Fri, 12 Nov 2010 12:33:52 +0000
6999067: cast for invokeExact call gets redundant cast to <type> warnings
Summary: Xlint:cast should not report cast used in order to specify target type in polymorphic signature calls
Reviewed-by: jjg
1 /*
2 * Copyright (c) 1999, 2008, 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.util.*;
29 import com.sun.tools.javac.util.JCDiagnostic.DiagnosticPosition;
30 import com.sun.tools.javac.code.*;
31 import com.sun.tools.javac.jvm.*;
32 import com.sun.tools.javac.tree.*;
33 import com.sun.tools.javac.api.Formattable.LocalizedString;
34 import static com.sun.tools.javac.comp.Resolve.MethodResolutionPhase.*;
36 import com.sun.tools.javac.code.Type.*;
37 import com.sun.tools.javac.code.Symbol.*;
38 import com.sun.tools.javac.tree.JCTree.*;
40 import static com.sun.tools.javac.code.Flags.*;
41 import static com.sun.tools.javac.code.Kinds.*;
42 import static com.sun.tools.javac.code.TypeTags.*;
43 import com.sun.tools.javac.util.JCDiagnostic.DiagnosticFlag;
44 import com.sun.tools.javac.util.JCDiagnostic.DiagnosticType;
45 import javax.lang.model.element.ElementVisitor;
47 import java.util.Map;
48 import java.util.HashMap;
50 /** Helper class for name resolution, used mostly by the attribution phase.
51 *
52 * <p><b>This is NOT part of any supported API.
53 * If you write code that depends on this, you do so at your own risk.
54 * This code and its internal interfaces are subject to change or
55 * deletion without notice.</b>
56 */
57 public class Resolve {
58 protected static final Context.Key<Resolve> resolveKey =
59 new Context.Key<Resolve>();
61 Names names;
62 Log log;
63 Symtab syms;
64 Check chk;
65 Infer infer;
66 ClassReader reader;
67 TreeInfo treeinfo;
68 Types types;
69 JCDiagnostic.Factory diags;
70 public final boolean boxingEnabled; // = source.allowBoxing();
71 public final boolean varargsEnabled; // = source.allowVarargs();
72 public final boolean allowMethodHandles;
73 public final boolean allowInvokeDynamic;
74 public final boolean allowTransitionalJSR292;
75 private final boolean debugResolve;
77 Scope polymorphicSignatureScope;
79 public static Resolve instance(Context context) {
80 Resolve instance = context.get(resolveKey);
81 if (instance == null)
82 instance = new Resolve(context);
83 return instance;
84 }
86 protected Resolve(Context context) {
87 context.put(resolveKey, this);
88 syms = Symtab.instance(context);
90 varNotFound = new
91 SymbolNotFoundError(ABSENT_VAR);
92 wrongMethod = new
93 InapplicableSymbolError(syms.errSymbol);
94 wrongMethods = new
95 InapplicableSymbolsError(syms.errSymbol);
96 methodNotFound = new
97 SymbolNotFoundError(ABSENT_MTH);
98 typeNotFound = new
99 SymbolNotFoundError(ABSENT_TYP);
101 names = Names.instance(context);
102 log = Log.instance(context);
103 chk = Check.instance(context);
104 infer = Infer.instance(context);
105 reader = ClassReader.instance(context);
106 treeinfo = TreeInfo.instance(context);
107 types = Types.instance(context);
108 diags = JCDiagnostic.Factory.instance(context);
109 Source source = Source.instance(context);
110 boxingEnabled = source.allowBoxing();
111 varargsEnabled = source.allowVarargs();
112 Options options = Options.instance(context);
113 debugResolve = options.isSet("debugresolve");
114 allowTransitionalJSR292 = options.isSet("allowTransitionalJSR292");
115 Target target = Target.instance(context);
116 allowMethodHandles = allowTransitionalJSR292 ||
117 target.hasMethodHandles();
118 allowInvokeDynamic = (allowTransitionalJSR292 ||
119 target.hasInvokedynamic()) &&
120 options.isSet("invokedynamic");
121 polymorphicSignatureScope = new Scope(syms.noSymbol);
123 inapplicableMethodException = new InapplicableMethodException(diags);
124 }
126 /** error symbols, which are returned when resolution fails
127 */
128 final SymbolNotFoundError varNotFound;
129 final InapplicableSymbolError wrongMethod;
130 final InapplicableSymbolsError wrongMethods;
131 final SymbolNotFoundError methodNotFound;
132 final SymbolNotFoundError typeNotFound;
134 /* ************************************************************************
135 * Identifier resolution
136 *************************************************************************/
138 /** An environment is "static" if its static level is greater than
139 * the one of its outer environment
140 */
141 static boolean isStatic(Env<AttrContext> env) {
142 return env.info.staticLevel > env.outer.info.staticLevel;
143 }
145 /** An environment is an "initializer" if it is a constructor or
146 * an instance initializer.
147 */
148 static boolean isInitializer(Env<AttrContext> env) {
149 Symbol owner = env.info.scope.owner;
150 return owner.isConstructor() ||
151 owner.owner.kind == TYP &&
152 (owner.kind == VAR ||
153 owner.kind == MTH && (owner.flags() & BLOCK) != 0) &&
154 (owner.flags() & STATIC) == 0;
155 }
157 /** Is class accessible in given evironment?
158 * @param env The current environment.
159 * @param c The class whose accessibility is checked.
160 */
161 public boolean isAccessible(Env<AttrContext> env, TypeSymbol c) {
162 return isAccessible(env, c, false);
163 }
165 public boolean isAccessible(Env<AttrContext> env, TypeSymbol c, boolean checkInner) {
166 boolean isAccessible = false;
167 switch ((short)(c.flags() & AccessFlags)) {
168 case PRIVATE:
169 isAccessible =
170 env.enclClass.sym.outermostClass() ==
171 c.owner.outermostClass();
172 break;
173 case 0:
174 isAccessible =
175 env.toplevel.packge == c.owner // fast special case
176 ||
177 env.toplevel.packge == c.packge()
178 ||
179 // Hack: this case is added since synthesized default constructors
180 // of anonymous classes should be allowed to access
181 // classes which would be inaccessible otherwise.
182 env.enclMethod != null &&
183 (env.enclMethod.mods.flags & ANONCONSTR) != 0;
184 break;
185 default: // error recovery
186 case PUBLIC:
187 isAccessible = true;
188 break;
189 case PROTECTED:
190 isAccessible =
191 env.toplevel.packge == c.owner // fast special case
192 ||
193 env.toplevel.packge == c.packge()
194 ||
195 isInnerSubClass(env.enclClass.sym, c.owner);
196 break;
197 }
198 return (checkInner == false || c.type.getEnclosingType() == Type.noType) ?
199 isAccessible :
200 isAccessible & isAccessible(env, c.type.getEnclosingType(), checkInner);
201 }
202 //where
203 /** Is given class a subclass of given base class, or an inner class
204 * of a subclass?
205 * Return null if no such class exists.
206 * @param c The class which is the subclass or is contained in it.
207 * @param base The base class
208 */
209 private boolean isInnerSubClass(ClassSymbol c, Symbol base) {
210 while (c != null && !c.isSubClass(base, types)) {
211 c = c.owner.enclClass();
212 }
213 return c != null;
214 }
216 boolean isAccessible(Env<AttrContext> env, Type t) {
217 return isAccessible(env, t, false);
218 }
220 boolean isAccessible(Env<AttrContext> env, Type t, boolean checkInner) {
221 return (t.tag == ARRAY)
222 ? isAccessible(env, types.elemtype(t))
223 : isAccessible(env, t.tsym, checkInner);
224 }
226 /** Is symbol accessible as a member of given type in given evironment?
227 * @param env The current environment.
228 * @param site The type of which the tested symbol is regarded
229 * as a member.
230 * @param sym The symbol.
231 */
232 public boolean isAccessible(Env<AttrContext> env, Type site, Symbol sym) {
233 return isAccessible(env, site, sym, false);
234 }
235 public boolean isAccessible(Env<AttrContext> env, Type site, Symbol sym, boolean checkInner) {
236 if (sym.name == names.init && sym.owner != site.tsym) return false;
237 ClassSymbol sub;
238 switch ((short)(sym.flags() & AccessFlags)) {
239 case PRIVATE:
240 return
241 (env.enclClass.sym == sym.owner // fast special case
242 ||
243 env.enclClass.sym.outermostClass() ==
244 sym.owner.outermostClass())
245 &&
246 sym.isInheritedIn(site.tsym, types);
247 case 0:
248 return
249 (env.toplevel.packge == sym.owner.owner // fast special case
250 ||
251 env.toplevel.packge == sym.packge())
252 &&
253 isAccessible(env, site, checkInner)
254 &&
255 sym.isInheritedIn(site.tsym, types)
256 &&
257 notOverriddenIn(site, sym);
258 case PROTECTED:
259 return
260 (env.toplevel.packge == sym.owner.owner // fast special case
261 ||
262 env.toplevel.packge == sym.packge()
263 ||
264 isProtectedAccessible(sym, env.enclClass.sym, site)
265 ||
266 // OK to select instance method or field from 'super' or type name
267 // (but type names should be disallowed elsewhere!)
268 env.info.selectSuper && (sym.flags() & STATIC) == 0 && sym.kind != TYP)
269 &&
270 isAccessible(env, site, checkInner)
271 &&
272 notOverriddenIn(site, sym);
273 default: // this case includes erroneous combinations as well
274 return isAccessible(env, site, checkInner) && notOverriddenIn(site, sym);
275 }
276 }
277 //where
278 /* `sym' is accessible only if not overridden by
279 * another symbol which is a member of `site'
280 * (because, if it is overridden, `sym' is not strictly
281 * speaking a member of `site'). A polymorphic signature method
282 * cannot be overridden (e.g. MH.invokeExact(Object[])).
283 */
284 private boolean notOverriddenIn(Type site, Symbol sym) {
285 if (sym.kind != MTH || sym.isConstructor() || sym.isStatic())
286 return true;
287 else {
288 Symbol s2 = ((MethodSymbol)sym).implementation(site.tsym, types, true);
289 return (s2 == null || s2 == sym ||
290 s2.isPolymorphicSignatureGeneric() ||
291 !types.isSubSignature(types.memberType(site, s2), types.memberType(site, sym)));
292 }
293 }
294 //where
295 /** Is given protected symbol accessible if it is selected from given site
296 * and the selection takes place in given class?
297 * @param sym The symbol with protected access
298 * @param c The class where the access takes place
299 * @site The type of the qualifier
300 */
301 private
302 boolean isProtectedAccessible(Symbol sym, ClassSymbol c, Type site) {
303 while (c != null &&
304 !(c.isSubClass(sym.owner, types) &&
305 (c.flags() & INTERFACE) == 0 &&
306 // In JLS 2e 6.6.2.1, the subclass restriction applies
307 // only to instance fields and methods -- types are excluded
308 // regardless of whether they are declared 'static' or not.
309 ((sym.flags() & STATIC) != 0 || sym.kind == TYP || site.tsym.isSubClass(c, types))))
310 c = c.owner.enclClass();
311 return c != null;
312 }
314 /** Try to instantiate the type of a method so that it fits
315 * given type arguments and argument types. If succesful, return
316 * the method's instantiated type, else return null.
317 * The instantiation will take into account an additional leading
318 * formal parameter if the method is an instance method seen as a member
319 * of un underdetermined site In this case, we treat site as an additional
320 * parameter and the parameters of the class containing the method as
321 * additional type variables that get instantiated.
322 *
323 * @param env The current environment
324 * @param site The type of which the method is a member.
325 * @param m The method symbol.
326 * @param argtypes The invocation's given value arguments.
327 * @param typeargtypes The invocation's given type arguments.
328 * @param allowBoxing Allow boxing conversions of arguments.
329 * @param useVarargs Box trailing arguments into an array for varargs.
330 */
331 Type rawInstantiate(Env<AttrContext> env,
332 Type site,
333 Symbol m,
334 List<Type> argtypes,
335 List<Type> typeargtypes,
336 boolean allowBoxing,
337 boolean useVarargs,
338 Warner warn)
339 throws Infer.InferenceException {
340 boolean polymorphicSignature = (m.isPolymorphicSignatureGeneric() && allowMethodHandles) ||
341 isTransitionalDynamicCallSite(site, m);
342 if (useVarargs && (m.flags() & VARARGS) == 0)
343 throw inapplicableMethodException.setMessage(null);
344 Type mt = types.memberType(site, m);
346 // tvars is the list of formal type variables for which type arguments
347 // need to inferred.
348 List<Type> tvars = env.info.tvars;
349 if (typeargtypes == null) typeargtypes = List.nil();
350 if (allowTransitionalJSR292 && polymorphicSignature && typeargtypes.nonEmpty()) {
351 //transitional 292 call sites might have wrong number of targs
352 }
353 else if (mt.tag != FORALL && typeargtypes.nonEmpty()) {
354 // This is not a polymorphic method, but typeargs are supplied
355 // which is fine, see JLS3 15.12.2.1
356 } else if (mt.tag == FORALL && typeargtypes.nonEmpty()) {
357 ForAll pmt = (ForAll) mt;
358 if (typeargtypes.length() != pmt.tvars.length())
359 throw inapplicableMethodException.setMessage("arg.length.mismatch"); // not enough args
360 // Check type arguments are within bounds
361 List<Type> formals = pmt.tvars;
362 List<Type> actuals = typeargtypes;
363 while (formals.nonEmpty() && actuals.nonEmpty()) {
364 List<Type> bounds = types.subst(types.getBounds((TypeVar)formals.head),
365 pmt.tvars, typeargtypes);
366 for (; bounds.nonEmpty(); bounds = bounds.tail)
367 if (!types.isSubtypeUnchecked(actuals.head, bounds.head, warn))
368 throw inapplicableMethodException.setMessage("explicit.param.do.not.conform.to.bounds",actuals.head, bounds);
369 formals = formals.tail;
370 actuals = actuals.tail;
371 }
372 mt = types.subst(pmt.qtype, pmt.tvars, typeargtypes);
373 } else if (mt.tag == FORALL) {
374 ForAll pmt = (ForAll) mt;
375 List<Type> tvars1 = types.newInstances(pmt.tvars);
376 tvars = tvars.appendList(tvars1);
377 mt = types.subst(pmt.qtype, pmt.tvars, tvars1);
378 }
380 // find out whether we need to go the slow route via infer
381 boolean instNeeded = tvars.tail != null || /*inlined: tvars.nonEmpty()*/
382 polymorphicSignature;
383 for (List<Type> l = argtypes;
384 l.tail != null/*inlined: l.nonEmpty()*/ && !instNeeded;
385 l = l.tail) {
386 if (l.head.tag == FORALL) instNeeded = true;
387 }
389 if (instNeeded)
390 return polymorphicSignature ?
391 infer.instantiatePolymorphicSignatureInstance(env, site, m.name, (MethodSymbol)m, argtypes, typeargtypes) :
392 infer.instantiateMethod(env,
393 tvars,
394 (MethodType)mt,
395 m,
396 argtypes,
397 allowBoxing,
398 useVarargs,
399 warn);
401 checkRawArgumentsAcceptable(argtypes, mt.getParameterTypes(),
402 allowBoxing, useVarargs, warn);
403 return mt;
404 }
406 boolean isTransitionalDynamicCallSite(Type site, Symbol sym) {
407 return allowTransitionalJSR292 && // old logic that doesn't use annotations
408 !sym.isPolymorphicSignatureInstance() &&
409 ((allowMethodHandles && site == syms.methodHandleType && // invokeExact, invokeGeneric, invoke
410 (sym.name == names.invoke && sym.isPolymorphicSignatureGeneric())) ||
411 (site == syms.invokeDynamicType && allowInvokeDynamic)); // InvokeDynamic.XYZ
412 }
414 /** Same but returns null instead throwing a NoInstanceException
415 */
416 Type instantiate(Env<AttrContext> env,
417 Type site,
418 Symbol m,
419 List<Type> argtypes,
420 List<Type> typeargtypes,
421 boolean allowBoxing,
422 boolean useVarargs,
423 Warner warn) {
424 try {
425 return rawInstantiate(env, site, m, argtypes, typeargtypes,
426 allowBoxing, useVarargs, warn);
427 } catch (InapplicableMethodException ex) {
428 return null;
429 }
430 }
432 /** Check if a parameter list accepts a list of args.
433 */
434 boolean argumentsAcceptable(List<Type> argtypes,
435 List<Type> formals,
436 boolean allowBoxing,
437 boolean useVarargs,
438 Warner warn) {
439 try {
440 checkRawArgumentsAcceptable(argtypes, formals, allowBoxing, useVarargs, warn);
441 return true;
442 } catch (InapplicableMethodException ex) {
443 return false;
444 }
445 }
446 void checkRawArgumentsAcceptable(List<Type> argtypes,
447 List<Type> formals,
448 boolean allowBoxing,
449 boolean useVarargs,
450 Warner warn) {
451 Type varargsFormal = useVarargs ? formals.last() : null;
452 if (varargsFormal == null &&
453 argtypes.size() != formals.size()) {
454 throw inapplicableMethodException.setMessage("arg.length.mismatch"); // not enough args
455 }
457 while (argtypes.nonEmpty() && formals.head != varargsFormal) {
458 boolean works = allowBoxing
459 ? types.isConvertible(argtypes.head, formals.head, warn)
460 : types.isSubtypeUnchecked(argtypes.head, formals.head, warn);
461 if (!works)
462 throw inapplicableMethodException.setMessage("no.conforming.assignment.exists",
463 argtypes.head,
464 formals.head);
465 argtypes = argtypes.tail;
466 formals = formals.tail;
467 }
469 if (formals.head != varargsFormal)
470 throw inapplicableMethodException.setMessage("arg.length.mismatch"); // not enough args
472 if (useVarargs) {
473 Type elt = types.elemtype(varargsFormal);
474 while (argtypes.nonEmpty()) {
475 if (!types.isConvertible(argtypes.head, elt, warn))
476 throw inapplicableMethodException.setMessage("varargs.argument.mismatch",
477 argtypes.head,
478 elt);
479 argtypes = argtypes.tail;
480 }
481 }
482 return;
483 }
484 // where
485 public static class InapplicableMethodException extends RuntimeException {
486 private static final long serialVersionUID = 0;
488 JCDiagnostic diagnostic;
489 JCDiagnostic.Factory diags;
491 InapplicableMethodException(JCDiagnostic.Factory diags) {
492 this.diagnostic = null;
493 this.diags = diags;
494 }
495 InapplicableMethodException setMessage(String key) {
496 this.diagnostic = key != null ? diags.fragment(key) : null;
497 return this;
498 }
499 InapplicableMethodException setMessage(String key, Object... args) {
500 this.diagnostic = key != null ? diags.fragment(key, args) : null;
501 return this;
502 }
504 public JCDiagnostic getDiagnostic() {
505 return diagnostic;
506 }
507 }
508 private final InapplicableMethodException inapplicableMethodException;
510 /* ***************************************************************************
511 * Symbol lookup
512 * the following naming conventions for arguments are used
513 *
514 * env is the environment where the symbol was mentioned
515 * site is the type of which the symbol is a member
516 * name is the symbol's name
517 * if no arguments are given
518 * argtypes are the value arguments, if we search for a method
519 *
520 * If no symbol was found, a ResolveError detailing the problem is returned.
521 ****************************************************************************/
523 /** Find field. Synthetic fields are always skipped.
524 * @param env The current environment.
525 * @param site The original type from where the selection takes place.
526 * @param name The name of the field.
527 * @param c The class to search for the field. This is always
528 * a superclass or implemented interface of site's class.
529 */
530 Symbol findField(Env<AttrContext> env,
531 Type site,
532 Name name,
533 TypeSymbol c) {
534 while (c.type.tag == TYPEVAR)
535 c = c.type.getUpperBound().tsym;
536 Symbol bestSoFar = varNotFound;
537 Symbol sym;
538 Scope.Entry e = c.members().lookup(name);
539 while (e.scope != null) {
540 if (e.sym.kind == VAR && (e.sym.flags_field & SYNTHETIC) == 0) {
541 return isAccessible(env, site, e.sym)
542 ? e.sym : new AccessError(env, site, e.sym);
543 }
544 e = e.next();
545 }
546 Type st = types.supertype(c.type);
547 if (st != null && (st.tag == CLASS || st.tag == TYPEVAR)) {
548 sym = findField(env, site, name, st.tsym);
549 if (sym.kind < bestSoFar.kind) bestSoFar = sym;
550 }
551 for (List<Type> l = types.interfaces(c.type);
552 bestSoFar.kind != AMBIGUOUS && l.nonEmpty();
553 l = l.tail) {
554 sym = findField(env, site, name, l.head.tsym);
555 if (bestSoFar.kind < AMBIGUOUS && sym.kind < AMBIGUOUS &&
556 sym.owner != bestSoFar.owner)
557 bestSoFar = new AmbiguityError(bestSoFar, sym);
558 else if (sym.kind < bestSoFar.kind)
559 bestSoFar = sym;
560 }
561 return bestSoFar;
562 }
564 /** Resolve a field identifier, throw a fatal error if not found.
565 * @param pos The position to use for error reporting.
566 * @param env The environment current at the method invocation.
567 * @param site The type of the qualifying expression, in which
568 * identifier is searched.
569 * @param name The identifier's name.
570 */
571 public VarSymbol resolveInternalField(DiagnosticPosition pos, Env<AttrContext> env,
572 Type site, Name name) {
573 Symbol sym = findField(env, site, name, site.tsym);
574 if (sym.kind == VAR) return (VarSymbol)sym;
575 else throw new FatalError(
576 diags.fragment("fatal.err.cant.locate.field",
577 name));
578 }
580 /** Find unqualified variable or field with given name.
581 * Synthetic fields always skipped.
582 * @param env The current environment.
583 * @param name The name of the variable or field.
584 */
585 Symbol findVar(Env<AttrContext> env, Name name) {
586 Symbol bestSoFar = varNotFound;
587 Symbol sym;
588 Env<AttrContext> env1 = env;
589 boolean staticOnly = false;
590 while (env1.outer != null) {
591 if (isStatic(env1)) staticOnly = true;
592 Scope.Entry e = env1.info.scope.lookup(name);
593 while (e.scope != null &&
594 (e.sym.kind != VAR ||
595 (e.sym.flags_field & SYNTHETIC) != 0))
596 e = e.next();
597 sym = (e.scope != null)
598 ? e.sym
599 : findField(
600 env1, env1.enclClass.sym.type, name, env1.enclClass.sym);
601 if (sym.exists()) {
602 if (staticOnly &&
603 sym.kind == VAR &&
604 sym.owner.kind == TYP &&
605 (sym.flags() & STATIC) == 0)
606 return new StaticError(sym);
607 else
608 return sym;
609 } else if (sym.kind < bestSoFar.kind) {
610 bestSoFar = sym;
611 }
613 if ((env1.enclClass.sym.flags() & STATIC) != 0) staticOnly = true;
614 env1 = env1.outer;
615 }
617 sym = findField(env, syms.predefClass.type, name, syms.predefClass);
618 if (sym.exists())
619 return sym;
620 if (bestSoFar.exists())
621 return bestSoFar;
623 Scope.Entry e = env.toplevel.namedImportScope.lookup(name);
624 for (; e.scope != null; e = e.next()) {
625 sym = e.sym;
626 Type origin = e.getOrigin().owner.type;
627 if (sym.kind == VAR) {
628 if (e.sym.owner.type != origin)
629 sym = sym.clone(e.getOrigin().owner);
630 return isAccessible(env, origin, sym)
631 ? sym : new AccessError(env, origin, sym);
632 }
633 }
635 Symbol origin = null;
636 e = env.toplevel.starImportScope.lookup(name);
637 for (; e.scope != null; e = e.next()) {
638 sym = e.sym;
639 if (sym.kind != VAR)
640 continue;
641 // invariant: sym.kind == VAR
642 if (bestSoFar.kind < AMBIGUOUS && sym.owner != bestSoFar.owner)
643 return new AmbiguityError(bestSoFar, sym);
644 else if (bestSoFar.kind >= VAR) {
645 origin = e.getOrigin().owner;
646 bestSoFar = isAccessible(env, origin.type, sym)
647 ? sym : new AccessError(env, origin.type, sym);
648 }
649 }
650 if (bestSoFar.kind == VAR && bestSoFar.owner.type != origin.type)
651 return bestSoFar.clone(origin);
652 else
653 return bestSoFar;
654 }
656 Warner noteWarner = new Warner();
658 /** Select the best method for a call site among two choices.
659 * @param env The current environment.
660 * @param site The original type from where the
661 * selection takes place.
662 * @param argtypes The invocation's value arguments,
663 * @param typeargtypes The invocation's type arguments,
664 * @param sym Proposed new best match.
665 * @param bestSoFar Previously found best match.
666 * @param allowBoxing Allow boxing conversions of arguments.
667 * @param useVarargs Box trailing arguments into an array for varargs.
668 */
669 @SuppressWarnings("fallthrough")
670 Symbol selectBest(Env<AttrContext> env,
671 Type site,
672 List<Type> argtypes,
673 List<Type> typeargtypes,
674 Symbol sym,
675 Symbol bestSoFar,
676 boolean allowBoxing,
677 boolean useVarargs,
678 boolean operator) {
679 if (sym.kind == ERR) return bestSoFar;
680 if (!sym.isInheritedIn(site.tsym, types)) return bestSoFar;
681 assert sym.kind < AMBIGUOUS;
682 try {
683 rawInstantiate(env, site, sym, argtypes, typeargtypes,
684 allowBoxing, useVarargs, Warner.noWarnings);
685 } catch (InapplicableMethodException ex) {
686 switch (bestSoFar.kind) {
687 case ABSENT_MTH:
688 return wrongMethod.setWrongSym(sym, ex.getDiagnostic());
689 case WRONG_MTH:
690 wrongMethods.addCandidate(currentStep, wrongMethod.sym, wrongMethod.explanation);
691 case WRONG_MTHS:
692 return wrongMethods.addCandidate(currentStep, sym, ex.getDiagnostic());
693 default:
694 return bestSoFar;
695 }
696 }
697 if (!isAccessible(env, site, sym)) {
698 return (bestSoFar.kind == ABSENT_MTH)
699 ? new AccessError(env, site, sym)
700 : bestSoFar;
701 }
702 return (bestSoFar.kind > AMBIGUOUS)
703 ? sym
704 : mostSpecific(sym, bestSoFar, env, site,
705 allowBoxing && operator, useVarargs);
706 }
708 /* Return the most specific of the two methods for a call,
709 * given that both are accessible and applicable.
710 * @param m1 A new candidate for most specific.
711 * @param m2 The previous most specific candidate.
712 * @param env The current environment.
713 * @param site The original type from where the selection
714 * takes place.
715 * @param allowBoxing Allow boxing conversions of arguments.
716 * @param useVarargs Box trailing arguments into an array for varargs.
717 */
718 Symbol mostSpecific(Symbol m1,
719 Symbol m2,
720 Env<AttrContext> env,
721 final Type site,
722 boolean allowBoxing,
723 boolean useVarargs) {
724 switch (m2.kind) {
725 case MTH:
726 if (m1 == m2) return m1;
727 Type mt1 = types.memberType(site, m1);
728 noteWarner.unchecked = false;
729 boolean m1SignatureMoreSpecific =
730 (instantiate(env, site, m2, types.lowerBoundArgtypes(mt1), null,
731 allowBoxing, false, noteWarner) != null ||
732 useVarargs && instantiate(env, site, m2, types.lowerBoundArgtypes(mt1), null,
733 allowBoxing, true, noteWarner) != null) &&
734 !noteWarner.unchecked;
735 Type mt2 = types.memberType(site, m2);
736 noteWarner.unchecked = false;
737 boolean m2SignatureMoreSpecific =
738 (instantiate(env, site, m1, types.lowerBoundArgtypes(mt2), null,
739 allowBoxing, false, noteWarner) != null ||
740 useVarargs && instantiate(env, site, m1, types.lowerBoundArgtypes(mt2), null,
741 allowBoxing, true, noteWarner) != null) &&
742 !noteWarner.unchecked;
743 if (m1SignatureMoreSpecific && m2SignatureMoreSpecific) {
744 if (!types.overrideEquivalent(mt1, mt2))
745 return new AmbiguityError(m1, m2);
746 // same signature; select (a) the non-bridge method, or
747 // (b) the one that overrides the other, or (c) the concrete
748 // one, or (d) merge both abstract signatures
749 if ((m1.flags() & BRIDGE) != (m2.flags() & BRIDGE)) {
750 return ((m1.flags() & BRIDGE) != 0) ? m2 : m1;
751 }
752 // if one overrides or hides the other, use it
753 TypeSymbol m1Owner = (TypeSymbol)m1.owner;
754 TypeSymbol m2Owner = (TypeSymbol)m2.owner;
755 if (types.asSuper(m1Owner.type, m2Owner) != null &&
756 ((m1.owner.flags_field & INTERFACE) == 0 ||
757 (m2.owner.flags_field & INTERFACE) != 0) &&
758 m1.overrides(m2, m1Owner, types, false))
759 return m1;
760 if (types.asSuper(m2Owner.type, m1Owner) != null &&
761 ((m2.owner.flags_field & INTERFACE) == 0 ||
762 (m1.owner.flags_field & INTERFACE) != 0) &&
763 m2.overrides(m1, m2Owner, types, false))
764 return m2;
765 boolean m1Abstract = (m1.flags() & ABSTRACT) != 0;
766 boolean m2Abstract = (m2.flags() & ABSTRACT) != 0;
767 if (m1Abstract && !m2Abstract) return m2;
768 if (m2Abstract && !m1Abstract) return m1;
769 // both abstract or both concrete
770 if (!m1Abstract && !m2Abstract)
771 return new AmbiguityError(m1, m2);
772 // check that both signatures have the same erasure
773 if (!types.isSameTypes(m1.erasure(types).getParameterTypes(),
774 m2.erasure(types).getParameterTypes()))
775 return new AmbiguityError(m1, m2);
776 // both abstract, neither overridden; merge throws clause and result type
777 Symbol mostSpecific;
778 Type result2 = mt2.getReturnType();
779 if (mt2.tag == FORALL)
780 result2 = types.subst(result2, ((ForAll)mt2).tvars, ((ForAll)mt1).tvars);
781 if (types.isSubtype(mt1.getReturnType(), result2)) {
782 mostSpecific = m1;
783 } else if (types.isSubtype(result2, mt1.getReturnType())) {
784 mostSpecific = m2;
785 } else {
786 // Theoretically, this can't happen, but it is possible
787 // due to error recovery or mixing incompatible class files
788 return new AmbiguityError(m1, m2);
789 }
790 MethodSymbol result = new MethodSymbol(
791 mostSpecific.flags(),
792 mostSpecific.name,
793 null,
794 mostSpecific.owner) {
795 @Override
796 public MethodSymbol implementation(TypeSymbol origin, Types types, boolean checkResult) {
797 if (origin == site.tsym)
798 return this;
799 else
800 return super.implementation(origin, types, checkResult);
801 }
802 };
803 result.type = (Type)mostSpecific.type.clone();
804 result.type.setThrown(chk.intersect(mt1.getThrownTypes(),
805 mt2.getThrownTypes()));
806 return result;
807 }
808 if (m1SignatureMoreSpecific) return m1;
809 if (m2SignatureMoreSpecific) return m2;
810 return new AmbiguityError(m1, m2);
811 case AMBIGUOUS:
812 AmbiguityError e = (AmbiguityError)m2;
813 Symbol err1 = mostSpecific(m1, e.sym, env, site, allowBoxing, useVarargs);
814 Symbol err2 = mostSpecific(m1, e.sym2, env, site, allowBoxing, useVarargs);
815 if (err1 == err2) return err1;
816 if (err1 == e.sym && err2 == e.sym2) return m2;
817 if (err1 instanceof AmbiguityError &&
818 err2 instanceof AmbiguityError &&
819 ((AmbiguityError)err1).sym == ((AmbiguityError)err2).sym)
820 return new AmbiguityError(m1, m2);
821 else
822 return new AmbiguityError(err1, err2);
823 default:
824 throw new AssertionError();
825 }
826 }
828 /** Find best qualified method matching given name, type and value
829 * arguments.
830 * @param env The current environment.
831 * @param site The original type from where the selection
832 * takes place.
833 * @param name The method's name.
834 * @param argtypes The method's value arguments.
835 * @param typeargtypes The method's type arguments
836 * @param allowBoxing Allow boxing conversions of arguments.
837 * @param useVarargs Box trailing arguments into an array for varargs.
838 */
839 Symbol findMethod(Env<AttrContext> env,
840 Type site,
841 Name name,
842 List<Type> argtypes,
843 List<Type> typeargtypes,
844 boolean allowBoxing,
845 boolean useVarargs,
846 boolean operator) {
847 Symbol bestSoFar = methodNotFound;
848 return findMethod(env,
849 site,
850 name,
851 argtypes,
852 typeargtypes,
853 site.tsym.type,
854 true,
855 bestSoFar,
856 allowBoxing,
857 useVarargs,
858 operator);
859 }
860 // where
861 private Symbol findMethod(Env<AttrContext> env,
862 Type site,
863 Name name,
864 List<Type> argtypes,
865 List<Type> typeargtypes,
866 Type intype,
867 boolean abstractok,
868 Symbol bestSoFar,
869 boolean allowBoxing,
870 boolean useVarargs,
871 boolean operator) {
872 for (Type ct = intype; ct.tag == CLASS || ct.tag == TYPEVAR; ct = types.supertype(ct)) {
873 while (ct.tag == TYPEVAR)
874 ct = ct.getUpperBound();
875 ClassSymbol c = (ClassSymbol)ct.tsym;
876 if ((c.flags() & (ABSTRACT | INTERFACE | ENUM)) == 0)
877 abstractok = false;
878 for (Scope.Entry e = c.members().lookup(name);
879 e.scope != null;
880 e = e.next()) {
881 //- System.out.println(" e " + e.sym);
882 if (e.sym.kind == MTH &&
883 (e.sym.flags_field & SYNTHETIC) == 0) {
884 bestSoFar = selectBest(env, site, argtypes, typeargtypes,
885 e.sym, bestSoFar,
886 allowBoxing,
887 useVarargs,
888 operator);
889 }
890 }
891 if (name == names.init)
892 break;
893 //- System.out.println(" - " + bestSoFar);
894 if (abstractok) {
895 Symbol concrete = methodNotFound;
896 if ((bestSoFar.flags() & ABSTRACT) == 0)
897 concrete = bestSoFar;
898 for (List<Type> l = types.interfaces(c.type);
899 l.nonEmpty();
900 l = l.tail) {
901 bestSoFar = findMethod(env, site, name, argtypes,
902 typeargtypes,
903 l.head, abstractok, bestSoFar,
904 allowBoxing, useVarargs, operator);
905 }
906 if (concrete != bestSoFar &&
907 concrete.kind < ERR && bestSoFar.kind < ERR &&
908 types.isSubSignature(concrete.type, bestSoFar.type))
909 bestSoFar = concrete;
910 }
911 }
912 return bestSoFar;
913 }
915 /** Find unqualified method matching given name, type and value arguments.
916 * @param env The current environment.
917 * @param name The method's name.
918 * @param argtypes The method's value arguments.
919 * @param typeargtypes The method's type arguments.
920 * @param allowBoxing Allow boxing conversions of arguments.
921 * @param useVarargs Box trailing arguments into an array for varargs.
922 */
923 Symbol findFun(Env<AttrContext> env, Name name,
924 List<Type> argtypes, List<Type> typeargtypes,
925 boolean allowBoxing, boolean useVarargs) {
926 Symbol bestSoFar = methodNotFound;
927 Symbol sym;
928 Env<AttrContext> env1 = env;
929 boolean staticOnly = false;
930 while (env1.outer != null) {
931 if (isStatic(env1)) staticOnly = true;
932 sym = findMethod(
933 env1, env1.enclClass.sym.type, name, argtypes, typeargtypes,
934 allowBoxing, useVarargs, false);
935 if (sym.exists()) {
936 if (staticOnly &&
937 sym.kind == MTH &&
938 sym.owner.kind == TYP &&
939 (sym.flags() & STATIC) == 0) return new StaticError(sym);
940 else return sym;
941 } else if (sym.kind < bestSoFar.kind) {
942 bestSoFar = sym;
943 }
944 if ((env1.enclClass.sym.flags() & STATIC) != 0) staticOnly = true;
945 env1 = env1.outer;
946 }
948 sym = findMethod(env, syms.predefClass.type, name, argtypes,
949 typeargtypes, allowBoxing, useVarargs, false);
950 if (sym.exists())
951 return sym;
953 Scope.Entry e = env.toplevel.namedImportScope.lookup(name);
954 for (; e.scope != null; e = e.next()) {
955 sym = e.sym;
956 Type origin = e.getOrigin().owner.type;
957 if (sym.kind == MTH) {
958 if (e.sym.owner.type != origin)
959 sym = sym.clone(e.getOrigin().owner);
960 if (!isAccessible(env, origin, sym))
961 sym = new AccessError(env, origin, sym);
962 bestSoFar = selectBest(env, origin,
963 argtypes, typeargtypes,
964 sym, bestSoFar,
965 allowBoxing, useVarargs, false);
966 }
967 }
968 if (bestSoFar.exists())
969 return bestSoFar;
971 e = env.toplevel.starImportScope.lookup(name);
972 for (; e.scope != null; e = e.next()) {
973 sym = e.sym;
974 Type origin = e.getOrigin().owner.type;
975 if (sym.kind == MTH) {
976 if (e.sym.owner.type != origin)
977 sym = sym.clone(e.getOrigin().owner);
978 if (!isAccessible(env, origin, sym))
979 sym = new AccessError(env, origin, sym);
980 bestSoFar = selectBest(env, origin,
981 argtypes, typeargtypes,
982 sym, bestSoFar,
983 allowBoxing, useVarargs, false);
984 }
985 }
986 return bestSoFar;
987 }
989 /** Load toplevel or member class with given fully qualified name and
990 * verify that it is accessible.
991 * @param env The current environment.
992 * @param name The fully qualified name of the class to be loaded.
993 */
994 Symbol loadClass(Env<AttrContext> env, Name name) {
995 try {
996 ClassSymbol c = reader.loadClass(name);
997 return isAccessible(env, c) ? c : new AccessError(c);
998 } catch (ClassReader.BadClassFile err) {
999 throw err;
1000 } catch (CompletionFailure ex) {
1001 return typeNotFound;
1002 }
1003 }
1005 /** Find qualified member type.
1006 * @param env The current environment.
1007 * @param site The original type from where the selection takes
1008 * place.
1009 * @param name The type's name.
1010 * @param c The class to search for the member type. This is
1011 * always a superclass or implemented interface of
1012 * site's class.
1013 */
1014 Symbol findMemberType(Env<AttrContext> env,
1015 Type site,
1016 Name name,
1017 TypeSymbol c) {
1018 Symbol bestSoFar = typeNotFound;
1019 Symbol sym;
1020 Scope.Entry e = c.members().lookup(name);
1021 while (e.scope != null) {
1022 if (e.sym.kind == TYP) {
1023 return isAccessible(env, site, e.sym)
1024 ? e.sym
1025 : new AccessError(env, site, e.sym);
1026 }
1027 e = e.next();
1028 }
1029 Type st = types.supertype(c.type);
1030 if (st != null && st.tag == CLASS) {
1031 sym = findMemberType(env, site, name, st.tsym);
1032 if (sym.kind < bestSoFar.kind) bestSoFar = sym;
1033 }
1034 for (List<Type> l = types.interfaces(c.type);
1035 bestSoFar.kind != AMBIGUOUS && l.nonEmpty();
1036 l = l.tail) {
1037 sym = findMemberType(env, site, name, l.head.tsym);
1038 if (bestSoFar.kind < AMBIGUOUS && sym.kind < AMBIGUOUS &&
1039 sym.owner != bestSoFar.owner)
1040 bestSoFar = new AmbiguityError(bestSoFar, sym);
1041 else if (sym.kind < bestSoFar.kind)
1042 bestSoFar = sym;
1043 }
1044 return bestSoFar;
1045 }
1047 /** Find a global type in given scope and load corresponding class.
1048 * @param env The current environment.
1049 * @param scope The scope in which to look for the type.
1050 * @param name The type's name.
1051 */
1052 Symbol findGlobalType(Env<AttrContext> env, Scope scope, Name name) {
1053 Symbol bestSoFar = typeNotFound;
1054 for (Scope.Entry e = scope.lookup(name); e.scope != null; e = e.next()) {
1055 Symbol sym = loadClass(env, e.sym.flatName());
1056 if (bestSoFar.kind == TYP && sym.kind == TYP &&
1057 bestSoFar != sym)
1058 return new AmbiguityError(bestSoFar, sym);
1059 else if (sym.kind < bestSoFar.kind)
1060 bestSoFar = sym;
1061 }
1062 return bestSoFar;
1063 }
1065 /** Find an unqualified type symbol.
1066 * @param env The current environment.
1067 * @param name The type's name.
1068 */
1069 Symbol findType(Env<AttrContext> env, Name name) {
1070 Symbol bestSoFar = typeNotFound;
1071 Symbol sym;
1072 boolean staticOnly = false;
1073 for (Env<AttrContext> env1 = env; env1.outer != null; env1 = env1.outer) {
1074 if (isStatic(env1)) staticOnly = true;
1075 for (Scope.Entry e = env1.info.scope.lookup(name);
1076 e.scope != null;
1077 e = e.next()) {
1078 if (e.sym.kind == TYP) {
1079 if (staticOnly &&
1080 e.sym.type.tag == TYPEVAR &&
1081 e.sym.owner.kind == TYP) return new StaticError(e.sym);
1082 return e.sym;
1083 }
1084 }
1086 sym = findMemberType(env1, env1.enclClass.sym.type, name,
1087 env1.enclClass.sym);
1088 if (staticOnly && sym.kind == TYP &&
1089 sym.type.tag == CLASS &&
1090 sym.type.getEnclosingType().tag == CLASS &&
1091 env1.enclClass.sym.type.isParameterized() &&
1092 sym.type.getEnclosingType().isParameterized())
1093 return new StaticError(sym);
1094 else if (sym.exists()) return sym;
1095 else if (sym.kind < bestSoFar.kind) bestSoFar = sym;
1097 JCClassDecl encl = env1.baseClause ? (JCClassDecl)env1.tree : env1.enclClass;
1098 if ((encl.sym.flags() & STATIC) != 0)
1099 staticOnly = true;
1100 }
1102 if (env.tree.getTag() != JCTree.IMPORT) {
1103 sym = findGlobalType(env, env.toplevel.namedImportScope, name);
1104 if (sym.exists()) return sym;
1105 else if (sym.kind < bestSoFar.kind) bestSoFar = sym;
1107 sym = findGlobalType(env, env.toplevel.packge.members(), name);
1108 if (sym.exists()) return sym;
1109 else if (sym.kind < bestSoFar.kind) bestSoFar = sym;
1111 sym = findGlobalType(env, env.toplevel.starImportScope, name);
1112 if (sym.exists()) return sym;
1113 else if (sym.kind < bestSoFar.kind) bestSoFar = sym;
1114 }
1116 return bestSoFar;
1117 }
1119 /** Find an unqualified identifier which matches a specified kind set.
1120 * @param env The current environment.
1121 * @param name The indentifier's name.
1122 * @param kind Indicates the possible symbol kinds
1123 * (a subset of VAL, TYP, PCK).
1124 */
1125 Symbol findIdent(Env<AttrContext> env, Name name, int kind) {
1126 Symbol bestSoFar = typeNotFound;
1127 Symbol sym;
1129 if ((kind & VAR) != 0) {
1130 sym = findVar(env, name);
1131 if (sym.exists()) return sym;
1132 else if (sym.kind < bestSoFar.kind) bestSoFar = sym;
1133 }
1135 if ((kind & TYP) != 0) {
1136 sym = findType(env, name);
1137 if (sym.exists()) return sym;
1138 else if (sym.kind < bestSoFar.kind) bestSoFar = sym;
1139 }
1141 if ((kind & PCK) != 0) return reader.enterPackage(name);
1142 else return bestSoFar;
1143 }
1145 /** Find an identifier in a package which matches a specified kind set.
1146 * @param env The current environment.
1147 * @param name The identifier's name.
1148 * @param kind Indicates the possible symbol kinds
1149 * (a nonempty subset of TYP, PCK).
1150 */
1151 Symbol findIdentInPackage(Env<AttrContext> env, TypeSymbol pck,
1152 Name name, int kind) {
1153 Name fullname = TypeSymbol.formFullName(name, pck);
1154 Symbol bestSoFar = typeNotFound;
1155 PackageSymbol pack = null;
1156 if ((kind & PCK) != 0) {
1157 pack = reader.enterPackage(fullname);
1158 if (pack.exists()) return pack;
1159 }
1160 if ((kind & TYP) != 0) {
1161 Symbol sym = loadClass(env, fullname);
1162 if (sym.exists()) {
1163 // don't allow programs to use flatnames
1164 if (name == sym.name) return sym;
1165 }
1166 else if (sym.kind < bestSoFar.kind) bestSoFar = sym;
1167 }
1168 return (pack != null) ? pack : bestSoFar;
1169 }
1171 /** Find an identifier among the members of a given type `site'.
1172 * @param env The current environment.
1173 * @param site The type containing the symbol to be found.
1174 * @param name The identifier's name.
1175 * @param kind Indicates the possible symbol kinds
1176 * (a subset of VAL, TYP).
1177 */
1178 Symbol findIdentInType(Env<AttrContext> env, Type site,
1179 Name name, int kind) {
1180 Symbol bestSoFar = typeNotFound;
1181 Symbol sym;
1182 if ((kind & VAR) != 0) {
1183 sym = findField(env, site, name, site.tsym);
1184 if (sym.exists()) return sym;
1185 else if (sym.kind < bestSoFar.kind) bestSoFar = sym;
1186 }
1188 if ((kind & TYP) != 0) {
1189 sym = findMemberType(env, site, name, site.tsym);
1190 if (sym.exists()) return sym;
1191 else if (sym.kind < bestSoFar.kind) bestSoFar = sym;
1192 }
1193 return bestSoFar;
1194 }
1196 /* ***************************************************************************
1197 * Access checking
1198 * The following methods convert ResolveErrors to ErrorSymbols, issuing
1199 * an error message in the process
1200 ****************************************************************************/
1202 /** If `sym' is a bad symbol: report error and return errSymbol
1203 * else pass through unchanged,
1204 * additional arguments duplicate what has been used in trying to find the
1205 * symbol (--> flyweight pattern). This improves performance since we
1206 * expect misses to happen frequently.
1207 *
1208 * @param sym The symbol that was found, or a ResolveError.
1209 * @param pos The position to use for error reporting.
1210 * @param site The original type from where the selection took place.
1211 * @param name The symbol's name.
1212 * @param argtypes The invocation's value arguments,
1213 * if we looked for a method.
1214 * @param typeargtypes The invocation's type arguments,
1215 * if we looked for a method.
1216 */
1217 Symbol access(Symbol sym,
1218 DiagnosticPosition pos,
1219 Type site,
1220 Name name,
1221 boolean qualified,
1222 List<Type> argtypes,
1223 List<Type> typeargtypes) {
1224 if (sym.kind >= AMBIGUOUS) {
1225 ResolveError errSym = (ResolveError)sym;
1226 if (!site.isErroneous() &&
1227 !Type.isErroneous(argtypes) &&
1228 (typeargtypes==null || !Type.isErroneous(typeargtypes)))
1229 logResolveError(errSym, pos, site, name, argtypes, typeargtypes);
1230 sym = errSym.access(name, qualified ? site.tsym : syms.noSymbol);
1231 }
1232 return sym;
1233 }
1235 /** Same as above, but without type arguments and arguments.
1236 */
1237 Symbol access(Symbol sym,
1238 DiagnosticPosition pos,
1239 Type site,
1240 Name name,
1241 boolean qualified) {
1242 if (sym.kind >= AMBIGUOUS)
1243 return access(sym, pos, site, name, qualified, List.<Type>nil(), null);
1244 else
1245 return sym;
1246 }
1248 /** Check that sym is not an abstract method.
1249 */
1250 void checkNonAbstract(DiagnosticPosition pos, Symbol sym) {
1251 if ((sym.flags() & ABSTRACT) != 0)
1252 log.error(pos, "abstract.cant.be.accessed.directly",
1253 kindName(sym), sym, sym.location());
1254 }
1256 /* ***************************************************************************
1257 * Debugging
1258 ****************************************************************************/
1260 /** print all scopes starting with scope s and proceeding outwards.
1261 * used for debugging.
1262 */
1263 public void printscopes(Scope s) {
1264 while (s != null) {
1265 if (s.owner != null)
1266 System.err.print(s.owner + ": ");
1267 for (Scope.Entry e = s.elems; e != null; e = e.sibling) {
1268 if ((e.sym.flags() & ABSTRACT) != 0)
1269 System.err.print("abstract ");
1270 System.err.print(e.sym + " ");
1271 }
1272 System.err.println();
1273 s = s.next;
1274 }
1275 }
1277 void printscopes(Env<AttrContext> env) {
1278 while (env.outer != null) {
1279 System.err.println("------------------------------");
1280 printscopes(env.info.scope);
1281 env = env.outer;
1282 }
1283 }
1285 public void printscopes(Type t) {
1286 while (t.tag == CLASS) {
1287 printscopes(t.tsym.members());
1288 t = types.supertype(t);
1289 }
1290 }
1292 /* ***************************************************************************
1293 * Name resolution
1294 * Naming conventions are as for symbol lookup
1295 * Unlike the find... methods these methods will report access errors
1296 ****************************************************************************/
1298 /** Resolve an unqualified (non-method) identifier.
1299 * @param pos The position to use for error reporting.
1300 * @param env The environment current at the identifier use.
1301 * @param name The identifier's name.
1302 * @param kind The set of admissible symbol kinds for the identifier.
1303 */
1304 Symbol resolveIdent(DiagnosticPosition pos, Env<AttrContext> env,
1305 Name name, int kind) {
1306 return access(
1307 findIdent(env, name, kind),
1308 pos, env.enclClass.sym.type, name, false);
1309 }
1311 /** Resolve an unqualified method identifier.
1312 * @param pos The position to use for error reporting.
1313 * @param env The environment current at the method invocation.
1314 * @param name The identifier's name.
1315 * @param argtypes The types of the invocation's value arguments.
1316 * @param typeargtypes The types of the invocation's type arguments.
1317 */
1318 Symbol resolveMethod(DiagnosticPosition pos,
1319 Env<AttrContext> env,
1320 Name name,
1321 List<Type> argtypes,
1322 List<Type> typeargtypes) {
1323 Symbol sym = startResolution();
1324 List<MethodResolutionPhase> steps = methodResolutionSteps;
1325 while (steps.nonEmpty() &&
1326 steps.head.isApplicable(boxingEnabled, varargsEnabled) &&
1327 sym.kind >= ERRONEOUS) {
1328 currentStep = steps.head;
1329 sym = findFun(env, name, argtypes, typeargtypes,
1330 steps.head.isBoxingRequired,
1331 env.info.varArgs = steps.head.isVarargsRequired);
1332 methodResolutionCache.put(steps.head, sym);
1333 steps = steps.tail;
1334 }
1335 if (sym.kind >= AMBIGUOUS) {//if nothing is found return the 'first' error
1336 MethodResolutionPhase errPhase =
1337 firstErroneousResolutionPhase();
1338 sym = access(methodResolutionCache.get(errPhase),
1339 pos, env.enclClass.sym.type, name, false, argtypes, typeargtypes);
1340 env.info.varArgs = errPhase.isVarargsRequired;
1341 }
1342 return sym;
1343 }
1345 private Symbol startResolution() {
1346 wrongMethod.clear();
1347 wrongMethods.clear();
1348 return methodNotFound;
1349 }
1351 /** Resolve a qualified method identifier
1352 * @param pos The position to use for error reporting.
1353 * @param env The environment current at the method invocation.
1354 * @param site The type of the qualifying expression, in which
1355 * identifier is searched.
1356 * @param name The identifier's name.
1357 * @param argtypes The types of the invocation's value arguments.
1358 * @param typeargtypes The types of the invocation's type arguments.
1359 */
1360 Symbol resolveQualifiedMethod(DiagnosticPosition pos, Env<AttrContext> env,
1361 Type site, Name name, List<Type> argtypes,
1362 List<Type> typeargtypes) {
1363 Symbol sym = startResolution();
1364 List<MethodResolutionPhase> steps = methodResolutionSteps;
1365 while (steps.nonEmpty() &&
1366 steps.head.isApplicable(boxingEnabled, varargsEnabled) &&
1367 sym.kind >= ERRONEOUS) {
1368 currentStep = steps.head;
1369 sym = findMethod(env, site, name, argtypes, typeargtypes,
1370 steps.head.isBoxingRequired(),
1371 env.info.varArgs = steps.head.isVarargsRequired(), false);
1372 methodResolutionCache.put(steps.head, sym);
1373 steps = steps.tail;
1374 }
1375 if (sym.kind >= AMBIGUOUS) {
1376 if (site.tsym.isPolymorphicSignatureGeneric() ||
1377 isTransitionalDynamicCallSite(site, sym)) {
1378 //polymorphic receiver - synthesize new method symbol
1379 env.info.varArgs = false;
1380 sym = findPolymorphicSignatureInstance(env,
1381 site, name, null, argtypes, typeargtypes);
1382 }
1383 else {
1384 //if nothing is found return the 'first' error
1385 MethodResolutionPhase errPhase =
1386 firstErroneousResolutionPhase();
1387 sym = access(methodResolutionCache.get(errPhase),
1388 pos, site, name, true, argtypes, typeargtypes);
1389 env.info.varArgs = errPhase.isVarargsRequired;
1390 }
1391 } else if (allowMethodHandles && sym.isPolymorphicSignatureGeneric()) {
1392 //non-instantiated polymorphic signature - synthesize new method symbol
1393 env.info.varArgs = false;
1394 sym = findPolymorphicSignatureInstance(env,
1395 site, name, (MethodSymbol)sym, argtypes, typeargtypes);
1396 }
1397 return sym;
1398 }
1400 /** Find or create an implicit method of exactly the given type (after erasure).
1401 * Searches in a side table, not the main scope of the site.
1402 * This emulates the lookup process required by JSR 292 in JVM.
1403 * @param env Attribution environment
1404 * @param site The original type from where the selection takes place.
1405 * @param name The method's name.
1406 * @param spMethod A template for the implicit method, or null.
1407 * @param argtypes The required argument types.
1408 * @param typeargtypes The required type arguments.
1409 */
1410 Symbol findPolymorphicSignatureInstance(Env<AttrContext> env, Type site,
1411 Name name,
1412 MethodSymbol spMethod, // sig. poly. method or null if none
1413 List<Type> argtypes,
1414 List<Type> typeargtypes) {
1415 if (typeargtypes.nonEmpty() && (site.tsym.isPolymorphicSignatureGeneric() ||
1416 (spMethod != null && spMethod.isPolymorphicSignatureGeneric()))) {
1417 log.warning(env.tree.pos(), "type.parameter.on.polymorphic.signature");
1418 }
1420 Type mtype = infer.instantiatePolymorphicSignatureInstance(env,
1421 site, name, spMethod, argtypes, typeargtypes);
1422 long flags = ABSTRACT | HYPOTHETICAL | POLYMORPHIC_SIGNATURE |
1423 (spMethod != null ?
1424 spMethod.flags() & Flags.AccessFlags :
1425 Flags.PUBLIC | Flags.STATIC);
1426 Symbol m = null;
1427 for (Scope.Entry e = polymorphicSignatureScope.lookup(name);
1428 e.scope != null;
1429 e = e.next()) {
1430 Symbol sym = e.sym;
1431 if (types.isSameType(mtype, sym.type) &&
1432 (sym.flags() & Flags.STATIC) == (flags & Flags.STATIC) &&
1433 types.isSameType(sym.owner.type, site)) {
1434 m = sym;
1435 break;
1436 }
1437 }
1438 if (m == null) {
1439 // create the desired method
1440 m = new MethodSymbol(flags, name, mtype, site.tsym);
1441 polymorphicSignatureScope.enter(m);
1442 }
1443 return m;
1444 }
1446 /** Resolve a qualified method identifier, throw a fatal error if not
1447 * found.
1448 * @param pos The position to use for error reporting.
1449 * @param env The environment current at the method invocation.
1450 * @param site The type of the qualifying expression, in which
1451 * identifier is searched.
1452 * @param name The identifier's name.
1453 * @param argtypes The types of the invocation's value arguments.
1454 * @param typeargtypes The types of the invocation's type arguments.
1455 */
1456 public MethodSymbol resolveInternalMethod(DiagnosticPosition pos, Env<AttrContext> env,
1457 Type site, Name name,
1458 List<Type> argtypes,
1459 List<Type> typeargtypes) {
1460 Symbol sym = resolveQualifiedMethod(
1461 pos, env, site, name, argtypes, typeargtypes);
1462 if (sym.kind == MTH) return (MethodSymbol)sym;
1463 else throw new FatalError(
1464 diags.fragment("fatal.err.cant.locate.meth",
1465 name));
1466 }
1468 /** Resolve constructor.
1469 * @param pos The position to use for error reporting.
1470 * @param env The environment current at the constructor invocation.
1471 * @param site The type of class for which a constructor is searched.
1472 * @param argtypes The types of the constructor invocation's value
1473 * arguments.
1474 * @param typeargtypes The types of the constructor invocation's type
1475 * arguments.
1476 */
1477 Symbol resolveConstructor(DiagnosticPosition pos,
1478 Env<AttrContext> env,
1479 Type site,
1480 List<Type> argtypes,
1481 List<Type> typeargtypes) {
1482 Symbol sym = startResolution();
1483 List<MethodResolutionPhase> steps = methodResolutionSteps;
1484 while (steps.nonEmpty() &&
1485 steps.head.isApplicable(boxingEnabled, varargsEnabled) &&
1486 sym.kind >= ERRONEOUS) {
1487 currentStep = steps.head;
1488 sym = resolveConstructor(pos, env, site, argtypes, typeargtypes,
1489 steps.head.isBoxingRequired(),
1490 env.info.varArgs = steps.head.isVarargsRequired());
1491 methodResolutionCache.put(steps.head, sym);
1492 steps = steps.tail;
1493 }
1494 if (sym.kind >= AMBIGUOUS) {//if nothing is found return the 'first' error
1495 MethodResolutionPhase errPhase = firstErroneousResolutionPhase();
1496 sym = access(methodResolutionCache.get(errPhase),
1497 pos, site, names.init, true, argtypes, typeargtypes);
1498 env.info.varArgs = errPhase.isVarargsRequired();
1499 }
1500 return sym;
1501 }
1503 /** Resolve constructor using diamond inference.
1504 * @param pos The position to use for error reporting.
1505 * @param env The environment current at the constructor invocation.
1506 * @param site The type of class for which a constructor is searched.
1507 * The scope of this class has been touched in attribution.
1508 * @param argtypes The types of the constructor invocation's value
1509 * arguments.
1510 * @param typeargtypes The types of the constructor invocation's type
1511 * arguments.
1512 */
1513 Symbol resolveDiamond(DiagnosticPosition pos,
1514 Env<AttrContext> env,
1515 Type site,
1516 List<Type> argtypes,
1517 List<Type> typeargtypes) {
1518 Symbol sym = startResolution();
1519 List<MethodResolutionPhase> steps = methodResolutionSteps;
1520 while (steps.nonEmpty() &&
1521 steps.head.isApplicable(boxingEnabled, varargsEnabled) &&
1522 sym.kind >= ERRONEOUS) {
1523 currentStep = steps.head;
1524 sym = resolveConstructor(pos, env, site, argtypes, typeargtypes,
1525 steps.head.isBoxingRequired(),
1526 env.info.varArgs = steps.head.isVarargsRequired());
1527 methodResolutionCache.put(steps.head, sym);
1528 steps = steps.tail;
1529 }
1530 if (sym.kind >= AMBIGUOUS) {
1531 final JCDiagnostic details = sym.kind == WRONG_MTH ?
1532 ((InapplicableSymbolError)sym).explanation :
1533 null;
1534 Symbol errSym = new ResolveError(WRONG_MTH, "diamond error") {
1535 @Override
1536 JCDiagnostic getDiagnostic(DiagnosticType dkind, DiagnosticPosition pos, Type site, Name name, List<Type> argtypes, List<Type> typeargtypes) {
1537 String key = details == null ?
1538 "cant.apply.diamond" :
1539 "cant.apply.diamond.1";
1540 return diags.create(dkind, log.currentSource(), pos, key, diags.fragment("diamond", site.tsym), details);
1541 }
1542 };
1543 MethodResolutionPhase errPhase = firstErroneousResolutionPhase();
1544 sym = access(errSym, pos, site, names.init, true, argtypes, typeargtypes);
1545 env.info.varArgs = errPhase.isVarargsRequired();
1546 }
1547 return sym;
1548 }
1550 /** Resolve constructor.
1551 * @param pos The position to use for error reporting.
1552 * @param env The environment current at the constructor invocation.
1553 * @param site The type of class for which a constructor is searched.
1554 * @param argtypes The types of the constructor invocation's value
1555 * arguments.
1556 * @param typeargtypes The types of the constructor invocation's type
1557 * arguments.
1558 * @param allowBoxing Allow boxing and varargs conversions.
1559 * @param useVarargs Box trailing arguments into an array for varargs.
1560 */
1561 Symbol resolveConstructor(DiagnosticPosition pos, Env<AttrContext> env,
1562 Type site, List<Type> argtypes,
1563 List<Type> typeargtypes,
1564 boolean allowBoxing,
1565 boolean useVarargs) {
1566 Symbol sym = findMethod(env, site,
1567 names.init, argtypes,
1568 typeargtypes, allowBoxing,
1569 useVarargs, false);
1570 if ((sym.flags() & DEPRECATED) != 0 &&
1571 (env.info.scope.owner.flags() & DEPRECATED) == 0 &&
1572 env.info.scope.owner.outermostClass() != sym.outermostClass())
1573 chk.warnDeprecated(pos, sym);
1574 return sym;
1575 }
1577 /** Resolve a constructor, throw a fatal error if not found.
1578 * @param pos The position to use for error reporting.
1579 * @param env The environment current at the method invocation.
1580 * @param site The type to be constructed.
1581 * @param argtypes The types of the invocation's value arguments.
1582 * @param typeargtypes The types of the invocation's type arguments.
1583 */
1584 public MethodSymbol resolveInternalConstructor(DiagnosticPosition pos, Env<AttrContext> env,
1585 Type site,
1586 List<Type> argtypes,
1587 List<Type> typeargtypes) {
1588 Symbol sym = resolveConstructor(
1589 pos, env, site, argtypes, typeargtypes);
1590 if (sym.kind == MTH) return (MethodSymbol)sym;
1591 else throw new FatalError(
1592 diags.fragment("fatal.err.cant.locate.ctor", site));
1593 }
1595 /** Resolve operator.
1596 * @param pos The position to use for error reporting.
1597 * @param optag The tag of the operation tree.
1598 * @param env The environment current at the operation.
1599 * @param argtypes The types of the operands.
1600 */
1601 Symbol resolveOperator(DiagnosticPosition pos, int optag,
1602 Env<AttrContext> env, List<Type> argtypes) {
1603 Name name = treeinfo.operatorName(optag);
1604 Symbol sym = findMethod(env, syms.predefClass.type, name, argtypes,
1605 null, false, false, true);
1606 if (boxingEnabled && sym.kind >= WRONG_MTHS)
1607 sym = findMethod(env, syms.predefClass.type, name, argtypes,
1608 null, true, false, true);
1609 return access(sym, pos, env.enclClass.sym.type, name,
1610 false, argtypes, null);
1611 }
1613 /** Resolve operator.
1614 * @param pos The position to use for error reporting.
1615 * @param optag The tag of the operation tree.
1616 * @param env The environment current at the operation.
1617 * @param arg The type of the operand.
1618 */
1619 Symbol resolveUnaryOperator(DiagnosticPosition pos, int optag, Env<AttrContext> env, Type arg) {
1620 return resolveOperator(pos, optag, env, List.of(arg));
1621 }
1623 /** Resolve binary operator.
1624 * @param pos The position to use for error reporting.
1625 * @param optag The tag of the operation tree.
1626 * @param env The environment current at the operation.
1627 * @param left The types of the left operand.
1628 * @param right The types of the right operand.
1629 */
1630 Symbol resolveBinaryOperator(DiagnosticPosition pos,
1631 int optag,
1632 Env<AttrContext> env,
1633 Type left,
1634 Type right) {
1635 return resolveOperator(pos, optag, env, List.of(left, right));
1636 }
1638 /**
1639 * Resolve `c.name' where name == this or name == super.
1640 * @param pos The position to use for error reporting.
1641 * @param env The environment current at the expression.
1642 * @param c The qualifier.
1643 * @param name The identifier's name.
1644 */
1645 Symbol resolveSelf(DiagnosticPosition pos,
1646 Env<AttrContext> env,
1647 TypeSymbol c,
1648 Name name) {
1649 Env<AttrContext> env1 = env;
1650 boolean staticOnly = false;
1651 while (env1.outer != null) {
1652 if (isStatic(env1)) staticOnly = true;
1653 if (env1.enclClass.sym == c) {
1654 Symbol sym = env1.info.scope.lookup(name).sym;
1655 if (sym != null) {
1656 if (staticOnly) sym = new StaticError(sym);
1657 return access(sym, pos, env.enclClass.sym.type,
1658 name, true);
1659 }
1660 }
1661 if ((env1.enclClass.sym.flags() & STATIC) != 0) staticOnly = true;
1662 env1 = env1.outer;
1663 }
1664 log.error(pos, "not.encl.class", c);
1665 return syms.errSymbol;
1666 }
1668 /**
1669 * Resolve `c.this' for an enclosing class c that contains the
1670 * named member.
1671 * @param pos The position to use for error reporting.
1672 * @param env The environment current at the expression.
1673 * @param member The member that must be contained in the result.
1674 */
1675 Symbol resolveSelfContaining(DiagnosticPosition pos,
1676 Env<AttrContext> env,
1677 Symbol member) {
1678 Name name = names._this;
1679 Env<AttrContext> env1 = env;
1680 boolean staticOnly = false;
1681 while (env1.outer != null) {
1682 if (isStatic(env1)) staticOnly = true;
1683 if (env1.enclClass.sym.isSubClass(member.owner, types) &&
1684 isAccessible(env, env1.enclClass.sym.type, member)) {
1685 Symbol sym = env1.info.scope.lookup(name).sym;
1686 if (sym != null) {
1687 if (staticOnly) sym = new StaticError(sym);
1688 return access(sym, pos, env.enclClass.sym.type,
1689 name, true);
1690 }
1691 }
1692 if ((env1.enclClass.sym.flags() & STATIC) != 0)
1693 staticOnly = true;
1694 env1 = env1.outer;
1695 }
1696 log.error(pos, "encl.class.required", member);
1697 return syms.errSymbol;
1698 }
1700 /**
1701 * Resolve an appropriate implicit this instance for t's container.
1702 * JLS2 8.8.5.1 and 15.9.2
1703 */
1704 Type resolveImplicitThis(DiagnosticPosition pos, Env<AttrContext> env, Type t) {
1705 Type thisType = (((t.tsym.owner.kind & (MTH|VAR)) != 0)
1706 ? resolveSelf(pos, env, t.getEnclosingType().tsym, names._this)
1707 : resolveSelfContaining(pos, env, t.tsym)).type;
1708 if (env.info.isSelfCall && thisType.tsym == env.enclClass.sym)
1709 log.error(pos, "cant.ref.before.ctor.called", "this");
1710 return thisType;
1711 }
1713 /* ***************************************************************************
1714 * ResolveError classes, indicating error situations when accessing symbols
1715 ****************************************************************************/
1717 public void logAccessError(Env<AttrContext> env, JCTree tree, Type type) {
1718 AccessError error = new AccessError(env, type.getEnclosingType(), type.tsym);
1719 logResolveError(error, tree.pos(), type.getEnclosingType(), null, null, null);
1720 }
1721 //where
1722 private void logResolveError(ResolveError error,
1723 DiagnosticPosition pos,
1724 Type site,
1725 Name name,
1726 List<Type> argtypes,
1727 List<Type> typeargtypes) {
1728 JCDiagnostic d = error.getDiagnostic(JCDiagnostic.DiagnosticType.ERROR,
1729 pos, site, name, argtypes, typeargtypes);
1730 if (d != null) {
1731 d.setFlag(DiagnosticFlag.RESOLVE_ERROR);
1732 log.report(d);
1733 }
1734 }
1736 private final LocalizedString noArgs = new LocalizedString("compiler.misc.no.args");
1738 public Object methodArguments(List<Type> argtypes) {
1739 return argtypes.isEmpty() ? noArgs : argtypes;
1740 }
1742 /**
1743 * Root class for resolution errors. Subclass of ResolveError
1744 * represent a different kinds of resolution error - as such they must
1745 * specify how they map into concrete compiler diagnostics.
1746 */
1747 private abstract class ResolveError extends Symbol {
1749 /** The name of the kind of error, for debugging only. */
1750 final String debugName;
1752 ResolveError(int kind, String debugName) {
1753 super(kind, 0, null, null, null);
1754 this.debugName = debugName;
1755 }
1757 @Override
1758 public <R, P> R accept(ElementVisitor<R, P> v, P p) {
1759 throw new AssertionError();
1760 }
1762 @Override
1763 public String toString() {
1764 return debugName;
1765 }
1767 @Override
1768 public boolean exists() {
1769 return false;
1770 }
1772 /**
1773 * Create an external representation for this erroneous symbol to be
1774 * used during attribution - by default this returns the symbol of a
1775 * brand new error type which stores the original type found
1776 * during resolution.
1777 *
1778 * @param name the name used during resolution
1779 * @param location the location from which the symbol is accessed
1780 */
1781 protected Symbol access(Name name, TypeSymbol location) {
1782 return types.createErrorType(name, location, syms.errSymbol.type).tsym;
1783 }
1785 /**
1786 * Create a diagnostic representing this resolution error.
1787 *
1788 * @param dkind The kind of the diagnostic to be created (e.g error).
1789 * @param pos The position to be used for error reporting.
1790 * @param site The original type from where the selection took place.
1791 * @param name The name of the symbol to be resolved.
1792 * @param argtypes The invocation's value arguments,
1793 * if we looked for a method.
1794 * @param typeargtypes The invocation's type arguments,
1795 * if we looked for a method.
1796 */
1797 abstract JCDiagnostic getDiagnostic(JCDiagnostic.DiagnosticType dkind,
1798 DiagnosticPosition pos,
1799 Type site,
1800 Name name,
1801 List<Type> argtypes,
1802 List<Type> typeargtypes);
1804 /**
1805 * A name designates an operator if it consists
1806 * of a non-empty sequence of operator symbols +-~!/*%&|^<>=
1807 */
1808 boolean isOperator(Name name) {
1809 int i = 0;
1810 while (i < name.getByteLength() &&
1811 "+-~!*/%&|^<>=".indexOf(name.getByteAt(i)) >= 0) i++;
1812 return i > 0 && i == name.getByteLength();
1813 }
1814 }
1816 /**
1817 * This class is the root class of all resolution errors caused by
1818 * an invalid symbol being found during resolution.
1819 */
1820 abstract class InvalidSymbolError extends ResolveError {
1822 /** The invalid symbol found during resolution */
1823 Symbol sym;
1825 InvalidSymbolError(int kind, Symbol sym, String debugName) {
1826 super(kind, debugName);
1827 this.sym = sym;
1828 }
1830 @Override
1831 public boolean exists() {
1832 return true;
1833 }
1835 @Override
1836 public String toString() {
1837 return super.toString() + " wrongSym=" + sym;
1838 }
1840 @Override
1841 public Symbol access(Name name, TypeSymbol location) {
1842 if (sym.kind >= AMBIGUOUS)
1843 return ((ResolveError)sym).access(name, location);
1844 else if ((sym.kind & ERRONEOUS) == 0 && (sym.kind & TYP) != 0)
1845 return types.createErrorType(name, location, sym.type).tsym;
1846 else
1847 return sym;
1848 }
1849 }
1851 /**
1852 * InvalidSymbolError error class indicating that a symbol matching a
1853 * given name does not exists in a given site.
1854 */
1855 class SymbolNotFoundError extends ResolveError {
1857 SymbolNotFoundError(int kind) {
1858 super(kind, "symbol not found error");
1859 }
1861 @Override
1862 JCDiagnostic getDiagnostic(JCDiagnostic.DiagnosticType dkind,
1863 DiagnosticPosition pos,
1864 Type site,
1865 Name name,
1866 List<Type> argtypes,
1867 List<Type> typeargtypes) {
1868 argtypes = argtypes == null ? List.<Type>nil() : argtypes;
1869 typeargtypes = typeargtypes == null ? List.<Type>nil() : typeargtypes;
1870 if (name == names.error)
1871 return null;
1873 if (isOperator(name)) {
1874 return diags.create(dkind, log.currentSource(), pos,
1875 "operator.cant.be.applied", name, argtypes);
1876 }
1877 boolean hasLocation = false;
1878 if (!site.tsym.name.isEmpty()) {
1879 if (site.tsym.kind == PCK && !site.tsym.exists()) {
1880 return diags.create(dkind, log.currentSource(), pos,
1881 "doesnt.exist", site.tsym);
1882 }
1883 hasLocation = true;
1884 }
1885 boolean isConstructor = kind == ABSENT_MTH &&
1886 name == names.table.names.init;
1887 KindName kindname = isConstructor ? KindName.CONSTRUCTOR : absentKind(kind);
1888 Name idname = isConstructor ? site.tsym.name : name;
1889 String errKey = getErrorKey(kindname, typeargtypes.nonEmpty(), hasLocation);
1890 if (hasLocation) {
1891 return diags.create(dkind, log.currentSource(), pos,
1892 errKey, kindname, idname, //symbol kindname, name
1893 typeargtypes, argtypes, //type parameters and arguments (if any)
1894 typeKindName(site), site); //location kindname, type
1895 }
1896 else {
1897 return diags.create(dkind, log.currentSource(), pos,
1898 errKey, kindname, idname, //symbol kindname, name
1899 typeargtypes, argtypes); //type parameters and arguments (if any)
1900 }
1901 }
1902 //where
1903 private String getErrorKey(KindName kindname, boolean hasTypeArgs, boolean hasLocation) {
1904 String key = "cant.resolve";
1905 String suffix = hasLocation ? ".location" : "";
1906 switch (kindname) {
1907 case METHOD:
1908 case CONSTRUCTOR: {
1909 suffix += ".args";
1910 suffix += hasTypeArgs ? ".params" : "";
1911 }
1912 }
1913 return key + suffix;
1914 }
1915 }
1917 /**
1918 * InvalidSymbolError error class indicating that a given symbol
1919 * (either a method, a constructor or an operand) is not applicable
1920 * given an actual arguments/type argument list.
1921 */
1922 class InapplicableSymbolError extends InvalidSymbolError {
1924 /** An auxiliary explanation set in case of instantiation errors. */
1925 JCDiagnostic explanation;
1927 InapplicableSymbolError(Symbol sym) {
1928 super(WRONG_MTH, sym, "inapplicable symbol error");
1929 }
1931 /** Update sym and explanation and return this.
1932 */
1933 InapplicableSymbolError setWrongSym(Symbol sym, JCDiagnostic explanation) {
1934 this.sym = sym;
1935 if (this.sym == sym && explanation != null)
1936 this.explanation = explanation; //update the details
1937 return this;
1938 }
1940 /** Update sym and return this.
1941 */
1942 InapplicableSymbolError setWrongSym(Symbol sym) {
1943 this.sym = sym;
1944 return this;
1945 }
1947 @Override
1948 public String toString() {
1949 return super.toString() + " explanation=" + explanation;
1950 }
1952 @Override
1953 JCDiagnostic getDiagnostic(JCDiagnostic.DiagnosticType dkind,
1954 DiagnosticPosition pos,
1955 Type site,
1956 Name name,
1957 List<Type> argtypes,
1958 List<Type> typeargtypes) {
1959 if (name == names.error)
1960 return null;
1962 if (isOperator(name)) {
1963 return diags.create(dkind, log.currentSource(),
1964 pos, "operator.cant.be.applied", name, argtypes);
1965 }
1966 else {
1967 Symbol ws = sym.asMemberOf(site, types);
1968 return diags.create(dkind, log.currentSource(), pos,
1969 "cant.apply.symbol" + (explanation != null ? ".1" : ""),
1970 kindName(ws),
1971 ws.name == names.init ? ws.owner.name : ws.name,
1972 methodArguments(ws.type.getParameterTypes()),
1973 methodArguments(argtypes),
1974 kindName(ws.owner),
1975 ws.owner.type,
1976 explanation);
1977 }
1978 }
1980 void clear() {
1981 explanation = null;
1982 }
1984 @Override
1985 public Symbol access(Name name, TypeSymbol location) {
1986 return types.createErrorType(name, location, syms.errSymbol.type).tsym;
1987 }
1988 }
1990 /**
1991 * ResolveError error class indicating that a set of symbols
1992 * (either methods, constructors or operands) is not applicable
1993 * given an actual arguments/type argument list.
1994 */
1995 class InapplicableSymbolsError extends ResolveError {
1997 private List<Candidate> candidates = List.nil();
1999 InapplicableSymbolsError(Symbol sym) {
2000 super(WRONG_MTHS, "inapplicable symbols");
2001 }
2003 @Override
2004 JCDiagnostic getDiagnostic(JCDiagnostic.DiagnosticType dkind,
2005 DiagnosticPosition pos,
2006 Type site,
2007 Name name,
2008 List<Type> argtypes,
2009 List<Type> typeargtypes) {
2010 if (candidates.nonEmpty()) {
2011 JCDiagnostic err = diags.create(dkind,
2012 log.currentSource(),
2013 pos,
2014 "cant.apply.symbols",
2015 name == names.init ? KindName.CONSTRUCTOR : absentKind(kind),
2016 getName(),
2017 argtypes);
2018 return new JCDiagnostic.MultilineDiagnostic(err, candidateDetails(site));
2019 } else {
2020 return new SymbolNotFoundError(ABSENT_MTH).getDiagnostic(dkind, pos,
2021 site, name, argtypes, typeargtypes);
2022 }
2023 }
2025 //where
2026 List<JCDiagnostic> candidateDetails(Type site) {
2027 List<JCDiagnostic> details = List.nil();
2028 for (Candidate c : candidates)
2029 details = details.prepend(c.getDiagnostic(site));
2030 return details.reverse();
2031 }
2033 Symbol addCandidate(MethodResolutionPhase currentStep, Symbol sym, JCDiagnostic details) {
2034 Candidate c = new Candidate(currentStep, sym, details);
2035 if (c.isValid() && !candidates.contains(c))
2036 candidates = candidates.append(c);
2037 return this;
2038 }
2040 void clear() {
2041 candidates = List.nil();
2042 }
2044 private Name getName() {
2045 Symbol sym = candidates.head.sym;
2046 return sym.name == names.init ?
2047 sym.owner.name :
2048 sym.name;
2049 }
2051 private class Candidate {
2053 final MethodResolutionPhase step;
2054 final Symbol sym;
2055 final JCDiagnostic details;
2057 private Candidate(MethodResolutionPhase step, Symbol sym, JCDiagnostic details) {
2058 this.step = step;
2059 this.sym = sym;
2060 this.details = details;
2061 }
2063 JCDiagnostic getDiagnostic(Type site) {
2064 return diags.fragment("inapplicable.method",
2065 Kinds.kindName(sym),
2066 sym.location(site, types),
2067 sym.asMemberOf(site, types),
2068 details);
2069 }
2071 @Override
2072 public boolean equals(Object o) {
2073 if (o instanceof Candidate) {
2074 Symbol s1 = this.sym;
2075 Symbol s2 = ((Candidate)o).sym;
2076 if ((s1 != s2 &&
2077 (s1.overrides(s2, s1.owner.type.tsym, types, false) ||
2078 (s2.overrides(s1, s2.owner.type.tsym, types, false)))) ||
2079 ((s1.isConstructor() || s2.isConstructor()) && s1.owner != s2.owner))
2080 return true;
2081 }
2082 return false;
2083 }
2085 boolean isValid() {
2086 return (((sym.flags() & VARARGS) != 0 && step == VARARITY) ||
2087 (sym.flags() & VARARGS) == 0 && step == (boxingEnabled ? BOX : BASIC));
2088 }
2089 }
2090 }
2092 /**
2093 * An InvalidSymbolError error class indicating that a symbol is not
2094 * accessible from a given site
2095 */
2096 class AccessError extends InvalidSymbolError {
2098 private Env<AttrContext> env;
2099 private Type site;
2101 AccessError(Symbol sym) {
2102 this(null, null, sym);
2103 }
2105 AccessError(Env<AttrContext> env, Type site, Symbol sym) {
2106 super(HIDDEN, sym, "access error");
2107 this.env = env;
2108 this.site = site;
2109 if (debugResolve)
2110 log.error("proc.messager", sym + " @ " + site + " is inaccessible.");
2111 }
2113 @Override
2114 public boolean exists() {
2115 return false;
2116 }
2118 @Override
2119 JCDiagnostic getDiagnostic(JCDiagnostic.DiagnosticType dkind,
2120 DiagnosticPosition pos,
2121 Type site,
2122 Name name,
2123 List<Type> argtypes,
2124 List<Type> typeargtypes) {
2125 if (sym.owner.type.tag == ERROR)
2126 return null;
2128 if (sym.name == names.init && sym.owner != site.tsym) {
2129 return new SymbolNotFoundError(ABSENT_MTH).getDiagnostic(dkind,
2130 pos, site, name, argtypes, typeargtypes);
2131 }
2132 else if ((sym.flags() & PUBLIC) != 0
2133 || (env != null && this.site != null
2134 && !isAccessible(env, this.site))) {
2135 return diags.create(dkind, log.currentSource(),
2136 pos, "not.def.access.class.intf.cant.access",
2137 sym, sym.location());
2138 }
2139 else if ((sym.flags() & (PRIVATE | PROTECTED)) != 0) {
2140 return diags.create(dkind, log.currentSource(),
2141 pos, "report.access", sym,
2142 asFlagSet(sym.flags() & (PRIVATE | PROTECTED)),
2143 sym.location());
2144 }
2145 else {
2146 return diags.create(dkind, log.currentSource(),
2147 pos, "not.def.public.cant.access", sym, sym.location());
2148 }
2149 }
2150 }
2152 /**
2153 * InvalidSymbolError error class indicating that an instance member
2154 * has erroneously been accessed from a static context.
2155 */
2156 class StaticError extends InvalidSymbolError {
2158 StaticError(Symbol sym) {
2159 super(STATICERR, sym, "static error");
2160 }
2162 @Override
2163 JCDiagnostic getDiagnostic(JCDiagnostic.DiagnosticType dkind,
2164 DiagnosticPosition pos,
2165 Type site,
2166 Name name,
2167 List<Type> argtypes,
2168 List<Type> typeargtypes) {
2169 Symbol errSym = ((sym.kind == TYP && sym.type.tag == CLASS)
2170 ? types.erasure(sym.type).tsym
2171 : sym);
2172 return diags.create(dkind, log.currentSource(), pos,
2173 "non-static.cant.be.ref", kindName(sym), errSym);
2174 }
2175 }
2177 /**
2178 * InvalidSymbolError error class indicating that a pair of symbols
2179 * (either methods, constructors or operands) are ambiguous
2180 * given an actual arguments/type argument list.
2181 */
2182 class AmbiguityError extends InvalidSymbolError {
2184 /** The other maximally specific symbol */
2185 Symbol sym2;
2187 AmbiguityError(Symbol sym1, Symbol sym2) {
2188 super(AMBIGUOUS, sym1, "ambiguity error");
2189 this.sym2 = sym2;
2190 }
2192 @Override
2193 JCDiagnostic getDiagnostic(JCDiagnostic.DiagnosticType dkind,
2194 DiagnosticPosition pos,
2195 Type site,
2196 Name name,
2197 List<Type> argtypes,
2198 List<Type> typeargtypes) {
2199 AmbiguityError pair = this;
2200 while (true) {
2201 if (pair.sym.kind == AMBIGUOUS)
2202 pair = (AmbiguityError)pair.sym;
2203 else if (pair.sym2.kind == AMBIGUOUS)
2204 pair = (AmbiguityError)pair.sym2;
2205 else break;
2206 }
2207 Name sname = pair.sym.name;
2208 if (sname == names.init) sname = pair.sym.owner.name;
2209 return diags.create(dkind, log.currentSource(),
2210 pos, "ref.ambiguous", sname,
2211 kindName(pair.sym),
2212 pair.sym,
2213 pair.sym.location(site, types),
2214 kindName(pair.sym2),
2215 pair.sym2,
2216 pair.sym2.location(site, types));
2217 }
2218 }
2220 enum MethodResolutionPhase {
2221 BASIC(false, false),
2222 BOX(true, false),
2223 VARARITY(true, true);
2225 boolean isBoxingRequired;
2226 boolean isVarargsRequired;
2228 MethodResolutionPhase(boolean isBoxingRequired, boolean isVarargsRequired) {
2229 this.isBoxingRequired = isBoxingRequired;
2230 this.isVarargsRequired = isVarargsRequired;
2231 }
2233 public boolean isBoxingRequired() {
2234 return isBoxingRequired;
2235 }
2237 public boolean isVarargsRequired() {
2238 return isVarargsRequired;
2239 }
2241 public boolean isApplicable(boolean boxingEnabled, boolean varargsEnabled) {
2242 return (varargsEnabled || !isVarargsRequired) &&
2243 (boxingEnabled || !isBoxingRequired);
2244 }
2245 }
2247 private Map<MethodResolutionPhase, Symbol> methodResolutionCache =
2248 new HashMap<MethodResolutionPhase, Symbol>(MethodResolutionPhase.values().length);
2250 final List<MethodResolutionPhase> methodResolutionSteps = List.of(BASIC, BOX, VARARITY);
2252 private MethodResolutionPhase currentStep = null;
2254 private MethodResolutionPhase firstErroneousResolutionPhase() {
2255 MethodResolutionPhase bestSoFar = BASIC;
2256 Symbol sym = methodNotFound;
2257 List<MethodResolutionPhase> steps = methodResolutionSteps;
2258 while (steps.nonEmpty() &&
2259 steps.head.isApplicable(boxingEnabled, varargsEnabled) &&
2260 sym.kind >= WRONG_MTHS) {
2261 sym = methodResolutionCache.get(steps.head);
2262 bestSoFar = steps.head;
2263 steps = steps.tail;
2264 }
2265 return bestSoFar;
2266 }
2267 }