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src/share/classes/com/sun/tools/javac/comp/Resolve.java@c2234816495f
src/share/classes/com/sun/tools/javac/comp/Resolve.java
Tue, 06 Mar 2012 16:48:29 +0000
- author
- mcimadamore
- date
- Tue, 06 Mar 2012 16:48:29 +0000
- changeset 1221
- c2234816495f
- parent 1217
- d2508136751c
- child 1238
- e28a06a3c5d9
- permissions
- -rw-r--r--
7151070: NullPointerException in Resolve.isAccessible
Summary: Spurious accessibility check in TransTypes
Reviewed-by: jjg
1 /*
2 * Copyright (c) 1999, 2012, 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 */
26 package com.sun.tools.javac.comp;
28 import com.sun.tools.javac.api.Formattable.LocalizedString;
29 import com.sun.tools.javac.code.*;
30 import com.sun.tools.javac.code.Type.*;
31 import com.sun.tools.javac.code.Symbol.*;
32 import com.sun.tools.javac.comp.Resolve.MethodResolutionContext.Candidate;
33 import com.sun.tools.javac.jvm.*;
34 import com.sun.tools.javac.tree.*;
35 import com.sun.tools.javac.tree.JCTree.*;
36 import com.sun.tools.javac.util.*;
37 import com.sun.tools.javac.util.JCDiagnostic.DiagnosticFlag;
38 import com.sun.tools.javac.util.JCDiagnostic.DiagnosticPosition;
39 import com.sun.tools.javac.util.JCDiagnostic.DiagnosticType;
41 import java.util.Arrays;
42 import java.util.Collection;
43 import java.util.EnumMap;
44 import java.util.EnumSet;
45 import java.util.HashSet;
46 import java.util.Map;
47 import java.util.Set;
49 import javax.lang.model.element.ElementVisitor;
51 import static com.sun.tools.javac.code.Flags.*;
52 import static com.sun.tools.javac.code.Flags.BLOCK;
53 import static com.sun.tools.javac.code.Kinds.*;
54 import static com.sun.tools.javac.code.Kinds.ERRONEOUS;
55 import static com.sun.tools.javac.code.TypeTags.*;
56 import static com.sun.tools.javac.comp.Resolve.MethodResolutionPhase.*;
57 import static com.sun.tools.javac.tree.JCTree.Tag.*;
59 /** Helper class for name resolution, used mostly by the attribution phase.
60 *
61 * <p><b>This is NOT part of any supported API.
62 * If you write code that depends on this, you do so at your own risk.
63 * This code and its internal interfaces are subject to change or
64 * deletion without notice.</b>
65 */
66 public class Resolve {
67 protected static final Context.Key<Resolve> resolveKey =
68 new Context.Key<Resolve>();
70 Names names;
71 Log log;
72 Symtab syms;
73 Check chk;
74 Infer infer;
75 ClassReader reader;
76 TreeInfo treeinfo;
77 Types types;
78 JCDiagnostic.Factory diags;
79 public final boolean boxingEnabled; // = source.allowBoxing();
80 public final boolean varargsEnabled; // = source.allowVarargs();
81 public final boolean allowMethodHandles;
82 private final boolean debugResolve;
83 final EnumSet<VerboseResolutionMode> verboseResolutionMode;
85 Scope polymorphicSignatureScope;
87 protected Resolve(Context context) {
88 context.put(resolveKey, this);
89 syms = Symtab.instance(context);
91 varNotFound = new
92 SymbolNotFoundError(ABSENT_VAR);
93 wrongMethod = new
94 InapplicableSymbolError();
95 wrongMethods = new
96 InapplicableSymbolsError();
97 methodNotFound = new
98 SymbolNotFoundError(ABSENT_MTH);
99 typeNotFound = new
100 SymbolNotFoundError(ABSENT_TYP);
102 names = Names.instance(context);
103 log = Log.instance(context);
104 chk = Check.instance(context);
105 infer = Infer.instance(context);
106 reader = ClassReader.instance(context);
107 treeinfo = TreeInfo.instance(context);
108 types = Types.instance(context);
109 diags = JCDiagnostic.Factory.instance(context);
110 Source source = Source.instance(context);
111 boxingEnabled = source.allowBoxing();
112 varargsEnabled = source.allowVarargs();
113 Options options = Options.instance(context);
114 debugResolve = options.isSet("debugresolve");
115 verboseResolutionMode = VerboseResolutionMode.getVerboseResolutionMode(options);
116 Target target = Target.instance(context);
117 allowMethodHandles = target.hasMethodHandles();
118 polymorphicSignatureScope = new Scope(syms.noSymbol);
120 inapplicableMethodException = new InapplicableMethodException(diags);
121 }
123 /** error symbols, which are returned when resolution fails
124 */
125 private final SymbolNotFoundError varNotFound;
126 private final InapplicableSymbolError wrongMethod;
127 private final InapplicableSymbolsError wrongMethods;
128 private final SymbolNotFoundError methodNotFound;
129 private final SymbolNotFoundError typeNotFound;
131 public static Resolve instance(Context context) {
132 Resolve instance = context.get(resolveKey);
133 if (instance == null)
134 instance = new Resolve(context);
135 return instance;
136 }
138 // <editor-fold defaultstate="collapsed" desc="Verbose resolution diagnostics support">
139 enum VerboseResolutionMode {
140 SUCCESS("success"),
141 FAILURE("failure"),
142 APPLICABLE("applicable"),
143 INAPPLICABLE("inapplicable"),
144 DEFERRED_INST("deferred-inference"),
145 PREDEF("predef"),
146 OBJECT_INIT("object-init"),
147 INTERNAL("internal");
149 String opt;
151 private VerboseResolutionMode(String opt) {
152 this.opt = opt;
153 }
155 static EnumSet<VerboseResolutionMode> getVerboseResolutionMode(Options opts) {
156 String s = opts.get("verboseResolution");
157 EnumSet<VerboseResolutionMode> res = EnumSet.noneOf(VerboseResolutionMode.class);
158 if (s == null) return res;
159 if (s.contains("all")) {
160 res = EnumSet.allOf(VerboseResolutionMode.class);
161 }
162 Collection<String> args = Arrays.asList(s.split(","));
163 for (VerboseResolutionMode mode : values()) {
164 if (args.contains(mode.opt)) {
165 res.add(mode);
166 } else if (args.contains("-" + mode.opt)) {
167 res.remove(mode);
168 }
169 }
170 return res;
171 }
172 }
174 void reportVerboseResolutionDiagnostic(DiagnosticPosition dpos, Name name, Type site,
175 List<Type> argtypes, List<Type> typeargtypes, Symbol bestSoFar) {
176 boolean success = bestSoFar.kind < ERRONEOUS;
178 if (success && !verboseResolutionMode.contains(VerboseResolutionMode.SUCCESS)) {
179 return;
180 } else if (!success && !verboseResolutionMode.contains(VerboseResolutionMode.FAILURE)) {
181 return;
182 }
184 if (bestSoFar.name == names.init &&
185 bestSoFar.owner == syms.objectType.tsym &&
186 !verboseResolutionMode.contains(VerboseResolutionMode.OBJECT_INIT)) {
187 return; //skip diags for Object constructor resolution
188 } else if (site == syms.predefClass.type &&
189 !verboseResolutionMode.contains(VerboseResolutionMode.PREDEF)) {
190 return; //skip spurious diags for predef symbols (i.e. operators)
191 } else if (currentResolutionContext.internalResolution &&
192 !verboseResolutionMode.contains(VerboseResolutionMode.INTERNAL)) {
193 return;
194 }
196 int pos = 0;
197 int mostSpecificPos = -1;
198 ListBuffer<JCDiagnostic> subDiags = ListBuffer.lb();
199 for (Candidate c : currentResolutionContext.candidates) {
200 if (currentResolutionContext.step != c.step ||
201 (c.isApplicable() && !verboseResolutionMode.contains(VerboseResolutionMode.APPLICABLE)) ||
202 (!c.isApplicable() && !verboseResolutionMode.contains(VerboseResolutionMode.INAPPLICABLE))) {
203 continue;
204 } else {
205 subDiags.append(c.isApplicable() ?
206 getVerboseApplicableCandidateDiag(pos, c.sym, c.mtype) :
207 getVerboseInapplicableCandidateDiag(pos, c.sym, c.details));
208 if (c.sym == bestSoFar)
209 mostSpecificPos = pos;
210 pos++;
211 }
212 }
213 String key = success ? "verbose.resolve.multi" : "verbose.resolve.multi.1";
214 JCDiagnostic main = diags.note(log.currentSource(), dpos, key, name,
215 site.tsym, mostSpecificPos, currentResolutionContext.step,
216 methodArguments(argtypes), methodArguments(typeargtypes));
217 JCDiagnostic d = new JCDiagnostic.MultilineDiagnostic(main, subDiags.toList());
218 log.report(d);
219 }
221 JCDiagnostic getVerboseApplicableCandidateDiag(int pos, Symbol sym, Type inst) {
222 JCDiagnostic subDiag = null;
223 if (inst.getReturnType().tag == FORALL) {
224 Type diagType = types.createMethodTypeWithReturn(inst.asMethodType(),
225 ((ForAll)inst.getReturnType()).qtype);
226 subDiag = diags.fragment("partial.inst.sig", diagType);
227 } else if (sym.type.tag == FORALL) {
228 subDiag = diags.fragment("full.inst.sig", inst.asMethodType());
229 }
231 String key = subDiag == null ?
232 "applicable.method.found" :
233 "applicable.method.found.1";
235 return diags.fragment(key, pos, sym, subDiag);
236 }
238 JCDiagnostic getVerboseInapplicableCandidateDiag(int pos, Symbol sym, JCDiagnostic subDiag) {
239 return diags.fragment("not.applicable.method.found", pos, sym, subDiag);
240 }
241 // </editor-fold>
243 /* ************************************************************************
244 * Identifier resolution
245 *************************************************************************/
247 /** An environment is "static" if its static level is greater than
248 * the one of its outer environment
249 */
250 static boolean isStatic(Env<AttrContext> env) {
251 return env.info.staticLevel > env.outer.info.staticLevel;
252 }
254 /** An environment is an "initializer" if it is a constructor or
255 * an instance initializer.
256 */
257 static boolean isInitializer(Env<AttrContext> env) {
258 Symbol owner = env.info.scope.owner;
259 return owner.isConstructor() ||
260 owner.owner.kind == TYP &&
261 (owner.kind == VAR ||
262 owner.kind == MTH && (owner.flags() & BLOCK) != 0) &&
263 (owner.flags() & STATIC) == 0;
264 }
266 /** Is class accessible in given evironment?
267 * @param env The current environment.
268 * @param c The class whose accessibility is checked.
269 */
270 public boolean isAccessible(Env<AttrContext> env, TypeSymbol c) {
271 return isAccessible(env, c, false);
272 }
274 public boolean isAccessible(Env<AttrContext> env, TypeSymbol c, boolean checkInner) {
275 boolean isAccessible = false;
276 switch ((short)(c.flags() & AccessFlags)) {
277 case PRIVATE:
278 isAccessible =
279 env.enclClass.sym.outermostClass() ==
280 c.owner.outermostClass();
281 break;
282 case 0:
283 isAccessible =
284 env.toplevel.packge == c.owner // fast special case
285 ||
286 env.toplevel.packge == c.packge()
287 ||
288 // Hack: this case is added since synthesized default constructors
289 // of anonymous classes should be allowed to access
290 // classes which would be inaccessible otherwise.
291 env.enclMethod != null &&
292 (env.enclMethod.mods.flags & ANONCONSTR) != 0;
293 break;
294 default: // error recovery
295 case PUBLIC:
296 isAccessible = true;
297 break;
298 case PROTECTED:
299 isAccessible =
300 env.toplevel.packge == c.owner // fast special case
301 ||
302 env.toplevel.packge == c.packge()
303 ||
304 isInnerSubClass(env.enclClass.sym, c.owner);
305 break;
306 }
307 return (checkInner == false || c.type.getEnclosingType() == Type.noType) ?
308 isAccessible :
309 isAccessible && isAccessible(env, c.type.getEnclosingType(), checkInner);
310 }
311 //where
312 /** Is given class a subclass of given base class, or an inner class
313 * of a subclass?
314 * Return null if no such class exists.
315 * @param c The class which is the subclass or is contained in it.
316 * @param base The base class
317 */
318 private boolean isInnerSubClass(ClassSymbol c, Symbol base) {
319 while (c != null && !c.isSubClass(base, types)) {
320 c = c.owner.enclClass();
321 }
322 return c != null;
323 }
325 boolean isAccessible(Env<AttrContext> env, Type t) {
326 return isAccessible(env, t, false);
327 }
329 boolean isAccessible(Env<AttrContext> env, Type t, boolean checkInner) {
330 return (t.tag == ARRAY)
331 ? isAccessible(env, types.elemtype(t))
332 : isAccessible(env, t.tsym, checkInner);
333 }
335 /** Is symbol accessible as a member of given type in given evironment?
336 * @param env The current environment.
337 * @param site The type of which the tested symbol is regarded
338 * as a member.
339 * @param sym The symbol.
340 */
341 public boolean isAccessible(Env<AttrContext> env, Type site, Symbol sym) {
342 return isAccessible(env, site, sym, false);
343 }
344 public boolean isAccessible(Env<AttrContext> env, Type site, Symbol sym, boolean checkInner) {
345 if (sym.name == names.init && sym.owner != site.tsym) return false;
346 switch ((short)(sym.flags() & AccessFlags)) {
347 case PRIVATE:
348 return
349 (env.enclClass.sym == sym.owner // fast special case
350 ||
351 env.enclClass.sym.outermostClass() ==
352 sym.owner.outermostClass())
353 &&
354 sym.isInheritedIn(site.tsym, types);
355 case 0:
356 return
357 (env.toplevel.packge == sym.owner.owner // fast special case
358 ||
359 env.toplevel.packge == sym.packge())
360 &&
361 isAccessible(env, site, checkInner)
362 &&
363 sym.isInheritedIn(site.tsym, types)
364 &&
365 notOverriddenIn(site, sym);
366 case PROTECTED:
367 return
368 (env.toplevel.packge == sym.owner.owner // fast special case
369 ||
370 env.toplevel.packge == sym.packge()
371 ||
372 isProtectedAccessible(sym, env.enclClass.sym, site)
373 ||
374 // OK to select instance method or field from 'super' or type name
375 // (but type names should be disallowed elsewhere!)
376 env.info.selectSuper && (sym.flags() & STATIC) == 0 && sym.kind != TYP)
377 &&
378 isAccessible(env, site, checkInner)
379 &&
380 notOverriddenIn(site, sym);
381 default: // this case includes erroneous combinations as well
382 return isAccessible(env, site, checkInner) && notOverriddenIn(site, sym);
383 }
384 }
385 //where
386 /* `sym' is accessible only if not overridden by
387 * another symbol which is a member of `site'
388 * (because, if it is overridden, `sym' is not strictly
389 * speaking a member of `site'). A polymorphic signature method
390 * cannot be overridden (e.g. MH.invokeExact(Object[])).
391 */
392 private boolean notOverriddenIn(Type site, Symbol sym) {
393 if (sym.kind != MTH || sym.isConstructor() || sym.isStatic())
394 return true;
395 else {
396 Symbol s2 = ((MethodSymbol)sym).implementation(site.tsym, types, true);
397 return (s2 == null || s2 == sym || sym.owner == s2.owner ||
398 s2.isPolymorphicSignatureGeneric() ||
399 !types.isSubSignature(types.memberType(site, s2), types.memberType(site, sym)));
400 }
401 }
402 //where
403 /** Is given protected symbol accessible if it is selected from given site
404 * and the selection takes place in given class?
405 * @param sym The symbol with protected access
406 * @param c The class where the access takes place
407 * @site The type of the qualifier
408 */
409 private
410 boolean isProtectedAccessible(Symbol sym, ClassSymbol c, Type site) {
411 while (c != null &&
412 !(c.isSubClass(sym.owner, types) &&
413 (c.flags() & INTERFACE) == 0 &&
414 // In JLS 2e 6.6.2.1, the subclass restriction applies
415 // only to instance fields and methods -- types are excluded
416 // regardless of whether they are declared 'static' or not.
417 ((sym.flags() & STATIC) != 0 || sym.kind == TYP || site.tsym.isSubClass(c, types))))
418 c = c.owner.enclClass();
419 return c != null;
420 }
422 /** Try to instantiate the type of a method so that it fits
423 * given type arguments and argument types. If succesful, return
424 * the method's instantiated type, else return null.
425 * The instantiation will take into account an additional leading
426 * formal parameter if the method is an instance method seen as a member
427 * of un underdetermined site In this case, we treat site as an additional
428 * parameter and the parameters of the class containing the method as
429 * additional type variables that get instantiated.
430 *
431 * @param env The current environment
432 * @param site The type of which the method is a member.
433 * @param m The method symbol.
434 * @param argtypes The invocation's given value arguments.
435 * @param typeargtypes The invocation's given type arguments.
436 * @param allowBoxing Allow boxing conversions of arguments.
437 * @param useVarargs Box trailing arguments into an array for varargs.
438 */
439 Type rawInstantiate(Env<AttrContext> env,
440 Type site,
441 Symbol m,
442 List<Type> argtypes,
443 List<Type> typeargtypes,
444 boolean allowBoxing,
445 boolean useVarargs,
446 Warner warn)
447 throws Infer.InferenceException {
448 boolean polymorphicSignature = m.isPolymorphicSignatureGeneric() && allowMethodHandles;
449 if (useVarargs && (m.flags() & VARARGS) == 0)
450 throw inapplicableMethodException.setMessage();
451 Type mt = types.memberType(site, m);
453 // tvars is the list of formal type variables for which type arguments
454 // need to inferred.
455 List<Type> tvars = null;
456 if (env.info.tvars != null) {
457 tvars = types.newInstances(env.info.tvars);
458 mt = types.subst(mt, env.info.tvars, tvars);
459 }
460 if (typeargtypes == null) typeargtypes = List.nil();
461 if (mt.tag != FORALL && typeargtypes.nonEmpty()) {
462 // This is not a polymorphic method, but typeargs are supplied
463 // which is fine, see JLS 15.12.2.1
464 } else if (mt.tag == FORALL && typeargtypes.nonEmpty()) {
465 ForAll pmt = (ForAll) mt;
466 if (typeargtypes.length() != pmt.tvars.length())
467 throw inapplicableMethodException.setMessage("arg.length.mismatch"); // not enough args
468 // Check type arguments are within bounds
469 List<Type> formals = pmt.tvars;
470 List<Type> actuals = typeargtypes;
471 while (formals.nonEmpty() && actuals.nonEmpty()) {
472 List<Type> bounds = types.subst(types.getBounds((TypeVar)formals.head),
473 pmt.tvars, typeargtypes);
474 for (; bounds.nonEmpty(); bounds = bounds.tail)
475 if (!types.isSubtypeUnchecked(actuals.head, bounds.head, warn))
476 throw inapplicableMethodException.setMessage("explicit.param.do.not.conform.to.bounds",actuals.head, bounds);
477 formals = formals.tail;
478 actuals = actuals.tail;
479 }
480 mt = types.subst(pmt.qtype, pmt.tvars, typeargtypes);
481 } else if (mt.tag == FORALL) {
482 ForAll pmt = (ForAll) mt;
483 List<Type> tvars1 = types.newInstances(pmt.tvars);
484 tvars = tvars.appendList(tvars1);
485 mt = types.subst(pmt.qtype, pmt.tvars, tvars1);
486 }
488 // find out whether we need to go the slow route via infer
489 boolean instNeeded = tvars.tail != null || /*inlined: tvars.nonEmpty()*/
490 polymorphicSignature;
491 for (List<Type> l = argtypes;
492 l.tail != null/*inlined: l.nonEmpty()*/ && !instNeeded;
493 l = l.tail) {
494 if (l.head.tag == FORALL) instNeeded = true;
495 }
497 if (instNeeded)
498 return polymorphicSignature ?
499 infer.instantiatePolymorphicSignatureInstance(env, site, m.name, (MethodSymbol)m, argtypes) :
500 infer.instantiateMethod(env,
501 tvars,
502 (MethodType)mt,
503 m,
504 argtypes,
505 allowBoxing,
506 useVarargs,
507 warn);
509 checkRawArgumentsAcceptable(env, argtypes, mt.getParameterTypes(),
510 allowBoxing, useVarargs, warn);
511 return mt;
512 }
514 /** Same but returns null instead throwing a NoInstanceException
515 */
516 Type instantiate(Env<AttrContext> env,
517 Type site,
518 Symbol m,
519 List<Type> argtypes,
520 List<Type> typeargtypes,
521 boolean allowBoxing,
522 boolean useVarargs,
523 Warner warn) {
524 try {
525 return rawInstantiate(env, site, m, argtypes, typeargtypes,
526 allowBoxing, useVarargs, warn);
527 } catch (InapplicableMethodException ex) {
528 return null;
529 }
530 }
532 /** Check if a parameter list accepts a list of args.
533 */
534 boolean argumentsAcceptable(Env<AttrContext> env,
535 List<Type> argtypes,
536 List<Type> formals,
537 boolean allowBoxing,
538 boolean useVarargs,
539 Warner warn) {
540 try {
541 checkRawArgumentsAcceptable(env, argtypes, formals, allowBoxing, useVarargs, warn);
542 return true;
543 } catch (InapplicableMethodException ex) {
544 return false;
545 }
546 }
547 /**
548 * A check handler is used by the main method applicability routine in order
549 * to handle specific method applicability failures. It is assumed that a class
550 * implementing this interface should throw exceptions that are a subtype of
551 * InapplicableMethodException (see below). Such exception will terminate the
552 * method applicability check and propagate important info outwards (for the
553 * purpose of generating better diagnostics).
554 */
555 interface MethodCheckHandler {
556 /* The number of actuals and formals differ */
557 InapplicableMethodException arityMismatch();
558 /* An actual argument type does not conform to the corresponding formal type */
559 InapplicableMethodException argumentMismatch(boolean varargs, Type found, Type expected);
560 /* The element type of a varargs is not accessible in the current context */
561 InapplicableMethodException inaccessibleVarargs(Symbol location, Type expected);
562 }
564 /**
565 * Basic method check handler used within Resolve - all methods end up
566 * throwing InapplicableMethodException; a diagnostic fragment that describes
567 * the cause as to why the method is not applicable is set on the exception
568 * before it is thrown.
569 */
570 MethodCheckHandler resolveHandler = new MethodCheckHandler() {
571 public InapplicableMethodException arityMismatch() {
572 return inapplicableMethodException.setMessage("arg.length.mismatch");
573 }
574 public InapplicableMethodException argumentMismatch(boolean varargs, Type found, Type expected) {
575 String key = varargs ?
576 "varargs.argument.mismatch" :
577 "no.conforming.assignment.exists";
578 return inapplicableMethodException.setMessage(key,
579 found, expected);
580 }
581 public InapplicableMethodException inaccessibleVarargs(Symbol location, Type expected) {
582 return inapplicableMethodException.setMessage("inaccessible.varargs.type",
583 expected, Kinds.kindName(location), location);
584 }
585 };
587 void checkRawArgumentsAcceptable(Env<AttrContext> env,
588 List<Type> argtypes,
589 List<Type> formals,
590 boolean allowBoxing,
591 boolean useVarargs,
592 Warner warn) {
593 checkRawArgumentsAcceptable(env, List.<Type>nil(), argtypes, formals,
594 allowBoxing, useVarargs, warn, resolveHandler);
595 }
597 /**
598 * Main method applicability routine. Given a list of actual types A,
599 * a list of formal types F, determines whether the types in A are
600 * compatible (by method invocation conversion) with the types in F.
601 *
602 * Since this routine is shared between overload resolution and method
603 * type-inference, it is crucial that actual types are converted to the
604 * corresponding 'undet' form (i.e. where inference variables are replaced
605 * with undetvars) so that constraints can be propagated and collected.
606 *
607 * Moreover, if one or more types in A is a poly type, this routine calls
608 * Infer.instantiateArg in order to complete the poly type (this might involve
609 * deferred attribution).
610 *
611 * A method check handler (see above) is used in order to report errors.
612 */
613 List<Type> checkRawArgumentsAcceptable(Env<AttrContext> env,
614 List<Type> undetvars,
615 List<Type> argtypes,
616 List<Type> formals,
617 boolean allowBoxing,
618 boolean useVarargs,
619 Warner warn,
620 MethodCheckHandler handler) {
621 Type varargsFormal = useVarargs ? formals.last() : null;
622 ListBuffer<Type> checkedArgs = ListBuffer.lb();
624 if (varargsFormal == null &&
625 argtypes.size() != formals.size()) {
626 throw handler.arityMismatch(); // not enough args
627 }
629 while (argtypes.nonEmpty() && formals.head != varargsFormal) {
630 Type undetFormal = infer.asUndetType(formals.head, undetvars);
631 Type capturedActual = types.capture(argtypes.head);
632 boolean works = allowBoxing ?
633 types.isConvertible(capturedActual, undetFormal, warn) :
634 types.isSubtypeUnchecked(capturedActual, undetFormal, warn);
635 if (!works) {
636 throw handler.argumentMismatch(false, argtypes.head, formals.head);
637 }
638 checkedArgs.append(capturedActual);
639 argtypes = argtypes.tail;
640 formals = formals.tail;
641 }
643 if (formals.head != varargsFormal) {
644 throw handler.arityMismatch(); // not enough args
645 }
647 if (useVarargs) {
648 //note: if applicability check is triggered by most specific test,
649 //the last argument of a varargs is _not_ an array type (see JLS 15.12.2.5)
650 Type elt = types.elemtype(varargsFormal);
651 Type eltUndet = infer.asUndetType(elt, undetvars);
652 while (argtypes.nonEmpty()) {
653 Type capturedActual = types.capture(argtypes.head);
654 if (!types.isConvertible(capturedActual, eltUndet, warn)) {
655 throw handler.argumentMismatch(true, argtypes.head, elt);
656 }
657 checkedArgs.append(capturedActual);
658 argtypes = argtypes.tail;
659 }
660 //check varargs element type accessibility
661 if (undetvars.isEmpty() && !isAccessible(env, elt)) {
662 Symbol location = env.enclClass.sym;
663 throw handler.inaccessibleVarargs(location, elt);
664 }
665 }
666 return checkedArgs.toList();
667 }
668 // where
669 public static class InapplicableMethodException extends RuntimeException {
670 private static final long serialVersionUID = 0;
672 JCDiagnostic diagnostic;
673 JCDiagnostic.Factory diags;
675 InapplicableMethodException(JCDiagnostic.Factory diags) {
676 this.diagnostic = null;
677 this.diags = diags;
678 }
679 InapplicableMethodException setMessage() {
680 this.diagnostic = null;
681 return this;
682 }
683 InapplicableMethodException setMessage(String key) {
684 this.diagnostic = key != null ? diags.fragment(key) : null;
685 return this;
686 }
687 InapplicableMethodException setMessage(String key, Object... args) {
688 this.diagnostic = key != null ? diags.fragment(key, args) : null;
689 return this;
690 }
691 InapplicableMethodException setMessage(JCDiagnostic diag) {
692 this.diagnostic = diag;
693 return this;
694 }
696 public JCDiagnostic getDiagnostic() {
697 return diagnostic;
698 }
699 }
700 private final InapplicableMethodException inapplicableMethodException;
702 /* ***************************************************************************
703 * Symbol lookup
704 * the following naming conventions for arguments are used
705 *
706 * env is the environment where the symbol was mentioned
707 * site is the type of which the symbol is a member
708 * name is the symbol's name
709 * if no arguments are given
710 * argtypes are the value arguments, if we search for a method
711 *
712 * If no symbol was found, a ResolveError detailing the problem is returned.
713 ****************************************************************************/
715 /** Find field. Synthetic fields are always skipped.
716 * @param env The current environment.
717 * @param site The original type from where the selection takes place.
718 * @param name The name of the field.
719 * @param c The class to search for the field. This is always
720 * a superclass or implemented interface of site's class.
721 */
722 Symbol findField(Env<AttrContext> env,
723 Type site,
724 Name name,
725 TypeSymbol c) {
726 while (c.type.tag == TYPEVAR)
727 c = c.type.getUpperBound().tsym;
728 Symbol bestSoFar = varNotFound;
729 Symbol sym;
730 Scope.Entry e = c.members().lookup(name);
731 while (e.scope != null) {
732 if (e.sym.kind == VAR && (e.sym.flags_field & SYNTHETIC) == 0) {
733 return isAccessible(env, site, e.sym)
734 ? e.sym : new AccessError(env, site, e.sym);
735 }
736 e = e.next();
737 }
738 Type st = types.supertype(c.type);
739 if (st != null && (st.tag == CLASS || st.tag == TYPEVAR)) {
740 sym = findField(env, site, name, st.tsym);
741 if (sym.kind < bestSoFar.kind) bestSoFar = sym;
742 }
743 for (List<Type> l = types.interfaces(c.type);
744 bestSoFar.kind != AMBIGUOUS && l.nonEmpty();
745 l = l.tail) {
746 sym = findField(env, site, name, l.head.tsym);
747 if (bestSoFar.kind < AMBIGUOUS && sym.kind < AMBIGUOUS &&
748 sym.owner != bestSoFar.owner)
749 bestSoFar = new AmbiguityError(bestSoFar, sym);
750 else if (sym.kind < bestSoFar.kind)
751 bestSoFar = sym;
752 }
753 return bestSoFar;
754 }
756 /** Resolve a field identifier, throw a fatal error if not found.
757 * @param pos The position to use for error reporting.
758 * @param env The environment current at the method invocation.
759 * @param site The type of the qualifying expression, in which
760 * identifier is searched.
761 * @param name The identifier's name.
762 */
763 public VarSymbol resolveInternalField(DiagnosticPosition pos, Env<AttrContext> env,
764 Type site, Name name) {
765 Symbol sym = findField(env, site, name, site.tsym);
766 if (sym.kind == VAR) return (VarSymbol)sym;
767 else throw new FatalError(
768 diags.fragment("fatal.err.cant.locate.field",
769 name));
770 }
772 /** Find unqualified variable or field with given name.
773 * Synthetic fields always skipped.
774 * @param env The current environment.
775 * @param name The name of the variable or field.
776 */
777 Symbol findVar(Env<AttrContext> env, Name name) {
778 Symbol bestSoFar = varNotFound;
779 Symbol sym;
780 Env<AttrContext> env1 = env;
781 boolean staticOnly = false;
782 while (env1.outer != null) {
783 if (isStatic(env1)) staticOnly = true;
784 Scope.Entry e = env1.info.scope.lookup(name);
785 while (e.scope != null &&
786 (e.sym.kind != VAR ||
787 (e.sym.flags_field & SYNTHETIC) != 0))
788 e = e.next();
789 sym = (e.scope != null)
790 ? e.sym
791 : findField(
792 env1, env1.enclClass.sym.type, name, env1.enclClass.sym);
793 if (sym.exists()) {
794 if (staticOnly &&
795 sym.kind == VAR &&
796 sym.owner.kind == TYP &&
797 (sym.flags() & STATIC) == 0)
798 return new StaticError(sym);
799 else
800 return sym;
801 } else if (sym.kind < bestSoFar.kind) {
802 bestSoFar = sym;
803 }
805 if ((env1.enclClass.sym.flags() & STATIC) != 0) staticOnly = true;
806 env1 = env1.outer;
807 }
809 sym = findField(env, syms.predefClass.type, name, syms.predefClass);
810 if (sym.exists())
811 return sym;
812 if (bestSoFar.exists())
813 return bestSoFar;
815 Scope.Entry e = env.toplevel.namedImportScope.lookup(name);
816 for (; e.scope != null; e = e.next()) {
817 sym = e.sym;
818 Type origin = e.getOrigin().owner.type;
819 if (sym.kind == VAR) {
820 if (e.sym.owner.type != origin)
821 sym = sym.clone(e.getOrigin().owner);
822 return isAccessible(env, origin, sym)
823 ? sym : new AccessError(env, origin, sym);
824 }
825 }
827 Symbol origin = null;
828 e = env.toplevel.starImportScope.lookup(name);
829 for (; e.scope != null; e = e.next()) {
830 sym = e.sym;
831 if (sym.kind != VAR)
832 continue;
833 // invariant: sym.kind == VAR
834 if (bestSoFar.kind < AMBIGUOUS && sym.owner != bestSoFar.owner)
835 return new AmbiguityError(bestSoFar, sym);
836 else if (bestSoFar.kind >= VAR) {
837 origin = e.getOrigin().owner;
838 bestSoFar = isAccessible(env, origin.type, sym)
839 ? sym : new AccessError(env, origin.type, sym);
840 }
841 }
842 if (bestSoFar.kind == VAR && bestSoFar.owner.type != origin.type)
843 return bestSoFar.clone(origin);
844 else
845 return bestSoFar;
846 }
848 Warner noteWarner = new Warner();
850 /** Select the best method for a call site among two choices.
851 * @param env The current environment.
852 * @param site The original type from where the
853 * selection takes place.
854 * @param argtypes The invocation's value arguments,
855 * @param typeargtypes The invocation's type arguments,
856 * @param sym Proposed new best match.
857 * @param bestSoFar Previously found best match.
858 * @param allowBoxing Allow boxing conversions of arguments.
859 * @param useVarargs Box trailing arguments into an array for varargs.
860 */
861 @SuppressWarnings("fallthrough")
862 Symbol selectBest(Env<AttrContext> env,
863 Type site,
864 List<Type> argtypes,
865 List<Type> typeargtypes,
866 Symbol sym,
867 Symbol bestSoFar,
868 boolean allowBoxing,
869 boolean useVarargs,
870 boolean operator) {
871 if (sym.kind == ERR) return bestSoFar;
872 if (!sym.isInheritedIn(site.tsym, types)) return bestSoFar;
873 Assert.check(sym.kind < AMBIGUOUS);
874 try {
875 Type mt = rawInstantiate(env, site, sym, argtypes, typeargtypes,
876 allowBoxing, useVarargs, Warner.noWarnings);
877 if (!operator)
878 currentResolutionContext.addApplicableCandidate(sym, mt);
879 } catch (InapplicableMethodException ex) {
880 if (!operator)
881 currentResolutionContext.addInapplicableCandidate(sym, ex.getDiagnostic());
882 switch (bestSoFar.kind) {
883 case ABSENT_MTH:
884 return wrongMethod;
885 case WRONG_MTH:
886 if (operator) return bestSoFar;
887 case WRONG_MTHS:
888 return wrongMethods;
889 default:
890 return bestSoFar;
891 }
892 }
893 if (!isAccessible(env, site, sym)) {
894 return (bestSoFar.kind == ABSENT_MTH)
895 ? new AccessError(env, site, sym)
896 : bestSoFar;
897 }
898 return (bestSoFar.kind > AMBIGUOUS)
899 ? sym
900 : mostSpecific(sym, bestSoFar, env, site,
901 allowBoxing && operator, useVarargs);
902 }
904 /* Return the most specific of the two methods for a call,
905 * given that both are accessible and applicable.
906 * @param m1 A new candidate for most specific.
907 * @param m2 The previous most specific candidate.
908 * @param env The current environment.
909 * @param site The original type from where the selection
910 * takes place.
911 * @param allowBoxing Allow boxing conversions of arguments.
912 * @param useVarargs Box trailing arguments into an array for varargs.
913 */
914 Symbol mostSpecific(Symbol m1,
915 Symbol m2,
916 Env<AttrContext> env,
917 final Type site,
918 boolean allowBoxing,
919 boolean useVarargs) {
920 switch (m2.kind) {
921 case MTH:
922 if (m1 == m2) return m1;
923 boolean m1SignatureMoreSpecific = signatureMoreSpecific(env, site, m1, m2, allowBoxing, useVarargs);
924 boolean m2SignatureMoreSpecific = signatureMoreSpecific(env, site, m2, m1, allowBoxing, useVarargs);
925 if (m1SignatureMoreSpecific && m2SignatureMoreSpecific) {
926 Type mt1 = types.memberType(site, m1);
927 Type mt2 = types.memberType(site, m2);
928 if (!types.overrideEquivalent(mt1, mt2))
929 return ambiguityError(m1, m2);
931 // same signature; select (a) the non-bridge method, or
932 // (b) the one that overrides the other, or (c) the concrete
933 // one, or (d) merge both abstract signatures
934 if ((m1.flags() & BRIDGE) != (m2.flags() & BRIDGE))
935 return ((m1.flags() & BRIDGE) != 0) ? m2 : m1;
937 // if one overrides or hides the other, use it
938 TypeSymbol m1Owner = (TypeSymbol)m1.owner;
939 TypeSymbol m2Owner = (TypeSymbol)m2.owner;
940 if (types.asSuper(m1Owner.type, m2Owner) != null &&
941 ((m1.owner.flags_field & INTERFACE) == 0 ||
942 (m2.owner.flags_field & INTERFACE) != 0) &&
943 m1.overrides(m2, m1Owner, types, false))
944 return m1;
945 if (types.asSuper(m2Owner.type, m1Owner) != null &&
946 ((m2.owner.flags_field & INTERFACE) == 0 ||
947 (m1.owner.flags_field & INTERFACE) != 0) &&
948 m2.overrides(m1, m2Owner, types, false))
949 return m2;
950 boolean m1Abstract = (m1.flags() & ABSTRACT) != 0;
951 boolean m2Abstract = (m2.flags() & ABSTRACT) != 0;
952 if (m1Abstract && !m2Abstract) return m2;
953 if (m2Abstract && !m1Abstract) return m1;
954 // both abstract or both concrete
955 if (!m1Abstract && !m2Abstract)
956 return ambiguityError(m1, m2);
957 // check that both signatures have the same erasure
958 if (!types.isSameTypes(m1.erasure(types).getParameterTypes(),
959 m2.erasure(types).getParameterTypes()))
960 return ambiguityError(m1, m2);
961 // both abstract, neither overridden; merge throws clause and result type
962 Type mst = mostSpecificReturnType(mt1, mt2);
963 if (mst == null) {
964 // Theoretically, this can't happen, but it is possible
965 // due to error recovery or mixing incompatible class files
966 return ambiguityError(m1, m2);
967 }
968 Symbol mostSpecific = mst == mt1 ? m1 : m2;
969 List<Type> allThrown = chk.intersect(mt1.getThrownTypes(), mt2.getThrownTypes());
970 Type newSig = types.createMethodTypeWithThrown(mostSpecific.type, allThrown);
971 MethodSymbol result = new MethodSymbol(
972 mostSpecific.flags(),
973 mostSpecific.name,
974 newSig,
975 mostSpecific.owner) {
976 @Override
977 public MethodSymbol implementation(TypeSymbol origin, Types types, boolean checkResult) {
978 if (origin == site.tsym)
979 return this;
980 else
981 return super.implementation(origin, types, checkResult);
982 }
983 };
984 return result;
985 }
986 if (m1SignatureMoreSpecific) return m1;
987 if (m2SignatureMoreSpecific) return m2;
988 return ambiguityError(m1, m2);
989 case AMBIGUOUS:
990 AmbiguityError e = (AmbiguityError)m2;
991 Symbol err1 = mostSpecific(m1, e.sym, env, site, allowBoxing, useVarargs);
992 Symbol err2 = mostSpecific(m1, e.sym2, env, site, allowBoxing, useVarargs);
993 if (err1 == err2) return err1;
994 if (err1 == e.sym && err2 == e.sym2) return m2;
995 if (err1 instanceof AmbiguityError &&
996 err2 instanceof AmbiguityError &&
997 ((AmbiguityError)err1).sym == ((AmbiguityError)err2).sym)
998 return ambiguityError(m1, m2);
999 else
1000 return ambiguityError(err1, err2);
1001 default:
1002 throw new AssertionError();
1003 }
1004 }
1005 //where
1006 private boolean signatureMoreSpecific(Env<AttrContext> env, Type site, Symbol m1, Symbol m2, boolean allowBoxing, boolean useVarargs) {
1007 noteWarner.clear();
1008 Type mtype1 = types.memberType(site, adjustVarargs(m1, m2, useVarargs));
1009 Type mtype2 = instantiate(env, site, adjustVarargs(m2, m1, useVarargs),
1010 types.lowerBoundArgtypes(mtype1), null,
1011 allowBoxing, false, noteWarner);
1012 return mtype2 != null &&
1013 !noteWarner.hasLint(Lint.LintCategory.UNCHECKED);
1014 }
1015 //where
1016 private Symbol adjustVarargs(Symbol to, Symbol from, boolean useVarargs) {
1017 List<Type> fromArgs = from.type.getParameterTypes();
1018 List<Type> toArgs = to.type.getParameterTypes();
1019 if (useVarargs &&
1020 (from.flags() & VARARGS) != 0 &&
1021 (to.flags() & VARARGS) != 0) {
1022 Type varargsTypeFrom = fromArgs.last();
1023 Type varargsTypeTo = toArgs.last();
1024 ListBuffer<Type> args = ListBuffer.lb();
1025 if (toArgs.length() < fromArgs.length()) {
1026 //if we are checking a varargs method 'from' against another varargs
1027 //method 'to' (where arity of 'to' < arity of 'from') then expand signature
1028 //of 'to' to 'fit' arity of 'from' (this means adding fake formals to 'to'
1029 //until 'to' signature has the same arity as 'from')
1030 while (fromArgs.head != varargsTypeFrom) {
1031 args.append(toArgs.head == varargsTypeTo ? types.elemtype(varargsTypeTo) : toArgs.head);
1032 fromArgs = fromArgs.tail;
1033 toArgs = toArgs.head == varargsTypeTo ?
1034 toArgs :
1035 toArgs.tail;
1036 }
1037 } else {
1038 //formal argument list is same as original list where last
1039 //argument (array type) is removed
1040 args.appendList(toArgs.reverse().tail.reverse());
1041 }
1042 //append varargs element type as last synthetic formal
1043 args.append(types.elemtype(varargsTypeTo));
1044 Type mtype = types.createMethodTypeWithParameters(to.type, args.toList());
1045 return new MethodSymbol(to.flags_field & ~VARARGS, to.name, mtype, to.owner);
1046 } else {
1047 return to;
1048 }
1049 }
1050 //where
1051 Type mostSpecificReturnType(Type mt1, Type mt2) {
1052 Type rt1 = mt1.getReturnType();
1053 Type rt2 = mt2.getReturnType();
1055 if (mt1.tag == FORALL && mt2.tag == FORALL) {
1056 //if both are generic methods, adjust return type ahead of subtyping check
1057 rt1 = types.subst(rt1, mt1.getTypeArguments(), mt2.getTypeArguments());
1058 }
1059 //first use subtyping, then return type substitutability
1060 if (types.isSubtype(rt1, rt2)) {
1061 return mt1;
1062 } else if (types.isSubtype(rt2, rt1)) {
1063 return mt2;
1064 } else if (types.returnTypeSubstitutable(mt1, mt2)) {
1065 return mt1;
1066 } else if (types.returnTypeSubstitutable(mt2, mt1)) {
1067 return mt2;
1068 } else {
1069 return null;
1070 }
1071 }
1072 //where
1073 Symbol ambiguityError(Symbol m1, Symbol m2) {
1074 if (((m1.flags() | m2.flags()) & CLASH) != 0) {
1075 return (m1.flags() & CLASH) == 0 ? m1 : m2;
1076 } else {
1077 return new AmbiguityError(m1, m2);
1078 }
1079 }
1081 /** Find best qualified method matching given name, type and value
1082 * arguments.
1083 * @param env The current environment.
1084 * @param site The original type from where the selection
1085 * takes place.
1086 * @param name The method's name.
1087 * @param argtypes The method's value arguments.
1088 * @param typeargtypes The method's type arguments
1089 * @param allowBoxing Allow boxing conversions of arguments.
1090 * @param useVarargs Box trailing arguments into an array for varargs.
1091 */
1092 Symbol findMethod(Env<AttrContext> env,
1093 Type site,
1094 Name name,
1095 List<Type> argtypes,
1096 List<Type> typeargtypes,
1097 boolean allowBoxing,
1098 boolean useVarargs,
1099 boolean operator) {
1100 Symbol bestSoFar = methodNotFound;
1101 bestSoFar = findMethod(env,
1102 site,
1103 name,
1104 argtypes,
1105 typeargtypes,
1106 site.tsym.type,
1107 true,
1108 bestSoFar,
1109 allowBoxing,
1110 useVarargs,
1111 operator,
1112 new HashSet<TypeSymbol>());
1113 reportVerboseResolutionDiagnostic(env.tree.pos(), name, site, argtypes, typeargtypes, bestSoFar);
1114 return bestSoFar;
1115 }
1116 // where
1117 private Symbol findMethod(Env<AttrContext> env,
1118 Type site,
1119 Name name,
1120 List<Type> argtypes,
1121 List<Type> typeargtypes,
1122 Type intype,
1123 boolean abstractok,
1124 Symbol bestSoFar,
1125 boolean allowBoxing,
1126 boolean useVarargs,
1127 boolean operator,
1128 Set<TypeSymbol> seen) {
1129 for (Type ct = intype; ct.tag == CLASS || ct.tag == TYPEVAR; ct = types.supertype(ct)) {
1130 while (ct.tag == TYPEVAR)
1131 ct = ct.getUpperBound();
1132 ClassSymbol c = (ClassSymbol)ct.tsym;
1133 if (!seen.add(c)) return bestSoFar;
1134 if ((c.flags() & (ABSTRACT | INTERFACE | ENUM)) == 0)
1135 abstractok = false;
1136 for (Scope.Entry e = c.members().lookup(name);
1137 e.scope != null;
1138 e = e.next()) {
1139 //- System.out.println(" e " + e.sym);
1140 if (e.sym.kind == MTH &&
1141 (e.sym.flags_field & SYNTHETIC) == 0) {
1142 bestSoFar = selectBest(env, site, argtypes, typeargtypes,
1143 e.sym, bestSoFar,
1144 allowBoxing,
1145 useVarargs,
1146 operator);
1147 }
1148 }
1149 if (name == names.init)
1150 break;
1151 //- System.out.println(" - " + bestSoFar);
1152 if (abstractok) {
1153 Symbol concrete = methodNotFound;
1154 if ((bestSoFar.flags() & ABSTRACT) == 0)
1155 concrete = bestSoFar;
1156 for (List<Type> l = types.interfaces(c.type);
1157 l.nonEmpty();
1158 l = l.tail) {
1159 bestSoFar = findMethod(env, site, name, argtypes,
1160 typeargtypes,
1161 l.head, abstractok, bestSoFar,
1162 allowBoxing, useVarargs, operator, seen);
1163 }
1164 if (concrete != bestSoFar &&
1165 concrete.kind < ERR && bestSoFar.kind < ERR &&
1166 types.isSubSignature(concrete.type, bestSoFar.type))
1167 bestSoFar = concrete;
1168 }
1169 }
1170 return bestSoFar;
1171 }
1173 /** Find unqualified method matching given name, type and value arguments.
1174 * @param env The current environment.
1175 * @param name The method's name.
1176 * @param argtypes The method's value arguments.
1177 * @param typeargtypes The method's type arguments.
1178 * @param allowBoxing Allow boxing conversions of arguments.
1179 * @param useVarargs Box trailing arguments into an array for varargs.
1180 */
1181 Symbol findFun(Env<AttrContext> env, Name name,
1182 List<Type> argtypes, List<Type> typeargtypes,
1183 boolean allowBoxing, boolean useVarargs) {
1184 Symbol bestSoFar = methodNotFound;
1185 Symbol sym;
1186 Env<AttrContext> env1 = env;
1187 boolean staticOnly = false;
1188 while (env1.outer != null) {
1189 if (isStatic(env1)) staticOnly = true;
1190 sym = findMethod(
1191 env1, env1.enclClass.sym.type, name, argtypes, typeargtypes,
1192 allowBoxing, useVarargs, false);
1193 if (sym.exists()) {
1194 if (staticOnly &&
1195 sym.kind == MTH &&
1196 sym.owner.kind == TYP &&
1197 (sym.flags() & STATIC) == 0) return new StaticError(sym);
1198 else return sym;
1199 } else if (sym.kind < bestSoFar.kind) {
1200 bestSoFar = sym;
1201 }
1202 if ((env1.enclClass.sym.flags() & STATIC) != 0) staticOnly = true;
1203 env1 = env1.outer;
1204 }
1206 sym = findMethod(env, syms.predefClass.type, name, argtypes,
1207 typeargtypes, allowBoxing, useVarargs, false);
1208 if (sym.exists())
1209 return sym;
1211 Scope.Entry e = env.toplevel.namedImportScope.lookup(name);
1212 for (; e.scope != null; e = e.next()) {
1213 sym = e.sym;
1214 Type origin = e.getOrigin().owner.type;
1215 if (sym.kind == MTH) {
1216 if (e.sym.owner.type != origin)
1217 sym = sym.clone(e.getOrigin().owner);
1218 if (!isAccessible(env, origin, sym))
1219 sym = new AccessError(env, origin, sym);
1220 bestSoFar = selectBest(env, origin,
1221 argtypes, typeargtypes,
1222 sym, bestSoFar,
1223 allowBoxing, useVarargs, false);
1224 }
1225 }
1226 if (bestSoFar.exists())
1227 return bestSoFar;
1229 e = env.toplevel.starImportScope.lookup(name);
1230 for (; e.scope != null; e = e.next()) {
1231 sym = e.sym;
1232 Type origin = e.getOrigin().owner.type;
1233 if (sym.kind == MTH) {
1234 if (e.sym.owner.type != origin)
1235 sym = sym.clone(e.getOrigin().owner);
1236 if (!isAccessible(env, origin, sym))
1237 sym = new AccessError(env, origin, sym);
1238 bestSoFar = selectBest(env, origin,
1239 argtypes, typeargtypes,
1240 sym, bestSoFar,
1241 allowBoxing, useVarargs, false);
1242 }
1243 }
1244 return bestSoFar;
1245 }
1247 /** Load toplevel or member class with given fully qualified name and
1248 * verify that it is accessible.
1249 * @param env The current environment.
1250 * @param name The fully qualified name of the class to be loaded.
1251 */
1252 Symbol loadClass(Env<AttrContext> env, Name name) {
1253 try {
1254 ClassSymbol c = reader.loadClass(name);
1255 return isAccessible(env, c) ? c : new AccessError(c);
1256 } catch (ClassReader.BadClassFile err) {
1257 throw err;
1258 } catch (CompletionFailure ex) {
1259 return typeNotFound;
1260 }
1261 }
1263 /** Find qualified member type.
1264 * @param env The current environment.
1265 * @param site The original type from where the selection takes
1266 * place.
1267 * @param name The type's name.
1268 * @param c The class to search for the member type. This is
1269 * always a superclass or implemented interface of
1270 * site's class.
1271 */
1272 Symbol findMemberType(Env<AttrContext> env,
1273 Type site,
1274 Name name,
1275 TypeSymbol c) {
1276 Symbol bestSoFar = typeNotFound;
1277 Symbol sym;
1278 Scope.Entry e = c.members().lookup(name);
1279 while (e.scope != null) {
1280 if (e.sym.kind == TYP) {
1281 return isAccessible(env, site, e.sym)
1282 ? e.sym
1283 : new AccessError(env, site, e.sym);
1284 }
1285 e = e.next();
1286 }
1287 Type st = types.supertype(c.type);
1288 if (st != null && st.tag == CLASS) {
1289 sym = findMemberType(env, site, name, st.tsym);
1290 if (sym.kind < bestSoFar.kind) bestSoFar = sym;
1291 }
1292 for (List<Type> l = types.interfaces(c.type);
1293 bestSoFar.kind != AMBIGUOUS && l.nonEmpty();
1294 l = l.tail) {
1295 sym = findMemberType(env, site, name, l.head.tsym);
1296 if (bestSoFar.kind < AMBIGUOUS && sym.kind < AMBIGUOUS &&
1297 sym.owner != bestSoFar.owner)
1298 bestSoFar = new AmbiguityError(bestSoFar, sym);
1299 else if (sym.kind < bestSoFar.kind)
1300 bestSoFar = sym;
1301 }
1302 return bestSoFar;
1303 }
1305 /** Find a global type in given scope and load corresponding class.
1306 * @param env The current environment.
1307 * @param scope The scope in which to look for the type.
1308 * @param name The type's name.
1309 */
1310 Symbol findGlobalType(Env<AttrContext> env, Scope scope, Name name) {
1311 Symbol bestSoFar = typeNotFound;
1312 for (Scope.Entry e = scope.lookup(name); e.scope != null; e = e.next()) {
1313 Symbol sym = loadClass(env, e.sym.flatName());
1314 if (bestSoFar.kind == TYP && sym.kind == TYP &&
1315 bestSoFar != sym)
1316 return new AmbiguityError(bestSoFar, sym);
1317 else if (sym.kind < bestSoFar.kind)
1318 bestSoFar = sym;
1319 }
1320 return bestSoFar;
1321 }
1323 /** Find an unqualified type symbol.
1324 * @param env The current environment.
1325 * @param name The type's name.
1326 */
1327 Symbol findType(Env<AttrContext> env, Name name) {
1328 Symbol bestSoFar = typeNotFound;
1329 Symbol sym;
1330 boolean staticOnly = false;
1331 for (Env<AttrContext> env1 = env; env1.outer != null; env1 = env1.outer) {
1332 if (isStatic(env1)) staticOnly = true;
1333 for (Scope.Entry e = env1.info.scope.lookup(name);
1334 e.scope != null;
1335 e = e.next()) {
1336 if (e.sym.kind == TYP) {
1337 if (staticOnly &&
1338 e.sym.type.tag == TYPEVAR &&
1339 e.sym.owner.kind == TYP) return new StaticError(e.sym);
1340 return e.sym;
1341 }
1342 }
1344 sym = findMemberType(env1, env1.enclClass.sym.type, name,
1345 env1.enclClass.sym);
1346 if (staticOnly && sym.kind == TYP &&
1347 sym.type.tag == CLASS &&
1348 sym.type.getEnclosingType().tag == CLASS &&
1349 env1.enclClass.sym.type.isParameterized() &&
1350 sym.type.getEnclosingType().isParameterized())
1351 return new StaticError(sym);
1352 else if (sym.exists()) return sym;
1353 else if (sym.kind < bestSoFar.kind) bestSoFar = sym;
1355 JCClassDecl encl = env1.baseClause ? (JCClassDecl)env1.tree : env1.enclClass;
1356 if ((encl.sym.flags() & STATIC) != 0)
1357 staticOnly = true;
1358 }
1360 if (!env.tree.hasTag(IMPORT)) {
1361 sym = findGlobalType(env, env.toplevel.namedImportScope, name);
1362 if (sym.exists()) return sym;
1363 else if (sym.kind < bestSoFar.kind) bestSoFar = sym;
1365 sym = findGlobalType(env, env.toplevel.packge.members(), name);
1366 if (sym.exists()) return sym;
1367 else if (sym.kind < bestSoFar.kind) bestSoFar = sym;
1369 sym = findGlobalType(env, env.toplevel.starImportScope, name);
1370 if (sym.exists()) return sym;
1371 else if (sym.kind < bestSoFar.kind) bestSoFar = sym;
1372 }
1374 return bestSoFar;
1375 }
1377 /** Find an unqualified identifier which matches a specified kind set.
1378 * @param env The current environment.
1379 * @param name The indentifier's name.
1380 * @param kind Indicates the possible symbol kinds
1381 * (a subset of VAL, TYP, PCK).
1382 */
1383 Symbol findIdent(Env<AttrContext> env, Name name, int kind) {
1384 Symbol bestSoFar = typeNotFound;
1385 Symbol sym;
1387 if ((kind & VAR) != 0) {
1388 sym = findVar(env, name);
1389 if (sym.exists()) return sym;
1390 else if (sym.kind < bestSoFar.kind) bestSoFar = sym;
1391 }
1393 if ((kind & TYP) != 0) {
1394 sym = findType(env, name);
1395 if (sym.exists()) return sym;
1396 else if (sym.kind < bestSoFar.kind) bestSoFar = sym;
1397 }
1399 if ((kind & PCK) != 0) return reader.enterPackage(name);
1400 else return bestSoFar;
1401 }
1403 /** Find an identifier in a package which matches a specified kind set.
1404 * @param env The current environment.
1405 * @param name The identifier's name.
1406 * @param kind Indicates the possible symbol kinds
1407 * (a nonempty subset of TYP, PCK).
1408 */
1409 Symbol findIdentInPackage(Env<AttrContext> env, TypeSymbol pck,
1410 Name name, int kind) {
1411 Name fullname = TypeSymbol.formFullName(name, pck);
1412 Symbol bestSoFar = typeNotFound;
1413 PackageSymbol pack = null;
1414 if ((kind & PCK) != 0) {
1415 pack = reader.enterPackage(fullname);
1416 if (pack.exists()) return pack;
1417 }
1418 if ((kind & TYP) != 0) {
1419 Symbol sym = loadClass(env, fullname);
1420 if (sym.exists()) {
1421 // don't allow programs to use flatnames
1422 if (name == sym.name) return sym;
1423 }
1424 else if (sym.kind < bestSoFar.kind) bestSoFar = sym;
1425 }
1426 return (pack != null) ? pack : bestSoFar;
1427 }
1429 /** Find an identifier among the members of a given type `site'.
1430 * @param env The current environment.
1431 * @param site The type containing the symbol to be found.
1432 * @param name The identifier's name.
1433 * @param kind Indicates the possible symbol kinds
1434 * (a subset of VAL, TYP).
1435 */
1436 Symbol findIdentInType(Env<AttrContext> env, Type site,
1437 Name name, int kind) {
1438 Symbol bestSoFar = typeNotFound;
1439 Symbol sym;
1440 if ((kind & VAR) != 0) {
1441 sym = findField(env, site, name, site.tsym);
1442 if (sym.exists()) return sym;
1443 else if (sym.kind < bestSoFar.kind) bestSoFar = sym;
1444 }
1446 if ((kind & TYP) != 0) {
1447 sym = findMemberType(env, site, name, site.tsym);
1448 if (sym.exists()) return sym;
1449 else if (sym.kind < bestSoFar.kind) bestSoFar = sym;
1450 }
1451 return bestSoFar;
1452 }
1454 /* ***************************************************************************
1455 * Access checking
1456 * The following methods convert ResolveErrors to ErrorSymbols, issuing
1457 * an error message in the process
1458 ****************************************************************************/
1460 /** If `sym' is a bad symbol: report error and return errSymbol
1461 * else pass through unchanged,
1462 * additional arguments duplicate what has been used in trying to find the
1463 * symbol (--> flyweight pattern). This improves performance since we
1464 * expect misses to happen frequently.
1465 *
1466 * @param sym The symbol that was found, or a ResolveError.
1467 * @param pos The position to use for error reporting.
1468 * @param site The original type from where the selection took place.
1469 * @param name The symbol's name.
1470 * @param argtypes The invocation's value arguments,
1471 * if we looked for a method.
1472 * @param typeargtypes The invocation's type arguments,
1473 * if we looked for a method.
1474 */
1475 Symbol access(Symbol sym,
1476 DiagnosticPosition pos,
1477 Symbol location,
1478 Type site,
1479 Name name,
1480 boolean qualified,
1481 List<Type> argtypes,
1482 List<Type> typeargtypes) {
1483 if (sym.kind >= AMBIGUOUS) {
1484 ResolveError errSym = (ResolveError)sym;
1485 if (!site.isErroneous() &&
1486 !Type.isErroneous(argtypes) &&
1487 (typeargtypes==null || !Type.isErroneous(typeargtypes)))
1488 logResolveError(errSym, pos, location, site, name, argtypes, typeargtypes);
1489 sym = errSym.access(name, qualified ? site.tsym : syms.noSymbol);
1490 }
1491 return sym;
1492 }
1494 /** Same as original access(), but without location.
1495 */
1496 Symbol access(Symbol sym,
1497 DiagnosticPosition pos,
1498 Type site,
1499 Name name,
1500 boolean qualified,
1501 List<Type> argtypes,
1502 List<Type> typeargtypes) {
1503 return access(sym, pos, site.tsym, site, name, qualified, argtypes, typeargtypes);
1504 }
1506 /** Same as original access(), but without type arguments and arguments.
1507 */
1508 Symbol access(Symbol sym,
1509 DiagnosticPosition pos,
1510 Symbol location,
1511 Type site,
1512 Name name,
1513 boolean qualified) {
1514 if (sym.kind >= AMBIGUOUS)
1515 return access(sym, pos, location, site, name, qualified, List.<Type>nil(), null);
1516 else
1517 return sym;
1518 }
1520 /** Same as original access(), but without location, type arguments and arguments.
1521 */
1522 Symbol access(Symbol sym,
1523 DiagnosticPosition pos,
1524 Type site,
1525 Name name,
1526 boolean qualified) {
1527 return access(sym, pos, site.tsym, site, name, qualified);
1528 }
1530 /** Check that sym is not an abstract method.
1531 */
1532 void checkNonAbstract(DiagnosticPosition pos, Symbol sym) {
1533 if ((sym.flags() & ABSTRACT) != 0)
1534 log.error(pos, "abstract.cant.be.accessed.directly",
1535 kindName(sym), sym, sym.location());
1536 }
1538 /* ***************************************************************************
1539 * Debugging
1540 ****************************************************************************/
1542 /** print all scopes starting with scope s and proceeding outwards.
1543 * used for debugging.
1544 */
1545 public void printscopes(Scope s) {
1546 while (s != null) {
1547 if (s.owner != null)
1548 System.err.print(s.owner + ": ");
1549 for (Scope.Entry e = s.elems; e != null; e = e.sibling) {
1550 if ((e.sym.flags() & ABSTRACT) != 0)
1551 System.err.print("abstract ");
1552 System.err.print(e.sym + " ");
1553 }
1554 System.err.println();
1555 s = s.next;
1556 }
1557 }
1559 void printscopes(Env<AttrContext> env) {
1560 while (env.outer != null) {
1561 System.err.println("------------------------------");
1562 printscopes(env.info.scope);
1563 env = env.outer;
1564 }
1565 }
1567 public void printscopes(Type t) {
1568 while (t.tag == CLASS) {
1569 printscopes(t.tsym.members());
1570 t = types.supertype(t);
1571 }
1572 }
1574 /* ***************************************************************************
1575 * Name resolution
1576 * Naming conventions are as for symbol lookup
1577 * Unlike the find... methods these methods will report access errors
1578 ****************************************************************************/
1580 /** Resolve an unqualified (non-method) identifier.
1581 * @param pos The position to use for error reporting.
1582 * @param env The environment current at the identifier use.
1583 * @param name The identifier's name.
1584 * @param kind The set of admissible symbol kinds for the identifier.
1585 */
1586 Symbol resolveIdent(DiagnosticPosition pos, Env<AttrContext> env,
1587 Name name, int kind) {
1588 return access(
1589 findIdent(env, name, kind),
1590 pos, env.enclClass.sym.type, name, false);
1591 }
1593 /** Resolve an unqualified method identifier.
1594 * @param pos The position to use for error reporting.
1595 * @param env The environment current at the method invocation.
1596 * @param name The identifier's name.
1597 * @param argtypes The types of the invocation's value arguments.
1598 * @param typeargtypes The types of the invocation's type arguments.
1599 */
1600 Symbol resolveMethod(DiagnosticPosition pos,
1601 Env<AttrContext> env,
1602 Name name,
1603 List<Type> argtypes,
1604 List<Type> typeargtypes) {
1605 MethodResolutionContext prevResolutionContext = currentResolutionContext;
1606 try {
1607 currentResolutionContext = new MethodResolutionContext();
1608 Symbol sym = methodNotFound;
1609 List<MethodResolutionPhase> steps = methodResolutionSteps;
1610 while (steps.nonEmpty() &&
1611 steps.head.isApplicable(boxingEnabled, varargsEnabled) &&
1612 sym.kind >= ERRONEOUS) {
1613 currentResolutionContext.step = steps.head;
1614 sym = findFun(env, name, argtypes, typeargtypes,
1615 steps.head.isBoxingRequired,
1616 env.info.varArgs = steps.head.isVarargsRequired);
1617 currentResolutionContext.resolutionCache.put(steps.head, sym);
1618 steps = steps.tail;
1619 }
1620 if (sym.kind >= AMBIGUOUS) {//if nothing is found return the 'first' error
1621 MethodResolutionPhase errPhase =
1622 currentResolutionContext.firstErroneousResolutionPhase();
1623 sym = access(currentResolutionContext.resolutionCache.get(errPhase),
1624 pos, env.enclClass.sym.type, name, false, argtypes, typeargtypes);
1625 env.info.varArgs = errPhase.isVarargsRequired;
1626 }
1627 return sym;
1628 }
1629 finally {
1630 currentResolutionContext = prevResolutionContext;
1631 }
1632 }
1634 /** Resolve a qualified method identifier
1635 * @param pos The position to use for error reporting.
1636 * @param env The environment current at the method invocation.
1637 * @param site The type of the qualifying expression, in which
1638 * identifier is searched.
1639 * @param name The identifier's name.
1640 * @param argtypes The types of the invocation's value arguments.
1641 * @param typeargtypes The types of the invocation's type arguments.
1642 */
1643 Symbol resolveQualifiedMethod(DiagnosticPosition pos, Env<AttrContext> env,
1644 Type site, Name name, List<Type> argtypes,
1645 List<Type> typeargtypes) {
1646 return resolveQualifiedMethod(pos, env, site.tsym, site, name, argtypes, typeargtypes);
1647 }
1648 Symbol resolveQualifiedMethod(DiagnosticPosition pos, Env<AttrContext> env,
1649 Symbol location, Type site, Name name, List<Type> argtypes,
1650 List<Type> typeargtypes) {
1651 return resolveQualifiedMethod(new MethodResolutionContext(), pos, env, location, site, name, argtypes, typeargtypes);
1652 }
1653 private Symbol resolveQualifiedMethod(MethodResolutionContext resolveContext,
1654 DiagnosticPosition pos, Env<AttrContext> env,
1655 Symbol location, Type site, Name name, List<Type> argtypes,
1656 List<Type> typeargtypes) {
1657 MethodResolutionContext prevResolutionContext = currentResolutionContext;
1658 try {
1659 currentResolutionContext = resolveContext;
1660 Symbol sym = methodNotFound;
1661 List<MethodResolutionPhase> steps = methodResolutionSteps;
1662 while (steps.nonEmpty() &&
1663 steps.head.isApplicable(boxingEnabled, varargsEnabled) &&
1664 sym.kind >= ERRONEOUS) {
1665 currentResolutionContext.step = steps.head;
1666 sym = findMethod(env, site, name, argtypes, typeargtypes,
1667 steps.head.isBoxingRequired(),
1668 env.info.varArgs = steps.head.isVarargsRequired(), false);
1669 currentResolutionContext.resolutionCache.put(steps.head, sym);
1670 steps = steps.tail;
1671 }
1672 if (sym.kind >= AMBIGUOUS) {
1673 if (site.tsym.isPolymorphicSignatureGeneric()) {
1674 //polymorphic receiver - synthesize new method symbol
1675 env.info.varArgs = false;
1676 sym = findPolymorphicSignatureInstance(env,
1677 site, name, null, argtypes);
1678 }
1679 else {
1680 //if nothing is found return the 'first' error
1681 MethodResolutionPhase errPhase =
1682 currentResolutionContext.firstErroneousResolutionPhase();
1683 sym = access(currentResolutionContext.resolutionCache.get(errPhase),
1684 pos, location, site, name, true, argtypes, typeargtypes);
1685 env.info.varArgs = errPhase.isVarargsRequired;
1686 }
1687 } else if (allowMethodHandles && sym.isPolymorphicSignatureGeneric()) {
1688 //non-instantiated polymorphic signature - synthesize new method symbol
1689 env.info.varArgs = false;
1690 sym = findPolymorphicSignatureInstance(env,
1691 site, name, (MethodSymbol)sym, argtypes);
1692 }
1693 return sym;
1694 }
1695 finally {
1696 currentResolutionContext = prevResolutionContext;
1697 }
1698 }
1700 /** Find or create an implicit method of exactly the given type (after erasure).
1701 * Searches in a side table, not the main scope of the site.
1702 * This emulates the lookup process required by JSR 292 in JVM.
1703 * @param env Attribution environment
1704 * @param site The original type from where the selection takes place.
1705 * @param name The method's name.
1706 * @param spMethod A template for the implicit method, or null.
1707 * @param argtypes The required argument types.
1708 * @param typeargtypes The required type arguments.
1709 */
1710 Symbol findPolymorphicSignatureInstance(Env<AttrContext> env, Type site,
1711 Name name,
1712 MethodSymbol spMethod, // sig. poly. method or null if none
1713 List<Type> argtypes) {
1714 Type mtype = infer.instantiatePolymorphicSignatureInstance(env,
1715 site, name, spMethod, argtypes);
1716 long flags = ABSTRACT | HYPOTHETICAL | POLYMORPHIC_SIGNATURE |
1717 (spMethod != null ?
1718 spMethod.flags() & Flags.AccessFlags :
1719 Flags.PUBLIC | Flags.STATIC);
1720 Symbol m = null;
1721 for (Scope.Entry e = polymorphicSignatureScope.lookup(name);
1722 e.scope != null;
1723 e = e.next()) {
1724 Symbol sym = e.sym;
1725 if (types.isSameType(mtype, sym.type) &&
1726 (sym.flags() & Flags.STATIC) == (flags & Flags.STATIC) &&
1727 types.isSameType(sym.owner.type, site)) {
1728 m = sym;
1729 break;
1730 }
1731 }
1732 if (m == null) {
1733 // create the desired method
1734 m = new MethodSymbol(flags, name, mtype, site.tsym);
1735 polymorphicSignatureScope.enter(m);
1736 }
1737 return m;
1738 }
1740 /** Resolve a qualified method identifier, throw a fatal error if not
1741 * found.
1742 * @param pos The position to use for error reporting.
1743 * @param env The environment current at the method invocation.
1744 * @param site The type of the qualifying expression, in which
1745 * identifier is searched.
1746 * @param name The identifier's name.
1747 * @param argtypes The types of the invocation's value arguments.
1748 * @param typeargtypes The types of the invocation's type arguments.
1749 */
1750 public MethodSymbol resolveInternalMethod(DiagnosticPosition pos, Env<AttrContext> env,
1751 Type site, Name name,
1752 List<Type> argtypes,
1753 List<Type> typeargtypes) {
1754 MethodResolutionContext resolveContext = new MethodResolutionContext();
1755 resolveContext.internalResolution = true;
1756 Symbol sym = resolveQualifiedMethod(resolveContext, pos, env, site.tsym,
1757 site, name, argtypes, typeargtypes);
1758 if (sym.kind == MTH) return (MethodSymbol)sym;
1759 else throw new FatalError(
1760 diags.fragment("fatal.err.cant.locate.meth",
1761 name));
1762 }
1764 /** Resolve constructor.
1765 * @param pos The position to use for error reporting.
1766 * @param env The environment current at the constructor invocation.
1767 * @param site The type of class for which a constructor is searched.
1768 * @param argtypes The types of the constructor invocation's value
1769 * arguments.
1770 * @param typeargtypes The types of the constructor invocation's type
1771 * arguments.
1772 */
1773 Symbol resolveConstructor(DiagnosticPosition pos,
1774 Env<AttrContext> env,
1775 Type site,
1776 List<Type> argtypes,
1777 List<Type> typeargtypes) {
1778 return resolveConstructor(new MethodResolutionContext(), pos, env, site, argtypes, typeargtypes);
1779 }
1780 private Symbol resolveConstructor(MethodResolutionContext resolveContext,
1781 DiagnosticPosition pos,
1782 Env<AttrContext> env,
1783 Type site,
1784 List<Type> argtypes,
1785 List<Type> typeargtypes) {
1786 MethodResolutionContext prevResolutionContext = currentResolutionContext;
1787 try {
1788 currentResolutionContext = resolveContext;
1789 Symbol sym = methodNotFound;
1790 List<MethodResolutionPhase> steps = methodResolutionSteps;
1791 while (steps.nonEmpty() &&
1792 steps.head.isApplicable(boxingEnabled, varargsEnabled) &&
1793 sym.kind >= ERRONEOUS) {
1794 currentResolutionContext.step = steps.head;
1795 sym = findConstructor(pos, env, site, argtypes, typeargtypes,
1796 steps.head.isBoxingRequired(),
1797 env.info.varArgs = steps.head.isVarargsRequired());
1798 currentResolutionContext.resolutionCache.put(steps.head, sym);
1799 steps = steps.tail;
1800 }
1801 if (sym.kind >= AMBIGUOUS) {//if nothing is found return the 'first' error
1802 MethodResolutionPhase errPhase = currentResolutionContext.firstErroneousResolutionPhase();
1803 sym = access(currentResolutionContext.resolutionCache.get(errPhase),
1804 pos, site, names.init, true, argtypes, typeargtypes);
1805 env.info.varArgs = errPhase.isVarargsRequired();
1806 }
1807 return sym;
1808 }
1809 finally {
1810 currentResolutionContext = prevResolutionContext;
1811 }
1812 }
1814 /** Resolve constructor using diamond inference.
1815 * @param pos The position to use for error reporting.
1816 * @param env The environment current at the constructor invocation.
1817 * @param site The type of class for which a constructor is searched.
1818 * The scope of this class has been touched in attribution.
1819 * @param argtypes The types of the constructor invocation's value
1820 * arguments.
1821 * @param typeargtypes The types of the constructor invocation's type
1822 * arguments.
1823 */
1824 Symbol resolveDiamond(DiagnosticPosition pos,
1825 Env<AttrContext> env,
1826 Type site,
1827 List<Type> argtypes,
1828 List<Type> typeargtypes) {
1829 MethodResolutionContext prevResolutionContext = currentResolutionContext;
1830 try {
1831 currentResolutionContext = new MethodResolutionContext();
1832 Symbol sym = methodNotFound;
1833 List<MethodResolutionPhase> steps = methodResolutionSteps;
1834 while (steps.nonEmpty() &&
1835 steps.head.isApplicable(boxingEnabled, varargsEnabled) &&
1836 sym.kind >= ERRONEOUS) {
1837 currentResolutionContext.step = steps.head;
1838 sym = findDiamond(env, site, argtypes, typeargtypes,
1839 steps.head.isBoxingRequired(),
1840 env.info.varArgs = steps.head.isVarargsRequired());
1841 currentResolutionContext.resolutionCache.put(steps.head, sym);
1842 steps = steps.tail;
1843 }
1844 if (sym.kind >= AMBIGUOUS) {
1845 final JCDiagnostic details = sym.kind == WRONG_MTH ?
1846 currentResolutionContext.candidates.head.details :
1847 null;
1848 Symbol errSym = new ResolveError(WRONG_MTH, "diamond error") {
1849 @Override
1850 JCDiagnostic getDiagnostic(DiagnosticType dkind, DiagnosticPosition pos,
1851 Symbol location, Type site, Name name, List<Type> argtypes, List<Type> typeargtypes) {
1852 String key = details == null ?
1853 "cant.apply.diamond" :
1854 "cant.apply.diamond.1";
1855 return diags.create(dkind, log.currentSource(), pos, key,
1856 diags.fragment("diamond", site.tsym), details);
1857 }
1858 };
1859 MethodResolutionPhase errPhase = currentResolutionContext.firstErroneousResolutionPhase();
1860 sym = access(errSym, pos, site, names.init, true, argtypes, typeargtypes);
1861 env.info.varArgs = errPhase.isVarargsRequired();
1862 }
1863 return sym;
1864 }
1865 finally {
1866 currentResolutionContext = prevResolutionContext;
1867 }
1868 }
1870 /** This method scans all the constructor symbol in a given class scope -
1871 * assuming that the original scope contains a constructor of the kind:
1872 * Foo(X x, Y y), where X,Y are class type-variables declared in Foo,
1873 * a method check is executed against the modified constructor type:
1874 * <X,Y>Foo<X,Y>(X x, Y y). This is crucial in order to enable diamond
1875 * inference. The inferred return type of the synthetic constructor IS
1876 * the inferred type for the diamond operator.
1877 */
1878 private Symbol findDiamond(Env<AttrContext> env,
1879 Type site,
1880 List<Type> argtypes,
1881 List<Type> typeargtypes,
1882 boolean allowBoxing,
1883 boolean useVarargs) {
1884 Symbol bestSoFar = methodNotFound;
1885 for (Scope.Entry e = site.tsym.members().lookup(names.init);
1886 e.scope != null;
1887 e = e.next()) {
1888 //- System.out.println(" e " + e.sym);
1889 if (e.sym.kind == MTH &&
1890 (e.sym.flags_field & SYNTHETIC) == 0) {
1891 List<Type> oldParams = e.sym.type.tag == FORALL ?
1892 ((ForAll)e.sym.type).tvars :
1893 List.<Type>nil();
1894 Type constrType = new ForAll(site.tsym.type.getTypeArguments().appendList(oldParams),
1895 types.createMethodTypeWithReturn(e.sym.type.asMethodType(), site));
1896 bestSoFar = selectBest(env, site, argtypes, typeargtypes,
1897 new MethodSymbol(e.sym.flags(), names.init, constrType, site.tsym),
1898 bestSoFar,
1899 allowBoxing,
1900 useVarargs,
1901 false);
1902 }
1903 }
1904 return bestSoFar;
1905 }
1907 /** Resolve constructor.
1908 * @param pos The position to use for error reporting.
1909 * @param env The environment current at the constructor invocation.
1910 * @param site The type of class for which a constructor is searched.
1911 * @param argtypes The types of the constructor invocation's value
1912 * arguments.
1913 * @param typeargtypes The types of the constructor invocation's type
1914 * arguments.
1915 * @param allowBoxing Allow boxing and varargs conversions.
1916 * @param useVarargs Box trailing arguments into an array for varargs.
1917 */
1918 Symbol resolveConstructor(DiagnosticPosition pos, Env<AttrContext> env,
1919 Type site, List<Type> argtypes,
1920 List<Type> typeargtypes,
1921 boolean allowBoxing,
1922 boolean useVarargs) {
1923 MethodResolutionContext prevResolutionContext = currentResolutionContext;
1924 try {
1925 currentResolutionContext = new MethodResolutionContext();
1926 return findConstructor(pos, env, site, argtypes, typeargtypes, allowBoxing, useVarargs);
1927 }
1928 finally {
1929 currentResolutionContext = prevResolutionContext;
1930 }
1931 }
1933 Symbol findConstructor(DiagnosticPosition pos, Env<AttrContext> env,
1934 Type site, List<Type> argtypes,
1935 List<Type> typeargtypes,
1936 boolean allowBoxing,
1937 boolean useVarargs) {
1938 Symbol sym = findMethod(env, site,
1939 names.init, argtypes,
1940 typeargtypes, allowBoxing,
1941 useVarargs, false);
1942 chk.checkDeprecated(pos, env.info.scope.owner, sym);
1943 return sym;
1944 }
1946 /** Resolve a constructor, throw a fatal error if not found.
1947 * @param pos The position to use for error reporting.
1948 * @param env The environment current at the method invocation.
1949 * @param site The type to be constructed.
1950 * @param argtypes The types of the invocation's value arguments.
1951 * @param typeargtypes The types of the invocation's type arguments.
1952 */
1953 public MethodSymbol resolveInternalConstructor(DiagnosticPosition pos, Env<AttrContext> env,
1954 Type site,
1955 List<Type> argtypes,
1956 List<Type> typeargtypes) {
1957 MethodResolutionContext resolveContext = new MethodResolutionContext();
1958 resolveContext.internalResolution = true;
1959 Symbol sym = resolveConstructor(resolveContext, pos, env, site, argtypes, typeargtypes);
1960 if (sym.kind == MTH) return (MethodSymbol)sym;
1961 else throw new FatalError(
1962 diags.fragment("fatal.err.cant.locate.ctor", site));
1963 }
1965 /** Resolve operator.
1966 * @param pos The position to use for error reporting.
1967 * @param optag The tag of the operation tree.
1968 * @param env The environment current at the operation.
1969 * @param argtypes The types of the operands.
1970 */
1971 Symbol resolveOperator(DiagnosticPosition pos, JCTree.Tag optag,
1972 Env<AttrContext> env, List<Type> argtypes) {
1973 MethodResolutionContext prevResolutionContext = currentResolutionContext;
1974 try {
1975 currentResolutionContext = new MethodResolutionContext();
1976 Name name = treeinfo.operatorName(optag);
1977 Symbol sym = findMethod(env, syms.predefClass.type, name, argtypes,
1978 null, false, false, true);
1979 if (boxingEnabled && sym.kind >= WRONG_MTHS)
1980 sym = findMethod(env, syms.predefClass.type, name, argtypes,
1981 null, true, false, true);
1982 return access(sym, pos, env.enclClass.sym.type, name,
1983 false, argtypes, null);
1984 }
1985 finally {
1986 currentResolutionContext = prevResolutionContext;
1987 }
1988 }
1990 /** Resolve operator.
1991 * @param pos The position to use for error reporting.
1992 * @param optag The tag of the operation tree.
1993 * @param env The environment current at the operation.
1994 * @param arg The type of the operand.
1995 */
1996 Symbol resolveUnaryOperator(DiagnosticPosition pos, JCTree.Tag optag, Env<AttrContext> env, Type arg) {
1997 return resolveOperator(pos, optag, env, List.of(arg));
1998 }
2000 /** Resolve binary operator.
2001 * @param pos The position to use for error reporting.
2002 * @param optag The tag of the operation tree.
2003 * @param env The environment current at the operation.
2004 * @param left The types of the left operand.
2005 * @param right The types of the right operand.
2006 */
2007 Symbol resolveBinaryOperator(DiagnosticPosition pos,
2008 JCTree.Tag optag,
2009 Env<AttrContext> env,
2010 Type left,
2011 Type right) {
2012 return resolveOperator(pos, optag, env, List.of(left, right));
2013 }
2015 /**
2016 * Resolve `c.name' where name == this or name == super.
2017 * @param pos The position to use for error reporting.
2018 * @param env The environment current at the expression.
2019 * @param c The qualifier.
2020 * @param name The identifier's name.
2021 */
2022 Symbol resolveSelf(DiagnosticPosition pos,
2023 Env<AttrContext> env,
2024 TypeSymbol c,
2025 Name name) {
2026 Env<AttrContext> env1 = env;
2027 boolean staticOnly = false;
2028 while (env1.outer != null) {
2029 if (isStatic(env1)) staticOnly = true;
2030 if (env1.enclClass.sym == c) {
2031 Symbol sym = env1.info.scope.lookup(name).sym;
2032 if (sym != null) {
2033 if (staticOnly) sym = new StaticError(sym);
2034 return access(sym, pos, env.enclClass.sym.type,
2035 name, true);
2036 }
2037 }
2038 if ((env1.enclClass.sym.flags() & STATIC) != 0) staticOnly = true;
2039 env1 = env1.outer;
2040 }
2041 log.error(pos, "not.encl.class", c);
2042 return syms.errSymbol;
2043 }
2045 /**
2046 * Resolve `c.this' for an enclosing class c that contains the
2047 * named member.
2048 * @param pos The position to use for error reporting.
2049 * @param env The environment current at the expression.
2050 * @param member The member that must be contained in the result.
2051 */
2052 Symbol resolveSelfContaining(DiagnosticPosition pos,
2053 Env<AttrContext> env,
2054 Symbol member,
2055 boolean isSuperCall) {
2056 Name name = names._this;
2057 Env<AttrContext> env1 = isSuperCall ? env.outer : env;
2058 boolean staticOnly = false;
2059 if (env1 != null) {
2060 while (env1 != null && env1.outer != null) {
2061 if (isStatic(env1)) staticOnly = true;
2062 if (env1.enclClass.sym.isSubClass(member.owner, types)) {
2063 Symbol sym = env1.info.scope.lookup(name).sym;
2064 if (sym != null) {
2065 if (staticOnly) sym = new StaticError(sym);
2066 return access(sym, pos, env.enclClass.sym.type,
2067 name, true);
2068 }
2069 }
2070 if ((env1.enclClass.sym.flags() & STATIC) != 0)
2071 staticOnly = true;
2072 env1 = env1.outer;
2073 }
2074 }
2075 log.error(pos, "encl.class.required", member);
2076 return syms.errSymbol;
2077 }
2079 /**
2080 * Resolve an appropriate implicit this instance for t's container.
2081 * JLS 8.8.5.1 and 15.9.2
2082 */
2083 Type resolveImplicitThis(DiagnosticPosition pos, Env<AttrContext> env, Type t) {
2084 return resolveImplicitThis(pos, env, t, false);
2085 }
2087 Type resolveImplicitThis(DiagnosticPosition pos, Env<AttrContext> env, Type t, boolean isSuperCall) {
2088 Type thisType = (((t.tsym.owner.kind & (MTH|VAR)) != 0)
2089 ? resolveSelf(pos, env, t.getEnclosingType().tsym, names._this)
2090 : resolveSelfContaining(pos, env, t.tsym, isSuperCall)).type;
2091 if (env.info.isSelfCall && thisType.tsym == env.enclClass.sym)
2092 log.error(pos, "cant.ref.before.ctor.called", "this");
2093 return thisType;
2094 }
2096 /* ***************************************************************************
2097 * ResolveError classes, indicating error situations when accessing symbols
2098 ****************************************************************************/
2100 //used by TransTypes when checking target type of synthetic cast
2101 public void logAccessErrorInternal(Env<AttrContext> env, JCTree tree, Type type) {
2102 AccessError error = new AccessError(env, env.enclClass.type, type.tsym);
2103 logResolveError(error, tree.pos(), env.enclClass.sym, env.enclClass.type, null, null, null);
2104 }
2105 //where
2106 private void logResolveError(ResolveError error,
2107 DiagnosticPosition pos,
2108 Symbol location,
2109 Type site,
2110 Name name,
2111 List<Type> argtypes,
2112 List<Type> typeargtypes) {
2113 JCDiagnostic d = error.getDiagnostic(JCDiagnostic.DiagnosticType.ERROR,
2114 pos, location, site, name, argtypes, typeargtypes);
2115 if (d != null) {
2116 d.setFlag(DiagnosticFlag.RESOLVE_ERROR);
2117 log.report(d);
2118 }
2119 }
2121 private final LocalizedString noArgs = new LocalizedString("compiler.misc.no.args");
2123 public Object methodArguments(List<Type> argtypes) {
2124 return argtypes == null || argtypes.isEmpty() ? noArgs : argtypes;
2125 }
2127 /**
2128 * Root class for resolution errors. Subclass of ResolveError
2129 * represent a different kinds of resolution error - as such they must
2130 * specify how they map into concrete compiler diagnostics.
2131 */
2132 private abstract class ResolveError extends Symbol {
2134 /** The name of the kind of error, for debugging only. */
2135 final String debugName;
2137 ResolveError(int kind, String debugName) {
2138 super(kind, 0, null, null, null);
2139 this.debugName = debugName;
2140 }
2142 @Override
2143 public <R, P> R accept(ElementVisitor<R, P> v, P p) {
2144 throw new AssertionError();
2145 }
2147 @Override
2148 public String toString() {
2149 return debugName;
2150 }
2152 @Override
2153 public boolean exists() {
2154 return false;
2155 }
2157 /**
2158 * Create an external representation for this erroneous symbol to be
2159 * used during attribution - by default this returns the symbol of a
2160 * brand new error type which stores the original type found
2161 * during resolution.
2162 *
2163 * @param name the name used during resolution
2164 * @param location the location from which the symbol is accessed
2165 */
2166 protected Symbol access(Name name, TypeSymbol location) {
2167 return types.createErrorType(name, location, syms.errSymbol.type).tsym;
2168 }
2170 /**
2171 * Create a diagnostic representing this resolution error.
2172 *
2173 * @param dkind The kind of the diagnostic to be created (e.g error).
2174 * @param pos The position to be used for error reporting.
2175 * @param site The original type from where the selection took place.
2176 * @param name The name of the symbol to be resolved.
2177 * @param argtypes The invocation's value arguments,
2178 * if we looked for a method.
2179 * @param typeargtypes The invocation's type arguments,
2180 * if we looked for a method.
2181 */
2182 abstract JCDiagnostic getDiagnostic(JCDiagnostic.DiagnosticType dkind,
2183 DiagnosticPosition pos,
2184 Symbol location,
2185 Type site,
2186 Name name,
2187 List<Type> argtypes,
2188 List<Type> typeargtypes);
2190 /**
2191 * A name designates an operator if it consists
2192 * of a non-empty sequence of operator symbols +-~!/*%&|^<>=
2193 */
2194 boolean isOperator(Name name) {
2195 int i = 0;
2196 while (i < name.getByteLength() &&
2197 "+-~!*/%&|^<>=".indexOf(name.getByteAt(i)) >= 0) i++;
2198 return i > 0 && i == name.getByteLength();
2199 }
2200 }
2202 /**
2203 * This class is the root class of all resolution errors caused by
2204 * an invalid symbol being found during resolution.
2205 */
2206 abstract class InvalidSymbolError extends ResolveError {
2208 /** The invalid symbol found during resolution */
2209 Symbol sym;
2211 InvalidSymbolError(int kind, Symbol sym, String debugName) {
2212 super(kind, debugName);
2213 this.sym = sym;
2214 }
2216 @Override
2217 public boolean exists() {
2218 return true;
2219 }
2221 @Override
2222 public String toString() {
2223 return super.toString() + " wrongSym=" + sym;
2224 }
2226 @Override
2227 public Symbol access(Name name, TypeSymbol location) {
2228 if (sym.kind >= AMBIGUOUS)
2229 return ((ResolveError)sym).access(name, location);
2230 else if ((sym.kind & ERRONEOUS) == 0 && (sym.kind & TYP) != 0)
2231 return types.createErrorType(name, location, sym.type).tsym;
2232 else
2233 return sym;
2234 }
2235 }
2237 /**
2238 * InvalidSymbolError error class indicating that a symbol matching a
2239 * given name does not exists in a given site.
2240 */
2241 class SymbolNotFoundError extends ResolveError {
2243 SymbolNotFoundError(int kind) {
2244 super(kind, "symbol not found error");
2245 }
2247 @Override
2248 JCDiagnostic getDiagnostic(JCDiagnostic.DiagnosticType dkind,
2249 DiagnosticPosition pos,
2250 Symbol location,
2251 Type site,
2252 Name name,
2253 List<Type> argtypes,
2254 List<Type> typeargtypes) {
2255 argtypes = argtypes == null ? List.<Type>nil() : argtypes;
2256 typeargtypes = typeargtypes == null ? List.<Type>nil() : typeargtypes;
2257 if (name == names.error)
2258 return null;
2260 if (isOperator(name)) {
2261 boolean isUnaryOp = argtypes.size() == 1;
2262 String key = argtypes.size() == 1 ?
2263 "operator.cant.be.applied" :
2264 "operator.cant.be.applied.1";
2265 Type first = argtypes.head;
2266 Type second = !isUnaryOp ? argtypes.tail.head : null;
2267 return diags.create(dkind, log.currentSource(), pos,
2268 key, name, first, second);
2269 }
2270 boolean hasLocation = false;
2271 if (location == null) {
2272 location = site.tsym;
2273 }
2274 if (!location.name.isEmpty()) {
2275 if (location.kind == PCK && !site.tsym.exists()) {
2276 return diags.create(dkind, log.currentSource(), pos,
2277 "doesnt.exist", location);
2278 }
2279 hasLocation = !location.name.equals(names._this) &&
2280 !location.name.equals(names._super);
2281 }
2282 boolean isConstructor = kind == ABSENT_MTH &&
2283 name == names.table.names.init;
2284 KindName kindname = isConstructor ? KindName.CONSTRUCTOR : absentKind(kind);
2285 Name idname = isConstructor ? site.tsym.name : name;
2286 String errKey = getErrorKey(kindname, typeargtypes.nonEmpty(), hasLocation);
2287 if (hasLocation) {
2288 return diags.create(dkind, log.currentSource(), pos,
2289 errKey, kindname, idname, //symbol kindname, name
2290 typeargtypes, argtypes, //type parameters and arguments (if any)
2291 getLocationDiag(location, site)); //location kindname, type
2292 }
2293 else {
2294 return diags.create(dkind, log.currentSource(), pos,
2295 errKey, kindname, idname, //symbol kindname, name
2296 typeargtypes, argtypes); //type parameters and arguments (if any)
2297 }
2298 }
2299 //where
2300 private String getErrorKey(KindName kindname, boolean hasTypeArgs, boolean hasLocation) {
2301 String key = "cant.resolve";
2302 String suffix = hasLocation ? ".location" : "";
2303 switch (kindname) {
2304 case METHOD:
2305 case CONSTRUCTOR: {
2306 suffix += ".args";
2307 suffix += hasTypeArgs ? ".params" : "";
2308 }
2309 }
2310 return key + suffix;
2311 }
2312 private JCDiagnostic getLocationDiag(Symbol location, Type site) {
2313 if (location.kind == VAR) {
2314 return diags.fragment("location.1",
2315 kindName(location),
2316 location,
2317 location.type);
2318 } else {
2319 return diags.fragment("location",
2320 typeKindName(site),
2321 site,
2322 null);
2323 }
2324 }
2325 }
2327 /**
2328 * InvalidSymbolError error class indicating that a given symbol
2329 * (either a method, a constructor or an operand) is not applicable
2330 * given an actual arguments/type argument list.
2331 */
2332 class InapplicableSymbolError extends ResolveError {
2334 InapplicableSymbolError() {
2335 super(WRONG_MTH, "inapplicable symbol error");
2336 }
2338 protected InapplicableSymbolError(int kind, String debugName) {
2339 super(kind, debugName);
2340 }
2342 @Override
2343 public String toString() {
2344 return super.toString();
2345 }
2347 @Override
2348 public boolean exists() {
2349 return true;
2350 }
2352 @Override
2353 JCDiagnostic getDiagnostic(JCDiagnostic.DiagnosticType dkind,
2354 DiagnosticPosition pos,
2355 Symbol location,
2356 Type site,
2357 Name name,
2358 List<Type> argtypes,
2359 List<Type> typeargtypes) {
2360 if (name == names.error)
2361 return null;
2363 if (isOperator(name)) {
2364 boolean isUnaryOp = argtypes.size() == 1;
2365 String key = argtypes.size() == 1 ?
2366 "operator.cant.be.applied" :
2367 "operator.cant.be.applied.1";
2368 Type first = argtypes.head;
2369 Type second = !isUnaryOp ? argtypes.tail.head : null;
2370 return diags.create(dkind, log.currentSource(), pos,
2371 key, name, first, second);
2372 }
2373 else {
2374 Candidate c = errCandidate();
2375 Symbol ws = c.sym.asMemberOf(site, types);
2376 return diags.create(dkind, log.currentSource(), pos,
2377 "cant.apply.symbol" + (c.details != null ? ".1" : ""),
2378 kindName(ws),
2379 ws.name == names.init ? ws.owner.name : ws.name,
2380 methodArguments(ws.type.getParameterTypes()),
2381 methodArguments(argtypes),
2382 kindName(ws.owner),
2383 ws.owner.type,
2384 c.details);
2385 }
2386 }
2388 @Override
2389 public Symbol access(Name name, TypeSymbol location) {
2390 return types.createErrorType(name, location, syms.errSymbol.type).tsym;
2391 }
2393 protected boolean shouldReport(Candidate c) {
2394 return !c.isApplicable() &&
2395 (((c.sym.flags() & VARARGS) != 0 && c.step == VARARITY) ||
2396 (c.sym.flags() & VARARGS) == 0 && c.step == (boxingEnabled ? BOX : BASIC));
2397 }
2399 private Candidate errCandidate() {
2400 for (Candidate c : currentResolutionContext.candidates) {
2401 if (shouldReport(c)) {
2402 return c;
2403 }
2404 }
2405 Assert.error();
2406 return null;
2407 }
2408 }
2410 /**
2411 * ResolveError error class indicating that a set of symbols
2412 * (either methods, constructors or operands) is not applicable
2413 * given an actual arguments/type argument list.
2414 */
2415 class InapplicableSymbolsError extends InapplicableSymbolError {
2417 InapplicableSymbolsError() {
2418 super(WRONG_MTHS, "inapplicable symbols");
2419 }
2421 @Override
2422 JCDiagnostic getDiagnostic(JCDiagnostic.DiagnosticType dkind,
2423 DiagnosticPosition pos,
2424 Symbol location,
2425 Type site,
2426 Name name,
2427 List<Type> argtypes,
2428 List<Type> typeargtypes) {
2429 if (currentResolutionContext.candidates.nonEmpty()) {
2430 JCDiagnostic err = diags.create(dkind,
2431 log.currentSource(),
2432 pos,
2433 "cant.apply.symbols",
2434 name == names.init ? KindName.CONSTRUCTOR : absentKind(kind),
2435 getName(),
2436 argtypes);
2437 return new JCDiagnostic.MultilineDiagnostic(err, candidateDetails(site));
2438 } else {
2439 return new SymbolNotFoundError(ABSENT_MTH).getDiagnostic(dkind, pos,
2440 location, site, name, argtypes, typeargtypes);
2441 }
2442 }
2444 //where
2445 List<JCDiagnostic> candidateDetails(Type site) {
2446 List<JCDiagnostic> details = List.nil();
2447 for (Candidate c : currentResolutionContext.candidates) {
2448 if (!shouldReport(c)) continue;
2449 JCDiagnostic detailDiag = diags.fragment("inapplicable.method",
2450 Kinds.kindName(c.sym),
2451 c.sym.location(site, types),
2452 c.sym.asMemberOf(site, types),
2453 c.details);
2454 details = details.prepend(detailDiag);
2455 }
2456 return details.reverse();
2457 }
2459 private Name getName() {
2460 Symbol sym = currentResolutionContext.candidates.head.sym;
2461 return sym.name == names.init ?
2462 sym.owner.name :
2463 sym.name;
2464 }
2465 }
2467 /**
2468 * An InvalidSymbolError error class indicating that a symbol is not
2469 * accessible from a given site
2470 */
2471 class AccessError extends InvalidSymbolError {
2473 private Env<AttrContext> env;
2474 private Type site;
2476 AccessError(Symbol sym) {
2477 this(null, null, sym);
2478 }
2480 AccessError(Env<AttrContext> env, Type site, Symbol sym) {
2481 super(HIDDEN, sym, "access error");
2482 this.env = env;
2483 this.site = site;
2484 if (debugResolve)
2485 log.error("proc.messager", sym + " @ " + site + " is inaccessible.");
2486 }
2488 @Override
2489 public boolean exists() {
2490 return false;
2491 }
2493 @Override
2494 JCDiagnostic getDiagnostic(JCDiagnostic.DiagnosticType dkind,
2495 DiagnosticPosition pos,
2496 Symbol location,
2497 Type site,
2498 Name name,
2499 List<Type> argtypes,
2500 List<Type> typeargtypes) {
2501 if (sym.owner.type.tag == ERROR)
2502 return null;
2504 if (sym.name == names.init && sym.owner != site.tsym) {
2505 return new SymbolNotFoundError(ABSENT_MTH).getDiagnostic(dkind,
2506 pos, location, site, name, argtypes, typeargtypes);
2507 }
2508 else if ((sym.flags() & PUBLIC) != 0
2509 || (env != null && this.site != null
2510 && !isAccessible(env, this.site))) {
2511 return diags.create(dkind, log.currentSource(),
2512 pos, "not.def.access.class.intf.cant.access",
2513 sym, sym.location());
2514 }
2515 else if ((sym.flags() & (PRIVATE | PROTECTED)) != 0) {
2516 return diags.create(dkind, log.currentSource(),
2517 pos, "report.access", sym,
2518 asFlagSet(sym.flags() & (PRIVATE | PROTECTED)),
2519 sym.location());
2520 }
2521 else {
2522 return diags.create(dkind, log.currentSource(),
2523 pos, "not.def.public.cant.access", sym, sym.location());
2524 }
2525 }
2526 }
2528 /**
2529 * InvalidSymbolError error class indicating that an instance member
2530 * has erroneously been accessed from a static context.
2531 */
2532 class StaticError extends InvalidSymbolError {
2534 StaticError(Symbol sym) {
2535 super(STATICERR, sym, "static error");
2536 }
2538 @Override
2539 JCDiagnostic getDiagnostic(JCDiagnostic.DiagnosticType dkind,
2540 DiagnosticPosition pos,
2541 Symbol location,
2542 Type site,
2543 Name name,
2544 List<Type> argtypes,
2545 List<Type> typeargtypes) {
2546 Symbol errSym = ((sym.kind == TYP && sym.type.tag == CLASS)
2547 ? types.erasure(sym.type).tsym
2548 : sym);
2549 return diags.create(dkind, log.currentSource(), pos,
2550 "non-static.cant.be.ref", kindName(sym), errSym);
2551 }
2552 }
2554 /**
2555 * InvalidSymbolError error class indicating that a pair of symbols
2556 * (either methods, constructors or operands) are ambiguous
2557 * given an actual arguments/type argument list.
2558 */
2559 class AmbiguityError extends InvalidSymbolError {
2561 /** The other maximally specific symbol */
2562 Symbol sym2;
2564 AmbiguityError(Symbol sym1, Symbol sym2) {
2565 super(AMBIGUOUS, sym1, "ambiguity error");
2566 this.sym2 = sym2;
2567 }
2569 @Override
2570 JCDiagnostic getDiagnostic(JCDiagnostic.DiagnosticType dkind,
2571 DiagnosticPosition pos,
2572 Symbol location,
2573 Type site,
2574 Name name,
2575 List<Type> argtypes,
2576 List<Type> typeargtypes) {
2577 AmbiguityError pair = this;
2578 while (true) {
2579 if (pair.sym.kind == AMBIGUOUS)
2580 pair = (AmbiguityError)pair.sym;
2581 else if (pair.sym2.kind == AMBIGUOUS)
2582 pair = (AmbiguityError)pair.sym2;
2583 else break;
2584 }
2585 Name sname = pair.sym.name;
2586 if (sname == names.init) sname = pair.sym.owner.name;
2587 return diags.create(dkind, log.currentSource(),
2588 pos, "ref.ambiguous", sname,
2589 kindName(pair.sym),
2590 pair.sym,
2591 pair.sym.location(site, types),
2592 kindName(pair.sym2),
2593 pair.sym2,
2594 pair.sym2.location(site, types));
2595 }
2596 }
2598 enum MethodResolutionPhase {
2599 BASIC(false, false),
2600 BOX(true, false),
2601 VARARITY(true, true);
2603 boolean isBoxingRequired;
2604 boolean isVarargsRequired;
2606 MethodResolutionPhase(boolean isBoxingRequired, boolean isVarargsRequired) {
2607 this.isBoxingRequired = isBoxingRequired;
2608 this.isVarargsRequired = isVarargsRequired;
2609 }
2611 public boolean isBoxingRequired() {
2612 return isBoxingRequired;
2613 }
2615 public boolean isVarargsRequired() {
2616 return isVarargsRequired;
2617 }
2619 public boolean isApplicable(boolean boxingEnabled, boolean varargsEnabled) {
2620 return (varargsEnabled || !isVarargsRequired) &&
2621 (boxingEnabled || !isBoxingRequired);
2622 }
2623 }
2625 final List<MethodResolutionPhase> methodResolutionSteps = List.of(BASIC, BOX, VARARITY);
2627 /**
2628 * A resolution context is used to keep track of intermediate results of
2629 * overload resolution, such as list of method that are not applicable
2630 * (used to generate more precise diagnostics) and so on. Resolution contexts
2631 * can be nested - this means that when each overload resolution routine should
2632 * work within the resolution context it created.
2633 */
2634 class MethodResolutionContext {
2636 private List<Candidate> candidates = List.nil();
2638 private Map<MethodResolutionPhase, Symbol> resolutionCache =
2639 new EnumMap<MethodResolutionPhase, Symbol>(MethodResolutionPhase.class);
2641 private MethodResolutionPhase step = null;
2643 private boolean internalResolution = false;
2645 private MethodResolutionPhase firstErroneousResolutionPhase() {
2646 MethodResolutionPhase bestSoFar = BASIC;
2647 Symbol sym = methodNotFound;
2648 List<MethodResolutionPhase> steps = methodResolutionSteps;
2649 while (steps.nonEmpty() &&
2650 steps.head.isApplicable(boxingEnabled, varargsEnabled) &&
2651 sym.kind >= WRONG_MTHS) {
2652 sym = resolutionCache.get(steps.head);
2653 bestSoFar = steps.head;
2654 steps = steps.tail;
2655 }
2656 return bestSoFar;
2657 }
2659 void addInapplicableCandidate(Symbol sym, JCDiagnostic details) {
2660 Candidate c = new Candidate(currentResolutionContext.step, sym, details, null);
2661 if (!candidates.contains(c))
2662 candidates = candidates.append(c);
2663 }
2665 void addApplicableCandidate(Symbol sym, Type mtype) {
2666 Candidate c = new Candidate(currentResolutionContext.step, sym, null, mtype);
2667 candidates = candidates.append(c);
2668 }
2670 /**
2671 * This class represents an overload resolution candidate. There are two
2672 * kinds of candidates: applicable methods and inapplicable methods;
2673 * applicable methods have a pointer to the instantiated method type,
2674 * while inapplicable candidates contain further details about the
2675 * reason why the method has been considered inapplicable.
2676 */
2677 class Candidate {
2679 final MethodResolutionPhase step;
2680 final Symbol sym;
2681 final JCDiagnostic details;
2682 final Type mtype;
2684 private Candidate(MethodResolutionPhase step, Symbol sym, JCDiagnostic details, Type mtype) {
2685 this.step = step;
2686 this.sym = sym;
2687 this.details = details;
2688 this.mtype = mtype;
2689 }
2691 @Override
2692 public boolean equals(Object o) {
2693 if (o instanceof Candidate) {
2694 Symbol s1 = this.sym;
2695 Symbol s2 = ((Candidate)o).sym;
2696 if ((s1 != s2 &&
2697 (s1.overrides(s2, s1.owner.type.tsym, types, false) ||
2698 (s2.overrides(s1, s2.owner.type.tsym, types, false)))) ||
2699 ((s1.isConstructor() || s2.isConstructor()) && s1.owner != s2.owner))
2700 return true;
2701 }
2702 return false;
2703 }
2705 boolean isApplicable() {
2706 return mtype != null;
2707 }
2708 }
2709 }
2711 MethodResolutionContext currentResolutionContext = null;
2712 }
