1 /*
2 * Copyright (c) 1999, 2024, Oracle and/or its affiliates. All rights reserved.
3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
4 *
5 * This code is free software; you can redistribute it and/or modify it
6 * under the terms of the GNU General Public License version 2 only, as
7 * published by the Free Software Foundation. Oracle designates this
8 * particular file as subject to the "Classpath" exception as provided
9 * by Oracle in the LICENSE file that accompanied this code.
10 *
11 * This code is distributed in the hope that it will be useful, but WITHOUT
12 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
13 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
14 * version 2 for more details (a copy is included in the LICENSE file that
15 * accompanied this code).
16 *
17 * You should have received a copy of the GNU General Public License version
18 * 2 along with this work; if not, write to the Free Software Foundation,
19 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
20 *
21 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
22 * or visit www.oracle.com if you need additional information or have any
23 * questions.
24 */
25
26 package com.sun.tools.javac.comp;
27
28 import com.sun.tools.javac.api.Formattable.LocalizedString;
29 import com.sun.tools.javac.code.*;
30 import com.sun.tools.javac.code.Scope.WriteableScope;
31 import com.sun.tools.javac.code.Source.Feature;
32 import com.sun.tools.javac.code.Symbol.*;
33 import com.sun.tools.javac.code.Type.*;
34 import com.sun.tools.javac.comp.Attr.ResultInfo;
35 import com.sun.tools.javac.comp.Check.CheckContext;
36 import com.sun.tools.javac.comp.DeferredAttr.AttrMode;
37 import com.sun.tools.javac.comp.DeferredAttr.DeferredAttrContext;
38 import com.sun.tools.javac.comp.DeferredAttr.DeferredType;
39 import com.sun.tools.javac.comp.Resolve.MethodResolutionContext.Candidate;
40 import com.sun.tools.javac.comp.Resolve.MethodResolutionDiagHelper.Template;
41 import com.sun.tools.javac.comp.Resolve.ReferenceLookupResult.StaticKind;
42 import com.sun.tools.javac.jvm.*;
43 import com.sun.tools.javac.main.Option;
44 import com.sun.tools.javac.resources.CompilerProperties.Errors;
45 import com.sun.tools.javac.resources.CompilerProperties.Fragments;
46 import com.sun.tools.javac.resources.CompilerProperties.Warnings;
47 import com.sun.tools.javac.tree.*;
48 import com.sun.tools.javac.tree.JCTree.*;
49 import com.sun.tools.javac.tree.JCTree.JCMemberReference.ReferenceKind;
50 import com.sun.tools.javac.tree.JCTree.JCPolyExpression.*;
51 import com.sun.tools.javac.util.*;
52 import com.sun.tools.javac.util.DefinedBy.Api;
53 import com.sun.tools.javac.util.JCDiagnostic.DiagnosticFlag;
54 import com.sun.tools.javac.util.JCDiagnostic.DiagnosticPosition;
55 import com.sun.tools.javac.util.JCDiagnostic.DiagnosticType;
56
57 import java.util.Arrays;
58 import java.util.Collection;
59 import java.util.EnumSet;
60 import java.util.HashSet;
61 import java.util.Iterator;
62 import java.util.LinkedHashMap;
63 import java.util.Map;
64 import java.util.Set;
65 import java.util.function.BiFunction;
66 import java.util.function.BiPredicate;
67 import java.util.function.Function;
68 import java.util.function.Predicate;
69 import java.util.function.UnaryOperator;
70 import java.util.stream.Stream;
71 import java.util.stream.StreamSupport;
72
73 import javax.lang.model.element.ElementVisitor;
74
75 import static com.sun.tools.javac.code.Flags.*;
76 import static com.sun.tools.javac.code.Flags.BLOCK;
77 import static com.sun.tools.javac.code.Flags.STATIC;
78 import static com.sun.tools.javac.code.Kinds.*;
79 import static com.sun.tools.javac.code.Kinds.Kind.*;
80 import static com.sun.tools.javac.code.TypeTag.*;
81 import static com.sun.tools.javac.comp.Resolve.MethodResolutionPhase.*;
82 import static com.sun.tools.javac.main.Option.DOE;
83 import static com.sun.tools.javac.tree.JCTree.Tag.*;
84 import static com.sun.tools.javac.util.Iterators.createCompoundIterator;
85
86 /** Helper class for name resolution, used mostly by the attribution phase.
87 *
88 * <p><b>This is NOT part of any supported API.
89 * If you write code that depends on this, you do so at your own risk.
90 * This code and its internal interfaces are subject to change or
91 * deletion without notice.</b>
92 */
93 public class Resolve {
94 protected static final Context.Key<Resolve> resolveKey = new Context.Key<>();
95
96 Names names;
97 Log log;
98 Symtab syms;
99 Attr attr;
100 AttrRecover attrRecover;
101 DeferredAttr deferredAttr;
102 Check chk;
103 Infer infer;
104 Preview preview;
105 ClassFinder finder;
106 ModuleFinder moduleFinder;
107 Types types;
108 JCDiagnostic.Factory diags;
109 public final boolean allowModules;
110 public final boolean allowRecords;
111 private final boolean compactMethodDiags;
112 private final boolean allowLocalVariableTypeInference;
113 private final boolean allowYieldStatement;
114 private final boolean allowPrivateMembersInPermitsClause;
115 final EnumSet<VerboseResolutionMode> verboseResolutionMode;
116 final boolean dumpMethodReferenceSearchResults;
117 final boolean dumpStacktraceOnError;
118 private final LocalProxyVarsGen localProxyVarsGen;
119
120 WriteableScope polymorphicSignatureScope;
121
122 @SuppressWarnings("this-escape")
123 protected Resolve(Context context) {
124 context.put(resolveKey, this);
125 syms = Symtab.instance(context);
126
127 varNotFound = new SymbolNotFoundError(ABSENT_VAR);
128 methodNotFound = new SymbolNotFoundError(ABSENT_MTH);
129 typeNotFound = new SymbolNotFoundError(ABSENT_TYP);
130 referenceNotFound = ReferenceLookupResult.error(methodNotFound);
131
132 names = Names.instance(context);
133 log = Log.instance(context);
134 attr = Attr.instance(context);
135 attrRecover = AttrRecover.instance(context);
136 deferredAttr = DeferredAttr.instance(context);
137 chk = Check.instance(context);
138 infer = Infer.instance(context);
139 finder = ClassFinder.instance(context);
140 moduleFinder = ModuleFinder.instance(context);
141 types = Types.instance(context);
142 diags = JCDiagnostic.Factory.instance(context);
143 preview = Preview.instance(context);
144 Source source = Source.instance(context);
145 Options options = Options.instance(context);
146 compactMethodDiags = options.isSet(Option.XDIAGS, "compact") ||
147 options.isUnset(Option.XDIAGS) && options.isUnset("rawDiagnostics");
148 verboseResolutionMode = VerboseResolutionMode.getVerboseResolutionMode(options);
149 Target target = Target.instance(context);
150 allowLocalVariableTypeInference = Feature.LOCAL_VARIABLE_TYPE_INFERENCE.allowedInSource(source);
151 allowYieldStatement = Feature.SWITCH_EXPRESSION.allowedInSource(source);
152 allowPrivateMembersInPermitsClause = Feature.PRIVATE_MEMBERS_IN_PERMITS_CLAUSE.allowedInSource(source);
153 polymorphicSignatureScope = WriteableScope.create(syms.noSymbol);
154 allowModules = Feature.MODULES.allowedInSource(source);
155 allowRecords = Feature.RECORDS.allowedInSource(source);
156 dumpMethodReferenceSearchResults = options.isSet("debug.dumpMethodReferenceSearchResults");
157 dumpStacktraceOnError = options.isSet("dev") || options.isSet(DOE);
158 localProxyVarsGen = LocalProxyVarsGen.instance(context);
159 }
160
161 /** error symbols, which are returned when resolution fails
162 */
163 private final SymbolNotFoundError varNotFound;
164 private final SymbolNotFoundError methodNotFound;
165 private final SymbolNotFoundError typeNotFound;
166
167 /** empty reference lookup result */
168 private final ReferenceLookupResult referenceNotFound;
169
170 public static Resolve instance(Context context) {
171 Resolve instance = context.get(resolveKey);
172 if (instance == null)
173 instance = new Resolve(context);
174 return instance;
175 }
176
177 private static Symbol bestOf(Symbol s1,
178 Symbol s2) {
179 return s1.kind.betterThan(s2.kind) ? s1 : s2;
180 }
181
182 // <editor-fold defaultstate="collapsed" desc="Verbose resolution diagnostics support">
183 enum VerboseResolutionMode {
184 SUCCESS("success"),
185 FAILURE("failure"),
186 APPLICABLE("applicable"),
187 INAPPLICABLE("inapplicable"),
188 DEFERRED_INST("deferred-inference"),
189 PREDEF("predef"),
190 OBJECT_INIT("object-init"),
191 INTERNAL("internal");
192
193 final String opt;
194
195 private VerboseResolutionMode(String opt) {
196 this.opt = opt;
197 }
198
199 static EnumSet<VerboseResolutionMode> getVerboseResolutionMode(Options opts) {
200 String s = opts.get("debug.verboseResolution");
201 EnumSet<VerboseResolutionMode> res = EnumSet.noneOf(VerboseResolutionMode.class);
202 if (s == null) return res;
203 if (s.contains("all")) {
204 res = EnumSet.allOf(VerboseResolutionMode.class);
205 }
206 Collection<String> args = Arrays.asList(s.split(","));
207 for (VerboseResolutionMode mode : values()) {
208 if (args.contains(mode.opt)) {
209 res.add(mode);
210 } else if (args.contains("-" + mode.opt)) {
211 res.remove(mode);
212 }
213 }
214 return res;
215 }
216 }
217
218 void reportVerboseResolutionDiagnostic(DiagnosticPosition dpos, Name name, Type site,
219 List<Type> argtypes, List<Type> typeargtypes, Symbol bestSoFar) {
220 boolean success = !bestSoFar.kind.isResolutionError();
221
222 if (success && !verboseResolutionMode.contains(VerboseResolutionMode.SUCCESS)) {
223 return;
224 } else if (!success && !verboseResolutionMode.contains(VerboseResolutionMode.FAILURE)) {
225 return;
226 }
227
228 if (bestSoFar.name == names.init &&
229 bestSoFar.owner == syms.objectType.tsym &&
230 !verboseResolutionMode.contains(VerboseResolutionMode.OBJECT_INIT)) {
231 return; //skip diags for Object constructor resolution
232 } else if (site == syms.predefClass.type &&
233 !verboseResolutionMode.contains(VerboseResolutionMode.PREDEF)) {
234 return; //skip spurious diags for predef symbols (i.e. operators)
235 } else if (currentResolutionContext.internalResolution &&
236 !verboseResolutionMode.contains(VerboseResolutionMode.INTERNAL)) {
237 return;
238 }
239
240 int pos = 0;
241 int mostSpecificPos = -1;
242 ListBuffer<JCDiagnostic> subDiags = new ListBuffer<>();
243 for (Candidate c : currentResolutionContext.candidates) {
244 if (currentResolutionContext.step != c.step ||
245 (c.isApplicable() && !verboseResolutionMode.contains(VerboseResolutionMode.APPLICABLE)) ||
246 (!c.isApplicable() && !verboseResolutionMode.contains(VerboseResolutionMode.INAPPLICABLE))) {
247 continue;
248 } else {
249 subDiags.append(c.isApplicable() ?
250 getVerboseApplicableCandidateDiag(pos, c.sym, c.mtype) :
251 getVerboseInapplicableCandidateDiag(pos, c.sym, c.details));
252 if (c.sym == bestSoFar)
253 mostSpecificPos = pos;
254 pos++;
255 }
256 }
257 String key = success ? "verbose.resolve.multi" : "verbose.resolve.multi.1";
258 List<Type> argtypes2 = argtypes.map(deferredAttr.new RecoveryDeferredTypeMap(AttrMode.SPECULATIVE, bestSoFar, currentResolutionContext.step));
259 JCDiagnostic main = diags.note(log.currentSource(), dpos, key, name,
260 site.tsym, mostSpecificPos, currentResolutionContext.step,
261 methodArguments(argtypes2),
262 methodArguments(typeargtypes));
263 JCDiagnostic d = new JCDiagnostic.MultilineDiagnostic(main, subDiags.toList());
264 log.report(d);
265 }
266
267 JCDiagnostic getVerboseApplicableCandidateDiag(int pos, Symbol sym, Type inst) {
268 JCDiagnostic subDiag = null;
269 if (sym.type.hasTag(FORALL)) {
270 subDiag = diags.fragment(Fragments.PartialInstSig(inst));
271 }
272
273 String key = subDiag == null ?
274 "applicable.method.found" :
275 "applicable.method.found.1";
276
277 return diags.fragment(key, pos, sym, subDiag);
278 }
279
280 JCDiagnostic getVerboseInapplicableCandidateDiag(int pos, Symbol sym, JCDiagnostic subDiag) {
281 return diags.fragment(Fragments.NotApplicableMethodFound(pos, sym, subDiag));
282 }
283 // </editor-fold>
284
285 /* ************************************************************************
286 * Identifier resolution
287 *************************************************************************/
288
289 /** An environment is "static" if its static level is greater than
290 * the one of its outer environment
291 */
292 protected static boolean isStatic(Env<AttrContext> env) {
293 return env.outer != null && env.info.staticLevel > env.outer.info.staticLevel;
294 }
295
296 /** An environment is an "initializer" if it is a constructor or
297 * an instance initializer.
298 */
299 static boolean isInitializer(Env<AttrContext> env) {
300 Symbol owner = env.info.scope.owner;
301 return owner.isConstructor() ||
302 owner.owner.kind == TYP &&
303 (owner.kind == VAR ||
304 owner.kind == MTH && (owner.flags() & BLOCK) != 0) &&
305 (owner.flags() & STATIC) == 0;
306 }
307
308 /** Is class accessible in given environment?
309 * @param env The current environment.
310 * @param c The class whose accessibility is checked.
311 */
312 public boolean isAccessible(Env<AttrContext> env, TypeSymbol c) {
313 return isAccessible(env, c, false);
314 }
315
316 public boolean isAccessible(Env<AttrContext> env, TypeSymbol c, boolean checkInner) {
317
318 /* 15.9.5.1: Note that it is possible for the signature of the anonymous constructor
319 to refer to an inaccessible type
320 */
321 if (env.enclMethod != null && (env.enclMethod.mods.flags & ANONCONSTR) != 0)
322 return true;
323
324 if (env.info.visitingServiceImplementation &&
325 env.toplevel.modle == c.packge().modle) {
326 return true;
327 }
328
329 boolean isAccessible = false;
330 switch ((short)(c.flags() & AccessFlags)) {
331 case PRIVATE:
332 isAccessible =
333 env.enclClass.sym.outermostClass() ==
334 c.owner.outermostClass();
335 break;
336 case 0:
337 isAccessible =
338 env.toplevel.packge == c.owner // fast special case
339 ||
340 env.toplevel.packge == c.packge();
341 break;
342 default: // error recovery
343 isAccessible = true;
344 break;
345 case PUBLIC:
346 if (allowModules) {
347 ModuleSymbol currModule = env.toplevel.modle;
348 currModule.complete();
349 PackageSymbol p = c.packge();
350 isAccessible =
351 currModule == p.modle ||
352 currModule.visiblePackages.get(p.fullname) == p ||
353 p == syms.rootPackage ||
354 (p.modle == syms.unnamedModule && currModule.readModules.contains(p.modle));
355 } else {
356 isAccessible = true;
357 }
358 break;
359 case PROTECTED:
360 isAccessible =
361 env.toplevel.packge == c.owner // fast special case
362 ||
363 env.toplevel.packge == c.packge()
364 ||
365 isInnerSubClass(env.enclClass.sym, c.owner)
366 ||
367 env.info.allowProtectedAccess;
368 break;
369 }
370 return (checkInner == false || c.type.getEnclosingType() == Type.noType) ?
371 isAccessible :
372 isAccessible && isAccessible(env, c.type.getEnclosingType(), checkInner);
373 }
374 //where
375 /** Is given class a subclass of given base class, or an inner class
376 * of a subclass?
377 * Return null if no such class exists.
378 * @param c The class which is the subclass or is contained in it.
379 * @param base The base class
380 */
381 private boolean isInnerSubClass(ClassSymbol c, Symbol base) {
382 while (c != null && !c.isSubClass(base, types)) {
383 c = c.owner.enclClass();
384 }
385 return c != null;
386 }
387
388 boolean isAccessible(Env<AttrContext> env, Type t) {
389 return isAccessible(env, t, false);
390 }
391
392 boolean isAccessible(Env<AttrContext> env, Type t, boolean checkInner) {
393 if (t.hasTag(ARRAY)) {
394 return isAccessible(env, types.cvarUpperBound(types.elemtype(t)));
395 } else if (t.isUnion()) {
396 return StreamSupport.stream(((UnionClassType) t).getAlternativeTypes().spliterator(), false)
397 .allMatch(alternative -> isAccessible(env, alternative.tsym, checkInner));
398 } else {
399 return isAccessible(env, t.tsym, checkInner);
400 }
401 }
402
403 /** Is symbol accessible as a member of given type in given environment?
404 * @param env The current environment.
405 * @param site The type of which the tested symbol is regarded
406 * as a member.
407 * @param sym The symbol.
408 */
409 public boolean isAccessible(Env<AttrContext> env, Type site, Symbol sym) {
410 return isAccessible(env, site, sym, false);
411 }
412 public boolean isAccessible(Env<AttrContext> env, Type site, Symbol sym, boolean checkInner) {
413 if (sym.name == names.init && sym.owner != site.tsym) return false;
414
415 /* 15.9.5.1: Note that it is possible for the signature of the anonymous constructor
416 to refer to an inaccessible type
417 */
418 if (env.enclMethod != null && (env.enclMethod.mods.flags & ANONCONSTR) != 0)
419 return true;
420
421 if (env.info.visitingServiceImplementation &&
422 env.toplevel.modle == sym.packge().modle) {
423 return true;
424 }
425
426 ClassSymbol enclosingCsym = env.enclClass.sym;
427 try {
428 switch ((short)(sym.flags() & AccessFlags)) {
429 case PRIVATE:
430 return
431 (env.enclClass.sym == sym.owner // fast special case
432 ||
433 env.enclClass.sym.outermostClass() ==
434 sym.owner.outermostClass()
435 ||
436 privateMemberInPermitsClauseIfAllowed(env, sym))
437 &&
438 sym.isInheritedIn(site.tsym, types);
439 case 0:
440 return
441 (env.toplevel.packge == sym.owner.owner // fast special case
442 ||
443 env.toplevel.packge == sym.packge())
444 &&
445 isAccessible(env, site, checkInner)
446 &&
447 sym.isInheritedIn(site.tsym, types)
448 &&
449 notOverriddenIn(site, sym);
450 case PROTECTED:
451 return
452 (env.toplevel.packge == sym.owner.owner // fast special case
453 ||
454 env.toplevel.packge == sym.packge()
455 ||
456 isProtectedAccessible(sym, env.enclClass.sym, site)
457 ||
458 // OK to select instance method or field from 'super' or type name
459 // (but type names should be disallowed elsewhere!)
460 env.info.selectSuper && (sym.flags() & STATIC) == 0 && sym.kind != TYP)
461 &&
462 isAccessible(env, site, checkInner)
463 &&
464 notOverriddenIn(site, sym);
465 default: // this case includes erroneous combinations as well
466 return isAccessible(env, site, checkInner) && notOverriddenIn(site, sym);
467 }
468 } finally {
469 env.enclClass.sym = enclosingCsym;
470 }
471 }
472
473 private boolean privateMemberInPermitsClauseIfAllowed(Env<AttrContext> env, Symbol sym) {
474 return allowPrivateMembersInPermitsClause &&
475 env.info.isPermitsClause &&
476 ((JCClassDecl) env.tree).sym.outermostClass() == sym.owner.outermostClass();
477 }
478
479 //where
480 /* `sym' is accessible only if not overridden by
481 * another symbol which is a member of `site'
482 * (because, if it is overridden, `sym' is not strictly
483 * speaking a member of `site'). A polymorphic signature method
484 * cannot be overridden (e.g. MH.invokeExact(Object[])).
485 */
486 private boolean notOverriddenIn(Type site, Symbol sym) {
487 if (sym.kind != MTH || sym.isConstructor() || sym.isStatic())
488 return true;
489 else {
490 Symbol s2 = ((MethodSymbol)sym).implementation(site.tsym, types, true);
491 return (s2 == null || s2 == sym || sym.owner == s2.owner || (sym.owner.isInterface() && s2.owner == syms.objectType.tsym) ||
492 !types.isSubSignature(types.memberType(site, s2), types.memberType(site, sym)));
493 }
494 }
495 //where
496 /** Is given protected symbol accessible if it is selected from given site
497 * and the selection takes place in given class?
498 * @param sym The symbol with protected access
499 * @param c The class where the access takes place
500 * @param site The type of the qualifier
501 */
502 private
503 boolean isProtectedAccessible(Symbol sym, ClassSymbol c, Type site) {
504 Type newSite = site.hasTag(TYPEVAR) ? site.getUpperBound() : site;
505 while (c != null &&
506 !(c.isSubClass(sym.owner, types) &&
507 (c.flags() & INTERFACE) == 0 &&
508 // In JLS 2e 6.6.2.1, the subclass restriction applies
509 // only to instance fields and methods -- types are excluded
510 // regardless of whether they are declared 'static' or not.
511 ((sym.flags() & STATIC) != 0 || sym.kind == TYP || newSite.tsym.isSubClass(c, types))))
512 c = c.owner.enclClass();
513 return c != null;
514 }
515
516 /**
517 * Performs a recursive scan of a type looking for accessibility problems
518 * from current attribution environment
519 */
520 void checkAccessibleType(Env<AttrContext> env, Type t) {
521 accessibilityChecker.visit(t, env);
522 }
523
524 /**
525 * Accessibility type-visitor
526 */
527 Types.SimpleVisitor<Void, Env<AttrContext>> accessibilityChecker =
528 new Types.SimpleVisitor<Void, Env<AttrContext>>() {
529
530 void visit(List<Type> ts, Env<AttrContext> env) {
531 for (Type t : ts) {
532 visit(t, env);
533 }
534 }
535
536 public Void visitType(Type t, Env<AttrContext> env) {
537 return null;
538 }
539
540 @Override
541 public Void visitArrayType(ArrayType t, Env<AttrContext> env) {
542 visit(t.elemtype, env);
543 return null;
544 }
545
546 @Override
547 public Void visitClassType(ClassType t, Env<AttrContext> env) {
548 visit(t.getTypeArguments(), env);
549 if (!isAccessible(env, t, true)) {
550 accessBase(new AccessError(env, null, t.tsym), env.tree.pos(), env.enclClass.sym, t, t.tsym.name, true);
551 }
552 return null;
553 }
554
555 @Override
556 public Void visitWildcardType(WildcardType t, Env<AttrContext> env) {
557 visit(t.type, env);
558 return null;
559 }
560
561 @Override
562 public Void visitMethodType(MethodType t, Env<AttrContext> env) {
563 visit(t.getParameterTypes(), env);
564 visit(t.getReturnType(), env);
565 visit(t.getThrownTypes(), env);
566 return null;
567 }
568 };
569
570 /** Try to instantiate the type of a method so that it fits
571 * given type arguments and argument types. If successful, return
572 * the method's instantiated type, else return null.
573 * The instantiation will take into account an additional leading
574 * formal parameter if the method is an instance method seen as a member
575 * of an under determined site. In this case, we treat site as an additional
576 * parameter and the parameters of the class containing the method as
577 * additional type variables that get instantiated.
578 *
579 * @param env The current environment
580 * @param site The type of which the method is a member.
581 * @param m The method symbol.
582 * @param argtypes The invocation's given value arguments.
583 * @param typeargtypes The invocation's given type arguments.
584 * @param allowBoxing Allow boxing conversions of arguments.
585 * @param useVarargs Box trailing arguments into an array for varargs.
586 */
587 Type rawInstantiate(Env<AttrContext> env,
588 Type site,
589 Symbol m,
590 ResultInfo resultInfo,
591 List<Type> argtypes,
592 List<Type> typeargtypes,
593 boolean allowBoxing,
594 boolean useVarargs,
595 Warner warn) throws Infer.InferenceException {
596 Type mt = types.memberType(site, m);
597 // tvars is the list of formal type variables for which type arguments
598 // need to inferred.
599 List<Type> tvars = List.nil();
600 if (typeargtypes == null) typeargtypes = List.nil();
601 if (!mt.hasTag(FORALL) && typeargtypes.nonEmpty()) {
602 // This is not a polymorphic method, but typeargs are supplied
603 // which is fine, see JLS 15.12.2.1
604 } else if (mt.hasTag(FORALL) && typeargtypes.nonEmpty()) {
605 ForAll pmt = (ForAll) mt;
606 if (typeargtypes.length() != pmt.tvars.length())
607 // not enough args
608 throw new InapplicableMethodException(diags.fragment(Fragments.WrongNumberTypeArgs(Integer.toString(pmt.tvars.length()))), dumpStacktraceOnError);
609 // Check type arguments are within bounds
610 List<Type> formals = pmt.tvars;
611 List<Type> actuals = typeargtypes;
612 while (formals.nonEmpty() && actuals.nonEmpty()) {
613 List<Type> bounds = types.subst(types.getBounds((TypeVar)formals.head),
614 pmt.tvars, typeargtypes);
615 for (; bounds.nonEmpty(); bounds = bounds.tail) {
616 if (!types.isSubtypeUnchecked(actuals.head, bounds.head, warn)) {
617 throw new InapplicableMethodException(diags.fragment(Fragments.ExplicitParamDoNotConformToBounds(actuals.head, bounds)), dumpStacktraceOnError);
618 }
619 }
620 formals = formals.tail;
621 actuals = actuals.tail;
622 }
623 mt = types.subst(pmt.qtype, pmt.tvars, typeargtypes);
624 } else if (mt.hasTag(FORALL)) {
625 ForAll pmt = (ForAll) mt;
626 List<Type> tvars1 = types.newInstances(pmt.tvars);
627 tvars = tvars.appendList(tvars1);
628 mt = types.subst(pmt.qtype, pmt.tvars, tvars1);
629 }
630
631 // find out whether we need to go the slow route via infer
632 boolean instNeeded = tvars.tail != null; /*inlined: tvars.nonEmpty()*/
633 for (List<Type> l = argtypes;
634 l.tail != null/*inlined: l.nonEmpty()*/ && !instNeeded;
635 l = l.tail) {
636 if (l.head.hasTag(FORALL)) instNeeded = true;
637 }
638
639 if (instNeeded) {
640 return infer.instantiateMethod(env,
641 tvars,
642 (MethodType)mt,
643 resultInfo,
644 (MethodSymbol)m,
645 argtypes,
646 allowBoxing,
647 useVarargs,
648 currentResolutionContext,
649 warn);
650 }
651
652 DeferredAttr.DeferredAttrContext dc = currentResolutionContext.deferredAttrContext(m, infer.emptyContext, resultInfo, warn);
653 currentResolutionContext.methodCheck.argumentsAcceptable(env, dc,
654 argtypes, mt.getParameterTypes(), warn);
655 dc.complete();
656 return mt;
657 }
658
659 Type checkMethod(Env<AttrContext> env,
660 Type site,
661 Symbol m,
662 ResultInfo resultInfo,
663 List<Type> argtypes,
664 List<Type> typeargtypes,
665 Warner warn) {
666 MethodResolutionContext prevContext = currentResolutionContext;
667 try {
668 currentResolutionContext = new MethodResolutionContext();
669 currentResolutionContext.attrMode = (resultInfo.pt == Infer.anyPoly) ?
670 AttrMode.SPECULATIVE : DeferredAttr.AttrMode.CHECK;
671 if (env.tree.hasTag(JCTree.Tag.REFERENCE)) {
672 //method/constructor references need special check class
673 //to handle inference variables in 'argtypes' (might happen
674 //during an unsticking round)
675 currentResolutionContext.methodCheck =
676 new MethodReferenceCheck(resultInfo.checkContext.inferenceContext());
677 }
678 MethodResolutionPhase step = currentResolutionContext.step = env.info.pendingResolutionPhase;
679 return rawInstantiate(env, site, m, resultInfo, argtypes, typeargtypes,
680 step.isBoxingRequired(), step.isVarargsRequired(), warn);
681 }
682 finally {
683 currentResolutionContext = prevContext;
684 }
685 }
686
687 /** Same but returns null instead throwing a NoInstanceException
688 */
689 Type instantiate(Env<AttrContext> env,
690 Type site,
691 Symbol m,
692 ResultInfo resultInfo,
693 List<Type> argtypes,
694 List<Type> typeargtypes,
695 boolean allowBoxing,
696 boolean useVarargs,
697 Warner warn) {
698 try {
699 return rawInstantiate(env, site, m, resultInfo, argtypes, typeargtypes,
700 allowBoxing, useVarargs, warn);
701 } catch (InapplicableMethodException ex) {
702 return null;
703 }
704 }
705
706 /**
707 * This interface defines an entry point that should be used to perform a
708 * method check. A method check usually consist in determining as to whether
709 * a set of types (actuals) is compatible with another set of types (formals).
710 * Since the notion of compatibility can vary depending on the circumstances,
711 * this interfaces allows to easily add new pluggable method check routines.
712 */
713 interface MethodCheck {
714 /**
715 * Main method check routine. A method check usually consist in determining
716 * as to whether a set of types (actuals) is compatible with another set of
717 * types (formals). If an incompatibility is found, an unchecked exception
718 * is assumed to be thrown.
719 */
720 void argumentsAcceptable(Env<AttrContext> env,
721 DeferredAttrContext deferredAttrContext,
722 List<Type> argtypes,
723 List<Type> formals,
724 Warner warn);
725
726 /**
727 * Retrieve the method check object that will be used during a
728 * most specific check.
729 */
730 MethodCheck mostSpecificCheck(List<Type> actuals);
731 }
732
733 /**
734 * Helper enum defining all method check diagnostics (used by resolveMethodCheck).
735 */
736 enum MethodCheckDiag {
737 /**
738 * Actuals and formals differs in length.
739 */
740 ARITY_MISMATCH("arg.length.mismatch", "infer.arg.length.mismatch"),
741 /**
742 * An actual is incompatible with a formal.
743 */
744 ARG_MISMATCH("no.conforming.assignment.exists", "infer.no.conforming.assignment.exists"),
745 /**
746 * An actual is incompatible with the varargs element type.
747 */
748 VARARG_MISMATCH("varargs.argument.mismatch", "infer.varargs.argument.mismatch"),
749 /**
750 * The varargs element type is inaccessible.
751 */
752 INACCESSIBLE_VARARGS("inaccessible.varargs.type", "inaccessible.varargs.type");
753
754 final String basicKey;
755 final String inferKey;
756
757 MethodCheckDiag(String basicKey, String inferKey) {
758 this.basicKey = basicKey;
759 this.inferKey = inferKey;
760 }
761
762 String regex() {
763 return String.format("([a-z]*\\.)*(%s|%s)", basicKey, inferKey);
764 }
765 }
766
767 /**
768 * Dummy method check object. All methods are deemed applicable, regardless
769 * of their formal parameter types.
770 */
771 MethodCheck nilMethodCheck = new MethodCheck() {
772 public void argumentsAcceptable(Env<AttrContext> env, DeferredAttrContext deferredAttrContext, List<Type> argtypes, List<Type> formals, Warner warn) {
773 //do nothing - method always applicable regardless of actuals
774 }
775
776 public MethodCheck mostSpecificCheck(List<Type> actuals) {
777 return this;
778 }
779 };
780
781 /**
782 * Base class for 'real' method checks. The class defines the logic for
783 * iterating through formals and actuals and provides and entry point
784 * that can be used by subclasses in order to define the actual check logic.
785 */
786 abstract class AbstractMethodCheck implements MethodCheck {
787 @Override
788 public void argumentsAcceptable(final Env<AttrContext> env,
789 DeferredAttrContext deferredAttrContext,
790 List<Type> argtypes,
791 List<Type> formals,
792 Warner warn) {
793 //should we expand formals?
794 boolean useVarargs = deferredAttrContext.phase.isVarargsRequired();
795 JCTree callTree = treeForDiagnostics(env);
796 List<JCExpression> trees = TreeInfo.args(callTree);
797
798 //inference context used during this method check
799 InferenceContext inferenceContext = deferredAttrContext.inferenceContext;
800
801 Type varargsFormal = useVarargs ? formals.last() : null;
802
803 if (varargsFormal == null &&
804 argtypes.size() != formals.size()) {
805 reportMC(callTree, MethodCheckDiag.ARITY_MISMATCH, inferenceContext); // not enough args
806 }
807
808 while (argtypes.nonEmpty() && formals.head != varargsFormal) {
809 DiagnosticPosition pos = trees != null ? trees.head : null;
810 checkArg(pos, false, argtypes.head, formals.head, deferredAttrContext, warn);
811 argtypes = argtypes.tail;
812 formals = formals.tail;
813 trees = trees != null ? trees.tail : trees;
814 }
815
816 if (formals.head != varargsFormal) {
817 reportMC(callTree, MethodCheckDiag.ARITY_MISMATCH, inferenceContext); // not enough args
818 }
819
820 if (useVarargs) {
821 //note: if applicability check is triggered by most specific test,
822 //the last argument of a varargs is _not_ an array type (see JLS 15.12.2.5)
823 final Type elt = types.elemtype(varargsFormal);
824 while (argtypes.nonEmpty()) {
825 DiagnosticPosition pos = trees != null ? trees.head : null;
826 checkArg(pos, true, argtypes.head, elt, deferredAttrContext, warn);
827 argtypes = argtypes.tail;
828 trees = trees != null ? trees.tail : trees;
829 }
830 }
831 }
832
833 // where
834 private JCTree treeForDiagnostics(Env<AttrContext> env) {
835 return env.info.preferredTreeForDiagnostics != null ? env.info.preferredTreeForDiagnostics : env.tree;
836 }
837
838 /**
839 * Does the actual argument conforms to the corresponding formal?
840 */
841 abstract void checkArg(DiagnosticPosition pos, boolean varargs, Type actual, Type formal, DeferredAttrContext deferredAttrContext, Warner warn);
842
843 protected void reportMC(DiagnosticPosition pos, MethodCheckDiag diag, InferenceContext inferenceContext, Object... args) {
844 boolean inferDiag = inferenceContext != infer.emptyContext;
845 if (inferDiag && (!diag.inferKey.equals(diag.basicKey))) {
846 Object[] args2 = new Object[args.length + 1];
847 System.arraycopy(args, 0, args2, 1, args.length);
848 args2[0] = inferenceContext.inferenceVars();
849 args = args2;
850 }
851 String key = inferDiag ? diag.inferKey : diag.basicKey;
852 throw inferDiag ?
853 infer.error(diags.create(DiagnosticType.FRAGMENT, log.currentSource(), pos, key, args)) :
854 getMethodCheckFailure().setMessage(diags.create(DiagnosticType.FRAGMENT, log.currentSource(), pos, key, args));
855 }
856
857 /**
858 * To eliminate the overhead associated with allocating an exception object in such an
859 * hot execution path, we use flyweight pattern - and share the same exception instance
860 * across multiple method check failures.
861 */
862 class SharedInapplicableMethodException extends InapplicableMethodException {
863 private static final long serialVersionUID = 0;
864
865 SharedInapplicableMethodException() {
866 super(null, Resolve.this.dumpStacktraceOnError);
867 }
868
869 SharedInapplicableMethodException setMessage(JCDiagnostic details) {
870 this.diagnostic = details;
871 return this;
872 }
873 }
874
875 private SharedInapplicableMethodException methodCheckFailure;
876
877 public MethodCheck mostSpecificCheck(List<Type> actuals) {
878 return nilMethodCheck;
879 }
880
881 private SharedInapplicableMethodException getMethodCheckFailure() {
882 return methodCheckFailure == null ? methodCheckFailure = new SharedInapplicableMethodException() : methodCheckFailure;
883 }
884 }
885
886 /**
887 * Arity-based method check. A method is applicable if the number of actuals
888 * supplied conforms to the method signature.
889 */
890 MethodCheck arityMethodCheck = new AbstractMethodCheck() {
891 @Override
892 void checkArg(DiagnosticPosition pos, boolean varargs, Type actual, Type formal, DeferredAttrContext deferredAttrContext, Warner warn) {
893 //do nothing - actual always compatible to formals
894 }
895
896 @Override
897 public String toString() {
898 return "arityMethodCheck";
899 }
900 };
901
902 /**
903 * Main method applicability routine. Given a list of actual types A,
904 * a list of formal types F, determines whether the types in A are
905 * compatible (by method invocation conversion) with the types in F.
906 *
907 * Since this routine is shared between overload resolution and method
908 * type-inference, a (possibly empty) inference context is used to convert
909 * formal types to the corresponding 'undet' form ahead of a compatibility
910 * check so that constraints can be propagated and collected.
911 *
912 * Moreover, if one or more types in A is a deferred type, this routine uses
913 * DeferredAttr in order to perform deferred attribution. If one or more actual
914 * deferred types are stuck, they are placed in a queue and revisited later
915 * after the remainder of the arguments have been seen. If this is not sufficient
916 * to 'unstuck' the argument, a cyclic inference error is called out.
917 *
918 * A method check handler (see above) is used in order to report errors.
919 */
920 MethodCheck resolveMethodCheck = new AbstractMethodCheck() {
921
922 @Override
923 void checkArg(DiagnosticPosition pos, boolean varargs, Type actual, Type formal, DeferredAttrContext deferredAttrContext, Warner warn) {
924 ResultInfo mresult = methodCheckResult(varargs, formal, deferredAttrContext, warn);
925 mresult.check(pos, actual);
926 }
927
928 @Override
929 public void argumentsAcceptable(final Env<AttrContext> env,
930 DeferredAttrContext deferredAttrContext,
931 List<Type> argtypes,
932 List<Type> formals,
933 Warner warn) {
934 super.argumentsAcceptable(env, deferredAttrContext, argtypes, formals, warn);
935 // should we check varargs element type accessibility?
936 if (deferredAttrContext.phase.isVarargsRequired()) {
937 if (deferredAttrContext.mode == AttrMode.CHECK) {
938 varargsAccessible(env, types.elemtype(formals.last()), deferredAttrContext.inferenceContext);
939 }
940 }
941 }
942
943 /**
944 * Test that the runtime array element type corresponding to 't' is accessible. 't' should be the
945 * varargs element type of either the method invocation type signature (after inference completes)
946 * or the method declaration signature (before inference completes).
947 */
948 private void varargsAccessible(final Env<AttrContext> env, final Type t, final InferenceContext inferenceContext) {
949 if (inferenceContext.free(t)) {
950 inferenceContext.addFreeTypeListener(List.of(t),
951 solvedContext -> varargsAccessible(env, solvedContext.asInstType(t), solvedContext));
952 } else {
953 if (!isAccessible(env, types.erasure(t))) {
954 Symbol location = env.enclClass.sym;
955 reportMC(env.tree, MethodCheckDiag.INACCESSIBLE_VARARGS, inferenceContext, t, Kinds.kindName(location), location);
956 }
957 }
958 }
959
960 private ResultInfo methodCheckResult(final boolean varargsCheck, Type to,
961 final DeferredAttr.DeferredAttrContext deferredAttrContext, Warner rsWarner) {
962 CheckContext checkContext = new MethodCheckContext(!deferredAttrContext.phase.isBoxingRequired(), deferredAttrContext, rsWarner) {
963 MethodCheckDiag methodDiag = varargsCheck ?
964 MethodCheckDiag.VARARG_MISMATCH : MethodCheckDiag.ARG_MISMATCH;
965
966 @Override
967 public void report(DiagnosticPosition pos, JCDiagnostic details) {
968 reportMC(pos, methodDiag, deferredAttrContext.inferenceContext, details);
969 }
970 };
971 return new MethodResultInfo(to, checkContext);
972 }
973
974 @Override
975 public MethodCheck mostSpecificCheck(List<Type> actuals) {
976 return new MostSpecificCheck(actuals);
977 }
978
979 @Override
980 public String toString() {
981 return "resolveMethodCheck";
982 }
983 };
984
985 /**
986 * This class handles method reference applicability checks; since during
987 * these checks it's sometime possible to have inference variables on
988 * the actual argument types list, the method applicability check must be
989 * extended so that inference variables are 'opened' as needed.
990 */
991 class MethodReferenceCheck extends AbstractMethodCheck {
992
993 InferenceContext pendingInferenceContext;
994
995 MethodReferenceCheck(InferenceContext pendingInferenceContext) {
996 this.pendingInferenceContext = pendingInferenceContext;
997 }
998
999 @Override
1000 void checkArg(DiagnosticPosition pos, boolean varargs, Type actual, Type formal, DeferredAttrContext deferredAttrContext, Warner warn) {
1001 ResultInfo mresult = methodCheckResult(varargs, formal, deferredAttrContext, warn);
1002 mresult.check(pos, actual);
1003 }
1004
1005 private ResultInfo methodCheckResult(final boolean varargsCheck, Type to,
1006 final DeferredAttr.DeferredAttrContext deferredAttrContext, Warner rsWarner) {
1007 CheckContext checkContext = new MethodCheckContext(!deferredAttrContext.phase.isBoxingRequired(), deferredAttrContext, rsWarner) {
1008 MethodCheckDiag methodDiag = varargsCheck ?
1009 MethodCheckDiag.VARARG_MISMATCH : MethodCheckDiag.ARG_MISMATCH;
1010
1011 @Override
1012 public boolean compatible(Type found, Type req, Warner warn) {
1013 found = pendingInferenceContext.asUndetVar(found);
1014 if (found.hasTag(UNDETVAR) && req.isPrimitive()) {
1015 req = types.boxedClass(req).type;
1016 }
1017 return super.compatible(found, req, warn);
1018 }
1019
1020 @Override
1021 public void report(DiagnosticPosition pos, JCDiagnostic details) {
1022 reportMC(pos, methodDiag, deferredAttrContext.inferenceContext, details);
1023 }
1024 };
1025 return new MethodResultInfo(to, checkContext);
1026 }
1027
1028 @Override
1029 public MethodCheck mostSpecificCheck(List<Type> actuals) {
1030 return new MostSpecificCheck(actuals);
1031 }
1032
1033 @Override
1034 public String toString() {
1035 return "MethodReferenceCheck";
1036 }
1037 }
1038
1039 /**
1040 * Check context to be used during method applicability checks. A method check
1041 * context might contain inference variables.
1042 */
1043 abstract class MethodCheckContext implements CheckContext {
1044
1045 boolean strict;
1046 DeferredAttrContext deferredAttrContext;
1047 Warner rsWarner;
1048
1049 public MethodCheckContext(boolean strict, DeferredAttrContext deferredAttrContext, Warner rsWarner) {
1050 this.strict = strict;
1051 this.deferredAttrContext = deferredAttrContext;
1052 this.rsWarner = rsWarner;
1053 }
1054
1055 public boolean compatible(Type found, Type req, Warner warn) {
1056 InferenceContext inferenceContext = deferredAttrContext.inferenceContext;
1057 return strict ?
1058 types.isSubtypeUnchecked(inferenceContext.asUndetVar(found), inferenceContext.asUndetVar(req), warn) :
1059 types.isConvertible(inferenceContext.asUndetVar(found), inferenceContext.asUndetVar(req), warn);
1060 }
1061
1062 public void report(DiagnosticPosition pos, JCDiagnostic details) {
1063 throw new InapplicableMethodException(details, Resolve.this.dumpStacktraceOnError);
1064 }
1065
1066 public Warner checkWarner(DiagnosticPosition pos, Type found, Type req) {
1067 return rsWarner;
1068 }
1069
1070 public InferenceContext inferenceContext() {
1071 return deferredAttrContext.inferenceContext;
1072 }
1073
1074 public DeferredAttrContext deferredAttrContext() {
1075 return deferredAttrContext;
1076 }
1077
1078 @Override
1079 public String toString() {
1080 return "MethodCheckContext";
1081 }
1082 }
1083
1084 /**
1085 * ResultInfo class to be used during method applicability checks. Check
1086 * for deferred types goes through special path.
1087 */
1088 class MethodResultInfo extends ResultInfo {
1089
1090 public MethodResultInfo(Type pt, CheckContext checkContext) {
1091 attr.super(KindSelector.VAL, pt, checkContext);
1092 }
1093
1094 @Override
1095 protected Type check(DiagnosticPosition pos, Type found) {
1096 if (found.hasTag(DEFERRED)) {
1097 DeferredType dt = (DeferredType)found;
1098 return dt.check(this);
1099 } else {
1100 Type uResult = U(found);
1101 Type capturedType = pos == null || pos.getTree() == null ?
1102 types.capture(uResult) :
1103 checkContext.inferenceContext()
1104 .cachedCapture(pos.getTree(), uResult, true);
1105 return super.check(pos, chk.checkNonVoid(pos, capturedType));
1106 }
1107 }
1108
1109 /**
1110 * javac has a long-standing 'simplification' (see 6391995):
1111 * given an actual argument type, the method check is performed
1112 * on its upper bound. This leads to inconsistencies when an
1113 * argument type is checked against itself. For example, given
1114 * a type-variable T, it is not true that {@code U(T) <: T},
1115 * so we need to guard against that.
1116 */
1117 private Type U(Type found) {
1118 return found == pt ?
1119 found : types.cvarUpperBound(found);
1120 }
1121
1122 @Override
1123 protected MethodResultInfo dup(Type newPt) {
1124 return new MethodResultInfo(newPt, checkContext);
1125 }
1126
1127 @Override
1128 protected ResultInfo dup(CheckContext newContext) {
1129 return new MethodResultInfo(pt, newContext);
1130 }
1131
1132 @Override
1133 protected ResultInfo dup(Type newPt, CheckContext newContext) {
1134 return new MethodResultInfo(newPt, newContext);
1135 }
1136 }
1137
1138 /**
1139 * Most specific method applicability routine. Given a list of actual types A,
1140 * a list of formal types F1, and a list of formal types F2, the routine determines
1141 * as to whether the types in F1 can be considered more specific than those in F2 w.r.t.
1142 * argument types A.
1143 */
1144 class MostSpecificCheck implements MethodCheck {
1145
1146 List<Type> actuals;
1147
1148 MostSpecificCheck(List<Type> actuals) {
1149 this.actuals = actuals;
1150 }
1151
1152 @Override
1153 public void argumentsAcceptable(final Env<AttrContext> env,
1154 DeferredAttrContext deferredAttrContext,
1155 List<Type> formals1,
1156 List<Type> formals2,
1157 Warner warn) {
1158 formals2 = adjustArgs(formals2, deferredAttrContext.msym, formals1.length(), deferredAttrContext.phase.isVarargsRequired());
1159 while (formals2.nonEmpty()) {
1160 ResultInfo mresult = methodCheckResult(formals2.head, deferredAttrContext, warn, actuals.head);
1161 mresult.check(null, formals1.head);
1162 formals1 = formals1.tail;
1163 formals2 = formals2.tail;
1164 actuals = actuals.isEmpty() ? actuals : actuals.tail;
1165 }
1166 }
1167
1168 /**
1169 * Create a method check context to be used during the most specific applicability check
1170 */
1171 ResultInfo methodCheckResult(Type to, DeferredAttr.DeferredAttrContext deferredAttrContext,
1172 Warner rsWarner, Type actual) {
1173 return attr.new ResultInfo(KindSelector.VAL, to,
1174 new MostSpecificCheckContext(deferredAttrContext, rsWarner, actual));
1175 }
1176
1177 /**
1178 * Subclass of method check context class that implements most specific
1179 * method conversion. If the actual type under analysis is a deferred type
1180 * a full blown structural analysis is carried out.
1181 */
1182 class MostSpecificCheckContext extends MethodCheckContext {
1183
1184 Type actual;
1185
1186 public MostSpecificCheckContext(DeferredAttrContext deferredAttrContext, Warner rsWarner, Type actual) {
1187 super(true, deferredAttrContext, rsWarner);
1188 this.actual = actual;
1189 }
1190
1191 public boolean compatible(Type found, Type req, Warner warn) {
1192 if (unrelatedFunctionalInterfaces(found, req) &&
1193 (actual != null && actual.getTag() == DEFERRED)) {
1194 DeferredType dt = (DeferredType) actual;
1195 JCTree speculativeTree = dt.speculativeTree(deferredAttrContext);
1196 if (speculativeTree != deferredAttr.stuckTree) {
1197 return functionalInterfaceMostSpecific(found, req, speculativeTree);
1198 }
1199 }
1200 return compatibleBySubtyping(found, req);
1201 }
1202
1203 private boolean compatibleBySubtyping(Type found, Type req) {
1204 if (!strict && found.isPrimitive() != req.isPrimitive()) {
1205 found = found.isPrimitive() ? types.boxedClass(found).type : types.unboxedType(found);
1206 }
1207 return types.isSubtypeNoCapture(found, deferredAttrContext.inferenceContext.asUndetVar(req));
1208 }
1209
1210 /** Whether {@code t} and {@code s} are unrelated functional interface types. */
1211 private boolean unrelatedFunctionalInterfaces(Type t, Type s) {
1212 return types.isFunctionalInterface(t.tsym) &&
1213 types.isFunctionalInterface(s.tsym) &&
1214 unrelatedInterfaces(t, s);
1215 }
1216
1217 /** Whether {@code t} and {@code s} are unrelated interface types; recurs on intersections. **/
1218 private boolean unrelatedInterfaces(Type t, Type s) {
1219 if (t.isCompound()) {
1220 for (Type ti : types.interfaces(t)) {
1221 if (!unrelatedInterfaces(ti, s)) {
1222 return false;
1223 }
1224 }
1225 return true;
1226 } else if (s.isCompound()) {
1227 for (Type si : types.interfaces(s)) {
1228 if (!unrelatedInterfaces(t, si)) {
1229 return false;
1230 }
1231 }
1232 return true;
1233 } else {
1234 return types.asSuper(t, s.tsym) == null && types.asSuper(s, t.tsym) == null;
1235 }
1236 }
1237
1238 /** Parameters {@code t} and {@code s} are unrelated functional interface types. */
1239 private boolean functionalInterfaceMostSpecific(Type t, Type s, JCTree tree) {
1240 Type tDesc;
1241 Type tDescNoCapture;
1242 Type sDesc;
1243 try {
1244 tDesc = types.findDescriptorType(types.capture(t));
1245 tDescNoCapture = types.findDescriptorType(t);
1246 sDesc = types.findDescriptorType(s);
1247 } catch (Types.FunctionDescriptorLookupError ex) {
1248 // don't report, a more meaningful error should be reported upstream
1249 return false;
1250 }
1251 final List<Type> tTypeParams = tDesc.getTypeArguments();
1252 final List<Type> tTypeParamsNoCapture = tDescNoCapture.getTypeArguments();
1253 final List<Type> sTypeParams = sDesc.getTypeArguments();
1254
1255 // compare type parameters
1256 if (tDesc.hasTag(FORALL) && !types.hasSameBounds((ForAll) tDesc, (ForAll) tDescNoCapture)) {
1257 return false;
1258 }
1259 // can't use Types.hasSameBounds on sDesc because bounds may have ivars
1260 List<Type> tIter = tTypeParams;
1261 List<Type> sIter = sTypeParams;
1262 while (tIter.nonEmpty() && sIter.nonEmpty()) {
1263 Type tBound = tIter.head.getUpperBound();
1264 Type sBound = types.subst(sIter.head.getUpperBound(), sTypeParams, tTypeParams);
1265 if (tBound.containsAny(tTypeParams) && inferenceContext().free(sBound)) {
1266 return false;
1267 }
1268 if (!types.isSameType(tBound, inferenceContext().asUndetVar(sBound))) {
1269 return false;
1270 }
1271 tIter = tIter.tail;
1272 sIter = sIter.tail;
1273 }
1274 if (!tIter.isEmpty() || !sIter.isEmpty()) {
1275 return false;
1276 }
1277
1278 // compare parameters
1279 List<Type> tParams = tDesc.getParameterTypes();
1280 List<Type> tParamsNoCapture = tDescNoCapture.getParameterTypes();
1281 List<Type> sParams = sDesc.getParameterTypes();
1282 while (tParams.nonEmpty() && tParamsNoCapture.nonEmpty() && sParams.nonEmpty()) {
1283 Type tParam = tParams.head;
1284 Type tParamNoCapture = types.subst(tParamsNoCapture.head, tTypeParamsNoCapture, tTypeParams);
1285 Type sParam = types.subst(sParams.head, sTypeParams, tTypeParams);
1286 if (tParam.containsAny(tTypeParams) && inferenceContext().free(sParam)) {
1287 return false;
1288 }
1289 if (!types.isSubtype(inferenceContext().asUndetVar(sParam), tParam)) {
1290 return false;
1291 }
1292 if (!types.isSameType(tParamNoCapture, inferenceContext().asUndetVar(sParam))) {
1293 return false;
1294 }
1295 tParams = tParams.tail;
1296 tParamsNoCapture = tParamsNoCapture.tail;
1297 sParams = sParams.tail;
1298 }
1299 if (!tParams.isEmpty() || !tParamsNoCapture.isEmpty() || !sParams.isEmpty()) {
1300 return false;
1301 }
1302
1303 // compare returns
1304 Type tRet = tDesc.getReturnType();
1305 Type sRet = types.subst(sDesc.getReturnType(), sTypeParams, tTypeParams);
1306 if (tRet.containsAny(tTypeParams) && inferenceContext().free(sRet)) {
1307 return false;
1308 }
1309 MostSpecificFunctionReturnChecker msc = new MostSpecificFunctionReturnChecker(tRet, sRet);
1310 msc.scan(tree);
1311 return msc.result;
1312 }
1313
1314 /**
1315 * Tests whether one functional interface type can be considered more specific
1316 * than another unrelated functional interface type for the scanned expression.
1317 */
1318 class MostSpecificFunctionReturnChecker extends DeferredAttr.PolyScanner {
1319
1320 final Type tRet;
1321 final Type sRet;
1322 boolean result;
1323
1324 /** Parameters {@code t} and {@code s} are unrelated functional interface types. */
1325 MostSpecificFunctionReturnChecker(Type tRet, Type sRet) {
1326 this.tRet = tRet;
1327 this.sRet = sRet;
1328 result = true;
1329 }
1330
1331 @Override
1332 void skip(JCTree tree) {
1333 result = false;
1334 }
1335
1336 @Override
1337 public void visitConditional(JCConditional tree) {
1338 scan(asExpr(tree.truepart));
1339 scan(asExpr(tree.falsepart));
1340 }
1341
1342 @Override
1343 public void visitReference(JCMemberReference tree) {
1344 if (sRet.hasTag(VOID)) {
1345 // do nothing
1346 } else if (tRet.hasTag(VOID)) {
1347 result = false;
1348 } else if (tRet.isPrimitive() != sRet.isPrimitive()) {
1349 boolean retValIsPrimitive =
1350 tree.refPolyKind == PolyKind.STANDALONE &&
1351 tree.sym.type.getReturnType().isPrimitive();
1352 result &= (retValIsPrimitive == tRet.isPrimitive()) &&
1353 (retValIsPrimitive != sRet.isPrimitive());
1354 } else {
1355 result &= compatibleBySubtyping(tRet, sRet);
1356 }
1357 }
1358
1359 @Override
1360 public void visitParens(JCParens tree) {
1361 scan(asExpr(tree.expr));
1362 }
1363
1364 @Override
1365 public void visitLambda(JCLambda tree) {
1366 if (sRet.hasTag(VOID)) {
1367 // do nothing
1368 } else if (tRet.hasTag(VOID)) {
1369 result = false;
1370 } else {
1371 List<JCExpression> lambdaResults = lambdaResults(tree);
1372 if (!lambdaResults.isEmpty() && unrelatedFunctionalInterfaces(tRet, sRet)) {
1373 for (JCExpression expr : lambdaResults) {
1374 result &= functionalInterfaceMostSpecific(tRet, sRet, expr);
1375 }
1376 } else if (!lambdaResults.isEmpty() && tRet.isPrimitive() != sRet.isPrimitive()) {
1377 for (JCExpression expr : lambdaResults) {
1378 boolean retValIsPrimitive = expr.isStandalone() && expr.type.isPrimitive();
1379 result &= (retValIsPrimitive == tRet.isPrimitive()) &&
1380 (retValIsPrimitive != sRet.isPrimitive());
1381 }
1382 } else {
1383 result &= compatibleBySubtyping(tRet, sRet);
1384 }
1385 }
1386 }
1387 //where
1388
1389 private List<JCExpression> lambdaResults(JCLambda lambda) {
1390 if (lambda.getBodyKind() == JCTree.JCLambda.BodyKind.EXPRESSION) {
1391 return List.of(asExpr((JCExpression) lambda.body));
1392 } else {
1393 final ListBuffer<JCExpression> buffer = new ListBuffer<>();
1394 DeferredAttr.LambdaReturnScanner lambdaScanner =
1395 new DeferredAttr.LambdaReturnScanner() {
1396 @Override
1397 public void visitReturn(JCReturn tree) {
1398 if (tree.expr != null) {
1399 buffer.append(asExpr(tree.expr));
1400 }
1401 }
1402 };
1403 lambdaScanner.scan(lambda.body);
1404 return buffer.toList();
1405 }
1406 }
1407
1408 private JCExpression asExpr(JCExpression expr) {
1409 if (expr.type.hasTag(DEFERRED)) {
1410 JCTree speculativeTree = ((DeferredType)expr.type).speculativeTree(deferredAttrContext);
1411 if (speculativeTree != deferredAttr.stuckTree) {
1412 expr = (JCExpression)speculativeTree;
1413 }
1414 }
1415 return expr;
1416 }
1417 }
1418
1419 }
1420
1421 public MethodCheck mostSpecificCheck(List<Type> actuals) {
1422 Assert.error("Cannot get here!");
1423 return null;
1424 }
1425 }
1426
1427 public static class InapplicableMethodException extends CompilerInternalException {
1428 private static final long serialVersionUID = 0;
1429
1430 transient JCDiagnostic diagnostic;
1431
1432 InapplicableMethodException(JCDiagnostic diag, boolean dumpStackTraceOnError) {
1433 super(dumpStackTraceOnError);
1434 this.diagnostic = diag;
1435 }
1436
1437 public JCDiagnostic getDiagnostic() {
1438 return diagnostic;
1439 }
1440 }
1441
1442 /* ***************************************************************************
1443 * Symbol lookup
1444 * the following naming conventions for arguments are used
1445 *
1446 * env is the environment where the symbol was mentioned
1447 * site is the type of which the symbol is a member
1448 * name is the symbol's name
1449 * if no arguments are given
1450 * argtypes are the value arguments, if we search for a method
1451 *
1452 * If no symbol was found, a ResolveError detailing the problem is returned.
1453 ****************************************************************************/
1454
1455 /** Find field. Synthetic fields are always skipped.
1456 * @param env The current environment.
1457 * @param site The original type from where the selection takes place.
1458 * @param name The name of the field.
1459 * @param c The class to search for the field. This is always
1460 * a superclass or implemented interface of site's class.
1461 */
1462 Symbol findField(Env<AttrContext> env,
1463 Type site,
1464 Name name,
1465 TypeSymbol c) {
1466 while (c.type.hasTag(TYPEVAR))
1467 c = c.type.getUpperBound().tsym;
1468 Symbol bestSoFar = varNotFound;
1469 Symbol sym;
1470 for (Symbol s : c.members().getSymbolsByName(name)) {
1471 if (s.kind == VAR && (s.flags_field & SYNTHETIC) == 0) {
1472 return isAccessible(env, site, s)
1473 ? s : new AccessError(env, site, s);
1474 }
1475 }
1476 Type st = types.supertype(c.type);
1477 if (st != null && (st.hasTag(CLASS) || st.hasTag(TYPEVAR))) {
1478 sym = findField(env, site, name, st.tsym);
1479 bestSoFar = bestOf(bestSoFar, sym);
1480 }
1481 for (List<Type> l = types.interfaces(c.type);
1482 bestSoFar.kind != AMBIGUOUS && l.nonEmpty();
1483 l = l.tail) {
1484 sym = findField(env, site, name, l.head.tsym);
1485 if (bestSoFar.exists() && sym.exists() &&
1486 sym.owner != bestSoFar.owner)
1487 bestSoFar = new AmbiguityError(bestSoFar, sym);
1488 else
1489 bestSoFar = bestOf(bestSoFar, sym);
1490 }
1491 return bestSoFar;
1492 }
1493
1494 /** Resolve a field identifier, throw a fatal error if not found.
1495 * @param pos The position to use for error reporting.
1496 * @param env The environment current at the method invocation.
1497 * @param site The type of the qualifying expression, in which
1498 * identifier is searched.
1499 * @param name The identifier's name.
1500 */
1501 public VarSymbol resolveInternalField(DiagnosticPosition pos, Env<AttrContext> env,
1502 Type site, Name name) {
1503 Symbol sym = findField(env, site, name, site.tsym);
1504 if (sym.kind == VAR) return (VarSymbol)sym;
1505 else throw new FatalError(
1506 diags.fragment(Fragments.FatalErrCantLocateField(name)));
1507 }
1508
1509 /** Find unqualified variable or field with given name.
1510 * Synthetic fields always skipped.
1511 * @param pos The position to use for error reporting.
1512 * @param env The current environment.
1513 * @param name The name of the variable or field.
1514 */
1515 Symbol findVar(DiagnosticPosition pos, Env<AttrContext> env, Name name) {
1516 Symbol bestSoFar = varNotFound;
1517 Env<AttrContext> env1 = env;
1518 boolean staticOnly = false;
1519 while (env1.outer != null) {
1520 Symbol sym = null;
1521 for (Symbol s : env1.info.scope.getSymbolsByName(name)) {
1522 if (s.kind == VAR && (s.flags_field & SYNTHETIC) == 0) {
1523 sym = s;
1524 if (staticOnly) {
1525 return new StaticError(sym);
1526 }
1527 break;
1528 }
1529 }
1530 if (isStatic(env1)) staticOnly = true;
1531 if (sym == null) {
1532 sym = findField(env1, env1.enclClass.sym.type, name, env1.enclClass.sym);
1533 }
1534 if (sym.exists()) {
1535 if (sym.kind == VAR &&
1536 sym.owner.kind == TYP &&
1537 (sym.flags() & STATIC) == 0) {
1538 if (staticOnly)
1539 return new StaticError(sym);
1540 if (env1.info.ctorPrologue && !isAllowedEarlyReference(pos, env1, (VarSymbol)sym)) {
1541 if (!env.tree.hasTag(ASSIGN) || !TreeInfo.isIdentOrThisDotIdent(((JCAssign)env.tree).lhs)) {
1542 if (!sym.isStrictInstance()) {
1543 return new RefBeforeCtorCalledError(sym);
1544 } else {
1545 localProxyVarsGen.addStrictFieldReadInPrologue(env.enclMethod, sym);
1546 return sym;
1547 }
1548 }
1549 }
1550 }
1551 return sym;
1552 } else {
1553 bestSoFar = bestOf(bestSoFar, sym);
1554 }
1555
1556 if ((env1.enclClass.sym.flags() & STATIC) != 0) staticOnly = true;
1557 env1 = env1.outer;
1558 }
1559
1560 Symbol sym = findField(env, syms.predefClass.type, name, syms.predefClass);
1561 if (sym.exists())
1562 return sym;
1563 if (bestSoFar.exists())
1564 return bestSoFar;
1565
1566 Symbol origin = null;
1567 for (Scope sc : new Scope[] { env.toplevel.namedImportScope, env.toplevel.starImportScope }) {
1568 for (Symbol currentSymbol : sc.getSymbolsByName(name)) {
1569 if (currentSymbol.kind != VAR)
1570 continue;
1571 // invariant: sym.kind == Symbol.Kind.VAR
1572 if (!bestSoFar.kind.isResolutionError() &&
1573 currentSymbol.owner != bestSoFar.owner)
1574 return new AmbiguityError(bestSoFar, currentSymbol);
1575 else if (!bestSoFar.kind.betterThan(VAR)) {
1576 origin = sc.getOrigin(currentSymbol).owner;
1577 bestSoFar = isAccessible(env, origin.type, currentSymbol)
1578 ? currentSymbol : new AccessError(env, origin.type, currentSymbol);
1579 }
1580 }
1581 if (bestSoFar.exists()) break;
1582 }
1583 if (bestSoFar.kind == VAR && bestSoFar.owner.type != origin.type)
1584 return bestSoFar.clone(origin);
1585 else
1586 return bestSoFar;
1587 }
1588
1589 Warner noteWarner = new Warner();
1590
1591 /** Select the best method for a call site among two choices.
1592 * @param env The current environment.
1593 * @param site The original type from where the
1594 * selection takes place.
1595 * @param argtypes The invocation's value arguments,
1596 * @param typeargtypes The invocation's type arguments,
1597 * @param sym Proposed new best match.
1598 * @param bestSoFar Previously found best match.
1599 * @param allowBoxing Allow boxing conversions of arguments.
1600 * @param useVarargs Box trailing arguments into an array for varargs.
1601 */
1602 @SuppressWarnings("fallthrough")
1603 Symbol selectBest(Env<AttrContext> env,
1604 Type site,
1605 List<Type> argtypes,
1606 List<Type> typeargtypes,
1607 Symbol sym,
1608 Symbol bestSoFar,
1609 boolean allowBoxing,
1610 boolean useVarargs) {
1611 if (sym.kind == ERR ||
1612 (site.tsym != sym.owner && !sym.isInheritedIn(site.tsym, types)) ||
1613 !notOverriddenIn(site, sym)) {
1614 return bestSoFar;
1615 } else if (useVarargs && (sym.flags() & VARARGS) == 0) {
1616 return bestSoFar.kind.isResolutionError() ?
1617 new BadVarargsMethod((ResolveError)bestSoFar.baseSymbol()) :
1618 bestSoFar;
1619 }
1620 Assert.check(!sym.kind.isResolutionError());
1621 try {
1622 types.noWarnings.clear();
1623 Type mt = rawInstantiate(env, site, sym, null, argtypes, typeargtypes,
1624 allowBoxing, useVarargs, types.noWarnings);
1625 currentResolutionContext.addApplicableCandidate(sym, mt);
1626 } catch (InapplicableMethodException ex) {
1627 currentResolutionContext.addInapplicableCandidate(sym, ex.getDiagnostic());
1628 // Currently, an InapplicableMethodException occurs.
1629 // If bestSoFar.kind was ABSENT_MTH, return an InapplicableSymbolError(kind is WRONG_MTH).
1630 // If bestSoFar.kind was HIDDEN(AccessError)/WRONG_MTH/WRONG_MTHS, return an InapplicableSymbolsError(kind is WRONG_MTHS).
1631 // See JDK-8255968 for more information.
1632 switch (bestSoFar.kind) {
1633 case ABSENT_MTH:
1634 return new InapplicableSymbolError(currentResolutionContext);
1635 case HIDDEN:
1636 if (bestSoFar instanceof AccessError accessError) {
1637 // Add the JCDiagnostic of previous AccessError to the currentResolutionContext
1638 // and construct InapplicableSymbolsError.
1639 // Intentionally fallthrough.
1640 currentResolutionContext.addInapplicableCandidate(accessError.sym,
1641 accessError.getDiagnostic(JCDiagnostic.DiagnosticType.FRAGMENT, null, null, site, null, argtypes, typeargtypes));
1642 } else {
1643 return bestSoFar;
1644 }
1645 case WRONG_MTH:
1646 bestSoFar = new InapplicableSymbolsError(currentResolutionContext);
1647 default:
1648 return bestSoFar;
1649 }
1650 }
1651 if (!isAccessible(env, site, sym)) {
1652 AccessError curAccessError = new AccessError(env, site, sym);
1653 JCDiagnostic curDiagnostic = curAccessError.getDiagnostic(JCDiagnostic.DiagnosticType.FRAGMENT, null, null, site, null, argtypes, typeargtypes);
1654 // Currently, an AccessError occurs.
1655 // If bestSoFar.kind was ABSENT_MTH, return an AccessError(kind is HIDDEN).
1656 // If bestSoFar.kind was HIDDEN(AccessError), WRONG_MTH, WRONG_MTHS, return an InapplicableSymbolsError(kind is WRONG_MTHS).
1657 // See JDK-8255968 for more information.
1658 if (bestSoFar.kind == ABSENT_MTH) {
1659 bestSoFar = curAccessError;
1660 } else if (bestSoFar.kind == WRONG_MTH) {
1661 // Add the JCDiagnostic of current AccessError to the currentResolutionContext
1662 // and construct InapplicableSymbolsError.
1663 currentResolutionContext.addInapplicableCandidate(sym, curDiagnostic);
1664 bestSoFar = new InapplicableSymbolsError(currentResolutionContext);
1665 } else if (bestSoFar.kind == WRONG_MTHS) {
1666 // Add the JCDiagnostic of current AccessError to the currentResolutionContext
1667 currentResolutionContext.addInapplicableCandidate(sym, curDiagnostic);
1668 } else if (bestSoFar.kind == HIDDEN && bestSoFar instanceof AccessError accessError) {
1669 // Add the JCDiagnostics of previous and current AccessError to the currentResolutionContext
1670 // and construct InapplicableSymbolsError.
1671 currentResolutionContext.addInapplicableCandidate(accessError.sym,
1672 accessError.getDiagnostic(JCDiagnostic.DiagnosticType.FRAGMENT, null, null, site, null, argtypes, typeargtypes));
1673 currentResolutionContext.addInapplicableCandidate(sym, curDiagnostic);
1674 bestSoFar = new InapplicableSymbolsError(currentResolutionContext);
1675 }
1676 return bestSoFar;
1677 }
1678 return (bestSoFar.kind.isResolutionError() && bestSoFar.kind != AMBIGUOUS)
1679 ? sym
1680 : mostSpecific(argtypes, sym, bestSoFar, env, site, useVarargs);
1681 }
1682
1683 /* Return the most specific of the two methods for a call,
1684 * given that both are accessible and applicable.
1685 * @param m1 A new candidate for most specific.
1686 * @param m2 The previous most specific candidate.
1687 * @param env The current environment.
1688 * @param site The original type from where the selection
1689 * takes place.
1690 * @param allowBoxing Allow boxing conversions of arguments.
1691 * @param useVarargs Box trailing arguments into an array for varargs.
1692 */
1693 Symbol mostSpecific(List<Type> argtypes, Symbol m1,
1694 Symbol m2,
1695 Env<AttrContext> env,
1696 final Type site,
1697 boolean useVarargs) {
1698 switch (m2.kind) {
1699 case MTH:
1700 if (m1 == m2) return m1;
1701 boolean m1SignatureMoreSpecific =
1702 signatureMoreSpecific(argtypes, env, site, m1, m2, useVarargs);
1703 boolean m2SignatureMoreSpecific =
1704 signatureMoreSpecific(argtypes, env, site, m2, m1, useVarargs);
1705 if (m1SignatureMoreSpecific && m2SignatureMoreSpecific) {
1706 Type mt1 = types.memberType(site, m1);
1707 Type mt2 = types.memberType(site, m2);
1708 if (!types.overrideEquivalent(mt1, mt2))
1709 return ambiguityError(m1, m2);
1710
1711 // same signature; select (a) the non-bridge method, or
1712 // (b) the one that overrides the other, or (c) the concrete
1713 // one, or (d) merge both abstract signatures
1714 if ((m1.flags() & BRIDGE) != (m2.flags() & BRIDGE))
1715 return ((m1.flags() & BRIDGE) != 0) ? m2 : m1;
1716
1717 if (m1.baseSymbol() == m2.baseSymbol()) {
1718 // this is the same imported symbol which has been cloned twice.
1719 // Return the first one (either will do).
1720 return m1;
1721 }
1722
1723 // if one overrides or hides the other, use it
1724 TypeSymbol m1Owner = (TypeSymbol)m1.owner;
1725 TypeSymbol m2Owner = (TypeSymbol)m2.owner;
1726 // the two owners can never be the same if the target methods are compiled from source,
1727 // but we need to protect against cases where the methods are defined in some classfile
1728 // and make sure we issue an ambiguity error accordingly (by skipping the logic below).
1729 if (m1Owner != m2Owner) {
1730 if (types.asSuper(m1Owner.type, m2Owner) != null &&
1731 ((m1.owner.flags_field & INTERFACE) == 0 ||
1732 (m2.owner.flags_field & INTERFACE) != 0) &&
1733 m1.overrides(m2, m1Owner, types, false))
1734 return m1;
1735 if (types.asSuper(m2Owner.type, m1Owner) != null &&
1736 ((m2.owner.flags_field & INTERFACE) == 0 ||
1737 (m1.owner.flags_field & INTERFACE) != 0) &&
1738 m2.overrides(m1, m2Owner, types, false))
1739 return m2;
1740 }
1741 boolean m1Abstract = (m1.flags() & ABSTRACT) != 0;
1742 boolean m2Abstract = (m2.flags() & ABSTRACT) != 0;
1743 if (m1Abstract && !m2Abstract) return m2;
1744 if (m2Abstract && !m1Abstract) return m1;
1745 // both abstract or both concrete
1746 return ambiguityError(m1, m2);
1747 }
1748 if (m1SignatureMoreSpecific) return m1;
1749 if (m2SignatureMoreSpecific) return m2;
1750 return ambiguityError(m1, m2);
1751 case AMBIGUOUS:
1752 //compare m1 to ambiguous methods in m2
1753 AmbiguityError e = (AmbiguityError)m2.baseSymbol();
1754 boolean m1MoreSpecificThanAnyAmbiguous = true;
1755 boolean allAmbiguousMoreSpecificThanM1 = true;
1756 for (Symbol s : e.ambiguousSyms) {
1757 Symbol moreSpecific = mostSpecific(argtypes, m1, s, env, site, useVarargs);
1758 m1MoreSpecificThanAnyAmbiguous &= moreSpecific == m1;
1759 allAmbiguousMoreSpecificThanM1 &= moreSpecific == s;
1760 }
1761 if (m1MoreSpecificThanAnyAmbiguous)
1762 return m1;
1763 //if m1 is more specific than some ambiguous methods, but other ambiguous methods are
1764 //more specific than m1, add it as a new ambiguous method:
1765 if (!allAmbiguousMoreSpecificThanM1)
1766 e.addAmbiguousSymbol(m1);
1767 return e;
1768 default:
1769 throw new AssertionError();
1770 }
1771 }
1772 //where
1773 private boolean signatureMoreSpecific(List<Type> actuals, Env<AttrContext> env, Type site, Symbol m1, Symbol m2, boolean useVarargs) {
1774 noteWarner.clear();
1775 int maxLength = Math.max(
1776 Math.max(m1.type.getParameterTypes().length(), actuals.length()),
1777 m2.type.getParameterTypes().length());
1778 MethodResolutionContext prevResolutionContext = currentResolutionContext;
1779 try {
1780 currentResolutionContext = new MethodResolutionContext();
1781 currentResolutionContext.step = prevResolutionContext.step;
1782 currentResolutionContext.methodCheck =
1783 prevResolutionContext.methodCheck.mostSpecificCheck(actuals);
1784 Type mst = instantiate(env, site, m2, null,
1785 adjustArgs(types.cvarLowerBounds(types.memberType(site, m1).getParameterTypes()), m1, maxLength, useVarargs), null,
1786 false, useVarargs, noteWarner);
1787 return mst != null &&
1788 !noteWarner.hasLint(Lint.LintCategory.UNCHECKED);
1789 } finally {
1790 currentResolutionContext = prevResolutionContext;
1791 }
1792 }
1793
1794 List<Type> adjustArgs(List<Type> args, Symbol msym, int length, boolean allowVarargs) {
1795 if ((msym.flags() & VARARGS) != 0 && allowVarargs) {
1796 Type varargsElem = types.elemtype(args.last());
1797 if (varargsElem == null) {
1798 Assert.error("Bad varargs = " + args.last() + " " + msym);
1799 }
1800 List<Type> newArgs = args.reverse().tail.prepend(varargsElem).reverse();
1801 while (newArgs.length() < length) {
1802 newArgs = newArgs.append(newArgs.last());
1803 }
1804 return newArgs;
1805 } else {
1806 return args;
1807 }
1808 }
1809 //where
1810 Symbol ambiguityError(Symbol m1, Symbol m2) {
1811 if (((m1.flags() | m2.flags()) & CLASH) != 0) {
1812 return (m1.flags() & CLASH) == 0 ? m1 : m2;
1813 } else {
1814 return new AmbiguityError(m1, m2);
1815 }
1816 }
1817
1818 Symbol findMethodInScope(Env<AttrContext> env,
1819 Type site,
1820 Name name,
1821 List<Type> argtypes,
1822 List<Type> typeargtypes,
1823 Scope sc,
1824 Symbol bestSoFar,
1825 boolean allowBoxing,
1826 boolean useVarargs,
1827 boolean abstractok) {
1828 for (Symbol s : sc.getSymbolsByName(name, new LookupFilter(abstractok))) {
1829 bestSoFar = selectBest(env, site, argtypes, typeargtypes, s,
1830 bestSoFar, allowBoxing, useVarargs);
1831 }
1832 return bestSoFar;
1833 }
1834 //where
1835 class LookupFilter implements Predicate<Symbol> {
1836
1837 boolean abstractOk;
1838
1839 LookupFilter(boolean abstractOk) {
1840 this.abstractOk = abstractOk;
1841 }
1842
1843 @Override
1844 public boolean test(Symbol s) {
1845 long flags = s.flags();
1846 return s.kind == MTH &&
1847 (flags & SYNTHETIC) == 0 &&
1848 (abstractOk ||
1849 (flags & DEFAULT) != 0 ||
1850 (flags & ABSTRACT) == 0);
1851 }
1852 }
1853
1854 /** Find best qualified method matching given name, type and value
1855 * arguments.
1856 * @param env The current environment.
1857 * @param site The original type from where the selection
1858 * takes place.
1859 * @param name The method's name.
1860 * @param argtypes The method's value arguments.
1861 * @param typeargtypes The method's type arguments
1862 * @param allowBoxing Allow boxing conversions of arguments.
1863 * @param useVarargs Box trailing arguments into an array for varargs.
1864 */
1865 Symbol findMethod(Env<AttrContext> env,
1866 Type site,
1867 Name name,
1868 List<Type> argtypes,
1869 List<Type> typeargtypes,
1870 boolean allowBoxing,
1871 boolean useVarargs) {
1872 Symbol bestSoFar = methodNotFound;
1873 bestSoFar = findMethod(env,
1874 site,
1875 name,
1876 argtypes,
1877 typeargtypes,
1878 site.tsym.type,
1879 bestSoFar,
1880 allowBoxing,
1881 useVarargs);
1882 if (bestSoFar.kind == AMBIGUOUS) {
1883 AmbiguityError a_err = (AmbiguityError)bestSoFar.baseSymbol();
1884 bestSoFar = a_err.mergeAbstracts(site);
1885 }
1886 return bestSoFar;
1887 }
1888 // where
1889 private Symbol findMethod(Env<AttrContext> env,
1890 Type site,
1891 Name name,
1892 List<Type> argtypes,
1893 List<Type> typeargtypes,
1894 Type intype,
1895 Symbol bestSoFar,
1896 boolean allowBoxing,
1897 boolean useVarargs) {
1898 @SuppressWarnings({"unchecked","rawtypes"})
1899 List<Type>[] itypes = (List<Type>[])new List[] { List.<Type>nil(), List.<Type>nil() };
1900
1901 InterfaceLookupPhase iphase = InterfaceLookupPhase.ABSTRACT_OK;
1902 boolean isInterface = site.tsym.isInterface();
1903 for (TypeSymbol s : isInterface ? List.of(intype.tsym) : superclasses(intype)) {
1904 bestSoFar = findMethodInScope(env, site, name, argtypes, typeargtypes,
1905 s.members(), bestSoFar, allowBoxing, useVarargs, true);
1906 if (name == names.init) return bestSoFar;
1907 iphase = (iphase == null) ? null : iphase.update(s, this);
1908 if (iphase != null) {
1909 for (Type itype : types.interfaces(s.type)) {
1910 itypes[iphase.ordinal()] = types.union(types.closure(itype), itypes[iphase.ordinal()]);
1911 }
1912 }
1913 }
1914
1915 Symbol concrete = bestSoFar.kind.isValid() &&
1916 (bestSoFar.flags() & ABSTRACT) == 0 ?
1917 bestSoFar : methodNotFound;
1918
1919 for (InterfaceLookupPhase iphase2 : InterfaceLookupPhase.values()) {
1920 //keep searching for abstract methods
1921 for (Type itype : itypes[iphase2.ordinal()]) {
1922 if (!itype.isInterface()) continue; //skip j.l.Object (included by Types.closure())
1923 if (iphase2 == InterfaceLookupPhase.DEFAULT_OK &&
1924 (itype.tsym.flags() & DEFAULT) == 0) continue;
1925 bestSoFar = findMethodInScope(env, site, name, argtypes, typeargtypes,
1926 itype.tsym.members(), bestSoFar, allowBoxing, useVarargs, true);
1927 if (concrete != bestSoFar &&
1928 concrete.kind.isValid() &&
1929 bestSoFar.kind.isValid() &&
1930 types.isSubSignature(concrete.type, bestSoFar.type)) {
1931 //this is an hack - as javac does not do full membership checks
1932 //most specific ends up comparing abstract methods that might have
1933 //been implemented by some concrete method in a subclass and,
1934 //because of raw override, it is possible for an abstract method
1935 //to be more specific than the concrete method - so we need
1936 //to explicitly call that out (see CR 6178365)
1937 bestSoFar = concrete;
1938 }
1939 }
1940 }
1941 if (isInterface && bestSoFar.kind.isResolutionError()) {
1942 bestSoFar = findMethodInScope(env, site, name, argtypes, typeargtypes,
1943 syms.objectType.tsym.members(), bestSoFar, allowBoxing, useVarargs, true);
1944 if (bestSoFar.kind.isValid()) {
1945 Symbol baseSymbol = bestSoFar;
1946 bestSoFar = new MethodSymbol(bestSoFar.flags_field, bestSoFar.name, bestSoFar.type, intype.tsym) {
1947 @Override
1948 public Symbol baseSymbol() {
1949 return baseSymbol;
1950 }
1951 };
1952 }
1953 }
1954 return bestSoFar;
1955 }
1956
1957 enum InterfaceLookupPhase {
1958 ABSTRACT_OK() {
1959 @Override
1960 InterfaceLookupPhase update(Symbol s, Resolve rs) {
1961 //We should not look for abstract methods if receiver is a concrete class
1962 //(as concrete classes are expected to implement all abstracts coming
1963 //from superinterfaces)
1964 if ((s.flags() & (ABSTRACT | INTERFACE | ENUM)) != 0) {
1965 return this;
1966 } else {
1967 return DEFAULT_OK;
1968 }
1969 }
1970 },
1971 DEFAULT_OK() {
1972 @Override
1973 InterfaceLookupPhase update(Symbol s, Resolve rs) {
1974 return this;
1975 }
1976 };
1977
1978 abstract InterfaceLookupPhase update(Symbol s, Resolve rs);
1979 }
1980
1981 /**
1982 * Return an Iterable object to scan the superclasses of a given type.
1983 * It's crucial that the scan is done lazily, as we don't want to accidentally
1984 * access more supertypes than strictly needed (as this could trigger completion
1985 * errors if some of the not-needed supertypes are missing/ill-formed).
1986 */
1987 Iterable<TypeSymbol> superclasses(final Type intype) {
1988 return () -> new Iterator<TypeSymbol>() {
1989
1990 List<TypeSymbol> seen = List.nil();
1991 TypeSymbol currentSym = symbolFor(intype);
1992 TypeSymbol prevSym = null;
1993
1994 public boolean hasNext() {
1995 if (currentSym == syms.noSymbol) {
1996 currentSym = symbolFor(types.supertype(prevSym.type));
1997 }
1998 return currentSym != null;
1999 }
2000
2001 public TypeSymbol next() {
2002 prevSym = currentSym;
2003 currentSym = syms.noSymbol;
2004 Assert.check(prevSym != null || prevSym != syms.noSymbol);
2005 return prevSym;
2006 }
2007
2008 public void remove() {
2009 throw new UnsupportedOperationException();
2010 }
2011
2012 TypeSymbol symbolFor(Type t) {
2013 if (!t.hasTag(CLASS) &&
2014 !t.hasTag(TYPEVAR)) {
2015 return null;
2016 }
2017 t = types.skipTypeVars(t, false);
2018 if (seen.contains(t.tsym)) {
2019 //degenerate case in which we have a circular
2020 //class hierarchy - because of ill-formed classfiles
2021 return null;
2022 }
2023 seen = seen.prepend(t.tsym);
2024 return t.tsym;
2025 }
2026 };
2027 }
2028
2029 /** Find unqualified method matching given name, type and value arguments.
2030 * @param env The current environment.
2031 * @param name The method's name.
2032 * @param argtypes The method's value arguments.
2033 * @param typeargtypes The method's type arguments.
2034 * @param allowBoxing Allow boxing conversions of arguments.
2035 * @param useVarargs Box trailing arguments into an array for varargs.
2036 */
2037 Symbol findFun(Env<AttrContext> env, Name name,
2038 List<Type> argtypes, List<Type> typeargtypes,
2039 boolean allowBoxing, boolean useVarargs) {
2040 Symbol bestSoFar = methodNotFound;
2041 Env<AttrContext> env1 = env;
2042 boolean staticOnly = false;
2043 while (env1.outer != null) {
2044 if (isStatic(env1)) staticOnly = true;
2045 Assert.check(env1.info.preferredTreeForDiagnostics == null);
2046 env1.info.preferredTreeForDiagnostics = env.tree;
2047 try {
2048 Symbol sym = findMethod(
2049 env1, env1.enclClass.sym.type, name, argtypes, typeargtypes,
2050 allowBoxing, useVarargs);
2051 if (sym.exists()) {
2052 if (sym.kind == MTH &&
2053 sym.owner.kind == TYP &&
2054 (sym.flags() & STATIC) == 0) {
2055 if (staticOnly)
2056 return new StaticError(sym);
2057 if (env1.info.ctorPrologue && env1 == env)
2058 return new RefBeforeCtorCalledError(sym);
2059 }
2060 return sym;
2061 } else {
2062 bestSoFar = bestOf(bestSoFar, sym);
2063 }
2064 } finally {
2065 env1.info.preferredTreeForDiagnostics = null;
2066 }
2067 if ((env1.enclClass.sym.flags() & STATIC) != 0) staticOnly = true;
2068 env1 = env1.outer;
2069 }
2070
2071 Symbol sym = findMethod(env, syms.predefClass.type, name, argtypes,
2072 typeargtypes, allowBoxing, useVarargs);
2073 if (sym.exists())
2074 return sym;
2075
2076 for (Symbol currentSym : env.toplevel.namedImportScope.getSymbolsByName(name)) {
2077 Symbol origin = env.toplevel.namedImportScope.getOrigin(currentSym).owner;
2078 if (currentSym.kind == MTH) {
2079 if (currentSym.owner.type != origin.type)
2080 currentSym = currentSym.clone(origin);
2081 if (!isAccessible(env, origin.type, currentSym))
2082 currentSym = new AccessError(env, origin.type, currentSym);
2083 bestSoFar = selectBest(env, origin.type,
2084 argtypes, typeargtypes,
2085 currentSym, bestSoFar,
2086 allowBoxing, useVarargs);
2087 }
2088 }
2089 if (bestSoFar.exists())
2090 return bestSoFar;
2091
2092 for (Symbol currentSym : env.toplevel.starImportScope.getSymbolsByName(name)) {
2093 Symbol origin = env.toplevel.starImportScope.getOrigin(currentSym).owner;
2094 if (currentSym.kind == MTH) {
2095 if (currentSym.owner.type != origin.type)
2096 currentSym = currentSym.clone(origin);
2097 if (!isAccessible(env, origin.type, currentSym))
2098 currentSym = new AccessError(env, origin.type, currentSym);
2099 bestSoFar = selectBest(env, origin.type,
2100 argtypes, typeargtypes,
2101 currentSym, bestSoFar,
2102 allowBoxing, useVarargs);
2103 }
2104 }
2105 return bestSoFar;
2106 }
2107
2108 /** Load toplevel or member class with given fully qualified name and
2109 * verify that it is accessible.
2110 * @param env The current environment.
2111 * @param name The fully qualified name of the class to be loaded.
2112 */
2113 Symbol loadClass(Env<AttrContext> env, Name name, RecoveryLoadClass recoveryLoadClass) {
2114 try {
2115 ClassSymbol c = finder.loadClass(env.toplevel.modle, name);
2116 return isAccessible(env, c) ? c : new AccessError(env, null, c);
2117 } catch (ClassFinder.BadClassFile err) {
2118 return new BadClassFileError(err);
2119 } catch (CompletionFailure ex) {
2120 Symbol candidate = recoveryLoadClass.loadClass(env, name);
2121
2122 if (candidate != null) {
2123 return candidate;
2124 }
2125
2126 return typeNotFound;
2127 }
2128 }
2129
2130 public interface RecoveryLoadClass {
2131 Symbol loadClass(Env<AttrContext> env, Name name);
2132 }
2133
2134 private final RecoveryLoadClass noRecovery = (env, name) -> null;
2135
2136 private final RecoveryLoadClass doRecoveryLoadClass = new RecoveryLoadClass() {
2137 @Override public Symbol loadClass(Env<AttrContext> env, Name name) {
2138 List<Name> candidates = Convert.classCandidates(name);
2139 return lookupInvisibleSymbol(env, name,
2140 n -> () -> createCompoundIterator(candidates,
2141 c -> syms.getClassesForName(c)
2142 .iterator()),
2143 (ms, n) -> {
2144 for (Name candidate : candidates) {
2145 try {
2146 return finder.loadClass(ms, candidate);
2147 } catch (CompletionFailure cf) {
2148 //ignore
2149 }
2150 }
2151 return null;
2152 }, sym -> sym.kind == Kind.TYP, typeNotFound);
2153 }
2154 };
2155
2156 private final RecoveryLoadClass namedImportScopeRecovery = (env, name) -> {
2157 Scope importScope = env.toplevel.namedImportScope;
2158 Symbol existing = importScope.findFirst(Convert.shortName(name),
2159 sym -> sym.kind == TYP && sym.flatName() == name);
2160
2161 if (existing != null) {
2162 return new InvisibleSymbolError(env, true, existing);
2163 }
2164 return null;
2165 };
2166
2167 private final RecoveryLoadClass starImportScopeRecovery =
2168 onDemandImportScopeRecovery(false);
2169
2170 private final RecoveryLoadClass moduleImportScopeRecovery =
2171 onDemandImportScopeRecovery(true);
2172
2173 private RecoveryLoadClass onDemandImportScopeRecovery(boolean moduleImportScope) {
2174 return (env, name) -> {
2175 Scope importScope = moduleImportScope ? env.toplevel.moduleImportScope
2176 : env.toplevel.starImportScope;
2177 Symbol existing = importScope.findFirst(Convert.shortName(name),
2178 sym -> sym.kind == TYP && sym.flatName() == name);
2179
2180 if (existing != null) {
2181 try {
2182 existing = finder.loadClass(existing.packge().modle, name);
2183
2184 return new InvisibleSymbolError(env, true, existing);
2185 } catch (CompletionFailure cf) {
2186 //ignore
2187 }
2188 }
2189
2190 return null;
2191 };
2192 }
2193
2194 Symbol lookupPackage(Env<AttrContext> env, Name name) {
2195 PackageSymbol pack = syms.lookupPackage(env.toplevel.modle, name);
2196
2197 if (allowModules && isImportOnDemand(env, name)) {
2198 if (pack.members().isEmpty()) {
2199 return lookupInvisibleSymbol(env, name, syms::getPackagesForName, syms::enterPackage, sym -> {
2200 sym.complete();
2201 return !sym.members().isEmpty();
2202 }, pack);
2203 }
2204 }
2205
2206 return pack;
2207 }
2208
2209 private boolean isImportOnDemand(Env<AttrContext> env, Name name) {
2210 if (!env.tree.hasTag(IMPORT))
2211 return false;
2212
2213 JCTree qualid = ((JCImport) env.tree).qualid;
2214
2215 if (!qualid.hasTag(SELECT))
2216 return false;
2217
2218 if (TreeInfo.name(qualid) != names.asterisk)
2219 return false;
2220
2221 return TreeInfo.fullName(((JCFieldAccess) qualid).selected) == name;
2222 }
2223
2224 private <S extends Symbol> Symbol lookupInvisibleSymbol(Env<AttrContext> env,
2225 Name name,
2226 Function<Name, Iterable<S>> get,
2227 BiFunction<ModuleSymbol, Name, S> load,
2228 Predicate<S> validate,
2229 Symbol defaultResult) {
2230 //even if a class/package cannot be found in the current module and among packages in modules
2231 //it depends on that are exported for any or this module, the class/package may exist internally
2232 //in some of these modules, or may exist in a module on which this module does not depend.
2233 //Provide better diagnostic in such cases by looking for the class in any module:
2234 Iterable<? extends S> candidates = get.apply(name);
2235
2236 for (S sym : candidates) {
2237 if (validate.test(sym))
2238 return createInvisibleSymbolError(env, sym);
2239 }
2240
2241 Set<ModuleSymbol> recoverableModules = new HashSet<>(syms.getAllModules());
2242
2243 recoverableModules.add(syms.unnamedModule);
2244 recoverableModules.remove(env.toplevel.modle);
2245
2246 for (ModuleSymbol ms : recoverableModules) {
2247 //avoid overly eager completing classes from source-based modules, as those
2248 //may not be completable with the current compiler settings:
2249 if (ms.sourceLocation == null) {
2250 if (ms.classLocation == null) {
2251 ms = moduleFinder.findModule(ms);
2252 }
2253
2254 if (ms.kind != ERR) {
2255 S sym = load.apply(ms, name);
2256
2257 if (sym != null && validate.test(sym)) {
2258 return createInvisibleSymbolError(env, sym);
2259 }
2260 }
2261 }
2262 }
2263
2264 return defaultResult;
2265 }
2266
2267 private Symbol createInvisibleSymbolError(Env<AttrContext> env, Symbol sym) {
2268 if (symbolPackageVisible(env, sym)) {
2269 return new AccessError(env, null, sym);
2270 } else {
2271 return new InvisibleSymbolError(env, false, sym);
2272 }
2273 }
2274
2275 private boolean symbolPackageVisible(Env<AttrContext> env, Symbol sym) {
2276 ModuleSymbol envMod = env.toplevel.modle;
2277 PackageSymbol symPack = sym.packge();
2278 return envMod == symPack.modle ||
2279 envMod.visiblePackages.containsKey(symPack.fullname);
2280 }
2281
2282 /**
2283 * Find a type declared in a scope (not inherited). Return null
2284 * if none is found.
2285 * @param env The current environment.
2286 * @param site The original type from where the selection takes
2287 * place.
2288 * @param name The type's name.
2289 * @param c The class to search for the member type. This is
2290 * always a superclass or implemented interface of
2291 * site's class.
2292 */
2293 Symbol findImmediateMemberType(Env<AttrContext> env,
2294 Type site,
2295 Name name,
2296 TypeSymbol c) {
2297 for (Symbol sym : c.members().getSymbolsByName(name)) {
2298 if (sym.kind == TYP) {
2299 return isAccessible(env, site, sym)
2300 ? sym
2301 : new AccessError(env, site, sym);
2302 }
2303 }
2304 return typeNotFound;
2305 }
2306
2307 /** Find a member type inherited from a superclass or interface.
2308 * @param env The current environment.
2309 * @param site The original type from where the selection takes
2310 * place.
2311 * @param name The type's name.
2312 * @param c The class to search for the member type. This is
2313 * always a superclass or implemented interface of
2314 * site's class.
2315 */
2316 Symbol findInheritedMemberType(Env<AttrContext> env,
2317 Type site,
2318 Name name,
2319 TypeSymbol c) {
2320 Symbol bestSoFar = typeNotFound;
2321 Symbol sym;
2322 Type st = types.supertype(c.type);
2323 if (st != null && st.hasTag(CLASS)) {
2324 sym = findMemberType(env, site, name, st.tsym);
2325 bestSoFar = bestOf(bestSoFar, sym);
2326 }
2327 for (List<Type> l = types.interfaces(c.type);
2328 bestSoFar.kind != AMBIGUOUS && l.nonEmpty();
2329 l = l.tail) {
2330 sym = findMemberType(env, site, name, l.head.tsym);
2331 if (!bestSoFar.kind.isResolutionError() &&
2332 !sym.kind.isResolutionError() &&
2333 sym.owner != bestSoFar.owner)
2334 bestSoFar = new AmbiguityError(bestSoFar, sym);
2335 else
2336 bestSoFar = bestOf(bestSoFar, sym);
2337 }
2338 return bestSoFar;
2339 }
2340
2341 /** Find qualified member type.
2342 * @param env The current environment.
2343 * @param site The original type from where the selection takes
2344 * place.
2345 * @param name The type's name.
2346 * @param c The class to search for the member type. This is
2347 * always a superclass or implemented interface of
2348 * site's class.
2349 */
2350 Symbol findMemberType(Env<AttrContext> env,
2351 Type site,
2352 Name name,
2353 TypeSymbol c) {
2354 Symbol sym = findImmediateMemberType(env, site, name, c);
2355
2356 if (sym != typeNotFound)
2357 return sym;
2358
2359 return findInheritedMemberType(env, site, name, c);
2360
2361 }
2362
2363 /** Find a global type in given scope and load corresponding class.
2364 * @param env The current environment.
2365 * @param scope The scope in which to look for the type.
2366 * @param name The type's name.
2367 */
2368 Symbol findGlobalType(Env<AttrContext> env, Scope scope, Name name, RecoveryLoadClass recoveryLoadClass) {
2369 Symbol bestSoFar = typeNotFound;
2370 for (Symbol s : scope.getSymbolsByName(name)) {
2371 Symbol sym = loadClass(env, s.flatName(), recoveryLoadClass);
2372 if (bestSoFar.kind == TYP && sym.kind == TYP &&
2373 bestSoFar != sym)
2374 return new AmbiguityError(bestSoFar, sym);
2375 else
2376 bestSoFar = bestOf(bestSoFar, sym);
2377 }
2378 return bestSoFar;
2379 }
2380
2381 Symbol findTypeVar(Env<AttrContext> env, Name name, boolean staticOnly) {
2382 for (Symbol sym : env.info.scope.getSymbolsByName(name)) {
2383 if (sym.kind == TYP) {
2384 if (sym.type.hasTag(TYPEVAR) &&
2385 (staticOnly || (isStatic(env) && sym.owner.kind == TYP)))
2386 // if staticOnly is set, it means that we have recursed through a static declaration,
2387 // so type variable symbols should not be accessible. If staticOnly is unset, but
2388 // we are in a static declaration (field or method), we should not allow type-variables
2389 // defined in the enclosing class to "leak" into this context.
2390 return new StaticError(sym);
2391 return sym;
2392 }
2393 }
2394 return typeNotFound;
2395 }
2396
2397 /** Find an unqualified type symbol.
2398 * @param env The current environment.
2399 * @param name The type's name.
2400 */
2401 Symbol findType(Env<AttrContext> env, Name name) {
2402 if (name == names.empty)
2403 return typeNotFound; // do not allow inadvertent "lookup" of anonymous types
2404 Symbol bestSoFar = typeNotFound;
2405 Symbol sym;
2406 boolean staticOnly = false;
2407 for (Env<AttrContext> env1 = env; env1.outer != null; env1 = env1.outer) {
2408 // First, look for a type variable and the first member type
2409 final Symbol tyvar = findTypeVar(env1, name, staticOnly);
2410 if (isStatic(env1)) staticOnly = true;
2411 sym = findImmediateMemberType(env1, env1.enclClass.sym.type,
2412 name, env1.enclClass.sym);
2413
2414 // Return the type variable if we have it, and have no
2415 // immediate member, OR the type variable is for a method.
2416 if (tyvar != typeNotFound) {
2417 if (env.baseClause || sym == typeNotFound ||
2418 (tyvar.kind == TYP && tyvar.exists() &&
2419 tyvar.owner.kind == MTH)) {
2420 return tyvar;
2421 }
2422 }
2423
2424 // If the environment is a class def, finish up,
2425 // otherwise, do the entire findMemberType
2426 if (sym == typeNotFound)
2427 sym = findInheritedMemberType(env1, env1.enclClass.sym.type,
2428 name, env1.enclClass.sym);
2429
2430 if (staticOnly && sym.kind == TYP &&
2431 sym.type.hasTag(CLASS) &&
2432 sym.type.getEnclosingType().hasTag(CLASS) &&
2433 env1.enclClass.sym.type.isParameterized() &&
2434 sym.type.getEnclosingType().isParameterized())
2435 return new StaticError(sym);
2436 else if (sym.exists()) return sym;
2437 else bestSoFar = bestOf(bestSoFar, sym);
2438
2439 JCClassDecl encl = env1.baseClause ? (JCClassDecl)env1.tree : env1.enclClass;
2440 if ((encl.sym.flags() & STATIC) != 0)
2441 staticOnly = true;
2442 }
2443
2444 if (!env.tree.hasTag(IMPORT)) {
2445 sym = findGlobalType(env, env.toplevel.namedImportScope, name, namedImportScopeRecovery);
2446 if (sym.exists()) return sym;
2447 else bestSoFar = bestOf(bestSoFar, sym);
2448
2449 sym = findGlobalType(env, env.toplevel.toplevelScope, name, noRecovery);
2450 if (sym.exists()) return sym;
2451 else bestSoFar = bestOf(bestSoFar, sym);
2452
2453 sym = findGlobalType(env, env.toplevel.packge.members(), name, noRecovery);
2454 if (sym.exists()) return sym;
2455 else bestSoFar = bestOf(bestSoFar, sym);
2456
2457 sym = findGlobalType(env, env.toplevel.starImportScope, name, starImportScopeRecovery);
2458 if (sym.exists()) return sym;
2459 else bestSoFar = bestOf(bestSoFar, sym);
2460
2461 sym = findGlobalType(env, env.toplevel.moduleImportScope, name, moduleImportScopeRecovery);
2462 if (sym.exists()) return sym;
2463
2464 else bestSoFar = bestOf(bestSoFar, sym);
2465 }
2466
2467 return bestSoFar;
2468 }
2469
2470 /** Find an unqualified identifier which matches a specified kind set.
2471 * @param pos position on which report warnings, if any;
2472 * null warnings should not be reported
2473 * @param env The current environment.
2474 * @param name The identifier's name.
2475 * @param kind Indicates the possible symbol kinds
2476 * (a subset of VAL, TYP, PCK).
2477 */
2478 Symbol findIdent(DiagnosticPosition pos, Env<AttrContext> env, Name name, KindSelector kind) {
2479 try {
2480 return checkNonExistentType(checkRestrictedType(pos, findIdentInternal(pos, env, name, kind), name));
2481 } catch (ClassFinder.BadClassFile err) {
2482 return new BadClassFileError(err);
2483 } catch (CompletionFailure cf) {
2484 chk.completionError(pos, cf);
2485 return typeNotFound;
2486 }
2487 }
2488
2489 Symbol findIdentInternal(DiagnosticPosition pos, Env<AttrContext> env, Name name, KindSelector kind) {
2490 Symbol bestSoFar = typeNotFound;
2491 Symbol sym;
2492
2493 if (kind.contains(KindSelector.VAL)) {
2494 sym = findVar(pos, env, name);
2495 if (sym.exists()) return sym;
2496 else bestSoFar = bestOf(bestSoFar, sym);
2497 }
2498
2499 if (kind.contains(KindSelector.TYP)) {
2500 sym = findType(env, name);
2501 if (sym.exists()) return sym;
2502 else bestSoFar = bestOf(bestSoFar, sym);
2503 }
2504
2505 if (kind.contains(KindSelector.PCK))
2506 return lookupPackage(env, name);
2507 else return bestSoFar;
2508 }
2509
2510 /** Find an identifier in a package which matches a specified kind set.
2511 * @param pos position on which report warnings, if any;
2512 * null warnings should not be reported
2513 * @param env The current environment.
2514 * @param name The identifier's name.
2515 * @param kind Indicates the possible symbol kinds
2516 * (a nonempty subset of TYP, PCK).
2517 */
2518 Symbol findIdentInPackage(DiagnosticPosition pos,
2519 Env<AttrContext> env, TypeSymbol pck,
2520 Name name, KindSelector kind) {
2521 return checkNonExistentType(checkRestrictedType(pos, findIdentInPackageInternal(env, pck, name, kind), name));
2522 }
2523
2524 Symbol findIdentInPackageInternal(Env<AttrContext> env, TypeSymbol pck,
2525 Name name, KindSelector kind) {
2526 Name fullname = TypeSymbol.formFullName(name, pck);
2527 Symbol bestSoFar = typeNotFound;
2528 if (kind.contains(KindSelector.TYP)) {
2529 RecoveryLoadClass recoveryLoadClass =
2530 allowModules && !kind.contains(KindSelector.PCK) &&
2531 !pck.exists() && !env.info.attributionMode.isSpeculative ?
2532 doRecoveryLoadClass : noRecovery;
2533 Symbol sym = loadClass(env, fullname, recoveryLoadClass);
2534 if (sym.exists()) {
2535 // don't allow programs to use flatnames
2536 if (name == sym.name) return sym;
2537 }
2538 else bestSoFar = bestOf(bestSoFar, sym);
2539 }
2540 if (kind.contains(KindSelector.PCK)) {
2541 return lookupPackage(env, fullname);
2542 }
2543 return bestSoFar;
2544 }
2545
2546 /** Find an identifier among the members of a given type `site'.
2547 * @param pos position on which report warnings, if any;
2548 * null warnings should not be reported
2549 * @param env The current environment.
2550 * @param site The type containing the symbol to be found.
2551 * @param name The identifier's name.
2552 * @param kind Indicates the possible symbol kinds
2553 * (a subset of VAL, TYP).
2554 */
2555 Symbol findIdentInType(DiagnosticPosition pos,
2556 Env<AttrContext> env, Type site,
2557 Name name, KindSelector kind) {
2558 try {
2559 return checkNonExistentType(checkRestrictedType(pos, findIdentInTypeInternal(env, site, name, kind), name));
2560 } catch (ClassFinder.BadClassFile err) {
2561 return new BadClassFileError(err);
2562 } catch (CompletionFailure cf) {
2563 chk.completionError(pos, cf);
2564 return typeNotFound;
2565 }
2566 }
2567
2568 private Symbol checkNonExistentType(Symbol symbol) {
2569 /* Guard against returning a type is not on the class path of the current compilation,
2570 * but *was* on the class path of a separate compilation that produced a class file
2571 * that is on the class path of the current compilation. Such a type will fail completion
2572 * but the completion failure may have been silently swallowed (e.g. missing annotation types)
2573 * with an error stub symbol lingering in the symbol tables.
2574 */
2575 return symbol instanceof ClassSymbol c && c.type.isErroneous() && c.classfile == null ? typeNotFound : symbol;
2576 }
2577
2578 Symbol findIdentInTypeInternal(Env<AttrContext> env, Type site,
2579 Name name, KindSelector kind) {
2580 Symbol bestSoFar = typeNotFound;
2581 Symbol sym;
2582 if (kind.contains(KindSelector.VAL)) {
2583 sym = findField(env, site, name, site.tsym);
2584 if (sym.exists()) return sym;
2585 else bestSoFar = bestOf(bestSoFar, sym);
2586 }
2587
2588 if (kind.contains(KindSelector.TYP)) {
2589 sym = findMemberType(env, site, name, site.tsym);
2590 if (sym.exists()) return sym;
2591 else bestSoFar = bestOf(bestSoFar, sym);
2592 }
2593 return bestSoFar;
2594 }
2595
2596 private Symbol checkRestrictedType(DiagnosticPosition pos, Symbol bestSoFar, Name name) {
2597 if (bestSoFar.kind == TYP || bestSoFar.kind == ABSENT_TYP) {
2598 if (allowLocalVariableTypeInference && name.equals(names.var)) {
2599 bestSoFar = new BadRestrictedTypeError(names.var);
2600 } else if (name.equals(names.yield)) {
2601 if (allowYieldStatement) {
2602 bestSoFar = new BadRestrictedTypeError(names.yield);
2603 } else if (pos != null) {
2604 log.warning(pos, Warnings.IllegalRefToRestrictedType(names.yield));
2605 }
2606 }
2607 }
2608 return bestSoFar;
2609 }
2610
2611 /* ***************************************************************************
2612 * Access checking
2613 * The following methods convert ResolveErrors to ErrorSymbols, issuing
2614 * an error message in the process
2615 ****************************************************************************/
2616
2617 /** If `sym' is a bad symbol: report error and return errSymbol
2618 * else pass through unchanged,
2619 * additional arguments duplicate what has been used in trying to find the
2620 * symbol {@literal (--> flyweight pattern)}. This improves performance since we
2621 * expect misses to happen frequently.
2622 *
2623 * @param sym The symbol that was found, or a ResolveError.
2624 * @param pos The position to use for error reporting.
2625 * @param location The symbol the served as a context for this lookup
2626 * @param site The original type from where the selection took place.
2627 * @param name The symbol's name.
2628 * @param qualified Did we get here through a qualified expression resolution?
2629 * @param argtypes The invocation's value arguments,
2630 * if we looked for a method.
2631 * @param typeargtypes The invocation's type arguments,
2632 * if we looked for a method.
2633 * @param logResolveHelper helper class used to log resolve errors
2634 */
2635 Symbol accessInternal(Symbol sym,
2636 DiagnosticPosition pos,
2637 Symbol location,
2638 Type site,
2639 Name name,
2640 boolean qualified,
2641 List<Type> argtypes,
2642 List<Type> typeargtypes,
2643 LogResolveHelper logResolveHelper) {
2644 if (sym.kind.isResolutionError()) {
2645 ResolveError errSym = (ResolveError)sym.baseSymbol();
2646 sym = errSym.access(name, qualified ? site.tsym : syms.noSymbol);
2647 argtypes = logResolveHelper.getArgumentTypes(errSym, sym, name, argtypes);
2648 if (logResolveHelper.resolveDiagnosticNeeded(site, argtypes, typeargtypes)) {
2649 logResolveError(errSym, pos, location, site, name, argtypes, typeargtypes);
2650 }
2651 }
2652 return sym;
2653 }
2654
2655 /**
2656 * Variant of the generalized access routine, to be used for generating method
2657 * resolution diagnostics
2658 */
2659 Symbol accessMethod(Symbol sym,
2660 DiagnosticPosition pos,
2661 Symbol location,
2662 Type site,
2663 Name name,
2664 boolean qualified,
2665 List<Type> argtypes,
2666 List<Type> typeargtypes) {
2667 return accessInternal(sym, pos, location, site, name, qualified, argtypes, typeargtypes, methodLogResolveHelper);
2668 }
2669
2670 /** Same as original accessMethod(), but without location.
2671 */
2672 Symbol accessMethod(Symbol sym,
2673 DiagnosticPosition pos,
2674 Type site,
2675 Name name,
2676 boolean qualified,
2677 List<Type> argtypes,
2678 List<Type> typeargtypes) {
2679 return accessMethod(sym, pos, site.tsym, site, name, qualified, argtypes, typeargtypes);
2680 }
2681
2682 /**
2683 * Variant of the generalized access routine, to be used for generating variable,
2684 * type resolution diagnostics
2685 */
2686 Symbol accessBase(Symbol sym,
2687 DiagnosticPosition pos,
2688 Symbol location,
2689 Type site,
2690 Name name,
2691 boolean qualified) {
2692 return accessInternal(sym, pos, location, site, name, qualified, List.nil(), null, basicLogResolveHelper);
2693 }
2694
2695 /** Same as original accessBase(), but without location.
2696 */
2697 Symbol accessBase(Symbol sym,
2698 DiagnosticPosition pos,
2699 Type site,
2700 Name name,
2701 boolean qualified) {
2702 return accessBase(sym, pos, site.tsym, site, name, qualified);
2703 }
2704
2705 interface LogResolveHelper {
2706 boolean resolveDiagnosticNeeded(Type site, List<Type> argtypes, List<Type> typeargtypes);
2707 List<Type> getArgumentTypes(ResolveError errSym, Symbol accessedSym, Name name, List<Type> argtypes);
2708 }
2709
2710 LogResolveHelper basicLogResolveHelper = new LogResolveHelper() {
2711 public boolean resolveDiagnosticNeeded(Type site, List<Type> argtypes, List<Type> typeargtypes) {
2712 return !site.isErroneous();
2713 }
2714 public List<Type> getArgumentTypes(ResolveError errSym, Symbol accessedSym, Name name, List<Type> argtypes) {
2715 return argtypes;
2716 }
2717 };
2718
2719 LogResolveHelper silentLogResolveHelper = new LogResolveHelper() {
2720 public boolean resolveDiagnosticNeeded(Type site, List<Type> argtypes, List<Type> typeargtypes) {
2721 return false;
2722 }
2723 public List<Type> getArgumentTypes(ResolveError errSym, Symbol accessedSym, Name name, List<Type> argtypes) {
2724 return argtypes;
2725 }
2726 };
2727
2728 LogResolveHelper methodLogResolveHelper = new LogResolveHelper() {
2729 public boolean resolveDiagnosticNeeded(Type site, List<Type> argtypes, List<Type> typeargtypes) {
2730 return !site.isErroneous() &&
2731 !Type.isErroneous(argtypes) &&
2732 (typeargtypes == null || !Type.isErroneous(typeargtypes));
2733 }
2734 public List<Type> getArgumentTypes(ResolveError errSym, Symbol accessedSym, Name name, List<Type> argtypes) {
2735 return argtypes.map(new ResolveDeferredRecoveryMap(AttrMode.SPECULATIVE, accessedSym, currentResolutionContext.step));
2736 }
2737 };
2738
2739 class ResolveDeferredRecoveryMap extends DeferredAttr.RecoveryDeferredTypeMap {
2740
2741 public ResolveDeferredRecoveryMap(AttrMode mode, Symbol msym, MethodResolutionPhase step) {
2742 deferredAttr.super(mode, msym, step);
2743 }
2744
2745 @Override
2746 protected Type typeOf(DeferredType dt, Type pt) {
2747 Type res = super.typeOf(dt, pt);
2748 if (!res.isErroneous()) {
2749 switch (TreeInfo.skipParens(dt.tree).getTag()) {
2750 case LAMBDA:
2751 case REFERENCE:
2752 return dt;
2753 case CONDEXPR:
2754 return res == Type.recoveryType ?
2755 dt : res;
2756 }
2757 }
2758 return res;
2759 }
2760 }
2761
2762 /** Check that sym is not an abstract method.
2763 */
2764 void checkNonAbstract(DiagnosticPosition pos, Symbol sym) {
2765 if ((sym.flags() & ABSTRACT) != 0 && (sym.flags() & DEFAULT) == 0)
2766 log.error(pos,
2767 Errors.AbstractCantBeAccessedDirectly(kindName(sym),sym, sym.location()));
2768 }
2769
2770 /* ***************************************************************************
2771 * Name resolution
2772 * Naming conventions are as for symbol lookup
2773 * Unlike the find... methods these methods will report access errors
2774 ****************************************************************************/
2775
2776 /** Resolve an unqualified (non-method) identifier.
2777 * @param pos The position to use for error reporting.
2778 * @param env The environment current at the identifier use.
2779 * @param name The identifier's name.
2780 * @param kind The set of admissible symbol kinds for the identifier.
2781 */
2782 Symbol resolveIdent(DiagnosticPosition pos, Env<AttrContext> env,
2783 Name name, KindSelector kind) {
2784 return accessBase(
2785 findIdent(pos, env, name, kind),
2786 pos, env.enclClass.sym.type, name, false);
2787 }
2788
2789 /** Resolve an unqualified method identifier.
2790 * @param pos The position to use for error reporting.
2791 * @param env The environment current at the method invocation.
2792 * @param name The identifier's name.
2793 * @param argtypes The types of the invocation's value arguments.
2794 * @param typeargtypes The types of the invocation's type arguments.
2795 */
2796 Symbol resolveMethod(DiagnosticPosition pos,
2797 Env<AttrContext> env,
2798 Name name,
2799 List<Type> argtypes,
2800 List<Type> typeargtypes) {
2801 return lookupMethod(env, pos, env.enclClass.sym, resolveMethodCheck,
2802 new BasicLookupHelper(name, env.enclClass.sym.type, argtypes, typeargtypes) {
2803 @Override
2804 Symbol lookup(Env<AttrContext> env, MethodResolutionPhase phase) {
2805 return findFun(env, name, argtypes, typeargtypes,
2806 phase.isBoxingRequired(),
2807 phase.isVarargsRequired());
2808 }});
2809 }
2810
2811 /** Resolve a qualified method identifier
2812 * @param pos The position to use for error reporting.
2813 * @param env The environment current at the method invocation.
2814 * @param site The type of the qualifying expression, in which
2815 * identifier is searched.
2816 * @param name The identifier's name.
2817 * @param argtypes The types of the invocation's value arguments.
2818 * @param typeargtypes The types of the invocation's type arguments.
2819 */
2820 Symbol resolveQualifiedMethod(DiagnosticPosition pos, Env<AttrContext> env,
2821 Type site, Name name, List<Type> argtypes,
2822 List<Type> typeargtypes) {
2823 return resolveQualifiedMethod(pos, env, site.tsym, site, name, argtypes, typeargtypes);
2824 }
2825 Symbol resolveQualifiedMethod(DiagnosticPosition pos, Env<AttrContext> env,
2826 Symbol location, Type site, Name name, List<Type> argtypes,
2827 List<Type> typeargtypes) {
2828 return resolveQualifiedMethod(new MethodResolutionContext(), pos, env, location, site, name, argtypes, typeargtypes);
2829 }
2830 private Symbol resolveQualifiedMethod(MethodResolutionContext resolveContext,
2831 DiagnosticPosition pos, Env<AttrContext> env,
2832 Symbol location, Type site, Name name, List<Type> argtypes,
2833 List<Type> typeargtypes) {
2834 return lookupMethod(env, pos, location, resolveContext, new BasicLookupHelper(name, site, argtypes, typeargtypes) {
2835 @Override
2836 Symbol lookup(Env<AttrContext> env, MethodResolutionPhase phase) {
2837 return findMethod(env, site, name, argtypes, typeargtypes,
2838 phase.isBoxingRequired(),
2839 phase.isVarargsRequired());
2840 }
2841 @Override
2842 Symbol access(Env<AttrContext> env, DiagnosticPosition pos, Symbol location, Symbol sym) {
2843 if (sym.kind.isResolutionError()) {
2844 sym = super.access(env, pos, location, sym);
2845 } else {
2846 MethodSymbol msym = (MethodSymbol)sym;
2847 if ((msym.flags() & SIGNATURE_POLYMORPHIC) != 0) {
2848 env.info.pendingResolutionPhase = BASIC;
2849 return findPolymorphicSignatureInstance(env, sym, argtypes);
2850 }
2851 }
2852 return sym;
2853 }
2854 });
2855 }
2856
2857 /** Find or create an implicit method of exactly the given type (after erasure).
2858 * Searches in a side table, not the main scope of the site.
2859 * This emulates the lookup process required by JSR 292 in JVM.
2860 * @param env Attribution environment
2861 * @param spMethod signature polymorphic method - i.e. MH.invokeExact
2862 * @param argtypes The required argument types
2863 */
2864 Symbol findPolymorphicSignatureInstance(Env<AttrContext> env,
2865 final Symbol spMethod,
2866 List<Type> argtypes) {
2867 Type mtype = infer.instantiatePolymorphicSignatureInstance(env,
2868 (MethodSymbol)spMethod, currentResolutionContext, argtypes);
2869 return findPolymorphicSignatureInstance(spMethod, mtype);
2870 }
2871
2872 Symbol findPolymorphicSignatureInstance(final Symbol spMethod,
2873 Type mtype) {
2874 for (Symbol sym : polymorphicSignatureScope.getSymbolsByName(spMethod.name)) {
2875 // Check that there is already a method symbol for the method
2876 // type and owner
2877 if (types.isSameType(mtype, sym.type) &&
2878 spMethod.owner == sym.owner) {
2879 return sym;
2880 }
2881 }
2882
2883 Type spReturnType = spMethod.asType().getReturnType();
2884 if (types.isSameType(spReturnType, syms.objectType)) {
2885 // Polymorphic return, pass through mtype
2886 } else if (!types.isSameType(spReturnType, mtype.getReturnType())) {
2887 // Retain the sig poly method's return type, which differs from that of mtype
2888 // Will result in an incompatible return type error
2889 mtype = new MethodType(mtype.getParameterTypes(),
2890 spReturnType,
2891 mtype.getThrownTypes(),
2892 syms.methodClass);
2893 }
2894
2895 // Create the desired method
2896 // Retain static modifier is to support invocations to
2897 // MethodHandle.linkTo* methods
2898 long flags = ABSTRACT | HYPOTHETICAL |
2899 spMethod.flags() & (Flags.AccessFlags | Flags.STATIC);
2900 Symbol msym = new MethodSymbol(flags, spMethod.name, mtype, spMethod.owner) {
2901 @Override
2902 public Symbol baseSymbol() {
2903 return spMethod;
2904 }
2905 };
2906 if (!mtype.isErroneous()) { // Cache only if kosher.
2907 polymorphicSignatureScope.enter(msym);
2908 }
2909 return msym;
2910 }
2911
2912 /** Resolve a qualified method identifier, throw a fatal error if not
2913 * found.
2914 * @param pos The position to use for error reporting.
2915 * @param env The environment current at the method invocation.
2916 * @param site The type of the qualifying expression, in which
2917 * identifier is searched.
2918 * @param name The identifier's name.
2919 * @param argtypes The types of the invocation's value arguments.
2920 * @param typeargtypes The types of the invocation's type arguments.
2921 */
2922 public MethodSymbol resolveInternalMethod(DiagnosticPosition pos, Env<AttrContext> env,
2923 Type site, Name name,
2924 List<Type> argtypes,
2925 List<Type> typeargtypes) {
2926 MethodResolutionContext resolveContext = new MethodResolutionContext();
2927 resolveContext.internalResolution = true;
2928 Symbol sym = resolveQualifiedMethod(resolveContext, pos, env, site.tsym,
2929 site, name, argtypes, typeargtypes);
2930 if (sym.kind == MTH) return (MethodSymbol)sym;
2931 else throw new FatalError(
2932 diags.fragment(Fragments.FatalErrCantLocateMeth(name)));
2933 }
2934
2935 /** Resolve constructor.
2936 * @param pos The position to use for error reporting.
2937 * @param env The environment current at the constructor invocation.
2938 * @param site The type of class for which a constructor is searched.
2939 * @param argtypes The types of the constructor invocation's value
2940 * arguments.
2941 * @param typeargtypes The types of the constructor invocation's type
2942 * arguments.
2943 */
2944 Symbol resolveConstructor(DiagnosticPosition pos,
2945 Env<AttrContext> env,
2946 Type site,
2947 List<Type> argtypes,
2948 List<Type> typeargtypes) {
2949 return resolveConstructor(new MethodResolutionContext(), pos, env, site, argtypes, typeargtypes);
2950 }
2951
2952 private Symbol resolveConstructor(MethodResolutionContext resolveContext,
2953 final DiagnosticPosition pos,
2954 Env<AttrContext> env,
2955 Type site,
2956 List<Type> argtypes,
2957 List<Type> typeargtypes) {
2958 return lookupMethod(env, pos, site.tsym, resolveContext, new BasicLookupHelper(names.init, site, argtypes, typeargtypes) {
2959 @Override
2960 Symbol lookup(Env<AttrContext> env, MethodResolutionPhase phase) {
2961 return findConstructor(pos, env, site, argtypes, typeargtypes,
2962 phase.isBoxingRequired(),
2963 phase.isVarargsRequired());
2964 }
2965 });
2966 }
2967
2968 /** Resolve a constructor, throw a fatal error if not found.
2969 * @param pos The position to use for error reporting.
2970 * @param env The environment current at the method invocation.
2971 * @param site The type to be constructed.
2972 * @param argtypes The types of the invocation's value arguments.
2973 * @param typeargtypes The types of the invocation's type arguments.
2974 */
2975 public MethodSymbol resolveInternalConstructor(DiagnosticPosition pos, Env<AttrContext> env,
2976 Type site,
2977 List<Type> argtypes,
2978 List<Type> typeargtypes) {
2979 MethodResolutionContext resolveContext = new MethodResolutionContext();
2980 resolveContext.internalResolution = true;
2981 Symbol sym = resolveConstructor(resolveContext, pos, env, site, argtypes, typeargtypes);
2982 if (sym.kind == MTH) return (MethodSymbol)sym;
2983 else throw new FatalError(
2984 diags.fragment(Fragments.FatalErrCantLocateCtor(site)));
2985 }
2986
2987 Symbol findConstructor(DiagnosticPosition pos, Env<AttrContext> env,
2988 Type site, List<Type> argtypes,
2989 List<Type> typeargtypes,
2990 boolean allowBoxing,
2991 boolean useVarargs) {
2992 Symbol sym = findMethod(env, site,
2993 names.init, argtypes,
2994 typeargtypes, allowBoxing,
2995 useVarargs);
2996 chk.checkDeprecated(pos, env.info.scope.owner, sym);
2997 chk.checkPreview(pos, env.info.scope.owner, sym);
2998 return sym;
2999 }
3000
3001 /** Resolve constructor using diamond inference.
3002 * @param pos The position to use for error reporting.
3003 * @param env The environment current at the constructor invocation.
3004 * @param site The type of class for which a constructor is searched.
3005 * The scope of this class has been touched in attribution.
3006 * @param argtypes The types of the constructor invocation's value
3007 * arguments.
3008 * @param typeargtypes The types of the constructor invocation's type
3009 * arguments.
3010 */
3011 Symbol resolveDiamond(DiagnosticPosition pos,
3012 Env<AttrContext> env,
3013 Type site,
3014 List<Type> argtypes,
3015 List<Type> typeargtypes) {
3016 return lookupMethod(env, pos, site.tsym, resolveMethodCheck,
3017 new BasicLookupHelper(names.init, site, argtypes, typeargtypes) {
3018 @Override
3019 Symbol lookup(Env<AttrContext> env, MethodResolutionPhase phase) {
3020 return findDiamond(pos, env, site, argtypes, typeargtypes,
3021 phase.isBoxingRequired(),
3022 phase.isVarargsRequired());
3023 }
3024 @Override
3025 Symbol access(Env<AttrContext> env, DiagnosticPosition pos, Symbol location, Symbol sym) {
3026 if (sym.kind.isResolutionError()) {
3027 if (sym.kind != WRONG_MTH &&
3028 sym.kind != WRONG_MTHS) {
3029 sym = super.access(env, pos, location, sym);
3030 } else {
3031 sym = new DiamondError(sym, currentResolutionContext);
3032 sym = accessMethod(sym, pos, site, names.init, true, argtypes, typeargtypes);
3033 env.info.pendingResolutionPhase = currentResolutionContext.step;
3034 }
3035 }
3036 return sym;
3037 }});
3038 }
3039
3040 /** Find the constructor using diamond inference and do some checks(deprecated and preview).
3041 * @param pos The position to use for error reporting.
3042 * @param env The environment current at the constructor invocation.
3043 * @param site The type of class for which a constructor is searched.
3044 * The scope of this class has been touched in attribution.
3045 * @param argtypes The types of the constructor invocation's value arguments.
3046 * @param typeargtypes The types of the constructor invocation's type arguments.
3047 * @param allowBoxing Allow boxing conversions of arguments.
3048 * @param useVarargs Box trailing arguments into an array for varargs.
3049 */
3050 private Symbol findDiamond(DiagnosticPosition pos,
3051 Env<AttrContext> env,
3052 Type site,
3053 List<Type> argtypes,
3054 List<Type> typeargtypes,
3055 boolean allowBoxing,
3056 boolean useVarargs) {
3057 Symbol sym = findDiamond(env, site, argtypes, typeargtypes, allowBoxing, useVarargs);
3058 chk.checkDeprecated(pos, env.info.scope.owner, sym);
3059 chk.checkPreview(pos, env.info.scope.owner, sym);
3060 return sym;
3061 }
3062
3063 /** This method scans all the constructor symbol in a given class scope -
3064 * assuming that the original scope contains a constructor of the kind:
3065 * {@code Foo(X x, Y y)}, where X,Y are class type-variables declared in Foo,
3066 * a method check is executed against the modified constructor type:
3067 * {@code <X,Y>Foo<X,Y>(X x, Y y)}. This is crucial in order to enable diamond
3068 * inference. The inferred return type of the synthetic constructor IS
3069 * the inferred type for the diamond operator.
3070 */
3071 private Symbol findDiamond(Env<AttrContext> env,
3072 Type site,
3073 List<Type> argtypes,
3074 List<Type> typeargtypes,
3075 boolean allowBoxing,
3076 boolean useVarargs) {
3077 Symbol bestSoFar = methodNotFound;
3078 TypeSymbol tsym = site.tsym.isInterface() ? syms.objectType.tsym : site.tsym;
3079 for (final Symbol sym : tsym.members().getSymbolsByName(names.init)) {
3080 //- System.out.println(" e " + e.sym);
3081 if (sym.kind == MTH &&
3082 (sym.flags_field & SYNTHETIC) == 0) {
3083 List<Type> oldParams = sym.type.hasTag(FORALL) ?
3084 ((ForAll)sym.type).tvars :
3085 List.nil();
3086 Type constrType = new ForAll(site.tsym.type.getTypeArguments().appendList(oldParams),
3087 types.createMethodTypeWithReturn(sym.type.asMethodType(), site));
3088 MethodSymbol newConstr = new MethodSymbol(sym.flags(), names.init, constrType, site.tsym) {
3089 @Override
3090 public Symbol baseSymbol() {
3091 return sym;
3092 }
3093 };
3094 bestSoFar = selectBest(env, site, argtypes, typeargtypes,
3095 newConstr,
3096 bestSoFar,
3097 allowBoxing,
3098 useVarargs);
3099 }
3100 }
3101 return bestSoFar;
3102 }
3103
3104 Symbol getMemberReference(DiagnosticPosition pos,
3105 Env<AttrContext> env,
3106 JCMemberReference referenceTree,
3107 Type site,
3108 Name name) {
3109
3110 site = types.capture(site);
3111
3112 ReferenceLookupHelper lookupHelper = makeReferenceLookupHelper(
3113 referenceTree, site, name, List.nil(), null, VARARITY);
3114
3115 Env<AttrContext> newEnv = env.dup(env.tree, env.info.dup());
3116 Symbol sym = lookupMethod(newEnv, env.tree.pos(), site.tsym,
3117 nilMethodCheck, lookupHelper);
3118
3119 env.info.pendingResolutionPhase = newEnv.info.pendingResolutionPhase;
3120
3121 return sym;
3122 }
3123
3124 ReferenceLookupHelper makeReferenceLookupHelper(JCMemberReference referenceTree,
3125 Type site,
3126 Name name,
3127 List<Type> argtypes,
3128 List<Type> typeargtypes,
3129 MethodResolutionPhase maxPhase) {
3130 if (!name.equals(names.init)) {
3131 //method reference
3132 return new MethodReferenceLookupHelper(referenceTree, name, site, argtypes, typeargtypes, maxPhase);
3133 } else if (site.hasTag(ARRAY)) {
3134 //array constructor reference
3135 return new ArrayConstructorReferenceLookupHelper(referenceTree, site, argtypes, typeargtypes, maxPhase);
3136 } else {
3137 //class constructor reference
3138 return new ConstructorReferenceLookupHelper(referenceTree, site, argtypes, typeargtypes, maxPhase);
3139 }
3140 }
3141
3142 /**
3143 * Resolution of member references is typically done as a single
3144 * overload resolution step, where the argument types A are inferred from
3145 * the target functional descriptor.
3146 *
3147 * If the member reference is a method reference with a type qualifier,
3148 * a two-step lookup process is performed. The first step uses the
3149 * expected argument list A, while the second step discards the first
3150 * type from A (which is treated as a receiver type).
3151 *
3152 * There are two cases in which inference is performed: (i) if the member
3153 * reference is a constructor reference and the qualifier type is raw - in
3154 * which case diamond inference is used to infer a parameterization for the
3155 * type qualifier; (ii) if the member reference is an unbound reference
3156 * where the type qualifier is raw - in that case, during the unbound lookup
3157 * the receiver argument type is used to infer an instantiation for the raw
3158 * qualifier type.
3159 *
3160 * When a multi-step resolution process is exploited, the process of picking
3161 * the resulting symbol is delegated to an helper class {@link com.sun.tools.javac.comp.Resolve.ReferenceChooser}.
3162 *
3163 * This routine returns a pair (T,S), where S is the member reference symbol,
3164 * and T is the type of the class in which S is defined. This is necessary as
3165 * the type T might be dynamically inferred (i.e. if constructor reference
3166 * has a raw qualifier).
3167 */
3168 Pair<Symbol, ReferenceLookupHelper> resolveMemberReference(Env<AttrContext> env,
3169 JCMemberReference referenceTree,
3170 Type site,
3171 Name name,
3172 List<Type> argtypes,
3173 List<Type> typeargtypes,
3174 Type descriptor,
3175 MethodCheck methodCheck,
3176 InferenceContext inferenceContext,
3177 ReferenceChooser referenceChooser) {
3178
3179 //step 1 - bound lookup
3180 ReferenceLookupHelper boundLookupHelper = makeReferenceLookupHelper(
3181 referenceTree, site, name, argtypes, typeargtypes, VARARITY);
3182 Env<AttrContext> boundEnv = env.dup(env.tree, env.info.dup());
3183 MethodResolutionContext boundSearchResolveContext = new MethodResolutionContext();
3184 boundSearchResolveContext.methodCheck = methodCheck;
3185 Symbol boundSym = lookupMethod(boundEnv, env.tree.pos(),
3186 site.tsym, boundSearchResolveContext, boundLookupHelper);
3187 boolean isStaticSelector = TreeInfo.isStaticSelector(referenceTree.expr, names);
3188 ReferenceLookupResult boundRes = new ReferenceLookupResult(boundSym, boundSearchResolveContext, isStaticSelector);
3189 if (dumpMethodReferenceSearchResults) {
3190 dumpMethodReferenceSearchResults(referenceTree, boundSearchResolveContext, boundSym, true);
3191 }
3192
3193 //step 2 - unbound lookup
3194 Symbol unboundSym = methodNotFound;
3195 Env<AttrContext> unboundEnv = env.dup(env.tree, env.info.dup());
3196 ReferenceLookupHelper unboundLookupHelper = boundLookupHelper.unboundLookup(inferenceContext);
3197 ReferenceLookupResult unboundRes = referenceNotFound;
3198 if (unboundLookupHelper != null) {
3199 MethodResolutionContext unboundSearchResolveContext =
3200 new MethodResolutionContext();
3201 unboundSearchResolveContext.methodCheck = methodCheck;
3202 unboundSym = lookupMethod(unboundEnv, env.tree.pos(),
3203 site.tsym, unboundSearchResolveContext, unboundLookupHelper);
3204 unboundRes = new ReferenceLookupResult(unboundSym, unboundSearchResolveContext, isStaticSelector);
3205 if (dumpMethodReferenceSearchResults) {
3206 dumpMethodReferenceSearchResults(referenceTree, unboundSearchResolveContext, unboundSym, false);
3207 }
3208 }
3209
3210 //merge results
3211 Pair<Symbol, ReferenceLookupHelper> res;
3212 ReferenceLookupResult bestRes = referenceChooser.result(boundRes, unboundRes);
3213 res = new Pair<>(bestRes.sym,
3214 bestRes == unboundRes ? unboundLookupHelper : boundLookupHelper);
3215 env.info.pendingResolutionPhase = bestRes == unboundRes ?
3216 unboundEnv.info.pendingResolutionPhase :
3217 boundEnv.info.pendingResolutionPhase;
3218
3219 if (!res.fst.kind.isResolutionError()) {
3220 //handle sigpoly method references
3221 MethodSymbol msym = (MethodSymbol)res.fst;
3222 if ((msym.flags() & SIGNATURE_POLYMORPHIC) != 0) {
3223 env.info.pendingResolutionPhase = BASIC;
3224 res = new Pair<>(findPolymorphicSignatureInstance(msym, descriptor), res.snd);
3225 }
3226 }
3227
3228 return res;
3229 }
3230
3231 private void dumpMethodReferenceSearchResults(JCMemberReference referenceTree,
3232 MethodResolutionContext resolutionContext,
3233 Symbol bestSoFar,
3234 boolean bound) {
3235 ListBuffer<JCDiagnostic> subDiags = new ListBuffer<>();
3236 int pos = 0;
3237 int mostSpecificPos = -1;
3238 for (Candidate c : resolutionContext.candidates) {
3239 if (resolutionContext.step != c.step || !c.isApplicable()) {
3240 continue;
3241 } else {
3242 JCDiagnostic subDiag = null;
3243 if (c.sym.type.hasTag(FORALL)) {
3244 subDiag = diags.fragment(Fragments.PartialInstSig(c.mtype));
3245 }
3246
3247 String key = subDiag == null ?
3248 "applicable.method.found.2" :
3249 "applicable.method.found.3";
3250 subDiags.append(diags.fragment(key, pos,
3251 c.sym.isStatic() ? Fragments.Static : Fragments.NonStatic, c.sym, subDiag));
3252 if (c.sym == bestSoFar)
3253 mostSpecificPos = pos;
3254 pos++;
3255 }
3256 }
3257 JCDiagnostic main = diags.note(
3258 log.currentSource(),
3259 referenceTree,
3260 "method.ref.search.results.multi",
3261 bound ? Fragments.Bound : Fragments.Unbound,
3262 referenceTree.toString(), mostSpecificPos);
3263 JCDiagnostic d = new JCDiagnostic.MultilineDiagnostic(main, subDiags.toList());
3264 log.report(d);
3265 }
3266
3267 /**
3268 * This class is used to represent a method reference lookup result. It keeps track of two
3269 * things: (i) the symbol found during a method reference lookup and (ii) the static kind
3270 * of the lookup (see {@link com.sun.tools.javac.comp.Resolve.ReferenceLookupResult.StaticKind}).
3271 */
3272 static class ReferenceLookupResult {
3273
3274 /**
3275 * Static kind associated with a method reference lookup. Erroneous lookups end up with
3276 * the UNDEFINED kind; successful lookups will end up with either STATIC, NON_STATIC,
3277 * depending on whether all applicable candidates are static or non-static methods,
3278 * respectively. If a successful lookup has both static and non-static applicable methods,
3279 * its kind is set to BOTH.
3280 */
3281 enum StaticKind {
3282 STATIC,
3283 NON_STATIC,
3284 BOTH,
3285 UNDEFINED;
3286
3287 /**
3288 * Retrieve the static kind associated with a given (method) symbol.
3289 */
3290 static StaticKind from(Symbol s) {
3291 return s.isStatic() ?
3292 STATIC : NON_STATIC;
3293 }
3294
3295 /**
3296 * Merge two static kinds together.
3297 */
3298 static StaticKind reduce(StaticKind sk1, StaticKind sk2) {
3299 if (sk1 == UNDEFINED) {
3300 return sk2;
3301 } else if (sk2 == UNDEFINED) {
3302 return sk1;
3303 } else {
3304 return sk1 == sk2 ? sk1 : BOTH;
3305 }
3306 }
3307 }
3308
3309 /** The static kind. */
3310 StaticKind staticKind;
3311
3312 /** The lookup result. */
3313 Symbol sym;
3314
3315 ReferenceLookupResult(Symbol sym, MethodResolutionContext resolutionContext, boolean isStaticSelector) {
3316 this(sym, staticKind(sym, resolutionContext, isStaticSelector));
3317 }
3318
3319 private ReferenceLookupResult(Symbol sym, StaticKind staticKind) {
3320 this.staticKind = staticKind;
3321 this.sym = sym;
3322 }
3323
3324 private static StaticKind staticKind(Symbol sym, MethodResolutionContext resolutionContext, boolean isStaticSelector) {
3325 if (sym.kind == MTH && !isStaticSelector) {
3326 return StaticKind.from(sym);
3327 } else if (sym.kind == MTH || sym.kind == AMBIGUOUS) {
3328 return resolutionContext.candidates.stream()
3329 .filter(c -> c.isApplicable() && c.step == resolutionContext.step)
3330 .map(c -> StaticKind.from(c.sym))
3331 .reduce(StaticKind::reduce)
3332 .orElse(StaticKind.UNDEFINED);
3333 } else {
3334 return StaticKind.UNDEFINED;
3335 }
3336 }
3337
3338 /**
3339 * Does this result corresponds to a successful lookup (i.e. one where a method has been found?)
3340 */
3341 boolean isSuccess() {
3342 return staticKind != StaticKind.UNDEFINED;
3343 }
3344
3345 /**
3346 * Does this result have given static kind?
3347 */
3348 boolean hasKind(StaticKind sk) {
3349 return this.staticKind == sk;
3350 }
3351
3352 /**
3353 * Error recovery helper: can this lookup result be ignored (for the purpose of returning
3354 * some 'better' result) ?
3355 */
3356 boolean canIgnore() {
3357 switch (sym.kind) {
3358 case ABSENT_MTH:
3359 return true;
3360 case WRONG_MTH:
3361 InapplicableSymbolError errSym =
3362 (InapplicableSymbolError)sym.baseSymbol();
3363 return new Template(MethodCheckDiag.ARITY_MISMATCH.regex())
3364 .matches(errSym.errCandidate().snd);
3365 case WRONG_MTHS:
3366 InapplicableSymbolsError errSyms =
3367 (InapplicableSymbolsError)sym.baseSymbol();
3368 return errSyms.filterCandidates(errSyms.mapCandidates()).isEmpty();
3369 default:
3370 return false;
3371 }
3372 }
3373
3374 static ReferenceLookupResult error(Symbol sym) {
3375 return new ReferenceLookupResult(sym, StaticKind.UNDEFINED);
3376 }
3377 }
3378
3379 /**
3380 * This abstract class embodies the logic that converts one (bound lookup) or two (unbound lookup)
3381 * {@code ReferenceLookupResult} objects into a {@code Symbol}, which is then regarded as the
3382 * result of method reference resolution.
3383 */
3384 abstract class ReferenceChooser {
3385 /**
3386 * Generate a result from a pair of lookup result objects. This method delegates to the
3387 * appropriate result generation routine.
3388 */
3389 ReferenceLookupResult result(ReferenceLookupResult boundRes, ReferenceLookupResult unboundRes) {
3390 return unboundRes != referenceNotFound ?
3391 unboundResult(boundRes, unboundRes) :
3392 boundResult(boundRes);
3393 }
3394
3395 /**
3396 * Generate a symbol from a given bound lookup result.
3397 */
3398 abstract ReferenceLookupResult boundResult(ReferenceLookupResult boundRes);
3399
3400 /**
3401 * Generate a symbol from a pair of bound/unbound lookup results.
3402 */
3403 abstract ReferenceLookupResult unboundResult(ReferenceLookupResult boundRes, ReferenceLookupResult unboundRes);
3404 }
3405
3406 /**
3407 * This chooser implements the selection strategy used during a full lookup; this logic
3408 * is described in JLS SE 8 (15.3.2).
3409 */
3410 ReferenceChooser basicReferenceChooser = new ReferenceChooser() {
3411
3412 @Override
3413 ReferenceLookupResult boundResult(ReferenceLookupResult boundRes) {
3414 return !boundRes.isSuccess() || boundRes.hasKind(StaticKind.NON_STATIC) ?
3415 boundRes : //the search produces a non-static method
3416 ReferenceLookupResult.error(new BadMethodReferenceError(boundRes.sym, false));
3417 }
3418
3419 @Override
3420 ReferenceLookupResult unboundResult(ReferenceLookupResult boundRes, ReferenceLookupResult unboundRes) {
3421 if (boundRes.isSuccess() && boundRes.sym.isStatic() &&
3422 (!unboundRes.isSuccess() || unboundRes.hasKind(StaticKind.STATIC))) {
3423 //the first search produces a static method and no non-static method is applicable
3424 //during the second search
3425 return boundRes;
3426 } else if (unboundRes.isSuccess() && !unboundRes.sym.isStatic() &&
3427 (!boundRes.isSuccess() || boundRes.hasKind(StaticKind.NON_STATIC))) {
3428 //the second search produces a non-static method and no static method is applicable
3429 //during the first search
3430 return unboundRes;
3431 } else if (boundRes.isSuccess() && unboundRes.isSuccess()) {
3432 //both searches produce some result; ambiguity (error recovery)
3433 return ReferenceLookupResult.error(ambiguityError(boundRes.sym, unboundRes.sym));
3434 } else if (boundRes.isSuccess() || unboundRes.isSuccess()) {
3435 //Both searches failed to produce a result with correct staticness (i.e. first search
3436 //produces an non-static method). Alternatively, a given search produced a result
3437 //with the right staticness, but the other search has applicable methods with wrong
3438 //staticness (error recovery)
3439 return ReferenceLookupResult.error(new BadMethodReferenceError(boundRes.isSuccess() ?
3440 boundRes.sym : unboundRes.sym, true));
3441 } else {
3442 //both searches fail to produce a result - pick 'better' error using heuristics (error recovery)
3443 return (boundRes.canIgnore() && !unboundRes.canIgnore()) ?
3444 unboundRes : boundRes;
3445 }
3446 }
3447 };
3448
3449 /**
3450 * This chooser implements the selection strategy used during an arity-based lookup; this logic
3451 * is described in JLS SE 8 (15.12.2.1).
3452 */
3453 ReferenceChooser structuralReferenceChooser = new ReferenceChooser() {
3454
3455 @Override
3456 ReferenceLookupResult boundResult(ReferenceLookupResult boundRes) {
3457 return (!boundRes.isSuccess() || !boundRes.hasKind(StaticKind.STATIC)) ?
3458 boundRes : //the search has at least one applicable non-static method
3459 ReferenceLookupResult.error(new BadMethodReferenceError(boundRes.sym, false));
3460 }
3461
3462 @Override
3463 ReferenceLookupResult unboundResult(ReferenceLookupResult boundRes, ReferenceLookupResult unboundRes) {
3464 if (boundRes.isSuccess() && !boundRes.hasKind(StaticKind.NON_STATIC)) {
3465 //the first search has at least one applicable static method
3466 return boundRes;
3467 } else if (unboundRes.isSuccess() && !unboundRes.hasKind(StaticKind.STATIC)) {
3468 //the second search has at least one applicable non-static method
3469 return unboundRes;
3470 } else if (boundRes.isSuccess() || unboundRes.isSuccess()) {
3471 //either the first search produces a non-static method, or second search produces
3472 //a non-static method (error recovery)
3473 return ReferenceLookupResult.error(new BadMethodReferenceError(boundRes.isSuccess() ?
3474 boundRes.sym : unboundRes.sym, true));
3475 } else {
3476 //both searches fail to produce a result - pick 'better' error using heuristics (error recovery)
3477 return (boundRes.canIgnore() && !unboundRes.canIgnore()) ?
3478 unboundRes : boundRes;
3479 }
3480 }
3481 };
3482
3483 /**
3484 * Helper for defining custom method-like lookup logic; a lookup helper
3485 * provides hooks for (i) the actual lookup logic and (ii) accessing the
3486 * lookup result (this step might result in compiler diagnostics to be generated)
3487 */
3488 abstract class LookupHelper {
3489
3490 /** name of the symbol to lookup */
3491 Name name;
3492
3493 /** location in which the lookup takes place */
3494 Type site;
3495
3496 /** actual types used during the lookup */
3497 List<Type> argtypes;
3498
3499 /** type arguments used during the lookup */
3500 List<Type> typeargtypes;
3501
3502 /** Max overload resolution phase handled by this helper */
3503 MethodResolutionPhase maxPhase;
3504
3505 LookupHelper(Name name, Type site, List<Type> argtypes, List<Type> typeargtypes, MethodResolutionPhase maxPhase) {
3506 this.name = name;
3507 this.site = site;
3508 this.argtypes = argtypes;
3509 this.typeargtypes = typeargtypes;
3510 this.maxPhase = maxPhase;
3511 }
3512
3513 /**
3514 * Should lookup stop at given phase with given result
3515 */
3516 final boolean shouldStop(Symbol sym, MethodResolutionPhase phase) {
3517 return phase.ordinal() > maxPhase.ordinal() ||
3518 !sym.kind.isResolutionError() || sym.kind == AMBIGUOUS || sym.kind == STATICERR;
3519 }
3520
3521 /**
3522 * Search for a symbol under a given overload resolution phase - this method
3523 * is usually called several times, once per each overload resolution phase
3524 */
3525 abstract Symbol lookup(Env<AttrContext> env, MethodResolutionPhase phase);
3526
3527 /**
3528 * Dump overload resolution info
3529 */
3530 void debug(DiagnosticPosition pos, Symbol sym) {
3531 //do nothing
3532 }
3533
3534 /**
3535 * Validate the result of the lookup
3536 */
3537 abstract Symbol access(Env<AttrContext> env, DiagnosticPosition pos, Symbol location, Symbol sym);
3538 }
3539
3540 abstract class BasicLookupHelper extends LookupHelper {
3541
3542 BasicLookupHelper(Name name, Type site, List<Type> argtypes, List<Type> typeargtypes) {
3543 this(name, site, argtypes, typeargtypes, MethodResolutionPhase.VARARITY);
3544 }
3545
3546 BasicLookupHelper(Name name, Type site, List<Type> argtypes, List<Type> typeargtypes, MethodResolutionPhase maxPhase) {
3547 super(name, site, argtypes, typeargtypes, maxPhase);
3548 }
3549
3550 @Override
3551 Symbol access(Env<AttrContext> env, DiagnosticPosition pos, Symbol location, Symbol sym) {
3552 if (sym.kind.isResolutionError()) {
3553 //if nothing is found return the 'first' error
3554 sym = accessMethod(sym, pos, location, site, name, true, argtypes, typeargtypes);
3555 }
3556 return sym;
3557 }
3558
3559 @Override
3560 void debug(DiagnosticPosition pos, Symbol sym) {
3561 reportVerboseResolutionDiagnostic(pos, name, site, argtypes, typeargtypes, sym);
3562 }
3563 }
3564
3565 /**
3566 * Helper class for member reference lookup. A reference lookup helper
3567 * defines the basic logic for member reference lookup; a method gives
3568 * access to an 'unbound' helper used to perform an unbound member
3569 * reference lookup.
3570 */
3571 abstract class ReferenceLookupHelper extends LookupHelper {
3572
3573 /** The member reference tree */
3574 JCMemberReference referenceTree;
3575
3576 ReferenceLookupHelper(JCMemberReference referenceTree, Name name, Type site,
3577 List<Type> argtypes, List<Type> typeargtypes, MethodResolutionPhase maxPhase) {
3578 super(name, site, argtypes, typeargtypes, maxPhase);
3579 this.referenceTree = referenceTree;
3580 }
3581
3582 /**
3583 * Returns an unbound version of this lookup helper. By default, this
3584 * method returns an dummy lookup helper.
3585 */
3586 ReferenceLookupHelper unboundLookup(InferenceContext inferenceContext) {
3587 return null;
3588 }
3589
3590 /**
3591 * Get the kind of the member reference
3592 */
3593 abstract JCMemberReference.ReferenceKind referenceKind(Symbol sym);
3594
3595 Symbol access(Env<AttrContext> env, DiagnosticPosition pos, Symbol location, Symbol sym) {
3596 //skip error reporting
3597 return sym;
3598 }
3599 }
3600
3601 /**
3602 * Helper class for method reference lookup. The lookup logic is based
3603 * upon Resolve.findMethod; in certain cases, this helper class has a
3604 * corresponding unbound helper class (see UnboundMethodReferenceLookupHelper).
3605 * In such cases, non-static lookup results are thrown away.
3606 */
3607 class MethodReferenceLookupHelper extends ReferenceLookupHelper {
3608
3609 /** The original method reference lookup site. */
3610 Type originalSite;
3611
3612 MethodReferenceLookupHelper(JCMemberReference referenceTree, Name name, Type site,
3613 List<Type> argtypes, List<Type> typeargtypes, MethodResolutionPhase maxPhase) {
3614 super(referenceTree, name, types.skipTypeVars(site, true), argtypes, typeargtypes, maxPhase);
3615 this.originalSite = site;
3616 }
3617
3618 @Override
3619 final Symbol lookup(Env<AttrContext> env, MethodResolutionPhase phase) {
3620 return findMethod(env, site, name, argtypes, typeargtypes,
3621 phase.isBoxingRequired(), phase.isVarargsRequired());
3622 }
3623
3624 @Override
3625 ReferenceLookupHelper unboundLookup(InferenceContext inferenceContext) {
3626 if (TreeInfo.isStaticSelector(referenceTree.expr, names)) {
3627 if (argtypes.nonEmpty() &&
3628 (argtypes.head.hasTag(NONE) ||
3629 types.isSubtypeUnchecked(inferenceContext.asUndetVar(argtypes.head), originalSite))) {
3630 return new UnboundMethodReferenceLookupHelper(referenceTree, name,
3631 originalSite, argtypes, typeargtypes, maxPhase);
3632 } else {
3633 return new ReferenceLookupHelper(referenceTree, name, site, argtypes, typeargtypes, maxPhase) {
3634 @Override
3635 ReferenceLookupHelper unboundLookup(InferenceContext inferenceContext) {
3636 return this;
3637 }
3638
3639 @Override
3640 Symbol lookup(Env<AttrContext> env, MethodResolutionPhase phase) {
3641 return methodNotFound;
3642 }
3643
3644 @Override
3645 ReferenceKind referenceKind(Symbol sym) {
3646 Assert.error();
3647 return null;
3648 }
3649 };
3650 }
3651 } else {
3652 return super.unboundLookup(inferenceContext);
3653 }
3654 }
3655
3656 @Override
3657 ReferenceKind referenceKind(Symbol sym) {
3658 if (sym.isStatic()) {
3659 return ReferenceKind.STATIC;
3660 } else {
3661 Name selName = TreeInfo.name(referenceTree.getQualifierExpression());
3662 return selName != null && selName == names._super ?
3663 ReferenceKind.SUPER :
3664 ReferenceKind.BOUND;
3665 }
3666 }
3667
3668 @Override
3669 Symbol access(Env<AttrContext> env, DiagnosticPosition pos, Symbol location, Symbol sym) {
3670 if (originalSite.hasTag(TYPEVAR) && sym.kind == MTH) {
3671 sym = (sym.flags() & Flags.PRIVATE) != 0 ?
3672 new AccessError(env, site, sym) :
3673 sym;
3674 return accessBase(sym, pos, location, originalSite, name, true);
3675 } else {
3676 return super.access(env, pos, location, sym);
3677 }
3678 }
3679 }
3680
3681 /**
3682 * Helper class for unbound method reference lookup. Essentially the same
3683 * as the basic method reference lookup helper; main difference is that static
3684 * lookup results are thrown away. If qualifier type is raw, an attempt to
3685 * infer a parameterized type is made using the first actual argument (that
3686 * would otherwise be ignored during the lookup).
3687 */
3688 class UnboundMethodReferenceLookupHelper extends MethodReferenceLookupHelper {
3689
3690 UnboundMethodReferenceLookupHelper(JCMemberReference referenceTree, Name name, Type site,
3691 List<Type> argtypes, List<Type> typeargtypes, MethodResolutionPhase maxPhase) {
3692 super(referenceTree, name, site, argtypes.tail, typeargtypes, maxPhase);
3693 if (site.isRaw() && !argtypes.head.hasTag(NONE)) {
3694 Type asSuperSite = types.asSuper(argtypes.head, site.tsym);
3695 this.site = types.skipTypeVars(asSuperSite, true);
3696 }
3697 }
3698
3699 @Override
3700 ReferenceLookupHelper unboundLookup(InferenceContext inferenceContext) {
3701 return this;
3702 }
3703
3704 @Override
3705 ReferenceKind referenceKind(Symbol sym) {
3706 return ReferenceKind.UNBOUND;
3707 }
3708 }
3709
3710 /**
3711 * Helper class for array constructor lookup; an array constructor lookup
3712 * is simulated by looking up a method that returns the array type specified
3713 * as qualifier, and that accepts a single int parameter (size of the array).
3714 */
3715 class ArrayConstructorReferenceLookupHelper extends ReferenceLookupHelper {
3716
3717 ArrayConstructorReferenceLookupHelper(JCMemberReference referenceTree, Type site, List<Type> argtypes,
3718 List<Type> typeargtypes, MethodResolutionPhase maxPhase) {
3719 super(referenceTree, names.init, site, argtypes, typeargtypes, maxPhase);
3720 }
3721
3722 @Override
3723 protected Symbol lookup(Env<AttrContext> env, MethodResolutionPhase phase) {
3724 WriteableScope sc = WriteableScope.create(syms.arrayClass);
3725 MethodSymbol arrayConstr = new MethodSymbol(PUBLIC, name, null, site.tsym);
3726 arrayConstr.type = new MethodType(List.of(syms.intType), site, List.nil(), syms.methodClass);
3727 sc.enter(arrayConstr);
3728 return findMethodInScope(env, site, name, argtypes, typeargtypes, sc, methodNotFound, phase.isBoxingRequired(), phase.isVarargsRequired(), false);
3729 }
3730
3731 @Override
3732 ReferenceKind referenceKind(Symbol sym) {
3733 return ReferenceKind.ARRAY_CTOR;
3734 }
3735 }
3736
3737 /**
3738 * Helper class for constructor reference lookup. The lookup logic is based
3739 * upon either Resolve.findMethod or Resolve.findDiamond - depending on
3740 * whether the constructor reference needs diamond inference (this is the case
3741 * if the qualifier type is raw). A special erroneous symbol is returned
3742 * if the lookup returns the constructor of an inner class and there's no
3743 * enclosing instance in scope.
3744 */
3745 class ConstructorReferenceLookupHelper extends ReferenceLookupHelper {
3746
3747 boolean needsInference;
3748
3749 ConstructorReferenceLookupHelper(JCMemberReference referenceTree, Type site, List<Type> argtypes,
3750 List<Type> typeargtypes, MethodResolutionPhase maxPhase) {
3751 super(referenceTree, names.init, site, argtypes, typeargtypes, maxPhase);
3752 if (site.isRaw()) {
3753 this.site = new ClassType(site.getEnclosingType(),
3754 !(site.tsym.isInner() && site.getEnclosingType().isRaw()) ?
3755 site.tsym.type.getTypeArguments() : List.nil(), site.tsym, site.getMetadata());
3756 needsInference = true;
3757 }
3758 }
3759
3760 @Override
3761 protected Symbol lookup(Env<AttrContext> env, MethodResolutionPhase phase) {
3762 return needsInference ?
3763 findDiamond(env, site, argtypes, typeargtypes, phase.isBoxingRequired(), phase.isVarargsRequired()) :
3764 findMethod(env, site, name, argtypes, typeargtypes,
3765 phase.isBoxingRequired(), phase.isVarargsRequired());
3766 }
3767
3768 @Override
3769 ReferenceKind referenceKind(Symbol sym) {
3770 return site.getEnclosingType().hasTag(NONE) ?
3771 ReferenceKind.TOPLEVEL : ReferenceKind.IMPLICIT_INNER;
3772 }
3773 }
3774
3775 /**
3776 * Main overload resolution routine. On each overload resolution step, a
3777 * lookup helper class is used to perform the method/constructor lookup;
3778 * at the end of the lookup, the helper is used to validate the results
3779 * (this last step might trigger overload resolution diagnostics).
3780 */
3781 Symbol lookupMethod(Env<AttrContext> env, DiagnosticPosition pos, Symbol location, MethodCheck methodCheck, LookupHelper lookupHelper) {
3782 MethodResolutionContext resolveContext = new MethodResolutionContext();
3783 resolveContext.methodCheck = methodCheck;
3784 return lookupMethod(env, pos, location, resolveContext, lookupHelper);
3785 }
3786
3787 Symbol lookupMethod(Env<AttrContext> env, DiagnosticPosition pos, Symbol location,
3788 MethodResolutionContext resolveContext, LookupHelper lookupHelper) {
3789 MethodResolutionContext prevResolutionContext = currentResolutionContext;
3790 try {
3791 Symbol bestSoFar = methodNotFound;
3792 currentResolutionContext = resolveContext;
3793 for (MethodResolutionPhase phase : methodResolutionSteps) {
3794 if (lookupHelper.shouldStop(bestSoFar, phase))
3795 break;
3796 MethodResolutionPhase prevPhase = currentResolutionContext.step;
3797 Symbol prevBest = bestSoFar;
3798 currentResolutionContext.step = phase;
3799 Symbol sym = lookupHelper.lookup(env, phase);
3800 lookupHelper.debug(pos, sym);
3801 bestSoFar = phase.mergeResults(bestSoFar, sym);
3802 env.info.pendingResolutionPhase = (prevBest == bestSoFar) ? prevPhase : phase;
3803 }
3804 return lookupHelper.access(env, pos, location, bestSoFar);
3805 } finally {
3806 currentResolutionContext = prevResolutionContext;
3807 }
3808 }
3809
3810 /**
3811 * Find a "valid" reference to an enclosing 'A.this' such that A is a subclass of the provided class symbol.
3812 * A reference to an enclosing 'A.this' is "valid" if (a) we're not in the early-construction context for A
3813 * and (b) if the current class is not an inner class of A.
3814 */
3815 Symbol findSelfContaining(DiagnosticPosition pos,
3816 Env<AttrContext> env,
3817 TypeSymbol c,
3818 boolean isSuper) {
3819 Env<AttrContext> env1 = isSuper ? env.outer : env;
3820 boolean staticOnly = false;
3821 while (env1.outer != null) {
3822 if (isStatic(env1)) staticOnly = true;
3823 if (env1.enclClass.sym.isSubClass(c, types)) {
3824 Symbol sym = env1.info.scope.findFirst(names._this);
3825 if (sym != null) {
3826 if (staticOnly) {
3827 // current class is not an inner class, stop search
3828 return new StaticError(sym);
3829 } else if (env1.info.ctorPrologue && !isAllowedEarlyReference(pos, env1, (VarSymbol)sym)) {
3830 // early construction context, stop search
3831 return new RefBeforeCtorCalledError(sym);
3832 } else {
3833 // found it
3834 return sym;
3835 }
3836 }
3837 }
3838 if ((env1.enclClass.sym.flags() & STATIC) != 0) staticOnly = true;
3839 env1 = env1.outer;
3840 }
3841 return varNotFound;
3842 }
3843
3844 /**
3845 * Resolve the (method) owner of a local class. This can fail if the local class
3846 * is referenced from a static context nested inside the local class. Effectively,
3847 * this lookup succeeds if we can access a local variable declared inside the owner
3848 * method from the provided env.
3849 */
3850 Symbol findLocalClassOwner(Env<AttrContext> env, TypeSymbol c) {
3851 Symbol owner = c.owner;
3852 Assert.check(owner.kind == MTH || owner.kind == VAR);
3853 Env<AttrContext> env1 = env;
3854 boolean staticOnly = false;
3855 while (env1.outer != null) {
3856 if (env1.info.scope.owner == owner) {
3857 return (staticOnly) ?
3858 new BadLocalClassCreation(c) :
3859 owner;
3860 }
3861 if (isStatic(env1)) staticOnly = true;
3862 env1 = env1.outer;
3863 }
3864 return owner.kind == MTH ?
3865 methodNotFound :
3866 varNotFound;
3867 }
3868
3869 /**
3870 * Resolve `c.name' where name == this or name == super.
3871 * @param pos The position to use for error reporting.
3872 * @param env The environment current at the expression.
3873 * @param c The qualifier.
3874 * @param name The identifier's name.
3875 */
3876 Symbol resolveSelf(DiagnosticPosition pos,
3877 Env<AttrContext> env,
3878 TypeSymbol c,
3879 Name name) {
3880 Assert.check(name == names._this || name == names._super);
3881 Env<AttrContext> env1 = env;
3882 boolean staticOnly = false;
3883 while (env1.outer != null) {
3884 if (isStatic(env1)) staticOnly = true;
3885 if (env1.enclClass.sym == c) {
3886 Symbol sym = env1.info.scope.findFirst(name);
3887 if (sym != null) {
3888 if (staticOnly)
3889 sym = new StaticError(sym);
3890 else if (env1.info.ctorPrologue && !isAllowedEarlyReference(pos, env1, (VarSymbol)sym))
3891 sym = new RefBeforeCtorCalledError(sym);
3892 return accessBase(sym, pos, env.enclClass.sym.type,
3893 name, true);
3894 }
3895 }
3896 if ((env1.enclClass.sym.flags() & STATIC) != 0) staticOnly = true;
3897 env1 = env1.outer;
3898 }
3899 if (c.isInterface() &&
3900 name == names._super && !isStatic(env) &&
3901 types.isDirectSuperInterface(c, env.enclClass.sym)) {
3902 //this might be a default super call if one of the superinterfaces is 'c'
3903 for (Type t : pruneInterfaces(env.enclClass.type)) {
3904 if (t.tsym == c) {
3905 if (env.info.ctorPrologue)
3906 log.error(pos, Errors.CantRefBeforeCtorCalled(name));
3907 env.info.defaultSuperCallSite = t;
3908 return new VarSymbol(0, names._super,
3909 types.asSuper(env.enclClass.type, c), env.enclClass.sym);
3910 }
3911 }
3912 //find a direct supertype that is a subtype of 'c'
3913 for (Type i : types.directSupertypes(env.enclClass.type)) {
3914 if (i.tsym.isSubClass(c, types) && i.tsym != c) {
3915 log.error(pos,
3916 Errors.IllegalDefaultSuperCall(c,
3917 Fragments.RedundantSupertype(c, i)));
3918 return syms.errSymbol;
3919 }
3920 }
3921 Assert.error();
3922 }
3923 log.error(pos, Errors.NotEnclClass(c));
3924 return syms.errSymbol;
3925 }
3926 //where
3927 private List<Type> pruneInterfaces(Type t) {
3928 ListBuffer<Type> result = new ListBuffer<>();
3929 for (Type t1 : types.interfaces(t)) {
3930 boolean shouldAdd = true;
3931 for (Type t2 : types.directSupertypes(t)) {
3932 if (t1 != t2 && !t2.hasTag(ERROR) && types.isSubtypeNoCapture(t2, t1)) {
3933 shouldAdd = false;
3934 }
3935 }
3936 if (shouldAdd) {
3937 result.append(t1);
3938 }
3939 }
3940 return result.toList();
3941 }
3942
3943 /**
3944 * Determine if an early instance field reference may appear in a constructor prologue.
3945 *
3946 * <p>
3947 * This is only allowed when:
3948 * - The field is being assigned a value (i.e., written but not read)
3949 * - The field is not inherited from a superclass
3950 * - The assignment is not within a lambda, because that would require
3951 * capturing 'this' which is not allowed prior to super().
3952 *
3953 * <p>
3954 * Note, this method doesn't catch all such scenarios, because this method
3955 * is invoked for symbol "x" only for "x = 42" but not for "this.x = 42".
3956 * We also don't verify that the field has no initializer, which is required.
3957 * To catch those cases, we rely on similar logic in Attr.checkAssignable().
3958 */
3959 private boolean isAllowedEarlyReference(DiagnosticPosition pos, Env<AttrContext> env, VarSymbol v) {
3960
3961 // Check assumptions
3962 Assert.check(env.info.ctorPrologue);
3963 Assert.check((v.flags_field & STATIC) == 0);
3964
3965 // The symbol must appear in the LHS of an assignment statement
3966 if (!(env.tree instanceof JCAssign assign))
3967 return false;
3968
3969 // The assignment statement must not be within a lambda
3970 if (env.info.isLambda)
3971 return false;
3972
3973 // Get the symbol's qualifier, if any
3974 JCExpression lhs = TreeInfo.skipParens(assign.lhs);
3975 JCExpression base;
3976 switch (lhs.getTag()) {
3977 case IDENT:
3978 base = null;
3979 break;
3980 case SELECT:
3981 JCFieldAccess select = (JCFieldAccess)lhs;
3982 base = select.selected;
3983 if (!TreeInfo.isExplicitThisReference(types, (ClassType)env.enclClass.type, base))
3984 return false;
3985 break;
3986 default:
3987 return false;
3988 }
3989
3990 // If an early reference, the field must not be declared in a superclass
3991 if (isEarlyReference(env, base, v) && v.owner != env.enclClass.sym)
3992 return false;
3993
3994 // The flexible constructors feature must be enabled
3995 preview.checkSourceLevel(pos, Feature.FLEXIBLE_CONSTRUCTORS);
3996
3997 // OK
3998 return true;
3999 }
4000
4001 /**
4002 * Determine if the variable appearance constitutes an early reference to the current class.
4003 *
4004 * <p>
4005 * This means the variable is an instance field of the current class and it appears
4006 * in an early initialization context of it (i.e., one of its constructor prologues).
4007 *
4008 * <p>
4009 * Such a reference is only allowed for assignments to non-initialized fields that are
4010 * not inherited from a superclass, though that is not enforced by this method.
4011 *
4012 * @param env The current environment
4013 * @param base Variable qualifier, if any, otherwise null
4014 * @param v The variable
4015 */
4016 public boolean isEarlyReference(Env<AttrContext> env, JCTree base, VarSymbol v) {
4017 return env.info.ctorPrologue &&
4018 (v.flags() & STATIC) == 0 &&
4019 v.owner.kind == TYP &&
4020 types.isSubtype(env.enclClass.type, v.owner.type) &&
4021 (base == null || TreeInfo.isExplicitThisReference(types, (ClassType)env.enclClass.type, base));
4022 }
4023
4024 /* ***************************************************************************
4025 * ResolveError classes, indicating error situations when accessing symbols
4026 ****************************************************************************/
4027
4028 //used by TransTypes when checking target type of synthetic cast
4029 public void logAccessErrorInternal(Env<AttrContext> env, JCTree tree, Type type) {
4030 AccessError error = new AccessError(env, env.enclClass.type, type.tsym);
4031 logResolveError(error, tree.pos(), env.enclClass.sym, env.enclClass.type, null, null, null);
4032 }
4033 //where
4034 private void logResolveError(ResolveError error,
4035 DiagnosticPosition pos,
4036 Symbol location,
4037 Type site,
4038 Name name,
4039 List<Type> argtypes,
4040 List<Type> typeargtypes) {
4041 JCDiagnostic d = error.getDiagnostic(JCDiagnostic.DiagnosticType.ERROR,
4042 pos, location, site, name, argtypes, typeargtypes);
4043 if (d != null) {
4044 d.setFlag(DiagnosticFlag.RESOLVE_ERROR);
4045 log.report(d);
4046 }
4047 }
4048
4049 private final LocalizedString noArgs = new LocalizedString("compiler.misc.no.args");
4050
4051 public Object methodArguments(List<Type> argtypes) {
4052 if (argtypes == null || argtypes.isEmpty()) {
4053 return noArgs;
4054 } else {
4055 ListBuffer<Object> diagArgs = new ListBuffer<>();
4056 for (Type t : argtypes) {
4057 if (t.hasTag(DEFERRED)) {
4058 diagArgs.append(((DeferredAttr.DeferredType)t).tree);
4059 } else {
4060 diagArgs.append(t);
4061 }
4062 }
4063 return diagArgs;
4064 }
4065 }
4066
4067 /** check if a type is a subtype of Serializable, if that is available.*/
4068 boolean isSerializable(Type t) {
4069 try {
4070 syms.serializableType.complete();
4071 }
4072 catch (CompletionFailure e) {
4073 return false;
4074 }
4075 return types.isSubtype(t, syms.serializableType);
4076 }
4077
4078 /**
4079 * Root class for resolution errors. Subclass of ResolveError
4080 * represent a different kinds of resolution error - as such they must
4081 * specify how they map into concrete compiler diagnostics.
4082 */
4083 abstract class ResolveError extends Symbol {
4084
4085 /** The name of the kind of error, for debugging only. */
4086 final String debugName;
4087
4088 ResolveError(Kind kind, String debugName) {
4089 super(kind, 0, null, null, null);
4090 this.debugName = debugName;
4091 }
4092
4093 @Override @DefinedBy(Api.LANGUAGE_MODEL)
4094 public <R, P> R accept(ElementVisitor<R, P> v, P p) {
4095 throw new AssertionError();
4096 }
4097
4098 @Override
4099 public String toString() {
4100 return debugName;
4101 }
4102
4103 @Override
4104 public boolean exists() {
4105 return false;
4106 }
4107
4108 @Override
4109 public boolean isStatic() {
4110 return false;
4111 }
4112
4113 /**
4114 * Create an external representation for this erroneous symbol to be
4115 * used during attribution - by default this returns the symbol of a
4116 * brand new error type which stores the original type found
4117 * during resolution.
4118 *
4119 * @param name the name used during resolution
4120 * @param location the location from which the symbol is accessed
4121 */
4122 protected Symbol access(Name name, TypeSymbol location) {
4123 return types.createErrorType(name, location, syms.errSymbol.type).tsym;
4124 }
4125
4126 /**
4127 * Create a diagnostic representing this resolution error.
4128 *
4129 * @param dkind The kind of the diagnostic to be created (e.g error).
4130 * @param pos The position to be used for error reporting.
4131 * @param site The original type from where the selection took place.
4132 * @param name The name of the symbol to be resolved.
4133 * @param argtypes The invocation's value arguments,
4134 * if we looked for a method.
4135 * @param typeargtypes The invocation's type arguments,
4136 * if we looked for a method.
4137 */
4138 abstract JCDiagnostic getDiagnostic(JCDiagnostic.DiagnosticType dkind,
4139 DiagnosticPosition pos,
4140 Symbol location,
4141 Type site,
4142 Name name,
4143 List<Type> argtypes,
4144 List<Type> typeargtypes);
4145 }
4146
4147 /**
4148 * This class is the root class of all resolution errors caused by
4149 * an invalid symbol being found during resolution.
4150 */
4151 abstract class InvalidSymbolError extends ResolveError {
4152
4153 /** The invalid symbol found during resolution */
4154 Symbol sym;
4155
4156 InvalidSymbolError(Kind kind, Symbol sym, String debugName) {
4157 super(kind, debugName);
4158 this.sym = sym;
4159 }
4160
4161 @Override
4162 public boolean exists() {
4163 return true;
4164 }
4165
4166 @Override
4167 public String toString() {
4168 return super.toString() + " wrongSym=" + sym;
4169 }
4170
4171 @Override
4172 public Symbol access(Name name, TypeSymbol location) {
4173 if (!sym.kind.isResolutionError() && sym.kind.matches(KindSelector.TYP))
4174 return types.createErrorType(name, location, sym.type).tsym;
4175 else
4176 return sym;
4177 }
4178 }
4179
4180 class BadRestrictedTypeError extends ResolveError {
4181 private final Name typeName;
4182 BadRestrictedTypeError(Name typeName) {
4183 super(Kind.BAD_RESTRICTED_TYPE, "bad var use");
4184 this.typeName = typeName;
4185 }
4186
4187 @Override
4188 JCDiagnostic getDiagnostic(DiagnosticType dkind, DiagnosticPosition pos, Symbol location, Type site, Name name, List<Type> argtypes, List<Type> typeargtypes) {
4189 return diags.create(dkind, log.currentSource(), pos, "illegal.ref.to.restricted.type", typeName);
4190 }
4191 }
4192
4193 /**
4194 * InvalidSymbolError error class indicating that a symbol matching a
4195 * given name does not exists in a given site.
4196 */
4197 class SymbolNotFoundError extends ResolveError {
4198
4199 SymbolNotFoundError(Kind kind) {
4200 this(kind, "symbol not found error");
4201 }
4202
4203 SymbolNotFoundError(Kind kind, String debugName) {
4204 super(kind, debugName);
4205 }
4206
4207 @Override
4208 JCDiagnostic getDiagnostic(JCDiagnostic.DiagnosticType dkind,
4209 DiagnosticPosition pos,
4210 Symbol location,
4211 Type site,
4212 Name name,
4213 List<Type> argtypes,
4214 List<Type> typeargtypes) {
4215 argtypes = argtypes == null ? List.nil() : argtypes;
4216 typeargtypes = typeargtypes == null ? List.nil() : typeargtypes;
4217 if (name == names.error)
4218 return null;
4219
4220 boolean hasLocation = false;
4221 if (location == null) {
4222 location = site.tsym;
4223 }
4224 if (!location.name.isEmpty()) {
4225 if (location.kind == PCK && !site.tsym.exists() && location.name != names.java) {
4226 return diags.create(dkind, log.currentSource(), pos,
4227 "doesnt.exist", location);
4228 }
4229 hasLocation = !location.name.equals(names._this) &&
4230 !location.name.equals(names._super);
4231 }
4232 boolean isConstructor = name == names.init;
4233 KindName kindname = isConstructor ? KindName.CONSTRUCTOR : kind.absentKind();
4234 Name idname = isConstructor ? site.tsym.name : name;
4235 String errKey = getErrorKey(kindname, typeargtypes.nonEmpty(), hasLocation);
4236 if (hasLocation) {
4237 return diags.create(dkind, log.currentSource(), pos,
4238 errKey, kindname, idname, //symbol kindname, name
4239 typeargtypes, args(argtypes), //type parameters and arguments (if any)
4240 getLocationDiag(location, site)); //location kindname, type
4241 }
4242 else {
4243 return diags.create(dkind, log.currentSource(), pos,
4244 errKey, kindname, idname, //symbol kindname, name
4245 typeargtypes, args(argtypes)); //type parameters and arguments (if any)
4246 }
4247 }
4248 //where
4249 private Object args(List<Type> args) {
4250 return args.isEmpty() ? args : methodArguments(args);
4251 }
4252
4253 private String getErrorKey(KindName kindname, boolean hasTypeArgs, boolean hasLocation) {
4254 String key = "cant.resolve";
4255 String suffix = hasLocation ? ".location" : "";
4256 switch (kindname) {
4257 case METHOD:
4258 case CONSTRUCTOR: {
4259 suffix += ".args";
4260 suffix += hasTypeArgs ? ".params" : "";
4261 }
4262 }
4263 return key + suffix;
4264 }
4265 private JCDiagnostic getLocationDiag(Symbol location, Type site) {
4266 if (location.kind == VAR) {
4267 return diags.fragment(Fragments.Location1(kindName(location),
4268 location,
4269 location.type));
4270 } else {
4271 return diags.fragment(Fragments.Location(typeKindName(site),
4272 site,
4273 null));
4274 }
4275 }
4276 }
4277
4278 /**
4279 * InvalidSymbolError error class indicating that a given symbol
4280 * (either a method, a constructor or an operand) is not applicable
4281 * given an actual arguments/type argument list.
4282 */
4283 class InapplicableSymbolError extends ResolveError {
4284
4285 protected MethodResolutionContext resolveContext;
4286
4287 InapplicableSymbolError(MethodResolutionContext context) {
4288 this(WRONG_MTH, "inapplicable symbol error", context);
4289 }
4290
4291 protected InapplicableSymbolError(Kind kind, String debugName, MethodResolutionContext context) {
4292 super(kind, debugName);
4293 this.resolveContext = context;
4294 }
4295
4296 @Override
4297 public String toString() {
4298 return super.toString();
4299 }
4300
4301 @Override
4302 public boolean exists() {
4303 return true;
4304 }
4305
4306 @Override
4307 JCDiagnostic getDiagnostic(JCDiagnostic.DiagnosticType dkind,
4308 DiagnosticPosition pos,
4309 Symbol location,
4310 Type site,
4311 Name name,
4312 List<Type> argtypes,
4313 List<Type> typeargtypes) {
4314 if (name == names.error)
4315 return null;
4316
4317 Pair<Symbol, JCDiagnostic> c = errCandidate();
4318 Symbol ws = c.fst.asMemberOf(site, types);
4319 UnaryOperator<JCDiagnostic> rewriter = compactMethodDiags ?
4320 d -> MethodResolutionDiagHelper.rewrite(diags, pos, log.currentSource(), dkind, c.snd) : null;
4321
4322 // If the problem is due to type arguments, then the method parameters aren't relevant,
4323 // so use the error message that omits them to avoid confusion.
4324 switch (c.snd.getCode()) {
4325 case "compiler.misc.wrong.number.type.args":
4326 case "compiler.misc.explicit.param.do.not.conform.to.bounds":
4327 return diags.create(dkind, log.currentSource(), pos,
4328 "cant.apply.symbol.noargs",
4329 rewriter,
4330 kindName(ws),
4331 ws.name == names.init ? ws.owner.name : ws.name,
4332 ws.owner.type,
4333 c.snd);
4334 default:
4335 // Avoid saying "constructor Array in class Array"
4336 if (ws.owner == syms.arrayClass && ws.name == names.init) {
4337 return diags.create(dkind, log.currentSource(), pos,
4338 "cant.apply.array.ctor",
4339 rewriter,
4340 methodArguments(ws.type.getParameterTypes()),
4341 methodArguments(argtypes),
4342 c.snd);
4343 }
4344 return diags.create(dkind, log.currentSource(), pos,
4345 "cant.apply.symbol",
4346 rewriter,
4347 kindName(ws),
4348 ws.name == names.init ? ws.owner.name : ws.name,
4349 methodArguments(ws.type.getParameterTypes()),
4350 methodArguments(argtypes),
4351 kindName(ws.owner),
4352 ws.owner.type,
4353 c.snd);
4354 }
4355 }
4356
4357 @Override
4358 public Symbol access(Name name, TypeSymbol location) {
4359 Pair<Symbol, JCDiagnostic> cand = errCandidate();
4360 TypeSymbol errSymbol = types.createErrorType(name, location, cand != null ? cand.fst.type : syms.errSymbol.type).tsym;
4361 if (cand != null) {
4362 attrRecover.wrongMethodSymbolCandidate(errSymbol, cand.fst, cand.snd);
4363 }
4364 return errSymbol;
4365 }
4366
4367 protected Pair<Symbol, JCDiagnostic> errCandidate() {
4368 Candidate bestSoFar = null;
4369 for (Candidate c : resolveContext.candidates) {
4370 if (c.isApplicable()) continue;
4371 bestSoFar = c;
4372 }
4373 Assert.checkNonNull(bestSoFar);
4374 return new Pair<>(bestSoFar.sym, bestSoFar.details);
4375 }
4376 }
4377
4378 /**
4379 * ResolveError error class indicating that a symbol (either methods, constructors or operand)
4380 * is not applicable given an actual arguments/type argument list.
4381 */
4382 class InapplicableSymbolsError extends InapplicableSymbolError {
4383
4384 InapplicableSymbolsError(MethodResolutionContext context) {
4385 super(WRONG_MTHS, "inapplicable symbols", context);
4386 }
4387
4388 @Override
4389 JCDiagnostic getDiagnostic(JCDiagnostic.DiagnosticType dkind,
4390 DiagnosticPosition pos,
4391 Symbol location,
4392 Type site,
4393 Name name,
4394 List<Type> argtypes,
4395 List<Type> typeargtypes) {
4396 Map<Symbol, JCDiagnostic> candidatesMap = mapCandidates();
4397 Map<Symbol, JCDiagnostic> filteredCandidates = compactMethodDiags ?
4398 filterCandidates(candidatesMap) :
4399 mapCandidates();
4400 if (filteredCandidates.isEmpty()) {
4401 filteredCandidates = candidatesMap;
4402 }
4403 boolean truncatedDiag = candidatesMap.size() != filteredCandidates.size();
4404 if (filteredCandidates.size() > 1) {
4405 JCDiagnostic err = diags.create(dkind,
4406 null,
4407 truncatedDiag ?
4408 EnumSet.of(DiagnosticFlag.COMPRESSED) :
4409 EnumSet.noneOf(DiagnosticFlag.class),
4410 log.currentSource(),
4411 pos,
4412 "cant.apply.symbols",
4413 name == names.init ? KindName.CONSTRUCTOR : kind.absentKind(),
4414 name == names.init ? site.tsym.name : name,
4415 methodArguments(argtypes));
4416 return new JCDiagnostic.MultilineDiagnostic(err, candidateDetails(filteredCandidates, site));
4417 } else if (filteredCandidates.size() == 1) {
4418 Map.Entry<Symbol, JCDiagnostic> _e =
4419 filteredCandidates.entrySet().iterator().next();
4420 final Pair<Symbol, JCDiagnostic> p = new Pair<>(_e.getKey(), _e.getValue());
4421 JCDiagnostic d = new InapplicableSymbolError(resolveContext) {
4422 @Override
4423 protected Pair<Symbol, JCDiagnostic> errCandidate() {
4424 return p;
4425 }
4426 }.getDiagnostic(dkind, pos,
4427 location, site, name, argtypes, typeargtypes);
4428 if (truncatedDiag) {
4429 d.setFlag(DiagnosticFlag.COMPRESSED);
4430 }
4431 return d;
4432 } else {
4433 return new SymbolNotFoundError(ABSENT_MTH).getDiagnostic(dkind, pos,
4434 location, site, name, argtypes, typeargtypes);
4435 }
4436 }
4437 //where
4438 private Map<Symbol, JCDiagnostic> mapCandidates() {
4439 MostSpecificMap candidates = new MostSpecificMap();
4440 for (Candidate c : resolveContext.candidates) {
4441 if (c.isApplicable()) continue;
4442 candidates.put(c);
4443 }
4444 return candidates;
4445 }
4446
4447 @SuppressWarnings("serial")
4448 private class MostSpecificMap extends LinkedHashMap<Symbol, JCDiagnostic> {
4449 private void put(Candidate c) {
4450 ListBuffer<Symbol> overridden = new ListBuffer<>();
4451 for (Symbol s : keySet()) {
4452 if (s == c.sym) {
4453 continue;
4454 }
4455 if (c.sym.overrides(s, (TypeSymbol)s.owner, types, false)) {
4456 overridden.add(s);
4457 } else if (s.overrides(c.sym, (TypeSymbol)c.sym.owner, types, false)) {
4458 return;
4459 }
4460 }
4461 for (Symbol s : overridden) {
4462 remove(s);
4463 }
4464 put(c.sym, c.details);
4465 }
4466 }
4467
4468 Map<Symbol, JCDiagnostic> filterCandidates(Map<Symbol, JCDiagnostic> candidatesMap) {
4469 Map<Symbol, JCDiagnostic> candidates = new LinkedHashMap<>();
4470 for (Map.Entry<Symbol, JCDiagnostic> _entry : candidatesMap.entrySet()) {
4471 JCDiagnostic d = _entry.getValue();
4472 if (!new Template(MethodCheckDiag.ARITY_MISMATCH.regex()).matches(d)) {
4473 candidates.put(_entry.getKey(), d);
4474 }
4475 }
4476 return candidates;
4477 }
4478
4479 private List<JCDiagnostic> candidateDetails(Map<Symbol, JCDiagnostic> candidatesMap, Type site) {
4480 List<JCDiagnostic> details = List.nil();
4481 for (Map.Entry<Symbol, JCDiagnostic> _entry : candidatesMap.entrySet()) {
4482 Symbol sym = _entry.getKey();
4483 JCDiagnostic detailDiag =
4484 diags.fragment(Fragments.InapplicableMethod(Kinds.kindName(sym),
4485 sym.location(site, types),
4486 sym.asMemberOf(site, types),
4487 _entry.getValue()));
4488 details = details.prepend(detailDiag);
4489 }
4490 //typically members are visited in reverse order (see Scope)
4491 //so we need to reverse the candidate list so that candidates
4492 //conform to source order
4493 return details;
4494 }
4495
4496 @Override
4497 protected Pair<Symbol, JCDiagnostic> errCandidate() {
4498 Map<Symbol, JCDiagnostic> candidatesMap = mapCandidates();
4499 Map<Symbol, JCDiagnostic> filteredCandidates = filterCandidates(candidatesMap);
4500 if (filteredCandidates.size() == 1) {
4501 return Pair.of(filteredCandidates.keySet().iterator().next(),
4502 filteredCandidates.values().iterator().next());
4503 }
4504 return null;
4505 }
4506 }
4507
4508 /**
4509 * DiamondError error class indicating that a constructor symbol is not applicable
4510 * given an actual arguments/type argument list using diamond inference.
4511 */
4512 class DiamondError extends InapplicableSymbolError {
4513
4514 Symbol sym;
4515
4516 public DiamondError(Symbol sym, MethodResolutionContext context) {
4517 super(sym.kind, "diamondError", context);
4518 this.sym = sym;
4519 }
4520
4521 JCDiagnostic getDetails() {
4522 return (sym.kind == WRONG_MTH) ?
4523 ((InapplicableSymbolError)sym.baseSymbol()).errCandidate().snd :
4524 null;
4525 }
4526
4527 @Override
4528 JCDiagnostic getDiagnostic(DiagnosticType dkind, DiagnosticPosition pos,
4529 Symbol location, Type site, Name name, List<Type> argtypes, List<Type> typeargtypes) {
4530 JCDiagnostic details = getDetails();
4531 if (details != null && compactMethodDiags) {
4532 JCDiagnostic simpleDiag =
4533 MethodResolutionDiagHelper.rewrite(diags, pos, log.currentSource(), dkind, details);
4534 if (simpleDiag != null) {
4535 return simpleDiag;
4536 }
4537 }
4538 String key = details == null ?
4539 "cant.apply.diamond" :
4540 "cant.apply.diamond.1";
4541 return diags.create(dkind, log.currentSource(), pos, key,
4542 Fragments.Diamond(site.tsym), details);
4543 }
4544 }
4545
4546 /**
4547 * An InvalidSymbolError error class indicating that a symbol is not
4548 * accessible from a given site
4549 */
4550 class AccessError extends InvalidSymbolError {
4551
4552 private Env<AttrContext> env;
4553 private Type site;
4554
4555 AccessError(Env<AttrContext> env, Type site, Symbol sym) {
4556 super(HIDDEN, sym, "access error");
4557 this.env = env;
4558 this.site = site;
4559 }
4560
4561 @Override
4562 public boolean exists() {
4563 return false;
4564 }
4565
4566 @Override
4567 JCDiagnostic getDiagnostic(JCDiagnostic.DiagnosticType dkind,
4568 DiagnosticPosition pos,
4569 Symbol location,
4570 Type site,
4571 Name name,
4572 List<Type> argtypes,
4573 List<Type> typeargtypes) {
4574 if (sym.name == names.init && sym.owner != site.tsym) {
4575 return new SymbolNotFoundError(ABSENT_MTH).getDiagnostic(dkind,
4576 pos, location, site, name, argtypes, typeargtypes);
4577 }
4578 else if ((sym.flags() & PUBLIC) != 0
4579 || (env != null && this.site != null
4580 && !isAccessible(env, this.site))) {
4581 if (sym.owner.kind == PCK) {
4582 return diags.create(dkind, log.currentSource(),
4583 pos, "not.def.access.package.cant.access",
4584 sym, sym.location(), inaccessiblePackageReason(env, sym.packge()));
4585 } else if ( sym.packge() != syms.rootPackage
4586 && !symbolPackageVisible(env, sym)) {
4587 return diags.create(dkind, log.currentSource(),
4588 pos, "not.def.access.class.intf.cant.access.reason",
4589 sym, sym.location(), sym.location().packge(),
4590 inaccessiblePackageReason(env, sym.packge()));
4591 } else {
4592 return diags.create(dkind, log.currentSource(),
4593 pos, "not.def.access.class.intf.cant.access",
4594 sym, sym.location());
4595 }
4596 }
4597 else if ((sym.flags() & (PRIVATE | PROTECTED)) != 0) {
4598 return diags.create(dkind, log.currentSource(),
4599 pos, "report.access", sym,
4600 asFlagSet(sym.flags() & (PRIVATE | PROTECTED)),
4601 sym.location());
4602 }
4603 else {
4604 return diags.create(dkind, log.currentSource(),
4605 pos, "not.def.public.cant.access", sym, sym.location());
4606 }
4607 }
4608
4609 private String toString(Type type) {
4610 StringBuilder sb = new StringBuilder();
4611 sb.append(type);
4612 if (type != null) {
4613 sb.append("[tsym:").append(type.tsym);
4614 if (type.tsym != null)
4615 sb.append("packge:").append(type.tsym.packge());
4616 sb.append("]");
4617 }
4618 return sb.toString();
4619 }
4620 }
4621
4622 class InvisibleSymbolError extends InvalidSymbolError {
4623
4624 private final Env<AttrContext> env;
4625 private final boolean suppressError;
4626
4627 InvisibleSymbolError(Env<AttrContext> env, boolean suppressError, Symbol sym) {
4628 super(HIDDEN, sym, "invisible class error");
4629 this.env = env;
4630 this.suppressError = suppressError;
4631 this.name = sym.name;
4632 }
4633
4634 @Override
4635 JCDiagnostic getDiagnostic(JCDiagnostic.DiagnosticType dkind,
4636 DiagnosticPosition pos,
4637 Symbol location,
4638 Type site,
4639 Name name,
4640 List<Type> argtypes,
4641 List<Type> typeargtypes) {
4642 if (suppressError)
4643 return null;
4644
4645 if (sym.kind == PCK) {
4646 JCDiagnostic details = inaccessiblePackageReason(env, sym.packge());
4647 return diags.create(dkind, log.currentSource(),
4648 pos, "package.not.visible", sym, details);
4649 }
4650
4651 JCDiagnostic details = inaccessiblePackageReason(env, sym.packge());
4652
4653 if (pos.getTree() != null) {
4654 Symbol o = sym;
4655 JCTree tree = pos.getTree();
4656
4657 while (o.kind != PCK && tree.hasTag(SELECT)) {
4658 o = o.owner;
4659 tree = ((JCFieldAccess) tree).selected;
4660 }
4661
4662 if (o.kind == PCK) {
4663 pos = tree.pos();
4664
4665 return diags.create(dkind, log.currentSource(),
4666 pos, "package.not.visible", o, details);
4667 }
4668 }
4669
4670 return diags.create(dkind, log.currentSource(),
4671 pos, "not.def.access.package.cant.access", sym, sym.packge(), details);
4672 }
4673 }
4674
4675 JCDiagnostic inaccessiblePackageReason(Env<AttrContext> env, PackageSymbol sym) {
4676 //no dependency:
4677 if (!env.toplevel.modle.readModules.contains(sym.modle)) {
4678 //does not read:
4679 if (sym.modle != syms.unnamedModule) {
4680 if (env.toplevel.modle != syms.unnamedModule) {
4681 return diags.fragment(Fragments.NotDefAccessDoesNotRead(env.toplevel.modle,
4682 sym,
4683 sym.modle));
4684 } else {
4685 return diags.fragment(Fragments.NotDefAccessDoesNotReadFromUnnamed(sym,
4686 sym.modle));
4687 }
4688 } else {
4689 return diags.fragment(Fragments.NotDefAccessDoesNotReadUnnamed(sym,
4690 env.toplevel.modle));
4691 }
4692 } else {
4693 if (sym.packge().modle.exports.stream().anyMatch(e -> e.packge == sym)) {
4694 //not exported to this module:
4695 if (env.toplevel.modle != syms.unnamedModule) {
4696 return diags.fragment(Fragments.NotDefAccessNotExportedToModule(sym,
4697 sym.modle,
4698 env.toplevel.modle));
4699 } else {
4700 return diags.fragment(Fragments.NotDefAccessNotExportedToModuleFromUnnamed(sym,
4701 sym.modle));
4702 }
4703 } else {
4704 //not exported:
4705 if (env.toplevel.modle != syms.unnamedModule) {
4706 return diags.fragment(Fragments.NotDefAccessNotExported(sym,
4707 sym.modle));
4708 } else {
4709 return diags.fragment(Fragments.NotDefAccessNotExportedFromUnnamed(sym,
4710 sym.modle));
4711 }
4712 }
4713 }
4714 }
4715
4716 /**
4717 * InvalidSymbolError error class indicating that an instance member
4718 * has erroneously been accessed from a static context.
4719 */
4720 class StaticError extends InvalidSymbolError {
4721
4722 StaticError(Symbol sym) {
4723 this(sym, "static error");
4724 }
4725
4726 StaticError(Symbol sym, String debugName) {
4727 super(STATICERR, sym, debugName);
4728 }
4729
4730 @Override
4731 JCDiagnostic getDiagnostic(JCDiagnostic.DiagnosticType dkind,
4732 DiagnosticPosition pos,
4733 Symbol location,
4734 Type site,
4735 Name name,
4736 List<Type> argtypes,
4737 List<Type> typeargtypes) {
4738 Symbol errSym = ((sym.kind == TYP && sym.type.hasTag(CLASS))
4739 ? types.erasure(sym.type).tsym
4740 : sym);
4741 return diags.create(dkind, log.currentSource(), pos,
4742 "non-static.cant.be.ref", kindName(sym), errSym);
4743 }
4744 }
4745
4746 /**
4747 * Specialization of {@link StaticError} for illegal
4748 * creation of local class instances from a static context.
4749 */
4750 class BadLocalClassCreation extends StaticError {
4751 BadLocalClassCreation(Symbol sym) {
4752 super(sym, "bad local class creation");
4753 }
4754
4755 @Override
4756 JCDiagnostic getDiagnostic(JCDiagnostic.DiagnosticType dkind,
4757 DiagnosticPosition pos,
4758 Symbol location,
4759 Type site,
4760 Name name,
4761 List<Type> argtypes,
4762 List<Type> typeargtypes) {
4763 return diags.create(dkind, log.currentSource(), pos,
4764 "local.cant.be.inst.static", kindName(sym), sym);
4765 }
4766 }
4767
4768 /**
4769 * Specialization of {@link InvalidSymbolError} for illegal
4770 * early accesses within a constructor prologue.
4771 */
4772 class RefBeforeCtorCalledError extends StaticError {
4773
4774 RefBeforeCtorCalledError(Symbol sym) {
4775 super(sym, "prologue error");
4776 }
4777
4778 @Override
4779 JCDiagnostic getDiagnostic(JCDiagnostic.DiagnosticType dkind,
4780 DiagnosticPosition pos,
4781 Symbol location,
4782 Type site,
4783 Name name,
4784 List<Type> argtypes,
4785 List<Type> typeargtypes) {
4786 Symbol errSym = ((sym.kind == TYP && sym.type.hasTag(CLASS))
4787 ? types.erasure(sym.type).tsym
4788 : sym);
4789 return diags.create(dkind, log.currentSource(), pos,
4790 "cant.ref.before.ctor.called", errSym);
4791 }
4792 }
4793
4794 /**
4795 * InvalidSymbolError error class indicating that a pair of symbols
4796 * (either methods, constructors or operands) are ambiguous
4797 * given an actual arguments/type argument list.
4798 */
4799 class AmbiguityError extends ResolveError {
4800
4801 /** The other maximally specific symbol */
4802 List<Symbol> ambiguousSyms = List.nil();
4803
4804 @Override
4805 public boolean exists() {
4806 return true;
4807 }
4808
4809 AmbiguityError(Symbol sym1, Symbol sym2) {
4810 super(AMBIGUOUS, "ambiguity error");
4811 ambiguousSyms = flatten(sym2).appendList(flatten(sym1));
4812 }
4813
4814 private List<Symbol> flatten(Symbol sym) {
4815 if (sym.kind == AMBIGUOUS) {
4816 return ((AmbiguityError)sym.baseSymbol()).ambiguousSyms;
4817 } else {
4818 return List.of(sym);
4819 }
4820 }
4821
4822 AmbiguityError addAmbiguousSymbol(Symbol s) {
4823 ambiguousSyms = ambiguousSyms.prepend(s);
4824 return this;
4825 }
4826
4827 @Override
4828 JCDiagnostic getDiagnostic(JCDiagnostic.DiagnosticType dkind,
4829 DiagnosticPosition pos,
4830 Symbol location,
4831 Type site,
4832 Name name,
4833 List<Type> argtypes,
4834 List<Type> typeargtypes) {
4835 List<Symbol> diagSyms = ambiguousSyms.reverse();
4836 Symbol s1 = diagSyms.head;
4837 Symbol s2 = diagSyms.tail.head;
4838 Name sname = s1.name;
4839 if (sname == names.init) sname = s1.owner.name;
4840 return diags.create(dkind, log.currentSource(),
4841 pos, "ref.ambiguous", sname,
4842 kindName(s1),
4843 s1,
4844 s1.location(site, types),
4845 kindName(s2),
4846 s2,
4847 s2.location(site, types));
4848 }
4849
4850 /**
4851 * If multiple applicable methods are found during overload and none of them
4852 * is more specific than the others, attempt to merge their signatures.
4853 */
4854 Symbol mergeAbstracts(Type site) {
4855 List<Symbol> ambiguousInOrder = ambiguousSyms.reverse();
4856 return types.mergeAbstracts(ambiguousInOrder, site, true).orElse(this);
4857 }
4858
4859 @Override
4860 protected Symbol access(Name name, TypeSymbol location) {
4861 Symbol firstAmbiguity = ambiguousSyms.last();
4862 return firstAmbiguity.kind == TYP ?
4863 types.createErrorType(name, location, firstAmbiguity.type).tsym :
4864 firstAmbiguity;
4865 }
4866 }
4867
4868 class BadVarargsMethod extends ResolveError {
4869
4870 ResolveError delegatedError;
4871
4872 BadVarargsMethod(ResolveError delegatedError) {
4873 super(delegatedError.kind, "badVarargs");
4874 this.delegatedError = delegatedError;
4875 }
4876
4877 @Override
4878 public Symbol baseSymbol() {
4879 return delegatedError.baseSymbol();
4880 }
4881
4882 @Override
4883 protected Symbol access(Name name, TypeSymbol location) {
4884 return delegatedError.access(name, location);
4885 }
4886
4887 @Override
4888 public boolean exists() {
4889 return true;
4890 }
4891
4892 @Override
4893 JCDiagnostic getDiagnostic(DiagnosticType dkind, DiagnosticPosition pos, Symbol location, Type site, Name name, List<Type> argtypes, List<Type> typeargtypes) {
4894 return delegatedError.getDiagnostic(dkind, pos, location, site, name, argtypes, typeargtypes);
4895 }
4896 }
4897
4898 /**
4899 * BadMethodReferenceError error class indicating that a method reference symbol has been found,
4900 * but with the wrong staticness.
4901 */
4902 class BadMethodReferenceError extends StaticError {
4903
4904 boolean unboundLookup;
4905
4906 public BadMethodReferenceError(Symbol sym, boolean unboundLookup) {
4907 super(sym, "bad method ref error");
4908 this.unboundLookup = unboundLookup;
4909 }
4910
4911 @Override
4912 JCDiagnostic getDiagnostic(DiagnosticType dkind, DiagnosticPosition pos, Symbol location, Type site, Name name, List<Type> argtypes, List<Type> typeargtypes) {
4913 final String key;
4914 if (!unboundLookup) {
4915 key = "bad.static.method.in.bound.lookup";
4916 } else if (sym.isStatic()) {
4917 key = "bad.static.method.in.unbound.lookup";
4918 } else {
4919 key = "bad.instance.method.in.unbound.lookup";
4920 }
4921 return sym.kind.isResolutionError() ?
4922 ((ResolveError)sym).getDiagnostic(dkind, pos, location, site, name, argtypes, typeargtypes) :
4923 diags.create(dkind, log.currentSource(), pos, key, Kinds.kindName(sym), sym);
4924 }
4925 }
4926
4927 class BadClassFileError extends InvalidSymbolError {
4928
4929 private final CompletionFailure ex;
4930
4931 public BadClassFileError(CompletionFailure ex) {
4932 super(HIDDEN, ex.sym, "BadClassFileError");
4933 this.name = sym.name;
4934 this.ex = ex;
4935 }
4936
4937 @Override
4938 JCDiagnostic getDiagnostic(DiagnosticType dkind, DiagnosticPosition pos, Symbol location, Type site, Name name, List<Type> argtypes, List<Type> typeargtypes) {
4939 JCDiagnostic d = diags.create(dkind, log.currentSource(), pos,
4940 "cant.access", ex.sym, ex.getDetailValue());
4941
4942 d.setFlag(DiagnosticFlag.NON_DEFERRABLE);
4943 return d;
4944 }
4945
4946 }
4947
4948 /**
4949 * Helper class for method resolution diagnostic simplification.
4950 * Certain resolution diagnostic are rewritten as simpler diagnostic
4951 * where the enclosing resolution diagnostic (i.e. 'inapplicable method')
4952 * is stripped away, as it doesn't carry additional info. The logic
4953 * for matching a given diagnostic is given in terms of a template
4954 * hierarchy: a diagnostic template can be specified programmatically,
4955 * so that only certain diagnostics are matched. Each templete is then
4956 * associated with a rewriter object that carries out the task of rewtiting
4957 * the diagnostic to a simpler one.
4958 */
4959 static class MethodResolutionDiagHelper {
4960
4961 /**
4962 * A diagnostic rewriter transforms a method resolution diagnostic
4963 * into a simpler one
4964 */
4965 interface DiagnosticRewriter {
4966 JCDiagnostic rewriteDiagnostic(JCDiagnostic.Factory diags,
4967 DiagnosticPosition preferredPos, DiagnosticSource preferredSource,
4968 DiagnosticType preferredKind, JCDiagnostic d);
4969 }
4970
4971 /**
4972 * A diagnostic template is made up of two ingredients: (i) a regular
4973 * expression for matching a diagnostic key and (ii) a list of sub-templates
4974 * for matching diagnostic arguments.
4975 */
4976 static class Template {
4977
4978 /** regex used to match diag key */
4979 String regex;
4980
4981 /** templates used to match diagnostic args */
4982 Template[] subTemplates;
4983
4984 Template(String key, Template... subTemplates) {
4985 this.regex = key;
4986 this.subTemplates = subTemplates;
4987 }
4988
4989 /**
4990 * Returns true if the regex matches the diagnostic key and if
4991 * all diagnostic arguments are matches by corresponding sub-templates.
4992 */
4993 boolean matches(Object o) {
4994 JCDiagnostic d = (JCDiagnostic)o;
4995 Object[] args = d.getArgs();
4996 if (!d.getCode().matches(regex) ||
4997 subTemplates.length != d.getArgs().length) {
4998 return false;
4999 }
5000 for (int i = 0; i < args.length ; i++) {
5001 if (!subTemplates[i].matches(args[i])) {
5002 return false;
5003 }
5004 }
5005 return true;
5006 }
5007 }
5008
5009 /**
5010 * Common rewriter for all argument mismatch simplifications.
5011 */
5012 static class ArgMismatchRewriter implements DiagnosticRewriter {
5013
5014 /** the index of the subdiagnostic to be used as primary. */
5015 int causeIndex;
5016
5017 public ArgMismatchRewriter(int causeIndex) {
5018 this.causeIndex = causeIndex;
5019 }
5020
5021 @Override
5022 public JCDiagnostic rewriteDiagnostic(JCDiagnostic.Factory diags,
5023 DiagnosticPosition preferredPos, DiagnosticSource preferredSource,
5024 DiagnosticType preferredKind, JCDiagnostic d) {
5025 JCDiagnostic cause = (JCDiagnostic)d.getArgs()[causeIndex];
5026 DiagnosticPosition pos = d.getDiagnosticPosition();
5027 if (pos == null) {
5028 pos = preferredPos;
5029 }
5030 return diags.create(preferredKind, preferredSource, pos,
5031 "prob.found.req", cause);
5032 }
5033 }
5034
5035 /** a dummy template that match any diagnostic argument */
5036 static final Template skip = new Template("") {
5037 @Override
5038 boolean matches(Object d) {
5039 return true;
5040 }
5041 };
5042
5043 /** template for matching inference-free arguments mismatch failures */
5044 static final Template argMismatchTemplate = new Template(MethodCheckDiag.ARG_MISMATCH.regex(), skip);
5045
5046 /** template for matching inference related arguments mismatch failures */
5047 static final Template inferArgMismatchTemplate = new Template(MethodCheckDiag.ARG_MISMATCH.regex(), skip, skip) {
5048 @Override
5049 boolean matches(Object o) {
5050 if (!super.matches(o)) {
5051 return false;
5052 }
5053 JCDiagnostic d = (JCDiagnostic)o;
5054 @SuppressWarnings("unchecked")
5055 List<Type> tvars = (List<Type>)d.getArgs()[0];
5056 return !containsAny(d, tvars);
5057 }
5058
5059 BiPredicate<Object, List<Type>> containsPredicate = (o, ts) -> {
5060 if (o instanceof Type type) {
5061 return type.containsAny(ts);
5062 } else if (o instanceof JCDiagnostic diagnostic) {
5063 return containsAny(diagnostic, ts);
5064 } else {
5065 return false;
5066 }
5067 };
5068
5069 boolean containsAny(JCDiagnostic d, List<Type> ts) {
5070 return Stream.of(d.getArgs())
5071 .anyMatch(o -> containsPredicate.test(o, ts));
5072 }
5073 };
5074
5075 /** rewriter map used for method resolution simplification */
5076 static final Map<Template, DiagnosticRewriter> rewriters = new LinkedHashMap<>();
5077
5078 static {
5079 rewriters.put(argMismatchTemplate, new ArgMismatchRewriter(0));
5080 rewriters.put(inferArgMismatchTemplate, new ArgMismatchRewriter(1));
5081 }
5082
5083 /**
5084 * Main entry point for diagnostic rewriting - given a diagnostic, see if any templates matches it,
5085 * and rewrite it accordingly.
5086 */
5087 static JCDiagnostic rewrite(JCDiagnostic.Factory diags, DiagnosticPosition pos, DiagnosticSource source,
5088 DiagnosticType dkind, JCDiagnostic d) {
5089 for (Map.Entry<Template, DiagnosticRewriter> _entry : rewriters.entrySet()) {
5090 if (_entry.getKey().matches(d)) {
5091 JCDiagnostic simpleDiag =
5092 _entry.getValue().rewriteDiagnostic(diags, pos, source, dkind, d);
5093 simpleDiag.setFlag(DiagnosticFlag.COMPRESSED);
5094 return simpleDiag;
5095 }
5096 }
5097 return null;
5098 }
5099 }
5100
5101 enum MethodResolutionPhase {
5102 BASIC(false, false),
5103 BOX(true, false),
5104 VARARITY(true, true) {
5105 @Override
5106 public Symbol mergeResults(Symbol bestSoFar, Symbol sym) {
5107 //Check invariants (see {@code LookupHelper.shouldStop})
5108 Assert.check(bestSoFar.kind.isResolutionError() && bestSoFar.kind != AMBIGUOUS);
5109 if (!sym.kind.isResolutionError()) {
5110 //varargs resolution successful
5111 return sym;
5112 } else {
5113 //pick best error
5114 switch (bestSoFar.kind) {
5115 case WRONG_MTH:
5116 case WRONG_MTHS:
5117 //Override previous errors if they were caused by argument mismatch.
5118 //This generally means preferring current symbols - but we need to pay
5119 //attention to the fact that the varargs lookup returns 'less' candidates
5120 //than the previous rounds, and adjust that accordingly.
5121 switch (sym.kind) {
5122 case WRONG_MTH:
5123 //if the previous round matched more than one method, return that
5124 //result instead
5125 return bestSoFar.kind == WRONG_MTHS ?
5126 bestSoFar : sym;
5127 case ABSENT_MTH:
5128 //do not override erroneous symbol if the arity lookup did not
5129 //match any method
5130 return bestSoFar;
5131 case WRONG_MTHS:
5132 default:
5133 //safe to override
5134 return sym;
5135 }
5136 default:
5137 //otherwise, return first error
5138 return bestSoFar;
5139 }
5140 }
5141 }
5142 };
5143
5144 final boolean isBoxingRequired;
5145 final boolean isVarargsRequired;
5146
5147 MethodResolutionPhase(boolean isBoxingRequired, boolean isVarargsRequired) {
5148 this.isBoxingRequired = isBoxingRequired;
5149 this.isVarargsRequired = isVarargsRequired;
5150 }
5151
5152 public boolean isBoxingRequired() {
5153 return isBoxingRequired;
5154 }
5155
5156 public boolean isVarargsRequired() {
5157 return isVarargsRequired;
5158 }
5159
5160 public Symbol mergeResults(Symbol prev, Symbol sym) {
5161 return sym;
5162 }
5163 }
5164
5165 final List<MethodResolutionPhase> methodResolutionSteps = List.of(BASIC, BOX, VARARITY);
5166
5167 /**
5168 * A resolution context is used to keep track of intermediate results of
5169 * overload resolution, such as list of method that are not applicable
5170 * (used to generate more precise diagnostics) and so on. Resolution contexts
5171 * can be nested - this means that when each overload resolution routine should
5172 * work within the resolution context it created.
5173 */
5174 class MethodResolutionContext {
5175
5176 private List<Candidate> candidates = List.nil();
5177
5178 MethodResolutionPhase step = null;
5179
5180 MethodCheck methodCheck = resolveMethodCheck;
5181
5182 private boolean internalResolution = false;
5183 private DeferredAttr.AttrMode attrMode = DeferredAttr.AttrMode.SPECULATIVE;
5184
5185 void addInapplicableCandidate(Symbol sym, JCDiagnostic details) {
5186 Candidate c = new Candidate(currentResolutionContext.step, sym, details, null);
5187 candidates = candidates.append(c);
5188 }
5189
5190 void addApplicableCandidate(Symbol sym, Type mtype) {
5191 Candidate c = new Candidate(currentResolutionContext.step, sym, null, mtype);
5192 candidates = candidates.append(c);
5193 }
5194
5195 DeferredAttrContext deferredAttrContext(Symbol sym, InferenceContext inferenceContext, ResultInfo pendingResult, Warner warn) {
5196 DeferredAttrContext parent = (pendingResult == null)
5197 ? deferredAttr.emptyDeferredAttrContext
5198 : pendingResult.checkContext.deferredAttrContext();
5199 return deferredAttr.new DeferredAttrContext(attrMode, sym, step,
5200 inferenceContext, parent, warn);
5201 }
5202
5203 /**
5204 * This class represents an overload resolution candidate. There are two
5205 * kinds of candidates: applicable methods and inapplicable methods;
5206 * applicable methods have a pointer to the instantiated method type,
5207 * while inapplicable candidates contain further details about the
5208 * reason why the method has been considered inapplicable.
5209 */
5210 class Candidate {
5211
5212 final MethodResolutionPhase step;
5213 final Symbol sym;
5214 final JCDiagnostic details;
5215 final Type mtype;
5216
5217 private Candidate(MethodResolutionPhase step, Symbol sym, JCDiagnostic details, Type mtype) {
5218 this.step = step;
5219 this.sym = sym;
5220 this.details = details;
5221 this.mtype = mtype;
5222 }
5223
5224 boolean isApplicable() {
5225 return mtype != null;
5226 }
5227 }
5228
5229 DeferredAttr.AttrMode attrMode() {
5230 return attrMode;
5231 }
5232 }
5233
5234 MethodResolutionContext currentResolutionContext = null;
5235 }