Mercurial > jdk8-mips64-public > langtools / file revision
src/share/classes/com/sun/tools/javac/comp/Check.java@396b117c1743
src/share/classes/com/sun/tools/javac/comp/Check.java
Wed, 14 Apr 2010 12:23:29 +0100
- author
- mcimadamore
- date
- Wed, 14 Apr 2010 12:23:29 +0100
- changeset 536
- 396b117c1743
- parent 505
- 87eb6edd4f21
- child 537
- 9d9d08922405
- permissions
- -rw-r--r--
6939618: Revert 'simple' diamond implementation
Summary: backout changeset for 6840638
Reviewed-by: jjg
1 /*
2 * Copyright 1999-2009 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 java.util.*;
29 import java.util.Set;
31 import com.sun.tools.javac.code.*;
32 import com.sun.tools.javac.jvm.*;
33 import com.sun.tools.javac.tree.*;
34 import com.sun.tools.javac.util.*;
35 import com.sun.tools.javac.util.JCDiagnostic.DiagnosticPosition;
36 import com.sun.tools.javac.util.List;
38 import com.sun.tools.javac.tree.JCTree.*;
39 import com.sun.tools.javac.code.Lint;
40 import com.sun.tools.javac.code.Lint.LintCategory;
41 import com.sun.tools.javac.code.Type.*;
42 import com.sun.tools.javac.code.Symbol.*;
44 import static com.sun.tools.javac.code.Flags.*;
45 import static com.sun.tools.javac.code.Kinds.*;
46 import static com.sun.tools.javac.code.TypeTags.*;
48 /** Type checking helper class for the attribution phase.
49 *
50 * <p><b>This is NOT part of any API supported by Sun Microsystems. If
51 * you write code that depends on this, you do so at your own risk.
52 * This code and its internal interfaces are subject to change or
53 * deletion without notice.</b>
54 */
55 public class Check {
56 protected static final Context.Key<Check> checkKey =
57 new Context.Key<Check>();
59 private final Names names;
60 private final Log log;
61 private final Symtab syms;
62 private final Infer infer;
63 private final Types types;
64 private final JCDiagnostic.Factory diags;
65 private final boolean skipAnnotations;
66 private boolean warnOnSyntheticConflicts;
67 private final TreeInfo treeinfo;
69 // The set of lint options currently in effect. It is initialized
70 // from the context, and then is set/reset as needed by Attr as it
71 // visits all the various parts of the trees during attribution.
72 private Lint lint;
74 public static Check instance(Context context) {
75 Check instance = context.get(checkKey);
76 if (instance == null)
77 instance = new Check(context);
78 return instance;
79 }
81 protected Check(Context context) {
82 context.put(checkKey, this);
84 names = Names.instance(context);
85 log = Log.instance(context);
86 syms = Symtab.instance(context);
87 infer = Infer.instance(context);
88 this.types = Types.instance(context);
89 diags = JCDiagnostic.Factory.instance(context);
90 Options options = Options.instance(context);
91 lint = Lint.instance(context);
92 treeinfo = TreeInfo.instance(context);
94 Source source = Source.instance(context);
95 allowGenerics = source.allowGenerics();
96 allowAnnotations = source.allowAnnotations();
97 allowCovariantReturns = source.allowCovariantReturns();
98 complexInference = options.get("-complexinference") != null;
99 skipAnnotations = options.get("skipAnnotations") != null;
100 warnOnSyntheticConflicts = options.get("warnOnSyntheticConflicts") != null;
102 Target target = Target.instance(context);
103 syntheticNameChar = target.syntheticNameChar();
105 boolean verboseDeprecated = lint.isEnabled(LintCategory.DEPRECATION);
106 boolean verboseUnchecked = lint.isEnabled(LintCategory.UNCHECKED);
107 boolean verboseSunApi = lint.isEnabled(LintCategory.SUNAPI);
108 boolean enforceMandatoryWarnings = source.enforceMandatoryWarnings();
110 deprecationHandler = new MandatoryWarningHandler(log, verboseDeprecated,
111 enforceMandatoryWarnings, "deprecated");
112 uncheckedHandler = new MandatoryWarningHandler(log, verboseUnchecked,
113 enforceMandatoryWarnings, "unchecked");
114 sunApiHandler = new MandatoryWarningHandler(log, verboseSunApi,
115 enforceMandatoryWarnings, "sunapi");
116 }
118 /** Switch: generics enabled?
119 */
120 boolean allowGenerics;
122 /** Switch: annotations enabled?
123 */
124 boolean allowAnnotations;
126 /** Switch: covariant returns enabled?
127 */
128 boolean allowCovariantReturns;
130 /** Switch: -complexinference option set?
131 */
132 boolean complexInference;
134 /** Character for synthetic names
135 */
136 char syntheticNameChar;
138 /** A table mapping flat names of all compiled classes in this run to their
139 * symbols; maintained from outside.
140 */
141 public Map<Name,ClassSymbol> compiled = new HashMap<Name, ClassSymbol>();
143 /** A handler for messages about deprecated usage.
144 */
145 private MandatoryWarningHandler deprecationHandler;
147 /** A handler for messages about unchecked or unsafe usage.
148 */
149 private MandatoryWarningHandler uncheckedHandler;
151 /** A handler for messages about using Sun proprietary API.
152 */
153 private MandatoryWarningHandler sunApiHandler;
155 /* *************************************************************************
156 * Errors and Warnings
157 **************************************************************************/
159 Lint setLint(Lint newLint) {
160 Lint prev = lint;
161 lint = newLint;
162 return prev;
163 }
165 /** Warn about deprecated symbol.
166 * @param pos Position to be used for error reporting.
167 * @param sym The deprecated symbol.
168 */
169 void warnDeprecated(DiagnosticPosition pos, Symbol sym) {
170 if (!lint.isSuppressed(LintCategory.DEPRECATION))
171 deprecationHandler.report(pos, "has.been.deprecated", sym, sym.location());
172 }
174 /** Warn about unchecked operation.
175 * @param pos Position to be used for error reporting.
176 * @param msg A string describing the problem.
177 */
178 public void warnUnchecked(DiagnosticPosition pos, String msg, Object... args) {
179 if (!lint.isSuppressed(LintCategory.UNCHECKED))
180 uncheckedHandler.report(pos, msg, args);
181 }
183 /** Warn about using Sun proprietary API.
184 * @param pos Position to be used for error reporting.
185 * @param msg A string describing the problem.
186 */
187 public void warnSunApi(DiagnosticPosition pos, String msg, Object... args) {
188 if (!lint.isSuppressed(LintCategory.SUNAPI))
189 sunApiHandler.report(pos, msg, args);
190 }
192 public void warnStatic(DiagnosticPosition pos, String msg, Object... args) {
193 if (lint.isEnabled(LintCategory.STATIC))
194 log.warning(pos, msg, args);
195 }
197 /**
198 * Report any deferred diagnostics.
199 */
200 public void reportDeferredDiagnostics() {
201 deprecationHandler.reportDeferredDiagnostic();
202 uncheckedHandler.reportDeferredDiagnostic();
203 sunApiHandler.reportDeferredDiagnostic();
204 }
207 /** Report a failure to complete a class.
208 * @param pos Position to be used for error reporting.
209 * @param ex The failure to report.
210 */
211 public Type completionError(DiagnosticPosition pos, CompletionFailure ex) {
212 log.error(pos, "cant.access", ex.sym, ex.getDetailValue());
213 if (ex instanceof ClassReader.BadClassFile) throw new Abort();
214 else return syms.errType;
215 }
217 /** Report a type error.
218 * @param pos Position to be used for error reporting.
219 * @param problem A string describing the error.
220 * @param found The type that was found.
221 * @param req The type that was required.
222 */
223 Type typeError(DiagnosticPosition pos, Object problem, Type found, Type req) {
224 log.error(pos, "prob.found.req",
225 problem, found, req);
226 return types.createErrorType(found);
227 }
229 Type typeError(DiagnosticPosition pos, String problem, Type found, Type req, Object explanation) {
230 log.error(pos, "prob.found.req.1", problem, found, req, explanation);
231 return types.createErrorType(found);
232 }
234 /** Report an error that wrong type tag was found.
235 * @param pos Position to be used for error reporting.
236 * @param required An internationalized string describing the type tag
237 * required.
238 * @param found The type that was found.
239 */
240 Type typeTagError(DiagnosticPosition pos, Object required, Object found) {
241 // this error used to be raised by the parser,
242 // but has been delayed to this point:
243 if (found instanceof Type && ((Type)found).tag == VOID) {
244 log.error(pos, "illegal.start.of.type");
245 return syms.errType;
246 }
247 log.error(pos, "type.found.req", found, required);
248 return types.createErrorType(found instanceof Type ? (Type)found : syms.errType);
249 }
251 /** Report an error that symbol cannot be referenced before super
252 * has been called.
253 * @param pos Position to be used for error reporting.
254 * @param sym The referenced symbol.
255 */
256 void earlyRefError(DiagnosticPosition pos, Symbol sym) {
257 log.error(pos, "cant.ref.before.ctor.called", sym);
258 }
260 /** Report duplicate declaration error.
261 */
262 void duplicateError(DiagnosticPosition pos, Symbol sym) {
263 if (!sym.type.isErroneous()) {
264 log.error(pos, "already.defined", sym, sym.location());
265 }
266 }
268 /** Report array/varargs duplicate declaration
269 */
270 void varargsDuplicateError(DiagnosticPosition pos, Symbol sym1, Symbol sym2) {
271 if (!sym1.type.isErroneous() && !sym2.type.isErroneous()) {
272 log.error(pos, "array.and.varargs", sym1, sym2, sym2.location());
273 }
274 }
276 /* ************************************************************************
277 * duplicate declaration checking
278 *************************************************************************/
280 /** Check that variable does not hide variable with same name in
281 * immediately enclosing local scope.
282 * @param pos Position for error reporting.
283 * @param v The symbol.
284 * @param s The scope.
285 */
286 void checkTransparentVar(DiagnosticPosition pos, VarSymbol v, Scope s) {
287 if (s.next != null) {
288 for (Scope.Entry e = s.next.lookup(v.name);
289 e.scope != null && e.sym.owner == v.owner;
290 e = e.next()) {
291 if (e.sym.kind == VAR &&
292 (e.sym.owner.kind & (VAR | MTH)) != 0 &&
293 v.name != names.error) {
294 duplicateError(pos, e.sym);
295 return;
296 }
297 }
298 }
299 }
301 /** Check that a class or interface does not hide a class or
302 * interface with same name in immediately enclosing local scope.
303 * @param pos Position for error reporting.
304 * @param c The symbol.
305 * @param s The scope.
306 */
307 void checkTransparentClass(DiagnosticPosition pos, ClassSymbol c, Scope s) {
308 if (s.next != null) {
309 for (Scope.Entry e = s.next.lookup(c.name);
310 e.scope != null && e.sym.owner == c.owner;
311 e = e.next()) {
312 if (e.sym.kind == TYP &&
313 (e.sym.owner.kind & (VAR | MTH)) != 0 &&
314 c.name != names.error) {
315 duplicateError(pos, e.sym);
316 return;
317 }
318 }
319 }
320 }
322 /** Check that class does not have the same name as one of
323 * its enclosing classes, or as a class defined in its enclosing scope.
324 * return true if class is unique in its enclosing scope.
325 * @param pos Position for error reporting.
326 * @param name The class name.
327 * @param s The enclosing scope.
328 */
329 boolean checkUniqueClassName(DiagnosticPosition pos, Name name, Scope s) {
330 for (Scope.Entry e = s.lookup(name); e.scope == s; e = e.next()) {
331 if (e.sym.kind == TYP && e.sym.name != names.error) {
332 duplicateError(pos, e.sym);
333 return false;
334 }
335 }
336 for (Symbol sym = s.owner; sym != null; sym = sym.owner) {
337 if (sym.kind == TYP && sym.name == name && sym.name != names.error) {
338 duplicateError(pos, sym);
339 return true;
340 }
341 }
342 return true;
343 }
345 /* *************************************************************************
346 * Class name generation
347 **************************************************************************/
349 /** Return name of local class.
350 * This is of the form <enclClass> $ n <classname>
351 * where
352 * enclClass is the flat name of the enclosing class,
353 * classname is the simple name of the local class
354 */
355 Name localClassName(ClassSymbol c) {
356 for (int i=1; ; i++) {
357 Name flatname = names.
358 fromString("" + c.owner.enclClass().flatname +
359 syntheticNameChar + i +
360 c.name);
361 if (compiled.get(flatname) == null) return flatname;
362 }
363 }
365 /* *************************************************************************
366 * Type Checking
367 **************************************************************************/
369 /** Check that a given type is assignable to a given proto-type.
370 * If it is, return the type, otherwise return errType.
371 * @param pos Position to be used for error reporting.
372 * @param found The type that was found.
373 * @param req The type that was required.
374 */
375 Type checkType(DiagnosticPosition pos, Type found, Type req) {
376 if (req.tag == ERROR)
377 return req;
378 if (found.tag == FORALL)
379 return instantiatePoly(pos, (ForAll)found, req, convertWarner(pos, found, req));
380 if (req.tag == NONE)
381 return found;
382 if (types.isAssignable(found, req, convertWarner(pos, found, req)))
383 return found;
384 if (found.tag <= DOUBLE && req.tag <= DOUBLE)
385 return typeError(pos, diags.fragment("possible.loss.of.precision"), found, req);
386 if (found.isSuperBound()) {
387 log.error(pos, "assignment.from.super-bound", found);
388 return types.createErrorType(found);
389 }
390 if (req.isExtendsBound()) {
391 log.error(pos, "assignment.to.extends-bound", req);
392 return types.createErrorType(found);
393 }
394 return typeError(pos, diags.fragment("incompatible.types"), found, req);
395 }
397 /** Instantiate polymorphic type to some prototype, unless
398 * prototype is `anyPoly' in which case polymorphic type
399 * is returned unchanged.
400 */
401 Type instantiatePoly(DiagnosticPosition pos, ForAll t, Type pt, Warner warn) throws Infer.NoInstanceException {
402 if (pt == Infer.anyPoly && complexInference) {
403 return t;
404 } else if (pt == Infer.anyPoly || pt.tag == NONE) {
405 Type newpt = t.qtype.tag <= VOID ? t.qtype : syms.objectType;
406 return instantiatePoly(pos, t, newpt, warn);
407 } else if (pt.tag == ERROR) {
408 return pt;
409 } else {
410 try {
411 return infer.instantiateExpr(t, pt, warn);
412 } catch (Infer.NoInstanceException ex) {
413 if (ex.isAmbiguous) {
414 JCDiagnostic d = ex.getDiagnostic();
415 log.error(pos,
416 "undetermined.type" + (d!=null ? ".1" : ""),
417 t, d);
418 return types.createErrorType(pt);
419 } else {
420 JCDiagnostic d = ex.getDiagnostic();
421 return typeError(pos,
422 diags.fragment("incompatible.types" + (d!=null ? ".1" : ""), d),
423 t, pt);
424 }
425 } catch (Infer.InvalidInstanceException ex) {
426 JCDiagnostic d = ex.getDiagnostic();
427 log.error(pos, "invalid.inferred.types", t.tvars, d);
428 return types.createErrorType(pt);
429 }
430 }
431 }
433 /** Check that a given type can be cast to a given target type.
434 * Return the result of the cast.
435 * @param pos Position to be used for error reporting.
436 * @param found The type that is being cast.
437 * @param req The target type of the cast.
438 */
439 Type checkCastable(DiagnosticPosition pos, Type found, Type req) {
440 if (found.tag == FORALL) {
441 instantiatePoly(pos, (ForAll) found, req, castWarner(pos, found, req));
442 return req;
443 } else if (types.isCastable(found, req, castWarner(pos, found, req))) {
444 return req;
445 } else {
446 return typeError(pos,
447 diags.fragment("inconvertible.types"),
448 found, req);
449 }
450 }
451 //where
452 /** Is type a type variable, or a (possibly multi-dimensional) array of
453 * type variables?
454 */
455 boolean isTypeVar(Type t) {
456 return t.tag == TYPEVAR || t.tag == ARRAY && isTypeVar(types.elemtype(t));
457 }
459 /** Check that a type is within some bounds.
460 *
461 * Used in TypeApply to verify that, e.g., X in V<X> is a valid
462 * type argument.
463 * @param pos Position to be used for error reporting.
464 * @param a The type that should be bounded by bs.
465 * @param bs The bound.
466 */
467 private void checkExtends(DiagnosticPosition pos, Type a, TypeVar bs) {
468 if (a.isUnbound()) {
469 return;
470 } else if (a.tag != WILDCARD) {
471 a = types.upperBound(a);
472 for (List<Type> l = types.getBounds(bs); l.nonEmpty(); l = l.tail) {
473 if (!types.isSubtype(a, l.head)) {
474 log.error(pos, "not.within.bounds", a);
475 return;
476 }
477 }
478 } else if (a.isExtendsBound()) {
479 if (!types.isCastable(bs.getUpperBound(), types.upperBound(a), Warner.noWarnings))
480 log.error(pos, "not.within.bounds", a);
481 } else if (a.isSuperBound()) {
482 if (types.notSoftSubtype(types.lowerBound(a), bs.getUpperBound()))
483 log.error(pos, "not.within.bounds", a);
484 }
485 }
487 /** Check that a type is within some bounds.
488 *
489 * Used in TypeApply to verify that, e.g., X in V<X> is a valid
490 * type argument.
491 * @param pos Position to be used for error reporting.
492 * @param a The type that should be bounded by bs.
493 * @param bs The bound.
494 */
495 private void checkCapture(JCTypeApply tree) {
496 List<JCExpression> args = tree.getTypeArguments();
497 for (Type arg : types.capture(tree.type).getTypeArguments()) {
498 if (arg.tag == TYPEVAR && arg.getUpperBound().isErroneous()) {
499 log.error(args.head.pos, "not.within.bounds", args.head.type);
500 break;
501 }
502 args = args.tail;
503 }
504 }
506 /** Check that type is different from 'void'.
507 * @param pos Position to be used for error reporting.
508 * @param t The type to be checked.
509 */
510 Type checkNonVoid(DiagnosticPosition pos, Type t) {
511 if (t.tag == VOID) {
512 log.error(pos, "void.not.allowed.here");
513 return types.createErrorType(t);
514 } else {
515 return t;
516 }
517 }
519 /** Check that type is a class or interface type.
520 * @param pos Position to be used for error reporting.
521 * @param t The type to be checked.
522 */
523 Type checkClassType(DiagnosticPosition pos, Type t) {
524 if (t.tag != CLASS && t.tag != ERROR)
525 return typeTagError(pos,
526 diags.fragment("type.req.class"),
527 (t.tag == TYPEVAR)
528 ? diags.fragment("type.parameter", t)
529 : t);
530 else
531 return t;
532 }
534 /** Check that type is a class or interface type.
535 * @param pos Position to be used for error reporting.
536 * @param t The type to be checked.
537 * @param noBounds True if type bounds are illegal here.
538 */
539 Type checkClassType(DiagnosticPosition pos, Type t, boolean noBounds) {
540 t = checkClassType(pos, t);
541 if (noBounds && t.isParameterized()) {
542 List<Type> args = t.getTypeArguments();
543 while (args.nonEmpty()) {
544 if (args.head.tag == WILDCARD)
545 return typeTagError(pos,
546 Log.getLocalizedString("type.req.exact"),
547 args.head);
548 args = args.tail;
549 }
550 }
551 return t;
552 }
554 /** Check that type is a reifiable class, interface or array type.
555 * @param pos Position to be used for error reporting.
556 * @param t The type to be checked.
557 */
558 Type checkReifiableReferenceType(DiagnosticPosition pos, Type t) {
559 if (t.tag != CLASS && t.tag != ARRAY && t.tag != ERROR) {
560 return typeTagError(pos,
561 diags.fragment("type.req.class.array"),
562 t);
563 } else if (!types.isReifiable(t)) {
564 log.error(pos, "illegal.generic.type.for.instof");
565 return types.createErrorType(t);
566 } else {
567 return t;
568 }
569 }
571 /** Check that type is a reference type, i.e. a class, interface or array type
572 * or a type variable.
573 * @param pos Position to be used for error reporting.
574 * @param t The type to be checked.
575 */
576 Type checkRefType(DiagnosticPosition pos, Type t) {
577 switch (t.tag) {
578 case CLASS:
579 case ARRAY:
580 case TYPEVAR:
581 case WILDCARD:
582 case ERROR:
583 return t;
584 default:
585 return typeTagError(pos,
586 diags.fragment("type.req.ref"),
587 t);
588 }
589 }
591 /** Check that each type is a reference type, i.e. a class, interface or array type
592 * or a type variable.
593 * @param trees Original trees, used for error reporting.
594 * @param types The types to be checked.
595 */
596 List<Type> checkRefTypes(List<JCExpression> trees, List<Type> types) {
597 List<JCExpression> tl = trees;
598 for (List<Type> l = types; l.nonEmpty(); l = l.tail) {
599 l.head = checkRefType(tl.head.pos(), l.head);
600 tl = tl.tail;
601 }
602 return types;
603 }
605 /** Check that type is a null or reference type.
606 * @param pos Position to be used for error reporting.
607 * @param t The type to be checked.
608 */
609 Type checkNullOrRefType(DiagnosticPosition pos, Type t) {
610 switch (t.tag) {
611 case CLASS:
612 case ARRAY:
613 case TYPEVAR:
614 case WILDCARD:
615 case BOT:
616 case ERROR:
617 return t;
618 default:
619 return typeTagError(pos,
620 diags.fragment("type.req.ref"),
621 t);
622 }
623 }
625 /** Check that flag set does not contain elements of two conflicting sets. s
626 * Return true if it doesn't.
627 * @param pos Position to be used for error reporting.
628 * @param flags The set of flags to be checked.
629 * @param set1 Conflicting flags set #1.
630 * @param set2 Conflicting flags set #2.
631 */
632 boolean checkDisjoint(DiagnosticPosition pos, long flags, long set1, long set2) {
633 if ((flags & set1) != 0 && (flags & set2) != 0) {
634 log.error(pos,
635 "illegal.combination.of.modifiers",
636 asFlagSet(TreeInfo.firstFlag(flags & set1)),
637 asFlagSet(TreeInfo.firstFlag(flags & set2)));
638 return false;
639 } else
640 return true;
641 }
643 /** Check that given modifiers are legal for given symbol and
644 * return modifiers together with any implicit modififiers for that symbol.
645 * Warning: we can't use flags() here since this method
646 * is called during class enter, when flags() would cause a premature
647 * completion.
648 * @param pos Position to be used for error reporting.
649 * @param flags The set of modifiers given in a definition.
650 * @param sym The defined symbol.
651 */
652 long checkFlags(DiagnosticPosition pos, long flags, Symbol sym, JCTree tree) {
653 long mask;
654 long implicit = 0;
655 switch (sym.kind) {
656 case VAR:
657 if (sym.owner.kind != TYP)
658 mask = LocalVarFlags;
659 else if ((sym.owner.flags_field & INTERFACE) != 0)
660 mask = implicit = InterfaceVarFlags;
661 else
662 mask = VarFlags;
663 break;
664 case MTH:
665 if (sym.name == names.init) {
666 if ((sym.owner.flags_field & ENUM) != 0) {
667 // enum constructors cannot be declared public or
668 // protected and must be implicitly or explicitly
669 // private
670 implicit = PRIVATE;
671 mask = PRIVATE;
672 } else
673 mask = ConstructorFlags;
674 } else if ((sym.owner.flags_field & INTERFACE) != 0)
675 mask = implicit = InterfaceMethodFlags;
676 else {
677 mask = MethodFlags;
678 }
679 // Imply STRICTFP if owner has STRICTFP set.
680 if (((flags|implicit) & Flags.ABSTRACT) == 0)
681 implicit |= sym.owner.flags_field & STRICTFP;
682 break;
683 case TYP:
684 if (sym.isLocal()) {
685 mask = LocalClassFlags;
686 if (sym.name.isEmpty()) { // Anonymous class
687 // Anonymous classes in static methods are themselves static;
688 // that's why we admit STATIC here.
689 mask |= STATIC;
690 // JLS: Anonymous classes are final.
691 implicit |= FINAL;
692 }
693 if ((sym.owner.flags_field & STATIC) == 0 &&
694 (flags & ENUM) != 0)
695 log.error(pos, "enums.must.be.static");
696 } else if (sym.owner.kind == TYP) {
697 mask = MemberClassFlags;
698 if (sym.owner.owner.kind == PCK ||
699 (sym.owner.flags_field & STATIC) != 0)
700 mask |= STATIC;
701 else if ((flags & ENUM) != 0)
702 log.error(pos, "enums.must.be.static");
703 // Nested interfaces and enums are always STATIC (Spec ???)
704 if ((flags & (INTERFACE | ENUM)) != 0 ) implicit = STATIC;
705 } else {
706 mask = ClassFlags;
707 }
708 // Interfaces are always ABSTRACT
709 if ((flags & INTERFACE) != 0) implicit |= ABSTRACT;
711 if ((flags & ENUM) != 0) {
712 // enums can't be declared abstract or final
713 mask &= ~(ABSTRACT | FINAL);
714 implicit |= implicitEnumFinalFlag(tree);
715 }
716 // Imply STRICTFP if owner has STRICTFP set.
717 implicit |= sym.owner.flags_field & STRICTFP;
718 break;
719 default:
720 throw new AssertionError();
721 }
722 long illegal = flags & StandardFlags & ~mask;
723 if (illegal != 0) {
724 if ((illegal & INTERFACE) != 0) {
725 log.error(pos, "intf.not.allowed.here");
726 mask |= INTERFACE;
727 }
728 else {
729 log.error(pos,
730 "mod.not.allowed.here", asFlagSet(illegal));
731 }
732 }
733 else if ((sym.kind == TYP ||
734 // ISSUE: Disallowing abstract&private is no longer appropriate
735 // in the presence of inner classes. Should it be deleted here?
736 checkDisjoint(pos, flags,
737 ABSTRACT,
738 PRIVATE | STATIC))
739 &&
740 checkDisjoint(pos, flags,
741 ABSTRACT | INTERFACE,
742 FINAL | NATIVE | SYNCHRONIZED)
743 &&
744 checkDisjoint(pos, flags,
745 PUBLIC,
746 PRIVATE | PROTECTED)
747 &&
748 checkDisjoint(pos, flags,
749 PRIVATE,
750 PUBLIC | PROTECTED)
751 &&
752 checkDisjoint(pos, flags,
753 FINAL,
754 VOLATILE)
755 &&
756 (sym.kind == TYP ||
757 checkDisjoint(pos, flags,
758 ABSTRACT | NATIVE,
759 STRICTFP))) {
760 // skip
761 }
762 return flags & (mask | ~StandardFlags) | implicit;
763 }
766 /** Determine if this enum should be implicitly final.
767 *
768 * If the enum has no specialized enum contants, it is final.
769 *
770 * If the enum does have specialized enum contants, it is
771 * <i>not</i> final.
772 */
773 private long implicitEnumFinalFlag(JCTree tree) {
774 if (tree.getTag() != JCTree.CLASSDEF) return 0;
775 class SpecialTreeVisitor extends JCTree.Visitor {
776 boolean specialized;
777 SpecialTreeVisitor() {
778 this.specialized = false;
779 };
781 @Override
782 public void visitTree(JCTree tree) { /* no-op */ }
784 @Override
785 public void visitVarDef(JCVariableDecl tree) {
786 if ((tree.mods.flags & ENUM) != 0) {
787 if (tree.init instanceof JCNewClass &&
788 ((JCNewClass) tree.init).def != null) {
789 specialized = true;
790 }
791 }
792 }
793 }
795 SpecialTreeVisitor sts = new SpecialTreeVisitor();
796 JCClassDecl cdef = (JCClassDecl) tree;
797 for (JCTree defs: cdef.defs) {
798 defs.accept(sts);
799 if (sts.specialized) return 0;
800 }
801 return FINAL;
802 }
804 /* *************************************************************************
805 * Type Validation
806 **************************************************************************/
808 /** Validate a type expression. That is,
809 * check that all type arguments of a parametric type are within
810 * their bounds. This must be done in a second phase after type attributon
811 * since a class might have a subclass as type parameter bound. E.g:
812 *
813 * class B<A extends C> { ... }
814 * class C extends B<C> { ... }
815 *
816 * and we can't make sure that the bound is already attributed because
817 * of possible cycles.
818 */
819 private Validator validator = new Validator();
821 /** Visitor method: Validate a type expression, if it is not null, catching
822 * and reporting any completion failures.
823 */
824 void validate(JCTree tree, Env<AttrContext> env) {
825 try {
826 if (tree != null) {
827 validator.env = env;
828 tree.accept(validator);
829 checkRaw(tree, env);
830 }
831 } catch (CompletionFailure ex) {
832 completionError(tree.pos(), ex);
833 }
834 }
835 //where
836 void checkRaw(JCTree tree, Env<AttrContext> env) {
837 if (lint.isEnabled(Lint.LintCategory.RAW) &&
838 tree.type.tag == CLASS &&
839 !env.enclClass.name.isEmpty() && //anonymous or intersection
840 tree.type.isRaw()) {
841 log.warning(tree.pos(), "raw.class.use", tree.type, tree.type.tsym.type);
842 }
843 }
845 /** Visitor method: Validate a list of type expressions.
846 */
847 void validate(List<? extends JCTree> trees, Env<AttrContext> env) {
848 for (List<? extends JCTree> l = trees; l.nonEmpty(); l = l.tail)
849 validate(l.head, env);
850 }
852 /** A visitor class for type validation.
853 */
854 class Validator extends JCTree.Visitor {
856 @Override
857 public void visitTypeArray(JCArrayTypeTree tree) {
858 validate(tree.elemtype, env);
859 }
861 @Override
862 public void visitTypeApply(JCTypeApply tree) {
863 if (tree.type.tag == CLASS) {
864 List<Type> formals = tree.type.tsym.type.allparams();
865 List<Type> actuals = tree.type.allparams();
866 List<JCExpression> args = tree.arguments;
867 List<Type> forms = tree.type.tsym.type.getTypeArguments();
868 ListBuffer<TypeVar> tvars_buf = new ListBuffer<TypeVar>();
870 // For matching pairs of actual argument types `a' and
871 // formal type parameters with declared bound `b' ...
872 while (args.nonEmpty() && forms.nonEmpty()) {
873 validate(args.head, env);
875 // exact type arguments needs to know their
876 // bounds (for upper and lower bound
877 // calculations). So we create new TypeVars with
878 // bounds substed with actuals.
879 tvars_buf.append(types.substBound(((TypeVar)forms.head),
880 formals,
881 actuals));
883 args = args.tail;
884 forms = forms.tail;
885 }
887 args = tree.arguments;
888 List<Type> tvars_cap = types.substBounds(formals,
889 formals,
890 types.capture(tree.type).allparams());
891 while (args.nonEmpty() && tvars_cap.nonEmpty()) {
892 // Let the actual arguments know their bound
893 args.head.type.withTypeVar((TypeVar)tvars_cap.head);
894 args = args.tail;
895 tvars_cap = tvars_cap.tail;
896 }
898 args = tree.arguments;
899 List<TypeVar> tvars = tvars_buf.toList();
901 while (args.nonEmpty() && tvars.nonEmpty()) {
902 checkExtends(args.head.pos(),
903 args.head.type,
904 tvars.head);
905 args = args.tail;
906 tvars = tvars.tail;
907 }
909 checkCapture(tree);
911 // Check that this type is either fully parameterized, or
912 // not parameterized at all.
913 if (tree.type.getEnclosingType().isRaw())
914 log.error(tree.pos(), "improperly.formed.type.inner.raw.param");
915 if (tree.clazz.getTag() == JCTree.SELECT)
916 visitSelectInternal((JCFieldAccess)tree.clazz);
917 }
918 }
920 @Override
921 public void visitTypeParameter(JCTypeParameter tree) {
922 validate(tree.bounds, env);
923 checkClassBounds(tree.pos(), tree.type);
924 }
926 @Override
927 public void visitWildcard(JCWildcard tree) {
928 if (tree.inner != null)
929 validate(tree.inner, env);
930 }
932 @Override
933 public void visitSelect(JCFieldAccess tree) {
934 if (tree.type.tag == CLASS) {
935 visitSelectInternal(tree);
937 // Check that this type is either fully parameterized, or
938 // not parameterized at all.
939 if (tree.selected.type.isParameterized() && tree.type.tsym.type.getTypeArguments().nonEmpty())
940 log.error(tree.pos(), "improperly.formed.type.param.missing");
941 }
942 }
943 public void visitSelectInternal(JCFieldAccess tree) {
944 if (tree.type.tsym.isStatic() &&
945 tree.selected.type.isParameterized()) {
946 // The enclosing type is not a class, so we are
947 // looking at a static member type. However, the
948 // qualifying expression is parameterized.
949 log.error(tree.pos(), "cant.select.static.class.from.param.type");
950 } else {
951 // otherwise validate the rest of the expression
952 tree.selected.accept(this);
953 }
954 }
956 @Override
957 public void visitAnnotatedType(JCAnnotatedType tree) {
958 tree.underlyingType.accept(this);
959 }
961 /** Default visitor method: do nothing.
962 */
963 @Override
964 public void visitTree(JCTree tree) {
965 }
967 Env<AttrContext> env;
968 }
970 /* *************************************************************************
971 * Exception checking
972 **************************************************************************/
974 /* The following methods treat classes as sets that contain
975 * the class itself and all their subclasses
976 */
978 /** Is given type a subtype of some of the types in given list?
979 */
980 boolean subset(Type t, List<Type> ts) {
981 for (List<Type> l = ts; l.nonEmpty(); l = l.tail)
982 if (types.isSubtype(t, l.head)) return true;
983 return false;
984 }
986 /** Is given type a subtype or supertype of
987 * some of the types in given list?
988 */
989 boolean intersects(Type t, List<Type> ts) {
990 for (List<Type> l = ts; l.nonEmpty(); l = l.tail)
991 if (types.isSubtype(t, l.head) || types.isSubtype(l.head, t)) return true;
992 return false;
993 }
995 /** Add type set to given type list, unless it is a subclass of some class
996 * in the list.
997 */
998 List<Type> incl(Type t, List<Type> ts) {
999 return subset(t, ts) ? ts : excl(t, ts).prepend(t);
1000 }
1002 /** Remove type set from type set list.
1003 */
1004 List<Type> excl(Type t, List<Type> ts) {
1005 if (ts.isEmpty()) {
1006 return ts;
1007 } else {
1008 List<Type> ts1 = excl(t, ts.tail);
1009 if (types.isSubtype(ts.head, t)) return ts1;
1010 else if (ts1 == ts.tail) return ts;
1011 else return ts1.prepend(ts.head);
1012 }
1013 }
1015 /** Form the union of two type set lists.
1016 */
1017 List<Type> union(List<Type> ts1, List<Type> ts2) {
1018 List<Type> ts = ts1;
1019 for (List<Type> l = ts2; l.nonEmpty(); l = l.tail)
1020 ts = incl(l.head, ts);
1021 return ts;
1022 }
1024 /** Form the difference of two type lists.
1025 */
1026 List<Type> diff(List<Type> ts1, List<Type> ts2) {
1027 List<Type> ts = ts1;
1028 for (List<Type> l = ts2; l.nonEmpty(); l = l.tail)
1029 ts = excl(l.head, ts);
1030 return ts;
1031 }
1033 /** Form the intersection of two type lists.
1034 */
1035 public List<Type> intersect(List<Type> ts1, List<Type> ts2) {
1036 List<Type> ts = List.nil();
1037 for (List<Type> l = ts1; l.nonEmpty(); l = l.tail)
1038 if (subset(l.head, ts2)) ts = incl(l.head, ts);
1039 for (List<Type> l = ts2; l.nonEmpty(); l = l.tail)
1040 if (subset(l.head, ts1)) ts = incl(l.head, ts);
1041 return ts;
1042 }
1044 /** Is exc an exception symbol that need not be declared?
1045 */
1046 boolean isUnchecked(ClassSymbol exc) {
1047 return
1048 exc.kind == ERR ||
1049 exc.isSubClass(syms.errorType.tsym, types) ||
1050 exc.isSubClass(syms.runtimeExceptionType.tsym, types);
1051 }
1053 /** Is exc an exception type that need not be declared?
1054 */
1055 boolean isUnchecked(Type exc) {
1056 return
1057 (exc.tag == TYPEVAR) ? isUnchecked(types.supertype(exc)) :
1058 (exc.tag == CLASS) ? isUnchecked((ClassSymbol)exc.tsym) :
1059 exc.tag == BOT;
1060 }
1062 /** Same, but handling completion failures.
1063 */
1064 boolean isUnchecked(DiagnosticPosition pos, Type exc) {
1065 try {
1066 return isUnchecked(exc);
1067 } catch (CompletionFailure ex) {
1068 completionError(pos, ex);
1069 return true;
1070 }
1071 }
1073 /** Is exc handled by given exception list?
1074 */
1075 boolean isHandled(Type exc, List<Type> handled) {
1076 return isUnchecked(exc) || subset(exc, handled);
1077 }
1079 /** Return all exceptions in thrown list that are not in handled list.
1080 * @param thrown The list of thrown exceptions.
1081 * @param handled The list of handled exceptions.
1082 */
1083 List<Type> unhandled(List<Type> thrown, List<Type> handled) {
1084 List<Type> unhandled = List.nil();
1085 for (List<Type> l = thrown; l.nonEmpty(); l = l.tail)
1086 if (!isHandled(l.head, handled)) unhandled = unhandled.prepend(l.head);
1087 return unhandled;
1088 }
1090 /* *************************************************************************
1091 * Overriding/Implementation checking
1092 **************************************************************************/
1094 /** The level of access protection given by a flag set,
1095 * where PRIVATE is highest and PUBLIC is lowest.
1096 */
1097 static int protection(long flags) {
1098 switch ((short)(flags & AccessFlags)) {
1099 case PRIVATE: return 3;
1100 case PROTECTED: return 1;
1101 default:
1102 case PUBLIC: return 0;
1103 case 0: return 2;
1104 }
1105 }
1107 /** A customized "cannot override" error message.
1108 * @param m The overriding method.
1109 * @param other The overridden method.
1110 * @return An internationalized string.
1111 */
1112 Object cannotOverride(MethodSymbol m, MethodSymbol other) {
1113 String key;
1114 if ((other.owner.flags() & INTERFACE) == 0)
1115 key = "cant.override";
1116 else if ((m.owner.flags() & INTERFACE) == 0)
1117 key = "cant.implement";
1118 else
1119 key = "clashes.with";
1120 return diags.fragment(key, m, m.location(), other, other.location());
1121 }
1123 /** A customized "override" warning message.
1124 * @param m The overriding method.
1125 * @param other The overridden method.
1126 * @return An internationalized string.
1127 */
1128 Object uncheckedOverrides(MethodSymbol m, MethodSymbol other) {
1129 String key;
1130 if ((other.owner.flags() & INTERFACE) == 0)
1131 key = "unchecked.override";
1132 else if ((m.owner.flags() & INTERFACE) == 0)
1133 key = "unchecked.implement";
1134 else
1135 key = "unchecked.clash.with";
1136 return diags.fragment(key, m, m.location(), other, other.location());
1137 }
1139 /** A customized "override" warning message.
1140 * @param m The overriding method.
1141 * @param other The overridden method.
1142 * @return An internationalized string.
1143 */
1144 Object varargsOverrides(MethodSymbol m, MethodSymbol other) {
1145 String key;
1146 if ((other.owner.flags() & INTERFACE) == 0)
1147 key = "varargs.override";
1148 else if ((m.owner.flags() & INTERFACE) == 0)
1149 key = "varargs.implement";
1150 else
1151 key = "varargs.clash.with";
1152 return diags.fragment(key, m, m.location(), other, other.location());
1153 }
1155 /** Check that this method conforms with overridden method 'other'.
1156 * where `origin' is the class where checking started.
1157 * Complications:
1158 * (1) Do not check overriding of synthetic methods
1159 * (reason: they might be final).
1160 * todo: check whether this is still necessary.
1161 * (2) Admit the case where an interface proxy throws fewer exceptions
1162 * than the method it implements. Augment the proxy methods with the
1163 * undeclared exceptions in this case.
1164 * (3) When generics are enabled, admit the case where an interface proxy
1165 * has a result type
1166 * extended by the result type of the method it implements.
1167 * Change the proxies result type to the smaller type in this case.
1168 *
1169 * @param tree The tree from which positions
1170 * are extracted for errors.
1171 * @param m The overriding method.
1172 * @param other The overridden method.
1173 * @param origin The class of which the overriding method
1174 * is a member.
1175 */
1176 void checkOverride(JCTree tree,
1177 MethodSymbol m,
1178 MethodSymbol other,
1179 ClassSymbol origin) {
1180 // Don't check overriding of synthetic methods or by bridge methods.
1181 if ((m.flags() & (SYNTHETIC|BRIDGE)) != 0 || (other.flags() & SYNTHETIC) != 0) {
1182 return;
1183 }
1185 // Error if static method overrides instance method (JLS 8.4.6.2).
1186 if ((m.flags() & STATIC) != 0 &&
1187 (other.flags() & STATIC) == 0) {
1188 log.error(TreeInfo.diagnosticPositionFor(m, tree), "override.static",
1189 cannotOverride(m, other));
1190 return;
1191 }
1193 // Error if instance method overrides static or final
1194 // method (JLS 8.4.6.1).
1195 if ((other.flags() & FINAL) != 0 ||
1196 (m.flags() & STATIC) == 0 &&
1197 (other.flags() & STATIC) != 0) {
1198 log.error(TreeInfo.diagnosticPositionFor(m, tree), "override.meth",
1199 cannotOverride(m, other),
1200 asFlagSet(other.flags() & (FINAL | STATIC)));
1201 return;
1202 }
1204 if ((m.owner.flags() & ANNOTATION) != 0) {
1205 // handled in validateAnnotationMethod
1206 return;
1207 }
1209 // Error if overriding method has weaker access (JLS 8.4.6.3).
1210 if ((origin.flags() & INTERFACE) == 0 &&
1211 protection(m.flags()) > protection(other.flags())) {
1212 log.error(TreeInfo.diagnosticPositionFor(m, tree), "override.weaker.access",
1213 cannotOverride(m, other),
1214 other.flags() == 0 ?
1215 Flag.PACKAGE :
1216 asFlagSet(other.flags() & AccessFlags));
1217 return;
1218 }
1220 Type mt = types.memberType(origin.type, m);
1221 Type ot = types.memberType(origin.type, other);
1222 // Error if overriding result type is different
1223 // (or, in the case of generics mode, not a subtype) of
1224 // overridden result type. We have to rename any type parameters
1225 // before comparing types.
1226 List<Type> mtvars = mt.getTypeArguments();
1227 List<Type> otvars = ot.getTypeArguments();
1228 Type mtres = mt.getReturnType();
1229 Type otres = types.subst(ot.getReturnType(), otvars, mtvars);
1231 overrideWarner.warned = false;
1232 boolean resultTypesOK =
1233 types.returnTypeSubstitutable(mt, ot, otres, overrideWarner);
1234 if (!resultTypesOK) {
1235 if (!allowCovariantReturns &&
1236 m.owner != origin &&
1237 m.owner.isSubClass(other.owner, types)) {
1238 // allow limited interoperability with covariant returns
1239 } else {
1240 log.error(TreeInfo.diagnosticPositionFor(m, tree),
1241 "override.incompatible.ret",
1242 cannotOverride(m, other),
1243 mtres, otres);
1244 return;
1245 }
1246 } else if (overrideWarner.warned) {
1247 warnUnchecked(TreeInfo.diagnosticPositionFor(m, tree),
1248 "override.unchecked.ret",
1249 uncheckedOverrides(m, other),
1250 mtres, otres);
1251 }
1253 // Error if overriding method throws an exception not reported
1254 // by overridden method.
1255 List<Type> otthrown = types.subst(ot.getThrownTypes(), otvars, mtvars);
1256 List<Type> unhandledErased = unhandled(mt.getThrownTypes(), types.erasure(otthrown));
1257 List<Type> unhandledUnerased = unhandled(mt.getThrownTypes(), otthrown);
1258 if (unhandledErased.nonEmpty()) {
1259 log.error(TreeInfo.diagnosticPositionFor(m, tree),
1260 "override.meth.doesnt.throw",
1261 cannotOverride(m, other),
1262 unhandledUnerased.head);
1263 return;
1264 }
1265 else if (unhandledUnerased.nonEmpty()) {
1266 warnUnchecked(TreeInfo.diagnosticPositionFor(m, tree),
1267 "override.unchecked.thrown",
1268 cannotOverride(m, other),
1269 unhandledUnerased.head);
1270 return;
1271 }
1273 // Optional warning if varargs don't agree
1274 if ((((m.flags() ^ other.flags()) & Flags.VARARGS) != 0)
1275 && lint.isEnabled(Lint.LintCategory.OVERRIDES)) {
1276 log.warning(TreeInfo.diagnosticPositionFor(m, tree),
1277 ((m.flags() & Flags.VARARGS) != 0)
1278 ? "override.varargs.missing"
1279 : "override.varargs.extra",
1280 varargsOverrides(m, other));
1281 }
1283 // Warn if instance method overrides bridge method (compiler spec ??)
1284 if ((other.flags() & BRIDGE) != 0) {
1285 log.warning(TreeInfo.diagnosticPositionFor(m, tree), "override.bridge",
1286 uncheckedOverrides(m, other));
1287 }
1289 // Warn if a deprecated method overridden by a non-deprecated one.
1290 if ((other.flags() & DEPRECATED) != 0
1291 && (m.flags() & DEPRECATED) == 0
1292 && m.outermostClass() != other.outermostClass()
1293 && !isDeprecatedOverrideIgnorable(other, origin)) {
1294 warnDeprecated(TreeInfo.diagnosticPositionFor(m, tree), other);
1295 }
1296 }
1297 // where
1298 private boolean isDeprecatedOverrideIgnorable(MethodSymbol m, ClassSymbol origin) {
1299 // If the method, m, is defined in an interface, then ignore the issue if the method
1300 // is only inherited via a supertype and also implemented in the supertype,
1301 // because in that case, we will rediscover the issue when examining the method
1302 // in the supertype.
1303 // If the method, m, is not defined in an interface, then the only time we need to
1304 // address the issue is when the method is the supertype implemementation: any other
1305 // case, we will have dealt with when examining the supertype classes
1306 ClassSymbol mc = m.enclClass();
1307 Type st = types.supertype(origin.type);
1308 if (st.tag != CLASS)
1309 return true;
1310 MethodSymbol stimpl = m.implementation((ClassSymbol)st.tsym, types, false);
1312 if (mc != null && ((mc.flags() & INTERFACE) != 0)) {
1313 List<Type> intfs = types.interfaces(origin.type);
1314 return (intfs.contains(mc.type) ? false : (stimpl != null));
1315 }
1316 else
1317 return (stimpl != m);
1318 }
1321 // used to check if there were any unchecked conversions
1322 Warner overrideWarner = new Warner();
1324 /** Check that a class does not inherit two concrete methods
1325 * with the same signature.
1326 * @param pos Position to be used for error reporting.
1327 * @param site The class type to be checked.
1328 */
1329 public void checkCompatibleConcretes(DiagnosticPosition pos, Type site) {
1330 Type sup = types.supertype(site);
1331 if (sup.tag != CLASS) return;
1333 for (Type t1 = sup;
1334 t1.tsym.type.isParameterized();
1335 t1 = types.supertype(t1)) {
1336 for (Scope.Entry e1 = t1.tsym.members().elems;
1337 e1 != null;
1338 e1 = e1.sibling) {
1339 Symbol s1 = e1.sym;
1340 if (s1.kind != MTH ||
1341 (s1.flags() & (STATIC|SYNTHETIC|BRIDGE)) != 0 ||
1342 !s1.isInheritedIn(site.tsym, types) ||
1343 ((MethodSymbol)s1).implementation(site.tsym,
1344 types,
1345 true) != s1)
1346 continue;
1347 Type st1 = types.memberType(t1, s1);
1348 int s1ArgsLength = st1.getParameterTypes().length();
1349 if (st1 == s1.type) continue;
1351 for (Type t2 = sup;
1352 t2.tag == CLASS;
1353 t2 = types.supertype(t2)) {
1354 for (Scope.Entry e2 = t2.tsym.members().lookup(s1.name);
1355 e2.scope != null;
1356 e2 = e2.next()) {
1357 Symbol s2 = e2.sym;
1358 if (s2 == s1 ||
1359 s2.kind != MTH ||
1360 (s2.flags() & (STATIC|SYNTHETIC|BRIDGE)) != 0 ||
1361 s2.type.getParameterTypes().length() != s1ArgsLength ||
1362 !s2.isInheritedIn(site.tsym, types) ||
1363 ((MethodSymbol)s2).implementation(site.tsym,
1364 types,
1365 true) != s2)
1366 continue;
1367 Type st2 = types.memberType(t2, s2);
1368 if (types.overrideEquivalent(st1, st2))
1369 log.error(pos, "concrete.inheritance.conflict",
1370 s1, t1, s2, t2, sup);
1371 }
1372 }
1373 }
1374 }
1375 }
1377 /** Check that classes (or interfaces) do not each define an abstract
1378 * method with same name and arguments but incompatible return types.
1379 * @param pos Position to be used for error reporting.
1380 * @param t1 The first argument type.
1381 * @param t2 The second argument type.
1382 */
1383 public boolean checkCompatibleAbstracts(DiagnosticPosition pos,
1384 Type t1,
1385 Type t2) {
1386 return checkCompatibleAbstracts(pos, t1, t2,
1387 types.makeCompoundType(t1, t2));
1388 }
1390 public boolean checkCompatibleAbstracts(DiagnosticPosition pos,
1391 Type t1,
1392 Type t2,
1393 Type site) {
1394 Symbol sym = firstIncompatibility(t1, t2, site);
1395 if (sym != null) {
1396 log.error(pos, "types.incompatible.diff.ret",
1397 t1, t2, sym.name +
1398 "(" + types.memberType(t2, sym).getParameterTypes() + ")");
1399 return false;
1400 }
1401 return true;
1402 }
1404 /** Return the first method which is defined with same args
1405 * but different return types in two given interfaces, or null if none
1406 * exists.
1407 * @param t1 The first type.
1408 * @param t2 The second type.
1409 * @param site The most derived type.
1410 * @returns symbol from t2 that conflicts with one in t1.
1411 */
1412 private Symbol firstIncompatibility(Type t1, Type t2, Type site) {
1413 Map<TypeSymbol,Type> interfaces1 = new HashMap<TypeSymbol,Type>();
1414 closure(t1, interfaces1);
1415 Map<TypeSymbol,Type> interfaces2;
1416 if (t1 == t2)
1417 interfaces2 = interfaces1;
1418 else
1419 closure(t2, interfaces1, interfaces2 = new HashMap<TypeSymbol,Type>());
1421 for (Type t3 : interfaces1.values()) {
1422 for (Type t4 : interfaces2.values()) {
1423 Symbol s = firstDirectIncompatibility(t3, t4, site);
1424 if (s != null) return s;
1425 }
1426 }
1427 return null;
1428 }
1430 /** Compute all the supertypes of t, indexed by type symbol. */
1431 private void closure(Type t, Map<TypeSymbol,Type> typeMap) {
1432 if (t.tag != CLASS) return;
1433 if (typeMap.put(t.tsym, t) == null) {
1434 closure(types.supertype(t), typeMap);
1435 for (Type i : types.interfaces(t))
1436 closure(i, typeMap);
1437 }
1438 }
1440 /** Compute all the supertypes of t, indexed by type symbol (except thise in typesSkip). */
1441 private void closure(Type t, Map<TypeSymbol,Type> typesSkip, Map<TypeSymbol,Type> typeMap) {
1442 if (t.tag != CLASS) return;
1443 if (typesSkip.get(t.tsym) != null) return;
1444 if (typeMap.put(t.tsym, t) == null) {
1445 closure(types.supertype(t), typesSkip, typeMap);
1446 for (Type i : types.interfaces(t))
1447 closure(i, typesSkip, typeMap);
1448 }
1449 }
1451 /** Return the first method in t2 that conflicts with a method from t1. */
1452 private Symbol firstDirectIncompatibility(Type t1, Type t2, Type site) {
1453 for (Scope.Entry e1 = t1.tsym.members().elems; e1 != null; e1 = e1.sibling) {
1454 Symbol s1 = e1.sym;
1455 Type st1 = null;
1456 if (s1.kind != MTH || !s1.isInheritedIn(site.tsym, types)) continue;
1457 Symbol impl = ((MethodSymbol)s1).implementation(site.tsym, types, false);
1458 if (impl != null && (impl.flags() & ABSTRACT) == 0) continue;
1459 for (Scope.Entry e2 = t2.tsym.members().lookup(s1.name); e2.scope != null; e2 = e2.next()) {
1460 Symbol s2 = e2.sym;
1461 if (s1 == s2) continue;
1462 if (s2.kind != MTH || !s2.isInheritedIn(site.tsym, types)) continue;
1463 if (st1 == null) st1 = types.memberType(t1, s1);
1464 Type st2 = types.memberType(t2, s2);
1465 if (types.overrideEquivalent(st1, st2)) {
1466 List<Type> tvars1 = st1.getTypeArguments();
1467 List<Type> tvars2 = st2.getTypeArguments();
1468 Type rt1 = st1.getReturnType();
1469 Type rt2 = types.subst(st2.getReturnType(), tvars2, tvars1);
1470 boolean compat =
1471 types.isSameType(rt1, rt2) ||
1472 rt1.tag >= CLASS && rt2.tag >= CLASS &&
1473 (types.covariantReturnType(rt1, rt2, Warner.noWarnings) ||
1474 types.covariantReturnType(rt2, rt1, Warner.noWarnings)) ||
1475 checkCommonOverriderIn(s1,s2,site);
1476 if (!compat) return s2;
1477 }
1478 }
1479 }
1480 return null;
1481 }
1482 //WHERE
1483 boolean checkCommonOverriderIn(Symbol s1, Symbol s2, Type site) {
1484 Map<TypeSymbol,Type> supertypes = new HashMap<TypeSymbol,Type>();
1485 Type st1 = types.memberType(site, s1);
1486 Type st2 = types.memberType(site, s2);
1487 closure(site, supertypes);
1488 for (Type t : supertypes.values()) {
1489 for (Scope.Entry e = t.tsym.members().lookup(s1.name); e.scope != null; e = e.next()) {
1490 Symbol s3 = e.sym;
1491 if (s3 == s1 || s3 == s2 || s3.kind != MTH || (s3.flags() & (BRIDGE|SYNTHETIC)) != 0) continue;
1492 Type st3 = types.memberType(site,s3);
1493 if (types.overrideEquivalent(st3, st1) && types.overrideEquivalent(st3, st2)) {
1494 if (s3.owner == site.tsym) {
1495 return true;
1496 }
1497 List<Type> tvars1 = st1.getTypeArguments();
1498 List<Type> tvars2 = st2.getTypeArguments();
1499 List<Type> tvars3 = st3.getTypeArguments();
1500 Type rt1 = st1.getReturnType();
1501 Type rt2 = st2.getReturnType();
1502 Type rt13 = types.subst(st3.getReturnType(), tvars3, tvars1);
1503 Type rt23 = types.subst(st3.getReturnType(), tvars3, tvars2);
1504 boolean compat =
1505 rt13.tag >= CLASS && rt23.tag >= CLASS &&
1506 (types.covariantReturnType(rt13, rt1, Warner.noWarnings) &&
1507 types.covariantReturnType(rt23, rt2, Warner.noWarnings));
1508 if (compat)
1509 return true;
1510 }
1511 }
1512 }
1513 return false;
1514 }
1516 /** Check that a given method conforms with any method it overrides.
1517 * @param tree The tree from which positions are extracted
1518 * for errors.
1519 * @param m The overriding method.
1520 */
1521 void checkOverride(JCTree tree, MethodSymbol m) {
1522 ClassSymbol origin = (ClassSymbol)m.owner;
1523 if ((origin.flags() & ENUM) != 0 && names.finalize.equals(m.name))
1524 if (m.overrides(syms.enumFinalFinalize, origin, types, false)) {
1525 log.error(tree.pos(), "enum.no.finalize");
1526 return;
1527 }
1528 for (Type t = types.supertype(origin.type); t.tag == CLASS;
1529 t = types.supertype(t)) {
1530 TypeSymbol c = t.tsym;
1531 Scope.Entry e = c.members().lookup(m.name);
1532 while (e.scope != null) {
1533 if (m.overrides(e.sym, origin, types, false))
1534 checkOverride(tree, m, (MethodSymbol)e.sym, origin);
1535 else if (e.sym.kind == MTH &&
1536 e.sym.isInheritedIn(origin, types) &&
1537 (e.sym.flags() & SYNTHETIC) == 0 &&
1538 !m.isConstructor()) {
1539 Type er1 = m.erasure(types);
1540 Type er2 = e.sym.erasure(types);
1541 if (types.isSameTypes(er1.getParameterTypes(),
1542 er2.getParameterTypes())) {
1543 log.error(TreeInfo.diagnosticPositionFor(m, tree),
1544 "name.clash.same.erasure.no.override",
1545 m, m.location(),
1546 e.sym, e.sym.location());
1547 }
1548 }
1549 e = e.next();
1550 }
1551 }
1552 }
1554 /** Check that all abstract members of given class have definitions.
1555 * @param pos Position to be used for error reporting.
1556 * @param c The class.
1557 */
1558 void checkAllDefined(DiagnosticPosition pos, ClassSymbol c) {
1559 try {
1560 MethodSymbol undef = firstUndef(c, c);
1561 if (undef != null) {
1562 if ((c.flags() & ENUM) != 0 &&
1563 types.supertype(c.type).tsym == syms.enumSym &&
1564 (c.flags() & FINAL) == 0) {
1565 // add the ABSTRACT flag to an enum
1566 c.flags_field |= ABSTRACT;
1567 } else {
1568 MethodSymbol undef1 =
1569 new MethodSymbol(undef.flags(), undef.name,
1570 types.memberType(c.type, undef), undef.owner);
1571 log.error(pos, "does.not.override.abstract",
1572 c, undef1, undef1.location());
1573 }
1574 }
1575 } catch (CompletionFailure ex) {
1576 completionError(pos, ex);
1577 }
1578 }
1579 //where
1580 /** Return first abstract member of class `c' that is not defined
1581 * in `impl', null if there is none.
1582 */
1583 private MethodSymbol firstUndef(ClassSymbol impl, ClassSymbol c) {
1584 MethodSymbol undef = null;
1585 // Do not bother to search in classes that are not abstract,
1586 // since they cannot have abstract members.
1587 if (c == impl || (c.flags() & (ABSTRACT | INTERFACE)) != 0) {
1588 Scope s = c.members();
1589 for (Scope.Entry e = s.elems;
1590 undef == null && e != null;
1591 e = e.sibling) {
1592 if (e.sym.kind == MTH &&
1593 (e.sym.flags() & (ABSTRACT|IPROXY)) == ABSTRACT) {
1594 MethodSymbol absmeth = (MethodSymbol)e.sym;
1595 MethodSymbol implmeth = absmeth.implementation(impl, types, true);
1596 if (implmeth == null || implmeth == absmeth)
1597 undef = absmeth;
1598 }
1599 }
1600 if (undef == null) {
1601 Type st = types.supertype(c.type);
1602 if (st.tag == CLASS)
1603 undef = firstUndef(impl, (ClassSymbol)st.tsym);
1604 }
1605 for (List<Type> l = types.interfaces(c.type);
1606 undef == null && l.nonEmpty();
1607 l = l.tail) {
1608 undef = firstUndef(impl, (ClassSymbol)l.head.tsym);
1609 }
1610 }
1611 return undef;
1612 }
1614 /** Check for cyclic references. Issue an error if the
1615 * symbol of the type referred to has a LOCKED flag set.
1616 *
1617 * @param pos Position to be used for error reporting.
1618 * @param t The type referred to.
1619 */
1620 void checkNonCyclic(DiagnosticPosition pos, Type t) {
1621 checkNonCyclicInternal(pos, t);
1622 }
1625 void checkNonCyclic(DiagnosticPosition pos, TypeVar t) {
1626 checkNonCyclic1(pos, t, List.<TypeVar>nil());
1627 }
1629 private void checkNonCyclic1(DiagnosticPosition pos, Type t, List<TypeVar> seen) {
1630 final TypeVar tv;
1631 if (t.tag == TYPEVAR && (t.tsym.flags() & UNATTRIBUTED) != 0)
1632 return;
1633 if (seen.contains(t)) {
1634 tv = (TypeVar)t;
1635 tv.bound = types.createErrorType(t);
1636 log.error(pos, "cyclic.inheritance", t);
1637 } else if (t.tag == TYPEVAR) {
1638 tv = (TypeVar)t;
1639 seen = seen.prepend(tv);
1640 for (Type b : types.getBounds(tv))
1641 checkNonCyclic1(pos, b, seen);
1642 }
1643 }
1645 /** Check for cyclic references. Issue an error if the
1646 * symbol of the type referred to has a LOCKED flag set.
1647 *
1648 * @param pos Position to be used for error reporting.
1649 * @param t The type referred to.
1650 * @returns True if the check completed on all attributed classes
1651 */
1652 private boolean checkNonCyclicInternal(DiagnosticPosition pos, Type t) {
1653 boolean complete = true; // was the check complete?
1654 //- System.err.println("checkNonCyclicInternal("+t+");");//DEBUG
1655 Symbol c = t.tsym;
1656 if ((c.flags_field & ACYCLIC) != 0) return true;
1658 if ((c.flags_field & LOCKED) != 0) {
1659 noteCyclic(pos, (ClassSymbol)c);
1660 } else if (!c.type.isErroneous()) {
1661 try {
1662 c.flags_field |= LOCKED;
1663 if (c.type.tag == CLASS) {
1664 ClassType clazz = (ClassType)c.type;
1665 if (clazz.interfaces_field != null)
1666 for (List<Type> l=clazz.interfaces_field; l.nonEmpty(); l=l.tail)
1667 complete &= checkNonCyclicInternal(pos, l.head);
1668 if (clazz.supertype_field != null) {
1669 Type st = clazz.supertype_field;
1670 if (st != null && st.tag == CLASS)
1671 complete &= checkNonCyclicInternal(pos, st);
1672 }
1673 if (c.owner.kind == TYP)
1674 complete &= checkNonCyclicInternal(pos, c.owner.type);
1675 }
1676 } finally {
1677 c.flags_field &= ~LOCKED;
1678 }
1679 }
1680 if (complete)
1681 complete = ((c.flags_field & UNATTRIBUTED) == 0) && c.completer == null;
1682 if (complete) c.flags_field |= ACYCLIC;
1683 return complete;
1684 }
1686 /** Note that we found an inheritance cycle. */
1687 private void noteCyclic(DiagnosticPosition pos, ClassSymbol c) {
1688 log.error(pos, "cyclic.inheritance", c);
1689 for (List<Type> l=types.interfaces(c.type); l.nonEmpty(); l=l.tail)
1690 l.head = types.createErrorType((ClassSymbol)l.head.tsym, Type.noType);
1691 Type st = types.supertype(c.type);
1692 if (st.tag == CLASS)
1693 ((ClassType)c.type).supertype_field = types.createErrorType((ClassSymbol)st.tsym, Type.noType);
1694 c.type = types.createErrorType(c, c.type);
1695 c.flags_field |= ACYCLIC;
1696 }
1698 /** Check that all methods which implement some
1699 * method conform to the method they implement.
1700 * @param tree The class definition whose members are checked.
1701 */
1702 void checkImplementations(JCClassDecl tree) {
1703 checkImplementations(tree, tree.sym);
1704 }
1705 //where
1706 /** Check that all methods which implement some
1707 * method in `ic' conform to the method they implement.
1708 */
1709 void checkImplementations(JCClassDecl tree, ClassSymbol ic) {
1710 ClassSymbol origin = tree.sym;
1711 for (List<Type> l = types.closure(ic.type); l.nonEmpty(); l = l.tail) {
1712 ClassSymbol lc = (ClassSymbol)l.head.tsym;
1713 if ((allowGenerics || origin != lc) && (lc.flags() & ABSTRACT) != 0) {
1714 for (Scope.Entry e=lc.members().elems; e != null; e=e.sibling) {
1715 if (e.sym.kind == MTH &&
1716 (e.sym.flags() & (STATIC|ABSTRACT)) == ABSTRACT) {
1717 MethodSymbol absmeth = (MethodSymbol)e.sym;
1718 MethodSymbol implmeth = absmeth.implementation(origin, types, false);
1719 if (implmeth != null && implmeth != absmeth &&
1720 (implmeth.owner.flags() & INTERFACE) ==
1721 (origin.flags() & INTERFACE)) {
1722 // don't check if implmeth is in a class, yet
1723 // origin is an interface. This case arises only
1724 // if implmeth is declared in Object. The reason is
1725 // that interfaces really don't inherit from
1726 // Object it's just that the compiler represents
1727 // things that way.
1728 checkOverride(tree, implmeth, absmeth, origin);
1729 }
1730 }
1731 }
1732 }
1733 }
1734 }
1736 /** Check that all abstract methods implemented by a class are
1737 * mutually compatible.
1738 * @param pos Position to be used for error reporting.
1739 * @param c The class whose interfaces are checked.
1740 */
1741 void checkCompatibleSupertypes(DiagnosticPosition pos, Type c) {
1742 List<Type> supertypes = types.interfaces(c);
1743 Type supertype = types.supertype(c);
1744 if (supertype.tag == CLASS &&
1745 (supertype.tsym.flags() & ABSTRACT) != 0)
1746 supertypes = supertypes.prepend(supertype);
1747 for (List<Type> l = supertypes; l.nonEmpty(); l = l.tail) {
1748 if (allowGenerics && !l.head.getTypeArguments().isEmpty() &&
1749 !checkCompatibleAbstracts(pos, l.head, l.head, c))
1750 return;
1751 for (List<Type> m = supertypes; m != l; m = m.tail)
1752 if (!checkCompatibleAbstracts(pos, l.head, m.head, c))
1753 return;
1754 }
1755 checkCompatibleConcretes(pos, c);
1756 }
1758 void checkConflicts(DiagnosticPosition pos, Symbol sym, TypeSymbol c) {
1759 for (Type ct = c.type; ct != Type.noType ; ct = types.supertype(ct)) {
1760 for (Scope.Entry e = ct.tsym.members().lookup(sym.name); e.scope == ct.tsym.members(); e = e.next()) {
1761 // VM allows methods and variables with differing types
1762 if (sym.kind == e.sym.kind &&
1763 types.isSameType(types.erasure(sym.type), types.erasure(e.sym.type)) &&
1764 sym != e.sym &&
1765 (sym.flags() & Flags.SYNTHETIC) != (e.sym.flags() & Flags.SYNTHETIC) &&
1766 (sym.flags() & BRIDGE) == 0 && (e.sym.flags() & BRIDGE) == 0) {
1767 syntheticError(pos, (e.sym.flags() & SYNTHETIC) == 0 ? e.sym : sym);
1768 return;
1769 }
1770 }
1771 }
1772 }
1774 /** Report a conflict between a user symbol and a synthetic symbol.
1775 */
1776 private void syntheticError(DiagnosticPosition pos, Symbol sym) {
1777 if (!sym.type.isErroneous()) {
1778 if (warnOnSyntheticConflicts) {
1779 log.warning(pos, "synthetic.name.conflict", sym, sym.location());
1780 }
1781 else {
1782 log.error(pos, "synthetic.name.conflict", sym, sym.location());
1783 }
1784 }
1785 }
1787 /** Check that class c does not implement directly or indirectly
1788 * the same parameterized interface with two different argument lists.
1789 * @param pos Position to be used for error reporting.
1790 * @param type The type whose interfaces are checked.
1791 */
1792 void checkClassBounds(DiagnosticPosition pos, Type type) {
1793 checkClassBounds(pos, new HashMap<TypeSymbol,Type>(), type);
1794 }
1795 //where
1796 /** Enter all interfaces of type `type' into the hash table `seensofar'
1797 * with their class symbol as key and their type as value. Make
1798 * sure no class is entered with two different types.
1799 */
1800 void checkClassBounds(DiagnosticPosition pos,
1801 Map<TypeSymbol,Type> seensofar,
1802 Type type) {
1803 if (type.isErroneous()) return;
1804 for (List<Type> l = types.interfaces(type); l.nonEmpty(); l = l.tail) {
1805 Type it = l.head;
1806 Type oldit = seensofar.put(it.tsym, it);
1807 if (oldit != null) {
1808 List<Type> oldparams = oldit.allparams();
1809 List<Type> newparams = it.allparams();
1810 if (!types.containsTypeEquivalent(oldparams, newparams))
1811 log.error(pos, "cant.inherit.diff.arg",
1812 it.tsym, Type.toString(oldparams),
1813 Type.toString(newparams));
1814 }
1815 checkClassBounds(pos, seensofar, it);
1816 }
1817 Type st = types.supertype(type);
1818 if (st != null) checkClassBounds(pos, seensofar, st);
1819 }
1821 /** Enter interface into into set.
1822 * If it existed already, issue a "repeated interface" error.
1823 */
1824 void checkNotRepeated(DiagnosticPosition pos, Type it, Set<Type> its) {
1825 if (its.contains(it))
1826 log.error(pos, "repeated.interface");
1827 else {
1828 its.add(it);
1829 }
1830 }
1832 /* *************************************************************************
1833 * Check annotations
1834 **************************************************************************/
1836 /** Annotation types are restricted to primitives, String, an
1837 * enum, an annotation, Class, Class<?>, Class<? extends
1838 * Anything>, arrays of the preceding.
1839 */
1840 void validateAnnotationType(JCTree restype) {
1841 // restype may be null if an error occurred, so don't bother validating it
1842 if (restype != null) {
1843 validateAnnotationType(restype.pos(), restype.type);
1844 }
1845 }
1847 void validateAnnotationType(DiagnosticPosition pos, Type type) {
1848 if (type.isPrimitive()) return;
1849 if (types.isSameType(type, syms.stringType)) return;
1850 if ((type.tsym.flags() & Flags.ENUM) != 0) return;
1851 if ((type.tsym.flags() & Flags.ANNOTATION) != 0) return;
1852 if (types.lowerBound(type).tsym == syms.classType.tsym) return;
1853 if (types.isArray(type) && !types.isArray(types.elemtype(type))) {
1854 validateAnnotationType(pos, types.elemtype(type));
1855 return;
1856 }
1857 log.error(pos, "invalid.annotation.member.type");
1858 }
1860 /**
1861 * "It is also a compile-time error if any method declared in an
1862 * annotation type has a signature that is override-equivalent to
1863 * that of any public or protected method declared in class Object
1864 * or in the interface annotation.Annotation."
1865 *
1866 * @jls3 9.6 Annotation Types
1867 */
1868 void validateAnnotationMethod(DiagnosticPosition pos, MethodSymbol m) {
1869 for (Type sup = syms.annotationType; sup.tag == CLASS; sup = types.supertype(sup)) {
1870 Scope s = sup.tsym.members();
1871 for (Scope.Entry e = s.lookup(m.name); e.scope != null; e = e.next()) {
1872 if (e.sym.kind == MTH &&
1873 (e.sym.flags() & (PUBLIC | PROTECTED)) != 0 &&
1874 types.overrideEquivalent(m.type, e.sym.type))
1875 log.error(pos, "intf.annotation.member.clash", e.sym, sup);
1876 }
1877 }
1878 }
1880 /** Check the annotations of a symbol.
1881 */
1882 public void validateAnnotations(List<JCAnnotation> annotations, Symbol s) {
1883 if (skipAnnotations) return;
1884 for (JCAnnotation a : annotations)
1885 validateAnnotation(a, s);
1886 }
1888 /** Check the type annotations
1889 */
1890 public void validateTypeAnnotations(List<JCTypeAnnotation> annotations, boolean isTypeParameter) {
1891 if (skipAnnotations) return;
1892 for (JCTypeAnnotation a : annotations)
1893 validateTypeAnnotation(a, isTypeParameter);
1894 }
1896 /** Check an annotation of a symbol.
1897 */
1898 public void validateAnnotation(JCAnnotation a, Symbol s) {
1899 validateAnnotation(a);
1901 if (!annotationApplicable(a, s))
1902 log.error(a.pos(), "annotation.type.not.applicable");
1904 if (a.annotationType.type.tsym == syms.overrideType.tsym) {
1905 if (!isOverrider(s))
1906 log.error(a.pos(), "method.does.not.override.superclass");
1907 }
1908 }
1910 public void validateTypeAnnotation(JCTypeAnnotation a, boolean isTypeParameter) {
1911 if (a.type == null)
1912 throw new AssertionError("annotation tree hasn't been attributed yet: " + a);
1913 validateAnnotation(a);
1915 if (!isTypeAnnotation(a, isTypeParameter))
1916 log.error(a.pos(), "annotation.type.not.applicable");
1917 }
1919 /** Is s a method symbol that overrides a method in a superclass? */
1920 boolean isOverrider(Symbol s) {
1921 if (s.kind != MTH || s.isStatic())
1922 return false;
1923 MethodSymbol m = (MethodSymbol)s;
1924 TypeSymbol owner = (TypeSymbol)m.owner;
1925 for (Type sup : types.closure(owner.type)) {
1926 if (sup == owner.type)
1927 continue; // skip "this"
1928 Scope scope = sup.tsym.members();
1929 for (Scope.Entry e = scope.lookup(m.name); e.scope != null; e = e.next()) {
1930 if (!e.sym.isStatic() && m.overrides(e.sym, owner, types, true))
1931 return true;
1932 }
1933 }
1934 return false;
1935 }
1937 /** Is the annotation applicable to type annotations */
1938 boolean isTypeAnnotation(JCTypeAnnotation a, boolean isTypeParameter) {
1939 Attribute.Compound atTarget =
1940 a.annotationType.type.tsym.attribute(syms.annotationTargetType.tsym);
1941 if (atTarget == null) return true;
1942 Attribute atValue = atTarget.member(names.value);
1943 if (!(atValue instanceof Attribute.Array)) return true; // error recovery
1944 Attribute.Array arr = (Attribute.Array) atValue;
1945 for (Attribute app : arr.values) {
1946 if (!(app instanceof Attribute.Enum)) return true; // recovery
1947 Attribute.Enum e = (Attribute.Enum) app;
1948 if (!isTypeParameter && e.value.name == names.TYPE_USE)
1949 return true;
1950 else if (isTypeParameter && e.value.name == names.TYPE_PARAMETER)
1951 return true;
1952 }
1953 return false;
1954 }
1956 /** Is the annotation applicable to the symbol? */
1957 boolean annotationApplicable(JCAnnotation a, Symbol s) {
1958 Attribute.Compound atTarget =
1959 a.annotationType.type.tsym.attribute(syms.annotationTargetType.tsym);
1960 if (atTarget == null) return true;
1961 Attribute atValue = atTarget.member(names.value);
1962 if (!(atValue instanceof Attribute.Array)) return true; // error recovery
1963 Attribute.Array arr = (Attribute.Array) atValue;
1964 for (Attribute app : arr.values) {
1965 if (!(app instanceof Attribute.Enum)) return true; // recovery
1966 Attribute.Enum e = (Attribute.Enum) app;
1967 if (e.value.name == names.TYPE)
1968 { if (s.kind == TYP) return true; }
1969 else if (e.value.name == names.FIELD)
1970 { if (s.kind == VAR && s.owner.kind != MTH) return true; }
1971 else if (e.value.name == names.METHOD)
1972 { if (s.kind == MTH && !s.isConstructor()) return true; }
1973 else if (e.value.name == names.PARAMETER)
1974 { if (s.kind == VAR &&
1975 s.owner.kind == MTH &&
1976 (s.flags() & PARAMETER) != 0)
1977 return true;
1978 }
1979 else if (e.value.name == names.CONSTRUCTOR)
1980 { if (s.kind == MTH && s.isConstructor()) return true; }
1981 else if (e.value.name == names.LOCAL_VARIABLE)
1982 { if (s.kind == VAR && s.owner.kind == MTH &&
1983 (s.flags() & PARAMETER) == 0)
1984 return true;
1985 }
1986 else if (e.value.name == names.ANNOTATION_TYPE)
1987 { if (s.kind == TYP && (s.flags() & ANNOTATION) != 0)
1988 return true;
1989 }
1990 else if (e.value.name == names.PACKAGE)
1991 { if (s.kind == PCK) return true; }
1992 else if (e.value.name == names.TYPE_USE)
1993 { if (s.kind == TYP ||
1994 s.kind == VAR ||
1995 (s.kind == MTH && !s.isConstructor() &&
1996 s.type.getReturnType().tag != VOID))
1997 return true;
1998 }
1999 else
2000 return true; // recovery
2001 }
2002 return false;
2003 }
2005 /** Check an annotation value.
2006 */
2007 public void validateAnnotation(JCAnnotation a) {
2008 if (a.type.isErroneous()) return;
2010 // collect an inventory of the members
2011 Set<MethodSymbol> members = new HashSet<MethodSymbol>();
2012 for (Scope.Entry e = a.annotationType.type.tsym.members().elems;
2013 e != null;
2014 e = e.sibling)
2015 if (e.sym.kind == MTH)
2016 members.add((MethodSymbol) e.sym);
2018 // count them off as they're annotated
2019 for (JCTree arg : a.args) {
2020 if (arg.getTag() != JCTree.ASSIGN) continue; // recovery
2021 JCAssign assign = (JCAssign) arg;
2022 Symbol m = TreeInfo.symbol(assign.lhs);
2023 if (m == null || m.type.isErroneous()) continue;
2024 if (!members.remove(m))
2025 log.error(assign.lhs.pos(), "duplicate.annotation.member.value",
2026 m.name, a.type);
2027 if (assign.rhs.getTag() == ANNOTATION)
2028 validateAnnotation((JCAnnotation)assign.rhs);
2029 }
2031 // all the remaining ones better have default values
2032 for (MethodSymbol m : members)
2033 if (m.defaultValue == null && !m.type.isErroneous())
2034 log.error(a.pos(), "annotation.missing.default.value",
2035 a.type, m.name);
2037 // special case: java.lang.annotation.Target must not have
2038 // repeated values in its value member
2039 if (a.annotationType.type.tsym != syms.annotationTargetType.tsym ||
2040 a.args.tail == null)
2041 return;
2043 if (a.args.head.getTag() != JCTree.ASSIGN) return; // error recovery
2044 JCAssign assign = (JCAssign) a.args.head;
2045 Symbol m = TreeInfo.symbol(assign.lhs);
2046 if (m.name != names.value) return;
2047 JCTree rhs = assign.rhs;
2048 if (rhs.getTag() != JCTree.NEWARRAY) return;
2049 JCNewArray na = (JCNewArray) rhs;
2050 Set<Symbol> targets = new HashSet<Symbol>();
2051 for (JCTree elem : na.elems) {
2052 if (!targets.add(TreeInfo.symbol(elem))) {
2053 log.error(elem.pos(), "repeated.annotation.target");
2054 }
2055 }
2056 }
2058 void checkDeprecatedAnnotation(DiagnosticPosition pos, Symbol s) {
2059 if (allowAnnotations &&
2060 lint.isEnabled(Lint.LintCategory.DEP_ANN) &&
2061 (s.flags() & DEPRECATED) != 0 &&
2062 !syms.deprecatedType.isErroneous() &&
2063 s.attribute(syms.deprecatedType.tsym) == null) {
2064 log.warning(pos, "missing.deprecated.annotation");
2065 }
2066 }
2068 /* *************************************************************************
2069 * Check for recursive annotation elements.
2070 **************************************************************************/
2072 /** Check for cycles in the graph of annotation elements.
2073 */
2074 void checkNonCyclicElements(JCClassDecl tree) {
2075 if ((tree.sym.flags_field & ANNOTATION) == 0) return;
2076 assert (tree.sym.flags_field & LOCKED) == 0;
2077 try {
2078 tree.sym.flags_field |= LOCKED;
2079 for (JCTree def : tree.defs) {
2080 if (def.getTag() != JCTree.METHODDEF) continue;
2081 JCMethodDecl meth = (JCMethodDecl)def;
2082 checkAnnotationResType(meth.pos(), meth.restype.type);
2083 }
2084 } finally {
2085 tree.sym.flags_field &= ~LOCKED;
2086 tree.sym.flags_field |= ACYCLIC_ANN;
2087 }
2088 }
2090 void checkNonCyclicElementsInternal(DiagnosticPosition pos, TypeSymbol tsym) {
2091 if ((tsym.flags_field & ACYCLIC_ANN) != 0)
2092 return;
2093 if ((tsym.flags_field & LOCKED) != 0) {
2094 log.error(pos, "cyclic.annotation.element");
2095 return;
2096 }
2097 try {
2098 tsym.flags_field |= LOCKED;
2099 for (Scope.Entry e = tsym.members().elems; e != null; e = e.sibling) {
2100 Symbol s = e.sym;
2101 if (s.kind != Kinds.MTH)
2102 continue;
2103 checkAnnotationResType(pos, ((MethodSymbol)s).type.getReturnType());
2104 }
2105 } finally {
2106 tsym.flags_field &= ~LOCKED;
2107 tsym.flags_field |= ACYCLIC_ANN;
2108 }
2109 }
2111 void checkAnnotationResType(DiagnosticPosition pos, Type type) {
2112 switch (type.tag) {
2113 case TypeTags.CLASS:
2114 if ((type.tsym.flags() & ANNOTATION) != 0)
2115 checkNonCyclicElementsInternal(pos, type.tsym);
2116 break;
2117 case TypeTags.ARRAY:
2118 checkAnnotationResType(pos, types.elemtype(type));
2119 break;
2120 default:
2121 break; // int etc
2122 }
2123 }
2125 /* *************************************************************************
2126 * Check for cycles in the constructor call graph.
2127 **************************************************************************/
2129 /** Check for cycles in the graph of constructors calling other
2130 * constructors.
2131 */
2132 void checkCyclicConstructors(JCClassDecl tree) {
2133 Map<Symbol,Symbol> callMap = new HashMap<Symbol, Symbol>();
2135 // enter each constructor this-call into the map
2136 for (List<JCTree> l = tree.defs; l.nonEmpty(); l = l.tail) {
2137 JCMethodInvocation app = TreeInfo.firstConstructorCall(l.head);
2138 if (app == null) continue;
2139 JCMethodDecl meth = (JCMethodDecl) l.head;
2140 if (TreeInfo.name(app.meth) == names._this) {
2141 callMap.put(meth.sym, TreeInfo.symbol(app.meth));
2142 } else {
2143 meth.sym.flags_field |= ACYCLIC;
2144 }
2145 }
2147 // Check for cycles in the map
2148 Symbol[] ctors = new Symbol[0];
2149 ctors = callMap.keySet().toArray(ctors);
2150 for (Symbol caller : ctors) {
2151 checkCyclicConstructor(tree, caller, callMap);
2152 }
2153 }
2155 /** Look in the map to see if the given constructor is part of a
2156 * call cycle.
2157 */
2158 private void checkCyclicConstructor(JCClassDecl tree, Symbol ctor,
2159 Map<Symbol,Symbol> callMap) {
2160 if (ctor != null && (ctor.flags_field & ACYCLIC) == 0) {
2161 if ((ctor.flags_field & LOCKED) != 0) {
2162 log.error(TreeInfo.diagnosticPositionFor(ctor, tree),
2163 "recursive.ctor.invocation");
2164 } else {
2165 ctor.flags_field |= LOCKED;
2166 checkCyclicConstructor(tree, callMap.remove(ctor), callMap);
2167 ctor.flags_field &= ~LOCKED;
2168 }
2169 ctor.flags_field |= ACYCLIC;
2170 }
2171 }
2173 /* *************************************************************************
2174 * Miscellaneous
2175 **************************************************************************/
2177 /**
2178 * Return the opcode of the operator but emit an error if it is an
2179 * error.
2180 * @param pos position for error reporting.
2181 * @param operator an operator
2182 * @param tag a tree tag
2183 * @param left type of left hand side
2184 * @param right type of right hand side
2185 */
2186 int checkOperator(DiagnosticPosition pos,
2187 OperatorSymbol operator,
2188 int tag,
2189 Type left,
2190 Type right) {
2191 if (operator.opcode == ByteCodes.error) {
2192 log.error(pos,
2193 "operator.cant.be.applied",
2194 treeinfo.operatorName(tag),
2195 List.of(left, right));
2196 }
2197 return operator.opcode;
2198 }
2201 /**
2202 * Check for division by integer constant zero
2203 * @param pos Position for error reporting.
2204 * @param operator The operator for the expression
2205 * @param operand The right hand operand for the expression
2206 */
2207 void checkDivZero(DiagnosticPosition pos, Symbol operator, Type operand) {
2208 if (operand.constValue() != null
2209 && lint.isEnabled(Lint.LintCategory.DIVZERO)
2210 && operand.tag <= LONG
2211 && ((Number) (operand.constValue())).longValue() == 0) {
2212 int opc = ((OperatorSymbol)operator).opcode;
2213 if (opc == ByteCodes.idiv || opc == ByteCodes.imod
2214 || opc == ByteCodes.ldiv || opc == ByteCodes.lmod) {
2215 log.warning(pos, "div.zero");
2216 }
2217 }
2218 }
2220 /**
2221 * Check for empty statements after if
2222 */
2223 void checkEmptyIf(JCIf tree) {
2224 if (tree.thenpart.getTag() == JCTree.SKIP && tree.elsepart == null && lint.isEnabled(Lint.LintCategory.EMPTY))
2225 log.warning(tree.thenpart.pos(), "empty.if");
2226 }
2228 /** Check that symbol is unique in given scope.
2229 * @param pos Position for error reporting.
2230 * @param sym The symbol.
2231 * @param s The scope.
2232 */
2233 boolean checkUnique(DiagnosticPosition pos, Symbol sym, Scope s) {
2234 if (sym.type.isErroneous())
2235 return true;
2236 if (sym.owner.name == names.any) return false;
2237 for (Scope.Entry e = s.lookup(sym.name); e.scope == s; e = e.next()) {
2238 if (sym != e.sym &&
2239 sym.kind == e.sym.kind &&
2240 sym.name != names.error &&
2241 (sym.kind != MTH || types.hasSameArgs(types.erasure(sym.type), types.erasure(e.sym.type)))) {
2242 if ((sym.flags() & VARARGS) != (e.sym.flags() & VARARGS))
2243 varargsDuplicateError(pos, sym, e.sym);
2244 else if (sym.kind == MTH && !types.overrideEquivalent(sym.type, e.sym.type))
2245 duplicateErasureError(pos, sym, e.sym);
2246 else
2247 duplicateError(pos, e.sym);
2248 return false;
2249 }
2250 }
2251 return true;
2252 }
2253 //where
2254 /** Report duplicate declaration error.
2255 */
2256 void duplicateErasureError(DiagnosticPosition pos, Symbol sym1, Symbol sym2) {
2257 if (!sym1.type.isErroneous() && !sym2.type.isErroneous()) {
2258 log.error(pos, "name.clash.same.erasure", sym1, sym2);
2259 }
2260 }
2262 /** Check that single-type import is not already imported or top-level defined,
2263 * but make an exception for two single-type imports which denote the same type.
2264 * @param pos Position for error reporting.
2265 * @param sym The symbol.
2266 * @param s The scope
2267 */
2268 boolean checkUniqueImport(DiagnosticPosition pos, Symbol sym, Scope s) {
2269 return checkUniqueImport(pos, sym, s, false);
2270 }
2272 /** Check that static single-type import is not already imported or top-level defined,
2273 * but make an exception for two single-type imports which denote the same type.
2274 * @param pos Position for error reporting.
2275 * @param sym The symbol.
2276 * @param s The scope
2277 * @param staticImport Whether or not this was a static import
2278 */
2279 boolean checkUniqueStaticImport(DiagnosticPosition pos, Symbol sym, Scope s) {
2280 return checkUniqueImport(pos, sym, s, true);
2281 }
2283 /** Check that single-type import is not already imported or top-level defined,
2284 * but make an exception for two single-type imports which denote the same type.
2285 * @param pos Position for error reporting.
2286 * @param sym The symbol.
2287 * @param s The scope.
2288 * @param staticImport Whether or not this was a static import
2289 */
2290 private boolean checkUniqueImport(DiagnosticPosition pos, Symbol sym, Scope s, boolean staticImport) {
2291 for (Scope.Entry e = s.lookup(sym.name); e.scope != null; e = e.next()) {
2292 // is encountered class entered via a class declaration?
2293 boolean isClassDecl = e.scope == s;
2294 if ((isClassDecl || sym != e.sym) &&
2295 sym.kind == e.sym.kind &&
2296 sym.name != names.error) {
2297 if (!e.sym.type.isErroneous()) {
2298 String what = e.sym.toString();
2299 if (!isClassDecl) {
2300 if (staticImport)
2301 log.error(pos, "already.defined.static.single.import", what);
2302 else
2303 log.error(pos, "already.defined.single.import", what);
2304 }
2305 else if (sym != e.sym)
2306 log.error(pos, "already.defined.this.unit", what);
2307 }
2308 return false;
2309 }
2310 }
2311 return true;
2312 }
2314 /** Check that a qualified name is in canonical form (for import decls).
2315 */
2316 public void checkCanonical(JCTree tree) {
2317 if (!isCanonical(tree))
2318 log.error(tree.pos(), "import.requires.canonical",
2319 TreeInfo.symbol(tree));
2320 }
2321 // where
2322 private boolean isCanonical(JCTree tree) {
2323 while (tree.getTag() == JCTree.SELECT) {
2324 JCFieldAccess s = (JCFieldAccess) tree;
2325 if (s.sym.owner != TreeInfo.symbol(s.selected))
2326 return false;
2327 tree = s.selected;
2328 }
2329 return true;
2330 }
2332 private class ConversionWarner extends Warner {
2333 final String key;
2334 final Type found;
2335 final Type expected;
2336 public ConversionWarner(DiagnosticPosition pos, String key, Type found, Type expected) {
2337 super(pos);
2338 this.key = key;
2339 this.found = found;
2340 this.expected = expected;
2341 }
2343 @Override
2344 public void warnUnchecked() {
2345 boolean warned = this.warned;
2346 super.warnUnchecked();
2347 if (warned) return; // suppress redundant diagnostics
2348 Object problem = diags.fragment(key);
2349 Check.this.warnUnchecked(pos(), "prob.found.req", problem, found, expected);
2350 }
2351 }
2353 public Warner castWarner(DiagnosticPosition pos, Type found, Type expected) {
2354 return new ConversionWarner(pos, "unchecked.cast.to.type", found, expected);
2355 }
2357 public Warner convertWarner(DiagnosticPosition pos, Type found, Type expected) {
2358 return new ConversionWarner(pos, "unchecked.assign", found, expected);
2359 }
2360 }
