Mercurial > jdk8-mips64-public > langtools / file revision
src/share/classes/com/sun/tools/javac/comp/Check.java@eff38cc97183
src/share/classes/com/sun/tools/javac/comp/Check.java
Tue, 16 Sep 2008 18:35:18 -0700
- author
- jjg
- date
- Tue, 16 Sep 2008 18:35:18 -0700
- changeset 113
- eff38cc97183
- parent 110
- 91eea580fbe9
- child 122
- 1a9276e7cb18
- permissions
- -rw-r--r--
6574134: Allow for alternative implementation of Name Table with garbage collection of name bytes
Reviewed-by: darcy, mcimadamore
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 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 Target target;
64 private final Source source;
65 private final Types types;
66 private final JCDiagnostic.Factory diags;
67 private final boolean skipAnnotations;
68 private final TreeInfo treeinfo;
70 // The set of lint options currently in effect. It is initialized
71 // from the context, and then is set/reset as needed by Attr as it
72 // visits all the various parts of the trees during attribution.
73 private Lint lint;
75 public static Check instance(Context context) {
76 Check instance = context.get(checkKey);
77 if (instance == null)
78 instance = new Check(context);
79 return instance;
80 }
82 protected Check(Context context) {
83 context.put(checkKey, this);
85 names = Names.instance(context);
86 log = Log.instance(context);
87 syms = Symtab.instance(context);
88 infer = Infer.instance(context);
89 this.types = Types.instance(context);
90 diags = JCDiagnostic.Factory.instance(context);
91 Options options = Options.instance(context);
92 target = Target.instance(context);
93 source = Source.instance(context);
94 lint = Lint.instance(context);
95 treeinfo = TreeInfo.instance(context);
97 Source source = Source.instance(context);
98 allowGenerics = source.allowGenerics();
99 allowAnnotations = source.allowAnnotations();
100 complexInference = options.get("-complexinference") != null;
101 skipAnnotations = options.get("skipAnnotations") != null;
103 boolean verboseDeprecated = lint.isEnabled(LintCategory.DEPRECATION);
104 boolean verboseUnchecked = lint.isEnabled(LintCategory.UNCHECKED);
105 boolean enforceMandatoryWarnings = source.enforceMandatoryWarnings();
107 deprecationHandler = new MandatoryWarningHandler(log, verboseDeprecated,
108 enforceMandatoryWarnings, "deprecated");
109 uncheckedHandler = new MandatoryWarningHandler(log, verboseUnchecked,
110 enforceMandatoryWarnings, "unchecked");
111 }
113 /** Switch: generics enabled?
114 */
115 boolean allowGenerics;
117 /** Switch: annotations enabled?
118 */
119 boolean allowAnnotations;
121 /** Switch: -complexinference option set?
122 */
123 boolean complexInference;
125 /** A table mapping flat names of all compiled classes in this run to their
126 * symbols; maintained from outside.
127 */
128 public Map<Name,ClassSymbol> compiled = new HashMap<Name, ClassSymbol>();
130 /** A handler for messages about deprecated usage.
131 */
132 private MandatoryWarningHandler deprecationHandler;
134 /** A handler for messages about unchecked or unsafe usage.
135 */
136 private MandatoryWarningHandler uncheckedHandler;
139 /* *************************************************************************
140 * Errors and Warnings
141 **************************************************************************/
143 Lint setLint(Lint newLint) {
144 Lint prev = lint;
145 lint = newLint;
146 return prev;
147 }
149 /** Warn about deprecated symbol.
150 * @param pos Position to be used for error reporting.
151 * @param sym The deprecated symbol.
152 */
153 void warnDeprecated(DiagnosticPosition pos, Symbol sym) {
154 if (!lint.isSuppressed(LintCategory.DEPRECATION))
155 deprecationHandler.report(pos, "has.been.deprecated", sym, sym.location());
156 }
158 /** Warn about unchecked operation.
159 * @param pos Position to be used for error reporting.
160 * @param msg A string describing the problem.
161 */
162 public void warnUnchecked(DiagnosticPosition pos, String msg, Object... args) {
163 if (!lint.isSuppressed(LintCategory.UNCHECKED))
164 uncheckedHandler.report(pos, msg, args);
165 }
167 /**
168 * Report any deferred diagnostics.
169 */
170 public void reportDeferredDiagnostics() {
171 deprecationHandler.reportDeferredDiagnostic();
172 uncheckedHandler.reportDeferredDiagnostic();
173 }
176 /** Report a failure to complete a class.
177 * @param pos Position to be used for error reporting.
178 * @param ex The failure to report.
179 */
180 public Type completionError(DiagnosticPosition pos, CompletionFailure ex) {
181 log.error(pos, "cant.access", ex.sym, ex.getDetailValue());
182 if (ex instanceof ClassReader.BadClassFile) throw new Abort();
183 else return syms.errType;
184 }
186 /** Report a type error.
187 * @param pos Position to be used for error reporting.
188 * @param problem A string describing the error.
189 * @param found The type that was found.
190 * @param req The type that was required.
191 */
192 Type typeError(DiagnosticPosition pos, Object problem, Type found, Type req) {
193 log.error(pos, "prob.found.req",
194 problem, found, req);
195 return types.createErrorType(found);
196 }
198 Type typeError(DiagnosticPosition pos, String problem, Type found, Type req, Object explanation) {
199 log.error(pos, "prob.found.req.1", problem, found, req, explanation);
200 return types.createErrorType(found);
201 }
203 /** Report an error that wrong type tag was found.
204 * @param pos Position to be used for error reporting.
205 * @param required An internationalized string describing the type tag
206 * required.
207 * @param found The type that was found.
208 */
209 Type typeTagError(DiagnosticPosition pos, Object required, Object found) {
210 log.error(pos, "type.found.req", found, required);
211 return types.createErrorType(found instanceof Type ? (Type)found : syms.errType);
212 }
214 /** Report an error that symbol cannot be referenced before super
215 * has been called.
216 * @param pos Position to be used for error reporting.
217 * @param sym The referenced symbol.
218 */
219 void earlyRefError(DiagnosticPosition pos, Symbol sym) {
220 log.error(pos, "cant.ref.before.ctor.called", sym);
221 }
223 /** Report duplicate declaration error.
224 */
225 void duplicateError(DiagnosticPosition pos, Symbol sym) {
226 if (!sym.type.isErroneous()) {
227 log.error(pos, "already.defined", sym, sym.location());
228 }
229 }
231 /** Report array/varargs duplicate declaration
232 */
233 void varargsDuplicateError(DiagnosticPosition pos, Symbol sym1, Symbol sym2) {
234 if (!sym1.type.isErroneous() && !sym2.type.isErroneous()) {
235 log.error(pos, "array.and.varargs", sym1, sym2, sym2.location());
236 }
237 }
239 /* ************************************************************************
240 * duplicate declaration checking
241 *************************************************************************/
243 /** Check that variable does not hide variable with same name in
244 * immediately enclosing local scope.
245 * @param pos Position for error reporting.
246 * @param v The symbol.
247 * @param s The scope.
248 */
249 void checkTransparentVar(DiagnosticPosition pos, VarSymbol v, Scope s) {
250 if (s.next != null) {
251 for (Scope.Entry e = s.next.lookup(v.name);
252 e.scope != null && e.sym.owner == v.owner;
253 e = e.next()) {
254 if (e.sym.kind == VAR &&
255 (e.sym.owner.kind & (VAR | MTH)) != 0 &&
256 v.name != names.error) {
257 duplicateError(pos, e.sym);
258 return;
259 }
260 }
261 }
262 }
264 /** Check that a class or interface does not hide a class or
265 * interface with same name in immediately enclosing local scope.
266 * @param pos Position for error reporting.
267 * @param c The symbol.
268 * @param s The scope.
269 */
270 void checkTransparentClass(DiagnosticPosition pos, ClassSymbol c, Scope s) {
271 if (s.next != null) {
272 for (Scope.Entry e = s.next.lookup(c.name);
273 e.scope != null && e.sym.owner == c.owner;
274 e = e.next()) {
275 if (e.sym.kind == TYP &&
276 (e.sym.owner.kind & (VAR | MTH)) != 0 &&
277 c.name != names.error) {
278 duplicateError(pos, e.sym);
279 return;
280 }
281 }
282 }
283 }
285 /** Check that class does not have the same name as one of
286 * its enclosing classes, or as a class defined in its enclosing scope.
287 * return true if class is unique in its enclosing scope.
288 * @param pos Position for error reporting.
289 * @param name The class name.
290 * @param s The enclosing scope.
291 */
292 boolean checkUniqueClassName(DiagnosticPosition pos, Name name, Scope s) {
293 for (Scope.Entry e = s.lookup(name); e.scope == s; e = e.next()) {
294 if (e.sym.kind == TYP && e.sym.name != names.error) {
295 duplicateError(pos, e.sym);
296 return false;
297 }
298 }
299 for (Symbol sym = s.owner; sym != null; sym = sym.owner) {
300 if (sym.kind == TYP && sym.name == name && sym.name != names.error) {
301 duplicateError(pos, sym);
302 return true;
303 }
304 }
305 return true;
306 }
308 /* *************************************************************************
309 * Class name generation
310 **************************************************************************/
312 /** Return name of local class.
313 * This is of the form <enclClass> $ n <classname>
314 * where
315 * enclClass is the flat name of the enclosing class,
316 * classname is the simple name of the local class
317 */
318 Name localClassName(ClassSymbol c) {
319 for (int i=1; ; i++) {
320 Name flatname = names.
321 fromString("" + c.owner.enclClass().flatname +
322 target.syntheticNameChar() + i +
323 c.name);
324 if (compiled.get(flatname) == null) return flatname;
325 }
326 }
328 /* *************************************************************************
329 * Type Checking
330 **************************************************************************/
332 /** Check that a given type is assignable to a given proto-type.
333 * If it is, return the type, otherwise return errType.
334 * @param pos Position to be used for error reporting.
335 * @param found The type that was found.
336 * @param req The type that was required.
337 */
338 Type checkType(DiagnosticPosition pos, Type found, Type req) {
339 if (req.tag == ERROR)
340 return req;
341 if (found.tag == FORALL)
342 return instantiatePoly(pos, (ForAll)found, req, convertWarner(pos, found, req));
343 if (req.tag == NONE)
344 return found;
345 if (types.isAssignable(found, req, convertWarner(pos, found, req)))
346 return found;
347 if (found.tag <= DOUBLE && req.tag <= DOUBLE)
348 return typeError(pos, diags.fragment("possible.loss.of.precision"), found, req);
349 if (found.isSuperBound()) {
350 log.error(pos, "assignment.from.super-bound", found);
351 return types.createErrorType(found);
352 }
353 if (req.isExtendsBound()) {
354 log.error(pos, "assignment.to.extends-bound", req);
355 return types.createErrorType(found);
356 }
357 return typeError(pos, diags.fragment("incompatible.types"), found, req);
358 }
360 /** Instantiate polymorphic type to some prototype, unless
361 * prototype is `anyPoly' in which case polymorphic type
362 * is returned unchanged.
363 */
364 Type instantiatePoly(DiagnosticPosition pos, ForAll t, Type pt, Warner warn) {
365 if (pt == Infer.anyPoly && complexInference) {
366 return t;
367 } else if (pt == Infer.anyPoly || pt.tag == NONE) {
368 Type newpt = t.qtype.tag <= VOID ? t.qtype : syms.objectType;
369 return instantiatePoly(pos, t, newpt, warn);
370 } else if (pt.tag == ERROR) {
371 return pt;
372 } else {
373 try {
374 return infer.instantiateExpr(t, pt, warn);
375 } catch (Infer.NoInstanceException ex) {
376 if (ex.isAmbiguous) {
377 JCDiagnostic d = ex.getDiagnostic();
378 log.error(pos,
379 "undetermined.type" + (d!=null ? ".1" : ""),
380 t, d);
381 return types.createErrorType(pt);
382 } else {
383 JCDiagnostic d = ex.getDiagnostic();
384 return typeError(pos,
385 diags.fragment("incompatible.types" + (d!=null ? ".1" : ""), d),
386 t, pt);
387 }
388 }
389 }
390 }
392 /** Check that a given type can be cast to a given target type.
393 * Return the result of the cast.
394 * @param pos Position to be used for error reporting.
395 * @param found The type that is being cast.
396 * @param req The target type of the cast.
397 */
398 Type checkCastable(DiagnosticPosition pos, Type found, Type req) {
399 if (found.tag == FORALL) {
400 instantiatePoly(pos, (ForAll) found, req, castWarner(pos, found, req));
401 return req;
402 } else if (types.isCastable(found, req, castWarner(pos, found, req))) {
403 return req;
404 } else {
405 return typeError(pos,
406 diags.fragment("inconvertible.types"),
407 found, req);
408 }
409 }
410 //where
411 /** Is type a type variable, or a (possibly multi-dimensional) array of
412 * type variables?
413 */
414 boolean isTypeVar(Type t) {
415 return t.tag == TYPEVAR || t.tag == ARRAY && isTypeVar(types.elemtype(t));
416 }
418 /** Check that a type is within some bounds.
419 *
420 * Used in TypeApply to verify that, e.g., X in V<X> is a valid
421 * type argument.
422 * @param pos Position to be used for error reporting.
423 * @param a The type that should be bounded by bs.
424 * @param bs The bound.
425 */
426 private void checkExtends(DiagnosticPosition pos, Type a, TypeVar bs) {
427 if (a.tag == TYPEVAR && ((TypeVar)a).isCaptured()) {
428 CapturedType ct = (CapturedType)a;
429 boolean ok;
430 if (ct.bound.isErroneous()) {//capture doesn't exist
431 ok = false;
432 }
433 else {
434 switch (ct.wildcard.kind) {
435 case EXTENDS:
436 ok = types.isCastable(bs.getUpperBound(),
437 types.upperBound(a),
438 Warner.noWarnings);
439 break;
440 case SUPER:
441 ok = !types.notSoftSubtype(types.lowerBound(a),
442 bs.getUpperBound());
443 break;
444 case UNBOUND:
445 ok = true;
446 break;
447 default:
448 throw new AssertionError("Invalid bound kind");
449 }
450 }
451 if (!ok)
452 log.error(pos, "not.within.bounds", a);
453 }
454 else {
455 a = types.upperBound(a);
456 for (List<Type> l = types.getBounds(bs); l.nonEmpty(); l = l.tail) {
457 if (!types.isSubtype(a, l.head)) {
458 log.error(pos, "not.within.bounds", a);
459 return;
460 }
461 }
462 }
463 }
465 /** Check that type is different from 'void'.
466 * @param pos Position to be used for error reporting.
467 * @param t The type to be checked.
468 */
469 Type checkNonVoid(DiagnosticPosition pos, Type t) {
470 if (t.tag == VOID) {
471 log.error(pos, "void.not.allowed.here");
472 return types.createErrorType(t);
473 } else {
474 return t;
475 }
476 }
478 /** Check that type is a class or interface type.
479 * @param pos Position to be used for error reporting.
480 * @param t The type to be checked.
481 */
482 Type checkClassType(DiagnosticPosition pos, Type t) {
483 if (t.tag != CLASS && t.tag != ERROR)
484 return typeTagError(pos,
485 diags.fragment("type.req.class"),
486 (t.tag == TYPEVAR)
487 ? diags.fragment("type.parameter", t)
488 : t);
489 else
490 return t;
491 }
493 /** Check that type is a class or interface type.
494 * @param pos Position to be used for error reporting.
495 * @param t The type to be checked.
496 * @param noBounds True if type bounds are illegal here.
497 */
498 Type checkClassType(DiagnosticPosition pos, Type t, boolean noBounds) {
499 t = checkClassType(pos, t);
500 if (noBounds && t.isParameterized()) {
501 List<Type> args = t.getTypeArguments();
502 while (args.nonEmpty()) {
503 if (args.head.tag == WILDCARD)
504 return typeTagError(pos,
505 log.getLocalizedString("type.req.exact"),
506 args.head);
507 args = args.tail;
508 }
509 }
510 return t;
511 }
513 /** Check that type is a reifiable class, interface or array type.
514 * @param pos Position to be used for error reporting.
515 * @param t The type to be checked.
516 */
517 Type checkReifiableReferenceType(DiagnosticPosition pos, Type t) {
518 if (t.tag != CLASS && t.tag != ARRAY && t.tag != ERROR) {
519 return typeTagError(pos,
520 diags.fragment("type.req.class.array"),
521 t);
522 } else if (!types.isReifiable(t)) {
523 log.error(pos, "illegal.generic.type.for.instof");
524 return types.createErrorType(t);
525 } else {
526 return t;
527 }
528 }
530 /** Check that type is a reference type, i.e. a class, interface or array type
531 * or a type variable.
532 * @param pos Position to be used for error reporting.
533 * @param t The type to be checked.
534 */
535 Type checkRefType(DiagnosticPosition pos, Type t) {
536 switch (t.tag) {
537 case CLASS:
538 case ARRAY:
539 case TYPEVAR:
540 case WILDCARD:
541 case ERROR:
542 return t;
543 default:
544 return typeTagError(pos,
545 diags.fragment("type.req.ref"),
546 t);
547 }
548 }
550 /** Check that type is a null or reference type.
551 * @param pos Position to be used for error reporting.
552 * @param t The type to be checked.
553 */
554 Type checkNullOrRefType(DiagnosticPosition pos, Type t) {
555 switch (t.tag) {
556 case CLASS:
557 case ARRAY:
558 case TYPEVAR:
559 case WILDCARD:
560 case BOT:
561 case ERROR:
562 return t;
563 default:
564 return typeTagError(pos,
565 diags.fragment("type.req.ref"),
566 t);
567 }
568 }
570 /** Check that flag set does not contain elements of two conflicting sets. s
571 * Return true if it doesn't.
572 * @param pos Position to be used for error reporting.
573 * @param flags The set of flags to be checked.
574 * @param set1 Conflicting flags set #1.
575 * @param set2 Conflicting flags set #2.
576 */
577 boolean checkDisjoint(DiagnosticPosition pos, long flags, long set1, long set2) {
578 if ((flags & set1) != 0 && (flags & set2) != 0) {
579 log.error(pos,
580 "illegal.combination.of.modifiers",
581 asFlagSet(TreeInfo.firstFlag(flags & set1)),
582 asFlagSet(TreeInfo.firstFlag(flags & set2)));
583 return false;
584 } else
585 return true;
586 }
588 /** Check that given modifiers are legal for given symbol and
589 * return modifiers together with any implicit modififiers for that symbol.
590 * Warning: we can't use flags() here since this method
591 * is called during class enter, when flags() would cause a premature
592 * completion.
593 * @param pos Position to be used for error reporting.
594 * @param flags The set of modifiers given in a definition.
595 * @param sym The defined symbol.
596 */
597 long checkFlags(DiagnosticPosition pos, long flags, Symbol sym, JCTree tree) {
598 long mask;
599 long implicit = 0;
600 switch (sym.kind) {
601 case VAR:
602 if (sym.owner.kind != TYP)
603 mask = LocalVarFlags;
604 else if ((sym.owner.flags_field & INTERFACE) != 0)
605 mask = implicit = InterfaceVarFlags;
606 else
607 mask = VarFlags;
608 break;
609 case MTH:
610 if (sym.name == names.init) {
611 if ((sym.owner.flags_field & ENUM) != 0) {
612 // enum constructors cannot be declared public or
613 // protected and must be implicitly or explicitly
614 // private
615 implicit = PRIVATE;
616 mask = PRIVATE;
617 } else
618 mask = ConstructorFlags;
619 } else if ((sym.owner.flags_field & INTERFACE) != 0)
620 mask = implicit = InterfaceMethodFlags;
621 else {
622 mask = MethodFlags;
623 }
624 // Imply STRICTFP if owner has STRICTFP set.
625 if (((flags|implicit) & Flags.ABSTRACT) == 0)
626 implicit |= sym.owner.flags_field & STRICTFP;
627 break;
628 case TYP:
629 if (sym.isLocal()) {
630 mask = LocalClassFlags;
631 if (sym.name.isEmpty()) { // Anonymous class
632 // Anonymous classes in static methods are themselves static;
633 // that's why we admit STATIC here.
634 mask |= STATIC;
635 // JLS: Anonymous classes are final.
636 implicit |= FINAL;
637 }
638 if ((sym.owner.flags_field & STATIC) == 0 &&
639 (flags & ENUM) != 0)
640 log.error(pos, "enums.must.be.static");
641 } else if (sym.owner.kind == TYP) {
642 mask = MemberClassFlags;
643 if (sym.owner.owner.kind == PCK ||
644 (sym.owner.flags_field & STATIC) != 0)
645 mask |= STATIC;
646 else if ((flags & ENUM) != 0)
647 log.error(pos, "enums.must.be.static");
648 // Nested interfaces and enums are always STATIC (Spec ???)
649 if ((flags & (INTERFACE | ENUM)) != 0 ) implicit = STATIC;
650 } else {
651 mask = ClassFlags;
652 }
653 // Interfaces are always ABSTRACT
654 if ((flags & INTERFACE) != 0) implicit |= ABSTRACT;
656 if ((flags & ENUM) != 0) {
657 // enums can't be declared abstract or final
658 mask &= ~(ABSTRACT | FINAL);
659 implicit |= implicitEnumFinalFlag(tree);
660 }
661 // Imply STRICTFP if owner has STRICTFP set.
662 implicit |= sym.owner.flags_field & STRICTFP;
663 break;
664 default:
665 throw new AssertionError();
666 }
667 long illegal = flags & StandardFlags & ~mask;
668 if (illegal != 0) {
669 if ((illegal & INTERFACE) != 0) {
670 log.error(pos, "intf.not.allowed.here");
671 mask |= INTERFACE;
672 }
673 else {
674 log.error(pos,
675 "mod.not.allowed.here", asFlagSet(illegal));
676 }
677 }
678 else if ((sym.kind == TYP ||
679 // ISSUE: Disallowing abstract&private is no longer appropriate
680 // in the presence of inner classes. Should it be deleted here?
681 checkDisjoint(pos, flags,
682 ABSTRACT,
683 PRIVATE | STATIC))
684 &&
685 checkDisjoint(pos, flags,
686 ABSTRACT | INTERFACE,
687 FINAL | NATIVE | SYNCHRONIZED)
688 &&
689 checkDisjoint(pos, flags,
690 PUBLIC,
691 PRIVATE | PROTECTED)
692 &&
693 checkDisjoint(pos, flags,
694 PRIVATE,
695 PUBLIC | PROTECTED)
696 &&
697 checkDisjoint(pos, flags,
698 FINAL,
699 VOLATILE)
700 &&
701 (sym.kind == TYP ||
702 checkDisjoint(pos, flags,
703 ABSTRACT | NATIVE,
704 STRICTFP))) {
705 // skip
706 }
707 return flags & (mask | ~StandardFlags) | implicit;
708 }
711 /** Determine if this enum should be implicitly final.
712 *
713 * If the enum has no specialized enum contants, it is final.
714 *
715 * If the enum does have specialized enum contants, it is
716 * <i>not</i> final.
717 */
718 private long implicitEnumFinalFlag(JCTree tree) {
719 if (tree.getTag() != JCTree.CLASSDEF) return 0;
720 class SpecialTreeVisitor extends JCTree.Visitor {
721 boolean specialized;
722 SpecialTreeVisitor() {
723 this.specialized = false;
724 };
726 public void visitTree(JCTree tree) { /* no-op */ }
728 public void visitVarDef(JCVariableDecl tree) {
729 if ((tree.mods.flags & ENUM) != 0) {
730 if (tree.init instanceof JCNewClass &&
731 ((JCNewClass) tree.init).def != null) {
732 specialized = true;
733 }
734 }
735 }
736 }
738 SpecialTreeVisitor sts = new SpecialTreeVisitor();
739 JCClassDecl cdef = (JCClassDecl) tree;
740 for (JCTree defs: cdef.defs) {
741 defs.accept(sts);
742 if (sts.specialized) return 0;
743 }
744 return FINAL;
745 }
747 /* *************************************************************************
748 * Type Validation
749 **************************************************************************/
751 /** Validate a type expression. That is,
752 * check that all type arguments of a parametric type are within
753 * their bounds. This must be done in a second phase after type attributon
754 * since a class might have a subclass as type parameter bound. E.g:
755 *
756 * class B<A extends C> { ... }
757 * class C extends B<C> { ... }
758 *
759 * and we can't make sure that the bound is already attributed because
760 * of possible cycles.
761 */
762 private Validator validator = new Validator();
764 /** Visitor method: Validate a type expression, if it is not null, catching
765 * and reporting any completion failures.
766 */
767 void validate(JCTree tree) {
768 try {
769 if (tree != null) tree.accept(validator);
770 } catch (CompletionFailure ex) {
771 completionError(tree.pos(), ex);
772 }
773 }
775 /** Visitor method: Validate a list of type expressions.
776 */
777 void validate(List<? extends JCTree> trees) {
778 for (List<? extends JCTree> l = trees; l.nonEmpty(); l = l.tail)
779 validate(l.head);
780 }
782 /** Visitor method: Validate a list of type parameters.
783 */
784 void validateTypeParams(List<JCTypeParameter> trees) {
785 for (List<JCTypeParameter> l = trees; l.nonEmpty(); l = l.tail)
786 validate(l.head);
787 }
789 /** A visitor class for type validation.
790 */
791 class Validator extends JCTree.Visitor {
793 public void visitTypeArray(JCArrayTypeTree tree) {
794 validate(tree.elemtype);
795 }
797 public void visitTypeApply(JCTypeApply tree) {
798 if (tree.type.tag == CLASS) {
799 List<Type> formals = tree.type.tsym.type.getTypeArguments();
800 List<Type> actuals = types.capture(tree.type).getTypeArguments();
801 List<JCExpression> args = tree.arguments;
802 List<Type> forms = formals;
803 ListBuffer<TypeVar> tvars_buf = new ListBuffer<TypeVar>();
805 // For matching pairs of actual argument types `a' and
806 // formal type parameters with declared bound `b' ...
807 while (args.nonEmpty() && forms.nonEmpty()) {
808 validate(args.head);
810 // exact type arguments needs to know their
811 // bounds (for upper and lower bound
812 // calculations). So we create new TypeVars with
813 // bounds substed with actuals.
814 tvars_buf.append(types.substBound(((TypeVar)forms.head),
815 formals,
816 actuals));
818 args = args.tail;
819 forms = forms.tail;
820 }
822 args = tree.arguments;
823 List<TypeVar> tvars = tvars_buf.toList();
824 while (args.nonEmpty() && tvars.nonEmpty()) {
825 // Let the actual arguments know their bound
826 args.head.type.withTypeVar(tvars.head);
827 args = args.tail;
828 tvars = tvars.tail;
829 }
831 args = tree.arguments;
832 tvars = tvars_buf.toList();
833 while (args.nonEmpty() && tvars.nonEmpty()) {
834 checkExtends(args.head.pos(),
835 actuals.head,
836 tvars.head);
837 args = args.tail;
838 tvars = tvars.tail;
839 actuals = actuals.tail;
840 }
842 // Check that this type is either fully parameterized, or
843 // not parameterized at all.
844 if (tree.type.getEnclosingType().isRaw())
845 log.error(tree.pos(), "improperly.formed.type.inner.raw.param");
846 if (tree.clazz.getTag() == JCTree.SELECT)
847 visitSelectInternal((JCFieldAccess)tree.clazz);
848 }
849 }
851 public void visitTypeParameter(JCTypeParameter tree) {
852 validate(tree.bounds);
853 checkClassBounds(tree.pos(), tree.type);
854 }
856 @Override
857 public void visitWildcard(JCWildcard tree) {
858 if (tree.inner != null)
859 validate(tree.inner);
860 }
862 public void visitSelect(JCFieldAccess tree) {
863 if (tree.type.tag == CLASS) {
864 visitSelectInternal(tree);
866 // Check that this type is either fully parameterized, or
867 // not parameterized at all.
868 if (tree.selected.type.isParameterized() && tree.type.tsym.type.getTypeArguments().nonEmpty())
869 log.error(tree.pos(), "improperly.formed.type.param.missing");
870 }
871 }
872 public void visitSelectInternal(JCFieldAccess tree) {
873 if (tree.type.getEnclosingType().tag != CLASS &&
874 tree.selected.type.isParameterized()) {
875 // The enclosing type is not a class, so we are
876 // looking at a static member type. However, the
877 // qualifying expression is parameterized.
878 log.error(tree.pos(), "cant.select.static.class.from.param.type");
879 } else {
880 // otherwise validate the rest of the expression
881 validate(tree.selected);
882 }
883 }
885 /** Default visitor method: do nothing.
886 */
887 public void visitTree(JCTree tree) {
888 }
889 }
891 /* *************************************************************************
892 * Exception checking
893 **************************************************************************/
895 /* The following methods treat classes as sets that contain
896 * the class itself and all their subclasses
897 */
899 /** Is given type a subtype of some of the types in given list?
900 */
901 boolean subset(Type t, List<Type> ts) {
902 for (List<Type> l = ts; l.nonEmpty(); l = l.tail)
903 if (types.isSubtype(t, l.head)) return true;
904 return false;
905 }
907 /** Is given type a subtype or supertype of
908 * some of the types in given list?
909 */
910 boolean intersects(Type t, List<Type> ts) {
911 for (List<Type> l = ts; l.nonEmpty(); l = l.tail)
912 if (types.isSubtype(t, l.head) || types.isSubtype(l.head, t)) return true;
913 return false;
914 }
916 /** Add type set to given type list, unless it is a subclass of some class
917 * in the list.
918 */
919 List<Type> incl(Type t, List<Type> ts) {
920 return subset(t, ts) ? ts : excl(t, ts).prepend(t);
921 }
923 /** Remove type set from type set list.
924 */
925 List<Type> excl(Type t, List<Type> ts) {
926 if (ts.isEmpty()) {
927 return ts;
928 } else {
929 List<Type> ts1 = excl(t, ts.tail);
930 if (types.isSubtype(ts.head, t)) return ts1;
931 else if (ts1 == ts.tail) return ts;
932 else return ts1.prepend(ts.head);
933 }
934 }
936 /** Form the union of two type set lists.
937 */
938 List<Type> union(List<Type> ts1, List<Type> ts2) {
939 List<Type> ts = ts1;
940 for (List<Type> l = ts2; l.nonEmpty(); l = l.tail)
941 ts = incl(l.head, ts);
942 return ts;
943 }
945 /** Form the difference of two type lists.
946 */
947 List<Type> diff(List<Type> ts1, List<Type> ts2) {
948 List<Type> ts = ts1;
949 for (List<Type> l = ts2; l.nonEmpty(); l = l.tail)
950 ts = excl(l.head, ts);
951 return ts;
952 }
954 /** Form the intersection of two type lists.
955 */
956 public List<Type> intersect(List<Type> ts1, List<Type> ts2) {
957 List<Type> ts = List.nil();
958 for (List<Type> l = ts1; l.nonEmpty(); l = l.tail)
959 if (subset(l.head, ts2)) ts = incl(l.head, ts);
960 for (List<Type> l = ts2; l.nonEmpty(); l = l.tail)
961 if (subset(l.head, ts1)) ts = incl(l.head, ts);
962 return ts;
963 }
965 /** Is exc an exception symbol that need not be declared?
966 */
967 boolean isUnchecked(ClassSymbol exc) {
968 return
969 exc.kind == ERR ||
970 exc.isSubClass(syms.errorType.tsym, types) ||
971 exc.isSubClass(syms.runtimeExceptionType.tsym, types);
972 }
974 /** Is exc an exception type that need not be declared?
975 */
976 boolean isUnchecked(Type exc) {
977 return
978 (exc.tag == TYPEVAR) ? isUnchecked(types.supertype(exc)) :
979 (exc.tag == CLASS) ? isUnchecked((ClassSymbol)exc.tsym) :
980 exc.tag == BOT;
981 }
983 /** Same, but handling completion failures.
984 */
985 boolean isUnchecked(DiagnosticPosition pos, Type exc) {
986 try {
987 return isUnchecked(exc);
988 } catch (CompletionFailure ex) {
989 completionError(pos, ex);
990 return true;
991 }
992 }
994 /** Is exc handled by given exception list?
995 */
996 boolean isHandled(Type exc, List<Type> handled) {
997 return isUnchecked(exc) || subset(exc, handled);
998 }
1000 /** Return all exceptions in thrown list that are not in handled list.
1001 * @param thrown The list of thrown exceptions.
1002 * @param handled The list of handled exceptions.
1003 */
1004 List<Type> unHandled(List<Type> thrown, List<Type> handled) {
1005 List<Type> unhandled = List.nil();
1006 for (List<Type> l = thrown; l.nonEmpty(); l = l.tail)
1007 if (!isHandled(l.head, handled)) unhandled = unhandled.prepend(l.head);
1008 return unhandled;
1009 }
1011 /* *************************************************************************
1012 * Overriding/Implementation checking
1013 **************************************************************************/
1015 /** The level of access protection given by a flag set,
1016 * where PRIVATE is highest and PUBLIC is lowest.
1017 */
1018 static int protection(long flags) {
1019 switch ((short)(flags & AccessFlags)) {
1020 case PRIVATE: return 3;
1021 case PROTECTED: return 1;
1022 default:
1023 case PUBLIC: return 0;
1024 case 0: return 2;
1025 }
1026 }
1028 /** A customized "cannot override" error message.
1029 * @param m The overriding method.
1030 * @param other The overridden method.
1031 * @return An internationalized string.
1032 */
1033 Object cannotOverride(MethodSymbol m, MethodSymbol other) {
1034 String key;
1035 if ((other.owner.flags() & INTERFACE) == 0)
1036 key = "cant.override";
1037 else if ((m.owner.flags() & INTERFACE) == 0)
1038 key = "cant.implement";
1039 else
1040 key = "clashes.with";
1041 return diags.fragment(key, m, m.location(), other, other.location());
1042 }
1044 /** A customized "override" warning message.
1045 * @param m The overriding method.
1046 * @param other The overridden method.
1047 * @return An internationalized string.
1048 */
1049 Object uncheckedOverrides(MethodSymbol m, MethodSymbol other) {
1050 String key;
1051 if ((other.owner.flags() & INTERFACE) == 0)
1052 key = "unchecked.override";
1053 else if ((m.owner.flags() & INTERFACE) == 0)
1054 key = "unchecked.implement";
1055 else
1056 key = "unchecked.clash.with";
1057 return diags.fragment(key, m, m.location(), other, other.location());
1058 }
1060 /** A customized "override" warning message.
1061 * @param m The overriding method.
1062 * @param other The overridden method.
1063 * @return An internationalized string.
1064 */
1065 Object varargsOverrides(MethodSymbol m, MethodSymbol other) {
1066 String key;
1067 if ((other.owner.flags() & INTERFACE) == 0)
1068 key = "varargs.override";
1069 else if ((m.owner.flags() & INTERFACE) == 0)
1070 key = "varargs.implement";
1071 else
1072 key = "varargs.clash.with";
1073 return diags.fragment(key, m, m.location(), other, other.location());
1074 }
1076 /** Check that this method conforms with overridden method 'other'.
1077 * where `origin' is the class where checking started.
1078 * Complications:
1079 * (1) Do not check overriding of synthetic methods
1080 * (reason: they might be final).
1081 * todo: check whether this is still necessary.
1082 * (2) Admit the case where an interface proxy throws fewer exceptions
1083 * than the method it implements. Augment the proxy methods with the
1084 * undeclared exceptions in this case.
1085 * (3) When generics are enabled, admit the case where an interface proxy
1086 * has a result type
1087 * extended by the result type of the method it implements.
1088 * Change the proxies result type to the smaller type in this case.
1089 *
1090 * @param tree The tree from which positions
1091 * are extracted for errors.
1092 * @param m The overriding method.
1093 * @param other The overridden method.
1094 * @param origin The class of which the overriding method
1095 * is a member.
1096 */
1097 void checkOverride(JCTree tree,
1098 MethodSymbol m,
1099 MethodSymbol other,
1100 ClassSymbol origin) {
1101 // Don't check overriding of synthetic methods or by bridge methods.
1102 if ((m.flags() & (SYNTHETIC|BRIDGE)) != 0 || (other.flags() & SYNTHETIC) != 0) {
1103 return;
1104 }
1106 // Error if static method overrides instance method (JLS 8.4.6.2).
1107 if ((m.flags() & STATIC) != 0 &&
1108 (other.flags() & STATIC) == 0) {
1109 log.error(TreeInfo.diagnosticPositionFor(m, tree), "override.static",
1110 cannotOverride(m, other));
1111 return;
1112 }
1114 // Error if instance method overrides static or final
1115 // method (JLS 8.4.6.1).
1116 if ((other.flags() & FINAL) != 0 ||
1117 (m.flags() & STATIC) == 0 &&
1118 (other.flags() & STATIC) != 0) {
1119 log.error(TreeInfo.diagnosticPositionFor(m, tree), "override.meth",
1120 cannotOverride(m, other),
1121 asFlagSet(other.flags() & (FINAL | STATIC)));
1122 return;
1123 }
1125 if ((m.owner.flags() & ANNOTATION) != 0) {
1126 // handled in validateAnnotationMethod
1127 return;
1128 }
1130 // Error if overriding method has weaker access (JLS 8.4.6.3).
1131 if ((origin.flags() & INTERFACE) == 0 &&
1132 protection(m.flags()) > protection(other.flags())) {
1133 log.error(TreeInfo.diagnosticPositionFor(m, tree), "override.weaker.access",
1134 cannotOverride(m, other),
1135 other.flags() == 0 ?
1136 Flag.PACKAGE :
1137 asFlagSet(other.flags() & AccessFlags));
1138 return;
1139 }
1141 Type mt = types.memberType(origin.type, m);
1142 Type ot = types.memberType(origin.type, other);
1143 // Error if overriding result type is different
1144 // (or, in the case of generics mode, not a subtype) of
1145 // overridden result type. We have to rename any type parameters
1146 // before comparing types.
1147 List<Type> mtvars = mt.getTypeArguments();
1148 List<Type> otvars = ot.getTypeArguments();
1149 Type mtres = mt.getReturnType();
1150 Type otres = types.subst(ot.getReturnType(), otvars, mtvars);
1152 overrideWarner.warned = false;
1153 boolean resultTypesOK =
1154 types.returnTypeSubstitutable(mt, ot, otres, overrideWarner);
1155 if (!resultTypesOK) {
1156 if (!source.allowCovariantReturns() &&
1157 m.owner != origin &&
1158 m.owner.isSubClass(other.owner, types)) {
1159 // allow limited interoperability with covariant returns
1160 } else {
1161 typeError(TreeInfo.diagnosticPositionFor(m, tree),
1162 diags.fragment("override.incompatible.ret",
1163 cannotOverride(m, other)),
1164 mtres, otres);
1165 return;
1166 }
1167 } else if (overrideWarner.warned) {
1168 warnUnchecked(TreeInfo.diagnosticPositionFor(m, tree),
1169 "prob.found.req",
1170 diags.fragment("override.unchecked.ret",
1171 uncheckedOverrides(m, other)),
1172 mtres, otres);
1173 }
1175 // Error if overriding method throws an exception not reported
1176 // by overridden method.
1177 List<Type> otthrown = types.subst(ot.getThrownTypes(), otvars, mtvars);
1178 List<Type> unhandled = unHandled(mt.getThrownTypes(), otthrown);
1179 if (unhandled.nonEmpty()) {
1180 log.error(TreeInfo.diagnosticPositionFor(m, tree),
1181 "override.meth.doesnt.throw",
1182 cannotOverride(m, other),
1183 unhandled.head);
1184 return;
1185 }
1187 // Optional warning if varargs don't agree
1188 if ((((m.flags() ^ other.flags()) & Flags.VARARGS) != 0)
1189 && lint.isEnabled(Lint.LintCategory.OVERRIDES)) {
1190 log.warning(TreeInfo.diagnosticPositionFor(m, tree),
1191 ((m.flags() & Flags.VARARGS) != 0)
1192 ? "override.varargs.missing"
1193 : "override.varargs.extra",
1194 varargsOverrides(m, other));
1195 }
1197 // Warn if instance method overrides bridge method (compiler spec ??)
1198 if ((other.flags() & BRIDGE) != 0) {
1199 log.warning(TreeInfo.diagnosticPositionFor(m, tree), "override.bridge",
1200 uncheckedOverrides(m, other));
1201 }
1203 // Warn if a deprecated method overridden by a non-deprecated one.
1204 if ((other.flags() & DEPRECATED) != 0
1205 && (m.flags() & DEPRECATED) == 0
1206 && m.outermostClass() != other.outermostClass()
1207 && !isDeprecatedOverrideIgnorable(other, origin)) {
1208 warnDeprecated(TreeInfo.diagnosticPositionFor(m, tree), other);
1209 }
1210 }
1211 // where
1212 private boolean isDeprecatedOverrideIgnorable(MethodSymbol m, ClassSymbol origin) {
1213 // If the method, m, is defined in an interface, then ignore the issue if the method
1214 // is only inherited via a supertype and also implemented in the supertype,
1215 // because in that case, we will rediscover the issue when examining the method
1216 // in the supertype.
1217 // If the method, m, is not defined in an interface, then the only time we need to
1218 // address the issue is when the method is the supertype implemementation: any other
1219 // case, we will have dealt with when examining the supertype classes
1220 ClassSymbol mc = m.enclClass();
1221 Type st = types.supertype(origin.type);
1222 if (st.tag != CLASS)
1223 return true;
1224 MethodSymbol stimpl = m.implementation((ClassSymbol)st.tsym, types, false);
1226 if (mc != null && ((mc.flags() & INTERFACE) != 0)) {
1227 List<Type> intfs = types.interfaces(origin.type);
1228 return (intfs.contains(mc.type) ? false : (stimpl != null));
1229 }
1230 else
1231 return (stimpl != m);
1232 }
1235 // used to check if there were any unchecked conversions
1236 Warner overrideWarner = new Warner();
1238 /** Check that a class does not inherit two concrete methods
1239 * with the same signature.
1240 * @param pos Position to be used for error reporting.
1241 * @param site The class type to be checked.
1242 */
1243 public void checkCompatibleConcretes(DiagnosticPosition pos, Type site) {
1244 Type sup = types.supertype(site);
1245 if (sup.tag != CLASS) return;
1247 for (Type t1 = sup;
1248 t1.tsym.type.isParameterized();
1249 t1 = types.supertype(t1)) {
1250 for (Scope.Entry e1 = t1.tsym.members().elems;
1251 e1 != null;
1252 e1 = e1.sibling) {
1253 Symbol s1 = e1.sym;
1254 if (s1.kind != MTH ||
1255 (s1.flags() & (STATIC|SYNTHETIC|BRIDGE)) != 0 ||
1256 !s1.isInheritedIn(site.tsym, types) ||
1257 ((MethodSymbol)s1).implementation(site.tsym,
1258 types,
1259 true) != s1)
1260 continue;
1261 Type st1 = types.memberType(t1, s1);
1262 int s1ArgsLength = st1.getParameterTypes().length();
1263 if (st1 == s1.type) continue;
1265 for (Type t2 = sup;
1266 t2.tag == CLASS;
1267 t2 = types.supertype(t2)) {
1268 for (Scope.Entry e2 = t2.tsym.members().lookup(s1.name);
1269 e2.scope != null;
1270 e2 = e2.next()) {
1271 Symbol s2 = e2.sym;
1272 if (s2 == s1 ||
1273 s2.kind != MTH ||
1274 (s2.flags() & (STATIC|SYNTHETIC|BRIDGE)) != 0 ||
1275 s2.type.getParameterTypes().length() != s1ArgsLength ||
1276 !s2.isInheritedIn(site.tsym, types) ||
1277 ((MethodSymbol)s2).implementation(site.tsym,
1278 types,
1279 true) != s2)
1280 continue;
1281 Type st2 = types.memberType(t2, s2);
1282 if (types.overrideEquivalent(st1, st2))
1283 log.error(pos, "concrete.inheritance.conflict",
1284 s1, t1, s2, t2, sup);
1285 }
1286 }
1287 }
1288 }
1289 }
1291 /** Check that classes (or interfaces) do not each define an abstract
1292 * method with same name and arguments but incompatible return types.
1293 * @param pos Position to be used for error reporting.
1294 * @param t1 The first argument type.
1295 * @param t2 The second argument type.
1296 */
1297 public boolean checkCompatibleAbstracts(DiagnosticPosition pos,
1298 Type t1,
1299 Type t2) {
1300 return checkCompatibleAbstracts(pos, t1, t2,
1301 types.makeCompoundType(t1, t2));
1302 }
1304 public boolean checkCompatibleAbstracts(DiagnosticPosition pos,
1305 Type t1,
1306 Type t2,
1307 Type site) {
1308 Symbol sym = firstIncompatibility(t1, t2, site);
1309 if (sym != null) {
1310 log.error(pos, "types.incompatible.diff.ret",
1311 t1, t2, sym.name +
1312 "(" + types.memberType(t2, sym).getParameterTypes() + ")");
1313 return false;
1314 }
1315 return true;
1316 }
1318 /** Return the first method which is defined with same args
1319 * but different return types in two given interfaces, or null if none
1320 * exists.
1321 * @param t1 The first type.
1322 * @param t2 The second type.
1323 * @param site The most derived type.
1324 * @returns symbol from t2 that conflicts with one in t1.
1325 */
1326 private Symbol firstIncompatibility(Type t1, Type t2, Type site) {
1327 Map<TypeSymbol,Type> interfaces1 = new HashMap<TypeSymbol,Type>();
1328 closure(t1, interfaces1);
1329 Map<TypeSymbol,Type> interfaces2;
1330 if (t1 == t2)
1331 interfaces2 = interfaces1;
1332 else
1333 closure(t2, interfaces1, interfaces2 = new HashMap<TypeSymbol,Type>());
1335 for (Type t3 : interfaces1.values()) {
1336 for (Type t4 : interfaces2.values()) {
1337 Symbol s = firstDirectIncompatibility(t3, t4, site);
1338 if (s != null) return s;
1339 }
1340 }
1341 return null;
1342 }
1344 /** Compute all the supertypes of t, indexed by type symbol. */
1345 private void closure(Type t, Map<TypeSymbol,Type> typeMap) {
1346 if (t.tag != CLASS) return;
1347 if (typeMap.put(t.tsym, t) == null) {
1348 closure(types.supertype(t), typeMap);
1349 for (Type i : types.interfaces(t))
1350 closure(i, typeMap);
1351 }
1352 }
1354 /** Compute all the supertypes of t, indexed by type symbol (except thise in typesSkip). */
1355 private void closure(Type t, Map<TypeSymbol,Type> typesSkip, Map<TypeSymbol,Type> typeMap) {
1356 if (t.tag != CLASS) return;
1357 if (typesSkip.get(t.tsym) != null) return;
1358 if (typeMap.put(t.tsym, t) == null) {
1359 closure(types.supertype(t), typesSkip, typeMap);
1360 for (Type i : types.interfaces(t))
1361 closure(i, typesSkip, typeMap);
1362 }
1363 }
1365 /** Return the first method in t2 that conflicts with a method from t1. */
1366 private Symbol firstDirectIncompatibility(Type t1, Type t2, Type site) {
1367 for (Scope.Entry e1 = t1.tsym.members().elems; e1 != null; e1 = e1.sibling) {
1368 Symbol s1 = e1.sym;
1369 Type st1 = null;
1370 if (s1.kind != MTH || !s1.isInheritedIn(site.tsym, types)) continue;
1371 Symbol impl = ((MethodSymbol)s1).implementation(site.tsym, types, false);
1372 if (impl != null && (impl.flags() & ABSTRACT) == 0) continue;
1373 for (Scope.Entry e2 = t2.tsym.members().lookup(s1.name); e2.scope != null; e2 = e2.next()) {
1374 Symbol s2 = e2.sym;
1375 if (s1 == s2) continue;
1376 if (s2.kind != MTH || !s2.isInheritedIn(site.tsym, types)) continue;
1377 if (st1 == null) st1 = types.memberType(t1, s1);
1378 Type st2 = types.memberType(t2, s2);
1379 if (types.overrideEquivalent(st1, st2)) {
1380 List<Type> tvars1 = st1.getTypeArguments();
1381 List<Type> tvars2 = st2.getTypeArguments();
1382 Type rt1 = st1.getReturnType();
1383 Type rt2 = types.subst(st2.getReturnType(), tvars2, tvars1);
1384 boolean compat =
1385 types.isSameType(rt1, rt2) ||
1386 rt1.tag >= CLASS && rt2.tag >= CLASS &&
1387 (types.covariantReturnType(rt1, rt2, Warner.noWarnings) ||
1388 types.covariantReturnType(rt2, rt1, Warner.noWarnings)) ||
1389 checkCommonOverriderIn(s1,s2,site);
1390 if (!compat) return s2;
1391 }
1392 }
1393 }
1394 return null;
1395 }
1396 //WHERE
1397 boolean checkCommonOverriderIn(Symbol s1, Symbol s2, Type site) {
1398 Map<TypeSymbol,Type> supertypes = new HashMap<TypeSymbol,Type>();
1399 Type st1 = types.memberType(site, s1);
1400 Type st2 = types.memberType(site, s2);
1401 closure(site, supertypes);
1402 for (Type t : supertypes.values()) {
1403 for (Scope.Entry e = t.tsym.members().lookup(s1.name); e.scope != null; e = e.next()) {
1404 Symbol s3 = e.sym;
1405 if (s3 == s1 || s3 == s2 || s3.kind != MTH || (s3.flags() & (BRIDGE|SYNTHETIC)) != 0) continue;
1406 Type st3 = types.memberType(site,s3);
1407 if (types.overrideEquivalent(st3, st1) && types.overrideEquivalent(st3, st2)) {
1408 if (s3.owner == site.tsym) {
1409 return true;
1410 }
1411 List<Type> tvars1 = st1.getTypeArguments();
1412 List<Type> tvars2 = st2.getTypeArguments();
1413 List<Type> tvars3 = st3.getTypeArguments();
1414 Type rt1 = st1.getReturnType();
1415 Type rt2 = st2.getReturnType();
1416 Type rt13 = types.subst(st3.getReturnType(), tvars3, tvars1);
1417 Type rt23 = types.subst(st3.getReturnType(), tvars3, tvars2);
1418 boolean compat =
1419 rt13.tag >= CLASS && rt23.tag >= CLASS &&
1420 (types.covariantReturnType(rt13, rt1, Warner.noWarnings) &&
1421 types.covariantReturnType(rt23, rt2, Warner.noWarnings));
1422 if (compat)
1423 return true;
1424 }
1425 }
1426 }
1427 return false;
1428 }
1430 /** Check that a given method conforms with any method it overrides.
1431 * @param tree The tree from which positions are extracted
1432 * for errors.
1433 * @param m The overriding method.
1434 */
1435 void checkOverride(JCTree tree, MethodSymbol m) {
1436 ClassSymbol origin = (ClassSymbol)m.owner;
1437 if ((origin.flags() & ENUM) != 0 && names.finalize.equals(m.name))
1438 if (m.overrides(syms.enumFinalFinalize, origin, types, false)) {
1439 log.error(tree.pos(), "enum.no.finalize");
1440 return;
1441 }
1442 for (Type t = types.supertype(origin.type); t.tag == CLASS;
1443 t = types.supertype(t)) {
1444 TypeSymbol c = t.tsym;
1445 Scope.Entry e = c.members().lookup(m.name);
1446 while (e.scope != null) {
1447 if (m.overrides(e.sym, origin, types, false))
1448 checkOverride(tree, m, (MethodSymbol)e.sym, origin);
1449 else if (e.sym.isInheritedIn(origin, types) && !m.isConstructor()) {
1450 Type er1 = m.erasure(types);
1451 Type er2 = e.sym.erasure(types);
1452 if (types.isSameType(er1,er2)) {
1453 log.error(TreeInfo.diagnosticPositionFor(m, tree),
1454 "name.clash.same.erasure.no.override",
1455 m, m.location(),
1456 e.sym, e.sym.location());
1457 }
1458 }
1459 e = e.next();
1460 }
1461 }
1462 }
1464 /** Check that all abstract members of given class have definitions.
1465 * @param pos Position to be used for error reporting.
1466 * @param c The class.
1467 */
1468 void checkAllDefined(DiagnosticPosition pos, ClassSymbol c) {
1469 try {
1470 MethodSymbol undef = firstUndef(c, c);
1471 if (undef != null) {
1472 if ((c.flags() & ENUM) != 0 &&
1473 types.supertype(c.type).tsym == syms.enumSym &&
1474 (c.flags() & FINAL) == 0) {
1475 // add the ABSTRACT flag to an enum
1476 c.flags_field |= ABSTRACT;
1477 } else {
1478 MethodSymbol undef1 =
1479 new MethodSymbol(undef.flags(), undef.name,
1480 types.memberType(c.type, undef), undef.owner);
1481 log.error(pos, "does.not.override.abstract",
1482 c, undef1, undef1.location());
1483 }
1484 }
1485 } catch (CompletionFailure ex) {
1486 completionError(pos, ex);
1487 }
1488 }
1489 //where
1490 /** Return first abstract member of class `c' that is not defined
1491 * in `impl', null if there is none.
1492 */
1493 private MethodSymbol firstUndef(ClassSymbol impl, ClassSymbol c) {
1494 MethodSymbol undef = null;
1495 // Do not bother to search in classes that are not abstract,
1496 // since they cannot have abstract members.
1497 if (c == impl || (c.flags() & (ABSTRACT | INTERFACE)) != 0) {
1498 Scope s = c.members();
1499 for (Scope.Entry e = s.elems;
1500 undef == null && e != null;
1501 e = e.sibling) {
1502 if (e.sym.kind == MTH &&
1503 (e.sym.flags() & (ABSTRACT|IPROXY)) == ABSTRACT) {
1504 MethodSymbol absmeth = (MethodSymbol)e.sym;
1505 MethodSymbol implmeth = absmeth.implementation(impl, types, true);
1506 if (implmeth == null || implmeth == absmeth)
1507 undef = absmeth;
1508 }
1509 }
1510 if (undef == null) {
1511 Type st = types.supertype(c.type);
1512 if (st.tag == CLASS)
1513 undef = firstUndef(impl, (ClassSymbol)st.tsym);
1514 }
1515 for (List<Type> l = types.interfaces(c.type);
1516 undef == null && l.nonEmpty();
1517 l = l.tail) {
1518 undef = firstUndef(impl, (ClassSymbol)l.head.tsym);
1519 }
1520 }
1521 return undef;
1522 }
1524 /** Check for cyclic references. Issue an error if the
1525 * symbol of the type referred to has a LOCKED flag set.
1526 *
1527 * @param pos Position to be used for error reporting.
1528 * @param t The type referred to.
1529 */
1530 void checkNonCyclic(DiagnosticPosition pos, Type t) {
1531 checkNonCyclicInternal(pos, t);
1532 }
1535 void checkNonCyclic(DiagnosticPosition pos, TypeVar t) {
1536 checkNonCyclic1(pos, t, new HashSet<TypeVar>());
1537 }
1539 private void checkNonCyclic1(DiagnosticPosition pos, Type t, Set<TypeVar> seen) {
1540 final TypeVar tv;
1541 if (t.tag == TYPEVAR && (t.tsym.flags() & UNATTRIBUTED) != 0)
1542 return;
1543 if (seen.contains(t)) {
1544 tv = (TypeVar)t;
1545 tv.bound = types.createErrorType(t);
1546 log.error(pos, "cyclic.inheritance", t);
1547 } else if (t.tag == TYPEVAR) {
1548 tv = (TypeVar)t;
1549 seen.add(tv);
1550 for (Type b : types.getBounds(tv))
1551 checkNonCyclic1(pos, b, seen);
1552 }
1553 }
1555 /** Check for cyclic references. Issue an error if the
1556 * symbol of the type referred to has a LOCKED flag set.
1557 *
1558 * @param pos Position to be used for error reporting.
1559 * @param t The type referred to.
1560 * @returns True if the check completed on all attributed classes
1561 */
1562 private boolean checkNonCyclicInternal(DiagnosticPosition pos, Type t) {
1563 boolean complete = true; // was the check complete?
1564 //- System.err.println("checkNonCyclicInternal("+t+");");//DEBUG
1565 Symbol c = t.tsym;
1566 if ((c.flags_field & ACYCLIC) != 0) return true;
1568 if ((c.flags_field & LOCKED) != 0) {
1569 noteCyclic(pos, (ClassSymbol)c);
1570 } else if (!c.type.isErroneous()) {
1571 try {
1572 c.flags_field |= LOCKED;
1573 if (c.type.tag == CLASS) {
1574 ClassType clazz = (ClassType)c.type;
1575 if (clazz.interfaces_field != null)
1576 for (List<Type> l=clazz.interfaces_field; l.nonEmpty(); l=l.tail)
1577 complete &= checkNonCyclicInternal(pos, l.head);
1578 if (clazz.supertype_field != null) {
1579 Type st = clazz.supertype_field;
1580 if (st != null && st.tag == CLASS)
1581 complete &= checkNonCyclicInternal(pos, st);
1582 }
1583 if (c.owner.kind == TYP)
1584 complete &= checkNonCyclicInternal(pos, c.owner.type);
1585 }
1586 } finally {
1587 c.flags_field &= ~LOCKED;
1588 }
1589 }
1590 if (complete)
1591 complete = ((c.flags_field & UNATTRIBUTED) == 0) && c.completer == null;
1592 if (complete) c.flags_field |= ACYCLIC;
1593 return complete;
1594 }
1596 /** Note that we found an inheritance cycle. */
1597 private void noteCyclic(DiagnosticPosition pos, ClassSymbol c) {
1598 log.error(pos, "cyclic.inheritance", c);
1599 for (List<Type> l=types.interfaces(c.type); l.nonEmpty(); l=l.tail)
1600 l.head = types.createErrorType((ClassSymbol)l.head.tsym, Type.noType);
1601 Type st = types.supertype(c.type);
1602 if (st.tag == CLASS)
1603 ((ClassType)c.type).supertype_field = types.createErrorType((ClassSymbol)st.tsym, Type.noType);
1604 c.type = types.createErrorType(c, c.type);
1605 c.flags_field |= ACYCLIC;
1606 }
1608 /** Check that all methods which implement some
1609 * method conform to the method they implement.
1610 * @param tree The class definition whose members are checked.
1611 */
1612 void checkImplementations(JCClassDecl tree) {
1613 checkImplementations(tree, tree.sym);
1614 }
1615 //where
1616 /** Check that all methods which implement some
1617 * method in `ic' conform to the method they implement.
1618 */
1619 void checkImplementations(JCClassDecl tree, ClassSymbol ic) {
1620 ClassSymbol origin = tree.sym;
1621 for (List<Type> l = types.closure(ic.type); l.nonEmpty(); l = l.tail) {
1622 ClassSymbol lc = (ClassSymbol)l.head.tsym;
1623 if ((allowGenerics || origin != lc) && (lc.flags() & ABSTRACT) != 0) {
1624 for (Scope.Entry e=lc.members().elems; e != null; e=e.sibling) {
1625 if (e.sym.kind == MTH &&
1626 (e.sym.flags() & (STATIC|ABSTRACT)) == ABSTRACT) {
1627 MethodSymbol absmeth = (MethodSymbol)e.sym;
1628 MethodSymbol implmeth = absmeth.implementation(origin, types, false);
1629 if (implmeth != null && implmeth != absmeth &&
1630 (implmeth.owner.flags() & INTERFACE) ==
1631 (origin.flags() & INTERFACE)) {
1632 // don't check if implmeth is in a class, yet
1633 // origin is an interface. This case arises only
1634 // if implmeth is declared in Object. The reason is
1635 // that interfaces really don't inherit from
1636 // Object it's just that the compiler represents
1637 // things that way.
1638 checkOverride(tree, implmeth, absmeth, origin);
1639 }
1640 }
1641 }
1642 }
1643 }
1644 }
1646 /** Check that all abstract methods implemented by a class are
1647 * mutually compatible.
1648 * @param pos Position to be used for error reporting.
1649 * @param c The class whose interfaces are checked.
1650 */
1651 void checkCompatibleSupertypes(DiagnosticPosition pos, Type c) {
1652 List<Type> supertypes = types.interfaces(c);
1653 Type supertype = types.supertype(c);
1654 if (supertype.tag == CLASS &&
1655 (supertype.tsym.flags() & ABSTRACT) != 0)
1656 supertypes = supertypes.prepend(supertype);
1657 for (List<Type> l = supertypes; l.nonEmpty(); l = l.tail) {
1658 if (allowGenerics && !l.head.getTypeArguments().isEmpty() &&
1659 !checkCompatibleAbstracts(pos, l.head, l.head, c))
1660 return;
1661 for (List<Type> m = supertypes; m != l; m = m.tail)
1662 if (!checkCompatibleAbstracts(pos, l.head, m.head, c))
1663 return;
1664 }
1665 checkCompatibleConcretes(pos, c);
1666 }
1668 /** Check that class c does not implement directly or indirectly
1669 * the same parameterized interface with two different argument lists.
1670 * @param pos Position to be used for error reporting.
1671 * @param type The type whose interfaces are checked.
1672 */
1673 void checkClassBounds(DiagnosticPosition pos, Type type) {
1674 checkClassBounds(pos, new HashMap<TypeSymbol,Type>(), type);
1675 }
1676 //where
1677 /** Enter all interfaces of type `type' into the hash table `seensofar'
1678 * with their class symbol as key and their type as value. Make
1679 * sure no class is entered with two different types.
1680 */
1681 void checkClassBounds(DiagnosticPosition pos,
1682 Map<TypeSymbol,Type> seensofar,
1683 Type type) {
1684 if (type.isErroneous()) return;
1685 for (List<Type> l = types.interfaces(type); l.nonEmpty(); l = l.tail) {
1686 Type it = l.head;
1687 Type oldit = seensofar.put(it.tsym, it);
1688 if (oldit != null) {
1689 List<Type> oldparams = oldit.allparams();
1690 List<Type> newparams = it.allparams();
1691 if (!types.containsTypeEquivalent(oldparams, newparams))
1692 log.error(pos, "cant.inherit.diff.arg",
1693 it.tsym, Type.toString(oldparams),
1694 Type.toString(newparams));
1695 }
1696 checkClassBounds(pos, seensofar, it);
1697 }
1698 Type st = types.supertype(type);
1699 if (st != null) checkClassBounds(pos, seensofar, st);
1700 }
1702 /** Enter interface into into set.
1703 * If it existed already, issue a "repeated interface" error.
1704 */
1705 void checkNotRepeated(DiagnosticPosition pos, Type it, Set<Type> its) {
1706 if (its.contains(it))
1707 log.error(pos, "repeated.interface");
1708 else {
1709 its.add(it);
1710 }
1711 }
1713 /* *************************************************************************
1714 * Check annotations
1715 **************************************************************************/
1717 /** Annotation types are restricted to primitives, String, an
1718 * enum, an annotation, Class, Class<?>, Class<? extends
1719 * Anything>, arrays of the preceding.
1720 */
1721 void validateAnnotationType(JCTree restype) {
1722 // restype may be null if an error occurred, so don't bother validating it
1723 if (restype != null) {
1724 validateAnnotationType(restype.pos(), restype.type);
1725 }
1726 }
1728 void validateAnnotationType(DiagnosticPosition pos, Type type) {
1729 if (type.isPrimitive()) return;
1730 if (types.isSameType(type, syms.stringType)) return;
1731 if ((type.tsym.flags() & Flags.ENUM) != 0) return;
1732 if ((type.tsym.flags() & Flags.ANNOTATION) != 0) return;
1733 if (types.lowerBound(type).tsym == syms.classType.tsym) return;
1734 if (types.isArray(type) && !types.isArray(types.elemtype(type))) {
1735 validateAnnotationType(pos, types.elemtype(type));
1736 return;
1737 }
1738 log.error(pos, "invalid.annotation.member.type");
1739 }
1741 /**
1742 * "It is also a compile-time error if any method declared in an
1743 * annotation type has a signature that is override-equivalent to
1744 * that of any public or protected method declared in class Object
1745 * or in the interface annotation.Annotation."
1746 *
1747 * @jls3 9.6 Annotation Types
1748 */
1749 void validateAnnotationMethod(DiagnosticPosition pos, MethodSymbol m) {
1750 for (Type sup = syms.annotationType; sup.tag == CLASS; sup = types.supertype(sup)) {
1751 Scope s = sup.tsym.members();
1752 for (Scope.Entry e = s.lookup(m.name); e.scope != null; e = e.next()) {
1753 if (e.sym.kind == MTH &&
1754 (e.sym.flags() & (PUBLIC | PROTECTED)) != 0 &&
1755 types.overrideEquivalent(m.type, e.sym.type))
1756 log.error(pos, "intf.annotation.member.clash", e.sym, sup);
1757 }
1758 }
1759 }
1761 /** Check the annotations of a symbol.
1762 */
1763 public void validateAnnotations(List<JCAnnotation> annotations, Symbol s) {
1764 if (skipAnnotations) return;
1765 for (JCAnnotation a : annotations)
1766 validateAnnotation(a, s);
1767 }
1769 /** Check an annotation of a symbol.
1770 */
1771 public void validateAnnotation(JCAnnotation a, Symbol s) {
1772 validateAnnotation(a);
1774 if (!annotationApplicable(a, s))
1775 log.error(a.pos(), "annotation.type.not.applicable");
1777 if (a.annotationType.type.tsym == syms.overrideType.tsym) {
1778 if (!isOverrider(s))
1779 log.error(a.pos(), "method.does.not.override.superclass");
1780 }
1781 }
1783 /** Is s a method symbol that overrides a method in a superclass? */
1784 boolean isOverrider(Symbol s) {
1785 if (s.kind != MTH || s.isStatic())
1786 return false;
1787 MethodSymbol m = (MethodSymbol)s;
1788 TypeSymbol owner = (TypeSymbol)m.owner;
1789 for (Type sup : types.closure(owner.type)) {
1790 if (sup == owner.type)
1791 continue; // skip "this"
1792 Scope scope = sup.tsym.members();
1793 for (Scope.Entry e = scope.lookup(m.name); e.scope != null; e = e.next()) {
1794 if (!e.sym.isStatic() && m.overrides(e.sym, owner, types, true))
1795 return true;
1796 }
1797 }
1798 return false;
1799 }
1801 /** Is the annotation applicable to the symbol? */
1802 boolean annotationApplicable(JCAnnotation a, Symbol s) {
1803 Attribute.Compound atTarget =
1804 a.annotationType.type.tsym.attribute(syms.annotationTargetType.tsym);
1805 if (atTarget == null) return true;
1806 Attribute atValue = atTarget.member(names.value);
1807 if (!(atValue instanceof Attribute.Array)) return true; // error recovery
1808 Attribute.Array arr = (Attribute.Array) atValue;
1809 for (Attribute app : arr.values) {
1810 if (!(app instanceof Attribute.Enum)) return true; // recovery
1811 Attribute.Enum e = (Attribute.Enum) app;
1812 if (e.value.name == names.TYPE)
1813 { if (s.kind == TYP) return true; }
1814 else if (e.value.name == names.FIELD)
1815 { if (s.kind == VAR && s.owner.kind != MTH) return true; }
1816 else if (e.value.name == names.METHOD)
1817 { if (s.kind == MTH && !s.isConstructor()) return true; }
1818 else if (e.value.name == names.PARAMETER)
1819 { if (s.kind == VAR &&
1820 s.owner.kind == MTH &&
1821 (s.flags() & PARAMETER) != 0)
1822 return true;
1823 }
1824 else if (e.value.name == names.CONSTRUCTOR)
1825 { if (s.kind == MTH && s.isConstructor()) return true; }
1826 else if (e.value.name == names.LOCAL_VARIABLE)
1827 { if (s.kind == VAR && s.owner.kind == MTH &&
1828 (s.flags() & PARAMETER) == 0)
1829 return true;
1830 }
1831 else if (e.value.name == names.ANNOTATION_TYPE)
1832 { if (s.kind == TYP && (s.flags() & ANNOTATION) != 0)
1833 return true;
1834 }
1835 else if (e.value.name == names.PACKAGE)
1836 { if (s.kind == PCK) return true; }
1837 else
1838 return true; // recovery
1839 }
1840 return false;
1841 }
1843 /** Check an annotation value.
1844 */
1845 public void validateAnnotation(JCAnnotation a) {
1846 if (a.type.isErroneous()) return;
1848 // collect an inventory of the members
1849 Set<MethodSymbol> members = new HashSet<MethodSymbol>();
1850 for (Scope.Entry e = a.annotationType.type.tsym.members().elems;
1851 e != null;
1852 e = e.sibling)
1853 if (e.sym.kind == MTH)
1854 members.add((MethodSymbol) e.sym);
1856 // count them off as they're annotated
1857 for (JCTree arg : a.args) {
1858 if (arg.getTag() != JCTree.ASSIGN) continue; // recovery
1859 JCAssign assign = (JCAssign) arg;
1860 Symbol m = TreeInfo.symbol(assign.lhs);
1861 if (m == null || m.type.isErroneous()) continue;
1862 if (!members.remove(m))
1863 log.error(arg.pos(), "duplicate.annotation.member.value",
1864 m.name, a.type);
1865 if (assign.rhs.getTag() == ANNOTATION)
1866 validateAnnotation((JCAnnotation)assign.rhs);
1867 }
1869 // all the remaining ones better have default values
1870 for (MethodSymbol m : members)
1871 if (m.defaultValue == null && !m.type.isErroneous())
1872 log.error(a.pos(), "annotation.missing.default.value",
1873 a.type, m.name);
1875 // special case: java.lang.annotation.Target must not have
1876 // repeated values in its value member
1877 if (a.annotationType.type.tsym != syms.annotationTargetType.tsym ||
1878 a.args.tail == null)
1879 return;
1881 if (a.args.head.getTag() != JCTree.ASSIGN) return; // error recovery
1882 JCAssign assign = (JCAssign) a.args.head;
1883 Symbol m = TreeInfo.symbol(assign.lhs);
1884 if (m.name != names.value) return;
1885 JCTree rhs = assign.rhs;
1886 if (rhs.getTag() != JCTree.NEWARRAY) return;
1887 JCNewArray na = (JCNewArray) rhs;
1888 Set<Symbol> targets = new HashSet<Symbol>();
1889 for (JCTree elem : na.elems) {
1890 if (!targets.add(TreeInfo.symbol(elem))) {
1891 log.error(elem.pos(), "repeated.annotation.target");
1892 }
1893 }
1894 }
1896 void checkDeprecatedAnnotation(DiagnosticPosition pos, Symbol s) {
1897 if (allowAnnotations &&
1898 lint.isEnabled(Lint.LintCategory.DEP_ANN) &&
1899 (s.flags() & DEPRECATED) != 0 &&
1900 !syms.deprecatedType.isErroneous() &&
1901 s.attribute(syms.deprecatedType.tsym) == null) {
1902 log.warning(pos, "missing.deprecated.annotation");
1903 }
1904 }
1906 /* *************************************************************************
1907 * Check for recursive annotation elements.
1908 **************************************************************************/
1910 /** Check for cycles in the graph of annotation elements.
1911 */
1912 void checkNonCyclicElements(JCClassDecl tree) {
1913 if ((tree.sym.flags_field & ANNOTATION) == 0) return;
1914 assert (tree.sym.flags_field & LOCKED) == 0;
1915 try {
1916 tree.sym.flags_field |= LOCKED;
1917 for (JCTree def : tree.defs) {
1918 if (def.getTag() != JCTree.METHODDEF) continue;
1919 JCMethodDecl meth = (JCMethodDecl)def;
1920 checkAnnotationResType(meth.pos(), meth.restype.type);
1921 }
1922 } finally {
1923 tree.sym.flags_field &= ~LOCKED;
1924 tree.sym.flags_field |= ACYCLIC_ANN;
1925 }
1926 }
1928 void checkNonCyclicElementsInternal(DiagnosticPosition pos, TypeSymbol tsym) {
1929 if ((tsym.flags_field & ACYCLIC_ANN) != 0)
1930 return;
1931 if ((tsym.flags_field & LOCKED) != 0) {
1932 log.error(pos, "cyclic.annotation.element");
1933 return;
1934 }
1935 try {
1936 tsym.flags_field |= LOCKED;
1937 for (Scope.Entry e = tsym.members().elems; e != null; e = e.sibling) {
1938 Symbol s = e.sym;
1939 if (s.kind != Kinds.MTH)
1940 continue;
1941 checkAnnotationResType(pos, ((MethodSymbol)s).type.getReturnType());
1942 }
1943 } finally {
1944 tsym.flags_field &= ~LOCKED;
1945 tsym.flags_field |= ACYCLIC_ANN;
1946 }
1947 }
1949 void checkAnnotationResType(DiagnosticPosition pos, Type type) {
1950 switch (type.tag) {
1951 case TypeTags.CLASS:
1952 if ((type.tsym.flags() & ANNOTATION) != 0)
1953 checkNonCyclicElementsInternal(pos, type.tsym);
1954 break;
1955 case TypeTags.ARRAY:
1956 checkAnnotationResType(pos, types.elemtype(type));
1957 break;
1958 default:
1959 break; // int etc
1960 }
1961 }
1963 /* *************************************************************************
1964 * Check for cycles in the constructor call graph.
1965 **************************************************************************/
1967 /** Check for cycles in the graph of constructors calling other
1968 * constructors.
1969 */
1970 void checkCyclicConstructors(JCClassDecl tree) {
1971 Map<Symbol,Symbol> callMap = new HashMap<Symbol, Symbol>();
1973 // enter each constructor this-call into the map
1974 for (List<JCTree> l = tree.defs; l.nonEmpty(); l = l.tail) {
1975 JCMethodInvocation app = TreeInfo.firstConstructorCall(l.head);
1976 if (app == null) continue;
1977 JCMethodDecl meth = (JCMethodDecl) l.head;
1978 if (TreeInfo.name(app.meth) == names._this) {
1979 callMap.put(meth.sym, TreeInfo.symbol(app.meth));
1980 } else {
1981 meth.sym.flags_field |= ACYCLIC;
1982 }
1983 }
1985 // Check for cycles in the map
1986 Symbol[] ctors = new Symbol[0];
1987 ctors = callMap.keySet().toArray(ctors);
1988 for (Symbol caller : ctors) {
1989 checkCyclicConstructor(tree, caller, callMap);
1990 }
1991 }
1993 /** Look in the map to see if the given constructor is part of a
1994 * call cycle.
1995 */
1996 private void checkCyclicConstructor(JCClassDecl tree, Symbol ctor,
1997 Map<Symbol,Symbol> callMap) {
1998 if (ctor != null && (ctor.flags_field & ACYCLIC) == 0) {
1999 if ((ctor.flags_field & LOCKED) != 0) {
2000 log.error(TreeInfo.diagnosticPositionFor(ctor, tree),
2001 "recursive.ctor.invocation");
2002 } else {
2003 ctor.flags_field |= LOCKED;
2004 checkCyclicConstructor(tree, callMap.remove(ctor), callMap);
2005 ctor.flags_field &= ~LOCKED;
2006 }
2007 ctor.flags_field |= ACYCLIC;
2008 }
2009 }
2011 /* *************************************************************************
2012 * Miscellaneous
2013 **************************************************************************/
2015 /**
2016 * Return the opcode of the operator but emit an error if it is an
2017 * error.
2018 * @param pos position for error reporting.
2019 * @param operator an operator
2020 * @param tag a tree tag
2021 * @param left type of left hand side
2022 * @param right type of right hand side
2023 */
2024 int checkOperator(DiagnosticPosition pos,
2025 OperatorSymbol operator,
2026 int tag,
2027 Type left,
2028 Type right) {
2029 if (operator.opcode == ByteCodes.error) {
2030 log.error(pos,
2031 "operator.cant.be.applied",
2032 treeinfo.operatorName(tag),
2033 List.of(left, right));
2034 }
2035 return operator.opcode;
2036 }
2039 /**
2040 * Check for division by integer constant zero
2041 * @param pos Position for error reporting.
2042 * @param operator The operator for the expression
2043 * @param operand The right hand operand for the expression
2044 */
2045 void checkDivZero(DiagnosticPosition pos, Symbol operator, Type operand) {
2046 if (operand.constValue() != null
2047 && lint.isEnabled(Lint.LintCategory.DIVZERO)
2048 && operand.tag <= LONG
2049 && ((Number) (operand.constValue())).longValue() == 0) {
2050 int opc = ((OperatorSymbol)operator).opcode;
2051 if (opc == ByteCodes.idiv || opc == ByteCodes.imod
2052 || opc == ByteCodes.ldiv || opc == ByteCodes.lmod) {
2053 log.warning(pos, "div.zero");
2054 }
2055 }
2056 }
2058 /**
2059 * Check for empty statements after if
2060 */
2061 void checkEmptyIf(JCIf tree) {
2062 if (tree.thenpart.getTag() == JCTree.SKIP && tree.elsepart == null && lint.isEnabled(Lint.LintCategory.EMPTY))
2063 log.warning(tree.thenpart.pos(), "empty.if");
2064 }
2066 /** Check that symbol is unique in given scope.
2067 * @param pos Position for error reporting.
2068 * @param sym The symbol.
2069 * @param s The scope.
2070 */
2071 boolean checkUnique(DiagnosticPosition pos, Symbol sym, Scope s) {
2072 if (sym.type.isErroneous())
2073 return true;
2074 if (sym.owner.name == names.any) return false;
2075 for (Scope.Entry e = s.lookup(sym.name); e.scope == s; e = e.next()) {
2076 if (sym != e.sym &&
2077 sym.kind == e.sym.kind &&
2078 sym.name != names.error &&
2079 (sym.kind != MTH || types.overrideEquivalent(sym.type, e.sym.type))) {
2080 if ((sym.flags() & VARARGS) != (e.sym.flags() & VARARGS))
2081 varargsDuplicateError(pos, sym, e.sym);
2082 else
2083 duplicateError(pos, e.sym);
2084 return false;
2085 }
2086 }
2087 return true;
2088 }
2090 /** Check that single-type import is not already imported or top-level defined,
2091 * but make an exception for two single-type imports which denote the same type.
2092 * @param pos Position for error reporting.
2093 * @param sym The symbol.
2094 * @param s The scope
2095 */
2096 boolean checkUniqueImport(DiagnosticPosition pos, Symbol sym, Scope s) {
2097 return checkUniqueImport(pos, sym, s, false);
2098 }
2100 /** Check that static single-type import is not already imported or top-level defined,
2101 * but make an exception for two single-type imports which denote the same type.
2102 * @param pos Position for error reporting.
2103 * @param sym The symbol.
2104 * @param s The scope
2105 * @param staticImport Whether or not this was a static import
2106 */
2107 boolean checkUniqueStaticImport(DiagnosticPosition pos, Symbol sym, Scope s) {
2108 return checkUniqueImport(pos, sym, s, true);
2109 }
2111 /** Check that single-type import is not already imported or top-level defined,
2112 * but make an exception for two single-type imports which denote the same type.
2113 * @param pos Position for error reporting.
2114 * @param sym The symbol.
2115 * @param s The scope.
2116 * @param staticImport Whether or not this was a static import
2117 */
2118 private boolean checkUniqueImport(DiagnosticPosition pos, Symbol sym, Scope s, boolean staticImport) {
2119 for (Scope.Entry e = s.lookup(sym.name); e.scope != null; e = e.next()) {
2120 // is encountered class entered via a class declaration?
2121 boolean isClassDecl = e.scope == s;
2122 if ((isClassDecl || sym != e.sym) &&
2123 sym.kind == e.sym.kind &&
2124 sym.name != names.error) {
2125 if (!e.sym.type.isErroneous()) {
2126 String what = e.sym.toString();
2127 if (!isClassDecl) {
2128 if (staticImport)
2129 log.error(pos, "already.defined.static.single.import", what);
2130 else
2131 log.error(pos, "already.defined.single.import", what);
2132 }
2133 else if (sym != e.sym)
2134 log.error(pos, "already.defined.this.unit", what);
2135 }
2136 return false;
2137 }
2138 }
2139 return true;
2140 }
2142 /** Check that a qualified name is in canonical form (for import decls).
2143 */
2144 public void checkCanonical(JCTree tree) {
2145 if (!isCanonical(tree))
2146 log.error(tree.pos(), "import.requires.canonical",
2147 TreeInfo.symbol(tree));
2148 }
2149 // where
2150 private boolean isCanonical(JCTree tree) {
2151 while (tree.getTag() == JCTree.SELECT) {
2152 JCFieldAccess s = (JCFieldAccess) tree;
2153 if (s.sym.owner != TreeInfo.symbol(s.selected))
2154 return false;
2155 tree = s.selected;
2156 }
2157 return true;
2158 }
2160 private class ConversionWarner extends Warner {
2161 final String key;
2162 final Type found;
2163 final Type expected;
2164 public ConversionWarner(DiagnosticPosition pos, String key, Type found, Type expected) {
2165 super(pos);
2166 this.key = key;
2167 this.found = found;
2168 this.expected = expected;
2169 }
2171 public void warnUnchecked() {
2172 boolean warned = this.warned;
2173 super.warnUnchecked();
2174 if (warned) return; // suppress redundant diagnostics
2175 Object problem = diags.fragment(key);
2176 Check.this.warnUnchecked(pos(), "prob.found.req", problem, found, expected);
2177 }
2178 }
2180 public Warner castWarner(DiagnosticPosition pos, Type found, Type expected) {
2181 return new ConversionWarner(pos, "unchecked.cast.to.type", found, expected);
2182 }
2184 public Warner convertWarner(DiagnosticPosition pos, Type found, Type expected) {
2185 return new ConversionWarner(pos, "unchecked.assign", found, expected);
2186 }
2187 }
