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 if (bestSoFar.kind == AMBIGUOUS) {
1865 AmbiguityError a_err = (AmbiguityError)bestSoFar.baseSymbol();
1866 bestSoFar = a_err.mergeAbstracts(site);
1867 }
1868 return bestSoFar;
1869 }
1870 // where
1871 private Symbol findMethod(Env<AttrContext> env,
1872 Type site,
1873 Name name,
1874 List<Type> argtypes,
1875 List<Type> typeargtypes,
1876 Type intype,
1877 Symbol bestSoFar,
1878 boolean allowBoxing,
1879 boolean useVarargs) {
1880 @SuppressWarnings({"unchecked","rawtypes"})
1881 List<Type>[] itypes = (List<Type>[])new List[] { List.<Type>nil(), List.<Type>nil() };
1882
1883 InterfaceLookupPhase iphase = InterfaceLookupPhase.ABSTRACT_OK;
1884 boolean isInterface = site.tsym.isInterface();
1885 for (TypeSymbol s : isInterface ? List.of(intype.tsym) : superclasses(intype)) {
1886 bestSoFar = findMethodInScope(env, site, name, argtypes, typeargtypes,
1887 s.members(), bestSoFar, allowBoxing, useVarargs, true);
1888 if (name == names.init) return bestSoFar;
1889 iphase = (iphase == null) ? null : iphase.update(s, this);
1890 if (iphase != null) {
1891 for (Type itype : types.interfaces(s.type)) {
1892 itypes[iphase.ordinal()] = types.union(types.closure(itype), itypes[iphase.ordinal()]);
1893 }
1894 }
1895 }
1896
1897 Symbol concrete = bestSoFar.kind.isValid() &&
1898 (bestSoFar.flags() & ABSTRACT) == 0 ?
1899 bestSoFar : methodNotFound;
1900
1901 for (InterfaceLookupPhase iphase2 : InterfaceLookupPhase.values()) {
1902 //keep searching for abstract methods
1903 for (Type itype : itypes[iphase2.ordinal()]) {
1904 if (!itype.isInterface()) continue; //skip j.l.Object (included by Types.closure())
1905 if (iphase2 == InterfaceLookupPhase.DEFAULT_OK &&
1906 (itype.tsym.flags() & DEFAULT) == 0) continue;
1907 bestSoFar = findMethodInScope(env, site, name, argtypes, typeargtypes,
1908 itype.tsym.members(), bestSoFar, allowBoxing, useVarargs, true);
1909 if (concrete != bestSoFar &&
1910 concrete.kind.isValid() &&
1911 bestSoFar.kind.isValid() &&
1912 types.isSubSignature(concrete.type, bestSoFar.type)) {
1913 //this is an hack - as javac does not do full membership checks
1914 //most specific ends up comparing abstract methods that might have
1915 //been implemented by some concrete method in a subclass and,
1916 //because of raw override, it is possible for an abstract method
1917 //to be more specific than the concrete method - so we need
1918 //to explicitly call that out (see CR 6178365)
1919 bestSoFar = concrete;
1920 }
1921 }
1922 }
1923 if (isInterface && bestSoFar.kind.isResolutionError()) {
1924 bestSoFar = findMethodInScope(env, site, name, argtypes, typeargtypes,
1925 syms.objectType.tsym.members(), bestSoFar, allowBoxing, useVarargs, true);
1926 if (bestSoFar.kind.isValid()) {
1927 Symbol baseSymbol = bestSoFar;
1928 bestSoFar = new MethodSymbol(bestSoFar.flags_field, bestSoFar.name, bestSoFar.type, intype.tsym) {
1929 @Override
1930 public Symbol baseSymbol() {
1931 return baseSymbol;
1932 }
1933 };
1934 }
1935 }
1936 return bestSoFar;
1937 }
1938
1939 enum InterfaceLookupPhase {
1940 ABSTRACT_OK() {
1941 @Override
1942 InterfaceLookupPhase update(Symbol s, Resolve rs) {
1943 //We should not look for abstract methods if receiver is a concrete class
1944 //(as concrete classes are expected to implement all abstracts coming
1945 //from superinterfaces)
1946 if ((s.flags() & (ABSTRACT | INTERFACE | ENUM)) != 0) {
1947 return this;
1948 } else {
1949 return DEFAULT_OK;
1950 }
1951 }
1952 },
1953 DEFAULT_OK() {
1954 @Override
1955 InterfaceLookupPhase update(Symbol s, Resolve rs) {
1956 return this;
1957 }
1958 };
1959
1960 abstract InterfaceLookupPhase update(Symbol s, Resolve rs);
1961 }
1962
1963 /**
1964 * Return an Iterable object to scan the superclasses of a given type.
1965 * It's crucial that the scan is done lazily, as we don't want to accidentally
1966 * access more supertypes than strictly needed (as this could trigger completion
1967 * errors if some of the not-needed supertypes are missing/ill-formed).
1968 */
1969 Iterable<TypeSymbol> superclasses(final Type intype) {
1970 return () -> new Iterator<TypeSymbol>() {
1971
1972 List<TypeSymbol> seen = List.nil();
1973 TypeSymbol currentSym = symbolFor(intype);
1974 TypeSymbol prevSym = null;
1975
1976 public boolean hasNext() {
1977 if (currentSym == syms.noSymbol) {
1978 currentSym = symbolFor(types.supertype(prevSym.type));
1979 }
1980 return currentSym != null;
1981 }
1982
1983 public TypeSymbol next() {
1984 prevSym = currentSym;
1985 currentSym = syms.noSymbol;
1986 Assert.check(prevSym != null || prevSym != syms.noSymbol);
1987 return prevSym;
1988 }
1989
1990 public void remove() {
1991 throw new UnsupportedOperationException();
1992 }
1993
1994 TypeSymbol symbolFor(Type t) {
1995 if (!t.hasTag(CLASS) &&
1996 !t.hasTag(TYPEVAR)) {
1997 return null;
1998 }
1999 t = types.skipTypeVars(t, false);
2000 if (seen.contains(t.tsym)) {
2001 //degenerate case in which we have a circular
2002 //class hierarchy - because of ill-formed classfiles
2003 return null;
2004 }
2005 seen = seen.prepend(t.tsym);
2006 return t.tsym;
2007 }
2008 };
2009 }
2010
2011 /** Find unqualified method matching given name, type and value arguments.
2012 * @param env The current environment.
2013 * @param name The method's name.
2014 * @param argtypes The method's value arguments.
2015 * @param typeargtypes The method's type arguments.
2016 * @param allowBoxing Allow boxing conversions of arguments.
2017 * @param useVarargs Box trailing arguments into an array for varargs.
2018 */
2019 Symbol findFun(Env<AttrContext> env, Name name,
2020 List<Type> argtypes, List<Type> typeargtypes,
2021 boolean allowBoxing, boolean useVarargs) {
2022 Symbol bestSoFar = methodNotFound;
2023 Env<AttrContext> env1 = env;
2024 boolean staticOnly = false;
2025 while (env1.outer != null) {
2026 if (isStatic(env1)) staticOnly = true;
2027 Assert.check(env1.info.preferredTreeForDiagnostics == null);
2028 env1.info.preferredTreeForDiagnostics = env.tree;
2029 try {
2030 Symbol sym = findMethod(
2031 env1, env1.enclClass.sym.type, name, argtypes, typeargtypes,
2032 allowBoxing, useVarargs);
2033 if (sym.exists()) {
2034 if (sym.kind == MTH &&
2035 sym.owner.kind == TYP &&
2036 (sym.flags() & STATIC) == 0) {
2037 if (staticOnly)
2038 return new StaticError(sym);
2039 if (env1.info.ctorPrologue && env1 == env)
2040 return new RefBeforeCtorCalledError(sym);
2041 }
2042 return sym;
2043 } else {
2044 bestSoFar = bestOf(bestSoFar, sym);
2045 }
2046 } finally {
2047 env1.info.preferredTreeForDiagnostics = null;
2048 }
2049 if ((env1.enclClass.sym.flags() & STATIC) != 0) staticOnly = true;
2050 env1 = env1.outer;
2051 }
2052
2053 Symbol sym = findMethod(env, syms.predefClass.type, name, argtypes,
2054 typeargtypes, allowBoxing, useVarargs);
2055 if (sym.exists())
2056 return sym;
2057
2058 for (Symbol currentSym : env.toplevel.namedImportScope.getSymbolsByName(name)) {
2059 Symbol origin = env.toplevel.namedImportScope.getOrigin(currentSym).owner;
2060 if (currentSym.kind == MTH) {
2061 if (currentSym.owner.type != origin.type)
2062 currentSym = currentSym.clone(origin);
2063 if (!isAccessible(env, origin.type, currentSym))
2064 currentSym = new AccessError(env, origin.type, currentSym);
2065 bestSoFar = selectBest(env, origin.type,
2066 argtypes, typeargtypes,
2067 currentSym, bestSoFar,
2068 allowBoxing, useVarargs);
2069 }
2070 }
2071 if (bestSoFar.exists())
2072 return bestSoFar;
2073
2074 for (Symbol currentSym : env.toplevel.starImportScope.getSymbolsByName(name)) {
2075 Symbol origin = env.toplevel.starImportScope.getOrigin(currentSym).owner;
2076 if (currentSym.kind == MTH) {
2077 if (currentSym.owner.type != origin.type)
2078 currentSym = currentSym.clone(origin);
2079 if (!isAccessible(env, origin.type, currentSym))
2080 currentSym = new AccessError(env, origin.type, currentSym);
2081 bestSoFar = selectBest(env, origin.type,
2082 argtypes, typeargtypes,
2083 currentSym, bestSoFar,
2084 allowBoxing, useVarargs);
2085 }
2086 }
2087 return bestSoFar;
2088 }
2089
2090 /** Load toplevel or member class with given fully qualified name and
2091 * verify that it is accessible.
2092 * @param env The current environment.
2093 * @param name The fully qualified name of the class to be loaded.
2094 */
2095 Symbol loadClass(Env<AttrContext> env, Name name, RecoveryLoadClass recoveryLoadClass) {
2096 try {
2097 ClassSymbol c = finder.loadClass(env.toplevel.modle, name);
2098 return isAccessible(env, c) ? c : new AccessError(env, null, c);
2099 } catch (ClassFinder.BadClassFile err) {
2100 return new BadClassFileError(err);
2101 } catch (CompletionFailure ex) {
2102 Symbol candidate = recoveryLoadClass.loadClass(env, name);
2103
2104 if (candidate != null) {
2105 return candidate;
2106 }
2107
2108 return typeNotFound;
2109 }
2110 }
2111
2112 public interface RecoveryLoadClass {
2113 Symbol loadClass(Env<AttrContext> env, Name name);
2114 }
2115
2116 private final RecoveryLoadClass noRecovery = (env, name) -> null;
2117
2118 private final RecoveryLoadClass doRecoveryLoadClass = new RecoveryLoadClass() {
2119 @Override public Symbol loadClass(Env<AttrContext> env, Name name) {
2120 List<Name> candidates = Convert.classCandidates(name);
2121 return lookupInvisibleSymbol(env, name,
2122 n -> () -> createCompoundIterator(candidates,
2123 c -> syms.getClassesForName(c)
2124 .iterator()),
2125 (ms, n) -> {
2126 for (Name candidate : candidates) {
2127 try {
2128 return finder.loadClass(ms, candidate);
2129 } catch (CompletionFailure cf) {
2130 //ignore
2131 }
2132 }
2133 return null;
2134 }, sym -> sym.kind == Kind.TYP, typeNotFound);
2135 }
2136 };
2137
2138 private final RecoveryLoadClass namedImportScopeRecovery = (env, name) -> {
2139 Scope importScope = env.toplevel.namedImportScope;
2140 Symbol existing = importScope.findFirst(Convert.shortName(name),
2141 sym -> sym.kind == TYP && sym.flatName() == name);
2142
2143 if (existing != null) {
2144 return new InvisibleSymbolError(env, true, existing);
2145 }
2146 return null;
2147 };
2148
2149 private final RecoveryLoadClass starImportScopeRecovery = (env, name) -> {
2150 Scope importScope = env.toplevel.starImportScope;
2151 Symbol existing = importScope.findFirst(Convert.shortName(name),
2152 sym -> sym.kind == TYP && sym.flatName() == name);
2153
2154 if (existing != null) {
2155 try {
2156 existing = finder.loadClass(existing.packge().modle, name);
2157
2158 return new InvisibleSymbolError(env, true, existing);
2159 } catch (CompletionFailure cf) {
2160 //ignore
2161 }
2162 }
2163
2164 return null;
2165 };
2166
2167 Symbol lookupPackage(Env<AttrContext> env, Name name) {
2168 PackageSymbol pack = syms.lookupPackage(env.toplevel.modle, name);
2169
2170 if (allowModules && isImportOnDemand(env, name)) {
2171 if (pack.members().isEmpty()) {
2172 return lookupInvisibleSymbol(env, name, syms::getPackagesForName, syms::enterPackage, sym -> {
2173 sym.complete();
2174 return !sym.members().isEmpty();
2175 }, pack);
2176 }
2177 }
2178
2179 return pack;
2180 }
2181
2182 private boolean isImportOnDemand(Env<AttrContext> env, Name name) {
2183 if (!env.tree.hasTag(IMPORT))
2184 return false;
2185
2186 JCTree qualid = ((JCImport) env.tree).qualid;
2187
2188 if (!qualid.hasTag(SELECT))
2189 return false;
2190
2191 if (TreeInfo.name(qualid) != names.asterisk)
2192 return false;
2193
2194 return TreeInfo.fullName(((JCFieldAccess) qualid).selected) == name;
2195 }
2196
2197 private <S extends Symbol> Symbol lookupInvisibleSymbol(Env<AttrContext> env,
2198 Name name,
2199 Function<Name, Iterable<S>> get,
2200 BiFunction<ModuleSymbol, Name, S> load,
2201 Predicate<S> validate,
2202 Symbol defaultResult) {
2203 //even if a class/package cannot be found in the current module and among packages in modules
2204 //it depends on that are exported for any or this module, the class/package may exist internally
2205 //in some of these modules, or may exist in a module on which this module does not depend.
2206 //Provide better diagnostic in such cases by looking for the class in any module:
2207 Iterable<? extends S> candidates = get.apply(name);
2208
2209 for (S sym : candidates) {
2210 if (validate.test(sym))
2211 return createInvisibleSymbolError(env, sym);
2212 }
2213
2214 Set<ModuleSymbol> recoverableModules = new HashSet<>(syms.getAllModules());
2215
2216 recoverableModules.add(syms.unnamedModule);
2217 recoverableModules.remove(env.toplevel.modle);
2218
2219 for (ModuleSymbol ms : recoverableModules) {
2220 //avoid overly eager completing classes from source-based modules, as those
2221 //may not be completable with the current compiler settings:
2222 if (ms.sourceLocation == null) {
2223 if (ms.classLocation == null) {
2224 ms = moduleFinder.findModule(ms);
2225 }
2226
2227 if (ms.kind != ERR) {
2228 S sym = load.apply(ms, name);
2229
2230 if (sym != null && validate.test(sym)) {
2231 return createInvisibleSymbolError(env, sym);
2232 }
2233 }
2234 }
2235 }
2236
2237 return defaultResult;
2238 }
2239
2240 private Symbol createInvisibleSymbolError(Env<AttrContext> env, Symbol sym) {
2241 if (symbolPackageVisible(env, sym)) {
2242 return new AccessError(env, null, sym);
2243 } else {
2244 return new InvisibleSymbolError(env, false, sym);
2245 }
2246 }
2247
2248 private boolean symbolPackageVisible(Env<AttrContext> env, Symbol sym) {
2249 ModuleSymbol envMod = env.toplevel.modle;
2250 PackageSymbol symPack = sym.packge();
2251 return envMod == symPack.modle ||
2252 envMod.visiblePackages.containsKey(symPack.fullname);
2253 }
2254
2255 /**
2256 * Find a type declared in a scope (not inherited). Return null
2257 * if none is found.
2258 * @param env The current environment.
2259 * @param site The original type from where the selection takes
2260 * place.
2261 * @param name The type's name.
2262 * @param c The class to search for the member type. This is
2263 * always a superclass or implemented interface of
2264 * site's class.
2265 */
2266 Symbol findImmediateMemberType(Env<AttrContext> env,
2267 Type site,
2268 Name name,
2269 TypeSymbol c) {
2270 for (Symbol sym : c.members().getSymbolsByName(name)) {
2271 if (sym.kind == TYP) {
2272 return isAccessible(env, site, sym)
2273 ? sym
2274 : new AccessError(env, site, sym);
2275 }
2276 }
2277 return typeNotFound;
2278 }
2279
2280 /** Find a member type inherited from a superclass or interface.
2281 * @param env The current environment.
2282 * @param site The original type from where the selection takes
2283 * place.
2284 * @param name The type's name.
2285 * @param c The class to search for the member type. This is
2286 * always a superclass or implemented interface of
2287 * site's class.
2288 */
2289 Symbol findInheritedMemberType(Env<AttrContext> env,
2290 Type site,
2291 Name name,
2292 TypeSymbol c) {
2293 Symbol bestSoFar = typeNotFound;
2294 Symbol sym;
2295 Type st = types.supertype(c.type);
2296 if (st != null && st.hasTag(CLASS)) {
2297 sym = findMemberType(env, site, name, st.tsym);
2298 bestSoFar = bestOf(bestSoFar, sym);
2299 }
2300 for (List<Type> l = types.interfaces(c.type);
2301 bestSoFar.kind != AMBIGUOUS && l.nonEmpty();
2302 l = l.tail) {
2303 sym = findMemberType(env, site, name, l.head.tsym);
2304 if (!bestSoFar.kind.isResolutionError() &&
2305 !sym.kind.isResolutionError() &&
2306 sym.owner != bestSoFar.owner)
2307 bestSoFar = new AmbiguityError(bestSoFar, sym);
2308 else
2309 bestSoFar = bestOf(bestSoFar, sym);
2310 }
2311 return bestSoFar;
2312 }
2313
2314 /** Find qualified member type.
2315 * @param env The current environment.
2316 * @param site The original type from where the selection takes
2317 * place.
2318 * @param name The type's name.
2319 * @param c The class to search for the member type. This is
2320 * always a superclass or implemented interface of
2321 * site's class.
2322 */
2323 Symbol findMemberType(Env<AttrContext> env,
2324 Type site,
2325 Name name,
2326 TypeSymbol c) {
2327 Symbol sym = findImmediateMemberType(env, site, name, c);
2328
2329 if (sym != typeNotFound)
2330 return sym;
2331
2332 return findInheritedMemberType(env, site, name, c);
2333
2334 }
2335
2336 /** Find a global type in given scope and load corresponding class.
2337 * @param env The current environment.
2338 * @param scope The scope in which to look for the type.
2339 * @param name The type's name.
2340 */
2341 Symbol findGlobalType(Env<AttrContext> env, Scope scope, Name name, RecoveryLoadClass recoveryLoadClass) {
2342 Symbol bestSoFar = typeNotFound;
2343 for (Symbol s : scope.getSymbolsByName(name)) {
2344 Symbol sym = loadClass(env, s.flatName(), recoveryLoadClass);
2345 if (bestSoFar.kind == TYP && sym.kind == TYP &&
2346 bestSoFar != sym)
2347 return new AmbiguityError(bestSoFar, sym);
2348 else
2349 bestSoFar = bestOf(bestSoFar, sym);
2350 }
2351 return bestSoFar;
2352 }
2353
2354 Symbol findTypeVar(Env<AttrContext> env, Name name, boolean staticOnly) {
2355 for (Symbol sym : env.info.scope.getSymbolsByName(name)) {
2356 if (sym.kind == TYP) {
2357 if (sym.type.hasTag(TYPEVAR) &&
2358 (staticOnly || (isStatic(env) && sym.owner.kind == TYP)))
2359 // if staticOnly is set, it means that we have recursed through a static declaration,
2360 // so type variable symbols should not be accessible. If staticOnly is unset, but
2361 // we are in a static declaration (field or method), we should not allow type-variables
2362 // defined in the enclosing class to "leak" into this context.
2363 return new StaticError(sym);
2364 return sym;
2365 }
2366 }
2367 return typeNotFound;
2368 }
2369
2370 /** Find an unqualified type symbol.
2371 * @param env The current environment.
2372 * @param name The type's name.
2373 */
2374 Symbol findType(Env<AttrContext> env, Name name) {
2375 if (name == names.empty)
2376 return typeNotFound; // do not allow inadvertent "lookup" of anonymous types
2377 Symbol bestSoFar = typeNotFound;
2378 Symbol sym;
2379 boolean staticOnly = false;
2380 for (Env<AttrContext> env1 = env; env1.outer != null; env1 = env1.outer) {
2381 // First, look for a type variable and the first member type
2382 final Symbol tyvar = findTypeVar(env1, name, staticOnly);
2383 if (isStatic(env1)) staticOnly = true;
2384 sym = findImmediateMemberType(env1, env1.enclClass.sym.type,
2385 name, env1.enclClass.sym);
2386
2387 // Return the type variable if we have it, and have no
2388 // immediate member, OR the type variable is for a method.
2389 if (tyvar != typeNotFound) {
2390 if (env.baseClause || sym == typeNotFound ||
2391 (tyvar.kind == TYP && tyvar.exists() &&
2392 tyvar.owner.kind == MTH)) {
2393 return tyvar;
2394 }
2395 }
2396
2397 // If the environment is a class def, finish up,
2398 // otherwise, do the entire findMemberType
2399 if (sym == typeNotFound)
2400 sym = findInheritedMemberType(env1, env1.enclClass.sym.type,
2401 name, env1.enclClass.sym);
2402
2403 if (staticOnly && sym.kind == TYP &&
2404 sym.type.hasTag(CLASS) &&
2405 sym.type.getEnclosingType().hasTag(CLASS) &&
2406 env1.enclClass.sym.type.isParameterized() &&
2407 sym.type.getEnclosingType().isParameterized())
2408 return new StaticError(sym);
2409 else if (sym.exists()) return sym;
2410 else bestSoFar = bestOf(bestSoFar, sym);
2411
2412 JCClassDecl encl = env1.baseClause ? (JCClassDecl)env1.tree : env1.enclClass;
2413 if ((encl.sym.flags() & STATIC) != 0)
2414 staticOnly = true;
2415 }
2416
2417 if (!env.tree.hasTag(IMPORT)) {
2418 sym = findGlobalType(env, env.toplevel.namedImportScope, name, namedImportScopeRecovery);
2419 if (sym.exists()) return sym;
2420 else bestSoFar = bestOf(bestSoFar, sym);
2421
2422 sym = findGlobalType(env, env.toplevel.toplevelScope, name, noRecovery);
2423 if (sym.exists()) return sym;
2424 else bestSoFar = bestOf(bestSoFar, sym);
2425
2426 sym = findGlobalType(env, env.toplevel.packge.members(), name, noRecovery);
2427 if (sym.exists()) return sym;
2428 else bestSoFar = bestOf(bestSoFar, sym);
2429
2430 sym = findGlobalType(env, env.toplevel.starImportScope, name, starImportScopeRecovery);
2431 if (sym.exists()) return sym;
2432 else bestSoFar = bestOf(bestSoFar, sym);
2433 }
2434
2435 return bestSoFar;
2436 }
2437
2438 /** Find an unqualified identifier which matches a specified kind set.
2439 * @param pos position on which report warnings, if any;
2440 * null warnings should not be reported
2441 * @param env The current environment.
2442 * @param name The identifier's name.
2443 * @param kind Indicates the possible symbol kinds
2444 * (a subset of VAL, TYP, PCK).
2445 */
2446 Symbol findIdent(DiagnosticPosition pos, Env<AttrContext> env, Name name, KindSelector kind) {
2447 try {
2448 return checkNonExistentType(checkRestrictedType(pos, findIdentInternal(pos, env, name, kind), name));
2449 } catch (ClassFinder.BadClassFile err) {
2450 return new BadClassFileError(err);
2451 } catch (CompletionFailure cf) {
2452 chk.completionError(pos, cf);
2453 return typeNotFound;
2454 }
2455 }
2456
2457 Symbol findIdentInternal(DiagnosticPosition pos, Env<AttrContext> env, Name name, KindSelector kind) {
2458 Symbol bestSoFar = typeNotFound;
2459 Symbol sym;
2460
2461 if (kind.contains(KindSelector.VAL)) {
2462 sym = findVar(pos, env, name);
2463 if (sym.exists()) return sym;
2464 else bestSoFar = bestOf(bestSoFar, sym);
2465 }
2466
2467 if (kind.contains(KindSelector.TYP)) {
2468 sym = findType(env, name);
2469 if (sym.exists()) return sym;
2470 else bestSoFar = bestOf(bestSoFar, sym);
2471 }
2472
2473 if (kind.contains(KindSelector.PCK))
2474 return lookupPackage(env, name);
2475 else return bestSoFar;
2476 }
2477
2478 /** Find an identifier in a package which matches a specified kind set.
2479 * @param pos position on which report warnings, if any;
2480 * null warnings should not be reported
2481 * @param env The current environment.
2482 * @param name The identifier's name.
2483 * @param kind Indicates the possible symbol kinds
2484 * (a nonempty subset of TYP, PCK).
2485 */
2486 Symbol findIdentInPackage(DiagnosticPosition pos,
2487 Env<AttrContext> env, TypeSymbol pck,
2488 Name name, KindSelector kind) {
2489 return checkNonExistentType(checkRestrictedType(pos, findIdentInPackageInternal(env, pck, name, kind), name));
2490 }
2491
2492 Symbol findIdentInPackageInternal(Env<AttrContext> env, TypeSymbol pck,
2493 Name name, KindSelector kind) {
2494 Name fullname = TypeSymbol.formFullName(name, pck);
2495 Symbol bestSoFar = typeNotFound;
2496 if (kind.contains(KindSelector.TYP)) {
2497 RecoveryLoadClass recoveryLoadClass =
2498 allowModules && !kind.contains(KindSelector.PCK) &&
2499 !pck.exists() && !env.info.attributionMode.isSpeculative ?
2500 doRecoveryLoadClass : noRecovery;
2501 Symbol sym = loadClass(env, fullname, recoveryLoadClass);
2502 if (sym.exists()) {
2503 // don't allow programs to use flatnames
2504 if (name == sym.name) return sym;
2505 }
2506 else bestSoFar = bestOf(bestSoFar, sym);
2507 }
2508 if (kind.contains(KindSelector.PCK)) {
2509 return lookupPackage(env, fullname);
2510 }
2511 return bestSoFar;
2512 }
2513
2514 /** Find an identifier among the members of a given type `site'.
2515 * @param pos position on which report warnings, if any;
2516 * null warnings should not be reported
2517 * @param env The current environment.
2518 * @param site The type containing the symbol to be found.
2519 * @param name The identifier's name.
2520 * @param kind Indicates the possible symbol kinds
2521 * (a subset of VAL, TYP).
2522 */
2523 Symbol findIdentInType(DiagnosticPosition pos,
2524 Env<AttrContext> env, Type site,
2525 Name name, KindSelector kind) {
2526 try {
2527 return checkNonExistentType(checkRestrictedType(pos, findIdentInTypeInternal(env, site, name, kind), name));
2528 } catch (ClassFinder.BadClassFile err) {
2529 return new BadClassFileError(err);
2530 } catch (CompletionFailure cf) {
2531 chk.completionError(pos, cf);
2532 return typeNotFound;
2533 }
2534 }
2535
2536 private Symbol checkNonExistentType(Symbol symbol) {
2537 /* Guard against returning a type is not on the class path of the current compilation,
2538 * but *was* on the class path of a separate compilation that produced a class file
2539 * that is on the class path of the current compilation. Such a type will fail completion
2540 * but the completion failure may have been silently swallowed (e.g. missing annotation types)
2541 * with an error stub symbol lingering in the symbol tables.
2542 */
2543 return symbol instanceof ClassSymbol c && c.type.isErroneous() && c.classfile == null ? typeNotFound : symbol;
2544 }
2545
2546 Symbol findIdentInTypeInternal(Env<AttrContext> env, Type site,
2547 Name name, KindSelector kind) {
2548 Symbol bestSoFar = typeNotFound;
2549 Symbol sym;
2550 if (kind.contains(KindSelector.VAL)) {
2551 sym = findField(env, site, name, site.tsym);
2552 if (sym.exists()) return sym;
2553 else bestSoFar = bestOf(bestSoFar, sym);
2554 }
2555
2556 if (kind.contains(KindSelector.TYP)) {
2557 sym = findMemberType(env, site, name, site.tsym);
2558 if (sym.exists()) return sym;
2559 else bestSoFar = bestOf(bestSoFar, sym);
2560 }
2561 return bestSoFar;
2562 }
2563
2564 private Symbol checkRestrictedType(DiagnosticPosition pos, Symbol bestSoFar, Name name) {
2565 if (bestSoFar.kind == TYP || bestSoFar.kind == ABSENT_TYP) {
2566 if (allowLocalVariableTypeInference && name.equals(names.var)) {
2567 bestSoFar = new BadRestrictedTypeError(names.var);
2568 } else if (name.equals(names.yield)) {
2569 if (allowYieldStatement) {
2570 bestSoFar = new BadRestrictedTypeError(names.yield);
2571 } else if (pos != null) {
2572 log.warning(pos, Warnings.IllegalRefToRestrictedType(names.yield));
2573 }
2574 }
2575 }
2576 return bestSoFar;
2577 }
2578
2579 /* ***************************************************************************
2580 * Access checking
2581 * The following methods convert ResolveErrors to ErrorSymbols, issuing
2582 * an error message in the process
2583 ****************************************************************************/
2584
2585 /** If `sym' is a bad symbol: report error and return errSymbol
2586 * else pass through unchanged,
2587 * additional arguments duplicate what has been used in trying to find the
2588 * symbol {@literal (--> flyweight pattern)}. This improves performance since we
2589 * expect misses to happen frequently.
2590 *
2591 * @param sym The symbol that was found, or a ResolveError.
2592 * @param pos The position to use for error reporting.
2593 * @param location The symbol the served as a context for this lookup
2594 * @param site The original type from where the selection took place.
2595 * @param name The symbol's name.
2596 * @param qualified Did we get here through a qualified expression resolution?
2597 * @param argtypes The invocation's value arguments,
2598 * if we looked for a method.
2599 * @param typeargtypes The invocation's type arguments,
2600 * if we looked for a method.
2601 * @param logResolveHelper helper class used to log resolve errors
2602 */
2603 Symbol accessInternal(Symbol sym,
2604 DiagnosticPosition pos,
2605 Symbol location,
2606 Type site,
2607 Name name,
2608 boolean qualified,
2609 List<Type> argtypes,
2610 List<Type> typeargtypes,
2611 LogResolveHelper logResolveHelper) {
2612 if (sym.kind.isResolutionError()) {
2613 ResolveError errSym = (ResolveError)sym.baseSymbol();
2614 sym = errSym.access(name, qualified ? site.tsym : syms.noSymbol);
2615 argtypes = logResolveHelper.getArgumentTypes(errSym, sym, name, argtypes);
2616 if (logResolveHelper.resolveDiagnosticNeeded(site, argtypes, typeargtypes)) {
2617 logResolveError(errSym, pos, location, site, name, argtypes, typeargtypes);
2618 }
2619 }
2620 return sym;
2621 }
2622
2623 /**
2624 * Variant of the generalized access routine, to be used for generating method
2625 * resolution diagnostics
2626 */
2627 Symbol accessMethod(Symbol sym,
2628 DiagnosticPosition pos,
2629 Symbol location,
2630 Type site,
2631 Name name,
2632 boolean qualified,
2633 List<Type> argtypes,
2634 List<Type> typeargtypes) {
2635 return accessInternal(sym, pos, location, site, name, qualified, argtypes, typeargtypes, methodLogResolveHelper);
2636 }
2637
2638 /** Same as original accessMethod(), but without location.
2639 */
2640 Symbol accessMethod(Symbol sym,
2641 DiagnosticPosition pos,
2642 Type site,
2643 Name name,
2644 boolean qualified,
2645 List<Type> argtypes,
2646 List<Type> typeargtypes) {
2647 return accessMethod(sym, pos, site.tsym, site, name, qualified, argtypes, typeargtypes);
2648 }
2649
2650 /**
2651 * Variant of the generalized access routine, to be used for generating variable,
2652 * type resolution diagnostics
2653 */
2654 Symbol accessBase(Symbol sym,
2655 DiagnosticPosition pos,
2656 Symbol location,
2657 Type site,
2658 Name name,
2659 boolean qualified) {
2660 return accessInternal(sym, pos, location, site, name, qualified, List.nil(), null, basicLogResolveHelper);
2661 }
2662
2663 /** Same as original accessBase(), but without location.
2664 */
2665 Symbol accessBase(Symbol sym,
2666 DiagnosticPosition pos,
2667 Type site,
2668 Name name,
2669 boolean qualified) {
2670 return accessBase(sym, pos, site.tsym, site, name, qualified);
2671 }
2672
2673 interface LogResolveHelper {
2674 boolean resolveDiagnosticNeeded(Type site, List<Type> argtypes, List<Type> typeargtypes);
2675 List<Type> getArgumentTypes(ResolveError errSym, Symbol accessedSym, Name name, List<Type> argtypes);
2676 }
2677
2678 LogResolveHelper basicLogResolveHelper = new LogResolveHelper() {
2679 public boolean resolveDiagnosticNeeded(Type site, List<Type> argtypes, List<Type> typeargtypes) {
2680 return !site.isErroneous();
2681 }
2682 public List<Type> getArgumentTypes(ResolveError errSym, Symbol accessedSym, Name name, List<Type> argtypes) {
2683 return argtypes;
2684 }
2685 };
2686
2687 LogResolveHelper silentLogResolveHelper = new LogResolveHelper() {
2688 public boolean resolveDiagnosticNeeded(Type site, List<Type> argtypes, List<Type> typeargtypes) {
2689 return false;
2690 }
2691 public List<Type> getArgumentTypes(ResolveError errSym, Symbol accessedSym, Name name, List<Type> argtypes) {
2692 return argtypes;
2693 }
2694 };
2695
2696 LogResolveHelper methodLogResolveHelper = new LogResolveHelper() {
2697 public boolean resolveDiagnosticNeeded(Type site, List<Type> argtypes, List<Type> typeargtypes) {
2698 return !site.isErroneous() &&
2699 !Type.isErroneous(argtypes) &&
2700 (typeargtypes == null || !Type.isErroneous(typeargtypes));
2701 }
2702 public List<Type> getArgumentTypes(ResolveError errSym, Symbol accessedSym, Name name, List<Type> argtypes) {
2703 return argtypes.map(new ResolveDeferredRecoveryMap(AttrMode.SPECULATIVE, accessedSym, currentResolutionContext.step));
2704 }
2705 };
2706
2707 class ResolveDeferredRecoveryMap extends DeferredAttr.RecoveryDeferredTypeMap {
2708
2709 public ResolveDeferredRecoveryMap(AttrMode mode, Symbol msym, MethodResolutionPhase step) {
2710 deferredAttr.super(mode, msym, step);
2711 }
2712
2713 @Override
2714 protected Type typeOf(DeferredType dt, Type pt) {
2715 Type res = super.typeOf(dt, pt);
2716 if (!res.isErroneous()) {
2717 switch (TreeInfo.skipParens(dt.tree).getTag()) {
2718 case LAMBDA:
2719 case REFERENCE:
2720 return dt;
2721 case CONDEXPR:
2722 return res == Type.recoveryType ?
2723 dt : res;
2724 }
2725 }
2726 return res;
2727 }
2728 }
2729
2730 /** Check that sym is not an abstract method.
2731 */
2732 void checkNonAbstract(DiagnosticPosition pos, Symbol sym) {
2733 if ((sym.flags() & ABSTRACT) != 0 && (sym.flags() & DEFAULT) == 0)
2734 log.error(pos,
2735 Errors.AbstractCantBeAccessedDirectly(kindName(sym),sym, sym.location()));
2736 }
2737
2738 /* ***************************************************************************
2739 * Name resolution
2740 * Naming conventions are as for symbol lookup
2741 * Unlike the find... methods these methods will report access errors
2742 ****************************************************************************/
2743
2744 /** Resolve an unqualified (non-method) identifier.
2745 * @param pos The position to use for error reporting.
2746 * @param env The environment current at the identifier use.
2747 * @param name The identifier's name.
2748 * @param kind The set of admissible symbol kinds for the identifier.
2749 */
2750 Symbol resolveIdent(DiagnosticPosition pos, Env<AttrContext> env,
2751 Name name, KindSelector kind) {
2752 return accessBase(
2753 findIdent(pos, env, name, kind),
2754 pos, env.enclClass.sym.type, name, false);
2755 }
2756
2757 /** Resolve an unqualified method identifier.
2758 * @param pos The position to use for error reporting.
2759 * @param env The environment current at the method invocation.
2760 * @param name The identifier's name.
2761 * @param argtypes The types of the invocation's value arguments.
2762 * @param typeargtypes The types of the invocation's type arguments.
2763 */
2764 Symbol resolveMethod(DiagnosticPosition pos,
2765 Env<AttrContext> env,
2766 Name name,
2767 List<Type> argtypes,
2768 List<Type> typeargtypes) {
2769 return lookupMethod(env, pos, env.enclClass.sym, resolveMethodCheck,
2770 new BasicLookupHelper(name, env.enclClass.sym.type, argtypes, typeargtypes) {
2771 @Override
2772 Symbol lookup(Env<AttrContext> env, MethodResolutionPhase phase) {
2773 return findFun(env, name, argtypes, typeargtypes,
2774 phase.isBoxingRequired(),
2775 phase.isVarargsRequired());
2776 }});
2777 }
2778
2779 /** Resolve a qualified method identifier
2780 * @param pos The position to use for error reporting.
2781 * @param env The environment current at the method invocation.
2782 * @param site The type of the qualifying expression, in which
2783 * identifier is searched.
2784 * @param name The identifier's name.
2785 * @param argtypes The types of the invocation's value arguments.
2786 * @param typeargtypes The types of the invocation's type arguments.
2787 */
2788 Symbol resolveQualifiedMethod(DiagnosticPosition pos, Env<AttrContext> env,
2789 Type site, Name name, List<Type> argtypes,
2790 List<Type> typeargtypes) {
2791 return resolveQualifiedMethod(pos, env, site.tsym, site, name, argtypes, typeargtypes);
2792 }
2793 Symbol resolveQualifiedMethod(DiagnosticPosition pos, Env<AttrContext> env,
2794 Symbol location, Type site, Name name, List<Type> argtypes,
2795 List<Type> typeargtypes) {
2796 return resolveQualifiedMethod(new MethodResolutionContext(), pos, env, location, site, name, argtypes, typeargtypes);
2797 }
2798 private Symbol resolveQualifiedMethod(MethodResolutionContext resolveContext,
2799 DiagnosticPosition pos, Env<AttrContext> env,
2800 Symbol location, Type site, Name name, List<Type> argtypes,
2801 List<Type> typeargtypes) {
2802 return lookupMethod(env, pos, location, resolveContext, new BasicLookupHelper(name, site, argtypes, typeargtypes) {
2803 @Override
2804 Symbol lookup(Env<AttrContext> env, MethodResolutionPhase phase) {
2805 return findMethod(env, site, name, argtypes, typeargtypes,
2806 phase.isBoxingRequired(),
2807 phase.isVarargsRequired());
2808 }
2809 @Override
2810 Symbol access(Env<AttrContext> env, DiagnosticPosition pos, Symbol location, Symbol sym) {
2811 if (sym.kind.isResolutionError()) {
2812 sym = super.access(env, pos, location, sym);
2813 } else {
2814 MethodSymbol msym = (MethodSymbol)sym;
2815 if ((msym.flags() & SIGNATURE_POLYMORPHIC) != 0) {
2816 env.info.pendingResolutionPhase = BASIC;
2817 return findPolymorphicSignatureInstance(env, sym, argtypes);
2818 }
2819 }
2820 return sym;
2821 }
2822 });
2823 }
2824
2825 /** Find or create an implicit method of exactly the given type (after erasure).
2826 * Searches in a side table, not the main scope of the site.
2827 * This emulates the lookup process required by JSR 292 in JVM.
2828 * @param env Attribution environment
2829 * @param spMethod signature polymorphic method - i.e. MH.invokeExact
2830 * @param argtypes The required argument types
2831 */
2832 Symbol findPolymorphicSignatureInstance(Env<AttrContext> env,
2833 final Symbol spMethod,
2834 List<Type> argtypes) {
2835 Type mtype = infer.instantiatePolymorphicSignatureInstance(env,
2836 (MethodSymbol)spMethod, currentResolutionContext, argtypes);
2837 return findPolymorphicSignatureInstance(spMethod, mtype);
2838 }
2839
2840 Symbol findPolymorphicSignatureInstance(final Symbol spMethod,
2841 Type mtype) {
2842 for (Symbol sym : polymorphicSignatureScope.getSymbolsByName(spMethod.name)) {
2843 // Check that there is already a method symbol for the method
2844 // type and owner
2845 if (types.isSameType(mtype, sym.type) &&
2846 spMethod.owner == sym.owner) {
2847 return sym;
2848 }
2849 }
2850
2851 Type spReturnType = spMethod.asType().getReturnType();
2852 if (types.isSameType(spReturnType, syms.objectType)) {
2853 // Polymorphic return, pass through mtype
2854 } else if (!types.isSameType(spReturnType, mtype.getReturnType())) {
2855 // Retain the sig poly method's return type, which differs from that of mtype
2856 // Will result in an incompatible return type error
2857 mtype = new MethodType(mtype.getParameterTypes(),
2858 spReturnType,
2859 mtype.getThrownTypes(),
2860 syms.methodClass);
2861 }
2862
2863 // Create the desired method
2864 // Retain static modifier is to support invocations to
2865 // MethodHandle.linkTo* methods
2866 long flags = ABSTRACT | HYPOTHETICAL |
2867 spMethod.flags() & (Flags.AccessFlags | Flags.STATIC);
2868 Symbol msym = new MethodSymbol(flags, spMethod.name, mtype, spMethod.owner) {
2869 @Override
2870 public Symbol baseSymbol() {
2871 return spMethod;
2872 }
2873 };
2874 if (!mtype.isErroneous()) { // Cache only if kosher.
2875 polymorphicSignatureScope.enter(msym);
2876 }
2877 return msym;
2878 }
2879
2880 /** Resolve a qualified method identifier, throw a fatal error if not
2881 * found.
2882 * @param pos The position to use for error reporting.
2883 * @param env The environment current at the method invocation.
2884 * @param site The type of the qualifying expression, in which
2885 * identifier is searched.
2886 * @param name The identifier's name.
2887 * @param argtypes The types of the invocation's value arguments.
2888 * @param typeargtypes The types of the invocation's type arguments.
2889 */
2890 public MethodSymbol resolveInternalMethod(DiagnosticPosition pos, Env<AttrContext> env,
2891 Type site, Name name,
2892 List<Type> argtypes,
2893 List<Type> typeargtypes) {
2894 MethodResolutionContext resolveContext = new MethodResolutionContext();
2895 resolveContext.internalResolution = true;
2896 Symbol sym = resolveQualifiedMethod(resolveContext, pos, env, site.tsym,
2897 site, name, argtypes, typeargtypes);
2898 if (sym.kind == MTH) return (MethodSymbol)sym;
2899 else throw new FatalError(
2900 diags.fragment(Fragments.FatalErrCantLocateMeth(name)));
2901 }
2902
2903 /** Resolve constructor.
2904 * @param pos The position to use for error reporting.
2905 * @param env The environment current at the constructor invocation.
2906 * @param site The type of class for which a constructor is searched.
2907 * @param argtypes The types of the constructor invocation's value
2908 * arguments.
2909 * @param typeargtypes The types of the constructor invocation's type
2910 * arguments.
2911 */
2912 Symbol resolveConstructor(DiagnosticPosition pos,
2913 Env<AttrContext> env,
2914 Type site,
2915 List<Type> argtypes,
2916 List<Type> typeargtypes) {
2917 return resolveConstructor(new MethodResolutionContext(), pos, env, site, argtypes, typeargtypes);
2918 }
2919
2920 private Symbol resolveConstructor(MethodResolutionContext resolveContext,
2921 final DiagnosticPosition pos,
2922 Env<AttrContext> env,
2923 Type site,
2924 List<Type> argtypes,
2925 List<Type> typeargtypes) {
2926 return lookupMethod(env, pos, site.tsym, resolveContext, new BasicLookupHelper(names.init, site, argtypes, typeargtypes) {
2927 @Override
2928 Symbol lookup(Env<AttrContext> env, MethodResolutionPhase phase) {
2929 return findConstructor(pos, env, site, argtypes, typeargtypes,
2930 phase.isBoxingRequired(),
2931 phase.isVarargsRequired());
2932 }
2933 });
2934 }
2935
2936 /** Resolve a constructor, throw a fatal error if not found.
2937 * @param pos The position to use for error reporting.
2938 * @param env The environment current at the method invocation.
2939 * @param site The type to be constructed.
2940 * @param argtypes The types of the invocation's value arguments.
2941 * @param typeargtypes The types of the invocation's type arguments.
2942 */
2943 public MethodSymbol resolveInternalConstructor(DiagnosticPosition pos, Env<AttrContext> env,
2944 Type site,
2945 List<Type> argtypes,
2946 List<Type> typeargtypes) {
2947 MethodResolutionContext resolveContext = new MethodResolutionContext();
2948 resolveContext.internalResolution = true;
2949 Symbol sym = resolveConstructor(resolveContext, pos, env, site, argtypes, typeargtypes);
2950 if (sym.kind == MTH) return (MethodSymbol)sym;
2951 else throw new FatalError(
2952 diags.fragment(Fragments.FatalErrCantLocateCtor(site)));
2953 }
2954
2955 Symbol findConstructor(DiagnosticPosition pos, Env<AttrContext> env,
2956 Type site, List<Type> argtypes,
2957 List<Type> typeargtypes,
2958 boolean allowBoxing,
2959 boolean useVarargs) {
2960 Symbol sym = findMethod(env, site,
2961 names.init, argtypes,
2962 typeargtypes, allowBoxing,
2963 useVarargs);
2964 chk.checkDeprecated(pos, env.info.scope.owner, sym);
2965 chk.checkPreview(pos, env.info.scope.owner, sym);
2966 return sym;
2967 }
2968
2969 /** Resolve constructor using diamond inference.
2970 * @param pos The position to use for error reporting.
2971 * @param env The environment current at the constructor invocation.
2972 * @param site The type of class for which a constructor is searched.
2973 * The scope of this class has been touched in attribution.
2974 * @param argtypes The types of the constructor invocation's value
2975 * arguments.
2976 * @param typeargtypes The types of the constructor invocation's type
2977 * arguments.
2978 */
2979 Symbol resolveDiamond(DiagnosticPosition pos,
2980 Env<AttrContext> env,
2981 Type site,
2982 List<Type> argtypes,
2983 List<Type> typeargtypes) {
2984 return lookupMethod(env, pos, site.tsym, resolveMethodCheck,
2985 new BasicLookupHelper(names.init, site, argtypes, typeargtypes) {
2986 @Override
2987 Symbol lookup(Env<AttrContext> env, MethodResolutionPhase phase) {
2988 return findDiamond(pos, env, site, argtypes, typeargtypes,
2989 phase.isBoxingRequired(),
2990 phase.isVarargsRequired());
2991 }
2992 @Override
2993 Symbol access(Env<AttrContext> env, DiagnosticPosition pos, Symbol location, Symbol sym) {
2994 if (sym.kind.isResolutionError()) {
2995 if (sym.kind != WRONG_MTH &&
2996 sym.kind != WRONG_MTHS) {
2997 sym = super.access(env, pos, location, sym);
2998 } else {
2999 sym = new DiamondError(sym, currentResolutionContext);
3000 sym = accessMethod(sym, pos, site, names.init, true, argtypes, typeargtypes);
3001 env.info.pendingResolutionPhase = currentResolutionContext.step;
3002 }
3003 }
3004 return sym;
3005 }});
3006 }
3007
3008 /** Find the constructor using diamond inference and do some checks(deprecated and preview).
3009 * @param pos The position to use for error reporting.
3010 * @param env The environment current at the constructor invocation.
3011 * @param site The type of class for which a constructor is searched.
3012 * The scope of this class has been touched in attribution.
3013 * @param argtypes The types of the constructor invocation's value arguments.
3014 * @param typeargtypes The types of the constructor invocation's type arguments.
3015 * @param allowBoxing Allow boxing conversions of arguments.
3016 * @param useVarargs Box trailing arguments into an array for varargs.
3017 */
3018 private Symbol findDiamond(DiagnosticPosition pos,
3019 Env<AttrContext> env,
3020 Type site,
3021 List<Type> argtypes,
3022 List<Type> typeargtypes,
3023 boolean allowBoxing,
3024 boolean useVarargs) {
3025 Symbol sym = findDiamond(env, site, argtypes, typeargtypes, allowBoxing, useVarargs);
3026 chk.checkDeprecated(pos, env.info.scope.owner, sym);
3027 chk.checkPreview(pos, env.info.scope.owner, sym);
3028 return sym;
3029 }
3030
3031 /** This method scans all the constructor symbol in a given class scope -
3032 * assuming that the original scope contains a constructor of the kind:
3033 * {@code Foo(X x, Y y)}, where X,Y are class type-variables declared in Foo,
3034 * a method check is executed against the modified constructor type:
3035 * {@code <X,Y>Foo<X,Y>(X x, Y y)}. This is crucial in order to enable diamond
3036 * inference. The inferred return type of the synthetic constructor IS
3037 * the inferred type for the diamond operator.
3038 */
3039 private Symbol findDiamond(Env<AttrContext> env,
3040 Type site,
3041 List<Type> argtypes,
3042 List<Type> typeargtypes,
3043 boolean allowBoxing,
3044 boolean useVarargs) {
3045 Symbol bestSoFar = methodNotFound;
3046 TypeSymbol tsym = site.tsym.isInterface() ? syms.objectType.tsym : site.tsym;
3047 for (final Symbol sym : tsym.members().getSymbolsByName(names.init)) {
3048 //- System.out.println(" e " + e.sym);
3049 if (sym.kind == MTH &&
3050 (sym.flags_field & SYNTHETIC) == 0) {
3051 List<Type> oldParams = sym.type.hasTag(FORALL) ?
3052 ((ForAll)sym.type).tvars :
3053 List.nil();
3054 Type constrType = new ForAll(site.tsym.type.getTypeArguments().appendList(oldParams),
3055 types.createMethodTypeWithReturn(sym.type.asMethodType(), site));
3056 MethodSymbol newConstr = new MethodSymbol(sym.flags(), names.init, constrType, site.tsym) {
3057 @Override
3058 public Symbol baseSymbol() {
3059 return sym;
3060 }
3061 };
3062 bestSoFar = selectBest(env, site, argtypes, typeargtypes,
3063 newConstr,
3064 bestSoFar,
3065 allowBoxing,
3066 useVarargs);
3067 }
3068 }
3069 return bestSoFar;
3070 }
3071
3072 Symbol getMemberReference(DiagnosticPosition pos,
3073 Env<AttrContext> env,
3074 JCMemberReference referenceTree,
3075 Type site,
3076 Name name) {
3077
3078 site = types.capture(site);
3079
3080 ReferenceLookupHelper lookupHelper = makeReferenceLookupHelper(
3081 referenceTree, site, name, List.nil(), null, VARARITY);
3082
3083 Env<AttrContext> newEnv = env.dup(env.tree, env.info.dup());
3084 Symbol sym = lookupMethod(newEnv, env.tree.pos(), site.tsym,
3085 nilMethodCheck, lookupHelper);
3086
3087 env.info.pendingResolutionPhase = newEnv.info.pendingResolutionPhase;
3088
3089 return sym;
3090 }
3091
3092 ReferenceLookupHelper makeReferenceLookupHelper(JCMemberReference referenceTree,
3093 Type site,
3094 Name name,
3095 List<Type> argtypes,
3096 List<Type> typeargtypes,
3097 MethodResolutionPhase maxPhase) {
3098 if (!name.equals(names.init)) {
3099 //method reference
3100 return new MethodReferenceLookupHelper(referenceTree, name, site, argtypes, typeargtypes, maxPhase);
3101 } else if (site.hasTag(ARRAY)) {
3102 //array constructor reference
3103 return new ArrayConstructorReferenceLookupHelper(referenceTree, site, argtypes, typeargtypes, maxPhase);
3104 } else {
3105 //class constructor reference
3106 return new ConstructorReferenceLookupHelper(referenceTree, site, argtypes, typeargtypes, maxPhase);
3107 }
3108 }
3109
3110 /**
3111 * Resolution of member references is typically done as a single
3112 * overload resolution step, where the argument types A are inferred from
3113 * the target functional descriptor.
3114 *
3115 * If the member reference is a method reference with a type qualifier,
3116 * a two-step lookup process is performed. The first step uses the
3117 * expected argument list A, while the second step discards the first
3118 * type from A (which is treated as a receiver type).
3119 *
3120 * There are two cases in which inference is performed: (i) if the member
3121 * reference is a constructor reference and the qualifier type is raw - in
3122 * which case diamond inference is used to infer a parameterization for the
3123 * type qualifier; (ii) if the member reference is an unbound reference
3124 * where the type qualifier is raw - in that case, during the unbound lookup
3125 * the receiver argument type is used to infer an instantiation for the raw
3126 * qualifier type.
3127 *
3128 * When a multi-step resolution process is exploited, the process of picking
3129 * the resulting symbol is delegated to an helper class {@link com.sun.tools.javac.comp.Resolve.ReferenceChooser}.
3130 *
3131 * This routine returns a pair (T,S), where S is the member reference symbol,
3132 * and T is the type of the class in which S is defined. This is necessary as
3133 * the type T might be dynamically inferred (i.e. if constructor reference
3134 * has a raw qualifier).
3135 */
3136 Pair<Symbol, ReferenceLookupHelper> resolveMemberReference(Env<AttrContext> env,
3137 JCMemberReference referenceTree,
3138 Type site,
3139 Name name,
3140 List<Type> argtypes,
3141 List<Type> typeargtypes,
3142 Type descriptor,
3143 MethodCheck methodCheck,
3144 InferenceContext inferenceContext,
3145 ReferenceChooser referenceChooser) {
3146
3147 //step 1 - bound lookup
3148 ReferenceLookupHelper boundLookupHelper = makeReferenceLookupHelper(
3149 referenceTree, site, name, argtypes, typeargtypes, VARARITY);
3150 Env<AttrContext> boundEnv = env.dup(env.tree, env.info.dup());
3151 MethodResolutionContext boundSearchResolveContext = new MethodResolutionContext();
3152 boundSearchResolveContext.methodCheck = methodCheck;
3153 Symbol boundSym = lookupMethod(boundEnv, env.tree.pos(),
3154 site.tsym, boundSearchResolveContext, boundLookupHelper);
3155 boolean isStaticSelector = TreeInfo.isStaticSelector(referenceTree.expr, names);
3156 ReferenceLookupResult boundRes = new ReferenceLookupResult(boundSym, boundSearchResolveContext, isStaticSelector);
3157 if (dumpMethodReferenceSearchResults) {
3158 dumpMethodReferenceSearchResults(referenceTree, boundSearchResolveContext, boundSym, true);
3159 }
3160
3161 //step 2 - unbound lookup
3162 Symbol unboundSym = methodNotFound;
3163 Env<AttrContext> unboundEnv = env.dup(env.tree, env.info.dup());
3164 ReferenceLookupHelper unboundLookupHelper = boundLookupHelper.unboundLookup(inferenceContext);
3165 ReferenceLookupResult unboundRes = referenceNotFound;
3166 if (unboundLookupHelper != null) {
3167 MethodResolutionContext unboundSearchResolveContext =
3168 new MethodResolutionContext();
3169 unboundSearchResolveContext.methodCheck = methodCheck;
3170 unboundSym = lookupMethod(unboundEnv, env.tree.pos(),
3171 site.tsym, unboundSearchResolveContext, unboundLookupHelper);
3172 unboundRes = new ReferenceLookupResult(unboundSym, unboundSearchResolveContext, isStaticSelector);
3173 if (dumpMethodReferenceSearchResults) {
3174 dumpMethodReferenceSearchResults(referenceTree, unboundSearchResolveContext, unboundSym, false);
3175 }
3176 }
3177
3178 //merge results
3179 Pair<Symbol, ReferenceLookupHelper> res;
3180 ReferenceLookupResult bestRes = referenceChooser.result(boundRes, unboundRes);
3181 res = new Pair<>(bestRes.sym,
3182 bestRes == unboundRes ? unboundLookupHelper : boundLookupHelper);
3183 env.info.pendingResolutionPhase = bestRes == unboundRes ?
3184 unboundEnv.info.pendingResolutionPhase :
3185 boundEnv.info.pendingResolutionPhase;
3186
3187 if (!res.fst.kind.isResolutionError()) {
3188 //handle sigpoly method references
3189 MethodSymbol msym = (MethodSymbol)res.fst;
3190 if ((msym.flags() & SIGNATURE_POLYMORPHIC) != 0) {
3191 env.info.pendingResolutionPhase = BASIC;
3192 res = new Pair<>(findPolymorphicSignatureInstance(msym, descriptor), res.snd);
3193 }
3194 }
3195
3196 return res;
3197 }
3198
3199 private void dumpMethodReferenceSearchResults(JCMemberReference referenceTree,
3200 MethodResolutionContext resolutionContext,
3201 Symbol bestSoFar,
3202 boolean bound) {
3203 ListBuffer<JCDiagnostic> subDiags = new ListBuffer<>();
3204 int pos = 0;
3205 int mostSpecificPos = -1;
3206 for (Candidate c : resolutionContext.candidates) {
3207 if (resolutionContext.step != c.step || !c.isApplicable()) {
3208 continue;
3209 } else {
3210 JCDiagnostic subDiag = null;
3211 if (c.sym.type.hasTag(FORALL)) {
3212 subDiag = diags.fragment(Fragments.PartialInstSig(c.mtype));
3213 }
3214
3215 String key = subDiag == null ?
3216 "applicable.method.found.2" :
3217 "applicable.method.found.3";
3218 subDiags.append(diags.fragment(key, pos,
3219 c.sym.isStatic() ? Fragments.Static : Fragments.NonStatic, c.sym, subDiag));
3220 if (c.sym == bestSoFar)
3221 mostSpecificPos = pos;
3222 pos++;
3223 }
3224 }
3225 JCDiagnostic main = diags.note(
3226 log.currentSource(),
3227 referenceTree,
3228 "method.ref.search.results.multi",
3229 bound ? Fragments.Bound : Fragments.Unbound,
3230 referenceTree.toString(), mostSpecificPos);
3231 JCDiagnostic d = new JCDiagnostic.MultilineDiagnostic(main, subDiags.toList());
3232 log.report(d);
3233 }
3234
3235 /**
3236 * This class is used to represent a method reference lookup result. It keeps track of two
3237 * things: (i) the symbol found during a method reference lookup and (ii) the static kind
3238 * of the lookup (see {@link com.sun.tools.javac.comp.Resolve.ReferenceLookupResult.StaticKind}).
3239 */
3240 static class ReferenceLookupResult {
3241
3242 /**
3243 * Static kind associated with a method reference lookup. Erroneous lookups end up with
3244 * the UNDEFINED kind; successful lookups will end up with either STATIC, NON_STATIC,
3245 * depending on whether all applicable candidates are static or non-static methods,
3246 * respectively. If a successful lookup has both static and non-static applicable methods,
3247 * its kind is set to BOTH.
3248 */
3249 enum StaticKind {
3250 STATIC,
3251 NON_STATIC,
3252 BOTH,
3253 UNDEFINED;
3254
3255 /**
3256 * Retrieve the static kind associated with a given (method) symbol.
3257 */
3258 static StaticKind from(Symbol s) {
3259 return s.isStatic() ?
3260 STATIC : NON_STATIC;
3261 }
3262
3263 /**
3264 * Merge two static kinds together.
3265 */
3266 static StaticKind reduce(StaticKind sk1, StaticKind sk2) {
3267 if (sk1 == UNDEFINED) {
3268 return sk2;
3269 } else if (sk2 == UNDEFINED) {
3270 return sk1;
3271 } else {
3272 return sk1 == sk2 ? sk1 : BOTH;
3273 }
3274 }
3275 }
3276
3277 /** The static kind. */
3278 StaticKind staticKind;
3279
3280 /** The lookup result. */
3281 Symbol sym;
3282
3283 ReferenceLookupResult(Symbol sym, MethodResolutionContext resolutionContext, boolean isStaticSelector) {
3284 this(sym, staticKind(sym, resolutionContext, isStaticSelector));
3285 }
3286
3287 private ReferenceLookupResult(Symbol sym, StaticKind staticKind) {
3288 this.staticKind = staticKind;
3289 this.sym = sym;
3290 }
3291
3292 private static StaticKind staticKind(Symbol sym, MethodResolutionContext resolutionContext, boolean isStaticSelector) {
3293 if (sym.kind == MTH && !isStaticSelector) {
3294 return StaticKind.from(sym);
3295 } else if (sym.kind == MTH || sym.kind == AMBIGUOUS) {
3296 return resolutionContext.candidates.stream()
3297 .filter(c -> c.isApplicable() && c.step == resolutionContext.step)
3298 .map(c -> StaticKind.from(c.sym))
3299 .reduce(StaticKind::reduce)
3300 .orElse(StaticKind.UNDEFINED);
3301 } else {
3302 return StaticKind.UNDEFINED;
3303 }
3304 }
3305
3306 /**
3307 * Does this result corresponds to a successful lookup (i.e. one where a method has been found?)
3308 */
3309 boolean isSuccess() {
3310 return staticKind != StaticKind.UNDEFINED;
3311 }
3312
3313 /**
3314 * Does this result have given static kind?
3315 */
3316 boolean hasKind(StaticKind sk) {
3317 return this.staticKind == sk;
3318 }
3319
3320 /**
3321 * Error recovery helper: can this lookup result be ignored (for the purpose of returning
3322 * some 'better' result) ?
3323 */
3324 boolean canIgnore() {
3325 switch (sym.kind) {
3326 case ABSENT_MTH:
3327 return true;
3328 case WRONG_MTH:
3329 InapplicableSymbolError errSym =
3330 (InapplicableSymbolError)sym.baseSymbol();
3331 return new Template(MethodCheckDiag.ARITY_MISMATCH.regex())
3332 .matches(errSym.errCandidate().snd);
3333 case WRONG_MTHS:
3334 InapplicableSymbolsError errSyms =
3335 (InapplicableSymbolsError)sym.baseSymbol();
3336 return errSyms.filterCandidates(errSyms.mapCandidates()).isEmpty();
3337 default:
3338 return false;
3339 }
3340 }
3341
3342 static ReferenceLookupResult error(Symbol sym) {
3343 return new ReferenceLookupResult(sym, StaticKind.UNDEFINED);
3344 }
3345 }
3346
3347 /**
3348 * This abstract class embodies the logic that converts one (bound lookup) or two (unbound lookup)
3349 * {@code ReferenceLookupResult} objects into a {@code Symbol}, which is then regarded as the
3350 * result of method reference resolution.
3351 */
3352 abstract class ReferenceChooser {
3353 /**
3354 * Generate a result from a pair of lookup result objects. This method delegates to the
3355 * appropriate result generation routine.
3356 */
3357 ReferenceLookupResult result(ReferenceLookupResult boundRes, ReferenceLookupResult unboundRes) {
3358 return unboundRes != referenceNotFound ?
3359 unboundResult(boundRes, unboundRes) :
3360 boundResult(boundRes);
3361 }
3362
3363 /**
3364 * Generate a symbol from a given bound lookup result.
3365 */
3366 abstract ReferenceLookupResult boundResult(ReferenceLookupResult boundRes);
3367
3368 /**
3369 * Generate a symbol from a pair of bound/unbound lookup results.
3370 */
3371 abstract ReferenceLookupResult unboundResult(ReferenceLookupResult boundRes, ReferenceLookupResult unboundRes);
3372 }
3373
3374 /**
3375 * This chooser implements the selection strategy used during a full lookup; this logic
3376 * is described in JLS SE 8 (15.3.2).
3377 */
3378 ReferenceChooser basicReferenceChooser = new ReferenceChooser() {
3379
3380 @Override
3381 ReferenceLookupResult boundResult(ReferenceLookupResult boundRes) {
3382 return !boundRes.isSuccess() || boundRes.hasKind(StaticKind.NON_STATIC) ?
3383 boundRes : //the search produces a non-static method
3384 ReferenceLookupResult.error(new BadMethodReferenceError(boundRes.sym, false));
3385 }
3386
3387 @Override
3388 ReferenceLookupResult unboundResult(ReferenceLookupResult boundRes, ReferenceLookupResult unboundRes) {
3389 if (boundRes.isSuccess() && boundRes.sym.isStatic() &&
3390 (!unboundRes.isSuccess() || unboundRes.hasKind(StaticKind.STATIC))) {
3391 //the first search produces a static method and no non-static method is applicable
3392 //during the second search
3393 return boundRes;
3394 } else if (unboundRes.isSuccess() && !unboundRes.sym.isStatic() &&
3395 (!boundRes.isSuccess() || boundRes.hasKind(StaticKind.NON_STATIC))) {
3396 //the second search produces a non-static method and no static method is applicable
3397 //during the first search
3398 return unboundRes;
3399 } else if (boundRes.isSuccess() && unboundRes.isSuccess()) {
3400 //both searches produce some result; ambiguity (error recovery)
3401 return ReferenceLookupResult.error(ambiguityError(boundRes.sym, unboundRes.sym));
3402 } else if (boundRes.isSuccess() || unboundRes.isSuccess()) {
3403 //Both searches failed to produce a result with correct staticness (i.e. first search
3404 //produces an non-static method). Alternatively, a given search produced a result
3405 //with the right staticness, but the other search has applicable methods with wrong
3406 //staticness (error recovery)
3407 return ReferenceLookupResult.error(new BadMethodReferenceError(boundRes.isSuccess() ?
3408 boundRes.sym : unboundRes.sym, true));
3409 } else {
3410 //both searches fail to produce a result - pick 'better' error using heuristics (error recovery)
3411 return (boundRes.canIgnore() && !unboundRes.canIgnore()) ?
3412 unboundRes : boundRes;
3413 }
3414 }
3415 };
3416
3417 /**
3418 * This chooser implements the selection strategy used during an arity-based lookup; this logic
3419 * is described in JLS SE 8 (15.12.2.1).
3420 */
3421 ReferenceChooser structuralReferenceChooser = new ReferenceChooser() {
3422
3423 @Override
3424 ReferenceLookupResult boundResult(ReferenceLookupResult boundRes) {
3425 return (!boundRes.isSuccess() || !boundRes.hasKind(StaticKind.STATIC)) ?
3426 boundRes : //the search has at least one applicable non-static method
3427 ReferenceLookupResult.error(new BadMethodReferenceError(boundRes.sym, false));
3428 }
3429
3430 @Override
3431 ReferenceLookupResult unboundResult(ReferenceLookupResult boundRes, ReferenceLookupResult unboundRes) {
3432 if (boundRes.isSuccess() && !boundRes.hasKind(StaticKind.NON_STATIC)) {
3433 //the first search has at least one applicable static method
3434 return boundRes;
3435 } else if (unboundRes.isSuccess() && !unboundRes.hasKind(StaticKind.STATIC)) {
3436 //the second search has at least one applicable non-static method
3437 return unboundRes;
3438 } else if (boundRes.isSuccess() || unboundRes.isSuccess()) {
3439 //either the first search produces a non-static method, or second search produces
3440 //a non-static method (error recovery)
3441 return ReferenceLookupResult.error(new BadMethodReferenceError(boundRes.isSuccess() ?
3442 boundRes.sym : unboundRes.sym, true));
3443 } else {
3444 //both searches fail to produce a result - pick 'better' error using heuristics (error recovery)
3445 return (boundRes.canIgnore() && !unboundRes.canIgnore()) ?
3446 unboundRes : boundRes;
3447 }
3448 }
3449 };
3450
3451 /**
3452 * Helper for defining custom method-like lookup logic; a lookup helper
3453 * provides hooks for (i) the actual lookup logic and (ii) accessing the
3454 * lookup result (this step might result in compiler diagnostics to be generated)
3455 */
3456 abstract class LookupHelper {
3457
3458 /** name of the symbol to lookup */
3459 Name name;
3460
3461 /** location in which the lookup takes place */
3462 Type site;
3463
3464 /** actual types used during the lookup */
3465 List<Type> argtypes;
3466
3467 /** type arguments used during the lookup */
3468 List<Type> typeargtypes;
3469
3470 /** Max overload resolution phase handled by this helper */
3471 MethodResolutionPhase maxPhase;
3472
3473 LookupHelper(Name name, Type site, List<Type> argtypes, List<Type> typeargtypes, MethodResolutionPhase maxPhase) {
3474 this.name = name;
3475 this.site = site;
3476 this.argtypes = argtypes;
3477 this.typeargtypes = typeargtypes;
3478 this.maxPhase = maxPhase;
3479 }
3480
3481 /**
3482 * Should lookup stop at given phase with given result
3483 */
3484 final boolean shouldStop(Symbol sym, MethodResolutionPhase phase) {
3485 return phase.ordinal() > maxPhase.ordinal() ||
3486 !sym.kind.isResolutionError() || sym.kind == AMBIGUOUS || sym.kind == STATICERR;
3487 }
3488
3489 /**
3490 * Search for a symbol under a given overload resolution phase - this method
3491 * is usually called several times, once per each overload resolution phase
3492 */
3493 abstract Symbol lookup(Env<AttrContext> env, MethodResolutionPhase phase);
3494
3495 /**
3496 * Dump overload resolution info
3497 */
3498 void debug(DiagnosticPosition pos, Symbol sym) {
3499 //do nothing
3500 }
3501
3502 /**
3503 * Validate the result of the lookup
3504 */
3505 abstract Symbol access(Env<AttrContext> env, DiagnosticPosition pos, Symbol location, Symbol sym);
3506 }
3507
3508 abstract class BasicLookupHelper extends LookupHelper {
3509
3510 BasicLookupHelper(Name name, Type site, List<Type> argtypes, List<Type> typeargtypes) {
3511 this(name, site, argtypes, typeargtypes, MethodResolutionPhase.VARARITY);
3512 }
3513
3514 BasicLookupHelper(Name name, Type site, List<Type> argtypes, List<Type> typeargtypes, MethodResolutionPhase maxPhase) {
3515 super(name, site, argtypes, typeargtypes, maxPhase);
3516 }
3517
3518 @Override
3519 Symbol access(Env<AttrContext> env, DiagnosticPosition pos, Symbol location, Symbol sym) {
3520 if (sym.kind.isResolutionError()) {
3521 //if nothing is found return the 'first' error
3522 sym = accessMethod(sym, pos, location, site, name, true, argtypes, typeargtypes);
3523 }
3524 return sym;
3525 }
3526
3527 @Override
3528 void debug(DiagnosticPosition pos, Symbol sym) {
3529 reportVerboseResolutionDiagnostic(pos, name, site, argtypes, typeargtypes, sym);
3530 }
3531 }
3532
3533 /**
3534 * Helper class for member reference lookup. A reference lookup helper
3535 * defines the basic logic for member reference lookup; a method gives
3536 * access to an 'unbound' helper used to perform an unbound member
3537 * reference lookup.
3538 */
3539 abstract class ReferenceLookupHelper extends LookupHelper {
3540
3541 /** The member reference tree */
3542 JCMemberReference referenceTree;
3543
3544 ReferenceLookupHelper(JCMemberReference referenceTree, Name name, Type site,
3545 List<Type> argtypes, List<Type> typeargtypes, MethodResolutionPhase maxPhase) {
3546 super(name, site, argtypes, typeargtypes, maxPhase);
3547 this.referenceTree = referenceTree;
3548 }
3549
3550 /**
3551 * Returns an unbound version of this lookup helper. By default, this
3552 * method returns an dummy lookup helper.
3553 */
3554 ReferenceLookupHelper unboundLookup(InferenceContext inferenceContext) {
3555 return null;
3556 }
3557
3558 /**
3559 * Get the kind of the member reference
3560 */
3561 abstract JCMemberReference.ReferenceKind referenceKind(Symbol sym);
3562
3563 Symbol access(Env<AttrContext> env, DiagnosticPosition pos, Symbol location, Symbol sym) {
3564 //skip error reporting
3565 return sym;
3566 }
3567 }
3568
3569 /**
3570 * Helper class for method reference lookup. The lookup logic is based
3571 * upon Resolve.findMethod; in certain cases, this helper class has a
3572 * corresponding unbound helper class (see UnboundMethodReferenceLookupHelper).
3573 * In such cases, non-static lookup results are thrown away.
3574 */
3575 class MethodReferenceLookupHelper extends ReferenceLookupHelper {
3576
3577 /** The original method reference lookup site. */
3578 Type originalSite;
3579
3580 MethodReferenceLookupHelper(JCMemberReference referenceTree, Name name, Type site,
3581 List<Type> argtypes, List<Type> typeargtypes, MethodResolutionPhase maxPhase) {
3582 super(referenceTree, name, types.skipTypeVars(site, true), argtypes, typeargtypes, maxPhase);
3583 this.originalSite = site;
3584 }
3585
3586 @Override
3587 final Symbol lookup(Env<AttrContext> env, MethodResolutionPhase phase) {
3588 return findMethod(env, site, name, argtypes, typeargtypes,
3589 phase.isBoxingRequired(), phase.isVarargsRequired());
3590 }
3591
3592 @Override
3593 ReferenceLookupHelper unboundLookup(InferenceContext inferenceContext) {
3594 if (TreeInfo.isStaticSelector(referenceTree.expr, names)) {
3595 if (argtypes.nonEmpty() &&
3596 (argtypes.head.hasTag(NONE) ||
3597 types.isSubtypeUnchecked(inferenceContext.asUndetVar(argtypes.head), originalSite))) {
3598 return new UnboundMethodReferenceLookupHelper(referenceTree, name,
3599 originalSite, argtypes, typeargtypes, maxPhase);
3600 } else {
3601 return new ReferenceLookupHelper(referenceTree, name, site, argtypes, typeargtypes, maxPhase) {
3602 @Override
3603 ReferenceLookupHelper unboundLookup(InferenceContext inferenceContext) {
3604 return this;
3605 }
3606
3607 @Override
3608 Symbol lookup(Env<AttrContext> env, MethodResolutionPhase phase) {
3609 return methodNotFound;
3610 }
3611
3612 @Override
3613 ReferenceKind referenceKind(Symbol sym) {
3614 Assert.error();
3615 return null;
3616 }
3617 };
3618 }
3619 } else {
3620 return super.unboundLookup(inferenceContext);
3621 }
3622 }
3623
3624 @Override
3625 ReferenceKind referenceKind(Symbol sym) {
3626 if (sym.isStatic()) {
3627 return ReferenceKind.STATIC;
3628 } else {
3629 Name selName = TreeInfo.name(referenceTree.getQualifierExpression());
3630 return selName != null && selName == names._super ?
3631 ReferenceKind.SUPER :
3632 ReferenceKind.BOUND;
3633 }
3634 }
3635
3636 @Override
3637 Symbol access(Env<AttrContext> env, DiagnosticPosition pos, Symbol location, Symbol sym) {
3638 if (originalSite.hasTag(TYPEVAR) && sym.kind == MTH) {
3639 sym = (sym.flags() & Flags.PRIVATE) != 0 ?
3640 new AccessError(env, site, sym) :
3641 sym;
3642 return accessBase(sym, pos, location, originalSite, name, true);
3643 } else {
3644 return super.access(env, pos, location, sym);
3645 }
3646 }
3647 }
3648
3649 /**
3650 * Helper class for unbound method reference lookup. Essentially the same
3651 * as the basic method reference lookup helper; main difference is that static
3652 * lookup results are thrown away. If qualifier type is raw, an attempt to
3653 * infer a parameterized type is made using the first actual argument (that
3654 * would otherwise be ignored during the lookup).
3655 */
3656 class UnboundMethodReferenceLookupHelper extends MethodReferenceLookupHelper {
3657
3658 UnboundMethodReferenceLookupHelper(JCMemberReference referenceTree, Name name, Type site,
3659 List<Type> argtypes, List<Type> typeargtypes, MethodResolutionPhase maxPhase) {
3660 super(referenceTree, name, site, argtypes.tail, typeargtypes, maxPhase);
3661 if (site.isRaw() && !argtypes.head.hasTag(NONE)) {
3662 Type asSuperSite = types.asSuper(argtypes.head, site.tsym);
3663 this.site = types.skipTypeVars(asSuperSite, true);
3664 }
3665 }
3666
3667 @Override
3668 ReferenceLookupHelper unboundLookup(InferenceContext inferenceContext) {
3669 return this;
3670 }
3671
3672 @Override
3673 ReferenceKind referenceKind(Symbol sym) {
3674 return ReferenceKind.UNBOUND;
3675 }
3676 }
3677
3678 /**
3679 * Helper class for array constructor lookup; an array constructor lookup
3680 * is simulated by looking up a method that returns the array type specified
3681 * as qualifier, and that accepts a single int parameter (size of the array).
3682 */
3683 class ArrayConstructorReferenceLookupHelper extends ReferenceLookupHelper {
3684
3685 ArrayConstructorReferenceLookupHelper(JCMemberReference referenceTree, Type site, List<Type> argtypes,
3686 List<Type> typeargtypes, MethodResolutionPhase maxPhase) {
3687 super(referenceTree, names.init, site, argtypes, typeargtypes, maxPhase);
3688 }
3689
3690 @Override
3691 protected Symbol lookup(Env<AttrContext> env, MethodResolutionPhase phase) {
3692 WriteableScope sc = WriteableScope.create(syms.arrayClass);
3693 MethodSymbol arrayConstr = new MethodSymbol(PUBLIC, name, null, site.tsym);
3694 arrayConstr.type = new MethodType(List.of(syms.intType), site, List.nil(), syms.methodClass);
3695 sc.enter(arrayConstr);
3696 return findMethodInScope(env, site, name, argtypes, typeargtypes, sc, methodNotFound, phase.isBoxingRequired(), phase.isVarargsRequired(), false);
3697 }
3698
3699 @Override
3700 ReferenceKind referenceKind(Symbol sym) {
3701 return ReferenceKind.ARRAY_CTOR;
3702 }
3703 }
3704
3705 /**
3706 * Helper class for constructor reference lookup. The lookup logic is based
3707 * upon either Resolve.findMethod or Resolve.findDiamond - depending on
3708 * whether the constructor reference needs diamond inference (this is the case
3709 * if the qualifier type is raw). A special erroneous symbol is returned
3710 * if the lookup returns the constructor of an inner class and there's no
3711 * enclosing instance in scope.
3712 */
3713 class ConstructorReferenceLookupHelper extends ReferenceLookupHelper {
3714
3715 boolean needsInference;
3716
3717 ConstructorReferenceLookupHelper(JCMemberReference referenceTree, Type site, List<Type> argtypes,
3718 List<Type> typeargtypes, MethodResolutionPhase maxPhase) {
3719 super(referenceTree, names.init, site, argtypes, typeargtypes, maxPhase);
3720 if (site.isRaw()) {
3721 this.site = new ClassType(site.getEnclosingType(),
3722 !(site.tsym.isInner() && site.getEnclosingType().isRaw()) ?
3723 site.tsym.type.getTypeArguments() : List.nil(), site.tsym, site.getMetadata());
3724 needsInference = true;
3725 }
3726 }
3727
3728 @Override
3729 protected Symbol lookup(Env<AttrContext> env, MethodResolutionPhase phase) {
3730 Symbol sym = needsInference ?
3731 findDiamond(env, site, argtypes, typeargtypes, phase.isBoxingRequired(), phase.isVarargsRequired()) :
3732 findMethod(env, site, name, argtypes, typeargtypes,
3733 phase.isBoxingRequired(), phase.isVarargsRequired());
3734 return enclosingInstanceMissing(env, site) ? new BadConstructorReferenceError(sym) : sym;
3735 }
3736
3737 @Override
3738 ReferenceKind referenceKind(Symbol sym) {
3739 return site.getEnclosingType().hasTag(NONE) ?
3740 ReferenceKind.TOPLEVEL : ReferenceKind.IMPLICIT_INNER;
3741 }
3742 }
3743
3744 /**
3745 * Main overload resolution routine. On each overload resolution step, a
3746 * lookup helper class is used to perform the method/constructor lookup;
3747 * at the end of the lookup, the helper is used to validate the results
3748 * (this last step might trigger overload resolution diagnostics).
3749 */
3750 Symbol lookupMethod(Env<AttrContext> env, DiagnosticPosition pos, Symbol location, MethodCheck methodCheck, LookupHelper lookupHelper) {
3751 MethodResolutionContext resolveContext = new MethodResolutionContext();
3752 resolveContext.methodCheck = methodCheck;
3753 return lookupMethod(env, pos, location, resolveContext, lookupHelper);
3754 }
3755
3756 Symbol lookupMethod(Env<AttrContext> env, DiagnosticPosition pos, Symbol location,
3757 MethodResolutionContext resolveContext, LookupHelper lookupHelper) {
3758 MethodResolutionContext prevResolutionContext = currentResolutionContext;
3759 try {
3760 Symbol bestSoFar = methodNotFound;
3761 currentResolutionContext = resolveContext;
3762 for (MethodResolutionPhase phase : methodResolutionSteps) {
3763 if (lookupHelper.shouldStop(bestSoFar, phase))
3764 break;
3765 MethodResolutionPhase prevPhase = currentResolutionContext.step;
3766 Symbol prevBest = bestSoFar;
3767 currentResolutionContext.step = phase;
3768 Symbol sym = lookupHelper.lookup(env, phase);
3769 lookupHelper.debug(pos, sym);
3770 bestSoFar = phase.mergeResults(bestSoFar, sym);
3771 env.info.pendingResolutionPhase = (prevBest == bestSoFar) ? prevPhase : phase;
3772 }
3773 return lookupHelper.access(env, pos, location, bestSoFar);
3774 } finally {
3775 currentResolutionContext = prevResolutionContext;
3776 }
3777 }
3778
3779 /**
3780 * Resolve `c.name' where name == this or name == super.
3781 * @param pos The position to use for error reporting.
3782 * @param env The environment current at the expression.
3783 * @param c The qualifier.
3784 * @param name The identifier's name.
3785 */
3786 Symbol resolveSelf(DiagnosticPosition pos,
3787 Env<AttrContext> env,
3788 TypeSymbol c,
3789 Name name) {
3790 Assert.check(name == names._this || name == names._super);
3791 Env<AttrContext> env1 = env;
3792 boolean staticOnly = false;
3793 while (env1.outer != null) {
3794 if (isStatic(env1)) staticOnly = true;
3795 if (env1.enclClass.sym == c) {
3796 Symbol sym = env1.info.scope.findFirst(name);
3797 if (sym != null) {
3798 if (staticOnly)
3799 sym = new StaticError(sym);
3800 else if (env1.info.ctorPrologue && !isAllowedEarlyReference(pos, env1, (VarSymbol)sym))
3801 sym = new RefBeforeCtorCalledError(sym);
3802 return accessBase(sym, pos, env.enclClass.sym.type,
3803 name, true);
3804 }
3805 }
3806 if ((env1.enclClass.sym.flags() & STATIC) != 0) staticOnly = true;
3807 env1 = env1.outer;
3808 }
3809 if (c.isInterface() &&
3810 name == names._super && !isStatic(env) &&
3811 types.isDirectSuperInterface(c, env.enclClass.sym)) {
3812 //this might be a default super call if one of the superinterfaces is 'c'
3813 for (Type t : pruneInterfaces(env.enclClass.type)) {
3814 if (t.tsym == c) {
3815 if (env.info.ctorPrologue)
3816 log.error(pos, Errors.CantRefBeforeCtorCalled(name));
3817 env.info.defaultSuperCallSite = t;
3818 return new VarSymbol(0, names._super,
3819 types.asSuper(env.enclClass.type, c), env.enclClass.sym);
3820 }
3821 }
3822 //find a direct supertype that is a subtype of 'c'
3823 for (Type i : types.directSupertypes(env.enclClass.type)) {
3824 if (i.tsym.isSubClass(c, types) && i.tsym != c) {
3825 log.error(pos,
3826 Errors.IllegalDefaultSuperCall(c,
3827 Fragments.RedundantSupertype(c, i)));
3828 return syms.errSymbol;
3829 }
3830 }
3831 Assert.error();
3832 }
3833 log.error(pos, Errors.NotEnclClass(c));
3834 return syms.errSymbol;
3835 }
3836 //where
3837 private List<Type> pruneInterfaces(Type t) {
3838 ListBuffer<Type> result = new ListBuffer<>();
3839 for (Type t1 : types.interfaces(t)) {
3840 boolean shouldAdd = true;
3841 for (Type t2 : types.directSupertypes(t)) {
3842 if (t1 != t2 && !t2.hasTag(ERROR) && types.isSubtypeNoCapture(t2, t1)) {
3843 shouldAdd = false;
3844 }
3845 }
3846 if (shouldAdd) {
3847 result.append(t1);
3848 }
3849 }
3850 return result.toList();
3851 }
3852
3853 /**
3854 * Determine if an early instance field reference may appear in a constructor prologue.
3855 *
3856 * <p>
3857 * This is only allowed when:
3858 * - The field is being assigned a value (i.e., written but not read)
3859 * - The field is not inherited from a superclass
3860 * - The assignment is not within a lambda, because that would require
3861 * capturing 'this' which is not allowed prior to super().
3862 *
3863 * <p>
3864 * Note, this method doesn't catch all such scenarios, because this method
3865 * is invoked for symbol "x" only for "x = 42" but not for "this.x = 42".
3866 * We also don't verify that the field has no initializer, which is required.
3867 * To catch those cases, we rely on similar logic in Attr.checkAssignable().
3868 */
3869 private boolean isAllowedEarlyReference(DiagnosticPosition pos, Env<AttrContext> env, VarSymbol v) {
3870
3871 // Check assumptions
3872 Assert.check(env.info.ctorPrologue);
3873 Assert.check((v.flags_field & STATIC) == 0);
3874
3875 // The symbol must appear in the LHS of an assignment statement
3876 if (!(env.tree instanceof JCAssign assign))
3877 return false;
3878
3879 // The assignment statement must not be within a lambda
3880 if (env.info.isLambda)
3881 return false;
3882
3883 // Get the symbol's qualifier, if any
3884 JCExpression lhs = TreeInfo.skipParens(assign.lhs);
3885 JCExpression base;
3886 switch (lhs.getTag()) {
3887 case IDENT:
3888 base = null;
3889 break;
3890 case SELECT:
3891 JCFieldAccess select = (JCFieldAccess)lhs;
3892 base = select.selected;
3893 if (!TreeInfo.isExplicitThisReference(types, (ClassType)env.enclClass.type, base))
3894 return false;
3895 break;
3896 default:
3897 return false;
3898 }
3899
3900 // If an early reference, the field must not be declared in a superclass
3901 if (isEarlyReference(env, base, v) && v.owner != env.enclClass.sym)
3902 return false;
3903
3904 // The flexible constructors feature must be enabled
3905 preview.checkSourceLevel(pos, Feature.FLEXIBLE_CONSTRUCTORS);
3906
3907 // OK
3908 return true;
3909 }
3910
3911 /**
3912 * Determine if the variable appearance constitutes an early reference to the current class.
3913 *
3914 * <p>
3915 * This means the variable is an instance field of the current class and it appears
3916 * in an early initialization context of it (i.e., one of its constructor prologues).
3917 *
3918 * <p>
3919 * Such a reference is only allowed for assignments to non-initialized fields that are
3920 * not inherited from a superclass, though that is not enforced by this method.
3921 *
3922 * @param env The current environment
3923 * @param base Variable qualifier, if any, otherwise null
3924 * @param v The variable
3925 */
3926 public boolean isEarlyReference(Env<AttrContext> env, JCTree base, VarSymbol v) {
3927 return env.info.ctorPrologue &&
3928 (v.flags() & STATIC) == 0 &&
3929 v.owner.kind == TYP &&
3930 types.isSubtype(env.enclClass.type, v.owner.type) &&
3931 (base == null || TreeInfo.isExplicitThisReference(types, (ClassType)env.enclClass.type, base));
3932 }
3933
3934 /**
3935 * Resolve `c.this' for an enclosing class c that contains the
3936 * named member.
3937 * @param pos The position to use for error reporting.
3938 * @param env The environment current at the expression.
3939 * @param member The member that must be contained in the result.
3940 */
3941 Symbol resolveSelfContaining(DiagnosticPosition pos,
3942 Env<AttrContext> env,
3943 Symbol member,
3944 boolean isSuperCall) {
3945 Symbol sym = resolveSelfContainingInternal(env, member, isSuperCall);
3946 if (sym == null) {
3947 log.error(pos, Errors.EnclClassRequired(member));
3948 return syms.errSymbol;
3949 } else {
3950 return accessBase(sym, pos, env.enclClass.sym.type, sym.name, true);
3951 }
3952 }
3953
3954 boolean enclosingInstanceMissing(Env<AttrContext> env, Type type) {
3955 if (type.hasTag(CLASS) && type.getEnclosingType().hasTag(CLASS)) {
3956 Symbol encl = resolveSelfContainingInternal(env, type.tsym, false);
3957 return encl == null || encl.kind.isResolutionError();
3958 }
3959 return false;
3960 }
3961
3962 private Symbol resolveSelfContainingInternal(Env<AttrContext> env,
3963 Symbol member,
3964 boolean isSuperCall) {
3965 Name name = names._this;
3966 Env<AttrContext> env1 = isSuperCall ? env.outer : env;
3967 boolean staticOnly = false;
3968 if (env1 != null) {
3969 while (env1 != null && env1.outer != null) {
3970 if (isStatic(env1)) staticOnly = true;
3971 if (env1.enclClass.sym.isSubClass(member.owner.enclClass(), types)) {
3972 Symbol sym = env1.info.scope.findFirst(name);
3973 if (sym != null) {
3974 if (staticOnly) sym = new StaticError(sym);
3975 return sym;
3976 }
3977 }
3978 if ((env1.enclClass.sym.flags() & STATIC) != 0)
3979 staticOnly = true;
3980 env1 = env1.outer;
3981 }
3982 }
3983 return null;
3984 }
3985
3986 /**
3987 * Resolve an appropriate implicit this instance for t's container.
3988 * JLS 8.8.5.1 and 15.9.2
3989 */
3990 Type resolveImplicitThis(DiagnosticPosition pos, Env<AttrContext> env, Type t) {
3991 return resolveImplicitThis(pos, env, t, false);
3992 }
3993
3994 Type resolveImplicitThis(DiagnosticPosition pos, Env<AttrContext> env, Type t, boolean isSuperCall) {
3995 Type thisType = (t.tsym.owner.kind.matches(KindSelector.VAL_MTH)
3996 ? resolveSelf(pos, env, t.getEnclosingType().tsym, names._this)
3997 : resolveSelfContaining(pos, env, t.tsym, isSuperCall)).type;
3998 if (env.info.ctorPrologue && thisType.tsym == env.enclClass.sym) {
3999 log.error(pos, Errors.CantRefBeforeCtorCalled(names._this));
4000 }
4001 return thisType;
4002 }
4003
4004 /* ***************************************************************************
4005 * ResolveError classes, indicating error situations when accessing symbols
4006 ****************************************************************************/
4007
4008 //used by TransTypes when checking target type of synthetic cast
4009 public void logAccessErrorInternal(Env<AttrContext> env, JCTree tree, Type type) {
4010 AccessError error = new AccessError(env, env.enclClass.type, type.tsym);
4011 logResolveError(error, tree.pos(), env.enclClass.sym, env.enclClass.type, null, null, null);
4012 }
4013 //where
4014 private void logResolveError(ResolveError error,
4015 DiagnosticPosition pos,
4016 Symbol location,
4017 Type site,
4018 Name name,
4019 List<Type> argtypes,
4020 List<Type> typeargtypes) {
4021 JCDiagnostic d = error.getDiagnostic(JCDiagnostic.DiagnosticType.ERROR,
4022 pos, location, site, name, argtypes, typeargtypes);
4023 if (d != null) {
4024 d.setFlag(DiagnosticFlag.RESOLVE_ERROR);
4025 log.report(d);
4026 }
4027 }
4028
4029 private final LocalizedString noArgs = new LocalizedString("compiler.misc.no.args");
4030
4031 public Object methodArguments(List<Type> argtypes) {
4032 if (argtypes == null || argtypes.isEmpty()) {
4033 return noArgs;
4034 } else {
4035 ListBuffer<Object> diagArgs = new ListBuffer<>();
4036 for (Type t : argtypes) {
4037 if (t.hasTag(DEFERRED)) {
4038 diagArgs.append(((DeferredAttr.DeferredType)t).tree);
4039 } else {
4040 diagArgs.append(t);
4041 }
4042 }
4043 return diagArgs;
4044 }
4045 }
4046
4047 /** check if a type is a subtype of Serializable, if that is available.*/
4048 boolean isSerializable(Type t) {
4049 try {
4050 syms.serializableType.complete();
4051 }
4052 catch (CompletionFailure e) {
4053 return false;
4054 }
4055 return types.isSubtype(t, syms.serializableType);
4056 }
4057
4058 /**
4059 * Root class for resolution errors. Subclass of ResolveError
4060 * represent a different kinds of resolution error - as such they must
4061 * specify how they map into concrete compiler diagnostics.
4062 */
4063 abstract class ResolveError extends Symbol {
4064
4065 /** The name of the kind of error, for debugging only. */
4066 final String debugName;
4067
4068 ResolveError(Kind kind, String debugName) {
4069 super(kind, 0, null, null, null);
4070 this.debugName = debugName;
4071 }
4072
4073 @Override @DefinedBy(Api.LANGUAGE_MODEL)
4074 public <R, P> R accept(ElementVisitor<R, P> v, P p) {
4075 throw new AssertionError();
4076 }
4077
4078 @Override
4079 public String toString() {
4080 return debugName;
4081 }
4082
4083 @Override
4084 public boolean exists() {
4085 return false;
4086 }
4087
4088 @Override
4089 public boolean isStatic() {
4090 return false;
4091 }
4092
4093 /**
4094 * Create an external representation for this erroneous symbol to be
4095 * used during attribution - by default this returns the symbol of a
4096 * brand new error type which stores the original type found
4097 * during resolution.
4098 *
4099 * @param name the name used during resolution
4100 * @param location the location from which the symbol is accessed
4101 */
4102 protected Symbol access(Name name, TypeSymbol location) {
4103 return types.createErrorType(name, location, syms.errSymbol.type).tsym;
4104 }
4105
4106 /**
4107 * Create a diagnostic representing this resolution error.
4108 *
4109 * @param dkind The kind of the diagnostic to be created (e.g error).
4110 * @param pos The position to be used for error reporting.
4111 * @param site The original type from where the selection took place.
4112 * @param name The name of the symbol to be resolved.
4113 * @param argtypes The invocation's value arguments,
4114 * if we looked for a method.
4115 * @param typeargtypes The invocation's type arguments,
4116 * if we looked for a method.
4117 */
4118 abstract JCDiagnostic getDiagnostic(JCDiagnostic.DiagnosticType dkind,
4119 DiagnosticPosition pos,
4120 Symbol location,
4121 Type site,
4122 Name name,
4123 List<Type> argtypes,
4124 List<Type> typeargtypes);
4125 }
4126
4127 /**
4128 * This class is the root class of all resolution errors caused by
4129 * an invalid symbol being found during resolution.
4130 */
4131 abstract class InvalidSymbolError extends ResolveError {
4132
4133 /** The invalid symbol found during resolution */
4134 Symbol sym;
4135
4136 InvalidSymbolError(Kind kind, Symbol sym, String debugName) {
4137 super(kind, debugName);
4138 this.sym = sym;
4139 }
4140
4141 @Override
4142 public boolean exists() {
4143 return true;
4144 }
4145
4146 @Override
4147 public String toString() {
4148 return super.toString() + " wrongSym=" + sym;
4149 }
4150
4151 @Override
4152 public Symbol access(Name name, TypeSymbol location) {
4153 if (!sym.kind.isResolutionError() && sym.kind.matches(KindSelector.TYP))
4154 return types.createErrorType(name, location, sym.type).tsym;
4155 else
4156 return sym;
4157 }
4158 }
4159
4160 class BadRestrictedTypeError extends ResolveError {
4161 private final Name typeName;
4162 BadRestrictedTypeError(Name typeName) {
4163 super(Kind.BAD_RESTRICTED_TYPE, "bad var use");
4164 this.typeName = typeName;
4165 }
4166
4167 @Override
4168 JCDiagnostic getDiagnostic(DiagnosticType dkind, DiagnosticPosition pos, Symbol location, Type site, Name name, List<Type> argtypes, List<Type> typeargtypes) {
4169 return diags.create(dkind, log.currentSource(), pos, "illegal.ref.to.restricted.type", typeName);
4170 }
4171 }
4172
4173 /**
4174 * InvalidSymbolError error class indicating that a symbol matching a
4175 * given name does not exists in a given site.
4176 */
4177 class SymbolNotFoundError extends ResolveError {
4178
4179 SymbolNotFoundError(Kind kind) {
4180 this(kind, "symbol not found error");
4181 }
4182
4183 SymbolNotFoundError(Kind kind, String debugName) {
4184 super(kind, debugName);
4185 }
4186
4187 @Override
4188 JCDiagnostic getDiagnostic(JCDiagnostic.DiagnosticType dkind,
4189 DiagnosticPosition pos,
4190 Symbol location,
4191 Type site,
4192 Name name,
4193 List<Type> argtypes,
4194 List<Type> typeargtypes) {
4195 argtypes = argtypes == null ? List.nil() : argtypes;
4196 typeargtypes = typeargtypes == null ? List.nil() : typeargtypes;
4197 if (name == names.error)
4198 return null;
4199
4200 boolean hasLocation = false;
4201 if (location == null) {
4202 location = site.tsym;
4203 }
4204 if (!location.name.isEmpty()) {
4205 if (location.kind == PCK && !site.tsym.exists() && location.name != names.java) {
4206 return diags.create(dkind, log.currentSource(), pos,
4207 "doesnt.exist", location);
4208 }
4209 hasLocation = !location.name.equals(names._this) &&
4210 !location.name.equals(names._super);
4211 }
4212 boolean isConstructor = name == names.init;
4213 KindName kindname = isConstructor ? KindName.CONSTRUCTOR : kind.absentKind();
4214 Name idname = isConstructor ? site.tsym.name : name;
4215 String errKey = getErrorKey(kindname, typeargtypes.nonEmpty(), hasLocation);
4216 if (hasLocation) {
4217 return diags.create(dkind, log.currentSource(), pos,
4218 errKey, kindname, idname, //symbol kindname, name
4219 typeargtypes, args(argtypes), //type parameters and arguments (if any)
4220 getLocationDiag(location, site)); //location kindname, type
4221 }
4222 else {
4223 return diags.create(dkind, log.currentSource(), pos,
4224 errKey, kindname, idname, //symbol kindname, name
4225 typeargtypes, args(argtypes)); //type parameters and arguments (if any)
4226 }
4227 }
4228 //where
4229 private Object args(List<Type> args) {
4230 return args.isEmpty() ? args : methodArguments(args);
4231 }
4232
4233 private String getErrorKey(KindName kindname, boolean hasTypeArgs, boolean hasLocation) {
4234 String key = "cant.resolve";
4235 String suffix = hasLocation ? ".location" : "";
4236 switch (kindname) {
4237 case METHOD:
4238 case CONSTRUCTOR: {
4239 suffix += ".args";
4240 suffix += hasTypeArgs ? ".params" : "";
4241 }
4242 }
4243 return key + suffix;
4244 }
4245 private JCDiagnostic getLocationDiag(Symbol location, Type site) {
4246 if (location.kind == VAR) {
4247 return diags.fragment(Fragments.Location1(kindName(location),
4248 location,
4249 location.type));
4250 } else {
4251 return diags.fragment(Fragments.Location(typeKindName(site),
4252 site,
4253 null));
4254 }
4255 }
4256 }
4257
4258 /**
4259 * InvalidSymbolError error class indicating that a given symbol
4260 * (either a method, a constructor or an operand) is not applicable
4261 * given an actual arguments/type argument list.
4262 */
4263 class InapplicableSymbolError extends ResolveError {
4264
4265 protected MethodResolutionContext resolveContext;
4266
4267 InapplicableSymbolError(MethodResolutionContext context) {
4268 this(WRONG_MTH, "inapplicable symbol error", context);
4269 }
4270
4271 protected InapplicableSymbolError(Kind kind, String debugName, MethodResolutionContext context) {
4272 super(kind, debugName);
4273 this.resolveContext = context;
4274 }
4275
4276 @Override
4277 public String toString() {
4278 return super.toString();
4279 }
4280
4281 @Override
4282 public boolean exists() {
4283 return true;
4284 }
4285
4286 @Override
4287 JCDiagnostic getDiagnostic(JCDiagnostic.DiagnosticType dkind,
4288 DiagnosticPosition pos,
4289 Symbol location,
4290 Type site,
4291 Name name,
4292 List<Type> argtypes,
4293 List<Type> typeargtypes) {
4294 if (name == names.error)
4295 return null;
4296
4297 Pair<Symbol, JCDiagnostic> c = errCandidate();
4298 Symbol ws = c.fst.asMemberOf(site, types);
4299 UnaryOperator<JCDiagnostic> rewriter = compactMethodDiags ?
4300 d -> MethodResolutionDiagHelper.rewrite(diags, pos, log.currentSource(), dkind, c.snd) : null;
4301
4302 // If the problem is due to type arguments, then the method parameters aren't relevant,
4303 // so use the error message that omits them to avoid confusion.
4304 switch (c.snd.getCode()) {
4305 case "compiler.misc.wrong.number.type.args":
4306 case "compiler.misc.explicit.param.do.not.conform.to.bounds":
4307 return diags.create(dkind, log.currentSource(), pos,
4308 "cant.apply.symbol.noargs",
4309 rewriter,
4310 kindName(ws),
4311 ws.name == names.init ? ws.owner.name : ws.name,
4312 ws.owner.type,
4313 c.snd);
4314 default:
4315 // Avoid saying "constructor Array in class Array"
4316 if (ws.owner == syms.arrayClass && ws.name == names.init) {
4317 return diags.create(dkind, log.currentSource(), pos,
4318 "cant.apply.array.ctor",
4319 rewriter,
4320 methodArguments(ws.type.getParameterTypes()),
4321 methodArguments(argtypes),
4322 c.snd);
4323 }
4324 return diags.create(dkind, log.currentSource(), pos,
4325 "cant.apply.symbol",
4326 rewriter,
4327 kindName(ws),
4328 ws.name == names.init ? ws.owner.name : ws.name,
4329 methodArguments(ws.type.getParameterTypes()),
4330 methodArguments(argtypes),
4331 kindName(ws.owner),
4332 ws.owner.type,
4333 c.snd);
4334 }
4335 }
4336
4337 @Override
4338 public Symbol access(Name name, TypeSymbol location) {
4339 Pair<Symbol, JCDiagnostic> cand = errCandidate();
4340 TypeSymbol errSymbol = types.createErrorType(name, location, cand != null ? cand.fst.type : syms.errSymbol.type).tsym;
4341 if (cand != null) {
4342 attrRecover.wrongMethodSymbolCandidate(errSymbol, cand.fst, cand.snd);
4343 }
4344 return errSymbol;
4345 }
4346
4347 protected Pair<Symbol, JCDiagnostic> errCandidate() {
4348 Candidate bestSoFar = null;
4349 for (Candidate c : resolveContext.candidates) {
4350 if (c.isApplicable()) continue;
4351 bestSoFar = c;
4352 }
4353 Assert.checkNonNull(bestSoFar);
4354 return new Pair<>(bestSoFar.sym, bestSoFar.details);
4355 }
4356 }
4357
4358 /**
4359 * ResolveError error class indicating that a symbol (either methods, constructors or operand)
4360 * is not applicable given an actual arguments/type argument list.
4361 */
4362 class InapplicableSymbolsError extends InapplicableSymbolError {
4363
4364 InapplicableSymbolsError(MethodResolutionContext context) {
4365 super(WRONG_MTHS, "inapplicable symbols", context);
4366 }
4367
4368 @Override
4369 JCDiagnostic getDiagnostic(JCDiagnostic.DiagnosticType dkind,
4370 DiagnosticPosition pos,
4371 Symbol location,
4372 Type site,
4373 Name name,
4374 List<Type> argtypes,
4375 List<Type> typeargtypes) {
4376 Map<Symbol, JCDiagnostic> candidatesMap = mapCandidates();
4377 Map<Symbol, JCDiagnostic> filteredCandidates = compactMethodDiags ?
4378 filterCandidates(candidatesMap) :
4379 mapCandidates();
4380 if (filteredCandidates.isEmpty()) {
4381 filteredCandidates = candidatesMap;
4382 }
4383 boolean truncatedDiag = candidatesMap.size() != filteredCandidates.size();
4384 if (filteredCandidates.size() > 1) {
4385 JCDiagnostic err = diags.create(dkind,
4386 null,
4387 truncatedDiag ?
4388 EnumSet.of(DiagnosticFlag.COMPRESSED) :
4389 EnumSet.noneOf(DiagnosticFlag.class),
4390 log.currentSource(),
4391 pos,
4392 "cant.apply.symbols",
4393 name == names.init ? KindName.CONSTRUCTOR : kind.absentKind(),
4394 name == names.init ? site.tsym.name : name,
4395 methodArguments(argtypes));
4396 return new JCDiagnostic.MultilineDiagnostic(err, candidateDetails(filteredCandidates, site));
4397 } else if (filteredCandidates.size() == 1) {
4398 Map.Entry<Symbol, JCDiagnostic> _e =
4399 filteredCandidates.entrySet().iterator().next();
4400 final Pair<Symbol, JCDiagnostic> p = new Pair<>(_e.getKey(), _e.getValue());
4401 JCDiagnostic d = new InapplicableSymbolError(resolveContext) {
4402 @Override
4403 protected Pair<Symbol, JCDiagnostic> errCandidate() {
4404 return p;
4405 }
4406 }.getDiagnostic(dkind, pos,
4407 location, site, name, argtypes, typeargtypes);
4408 if (truncatedDiag) {
4409 d.setFlag(DiagnosticFlag.COMPRESSED);
4410 }
4411 return d;
4412 } else {
4413 return new SymbolNotFoundError(ABSENT_MTH).getDiagnostic(dkind, pos,
4414 location, site, name, argtypes, typeargtypes);
4415 }
4416 }
4417 //where
4418 private Map<Symbol, JCDiagnostic> mapCandidates() {
4419 MostSpecificMap candidates = new MostSpecificMap();
4420 for (Candidate c : resolveContext.candidates) {
4421 if (c.isApplicable()) continue;
4422 candidates.put(c);
4423 }
4424 return candidates;
4425 }
4426
4427 @SuppressWarnings("serial")
4428 private class MostSpecificMap extends LinkedHashMap<Symbol, JCDiagnostic> {
4429 private void put(Candidate c) {
4430 ListBuffer<Symbol> overridden = new ListBuffer<>();
4431 for (Symbol s : keySet()) {
4432 if (s == c.sym) {
4433 continue;
4434 }
4435 if (c.sym.overrides(s, (TypeSymbol)s.owner, types, false)) {
4436 overridden.add(s);
4437 } else if (s.overrides(c.sym, (TypeSymbol)c.sym.owner, types, false)) {
4438 return;
4439 }
4440 }
4441 for (Symbol s : overridden) {
4442 remove(s);
4443 }
4444 put(c.sym, c.details);
4445 }
4446 }
4447
4448 Map<Symbol, JCDiagnostic> filterCandidates(Map<Symbol, JCDiagnostic> candidatesMap) {
4449 Map<Symbol, JCDiagnostic> candidates = new LinkedHashMap<>();
4450 for (Map.Entry<Symbol, JCDiagnostic> _entry : candidatesMap.entrySet()) {
4451 JCDiagnostic d = _entry.getValue();
4452 if (!new Template(MethodCheckDiag.ARITY_MISMATCH.regex()).matches(d)) {
4453 candidates.put(_entry.getKey(), d);
4454 }
4455 }
4456 return candidates;
4457 }
4458
4459 private List<JCDiagnostic> candidateDetails(Map<Symbol, JCDiagnostic> candidatesMap, Type site) {
4460 List<JCDiagnostic> details = List.nil();
4461 for (Map.Entry<Symbol, JCDiagnostic> _entry : candidatesMap.entrySet()) {
4462 Symbol sym = _entry.getKey();
4463 JCDiagnostic detailDiag =
4464 diags.fragment(Fragments.InapplicableMethod(Kinds.kindName(sym),
4465 sym.location(site, types),
4466 sym.asMemberOf(site, types),
4467 _entry.getValue()));
4468 details = details.prepend(detailDiag);
4469 }
4470 //typically members are visited in reverse order (see Scope)
4471 //so we need to reverse the candidate list so that candidates
4472 //conform to source order
4473 return details;
4474 }
4475
4476 @Override
4477 protected Pair<Symbol, JCDiagnostic> errCandidate() {
4478 Map<Symbol, JCDiagnostic> candidatesMap = mapCandidates();
4479 Map<Symbol, JCDiagnostic> filteredCandidates = filterCandidates(candidatesMap);
4480 if (filteredCandidates.size() == 1) {
4481 return Pair.of(filteredCandidates.keySet().iterator().next(),
4482 filteredCandidates.values().iterator().next());
4483 }
4484 return null;
4485 }
4486 }
4487
4488 /**
4489 * DiamondError error class indicating that a constructor symbol is not applicable
4490 * given an actual arguments/type argument list using diamond inference.
4491 */
4492 class DiamondError extends InapplicableSymbolError {
4493
4494 Symbol sym;
4495
4496 public DiamondError(Symbol sym, MethodResolutionContext context) {
4497 super(sym.kind, "diamondError", context);
4498 this.sym = sym;
4499 }
4500
4501 JCDiagnostic getDetails() {
4502 return (sym.kind == WRONG_MTH) ?
4503 ((InapplicableSymbolError)sym.baseSymbol()).errCandidate().snd :
4504 null;
4505 }
4506
4507 @Override
4508 JCDiagnostic getDiagnostic(DiagnosticType dkind, DiagnosticPosition pos,
4509 Symbol location, Type site, Name name, List<Type> argtypes, List<Type> typeargtypes) {
4510 JCDiagnostic details = getDetails();
4511 if (details != null && compactMethodDiags) {
4512 JCDiagnostic simpleDiag =
4513 MethodResolutionDiagHelper.rewrite(diags, pos, log.currentSource(), dkind, details);
4514 if (simpleDiag != null) {
4515 return simpleDiag;
4516 }
4517 }
4518 String key = details == null ?
4519 "cant.apply.diamond" :
4520 "cant.apply.diamond.1";
4521 return diags.create(dkind, log.currentSource(), pos, key,
4522 Fragments.Diamond(site.tsym), details);
4523 }
4524 }
4525
4526 /**
4527 * An InvalidSymbolError error class indicating that a symbol is not
4528 * accessible from a given site
4529 */
4530 class AccessError extends InvalidSymbolError {
4531
4532 private Env<AttrContext> env;
4533 private Type site;
4534
4535 AccessError(Env<AttrContext> env, Type site, Symbol sym) {
4536 super(HIDDEN, sym, "access error");
4537 this.env = env;
4538 this.site = site;
4539 }
4540
4541 @Override
4542 public boolean exists() {
4543 return false;
4544 }
4545
4546 @Override
4547 JCDiagnostic getDiagnostic(JCDiagnostic.DiagnosticType dkind,
4548 DiagnosticPosition pos,
4549 Symbol location,
4550 Type site,
4551 Name name,
4552 List<Type> argtypes,
4553 List<Type> typeargtypes) {
4554 if (sym.name == names.init && sym.owner != site.tsym) {
4555 return new SymbolNotFoundError(ABSENT_MTH).getDiagnostic(dkind,
4556 pos, location, site, name, argtypes, typeargtypes);
4557 }
4558 else if ((sym.flags() & PUBLIC) != 0
4559 || (env != null && this.site != null
4560 && !isAccessible(env, this.site))) {
4561 if (sym.owner.kind == PCK) {
4562 return diags.create(dkind, log.currentSource(),
4563 pos, "not.def.access.package.cant.access",
4564 sym, sym.location(), inaccessiblePackageReason(env, sym.packge()));
4565 } else if ( sym.packge() != syms.rootPackage
4566 && !symbolPackageVisible(env, sym)) {
4567 return diags.create(dkind, log.currentSource(),
4568 pos, "not.def.access.class.intf.cant.access.reason",
4569 sym, sym.location(), sym.location().packge(),
4570 inaccessiblePackageReason(env, sym.packge()));
4571 } else {
4572 return diags.create(dkind, log.currentSource(),
4573 pos, "not.def.access.class.intf.cant.access",
4574 sym, sym.location());
4575 }
4576 }
4577 else if ((sym.flags() & (PRIVATE | PROTECTED)) != 0) {
4578 return diags.create(dkind, log.currentSource(),
4579 pos, "report.access", sym,
4580 asFlagSet(sym.flags() & (PRIVATE | PROTECTED)),
4581 sym.location());
4582 }
4583 else {
4584 return diags.create(dkind, log.currentSource(),
4585 pos, "not.def.public.cant.access", sym, sym.location());
4586 }
4587 }
4588
4589 private String toString(Type type) {
4590 StringBuilder sb = new StringBuilder();
4591 sb.append(type);
4592 if (type != null) {
4593 sb.append("[tsym:").append(type.tsym);
4594 if (type.tsym != null)
4595 sb.append("packge:").append(type.tsym.packge());
4596 sb.append("]");
4597 }
4598 return sb.toString();
4599 }
4600 }
4601
4602 class InvisibleSymbolError extends InvalidSymbolError {
4603
4604 private final Env<AttrContext> env;
4605 private final boolean suppressError;
4606
4607 InvisibleSymbolError(Env<AttrContext> env, boolean suppressError, Symbol sym) {
4608 super(HIDDEN, sym, "invisible class error");
4609 this.env = env;
4610 this.suppressError = suppressError;
4611 this.name = sym.name;
4612 }
4613
4614 @Override
4615 JCDiagnostic getDiagnostic(JCDiagnostic.DiagnosticType dkind,
4616 DiagnosticPosition pos,
4617 Symbol location,
4618 Type site,
4619 Name name,
4620 List<Type> argtypes,
4621 List<Type> typeargtypes) {
4622 if (suppressError)
4623 return null;
4624
4625 if (sym.kind == PCK) {
4626 JCDiagnostic details = inaccessiblePackageReason(env, sym.packge());
4627 return diags.create(dkind, log.currentSource(),
4628 pos, "package.not.visible", sym, details);
4629 }
4630
4631 JCDiagnostic details = inaccessiblePackageReason(env, sym.packge());
4632
4633 if (pos.getTree() != null) {
4634 Symbol o = sym;
4635 JCTree tree = pos.getTree();
4636
4637 while (o.kind != PCK && tree.hasTag(SELECT)) {
4638 o = o.owner;
4639 tree = ((JCFieldAccess) tree).selected;
4640 }
4641
4642 if (o.kind == PCK) {
4643 pos = tree.pos();
4644
4645 return diags.create(dkind, log.currentSource(),
4646 pos, "package.not.visible", o, details);
4647 }
4648 }
4649
4650 return diags.create(dkind, log.currentSource(),
4651 pos, "not.def.access.package.cant.access", sym, sym.packge(), details);
4652 }
4653 }
4654
4655 JCDiagnostic inaccessiblePackageReason(Env<AttrContext> env, PackageSymbol sym) {
4656 //no dependency:
4657 if (!env.toplevel.modle.readModules.contains(sym.modle)) {
4658 //does not read:
4659 if (sym.modle != syms.unnamedModule) {
4660 if (env.toplevel.modle != syms.unnamedModule) {
4661 return diags.fragment(Fragments.NotDefAccessDoesNotRead(env.toplevel.modle,
4662 sym,
4663 sym.modle));
4664 } else {
4665 return diags.fragment(Fragments.NotDefAccessDoesNotReadFromUnnamed(sym,
4666 sym.modle));
4667 }
4668 } else {
4669 return diags.fragment(Fragments.NotDefAccessDoesNotReadUnnamed(sym,
4670 env.toplevel.modle));
4671 }
4672 } else {
4673 if (sym.packge().modle.exports.stream().anyMatch(e -> e.packge == sym)) {
4674 //not exported to this module:
4675 if (env.toplevel.modle != syms.unnamedModule) {
4676 return diags.fragment(Fragments.NotDefAccessNotExportedToModule(sym,
4677 sym.modle,
4678 env.toplevel.modle));
4679 } else {
4680 return diags.fragment(Fragments.NotDefAccessNotExportedToModuleFromUnnamed(sym,
4681 sym.modle));
4682 }
4683 } else {
4684 //not exported:
4685 if (env.toplevel.modle != syms.unnamedModule) {
4686 return diags.fragment(Fragments.NotDefAccessNotExported(sym,
4687 sym.modle));
4688 } else {
4689 return diags.fragment(Fragments.NotDefAccessNotExportedFromUnnamed(sym,
4690 sym.modle));
4691 }
4692 }
4693 }
4694 }
4695
4696 /**
4697 * InvalidSymbolError error class indicating that an instance member
4698 * has erroneously been accessed from a static context.
4699 */
4700 class StaticError extends InvalidSymbolError {
4701
4702 StaticError(Symbol sym) {
4703 this(sym, "static error");
4704 }
4705
4706 StaticError(Symbol sym, String debugName) {
4707 super(STATICERR, sym, debugName);
4708 }
4709
4710 @Override
4711 JCDiagnostic getDiagnostic(JCDiagnostic.DiagnosticType dkind,
4712 DiagnosticPosition pos,
4713 Symbol location,
4714 Type site,
4715 Name name,
4716 List<Type> argtypes,
4717 List<Type> typeargtypes) {
4718 Symbol errSym = ((sym.kind == TYP && sym.type.hasTag(CLASS))
4719 ? types.erasure(sym.type).tsym
4720 : sym);
4721 return diags.create(dkind, log.currentSource(), pos,
4722 "non-static.cant.be.ref", kindName(sym), errSym);
4723 }
4724 }
4725
4726 /**
4727 * Specialization of {@link InvalidSymbolError} for illegal
4728 * early accesses within a constructor prologue.
4729 */
4730 class RefBeforeCtorCalledError extends StaticError {
4731
4732 RefBeforeCtorCalledError(Symbol sym) {
4733 super(sym, "prologue error");
4734 }
4735
4736 @Override
4737 JCDiagnostic getDiagnostic(JCDiagnostic.DiagnosticType dkind,
4738 DiagnosticPosition pos,
4739 Symbol location,
4740 Type site,
4741 Name name,
4742 List<Type> argtypes,
4743 List<Type> typeargtypes) {
4744 Symbol errSym = ((sym.kind == TYP && sym.type.hasTag(CLASS))
4745 ? types.erasure(sym.type).tsym
4746 : sym);
4747 return diags.create(dkind, log.currentSource(), pos,
4748 "cant.ref.before.ctor.called", errSym);
4749 }
4750 }
4751
4752 /**
4753 * InvalidSymbolError error class indicating that a pair of symbols
4754 * (either methods, constructors or operands) are ambiguous
4755 * given an actual arguments/type argument list.
4756 */
4757 class AmbiguityError extends ResolveError {
4758
4759 /** The other maximally specific symbol */
4760 List<Symbol> ambiguousSyms = List.nil();
4761
4762 @Override
4763 public boolean exists() {
4764 return true;
4765 }
4766
4767 AmbiguityError(Symbol sym1, Symbol sym2) {
4768 super(AMBIGUOUS, "ambiguity error");
4769 ambiguousSyms = flatten(sym2).appendList(flatten(sym1));
4770 }
4771
4772 private List<Symbol> flatten(Symbol sym) {
4773 if (sym.kind == AMBIGUOUS) {
4774 return ((AmbiguityError)sym.baseSymbol()).ambiguousSyms;
4775 } else {
4776 return List.of(sym);
4777 }
4778 }
4779
4780 AmbiguityError addAmbiguousSymbol(Symbol s) {
4781 ambiguousSyms = ambiguousSyms.prepend(s);
4782 return this;
4783 }
4784
4785 @Override
4786 JCDiagnostic getDiagnostic(JCDiagnostic.DiagnosticType dkind,
4787 DiagnosticPosition pos,
4788 Symbol location,
4789 Type site,
4790 Name name,
4791 List<Type> argtypes,
4792 List<Type> typeargtypes) {
4793 List<Symbol> diagSyms = ambiguousSyms.reverse();
4794 Symbol s1 = diagSyms.head;
4795 Symbol s2 = diagSyms.tail.head;
4796 Name sname = s1.name;
4797 if (sname == names.init) sname = s1.owner.name;
4798 return diags.create(dkind, log.currentSource(),
4799 pos, "ref.ambiguous", sname,
4800 kindName(s1),
4801 s1,
4802 s1.location(site, types),
4803 kindName(s2),
4804 s2,
4805 s2.location(site, types));
4806 }
4807
4808 /**
4809 * If multiple applicable methods are found during overload and none of them
4810 * is more specific than the others, attempt to merge their signatures.
4811 */
4812 Symbol mergeAbstracts(Type site) {
4813 List<Symbol> ambiguousInOrder = ambiguousSyms.reverse();
4814 return types.mergeAbstracts(ambiguousInOrder, site, true).orElse(this);
4815 }
4816
4817 @Override
4818 protected Symbol access(Name name, TypeSymbol location) {
4819 Symbol firstAmbiguity = ambiguousSyms.last();
4820 return firstAmbiguity.kind == TYP ?
4821 types.createErrorType(name, location, firstAmbiguity.type).tsym :
4822 firstAmbiguity;
4823 }
4824 }
4825
4826 class BadVarargsMethod extends ResolveError {
4827
4828 ResolveError delegatedError;
4829
4830 BadVarargsMethod(ResolveError delegatedError) {
4831 super(delegatedError.kind, "badVarargs");
4832 this.delegatedError = delegatedError;
4833 }
4834
4835 @Override
4836 public Symbol baseSymbol() {
4837 return delegatedError.baseSymbol();
4838 }
4839
4840 @Override
4841 protected Symbol access(Name name, TypeSymbol location) {
4842 return delegatedError.access(name, location);
4843 }
4844
4845 @Override
4846 public boolean exists() {
4847 return true;
4848 }
4849
4850 @Override
4851 JCDiagnostic getDiagnostic(DiagnosticType dkind, DiagnosticPosition pos, Symbol location, Type site, Name name, List<Type> argtypes, List<Type> typeargtypes) {
4852 return delegatedError.getDiagnostic(dkind, pos, location, site, name, argtypes, typeargtypes);
4853 }
4854 }
4855
4856 /**
4857 * BadMethodReferenceError error class indicating that a method reference symbol has been found,
4858 * but with the wrong staticness.
4859 */
4860 class BadMethodReferenceError extends StaticError {
4861
4862 boolean unboundLookup;
4863
4864 public BadMethodReferenceError(Symbol sym, boolean unboundLookup) {
4865 super(sym, "bad method ref error");
4866 this.unboundLookup = unboundLookup;
4867 }
4868
4869 @Override
4870 JCDiagnostic getDiagnostic(DiagnosticType dkind, DiagnosticPosition pos, Symbol location, Type site, Name name, List<Type> argtypes, List<Type> typeargtypes) {
4871 final String key;
4872 if (!unboundLookup) {
4873 key = "bad.static.method.in.bound.lookup";
4874 } else if (sym.isStatic()) {
4875 key = "bad.static.method.in.unbound.lookup";
4876 } else {
4877 key = "bad.instance.method.in.unbound.lookup";
4878 }
4879 return sym.kind.isResolutionError() ?
4880 ((ResolveError)sym).getDiagnostic(dkind, pos, location, site, name, argtypes, typeargtypes) :
4881 diags.create(dkind, log.currentSource(), pos, key, Kinds.kindName(sym), sym);
4882 }
4883 }
4884
4885 /**
4886 * BadConstructorReferenceError error class indicating that a constructor reference symbol has been found,
4887 * but pointing to a class for which an enclosing instance is not available.
4888 */
4889 class BadConstructorReferenceError extends InvalidSymbolError {
4890
4891 public BadConstructorReferenceError(Symbol sym) {
4892 super(MISSING_ENCL, sym, "BadConstructorReferenceError");
4893 }
4894
4895 @Override
4896 JCDiagnostic getDiagnostic(DiagnosticType dkind, DiagnosticPosition pos, Symbol location, Type site, Name name, List<Type> argtypes, List<Type> typeargtypes) {
4897 return diags.create(dkind, log.currentSource(), pos,
4898 "cant.access.inner.cls.constr", site.tsym.name, argtypes, site.getEnclosingType());
4899 }
4900 }
4901
4902 class BadClassFileError extends InvalidSymbolError {
4903
4904 private final CompletionFailure ex;
4905
4906 public BadClassFileError(CompletionFailure ex) {
4907 super(HIDDEN, ex.sym, "BadClassFileError");
4908 this.name = sym.name;
4909 this.ex = ex;
4910 }
4911
4912 @Override
4913 JCDiagnostic getDiagnostic(DiagnosticType dkind, DiagnosticPosition pos, Symbol location, Type site, Name name, List<Type> argtypes, List<Type> typeargtypes) {
4914 JCDiagnostic d = diags.create(dkind, log.currentSource(), pos,
4915 "cant.access", ex.sym, ex.getDetailValue());
4916
4917 d.setFlag(DiagnosticFlag.NON_DEFERRABLE);
4918 return d;
4919 }
4920
4921 }
4922
4923 /**
4924 * Helper class for method resolution diagnostic simplification.
4925 * Certain resolution diagnostic are rewritten as simpler diagnostic
4926 * where the enclosing resolution diagnostic (i.e. 'inapplicable method')
4927 * is stripped away, as it doesn't carry additional info. The logic
4928 * for matching a given diagnostic is given in terms of a template
4929 * hierarchy: a diagnostic template can be specified programmatically,
4930 * so that only certain diagnostics are matched. Each templete is then
4931 * associated with a rewriter object that carries out the task of rewtiting
4932 * the diagnostic to a simpler one.
4933 */
4934 static class MethodResolutionDiagHelper {
4935
4936 /**
4937 * A diagnostic rewriter transforms a method resolution diagnostic
4938 * into a simpler one
4939 */
4940 interface DiagnosticRewriter {
4941 JCDiagnostic rewriteDiagnostic(JCDiagnostic.Factory diags,
4942 DiagnosticPosition preferredPos, DiagnosticSource preferredSource,
4943 DiagnosticType preferredKind, JCDiagnostic d);
4944 }
4945
4946 /**
4947 * A diagnostic template is made up of two ingredients: (i) a regular
4948 * expression for matching a diagnostic key and (ii) a list of sub-templates
4949 * for matching diagnostic arguments.
4950 */
4951 static class Template {
4952
4953 /** regex used to match diag key */
4954 String regex;
4955
4956 /** templates used to match diagnostic args */
4957 Template[] subTemplates;
4958
4959 Template(String key, Template... subTemplates) {
4960 this.regex = key;
4961 this.subTemplates = subTemplates;
4962 }
4963
4964 /**
4965 * Returns true if the regex matches the diagnostic key and if
4966 * all diagnostic arguments are matches by corresponding sub-templates.
4967 */
4968 boolean matches(Object o) {
4969 JCDiagnostic d = (JCDiagnostic)o;
4970 Object[] args = d.getArgs();
4971 if (!d.getCode().matches(regex) ||
4972 subTemplates.length != d.getArgs().length) {
4973 return false;
4974 }
4975 for (int i = 0; i < args.length ; i++) {
4976 if (!subTemplates[i].matches(args[i])) {
4977 return false;
4978 }
4979 }
4980 return true;
4981 }
4982 }
4983
4984 /**
4985 * Common rewriter for all argument mismatch simplifications.
4986 */
4987 static class ArgMismatchRewriter implements DiagnosticRewriter {
4988
4989 /** the index of the subdiagnostic to be used as primary. */
4990 int causeIndex;
4991
4992 public ArgMismatchRewriter(int causeIndex) {
4993 this.causeIndex = causeIndex;
4994 }
4995
4996 @Override
4997 public JCDiagnostic rewriteDiagnostic(JCDiagnostic.Factory diags,
4998 DiagnosticPosition preferredPos, DiagnosticSource preferredSource,
4999 DiagnosticType preferredKind, JCDiagnostic d) {
5000 JCDiagnostic cause = (JCDiagnostic)d.getArgs()[causeIndex];
5001 DiagnosticPosition pos = d.getDiagnosticPosition();
5002 if (pos == null) {
5003 pos = preferredPos;
5004 }
5005 return diags.create(preferredKind, preferredSource, pos,
5006 "prob.found.req", cause);
5007 }
5008 }
5009
5010 /** a dummy template that match any diagnostic argument */
5011 static final Template skip = new Template("") {
5012 @Override
5013 boolean matches(Object d) {
5014 return true;
5015 }
5016 };
5017
5018 /** template for matching inference-free arguments mismatch failures */
5019 static final Template argMismatchTemplate = new Template(MethodCheckDiag.ARG_MISMATCH.regex(), skip);
5020
5021 /** template for matching inference related arguments mismatch failures */
5022 static final Template inferArgMismatchTemplate = new Template(MethodCheckDiag.ARG_MISMATCH.regex(), skip, skip) {
5023 @Override
5024 boolean matches(Object o) {
5025 if (!super.matches(o)) {
5026 return false;
5027 }
5028 JCDiagnostic d = (JCDiagnostic)o;
5029 @SuppressWarnings("unchecked")
5030 List<Type> tvars = (List<Type>)d.getArgs()[0];
5031 return !containsAny(d, tvars);
5032 }
5033
5034 BiPredicate<Object, List<Type>> containsPredicate = (o, ts) -> {
5035 if (o instanceof Type type) {
5036 return type.containsAny(ts);
5037 } else if (o instanceof JCDiagnostic diagnostic) {
5038 return containsAny(diagnostic, ts);
5039 } else {
5040 return false;
5041 }
5042 };
5043
5044 boolean containsAny(JCDiagnostic d, List<Type> ts) {
5045 return Stream.of(d.getArgs())
5046 .anyMatch(o -> containsPredicate.test(o, ts));
5047 }
5048 };
5049
5050 /** rewriter map used for method resolution simplification */
5051 static final Map<Template, DiagnosticRewriter> rewriters = new LinkedHashMap<>();
5052
5053 static {
5054 rewriters.put(argMismatchTemplate, new ArgMismatchRewriter(0));
5055 rewriters.put(inferArgMismatchTemplate, new ArgMismatchRewriter(1));
5056 }
5057
5058 /**
5059 * Main entry point for diagnostic rewriting - given a diagnostic, see if any templates matches it,
5060 * and rewrite it accordingly.
5061 */
5062 static JCDiagnostic rewrite(JCDiagnostic.Factory diags, DiagnosticPosition pos, DiagnosticSource source,
5063 DiagnosticType dkind, JCDiagnostic d) {
5064 for (Map.Entry<Template, DiagnosticRewriter> _entry : rewriters.entrySet()) {
5065 if (_entry.getKey().matches(d)) {
5066 JCDiagnostic simpleDiag =
5067 _entry.getValue().rewriteDiagnostic(diags, pos, source, dkind, d);
5068 simpleDiag.setFlag(DiagnosticFlag.COMPRESSED);
5069 return simpleDiag;
5070 }
5071 }
5072 return null;
5073 }
5074 }
5075
5076 enum MethodResolutionPhase {
5077 BASIC(false, false),
5078 BOX(true, false),
5079 VARARITY(true, true) {
5080 @Override
5081 public Symbol mergeResults(Symbol bestSoFar, Symbol sym) {
5082 //Check invariants (see {@code LookupHelper.shouldStop})
5083 Assert.check(bestSoFar.kind.isResolutionError() && bestSoFar.kind != AMBIGUOUS);
5084 if (!sym.kind.isResolutionError()) {
5085 //varargs resolution successful
5086 return sym;
5087 } else {
5088 //pick best error
5089 switch (bestSoFar.kind) {
5090 case WRONG_MTH:
5091 case WRONG_MTHS:
5092 //Override previous errors if they were caused by argument mismatch.
5093 //This generally means preferring current symbols - but we need to pay
5094 //attention to the fact that the varargs lookup returns 'less' candidates
5095 //than the previous rounds, and adjust that accordingly.
5096 switch (sym.kind) {
5097 case WRONG_MTH:
5098 //if the previous round matched more than one method, return that
5099 //result instead
5100 return bestSoFar.kind == WRONG_MTHS ?
5101 bestSoFar : sym;
5102 case ABSENT_MTH:
5103 //do not override erroneous symbol if the arity lookup did not
5104 //match any method
5105 return bestSoFar;
5106 case WRONG_MTHS:
5107 default:
5108 //safe to override
5109 return sym;
5110 }
5111 default:
5112 //otherwise, return first error
5113 return bestSoFar;
5114 }
5115 }
5116 }
5117 };
5118
5119 final boolean isBoxingRequired;
5120 final boolean isVarargsRequired;
5121
5122 MethodResolutionPhase(boolean isBoxingRequired, boolean isVarargsRequired) {
5123 this.isBoxingRequired = isBoxingRequired;
5124 this.isVarargsRequired = isVarargsRequired;
5125 }
5126
5127 public boolean isBoxingRequired() {
5128 return isBoxingRequired;
5129 }
5130
5131 public boolean isVarargsRequired() {
5132 return isVarargsRequired;
5133 }
5134
5135 public Symbol mergeResults(Symbol prev, Symbol sym) {
5136 return sym;
5137 }
5138 }
5139
5140 final List<MethodResolutionPhase> methodResolutionSteps = List.of(BASIC, BOX, VARARITY);
5141
5142 /**
5143 * A resolution context is used to keep track of intermediate results of
5144 * overload resolution, such as list of method that are not applicable
5145 * (used to generate more precise diagnostics) and so on. Resolution contexts
5146 * can be nested - this means that when each overload resolution routine should
5147 * work within the resolution context it created.
5148 */
5149 class MethodResolutionContext {
5150
5151 private List<Candidate> candidates = List.nil();
5152
5153 MethodResolutionPhase step = null;
5154
5155 MethodCheck methodCheck = resolveMethodCheck;
5156
5157 private boolean internalResolution = false;
5158 private DeferredAttr.AttrMode attrMode = DeferredAttr.AttrMode.SPECULATIVE;
5159
5160 void addInapplicableCandidate(Symbol sym, JCDiagnostic details) {
5161 Candidate c = new Candidate(currentResolutionContext.step, sym, details, null);
5162 candidates = candidates.append(c);
5163 }
5164
5165 void addApplicableCandidate(Symbol sym, Type mtype) {
5166 Candidate c = new Candidate(currentResolutionContext.step, sym, null, mtype);
5167 candidates = candidates.append(c);
5168 }
5169
5170 DeferredAttrContext deferredAttrContext(Symbol sym, InferenceContext inferenceContext, ResultInfo pendingResult, Warner warn) {
5171 DeferredAttrContext parent = (pendingResult == null)
5172 ? deferredAttr.emptyDeferredAttrContext
5173 : pendingResult.checkContext.deferredAttrContext();
5174 return deferredAttr.new DeferredAttrContext(attrMode, sym, step,
5175 inferenceContext, parent, warn);
5176 }
5177
5178 /**
5179 * This class represents an overload resolution candidate. There are two
5180 * kinds of candidates: applicable methods and inapplicable methods;
5181 * applicable methods have a pointer to the instantiated method type,
5182 * while inapplicable candidates contain further details about the
5183 * reason why the method has been considered inapplicable.
5184 */
5185 @SuppressWarnings("overrides")
5186 class Candidate {
5187
5188 final MethodResolutionPhase step;
5189 final Symbol sym;
5190 final JCDiagnostic details;
5191 final Type mtype;
5192
5193 private Candidate(MethodResolutionPhase step, Symbol sym, JCDiagnostic details, Type mtype) {
5194 this.step = step;
5195 this.sym = sym;
5196 this.details = details;
5197 this.mtype = mtype;
5198 }
5199
5200 boolean isApplicable() {
5201 return mtype != null;
5202 }
5203 }
5204
5205 DeferredAttr.AttrMode attrMode() {
5206 return attrMode;
5207 }
5208 }
5209
5210 MethodResolutionContext currentResolutionContext = null;
5211 }