Mercurial > jdk8-mips64-public > langtools / file revision
src/share/classes/com/sun/tools/javac/comp/Resolve.java@5e89c4ca637c
src/share/classes/com/sun/tools/javac/comp/Resolve.java
Fri, 29 Aug 2008 11:10:12 -0700
- author
- jjg
- date
- Fri, 29 Aug 2008 11:10:12 -0700
- changeset 104
- 5e89c4ca637c
- parent 89
- b6d5f53b3b29
- child 110
- 91eea580fbe9
- permissions
- -rw-r--r--
6597471: unused imports in javax.tools.JavaCompiler
6597531: unused imports and unused private const. in com.sun.tools.javac.Server.java
Reviewed-by: mcimadamore
Contributed-by: davide.angelocola@gmail.com
1 /*
2 * Copyright 1999-2008 Sun Microsystems, Inc. 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. Sun designates this
8 * particular file as subject to the "Classpath" exception as provided
9 * by Sun 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 Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,
22 * CA 95054 USA or visit www.sun.com if you need additional information or
23 * have any 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.*;
34 import com.sun.tools.javac.code.Type.*;
35 import com.sun.tools.javac.code.Symbol.*;
36 import com.sun.tools.javac.tree.JCTree.*;
38 import static com.sun.tools.javac.code.Flags.*;
39 import static com.sun.tools.javac.code.Kinds.*;
40 import static com.sun.tools.javac.code.TypeTags.*;
41 import javax.lang.model.element.ElementVisitor;
43 /** Helper class for name resolution, used mostly by the attribution phase.
44 *
45 * <p><b>This is NOT part of any API supported by Sun Microsystems. If
46 * you write code that depends on this, you do so at your own risk.
47 * This code and its internal interfaces are subject to change or
48 * deletion without notice.</b>
49 */
50 public class Resolve {
51 protected static final Context.Key<Resolve> resolveKey =
52 new Context.Key<Resolve>();
54 Name.Table names;
55 Log log;
56 Symtab syms;
57 Check chk;
58 Infer infer;
59 ClassReader reader;
60 TreeInfo treeinfo;
61 Types types;
62 JCDiagnostic.Factory diags;
63 public final boolean boxingEnabled; // = source.allowBoxing();
64 public final boolean varargsEnabled; // = source.allowVarargs();
65 private final boolean debugResolve;
67 public static Resolve instance(Context context) {
68 Resolve instance = context.get(resolveKey);
69 if (instance == null)
70 instance = new Resolve(context);
71 return instance;
72 }
74 protected Resolve(Context context) {
75 context.put(resolveKey, this);
76 syms = Symtab.instance(context);
78 varNotFound = new
79 ResolveError(ABSENT_VAR, syms.errSymbol, "variable not found");
80 wrongMethod = new
81 ResolveError(WRONG_MTH, syms.errSymbol, "method not found");
82 wrongMethods = new
83 ResolveError(WRONG_MTHS, syms.errSymbol, "wrong methods");
84 methodNotFound = new
85 ResolveError(ABSENT_MTH, syms.errSymbol, "method not found");
86 typeNotFound = new
87 ResolveError(ABSENT_TYP, syms.errSymbol, "type not found");
89 names = Name.Table.instance(context);
90 log = Log.instance(context);
91 chk = Check.instance(context);
92 infer = Infer.instance(context);
93 reader = ClassReader.instance(context);
94 treeinfo = TreeInfo.instance(context);
95 types = Types.instance(context);
96 diags = JCDiagnostic.Factory.instance(context);
97 Source source = Source.instance(context);
98 boxingEnabled = source.allowBoxing();
99 varargsEnabled = source.allowVarargs();
100 Options options = Options.instance(context);
101 debugResolve = options.get("debugresolve") != null;
102 }
104 /** error symbols, which are returned when resolution fails
105 */
106 final ResolveError varNotFound;
107 final ResolveError wrongMethod;
108 final ResolveError wrongMethods;
109 final ResolveError methodNotFound;
110 final ResolveError typeNotFound;
112 /* ************************************************************************
113 * Identifier resolution
114 *************************************************************************/
116 /** An environment is "static" if its static level is greater than
117 * the one of its outer environment
118 */
119 static boolean isStatic(Env<AttrContext> env) {
120 return env.info.staticLevel > env.outer.info.staticLevel;
121 }
123 /** An environment is an "initializer" if it is a constructor or
124 * an instance initializer.
125 */
126 static boolean isInitializer(Env<AttrContext> env) {
127 Symbol owner = env.info.scope.owner;
128 return owner.isConstructor() ||
129 owner.owner.kind == TYP &&
130 (owner.kind == VAR ||
131 owner.kind == MTH && (owner.flags() & BLOCK) != 0) &&
132 (owner.flags() & STATIC) == 0;
133 }
135 /** Is class accessible in given evironment?
136 * @param env The current environment.
137 * @param c The class whose accessibility is checked.
138 */
139 public boolean isAccessible(Env<AttrContext> env, TypeSymbol c) {
140 switch ((short)(c.flags() & AccessFlags)) {
141 case PRIVATE:
142 return
143 env.enclClass.sym.outermostClass() ==
144 c.owner.outermostClass();
145 case 0:
146 return
147 env.toplevel.packge == c.owner // fast special case
148 ||
149 env.toplevel.packge == c.packge()
150 ||
151 // Hack: this case is added since synthesized default constructors
152 // of anonymous classes should be allowed to access
153 // classes which would be inaccessible otherwise.
154 env.enclMethod != null &&
155 (env.enclMethod.mods.flags & ANONCONSTR) != 0;
156 default: // error recovery
157 case PUBLIC:
158 return true;
159 case PROTECTED:
160 return
161 env.toplevel.packge == c.owner // fast special case
162 ||
163 env.toplevel.packge == c.packge()
164 ||
165 isInnerSubClass(env.enclClass.sym, c.owner);
166 }
167 }
168 //where
169 /** Is given class a subclass of given base class, or an inner class
170 * of a subclass?
171 * Return null if no such class exists.
172 * @param c The class which is the subclass or is contained in it.
173 * @param base The base class
174 */
175 private boolean isInnerSubClass(ClassSymbol c, Symbol base) {
176 while (c != null && !c.isSubClass(base, types)) {
177 c = c.owner.enclClass();
178 }
179 return c != null;
180 }
182 boolean isAccessible(Env<AttrContext> env, Type t) {
183 return (t.tag == ARRAY)
184 ? isAccessible(env, types.elemtype(t))
185 : isAccessible(env, t.tsym);
186 }
188 /** Is symbol accessible as a member of given type in given evironment?
189 * @param env The current environment.
190 * @param site The type of which the tested symbol is regarded
191 * as a member.
192 * @param sym The symbol.
193 */
194 public boolean isAccessible(Env<AttrContext> env, Type site, Symbol sym) {
195 if (sym.name == names.init && sym.owner != site.tsym) return false;
196 ClassSymbol sub;
197 switch ((short)(sym.flags() & AccessFlags)) {
198 case PRIVATE:
199 return
200 (env.enclClass.sym == sym.owner // fast special case
201 ||
202 env.enclClass.sym.outermostClass() ==
203 sym.owner.outermostClass())
204 &&
205 sym.isInheritedIn(site.tsym, types);
206 case 0:
207 return
208 (env.toplevel.packge == sym.owner.owner // fast special case
209 ||
210 env.toplevel.packge == sym.packge())
211 &&
212 isAccessible(env, site)
213 &&
214 sym.isInheritedIn(site.tsym, types);
215 case PROTECTED:
216 return
217 (env.toplevel.packge == sym.owner.owner // fast special case
218 ||
219 env.toplevel.packge == sym.packge()
220 ||
221 isProtectedAccessible(sym, env.enclClass.sym, site)
222 ||
223 // OK to select instance method or field from 'super' or type name
224 // (but type names should be disallowed elsewhere!)
225 env.info.selectSuper && (sym.flags() & STATIC) == 0 && sym.kind != TYP)
226 &&
227 isAccessible(env, site)
228 &&
229 // `sym' is accessible only if not overridden by
230 // another symbol which is a member of `site'
231 // (because, if it is overridden, `sym' is not strictly
232 // speaking a member of `site'.)
233 (sym.kind != MTH || sym.isConstructor() || sym.isStatic() ||
234 ((MethodSymbol)sym).implementation(site.tsym, types, true) == sym);
235 default: // this case includes erroneous combinations as well
236 return isAccessible(env, site);
237 }
238 }
239 //where
240 /** Is given protected symbol accessible if it is selected from given site
241 * and the selection takes place in given class?
242 * @param sym The symbol with protected access
243 * @param c The class where the access takes place
244 * @site The type of the qualifier
245 */
246 private
247 boolean isProtectedAccessible(Symbol sym, ClassSymbol c, Type site) {
248 while (c != null &&
249 !(c.isSubClass(sym.owner, types) &&
250 (c.flags() & INTERFACE) == 0 &&
251 // In JLS 2e 6.6.2.1, the subclass restriction applies
252 // only to instance fields and methods -- types are excluded
253 // regardless of whether they are declared 'static' or not.
254 ((sym.flags() & STATIC) != 0 || sym.kind == TYP || site.tsym.isSubClass(c, types))))
255 c = c.owner.enclClass();
256 return c != null;
257 }
259 /** Try to instantiate the type of a method so that it fits
260 * given type arguments and argument types. If succesful, return
261 * the method's instantiated type, else return null.
262 * The instantiation will take into account an additional leading
263 * formal parameter if the method is an instance method seen as a member
264 * of un underdetermined site In this case, we treat site as an additional
265 * parameter and the parameters of the class containing the method as
266 * additional type variables that get instantiated.
267 *
268 * @param env The current environment
269 * @param site The type of which the method is a member.
270 * @param m The method symbol.
271 * @param argtypes The invocation's given value arguments.
272 * @param typeargtypes The invocation's given type arguments.
273 * @param allowBoxing Allow boxing conversions of arguments.
274 * @param useVarargs Box trailing arguments into an array for varargs.
275 */
276 Type rawInstantiate(Env<AttrContext> env,
277 Type site,
278 Symbol m,
279 List<Type> argtypes,
280 List<Type> typeargtypes,
281 boolean allowBoxing,
282 boolean useVarargs,
283 Warner warn)
284 throws Infer.NoInstanceException {
285 if (useVarargs && (m.flags() & VARARGS) == 0) return null;
286 Type mt = types.memberType(site, m);
288 // tvars is the list of formal type variables for which type arguments
289 // need to inferred.
290 List<Type> tvars = env.info.tvars;
291 if (typeargtypes == null) typeargtypes = List.nil();
292 if (mt.tag != FORALL && typeargtypes.nonEmpty()) {
293 // This is not a polymorphic method, but typeargs are supplied
294 // which is fine, see JLS3 15.12.2.1
295 } else if (mt.tag == FORALL && typeargtypes.nonEmpty()) {
296 ForAll pmt = (ForAll) mt;
297 if (typeargtypes.length() != pmt.tvars.length())
298 return null;
299 // Check type arguments are within bounds
300 List<Type> formals = pmt.tvars;
301 List<Type> actuals = typeargtypes;
302 while (formals.nonEmpty() && actuals.nonEmpty()) {
303 List<Type> bounds = types.subst(types.getBounds((TypeVar)formals.head),
304 pmt.tvars, typeargtypes);
305 for (; bounds.nonEmpty(); bounds = bounds.tail)
306 if (!types.isSubtypeUnchecked(actuals.head, bounds.head, warn))
307 return null;
308 formals = formals.tail;
309 actuals = actuals.tail;
310 }
311 mt = types.subst(pmt.qtype, pmt.tvars, typeargtypes);
312 } else if (mt.tag == FORALL) {
313 ForAll pmt = (ForAll) mt;
314 List<Type> tvars1 = types.newInstances(pmt.tvars);
315 tvars = tvars.appendList(tvars1);
316 mt = types.subst(pmt.qtype, pmt.tvars, tvars1);
317 }
319 // find out whether we need to go the slow route via infer
320 boolean instNeeded = tvars.tail != null/*inlined: tvars.nonEmpty()*/;
321 for (List<Type> l = argtypes;
322 l.tail != null/*inlined: l.nonEmpty()*/ && !instNeeded;
323 l = l.tail) {
324 if (l.head.tag == FORALL) instNeeded = true;
325 }
327 if (instNeeded)
328 return
329 infer.instantiateMethod(tvars,
330 (MethodType)mt,
331 argtypes,
332 allowBoxing,
333 useVarargs,
334 warn);
335 return
336 argumentsAcceptable(argtypes, mt.getParameterTypes(),
337 allowBoxing, useVarargs, warn)
338 ? mt
339 : null;
340 }
342 /** Same but returns null instead throwing a NoInstanceException
343 */
344 Type instantiate(Env<AttrContext> env,
345 Type site,
346 Symbol m,
347 List<Type> argtypes,
348 List<Type> typeargtypes,
349 boolean allowBoxing,
350 boolean useVarargs,
351 Warner warn) {
352 try {
353 return rawInstantiate(env, site, m, argtypes, typeargtypes,
354 allowBoxing, useVarargs, warn);
355 } catch (Infer.NoInstanceException ex) {
356 return null;
357 }
358 }
360 /** Check if a parameter list accepts a list of args.
361 */
362 boolean argumentsAcceptable(List<Type> argtypes,
363 List<Type> formals,
364 boolean allowBoxing,
365 boolean useVarargs,
366 Warner warn) {
367 Type varargsFormal = useVarargs ? formals.last() : null;
368 while (argtypes.nonEmpty() && formals.head != varargsFormal) {
369 boolean works = allowBoxing
370 ? types.isConvertible(argtypes.head, formals.head, warn)
371 : types.isSubtypeUnchecked(argtypes.head, formals.head, warn);
372 if (!works) return false;
373 argtypes = argtypes.tail;
374 formals = formals.tail;
375 }
376 if (formals.head != varargsFormal) return false; // not enough args
377 if (!useVarargs)
378 return argtypes.isEmpty();
379 Type elt = types.elemtype(varargsFormal);
380 while (argtypes.nonEmpty()) {
381 if (!types.isConvertible(argtypes.head, elt, warn))
382 return false;
383 argtypes = argtypes.tail;
384 }
385 return true;
386 }
388 /* ***************************************************************************
389 * Symbol lookup
390 * the following naming conventions for arguments are used
391 *
392 * env is the environment where the symbol was mentioned
393 * site is the type of which the symbol is a member
394 * name is the symbol's name
395 * if no arguments are given
396 * argtypes are the value arguments, if we search for a method
397 *
398 * If no symbol was found, a ResolveError detailing the problem is returned.
399 ****************************************************************************/
401 /** Find field. Synthetic fields are always skipped.
402 * @param env The current environment.
403 * @param site The original type from where the selection takes place.
404 * @param name The name of the field.
405 * @param c The class to search for the field. This is always
406 * a superclass or implemented interface of site's class.
407 */
408 Symbol findField(Env<AttrContext> env,
409 Type site,
410 Name name,
411 TypeSymbol c) {
412 while (c.type.tag == TYPEVAR)
413 c = c.type.getUpperBound().tsym;
414 Symbol bestSoFar = varNotFound;
415 Symbol sym;
416 Scope.Entry e = c.members().lookup(name);
417 while (e.scope != null) {
418 if (e.sym.kind == VAR && (e.sym.flags_field & SYNTHETIC) == 0) {
419 return isAccessible(env, site, e.sym)
420 ? e.sym : new AccessError(env, site, e.sym);
421 }
422 e = e.next();
423 }
424 Type st = types.supertype(c.type);
425 if (st != null && (st.tag == CLASS || st.tag == TYPEVAR)) {
426 sym = findField(env, site, name, st.tsym);
427 if (sym.kind < bestSoFar.kind) bestSoFar = sym;
428 }
429 for (List<Type> l = types.interfaces(c.type);
430 bestSoFar.kind != AMBIGUOUS && l.nonEmpty();
431 l = l.tail) {
432 sym = findField(env, site, name, l.head.tsym);
433 if (bestSoFar.kind < AMBIGUOUS && sym.kind < AMBIGUOUS &&
434 sym.owner != bestSoFar.owner)
435 bestSoFar = new AmbiguityError(bestSoFar, sym);
436 else if (sym.kind < bestSoFar.kind)
437 bestSoFar = sym;
438 }
439 return bestSoFar;
440 }
442 /** Resolve a field identifier, throw a fatal error if not found.
443 * @param pos The position to use for error reporting.
444 * @param env The environment current at the method invocation.
445 * @param site The type of the qualifying expression, in which
446 * identifier is searched.
447 * @param name The identifier's name.
448 */
449 public VarSymbol resolveInternalField(DiagnosticPosition pos, Env<AttrContext> env,
450 Type site, Name name) {
451 Symbol sym = findField(env, site, name, site.tsym);
452 if (sym.kind == VAR) return (VarSymbol)sym;
453 else throw new FatalError(
454 diags.fragment("fatal.err.cant.locate.field",
455 name));
456 }
458 /** Find unqualified variable or field with given name.
459 * Synthetic fields always skipped.
460 * @param env The current environment.
461 * @param name The name of the variable or field.
462 */
463 Symbol findVar(Env<AttrContext> env, Name name) {
464 Symbol bestSoFar = varNotFound;
465 Symbol sym;
466 Env<AttrContext> env1 = env;
467 boolean staticOnly = false;
468 while (env1.outer != null) {
469 if (isStatic(env1)) staticOnly = true;
470 Scope.Entry e = env1.info.scope.lookup(name);
471 while (e.scope != null &&
472 (e.sym.kind != VAR ||
473 (e.sym.flags_field & SYNTHETIC) != 0))
474 e = e.next();
475 sym = (e.scope != null)
476 ? e.sym
477 : findField(
478 env1, env1.enclClass.sym.type, name, env1.enclClass.sym);
479 if (sym.exists()) {
480 if (staticOnly &&
481 sym.kind == VAR &&
482 sym.owner.kind == TYP &&
483 (sym.flags() & STATIC) == 0)
484 return new StaticError(sym);
485 else
486 return sym;
487 } else if (sym.kind < bestSoFar.kind) {
488 bestSoFar = sym;
489 }
491 if ((env1.enclClass.sym.flags() & STATIC) != 0) staticOnly = true;
492 env1 = env1.outer;
493 }
495 sym = findField(env, syms.predefClass.type, name, syms.predefClass);
496 if (sym.exists())
497 return sym;
498 if (bestSoFar.exists())
499 return bestSoFar;
501 Scope.Entry e = env.toplevel.namedImportScope.lookup(name);
502 for (; e.scope != null; e = e.next()) {
503 sym = e.sym;
504 Type origin = e.getOrigin().owner.type;
505 if (sym.kind == VAR) {
506 if (e.sym.owner.type != origin)
507 sym = sym.clone(e.getOrigin().owner);
508 return isAccessible(env, origin, sym)
509 ? sym : new AccessError(env, origin, sym);
510 }
511 }
513 Symbol origin = null;
514 e = env.toplevel.starImportScope.lookup(name);
515 for (; e.scope != null; e = e.next()) {
516 sym = e.sym;
517 if (sym.kind != VAR)
518 continue;
519 // invariant: sym.kind == VAR
520 if (bestSoFar.kind < AMBIGUOUS && sym.owner != bestSoFar.owner)
521 return new AmbiguityError(bestSoFar, sym);
522 else if (bestSoFar.kind >= VAR) {
523 origin = e.getOrigin().owner;
524 bestSoFar = isAccessible(env, origin.type, sym)
525 ? sym : new AccessError(env, origin.type, sym);
526 }
527 }
528 if (bestSoFar.kind == VAR && bestSoFar.owner.type != origin.type)
529 return bestSoFar.clone(origin);
530 else
531 return bestSoFar;
532 }
534 Warner noteWarner = new Warner();
536 /** Select the best method for a call site among two choices.
537 * @param env The current environment.
538 * @param site The original type from where the
539 * selection takes place.
540 * @param argtypes The invocation's value arguments,
541 * @param typeargtypes The invocation's type arguments,
542 * @param sym Proposed new best match.
543 * @param bestSoFar Previously found best match.
544 * @param allowBoxing Allow boxing conversions of arguments.
545 * @param useVarargs Box trailing arguments into an array for varargs.
546 */
547 Symbol selectBest(Env<AttrContext> env,
548 Type site,
549 List<Type> argtypes,
550 List<Type> typeargtypes,
551 Symbol sym,
552 Symbol bestSoFar,
553 boolean allowBoxing,
554 boolean useVarargs,
555 boolean operator) {
556 if (sym.kind == ERR) return bestSoFar;
557 if (!sym.isInheritedIn(site.tsym, types)) return bestSoFar;
558 assert sym.kind < AMBIGUOUS;
559 try {
560 if (rawInstantiate(env, site, sym, argtypes, typeargtypes,
561 allowBoxing, useVarargs, Warner.noWarnings) == null) {
562 // inapplicable
563 switch (bestSoFar.kind) {
564 case ABSENT_MTH: return wrongMethod.setWrongSym(sym);
565 case WRONG_MTH: return wrongMethods;
566 default: return bestSoFar;
567 }
568 }
569 } catch (Infer.NoInstanceException ex) {
570 switch (bestSoFar.kind) {
571 case ABSENT_MTH:
572 return wrongMethod.setWrongSym(sym, ex.getDiagnostic());
573 case WRONG_MTH:
574 return wrongMethods;
575 default:
576 return bestSoFar;
577 }
578 }
579 if (!isAccessible(env, site, sym)) {
580 return (bestSoFar.kind == ABSENT_MTH)
581 ? new AccessError(env, site, sym)
582 : bestSoFar;
583 }
584 return (bestSoFar.kind > AMBIGUOUS)
585 ? sym
586 : mostSpecific(sym, bestSoFar, env, site,
587 allowBoxing && operator, useVarargs);
588 }
590 /* Return the most specific of the two methods for a call,
591 * given that both are accessible and applicable.
592 * @param m1 A new candidate for most specific.
593 * @param m2 The previous most specific candidate.
594 * @param env The current environment.
595 * @param site The original type from where the selection
596 * takes place.
597 * @param allowBoxing Allow boxing conversions of arguments.
598 * @param useVarargs Box trailing arguments into an array for varargs.
599 */
600 Symbol mostSpecific(Symbol m1,
601 Symbol m2,
602 Env<AttrContext> env,
603 Type site,
604 boolean allowBoxing,
605 boolean useVarargs) {
606 switch (m2.kind) {
607 case MTH:
608 if (m1 == m2) return m1;
609 Type mt1 = types.memberType(site, m1);
610 noteWarner.unchecked = false;
611 boolean m1SignatureMoreSpecific =
612 (instantiate(env, site, m2, types.lowerBoundArgtypes(mt1), null,
613 allowBoxing, false, noteWarner) != null ||
614 useVarargs && instantiate(env, site, m2, types.lowerBoundArgtypes(mt1), null,
615 allowBoxing, true, noteWarner) != null) &&
616 !noteWarner.unchecked;
617 Type mt2 = types.memberType(site, m2);
618 noteWarner.unchecked = false;
619 boolean m2SignatureMoreSpecific =
620 (instantiate(env, site, m1, types.lowerBoundArgtypes(mt2), null,
621 allowBoxing, false, noteWarner) != null ||
622 useVarargs && instantiate(env, site, m1, types.lowerBoundArgtypes(mt2), null,
623 allowBoxing, true, noteWarner) != null) &&
624 !noteWarner.unchecked;
625 if (m1SignatureMoreSpecific && m2SignatureMoreSpecific) {
626 if (!types.overrideEquivalent(mt1, mt2))
627 return new AmbiguityError(m1, m2);
628 // same signature; select (a) the non-bridge method, or
629 // (b) the one that overrides the other, or (c) the concrete
630 // one, or (d) merge both abstract signatures
631 if ((m1.flags() & BRIDGE) != (m2.flags() & BRIDGE)) {
632 return ((m1.flags() & BRIDGE) != 0) ? m2 : m1;
633 }
634 // if one overrides or hides the other, use it
635 TypeSymbol m1Owner = (TypeSymbol)m1.owner;
636 TypeSymbol m2Owner = (TypeSymbol)m2.owner;
637 if (types.asSuper(m1Owner.type, m2Owner) != null &&
638 ((m1.owner.flags_field & INTERFACE) == 0 ||
639 (m2.owner.flags_field & INTERFACE) != 0) &&
640 m1.overrides(m2, m1Owner, types, false))
641 return m1;
642 if (types.asSuper(m2Owner.type, m1Owner) != null &&
643 ((m2.owner.flags_field & INTERFACE) == 0 ||
644 (m1.owner.flags_field & INTERFACE) != 0) &&
645 m2.overrides(m1, m2Owner, types, false))
646 return m2;
647 boolean m1Abstract = (m1.flags() & ABSTRACT) != 0;
648 boolean m2Abstract = (m2.flags() & ABSTRACT) != 0;
649 if (m1Abstract && !m2Abstract) return m2;
650 if (m2Abstract && !m1Abstract) return m1;
651 // both abstract or both concrete
652 if (!m1Abstract && !m2Abstract)
653 return new AmbiguityError(m1, m2);
654 // check for same erasure
655 if (!types.isSameType(m1.erasure(types), m2.erasure(types)))
656 return new AmbiguityError(m1, m2);
657 // both abstract, neither overridden; merge throws clause and result type
658 Symbol result;
659 Type result2 = mt2.getReturnType();;
660 if (mt2.tag == FORALL)
661 result2 = types.subst(result2, ((ForAll)mt2).tvars, ((ForAll)mt1).tvars);
662 if (types.isSubtype(mt1.getReturnType(), result2)) {
663 result = m1;
664 } else if (types.isSubtype(result2, mt1.getReturnType())) {
665 result = m2;
666 } else {
667 // Theoretically, this can't happen, but it is possible
668 // due to error recovery or mixing incompatible class files
669 return new AmbiguityError(m1, m2);
670 }
671 result = result.clone(result.owner);
672 result.type = (Type)result.type.clone();
673 result.type.setThrown(chk.intersect(mt1.getThrownTypes(),
674 mt2.getThrownTypes()));
675 return result;
676 }
677 if (m1SignatureMoreSpecific) return m1;
678 if (m2SignatureMoreSpecific) return m2;
679 return new AmbiguityError(m1, m2);
680 case AMBIGUOUS:
681 AmbiguityError e = (AmbiguityError)m2;
682 Symbol err1 = mostSpecific(m1, e.sym1, env, site, allowBoxing, useVarargs);
683 Symbol err2 = mostSpecific(m1, e.sym2, env, site, allowBoxing, useVarargs);
684 if (err1 == err2) return err1;
685 if (err1 == e.sym1 && err2 == e.sym2) return m2;
686 if (err1 instanceof AmbiguityError &&
687 err2 instanceof AmbiguityError &&
688 ((AmbiguityError)err1).sym1 == ((AmbiguityError)err2).sym1)
689 return new AmbiguityError(m1, m2);
690 else
691 return new AmbiguityError(err1, err2);
692 default:
693 throw new AssertionError();
694 }
695 }
697 /** Find best qualified method matching given name, type and value
698 * arguments.
699 * @param env The current environment.
700 * @param site The original type from where the selection
701 * takes place.
702 * @param name The method's name.
703 * @param argtypes The method's value arguments.
704 * @param typeargtypes The method's type arguments
705 * @param allowBoxing Allow boxing conversions of arguments.
706 * @param useVarargs Box trailing arguments into an array for varargs.
707 */
708 Symbol findMethod(Env<AttrContext> env,
709 Type site,
710 Name name,
711 List<Type> argtypes,
712 List<Type> typeargtypes,
713 boolean allowBoxing,
714 boolean useVarargs,
715 boolean operator) {
716 return findMethod(env,
717 site,
718 name,
719 argtypes,
720 typeargtypes,
721 site.tsym.type,
722 true,
723 methodNotFound,
724 allowBoxing,
725 useVarargs,
726 operator);
727 }
728 // where
729 private Symbol findMethod(Env<AttrContext> env,
730 Type site,
731 Name name,
732 List<Type> argtypes,
733 List<Type> typeargtypes,
734 Type intype,
735 boolean abstractok,
736 Symbol bestSoFar,
737 boolean allowBoxing,
738 boolean useVarargs,
739 boolean operator) {
740 for (Type ct = intype; ct.tag == CLASS || ct.tag == TYPEVAR; ct = types.supertype(ct)) {
741 while (ct.tag == TYPEVAR)
742 ct = ct.getUpperBound();
743 ClassSymbol c = (ClassSymbol)ct.tsym;
744 if ((c.flags() & (ABSTRACT | INTERFACE)) == 0)
745 abstractok = false;
746 for (Scope.Entry e = c.members().lookup(name);
747 e.scope != null;
748 e = e.next()) {
749 //- System.out.println(" e " + e.sym);
750 if (e.sym.kind == MTH &&
751 (e.sym.flags_field & SYNTHETIC) == 0) {
752 bestSoFar = selectBest(env, site, argtypes, typeargtypes,
753 e.sym, bestSoFar,
754 allowBoxing,
755 useVarargs,
756 operator);
757 }
758 }
759 //- System.out.println(" - " + bestSoFar);
760 if (abstractok) {
761 Symbol concrete = methodNotFound;
762 if ((bestSoFar.flags() & ABSTRACT) == 0)
763 concrete = bestSoFar;
764 for (List<Type> l = types.interfaces(c.type);
765 l.nonEmpty();
766 l = l.tail) {
767 bestSoFar = findMethod(env, site, name, argtypes,
768 typeargtypes,
769 l.head, abstractok, bestSoFar,
770 allowBoxing, useVarargs, operator);
771 }
772 if (concrete != bestSoFar &&
773 concrete.kind < ERR && bestSoFar.kind < ERR &&
774 types.isSubSignature(concrete.type, bestSoFar.type))
775 bestSoFar = concrete;
776 }
777 }
778 return bestSoFar;
779 }
781 /** Find unqualified method matching given name, type and value arguments.
782 * @param env The current environment.
783 * @param name The method's name.
784 * @param argtypes The method's value arguments.
785 * @param typeargtypes The method's type arguments.
786 * @param allowBoxing Allow boxing conversions of arguments.
787 * @param useVarargs Box trailing arguments into an array for varargs.
788 */
789 Symbol findFun(Env<AttrContext> env, Name name,
790 List<Type> argtypes, List<Type> typeargtypes,
791 boolean allowBoxing, boolean useVarargs) {
792 Symbol bestSoFar = methodNotFound;
793 Symbol sym;
794 Env<AttrContext> env1 = env;
795 boolean staticOnly = false;
796 while (env1.outer != null) {
797 if (isStatic(env1)) staticOnly = true;
798 sym = findMethod(
799 env1, env1.enclClass.sym.type, name, argtypes, typeargtypes,
800 allowBoxing, useVarargs, false);
801 if (sym.exists()) {
802 if (staticOnly &&
803 sym.kind == MTH &&
804 sym.owner.kind == TYP &&
805 (sym.flags() & STATIC) == 0) return new StaticError(sym);
806 else return sym;
807 } else if (sym.kind < bestSoFar.kind) {
808 bestSoFar = sym;
809 }
810 if ((env1.enclClass.sym.flags() & STATIC) != 0) staticOnly = true;
811 env1 = env1.outer;
812 }
814 sym = findMethod(env, syms.predefClass.type, name, argtypes,
815 typeargtypes, allowBoxing, useVarargs, false);
816 if (sym.exists())
817 return sym;
819 Scope.Entry e = env.toplevel.namedImportScope.lookup(name);
820 for (; e.scope != null; e = e.next()) {
821 sym = e.sym;
822 Type origin = e.getOrigin().owner.type;
823 if (sym.kind == MTH) {
824 if (e.sym.owner.type != origin)
825 sym = sym.clone(e.getOrigin().owner);
826 if (!isAccessible(env, origin, sym))
827 sym = new AccessError(env, origin, sym);
828 bestSoFar = selectBest(env, origin,
829 argtypes, typeargtypes,
830 sym, bestSoFar,
831 allowBoxing, useVarargs, false);
832 }
833 }
834 if (bestSoFar.exists())
835 return bestSoFar;
837 e = env.toplevel.starImportScope.lookup(name);
838 for (; e.scope != null; e = e.next()) {
839 sym = e.sym;
840 Type origin = e.getOrigin().owner.type;
841 if (sym.kind == MTH) {
842 if (e.sym.owner.type != origin)
843 sym = sym.clone(e.getOrigin().owner);
844 if (!isAccessible(env, origin, sym))
845 sym = new AccessError(env, origin, sym);
846 bestSoFar = selectBest(env, origin,
847 argtypes, typeargtypes,
848 sym, bestSoFar,
849 allowBoxing, useVarargs, false);
850 }
851 }
852 return bestSoFar;
853 }
855 /** Load toplevel or member class with given fully qualified name and
856 * verify that it is accessible.
857 * @param env The current environment.
858 * @param name The fully qualified name of the class to be loaded.
859 */
860 Symbol loadClass(Env<AttrContext> env, Name name) {
861 try {
862 ClassSymbol c = reader.loadClass(name);
863 return isAccessible(env, c) ? c : new AccessError(c);
864 } catch (ClassReader.BadClassFile err) {
865 throw err;
866 } catch (CompletionFailure ex) {
867 return typeNotFound;
868 }
869 }
871 /** Find qualified member type.
872 * @param env The current environment.
873 * @param site The original type from where the selection takes
874 * place.
875 * @param name The type's name.
876 * @param c The class to search for the member type. This is
877 * always a superclass or implemented interface of
878 * site's class.
879 */
880 Symbol findMemberType(Env<AttrContext> env,
881 Type site,
882 Name name,
883 TypeSymbol c) {
884 Symbol bestSoFar = typeNotFound;
885 Symbol sym;
886 Scope.Entry e = c.members().lookup(name);
887 while (e.scope != null) {
888 if (e.sym.kind == TYP) {
889 return isAccessible(env, site, e.sym)
890 ? e.sym
891 : new AccessError(env, site, e.sym);
892 }
893 e = e.next();
894 }
895 Type st = types.supertype(c.type);
896 if (st != null && st.tag == CLASS) {
897 sym = findMemberType(env, site, name, st.tsym);
898 if (sym.kind < bestSoFar.kind) bestSoFar = sym;
899 }
900 for (List<Type> l = types.interfaces(c.type);
901 bestSoFar.kind != AMBIGUOUS && l.nonEmpty();
902 l = l.tail) {
903 sym = findMemberType(env, site, name, l.head.tsym);
904 if (bestSoFar.kind < AMBIGUOUS && sym.kind < AMBIGUOUS &&
905 sym.owner != bestSoFar.owner)
906 bestSoFar = new AmbiguityError(bestSoFar, sym);
907 else if (sym.kind < bestSoFar.kind)
908 bestSoFar = sym;
909 }
910 return bestSoFar;
911 }
913 /** Find a global type in given scope and load corresponding class.
914 * @param env The current environment.
915 * @param scope The scope in which to look for the type.
916 * @param name The type's name.
917 */
918 Symbol findGlobalType(Env<AttrContext> env, Scope scope, Name name) {
919 Symbol bestSoFar = typeNotFound;
920 for (Scope.Entry e = scope.lookup(name); e.scope != null; e = e.next()) {
921 Symbol sym = loadClass(env, e.sym.flatName());
922 if (bestSoFar.kind == TYP && sym.kind == TYP &&
923 bestSoFar != sym)
924 return new AmbiguityError(bestSoFar, sym);
925 else if (sym.kind < bestSoFar.kind)
926 bestSoFar = sym;
927 }
928 return bestSoFar;
929 }
931 /** Find an unqualified type symbol.
932 * @param env The current environment.
933 * @param name The type's name.
934 */
935 Symbol findType(Env<AttrContext> env, Name name) {
936 Symbol bestSoFar = typeNotFound;
937 Symbol sym;
938 boolean staticOnly = false;
939 for (Env<AttrContext> env1 = env; env1.outer != null; env1 = env1.outer) {
940 if (isStatic(env1)) staticOnly = true;
941 for (Scope.Entry e = env1.info.scope.lookup(name);
942 e.scope != null;
943 e = e.next()) {
944 if (e.sym.kind == TYP) {
945 if (staticOnly &&
946 e.sym.type.tag == TYPEVAR &&
947 e.sym.owner.kind == TYP) return new StaticError(e.sym);
948 return e.sym;
949 }
950 }
952 sym = findMemberType(env1, env1.enclClass.sym.type, name,
953 env1.enclClass.sym);
954 if (staticOnly && sym.kind == TYP &&
955 sym.type.tag == CLASS &&
956 sym.type.getEnclosingType().tag == CLASS &&
957 env1.enclClass.sym.type.isParameterized() &&
958 sym.type.getEnclosingType().isParameterized())
959 return new StaticError(sym);
960 else if (sym.exists()) return sym;
961 else if (sym.kind < bestSoFar.kind) bestSoFar = sym;
963 JCClassDecl encl = env1.baseClause ? (JCClassDecl)env1.tree : env1.enclClass;
964 if ((encl.sym.flags() & STATIC) != 0)
965 staticOnly = true;
966 }
968 if (env.tree.getTag() != JCTree.IMPORT) {
969 sym = findGlobalType(env, env.toplevel.namedImportScope, name);
970 if (sym.exists()) return sym;
971 else if (sym.kind < bestSoFar.kind) bestSoFar = sym;
973 sym = findGlobalType(env, env.toplevel.packge.members(), name);
974 if (sym.exists()) return sym;
975 else if (sym.kind < bestSoFar.kind) bestSoFar = sym;
977 sym = findGlobalType(env, env.toplevel.starImportScope, name);
978 if (sym.exists()) return sym;
979 else if (sym.kind < bestSoFar.kind) bestSoFar = sym;
980 }
982 return bestSoFar;
983 }
985 /** Find an unqualified identifier which matches a specified kind set.
986 * @param env The current environment.
987 * @param name The indentifier's name.
988 * @param kind Indicates the possible symbol kinds
989 * (a subset of VAL, TYP, PCK).
990 */
991 Symbol findIdent(Env<AttrContext> env, Name name, int kind) {
992 Symbol bestSoFar = typeNotFound;
993 Symbol sym;
995 if ((kind & VAR) != 0) {
996 sym = findVar(env, name);
997 if (sym.exists()) return sym;
998 else if (sym.kind < bestSoFar.kind) bestSoFar = sym;
999 }
1001 if ((kind & TYP) != 0) {
1002 sym = findType(env, name);
1003 if (sym.exists()) return sym;
1004 else if (sym.kind < bestSoFar.kind) bestSoFar = sym;
1005 }
1007 if ((kind & PCK) != 0) return reader.enterPackage(name);
1008 else return bestSoFar;
1009 }
1011 /** Find an identifier in a package which matches a specified kind set.
1012 * @param env The current environment.
1013 * @param name The identifier's name.
1014 * @param kind Indicates the possible symbol kinds
1015 * (a nonempty subset of TYP, PCK).
1016 */
1017 Symbol findIdentInPackage(Env<AttrContext> env, TypeSymbol pck,
1018 Name name, int kind) {
1019 Name fullname = TypeSymbol.formFullName(name, pck);
1020 Symbol bestSoFar = typeNotFound;
1021 PackageSymbol pack = null;
1022 if ((kind & PCK) != 0) {
1023 pack = reader.enterPackage(fullname);
1024 if (pack.exists()) return pack;
1025 }
1026 if ((kind & TYP) != 0) {
1027 Symbol sym = loadClass(env, fullname);
1028 if (sym.exists()) {
1029 // don't allow programs to use flatnames
1030 if (name == sym.name) return sym;
1031 }
1032 else if (sym.kind < bestSoFar.kind) bestSoFar = sym;
1033 }
1034 return (pack != null) ? pack : bestSoFar;
1035 }
1037 /** Find an identifier among the members of a given type `site'.
1038 * @param env The current environment.
1039 * @param site The type containing the symbol to be found.
1040 * @param name The identifier's name.
1041 * @param kind Indicates the possible symbol kinds
1042 * (a subset of VAL, TYP).
1043 */
1044 Symbol findIdentInType(Env<AttrContext> env, Type site,
1045 Name name, int kind) {
1046 Symbol bestSoFar = typeNotFound;
1047 Symbol sym;
1048 if ((kind & VAR) != 0) {
1049 sym = findField(env, site, name, site.tsym);
1050 if (sym.exists()) return sym;
1051 else if (sym.kind < bestSoFar.kind) bestSoFar = sym;
1052 }
1054 if ((kind & TYP) != 0) {
1055 sym = findMemberType(env, site, name, site.tsym);
1056 if (sym.exists()) return sym;
1057 else if (sym.kind < bestSoFar.kind) bestSoFar = sym;
1058 }
1059 return bestSoFar;
1060 }
1062 /* ***************************************************************************
1063 * Access checking
1064 * The following methods convert ResolveErrors to ErrorSymbols, issuing
1065 * an error message in the process
1066 ****************************************************************************/
1068 /** If `sym' is a bad symbol: report error and return errSymbol
1069 * else pass through unchanged,
1070 * additional arguments duplicate what has been used in trying to find the
1071 * symbol (--> flyweight pattern). This improves performance since we
1072 * expect misses to happen frequently.
1073 *
1074 * @param sym The symbol that was found, or a ResolveError.
1075 * @param pos The position to use for error reporting.
1076 * @param site The original type from where the selection took place.
1077 * @param name The symbol's name.
1078 * @param argtypes The invocation's value arguments,
1079 * if we looked for a method.
1080 * @param typeargtypes The invocation's type arguments,
1081 * if we looked for a method.
1082 */
1083 Symbol access(Symbol sym,
1084 DiagnosticPosition pos,
1085 Type site,
1086 Name name,
1087 boolean qualified,
1088 List<Type> argtypes,
1089 List<Type> typeargtypes) {
1090 if (sym.kind >= AMBIGUOUS) {
1091 // printscopes(site.tsym.members());//DEBUG
1092 if (!site.isErroneous() &&
1093 !Type.isErroneous(argtypes) &&
1094 (typeargtypes==null || !Type.isErroneous(typeargtypes)))
1095 ((ResolveError)sym).report(log, pos, site, name, argtypes, typeargtypes);
1096 do {
1097 sym = ((ResolveError)sym).sym;
1098 } while (sym.kind >= AMBIGUOUS);
1099 if (sym == syms.errSymbol // preserve the symbol name through errors
1100 || ((sym.kind & ERRONEOUS) == 0 // make sure an error symbol is returned
1101 && (sym.kind & TYP) != 0))
1102 sym = new ErrorType(name, qualified?site.tsym:syms.noSymbol).tsym;
1103 }
1104 return sym;
1105 }
1107 /** Same as above, but without type arguments and arguments.
1108 */
1109 Symbol access(Symbol sym,
1110 DiagnosticPosition pos,
1111 Type site,
1112 Name name,
1113 boolean qualified) {
1114 if (sym.kind >= AMBIGUOUS)
1115 return access(sym, pos, site, name, qualified, List.<Type>nil(), null);
1116 else
1117 return sym;
1118 }
1120 /** Check that sym is not an abstract method.
1121 */
1122 void checkNonAbstract(DiagnosticPosition pos, Symbol sym) {
1123 if ((sym.flags() & ABSTRACT) != 0)
1124 log.error(pos, "abstract.cant.be.accessed.directly",
1125 kindName(sym), sym, sym.location());
1126 }
1128 /* ***************************************************************************
1129 * Debugging
1130 ****************************************************************************/
1132 /** print all scopes starting with scope s and proceeding outwards.
1133 * used for debugging.
1134 */
1135 public void printscopes(Scope s) {
1136 while (s != null) {
1137 if (s.owner != null)
1138 System.err.print(s.owner + ": ");
1139 for (Scope.Entry e = s.elems; e != null; e = e.sibling) {
1140 if ((e.sym.flags() & ABSTRACT) != 0)
1141 System.err.print("abstract ");
1142 System.err.print(e.sym + " ");
1143 }
1144 System.err.println();
1145 s = s.next;
1146 }
1147 }
1149 void printscopes(Env<AttrContext> env) {
1150 while (env.outer != null) {
1151 System.err.println("------------------------------");
1152 printscopes(env.info.scope);
1153 env = env.outer;
1154 }
1155 }
1157 public void printscopes(Type t) {
1158 while (t.tag == CLASS) {
1159 printscopes(t.tsym.members());
1160 t = types.supertype(t);
1161 }
1162 }
1164 /* ***************************************************************************
1165 * Name resolution
1166 * Naming conventions are as for symbol lookup
1167 * Unlike the find... methods these methods will report access errors
1168 ****************************************************************************/
1170 /** Resolve an unqualified (non-method) identifier.
1171 * @param pos The position to use for error reporting.
1172 * @param env The environment current at the identifier use.
1173 * @param name The identifier's name.
1174 * @param kind The set of admissible symbol kinds for the identifier.
1175 */
1176 Symbol resolveIdent(DiagnosticPosition pos, Env<AttrContext> env,
1177 Name name, int kind) {
1178 return access(
1179 findIdent(env, name, kind),
1180 pos, env.enclClass.sym.type, name, false);
1181 }
1183 /** Resolve an unqualified method identifier.
1184 * @param pos The position to use for error reporting.
1185 * @param env The environment current at the method invocation.
1186 * @param name The identifier's name.
1187 * @param argtypes The types of the invocation's value arguments.
1188 * @param typeargtypes The types of the invocation's type arguments.
1189 */
1190 Symbol resolveMethod(DiagnosticPosition pos,
1191 Env<AttrContext> env,
1192 Name name,
1193 List<Type> argtypes,
1194 List<Type> typeargtypes) {
1195 Symbol sym = findFun(env, name, argtypes, typeargtypes, false, env.info.varArgs=false);
1196 if (varargsEnabled && sym.kind >= WRONG_MTHS) {
1197 sym = findFun(env, name, argtypes, typeargtypes, true, false);
1198 if (sym.kind >= WRONG_MTHS)
1199 sym = findFun(env, name, argtypes, typeargtypes, true, env.info.varArgs=true);
1200 }
1201 if (sym.kind >= AMBIGUOUS) {
1202 sym = access(
1203 sym, pos, env.enclClass.sym.type, name, false, argtypes, typeargtypes);
1204 }
1205 return sym;
1206 }
1208 /** Resolve a qualified method identifier
1209 * @param pos The position to use for error reporting.
1210 * @param env The environment current at the method invocation.
1211 * @param site The type of the qualifying expression, in which
1212 * identifier is searched.
1213 * @param name The identifier's name.
1214 * @param argtypes The types of the invocation's value arguments.
1215 * @param typeargtypes The types of the invocation's type arguments.
1216 */
1217 Symbol resolveQualifiedMethod(DiagnosticPosition pos, Env<AttrContext> env,
1218 Type site, Name name, List<Type> argtypes,
1219 List<Type> typeargtypes) {
1220 Symbol sym = findMethod(env, site, name, argtypes, typeargtypes, false,
1221 env.info.varArgs=false, false);
1222 if (varargsEnabled && sym.kind >= WRONG_MTHS) {
1223 sym = findMethod(env, site, name, argtypes, typeargtypes, true,
1224 false, false);
1225 if (sym.kind >= WRONG_MTHS)
1226 sym = findMethod(env, site, name, argtypes, typeargtypes, true,
1227 env.info.varArgs=true, false);
1228 }
1229 if (sym.kind >= AMBIGUOUS) {
1230 sym = access(sym, pos, site, name, true, argtypes, typeargtypes);
1231 }
1232 return sym;
1233 }
1235 /** Resolve a qualified method identifier, throw a fatal error if not
1236 * found.
1237 * @param pos The position to use for error reporting.
1238 * @param env The environment current at the method invocation.
1239 * @param site The type of the qualifying expression, in which
1240 * identifier is searched.
1241 * @param name The identifier's name.
1242 * @param argtypes The types of the invocation's value arguments.
1243 * @param typeargtypes The types of the invocation's type arguments.
1244 */
1245 public MethodSymbol resolveInternalMethod(DiagnosticPosition pos, Env<AttrContext> env,
1246 Type site, Name name,
1247 List<Type> argtypes,
1248 List<Type> typeargtypes) {
1249 Symbol sym = resolveQualifiedMethod(
1250 pos, env, site, name, argtypes, typeargtypes);
1251 if (sym.kind == MTH) return (MethodSymbol)sym;
1252 else throw new FatalError(
1253 diags.fragment("fatal.err.cant.locate.meth",
1254 name));
1255 }
1257 /** Resolve constructor.
1258 * @param pos The position to use for error reporting.
1259 * @param env The environment current at the constructor invocation.
1260 * @param site The type of class for which a constructor is searched.
1261 * @param argtypes The types of the constructor invocation's value
1262 * arguments.
1263 * @param typeargtypes The types of the constructor invocation's type
1264 * arguments.
1265 */
1266 Symbol resolveConstructor(DiagnosticPosition pos,
1267 Env<AttrContext> env,
1268 Type site,
1269 List<Type> argtypes,
1270 List<Type> typeargtypes) {
1271 Symbol sym = resolveConstructor(pos, env, site, argtypes, typeargtypes, false, env.info.varArgs=false);
1272 if (varargsEnabled && sym.kind >= WRONG_MTHS) {
1273 sym = resolveConstructor(pos, env, site, argtypes, typeargtypes, true, false);
1274 if (sym.kind >= WRONG_MTHS)
1275 sym = resolveConstructor(pos, env, site, argtypes, typeargtypes, true, env.info.varArgs=true);
1276 }
1277 if (sym.kind >= AMBIGUOUS) {
1278 sym = access(sym, pos, site, names.init, true, argtypes, typeargtypes);
1279 }
1280 return sym;
1281 }
1283 /** Resolve constructor.
1284 * @param pos The position to use for error reporting.
1285 * @param env The environment current at the constructor invocation.
1286 * @param site The type of class for which a constructor is searched.
1287 * @param argtypes The types of the constructor invocation's value
1288 * arguments.
1289 * @param typeargtypes The types of the constructor invocation's type
1290 * arguments.
1291 * @param allowBoxing Allow boxing and varargs conversions.
1292 * @param useVarargs Box trailing arguments into an array for varargs.
1293 */
1294 Symbol resolveConstructor(DiagnosticPosition pos, Env<AttrContext> env,
1295 Type site, List<Type> argtypes,
1296 List<Type> typeargtypes,
1297 boolean allowBoxing,
1298 boolean useVarargs) {
1299 Symbol sym = findMethod(env, site,
1300 names.init, argtypes,
1301 typeargtypes, allowBoxing,
1302 useVarargs, false);
1303 if ((sym.flags() & DEPRECATED) != 0 &&
1304 (env.info.scope.owner.flags() & DEPRECATED) == 0 &&
1305 env.info.scope.owner.outermostClass() != sym.outermostClass())
1306 chk.warnDeprecated(pos, sym);
1307 return sym;
1308 }
1310 /** Resolve a constructor, throw a fatal error if not found.
1311 * @param pos The position to use for error reporting.
1312 * @param env The environment current at the method invocation.
1313 * @param site The type to be constructed.
1314 * @param argtypes The types of the invocation's value arguments.
1315 * @param typeargtypes The types of the invocation's type arguments.
1316 */
1317 public MethodSymbol resolveInternalConstructor(DiagnosticPosition pos, Env<AttrContext> env,
1318 Type site,
1319 List<Type> argtypes,
1320 List<Type> typeargtypes) {
1321 Symbol sym = resolveConstructor(
1322 pos, env, site, argtypes, typeargtypes);
1323 if (sym.kind == MTH) return (MethodSymbol)sym;
1324 else throw new FatalError(
1325 diags.fragment("fatal.err.cant.locate.ctor", site));
1326 }
1328 /** Resolve operator.
1329 * @param pos The position to use for error reporting.
1330 * @param optag The tag of the operation tree.
1331 * @param env The environment current at the operation.
1332 * @param argtypes The types of the operands.
1333 */
1334 Symbol resolveOperator(DiagnosticPosition pos, int optag,
1335 Env<AttrContext> env, List<Type> argtypes) {
1336 Name name = treeinfo.operatorName(optag);
1337 Symbol sym = findMethod(env, syms.predefClass.type, name, argtypes,
1338 null, false, false, true);
1339 if (boxingEnabled && sym.kind >= WRONG_MTHS)
1340 sym = findMethod(env, syms.predefClass.type, name, argtypes,
1341 null, true, false, true);
1342 return access(sym, pos, env.enclClass.sym.type, name,
1343 false, argtypes, null);
1344 }
1346 /** Resolve operator.
1347 * @param pos The position to use for error reporting.
1348 * @param optag The tag of the operation tree.
1349 * @param env The environment current at the operation.
1350 * @param arg The type of the operand.
1351 */
1352 Symbol resolveUnaryOperator(DiagnosticPosition pos, int optag, Env<AttrContext> env, Type arg) {
1353 return resolveOperator(pos, optag, env, List.of(arg));
1354 }
1356 /** Resolve binary operator.
1357 * @param pos The position to use for error reporting.
1358 * @param optag The tag of the operation tree.
1359 * @param env The environment current at the operation.
1360 * @param left The types of the left operand.
1361 * @param right The types of the right operand.
1362 */
1363 Symbol resolveBinaryOperator(DiagnosticPosition pos,
1364 int optag,
1365 Env<AttrContext> env,
1366 Type left,
1367 Type right) {
1368 return resolveOperator(pos, optag, env, List.of(left, right));
1369 }
1371 /**
1372 * Resolve `c.name' where name == this or name == super.
1373 * @param pos The position to use for error reporting.
1374 * @param env The environment current at the expression.
1375 * @param c The qualifier.
1376 * @param name The identifier's name.
1377 */
1378 Symbol resolveSelf(DiagnosticPosition pos,
1379 Env<AttrContext> env,
1380 TypeSymbol c,
1381 Name name) {
1382 Env<AttrContext> env1 = env;
1383 boolean staticOnly = false;
1384 while (env1.outer != null) {
1385 if (isStatic(env1)) staticOnly = true;
1386 if (env1.enclClass.sym == c) {
1387 Symbol sym = env1.info.scope.lookup(name).sym;
1388 if (sym != null) {
1389 if (staticOnly) sym = new StaticError(sym);
1390 return access(sym, pos, env.enclClass.sym.type,
1391 name, true);
1392 }
1393 }
1394 if ((env1.enclClass.sym.flags() & STATIC) != 0) staticOnly = true;
1395 env1 = env1.outer;
1396 }
1397 log.error(pos, "not.encl.class", c);
1398 return syms.errSymbol;
1399 }
1401 /**
1402 * Resolve `c.this' for an enclosing class c that contains the
1403 * named member.
1404 * @param pos The position to use for error reporting.
1405 * @param env The environment current at the expression.
1406 * @param member The member that must be contained in the result.
1407 */
1408 Symbol resolveSelfContaining(DiagnosticPosition pos,
1409 Env<AttrContext> env,
1410 Symbol member) {
1411 Name name = names._this;
1412 Env<AttrContext> env1 = env;
1413 boolean staticOnly = false;
1414 while (env1.outer != null) {
1415 if (isStatic(env1)) staticOnly = true;
1416 if (env1.enclClass.sym.isSubClass(member.owner, types) &&
1417 isAccessible(env, env1.enclClass.sym.type, member)) {
1418 Symbol sym = env1.info.scope.lookup(name).sym;
1419 if (sym != null) {
1420 if (staticOnly) sym = new StaticError(sym);
1421 return access(sym, pos, env.enclClass.sym.type,
1422 name, true);
1423 }
1424 }
1425 if ((env1.enclClass.sym.flags() & STATIC) != 0)
1426 staticOnly = true;
1427 env1 = env1.outer;
1428 }
1429 log.error(pos, "encl.class.required", member);
1430 return syms.errSymbol;
1431 }
1433 /**
1434 * Resolve an appropriate implicit this instance for t's container.
1435 * JLS2 8.8.5.1 and 15.9.2
1436 */
1437 Type resolveImplicitThis(DiagnosticPosition pos, Env<AttrContext> env, Type t) {
1438 Type thisType = (((t.tsym.owner.kind & (MTH|VAR)) != 0)
1439 ? resolveSelf(pos, env, t.getEnclosingType().tsym, names._this)
1440 : resolveSelfContaining(pos, env, t.tsym)).type;
1441 if (env.info.isSelfCall && thisType.tsym == env.enclClass.sym)
1442 log.error(pos, "cant.ref.before.ctor.called", "this");
1443 return thisType;
1444 }
1446 /* ***************************************************************************
1447 * ResolveError classes, indicating error situations when accessing symbols
1448 ****************************************************************************/
1450 public void logAccessError(Env<AttrContext> env, JCTree tree, Type type) {
1451 AccessError error = new AccessError(env, type.getEnclosingType(), type.tsym);
1452 error.report(log, tree.pos(), type.getEnclosingType(), null, null, null);
1453 }
1455 /** Root class for resolve errors.
1456 * Instances of this class indicate "Symbol not found".
1457 * Instances of subclass indicate other errors.
1458 */
1459 private class ResolveError extends Symbol {
1461 ResolveError(int kind, Symbol sym, String debugName) {
1462 super(kind, 0, null, null, null);
1463 this.debugName = debugName;
1464 this.sym = sym;
1465 }
1467 /** The name of the kind of error, for debugging only.
1468 */
1469 final String debugName;
1471 /** The symbol that was determined by resolution, or errSymbol if none
1472 * was found.
1473 */
1474 final Symbol sym;
1476 /** The symbol that was a close mismatch, or null if none was found.
1477 * wrongSym is currently set if a simgle method with the correct name, but
1478 * the wrong parameters was found.
1479 */
1480 Symbol wrongSym;
1482 /** An auxiliary explanation set in case of instantiation errors.
1483 */
1484 JCDiagnostic explanation;
1487 public <R, P> R accept(ElementVisitor<R, P> v, P p) {
1488 throw new AssertionError();
1489 }
1491 /** Print the (debug only) name of the kind of error.
1492 */
1493 public String toString() {
1494 return debugName + " wrongSym=" + wrongSym + " explanation=" + explanation;
1495 }
1497 /** Update wrongSym and explanation and return this.
1498 */
1499 ResolveError setWrongSym(Symbol sym, JCDiagnostic explanation) {
1500 this.wrongSym = sym;
1501 this.explanation = explanation;
1502 return this;
1503 }
1505 /** Update wrongSym and return this.
1506 */
1507 ResolveError setWrongSym(Symbol sym) {
1508 this.wrongSym = sym;
1509 this.explanation = null;
1510 return this;
1511 }
1513 public boolean exists() {
1514 switch (kind) {
1515 case HIDDEN:
1516 case ABSENT_VAR:
1517 case ABSENT_MTH:
1518 case ABSENT_TYP:
1519 return false;
1520 default:
1521 return true;
1522 }
1523 }
1525 /** Report error.
1526 * @param log The error log to be used for error reporting.
1527 * @param pos The position to be used for error reporting.
1528 * @param site The original type from where the selection took place.
1529 * @param name The name of the symbol to be resolved.
1530 * @param argtypes The invocation's value arguments,
1531 * if we looked for a method.
1532 * @param typeargtypes The invocation's type arguments,
1533 * if we looked for a method.
1534 */
1535 void report(Log log, DiagnosticPosition pos, Type site, Name name,
1536 List<Type> argtypes, List<Type> typeargtypes) {
1537 if (argtypes == null)
1538 argtypes = List.nil();
1539 if (typeargtypes == null)
1540 typeargtypes = List.nil();
1541 if (name != name.table.error) {
1542 KindName kindname = absentKind(kind);
1543 Name idname = name;
1544 if (kind >= WRONG_MTHS && kind <= ABSENT_MTH) {
1545 if (isOperator(name)) {
1546 log.error(pos, "operator.cant.be.applied",
1547 name, argtypes);
1548 return;
1549 }
1550 if (name == name.table.init) {
1551 kindname = KindName.CONSTRUCTOR;
1552 idname = site.tsym.name;
1553 }
1554 }
1555 if (kind == WRONG_MTH) {
1556 Symbol ws = wrongSym.asMemberOf(site, types);
1557 log.error(pos,
1558 "cant.apply.symbol" + (explanation != null ? ".1" : ""),
1559 kindname,
1560 ws.name == names.init ? ws.owner.name : ws.name,
1561 ws.type.getParameterTypes(),
1562 argtypes,
1563 kindName(ws.owner),
1564 ws.owner.type,
1565 explanation);
1566 } else if (site.tsym.name.len != 0) {
1567 if (site.tsym.kind == PCK && !site.tsym.exists())
1568 log.error(pos, "doesnt.exist", site.tsym);
1569 else {
1570 String errKey = getErrorKey("cant.resolve.location",
1571 argtypes, typeargtypes,
1572 kindname);
1573 log.error(pos, errKey, kindname, idname, //symbol kindname, name
1574 typeargtypes, argtypes, //type parameters and arguments (if any)
1575 typeKindName(site), site); //location kindname, type
1576 }
1577 } else {
1578 String errKey = getErrorKey("cant.resolve",
1579 argtypes, typeargtypes,
1580 kindname);
1581 log.error(pos, errKey, kindname, idname, //symbol kindname, name
1582 typeargtypes, argtypes); //type parameters and arguments (if any)
1583 }
1584 }
1585 }
1586 //where
1587 String getErrorKey(String key, List<Type> argtypes, List<Type> typeargtypes, KindName kindname) {
1588 String suffix = "";
1589 switch (kindname) {
1590 case METHOD:
1591 case CONSTRUCTOR: {
1592 suffix += ".args";
1593 suffix += typeargtypes.nonEmpty() ? ".params" : "";
1594 }
1595 }
1596 return key + suffix;
1597 }
1599 /** A name designates an operator if it consists
1600 * of a non-empty sequence of operator symbols +-~!/*%&|^<>=
1601 */
1602 boolean isOperator(Name name) {
1603 int i = 0;
1604 while (i < name.len &&
1605 "+-~!*/%&|^<>=".indexOf(name.byteAt(i)) >= 0) i++;
1606 return i > 0 && i == name.len;
1607 }
1608 }
1610 /** Resolve error class indicating that a symbol is not accessible.
1611 */
1612 class AccessError extends ResolveError {
1614 AccessError(Symbol sym) {
1615 this(null, null, sym);
1616 }
1618 AccessError(Env<AttrContext> env, Type site, Symbol sym) {
1619 super(HIDDEN, sym, "access error");
1620 this.env = env;
1621 this.site = site;
1622 if (debugResolve)
1623 log.error("proc.messager", sym + " @ " + site + " is inaccessible.");
1624 }
1626 private Env<AttrContext> env;
1627 private Type site;
1629 /** Report error.
1630 * @param log The error log to be used for error reporting.
1631 * @param pos The position to be used for error reporting.
1632 * @param site The original type from where the selection took place.
1633 * @param name The name of the symbol to be resolved.
1634 * @param argtypes The invocation's value arguments,
1635 * if we looked for a method.
1636 * @param typeargtypes The invocation's type arguments,
1637 * if we looked for a method.
1638 */
1639 void report(Log log, DiagnosticPosition pos, Type site, Name name,
1640 List<Type> argtypes, List<Type> typeargtypes) {
1641 if (sym.owner.type.tag != ERROR) {
1642 if (sym.name == sym.name.table.init && sym.owner != site.tsym)
1643 new ResolveError(ABSENT_MTH, sym.owner, "absent method " + sym).report(
1644 log, pos, site, name, argtypes, typeargtypes);
1645 if ((sym.flags() & PUBLIC) != 0
1646 || (env != null && this.site != null
1647 && !isAccessible(env, this.site)))
1648 log.error(pos, "not.def.access.class.intf.cant.access",
1649 sym, sym.location());
1650 else if ((sym.flags() & (PRIVATE | PROTECTED)) != 0)
1651 log.error(pos, "report.access", sym,
1652 asFlagSet(sym.flags() & (PRIVATE | PROTECTED)),
1653 sym.location());
1654 else
1655 log.error(pos, "not.def.public.cant.access",
1656 sym, sym.location());
1657 }
1658 }
1659 }
1661 /** Resolve error class indicating that an instance member was accessed
1662 * from a static context.
1663 */
1664 class StaticError extends ResolveError {
1665 StaticError(Symbol sym) {
1666 super(STATICERR, sym, "static error");
1667 }
1669 /** Report error.
1670 * @param log The error log to be used for error reporting.
1671 * @param pos The position to be used for error reporting.
1672 * @param site The original type from where the selection took place.
1673 * @param name The name of the symbol to be resolved.
1674 * @param argtypes The invocation's value arguments,
1675 * if we looked for a method.
1676 * @param typeargtypes The invocation's type arguments,
1677 * if we looked for a method.
1678 */
1679 void report(Log log,
1680 DiagnosticPosition pos,
1681 Type site,
1682 Name name,
1683 List<Type> argtypes,
1684 List<Type> typeargtypes) {
1685 Symbol errSym = ((sym.kind == TYP && sym.type.tag == CLASS)
1686 ? types.erasure(sym.type).tsym
1687 : sym);
1688 log.error(pos, "non-static.cant.be.ref",
1689 kindName(sym), errSym);
1690 }
1691 }
1693 /** Resolve error class indicating an ambiguous reference.
1694 */
1695 class AmbiguityError extends ResolveError {
1696 Symbol sym1;
1697 Symbol sym2;
1699 AmbiguityError(Symbol sym1, Symbol sym2) {
1700 super(AMBIGUOUS, sym1, "ambiguity error");
1701 this.sym1 = sym1;
1702 this.sym2 = sym2;
1703 }
1705 /** Report error.
1706 * @param log The error log to be used for error reporting.
1707 * @param pos The position to be used for error reporting.
1708 * @param site The original type from where the selection took place.
1709 * @param name The name of the symbol to be resolved.
1710 * @param argtypes The invocation's value arguments,
1711 * if we looked for a method.
1712 * @param typeargtypes The invocation's type arguments,
1713 * if we looked for a method.
1714 */
1715 void report(Log log, DiagnosticPosition pos, Type site, Name name,
1716 List<Type> argtypes, List<Type> typeargtypes) {
1717 AmbiguityError pair = this;
1718 while (true) {
1719 if (pair.sym1.kind == AMBIGUOUS)
1720 pair = (AmbiguityError)pair.sym1;
1721 else if (pair.sym2.kind == AMBIGUOUS)
1722 pair = (AmbiguityError)pair.sym2;
1723 else break;
1724 }
1725 Name sname = pair.sym1.name;
1726 if (sname == sname.table.init) sname = pair.sym1.owner.name;
1727 log.error(pos, "ref.ambiguous", sname,
1728 kindName(pair.sym1),
1729 pair.sym1,
1730 pair.sym1.location(site, types),
1731 kindName(pair.sym2),
1732 pair.sym2,
1733 pair.sym2.location(site, types));
1734 }
1735 }
1736 }
