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 ClassSymbol enclosingCsym = env.enclClass.sym;
423 try {
424 switch ((short)(sym.flags() & AccessFlags)) {
425 case PRIVATE:
426 return
427 (env.enclClass.sym == sym.owner // fast special case
428 ||
429 env.enclClass.sym.outermostClass() ==
430 sym.owner.outermostClass())
431 &&
432 sym.isInheritedIn(site.tsym, types);
433 case 0:
434 return
435 (env.toplevel.packge == sym.owner.owner // fast special case
436 ||
437 env.toplevel.packge == sym.packge())
438 &&
439 isAccessible(env, site, checkInner)
440 &&
441 sym.isInheritedIn(site.tsym, types)
442 &&
443 notOverriddenIn(site, sym);
444 case PROTECTED:
445 return
446 (env.toplevel.packge == sym.owner.owner // fast special case
447 ||
448 env.toplevel.packge == sym.packge()
449 ||
450 isProtectedAccessible(sym, env.enclClass.sym, site)
451 ||
452 // OK to select instance method or field from 'super' or type name
453 // (but type names should be disallowed elsewhere!)
454 env.info.selectSuper && (sym.flags() & STATIC) == 0 && sym.kind != TYP)
455 &&
456 isAccessible(env, site, checkInner)
457 &&
458 notOverriddenIn(site, sym);
459 default: // this case includes erroneous combinations as well
460 return isAccessible(env, site, checkInner) && notOverriddenIn(site, sym);
461 }
462 } finally {
463 env.enclClass.sym = enclosingCsym;
464 }
465 }
466 //where
467 /* `sym' is accessible only if not overridden by
468 * another symbol which is a member of `site'
469 * (because, if it is overridden, `sym' is not strictly
470 * speaking a member of `site'). A polymorphic signature method
471 * cannot be overridden (e.g. MH.invokeExact(Object[])).
472 */
473 private boolean notOverriddenIn(Type site, Symbol sym) {
474 if (sym.kind != MTH || sym.isConstructor() || sym.isStatic())
475 return true;
476 else {
477 Symbol s2 = ((MethodSymbol)sym).implementation(site.tsym, types, true);
478 return (s2 == null || s2 == sym || sym.owner == s2.owner || (sym.owner.isInterface() && s2.owner == syms.objectType.tsym) ||
479 !types.isSubSignature(types.memberType(site, s2), types.memberType(site, sym)));
480 }
481 }
482 //where
483 /** Is given protected symbol accessible if it is selected from given site
484 * and the selection takes place in given class?
485 * @param sym The symbol with protected access
486 * @param c The class where the access takes place
487 * @param site The type of the qualifier
488 */
489 private
490 boolean isProtectedAccessible(Symbol sym, ClassSymbol c, Type site) {
491 Type newSite = site.hasTag(TYPEVAR) ? site.getUpperBound() : site;
492 while (c != null &&
493 !(c.isSubClass(sym.owner, types) &&
494 (c.flags() & INTERFACE) == 0 &&
495 // In JLS 2e 6.6.2.1, the subclass restriction applies
496 // only to instance fields and methods -- types are excluded
497 // regardless of whether they are declared 'static' or not.
498 ((sym.flags() & STATIC) != 0 || sym.kind == TYP || newSite.tsym.isSubClass(c, types))))
499 c = c.owner.enclClass();
500 return c != null;
501 }
502
503 /**
504 * Performs a recursive scan of a type looking for accessibility problems
505 * from current attribution environment
506 */
507 void checkAccessibleType(Env<AttrContext> env, Type t) {
508 accessibilityChecker.visit(t, env);
509 }
510
511 /**
512 * Accessibility type-visitor
513 */
514 Types.SimpleVisitor<Void, Env<AttrContext>> accessibilityChecker =
515 new Types.SimpleVisitor<Void, Env<AttrContext>>() {
516
517 void visit(List<Type> ts, Env<AttrContext> env) {
518 for (Type t : ts) {
519 visit(t, env);
520 }
521 }
522
523 public Void visitType(Type t, Env<AttrContext> env) {
524 return null;
525 }
526
527 @Override
528 public Void visitArrayType(ArrayType t, Env<AttrContext> env) {
529 visit(t.elemtype, env);
530 return null;
531 }
532
533 @Override
534 public Void visitClassType(ClassType t, Env<AttrContext> env) {
535 visit(t.getTypeArguments(), env);
536 if (!isAccessible(env, t, true)) {
537 accessBase(new AccessError(env, null, t.tsym), env.tree.pos(), env.enclClass.sym, t, t.tsym.name, true);
538 }
539 return null;
540 }
541
542 @Override
543 public Void visitWildcardType(WildcardType t, Env<AttrContext> env) {
544 visit(t.type, env);
545 return null;
546 }
547
548 @Override
549 public Void visitMethodType(MethodType t, Env<AttrContext> env) {
550 visit(t.getParameterTypes(), env);
551 visit(t.getReturnType(), env);
552 visit(t.getThrownTypes(), env);
553 return null;
554 }
555 };
556
557 /** Try to instantiate the type of a method so that it fits
558 * given type arguments and argument types. If successful, return
559 * the method's instantiated type, else return null.
560 * The instantiation will take into account an additional leading
561 * formal parameter if the method is an instance method seen as a member
562 * of an under determined site. In this case, we treat site as an additional
563 * parameter and the parameters of the class containing the method as
564 * additional type variables that get instantiated.
565 *
566 * @param env The current environment
567 * @param site The type of which the method is a member.
568 * @param m The method symbol.
569 * @param argtypes The invocation's given value arguments.
570 * @param typeargtypes The invocation's given type arguments.
571 * @param allowBoxing Allow boxing conversions of arguments.
572 * @param useVarargs Box trailing arguments into an array for varargs.
573 */
574 Type rawInstantiate(Env<AttrContext> env,
575 Type site,
576 Symbol m,
577 ResultInfo resultInfo,
578 List<Type> argtypes,
579 List<Type> typeargtypes,
580 boolean allowBoxing,
581 boolean useVarargs,
582 Warner warn) throws Infer.InferenceException {
583 Type mt = types.memberType(site, m);
584 // tvars is the list of formal type variables for which type arguments
585 // need to inferred.
586 List<Type> tvars = List.nil();
587 if (typeargtypes == null) typeargtypes = List.nil();
588 if (!mt.hasTag(FORALL) && typeargtypes.nonEmpty()) {
589 // This is not a polymorphic method, but typeargs are supplied
590 // which is fine, see JLS 15.12.2.1
591 } else if (mt.hasTag(FORALL) && typeargtypes.nonEmpty()) {
592 ForAll pmt = (ForAll) mt;
593 if (typeargtypes.length() != pmt.tvars.length())
594 // not enough args
595 throw new InapplicableMethodException(diags.fragment(Fragments.WrongNumberTypeArgs(Integer.toString(pmt.tvars.length()))), dumpStacktraceOnError);
596 // Check type arguments are within bounds
597 List<Type> formals = pmt.tvars;
598 List<Type> actuals = typeargtypes;
599 while (formals.nonEmpty() && actuals.nonEmpty()) {
600 List<Type> bounds = types.subst(types.getBounds((TypeVar)formals.head),
601 pmt.tvars, typeargtypes);
602 for (; bounds.nonEmpty(); bounds = bounds.tail) {
603 if (!types.isSubtypeUnchecked(actuals.head, bounds.head, warn)) {
604 throw new InapplicableMethodException(diags.fragment(Fragments.ExplicitParamDoNotConformToBounds(actuals.head, bounds)), dumpStacktraceOnError);
605 }
606 }
607 formals = formals.tail;
608 actuals = actuals.tail;
609 }
610 mt = types.subst(pmt.qtype, pmt.tvars, typeargtypes);
611 } else if (mt.hasTag(FORALL)) {
612 ForAll pmt = (ForAll) mt;
613 List<Type> tvars1 = types.newInstances(pmt.tvars);
614 tvars = tvars.appendList(tvars1);
615 mt = types.subst(pmt.qtype, pmt.tvars, tvars1);
616 }
617
618 // find out whether we need to go the slow route via infer
619 boolean instNeeded = tvars.tail != null; /*inlined: tvars.nonEmpty()*/
620 for (List<Type> l = argtypes;
621 l.tail != null/*inlined: l.nonEmpty()*/ && !instNeeded;
622 l = l.tail) {
623 if (l.head.hasTag(FORALL)) instNeeded = true;
624 }
625
626 if (instNeeded) {
627 return infer.instantiateMethod(env,
628 tvars,
629 (MethodType)mt,
630 resultInfo,
631 (MethodSymbol)m,
632 argtypes,
633 allowBoxing,
634 useVarargs,
635 currentResolutionContext,
636 warn);
637 }
638
639 DeferredAttr.DeferredAttrContext dc = currentResolutionContext.deferredAttrContext(m, infer.emptyContext, resultInfo, warn);
640 currentResolutionContext.methodCheck.argumentsAcceptable(env, dc,
641 argtypes, mt.getParameterTypes(), warn);
642 dc.complete();
643 return mt;
644 }
645
646 Type checkMethod(Env<AttrContext> env,
647 Type site,
648 Symbol m,
649 ResultInfo resultInfo,
650 List<Type> argtypes,
651 List<Type> typeargtypes,
652 Warner warn) {
653 MethodResolutionContext prevContext = currentResolutionContext;
654 try {
655 currentResolutionContext = new MethodResolutionContext();
656 currentResolutionContext.attrMode = (resultInfo.pt == Infer.anyPoly) ?
657 AttrMode.SPECULATIVE : DeferredAttr.AttrMode.CHECK;
658 if (env.tree.hasTag(JCTree.Tag.REFERENCE)) {
659 //method/constructor references need special check class
660 //to handle inference variables in 'argtypes' (might happen
661 //during an unsticking round)
662 currentResolutionContext.methodCheck =
663 new MethodReferenceCheck(resultInfo.checkContext.inferenceContext());
664 }
665 MethodResolutionPhase step = currentResolutionContext.step = env.info.pendingResolutionPhase;
666 return rawInstantiate(env, site, m, resultInfo, argtypes, typeargtypes,
667 step.isBoxingRequired(), step.isVarargsRequired(), warn);
668 }
669 finally {
670 currentResolutionContext = prevContext;
671 }
672 }
673
674 /** Same but returns null instead throwing a NoInstanceException
675 */
676 Type instantiate(Env<AttrContext> env,
677 Type site,
678 Symbol m,
679 ResultInfo resultInfo,
680 List<Type> argtypes,
681 List<Type> typeargtypes,
682 boolean allowBoxing,
683 boolean useVarargs,
684 Warner warn) {
685 try {
686 return rawInstantiate(env, site, m, resultInfo, argtypes, typeargtypes,
687 allowBoxing, useVarargs, warn);
688 } catch (InapplicableMethodException ex) {
689 return null;
690 }
691 }
692
693 /**
694 * This interface defines an entry point that should be used to perform a
695 * method check. A method check usually consist in determining as to whether
696 * a set of types (actuals) is compatible with another set of types (formals).
697 * Since the notion of compatibility can vary depending on the circumstances,
698 * this interfaces allows to easily add new pluggable method check routines.
699 */
700 interface MethodCheck {
701 /**
702 * Main method check routine. A method check usually consist in determining
703 * as to whether a set of types (actuals) is compatible with another set of
704 * types (formals). If an incompatibility is found, an unchecked exception
705 * is assumed to be thrown.
706 */
707 void argumentsAcceptable(Env<AttrContext> env,
708 DeferredAttrContext deferredAttrContext,
709 List<Type> argtypes,
710 List<Type> formals,
711 Warner warn);
712
713 /**
714 * Retrieve the method check object that will be used during a
715 * most specific check.
716 */
717 MethodCheck mostSpecificCheck(List<Type> actuals);
718 }
719
720 /**
721 * Helper enum defining all method check diagnostics (used by resolveMethodCheck).
722 */
723 enum MethodCheckDiag {
724 /**
725 * Actuals and formals differs in length.
726 */
727 ARITY_MISMATCH("arg.length.mismatch", "infer.arg.length.mismatch"),
728 /**
729 * An actual is incompatible with a formal.
730 */
731 ARG_MISMATCH("no.conforming.assignment.exists", "infer.no.conforming.assignment.exists"),
732 /**
733 * An actual is incompatible with the varargs element type.
734 */
735 VARARG_MISMATCH("varargs.argument.mismatch", "infer.varargs.argument.mismatch"),
736 /**
737 * The varargs element type is inaccessible.
738 */
739 INACCESSIBLE_VARARGS("inaccessible.varargs.type", "inaccessible.varargs.type");
740
741 final String basicKey;
742 final String inferKey;
743
744 MethodCheckDiag(String basicKey, String inferKey) {
745 this.basicKey = basicKey;
746 this.inferKey = inferKey;
747 }
748
749 String regex() {
750 return String.format("([a-z]*\\.)*(%s|%s)", basicKey, inferKey);
751 }
752 }
753
754 /**
755 * Dummy method check object. All methods are deemed applicable, regardless
756 * of their formal parameter types.
757 */
758 MethodCheck nilMethodCheck = new MethodCheck() {
759 public void argumentsAcceptable(Env<AttrContext> env, DeferredAttrContext deferredAttrContext, List<Type> argtypes, List<Type> formals, Warner warn) {
760 //do nothing - method always applicable regardless of actuals
761 }
762
763 public MethodCheck mostSpecificCheck(List<Type> actuals) {
764 return this;
765 }
766 };
767
768 /**
769 * Base class for 'real' method checks. The class defines the logic for
770 * iterating through formals and actuals and provides and entry point
771 * that can be used by subclasses in order to define the actual check logic.
772 */
773 abstract class AbstractMethodCheck implements MethodCheck {
774 @Override
775 public void argumentsAcceptable(final Env<AttrContext> env,
776 DeferredAttrContext deferredAttrContext,
777 List<Type> argtypes,
778 List<Type> formals,
779 Warner warn) {
780 //should we expand formals?
781 boolean useVarargs = deferredAttrContext.phase.isVarargsRequired();
782 JCTree callTree = treeForDiagnostics(env);
783 List<JCExpression> trees = TreeInfo.args(callTree);
784
785 //inference context used during this method check
786 InferenceContext inferenceContext = deferredAttrContext.inferenceContext;
787
788 Type varargsFormal = useVarargs ? formals.last() : null;
789
790 if (varargsFormal == null &&
791 argtypes.size() != formals.size()) {
792 reportMC(callTree, MethodCheckDiag.ARITY_MISMATCH, inferenceContext); // not enough args
793 }
794
795 while (argtypes.nonEmpty() && formals.head != varargsFormal) {
796 DiagnosticPosition pos = trees != null ? trees.head : null;
797 checkArg(pos, false, argtypes.head, formals.head, deferredAttrContext, warn);
798 argtypes = argtypes.tail;
799 formals = formals.tail;
800 trees = trees != null ? trees.tail : trees;
801 }
802
803 if (formals.head != varargsFormal) {
804 reportMC(callTree, MethodCheckDiag.ARITY_MISMATCH, inferenceContext); // not enough args
805 }
806
807 if (useVarargs) {
808 //note: if applicability check is triggered by most specific test,
809 //the last argument of a varargs is _not_ an array type (see JLS 15.12.2.5)
810 final Type elt = types.elemtype(varargsFormal);
811 while (argtypes.nonEmpty()) {
812 DiagnosticPosition pos = trees != null ? trees.head : null;
813 checkArg(pos, true, argtypes.head, elt, deferredAttrContext, warn);
814 argtypes = argtypes.tail;
815 trees = trees != null ? trees.tail : trees;
816 }
817 }
818 }
819
820 // where
821 private JCTree treeForDiagnostics(Env<AttrContext> env) {
822 return env.info.preferredTreeForDiagnostics != null ? env.info.preferredTreeForDiagnostics : env.tree;
823 }
824
825 /**
826 * Does the actual argument conforms to the corresponding formal?
827 */
828 abstract void checkArg(DiagnosticPosition pos, boolean varargs, Type actual, Type formal, DeferredAttrContext deferredAttrContext, Warner warn);
829
830 protected void reportMC(DiagnosticPosition pos, MethodCheckDiag diag, InferenceContext inferenceContext, Object... args) {
831 boolean inferDiag = inferenceContext != infer.emptyContext;
832 if (inferDiag && (!diag.inferKey.equals(diag.basicKey))) {
833 Object[] args2 = new Object[args.length + 1];
834 System.arraycopy(args, 0, args2, 1, args.length);
835 args2[0] = inferenceContext.inferenceVars();
836 args = args2;
837 }
838 String key = inferDiag ? diag.inferKey : diag.basicKey;
839 throw inferDiag ?
840 infer.error(diags.create(DiagnosticType.FRAGMENT, log.currentSource(), pos, key, args)) :
841 getMethodCheckFailure().setMessage(diags.create(DiagnosticType.FRAGMENT, log.currentSource(), pos, key, args));
842 }
843
844 /**
845 * To eliminate the overhead associated with allocating an exception object in such an
846 * hot execution path, we use flyweight pattern - and share the same exception instance
847 * across multiple method check failures.
848 */
849 class SharedInapplicableMethodException extends InapplicableMethodException {
850 private static final long serialVersionUID = 0;
851
852 SharedInapplicableMethodException() {
853 super(null, Resolve.this.dumpStacktraceOnError);
854 }
855
856 SharedInapplicableMethodException setMessage(JCDiagnostic details) {
857 this.diagnostic = details;
858 return this;
859 }
860 }
861
862 private SharedInapplicableMethodException methodCheckFailure;
863
864 public MethodCheck mostSpecificCheck(List<Type> actuals) {
865 return nilMethodCheck;
866 }
867
868 private SharedInapplicableMethodException getMethodCheckFailure() {
869 return methodCheckFailure == null ? methodCheckFailure = new SharedInapplicableMethodException() : methodCheckFailure;
870 }
871 }
872
873 /**
874 * Arity-based method check. A method is applicable if the number of actuals
875 * supplied conforms to the method signature.
876 */
877 MethodCheck arityMethodCheck = new AbstractMethodCheck() {
878 @Override
879 void checkArg(DiagnosticPosition pos, boolean varargs, Type actual, Type formal, DeferredAttrContext deferredAttrContext, Warner warn) {
880 //do nothing - actual always compatible to formals
881 }
882
883 @Override
884 public String toString() {
885 return "arityMethodCheck";
886 }
887 };
888
889 /**
890 * Main method applicability routine. Given a list of actual types A,
891 * a list of formal types F, determines whether the types in A are
892 * compatible (by method invocation conversion) with the types in F.
893 *
894 * Since this routine is shared between overload resolution and method
895 * type-inference, a (possibly empty) inference context is used to convert
896 * formal types to the corresponding 'undet' form ahead of a compatibility
897 * check so that constraints can be propagated and collected.
898 *
899 * Moreover, if one or more types in A is a deferred type, this routine uses
900 * DeferredAttr in order to perform deferred attribution. If one or more actual
901 * deferred types are stuck, they are placed in a queue and revisited later
902 * after the remainder of the arguments have been seen. If this is not sufficient
903 * to 'unstuck' the argument, a cyclic inference error is called out.
904 *
905 * A method check handler (see above) is used in order to report errors.
906 */
907 MethodCheck resolveMethodCheck = new AbstractMethodCheck() {
908
909 @Override
910 void checkArg(DiagnosticPosition pos, boolean varargs, Type actual, Type formal, DeferredAttrContext deferredAttrContext, Warner warn) {
911 ResultInfo mresult = methodCheckResult(varargs, formal, deferredAttrContext, warn);
912 mresult.check(pos, actual);
913 }
914
915 @Override
916 public void argumentsAcceptable(final Env<AttrContext> env,
917 DeferredAttrContext deferredAttrContext,
918 List<Type> argtypes,
919 List<Type> formals,
920 Warner warn) {
921 super.argumentsAcceptable(env, deferredAttrContext, argtypes, formals, warn);
922 // should we check varargs element type accessibility?
923 if (deferredAttrContext.phase.isVarargsRequired()) {
924 if (deferredAttrContext.mode == AttrMode.CHECK) {
925 varargsAccessible(env, types.elemtype(formals.last()), deferredAttrContext.inferenceContext);
926 }
927 }
928 }
929
930 /**
931 * Test that the runtime array element type corresponding to 't' is accessible. 't' should be the
932 * varargs element type of either the method invocation type signature (after inference completes)
933 * or the method declaration signature (before inference completes).
934 */
935 private void varargsAccessible(final Env<AttrContext> env, final Type t, final InferenceContext inferenceContext) {
936 if (inferenceContext.free(t)) {
937 inferenceContext.addFreeTypeListener(List.of(t),
938 solvedContext -> varargsAccessible(env, solvedContext.asInstType(t), solvedContext));
939 } else {
940 if (!isAccessible(env, types.erasure(t))) {
941 Symbol location = env.enclClass.sym;
942 reportMC(env.tree, MethodCheckDiag.INACCESSIBLE_VARARGS, inferenceContext, t, Kinds.kindName(location), location);
943 }
944 }
945 }
946
947 private ResultInfo methodCheckResult(final boolean varargsCheck, Type to,
948 final DeferredAttr.DeferredAttrContext deferredAttrContext, Warner rsWarner) {
949 CheckContext checkContext = new MethodCheckContext(!deferredAttrContext.phase.isBoxingRequired(), deferredAttrContext, rsWarner) {
950 MethodCheckDiag methodDiag = varargsCheck ?
951 MethodCheckDiag.VARARG_MISMATCH : MethodCheckDiag.ARG_MISMATCH;
952
953 @Override
954 public void report(DiagnosticPosition pos, JCDiagnostic details) {
955 reportMC(pos, methodDiag, deferredAttrContext.inferenceContext, details);
956 }
957 };
958 return new MethodResultInfo(to, checkContext);
959 }
960
961 @Override
962 public MethodCheck mostSpecificCheck(List<Type> actuals) {
963 return new MostSpecificCheck(actuals);
964 }
965
966 @Override
967 public String toString() {
968 return "resolveMethodCheck";
969 }
970 };
971
972 /**
973 * This class handles method reference applicability checks; since during
974 * these checks it's sometime possible to have inference variables on
975 * the actual argument types list, the method applicability check must be
976 * extended so that inference variables are 'opened' as needed.
977 */
978 class MethodReferenceCheck extends AbstractMethodCheck {
979
980 InferenceContext pendingInferenceContext;
981
982 MethodReferenceCheck(InferenceContext pendingInferenceContext) {
983 this.pendingInferenceContext = pendingInferenceContext;
984 }
985
986 @Override
987 void checkArg(DiagnosticPosition pos, boolean varargs, Type actual, Type formal, DeferredAttrContext deferredAttrContext, Warner warn) {
988 ResultInfo mresult = methodCheckResult(varargs, formal, deferredAttrContext, warn);
989 mresult.check(pos, actual);
990 }
991
992 private ResultInfo methodCheckResult(final boolean varargsCheck, Type to,
993 final DeferredAttr.DeferredAttrContext deferredAttrContext, Warner rsWarner) {
994 CheckContext checkContext = new MethodCheckContext(!deferredAttrContext.phase.isBoxingRequired(), deferredAttrContext, rsWarner) {
995 MethodCheckDiag methodDiag = varargsCheck ?
996 MethodCheckDiag.VARARG_MISMATCH : MethodCheckDiag.ARG_MISMATCH;
997
998 @Override
999 public boolean compatible(Type found, Type req, Warner warn) {
1000 found = pendingInferenceContext.asUndetVar(found);
1001 if (found.hasTag(UNDETVAR) && req.isPrimitive()) {
1002 req = types.boxedClass(req).type;
1003 }
1004 return super.compatible(found, req, warn);
1005 }
1006
1007 @Override
1008 public void report(DiagnosticPosition pos, JCDiagnostic details) {
1009 reportMC(pos, methodDiag, deferredAttrContext.inferenceContext, details);
1010 }
1011 };
1012 return new MethodResultInfo(to, checkContext);
1013 }
1014
1015 @Override
1016 public MethodCheck mostSpecificCheck(List<Type> actuals) {
1017 return new MostSpecificCheck(actuals);
1018 }
1019
1020 @Override
1021 public String toString() {
1022 return "MethodReferenceCheck";
1023 }
1024 }
1025
1026 /**
1027 * Check context to be used during method applicability checks. A method check
1028 * context might contain inference variables.
1029 */
1030 abstract class MethodCheckContext implements CheckContext {
1031
1032 boolean strict;
1033 DeferredAttrContext deferredAttrContext;
1034 Warner rsWarner;
1035
1036 public MethodCheckContext(boolean strict, DeferredAttrContext deferredAttrContext, Warner rsWarner) {
1037 this.strict = strict;
1038 this.deferredAttrContext = deferredAttrContext;
1039 this.rsWarner = rsWarner;
1040 }
1041
1042 public boolean compatible(Type found, Type req, Warner warn) {
1043 InferenceContext inferenceContext = deferredAttrContext.inferenceContext;
1044 return strict ?
1045 types.isSubtypeUnchecked(inferenceContext.asUndetVar(found), inferenceContext.asUndetVar(req), warn) :
1046 types.isConvertible(inferenceContext.asUndetVar(found), inferenceContext.asUndetVar(req), warn);
1047 }
1048
1049 public void report(DiagnosticPosition pos, JCDiagnostic details) {
1050 throw new InapplicableMethodException(details, Resolve.this.dumpStacktraceOnError);
1051 }
1052
1053 public Warner checkWarner(DiagnosticPosition pos, Type found, Type req) {
1054 return rsWarner;
1055 }
1056
1057 public InferenceContext inferenceContext() {
1058 return deferredAttrContext.inferenceContext;
1059 }
1060
1061 public DeferredAttrContext deferredAttrContext() {
1062 return deferredAttrContext;
1063 }
1064
1065 @Override
1066 public String toString() {
1067 return "MethodCheckContext";
1068 }
1069 }
1070
1071 /**
1072 * ResultInfo class to be used during method applicability checks. Check
1073 * for deferred types goes through special path.
1074 */
1075 class MethodResultInfo extends ResultInfo {
1076
1077 public MethodResultInfo(Type pt, CheckContext checkContext) {
1078 attr.super(KindSelector.VAL, pt, checkContext);
1079 }
1080
1081 @Override
1082 protected Type check(DiagnosticPosition pos, Type found) {
1083 if (found.hasTag(DEFERRED)) {
1084 DeferredType dt = (DeferredType)found;
1085 return dt.check(this);
1086 } else {
1087 Type uResult = U(found);
1088 Type capturedType = pos == null || pos.getTree() == null ?
1089 types.capture(uResult) :
1090 checkContext.inferenceContext()
1091 .cachedCapture(pos.getTree(), uResult, true);
1092 return super.check(pos, chk.checkNonVoid(pos, capturedType));
1093 }
1094 }
1095
1096 /**
1097 * javac has a long-standing 'simplification' (see 6391995):
1098 * given an actual argument type, the method check is performed
1099 * on its upper bound. This leads to inconsistencies when an
1100 * argument type is checked against itself. For example, given
1101 * a type-variable T, it is not true that {@code U(T) <: T},
1102 * so we need to guard against that.
1103 */
1104 private Type U(Type found) {
1105 return found == pt ?
1106 found : types.cvarUpperBound(found);
1107 }
1108
1109 @Override
1110 protected MethodResultInfo dup(Type newPt) {
1111 return new MethodResultInfo(newPt, checkContext);
1112 }
1113
1114 @Override
1115 protected ResultInfo dup(CheckContext newContext) {
1116 return new MethodResultInfo(pt, newContext);
1117 }
1118
1119 @Override
1120 protected ResultInfo dup(Type newPt, CheckContext newContext) {
1121 return new MethodResultInfo(newPt, newContext);
1122 }
1123 }
1124
1125 /**
1126 * Most specific method applicability routine. Given a list of actual types A,
1127 * a list of formal types F1, and a list of formal types F2, the routine determines
1128 * as to whether the types in F1 can be considered more specific than those in F2 w.r.t.
1129 * argument types A.
1130 */
1131 class MostSpecificCheck implements MethodCheck {
1132
1133 List<Type> actuals;
1134
1135 MostSpecificCheck(List<Type> actuals) {
1136 this.actuals = actuals;
1137 }
1138
1139 @Override
1140 public void argumentsAcceptable(final Env<AttrContext> env,
1141 DeferredAttrContext deferredAttrContext,
1142 List<Type> formals1,
1143 List<Type> formals2,
1144 Warner warn) {
1145 formals2 = adjustArgs(formals2, deferredAttrContext.msym, formals1.length(), deferredAttrContext.phase.isVarargsRequired());
1146 while (formals2.nonEmpty()) {
1147 ResultInfo mresult = methodCheckResult(formals2.head, deferredAttrContext, warn, actuals.head);
1148 mresult.check(null, formals1.head);
1149 formals1 = formals1.tail;
1150 formals2 = formals2.tail;
1151 actuals = actuals.isEmpty() ? actuals : actuals.tail;
1152 }
1153 }
1154
1155 /**
1156 * Create a method check context to be used during the most specific applicability check
1157 */
1158 ResultInfo methodCheckResult(Type to, DeferredAttr.DeferredAttrContext deferredAttrContext,
1159 Warner rsWarner, Type actual) {
1160 return attr.new ResultInfo(KindSelector.VAL, to,
1161 new MostSpecificCheckContext(deferredAttrContext, rsWarner, actual));
1162 }
1163
1164 /**
1165 * Subclass of method check context class that implements most specific
1166 * method conversion. If the actual type under analysis is a deferred type
1167 * a full blown structural analysis is carried out.
1168 */
1169 class MostSpecificCheckContext extends MethodCheckContext {
1170
1171 Type actual;
1172
1173 public MostSpecificCheckContext(DeferredAttrContext deferredAttrContext, Warner rsWarner, Type actual) {
1174 super(true, deferredAttrContext, rsWarner);
1175 this.actual = actual;
1176 }
1177
1178 public boolean compatible(Type found, Type req, Warner warn) {
1179 if (unrelatedFunctionalInterfaces(found, req) &&
1180 (actual != null && actual.getTag() == DEFERRED)) {
1181 DeferredType dt = (DeferredType) actual;
1182 JCTree speculativeTree = dt.speculativeTree(deferredAttrContext);
1183 if (speculativeTree != deferredAttr.stuckTree) {
1184 return functionalInterfaceMostSpecific(found, req, speculativeTree);
1185 }
1186 }
1187 return compatibleBySubtyping(found, req);
1188 }
1189
1190 private boolean compatibleBySubtyping(Type found, Type req) {
1191 if (!strict && found.isPrimitive() != req.isPrimitive()) {
1192 found = found.isPrimitive() ? types.boxedClass(found).type : types.unboxedType(found);
1193 }
1194 return types.isSubtypeNoCapture(found, deferredAttrContext.inferenceContext.asUndetVar(req));
1195 }
1196
1197 /** Whether {@code t} and {@code s} are unrelated functional interface types. */
1198 private boolean unrelatedFunctionalInterfaces(Type t, Type s) {
1199 return types.isFunctionalInterface(t.tsym) &&
1200 types.isFunctionalInterface(s.tsym) &&
1201 unrelatedInterfaces(t, s);
1202 }
1203
1204 /** Whether {@code t} and {@code s} are unrelated interface types; recurs on intersections. **/
1205 private boolean unrelatedInterfaces(Type t, Type s) {
1206 if (t.isCompound()) {
1207 for (Type ti : types.interfaces(t)) {
1208 if (!unrelatedInterfaces(ti, s)) {
1209 return false;
1210 }
1211 }
1212 return true;
1213 } else if (s.isCompound()) {
1214 for (Type si : types.interfaces(s)) {
1215 if (!unrelatedInterfaces(t, si)) {
1216 return false;
1217 }
1218 }
1219 return true;
1220 } else {
1221 return types.asSuper(t, s.tsym) == null && types.asSuper(s, t.tsym) == null;
1222 }
1223 }
1224
1225 /** Parameters {@code t} and {@code s} are unrelated functional interface types. */
1226 private boolean functionalInterfaceMostSpecific(Type t, Type s, JCTree tree) {
1227 Type tDesc;
1228 Type tDescNoCapture;
1229 Type sDesc;
1230 try {
1231 tDesc = types.findDescriptorType(types.capture(t));
1232 tDescNoCapture = types.findDescriptorType(t);
1233 sDesc = types.findDescriptorType(s);
1234 } catch (Types.FunctionDescriptorLookupError ex) {
1235 // don't report, a more meaningful error should be reported upstream
1236 return false;
1237 }
1238 final List<Type> tTypeParams = tDesc.getTypeArguments();
1239 final List<Type> tTypeParamsNoCapture = tDescNoCapture.getTypeArguments();
1240 final List<Type> sTypeParams = sDesc.getTypeArguments();
1241
1242 // compare type parameters
1243 if (tDesc.hasTag(FORALL) && !types.hasSameBounds((ForAll) tDesc, (ForAll) tDescNoCapture)) {
1244 return false;
1245 }
1246 // can't use Types.hasSameBounds on sDesc because bounds may have ivars
1247 List<Type> tIter = tTypeParams;
1248 List<Type> sIter = sTypeParams;
1249 while (tIter.nonEmpty() && sIter.nonEmpty()) {
1250 Type tBound = tIter.head.getUpperBound();
1251 Type sBound = types.subst(sIter.head.getUpperBound(), sTypeParams, tTypeParams);
1252 if (tBound.containsAny(tTypeParams) && inferenceContext().free(sBound)) {
1253 return false;
1254 }
1255 if (!types.isSameType(tBound, inferenceContext().asUndetVar(sBound))) {
1256 return false;
1257 }
1258 tIter = tIter.tail;
1259 sIter = sIter.tail;
1260 }
1261 if (!tIter.isEmpty() || !sIter.isEmpty()) {
1262 return false;
1263 }
1264
1265 // compare parameters
1266 List<Type> tParams = tDesc.getParameterTypes();
1267 List<Type> tParamsNoCapture = tDescNoCapture.getParameterTypes();
1268 List<Type> sParams = sDesc.getParameterTypes();
1269 while (tParams.nonEmpty() && tParamsNoCapture.nonEmpty() && sParams.nonEmpty()) {
1270 Type tParam = tParams.head;
1271 Type tParamNoCapture = types.subst(tParamsNoCapture.head, tTypeParamsNoCapture, tTypeParams);
1272 Type sParam = types.subst(sParams.head, sTypeParams, tTypeParams);
1273 if (tParam.containsAny(tTypeParams) && inferenceContext().free(sParam)) {
1274 return false;
1275 }
1276 if (!types.isSubtype(inferenceContext().asUndetVar(sParam), tParam)) {
1277 return false;
1278 }
1279 if (!types.isSameType(tParamNoCapture, inferenceContext().asUndetVar(sParam))) {
1280 return false;
1281 }
1282 tParams = tParams.tail;
1283 tParamsNoCapture = tParamsNoCapture.tail;
1284 sParams = sParams.tail;
1285 }
1286 if (!tParams.isEmpty() || !tParamsNoCapture.isEmpty() || !sParams.isEmpty()) {
1287 return false;
1288 }
1289
1290 // compare returns
1291 Type tRet = tDesc.getReturnType();
1292 Type sRet = types.subst(sDesc.getReturnType(), sTypeParams, tTypeParams);
1293 if (tRet.containsAny(tTypeParams) && inferenceContext().free(sRet)) {
1294 return false;
1295 }
1296 MostSpecificFunctionReturnChecker msc = new MostSpecificFunctionReturnChecker(tRet, sRet);
1297 msc.scan(tree);
1298 return msc.result;
1299 }
1300
1301 /**
1302 * Tests whether one functional interface type can be considered more specific
1303 * than another unrelated functional interface type for the scanned expression.
1304 */
1305 class MostSpecificFunctionReturnChecker extends DeferredAttr.PolyScanner {
1306
1307 final Type tRet;
1308 final Type sRet;
1309 boolean result;
1310
1311 /** Parameters {@code t} and {@code s} are unrelated functional interface types. */
1312 MostSpecificFunctionReturnChecker(Type tRet, Type sRet) {
1313 this.tRet = tRet;
1314 this.sRet = sRet;
1315 result = true;
1316 }
1317
1318 @Override
1319 void skip(JCTree tree) {
1320 result = false;
1321 }
1322
1323 @Override
1324 public void visitConditional(JCConditional tree) {
1325 scan(asExpr(tree.truepart));
1326 scan(asExpr(tree.falsepart));
1327 }
1328
1329 @Override
1330 public void visitReference(JCMemberReference tree) {
1331 if (sRet.hasTag(VOID)) {
1332 // do nothing
1333 } else if (tRet.hasTag(VOID)) {
1334 result = false;
1335 } else if (tRet.isPrimitive() != sRet.isPrimitive()) {
1336 boolean retValIsPrimitive =
1337 tree.refPolyKind == PolyKind.STANDALONE &&
1338 tree.sym.type.getReturnType().isPrimitive();
1339 result &= (retValIsPrimitive == tRet.isPrimitive()) &&
1340 (retValIsPrimitive != sRet.isPrimitive());
1341 } else {
1342 result &= compatibleBySubtyping(tRet, sRet);
1343 }
1344 }
1345
1346 @Override
1347 public void visitParens(JCParens tree) {
1348 scan(asExpr(tree.expr));
1349 }
1350
1351 @Override
1352 public void visitLambda(JCLambda tree) {
1353 if (sRet.hasTag(VOID)) {
1354 // do nothing
1355 } else if (tRet.hasTag(VOID)) {
1356 result = false;
1357 } else {
1358 List<JCExpression> lambdaResults = lambdaResults(tree);
1359 if (!lambdaResults.isEmpty() && unrelatedFunctionalInterfaces(tRet, sRet)) {
1360 for (JCExpression expr : lambdaResults) {
1361 result &= functionalInterfaceMostSpecific(tRet, sRet, expr);
1362 }
1363 } else if (!lambdaResults.isEmpty() && tRet.isPrimitive() != sRet.isPrimitive()) {
1364 for (JCExpression expr : lambdaResults) {
1365 boolean retValIsPrimitive = expr.isStandalone() && expr.type.isPrimitive();
1366 result &= (retValIsPrimitive == tRet.isPrimitive()) &&
1367 (retValIsPrimitive != sRet.isPrimitive());
1368 }
1369 } else {
1370 result &= compatibleBySubtyping(tRet, sRet);
1371 }
1372 }
1373 }
1374 //where
1375
1376 private List<JCExpression> lambdaResults(JCLambda lambda) {
1377 if (lambda.getBodyKind() == JCTree.JCLambda.BodyKind.EXPRESSION) {
1378 return List.of(asExpr((JCExpression) lambda.body));
1379 } else {
1380 final ListBuffer<JCExpression> buffer = new ListBuffer<>();
1381 DeferredAttr.LambdaReturnScanner lambdaScanner =
1382 new DeferredAttr.LambdaReturnScanner() {
1383 @Override
1384 public void visitReturn(JCReturn tree) {
1385 if (tree.expr != null) {
1386 buffer.append(asExpr(tree.expr));
1387 }
1388 }
1389 };
1390 lambdaScanner.scan(lambda.body);
1391 return buffer.toList();
1392 }
1393 }
1394
1395 private JCExpression asExpr(JCExpression expr) {
1396 if (expr.type.hasTag(DEFERRED)) {
1397 JCTree speculativeTree = ((DeferredType)expr.type).speculativeTree(deferredAttrContext);
1398 if (speculativeTree != deferredAttr.stuckTree) {
1399 expr = (JCExpression)speculativeTree;
1400 }
1401 }
1402 return expr;
1403 }
1404 }
1405
1406 }
1407
1408 public MethodCheck mostSpecificCheck(List<Type> actuals) {
1409 Assert.error("Cannot get here!");
1410 return null;
1411 }
1412 }
1413
1414 public static class InapplicableMethodException extends CompilerInternalException {
1415 private static final long serialVersionUID = 0;
1416
1417 transient JCDiagnostic diagnostic;
1418
1419 InapplicableMethodException(JCDiagnostic diag, boolean dumpStackTraceOnError) {
1420 super(dumpStackTraceOnError);
1421 this.diagnostic = diag;
1422 }
1423
1424 public JCDiagnostic getDiagnostic() {
1425 return diagnostic;
1426 }
1427 }
1428
1429 /* ***************************************************************************
1430 * Symbol lookup
1431 * the following naming conventions for arguments are used
1432 *
1433 * env is the environment where the symbol was mentioned
1434 * site is the type of which the symbol is a member
1435 * name is the symbol's name
1436 * if no arguments are given
1437 * argtypes are the value arguments, if we search for a method
1438 *
1439 * If no symbol was found, a ResolveError detailing the problem is returned.
1440 ****************************************************************************/
1441
1442 /** Find field. Synthetic fields are always skipped.
1443 * @param env The current environment.
1444 * @param site The original type from where the selection takes place.
1445 * @param name The name of the field.
1446 * @param c The class to search for the field. This is always
1447 * a superclass or implemented interface of site's class.
1448 */
1449 Symbol findField(Env<AttrContext> env,
1450 Type site,
1451 Name name,
1452 TypeSymbol c) {
1453 while (c.type.hasTag(TYPEVAR))
1454 c = c.type.getUpperBound().tsym;
1455 Symbol bestSoFar = varNotFound;
1456 Symbol sym;
1457 for (Symbol s : c.members().getSymbolsByName(name)) {
1458 if (s.kind == VAR && (s.flags_field & SYNTHETIC) == 0) {
1459 return isAccessible(env, site, s)
1460 ? s : new AccessError(env, site, s);
1461 }
1462 }
1463 Type st = types.supertype(c.type);
1464 if (st != null && (st.hasTag(CLASS) || st.hasTag(TYPEVAR))) {
1465 sym = findField(env, site, name, st.tsym);
1466 bestSoFar = bestOf(bestSoFar, sym);
1467 }
1468 for (List<Type> l = types.interfaces(c.type);
1469 bestSoFar.kind != AMBIGUOUS && l.nonEmpty();
1470 l = l.tail) {
1471 sym = findField(env, site, name, l.head.tsym);
1472 if (bestSoFar.exists() && sym.exists() &&
1473 sym.owner != bestSoFar.owner)
1474 bestSoFar = new AmbiguityError(bestSoFar, sym);
1475 else
1476 bestSoFar = bestOf(bestSoFar, sym);
1477 }
1478 return bestSoFar;
1479 }
1480
1481 /** Resolve a field identifier, throw a fatal error if not found.
1482 * @param pos The position to use for error reporting.
1483 * @param env The environment current at the method invocation.
1484 * @param site The type of the qualifying expression, in which
1485 * identifier is searched.
1486 * @param name The identifier's name.
1487 */
1488 public VarSymbol resolveInternalField(DiagnosticPosition pos, Env<AttrContext> env,
1489 Type site, Name name) {
1490 Symbol sym = findField(env, site, name, site.tsym);
1491 if (sym.kind == VAR) return (VarSymbol)sym;
1492 else throw new FatalError(
1493 diags.fragment(Fragments.FatalErrCantLocateField(name)));
1494 }
1495
1496 /** Find unqualified variable or field with given name.
1497 * Synthetic fields always skipped.
1498 * @param pos The position to use for error reporting.
1499 * @param env The current environment.
1500 * @param name The name of the variable or field.
1501 */
1502 Symbol findVar(DiagnosticPosition pos, Env<AttrContext> env, Name name) {
1503 Symbol bestSoFar = varNotFound;
1504 Env<AttrContext> env1 = env;
1505 boolean staticOnly = false;
1506 while (env1.outer != null) {
1507 Symbol sym = null;
1508 for (Symbol s : env1.info.scope.getSymbolsByName(name)) {
1509 if (s.kind == VAR && (s.flags_field & SYNTHETIC) == 0) {
1510 sym = s;
1511 if (staticOnly) {
1512 return new StaticError(sym);
1513 }
1514 break;
1515 }
1516 }
1517 if (isStatic(env1)) staticOnly = true;
1518 if (sym == null) {
1519 sym = findField(env1, env1.enclClass.sym.type, name, env1.enclClass.sym);
1520 }
1521 if (sym.exists()) {
1522 if (sym.kind == VAR &&
1523 sym.owner.kind == TYP &&
1524 (sym.flags() & STATIC) == 0) {
1525 if (staticOnly)
1526 return new StaticError(sym);
1527 if (env1.info.ctorPrologue && !isAllowedEarlyReference(pos, env1, (VarSymbol)sym)) {
1528 if (!env.tree.hasTag(ASSIGN) || !TreeInfo.isIdentOrThisDotIdent(((JCAssign)env.tree).lhs)) {
1529 return new RefBeforeCtorCalledError(sym);
1530 }
1531 }
1532 }
1533 return sym;
1534 } else {
1535 bestSoFar = bestOf(bestSoFar, sym);
1536 }
1537
1538 if ((env1.enclClass.sym.flags() & STATIC) != 0) staticOnly = true;
1539 env1 = env1.outer;
1540 }
1541
1542 Symbol sym = findField(env, syms.predefClass.type, name, syms.predefClass);
1543 if (sym.exists())
1544 return sym;
1545 if (bestSoFar.exists())
1546 return bestSoFar;
1547
1548 Symbol origin = null;
1549 for (Scope sc : new Scope[] { env.toplevel.namedImportScope, env.toplevel.starImportScope }) {
1550 for (Symbol currentSymbol : sc.getSymbolsByName(name)) {
1551 if (currentSymbol.kind != VAR)
1552 continue;
1553 // invariant: sym.kind == Symbol.Kind.VAR
1554 if (!bestSoFar.kind.isResolutionError() &&
1555 currentSymbol.owner != bestSoFar.owner)
1556 return new AmbiguityError(bestSoFar, currentSymbol);
1557 else if (!bestSoFar.kind.betterThan(VAR)) {
1558 origin = sc.getOrigin(currentSymbol).owner;
1559 bestSoFar = isAccessible(env, origin.type, currentSymbol)
1560 ? currentSymbol : new AccessError(env, origin.type, currentSymbol);
1561 }
1562 }
1563 if (bestSoFar.exists()) break;
1564 }
1565 if (bestSoFar.kind == VAR && bestSoFar.owner.type != origin.type)
1566 return bestSoFar.clone(origin);
1567 else
1568 return bestSoFar;
1569 }
1570
1571 Warner noteWarner = new Warner();
1572
1573 /** Select the best method for a call site among two choices.
1574 * @param env The current environment.
1575 * @param site The original type from where the
1576 * selection takes place.
1577 * @param argtypes The invocation's value arguments,
1578 * @param typeargtypes The invocation's type arguments,
1579 * @param sym Proposed new best match.
1580 * @param bestSoFar Previously found best match.
1581 * @param allowBoxing Allow boxing conversions of arguments.
1582 * @param useVarargs Box trailing arguments into an array for varargs.
1583 */
1584 @SuppressWarnings("fallthrough")
1585 Symbol selectBest(Env<AttrContext> env,
1586 Type site,
1587 List<Type> argtypes,
1588 List<Type> typeargtypes,
1589 Symbol sym,
1590 Symbol bestSoFar,
1591 boolean allowBoxing,
1592 boolean useVarargs) {
1593 if (sym.kind == ERR ||
1594 (site.tsym != sym.owner && !sym.isInheritedIn(site.tsym, types)) ||
1595 !notOverriddenIn(site, sym)) {
1596 return bestSoFar;
1597 } else if (useVarargs && (sym.flags() & VARARGS) == 0) {
1598 return bestSoFar.kind.isResolutionError() ?
1599 new BadVarargsMethod((ResolveError)bestSoFar.baseSymbol()) :
1600 bestSoFar;
1601 }
1602 Assert.check(!sym.kind.isResolutionError());
1603 try {
1604 types.noWarnings.clear();
1605 Type mt = rawInstantiate(env, site, sym, null, argtypes, typeargtypes,
1606 allowBoxing, useVarargs, types.noWarnings);
1607 currentResolutionContext.addApplicableCandidate(sym, mt);
1608 } catch (InapplicableMethodException ex) {
1609 currentResolutionContext.addInapplicableCandidate(sym, ex.getDiagnostic());
1610 // Currently, an InapplicableMethodException occurs.
1611 // If bestSoFar.kind was ABSENT_MTH, return an InapplicableSymbolError(kind is WRONG_MTH).
1612 // If bestSoFar.kind was HIDDEN(AccessError)/WRONG_MTH/WRONG_MTHS, return an InapplicableSymbolsError(kind is WRONG_MTHS).
1613 // See JDK-8255968 for more information.
1614 switch (bestSoFar.kind) {
1615 case ABSENT_MTH:
1616 return new InapplicableSymbolError(currentResolutionContext);
1617 case HIDDEN:
1618 if (bestSoFar instanceof AccessError accessError) {
1619 // Add the JCDiagnostic of previous AccessError to the currentResolutionContext
1620 // and construct InapplicableSymbolsError.
1621 // Intentionally fallthrough.
1622 currentResolutionContext.addInapplicableCandidate(accessError.sym,
1623 accessError.getDiagnostic(JCDiagnostic.DiagnosticType.FRAGMENT, null, null, site, null, argtypes, typeargtypes));
1624 } else {
1625 return bestSoFar;
1626 }
1627 case WRONG_MTH:
1628 bestSoFar = new InapplicableSymbolsError(currentResolutionContext);
1629 default:
1630 return bestSoFar;
1631 }
1632 }
1633 if (!isAccessible(env, site, sym)) {
1634 AccessError curAccessError = new AccessError(env, site, sym);
1635 JCDiagnostic curDiagnostic = curAccessError.getDiagnostic(JCDiagnostic.DiagnosticType.FRAGMENT, null, null, site, null, argtypes, typeargtypes);
1636 // Currently, an AccessError occurs.
1637 // If bestSoFar.kind was ABSENT_MTH, return an AccessError(kind is HIDDEN).
1638 // If bestSoFar.kind was HIDDEN(AccessError), WRONG_MTH, WRONG_MTHS, return an InapplicableSymbolsError(kind is WRONG_MTHS).
1639 // See JDK-8255968 for more information.
1640 if (bestSoFar.kind == ABSENT_MTH) {
1641 bestSoFar = curAccessError;
1642 } else if (bestSoFar.kind == WRONG_MTH) {
1643 // Add the JCDiagnostic of current AccessError to the currentResolutionContext
1644 // and construct InapplicableSymbolsError.
1645 currentResolutionContext.addInapplicableCandidate(sym, curDiagnostic);
1646 bestSoFar = new InapplicableSymbolsError(currentResolutionContext);
1647 } else if (bestSoFar.kind == WRONG_MTHS) {
1648 // Add the JCDiagnostic of current AccessError to the currentResolutionContext
1649 currentResolutionContext.addInapplicableCandidate(sym, curDiagnostic);
1650 } else if (bestSoFar.kind == HIDDEN && bestSoFar instanceof AccessError accessError) {
1651 // Add the JCDiagnostics of previous and current AccessError to the currentResolutionContext
1652 // and construct InapplicableSymbolsError.
1653 currentResolutionContext.addInapplicableCandidate(accessError.sym,
1654 accessError.getDiagnostic(JCDiagnostic.DiagnosticType.FRAGMENT, null, null, site, null, argtypes, typeargtypes));
1655 currentResolutionContext.addInapplicableCandidate(sym, curDiagnostic);
1656 bestSoFar = new InapplicableSymbolsError(currentResolutionContext);
1657 }
1658 return bestSoFar;
1659 }
1660 return (bestSoFar.kind.isResolutionError() && bestSoFar.kind != AMBIGUOUS)
1661 ? sym
1662 : mostSpecific(argtypes, sym, bestSoFar, env, site, useVarargs);
1663 }
1664
1665 /* Return the most specific of the two methods for a call,
1666 * given that both are accessible and applicable.
1667 * @param m1 A new candidate for most specific.
1668 * @param m2 The previous most specific candidate.
1669 * @param env The current environment.
1670 * @param site The original type from where the selection
1671 * takes place.
1672 * @param allowBoxing Allow boxing conversions of arguments.
1673 * @param useVarargs Box trailing arguments into an array for varargs.
1674 */
1675 Symbol mostSpecific(List<Type> argtypes, Symbol m1,
1676 Symbol m2,
1677 Env<AttrContext> env,
1678 final Type site,
1679 boolean useVarargs) {
1680 switch (m2.kind) {
1681 case MTH:
1682 if (m1 == m2) return m1;
1683 boolean m1SignatureMoreSpecific =
1684 signatureMoreSpecific(argtypes, env, site, m1, m2, useVarargs);
1685 boolean m2SignatureMoreSpecific =
1686 signatureMoreSpecific(argtypes, env, site, m2, m1, useVarargs);
1687 if (m1SignatureMoreSpecific && m2SignatureMoreSpecific) {
1688 Type mt1 = types.memberType(site, m1);
1689 Type mt2 = types.memberType(site, m2);
1690 if (!types.overrideEquivalent(mt1, mt2))
1691 return ambiguityError(m1, m2);
1692
1693 // same signature; select (a) the non-bridge method, or
1694 // (b) the one that overrides the other, or (c) the concrete
1695 // one, or (d) merge both abstract signatures
1696 if ((m1.flags() & BRIDGE) != (m2.flags() & BRIDGE))
1697 return ((m1.flags() & BRIDGE) != 0) ? m2 : m1;
1698
1699 if (m1.baseSymbol() == m2.baseSymbol()) {
1700 // this is the same imported symbol which has been cloned twice.
1701 // Return the first one (either will do).
1702 return m1;
1703 }
1704
1705 // if one overrides or hides the other, use it
1706 TypeSymbol m1Owner = (TypeSymbol)m1.owner;
1707 TypeSymbol m2Owner = (TypeSymbol)m2.owner;
1708 // the two owners can never be the same if the target methods are compiled from source,
1709 // but we need to protect against cases where the methods are defined in some classfile
1710 // and make sure we issue an ambiguity error accordingly (by skipping the logic below).
1711 if (m1Owner != m2Owner) {
1712 if (types.asSuper(m1Owner.type, m2Owner) != null &&
1713 ((m1.owner.flags_field & INTERFACE) == 0 ||
1714 (m2.owner.flags_field & INTERFACE) != 0) &&
1715 m1.overrides(m2, m1Owner, types, false))
1716 return m1;
1717 if (types.asSuper(m2Owner.type, m1Owner) != null &&
1718 ((m2.owner.flags_field & INTERFACE) == 0 ||
1719 (m1.owner.flags_field & INTERFACE) != 0) &&
1720 m2.overrides(m1, m2Owner, types, false))
1721 return m2;
1722 }
1723 boolean m1Abstract = (m1.flags() & ABSTRACT) != 0;
1724 boolean m2Abstract = (m2.flags() & ABSTRACT) != 0;
1725 if (m1Abstract && !m2Abstract) return m2;
1726 if (m2Abstract && !m1Abstract) return m1;
1727 // both abstract or both concrete
1728 return ambiguityError(m1, m2);
1729 }
1730 if (m1SignatureMoreSpecific) return m1;
1731 if (m2SignatureMoreSpecific) return m2;
1732 return ambiguityError(m1, m2);
1733 case AMBIGUOUS:
1734 //compare m1 to ambiguous methods in m2
1735 AmbiguityError e = (AmbiguityError)m2.baseSymbol();
1736 boolean m1MoreSpecificThanAnyAmbiguous = true;
1737 boolean allAmbiguousMoreSpecificThanM1 = true;
1738 for (Symbol s : e.ambiguousSyms) {
1739 Symbol moreSpecific = mostSpecific(argtypes, m1, s, env, site, useVarargs);
1740 m1MoreSpecificThanAnyAmbiguous &= moreSpecific == m1;
1741 allAmbiguousMoreSpecificThanM1 &= moreSpecific == s;
1742 }
1743 if (m1MoreSpecificThanAnyAmbiguous)
1744 return m1;
1745 //if m1 is more specific than some ambiguous methods, but other ambiguous methods are
1746 //more specific than m1, add it as a new ambiguous method:
1747 if (!allAmbiguousMoreSpecificThanM1)
1748 e.addAmbiguousSymbol(m1);
1749 return e;
1750 default:
1751 throw new AssertionError();
1752 }
1753 }
1754 //where
1755 private boolean signatureMoreSpecific(List<Type> actuals, Env<AttrContext> env, Type site, Symbol m1, Symbol m2, boolean useVarargs) {
1756 noteWarner.clear();
1757 int maxLength = Math.max(
1758 Math.max(m1.type.getParameterTypes().length(), actuals.length()),
1759 m2.type.getParameterTypes().length());
1760 MethodResolutionContext prevResolutionContext = currentResolutionContext;
1761 try {
1762 currentResolutionContext = new MethodResolutionContext();
1763 currentResolutionContext.step = prevResolutionContext.step;
1764 currentResolutionContext.methodCheck =
1765 prevResolutionContext.methodCheck.mostSpecificCheck(actuals);
1766 Type mst = instantiate(env, site, m2, null,
1767 adjustArgs(types.cvarLowerBounds(types.memberType(site, m1).getParameterTypes()), m1, maxLength, useVarargs), null,
1768 false, useVarargs, noteWarner);
1769 return mst != null &&
1770 !noteWarner.hasLint(Lint.LintCategory.UNCHECKED);
1771 } finally {
1772 currentResolutionContext = prevResolutionContext;
1773 }
1774 }
1775
1776 List<Type> adjustArgs(List<Type> args, Symbol msym, int length, boolean allowVarargs) {
1777 if ((msym.flags() & VARARGS) != 0 && allowVarargs) {
1778 Type varargsElem = types.elemtype(args.last());
1779 if (varargsElem == null) {
1780 Assert.error("Bad varargs = " + args.last() + " " + msym);
1781 }
1782 List<Type> newArgs = args.reverse().tail.prepend(varargsElem).reverse();
1783 while (newArgs.length() < length) {
1784 newArgs = newArgs.append(newArgs.last());
1785 }
1786 return newArgs;
1787 } else {
1788 return args;
1789 }
1790 }
1791 //where
1792 Symbol ambiguityError(Symbol m1, Symbol m2) {
1793 if (((m1.flags() | m2.flags()) & CLASH) != 0) {
1794 return (m1.flags() & CLASH) == 0 ? m1 : m2;
1795 } else {
1796 return new AmbiguityError(m1, m2);
1797 }
1798 }
1799
1800 Symbol findMethodInScope(Env<AttrContext> env,
1801 Type site,
1802 Name name,
1803 List<Type> argtypes,
1804 List<Type> typeargtypes,
1805 Scope sc,
1806 Symbol bestSoFar,
1807 boolean allowBoxing,
1808 boolean useVarargs,
1809 boolean abstractok) {
1810 for (Symbol s : sc.getSymbolsByName(name, new LookupFilter(abstractok))) {
1811 bestSoFar = selectBest(env, site, argtypes, typeargtypes, s,
1812 bestSoFar, allowBoxing, useVarargs);
1813 }
1814 return bestSoFar;
1815 }
1816 //where
1817 class LookupFilter implements Predicate<Symbol> {
1818
1819 boolean abstractOk;
1820
1821 LookupFilter(boolean abstractOk) {
1822 this.abstractOk = abstractOk;
1823 }
1824
1825 @Override
1826 public boolean test(Symbol s) {
1827 long flags = s.flags();
1828 return s.kind == MTH &&
1829 (flags & SYNTHETIC) == 0 &&
1830 (abstractOk ||
1831 (flags & DEFAULT) != 0 ||
1832 (flags & ABSTRACT) == 0);
1833 }
1834 }
1835
1836 /** Find best qualified method matching given name, type and value
1837 * arguments.
1838 * @param env The current environment.
1839 * @param site The original type from where the selection
1840 * takes place.
1841 * @param name The method's name.
1842 * @param argtypes The method's value arguments.
1843 * @param typeargtypes The method's type arguments
1844 * @param allowBoxing Allow boxing conversions of arguments.
1845 * @param useVarargs Box trailing arguments into an array for varargs.
1846 */
1847 Symbol findMethod(Env<AttrContext> env,
1848 Type site,
1849 Name name,
1850 List<Type> argtypes,
1851 List<Type> typeargtypes,
1852 boolean allowBoxing,
1853 boolean useVarargs) {
1854 Symbol bestSoFar = methodNotFound;
1855 bestSoFar = findMethod(env,
1856 site,
1857 name,
1858 argtypes,
1859 typeargtypes,
1860 site.tsym.type,
1861 bestSoFar,
1862 allowBoxing,
1863 useVarargs);
1864 return bestSoFar;
1865 }
1866 // where
1867 private Symbol findMethod(Env<AttrContext> env,
1868 Type site,
1869 Name name,
1870 List<Type> argtypes,
1871 List<Type> typeargtypes,
1872 Type intype,
1873 Symbol bestSoFar,
1874 boolean allowBoxing,
1875 boolean useVarargs) {
1876 @SuppressWarnings({"unchecked","rawtypes"})
1877 List<Type>[] itypes = (List<Type>[])new List[] { List.<Type>nil(), List.<Type>nil() };
1878
1879 InterfaceLookupPhase iphase = InterfaceLookupPhase.ABSTRACT_OK;
1880 boolean isInterface = site.tsym.isInterface();
1881 for (TypeSymbol s : isInterface ? List.of(intype.tsym) : superclasses(intype)) {
1882 bestSoFar = findMethodInScope(env, site, name, argtypes, typeargtypes,
1883 s.members(), bestSoFar, allowBoxing, useVarargs, true);
1884 if (name == names.init) return bestSoFar;
1885 iphase = (iphase == null) ? null : iphase.update(s, this);
1886 if (iphase != null) {
1887 for (Type itype : types.interfaces(s.type)) {
1888 itypes[iphase.ordinal()] = types.union(types.closure(itype), itypes[iphase.ordinal()]);
1889 }
1890 }
1891 }
1892
1893 Symbol concrete = bestSoFar.kind.isValid() &&
1894 (bestSoFar.flags() & ABSTRACT) == 0 ?
1895 bestSoFar : methodNotFound;
1896
1897 for (InterfaceLookupPhase iphase2 : InterfaceLookupPhase.values()) {
1898 //keep searching for abstract methods
1899 for (Type itype : itypes[iphase2.ordinal()]) {
1900 if (!itype.isInterface()) continue; //skip j.l.Object (included by Types.closure())
1901 if (iphase2 == InterfaceLookupPhase.DEFAULT_OK &&
1902 (itype.tsym.flags() & DEFAULT) == 0) continue;
1903 bestSoFar = findMethodInScope(env, site, name, argtypes, typeargtypes,
1904 itype.tsym.members(), bestSoFar, allowBoxing, useVarargs, true);
1905 if (concrete != bestSoFar &&
1906 concrete.kind.isValid() &&
1907 bestSoFar.kind.isValid() &&
1908 types.isSubSignature(concrete.type, bestSoFar.type)) {
1909 //this is an hack - as javac does not do full membership checks
1910 //most specific ends up comparing abstract methods that might have
1911 //been implemented by some concrete method in a subclass and,
1912 //because of raw override, it is possible for an abstract method
1913 //to be more specific than the concrete method - so we need
1914 //to explicitly call that out (see CR 6178365)
1915 bestSoFar = concrete;
1916 }
1917 }
1918 }
1919 if (isInterface && bestSoFar.kind.isResolutionError()) {
1920 bestSoFar = findMethodInScope(env, site, name, argtypes, typeargtypes,
1921 syms.objectType.tsym.members(), bestSoFar, allowBoxing, useVarargs, true);
1922 if (bestSoFar.kind.isValid()) {
1923 Symbol baseSymbol = bestSoFar;
1924 bestSoFar = new MethodSymbol(bestSoFar.flags_field, bestSoFar.name, bestSoFar.type, intype.tsym) {
1925 @Override
1926 public Symbol baseSymbol() {
1927 return baseSymbol;
1928 }
1929 };
1930 }
1931 }
1932 return bestSoFar;
1933 }
1934
1935 enum InterfaceLookupPhase {
1936 ABSTRACT_OK() {
1937 @Override
1938 InterfaceLookupPhase update(Symbol s, Resolve rs) {
1939 //We should not look for abstract methods if receiver is a concrete class
1940 //(as concrete classes are expected to implement all abstracts coming
1941 //from superinterfaces)
1942 if ((s.flags() & (ABSTRACT | INTERFACE | ENUM)) != 0) {
1943 return this;
1944 } else {
1945 return DEFAULT_OK;
1946 }
1947 }
1948 },
1949 DEFAULT_OK() {
1950 @Override
1951 InterfaceLookupPhase update(Symbol s, Resolve rs) {
1952 return this;
1953 }
1954 };
1955
1956 abstract InterfaceLookupPhase update(Symbol s, Resolve rs);
1957 }
1958
1959 /**
1960 * Return an Iterable object to scan the superclasses of a given type.
1961 * It's crucial that the scan is done lazily, as we don't want to accidentally
1962 * access more supertypes than strictly needed (as this could trigger completion
1963 * errors if some of the not-needed supertypes are missing/ill-formed).
1964 */
1965 Iterable<TypeSymbol> superclasses(final Type intype) {
1966 return () -> new Iterator<TypeSymbol>() {
1967
1968 List<TypeSymbol> seen = List.nil();
1969 TypeSymbol currentSym = symbolFor(intype);
1970 TypeSymbol prevSym = null;
1971
1972 public boolean hasNext() {
1973 if (currentSym == syms.noSymbol) {
1974 currentSym = symbolFor(types.supertype(prevSym.type));
1975 }
1976 return currentSym != null;
1977 }
1978
1979 public TypeSymbol next() {
1980 prevSym = currentSym;
1981 currentSym = syms.noSymbol;
1982 Assert.check(prevSym != null || prevSym != syms.noSymbol);
1983 return prevSym;
1984 }
1985
1986 public void remove() {
1987 throw new UnsupportedOperationException();
1988 }
1989
1990 TypeSymbol symbolFor(Type t) {
1991 if (!t.hasTag(CLASS) &&
1992 !t.hasTag(TYPEVAR)) {
1993 return null;
1994 }
1995 t = types.skipTypeVars(t, false);
1996 if (seen.contains(t.tsym)) {
1997 //degenerate case in which we have a circular
1998 //class hierarchy - because of ill-formed classfiles
1999 return null;
2000 }
2001 seen = seen.prepend(t.tsym);
2002 return t.tsym;
2003 }
2004 };
2005 }
2006
2007 /** Find unqualified method matching given name, type and value arguments.
2008 * @param env The current environment.
2009 * @param name The method's name.
2010 * @param argtypes The method's value arguments.
2011 * @param typeargtypes The method's type arguments.
2012 * @param allowBoxing Allow boxing conversions of arguments.
2013 * @param useVarargs Box trailing arguments into an array for varargs.
2014 */
2015 Symbol findFun(Env<AttrContext> env, Name name,
2016 List<Type> argtypes, List<Type> typeargtypes,
2017 boolean allowBoxing, boolean useVarargs) {
2018 Symbol bestSoFar = methodNotFound;
2019 Env<AttrContext> env1 = env;
2020 boolean staticOnly = false;
2021 while (env1.outer != null) {
2022 if (isStatic(env1)) staticOnly = true;
2023 Assert.check(env1.info.preferredTreeForDiagnostics == null);
2024 env1.info.preferredTreeForDiagnostics = env.tree;
2025 try {
2026 Symbol sym = findMethod(
2027 env1, env1.enclClass.sym.type, name, argtypes, typeargtypes,
2028 allowBoxing, useVarargs);
2029 if (sym.exists()) {
2030 if (sym.kind == MTH &&
2031 sym.owner.kind == TYP &&
2032 (sym.flags() & STATIC) == 0) {
2033 if (staticOnly)
2034 return new StaticError(sym);
2035 if (env1.info.ctorPrologue && env1 == env)
2036 return new RefBeforeCtorCalledError(sym);
2037 }
2038 return sym;
2039 } else {
2040 bestSoFar = bestOf(bestSoFar, sym);
2041 }
2042 } finally {
2043 env1.info.preferredTreeForDiagnostics = null;
2044 }
2045 if ((env1.enclClass.sym.flags() & STATIC) != 0) staticOnly = true;
2046 env1 = env1.outer;
2047 }
2048
2049 Symbol sym = findMethod(env, syms.predefClass.type, name, argtypes,
2050 typeargtypes, allowBoxing, useVarargs);
2051 if (sym.exists())
2052 return sym;
2053
2054 for (Symbol currentSym : env.toplevel.namedImportScope.getSymbolsByName(name)) {
2055 Symbol origin = env.toplevel.namedImportScope.getOrigin(currentSym).owner;
2056 if (currentSym.kind == MTH) {
2057 if (currentSym.owner.type != origin.type)
2058 currentSym = currentSym.clone(origin);
2059 if (!isAccessible(env, origin.type, currentSym))
2060 currentSym = new AccessError(env, origin.type, currentSym);
2061 bestSoFar = selectBest(env, origin.type,
2062 argtypes, typeargtypes,
2063 currentSym, bestSoFar,
2064 allowBoxing, useVarargs);
2065 }
2066 }
2067 if (bestSoFar.exists())
2068 return bestSoFar;
2069
2070 for (Symbol currentSym : env.toplevel.starImportScope.getSymbolsByName(name)) {
2071 Symbol origin = env.toplevel.starImportScope.getOrigin(currentSym).owner;
2072 if (currentSym.kind == MTH) {
2073 if (currentSym.owner.type != origin.type)
2074 currentSym = currentSym.clone(origin);
2075 if (!isAccessible(env, origin.type, currentSym))
2076 currentSym = new AccessError(env, origin.type, currentSym);
2077 bestSoFar = selectBest(env, origin.type,
2078 argtypes, typeargtypes,
2079 currentSym, bestSoFar,
2080 allowBoxing, useVarargs);
2081 }
2082 }
2083 return bestSoFar;
2084 }
2085
2086 /** Load toplevel or member class with given fully qualified name and
2087 * verify that it is accessible.
2088 * @param env The current environment.
2089 * @param name The fully qualified name of the class to be loaded.
2090 */
2091 Symbol loadClass(Env<AttrContext> env, Name name, RecoveryLoadClass recoveryLoadClass) {
2092 try {
2093 ClassSymbol c = finder.loadClass(env.toplevel.modle, name);
2094 return isAccessible(env, c) ? c : new AccessError(env, null, c);
2095 } catch (ClassFinder.BadClassFile err) {
2096 return new BadClassFileError(err);
2097 } catch (CompletionFailure ex) {
2098 Symbol candidate = recoveryLoadClass.loadClass(env, name);
2099
2100 if (candidate != null) {
2101 return candidate;
2102 }
2103
2104 return typeNotFound;
2105 }
2106 }
2107
2108 public interface RecoveryLoadClass {
2109 Symbol loadClass(Env<AttrContext> env, Name name);
2110 }
2111
2112 private final RecoveryLoadClass noRecovery = (env, name) -> null;
2113
2114 private final RecoveryLoadClass doRecoveryLoadClass = new RecoveryLoadClass() {
2115 @Override public Symbol loadClass(Env<AttrContext> env, Name name) {
2116 List<Name> candidates = Convert.classCandidates(name);
2117 return lookupInvisibleSymbol(env, name,
2118 n -> () -> createCompoundIterator(candidates,
2119 c -> syms.getClassesForName(c)
2120 .iterator()),
2121 (ms, n) -> {
2122 for (Name candidate : candidates) {
2123 try {
2124 return finder.loadClass(ms, candidate);
2125 } catch (CompletionFailure cf) {
2126 //ignore
2127 }
2128 }
2129 return null;
2130 }, sym -> sym.kind == Kind.TYP, typeNotFound);
2131 }
2132 };
2133
2134 private final RecoveryLoadClass namedImportScopeRecovery = (env, name) -> {
2135 Scope importScope = env.toplevel.namedImportScope;
2136 Symbol existing = importScope.findFirst(Convert.shortName(name),
2137 sym -> sym.kind == TYP && sym.flatName() == name);
2138
2139 if (existing != null) {
2140 return new InvisibleSymbolError(env, true, existing);
2141 }
2142 return null;
2143 };
2144
2145 private final RecoveryLoadClass starImportScopeRecovery = (env, name) -> {
2146 Scope importScope = env.toplevel.starImportScope;
2147 Symbol existing = importScope.findFirst(Convert.shortName(name),
2148 sym -> sym.kind == TYP && sym.flatName() == name);
2149
2150 if (existing != null) {
2151 try {
2152 existing = finder.loadClass(existing.packge().modle, name);
2153
2154 return new InvisibleSymbolError(env, true, existing);
2155 } catch (CompletionFailure cf) {
2156 //ignore
2157 }
2158 }
2159
2160 return null;
2161 };
2162
2163 Symbol lookupPackage(Env<AttrContext> env, Name name) {
2164 PackageSymbol pack = syms.lookupPackage(env.toplevel.modle, name);
2165
2166 if (allowModules && isImportOnDemand(env, name)) {
2167 if (pack.members().isEmpty()) {
2168 return lookupInvisibleSymbol(env, name, syms::getPackagesForName, syms::enterPackage, sym -> {
2169 sym.complete();
2170 return !sym.members().isEmpty();
2171 }, pack);
2172 }
2173 }
2174
2175 return pack;
2176 }
2177
2178 private boolean isImportOnDemand(Env<AttrContext> env, Name name) {
2179 if (!env.tree.hasTag(IMPORT))
2180 return false;
2181
2182 JCTree qualid = ((JCImport) env.tree).qualid;
2183
2184 if (!qualid.hasTag(SELECT))
2185 return false;
2186
2187 if (TreeInfo.name(qualid) != names.asterisk)
2188 return false;
2189
2190 return TreeInfo.fullName(((JCFieldAccess) qualid).selected) == name;
2191 }
2192
2193 private <S extends Symbol> Symbol lookupInvisibleSymbol(Env<AttrContext> env,
2194 Name name,
2195 Function<Name, Iterable<S>> get,
2196 BiFunction<ModuleSymbol, Name, S> load,
2197 Predicate<S> validate,
2198 Symbol defaultResult) {
2199 //even if a class/package cannot be found in the current module and among packages in modules
2200 //it depends on that are exported for any or this module, the class/package may exist internally
2201 //in some of these modules, or may exist in a module on which this module does not depend.
2202 //Provide better diagnostic in such cases by looking for the class in any module:
2203 Iterable<? extends S> candidates = get.apply(name);
2204
2205 for (S sym : candidates) {
2206 if (validate.test(sym))
2207 return createInvisibleSymbolError(env, sym);
2208 }
2209
2210 Set<ModuleSymbol> recoverableModules = new HashSet<>(syms.getAllModules());
2211
2212 recoverableModules.add(syms.unnamedModule);
2213 recoverableModules.remove(env.toplevel.modle);
2214
2215 for (ModuleSymbol ms : recoverableModules) {
2216 //avoid overly eager completing classes from source-based modules, as those
2217 //may not be completable with the current compiler settings:
2218 if (ms.sourceLocation == null) {
2219 if (ms.classLocation == null) {
2220 ms = moduleFinder.findModule(ms);
2221 }
2222
2223 if (ms.kind != ERR) {
2224 S sym = load.apply(ms, name);
2225
2226 if (sym != null && validate.test(sym)) {
2227 return createInvisibleSymbolError(env, sym);
2228 }
2229 }
2230 }
2231 }
2232
2233 return defaultResult;
2234 }
2235
2236 private Symbol createInvisibleSymbolError(Env<AttrContext> env, Symbol sym) {
2237 if (symbolPackageVisible(env, sym)) {
2238 return new AccessError(env, null, sym);
2239 } else {
2240 return new InvisibleSymbolError(env, false, sym);
2241 }
2242 }
2243
2244 private boolean symbolPackageVisible(Env<AttrContext> env, Symbol sym) {
2245 ModuleSymbol envMod = env.toplevel.modle;
2246 PackageSymbol symPack = sym.packge();
2247 return envMod == symPack.modle ||
2248 envMod.visiblePackages.containsKey(symPack.fullname);
2249 }
2250
2251 /**
2252 * Find a type declared in a scope (not inherited). Return null
2253 * if none is found.
2254 * @param env The current environment.
2255 * @param site The original type from where the selection takes
2256 * place.
2257 * @param name The type's name.
2258 * @param c The class to search for the member type. This is
2259 * always a superclass or implemented interface of
2260 * site's class.
2261 */
2262 Symbol findImmediateMemberType(Env<AttrContext> env,
2263 Type site,
2264 Name name,
2265 TypeSymbol c) {
2266 for (Symbol sym : c.members().getSymbolsByName(name)) {
2267 if (sym.kind == TYP) {
2268 return isAccessible(env, site, sym)
2269 ? sym
2270 : new AccessError(env, site, sym);
2271 }
2272 }
2273 return typeNotFound;
2274 }
2275
2276 /** Find a member type inherited from a superclass or interface.
2277 * @param env The current environment.
2278 * @param site The original type from where the selection takes
2279 * place.
2280 * @param name The type's name.
2281 * @param c The class to search for the member type. This is
2282 * always a superclass or implemented interface of
2283 * site's class.
2284 */
2285 Symbol findInheritedMemberType(Env<AttrContext> env,
2286 Type site,
2287 Name name,
2288 TypeSymbol c) {
2289 Symbol bestSoFar = typeNotFound;
2290 Symbol sym;
2291 Type st = types.supertype(c.type);
2292 if (st != null && st.hasTag(CLASS)) {
2293 sym = findMemberType(env, site, name, st.tsym);
2294 bestSoFar = bestOf(bestSoFar, sym);
2295 }
2296 for (List<Type> l = types.interfaces(c.type);
2297 bestSoFar.kind != AMBIGUOUS && l.nonEmpty();
2298 l = l.tail) {
2299 sym = findMemberType(env, site, name, l.head.tsym);
2300 if (!bestSoFar.kind.isResolutionError() &&
2301 !sym.kind.isResolutionError() &&
2302 sym.owner != bestSoFar.owner)
2303 bestSoFar = new AmbiguityError(bestSoFar, sym);
2304 else
2305 bestSoFar = bestOf(bestSoFar, sym);
2306 }
2307 return bestSoFar;
2308 }
2309
2310 /** Find qualified member type.
2311 * @param env The current environment.
2312 * @param site The original type from where the selection takes
2313 * place.
2314 * @param name The type's name.
2315 * @param c The class to search for the member type. This is
2316 * always a superclass or implemented interface of
2317 * site's class.
2318 */
2319 Symbol findMemberType(Env<AttrContext> env,
2320 Type site,
2321 Name name,
2322 TypeSymbol c) {
2323 Symbol sym = findImmediateMemberType(env, site, name, c);
2324
2325 if (sym != typeNotFound)
2326 return sym;
2327
2328 return findInheritedMemberType(env, site, name, c);
2329
2330 }
2331
2332 /** Find a global type in given scope and load corresponding class.
2333 * @param env The current environment.
2334 * @param scope The scope in which to look for the type.
2335 * @param name The type's name.
2336 */
2337 Symbol findGlobalType(Env<AttrContext> env, Scope scope, Name name, RecoveryLoadClass recoveryLoadClass) {
2338 Symbol bestSoFar = typeNotFound;
2339 for (Symbol s : scope.getSymbolsByName(name)) {
2340 Symbol sym = loadClass(env, s.flatName(), recoveryLoadClass);
2341 if (bestSoFar.kind == TYP && sym.kind == TYP &&
2342 bestSoFar != sym)
2343 return new AmbiguityError(bestSoFar, sym);
2344 else
2345 bestSoFar = bestOf(bestSoFar, sym);
2346 }
2347 return bestSoFar;
2348 }
2349
2350 Symbol findTypeVar(Env<AttrContext> env, Name name, boolean staticOnly) {
2351 for (Symbol sym : env.info.scope.getSymbolsByName(name)) {
2352 if (sym.kind == TYP) {
2353 if (sym.type.hasTag(TYPEVAR) &&
2354 (staticOnly || (isStatic(env) && sym.owner.kind == TYP)))
2355 // if staticOnly is set, it means that we have recursed through a static declaration,
2356 // so type variable symbols should not be accessible. If staticOnly is unset, but
2357 // we are in a static declaration (field or method), we should not allow type-variables
2358 // defined in the enclosing class to "leak" into this context.
2359 return new StaticError(sym);
2360 return sym;
2361 }
2362 }
2363 return typeNotFound;
2364 }
2365
2366 /** Find an unqualified type symbol.
2367 * @param env The current environment.
2368 * @param name The type's name.
2369 */
2370 Symbol findType(Env<AttrContext> env, Name name) {
2371 if (name == names.empty)
2372 return typeNotFound; // do not allow inadvertent "lookup" of anonymous types
2373 Symbol bestSoFar = typeNotFound;
2374 Symbol sym;
2375 boolean staticOnly = false;
2376 for (Env<AttrContext> env1 = env; env1.outer != null; env1 = env1.outer) {
2377 // First, look for a type variable and the first member type
2378 final Symbol tyvar = findTypeVar(env1, name, staticOnly);
2379 if (isStatic(env1)) staticOnly = true;
2380 sym = findImmediateMemberType(env1, env1.enclClass.sym.type,
2381 name, env1.enclClass.sym);
2382
2383 // Return the type variable if we have it, and have no
2384 // immediate member, OR the type variable is for a method.
2385 if (tyvar != typeNotFound) {
2386 if (env.baseClause || sym == typeNotFound ||
2387 (tyvar.kind == TYP && tyvar.exists() &&
2388 tyvar.owner.kind == MTH)) {
2389 return tyvar;
2390 }
2391 }
2392
2393 // If the environment is a class def, finish up,
2394 // otherwise, do the entire findMemberType
2395 if (sym == typeNotFound)
2396 sym = findInheritedMemberType(env1, env1.enclClass.sym.type,
2397 name, env1.enclClass.sym);
2398
2399 if (staticOnly && sym.kind == TYP &&
2400 sym.type.hasTag(CLASS) &&
2401 sym.type.getEnclosingType().hasTag(CLASS) &&
2402 env1.enclClass.sym.type.isParameterized() &&
2403 sym.type.getEnclosingType().isParameterized())
2404 return new StaticError(sym);
2405 else if (sym.exists()) return sym;
2406 else bestSoFar = bestOf(bestSoFar, sym);
2407
2408 JCClassDecl encl = env1.baseClause ? (JCClassDecl)env1.tree : env1.enclClass;
2409 if ((encl.sym.flags() & STATIC) != 0)
2410 staticOnly = true;
2411 }
2412
2413 if (!env.tree.hasTag(IMPORT)) {
2414 sym = findGlobalType(env, env.toplevel.namedImportScope, name, namedImportScopeRecovery);
2415 if (sym.exists()) return sym;
2416 else bestSoFar = bestOf(bestSoFar, sym);
2417
2418 sym = findGlobalType(env, env.toplevel.toplevelScope, name, noRecovery);
2419 if (sym.exists()) return sym;
2420 else bestSoFar = bestOf(bestSoFar, sym);
2421
2422 sym = findGlobalType(env, env.toplevel.packge.members(), name, noRecovery);
2423 if (sym.exists()) return sym;
2424 else bestSoFar = bestOf(bestSoFar, sym);
2425
2426 sym = findGlobalType(env, env.toplevel.starImportScope, name, starImportScopeRecovery);
2427 if (sym.exists()) return sym;
2428 else bestSoFar = bestOf(bestSoFar, sym);
2429 }
2430
2431 return bestSoFar;
2432 }
2433
2434 /** Find an unqualified identifier which matches a specified kind set.
2435 * @param pos position on which report warnings, if any;
2436 * null warnings should not be reported
2437 * @param env The current environment.
2438 * @param name The identifier's name.
2439 * @param kind Indicates the possible symbol kinds
2440 * (a subset of VAL, TYP, PCK).
2441 */
2442 Symbol findIdent(DiagnosticPosition pos, Env<AttrContext> env, Name name, KindSelector kind) {
2443 try {
2444 return checkNonExistentType(checkRestrictedType(pos, findIdentInternal(pos, env, name, kind), name));
2445 } catch (ClassFinder.BadClassFile err) {
2446 return new BadClassFileError(err);
2447 } catch (CompletionFailure cf) {
2448 chk.completionError(pos, cf);
2449 return typeNotFound;
2450 }
2451 }
2452
2453 Symbol findIdentInternal(DiagnosticPosition pos, Env<AttrContext> env, Name name, KindSelector kind) {
2454 Symbol bestSoFar = typeNotFound;
2455 Symbol sym;
2456
2457 if (kind.contains(KindSelector.VAL)) {
2458 sym = findVar(pos, env, name);
2459 if (sym.exists()) return sym;
2460 else bestSoFar = bestOf(bestSoFar, sym);
2461 }
2462
2463 if (kind.contains(KindSelector.TYP)) {
2464 sym = findType(env, name);
2465 if (sym.exists()) return sym;
2466 else bestSoFar = bestOf(bestSoFar, sym);
2467 }
2468
2469 if (kind.contains(KindSelector.PCK))
2470 return lookupPackage(env, name);
2471 else return bestSoFar;
2472 }
2473
2474 /** Find an identifier in a package which matches a specified kind set.
2475 * @param pos position on which report warnings, if any;
2476 * null warnings should not be reported
2477 * @param env The current environment.
2478 * @param name The identifier's name.
2479 * @param kind Indicates the possible symbol kinds
2480 * (a nonempty subset of TYP, PCK).
2481 */
2482 Symbol findIdentInPackage(DiagnosticPosition pos,
2483 Env<AttrContext> env, TypeSymbol pck,
2484 Name name, KindSelector kind) {
2485 return checkNonExistentType(checkRestrictedType(pos, findIdentInPackageInternal(env, pck, name, kind), name));
2486 }
2487
2488 Symbol findIdentInPackageInternal(Env<AttrContext> env, TypeSymbol pck,
2489 Name name, KindSelector kind) {
2490 Name fullname = TypeSymbol.formFullName(name, pck);
2491 Symbol bestSoFar = typeNotFound;
2492 if (kind.contains(KindSelector.TYP)) {
2493 RecoveryLoadClass recoveryLoadClass =
2494 allowModules && !kind.contains(KindSelector.PCK) &&
2495 !pck.exists() && !env.info.attributionMode.isSpeculative ?
2496 doRecoveryLoadClass : noRecovery;
2497 Symbol sym = loadClass(env, fullname, recoveryLoadClass);
2498 if (sym.exists()) {
2499 // don't allow programs to use flatnames
2500 if (name == sym.name) return sym;
2501 }
2502 else bestSoFar = bestOf(bestSoFar, sym);
2503 }
2504 if (kind.contains(KindSelector.PCK)) {
2505 return lookupPackage(env, fullname);
2506 }
2507 return bestSoFar;
2508 }
2509
2510 /** Find an identifier among the members of a given type `site'.
2511 * @param pos position on which report warnings, if any;
2512 * null warnings should not be reported
2513 * @param env The current environment.
2514 * @param site The type containing the symbol to be found.
2515 * @param name The identifier's name.
2516 * @param kind Indicates the possible symbol kinds
2517 * (a subset of VAL, TYP).
2518 */
2519 Symbol findIdentInType(DiagnosticPosition pos,
2520 Env<AttrContext> env, Type site,
2521 Name name, KindSelector kind) {
2522 try {
2523 return checkNonExistentType(checkRestrictedType(pos, findIdentInTypeInternal(env, site, name, kind), name));
2524 } catch (ClassFinder.BadClassFile err) {
2525 return new BadClassFileError(err);
2526 } catch (CompletionFailure cf) {
2527 chk.completionError(pos, cf);
2528 return typeNotFound;
2529 }
2530 }
2531
2532 private Symbol checkNonExistentType(Symbol symbol) {
2533 /* Guard against returning a type is not on the class path of the current compilation,
2534 * but *was* on the class path of a separate compilation that produced a class file
2535 * that is on the class path of the current compilation. Such a type will fail completion
2536 * but the completion failure may have been silently swallowed (e.g. missing annotation types)
2537 * with an error stub symbol lingering in the symbol tables.
2538 */
2539 return symbol instanceof ClassSymbol c && c.type.isErroneous() && c.classfile == null ? typeNotFound : symbol;
2540 }
2541
2542 Symbol findIdentInTypeInternal(Env<AttrContext> env, Type site,
2543 Name name, KindSelector kind) {
2544 Symbol bestSoFar = typeNotFound;
2545 Symbol sym;
2546 if (kind.contains(KindSelector.VAL)) {
2547 sym = findField(env, site, name, site.tsym);
2548 if (sym.exists()) return sym;
2549 else bestSoFar = bestOf(bestSoFar, sym);
2550 }
2551
2552 if (kind.contains(KindSelector.TYP)) {
2553 sym = findMemberType(env, site, name, site.tsym);
2554 if (sym.exists()) return sym;
2555 else bestSoFar = bestOf(bestSoFar, sym);
2556 }
2557 return bestSoFar;
2558 }
2559
2560 private Symbol checkRestrictedType(DiagnosticPosition pos, Symbol bestSoFar, Name name) {
2561 if (bestSoFar.kind == TYP || bestSoFar.kind == ABSENT_TYP) {
2562 if (allowLocalVariableTypeInference && name.equals(names.var)) {
2563 bestSoFar = new BadRestrictedTypeError(names.var);
2564 } else if (name.equals(names.yield)) {
2565 if (allowYieldStatement) {
2566 bestSoFar = new BadRestrictedTypeError(names.yield);
2567 } else if (pos != null) {
2568 log.warning(pos, Warnings.IllegalRefToRestrictedType(names.yield));
2569 }
2570 }
2571 }
2572 return bestSoFar;
2573 }
2574
2575 /* ***************************************************************************
2576 * Access checking
2577 * The following methods convert ResolveErrors to ErrorSymbols, issuing
2578 * an error message in the process
2579 ****************************************************************************/
2580
2581 /** If `sym' is a bad symbol: report error and return errSymbol
2582 * else pass through unchanged,
2583 * additional arguments duplicate what has been used in trying to find the
2584 * symbol {@literal (--> flyweight pattern)}. This improves performance since we
2585 * expect misses to happen frequently.
2586 *
2587 * @param sym The symbol that was found, or a ResolveError.
2588 * @param pos The position to use for error reporting.
2589 * @param location The symbol the served as a context for this lookup
2590 * @param site The original type from where the selection took place.
2591 * @param name The symbol's name.
2592 * @param qualified Did we get here through a qualified expression resolution?
2593 * @param argtypes The invocation's value arguments,
2594 * if we looked for a method.
2595 * @param typeargtypes The invocation's type arguments,
2596 * if we looked for a method.
2597 * @param logResolveHelper helper class used to log resolve errors
2598 */
2599 Symbol accessInternal(Symbol sym,
2600 DiagnosticPosition pos,
2601 Symbol location,
2602 Type site,
2603 Name name,
2604 boolean qualified,
2605 List<Type> argtypes,
2606 List<Type> typeargtypes,
2607 LogResolveHelper logResolveHelper) {
2608 if (sym.kind.isResolutionError()) {
2609 ResolveError errSym = (ResolveError)sym.baseSymbol();
2610 sym = errSym.access(name, qualified ? site.tsym : syms.noSymbol);
2611 argtypes = logResolveHelper.getArgumentTypes(errSym, sym, name, argtypes);
2612 if (logResolveHelper.resolveDiagnosticNeeded(site, argtypes, typeargtypes)) {
2613 logResolveError(errSym, pos, location, site, name, argtypes, typeargtypes);
2614 }
2615 }
2616 return sym;
2617 }
2618
2619 /**
2620 * Variant of the generalized access routine, to be used for generating method
2621 * resolution diagnostics
2622 */
2623 Symbol accessMethod(Symbol sym,
2624 DiagnosticPosition pos,
2625 Symbol location,
2626 Type site,
2627 Name name,
2628 boolean qualified,
2629 List<Type> argtypes,
2630 List<Type> typeargtypes) {
2631 return accessInternal(sym, pos, location, site, name, qualified, argtypes, typeargtypes, methodLogResolveHelper);
2632 }
2633
2634 /** Same as original accessMethod(), but without location.
2635 */
2636 Symbol accessMethod(Symbol sym,
2637 DiagnosticPosition pos,
2638 Type site,
2639 Name name,
2640 boolean qualified,
2641 List<Type> argtypes,
2642 List<Type> typeargtypes) {
2643 return accessMethod(sym, pos, site.tsym, site, name, qualified, argtypes, typeargtypes);
2644 }
2645
2646 /**
2647 * Variant of the generalized access routine, to be used for generating variable,
2648 * type resolution diagnostics
2649 */
2650 Symbol accessBase(Symbol sym,
2651 DiagnosticPosition pos,
2652 Symbol location,
2653 Type site,
2654 Name name,
2655 boolean qualified) {
2656 return accessInternal(sym, pos, location, site, name, qualified, List.nil(), null, basicLogResolveHelper);
2657 }
2658
2659 /** Same as original accessBase(), but without location.
2660 */
2661 Symbol accessBase(Symbol sym,
2662 DiagnosticPosition pos,
2663 Type site,
2664 Name name,
2665 boolean qualified) {
2666 return accessBase(sym, pos, site.tsym, site, name, qualified);
2667 }
2668
2669 interface LogResolveHelper {
2670 boolean resolveDiagnosticNeeded(Type site, List<Type> argtypes, List<Type> typeargtypes);
2671 List<Type> getArgumentTypes(ResolveError errSym, Symbol accessedSym, Name name, List<Type> argtypes);
2672 }
2673
2674 LogResolveHelper basicLogResolveHelper = new LogResolveHelper() {
2675 public boolean resolveDiagnosticNeeded(Type site, List<Type> argtypes, List<Type> typeargtypes) {
2676 return !site.isErroneous();
2677 }
2678 public List<Type> getArgumentTypes(ResolveError errSym, Symbol accessedSym, Name name, List<Type> argtypes) {
2679 return argtypes;
2680 }
2681 };
2682
2683 LogResolveHelper silentLogResolveHelper = new LogResolveHelper() {
2684 public boolean resolveDiagnosticNeeded(Type site, List<Type> argtypes, List<Type> typeargtypes) {
2685 return false;
2686 }
2687 public List<Type> getArgumentTypes(ResolveError errSym, Symbol accessedSym, Name name, List<Type> argtypes) {
2688 return argtypes;
2689 }
2690 };
2691
2692 LogResolveHelper methodLogResolveHelper = new LogResolveHelper() {
2693 public boolean resolveDiagnosticNeeded(Type site, List<Type> argtypes, List<Type> typeargtypes) {
2694 return !site.isErroneous() &&
2695 !Type.isErroneous(argtypes) &&
2696 (typeargtypes == null || !Type.isErroneous(typeargtypes));
2697 }
2698 public List<Type> getArgumentTypes(ResolveError errSym, Symbol accessedSym, Name name, List<Type> argtypes) {
2699 return argtypes.map(new ResolveDeferredRecoveryMap(AttrMode.SPECULATIVE, accessedSym, currentResolutionContext.step));
2700 }
2701 };
2702
2703 class ResolveDeferredRecoveryMap extends DeferredAttr.RecoveryDeferredTypeMap {
2704
2705 public ResolveDeferredRecoveryMap(AttrMode mode, Symbol msym, MethodResolutionPhase step) {
2706 deferredAttr.super(mode, msym, step);
2707 }
2708
2709 @Override
2710 protected Type typeOf(DeferredType dt, Type pt) {
2711 Type res = super.typeOf(dt, pt);
2712 if (!res.isErroneous()) {
2713 switch (TreeInfo.skipParens(dt.tree).getTag()) {
2714 case LAMBDA:
2715 case REFERENCE:
2716 return dt;
2717 case CONDEXPR:
2718 return res == Type.recoveryType ?
2719 dt : res;
2720 }
2721 }
2722 return res;
2723 }
2724 }
2725
2726 /** Check that sym is not an abstract method.
2727 */
2728 void checkNonAbstract(DiagnosticPosition pos, Symbol sym) {
2729 if ((sym.flags() & ABSTRACT) != 0 && (sym.flags() & DEFAULT) == 0)
2730 log.error(pos,
2731 Errors.AbstractCantBeAccessedDirectly(kindName(sym),sym, sym.location()));
2732 }
2733
2734 /* ***************************************************************************
2735 * Name resolution
2736 * Naming conventions are as for symbol lookup
2737 * Unlike the find... methods these methods will report access errors
2738 ****************************************************************************/
2739
2740 /** Resolve an unqualified (non-method) identifier.
2741 * @param pos The position to use for error reporting.
2742 * @param env The environment current at the identifier use.
2743 * @param name The identifier's name.
2744 * @param kind The set of admissible symbol kinds for the identifier.
2745 */
2746 Symbol resolveIdent(DiagnosticPosition pos, Env<AttrContext> env,
2747 Name name, KindSelector kind) {
2748 return accessBase(
2749 findIdent(pos, env, name, kind),
2750 pos, env.enclClass.sym.type, name, false);
2751 }
2752
2753 /** Resolve an unqualified method identifier.
2754 * @param pos The position to use for error reporting.
2755 * @param env The environment current at the method invocation.
2756 * @param name The identifier's name.
2757 * @param argtypes The types of the invocation's value arguments.
2758 * @param typeargtypes The types of the invocation's type arguments.
2759 */
2760 Symbol resolveMethod(DiagnosticPosition pos,
2761 Env<AttrContext> env,
2762 Name name,
2763 List<Type> argtypes,
2764 List<Type> typeargtypes) {
2765 return lookupMethod(env, pos, env.enclClass.sym, resolveMethodCheck,
2766 new BasicLookupHelper(name, env.enclClass.sym.type, argtypes, typeargtypes) {
2767 @Override
2768 Symbol doLookup(Env<AttrContext> env, MethodResolutionPhase phase) {
2769 return findFun(env, name, argtypes, typeargtypes,
2770 phase.isBoxingRequired(),
2771 phase.isVarargsRequired());
2772 }});
2773 }
2774
2775 /** Resolve a qualified method identifier
2776 * @param pos The position to use for error reporting.
2777 * @param env The environment current at the method invocation.
2778 * @param site The type of the qualifying expression, in which
2779 * identifier is searched.
2780 * @param name The identifier's name.
2781 * @param argtypes The types of the invocation's value arguments.
2782 * @param typeargtypes The types of the invocation's type arguments.
2783 */
2784 Symbol resolveQualifiedMethod(DiagnosticPosition pos, Env<AttrContext> env,
2785 Type site, Name name, List<Type> argtypes,
2786 List<Type> typeargtypes) {
2787 return resolveQualifiedMethod(pos, env, site.tsym, site, name, argtypes, typeargtypes);
2788 }
2789 Symbol resolveQualifiedMethod(DiagnosticPosition pos, Env<AttrContext> env,
2790 Symbol location, Type site, Name name, List<Type> argtypes,
2791 List<Type> typeargtypes) {
2792 return resolveQualifiedMethod(new MethodResolutionContext(), pos, env, location, site, name, argtypes, typeargtypes);
2793 }
2794 private Symbol resolveQualifiedMethod(MethodResolutionContext resolveContext,
2795 DiagnosticPosition pos, Env<AttrContext> env,
2796 Symbol location, Type site, Name name, List<Type> argtypes,
2797 List<Type> typeargtypes) {
2798 return lookupMethod(env, pos, location, resolveContext, new BasicLookupHelper(name, site, argtypes, typeargtypes) {
2799 @Override
2800 Symbol doLookup(Env<AttrContext> env, MethodResolutionPhase phase) {
2801 return findMethod(env, site, name, argtypes, typeargtypes,
2802 phase.isBoxingRequired(),
2803 phase.isVarargsRequired());
2804 }
2805 @Override
2806 Symbol access(Env<AttrContext> env, DiagnosticPosition pos, Symbol location, Symbol sym) {
2807 if (sym.kind.isResolutionError()) {
2808 sym = super.access(env, pos, location, sym);
2809 } else {
2810 MethodSymbol msym = (MethodSymbol)sym;
2811 if ((msym.flags() & SIGNATURE_POLYMORPHIC) != 0) {
2812 env.info.pendingResolutionPhase = BASIC;
2813 return findPolymorphicSignatureInstance(env, sym, argtypes);
2814 }
2815 }
2816 return sym;
2817 }
2818 });
2819 }
2820
2821 /** Find or create an implicit method of exactly the given type (after erasure).
2822 * Searches in a side table, not the main scope of the site.
2823 * This emulates the lookup process required by JSR 292 in JVM.
2824 * @param env Attribution environment
2825 * @param spMethod signature polymorphic method - i.e. MH.invokeExact
2826 * @param argtypes The required argument types
2827 */
2828 Symbol findPolymorphicSignatureInstance(Env<AttrContext> env,
2829 final Symbol spMethod,
2830 List<Type> argtypes) {
2831 Type mtype = infer.instantiatePolymorphicSignatureInstance(env,
2832 (MethodSymbol)spMethod, currentResolutionContext, argtypes);
2833 return findPolymorphicSignatureInstance(spMethod, mtype);
2834 }
2835
2836 Symbol findPolymorphicSignatureInstance(final Symbol spMethod,
2837 Type mtype) {
2838 for (Symbol sym : polymorphicSignatureScope.getSymbolsByName(spMethod.name)) {
2839 // Check that there is already a method symbol for the method
2840 // type and owner
2841 if (types.isSameType(mtype, sym.type) &&
2842 spMethod.owner == sym.owner) {
2843 return sym;
2844 }
2845 }
2846
2847 Type spReturnType = spMethod.asType().getReturnType();
2848 if (types.isSameType(spReturnType, syms.objectType)) {
2849 // Polymorphic return, pass through mtype
2850 } else if (!types.isSameType(spReturnType, mtype.getReturnType())) {
2851 // Retain the sig poly method's return type, which differs from that of mtype
2852 // Will result in an incompatible return type error
2853 mtype = new MethodType(mtype.getParameterTypes(),
2854 spReturnType,
2855 mtype.getThrownTypes(),
2856 syms.methodClass);
2857 }
2858
2859 // Create the desired method
2860 // Retain static modifier is to support invocations to
2861 // MethodHandle.linkTo* methods
2862 long flags = ABSTRACT | HYPOTHETICAL |
2863 spMethod.flags() & (Flags.AccessFlags | Flags.STATIC);
2864 Symbol msym = new MethodSymbol(flags, spMethod.name, mtype, spMethod.owner) {
2865 @Override
2866 public Symbol baseSymbol() {
2867 return spMethod;
2868 }
2869 };
2870 if (!mtype.isErroneous()) { // Cache only if kosher.
2871 polymorphicSignatureScope.enter(msym);
2872 }
2873 return msym;
2874 }
2875
2876 /** Resolve a qualified method identifier, throw a fatal error if not
2877 * found.
2878 * @param pos The position to use for error reporting.
2879 * @param env The environment current at the method invocation.
2880 * @param site The type of the qualifying expression, in which
2881 * identifier is searched.
2882 * @param name The identifier's name.
2883 * @param argtypes The types of the invocation's value arguments.
2884 * @param typeargtypes The types of the invocation's type arguments.
2885 */
2886 public MethodSymbol resolveInternalMethod(DiagnosticPosition pos, Env<AttrContext> env,
2887 Type site, Name name,
2888 List<Type> argtypes,
2889 List<Type> typeargtypes) {
2890 MethodResolutionContext resolveContext = new MethodResolutionContext();
2891 resolveContext.internalResolution = true;
2892 Symbol sym = resolveQualifiedMethod(resolveContext, pos, env, site.tsym,
2893 site, name, argtypes, typeargtypes);
2894 if (sym.kind == MTH) return (MethodSymbol)sym;
2895 else throw new FatalError(
2896 diags.fragment(Fragments.FatalErrCantLocateMeth(name)));
2897 }
2898
2899 /** Resolve constructor.
2900 * @param pos The position to use for error reporting.
2901 * @param env The environment current at the constructor invocation.
2902 * @param site The type of class for which a constructor is searched.
2903 * @param argtypes The types of the constructor invocation's value
2904 * arguments.
2905 * @param typeargtypes The types of the constructor invocation's type
2906 * arguments.
2907 */
2908 Symbol resolveConstructor(DiagnosticPosition pos,
2909 Env<AttrContext> env,
2910 Type site,
2911 List<Type> argtypes,
2912 List<Type> typeargtypes) {
2913 return resolveConstructor(new MethodResolutionContext(), pos, env, site, argtypes, typeargtypes);
2914 }
2915
2916 private Symbol resolveConstructor(MethodResolutionContext resolveContext,
2917 final DiagnosticPosition pos,
2918 Env<AttrContext> env,
2919 Type site,
2920 List<Type> argtypes,
2921 List<Type> typeargtypes) {
2922 return lookupMethod(env, pos, site.tsym, resolveContext, new BasicLookupHelper(names.init, site, argtypes, typeargtypes) {
2923 @Override
2924 Symbol doLookup(Env<AttrContext> env, MethodResolutionPhase phase) {
2925 return findConstructor(pos, env, site, argtypes, typeargtypes,
2926 phase.isBoxingRequired(),
2927 phase.isVarargsRequired());
2928 }
2929 });
2930 }
2931
2932 /** Resolve a constructor, throw a fatal error if not found.
2933 * @param pos The position to use for error reporting.
2934 * @param env The environment current at the method invocation.
2935 * @param site The type to be constructed.
2936 * @param argtypes The types of the invocation's value arguments.
2937 * @param typeargtypes The types of the invocation's type arguments.
2938 */
2939 public MethodSymbol resolveInternalConstructor(DiagnosticPosition pos, Env<AttrContext> env,
2940 Type site,
2941 List<Type> argtypes,
2942 List<Type> typeargtypes) {
2943 MethodResolutionContext resolveContext = new MethodResolutionContext();
2944 resolveContext.internalResolution = true;
2945 Symbol sym = resolveConstructor(resolveContext, pos, env, site, argtypes, typeargtypes);
2946 if (sym.kind == MTH) return (MethodSymbol)sym;
2947 else throw new FatalError(
2948 diags.fragment(Fragments.FatalErrCantLocateCtor(site)));
2949 }
2950
2951 Symbol findConstructor(DiagnosticPosition pos, Env<AttrContext> env,
2952 Type site, List<Type> argtypes,
2953 List<Type> typeargtypes,
2954 boolean allowBoxing,
2955 boolean useVarargs) {
2956 Symbol sym = findMethod(env, site,
2957 names.init, argtypes,
2958 typeargtypes, allowBoxing,
2959 useVarargs);
2960 chk.checkDeprecated(pos, env.info.scope.owner, sym);
2961 chk.checkPreview(pos, env.info.scope.owner, sym);
2962 return sym;
2963 }
2964
2965 /** Resolve constructor using diamond inference.
2966 * @param pos The position to use for error reporting.
2967 * @param env The environment current at the constructor invocation.
2968 * @param site The type of class for which a constructor is searched.
2969 * The scope of this class has been touched in attribution.
2970 * @param argtypes The types of the constructor invocation's value
2971 * arguments.
2972 * @param typeargtypes The types of the constructor invocation's type
2973 * arguments.
2974 */
2975 Symbol resolveDiamond(DiagnosticPosition pos,
2976 Env<AttrContext> env,
2977 Type site,
2978 List<Type> argtypes,
2979 List<Type> typeargtypes) {
2980 return lookupMethod(env, pos, site.tsym, resolveMethodCheck,
2981 new BasicLookupHelper(names.init, site, argtypes, typeargtypes) {
2982 @Override
2983 Symbol doLookup(Env<AttrContext> env, MethodResolutionPhase phase) {
2984 return findDiamond(pos, env, site, argtypes, typeargtypes,
2985 phase.isBoxingRequired(),
2986 phase.isVarargsRequired());
2987 }
2988 @Override
2989 Symbol access(Env<AttrContext> env, DiagnosticPosition pos, Symbol location, Symbol sym) {
2990 if (sym.kind.isResolutionError()) {
2991 if (sym.kind != WRONG_MTH &&
2992 sym.kind != WRONG_MTHS) {
2993 sym = super.access(env, pos, location, sym);
2994 } else {
2995 sym = new DiamondError(sym, currentResolutionContext);
2996 sym = accessMethod(sym, pos, site, names.init, true, argtypes, typeargtypes);
2997 env.info.pendingResolutionPhase = currentResolutionContext.step;
2998 }
2999 }
3000 return sym;
3001 }});
3002 }
3003
3004 /** Find the constructor using diamond inference and do some checks(deprecated and preview).
3005 * @param pos The position to use for error reporting.
3006 * @param env The environment current at the constructor invocation.
3007 * @param site The type of class for which a constructor is searched.
3008 * The scope of this class has been touched in attribution.
3009 * @param argtypes The types of the constructor invocation's value arguments.
3010 * @param typeargtypes The types of the constructor invocation's type arguments.
3011 * @param allowBoxing Allow boxing conversions of arguments.
3012 * @param useVarargs Box trailing arguments into an array for varargs.
3013 */
3014 private Symbol findDiamond(DiagnosticPosition pos,
3015 Env<AttrContext> env,
3016 Type site,
3017 List<Type> argtypes,
3018 List<Type> typeargtypes,
3019 boolean allowBoxing,
3020 boolean useVarargs) {
3021 Symbol sym = findDiamond(env, site, argtypes, typeargtypes, allowBoxing, useVarargs);
3022 chk.checkDeprecated(pos, env.info.scope.owner, sym);
3023 chk.checkPreview(pos, env.info.scope.owner, sym);
3024 return sym;
3025 }
3026
3027 /** This method scans all the constructor symbol in a given class scope -
3028 * assuming that the original scope contains a constructor of the kind:
3029 * {@code Foo(X x, Y y)}, where X,Y are class type-variables declared in Foo,
3030 * a method check is executed against the modified constructor type:
3031 * {@code <X,Y>Foo<X,Y>(X x, Y y)}. This is crucial in order to enable diamond
3032 * inference. The inferred return type of the synthetic constructor IS
3033 * the inferred type for the diamond operator.
3034 */
3035 private Symbol findDiamond(Env<AttrContext> env,
3036 Type site,
3037 List<Type> argtypes,
3038 List<Type> typeargtypes,
3039 boolean allowBoxing,
3040 boolean useVarargs) {
3041 Symbol bestSoFar = methodNotFound;
3042 TypeSymbol tsym = site.tsym.isInterface() ? syms.objectType.tsym : site.tsym;
3043 for (final Symbol sym : tsym.members().getSymbolsByName(names.init)) {
3044 //- System.out.println(" e " + e.sym);
3045 if (sym.kind == MTH &&
3046 (sym.flags_field & SYNTHETIC) == 0) {
3047 List<Type> oldParams = sym.type.hasTag(FORALL) ?
3048 ((ForAll)sym.type).tvars :
3049 List.nil();
3050 Type constrType = new ForAll(site.tsym.type.getTypeArguments().appendList(oldParams),
3051 types.createMethodTypeWithReturn(sym.type.asMethodType(), site));
3052 MethodSymbol newConstr = new MethodSymbol(sym.flags(), names.init, constrType, site.tsym) {
3053 @Override
3054 public Symbol baseSymbol() {
3055 return sym;
3056 }
3057 };
3058 bestSoFar = selectBest(env, site, argtypes, typeargtypes,
3059 newConstr,
3060 bestSoFar,
3061 allowBoxing,
3062 useVarargs);
3063 }
3064 }
3065 return bestSoFar;
3066 }
3067
3068 Symbol getMemberReference(DiagnosticPosition pos,
3069 Env<AttrContext> env,
3070 JCMemberReference referenceTree,
3071 Type site,
3072 Name name) {
3073
3074 site = types.capture(site);
3075
3076 ReferenceLookupHelper lookupHelper = makeReferenceLookupHelper(
3077 referenceTree, site, name, List.nil(), null, VARARITY);
3078
3079 Env<AttrContext> newEnv = env.dup(env.tree, env.info.dup());
3080 Symbol sym = lookupMethod(newEnv, env.tree.pos(), site.tsym,
3081 nilMethodCheck, lookupHelper);
3082
3083 env.info.pendingResolutionPhase = newEnv.info.pendingResolutionPhase;
3084
3085 return sym;
3086 }
3087
3088 ReferenceLookupHelper makeReferenceLookupHelper(JCMemberReference referenceTree,
3089 Type site,
3090 Name name,
3091 List<Type> argtypes,
3092 List<Type> typeargtypes,
3093 MethodResolutionPhase maxPhase) {
3094 if (!name.equals(names.init)) {
3095 //method reference
3096 return new MethodReferenceLookupHelper(referenceTree, name, site, argtypes, typeargtypes, maxPhase);
3097 } else if (site.hasTag(ARRAY)) {
3098 //array constructor reference
3099 return new ArrayConstructorReferenceLookupHelper(referenceTree, site, argtypes, typeargtypes, maxPhase);
3100 } else {
3101 //class constructor reference
3102 return new ConstructorReferenceLookupHelper(referenceTree, site, argtypes, typeargtypes, maxPhase);
3103 }
3104 }
3105
3106 /**
3107 * Resolution of member references is typically done as a single
3108 * overload resolution step, where the argument types A are inferred from
3109 * the target functional descriptor.
3110 *
3111 * If the member reference is a method reference with a type qualifier,
3112 * a two-step lookup process is performed. The first step uses the
3113 * expected argument list A, while the second step discards the first
3114 * type from A (which is treated as a receiver type).
3115 *
3116 * There are two cases in which inference is performed: (i) if the member
3117 * reference is a constructor reference and the qualifier type is raw - in
3118 * which case diamond inference is used to infer a parameterization for the
3119 * type qualifier; (ii) if the member reference is an unbound reference
3120 * where the type qualifier is raw - in that case, during the unbound lookup
3121 * the receiver argument type is used to infer an instantiation for the raw
3122 * qualifier type.
3123 *
3124 * When a multi-step resolution process is exploited, the process of picking
3125 * the resulting symbol is delegated to an helper class {@link com.sun.tools.javac.comp.Resolve.ReferenceChooser}.
3126 *
3127 * This routine returns a pair (T,S), where S is the member reference symbol,
3128 * and T is the type of the class in which S is defined. This is necessary as
3129 * the type T might be dynamically inferred (i.e. if constructor reference
3130 * has a raw qualifier).
3131 */
3132 Pair<Symbol, ReferenceLookupHelper> resolveMemberReference(Env<AttrContext> env,
3133 JCMemberReference referenceTree,
3134 Type site,
3135 Name name,
3136 List<Type> argtypes,
3137 List<Type> typeargtypes,
3138 Type descriptor,
3139 MethodCheck methodCheck,
3140 InferenceContext inferenceContext,
3141 ReferenceChooser referenceChooser) {
3142
3143 //step 1 - bound lookup
3144 ReferenceLookupHelper boundLookupHelper = makeReferenceLookupHelper(
3145 referenceTree, site, name, argtypes, typeargtypes, VARARITY);
3146 Env<AttrContext> boundEnv = env.dup(env.tree, env.info.dup());
3147 MethodResolutionContext boundSearchResolveContext = new MethodResolutionContext();
3148 boundSearchResolveContext.methodCheck = methodCheck;
3149 Symbol boundSym = lookupMethod(boundEnv, env.tree.pos(),
3150 site.tsym, boundSearchResolveContext, boundLookupHelper);
3151 boolean isStaticSelector = TreeInfo.isStaticSelector(referenceTree.expr, names);
3152 ReferenceLookupResult boundRes = new ReferenceLookupResult(boundSym, boundSearchResolveContext, isStaticSelector);
3153 if (dumpMethodReferenceSearchResults) {
3154 dumpMethodReferenceSearchResults(referenceTree, boundSearchResolveContext, boundSym, true);
3155 }
3156
3157 //step 2 - unbound lookup
3158 Symbol unboundSym = methodNotFound;
3159 Env<AttrContext> unboundEnv = env.dup(env.tree, env.info.dup());
3160 ReferenceLookupHelper unboundLookupHelper = boundLookupHelper.unboundLookup(inferenceContext);
3161 ReferenceLookupResult unboundRes = referenceNotFound;
3162 if (unboundLookupHelper != null) {
3163 MethodResolutionContext unboundSearchResolveContext =
3164 new MethodResolutionContext();
3165 unboundSearchResolveContext.methodCheck = methodCheck;
3166 unboundSym = lookupMethod(unboundEnv, env.tree.pos(),
3167 site.tsym, unboundSearchResolveContext, unboundLookupHelper);
3168 unboundRes = new ReferenceLookupResult(unboundSym, unboundSearchResolveContext, isStaticSelector);
3169 if (dumpMethodReferenceSearchResults) {
3170 dumpMethodReferenceSearchResults(referenceTree, unboundSearchResolveContext, unboundSym, false);
3171 }
3172 }
3173
3174 //merge results
3175 Pair<Symbol, ReferenceLookupHelper> res;
3176 ReferenceLookupResult bestRes = referenceChooser.result(boundRes, unboundRes);
3177 res = new Pair<>(bestRes.sym,
3178 bestRes == unboundRes ? unboundLookupHelper : boundLookupHelper);
3179 env.info.pendingResolutionPhase = bestRes == unboundRes ?
3180 unboundEnv.info.pendingResolutionPhase :
3181 boundEnv.info.pendingResolutionPhase;
3182
3183 if (!res.fst.kind.isResolutionError()) {
3184 //handle sigpoly method references
3185 MethodSymbol msym = (MethodSymbol)res.fst;
3186 if ((msym.flags() & SIGNATURE_POLYMORPHIC) != 0) {
3187 env.info.pendingResolutionPhase = BASIC;
3188 res = new Pair<>(findPolymorphicSignatureInstance(msym, descriptor), res.snd);
3189 }
3190 }
3191
3192 return res;
3193 }
3194
3195 private void dumpMethodReferenceSearchResults(JCMemberReference referenceTree,
3196 MethodResolutionContext resolutionContext,
3197 Symbol bestSoFar,
3198 boolean bound) {
3199 ListBuffer<JCDiagnostic> subDiags = new ListBuffer<>();
3200 int pos = 0;
3201 int mostSpecificPos = -1;
3202 for (Candidate c : resolutionContext.candidates) {
3203 if (resolutionContext.step != c.step || !c.isApplicable()) {
3204 continue;
3205 } else {
3206 JCDiagnostic subDiag = null;
3207 if (c.sym.type.hasTag(FORALL)) {
3208 subDiag = diags.fragment(Fragments.PartialInstSig(c.mtype));
3209 }
3210
3211 String key = subDiag == null ?
3212 "applicable.method.found.2" :
3213 "applicable.method.found.3";
3214 subDiags.append(diags.fragment(key, pos,
3215 c.sym.isStatic() ? Fragments.Static : Fragments.NonStatic, c.sym, subDiag));
3216 if (c.sym == bestSoFar)
3217 mostSpecificPos = pos;
3218 pos++;
3219 }
3220 }
3221 JCDiagnostic main = diags.note(
3222 log.currentSource(),
3223 referenceTree,
3224 "method.ref.search.results.multi",
3225 bound ? Fragments.Bound : Fragments.Unbound,
3226 referenceTree.toString(), mostSpecificPos);
3227 JCDiagnostic d = new JCDiagnostic.MultilineDiagnostic(main, subDiags.toList());
3228 log.report(d);
3229 }
3230
3231 /**
3232 * This class is used to represent a method reference lookup result. It keeps track of two
3233 * things: (i) the symbol found during a method reference lookup and (ii) the static kind
3234 * of the lookup (see {@link com.sun.tools.javac.comp.Resolve.ReferenceLookupResult.StaticKind}).
3235 */
3236 static class ReferenceLookupResult {
3237
3238 /**
3239 * Static kind associated with a method reference lookup. Erroneous lookups end up with
3240 * the UNDEFINED kind; successful lookups will end up with either STATIC, NON_STATIC,
3241 * depending on whether all applicable candidates are static or non-static methods,
3242 * respectively. If a successful lookup has both static and non-static applicable methods,
3243 * its kind is set to BOTH.
3244 */
3245 enum StaticKind {
3246 STATIC,
3247 NON_STATIC,
3248 BOTH,
3249 UNDEFINED;
3250
3251 /**
3252 * Retrieve the static kind associated with a given (method) symbol.
3253 */
3254 static StaticKind from(Symbol s) {
3255 return s.isStatic() ?
3256 STATIC : NON_STATIC;
3257 }
3258
3259 /**
3260 * Merge two static kinds together.
3261 */
3262 static StaticKind reduce(StaticKind sk1, StaticKind sk2) {
3263 if (sk1 == UNDEFINED) {
3264 return sk2;
3265 } else if (sk2 == UNDEFINED) {
3266 return sk1;
3267 } else {
3268 return sk1 == sk2 ? sk1 : BOTH;
3269 }
3270 }
3271 }
3272
3273 /** The static kind. */
3274 StaticKind staticKind;
3275
3276 /** The lookup result. */
3277 Symbol sym;
3278
3279 ReferenceLookupResult(Symbol sym, MethodResolutionContext resolutionContext, boolean isStaticSelector) {
3280 this(sym, staticKind(sym, resolutionContext, isStaticSelector));
3281 }
3282
3283 private ReferenceLookupResult(Symbol sym, StaticKind staticKind) {
3284 this.staticKind = staticKind;
3285 this.sym = sym;
3286 }
3287
3288 private static StaticKind staticKind(Symbol sym, MethodResolutionContext resolutionContext, boolean isStaticSelector) {
3289 if (sym.kind == MTH && !isStaticSelector) {
3290 return StaticKind.from(sym);
3291 } else if (sym.kind == MTH || sym.kind == AMBIGUOUS) {
3292 return resolutionContext.candidates.stream()
3293 .filter(c -> c.isApplicable() && c.step == resolutionContext.step)
3294 .map(c -> StaticKind.from(c.sym))
3295 .reduce(StaticKind::reduce)
3296 .orElse(StaticKind.UNDEFINED);
3297 } else {
3298 return StaticKind.UNDEFINED;
3299 }
3300 }
3301
3302 /**
3303 * Does this result corresponds to a successful lookup (i.e. one where a method has been found?)
3304 */
3305 boolean isSuccess() {
3306 return staticKind != StaticKind.UNDEFINED;
3307 }
3308
3309 /**
3310 * Does this result have given static kind?
3311 */
3312 boolean hasKind(StaticKind sk) {
3313 return this.staticKind == sk;
3314 }
3315
3316 /**
3317 * Error recovery helper: can this lookup result be ignored (for the purpose of returning
3318 * some 'better' result) ?
3319 */
3320 boolean canIgnore() {
3321 switch (sym.kind) {
3322 case ABSENT_MTH:
3323 return true;
3324 case WRONG_MTH:
3325 InapplicableSymbolError errSym =
3326 (InapplicableSymbolError)sym.baseSymbol();
3327 return new Template(MethodCheckDiag.ARITY_MISMATCH.regex())
3328 .matches(errSym.errCandidate().snd);
3329 case WRONG_MTHS:
3330 InapplicableSymbolsError errSyms =
3331 (InapplicableSymbolsError)sym.baseSymbol();
3332 return errSyms.filterCandidates(errSyms.mapCandidates()).isEmpty();
3333 default:
3334 return false;
3335 }
3336 }
3337
3338 static ReferenceLookupResult error(Symbol sym) {
3339 return new ReferenceLookupResult(sym, StaticKind.UNDEFINED);
3340 }
3341 }
3342
3343 /**
3344 * This abstract class embodies the logic that converts one (bound lookup) or two (unbound lookup)
3345 * {@code ReferenceLookupResult} objects into a {@code Symbol}, which is then regarded as the
3346 * result of method reference resolution.
3347 */
3348 abstract class ReferenceChooser {
3349 /**
3350 * Generate a result from a pair of lookup result objects. This method delegates to the
3351 * appropriate result generation routine.
3352 */
3353 ReferenceLookupResult result(ReferenceLookupResult boundRes, ReferenceLookupResult unboundRes) {
3354 return unboundRes != referenceNotFound ?
3355 unboundResult(boundRes, unboundRes) :
3356 boundResult(boundRes);
3357 }
3358
3359 /**
3360 * Generate a symbol from a given bound lookup result.
3361 */
3362 abstract ReferenceLookupResult boundResult(ReferenceLookupResult boundRes);
3363
3364 /**
3365 * Generate a symbol from a pair of bound/unbound lookup results.
3366 */
3367 abstract ReferenceLookupResult unboundResult(ReferenceLookupResult boundRes, ReferenceLookupResult unboundRes);
3368 }
3369
3370 /**
3371 * This chooser implements the selection strategy used during a full lookup; this logic
3372 * is described in JLS SE 8 (15.3.2).
3373 */
3374 ReferenceChooser basicReferenceChooser = new ReferenceChooser() {
3375
3376 @Override
3377 ReferenceLookupResult boundResult(ReferenceLookupResult boundRes) {
3378 return !boundRes.isSuccess() || boundRes.hasKind(StaticKind.NON_STATIC) ?
3379 boundRes : //the search produces a non-static method
3380 ReferenceLookupResult.error(new BadMethodReferenceError(boundRes.sym, false));
3381 }
3382
3383 @Override
3384 ReferenceLookupResult unboundResult(ReferenceLookupResult boundRes, ReferenceLookupResult unboundRes) {
3385 if (boundRes.isSuccess() && boundRes.sym.isStatic() &&
3386 (!unboundRes.isSuccess() || unboundRes.hasKind(StaticKind.STATIC))) {
3387 //the first search produces a static method and no non-static method is applicable
3388 //during the second search
3389 return boundRes;
3390 } else if (unboundRes.isSuccess() && !unboundRes.sym.isStatic() &&
3391 (!boundRes.isSuccess() || boundRes.hasKind(StaticKind.NON_STATIC))) {
3392 //the second search produces a non-static method and no static method is applicable
3393 //during the first search
3394 return unboundRes;
3395 } else if (boundRes.isSuccess() && unboundRes.isSuccess()) {
3396 //both searches produce some result; ambiguity (error recovery)
3397 return ReferenceLookupResult.error(ambiguityError(boundRes.sym, unboundRes.sym));
3398 } else if (boundRes.isSuccess() || unboundRes.isSuccess()) {
3399 //Both searches failed to produce a result with correct staticness (i.e. first search
3400 //produces an non-static method). Alternatively, a given search produced a result
3401 //with the right staticness, but the other search has applicable methods with wrong
3402 //staticness (error recovery)
3403 return ReferenceLookupResult.error(new BadMethodReferenceError(boundRes.isSuccess() ?
3404 boundRes.sym : unboundRes.sym, true));
3405 } else {
3406 //both searches fail to produce a result - pick 'better' error using heuristics (error recovery)
3407 return (boundRes.canIgnore() && !unboundRes.canIgnore()) ?
3408 unboundRes : boundRes;
3409 }
3410 }
3411 };
3412
3413 /**
3414 * This chooser implements the selection strategy used during an arity-based lookup; this logic
3415 * is described in JLS SE 8 (15.12.2.1).
3416 */
3417 ReferenceChooser structuralReferenceChooser = new ReferenceChooser() {
3418
3419 @Override
3420 ReferenceLookupResult boundResult(ReferenceLookupResult boundRes) {
3421 return (!boundRes.isSuccess() || !boundRes.hasKind(StaticKind.STATIC)) ?
3422 boundRes : //the search has at least one applicable non-static method
3423 ReferenceLookupResult.error(new BadMethodReferenceError(boundRes.sym, false));
3424 }
3425
3426 @Override
3427 ReferenceLookupResult unboundResult(ReferenceLookupResult boundRes, ReferenceLookupResult unboundRes) {
3428 if (boundRes.isSuccess() && !boundRes.hasKind(StaticKind.NON_STATIC)) {
3429 //the first search has at least one applicable static method
3430 return boundRes;
3431 } else if (unboundRes.isSuccess() && !unboundRes.hasKind(StaticKind.STATIC)) {
3432 //the second search has at least one applicable non-static method
3433 return unboundRes;
3434 } else if (boundRes.isSuccess() || unboundRes.isSuccess()) {
3435 //either the first search produces a non-static method, or second search produces
3436 //a non-static method (error recovery)
3437 return ReferenceLookupResult.error(new BadMethodReferenceError(boundRes.isSuccess() ?
3438 boundRes.sym : unboundRes.sym, true));
3439 } else {
3440 //both searches fail to produce a result - pick 'better' error using heuristics (error recovery)
3441 return (boundRes.canIgnore() && !unboundRes.canIgnore()) ?
3442 unboundRes : boundRes;
3443 }
3444 }
3445 };
3446
3447 /**
3448 * Helper for defining custom method-like lookup logic; a lookup helper
3449 * provides hooks for (i) the actual lookup logic and (ii) accessing the
3450 * lookup result (this step might result in compiler diagnostics to be generated)
3451 */
3452 abstract class LookupHelper {
3453
3454 /** name of the symbol to lookup */
3455 Name name;
3456
3457 /** location in which the lookup takes place */
3458 Type site;
3459
3460 /** actual types used during the lookup */
3461 List<Type> argtypes;
3462
3463 /** type arguments used during the lookup */
3464 List<Type> typeargtypes;
3465
3466 /** Max overload resolution phase handled by this helper */
3467 MethodResolutionPhase maxPhase;
3468
3469 LookupHelper(Name name, Type site, List<Type> argtypes, List<Type> typeargtypes, MethodResolutionPhase maxPhase) {
3470 this.name = name;
3471 this.site = site;
3472 this.argtypes = argtypes;
3473 this.typeargtypes = typeargtypes;
3474 this.maxPhase = maxPhase;
3475 }
3476
3477 /**
3478 * Should lookup stop at given phase with given result
3479 */
3480 final boolean shouldStop(Symbol sym, MethodResolutionPhase phase) {
3481 return phase.ordinal() > maxPhase.ordinal() ||
3482 !sym.kind.isResolutionError() || sym.kind == AMBIGUOUS || sym.kind == STATICERR;
3483 }
3484
3485 /**
3486 * Search for a symbol under a given overload resolution phase - this method
3487 * is usually called several times, once per each overload resolution phase
3488 */
3489 abstract Symbol lookup(Env<AttrContext> env, MethodResolutionPhase phase);
3490
3491 /**
3492 * Dump overload resolution info
3493 */
3494 void debug(DiagnosticPosition pos, Symbol sym) {
3495 //do nothing
3496 }
3497
3498 /**
3499 * Validate the result of the lookup
3500 */
3501 abstract Symbol access(Env<AttrContext> env, DiagnosticPosition pos, Symbol location, Symbol sym);
3502 }
3503
3504 abstract class BasicLookupHelper extends LookupHelper {
3505
3506 BasicLookupHelper(Name name, Type site, List<Type> argtypes, List<Type> typeargtypes) {
3507 this(name, site, argtypes, typeargtypes, MethodResolutionPhase.VARARITY);
3508 }
3509
3510 BasicLookupHelper(Name name, Type site, List<Type> argtypes, List<Type> typeargtypes, MethodResolutionPhase maxPhase) {
3511 super(name, site, argtypes, typeargtypes, maxPhase);
3512 }
3513
3514 @Override
3515 final Symbol lookup(Env<AttrContext> env, MethodResolutionPhase phase) {
3516 Symbol sym = doLookup(env, phase);
3517 if (sym.kind == AMBIGUOUS) {
3518 AmbiguityError a_err = (AmbiguityError)sym.baseSymbol();
3519 sym = a_err.mergeAbstracts(site);
3520 }
3521 return sym;
3522 }
3523
3524 abstract Symbol doLookup(Env<AttrContext> env, MethodResolutionPhase phase);
3525
3526 @Override
3527 Symbol access(Env<AttrContext> env, DiagnosticPosition pos, Symbol location, Symbol sym) {
3528 if (sym.kind.isResolutionError()) {
3529 //if nothing is found return the 'first' error
3530 sym = accessMethod(sym, pos, location, site, name, true, argtypes, typeargtypes);
3531 }
3532 return sym;
3533 }
3534
3535 @Override
3536 void debug(DiagnosticPosition pos, Symbol sym) {
3537 reportVerboseResolutionDiagnostic(pos, name, site, argtypes, typeargtypes, sym);
3538 }
3539 }
3540
3541 /**
3542 * Helper class for member reference lookup. A reference lookup helper
3543 * defines the basic logic for member reference lookup; a method gives
3544 * access to an 'unbound' helper used to perform an unbound member
3545 * reference lookup.
3546 */
3547 abstract class ReferenceLookupHelper extends LookupHelper {
3548
3549 /** The member reference tree */
3550 JCMemberReference referenceTree;
3551
3552 ReferenceLookupHelper(JCMemberReference referenceTree, Name name, Type site,
3553 List<Type> argtypes, List<Type> typeargtypes, MethodResolutionPhase maxPhase) {
3554 super(name, site, argtypes, typeargtypes, maxPhase);
3555 this.referenceTree = referenceTree;
3556 }
3557
3558 /**
3559 * Returns an unbound version of this lookup helper. By default, this
3560 * method returns an dummy lookup helper.
3561 */
3562 ReferenceLookupHelper unboundLookup(InferenceContext inferenceContext) {
3563 return null;
3564 }
3565
3566 /**
3567 * Get the kind of the member reference
3568 */
3569 abstract JCMemberReference.ReferenceKind referenceKind(Symbol sym);
3570
3571 Symbol access(Env<AttrContext> env, DiagnosticPosition pos, Symbol location, Symbol sym) {
3572 if (sym.kind == AMBIGUOUS) {
3573 AmbiguityError a_err = (AmbiguityError)sym.baseSymbol();
3574 sym = a_err.mergeAbstracts(site);
3575 }
3576 //skip error reporting
3577 return sym;
3578 }
3579 }
3580
3581 /**
3582 * Helper class for method reference lookup. The lookup logic is based
3583 * upon Resolve.findMethod; in certain cases, this helper class has a
3584 * corresponding unbound helper class (see UnboundMethodReferenceLookupHelper).
3585 * In such cases, non-static lookup results are thrown away.
3586 */
3587 class MethodReferenceLookupHelper extends ReferenceLookupHelper {
3588
3589 /** The original method reference lookup site. */
3590 Type originalSite;
3591
3592 MethodReferenceLookupHelper(JCMemberReference referenceTree, Name name, Type site,
3593 List<Type> argtypes, List<Type> typeargtypes, MethodResolutionPhase maxPhase) {
3594 super(referenceTree, name, types.skipTypeVars(site, true), argtypes, typeargtypes, maxPhase);
3595 this.originalSite = site;
3596 }
3597
3598 @Override
3599 final Symbol lookup(Env<AttrContext> env, MethodResolutionPhase phase) {
3600 return findMethod(env, site, name, argtypes, typeargtypes,
3601 phase.isBoxingRequired(), phase.isVarargsRequired());
3602 }
3603
3604 @Override
3605 ReferenceLookupHelper unboundLookup(InferenceContext inferenceContext) {
3606 if (TreeInfo.isStaticSelector(referenceTree.expr, names)) {
3607 if (argtypes.nonEmpty() &&
3608 (argtypes.head.hasTag(NONE) ||
3609 types.isSubtypeUnchecked(inferenceContext.asUndetVar(argtypes.head), originalSite))) {
3610 return new UnboundMethodReferenceLookupHelper(referenceTree, name,
3611 originalSite, argtypes, typeargtypes, maxPhase);
3612 } else {
3613 return new ReferenceLookupHelper(referenceTree, name, site, argtypes, typeargtypes, maxPhase) {
3614 @Override
3615 ReferenceLookupHelper unboundLookup(InferenceContext inferenceContext) {
3616 return this;
3617 }
3618
3619 @Override
3620 Symbol lookup(Env<AttrContext> env, MethodResolutionPhase phase) {
3621 return methodNotFound;
3622 }
3623
3624 @Override
3625 ReferenceKind referenceKind(Symbol sym) {
3626 Assert.error();
3627 return null;
3628 }
3629 };
3630 }
3631 } else {
3632 return super.unboundLookup(inferenceContext);
3633 }
3634 }
3635
3636 @Override
3637 ReferenceKind referenceKind(Symbol sym) {
3638 if (sym.isStatic()) {
3639 return ReferenceKind.STATIC;
3640 } else {
3641 Name selName = TreeInfo.name(referenceTree.getQualifierExpression());
3642 return selName != null && selName == names._super ?
3643 ReferenceKind.SUPER :
3644 ReferenceKind.BOUND;
3645 }
3646 }
3647
3648 @Override
3649 Symbol access(Env<AttrContext> env, DiagnosticPosition pos, Symbol location, Symbol sym) {
3650 if (originalSite.hasTag(TYPEVAR) && sym.kind == MTH) {
3651 sym = (sym.flags() & Flags.PRIVATE) != 0 ?
3652 new AccessError(env, site, sym) :
3653 sym;
3654 return accessBase(sym, pos, location, originalSite, name, true);
3655 } else {
3656 return super.access(env, pos, location, sym);
3657 }
3658 }
3659 }
3660
3661 /**
3662 * Helper class for unbound method reference lookup. Essentially the same
3663 * as the basic method reference lookup helper; main difference is that static
3664 * lookup results are thrown away. If qualifier type is raw, an attempt to
3665 * infer a parameterized type is made using the first actual argument (that
3666 * would otherwise be ignored during the lookup).
3667 */
3668 class UnboundMethodReferenceLookupHelper extends MethodReferenceLookupHelper {
3669
3670 UnboundMethodReferenceLookupHelper(JCMemberReference referenceTree, Name name, Type site,
3671 List<Type> argtypes, List<Type> typeargtypes, MethodResolutionPhase maxPhase) {
3672 super(referenceTree, name, site, argtypes.tail, typeargtypes, maxPhase);
3673 if (site.isRaw() && !argtypes.head.hasTag(NONE)) {
3674 Type asSuperSite = types.asSuper(argtypes.head, site.tsym);
3675 this.site = types.skipTypeVars(asSuperSite, true);
3676 }
3677 }
3678
3679 @Override
3680 ReferenceLookupHelper unboundLookup(InferenceContext inferenceContext) {
3681 return this;
3682 }
3683
3684 @Override
3685 ReferenceKind referenceKind(Symbol sym) {
3686 return ReferenceKind.UNBOUND;
3687 }
3688 }
3689
3690 /**
3691 * Helper class for array constructor lookup; an array constructor lookup
3692 * is simulated by looking up a method that returns the array type specified
3693 * as qualifier, and that accepts a single int parameter (size of the array).
3694 */
3695 class ArrayConstructorReferenceLookupHelper extends ReferenceLookupHelper {
3696
3697 ArrayConstructorReferenceLookupHelper(JCMemberReference referenceTree, Type site, List<Type> argtypes,
3698 List<Type> typeargtypes, MethodResolutionPhase maxPhase) {
3699 super(referenceTree, names.init, site, argtypes, typeargtypes, maxPhase);
3700 }
3701
3702 @Override
3703 protected Symbol lookup(Env<AttrContext> env, MethodResolutionPhase phase) {
3704 WriteableScope sc = WriteableScope.create(syms.arrayClass);
3705 MethodSymbol arrayConstr = new MethodSymbol(PUBLIC, name, null, site.tsym);
3706 arrayConstr.type = new MethodType(List.of(syms.intType), site, List.nil(), syms.methodClass);
3707 sc.enter(arrayConstr);
3708 return findMethodInScope(env, site, name, argtypes, typeargtypes, sc, methodNotFound, phase.isBoxingRequired(), phase.isVarargsRequired(), false);
3709 }
3710
3711 @Override
3712 ReferenceKind referenceKind(Symbol sym) {
3713 return ReferenceKind.ARRAY_CTOR;
3714 }
3715 }
3716
3717 /**
3718 * Helper class for constructor reference lookup. The lookup logic is based
3719 * upon either Resolve.findMethod or Resolve.findDiamond - depending on
3720 * whether the constructor reference needs diamond inference (this is the case
3721 * if the qualifier type is raw). A special erroneous symbol is returned
3722 * if the lookup returns the constructor of an inner class and there's no
3723 * enclosing instance in scope.
3724 */
3725 class ConstructorReferenceLookupHelper extends ReferenceLookupHelper {
3726
3727 boolean needsInference;
3728
3729 ConstructorReferenceLookupHelper(JCMemberReference referenceTree, Type site, List<Type> argtypes,
3730 List<Type> typeargtypes, MethodResolutionPhase maxPhase) {
3731 super(referenceTree, names.init, site, argtypes, typeargtypes, maxPhase);
3732 if (site.isRaw()) {
3733 this.site = new ClassType(site.getEnclosingType(),
3734 !(site.tsym.isInner() && site.getEnclosingType().isRaw()) ?
3735 site.tsym.type.getTypeArguments() : List.nil(), site.tsym, site.getMetadata());
3736 needsInference = true;
3737 }
3738 }
3739
3740 @Override
3741 protected Symbol lookup(Env<AttrContext> env, MethodResolutionPhase phase) {
3742 Symbol sym = needsInference ?
3743 findDiamond(env, site, argtypes, typeargtypes, phase.isBoxingRequired(), phase.isVarargsRequired()) :
3744 findMethod(env, site, name, argtypes, typeargtypes,
3745 phase.isBoxingRequired(), phase.isVarargsRequired());
3746 return enclosingInstanceMissing(env, site) ? new BadConstructorReferenceError(sym) : sym;
3747 }
3748
3749 @Override
3750 ReferenceKind referenceKind(Symbol sym) {
3751 return site.getEnclosingType().hasTag(NONE) ?
3752 ReferenceKind.TOPLEVEL : ReferenceKind.IMPLICIT_INNER;
3753 }
3754 }
3755
3756 /**
3757 * Main overload resolution routine. On each overload resolution step, a
3758 * lookup helper class is used to perform the method/constructor lookup;
3759 * at the end of the lookup, the helper is used to validate the results
3760 * (this last step might trigger overload resolution diagnostics).
3761 */
3762 Symbol lookupMethod(Env<AttrContext> env, DiagnosticPosition pos, Symbol location, MethodCheck methodCheck, LookupHelper lookupHelper) {
3763 MethodResolutionContext resolveContext = new MethodResolutionContext();
3764 resolveContext.methodCheck = methodCheck;
3765 return lookupMethod(env, pos, location, resolveContext, lookupHelper);
3766 }
3767
3768 Symbol lookupMethod(Env<AttrContext> env, DiagnosticPosition pos, Symbol location,
3769 MethodResolutionContext resolveContext, LookupHelper lookupHelper) {
3770 MethodResolutionContext prevResolutionContext = currentResolutionContext;
3771 try {
3772 Symbol bestSoFar = methodNotFound;
3773 currentResolutionContext = resolveContext;
3774 for (MethodResolutionPhase phase : methodResolutionSteps) {
3775 if (lookupHelper.shouldStop(bestSoFar, phase))
3776 break;
3777 MethodResolutionPhase prevPhase = currentResolutionContext.step;
3778 Symbol prevBest = bestSoFar;
3779 currentResolutionContext.step = phase;
3780 Symbol sym = lookupHelper.lookup(env, phase);
3781 lookupHelper.debug(pos, sym);
3782 bestSoFar = phase.mergeResults(bestSoFar, sym);
3783 env.info.pendingResolutionPhase = (prevBest == bestSoFar) ? prevPhase : phase;
3784 }
3785 return lookupHelper.access(env, pos, location, bestSoFar);
3786 } finally {
3787 currentResolutionContext = prevResolutionContext;
3788 }
3789 }
3790
3791 /**
3792 * Resolve `c.name' where name == this or name == super.
3793 * @param pos The position to use for error reporting.
3794 * @param env The environment current at the expression.
3795 * @param c The qualifier.
3796 * @param name The identifier's name.
3797 */
3798 Symbol resolveSelf(DiagnosticPosition pos,
3799 Env<AttrContext> env,
3800 TypeSymbol c,
3801 Name name) {
3802 Assert.check(name == names._this || name == names._super);
3803 Env<AttrContext> env1 = env;
3804 boolean staticOnly = false;
3805 while (env1.outer != null) {
3806 if (isStatic(env1)) staticOnly = true;
3807 if (env1.enclClass.sym == c) {
3808 Symbol sym = env1.info.scope.findFirst(name);
3809 if (sym != null) {
3810 if (staticOnly)
3811 sym = new StaticError(sym);
3812 else if (env1.info.ctorPrologue && !isAllowedEarlyReference(pos, env1, (VarSymbol)sym))
3813 sym = new RefBeforeCtorCalledError(sym);
3814 return accessBase(sym, pos, env.enclClass.sym.type,
3815 name, true);
3816 }
3817 }
3818 if ((env1.enclClass.sym.flags() & STATIC) != 0) staticOnly = true;
3819 env1 = env1.outer;
3820 }
3821 if (c.isInterface() &&
3822 name == names._super && !isStatic(env) &&
3823 types.isDirectSuperInterface(c, env.enclClass.sym)) {
3824 //this might be a default super call if one of the superinterfaces is 'c'
3825 for (Type t : pruneInterfaces(env.enclClass.type)) {
3826 if (t.tsym == c) {
3827 if (env.info.ctorPrologue)
3828 log.error(pos, Errors.CantRefBeforeCtorCalled(name));
3829 env.info.defaultSuperCallSite = t;
3830 return new VarSymbol(0, names._super,
3831 types.asSuper(env.enclClass.type, c), env.enclClass.sym);
3832 }
3833 }
3834 //find a direct supertype that is a subtype of 'c'
3835 for (Type i : types.directSupertypes(env.enclClass.type)) {
3836 if (i.tsym.isSubClass(c, types) && i.tsym != c) {
3837 log.error(pos,
3838 Errors.IllegalDefaultSuperCall(c,
3839 Fragments.RedundantSupertype(c, i)));
3840 return syms.errSymbol;
3841 }
3842 }
3843 Assert.error();
3844 }
3845 log.error(pos, Errors.NotEnclClass(c));
3846 return syms.errSymbol;
3847 }
3848 //where
3849 private List<Type> pruneInterfaces(Type t) {
3850 ListBuffer<Type> result = new ListBuffer<>();
3851 for (Type t1 : types.interfaces(t)) {
3852 boolean shouldAdd = true;
3853 for (Type t2 : types.directSupertypes(t)) {
3854 if (t1 != t2 && !t2.hasTag(ERROR) && types.isSubtypeNoCapture(t2, t1)) {
3855 shouldAdd = false;
3856 }
3857 }
3858 if (shouldAdd) {
3859 result.append(t1);
3860 }
3861 }
3862 return result.toList();
3863 }
3864
3865 /**
3866 * Determine if an early instance field reference may appear in a constructor prologue.
3867 *
3868 * <p>
3869 * This is only allowed when:
3870 * - The field is being assigned a value (i.e., written but not read)
3871 * - The field is not inherited from a superclass
3872 * - The assignment is not within a lambda, because that would require
3873 * capturing 'this' which is not allowed prior to super().
3874 *
3875 * <p>
3876 * Note, this method doesn't catch all such scenarios, because this method
3877 * is invoked for symbol "x" only for "x = 42" but not for "this.x = 42".
3878 * We also don't verify that the field has no initializer, which is required.
3879 * To catch those cases, we rely on similar logic in Attr.checkAssignable().
3880 */
3881 private boolean isAllowedEarlyReference(DiagnosticPosition pos, Env<AttrContext> env, VarSymbol v) {
3882
3883 // Check assumptions
3884 Assert.check(env.info.ctorPrologue);
3885 Assert.check((v.flags_field & STATIC) == 0);
3886
3887 // The symbol must appear in the LHS of an assignment statement
3888 if (!(env.tree instanceof JCAssign assign))
3889 return false;
3890
3891 // The assignment statement must not be within a lambda
3892 if (env.info.isLambda)
3893 return false;
3894
3895 // Get the symbol's qualifier, if any
3896 JCExpression lhs = TreeInfo.skipParens(assign.lhs);
3897 JCExpression base;
3898 switch (lhs.getTag()) {
3899 case IDENT:
3900 base = null;
3901 break;
3902 case SELECT:
3903 JCFieldAccess select = (JCFieldAccess)lhs;
3904 base = select.selected;
3905 if (!TreeInfo.isExplicitThisReference(types, (ClassType)env.enclClass.type, base))
3906 return false;
3907 break;
3908 default:
3909 return false;
3910 }
3911
3912 // If an early reference, the field must not be declared in a superclass
3913 if (isEarlyReference(env, base, v) && v.owner != env.enclClass.sym)
3914 return false;
3915
3916 // The flexible constructors feature must be enabled
3917 preview.checkSourceLevel(pos, Feature.FLEXIBLE_CONSTRUCTORS);
3918
3919 // OK
3920 return true;
3921 }
3922
3923 /**
3924 * Determine if the variable appearance constitutes an early reference to the current class.
3925 *
3926 * <p>
3927 * This means the variable is an instance field of the current class and it appears
3928 * in an early initialization context of it (i.e., one of its constructor prologues).
3929 *
3930 * <p>
3931 * Such a reference is only allowed for assignments to non-initialized fields that are
3932 * not inherited from a superclass, though that is not enforced by this method.
3933 *
3934 * @param env The current environment
3935 * @param base Variable qualifier, if any, otherwise null
3936 * @param v The variable
3937 */
3938 public boolean isEarlyReference(Env<AttrContext> env, JCTree base, VarSymbol v) {
3939 return env.info.ctorPrologue &&
3940 (v.flags() & STATIC) == 0 &&
3941 v.owner.kind == TYP &&
3942 types.isSubtype(env.enclClass.type, v.owner.type) &&
3943 (base == null || TreeInfo.isExplicitThisReference(types, (ClassType)env.enclClass.type, base));
3944 }
3945
3946 /**
3947 * Resolve `c.this' for an enclosing class c that contains the
3948 * named member.
3949 * @param pos The position to use for error reporting.
3950 * @param env The environment current at the expression.
3951 * @param member The member that must be contained in the result.
3952 */
3953 Symbol resolveSelfContaining(DiagnosticPosition pos,
3954 Env<AttrContext> env,
3955 Symbol member,
3956 boolean isSuperCall) {
3957 Symbol sym = resolveSelfContainingInternal(env, member, isSuperCall);
3958 if (sym == null) {
3959 log.error(pos, Errors.EnclClassRequired(member));
3960 return syms.errSymbol;
3961 } else {
3962 return accessBase(sym, pos, env.enclClass.sym.type, sym.name, true);
3963 }
3964 }
3965
3966 boolean enclosingInstanceMissing(Env<AttrContext> env, Type type) {
3967 if (type.hasTag(CLASS) && type.getEnclosingType().hasTag(CLASS)) {
3968 Symbol encl = resolveSelfContainingInternal(env, type.tsym, false);
3969 return encl == null || encl.kind.isResolutionError();
3970 }
3971 return false;
3972 }
3973
3974 private Symbol resolveSelfContainingInternal(Env<AttrContext> env,
3975 Symbol member,
3976 boolean isSuperCall) {
3977 Name name = names._this;
3978 Env<AttrContext> env1 = isSuperCall ? env.outer : env;
3979 boolean staticOnly = false;
3980 if (env1 != null) {
3981 while (env1 != null && env1.outer != null) {
3982 if (isStatic(env1)) staticOnly = true;
3983 if (env1.enclClass.sym.isSubClass(member.owner.enclClass(), types)) {
3984 Symbol sym = env1.info.scope.findFirst(name);
3985 if (sym != null) {
3986 if (staticOnly) sym = new StaticError(sym);
3987 return sym;
3988 }
3989 }
3990 if ((env1.enclClass.sym.flags() & STATIC) != 0)
3991 staticOnly = true;
3992 env1 = env1.outer;
3993 }
3994 }
3995 return null;
3996 }
3997
3998 /**
3999 * Resolve an appropriate implicit this instance for t's container.
4000 * JLS 8.8.5.1 and 15.9.2
4001 */
4002 Type resolveImplicitThis(DiagnosticPosition pos, Env<AttrContext> env, Type t) {
4003 return resolveImplicitThis(pos, env, t, false);
4004 }
4005
4006 Type resolveImplicitThis(DiagnosticPosition pos, Env<AttrContext> env, Type t, boolean isSuperCall) {
4007 Type thisType = (t.tsym.owner.kind.matches(KindSelector.VAL_MTH)
4008 ? resolveSelf(pos, env, t.getEnclosingType().tsym, names._this)
4009 : resolveSelfContaining(pos, env, t.tsym, isSuperCall)).type;
4010 if (env.info.ctorPrologue && thisType.tsym == env.enclClass.sym) {
4011 log.error(pos, Errors.CantRefBeforeCtorCalled(names._this));
4012 }
4013 return thisType;
4014 }
4015
4016 /* ***************************************************************************
4017 * ResolveError classes, indicating error situations when accessing symbols
4018 ****************************************************************************/
4019
4020 //used by TransTypes when checking target type of synthetic cast
4021 public void logAccessErrorInternal(Env<AttrContext> env, JCTree tree, Type type) {
4022 AccessError error = new AccessError(env, env.enclClass.type, type.tsym);
4023 logResolveError(error, tree.pos(), env.enclClass.sym, env.enclClass.type, null, null, null);
4024 }
4025 //where
4026 private void logResolveError(ResolveError error,
4027 DiagnosticPosition pos,
4028 Symbol location,
4029 Type site,
4030 Name name,
4031 List<Type> argtypes,
4032 List<Type> typeargtypes) {
4033 JCDiagnostic d = error.getDiagnostic(JCDiagnostic.DiagnosticType.ERROR,
4034 pos, location, site, name, argtypes, typeargtypes);
4035 if (d != null) {
4036 d.setFlag(DiagnosticFlag.RESOLVE_ERROR);
4037 log.report(d);
4038 }
4039 }
4040
4041 private final LocalizedString noArgs = new LocalizedString("compiler.misc.no.args");
4042
4043 public Object methodArguments(List<Type> argtypes) {
4044 if (argtypes == null || argtypes.isEmpty()) {
4045 return noArgs;
4046 } else {
4047 ListBuffer<Object> diagArgs = new ListBuffer<>();
4048 for (Type t : argtypes) {
4049 if (t.hasTag(DEFERRED)) {
4050 diagArgs.append(((DeferredAttr.DeferredType)t).tree);
4051 } else {
4052 diagArgs.append(t);
4053 }
4054 }
4055 return diagArgs;
4056 }
4057 }
4058
4059 /** check if a type is a subtype of Serializable, if that is available.*/
4060 boolean isSerializable(Type t) {
4061 try {
4062 syms.serializableType.complete();
4063 }
4064 catch (CompletionFailure e) {
4065 return false;
4066 }
4067 return types.isSubtype(t, syms.serializableType);
4068 }
4069
4070 /**
4071 * Root class for resolution errors. Subclass of ResolveError
4072 * represent a different kinds of resolution error - as such they must
4073 * specify how they map into concrete compiler diagnostics.
4074 */
4075 abstract class ResolveError extends Symbol {
4076
4077 /** The name of the kind of error, for debugging only. */
4078 final String debugName;
4079
4080 ResolveError(Kind kind, String debugName) {
4081 super(kind, 0, null, null, null);
4082 this.debugName = debugName;
4083 }
4084
4085 @Override @DefinedBy(Api.LANGUAGE_MODEL)
4086 public <R, P> R accept(ElementVisitor<R, P> v, P p) {
4087 throw new AssertionError();
4088 }
4089
4090 @Override
4091 public String toString() {
4092 return debugName;
4093 }
4094
4095 @Override
4096 public boolean exists() {
4097 return false;
4098 }
4099
4100 @Override
4101 public boolean isStatic() {
4102 return false;
4103 }
4104
4105 /**
4106 * Create an external representation for this erroneous symbol to be
4107 * used during attribution - by default this returns the symbol of a
4108 * brand new error type which stores the original type found
4109 * during resolution.
4110 *
4111 * @param name the name used during resolution
4112 * @param location the location from which the symbol is accessed
4113 */
4114 protected Symbol access(Name name, TypeSymbol location) {
4115 return types.createErrorType(name, location, syms.errSymbol.type).tsym;
4116 }
4117
4118 /**
4119 * Create a diagnostic representing this resolution error.
4120 *
4121 * @param dkind The kind of the diagnostic to be created (e.g error).
4122 * @param pos The position to be used for error reporting.
4123 * @param site The original type from where the selection took place.
4124 * @param name The name of the symbol to be resolved.
4125 * @param argtypes The invocation's value arguments,
4126 * if we looked for a method.
4127 * @param typeargtypes The invocation's type arguments,
4128 * if we looked for a method.
4129 */
4130 abstract JCDiagnostic getDiagnostic(JCDiagnostic.DiagnosticType dkind,
4131 DiagnosticPosition pos,
4132 Symbol location,
4133 Type site,
4134 Name name,
4135 List<Type> argtypes,
4136 List<Type> typeargtypes);
4137 }
4138
4139 /**
4140 * This class is the root class of all resolution errors caused by
4141 * an invalid symbol being found during resolution.
4142 */
4143 abstract class InvalidSymbolError extends ResolveError {
4144
4145 /** The invalid symbol found during resolution */
4146 Symbol sym;
4147
4148 InvalidSymbolError(Kind kind, Symbol sym, String debugName) {
4149 super(kind, debugName);
4150 this.sym = sym;
4151 }
4152
4153 @Override
4154 public boolean exists() {
4155 return true;
4156 }
4157
4158 @Override
4159 public String toString() {
4160 return super.toString() + " wrongSym=" + sym;
4161 }
4162
4163 @Override
4164 public Symbol access(Name name, TypeSymbol location) {
4165 if (!sym.kind.isResolutionError() && sym.kind.matches(KindSelector.TYP))
4166 return types.createErrorType(name, location, sym.type).tsym;
4167 else
4168 return sym;
4169 }
4170 }
4171
4172 class BadRestrictedTypeError extends ResolveError {
4173 private final Name typeName;
4174 BadRestrictedTypeError(Name typeName) {
4175 super(Kind.BAD_RESTRICTED_TYPE, "bad var use");
4176 this.typeName = typeName;
4177 }
4178
4179 @Override
4180 JCDiagnostic getDiagnostic(DiagnosticType dkind, DiagnosticPosition pos, Symbol location, Type site, Name name, List<Type> argtypes, List<Type> typeargtypes) {
4181 return diags.create(dkind, log.currentSource(), pos, "illegal.ref.to.restricted.type", typeName);
4182 }
4183 }
4184
4185 /**
4186 * InvalidSymbolError error class indicating that a symbol matching a
4187 * given name does not exists in a given site.
4188 */
4189 class SymbolNotFoundError extends ResolveError {
4190
4191 SymbolNotFoundError(Kind kind) {
4192 this(kind, "symbol not found error");
4193 }
4194
4195 SymbolNotFoundError(Kind kind, String debugName) {
4196 super(kind, debugName);
4197 }
4198
4199 @Override
4200 JCDiagnostic getDiagnostic(JCDiagnostic.DiagnosticType dkind,
4201 DiagnosticPosition pos,
4202 Symbol location,
4203 Type site,
4204 Name name,
4205 List<Type> argtypes,
4206 List<Type> typeargtypes) {
4207 argtypes = argtypes == null ? List.nil() : argtypes;
4208 typeargtypes = typeargtypes == null ? List.nil() : typeargtypes;
4209 if (name == names.error)
4210 return null;
4211
4212 boolean hasLocation = false;
4213 if (location == null) {
4214 location = site.tsym;
4215 }
4216 if (!location.name.isEmpty()) {
4217 if (location.kind == PCK && !site.tsym.exists() && location.name != names.java) {
4218 return diags.create(dkind, log.currentSource(), pos,
4219 "doesnt.exist", location);
4220 }
4221 hasLocation = !location.name.equals(names._this) &&
4222 !location.name.equals(names._super);
4223 }
4224 boolean isConstructor = name == names.init;
4225 KindName kindname = isConstructor ? KindName.CONSTRUCTOR : kind.absentKind();
4226 Name idname = isConstructor ? site.tsym.name : name;
4227 String errKey = getErrorKey(kindname, typeargtypes.nonEmpty(), hasLocation);
4228 if (hasLocation) {
4229 return diags.create(dkind, log.currentSource(), pos,
4230 errKey, kindname, idname, //symbol kindname, name
4231 typeargtypes, args(argtypes), //type parameters and arguments (if any)
4232 getLocationDiag(location, site)); //location kindname, type
4233 }
4234 else {
4235 return diags.create(dkind, log.currentSource(), pos,
4236 errKey, kindname, idname, //symbol kindname, name
4237 typeargtypes, args(argtypes)); //type parameters and arguments (if any)
4238 }
4239 }
4240 //where
4241 private Object args(List<Type> args) {
4242 return args.isEmpty() ? args : methodArguments(args);
4243 }
4244
4245 private String getErrorKey(KindName kindname, boolean hasTypeArgs, boolean hasLocation) {
4246 String key = "cant.resolve";
4247 String suffix = hasLocation ? ".location" : "";
4248 switch (kindname) {
4249 case METHOD:
4250 case CONSTRUCTOR: {
4251 suffix += ".args";
4252 suffix += hasTypeArgs ? ".params" : "";
4253 }
4254 }
4255 return key + suffix;
4256 }
4257 private JCDiagnostic getLocationDiag(Symbol location, Type site) {
4258 if (location.kind == VAR) {
4259 return diags.fragment(Fragments.Location1(kindName(location),
4260 location,
4261 location.type));
4262 } else {
4263 return diags.fragment(Fragments.Location(typeKindName(site),
4264 site,
4265 null));
4266 }
4267 }
4268 }
4269
4270 /**
4271 * InvalidSymbolError error class indicating that a given symbol
4272 * (either a method, a constructor or an operand) is not applicable
4273 * given an actual arguments/type argument list.
4274 */
4275 class InapplicableSymbolError extends ResolveError {
4276
4277 protected MethodResolutionContext resolveContext;
4278
4279 InapplicableSymbolError(MethodResolutionContext context) {
4280 this(WRONG_MTH, "inapplicable symbol error", context);
4281 }
4282
4283 protected InapplicableSymbolError(Kind kind, String debugName, MethodResolutionContext context) {
4284 super(kind, debugName);
4285 this.resolveContext = context;
4286 }
4287
4288 @Override
4289 public String toString() {
4290 return super.toString();
4291 }
4292
4293 @Override
4294 public boolean exists() {
4295 return true;
4296 }
4297
4298 @Override
4299 JCDiagnostic getDiagnostic(JCDiagnostic.DiagnosticType dkind,
4300 DiagnosticPosition pos,
4301 Symbol location,
4302 Type site,
4303 Name name,
4304 List<Type> argtypes,
4305 List<Type> typeargtypes) {
4306 if (name == names.error)
4307 return null;
4308
4309 Pair<Symbol, JCDiagnostic> c = errCandidate();
4310 Symbol ws = c.fst.asMemberOf(site, types);
4311 UnaryOperator<JCDiagnostic> rewriter = compactMethodDiags ?
4312 d -> MethodResolutionDiagHelper.rewrite(diags, pos, log.currentSource(), dkind, c.snd) : null;
4313
4314 // If the problem is due to type arguments, then the method parameters aren't relevant,
4315 // so use the error message that omits them to avoid confusion.
4316 switch (c.snd.getCode()) {
4317 case "compiler.misc.wrong.number.type.args":
4318 case "compiler.misc.explicit.param.do.not.conform.to.bounds":
4319 return diags.create(dkind, log.currentSource(), pos,
4320 "cant.apply.symbol.noargs",
4321 rewriter,
4322 kindName(ws),
4323 ws.name == names.init ? ws.owner.name : ws.name,
4324 ws.owner.type,
4325 c.snd);
4326 default:
4327 // Avoid saying "constructor Array in class Array"
4328 if (ws.owner == syms.arrayClass && ws.name == names.init) {
4329 return diags.create(dkind, log.currentSource(), pos,
4330 "cant.apply.array.ctor",
4331 rewriter,
4332 methodArguments(ws.type.getParameterTypes()),
4333 methodArguments(argtypes),
4334 c.snd);
4335 }
4336 return diags.create(dkind, log.currentSource(), pos,
4337 "cant.apply.symbol",
4338 rewriter,
4339 kindName(ws),
4340 ws.name == names.init ? ws.owner.name : ws.name,
4341 methodArguments(ws.type.getParameterTypes()),
4342 methodArguments(argtypes),
4343 kindName(ws.owner),
4344 ws.owner.type,
4345 c.snd);
4346 }
4347 }
4348
4349 @Override
4350 public Symbol access(Name name, TypeSymbol location) {
4351 Pair<Symbol, JCDiagnostic> cand = errCandidate();
4352 TypeSymbol errSymbol = types.createErrorType(name, location, cand != null ? cand.fst.type : syms.errSymbol.type).tsym;
4353 if (cand != null) {
4354 attrRecover.wrongMethodSymbolCandidate(errSymbol, cand.fst, cand.snd);
4355 }
4356 return errSymbol;
4357 }
4358
4359 protected Pair<Symbol, JCDiagnostic> errCandidate() {
4360 Candidate bestSoFar = null;
4361 for (Candidate c : resolveContext.candidates) {
4362 if (c.isApplicable()) continue;
4363 bestSoFar = c;
4364 }
4365 Assert.checkNonNull(bestSoFar);
4366 return new Pair<>(bestSoFar.sym, bestSoFar.details);
4367 }
4368 }
4369
4370 /**
4371 * ResolveError error class indicating that a symbol (either methods, constructors or operand)
4372 * is not applicable given an actual arguments/type argument list.
4373 */
4374 class InapplicableSymbolsError extends InapplicableSymbolError {
4375
4376 InapplicableSymbolsError(MethodResolutionContext context) {
4377 super(WRONG_MTHS, "inapplicable symbols", context);
4378 }
4379
4380 @Override
4381 JCDiagnostic getDiagnostic(JCDiagnostic.DiagnosticType dkind,
4382 DiagnosticPosition pos,
4383 Symbol location,
4384 Type site,
4385 Name name,
4386 List<Type> argtypes,
4387 List<Type> typeargtypes) {
4388 Map<Symbol, JCDiagnostic> candidatesMap = mapCandidates();
4389 Map<Symbol, JCDiagnostic> filteredCandidates = compactMethodDiags ?
4390 filterCandidates(candidatesMap) :
4391 mapCandidates();
4392 if (filteredCandidates.isEmpty()) {
4393 filteredCandidates = candidatesMap;
4394 }
4395 boolean truncatedDiag = candidatesMap.size() != filteredCandidates.size();
4396 if (filteredCandidates.size() > 1) {
4397 JCDiagnostic err = diags.create(dkind,
4398 null,
4399 truncatedDiag ?
4400 EnumSet.of(DiagnosticFlag.COMPRESSED) :
4401 EnumSet.noneOf(DiagnosticFlag.class),
4402 log.currentSource(),
4403 pos,
4404 "cant.apply.symbols",
4405 name == names.init ? KindName.CONSTRUCTOR : kind.absentKind(),
4406 name == names.init ? site.tsym.name : name,
4407 methodArguments(argtypes));
4408 return new JCDiagnostic.MultilineDiagnostic(err, candidateDetails(filteredCandidates, site));
4409 } else if (filteredCandidates.size() == 1) {
4410 Map.Entry<Symbol, JCDiagnostic> _e =
4411 filteredCandidates.entrySet().iterator().next();
4412 final Pair<Symbol, JCDiagnostic> p = new Pair<>(_e.getKey(), _e.getValue());
4413 JCDiagnostic d = new InapplicableSymbolError(resolveContext) {
4414 @Override
4415 protected Pair<Symbol, JCDiagnostic> errCandidate() {
4416 return p;
4417 }
4418 }.getDiagnostic(dkind, pos,
4419 location, site, name, argtypes, typeargtypes);
4420 if (truncatedDiag) {
4421 d.setFlag(DiagnosticFlag.COMPRESSED);
4422 }
4423 return d;
4424 } else {
4425 return new SymbolNotFoundError(ABSENT_MTH).getDiagnostic(dkind, pos,
4426 location, site, name, argtypes, typeargtypes);
4427 }
4428 }
4429 //where
4430 private Map<Symbol, JCDiagnostic> mapCandidates() {
4431 MostSpecificMap candidates = new MostSpecificMap();
4432 for (Candidate c : resolveContext.candidates) {
4433 if (c.isApplicable()) continue;
4434 candidates.put(c);
4435 }
4436 return candidates;
4437 }
4438
4439 @SuppressWarnings("serial")
4440 private class MostSpecificMap extends LinkedHashMap<Symbol, JCDiagnostic> {
4441 private void put(Candidate c) {
4442 ListBuffer<Symbol> overridden = new ListBuffer<>();
4443 for (Symbol s : keySet()) {
4444 if (s == c.sym) {
4445 continue;
4446 }
4447 if (c.sym.overrides(s, (TypeSymbol)s.owner, types, false)) {
4448 overridden.add(s);
4449 } else if (s.overrides(c.sym, (TypeSymbol)c.sym.owner, types, false)) {
4450 return;
4451 }
4452 }
4453 for (Symbol s : overridden) {
4454 remove(s);
4455 }
4456 put(c.sym, c.details);
4457 }
4458 }
4459
4460 Map<Symbol, JCDiagnostic> filterCandidates(Map<Symbol, JCDiagnostic> candidatesMap) {
4461 Map<Symbol, JCDiagnostic> candidates = new LinkedHashMap<>();
4462 for (Map.Entry<Symbol, JCDiagnostic> _entry : candidatesMap.entrySet()) {
4463 JCDiagnostic d = _entry.getValue();
4464 if (!new Template(MethodCheckDiag.ARITY_MISMATCH.regex()).matches(d)) {
4465 candidates.put(_entry.getKey(), d);
4466 }
4467 }
4468 return candidates;
4469 }
4470
4471 private List<JCDiagnostic> candidateDetails(Map<Symbol, JCDiagnostic> candidatesMap, Type site) {
4472 List<JCDiagnostic> details = List.nil();
4473 for (Map.Entry<Symbol, JCDiagnostic> _entry : candidatesMap.entrySet()) {
4474 Symbol sym = _entry.getKey();
4475 JCDiagnostic detailDiag =
4476 diags.fragment(Fragments.InapplicableMethod(Kinds.kindName(sym),
4477 sym.location(site, types),
4478 sym.asMemberOf(site, types),
4479 _entry.getValue()));
4480 details = details.prepend(detailDiag);
4481 }
4482 //typically members are visited in reverse order (see Scope)
4483 //so we need to reverse the candidate list so that candidates
4484 //conform to source order
4485 return details;
4486 }
4487
4488 @Override
4489 protected Pair<Symbol, JCDiagnostic> errCandidate() {
4490 Map<Symbol, JCDiagnostic> candidatesMap = mapCandidates();
4491 Map<Symbol, JCDiagnostic> filteredCandidates = filterCandidates(candidatesMap);
4492 if (filteredCandidates.size() == 1) {
4493 return Pair.of(filteredCandidates.keySet().iterator().next(),
4494 filteredCandidates.values().iterator().next());
4495 }
4496 return null;
4497 }
4498 }
4499
4500 /**
4501 * DiamondError error class indicating that a constructor symbol is not applicable
4502 * given an actual arguments/type argument list using diamond inference.
4503 */
4504 class DiamondError extends InapplicableSymbolError {
4505
4506 Symbol sym;
4507
4508 public DiamondError(Symbol sym, MethodResolutionContext context) {
4509 super(sym.kind, "diamondError", context);
4510 this.sym = sym;
4511 }
4512
4513 JCDiagnostic getDetails() {
4514 return (sym.kind == WRONG_MTH) ?
4515 ((InapplicableSymbolError)sym.baseSymbol()).errCandidate().snd :
4516 null;
4517 }
4518
4519 @Override
4520 JCDiagnostic getDiagnostic(DiagnosticType dkind, DiagnosticPosition pos,
4521 Symbol location, Type site, Name name, List<Type> argtypes, List<Type> typeargtypes) {
4522 JCDiagnostic details = getDetails();
4523 if (details != null && compactMethodDiags) {
4524 JCDiagnostic simpleDiag =
4525 MethodResolutionDiagHelper.rewrite(diags, pos, log.currentSource(), dkind, details);
4526 if (simpleDiag != null) {
4527 return simpleDiag;
4528 }
4529 }
4530 String key = details == null ?
4531 "cant.apply.diamond" :
4532 "cant.apply.diamond.1";
4533 return diags.create(dkind, log.currentSource(), pos, key,
4534 Fragments.Diamond(site.tsym), details);
4535 }
4536 }
4537
4538 /**
4539 * An InvalidSymbolError error class indicating that a symbol is not
4540 * accessible from a given site
4541 */
4542 class AccessError extends InvalidSymbolError {
4543
4544 private Env<AttrContext> env;
4545 private Type site;
4546
4547 AccessError(Env<AttrContext> env, Type site, Symbol sym) {
4548 super(HIDDEN, sym, "access error");
4549 this.env = env;
4550 this.site = site;
4551 }
4552
4553 @Override
4554 public boolean exists() {
4555 return false;
4556 }
4557
4558 @Override
4559 JCDiagnostic getDiagnostic(JCDiagnostic.DiagnosticType dkind,
4560 DiagnosticPosition pos,
4561 Symbol location,
4562 Type site,
4563 Name name,
4564 List<Type> argtypes,
4565 List<Type> typeargtypes) {
4566 if (sym.name == names.init && sym.owner != site.tsym) {
4567 return new SymbolNotFoundError(ABSENT_MTH).getDiagnostic(dkind,
4568 pos, location, site, name, argtypes, typeargtypes);
4569 }
4570 else if ((sym.flags() & PUBLIC) != 0
4571 || (env != null && this.site != null
4572 && !isAccessible(env, this.site))) {
4573 if (sym.owner.kind == PCK) {
4574 return diags.create(dkind, log.currentSource(),
4575 pos, "not.def.access.package.cant.access",
4576 sym, sym.location(), inaccessiblePackageReason(env, sym.packge()));
4577 } else if ( sym.packge() != syms.rootPackage
4578 && !symbolPackageVisible(env, sym)) {
4579 return diags.create(dkind, log.currentSource(),
4580 pos, "not.def.access.class.intf.cant.access.reason",
4581 sym, sym.location(), sym.location().packge(),
4582 inaccessiblePackageReason(env, sym.packge()));
4583 } else {
4584 return diags.create(dkind, log.currentSource(),
4585 pos, "not.def.access.class.intf.cant.access",
4586 sym, sym.location());
4587 }
4588 }
4589 else if ((sym.flags() & (PRIVATE | PROTECTED)) != 0) {
4590 return diags.create(dkind, log.currentSource(),
4591 pos, "report.access", sym,
4592 asFlagSet(sym.flags() & (PRIVATE | PROTECTED)),
4593 sym.location());
4594 }
4595 else {
4596 return diags.create(dkind, log.currentSource(),
4597 pos, "not.def.public.cant.access", sym, sym.location());
4598 }
4599 }
4600
4601 private String toString(Type type) {
4602 StringBuilder sb = new StringBuilder();
4603 sb.append(type);
4604 if (type != null) {
4605 sb.append("[tsym:").append(type.tsym);
4606 if (type.tsym != null)
4607 sb.append("packge:").append(type.tsym.packge());
4608 sb.append("]");
4609 }
4610 return sb.toString();
4611 }
4612 }
4613
4614 class InvisibleSymbolError extends InvalidSymbolError {
4615
4616 private final Env<AttrContext> env;
4617 private final boolean suppressError;
4618
4619 InvisibleSymbolError(Env<AttrContext> env, boolean suppressError, Symbol sym) {
4620 super(HIDDEN, sym, "invisible class error");
4621 this.env = env;
4622 this.suppressError = suppressError;
4623 this.name = sym.name;
4624 }
4625
4626 @Override
4627 JCDiagnostic getDiagnostic(JCDiagnostic.DiagnosticType dkind,
4628 DiagnosticPosition pos,
4629 Symbol location,
4630 Type site,
4631 Name name,
4632 List<Type> argtypes,
4633 List<Type> typeargtypes) {
4634 if (suppressError)
4635 return null;
4636
4637 if (sym.kind == PCK) {
4638 JCDiagnostic details = inaccessiblePackageReason(env, sym.packge());
4639 return diags.create(dkind, log.currentSource(),
4640 pos, "package.not.visible", sym, details);
4641 }
4642
4643 JCDiagnostic details = inaccessiblePackageReason(env, sym.packge());
4644
4645 if (pos.getTree() != null) {
4646 Symbol o = sym;
4647 JCTree tree = pos.getTree();
4648
4649 while (o.kind != PCK && tree.hasTag(SELECT)) {
4650 o = o.owner;
4651 tree = ((JCFieldAccess) tree).selected;
4652 }
4653
4654 if (o.kind == PCK) {
4655 pos = tree.pos();
4656
4657 return diags.create(dkind, log.currentSource(),
4658 pos, "package.not.visible", o, details);
4659 }
4660 }
4661
4662 return diags.create(dkind, log.currentSource(),
4663 pos, "not.def.access.package.cant.access", sym, sym.packge(), details);
4664 }
4665 }
4666
4667 JCDiagnostic inaccessiblePackageReason(Env<AttrContext> env, PackageSymbol sym) {
4668 //no dependency:
4669 if (!env.toplevel.modle.readModules.contains(sym.modle)) {
4670 //does not read:
4671 if (sym.modle != syms.unnamedModule) {
4672 if (env.toplevel.modle != syms.unnamedModule) {
4673 return diags.fragment(Fragments.NotDefAccessDoesNotRead(env.toplevel.modle,
4674 sym,
4675 sym.modle));
4676 } else {
4677 return diags.fragment(Fragments.NotDefAccessDoesNotReadFromUnnamed(sym,
4678 sym.modle));
4679 }
4680 } else {
4681 return diags.fragment(Fragments.NotDefAccessDoesNotReadUnnamed(sym,
4682 env.toplevel.modle));
4683 }
4684 } else {
4685 if (sym.packge().modle.exports.stream().anyMatch(e -> e.packge == sym)) {
4686 //not exported to this module:
4687 if (env.toplevel.modle != syms.unnamedModule) {
4688 return diags.fragment(Fragments.NotDefAccessNotExportedToModule(sym,
4689 sym.modle,
4690 env.toplevel.modle));
4691 } else {
4692 return diags.fragment(Fragments.NotDefAccessNotExportedToModuleFromUnnamed(sym,
4693 sym.modle));
4694 }
4695 } else {
4696 //not exported:
4697 if (env.toplevel.modle != syms.unnamedModule) {
4698 return diags.fragment(Fragments.NotDefAccessNotExported(sym,
4699 sym.modle));
4700 } else {
4701 return diags.fragment(Fragments.NotDefAccessNotExportedFromUnnamed(sym,
4702 sym.modle));
4703 }
4704 }
4705 }
4706 }
4707
4708 /**
4709 * InvalidSymbolError error class indicating that an instance member
4710 * has erroneously been accessed from a static context.
4711 */
4712 class StaticError extends InvalidSymbolError {
4713
4714 StaticError(Symbol sym) {
4715 this(sym, "static error");
4716 }
4717
4718 StaticError(Symbol sym, String debugName) {
4719 super(STATICERR, sym, debugName);
4720 }
4721
4722 @Override
4723 JCDiagnostic getDiagnostic(JCDiagnostic.DiagnosticType dkind,
4724 DiagnosticPosition pos,
4725 Symbol location,
4726 Type site,
4727 Name name,
4728 List<Type> argtypes,
4729 List<Type> typeargtypes) {
4730 Symbol errSym = ((sym.kind == TYP && sym.type.hasTag(CLASS))
4731 ? types.erasure(sym.type).tsym
4732 : sym);
4733 return diags.create(dkind, log.currentSource(), pos,
4734 "non-static.cant.be.ref", kindName(sym), errSym);
4735 }
4736 }
4737
4738 /**
4739 * Specialization of {@link InvalidSymbolError} for illegal
4740 * early accesses within a constructor prologue.
4741 */
4742 class RefBeforeCtorCalledError extends StaticError {
4743
4744 RefBeforeCtorCalledError(Symbol sym) {
4745 super(sym, "prologue error");
4746 }
4747
4748 @Override
4749 JCDiagnostic getDiagnostic(JCDiagnostic.DiagnosticType dkind,
4750 DiagnosticPosition pos,
4751 Symbol location,
4752 Type site,
4753 Name name,
4754 List<Type> argtypes,
4755 List<Type> typeargtypes) {
4756 Symbol errSym = ((sym.kind == TYP && sym.type.hasTag(CLASS))
4757 ? types.erasure(sym.type).tsym
4758 : sym);
4759 return diags.create(dkind, log.currentSource(), pos,
4760 "cant.ref.before.ctor.called", errSym);
4761 }
4762 }
4763
4764 /**
4765 * InvalidSymbolError error class indicating that a pair of symbols
4766 * (either methods, constructors or operands) are ambiguous
4767 * given an actual arguments/type argument list.
4768 */
4769 class AmbiguityError extends ResolveError {
4770
4771 /** The other maximally specific symbol */
4772 List<Symbol> ambiguousSyms = List.nil();
4773
4774 @Override
4775 public boolean exists() {
4776 return true;
4777 }
4778
4779 AmbiguityError(Symbol sym1, Symbol sym2) {
4780 super(AMBIGUOUS, "ambiguity error");
4781 ambiguousSyms = flatten(sym2).appendList(flatten(sym1));
4782 }
4783
4784 private List<Symbol> flatten(Symbol sym) {
4785 if (sym.kind == AMBIGUOUS) {
4786 return ((AmbiguityError)sym.baseSymbol()).ambiguousSyms;
4787 } else {
4788 return List.of(sym);
4789 }
4790 }
4791
4792 AmbiguityError addAmbiguousSymbol(Symbol s) {
4793 ambiguousSyms = ambiguousSyms.prepend(s);
4794 return this;
4795 }
4796
4797 @Override
4798 JCDiagnostic getDiagnostic(JCDiagnostic.DiagnosticType dkind,
4799 DiagnosticPosition pos,
4800 Symbol location,
4801 Type site,
4802 Name name,
4803 List<Type> argtypes,
4804 List<Type> typeargtypes) {
4805 List<Symbol> diagSyms = ambiguousSyms.reverse();
4806 Symbol s1 = diagSyms.head;
4807 Symbol s2 = diagSyms.tail.head;
4808 Name sname = s1.name;
4809 if (sname == names.init) sname = s1.owner.name;
4810 return diags.create(dkind, log.currentSource(),
4811 pos, "ref.ambiguous", sname,
4812 kindName(s1),
4813 s1,
4814 s1.location(site, types),
4815 kindName(s2),
4816 s2,
4817 s2.location(site, types));
4818 }
4819
4820 /**
4821 * If multiple applicable methods are found during overload and none of them
4822 * is more specific than the others, attempt to merge their signatures.
4823 */
4824 Symbol mergeAbstracts(Type site) {
4825 List<Symbol> ambiguousInOrder = ambiguousSyms.reverse();
4826 return types.mergeAbstracts(ambiguousInOrder, site, true).orElse(this);
4827 }
4828
4829 @Override
4830 protected Symbol access(Name name, TypeSymbol location) {
4831 Symbol firstAmbiguity = ambiguousSyms.last();
4832 return firstAmbiguity.kind == TYP ?
4833 types.createErrorType(name, location, firstAmbiguity.type).tsym :
4834 firstAmbiguity;
4835 }
4836 }
4837
4838 class BadVarargsMethod extends ResolveError {
4839
4840 ResolveError delegatedError;
4841
4842 BadVarargsMethod(ResolveError delegatedError) {
4843 super(delegatedError.kind, "badVarargs");
4844 this.delegatedError = delegatedError;
4845 }
4846
4847 @Override
4848 public Symbol baseSymbol() {
4849 return delegatedError.baseSymbol();
4850 }
4851
4852 @Override
4853 protected Symbol access(Name name, TypeSymbol location) {
4854 return delegatedError.access(name, location);
4855 }
4856
4857 @Override
4858 public boolean exists() {
4859 return true;
4860 }
4861
4862 @Override
4863 JCDiagnostic getDiagnostic(DiagnosticType dkind, DiagnosticPosition pos, Symbol location, Type site, Name name, List<Type> argtypes, List<Type> typeargtypes) {
4864 return delegatedError.getDiagnostic(dkind, pos, location, site, name, argtypes, typeargtypes);
4865 }
4866 }
4867
4868 /**
4869 * BadMethodReferenceError error class indicating that a method reference symbol has been found,
4870 * but with the wrong staticness.
4871 */
4872 class BadMethodReferenceError extends StaticError {
4873
4874 boolean unboundLookup;
4875
4876 public BadMethodReferenceError(Symbol sym, boolean unboundLookup) {
4877 super(sym, "bad method ref error");
4878 this.unboundLookup = unboundLookup;
4879 }
4880
4881 @Override
4882 JCDiagnostic getDiagnostic(DiagnosticType dkind, DiagnosticPosition pos, Symbol location, Type site, Name name, List<Type> argtypes, List<Type> typeargtypes) {
4883 final String key;
4884 if (!unboundLookup) {
4885 key = "bad.static.method.in.bound.lookup";
4886 } else if (sym.isStatic()) {
4887 key = "bad.static.method.in.unbound.lookup";
4888 } else {
4889 key = "bad.instance.method.in.unbound.lookup";
4890 }
4891 return sym.kind.isResolutionError() ?
4892 ((ResolveError)sym).getDiagnostic(dkind, pos, location, site, name, argtypes, typeargtypes) :
4893 diags.create(dkind, log.currentSource(), pos, key, Kinds.kindName(sym), sym);
4894 }
4895 }
4896
4897 /**
4898 * BadConstructorReferenceError error class indicating that a constructor reference symbol has been found,
4899 * but pointing to a class for which an enclosing instance is not available.
4900 */
4901 class BadConstructorReferenceError extends InvalidSymbolError {
4902
4903 public BadConstructorReferenceError(Symbol sym) {
4904 super(MISSING_ENCL, sym, "BadConstructorReferenceError");
4905 }
4906
4907 @Override
4908 JCDiagnostic getDiagnostic(DiagnosticType dkind, DiagnosticPosition pos, Symbol location, Type site, Name name, List<Type> argtypes, List<Type> typeargtypes) {
4909 return diags.create(dkind, log.currentSource(), pos,
4910 "cant.access.inner.cls.constr", site.tsym.name, argtypes, site.getEnclosingType());
4911 }
4912 }
4913
4914 class BadClassFileError extends InvalidSymbolError {
4915
4916 private final CompletionFailure ex;
4917
4918 public BadClassFileError(CompletionFailure ex) {
4919 super(HIDDEN, ex.sym, "BadClassFileError");
4920 this.name = sym.name;
4921 this.ex = ex;
4922 }
4923
4924 @Override
4925 JCDiagnostic getDiagnostic(DiagnosticType dkind, DiagnosticPosition pos, Symbol location, Type site, Name name, List<Type> argtypes, List<Type> typeargtypes) {
4926 JCDiagnostic d = diags.create(dkind, log.currentSource(), pos,
4927 "cant.access", ex.sym, ex.getDetailValue());
4928
4929 d.setFlag(DiagnosticFlag.NON_DEFERRABLE);
4930 return d;
4931 }
4932
4933 }
4934
4935 /**
4936 * Helper class for method resolution diagnostic simplification.
4937 * Certain resolution diagnostic are rewritten as simpler diagnostic
4938 * where the enclosing resolution diagnostic (i.e. 'inapplicable method')
4939 * is stripped away, as it doesn't carry additional info. The logic
4940 * for matching a given diagnostic is given in terms of a template
4941 * hierarchy: a diagnostic template can be specified programmatically,
4942 * so that only certain diagnostics are matched. Each templete is then
4943 * associated with a rewriter object that carries out the task of rewtiting
4944 * the diagnostic to a simpler one.
4945 */
4946 static class MethodResolutionDiagHelper {
4947
4948 /**
4949 * A diagnostic rewriter transforms a method resolution diagnostic
4950 * into a simpler one
4951 */
4952 interface DiagnosticRewriter {
4953 JCDiagnostic rewriteDiagnostic(JCDiagnostic.Factory diags,
4954 DiagnosticPosition preferredPos, DiagnosticSource preferredSource,
4955 DiagnosticType preferredKind, JCDiagnostic d);
4956 }
4957
4958 /**
4959 * A diagnostic template is made up of two ingredients: (i) a regular
4960 * expression for matching a diagnostic key and (ii) a list of sub-templates
4961 * for matching diagnostic arguments.
4962 */
4963 static class Template {
4964
4965 /** regex used to match diag key */
4966 String regex;
4967
4968 /** templates used to match diagnostic args */
4969 Template[] subTemplates;
4970
4971 Template(String key, Template... subTemplates) {
4972 this.regex = key;
4973 this.subTemplates = subTemplates;
4974 }
4975
4976 /**
4977 * Returns true if the regex matches the diagnostic key and if
4978 * all diagnostic arguments are matches by corresponding sub-templates.
4979 */
4980 boolean matches(Object o) {
4981 JCDiagnostic d = (JCDiagnostic)o;
4982 Object[] args = d.getArgs();
4983 if (!d.getCode().matches(regex) ||
4984 subTemplates.length != d.getArgs().length) {
4985 return false;
4986 }
4987 for (int i = 0; i < args.length ; i++) {
4988 if (!subTemplates[i].matches(args[i])) {
4989 return false;
4990 }
4991 }
4992 return true;
4993 }
4994 }
4995
4996 /**
4997 * Common rewriter for all argument mismatch simplifications.
4998 */
4999 static class ArgMismatchRewriter implements DiagnosticRewriter {
5000
5001 /** the index of the subdiagnostic to be used as primary. */
5002 int causeIndex;
5003
5004 public ArgMismatchRewriter(int causeIndex) {
5005 this.causeIndex = causeIndex;
5006 }
5007
5008 @Override
5009 public JCDiagnostic rewriteDiagnostic(JCDiagnostic.Factory diags,
5010 DiagnosticPosition preferredPos, DiagnosticSource preferredSource,
5011 DiagnosticType preferredKind, JCDiagnostic d) {
5012 JCDiagnostic cause = (JCDiagnostic)d.getArgs()[causeIndex];
5013 DiagnosticPosition pos = d.getDiagnosticPosition();
5014 if (pos == null) {
5015 pos = preferredPos;
5016 }
5017 return diags.create(preferredKind, preferredSource, pos,
5018 "prob.found.req", cause);
5019 }
5020 }
5021
5022 /** a dummy template that match any diagnostic argument */
5023 static final Template skip = new Template("") {
5024 @Override
5025 boolean matches(Object d) {
5026 return true;
5027 }
5028 };
5029
5030 /** template for matching inference-free arguments mismatch failures */
5031 static final Template argMismatchTemplate = new Template(MethodCheckDiag.ARG_MISMATCH.regex(), skip);
5032
5033 /** template for matching inference related arguments mismatch failures */
5034 static final Template inferArgMismatchTemplate = new Template(MethodCheckDiag.ARG_MISMATCH.regex(), skip, skip) {
5035 @Override
5036 boolean matches(Object o) {
5037 if (!super.matches(o)) {
5038 return false;
5039 }
5040 JCDiagnostic d = (JCDiagnostic)o;
5041 @SuppressWarnings("unchecked")
5042 List<Type> tvars = (List<Type>)d.getArgs()[0];
5043 return !containsAny(d, tvars);
5044 }
5045
5046 BiPredicate<Object, List<Type>> containsPredicate = (o, ts) -> {
5047 if (o instanceof Type type) {
5048 return type.containsAny(ts);
5049 } else if (o instanceof JCDiagnostic diagnostic) {
5050 return containsAny(diagnostic, ts);
5051 } else {
5052 return false;
5053 }
5054 };
5055
5056 boolean containsAny(JCDiagnostic d, List<Type> ts) {
5057 return Stream.of(d.getArgs())
5058 .anyMatch(o -> containsPredicate.test(o, ts));
5059 }
5060 };
5061
5062 /** rewriter map used for method resolution simplification */
5063 static final Map<Template, DiagnosticRewriter> rewriters = new LinkedHashMap<>();
5064
5065 static {
5066 rewriters.put(argMismatchTemplate, new ArgMismatchRewriter(0));
5067 rewriters.put(inferArgMismatchTemplate, new ArgMismatchRewriter(1));
5068 }
5069
5070 /**
5071 * Main entry point for diagnostic rewriting - given a diagnostic, see if any templates matches it,
5072 * and rewrite it accordingly.
5073 */
5074 static JCDiagnostic rewrite(JCDiagnostic.Factory diags, DiagnosticPosition pos, DiagnosticSource source,
5075 DiagnosticType dkind, JCDiagnostic d) {
5076 for (Map.Entry<Template, DiagnosticRewriter> _entry : rewriters.entrySet()) {
5077 if (_entry.getKey().matches(d)) {
5078 JCDiagnostic simpleDiag =
5079 _entry.getValue().rewriteDiagnostic(diags, pos, source, dkind, d);
5080 simpleDiag.setFlag(DiagnosticFlag.COMPRESSED);
5081 return simpleDiag;
5082 }
5083 }
5084 return null;
5085 }
5086 }
5087
5088 enum MethodResolutionPhase {
5089 BASIC(false, false),
5090 BOX(true, false),
5091 VARARITY(true, true) {
5092 @Override
5093 public Symbol mergeResults(Symbol bestSoFar, Symbol sym) {
5094 //Check invariants (see {@code LookupHelper.shouldStop})
5095 Assert.check(bestSoFar.kind.isResolutionError() && bestSoFar.kind != AMBIGUOUS);
5096 if (!sym.kind.isResolutionError()) {
5097 //varargs resolution successful
5098 return sym;
5099 } else {
5100 //pick best error
5101 switch (bestSoFar.kind) {
5102 case WRONG_MTH:
5103 case WRONG_MTHS:
5104 //Override previous errors if they were caused by argument mismatch.
5105 //This generally means preferring current symbols - but we need to pay
5106 //attention to the fact that the varargs lookup returns 'less' candidates
5107 //than the previous rounds, and adjust that accordingly.
5108 switch (sym.kind) {
5109 case WRONG_MTH:
5110 //if the previous round matched more than one method, return that
5111 //result instead
5112 return bestSoFar.kind == WRONG_MTHS ?
5113 bestSoFar : sym;
5114 case ABSENT_MTH:
5115 //do not override erroneous symbol if the arity lookup did not
5116 //match any method
5117 return bestSoFar;
5118 case WRONG_MTHS:
5119 default:
5120 //safe to override
5121 return sym;
5122 }
5123 default:
5124 //otherwise, return first error
5125 return bestSoFar;
5126 }
5127 }
5128 }
5129 };
5130
5131 final boolean isBoxingRequired;
5132 final boolean isVarargsRequired;
5133
5134 MethodResolutionPhase(boolean isBoxingRequired, boolean isVarargsRequired) {
5135 this.isBoxingRequired = isBoxingRequired;
5136 this.isVarargsRequired = isVarargsRequired;
5137 }
5138
5139 public boolean isBoxingRequired() {
5140 return isBoxingRequired;
5141 }
5142
5143 public boolean isVarargsRequired() {
5144 return isVarargsRequired;
5145 }
5146
5147 public Symbol mergeResults(Symbol prev, Symbol sym) {
5148 return sym;
5149 }
5150 }
5151
5152 final List<MethodResolutionPhase> methodResolutionSteps = List.of(BASIC, BOX, VARARITY);
5153
5154 /**
5155 * A resolution context is used to keep track of intermediate results of
5156 * overload resolution, such as list of method that are not applicable
5157 * (used to generate more precise diagnostics) and so on. Resolution contexts
5158 * can be nested - this means that when each overload resolution routine should
5159 * work within the resolution context it created.
5160 */
5161 class MethodResolutionContext {
5162
5163 private List<Candidate> candidates = List.nil();
5164
5165 MethodResolutionPhase step = null;
5166
5167 MethodCheck methodCheck = resolveMethodCheck;
5168
5169 private boolean internalResolution = false;
5170 private DeferredAttr.AttrMode attrMode = DeferredAttr.AttrMode.SPECULATIVE;
5171
5172 void addInapplicableCandidate(Symbol sym, JCDiagnostic details) {
5173 Candidate c = new Candidate(currentResolutionContext.step, sym, details, null);
5174 candidates = candidates.append(c);
5175 }
5176
5177 void addApplicableCandidate(Symbol sym, Type mtype) {
5178 Candidate c = new Candidate(currentResolutionContext.step, sym, null, mtype);
5179 candidates = candidates.append(c);
5180 }
5181
5182 DeferredAttrContext deferredAttrContext(Symbol sym, InferenceContext inferenceContext, ResultInfo pendingResult, Warner warn) {
5183 DeferredAttrContext parent = (pendingResult == null)
5184 ? deferredAttr.emptyDeferredAttrContext
5185 : pendingResult.checkContext.deferredAttrContext();
5186 return deferredAttr.new DeferredAttrContext(attrMode, sym, step,
5187 inferenceContext, parent, warn);
5188 }
5189
5190 /**
5191 * This class represents an overload resolution candidate. There are two
5192 * kinds of candidates: applicable methods and inapplicable methods;
5193 * applicable methods have a pointer to the instantiated method type,
5194 * while inapplicable candidates contain further details about the
5195 * reason why the method has been considered inapplicable.
5196 */
5197 @SuppressWarnings("overrides")
5198 class Candidate {
5199
5200 final MethodResolutionPhase step;
5201 final Symbol sym;
5202 final JCDiagnostic details;
5203 final Type mtype;
5204
5205 private Candidate(MethodResolutionPhase step, Symbol sym, JCDiagnostic details, Type mtype) {
5206 this.step = step;
5207 this.sym = sym;
5208 this.details = details;
5209 this.mtype = mtype;
5210 }
5211
5212 boolean isApplicable() {
5213 return mtype != null;
5214 }
5215 }
5216
5217 DeferredAttr.AttrMode attrMode() {
5218 return attrMode;
5219 }
5220 }
5221
5222 MethodResolutionContext currentResolutionContext = null;
5223 }