1 /*
2 * Copyright (c) 1999, 2024, Oracle and/or its affiliates. All rights reserved.
3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
4 *
5 * This code is free software; you can redistribute it and/or modify it
6 * under the terms of the GNU General Public License version 2 only, as
7 * published by the Free Software Foundation. Oracle designates this
8 * particular file as subject to the "Classpath" exception as provided
9 * by Oracle in the LICENSE file that accompanied this code.
10 *
11 * This code is distributed in the hope that it will be useful, but WITHOUT
12 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
13 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
14 * version 2 for more details (a copy is included in the LICENSE file that
15 * accompanied this code).
16 *
17 * You should have received a copy of the GNU General Public License version
18 * 2 along with this work; if not, write to the Free Software Foundation,
19 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
20 *
21 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
22 * or visit www.oracle.com if you need additional information or have any
23 * questions.
24 */
25
26 package com.sun.tools.javac.comp;
27
28 import com.sun.tools.javac.api.Formattable.LocalizedString;
29 import com.sun.tools.javac.code.*;
30 import com.sun.tools.javac.code.Scope.WriteableScope;
31 import com.sun.tools.javac.code.Source.Feature;
32 import com.sun.tools.javac.code.Symbol.*;
33 import com.sun.tools.javac.code.Type.*;
34 import com.sun.tools.javac.comp.Attr.ResultInfo;
35 import com.sun.tools.javac.comp.Check.CheckContext;
36 import com.sun.tools.javac.comp.DeferredAttr.AttrMode;
37 import com.sun.tools.javac.comp.DeferredAttr.DeferredAttrContext;
38 import com.sun.tools.javac.comp.DeferredAttr.DeferredType;
39 import com.sun.tools.javac.comp.Resolve.MethodResolutionContext.Candidate;
40 import com.sun.tools.javac.comp.Resolve.MethodResolutionDiagHelper.Template;
41 import com.sun.tools.javac.comp.Resolve.ReferenceLookupResult.StaticKind;
42 import com.sun.tools.javac.jvm.*;
43 import com.sun.tools.javac.main.Option;
44 import com.sun.tools.javac.resources.CompilerProperties.Errors;
45 import com.sun.tools.javac.resources.CompilerProperties.Fragments;
46 import com.sun.tools.javac.resources.CompilerProperties.Warnings;
47 import com.sun.tools.javac.tree.*;
48 import com.sun.tools.javac.tree.JCTree.*;
49 import com.sun.tools.javac.tree.JCTree.JCMemberReference.ReferenceKind;
50 import com.sun.tools.javac.tree.JCTree.JCPolyExpression.*;
51 import com.sun.tools.javac.util.*;
52 import com.sun.tools.javac.util.DefinedBy.Api;
53 import com.sun.tools.javac.util.JCDiagnostic.DiagnosticFlag;
54 import com.sun.tools.javac.util.JCDiagnostic.DiagnosticPosition;
55 import com.sun.tools.javac.util.JCDiagnostic.DiagnosticType;
56
57 import java.util.Arrays;
58 import java.util.Collection;
59 import java.util.EnumSet;
60 import java.util.HashSet;
61 import java.util.Iterator;
62 import java.util.LinkedHashMap;
63 import java.util.Map;
64 import java.util.Set;
65 import java.util.function.BiFunction;
66 import java.util.function.BiPredicate;
67 import java.util.function.Function;
68 import java.util.function.Predicate;
69 import java.util.function.UnaryOperator;
70 import java.util.stream.Stream;
71 import java.util.stream.StreamSupport;
72
73 import javax.lang.model.element.ElementVisitor;
74
75 import static com.sun.tools.javac.code.Flags.*;
76 import static com.sun.tools.javac.code.Flags.BLOCK;
77 import static com.sun.tools.javac.code.Flags.STATIC;
78 import static com.sun.tools.javac.code.Kinds.*;
79 import static com.sun.tools.javac.code.Kinds.Kind.*;
80 import static com.sun.tools.javac.code.TypeTag.*;
81 import static com.sun.tools.javac.comp.Resolve.MethodResolutionPhase.*;
82 import static com.sun.tools.javac.main.Option.DOE;
83 import static com.sun.tools.javac.tree.JCTree.Tag.*;
84 import static com.sun.tools.javac.util.Iterators.createCompoundIterator;
85
86 /** Helper class for name resolution, used mostly by the attribution phase.
87 *
88 * <p><b>This is NOT part of any supported API.
89 * If you write code that depends on this, you do so at your own risk.
90 * This code and its internal interfaces are subject to change or
91 * deletion without notice.</b>
92 */
93 public class Resolve {
94 protected static final Context.Key<Resolve> resolveKey = new Context.Key<>();
95
96 Names names;
97 Log log;
98 Symtab syms;
99 Attr attr;
100 AttrRecover attrRecover;
101 DeferredAttr deferredAttr;
102 Check chk;
103 Infer infer;
104 Preview preview;
105 ClassFinder finder;
106 ModuleFinder moduleFinder;
107 Types types;
108 JCDiagnostic.Factory diags;
109 public final boolean allowModules;
110 public final boolean allowRecords;
111 private final boolean compactMethodDiags;
112 private final boolean allowLocalVariableTypeInference;
113 private final boolean allowYieldStatement;
114 final EnumSet<VerboseResolutionMode> verboseResolutionMode;
115 final boolean dumpMethodReferenceSearchResults;
116 final boolean dumpStacktraceOnError;
117
118 WriteableScope polymorphicSignatureScope;
119
120 @SuppressWarnings("this-escape")
121 protected Resolve(Context context) {
122 context.put(resolveKey, this);
123 syms = Symtab.instance(context);
124
125 varNotFound = new SymbolNotFoundError(ABSENT_VAR);
126 methodNotFound = new SymbolNotFoundError(ABSENT_MTH);
127 typeNotFound = new SymbolNotFoundError(ABSENT_TYP);
128 referenceNotFound = ReferenceLookupResult.error(methodNotFound);
129
130 names = Names.instance(context);
131 log = Log.instance(context);
132 attr = Attr.instance(context);
133 attrRecover = AttrRecover.instance(context);
134 deferredAttr = DeferredAttr.instance(context);
135 chk = Check.instance(context);
136 infer = Infer.instance(context);
137 finder = ClassFinder.instance(context);
138 moduleFinder = ModuleFinder.instance(context);
139 types = Types.instance(context);
140 diags = JCDiagnostic.Factory.instance(context);
141 preview = Preview.instance(context);
142 Source source = Source.instance(context);
143 Options options = Options.instance(context);
144 compactMethodDiags = options.isSet(Option.XDIAGS, "compact") ||
145 options.isUnset(Option.XDIAGS) && options.isUnset("rawDiagnostics");
146 verboseResolutionMode = VerboseResolutionMode.getVerboseResolutionMode(options);
147 Target target = Target.instance(context);
148 allowLocalVariableTypeInference = Feature.LOCAL_VARIABLE_TYPE_INFERENCE.allowedInSource(source);
149 allowYieldStatement = Feature.SWITCH_EXPRESSION.allowedInSource(source);
150 polymorphicSignatureScope = WriteableScope.create(syms.noSymbol);
151 allowModules = Feature.MODULES.allowedInSource(source);
152 allowRecords = Feature.RECORDS.allowedInSource(source);
153 dumpMethodReferenceSearchResults = options.isSet("debug.dumpMethodReferenceSearchResults");
154 dumpStacktraceOnError = options.isSet("dev") || options.isSet(DOE);
155 }
156
157 /** error symbols, which are returned when resolution fails
158 */
159 private final SymbolNotFoundError varNotFound;
160 private final SymbolNotFoundError methodNotFound;
161 private final SymbolNotFoundError typeNotFound;
162
163 /** empty reference lookup result */
164 private final ReferenceLookupResult referenceNotFound;
165
166 public static Resolve instance(Context context) {
167 Resolve instance = context.get(resolveKey);
168 if (instance == null)
169 instance = new Resolve(context);
170 return instance;
171 }
172
173 private static Symbol bestOf(Symbol s1,
174 Symbol s2) {
175 return s1.kind.betterThan(s2.kind) ? s1 : s2;
176 }
177
178 // <editor-fold defaultstate="collapsed" desc="Verbose resolution diagnostics support">
179 enum VerboseResolutionMode {
180 SUCCESS("success"),
181 FAILURE("failure"),
182 APPLICABLE("applicable"),
183 INAPPLICABLE("inapplicable"),
184 DEFERRED_INST("deferred-inference"),
185 PREDEF("predef"),
186 OBJECT_INIT("object-init"),
187 INTERNAL("internal");
188
189 final String opt;
190
191 private VerboseResolutionMode(String opt) {
192 this.opt = opt;
193 }
194
195 static EnumSet<VerboseResolutionMode> getVerboseResolutionMode(Options opts) {
196 String s = opts.get("debug.verboseResolution");
197 EnumSet<VerboseResolutionMode> res = EnumSet.noneOf(VerboseResolutionMode.class);
198 if (s == null) return res;
199 if (s.contains("all")) {
200 res = EnumSet.allOf(VerboseResolutionMode.class);
201 }
202 Collection<String> args = Arrays.asList(s.split(","));
203 for (VerboseResolutionMode mode : values()) {
204 if (args.contains(mode.opt)) {
205 res.add(mode);
206 } else if (args.contains("-" + mode.opt)) {
207 res.remove(mode);
208 }
209 }
210 return res;
211 }
212 }
213
214 void reportVerboseResolutionDiagnostic(DiagnosticPosition dpos, Name name, Type site,
215 List<Type> argtypes, List<Type> typeargtypes, Symbol bestSoFar) {
216 boolean success = !bestSoFar.kind.isResolutionError();
217
218 if (success && !verboseResolutionMode.contains(VerboseResolutionMode.SUCCESS)) {
219 return;
220 } else if (!success && !verboseResolutionMode.contains(VerboseResolutionMode.FAILURE)) {
221 return;
222 }
223
224 if (bestSoFar.name == names.init &&
225 bestSoFar.owner == syms.objectType.tsym &&
226 !verboseResolutionMode.contains(VerboseResolutionMode.OBJECT_INIT)) {
227 return; //skip diags for Object constructor resolution
228 } else if (site == syms.predefClass.type &&
229 !verboseResolutionMode.contains(VerboseResolutionMode.PREDEF)) {
230 return; //skip spurious diags for predef symbols (i.e. operators)
231 } else if (currentResolutionContext.internalResolution &&
232 !verboseResolutionMode.contains(VerboseResolutionMode.INTERNAL)) {
233 return;
234 }
235
236 int pos = 0;
237 int mostSpecificPos = -1;
238 ListBuffer<JCDiagnostic> subDiags = new ListBuffer<>();
239 for (Candidate c : currentResolutionContext.candidates) {
240 if (currentResolutionContext.step != c.step ||
241 (c.isApplicable() && !verboseResolutionMode.contains(VerboseResolutionMode.APPLICABLE)) ||
242 (!c.isApplicable() && !verboseResolutionMode.contains(VerboseResolutionMode.INAPPLICABLE))) {
243 continue;
244 } else {
245 subDiags.append(c.isApplicable() ?
246 getVerboseApplicableCandidateDiag(pos, c.sym, c.mtype) :
247 getVerboseInapplicableCandidateDiag(pos, c.sym, c.details));
248 if (c.sym == bestSoFar)
249 mostSpecificPos = pos;
250 pos++;
251 }
252 }
253 String key = success ? "verbose.resolve.multi" : "verbose.resolve.multi.1";
254 List<Type> argtypes2 = argtypes.map(deferredAttr.new RecoveryDeferredTypeMap(AttrMode.SPECULATIVE, bestSoFar, currentResolutionContext.step));
255 JCDiagnostic main = diags.note(log.currentSource(), dpos, key, name,
256 site.tsym, mostSpecificPos, currentResolutionContext.step,
257 methodArguments(argtypes2),
258 methodArguments(typeargtypes));
259 JCDiagnostic d = new JCDiagnostic.MultilineDiagnostic(main, subDiags.toList());
260 log.report(d);
261 }
262
263 JCDiagnostic getVerboseApplicableCandidateDiag(int pos, Symbol sym, Type inst) {
264 JCDiagnostic subDiag = null;
265 if (sym.type.hasTag(FORALL)) {
266 subDiag = diags.fragment(Fragments.PartialInstSig(inst));
267 }
268
269 String key = subDiag == null ?
270 "applicable.method.found" :
271 "applicable.method.found.1";
272
273 return diags.fragment(key, pos, sym, subDiag);
274 }
275
276 JCDiagnostic getVerboseInapplicableCandidateDiag(int pos, Symbol sym, JCDiagnostic subDiag) {
277 return diags.fragment(Fragments.NotApplicableMethodFound(pos, sym, subDiag));
278 }
279 // </editor-fold>
280
281 /* ************************************************************************
282 * Identifier resolution
283 *************************************************************************/
284
285 /** An environment is "static" if its static level is greater than
286 * the one of its outer environment
287 */
288 protected static boolean isStatic(Env<AttrContext> env) {
289 return env.outer != null && env.info.staticLevel > env.outer.info.staticLevel;
290 }
291
292 /** An environment is an "initializer" if it is a constructor or
293 * an instance initializer.
294 */
295 static boolean isInitializer(Env<AttrContext> env) {
296 Symbol owner = env.info.scope.owner;
297 return owner.isConstructor() ||
298 owner.owner.kind == TYP &&
299 (owner.kind == VAR ||
300 owner.kind == MTH && (owner.flags() & BLOCK) != 0) &&
301 (owner.flags() & STATIC) == 0;
302 }
303
304 /** Is class accessible in given environment?
305 * @param env The current environment.
306 * @param c The class whose accessibility is checked.
307 */
308 public boolean isAccessible(Env<AttrContext> env, TypeSymbol c) {
309 return isAccessible(env, c, false);
310 }
311
312 public boolean isAccessible(Env<AttrContext> env, TypeSymbol c, boolean checkInner) {
313
314 /* 15.9.5.1: Note that it is possible for the signature of the anonymous constructor
315 to refer to an inaccessible type
316 */
317 if (env.enclMethod != null && (env.enclMethod.mods.flags & ANONCONSTR) != 0)
318 return true;
319
320 if (env.info.visitingServiceImplementation &&
321 env.toplevel.modle == c.packge().modle) {
322 return true;
323 }
324
325 boolean isAccessible = false;
326 switch ((short)(c.flags() & AccessFlags)) {
327 case PRIVATE:
328 isAccessible =
329 env.enclClass.sym.outermostClass() ==
330 c.owner.outermostClass();
331 break;
332 case 0:
333 isAccessible =
334 env.toplevel.packge == c.owner // fast special case
335 ||
336 env.toplevel.packge == c.packge();
337 break;
338 default: // error recovery
339 isAccessible = true;
340 break;
341 case PUBLIC:
342 if (allowModules) {
343 ModuleSymbol currModule = env.toplevel.modle;
344 currModule.complete();
345 PackageSymbol p = c.packge();
346 isAccessible =
347 currModule == p.modle ||
348 currModule.visiblePackages.get(p.fullname) == p ||
349 p == syms.rootPackage ||
350 (p.modle == syms.unnamedModule && currModule.readModules.contains(p.modle));
351 } else {
352 isAccessible = true;
353 }
354 break;
355 case PROTECTED:
356 isAccessible =
357 env.toplevel.packge == c.owner // fast special case
358 ||
359 env.toplevel.packge == c.packge()
360 ||
361 isInnerSubClass(env.enclClass.sym, c.owner)
362 ||
363 env.info.allowProtectedAccess;
364 break;
365 }
366 return (checkInner == false || c.type.getEnclosingType() == Type.noType) ?
367 isAccessible :
368 isAccessible && isAccessible(env, c.type.getEnclosingType(), checkInner);
369 }
370 //where
371 /** Is given class a subclass of given base class, or an inner class
372 * of a subclass?
373 * Return null if no such class exists.
374 * @param c The class which is the subclass or is contained in it.
375 * @param base The base class
376 */
377 private boolean isInnerSubClass(ClassSymbol c, Symbol base) {
378 while (c != null && !c.isSubClass(base, types)) {
379 c = c.owner.enclClass();
380 }
381 return c != null;
382 }
383
384 boolean isAccessible(Env<AttrContext> env, Type t) {
385 return isAccessible(env, t, false);
386 }
387
388 boolean isAccessible(Env<AttrContext> env, Type t, boolean checkInner) {
389 if (t.hasTag(ARRAY)) {
390 return isAccessible(env, types.cvarUpperBound(types.elemtype(t)));
391 } else if (t.isUnion()) {
392 return StreamSupport.stream(((UnionClassType) t).getAlternativeTypes().spliterator(), false)
393 .allMatch(alternative -> isAccessible(env, alternative.tsym, checkInner));
394 } else {
395 return isAccessible(env, t.tsym, checkInner);
396 }
397 }
398
399 /** Is symbol accessible as a member of given type in given environment?
400 * @param env The current environment.
401 * @param site The type of which the tested symbol is regarded
402 * as a member.
403 * @param sym The symbol.
404 */
405 public boolean isAccessible(Env<AttrContext> env, Type site, Symbol sym) {
406 return isAccessible(env, site, sym, false);
407 }
408 public boolean isAccessible(Env<AttrContext> env, Type site, Symbol sym, boolean checkInner) {
409 if (sym.name == names.init && sym.owner != site.tsym) return false;
410
411 /* 15.9.5.1: Note that it is possible for the signature of the anonymous constructor
412 to refer to an inaccessible type
413 */
414 if (env.enclMethod != null && (env.enclMethod.mods.flags & ANONCONSTR) != 0)
415 return true;
416
417 if (env.info.visitingServiceImplementation &&
418 env.toplevel.modle == sym.packge().modle) {
419 return true;
420 }
421
422 switch ((short)(sym.flags() & AccessFlags)) {
423 case PRIVATE:
424 return
425 (env.enclClass.sym == sym.owner // fast special case
426 ||
427 env.enclClass.sym.outermostClass() ==
428 sym.owner.outermostClass())
429 &&
430 sym.isInheritedIn(site.tsym, types);
431 case 0:
432 return
433 (env.toplevel.packge == sym.owner.owner // fast special case
434 ||
435 env.toplevel.packge == sym.packge())
436 &&
437 isAccessible(env, site, checkInner)
438 &&
439 sym.isInheritedIn(site.tsym, types)
440 &&
441 notOverriddenIn(site, sym);
442 case PROTECTED:
443 return
444 (env.toplevel.packge == sym.owner.owner // fast special case
445 ||
446 env.toplevel.packge == sym.packge()
447 ||
448 isProtectedAccessible(sym, env.enclClass.sym, site)
449 ||
450 // OK to select instance method or field from 'super' or type name
451 // (but type names should be disallowed elsewhere!)
452 env.info.selectSuper && (sym.flags() & STATIC) == 0 && sym.kind != TYP)
453 &&
454 isAccessible(env, site, checkInner)
455 &&
456 notOverriddenIn(site, sym);
457 default: // this case includes erroneous combinations as well
458 return isAccessible(env, site, checkInner) && notOverriddenIn(site, sym);
459 }
460 }
461 //where
462 /* `sym' is accessible only if not overridden by
463 * another symbol which is a member of `site'
464 * (because, if it is overridden, `sym' is not strictly
465 * speaking a member of `site'). A polymorphic signature method
466 * cannot be overridden (e.g. MH.invokeExact(Object[])).
467 */
468 private boolean notOverriddenIn(Type site, Symbol sym) {
469 if (sym.kind != MTH || sym.isConstructor() || sym.isStatic())
470 return true;
471 else {
472 Symbol s2 = ((MethodSymbol)sym).implementation(site.tsym, types, true);
473 return (s2 == null || s2 == sym || sym.owner == s2.owner || (sym.owner.isInterface() && s2.owner == syms.objectType.tsym) ||
474 !types.isSubSignature(types.memberType(site, s2), types.memberType(site, sym)));
475 }
476 }
477 //where
478 /** Is given protected symbol accessible if it is selected from given site
479 * and the selection takes place in given class?
480 * @param sym The symbol with protected access
481 * @param c The class where the access takes place
482 * @param site The type of the qualifier
483 */
484 private
485 boolean isProtectedAccessible(Symbol sym, ClassSymbol c, Type site) {
486 Type newSite = site.hasTag(TYPEVAR) ? site.getUpperBound() : site;
487 while (c != null &&
488 !(c.isSubClass(sym.owner, types) &&
489 (c.flags() & INTERFACE) == 0 &&
490 // In JLS 2e 6.6.2.1, the subclass restriction applies
491 // only to instance fields and methods -- types are excluded
492 // regardless of whether they are declared 'static' or not.
493 ((sym.flags() & STATIC) != 0 || sym.kind == TYP || newSite.tsym.isSubClass(c, types))))
494 c = c.owner.enclClass();
495 return c != null;
496 }
497
498 /**
499 * Performs a recursive scan of a type looking for accessibility problems
500 * from current attribution environment
501 */
502 void checkAccessibleType(Env<AttrContext> env, Type t) {
503 accessibilityChecker.visit(t, env);
504 }
505
506 /**
507 * Accessibility type-visitor
508 */
509 Types.SimpleVisitor<Void, Env<AttrContext>> accessibilityChecker =
510 new Types.SimpleVisitor<Void, Env<AttrContext>>() {
511
512 void visit(List<Type> ts, Env<AttrContext> env) {
513 for (Type t : ts) {
514 visit(t, env);
515 }
516 }
517
518 public Void visitType(Type t, Env<AttrContext> env) {
519 return null;
520 }
521
522 @Override
523 public Void visitArrayType(ArrayType t, Env<AttrContext> env) {
524 visit(t.elemtype, env);
525 return null;
526 }
527
528 @Override
529 public Void visitClassType(ClassType t, Env<AttrContext> env) {
530 visit(t.getTypeArguments(), env);
531 if (!isAccessible(env, t, true)) {
532 accessBase(new AccessError(env, null, t.tsym), env.tree.pos(), env.enclClass.sym, t, t.tsym.name, true);
533 }
534 return null;
535 }
536
537 @Override
538 public Void visitWildcardType(WildcardType t, Env<AttrContext> env) {
539 visit(t.type, env);
540 return null;
541 }
542
543 @Override
544 public Void visitMethodType(MethodType t, Env<AttrContext> env) {
545 visit(t.getParameterTypes(), env);
546 visit(t.getReturnType(), env);
547 visit(t.getThrownTypes(), env);
548 return null;
549 }
550 };
551
552 /** Try to instantiate the type of a method so that it fits
553 * given type arguments and argument types. If successful, return
554 * the method's instantiated type, else return null.
555 * The instantiation will take into account an additional leading
556 * formal parameter if the method is an instance method seen as a member
557 * of an under determined site. In this case, we treat site as an additional
558 * parameter and the parameters of the class containing the method as
559 * additional type variables that get instantiated.
560 *
561 * @param env The current environment
562 * @param site The type of which the method is a member.
563 * @param m The method symbol.
564 * @param argtypes The invocation's given value arguments.
565 * @param typeargtypes The invocation's given type arguments.
566 * @param allowBoxing Allow boxing conversions of arguments.
567 * @param useVarargs Box trailing arguments into an array for varargs.
568 */
569 Type rawInstantiate(Env<AttrContext> env,
570 Type site,
571 Symbol m,
572 ResultInfo resultInfo,
573 List<Type> argtypes,
574 List<Type> typeargtypes,
575 boolean allowBoxing,
576 boolean useVarargs,
577 Warner warn) throws Infer.InferenceException {
578 Type mt = types.memberType(site, m);
579 // tvars is the list of formal type variables for which type arguments
580 // need to inferred.
581 List<Type> tvars = List.nil();
582 if (typeargtypes == null) typeargtypes = List.nil();
583 if (!mt.hasTag(FORALL) && typeargtypes.nonEmpty()) {
584 // This is not a polymorphic method, but typeargs are supplied
585 // which is fine, see JLS 15.12.2.1
586 } else if (mt.hasTag(FORALL) && typeargtypes.nonEmpty()) {
587 ForAll pmt = (ForAll) mt;
588 if (typeargtypes.length() != pmt.tvars.length())
589 // not enough args
590 throw new InapplicableMethodException(diags.fragment(Fragments.WrongNumberTypeArgs(Integer.toString(pmt.tvars.length()))), dumpStacktraceOnError);
591 // Check type arguments are within bounds
592 List<Type> formals = pmt.tvars;
593 List<Type> actuals = typeargtypes;
594 while (formals.nonEmpty() && actuals.nonEmpty()) {
595 List<Type> bounds = types.subst(types.getBounds((TypeVar)formals.head),
596 pmt.tvars, typeargtypes);
597 for (; bounds.nonEmpty(); bounds = bounds.tail) {
598 if (!types.isSubtypeUnchecked(actuals.head, bounds.head, warn)) {
599 throw new InapplicableMethodException(diags.fragment(Fragments.ExplicitParamDoNotConformToBounds(actuals.head, bounds)), dumpStacktraceOnError);
600 }
601 }
602 formals = formals.tail;
603 actuals = actuals.tail;
604 }
605 mt = types.subst(pmt.qtype, pmt.tvars, typeargtypes);
606 } else if (mt.hasTag(FORALL)) {
607 ForAll pmt = (ForAll) mt;
608 List<Type> tvars1 = types.newInstances(pmt.tvars);
609 tvars = tvars.appendList(tvars1);
610 mt = types.subst(pmt.qtype, pmt.tvars, tvars1);
611 }
612
613 // find out whether we need to go the slow route via infer
614 boolean instNeeded = tvars.tail != null; /*inlined: tvars.nonEmpty()*/
615 for (List<Type> l = argtypes;
616 l.tail != null/*inlined: l.nonEmpty()*/ && !instNeeded;
617 l = l.tail) {
618 if (l.head.hasTag(FORALL)) instNeeded = true;
619 }
620
621 if (instNeeded) {
622 return infer.instantiateMethod(env,
623 tvars,
624 (MethodType)mt,
625 resultInfo,
626 (MethodSymbol)m,
627 argtypes,
628 allowBoxing,
629 useVarargs,
630 currentResolutionContext,
631 warn);
632 }
633
634 DeferredAttr.DeferredAttrContext dc = currentResolutionContext.deferredAttrContext(m, infer.emptyContext, resultInfo, warn);
635 currentResolutionContext.methodCheck.argumentsAcceptable(env, dc,
636 argtypes, mt.getParameterTypes(), warn);
637 dc.complete();
638 return mt;
639 }
640
641 Type checkMethod(Env<AttrContext> env,
642 Type site,
643 Symbol m,
644 ResultInfo resultInfo,
645 List<Type> argtypes,
646 List<Type> typeargtypes,
647 Warner warn) {
648 MethodResolutionContext prevContext = currentResolutionContext;
649 try {
650 currentResolutionContext = new MethodResolutionContext();
651 currentResolutionContext.attrMode = (resultInfo.pt == Infer.anyPoly) ?
652 AttrMode.SPECULATIVE : DeferredAttr.AttrMode.CHECK;
653 if (env.tree.hasTag(JCTree.Tag.REFERENCE)) {
654 //method/constructor references need special check class
655 //to handle inference variables in 'argtypes' (might happen
656 //during an unsticking round)
657 currentResolutionContext.methodCheck =
658 new MethodReferenceCheck(resultInfo.checkContext.inferenceContext());
659 }
660 MethodResolutionPhase step = currentResolutionContext.step = env.info.pendingResolutionPhase;
661 return rawInstantiate(env, site, m, resultInfo, argtypes, typeargtypes,
662 step.isBoxingRequired(), step.isVarargsRequired(), warn);
663 }
664 finally {
665 currentResolutionContext = prevContext;
666 }
667 }
668
669 /** Same but returns null instead throwing a NoInstanceException
670 */
671 Type instantiate(Env<AttrContext> env,
672 Type site,
673 Symbol m,
674 ResultInfo resultInfo,
675 List<Type> argtypes,
676 List<Type> typeargtypes,
677 boolean allowBoxing,
678 boolean useVarargs,
679 Warner warn) {
680 try {
681 return rawInstantiate(env, site, m, resultInfo, argtypes, typeargtypes,
682 allowBoxing, useVarargs, warn);
683 } catch (InapplicableMethodException ex) {
684 return null;
685 }
686 }
687
688 /**
689 * This interface defines an entry point that should be used to perform a
690 * method check. A method check usually consist in determining as to whether
691 * a set of types (actuals) is compatible with another set of types (formals).
692 * Since the notion of compatibility can vary depending on the circumstances,
693 * this interfaces allows to easily add new pluggable method check routines.
694 */
695 interface MethodCheck {
696 /**
697 * Main method check routine. A method check usually consist in determining
698 * as to whether a set of types (actuals) is compatible with another set of
699 * types (formals). If an incompatibility is found, an unchecked exception
700 * is assumed to be thrown.
701 */
702 void argumentsAcceptable(Env<AttrContext> env,
703 DeferredAttrContext deferredAttrContext,
704 List<Type> argtypes,
705 List<Type> formals,
706 Warner warn);
707
708 /**
709 * Retrieve the method check object that will be used during a
710 * most specific check.
711 */
712 MethodCheck mostSpecificCheck(List<Type> actuals);
713 }
714
715 /**
716 * Helper enum defining all method check diagnostics (used by resolveMethodCheck).
717 */
718 enum MethodCheckDiag {
719 /**
720 * Actuals and formals differs in length.
721 */
722 ARITY_MISMATCH("arg.length.mismatch", "infer.arg.length.mismatch"),
723 /**
724 * An actual is incompatible with a formal.
725 */
726 ARG_MISMATCH("no.conforming.assignment.exists", "infer.no.conforming.assignment.exists"),
727 /**
728 * An actual is incompatible with the varargs element type.
729 */
730 VARARG_MISMATCH("varargs.argument.mismatch", "infer.varargs.argument.mismatch"),
731 /**
732 * The varargs element type is inaccessible.
733 */
734 INACCESSIBLE_VARARGS("inaccessible.varargs.type", "inaccessible.varargs.type");
735
736 final String basicKey;
737 final String inferKey;
738
739 MethodCheckDiag(String basicKey, String inferKey) {
740 this.basicKey = basicKey;
741 this.inferKey = inferKey;
742 }
743
744 String regex() {
745 return String.format("([a-z]*\\.)*(%s|%s)", basicKey, inferKey);
746 }
747 }
748
749 /**
750 * Dummy method check object. All methods are deemed applicable, regardless
751 * of their formal parameter types.
752 */
753 MethodCheck nilMethodCheck = new MethodCheck() {
754 public void argumentsAcceptable(Env<AttrContext> env, DeferredAttrContext deferredAttrContext, List<Type> argtypes, List<Type> formals, Warner warn) {
755 //do nothing - method always applicable regardless of actuals
756 }
757
758 public MethodCheck mostSpecificCheck(List<Type> actuals) {
759 return this;
760 }
761 };
762
763 /**
764 * Base class for 'real' method checks. The class defines the logic for
765 * iterating through formals and actuals and provides and entry point
766 * that can be used by subclasses in order to define the actual check logic.
767 */
768 abstract class AbstractMethodCheck implements MethodCheck {
769 @Override
770 public void argumentsAcceptable(final Env<AttrContext> env,
771 DeferredAttrContext deferredAttrContext,
772 List<Type> argtypes,
773 List<Type> formals,
774 Warner warn) {
775 //should we expand formals?
776 boolean useVarargs = deferredAttrContext.phase.isVarargsRequired();
777 JCTree callTree = treeForDiagnostics(env);
778 List<JCExpression> trees = TreeInfo.args(callTree);
779
780 //inference context used during this method check
781 InferenceContext inferenceContext = deferredAttrContext.inferenceContext;
782
783 Type varargsFormal = useVarargs ? formals.last() : null;
784
785 if (varargsFormal == null &&
786 argtypes.size() != formals.size()) {
787 reportMC(callTree, MethodCheckDiag.ARITY_MISMATCH, inferenceContext); // not enough args
788 }
789
790 while (argtypes.nonEmpty() && formals.head != varargsFormal) {
791 DiagnosticPosition pos = trees != null ? trees.head : null;
792 checkArg(pos, false, argtypes.head, formals.head, deferredAttrContext, warn);
793 argtypes = argtypes.tail;
794 formals = formals.tail;
795 trees = trees != null ? trees.tail : trees;
796 }
797
798 if (formals.head != varargsFormal) {
799 reportMC(callTree, MethodCheckDiag.ARITY_MISMATCH, inferenceContext); // not enough args
800 }
801
802 if (useVarargs) {
803 //note: if applicability check is triggered by most specific test,
804 //the last argument of a varargs is _not_ an array type (see JLS 15.12.2.5)
805 final Type elt = types.elemtype(varargsFormal);
806 while (argtypes.nonEmpty()) {
807 DiagnosticPosition pos = trees != null ? trees.head : null;
808 checkArg(pos, true, argtypes.head, elt, deferredAttrContext, warn);
809 argtypes = argtypes.tail;
810 trees = trees != null ? trees.tail : trees;
811 }
812 }
813 }
814
815 // where
816 private JCTree treeForDiagnostics(Env<AttrContext> env) {
817 return env.info.preferredTreeForDiagnostics != null ? env.info.preferredTreeForDiagnostics : env.tree;
818 }
819
820 /**
821 * Does the actual argument conforms to the corresponding formal?
822 */
823 abstract void checkArg(DiagnosticPosition pos, boolean varargs, Type actual, Type formal, DeferredAttrContext deferredAttrContext, Warner warn);
824
825 protected void reportMC(DiagnosticPosition pos, MethodCheckDiag diag, InferenceContext inferenceContext, Object... args) {
826 boolean inferDiag = inferenceContext != infer.emptyContext;
827 if (inferDiag && (!diag.inferKey.equals(diag.basicKey))) {
828 Object[] args2 = new Object[args.length + 1];
829 System.arraycopy(args, 0, args2, 1, args.length);
830 args2[0] = inferenceContext.inferenceVars();
831 args = args2;
832 }
833 String key = inferDiag ? diag.inferKey : diag.basicKey;
834 throw inferDiag ?
835 infer.error(diags.create(DiagnosticType.FRAGMENT, log.currentSource(), pos, key, args)) :
836 getMethodCheckFailure().setMessage(diags.create(DiagnosticType.FRAGMENT, log.currentSource(), pos, key, args));
837 }
838
839 /**
840 * To eliminate the overhead associated with allocating an exception object in such an
841 * hot execution path, we use flyweight pattern - and share the same exception instance
842 * across multiple method check failures.
843 */
844 class SharedInapplicableMethodException extends InapplicableMethodException {
845 private static final long serialVersionUID = 0;
846
847 SharedInapplicableMethodException() {
848 super(null, Resolve.this.dumpStacktraceOnError);
849 }
850
851 SharedInapplicableMethodException setMessage(JCDiagnostic details) {
852 this.diagnostic = details;
853 return this;
854 }
855 }
856
857 private SharedInapplicableMethodException methodCheckFailure;
858
859 public MethodCheck mostSpecificCheck(List<Type> actuals) {
860 return nilMethodCheck;
861 }
862
863 private SharedInapplicableMethodException getMethodCheckFailure() {
864 return methodCheckFailure == null ? methodCheckFailure = new SharedInapplicableMethodException() : methodCheckFailure;
865 }
866 }
867
868 /**
869 * Arity-based method check. A method is applicable if the number of actuals
870 * supplied conforms to the method signature.
871 */
872 MethodCheck arityMethodCheck = new AbstractMethodCheck() {
873 @Override
874 void checkArg(DiagnosticPosition pos, boolean varargs, Type actual, Type formal, DeferredAttrContext deferredAttrContext, Warner warn) {
875 //do nothing - actual always compatible to formals
876 }
877
878 @Override
879 public String toString() {
880 return "arityMethodCheck";
881 }
882 };
883
884 /**
885 * Main method applicability routine. Given a list of actual types A,
886 * a list of formal types F, determines whether the types in A are
887 * compatible (by method invocation conversion) with the types in F.
888 *
889 * Since this routine is shared between overload resolution and method
890 * type-inference, a (possibly empty) inference context is used to convert
891 * formal types to the corresponding 'undet' form ahead of a compatibility
892 * check so that constraints can be propagated and collected.
893 *
894 * Moreover, if one or more types in A is a deferred type, this routine uses
895 * DeferredAttr in order to perform deferred attribution. If one or more actual
896 * deferred types are stuck, they are placed in a queue and revisited later
897 * after the remainder of the arguments have been seen. If this is not sufficient
898 * to 'unstuck' the argument, a cyclic inference error is called out.
899 *
900 * A method check handler (see above) is used in order to report errors.
901 */
902 MethodCheck resolveMethodCheck = new AbstractMethodCheck() {
903
904 @Override
905 void checkArg(DiagnosticPosition pos, boolean varargs, Type actual, Type formal, DeferredAttrContext deferredAttrContext, Warner warn) {
906 ResultInfo mresult = methodCheckResult(varargs, formal, deferredAttrContext, warn);
907 mresult.check(pos, actual);
908 }
909
910 @Override
911 public void argumentsAcceptable(final Env<AttrContext> env,
912 DeferredAttrContext deferredAttrContext,
913 List<Type> argtypes,
914 List<Type> formals,
915 Warner warn) {
916 super.argumentsAcceptable(env, deferredAttrContext, argtypes, formals, warn);
917 // should we check varargs element type accessibility?
918 if (deferredAttrContext.phase.isVarargsRequired()) {
919 if (deferredAttrContext.mode == AttrMode.CHECK) {
920 varargsAccessible(env, types.elemtype(formals.last()), deferredAttrContext.inferenceContext);
921 }
922 }
923 }
924
925 /**
926 * Test that the runtime array element type corresponding to 't' is accessible. 't' should be the
927 * varargs element type of either the method invocation type signature (after inference completes)
928 * or the method declaration signature (before inference completes).
929 */
930 private void varargsAccessible(final Env<AttrContext> env, final Type t, final InferenceContext inferenceContext) {
931 if (inferenceContext.free(t)) {
932 inferenceContext.addFreeTypeListener(List.of(t),
933 solvedContext -> varargsAccessible(env, solvedContext.asInstType(t), solvedContext));
934 } else {
935 if (!isAccessible(env, types.erasure(t))) {
936 Symbol location = env.enclClass.sym;
937 reportMC(env.tree, MethodCheckDiag.INACCESSIBLE_VARARGS, inferenceContext, t, Kinds.kindName(location), location);
938 }
939 }
940 }
941
942 private ResultInfo methodCheckResult(final boolean varargsCheck, Type to,
943 final DeferredAttr.DeferredAttrContext deferredAttrContext, Warner rsWarner) {
944 CheckContext checkContext = new MethodCheckContext(!deferredAttrContext.phase.isBoxingRequired(), deferredAttrContext, rsWarner) {
945 MethodCheckDiag methodDiag = varargsCheck ?
946 MethodCheckDiag.VARARG_MISMATCH : MethodCheckDiag.ARG_MISMATCH;
947
948 @Override
949 public void report(DiagnosticPosition pos, JCDiagnostic details) {
950 reportMC(pos, methodDiag, deferredAttrContext.inferenceContext, details);
951 }
952 };
953 return new MethodResultInfo(to, checkContext);
954 }
955
956 @Override
957 public MethodCheck mostSpecificCheck(List<Type> actuals) {
958 return new MostSpecificCheck(actuals);
959 }
960
961 @Override
962 public String toString() {
963 return "resolveMethodCheck";
964 }
965 };
966
967 /**
968 * This class handles method reference applicability checks; since during
969 * these checks it's sometime possible to have inference variables on
970 * the actual argument types list, the method applicability check must be
971 * extended so that inference variables are 'opened' as needed.
972 */
973 class MethodReferenceCheck extends AbstractMethodCheck {
974
975 InferenceContext pendingInferenceContext;
976
977 MethodReferenceCheck(InferenceContext pendingInferenceContext) {
978 this.pendingInferenceContext = pendingInferenceContext;
979 }
980
981 @Override
982 void checkArg(DiagnosticPosition pos, boolean varargs, Type actual, Type formal, DeferredAttrContext deferredAttrContext, Warner warn) {
983 ResultInfo mresult = methodCheckResult(varargs, formal, deferredAttrContext, warn);
984 mresult.check(pos, actual);
985 }
986
987 private ResultInfo methodCheckResult(final boolean varargsCheck, Type to,
988 final DeferredAttr.DeferredAttrContext deferredAttrContext, Warner rsWarner) {
989 CheckContext checkContext = new MethodCheckContext(!deferredAttrContext.phase.isBoxingRequired(), deferredAttrContext, rsWarner) {
990 MethodCheckDiag methodDiag = varargsCheck ?
991 MethodCheckDiag.VARARG_MISMATCH : MethodCheckDiag.ARG_MISMATCH;
992
993 @Override
994 public boolean compatible(Type found, Type req, Warner warn) {
995 found = pendingInferenceContext.asUndetVar(found);
996 if (found.hasTag(UNDETVAR) && req.isPrimitive()) {
997 req = types.boxedClass(req).type;
998 }
999 return super.compatible(found, req, warn);
1000 }
1001
1002 @Override
1003 public void report(DiagnosticPosition pos, JCDiagnostic details) {
1004 reportMC(pos, methodDiag, deferredAttrContext.inferenceContext, details);
1005 }
1006 };
1007 return new MethodResultInfo(to, checkContext);
1008 }
1009
1010 @Override
1011 public MethodCheck mostSpecificCheck(List<Type> actuals) {
1012 return new MostSpecificCheck(actuals);
1013 }
1014
1015 @Override
1016 public String toString() {
1017 return "MethodReferenceCheck";
1018 }
1019 }
1020
1021 /**
1022 * Check context to be used during method applicability checks. A method check
1023 * context might contain inference variables.
1024 */
1025 abstract class MethodCheckContext implements CheckContext {
1026
1027 boolean strict;
1028 DeferredAttrContext deferredAttrContext;
1029 Warner rsWarner;
1030
1031 public MethodCheckContext(boolean strict, DeferredAttrContext deferredAttrContext, Warner rsWarner) {
1032 this.strict = strict;
1033 this.deferredAttrContext = deferredAttrContext;
1034 this.rsWarner = rsWarner;
1035 }
1036
1037 public boolean compatible(Type found, Type req, Warner warn) {
1038 InferenceContext inferenceContext = deferredAttrContext.inferenceContext;
1039 return strict ?
1040 types.isSubtypeUnchecked(inferenceContext.asUndetVar(found), inferenceContext.asUndetVar(req), warn) :
1041 types.isConvertible(inferenceContext.asUndetVar(found), inferenceContext.asUndetVar(req), warn);
1042 }
1043
1044 public void report(DiagnosticPosition pos, JCDiagnostic details) {
1045 throw new InapplicableMethodException(details, Resolve.this.dumpStacktraceOnError);
1046 }
1047
1048 public Warner checkWarner(DiagnosticPosition pos, Type found, Type req) {
1049 return rsWarner;
1050 }
1051
1052 public InferenceContext inferenceContext() {
1053 return deferredAttrContext.inferenceContext;
1054 }
1055
1056 public DeferredAttrContext deferredAttrContext() {
1057 return deferredAttrContext;
1058 }
1059
1060 @Override
1061 public String toString() {
1062 return "MethodCheckContext";
1063 }
1064 }
1065
1066 /**
1067 * ResultInfo class to be used during method applicability checks. Check
1068 * for deferred types goes through special path.
1069 */
1070 class MethodResultInfo extends ResultInfo {
1071
1072 public MethodResultInfo(Type pt, CheckContext checkContext) {
1073 attr.super(KindSelector.VAL, pt, checkContext);
1074 }
1075
1076 @Override
1077 protected Type check(DiagnosticPosition pos, Type found) {
1078 if (found.hasTag(DEFERRED)) {
1079 DeferredType dt = (DeferredType)found;
1080 return dt.check(this);
1081 } else {
1082 Type uResult = U(found);
1083 Type capturedType = pos == null || pos.getTree() == null ?
1084 types.capture(uResult) :
1085 checkContext.inferenceContext()
1086 .cachedCapture(pos.getTree(), uResult, true);
1087 return super.check(pos, chk.checkNonVoid(pos, capturedType));
1088 }
1089 }
1090
1091 /**
1092 * javac has a long-standing 'simplification' (see 6391995):
1093 * given an actual argument type, the method check is performed
1094 * on its upper bound. This leads to inconsistencies when an
1095 * argument type is checked against itself. For example, given
1096 * a type-variable T, it is not true that {@code U(T) <: T},
1097 * so we need to guard against that.
1098 */
1099 private Type U(Type found) {
1100 return found == pt ?
1101 found : types.cvarUpperBound(found);
1102 }
1103
1104 @Override
1105 protected MethodResultInfo dup(Type newPt) {
1106 return new MethodResultInfo(newPt, checkContext);
1107 }
1108
1109 @Override
1110 protected ResultInfo dup(CheckContext newContext) {
1111 return new MethodResultInfo(pt, newContext);
1112 }
1113
1114 @Override
1115 protected ResultInfo dup(Type newPt, CheckContext newContext) {
1116 return new MethodResultInfo(newPt, newContext);
1117 }
1118 }
1119
1120 /**
1121 * Most specific method applicability routine. Given a list of actual types A,
1122 * a list of formal types F1, and a list of formal types F2, the routine determines
1123 * as to whether the types in F1 can be considered more specific than those in F2 w.r.t.
1124 * argument types A.
1125 */
1126 class MostSpecificCheck implements MethodCheck {
1127
1128 List<Type> actuals;
1129
1130 MostSpecificCheck(List<Type> actuals) {
1131 this.actuals = actuals;
1132 }
1133
1134 @Override
1135 public void argumentsAcceptable(final Env<AttrContext> env,
1136 DeferredAttrContext deferredAttrContext,
1137 List<Type> formals1,
1138 List<Type> formals2,
1139 Warner warn) {
1140 formals2 = adjustArgs(formals2, deferredAttrContext.msym, formals1.length(), deferredAttrContext.phase.isVarargsRequired());
1141 while (formals2.nonEmpty()) {
1142 ResultInfo mresult = methodCheckResult(formals2.head, deferredAttrContext, warn, actuals.head);
1143 mresult.check(null, formals1.head);
1144 formals1 = formals1.tail;
1145 formals2 = formals2.tail;
1146 actuals = actuals.isEmpty() ? actuals : actuals.tail;
1147 }
1148 }
1149
1150 /**
1151 * Create a method check context to be used during the most specific applicability check
1152 */
1153 ResultInfo methodCheckResult(Type to, DeferredAttr.DeferredAttrContext deferredAttrContext,
1154 Warner rsWarner, Type actual) {
1155 return attr.new ResultInfo(KindSelector.VAL, to,
1156 new MostSpecificCheckContext(deferredAttrContext, rsWarner, actual));
1157 }
1158
1159 /**
1160 * Subclass of method check context class that implements most specific
1161 * method conversion. If the actual type under analysis is a deferred type
1162 * a full blown structural analysis is carried out.
1163 */
1164 class MostSpecificCheckContext extends MethodCheckContext {
1165
1166 Type actual;
1167
1168 public MostSpecificCheckContext(DeferredAttrContext deferredAttrContext, Warner rsWarner, Type actual) {
1169 super(true, deferredAttrContext, rsWarner);
1170 this.actual = actual;
1171 }
1172
1173 public boolean compatible(Type found, Type req, Warner warn) {
1174 if (unrelatedFunctionalInterfaces(found, req) &&
1175 (actual != null && actual.getTag() == DEFERRED)) {
1176 DeferredType dt = (DeferredType) actual;
1177 JCTree speculativeTree = dt.speculativeTree(deferredAttrContext);
1178 if (speculativeTree != deferredAttr.stuckTree) {
1179 return functionalInterfaceMostSpecific(found, req, speculativeTree);
1180 }
1181 }
1182 return compatibleBySubtyping(found, req);
1183 }
1184
1185 private boolean compatibleBySubtyping(Type found, Type req) {
1186 if (!strict && found.isPrimitive() != req.isPrimitive()) {
1187 found = found.isPrimitive() ? types.boxedClass(found).type : types.unboxedType(found);
1188 }
1189 return types.isSubtypeNoCapture(found, deferredAttrContext.inferenceContext.asUndetVar(req));
1190 }
1191
1192 /** Whether {@code t} and {@code s} are unrelated functional interface types. */
1193 private boolean unrelatedFunctionalInterfaces(Type t, Type s) {
1194 return types.isFunctionalInterface(t.tsym) &&
1195 types.isFunctionalInterface(s.tsym) &&
1196 unrelatedInterfaces(t, s);
1197 }
1198
1199 /** Whether {@code t} and {@code s} are unrelated interface types; recurs on intersections. **/
1200 private boolean unrelatedInterfaces(Type t, Type s) {
1201 if (t.isCompound()) {
1202 for (Type ti : types.interfaces(t)) {
1203 if (!unrelatedInterfaces(ti, s)) {
1204 return false;
1205 }
1206 }
1207 return true;
1208 } else if (s.isCompound()) {
1209 for (Type si : types.interfaces(s)) {
1210 if (!unrelatedInterfaces(t, si)) {
1211 return false;
1212 }
1213 }
1214 return true;
1215 } else {
1216 return types.asSuper(t, s.tsym) == null && types.asSuper(s, t.tsym) == null;
1217 }
1218 }
1219
1220 /** Parameters {@code t} and {@code s} are unrelated functional interface types. */
1221 private boolean functionalInterfaceMostSpecific(Type t, Type s, JCTree tree) {
1222 Type tDesc;
1223 Type tDescNoCapture;
1224 Type sDesc;
1225 try {
1226 tDesc = types.findDescriptorType(types.capture(t));
1227 tDescNoCapture = types.findDescriptorType(t);
1228 sDesc = types.findDescriptorType(s);
1229 } catch (Types.FunctionDescriptorLookupError ex) {
1230 // don't report, a more meaningful error should be reported upstream
1231 return false;
1232 }
1233 final List<Type> tTypeParams = tDesc.getTypeArguments();
1234 final List<Type> tTypeParamsNoCapture = tDescNoCapture.getTypeArguments();
1235 final List<Type> sTypeParams = sDesc.getTypeArguments();
1236
1237 // compare type parameters
1238 if (tDesc.hasTag(FORALL) && !types.hasSameBounds((ForAll) tDesc, (ForAll) tDescNoCapture)) {
1239 return false;
1240 }
1241 // can't use Types.hasSameBounds on sDesc because bounds may have ivars
1242 List<Type> tIter = tTypeParams;
1243 List<Type> sIter = sTypeParams;
1244 while (tIter.nonEmpty() && sIter.nonEmpty()) {
1245 Type tBound = tIter.head.getUpperBound();
1246 Type sBound = types.subst(sIter.head.getUpperBound(), sTypeParams, tTypeParams);
1247 if (tBound.containsAny(tTypeParams) && inferenceContext().free(sBound)) {
1248 return false;
1249 }
1250 if (!types.isSameType(tBound, inferenceContext().asUndetVar(sBound))) {
1251 return false;
1252 }
1253 tIter = tIter.tail;
1254 sIter = sIter.tail;
1255 }
1256 if (!tIter.isEmpty() || !sIter.isEmpty()) {
1257 return false;
1258 }
1259
1260 // compare parameters
1261 List<Type> tParams = tDesc.getParameterTypes();
1262 List<Type> tParamsNoCapture = tDescNoCapture.getParameterTypes();
1263 List<Type> sParams = sDesc.getParameterTypes();
1264 while (tParams.nonEmpty() && tParamsNoCapture.nonEmpty() && sParams.nonEmpty()) {
1265 Type tParam = tParams.head;
1266 Type tParamNoCapture = types.subst(tParamsNoCapture.head, tTypeParamsNoCapture, tTypeParams);
1267 Type sParam = types.subst(sParams.head, sTypeParams, tTypeParams);
1268 if (tParam.containsAny(tTypeParams) && inferenceContext().free(sParam)) {
1269 return false;
1270 }
1271 if (!types.isSubtype(inferenceContext().asUndetVar(sParam), tParam)) {
1272 return false;
1273 }
1274 if (!types.isSameType(tParamNoCapture, inferenceContext().asUndetVar(sParam))) {
1275 return false;
1276 }
1277 tParams = tParams.tail;
1278 tParamsNoCapture = tParamsNoCapture.tail;
1279 sParams = sParams.tail;
1280 }
1281 if (!tParams.isEmpty() || !tParamsNoCapture.isEmpty() || !sParams.isEmpty()) {
1282 return false;
1283 }
1284
1285 // compare returns
1286 Type tRet = tDesc.getReturnType();
1287 Type sRet = types.subst(sDesc.getReturnType(), sTypeParams, tTypeParams);
1288 if (tRet.containsAny(tTypeParams) && inferenceContext().free(sRet)) {
1289 return false;
1290 }
1291 MostSpecificFunctionReturnChecker msc = new MostSpecificFunctionReturnChecker(tRet, sRet);
1292 msc.scan(tree);
1293 return msc.result;
1294 }
1295
1296 /**
1297 * Tests whether one functional interface type can be considered more specific
1298 * than another unrelated functional interface type for the scanned expression.
1299 */
1300 class MostSpecificFunctionReturnChecker extends DeferredAttr.PolyScanner {
1301
1302 final Type tRet;
1303 final Type sRet;
1304 boolean result;
1305
1306 /** Parameters {@code t} and {@code s} are unrelated functional interface types. */
1307 MostSpecificFunctionReturnChecker(Type tRet, Type sRet) {
1308 this.tRet = tRet;
1309 this.sRet = sRet;
1310 result = true;
1311 }
1312
1313 @Override
1314 void skip(JCTree tree) {
1315 result = false;
1316 }
1317
1318 @Override
1319 public void visitConditional(JCConditional tree) {
1320 scan(asExpr(tree.truepart));
1321 scan(asExpr(tree.falsepart));
1322 }
1323
1324 @Override
1325 public void visitReference(JCMemberReference tree) {
1326 if (sRet.hasTag(VOID)) {
1327 // do nothing
1328 } else if (tRet.hasTag(VOID)) {
1329 result = false;
1330 } else if (tRet.isPrimitive() != sRet.isPrimitive()) {
1331 boolean retValIsPrimitive =
1332 tree.refPolyKind == PolyKind.STANDALONE &&
1333 tree.sym.type.getReturnType().isPrimitive();
1334 result &= (retValIsPrimitive == tRet.isPrimitive()) &&
1335 (retValIsPrimitive != sRet.isPrimitive());
1336 } else {
1337 result &= compatibleBySubtyping(tRet, sRet);
1338 }
1339 }
1340
1341 @Override
1342 public void visitParens(JCParens tree) {
1343 scan(asExpr(tree.expr));
1344 }
1345
1346 @Override
1347 public void visitLambda(JCLambda tree) {
1348 if (sRet.hasTag(VOID)) {
1349 // do nothing
1350 } else if (tRet.hasTag(VOID)) {
1351 result = false;
1352 } else {
1353 List<JCExpression> lambdaResults = lambdaResults(tree);
1354 if (!lambdaResults.isEmpty() && unrelatedFunctionalInterfaces(tRet, sRet)) {
1355 for (JCExpression expr : lambdaResults) {
1356 result &= functionalInterfaceMostSpecific(tRet, sRet, expr);
1357 }
1358 } else if (!lambdaResults.isEmpty() && tRet.isPrimitive() != sRet.isPrimitive()) {
1359 for (JCExpression expr : lambdaResults) {
1360 boolean retValIsPrimitive = expr.isStandalone() && expr.type.isPrimitive();
1361 result &= (retValIsPrimitive == tRet.isPrimitive()) &&
1362 (retValIsPrimitive != sRet.isPrimitive());
1363 }
1364 } else {
1365 result &= compatibleBySubtyping(tRet, sRet);
1366 }
1367 }
1368 }
1369 //where
1370
1371 private List<JCExpression> lambdaResults(JCLambda lambda) {
1372 if (lambda.getBodyKind() == JCTree.JCLambda.BodyKind.EXPRESSION) {
1373 return List.of(asExpr((JCExpression) lambda.body));
1374 } else {
1375 final ListBuffer<JCExpression> buffer = new ListBuffer<>();
1376 DeferredAttr.LambdaReturnScanner lambdaScanner =
1377 new DeferredAttr.LambdaReturnScanner() {
1378 @Override
1379 public void visitReturn(JCReturn tree) {
1380 if (tree.expr != null) {
1381 buffer.append(asExpr(tree.expr));
1382 }
1383 }
1384 };
1385 lambdaScanner.scan(lambda.body);
1386 return buffer.toList();
1387 }
1388 }
1389
1390 private JCExpression asExpr(JCExpression expr) {
1391 if (expr.type.hasTag(DEFERRED)) {
1392 JCTree speculativeTree = ((DeferredType)expr.type).speculativeTree(deferredAttrContext);
1393 if (speculativeTree != deferredAttr.stuckTree) {
1394 expr = (JCExpression)speculativeTree;
1395 }
1396 }
1397 return expr;
1398 }
1399 }
1400
1401 }
1402
1403 public MethodCheck mostSpecificCheck(List<Type> actuals) {
1404 Assert.error("Cannot get here!");
1405 return null;
1406 }
1407 }
1408
1409 public static class InapplicableMethodException extends CompilerInternalException {
1410 private static final long serialVersionUID = 0;
1411
1412 transient JCDiagnostic diagnostic;
1413
1414 InapplicableMethodException(JCDiagnostic diag, boolean dumpStackTraceOnError) {
1415 super(dumpStackTraceOnError);
1416 this.diagnostic = diag;
1417 }
1418
1419 public JCDiagnostic getDiagnostic() {
1420 return diagnostic;
1421 }
1422 }
1423
1424 /* ***************************************************************************
1425 * Symbol lookup
1426 * the following naming conventions for arguments are used
1427 *
1428 * env is the environment where the symbol was mentioned
1429 * site is the type of which the symbol is a member
1430 * name is the symbol's name
1431 * if no arguments are given
1432 * argtypes are the value arguments, if we search for a method
1433 *
1434 * If no symbol was found, a ResolveError detailing the problem is returned.
1435 ****************************************************************************/
1436
1437 /** Find field. Synthetic fields are always skipped.
1438 * @param env The current environment.
1439 * @param site The original type from where the selection takes place.
1440 * @param name The name of the field.
1441 * @param c The class to search for the field. This is always
1442 * a superclass or implemented interface of site's class.
1443 */
1444 Symbol findField(Env<AttrContext> env,
1445 Type site,
1446 Name name,
1447 TypeSymbol c) {
1448 while (c.type.hasTag(TYPEVAR))
1449 c = c.type.getUpperBound().tsym;
1450 Symbol bestSoFar = varNotFound;
1451 Symbol sym;
1452 for (Symbol s : c.members().getSymbolsByName(name)) {
1453 if (s.kind == VAR && (s.flags_field & SYNTHETIC) == 0) {
1454 return isAccessible(env, site, s)
1455 ? s : new AccessError(env, site, s);
1456 }
1457 }
1458 Type st = types.supertype(c.type);
1459 if (st != null && (st.hasTag(CLASS) || st.hasTag(TYPEVAR))) {
1460 sym = findField(env, site, name, st.tsym);
1461 bestSoFar = bestOf(bestSoFar, sym);
1462 }
1463 for (List<Type> l = types.interfaces(c.type);
1464 bestSoFar.kind != AMBIGUOUS && l.nonEmpty();
1465 l = l.tail) {
1466 sym = findField(env, site, name, l.head.tsym);
1467 if (bestSoFar.exists() && sym.exists() &&
1468 sym.owner != bestSoFar.owner)
1469 bestSoFar = new AmbiguityError(bestSoFar, sym);
1470 else
1471 bestSoFar = bestOf(bestSoFar, sym);
1472 }
1473 return bestSoFar;
1474 }
1475
1476 /** Resolve a field identifier, throw a fatal error if not found.
1477 * @param pos The position to use for error reporting.
1478 * @param env The environment current at the method invocation.
1479 * @param site The type of the qualifying expression, in which
1480 * identifier is searched.
1481 * @param name The identifier's name.
1482 */
1483 public VarSymbol resolveInternalField(DiagnosticPosition pos, Env<AttrContext> env,
1484 Type site, Name name) {
1485 Symbol sym = findField(env, site, name, site.tsym);
1486 if (sym.kind == VAR) return (VarSymbol)sym;
1487 else throw new FatalError(
1488 diags.fragment(Fragments.FatalErrCantLocateField(name)));
1489 }
1490
1491 /** Find unqualified variable or field with given name.
1492 * Synthetic fields always skipped.
1493 * @param pos The position to use for error reporting.
1494 * @param env The current environment.
1495 * @param name The name of the variable or field.
1496 */
1497 Symbol findVar(DiagnosticPosition pos, Env<AttrContext> env, Name name) {
1498 Symbol bestSoFar = varNotFound;
1499 Env<AttrContext> env1 = env;
1500 boolean staticOnly = false;
1501 while (env1.outer != null) {
1502 Symbol sym = null;
1503 for (Symbol s : env1.info.scope.getSymbolsByName(name)) {
1504 if (s.kind == VAR && (s.flags_field & SYNTHETIC) == 0) {
1505 sym = s;
1506 if (staticOnly) {
1507 return new StaticError(sym);
1508 }
1509 break;
1510 }
1511 }
1512 if (isStatic(env1)) staticOnly = true;
1513 if (sym == null) {
1514 sym = findField(env1, env1.enclClass.sym.type, name, env1.enclClass.sym);
1515 }
1516 if (sym.exists()) {
1517 if (sym.kind == VAR &&
1518 sym.owner.kind == TYP &&
1519 (sym.flags() & STATIC) == 0) {
1520 if (staticOnly)
1521 return new StaticError(sym);
1522 if (env1.info.ctorPrologue && !isAllowedEarlyReference(pos, env1, (VarSymbol)sym))
1523 return new RefBeforeCtorCalledError(sym);
1524 }
1525 return sym;
1526 } else {
1527 bestSoFar = bestOf(bestSoFar, sym);
1528 }
1529
1530 if ((env1.enclClass.sym.flags() & STATIC) != 0) staticOnly = true;
1531 env1 = env1.outer;
1532 }
1533
1534 Symbol sym = findField(env, syms.predefClass.type, name, syms.predefClass);
1535 if (sym.exists())
1536 return sym;
1537 if (bestSoFar.exists())
1538 return bestSoFar;
1539
1540 Symbol origin = null;
1541 for (Scope sc : new Scope[] { env.toplevel.namedImportScope, env.toplevel.starImportScope }) {
1542 for (Symbol currentSymbol : sc.getSymbolsByName(name)) {
1543 if (currentSymbol.kind != VAR)
1544 continue;
1545 // invariant: sym.kind == Symbol.Kind.VAR
1546 if (!bestSoFar.kind.isResolutionError() &&
1547 currentSymbol.owner != bestSoFar.owner)
1548 return new AmbiguityError(bestSoFar, currentSymbol);
1549 else if (!bestSoFar.kind.betterThan(VAR)) {
1550 origin = sc.getOrigin(currentSymbol).owner;
1551 bestSoFar = isAccessible(env, origin.type, currentSymbol)
1552 ? currentSymbol : new AccessError(env, origin.type, currentSymbol);
1553 }
1554 }
1555 if (bestSoFar.exists()) break;
1556 }
1557 if (bestSoFar.kind == VAR && bestSoFar.owner.type != origin.type)
1558 return bestSoFar.clone(origin);
1559 else
1560 return bestSoFar;
1561 }
1562
1563 Warner noteWarner = new Warner();
1564
1565 /** Select the best method for a call site among two choices.
1566 * @param env The current environment.
1567 * @param site The original type from where the
1568 * selection takes place.
1569 * @param argtypes The invocation's value arguments,
1570 * @param typeargtypes The invocation's type arguments,
1571 * @param sym Proposed new best match.
1572 * @param bestSoFar Previously found best match.
1573 * @param allowBoxing Allow boxing conversions of arguments.
1574 * @param useVarargs Box trailing arguments into an array for varargs.
1575 */
1576 @SuppressWarnings("fallthrough")
1577 Symbol selectBest(Env<AttrContext> env,
1578 Type site,
1579 List<Type> argtypes,
1580 List<Type> typeargtypes,
1581 Symbol sym,
1582 Symbol bestSoFar,
1583 boolean allowBoxing,
1584 boolean useVarargs) {
1585 if (sym.kind == ERR ||
1586 (site.tsym != sym.owner && !sym.isInheritedIn(site.tsym, types)) ||
1587 !notOverriddenIn(site, sym)) {
1588 return bestSoFar;
1589 } else if (useVarargs && (sym.flags() & VARARGS) == 0) {
1590 return bestSoFar.kind.isResolutionError() ?
1591 new BadVarargsMethod((ResolveError)bestSoFar.baseSymbol()) :
1592 bestSoFar;
1593 }
1594 Assert.check(!sym.kind.isResolutionError());
1595 try {
1596 types.noWarnings.clear();
1597 Type mt = rawInstantiate(env, site, sym, null, argtypes, typeargtypes,
1598 allowBoxing, useVarargs, types.noWarnings);
1599 currentResolutionContext.addApplicableCandidate(sym, mt);
1600 } catch (InapplicableMethodException ex) {
1601 currentResolutionContext.addInapplicableCandidate(sym, ex.getDiagnostic());
1602 // Currently, an InapplicableMethodException occurs.
1603 // If bestSoFar.kind was ABSENT_MTH, return an InapplicableSymbolError(kind is WRONG_MTH).
1604 // If bestSoFar.kind was HIDDEN(AccessError)/WRONG_MTH/WRONG_MTHS, return an InapplicableSymbolsError(kind is WRONG_MTHS).
1605 // See JDK-8255968 for more information.
1606 switch (bestSoFar.kind) {
1607 case ABSENT_MTH:
1608 return new InapplicableSymbolError(currentResolutionContext);
1609 case HIDDEN:
1610 if (bestSoFar instanceof AccessError accessError) {
1611 // Add the JCDiagnostic of previous AccessError to the currentResolutionContext
1612 // and construct InapplicableSymbolsError.
1613 // Intentionally fallthrough.
1614 currentResolutionContext.addInapplicableCandidate(accessError.sym,
1615 accessError.getDiagnostic(JCDiagnostic.DiagnosticType.FRAGMENT, null, null, site, null, argtypes, typeargtypes));
1616 } else {
1617 return bestSoFar;
1618 }
1619 case WRONG_MTH:
1620 bestSoFar = new InapplicableSymbolsError(currentResolutionContext);
1621 default:
1622 return bestSoFar;
1623 }
1624 }
1625 if (!isAccessible(env, site, sym)) {
1626 AccessError curAccessError = new AccessError(env, site, sym);
1627 JCDiagnostic curDiagnostic = curAccessError.getDiagnostic(JCDiagnostic.DiagnosticType.FRAGMENT, null, null, site, null, argtypes, typeargtypes);
1628 // Currently, an AccessError occurs.
1629 // If bestSoFar.kind was ABSENT_MTH, return an AccessError(kind is HIDDEN).
1630 // If bestSoFar.kind was HIDDEN(AccessError), WRONG_MTH, WRONG_MTHS, return an InapplicableSymbolsError(kind is WRONG_MTHS).
1631 // See JDK-8255968 for more information.
1632 if (bestSoFar.kind == ABSENT_MTH) {
1633 bestSoFar = curAccessError;
1634 } else if (bestSoFar.kind == WRONG_MTH) {
1635 // Add the JCDiagnostic of current AccessError to the currentResolutionContext
1636 // and construct InapplicableSymbolsError.
1637 currentResolutionContext.addInapplicableCandidate(sym, curDiagnostic);
1638 bestSoFar = new InapplicableSymbolsError(currentResolutionContext);
1639 } else if (bestSoFar.kind == WRONG_MTHS) {
1640 // Add the JCDiagnostic of current AccessError to the currentResolutionContext
1641 currentResolutionContext.addInapplicableCandidate(sym, curDiagnostic);
1642 } else if (bestSoFar.kind == HIDDEN && bestSoFar instanceof AccessError accessError) {
1643 // Add the JCDiagnostics of previous and current AccessError to the currentResolutionContext
1644 // and construct InapplicableSymbolsError.
1645 currentResolutionContext.addInapplicableCandidate(accessError.sym,
1646 accessError.getDiagnostic(JCDiagnostic.DiagnosticType.FRAGMENT, null, null, site, null, argtypes, typeargtypes));
1647 currentResolutionContext.addInapplicableCandidate(sym, curDiagnostic);
1648 bestSoFar = new InapplicableSymbolsError(currentResolutionContext);
1649 }
1650 return bestSoFar;
1651 }
1652 return (bestSoFar.kind.isResolutionError() && bestSoFar.kind != AMBIGUOUS)
1653 ? sym
1654 : mostSpecific(argtypes, sym, bestSoFar, env, site, useVarargs);
1655 }
1656
1657 /* Return the most specific of the two methods for a call,
1658 * given that both are accessible and applicable.
1659 * @param m1 A new candidate for most specific.
1660 * @param m2 The previous most specific candidate.
1661 * @param env The current environment.
1662 * @param site The original type from where the selection
1663 * takes place.
1664 * @param allowBoxing Allow boxing conversions of arguments.
1665 * @param useVarargs Box trailing arguments into an array for varargs.
1666 */
1667 Symbol mostSpecific(List<Type> argtypes, Symbol m1,
1668 Symbol m2,
1669 Env<AttrContext> env,
1670 final Type site,
1671 boolean useVarargs) {
1672 switch (m2.kind) {
1673 case MTH:
1674 if (m1 == m2) return m1;
1675 boolean m1SignatureMoreSpecific =
1676 signatureMoreSpecific(argtypes, env, site, m1, m2, useVarargs);
1677 boolean m2SignatureMoreSpecific =
1678 signatureMoreSpecific(argtypes, env, site, m2, m1, useVarargs);
1679 if (m1SignatureMoreSpecific && m2SignatureMoreSpecific) {
1680 Type mt1 = types.memberType(site, m1);
1681 Type mt2 = types.memberType(site, m2);
1682 if (!types.overrideEquivalent(mt1, mt2))
1683 return ambiguityError(m1, m2);
1684
1685 // same signature; select (a) the non-bridge method, or
1686 // (b) the one that overrides the other, or (c) the concrete
1687 // one, or (d) merge both abstract signatures
1688 if ((m1.flags() & BRIDGE) != (m2.flags() & BRIDGE))
1689 return ((m1.flags() & BRIDGE) != 0) ? m2 : m1;
1690
1691 if (m1.baseSymbol() == m2.baseSymbol()) {
1692 // this is the same imported symbol which has been cloned twice.
1693 // Return the first one (either will do).
1694 return m1;
1695 }
1696
1697 // if one overrides or hides the other, use it
1698 TypeSymbol m1Owner = (TypeSymbol)m1.owner;
1699 TypeSymbol m2Owner = (TypeSymbol)m2.owner;
1700 // the two owners can never be the same if the target methods are compiled from source,
1701 // but we need to protect against cases where the methods are defined in some classfile
1702 // and make sure we issue an ambiguity error accordingly (by skipping the logic below).
1703 if (m1Owner != m2Owner) {
1704 if (types.asSuper(m1Owner.type, m2Owner) != null &&
1705 ((m1.owner.flags_field & INTERFACE) == 0 ||
1706 (m2.owner.flags_field & INTERFACE) != 0) &&
1707 m1.overrides(m2, m1Owner, types, false))
1708 return m1;
1709 if (types.asSuper(m2Owner.type, m1Owner) != null &&
1710 ((m2.owner.flags_field & INTERFACE) == 0 ||
1711 (m1.owner.flags_field & INTERFACE) != 0) &&
1712 m2.overrides(m1, m2Owner, types, false))
1713 return m2;
1714 }
1715 boolean m1Abstract = (m1.flags() & ABSTRACT) != 0;
1716 boolean m2Abstract = (m2.flags() & ABSTRACT) != 0;
1717 if (m1Abstract && !m2Abstract) return m2;
1718 if (m2Abstract && !m1Abstract) return m1;
1719 // both abstract or both concrete
1720 return ambiguityError(m1, m2);
1721 }
1722 if (m1SignatureMoreSpecific) return m1;
1723 if (m2SignatureMoreSpecific) return m2;
1724 return ambiguityError(m1, m2);
1725 case AMBIGUOUS:
1726 //compare m1 to ambiguous methods in m2
1727 AmbiguityError e = (AmbiguityError)m2.baseSymbol();
1728 boolean m1MoreSpecificThanAnyAmbiguous = true;
1729 boolean allAmbiguousMoreSpecificThanM1 = true;
1730 for (Symbol s : e.ambiguousSyms) {
1731 Symbol moreSpecific = mostSpecific(argtypes, m1, s, env, site, useVarargs);
1732 m1MoreSpecificThanAnyAmbiguous &= moreSpecific == m1;
1733 allAmbiguousMoreSpecificThanM1 &= moreSpecific == s;
1734 }
1735 if (m1MoreSpecificThanAnyAmbiguous)
1736 return m1;
1737 //if m1 is more specific than some ambiguous methods, but other ambiguous methods are
1738 //more specific than m1, add it as a new ambiguous method:
1739 if (!allAmbiguousMoreSpecificThanM1)
1740 e.addAmbiguousSymbol(m1);
1741 return e;
1742 default:
1743 throw new AssertionError();
1744 }
1745 }
1746 //where
1747 private boolean signatureMoreSpecific(List<Type> actuals, Env<AttrContext> env, Type site, Symbol m1, Symbol m2, boolean useVarargs) {
1748 noteWarner.clear();
1749 int maxLength = Math.max(
1750 Math.max(m1.type.getParameterTypes().length(), actuals.length()),
1751 m2.type.getParameterTypes().length());
1752 MethodResolutionContext prevResolutionContext = currentResolutionContext;
1753 try {
1754 currentResolutionContext = new MethodResolutionContext();
1755 currentResolutionContext.step = prevResolutionContext.step;
1756 currentResolutionContext.methodCheck =
1757 prevResolutionContext.methodCheck.mostSpecificCheck(actuals);
1758 Type mst = instantiate(env, site, m2, null,
1759 adjustArgs(types.cvarLowerBounds(types.memberType(site, m1).getParameterTypes()), m1, maxLength, useVarargs), null,
1760 false, useVarargs, noteWarner);
1761 return mst != null &&
1762 !noteWarner.hasLint(Lint.LintCategory.UNCHECKED);
1763 } finally {
1764 currentResolutionContext = prevResolutionContext;
1765 }
1766 }
1767
1768 List<Type> adjustArgs(List<Type> args, Symbol msym, int length, boolean allowVarargs) {
1769 if ((msym.flags() & VARARGS) != 0 && allowVarargs) {
1770 Type varargsElem = types.elemtype(args.last());
1771 if (varargsElem == null) {
1772 Assert.error("Bad varargs = " + args.last() + " " + msym);
1773 }
1774 List<Type> newArgs = args.reverse().tail.prepend(varargsElem).reverse();
1775 while (newArgs.length() < length) {
1776 newArgs = newArgs.append(newArgs.last());
1777 }
1778 return newArgs;
1779 } else {
1780 return args;
1781 }
1782 }
1783 //where
1784 Symbol ambiguityError(Symbol m1, Symbol m2) {
1785 if (((m1.flags() | m2.flags()) & CLASH) != 0) {
1786 return (m1.flags() & CLASH) == 0 ? m1 : m2;
1787 } else {
1788 return new AmbiguityError(m1, m2);
1789 }
1790 }
1791
1792 Symbol findMethodInScope(Env<AttrContext> env,
1793 Type site,
1794 Name name,
1795 List<Type> argtypes,
1796 List<Type> typeargtypes,
1797 Scope sc,
1798 Symbol bestSoFar,
1799 boolean allowBoxing,
1800 boolean useVarargs,
1801 boolean abstractok) {
1802 for (Symbol s : sc.getSymbolsByName(name, new LookupFilter(abstractok))) {
1803 bestSoFar = selectBest(env, site, argtypes, typeargtypes, s,
1804 bestSoFar, allowBoxing, useVarargs);
1805 }
1806 return bestSoFar;
1807 }
1808 //where
1809 class LookupFilter implements Predicate<Symbol> {
1810
1811 boolean abstractOk;
1812
1813 LookupFilter(boolean abstractOk) {
1814 this.abstractOk = abstractOk;
1815 }
1816
1817 @Override
1818 public boolean test(Symbol s) {
1819 long flags = s.flags();
1820 return s.kind == MTH &&
1821 (flags & SYNTHETIC) == 0 &&
1822 (abstractOk ||
1823 (flags & DEFAULT) != 0 ||
1824 (flags & ABSTRACT) == 0);
1825 }
1826 }
1827
1828 /** Find best qualified method matching given name, type and value
1829 * arguments.
1830 * @param env The current environment.
1831 * @param site The original type from where the selection
1832 * takes place.
1833 * @param name The method's name.
1834 * @param argtypes The method's value arguments.
1835 * @param typeargtypes The method's type arguments
1836 * @param allowBoxing Allow boxing conversions of arguments.
1837 * @param useVarargs Box trailing arguments into an array for varargs.
1838 */
1839 Symbol findMethod(Env<AttrContext> env,
1840 Type site,
1841 Name name,
1842 List<Type> argtypes,
1843 List<Type> typeargtypes,
1844 boolean allowBoxing,
1845 boolean useVarargs) {
1846 Symbol bestSoFar = methodNotFound;
1847 bestSoFar = findMethod(env,
1848 site,
1849 name,
1850 argtypes,
1851 typeargtypes,
1852 site.tsym.type,
1853 bestSoFar,
1854 allowBoxing,
1855 useVarargs);
1856 if (bestSoFar.kind == AMBIGUOUS) {
1857 AmbiguityError a_err = (AmbiguityError)bestSoFar.baseSymbol();
1858 bestSoFar = a_err.mergeAbstracts(site);
1859 }
1860 return bestSoFar;
1861 }
1862 // where
1863 private Symbol findMethod(Env<AttrContext> env,
1864 Type site,
1865 Name name,
1866 List<Type> argtypes,
1867 List<Type> typeargtypes,
1868 Type intype,
1869 Symbol bestSoFar,
1870 boolean allowBoxing,
1871 boolean useVarargs) {
1872 @SuppressWarnings({"unchecked","rawtypes"})
1873 List<Type>[] itypes = (List<Type>[])new List[] { List.<Type>nil(), List.<Type>nil() };
1874
1875 InterfaceLookupPhase iphase = InterfaceLookupPhase.ABSTRACT_OK;
1876 boolean isInterface = site.tsym.isInterface();
1877 for (TypeSymbol s : isInterface ? List.of(intype.tsym) : superclasses(intype)) {
1878 bestSoFar = findMethodInScope(env, site, name, argtypes, typeargtypes,
1879 s.members(), bestSoFar, allowBoxing, useVarargs, true);
1880 if (name == names.init) return bestSoFar;
1881 iphase = (iphase == null) ? null : iphase.update(s, this);
1882 if (iphase != null) {
1883 for (Type itype : types.interfaces(s.type)) {
1884 itypes[iphase.ordinal()] = types.union(types.closure(itype), itypes[iphase.ordinal()]);
1885 }
1886 }
1887 }
1888
1889 Symbol concrete = bestSoFar.kind.isValid() &&
1890 (bestSoFar.flags() & ABSTRACT) == 0 ?
1891 bestSoFar : methodNotFound;
1892
1893 for (InterfaceLookupPhase iphase2 : InterfaceLookupPhase.values()) {
1894 //keep searching for abstract methods
1895 for (Type itype : itypes[iphase2.ordinal()]) {
1896 if (!itype.isInterface()) continue; //skip j.l.Object (included by Types.closure())
1897 if (iphase2 == InterfaceLookupPhase.DEFAULT_OK &&
1898 (itype.tsym.flags() & DEFAULT) == 0) continue;
1899 bestSoFar = findMethodInScope(env, site, name, argtypes, typeargtypes,
1900 itype.tsym.members(), bestSoFar, allowBoxing, useVarargs, true);
1901 if (concrete != bestSoFar &&
1902 concrete.kind.isValid() &&
1903 bestSoFar.kind.isValid() &&
1904 types.isSubSignature(concrete.type, bestSoFar.type)) {
1905 //this is an hack - as javac does not do full membership checks
1906 //most specific ends up comparing abstract methods that might have
1907 //been implemented by some concrete method in a subclass and,
1908 //because of raw override, it is possible for an abstract method
1909 //to be more specific than the concrete method - so we need
1910 //to explicitly call that out (see CR 6178365)
1911 bestSoFar = concrete;
1912 }
1913 }
1914 }
1915 if (isInterface && bestSoFar.kind.isResolutionError()) {
1916 bestSoFar = findMethodInScope(env, site, name, argtypes, typeargtypes,
1917 syms.objectType.tsym.members(), bestSoFar, allowBoxing, useVarargs, true);
1918 if (bestSoFar.kind.isValid()) {
1919 Symbol baseSymbol = bestSoFar;
1920 bestSoFar = new MethodSymbol(bestSoFar.flags_field, bestSoFar.name, bestSoFar.type, intype.tsym) {
1921 @Override
1922 public Symbol baseSymbol() {
1923 return baseSymbol;
1924 }
1925 };
1926 }
1927 }
1928 return bestSoFar;
1929 }
1930
1931 enum InterfaceLookupPhase {
1932 ABSTRACT_OK() {
1933 @Override
1934 InterfaceLookupPhase update(Symbol s, Resolve rs) {
1935 //We should not look for abstract methods if receiver is a concrete class
1936 //(as concrete classes are expected to implement all abstracts coming
1937 //from superinterfaces)
1938 if ((s.flags() & (ABSTRACT | INTERFACE | ENUM)) != 0) {
1939 return this;
1940 } else {
1941 return DEFAULT_OK;
1942 }
1943 }
1944 },
1945 DEFAULT_OK() {
1946 @Override
1947 InterfaceLookupPhase update(Symbol s, Resolve rs) {
1948 return this;
1949 }
1950 };
1951
1952 abstract InterfaceLookupPhase update(Symbol s, Resolve rs);
1953 }
1954
1955 /**
1956 * Return an Iterable object to scan the superclasses of a given type.
1957 * It's crucial that the scan is done lazily, as we don't want to accidentally
1958 * access more supertypes than strictly needed (as this could trigger completion
1959 * errors if some of the not-needed supertypes are missing/ill-formed).
1960 */
1961 Iterable<TypeSymbol> superclasses(final Type intype) {
1962 return () -> new Iterator<TypeSymbol>() {
1963
1964 List<TypeSymbol> seen = List.nil();
1965 TypeSymbol currentSym = symbolFor(intype);
1966 TypeSymbol prevSym = null;
1967
1968 public boolean hasNext() {
1969 if (currentSym == syms.noSymbol) {
1970 currentSym = symbolFor(types.supertype(prevSym.type));
1971 }
1972 return currentSym != null;
1973 }
1974
1975 public TypeSymbol next() {
1976 prevSym = currentSym;
1977 currentSym = syms.noSymbol;
1978 Assert.check(prevSym != null || prevSym != syms.noSymbol);
1979 return prevSym;
1980 }
1981
1982 public void remove() {
1983 throw new UnsupportedOperationException();
1984 }
1985
1986 TypeSymbol symbolFor(Type t) {
1987 if (!t.hasTag(CLASS) &&
1988 !t.hasTag(TYPEVAR)) {
1989 return null;
1990 }
1991 t = types.skipTypeVars(t, false);
1992 if (seen.contains(t.tsym)) {
1993 //degenerate case in which we have a circular
1994 //class hierarchy - because of ill-formed classfiles
1995 return null;
1996 }
1997 seen = seen.prepend(t.tsym);
1998 return t.tsym;
1999 }
2000 };
2001 }
2002
2003 /** Find unqualified method matching given name, type and value arguments.
2004 * @param env The current environment.
2005 * @param name The method's name.
2006 * @param argtypes The method's value arguments.
2007 * @param typeargtypes The method's type arguments.
2008 * @param allowBoxing Allow boxing conversions of arguments.
2009 * @param useVarargs Box trailing arguments into an array for varargs.
2010 */
2011 Symbol findFun(Env<AttrContext> env, Name name,
2012 List<Type> argtypes, List<Type> typeargtypes,
2013 boolean allowBoxing, boolean useVarargs) {
2014 Symbol bestSoFar = methodNotFound;
2015 Env<AttrContext> env1 = env;
2016 boolean staticOnly = false;
2017 while (env1.outer != null) {
2018 if (isStatic(env1)) staticOnly = true;
2019 Assert.check(env1.info.preferredTreeForDiagnostics == null);
2020 env1.info.preferredTreeForDiagnostics = env.tree;
2021 try {
2022 Symbol sym = findMethod(
2023 env1, env1.enclClass.sym.type, name, argtypes, typeargtypes,
2024 allowBoxing, useVarargs);
2025 if (sym.exists()) {
2026 if (sym.kind == MTH &&
2027 sym.owner.kind == TYP &&
2028 (sym.flags() & STATIC) == 0) {
2029 if (staticOnly)
2030 return new StaticError(sym);
2031 if (env1.info.ctorPrologue && env1 == env)
2032 return new RefBeforeCtorCalledError(sym);
2033 }
2034 return sym;
2035 } else {
2036 bestSoFar = bestOf(bestSoFar, sym);
2037 }
2038 } finally {
2039 env1.info.preferredTreeForDiagnostics = null;
2040 }
2041 if ((env1.enclClass.sym.flags() & STATIC) != 0) staticOnly = true;
2042 env1 = env1.outer;
2043 }
2044
2045 Symbol sym = findMethod(env, syms.predefClass.type, name, argtypes,
2046 typeargtypes, allowBoxing, useVarargs);
2047 if (sym.exists())
2048 return sym;
2049
2050 for (Symbol currentSym : env.toplevel.namedImportScope.getSymbolsByName(name)) {
2051 Symbol origin = env.toplevel.namedImportScope.getOrigin(currentSym).owner;
2052 if (currentSym.kind == MTH) {
2053 if (currentSym.owner.type != origin.type)
2054 currentSym = currentSym.clone(origin);
2055 if (!isAccessible(env, origin.type, currentSym))
2056 currentSym = new AccessError(env, origin.type, currentSym);
2057 bestSoFar = selectBest(env, origin.type,
2058 argtypes, typeargtypes,
2059 currentSym, bestSoFar,
2060 allowBoxing, useVarargs);
2061 }
2062 }
2063 if (bestSoFar.exists())
2064 return bestSoFar;
2065
2066 for (Symbol currentSym : env.toplevel.starImportScope.getSymbolsByName(name)) {
2067 Symbol origin = env.toplevel.starImportScope.getOrigin(currentSym).owner;
2068 if (currentSym.kind == MTH) {
2069 if (currentSym.owner.type != origin.type)
2070 currentSym = currentSym.clone(origin);
2071 if (!isAccessible(env, origin.type, currentSym))
2072 currentSym = new AccessError(env, origin.type, currentSym);
2073 bestSoFar = selectBest(env, origin.type,
2074 argtypes, typeargtypes,
2075 currentSym, bestSoFar,
2076 allowBoxing, useVarargs);
2077 }
2078 }
2079 return bestSoFar;
2080 }
2081
2082 /** Load toplevel or member class with given fully qualified name and
2083 * verify that it is accessible.
2084 * @param env The current environment.
2085 * @param name The fully qualified name of the class to be loaded.
2086 */
2087 Symbol loadClass(Env<AttrContext> env, Name name, RecoveryLoadClass recoveryLoadClass) {
2088 try {
2089 ClassSymbol c = finder.loadClass(env.toplevel.modle, name);
2090 return isAccessible(env, c) ? c : new AccessError(env, null, c);
2091 } catch (ClassFinder.BadClassFile err) {
2092 return new BadClassFileError(err);
2093 } catch (CompletionFailure ex) {
2094 Symbol candidate = recoveryLoadClass.loadClass(env, name);
2095
2096 if (candidate != null) {
2097 return candidate;
2098 }
2099
2100 return typeNotFound;
2101 }
2102 }
2103
2104 public interface RecoveryLoadClass {
2105 Symbol loadClass(Env<AttrContext> env, Name name);
2106 }
2107
2108 private final RecoveryLoadClass noRecovery = (env, name) -> null;
2109
2110 private final RecoveryLoadClass doRecoveryLoadClass = new RecoveryLoadClass() {
2111 @Override public Symbol loadClass(Env<AttrContext> env, Name name) {
2112 List<Name> candidates = Convert.classCandidates(name);
2113 return lookupInvisibleSymbol(env, name,
2114 n -> () -> createCompoundIterator(candidates,
2115 c -> syms.getClassesForName(c)
2116 .iterator()),
2117 (ms, n) -> {
2118 for (Name candidate : candidates) {
2119 try {
2120 return finder.loadClass(ms, candidate);
2121 } catch (CompletionFailure cf) {
2122 //ignore
2123 }
2124 }
2125 return null;
2126 }, sym -> sym.kind == Kind.TYP, typeNotFound);
2127 }
2128 };
2129
2130 private final RecoveryLoadClass namedImportScopeRecovery = (env, name) -> {
2131 Scope importScope = env.toplevel.namedImportScope;
2132 Symbol existing = importScope.findFirst(Convert.shortName(name),
2133 sym -> sym.kind == TYP && sym.flatName() == name);
2134
2135 if (existing != null) {
2136 return new InvisibleSymbolError(env, true, existing);
2137 }
2138 return null;
2139 };
2140
2141 private final RecoveryLoadClass starImportScopeRecovery = (env, name) -> {
2142 Scope importScope = env.toplevel.starImportScope;
2143 Symbol existing = importScope.findFirst(Convert.shortName(name),
2144 sym -> sym.kind == TYP && sym.flatName() == name);
2145
2146 if (existing != null) {
2147 try {
2148 existing = finder.loadClass(existing.packge().modle, name);
2149
2150 return new InvisibleSymbolError(env, true, existing);
2151 } catch (CompletionFailure cf) {
2152 //ignore
2153 }
2154 }
2155
2156 return null;
2157 };
2158
2159 Symbol lookupPackage(Env<AttrContext> env, Name name) {
2160 PackageSymbol pack = syms.lookupPackage(env.toplevel.modle, name);
2161
2162 if (allowModules && isImportOnDemand(env, name)) {
2163 if (pack.members().isEmpty()) {
2164 return lookupInvisibleSymbol(env, name, syms::getPackagesForName, syms::enterPackage, sym -> {
2165 sym.complete();
2166 return !sym.members().isEmpty();
2167 }, pack);
2168 }
2169 }
2170
2171 return pack;
2172 }
2173
2174 private boolean isImportOnDemand(Env<AttrContext> env, Name name) {
2175 if (!env.tree.hasTag(IMPORT))
2176 return false;
2177
2178 JCTree qualid = ((JCImport) env.tree).qualid;
2179
2180 if (!qualid.hasTag(SELECT))
2181 return false;
2182
2183 if (TreeInfo.name(qualid) != names.asterisk)
2184 return false;
2185
2186 return TreeInfo.fullName(((JCFieldAccess) qualid).selected) == name;
2187 }
2188
2189 private <S extends Symbol> Symbol lookupInvisibleSymbol(Env<AttrContext> env,
2190 Name name,
2191 Function<Name, Iterable<S>> get,
2192 BiFunction<ModuleSymbol, Name, S> load,
2193 Predicate<S> validate,
2194 Symbol defaultResult) {
2195 //even if a class/package cannot be found in the current module and among packages in modules
2196 //it depends on that are exported for any or this module, the class/package may exist internally
2197 //in some of these modules, or may exist in a module on which this module does not depend.
2198 //Provide better diagnostic in such cases by looking for the class in any module:
2199 Iterable<? extends S> candidates = get.apply(name);
2200
2201 for (S sym : candidates) {
2202 if (validate.test(sym))
2203 return createInvisibleSymbolError(env, sym);
2204 }
2205
2206 Set<ModuleSymbol> recoverableModules = new HashSet<>(syms.getAllModules());
2207
2208 recoverableModules.add(syms.unnamedModule);
2209 recoverableModules.remove(env.toplevel.modle);
2210
2211 for (ModuleSymbol ms : recoverableModules) {
2212 //avoid overly eager completing classes from source-based modules, as those
2213 //may not be completable with the current compiler settings:
2214 if (ms.sourceLocation == null) {
2215 if (ms.classLocation == null) {
2216 ms = moduleFinder.findModule(ms);
2217 }
2218
2219 if (ms.kind != ERR) {
2220 S sym = load.apply(ms, name);
2221
2222 if (sym != null && validate.test(sym)) {
2223 return createInvisibleSymbolError(env, sym);
2224 }
2225 }
2226 }
2227 }
2228
2229 return defaultResult;
2230 }
2231
2232 private Symbol createInvisibleSymbolError(Env<AttrContext> env, Symbol sym) {
2233 if (symbolPackageVisible(env, sym)) {
2234 return new AccessError(env, null, sym);
2235 } else {
2236 return new InvisibleSymbolError(env, false, sym);
2237 }
2238 }
2239
2240 private boolean symbolPackageVisible(Env<AttrContext> env, Symbol sym) {
2241 ModuleSymbol envMod = env.toplevel.modle;
2242 PackageSymbol symPack = sym.packge();
2243 return envMod == symPack.modle ||
2244 envMod.visiblePackages.containsKey(symPack.fullname);
2245 }
2246
2247 /**
2248 * Find a type declared in a scope (not inherited). Return null
2249 * if none is found.
2250 * @param env The current environment.
2251 * @param site The original type from where the selection takes
2252 * place.
2253 * @param name The type's name.
2254 * @param c The class to search for the member type. This is
2255 * always a superclass or implemented interface of
2256 * site's class.
2257 */
2258 Symbol findImmediateMemberType(Env<AttrContext> env,
2259 Type site,
2260 Name name,
2261 TypeSymbol c) {
2262 for (Symbol sym : c.members().getSymbolsByName(name)) {
2263 if (sym.kind == TYP) {
2264 return isAccessible(env, site, sym)
2265 ? sym
2266 : new AccessError(env, site, sym);
2267 }
2268 }
2269 return typeNotFound;
2270 }
2271
2272 /** Find a member type inherited from a superclass or interface.
2273 * @param env The current environment.
2274 * @param site The original type from where the selection takes
2275 * place.
2276 * @param name The type's name.
2277 * @param c The class to search for the member type. This is
2278 * always a superclass or implemented interface of
2279 * site's class.
2280 */
2281 Symbol findInheritedMemberType(Env<AttrContext> env,
2282 Type site,
2283 Name name,
2284 TypeSymbol c) {
2285 Symbol bestSoFar = typeNotFound;
2286 Symbol sym;
2287 Type st = types.supertype(c.type);
2288 if (st != null && st.hasTag(CLASS)) {
2289 sym = findMemberType(env, site, name, st.tsym);
2290 bestSoFar = bestOf(bestSoFar, sym);
2291 }
2292 for (List<Type> l = types.interfaces(c.type);
2293 bestSoFar.kind != AMBIGUOUS && l.nonEmpty();
2294 l = l.tail) {
2295 sym = findMemberType(env, site, name, l.head.tsym);
2296 if (!bestSoFar.kind.isResolutionError() &&
2297 !sym.kind.isResolutionError() &&
2298 sym.owner != bestSoFar.owner)
2299 bestSoFar = new AmbiguityError(bestSoFar, sym);
2300 else
2301 bestSoFar = bestOf(bestSoFar, sym);
2302 }
2303 return bestSoFar;
2304 }
2305
2306 /** Find qualified member type.
2307 * @param env The current environment.
2308 * @param site The original type from where the selection takes
2309 * place.
2310 * @param name The type's name.
2311 * @param c The class to search for the member type. This is
2312 * always a superclass or implemented interface of
2313 * site's class.
2314 */
2315 Symbol findMemberType(Env<AttrContext> env,
2316 Type site,
2317 Name name,
2318 TypeSymbol c) {
2319 Symbol sym = findImmediateMemberType(env, site, name, c);
2320
2321 if (sym != typeNotFound)
2322 return sym;
2323
2324 return findInheritedMemberType(env, site, name, c);
2325
2326 }
2327
2328 /** Find a global type in given scope and load corresponding class.
2329 * @param env The current environment.
2330 * @param scope The scope in which to look for the type.
2331 * @param name The type's name.
2332 */
2333 Symbol findGlobalType(Env<AttrContext> env, Scope scope, Name name, RecoveryLoadClass recoveryLoadClass) {
2334 Symbol bestSoFar = typeNotFound;
2335 for (Symbol s : scope.getSymbolsByName(name)) {
2336 Symbol sym = loadClass(env, s.flatName(), recoveryLoadClass);
2337 if (bestSoFar.kind == TYP && sym.kind == TYP &&
2338 bestSoFar != sym)
2339 return new AmbiguityError(bestSoFar, sym);
2340 else
2341 bestSoFar = bestOf(bestSoFar, sym);
2342 }
2343 return bestSoFar;
2344 }
2345
2346 Symbol findTypeVar(Env<AttrContext> env, Name name, boolean staticOnly) {
2347 for (Symbol sym : env.info.scope.getSymbolsByName(name)) {
2348 if (sym.kind == TYP) {
2349 if (sym.type.hasTag(TYPEVAR) &&
2350 (staticOnly || (isStatic(env) && sym.owner.kind == TYP)))
2351 // if staticOnly is set, it means that we have recursed through a static declaration,
2352 // so type variable symbols should not be accessible. If staticOnly is unset, but
2353 // we are in a static declaration (field or method), we should not allow type-variables
2354 // defined in the enclosing class to "leak" into this context.
2355 return new StaticError(sym);
2356 return sym;
2357 }
2358 }
2359 return typeNotFound;
2360 }
2361
2362 /** Find an unqualified type symbol.
2363 * @param env The current environment.
2364 * @param name The type's name.
2365 */
2366 Symbol findType(Env<AttrContext> env, Name name) {
2367 if (name == names.empty)
2368 return typeNotFound; // do not allow inadvertent "lookup" of anonymous types
2369 Symbol bestSoFar = typeNotFound;
2370 Symbol sym;
2371 boolean staticOnly = false;
2372 for (Env<AttrContext> env1 = env; env1.outer != null; env1 = env1.outer) {
2373 // First, look for a type variable and the first member type
2374 final Symbol tyvar = findTypeVar(env1, name, staticOnly);
2375 if (isStatic(env1)) staticOnly = true;
2376 sym = findImmediateMemberType(env1, env1.enclClass.sym.type,
2377 name, env1.enclClass.sym);
2378
2379 // Return the type variable if we have it, and have no
2380 // immediate member, OR the type variable is for a method.
2381 if (tyvar != typeNotFound) {
2382 if (env.baseClause || sym == typeNotFound ||
2383 (tyvar.kind == TYP && tyvar.exists() &&
2384 tyvar.owner.kind == MTH)) {
2385 return tyvar;
2386 }
2387 }
2388
2389 // If the environment is a class def, finish up,
2390 // otherwise, do the entire findMemberType
2391 if (sym == typeNotFound)
2392 sym = findInheritedMemberType(env1, env1.enclClass.sym.type,
2393 name, env1.enclClass.sym);
2394
2395 if (staticOnly && sym.kind == TYP &&
2396 sym.type.hasTag(CLASS) &&
2397 sym.type.getEnclosingType().hasTag(CLASS) &&
2398 env1.enclClass.sym.type.isParameterized() &&
2399 sym.type.getEnclosingType().isParameterized())
2400 return new StaticError(sym);
2401 else if (sym.exists()) return sym;
2402 else bestSoFar = bestOf(bestSoFar, sym);
2403
2404 JCClassDecl encl = env1.baseClause ? (JCClassDecl)env1.tree : env1.enclClass;
2405 if ((encl.sym.flags() & STATIC) != 0)
2406 staticOnly = true;
2407 }
2408
2409 if (!env.tree.hasTag(IMPORT)) {
2410 sym = findGlobalType(env, env.toplevel.namedImportScope, name, namedImportScopeRecovery);
2411 if (sym.exists()) return sym;
2412 else bestSoFar = bestOf(bestSoFar, sym);
2413
2414 sym = findGlobalType(env, env.toplevel.toplevelScope, name, noRecovery);
2415 if (sym.exists()) return sym;
2416 else bestSoFar = bestOf(bestSoFar, sym);
2417
2418 sym = findGlobalType(env, env.toplevel.packge.members(), name, noRecovery);
2419 if (sym.exists()) return sym;
2420 else bestSoFar = bestOf(bestSoFar, sym);
2421
2422 sym = findGlobalType(env, env.toplevel.starImportScope, name, starImportScopeRecovery);
2423 if (sym.exists()) return sym;
2424 else bestSoFar = bestOf(bestSoFar, sym);
2425 }
2426
2427 return bestSoFar;
2428 }
2429
2430 /** Find an unqualified identifier which matches a specified kind set.
2431 * @param pos position on which report warnings, if any;
2432 * null warnings should not be reported
2433 * @param env The current environment.
2434 * @param name The identifier's name.
2435 * @param kind Indicates the possible symbol kinds
2436 * (a subset of VAL, TYP, PCK).
2437 */
2438 Symbol findIdent(DiagnosticPosition pos, Env<AttrContext> env, Name name, KindSelector kind) {
2439 try {
2440 return checkNonExistentType(checkRestrictedType(pos, findIdentInternal(pos, env, name, kind), name));
2441 } catch (ClassFinder.BadClassFile err) {
2442 return new BadClassFileError(err);
2443 } catch (CompletionFailure cf) {
2444 chk.completionError(pos, cf);
2445 return typeNotFound;
2446 }
2447 }
2448
2449 Symbol findIdentInternal(DiagnosticPosition pos, Env<AttrContext> env, Name name, KindSelector kind) {
2450 Symbol bestSoFar = typeNotFound;
2451 Symbol sym;
2452
2453 if (kind.contains(KindSelector.VAL)) {
2454 sym = findVar(pos, env, name);
2455 if (sym.exists()) return sym;
2456 else bestSoFar = bestOf(bestSoFar, sym);
2457 }
2458
2459 if (kind.contains(KindSelector.TYP)) {
2460 sym = findType(env, name);
2461 if (sym.exists()) return sym;
2462 else bestSoFar = bestOf(bestSoFar, sym);
2463 }
2464
2465 if (kind.contains(KindSelector.PCK))
2466 return lookupPackage(env, name);
2467 else return bestSoFar;
2468 }
2469
2470 /** Find an identifier in a package which matches a specified kind set.
2471 * @param pos position on which report warnings, if any;
2472 * null warnings should not be reported
2473 * @param env The current environment.
2474 * @param name The identifier's name.
2475 * @param kind Indicates the possible symbol kinds
2476 * (a nonempty subset of TYP, PCK).
2477 */
2478 Symbol findIdentInPackage(DiagnosticPosition pos,
2479 Env<AttrContext> env, TypeSymbol pck,
2480 Name name, KindSelector kind) {
2481 return checkNonExistentType(checkRestrictedType(pos, findIdentInPackageInternal(env, pck, name, kind), name));
2482 }
2483
2484 Symbol findIdentInPackageInternal(Env<AttrContext> env, TypeSymbol pck,
2485 Name name, KindSelector kind) {
2486 Name fullname = TypeSymbol.formFullName(name, pck);
2487 Symbol bestSoFar = typeNotFound;
2488 if (kind.contains(KindSelector.TYP)) {
2489 RecoveryLoadClass recoveryLoadClass =
2490 allowModules && !kind.contains(KindSelector.PCK) &&
2491 !pck.exists() && !env.info.attributionMode.isSpeculative ?
2492 doRecoveryLoadClass : noRecovery;
2493 Symbol sym = loadClass(env, fullname, recoveryLoadClass);
2494 if (sym.exists()) {
2495 // don't allow programs to use flatnames
2496 if (name == sym.name) return sym;
2497 }
2498 else bestSoFar = bestOf(bestSoFar, sym);
2499 }
2500 if (kind.contains(KindSelector.PCK)) {
2501 return lookupPackage(env, fullname);
2502 }
2503 return bestSoFar;
2504 }
2505
2506 /** Find an identifier among the members of a given type `site'.
2507 * @param pos position on which report warnings, if any;
2508 * null warnings should not be reported
2509 * @param env The current environment.
2510 * @param site The type containing the symbol to be found.
2511 * @param name The identifier's name.
2512 * @param kind Indicates the possible symbol kinds
2513 * (a subset of VAL, TYP).
2514 */
2515 Symbol findIdentInType(DiagnosticPosition pos,
2516 Env<AttrContext> env, Type site,
2517 Name name, KindSelector kind) {
2518 try {
2519 return checkNonExistentType(checkRestrictedType(pos, findIdentInTypeInternal(env, site, name, kind), name));
2520 } catch (ClassFinder.BadClassFile err) {
2521 return new BadClassFileError(err);
2522 } catch (CompletionFailure cf) {
2523 chk.completionError(pos, cf);
2524 return typeNotFound;
2525 }
2526 }
2527
2528 private Symbol checkNonExistentType(Symbol symbol) {
2529 /* Guard against returning a type is not on the class path of the current compilation,
2530 * but *was* on the class path of a separate compilation that produced a class file
2531 * that is on the class path of the current compilation. Such a type will fail completion
2532 * but the completion failure may have been silently swallowed (e.g. missing annotation types)
2533 * with an error stub symbol lingering in the symbol tables.
2534 */
2535 return symbol instanceof ClassSymbol c && c.type.isErroneous() && c.classfile == null ? typeNotFound : symbol;
2536 }
2537
2538 Symbol findIdentInTypeInternal(Env<AttrContext> env, Type site,
2539 Name name, KindSelector kind) {
2540 Symbol bestSoFar = typeNotFound;
2541 Symbol sym;
2542 if (kind.contains(KindSelector.VAL)) {
2543 sym = findField(env, site, name, site.tsym);
2544 if (sym.exists()) return sym;
2545 else bestSoFar = bestOf(bestSoFar, sym);
2546 }
2547
2548 if (kind.contains(KindSelector.TYP)) {
2549 sym = findMemberType(env, site, name, site.tsym);
2550 if (sym.exists()) return sym;
2551 else bestSoFar = bestOf(bestSoFar, sym);
2552 }
2553 return bestSoFar;
2554 }
2555
2556 private Symbol checkRestrictedType(DiagnosticPosition pos, Symbol bestSoFar, Name name) {
2557 if (bestSoFar.kind == TYP || bestSoFar.kind == ABSENT_TYP) {
2558 if (allowLocalVariableTypeInference && name.equals(names.var)) {
2559 bestSoFar = new BadRestrictedTypeError(names.var);
2560 } else if (name.equals(names.yield)) {
2561 if (allowYieldStatement) {
2562 bestSoFar = new BadRestrictedTypeError(names.yield);
2563 } else if (pos != null) {
2564 log.warning(pos, Warnings.IllegalRefToRestrictedType(names.yield));
2565 }
2566 }
2567 }
2568 return bestSoFar;
2569 }
2570
2571 /* ***************************************************************************
2572 * Access checking
2573 * The following methods convert ResolveErrors to ErrorSymbols, issuing
2574 * an error message in the process
2575 ****************************************************************************/
2576
2577 /** If `sym' is a bad symbol: report error and return errSymbol
2578 * else pass through unchanged,
2579 * additional arguments duplicate what has been used in trying to find the
2580 * symbol {@literal (--> flyweight pattern)}. This improves performance since we
2581 * expect misses to happen frequently.
2582 *
2583 * @param sym The symbol that was found, or a ResolveError.
2584 * @param pos The position to use for error reporting.
2585 * @param location The symbol the served as a context for this lookup
2586 * @param site The original type from where the selection took place.
2587 * @param name The symbol's name.
2588 * @param qualified Did we get here through a qualified expression resolution?
2589 * @param argtypes The invocation's value arguments,
2590 * if we looked for a method.
2591 * @param typeargtypes The invocation's type arguments,
2592 * if we looked for a method.
2593 * @param logResolveHelper helper class used to log resolve errors
2594 */
2595 Symbol accessInternal(Symbol sym,
2596 DiagnosticPosition pos,
2597 Symbol location,
2598 Type site,
2599 Name name,
2600 boolean qualified,
2601 List<Type> argtypes,
2602 List<Type> typeargtypes,
2603 LogResolveHelper logResolveHelper) {
2604 if (sym.kind.isResolutionError()) {
2605 ResolveError errSym = (ResolveError)sym.baseSymbol();
2606 sym = errSym.access(name, qualified ? site.tsym : syms.noSymbol);
2607 argtypes = logResolveHelper.getArgumentTypes(errSym, sym, name, argtypes);
2608 if (logResolveHelper.resolveDiagnosticNeeded(site, argtypes, typeargtypes)) {
2609 logResolveError(errSym, pos, location, site, name, argtypes, typeargtypes);
2610 }
2611 }
2612 return sym;
2613 }
2614
2615 /**
2616 * Variant of the generalized access routine, to be used for generating method
2617 * resolution diagnostics
2618 */
2619 Symbol accessMethod(Symbol sym,
2620 DiagnosticPosition pos,
2621 Symbol location,
2622 Type site,
2623 Name name,
2624 boolean qualified,
2625 List<Type> argtypes,
2626 List<Type> typeargtypes) {
2627 return accessInternal(sym, pos, location, site, name, qualified, argtypes, typeargtypes, methodLogResolveHelper);
2628 }
2629
2630 /** Same as original accessMethod(), but without location.
2631 */
2632 Symbol accessMethod(Symbol sym,
2633 DiagnosticPosition pos,
2634 Type site,
2635 Name name,
2636 boolean qualified,
2637 List<Type> argtypes,
2638 List<Type> typeargtypes) {
2639 return accessMethod(sym, pos, site.tsym, site, name, qualified, argtypes, typeargtypes);
2640 }
2641
2642 /**
2643 * Variant of the generalized access routine, to be used for generating variable,
2644 * type resolution diagnostics
2645 */
2646 Symbol accessBase(Symbol sym,
2647 DiagnosticPosition pos,
2648 Symbol location,
2649 Type site,
2650 Name name,
2651 boolean qualified) {
2652 return accessInternal(sym, pos, location, site, name, qualified, List.nil(), null, basicLogResolveHelper);
2653 }
2654
2655 /** Same as original accessBase(), but without location.
2656 */
2657 Symbol accessBase(Symbol sym,
2658 DiagnosticPosition pos,
2659 Type site,
2660 Name name,
2661 boolean qualified) {
2662 return accessBase(sym, pos, site.tsym, site, name, qualified);
2663 }
2664
2665 interface LogResolveHelper {
2666 boolean resolveDiagnosticNeeded(Type site, List<Type> argtypes, List<Type> typeargtypes);
2667 List<Type> getArgumentTypes(ResolveError errSym, Symbol accessedSym, Name name, List<Type> argtypes);
2668 }
2669
2670 LogResolveHelper basicLogResolveHelper = new LogResolveHelper() {
2671 public boolean resolveDiagnosticNeeded(Type site, List<Type> argtypes, List<Type> typeargtypes) {
2672 return !site.isErroneous();
2673 }
2674 public List<Type> getArgumentTypes(ResolveError errSym, Symbol accessedSym, Name name, List<Type> argtypes) {
2675 return argtypes;
2676 }
2677 };
2678
2679 LogResolveHelper silentLogResolveHelper = new LogResolveHelper() {
2680 public boolean resolveDiagnosticNeeded(Type site, List<Type> argtypes, List<Type> typeargtypes) {
2681 return false;
2682 }
2683 public List<Type> getArgumentTypes(ResolveError errSym, Symbol accessedSym, Name name, List<Type> argtypes) {
2684 return argtypes;
2685 }
2686 };
2687
2688 LogResolveHelper methodLogResolveHelper = new LogResolveHelper() {
2689 public boolean resolveDiagnosticNeeded(Type site, List<Type> argtypes, List<Type> typeargtypes) {
2690 return !site.isErroneous() &&
2691 !Type.isErroneous(argtypes) &&
2692 (typeargtypes == null || !Type.isErroneous(typeargtypes));
2693 }
2694 public List<Type> getArgumentTypes(ResolveError errSym, Symbol accessedSym, Name name, List<Type> argtypes) {
2695 return argtypes.map(new ResolveDeferredRecoveryMap(AttrMode.SPECULATIVE, accessedSym, currentResolutionContext.step));
2696 }
2697 };
2698
2699 class ResolveDeferredRecoveryMap extends DeferredAttr.RecoveryDeferredTypeMap {
2700
2701 public ResolveDeferredRecoveryMap(AttrMode mode, Symbol msym, MethodResolutionPhase step) {
2702 deferredAttr.super(mode, msym, step);
2703 }
2704
2705 @Override
2706 protected Type typeOf(DeferredType dt, Type pt) {
2707 Type res = super.typeOf(dt, pt);
2708 if (!res.isErroneous()) {
2709 switch (TreeInfo.skipParens(dt.tree).getTag()) {
2710 case LAMBDA:
2711 case REFERENCE:
2712 return dt;
2713 case CONDEXPR:
2714 return res == Type.recoveryType ?
2715 dt : res;
2716 }
2717 }
2718 return res;
2719 }
2720 }
2721
2722 /** Check that sym is not an abstract method.
2723 */
2724 void checkNonAbstract(DiagnosticPosition pos, Symbol sym) {
2725 if ((sym.flags() & ABSTRACT) != 0 && (sym.flags() & DEFAULT) == 0)
2726 log.error(pos,
2727 Errors.AbstractCantBeAccessedDirectly(kindName(sym),sym, sym.location()));
2728 }
2729
2730 /* ***************************************************************************
2731 * Name resolution
2732 * Naming conventions are as for symbol lookup
2733 * Unlike the find... methods these methods will report access errors
2734 ****************************************************************************/
2735
2736 /** Resolve an unqualified (non-method) identifier.
2737 * @param pos The position to use for error reporting.
2738 * @param env The environment current at the identifier use.
2739 * @param name The identifier's name.
2740 * @param kind The set of admissible symbol kinds for the identifier.
2741 */
2742 Symbol resolveIdent(DiagnosticPosition pos, Env<AttrContext> env,
2743 Name name, KindSelector kind) {
2744 return accessBase(
2745 findIdent(pos, env, name, kind),
2746 pos, env.enclClass.sym.type, name, false);
2747 }
2748
2749 /** Resolve an unqualified method identifier.
2750 * @param pos The position to use for error reporting.
2751 * @param env The environment current at the method invocation.
2752 * @param name The identifier's name.
2753 * @param argtypes The types of the invocation's value arguments.
2754 * @param typeargtypes The types of the invocation's type arguments.
2755 */
2756 Symbol resolveMethod(DiagnosticPosition pos,
2757 Env<AttrContext> env,
2758 Name name,
2759 List<Type> argtypes,
2760 List<Type> typeargtypes) {
2761 return lookupMethod(env, pos, env.enclClass.sym, resolveMethodCheck,
2762 new BasicLookupHelper(name, env.enclClass.sym.type, argtypes, typeargtypes) {
2763 @Override
2764 Symbol lookup(Env<AttrContext> env, MethodResolutionPhase phase) {
2765 return findFun(env, name, argtypes, typeargtypes,
2766 phase.isBoxingRequired(),
2767 phase.isVarargsRequired());
2768 }});
2769 }
2770
2771 /** Resolve a qualified method identifier
2772 * @param pos The position to use for error reporting.
2773 * @param env The environment current at the method invocation.
2774 * @param site The type of the qualifying expression, in which
2775 * identifier is searched.
2776 * @param name The identifier's name.
2777 * @param argtypes The types of the invocation's value arguments.
2778 * @param typeargtypes The types of the invocation's type arguments.
2779 */
2780 Symbol resolveQualifiedMethod(DiagnosticPosition pos, Env<AttrContext> env,
2781 Type site, Name name, List<Type> argtypes,
2782 List<Type> typeargtypes) {
2783 return resolveQualifiedMethod(pos, env, site.tsym, site, name, argtypes, typeargtypes);
2784 }
2785 Symbol resolveQualifiedMethod(DiagnosticPosition pos, Env<AttrContext> env,
2786 Symbol location, Type site, Name name, List<Type> argtypes,
2787 List<Type> typeargtypes) {
2788 return resolveQualifiedMethod(new MethodResolutionContext(), pos, env, location, site, name, argtypes, typeargtypes);
2789 }
2790 private Symbol resolveQualifiedMethod(MethodResolutionContext resolveContext,
2791 DiagnosticPosition pos, Env<AttrContext> env,
2792 Symbol location, Type site, Name name, List<Type> argtypes,
2793 List<Type> typeargtypes) {
2794 return lookupMethod(env, pos, location, resolveContext, new BasicLookupHelper(name, site, argtypes, typeargtypes) {
2795 @Override
2796 Symbol lookup(Env<AttrContext> env, MethodResolutionPhase phase) {
2797 return findMethod(env, site, name, argtypes, typeargtypes,
2798 phase.isBoxingRequired(),
2799 phase.isVarargsRequired());
2800 }
2801 @Override
2802 Symbol access(Env<AttrContext> env, DiagnosticPosition pos, Symbol location, Symbol sym) {
2803 if (sym.kind.isResolutionError()) {
2804 sym = super.access(env, pos, location, sym);
2805 } else {
2806 MethodSymbol msym = (MethodSymbol)sym;
2807 if ((msym.flags() & SIGNATURE_POLYMORPHIC) != 0) {
2808 env.info.pendingResolutionPhase = BASIC;
2809 return findPolymorphicSignatureInstance(env, sym, argtypes);
2810 }
2811 }
2812 return sym;
2813 }
2814 });
2815 }
2816
2817 /** Find or create an implicit method of exactly the given type (after erasure).
2818 * Searches in a side table, not the main scope of the site.
2819 * This emulates the lookup process required by JSR 292 in JVM.
2820 * @param env Attribution environment
2821 * @param spMethod signature polymorphic method - i.e. MH.invokeExact
2822 * @param argtypes The required argument types
2823 */
2824 Symbol findPolymorphicSignatureInstance(Env<AttrContext> env,
2825 final Symbol spMethod,
2826 List<Type> argtypes) {
2827 Type mtype = infer.instantiatePolymorphicSignatureInstance(env,
2828 (MethodSymbol)spMethod, currentResolutionContext, argtypes);
2829 return findPolymorphicSignatureInstance(spMethod, mtype);
2830 }
2831
2832 Symbol findPolymorphicSignatureInstance(final Symbol spMethod,
2833 Type mtype) {
2834 for (Symbol sym : polymorphicSignatureScope.getSymbolsByName(spMethod.name)) {
2835 // Check that there is already a method symbol for the method
2836 // type and owner
2837 if (types.isSameType(mtype, sym.type) &&
2838 spMethod.owner == sym.owner) {
2839 return sym;
2840 }
2841 }
2842
2843 Type spReturnType = spMethod.asType().getReturnType();
2844 if (types.isSameType(spReturnType, syms.objectType)) {
2845 // Polymorphic return, pass through mtype
2846 } else if (!types.isSameType(spReturnType, mtype.getReturnType())) {
2847 // Retain the sig poly method's return type, which differs from that of mtype
2848 // Will result in an incompatible return type error
2849 mtype = new MethodType(mtype.getParameterTypes(),
2850 spReturnType,
2851 mtype.getThrownTypes(),
2852 syms.methodClass);
2853 }
2854
2855 // Create the desired method
2856 // Retain static modifier is to support invocations to
2857 // MethodHandle.linkTo* methods
2858 long flags = ABSTRACT | HYPOTHETICAL |
2859 spMethod.flags() & (Flags.AccessFlags | Flags.STATIC);
2860 Symbol msym = new MethodSymbol(flags, spMethod.name, mtype, spMethod.owner) {
2861 @Override
2862 public Symbol baseSymbol() {
2863 return spMethod;
2864 }
2865 };
2866 if (!mtype.isErroneous()) { // Cache only if kosher.
2867 polymorphicSignatureScope.enter(msym);
2868 }
2869 return msym;
2870 }
2871
2872 /** Resolve a qualified method identifier, throw a fatal error if not
2873 * found.
2874 * @param pos The position to use for error reporting.
2875 * @param env The environment current at the method invocation.
2876 * @param site The type of the qualifying expression, in which
2877 * identifier is searched.
2878 * @param name The identifier's name.
2879 * @param argtypes The types of the invocation's value arguments.
2880 * @param typeargtypes The types of the invocation's type arguments.
2881 */
2882 public MethodSymbol resolveInternalMethod(DiagnosticPosition pos, Env<AttrContext> env,
2883 Type site, Name name,
2884 List<Type> argtypes,
2885 List<Type> typeargtypes) {
2886 MethodResolutionContext resolveContext = new MethodResolutionContext();
2887 resolveContext.internalResolution = true;
2888 Symbol sym = resolveQualifiedMethod(resolveContext, pos, env, site.tsym,
2889 site, name, argtypes, typeargtypes);
2890 if (sym.kind == MTH) return (MethodSymbol)sym;
2891 else throw new FatalError(
2892 diags.fragment(Fragments.FatalErrCantLocateMeth(name)));
2893 }
2894
2895 /** Resolve constructor.
2896 * @param pos The position to use for error reporting.
2897 * @param env The environment current at the constructor invocation.
2898 * @param site The type of class for which a constructor is searched.
2899 * @param argtypes The types of the constructor invocation's value
2900 * arguments.
2901 * @param typeargtypes The types of the constructor invocation's type
2902 * arguments.
2903 */
2904 Symbol resolveConstructor(DiagnosticPosition pos,
2905 Env<AttrContext> env,
2906 Type site,
2907 List<Type> argtypes,
2908 List<Type> typeargtypes) {
2909 return resolveConstructor(new MethodResolutionContext(), pos, env, site, argtypes, typeargtypes);
2910 }
2911
2912 private Symbol resolveConstructor(MethodResolutionContext resolveContext,
2913 final DiagnosticPosition pos,
2914 Env<AttrContext> env,
2915 Type site,
2916 List<Type> argtypes,
2917 List<Type> typeargtypes) {
2918 return lookupMethod(env, pos, site.tsym, resolveContext, new BasicLookupHelper(names.init, site, argtypes, typeargtypes) {
2919 @Override
2920 Symbol lookup(Env<AttrContext> env, MethodResolutionPhase phase) {
2921 return findConstructor(pos, env, site, argtypes, typeargtypes,
2922 phase.isBoxingRequired(),
2923 phase.isVarargsRequired());
2924 }
2925 });
2926 }
2927
2928 /** Resolve a constructor, throw a fatal error if not found.
2929 * @param pos The position to use for error reporting.
2930 * @param env The environment current at the method invocation.
2931 * @param site The type to be constructed.
2932 * @param argtypes The types of the invocation's value arguments.
2933 * @param typeargtypes The types of the invocation's type arguments.
2934 */
2935 public MethodSymbol resolveInternalConstructor(DiagnosticPosition pos, Env<AttrContext> env,
2936 Type site,
2937 List<Type> argtypes,
2938 List<Type> typeargtypes) {
2939 MethodResolutionContext resolveContext = new MethodResolutionContext();
2940 resolveContext.internalResolution = true;
2941 Symbol sym = resolveConstructor(resolveContext, pos, env, site, argtypes, typeargtypes);
2942 if (sym.kind == MTH) return (MethodSymbol)sym;
2943 else throw new FatalError(
2944 diags.fragment(Fragments.FatalErrCantLocateCtor(site)));
2945 }
2946
2947 Symbol findConstructor(DiagnosticPosition pos, Env<AttrContext> env,
2948 Type site, List<Type> argtypes,
2949 List<Type> typeargtypes,
2950 boolean allowBoxing,
2951 boolean useVarargs) {
2952 Symbol sym = findMethod(env, site,
2953 names.init, argtypes,
2954 typeargtypes, allowBoxing,
2955 useVarargs);
2956 chk.checkDeprecated(pos, env.info.scope.owner, sym);
2957 chk.checkPreview(pos, env.info.scope.owner, sym);
2958 return sym;
2959 }
2960
2961 /** Resolve constructor using diamond inference.
2962 * @param pos The position to use for error reporting.
2963 * @param env The environment current at the constructor invocation.
2964 * @param site The type of class for which a constructor is searched.
2965 * The scope of this class has been touched in attribution.
2966 * @param argtypes The types of the constructor invocation's value
2967 * arguments.
2968 * @param typeargtypes The types of the constructor invocation's type
2969 * arguments.
2970 */
2971 Symbol resolveDiamond(DiagnosticPosition pos,
2972 Env<AttrContext> env,
2973 Type site,
2974 List<Type> argtypes,
2975 List<Type> typeargtypes) {
2976 return lookupMethod(env, pos, site.tsym, resolveMethodCheck,
2977 new BasicLookupHelper(names.init, site, argtypes, typeargtypes) {
2978 @Override
2979 Symbol lookup(Env<AttrContext> env, MethodResolutionPhase phase) {
2980 return findDiamond(pos, env, site, argtypes, typeargtypes,
2981 phase.isBoxingRequired(),
2982 phase.isVarargsRequired());
2983 }
2984 @Override
2985 Symbol access(Env<AttrContext> env, DiagnosticPosition pos, Symbol location, Symbol sym) {
2986 if (sym.kind.isResolutionError()) {
2987 if (sym.kind != WRONG_MTH &&
2988 sym.kind != WRONG_MTHS) {
2989 sym = super.access(env, pos, location, sym);
2990 } else {
2991 sym = new DiamondError(sym, currentResolutionContext);
2992 sym = accessMethod(sym, pos, site, names.init, true, argtypes, typeargtypes);
2993 env.info.pendingResolutionPhase = currentResolutionContext.step;
2994 }
2995 }
2996 return sym;
2997 }});
2998 }
2999
3000 /** Find the constructor using diamond inference and do some checks(deprecated and preview).
3001 * @param pos The position to use for error reporting.
3002 * @param env The environment current at the constructor invocation.
3003 * @param site The type of class for which a constructor is searched.
3004 * The scope of this class has been touched in attribution.
3005 * @param argtypes The types of the constructor invocation's value arguments.
3006 * @param typeargtypes The types of the constructor invocation's type arguments.
3007 * @param allowBoxing Allow boxing conversions of arguments.
3008 * @param useVarargs Box trailing arguments into an array for varargs.
3009 */
3010 private Symbol findDiamond(DiagnosticPosition pos,
3011 Env<AttrContext> env,
3012 Type site,
3013 List<Type> argtypes,
3014 List<Type> typeargtypes,
3015 boolean allowBoxing,
3016 boolean useVarargs) {
3017 Symbol sym = findDiamond(env, site, argtypes, typeargtypes, allowBoxing, useVarargs);
3018 chk.checkDeprecated(pos, env.info.scope.owner, sym);
3019 chk.checkPreview(pos, env.info.scope.owner, sym);
3020 return sym;
3021 }
3022
3023 /** This method scans all the constructor symbol in a given class scope -
3024 * assuming that the original scope contains a constructor of the kind:
3025 * {@code Foo(X x, Y y)}, where X,Y are class type-variables declared in Foo,
3026 * a method check is executed against the modified constructor type:
3027 * {@code <X,Y>Foo<X,Y>(X x, Y y)}. This is crucial in order to enable diamond
3028 * inference. The inferred return type of the synthetic constructor IS
3029 * the inferred type for the diamond operator.
3030 */
3031 private Symbol findDiamond(Env<AttrContext> env,
3032 Type site,
3033 List<Type> argtypes,
3034 List<Type> typeargtypes,
3035 boolean allowBoxing,
3036 boolean useVarargs) {
3037 Symbol bestSoFar = methodNotFound;
3038 TypeSymbol tsym = site.tsym.isInterface() ? syms.objectType.tsym : site.tsym;
3039 for (final Symbol sym : tsym.members().getSymbolsByName(names.init)) {
3040 //- System.out.println(" e " + e.sym);
3041 if (sym.kind == MTH &&
3042 (sym.flags_field & SYNTHETIC) == 0) {
3043 List<Type> oldParams = sym.type.hasTag(FORALL) ?
3044 ((ForAll)sym.type).tvars :
3045 List.nil();
3046 Type constrType = new ForAll(site.tsym.type.getTypeArguments().appendList(oldParams),
3047 types.createMethodTypeWithReturn(sym.type.asMethodType(), site));
3048 MethodSymbol newConstr = new MethodSymbol(sym.flags(), names.init, constrType, site.tsym) {
3049 @Override
3050 public Symbol baseSymbol() {
3051 return sym;
3052 }
3053 };
3054 bestSoFar = selectBest(env, site, argtypes, typeargtypes,
3055 newConstr,
3056 bestSoFar,
3057 allowBoxing,
3058 useVarargs);
3059 }
3060 }
3061 return bestSoFar;
3062 }
3063
3064 Symbol getMemberReference(DiagnosticPosition pos,
3065 Env<AttrContext> env,
3066 JCMemberReference referenceTree,
3067 Type site,
3068 Name name) {
3069
3070 site = types.capture(site);
3071
3072 ReferenceLookupHelper lookupHelper = makeReferenceLookupHelper(
3073 referenceTree, site, name, List.nil(), null, VARARITY);
3074
3075 Env<AttrContext> newEnv = env.dup(env.tree, env.info.dup());
3076 Symbol sym = lookupMethod(newEnv, env.tree.pos(), site.tsym,
3077 nilMethodCheck, lookupHelper);
3078
3079 env.info.pendingResolutionPhase = newEnv.info.pendingResolutionPhase;
3080
3081 return sym;
3082 }
3083
3084 ReferenceLookupHelper makeReferenceLookupHelper(JCMemberReference referenceTree,
3085 Type site,
3086 Name name,
3087 List<Type> argtypes,
3088 List<Type> typeargtypes,
3089 MethodResolutionPhase maxPhase) {
3090 if (!name.equals(names.init)) {
3091 //method reference
3092 return new MethodReferenceLookupHelper(referenceTree, name, site, argtypes, typeargtypes, maxPhase);
3093 } else if (site.hasTag(ARRAY)) {
3094 //array constructor reference
3095 return new ArrayConstructorReferenceLookupHelper(referenceTree, site, argtypes, typeargtypes, maxPhase);
3096 } else {
3097 //class constructor reference
3098 return new ConstructorReferenceLookupHelper(referenceTree, site, argtypes, typeargtypes, maxPhase);
3099 }
3100 }
3101
3102 /**
3103 * Resolution of member references is typically done as a single
3104 * overload resolution step, where the argument types A are inferred from
3105 * the target functional descriptor.
3106 *
3107 * If the member reference is a method reference with a type qualifier,
3108 * a two-step lookup process is performed. The first step uses the
3109 * expected argument list A, while the second step discards the first
3110 * type from A (which is treated as a receiver type).
3111 *
3112 * There are two cases in which inference is performed: (i) if the member
3113 * reference is a constructor reference and the qualifier type is raw - in
3114 * which case diamond inference is used to infer a parameterization for the
3115 * type qualifier; (ii) if the member reference is an unbound reference
3116 * where the type qualifier is raw - in that case, during the unbound lookup
3117 * the receiver argument type is used to infer an instantiation for the raw
3118 * qualifier type.
3119 *
3120 * When a multi-step resolution process is exploited, the process of picking
3121 * the resulting symbol is delegated to an helper class {@link com.sun.tools.javac.comp.Resolve.ReferenceChooser}.
3122 *
3123 * This routine returns a pair (T,S), where S is the member reference symbol,
3124 * and T is the type of the class in which S is defined. This is necessary as
3125 * the type T might be dynamically inferred (i.e. if constructor reference
3126 * has a raw qualifier).
3127 */
3128 Pair<Symbol, ReferenceLookupHelper> resolveMemberReference(Env<AttrContext> env,
3129 JCMemberReference referenceTree,
3130 Type site,
3131 Name name,
3132 List<Type> argtypes,
3133 List<Type> typeargtypes,
3134 Type descriptor,
3135 MethodCheck methodCheck,
3136 InferenceContext inferenceContext,
3137 ReferenceChooser referenceChooser) {
3138
3139 //step 1 - bound lookup
3140 ReferenceLookupHelper boundLookupHelper = makeReferenceLookupHelper(
3141 referenceTree, site, name, argtypes, typeargtypes, VARARITY);
3142 Env<AttrContext> boundEnv = env.dup(env.tree, env.info.dup());
3143 MethodResolutionContext boundSearchResolveContext = new MethodResolutionContext();
3144 boundSearchResolveContext.methodCheck = methodCheck;
3145 Symbol boundSym = lookupMethod(boundEnv, env.tree.pos(),
3146 site.tsym, boundSearchResolveContext, boundLookupHelper);
3147 boolean isStaticSelector = TreeInfo.isStaticSelector(referenceTree.expr, names);
3148 ReferenceLookupResult boundRes = new ReferenceLookupResult(boundSym, boundSearchResolveContext, isStaticSelector);
3149 if (dumpMethodReferenceSearchResults) {
3150 dumpMethodReferenceSearchResults(referenceTree, boundSearchResolveContext, boundSym, true);
3151 }
3152
3153 //step 2 - unbound lookup
3154 Symbol unboundSym = methodNotFound;
3155 Env<AttrContext> unboundEnv = env.dup(env.tree, env.info.dup());
3156 ReferenceLookupHelper unboundLookupHelper = boundLookupHelper.unboundLookup(inferenceContext);
3157 ReferenceLookupResult unboundRes = referenceNotFound;
3158 if (unboundLookupHelper != null) {
3159 MethodResolutionContext unboundSearchResolveContext =
3160 new MethodResolutionContext();
3161 unboundSearchResolveContext.methodCheck = methodCheck;
3162 unboundSym = lookupMethod(unboundEnv, env.tree.pos(),
3163 site.tsym, unboundSearchResolveContext, unboundLookupHelper);
3164 unboundRes = new ReferenceLookupResult(unboundSym, unboundSearchResolveContext, isStaticSelector);
3165 if (dumpMethodReferenceSearchResults) {
3166 dumpMethodReferenceSearchResults(referenceTree, unboundSearchResolveContext, unboundSym, false);
3167 }
3168 }
3169
3170 //merge results
3171 Pair<Symbol, ReferenceLookupHelper> res;
3172 ReferenceLookupResult bestRes = referenceChooser.result(boundRes, unboundRes);
3173 res = new Pair<>(bestRes.sym,
3174 bestRes == unboundRes ? unboundLookupHelper : boundLookupHelper);
3175 env.info.pendingResolutionPhase = bestRes == unboundRes ?
3176 unboundEnv.info.pendingResolutionPhase :
3177 boundEnv.info.pendingResolutionPhase;
3178
3179 if (!res.fst.kind.isResolutionError()) {
3180 //handle sigpoly method references
3181 MethodSymbol msym = (MethodSymbol)res.fst;
3182 if ((msym.flags() & SIGNATURE_POLYMORPHIC) != 0) {
3183 env.info.pendingResolutionPhase = BASIC;
3184 res = new Pair<>(findPolymorphicSignatureInstance(msym, descriptor), res.snd);
3185 }
3186 }
3187
3188 return res;
3189 }
3190
3191 private void dumpMethodReferenceSearchResults(JCMemberReference referenceTree,
3192 MethodResolutionContext resolutionContext,
3193 Symbol bestSoFar,
3194 boolean bound) {
3195 ListBuffer<JCDiagnostic> subDiags = new ListBuffer<>();
3196 int pos = 0;
3197 int mostSpecificPos = -1;
3198 for (Candidate c : resolutionContext.candidates) {
3199 if (resolutionContext.step != c.step || !c.isApplicable()) {
3200 continue;
3201 } else {
3202 JCDiagnostic subDiag = null;
3203 if (c.sym.type.hasTag(FORALL)) {
3204 subDiag = diags.fragment(Fragments.PartialInstSig(c.mtype));
3205 }
3206
3207 String key = subDiag == null ?
3208 "applicable.method.found.2" :
3209 "applicable.method.found.3";
3210 subDiags.append(diags.fragment(key, pos,
3211 c.sym.isStatic() ? Fragments.Static : Fragments.NonStatic, c.sym, subDiag));
3212 if (c.sym == bestSoFar)
3213 mostSpecificPos = pos;
3214 pos++;
3215 }
3216 }
3217 JCDiagnostic main = diags.note(
3218 log.currentSource(),
3219 referenceTree,
3220 "method.ref.search.results.multi",
3221 bound ? Fragments.Bound : Fragments.Unbound,
3222 referenceTree.toString(), mostSpecificPos);
3223 JCDiagnostic d = new JCDiagnostic.MultilineDiagnostic(main, subDiags.toList());
3224 log.report(d);
3225 }
3226
3227 /**
3228 * This class is used to represent a method reference lookup result. It keeps track of two
3229 * things: (i) the symbol found during a method reference lookup and (ii) the static kind
3230 * of the lookup (see {@link com.sun.tools.javac.comp.Resolve.ReferenceLookupResult.StaticKind}).
3231 */
3232 static class ReferenceLookupResult {
3233
3234 /**
3235 * Static kind associated with a method reference lookup. Erroneous lookups end up with
3236 * the UNDEFINED kind; successful lookups will end up with either STATIC, NON_STATIC,
3237 * depending on whether all applicable candidates are static or non-static methods,
3238 * respectively. If a successful lookup has both static and non-static applicable methods,
3239 * its kind is set to BOTH.
3240 */
3241 enum StaticKind {
3242 STATIC,
3243 NON_STATIC,
3244 BOTH,
3245 UNDEFINED;
3246
3247 /**
3248 * Retrieve the static kind associated with a given (method) symbol.
3249 */
3250 static StaticKind from(Symbol s) {
3251 return s.isStatic() ?
3252 STATIC : NON_STATIC;
3253 }
3254
3255 /**
3256 * Merge two static kinds together.
3257 */
3258 static StaticKind reduce(StaticKind sk1, StaticKind sk2) {
3259 if (sk1 == UNDEFINED) {
3260 return sk2;
3261 } else if (sk2 == UNDEFINED) {
3262 return sk1;
3263 } else {
3264 return sk1 == sk2 ? sk1 : BOTH;
3265 }
3266 }
3267 }
3268
3269 /** The static kind. */
3270 StaticKind staticKind;
3271
3272 /** The lookup result. */
3273 Symbol sym;
3274
3275 ReferenceLookupResult(Symbol sym, MethodResolutionContext resolutionContext, boolean isStaticSelector) {
3276 this(sym, staticKind(sym, resolutionContext, isStaticSelector));
3277 }
3278
3279 private ReferenceLookupResult(Symbol sym, StaticKind staticKind) {
3280 this.staticKind = staticKind;
3281 this.sym = sym;
3282 }
3283
3284 private static StaticKind staticKind(Symbol sym, MethodResolutionContext resolutionContext, boolean isStaticSelector) {
3285 if (sym.kind == MTH && !isStaticSelector) {
3286 return StaticKind.from(sym);
3287 } else if (sym.kind == MTH || sym.kind == AMBIGUOUS) {
3288 return resolutionContext.candidates.stream()
3289 .filter(c -> c.isApplicable() && c.step == resolutionContext.step)
3290 .map(c -> StaticKind.from(c.sym))
3291 .reduce(StaticKind::reduce)
3292 .orElse(StaticKind.UNDEFINED);
3293 } else {
3294 return StaticKind.UNDEFINED;
3295 }
3296 }
3297
3298 /**
3299 * Does this result corresponds to a successful lookup (i.e. one where a method has been found?)
3300 */
3301 boolean isSuccess() {
3302 return staticKind != StaticKind.UNDEFINED;
3303 }
3304
3305 /**
3306 * Does this result have given static kind?
3307 */
3308 boolean hasKind(StaticKind sk) {
3309 return this.staticKind == sk;
3310 }
3311
3312 /**
3313 * Error recovery helper: can this lookup result be ignored (for the purpose of returning
3314 * some 'better' result) ?
3315 */
3316 boolean canIgnore() {
3317 switch (sym.kind) {
3318 case ABSENT_MTH:
3319 return true;
3320 case WRONG_MTH:
3321 InapplicableSymbolError errSym =
3322 (InapplicableSymbolError)sym.baseSymbol();
3323 return new Template(MethodCheckDiag.ARITY_MISMATCH.regex())
3324 .matches(errSym.errCandidate().snd);
3325 case WRONG_MTHS:
3326 InapplicableSymbolsError errSyms =
3327 (InapplicableSymbolsError)sym.baseSymbol();
3328 return errSyms.filterCandidates(errSyms.mapCandidates()).isEmpty();
3329 default:
3330 return false;
3331 }
3332 }
3333
3334 static ReferenceLookupResult error(Symbol sym) {
3335 return new ReferenceLookupResult(sym, StaticKind.UNDEFINED);
3336 }
3337 }
3338
3339 /**
3340 * This abstract class embodies the logic that converts one (bound lookup) or two (unbound lookup)
3341 * {@code ReferenceLookupResult} objects into a {@code Symbol}, which is then regarded as the
3342 * result of method reference resolution.
3343 */
3344 abstract class ReferenceChooser {
3345 /**
3346 * Generate a result from a pair of lookup result objects. This method delegates to the
3347 * appropriate result generation routine.
3348 */
3349 ReferenceLookupResult result(ReferenceLookupResult boundRes, ReferenceLookupResult unboundRes) {
3350 return unboundRes != referenceNotFound ?
3351 unboundResult(boundRes, unboundRes) :
3352 boundResult(boundRes);
3353 }
3354
3355 /**
3356 * Generate a symbol from a given bound lookup result.
3357 */
3358 abstract ReferenceLookupResult boundResult(ReferenceLookupResult boundRes);
3359
3360 /**
3361 * Generate a symbol from a pair of bound/unbound lookup results.
3362 */
3363 abstract ReferenceLookupResult unboundResult(ReferenceLookupResult boundRes, ReferenceLookupResult unboundRes);
3364 }
3365
3366 /**
3367 * This chooser implements the selection strategy used during a full lookup; this logic
3368 * is described in JLS SE 8 (15.3.2).
3369 */
3370 ReferenceChooser basicReferenceChooser = new ReferenceChooser() {
3371
3372 @Override
3373 ReferenceLookupResult boundResult(ReferenceLookupResult boundRes) {
3374 return !boundRes.isSuccess() || boundRes.hasKind(StaticKind.NON_STATIC) ?
3375 boundRes : //the search produces a non-static method
3376 ReferenceLookupResult.error(new BadMethodReferenceError(boundRes.sym, false));
3377 }
3378
3379 @Override
3380 ReferenceLookupResult unboundResult(ReferenceLookupResult boundRes, ReferenceLookupResult unboundRes) {
3381 if (boundRes.isSuccess() && boundRes.sym.isStatic() &&
3382 (!unboundRes.isSuccess() || unboundRes.hasKind(StaticKind.STATIC))) {
3383 //the first search produces a static method and no non-static method is applicable
3384 //during the second search
3385 return boundRes;
3386 } else if (unboundRes.isSuccess() && !unboundRes.sym.isStatic() &&
3387 (!boundRes.isSuccess() || boundRes.hasKind(StaticKind.NON_STATIC))) {
3388 //the second search produces a non-static method and no static method is applicable
3389 //during the first search
3390 return unboundRes;
3391 } else if (boundRes.isSuccess() && unboundRes.isSuccess()) {
3392 //both searches produce some result; ambiguity (error recovery)
3393 return ReferenceLookupResult.error(ambiguityError(boundRes.sym, unboundRes.sym));
3394 } else if (boundRes.isSuccess() || unboundRes.isSuccess()) {
3395 //Both searches failed to produce a result with correct staticness (i.e. first search
3396 //produces an non-static method). Alternatively, a given search produced a result
3397 //with the right staticness, but the other search has applicable methods with wrong
3398 //staticness (error recovery)
3399 return ReferenceLookupResult.error(new BadMethodReferenceError(boundRes.isSuccess() ?
3400 boundRes.sym : unboundRes.sym, true));
3401 } else {
3402 //both searches fail to produce a result - pick 'better' error using heuristics (error recovery)
3403 return (boundRes.canIgnore() && !unboundRes.canIgnore()) ?
3404 unboundRes : boundRes;
3405 }
3406 }
3407 };
3408
3409 /**
3410 * This chooser implements the selection strategy used during an arity-based lookup; this logic
3411 * is described in JLS SE 8 (15.12.2.1).
3412 */
3413 ReferenceChooser structuralReferenceChooser = new ReferenceChooser() {
3414
3415 @Override
3416 ReferenceLookupResult boundResult(ReferenceLookupResult boundRes) {
3417 return (!boundRes.isSuccess() || !boundRes.hasKind(StaticKind.STATIC)) ?
3418 boundRes : //the search has at least one applicable non-static method
3419 ReferenceLookupResult.error(new BadMethodReferenceError(boundRes.sym, false));
3420 }
3421
3422 @Override
3423 ReferenceLookupResult unboundResult(ReferenceLookupResult boundRes, ReferenceLookupResult unboundRes) {
3424 if (boundRes.isSuccess() && !boundRes.hasKind(StaticKind.NON_STATIC)) {
3425 //the first search has at least one applicable static method
3426 return boundRes;
3427 } else if (unboundRes.isSuccess() && !unboundRes.hasKind(StaticKind.STATIC)) {
3428 //the second search has at least one applicable non-static method
3429 return unboundRes;
3430 } else if (boundRes.isSuccess() || unboundRes.isSuccess()) {
3431 //either the first search produces a non-static method, or second search produces
3432 //a non-static method (error recovery)
3433 return ReferenceLookupResult.error(new BadMethodReferenceError(boundRes.isSuccess() ?
3434 boundRes.sym : unboundRes.sym, true));
3435 } else {
3436 //both searches fail to produce a result - pick 'better' error using heuristics (error recovery)
3437 return (boundRes.canIgnore() && !unboundRes.canIgnore()) ?
3438 unboundRes : boundRes;
3439 }
3440 }
3441 };
3442
3443 /**
3444 * Helper for defining custom method-like lookup logic; a lookup helper
3445 * provides hooks for (i) the actual lookup logic and (ii) accessing the
3446 * lookup result (this step might result in compiler diagnostics to be generated)
3447 */
3448 abstract class LookupHelper {
3449
3450 /** name of the symbol to lookup */
3451 Name name;
3452
3453 /** location in which the lookup takes place */
3454 Type site;
3455
3456 /** actual types used during the lookup */
3457 List<Type> argtypes;
3458
3459 /** type arguments used during the lookup */
3460 List<Type> typeargtypes;
3461
3462 /** Max overload resolution phase handled by this helper */
3463 MethodResolutionPhase maxPhase;
3464
3465 LookupHelper(Name name, Type site, List<Type> argtypes, List<Type> typeargtypes, MethodResolutionPhase maxPhase) {
3466 this.name = name;
3467 this.site = site;
3468 this.argtypes = argtypes;
3469 this.typeargtypes = typeargtypes;
3470 this.maxPhase = maxPhase;
3471 }
3472
3473 /**
3474 * Should lookup stop at given phase with given result
3475 */
3476 final boolean shouldStop(Symbol sym, MethodResolutionPhase phase) {
3477 return phase.ordinal() > maxPhase.ordinal() ||
3478 !sym.kind.isResolutionError() || sym.kind == AMBIGUOUS || sym.kind == STATICERR;
3479 }
3480
3481 /**
3482 * Search for a symbol under a given overload resolution phase - this method
3483 * is usually called several times, once per each overload resolution phase
3484 */
3485 abstract Symbol lookup(Env<AttrContext> env, MethodResolutionPhase phase);
3486
3487 /**
3488 * Dump overload resolution info
3489 */
3490 void debug(DiagnosticPosition pos, Symbol sym) {
3491 //do nothing
3492 }
3493
3494 /**
3495 * Validate the result of the lookup
3496 */
3497 abstract Symbol access(Env<AttrContext> env, DiagnosticPosition pos, Symbol location, Symbol sym);
3498 }
3499
3500 abstract class BasicLookupHelper extends LookupHelper {
3501
3502 BasicLookupHelper(Name name, Type site, List<Type> argtypes, List<Type> typeargtypes) {
3503 this(name, site, argtypes, typeargtypes, MethodResolutionPhase.VARARITY);
3504 }
3505
3506 BasicLookupHelper(Name name, Type site, List<Type> argtypes, List<Type> typeargtypes, MethodResolutionPhase maxPhase) {
3507 super(name, site, argtypes, typeargtypes, maxPhase);
3508 }
3509
3510 @Override
3511 Symbol access(Env<AttrContext> env, DiagnosticPosition pos, Symbol location, Symbol sym) {
3512 if (sym.kind.isResolutionError()) {
3513 //if nothing is found return the 'first' error
3514 sym = accessMethod(sym, pos, location, site, name, true, argtypes, typeargtypes);
3515 }
3516 return sym;
3517 }
3518
3519 @Override
3520 void debug(DiagnosticPosition pos, Symbol sym) {
3521 reportVerboseResolutionDiagnostic(pos, name, site, argtypes, typeargtypes, sym);
3522 }
3523 }
3524
3525 /**
3526 * Helper class for member reference lookup. A reference lookup helper
3527 * defines the basic logic for member reference lookup; a method gives
3528 * access to an 'unbound' helper used to perform an unbound member
3529 * reference lookup.
3530 */
3531 abstract class ReferenceLookupHelper extends LookupHelper {
3532
3533 /** The member reference tree */
3534 JCMemberReference referenceTree;
3535
3536 ReferenceLookupHelper(JCMemberReference referenceTree, Name name, Type site,
3537 List<Type> argtypes, List<Type> typeargtypes, MethodResolutionPhase maxPhase) {
3538 super(name, site, argtypes, typeargtypes, maxPhase);
3539 this.referenceTree = referenceTree;
3540 }
3541
3542 /**
3543 * Returns an unbound version of this lookup helper. By default, this
3544 * method returns an dummy lookup helper.
3545 */
3546 ReferenceLookupHelper unboundLookup(InferenceContext inferenceContext) {
3547 return null;
3548 }
3549
3550 /**
3551 * Get the kind of the member reference
3552 */
3553 abstract JCMemberReference.ReferenceKind referenceKind(Symbol sym);
3554
3555 Symbol access(Env<AttrContext> env, DiagnosticPosition pos, Symbol location, Symbol sym) {
3556 //skip error reporting
3557 return sym;
3558 }
3559 }
3560
3561 /**
3562 * Helper class for method reference lookup. The lookup logic is based
3563 * upon Resolve.findMethod; in certain cases, this helper class has a
3564 * corresponding unbound helper class (see UnboundMethodReferenceLookupHelper).
3565 * In such cases, non-static lookup results are thrown away.
3566 */
3567 class MethodReferenceLookupHelper extends ReferenceLookupHelper {
3568
3569 /** The original method reference lookup site. */
3570 Type originalSite;
3571
3572 MethodReferenceLookupHelper(JCMemberReference referenceTree, Name name, Type site,
3573 List<Type> argtypes, List<Type> typeargtypes, MethodResolutionPhase maxPhase) {
3574 super(referenceTree, name, types.skipTypeVars(site, true), argtypes, typeargtypes, maxPhase);
3575 this.originalSite = site;
3576 }
3577
3578 @Override
3579 final Symbol lookup(Env<AttrContext> env, MethodResolutionPhase phase) {
3580 return findMethod(env, site, name, argtypes, typeargtypes,
3581 phase.isBoxingRequired(), phase.isVarargsRequired());
3582 }
3583
3584 @Override
3585 ReferenceLookupHelper unboundLookup(InferenceContext inferenceContext) {
3586 if (TreeInfo.isStaticSelector(referenceTree.expr, names)) {
3587 if (argtypes.nonEmpty() &&
3588 (argtypes.head.hasTag(NONE) ||
3589 types.isSubtypeUnchecked(inferenceContext.asUndetVar(argtypes.head), originalSite))) {
3590 return new UnboundMethodReferenceLookupHelper(referenceTree, name,
3591 originalSite, argtypes, typeargtypes, maxPhase);
3592 } else {
3593 return new ReferenceLookupHelper(referenceTree, name, site, argtypes, typeargtypes, maxPhase) {
3594 @Override
3595 ReferenceLookupHelper unboundLookup(InferenceContext inferenceContext) {
3596 return this;
3597 }
3598
3599 @Override
3600 Symbol lookup(Env<AttrContext> env, MethodResolutionPhase phase) {
3601 return methodNotFound;
3602 }
3603
3604 @Override
3605 ReferenceKind referenceKind(Symbol sym) {
3606 Assert.error();
3607 return null;
3608 }
3609 };
3610 }
3611 } else {
3612 return super.unboundLookup(inferenceContext);
3613 }
3614 }
3615
3616 @Override
3617 ReferenceKind referenceKind(Symbol sym) {
3618 if (sym.isStatic()) {
3619 return ReferenceKind.STATIC;
3620 } else {
3621 Name selName = TreeInfo.name(referenceTree.getQualifierExpression());
3622 return selName != null && selName == names._super ?
3623 ReferenceKind.SUPER :
3624 ReferenceKind.BOUND;
3625 }
3626 }
3627
3628 @Override
3629 Symbol access(Env<AttrContext> env, DiagnosticPosition pos, Symbol location, Symbol sym) {
3630 if (originalSite.hasTag(TYPEVAR) && sym.kind == MTH) {
3631 sym = (sym.flags() & Flags.PRIVATE) != 0 ?
3632 new AccessError(env, site, sym) :
3633 sym;
3634 return accessBase(sym, pos, location, originalSite, name, true);
3635 } else {
3636 return super.access(env, pos, location, sym);
3637 }
3638 }
3639 }
3640
3641 /**
3642 * Helper class for unbound method reference lookup. Essentially the same
3643 * as the basic method reference lookup helper; main difference is that static
3644 * lookup results are thrown away. If qualifier type is raw, an attempt to
3645 * infer a parameterized type is made using the first actual argument (that
3646 * would otherwise be ignored during the lookup).
3647 */
3648 class UnboundMethodReferenceLookupHelper extends MethodReferenceLookupHelper {
3649
3650 UnboundMethodReferenceLookupHelper(JCMemberReference referenceTree, Name name, Type site,
3651 List<Type> argtypes, List<Type> typeargtypes, MethodResolutionPhase maxPhase) {
3652 super(referenceTree, name, site, argtypes.tail, typeargtypes, maxPhase);
3653 if (site.isRaw() && !argtypes.head.hasTag(NONE)) {
3654 Type asSuperSite = types.asSuper(argtypes.head, site.tsym);
3655 this.site = types.skipTypeVars(asSuperSite, true);
3656 }
3657 }
3658
3659 @Override
3660 ReferenceLookupHelper unboundLookup(InferenceContext inferenceContext) {
3661 return this;
3662 }
3663
3664 @Override
3665 ReferenceKind referenceKind(Symbol sym) {
3666 return ReferenceKind.UNBOUND;
3667 }
3668 }
3669
3670 /**
3671 * Helper class for array constructor lookup; an array constructor lookup
3672 * is simulated by looking up a method that returns the array type specified
3673 * as qualifier, and that accepts a single int parameter (size of the array).
3674 */
3675 class ArrayConstructorReferenceLookupHelper extends ReferenceLookupHelper {
3676
3677 ArrayConstructorReferenceLookupHelper(JCMemberReference referenceTree, Type site, List<Type> argtypes,
3678 List<Type> typeargtypes, MethodResolutionPhase maxPhase) {
3679 super(referenceTree, names.init, site, argtypes, typeargtypes, maxPhase);
3680 }
3681
3682 @Override
3683 protected Symbol lookup(Env<AttrContext> env, MethodResolutionPhase phase) {
3684 WriteableScope sc = WriteableScope.create(syms.arrayClass);
3685 MethodSymbol arrayConstr = new MethodSymbol(PUBLIC, name, null, site.tsym);
3686 arrayConstr.type = new MethodType(List.of(syms.intType), site, List.nil(), syms.methodClass);
3687 sc.enter(arrayConstr);
3688 return findMethodInScope(env, site, name, argtypes, typeargtypes, sc, methodNotFound, phase.isBoxingRequired(), phase.isVarargsRequired(), false);
3689 }
3690
3691 @Override
3692 ReferenceKind referenceKind(Symbol sym) {
3693 return ReferenceKind.ARRAY_CTOR;
3694 }
3695 }
3696
3697 /**
3698 * Helper class for constructor reference lookup. The lookup logic is based
3699 * upon either Resolve.findMethod or Resolve.findDiamond - depending on
3700 * whether the constructor reference needs diamond inference (this is the case
3701 * if the qualifier type is raw). A special erroneous symbol is returned
3702 * if the lookup returns the constructor of an inner class and there's no
3703 * enclosing instance in scope.
3704 */
3705 class ConstructorReferenceLookupHelper extends ReferenceLookupHelper {
3706
3707 boolean needsInference;
3708
3709 ConstructorReferenceLookupHelper(JCMemberReference referenceTree, Type site, List<Type> argtypes,
3710 List<Type> typeargtypes, MethodResolutionPhase maxPhase) {
3711 super(referenceTree, names.init, site, argtypes, typeargtypes, maxPhase);
3712 if (site.isRaw()) {
3713 this.site = new ClassType(site.getEnclosingType(),
3714 !(site.tsym.isInner() && site.getEnclosingType().isRaw()) ?
3715 site.tsym.type.getTypeArguments() : List.nil(), site.tsym, site.getMetadata());
3716 needsInference = true;
3717 }
3718 }
3719
3720 @Override
3721 protected Symbol lookup(Env<AttrContext> env, MethodResolutionPhase phase) {
3722 Symbol sym = needsInference ?
3723 findDiamond(env, site, argtypes, typeargtypes, phase.isBoxingRequired(), phase.isVarargsRequired()) :
3724 findMethod(env, site, name, argtypes, typeargtypes,
3725 phase.isBoxingRequired(), phase.isVarargsRequired());
3726 return enclosingInstanceMissing(env, site) ? new BadConstructorReferenceError(sym) : sym;
3727 }
3728
3729 @Override
3730 ReferenceKind referenceKind(Symbol sym) {
3731 return site.getEnclosingType().hasTag(NONE) ?
3732 ReferenceKind.TOPLEVEL : ReferenceKind.IMPLICIT_INNER;
3733 }
3734 }
3735
3736 /**
3737 * Main overload resolution routine. On each overload resolution step, a
3738 * lookup helper class is used to perform the method/constructor lookup;
3739 * at the end of the lookup, the helper is used to validate the results
3740 * (this last step might trigger overload resolution diagnostics).
3741 */
3742 Symbol lookupMethod(Env<AttrContext> env, DiagnosticPosition pos, Symbol location, MethodCheck methodCheck, LookupHelper lookupHelper) {
3743 MethodResolutionContext resolveContext = new MethodResolutionContext();
3744 resolveContext.methodCheck = methodCheck;
3745 return lookupMethod(env, pos, location, resolveContext, lookupHelper);
3746 }
3747
3748 Symbol lookupMethod(Env<AttrContext> env, DiagnosticPosition pos, Symbol location,
3749 MethodResolutionContext resolveContext, LookupHelper lookupHelper) {
3750 MethodResolutionContext prevResolutionContext = currentResolutionContext;
3751 try {
3752 Symbol bestSoFar = methodNotFound;
3753 currentResolutionContext = resolveContext;
3754 for (MethodResolutionPhase phase : methodResolutionSteps) {
3755 if (lookupHelper.shouldStop(bestSoFar, phase))
3756 break;
3757 MethodResolutionPhase prevPhase = currentResolutionContext.step;
3758 Symbol prevBest = bestSoFar;
3759 currentResolutionContext.step = phase;
3760 Symbol sym = lookupHelper.lookup(env, phase);
3761 lookupHelper.debug(pos, sym);
3762 bestSoFar = phase.mergeResults(bestSoFar, sym);
3763 env.info.pendingResolutionPhase = (prevBest == bestSoFar) ? prevPhase : phase;
3764 }
3765 return lookupHelper.access(env, pos, location, bestSoFar);
3766 } finally {
3767 currentResolutionContext = prevResolutionContext;
3768 }
3769 }
3770
3771 /**
3772 * Resolve `c.name' where name == this or name == super.
3773 * @param pos The position to use for error reporting.
3774 * @param env The environment current at the expression.
3775 * @param c The qualifier.
3776 * @param name The identifier's name.
3777 */
3778 Symbol resolveSelf(DiagnosticPosition pos,
3779 Env<AttrContext> env,
3780 TypeSymbol c,
3781 Name name) {
3782 Assert.check(name == names._this || name == names._super);
3783 Env<AttrContext> env1 = env;
3784 boolean staticOnly = false;
3785 while (env1.outer != null) {
3786 if (isStatic(env1)) staticOnly = true;
3787 if (env1.enclClass.sym == c) {
3788 Symbol sym = env1.info.scope.findFirst(name);
3789 if (sym != null) {
3790 if (staticOnly)
3791 sym = new StaticError(sym);
3792 else if (env1.info.ctorPrologue && !isAllowedEarlyReference(pos, env1, (VarSymbol)sym))
3793 sym = new RefBeforeCtorCalledError(sym);
3794 return accessBase(sym, pos, env.enclClass.sym.type,
3795 name, true);
3796 }
3797 }
3798 if ((env1.enclClass.sym.flags() & STATIC) != 0) staticOnly = true;
3799 env1 = env1.outer;
3800 }
3801 if (c.isInterface() &&
3802 name == names._super && !isStatic(env) &&
3803 types.isDirectSuperInterface(c, env.enclClass.sym)) {
3804 //this might be a default super call if one of the superinterfaces is 'c'
3805 for (Type t : pruneInterfaces(env.enclClass.type)) {
3806 if (t.tsym == c) {
3807 if (env.info.ctorPrologue)
3808 log.error(pos, Errors.CantRefBeforeCtorCalled(name));
3809 env.info.defaultSuperCallSite = t;
3810 return new VarSymbol(0, names._super,
3811 types.asSuper(env.enclClass.type, c), env.enclClass.sym);
3812 }
3813 }
3814 //find a direct supertype that is a subtype of 'c'
3815 for (Type i : types.directSupertypes(env.enclClass.type)) {
3816 if (i.tsym.isSubClass(c, types) && i.tsym != c) {
3817 log.error(pos,
3818 Errors.IllegalDefaultSuperCall(c,
3819 Fragments.RedundantSupertype(c, i)));
3820 return syms.errSymbol;
3821 }
3822 }
3823 Assert.error();
3824 }
3825 log.error(pos, Errors.NotEnclClass(c));
3826 return syms.errSymbol;
3827 }
3828 //where
3829 private List<Type> pruneInterfaces(Type t) {
3830 ListBuffer<Type> result = new ListBuffer<>();
3831 for (Type t1 : types.interfaces(t)) {
3832 boolean shouldAdd = true;
3833 for (Type t2 : types.directSupertypes(t)) {
3834 if (t1 != t2 && !t2.hasTag(ERROR) && types.isSubtypeNoCapture(t2, t1)) {
3835 shouldAdd = false;
3836 }
3837 }
3838 if (shouldAdd) {
3839 result.append(t1);
3840 }
3841 }
3842 return result.toList();
3843 }
3844
3845 /**
3846 * Determine if an early instance field reference may appear in a constructor prologue.
3847 *
3848 * <p>
3849 * This is only allowed when:
3850 * - The field is being assigned a value (i.e., written but not read)
3851 * - The field is not inherited from a superclass
3852 * - The assignment is not within a lambda, because that would require
3853 * capturing 'this' which is not allowed prior to super().
3854 *
3855 * <p>
3856 * Note, this method doesn't catch all such scenarios, because this method
3857 * is invoked for symbol "x" only for "x = 42" but not for "this.x = 42".
3858 * We also don't verify that the field has no initializer, which is required.
3859 * To catch those cases, we rely on similar logic in Attr.checkAssignable().
3860 */
3861 private boolean isAllowedEarlyReference(DiagnosticPosition pos, Env<AttrContext> env, VarSymbol v) {
3862
3863 // Check assumptions
3864 Assert.check(env.info.ctorPrologue);
3865 Assert.check((v.flags_field & STATIC) == 0);
3866
3867 // The symbol must appear in the LHS of an assignment statement
3868 if (!(env.tree instanceof JCAssign assign))
3869 return false;
3870
3871 // The assignment statement must not be within a lambda
3872 if (env.info.isLambda)
3873 return false;
3874
3875 // Get the symbol's qualifier, if any
3876 JCExpression lhs = TreeInfo.skipParens(assign.lhs);
3877 JCExpression base;
3878 switch (lhs.getTag()) {
3879 case IDENT:
3880 base = null;
3881 break;
3882 case SELECT:
3883 JCFieldAccess select = (JCFieldAccess)lhs;
3884 base = select.selected;
3885 if (!TreeInfo.isExplicitThisReference(types, (ClassType)env.enclClass.type, base))
3886 return false;
3887 break;
3888 default:
3889 return false;
3890 }
3891
3892 // If an early reference, the field must not be declared in a superclass
3893 if (isEarlyReference(env, base, v) && v.owner != env.enclClass.sym)
3894 return false;
3895
3896 // The flexible constructors feature must be enabled
3897 preview.checkSourceLevel(pos, Feature.FLEXIBLE_CONSTRUCTORS);
3898
3899 // OK
3900 return true;
3901 }
3902
3903 /**
3904 * Determine if the variable appearance constitutes an early reference to the current class.
3905 *
3906 * <p>
3907 * This means the variable is an instance field of the current class and it appears
3908 * in an early initialization context of it (i.e., one of its constructor prologues).
3909 *
3910 * <p>
3911 * Such a reference is only allowed for assignments to non-initialized fields that are
3912 * not inherited from a superclass, though that is not enforced by this method.
3913 *
3914 * @param env The current environment
3915 * @param base Variable qualifier, if any, otherwise null
3916 * @param v The variable
3917 */
3918 public boolean isEarlyReference(Env<AttrContext> env, JCTree base, VarSymbol v) {
3919 return env.info.ctorPrologue &&
3920 (v.flags() & STATIC) == 0 &&
3921 v.owner.kind == TYP &&
3922 types.isSubtype(env.enclClass.type, v.owner.type) &&
3923 (base == null || TreeInfo.isExplicitThisReference(types, (ClassType)env.enclClass.type, base));
3924 }
3925
3926 /**
3927 * Resolve `c.this' for an enclosing class c that contains the
3928 * named member.
3929 * @param pos The position to use for error reporting.
3930 * @param env The environment current at the expression.
3931 * @param member The member that must be contained in the result.
3932 */
3933 Symbol resolveSelfContaining(DiagnosticPosition pos,
3934 Env<AttrContext> env,
3935 Symbol member,
3936 boolean isSuperCall) {
3937 Symbol sym = resolveSelfContainingInternal(env, member, isSuperCall);
3938 if (sym == null) {
3939 log.error(pos, Errors.EnclClassRequired(member));
3940 return syms.errSymbol;
3941 } else {
3942 return accessBase(sym, pos, env.enclClass.sym.type, sym.name, true);
3943 }
3944 }
3945
3946 boolean enclosingInstanceMissing(Env<AttrContext> env, Type type) {
3947 if (type.hasTag(CLASS) && type.getEnclosingType().hasTag(CLASS)) {
3948 Symbol encl = resolveSelfContainingInternal(env, type.tsym, false);
3949 return encl == null || encl.kind.isResolutionError();
3950 }
3951 return false;
3952 }
3953
3954 private Symbol resolveSelfContainingInternal(Env<AttrContext> env,
3955 Symbol member,
3956 boolean isSuperCall) {
3957 Name name = names._this;
3958 Env<AttrContext> env1 = isSuperCall ? env.outer : env;
3959 boolean staticOnly = false;
3960 if (env1 != null) {
3961 while (env1 != null && env1.outer != null) {
3962 if (isStatic(env1)) staticOnly = true;
3963 if (env1.enclClass.sym.isSubClass(member.owner.enclClass(), types)) {
3964 Symbol sym = env1.info.scope.findFirst(name);
3965 if (sym != null) {
3966 if (staticOnly) sym = new StaticError(sym);
3967 return sym;
3968 }
3969 }
3970 if ((env1.enclClass.sym.flags() & STATIC) != 0)
3971 staticOnly = true;
3972 env1 = env1.outer;
3973 }
3974 }
3975 return null;
3976 }
3977
3978 /**
3979 * Resolve an appropriate implicit this instance for t's container.
3980 * JLS 8.8.5.1 and 15.9.2
3981 */
3982 Type resolveImplicitThis(DiagnosticPosition pos, Env<AttrContext> env, Type t) {
3983 return resolveImplicitThis(pos, env, t, false);
3984 }
3985
3986 Type resolveImplicitThis(DiagnosticPosition pos, Env<AttrContext> env, Type t, boolean isSuperCall) {
3987 Type thisType = (t.tsym.owner.kind.matches(KindSelector.VAL_MTH)
3988 ? resolveSelf(pos, env, t.getEnclosingType().tsym, names._this)
3989 : resolveSelfContaining(pos, env, t.tsym, isSuperCall)).type;
3990 if (env.info.ctorPrologue && thisType.tsym == env.enclClass.sym) {
3991 log.error(pos, Errors.CantRefBeforeCtorCalled(names._this));
3992 }
3993 return thisType;
3994 }
3995
3996 /* ***************************************************************************
3997 * ResolveError classes, indicating error situations when accessing symbols
3998 ****************************************************************************/
3999
4000 //used by TransTypes when checking target type of synthetic cast
4001 public void logAccessErrorInternal(Env<AttrContext> env, JCTree tree, Type type) {
4002 AccessError error = new AccessError(env, env.enclClass.type, type.tsym);
4003 logResolveError(error, tree.pos(), env.enclClass.sym, env.enclClass.type, null, null, null);
4004 }
4005 //where
4006 private void logResolveError(ResolveError error,
4007 DiagnosticPosition pos,
4008 Symbol location,
4009 Type site,
4010 Name name,
4011 List<Type> argtypes,
4012 List<Type> typeargtypes) {
4013 JCDiagnostic d = error.getDiagnostic(JCDiagnostic.DiagnosticType.ERROR,
4014 pos, location, site, name, argtypes, typeargtypes);
4015 if (d != null) {
4016 d.setFlag(DiagnosticFlag.RESOLVE_ERROR);
4017 log.report(d);
4018 }
4019 }
4020
4021 private final LocalizedString noArgs = new LocalizedString("compiler.misc.no.args");
4022
4023 public Object methodArguments(List<Type> argtypes) {
4024 if (argtypes == null || argtypes.isEmpty()) {
4025 return noArgs;
4026 } else {
4027 ListBuffer<Object> diagArgs = new ListBuffer<>();
4028 for (Type t : argtypes) {
4029 if (t.hasTag(DEFERRED)) {
4030 diagArgs.append(((DeferredAttr.DeferredType)t).tree);
4031 } else {
4032 diagArgs.append(t);
4033 }
4034 }
4035 return diagArgs;
4036 }
4037 }
4038
4039 /** check if a type is a subtype of Serializable, if that is available.*/
4040 boolean isSerializable(Type t) {
4041 try {
4042 syms.serializableType.complete();
4043 }
4044 catch (CompletionFailure e) {
4045 return false;
4046 }
4047 return types.isSubtype(t, syms.serializableType);
4048 }
4049
4050 /**
4051 * Root class for resolution errors. Subclass of ResolveError
4052 * represent a different kinds of resolution error - as such they must
4053 * specify how they map into concrete compiler diagnostics.
4054 */
4055 abstract class ResolveError extends Symbol {
4056
4057 /** The name of the kind of error, for debugging only. */
4058 final String debugName;
4059
4060 ResolveError(Kind kind, String debugName) {
4061 super(kind, 0, null, null, null);
4062 this.debugName = debugName;
4063 }
4064
4065 @Override @DefinedBy(Api.LANGUAGE_MODEL)
4066 public <R, P> R accept(ElementVisitor<R, P> v, P p) {
4067 throw new AssertionError();
4068 }
4069
4070 @Override
4071 public String toString() {
4072 return debugName;
4073 }
4074
4075 @Override
4076 public boolean exists() {
4077 return false;
4078 }
4079
4080 @Override
4081 public boolean isStatic() {
4082 return false;
4083 }
4084
4085 /**
4086 * Create an external representation for this erroneous symbol to be
4087 * used during attribution - by default this returns the symbol of a
4088 * brand new error type which stores the original type found
4089 * during resolution.
4090 *
4091 * @param name the name used during resolution
4092 * @param location the location from which the symbol is accessed
4093 */
4094 protected Symbol access(Name name, TypeSymbol location) {
4095 return types.createErrorType(name, location, syms.errSymbol.type).tsym;
4096 }
4097
4098 /**
4099 * Create a diagnostic representing this resolution error.
4100 *
4101 * @param dkind The kind of the diagnostic to be created (e.g error).
4102 * @param pos The position to be used for error reporting.
4103 * @param site The original type from where the selection took place.
4104 * @param name The name of the symbol to be resolved.
4105 * @param argtypes The invocation's value arguments,
4106 * if we looked for a method.
4107 * @param typeargtypes The invocation's type arguments,
4108 * if we looked for a method.
4109 */
4110 abstract JCDiagnostic getDiagnostic(JCDiagnostic.DiagnosticType dkind,
4111 DiagnosticPosition pos,
4112 Symbol location,
4113 Type site,
4114 Name name,
4115 List<Type> argtypes,
4116 List<Type> typeargtypes);
4117 }
4118
4119 /**
4120 * This class is the root class of all resolution errors caused by
4121 * an invalid symbol being found during resolution.
4122 */
4123 abstract class InvalidSymbolError extends ResolveError {
4124
4125 /** The invalid symbol found during resolution */
4126 Symbol sym;
4127
4128 InvalidSymbolError(Kind kind, Symbol sym, String debugName) {
4129 super(kind, debugName);
4130 this.sym = sym;
4131 }
4132
4133 @Override
4134 public boolean exists() {
4135 return true;
4136 }
4137
4138 @Override
4139 public String toString() {
4140 return super.toString() + " wrongSym=" + sym;
4141 }
4142
4143 @Override
4144 public Symbol access(Name name, TypeSymbol location) {
4145 if (!sym.kind.isResolutionError() && sym.kind.matches(KindSelector.TYP))
4146 return types.createErrorType(name, location, sym.type).tsym;
4147 else
4148 return sym;
4149 }
4150 }
4151
4152 class BadRestrictedTypeError extends ResolveError {
4153 private final Name typeName;
4154 BadRestrictedTypeError(Name typeName) {
4155 super(Kind.BAD_RESTRICTED_TYPE, "bad var use");
4156 this.typeName = typeName;
4157 }
4158
4159 @Override
4160 JCDiagnostic getDiagnostic(DiagnosticType dkind, DiagnosticPosition pos, Symbol location, Type site, Name name, List<Type> argtypes, List<Type> typeargtypes) {
4161 return diags.create(dkind, log.currentSource(), pos, "illegal.ref.to.restricted.type", typeName);
4162 }
4163 }
4164
4165 /**
4166 * InvalidSymbolError error class indicating that a symbol matching a
4167 * given name does not exists in a given site.
4168 */
4169 class SymbolNotFoundError extends ResolveError {
4170
4171 SymbolNotFoundError(Kind kind) {
4172 this(kind, "symbol not found error");
4173 }
4174
4175 SymbolNotFoundError(Kind kind, String debugName) {
4176 super(kind, debugName);
4177 }
4178
4179 @Override
4180 JCDiagnostic getDiagnostic(JCDiagnostic.DiagnosticType dkind,
4181 DiagnosticPosition pos,
4182 Symbol location,
4183 Type site,
4184 Name name,
4185 List<Type> argtypes,
4186 List<Type> typeargtypes) {
4187 argtypes = argtypes == null ? List.nil() : argtypes;
4188 typeargtypes = typeargtypes == null ? List.nil() : typeargtypes;
4189 if (name == names.error)
4190 return null;
4191
4192 boolean hasLocation = false;
4193 if (location == null) {
4194 location = site.tsym;
4195 }
4196 if (!location.name.isEmpty()) {
4197 if (location.kind == PCK && !site.tsym.exists() && location.name != names.java) {
4198 return diags.create(dkind, log.currentSource(), pos,
4199 "doesnt.exist", location);
4200 }
4201 hasLocation = !location.name.equals(names._this) &&
4202 !location.name.equals(names._super);
4203 }
4204 boolean isConstructor = name == names.init;
4205 KindName kindname = isConstructor ? KindName.CONSTRUCTOR : kind.absentKind();
4206 Name idname = isConstructor ? site.tsym.name : name;
4207 String errKey = getErrorKey(kindname, typeargtypes.nonEmpty(), hasLocation);
4208 if (hasLocation) {
4209 return diags.create(dkind, log.currentSource(), pos,
4210 errKey, kindname, idname, //symbol kindname, name
4211 typeargtypes, args(argtypes), //type parameters and arguments (if any)
4212 getLocationDiag(location, site)); //location kindname, type
4213 }
4214 else {
4215 return diags.create(dkind, log.currentSource(), pos,
4216 errKey, kindname, idname, //symbol kindname, name
4217 typeargtypes, args(argtypes)); //type parameters and arguments (if any)
4218 }
4219 }
4220 //where
4221 private Object args(List<Type> args) {
4222 return args.isEmpty() ? args : methodArguments(args);
4223 }
4224
4225 private String getErrorKey(KindName kindname, boolean hasTypeArgs, boolean hasLocation) {
4226 String key = "cant.resolve";
4227 String suffix = hasLocation ? ".location" : "";
4228 switch (kindname) {
4229 case METHOD:
4230 case CONSTRUCTOR: {
4231 suffix += ".args";
4232 suffix += hasTypeArgs ? ".params" : "";
4233 }
4234 }
4235 return key + suffix;
4236 }
4237 private JCDiagnostic getLocationDiag(Symbol location, Type site) {
4238 if (location.kind == VAR) {
4239 return diags.fragment(Fragments.Location1(kindName(location),
4240 location,
4241 location.type));
4242 } else {
4243 return diags.fragment(Fragments.Location(typeKindName(site),
4244 site,
4245 null));
4246 }
4247 }
4248 }
4249
4250 /**
4251 * InvalidSymbolError error class indicating that a given symbol
4252 * (either a method, a constructor or an operand) is not applicable
4253 * given an actual arguments/type argument list.
4254 */
4255 class InapplicableSymbolError extends ResolveError {
4256
4257 protected MethodResolutionContext resolveContext;
4258
4259 InapplicableSymbolError(MethodResolutionContext context) {
4260 this(WRONG_MTH, "inapplicable symbol error", context);
4261 }
4262
4263 protected InapplicableSymbolError(Kind kind, String debugName, MethodResolutionContext context) {
4264 super(kind, debugName);
4265 this.resolveContext = context;
4266 }
4267
4268 @Override
4269 public String toString() {
4270 return super.toString();
4271 }
4272
4273 @Override
4274 public boolean exists() {
4275 return true;
4276 }
4277
4278 @Override
4279 JCDiagnostic getDiagnostic(JCDiagnostic.DiagnosticType dkind,
4280 DiagnosticPosition pos,
4281 Symbol location,
4282 Type site,
4283 Name name,
4284 List<Type> argtypes,
4285 List<Type> typeargtypes) {
4286 if (name == names.error)
4287 return null;
4288
4289 Pair<Symbol, JCDiagnostic> c = errCandidate();
4290 Symbol ws = c.fst.asMemberOf(site, types);
4291 UnaryOperator<JCDiagnostic> rewriter = compactMethodDiags ?
4292 d -> MethodResolutionDiagHelper.rewrite(diags, pos, log.currentSource(), dkind, c.snd) : null;
4293
4294 // If the problem is due to type arguments, then the method parameters aren't relevant,
4295 // so use the error message that omits them to avoid confusion.
4296 switch (c.snd.getCode()) {
4297 case "compiler.misc.wrong.number.type.args":
4298 case "compiler.misc.explicit.param.do.not.conform.to.bounds":
4299 return diags.create(dkind, log.currentSource(), pos,
4300 "cant.apply.symbol.noargs",
4301 rewriter,
4302 kindName(ws),
4303 ws.name == names.init ? ws.owner.name : ws.name,
4304 kindName(ws.owner),
4305 ws.owner.type,
4306 c.snd);
4307 default:
4308 // Avoid saying "constructor Array in class Array"
4309 if (ws.owner == syms.arrayClass && ws.name == names.init) {
4310 return diags.create(dkind, log.currentSource(), pos,
4311 "cant.apply.array.ctor",
4312 rewriter,
4313 methodArguments(ws.type.getParameterTypes()),
4314 methodArguments(argtypes),
4315 c.snd);
4316 }
4317 return diags.create(dkind, log.currentSource(), pos,
4318 "cant.apply.symbol",
4319 rewriter,
4320 kindName(ws),
4321 ws.name == names.init ? ws.owner.name : ws.name,
4322 methodArguments(ws.type.getParameterTypes()),
4323 methodArguments(argtypes),
4324 kindName(ws.owner),
4325 ws.owner.type,
4326 c.snd);
4327 }
4328 }
4329
4330 @Override
4331 public Symbol access(Name name, TypeSymbol location) {
4332 Pair<Symbol, JCDiagnostic> cand = errCandidate();
4333 TypeSymbol errSymbol = types.createErrorType(name, location, cand != null ? cand.fst.type : syms.errSymbol.type).tsym;
4334 if (cand != null) {
4335 attrRecover.wrongMethodSymbolCandidate(errSymbol, cand.fst, cand.snd);
4336 }
4337 return errSymbol;
4338 }
4339
4340 protected Pair<Symbol, JCDiagnostic> errCandidate() {
4341 Candidate bestSoFar = null;
4342 for (Candidate c : resolveContext.candidates) {
4343 if (c.isApplicable()) continue;
4344 bestSoFar = c;
4345 }
4346 Assert.checkNonNull(bestSoFar);
4347 return new Pair<>(bestSoFar.sym, bestSoFar.details);
4348 }
4349 }
4350
4351 /**
4352 * ResolveError error class indicating that a symbol (either methods, constructors or operand)
4353 * is not applicable given an actual arguments/type argument list.
4354 */
4355 class InapplicableSymbolsError extends InapplicableSymbolError {
4356
4357 InapplicableSymbolsError(MethodResolutionContext context) {
4358 super(WRONG_MTHS, "inapplicable symbols", context);
4359 }
4360
4361 @Override
4362 JCDiagnostic getDiagnostic(JCDiagnostic.DiagnosticType dkind,
4363 DiagnosticPosition pos,
4364 Symbol location,
4365 Type site,
4366 Name name,
4367 List<Type> argtypes,
4368 List<Type> typeargtypes) {
4369 Map<Symbol, JCDiagnostic> candidatesMap = mapCandidates();
4370 Map<Symbol, JCDiagnostic> filteredCandidates = compactMethodDiags ?
4371 filterCandidates(candidatesMap) :
4372 mapCandidates();
4373 if (filteredCandidates.isEmpty()) {
4374 filteredCandidates = candidatesMap;
4375 }
4376 boolean truncatedDiag = candidatesMap.size() != filteredCandidates.size();
4377 if (filteredCandidates.size() > 1) {
4378 JCDiagnostic err = diags.create(dkind,
4379 null,
4380 truncatedDiag ?
4381 EnumSet.of(DiagnosticFlag.COMPRESSED) :
4382 EnumSet.noneOf(DiagnosticFlag.class),
4383 log.currentSource(),
4384 pos,
4385 "cant.apply.symbols",
4386 name == names.init ? KindName.CONSTRUCTOR : kind.absentKind(),
4387 name == names.init ? site.tsym.name : name,
4388 methodArguments(argtypes));
4389 return new JCDiagnostic.MultilineDiagnostic(err, candidateDetails(filteredCandidates, site));
4390 } else if (filteredCandidates.size() == 1) {
4391 Map.Entry<Symbol, JCDiagnostic> _e =
4392 filteredCandidates.entrySet().iterator().next();
4393 final Pair<Symbol, JCDiagnostic> p = new Pair<>(_e.getKey(), _e.getValue());
4394 JCDiagnostic d = new InapplicableSymbolError(resolveContext) {
4395 @Override
4396 protected Pair<Symbol, JCDiagnostic> errCandidate() {
4397 return p;
4398 }
4399 }.getDiagnostic(dkind, pos,
4400 location, site, name, argtypes, typeargtypes);
4401 if (truncatedDiag) {
4402 d.setFlag(DiagnosticFlag.COMPRESSED);
4403 }
4404 return d;
4405 } else {
4406 return new SymbolNotFoundError(ABSENT_MTH).getDiagnostic(dkind, pos,
4407 location, site, name, argtypes, typeargtypes);
4408 }
4409 }
4410 //where
4411 private Map<Symbol, JCDiagnostic> mapCandidates() {
4412 MostSpecificMap candidates = new MostSpecificMap();
4413 for (Candidate c : resolveContext.candidates) {
4414 if (c.isApplicable()) continue;
4415 candidates.put(c);
4416 }
4417 return candidates;
4418 }
4419
4420 @SuppressWarnings("serial")
4421 private class MostSpecificMap extends LinkedHashMap<Symbol, JCDiagnostic> {
4422 private void put(Candidate c) {
4423 ListBuffer<Symbol> overridden = new ListBuffer<>();
4424 for (Symbol s : keySet()) {
4425 if (s == c.sym) {
4426 continue;
4427 }
4428 if (c.sym.overrides(s, (TypeSymbol)s.owner, types, false)) {
4429 overridden.add(s);
4430 } else if (s.overrides(c.sym, (TypeSymbol)c.sym.owner, types, false)) {
4431 return;
4432 }
4433 }
4434 for (Symbol s : overridden) {
4435 remove(s);
4436 }
4437 put(c.sym, c.details);
4438 }
4439 }
4440
4441 Map<Symbol, JCDiagnostic> filterCandidates(Map<Symbol, JCDiagnostic> candidatesMap) {
4442 Map<Symbol, JCDiagnostic> candidates = new LinkedHashMap<>();
4443 for (Map.Entry<Symbol, JCDiagnostic> _entry : candidatesMap.entrySet()) {
4444 JCDiagnostic d = _entry.getValue();
4445 if (!new Template(MethodCheckDiag.ARITY_MISMATCH.regex()).matches(d)) {
4446 candidates.put(_entry.getKey(), d);
4447 }
4448 }
4449 return candidates;
4450 }
4451
4452 private List<JCDiagnostic> candidateDetails(Map<Symbol, JCDiagnostic> candidatesMap, Type site) {
4453 List<JCDiagnostic> details = List.nil();
4454 for (Map.Entry<Symbol, JCDiagnostic> _entry : candidatesMap.entrySet()) {
4455 Symbol sym = _entry.getKey();
4456 JCDiagnostic detailDiag =
4457 diags.fragment(Fragments.InapplicableMethod(Kinds.kindName(sym),
4458 sym.location(site, types),
4459 sym.asMemberOf(site, types),
4460 _entry.getValue()));
4461 details = details.prepend(detailDiag);
4462 }
4463 //typically members are visited in reverse order (see Scope)
4464 //so we need to reverse the candidate list so that candidates
4465 //conform to source order
4466 return details;
4467 }
4468
4469 @Override
4470 protected Pair<Symbol, JCDiagnostic> errCandidate() {
4471 Map<Symbol, JCDiagnostic> candidatesMap = mapCandidates();
4472 Map<Symbol, JCDiagnostic> filteredCandidates = filterCandidates(candidatesMap);
4473 if (filteredCandidates.size() == 1) {
4474 return Pair.of(filteredCandidates.keySet().iterator().next(),
4475 filteredCandidates.values().iterator().next());
4476 }
4477 return null;
4478 }
4479 }
4480
4481 /**
4482 * DiamondError error class indicating that a constructor symbol is not applicable
4483 * given an actual arguments/type argument list using diamond inference.
4484 */
4485 class DiamondError extends InapplicableSymbolError {
4486
4487 Symbol sym;
4488
4489 public DiamondError(Symbol sym, MethodResolutionContext context) {
4490 super(sym.kind, "diamondError", context);
4491 this.sym = sym;
4492 }
4493
4494 JCDiagnostic getDetails() {
4495 return (sym.kind == WRONG_MTH) ?
4496 ((InapplicableSymbolError)sym.baseSymbol()).errCandidate().snd :
4497 null;
4498 }
4499
4500 @Override
4501 JCDiagnostic getDiagnostic(DiagnosticType dkind, DiagnosticPosition pos,
4502 Symbol location, Type site, Name name, List<Type> argtypes, List<Type> typeargtypes) {
4503 JCDiagnostic details = getDetails();
4504 if (details != null && compactMethodDiags) {
4505 JCDiagnostic simpleDiag =
4506 MethodResolutionDiagHelper.rewrite(diags, pos, log.currentSource(), dkind, details);
4507 if (simpleDiag != null) {
4508 return simpleDiag;
4509 }
4510 }
4511 String key = details == null ?
4512 "cant.apply.diamond" :
4513 "cant.apply.diamond.1";
4514 return diags.create(dkind, log.currentSource(), pos, key,
4515 Fragments.Diamond(site.tsym), details);
4516 }
4517 }
4518
4519 /**
4520 * An InvalidSymbolError error class indicating that a symbol is not
4521 * accessible from a given site
4522 */
4523 class AccessError extends InvalidSymbolError {
4524
4525 private Env<AttrContext> env;
4526 private Type site;
4527
4528 AccessError(Env<AttrContext> env, Type site, Symbol sym) {
4529 super(HIDDEN, sym, "access error");
4530 this.env = env;
4531 this.site = site;
4532 }
4533
4534 @Override
4535 public boolean exists() {
4536 return false;
4537 }
4538
4539 @Override
4540 JCDiagnostic getDiagnostic(JCDiagnostic.DiagnosticType dkind,
4541 DiagnosticPosition pos,
4542 Symbol location,
4543 Type site,
4544 Name name,
4545 List<Type> argtypes,
4546 List<Type> typeargtypes) {
4547 if (sym.name == names.init && sym.owner != site.tsym) {
4548 return new SymbolNotFoundError(ABSENT_MTH).getDiagnostic(dkind,
4549 pos, location, site, name, argtypes, typeargtypes);
4550 }
4551 else if ((sym.flags() & PUBLIC) != 0
4552 || (env != null && this.site != null
4553 && !isAccessible(env, this.site))) {
4554 if (sym.owner.kind == PCK) {
4555 return diags.create(dkind, log.currentSource(),
4556 pos, "not.def.access.package.cant.access",
4557 sym, sym.location(), inaccessiblePackageReason(env, sym.packge()));
4558 } else if ( sym.packge() != syms.rootPackage
4559 && !symbolPackageVisible(env, sym)) {
4560 return diags.create(dkind, log.currentSource(),
4561 pos, "not.def.access.class.intf.cant.access.reason",
4562 sym, sym.location(), sym.location().packge(),
4563 inaccessiblePackageReason(env, sym.packge()));
4564 } else {
4565 return diags.create(dkind, log.currentSource(),
4566 pos, "not.def.access.class.intf.cant.access",
4567 sym, sym.location());
4568 }
4569 }
4570 else if ((sym.flags() & (PRIVATE | PROTECTED)) != 0) {
4571 return diags.create(dkind, log.currentSource(),
4572 pos, "report.access", sym,
4573 asFlagSet(sym.flags() & (PRIVATE | PROTECTED)),
4574 sym.location());
4575 }
4576 else {
4577 return diags.create(dkind, log.currentSource(),
4578 pos, "not.def.public.cant.access", sym, sym.location());
4579 }
4580 }
4581
4582 private String toString(Type type) {
4583 StringBuilder sb = new StringBuilder();
4584 sb.append(type);
4585 if (type != null) {
4586 sb.append("[tsym:").append(type.tsym);
4587 if (type.tsym != null)
4588 sb.append("packge:").append(type.tsym.packge());
4589 sb.append("]");
4590 }
4591 return sb.toString();
4592 }
4593 }
4594
4595 class InvisibleSymbolError extends InvalidSymbolError {
4596
4597 private final Env<AttrContext> env;
4598 private final boolean suppressError;
4599
4600 InvisibleSymbolError(Env<AttrContext> env, boolean suppressError, Symbol sym) {
4601 super(HIDDEN, sym, "invisible class error");
4602 this.env = env;
4603 this.suppressError = suppressError;
4604 this.name = sym.name;
4605 }
4606
4607 @Override
4608 JCDiagnostic getDiagnostic(JCDiagnostic.DiagnosticType dkind,
4609 DiagnosticPosition pos,
4610 Symbol location,
4611 Type site,
4612 Name name,
4613 List<Type> argtypes,
4614 List<Type> typeargtypes) {
4615 if (suppressError)
4616 return null;
4617
4618 if (sym.kind == PCK) {
4619 JCDiagnostic details = inaccessiblePackageReason(env, sym.packge());
4620 return diags.create(dkind, log.currentSource(),
4621 pos, "package.not.visible", sym, details);
4622 }
4623
4624 JCDiagnostic details = inaccessiblePackageReason(env, sym.packge());
4625
4626 if (pos.getTree() != null) {
4627 Symbol o = sym;
4628 JCTree tree = pos.getTree();
4629
4630 while (o.kind != PCK && tree.hasTag(SELECT)) {
4631 o = o.owner;
4632 tree = ((JCFieldAccess) tree).selected;
4633 }
4634
4635 if (o.kind == PCK) {
4636 pos = tree.pos();
4637
4638 return diags.create(dkind, log.currentSource(),
4639 pos, "package.not.visible", o, details);
4640 }
4641 }
4642
4643 return diags.create(dkind, log.currentSource(),
4644 pos, "not.def.access.package.cant.access", sym, sym.packge(), details);
4645 }
4646 }
4647
4648 JCDiagnostic inaccessiblePackageReason(Env<AttrContext> env, PackageSymbol sym) {
4649 //no dependency:
4650 if (!env.toplevel.modle.readModules.contains(sym.modle)) {
4651 //does not read:
4652 if (sym.modle != syms.unnamedModule) {
4653 if (env.toplevel.modle != syms.unnamedModule) {
4654 return diags.fragment(Fragments.NotDefAccessDoesNotRead(env.toplevel.modle,
4655 sym,
4656 sym.modle));
4657 } else {
4658 return diags.fragment(Fragments.NotDefAccessDoesNotReadFromUnnamed(sym,
4659 sym.modle));
4660 }
4661 } else {
4662 return diags.fragment(Fragments.NotDefAccessDoesNotReadUnnamed(sym,
4663 env.toplevel.modle));
4664 }
4665 } else {
4666 if (sym.packge().modle.exports.stream().anyMatch(e -> e.packge == sym)) {
4667 //not exported to this module:
4668 if (env.toplevel.modle != syms.unnamedModule) {
4669 return diags.fragment(Fragments.NotDefAccessNotExportedToModule(sym,
4670 sym.modle,
4671 env.toplevel.modle));
4672 } else {
4673 return diags.fragment(Fragments.NotDefAccessNotExportedToModuleFromUnnamed(sym,
4674 sym.modle));
4675 }
4676 } else {
4677 //not exported:
4678 if (env.toplevel.modle != syms.unnamedModule) {
4679 return diags.fragment(Fragments.NotDefAccessNotExported(sym,
4680 sym.modle));
4681 } else {
4682 return diags.fragment(Fragments.NotDefAccessNotExportedFromUnnamed(sym,
4683 sym.modle));
4684 }
4685 }
4686 }
4687 }
4688
4689 /**
4690 * InvalidSymbolError error class indicating that an instance member
4691 * has erroneously been accessed from a static context.
4692 */
4693 class StaticError extends InvalidSymbolError {
4694
4695 StaticError(Symbol sym) {
4696 this(sym, "static error");
4697 }
4698
4699 StaticError(Symbol sym, String debugName) {
4700 super(STATICERR, sym, debugName);
4701 }
4702
4703 @Override
4704 JCDiagnostic getDiagnostic(JCDiagnostic.DiagnosticType dkind,
4705 DiagnosticPosition pos,
4706 Symbol location,
4707 Type site,
4708 Name name,
4709 List<Type> argtypes,
4710 List<Type> typeargtypes) {
4711 Symbol errSym = ((sym.kind == TYP && sym.type.hasTag(CLASS))
4712 ? types.erasure(sym.type).tsym
4713 : sym);
4714 return diags.create(dkind, log.currentSource(), pos,
4715 "non-static.cant.be.ref", kindName(sym), errSym);
4716 }
4717 }
4718
4719 /**
4720 * Specialization of {@link InvalidSymbolError} for illegal
4721 * early accesses within a constructor prologue.
4722 */
4723 class RefBeforeCtorCalledError extends StaticError {
4724
4725 RefBeforeCtorCalledError(Symbol sym) {
4726 super(sym, "prologue error");
4727 }
4728
4729 @Override
4730 JCDiagnostic getDiagnostic(JCDiagnostic.DiagnosticType dkind,
4731 DiagnosticPosition pos,
4732 Symbol location,
4733 Type site,
4734 Name name,
4735 List<Type> argtypes,
4736 List<Type> typeargtypes) {
4737 Symbol errSym = ((sym.kind == TYP && sym.type.hasTag(CLASS))
4738 ? types.erasure(sym.type).tsym
4739 : sym);
4740 return diags.create(dkind, log.currentSource(), pos,
4741 "cant.ref.before.ctor.called", errSym);
4742 }
4743 }
4744
4745 /**
4746 * InvalidSymbolError error class indicating that a pair of symbols
4747 * (either methods, constructors or operands) are ambiguous
4748 * given an actual arguments/type argument list.
4749 */
4750 class AmbiguityError extends ResolveError {
4751
4752 /** The other maximally specific symbol */
4753 List<Symbol> ambiguousSyms = List.nil();
4754
4755 @Override
4756 public boolean exists() {
4757 return true;
4758 }
4759
4760 AmbiguityError(Symbol sym1, Symbol sym2) {
4761 super(AMBIGUOUS, "ambiguity error");
4762 ambiguousSyms = flatten(sym2).appendList(flatten(sym1));
4763 }
4764
4765 private List<Symbol> flatten(Symbol sym) {
4766 if (sym.kind == AMBIGUOUS) {
4767 return ((AmbiguityError)sym.baseSymbol()).ambiguousSyms;
4768 } else {
4769 return List.of(sym);
4770 }
4771 }
4772
4773 AmbiguityError addAmbiguousSymbol(Symbol s) {
4774 ambiguousSyms = ambiguousSyms.prepend(s);
4775 return this;
4776 }
4777
4778 @Override
4779 JCDiagnostic getDiagnostic(JCDiagnostic.DiagnosticType dkind,
4780 DiagnosticPosition pos,
4781 Symbol location,
4782 Type site,
4783 Name name,
4784 List<Type> argtypes,
4785 List<Type> typeargtypes) {
4786 List<Symbol> diagSyms = ambiguousSyms.reverse();
4787 Symbol s1 = diagSyms.head;
4788 Symbol s2 = diagSyms.tail.head;
4789 Name sname = s1.name;
4790 if (sname == names.init) sname = s1.owner.name;
4791 return diags.create(dkind, log.currentSource(),
4792 pos, "ref.ambiguous", sname,
4793 kindName(s1),
4794 s1,
4795 s1.location(site, types),
4796 kindName(s2),
4797 s2,
4798 s2.location(site, types));
4799 }
4800
4801 /**
4802 * If multiple applicable methods are found during overload and none of them
4803 * is more specific than the others, attempt to merge their signatures.
4804 */
4805 Symbol mergeAbstracts(Type site) {
4806 List<Symbol> ambiguousInOrder = ambiguousSyms.reverse();
4807 return types.mergeAbstracts(ambiguousInOrder, site, true).orElse(this);
4808 }
4809
4810 @Override
4811 protected Symbol access(Name name, TypeSymbol location) {
4812 Symbol firstAmbiguity = ambiguousSyms.last();
4813 return firstAmbiguity.kind == TYP ?
4814 types.createErrorType(name, location, firstAmbiguity.type).tsym :
4815 firstAmbiguity;
4816 }
4817 }
4818
4819 class BadVarargsMethod extends ResolveError {
4820
4821 ResolveError delegatedError;
4822
4823 BadVarargsMethod(ResolveError delegatedError) {
4824 super(delegatedError.kind, "badVarargs");
4825 this.delegatedError = delegatedError;
4826 }
4827
4828 @Override
4829 public Symbol baseSymbol() {
4830 return delegatedError.baseSymbol();
4831 }
4832
4833 @Override
4834 protected Symbol access(Name name, TypeSymbol location) {
4835 return delegatedError.access(name, location);
4836 }
4837
4838 @Override
4839 public boolean exists() {
4840 return true;
4841 }
4842
4843 @Override
4844 JCDiagnostic getDiagnostic(DiagnosticType dkind, DiagnosticPosition pos, Symbol location, Type site, Name name, List<Type> argtypes, List<Type> typeargtypes) {
4845 return delegatedError.getDiagnostic(dkind, pos, location, site, name, argtypes, typeargtypes);
4846 }
4847 }
4848
4849 /**
4850 * BadMethodReferenceError error class indicating that a method reference symbol has been found,
4851 * but with the wrong staticness.
4852 */
4853 class BadMethodReferenceError extends StaticError {
4854
4855 boolean unboundLookup;
4856
4857 public BadMethodReferenceError(Symbol sym, boolean unboundLookup) {
4858 super(sym, "bad method ref error");
4859 this.unboundLookup = unboundLookup;
4860 }
4861
4862 @Override
4863 JCDiagnostic getDiagnostic(DiagnosticType dkind, DiagnosticPosition pos, Symbol location, Type site, Name name, List<Type> argtypes, List<Type> typeargtypes) {
4864 final String key;
4865 if (!unboundLookup) {
4866 key = "bad.static.method.in.bound.lookup";
4867 } else if (sym.isStatic()) {
4868 key = "bad.static.method.in.unbound.lookup";
4869 } else {
4870 key = "bad.instance.method.in.unbound.lookup";
4871 }
4872 return sym.kind.isResolutionError() ?
4873 ((ResolveError)sym).getDiagnostic(dkind, pos, location, site, name, argtypes, typeargtypes) :
4874 diags.create(dkind, log.currentSource(), pos, key, Kinds.kindName(sym), sym);
4875 }
4876 }
4877
4878 /**
4879 * BadConstructorReferenceError error class indicating that a constructor reference symbol has been found,
4880 * but pointing to a class for which an enclosing instance is not available.
4881 */
4882 class BadConstructorReferenceError extends InvalidSymbolError {
4883
4884 public BadConstructorReferenceError(Symbol sym) {
4885 super(MISSING_ENCL, sym, "BadConstructorReferenceError");
4886 }
4887
4888 @Override
4889 JCDiagnostic getDiagnostic(DiagnosticType dkind, DiagnosticPosition pos, Symbol location, Type site, Name name, List<Type> argtypes, List<Type> typeargtypes) {
4890 return diags.create(dkind, log.currentSource(), pos,
4891 "cant.access.inner.cls.constr", site.tsym.name, argtypes, site.getEnclosingType());
4892 }
4893 }
4894
4895 class BadClassFileError extends InvalidSymbolError {
4896
4897 private final CompletionFailure ex;
4898
4899 public BadClassFileError(CompletionFailure ex) {
4900 super(HIDDEN, ex.sym, "BadClassFileError");
4901 this.name = sym.name;
4902 this.ex = ex;
4903 }
4904
4905 @Override
4906 JCDiagnostic getDiagnostic(DiagnosticType dkind, DiagnosticPosition pos, Symbol location, Type site, Name name, List<Type> argtypes, List<Type> typeargtypes) {
4907 JCDiagnostic d = diags.create(dkind, log.currentSource(), pos,
4908 "cant.access", ex.sym, ex.getDetailValue());
4909
4910 d.setFlag(DiagnosticFlag.NON_DEFERRABLE);
4911 return d;
4912 }
4913
4914 }
4915
4916 /**
4917 * Helper class for method resolution diagnostic simplification.
4918 * Certain resolution diagnostic are rewritten as simpler diagnostic
4919 * where the enclosing resolution diagnostic (i.e. 'inapplicable method')
4920 * is stripped away, as it doesn't carry additional info. The logic
4921 * for matching a given diagnostic is given in terms of a template
4922 * hierarchy: a diagnostic template can be specified programmatically,
4923 * so that only certain diagnostics are matched. Each templete is then
4924 * associated with a rewriter object that carries out the task of rewtiting
4925 * the diagnostic to a simpler one.
4926 */
4927 static class MethodResolutionDiagHelper {
4928
4929 /**
4930 * A diagnostic rewriter transforms a method resolution diagnostic
4931 * into a simpler one
4932 */
4933 interface DiagnosticRewriter {
4934 JCDiagnostic rewriteDiagnostic(JCDiagnostic.Factory diags,
4935 DiagnosticPosition preferredPos, DiagnosticSource preferredSource,
4936 DiagnosticType preferredKind, JCDiagnostic d);
4937 }
4938
4939 /**
4940 * A diagnostic template is made up of two ingredients: (i) a regular
4941 * expression for matching a diagnostic key and (ii) a list of sub-templates
4942 * for matching diagnostic arguments.
4943 */
4944 static class Template {
4945
4946 /** regex used to match diag key */
4947 String regex;
4948
4949 /** templates used to match diagnostic args */
4950 Template[] subTemplates;
4951
4952 Template(String key, Template... subTemplates) {
4953 this.regex = key;
4954 this.subTemplates = subTemplates;
4955 }
4956
4957 /**
4958 * Returns true if the regex matches the diagnostic key and if
4959 * all diagnostic arguments are matches by corresponding sub-templates.
4960 */
4961 boolean matches(Object o) {
4962 JCDiagnostic d = (JCDiagnostic)o;
4963 Object[] args = d.getArgs();
4964 if (!d.getCode().matches(regex) ||
4965 subTemplates.length != d.getArgs().length) {
4966 return false;
4967 }
4968 for (int i = 0; i < args.length ; i++) {
4969 if (!subTemplates[i].matches(args[i])) {
4970 return false;
4971 }
4972 }
4973 return true;
4974 }
4975 }
4976
4977 /**
4978 * Common rewriter for all argument mismatch simplifications.
4979 */
4980 static class ArgMismatchRewriter implements DiagnosticRewriter {
4981
4982 /** the index of the subdiagnostic to be used as primary. */
4983 int causeIndex;
4984
4985 public ArgMismatchRewriter(int causeIndex) {
4986 this.causeIndex = causeIndex;
4987 }
4988
4989 @Override
4990 public JCDiagnostic rewriteDiagnostic(JCDiagnostic.Factory diags,
4991 DiagnosticPosition preferredPos, DiagnosticSource preferredSource,
4992 DiagnosticType preferredKind, JCDiagnostic d) {
4993 JCDiagnostic cause = (JCDiagnostic)d.getArgs()[causeIndex];
4994 DiagnosticPosition pos = d.getDiagnosticPosition();
4995 if (pos == null) {
4996 pos = preferredPos;
4997 }
4998 return diags.create(preferredKind, preferredSource, pos,
4999 "prob.found.req", cause);
5000 }
5001 }
5002
5003 /** a dummy template that match any diagnostic argument */
5004 static final Template skip = new Template("") {
5005 @Override
5006 boolean matches(Object d) {
5007 return true;
5008 }
5009 };
5010
5011 /** template for matching inference-free arguments mismatch failures */
5012 static final Template argMismatchTemplate = new Template(MethodCheckDiag.ARG_MISMATCH.regex(), skip);
5013
5014 /** template for matching inference related arguments mismatch failures */
5015 static final Template inferArgMismatchTemplate = new Template(MethodCheckDiag.ARG_MISMATCH.regex(), skip, skip) {
5016 @Override
5017 boolean matches(Object o) {
5018 if (!super.matches(o)) {
5019 return false;
5020 }
5021 JCDiagnostic d = (JCDiagnostic)o;
5022 @SuppressWarnings("unchecked")
5023 List<Type> tvars = (List<Type>)d.getArgs()[0];
5024 return !containsAny(d, tvars);
5025 }
5026
5027 BiPredicate<Object, List<Type>> containsPredicate = (o, ts) -> {
5028 if (o instanceof Type type) {
5029 return type.containsAny(ts);
5030 } else if (o instanceof JCDiagnostic diagnostic) {
5031 return containsAny(diagnostic, ts);
5032 } else {
5033 return false;
5034 }
5035 };
5036
5037 boolean containsAny(JCDiagnostic d, List<Type> ts) {
5038 return Stream.of(d.getArgs())
5039 .anyMatch(o -> containsPredicate.test(o, ts));
5040 }
5041 };
5042
5043 /** rewriter map used for method resolution simplification */
5044 static final Map<Template, DiagnosticRewriter> rewriters = new LinkedHashMap<>();
5045
5046 static {
5047 rewriters.put(argMismatchTemplate, new ArgMismatchRewriter(0));
5048 rewriters.put(inferArgMismatchTemplate, new ArgMismatchRewriter(1));
5049 }
5050
5051 /**
5052 * Main entry point for diagnostic rewriting - given a diagnostic, see if any templates matches it,
5053 * and rewrite it accordingly.
5054 */
5055 static JCDiagnostic rewrite(JCDiagnostic.Factory diags, DiagnosticPosition pos, DiagnosticSource source,
5056 DiagnosticType dkind, JCDiagnostic d) {
5057 for (Map.Entry<Template, DiagnosticRewriter> _entry : rewriters.entrySet()) {
5058 if (_entry.getKey().matches(d)) {
5059 JCDiagnostic simpleDiag =
5060 _entry.getValue().rewriteDiagnostic(diags, pos, source, dkind, d);
5061 simpleDiag.setFlag(DiagnosticFlag.COMPRESSED);
5062 return simpleDiag;
5063 }
5064 }
5065 return null;
5066 }
5067 }
5068
5069 enum MethodResolutionPhase {
5070 BASIC(false, false),
5071 BOX(true, false),
5072 VARARITY(true, true) {
5073 @Override
5074 public Symbol mergeResults(Symbol bestSoFar, Symbol sym) {
5075 //Check invariants (see {@code LookupHelper.shouldStop})
5076 Assert.check(bestSoFar.kind.isResolutionError() && bestSoFar.kind != AMBIGUOUS);
5077 if (!sym.kind.isResolutionError()) {
5078 //varargs resolution successful
5079 return sym;
5080 } else {
5081 //pick best error
5082 switch (bestSoFar.kind) {
5083 case WRONG_MTH:
5084 case WRONG_MTHS:
5085 //Override previous errors if they were caused by argument mismatch.
5086 //This generally means preferring current symbols - but we need to pay
5087 //attention to the fact that the varargs lookup returns 'less' candidates
5088 //than the previous rounds, and adjust that accordingly.
5089 switch (sym.kind) {
5090 case WRONG_MTH:
5091 //if the previous round matched more than one method, return that
5092 //result instead
5093 return bestSoFar.kind == WRONG_MTHS ?
5094 bestSoFar : sym;
5095 case ABSENT_MTH:
5096 //do not override erroneous symbol if the arity lookup did not
5097 //match any method
5098 return bestSoFar;
5099 case WRONG_MTHS:
5100 default:
5101 //safe to override
5102 return sym;
5103 }
5104 default:
5105 //otherwise, return first error
5106 return bestSoFar;
5107 }
5108 }
5109 }
5110 };
5111
5112 final boolean isBoxingRequired;
5113 final boolean isVarargsRequired;
5114
5115 MethodResolutionPhase(boolean isBoxingRequired, boolean isVarargsRequired) {
5116 this.isBoxingRequired = isBoxingRequired;
5117 this.isVarargsRequired = isVarargsRequired;
5118 }
5119
5120 public boolean isBoxingRequired() {
5121 return isBoxingRequired;
5122 }
5123
5124 public boolean isVarargsRequired() {
5125 return isVarargsRequired;
5126 }
5127
5128 public Symbol mergeResults(Symbol prev, Symbol sym) {
5129 return sym;
5130 }
5131 }
5132
5133 final List<MethodResolutionPhase> methodResolutionSteps = List.of(BASIC, BOX, VARARITY);
5134
5135 /**
5136 * A resolution context is used to keep track of intermediate results of
5137 * overload resolution, such as list of method that are not applicable
5138 * (used to generate more precise diagnostics) and so on. Resolution contexts
5139 * can be nested - this means that when each overload resolution routine should
5140 * work within the resolution context it created.
5141 */
5142 class MethodResolutionContext {
5143
5144 private List<Candidate> candidates = List.nil();
5145
5146 MethodResolutionPhase step = null;
5147
5148 MethodCheck methodCheck = resolveMethodCheck;
5149
5150 private boolean internalResolution = false;
5151 private DeferredAttr.AttrMode attrMode = DeferredAttr.AttrMode.SPECULATIVE;
5152
5153 void addInapplicableCandidate(Symbol sym, JCDiagnostic details) {
5154 Candidate c = new Candidate(currentResolutionContext.step, sym, details, null);
5155 candidates = candidates.append(c);
5156 }
5157
5158 void addApplicableCandidate(Symbol sym, Type mtype) {
5159 Candidate c = new Candidate(currentResolutionContext.step, sym, null, mtype);
5160 candidates = candidates.append(c);
5161 }
5162
5163 DeferredAttrContext deferredAttrContext(Symbol sym, InferenceContext inferenceContext, ResultInfo pendingResult, Warner warn) {
5164 DeferredAttrContext parent = (pendingResult == null)
5165 ? deferredAttr.emptyDeferredAttrContext
5166 : pendingResult.checkContext.deferredAttrContext();
5167 return deferredAttr.new DeferredAttrContext(attrMode, sym, step,
5168 inferenceContext, parent, warn);
5169 }
5170
5171 /**
5172 * This class represents an overload resolution candidate. There are two
5173 * kinds of candidates: applicable methods and inapplicable methods;
5174 * applicable methods have a pointer to the instantiated method type,
5175 * while inapplicable candidates contain further details about the
5176 * reason why the method has been considered inapplicable.
5177 */
5178 @SuppressWarnings("overrides")
5179 class Candidate {
5180
5181 final MethodResolutionPhase step;
5182 final Symbol sym;
5183 final JCDiagnostic details;
5184 final Type mtype;
5185
5186 private Candidate(MethodResolutionPhase step, Symbol sym, JCDiagnostic details, Type mtype) {
5187 this.step = step;
5188 this.sym = sym;
5189 this.details = details;
5190 this.mtype = mtype;
5191 }
5192
5193 boolean isApplicable() {
5194 return mtype != null;
5195 }
5196 }
5197
5198 DeferredAttr.AttrMode attrMode() {
5199 return attrMode;
5200 }
5201
5202 boolean internal() {
5203 return internalResolution;
5204 }
5205 }
5206
5207 MethodResolutionContext currentResolutionContext = null;
5208 }