1 /*
2 * Copyright (c) 1999, 2024, 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.Resolve.MethodResolutionContext.Candidate;
40 import com.sun.tools.javac.comp.Resolve.MethodResolutionDiagHelper.Template;
41 import com.sun.tools.javac.comp.Resolve.ReferenceLookupResult.StaticKind;
42 import com.sun.tools.javac.jvm.*;
43 import com.sun.tools.javac.main.Option;
44 import com.sun.tools.javac.resources.CompilerProperties.Errors;
45 import com.sun.tools.javac.resources.CompilerProperties.Fragments;
46 import com.sun.tools.javac.resources.CompilerProperties.Warnings;
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.Map;
64 import java.util.Set;
65 import java.util.function.BiFunction;
66 import java.util.function.BiPredicate;
67 import java.util.function.Function;
68 import java.util.function.Predicate;
69 import java.util.function.UnaryOperator;
70 import java.util.stream.Stream;
71 import java.util.stream.StreamSupport;
72
73 import javax.lang.model.element.ElementVisitor;
74
75 import static com.sun.tools.javac.code.Flags.*;
76 import static com.sun.tools.javac.code.Flags.BLOCK;
77 import static com.sun.tools.javac.code.Flags.STATIC;
78 import static com.sun.tools.javac.code.Kinds.*;
79 import static com.sun.tools.javac.code.Kinds.Kind.*;
80 import static com.sun.tools.javac.code.TypeTag.*;
81 import static com.sun.tools.javac.comp.Resolve.MethodResolutionPhase.*;
82 import static com.sun.tools.javac.main.Option.DOE;
83 import static com.sun.tools.javac.tree.JCTree.Tag.*;
84 import static com.sun.tools.javac.util.Iterators.createCompoundIterator;
85
86 /** Helper class for name resolution, used mostly by the attribution phase.
87 *
88 * <p><b>This is NOT part of any supported API.
89 * If you write code that depends on this, you do so at your own risk.
90 * This code and its internal interfaces are subject to change or
91 * deletion without notice.</b>
92 */
93 public class Resolve {
94 protected static final Context.Key<Resolve> resolveKey = new Context.Key<>();
95
96 Names names;
97 Log log;
98 Symtab syms;
99 Attr attr;
100 AttrRecover attrRecover;
101 DeferredAttr deferredAttr;
102 Check chk;
103 Infer infer;
104 Preview preview;
105 ClassFinder finder;
106 ModuleFinder moduleFinder;
107 Types types;
108 JCDiagnostic.Factory diags;
109 public final boolean allowModules;
110 public final boolean allowRecords;
111 private final boolean compactMethodDiags;
112 private final boolean allowLocalVariableTypeInference;
113 private final boolean allowYieldStatement;
114 final EnumSet<VerboseResolutionMode> verboseResolutionMode;
115 final boolean dumpMethodReferenceSearchResults;
116 final boolean dumpStacktraceOnError;
117
118 WriteableScope polymorphicSignatureScope;
119
120 @SuppressWarnings("this-escape")
121 protected Resolve(Context context) {
122 context.put(resolveKey, this);
123 syms = Symtab.instance(context);
124
125 varNotFound = new SymbolNotFoundError(ABSENT_VAR);
126 methodNotFound = new SymbolNotFoundError(ABSENT_MTH);
127 typeNotFound = new SymbolNotFoundError(ABSENT_TYP);
128 referenceNotFound = ReferenceLookupResult.error(methodNotFound);
129
130 names = Names.instance(context);
131 log = Log.instance(context);
132 attr = Attr.instance(context);
133 attrRecover = AttrRecover.instance(context);
134 deferredAttr = DeferredAttr.instance(context);
135 chk = Check.instance(context);
136 infer = Infer.instance(context);
137 finder = ClassFinder.instance(context);
138 moduleFinder = ModuleFinder.instance(context);
139 types = Types.instance(context);
140 diags = JCDiagnostic.Factory.instance(context);
141 preview = Preview.instance(context);
142 Source source = Source.instance(context);
143 Options options = Options.instance(context);
144 compactMethodDiags = options.isSet(Option.XDIAGS, "compact") ||
145 options.isUnset(Option.XDIAGS) && options.isUnset("rawDiagnostics");
146 verboseResolutionMode = VerboseResolutionMode.getVerboseResolutionMode(options);
147 Target target = Target.instance(context);
148 allowLocalVariableTypeInference = Feature.LOCAL_VARIABLE_TYPE_INFERENCE.allowedInSource(source);
149 allowYieldStatement = Feature.SWITCH_EXPRESSION.allowedInSource(source);
150 polymorphicSignatureScope = WriteableScope.create(syms.noSymbol);
151 allowModules = Feature.MODULES.allowedInSource(source);
152 allowRecords = Feature.RECORDS.allowedInSource(source);
153 dumpMethodReferenceSearchResults = options.isSet("debug.dumpMethodReferenceSearchResults");
154 dumpStacktraceOnError = options.isSet("dev") || options.isSet(DOE);
155 }
156
157 /** error symbols, which are returned when resolution fails
158 */
159 private final SymbolNotFoundError varNotFound;
160 private final SymbolNotFoundError methodNotFound;
161 private final SymbolNotFoundError typeNotFound;
162
163 /** empty reference lookup result */
164 private final ReferenceLookupResult referenceNotFound;
165
166 public static Resolve instance(Context context) {
167 Resolve instance = context.get(resolveKey);
168 if (instance == null)
169 instance = new Resolve(context);
170 return instance;
171 }
172
173 private static Symbol bestOf(Symbol s1,
174 Symbol s2) {
175 return s1.kind.betterThan(s2.kind) ? s1 : s2;
176 }
177
178 // <editor-fold defaultstate="collapsed" desc="Verbose resolution diagnostics support">
179 enum VerboseResolutionMode {
180 SUCCESS("success"),
181 FAILURE("failure"),
182 APPLICABLE("applicable"),
183 INAPPLICABLE("inapplicable"),
184 DEFERRED_INST("deferred-inference"),
185 PREDEF("predef"),
186 OBJECT_INIT("object-init"),
187 INTERNAL("internal");
188
189 final String opt;
190
191 private VerboseResolutionMode(String opt) {
192 this.opt = opt;
193 }
194
195 static EnumSet<VerboseResolutionMode> getVerboseResolutionMode(Options opts) {
196 String s = opts.get("debug.verboseResolution");
197 EnumSet<VerboseResolutionMode> res = EnumSet.noneOf(VerboseResolutionMode.class);
198 if (s == null) return res;
199 if (s.contains("all")) {
200 res = EnumSet.allOf(VerboseResolutionMode.class);
201 }
202 Collection<String> args = Arrays.asList(s.split(","));
203 for (VerboseResolutionMode mode : values()) {
204 if (args.contains(mode.opt)) {
205 res.add(mode);
206 } else if (args.contains("-" + mode.opt)) {
207 res.remove(mode);
208 }
209 }
210 return res;
211 }
212 }
213
214 void reportVerboseResolutionDiagnostic(DiagnosticPosition dpos, Name name, Type site,
215 List<Type> argtypes, List<Type> typeargtypes, Symbol bestSoFar) {
216 boolean success = !bestSoFar.kind.isResolutionError();
217
218 if (success && !verboseResolutionMode.contains(VerboseResolutionMode.SUCCESS)) {
219 return;
220 } else if (!success && !verboseResolutionMode.contains(VerboseResolutionMode.FAILURE)) {
221 return;
222 }
223
224 if (bestSoFar.name == names.init &&
225 bestSoFar.owner == syms.objectType.tsym &&
226 !verboseResolutionMode.contains(VerboseResolutionMode.OBJECT_INIT)) {
227 return; //skip diags for Object constructor resolution
228 } else if (site == syms.predefClass.type &&
229 !verboseResolutionMode.contains(VerboseResolutionMode.PREDEF)) {
230 return; //skip spurious diags for predef symbols (i.e. operators)
231 } else if (currentResolutionContext.internalResolution &&
232 !verboseResolutionMode.contains(VerboseResolutionMode.INTERNAL)) {
233 return;
234 }
235
236 int pos = 0;
237 int mostSpecificPos = -1;
238 ListBuffer<JCDiagnostic> subDiags = new ListBuffer<>();
239 for (Candidate c : currentResolutionContext.candidates) {
240 if (currentResolutionContext.step != c.step ||
241 (c.isApplicable() && !verboseResolutionMode.contains(VerboseResolutionMode.APPLICABLE)) ||
242 (!c.isApplicable() && !verboseResolutionMode.contains(VerboseResolutionMode.INAPPLICABLE))) {
243 continue;
244 } else {
245 subDiags.append(c.isApplicable() ?
246 getVerboseApplicableCandidateDiag(pos, c.sym, c.mtype) :
247 getVerboseInapplicableCandidateDiag(pos, c.sym, c.details));
248 if (c.sym == bestSoFar)
249 mostSpecificPos = pos;
250 pos++;
251 }
252 }
253 String key = success ? "verbose.resolve.multi" : "verbose.resolve.multi.1";
254 List<Type> argtypes2 = argtypes.map(deferredAttr.new RecoveryDeferredTypeMap(AttrMode.SPECULATIVE, bestSoFar, currentResolutionContext.step));
255 JCDiagnostic main = diags.note(log.currentSource(), dpos, key, name,
256 site.tsym, mostSpecificPos, currentResolutionContext.step,
257 methodArguments(argtypes2),
258 methodArguments(typeargtypes));
259 JCDiagnostic d = new JCDiagnostic.MultilineDiagnostic(main, subDiags.toList());
260 log.report(d);
261 }
262
263 JCDiagnostic getVerboseApplicableCandidateDiag(int pos, Symbol sym, Type inst) {
264 JCDiagnostic subDiag = null;
265 if (sym.type.hasTag(FORALL)) {
266 subDiag = diags.fragment(Fragments.PartialInstSig(inst));
267 }
268
269 String key = subDiag == null ?
270 "applicable.method.found" :
271 "applicable.method.found.1";
272
273 return diags.fragment(key, pos, sym, subDiag);
274 }
275
276 JCDiagnostic getVerboseInapplicableCandidateDiag(int pos, Symbol sym, JCDiagnostic subDiag) {
277 return diags.fragment(Fragments.NotApplicableMethodFound(pos, sym, subDiag));
278 }
279 // </editor-fold>
280
281 /* ************************************************************************
282 * Identifier resolution
283 *************************************************************************/
284
285 /** An environment is "static" if its static level is greater than
286 * the one of its outer environment
287 */
288 protected static boolean isStatic(Env<AttrContext> env) {
289 return env.outer != null && env.info.staticLevel > env.outer.info.staticLevel;
290 }
291
292 /** An environment is an "initializer" if it is a constructor or
293 * an instance initializer.
294 */
295 static boolean isInitializer(Env<AttrContext> env) {
296 Symbol owner = env.info.scope.owner;
297 return owner.isConstructor() ||
298 owner.owner.kind == TYP &&
299 (owner.kind == VAR ||
300 owner.kind == MTH && (owner.flags() & BLOCK) != 0) &&
301 (owner.flags() & STATIC) == 0;
302 }
303
304 /** Is class accessible in given environment?
305 * @param env The current environment.
306 * @param c The class whose accessibility is checked.
307 */
308 public boolean isAccessible(Env<AttrContext> env, TypeSymbol c) {
309 return isAccessible(env, c, false);
310 }
311
312 public boolean isAccessible(Env<AttrContext> env, TypeSymbol c, boolean checkInner) {
313
314 /* 15.9.5.1: Note that it is possible for the signature of the anonymous constructor
315 to refer to an inaccessible type
316 */
317 if (env.enclMethod != null && (env.enclMethod.mods.flags & ANONCONSTR) != 0)
318 return true;
319
320 if (env.info.visitingServiceImplementation &&
321 env.toplevel.modle == c.packge().modle) {
322 return true;
323 }
324
325 boolean isAccessible = false;
326 switch ((short)(c.flags() & AccessFlags)) {
327 case PRIVATE:
328 isAccessible =
329 env.enclClass.sym.outermostClass() ==
330 c.owner.outermostClass();
331 break;
332 case 0:
333 isAccessible =
334 env.toplevel.packge == c.owner // fast special case
335 ||
336 env.toplevel.packge == c.packge();
337 break;
338 default: // error recovery
339 isAccessible = true;
340 break;
341 case PUBLIC:
342 if (allowModules) {
343 ModuleSymbol currModule = env.toplevel.modle;
344 currModule.complete();
345 PackageSymbol p = c.packge();
346 isAccessible =
347 currModule == p.modle ||
348 currModule.visiblePackages.get(p.fullname) == p ||
349 p == syms.rootPackage ||
350 (p.modle == syms.unnamedModule && currModule.readModules.contains(p.modle));
351 } else {
352 isAccessible = true;
353 }
354 break;
355 case PROTECTED:
356 isAccessible =
357 env.toplevel.packge == c.owner // fast special case
358 ||
359 env.toplevel.packge == c.packge()
360 ||
361 isInnerSubClass(env.enclClass.sym, c.owner)
362 ||
363 env.info.allowProtectedAccess;
364 break;
365 }
366 return (checkInner == false || c.type.getEnclosingType() == Type.noType) ?
367 isAccessible :
368 isAccessible && isAccessible(env, c.type.getEnclosingType(), checkInner);
369 }
370 //where
371 /** Is given class a subclass of given base class, or an inner class
372 * of a subclass?
373 * Return null if no such class exists.
374 * @param c The class which is the subclass or is contained in it.
375 * @param base The base class
376 */
377 private boolean isInnerSubClass(ClassSymbol c, Symbol base) {
378 while (c != null && !c.isSubClass(base, types)) {
379 c = c.owner.enclClass();
380 }
381 return c != null;
382 }
383
384 boolean isAccessible(Env<AttrContext> env, Type t) {
385 return isAccessible(env, t, false);
386 }
387
388 boolean isAccessible(Env<AttrContext> env, Type t, boolean checkInner) {
389 if (t.hasTag(ARRAY)) {
390 return isAccessible(env, types.cvarUpperBound(types.elemtype(t)));
391 } else if (t.isUnion()) {
392 return StreamSupport.stream(((UnionClassType) t).getAlternativeTypes().spliterator(), false)
393 .allMatch(alternative -> isAccessible(env, alternative.tsym, checkInner));
394 } else {
395 return isAccessible(env, t.tsym, checkInner);
396 }
397 }
398
399 /** Is symbol accessible as a member of given type in given environment?
400 * @param env The current environment.
401 * @param site The type of which the tested symbol is regarded
402 * as a member.
403 * @param sym The symbol.
404 */
405 public boolean isAccessible(Env<AttrContext> env, Type site, Symbol sym) {
406 return isAccessible(env, site, sym, false);
407 }
408 public boolean isAccessible(Env<AttrContext> env, Type site, Symbol sym, boolean checkInner) {
409 if (sym.name == names.init && sym.owner != site.tsym) return false;
410
411 /* 15.9.5.1: Note that it is possible for the signature of the anonymous constructor
412 to refer to an inaccessible type
413 */
414 if (env.enclMethod != null && (env.enclMethod.mods.flags & ANONCONSTR) != 0)
415 return true;
416
417 if (env.info.visitingServiceImplementation &&
418 env.toplevel.modle == sym.packge().modle) {
419 return true;
420 }
421
422 switch ((short)(sym.flags() & AccessFlags)) {
423 case PRIVATE:
424 return
425 (env.enclClass.sym == sym.owner // fast special case
426 ||
427 env.enclClass.sym.outermostClass() ==
428 sym.owner.outermostClass())
429 &&
430 sym.isInheritedIn(site.tsym, types);
431 case 0:
432 return
433 (env.toplevel.packge == sym.owner.owner // fast special case
434 ||
435 env.toplevel.packge == sym.packge())
436 &&
437 isAccessible(env, site, checkInner)
438 &&
439 sym.isInheritedIn(site.tsym, types)
440 &&
441 notOverriddenIn(site, sym);
442 case PROTECTED:
443 return
444 (env.toplevel.packge == sym.owner.owner // fast special case
445 ||
446 env.toplevel.packge == sym.packge()
447 ||
448 isProtectedAccessible(sym, env.enclClass.sym, site)
449 ||
450 // OK to select instance method or field from 'super' or type name
451 // (but type names should be disallowed elsewhere!)
452 env.info.selectSuper && (sym.flags() & STATIC) == 0 && sym.kind != TYP)
453 &&
454 isAccessible(env, site, checkInner)
455 &&
456 notOverriddenIn(site, sym);
457 default: // this case includes erroneous combinations as well
458 return isAccessible(env, site, checkInner) && notOverriddenIn(site, sym);
459 }
460 }
461 //where
462 /* `sym' is accessible only if not overridden by
463 * another symbol which is a member of `site'
464 * (because, if it is overridden, `sym' is not strictly
465 * speaking a member of `site'). A polymorphic signature method
466 * cannot be overridden (e.g. MH.invokeExact(Object[])).
467 */
468 private boolean notOverriddenIn(Type site, Symbol sym) {
469 if (sym.kind != MTH || sym.isConstructor() || sym.isStatic())
470 return true;
471 else {
472 Symbol s2 = ((MethodSymbol)sym).implementation(site.tsym, types, true);
473 return (s2 == null || s2 == sym || sym.owner == s2.owner || (sym.owner.isInterface() && s2.owner == syms.objectType.tsym) ||
474 !types.isSubSignature(types.memberType(site, s2), types.memberType(site, sym)));
475 }
476 }
477 //where
478 /** Is given protected symbol accessible if it is selected from given site
479 * and the selection takes place in given class?
480 * @param sym The symbol with protected access
481 * @param c The class where the access takes place
482 * @param site The type of the qualifier
483 */
484 private
485 boolean isProtectedAccessible(Symbol sym, ClassSymbol c, Type site) {
486 Type newSite = site.hasTag(TYPEVAR) ? site.getUpperBound() : site;
487 while (c != null &&
488 !(c.isSubClass(sym.owner, types) &&
489 (c.flags() & INTERFACE) == 0 &&
490 // In JLS 2e 6.6.2.1, the subclass restriction applies
491 // only to instance fields and methods -- types are excluded
492 // regardless of whether they are declared 'static' or not.
493 ((sym.flags() & STATIC) != 0 || sym.kind == TYP || newSite.tsym.isSubClass(c, types))))
494 c = c.owner.enclClass();
495 return c != null;
496 }
497
498 /**
499 * Performs a recursive scan of a type looking for accessibility problems
500 * from current attribution environment
501 */
502 void checkAccessibleType(Env<AttrContext> env, Type t) {
503 accessibilityChecker.visit(t, env);
504 }
505
506 /**
507 * Accessibility type-visitor
508 */
509 Types.SimpleVisitor<Void, Env<AttrContext>> accessibilityChecker =
510 new Types.SimpleVisitor<Void, Env<AttrContext>>() {
511
512 void visit(List<Type> ts, Env<AttrContext> env) {
513 for (Type t : ts) {
514 visit(t, env);
515 }
516 }
517
518 public Void visitType(Type t, Env<AttrContext> env) {
519 return null;
520 }
521
522 @Override
523 public Void visitArrayType(ArrayType t, Env<AttrContext> env) {
524 visit(t.elemtype, env);
525 return null;
526 }
527
528 @Override
529 public Void visitClassType(ClassType t, Env<AttrContext> env) {
530 visit(t.getTypeArguments(), env);
531 if (!isAccessible(env, t, true)) {
532 accessBase(new AccessError(env, null, t.tsym), env.tree.pos(), env.enclClass.sym, t, t.tsym.name, true);
533 }
534 return null;
535 }
536
537 @Override
538 public Void visitWildcardType(WildcardType t, Env<AttrContext> env) {
539 visit(t.type, env);
540 return null;
541 }
542
543 @Override
544 public Void visitMethodType(MethodType t, Env<AttrContext> env) {
545 visit(t.getParameterTypes(), env);
546 visit(t.getReturnType(), env);
547 visit(t.getThrownTypes(), env);
548 return null;
549 }
550 };
551
552 /** Try to instantiate the type of a method so that it fits
553 * given type arguments and argument types. If successful, return
554 * the method's instantiated type, else return null.
555 * The instantiation will take into account an additional leading
556 * formal parameter if the method is an instance method seen as a member
557 * of an under determined site. In this case, we treat site as an additional
558 * parameter and the parameters of the class containing the method as
559 * additional type variables that get instantiated.
560 *
561 * @param env The current environment
562 * @param site The type of which the method is a member.
563 * @param m The method symbol.
564 * @param argtypes The invocation's given value arguments.
565 * @param typeargtypes The invocation's given type arguments.
566 * @param allowBoxing Allow boxing conversions of arguments.
567 * @param useVarargs Box trailing arguments into an array for varargs.
568 */
569 Type rawInstantiate(Env<AttrContext> env,
570 Type site,
571 Symbol m,
572 ResultInfo resultInfo,
573 List<Type> argtypes,
574 List<Type> typeargtypes,
575 boolean allowBoxing,
576 boolean useVarargs,
577 Warner warn) throws Infer.InferenceException {
578 Type mt = types.memberType(site, m);
579 // tvars is the list of formal type variables for which type arguments
580 // need to inferred.
581 List<Type> tvars = List.nil();
582 if (typeargtypes == null) typeargtypes = List.nil();
583 if (!mt.hasTag(FORALL) && typeargtypes.nonEmpty()) {
584 // This is not a polymorphic method, but typeargs are supplied
585 // which is fine, see JLS 15.12.2.1
586 } else if (mt.hasTag(FORALL) && typeargtypes.nonEmpty()) {
587 ForAll pmt = (ForAll) mt;
588 if (typeargtypes.length() != pmt.tvars.length())
589 // not enough args
590 throw new InapplicableMethodException(diags.fragment(Fragments.WrongNumberTypeArgs(Integer.toString(pmt.tvars.length()))), dumpStacktraceOnError);
591 // Check type arguments are within bounds
592 List<Type> formals = pmt.tvars;
593 List<Type> actuals = typeargtypes;
594 while (formals.nonEmpty() && actuals.nonEmpty()) {
595 List<Type> bounds = types.subst(types.getBounds((TypeVar)formals.head),
596 pmt.tvars, typeargtypes);
597 for (; bounds.nonEmpty(); bounds = bounds.tail) {
598 if (!types.isSubtypeUnchecked(actuals.head, bounds.head, warn)) {
599 throw new InapplicableMethodException(diags.fragment(Fragments.ExplicitParamDoNotConformToBounds(actuals.head, bounds)), dumpStacktraceOnError);
600 }
601 }
602 formals = formals.tail;
603 actuals = actuals.tail;
604 }
605 mt = types.subst(pmt.qtype, pmt.tvars, typeargtypes);
606 } else if (mt.hasTag(FORALL)) {
607 ForAll pmt = (ForAll) mt;
608 List<Type> tvars1 = types.newInstances(pmt.tvars);
609 tvars = tvars.appendList(tvars1);
610 mt = types.subst(pmt.qtype, pmt.tvars, tvars1);
611 }
612
613 // find out whether we need to go the slow route via infer
614 boolean instNeeded = tvars.tail != null; /*inlined: tvars.nonEmpty()*/
615 for (List<Type> l = argtypes;
616 l.tail != null/*inlined: l.nonEmpty()*/ && !instNeeded;
617 l = l.tail) {
618 if (l.head.hasTag(FORALL)) instNeeded = true;
619 }
620
621 if (instNeeded) {
622 return infer.instantiateMethod(env,
623 tvars,
624 (MethodType)mt,
625 resultInfo,
626 (MethodSymbol)m,
627 argtypes,
628 allowBoxing,
629 useVarargs,
630 currentResolutionContext,
631 warn);
632 }
633
634 DeferredAttr.DeferredAttrContext dc = currentResolutionContext.deferredAttrContext(m, infer.emptyContext, resultInfo, warn);
635 currentResolutionContext.methodCheck.argumentsAcceptable(env, dc,
636 argtypes, mt.getParameterTypes(), warn);
637 dc.complete();
638 return mt;
639 }
640
641 Type checkMethod(Env<AttrContext> env,
642 Type site,
643 Symbol m,
644 ResultInfo resultInfo,
645 List<Type> argtypes,
646 List<Type> typeargtypes,
647 Warner warn) {
648 MethodResolutionContext prevContext = currentResolutionContext;
649 try {
650 currentResolutionContext = new MethodResolutionContext();
651 currentResolutionContext.attrMode = (resultInfo.pt == Infer.anyPoly) ?
652 AttrMode.SPECULATIVE : DeferredAttr.AttrMode.CHECK;
653 if (env.tree.hasTag(JCTree.Tag.REFERENCE)) {
654 //method/constructor references need special check class
655 //to handle inference variables in 'argtypes' (might happen
656 //during an unsticking round)
657 currentResolutionContext.methodCheck =
658 new MethodReferenceCheck(resultInfo.checkContext.inferenceContext());
659 }
660 MethodResolutionPhase step = currentResolutionContext.step = env.info.pendingResolutionPhase;
661 return rawInstantiate(env, site, m, resultInfo, argtypes, typeargtypes,
662 step.isBoxingRequired(), step.isVarargsRequired(), warn);
663 }
664 finally {
665 currentResolutionContext = prevContext;
666 }
667 }
668
669 /** Same but returns null instead throwing a NoInstanceException
670 */
671 Type instantiate(Env<AttrContext> env,
672 Type site,
673 Symbol m,
674 ResultInfo resultInfo,
675 List<Type> argtypes,
676 List<Type> typeargtypes,
677 boolean allowBoxing,
678 boolean useVarargs,
679 Warner warn) {
680 try {
681 return rawInstantiate(env, site, m, resultInfo, argtypes, typeargtypes,
682 allowBoxing, useVarargs, warn);
683 } catch (InapplicableMethodException ex) {
684 return null;
685 }
686 }
687
688 /**
689 * This interface defines an entry point that should be used to perform a
690 * method check. A method check usually consist in determining as to whether
691 * a set of types (actuals) is compatible with another set of types (formals).
692 * Since the notion of compatibility can vary depending on the circumstances,
693 * this interfaces allows to easily add new pluggable method check routines.
694 */
695 interface MethodCheck {
696 /**
697 * Main method check routine. A method check usually consist in determining
698 * as to whether a set of types (actuals) is compatible with another set of
699 * types (formals). If an incompatibility is found, an unchecked exception
700 * is assumed to be thrown.
701 */
702 void argumentsAcceptable(Env<AttrContext> env,
703 DeferredAttrContext deferredAttrContext,
704 List<Type> argtypes,
705 List<Type> formals,
706 Warner warn);
707
708 /**
709 * Retrieve the method check object that will be used during a
710 * most specific check.
711 */
712 MethodCheck mostSpecificCheck(List<Type> actuals);
713 }
714
715 /**
716 * Helper enum defining all method check diagnostics (used by resolveMethodCheck).
717 */
718 enum MethodCheckDiag {
719 /**
720 * Actuals and formals differs in length.
721 */
722 ARITY_MISMATCH("arg.length.mismatch", "infer.arg.length.mismatch"),
723 /**
724 * An actual is incompatible with a formal.
725 */
726 ARG_MISMATCH("no.conforming.assignment.exists", "infer.no.conforming.assignment.exists"),
727 /**
728 * An actual is incompatible with the varargs element type.
729 */
730 VARARG_MISMATCH("varargs.argument.mismatch", "infer.varargs.argument.mismatch"),
731 /**
732 * The varargs element type is inaccessible.
733 */
734 INACCESSIBLE_VARARGS("inaccessible.varargs.type", "inaccessible.varargs.type");
735
736 final String basicKey;
737 final String inferKey;
738
739 MethodCheckDiag(String basicKey, String inferKey) {
740 this.basicKey = basicKey;
741 this.inferKey = inferKey;
742 }
743
744 String regex() {
745 return String.format("([a-z]*\\.)*(%s|%s)", basicKey, inferKey);
746 }
747 }
748
749 /**
750 * Dummy method check object. All methods are deemed applicable, regardless
751 * of their formal parameter types.
752 */
753 MethodCheck nilMethodCheck = new MethodCheck() {
754 public void argumentsAcceptable(Env<AttrContext> env, DeferredAttrContext deferredAttrContext, List<Type> argtypes, List<Type> formals, Warner warn) {
755 //do nothing - method always applicable regardless of actuals
756 }
757
758 public MethodCheck mostSpecificCheck(List<Type> actuals) {
759 return this;
760 }
761 };
762
763 /**
764 * Base class for 'real' method checks. The class defines the logic for
765 * iterating through formals and actuals and provides and entry point
766 * that can be used by subclasses in order to define the actual check logic.
767 */
768 abstract class AbstractMethodCheck implements MethodCheck {
769 @Override
770 public void argumentsAcceptable(final Env<AttrContext> env,
771 DeferredAttrContext deferredAttrContext,
772 List<Type> argtypes,
773 List<Type> formals,
774 Warner warn) {
775 //should we expand formals?
776 boolean useVarargs = deferredAttrContext.phase.isVarargsRequired();
777 JCTree callTree = treeForDiagnostics(env);
778 List<JCExpression> trees = TreeInfo.args(callTree);
779
780 //inference context used during this method check
781 InferenceContext inferenceContext = deferredAttrContext.inferenceContext;
782
783 Type varargsFormal = useVarargs ? formals.last() : null;
784
785 if (varargsFormal == null &&
786 argtypes.size() != formals.size()) {
787 reportMC(callTree, MethodCheckDiag.ARITY_MISMATCH, inferenceContext); // not enough args
788 }
789
790 while (argtypes.nonEmpty() && formals.head != varargsFormal) {
791 DiagnosticPosition pos = trees != null ? trees.head : null;
792 checkArg(pos, false, argtypes.head, formals.head, deferredAttrContext, warn);
793 argtypes = argtypes.tail;
794 formals = formals.tail;
795 trees = trees != null ? trees.tail : trees;
796 }
797
798 if (formals.head != varargsFormal) {
799 reportMC(callTree, MethodCheckDiag.ARITY_MISMATCH, inferenceContext); // not enough args
800 }
801
802 if (useVarargs) {
803 //note: if applicability check is triggered by most specific test,
804 //the last argument of a varargs is _not_ an array type (see JLS 15.12.2.5)
805 final Type elt = types.elemtype(varargsFormal);
806 while (argtypes.nonEmpty()) {
807 DiagnosticPosition pos = trees != null ? trees.head : null;
808 checkArg(pos, true, argtypes.head, elt, deferredAttrContext, warn);
809 argtypes = argtypes.tail;
810 trees = trees != null ? trees.tail : trees;
811 }
812 }
813 }
814
815 // where
816 private JCTree treeForDiagnostics(Env<AttrContext> env) {
817 return env.info.preferredTreeForDiagnostics != null ? env.info.preferredTreeForDiagnostics : env.tree;
818 }
819
820 /**
821 * Does the actual argument conforms to the corresponding formal?
822 */
823 abstract void checkArg(DiagnosticPosition pos, boolean varargs, Type actual, Type formal, DeferredAttrContext deferredAttrContext, Warner warn);
824
825 protected void reportMC(DiagnosticPosition pos, MethodCheckDiag diag, InferenceContext inferenceContext, Object... args) {
826 boolean inferDiag = inferenceContext != infer.emptyContext;
827 if (inferDiag && (!diag.inferKey.equals(diag.basicKey))) {
828 Object[] args2 = new Object[args.length + 1];
829 System.arraycopy(args, 0, args2, 1, args.length);
830 args2[0] = inferenceContext.inferenceVars();
831 args = args2;
832 }
833 String key = inferDiag ? diag.inferKey : diag.basicKey;
834 throw inferDiag ?
835 infer.error(diags.create(DiagnosticType.FRAGMENT, log.currentSource(), pos, key, args)) :
836 getMethodCheckFailure().setMessage(diags.create(DiagnosticType.FRAGMENT, log.currentSource(), pos, key, args));
837 }
838
839 /**
840 * To eliminate the overhead associated with allocating an exception object in such an
841 * hot execution path, we use flyweight pattern - and share the same exception instance
842 * across multiple method check failures.
843 */
844 class SharedInapplicableMethodException extends InapplicableMethodException {
845 private static final long serialVersionUID = 0;
846
847 SharedInapplicableMethodException() {
848 super(null, Resolve.this.dumpStacktraceOnError);
849 }
850
851 SharedInapplicableMethodException setMessage(JCDiagnostic details) {
852 this.diagnostic = details;
853 return this;
854 }
855 }
856
857 private SharedInapplicableMethodException methodCheckFailure;
858
859 public MethodCheck mostSpecificCheck(List<Type> actuals) {
860 return nilMethodCheck;
861 }
862
863 private SharedInapplicableMethodException getMethodCheckFailure() {
864 return methodCheckFailure == null ? methodCheckFailure = new SharedInapplicableMethodException() : methodCheckFailure;
865 }
866 }
867
868 /**
869 * Arity-based method check. A method is applicable if the number of actuals
870 * supplied conforms to the method signature.
871 */
872 MethodCheck arityMethodCheck = new AbstractMethodCheck() {
873 @Override
874 void checkArg(DiagnosticPosition pos, boolean varargs, Type actual, Type formal, DeferredAttrContext deferredAttrContext, Warner warn) {
875 //do nothing - actual always compatible to formals
876 }
877
878 @Override
879 public String toString() {
880 return "arityMethodCheck";
881 }
882 };
883
884 /**
885 * Main method applicability routine. Given a list of actual types A,
886 * a list of formal types F, determines whether the types in A are
887 * compatible (by method invocation conversion) with the types in F.
888 *
889 * Since this routine is shared between overload resolution and method
890 * type-inference, a (possibly empty) inference context is used to convert
891 * formal types to the corresponding 'undet' form ahead of a compatibility
892 * check so that constraints can be propagated and collected.
893 *
894 * Moreover, if one or more types in A is a deferred type, this routine uses
895 * DeferredAttr in order to perform deferred attribution. If one or more actual
896 * deferred types are stuck, they are placed in a queue and revisited later
897 * after the remainder of the arguments have been seen. If this is not sufficient
898 * to 'unstuck' the argument, a cyclic inference error is called out.
899 *
900 * A method check handler (see above) is used in order to report errors.
901 */
902 MethodCheck resolveMethodCheck = new AbstractMethodCheck() {
903
904 @Override
905 void checkArg(DiagnosticPosition pos, boolean varargs, Type actual, Type formal, DeferredAttrContext deferredAttrContext, Warner warn) {
906 ResultInfo mresult = methodCheckResult(varargs, formal, deferredAttrContext, warn);
907 mresult.check(pos, actual);
908 }
909
910 @Override
911 public void argumentsAcceptable(final Env<AttrContext> env,
912 DeferredAttrContext deferredAttrContext,
913 List<Type> argtypes,
914 List<Type> formals,
915 Warner warn) {
916 super.argumentsAcceptable(env, deferredAttrContext, argtypes, formals, warn);
917 // should we check varargs element type accessibility?
918 if (deferredAttrContext.phase.isVarargsRequired()) {
919 if (deferredAttrContext.mode == AttrMode.CHECK) {
920 varargsAccessible(env, types.elemtype(formals.last()), deferredAttrContext.inferenceContext);
921 }
922 }
923 }
924
925 /**
926 * Test that the runtime array element type corresponding to 't' is accessible. 't' should be the
927 * varargs element type of either the method invocation type signature (after inference completes)
928 * or the method declaration signature (before inference completes).
929 */
930 private void varargsAccessible(final Env<AttrContext> env, final Type t, final InferenceContext inferenceContext) {
931 if (inferenceContext.free(t)) {
932 inferenceContext.addFreeTypeListener(List.of(t),
933 solvedContext -> varargsAccessible(env, solvedContext.asInstType(t), solvedContext));
934 } else {
935 if (!isAccessible(env, types.erasure(t))) {
936 Symbol location = env.enclClass.sym;
937 reportMC(env.tree, MethodCheckDiag.INACCESSIBLE_VARARGS, inferenceContext, t, Kinds.kindName(location), location);
938 }
939 }
940 }
941
942 private ResultInfo methodCheckResult(final boolean varargsCheck, Type to,
943 final DeferredAttr.DeferredAttrContext deferredAttrContext, Warner rsWarner) {
944 CheckContext checkContext = new MethodCheckContext(!deferredAttrContext.phase.isBoxingRequired(), deferredAttrContext, rsWarner) {
945 MethodCheckDiag methodDiag = varargsCheck ?
946 MethodCheckDiag.VARARG_MISMATCH : MethodCheckDiag.ARG_MISMATCH;
947
948 @Override
949 public void report(DiagnosticPosition pos, JCDiagnostic details) {
950 reportMC(pos, methodDiag, deferredAttrContext.inferenceContext, details);
951 }
952 };
953 return new MethodResultInfo(to, checkContext);
954 }
955
956 @Override
957 public MethodCheck mostSpecificCheck(List<Type> actuals) {
958 return new MostSpecificCheck(actuals);
959 }
960
961 @Override
962 public String toString() {
963 return "resolveMethodCheck";
964 }
965 };
966
967 /**
968 * This class handles method reference applicability checks; since during
969 * these checks it's sometime possible to have inference variables on
970 * the actual argument types list, the method applicability check must be
971 * extended so that inference variables are 'opened' as needed.
972 */
973 class MethodReferenceCheck extends AbstractMethodCheck {
974
975 InferenceContext pendingInferenceContext;
976
977 MethodReferenceCheck(InferenceContext pendingInferenceContext) {
978 this.pendingInferenceContext = pendingInferenceContext;
979 }
980
981 @Override
982 void checkArg(DiagnosticPosition pos, boolean varargs, Type actual, Type formal, DeferredAttrContext deferredAttrContext, Warner warn) {
983 ResultInfo mresult = methodCheckResult(varargs, formal, deferredAttrContext, warn);
984 mresult.check(pos, actual);
985 }
986
987 private ResultInfo methodCheckResult(final boolean varargsCheck, Type to,
988 final DeferredAttr.DeferredAttrContext deferredAttrContext, Warner rsWarner) {
989 CheckContext checkContext = new MethodCheckContext(!deferredAttrContext.phase.isBoxingRequired(), deferredAttrContext, rsWarner) {
990 MethodCheckDiag methodDiag = varargsCheck ?
991 MethodCheckDiag.VARARG_MISMATCH : MethodCheckDiag.ARG_MISMATCH;
992
993 @Override
994 public boolean compatible(Type found, Type req, Warner warn) {
995 found = pendingInferenceContext.asUndetVar(found);
996 if (found.hasTag(UNDETVAR) && req.isPrimitive()) {
997 req = types.boxedClass(req).type;
998 }
999 return super.compatible(found, req, warn);
1000 }
1001
1002 @Override
1003 public void report(DiagnosticPosition pos, JCDiagnostic details) {
1004 reportMC(pos, methodDiag, deferredAttrContext.inferenceContext, details);
1005 }
1006 };
1007 return new MethodResultInfo(to, checkContext);
1008 }
1009
1010 @Override
1011 public MethodCheck mostSpecificCheck(List<Type> actuals) {
1012 return new MostSpecificCheck(actuals);
1013 }
1014
1015 @Override
1016 public String toString() {
1017 return "MethodReferenceCheck";
1018 }
1019 }
1020
1021 /**
1022 * Check context to be used during method applicability checks. A method check
1023 * context might contain inference variables.
1024 */
1025 abstract class MethodCheckContext implements CheckContext {
1026
1027 boolean strict;
1028 DeferredAttrContext deferredAttrContext;
1029 Warner rsWarner;
1030
1031 public MethodCheckContext(boolean strict, DeferredAttrContext deferredAttrContext, Warner rsWarner) {
1032 this.strict = strict;
1033 this.deferredAttrContext = deferredAttrContext;
1034 this.rsWarner = rsWarner;
1035 }
1036
1037 public boolean compatible(Type found, Type req, Warner warn) {
1038 InferenceContext inferenceContext = deferredAttrContext.inferenceContext;
1039 return strict ?
1040 types.isSubtypeUnchecked(inferenceContext.asUndetVar(found), inferenceContext.asUndetVar(req), warn) :
1041 types.isConvertible(inferenceContext.asUndetVar(found), inferenceContext.asUndetVar(req), warn);
1042 }
1043
1044 public void report(DiagnosticPosition pos, JCDiagnostic details) {
1045 throw new InapplicableMethodException(details, Resolve.this.dumpStacktraceOnError);
1046 }
1047
1048 public Warner checkWarner(DiagnosticPosition pos, Type found, Type req) {
1049 return rsWarner;
1050 }
1051
1052 public InferenceContext inferenceContext() {
1053 return deferredAttrContext.inferenceContext;
1054 }
1055
1056 public DeferredAttrContext deferredAttrContext() {
1057 return deferredAttrContext;
1058 }
1059
1060 @Override
1061 public String toString() {
1062 return "MethodCheckContext";
1063 }
1064 }
1065
1066 /**
1067 * ResultInfo class to be used during method applicability checks. Check
1068 * for deferred types goes through special path.
1069 */
1070 class MethodResultInfo extends ResultInfo {
1071
1072 public MethodResultInfo(Type pt, CheckContext checkContext) {
1073 attr.super(KindSelector.VAL, pt, checkContext);
1074 }
1075
1076 @Override
1077 protected Type check(DiagnosticPosition pos, Type found) {
1078 if (found.hasTag(DEFERRED)) {
1079 DeferredType dt = (DeferredType)found;
1080 return dt.check(this);
1081 } else {
1082 Type uResult = U(found);
1083 Type capturedType = pos == null || pos.getTree() == null ?
1084 types.capture(uResult) :
1085 checkContext.inferenceContext()
1086 .cachedCapture(pos.getTree(), uResult, true);
1087 return super.check(pos, chk.checkNonVoid(pos, capturedType));
1088 }
1089 }
1090
1091 /**
1092 * javac has a long-standing 'simplification' (see 6391995):
1093 * given an actual argument type, the method check is performed
1094 * on its upper bound. This leads to inconsistencies when an
1095 * argument type is checked against itself. For example, given
1096 * a type-variable T, it is not true that {@code U(T) <: T},
1097 * so we need to guard against that.
1098 */
1099 private Type U(Type found) {
1100 return found == pt ?
1101 found : types.cvarUpperBound(found);
1102 }
1103
1104 @Override
1105 protected MethodResultInfo dup(Type newPt) {
1106 return new MethodResultInfo(newPt, checkContext);
1107 }
1108
1109 @Override
1110 protected ResultInfo dup(CheckContext newContext) {
1111 return new MethodResultInfo(pt, newContext);
1112 }
1113
1114 @Override
1115 protected ResultInfo dup(Type newPt, CheckContext newContext) {
1116 return new MethodResultInfo(newPt, newContext);
1117 }
1118 }
1119
1120 /**
1121 * Most specific method applicability routine. Given a list of actual types A,
1122 * a list of formal types F1, and a list of formal types F2, the routine determines
1123 * as to whether the types in F1 can be considered more specific than those in F2 w.r.t.
1124 * argument types A.
1125 */
1126 class MostSpecificCheck implements MethodCheck {
1127
1128 List<Type> actuals;
1129
1130 MostSpecificCheck(List<Type> actuals) {
1131 this.actuals = actuals;
1132 }
1133
1134 @Override
1135 public void argumentsAcceptable(final Env<AttrContext> env,
1136 DeferredAttrContext deferredAttrContext,
1137 List<Type> formals1,
1138 List<Type> formals2,
1139 Warner warn) {
1140 formals2 = adjustArgs(formals2, deferredAttrContext.msym, formals1.length(), deferredAttrContext.phase.isVarargsRequired());
1141 while (formals2.nonEmpty()) {
1142 ResultInfo mresult = methodCheckResult(formals2.head, deferredAttrContext, warn, actuals.head);
1143 mresult.check(null, formals1.head);
1144 formals1 = formals1.tail;
1145 formals2 = formals2.tail;
1146 actuals = actuals.isEmpty() ? actuals : actuals.tail;
1147 }
1148 }
1149
1150 /**
1151 * Create a method check context to be used during the most specific applicability check
1152 */
1153 ResultInfo methodCheckResult(Type to, DeferredAttr.DeferredAttrContext deferredAttrContext,
1154 Warner rsWarner, Type actual) {
1155 return attr.new ResultInfo(KindSelector.VAL, to,
1156 new MostSpecificCheckContext(deferredAttrContext, rsWarner, actual));
1157 }
1158
1159 /**
1160 * Subclass of method check context class that implements most specific
1161 * method conversion. If the actual type under analysis is a deferred type
1162 * a full blown structural analysis is carried out.
1163 */
1164 class MostSpecificCheckContext extends MethodCheckContext {
1165
1166 Type actual;
1167
1168 public MostSpecificCheckContext(DeferredAttrContext deferredAttrContext, Warner rsWarner, Type actual) {
1169 super(true, deferredAttrContext, rsWarner);
1170 this.actual = actual;
1171 }
1172
1173 public boolean compatible(Type found, Type req, Warner warn) {
1174 if (unrelatedFunctionalInterfaces(found, req) &&
1175 (actual != null && actual.getTag() == DEFERRED)) {
1176 DeferredType dt = (DeferredType) actual;
1177 JCTree speculativeTree = dt.speculativeTree(deferredAttrContext);
1178 if (speculativeTree != deferredAttr.stuckTree) {
1179 return functionalInterfaceMostSpecific(found, req, speculativeTree);
1180 }
1181 }
1182 return compatibleBySubtyping(found, req);
1183 }
1184
1185 private boolean compatibleBySubtyping(Type found, Type req) {
1186 if (!strict && found.isPrimitive() != req.isPrimitive()) {
1187 found = found.isPrimitive() ? types.boxedClass(found).type : types.unboxedType(found);
1188 }
1189 return types.isSubtypeNoCapture(found, deferredAttrContext.inferenceContext.asUndetVar(req));
1190 }
1191
1192 /** Whether {@code t} and {@code s} are unrelated functional interface types. */
1193 private boolean unrelatedFunctionalInterfaces(Type t, Type s) {
1194 return types.isFunctionalInterface(t.tsym) &&
1195 types.isFunctionalInterface(s.tsym) &&
1196 unrelatedInterfaces(t, s);
1197 }
1198
1199 /** Whether {@code t} and {@code s} are unrelated interface types; recurs on intersections. **/
1200 private boolean unrelatedInterfaces(Type t, Type s) {
1201 if (t.isCompound()) {
1202 for (Type ti : types.interfaces(t)) {
1203 if (!unrelatedInterfaces(ti, s)) {
1204 return false;
1205 }
1206 }
1207 return true;
1208 } else if (s.isCompound()) {
1209 for (Type si : types.interfaces(s)) {
1210 if (!unrelatedInterfaces(t, si)) {
1211 return false;
1212 }
1213 }
1214 return true;
1215 } else {
1216 return types.asSuper(t, s.tsym) == null && types.asSuper(s, t.tsym) == null;
1217 }
1218 }
1219
1220 /** Parameters {@code t} and {@code s} are unrelated functional interface types. */
1221 private boolean functionalInterfaceMostSpecific(Type t, Type s, JCTree tree) {
1222 Type tDesc;
1223 Type tDescNoCapture;
1224 Type sDesc;
1225 try {
1226 tDesc = types.findDescriptorType(types.capture(t));
1227 tDescNoCapture = types.findDescriptorType(t);
1228 sDesc = types.findDescriptorType(s);
1229 } catch (Types.FunctionDescriptorLookupError ex) {
1230 // don't report, a more meaningful error should be reported upstream
1231 return false;
1232 }
1233 final List<Type> tTypeParams = tDesc.getTypeArguments();
1234 final List<Type> tTypeParamsNoCapture = tDescNoCapture.getTypeArguments();
1235 final List<Type> sTypeParams = sDesc.getTypeArguments();
1236
1237 // compare type parameters
1238 if (tDesc.hasTag(FORALL) && !types.hasSameBounds((ForAll) tDesc, (ForAll) tDescNoCapture)) {
1239 return false;
1240 }
1241 // can't use Types.hasSameBounds on sDesc because bounds may have ivars
1242 List<Type> tIter = tTypeParams;
1243 List<Type> sIter = sTypeParams;
1244 while (tIter.nonEmpty() && sIter.nonEmpty()) {
1245 Type tBound = tIter.head.getUpperBound();
1246 Type sBound = types.subst(sIter.head.getUpperBound(), sTypeParams, tTypeParams);
1247 if (tBound.containsAny(tTypeParams) && inferenceContext().free(sBound)) {
1248 return false;
1249 }
1250 if (!types.isSameType(tBound, inferenceContext().asUndetVar(sBound))) {
1251 return false;
1252 }
1253 tIter = tIter.tail;
1254 sIter = sIter.tail;
1255 }
1256 if (!tIter.isEmpty() || !sIter.isEmpty()) {
1257 return false;
1258 }
1259
1260 // compare parameters
1261 List<Type> tParams = tDesc.getParameterTypes();
1262 List<Type> tParamsNoCapture = tDescNoCapture.getParameterTypes();
1263 List<Type> sParams = sDesc.getParameterTypes();
1264 while (tParams.nonEmpty() && tParamsNoCapture.nonEmpty() && sParams.nonEmpty()) {
1265 Type tParam = tParams.head;
1266 Type tParamNoCapture = types.subst(tParamsNoCapture.head, tTypeParamsNoCapture, tTypeParams);
1267 Type sParam = types.subst(sParams.head, sTypeParams, tTypeParams);
1268 if (tParam.containsAny(tTypeParams) && inferenceContext().free(sParam)) {
1269 return false;
1270 }
1271 if (!types.isSubtype(inferenceContext().asUndetVar(sParam), tParam)) {
1272 return false;
1273 }
1274 if (!types.isSameType(tParamNoCapture, inferenceContext().asUndetVar(sParam))) {
1275 return false;
1276 }
1277 tParams = tParams.tail;
1278 tParamsNoCapture = tParamsNoCapture.tail;
1279 sParams = sParams.tail;
1280 }
1281 if (!tParams.isEmpty() || !tParamsNoCapture.isEmpty() || !sParams.isEmpty()) {
1282 return false;
1283 }
1284
1285 // compare returns
1286 Type tRet = tDesc.getReturnType();
1287 Type sRet = types.subst(sDesc.getReturnType(), sTypeParams, tTypeParams);
1288 if (tRet.containsAny(tTypeParams) && inferenceContext().free(sRet)) {
1289 return false;
1290 }
1291 MostSpecificFunctionReturnChecker msc = new MostSpecificFunctionReturnChecker(tRet, sRet);
1292 msc.scan(tree);
1293 return msc.result;
1294 }
1295
1296 /**
1297 * Tests whether one functional interface type can be considered more specific
1298 * than another unrelated functional interface type for the scanned expression.
1299 */
1300 class MostSpecificFunctionReturnChecker extends DeferredAttr.PolyScanner {
1301
1302 final Type tRet;
1303 final Type sRet;
1304 boolean result;
1305
1306 /** Parameters {@code t} and {@code s} are unrelated functional interface types. */
1307 MostSpecificFunctionReturnChecker(Type tRet, Type sRet) {
1308 this.tRet = tRet;
1309 this.sRet = sRet;
1310 result = true;
1311 }
1312
1313 @Override
1314 protected void skip(JCTree tree) {
1315 result = false;
1316 }
1317
1318 @Override
1319 public void visitConditional(JCConditional tree) {
1320 scan(asExpr(tree.truepart));
1321 scan(asExpr(tree.falsepart));
1322 }
1323
1324 @Override
1325 public void visitReference(JCMemberReference tree) {
1326 if (sRet.hasTag(VOID)) {
1327 // do nothing
1328 } else if (tRet.hasTag(VOID)) {
1329 result = false;
1330 } else if (tRet.isPrimitive() != sRet.isPrimitive()) {
1331 boolean retValIsPrimitive =
1332 tree.refPolyKind == PolyKind.STANDALONE &&
1333 tree.sym.type.getReturnType().isPrimitive();
1334 result &= (retValIsPrimitive == tRet.isPrimitive()) &&
1335 (retValIsPrimitive != sRet.isPrimitive());
1336 } else {
1337 result &= compatibleBySubtyping(tRet, sRet);
1338 }
1339 }
1340
1341 @Override
1342 public void visitParens(JCParens tree) {
1343 scan(asExpr(tree.expr));
1344 }
1345
1346 @Override
1347 public void visitLambda(JCLambda tree) {
1348 if (sRet.hasTag(VOID)) {
1349 // do nothing
1350 } else if (tRet.hasTag(VOID)) {
1351 result = false;
1352 } else {
1353 List<JCExpression> lambdaResults = lambdaResults(tree);
1354 if (!lambdaResults.isEmpty() && unrelatedFunctionalInterfaces(tRet, sRet)) {
1355 for (JCExpression expr : lambdaResults) {
1356 result &= functionalInterfaceMostSpecific(tRet, sRet, expr);
1357 }
1358 } else if (!lambdaResults.isEmpty() && tRet.isPrimitive() != sRet.isPrimitive()) {
1359 for (JCExpression expr : lambdaResults) {
1360 boolean retValIsPrimitive = expr.isStandalone() && expr.type.isPrimitive();
1361 result &= (retValIsPrimitive == tRet.isPrimitive()) &&
1362 (retValIsPrimitive != sRet.isPrimitive());
1363 }
1364 } else {
1365 result &= compatibleBySubtyping(tRet, sRet);
1366 }
1367 }
1368 }
1369 //where
1370
1371 private List<JCExpression> lambdaResults(JCLambda lambda) {
1372 if (lambda.getBodyKind() == JCTree.JCLambda.BodyKind.EXPRESSION) {
1373 return List.of(asExpr((JCExpression) lambda.body));
1374 } else {
1375 final ListBuffer<JCExpression> buffer = new ListBuffer<>();
1376 DeferredAttr.LambdaReturnScanner lambdaScanner =
1377 new DeferredAttr.LambdaReturnScanner() {
1378 @Override
1379 public void visitReturn(JCReturn tree) {
1380 if (tree.expr != null) {
1381 buffer.append(asExpr(tree.expr));
1382 }
1383 }
1384 };
1385 lambdaScanner.scan(lambda.body);
1386 return buffer.toList();
1387 }
1388 }
1389
1390 private JCExpression asExpr(JCExpression expr) {
1391 if (expr.type.hasTag(DEFERRED)) {
1392 JCTree speculativeTree = ((DeferredType)expr.type).speculativeTree(deferredAttrContext);
1393 if (speculativeTree != deferredAttr.stuckTree) {
1394 expr = (JCExpression)speculativeTree;
1395 }
1396 }
1397 return expr;
1398 }
1399 }
1400
1401 }
1402
1403 public MethodCheck mostSpecificCheck(List<Type> actuals) {
1404 Assert.error("Cannot get here!");
1405 return null;
1406 }
1407 }
1408
1409 public static class InapplicableMethodException extends CompilerInternalException {
1410 private static final long serialVersionUID = 0;
1411
1412 transient JCDiagnostic diagnostic;
1413
1414 InapplicableMethodException(JCDiagnostic diag, boolean dumpStackTraceOnError) {
1415 super(dumpStackTraceOnError);
1416 this.diagnostic = diag;
1417 }
1418
1419 public JCDiagnostic getDiagnostic() {
1420 return diagnostic;
1421 }
1422 }
1423
1424 /* ***************************************************************************
1425 * Symbol lookup
1426 * the following naming conventions for arguments are used
1427 *
1428 * env is the environment where the symbol was mentioned
1429 * site is the type of which the symbol is a member
1430 * name is the symbol's name
1431 * if no arguments are given
1432 * argtypes are the value arguments, if we search for a method
1433 *
1434 * If no symbol was found, a ResolveError detailing the problem is returned.
1435 ****************************************************************************/
1436
1437 /** Find field. Synthetic fields are always skipped.
1438 * @param env The current environment.
1439 * @param site The original type from where the selection takes place.
1440 * @param name The name of the field.
1441 * @param c The class to search for the field. This is always
1442 * a superclass or implemented interface of site's class.
1443 */
1444 Symbol findField(Env<AttrContext> env,
1445 Type site,
1446 Name name,
1447 TypeSymbol c) {
1448 while (c.type.hasTag(TYPEVAR))
1449 c = c.type.getUpperBound().tsym;
1450 Symbol bestSoFar = varNotFound;
1451 Symbol sym;
1452 for (Symbol s : c.members().getSymbolsByName(name)) {
1453 if (s.kind == VAR && (s.flags_field & SYNTHETIC) == 0) {
1454 return isAccessible(env, site, s)
1455 ? s : new AccessError(env, site, s);
1456 }
1457 }
1458 Type st = types.supertype(c.type);
1459 if (st != null && (st.hasTag(CLASS) || st.hasTag(TYPEVAR))) {
1460 sym = findField(env, site, name, st.tsym);
1461 bestSoFar = bestOf(bestSoFar, sym);
1462 }
1463 for (List<Type> l = types.interfaces(c.type);
1464 bestSoFar.kind != AMBIGUOUS && l.nonEmpty();
1465 l = l.tail) {
1466 sym = findField(env, site, name, l.head.tsym);
1467 if (bestSoFar.exists() && sym.exists() &&
1468 sym.owner != bestSoFar.owner)
1469 bestSoFar = new AmbiguityError(bestSoFar, sym);
1470 else
1471 bestSoFar = bestOf(bestSoFar, sym);
1472 }
1473 return bestSoFar;
1474 }
1475
1476 /** Resolve a field identifier, throw a fatal error if not found.
1477 * @param pos The position to use for error reporting.
1478 * @param env The environment current at the method invocation.
1479 * @param site The type of the qualifying expression, in which
1480 * identifier is searched.
1481 * @param name The identifier's name.
1482 */
1483 public VarSymbol resolveInternalField(DiagnosticPosition pos, Env<AttrContext> env,
1484 Type site, Name name) {
1485 Symbol sym = findField(env, site, name, site.tsym);
1486 if (sym.kind == VAR) return (VarSymbol)sym;
1487 else throw new FatalError(
1488 diags.fragment(Fragments.FatalErrCantLocateField(name)));
1489 }
1490
1491 /** Find unqualified variable or field with given name.
1492 * Synthetic fields always skipped.
1493 * @param pos The position to use for error reporting.
1494 * @param env The current environment.
1495 * @param name The name of the variable or field.
1496 */
1497 Symbol findVar(DiagnosticPosition pos, Env<AttrContext> env, Name name) {
1498 Symbol bestSoFar = varNotFound;
1499 Env<AttrContext> env1 = env;
1500 boolean staticOnly = false;
1501 while (env1.outer != null) {
1502 Symbol sym = null;
1503 for (Symbol s : env1.info.scope.getSymbolsByName(name)) {
1504 if (s.kind == VAR && (s.flags_field & SYNTHETIC) == 0) {
1505 sym = s;
1506 if (staticOnly) {
1507 return new StaticError(sym);
1508 }
1509 break;
1510 }
1511 }
1512 if (isStatic(env1)) staticOnly = true;
1513 if (sym == null) {
1514 sym = findField(env1, env1.enclClass.sym.type, name, env1.enclClass.sym);
1515 }
1516 if (sym.exists()) {
1517 if (sym.kind == VAR &&
1518 sym.owner.kind == TYP &&
1519 (sym.flags() & STATIC) == 0) {
1520 if (staticOnly)
1521 return new StaticError(sym);
1522 if (env1.info.ctorPrologue && !isAllowedEarlyReference(pos, env1, (VarSymbol)sym))
1523 return new RefBeforeCtorCalledError(sym);
1524 }
1525 return sym;
1526 } else {
1527 bestSoFar = bestOf(bestSoFar, sym);
1528 }
1529
1530 if ((env1.enclClass.sym.flags() & STATIC) != 0) staticOnly = true;
1531 env1 = env1.outer;
1532 }
1533
1534 Symbol sym = findField(env, syms.predefClass.type, name, syms.predefClass);
1535 if (sym.exists())
1536 return sym;
1537 if (bestSoFar.exists())
1538 return bestSoFar;
1539
1540 Symbol origin = null;
1541 for (Scope sc : new Scope[] { env.toplevel.namedImportScope, env.toplevel.starImportScope }) {
1542 for (Symbol currentSymbol : sc.getSymbolsByName(name)) {
1543 if (currentSymbol.kind != VAR)
1544 continue;
1545 // invariant: sym.kind == Symbol.Kind.VAR
1546 if (!bestSoFar.kind.isResolutionError() &&
1547 currentSymbol.owner != bestSoFar.owner)
1548 return new AmbiguityError(bestSoFar, currentSymbol);
1549 else if (!bestSoFar.kind.betterThan(VAR)) {
1550 origin = sc.getOrigin(currentSymbol).owner;
1551 bestSoFar = isAccessible(env, origin.type, currentSymbol)
1552 ? currentSymbol : new AccessError(env, origin.type, currentSymbol);
1553 }
1554 }
1555 if (bestSoFar.exists()) break;
1556 }
1557 if (bestSoFar.kind == VAR && bestSoFar.owner.type != origin.type)
1558 return bestSoFar.clone(origin);
1559 else
1560 return bestSoFar;
1561 }
1562
1563 Warner noteWarner = new Warner();
1564
1565 /** Select the best method for a call site among two choices.
1566 * @param env The current environment.
1567 * @param site The original type from where the
1568 * selection takes place.
1569 * @param argtypes The invocation's value arguments,
1570 * @param typeargtypes The invocation's type arguments,
1571 * @param sym Proposed new best match.
1572 * @param bestSoFar Previously found best match.
1573 * @param allowBoxing Allow boxing conversions of arguments.
1574 * @param useVarargs Box trailing arguments into an array for varargs.
1575 */
1576 @SuppressWarnings("fallthrough")
1577 Symbol selectBest(Env<AttrContext> env,
1578 Type site,
1579 List<Type> argtypes,
1580 List<Type> typeargtypes,
1581 Symbol sym,
1582 Symbol bestSoFar,
1583 boolean allowBoxing,
1584 boolean useVarargs) {
1585 if (sym.kind == ERR ||
1586 (site.tsym != sym.owner && !sym.isInheritedIn(site.tsym, types)) ||
1587 !notOverriddenIn(site, sym)) {
1588 return bestSoFar;
1589 } else if (useVarargs && (sym.flags() & VARARGS) == 0) {
1590 return bestSoFar.kind.isResolutionError() ?
1591 new BadVarargsMethod((ResolveError)bestSoFar.baseSymbol()) :
1592 bestSoFar;
1593 }
1594 Assert.check(!sym.kind.isResolutionError());
1595 try {
1596 types.noWarnings.clear();
1597 Type mt = rawInstantiate(env, site, sym, null, argtypes, typeargtypes,
1598 allowBoxing, useVarargs, types.noWarnings);
1599 currentResolutionContext.addApplicableCandidate(sym, mt);
1600 } catch (InapplicableMethodException ex) {
1601 currentResolutionContext.addInapplicableCandidate(sym, ex.getDiagnostic());
1602 // Currently, an InapplicableMethodException occurs.
1603 // If bestSoFar.kind was ABSENT_MTH, return an InapplicableSymbolError(kind is WRONG_MTH).
1604 // If bestSoFar.kind was HIDDEN(AccessError)/WRONG_MTH/WRONG_MTHS, return an InapplicableSymbolsError(kind is WRONG_MTHS).
1605 // See JDK-8255968 for more information.
1606 switch (bestSoFar.kind) {
1607 case ABSENT_MTH:
1608 return new InapplicableSymbolError(currentResolutionContext);
1609 case HIDDEN:
1610 if (bestSoFar instanceof AccessError accessError) {
1611 // Add the JCDiagnostic of previous AccessError to the currentResolutionContext
1612 // and construct InapplicableSymbolsError.
1613 // Intentionally fallthrough.
1614 currentResolutionContext.addInapplicableCandidate(accessError.sym,
1615 accessError.getDiagnostic(JCDiagnostic.DiagnosticType.FRAGMENT, null, null, site, null, argtypes, typeargtypes));
1616 } else {
1617 return bestSoFar;
1618 }
1619 case WRONG_MTH:
1620 bestSoFar = new InapplicableSymbolsError(currentResolutionContext);
1621 default:
1622 return bestSoFar;
1623 }
1624 }
1625 if (!isAccessible(env, site, sym)) {
1626 AccessError curAccessError = new AccessError(env, site, sym);
1627 JCDiagnostic curDiagnostic = curAccessError.getDiagnostic(JCDiagnostic.DiagnosticType.FRAGMENT, null, null, site, null, argtypes, typeargtypes);
1628 // Currently, an AccessError occurs.
1629 // If bestSoFar.kind was ABSENT_MTH, return an AccessError(kind is HIDDEN).
1630 // If bestSoFar.kind was HIDDEN(AccessError), WRONG_MTH, WRONG_MTHS, return an InapplicableSymbolsError(kind is WRONG_MTHS).
1631 // See JDK-8255968 for more information.
1632 if (bestSoFar.kind == ABSENT_MTH) {
1633 bestSoFar = curAccessError;
1634 } else if (bestSoFar.kind == WRONG_MTH) {
1635 // Add the JCDiagnostic of current AccessError to the currentResolutionContext
1636 // and construct InapplicableSymbolsError.
1637 currentResolutionContext.addInapplicableCandidate(sym, curDiagnostic);
1638 bestSoFar = new InapplicableSymbolsError(currentResolutionContext);
1639 } else if (bestSoFar.kind == WRONG_MTHS) {
1640 // Add the JCDiagnostic of current AccessError to the currentResolutionContext
1641 currentResolutionContext.addInapplicableCandidate(sym, curDiagnostic);
1642 } else if (bestSoFar.kind == HIDDEN && bestSoFar instanceof AccessError accessError) {
1643 // Add the JCDiagnostics of previous and current AccessError to the currentResolutionContext
1644 // and construct InapplicableSymbolsError.
1645 currentResolutionContext.addInapplicableCandidate(accessError.sym,
1646 accessError.getDiagnostic(JCDiagnostic.DiagnosticType.FRAGMENT, null, null, site, null, argtypes, typeargtypes));
1647 currentResolutionContext.addInapplicableCandidate(sym, curDiagnostic);
1648 bestSoFar = new InapplicableSymbolsError(currentResolutionContext);
1649 }
1650 return bestSoFar;
1651 }
1652 return (bestSoFar.kind.isResolutionError() && bestSoFar.kind != AMBIGUOUS)
1653 ? sym
1654 : mostSpecific(argtypes, sym, bestSoFar, env, site, useVarargs);
1655 }
1656
1657 /* Return the most specific of the two methods for a call,
1658 * given that both are accessible and applicable.
1659 * @param m1 A new candidate for most specific.
1660 * @param m2 The previous most specific candidate.
1661 * @param env The current environment.
1662 * @param site The original type from where the selection
1663 * takes place.
1664 * @param allowBoxing Allow boxing conversions of arguments.
1665 * @param useVarargs Box trailing arguments into an array for varargs.
1666 */
1667 Symbol mostSpecific(List<Type> argtypes, Symbol m1,
1668 Symbol m2,
1669 Env<AttrContext> env,
1670 final Type site,
1671 boolean useVarargs) {
1672 switch (m2.kind) {
1673 case MTH:
1674 if (m1 == m2) return m1;
1675 boolean m1SignatureMoreSpecific =
1676 signatureMoreSpecific(argtypes, env, site, m1, m2, useVarargs);
1677 boolean m2SignatureMoreSpecific =
1678 signatureMoreSpecific(argtypes, env, site, m2, m1, useVarargs);
1679 if (m1SignatureMoreSpecific && m2SignatureMoreSpecific) {
1680 Type mt1 = types.memberType(site, m1);
1681 Type mt2 = types.memberType(site, m2);
1682 if (!types.overrideEquivalent(mt1, mt2))
1683 return ambiguityError(m1, m2);
1684
1685 // same signature; select (a) the non-bridge method, or
1686 // (b) the one that overrides the other, or (c) the concrete
1687 // one, or (d) merge both abstract signatures
1688 if ((m1.flags() & BRIDGE) != (m2.flags() & BRIDGE))
1689 return ((m1.flags() & BRIDGE) != 0) ? m2 : m1;
1690
1691 if (m1.baseSymbol() == m2.baseSymbol()) {
1692 // this is the same imported symbol which has been cloned twice.
1693 // Return the first one (either will do).
1694 return m1;
1695 }
1696
1697 // if one overrides or hides the other, use it
1698 TypeSymbol m1Owner = (TypeSymbol)m1.owner;
1699 TypeSymbol m2Owner = (TypeSymbol)m2.owner;
1700 // the two owners can never be the same if the target methods are compiled from source,
1701 // but we need to protect against cases where the methods are defined in some classfile
1702 // and make sure we issue an ambiguity error accordingly (by skipping the logic below).
1703 if (m1Owner != m2Owner) {
1704 if (types.asSuper(m1Owner.type, m2Owner) != null &&
1705 ((m1.owner.flags_field & INTERFACE) == 0 ||
1706 (m2.owner.flags_field & INTERFACE) != 0) &&
1707 m1.overrides(m2, m1Owner, types, false))
1708 return m1;
1709 if (types.asSuper(m2Owner.type, m1Owner) != null &&
1710 ((m2.owner.flags_field & INTERFACE) == 0 ||
1711 (m1.owner.flags_field & INTERFACE) != 0) &&
1712 m2.overrides(m1, m2Owner, types, false))
1713 return m2;
1714 }
1715 boolean m1Abstract = (m1.flags() & ABSTRACT) != 0;
1716 boolean m2Abstract = (m2.flags() & ABSTRACT) != 0;
1717 if (m1Abstract && !m2Abstract) return m2;
1718 if (m2Abstract && !m1Abstract) return m1;
1719 // both abstract or both concrete
1720 return ambiguityError(m1, m2);
1721 }
1722 if (m1SignatureMoreSpecific) return m1;
1723 if (m2SignatureMoreSpecific) return m2;
1724 return ambiguityError(m1, m2);
1725 case AMBIGUOUS:
1726 //compare m1 to ambiguous methods in m2
1727 AmbiguityError e = (AmbiguityError)m2.baseSymbol();
1728 boolean m1MoreSpecificThanAnyAmbiguous = true;
1729 boolean allAmbiguousMoreSpecificThanM1 = true;
1730 for (Symbol s : e.ambiguousSyms) {
1731 Symbol moreSpecific = mostSpecific(argtypes, m1, s, env, site, useVarargs);
1732 m1MoreSpecificThanAnyAmbiguous &= moreSpecific == m1;
1733 allAmbiguousMoreSpecificThanM1 &= moreSpecific == s;
1734 }
1735 if (m1MoreSpecificThanAnyAmbiguous)
1736 return m1;
1737 //if m1 is more specific than some ambiguous methods, but other ambiguous methods are
1738 //more specific than m1, add it as a new ambiguous method:
1739 if (!allAmbiguousMoreSpecificThanM1)
1740 e.addAmbiguousSymbol(m1);
1741 return e;
1742 default:
1743 throw new AssertionError();
1744 }
1745 }
1746 //where
1747 private boolean signatureMoreSpecific(List<Type> actuals, Env<AttrContext> env, Type site, Symbol m1, Symbol m2, boolean useVarargs) {
1748 noteWarner.clear();
1749 int maxLength = Math.max(
1750 Math.max(m1.type.getParameterTypes().length(), actuals.length()),
1751 m2.type.getParameterTypes().length());
1752 MethodResolutionContext prevResolutionContext = currentResolutionContext;
1753 try {
1754 currentResolutionContext = new MethodResolutionContext();
1755 currentResolutionContext.step = prevResolutionContext.step;
1756 currentResolutionContext.methodCheck =
1757 prevResolutionContext.methodCheck.mostSpecificCheck(actuals);
1758 Type mst = instantiate(env, site, m2, null,
1759 adjustArgs(types.cvarLowerBounds(types.memberType(site, m1).getParameterTypes()), m1, maxLength, useVarargs), null,
1760 false, useVarargs, noteWarner);
1761 return mst != null &&
1762 !noteWarner.hasLint(Lint.LintCategory.UNCHECKED);
1763 } finally {
1764 currentResolutionContext = prevResolutionContext;
1765 }
1766 }
1767
1768 List<Type> adjustArgs(List<Type> args, Symbol msym, int length, boolean allowVarargs) {
1769 if ((msym.flags() & VARARGS) != 0 && allowVarargs) {
1770 Type varargsElem = types.elemtype(args.last());
1771 if (varargsElem == null) {
1772 Assert.error("Bad varargs = " + args.last() + " " + msym);
1773 }
1774 List<Type> newArgs = args.reverse().tail.prepend(varargsElem).reverse();
1775 while (newArgs.length() < length) {
1776 newArgs = newArgs.append(newArgs.last());
1777 }
1778 return newArgs;
1779 } else {
1780 return args;
1781 }
1782 }
1783 //where
1784 Symbol ambiguityError(Symbol m1, Symbol m2) {
1785 if (((m1.flags() | m2.flags()) & CLASH) != 0) {
1786 return (m1.flags() & CLASH) == 0 ? m1 : m2;
1787 } else {
1788 return new AmbiguityError(m1, m2);
1789 }
1790 }
1791
1792 Symbol findMethodInScope(Env<AttrContext> env,
1793 Type site,
1794 Name name,
1795 List<Type> argtypes,
1796 List<Type> typeargtypes,
1797 Scope sc,
1798 Symbol bestSoFar,
1799 boolean allowBoxing,
1800 boolean useVarargs,
1801 boolean abstractok) {
1802 for (Symbol s : sc.getSymbolsByName(name, new LookupFilter(abstractok))) {
1803 bestSoFar = selectBest(env, site, argtypes, typeargtypes, s,
1804 bestSoFar, allowBoxing, useVarargs);
1805 }
1806 return bestSoFar;
1807 }
1808 //where
1809 class LookupFilter implements Predicate<Symbol> {
1810
1811 boolean abstractOk;
1812
1813 LookupFilter(boolean abstractOk) {
1814 this.abstractOk = abstractOk;
1815 }
1816
1817 @Override
1818 public boolean test(Symbol s) {
1819 long flags = s.flags();
1820 return s.kind == MTH &&
1821 (flags & SYNTHETIC) == 0 &&
1822 (abstractOk ||
1823 (flags & DEFAULT) != 0 ||
1824 (flags & ABSTRACT) == 0);
1825 }
1826 }
1827
1828 /** Find best qualified method matching given name, type and value
1829 * arguments.
1830 * @param env The current environment.
1831 * @param site The original type from where the selection
1832 * takes place.
1833 * @param name The method's name.
1834 * @param argtypes The method's value arguments.
1835 * @param typeargtypes The method's type arguments
1836 * @param allowBoxing Allow boxing conversions of arguments.
1837 * @param useVarargs Box trailing arguments into an array for varargs.
1838 */
1839 Symbol findMethod(Env<AttrContext> env,
1840 Type site,
1841 Name name,
1842 List<Type> argtypes,
1843 List<Type> typeargtypes,
1844 boolean allowBoxing,
1845 boolean useVarargs) {
1846 Symbol bestSoFar = methodNotFound;
1847 bestSoFar = findMethod(env,
1848 site,
1849 name,
1850 argtypes,
1851 typeargtypes,
1852 site.tsym.type,
1853 bestSoFar,
1854 allowBoxing,
1855 useVarargs);
1856 return bestSoFar;
1857 }
1858 // where
1859 private Symbol findMethod(Env<AttrContext> env,
1860 Type site,
1861 Name name,
1862 List<Type> argtypes,
1863 List<Type> typeargtypes,
1864 Type intype,
1865 Symbol bestSoFar,
1866 boolean allowBoxing,
1867 boolean useVarargs) {
1868 @SuppressWarnings({"unchecked","rawtypes"})
1869 List<Type>[] itypes = (List<Type>[])new List[] { List.<Type>nil(), List.<Type>nil() };
1870
1871 InterfaceLookupPhase iphase = InterfaceLookupPhase.ABSTRACT_OK;
1872 boolean isInterface = site.tsym.isInterface();
1873 for (TypeSymbol s : isInterface ? List.of(intype.tsym) : superclasses(intype)) {
1874 bestSoFar = findMethodInScope(env, site, name, argtypes, typeargtypes,
1875 s.members(), bestSoFar, allowBoxing, useVarargs, true);
1876 if (name == names.init) return bestSoFar;
1877 iphase = (iphase == null) ? null : iphase.update(s, this);
1878 if (iphase != null) {
1879 for (Type itype : types.interfaces(s.type)) {
1880 itypes[iphase.ordinal()] = types.union(types.closure(itype), itypes[iphase.ordinal()]);
1881 }
1882 }
1883 }
1884
1885 Symbol concrete = bestSoFar.kind.isValid() &&
1886 (bestSoFar.flags() & ABSTRACT) == 0 ?
1887 bestSoFar : methodNotFound;
1888
1889 for (InterfaceLookupPhase iphase2 : InterfaceLookupPhase.values()) {
1890 //keep searching for abstract methods
1891 for (Type itype : itypes[iphase2.ordinal()]) {
1892 if (!itype.isInterface()) continue; //skip j.l.Object (included by Types.closure())
1893 if (iphase2 == InterfaceLookupPhase.DEFAULT_OK &&
1894 (itype.tsym.flags() & DEFAULT) == 0) continue;
1895 bestSoFar = findMethodInScope(env, site, name, argtypes, typeargtypes,
1896 itype.tsym.members(), bestSoFar, allowBoxing, useVarargs, true);
1897 if (concrete != bestSoFar &&
1898 concrete.kind.isValid() &&
1899 bestSoFar.kind.isValid() &&
1900 types.isSubSignature(concrete.type, bestSoFar.type)) {
1901 //this is an hack - as javac does not do full membership checks
1902 //most specific ends up comparing abstract methods that might have
1903 //been implemented by some concrete method in a subclass and,
1904 //because of raw override, it is possible for an abstract method
1905 //to be more specific than the concrete method - so we need
1906 //to explicitly call that out (see CR 6178365)
1907 bestSoFar = concrete;
1908 }
1909 }
1910 }
1911 if (isInterface && bestSoFar.kind.isResolutionError()) {
1912 bestSoFar = findMethodInScope(env, site, name, argtypes, typeargtypes,
1913 syms.objectType.tsym.members(), bestSoFar, allowBoxing, useVarargs, true);
1914 if (bestSoFar.kind.isValid()) {
1915 Symbol baseSymbol = bestSoFar;
1916 bestSoFar = new MethodSymbol(bestSoFar.flags_field, bestSoFar.name, bestSoFar.type, intype.tsym) {
1917 @Override
1918 public Symbol baseSymbol() {
1919 return baseSymbol;
1920 }
1921 };
1922 }
1923 }
1924 return bestSoFar;
1925 }
1926
1927 enum InterfaceLookupPhase {
1928 ABSTRACT_OK() {
1929 @Override
1930 InterfaceLookupPhase update(Symbol s, Resolve rs) {
1931 //We should not look for abstract methods if receiver is a concrete class
1932 //(as concrete classes are expected to implement all abstracts coming
1933 //from superinterfaces)
1934 if ((s.flags() & (ABSTRACT | INTERFACE | ENUM)) != 0) {
1935 return this;
1936 } else {
1937 return DEFAULT_OK;
1938 }
1939 }
1940 },
1941 DEFAULT_OK() {
1942 @Override
1943 InterfaceLookupPhase update(Symbol s, Resolve rs) {
1944 return this;
1945 }
1946 };
1947
1948 abstract InterfaceLookupPhase update(Symbol s, Resolve rs);
1949 }
1950
1951 /**
1952 * Return an Iterable object to scan the superclasses of a given type.
1953 * It's crucial that the scan is done lazily, as we don't want to accidentally
1954 * access more supertypes than strictly needed (as this could trigger completion
1955 * errors if some of the not-needed supertypes are missing/ill-formed).
1956 */
1957 Iterable<TypeSymbol> superclasses(final Type intype) {
1958 return () -> new Iterator<TypeSymbol>() {
1959
1960 List<TypeSymbol> seen = List.nil();
1961 TypeSymbol currentSym = symbolFor(intype);
1962 TypeSymbol prevSym = null;
1963
1964 public boolean hasNext() {
1965 if (currentSym == syms.noSymbol) {
1966 currentSym = symbolFor(types.supertype(prevSym.type));
1967 }
1968 return currentSym != null;
1969 }
1970
1971 public TypeSymbol next() {
1972 prevSym = currentSym;
1973 currentSym = syms.noSymbol;
1974 Assert.check(prevSym != null || prevSym != syms.noSymbol);
1975 return prevSym;
1976 }
1977
1978 public void remove() {
1979 throw new UnsupportedOperationException();
1980 }
1981
1982 TypeSymbol symbolFor(Type t) {
1983 if (!t.hasTag(CLASS) &&
1984 !t.hasTag(TYPEVAR)) {
1985 return null;
1986 }
1987 t = types.skipTypeVars(t, false);
1988 if (seen.contains(t.tsym)) {
1989 //degenerate case in which we have a circular
1990 //class hierarchy - because of ill-formed classfiles
1991 return null;
1992 }
1993 seen = seen.prepend(t.tsym);
1994 return t.tsym;
1995 }
1996 };
1997 }
1998
1999 /** Find unqualified method matching given name, type and value arguments.
2000 * @param env The current environment.
2001 * @param name The method's name.
2002 * @param argtypes The method's value arguments.
2003 * @param typeargtypes The method's type arguments.
2004 * @param allowBoxing Allow boxing conversions of arguments.
2005 * @param useVarargs Box trailing arguments into an array for varargs.
2006 */
2007 Symbol findFun(Env<AttrContext> env, Name name,
2008 List<Type> argtypes, List<Type> typeargtypes,
2009 boolean allowBoxing, boolean useVarargs) {
2010 Symbol bestSoFar = methodNotFound;
2011 Env<AttrContext> env1 = env;
2012 boolean staticOnly = false;
2013 while (env1.outer != null) {
2014 if (isStatic(env1)) staticOnly = true;
2015 Assert.check(env1.info.preferredTreeForDiagnostics == null);
2016 env1.info.preferredTreeForDiagnostics = env.tree;
2017 try {
2018 Symbol sym = findMethod(
2019 env1, env1.enclClass.sym.type, name, argtypes, typeargtypes,
2020 allowBoxing, useVarargs);
2021 if (sym.exists()) {
2022 if (sym.kind == MTH &&
2023 sym.owner.kind == TYP &&
2024 (sym.flags() & STATIC) == 0) {
2025 if (staticOnly)
2026 return new StaticError(sym);
2027 if (env1.info.ctorPrologue && env1 == env)
2028 return new RefBeforeCtorCalledError(sym);
2029 }
2030 return sym;
2031 } else {
2032 bestSoFar = bestOf(bestSoFar, sym);
2033 }
2034 } finally {
2035 env1.info.preferredTreeForDiagnostics = null;
2036 }
2037 if ((env1.enclClass.sym.flags() & STATIC) != 0) staticOnly = true;
2038 env1 = env1.outer;
2039 }
2040
2041 Symbol sym = findMethod(env, syms.predefClass.type, name, argtypes,
2042 typeargtypes, allowBoxing, useVarargs);
2043 if (sym.exists())
2044 return sym;
2045
2046 for (Symbol currentSym : env.toplevel.namedImportScope.getSymbolsByName(name)) {
2047 Symbol origin = env.toplevel.namedImportScope.getOrigin(currentSym).owner;
2048 if (currentSym.kind == MTH) {
2049 if (currentSym.owner.type != origin.type)
2050 currentSym = currentSym.clone(origin);
2051 if (!isAccessible(env, origin.type, currentSym))
2052 currentSym = new AccessError(env, origin.type, currentSym);
2053 bestSoFar = selectBest(env, origin.type,
2054 argtypes, typeargtypes,
2055 currentSym, bestSoFar,
2056 allowBoxing, useVarargs);
2057 }
2058 }
2059 if (bestSoFar.exists())
2060 return bestSoFar;
2061
2062 for (Symbol currentSym : env.toplevel.starImportScope.getSymbolsByName(name)) {
2063 Symbol origin = env.toplevel.starImportScope.getOrigin(currentSym).owner;
2064 if (currentSym.kind == MTH) {
2065 if (currentSym.owner.type != origin.type)
2066 currentSym = currentSym.clone(origin);
2067 if (!isAccessible(env, origin.type, currentSym))
2068 currentSym = new AccessError(env, origin.type, currentSym);
2069 bestSoFar = selectBest(env, origin.type,
2070 argtypes, typeargtypes,
2071 currentSym, bestSoFar,
2072 allowBoxing, useVarargs);
2073 }
2074 }
2075 return bestSoFar;
2076 }
2077
2078 /** Load toplevel or member class with given fully qualified name and
2079 * verify that it is accessible.
2080 * @param env The current environment.
2081 * @param name The fully qualified name of the class to be loaded.
2082 */
2083 Symbol loadClass(Env<AttrContext> env, Name name, RecoveryLoadClass recoveryLoadClass) {
2084 try {
2085 ClassSymbol c = finder.loadClass(env.toplevel.modle, name);
2086 return isAccessible(env, c) ? c : new AccessError(env, null, c);
2087 } catch (ClassFinder.BadClassFile err) {
2088 return new BadClassFileError(err);
2089 } catch (CompletionFailure ex) {
2090 Symbol candidate = recoveryLoadClass.loadClass(env, name);
2091
2092 if (candidate != null) {
2093 return candidate;
2094 }
2095
2096 return typeNotFound;
2097 }
2098 }
2099
2100 public interface RecoveryLoadClass {
2101 Symbol loadClass(Env<AttrContext> env, Name name);
2102 }
2103
2104 private final RecoveryLoadClass noRecovery = (env, name) -> null;
2105
2106 private final RecoveryLoadClass doRecoveryLoadClass = new RecoveryLoadClass() {
2107 @Override public Symbol loadClass(Env<AttrContext> env, Name name) {
2108 List<Name> candidates = Convert.classCandidates(name);
2109 return lookupInvisibleSymbol(env, name,
2110 n -> () -> createCompoundIterator(candidates,
2111 c -> syms.getClassesForName(c)
2112 .iterator()),
2113 (ms, n) -> {
2114 for (Name candidate : candidates) {
2115 try {
2116 return finder.loadClass(ms, candidate);
2117 } catch (CompletionFailure cf) {
2118 //ignore
2119 }
2120 }
2121 return null;
2122 }, sym -> sym.kind == Kind.TYP, typeNotFound);
2123 }
2124 };
2125
2126 private final RecoveryLoadClass namedImportScopeRecovery = (env, name) -> {
2127 Scope importScope = env.toplevel.namedImportScope;
2128 Symbol existing = importScope.findFirst(Convert.shortName(name),
2129 sym -> sym.kind == TYP && sym.flatName() == name);
2130
2131 if (existing != null) {
2132 return new InvisibleSymbolError(env, true, existing);
2133 }
2134 return null;
2135 };
2136
2137 private final RecoveryLoadClass starImportScopeRecovery = (env, name) -> {
2138 Scope importScope = env.toplevel.starImportScope;
2139 Symbol existing = importScope.findFirst(Convert.shortName(name),
2140 sym -> sym.kind == TYP && sym.flatName() == name);
2141
2142 if (existing != null) {
2143 try {
2144 existing = finder.loadClass(existing.packge().modle, name);
2145
2146 return new InvisibleSymbolError(env, true, existing);
2147 } catch (CompletionFailure cf) {
2148 //ignore
2149 }
2150 }
2151
2152 return null;
2153 };
2154
2155 Symbol lookupPackage(Env<AttrContext> env, Name name) {
2156 PackageSymbol pack = syms.lookupPackage(env.toplevel.modle, name);
2157
2158 if (allowModules && isImportOnDemand(env, name)) {
2159 if (pack.members().isEmpty()) {
2160 return lookupInvisibleSymbol(env, name, syms::getPackagesForName, syms::enterPackage, sym -> {
2161 sym.complete();
2162 return !sym.members().isEmpty();
2163 }, pack);
2164 }
2165 }
2166
2167 return pack;
2168 }
2169
2170 private boolean isImportOnDemand(Env<AttrContext> env, Name name) {
2171 if (!env.tree.hasTag(IMPORT))
2172 return false;
2173
2174 JCTree qualid = ((JCImport) env.tree).qualid;
2175
2176 if (!qualid.hasTag(SELECT))
2177 return false;
2178
2179 if (TreeInfo.name(qualid) != names.asterisk)
2180 return false;
2181
2182 return TreeInfo.fullName(((JCFieldAccess) qualid).selected) == name;
2183 }
2184
2185 private <S extends Symbol> Symbol lookupInvisibleSymbol(Env<AttrContext> env,
2186 Name name,
2187 Function<Name, Iterable<S>> get,
2188 BiFunction<ModuleSymbol, Name, S> load,
2189 Predicate<S> validate,
2190 Symbol defaultResult) {
2191 //even if a class/package cannot be found in the current module and among packages in modules
2192 //it depends on that are exported for any or this module, the class/package may exist internally
2193 //in some of these modules, or may exist in a module on which this module does not depend.
2194 //Provide better diagnostic in such cases by looking for the class in any module:
2195 Iterable<? extends S> candidates = get.apply(name);
2196
2197 for (S sym : candidates) {
2198 if (validate.test(sym))
2199 return createInvisibleSymbolError(env, sym);
2200 }
2201
2202 Set<ModuleSymbol> recoverableModules = new HashSet<>(syms.getAllModules());
2203
2204 recoverableModules.add(syms.unnamedModule);
2205 recoverableModules.remove(env.toplevel.modle);
2206
2207 for (ModuleSymbol ms : recoverableModules) {
2208 //avoid overly eager completing classes from source-based modules, as those
2209 //may not be completable with the current compiler settings:
2210 if (ms.sourceLocation == null) {
2211 if (ms.classLocation == null) {
2212 ms = moduleFinder.findModule(ms);
2213 }
2214
2215 if (ms.kind != ERR) {
2216 S sym = load.apply(ms, name);
2217
2218 if (sym != null && validate.test(sym)) {
2219 return createInvisibleSymbolError(env, sym);
2220 }
2221 }
2222 }
2223 }
2224
2225 return defaultResult;
2226 }
2227
2228 private Symbol createInvisibleSymbolError(Env<AttrContext> env, Symbol sym) {
2229 if (symbolPackageVisible(env, sym)) {
2230 return new AccessError(env, null, sym);
2231 } else {
2232 return new InvisibleSymbolError(env, false, sym);
2233 }
2234 }
2235
2236 private boolean symbolPackageVisible(Env<AttrContext> env, Symbol sym) {
2237 ModuleSymbol envMod = env.toplevel.modle;
2238 PackageSymbol symPack = sym.packge();
2239 return envMod == symPack.modle ||
2240 envMod.visiblePackages.containsKey(symPack.fullname);
2241 }
2242
2243 /**
2244 * Find a type declared in a scope (not inherited). Return null
2245 * if none is found.
2246 * @param env The current environment.
2247 * @param site The original type from where the selection takes
2248 * place.
2249 * @param name The type's name.
2250 * @param c The class to search for the member type. This is
2251 * always a superclass or implemented interface of
2252 * site's class.
2253 */
2254 Symbol findImmediateMemberType(Env<AttrContext> env,
2255 Type site,
2256 Name name,
2257 TypeSymbol c) {
2258 for (Symbol sym : c.members().getSymbolsByName(name)) {
2259 if (sym.kind == TYP) {
2260 return isAccessible(env, site, sym)
2261 ? sym
2262 : new AccessError(env, site, sym);
2263 }
2264 }
2265 return typeNotFound;
2266 }
2267
2268 /** Find a member type inherited from a superclass or interface.
2269 * @param env The current environment.
2270 * @param site The original type from where the selection takes
2271 * place.
2272 * @param name The type's name.
2273 * @param c The class to search for the member type. This is
2274 * always a superclass or implemented interface of
2275 * site's class.
2276 */
2277 Symbol findInheritedMemberType(Env<AttrContext> env,
2278 Type site,
2279 Name name,
2280 TypeSymbol c) {
2281 Symbol bestSoFar = typeNotFound;
2282 Symbol sym;
2283 Type st = types.supertype(c.type);
2284 if (st != null && st.hasTag(CLASS)) {
2285 sym = findMemberType(env, site, name, st.tsym);
2286 bestSoFar = bestOf(bestSoFar, sym);
2287 }
2288 for (List<Type> l = types.interfaces(c.type);
2289 bestSoFar.kind != AMBIGUOUS && l.nonEmpty();
2290 l = l.tail) {
2291 sym = findMemberType(env, site, name, l.head.tsym);
2292 if (!bestSoFar.kind.isResolutionError() &&
2293 !sym.kind.isResolutionError() &&
2294 sym.owner != bestSoFar.owner)
2295 bestSoFar = new AmbiguityError(bestSoFar, sym);
2296 else
2297 bestSoFar = bestOf(bestSoFar, sym);
2298 }
2299 return bestSoFar;
2300 }
2301
2302 /** Find qualified member type.
2303 * @param env The current environment.
2304 * @param site The original type from where the selection takes
2305 * place.
2306 * @param name The type's name.
2307 * @param c The class to search for the member type. This is
2308 * always a superclass or implemented interface of
2309 * site's class.
2310 */
2311 Symbol findMemberType(Env<AttrContext> env,
2312 Type site,
2313 Name name,
2314 TypeSymbol c) {
2315 Symbol sym = findImmediateMemberType(env, site, name, c);
2316
2317 if (sym != typeNotFound)
2318 return sym;
2319
2320 return findInheritedMemberType(env, site, name, c);
2321
2322 }
2323
2324 /** Find a global type in given scope and load corresponding class.
2325 * @param env The current environment.
2326 * @param scope The scope in which to look for the type.
2327 * @param name The type's name.
2328 */
2329 Symbol findGlobalType(Env<AttrContext> env, Scope scope, Name name, RecoveryLoadClass recoveryLoadClass) {
2330 Symbol bestSoFar = typeNotFound;
2331 for (Symbol s : scope.getSymbolsByName(name)) {
2332 Symbol sym = loadClass(env, s.flatName(), recoveryLoadClass);
2333 if (bestSoFar.kind == TYP && sym.kind == TYP &&
2334 bestSoFar != sym)
2335 return new AmbiguityError(bestSoFar, sym);
2336 else
2337 bestSoFar = bestOf(bestSoFar, sym);
2338 }
2339 return bestSoFar;
2340 }
2341
2342 Symbol findTypeVar(Env<AttrContext> env, Name name, boolean staticOnly) {
2343 for (Symbol sym : env.info.scope.getSymbolsByName(name)) {
2344 if (sym.kind == TYP) {
2345 if (sym.type.hasTag(TYPEVAR) &&
2346 (staticOnly || (isStatic(env) && sym.owner.kind == TYP)))
2347 // if staticOnly is set, it means that we have recursed through a static declaration,
2348 // so type variable symbols should not be accessible. If staticOnly is unset, but
2349 // we are in a static declaration (field or method), we should not allow type-variables
2350 // defined in the enclosing class to "leak" into this context.
2351 return new StaticError(sym);
2352 return sym;
2353 }
2354 }
2355 return typeNotFound;
2356 }
2357
2358 /** Find an unqualified type symbol.
2359 * @param env The current environment.
2360 * @param name The type's name.
2361 */
2362 Symbol findType(Env<AttrContext> env, Name name) {
2363 if (name == names.empty)
2364 return typeNotFound; // do not allow inadvertent "lookup" of anonymous types
2365 Symbol bestSoFar = typeNotFound;
2366 Symbol sym;
2367 boolean staticOnly = false;
2368 for (Env<AttrContext> env1 = env; env1.outer != null; env1 = env1.outer) {
2369 // First, look for a type variable and the first member type
2370 final Symbol tyvar = findTypeVar(env1, name, staticOnly);
2371 if (isStatic(env1)) staticOnly = true;
2372 sym = findImmediateMemberType(env1, env1.enclClass.sym.type,
2373 name, env1.enclClass.sym);
2374
2375 // Return the type variable if we have it, and have no
2376 // immediate member, OR the type variable is for a method.
2377 if (tyvar != typeNotFound) {
2378 if (env.baseClause || sym == typeNotFound ||
2379 (tyvar.kind == TYP && tyvar.exists() &&
2380 tyvar.owner.kind == MTH)) {
2381 return tyvar;
2382 }
2383 }
2384
2385 // If the environment is a class def, finish up,
2386 // otherwise, do the entire findMemberType
2387 if (sym == typeNotFound)
2388 sym = findInheritedMemberType(env1, env1.enclClass.sym.type,
2389 name, env1.enclClass.sym);
2390
2391 if (staticOnly && sym.kind == TYP &&
2392 sym.type.hasTag(CLASS) &&
2393 sym.type.getEnclosingType().hasTag(CLASS) &&
2394 env1.enclClass.sym.type.isParameterized() &&
2395 sym.type.getEnclosingType().isParameterized())
2396 return new StaticError(sym);
2397 else if (sym.exists()) return sym;
2398 else bestSoFar = bestOf(bestSoFar, sym);
2399
2400 JCClassDecl encl = env1.baseClause ? (JCClassDecl)env1.tree : env1.enclClass;
2401 if ((encl.sym.flags() & STATIC) != 0)
2402 staticOnly = true;
2403 }
2404
2405 if (!env.tree.hasTag(IMPORT)) {
2406 sym = findGlobalType(env, env.toplevel.namedImportScope, name, namedImportScopeRecovery);
2407 if (sym.exists()) return sym;
2408 else bestSoFar = bestOf(bestSoFar, sym);
2409
2410 sym = findGlobalType(env, env.toplevel.toplevelScope, name, noRecovery);
2411 if (sym.exists()) return sym;
2412 else bestSoFar = bestOf(bestSoFar, sym);
2413
2414 sym = findGlobalType(env, env.toplevel.packge.members(), name, noRecovery);
2415 if (sym.exists()) return sym;
2416 else bestSoFar = bestOf(bestSoFar, sym);
2417
2418 sym = findGlobalType(env, env.toplevel.starImportScope, name, starImportScopeRecovery);
2419 if (sym.exists()) return sym;
2420 else bestSoFar = bestOf(bestSoFar, sym);
2421 }
2422
2423 return bestSoFar;
2424 }
2425
2426 /** Find an unqualified identifier which matches a specified kind set.
2427 * @param pos position on which report warnings, if any;
2428 * null warnings should not be reported
2429 * @param env The current environment.
2430 * @param name The identifier's name.
2431 * @param kind Indicates the possible symbol kinds
2432 * (a subset of VAL, TYP, PCK).
2433 */
2434 Symbol findIdent(DiagnosticPosition pos, Env<AttrContext> env, Name name, KindSelector kind) {
2435 try {
2436 return checkNonExistentType(checkRestrictedType(pos, findIdentInternal(pos, env, name, kind), name));
2437 } catch (ClassFinder.BadClassFile err) {
2438 return new BadClassFileError(err);
2439 } catch (CompletionFailure cf) {
2440 chk.completionError(pos, cf);
2441 return typeNotFound;
2442 }
2443 }
2444
2445 Symbol findIdentInternal(DiagnosticPosition pos, Env<AttrContext> env, Name name, KindSelector kind) {
2446 Symbol bestSoFar = typeNotFound;
2447 Symbol sym;
2448
2449 if (kind.contains(KindSelector.VAL)) {
2450 sym = findVar(pos, env, name);
2451 if (sym.exists()) return sym;
2452 else bestSoFar = bestOf(bestSoFar, sym);
2453 }
2454
2455 if (kind.contains(KindSelector.TYP)) {
2456 sym = findType(env, name);
2457 if (sym.exists()) return sym;
2458 else bestSoFar = bestOf(bestSoFar, sym);
2459 }
2460
2461 if (kind.contains(KindSelector.PCK))
2462 return lookupPackage(env, name);
2463 else return bestSoFar;
2464 }
2465
2466 /** Find an identifier in a package which matches a specified kind set.
2467 * @param pos position on which report warnings, if any;
2468 * null warnings should not be reported
2469 * @param env The current environment.
2470 * @param name The identifier's name.
2471 * @param kind Indicates the possible symbol kinds
2472 * (a nonempty subset of TYP, PCK).
2473 */
2474 Symbol findIdentInPackage(DiagnosticPosition pos,
2475 Env<AttrContext> env, TypeSymbol pck,
2476 Name name, KindSelector kind) {
2477 return checkNonExistentType(checkRestrictedType(pos, findIdentInPackageInternal(env, pck, name, kind), name));
2478 }
2479
2480 Symbol findIdentInPackageInternal(Env<AttrContext> env, TypeSymbol pck,
2481 Name name, KindSelector kind) {
2482 Name fullname = TypeSymbol.formFullName(name, pck);
2483 Symbol bestSoFar = typeNotFound;
2484 if (kind.contains(KindSelector.TYP)) {
2485 RecoveryLoadClass recoveryLoadClass =
2486 allowModules && !kind.contains(KindSelector.PCK) &&
2487 !pck.exists() && !env.info.attributionMode.isSpeculative ?
2488 doRecoveryLoadClass : noRecovery;
2489 Symbol sym = loadClass(env, fullname, recoveryLoadClass);
2490 if (sym.exists()) {
2491 // don't allow programs to use flatnames
2492 if (name == sym.name) return sym;
2493 }
2494 else bestSoFar = bestOf(bestSoFar, sym);
2495 }
2496 if (kind.contains(KindSelector.PCK)) {
2497 return lookupPackage(env, fullname);
2498 }
2499 return bestSoFar;
2500 }
2501
2502 /** Find an identifier among the members of a given type `site'.
2503 * @param pos position on which report warnings, if any;
2504 * null warnings should not be reported
2505 * @param env The current environment.
2506 * @param site The type containing the symbol to be found.
2507 * @param name The identifier's name.
2508 * @param kind Indicates the possible symbol kinds
2509 * (a subset of VAL, TYP).
2510 */
2511 Symbol findIdentInType(DiagnosticPosition pos,
2512 Env<AttrContext> env, Type site,
2513 Name name, KindSelector kind) {
2514 try {
2515 return checkNonExistentType(checkRestrictedType(pos, findIdentInTypeInternal(env, site, name, kind), name));
2516 } catch (ClassFinder.BadClassFile err) {
2517 return new BadClassFileError(err);
2518 } catch (CompletionFailure cf) {
2519 chk.completionError(pos, cf);
2520 return typeNotFound;
2521 }
2522 }
2523
2524 private Symbol checkNonExistentType(Symbol symbol) {
2525 /* Guard against returning a type is not on the class path of the current compilation,
2526 * but *was* on the class path of a separate compilation that produced a class file
2527 * that is on the class path of the current compilation. Such a type will fail completion
2528 * but the completion failure may have been silently swallowed (e.g. missing annotation types)
2529 * with an error stub symbol lingering in the symbol tables.
2530 */
2531 return symbol instanceof ClassSymbol c && c.type.isErroneous() && c.classfile == null ? typeNotFound : symbol;
2532 }
2533
2534 Symbol findIdentInTypeInternal(Env<AttrContext> env, Type site,
2535 Name name, KindSelector kind) {
2536 Symbol bestSoFar = typeNotFound;
2537 Symbol sym;
2538 if (kind.contains(KindSelector.VAL)) {
2539 sym = findField(env, site, name, site.tsym);
2540 if (sym.exists()) return sym;
2541 else bestSoFar = bestOf(bestSoFar, sym);
2542 }
2543
2544 if (kind.contains(KindSelector.TYP)) {
2545 sym = findMemberType(env, site, name, site.tsym);
2546 if (sym.exists()) return sym;
2547 else bestSoFar = bestOf(bestSoFar, sym);
2548 }
2549 return bestSoFar;
2550 }
2551
2552 private Symbol checkRestrictedType(DiagnosticPosition pos, Symbol bestSoFar, Name name) {
2553 if (bestSoFar.kind == TYP || bestSoFar.kind == ABSENT_TYP) {
2554 if (allowLocalVariableTypeInference && name.equals(names.var)) {
2555 bestSoFar = new BadRestrictedTypeError(names.var);
2556 } else if (name.equals(names.yield)) {
2557 if (allowYieldStatement) {
2558 bestSoFar = new BadRestrictedTypeError(names.yield);
2559 } else if (pos != null) {
2560 log.warning(pos, Warnings.IllegalRefToRestrictedType(names.yield));
2561 }
2562 }
2563 }
2564 return bestSoFar;
2565 }
2566
2567 /* ***************************************************************************
2568 * Access checking
2569 * The following methods convert ResolveErrors to ErrorSymbols, issuing
2570 * an error message in the process
2571 ****************************************************************************/
2572
2573 /** If `sym' is a bad symbol: report error and return errSymbol
2574 * else pass through unchanged,
2575 * additional arguments duplicate what has been used in trying to find the
2576 * symbol {@literal (--> flyweight pattern)}. This improves performance since we
2577 * expect misses to happen frequently.
2578 *
2579 * @param sym The symbol that was found, or a ResolveError.
2580 * @param pos The position to use for error reporting.
2581 * @param location The symbol the served as a context for this lookup
2582 * @param site The original type from where the selection took place.
2583 * @param name The symbol's name.
2584 * @param qualified Did we get here through a qualified expression resolution?
2585 * @param argtypes The invocation's value arguments,
2586 * if we looked for a method.
2587 * @param typeargtypes The invocation's type arguments,
2588 * if we looked for a method.
2589 * @param logResolveHelper helper class used to log resolve errors
2590 */
2591 Symbol accessInternal(Symbol sym,
2592 DiagnosticPosition pos,
2593 Symbol location,
2594 Type site,
2595 Name name,
2596 boolean qualified,
2597 List<Type> argtypes,
2598 List<Type> typeargtypes,
2599 LogResolveHelper logResolveHelper) {
2600 if (sym.kind.isResolutionError()) {
2601 ResolveError errSym = (ResolveError)sym.baseSymbol();
2602 sym = errSym.access(name, qualified ? site.tsym : syms.noSymbol);
2603 argtypes = logResolveHelper.getArgumentTypes(errSym, sym, name, argtypes);
2604 if (logResolveHelper.resolveDiagnosticNeeded(site, argtypes, typeargtypes)) {
2605 logResolveError(errSym, pos, location, site, name, argtypes, typeargtypes);
2606 }
2607 }
2608 return sym;
2609 }
2610
2611 /**
2612 * Variant of the generalized access routine, to be used for generating method
2613 * resolution diagnostics
2614 */
2615 Symbol accessMethod(Symbol sym,
2616 DiagnosticPosition pos,
2617 Symbol location,
2618 Type site,
2619 Name name,
2620 boolean qualified,
2621 List<Type> argtypes,
2622 List<Type> typeargtypes) {
2623 return accessInternal(sym, pos, location, site, name, qualified, argtypes, typeargtypes, methodLogResolveHelper);
2624 }
2625
2626 /** Same as original accessMethod(), but without location.
2627 */
2628 Symbol accessMethod(Symbol sym,
2629 DiagnosticPosition pos,
2630 Type site,
2631 Name name,
2632 boolean qualified,
2633 List<Type> argtypes,
2634 List<Type> typeargtypes) {
2635 return accessMethod(sym, pos, site.tsym, site, name, qualified, argtypes, typeargtypes);
2636 }
2637
2638 /**
2639 * Variant of the generalized access routine, to be used for generating variable,
2640 * type resolution diagnostics
2641 */
2642 Symbol accessBase(Symbol sym,
2643 DiagnosticPosition pos,
2644 Symbol location,
2645 Type site,
2646 Name name,
2647 boolean qualified) {
2648 return accessInternal(sym, pos, location, site, name, qualified, List.nil(), null, basicLogResolveHelper);
2649 }
2650
2651 /** Same as original accessBase(), but without location.
2652 */
2653 Symbol accessBase(Symbol sym,
2654 DiagnosticPosition pos,
2655 Type site,
2656 Name name,
2657 boolean qualified) {
2658 return accessBase(sym, pos, site.tsym, site, name, qualified);
2659 }
2660
2661 interface LogResolveHelper {
2662 boolean resolveDiagnosticNeeded(Type site, List<Type> argtypes, List<Type> typeargtypes);
2663 List<Type> getArgumentTypes(ResolveError errSym, Symbol accessedSym, Name name, List<Type> argtypes);
2664 }
2665
2666 LogResolveHelper basicLogResolveHelper = new LogResolveHelper() {
2667 public boolean resolveDiagnosticNeeded(Type site, List<Type> argtypes, List<Type> typeargtypes) {
2668 return !site.isErroneous();
2669 }
2670 public List<Type> getArgumentTypes(ResolveError errSym, Symbol accessedSym, Name name, List<Type> argtypes) {
2671 return argtypes;
2672 }
2673 };
2674
2675 LogResolveHelper silentLogResolveHelper = new LogResolveHelper() {
2676 public boolean resolveDiagnosticNeeded(Type site, List<Type> argtypes, List<Type> typeargtypes) {
2677 return false;
2678 }
2679 public List<Type> getArgumentTypes(ResolveError errSym, Symbol accessedSym, Name name, List<Type> argtypes) {
2680 return argtypes;
2681 }
2682 };
2683
2684 LogResolveHelper methodLogResolveHelper = new LogResolveHelper() {
2685 public boolean resolveDiagnosticNeeded(Type site, List<Type> argtypes, List<Type> typeargtypes) {
2686 return !site.isErroneous() &&
2687 !Type.isErroneous(argtypes) &&
2688 (typeargtypes == null || !Type.isErroneous(typeargtypes));
2689 }
2690 public List<Type> getArgumentTypes(ResolveError errSym, Symbol accessedSym, Name name, List<Type> argtypes) {
2691 return argtypes.map(new ResolveDeferredRecoveryMap(AttrMode.SPECULATIVE, accessedSym, currentResolutionContext.step));
2692 }
2693 };
2694
2695 class ResolveDeferredRecoveryMap extends DeferredAttr.RecoveryDeferredTypeMap {
2696
2697 public ResolveDeferredRecoveryMap(AttrMode mode, Symbol msym, MethodResolutionPhase step) {
2698 deferredAttr.super(mode, msym, step);
2699 }
2700
2701 @Override
2702 protected Type typeOf(DeferredType dt, Type pt) {
2703 Type res = super.typeOf(dt, pt);
2704 if (!res.isErroneous()) {
2705 switch (TreeInfo.skipParens(dt.tree).getTag()) {
2706 case LAMBDA:
2707 case REFERENCE:
2708 return dt;
2709 case CONDEXPR:
2710 return res == Type.recoveryType ?
2711 dt : res;
2712 }
2713 }
2714 return res;
2715 }
2716 }
2717
2718 /** Check that sym is not an abstract method.
2719 */
2720 void checkNonAbstract(DiagnosticPosition pos, Symbol sym) {
2721 if ((sym.flags() & ABSTRACT) != 0 && (sym.flags() & DEFAULT) == 0)
2722 log.error(pos,
2723 Errors.AbstractCantBeAccessedDirectly(kindName(sym),sym, sym.location()));
2724 }
2725
2726 /* ***************************************************************************
2727 * Name resolution
2728 * Naming conventions are as for symbol lookup
2729 * Unlike the find... methods these methods will report access errors
2730 ****************************************************************************/
2731
2732 /** Resolve an unqualified (non-method) identifier.
2733 * @param pos The position to use for error reporting.
2734 * @param env The environment current at the identifier use.
2735 * @param name The identifier's name.
2736 * @param kind The set of admissible symbol kinds for the identifier.
2737 */
2738 Symbol resolveIdent(DiagnosticPosition pos, Env<AttrContext> env,
2739 Name name, KindSelector kind) {
2740 return accessBase(
2741 findIdent(pos, env, name, kind),
2742 pos, env.enclClass.sym.type, name, false);
2743 }
2744
2745 /** Resolve an unqualified method identifier.
2746 * @param pos The position to use for error reporting.
2747 * @param env The environment current at the method invocation.
2748 * @param name The identifier's name.
2749 * @param argtypes The types of the invocation's value arguments.
2750 * @param typeargtypes The types of the invocation's type arguments.
2751 */
2752 Symbol resolveMethod(DiagnosticPosition pos,
2753 Env<AttrContext> env,
2754 Name name,
2755 List<Type> argtypes,
2756 List<Type> typeargtypes) {
2757 return lookupMethod(env, pos, env.enclClass.sym, resolveMethodCheck,
2758 new BasicLookupHelper(name, env.enclClass.sym.type, argtypes, typeargtypes) {
2759 @Override
2760 Symbol doLookup(Env<AttrContext> env, MethodResolutionPhase phase) {
2761 return findFun(env, name, argtypes, typeargtypes,
2762 phase.isBoxingRequired(),
2763 phase.isVarargsRequired());
2764 }});
2765 }
2766
2767 /** Resolve a qualified method identifier
2768 * @param pos The position to use for error reporting.
2769 * @param env The environment current at the method invocation.
2770 * @param site The type of the qualifying expression, in which
2771 * identifier is searched.
2772 * @param name The identifier's name.
2773 * @param argtypes The types of the invocation's value arguments.
2774 * @param typeargtypes The types of the invocation's type arguments.
2775 */
2776 Symbol resolveQualifiedMethod(DiagnosticPosition pos, Env<AttrContext> env,
2777 Type site, Name name, List<Type> argtypes,
2778 List<Type> typeargtypes) {
2779 return resolveQualifiedMethod(pos, env, site.tsym, site, name, argtypes, typeargtypes);
2780 }
2781 Symbol resolveQualifiedMethod(DiagnosticPosition pos, Env<AttrContext> env,
2782 Symbol location, Type site, Name name, List<Type> argtypes,
2783 List<Type> typeargtypes) {
2784 return resolveQualifiedMethod(new MethodResolutionContext(), pos, env, location, site, name, argtypes, typeargtypes);
2785 }
2786 private Symbol resolveQualifiedMethod(MethodResolutionContext resolveContext,
2787 DiagnosticPosition pos, Env<AttrContext> env,
2788 Symbol location, Type site, Name name, List<Type> argtypes,
2789 List<Type> typeargtypes) {
2790 return lookupMethod(env, pos, location, resolveContext, new BasicLookupHelper(name, site, argtypes, typeargtypes) {
2791 @Override
2792 Symbol doLookup(Env<AttrContext> env, MethodResolutionPhase phase) {
2793 return findMethod(env, site, name, argtypes, typeargtypes,
2794 phase.isBoxingRequired(),
2795 phase.isVarargsRequired());
2796 }
2797 @Override
2798 Symbol access(Env<AttrContext> env, DiagnosticPosition pos, Symbol location, Symbol sym) {
2799 if (sym.kind.isResolutionError()) {
2800 sym = super.access(env, pos, location, sym);
2801 } else {
2802 MethodSymbol msym = (MethodSymbol)sym;
2803 if ((msym.flags() & SIGNATURE_POLYMORPHIC) != 0) {
2804 env.info.pendingResolutionPhase = BASIC;
2805 return findPolymorphicSignatureInstance(env, sym, argtypes);
2806 }
2807 }
2808 return sym;
2809 }
2810 });
2811 }
2812
2813 /** Find or create an implicit method of exactly the given type (after erasure).
2814 * Searches in a side table, not the main scope of the site.
2815 * This emulates the lookup process required by JSR 292 in JVM.
2816 * @param env Attribution environment
2817 * @param spMethod signature polymorphic method - i.e. MH.invokeExact
2818 * @param argtypes The required argument types
2819 */
2820 Symbol findPolymorphicSignatureInstance(Env<AttrContext> env,
2821 final Symbol spMethod,
2822 List<Type> argtypes) {
2823 Type mtype = infer.instantiatePolymorphicSignatureInstance(env,
2824 (MethodSymbol)spMethod, currentResolutionContext, argtypes);
2825 return findPolymorphicSignatureInstance(spMethod, mtype);
2826 }
2827
2828 Symbol findPolymorphicSignatureInstance(final Symbol spMethod,
2829 Type mtype) {
2830 for (Symbol sym : polymorphicSignatureScope.getSymbolsByName(spMethod.name)) {
2831 // Check that there is already a method symbol for the method
2832 // type and owner
2833 if (types.isSameType(mtype, sym.type) &&
2834 spMethod.owner == sym.owner) {
2835 return sym;
2836 }
2837 }
2838
2839 Type spReturnType = spMethod.asType().getReturnType();
2840 if (types.isSameType(spReturnType, syms.objectType)) {
2841 // Polymorphic return, pass through mtype
2842 } else if (!types.isSameType(spReturnType, mtype.getReturnType())) {
2843 // Retain the sig poly method's return type, which differs from that of mtype
2844 // Will result in an incompatible return type error
2845 mtype = new MethodType(mtype.getParameterTypes(),
2846 spReturnType,
2847 mtype.getThrownTypes(),
2848 syms.methodClass);
2849 }
2850
2851 // Create the desired method
2852 // Retain static modifier is to support invocations to
2853 // MethodHandle.linkTo* methods
2854 long flags = ABSTRACT | HYPOTHETICAL |
2855 spMethod.flags() & (Flags.AccessFlags | Flags.STATIC);
2856 Symbol msym = new MethodSymbol(flags, spMethod.name, mtype, spMethod.owner) {
2857 @Override
2858 public Symbol baseSymbol() {
2859 return spMethod;
2860 }
2861 };
2862 if (!mtype.isErroneous()) { // Cache only if kosher.
2863 polymorphicSignatureScope.enter(msym);
2864 }
2865 return msym;
2866 }
2867
2868 /** Resolve a qualified method identifier, throw a fatal error if not
2869 * found.
2870 * @param pos The position to use for error reporting.
2871 * @param env The environment current at the method invocation.
2872 * @param site The type of the qualifying expression, in which
2873 * identifier is searched.
2874 * @param name The identifier's name.
2875 * @param argtypes The types of the invocation's value arguments.
2876 * @param typeargtypes The types of the invocation's type arguments.
2877 */
2878 public MethodSymbol resolveInternalMethod(DiagnosticPosition pos, Env<AttrContext> env,
2879 Type site, Name name,
2880 List<Type> argtypes,
2881 List<Type> typeargtypes) {
2882 MethodResolutionContext resolveContext = new MethodResolutionContext();
2883 resolveContext.internalResolution = true;
2884 Symbol sym = resolveQualifiedMethod(resolveContext, pos, env, site.tsym,
2885 site, name, argtypes, typeargtypes);
2886 if (sym.kind == MTH) return (MethodSymbol)sym;
2887 else throw new FatalError(
2888 diags.fragment(Fragments.FatalErrCantLocateMeth(name)));
2889 }
2890
2891 /** Resolve constructor.
2892 * @param pos The position to use for error reporting.
2893 * @param env The environment current at the constructor invocation.
2894 * @param site The type of class for which a constructor is searched.
2895 * @param argtypes The types of the constructor invocation's value
2896 * arguments.
2897 * @param typeargtypes The types of the constructor invocation's type
2898 * arguments.
2899 */
2900 Symbol resolveConstructor(DiagnosticPosition pos,
2901 Env<AttrContext> env,
2902 Type site,
2903 List<Type> argtypes,
2904 List<Type> typeargtypes) {
2905 return resolveConstructor(new MethodResolutionContext(), pos, env, site, argtypes, typeargtypes);
2906 }
2907
2908 private Symbol resolveConstructor(MethodResolutionContext resolveContext,
2909 final DiagnosticPosition pos,
2910 Env<AttrContext> env,
2911 Type site,
2912 List<Type> argtypes,
2913 List<Type> typeargtypes) {
2914 return lookupMethod(env, pos, site.tsym, resolveContext, new BasicLookupHelper(names.init, site, argtypes, typeargtypes) {
2915 @Override
2916 Symbol doLookup(Env<AttrContext> env, MethodResolutionPhase phase) {
2917 return findConstructor(pos, env, site, argtypes, typeargtypes,
2918 phase.isBoxingRequired(),
2919 phase.isVarargsRequired());
2920 }
2921 });
2922 }
2923
2924 /** Resolve a constructor, throw a fatal error if not found.
2925 * @param pos The position to use for error reporting.
2926 * @param env The environment current at the method invocation.
2927 * @param site The type to be constructed.
2928 * @param argtypes The types of the invocation's value arguments.
2929 * @param typeargtypes The types of the invocation's type arguments.
2930 */
2931 public MethodSymbol resolveInternalConstructor(DiagnosticPosition pos, Env<AttrContext> env,
2932 Type site,
2933 List<Type> argtypes,
2934 List<Type> typeargtypes) {
2935 MethodResolutionContext resolveContext = new MethodResolutionContext();
2936 resolveContext.internalResolution = true;
2937 Symbol sym = resolveConstructor(resolveContext, pos, env, site, argtypes, typeargtypes);
2938 if (sym.kind == MTH) return (MethodSymbol)sym;
2939 else throw new FatalError(
2940 diags.fragment(Fragments.FatalErrCantLocateCtor(site)));
2941 }
2942
2943 Symbol findConstructor(DiagnosticPosition pos, Env<AttrContext> env,
2944 Type site, List<Type> argtypes,
2945 List<Type> typeargtypes,
2946 boolean allowBoxing,
2947 boolean useVarargs) {
2948 Symbol sym = findMethod(env, site,
2949 names.init, argtypes,
2950 typeargtypes, allowBoxing,
2951 useVarargs);
2952 chk.checkDeprecated(pos, env.info.scope.owner, sym);
2953 chk.checkPreview(pos, env.info.scope.owner, sym);
2954 return sym;
2955 }
2956
2957 /** Resolve constructor using diamond inference.
2958 * @param pos The position to use for error reporting.
2959 * @param env The environment current at the constructor invocation.
2960 * @param site The type of class for which a constructor is searched.
2961 * The scope of this class has been touched in attribution.
2962 * @param argtypes The types of the constructor invocation's value
2963 * arguments.
2964 * @param typeargtypes The types of the constructor invocation's type
2965 * arguments.
2966 */
2967 Symbol resolveDiamond(DiagnosticPosition pos,
2968 Env<AttrContext> env,
2969 Type site,
2970 List<Type> argtypes,
2971 List<Type> typeargtypes) {
2972 return lookupMethod(env, pos, site.tsym, resolveMethodCheck,
2973 new BasicLookupHelper(names.init, site, argtypes, typeargtypes) {
2974 @Override
2975 Symbol doLookup(Env<AttrContext> env, MethodResolutionPhase phase) {
2976 return findDiamond(pos, env, site, argtypes, typeargtypes,
2977 phase.isBoxingRequired(),
2978 phase.isVarargsRequired());
2979 }
2980 @Override
2981 Symbol access(Env<AttrContext> env, DiagnosticPosition pos, Symbol location, Symbol sym) {
2982 if (sym.kind.isResolutionError()) {
2983 if (sym.kind != WRONG_MTH &&
2984 sym.kind != WRONG_MTHS) {
2985 sym = super.access(env, pos, location, sym);
2986 } else {
2987 sym = new DiamondError(sym, currentResolutionContext);
2988 sym = accessMethod(sym, pos, site, names.init, true, argtypes, typeargtypes);
2989 env.info.pendingResolutionPhase = currentResolutionContext.step;
2990 }
2991 }
2992 return sym;
2993 }});
2994 }
2995
2996 /** Find the constructor using diamond inference and do some checks(deprecated and preview).
2997 * @param pos The position to use for error reporting.
2998 * @param env The environment current at the constructor invocation.
2999 * @param site The type of class for which a constructor is searched.
3000 * The scope of this class has been touched in attribution.
3001 * @param argtypes The types of the constructor invocation's value arguments.
3002 * @param typeargtypes The types of the constructor invocation's type arguments.
3003 * @param allowBoxing Allow boxing conversions of arguments.
3004 * @param useVarargs Box trailing arguments into an array for varargs.
3005 */
3006 private Symbol findDiamond(DiagnosticPosition pos,
3007 Env<AttrContext> env,
3008 Type site,
3009 List<Type> argtypes,
3010 List<Type> typeargtypes,
3011 boolean allowBoxing,
3012 boolean useVarargs) {
3013 Symbol sym = findDiamond(env, site, argtypes, typeargtypes, allowBoxing, useVarargs);
3014 chk.checkDeprecated(pos, env.info.scope.owner, sym);
3015 chk.checkPreview(pos, env.info.scope.owner, sym);
3016 return sym;
3017 }
3018
3019 /** This method scans all the constructor symbol in a given class scope -
3020 * assuming that the original scope contains a constructor of the kind:
3021 * {@code Foo(X x, Y y)}, where X,Y are class type-variables declared in Foo,
3022 * a method check is executed against the modified constructor type:
3023 * {@code <X,Y>Foo<X,Y>(X x, Y y)}. This is crucial in order to enable diamond
3024 * inference. The inferred return type of the synthetic constructor IS
3025 * the inferred type for the diamond operator.
3026 */
3027 private Symbol findDiamond(Env<AttrContext> env,
3028 Type site,
3029 List<Type> argtypes,
3030 List<Type> typeargtypes,
3031 boolean allowBoxing,
3032 boolean useVarargs) {
3033 Symbol bestSoFar = methodNotFound;
3034 TypeSymbol tsym = site.tsym.isInterface() ? syms.objectType.tsym : site.tsym;
3035 for (final Symbol sym : tsym.members().getSymbolsByName(names.init)) {
3036 //- System.out.println(" e " + e.sym);
3037 if (sym.kind == MTH &&
3038 (sym.flags_field & SYNTHETIC) == 0) {
3039 List<Type> oldParams = sym.type.hasTag(FORALL) ?
3040 ((ForAll)sym.type).tvars :
3041 List.nil();
3042 Type constrType = new ForAll(site.tsym.type.getTypeArguments().appendList(oldParams),
3043 types.createMethodTypeWithReturn(sym.type.asMethodType(), site));
3044 MethodSymbol newConstr = new MethodSymbol(sym.flags(), names.init, constrType, site.tsym) {
3045 @Override
3046 public Symbol baseSymbol() {
3047 return sym;
3048 }
3049 };
3050 bestSoFar = selectBest(env, site, argtypes, typeargtypes,
3051 newConstr,
3052 bestSoFar,
3053 allowBoxing,
3054 useVarargs);
3055 }
3056 }
3057 return bestSoFar;
3058 }
3059
3060 Symbol getMemberReference(DiagnosticPosition pos,
3061 Env<AttrContext> env,
3062 JCMemberReference referenceTree,
3063 Type site,
3064 Name name) {
3065
3066 site = types.capture(site);
3067
3068 ReferenceLookupHelper lookupHelper = makeReferenceLookupHelper(
3069 referenceTree, site, name, List.nil(), null, VARARITY);
3070
3071 Env<AttrContext> newEnv = env.dup(env.tree, env.info.dup());
3072 Symbol sym = lookupMethod(newEnv, env.tree.pos(), site.tsym,
3073 nilMethodCheck, lookupHelper);
3074
3075 env.info.pendingResolutionPhase = newEnv.info.pendingResolutionPhase;
3076
3077 return sym;
3078 }
3079
3080 ReferenceLookupHelper makeReferenceLookupHelper(JCMemberReference referenceTree,
3081 Type site,
3082 Name name,
3083 List<Type> argtypes,
3084 List<Type> typeargtypes,
3085 MethodResolutionPhase maxPhase) {
3086 if (!name.equals(names.init)) {
3087 //method reference
3088 return new MethodReferenceLookupHelper(referenceTree, name, site, argtypes, typeargtypes, maxPhase);
3089 } else if (site.hasTag(ARRAY)) {
3090 //array constructor reference
3091 return new ArrayConstructorReferenceLookupHelper(referenceTree, site, argtypes, typeargtypes, maxPhase);
3092 } else {
3093 //class constructor reference
3094 return new ConstructorReferenceLookupHelper(referenceTree, site, argtypes, typeargtypes, maxPhase);
3095 }
3096 }
3097
3098 /**
3099 * Resolution of member references is typically done as a single
3100 * overload resolution step, where the argument types A are inferred from
3101 * the target functional descriptor.
3102 *
3103 * If the member reference is a method reference with a type qualifier,
3104 * a two-step lookup process is performed. The first step uses the
3105 * expected argument list A, while the second step discards the first
3106 * type from A (which is treated as a receiver type).
3107 *
3108 * There are two cases in which inference is performed: (i) if the member
3109 * reference is a constructor reference and the qualifier type is raw - in
3110 * which case diamond inference is used to infer a parameterization for the
3111 * type qualifier; (ii) if the member reference is an unbound reference
3112 * where the type qualifier is raw - in that case, during the unbound lookup
3113 * the receiver argument type is used to infer an instantiation for the raw
3114 * qualifier type.
3115 *
3116 * When a multi-step resolution process is exploited, the process of picking
3117 * the resulting symbol is delegated to an helper class {@link com.sun.tools.javac.comp.Resolve.ReferenceChooser}.
3118 *
3119 * This routine returns a pair (T,S), where S is the member reference symbol,
3120 * and T is the type of the class in which S is defined. This is necessary as
3121 * the type T might be dynamically inferred (i.e. if constructor reference
3122 * has a raw qualifier).
3123 */
3124 Pair<Symbol, ReferenceLookupHelper> resolveMemberReference(Env<AttrContext> env,
3125 JCMemberReference referenceTree,
3126 Type site,
3127 Name name,
3128 List<Type> argtypes,
3129 List<Type> typeargtypes,
3130 Type descriptor,
3131 MethodCheck methodCheck,
3132 InferenceContext inferenceContext,
3133 ReferenceChooser referenceChooser) {
3134
3135 //step 1 - bound lookup
3136 ReferenceLookupHelper boundLookupHelper = makeReferenceLookupHelper(
3137 referenceTree, site, name, argtypes, typeargtypes, VARARITY);
3138 Env<AttrContext> boundEnv = env.dup(env.tree, env.info.dup());
3139 MethodResolutionContext boundSearchResolveContext = new MethodResolutionContext();
3140 boundSearchResolveContext.methodCheck = methodCheck;
3141 Symbol boundSym = lookupMethod(boundEnv, env.tree.pos(),
3142 site.tsym, boundSearchResolveContext, boundLookupHelper);
3143 boolean isStaticSelector = TreeInfo.isStaticSelector(referenceTree.expr, names);
3144 ReferenceLookupResult boundRes = new ReferenceLookupResult(boundSym, boundSearchResolveContext, isStaticSelector);
3145 if (dumpMethodReferenceSearchResults) {
3146 dumpMethodReferenceSearchResults(referenceTree, boundSearchResolveContext, boundSym, true);
3147 }
3148
3149 //step 2 - unbound lookup
3150 Symbol unboundSym = methodNotFound;
3151 Env<AttrContext> unboundEnv = env.dup(env.tree, env.info.dup());
3152 ReferenceLookupHelper unboundLookupHelper = boundLookupHelper.unboundLookup(inferenceContext);
3153 ReferenceLookupResult unboundRes = referenceNotFound;
3154 if (unboundLookupHelper != null) {
3155 MethodResolutionContext unboundSearchResolveContext =
3156 new MethodResolutionContext();
3157 unboundSearchResolveContext.methodCheck = methodCheck;
3158 unboundSym = lookupMethod(unboundEnv, env.tree.pos(),
3159 site.tsym, unboundSearchResolveContext, unboundLookupHelper);
3160 unboundRes = new ReferenceLookupResult(unboundSym, unboundSearchResolveContext, isStaticSelector);
3161 if (dumpMethodReferenceSearchResults) {
3162 dumpMethodReferenceSearchResults(referenceTree, unboundSearchResolveContext, unboundSym, false);
3163 }
3164 }
3165
3166 //merge results
3167 Pair<Symbol, ReferenceLookupHelper> res;
3168 ReferenceLookupResult bestRes = referenceChooser.result(boundRes, unboundRes);
3169 res = new Pair<>(bestRes.sym,
3170 bestRes == unboundRes ? unboundLookupHelper : boundLookupHelper);
3171 env.info.pendingResolutionPhase = bestRes == unboundRes ?
3172 unboundEnv.info.pendingResolutionPhase :
3173 boundEnv.info.pendingResolutionPhase;
3174
3175 if (!res.fst.kind.isResolutionError()) {
3176 //handle sigpoly method references
3177 MethodSymbol msym = (MethodSymbol)res.fst;
3178 if ((msym.flags() & SIGNATURE_POLYMORPHIC) != 0) {
3179 env.info.pendingResolutionPhase = BASIC;
3180 res = new Pair<>(findPolymorphicSignatureInstance(msym, descriptor), res.snd);
3181 }
3182 }
3183
3184 return res;
3185 }
3186
3187 private void dumpMethodReferenceSearchResults(JCMemberReference referenceTree,
3188 MethodResolutionContext resolutionContext,
3189 Symbol bestSoFar,
3190 boolean bound) {
3191 ListBuffer<JCDiagnostic> subDiags = new ListBuffer<>();
3192 int pos = 0;
3193 int mostSpecificPos = -1;
3194 for (Candidate c : resolutionContext.candidates) {
3195 if (resolutionContext.step != c.step || !c.isApplicable()) {
3196 continue;
3197 } else {
3198 JCDiagnostic subDiag = null;
3199 if (c.sym.type.hasTag(FORALL)) {
3200 subDiag = diags.fragment(Fragments.PartialInstSig(c.mtype));
3201 }
3202
3203 String key = subDiag == null ?
3204 "applicable.method.found.2" :
3205 "applicable.method.found.3";
3206 subDiags.append(diags.fragment(key, pos,
3207 c.sym.isStatic() ? Fragments.Static : Fragments.NonStatic, c.sym, subDiag));
3208 if (c.sym == bestSoFar)
3209 mostSpecificPos = pos;
3210 pos++;
3211 }
3212 }
3213 JCDiagnostic main = diags.note(
3214 log.currentSource(),
3215 referenceTree,
3216 "method.ref.search.results.multi",
3217 bound ? Fragments.Bound : Fragments.Unbound,
3218 referenceTree.toString(), mostSpecificPos);
3219 JCDiagnostic d = new JCDiagnostic.MultilineDiagnostic(main, subDiags.toList());
3220 log.report(d);
3221 }
3222
3223 /**
3224 * This class is used to represent a method reference lookup result. It keeps track of two
3225 * things: (i) the symbol found during a method reference lookup and (ii) the static kind
3226 * of the lookup (see {@link com.sun.tools.javac.comp.Resolve.ReferenceLookupResult.StaticKind}).
3227 */
3228 static class ReferenceLookupResult {
3229
3230 /**
3231 * Static kind associated with a method reference lookup. Erroneous lookups end up with
3232 * the UNDEFINED kind; successful lookups will end up with either STATIC, NON_STATIC,
3233 * depending on whether all applicable candidates are static or non-static methods,
3234 * respectively. If a successful lookup has both static and non-static applicable methods,
3235 * its kind is set to BOTH.
3236 */
3237 enum StaticKind {
3238 STATIC,
3239 NON_STATIC,
3240 BOTH,
3241 UNDEFINED;
3242
3243 /**
3244 * Retrieve the static kind associated with a given (method) symbol.
3245 */
3246 static StaticKind from(Symbol s) {
3247 return s.isStatic() ?
3248 STATIC : NON_STATIC;
3249 }
3250
3251 /**
3252 * Merge two static kinds together.
3253 */
3254 static StaticKind reduce(StaticKind sk1, StaticKind sk2) {
3255 if (sk1 == UNDEFINED) {
3256 return sk2;
3257 } else if (sk2 == UNDEFINED) {
3258 return sk1;
3259 } else {
3260 return sk1 == sk2 ? sk1 : BOTH;
3261 }
3262 }
3263 }
3264
3265 /** The static kind. */
3266 StaticKind staticKind;
3267
3268 /** The lookup result. */
3269 Symbol sym;
3270
3271 ReferenceLookupResult(Symbol sym, MethodResolutionContext resolutionContext, boolean isStaticSelector) {
3272 this(sym, staticKind(sym, resolutionContext, isStaticSelector));
3273 }
3274
3275 private ReferenceLookupResult(Symbol sym, StaticKind staticKind) {
3276 this.staticKind = staticKind;
3277 this.sym = sym;
3278 }
3279
3280 private static StaticKind staticKind(Symbol sym, MethodResolutionContext resolutionContext, boolean isStaticSelector) {
3281 if (sym.kind == MTH && !isStaticSelector) {
3282 return StaticKind.from(sym);
3283 } else if (sym.kind == MTH || sym.kind == AMBIGUOUS) {
3284 return resolutionContext.candidates.stream()
3285 .filter(c -> c.isApplicable() && c.step == resolutionContext.step)
3286 .map(c -> StaticKind.from(c.sym))
3287 .reduce(StaticKind::reduce)
3288 .orElse(StaticKind.UNDEFINED);
3289 } else {
3290 return StaticKind.UNDEFINED;
3291 }
3292 }
3293
3294 /**
3295 * Does this result corresponds to a successful lookup (i.e. one where a method has been found?)
3296 */
3297 boolean isSuccess() {
3298 return staticKind != StaticKind.UNDEFINED;
3299 }
3300
3301 /**
3302 * Does this result have given static kind?
3303 */
3304 boolean hasKind(StaticKind sk) {
3305 return this.staticKind == sk;
3306 }
3307
3308 /**
3309 * Error recovery helper: can this lookup result be ignored (for the purpose of returning
3310 * some 'better' result) ?
3311 */
3312 boolean canIgnore() {
3313 switch (sym.kind) {
3314 case ABSENT_MTH:
3315 return true;
3316 case WRONG_MTH:
3317 InapplicableSymbolError errSym =
3318 (InapplicableSymbolError)sym.baseSymbol();
3319 return new Template(MethodCheckDiag.ARITY_MISMATCH.regex())
3320 .matches(errSym.errCandidate().snd);
3321 case WRONG_MTHS:
3322 InapplicableSymbolsError errSyms =
3323 (InapplicableSymbolsError)sym.baseSymbol();
3324 return errSyms.filterCandidates(errSyms.mapCandidates()).isEmpty();
3325 default:
3326 return false;
3327 }
3328 }
3329
3330 static ReferenceLookupResult error(Symbol sym) {
3331 return new ReferenceLookupResult(sym, StaticKind.UNDEFINED);
3332 }
3333 }
3334
3335 /**
3336 * This abstract class embodies the logic that converts one (bound lookup) or two (unbound lookup)
3337 * {@code ReferenceLookupResult} objects into a {@code Symbol}, which is then regarded as the
3338 * result of method reference resolution.
3339 */
3340 abstract class ReferenceChooser {
3341 /**
3342 * Generate a result from a pair of lookup result objects. This method delegates to the
3343 * appropriate result generation routine.
3344 */
3345 ReferenceLookupResult result(ReferenceLookupResult boundRes, ReferenceLookupResult unboundRes) {
3346 return unboundRes != referenceNotFound ?
3347 unboundResult(boundRes, unboundRes) :
3348 boundResult(boundRes);
3349 }
3350
3351 /**
3352 * Generate a symbol from a given bound lookup result.
3353 */
3354 abstract ReferenceLookupResult boundResult(ReferenceLookupResult boundRes);
3355
3356 /**
3357 * Generate a symbol from a pair of bound/unbound lookup results.
3358 */
3359 abstract ReferenceLookupResult unboundResult(ReferenceLookupResult boundRes, ReferenceLookupResult unboundRes);
3360 }
3361
3362 /**
3363 * This chooser implements the selection strategy used during a full lookup; this logic
3364 * is described in JLS SE 8 (15.3.2).
3365 */
3366 ReferenceChooser basicReferenceChooser = new ReferenceChooser() {
3367
3368 @Override
3369 ReferenceLookupResult boundResult(ReferenceLookupResult boundRes) {
3370 return !boundRes.isSuccess() || boundRes.hasKind(StaticKind.NON_STATIC) ?
3371 boundRes : //the search produces a non-static method
3372 ReferenceLookupResult.error(new BadMethodReferenceError(boundRes.sym, false));
3373 }
3374
3375 @Override
3376 ReferenceLookupResult unboundResult(ReferenceLookupResult boundRes, ReferenceLookupResult unboundRes) {
3377 if (boundRes.isSuccess() && boundRes.sym.isStatic() &&
3378 (!unboundRes.isSuccess() || unboundRes.hasKind(StaticKind.STATIC))) {
3379 //the first search produces a static method and no non-static method is applicable
3380 //during the second search
3381 return boundRes;
3382 } else if (unboundRes.isSuccess() && !unboundRes.sym.isStatic() &&
3383 (!boundRes.isSuccess() || boundRes.hasKind(StaticKind.NON_STATIC))) {
3384 //the second search produces a non-static method and no static method is applicable
3385 //during the first search
3386 return unboundRes;
3387 } else if (boundRes.isSuccess() && unboundRes.isSuccess()) {
3388 //both searches produce some result; ambiguity (error recovery)
3389 return ReferenceLookupResult.error(ambiguityError(boundRes.sym, unboundRes.sym));
3390 } else if (boundRes.isSuccess() || unboundRes.isSuccess()) {
3391 //Both searches failed to produce a result with correct staticness (i.e. first search
3392 //produces an non-static method). Alternatively, a given search produced a result
3393 //with the right staticness, but the other search has applicable methods with wrong
3394 //staticness (error recovery)
3395 return ReferenceLookupResult.error(new BadMethodReferenceError(boundRes.isSuccess() ?
3396 boundRes.sym : unboundRes.sym, true));
3397 } else {
3398 //both searches fail to produce a result - pick 'better' error using heuristics (error recovery)
3399 return (boundRes.canIgnore() && !unboundRes.canIgnore()) ?
3400 unboundRes : boundRes;
3401 }
3402 }
3403 };
3404
3405 /**
3406 * This chooser implements the selection strategy used during an arity-based lookup; this logic
3407 * is described in JLS SE 8 (15.12.2.1).
3408 */
3409 ReferenceChooser structuralReferenceChooser = new ReferenceChooser() {
3410
3411 @Override
3412 ReferenceLookupResult boundResult(ReferenceLookupResult boundRes) {
3413 return (!boundRes.isSuccess() || !boundRes.hasKind(StaticKind.STATIC)) ?
3414 boundRes : //the search has at least one applicable non-static method
3415 ReferenceLookupResult.error(new BadMethodReferenceError(boundRes.sym, false));
3416 }
3417
3418 @Override
3419 ReferenceLookupResult unboundResult(ReferenceLookupResult boundRes, ReferenceLookupResult unboundRes) {
3420 if (boundRes.isSuccess() && !boundRes.hasKind(StaticKind.NON_STATIC)) {
3421 //the first search has at least one applicable static method
3422 return boundRes;
3423 } else if (unboundRes.isSuccess() && !unboundRes.hasKind(StaticKind.STATIC)) {
3424 //the second search has at least one applicable non-static method
3425 return unboundRes;
3426 } else if (boundRes.isSuccess() || unboundRes.isSuccess()) {
3427 //either the first search produces a non-static method, or second search produces
3428 //a non-static method (error recovery)
3429 return ReferenceLookupResult.error(new BadMethodReferenceError(boundRes.isSuccess() ?
3430 boundRes.sym : unboundRes.sym, true));
3431 } else {
3432 //both searches fail to produce a result - pick 'better' error using heuristics (error recovery)
3433 return (boundRes.canIgnore() && !unboundRes.canIgnore()) ?
3434 unboundRes : boundRes;
3435 }
3436 }
3437 };
3438
3439 /**
3440 * Helper for defining custom method-like lookup logic; a lookup helper
3441 * provides hooks for (i) the actual lookup logic and (ii) accessing the
3442 * lookup result (this step might result in compiler diagnostics to be generated)
3443 */
3444 abstract class LookupHelper {
3445
3446 /** name of the symbol to lookup */
3447 Name name;
3448
3449 /** location in which the lookup takes place */
3450 Type site;
3451
3452 /** actual types used during the lookup */
3453 List<Type> argtypes;
3454
3455 /** type arguments used during the lookup */
3456 List<Type> typeargtypes;
3457
3458 /** Max overload resolution phase handled by this helper */
3459 MethodResolutionPhase maxPhase;
3460
3461 LookupHelper(Name name, Type site, List<Type> argtypes, List<Type> typeargtypes, MethodResolutionPhase maxPhase) {
3462 this.name = name;
3463 this.site = site;
3464 this.argtypes = argtypes;
3465 this.typeargtypes = typeargtypes;
3466 this.maxPhase = maxPhase;
3467 }
3468
3469 /**
3470 * Should lookup stop at given phase with given result
3471 */
3472 final boolean shouldStop(Symbol sym, MethodResolutionPhase phase) {
3473 return phase.ordinal() > maxPhase.ordinal() ||
3474 !sym.kind.isResolutionError() || sym.kind == AMBIGUOUS || sym.kind == STATICERR;
3475 }
3476
3477 /**
3478 * Search for a symbol under a given overload resolution phase - this method
3479 * is usually called several times, once per each overload resolution phase
3480 */
3481 abstract Symbol lookup(Env<AttrContext> env, MethodResolutionPhase phase);
3482
3483 /**
3484 * Dump overload resolution info
3485 */
3486 void debug(DiagnosticPosition pos, Symbol sym) {
3487 //do nothing
3488 }
3489
3490 /**
3491 * Validate the result of the lookup
3492 */
3493 abstract Symbol access(Env<AttrContext> env, DiagnosticPosition pos, Symbol location, Symbol sym);
3494 }
3495
3496 abstract class BasicLookupHelper extends LookupHelper {
3497
3498 BasicLookupHelper(Name name, Type site, List<Type> argtypes, List<Type> typeargtypes) {
3499 this(name, site, argtypes, typeargtypes, MethodResolutionPhase.VARARITY);
3500 }
3501
3502 BasicLookupHelper(Name name, Type site, List<Type> argtypes, List<Type> typeargtypes, MethodResolutionPhase maxPhase) {
3503 super(name, site, argtypes, typeargtypes, maxPhase);
3504 }
3505
3506 @Override
3507 final Symbol lookup(Env<AttrContext> env, MethodResolutionPhase phase) {
3508 Symbol sym = doLookup(env, phase);
3509 if (sym.kind == AMBIGUOUS) {
3510 AmbiguityError a_err = (AmbiguityError)sym.baseSymbol();
3511 sym = a_err.mergeAbstracts(site);
3512 }
3513 return sym;
3514 }
3515
3516 abstract Symbol doLookup(Env<AttrContext> env, MethodResolutionPhase phase);
3517
3518 @Override
3519 Symbol access(Env<AttrContext> env, DiagnosticPosition pos, Symbol location, Symbol sym) {
3520 if (sym.kind.isResolutionError()) {
3521 //if nothing is found return the 'first' error
3522 sym = accessMethod(sym, pos, location, site, name, true, argtypes, typeargtypes);
3523 }
3524 return sym;
3525 }
3526
3527 @Override
3528 void debug(DiagnosticPosition pos, Symbol sym) {
3529 reportVerboseResolutionDiagnostic(pos, name, site, argtypes, typeargtypes, sym);
3530 }
3531 }
3532
3533 /**
3534 * Helper class for member reference lookup. A reference lookup helper
3535 * defines the basic logic for member reference lookup; a method gives
3536 * access to an 'unbound' helper used to perform an unbound member
3537 * reference lookup.
3538 */
3539 abstract class ReferenceLookupHelper extends LookupHelper {
3540
3541 /** The member reference tree */
3542 JCMemberReference referenceTree;
3543
3544 ReferenceLookupHelper(JCMemberReference referenceTree, Name name, Type site,
3545 List<Type> argtypes, List<Type> typeargtypes, MethodResolutionPhase maxPhase) {
3546 super(name, site, argtypes, typeargtypes, maxPhase);
3547 this.referenceTree = referenceTree;
3548 }
3549
3550 /**
3551 * Returns an unbound version of this lookup helper. By default, this
3552 * method returns an dummy lookup helper.
3553 */
3554 ReferenceLookupHelper unboundLookup(InferenceContext inferenceContext) {
3555 return null;
3556 }
3557
3558 /**
3559 * Get the kind of the member reference
3560 */
3561 abstract JCMemberReference.ReferenceKind referenceKind(Symbol sym);
3562
3563 Symbol access(Env<AttrContext> env, DiagnosticPosition pos, Symbol location, Symbol sym) {
3564 if (sym.kind == AMBIGUOUS) {
3565 AmbiguityError a_err = (AmbiguityError)sym.baseSymbol();
3566 sym = a_err.mergeAbstracts(site);
3567 }
3568 //skip error reporting
3569 return sym;
3570 }
3571 }
3572
3573 /**
3574 * Helper class for method reference lookup. The lookup logic is based
3575 * upon Resolve.findMethod; in certain cases, this helper class has a
3576 * corresponding unbound helper class (see UnboundMethodReferenceLookupHelper).
3577 * In such cases, non-static lookup results are thrown away.
3578 */
3579 class MethodReferenceLookupHelper extends ReferenceLookupHelper {
3580
3581 /** The original method reference lookup site. */
3582 Type originalSite;
3583
3584 MethodReferenceLookupHelper(JCMemberReference referenceTree, Name name, Type site,
3585 List<Type> argtypes, List<Type> typeargtypes, MethodResolutionPhase maxPhase) {
3586 super(referenceTree, name, types.skipTypeVars(site, true), argtypes, typeargtypes, maxPhase);
3587 this.originalSite = site;
3588 }
3589
3590 @Override
3591 final Symbol lookup(Env<AttrContext> env, MethodResolutionPhase phase) {
3592 return findMethod(env, site, name, argtypes, typeargtypes,
3593 phase.isBoxingRequired(), phase.isVarargsRequired());
3594 }
3595
3596 @Override
3597 ReferenceLookupHelper unboundLookup(InferenceContext inferenceContext) {
3598 if (TreeInfo.isStaticSelector(referenceTree.expr, names)) {
3599 if (argtypes.nonEmpty() &&
3600 (argtypes.head.hasTag(NONE) ||
3601 types.isSubtypeUnchecked(inferenceContext.asUndetVar(argtypes.head), originalSite))) {
3602 return new UnboundMethodReferenceLookupHelper(referenceTree, name,
3603 originalSite, argtypes, typeargtypes, maxPhase);
3604 } else {
3605 return new ReferenceLookupHelper(referenceTree, name, site, argtypes, typeargtypes, maxPhase) {
3606 @Override
3607 ReferenceLookupHelper unboundLookup(InferenceContext inferenceContext) {
3608 return this;
3609 }
3610
3611 @Override
3612 Symbol lookup(Env<AttrContext> env, MethodResolutionPhase phase) {
3613 return methodNotFound;
3614 }
3615
3616 @Override
3617 ReferenceKind referenceKind(Symbol sym) {
3618 Assert.error();
3619 return null;
3620 }
3621 };
3622 }
3623 } else {
3624 return super.unboundLookup(inferenceContext);
3625 }
3626 }
3627
3628 @Override
3629 ReferenceKind referenceKind(Symbol sym) {
3630 if (sym.isStatic()) {
3631 return ReferenceKind.STATIC;
3632 } else {
3633 Name selName = TreeInfo.name(referenceTree.getQualifierExpression());
3634 return selName != null && selName == names._super ?
3635 ReferenceKind.SUPER :
3636 ReferenceKind.BOUND;
3637 }
3638 }
3639
3640 @Override
3641 Symbol access(Env<AttrContext> env, DiagnosticPosition pos, Symbol location, Symbol sym) {
3642 if (originalSite.hasTag(TYPEVAR) && sym.kind == MTH) {
3643 sym = (sym.flags() & Flags.PRIVATE) != 0 ?
3644 new AccessError(env, site, sym) :
3645 sym;
3646 return accessBase(sym, pos, location, originalSite, name, true);
3647 } else {
3648 return super.access(env, pos, location, sym);
3649 }
3650 }
3651 }
3652
3653 /**
3654 * Helper class for unbound method reference lookup. Essentially the same
3655 * as the basic method reference lookup helper; main difference is that static
3656 * lookup results are thrown away. If qualifier type is raw, an attempt to
3657 * infer a parameterized type is made using the first actual argument (that
3658 * would otherwise be ignored during the lookup).
3659 */
3660 class UnboundMethodReferenceLookupHelper extends MethodReferenceLookupHelper {
3661
3662 UnboundMethodReferenceLookupHelper(JCMemberReference referenceTree, Name name, Type site,
3663 List<Type> argtypes, List<Type> typeargtypes, MethodResolutionPhase maxPhase) {
3664 super(referenceTree, name, site, argtypes.tail, typeargtypes, maxPhase);
3665 if (site.isRaw() && !argtypes.head.hasTag(NONE)) {
3666 Type asSuperSite = types.asSuper(argtypes.head, site.tsym);
3667 this.site = types.skipTypeVars(asSuperSite, true);
3668 }
3669 }
3670
3671 @Override
3672 ReferenceLookupHelper unboundLookup(InferenceContext inferenceContext) {
3673 return this;
3674 }
3675
3676 @Override
3677 ReferenceKind referenceKind(Symbol sym) {
3678 return ReferenceKind.UNBOUND;
3679 }
3680 }
3681
3682 /**
3683 * Helper class for array constructor lookup; an array constructor lookup
3684 * is simulated by looking up a method that returns the array type specified
3685 * as qualifier, and that accepts a single int parameter (size of the array).
3686 */
3687 class ArrayConstructorReferenceLookupHelper extends ReferenceLookupHelper {
3688
3689 ArrayConstructorReferenceLookupHelper(JCMemberReference referenceTree, Type site, List<Type> argtypes,
3690 List<Type> typeargtypes, MethodResolutionPhase maxPhase) {
3691 super(referenceTree, names.init, site, argtypes, typeargtypes, maxPhase);
3692 }
3693
3694 @Override
3695 protected Symbol lookup(Env<AttrContext> env, MethodResolutionPhase phase) {
3696 WriteableScope sc = WriteableScope.create(syms.arrayClass);
3697 MethodSymbol arrayConstr = new MethodSymbol(PUBLIC, name, null, site.tsym);
3698 arrayConstr.type = new MethodType(List.of(syms.intType), site, List.nil(), syms.methodClass);
3699 sc.enter(arrayConstr);
3700 return findMethodInScope(env, site, name, argtypes, typeargtypes, sc, methodNotFound, phase.isBoxingRequired(), phase.isVarargsRequired(), false);
3701 }
3702
3703 @Override
3704 ReferenceKind referenceKind(Symbol sym) {
3705 return ReferenceKind.ARRAY_CTOR;
3706 }
3707 }
3708
3709 /**
3710 * Helper class for constructor reference lookup. The lookup logic is based
3711 * upon either Resolve.findMethod or Resolve.findDiamond - depending on
3712 * whether the constructor reference needs diamond inference (this is the case
3713 * if the qualifier type is raw). A special erroneous symbol is returned
3714 * if the lookup returns the constructor of an inner class and there's no
3715 * enclosing instance in scope.
3716 */
3717 class ConstructorReferenceLookupHelper extends ReferenceLookupHelper {
3718
3719 boolean needsInference;
3720
3721 ConstructorReferenceLookupHelper(JCMemberReference referenceTree, Type site, List<Type> argtypes,
3722 List<Type> typeargtypes, MethodResolutionPhase maxPhase) {
3723 super(referenceTree, names.init, site, argtypes, typeargtypes, maxPhase);
3724 if (site.isRaw()) {
3725 this.site = new ClassType(site.getEnclosingType(),
3726 !(site.tsym.isInner() && site.getEnclosingType().isRaw()) ?
3727 site.tsym.type.getTypeArguments() : List.nil(), site.tsym, site.getMetadata());
3728 needsInference = true;
3729 }
3730 }
3731
3732 @Override
3733 protected Symbol lookup(Env<AttrContext> env, MethodResolutionPhase phase) {
3734 Symbol sym = needsInference ?
3735 findDiamond(env, site, argtypes, typeargtypes, phase.isBoxingRequired(), phase.isVarargsRequired()) :
3736 findMethod(env, site, name, argtypes, typeargtypes,
3737 phase.isBoxingRequired(), phase.isVarargsRequired());
3738 return enclosingInstanceMissing(env, site) ? new BadConstructorReferenceError(sym) : sym;
3739 }
3740
3741 @Override
3742 ReferenceKind referenceKind(Symbol sym) {
3743 return site.getEnclosingType().hasTag(NONE) ?
3744 ReferenceKind.TOPLEVEL : ReferenceKind.IMPLICIT_INNER;
3745 }
3746 }
3747
3748 /**
3749 * Main overload resolution routine. On each overload resolution step, a
3750 * lookup helper class is used to perform the method/constructor lookup;
3751 * at the end of the lookup, the helper is used to validate the results
3752 * (this last step might trigger overload resolution diagnostics).
3753 */
3754 Symbol lookupMethod(Env<AttrContext> env, DiagnosticPosition pos, Symbol location, MethodCheck methodCheck, LookupHelper lookupHelper) {
3755 MethodResolutionContext resolveContext = new MethodResolutionContext();
3756 resolveContext.methodCheck = methodCheck;
3757 return lookupMethod(env, pos, location, resolveContext, lookupHelper);
3758 }
3759
3760 Symbol lookupMethod(Env<AttrContext> env, DiagnosticPosition pos, Symbol location,
3761 MethodResolutionContext resolveContext, LookupHelper lookupHelper) {
3762 MethodResolutionContext prevResolutionContext = currentResolutionContext;
3763 try {
3764 Symbol bestSoFar = methodNotFound;
3765 currentResolutionContext = resolveContext;
3766 for (MethodResolutionPhase phase : methodResolutionSteps) {
3767 if (lookupHelper.shouldStop(bestSoFar, phase))
3768 break;
3769 MethodResolutionPhase prevPhase = currentResolutionContext.step;
3770 Symbol prevBest = bestSoFar;
3771 currentResolutionContext.step = phase;
3772 Symbol sym = lookupHelper.lookup(env, phase);
3773 lookupHelper.debug(pos, sym);
3774 bestSoFar = phase.mergeResults(bestSoFar, sym);
3775 env.info.pendingResolutionPhase = (prevBest == bestSoFar) ? prevPhase : phase;
3776 }
3777 return lookupHelper.access(env, pos, location, bestSoFar);
3778 } finally {
3779 currentResolutionContext = prevResolutionContext;
3780 }
3781 }
3782
3783 /**
3784 * Resolve `c.name' where name == this or name == super.
3785 * @param pos The position to use for error reporting.
3786 * @param env The environment current at the expression.
3787 * @param c The qualifier.
3788 * @param name The identifier's name.
3789 */
3790 Symbol resolveSelf(DiagnosticPosition pos,
3791 Env<AttrContext> env,
3792 TypeSymbol c,
3793 Name name) {
3794 Assert.check(name == names._this || name == names._super);
3795 Env<AttrContext> env1 = env;
3796 boolean staticOnly = false;
3797 while (env1.outer != null) {
3798 if (isStatic(env1)) staticOnly = true;
3799 if (env1.enclClass.sym == c) {
3800 Symbol sym = env1.info.scope.findFirst(name);
3801 if (sym != null) {
3802 if (staticOnly)
3803 sym = new StaticError(sym);
3804 else if (env1.info.ctorPrologue && !isAllowedEarlyReference(pos, env1, (VarSymbol)sym))
3805 sym = new RefBeforeCtorCalledError(sym);
3806 return accessBase(sym, pos, env.enclClass.sym.type,
3807 name, true);
3808 }
3809 }
3810 if ((env1.enclClass.sym.flags() & STATIC) != 0) staticOnly = true;
3811 env1 = env1.outer;
3812 }
3813 if (c.isInterface() &&
3814 name == names._super && !isStatic(env) &&
3815 types.isDirectSuperInterface(c, env.enclClass.sym)) {
3816 //this might be a default super call if one of the superinterfaces is 'c'
3817 for (Type t : pruneInterfaces(env.enclClass.type)) {
3818 if (t.tsym == c) {
3819 if (env.info.ctorPrologue)
3820 log.error(pos, Errors.CantRefBeforeCtorCalled(name));
3821 env.info.defaultSuperCallSite = t;
3822 return new VarSymbol(0, names._super,
3823 types.asSuper(env.enclClass.type, c), env.enclClass.sym);
3824 }
3825 }
3826 //find a direct supertype that is a subtype of 'c'
3827 for (Type i : types.directSupertypes(env.enclClass.type)) {
3828 if (i.tsym.isSubClass(c, types) && i.tsym != c) {
3829 log.error(pos,
3830 Errors.IllegalDefaultSuperCall(c,
3831 Fragments.RedundantSupertype(c, i)));
3832 return syms.errSymbol;
3833 }
3834 }
3835 Assert.error();
3836 }
3837 log.error(pos, Errors.NotEnclClass(c));
3838 return syms.errSymbol;
3839 }
3840 //where
3841 private List<Type> pruneInterfaces(Type t) {
3842 ListBuffer<Type> result = new ListBuffer<>();
3843 for (Type t1 : types.interfaces(t)) {
3844 boolean shouldAdd = true;
3845 for (Type t2 : types.directSupertypes(t)) {
3846 if (t1 != t2 && !t2.hasTag(ERROR) && types.isSubtypeNoCapture(t2, t1)) {
3847 shouldAdd = false;
3848 }
3849 }
3850 if (shouldAdd) {
3851 result.append(t1);
3852 }
3853 }
3854 return result.toList();
3855 }
3856
3857 /**
3858 * Determine if an early instance field reference may appear in a constructor prologue.
3859 *
3860 * <p>
3861 * This is only allowed when:
3862 * - The field is being assigned a value (i.e., written but not read)
3863 * - The field is not inherited from a superclass
3864 * - The assignment is not within a lambda, because that would require
3865 * capturing 'this' which is not allowed prior to super().
3866 *
3867 * <p>
3868 * Note, this method doesn't catch all such scenarios, because this method
3869 * is invoked for symbol "x" only for "x = 42" but not for "this.x = 42".
3870 * We also don't verify that the field has no initializer, which is required.
3871 * To catch those cases, we rely on similar logic in Attr.checkAssignable().
3872 */
3873 private boolean isAllowedEarlyReference(DiagnosticPosition pos, Env<AttrContext> env, VarSymbol v) {
3874
3875 // Check assumptions
3876 Assert.check(env.info.ctorPrologue);
3877 Assert.check((v.flags_field & STATIC) == 0);
3878
3879 // The symbol must appear in the LHS of an assignment statement
3880 if (!(env.tree instanceof JCAssign assign))
3881 return false;
3882
3883 // The assignment statement must not be within a lambda
3884 if (env.info.isLambda)
3885 return false;
3886
3887 // Get the symbol's qualifier, if any
3888 JCExpression lhs = TreeInfo.skipParens(assign.lhs);
3889 JCExpression base;
3890 switch (lhs.getTag()) {
3891 case IDENT:
3892 base = null;
3893 break;
3894 case SELECT:
3895 JCFieldAccess select = (JCFieldAccess)lhs;
3896 base = select.selected;
3897 if (!TreeInfo.isExplicitThisReference(types, (ClassType)env.enclClass.type, base))
3898 return false;
3899 break;
3900 default:
3901 return false;
3902 }
3903
3904 // If an early reference, the field must not be declared in a superclass
3905 if (isEarlyReference(env, base, v) && v.owner != env.enclClass.sym)
3906 return false;
3907
3908 // The flexible constructors feature must be enabled
3909 preview.checkSourceLevel(pos, Feature.FLEXIBLE_CONSTRUCTORS);
3910
3911 // OK
3912 return true;
3913 }
3914
3915 /**
3916 * Determine if the variable appearance constitutes an early reference to the current class.
3917 *
3918 * <p>
3919 * This means the variable is an instance field of the current class and it appears
3920 * in an early initialization context of it (i.e., one of its constructor prologues).
3921 *
3922 * <p>
3923 * Such a reference is only allowed for assignments to non-initialized fields that are
3924 * not inherited from a superclass, though that is not enforced by this method.
3925 *
3926 * @param env The current environment
3927 * @param base Variable qualifier, if any, otherwise null
3928 * @param v The variable
3929 */
3930 public boolean isEarlyReference(Env<AttrContext> env, JCTree base, VarSymbol v) {
3931 return env.info.ctorPrologue &&
3932 (v.flags() & STATIC) == 0 &&
3933 v.owner.kind == TYP &&
3934 types.isSubtype(env.enclClass.type, v.owner.type) &&
3935 (base == null || TreeInfo.isExplicitThisReference(types, (ClassType)env.enclClass.type, base));
3936 }
3937
3938 /**
3939 * Resolve `c.this' for an enclosing class c that contains the
3940 * named member.
3941 * @param pos The position to use for error reporting.
3942 * @param env The environment current at the expression.
3943 * @param member The member that must be contained in the result.
3944 */
3945 Symbol resolveSelfContaining(DiagnosticPosition pos,
3946 Env<AttrContext> env,
3947 Symbol member,
3948 boolean isSuperCall) {
3949 Symbol sym = resolveSelfContainingInternal(env, member, isSuperCall);
3950 if (sym == null) {
3951 log.error(pos, Errors.EnclClassRequired(member));
3952 return syms.errSymbol;
3953 } else {
3954 return accessBase(sym, pos, env.enclClass.sym.type, sym.name, true);
3955 }
3956 }
3957
3958 boolean enclosingInstanceMissing(Env<AttrContext> env, Type type) {
3959 if (type.hasTag(CLASS) && type.getEnclosingType().hasTag(CLASS)) {
3960 Symbol encl = resolveSelfContainingInternal(env, type.tsym, false);
3961 return encl == null || encl.kind.isResolutionError();
3962 }
3963 return false;
3964 }
3965
3966 private Symbol resolveSelfContainingInternal(Env<AttrContext> env,
3967 Symbol member,
3968 boolean isSuperCall) {
3969 Name name = names._this;
3970 Env<AttrContext> env1 = isSuperCall ? env.outer : env;
3971 boolean staticOnly = false;
3972 if (env1 != null) {
3973 while (env1 != null && env1.outer != null) {
3974 if (isStatic(env1)) staticOnly = true;
3975 if (env1.enclClass.sym.isSubClass(member.owner.enclClass(), types)) {
3976 Symbol sym = env1.info.scope.findFirst(name);
3977 if (sym != null) {
3978 if (staticOnly) sym = new StaticError(sym);
3979 return sym;
3980 }
3981 }
3982 if ((env1.enclClass.sym.flags() & STATIC) != 0)
3983 staticOnly = true;
3984 env1 = env1.outer;
3985 }
3986 }
3987 return null;
3988 }
3989
3990 /**
3991 * Resolve an appropriate implicit this instance for t's container.
3992 * JLS 8.8.5.1 and 15.9.2
3993 */
3994 Type resolveImplicitThis(DiagnosticPosition pos, Env<AttrContext> env, Type t) {
3995 return resolveImplicitThis(pos, env, t, false);
3996 }
3997
3998 Type resolveImplicitThis(DiagnosticPosition pos, Env<AttrContext> env, Type t, boolean isSuperCall) {
3999 Type thisType = (t.tsym.owner.kind.matches(KindSelector.VAL_MTH)
4000 ? resolveSelf(pos, env, t.getEnclosingType().tsym, names._this)
4001 : resolveSelfContaining(pos, env, t.tsym, isSuperCall)).type;
4002 if (env.info.ctorPrologue && thisType.tsym == env.enclClass.sym) {
4003 log.error(pos, Errors.CantRefBeforeCtorCalled(names._this));
4004 }
4005 return thisType;
4006 }
4007
4008 /* ***************************************************************************
4009 * ResolveError classes, indicating error situations when accessing symbols
4010 ****************************************************************************/
4011
4012 //used by TransTypes when checking target type of synthetic cast
4013 public void logAccessErrorInternal(Env<AttrContext> env, JCTree tree, Type type) {
4014 AccessError error = new AccessError(env, env.enclClass.type, type.tsym);
4015 logResolveError(error, tree.pos(), env.enclClass.sym, env.enclClass.type, null, null, null);
4016 }
4017 //where
4018 private void logResolveError(ResolveError error,
4019 DiagnosticPosition pos,
4020 Symbol location,
4021 Type site,
4022 Name name,
4023 List<Type> argtypes,
4024 List<Type> typeargtypes) {
4025 JCDiagnostic d = error.getDiagnostic(JCDiagnostic.DiagnosticType.ERROR,
4026 pos, location, site, name, argtypes, typeargtypes);
4027 if (d != null) {
4028 d.setFlag(DiagnosticFlag.RESOLVE_ERROR);
4029 log.report(d);
4030 }
4031 }
4032
4033 private final LocalizedString noArgs = new LocalizedString("compiler.misc.no.args");
4034
4035 public Object methodArguments(List<Type> argtypes) {
4036 if (argtypes == null || argtypes.isEmpty()) {
4037 return noArgs;
4038 } else {
4039 ListBuffer<Object> diagArgs = new ListBuffer<>();
4040 for (Type t : argtypes) {
4041 if (t.hasTag(DEFERRED)) {
4042 diagArgs.append(((DeferredAttr.DeferredType)t).tree);
4043 } else {
4044 diagArgs.append(t);
4045 }
4046 }
4047 return diagArgs;
4048 }
4049 }
4050
4051 /** check if a type is a subtype of Serializable, if that is available.*/
4052 boolean isSerializable(Type t) {
4053 try {
4054 syms.serializableType.complete();
4055 }
4056 catch (CompletionFailure e) {
4057 return false;
4058 }
4059 return types.isSubtype(t, syms.serializableType);
4060 }
4061
4062 /**
4063 * Root class for resolution errors. Subclass of ResolveError
4064 * represent a different kinds of resolution error - as such they must
4065 * specify how they map into concrete compiler diagnostics.
4066 */
4067 abstract class ResolveError extends Symbol {
4068
4069 /** The name of the kind of error, for debugging only. */
4070 final String debugName;
4071
4072 ResolveError(Kind kind, String debugName) {
4073 super(kind, 0, null, null, null);
4074 this.debugName = debugName;
4075 }
4076
4077 @Override @DefinedBy(Api.LANGUAGE_MODEL)
4078 public <R, P> R accept(ElementVisitor<R, P> v, P p) {
4079 throw new AssertionError();
4080 }
4081
4082 @Override
4083 public String toString() {
4084 return debugName;
4085 }
4086
4087 @Override
4088 public boolean exists() {
4089 return false;
4090 }
4091
4092 @Override
4093 public boolean isStatic() {
4094 return false;
4095 }
4096
4097 /**
4098 * Create an external representation for this erroneous symbol to be
4099 * used during attribution - by default this returns the symbol of a
4100 * brand new error type which stores the original type found
4101 * during resolution.
4102 *
4103 * @param name the name used during resolution
4104 * @param location the location from which the symbol is accessed
4105 */
4106 protected Symbol access(Name name, TypeSymbol location) {
4107 return types.createErrorType(name, location, syms.errSymbol.type).tsym;
4108 }
4109
4110 /**
4111 * Create a diagnostic representing this resolution error.
4112 *
4113 * @param dkind The kind of the diagnostic to be created (e.g error).
4114 * @param pos The position to be used for error reporting.
4115 * @param site The original type from where the selection took place.
4116 * @param name The name of the symbol to be resolved.
4117 * @param argtypes The invocation's value arguments,
4118 * if we looked for a method.
4119 * @param typeargtypes The invocation's type arguments,
4120 * if we looked for a method.
4121 */
4122 abstract JCDiagnostic getDiagnostic(JCDiagnostic.DiagnosticType dkind,
4123 DiagnosticPosition pos,
4124 Symbol location,
4125 Type site,
4126 Name name,
4127 List<Type> argtypes,
4128 List<Type> typeargtypes);
4129 }
4130
4131 /**
4132 * This class is the root class of all resolution errors caused by
4133 * an invalid symbol being found during resolution.
4134 */
4135 abstract class InvalidSymbolError extends ResolveError {
4136
4137 /** The invalid symbol found during resolution */
4138 Symbol sym;
4139
4140 InvalidSymbolError(Kind kind, Symbol sym, String debugName) {
4141 super(kind, debugName);
4142 this.sym = sym;
4143 }
4144
4145 @Override
4146 public boolean exists() {
4147 return true;
4148 }
4149
4150 @Override
4151 public String toString() {
4152 return super.toString() + " wrongSym=" + sym;
4153 }
4154
4155 @Override
4156 public Symbol access(Name name, TypeSymbol location) {
4157 if (!sym.kind.isResolutionError() && sym.kind.matches(KindSelector.TYP))
4158 return types.createErrorType(name, location, sym.type).tsym;
4159 else
4160 return sym;
4161 }
4162 }
4163
4164 class BadRestrictedTypeError extends ResolveError {
4165 private final Name typeName;
4166 BadRestrictedTypeError(Name typeName) {
4167 super(Kind.BAD_RESTRICTED_TYPE, "bad var use");
4168 this.typeName = typeName;
4169 }
4170
4171 @Override
4172 JCDiagnostic getDiagnostic(DiagnosticType dkind, DiagnosticPosition pos, Symbol location, Type site, Name name, List<Type> argtypes, List<Type> typeargtypes) {
4173 return diags.create(dkind, log.currentSource(), pos, "illegal.ref.to.restricted.type", typeName);
4174 }
4175 }
4176
4177 /**
4178 * InvalidSymbolError error class indicating that a symbol matching a
4179 * given name does not exists in a given site.
4180 */
4181 class SymbolNotFoundError extends ResolveError {
4182
4183 SymbolNotFoundError(Kind kind) {
4184 this(kind, "symbol not found error");
4185 }
4186
4187 SymbolNotFoundError(Kind kind, String debugName) {
4188 super(kind, debugName);
4189 }
4190
4191 @Override
4192 JCDiagnostic getDiagnostic(JCDiagnostic.DiagnosticType dkind,
4193 DiagnosticPosition pos,
4194 Symbol location,
4195 Type site,
4196 Name name,
4197 List<Type> argtypes,
4198 List<Type> typeargtypes) {
4199 argtypes = argtypes == null ? List.nil() : argtypes;
4200 typeargtypes = typeargtypes == null ? List.nil() : typeargtypes;
4201 if (name == names.error)
4202 return null;
4203
4204 boolean hasLocation = false;
4205 if (location == null) {
4206 location = site.tsym;
4207 }
4208 if (!location.name.isEmpty()) {
4209 if (location.kind == PCK && !site.tsym.exists() && location.name != names.java) {
4210 return diags.create(dkind, log.currentSource(), pos,
4211 "doesnt.exist", location);
4212 }
4213 hasLocation = !location.name.equals(names._this) &&
4214 !location.name.equals(names._super);
4215 }
4216 boolean isConstructor = name == names.init;
4217 KindName kindname = isConstructor ? KindName.CONSTRUCTOR : kind.absentKind();
4218 Name idname = isConstructor ? site.tsym.name : name;
4219 String errKey = getErrorKey(kindname, typeargtypes.nonEmpty(), hasLocation);
4220 if (hasLocation) {
4221 return diags.create(dkind, log.currentSource(), pos,
4222 errKey, kindname, idname, //symbol kindname, name
4223 typeargtypes, args(argtypes), //type parameters and arguments (if any)
4224 getLocationDiag(location, site)); //location kindname, type
4225 }
4226 else {
4227 return diags.create(dkind, log.currentSource(), pos,
4228 errKey, kindname, idname, //symbol kindname, name
4229 typeargtypes, args(argtypes)); //type parameters and arguments (if any)
4230 }
4231 }
4232 //where
4233 private Object args(List<Type> args) {
4234 return args.isEmpty() ? args : methodArguments(args);
4235 }
4236
4237 private String getErrorKey(KindName kindname, boolean hasTypeArgs, boolean hasLocation) {
4238 String key = "cant.resolve";
4239 String suffix = hasLocation ? ".location" : "";
4240 switch (kindname) {
4241 case METHOD:
4242 case CONSTRUCTOR: {
4243 suffix += ".args";
4244 suffix += hasTypeArgs ? ".params" : "";
4245 }
4246 }
4247 return key + suffix;
4248 }
4249 private JCDiagnostic getLocationDiag(Symbol location, Type site) {
4250 if (location.kind == VAR) {
4251 return diags.fragment(Fragments.Location1(kindName(location),
4252 location,
4253 location.type));
4254 } else {
4255 return diags.fragment(Fragments.Location(typeKindName(site),
4256 site,
4257 null));
4258 }
4259 }
4260 }
4261
4262 /**
4263 * InvalidSymbolError error class indicating that a given symbol
4264 * (either a method, a constructor or an operand) is not applicable
4265 * given an actual arguments/type argument list.
4266 */
4267 class InapplicableSymbolError extends ResolveError {
4268
4269 protected MethodResolutionContext resolveContext;
4270
4271 InapplicableSymbolError(MethodResolutionContext context) {
4272 this(WRONG_MTH, "inapplicable symbol error", context);
4273 }
4274
4275 protected InapplicableSymbolError(Kind kind, String debugName, MethodResolutionContext context) {
4276 super(kind, debugName);
4277 this.resolveContext = context;
4278 }
4279
4280 @Override
4281 public String toString() {
4282 return super.toString();
4283 }
4284
4285 @Override
4286 public boolean exists() {
4287 return true;
4288 }
4289
4290 @Override
4291 JCDiagnostic getDiagnostic(JCDiagnostic.DiagnosticType dkind,
4292 DiagnosticPosition pos,
4293 Symbol location,
4294 Type site,
4295 Name name,
4296 List<Type> argtypes,
4297 List<Type> typeargtypes) {
4298 if (name == names.error)
4299 return null;
4300
4301 Pair<Symbol, JCDiagnostic> c = errCandidate();
4302 Symbol ws = c.fst.asMemberOf(site, types);
4303 UnaryOperator<JCDiagnostic> rewriter = compactMethodDiags ?
4304 d -> MethodResolutionDiagHelper.rewrite(diags, pos, log.currentSource(), dkind, c.snd) : null;
4305
4306 // If the problem is due to type arguments, then the method parameters aren't relevant,
4307 // so use the error message that omits them to avoid confusion.
4308 switch (c.snd.getCode()) {
4309 case "compiler.misc.wrong.number.type.args":
4310 case "compiler.misc.explicit.param.do.not.conform.to.bounds":
4311 return diags.create(dkind, log.currentSource(), pos,
4312 "cant.apply.symbol.noargs",
4313 rewriter,
4314 kindName(ws),
4315 ws.name == names.init ? ws.owner.name : ws.name,
4316 kindName(ws.owner),
4317 ws.owner.type,
4318 c.snd);
4319 default:
4320 // Avoid saying "constructor Array in class Array"
4321 if (ws.owner == syms.arrayClass && ws.name == names.init) {
4322 return diags.create(dkind, log.currentSource(), pos,
4323 "cant.apply.array.ctor",
4324 rewriter,
4325 methodArguments(ws.type.getParameterTypes()),
4326 methodArguments(argtypes),
4327 c.snd);
4328 }
4329 return diags.create(dkind, log.currentSource(), pos,
4330 "cant.apply.symbol",
4331 rewriter,
4332 kindName(ws),
4333 ws.name == names.init ? ws.owner.name : ws.name,
4334 methodArguments(ws.type.getParameterTypes()),
4335 methodArguments(argtypes),
4336 kindName(ws.owner),
4337 ws.owner.type,
4338 c.snd);
4339 }
4340 }
4341
4342 @Override
4343 public Symbol access(Name name, TypeSymbol location) {
4344 Pair<Symbol, JCDiagnostic> cand = errCandidate();
4345 TypeSymbol errSymbol = types.createErrorType(name, location, cand != null ? cand.fst.type : syms.errSymbol.type).tsym;
4346 if (cand != null) {
4347 attrRecover.wrongMethodSymbolCandidate(errSymbol, cand.fst, cand.snd);
4348 }
4349 return errSymbol;
4350 }
4351
4352 protected Pair<Symbol, JCDiagnostic> errCandidate() {
4353 Candidate bestSoFar = null;
4354 for (Candidate c : resolveContext.candidates) {
4355 if (c.isApplicable()) continue;
4356 bestSoFar = c;
4357 }
4358 Assert.checkNonNull(bestSoFar);
4359 return new Pair<>(bestSoFar.sym, bestSoFar.details);
4360 }
4361 }
4362
4363 /**
4364 * ResolveError error class indicating that a symbol (either methods, constructors or operand)
4365 * is not applicable given an actual arguments/type argument list.
4366 */
4367 class InapplicableSymbolsError extends InapplicableSymbolError {
4368
4369 InapplicableSymbolsError(MethodResolutionContext context) {
4370 super(WRONG_MTHS, "inapplicable symbols", context);
4371 }
4372
4373 @Override
4374 JCDiagnostic getDiagnostic(JCDiagnostic.DiagnosticType dkind,
4375 DiagnosticPosition pos,
4376 Symbol location,
4377 Type site,
4378 Name name,
4379 List<Type> argtypes,
4380 List<Type> typeargtypes) {
4381 Map<Symbol, JCDiagnostic> candidatesMap = mapCandidates();
4382 Map<Symbol, JCDiagnostic> filteredCandidates = compactMethodDiags ?
4383 filterCandidates(candidatesMap) :
4384 mapCandidates();
4385 if (filteredCandidates.isEmpty()) {
4386 filteredCandidates = candidatesMap;
4387 }
4388 boolean truncatedDiag = candidatesMap.size() != filteredCandidates.size();
4389 if (filteredCandidates.size() > 1) {
4390 JCDiagnostic err = diags.create(dkind,
4391 null,
4392 truncatedDiag ?
4393 EnumSet.of(DiagnosticFlag.COMPRESSED) :
4394 EnumSet.noneOf(DiagnosticFlag.class),
4395 log.currentSource(),
4396 pos,
4397 "cant.apply.symbols",
4398 name == names.init ? KindName.CONSTRUCTOR : kind.absentKind(),
4399 name == names.init ? site.tsym.name : name,
4400 methodArguments(argtypes));
4401 return new JCDiagnostic.MultilineDiagnostic(err, candidateDetails(filteredCandidates, site));
4402 } else if (filteredCandidates.size() == 1) {
4403 Map.Entry<Symbol, JCDiagnostic> _e =
4404 filteredCandidates.entrySet().iterator().next();
4405 final Pair<Symbol, JCDiagnostic> p = new Pair<>(_e.getKey(), _e.getValue());
4406 JCDiagnostic d = new InapplicableSymbolError(resolveContext) {
4407 @Override
4408 protected Pair<Symbol, JCDiagnostic> errCandidate() {
4409 return p;
4410 }
4411 }.getDiagnostic(dkind, pos,
4412 location, site, name, argtypes, typeargtypes);
4413 if (truncatedDiag) {
4414 d.setFlag(DiagnosticFlag.COMPRESSED);
4415 }
4416 return d;
4417 } else {
4418 return new SymbolNotFoundError(ABSENT_MTH).getDiagnostic(dkind, pos,
4419 location, site, name, argtypes, typeargtypes);
4420 }
4421 }
4422 //where
4423 private Map<Symbol, JCDiagnostic> mapCandidates() {
4424 MostSpecificMap candidates = new MostSpecificMap();
4425 for (Candidate c : resolveContext.candidates) {
4426 if (c.isApplicable()) continue;
4427 candidates.put(c);
4428 }
4429 return candidates;
4430 }
4431
4432 @SuppressWarnings("serial")
4433 private class MostSpecificMap extends LinkedHashMap<Symbol, JCDiagnostic> {
4434 private void put(Candidate c) {
4435 ListBuffer<Symbol> overridden = new ListBuffer<>();
4436 for (Symbol s : keySet()) {
4437 if (s == c.sym) {
4438 continue;
4439 }
4440 if (c.sym.overrides(s, (TypeSymbol)s.owner, types, false)) {
4441 overridden.add(s);
4442 } else if (s.overrides(c.sym, (TypeSymbol)c.sym.owner, types, false)) {
4443 return;
4444 }
4445 }
4446 for (Symbol s : overridden) {
4447 remove(s);
4448 }
4449 put(c.sym, c.details);
4450 }
4451 }
4452
4453 Map<Symbol, JCDiagnostic> filterCandidates(Map<Symbol, JCDiagnostic> candidatesMap) {
4454 Map<Symbol, JCDiagnostic> candidates = new LinkedHashMap<>();
4455 for (Map.Entry<Symbol, JCDiagnostic> _entry : candidatesMap.entrySet()) {
4456 JCDiagnostic d = _entry.getValue();
4457 if (!new Template(MethodCheckDiag.ARITY_MISMATCH.regex()).matches(d)) {
4458 candidates.put(_entry.getKey(), d);
4459 }
4460 }
4461 return candidates;
4462 }
4463
4464 private List<JCDiagnostic> candidateDetails(Map<Symbol, JCDiagnostic> candidatesMap, Type site) {
4465 List<JCDiagnostic> details = List.nil();
4466 for (Map.Entry<Symbol, JCDiagnostic> _entry : candidatesMap.entrySet()) {
4467 Symbol sym = _entry.getKey();
4468 JCDiagnostic detailDiag =
4469 diags.fragment(Fragments.InapplicableMethod(Kinds.kindName(sym),
4470 sym.location(site, types),
4471 sym.asMemberOf(site, types),
4472 _entry.getValue()));
4473 details = details.prepend(detailDiag);
4474 }
4475 //typically members are visited in reverse order (see Scope)
4476 //so we need to reverse the candidate list so that candidates
4477 //conform to source order
4478 return details;
4479 }
4480
4481 @Override
4482 protected Pair<Symbol, JCDiagnostic> errCandidate() {
4483 Map<Symbol, JCDiagnostic> candidatesMap = mapCandidates();
4484 Map<Symbol, JCDiagnostic> filteredCandidates = filterCandidates(candidatesMap);
4485 if (filteredCandidates.size() == 1) {
4486 return Pair.of(filteredCandidates.keySet().iterator().next(),
4487 filteredCandidates.values().iterator().next());
4488 }
4489 return null;
4490 }
4491 }
4492
4493 /**
4494 * DiamondError error class indicating that a constructor symbol is not applicable
4495 * given an actual arguments/type argument list using diamond inference.
4496 */
4497 class DiamondError extends InapplicableSymbolError {
4498
4499 Symbol sym;
4500
4501 public DiamondError(Symbol sym, MethodResolutionContext context) {
4502 super(sym.kind, "diamondError", context);
4503 this.sym = sym;
4504 }
4505
4506 JCDiagnostic getDetails() {
4507 return (sym.kind == WRONG_MTH) ?
4508 ((InapplicableSymbolError)sym.baseSymbol()).errCandidate().snd :
4509 null;
4510 }
4511
4512 @Override
4513 JCDiagnostic getDiagnostic(DiagnosticType dkind, DiagnosticPosition pos,
4514 Symbol location, Type site, Name name, List<Type> argtypes, List<Type> typeargtypes) {
4515 JCDiagnostic details = getDetails();
4516 if (details != null && compactMethodDiags) {
4517 JCDiagnostic simpleDiag =
4518 MethodResolutionDiagHelper.rewrite(diags, pos, log.currentSource(), dkind, details);
4519 if (simpleDiag != null) {
4520 return simpleDiag;
4521 }
4522 }
4523 String key = details == null ?
4524 "cant.apply.diamond" :
4525 "cant.apply.diamond.1";
4526 return diags.create(dkind, log.currentSource(), pos, key,
4527 Fragments.Diamond(site.tsym), details);
4528 }
4529 }
4530
4531 /**
4532 * An InvalidSymbolError error class indicating that a symbol is not
4533 * accessible from a given site
4534 */
4535 class AccessError extends InvalidSymbolError {
4536
4537 private Env<AttrContext> env;
4538 private Type site;
4539
4540 AccessError(Env<AttrContext> env, Type site, Symbol sym) {
4541 super(HIDDEN, sym, "access error");
4542 this.env = env;
4543 this.site = site;
4544 }
4545
4546 @Override
4547 public boolean exists() {
4548 return false;
4549 }
4550
4551 @Override
4552 JCDiagnostic getDiagnostic(JCDiagnostic.DiagnosticType dkind,
4553 DiagnosticPosition pos,
4554 Symbol location,
4555 Type site,
4556 Name name,
4557 List<Type> argtypes,
4558 List<Type> typeargtypes) {
4559 if (sym.name == names.init && sym.owner != site.tsym) {
4560 return new SymbolNotFoundError(ABSENT_MTH).getDiagnostic(dkind,
4561 pos, location, site, name, argtypes, typeargtypes);
4562 }
4563 else if ((sym.flags() & PUBLIC) != 0
4564 || (env != null && this.site != null
4565 && !isAccessible(env, this.site))) {
4566 if (sym.owner.kind == PCK) {
4567 return diags.create(dkind, log.currentSource(),
4568 pos, "not.def.access.package.cant.access",
4569 sym, sym.location(), inaccessiblePackageReason(env, sym.packge()));
4570 } else if ( sym.packge() != syms.rootPackage
4571 && !symbolPackageVisible(env, sym)) {
4572 return diags.create(dkind, log.currentSource(),
4573 pos, "not.def.access.class.intf.cant.access.reason",
4574 sym, sym.location(), sym.location().packge(),
4575 inaccessiblePackageReason(env, sym.packge()));
4576 } else {
4577 return diags.create(dkind, log.currentSource(),
4578 pos, "not.def.access.class.intf.cant.access",
4579 sym, sym.location());
4580 }
4581 }
4582 else if ((sym.flags() & (PRIVATE | PROTECTED)) != 0) {
4583 return diags.create(dkind, log.currentSource(),
4584 pos, "report.access", sym,
4585 asFlagSet(sym.flags() & (PRIVATE | PROTECTED)),
4586 sym.location());
4587 }
4588 else {
4589 return diags.create(dkind, log.currentSource(),
4590 pos, "not.def.public.cant.access", sym, sym.location());
4591 }
4592 }
4593
4594 private String toString(Type type) {
4595 StringBuilder sb = new StringBuilder();
4596 sb.append(type);
4597 if (type != null) {
4598 sb.append("[tsym:").append(type.tsym);
4599 if (type.tsym != null)
4600 sb.append("packge:").append(type.tsym.packge());
4601 sb.append("]");
4602 }
4603 return sb.toString();
4604 }
4605 }
4606
4607 class InvisibleSymbolError extends InvalidSymbolError {
4608
4609 private final Env<AttrContext> env;
4610 private final boolean suppressError;
4611
4612 InvisibleSymbolError(Env<AttrContext> env, boolean suppressError, Symbol sym) {
4613 super(HIDDEN, sym, "invisible class error");
4614 this.env = env;
4615 this.suppressError = suppressError;
4616 this.name = sym.name;
4617 }
4618
4619 @Override
4620 JCDiagnostic getDiagnostic(JCDiagnostic.DiagnosticType dkind,
4621 DiagnosticPosition pos,
4622 Symbol location,
4623 Type site,
4624 Name name,
4625 List<Type> argtypes,
4626 List<Type> typeargtypes) {
4627 if (suppressError)
4628 return null;
4629
4630 if (sym.kind == PCK) {
4631 JCDiagnostic details = inaccessiblePackageReason(env, sym.packge());
4632 return diags.create(dkind, log.currentSource(),
4633 pos, "package.not.visible", sym, details);
4634 }
4635
4636 JCDiagnostic details = inaccessiblePackageReason(env, sym.packge());
4637
4638 if (pos.getTree() != null) {
4639 Symbol o = sym;
4640 JCTree tree = pos.getTree();
4641
4642 while (o.kind != PCK && tree.hasTag(SELECT)) {
4643 o = o.owner;
4644 tree = ((JCFieldAccess) tree).selected;
4645 }
4646
4647 if (o.kind == PCK) {
4648 pos = tree.pos();
4649
4650 return diags.create(dkind, log.currentSource(),
4651 pos, "package.not.visible", o, details);
4652 }
4653 }
4654
4655 return diags.create(dkind, log.currentSource(),
4656 pos, "not.def.access.package.cant.access", sym, sym.packge(), details);
4657 }
4658 }
4659
4660 JCDiagnostic inaccessiblePackageReason(Env<AttrContext> env, PackageSymbol sym) {
4661 //no dependency:
4662 if (!env.toplevel.modle.readModules.contains(sym.modle)) {
4663 //does not read:
4664 if (sym.modle != syms.unnamedModule) {
4665 if (env.toplevel.modle != syms.unnamedModule) {
4666 return diags.fragment(Fragments.NotDefAccessDoesNotRead(env.toplevel.modle,
4667 sym,
4668 sym.modle));
4669 } else {
4670 return diags.fragment(Fragments.NotDefAccessDoesNotReadFromUnnamed(sym,
4671 sym.modle));
4672 }
4673 } else {
4674 return diags.fragment(Fragments.NotDefAccessDoesNotReadUnnamed(sym,
4675 env.toplevel.modle));
4676 }
4677 } else {
4678 if (sym.packge().modle.exports.stream().anyMatch(e -> e.packge == sym)) {
4679 //not exported to this module:
4680 if (env.toplevel.modle != syms.unnamedModule) {
4681 return diags.fragment(Fragments.NotDefAccessNotExportedToModule(sym,
4682 sym.modle,
4683 env.toplevel.modle));
4684 } else {
4685 return diags.fragment(Fragments.NotDefAccessNotExportedToModuleFromUnnamed(sym,
4686 sym.modle));
4687 }
4688 } else {
4689 //not exported:
4690 if (env.toplevel.modle != syms.unnamedModule) {
4691 return diags.fragment(Fragments.NotDefAccessNotExported(sym,
4692 sym.modle));
4693 } else {
4694 return diags.fragment(Fragments.NotDefAccessNotExportedFromUnnamed(sym,
4695 sym.modle));
4696 }
4697 }
4698 }
4699 }
4700
4701 /**
4702 * InvalidSymbolError error class indicating that an instance member
4703 * has erroneously been accessed from a static context.
4704 */
4705 class StaticError extends InvalidSymbolError {
4706
4707 StaticError(Symbol sym) {
4708 this(sym, "static error");
4709 }
4710
4711 StaticError(Symbol sym, String debugName) {
4712 super(STATICERR, sym, debugName);
4713 }
4714
4715 @Override
4716 JCDiagnostic getDiagnostic(JCDiagnostic.DiagnosticType dkind,
4717 DiagnosticPosition pos,
4718 Symbol location,
4719 Type site,
4720 Name name,
4721 List<Type> argtypes,
4722 List<Type> typeargtypes) {
4723 Symbol errSym = ((sym.kind == TYP && sym.type.hasTag(CLASS))
4724 ? types.erasure(sym.type).tsym
4725 : sym);
4726 return diags.create(dkind, log.currentSource(), pos,
4727 "non-static.cant.be.ref", kindName(sym), errSym);
4728 }
4729 }
4730
4731 /**
4732 * Specialization of {@link InvalidSymbolError} for illegal
4733 * early accesses within a constructor prologue.
4734 */
4735 class RefBeforeCtorCalledError extends StaticError {
4736
4737 RefBeforeCtorCalledError(Symbol sym) {
4738 super(sym, "prologue error");
4739 }
4740
4741 @Override
4742 JCDiagnostic getDiagnostic(JCDiagnostic.DiagnosticType dkind,
4743 DiagnosticPosition pos,
4744 Symbol location,
4745 Type site,
4746 Name name,
4747 List<Type> argtypes,
4748 List<Type> typeargtypes) {
4749 Symbol errSym = ((sym.kind == TYP && sym.type.hasTag(CLASS))
4750 ? types.erasure(sym.type).tsym
4751 : sym);
4752 return diags.create(dkind, log.currentSource(), pos,
4753 "cant.ref.before.ctor.called", errSym);
4754 }
4755 }
4756
4757 /**
4758 * InvalidSymbolError error class indicating that a pair of symbols
4759 * (either methods, constructors or operands) are ambiguous
4760 * given an actual arguments/type argument list.
4761 */
4762 class AmbiguityError extends ResolveError {
4763
4764 /** The other maximally specific symbol */
4765 List<Symbol> ambiguousSyms = List.nil();
4766
4767 @Override
4768 public boolean exists() {
4769 return true;
4770 }
4771
4772 AmbiguityError(Symbol sym1, Symbol sym2) {
4773 super(AMBIGUOUS, "ambiguity error");
4774 ambiguousSyms = flatten(sym2).appendList(flatten(sym1));
4775 }
4776
4777 private List<Symbol> flatten(Symbol sym) {
4778 if (sym.kind == AMBIGUOUS) {
4779 return ((AmbiguityError)sym.baseSymbol()).ambiguousSyms;
4780 } else {
4781 return List.of(sym);
4782 }
4783 }
4784
4785 AmbiguityError addAmbiguousSymbol(Symbol s) {
4786 ambiguousSyms = ambiguousSyms.prepend(s);
4787 return this;
4788 }
4789
4790 @Override
4791 JCDiagnostic getDiagnostic(JCDiagnostic.DiagnosticType dkind,
4792 DiagnosticPosition pos,
4793 Symbol location,
4794 Type site,
4795 Name name,
4796 List<Type> argtypes,
4797 List<Type> typeargtypes) {
4798 List<Symbol> diagSyms = ambiguousSyms.reverse();
4799 Symbol s1 = diagSyms.head;
4800 Symbol s2 = diagSyms.tail.head;
4801 Name sname = s1.name;
4802 if (sname == names.init) sname = s1.owner.name;
4803 return diags.create(dkind, log.currentSource(),
4804 pos, "ref.ambiguous", sname,
4805 kindName(s1),
4806 s1,
4807 s1.location(site, types),
4808 kindName(s2),
4809 s2,
4810 s2.location(site, types));
4811 }
4812
4813 /**
4814 * If multiple applicable methods are found during overload and none of them
4815 * is more specific than the others, attempt to merge their signatures.
4816 */
4817 Symbol mergeAbstracts(Type site) {
4818 List<Symbol> ambiguousInOrder = ambiguousSyms.reverse();
4819 return types.mergeAbstracts(ambiguousInOrder, site, true).orElse(this);
4820 }
4821
4822 @Override
4823 protected Symbol access(Name name, TypeSymbol location) {
4824 Symbol firstAmbiguity = ambiguousSyms.last();
4825 return firstAmbiguity.kind == TYP ?
4826 types.createErrorType(name, location, firstAmbiguity.type).tsym :
4827 firstAmbiguity;
4828 }
4829 }
4830
4831 class BadVarargsMethod extends ResolveError {
4832
4833 ResolveError delegatedError;
4834
4835 BadVarargsMethod(ResolveError delegatedError) {
4836 super(delegatedError.kind, "badVarargs");
4837 this.delegatedError = delegatedError;
4838 }
4839
4840 @Override
4841 public Symbol baseSymbol() {
4842 return delegatedError.baseSymbol();
4843 }
4844
4845 @Override
4846 protected Symbol access(Name name, TypeSymbol location) {
4847 return delegatedError.access(name, location);
4848 }
4849
4850 @Override
4851 public boolean exists() {
4852 return true;
4853 }
4854
4855 @Override
4856 JCDiagnostic getDiagnostic(DiagnosticType dkind, DiagnosticPosition pos, Symbol location, Type site, Name name, List<Type> argtypes, List<Type> typeargtypes) {
4857 return delegatedError.getDiagnostic(dkind, pos, location, site, name, argtypes, typeargtypes);
4858 }
4859 }
4860
4861 /**
4862 * BadMethodReferenceError error class indicating that a method reference symbol has been found,
4863 * but with the wrong staticness.
4864 */
4865 class BadMethodReferenceError extends StaticError {
4866
4867 boolean unboundLookup;
4868
4869 public BadMethodReferenceError(Symbol sym, boolean unboundLookup) {
4870 super(sym, "bad method ref error");
4871 this.unboundLookup = unboundLookup;
4872 }
4873
4874 @Override
4875 JCDiagnostic getDiagnostic(DiagnosticType dkind, DiagnosticPosition pos, Symbol location, Type site, Name name, List<Type> argtypes, List<Type> typeargtypes) {
4876 final String key;
4877 if (!unboundLookup) {
4878 key = "bad.static.method.in.bound.lookup";
4879 } else if (sym.isStatic()) {
4880 key = "bad.static.method.in.unbound.lookup";
4881 } else {
4882 key = "bad.instance.method.in.unbound.lookup";
4883 }
4884 return sym.kind.isResolutionError() ?
4885 ((ResolveError)sym).getDiagnostic(dkind, pos, location, site, name, argtypes, typeargtypes) :
4886 diags.create(dkind, log.currentSource(), pos, key, Kinds.kindName(sym), sym);
4887 }
4888 }
4889
4890 /**
4891 * BadConstructorReferenceError error class indicating that a constructor reference symbol has been found,
4892 * but pointing to a class for which an enclosing instance is not available.
4893 */
4894 class BadConstructorReferenceError extends InvalidSymbolError {
4895
4896 public BadConstructorReferenceError(Symbol sym) {
4897 super(MISSING_ENCL, sym, "BadConstructorReferenceError");
4898 }
4899
4900 @Override
4901 JCDiagnostic getDiagnostic(DiagnosticType dkind, DiagnosticPosition pos, Symbol location, Type site, Name name, List<Type> argtypes, List<Type> typeargtypes) {
4902 return diags.create(dkind, log.currentSource(), pos,
4903 "cant.access.inner.cls.constr", site.tsym.name, argtypes, site.getEnclosingType());
4904 }
4905 }
4906
4907 class BadClassFileError extends InvalidSymbolError {
4908
4909 private final CompletionFailure ex;
4910
4911 public BadClassFileError(CompletionFailure ex) {
4912 super(HIDDEN, ex.sym, "BadClassFileError");
4913 this.name = sym.name;
4914 this.ex = ex;
4915 }
4916
4917 @Override
4918 JCDiagnostic getDiagnostic(DiagnosticType dkind, DiagnosticPosition pos, Symbol location, Type site, Name name, List<Type> argtypes, List<Type> typeargtypes) {
4919 JCDiagnostic d = diags.create(dkind, log.currentSource(), pos,
4920 "cant.access", ex.sym, ex.getDetailValue());
4921
4922 d.setFlag(DiagnosticFlag.NON_DEFERRABLE);
4923 return d;
4924 }
4925
4926 }
4927
4928 /**
4929 * Helper class for method resolution diagnostic simplification.
4930 * Certain resolution diagnostic are rewritten as simpler diagnostic
4931 * where the enclosing resolution diagnostic (i.e. 'inapplicable method')
4932 * is stripped away, as it doesn't carry additional info. The logic
4933 * for matching a given diagnostic is given in terms of a template
4934 * hierarchy: a diagnostic template can be specified programmatically,
4935 * so that only certain diagnostics are matched. Each templete is then
4936 * associated with a rewriter object that carries out the task of rewtiting
4937 * the diagnostic to a simpler one.
4938 */
4939 static class MethodResolutionDiagHelper {
4940
4941 /**
4942 * A diagnostic rewriter transforms a method resolution diagnostic
4943 * into a simpler one
4944 */
4945 interface DiagnosticRewriter {
4946 JCDiagnostic rewriteDiagnostic(JCDiagnostic.Factory diags,
4947 DiagnosticPosition preferredPos, DiagnosticSource preferredSource,
4948 DiagnosticType preferredKind, JCDiagnostic d);
4949 }
4950
4951 /**
4952 * A diagnostic template is made up of two ingredients: (i) a regular
4953 * expression for matching a diagnostic key and (ii) a list of sub-templates
4954 * for matching diagnostic arguments.
4955 */
4956 static class Template {
4957
4958 /** regex used to match diag key */
4959 String regex;
4960
4961 /** templates used to match diagnostic args */
4962 Template[] subTemplates;
4963
4964 Template(String key, Template... subTemplates) {
4965 this.regex = key;
4966 this.subTemplates = subTemplates;
4967 }
4968
4969 /**
4970 * Returns true if the regex matches the diagnostic key and if
4971 * all diagnostic arguments are matches by corresponding sub-templates.
4972 */
4973 boolean matches(Object o) {
4974 JCDiagnostic d = (JCDiagnostic)o;
4975 Object[] args = d.getArgs();
4976 if (!d.getCode().matches(regex) ||
4977 subTemplates.length != d.getArgs().length) {
4978 return false;
4979 }
4980 for (int i = 0; i < args.length ; i++) {
4981 if (!subTemplates[i].matches(args[i])) {
4982 return false;
4983 }
4984 }
4985 return true;
4986 }
4987 }
4988
4989 /**
4990 * Common rewriter for all argument mismatch simplifications.
4991 */
4992 static class ArgMismatchRewriter implements DiagnosticRewriter {
4993
4994 /** the index of the subdiagnostic to be used as primary. */
4995 int causeIndex;
4996
4997 public ArgMismatchRewriter(int causeIndex) {
4998 this.causeIndex = causeIndex;
4999 }
5000
5001 @Override
5002 public JCDiagnostic rewriteDiagnostic(JCDiagnostic.Factory diags,
5003 DiagnosticPosition preferredPos, DiagnosticSource preferredSource,
5004 DiagnosticType preferredKind, JCDiagnostic d) {
5005 JCDiagnostic cause = (JCDiagnostic)d.getArgs()[causeIndex];
5006 DiagnosticPosition pos = d.getDiagnosticPosition();
5007 if (pos == null) {
5008 pos = preferredPos;
5009 }
5010 return diags.create(preferredKind, preferredSource, pos,
5011 "prob.found.req", cause);
5012 }
5013 }
5014
5015 /** a dummy template that match any diagnostic argument */
5016 static final Template skip = new Template("") {
5017 @Override
5018 boolean matches(Object d) {
5019 return true;
5020 }
5021 };
5022
5023 /** template for matching inference-free arguments mismatch failures */
5024 static final Template argMismatchTemplate = new Template(MethodCheckDiag.ARG_MISMATCH.regex(), skip);
5025
5026 /** template for matching inference related arguments mismatch failures */
5027 static final Template inferArgMismatchTemplate = new Template(MethodCheckDiag.ARG_MISMATCH.regex(), skip, skip) {
5028 @Override
5029 boolean matches(Object o) {
5030 if (!super.matches(o)) {
5031 return false;
5032 }
5033 JCDiagnostic d = (JCDiagnostic)o;
5034 @SuppressWarnings("unchecked")
5035 List<Type> tvars = (List<Type>)d.getArgs()[0];
5036 return !containsAny(d, tvars);
5037 }
5038
5039 BiPredicate<Object, List<Type>> containsPredicate = (o, ts) -> {
5040 if (o instanceof Type type) {
5041 return type.containsAny(ts);
5042 } else if (o instanceof JCDiagnostic diagnostic) {
5043 return containsAny(diagnostic, ts);
5044 } else {
5045 return false;
5046 }
5047 };
5048
5049 boolean containsAny(JCDiagnostic d, List<Type> ts) {
5050 return Stream.of(d.getArgs())
5051 .anyMatch(o -> containsPredicate.test(o, ts));
5052 }
5053 };
5054
5055 /** rewriter map used for method resolution simplification */
5056 static final Map<Template, DiagnosticRewriter> rewriters = new LinkedHashMap<>();
5057
5058 static {
5059 rewriters.put(argMismatchTemplate, new ArgMismatchRewriter(0));
5060 rewriters.put(inferArgMismatchTemplate, new ArgMismatchRewriter(1));
5061 }
5062
5063 /**
5064 * Main entry point for diagnostic rewriting - given a diagnostic, see if any templates matches it,
5065 * and rewrite it accordingly.
5066 */
5067 static JCDiagnostic rewrite(JCDiagnostic.Factory diags, DiagnosticPosition pos, DiagnosticSource source,
5068 DiagnosticType dkind, JCDiagnostic d) {
5069 for (Map.Entry<Template, DiagnosticRewriter> _entry : rewriters.entrySet()) {
5070 if (_entry.getKey().matches(d)) {
5071 JCDiagnostic simpleDiag =
5072 _entry.getValue().rewriteDiagnostic(diags, pos, source, dkind, d);
5073 simpleDiag.setFlag(DiagnosticFlag.COMPRESSED);
5074 return simpleDiag;
5075 }
5076 }
5077 return null;
5078 }
5079 }
5080
5081 enum MethodResolutionPhase {
5082 BASIC(false, false),
5083 BOX(true, false),
5084 VARARITY(true, true) {
5085 @Override
5086 public Symbol mergeResults(Symbol bestSoFar, Symbol sym) {
5087 //Check invariants (see {@code LookupHelper.shouldStop})
5088 Assert.check(bestSoFar.kind.isResolutionError() && bestSoFar.kind != AMBIGUOUS);
5089 if (!sym.kind.isResolutionError()) {
5090 //varargs resolution successful
5091 return sym;
5092 } else {
5093 //pick best error
5094 switch (bestSoFar.kind) {
5095 case WRONG_MTH:
5096 case WRONG_MTHS:
5097 //Override previous errors if they were caused by argument mismatch.
5098 //This generally means preferring current symbols - but we need to pay
5099 //attention to the fact that the varargs lookup returns 'less' candidates
5100 //than the previous rounds, and adjust that accordingly.
5101 switch (sym.kind) {
5102 case WRONG_MTH:
5103 //if the previous round matched more than one method, return that
5104 //result instead
5105 return bestSoFar.kind == WRONG_MTHS ?
5106 bestSoFar : sym;
5107 case ABSENT_MTH:
5108 //do not override erroneous symbol if the arity lookup did not
5109 //match any method
5110 return bestSoFar;
5111 case WRONG_MTHS:
5112 default:
5113 //safe to override
5114 return sym;
5115 }
5116 default:
5117 //otherwise, return first error
5118 return bestSoFar;
5119 }
5120 }
5121 }
5122 };
5123
5124 final boolean isBoxingRequired;
5125 final boolean isVarargsRequired;
5126
5127 MethodResolutionPhase(boolean isBoxingRequired, boolean isVarargsRequired) {
5128 this.isBoxingRequired = isBoxingRequired;
5129 this.isVarargsRequired = isVarargsRequired;
5130 }
5131
5132 public boolean isBoxingRequired() {
5133 return isBoxingRequired;
5134 }
5135
5136 public boolean isVarargsRequired() {
5137 return isVarargsRequired;
5138 }
5139
5140 public Symbol mergeResults(Symbol prev, Symbol sym) {
5141 return sym;
5142 }
5143 }
5144
5145 final List<MethodResolutionPhase> methodResolutionSteps = List.of(BASIC, BOX, VARARITY);
5146
5147 /**
5148 * A resolution context is used to keep track of intermediate results of
5149 * overload resolution, such as list of method that are not applicable
5150 * (used to generate more precise diagnostics) and so on. Resolution contexts
5151 * can be nested - this means that when each overload resolution routine should
5152 * work within the resolution context it created.
5153 */
5154 class MethodResolutionContext {
5155
5156 private List<Candidate> candidates = List.nil();
5157
5158 MethodResolutionPhase step = null;
5159
5160 MethodCheck methodCheck = resolveMethodCheck;
5161
5162 private boolean internalResolution = false;
5163 private DeferredAttr.AttrMode attrMode = DeferredAttr.AttrMode.SPECULATIVE;
5164
5165 void addInapplicableCandidate(Symbol sym, JCDiagnostic details) {
5166 Candidate c = new Candidate(currentResolutionContext.step, sym, details, null);
5167 candidates = candidates.append(c);
5168 }
5169
5170 void addApplicableCandidate(Symbol sym, Type mtype) {
5171 Candidate c = new Candidate(currentResolutionContext.step, sym, null, mtype);
5172 candidates = candidates.append(c);
5173 }
5174
5175 DeferredAttrContext deferredAttrContext(Symbol sym, InferenceContext inferenceContext, ResultInfo pendingResult, Warner warn) {
5176 DeferredAttrContext parent = (pendingResult == null)
5177 ? deferredAttr.emptyDeferredAttrContext
5178 : pendingResult.checkContext.deferredAttrContext();
5179 return deferredAttr.new DeferredAttrContext(attrMode, sym, step,
5180 inferenceContext, parent, warn);
5181 }
5182
5183 /**
5184 * This class represents an overload resolution candidate. There are two
5185 * kinds of candidates: applicable methods and inapplicable methods;
5186 * applicable methods have a pointer to the instantiated method type,
5187 * while inapplicable candidates contain further details about the
5188 * reason why the method has been considered inapplicable.
5189 */
5190 @SuppressWarnings("overrides")
5191 class Candidate {
5192
5193 final MethodResolutionPhase step;
5194 final Symbol sym;
5195 final JCDiagnostic details;
5196 final Type mtype;
5197
5198 private Candidate(MethodResolutionPhase step, Symbol sym, JCDiagnostic details, Type mtype) {
5199 this.step = step;
5200 this.sym = sym;
5201 this.details = details;
5202 this.mtype = mtype;
5203 }
5204
5205 boolean isApplicable() {
5206 return mtype != null;
5207 }
5208 }
5209
5210 DeferredAttr.AttrMode attrMode() {
5211 return attrMode;
5212 }
5213
5214 boolean internal() {
5215 return internalResolution;
5216 }
5217 }
5218
5219 MethodResolutionContext currentResolutionContext = null;
5220 }