Errors.AbstractCantBeAccessedDirectly(kindName(sym),sym, sym.location()));
2588 }
2589
2590 /* ***************************************************************************
2591 * Name resolution
2592 * Naming conventions are as for symbol lookup
2593 * Unlike the find... methods these methods will report access errors
2594 ****************************************************************************/
2595
2596 /** Resolve an unqualified (non-method) identifier.
2597 * @param pos The position to use for error reporting.
2598 * @param env The environment current at the identifier use.
2599 * @param name The identifier's name.
2600 * @param kind The set of admissible symbol kinds for the identifier.
2601 */
2602 Symbol resolveIdent(DiagnosticPosition pos, Env<AttrContext> env,
2603 Name name, KindSelector kind) {
2604 return accessBase(
2605 findIdent(env, name, kind),
2606 pos, env.enclClass.sym.type, name, false);
2607 }
2608
2609 /** Resolve an unqualified method identifier.
2610 * @param pos The position to use for error reporting.
2611 * @param env The environment current at the method invocation.
2612 * @param name The identifier's name.
2613 * @param argtypes The types of the invocation's value arguments.
2614 * @param typeargtypes The types of the invocation's type arguments.
2615 */
2616 Symbol resolveMethod(DiagnosticPosition pos,
2617 Env<AttrContext> env,
2618 Name name,
2619 List<Type> argtypes,
2620 List<Type> typeargtypes) {
2621 return lookupMethod(env, pos, env.enclClass.sym, resolveMethodCheck,
2622 new BasicLookupHelper(name, env.enclClass.sym.type, argtypes, typeargtypes) {
2623 @Override
2624 Symbol doLookup(Env<AttrContext> env, MethodResolutionPhase phase) {
2625 return findFun(env, name, argtypes, typeargtypes,
2626 phase.isBoxingRequired(),
2627 phase.isVarargsRequired());
2628 }});
2629 }
2630
2631 /** Resolve a qualified method identifier
2632 * @param pos The position to use for error reporting.
2633 * @param env The environment current at the method invocation.
2634 * @param site The type of the qualifying expression, in which
2635 * identifier is searched.
2636 * @param name The identifier's name.
2637 * @param argtypes The types of the invocation's value arguments.
2638 * @param typeargtypes The types of the invocation's type arguments.
2639 */
2640 Symbol resolveQualifiedMethod(DiagnosticPosition pos, Env<AttrContext> env,
2641 Type site, Name name, List<Type> argtypes,
2642 List<Type> typeargtypes) {
2643 return resolveQualifiedMethod(pos, env, site.tsym, site, name, argtypes, typeargtypes);
2644 }
2645 Symbol resolveQualifiedMethod(DiagnosticPosition pos, Env<AttrContext> env,
2646 Symbol location, Type site, Name name, List<Type> argtypes,
2647 List<Type> typeargtypes) {
2648 return resolveQualifiedMethod(new MethodResolutionContext(), pos, env, location, site, name, argtypes, typeargtypes);
2649 }
2650 private Symbol resolveQualifiedMethod(MethodResolutionContext resolveContext,
2651 DiagnosticPosition pos, Env<AttrContext> env,
2652 Symbol location, Type site, Name name, List<Type> argtypes,
2653 List<Type> typeargtypes) {
2654 return lookupMethod(env, pos, location, resolveContext, new BasicLookupHelper(name, site, argtypes, typeargtypes) {
2655 @Override
2656 Symbol doLookup(Env<AttrContext> env, MethodResolutionPhase phase) {
2657 return findMethod(env, site, name, argtypes, typeargtypes,
2658 phase.isBoxingRequired(),
2659 phase.isVarargsRequired());
2660 }
2661 @Override
2662 Symbol access(Env<AttrContext> env, DiagnosticPosition pos, Symbol location, Symbol sym) {
2663 if (sym.kind.isResolutionError()) {
2664 sym = super.access(env, pos, location, sym);
2665 } else if (allowMethodHandles) {
2666 MethodSymbol msym = (MethodSymbol)sym;
2667 if ((msym.flags() & SIGNATURE_POLYMORPHIC) != 0) {
2668 return findPolymorphicSignatureInstance(env, sym, argtypes);
2669 }
2670 }
2671 return sym;
2672 }
2673 });
2674 }
2675
2676 /** Find or create an implicit method of exactly the given type (after erasure).
2677 * Searches in a side table, not the main scope of the site.
2678 * This emulates the lookup process required by JSR 292 in JVM.
2679 * @param env Attribution environment
2680 * @param spMethod signature polymorphic method - i.e. MH.invokeExact
2681 * @param argtypes The required argument types
2682 */
2683 Symbol findPolymorphicSignatureInstance(Env<AttrContext> env,
2684 final Symbol spMethod,
2685 List<Type> argtypes) {
2686 Type mtype = infer.instantiatePolymorphicSignatureInstance(env,
2687 (MethodSymbol)spMethod, currentResolutionContext, argtypes);
2688 for (Symbol sym : polymorphicSignatureScope.getSymbolsByName(spMethod.name)) {
2689 // Check that there is already a method symbol for the method
2690 // type and owner
2691 if (types.isSameType(mtype, sym.type) &&
2692 spMethod.owner == sym.owner) {
2693 return sym;
2694 }
2695 }
2696
2697 // Create the desired method
2698 // Retain static modifier is to support invocations to
2699 // MethodHandle.linkTo* methods
2700 long flags = ABSTRACT | HYPOTHETICAL |
2701 spMethod.flags() & (Flags.AccessFlags | Flags.STATIC);
2702 Symbol msym = new MethodSymbol(flags, spMethod.name, mtype, spMethod.owner) {
2703 @Override
2704 public Symbol baseSymbol() {
2705 return spMethod;
2706 }
2707 };
2708 if (!mtype.isErroneous()) { // Cache only if kosher.
2709 polymorphicSignatureScope.enter(msym);
2710 }
2711 return msym;
2712 }
2713
2714 /** Resolve a qualified method identifier, throw a fatal error if not
2715 * found.
2716 * @param pos The position to use for error reporting.
2717 * @param env The environment current at the method invocation.
2718 * @param site The type of the qualifying expression, in which
2719 * identifier is searched.
2720 * @param name The identifier's name.
2721 * @param argtypes The types of the invocation's value arguments.
2722 * @param typeargtypes The types of the invocation's type arguments.
2723 */
2724 public MethodSymbol resolveInternalMethod(DiagnosticPosition pos, Env<AttrContext> env,
2725 Type site, Name name,
2726 List<Type> argtypes,
2727 List<Type> typeargtypes) {
2728 MethodResolutionContext resolveContext = new MethodResolutionContext();
2729 resolveContext.internalResolution = true;
2730 Symbol sym = resolveQualifiedMethod(resolveContext, pos, env, site.tsym,
2731 site, name, argtypes, typeargtypes);
2732 if (sym.kind == MTH) return (MethodSymbol)sym;
2733 else throw new FatalError(
2734 diags.fragment(Fragments.FatalErrCantLocateMeth(name)));
2735 }
2736
2737 /** Resolve constructor.
2738 * @param pos The position to use for error reporting.
2739 * @param env The environment current at the constructor invocation.
2740 * @param site The type of class for which a constructor is searched.
2741 * @param argtypes The types of the constructor invocation's value
2742 * arguments.
2743 * @param typeargtypes The types of the constructor invocation's type
2744 * arguments.
2745 */
2746 Symbol resolveConstructor(DiagnosticPosition pos,
2747 Env<AttrContext> env,
2748 Type site,
2749 List<Type> argtypes,
2750 List<Type> typeargtypes) {
2751 return resolveConstructor(new MethodResolutionContext(), pos, env, site, argtypes, typeargtypes);
2752 }
2753
2754 private Symbol resolveConstructor(MethodResolutionContext resolveContext,
2755 final DiagnosticPosition pos,
2756 Env<AttrContext> env,
2757 Type site,
2758 List<Type> argtypes,
2759 List<Type> typeargtypes) {
2760 return lookupMethod(env, pos, site.tsym, resolveContext, new BasicLookupHelper(names.init, site, argtypes, typeargtypes) {
2761 @Override
2762 Symbol doLookup(Env<AttrContext> env, MethodResolutionPhase phase) {
2763 return findConstructor(pos, env, site, argtypes, typeargtypes,
2764 phase.isBoxingRequired(),
2765 phase.isVarargsRequired());
2766 }
2767 });
2768 }
2769
2770 /** Resolve a constructor, throw a fatal error if not found.
2771 * @param pos The position to use for error reporting.
2772 * @param env The environment current at the method invocation.
2773 * @param site The type to be constructed.
2774 * @param argtypes The types of the invocation's value arguments.
2775 * @param typeargtypes The types of the invocation's type arguments.
2776 */
2777 public MethodSymbol resolveInternalConstructor(DiagnosticPosition pos, Env<AttrContext> env,
2778 Type site,
2779 List<Type> argtypes,
2780 List<Type> typeargtypes) {
2781 MethodResolutionContext resolveContext = new MethodResolutionContext();
2782 resolveContext.internalResolution = true;
2783 Symbol sym = resolveConstructor(resolveContext, pos, env, site, argtypes, typeargtypes);
2784 if (sym.kind == MTH) return (MethodSymbol)sym;
2785 else throw new FatalError(
2786 diags.fragment(Fragments.FatalErrCantLocateCtor(site)));
2787 }
2788
2789 Symbol findConstructor(DiagnosticPosition pos, Env<AttrContext> env,
2790 Type site, List<Type> argtypes,
2791 List<Type> typeargtypes,
2792 boolean allowBoxing,
2793 boolean useVarargs) {
2794 Symbol sym = findMethod(env, site,
2795 names.init, argtypes,
2796 typeargtypes, allowBoxing,
2797 useVarargs);
2798 chk.checkDeprecated(pos, env.info.scope.owner, sym);
2799 return sym;
2800 }
2801
2802 /** Resolve constructor using diamond inference.
2803 * @param pos The position to use for error reporting.
2804 * @param env The environment current at the constructor invocation.
2805 * @param site The type of class for which a constructor is searched.
2806 * The scope of this class has been touched in attribution.
2807 * @param argtypes The types of the constructor invocation's value
2808 * arguments.
2809 * @param typeargtypes The types of the constructor invocation's type
2810 * arguments.
2811 */
2812 Symbol resolveDiamond(DiagnosticPosition pos,
2813 Env<AttrContext> env,
2814 Type site,
2815 List<Type> argtypes,
2816 List<Type> typeargtypes) {
2817 return lookupMethod(env, pos, site.tsym, resolveMethodCheck,
2818 new BasicLookupHelper(names.init, site, argtypes, typeargtypes) {
2819 @Override
2820 Symbol doLookup(Env<AttrContext> env, MethodResolutionPhase phase) {
2821 return findDiamond(env, site, argtypes, typeargtypes,
2822 phase.isBoxingRequired(),
2823 phase.isVarargsRequired());
2824 }
2825 @Override
2826 Symbol access(Env<AttrContext> env, DiagnosticPosition pos, Symbol location, Symbol sym) {
2827 if (sym.kind.isResolutionError()) {
2828 if (sym.kind != WRONG_MTH &&
2829 sym.kind != WRONG_MTHS) {
2830 sym = super.access(env, pos, location, sym);
2831 } else {
2832 final JCDiagnostic details = sym.kind == WRONG_MTH ?
2833 ((InapplicableSymbolError)sym.baseSymbol()).errCandidate().snd :
2834 null;
2835 sym = new DiamondError(sym, currentResolutionContext);
2836 sym = accessMethod(sym, pos, site, names.init, true, argtypes, typeargtypes);
2837 env.info.pendingResolutionPhase = currentResolutionContext.step;
2838 }
2839 }
2840 return sym;
2841 }});
2842 }
2843
2844 /** This method scans all the constructor symbol in a given class scope -
2845 * assuming that the original scope contains a constructor of the kind:
2846 * {@code Foo(X x, Y y)}, where X,Y are class type-variables declared in Foo,
2847 * a method check is executed against the modified constructor type:
2848 * {@code <X,Y>Foo<X,Y>(X x, Y y)}. This is crucial in order to enable diamond
2849 * inference. The inferred return type of the synthetic constructor IS
2850 * the inferred type for the diamond operator.
2851 */
2852 private Symbol findDiamond(Env<AttrContext> env,
2853 Type site,
2854 List<Type> argtypes,
2855 List<Type> typeargtypes,
2856 boolean allowBoxing,
2857 boolean useVarargs) {
2858 Symbol bestSoFar = methodNotFound;
2859 TypeSymbol tsym = site.tsym.isInterface() ? syms.objectType.tsym : site.tsym;
2860 for (final Symbol sym : tsym.members().getSymbolsByName(names.init)) {
2861 //- System.out.println(" e " + e.sym);
2862 if (sym.kind == MTH &&
2863 (sym.flags_field & SYNTHETIC) == 0) {
2864 List<Type> oldParams = sym.type.hasTag(FORALL) ?
2865 ((ForAll)sym.type).tvars :
2866 List.nil();
2867 Type constrType = new ForAll(site.tsym.type.getTypeArguments().appendList(oldParams),
2868 types.createMethodTypeWithReturn(sym.type.asMethodType(), site));
2869 MethodSymbol newConstr = new MethodSymbol(sym.flags(), names.init, constrType, site.tsym) {
2870 @Override
2871 public Symbol baseSymbol() {
2872 return sym;
2873 }
2874 };
2875 bestSoFar = selectBest(env, site, argtypes, typeargtypes,
2876 newConstr,
2877 bestSoFar,
2878 allowBoxing,
2879 useVarargs);
2880 }
2881 }
2882 return bestSoFar;
2883 }
2884
2885 Symbol getMemberReference(DiagnosticPosition pos,
2886 Env<AttrContext> env,
2887 JCMemberReference referenceTree,
2888 Type site,
2889 Name name) {
2890
2891 site = types.capture(site);
2892
2893 ReferenceLookupHelper lookupHelper = makeReferenceLookupHelper(
2894 referenceTree, site, name, List.nil(), null, VARARITY);
2895
2896 Env<AttrContext> newEnv = env.dup(env.tree, env.info.dup());
2897 Symbol sym = lookupMethod(newEnv, env.tree.pos(), site.tsym,
2898 nilMethodCheck, lookupHelper);
2899
2900 env.info.pendingResolutionPhase = newEnv.info.pendingResolutionPhase;
2901
2902 return sym;
2903 }
2904
2905 ReferenceLookupHelper makeReferenceLookupHelper(JCMemberReference referenceTree,
2906 Type site,
2907 Name name,
2908 List<Type> argtypes,
2909 List<Type> typeargtypes,
2910 MethodResolutionPhase maxPhase) {
2911 if (!name.equals(names.init)) {
2912 //method reference
2913 return new MethodReferenceLookupHelper(referenceTree, name, site, argtypes, typeargtypes, maxPhase);
2914 } else if (site.hasTag(ARRAY)) {
2915 //array constructor reference
2916 return new ArrayConstructorReferenceLookupHelper(referenceTree, site, argtypes, typeargtypes, maxPhase);
2917 } else {
2918 //class constructor reference
2919 return new ConstructorReferenceLookupHelper(referenceTree, site, argtypes, typeargtypes, maxPhase);
2920 }
2921 }
2922
2923 /**
2924 * Resolution of member references is typically done as a single
2925 * overload resolution step, where the argument types A are inferred from
2926 * the target functional descriptor.
2927 *
2928 * If the member reference is a method reference with a type qualifier,
2929 * a two-step lookup process is performed. The first step uses the
2930 * expected argument list A, while the second step discards the first
2931 * type from A (which is treated as a receiver type).
2932 *
2933 * There are two cases in which inference is performed: (i) if the member
2934 * reference is a constructor reference and the qualifier type is raw - in
2935 * which case diamond inference is used to infer a parameterization for the
2936 * type qualifier; (ii) if the member reference is an unbound reference
2937 * where the type qualifier is raw - in that case, during the unbound lookup
2938 * the receiver argument type is used to infer an instantiation for the raw
2939 * qualifier type.
2940 *
2941 * When a multi-step resolution process is exploited, the process of picking
2942 * the resulting symbol is delegated to an helper class {@link com.sun.tools.javac.comp.Resolve.ReferenceChooser}.
2943 *
2944 * This routine returns a pair (T,S), where S is the member reference symbol,
2945 * and T is the type of the class in which S is defined. This is necessary as
2946 * the type T might be dynamically inferred (i.e. if constructor reference
2947 * has a raw qualifier).
2948 */
2949 Pair<Symbol, ReferenceLookupHelper> resolveMemberReference(Env<AttrContext> env,
2950 JCMemberReference referenceTree,
2951 Type site,
2952 Name name,
2953 List<Type> argtypes,
2954 List<Type> typeargtypes,
2955 MethodCheck methodCheck,
2956 InferenceContext inferenceContext,
2957 ReferenceChooser referenceChooser) {
2958
2959 //step 1 - bound lookup
2960 ReferenceLookupHelper boundLookupHelper = makeReferenceLookupHelper(
2961 referenceTree, site, name, argtypes, typeargtypes, VARARITY);
2962 Env<AttrContext> boundEnv = env.dup(env.tree, env.info.dup());
2963 MethodResolutionContext boundSearchResolveContext = new MethodResolutionContext();
2964 boundSearchResolveContext.methodCheck = methodCheck;
2965 Symbol boundSym = lookupMethod(boundEnv, env.tree.pos(),
2966 site.tsym, boundSearchResolveContext, boundLookupHelper);
2967 ReferenceLookupResult boundRes = new ReferenceLookupResult(boundSym, boundSearchResolveContext);
2968
2969 //step 2 - unbound lookup
2970 Symbol unboundSym = methodNotFound;
2971 Env<AttrContext> unboundEnv = env.dup(env.tree, env.info.dup());
2972 ReferenceLookupHelper unboundLookupHelper = boundLookupHelper.unboundLookup(inferenceContext);
2973 ReferenceLookupResult unboundRes = referenceNotFound;
2974 if (unboundLookupHelper != null) {
2975 MethodResolutionContext unboundSearchResolveContext =
2976 new MethodResolutionContext();
2977 unboundSearchResolveContext.methodCheck = methodCheck;
2978 unboundSym = lookupMethod(unboundEnv, env.tree.pos(),
2979 site.tsym, unboundSearchResolveContext, unboundLookupHelper);
2980 unboundRes = new ReferenceLookupResult(unboundSym, unboundSearchResolveContext);
2981 }
2982
2983 //merge results
2984 Pair<Symbol, ReferenceLookupHelper> res;
2985 ReferenceLookupResult bestRes = referenceChooser.result(boundRes, unboundRes);
2986 res = new Pair<>(bestRes.sym,
2987 bestRes == unboundRes ? unboundLookupHelper : boundLookupHelper);
2988 env.info.pendingResolutionPhase = bestRes == unboundRes ?
2989 unboundEnv.info.pendingResolutionPhase :
2990 boundEnv.info.pendingResolutionPhase;
2991
2992 return res;
2993 }
2994
2995 /**
2996 * This class is used to represent a method reference lookup result. It keeps track of two
2997 * things: (i) the symbol found during a method reference lookup and (ii) the static kind
2998 * of the lookup (see {@link com.sun.tools.javac.comp.Resolve.ReferenceLookupResult.StaticKind}).
2999 */
3000 static class ReferenceLookupResult {
3001
3002 /**
3003 * Static kind associated with a method reference lookup. Erroneous lookups end up with
3004 * the UNDEFINED kind; successful lookups will end up with either STATIC, NON_STATIC,
3005 * depending on whether all applicable candidates are static or non-static methods,
3006 * respectively. If a successful lookup has both static and non-static applicable methods,
3007 * its kind is set to BOTH.
3008 */
3009 enum StaticKind {
3010 STATIC,
3011 NON_STATIC,
3012 BOTH,
3013 UNDEFINED;
3014
3015 /**
3016 * Retrieve the static kind associated with a given (method) symbol.
3017 */
3018 static StaticKind from(Symbol s) {
3019 return s.isStatic() ?
3020 STATIC : NON_STATIC;
3021 }
3022
3023 /**
3024 * Merge two static kinds together.
3025 */
3026 static StaticKind reduce(StaticKind sk1, StaticKind sk2) {
3027 if (sk1 == UNDEFINED) {
3028 return sk2;
3029 } else if (sk2 == UNDEFINED) {
3030 return sk1;
3031 } else {
3032 return sk1 == sk2 ? sk1 : BOTH;
3033 }
3034 }
3035 }
3036
3037 /** The static kind. */
3038 StaticKind staticKind;
3039
3040 /** The lookup result. */
3041 Symbol sym;
3042
3043 ReferenceLookupResult(Symbol sym, MethodResolutionContext resolutionContext) {
3044 this(sym, staticKind(sym, resolutionContext));
3045 }
3046
3047 private ReferenceLookupResult(Symbol sym, StaticKind staticKind) {
3048 this.staticKind = staticKind;
3049 this.sym = sym;
3050 }
3051
3052 private static StaticKind staticKind(Symbol sym, MethodResolutionContext resolutionContext) {
3053 switch (sym.kind) {
3054 case MTH:
3055 case AMBIGUOUS:
3056 return resolutionContext.candidates.stream()
3057 .filter(c -> c.isApplicable() && c.step == resolutionContext.step)
3058 .map(c -> StaticKind.from(c.sym))
3059 .reduce(StaticKind::reduce)
3060 .orElse(StaticKind.UNDEFINED);
3061 default:
3062 return StaticKind.UNDEFINED;
3063 }
3064 }
3065
3066 /**
3067 * Does this result corresponds to a successful lookup (i.e. one where a method has been found?)
3068 */
3069 boolean isSuccess() {
3070 return staticKind != StaticKind.UNDEFINED;
3071 }
3072
3073 /**
3074 * Does this result have given static kind?
3075 */
3076 boolean hasKind(StaticKind sk) {
3077 return this.staticKind == sk;
3078 }
3079
3080 /**
3081 * Error recovery helper: can this lookup result be ignored (for the purpose of returning
3082 * some 'better' result) ?
3083 */
3084 boolean canIgnore() {
3085 switch (sym.kind) {
3086 case ABSENT_MTH:
3087 return true;
3088 case WRONG_MTH:
3089 InapplicableSymbolError errSym =
3090 (InapplicableSymbolError)sym.baseSymbol();
3091 return new Template(MethodCheckDiag.ARITY_MISMATCH.regex())
3092 .matches(errSym.errCandidate().snd);
3093 case WRONG_MTHS:
3094 InapplicableSymbolsError errSyms =
3095 (InapplicableSymbolsError)sym.baseSymbol();
3096 return errSyms.filterCandidates(errSyms.mapCandidates()).isEmpty();
3097 default:
3098 return false;
3099 }
3100 }
3101
3102 static ReferenceLookupResult error(Symbol sym) {
3103 return new ReferenceLookupResult(sym, StaticKind.UNDEFINED);
3104 }
3105 }
3106
3107 /**
3108 * This abstract class embodies the logic that converts one (bound lookup) or two (unbound lookup)
3109 * {@code ReferenceLookupResult} objects into a (@code Symbol), which is then regarded as the
3110 * result of method reference resolution.
3111 */
3112 abstract class ReferenceChooser {
3113 /**
3114 * Generate a result from a pair of lookup result objects. This method delegates to the
3115 * appropriate result generation routine.
3116 */
3117 ReferenceLookupResult result(ReferenceLookupResult boundRes, ReferenceLookupResult unboundRes) {
3118 return unboundRes != referenceNotFound ?
3119 unboundResult(boundRes, unboundRes) :
3120 boundResult(boundRes);
3121 }
3122
3123 /**
3124 * Generate a symbol from a given bound lookup result.
3125 */
3126 abstract ReferenceLookupResult boundResult(ReferenceLookupResult boundRes);
3127
3128 /**
3129 * Generate a symbol from a pair of bound/unbound lookup results.
3130 */
3131 abstract ReferenceLookupResult unboundResult(ReferenceLookupResult boundRes, ReferenceLookupResult unboundRes);
3132 }
3133
3134 /**
3135 * This chooser implements the selection strategy used during a full lookup; this logic
3136 * is described in JLS SE 8 (15.3.2).
3137 */
3138 ReferenceChooser basicReferenceChooser = new ReferenceChooser() {
3139
3140 @Override
3141 ReferenceLookupResult boundResult(ReferenceLookupResult boundRes) {
3142 return !boundRes.isSuccess() || boundRes.hasKind(StaticKind.NON_STATIC) ?
3143 boundRes : //the search produces a non-static method
3144 ReferenceLookupResult.error(new BadMethodReferenceError(boundRes.sym, false));
3145 }
3146
3147 @Override
3148 ReferenceLookupResult unboundResult(ReferenceLookupResult boundRes, ReferenceLookupResult unboundRes) {
3149 if (boundRes.hasKind(StaticKind.STATIC) &&
3150 (!unboundRes.isSuccess() || unboundRes.hasKind(StaticKind.STATIC))) {
3151 //the first search produces a static method and no non-static method is applicable
3152 //during the second search
3153 return boundRes;
3154 } else if (unboundRes.hasKind(StaticKind.NON_STATIC) &&
3155 (!boundRes.isSuccess() || boundRes.hasKind(StaticKind.NON_STATIC))) {
3156 //the second search produces a non-static method and no static method is applicable
3157 //during the first search
3158 return unboundRes;
3159 } else if (boundRes.isSuccess() && unboundRes.isSuccess()) {
3160 //both searches produce some result; ambiguity (error recovery)
3161 return ReferenceLookupResult.error(ambiguityError(boundRes.sym, unboundRes.sym));
3162 } else if (boundRes.isSuccess() || unboundRes.isSuccess()) {
3163 //Both searches failed to produce a result with correct staticness (i.e. first search
3164 //produces an non-static method). Alternatively, a given search produced a result
3165 //with the right staticness, but the other search has applicable methods with wrong
3166 //staticness (error recovery)
3167 return ReferenceLookupResult.error(new BadMethodReferenceError(boundRes.isSuccess() ?
3168 boundRes.sym : unboundRes.sym, true));
3169 } else {
3170 //both searches fail to produce a result - pick 'better' error using heuristics (error recovery)
3171 return (boundRes.canIgnore() && !unboundRes.canIgnore()) ?
3172 unboundRes : boundRes;
3173 }
3174 }
3175 };
3176
3177 /**
3178 * This chooser implements the selection strategy used during an arity-based lookup; this logic
3179 * is described in JLS SE 8 (15.12.2.1).
3180 */
3181 ReferenceChooser structuralReferenceChooser = new ReferenceChooser() {
3182
3183 @Override
3184 ReferenceLookupResult boundResult(ReferenceLookupResult boundRes) {
3185 return (!boundRes.isSuccess() || !boundRes.hasKind(StaticKind.STATIC)) ?
3186 boundRes : //the search has at least one applicable non-static method
3187 ReferenceLookupResult.error(new BadMethodReferenceError(boundRes.sym, false));
3188 }
3189
3190 @Override
3191 ReferenceLookupResult unboundResult(ReferenceLookupResult boundRes, ReferenceLookupResult unboundRes) {
3192 if (boundRes.isSuccess() && !boundRes.hasKind(StaticKind.NON_STATIC)) {
3193 //the first serach has at least one applicable static method
3194 return boundRes;
3195 } else if (unboundRes.isSuccess() && !unboundRes.hasKind(StaticKind.STATIC)) {
3196 //the second search has at least one applicable non-static method
3197 return unboundRes;
3198 } else if (boundRes.isSuccess() || unboundRes.isSuccess()) {
3199 //either the first search produces a non-static method, or second search produces
3200 //a non-static method (error recovery)
3201 return ReferenceLookupResult.error(new BadMethodReferenceError(boundRes.isSuccess() ?
3202 boundRes.sym : unboundRes.sym, true));
3203 } else {
3204 //both searches fail to produce a result - pick 'better' error using heuristics (error recovery)
3205 return (boundRes.canIgnore() && !unboundRes.canIgnore()) ?
3206 unboundRes : boundRes;
3207 }
3208 }
3209 };
3210
3211 /**
3212 * Helper for defining custom method-like lookup logic; a lookup helper
3213 * provides hooks for (i) the actual lookup logic and (ii) accessing the
3214 * lookup result (this step might result in compiler diagnostics to be generated)
3215 */
3216 abstract class LookupHelper {
3217
3218 /** name of the symbol to lookup */
3219 Name name;
3220
3221 /** location in which the lookup takes place */
3222 Type site;
3223
3224 /** actual types used during the lookup */
3225 List<Type> argtypes;
3226
3227 /** type arguments used during the lookup */
3228 List<Type> typeargtypes;
3229
3230 /** Max overload resolution phase handled by this helper */
3231 MethodResolutionPhase maxPhase;
3232
3233 LookupHelper(Name name, Type site, List<Type> argtypes, List<Type> typeargtypes, MethodResolutionPhase maxPhase) {
3234 this.name = name;
3235 this.site = site;
3236 this.argtypes = argtypes;
3237 this.typeargtypes = typeargtypes;
3238 this.maxPhase = maxPhase;
3239 }
3240
3241 /**
3242 * Should lookup stop at given phase with given result
3243 */
3244 final boolean shouldStop(Symbol sym, MethodResolutionPhase phase) {
3245 return phase.ordinal() > maxPhase.ordinal() ||
3246 !sym.kind.isResolutionError() || sym.kind == AMBIGUOUS;
3247 }
3248
3249 /**
3250 * Search for a symbol under a given overload resolution phase - this method
3251 * is usually called several times, once per each overload resolution phase
3252 */
3253 abstract Symbol lookup(Env<AttrContext> env, MethodResolutionPhase phase);
3254
3255 /**
3256 * Dump overload resolution info
3257 */
3258 void debug(DiagnosticPosition pos, Symbol sym) {
3259 //do nothing
3260 }
3261
3262 /**
3263 * Validate the result of the lookup
3264 */
3265 abstract Symbol access(Env<AttrContext> env, DiagnosticPosition pos, Symbol location, Symbol sym);
3266 }
3267
3268 abstract class BasicLookupHelper extends LookupHelper {
3269
3270 BasicLookupHelper(Name name, Type site, List<Type> argtypes, List<Type> typeargtypes) {
3271 this(name, site, argtypes, typeargtypes, MethodResolutionPhase.VARARITY);
3272 }
3273
3274 BasicLookupHelper(Name name, Type site, List<Type> argtypes, List<Type> typeargtypes, MethodResolutionPhase maxPhase) {
3275 super(name, site, argtypes, typeargtypes, maxPhase);
3276 }
3277
3278 @Override
3279 final Symbol lookup(Env<AttrContext> env, MethodResolutionPhase phase) {
3280 Symbol sym = doLookup(env, phase);
3281 if (sym.kind == AMBIGUOUS) {
3282 AmbiguityError a_err = (AmbiguityError)sym.baseSymbol();
3283 sym = a_err.mergeAbstracts(site);
3284 }
3285 return sym;
3286 }
3287
3288 abstract Symbol doLookup(Env<AttrContext> env, MethodResolutionPhase phase);
3289
3290 @Override
3291 Symbol access(Env<AttrContext> env, DiagnosticPosition pos, Symbol location, Symbol sym) {
3292 if (sym.kind.isResolutionError()) {
3293 //if nothing is found return the 'first' error
3294 sym = accessMethod(sym, pos, location, site, name, true, argtypes, typeargtypes);
3295 }
3296 return sym;
3297 }
3298
3299 @Override
3300 void debug(DiagnosticPosition pos, Symbol sym) {
3301 reportVerboseResolutionDiagnostic(pos, name, site, argtypes, typeargtypes, sym);
3302 }
3303 }
3304
3305 /**
3306 * Helper class for member reference lookup. A reference lookup helper
3307 * defines the basic logic for member reference lookup; a method gives
3308 * access to an 'unbound' helper used to perform an unbound member
3309 * reference lookup.
3310 */
3311 abstract class ReferenceLookupHelper extends LookupHelper {
3312
3313 /** The member reference tree */
3314 JCMemberReference referenceTree;
3315
3316 ReferenceLookupHelper(JCMemberReference referenceTree, Name name, Type site,
3317 List<Type> argtypes, List<Type> typeargtypes, MethodResolutionPhase maxPhase) {
3318 super(name, site, argtypes, typeargtypes, maxPhase);
3319 this.referenceTree = referenceTree;
3320 }
3321
3322 /**
3323 * Returns an unbound version of this lookup helper. By default, this
3324 * method returns an dummy lookup helper.
3325 */
3326 ReferenceLookupHelper unboundLookup(InferenceContext inferenceContext) {
3327 return null;
3328 }
3329
3330 /**
3331 * Get the kind of the member reference
3332 */
3333 abstract JCMemberReference.ReferenceKind referenceKind(Symbol sym);
3334
3335 Symbol access(Env<AttrContext> env, DiagnosticPosition pos, Symbol location, Symbol sym) {
3336 if (sym.kind == AMBIGUOUS) {
3337 AmbiguityError a_err = (AmbiguityError)sym.baseSymbol();
3338 sym = a_err.mergeAbstracts(site);
3339 }
3340 //skip error reporting
3341 return sym;
3342 }
3343 }
3344
3345 /**
3346 * Helper class for method reference lookup. The lookup logic is based
3347 * upon Resolve.findMethod; in certain cases, this helper class has a
3348 * corresponding unbound helper class (see UnboundMethodReferenceLookupHelper).
3349 * In such cases, non-static lookup results are thrown away.
3350 */
3351 class MethodReferenceLookupHelper extends ReferenceLookupHelper {
3352
3353 /** The original method reference lookup site. */
3354 Type originalSite;
3355
3356 MethodReferenceLookupHelper(JCMemberReference referenceTree, Name name, Type site,
3357 List<Type> argtypes, List<Type> typeargtypes, MethodResolutionPhase maxPhase) {
3358 super(referenceTree, name, types.skipTypeVars(site, true), argtypes, typeargtypes, maxPhase);
3359 this.originalSite = site;
3360 }
3361
3362 @Override
3363 final Symbol lookup(Env<AttrContext> env, MethodResolutionPhase phase) {
3364 return findMethod(env, site, name, argtypes, typeargtypes,
3365 phase.isBoxingRequired(), phase.isVarargsRequired());
3366 }
3367
3368 @Override
3369 ReferenceLookupHelper unboundLookup(InferenceContext inferenceContext) {
3370 if (TreeInfo.isStaticSelector(referenceTree.expr, names)) {
3371 if (argtypes.nonEmpty() &&
3372 (argtypes.head.hasTag(NONE) ||
3373 types.isSubtypeUnchecked(inferenceContext.asUndetVar(argtypes.head), originalSite))) {
3374 return new UnboundMethodReferenceLookupHelper(referenceTree, name,
3375 originalSite, argtypes, typeargtypes, maxPhase);
3376 } else {
3377 return new ReferenceLookupHelper(referenceTree, name, site, argtypes, typeargtypes, maxPhase) {
3378 @Override
3379 ReferenceLookupHelper unboundLookup(InferenceContext inferenceContext) {
3380 return this;
3381 }
3382
3383 @Override
3384 Symbol lookup(Env<AttrContext> env, MethodResolutionPhase phase) {
3385 return methodNotFound;
3386 }
3387
3388 @Override
3389 ReferenceKind referenceKind(Symbol sym) {
3390 Assert.error();
3391 return null;
3392 }
3393 };
3394 }
3395 } else {
3396 return super.unboundLookup(inferenceContext);
3397 }
3398 }
3399
3400 @Override
3401 ReferenceKind referenceKind(Symbol sym) {
3402 if (sym.isStatic()) {
3403 return ReferenceKind.STATIC;
3404 } else {
3405 Name selName = TreeInfo.name(referenceTree.getQualifierExpression());
3406 return selName != null && selName == names._super ?
3407 ReferenceKind.SUPER :
3408 ReferenceKind.BOUND;
3409 }
3410 }
3411 }
3412
3413 /**
3414 * Helper class for unbound method reference lookup. Essentially the same
3415 * as the basic method reference lookup helper; main difference is that static
3416 * lookup results are thrown away. If qualifier type is raw, an attempt to
3417 * infer a parameterized type is made using the first actual argument (that
3418 * would otherwise be ignored during the lookup).
3419 */
3420 class UnboundMethodReferenceLookupHelper extends MethodReferenceLookupHelper {
3421
3422 UnboundMethodReferenceLookupHelper(JCMemberReference referenceTree, Name name, Type site,
3423 List<Type> argtypes, List<Type> typeargtypes, MethodResolutionPhase maxPhase) {
3424 super(referenceTree, name, site, argtypes.tail, typeargtypes, maxPhase);
3425 if (site.isRaw() && !argtypes.head.hasTag(NONE)) {
3426 Type asSuperSite = types.asSuper(argtypes.head, site.tsym);
3427 this.site = types.skipTypeVars(asSuperSite, true);
3428 }
3429 }
3430
3431 @Override
3432 ReferenceLookupHelper unboundLookup(InferenceContext inferenceContext) {
3433 return this;
3434 }
3435
3436 @Override
3437 ReferenceKind referenceKind(Symbol sym) {
3438 return ReferenceKind.UNBOUND;
3439 }
3440 }
3441
3442 /**
3443 * Helper class for array constructor lookup; an array constructor lookup
3444 * is simulated by looking up a method that returns the array type specified
3445 * as qualifier, and that accepts a single int parameter (size of the array).
3446 */
3447 class ArrayConstructorReferenceLookupHelper extends ReferenceLookupHelper {
3448
3449 ArrayConstructorReferenceLookupHelper(JCMemberReference referenceTree, Type site, List<Type> argtypes,
3450 List<Type> typeargtypes, MethodResolutionPhase maxPhase) {
3451 super(referenceTree, names.init, site, argtypes, typeargtypes, maxPhase);
3452 }
3453
3454 @Override
3455 protected Symbol lookup(Env<AttrContext> env, MethodResolutionPhase phase) {
3456 WriteableScope sc = WriteableScope.create(syms.arrayClass);
3457 MethodSymbol arrayConstr = new MethodSymbol(PUBLIC, name, null, site.tsym);
3458 arrayConstr.type = new MethodType(List.of(syms.intType), site, List.nil(), syms.methodClass);
3459 sc.enter(arrayConstr);
3460 return findMethodInScope(env, site, name, argtypes, typeargtypes, sc, methodNotFound, phase.isBoxingRequired(), phase.isVarargsRequired(), false);
3461 }
3462
3463 @Override
3464 ReferenceKind referenceKind(Symbol sym) {
3465 return ReferenceKind.ARRAY_CTOR;
3466 }
3467 }
3468
3469 /**
3470 * Helper class for constructor reference lookup. The lookup logic is based
3471 * upon either Resolve.findMethod or Resolve.findDiamond - depending on
3472 * whether the constructor reference needs diamond inference (this is the case
3473 * if the qualifier type is raw). A special erroneous symbol is returned
3474 * if the lookup returns the constructor of an inner class and there's no
3475 * enclosing instance in scope.
3476 */
3477 class ConstructorReferenceLookupHelper extends ReferenceLookupHelper {
3478
3479 boolean needsInference;
3480
3481 ConstructorReferenceLookupHelper(JCMemberReference referenceTree, Type site, List<Type> argtypes,
3482 List<Type> typeargtypes, MethodResolutionPhase maxPhase) {
3483 super(referenceTree, names.init, site, argtypes, typeargtypes, maxPhase);
3484 if (site.isRaw()) {
3485 this.site = new ClassType(site.getEnclosingType(), site.tsym.type.getTypeArguments(), site.tsym, site.getMetadata());
3486 needsInference = true;
3487 }
3488 }
3489
3490 @Override
3491 protected Symbol lookup(Env<AttrContext> env, MethodResolutionPhase phase) {
3492 Symbol sym = needsInference ?
3493 findDiamond(env, site, argtypes, typeargtypes, phase.isBoxingRequired(), phase.isVarargsRequired()) :
3494 findMethod(env, site, name, argtypes, typeargtypes,
3495 phase.isBoxingRequired(), phase.isVarargsRequired());
3496 return enclosingInstanceMissing(env, site) ? new BadConstructorReferenceError(sym) : sym;
3497 }
3498
3499 @Override
3500 ReferenceKind referenceKind(Symbol sym) {
3501 return site.getEnclosingType().hasTag(NONE) ?
3502 ReferenceKind.TOPLEVEL : ReferenceKind.IMPLICIT_INNER;
3503 }
3504 }
3505
3506 /**
3507 * Main overload resolution routine. On each overload resolution step, a
3508 * lookup helper class is used to perform the method/constructor lookup;
3509 * at the end of the lookup, the helper is used to validate the results
3510 * (this last step might trigger overload resolution diagnostics).
3511 */
3512 Symbol lookupMethod(Env<AttrContext> env, DiagnosticPosition pos, Symbol location, MethodCheck methodCheck, LookupHelper lookupHelper) {
3513 MethodResolutionContext resolveContext = new MethodResolutionContext();
3514 resolveContext.methodCheck = methodCheck;
3515 return lookupMethod(env, pos, location, resolveContext, lookupHelper);
3516 }
3517
3518 Symbol lookupMethod(Env<AttrContext> env, DiagnosticPosition pos, Symbol location,
3519 MethodResolutionContext resolveContext, LookupHelper lookupHelper) {
3520 MethodResolutionContext prevResolutionContext = currentResolutionContext;
3521 try {
3522 Symbol bestSoFar = methodNotFound;
3523 currentResolutionContext = resolveContext;
3524 for (MethodResolutionPhase phase : methodResolutionSteps) {
3525 if (lookupHelper.shouldStop(bestSoFar, phase))
3526 break;
3527 MethodResolutionPhase prevPhase = currentResolutionContext.step;
3528 Symbol prevBest = bestSoFar;
3529 currentResolutionContext.step = phase;
3530 Symbol sym = lookupHelper.lookup(env, phase);
3531 lookupHelper.debug(pos, sym);
3532 bestSoFar = phase.mergeResults(bestSoFar, sym);
3533 env.info.pendingResolutionPhase = (prevBest == bestSoFar) ? prevPhase : phase;
3534 }
3535 return lookupHelper.access(env, pos, location, bestSoFar);
3536 } finally {
3537 currentResolutionContext = prevResolutionContext;
3538 }
3539 }
3540
3541 /**
3542 * Resolve `c.name' where name == this or name == super.
3543 * @param pos The position to use for error reporting.
3544 * @param env The environment current at the expression.
3545 * @param c The qualifier.
3546 * @param name The identifier's name.
3547 */
3548 Symbol resolveSelf(DiagnosticPosition pos,
3549 Env<AttrContext> env,
3550 TypeSymbol c,
3551 Name name) {
3552 Env<AttrContext> env1 = env;
3553 boolean staticOnly = false;
3554 while (env1.outer != null) {
3555 if (isStatic(env1)) staticOnly = true;
3556 if (env1.enclClass.sym == c) {
3557 Symbol sym = env1.info.scope.findFirst(name);
3558 if (sym != null) {
3559 if (staticOnly) sym = new StaticError(sym);
3560 return accessBase(sym, pos, env.enclClass.sym.type,
3561 name, true);
3562 }
3563 }
3564 if ((env1.enclClass.sym.flags() & STATIC) != 0) staticOnly = true;
3565 env1 = env1.outer;
3566 }
3567 if (c.isInterface() &&
3568 name == names._super && !isStatic(env) &&
3569 types.isDirectSuperInterface(c, env.enclClass.sym)) {
3570 //this might be a default super call if one of the superinterfaces is 'c'
3571 for (Type t : pruneInterfaces(env.enclClass.type)) {
3572 if (t.tsym == c) {
3573 env.info.defaultSuperCallSite = t;
3574 return new VarSymbol(0, names._super,
3575 types.asSuper(env.enclClass.type, c), env.enclClass.sym);
3576 }
3577 }
3578 //find a direct super type that is a subtype of 'c'
3579 for (Type i : types.directSupertypes(env.enclClass.type)) {
3580 if (i.tsym.isSubClass(c, types) && i.tsym != c) {
3581 log.error(pos,
3582 Errors.IllegalDefaultSuperCall(c,
3583 Fragments.RedundantSupertype(c, i)));
3584 return syms.errSymbol;
3585 }
3586 }
3587 Assert.error();
3588 }
3589 log.error(pos, Errors.NotEnclClass(c));
3590 return syms.errSymbol;
3591 }
3592 //where
3593 private List<Type> pruneInterfaces(Type t) {
3594 ListBuffer<Type> result = new ListBuffer<>();
3595 for (Type t1 : types.interfaces(t)) {
3596 boolean shouldAdd = true;
3597 for (Type t2 : types.directSupertypes(t)) {
3598 if (t1 != t2 && types.isSubtypeNoCapture(t2, t1)) {
3599 shouldAdd = false;
3600 }
3601 }
3602 if (shouldAdd) {
3603 result.append(t1);
3604 }
3605 }
3606 return result.toList();
3607 }
3608
3609
3610 /**
3611 * Resolve `c.this' for an enclosing class c that contains the
3612 * named member.
3613 * @param pos The position to use for error reporting.
3614 * @param env The environment current at the expression.
3615 * @param member The member that must be contained in the result.
3616 */
3617 Symbol resolveSelfContaining(DiagnosticPosition pos,
3618 Env<AttrContext> env,
3619 Symbol member,
3620 boolean isSuperCall) {
3621 Symbol sym = resolveSelfContainingInternal(env, member, isSuperCall);
3622 if (sym == null) {
3623 log.error(pos, Errors.EnclClassRequired(member));
3624 return syms.errSymbol;
3625 } else {
3626 return accessBase(sym, pos, env.enclClass.sym.type, sym.name, true);
3627 }
3628 }
3629
3630 boolean enclosingInstanceMissing(Env<AttrContext> env, Type type) {
3631 if (type.hasTag(CLASS) && type.getEnclosingType().hasTag(CLASS)) {
3632 Symbol encl = resolveSelfContainingInternal(env, type.tsym, false);
3633 return encl == null || encl.kind.isResolutionError();
3634 }
3635 return false;
3636 }
3637
3638 private Symbol resolveSelfContainingInternal(Env<AttrContext> env,
3639 Symbol member,
3640 boolean isSuperCall) {
3641 Name name = names._this;
3642 Env<AttrContext> env1 = isSuperCall ? env.outer : env;
3643 boolean staticOnly = false;
3644 if (env1 != null) {
3645 while (env1 != null && env1.outer != null) {
3646 if (isStatic(env1)) staticOnly = true;
3647 if (env1.enclClass.sym.isSubClass(member.owner.enclClass(), types)) {
3648 Symbol sym = env1.info.scope.findFirst(name);
3649 if (sym != null) {
3650 if (staticOnly) sym = new StaticError(sym);
3651 return sym;
3652 }
3653 }
3654 if ((env1.enclClass.sym.flags() & STATIC) != 0)
3655 staticOnly = true;
3656 env1 = env1.outer;
3657 }
3658 }
3659 return null;
3660 }
3661
3662 /**
3663 * Resolve an appropriate implicit this instance for t's container.
3664 * JLS 8.8.5.1 and 15.9.2
3665 */
3666 Type resolveImplicitThis(DiagnosticPosition pos, Env<AttrContext> env, Type t) {
3667 return resolveImplicitThis(pos, env, t, false);
3668 }
3669
3670 Type resolveImplicitThis(DiagnosticPosition pos, Env<AttrContext> env, Type t, boolean isSuperCall) {
3671 Type thisType = (t.tsym.owner.kind.matches(KindSelector.VAL_MTH)
3672 ? resolveSelf(pos, env, t.getEnclosingType().tsym, names._this)
3673 : resolveSelfContaining(pos, env, t.tsym, isSuperCall)).type;
3674 if (env.info.isSelfCall && thisType.tsym == env.enclClass.sym) {
3675 log.error(pos, Errors.CantRefBeforeCtorCalled("this"));
3676 }
3677 return thisType;
3678 }
3679
3680 /* ***************************************************************************
3681 * ResolveError classes, indicating error situations when accessing symbols
3682 ****************************************************************************/
3683
3684 //used by TransTypes when checking target type of synthetic cast
3685 public void logAccessErrorInternal(Env<AttrContext> env, JCTree tree, Type type) {
3686 AccessError error = new AccessError(env, env.enclClass.type, type.tsym);
3687 logResolveError(error, tree.pos(), env.enclClass.sym, env.enclClass.type, null, null, null);
3688 }
3689 //where
3690 private void logResolveError(ResolveError error,
3691 DiagnosticPosition pos,
3692 Symbol location,
3693 Type site,
3694 Name name,
3695 List<Type> argtypes,
3696 List<Type> typeargtypes) {
3697 JCDiagnostic d = error.getDiagnostic(JCDiagnostic.DiagnosticType.ERROR,
3698 pos, location, site, name, argtypes, typeargtypes);
3699 if (d != null) {
3700 d.setFlag(DiagnosticFlag.RESOLVE_ERROR);
3701 log.report(d);
3702 }
3703 }
3704
3705 private final LocalizedString noArgs = new LocalizedString("compiler.misc.no.args");
3706
3707 public Object methodArguments(List<Type> argtypes) {
3708 if (argtypes == null || argtypes.isEmpty()) {
3709 return noArgs;
3710 } else {
3711 ListBuffer<Object> diagArgs = new ListBuffer<>();
3712 for (Type t : argtypes) {
3713 if (t.hasTag(DEFERRED)) {
3714 diagArgs.append(((DeferredAttr.DeferredType)t).tree);
3715 } else {
3716 diagArgs.append(t);
3717 }
3718 }
3719 return diagArgs;
3720 }
3721 }
3722
3723 /**
3724 * Root class for resolution errors. Subclass of ResolveError
3725 * represent a different kinds of resolution error - as such they must
3726 * specify how they map into concrete compiler diagnostics.
3727 */
3728 abstract class ResolveError extends Symbol {
3729
3730 /** The name of the kind of error, for debugging only. */
3731 final String debugName;
3732
3733 ResolveError(Kind kind, String debugName) {
3734 super(kind, 0, null, null, null);
3735 this.debugName = debugName;
3736 }
3737
3738 @Override @DefinedBy(Api.LANGUAGE_MODEL)
3739 public <R, P> R accept(ElementVisitor<R, P> v, P p) {
3740 throw new AssertionError();
3741 }
3742
3743 @Override
3744 public String toString() {
3745 return debugName;
3746 }
3747
3748 @Override
3749 public boolean exists() {
3750 return false;
3751 }
3752
3753 @Override
3754 public boolean isStatic() {
3755 return false;
3756 }
3757
3758 /**
3759 * Create an external representation for this erroneous symbol to be
3760 * used during attribution - by default this returns the symbol of a
3761 * brand new error type which stores the original type found
3762 * during resolution.
3763 *
3764 * @param name the name used during resolution
3765 * @param location the location from which the symbol is accessed
3766 */
3767 protected Symbol access(Name name, TypeSymbol location) {
3768 return types.createErrorType(name, location, syms.errSymbol.type).tsym;
3769 }
3770
3771 /**
3772 * Create a diagnostic representing this resolution error.
3773 *
3774 * @param dkind The kind of the diagnostic to be created (e.g error).
3775 * @param pos The position to be used for error reporting.
3776 * @param site The original type from where the selection took place.
3777 * @param name The name of the symbol to be resolved.
3778 * @param argtypes The invocation's value arguments,
3779 * if we looked for a method.
3780 * @param typeargtypes The invocation's type arguments,
3781 * if we looked for a method.
3782 */
3783 abstract JCDiagnostic getDiagnostic(JCDiagnostic.DiagnosticType dkind,
3784 DiagnosticPosition pos,
3785 Symbol location,
3786 Type site,
3787 Name name,
3788 List<Type> argtypes,
3789 List<Type> typeargtypes);
3790 }
3791
3792 /**
3793 * This class is the root class of all resolution errors caused by
3794 * an invalid symbol being found during resolution.
3795 */
3796 abstract class InvalidSymbolError extends ResolveError {
3797
3798 /** The invalid symbol found during resolution */
3799 Symbol sym;
3800
3801 InvalidSymbolError(Kind kind, Symbol sym, String debugName) {
3802 super(kind, debugName);
3803 this.sym = sym;
3804 }
3805
3806 @Override
3807 public boolean exists() {
3808 return true;
3809 }
3810
3811 @Override
3812 public String toString() {
3813 return super.toString() + " wrongSym=" + sym;
3814 }
3815
3816 @Override
3817 public Symbol access(Name name, TypeSymbol location) {
3818 if (!sym.kind.isResolutionError() && sym.kind.matches(KindSelector.TYP))
3819 return types.createErrorType(name, location, sym.type).tsym;
3820 else
3821 return sym;
3822 }
3823 }
3824
3825 class BadVarTypeError extends ResolveError {
3826 BadVarTypeError() {
3827 super(Kind.BAD_VAR, "bad var use");
3828 }
3829
3830 @Override
3831 JCDiagnostic getDiagnostic(DiagnosticType dkind, DiagnosticPosition pos, Symbol location, Type site, Name name, List<Type> argtypes, List<Type> typeargtypes) {
3832 return diags.create(dkind, log.currentSource(), pos, "illegal.ref.to.var.type", name);
3833 }
3834 }
3835
3836 /**
3837 * InvalidSymbolError error class indicating that a symbol matching a
3838 * given name does not exists in a given site.
3839 */
3840 class SymbolNotFoundError extends ResolveError {
3841
3842 SymbolNotFoundError(Kind kind) {
3843 this(kind, "symbol not found error");
3844 }
3845
3846 SymbolNotFoundError(Kind kind, String debugName) {
3847 super(kind, debugName);
3848 }
3849
3850 @Override
3851 JCDiagnostic getDiagnostic(JCDiagnostic.DiagnosticType dkind,
3852 DiagnosticPosition pos,
3853 Symbol location,
3854 Type site,
3855 Name name,
3856 List<Type> argtypes,
3857 List<Type> typeargtypes) {
3858 argtypes = argtypes == null ? List.nil() : argtypes;
3859 typeargtypes = typeargtypes == null ? List.nil() : typeargtypes;
3860 if (name == names.error)
3861 return null;
3862
3863 boolean hasLocation = false;
3864 if (location == null) {
3865 location = site.tsym;
3866 }
3867 if (!location.name.isEmpty()) {
3868 if (location.kind == PCK && !site.tsym.exists()) {
3869 return diags.create(dkind, log.currentSource(), pos,
3870 "doesnt.exist", location);
3871 }
3872 hasLocation = !location.name.equals(names._this) &&
3873 !location.name.equals(names._super);
3874 }
3875 boolean isConstructor = name == names.init;
3876 KindName kindname = isConstructor ? KindName.CONSTRUCTOR : kind.absentKind();
3877 Name idname = isConstructor ? site.tsym.name : name;
3878 String errKey = getErrorKey(kindname, typeargtypes.nonEmpty(), hasLocation);
3879 if (hasLocation) {
3880 return diags.create(dkind, log.currentSource(), pos,
3881 errKey, kindname, idname, //symbol kindname, name
3882 typeargtypes, args(argtypes), //type parameters and arguments (if any)
3883 getLocationDiag(location, site)); //location kindname, type
3884 }
3885 else {
3886 return diags.create(dkind, log.currentSource(), pos,
3887 errKey, kindname, idname, //symbol kindname, name
3888 typeargtypes, args(argtypes)); //type parameters and arguments (if any)
3889 }
3890 }
3891 //where
3892 private Object args(List<Type> args) {
3893 return args.isEmpty() ? args : methodArguments(args);
3894 }
3895
3896 private String getErrorKey(KindName kindname, boolean hasTypeArgs, boolean hasLocation) {
3897 String key = "cant.resolve";
3898 String suffix = hasLocation ? ".location" : "";
3899 switch (kindname) {
3900 case METHOD:
3901 case CONSTRUCTOR: {
3902 suffix += ".args";
3903 suffix += hasTypeArgs ? ".params" : "";
3904 }
3905 }
3906 return key + suffix;
3907 }
3908 private JCDiagnostic getLocationDiag(Symbol location, Type site) {
3909 if (location.kind == VAR) {
3910 return diags.fragment(Fragments.Location1(kindName(location),
3911 location,
3912 location.type));
3913 } else {
3914 return diags.fragment(Fragments.Location(typeKindName(site),
3915 site,
3916 null));
3917 }
3918 }
3919 }
3920
3921 /**
3922 * InvalidSymbolError error class indicating that a given symbol
3923 * (either a method, a constructor or an operand) is not applicable
3924 * given an actual arguments/type argument list.
3925 */
3926 class InapplicableSymbolError extends ResolveError {
3927
3928 protected MethodResolutionContext resolveContext;
3929
3930 InapplicableSymbolError(MethodResolutionContext context) {
3931 this(WRONG_MTH, "inapplicable symbol error", context);
3932 }
3933
3934 protected InapplicableSymbolError(Kind kind, String debugName, MethodResolutionContext context) {
3935 super(kind, debugName);
3936 this.resolveContext = context;
3937 }
3938
3939 @Override
3940 public String toString() {
3941 return super.toString();
3942 }
3943
3944 @Override
3945 public boolean exists() {
3946 return true;
3947 }
3948
3949 @Override
3950 JCDiagnostic getDiagnostic(JCDiagnostic.DiagnosticType dkind,
3951 DiagnosticPosition pos,
3952 Symbol location,
3953 Type site,
3954 Name name,
3955 List<Type> argtypes,
3956 List<Type> typeargtypes) {
3957 if (name == names.error)
3958 return null;
3959
3960 Pair<Symbol, JCDiagnostic> c = errCandidate();
3961 if (compactMethodDiags) {
3962 JCDiagnostic simpleDiag =
3963 MethodResolutionDiagHelper.rewrite(diags, pos, log.currentSource(), dkind, c.snd);
3964 if (simpleDiag != null) {
3965 return simpleDiag;
3966 }
3967 }
3968 Symbol ws = c.fst.asMemberOf(site, types);
3969 return diags.create(dkind, log.currentSource(), pos,
3970 "cant.apply.symbol",
3971 kindName(ws),
3972 ws.name == names.init ? ws.owner.name : ws.name,
3973 methodArguments(ws.type.getParameterTypes()),
3974 methodArguments(argtypes),
3975 kindName(ws.owner),
3976 ws.owner.type,
3977 c.snd);
3978 }
3979
3980 @Override
3981 public Symbol access(Name name, TypeSymbol location) {
3982 return types.createErrorType(name, location, syms.errSymbol.type).tsym;
3983 }
3984
3985 protected Pair<Symbol, JCDiagnostic> errCandidate() {
3986 Candidate bestSoFar = null;
3987 for (Candidate c : resolveContext.candidates) {
3988 if (c.isApplicable()) continue;
3989 bestSoFar = c;
3990 }
3991 Assert.checkNonNull(bestSoFar);
3992 return new Pair<>(bestSoFar.sym, bestSoFar.details);
3993 }
3994 }
3995
3996 /**
3997 * ResolveError error class indicating that a symbol (either methods, constructors or operand)
3998 * is not applicable given an actual arguments/type argument list.
3999 */
4000 class InapplicableSymbolsError extends InapplicableSymbolError {
4001
4002 InapplicableSymbolsError(MethodResolutionContext context) {
4003 super(WRONG_MTHS, "inapplicable symbols", context);
4004 }
4005
4006 @Override
4007 JCDiagnostic getDiagnostic(JCDiagnostic.DiagnosticType dkind,
4008 DiagnosticPosition pos,
4009 Symbol location,
4010 Type site,
4011 Name name,
4012 List<Type> argtypes,
4013 List<Type> typeargtypes) {
4014 Map<Symbol, JCDiagnostic> candidatesMap = mapCandidates();
4015 Map<Symbol, JCDiagnostic> filteredCandidates = compactMethodDiags ?
4016 filterCandidates(candidatesMap) :
4017 mapCandidates();
4018 if (filteredCandidates.isEmpty()) {
4019 filteredCandidates = candidatesMap;
4020 }
4021 boolean truncatedDiag = candidatesMap.size() != filteredCandidates.size();
4022 if (filteredCandidates.size() > 1) {
4023 JCDiagnostic err = diags.create(dkind,
4024 null,
4025 truncatedDiag ?
4026 EnumSet.of(DiagnosticFlag.COMPRESSED) :
4027 EnumSet.noneOf(DiagnosticFlag.class),
4028 log.currentSource(),
4029 pos,
4030 "cant.apply.symbols",
4031 name == names.init ? KindName.CONSTRUCTOR : kind.absentKind(),
4032 name == names.init ? site.tsym.name : name,
4033 methodArguments(argtypes));
4034 return new JCDiagnostic.MultilineDiagnostic(err, candidateDetails(filteredCandidates, site));
4035 } else if (filteredCandidates.size() == 1) {
4036 Map.Entry<Symbol, JCDiagnostic> _e =
4037 filteredCandidates.entrySet().iterator().next();
4038 final Pair<Symbol, JCDiagnostic> p = new Pair<>(_e.getKey(), _e.getValue());
4039 JCDiagnostic d = new InapplicableSymbolError(resolveContext) {
4040 @Override
4041 protected Pair<Symbol, JCDiagnostic> errCandidate() {
4042 return p;
4043 }
4044 }.getDiagnostic(dkind, pos,
4045 location, site, name, argtypes, typeargtypes);
4046 if (truncatedDiag) {
4047 d.setFlag(DiagnosticFlag.COMPRESSED);
4048 }
4049 return d;
4050 } else {
4051 return new SymbolNotFoundError(ABSENT_MTH).getDiagnostic(dkind, pos,
4052 location, site, name, argtypes, typeargtypes);
4053 }
4054 }
4055 //where
4056 private Map<Symbol, JCDiagnostic> mapCandidates() {
4057 MostSpecificMap candidates = new MostSpecificMap();
4058 for (Candidate c : resolveContext.candidates) {
4059 if (c.isApplicable()) continue;
4060 candidates.put(c);
4061 }
4062 return candidates;
4063 }
4064
4065 @SuppressWarnings("serial")
4066 private class MostSpecificMap extends LinkedHashMap<Symbol, JCDiagnostic> {
4067 private void put(Candidate c) {
4068 ListBuffer<Symbol> overridden = new ListBuffer<>();
4069 for (Symbol s : keySet()) {
4070 if (s == c.sym) {
4071 continue;
4072 }
4073 if (c.sym.overrides(s, (TypeSymbol)s.owner, types, false)) {
4074 overridden.add(s);
4075 } else if (s.overrides(c.sym, (TypeSymbol)c.sym.owner, types, false)) {
4076 return;
4077 }
4078 }
4079 for (Symbol s : overridden) {
4080 remove(s);
4081 }
4082 put(c.sym, c.details);
4083 }
4084 }
4085
4086 Map<Symbol, JCDiagnostic> filterCandidates(Map<Symbol, JCDiagnostic> candidatesMap) {
4087 Map<Symbol, JCDiagnostic> candidates = new LinkedHashMap<>();
4088 for (Map.Entry<Symbol, JCDiagnostic> _entry : candidatesMap.entrySet()) {
4089 JCDiagnostic d = _entry.getValue();
4090 if (!new Template(MethodCheckDiag.ARITY_MISMATCH.regex()).matches(d)) {
4091 candidates.put(_entry.getKey(), d);
4092 }
4093 }
4094 return candidates;
4095 }
4096
4097 private List<JCDiagnostic> candidateDetails(Map<Symbol, JCDiagnostic> candidatesMap, Type site) {
4098 List<JCDiagnostic> details = List.nil();
4099 for (Map.Entry<Symbol, JCDiagnostic> _entry : candidatesMap.entrySet()) {
4100 Symbol sym = _entry.getKey();
4101 JCDiagnostic detailDiag =
4102 diags.fragment(Fragments.InapplicableMethod(Kinds.kindName(sym),
4103 sym.location(site, types),
4104 sym.asMemberOf(site, types),
4105 _entry.getValue()));
4106 details = details.prepend(detailDiag);
4107 }
4108 //typically members are visited in reverse order (see Scope)
4109 //so we need to reverse the candidate list so that candidates
4110 //conform to source order
4111 return details;
4112 }
4113 }
4114
4115 /**
4116 * DiamondError error class indicating that a constructor symbol is not applicable
4117 * given an actual arguments/type argument list using diamond inference.
4118 */
4119 class DiamondError extends InapplicableSymbolError {
4120
4121 Symbol sym;
4122
4123 public DiamondError(Symbol sym, MethodResolutionContext context) {
4124 super(sym.kind, "diamondError", context);
4125 this.sym = sym;
4126 }
4127
4128 JCDiagnostic getDetails() {
4129 return (sym.kind == WRONG_MTH) ?
4130 ((InapplicableSymbolError)sym.baseSymbol()).errCandidate().snd :
4131 null;
4132 }
4133
4134 @Override
4135 JCDiagnostic getDiagnostic(DiagnosticType dkind, DiagnosticPosition pos,
4136 Symbol location, Type site, Name name, List<Type> argtypes, List<Type> typeargtypes) {
4137 JCDiagnostic details = getDetails();
4138 if (details != null && compactMethodDiags) {
4139 JCDiagnostic simpleDiag =
4140 MethodResolutionDiagHelper.rewrite(diags, pos, log.currentSource(), dkind, details);
4141 if (simpleDiag != null) {
4142 return simpleDiag;
4143 }
4144 }
4145 String key = details == null ?
4146 "cant.apply.diamond" :
4147 "cant.apply.diamond.1";
4148 return diags.create(dkind, log.currentSource(), pos, key,
4149 Fragments.Diamond(site.tsym), details);
4150 }
4151 }
4152
4153 /**
4154 * An InvalidSymbolError error class indicating that a symbol is not
4155 * accessible from a given site
4156 */
4157 class AccessError extends InvalidSymbolError {
4158
4159 private Env<AttrContext> env;
4160 private Type site;
4161
4162 AccessError(Env<AttrContext> env, Type site, Symbol sym) {
4163 super(HIDDEN, sym, "access error");
4164 this.env = env;
4165 this.site = site;
4166 }
4167
4168 @Override
4169 public boolean exists() {
4170 return false;
4171 }
4172
4173 @Override
4174 JCDiagnostic getDiagnostic(JCDiagnostic.DiagnosticType dkind,
4175 DiagnosticPosition pos,
4176 Symbol location,
4177 Type site,
4178 Name name,
4179 List<Type> argtypes,
4180 List<Type> typeargtypes) {
4181 if (sym.owner.type.hasTag(ERROR))
4182 return null;
4183
4184 if (sym.name == names.init && sym.owner != site.tsym) {
4185 return new SymbolNotFoundError(ABSENT_MTH).getDiagnostic(dkind,
4186 pos, location, site, name, argtypes, typeargtypes);
4187 }
4188 else if ((sym.flags() & PUBLIC) != 0
4189 || (env != null && this.site != null
4190 && !isAccessible(env, this.site))) {
4191 if (sym.owner.kind == PCK) {
4192 return diags.create(dkind, log.currentSource(),
4193 pos, "not.def.access.package.cant.access",
4194 sym, sym.location(), inaccessiblePackageReason(env, sym.packge()));
4195 } else if ( sym.packge() != syms.rootPackage
4196 && !symbolPackageVisible(env, sym)) {
4197 return diags.create(dkind, log.currentSource(),
4198 pos, "not.def.access.class.intf.cant.access.reason",
4199 sym, sym.location(), sym.location().packge(),
4200 inaccessiblePackageReason(env, sym.packge()));
4201 } else {
4202 return diags.create(dkind, log.currentSource(),
4203 pos, "not.def.access.class.intf.cant.access",
4204 sym, sym.location());
4205 }
4206 }
4207 else if ((sym.flags() & (PRIVATE | PROTECTED)) != 0) {
4208 return diags.create(dkind, log.currentSource(),
4209 pos, "report.access", sym,
4210 asFlagSet(sym.flags() & (PRIVATE | PROTECTED)),
4211 sym.location());
4212 }
4213 else {
4214 return diags.create(dkind, log.currentSource(),
4215 pos, "not.def.public.cant.access", sym, sym.location());
4216 }
4217 }
4218
4219 private String toString(Type type) {
4220 StringBuilder sb = new StringBuilder();
4221 sb.append(type);
4222 if (type != null) {
4223 sb.append("[tsym:").append(type.tsym);
4224 if (type.tsym != null)
4225 sb.append("packge:").append(type.tsym.packge());
4226 sb.append("]");
4227 }
4228 return sb.toString();
4229 }
4230 }
4231
4232 class InvisibleSymbolError extends InvalidSymbolError {
4233
4234 private final Env<AttrContext> env;
4235 private final boolean suppressError;
4236
4237 InvisibleSymbolError(Env<AttrContext> env, boolean suppressError, Symbol sym) {
4238 super(HIDDEN, sym, "invisible class error");
4239 this.env = env;
4240 this.suppressError = suppressError;
4241 this.name = sym.name;
4242 }
4243
4244 @Override
4245 JCDiagnostic getDiagnostic(JCDiagnostic.DiagnosticType dkind,
4246 DiagnosticPosition pos,
4247 Symbol location,
4248 Type site,
4249 Name name,
4250 List<Type> argtypes,
4251 List<Type> typeargtypes) {
4252 if (suppressError)
4253 return null;
4254
4255 if (sym.kind == PCK) {
4256 JCDiagnostic details = inaccessiblePackageReason(env, sym.packge());
4257 return diags.create(dkind, log.currentSource(),
4258 pos, "package.not.visible", sym, details);
4259 }
4260
4261 JCDiagnostic details = inaccessiblePackageReason(env, sym.packge());
4262
4263 if (pos.getTree() != null) {
4264 Symbol o = sym;
4265 JCTree tree = pos.getTree();
4266
4267 while (o.kind != PCK && tree.hasTag(SELECT)) {
4268 o = o.owner;
4269 tree = ((JCFieldAccess) tree).selected;
4270 }
4271
4272 if (o.kind == PCK) {
4273 pos = tree.pos();
4274
4275 return diags.create(dkind, log.currentSource(),
4276 pos, "package.not.visible", o, details);
4277 }
4278 }
4279
4280 return diags.create(dkind, log.currentSource(),
4281 pos, "not.def.access.package.cant.access", sym, sym.packge(), details);
4282 }
4283 }
4284
4285 JCDiagnostic inaccessiblePackageReason(Env<AttrContext> env, PackageSymbol sym) {
4286 //no dependency:
4287 if (!env.toplevel.modle.readModules.contains(sym.modle)) {
4288 //does not read:
4289 if (sym.modle != syms.unnamedModule) {
4290 if (env.toplevel.modle != syms.unnamedModule) {
4291 return diags.fragment(Fragments.NotDefAccessDoesNotRead(env.toplevel.modle,
4292 sym,
4293 sym.modle));
4294 } else {
4295 return diags.fragment(Fragments.NotDefAccessDoesNotReadFromUnnamed(sym,
4296 sym.modle));
4297 }
4298 } else {
4299 return diags.fragment(Fragments.NotDefAccessDoesNotReadUnnamed(sym,
4300 env.toplevel.modle));
4301 }
4302 } else {
4303 if (sym.packge().modle.exports.stream().anyMatch(e -> e.packge == sym)) {
4304 //not exported to this module:
4305 if (env.toplevel.modle != syms.unnamedModule) {
4306 return diags.fragment(Fragments.NotDefAccessNotExportedToModule(sym,
4307 sym.modle,
4308 env.toplevel.modle));
4309 } else {
4310 return diags.fragment(Fragments.NotDefAccessNotExportedToModuleFromUnnamed(sym,
4311 sym.modle));
4312 }
4313 } else {
4314 //not exported:
4315 if (env.toplevel.modle != syms.unnamedModule) {
4316 return diags.fragment(Fragments.NotDefAccessNotExported(sym,
4317 sym.modle));
4318 } else {
4319 return diags.fragment(Fragments.NotDefAccessNotExportedFromUnnamed(sym,
4320 sym.modle));
4321 }
4322 }
4323 }
4324 }
4325
4326 /**
4327 * InvalidSymbolError error class indicating that an instance member
4328 * has erroneously been accessed from a static context.
4329 */
4330 class StaticError extends InvalidSymbolError {
4331
4332 StaticError(Symbol sym) {
4333 super(STATICERR, sym, "static error");
4334 }
4335
4336 @Override
4337 JCDiagnostic getDiagnostic(JCDiagnostic.DiagnosticType dkind,
4338 DiagnosticPosition pos,
4339 Symbol location,
4340 Type site,
4341 Name name,
4342 List<Type> argtypes,
4343 List<Type> typeargtypes) {
4344 Symbol errSym = ((sym.kind == TYP && sym.type.hasTag(CLASS))
4345 ? types.erasure(sym.type).tsym
4346 : sym);
4347 return diags.create(dkind, log.currentSource(), pos,
4348 "non-static.cant.be.ref", kindName(sym), errSym);
4349 }
4350 }
4351
4352 /**
4353 * InvalidSymbolError error class indicating that a pair of symbols
4354 * (either methods, constructors or operands) are ambiguous
4355 * given an actual arguments/type argument list.
4356 */
4357 class AmbiguityError extends ResolveError {
4358
4359 /** The other maximally specific symbol */
4360 List<Symbol> ambiguousSyms = List.nil();
4361
4362 @Override
4363 public boolean exists() {
4364 return true;
4365 }
4366
4367 AmbiguityError(Symbol sym1, Symbol sym2) {
4368 super(AMBIGUOUS, "ambiguity error");
4369 ambiguousSyms = flatten(sym2).appendList(flatten(sym1));
4370 }
4371
4372 private List<Symbol> flatten(Symbol sym) {
4373 if (sym.kind == AMBIGUOUS) {
4374 return ((AmbiguityError)sym.baseSymbol()).ambiguousSyms;
4375 } else {
4376 return List.of(sym);
4377 }
4378 }
4379
4380 AmbiguityError addAmbiguousSymbol(Symbol s) {
4381 ambiguousSyms = ambiguousSyms.prepend(s);
4382 return this;
4383 }
4384
4385 @Override
4386 JCDiagnostic getDiagnostic(JCDiagnostic.DiagnosticType dkind,
4387 DiagnosticPosition pos,
4388 Symbol location,
4389 Type site,
4390 Name name,
4391 List<Type> argtypes,
4392 List<Type> typeargtypes) {
4393 List<Symbol> diagSyms = ambiguousSyms.reverse();
4394 Symbol s1 = diagSyms.head;
4395 Symbol s2 = diagSyms.tail.head;
4396 Name sname = s1.name;
4397 if (sname == names.init) sname = s1.owner.name;
4398 return diags.create(dkind, log.currentSource(),
4399 pos, "ref.ambiguous", sname,
4400 kindName(s1),
4401 s1,
4402 s1.location(site, types),
4403 kindName(s2),
4404 s2,
4405 s2.location(site, types));
4406 }
4407
4408 /**
4409 * If multiple applicable methods are found during overload and none of them
4410 * is more specific than the others, attempt to merge their signatures.
4411 */
4412 Symbol mergeAbstracts(Type site) {
4413 List<Symbol> ambiguousInOrder = ambiguousSyms.reverse();
4414 return types.mergeAbstracts(ambiguousInOrder, site, true).orElse(this);
4415 }
4416
4417 @Override
4418 protected Symbol access(Name name, TypeSymbol location) {
4419 Symbol firstAmbiguity = ambiguousSyms.last();
4420 return firstAmbiguity.kind == TYP ?
4421 types.createErrorType(name, location, firstAmbiguity.type).tsym :
4422 firstAmbiguity;
4423 }
4424 }
4425
4426 class BadVarargsMethod extends ResolveError {
4427
4428 ResolveError delegatedError;
4429
4430 BadVarargsMethod(ResolveError delegatedError) {
4431 super(delegatedError.kind, "badVarargs");
4432 this.delegatedError = delegatedError;
4433 }
4434
4435 @Override
4436 public Symbol baseSymbol() {
4437 return delegatedError.baseSymbol();
4438 }
4439
4440 @Override
4441 protected Symbol access(Name name, TypeSymbol location) {
4442 return delegatedError.access(name, location);
4443 }
4444
4445 @Override
4446 public boolean exists() {
4447 return true;
4448 }
4449
4450 @Override
4451 JCDiagnostic getDiagnostic(DiagnosticType dkind, DiagnosticPosition pos, Symbol location, Type site, Name name, List<Type> argtypes, List<Type> typeargtypes) {
4452 return delegatedError.getDiagnostic(dkind, pos, location, site, name, argtypes, typeargtypes);
4453 }
4454 }
4455
4456 /**
4457 * BadMethodReferenceError error class indicating that a method reference symbol has been found,
4458 * but with the wrong staticness.
4459 */
4460 class BadMethodReferenceError extends StaticError {
4461
4462 boolean unboundLookup;
4463
4464 public BadMethodReferenceError(Symbol sym, boolean unboundLookup) {
4465 super(sym);
4466 this.unboundLookup = unboundLookup;
4467 }
4468
4469 @Override
4470 JCDiagnostic getDiagnostic(DiagnosticType dkind, DiagnosticPosition pos, Symbol location, Type site, Name name, List<Type> argtypes, List<Type> typeargtypes) {
4471 final String key;
4472 if (!unboundLookup) {
4473 key = "bad.static.method.in.bound.lookup";
4474 } else if (sym.isStatic()) {
4475 key = "bad.static.method.in.unbound.lookup";
4476 } else {
4477 key = "bad.instance.method.in.unbound.lookup";
4478 }
4479 return sym.kind.isResolutionError() ?
4480 ((ResolveError)sym).getDiagnostic(dkind, pos, location, site, name, argtypes, typeargtypes) :
4481 diags.create(dkind, log.currentSource(), pos, key, Kinds.kindName(sym), sym);
4482 }
4483 }
4484
4485 /**
4486 * BadConstructorReferenceError error class indicating that a constructor reference symbol has been found,
4487 * but pointing to a class for which an enclosing instance is not available.
4488 */
4489 class BadConstructorReferenceError extends InvalidSymbolError {
4490
4491 public BadConstructorReferenceError(Symbol sym) {
4492 super(MISSING_ENCL, sym, "BadConstructorReferenceError");
4493 }
4494
4495 @Override
4496 JCDiagnostic getDiagnostic(DiagnosticType dkind, DiagnosticPosition pos, Symbol location, Type site, Name name, List<Type> argtypes, List<Type> typeargtypes) {
4497 return diags.create(dkind, log.currentSource(), pos,
4498 "cant.access.inner.cls.constr", site.tsym.name, argtypes, site.getEnclosingType());
4499 }
4500 }
4501
4502 /**
4503 * Helper class for method resolution diagnostic simplification.
4504 * Certain resolution diagnostic are rewritten as simpler diagnostic
4505 * where the enclosing resolution diagnostic (i.e. 'inapplicable method')
4506 * is stripped away, as it doesn't carry additional info. The logic
4507 * for matching a given diagnostic is given in terms of a template
4508 * hierarchy: a diagnostic template can be specified programmatically,
4509 * so that only certain diagnostics are matched. Each templete is then
4510 * associated with a rewriter object that carries out the task of rewtiting
4511 * the diagnostic to a simpler one.
4512 */
4513 static class MethodResolutionDiagHelper {
4514
4515 /**
4516 * A diagnostic rewriter transforms a method resolution diagnostic
4517 * into a simpler one
4518 */
4519 interface DiagnosticRewriter {
4520 JCDiagnostic rewriteDiagnostic(JCDiagnostic.Factory diags,
4521 DiagnosticPosition preferedPos, DiagnosticSource preferredSource,
4522 DiagnosticType preferredKind, JCDiagnostic d);
4523 }
4524
4525 /**
4526 * A diagnostic template is made up of two ingredients: (i) a regular
4527 * expression for matching a diagnostic key and (ii) a list of sub-templates
4528 * for matching diagnostic arguments.
4529 */
4530 static class Template {
4531
4532 /** regex used to match diag key */
4533 String regex;
4534
4535 /** templates used to match diagnostic args */
4536 Template[] subTemplates;
4537
4538 Template(String key, Template... subTemplates) {
4539 this.regex = key;
4540 this.subTemplates = subTemplates;
4541 }
4542
4543 /**
4544 * Returns true if the regex matches the diagnostic key and if
4545 * all diagnostic arguments are matches by corresponding sub-templates.
4546 */
4547 boolean matches(Object o) {
4548 JCDiagnostic d = (JCDiagnostic)o;
4549 Object[] args = d.getArgs();
4550 if (!d.getCode().matches(regex) ||
4551 subTemplates.length != d.getArgs().length) {
4552 return false;
4553 }
4554 for (int i = 0; i < args.length ; i++) {
4555 if (!subTemplates[i].matches(args[i])) {
4556 return false;
4557 }
4558 }
4559 return true;
4560 }
4561 }
4562
4563 /**
4564 * Common rewriter for all argument mismatch simplifications.
4565 */
4566 static class ArgMismatchRewriter implements DiagnosticRewriter {
4567
4568 /** the index of the subdiagnostic to be used as primary. */
4569 int causeIndex;
4570
4571 public ArgMismatchRewriter(int causeIndex) {
4572 this.causeIndex = causeIndex;
4573 }
4574
4575 @Override
4576 public JCDiagnostic rewriteDiagnostic(JCDiagnostic.Factory diags,
4577 DiagnosticPosition preferedPos, DiagnosticSource preferredSource,
4578 DiagnosticType preferredKind, JCDiagnostic d) {
4579 JCDiagnostic cause = (JCDiagnostic)d.getArgs()[causeIndex];
4580 DiagnosticPosition pos = d.getDiagnosticPosition();
4581 if (pos == null) {
4582 pos = preferedPos;
4583 }
4584 return diags.create(preferredKind, preferredSource, pos,
4585 "prob.found.req", cause);
4586 }
4587 }
4588
4589 /** a dummy template that match any diagnostic argument */
4590 static final Template skip = new Template("") {
4591 @Override
4592 boolean matches(Object d) {
4593 return true;
4594 }
4595 };
4596
4597 /** template for matching inference-free arguments mismatch failures */
4598 static final Template argMismatchTemplate = new Template(MethodCheckDiag.ARG_MISMATCH.regex(), skip);
4599
4600 /** template for matching inference related arguments mismatch failures */
4601 static final Template inferArgMismatchTemplate = new Template(MethodCheckDiag.ARG_MISMATCH.regex(), skip, skip) {
4602 @Override
4603 boolean matches(Object o) {
4604 if (!super.matches(o)) {
4605 return false;
4606 }
4607 JCDiagnostic d = (JCDiagnostic)o;
4608 @SuppressWarnings("unchecked")
4609 List<Type> tvars = (List<Type>)d.getArgs()[0];
4610 return !containsAny(d, tvars);
4611 }
4612
4613 BiPredicate<Object, List<Type>> containsPredicate = (o, ts) -> {
4614 if (o instanceof Type) {
4615 return ((Type)o).containsAny(ts);
4616 } else if (o instanceof JCDiagnostic) {
4617 return containsAny((JCDiagnostic)o, ts);
4618 } else {
4619 return false;
4620 }
4621 };
4622
4623 boolean containsAny(JCDiagnostic d, List<Type> ts) {
4624 return Stream.of(d.getArgs())
4625 .anyMatch(o -> containsPredicate.test(o, ts));
4626 }
4627 };
4628
4629 /** rewriter map used for method resolution simplification */
4630 static final Map<Template, DiagnosticRewriter> rewriters = new LinkedHashMap<>();
4631
4632 static {
4633 rewriters.put(argMismatchTemplate, new ArgMismatchRewriter(0));
4634 rewriters.put(inferArgMismatchTemplate, new ArgMismatchRewriter(1));
4635 }
4636
4637 /**
4638 * Main entry point for diagnostic rewriting - given a diagnostic, see if any templates matches it,
4639 * and rewrite it accordingly.
4640 */
4641 static JCDiagnostic rewrite(JCDiagnostic.Factory diags, DiagnosticPosition pos, DiagnosticSource source,
4642 DiagnosticType dkind, JCDiagnostic d) {
4643 for (Map.Entry<Template, DiagnosticRewriter> _entry : rewriters.entrySet()) {
4644 if (_entry.getKey().matches(d)) {
4645 JCDiagnostic simpleDiag =
4646 _entry.getValue().rewriteDiagnostic(diags, pos, source, dkind, d);
4647 simpleDiag.setFlag(DiagnosticFlag.COMPRESSED);
4648 return simpleDiag;
4649 }
4650 }
4651 return null;
4652 }
4653 }
4654
4655 enum MethodResolutionPhase {
4656 BASIC(false, false),
4657 BOX(true, false),
4658 VARARITY(true, true) {
4659 @Override
4660 public Symbol mergeResults(Symbol bestSoFar, Symbol sym) {
4661 //Check invariants (see {@code LookupHelper.shouldStop})
4662 Assert.check(bestSoFar.kind.isResolutionError() && bestSoFar.kind != AMBIGUOUS);
4663 if (!sym.kind.isResolutionError()) {
4664 //varargs resolution successful
4665 return sym;
4666 } else {
4667 //pick best error
4668 switch (bestSoFar.kind) {
4669 case WRONG_MTH:
4670 case WRONG_MTHS:
4671 //Override previous errors if they were caused by argument mismatch.
4672 //This generally means preferring current symbols - but we need to pay
4673 //attention to the fact that the varargs lookup returns 'less' candidates
4674 //than the previous rounds, and adjust that accordingly.
4675 switch (sym.kind) {
4676 case WRONG_MTH:
4677 //if the previous round matched more than one method, return that
4678 //result instead
4679 return bestSoFar.kind == WRONG_MTHS ?
4680 bestSoFar : sym;
4681 case ABSENT_MTH:
4682 //do not override erroneous symbol if the arity lookup did not
4683 //match any method
4684 return bestSoFar;
4685 case WRONG_MTHS:
4686 default:
4687 //safe to override
4688 return sym;
4689 }
4690 default:
4691 //otherwise, return first error
4692 return bestSoFar;
4693 }
4694 }
4695 }
4696 };
4697
4698 final boolean isBoxingRequired;
4699 final boolean isVarargsRequired;
4700
4701 MethodResolutionPhase(boolean isBoxingRequired, boolean isVarargsRequired) {
4702 this.isBoxingRequired = isBoxingRequired;
4703 this.isVarargsRequired = isVarargsRequired;
4704 }
4705
4706 public boolean isBoxingRequired() {
4707 return isBoxingRequired;
4708 }
4709
4710 public boolean isVarargsRequired() {
4711 return isVarargsRequired;
4712 }
4713
4714 public Symbol mergeResults(Symbol prev, Symbol sym) {
4715 return sym;
4716 }
4717 }
4718
4719 final List<MethodResolutionPhase> methodResolutionSteps = List.of(BASIC, BOX, VARARITY);
4720
4721 /**
4722 * A resolution context is used to keep track of intermediate results of
4723 * overload resolution, such as list of method that are not applicable
4724 * (used to generate more precise diagnostics) and so on. Resolution contexts
4725 * can be nested - this means that when each overload resolution routine should
4726 * work within the resolution context it created.
4727 */
4728 class MethodResolutionContext {
4729
4730 private List<Candidate> candidates = List.nil();
4731
4732 MethodResolutionPhase step = null;
4733
4734 MethodCheck methodCheck = resolveMethodCheck;
4735
4736 private boolean internalResolution = false;
4737 private DeferredAttr.AttrMode attrMode = DeferredAttr.AttrMode.SPECULATIVE;
4738
4739 void addInapplicableCandidate(Symbol sym, JCDiagnostic details) {
4740 Candidate c = new Candidate(currentResolutionContext.step, sym, details, null);
4741 candidates = candidates.append(c);
4742 }
4743
4744 void addApplicableCandidate(Symbol sym, Type mtype) {
4745 Candidate c = new Candidate(currentResolutionContext.step, sym, null, mtype);
4746 candidates = candidates.append(c);
4747 }
4748
4749 DeferredAttrContext deferredAttrContext(Symbol sym, InferenceContext inferenceContext, ResultInfo pendingResult, Warner warn) {
4750 DeferredAttrContext parent = (pendingResult == null)
4751 ? deferredAttr.emptyDeferredAttrContext
4752 : pendingResult.checkContext.deferredAttrContext();
4753 return deferredAttr.new DeferredAttrContext(attrMode, sym, step,
4754 inferenceContext, parent, warn);
4755 }
4756
4757 /**
4758 * This class represents an overload resolution candidate. There are two
4759 * kinds of candidates: applicable methods and inapplicable methods;
4760 * applicable methods have a pointer to the instantiated method type,
4761 * while inapplicable candidates contain further details about the
4762 * reason why the method has been considered inapplicable.
4763 */
4764 @SuppressWarnings("overrides")
4765 class Candidate {
4766
4767 final MethodResolutionPhase step;
4768 final Symbol sym;
4769 final JCDiagnostic details;
4770 final Type mtype;
4771
4772 private Candidate(MethodResolutionPhase step, Symbol sym, JCDiagnostic details, Type mtype) {
4773 this.step = step;
4774 this.sym = sym;
4775 this.details = details;
4776 this.mtype = mtype;
4777 }
4778
4779 boolean isApplicable() {
4780 return mtype != null;
4781 }
4782 }
4783
4784 DeferredAttr.AttrMode attrMode() {
4785 return attrMode;
4786 }
4787
4788 boolean internal() {
4789 return internalResolution;
4790 }
4791 }
4792
4793 MethodResolutionContext currentResolutionContext = null;
4794 }