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 private final boolean allowPrivateMembersInPermitsClause;
115 final EnumSet<VerboseResolutionMode> verboseResolutionMode;
116 final boolean dumpMethodReferenceSearchResults;
117 final boolean dumpStacktraceOnError;
118
119 WriteableScope polymorphicSignatureScope;
120
121 @SuppressWarnings("this-escape")
122 protected Resolve(Context context) {
123 context.put(resolveKey, this);
124 syms = Symtab.instance(context);
125
126 varNotFound = new SymbolNotFoundError(ABSENT_VAR);
127 methodNotFound = new SymbolNotFoundError(ABSENT_MTH);
128 typeNotFound = new SymbolNotFoundError(ABSENT_TYP);
129 referenceNotFound = ReferenceLookupResult.error(methodNotFound);
130
131 names = Names.instance(context);
132 log = Log.instance(context);
133 attr = Attr.instance(context);
134 attrRecover = AttrRecover.instance(context);
135 deferredAttr = DeferredAttr.instance(context);
136 chk = Check.instance(context);
137 infer = Infer.instance(context);
138 finder = ClassFinder.instance(context);
139 moduleFinder = ModuleFinder.instance(context);
140 types = Types.instance(context);
141 diags = JCDiagnostic.Factory.instance(context);
142 preview = Preview.instance(context);
143 Source source = Source.instance(context);
144 Options options = Options.instance(context);
145 compactMethodDiags = options.isSet(Option.XDIAGS, "compact") ||
146 options.isUnset(Option.XDIAGS) && options.isUnset("rawDiagnostics");
147 verboseResolutionMode = VerboseResolutionMode.getVerboseResolutionMode(options);
148 Target target = Target.instance(context);
149 allowLocalVariableTypeInference = Feature.LOCAL_VARIABLE_TYPE_INFERENCE.allowedInSource(source);
150 allowYieldStatement = Feature.SWITCH_EXPRESSION.allowedInSource(source);
151 allowPrivateMembersInPermitsClause = Feature.PRIVATE_MEMBERS_IN_PERMITS_CLAUSE.allowedInSource(source);
152 polymorphicSignatureScope = WriteableScope.create(syms.noSymbol);
153 allowModules = Feature.MODULES.allowedInSource(source);
154 allowRecords = Feature.RECORDS.allowedInSource(source);
155 dumpMethodReferenceSearchResults = options.isSet("debug.dumpMethodReferenceSearchResults");
156 dumpStacktraceOnError = options.isSet("dev") || options.isSet(DOE);
157 }
158
159 /** error symbols, which are returned when resolution fails
160 */
161 private final SymbolNotFoundError varNotFound;
162 private final SymbolNotFoundError methodNotFound;
163 private final SymbolNotFoundError typeNotFound;
164
165 /** empty reference lookup result */
166 private final ReferenceLookupResult referenceNotFound;
167
168 public static Resolve instance(Context context) {
169 Resolve instance = context.get(resolveKey);
170 if (instance == null)
171 instance = new Resolve(context);
172 return instance;
173 }
174
175 private static Symbol bestOf(Symbol s1,
176 Symbol s2) {
177 return s1.kind.betterThan(s2.kind) ? s1 : s2;
178 }
179
180 // <editor-fold defaultstate="collapsed" desc="Verbose resolution diagnostics support">
181 enum VerboseResolutionMode {
182 SUCCESS("success"),
183 FAILURE("failure"),
184 APPLICABLE("applicable"),
185 INAPPLICABLE("inapplicable"),
186 DEFERRED_INST("deferred-inference"),
187 PREDEF("predef"),
188 OBJECT_INIT("object-init"),
189 INTERNAL("internal");
190
191 final String opt;
192
193 private VerboseResolutionMode(String opt) {
194 this.opt = opt;
195 }
196
197 static EnumSet<VerboseResolutionMode> getVerboseResolutionMode(Options opts) {
198 String s = opts.get("debug.verboseResolution");
199 EnumSet<VerboseResolutionMode> res = EnumSet.noneOf(VerboseResolutionMode.class);
200 if (s == null) return res;
201 if (s.contains("all")) {
202 res = EnumSet.allOf(VerboseResolutionMode.class);
203 }
204 Collection<String> args = Arrays.asList(s.split(","));
205 for (VerboseResolutionMode mode : values()) {
206 if (args.contains(mode.opt)) {
207 res.add(mode);
208 } else if (args.contains("-" + mode.opt)) {
209 res.remove(mode);
210 }
211 }
212 return res;
213 }
214 }
215
216 void reportVerboseResolutionDiagnostic(DiagnosticPosition dpos, Name name, Type site,
217 List<Type> argtypes, List<Type> typeargtypes, Symbol bestSoFar) {
218 boolean success = !bestSoFar.kind.isResolutionError();
219
220 if (success && !verboseResolutionMode.contains(VerboseResolutionMode.SUCCESS)) {
221 return;
222 } else if (!success && !verboseResolutionMode.contains(VerboseResolutionMode.FAILURE)) {
223 return;
224 }
225
226 if (bestSoFar.name == names.init &&
227 bestSoFar.owner == syms.objectType.tsym &&
228 !verboseResolutionMode.contains(VerboseResolutionMode.OBJECT_INIT)) {
229 return; //skip diags for Object constructor resolution
230 } else if (site == syms.predefClass.type &&
231 !verboseResolutionMode.contains(VerboseResolutionMode.PREDEF)) {
232 return; //skip spurious diags for predef symbols (i.e. operators)
233 } else if (currentResolutionContext.internalResolution &&
234 !verboseResolutionMode.contains(VerboseResolutionMode.INTERNAL)) {
235 return;
236 }
237
238 int pos = 0;
239 int mostSpecificPos = -1;
240 ListBuffer<JCDiagnostic> subDiags = new ListBuffer<>();
241 for (Candidate c : currentResolutionContext.candidates) {
242 if (currentResolutionContext.step != c.step ||
243 (c.isApplicable() && !verboseResolutionMode.contains(VerboseResolutionMode.APPLICABLE)) ||
244 (!c.isApplicable() && !verboseResolutionMode.contains(VerboseResolutionMode.INAPPLICABLE))) {
245 continue;
246 } else {
247 subDiags.append(c.isApplicable() ?
248 getVerboseApplicableCandidateDiag(pos, c.sym, c.mtype) :
249 getVerboseInapplicableCandidateDiag(pos, c.sym, c.details));
250 if (c.sym == bestSoFar)
251 mostSpecificPos = pos;
252 pos++;
253 }
254 }
255 String key = success ? "verbose.resolve.multi" : "verbose.resolve.multi.1";
256 List<Type> argtypes2 = argtypes.map(deferredAttr.new RecoveryDeferredTypeMap(AttrMode.SPECULATIVE, bestSoFar, currentResolutionContext.step));
257 JCDiagnostic main = diags.note(log.currentSource(), dpos, key, name,
258 site.tsym, mostSpecificPos, currentResolutionContext.step,
259 methodArguments(argtypes2),
260 methodArguments(typeargtypes));
261 JCDiagnostic d = new JCDiagnostic.MultilineDiagnostic(main, subDiags.toList());
262 log.report(d);
263 }
264
265 JCDiagnostic getVerboseApplicableCandidateDiag(int pos, Symbol sym, Type inst) {
266 JCDiagnostic subDiag = null;
267 if (sym.type.hasTag(FORALL)) {
268 subDiag = diags.fragment(Fragments.PartialInstSig(inst));
269 }
270
271 String key = subDiag == null ?
272 "applicable.method.found" :
273 "applicable.method.found.1";
274
275 return diags.fragment(key, pos, sym, subDiag);
276 }
277
278 JCDiagnostic getVerboseInapplicableCandidateDiag(int pos, Symbol sym, JCDiagnostic subDiag) {
279 return diags.fragment(Fragments.NotApplicableMethodFound(pos, sym, subDiag));
280 }
281 // </editor-fold>
282
283 /* ************************************************************************
284 * Identifier resolution
285 *************************************************************************/
286
287 /** An environment is "static" if its static level is greater than
288 * the one of its outer environment
289 */
290 protected static boolean isStatic(Env<AttrContext> env) {
291 return env.outer != null && env.info.staticLevel > env.outer.info.staticLevel;
292 }
293
294 /** An environment is an "initializer" if it is a constructor or
295 * an instance initializer.
296 */
297 static boolean isInitializer(Env<AttrContext> env) {
298 Symbol owner = env.info.scope.owner;
299 return owner.isConstructor() ||
300 owner.owner.kind == TYP &&
301 (owner.kind == VAR ||
302 owner.kind == MTH && (owner.flags() & BLOCK) != 0) &&
303 (owner.flags() & STATIC) == 0;
304 }
305
306 /** Is class accessible in given environment?
307 * @param env The current environment.
308 * @param c The class whose accessibility is checked.
309 */
310 public boolean isAccessible(Env<AttrContext> env, TypeSymbol c) {
311 return isAccessible(env, c, false);
312 }
313
314 public boolean isAccessible(Env<AttrContext> env, TypeSymbol c, boolean checkInner) {
315
316 /* 15.9.5.1: Note that it is possible for the signature of the anonymous constructor
317 to refer to an inaccessible type
318 */
319 if (env.enclMethod != null && (env.enclMethod.mods.flags & ANONCONSTR) != 0)
320 return true;
321
322 if (env.info.visitingServiceImplementation &&
323 env.toplevel.modle == c.packge().modle) {
324 return true;
325 }
326
327 boolean isAccessible = false;
328 switch ((short)(c.flags() & AccessFlags)) {
329 case PRIVATE:
330 isAccessible =
331 env.enclClass.sym.outermostClass() ==
332 c.owner.outermostClass();
333 break;
334 case 0:
335 isAccessible =
336 env.toplevel.packge == c.owner // fast special case
337 ||
338 env.toplevel.packge == c.packge();
339 break;
340 default: // error recovery
341 isAccessible = true;
342 break;
343 case PUBLIC:
344 if (allowModules) {
345 ModuleSymbol currModule = env.toplevel.modle;
346 currModule.complete();
347 PackageSymbol p = c.packge();
348 isAccessible =
349 currModule == p.modle ||
350 currModule.visiblePackages.get(p.fullname) == p ||
351 p == syms.rootPackage ||
352 (p.modle == syms.unnamedModule && currModule.readModules.contains(p.modle));
353 } else {
354 isAccessible = true;
355 }
356 break;
357 case PROTECTED:
358 isAccessible =
359 env.toplevel.packge == c.owner // fast special case
360 ||
361 env.toplevel.packge == c.packge()
362 ||
363 isInnerSubClass(env.enclClass.sym, c.owner)
364 ||
365 env.info.allowProtectedAccess;
366 break;
367 }
368 return (checkInner == false || c.type.getEnclosingType() == Type.noType) ?
369 isAccessible :
370 isAccessible && isAccessible(env, c.type.getEnclosingType(), checkInner);
371 }
372 //where
373 /** Is given class a subclass of given base class, or an inner class
374 * of a subclass?
375 * Return null if no such class exists.
376 * @param c The class which is the subclass or is contained in it.
377 * @param base The base class
378 */
379 private boolean isInnerSubClass(ClassSymbol c, Symbol base) {
380 while (c != null && !c.isSubClass(base, types)) {
381 c = c.owner.enclClass();
382 }
383 return c != null;
384 }
385
386 boolean isAccessible(Env<AttrContext> env, Type t) {
387 return isAccessible(env, t, false);
388 }
389
390 boolean isAccessible(Env<AttrContext> env, Type t, boolean checkInner) {
391 if (t.hasTag(ARRAY)) {
392 return isAccessible(env, types.cvarUpperBound(types.elemtype(t)));
393 } else if (t.isUnion()) {
394 return StreamSupport.stream(((UnionClassType) t).getAlternativeTypes().spliterator(), false)
395 .allMatch(alternative -> isAccessible(env, alternative.tsym, checkInner));
396 } else {
397 return isAccessible(env, t.tsym, checkInner);
398 }
399 }
400
401 /** Is symbol accessible as a member of given type in given environment?
402 * @param env The current environment.
403 * @param site The type of which the tested symbol is regarded
404 * as a member.
405 * @param sym The symbol.
406 */
407 public boolean isAccessible(Env<AttrContext> env, Type site, Symbol sym) {
408 return isAccessible(env, site, sym, false);
409 }
410 public boolean isAccessible(Env<AttrContext> env, Type site, Symbol sym, boolean checkInner) {
411 if (sym.name == names.init && sym.owner != site.tsym) return false;
412
413 /* 15.9.5.1: Note that it is possible for the signature of the anonymous constructor
414 to refer to an inaccessible type
415 */
416 if (env.enclMethod != null && (env.enclMethod.mods.flags & ANONCONSTR) != 0)
417 return true;
418
419 if (env.info.visitingServiceImplementation &&
420 env.toplevel.modle == sym.packge().modle) {
421 return true;
422 }
423
424 ClassSymbol enclosingCsym = env.enclClass.sym;
425 try {
426 switch ((short)(sym.flags() & AccessFlags)) {
427 case PRIVATE:
428 return
429 (env.enclClass.sym == sym.owner // fast special case
430 ||
431 env.enclClass.sym.outermostClass() ==
432 sym.owner.outermostClass()
433 ||
434 privateMemberInPermitsClauseIfAllowed(env, sym))
435 &&
436 sym.isInheritedIn(site.tsym, types);
437 case 0:
438 return
439 (env.toplevel.packge == sym.owner.owner // fast special case
440 ||
441 env.toplevel.packge == sym.packge())
442 &&
443 isAccessible(env, site, checkInner)
444 &&
445 sym.isInheritedIn(site.tsym, types)
446 &&
447 notOverriddenIn(site, sym);
448 case PROTECTED:
449 return
450 (env.toplevel.packge == sym.owner.owner // fast special case
451 ||
452 env.toplevel.packge == sym.packge()
453 ||
454 isProtectedAccessible(sym, env.enclClass.sym, site)
455 ||
456 // OK to select instance method or field from 'super' or type name
457 // (but type names should be disallowed elsewhere!)
458 env.info.selectSuper && (sym.flags() & STATIC) == 0 && sym.kind != TYP)
459 &&
460 isAccessible(env, site, checkInner)
461 &&
462 notOverriddenIn(site, sym);
463 default: // this case includes erroneous combinations as well
464 return isAccessible(env, site, checkInner) && notOverriddenIn(site, sym);
465 }
466 } finally {
467 env.enclClass.sym = enclosingCsym;
468 }
469 }
470
471 private boolean privateMemberInPermitsClauseIfAllowed(Env<AttrContext> env, Symbol sym) {
472 return allowPrivateMembersInPermitsClause &&
473 env.info.isPermitsClause &&
474 ((JCClassDecl) env.tree).sym.outermostClass() == sym.owner.outermostClass();
475 }
476
477 //where
478 /* `sym' is accessible only if not overridden by
479 * another symbol which is a member of `site'
480 * (because, if it is overridden, `sym' is not strictly
481 * speaking a member of `site'). A polymorphic signature method
482 * cannot be overridden (e.g. MH.invokeExact(Object[])).
483 */
484 private boolean notOverriddenIn(Type site, Symbol sym) {
485 if (sym.kind != MTH || sym.isConstructor() || sym.isStatic())
486 return true;
487 else {
488 Symbol s2 = ((MethodSymbol)sym).implementation(site.tsym, types, true);
489 return (s2 == null || s2 == sym || sym.owner == s2.owner || (sym.owner.isInterface() && s2.owner == syms.objectType.tsym) ||
490 !types.isSubSignature(types.memberType(site, s2), types.memberType(site, sym)));
491 }
492 }
493 //where
494 /** Is given protected symbol accessible if it is selected from given site
495 * and the selection takes place in given class?
496 * @param sym The symbol with protected access
497 * @param c The class where the access takes place
498 * @param site The type of the qualifier
499 */
500 private
501 boolean isProtectedAccessible(Symbol sym, ClassSymbol c, Type site) {
502 Type newSite = site.hasTag(TYPEVAR) ? site.getUpperBound() : site;
503 while (c != null &&
504 !(c.isSubClass(sym.owner, types) &&
505 (c.flags() & INTERFACE) == 0 &&
506 // In JLS 2e 6.6.2.1, the subclass restriction applies
507 // only to instance fields and methods -- types are excluded
508 // regardless of whether they are declared 'static' or not.
509 ((sym.flags() & STATIC) != 0 || sym.kind == TYP || newSite.tsym.isSubClass(c, types))))
510 c = c.owner.enclClass();
511 return c != null;
512 }
513
514 /**
515 * Performs a recursive scan of a type looking for accessibility problems
516 * from current attribution environment
517 */
518 void checkAccessibleType(Env<AttrContext> env, Type t) {
519 accessibilityChecker.visit(t, env);
520 }
521
522 /**
523 * Accessibility type-visitor
524 */
525 Types.SimpleVisitor<Void, Env<AttrContext>> accessibilityChecker =
526 new Types.SimpleVisitor<Void, Env<AttrContext>>() {
527
528 void visit(List<Type> ts, Env<AttrContext> env) {
529 for (Type t : ts) {
530 visit(t, env);
531 }
532 }
533
534 public Void visitType(Type t, Env<AttrContext> env) {
535 return null;
536 }
537
538 @Override
539 public Void visitArrayType(ArrayType t, Env<AttrContext> env) {
540 visit(t.elemtype, env);
541 return null;
542 }
543
544 @Override
545 public Void visitClassType(ClassType t, Env<AttrContext> env) {
546 visit(t.getTypeArguments(), env);
547 if (!isAccessible(env, t, true)) {
548 accessBase(new AccessError(env, null, t.tsym), env.tree.pos(), env.enclClass.sym, t, t.tsym.name, true);
549 }
550 return null;
551 }
552
553 @Override
554 public Void visitWildcardType(WildcardType t, Env<AttrContext> env) {
555 visit(t.type, env);
556 return null;
557 }
558
559 @Override
560 public Void visitMethodType(MethodType t, Env<AttrContext> env) {
561 visit(t.getParameterTypes(), env);
562 visit(t.getReturnType(), env);
563 visit(t.getThrownTypes(), env);
564 return null;
565 }
566 };
567
568 /** Try to instantiate the type of a method so that it fits
569 * given type arguments and argument types. If successful, return
570 * the method's instantiated type, else return null.
571 * The instantiation will take into account an additional leading
572 * formal parameter if the method is an instance method seen as a member
573 * of an under determined site. In this case, we treat site as an additional
574 * parameter and the parameters of the class containing the method as
575 * additional type variables that get instantiated.
576 *
577 * @param env The current environment
578 * @param site The type of which the method is a member.
579 * @param m The method symbol.
580 * @param argtypes The invocation's given value arguments.
581 * @param typeargtypes The invocation's given type arguments.
582 * @param allowBoxing Allow boxing conversions of arguments.
583 * @param useVarargs Box trailing arguments into an array for varargs.
584 */
585 Type rawInstantiate(Env<AttrContext> env,
586 Type site,
587 Symbol m,
588 ResultInfo resultInfo,
589 List<Type> argtypes,
590 List<Type> typeargtypes,
591 boolean allowBoxing,
592 boolean useVarargs,
593 Warner warn) throws Infer.InferenceException {
594 Type mt = types.memberType(site, m);
595 // tvars is the list of formal type variables for which type arguments
596 // need to inferred.
597 List<Type> tvars = List.nil();
598 if (typeargtypes == null) typeargtypes = List.nil();
599 if (!mt.hasTag(FORALL) && typeargtypes.nonEmpty()) {
600 // This is not a polymorphic method, but typeargs are supplied
601 // which is fine, see JLS 15.12.2.1
602 } else if (mt.hasTag(FORALL) && typeargtypes.nonEmpty()) {
603 ForAll pmt = (ForAll) mt;
604 if (typeargtypes.length() != pmt.tvars.length())
605 // not enough args
606 throw new InapplicableMethodException(diags.fragment(Fragments.WrongNumberTypeArgs(Integer.toString(pmt.tvars.length()))), dumpStacktraceOnError);
607 // Check type arguments are within bounds
608 List<Type> formals = pmt.tvars;
609 List<Type> actuals = typeargtypes;
610 while (formals.nonEmpty() && actuals.nonEmpty()) {
611 List<Type> bounds = types.subst(types.getBounds((TypeVar)formals.head),
612 pmt.tvars, typeargtypes);
613 for (; bounds.nonEmpty(); bounds = bounds.tail) {
614 if (!types.isSubtypeUnchecked(actuals.head, bounds.head, warn)) {
615 throw new InapplicableMethodException(diags.fragment(Fragments.ExplicitParamDoNotConformToBounds(actuals.head, bounds)), dumpStacktraceOnError);
616 }
617 }
618 formals = formals.tail;
619 actuals = actuals.tail;
620 }
621 mt = types.subst(pmt.qtype, pmt.tvars, typeargtypes);
622 } else if (mt.hasTag(FORALL)) {
623 ForAll pmt = (ForAll) mt;
624 List<Type> tvars1 = types.newInstances(pmt.tvars);
625 tvars = tvars.appendList(tvars1);
626 mt = types.subst(pmt.qtype, pmt.tvars, tvars1);
627 }
628
629 // find out whether we need to go the slow route via infer
630 boolean instNeeded = tvars.tail != null; /*inlined: tvars.nonEmpty()*/
631 for (List<Type> l = argtypes;
632 l.tail != null/*inlined: l.nonEmpty()*/ && !instNeeded;
633 l = l.tail) {
634 if (l.head.hasTag(FORALL)) instNeeded = true;
635 }
636
637 if (instNeeded) {
638 return infer.instantiateMethod(env,
639 tvars,
640 (MethodType)mt,
641 resultInfo,
642 (MethodSymbol)m,
643 argtypes,
644 allowBoxing,
645 useVarargs,
646 currentResolutionContext,
647 warn);
648 }
649
650 DeferredAttr.DeferredAttrContext dc = currentResolutionContext.deferredAttrContext(m, infer.emptyContext, resultInfo, warn);
651 currentResolutionContext.methodCheck.argumentsAcceptable(env, dc,
652 argtypes, mt.getParameterTypes(), warn);
653 dc.complete();
654 return mt;
655 }
656
657 Type checkMethod(Env<AttrContext> env,
658 Type site,
659 Symbol m,
660 ResultInfo resultInfo,
661 List<Type> argtypes,
662 List<Type> typeargtypes,
663 Warner warn) {
664 MethodResolutionContext prevContext = currentResolutionContext;
665 try {
666 currentResolutionContext = new MethodResolutionContext();
667 currentResolutionContext.attrMode = (resultInfo.pt == Infer.anyPoly) ?
668 AttrMode.SPECULATIVE : DeferredAttr.AttrMode.CHECK;
669 if (env.tree.hasTag(JCTree.Tag.REFERENCE)) {
670 //method/constructor references need special check class
671 //to handle inference variables in 'argtypes' (might happen
672 //during an unsticking round)
673 currentResolutionContext.methodCheck =
674 new MethodReferenceCheck(resultInfo.checkContext.inferenceContext());
675 }
676 MethodResolutionPhase step = currentResolutionContext.step = env.info.pendingResolutionPhase;
677 return rawInstantiate(env, site, m, resultInfo, argtypes, typeargtypes,
678 step.isBoxingRequired(), step.isVarargsRequired(), warn);
679 }
680 finally {
681 currentResolutionContext = prevContext;
682 }
683 }
684
685 /** Same but returns null instead throwing a NoInstanceException
686 */
687 Type instantiate(Env<AttrContext> env,
688 Type site,
689 Symbol m,
690 ResultInfo resultInfo,
691 List<Type> argtypes,
692 List<Type> typeargtypes,
693 boolean allowBoxing,
694 boolean useVarargs,
695 Warner warn) {
696 try {
697 return rawInstantiate(env, site, m, resultInfo, argtypes, typeargtypes,
698 allowBoxing, useVarargs, warn);
699 } catch (InapplicableMethodException ex) {
700 return null;
701 }
702 }
703
704 /**
705 * This interface defines an entry point that should be used to perform a
706 * method check. A method check usually consist in determining as to whether
707 * a set of types (actuals) is compatible with another set of types (formals).
708 * Since the notion of compatibility can vary depending on the circumstances,
709 * this interfaces allows to easily add new pluggable method check routines.
710 */
711 interface MethodCheck {
712 /**
713 * Main method check routine. A method check usually consist in determining
714 * as to whether a set of types (actuals) is compatible with another set of
715 * types (formals). If an incompatibility is found, an unchecked exception
716 * is assumed to be thrown.
717 */
718 void argumentsAcceptable(Env<AttrContext> env,
719 DeferredAttrContext deferredAttrContext,
720 List<Type> argtypes,
721 List<Type> formals,
722 Warner warn);
723
724 /**
725 * Retrieve the method check object that will be used during a
726 * most specific check.
727 */
728 MethodCheck mostSpecificCheck(List<Type> actuals);
729 }
730
731 /**
732 * Helper enum defining all method check diagnostics (used by resolveMethodCheck).
733 */
734 enum MethodCheckDiag {
735 /**
736 * Actuals and formals differs in length.
737 */
738 ARITY_MISMATCH("arg.length.mismatch", "infer.arg.length.mismatch"),
739 /**
740 * An actual is incompatible with a formal.
741 */
742 ARG_MISMATCH("no.conforming.assignment.exists", "infer.no.conforming.assignment.exists"),
743 /**
744 * An actual is incompatible with the varargs element type.
745 */
746 VARARG_MISMATCH("varargs.argument.mismatch", "infer.varargs.argument.mismatch"),
747 /**
748 * The varargs element type is inaccessible.
749 */
750 INACCESSIBLE_VARARGS("inaccessible.varargs.type", "inaccessible.varargs.type");
751
752 final String basicKey;
753 final String inferKey;
754
755 MethodCheckDiag(String basicKey, String inferKey) {
756 this.basicKey = basicKey;
757 this.inferKey = inferKey;
758 }
759
760 String regex() {
761 return String.format("([a-z]*\\.)*(%s|%s)", basicKey, inferKey);
762 }
763 }
764
765 /**
766 * Dummy method check object. All methods are deemed applicable, regardless
767 * of their formal parameter types.
768 */
769 MethodCheck nilMethodCheck = new MethodCheck() {
770 public void argumentsAcceptable(Env<AttrContext> env, DeferredAttrContext deferredAttrContext, List<Type> argtypes, List<Type> formals, Warner warn) {
771 //do nothing - method always applicable regardless of actuals
772 }
773
774 public MethodCheck mostSpecificCheck(List<Type> actuals) {
775 return this;
776 }
777 };
778
779 /**
780 * Base class for 'real' method checks. The class defines the logic for
781 * iterating through formals and actuals and provides and entry point
782 * that can be used by subclasses in order to define the actual check logic.
783 */
784 abstract class AbstractMethodCheck implements MethodCheck {
785 @Override
786 public void argumentsAcceptable(final Env<AttrContext> env,
787 DeferredAttrContext deferredAttrContext,
788 List<Type> argtypes,
789 List<Type> formals,
790 Warner warn) {
791 //should we expand formals?
792 boolean useVarargs = deferredAttrContext.phase.isVarargsRequired();
793 JCTree callTree = treeForDiagnostics(env);
794 List<JCExpression> trees = TreeInfo.args(callTree);
795
796 //inference context used during this method check
797 InferenceContext inferenceContext = deferredAttrContext.inferenceContext;
798
799 Type varargsFormal = useVarargs ? formals.last() : null;
800
801 if (varargsFormal == null &&
802 argtypes.size() != formals.size()) {
803 reportMC(callTree, MethodCheckDiag.ARITY_MISMATCH, inferenceContext); // not enough args
804 }
805
806 while (argtypes.nonEmpty() && formals.head != varargsFormal) {
807 DiagnosticPosition pos = trees != null ? trees.head : null;
808 checkArg(pos, false, argtypes.head, formals.head, deferredAttrContext, warn);
809 argtypes = argtypes.tail;
810 formals = formals.tail;
811 trees = trees != null ? trees.tail : trees;
812 }
813
814 if (formals.head != varargsFormal) {
815 reportMC(callTree, MethodCheckDiag.ARITY_MISMATCH, inferenceContext); // not enough args
816 }
817
818 if (useVarargs) {
819 //note: if applicability check is triggered by most specific test,
820 //the last argument of a varargs is _not_ an array type (see JLS 15.12.2.5)
821 final Type elt = types.elemtype(varargsFormal);
822 while (argtypes.nonEmpty()) {
823 DiagnosticPosition pos = trees != null ? trees.head : null;
824 checkArg(pos, true, argtypes.head, elt, deferredAttrContext, warn);
825 argtypes = argtypes.tail;
826 trees = trees != null ? trees.tail : trees;
827 }
828 }
829 }
830
831 // where
832 private JCTree treeForDiagnostics(Env<AttrContext> env) {
833 return env.info.preferredTreeForDiagnostics != null ? env.info.preferredTreeForDiagnostics : env.tree;
834 }
835
836 /**
837 * Does the actual argument conforms to the corresponding formal?
838 */
839 abstract void checkArg(DiagnosticPosition pos, boolean varargs, Type actual, Type formal, DeferredAttrContext deferredAttrContext, Warner warn);
840
841 protected void reportMC(DiagnosticPosition pos, MethodCheckDiag diag, InferenceContext inferenceContext, Object... args) {
842 boolean inferDiag = inferenceContext != infer.emptyContext;
843 if (inferDiag && (!diag.inferKey.equals(diag.basicKey))) {
844 Object[] args2 = new Object[args.length + 1];
845 System.arraycopy(args, 0, args2, 1, args.length);
846 args2[0] = inferenceContext.inferenceVars();
847 args = args2;
848 }
849 String key = inferDiag ? diag.inferKey : diag.basicKey;
850 throw inferDiag ?
851 infer.error(diags.create(DiagnosticType.FRAGMENT, log.currentSource(), pos, key, args)) :
852 getMethodCheckFailure().setMessage(diags.create(DiagnosticType.FRAGMENT, log.currentSource(), pos, key, args));
853 }
854
855 /**
856 * To eliminate the overhead associated with allocating an exception object in such an
857 * hot execution path, we use flyweight pattern - and share the same exception instance
858 * across multiple method check failures.
859 */
860 class SharedInapplicableMethodException extends InapplicableMethodException {
861 private static final long serialVersionUID = 0;
862
863 SharedInapplicableMethodException() {
864 super(null, Resolve.this.dumpStacktraceOnError);
865 }
866
867 SharedInapplicableMethodException setMessage(JCDiagnostic details) {
868 this.diagnostic = details;
869 return this;
870 }
871 }
872
873 private SharedInapplicableMethodException methodCheckFailure;
874
875 public MethodCheck mostSpecificCheck(List<Type> actuals) {
876 return nilMethodCheck;
877 }
878
879 private SharedInapplicableMethodException getMethodCheckFailure() {
880 return methodCheckFailure == null ? methodCheckFailure = new SharedInapplicableMethodException() : methodCheckFailure;
881 }
882 }
883
884 /**
885 * Arity-based method check. A method is applicable if the number of actuals
886 * supplied conforms to the method signature.
887 */
888 MethodCheck arityMethodCheck = new AbstractMethodCheck() {
889 @Override
890 void checkArg(DiagnosticPosition pos, boolean varargs, Type actual, Type formal, DeferredAttrContext deferredAttrContext, Warner warn) {
891 //do nothing - actual always compatible to formals
892 }
893
894 @Override
895 public String toString() {
896 return "arityMethodCheck";
897 }
898 };
899
900 /**
901 * Main method applicability routine. Given a list of actual types A,
902 * a list of formal types F, determines whether the types in A are
903 * compatible (by method invocation conversion) with the types in F.
904 *
905 * Since this routine is shared between overload resolution and method
906 * type-inference, a (possibly empty) inference context is used to convert
907 * formal types to the corresponding 'undet' form ahead of a compatibility
908 * check so that constraints can be propagated and collected.
909 *
910 * Moreover, if one or more types in A is a deferred type, this routine uses
911 * DeferredAttr in order to perform deferred attribution. If one or more actual
912 * deferred types are stuck, they are placed in a queue and revisited later
913 * after the remainder of the arguments have been seen. If this is not sufficient
914 * to 'unstuck' the argument, a cyclic inference error is called out.
915 *
916 * A method check handler (see above) is used in order to report errors.
917 */
918 MethodCheck resolveMethodCheck = new AbstractMethodCheck() {
919
920 @Override
921 void checkArg(DiagnosticPosition pos, boolean varargs, Type actual, Type formal, DeferredAttrContext deferredAttrContext, Warner warn) {
922 ResultInfo mresult = methodCheckResult(varargs, formal, deferredAttrContext, warn);
923 mresult.check(pos, actual);
924 }
925
926 @Override
927 public void argumentsAcceptable(final Env<AttrContext> env,
928 DeferredAttrContext deferredAttrContext,
929 List<Type> argtypes,
930 List<Type> formals,
931 Warner warn) {
932 super.argumentsAcceptable(env, deferredAttrContext, argtypes, formals, warn);
933 // should we check varargs element type accessibility?
934 if (deferredAttrContext.phase.isVarargsRequired()) {
935 if (deferredAttrContext.mode == AttrMode.CHECK) {
936 varargsAccessible(env, types.elemtype(formals.last()), deferredAttrContext.inferenceContext);
937 }
938 }
939 }
940
941 /**
942 * Test that the runtime array element type corresponding to 't' is accessible. 't' should be the
943 * varargs element type of either the method invocation type signature (after inference completes)
944 * or the method declaration signature (before inference completes).
945 */
946 private void varargsAccessible(final Env<AttrContext> env, final Type t, final InferenceContext inferenceContext) {
947 if (inferenceContext.free(t)) {
948 inferenceContext.addFreeTypeListener(List.of(t),
949 solvedContext -> varargsAccessible(env, solvedContext.asInstType(t), solvedContext));
950 } else {
951 if (!isAccessible(env, types.erasure(t))) {
952 Symbol location = env.enclClass.sym;
953 reportMC(env.tree, MethodCheckDiag.INACCESSIBLE_VARARGS, inferenceContext, t, Kinds.kindName(location), location);
954 }
955 }
956 }
957
958 private ResultInfo methodCheckResult(final boolean varargsCheck, Type to,
959 final DeferredAttr.DeferredAttrContext deferredAttrContext, Warner rsWarner) {
960 CheckContext checkContext = new MethodCheckContext(!deferredAttrContext.phase.isBoxingRequired(), deferredAttrContext, rsWarner) {
961 MethodCheckDiag methodDiag = varargsCheck ?
962 MethodCheckDiag.VARARG_MISMATCH : MethodCheckDiag.ARG_MISMATCH;
963
964 @Override
965 public void report(DiagnosticPosition pos, JCDiagnostic details) {
966 reportMC(pos, methodDiag, deferredAttrContext.inferenceContext, details);
967 }
968 };
969 return new MethodResultInfo(to, checkContext);
970 }
971
972 @Override
973 public MethodCheck mostSpecificCheck(List<Type> actuals) {
974 return new MostSpecificCheck(actuals);
975 }
976
977 @Override
978 public String toString() {
979 return "resolveMethodCheck";
980 }
981 };
982
983 /**
984 * This class handles method reference applicability checks; since during
985 * these checks it's sometime possible to have inference variables on
986 * the actual argument types list, the method applicability check must be
987 * extended so that inference variables are 'opened' as needed.
988 */
989 class MethodReferenceCheck extends AbstractMethodCheck {
990
991 InferenceContext pendingInferenceContext;
992
993 MethodReferenceCheck(InferenceContext pendingInferenceContext) {
994 this.pendingInferenceContext = pendingInferenceContext;
995 }
996
997 @Override
998 void checkArg(DiagnosticPosition pos, boolean varargs, Type actual, Type formal, DeferredAttrContext deferredAttrContext, Warner warn) {
999 ResultInfo mresult = methodCheckResult(varargs, formal, deferredAttrContext, warn);
1000 mresult.check(pos, actual);
1001 }
1002
1003 private ResultInfo methodCheckResult(final boolean varargsCheck, Type to,
1004 final DeferredAttr.DeferredAttrContext deferredAttrContext, Warner rsWarner) {
1005 CheckContext checkContext = new MethodCheckContext(!deferredAttrContext.phase.isBoxingRequired(), deferredAttrContext, rsWarner) {
1006 MethodCheckDiag methodDiag = varargsCheck ?
1007 MethodCheckDiag.VARARG_MISMATCH : MethodCheckDiag.ARG_MISMATCH;
1008
1009 @Override
1010 public boolean compatible(Type found, Type req, Warner warn) {
1011 found = pendingInferenceContext.asUndetVar(found);
1012 if (found.hasTag(UNDETVAR) && req.isPrimitive()) {
1013 req = types.boxedClass(req).type;
1014 }
1015 return super.compatible(found, req, warn);
1016 }
1017
1018 @Override
1019 public void report(DiagnosticPosition pos, JCDiagnostic details) {
1020 reportMC(pos, methodDiag, deferredAttrContext.inferenceContext, details);
1021 }
1022 };
1023 return new MethodResultInfo(to, checkContext);
1024 }
1025
1026 @Override
1027 public MethodCheck mostSpecificCheck(List<Type> actuals) {
1028 return new MostSpecificCheck(actuals);
1029 }
1030
1031 @Override
1032 public String toString() {
1033 return "MethodReferenceCheck";
1034 }
1035 }
1036
1037 /**
1038 * Check context to be used during method applicability checks. A method check
1039 * context might contain inference variables.
1040 */
1041 abstract class MethodCheckContext implements CheckContext {
1042
1043 boolean strict;
1044 DeferredAttrContext deferredAttrContext;
1045 Warner rsWarner;
1046
1047 public MethodCheckContext(boolean strict, DeferredAttrContext deferredAttrContext, Warner rsWarner) {
1048 this.strict = strict;
1049 this.deferredAttrContext = deferredAttrContext;
1050 this.rsWarner = rsWarner;
1051 }
1052
1053 public boolean compatible(Type found, Type req, Warner warn) {
1054 InferenceContext inferenceContext = deferredAttrContext.inferenceContext;
1055 return strict ?
1056 types.isSubtypeUnchecked(inferenceContext.asUndetVar(found), inferenceContext.asUndetVar(req), warn) :
1057 types.isConvertible(inferenceContext.asUndetVar(found), inferenceContext.asUndetVar(req), warn);
1058 }
1059
1060 public void report(DiagnosticPosition pos, JCDiagnostic details) {
1061 throw new InapplicableMethodException(details, Resolve.this.dumpStacktraceOnError);
1062 }
1063
1064 public Warner checkWarner(DiagnosticPosition pos, Type found, Type req) {
1065 return rsWarner;
1066 }
1067
1068 public InferenceContext inferenceContext() {
1069 return deferredAttrContext.inferenceContext;
1070 }
1071
1072 public DeferredAttrContext deferredAttrContext() {
1073 return deferredAttrContext;
1074 }
1075
1076 @Override
1077 public String toString() {
1078 return "MethodCheckContext";
1079 }
1080 }
1081
1082 /**
1083 * ResultInfo class to be used during method applicability checks. Check
1084 * for deferred types goes through special path.
1085 */
1086 class MethodResultInfo extends ResultInfo {
1087
1088 public MethodResultInfo(Type pt, CheckContext checkContext) {
1089 attr.super(KindSelector.VAL, pt, checkContext);
1090 }
1091
1092 @Override
1093 protected Type check(DiagnosticPosition pos, Type found) {
1094 if (found.hasTag(DEFERRED)) {
1095 DeferredType dt = (DeferredType)found;
1096 return dt.check(this);
1097 } else {
1098 Type uResult = U(found);
1099 Type capturedType = pos == null || pos.getTree() == null ?
1100 types.capture(uResult) :
1101 checkContext.inferenceContext()
1102 .cachedCapture(pos.getTree(), uResult, true);
1103 return super.check(pos, chk.checkNonVoid(pos, capturedType));
1104 }
1105 }
1106
1107 /**
1108 * javac has a long-standing 'simplification' (see 6391995):
1109 * given an actual argument type, the method check is performed
1110 * on its upper bound. This leads to inconsistencies when an
1111 * argument type is checked against itself. For example, given
1112 * a type-variable T, it is not true that {@code U(T) <: T},
1113 * so we need to guard against that.
1114 */
1115 private Type U(Type found) {
1116 return found == pt ?
1117 found : types.cvarUpperBound(found);
1118 }
1119
1120 @Override
1121 protected MethodResultInfo dup(Type newPt) {
1122 return new MethodResultInfo(newPt, checkContext);
1123 }
1124
1125 @Override
1126 protected ResultInfo dup(CheckContext newContext) {
1127 return new MethodResultInfo(pt, newContext);
1128 }
1129
1130 @Override
1131 protected ResultInfo dup(Type newPt, CheckContext newContext) {
1132 return new MethodResultInfo(newPt, newContext);
1133 }
1134 }
1135
1136 /**
1137 * Most specific method applicability routine. Given a list of actual types A,
1138 * a list of formal types F1, and a list of formal types F2, the routine determines
1139 * as to whether the types in F1 can be considered more specific than those in F2 w.r.t.
1140 * argument types A.
1141 */
1142 class MostSpecificCheck implements MethodCheck {
1143
1144 List<Type> actuals;
1145
1146 MostSpecificCheck(List<Type> actuals) {
1147 this.actuals = actuals;
1148 }
1149
1150 @Override
1151 public void argumentsAcceptable(final Env<AttrContext> env,
1152 DeferredAttrContext deferredAttrContext,
1153 List<Type> formals1,
1154 List<Type> formals2,
1155 Warner warn) {
1156 formals2 = adjustArgs(formals2, deferredAttrContext.msym, formals1.length(), deferredAttrContext.phase.isVarargsRequired());
1157 while (formals2.nonEmpty()) {
1158 ResultInfo mresult = methodCheckResult(formals2.head, deferredAttrContext, warn, actuals.head);
1159 mresult.check(null, formals1.head);
1160 formals1 = formals1.tail;
1161 formals2 = formals2.tail;
1162 actuals = actuals.isEmpty() ? actuals : actuals.tail;
1163 }
1164 }
1165
1166 /**
1167 * Create a method check context to be used during the most specific applicability check
1168 */
1169 ResultInfo methodCheckResult(Type to, DeferredAttr.DeferredAttrContext deferredAttrContext,
1170 Warner rsWarner, Type actual) {
1171 return attr.new ResultInfo(KindSelector.VAL, to,
1172 new MostSpecificCheckContext(deferredAttrContext, rsWarner, actual));
1173 }
1174
1175 /**
1176 * Subclass of method check context class that implements most specific
1177 * method conversion. If the actual type under analysis is a deferred type
1178 * a full blown structural analysis is carried out.
1179 */
1180 class MostSpecificCheckContext extends MethodCheckContext {
1181
1182 Type actual;
1183
1184 public MostSpecificCheckContext(DeferredAttrContext deferredAttrContext, Warner rsWarner, Type actual) {
1185 super(true, deferredAttrContext, rsWarner);
1186 this.actual = actual;
1187 }
1188
1189 public boolean compatible(Type found, Type req, Warner warn) {
1190 if (unrelatedFunctionalInterfaces(found, req) &&
1191 (actual != null && actual.getTag() == DEFERRED)) {
1192 DeferredType dt = (DeferredType) actual;
1193 JCTree speculativeTree = dt.speculativeTree(deferredAttrContext);
1194 if (speculativeTree != deferredAttr.stuckTree) {
1195 return functionalInterfaceMostSpecific(found, req, speculativeTree);
1196 }
1197 }
1198 return compatibleBySubtyping(found, req);
1199 }
1200
1201 private boolean compatibleBySubtyping(Type found, Type req) {
1202 if (!strict && found.isPrimitive() != req.isPrimitive()) {
1203 found = found.isPrimitive() ? types.boxedClass(found).type : types.unboxedType(found);
1204 }
1205 return types.isSubtypeNoCapture(found, deferredAttrContext.inferenceContext.asUndetVar(req));
1206 }
1207
1208 /** Whether {@code t} and {@code s} are unrelated functional interface types. */
1209 private boolean unrelatedFunctionalInterfaces(Type t, Type s) {
1210 return types.isFunctionalInterface(t.tsym) &&
1211 types.isFunctionalInterface(s.tsym) &&
1212 unrelatedInterfaces(t, s);
1213 }
1214
1215 /** Whether {@code t} and {@code s} are unrelated interface types; recurs on intersections. **/
1216 private boolean unrelatedInterfaces(Type t, Type s) {
1217 if (t.isCompound()) {
1218 for (Type ti : types.interfaces(t)) {
1219 if (!unrelatedInterfaces(ti, s)) {
1220 return false;
1221 }
1222 }
1223 return true;
1224 } else if (s.isCompound()) {
1225 for (Type si : types.interfaces(s)) {
1226 if (!unrelatedInterfaces(t, si)) {
1227 return false;
1228 }
1229 }
1230 return true;
1231 } else {
1232 return types.asSuper(t, s.tsym) == null && types.asSuper(s, t.tsym) == null;
1233 }
1234 }
1235
1236 /** Parameters {@code t} and {@code s} are unrelated functional interface types. */
1237 private boolean functionalInterfaceMostSpecific(Type t, Type s, JCTree tree) {
1238 Type tDesc;
1239 Type tDescNoCapture;
1240 Type sDesc;
1241 try {
1242 tDesc = types.findDescriptorType(types.capture(t));
1243 tDescNoCapture = types.findDescriptorType(t);
1244 sDesc = types.findDescriptorType(s);
1245 } catch (Types.FunctionDescriptorLookupError ex) {
1246 // don't report, a more meaningful error should be reported upstream
1247 return false;
1248 }
1249 final List<Type> tTypeParams = tDesc.getTypeArguments();
1250 final List<Type> tTypeParamsNoCapture = tDescNoCapture.getTypeArguments();
1251 final List<Type> sTypeParams = sDesc.getTypeArguments();
1252
1253 // compare type parameters
1254 if (tDesc.hasTag(FORALL) && !types.hasSameBounds((ForAll) tDesc, (ForAll) tDescNoCapture)) {
1255 return false;
1256 }
1257 // can't use Types.hasSameBounds on sDesc because bounds may have ivars
1258 List<Type> tIter = tTypeParams;
1259 List<Type> sIter = sTypeParams;
1260 while (tIter.nonEmpty() && sIter.nonEmpty()) {
1261 Type tBound = tIter.head.getUpperBound();
1262 Type sBound = types.subst(sIter.head.getUpperBound(), sTypeParams, tTypeParams);
1263 if (tBound.containsAny(tTypeParams) && inferenceContext().free(sBound)) {
1264 return false;
1265 }
1266 if (!types.isSameType(tBound, inferenceContext().asUndetVar(sBound))) {
1267 return false;
1268 }
1269 tIter = tIter.tail;
1270 sIter = sIter.tail;
1271 }
1272 if (!tIter.isEmpty() || !sIter.isEmpty()) {
1273 return false;
1274 }
1275
1276 // compare parameters
1277 List<Type> tParams = tDesc.getParameterTypes();
1278 List<Type> tParamsNoCapture = tDescNoCapture.getParameterTypes();
1279 List<Type> sParams = sDesc.getParameterTypes();
1280 while (tParams.nonEmpty() && tParamsNoCapture.nonEmpty() && sParams.nonEmpty()) {
1281 Type tParam = tParams.head;
1282 Type tParamNoCapture = types.subst(tParamsNoCapture.head, tTypeParamsNoCapture, tTypeParams);
1283 Type sParam = types.subst(sParams.head, sTypeParams, tTypeParams);
1284 if (tParam.containsAny(tTypeParams) && inferenceContext().free(sParam)) {
1285 return false;
1286 }
1287 if (!types.isSubtype(inferenceContext().asUndetVar(sParam), tParam)) {
1288 return false;
1289 }
1290 if (!types.isSameType(tParamNoCapture, inferenceContext().asUndetVar(sParam))) {
1291 return false;
1292 }
1293 tParams = tParams.tail;
1294 tParamsNoCapture = tParamsNoCapture.tail;
1295 sParams = sParams.tail;
1296 }
1297 if (!tParams.isEmpty() || !tParamsNoCapture.isEmpty() || !sParams.isEmpty()) {
1298 return false;
1299 }
1300
1301 // compare returns
1302 Type tRet = tDesc.getReturnType();
1303 Type sRet = types.subst(sDesc.getReturnType(), sTypeParams, tTypeParams);
1304 if (tRet.containsAny(tTypeParams) && inferenceContext().free(sRet)) {
1305 return false;
1306 }
1307 MostSpecificFunctionReturnChecker msc = new MostSpecificFunctionReturnChecker(tRet, sRet);
1308 msc.scan(tree);
1309 return msc.result;
1310 }
1311
1312 /**
1313 * Tests whether one functional interface type can be considered more specific
1314 * than another unrelated functional interface type for the scanned expression.
1315 */
1316 class MostSpecificFunctionReturnChecker extends DeferredAttr.PolyScanner {
1317
1318 final Type tRet;
1319 final Type sRet;
1320 boolean result;
1321
1322 /** Parameters {@code t} and {@code s} are unrelated functional interface types. */
1323 MostSpecificFunctionReturnChecker(Type tRet, Type sRet) {
1324 this.tRet = tRet;
1325 this.sRet = sRet;
1326 result = true;
1327 }
1328
1329 @Override
1330 void skip(JCTree tree) {
1331 result = false;
1332 }
1333
1334 @Override
1335 public void visitConditional(JCConditional tree) {
1336 scan(asExpr(tree.truepart));
1337 scan(asExpr(tree.falsepart));
1338 }
1339
1340 @Override
1341 public void visitReference(JCMemberReference tree) {
1342 if (sRet.hasTag(VOID)) {
1343 // do nothing
1344 } else if (tRet.hasTag(VOID)) {
1345 result = false;
1346 } else if (tRet.isPrimitive() != sRet.isPrimitive()) {
1347 boolean retValIsPrimitive =
1348 tree.refPolyKind == PolyKind.STANDALONE &&
1349 tree.sym.type.getReturnType().isPrimitive();
1350 result &= (retValIsPrimitive == tRet.isPrimitive()) &&
1351 (retValIsPrimitive != sRet.isPrimitive());
1352 } else {
1353 result &= compatibleBySubtyping(tRet, sRet);
1354 }
1355 }
1356
1357 @Override
1358 public void visitParens(JCParens tree) {
1359 scan(asExpr(tree.expr));
1360 }
1361
1362 @Override
1363 public void visitLambda(JCLambda tree) {
1364 if (sRet.hasTag(VOID)) {
1365 // do nothing
1366 } else if (tRet.hasTag(VOID)) {
1367 result = false;
1368 } else {
1369 List<JCExpression> lambdaResults = lambdaResults(tree);
1370 if (!lambdaResults.isEmpty() && unrelatedFunctionalInterfaces(tRet, sRet)) {
1371 for (JCExpression expr : lambdaResults) {
1372 result &= functionalInterfaceMostSpecific(tRet, sRet, expr);
1373 }
1374 } else if (!lambdaResults.isEmpty() && tRet.isPrimitive() != sRet.isPrimitive()) {
1375 for (JCExpression expr : lambdaResults) {
1376 boolean retValIsPrimitive = expr.isStandalone() && expr.type.isPrimitive();
1377 result &= (retValIsPrimitive == tRet.isPrimitive()) &&
1378 (retValIsPrimitive != sRet.isPrimitive());
1379 }
1380 } else {
1381 result &= compatibleBySubtyping(tRet, sRet);
1382 }
1383 }
1384 }
1385 //where
1386
1387 private List<JCExpression> lambdaResults(JCLambda lambda) {
1388 if (lambda.getBodyKind() == JCTree.JCLambda.BodyKind.EXPRESSION) {
1389 return List.of(asExpr((JCExpression) lambda.body));
1390 } else {
1391 final ListBuffer<JCExpression> buffer = new ListBuffer<>();
1392 DeferredAttr.LambdaReturnScanner lambdaScanner =
1393 new DeferredAttr.LambdaReturnScanner() {
1394 @Override
1395 public void visitReturn(JCReturn tree) {
1396 if (tree.expr != null) {
1397 buffer.append(asExpr(tree.expr));
1398 }
1399 }
1400 };
1401 lambdaScanner.scan(lambda.body);
1402 return buffer.toList();
1403 }
1404 }
1405
1406 private JCExpression asExpr(JCExpression expr) {
1407 if (expr.type.hasTag(DEFERRED)) {
1408 JCTree speculativeTree = ((DeferredType)expr.type).speculativeTree(deferredAttrContext);
1409 if (speculativeTree != deferredAttr.stuckTree) {
1410 expr = (JCExpression)speculativeTree;
1411 }
1412 }
1413 return expr;
1414 }
1415 }
1416
1417 }
1418
1419 public MethodCheck mostSpecificCheck(List<Type> actuals) {
1420 Assert.error("Cannot get here!");
1421 return null;
1422 }
1423 }
1424
1425 public static class InapplicableMethodException extends CompilerInternalException {
1426 private static final long serialVersionUID = 0;
1427
1428 transient JCDiagnostic diagnostic;
1429
1430 InapplicableMethodException(JCDiagnostic diag, boolean dumpStackTraceOnError) {
1431 super(dumpStackTraceOnError);
1432 this.diagnostic = diag;
1433 }
1434
1435 public JCDiagnostic getDiagnostic() {
1436 return diagnostic;
1437 }
1438 }
1439
1440 /* ***************************************************************************
1441 * Symbol lookup
1442 * the following naming conventions for arguments are used
1443 *
1444 * env is the environment where the symbol was mentioned
1445 * site is the type of which the symbol is a member
1446 * name is the symbol's name
1447 * if no arguments are given
1448 * argtypes are the value arguments, if we search for a method
1449 *
1450 * If no symbol was found, a ResolveError detailing the problem is returned.
1451 ****************************************************************************/
1452
1453 /** Find field. Synthetic fields are always skipped.
1454 * @param env The current environment.
1455 * @param site The original type from where the selection takes place.
1456 * @param name The name of the field.
1457 * @param c The class to search for the field. This is always
1458 * a superclass or implemented interface of site's class.
1459 */
1460 Symbol findField(Env<AttrContext> env,
1461 Type site,
1462 Name name,
1463 TypeSymbol c) {
1464 while (c.type.hasTag(TYPEVAR))
1465 c = c.type.getUpperBound().tsym;
1466 Symbol bestSoFar = varNotFound;
1467 Symbol sym;
1468 for (Symbol s : c.members().getSymbolsByName(name)) {
1469 if (s.kind == VAR && (s.flags_field & SYNTHETIC) == 0) {
1470 return isAccessible(env, site, s)
1471 ? s : new AccessError(env, site, s);
1472 }
1473 }
1474 Type st = types.supertype(c.type);
1475 if (st != null && (st.hasTag(CLASS) || st.hasTag(TYPEVAR))) {
1476 sym = findField(env, site, name, st.tsym);
1477 bestSoFar = bestOf(bestSoFar, sym);
1478 }
1479 for (List<Type> l = types.interfaces(c.type);
1480 bestSoFar.kind != AMBIGUOUS && l.nonEmpty();
1481 l = l.tail) {
1482 sym = findField(env, site, name, l.head.tsym);
1483 if (bestSoFar.exists() && sym.exists() &&
1484 sym.owner != bestSoFar.owner)
1485 bestSoFar = new AmbiguityError(bestSoFar, sym);
1486 else
1487 bestSoFar = bestOf(bestSoFar, sym);
1488 }
1489 return bestSoFar;
1490 }
1491
1492 /** Resolve a field identifier, throw a fatal error if not found.
1493 * @param pos The position to use for error reporting.
1494 * @param env The environment current at the method invocation.
1495 * @param site The type of the qualifying expression, in which
1496 * identifier is searched.
1497 * @param name The identifier's name.
1498 */
1499 public VarSymbol resolveInternalField(DiagnosticPosition pos, Env<AttrContext> env,
1500 Type site, Name name) {
1501 Symbol sym = findField(env, site, name, site.tsym);
1502 if (sym.kind == VAR) return (VarSymbol)sym;
1503 else throw new FatalError(
1504 diags.fragment(Fragments.FatalErrCantLocateField(name)));
1505 }
1506
1507 /** Find unqualified variable or field with given name.
1508 * Synthetic fields always skipped.
1509 * @param pos The position to use for error reporting.
1510 * @param env The current environment.
1511 * @param name The name of the variable or field.
1512 */
1513 Symbol findVar(DiagnosticPosition pos, Env<AttrContext> env, Name name) {
1514 Symbol bestSoFar = varNotFound;
1515 Env<AttrContext> env1 = env;
1516 boolean staticOnly = false;
1517 while (env1.outer != null) {
1518 Symbol sym = null;
1519 for (Symbol s : env1.info.scope.getSymbolsByName(name)) {
1520 if (s.kind == VAR && (s.flags_field & SYNTHETIC) == 0) {
1521 sym = s;
1522 if (staticOnly) {
1523 return new StaticError(sym);
1524 }
1525 break;
1526 }
1527 }
1528 if (isStatic(env1)) staticOnly = true;
1529 if (sym == null) {
1530 sym = findField(env1, env1.enclClass.sym.type, name, env1.enclClass.sym);
1531 }
1532 if (sym.exists()) {
1533 if (sym.kind == VAR &&
1534 sym.owner.kind == TYP &&
1535 (sym.flags() & STATIC) == 0) {
1536 if (staticOnly)
1537 return new StaticError(sym);
1538 if (env1.info.ctorPrologue && !isAllowedEarlyReference(pos, env1, (VarSymbol)sym)) {
1539 if (!env.tree.hasTag(ASSIGN) || !TreeInfo.isIdentOrThisDotIdent(((JCAssign)env.tree).lhs)) {
1540 return new RefBeforeCtorCalledError(sym);
1541 }
1542 }
1543 }
1544 return sym;
1545 } else {
1546 bestSoFar = bestOf(bestSoFar, sym);
1547 }
1548
1549 if ((env1.enclClass.sym.flags() & STATIC) != 0) staticOnly = true;
1550 env1 = env1.outer;
1551 }
1552
1553 Symbol sym = findField(env, syms.predefClass.type, name, syms.predefClass);
1554 if (sym.exists())
1555 return sym;
1556 if (bestSoFar.exists())
1557 return bestSoFar;
1558
1559 Symbol origin = null;
1560 for (Scope sc : new Scope[] { env.toplevel.namedImportScope, env.toplevel.starImportScope }) {
1561 for (Symbol currentSymbol : sc.getSymbolsByName(name)) {
1562 if (currentSymbol.kind != VAR)
1563 continue;
1564 // invariant: sym.kind == Symbol.Kind.VAR
1565 if (!bestSoFar.kind.isResolutionError() &&
1566 currentSymbol.owner != bestSoFar.owner)
1567 return new AmbiguityError(bestSoFar, currentSymbol);
1568 else if (!bestSoFar.kind.betterThan(VAR)) {
1569 origin = sc.getOrigin(currentSymbol).owner;
1570 bestSoFar = isAccessible(env, origin.type, currentSymbol)
1571 ? currentSymbol : new AccessError(env, origin.type, currentSymbol);
1572 }
1573 }
1574 if (bestSoFar.exists()) break;
1575 }
1576 if (bestSoFar.kind == VAR && bestSoFar.owner.type != origin.type)
1577 return bestSoFar.clone(origin);
1578 else
1579 return bestSoFar;
1580 }
1581
1582 Warner noteWarner = new Warner();
1583
1584 /** Select the best method for a call site among two choices.
1585 * @param env The current environment.
1586 * @param site The original type from where the
1587 * selection takes place.
1588 * @param argtypes The invocation's value arguments,
1589 * @param typeargtypes The invocation's type arguments,
1590 * @param sym Proposed new best match.
1591 * @param bestSoFar Previously found best match.
1592 * @param allowBoxing Allow boxing conversions of arguments.
1593 * @param useVarargs Box trailing arguments into an array for varargs.
1594 */
1595 @SuppressWarnings("fallthrough")
1596 Symbol selectBest(Env<AttrContext> env,
1597 Type site,
1598 List<Type> argtypes,
1599 List<Type> typeargtypes,
1600 Symbol sym,
1601 Symbol bestSoFar,
1602 boolean allowBoxing,
1603 boolean useVarargs) {
1604 if (sym.kind == ERR ||
1605 (site.tsym != sym.owner && !sym.isInheritedIn(site.tsym, types)) ||
1606 !notOverriddenIn(site, sym)) {
1607 return bestSoFar;
1608 } else if (useVarargs && (sym.flags() & VARARGS) == 0) {
1609 return bestSoFar.kind.isResolutionError() ?
1610 new BadVarargsMethod((ResolveError)bestSoFar.baseSymbol()) :
1611 bestSoFar;
1612 }
1613 Assert.check(!sym.kind.isResolutionError());
1614 try {
1615 types.noWarnings.clear();
1616 Type mt = rawInstantiate(env, site, sym, null, argtypes, typeargtypes,
1617 allowBoxing, useVarargs, types.noWarnings);
1618 currentResolutionContext.addApplicableCandidate(sym, mt);
1619 } catch (InapplicableMethodException ex) {
1620 currentResolutionContext.addInapplicableCandidate(sym, ex.getDiagnostic());
1621 // Currently, an InapplicableMethodException occurs.
1622 // If bestSoFar.kind was ABSENT_MTH, return an InapplicableSymbolError(kind is WRONG_MTH).
1623 // If bestSoFar.kind was HIDDEN(AccessError)/WRONG_MTH/WRONG_MTHS, return an InapplicableSymbolsError(kind is WRONG_MTHS).
1624 // See JDK-8255968 for more information.
1625 switch (bestSoFar.kind) {
1626 case ABSENT_MTH:
1627 return new InapplicableSymbolError(currentResolutionContext);
1628 case HIDDEN:
1629 if (bestSoFar instanceof AccessError accessError) {
1630 // Add the JCDiagnostic of previous AccessError to the currentResolutionContext
1631 // and construct InapplicableSymbolsError.
1632 // Intentionally fallthrough.
1633 currentResolutionContext.addInapplicableCandidate(accessError.sym,
1634 accessError.getDiagnostic(JCDiagnostic.DiagnosticType.FRAGMENT, null, null, site, null, argtypes, typeargtypes));
1635 } else {
1636 return bestSoFar;
1637 }
1638 case WRONG_MTH:
1639 bestSoFar = new InapplicableSymbolsError(currentResolutionContext);
1640 default:
1641 return bestSoFar;
1642 }
1643 }
1644 if (!isAccessible(env, site, sym)) {
1645 AccessError curAccessError = new AccessError(env, site, sym);
1646 JCDiagnostic curDiagnostic = curAccessError.getDiagnostic(JCDiagnostic.DiagnosticType.FRAGMENT, null, null, site, null, argtypes, typeargtypes);
1647 // Currently, an AccessError occurs.
1648 // If bestSoFar.kind was ABSENT_MTH, return an AccessError(kind is HIDDEN).
1649 // If bestSoFar.kind was HIDDEN(AccessError), WRONG_MTH, WRONG_MTHS, return an InapplicableSymbolsError(kind is WRONG_MTHS).
1650 // See JDK-8255968 for more information.
1651 if (bestSoFar.kind == ABSENT_MTH) {
1652 bestSoFar = curAccessError;
1653 } else if (bestSoFar.kind == WRONG_MTH) {
1654 // Add the JCDiagnostic of current AccessError to the currentResolutionContext
1655 // and construct InapplicableSymbolsError.
1656 currentResolutionContext.addInapplicableCandidate(sym, curDiagnostic);
1657 bestSoFar = new InapplicableSymbolsError(currentResolutionContext);
1658 } else if (bestSoFar.kind == WRONG_MTHS) {
1659 // Add the JCDiagnostic of current AccessError to the currentResolutionContext
1660 currentResolutionContext.addInapplicableCandidate(sym, curDiagnostic);
1661 } else if (bestSoFar.kind == HIDDEN && bestSoFar instanceof AccessError accessError) {
1662 // Add the JCDiagnostics of previous and current AccessError to the currentResolutionContext
1663 // and construct InapplicableSymbolsError.
1664 currentResolutionContext.addInapplicableCandidate(accessError.sym,
1665 accessError.getDiagnostic(JCDiagnostic.DiagnosticType.FRAGMENT, null, null, site, null, argtypes, typeargtypes));
1666 currentResolutionContext.addInapplicableCandidate(sym, curDiagnostic);
1667 bestSoFar = new InapplicableSymbolsError(currentResolutionContext);
1668 }
1669 return bestSoFar;
1670 }
1671 return (bestSoFar.kind.isResolutionError() && bestSoFar.kind != AMBIGUOUS)
1672 ? sym
1673 : mostSpecific(argtypes, sym, bestSoFar, env, site, useVarargs);
1674 }
1675
1676 /* Return the most specific of the two methods for a call,
1677 * given that both are accessible and applicable.
1678 * @param m1 A new candidate for most specific.
1679 * @param m2 The previous most specific candidate.
1680 * @param env The current environment.
1681 * @param site The original type from where the selection
1682 * takes place.
1683 * @param allowBoxing Allow boxing conversions of arguments.
1684 * @param useVarargs Box trailing arguments into an array for varargs.
1685 */
1686 Symbol mostSpecific(List<Type> argtypes, Symbol m1,
1687 Symbol m2,
1688 Env<AttrContext> env,
1689 final Type site,
1690 boolean useVarargs) {
1691 switch (m2.kind) {
1692 case MTH:
1693 if (m1 == m2) return m1;
1694 boolean m1SignatureMoreSpecific =
1695 signatureMoreSpecific(argtypes, env, site, m1, m2, useVarargs);
1696 boolean m2SignatureMoreSpecific =
1697 signatureMoreSpecific(argtypes, env, site, m2, m1, useVarargs);
1698 if (m1SignatureMoreSpecific && m2SignatureMoreSpecific) {
1699 Type mt1 = types.memberType(site, m1);
1700 Type mt2 = types.memberType(site, m2);
1701 if (!types.overrideEquivalent(mt1, mt2))
1702 return ambiguityError(m1, m2);
1703
1704 // same signature; select (a) the non-bridge method, or
1705 // (b) the one that overrides the other, or (c) the concrete
1706 // one, or (d) merge both abstract signatures
1707 if ((m1.flags() & BRIDGE) != (m2.flags() & BRIDGE))
1708 return ((m1.flags() & BRIDGE) != 0) ? m2 : m1;
1709
1710 if (m1.baseSymbol() == m2.baseSymbol()) {
1711 // this is the same imported symbol which has been cloned twice.
1712 // Return the first one (either will do).
1713 return m1;
1714 }
1715
1716 // if one overrides or hides the other, use it
1717 TypeSymbol m1Owner = (TypeSymbol)m1.owner;
1718 TypeSymbol m2Owner = (TypeSymbol)m2.owner;
1719 // the two owners can never be the same if the target methods are compiled from source,
1720 // but we need to protect against cases where the methods are defined in some classfile
1721 // and make sure we issue an ambiguity error accordingly (by skipping the logic below).
1722 if (m1Owner != m2Owner) {
1723 if (types.asSuper(m1Owner.type, m2Owner) != null &&
1724 ((m1.owner.flags_field & INTERFACE) == 0 ||
1725 (m2.owner.flags_field & INTERFACE) != 0) &&
1726 m1.overrides(m2, m1Owner, types, false))
1727 return m1;
1728 if (types.asSuper(m2Owner.type, m1Owner) != null &&
1729 ((m2.owner.flags_field & INTERFACE) == 0 ||
1730 (m1.owner.flags_field & INTERFACE) != 0) &&
1731 m2.overrides(m1, m2Owner, types, false))
1732 return m2;
1733 }
1734 boolean m1Abstract = (m1.flags() & ABSTRACT) != 0;
1735 boolean m2Abstract = (m2.flags() & ABSTRACT) != 0;
1736 if (m1Abstract && !m2Abstract) return m2;
1737 if (m2Abstract && !m1Abstract) return m1;
1738 // both abstract or both concrete
1739 return ambiguityError(m1, m2);
1740 }
1741 if (m1SignatureMoreSpecific) return m1;
1742 if (m2SignatureMoreSpecific) return m2;
1743 return ambiguityError(m1, m2);
1744 case AMBIGUOUS:
1745 //compare m1 to ambiguous methods in m2
1746 AmbiguityError e = (AmbiguityError)m2.baseSymbol();
1747 boolean m1MoreSpecificThanAnyAmbiguous = true;
1748 boolean allAmbiguousMoreSpecificThanM1 = true;
1749 for (Symbol s : e.ambiguousSyms) {
1750 Symbol moreSpecific = mostSpecific(argtypes, m1, s, env, site, useVarargs);
1751 m1MoreSpecificThanAnyAmbiguous &= moreSpecific == m1;
1752 allAmbiguousMoreSpecificThanM1 &= moreSpecific == s;
1753 }
1754 if (m1MoreSpecificThanAnyAmbiguous)
1755 return m1;
1756 //if m1 is more specific than some ambiguous methods, but other ambiguous methods are
1757 //more specific than m1, add it as a new ambiguous method:
1758 if (!allAmbiguousMoreSpecificThanM1)
1759 e.addAmbiguousSymbol(m1);
1760 return e;
1761 default:
1762 throw new AssertionError();
1763 }
1764 }
1765 //where
1766 private boolean signatureMoreSpecific(List<Type> actuals, Env<AttrContext> env, Type site, Symbol m1, Symbol m2, boolean useVarargs) {
1767 noteWarner.clear();
1768 int maxLength = Math.max(
1769 Math.max(m1.type.getParameterTypes().length(), actuals.length()),
1770 m2.type.getParameterTypes().length());
1771 MethodResolutionContext prevResolutionContext = currentResolutionContext;
1772 try {
1773 currentResolutionContext = new MethodResolutionContext();
1774 currentResolutionContext.step = prevResolutionContext.step;
1775 currentResolutionContext.methodCheck =
1776 prevResolutionContext.methodCheck.mostSpecificCheck(actuals);
1777 Type mst = instantiate(env, site, m2, null,
1778 adjustArgs(types.cvarLowerBounds(types.memberType(site, m1).getParameterTypes()), m1, maxLength, useVarargs), null,
1779 false, useVarargs, noteWarner);
1780 return mst != null &&
1781 !noteWarner.hasLint(Lint.LintCategory.UNCHECKED);
1782 } finally {
1783 currentResolutionContext = prevResolutionContext;
1784 }
1785 }
1786
1787 List<Type> adjustArgs(List<Type> args, Symbol msym, int length, boolean allowVarargs) {
1788 if ((msym.flags() & VARARGS) != 0 && allowVarargs) {
1789 Type varargsElem = types.elemtype(args.last());
1790 if (varargsElem == null) {
1791 Assert.error("Bad varargs = " + args.last() + " " + msym);
1792 }
1793 List<Type> newArgs = args.reverse().tail.prepend(varargsElem).reverse();
1794 while (newArgs.length() < length) {
1795 newArgs = newArgs.append(newArgs.last());
1796 }
1797 return newArgs;
1798 } else {
1799 return args;
1800 }
1801 }
1802 //where
1803 Symbol ambiguityError(Symbol m1, Symbol m2) {
1804 if (((m1.flags() | m2.flags()) & CLASH) != 0) {
1805 return (m1.flags() & CLASH) == 0 ? m1 : m2;
1806 } else {
1807 return new AmbiguityError(m1, m2);
1808 }
1809 }
1810
1811 Symbol findMethodInScope(Env<AttrContext> env,
1812 Type site,
1813 Name name,
1814 List<Type> argtypes,
1815 List<Type> typeargtypes,
1816 Scope sc,
1817 Symbol bestSoFar,
1818 boolean allowBoxing,
1819 boolean useVarargs,
1820 boolean abstractok) {
1821 for (Symbol s : sc.getSymbolsByName(name, new LookupFilter(abstractok))) {
1822 bestSoFar = selectBest(env, site, argtypes, typeargtypes, s,
1823 bestSoFar, allowBoxing, useVarargs);
1824 }
1825 return bestSoFar;
1826 }
1827 //where
1828 class LookupFilter implements Predicate<Symbol> {
1829
1830 boolean abstractOk;
1831
1832 LookupFilter(boolean abstractOk) {
1833 this.abstractOk = abstractOk;
1834 }
1835
1836 @Override
1837 public boolean test(Symbol s) {
1838 long flags = s.flags();
1839 return s.kind == MTH &&
1840 (flags & SYNTHETIC) == 0 &&
1841 (abstractOk ||
1842 (flags & DEFAULT) != 0 ||
1843 (flags & ABSTRACT) == 0);
1844 }
1845 }
1846
1847 /** Find best qualified method matching given name, type and value
1848 * arguments.
1849 * @param env The current environment.
1850 * @param site The original type from where the selection
1851 * takes place.
1852 * @param name The method's name.
1853 * @param argtypes The method's value arguments.
1854 * @param typeargtypes The method's type arguments
1855 * @param allowBoxing Allow boxing conversions of arguments.
1856 * @param useVarargs Box trailing arguments into an array for varargs.
1857 */
1858 Symbol findMethod(Env<AttrContext> env,
1859 Type site,
1860 Name name,
1861 List<Type> argtypes,
1862 List<Type> typeargtypes,
1863 boolean allowBoxing,
1864 boolean useVarargs) {
1865 Symbol bestSoFar = methodNotFound;
1866 bestSoFar = findMethod(env,
1867 site,
1868 name,
1869 argtypes,
1870 typeargtypes,
1871 site.tsym.type,
1872 bestSoFar,
1873 allowBoxing,
1874 useVarargs);
1875 if (bestSoFar.kind == AMBIGUOUS) {
1876 AmbiguityError a_err = (AmbiguityError)bestSoFar.baseSymbol();
1877 bestSoFar = a_err.mergeAbstracts(site);
1878 }
1879 return bestSoFar;
1880 }
1881 // where
1882 private Symbol findMethod(Env<AttrContext> env,
1883 Type site,
1884 Name name,
1885 List<Type> argtypes,
1886 List<Type> typeargtypes,
1887 Type intype,
1888 Symbol bestSoFar,
1889 boolean allowBoxing,
1890 boolean useVarargs) {
1891 @SuppressWarnings({"unchecked","rawtypes"})
1892 List<Type>[] itypes = (List<Type>[])new List[] { List.<Type>nil(), List.<Type>nil() };
1893
1894 InterfaceLookupPhase iphase = InterfaceLookupPhase.ABSTRACT_OK;
1895 boolean isInterface = site.tsym.isInterface();
1896 for (TypeSymbol s : isInterface ? List.of(intype.tsym) : superclasses(intype)) {
1897 bestSoFar = findMethodInScope(env, site, name, argtypes, typeargtypes,
1898 s.members(), bestSoFar, allowBoxing, useVarargs, true);
1899 if (name == names.init) return bestSoFar;
1900 iphase = (iphase == null) ? null : iphase.update(s, this);
1901 if (iphase != null) {
1902 for (Type itype : types.interfaces(s.type)) {
1903 itypes[iphase.ordinal()] = types.union(types.closure(itype), itypes[iphase.ordinal()]);
1904 }
1905 }
1906 }
1907
1908 Symbol concrete = bestSoFar.kind.isValid() &&
1909 (bestSoFar.flags() & ABSTRACT) == 0 ?
1910 bestSoFar : methodNotFound;
1911
1912 for (InterfaceLookupPhase iphase2 : InterfaceLookupPhase.values()) {
1913 //keep searching for abstract methods
1914 for (Type itype : itypes[iphase2.ordinal()]) {
1915 if (!itype.isInterface()) continue; //skip j.l.Object (included by Types.closure())
1916 if (iphase2 == InterfaceLookupPhase.DEFAULT_OK &&
1917 (itype.tsym.flags() & DEFAULT) == 0) continue;
1918 bestSoFar = findMethodInScope(env, site, name, argtypes, typeargtypes,
1919 itype.tsym.members(), bestSoFar, allowBoxing, useVarargs, true);
1920 if (concrete != bestSoFar &&
1921 concrete.kind.isValid() &&
1922 bestSoFar.kind.isValid() &&
1923 types.isSubSignature(concrete.type, bestSoFar.type)) {
1924 //this is an hack - as javac does not do full membership checks
1925 //most specific ends up comparing abstract methods that might have
1926 //been implemented by some concrete method in a subclass and,
1927 //because of raw override, it is possible for an abstract method
1928 //to be more specific than the concrete method - so we need
1929 //to explicitly call that out (see CR 6178365)
1930 bestSoFar = concrete;
1931 }
1932 }
1933 }
1934 if (isInterface && bestSoFar.kind.isResolutionError()) {
1935 bestSoFar = findMethodInScope(env, site, name, argtypes, typeargtypes,
1936 syms.objectType.tsym.members(), bestSoFar, allowBoxing, useVarargs, true);
1937 if (bestSoFar.kind.isValid()) {
1938 Symbol baseSymbol = bestSoFar;
1939 bestSoFar = new MethodSymbol(bestSoFar.flags_field, bestSoFar.name, bestSoFar.type, intype.tsym) {
1940 @Override
1941 public Symbol baseSymbol() {
1942 return baseSymbol;
1943 }
1944 };
1945 }
1946 }
1947 return bestSoFar;
1948 }
1949
1950 enum InterfaceLookupPhase {
1951 ABSTRACT_OK() {
1952 @Override
1953 InterfaceLookupPhase update(Symbol s, Resolve rs) {
1954 //We should not look for abstract methods if receiver is a concrete class
1955 //(as concrete classes are expected to implement all abstracts coming
1956 //from superinterfaces)
1957 if ((s.flags() & (ABSTRACT | INTERFACE | ENUM)) != 0) {
1958 return this;
1959 } else {
1960 return DEFAULT_OK;
1961 }
1962 }
1963 },
1964 DEFAULT_OK() {
1965 @Override
1966 InterfaceLookupPhase update(Symbol s, Resolve rs) {
1967 return this;
1968 }
1969 };
1970
1971 abstract InterfaceLookupPhase update(Symbol s, Resolve rs);
1972 }
1973
1974 /**
1975 * Return an Iterable object to scan the superclasses of a given type.
1976 * It's crucial that the scan is done lazily, as we don't want to accidentally
1977 * access more supertypes than strictly needed (as this could trigger completion
1978 * errors if some of the not-needed supertypes are missing/ill-formed).
1979 */
1980 Iterable<TypeSymbol> superclasses(final Type intype) {
1981 return () -> new Iterator<TypeSymbol>() {
1982
1983 List<TypeSymbol> seen = List.nil();
1984 TypeSymbol currentSym = symbolFor(intype);
1985 TypeSymbol prevSym = null;
1986
1987 public boolean hasNext() {
1988 if (currentSym == syms.noSymbol) {
1989 currentSym = symbolFor(types.supertype(prevSym.type));
1990 }
1991 return currentSym != null;
1992 }
1993
1994 public TypeSymbol next() {
1995 prevSym = currentSym;
1996 currentSym = syms.noSymbol;
1997 Assert.check(prevSym != null || prevSym != syms.noSymbol);
1998 return prevSym;
1999 }
2000
2001 public void remove() {
2002 throw new UnsupportedOperationException();
2003 }
2004
2005 TypeSymbol symbolFor(Type t) {
2006 if (!t.hasTag(CLASS) &&
2007 !t.hasTag(TYPEVAR)) {
2008 return null;
2009 }
2010 t = types.skipTypeVars(t, false);
2011 if (seen.contains(t.tsym)) {
2012 //degenerate case in which we have a circular
2013 //class hierarchy - because of ill-formed classfiles
2014 return null;
2015 }
2016 seen = seen.prepend(t.tsym);
2017 return t.tsym;
2018 }
2019 };
2020 }
2021
2022 /** Find unqualified method matching given name, type and value arguments.
2023 * @param env The current environment.
2024 * @param name The method's name.
2025 * @param argtypes The method's value arguments.
2026 * @param typeargtypes The method's type arguments.
2027 * @param allowBoxing Allow boxing conversions of arguments.
2028 * @param useVarargs Box trailing arguments into an array for varargs.
2029 */
2030 Symbol findFun(Env<AttrContext> env, Name name,
2031 List<Type> argtypes, List<Type> typeargtypes,
2032 boolean allowBoxing, boolean useVarargs) {
2033 Symbol bestSoFar = methodNotFound;
2034 Env<AttrContext> env1 = env;
2035 boolean staticOnly = false;
2036 while (env1.outer != null) {
2037 if (isStatic(env1)) staticOnly = true;
2038 Assert.check(env1.info.preferredTreeForDiagnostics == null);
2039 env1.info.preferredTreeForDiagnostics = env.tree;
2040 try {
2041 Symbol sym = findMethod(
2042 env1, env1.enclClass.sym.type, name, argtypes, typeargtypes,
2043 allowBoxing, useVarargs);
2044 if (sym.exists()) {
2045 if (sym.kind == MTH &&
2046 sym.owner.kind == TYP &&
2047 (sym.flags() & STATIC) == 0) {
2048 if (staticOnly)
2049 return new StaticError(sym);
2050 if (env1.info.ctorPrologue && env1 == env)
2051 return new RefBeforeCtorCalledError(sym);
2052 }
2053 return sym;
2054 } else {
2055 bestSoFar = bestOf(bestSoFar, sym);
2056 }
2057 } finally {
2058 env1.info.preferredTreeForDiagnostics = null;
2059 }
2060 if ((env1.enclClass.sym.flags() & STATIC) != 0) staticOnly = true;
2061 env1 = env1.outer;
2062 }
2063
2064 Symbol sym = findMethod(env, syms.predefClass.type, name, argtypes,
2065 typeargtypes, allowBoxing, useVarargs);
2066 if (sym.exists())
2067 return sym;
2068
2069 for (Symbol currentSym : env.toplevel.namedImportScope.getSymbolsByName(name)) {
2070 Symbol origin = env.toplevel.namedImportScope.getOrigin(currentSym).owner;
2071 if (currentSym.kind == MTH) {
2072 if (currentSym.owner.type != origin.type)
2073 currentSym = currentSym.clone(origin);
2074 if (!isAccessible(env, origin.type, currentSym))
2075 currentSym = new AccessError(env, origin.type, currentSym);
2076 bestSoFar = selectBest(env, origin.type,
2077 argtypes, typeargtypes,
2078 currentSym, bestSoFar,
2079 allowBoxing, useVarargs);
2080 }
2081 }
2082 if (bestSoFar.exists())
2083 return bestSoFar;
2084
2085 for (Symbol currentSym : env.toplevel.starImportScope.getSymbolsByName(name)) {
2086 Symbol origin = env.toplevel.starImportScope.getOrigin(currentSym).owner;
2087 if (currentSym.kind == MTH) {
2088 if (currentSym.owner.type != origin.type)
2089 currentSym = currentSym.clone(origin);
2090 if (!isAccessible(env, origin.type, currentSym))
2091 currentSym = new AccessError(env, origin.type, currentSym);
2092 bestSoFar = selectBest(env, origin.type,
2093 argtypes, typeargtypes,
2094 currentSym, bestSoFar,
2095 allowBoxing, useVarargs);
2096 }
2097 }
2098 return bestSoFar;
2099 }
2100
2101 /** Load toplevel or member class with given fully qualified name and
2102 * verify that it is accessible.
2103 * @param env The current environment.
2104 * @param name The fully qualified name of the class to be loaded.
2105 */
2106 Symbol loadClass(Env<AttrContext> env, Name name, RecoveryLoadClass recoveryLoadClass) {
2107 try {
2108 ClassSymbol c = finder.loadClass(env.toplevel.modle, name);
2109 return isAccessible(env, c) ? c : new AccessError(env, null, c);
2110 } catch (ClassFinder.BadClassFile err) {
2111 return new BadClassFileError(err);
2112 } catch (CompletionFailure ex) {
2113 Symbol candidate = recoveryLoadClass.loadClass(env, name);
2114
2115 if (candidate != null) {
2116 return candidate;
2117 }
2118
2119 return typeNotFound;
2120 }
2121 }
2122
2123 public interface RecoveryLoadClass {
2124 Symbol loadClass(Env<AttrContext> env, Name name);
2125 }
2126
2127 private final RecoveryLoadClass noRecovery = (env, name) -> null;
2128
2129 private final RecoveryLoadClass doRecoveryLoadClass = new RecoveryLoadClass() {
2130 @Override public Symbol loadClass(Env<AttrContext> env, Name name) {
2131 List<Name> candidates = Convert.classCandidates(name);
2132 return lookupInvisibleSymbol(env, name,
2133 n -> () -> createCompoundIterator(candidates,
2134 c -> syms.getClassesForName(c)
2135 .iterator()),
2136 (ms, n) -> {
2137 for (Name candidate : candidates) {
2138 try {
2139 return finder.loadClass(ms, candidate);
2140 } catch (CompletionFailure cf) {
2141 //ignore
2142 }
2143 }
2144 return null;
2145 }, sym -> sym.kind == Kind.TYP, typeNotFound);
2146 }
2147 };
2148
2149 private final RecoveryLoadClass namedImportScopeRecovery = (env, name) -> {
2150 Scope importScope = env.toplevel.namedImportScope;
2151 Symbol existing = importScope.findFirst(Convert.shortName(name),
2152 sym -> sym.kind == TYP && sym.flatName() == name);
2153
2154 if (existing != null) {
2155 return new InvisibleSymbolError(env, true, existing);
2156 }
2157 return null;
2158 };
2159
2160 private final RecoveryLoadClass starImportScopeRecovery = (env, name) -> {
2161 Scope importScope = env.toplevel.starImportScope;
2162 Symbol existing = importScope.findFirst(Convert.shortName(name),
2163 sym -> sym.kind == TYP && sym.flatName() == name);
2164
2165 if (existing != null) {
2166 try {
2167 existing = finder.loadClass(existing.packge().modle, name);
2168
2169 return new InvisibleSymbolError(env, true, existing);
2170 } catch (CompletionFailure cf) {
2171 //ignore
2172 }
2173 }
2174
2175 return null;
2176 };
2177
2178 Symbol lookupPackage(Env<AttrContext> env, Name name) {
2179 PackageSymbol pack = syms.lookupPackage(env.toplevel.modle, name);
2180
2181 if (allowModules && isImportOnDemand(env, name)) {
2182 if (pack.members().isEmpty()) {
2183 return lookupInvisibleSymbol(env, name, syms::getPackagesForName, syms::enterPackage, sym -> {
2184 sym.complete();
2185 return !sym.members().isEmpty();
2186 }, pack);
2187 }
2188 }
2189
2190 return pack;
2191 }
2192
2193 private boolean isImportOnDemand(Env<AttrContext> env, Name name) {
2194 if (!env.tree.hasTag(IMPORT))
2195 return false;
2196
2197 JCTree qualid = ((JCImport) env.tree).qualid;
2198
2199 if (!qualid.hasTag(SELECT))
2200 return false;
2201
2202 if (TreeInfo.name(qualid) != names.asterisk)
2203 return false;
2204
2205 return TreeInfo.fullName(((JCFieldAccess) qualid).selected) == name;
2206 }
2207
2208 private <S extends Symbol> Symbol lookupInvisibleSymbol(Env<AttrContext> env,
2209 Name name,
2210 Function<Name, Iterable<S>> get,
2211 BiFunction<ModuleSymbol, Name, S> load,
2212 Predicate<S> validate,
2213 Symbol defaultResult) {
2214 //even if a class/package cannot be found in the current module and among packages in modules
2215 //it depends on that are exported for any or this module, the class/package may exist internally
2216 //in some of these modules, or may exist in a module on which this module does not depend.
2217 //Provide better diagnostic in such cases by looking for the class in any module:
2218 Iterable<? extends S> candidates = get.apply(name);
2219
2220 for (S sym : candidates) {
2221 if (validate.test(sym))
2222 return createInvisibleSymbolError(env, sym);
2223 }
2224
2225 Set<ModuleSymbol> recoverableModules = new HashSet<>(syms.getAllModules());
2226
2227 recoverableModules.add(syms.unnamedModule);
2228 recoverableModules.remove(env.toplevel.modle);
2229
2230 for (ModuleSymbol ms : recoverableModules) {
2231 //avoid overly eager completing classes from source-based modules, as those
2232 //may not be completable with the current compiler settings:
2233 if (ms.sourceLocation == null) {
2234 if (ms.classLocation == null) {
2235 ms = moduleFinder.findModule(ms);
2236 }
2237
2238 if (ms.kind != ERR) {
2239 S sym = load.apply(ms, name);
2240
2241 if (sym != null && validate.test(sym)) {
2242 return createInvisibleSymbolError(env, sym);
2243 }
2244 }
2245 }
2246 }
2247
2248 return defaultResult;
2249 }
2250
2251 private Symbol createInvisibleSymbolError(Env<AttrContext> env, Symbol sym) {
2252 if (symbolPackageVisible(env, sym)) {
2253 return new AccessError(env, null, sym);
2254 } else {
2255 return new InvisibleSymbolError(env, false, sym);
2256 }
2257 }
2258
2259 private boolean symbolPackageVisible(Env<AttrContext> env, Symbol sym) {
2260 ModuleSymbol envMod = env.toplevel.modle;
2261 PackageSymbol symPack = sym.packge();
2262 return envMod == symPack.modle ||
2263 envMod.visiblePackages.containsKey(symPack.fullname);
2264 }
2265
2266 /**
2267 * Find a type declared in a scope (not inherited). Return null
2268 * if none is found.
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 findImmediateMemberType(Env<AttrContext> env,
2278 Type site,
2279 Name name,
2280 TypeSymbol c) {
2281 for (Symbol sym : c.members().getSymbolsByName(name)) {
2282 if (sym.kind == TYP) {
2283 return isAccessible(env, site, sym)
2284 ? sym
2285 : new AccessError(env, site, sym);
2286 }
2287 }
2288 return typeNotFound;
2289 }
2290
2291 /** Find a member type inherited from a superclass or interface.
2292 * @param env The current environment.
2293 * @param site The original type from where the selection takes
2294 * place.
2295 * @param name The type's name.
2296 * @param c The class to search for the member type. This is
2297 * always a superclass or implemented interface of
2298 * site's class.
2299 */
2300 Symbol findInheritedMemberType(Env<AttrContext> env,
2301 Type site,
2302 Name name,
2303 TypeSymbol c) {
2304 Symbol bestSoFar = typeNotFound;
2305 Symbol sym;
2306 Type st = types.supertype(c.type);
2307 if (st != null && st.hasTag(CLASS)) {
2308 sym = findMemberType(env, site, name, st.tsym);
2309 bestSoFar = bestOf(bestSoFar, sym);
2310 }
2311 for (List<Type> l = types.interfaces(c.type);
2312 bestSoFar.kind != AMBIGUOUS && l.nonEmpty();
2313 l = l.tail) {
2314 sym = findMemberType(env, site, name, l.head.tsym);
2315 if (!bestSoFar.kind.isResolutionError() &&
2316 !sym.kind.isResolutionError() &&
2317 sym.owner != bestSoFar.owner)
2318 bestSoFar = new AmbiguityError(bestSoFar, sym);
2319 else
2320 bestSoFar = bestOf(bestSoFar, sym);
2321 }
2322 return bestSoFar;
2323 }
2324
2325 /** Find qualified member type.
2326 * @param env The current environment.
2327 * @param site The original type from where the selection takes
2328 * place.
2329 * @param name The type's name.
2330 * @param c The class to search for the member type. This is
2331 * always a superclass or implemented interface of
2332 * site's class.
2333 */
2334 Symbol findMemberType(Env<AttrContext> env,
2335 Type site,
2336 Name name,
2337 TypeSymbol c) {
2338 Symbol sym = findImmediateMemberType(env, site, name, c);
2339
2340 if (sym != typeNotFound)
2341 return sym;
2342
2343 return findInheritedMemberType(env, site, name, c);
2344
2345 }
2346
2347 /** Find a global type in given scope and load corresponding class.
2348 * @param env The current environment.
2349 * @param scope The scope in which to look for the type.
2350 * @param name The type's name.
2351 */
2352 Symbol findGlobalType(Env<AttrContext> env, Scope scope, Name name, RecoveryLoadClass recoveryLoadClass) {
2353 Symbol bestSoFar = typeNotFound;
2354 for (Symbol s : scope.getSymbolsByName(name)) {
2355 Symbol sym = loadClass(env, s.flatName(), recoveryLoadClass);
2356 if (bestSoFar.kind == TYP && sym.kind == TYP &&
2357 bestSoFar != sym)
2358 return new AmbiguityError(bestSoFar, sym);
2359 else
2360 bestSoFar = bestOf(bestSoFar, sym);
2361 }
2362 return bestSoFar;
2363 }
2364
2365 Symbol findTypeVar(Env<AttrContext> env, Name name, boolean staticOnly) {
2366 for (Symbol sym : env.info.scope.getSymbolsByName(name)) {
2367 if (sym.kind == TYP) {
2368 if (sym.type.hasTag(TYPEVAR) &&
2369 (staticOnly || (isStatic(env) && sym.owner.kind == TYP)))
2370 // if staticOnly is set, it means that we have recursed through a static declaration,
2371 // so type variable symbols should not be accessible. If staticOnly is unset, but
2372 // we are in a static declaration (field or method), we should not allow type-variables
2373 // defined in the enclosing class to "leak" into this context.
2374 return new StaticError(sym);
2375 return sym;
2376 }
2377 }
2378 return typeNotFound;
2379 }
2380
2381 /** Find an unqualified type symbol.
2382 * @param env The current environment.
2383 * @param name The type's name.
2384 */
2385 Symbol findType(Env<AttrContext> env, Name name) {
2386 if (name == names.empty)
2387 return typeNotFound; // do not allow inadvertent "lookup" of anonymous types
2388 Symbol bestSoFar = typeNotFound;
2389 Symbol sym;
2390 boolean staticOnly = false;
2391 for (Env<AttrContext> env1 = env; env1.outer != null; env1 = env1.outer) {
2392 // First, look for a type variable and the first member type
2393 final Symbol tyvar = findTypeVar(env1, name, staticOnly);
2394 if (isStatic(env1)) staticOnly = true;
2395 sym = findImmediateMemberType(env1, env1.enclClass.sym.type,
2396 name, env1.enclClass.sym);
2397
2398 // Return the type variable if we have it, and have no
2399 // immediate member, OR the type variable is for a method.
2400 if (tyvar != typeNotFound) {
2401 if (env.baseClause || sym == typeNotFound ||
2402 (tyvar.kind == TYP && tyvar.exists() &&
2403 tyvar.owner.kind == MTH)) {
2404 return tyvar;
2405 }
2406 }
2407
2408 // If the environment is a class def, finish up,
2409 // otherwise, do the entire findMemberType
2410 if (sym == typeNotFound)
2411 sym = findInheritedMemberType(env1, env1.enclClass.sym.type,
2412 name, env1.enclClass.sym);
2413
2414 if (staticOnly && sym.kind == TYP &&
2415 sym.type.hasTag(CLASS) &&
2416 sym.type.getEnclosingType().hasTag(CLASS) &&
2417 env1.enclClass.sym.type.isParameterized() &&
2418 sym.type.getEnclosingType().isParameterized())
2419 return new StaticError(sym);
2420 else if (sym.exists()) return sym;
2421 else bestSoFar = bestOf(bestSoFar, sym);
2422
2423 JCClassDecl encl = env1.baseClause ? (JCClassDecl)env1.tree : env1.enclClass;
2424 if ((encl.sym.flags() & STATIC) != 0)
2425 staticOnly = true;
2426 }
2427
2428 if (!env.tree.hasTag(IMPORT)) {
2429 sym = findGlobalType(env, env.toplevel.namedImportScope, name, namedImportScopeRecovery);
2430 if (sym.exists()) return sym;
2431 else bestSoFar = bestOf(bestSoFar, sym);
2432
2433 sym = findGlobalType(env, env.toplevel.toplevelScope, name, noRecovery);
2434 if (sym.exists()) return sym;
2435 else bestSoFar = bestOf(bestSoFar, sym);
2436
2437 sym = findGlobalType(env, env.toplevel.packge.members(), name, noRecovery);
2438 if (sym.exists()) return sym;
2439 else bestSoFar = bestOf(bestSoFar, sym);
2440
2441 sym = findGlobalType(env, env.toplevel.starImportScope, name, starImportScopeRecovery);
2442 if (sym.exists()) return sym;
2443 else bestSoFar = bestOf(bestSoFar, sym);
2444 }
2445
2446 return bestSoFar;
2447 }
2448
2449 /** Find an unqualified identifier which matches a specified kind set.
2450 * @param pos position on which report warnings, if any;
2451 * null warnings should not be reported
2452 * @param env The current environment.
2453 * @param name The identifier's name.
2454 * @param kind Indicates the possible symbol kinds
2455 * (a subset of VAL, TYP, PCK).
2456 */
2457 Symbol findIdent(DiagnosticPosition pos, Env<AttrContext> env, Name name, KindSelector kind) {
2458 try {
2459 return checkNonExistentType(checkRestrictedType(pos, findIdentInternal(pos, env, name, kind), name));
2460 } catch (ClassFinder.BadClassFile err) {
2461 return new BadClassFileError(err);
2462 } catch (CompletionFailure cf) {
2463 chk.completionError(pos, cf);
2464 return typeNotFound;
2465 }
2466 }
2467
2468 Symbol findIdentInternal(DiagnosticPosition pos, Env<AttrContext> env, Name name, KindSelector kind) {
2469 Symbol bestSoFar = typeNotFound;
2470 Symbol sym;
2471
2472 if (kind.contains(KindSelector.VAL)) {
2473 sym = findVar(pos, env, name);
2474 if (sym.exists()) return sym;
2475 else bestSoFar = bestOf(bestSoFar, sym);
2476 }
2477
2478 if (kind.contains(KindSelector.TYP)) {
2479 sym = findType(env, name);
2480 if (sym.exists()) return sym;
2481 else bestSoFar = bestOf(bestSoFar, sym);
2482 }
2483
2484 if (kind.contains(KindSelector.PCK))
2485 return lookupPackage(env, name);
2486 else return bestSoFar;
2487 }
2488
2489 /** Find an identifier in a package which matches a specified kind set.
2490 * @param pos position on which report warnings, if any;
2491 * null warnings should not be reported
2492 * @param env The current environment.
2493 * @param name The identifier's name.
2494 * @param kind Indicates the possible symbol kinds
2495 * (a nonempty subset of TYP, PCK).
2496 */
2497 Symbol findIdentInPackage(DiagnosticPosition pos,
2498 Env<AttrContext> env, TypeSymbol pck,
2499 Name name, KindSelector kind) {
2500 return checkNonExistentType(checkRestrictedType(pos, findIdentInPackageInternal(env, pck, name, kind), name));
2501 }
2502
2503 Symbol findIdentInPackageInternal(Env<AttrContext> env, TypeSymbol pck,
2504 Name name, KindSelector kind) {
2505 Name fullname = TypeSymbol.formFullName(name, pck);
2506 Symbol bestSoFar = typeNotFound;
2507 if (kind.contains(KindSelector.TYP)) {
2508 RecoveryLoadClass recoveryLoadClass =
2509 allowModules && !kind.contains(KindSelector.PCK) &&
2510 !pck.exists() && !env.info.attributionMode.isSpeculative ?
2511 doRecoveryLoadClass : noRecovery;
2512 Symbol sym = loadClass(env, fullname, recoveryLoadClass);
2513 if (sym.exists()) {
2514 // don't allow programs to use flatnames
2515 if (name == sym.name) return sym;
2516 }
2517 else bestSoFar = bestOf(bestSoFar, sym);
2518 }
2519 if (kind.contains(KindSelector.PCK)) {
2520 return lookupPackage(env, fullname);
2521 }
2522 return bestSoFar;
2523 }
2524
2525 /** Find an identifier among the members of a given type `site'.
2526 * @param pos position on which report warnings, if any;
2527 * null warnings should not be reported
2528 * @param env The current environment.
2529 * @param site The type containing the symbol to be found.
2530 * @param name The identifier's name.
2531 * @param kind Indicates the possible symbol kinds
2532 * (a subset of VAL, TYP).
2533 */
2534 Symbol findIdentInType(DiagnosticPosition pos,
2535 Env<AttrContext> env, Type site,
2536 Name name, KindSelector kind) {
2537 try {
2538 return checkNonExistentType(checkRestrictedType(pos, findIdentInTypeInternal(env, site, name, kind), name));
2539 } catch (ClassFinder.BadClassFile err) {
2540 return new BadClassFileError(err);
2541 } catch (CompletionFailure cf) {
2542 chk.completionError(pos, cf);
2543 return typeNotFound;
2544 }
2545 }
2546
2547 private Symbol checkNonExistentType(Symbol symbol) {
2548 /* Guard against returning a type is not on the class path of the current compilation,
2549 * but *was* on the class path of a separate compilation that produced a class file
2550 * that is on the class path of the current compilation. Such a type will fail completion
2551 * but the completion failure may have been silently swallowed (e.g. missing annotation types)
2552 * with an error stub symbol lingering in the symbol tables.
2553 */
2554 return symbol instanceof ClassSymbol c && c.type.isErroneous() && c.classfile == null ? typeNotFound : symbol;
2555 }
2556
2557 Symbol findIdentInTypeInternal(Env<AttrContext> env, Type site,
2558 Name name, KindSelector kind) {
2559 Symbol bestSoFar = typeNotFound;
2560 Symbol sym;
2561 if (kind.contains(KindSelector.VAL)) {
2562 sym = findField(env, site, name, site.tsym);
2563 if (sym.exists()) return sym;
2564 else bestSoFar = bestOf(bestSoFar, sym);
2565 }
2566
2567 if (kind.contains(KindSelector.TYP)) {
2568 sym = findMemberType(env, site, name, site.tsym);
2569 if (sym.exists()) return sym;
2570 else bestSoFar = bestOf(bestSoFar, sym);
2571 }
2572 return bestSoFar;
2573 }
2574
2575 private Symbol checkRestrictedType(DiagnosticPosition pos, Symbol bestSoFar, Name name) {
2576 if (bestSoFar.kind == TYP || bestSoFar.kind == ABSENT_TYP) {
2577 if (allowLocalVariableTypeInference && name.equals(names.var)) {
2578 bestSoFar = new BadRestrictedTypeError(names.var);
2579 } else if (name.equals(names.yield)) {
2580 if (allowYieldStatement) {
2581 bestSoFar = new BadRestrictedTypeError(names.yield);
2582 } else if (pos != null) {
2583 log.warning(pos, Warnings.IllegalRefToRestrictedType(names.yield));
2584 }
2585 }
2586 }
2587 return bestSoFar;
2588 }
2589
2590 /* ***************************************************************************
2591 * Access checking
2592 * The following methods convert ResolveErrors to ErrorSymbols, issuing
2593 * an error message in the process
2594 ****************************************************************************/
2595
2596 /** If `sym' is a bad symbol: report error and return errSymbol
2597 * else pass through unchanged,
2598 * additional arguments duplicate what has been used in trying to find the
2599 * symbol {@literal (--> flyweight pattern)}. This improves performance since we
2600 * expect misses to happen frequently.
2601 *
2602 * @param sym The symbol that was found, or a ResolveError.
2603 * @param pos The position to use for error reporting.
2604 * @param location The symbol the served as a context for this lookup
2605 * @param site The original type from where the selection took place.
2606 * @param name The symbol's name.
2607 * @param qualified Did we get here through a qualified expression resolution?
2608 * @param argtypes The invocation's value arguments,
2609 * if we looked for a method.
2610 * @param typeargtypes The invocation's type arguments,
2611 * if we looked for a method.
2612 * @param logResolveHelper helper class used to log resolve errors
2613 */
2614 Symbol accessInternal(Symbol sym,
2615 DiagnosticPosition pos,
2616 Symbol location,
2617 Type site,
2618 Name name,
2619 boolean qualified,
2620 List<Type> argtypes,
2621 List<Type> typeargtypes,
2622 LogResolveHelper logResolveHelper) {
2623 if (sym.kind.isResolutionError()) {
2624 ResolveError errSym = (ResolveError)sym.baseSymbol();
2625 sym = errSym.access(name, qualified ? site.tsym : syms.noSymbol);
2626 argtypes = logResolveHelper.getArgumentTypes(errSym, sym, name, argtypes);
2627 if (logResolveHelper.resolveDiagnosticNeeded(site, argtypes, typeargtypes)) {
2628 logResolveError(errSym, pos, location, site, name, argtypes, typeargtypes);
2629 }
2630 }
2631 return sym;
2632 }
2633
2634 /**
2635 * Variant of the generalized access routine, to be used for generating method
2636 * resolution diagnostics
2637 */
2638 Symbol accessMethod(Symbol sym,
2639 DiagnosticPosition pos,
2640 Symbol location,
2641 Type site,
2642 Name name,
2643 boolean qualified,
2644 List<Type> argtypes,
2645 List<Type> typeargtypes) {
2646 return accessInternal(sym, pos, location, site, name, qualified, argtypes, typeargtypes, methodLogResolveHelper);
2647 }
2648
2649 /** Same as original accessMethod(), but without location.
2650 */
2651 Symbol accessMethod(Symbol sym,
2652 DiagnosticPosition pos,
2653 Type site,
2654 Name name,
2655 boolean qualified,
2656 List<Type> argtypes,
2657 List<Type> typeargtypes) {
2658 return accessMethod(sym, pos, site.tsym, site, name, qualified, argtypes, typeargtypes);
2659 }
2660
2661 /**
2662 * Variant of the generalized access routine, to be used for generating variable,
2663 * type resolution diagnostics
2664 */
2665 Symbol accessBase(Symbol sym,
2666 DiagnosticPosition pos,
2667 Symbol location,
2668 Type site,
2669 Name name,
2670 boolean qualified) {
2671 return accessInternal(sym, pos, location, site, name, qualified, List.nil(), null, basicLogResolveHelper);
2672 }
2673
2674 /** Same as original accessBase(), but without location.
2675 */
2676 Symbol accessBase(Symbol sym,
2677 DiagnosticPosition pos,
2678 Type site,
2679 Name name,
2680 boolean qualified) {
2681 return accessBase(sym, pos, site.tsym, site, name, qualified);
2682 }
2683
2684 interface LogResolveHelper {
2685 boolean resolveDiagnosticNeeded(Type site, List<Type> argtypes, List<Type> typeargtypes);
2686 List<Type> getArgumentTypes(ResolveError errSym, Symbol accessedSym, Name name, List<Type> argtypes);
2687 }
2688
2689 LogResolveHelper basicLogResolveHelper = new LogResolveHelper() {
2690 public boolean resolveDiagnosticNeeded(Type site, List<Type> argtypes, List<Type> typeargtypes) {
2691 return !site.isErroneous();
2692 }
2693 public List<Type> getArgumentTypes(ResolveError errSym, Symbol accessedSym, Name name, List<Type> argtypes) {
2694 return argtypes;
2695 }
2696 };
2697
2698 LogResolveHelper silentLogResolveHelper = new LogResolveHelper() {
2699 public boolean resolveDiagnosticNeeded(Type site, List<Type> argtypes, List<Type> typeargtypes) {
2700 return false;
2701 }
2702 public List<Type> getArgumentTypes(ResolveError errSym, Symbol accessedSym, Name name, List<Type> argtypes) {
2703 return argtypes;
2704 }
2705 };
2706
2707 LogResolveHelper methodLogResolveHelper = new LogResolveHelper() {
2708 public boolean resolveDiagnosticNeeded(Type site, List<Type> argtypes, List<Type> typeargtypes) {
2709 return !site.isErroneous() &&
2710 !Type.isErroneous(argtypes) &&
2711 (typeargtypes == null || !Type.isErroneous(typeargtypes));
2712 }
2713 public List<Type> getArgumentTypes(ResolveError errSym, Symbol accessedSym, Name name, List<Type> argtypes) {
2714 return argtypes.map(new ResolveDeferredRecoveryMap(AttrMode.SPECULATIVE, accessedSym, currentResolutionContext.step));
2715 }
2716 };
2717
2718 class ResolveDeferredRecoveryMap extends DeferredAttr.RecoveryDeferredTypeMap {
2719
2720 public ResolveDeferredRecoveryMap(AttrMode mode, Symbol msym, MethodResolutionPhase step) {
2721 deferredAttr.super(mode, msym, step);
2722 }
2723
2724 @Override
2725 protected Type typeOf(DeferredType dt, Type pt) {
2726 Type res = super.typeOf(dt, pt);
2727 if (!res.isErroneous()) {
2728 switch (TreeInfo.skipParens(dt.tree).getTag()) {
2729 case LAMBDA:
2730 case REFERENCE:
2731 return dt;
2732 case CONDEXPR:
2733 return res == Type.recoveryType ?
2734 dt : res;
2735 }
2736 }
2737 return res;
2738 }
2739 }
2740
2741 /** Check that sym is not an abstract method.
2742 */
2743 void checkNonAbstract(DiagnosticPosition pos, Symbol sym) {
2744 if ((sym.flags() & ABSTRACT) != 0 && (sym.flags() & DEFAULT) == 0)
2745 log.error(pos,
2746 Errors.AbstractCantBeAccessedDirectly(kindName(sym),sym, sym.location()));
2747 }
2748
2749 /* ***************************************************************************
2750 * Name resolution
2751 * Naming conventions are as for symbol lookup
2752 * Unlike the find... methods these methods will report access errors
2753 ****************************************************************************/
2754
2755 /** Resolve an unqualified (non-method) identifier.
2756 * @param pos The position to use for error reporting.
2757 * @param env The environment current at the identifier use.
2758 * @param name The identifier's name.
2759 * @param kind The set of admissible symbol kinds for the identifier.
2760 */
2761 Symbol resolveIdent(DiagnosticPosition pos, Env<AttrContext> env,
2762 Name name, KindSelector kind) {
2763 return accessBase(
2764 findIdent(pos, env, name, kind),
2765 pos, env.enclClass.sym.type, name, false);
2766 }
2767
2768 /** Resolve an unqualified method identifier.
2769 * @param pos The position to use for error reporting.
2770 * @param env The environment current at the method invocation.
2771 * @param name The identifier's name.
2772 * @param argtypes The types of the invocation's value arguments.
2773 * @param typeargtypes The types of the invocation's type arguments.
2774 */
2775 Symbol resolveMethod(DiagnosticPosition pos,
2776 Env<AttrContext> env,
2777 Name name,
2778 List<Type> argtypes,
2779 List<Type> typeargtypes) {
2780 return lookupMethod(env, pos, env.enclClass.sym, resolveMethodCheck,
2781 new BasicLookupHelper(name, env.enclClass.sym.type, argtypes, typeargtypes) {
2782 @Override
2783 Symbol lookup(Env<AttrContext> env, MethodResolutionPhase phase) {
2784 return findFun(env, name, argtypes, typeargtypes,
2785 phase.isBoxingRequired(),
2786 phase.isVarargsRequired());
2787 }});
2788 }
2789
2790 /** Resolve a qualified method identifier
2791 * @param pos The position to use for error reporting.
2792 * @param env The environment current at the method invocation.
2793 * @param site The type of the qualifying expression, in which
2794 * identifier is searched.
2795 * @param name The identifier's name.
2796 * @param argtypes The types of the invocation's value arguments.
2797 * @param typeargtypes The types of the invocation's type arguments.
2798 */
2799 Symbol resolveQualifiedMethod(DiagnosticPosition pos, Env<AttrContext> env,
2800 Type site, Name name, List<Type> argtypes,
2801 List<Type> typeargtypes) {
2802 return resolveQualifiedMethod(pos, env, site.tsym, site, name, argtypes, typeargtypes);
2803 }
2804 Symbol resolveQualifiedMethod(DiagnosticPosition pos, Env<AttrContext> env,
2805 Symbol location, Type site, Name name, List<Type> argtypes,
2806 List<Type> typeargtypes) {
2807 return resolveQualifiedMethod(new MethodResolutionContext(), pos, env, location, site, name, argtypes, typeargtypes);
2808 }
2809 private Symbol resolveQualifiedMethod(MethodResolutionContext resolveContext,
2810 DiagnosticPosition pos, Env<AttrContext> env,
2811 Symbol location, Type site, Name name, List<Type> argtypes,
2812 List<Type> typeargtypes) {
2813 return lookupMethod(env, pos, location, resolveContext, new BasicLookupHelper(name, site, argtypes, typeargtypes) {
2814 @Override
2815 Symbol lookup(Env<AttrContext> env, MethodResolutionPhase phase) {
2816 return findMethod(env, site, name, argtypes, typeargtypes,
2817 phase.isBoxingRequired(),
2818 phase.isVarargsRequired());
2819 }
2820 @Override
2821 Symbol access(Env<AttrContext> env, DiagnosticPosition pos, Symbol location, Symbol sym) {
2822 if (sym.kind.isResolutionError()) {
2823 sym = super.access(env, pos, location, sym);
2824 } else {
2825 MethodSymbol msym = (MethodSymbol)sym;
2826 if ((msym.flags() & SIGNATURE_POLYMORPHIC) != 0) {
2827 env.info.pendingResolutionPhase = BASIC;
2828 return findPolymorphicSignatureInstance(env, sym, argtypes);
2829 }
2830 }
2831 return sym;
2832 }
2833 });
2834 }
2835
2836 /** Find or create an implicit method of exactly the given type (after erasure).
2837 * Searches in a side table, not the main scope of the site.
2838 * This emulates the lookup process required by JSR 292 in JVM.
2839 * @param env Attribution environment
2840 * @param spMethod signature polymorphic method - i.e. MH.invokeExact
2841 * @param argtypes The required argument types
2842 */
2843 Symbol findPolymorphicSignatureInstance(Env<AttrContext> env,
2844 final Symbol spMethod,
2845 List<Type> argtypes) {
2846 Type mtype = infer.instantiatePolymorphicSignatureInstance(env,
2847 (MethodSymbol)spMethod, currentResolutionContext, argtypes);
2848 return findPolymorphicSignatureInstance(spMethod, mtype);
2849 }
2850
2851 Symbol findPolymorphicSignatureInstance(final Symbol spMethod,
2852 Type mtype) {
2853 for (Symbol sym : polymorphicSignatureScope.getSymbolsByName(spMethod.name)) {
2854 // Check that there is already a method symbol for the method
2855 // type and owner
2856 if (types.isSameType(mtype, sym.type) &&
2857 spMethod.owner == sym.owner) {
2858 return sym;
2859 }
2860 }
2861
2862 Type spReturnType = spMethod.asType().getReturnType();
2863 if (types.isSameType(spReturnType, syms.objectType)) {
2864 // Polymorphic return, pass through mtype
2865 } else if (!types.isSameType(spReturnType, mtype.getReturnType())) {
2866 // Retain the sig poly method's return type, which differs from that of mtype
2867 // Will result in an incompatible return type error
2868 mtype = new MethodType(mtype.getParameterTypes(),
2869 spReturnType,
2870 mtype.getThrownTypes(),
2871 syms.methodClass);
2872 }
2873
2874 // Create the desired method
2875 // Retain static modifier is to support invocations to
2876 // MethodHandle.linkTo* methods
2877 long flags = ABSTRACT | HYPOTHETICAL |
2878 spMethod.flags() & (Flags.AccessFlags | Flags.STATIC);
2879 Symbol msym = new MethodSymbol(flags, spMethod.name, mtype, spMethod.owner) {
2880 @Override
2881 public Symbol baseSymbol() {
2882 return spMethod;
2883 }
2884 };
2885 if (!mtype.isErroneous()) { // Cache only if kosher.
2886 polymorphicSignatureScope.enter(msym);
2887 }
2888 return msym;
2889 }
2890
2891 /** Resolve a qualified method identifier, throw a fatal error if not
2892 * found.
2893 * @param pos The position to use for error reporting.
2894 * @param env The environment current at the method invocation.
2895 * @param site The type of the qualifying expression, in which
2896 * identifier is searched.
2897 * @param name The identifier's name.
2898 * @param argtypes The types of the invocation's value arguments.
2899 * @param typeargtypes The types of the invocation's type arguments.
2900 */
2901 public MethodSymbol resolveInternalMethod(DiagnosticPosition pos, Env<AttrContext> env,
2902 Type site, Name name,
2903 List<Type> argtypes,
2904 List<Type> typeargtypes) {
2905 MethodResolutionContext resolveContext = new MethodResolutionContext();
2906 resolveContext.internalResolution = true;
2907 Symbol sym = resolveQualifiedMethod(resolveContext, pos, env, site.tsym,
2908 site, name, argtypes, typeargtypes);
2909 if (sym.kind == MTH) return (MethodSymbol)sym;
2910 else throw new FatalError(
2911 diags.fragment(Fragments.FatalErrCantLocateMeth(name)));
2912 }
2913
2914 /** Resolve constructor.
2915 * @param pos The position to use for error reporting.
2916 * @param env The environment current at the constructor invocation.
2917 * @param site The type of class for which a constructor is searched.
2918 * @param argtypes The types of the constructor invocation's value
2919 * arguments.
2920 * @param typeargtypes The types of the constructor invocation's type
2921 * arguments.
2922 */
2923 Symbol resolveConstructor(DiagnosticPosition pos,
2924 Env<AttrContext> env,
2925 Type site,
2926 List<Type> argtypes,
2927 List<Type> typeargtypes) {
2928 return resolveConstructor(new MethodResolutionContext(), pos, env, site, argtypes, typeargtypes);
2929 }
2930
2931 private Symbol resolveConstructor(MethodResolutionContext resolveContext,
2932 final DiagnosticPosition pos,
2933 Env<AttrContext> env,
2934 Type site,
2935 List<Type> argtypes,
2936 List<Type> typeargtypes) {
2937 return lookupMethod(env, pos, site.tsym, resolveContext, new BasicLookupHelper(names.init, site, argtypes, typeargtypes) {
2938 @Override
2939 Symbol lookup(Env<AttrContext> env, MethodResolutionPhase phase) {
2940 return findConstructor(pos, env, site, argtypes, typeargtypes,
2941 phase.isBoxingRequired(),
2942 phase.isVarargsRequired());
2943 }
2944 });
2945 }
2946
2947 /** Resolve a constructor, throw a fatal error if not found.
2948 * @param pos The position to use for error reporting.
2949 * @param env The environment current at the method invocation.
2950 * @param site The type to be constructed.
2951 * @param argtypes The types of the invocation's value arguments.
2952 * @param typeargtypes The types of the invocation's type arguments.
2953 */
2954 public MethodSymbol resolveInternalConstructor(DiagnosticPosition pos, Env<AttrContext> env,
2955 Type site,
2956 List<Type> argtypes,
2957 List<Type> typeargtypes) {
2958 MethodResolutionContext resolveContext = new MethodResolutionContext();
2959 resolveContext.internalResolution = true;
2960 Symbol sym = resolveConstructor(resolveContext, pos, env, site, argtypes, typeargtypes);
2961 if (sym.kind == MTH) return (MethodSymbol)sym;
2962 else throw new FatalError(
2963 diags.fragment(Fragments.FatalErrCantLocateCtor(site)));
2964 }
2965
2966 Symbol findConstructor(DiagnosticPosition pos, Env<AttrContext> env,
2967 Type site, List<Type> argtypes,
2968 List<Type> typeargtypes,
2969 boolean allowBoxing,
2970 boolean useVarargs) {
2971 Symbol sym = findMethod(env, site,
2972 names.init, argtypes,
2973 typeargtypes, allowBoxing,
2974 useVarargs);
2975 chk.checkDeprecated(pos, env.info.scope.owner, sym);
2976 chk.checkPreview(pos, env.info.scope.owner, sym);
2977 return sym;
2978 }
2979
2980 /** Resolve constructor using diamond inference.
2981 * @param pos The position to use for error reporting.
2982 * @param env The environment current at the constructor invocation.
2983 * @param site The type of class for which a constructor is searched.
2984 * The scope of this class has been touched in attribution.
2985 * @param argtypes The types of the constructor invocation's value
2986 * arguments.
2987 * @param typeargtypes The types of the constructor invocation's type
2988 * arguments.
2989 */
2990 Symbol resolveDiamond(DiagnosticPosition pos,
2991 Env<AttrContext> env,
2992 Type site,
2993 List<Type> argtypes,
2994 List<Type> typeargtypes) {
2995 return lookupMethod(env, pos, site.tsym, resolveMethodCheck,
2996 new BasicLookupHelper(names.init, site, argtypes, typeargtypes) {
2997 @Override
2998 Symbol lookup(Env<AttrContext> env, MethodResolutionPhase phase) {
2999 return findDiamond(pos, env, site, argtypes, typeargtypes,
3000 phase.isBoxingRequired(),
3001 phase.isVarargsRequired());
3002 }
3003 @Override
3004 Symbol access(Env<AttrContext> env, DiagnosticPosition pos, Symbol location, Symbol sym) {
3005 if (sym.kind.isResolutionError()) {
3006 if (sym.kind != WRONG_MTH &&
3007 sym.kind != WRONG_MTHS) {
3008 sym = super.access(env, pos, location, sym);
3009 } else {
3010 sym = new DiamondError(sym, currentResolutionContext);
3011 sym = accessMethod(sym, pos, site, names.init, true, argtypes, typeargtypes);
3012 env.info.pendingResolutionPhase = currentResolutionContext.step;
3013 }
3014 }
3015 return sym;
3016 }});
3017 }
3018
3019 /** Find the constructor using diamond inference and do some checks(deprecated and preview).
3020 * @param pos The position to use for error reporting.
3021 * @param env The environment current at the constructor invocation.
3022 * @param site The type of class for which a constructor is searched.
3023 * The scope of this class has been touched in attribution.
3024 * @param argtypes The types of the constructor invocation's value arguments.
3025 * @param typeargtypes The types of the constructor invocation's type arguments.
3026 * @param allowBoxing Allow boxing conversions of arguments.
3027 * @param useVarargs Box trailing arguments into an array for varargs.
3028 */
3029 private Symbol findDiamond(DiagnosticPosition pos,
3030 Env<AttrContext> env,
3031 Type site,
3032 List<Type> argtypes,
3033 List<Type> typeargtypes,
3034 boolean allowBoxing,
3035 boolean useVarargs) {
3036 Symbol sym = findDiamond(env, site, argtypes, typeargtypes, allowBoxing, useVarargs);
3037 chk.checkDeprecated(pos, env.info.scope.owner, sym);
3038 chk.checkPreview(pos, env.info.scope.owner, sym);
3039 return sym;
3040 }
3041
3042 /** This method scans all the constructor symbol in a given class scope -
3043 * assuming that the original scope contains a constructor of the kind:
3044 * {@code Foo(X x, Y y)}, where X,Y are class type-variables declared in Foo,
3045 * a method check is executed against the modified constructor type:
3046 * {@code <X,Y>Foo<X,Y>(X x, Y y)}. This is crucial in order to enable diamond
3047 * inference. The inferred return type of the synthetic constructor IS
3048 * the inferred type for the diamond operator.
3049 */
3050 private Symbol findDiamond(Env<AttrContext> env,
3051 Type site,
3052 List<Type> argtypes,
3053 List<Type> typeargtypes,
3054 boolean allowBoxing,
3055 boolean useVarargs) {
3056 Symbol bestSoFar = methodNotFound;
3057 TypeSymbol tsym = site.tsym.isInterface() ? syms.objectType.tsym : site.tsym;
3058 for (final Symbol sym : tsym.members().getSymbolsByName(names.init)) {
3059 //- System.out.println(" e " + e.sym);
3060 if (sym.kind == MTH &&
3061 (sym.flags_field & SYNTHETIC) == 0) {
3062 List<Type> oldParams = sym.type.hasTag(FORALL) ?
3063 ((ForAll)sym.type).tvars :
3064 List.nil();
3065 Type constrType = new ForAll(site.tsym.type.getTypeArguments().appendList(oldParams),
3066 types.createMethodTypeWithReturn(sym.type.asMethodType(), site));
3067 MethodSymbol newConstr = new MethodSymbol(sym.flags(), names.init, constrType, site.tsym) {
3068 @Override
3069 public Symbol baseSymbol() {
3070 return sym;
3071 }
3072 };
3073 bestSoFar = selectBest(env, site, argtypes, typeargtypes,
3074 newConstr,
3075 bestSoFar,
3076 allowBoxing,
3077 useVarargs);
3078 }
3079 }
3080 return bestSoFar;
3081 }
3082
3083 Symbol getMemberReference(DiagnosticPosition pos,
3084 Env<AttrContext> env,
3085 JCMemberReference referenceTree,
3086 Type site,
3087 Name name) {
3088
3089 site = types.capture(site);
3090
3091 ReferenceLookupHelper lookupHelper = makeReferenceLookupHelper(
3092 referenceTree, site, name, List.nil(), null, VARARITY);
3093
3094 Env<AttrContext> newEnv = env.dup(env.tree, env.info.dup());
3095 Symbol sym = lookupMethod(newEnv, env.tree.pos(), site.tsym,
3096 nilMethodCheck, lookupHelper);
3097
3098 env.info.pendingResolutionPhase = newEnv.info.pendingResolutionPhase;
3099
3100 return sym;
3101 }
3102
3103 ReferenceLookupHelper makeReferenceLookupHelper(JCMemberReference referenceTree,
3104 Type site,
3105 Name name,
3106 List<Type> argtypes,
3107 List<Type> typeargtypes,
3108 MethodResolutionPhase maxPhase) {
3109 if (!name.equals(names.init)) {
3110 //method reference
3111 return new MethodReferenceLookupHelper(referenceTree, name, site, argtypes, typeargtypes, maxPhase);
3112 } else if (site.hasTag(ARRAY)) {
3113 //array constructor reference
3114 return new ArrayConstructorReferenceLookupHelper(referenceTree, site, argtypes, typeargtypes, maxPhase);
3115 } else {
3116 //class constructor reference
3117 return new ConstructorReferenceLookupHelper(referenceTree, site, argtypes, typeargtypes, maxPhase);
3118 }
3119 }
3120
3121 /**
3122 * Resolution of member references is typically done as a single
3123 * overload resolution step, where the argument types A are inferred from
3124 * the target functional descriptor.
3125 *
3126 * If the member reference is a method reference with a type qualifier,
3127 * a two-step lookup process is performed. The first step uses the
3128 * expected argument list A, while the second step discards the first
3129 * type from A (which is treated as a receiver type).
3130 *
3131 * There are two cases in which inference is performed: (i) if the member
3132 * reference is a constructor reference and the qualifier type is raw - in
3133 * which case diamond inference is used to infer a parameterization for the
3134 * type qualifier; (ii) if the member reference is an unbound reference
3135 * where the type qualifier is raw - in that case, during the unbound lookup
3136 * the receiver argument type is used to infer an instantiation for the raw
3137 * qualifier type.
3138 *
3139 * When a multi-step resolution process is exploited, the process of picking
3140 * the resulting symbol is delegated to an helper class {@link com.sun.tools.javac.comp.Resolve.ReferenceChooser}.
3141 *
3142 * This routine returns a pair (T,S), where S is the member reference symbol,
3143 * and T is the type of the class in which S is defined. This is necessary as
3144 * the type T might be dynamically inferred (i.e. if constructor reference
3145 * has a raw qualifier).
3146 */
3147 Pair<Symbol, ReferenceLookupHelper> resolveMemberReference(Env<AttrContext> env,
3148 JCMemberReference referenceTree,
3149 Type site,
3150 Name name,
3151 List<Type> argtypes,
3152 List<Type> typeargtypes,
3153 Type descriptor,
3154 MethodCheck methodCheck,
3155 InferenceContext inferenceContext,
3156 ReferenceChooser referenceChooser) {
3157
3158 //step 1 - bound lookup
3159 ReferenceLookupHelper boundLookupHelper = makeReferenceLookupHelper(
3160 referenceTree, site, name, argtypes, typeargtypes, VARARITY);
3161 Env<AttrContext> boundEnv = env.dup(env.tree, env.info.dup());
3162 MethodResolutionContext boundSearchResolveContext = new MethodResolutionContext();
3163 boundSearchResolveContext.methodCheck = methodCheck;
3164 Symbol boundSym = lookupMethod(boundEnv, env.tree.pos(),
3165 site.tsym, boundSearchResolveContext, boundLookupHelper);
3166 boolean isStaticSelector = TreeInfo.isStaticSelector(referenceTree.expr, names);
3167 ReferenceLookupResult boundRes = new ReferenceLookupResult(boundSym, boundSearchResolveContext, isStaticSelector);
3168 if (dumpMethodReferenceSearchResults) {
3169 dumpMethodReferenceSearchResults(referenceTree, boundSearchResolveContext, boundSym, true);
3170 }
3171
3172 //step 2 - unbound lookup
3173 Symbol unboundSym = methodNotFound;
3174 Env<AttrContext> unboundEnv = env.dup(env.tree, env.info.dup());
3175 ReferenceLookupHelper unboundLookupHelper = boundLookupHelper.unboundLookup(inferenceContext);
3176 ReferenceLookupResult unboundRes = referenceNotFound;
3177 if (unboundLookupHelper != null) {
3178 MethodResolutionContext unboundSearchResolveContext =
3179 new MethodResolutionContext();
3180 unboundSearchResolveContext.methodCheck = methodCheck;
3181 unboundSym = lookupMethod(unboundEnv, env.tree.pos(),
3182 site.tsym, unboundSearchResolveContext, unboundLookupHelper);
3183 unboundRes = new ReferenceLookupResult(unboundSym, unboundSearchResolveContext, isStaticSelector);
3184 if (dumpMethodReferenceSearchResults) {
3185 dumpMethodReferenceSearchResults(referenceTree, unboundSearchResolveContext, unboundSym, false);
3186 }
3187 }
3188
3189 //merge results
3190 Pair<Symbol, ReferenceLookupHelper> res;
3191 ReferenceLookupResult bestRes = referenceChooser.result(boundRes, unboundRes);
3192 res = new Pair<>(bestRes.sym,
3193 bestRes == unboundRes ? unboundLookupHelper : boundLookupHelper);
3194 env.info.pendingResolutionPhase = bestRes == unboundRes ?
3195 unboundEnv.info.pendingResolutionPhase :
3196 boundEnv.info.pendingResolutionPhase;
3197
3198 if (!res.fst.kind.isResolutionError()) {
3199 //handle sigpoly method references
3200 MethodSymbol msym = (MethodSymbol)res.fst;
3201 if ((msym.flags() & SIGNATURE_POLYMORPHIC) != 0) {
3202 env.info.pendingResolutionPhase = BASIC;
3203 res = new Pair<>(findPolymorphicSignatureInstance(msym, descriptor), res.snd);
3204 }
3205 }
3206
3207 return res;
3208 }
3209
3210 private void dumpMethodReferenceSearchResults(JCMemberReference referenceTree,
3211 MethodResolutionContext resolutionContext,
3212 Symbol bestSoFar,
3213 boolean bound) {
3214 ListBuffer<JCDiagnostic> subDiags = new ListBuffer<>();
3215 int pos = 0;
3216 int mostSpecificPos = -1;
3217 for (Candidate c : resolutionContext.candidates) {
3218 if (resolutionContext.step != c.step || !c.isApplicable()) {
3219 continue;
3220 } else {
3221 JCDiagnostic subDiag = null;
3222 if (c.sym.type.hasTag(FORALL)) {
3223 subDiag = diags.fragment(Fragments.PartialInstSig(c.mtype));
3224 }
3225
3226 String key = subDiag == null ?
3227 "applicable.method.found.2" :
3228 "applicable.method.found.3";
3229 subDiags.append(diags.fragment(key, pos,
3230 c.sym.isStatic() ? Fragments.Static : Fragments.NonStatic, c.sym, subDiag));
3231 if (c.sym == bestSoFar)
3232 mostSpecificPos = pos;
3233 pos++;
3234 }
3235 }
3236 JCDiagnostic main = diags.note(
3237 log.currentSource(),
3238 referenceTree,
3239 "method.ref.search.results.multi",
3240 bound ? Fragments.Bound : Fragments.Unbound,
3241 referenceTree.toString(), mostSpecificPos);
3242 JCDiagnostic d = new JCDiagnostic.MultilineDiagnostic(main, subDiags.toList());
3243 log.report(d);
3244 }
3245
3246 /**
3247 * This class is used to represent a method reference lookup result. It keeps track of two
3248 * things: (i) the symbol found during a method reference lookup and (ii) the static kind
3249 * of the lookup (see {@link com.sun.tools.javac.comp.Resolve.ReferenceLookupResult.StaticKind}).
3250 */
3251 static class ReferenceLookupResult {
3252
3253 /**
3254 * Static kind associated with a method reference lookup. Erroneous lookups end up with
3255 * the UNDEFINED kind; successful lookups will end up with either STATIC, NON_STATIC,
3256 * depending on whether all applicable candidates are static or non-static methods,
3257 * respectively. If a successful lookup has both static and non-static applicable methods,
3258 * its kind is set to BOTH.
3259 */
3260 enum StaticKind {
3261 STATIC,
3262 NON_STATIC,
3263 BOTH,
3264 UNDEFINED;
3265
3266 /**
3267 * Retrieve the static kind associated with a given (method) symbol.
3268 */
3269 static StaticKind from(Symbol s) {
3270 return s.isStatic() ?
3271 STATIC : NON_STATIC;
3272 }
3273
3274 /**
3275 * Merge two static kinds together.
3276 */
3277 static StaticKind reduce(StaticKind sk1, StaticKind sk2) {
3278 if (sk1 == UNDEFINED) {
3279 return sk2;
3280 } else if (sk2 == UNDEFINED) {
3281 return sk1;
3282 } else {
3283 return sk1 == sk2 ? sk1 : BOTH;
3284 }
3285 }
3286 }
3287
3288 /** The static kind. */
3289 StaticKind staticKind;
3290
3291 /** The lookup result. */
3292 Symbol sym;
3293
3294 ReferenceLookupResult(Symbol sym, MethodResolutionContext resolutionContext, boolean isStaticSelector) {
3295 this(sym, staticKind(sym, resolutionContext, isStaticSelector));
3296 }
3297
3298 private ReferenceLookupResult(Symbol sym, StaticKind staticKind) {
3299 this.staticKind = staticKind;
3300 this.sym = sym;
3301 }
3302
3303 private static StaticKind staticKind(Symbol sym, MethodResolutionContext resolutionContext, boolean isStaticSelector) {
3304 if (sym.kind == MTH && !isStaticSelector) {
3305 return StaticKind.from(sym);
3306 } else if (sym.kind == MTH || sym.kind == AMBIGUOUS) {
3307 return resolutionContext.candidates.stream()
3308 .filter(c -> c.isApplicable() && c.step == resolutionContext.step)
3309 .map(c -> StaticKind.from(c.sym))
3310 .reduce(StaticKind::reduce)
3311 .orElse(StaticKind.UNDEFINED);
3312 } else {
3313 return StaticKind.UNDEFINED;
3314 }
3315 }
3316
3317 /**
3318 * Does this result corresponds to a successful lookup (i.e. one where a method has been found?)
3319 */
3320 boolean isSuccess() {
3321 return staticKind != StaticKind.UNDEFINED;
3322 }
3323
3324 /**
3325 * Does this result have given static kind?
3326 */
3327 boolean hasKind(StaticKind sk) {
3328 return this.staticKind == sk;
3329 }
3330
3331 /**
3332 * Error recovery helper: can this lookup result be ignored (for the purpose of returning
3333 * some 'better' result) ?
3334 */
3335 boolean canIgnore() {
3336 switch (sym.kind) {
3337 case ABSENT_MTH:
3338 return true;
3339 case WRONG_MTH:
3340 InapplicableSymbolError errSym =
3341 (InapplicableSymbolError)sym.baseSymbol();
3342 return new Template(MethodCheckDiag.ARITY_MISMATCH.regex())
3343 .matches(errSym.errCandidate().snd);
3344 case WRONG_MTHS:
3345 InapplicableSymbolsError errSyms =
3346 (InapplicableSymbolsError)sym.baseSymbol();
3347 return errSyms.filterCandidates(errSyms.mapCandidates()).isEmpty();
3348 default:
3349 return false;
3350 }
3351 }
3352
3353 static ReferenceLookupResult error(Symbol sym) {
3354 return new ReferenceLookupResult(sym, StaticKind.UNDEFINED);
3355 }
3356 }
3357
3358 /**
3359 * This abstract class embodies the logic that converts one (bound lookup) or two (unbound lookup)
3360 * {@code ReferenceLookupResult} objects into a {@code Symbol}, which is then regarded as the
3361 * result of method reference resolution.
3362 */
3363 abstract class ReferenceChooser {
3364 /**
3365 * Generate a result from a pair of lookup result objects. This method delegates to the
3366 * appropriate result generation routine.
3367 */
3368 ReferenceLookupResult result(ReferenceLookupResult boundRes, ReferenceLookupResult unboundRes) {
3369 return unboundRes != referenceNotFound ?
3370 unboundResult(boundRes, unboundRes) :
3371 boundResult(boundRes);
3372 }
3373
3374 /**
3375 * Generate a symbol from a given bound lookup result.
3376 */
3377 abstract ReferenceLookupResult boundResult(ReferenceLookupResult boundRes);
3378
3379 /**
3380 * Generate a symbol from a pair of bound/unbound lookup results.
3381 */
3382 abstract ReferenceLookupResult unboundResult(ReferenceLookupResult boundRes, ReferenceLookupResult unboundRes);
3383 }
3384
3385 /**
3386 * This chooser implements the selection strategy used during a full lookup; this logic
3387 * is described in JLS SE 8 (15.3.2).
3388 */
3389 ReferenceChooser basicReferenceChooser = new ReferenceChooser() {
3390
3391 @Override
3392 ReferenceLookupResult boundResult(ReferenceLookupResult boundRes) {
3393 return !boundRes.isSuccess() || boundRes.hasKind(StaticKind.NON_STATIC) ?
3394 boundRes : //the search produces a non-static method
3395 ReferenceLookupResult.error(new BadMethodReferenceError(boundRes.sym, false));
3396 }
3397
3398 @Override
3399 ReferenceLookupResult unboundResult(ReferenceLookupResult boundRes, ReferenceLookupResult unboundRes) {
3400 if (boundRes.isSuccess() && boundRes.sym.isStatic() &&
3401 (!unboundRes.isSuccess() || unboundRes.hasKind(StaticKind.STATIC))) {
3402 //the first search produces a static method and no non-static method is applicable
3403 //during the second search
3404 return boundRes;
3405 } else if (unboundRes.isSuccess() && !unboundRes.sym.isStatic() &&
3406 (!boundRes.isSuccess() || boundRes.hasKind(StaticKind.NON_STATIC))) {
3407 //the second search produces a non-static method and no static method is applicable
3408 //during the first search
3409 return unboundRes;
3410 } else if (boundRes.isSuccess() && unboundRes.isSuccess()) {
3411 //both searches produce some result; ambiguity (error recovery)
3412 return ReferenceLookupResult.error(ambiguityError(boundRes.sym, unboundRes.sym));
3413 } else if (boundRes.isSuccess() || unboundRes.isSuccess()) {
3414 //Both searches failed to produce a result with correct staticness (i.e. first search
3415 //produces an non-static method). Alternatively, a given search produced a result
3416 //with the right staticness, but the other search has applicable methods with wrong
3417 //staticness (error recovery)
3418 return ReferenceLookupResult.error(new BadMethodReferenceError(boundRes.isSuccess() ?
3419 boundRes.sym : unboundRes.sym, true));
3420 } else {
3421 //both searches fail to produce a result - pick 'better' error using heuristics (error recovery)
3422 return (boundRes.canIgnore() && !unboundRes.canIgnore()) ?
3423 unboundRes : boundRes;
3424 }
3425 }
3426 };
3427
3428 /**
3429 * This chooser implements the selection strategy used during an arity-based lookup; this logic
3430 * is described in JLS SE 8 (15.12.2.1).
3431 */
3432 ReferenceChooser structuralReferenceChooser = new ReferenceChooser() {
3433
3434 @Override
3435 ReferenceLookupResult boundResult(ReferenceLookupResult boundRes) {
3436 return (!boundRes.isSuccess() || !boundRes.hasKind(StaticKind.STATIC)) ?
3437 boundRes : //the search has at least one applicable non-static method
3438 ReferenceLookupResult.error(new BadMethodReferenceError(boundRes.sym, false));
3439 }
3440
3441 @Override
3442 ReferenceLookupResult unboundResult(ReferenceLookupResult boundRes, ReferenceLookupResult unboundRes) {
3443 if (boundRes.isSuccess() && !boundRes.hasKind(StaticKind.NON_STATIC)) {
3444 //the first search has at least one applicable static method
3445 return boundRes;
3446 } else if (unboundRes.isSuccess() && !unboundRes.hasKind(StaticKind.STATIC)) {
3447 //the second search has at least one applicable non-static method
3448 return unboundRes;
3449 } else if (boundRes.isSuccess() || unboundRes.isSuccess()) {
3450 //either the first search produces a non-static method, or second search produces
3451 //a non-static method (error recovery)
3452 return ReferenceLookupResult.error(new BadMethodReferenceError(boundRes.isSuccess() ?
3453 boundRes.sym : unboundRes.sym, true));
3454 } else {
3455 //both searches fail to produce a result - pick 'better' error using heuristics (error recovery)
3456 return (boundRes.canIgnore() && !unboundRes.canIgnore()) ?
3457 unboundRes : boundRes;
3458 }
3459 }
3460 };
3461
3462 /**
3463 * Helper for defining custom method-like lookup logic; a lookup helper
3464 * provides hooks for (i) the actual lookup logic and (ii) accessing the
3465 * lookup result (this step might result in compiler diagnostics to be generated)
3466 */
3467 abstract class LookupHelper {
3468
3469 /** name of the symbol to lookup */
3470 Name name;
3471
3472 /** location in which the lookup takes place */
3473 Type site;
3474
3475 /** actual types used during the lookup */
3476 List<Type> argtypes;
3477
3478 /** type arguments used during the lookup */
3479 List<Type> typeargtypes;
3480
3481 /** Max overload resolution phase handled by this helper */
3482 MethodResolutionPhase maxPhase;
3483
3484 LookupHelper(Name name, Type site, List<Type> argtypes, List<Type> typeargtypes, MethodResolutionPhase maxPhase) {
3485 this.name = name;
3486 this.site = site;
3487 this.argtypes = argtypes;
3488 this.typeargtypes = typeargtypes;
3489 this.maxPhase = maxPhase;
3490 }
3491
3492 /**
3493 * Should lookup stop at given phase with given result
3494 */
3495 final boolean shouldStop(Symbol sym, MethodResolutionPhase phase) {
3496 return phase.ordinal() > maxPhase.ordinal() ||
3497 !sym.kind.isResolutionError() || sym.kind == AMBIGUOUS || sym.kind == STATICERR;
3498 }
3499
3500 /**
3501 * Search for a symbol under a given overload resolution phase - this method
3502 * is usually called several times, once per each overload resolution phase
3503 */
3504 abstract Symbol lookup(Env<AttrContext> env, MethodResolutionPhase phase);
3505
3506 /**
3507 * Dump overload resolution info
3508 */
3509 void debug(DiagnosticPosition pos, Symbol sym) {
3510 //do nothing
3511 }
3512
3513 /**
3514 * Validate the result of the lookup
3515 */
3516 abstract Symbol access(Env<AttrContext> env, DiagnosticPosition pos, Symbol location, Symbol sym);
3517 }
3518
3519 abstract class BasicLookupHelper extends LookupHelper {
3520
3521 BasicLookupHelper(Name name, Type site, List<Type> argtypes, List<Type> typeargtypes) {
3522 this(name, site, argtypes, typeargtypes, MethodResolutionPhase.VARARITY);
3523 }
3524
3525 BasicLookupHelper(Name name, Type site, List<Type> argtypes, List<Type> typeargtypes, MethodResolutionPhase maxPhase) {
3526 super(name, site, argtypes, typeargtypes, maxPhase);
3527 }
3528
3529 @Override
3530 Symbol access(Env<AttrContext> env, DiagnosticPosition pos, Symbol location, Symbol sym) {
3531 if (sym.kind.isResolutionError()) {
3532 //if nothing is found return the 'first' error
3533 sym = accessMethod(sym, pos, location, site, name, true, argtypes, typeargtypes);
3534 }
3535 return sym;
3536 }
3537
3538 @Override
3539 void debug(DiagnosticPosition pos, Symbol sym) {
3540 reportVerboseResolutionDiagnostic(pos, name, site, argtypes, typeargtypes, sym);
3541 }
3542 }
3543
3544 /**
3545 * Helper class for member reference lookup. A reference lookup helper
3546 * defines the basic logic for member reference lookup; a method gives
3547 * access to an 'unbound' helper used to perform an unbound member
3548 * reference lookup.
3549 */
3550 abstract class ReferenceLookupHelper extends LookupHelper {
3551
3552 /** The member reference tree */
3553 JCMemberReference referenceTree;
3554
3555 ReferenceLookupHelper(JCMemberReference referenceTree, Name name, Type site,
3556 List<Type> argtypes, List<Type> typeargtypes, MethodResolutionPhase maxPhase) {
3557 super(name, site, argtypes, typeargtypes, maxPhase);
3558 this.referenceTree = referenceTree;
3559 }
3560
3561 /**
3562 * Returns an unbound version of this lookup helper. By default, this
3563 * method returns an dummy lookup helper.
3564 */
3565 ReferenceLookupHelper unboundLookup(InferenceContext inferenceContext) {
3566 return null;
3567 }
3568
3569 /**
3570 * Get the kind of the member reference
3571 */
3572 abstract JCMemberReference.ReferenceKind referenceKind(Symbol sym);
3573
3574 Symbol access(Env<AttrContext> env, DiagnosticPosition pos, Symbol location, Symbol sym) {
3575 //skip error reporting
3576 return sym;
3577 }
3578 }
3579
3580 /**
3581 * Helper class for method reference lookup. The lookup logic is based
3582 * upon Resolve.findMethod; in certain cases, this helper class has a
3583 * corresponding unbound helper class (see UnboundMethodReferenceLookupHelper).
3584 * In such cases, non-static lookup results are thrown away.
3585 */
3586 class MethodReferenceLookupHelper extends ReferenceLookupHelper {
3587
3588 /** The original method reference lookup site. */
3589 Type originalSite;
3590
3591 MethodReferenceLookupHelper(JCMemberReference referenceTree, Name name, Type site,
3592 List<Type> argtypes, List<Type> typeargtypes, MethodResolutionPhase maxPhase) {
3593 super(referenceTree, name, types.skipTypeVars(site, true), argtypes, typeargtypes, maxPhase);
3594 this.originalSite = site;
3595 }
3596
3597 @Override
3598 final Symbol lookup(Env<AttrContext> env, MethodResolutionPhase phase) {
3599 return findMethod(env, site, name, argtypes, typeargtypes,
3600 phase.isBoxingRequired(), phase.isVarargsRequired());
3601 }
3602
3603 @Override
3604 ReferenceLookupHelper unboundLookup(InferenceContext inferenceContext) {
3605 if (TreeInfo.isStaticSelector(referenceTree.expr, names)) {
3606 if (argtypes.nonEmpty() &&
3607 (argtypes.head.hasTag(NONE) ||
3608 types.isSubtypeUnchecked(inferenceContext.asUndetVar(argtypes.head), originalSite))) {
3609 return new UnboundMethodReferenceLookupHelper(referenceTree, name,
3610 originalSite, argtypes, typeargtypes, maxPhase);
3611 } else {
3612 return new ReferenceLookupHelper(referenceTree, name, site, argtypes, typeargtypes, maxPhase) {
3613 @Override
3614 ReferenceLookupHelper unboundLookup(InferenceContext inferenceContext) {
3615 return this;
3616 }
3617
3618 @Override
3619 Symbol lookup(Env<AttrContext> env, MethodResolutionPhase phase) {
3620 return methodNotFound;
3621 }
3622
3623 @Override
3624 ReferenceKind referenceKind(Symbol sym) {
3625 Assert.error();
3626 return null;
3627 }
3628 };
3629 }
3630 } else {
3631 return super.unboundLookup(inferenceContext);
3632 }
3633 }
3634
3635 @Override
3636 ReferenceKind referenceKind(Symbol sym) {
3637 if (sym.isStatic()) {
3638 return ReferenceKind.STATIC;
3639 } else {
3640 Name selName = TreeInfo.name(referenceTree.getQualifierExpression());
3641 return selName != null && selName == names._super ?
3642 ReferenceKind.SUPER :
3643 ReferenceKind.BOUND;
3644 }
3645 }
3646
3647 @Override
3648 Symbol access(Env<AttrContext> env, DiagnosticPosition pos, Symbol location, Symbol sym) {
3649 if (originalSite.hasTag(TYPEVAR) && sym.kind == MTH) {
3650 sym = (sym.flags() & Flags.PRIVATE) != 0 ?
3651 new AccessError(env, site, sym) :
3652 sym;
3653 return accessBase(sym, pos, location, originalSite, name, true);
3654 } else {
3655 return super.access(env, pos, location, sym);
3656 }
3657 }
3658 }
3659
3660 /**
3661 * Helper class for unbound method reference lookup. Essentially the same
3662 * as the basic method reference lookup helper; main difference is that static
3663 * lookup results are thrown away. If qualifier type is raw, an attempt to
3664 * infer a parameterized type is made using the first actual argument (that
3665 * would otherwise be ignored during the lookup).
3666 */
3667 class UnboundMethodReferenceLookupHelper extends MethodReferenceLookupHelper {
3668
3669 UnboundMethodReferenceLookupHelper(JCMemberReference referenceTree, Name name, Type site,
3670 List<Type> argtypes, List<Type> typeargtypes, MethodResolutionPhase maxPhase) {
3671 super(referenceTree, name, site, argtypes.tail, typeargtypes, maxPhase);
3672 if (site.isRaw() && !argtypes.head.hasTag(NONE)) {
3673 Type asSuperSite = types.asSuper(argtypes.head, site.tsym);
3674 this.site = types.skipTypeVars(asSuperSite, true);
3675 }
3676 }
3677
3678 @Override
3679 ReferenceLookupHelper unboundLookup(InferenceContext inferenceContext) {
3680 return this;
3681 }
3682
3683 @Override
3684 ReferenceKind referenceKind(Symbol sym) {
3685 return ReferenceKind.UNBOUND;
3686 }
3687 }
3688
3689 /**
3690 * Helper class for array constructor lookup; an array constructor lookup
3691 * is simulated by looking up a method that returns the array type specified
3692 * as qualifier, and that accepts a single int parameter (size of the array).
3693 */
3694 class ArrayConstructorReferenceLookupHelper extends ReferenceLookupHelper {
3695
3696 ArrayConstructorReferenceLookupHelper(JCMemberReference referenceTree, Type site, List<Type> argtypes,
3697 List<Type> typeargtypes, MethodResolutionPhase maxPhase) {
3698 super(referenceTree, names.init, site, argtypes, typeargtypes, maxPhase);
3699 }
3700
3701 @Override
3702 protected Symbol lookup(Env<AttrContext> env, MethodResolutionPhase phase) {
3703 WriteableScope sc = WriteableScope.create(syms.arrayClass);
3704 MethodSymbol arrayConstr = new MethodSymbol(PUBLIC, name, null, site.tsym);
3705 arrayConstr.type = new MethodType(List.of(syms.intType), site, List.nil(), syms.methodClass);
3706 sc.enter(arrayConstr);
3707 return findMethodInScope(env, site, name, argtypes, typeargtypes, sc, methodNotFound, phase.isBoxingRequired(), phase.isVarargsRequired(), false);
3708 }
3709
3710 @Override
3711 ReferenceKind referenceKind(Symbol sym) {
3712 return ReferenceKind.ARRAY_CTOR;
3713 }
3714 }
3715
3716 /**
3717 * Helper class for constructor reference lookup. The lookup logic is based
3718 * upon either Resolve.findMethod or Resolve.findDiamond - depending on
3719 * whether the constructor reference needs diamond inference (this is the case
3720 * if the qualifier type is raw). A special erroneous symbol is returned
3721 * if the lookup returns the constructor of an inner class and there's no
3722 * enclosing instance in scope.
3723 */
3724 class ConstructorReferenceLookupHelper extends ReferenceLookupHelper {
3725
3726 boolean needsInference;
3727
3728 ConstructorReferenceLookupHelper(JCMemberReference referenceTree, Type site, List<Type> argtypes,
3729 List<Type> typeargtypes, MethodResolutionPhase maxPhase) {
3730 super(referenceTree, names.init, site, argtypes, typeargtypes, maxPhase);
3731 if (site.isRaw()) {
3732 this.site = new ClassType(site.getEnclosingType(),
3733 !(site.tsym.isInner() && site.getEnclosingType().isRaw()) ?
3734 site.tsym.type.getTypeArguments() : List.nil(), site.tsym, site.getMetadata());
3735 needsInference = true;
3736 }
3737 }
3738
3739 @Override
3740 protected Symbol lookup(Env<AttrContext> env, MethodResolutionPhase phase) {
3741 Symbol sym = needsInference ?
3742 findDiamond(env, site, argtypes, typeargtypes, phase.isBoxingRequired(), phase.isVarargsRequired()) :
3743 findMethod(env, site, name, argtypes, typeargtypes,
3744 phase.isBoxingRequired(), phase.isVarargsRequired());
3745 return enclosingInstanceMissing(env, site) ? new BadConstructorReferenceError(sym) : sym;
3746 }
3747
3748 @Override
3749 ReferenceKind referenceKind(Symbol sym) {
3750 return site.getEnclosingType().hasTag(NONE) ?
3751 ReferenceKind.TOPLEVEL : ReferenceKind.IMPLICIT_INNER;
3752 }
3753 }
3754
3755 /**
3756 * Main overload resolution routine. On each overload resolution step, a
3757 * lookup helper class is used to perform the method/constructor lookup;
3758 * at the end of the lookup, the helper is used to validate the results
3759 * (this last step might trigger overload resolution diagnostics).
3760 */
3761 Symbol lookupMethod(Env<AttrContext> env, DiagnosticPosition pos, Symbol location, MethodCheck methodCheck, LookupHelper lookupHelper) {
3762 MethodResolutionContext resolveContext = new MethodResolutionContext();
3763 resolveContext.methodCheck = methodCheck;
3764 return lookupMethod(env, pos, location, resolveContext, lookupHelper);
3765 }
3766
3767 Symbol lookupMethod(Env<AttrContext> env, DiagnosticPosition pos, Symbol location,
3768 MethodResolutionContext resolveContext, LookupHelper lookupHelper) {
3769 MethodResolutionContext prevResolutionContext = currentResolutionContext;
3770 try {
3771 Symbol bestSoFar = methodNotFound;
3772 currentResolutionContext = resolveContext;
3773 for (MethodResolutionPhase phase : methodResolutionSteps) {
3774 if (lookupHelper.shouldStop(bestSoFar, phase))
3775 break;
3776 MethodResolutionPhase prevPhase = currentResolutionContext.step;
3777 Symbol prevBest = bestSoFar;
3778 currentResolutionContext.step = phase;
3779 Symbol sym = lookupHelper.lookup(env, phase);
3780 lookupHelper.debug(pos, sym);
3781 bestSoFar = phase.mergeResults(bestSoFar, sym);
3782 env.info.pendingResolutionPhase = (prevBest == bestSoFar) ? prevPhase : phase;
3783 }
3784 return lookupHelper.access(env, pos, location, bestSoFar);
3785 } finally {
3786 currentResolutionContext = prevResolutionContext;
3787 }
3788 }
3789
3790 /**
3791 * Resolve `c.name' where name == this or name == super.
3792 * @param pos The position to use for error reporting.
3793 * @param env The environment current at the expression.
3794 * @param c The qualifier.
3795 * @param name The identifier's name.
3796 */
3797 Symbol resolveSelf(DiagnosticPosition pos,
3798 Env<AttrContext> env,
3799 TypeSymbol c,
3800 Name name) {
3801 Assert.check(name == names._this || name == names._super);
3802 Env<AttrContext> env1 = env;
3803 boolean staticOnly = false;
3804 while (env1.outer != null) {
3805 if (isStatic(env1)) staticOnly = true;
3806 if (env1.enclClass.sym == c) {
3807 Symbol sym = env1.info.scope.findFirst(name);
3808 if (sym != null) {
3809 if (staticOnly)
3810 sym = new StaticError(sym);
3811 else if (env1.info.ctorPrologue && !isAllowedEarlyReference(pos, env1, (VarSymbol)sym))
3812 sym = new RefBeforeCtorCalledError(sym);
3813 return accessBase(sym, pos, env.enclClass.sym.type,
3814 name, true);
3815 }
3816 }
3817 if ((env1.enclClass.sym.flags() & STATIC) != 0) staticOnly = true;
3818 env1 = env1.outer;
3819 }
3820 if (c.isInterface() &&
3821 name == names._super && !isStatic(env) &&
3822 types.isDirectSuperInterface(c, env.enclClass.sym)) {
3823 //this might be a default super call if one of the superinterfaces is 'c'
3824 for (Type t : pruneInterfaces(env.enclClass.type)) {
3825 if (t.tsym == c) {
3826 if (env.info.ctorPrologue)
3827 log.error(pos, Errors.CantRefBeforeCtorCalled(name));
3828 env.info.defaultSuperCallSite = t;
3829 return new VarSymbol(0, names._super,
3830 types.asSuper(env.enclClass.type, c), env.enclClass.sym);
3831 }
3832 }
3833 //find a direct supertype that is a subtype of 'c'
3834 for (Type i : types.directSupertypes(env.enclClass.type)) {
3835 if (i.tsym.isSubClass(c, types) && i.tsym != c) {
3836 log.error(pos,
3837 Errors.IllegalDefaultSuperCall(c,
3838 Fragments.RedundantSupertype(c, i)));
3839 return syms.errSymbol;
3840 }
3841 }
3842 Assert.error();
3843 }
3844 log.error(pos, Errors.NotEnclClass(c));
3845 return syms.errSymbol;
3846 }
3847 //where
3848 private List<Type> pruneInterfaces(Type t) {
3849 ListBuffer<Type> result = new ListBuffer<>();
3850 for (Type t1 : types.interfaces(t)) {
3851 boolean shouldAdd = true;
3852 for (Type t2 : types.directSupertypes(t)) {
3853 if (t1 != t2 && !t2.hasTag(ERROR) && types.isSubtypeNoCapture(t2, t1)) {
3854 shouldAdd = false;
3855 }
3856 }
3857 if (shouldAdd) {
3858 result.append(t1);
3859 }
3860 }
3861 return result.toList();
3862 }
3863
3864 /**
3865 * Determine if an early instance field reference may appear in a constructor prologue.
3866 *
3867 * <p>
3868 * This is only allowed when:
3869 * - The field is being assigned a value (i.e., written but not read)
3870 * - The field is not inherited from a superclass
3871 * - The assignment is not within a lambda, because that would require
3872 * capturing 'this' which is not allowed prior to super().
3873 *
3874 * <p>
3875 * Note, this method doesn't catch all such scenarios, because this method
3876 * is invoked for symbol "x" only for "x = 42" but not for "this.x = 42".
3877 * We also don't verify that the field has no initializer, which is required.
3878 * To catch those cases, we rely on similar logic in Attr.checkAssignable().
3879 */
3880 private boolean isAllowedEarlyReference(DiagnosticPosition pos, Env<AttrContext> env, VarSymbol v) {
3881
3882 // Check assumptions
3883 Assert.check(env.info.ctorPrologue);
3884 Assert.check((v.flags_field & STATIC) == 0);
3885
3886 // The symbol must appear in the LHS of an assignment statement
3887 if (!(env.tree instanceof JCAssign assign))
3888 return false;
3889
3890 // The assignment statement must not be within a lambda
3891 if (env.info.isLambda)
3892 return false;
3893
3894 // Get the symbol's qualifier, if any
3895 JCExpression lhs = TreeInfo.skipParens(assign.lhs);
3896 JCExpression base;
3897 switch (lhs.getTag()) {
3898 case IDENT:
3899 base = null;
3900 break;
3901 case SELECT:
3902 JCFieldAccess select = (JCFieldAccess)lhs;
3903 base = select.selected;
3904 if (!TreeInfo.isExplicitThisReference(types, (ClassType)env.enclClass.type, base))
3905 return false;
3906 break;
3907 default:
3908 return false;
3909 }
3910
3911 // If an early reference, the field must not be declared in a superclass
3912 if (isEarlyReference(env, base, v) && v.owner != env.enclClass.sym)
3913 return false;
3914
3915 // The flexible constructors feature must be enabled
3916 preview.checkSourceLevel(pos, Feature.FLEXIBLE_CONSTRUCTORS);
3917
3918 // OK
3919 return true;
3920 }
3921
3922 /**
3923 * Determine if the variable appearance constitutes an early reference to the current class.
3924 *
3925 * <p>
3926 * This means the variable is an instance field of the current class and it appears
3927 * in an early initialization context of it (i.e., one of its constructor prologues).
3928 *
3929 * <p>
3930 * Such a reference is only allowed for assignments to non-initialized fields that are
3931 * not inherited from a superclass, though that is not enforced by this method.
3932 *
3933 * @param env The current environment
3934 * @param base Variable qualifier, if any, otherwise null
3935 * @param v The variable
3936 */
3937 public boolean isEarlyReference(Env<AttrContext> env, JCTree base, VarSymbol v) {
3938 return env.info.ctorPrologue &&
3939 (v.flags() & STATIC) == 0 &&
3940 v.owner.kind == TYP &&
3941 types.isSubtype(env.enclClass.type, v.owner.type) &&
3942 (base == null || TreeInfo.isExplicitThisReference(types, (ClassType)env.enclClass.type, base));
3943 }
3944
3945 /**
3946 * Resolve `c.this' for an enclosing class c that contains the
3947 * named member.
3948 * @param pos The position to use for error reporting.
3949 * @param env The environment current at the expression.
3950 * @param member The member that must be contained in the result.
3951 */
3952 Symbol resolveSelfContaining(DiagnosticPosition pos,
3953 Env<AttrContext> env,
3954 Symbol member,
3955 boolean isSuperCall) {
3956 Symbol sym = resolveSelfContainingInternal(env, member, isSuperCall);
3957 if (sym == null) {
3958 log.error(pos, Errors.EnclClassRequired(member));
3959 return syms.errSymbol;
3960 } else {
3961 return accessBase(sym, pos, env.enclClass.sym.type, sym.name, true);
3962 }
3963 }
3964
3965 boolean enclosingInstanceMissing(Env<AttrContext> env, Type type) {
3966 if (type.hasTag(CLASS) && type.getEnclosingType().hasTag(CLASS)) {
3967 Symbol encl = resolveSelfContainingInternal(env, type.tsym, false);
3968 return encl == null || encl.kind.isResolutionError();
3969 }
3970 return false;
3971 }
3972
3973 private Symbol resolveSelfContainingInternal(Env<AttrContext> env,
3974 Symbol member,
3975 boolean isSuperCall) {
3976 Name name = names._this;
3977 Env<AttrContext> env1 = isSuperCall ? env.outer : env;
3978 boolean staticOnly = false;
3979 if (env1 != null) {
3980 while (env1 != null && env1.outer != null) {
3981 if (isStatic(env1)) staticOnly = true;
3982 if (env1.enclClass.sym.isSubClass(member.owner.enclClass(), types)) {
3983 Symbol sym = env1.info.scope.findFirst(name);
3984 if (sym != null) {
3985 if (staticOnly) sym = new StaticError(sym);
3986 return sym;
3987 }
3988 }
3989 if ((env1.enclClass.sym.flags() & STATIC) != 0)
3990 staticOnly = true;
3991 env1 = env1.outer;
3992 }
3993 }
3994 return null;
3995 }
3996
3997 /**
3998 * Resolve an appropriate implicit this instance for t's container.
3999 * JLS 8.8.5.1 and 15.9.2
4000 */
4001 Type resolveImplicitThis(DiagnosticPosition pos, Env<AttrContext> env, Type t) {
4002 return resolveImplicitThis(pos, env, t, false);
4003 }
4004
4005 Type resolveImplicitThis(DiagnosticPosition pos, Env<AttrContext> env, Type t, boolean isSuperCall) {
4006 Type thisType = (t.tsym.owner.kind.matches(KindSelector.VAL_MTH)
4007 ? resolveSelf(pos, env, t.getEnclosingType().tsym, names._this)
4008 : resolveSelfContaining(pos, env, t.tsym, isSuperCall)).type;
4009 if (env.info.ctorPrologue && thisType.tsym == env.enclClass.sym) {
4010 log.error(pos, Errors.CantRefBeforeCtorCalled(names._this));
4011 }
4012 return thisType;
4013 }
4014
4015 /* ***************************************************************************
4016 * ResolveError classes, indicating error situations when accessing symbols
4017 ****************************************************************************/
4018
4019 //used by TransTypes when checking target type of synthetic cast
4020 public void logAccessErrorInternal(Env<AttrContext> env, JCTree tree, Type type) {
4021 AccessError error = new AccessError(env, env.enclClass.type, type.tsym);
4022 logResolveError(error, tree.pos(), env.enclClass.sym, env.enclClass.type, null, null, null);
4023 }
4024 //where
4025 private void logResolveError(ResolveError error,
4026 DiagnosticPosition pos,
4027 Symbol location,
4028 Type site,
4029 Name name,
4030 List<Type> argtypes,
4031 List<Type> typeargtypes) {
4032 JCDiagnostic d = error.getDiagnostic(JCDiagnostic.DiagnosticType.ERROR,
4033 pos, location, site, name, argtypes, typeargtypes);
4034 if (d != null) {
4035 d.setFlag(DiagnosticFlag.RESOLVE_ERROR);
4036 log.report(d);
4037 }
4038 }
4039
4040 private final LocalizedString noArgs = new LocalizedString("compiler.misc.no.args");
4041
4042 public Object methodArguments(List<Type> argtypes) {
4043 if (argtypes == null || argtypes.isEmpty()) {
4044 return noArgs;
4045 } else {
4046 ListBuffer<Object> diagArgs = new ListBuffer<>();
4047 for (Type t : argtypes) {
4048 if (t.hasTag(DEFERRED)) {
4049 diagArgs.append(((DeferredAttr.DeferredType)t).tree);
4050 } else {
4051 diagArgs.append(t);
4052 }
4053 }
4054 return diagArgs;
4055 }
4056 }
4057
4058 /** check if a type is a subtype of Serializable, if that is available.*/
4059 boolean isSerializable(Type t) {
4060 try {
4061 syms.serializableType.complete();
4062 }
4063 catch (CompletionFailure e) {
4064 return false;
4065 }
4066 return types.isSubtype(t, syms.serializableType);
4067 }
4068
4069 /**
4070 * Root class for resolution errors. Subclass of ResolveError
4071 * represent a different kinds of resolution error - as such they must
4072 * specify how they map into concrete compiler diagnostics.
4073 */
4074 abstract class ResolveError extends Symbol {
4075
4076 /** The name of the kind of error, for debugging only. */
4077 final String debugName;
4078
4079 ResolveError(Kind kind, String debugName) {
4080 super(kind, 0, null, null, null);
4081 this.debugName = debugName;
4082 }
4083
4084 @Override @DefinedBy(Api.LANGUAGE_MODEL)
4085 public <R, P> R accept(ElementVisitor<R, P> v, P p) {
4086 throw new AssertionError();
4087 }
4088
4089 @Override
4090 public String toString() {
4091 return debugName;
4092 }
4093
4094 @Override
4095 public boolean exists() {
4096 return false;
4097 }
4098
4099 @Override
4100 public boolean isStatic() {
4101 return false;
4102 }
4103
4104 /**
4105 * Create an external representation for this erroneous symbol to be
4106 * used during attribution - by default this returns the symbol of a
4107 * brand new error type which stores the original type found
4108 * during resolution.
4109 *
4110 * @param name the name used during resolution
4111 * @param location the location from which the symbol is accessed
4112 */
4113 protected Symbol access(Name name, TypeSymbol location) {
4114 return types.createErrorType(name, location, syms.errSymbol.type).tsym;
4115 }
4116
4117 /**
4118 * Create a diagnostic representing this resolution error.
4119 *
4120 * @param dkind The kind of the diagnostic to be created (e.g error).
4121 * @param pos The position to be used for error reporting.
4122 * @param site The original type from where the selection took place.
4123 * @param name The name of the symbol to be resolved.
4124 * @param argtypes The invocation's value arguments,
4125 * if we looked for a method.
4126 * @param typeargtypes The invocation's type arguments,
4127 * if we looked for a method.
4128 */
4129 abstract JCDiagnostic getDiagnostic(JCDiagnostic.DiagnosticType dkind,
4130 DiagnosticPosition pos,
4131 Symbol location,
4132 Type site,
4133 Name name,
4134 List<Type> argtypes,
4135 List<Type> typeargtypes);
4136 }
4137
4138 /**
4139 * This class is the root class of all resolution errors caused by
4140 * an invalid symbol being found during resolution.
4141 */
4142 abstract class InvalidSymbolError extends ResolveError {
4143
4144 /** The invalid symbol found during resolution */
4145 Symbol sym;
4146
4147 InvalidSymbolError(Kind kind, Symbol sym, String debugName) {
4148 super(kind, debugName);
4149 this.sym = sym;
4150 }
4151
4152 @Override
4153 public boolean exists() {
4154 return true;
4155 }
4156
4157 @Override
4158 public String toString() {
4159 return super.toString() + " wrongSym=" + sym;
4160 }
4161
4162 @Override
4163 public Symbol access(Name name, TypeSymbol location) {
4164 if (!sym.kind.isResolutionError() && sym.kind.matches(KindSelector.TYP))
4165 return types.createErrorType(name, location, sym.type).tsym;
4166 else
4167 return sym;
4168 }
4169 }
4170
4171 class BadRestrictedTypeError extends ResolveError {
4172 private final Name typeName;
4173 BadRestrictedTypeError(Name typeName) {
4174 super(Kind.BAD_RESTRICTED_TYPE, "bad var use");
4175 this.typeName = typeName;
4176 }
4177
4178 @Override
4179 JCDiagnostic getDiagnostic(DiagnosticType dkind, DiagnosticPosition pos, Symbol location, Type site, Name name, List<Type> argtypes, List<Type> typeargtypes) {
4180 return diags.create(dkind, log.currentSource(), pos, "illegal.ref.to.restricted.type", typeName);
4181 }
4182 }
4183
4184 /**
4185 * InvalidSymbolError error class indicating that a symbol matching a
4186 * given name does not exists in a given site.
4187 */
4188 class SymbolNotFoundError extends ResolveError {
4189
4190 SymbolNotFoundError(Kind kind) {
4191 this(kind, "symbol not found error");
4192 }
4193
4194 SymbolNotFoundError(Kind kind, String debugName) {
4195 super(kind, debugName);
4196 }
4197
4198 @Override
4199 JCDiagnostic getDiagnostic(JCDiagnostic.DiagnosticType dkind,
4200 DiagnosticPosition pos,
4201 Symbol location,
4202 Type site,
4203 Name name,
4204 List<Type> argtypes,
4205 List<Type> typeargtypes) {
4206 argtypes = argtypes == null ? List.nil() : argtypes;
4207 typeargtypes = typeargtypes == null ? List.nil() : typeargtypes;
4208 if (name == names.error)
4209 return null;
4210
4211 boolean hasLocation = false;
4212 if (location == null) {
4213 location = site.tsym;
4214 }
4215 if (!location.name.isEmpty()) {
4216 if (location.kind == PCK && !site.tsym.exists() && location.name != names.java) {
4217 return diags.create(dkind, log.currentSource(), pos,
4218 "doesnt.exist", location);
4219 }
4220 hasLocation = !location.name.equals(names._this) &&
4221 !location.name.equals(names._super);
4222 }
4223 boolean isConstructor = name == names.init;
4224 KindName kindname = isConstructor ? KindName.CONSTRUCTOR : kind.absentKind();
4225 Name idname = isConstructor ? site.tsym.name : name;
4226 String errKey = getErrorKey(kindname, typeargtypes.nonEmpty(), hasLocation);
4227 if (hasLocation) {
4228 return diags.create(dkind, log.currentSource(), pos,
4229 errKey, kindname, idname, //symbol kindname, name
4230 typeargtypes, args(argtypes), //type parameters and arguments (if any)
4231 getLocationDiag(location, site)); //location kindname, type
4232 }
4233 else {
4234 return diags.create(dkind, log.currentSource(), pos,
4235 errKey, kindname, idname, //symbol kindname, name
4236 typeargtypes, args(argtypes)); //type parameters and arguments (if any)
4237 }
4238 }
4239 //where
4240 private Object args(List<Type> args) {
4241 return args.isEmpty() ? args : methodArguments(args);
4242 }
4243
4244 private String getErrorKey(KindName kindname, boolean hasTypeArgs, boolean hasLocation) {
4245 String key = "cant.resolve";
4246 String suffix = hasLocation ? ".location" : "";
4247 switch (kindname) {
4248 case METHOD:
4249 case CONSTRUCTOR: {
4250 suffix += ".args";
4251 suffix += hasTypeArgs ? ".params" : "";
4252 }
4253 }
4254 return key + suffix;
4255 }
4256 private JCDiagnostic getLocationDiag(Symbol location, Type site) {
4257 if (location.kind == VAR) {
4258 return diags.fragment(Fragments.Location1(kindName(location),
4259 location,
4260 location.type));
4261 } else {
4262 return diags.fragment(Fragments.Location(typeKindName(site),
4263 site,
4264 null));
4265 }
4266 }
4267 }
4268
4269 /**
4270 * InvalidSymbolError error class indicating that a given symbol
4271 * (either a method, a constructor or an operand) is not applicable
4272 * given an actual arguments/type argument list.
4273 */
4274 class InapplicableSymbolError extends ResolveError {
4275
4276 protected MethodResolutionContext resolveContext;
4277
4278 InapplicableSymbolError(MethodResolutionContext context) {
4279 this(WRONG_MTH, "inapplicable symbol error", context);
4280 }
4281
4282 protected InapplicableSymbolError(Kind kind, String debugName, MethodResolutionContext context) {
4283 super(kind, debugName);
4284 this.resolveContext = context;
4285 }
4286
4287 @Override
4288 public String toString() {
4289 return super.toString();
4290 }
4291
4292 @Override
4293 public boolean exists() {
4294 return true;
4295 }
4296
4297 @Override
4298 JCDiagnostic getDiagnostic(JCDiagnostic.DiagnosticType dkind,
4299 DiagnosticPosition pos,
4300 Symbol location,
4301 Type site,
4302 Name name,
4303 List<Type> argtypes,
4304 List<Type> typeargtypes) {
4305 if (name == names.error)
4306 return null;
4307
4308 Pair<Symbol, JCDiagnostic> c = errCandidate();
4309 Symbol ws = c.fst.asMemberOf(site, types);
4310 UnaryOperator<JCDiagnostic> rewriter = compactMethodDiags ?
4311 d -> MethodResolutionDiagHelper.rewrite(diags, pos, log.currentSource(), dkind, c.snd) : null;
4312
4313 // If the problem is due to type arguments, then the method parameters aren't relevant,
4314 // so use the error message that omits them to avoid confusion.
4315 switch (c.snd.getCode()) {
4316 case "compiler.misc.wrong.number.type.args":
4317 case "compiler.misc.explicit.param.do.not.conform.to.bounds":
4318 return diags.create(dkind, log.currentSource(), pos,
4319 "cant.apply.symbol.noargs",
4320 rewriter,
4321 kindName(ws),
4322 ws.name == names.init ? ws.owner.name : ws.name,
4323 ws.owner.type,
4324 c.snd);
4325 default:
4326 // Avoid saying "constructor Array in class Array"
4327 if (ws.owner == syms.arrayClass && ws.name == names.init) {
4328 return diags.create(dkind, log.currentSource(), pos,
4329 "cant.apply.array.ctor",
4330 rewriter,
4331 methodArguments(ws.type.getParameterTypes()),
4332 methodArguments(argtypes),
4333 c.snd);
4334 }
4335 return diags.create(dkind, log.currentSource(), pos,
4336 "cant.apply.symbol",
4337 rewriter,
4338 kindName(ws),
4339 ws.name == names.init ? ws.owner.name : ws.name,
4340 methodArguments(ws.type.getParameterTypes()),
4341 methodArguments(argtypes),
4342 kindName(ws.owner),
4343 ws.owner.type,
4344 c.snd);
4345 }
4346 }
4347
4348 @Override
4349 public Symbol access(Name name, TypeSymbol location) {
4350 Pair<Symbol, JCDiagnostic> cand = errCandidate();
4351 TypeSymbol errSymbol = types.createErrorType(name, location, cand != null ? cand.fst.type : syms.errSymbol.type).tsym;
4352 if (cand != null) {
4353 attrRecover.wrongMethodSymbolCandidate(errSymbol, cand.fst, cand.snd);
4354 }
4355 return errSymbol;
4356 }
4357
4358 protected Pair<Symbol, JCDiagnostic> errCandidate() {
4359 Candidate bestSoFar = null;
4360 for (Candidate c : resolveContext.candidates) {
4361 if (c.isApplicable()) continue;
4362 bestSoFar = c;
4363 }
4364 Assert.checkNonNull(bestSoFar);
4365 return new Pair<>(bestSoFar.sym, bestSoFar.details);
4366 }
4367 }
4368
4369 /**
4370 * ResolveError error class indicating that a symbol (either methods, constructors or operand)
4371 * is not applicable given an actual arguments/type argument list.
4372 */
4373 class InapplicableSymbolsError extends InapplicableSymbolError {
4374
4375 InapplicableSymbolsError(MethodResolutionContext context) {
4376 super(WRONG_MTHS, "inapplicable symbols", context);
4377 }
4378
4379 @Override
4380 JCDiagnostic getDiagnostic(JCDiagnostic.DiagnosticType dkind,
4381 DiagnosticPosition pos,
4382 Symbol location,
4383 Type site,
4384 Name name,
4385 List<Type> argtypes,
4386 List<Type> typeargtypes) {
4387 Map<Symbol, JCDiagnostic> candidatesMap = mapCandidates();
4388 Map<Symbol, JCDiagnostic> filteredCandidates = compactMethodDiags ?
4389 filterCandidates(candidatesMap) :
4390 mapCandidates();
4391 if (filteredCandidates.isEmpty()) {
4392 filteredCandidates = candidatesMap;
4393 }
4394 boolean truncatedDiag = candidatesMap.size() != filteredCandidates.size();
4395 if (filteredCandidates.size() > 1) {
4396 JCDiagnostic err = diags.create(dkind,
4397 null,
4398 truncatedDiag ?
4399 EnumSet.of(DiagnosticFlag.COMPRESSED) :
4400 EnumSet.noneOf(DiagnosticFlag.class),
4401 log.currentSource(),
4402 pos,
4403 "cant.apply.symbols",
4404 name == names.init ? KindName.CONSTRUCTOR : kind.absentKind(),
4405 name == names.init ? site.tsym.name : name,
4406 methodArguments(argtypes));
4407 return new JCDiagnostic.MultilineDiagnostic(err, candidateDetails(filteredCandidates, site));
4408 } else if (filteredCandidates.size() == 1) {
4409 Map.Entry<Symbol, JCDiagnostic> _e =
4410 filteredCandidates.entrySet().iterator().next();
4411 final Pair<Symbol, JCDiagnostic> p = new Pair<>(_e.getKey(), _e.getValue());
4412 JCDiagnostic d = new InapplicableSymbolError(resolveContext) {
4413 @Override
4414 protected Pair<Symbol, JCDiagnostic> errCandidate() {
4415 return p;
4416 }
4417 }.getDiagnostic(dkind, pos,
4418 location, site, name, argtypes, typeargtypes);
4419 if (truncatedDiag) {
4420 d.setFlag(DiagnosticFlag.COMPRESSED);
4421 }
4422 return d;
4423 } else {
4424 return new SymbolNotFoundError(ABSENT_MTH).getDiagnostic(dkind, pos,
4425 location, site, name, argtypes, typeargtypes);
4426 }
4427 }
4428 //where
4429 private Map<Symbol, JCDiagnostic> mapCandidates() {
4430 MostSpecificMap candidates = new MostSpecificMap();
4431 for (Candidate c : resolveContext.candidates) {
4432 if (c.isApplicable()) continue;
4433 candidates.put(c);
4434 }
4435 return candidates;
4436 }
4437
4438 @SuppressWarnings("serial")
4439 private class MostSpecificMap extends LinkedHashMap<Symbol, JCDiagnostic> {
4440 private void put(Candidate c) {
4441 ListBuffer<Symbol> overridden = new ListBuffer<>();
4442 for (Symbol s : keySet()) {
4443 if (s == c.sym) {
4444 continue;
4445 }
4446 if (c.sym.overrides(s, (TypeSymbol)s.owner, types, false)) {
4447 overridden.add(s);
4448 } else if (s.overrides(c.sym, (TypeSymbol)c.sym.owner, types, false)) {
4449 return;
4450 }
4451 }
4452 for (Symbol s : overridden) {
4453 remove(s);
4454 }
4455 put(c.sym, c.details);
4456 }
4457 }
4458
4459 Map<Symbol, JCDiagnostic> filterCandidates(Map<Symbol, JCDiagnostic> candidatesMap) {
4460 Map<Symbol, JCDiagnostic> candidates = new LinkedHashMap<>();
4461 for (Map.Entry<Symbol, JCDiagnostic> _entry : candidatesMap.entrySet()) {
4462 JCDiagnostic d = _entry.getValue();
4463 if (!new Template(MethodCheckDiag.ARITY_MISMATCH.regex()).matches(d)) {
4464 candidates.put(_entry.getKey(), d);
4465 }
4466 }
4467 return candidates;
4468 }
4469
4470 private List<JCDiagnostic> candidateDetails(Map<Symbol, JCDiagnostic> candidatesMap, Type site) {
4471 List<JCDiagnostic> details = List.nil();
4472 for (Map.Entry<Symbol, JCDiagnostic> _entry : candidatesMap.entrySet()) {
4473 Symbol sym = _entry.getKey();
4474 JCDiagnostic detailDiag =
4475 diags.fragment(Fragments.InapplicableMethod(Kinds.kindName(sym),
4476 sym.location(site, types),
4477 sym.asMemberOf(site, types),
4478 _entry.getValue()));
4479 details = details.prepend(detailDiag);
4480 }
4481 //typically members are visited in reverse order (see Scope)
4482 //so we need to reverse the candidate list so that candidates
4483 //conform to source order
4484 return details;
4485 }
4486
4487 @Override
4488 protected Pair<Symbol, JCDiagnostic> errCandidate() {
4489 Map<Symbol, JCDiagnostic> candidatesMap = mapCandidates();
4490 Map<Symbol, JCDiagnostic> filteredCandidates = filterCandidates(candidatesMap);
4491 if (filteredCandidates.size() == 1) {
4492 return Pair.of(filteredCandidates.keySet().iterator().next(),
4493 filteredCandidates.values().iterator().next());
4494 }
4495 return null;
4496 }
4497 }
4498
4499 /**
4500 * DiamondError error class indicating that a constructor symbol is not applicable
4501 * given an actual arguments/type argument list using diamond inference.
4502 */
4503 class DiamondError extends InapplicableSymbolError {
4504
4505 Symbol sym;
4506
4507 public DiamondError(Symbol sym, MethodResolutionContext context) {
4508 super(sym.kind, "diamondError", context);
4509 this.sym = sym;
4510 }
4511
4512 JCDiagnostic getDetails() {
4513 return (sym.kind == WRONG_MTH) ?
4514 ((InapplicableSymbolError)sym.baseSymbol()).errCandidate().snd :
4515 null;
4516 }
4517
4518 @Override
4519 JCDiagnostic getDiagnostic(DiagnosticType dkind, DiagnosticPosition pos,
4520 Symbol location, Type site, Name name, List<Type> argtypes, List<Type> typeargtypes) {
4521 JCDiagnostic details = getDetails();
4522 if (details != null && compactMethodDiags) {
4523 JCDiagnostic simpleDiag =
4524 MethodResolutionDiagHelper.rewrite(diags, pos, log.currentSource(), dkind, details);
4525 if (simpleDiag != null) {
4526 return simpleDiag;
4527 }
4528 }
4529 String key = details == null ?
4530 "cant.apply.diamond" :
4531 "cant.apply.diamond.1";
4532 return diags.create(dkind, log.currentSource(), pos, key,
4533 Fragments.Diamond(site.tsym), details);
4534 }
4535 }
4536
4537 /**
4538 * An InvalidSymbolError error class indicating that a symbol is not
4539 * accessible from a given site
4540 */
4541 class AccessError extends InvalidSymbolError {
4542
4543 private Env<AttrContext> env;
4544 private Type site;
4545
4546 AccessError(Env<AttrContext> env, Type site, Symbol sym) {
4547 super(HIDDEN, sym, "access error");
4548 this.env = env;
4549 this.site = site;
4550 }
4551
4552 @Override
4553 public boolean exists() {
4554 return false;
4555 }
4556
4557 @Override
4558 JCDiagnostic getDiagnostic(JCDiagnostic.DiagnosticType dkind,
4559 DiagnosticPosition pos,
4560 Symbol location,
4561 Type site,
4562 Name name,
4563 List<Type> argtypes,
4564 List<Type> typeargtypes) {
4565 if (sym.name == names.init && sym.owner != site.tsym) {
4566 return new SymbolNotFoundError(ABSENT_MTH).getDiagnostic(dkind,
4567 pos, location, site, name, argtypes, typeargtypes);
4568 }
4569 else if ((sym.flags() & PUBLIC) != 0
4570 || (env != null && this.site != null
4571 && !isAccessible(env, this.site))) {
4572 if (sym.owner.kind == PCK) {
4573 return diags.create(dkind, log.currentSource(),
4574 pos, "not.def.access.package.cant.access",
4575 sym, sym.location(), inaccessiblePackageReason(env, sym.packge()));
4576 } else if ( sym.packge() != syms.rootPackage
4577 && !symbolPackageVisible(env, sym)) {
4578 return diags.create(dkind, log.currentSource(),
4579 pos, "not.def.access.class.intf.cant.access.reason",
4580 sym, sym.location(), sym.location().packge(),
4581 inaccessiblePackageReason(env, sym.packge()));
4582 } else {
4583 return diags.create(dkind, log.currentSource(),
4584 pos, "not.def.access.class.intf.cant.access",
4585 sym, sym.location());
4586 }
4587 }
4588 else if ((sym.flags() & (PRIVATE | PROTECTED)) != 0) {
4589 return diags.create(dkind, log.currentSource(),
4590 pos, "report.access", sym,
4591 asFlagSet(sym.flags() & (PRIVATE | PROTECTED)),
4592 sym.location());
4593 }
4594 else {
4595 return diags.create(dkind, log.currentSource(),
4596 pos, "not.def.public.cant.access", sym, sym.location());
4597 }
4598 }
4599
4600 private String toString(Type type) {
4601 StringBuilder sb = new StringBuilder();
4602 sb.append(type);
4603 if (type != null) {
4604 sb.append("[tsym:").append(type.tsym);
4605 if (type.tsym != null)
4606 sb.append("packge:").append(type.tsym.packge());
4607 sb.append("]");
4608 }
4609 return sb.toString();
4610 }
4611 }
4612
4613 class InvisibleSymbolError extends InvalidSymbolError {
4614
4615 private final Env<AttrContext> env;
4616 private final boolean suppressError;
4617
4618 InvisibleSymbolError(Env<AttrContext> env, boolean suppressError, Symbol sym) {
4619 super(HIDDEN, sym, "invisible class error");
4620 this.env = env;
4621 this.suppressError = suppressError;
4622 this.name = sym.name;
4623 }
4624
4625 @Override
4626 JCDiagnostic getDiagnostic(JCDiagnostic.DiagnosticType dkind,
4627 DiagnosticPosition pos,
4628 Symbol location,
4629 Type site,
4630 Name name,
4631 List<Type> argtypes,
4632 List<Type> typeargtypes) {
4633 if (suppressError)
4634 return null;
4635
4636 if (sym.kind == PCK) {
4637 JCDiagnostic details = inaccessiblePackageReason(env, sym.packge());
4638 return diags.create(dkind, log.currentSource(),
4639 pos, "package.not.visible", sym, details);
4640 }
4641
4642 JCDiagnostic details = inaccessiblePackageReason(env, sym.packge());
4643
4644 if (pos.getTree() != null) {
4645 Symbol o = sym;
4646 JCTree tree = pos.getTree();
4647
4648 while (o.kind != PCK && tree.hasTag(SELECT)) {
4649 o = o.owner;
4650 tree = ((JCFieldAccess) tree).selected;
4651 }
4652
4653 if (o.kind == PCK) {
4654 pos = tree.pos();
4655
4656 return diags.create(dkind, log.currentSource(),
4657 pos, "package.not.visible", o, details);
4658 }
4659 }
4660
4661 return diags.create(dkind, log.currentSource(),
4662 pos, "not.def.access.package.cant.access", sym, sym.packge(), details);
4663 }
4664 }
4665
4666 JCDiagnostic inaccessiblePackageReason(Env<AttrContext> env, PackageSymbol sym) {
4667 //no dependency:
4668 if (!env.toplevel.modle.readModules.contains(sym.modle)) {
4669 //does not read:
4670 if (sym.modle != syms.unnamedModule) {
4671 if (env.toplevel.modle != syms.unnamedModule) {
4672 return diags.fragment(Fragments.NotDefAccessDoesNotRead(env.toplevel.modle,
4673 sym,
4674 sym.modle));
4675 } else {
4676 return diags.fragment(Fragments.NotDefAccessDoesNotReadFromUnnamed(sym,
4677 sym.modle));
4678 }
4679 } else {
4680 return diags.fragment(Fragments.NotDefAccessDoesNotReadUnnamed(sym,
4681 env.toplevel.modle));
4682 }
4683 } else {
4684 if (sym.packge().modle.exports.stream().anyMatch(e -> e.packge == sym)) {
4685 //not exported to this module:
4686 if (env.toplevel.modle != syms.unnamedModule) {
4687 return diags.fragment(Fragments.NotDefAccessNotExportedToModule(sym,
4688 sym.modle,
4689 env.toplevel.modle));
4690 } else {
4691 return diags.fragment(Fragments.NotDefAccessNotExportedToModuleFromUnnamed(sym,
4692 sym.modle));
4693 }
4694 } else {
4695 //not exported:
4696 if (env.toplevel.modle != syms.unnamedModule) {
4697 return diags.fragment(Fragments.NotDefAccessNotExported(sym,
4698 sym.modle));
4699 } else {
4700 return diags.fragment(Fragments.NotDefAccessNotExportedFromUnnamed(sym,
4701 sym.modle));
4702 }
4703 }
4704 }
4705 }
4706
4707 /**
4708 * InvalidSymbolError error class indicating that an instance member
4709 * has erroneously been accessed from a static context.
4710 */
4711 class StaticError extends InvalidSymbolError {
4712
4713 StaticError(Symbol sym) {
4714 this(sym, "static error");
4715 }
4716
4717 StaticError(Symbol sym, String debugName) {
4718 super(STATICERR, sym, debugName);
4719 }
4720
4721 @Override
4722 JCDiagnostic getDiagnostic(JCDiagnostic.DiagnosticType dkind,
4723 DiagnosticPosition pos,
4724 Symbol location,
4725 Type site,
4726 Name name,
4727 List<Type> argtypes,
4728 List<Type> typeargtypes) {
4729 Symbol errSym = ((sym.kind == TYP && sym.type.hasTag(CLASS))
4730 ? types.erasure(sym.type).tsym
4731 : sym);
4732 return diags.create(dkind, log.currentSource(), pos,
4733 "non-static.cant.be.ref", kindName(sym), errSym);
4734 }
4735 }
4736
4737 /**
4738 * Specialization of {@link InvalidSymbolError} for illegal
4739 * early accesses within a constructor prologue.
4740 */
4741 class RefBeforeCtorCalledError extends StaticError {
4742
4743 RefBeforeCtorCalledError(Symbol sym) {
4744 super(sym, "prologue error");
4745 }
4746
4747 @Override
4748 JCDiagnostic getDiagnostic(JCDiagnostic.DiagnosticType dkind,
4749 DiagnosticPosition pos,
4750 Symbol location,
4751 Type site,
4752 Name name,
4753 List<Type> argtypes,
4754 List<Type> typeargtypes) {
4755 Symbol errSym = ((sym.kind == TYP && sym.type.hasTag(CLASS))
4756 ? types.erasure(sym.type).tsym
4757 : sym);
4758 return diags.create(dkind, log.currentSource(), pos,
4759 "cant.ref.before.ctor.called", errSym);
4760 }
4761 }
4762
4763 /**
4764 * InvalidSymbolError error class indicating that a pair of symbols
4765 * (either methods, constructors or operands) are ambiguous
4766 * given an actual arguments/type argument list.
4767 */
4768 class AmbiguityError extends ResolveError {
4769
4770 /** The other maximally specific symbol */
4771 List<Symbol> ambiguousSyms = List.nil();
4772
4773 @Override
4774 public boolean exists() {
4775 return true;
4776 }
4777
4778 AmbiguityError(Symbol sym1, Symbol sym2) {
4779 super(AMBIGUOUS, "ambiguity error");
4780 ambiguousSyms = flatten(sym2).appendList(flatten(sym1));
4781 }
4782
4783 private List<Symbol> flatten(Symbol sym) {
4784 if (sym.kind == AMBIGUOUS) {
4785 return ((AmbiguityError)sym.baseSymbol()).ambiguousSyms;
4786 } else {
4787 return List.of(sym);
4788 }
4789 }
4790
4791 AmbiguityError addAmbiguousSymbol(Symbol s) {
4792 ambiguousSyms = ambiguousSyms.prepend(s);
4793 return this;
4794 }
4795
4796 @Override
4797 JCDiagnostic getDiagnostic(JCDiagnostic.DiagnosticType dkind,
4798 DiagnosticPosition pos,
4799 Symbol location,
4800 Type site,
4801 Name name,
4802 List<Type> argtypes,
4803 List<Type> typeargtypes) {
4804 List<Symbol> diagSyms = ambiguousSyms.reverse();
4805 Symbol s1 = diagSyms.head;
4806 Symbol s2 = diagSyms.tail.head;
4807 Name sname = s1.name;
4808 if (sname == names.init) sname = s1.owner.name;
4809 return diags.create(dkind, log.currentSource(),
4810 pos, "ref.ambiguous", sname,
4811 kindName(s1),
4812 s1,
4813 s1.location(site, types),
4814 kindName(s2),
4815 s2,
4816 s2.location(site, types));
4817 }
4818
4819 /**
4820 * If multiple applicable methods are found during overload and none of them
4821 * is more specific than the others, attempt to merge their signatures.
4822 */
4823 Symbol mergeAbstracts(Type site) {
4824 List<Symbol> ambiguousInOrder = ambiguousSyms.reverse();
4825 return types.mergeAbstracts(ambiguousInOrder, site, true).orElse(this);
4826 }
4827
4828 @Override
4829 protected Symbol access(Name name, TypeSymbol location) {
4830 Symbol firstAmbiguity = ambiguousSyms.last();
4831 return firstAmbiguity.kind == TYP ?
4832 types.createErrorType(name, location, firstAmbiguity.type).tsym :
4833 firstAmbiguity;
4834 }
4835 }
4836
4837 class BadVarargsMethod extends ResolveError {
4838
4839 ResolveError delegatedError;
4840
4841 BadVarargsMethod(ResolveError delegatedError) {
4842 super(delegatedError.kind, "badVarargs");
4843 this.delegatedError = delegatedError;
4844 }
4845
4846 @Override
4847 public Symbol baseSymbol() {
4848 return delegatedError.baseSymbol();
4849 }
4850
4851 @Override
4852 protected Symbol access(Name name, TypeSymbol location) {
4853 return delegatedError.access(name, location);
4854 }
4855
4856 @Override
4857 public boolean exists() {
4858 return true;
4859 }
4860
4861 @Override
4862 JCDiagnostic getDiagnostic(DiagnosticType dkind, DiagnosticPosition pos, Symbol location, Type site, Name name, List<Type> argtypes, List<Type> typeargtypes) {
4863 return delegatedError.getDiagnostic(dkind, pos, location, site, name, argtypes, typeargtypes);
4864 }
4865 }
4866
4867 /**
4868 * BadMethodReferenceError error class indicating that a method reference symbol has been found,
4869 * but with the wrong staticness.
4870 */
4871 class BadMethodReferenceError extends StaticError {
4872
4873 boolean unboundLookup;
4874
4875 public BadMethodReferenceError(Symbol sym, boolean unboundLookup) {
4876 super(sym, "bad method ref error");
4877 this.unboundLookup = unboundLookup;
4878 }
4879
4880 @Override
4881 JCDiagnostic getDiagnostic(DiagnosticType dkind, DiagnosticPosition pos, Symbol location, Type site, Name name, List<Type> argtypes, List<Type> typeargtypes) {
4882 final String key;
4883 if (!unboundLookup) {
4884 key = "bad.static.method.in.bound.lookup";
4885 } else if (sym.isStatic()) {
4886 key = "bad.static.method.in.unbound.lookup";
4887 } else {
4888 key = "bad.instance.method.in.unbound.lookup";
4889 }
4890 return sym.kind.isResolutionError() ?
4891 ((ResolveError)sym).getDiagnostic(dkind, pos, location, site, name, argtypes, typeargtypes) :
4892 diags.create(dkind, log.currentSource(), pos, key, Kinds.kindName(sym), sym);
4893 }
4894 }
4895
4896 /**
4897 * BadConstructorReferenceError error class indicating that a constructor reference symbol has been found,
4898 * but pointing to a class for which an enclosing instance is not available.
4899 */
4900 class BadConstructorReferenceError extends InvalidSymbolError {
4901
4902 public BadConstructorReferenceError(Symbol sym) {
4903 super(MISSING_ENCL, sym, "BadConstructorReferenceError");
4904 }
4905
4906 @Override
4907 JCDiagnostic getDiagnostic(DiagnosticType dkind, DiagnosticPosition pos, Symbol location, Type site, Name name, List<Type> argtypes, List<Type> typeargtypes) {
4908 return diags.create(dkind, log.currentSource(), pos,
4909 "cant.access.inner.cls.constr", site.tsym.name, argtypes, site.getEnclosingType());
4910 }
4911 }
4912
4913 class BadClassFileError extends InvalidSymbolError {
4914
4915 private final CompletionFailure ex;
4916
4917 public BadClassFileError(CompletionFailure ex) {
4918 super(HIDDEN, ex.sym, "BadClassFileError");
4919 this.name = sym.name;
4920 this.ex = ex;
4921 }
4922
4923 @Override
4924 JCDiagnostic getDiagnostic(DiagnosticType dkind, DiagnosticPosition pos, Symbol location, Type site, Name name, List<Type> argtypes, List<Type> typeargtypes) {
4925 JCDiagnostic d = diags.create(dkind, log.currentSource(), pos,
4926 "cant.access", ex.sym, ex.getDetailValue());
4927
4928 d.setFlag(DiagnosticFlag.NON_DEFERRABLE);
4929 return d;
4930 }
4931
4932 }
4933
4934 /**
4935 * Helper class for method resolution diagnostic simplification.
4936 * Certain resolution diagnostic are rewritten as simpler diagnostic
4937 * where the enclosing resolution diagnostic (i.e. 'inapplicable method')
4938 * is stripped away, as it doesn't carry additional info. The logic
4939 * for matching a given diagnostic is given in terms of a template
4940 * hierarchy: a diagnostic template can be specified programmatically,
4941 * so that only certain diagnostics are matched. Each templete is then
4942 * associated with a rewriter object that carries out the task of rewtiting
4943 * the diagnostic to a simpler one.
4944 */
4945 static class MethodResolutionDiagHelper {
4946
4947 /**
4948 * A diagnostic rewriter transforms a method resolution diagnostic
4949 * into a simpler one
4950 */
4951 interface DiagnosticRewriter {
4952 JCDiagnostic rewriteDiagnostic(JCDiagnostic.Factory diags,
4953 DiagnosticPosition preferredPos, DiagnosticSource preferredSource,
4954 DiagnosticType preferredKind, JCDiagnostic d);
4955 }
4956
4957 /**
4958 * A diagnostic template is made up of two ingredients: (i) a regular
4959 * expression for matching a diagnostic key and (ii) a list of sub-templates
4960 * for matching diagnostic arguments.
4961 */
4962 static class Template {
4963
4964 /** regex used to match diag key */
4965 String regex;
4966
4967 /** templates used to match diagnostic args */
4968 Template[] subTemplates;
4969
4970 Template(String key, Template... subTemplates) {
4971 this.regex = key;
4972 this.subTemplates = subTemplates;
4973 }
4974
4975 /**
4976 * Returns true if the regex matches the diagnostic key and if
4977 * all diagnostic arguments are matches by corresponding sub-templates.
4978 */
4979 boolean matches(Object o) {
4980 JCDiagnostic d = (JCDiagnostic)o;
4981 Object[] args = d.getArgs();
4982 if (!d.getCode().matches(regex) ||
4983 subTemplates.length != d.getArgs().length) {
4984 return false;
4985 }
4986 for (int i = 0; i < args.length ; i++) {
4987 if (!subTemplates[i].matches(args[i])) {
4988 return false;
4989 }
4990 }
4991 return true;
4992 }
4993 }
4994
4995 /**
4996 * Common rewriter for all argument mismatch simplifications.
4997 */
4998 static class ArgMismatchRewriter implements DiagnosticRewriter {
4999
5000 /** the index of the subdiagnostic to be used as primary. */
5001 int causeIndex;
5002
5003 public ArgMismatchRewriter(int causeIndex) {
5004 this.causeIndex = causeIndex;
5005 }
5006
5007 @Override
5008 public JCDiagnostic rewriteDiagnostic(JCDiagnostic.Factory diags,
5009 DiagnosticPosition preferredPos, DiagnosticSource preferredSource,
5010 DiagnosticType preferredKind, JCDiagnostic d) {
5011 JCDiagnostic cause = (JCDiagnostic)d.getArgs()[causeIndex];
5012 DiagnosticPosition pos = d.getDiagnosticPosition();
5013 if (pos == null) {
5014 pos = preferredPos;
5015 }
5016 return diags.create(preferredKind, preferredSource, pos,
5017 "prob.found.req", cause);
5018 }
5019 }
5020
5021 /** a dummy template that match any diagnostic argument */
5022 static final Template skip = new Template("") {
5023 @Override
5024 boolean matches(Object d) {
5025 return true;
5026 }
5027 };
5028
5029 /** template for matching inference-free arguments mismatch failures */
5030 static final Template argMismatchTemplate = new Template(MethodCheckDiag.ARG_MISMATCH.regex(), skip);
5031
5032 /** template for matching inference related arguments mismatch failures */
5033 static final Template inferArgMismatchTemplate = new Template(MethodCheckDiag.ARG_MISMATCH.regex(), skip, skip) {
5034 @Override
5035 boolean matches(Object o) {
5036 if (!super.matches(o)) {
5037 return false;
5038 }
5039 JCDiagnostic d = (JCDiagnostic)o;
5040 @SuppressWarnings("unchecked")
5041 List<Type> tvars = (List<Type>)d.getArgs()[0];
5042 return !containsAny(d, tvars);
5043 }
5044
5045 BiPredicate<Object, List<Type>> containsPredicate = (o, ts) -> {
5046 if (o instanceof Type type) {
5047 return type.containsAny(ts);
5048 } else if (o instanceof JCDiagnostic diagnostic) {
5049 return containsAny(diagnostic, ts);
5050 } else {
5051 return false;
5052 }
5053 };
5054
5055 boolean containsAny(JCDiagnostic d, List<Type> ts) {
5056 return Stream.of(d.getArgs())
5057 .anyMatch(o -> containsPredicate.test(o, ts));
5058 }
5059 };
5060
5061 /** rewriter map used for method resolution simplification */
5062 static final Map<Template, DiagnosticRewriter> rewriters = new LinkedHashMap<>();
5063
5064 static {
5065 rewriters.put(argMismatchTemplate, new ArgMismatchRewriter(0));
5066 rewriters.put(inferArgMismatchTemplate, new ArgMismatchRewriter(1));
5067 }
5068
5069 /**
5070 * Main entry point for diagnostic rewriting - given a diagnostic, see if any templates matches it,
5071 * and rewrite it accordingly.
5072 */
5073 static JCDiagnostic rewrite(JCDiagnostic.Factory diags, DiagnosticPosition pos, DiagnosticSource source,
5074 DiagnosticType dkind, JCDiagnostic d) {
5075 for (Map.Entry<Template, DiagnosticRewriter> _entry : rewriters.entrySet()) {
5076 if (_entry.getKey().matches(d)) {
5077 JCDiagnostic simpleDiag =
5078 _entry.getValue().rewriteDiagnostic(diags, pos, source, dkind, d);
5079 simpleDiag.setFlag(DiagnosticFlag.COMPRESSED);
5080 return simpleDiag;
5081 }
5082 }
5083 return null;
5084 }
5085 }
5086
5087 enum MethodResolutionPhase {
5088 BASIC(false, false),
5089 BOX(true, false),
5090 VARARITY(true, true) {
5091 @Override
5092 public Symbol mergeResults(Symbol bestSoFar, Symbol sym) {
5093 //Check invariants (see {@code LookupHelper.shouldStop})
5094 Assert.check(bestSoFar.kind.isResolutionError() && bestSoFar.kind != AMBIGUOUS);
5095 if (!sym.kind.isResolutionError()) {
5096 //varargs resolution successful
5097 return sym;
5098 } else {
5099 //pick best error
5100 switch (bestSoFar.kind) {
5101 case WRONG_MTH:
5102 case WRONG_MTHS:
5103 //Override previous errors if they were caused by argument mismatch.
5104 //This generally means preferring current symbols - but we need to pay
5105 //attention to the fact that the varargs lookup returns 'less' candidates
5106 //than the previous rounds, and adjust that accordingly.
5107 switch (sym.kind) {
5108 case WRONG_MTH:
5109 //if the previous round matched more than one method, return that
5110 //result instead
5111 return bestSoFar.kind == WRONG_MTHS ?
5112 bestSoFar : sym;
5113 case ABSENT_MTH:
5114 //do not override erroneous symbol if the arity lookup did not
5115 //match any method
5116 return bestSoFar;
5117 case WRONG_MTHS:
5118 default:
5119 //safe to override
5120 return sym;
5121 }
5122 default:
5123 //otherwise, return first error
5124 return bestSoFar;
5125 }
5126 }
5127 }
5128 };
5129
5130 final boolean isBoxingRequired;
5131 final boolean isVarargsRequired;
5132
5133 MethodResolutionPhase(boolean isBoxingRequired, boolean isVarargsRequired) {
5134 this.isBoxingRequired = isBoxingRequired;
5135 this.isVarargsRequired = isVarargsRequired;
5136 }
5137
5138 public boolean isBoxingRequired() {
5139 return isBoxingRequired;
5140 }
5141
5142 public boolean isVarargsRequired() {
5143 return isVarargsRequired;
5144 }
5145
5146 public Symbol mergeResults(Symbol prev, Symbol sym) {
5147 return sym;
5148 }
5149 }
5150
5151 final List<MethodResolutionPhase> methodResolutionSteps = List.of(BASIC, BOX, VARARITY);
5152
5153 /**
5154 * A resolution context is used to keep track of intermediate results of
5155 * overload resolution, such as list of method that are not applicable
5156 * (used to generate more precise diagnostics) and so on. Resolution contexts
5157 * can be nested - this means that when each overload resolution routine should
5158 * work within the resolution context it created.
5159 */
5160 class MethodResolutionContext {
5161
5162 private List<Candidate> candidates = List.nil();
5163
5164 MethodResolutionPhase step = null;
5165
5166 MethodCheck methodCheck = resolveMethodCheck;
5167
5168 private boolean internalResolution = false;
5169 private DeferredAttr.AttrMode attrMode = DeferredAttr.AttrMode.SPECULATIVE;
5170
5171 void addInapplicableCandidate(Symbol sym, JCDiagnostic details) {
5172 Candidate c = new Candidate(currentResolutionContext.step, sym, details, null);
5173 candidates = candidates.append(c);
5174 }
5175
5176 void addApplicableCandidate(Symbol sym, Type mtype) {
5177 Candidate c = new Candidate(currentResolutionContext.step, sym, null, mtype);
5178 candidates = candidates.append(c);
5179 }
5180
5181 DeferredAttrContext deferredAttrContext(Symbol sym, InferenceContext inferenceContext, ResultInfo pendingResult, Warner warn) {
5182 DeferredAttrContext parent = (pendingResult == null)
5183 ? deferredAttr.emptyDeferredAttrContext
5184 : pendingResult.checkContext.deferredAttrContext();
5185 return deferredAttr.new DeferredAttrContext(attrMode, sym, step,
5186 inferenceContext, parent, warn);
5187 }
5188
5189 /**
5190 * This class represents an overload resolution candidate. There are two
5191 * kinds of candidates: applicable methods and inapplicable methods;
5192 * applicable methods have a pointer to the instantiated method type,
5193 * while inapplicable candidates contain further details about the
5194 * reason why the method has been considered inapplicable.
5195 */
5196 @SuppressWarnings("overrides")
5197 class Candidate {
5198
5199 final MethodResolutionPhase step;
5200 final Symbol sym;
5201 final JCDiagnostic details;
5202 final Type mtype;
5203
5204 private Candidate(MethodResolutionPhase step, Symbol sym, JCDiagnostic details, Type mtype) {
5205 this.step = step;
5206 this.sym = sym;
5207 this.details = details;
5208 this.mtype = mtype;
5209 }
5210
5211 boolean isApplicable() {
5212 return mtype != null;
5213 }
5214 }
5215
5216 DeferredAttr.AttrMode attrMode() {
5217 return attrMode;
5218 }
5219 }
5220
5221 MethodResolutionContext currentResolutionContext = null;
5222 }