Mon, 04 May 2009 21:04:04 -0700
6829189: Java programming with JSR 292 needs language support
Summary: Language changes documented in http://wikis.sun.com/display/mlvm/ProjectCoinProposal
Reviewed-by: jjg, darcy, mcimadamore
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 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 // this error used to be raised by the parser,
211 // but has been delayed to this point:
212 if (found instanceof Type && ((Type)found).tag == VOID) {
213 log.error(pos, "illegal.start.of.type");
214 return syms.errType;
215 }
216 log.error(pos, "type.found.req", found, required);
217 return types.createErrorType(found instanceof Type ? (Type)found : syms.errType);
218 }
220 /** Report an error that symbol cannot be referenced before super
221 * has been called.
222 * @param pos Position to be used for error reporting.
223 * @param sym The referenced symbol.
224 */
225 void earlyRefError(DiagnosticPosition pos, Symbol sym) {
226 log.error(pos, "cant.ref.before.ctor.called", sym);
227 }
229 /** Report duplicate declaration error.
230 */
231 void duplicateError(DiagnosticPosition pos, Symbol sym) {
232 if (!sym.type.isErroneous()) {
233 log.error(pos, "already.defined", sym, sym.location());
234 }
235 }
237 /** Report array/varargs duplicate declaration
238 */
239 void varargsDuplicateError(DiagnosticPosition pos, Symbol sym1, Symbol sym2) {
240 if (!sym1.type.isErroneous() && !sym2.type.isErroneous()) {
241 log.error(pos, "array.and.varargs", sym1, sym2, sym2.location());
242 }
243 }
245 /* ************************************************************************
246 * duplicate declaration checking
247 *************************************************************************/
249 /** Check that variable does not hide variable with same name in
250 * immediately enclosing local scope.
251 * @param pos Position for error reporting.
252 * @param v The symbol.
253 * @param s The scope.
254 */
255 void checkTransparentVar(DiagnosticPosition pos, VarSymbol v, Scope s) {
256 if (s.next != null) {
257 for (Scope.Entry e = s.next.lookup(v.name);
258 e.scope != null && e.sym.owner == v.owner;
259 e = e.next()) {
260 if (e.sym.kind == VAR &&
261 (e.sym.owner.kind & (VAR | MTH)) != 0 &&
262 v.name != names.error) {
263 duplicateError(pos, e.sym);
264 return;
265 }
266 }
267 }
268 }
270 /** Check that a class or interface does not hide a class or
271 * interface with same name in immediately enclosing local scope.
272 * @param pos Position for error reporting.
273 * @param c The symbol.
274 * @param s The scope.
275 */
276 void checkTransparentClass(DiagnosticPosition pos, ClassSymbol c, Scope s) {
277 if (s.next != null) {
278 for (Scope.Entry e = s.next.lookup(c.name);
279 e.scope != null && e.sym.owner == c.owner;
280 e = e.next()) {
281 if (e.sym.kind == TYP &&
282 (e.sym.owner.kind & (VAR | MTH)) != 0 &&
283 c.name != names.error) {
284 duplicateError(pos, e.sym);
285 return;
286 }
287 }
288 }
289 }
291 /** Check that class does not have the same name as one of
292 * its enclosing classes, or as a class defined in its enclosing scope.
293 * return true if class is unique in its enclosing scope.
294 * @param pos Position for error reporting.
295 * @param name The class name.
296 * @param s The enclosing scope.
297 */
298 boolean checkUniqueClassName(DiagnosticPosition pos, Name name, Scope s) {
299 for (Scope.Entry e = s.lookup(name); e.scope == s; e = e.next()) {
300 if (e.sym.kind == TYP && e.sym.name != names.error) {
301 duplicateError(pos, e.sym);
302 return false;
303 }
304 }
305 for (Symbol sym = s.owner; sym != null; sym = sym.owner) {
306 if (sym.kind == TYP && sym.name == name && sym.name != names.error) {
307 duplicateError(pos, sym);
308 return true;
309 }
310 }
311 return true;
312 }
314 /* *************************************************************************
315 * Class name generation
316 **************************************************************************/
318 /** Return name of local class.
319 * This is of the form <enclClass> $ n <classname>
320 * where
321 * enclClass is the flat name of the enclosing class,
322 * classname is the simple name of the local class
323 */
324 Name localClassName(ClassSymbol c) {
325 for (int i=1; ; i++) {
326 Name flatname = names.
327 fromString("" + c.owner.enclClass().flatname +
328 target.syntheticNameChar() + i +
329 c.name);
330 if (compiled.get(flatname) == null) return flatname;
331 }
332 }
334 /* *************************************************************************
335 * Type Checking
336 **************************************************************************/
338 /** Check that a given type is assignable to a given proto-type.
339 * If it is, return the type, otherwise return errType.
340 * @param pos Position to be used for error reporting.
341 * @param found The type that was found.
342 * @param req The type that was required.
343 */
344 Type checkType(DiagnosticPosition pos, Type found, Type req) {
345 if (req.tag == ERROR)
346 return req;
347 if (found.tag == FORALL)
348 return instantiatePoly(pos, (ForAll)found, req, convertWarner(pos, found, req));
349 if (req.tag == NONE)
350 return found;
351 if (types.isAssignable(found, req, convertWarner(pos, found, req)))
352 return found;
353 if (found.tag <= DOUBLE && req.tag <= DOUBLE)
354 return typeError(pos, diags.fragment("possible.loss.of.precision"), found, req);
355 if (found.isSuperBound()) {
356 log.error(pos, "assignment.from.super-bound", found);
357 return types.createErrorType(found);
358 }
359 if (req.isExtendsBound()) {
360 log.error(pos, "assignment.to.extends-bound", req);
361 return types.createErrorType(found);
362 }
363 return typeError(pos, diags.fragment("incompatible.types"), found, req);
364 }
366 /** Instantiate polymorphic type to some prototype, unless
367 * prototype is `anyPoly' in which case polymorphic type
368 * is returned unchanged.
369 */
370 Type instantiatePoly(DiagnosticPosition pos, ForAll t, Type pt, Warner warn) {
371 if (pt == Infer.anyPoly && complexInference) {
372 return t;
373 } else if (pt == Infer.anyPoly || pt.tag == NONE) {
374 Type newpt = t.qtype.tag <= VOID ? t.qtype : syms.objectType;
375 return instantiatePoly(pos, t, newpt, warn);
376 } else if (pt.tag == ERROR) {
377 return pt;
378 } else {
379 try {
380 return infer.instantiateExpr(t, pt, warn);
381 } catch (Infer.NoInstanceException ex) {
382 if (ex.isAmbiguous) {
383 JCDiagnostic d = ex.getDiagnostic();
384 log.error(pos,
385 "undetermined.type" + (d!=null ? ".1" : ""),
386 t, d);
387 return types.createErrorType(pt);
388 } else {
389 JCDiagnostic d = ex.getDiagnostic();
390 return typeError(pos,
391 diags.fragment("incompatible.types" + (d!=null ? ".1" : ""), d),
392 t, pt);
393 }
394 }
395 }
396 }
398 /** Check that a given type can be cast to a given target type.
399 * Return the result of the cast.
400 * @param pos Position to be used for error reporting.
401 * @param found The type that is being cast.
402 * @param req The target type of the cast.
403 */
404 Type checkCastable(DiagnosticPosition pos, Type found, Type req) {
405 if (found.tag == FORALL) {
406 instantiatePoly(pos, (ForAll) found, req, castWarner(pos, found, req));
407 return req;
408 } else if (types.isCastable(found, req, castWarner(pos, found, req))) {
409 return req;
410 } else {
411 return typeError(pos,
412 diags.fragment("inconvertible.types"),
413 found, req);
414 }
415 }
416 //where
417 /** Is type a type variable, or a (possibly multi-dimensional) array of
418 * type variables?
419 */
420 boolean isTypeVar(Type t) {
421 return t.tag == TYPEVAR || t.tag == ARRAY && isTypeVar(types.elemtype(t));
422 }
424 /** Check that a type is within some bounds.
425 *
426 * Used in TypeApply to verify that, e.g., X in V<X> is a valid
427 * type argument.
428 * @param pos Position to be used for error reporting.
429 * @param a The type that should be bounded by bs.
430 * @param bs The bound.
431 */
432 private void checkExtends(DiagnosticPosition pos, Type a, TypeVar bs) {
433 if (a.isUnbound()) {
434 return;
435 } else if (a.tag != WILDCARD) {
436 a = types.upperBound(a);
437 for (List<Type> l = types.getBounds(bs); l.nonEmpty(); l = l.tail) {
438 if (!types.isSubtype(a, l.head)) {
439 log.error(pos, "not.within.bounds", a);
440 return;
441 }
442 }
443 } else if (a.isExtendsBound()) {
444 if (!types.isCastable(bs.getUpperBound(), types.upperBound(a), Warner.noWarnings))
445 log.error(pos, "not.within.bounds", a);
446 } else if (a.isSuperBound()) {
447 if (types.notSoftSubtype(types.lowerBound(a), bs.getUpperBound()))
448 log.error(pos, "not.within.bounds", a);
449 }
450 }
452 /** Check that a type is within some bounds.
453 *
454 * Used in TypeApply to verify that, e.g., X in V<X> is a valid
455 * type argument.
456 * @param pos Position to be used for error reporting.
457 * @param a The type that should be bounded by bs.
458 * @param bs The bound.
459 */
460 private void checkCapture(JCTypeApply tree) {
461 List<JCExpression> args = tree.getTypeArguments();
462 for (Type arg : types.capture(tree.type).getTypeArguments()) {
463 if (arg.tag == TYPEVAR && arg.getUpperBound().isErroneous()) {
464 log.error(args.head.pos, "not.within.bounds", args.head.type);
465 break;
466 }
467 args = args.tail;
468 }
469 }
471 /** Check that type is different from 'void'.
472 * @param pos Position to be used for error reporting.
473 * @param t The type to be checked.
474 */
475 Type checkNonVoid(DiagnosticPosition pos, Type t) {
476 if (t.tag == VOID) {
477 log.error(pos, "void.not.allowed.here");
478 return types.createErrorType(t);
479 } else {
480 return t;
481 }
482 }
484 /** Check that type is a class or interface type.
485 * @param pos Position to be used for error reporting.
486 * @param t The type to be checked.
487 */
488 Type checkClassType(DiagnosticPosition pos, Type t) {
489 if (t.tag != CLASS && t.tag != ERROR)
490 return typeTagError(pos,
491 diags.fragment("type.req.class"),
492 (t.tag == TYPEVAR)
493 ? diags.fragment("type.parameter", t)
494 : t);
495 else
496 return t;
497 }
499 /** Check that type is a class or interface type.
500 * @param pos Position to be used for error reporting.
501 * @param t The type to be checked.
502 * @param noBounds True if type bounds are illegal here.
503 */
504 Type checkClassType(DiagnosticPosition pos, Type t, boolean noBounds) {
505 t = checkClassType(pos, t);
506 if (noBounds && t.isParameterized()) {
507 List<Type> args = t.getTypeArguments();
508 while (args.nonEmpty()) {
509 if (args.head.tag == WILDCARD)
510 return typeTagError(pos,
511 log.getLocalizedString("type.req.exact"),
512 args.head);
513 args = args.tail;
514 }
515 }
516 return t;
517 }
519 /** Check that type is a reifiable class, interface or array type.
520 * @param pos Position to be used for error reporting.
521 * @param t The type to be checked.
522 */
523 Type checkReifiableReferenceType(DiagnosticPosition pos, Type t) {
524 if (t.tag != CLASS && t.tag != ARRAY && t.tag != ERROR) {
525 return typeTagError(pos,
526 diags.fragment("type.req.class.array"),
527 t);
528 } else if (!types.isReifiable(t)) {
529 log.error(pos, "illegal.generic.type.for.instof");
530 return types.createErrorType(t);
531 } else {
532 return t;
533 }
534 }
536 /** Check that type is a reference type, i.e. a class, interface or array type
537 * or a type variable.
538 * @param pos Position to be used for error reporting.
539 * @param t The type to be checked.
540 */
541 Type checkRefType(DiagnosticPosition pos, Type t) {
542 switch (t.tag) {
543 case CLASS:
544 case ARRAY:
545 case TYPEVAR:
546 case WILDCARD:
547 case ERROR:
548 return t;
549 default:
550 return typeTagError(pos,
551 diags.fragment("type.req.ref"),
552 t);
553 }
554 }
556 /** Check that each type is a reference type, i.e. a class, interface or array type
557 * or a type variable.
558 * @param trees Original trees, used for error reporting.
559 * @param types The types to be checked.
560 */
561 List<Type> checkRefTypes(List<JCExpression> trees, List<Type> types) {
562 List<JCExpression> tl = trees;
563 for (List<Type> l = types; l.nonEmpty(); l = l.tail) {
564 l.head = checkRefType(tl.head.pos(), l.head);
565 tl = tl.tail;
566 }
567 return types;
568 }
570 /** Check that type is a null or reference type.
571 * @param pos Position to be used for error reporting.
572 * @param t The type to be checked.
573 */
574 Type checkNullOrRefType(DiagnosticPosition pos, Type t) {
575 switch (t.tag) {
576 case CLASS:
577 case ARRAY:
578 case TYPEVAR:
579 case WILDCARD:
580 case BOT:
581 case ERROR:
582 return t;
583 default:
584 return typeTagError(pos,
585 diags.fragment("type.req.ref"),
586 t);
587 }
588 }
590 /** Check that flag set does not contain elements of two conflicting sets. s
591 * Return true if it doesn't.
592 * @param pos Position to be used for error reporting.
593 * @param flags The set of flags to be checked.
594 * @param set1 Conflicting flags set #1.
595 * @param set2 Conflicting flags set #2.
596 */
597 boolean checkDisjoint(DiagnosticPosition pos, long flags, long set1, long set2) {
598 if ((flags & set1) != 0 && (flags & set2) != 0) {
599 log.error(pos,
600 "illegal.combination.of.modifiers",
601 asFlagSet(TreeInfo.firstFlag(flags & set1)),
602 asFlagSet(TreeInfo.firstFlag(flags & set2)));
603 return false;
604 } else
605 return true;
606 }
608 /** Check that given modifiers are legal for given symbol and
609 * return modifiers together with any implicit modififiers for that symbol.
610 * Warning: we can't use flags() here since this method
611 * is called during class enter, when flags() would cause a premature
612 * completion.
613 * @param pos Position to be used for error reporting.
614 * @param flags The set of modifiers given in a definition.
615 * @param sym The defined symbol.
616 */
617 long checkFlags(DiagnosticPosition pos, long flags, Symbol sym, JCTree tree) {
618 long mask;
619 long implicit = 0;
620 switch (sym.kind) {
621 case VAR:
622 if (sym.owner.kind != TYP)
623 mask = LocalVarFlags;
624 else if ((sym.owner.flags_field & INTERFACE) != 0)
625 mask = implicit = InterfaceVarFlags;
626 else
627 mask = VarFlags;
628 break;
629 case MTH:
630 if (sym.name == names.init) {
631 if ((sym.owner.flags_field & ENUM) != 0) {
632 // enum constructors cannot be declared public or
633 // protected and must be implicitly or explicitly
634 // private
635 implicit = PRIVATE;
636 mask = PRIVATE;
637 } else
638 mask = ConstructorFlags;
639 } else if ((sym.owner.flags_field & INTERFACE) != 0)
640 mask = implicit = InterfaceMethodFlags;
641 else {
642 mask = MethodFlags;
643 }
644 // Imply STRICTFP if owner has STRICTFP set.
645 if (((flags|implicit) & Flags.ABSTRACT) == 0)
646 implicit |= sym.owner.flags_field & STRICTFP;
647 break;
648 case TYP:
649 if (sym.isLocal()) {
650 mask = LocalClassFlags;
651 if (sym.name.isEmpty()) { // Anonymous class
652 // Anonymous classes in static methods are themselves static;
653 // that's why we admit STATIC here.
654 mask |= STATIC;
655 // JLS: Anonymous classes are final.
656 implicit |= FINAL;
657 }
658 if ((sym.owner.flags_field & STATIC) == 0 &&
659 (flags & ENUM) != 0)
660 log.error(pos, "enums.must.be.static");
661 } else if (sym.owner.kind == TYP) {
662 mask = MemberClassFlags;
663 if (sym.owner.owner.kind == PCK ||
664 (sym.owner.flags_field & STATIC) != 0)
665 mask |= STATIC;
666 else if ((flags & ENUM) != 0)
667 log.error(pos, "enums.must.be.static");
668 // Nested interfaces and enums are always STATIC (Spec ???)
669 if ((flags & (INTERFACE | ENUM)) != 0 ) implicit = STATIC;
670 } else {
671 mask = ClassFlags;
672 }
673 // Interfaces are always ABSTRACT
674 if ((flags & INTERFACE) != 0) implicit |= ABSTRACT;
676 if ((flags & ENUM) != 0) {
677 // enums can't be declared abstract or final
678 mask &= ~(ABSTRACT | FINAL);
679 implicit |= implicitEnumFinalFlag(tree);
680 }
681 // Imply STRICTFP if owner has STRICTFP set.
682 implicit |= sym.owner.flags_field & STRICTFP;
683 break;
684 default:
685 throw new AssertionError();
686 }
687 long illegal = flags & StandardFlags & ~mask;
688 if (illegal != 0) {
689 if ((illegal & INTERFACE) != 0) {
690 log.error(pos, "intf.not.allowed.here");
691 mask |= INTERFACE;
692 }
693 else {
694 log.error(pos,
695 "mod.not.allowed.here", asFlagSet(illegal));
696 }
697 }
698 else if ((sym.kind == TYP ||
699 // ISSUE: Disallowing abstract&private is no longer appropriate
700 // in the presence of inner classes. Should it be deleted here?
701 checkDisjoint(pos, flags,
702 ABSTRACT,
703 PRIVATE | STATIC))
704 &&
705 checkDisjoint(pos, flags,
706 ABSTRACT | INTERFACE,
707 FINAL | NATIVE | SYNCHRONIZED)
708 &&
709 checkDisjoint(pos, flags,
710 PUBLIC,
711 PRIVATE | PROTECTED)
712 &&
713 checkDisjoint(pos, flags,
714 PRIVATE,
715 PUBLIC | PROTECTED)
716 &&
717 checkDisjoint(pos, flags,
718 FINAL,
719 VOLATILE)
720 &&
721 (sym.kind == TYP ||
722 checkDisjoint(pos, flags,
723 ABSTRACT | NATIVE,
724 STRICTFP))) {
725 // skip
726 }
727 return flags & (mask | ~StandardFlags) | implicit;
728 }
731 /** Determine if this enum should be implicitly final.
732 *
733 * If the enum has no specialized enum contants, it is final.
734 *
735 * If the enum does have specialized enum contants, it is
736 * <i>not</i> final.
737 */
738 private long implicitEnumFinalFlag(JCTree tree) {
739 if (tree.getTag() != JCTree.CLASSDEF) return 0;
740 class SpecialTreeVisitor extends JCTree.Visitor {
741 boolean specialized;
742 SpecialTreeVisitor() {
743 this.specialized = false;
744 };
746 public void visitTree(JCTree tree) { /* no-op */ }
748 public void visitVarDef(JCVariableDecl tree) {
749 if ((tree.mods.flags & ENUM) != 0) {
750 if (tree.init instanceof JCNewClass &&
751 ((JCNewClass) tree.init).def != null) {
752 specialized = true;
753 }
754 }
755 }
756 }
758 SpecialTreeVisitor sts = new SpecialTreeVisitor();
759 JCClassDecl cdef = (JCClassDecl) tree;
760 for (JCTree defs: cdef.defs) {
761 defs.accept(sts);
762 if (sts.specialized) return 0;
763 }
764 return FINAL;
765 }
767 /* *************************************************************************
768 * Type Validation
769 **************************************************************************/
771 /** Validate a type expression. That is,
772 * check that all type arguments of a parametric type are within
773 * their bounds. This must be done in a second phase after type attributon
774 * since a class might have a subclass as type parameter bound. E.g:
775 *
776 * class B<A extends C> { ... }
777 * class C extends B<C> { ... }
778 *
779 * and we can't make sure that the bound is already attributed because
780 * of possible cycles.
781 */
782 private Validator validator = new Validator();
784 /** Visitor method: Validate a type expression, if it is not null, catching
785 * and reporting any completion failures.
786 */
787 void validate(JCTree tree, Env<AttrContext> env) {
788 try {
789 if (tree != null) {
790 validator.env = env;
791 tree.accept(validator);
792 checkRaw(tree, env);
793 }
794 } catch (CompletionFailure ex) {
795 completionError(tree.pos(), ex);
796 }
797 }
798 //where
799 void checkRaw(JCTree tree, Env<AttrContext> env) {
800 if (lint.isEnabled(Lint.LintCategory.RAW) &&
801 tree.type.tag == CLASS &&
802 !env.enclClass.name.isEmpty() && //anonymous or intersection
803 tree.type.isRaw()) {
804 log.warning(tree.pos(), "raw.class.use", tree.type, tree.type.tsym.type);
805 }
806 }
808 /** Visitor method: Validate a list of type expressions.
809 */
810 void validate(List<? extends JCTree> trees, Env<AttrContext> env) {
811 for (List<? extends JCTree> l = trees; l.nonEmpty(); l = l.tail)
812 validate(l.head, env);
813 }
815 /** A visitor class for type validation.
816 */
817 class Validator extends JCTree.Visitor {
819 public void visitTypeArray(JCArrayTypeTree tree) {
820 validate(tree.elemtype, env);
821 }
823 public void visitTypeApply(JCTypeApply tree) {
824 if (tree.type.tag == CLASS) {
825 List<Type> formals = tree.type.tsym.type.allparams();
826 List<Type> actuals = tree.type.allparams();
827 List<JCExpression> args = tree.arguments;
828 List<Type> forms = tree.type.tsym.type.getTypeArguments();
829 ListBuffer<TypeVar> tvars_buf = new ListBuffer<TypeVar>();
831 // For matching pairs of actual argument types `a' and
832 // formal type parameters with declared bound `b' ...
833 while (args.nonEmpty() && forms.nonEmpty()) {
834 validate(args.head, env);
836 // exact type arguments needs to know their
837 // bounds (for upper and lower bound
838 // calculations). So we create new TypeVars with
839 // bounds substed with actuals.
840 tvars_buf.append(types.substBound(((TypeVar)forms.head),
841 formals,
842 actuals));
844 args = args.tail;
845 forms = forms.tail;
846 }
848 args = tree.arguments;
849 List<Type> tvars_cap = types.substBounds(formals,
850 formals,
851 types.capture(tree.type).allparams());
852 while (args.nonEmpty() && tvars_cap.nonEmpty()) {
853 // Let the actual arguments know their bound
854 args.head.type.withTypeVar((TypeVar)tvars_cap.head);
855 args = args.tail;
856 tvars_cap = tvars_cap.tail;
857 }
859 args = tree.arguments;
860 List<TypeVar> tvars = tvars_buf.toList();
862 while (args.nonEmpty() && tvars.nonEmpty()) {
863 checkExtends(args.head.pos(),
864 args.head.type,
865 tvars.head);
866 args = args.tail;
867 tvars = tvars.tail;
868 }
870 checkCapture(tree);
872 // Check that this type is either fully parameterized, or
873 // not parameterized at all.
874 if (tree.type.getEnclosingType().isRaw())
875 log.error(tree.pos(), "improperly.formed.type.inner.raw.param");
876 if (tree.clazz.getTag() == JCTree.SELECT)
877 visitSelectInternal((JCFieldAccess)tree.clazz);
878 }
879 }
881 public void visitTypeParameter(JCTypeParameter tree) {
882 validate(tree.bounds, env);
883 checkClassBounds(tree.pos(), tree.type);
884 }
886 @Override
887 public void visitWildcard(JCWildcard tree) {
888 if (tree.inner != null)
889 validate(tree.inner, env);
890 }
892 public void visitSelect(JCFieldAccess tree) {
893 if (tree.type.tag == CLASS) {
894 visitSelectInternal(tree);
896 // Check that this type is either fully parameterized, or
897 // not parameterized at all.
898 if (tree.selected.type.isParameterized() && tree.type.tsym.type.getTypeArguments().nonEmpty())
899 log.error(tree.pos(), "improperly.formed.type.param.missing");
900 }
901 }
902 public void visitSelectInternal(JCFieldAccess tree) {
903 if (tree.type.tsym.isStatic() &&
904 tree.selected.type.isParameterized()) {
905 // The enclosing type is not a class, so we are
906 // looking at a static member type. However, the
907 // qualifying expression is parameterized.
908 log.error(tree.pos(), "cant.select.static.class.from.param.type");
909 } else {
910 // otherwise validate the rest of the expression
911 tree.selected.accept(this);
912 }
913 }
915 /** Default visitor method: do nothing.
916 */
917 public void visitTree(JCTree tree) {
918 }
920 Env<AttrContext> env;
921 }
923 /* *************************************************************************
924 * Exception checking
925 **************************************************************************/
927 /* The following methods treat classes as sets that contain
928 * the class itself and all their subclasses
929 */
931 /** Is given type a subtype of some of the types in given list?
932 */
933 boolean subset(Type t, List<Type> ts) {
934 for (List<Type> l = ts; l.nonEmpty(); l = l.tail)
935 if (types.isSubtype(t, l.head)) return true;
936 return false;
937 }
939 /** Is given type a subtype or supertype of
940 * some of the types in given list?
941 */
942 boolean intersects(Type t, List<Type> ts) {
943 for (List<Type> l = ts; l.nonEmpty(); l = l.tail)
944 if (types.isSubtype(t, l.head) || types.isSubtype(l.head, t)) return true;
945 return false;
946 }
948 /** Add type set to given type list, unless it is a subclass of some class
949 * in the list.
950 */
951 List<Type> incl(Type t, List<Type> ts) {
952 return subset(t, ts) ? ts : excl(t, ts).prepend(t);
953 }
955 /** Remove type set from type set list.
956 */
957 List<Type> excl(Type t, List<Type> ts) {
958 if (ts.isEmpty()) {
959 return ts;
960 } else {
961 List<Type> ts1 = excl(t, ts.tail);
962 if (types.isSubtype(ts.head, t)) return ts1;
963 else if (ts1 == ts.tail) return ts;
964 else return ts1.prepend(ts.head);
965 }
966 }
968 /** Form the union of two type set lists.
969 */
970 List<Type> union(List<Type> ts1, List<Type> ts2) {
971 List<Type> ts = ts1;
972 for (List<Type> l = ts2; l.nonEmpty(); l = l.tail)
973 ts = incl(l.head, ts);
974 return ts;
975 }
977 /** Form the difference of two type lists.
978 */
979 List<Type> diff(List<Type> ts1, List<Type> ts2) {
980 List<Type> ts = ts1;
981 for (List<Type> l = ts2; l.nonEmpty(); l = l.tail)
982 ts = excl(l.head, ts);
983 return ts;
984 }
986 /** Form the intersection of two type lists.
987 */
988 public List<Type> intersect(List<Type> ts1, List<Type> ts2) {
989 List<Type> ts = List.nil();
990 for (List<Type> l = ts1; l.nonEmpty(); l = l.tail)
991 if (subset(l.head, ts2)) ts = incl(l.head, ts);
992 for (List<Type> l = ts2; l.nonEmpty(); l = l.tail)
993 if (subset(l.head, ts1)) ts = incl(l.head, ts);
994 return ts;
995 }
997 /** Is exc an exception symbol that need not be declared?
998 */
999 boolean isUnchecked(ClassSymbol exc) {
1000 return
1001 exc.kind == ERR ||
1002 exc.isSubClass(syms.errorType.tsym, types) ||
1003 exc.isSubClass(syms.runtimeExceptionType.tsym, types);
1004 }
1006 /** Is exc an exception type that need not be declared?
1007 */
1008 boolean isUnchecked(Type exc) {
1009 return
1010 (exc.tag == TYPEVAR) ? isUnchecked(types.supertype(exc)) :
1011 (exc.tag == CLASS) ? isUnchecked((ClassSymbol)exc.tsym) :
1012 exc.tag == BOT;
1013 }
1015 /** Same, but handling completion failures.
1016 */
1017 boolean isUnchecked(DiagnosticPosition pos, Type exc) {
1018 try {
1019 return isUnchecked(exc);
1020 } catch (CompletionFailure ex) {
1021 completionError(pos, ex);
1022 return true;
1023 }
1024 }
1026 /** Is exc handled by given exception list?
1027 */
1028 boolean isHandled(Type exc, List<Type> handled) {
1029 return isUnchecked(exc) || subset(exc, handled);
1030 }
1032 /** Return all exceptions in thrown list that are not in handled list.
1033 * @param thrown The list of thrown exceptions.
1034 * @param handled The list of handled exceptions.
1035 */
1036 List<Type> unHandled(List<Type> thrown, List<Type> handled) {
1037 List<Type> unhandled = List.nil();
1038 for (List<Type> l = thrown; l.nonEmpty(); l = l.tail)
1039 if (!isHandled(l.head, handled)) unhandled = unhandled.prepend(l.head);
1040 return unhandled;
1041 }
1043 /* *************************************************************************
1044 * Overriding/Implementation checking
1045 **************************************************************************/
1047 /** The level of access protection given by a flag set,
1048 * where PRIVATE is highest and PUBLIC is lowest.
1049 */
1050 static int protection(long flags) {
1051 switch ((short)(flags & AccessFlags)) {
1052 case PRIVATE: return 3;
1053 case PROTECTED: return 1;
1054 default:
1055 case PUBLIC: return 0;
1056 case 0: return 2;
1057 }
1058 }
1060 /** A customized "cannot override" error message.
1061 * @param m The overriding method.
1062 * @param other The overridden method.
1063 * @return An internationalized string.
1064 */
1065 Object cannotOverride(MethodSymbol m, MethodSymbol other) {
1066 String key;
1067 if ((other.owner.flags() & INTERFACE) == 0)
1068 key = "cant.override";
1069 else if ((m.owner.flags() & INTERFACE) == 0)
1070 key = "cant.implement";
1071 else
1072 key = "clashes.with";
1073 return diags.fragment(key, m, m.location(), other, other.location());
1074 }
1076 /** A customized "override" warning message.
1077 * @param m The overriding method.
1078 * @param other The overridden method.
1079 * @return An internationalized string.
1080 */
1081 Object uncheckedOverrides(MethodSymbol m, MethodSymbol other) {
1082 String key;
1083 if ((other.owner.flags() & INTERFACE) == 0)
1084 key = "unchecked.override";
1085 else if ((m.owner.flags() & INTERFACE) == 0)
1086 key = "unchecked.implement";
1087 else
1088 key = "unchecked.clash.with";
1089 return diags.fragment(key, m, m.location(), other, other.location());
1090 }
1092 /** A customized "override" warning message.
1093 * @param m The overriding method.
1094 * @param other The overridden method.
1095 * @return An internationalized string.
1096 */
1097 Object varargsOverrides(MethodSymbol m, MethodSymbol other) {
1098 String key;
1099 if ((other.owner.flags() & INTERFACE) == 0)
1100 key = "varargs.override";
1101 else if ((m.owner.flags() & INTERFACE) == 0)
1102 key = "varargs.implement";
1103 else
1104 key = "varargs.clash.with";
1105 return diags.fragment(key, m, m.location(), other, other.location());
1106 }
1108 /** Check that this method conforms with overridden method 'other'.
1109 * where `origin' is the class where checking started.
1110 * Complications:
1111 * (1) Do not check overriding of synthetic methods
1112 * (reason: they might be final).
1113 * todo: check whether this is still necessary.
1114 * (2) Admit the case where an interface proxy throws fewer exceptions
1115 * than the method it implements. Augment the proxy methods with the
1116 * undeclared exceptions in this case.
1117 * (3) When generics are enabled, admit the case where an interface proxy
1118 * has a result type
1119 * extended by the result type of the method it implements.
1120 * Change the proxies result type to the smaller type in this case.
1121 *
1122 * @param tree The tree from which positions
1123 * are extracted for errors.
1124 * @param m The overriding method.
1125 * @param other The overridden method.
1126 * @param origin The class of which the overriding method
1127 * is a member.
1128 */
1129 void checkOverride(JCTree tree,
1130 MethodSymbol m,
1131 MethodSymbol other,
1132 ClassSymbol origin) {
1133 // Don't check overriding of synthetic methods or by bridge methods.
1134 if ((m.flags() & (SYNTHETIC|BRIDGE)) != 0 || (other.flags() & SYNTHETIC) != 0) {
1135 return;
1136 }
1138 // Error if static method overrides instance method (JLS 8.4.6.2).
1139 if ((m.flags() & STATIC) != 0 &&
1140 (other.flags() & STATIC) == 0) {
1141 log.error(TreeInfo.diagnosticPositionFor(m, tree), "override.static",
1142 cannotOverride(m, other));
1143 return;
1144 }
1146 // Error if instance method overrides static or final
1147 // method (JLS 8.4.6.1).
1148 if ((other.flags() & FINAL) != 0 ||
1149 (m.flags() & STATIC) == 0 &&
1150 (other.flags() & STATIC) != 0) {
1151 log.error(TreeInfo.diagnosticPositionFor(m, tree), "override.meth",
1152 cannotOverride(m, other),
1153 asFlagSet(other.flags() & (FINAL | STATIC)));
1154 return;
1155 }
1157 if ((m.owner.flags() & ANNOTATION) != 0) {
1158 // handled in validateAnnotationMethod
1159 return;
1160 }
1162 // Error if overriding method has weaker access (JLS 8.4.6.3).
1163 if ((origin.flags() & INTERFACE) == 0 &&
1164 protection(m.flags()) > protection(other.flags())) {
1165 log.error(TreeInfo.diagnosticPositionFor(m, tree), "override.weaker.access",
1166 cannotOverride(m, other),
1167 other.flags() == 0 ?
1168 Flag.PACKAGE :
1169 asFlagSet(other.flags() & AccessFlags));
1170 return;
1171 }
1173 Type mt = types.memberType(origin.type, m);
1174 Type ot = types.memberType(origin.type, other);
1175 // Error if overriding result type is different
1176 // (or, in the case of generics mode, not a subtype) of
1177 // overridden result type. We have to rename any type parameters
1178 // before comparing types.
1179 List<Type> mtvars = mt.getTypeArguments();
1180 List<Type> otvars = ot.getTypeArguments();
1181 Type mtres = mt.getReturnType();
1182 Type otres = types.subst(ot.getReturnType(), otvars, mtvars);
1184 overrideWarner.warned = false;
1185 boolean resultTypesOK =
1186 types.returnTypeSubstitutable(mt, ot, otres, overrideWarner);
1187 if (!resultTypesOK) {
1188 if (!source.allowCovariantReturns() &&
1189 m.owner != origin &&
1190 m.owner.isSubClass(other.owner, types)) {
1191 // allow limited interoperability with covariant returns
1192 } else {
1193 typeError(TreeInfo.diagnosticPositionFor(m, tree),
1194 diags.fragment("override.incompatible.ret",
1195 cannotOverride(m, other)),
1196 mtres, otres);
1197 return;
1198 }
1199 } else if (overrideWarner.warned) {
1200 warnUnchecked(TreeInfo.diagnosticPositionFor(m, tree),
1201 "prob.found.req",
1202 diags.fragment("override.unchecked.ret",
1203 uncheckedOverrides(m, other)),
1204 mtres, otres);
1205 }
1207 // Error if overriding method throws an exception not reported
1208 // by overridden method.
1209 List<Type> otthrown = types.subst(ot.getThrownTypes(), otvars, mtvars);
1210 List<Type> unhandled = unHandled(mt.getThrownTypes(), otthrown);
1211 if (unhandled.nonEmpty()) {
1212 log.error(TreeInfo.diagnosticPositionFor(m, tree),
1213 "override.meth.doesnt.throw",
1214 cannotOverride(m, other),
1215 unhandled.head);
1216 return;
1217 }
1219 // Optional warning if varargs don't agree
1220 if ((((m.flags() ^ other.flags()) & Flags.VARARGS) != 0)
1221 && lint.isEnabled(Lint.LintCategory.OVERRIDES)) {
1222 log.warning(TreeInfo.diagnosticPositionFor(m, tree),
1223 ((m.flags() & Flags.VARARGS) != 0)
1224 ? "override.varargs.missing"
1225 : "override.varargs.extra",
1226 varargsOverrides(m, other));
1227 }
1229 // Warn if instance method overrides bridge method (compiler spec ??)
1230 if ((other.flags() & BRIDGE) != 0) {
1231 log.warning(TreeInfo.diagnosticPositionFor(m, tree), "override.bridge",
1232 uncheckedOverrides(m, other));
1233 }
1235 // Warn if a deprecated method overridden by a non-deprecated one.
1236 if ((other.flags() & DEPRECATED) != 0
1237 && (m.flags() & DEPRECATED) == 0
1238 && m.outermostClass() != other.outermostClass()
1239 && !isDeprecatedOverrideIgnorable(other, origin)) {
1240 warnDeprecated(TreeInfo.diagnosticPositionFor(m, tree), other);
1241 }
1242 }
1243 // where
1244 private boolean isDeprecatedOverrideIgnorable(MethodSymbol m, ClassSymbol origin) {
1245 // If the method, m, is defined in an interface, then ignore the issue if the method
1246 // is only inherited via a supertype and also implemented in the supertype,
1247 // because in that case, we will rediscover the issue when examining the method
1248 // in the supertype.
1249 // If the method, m, is not defined in an interface, then the only time we need to
1250 // address the issue is when the method is the supertype implemementation: any other
1251 // case, we will have dealt with when examining the supertype classes
1252 ClassSymbol mc = m.enclClass();
1253 Type st = types.supertype(origin.type);
1254 if (st.tag != CLASS)
1255 return true;
1256 MethodSymbol stimpl = m.implementation((ClassSymbol)st.tsym, types, false);
1258 if (mc != null && ((mc.flags() & INTERFACE) != 0)) {
1259 List<Type> intfs = types.interfaces(origin.type);
1260 return (intfs.contains(mc.type) ? false : (stimpl != null));
1261 }
1262 else
1263 return (stimpl != m);
1264 }
1267 // used to check if there were any unchecked conversions
1268 Warner overrideWarner = new Warner();
1270 /** Check that a class does not inherit two concrete methods
1271 * with the same signature.
1272 * @param pos Position to be used for error reporting.
1273 * @param site The class type to be checked.
1274 */
1275 public void checkCompatibleConcretes(DiagnosticPosition pos, Type site) {
1276 Type sup = types.supertype(site);
1277 if (sup.tag != CLASS) return;
1279 for (Type t1 = sup;
1280 t1.tsym.type.isParameterized();
1281 t1 = types.supertype(t1)) {
1282 for (Scope.Entry e1 = t1.tsym.members().elems;
1283 e1 != null;
1284 e1 = e1.sibling) {
1285 Symbol s1 = e1.sym;
1286 if (s1.kind != MTH ||
1287 (s1.flags() & (STATIC|SYNTHETIC|BRIDGE)) != 0 ||
1288 !s1.isInheritedIn(site.tsym, types) ||
1289 ((MethodSymbol)s1).implementation(site.tsym,
1290 types,
1291 true) != s1)
1292 continue;
1293 Type st1 = types.memberType(t1, s1);
1294 int s1ArgsLength = st1.getParameterTypes().length();
1295 if (st1 == s1.type) continue;
1297 for (Type t2 = sup;
1298 t2.tag == CLASS;
1299 t2 = types.supertype(t2)) {
1300 for (Scope.Entry e2 = t2.tsym.members().lookup(s1.name);
1301 e2.scope != null;
1302 e2 = e2.next()) {
1303 Symbol s2 = e2.sym;
1304 if (s2 == s1 ||
1305 s2.kind != MTH ||
1306 (s2.flags() & (STATIC|SYNTHETIC|BRIDGE)) != 0 ||
1307 s2.type.getParameterTypes().length() != s1ArgsLength ||
1308 !s2.isInheritedIn(site.tsym, types) ||
1309 ((MethodSymbol)s2).implementation(site.tsym,
1310 types,
1311 true) != s2)
1312 continue;
1313 Type st2 = types.memberType(t2, s2);
1314 if (types.overrideEquivalent(st1, st2))
1315 log.error(pos, "concrete.inheritance.conflict",
1316 s1, t1, s2, t2, sup);
1317 }
1318 }
1319 }
1320 }
1321 }
1323 /** Check that classes (or interfaces) do not each define an abstract
1324 * method with same name and arguments but incompatible return types.
1325 * @param pos Position to be used for error reporting.
1326 * @param t1 The first argument type.
1327 * @param t2 The second argument type.
1328 */
1329 public boolean checkCompatibleAbstracts(DiagnosticPosition pos,
1330 Type t1,
1331 Type t2) {
1332 return checkCompatibleAbstracts(pos, t1, t2,
1333 types.makeCompoundType(t1, t2));
1334 }
1336 public boolean checkCompatibleAbstracts(DiagnosticPosition pos,
1337 Type t1,
1338 Type t2,
1339 Type site) {
1340 Symbol sym = firstIncompatibility(t1, t2, site);
1341 if (sym != null) {
1342 log.error(pos, "types.incompatible.diff.ret",
1343 t1, t2, sym.name +
1344 "(" + types.memberType(t2, sym).getParameterTypes() + ")");
1345 return false;
1346 }
1347 return true;
1348 }
1350 /** Return the first method which is defined with same args
1351 * but different return types in two given interfaces, or null if none
1352 * exists.
1353 * @param t1 The first type.
1354 * @param t2 The second type.
1355 * @param site The most derived type.
1356 * @returns symbol from t2 that conflicts with one in t1.
1357 */
1358 private Symbol firstIncompatibility(Type t1, Type t2, Type site) {
1359 Map<TypeSymbol,Type> interfaces1 = new HashMap<TypeSymbol,Type>();
1360 closure(t1, interfaces1);
1361 Map<TypeSymbol,Type> interfaces2;
1362 if (t1 == t2)
1363 interfaces2 = interfaces1;
1364 else
1365 closure(t2, interfaces1, interfaces2 = new HashMap<TypeSymbol,Type>());
1367 for (Type t3 : interfaces1.values()) {
1368 for (Type t4 : interfaces2.values()) {
1369 Symbol s = firstDirectIncompatibility(t3, t4, site);
1370 if (s != null) return s;
1371 }
1372 }
1373 return null;
1374 }
1376 /** Compute all the supertypes of t, indexed by type symbol. */
1377 private void closure(Type t, Map<TypeSymbol,Type> typeMap) {
1378 if (t.tag != CLASS) return;
1379 if (typeMap.put(t.tsym, t) == null) {
1380 closure(types.supertype(t), typeMap);
1381 for (Type i : types.interfaces(t))
1382 closure(i, typeMap);
1383 }
1384 }
1386 /** Compute all the supertypes of t, indexed by type symbol (except thise in typesSkip). */
1387 private void closure(Type t, Map<TypeSymbol,Type> typesSkip, Map<TypeSymbol,Type> typeMap) {
1388 if (t.tag != CLASS) return;
1389 if (typesSkip.get(t.tsym) != null) return;
1390 if (typeMap.put(t.tsym, t) == null) {
1391 closure(types.supertype(t), typesSkip, typeMap);
1392 for (Type i : types.interfaces(t))
1393 closure(i, typesSkip, typeMap);
1394 }
1395 }
1397 /** Return the first method in t2 that conflicts with a method from t1. */
1398 private Symbol firstDirectIncompatibility(Type t1, Type t2, Type site) {
1399 for (Scope.Entry e1 = t1.tsym.members().elems; e1 != null; e1 = e1.sibling) {
1400 Symbol s1 = e1.sym;
1401 Type st1 = null;
1402 if (s1.kind != MTH || !s1.isInheritedIn(site.tsym, types)) continue;
1403 Symbol impl = ((MethodSymbol)s1).implementation(site.tsym, types, false);
1404 if (impl != null && (impl.flags() & ABSTRACT) == 0) continue;
1405 for (Scope.Entry e2 = t2.tsym.members().lookup(s1.name); e2.scope != null; e2 = e2.next()) {
1406 Symbol s2 = e2.sym;
1407 if (s1 == s2) continue;
1408 if (s2.kind != MTH || !s2.isInheritedIn(site.tsym, types)) continue;
1409 if (st1 == null) st1 = types.memberType(t1, s1);
1410 Type st2 = types.memberType(t2, s2);
1411 if (types.overrideEquivalent(st1, st2)) {
1412 List<Type> tvars1 = st1.getTypeArguments();
1413 List<Type> tvars2 = st2.getTypeArguments();
1414 Type rt1 = st1.getReturnType();
1415 Type rt2 = types.subst(st2.getReturnType(), tvars2, tvars1);
1416 boolean compat =
1417 types.isSameType(rt1, rt2) ||
1418 rt1.tag >= CLASS && rt2.tag >= CLASS &&
1419 (types.covariantReturnType(rt1, rt2, Warner.noWarnings) ||
1420 types.covariantReturnType(rt2, rt1, Warner.noWarnings)) ||
1421 checkCommonOverriderIn(s1,s2,site);
1422 if (!compat) return s2;
1423 }
1424 }
1425 }
1426 return null;
1427 }
1428 //WHERE
1429 boolean checkCommonOverriderIn(Symbol s1, Symbol s2, Type site) {
1430 Map<TypeSymbol,Type> supertypes = new HashMap<TypeSymbol,Type>();
1431 Type st1 = types.memberType(site, s1);
1432 Type st2 = types.memberType(site, s2);
1433 closure(site, supertypes);
1434 for (Type t : supertypes.values()) {
1435 for (Scope.Entry e = t.tsym.members().lookup(s1.name); e.scope != null; e = e.next()) {
1436 Symbol s3 = e.sym;
1437 if (s3 == s1 || s3 == s2 || s3.kind != MTH || (s3.flags() & (BRIDGE|SYNTHETIC)) != 0) continue;
1438 Type st3 = types.memberType(site,s3);
1439 if (types.overrideEquivalent(st3, st1) && types.overrideEquivalent(st3, st2)) {
1440 if (s3.owner == site.tsym) {
1441 return true;
1442 }
1443 List<Type> tvars1 = st1.getTypeArguments();
1444 List<Type> tvars2 = st2.getTypeArguments();
1445 List<Type> tvars3 = st3.getTypeArguments();
1446 Type rt1 = st1.getReturnType();
1447 Type rt2 = st2.getReturnType();
1448 Type rt13 = types.subst(st3.getReturnType(), tvars3, tvars1);
1449 Type rt23 = types.subst(st3.getReturnType(), tvars3, tvars2);
1450 boolean compat =
1451 rt13.tag >= CLASS && rt23.tag >= CLASS &&
1452 (types.covariantReturnType(rt13, rt1, Warner.noWarnings) &&
1453 types.covariantReturnType(rt23, rt2, Warner.noWarnings));
1454 if (compat)
1455 return true;
1456 }
1457 }
1458 }
1459 return false;
1460 }
1462 /** Check that a given method conforms with any method it overrides.
1463 * @param tree The tree from which positions are extracted
1464 * for errors.
1465 * @param m The overriding method.
1466 */
1467 void checkOverride(JCTree tree, MethodSymbol m) {
1468 ClassSymbol origin = (ClassSymbol)m.owner;
1469 if ((origin.flags() & ENUM) != 0 && names.finalize.equals(m.name))
1470 if (m.overrides(syms.enumFinalFinalize, origin, types, false)) {
1471 log.error(tree.pos(), "enum.no.finalize");
1472 return;
1473 }
1474 for (Type t = types.supertype(origin.type); t.tag == CLASS;
1475 t = types.supertype(t)) {
1476 TypeSymbol c = t.tsym;
1477 Scope.Entry e = c.members().lookup(m.name);
1478 while (e.scope != null) {
1479 if (m.overrides(e.sym, origin, types, false))
1480 checkOverride(tree, m, (MethodSymbol)e.sym, origin);
1481 else if (e.sym.kind == MTH &&
1482 e.sym.isInheritedIn(origin, types) &&
1483 (e.sym.flags() & SYNTHETIC) == 0 &&
1484 !m.isConstructor()) {
1485 Type er1 = m.erasure(types);
1486 Type er2 = e.sym.erasure(types);
1487 if (types.isSameTypes(er1.getParameterTypes(),
1488 er2.getParameterTypes())) {
1489 log.error(TreeInfo.diagnosticPositionFor(m, tree),
1490 "name.clash.same.erasure.no.override",
1491 m, m.location(),
1492 e.sym, e.sym.location());
1493 }
1494 }
1495 e = e.next();
1496 }
1497 }
1498 }
1500 /** Check that all abstract members of given class have definitions.
1501 * @param pos Position to be used for error reporting.
1502 * @param c The class.
1503 */
1504 void checkAllDefined(DiagnosticPosition pos, ClassSymbol c) {
1505 try {
1506 MethodSymbol undef = firstUndef(c, c);
1507 if (undef != null) {
1508 if ((c.flags() & ENUM) != 0 &&
1509 types.supertype(c.type).tsym == syms.enumSym &&
1510 (c.flags() & FINAL) == 0) {
1511 // add the ABSTRACT flag to an enum
1512 c.flags_field |= ABSTRACT;
1513 } else {
1514 MethodSymbol undef1 =
1515 new MethodSymbol(undef.flags(), undef.name,
1516 types.memberType(c.type, undef), undef.owner);
1517 log.error(pos, "does.not.override.abstract",
1518 c, undef1, undef1.location());
1519 }
1520 }
1521 } catch (CompletionFailure ex) {
1522 completionError(pos, ex);
1523 }
1524 }
1525 //where
1526 /** Return first abstract member of class `c' that is not defined
1527 * in `impl', null if there is none.
1528 */
1529 private MethodSymbol firstUndef(ClassSymbol impl, ClassSymbol c) {
1530 MethodSymbol undef = null;
1531 // Do not bother to search in classes that are not abstract,
1532 // since they cannot have abstract members.
1533 if (c == impl || (c.flags() & (ABSTRACT | INTERFACE)) != 0) {
1534 Scope s = c.members();
1535 for (Scope.Entry e = s.elems;
1536 undef == null && e != null;
1537 e = e.sibling) {
1538 if (e.sym.kind == MTH &&
1539 (e.sym.flags() & (ABSTRACT|IPROXY)) == ABSTRACT) {
1540 MethodSymbol absmeth = (MethodSymbol)e.sym;
1541 MethodSymbol implmeth = absmeth.implementation(impl, types, true);
1542 if (implmeth == null || implmeth == absmeth)
1543 undef = absmeth;
1544 }
1545 }
1546 if (undef == null) {
1547 Type st = types.supertype(c.type);
1548 if (st.tag == CLASS)
1549 undef = firstUndef(impl, (ClassSymbol)st.tsym);
1550 }
1551 for (List<Type> l = types.interfaces(c.type);
1552 undef == null && l.nonEmpty();
1553 l = l.tail) {
1554 undef = firstUndef(impl, (ClassSymbol)l.head.tsym);
1555 }
1556 }
1557 return undef;
1558 }
1560 /** Check for cyclic references. Issue an error if the
1561 * symbol of the type referred to has a LOCKED flag set.
1562 *
1563 * @param pos Position to be used for error reporting.
1564 * @param t The type referred to.
1565 */
1566 void checkNonCyclic(DiagnosticPosition pos, Type t) {
1567 checkNonCyclicInternal(pos, t);
1568 }
1571 void checkNonCyclic(DiagnosticPosition pos, TypeVar t) {
1572 checkNonCyclic1(pos, t, List.<TypeVar>nil());
1573 }
1575 private void checkNonCyclic1(DiagnosticPosition pos, Type t, List<TypeVar> seen) {
1576 final TypeVar tv;
1577 if (t.tag == TYPEVAR && (t.tsym.flags() & UNATTRIBUTED) != 0)
1578 return;
1579 if (seen.contains(t)) {
1580 tv = (TypeVar)t;
1581 tv.bound = types.createErrorType(t);
1582 log.error(pos, "cyclic.inheritance", t);
1583 } else if (t.tag == TYPEVAR) {
1584 tv = (TypeVar)t;
1585 seen = seen.prepend(tv);
1586 for (Type b : types.getBounds(tv))
1587 checkNonCyclic1(pos, b, seen);
1588 }
1589 }
1591 /** Check for cyclic references. Issue an error if the
1592 * symbol of the type referred to has a LOCKED flag set.
1593 *
1594 * @param pos Position to be used for error reporting.
1595 * @param t The type referred to.
1596 * @returns True if the check completed on all attributed classes
1597 */
1598 private boolean checkNonCyclicInternal(DiagnosticPosition pos, Type t) {
1599 boolean complete = true; // was the check complete?
1600 //- System.err.println("checkNonCyclicInternal("+t+");");//DEBUG
1601 Symbol c = t.tsym;
1602 if ((c.flags_field & ACYCLIC) != 0) return true;
1604 if ((c.flags_field & LOCKED) != 0) {
1605 noteCyclic(pos, (ClassSymbol)c);
1606 } else if (!c.type.isErroneous()) {
1607 try {
1608 c.flags_field |= LOCKED;
1609 if (c.type.tag == CLASS) {
1610 ClassType clazz = (ClassType)c.type;
1611 if (clazz.interfaces_field != null)
1612 for (List<Type> l=clazz.interfaces_field; l.nonEmpty(); l=l.tail)
1613 complete &= checkNonCyclicInternal(pos, l.head);
1614 if (clazz.supertype_field != null) {
1615 Type st = clazz.supertype_field;
1616 if (st != null && st.tag == CLASS)
1617 complete &= checkNonCyclicInternal(pos, st);
1618 }
1619 if (c.owner.kind == TYP)
1620 complete &= checkNonCyclicInternal(pos, c.owner.type);
1621 }
1622 } finally {
1623 c.flags_field &= ~LOCKED;
1624 }
1625 }
1626 if (complete)
1627 complete = ((c.flags_field & UNATTRIBUTED) == 0) && c.completer == null;
1628 if (complete) c.flags_field |= ACYCLIC;
1629 return complete;
1630 }
1632 /** Note that we found an inheritance cycle. */
1633 private void noteCyclic(DiagnosticPosition pos, ClassSymbol c) {
1634 log.error(pos, "cyclic.inheritance", c);
1635 for (List<Type> l=types.interfaces(c.type); l.nonEmpty(); l=l.tail)
1636 l.head = types.createErrorType((ClassSymbol)l.head.tsym, Type.noType);
1637 Type st = types.supertype(c.type);
1638 if (st.tag == CLASS)
1639 ((ClassType)c.type).supertype_field = types.createErrorType((ClassSymbol)st.tsym, Type.noType);
1640 c.type = types.createErrorType(c, c.type);
1641 c.flags_field |= ACYCLIC;
1642 }
1644 /** Check that all methods which implement some
1645 * method conform to the method they implement.
1646 * @param tree The class definition whose members are checked.
1647 */
1648 void checkImplementations(JCClassDecl tree) {
1649 checkImplementations(tree, tree.sym);
1650 }
1651 //where
1652 /** Check that all methods which implement some
1653 * method in `ic' conform to the method they implement.
1654 */
1655 void checkImplementations(JCClassDecl tree, ClassSymbol ic) {
1656 ClassSymbol origin = tree.sym;
1657 for (List<Type> l = types.closure(ic.type); l.nonEmpty(); l = l.tail) {
1658 ClassSymbol lc = (ClassSymbol)l.head.tsym;
1659 if ((allowGenerics || origin != lc) && (lc.flags() & ABSTRACT) != 0) {
1660 for (Scope.Entry e=lc.members().elems; e != null; e=e.sibling) {
1661 if (e.sym.kind == MTH &&
1662 (e.sym.flags() & (STATIC|ABSTRACT)) == ABSTRACT) {
1663 MethodSymbol absmeth = (MethodSymbol)e.sym;
1664 MethodSymbol implmeth = absmeth.implementation(origin, types, false);
1665 if (implmeth != null && implmeth != absmeth &&
1666 (implmeth.owner.flags() & INTERFACE) ==
1667 (origin.flags() & INTERFACE)) {
1668 // don't check if implmeth is in a class, yet
1669 // origin is an interface. This case arises only
1670 // if implmeth is declared in Object. The reason is
1671 // that interfaces really don't inherit from
1672 // Object it's just that the compiler represents
1673 // things that way.
1674 checkOverride(tree, implmeth, absmeth, origin);
1675 }
1676 }
1677 }
1678 }
1679 }
1680 }
1682 /** Check that all abstract methods implemented by a class are
1683 * mutually compatible.
1684 * @param pos Position to be used for error reporting.
1685 * @param c The class whose interfaces are checked.
1686 */
1687 void checkCompatibleSupertypes(DiagnosticPosition pos, Type c) {
1688 List<Type> supertypes = types.interfaces(c);
1689 Type supertype = types.supertype(c);
1690 if (supertype.tag == CLASS &&
1691 (supertype.tsym.flags() & ABSTRACT) != 0)
1692 supertypes = supertypes.prepend(supertype);
1693 for (List<Type> l = supertypes; l.nonEmpty(); l = l.tail) {
1694 if (allowGenerics && !l.head.getTypeArguments().isEmpty() &&
1695 !checkCompatibleAbstracts(pos, l.head, l.head, c))
1696 return;
1697 for (List<Type> m = supertypes; m != l; m = m.tail)
1698 if (!checkCompatibleAbstracts(pos, l.head, m.head, c))
1699 return;
1700 }
1701 checkCompatibleConcretes(pos, c);
1702 }
1704 /** Check that class c does not implement directly or indirectly
1705 * the same parameterized interface with two different argument lists.
1706 * @param pos Position to be used for error reporting.
1707 * @param type The type whose interfaces are checked.
1708 */
1709 void checkClassBounds(DiagnosticPosition pos, Type type) {
1710 checkClassBounds(pos, new HashMap<TypeSymbol,Type>(), type);
1711 }
1712 //where
1713 /** Enter all interfaces of type `type' into the hash table `seensofar'
1714 * with their class symbol as key and their type as value. Make
1715 * sure no class is entered with two different types.
1716 */
1717 void checkClassBounds(DiagnosticPosition pos,
1718 Map<TypeSymbol,Type> seensofar,
1719 Type type) {
1720 if (type.isErroneous()) return;
1721 for (List<Type> l = types.interfaces(type); l.nonEmpty(); l = l.tail) {
1722 Type it = l.head;
1723 Type oldit = seensofar.put(it.tsym, it);
1724 if (oldit != null) {
1725 List<Type> oldparams = oldit.allparams();
1726 List<Type> newparams = it.allparams();
1727 if (!types.containsTypeEquivalent(oldparams, newparams))
1728 log.error(pos, "cant.inherit.diff.arg",
1729 it.tsym, Type.toString(oldparams),
1730 Type.toString(newparams));
1731 }
1732 checkClassBounds(pos, seensofar, it);
1733 }
1734 Type st = types.supertype(type);
1735 if (st != null) checkClassBounds(pos, seensofar, st);
1736 }
1738 /** Enter interface into into set.
1739 * If it existed already, issue a "repeated interface" error.
1740 */
1741 void checkNotRepeated(DiagnosticPosition pos, Type it, Set<Type> its) {
1742 if (its.contains(it))
1743 log.error(pos, "repeated.interface");
1744 else {
1745 its.add(it);
1746 }
1747 }
1749 /* *************************************************************************
1750 * Check annotations
1751 **************************************************************************/
1753 /** Annotation types are restricted to primitives, String, an
1754 * enum, an annotation, Class, Class<?>, Class<? extends
1755 * Anything>, arrays of the preceding.
1756 */
1757 void validateAnnotationType(JCTree restype) {
1758 // restype may be null if an error occurred, so don't bother validating it
1759 if (restype != null) {
1760 validateAnnotationType(restype.pos(), restype.type);
1761 }
1762 }
1764 void validateAnnotationType(DiagnosticPosition pos, Type type) {
1765 if (type.isPrimitive()) return;
1766 if (types.isSameType(type, syms.stringType)) return;
1767 if ((type.tsym.flags() & Flags.ENUM) != 0) return;
1768 if ((type.tsym.flags() & Flags.ANNOTATION) != 0) return;
1769 if (types.lowerBound(type).tsym == syms.classType.tsym) return;
1770 if (types.isArray(type) && !types.isArray(types.elemtype(type))) {
1771 validateAnnotationType(pos, types.elemtype(type));
1772 return;
1773 }
1774 log.error(pos, "invalid.annotation.member.type");
1775 }
1777 /**
1778 * "It is also a compile-time error if any method declared in an
1779 * annotation type has a signature that is override-equivalent to
1780 * that of any public or protected method declared in class Object
1781 * or in the interface annotation.Annotation."
1782 *
1783 * @jls3 9.6 Annotation Types
1784 */
1785 void validateAnnotationMethod(DiagnosticPosition pos, MethodSymbol m) {
1786 for (Type sup = syms.annotationType; sup.tag == CLASS; sup = types.supertype(sup)) {
1787 Scope s = sup.tsym.members();
1788 for (Scope.Entry e = s.lookup(m.name); e.scope != null; e = e.next()) {
1789 if (e.sym.kind == MTH &&
1790 (e.sym.flags() & (PUBLIC | PROTECTED)) != 0 &&
1791 types.overrideEquivalent(m.type, e.sym.type))
1792 log.error(pos, "intf.annotation.member.clash", e.sym, sup);
1793 }
1794 }
1795 }
1797 /** Check the annotations of a symbol.
1798 */
1799 public void validateAnnotations(List<JCAnnotation> annotations, Symbol s) {
1800 if (skipAnnotations) return;
1801 for (JCAnnotation a : annotations)
1802 validateAnnotation(a, s);
1803 }
1805 /** Check an annotation of a symbol.
1806 */
1807 public void validateAnnotation(JCAnnotation a, Symbol s) {
1808 validateAnnotation(a);
1810 if (!annotationApplicable(a, s))
1811 log.error(a.pos(), "annotation.type.not.applicable");
1813 if (a.annotationType.type.tsym == syms.overrideType.tsym) {
1814 if (!isOverrider(s))
1815 log.error(a.pos(), "method.does.not.override.superclass");
1816 }
1817 }
1819 /** Is s a method symbol that overrides a method in a superclass? */
1820 boolean isOverrider(Symbol s) {
1821 if (s.kind != MTH || s.isStatic())
1822 return false;
1823 MethodSymbol m = (MethodSymbol)s;
1824 TypeSymbol owner = (TypeSymbol)m.owner;
1825 for (Type sup : types.closure(owner.type)) {
1826 if (sup == owner.type)
1827 continue; // skip "this"
1828 Scope scope = sup.tsym.members();
1829 for (Scope.Entry e = scope.lookup(m.name); e.scope != null; e = e.next()) {
1830 if (!e.sym.isStatic() && m.overrides(e.sym, owner, types, true))
1831 return true;
1832 }
1833 }
1834 return false;
1835 }
1837 /** Is the annotation applicable to the symbol? */
1838 boolean annotationApplicable(JCAnnotation a, Symbol s) {
1839 Attribute.Compound atTarget =
1840 a.annotationType.type.tsym.attribute(syms.annotationTargetType.tsym);
1841 if (atTarget == null) return true;
1842 Attribute atValue = atTarget.member(names.value);
1843 if (!(atValue instanceof Attribute.Array)) return true; // error recovery
1844 Attribute.Array arr = (Attribute.Array) atValue;
1845 for (Attribute app : arr.values) {
1846 if (!(app instanceof Attribute.Enum)) return true; // recovery
1847 Attribute.Enum e = (Attribute.Enum) app;
1848 if (e.value.name == names.TYPE)
1849 { if (s.kind == TYP) return true; }
1850 else if (e.value.name == names.FIELD)
1851 { if (s.kind == VAR && s.owner.kind != MTH) return true; }
1852 else if (e.value.name == names.METHOD)
1853 { if (s.kind == MTH && !s.isConstructor()) return true; }
1854 else if (e.value.name == names.PARAMETER)
1855 { if (s.kind == VAR &&
1856 s.owner.kind == MTH &&
1857 (s.flags() & PARAMETER) != 0)
1858 return true;
1859 }
1860 else if (e.value.name == names.CONSTRUCTOR)
1861 { if (s.kind == MTH && s.isConstructor()) return true; }
1862 else if (e.value.name == names.LOCAL_VARIABLE)
1863 { if (s.kind == VAR && s.owner.kind == MTH &&
1864 (s.flags() & PARAMETER) == 0)
1865 return true;
1866 }
1867 else if (e.value.name == names.ANNOTATION_TYPE)
1868 { if (s.kind == TYP && (s.flags() & ANNOTATION) != 0)
1869 return true;
1870 }
1871 else if (e.value.name == names.PACKAGE)
1872 { if (s.kind == PCK) return true; }
1873 else
1874 return true; // recovery
1875 }
1876 return false;
1877 }
1879 /** Check an annotation value.
1880 */
1881 public void validateAnnotation(JCAnnotation a) {
1882 if (a.type.isErroneous()) return;
1884 // collect an inventory of the members
1885 Set<MethodSymbol> members = new HashSet<MethodSymbol>();
1886 for (Scope.Entry e = a.annotationType.type.tsym.members().elems;
1887 e != null;
1888 e = e.sibling)
1889 if (e.sym.kind == MTH)
1890 members.add((MethodSymbol) e.sym);
1892 // count them off as they're annotated
1893 for (JCTree arg : a.args) {
1894 if (arg.getTag() != JCTree.ASSIGN) continue; // recovery
1895 JCAssign assign = (JCAssign) arg;
1896 Symbol m = TreeInfo.symbol(assign.lhs);
1897 if (m == null || m.type.isErroneous()) continue;
1898 if (!members.remove(m))
1899 log.error(arg.pos(), "duplicate.annotation.member.value",
1900 m.name, a.type);
1901 if (assign.rhs.getTag() == ANNOTATION)
1902 validateAnnotation((JCAnnotation)assign.rhs);
1903 }
1905 // all the remaining ones better have default values
1906 for (MethodSymbol m : members)
1907 if (m.defaultValue == null && !m.type.isErroneous())
1908 log.error(a.pos(), "annotation.missing.default.value",
1909 a.type, m.name);
1911 // special case: java.lang.annotation.Target must not have
1912 // repeated values in its value member
1913 if (a.annotationType.type.tsym != syms.annotationTargetType.tsym ||
1914 a.args.tail == null)
1915 return;
1917 if (a.args.head.getTag() != JCTree.ASSIGN) return; // error recovery
1918 JCAssign assign = (JCAssign) a.args.head;
1919 Symbol m = TreeInfo.symbol(assign.lhs);
1920 if (m.name != names.value) return;
1921 JCTree rhs = assign.rhs;
1922 if (rhs.getTag() != JCTree.NEWARRAY) return;
1923 JCNewArray na = (JCNewArray) rhs;
1924 Set<Symbol> targets = new HashSet<Symbol>();
1925 for (JCTree elem : na.elems) {
1926 if (!targets.add(TreeInfo.symbol(elem))) {
1927 log.error(elem.pos(), "repeated.annotation.target");
1928 }
1929 }
1930 }
1932 void checkDeprecatedAnnotation(DiagnosticPosition pos, Symbol s) {
1933 if (allowAnnotations &&
1934 lint.isEnabled(Lint.LintCategory.DEP_ANN) &&
1935 (s.flags() & DEPRECATED) != 0 &&
1936 !syms.deprecatedType.isErroneous() &&
1937 s.attribute(syms.deprecatedType.tsym) == null) {
1938 log.warning(pos, "missing.deprecated.annotation");
1939 }
1940 }
1942 /* *************************************************************************
1943 * Check for recursive annotation elements.
1944 **************************************************************************/
1946 /** Check for cycles in the graph of annotation elements.
1947 */
1948 void checkNonCyclicElements(JCClassDecl tree) {
1949 if ((tree.sym.flags_field & ANNOTATION) == 0) return;
1950 assert (tree.sym.flags_field & LOCKED) == 0;
1951 try {
1952 tree.sym.flags_field |= LOCKED;
1953 for (JCTree def : tree.defs) {
1954 if (def.getTag() != JCTree.METHODDEF) continue;
1955 JCMethodDecl meth = (JCMethodDecl)def;
1956 checkAnnotationResType(meth.pos(), meth.restype.type);
1957 }
1958 } finally {
1959 tree.sym.flags_field &= ~LOCKED;
1960 tree.sym.flags_field |= ACYCLIC_ANN;
1961 }
1962 }
1964 void checkNonCyclicElementsInternal(DiagnosticPosition pos, TypeSymbol tsym) {
1965 if ((tsym.flags_field & ACYCLIC_ANN) != 0)
1966 return;
1967 if ((tsym.flags_field & LOCKED) != 0) {
1968 log.error(pos, "cyclic.annotation.element");
1969 return;
1970 }
1971 try {
1972 tsym.flags_field |= LOCKED;
1973 for (Scope.Entry e = tsym.members().elems; e != null; e = e.sibling) {
1974 Symbol s = e.sym;
1975 if (s.kind != Kinds.MTH)
1976 continue;
1977 checkAnnotationResType(pos, ((MethodSymbol)s).type.getReturnType());
1978 }
1979 } finally {
1980 tsym.flags_field &= ~LOCKED;
1981 tsym.flags_field |= ACYCLIC_ANN;
1982 }
1983 }
1985 void checkAnnotationResType(DiagnosticPosition pos, Type type) {
1986 switch (type.tag) {
1987 case TypeTags.CLASS:
1988 if ((type.tsym.flags() & ANNOTATION) != 0)
1989 checkNonCyclicElementsInternal(pos, type.tsym);
1990 break;
1991 case TypeTags.ARRAY:
1992 checkAnnotationResType(pos, types.elemtype(type));
1993 break;
1994 default:
1995 break; // int etc
1996 }
1997 }
1999 /* *************************************************************************
2000 * Check for cycles in the constructor call graph.
2001 **************************************************************************/
2003 /** Check for cycles in the graph of constructors calling other
2004 * constructors.
2005 */
2006 void checkCyclicConstructors(JCClassDecl tree) {
2007 Map<Symbol,Symbol> callMap = new HashMap<Symbol, Symbol>();
2009 // enter each constructor this-call into the map
2010 for (List<JCTree> l = tree.defs; l.nonEmpty(); l = l.tail) {
2011 JCMethodInvocation app = TreeInfo.firstConstructorCall(l.head);
2012 if (app == null) continue;
2013 JCMethodDecl meth = (JCMethodDecl) l.head;
2014 if (TreeInfo.name(app.meth) == names._this) {
2015 callMap.put(meth.sym, TreeInfo.symbol(app.meth));
2016 } else {
2017 meth.sym.flags_field |= ACYCLIC;
2018 }
2019 }
2021 // Check for cycles in the map
2022 Symbol[] ctors = new Symbol[0];
2023 ctors = callMap.keySet().toArray(ctors);
2024 for (Symbol caller : ctors) {
2025 checkCyclicConstructor(tree, caller, callMap);
2026 }
2027 }
2029 /** Look in the map to see if the given constructor is part of a
2030 * call cycle.
2031 */
2032 private void checkCyclicConstructor(JCClassDecl tree, Symbol ctor,
2033 Map<Symbol,Symbol> callMap) {
2034 if (ctor != null && (ctor.flags_field & ACYCLIC) == 0) {
2035 if ((ctor.flags_field & LOCKED) != 0) {
2036 log.error(TreeInfo.diagnosticPositionFor(ctor, tree),
2037 "recursive.ctor.invocation");
2038 } else {
2039 ctor.flags_field |= LOCKED;
2040 checkCyclicConstructor(tree, callMap.remove(ctor), callMap);
2041 ctor.flags_field &= ~LOCKED;
2042 }
2043 ctor.flags_field |= ACYCLIC;
2044 }
2045 }
2047 /* *************************************************************************
2048 * Miscellaneous
2049 **************************************************************************/
2051 /**
2052 * Return the opcode of the operator but emit an error if it is an
2053 * error.
2054 * @param pos position for error reporting.
2055 * @param operator an operator
2056 * @param tag a tree tag
2057 * @param left type of left hand side
2058 * @param right type of right hand side
2059 */
2060 int checkOperator(DiagnosticPosition pos,
2061 OperatorSymbol operator,
2062 int tag,
2063 Type left,
2064 Type right) {
2065 if (operator.opcode == ByteCodes.error) {
2066 log.error(pos,
2067 "operator.cant.be.applied",
2068 treeinfo.operatorName(tag),
2069 List.of(left, right));
2070 }
2071 return operator.opcode;
2072 }
2075 /**
2076 * Check for division by integer constant zero
2077 * @param pos Position for error reporting.
2078 * @param operator The operator for the expression
2079 * @param operand The right hand operand for the expression
2080 */
2081 void checkDivZero(DiagnosticPosition pos, Symbol operator, Type operand) {
2082 if (operand.constValue() != null
2083 && lint.isEnabled(Lint.LintCategory.DIVZERO)
2084 && operand.tag <= LONG
2085 && ((Number) (operand.constValue())).longValue() == 0) {
2086 int opc = ((OperatorSymbol)operator).opcode;
2087 if (opc == ByteCodes.idiv || opc == ByteCodes.imod
2088 || opc == ByteCodes.ldiv || opc == ByteCodes.lmod) {
2089 log.warning(pos, "div.zero");
2090 }
2091 }
2092 }
2094 /**
2095 * Check for empty statements after if
2096 */
2097 void checkEmptyIf(JCIf tree) {
2098 if (tree.thenpart.getTag() == JCTree.SKIP && tree.elsepart == null && lint.isEnabled(Lint.LintCategory.EMPTY))
2099 log.warning(tree.thenpart.pos(), "empty.if");
2100 }
2102 /** Check that symbol is unique in given scope.
2103 * @param pos Position for error reporting.
2104 * @param sym The symbol.
2105 * @param s The scope.
2106 */
2107 boolean checkUnique(DiagnosticPosition pos, Symbol sym, Scope s) {
2108 if (sym.type.isErroneous())
2109 return true;
2110 if (sym.owner.name == names.any) return false;
2111 for (Scope.Entry e = s.lookup(sym.name); e.scope == s; e = e.next()) {
2112 if (sym != e.sym &&
2113 sym.kind == e.sym.kind &&
2114 sym.name != names.error &&
2115 (sym.kind != MTH || types.hasSameArgs(types.erasure(sym.type), types.erasure(e.sym.type)))) {
2116 if ((sym.flags() & VARARGS) != (e.sym.flags() & VARARGS))
2117 varargsDuplicateError(pos, sym, e.sym);
2118 else if (sym.kind == MTH && !types.overrideEquivalent(sym.type, e.sym.type))
2119 duplicateErasureError(pos, sym, e.sym);
2120 else
2121 duplicateError(pos, e.sym);
2122 return false;
2123 }
2124 }
2125 return true;
2126 }
2127 //where
2128 /** Report duplicate declaration error.
2129 */
2130 void duplicateErasureError(DiagnosticPosition pos, Symbol sym1, Symbol sym2) {
2131 if (!sym1.type.isErroneous() && !sym2.type.isErroneous()) {
2132 log.error(pos, "name.clash.same.erasure", sym1, sym2);
2133 }
2134 }
2136 /** Check that single-type import is not already imported or top-level defined,
2137 * but make an exception for two single-type imports which denote the same type.
2138 * @param pos Position for error reporting.
2139 * @param sym The symbol.
2140 * @param s The scope
2141 */
2142 boolean checkUniqueImport(DiagnosticPosition pos, Symbol sym, Scope s) {
2143 return checkUniqueImport(pos, sym, s, false);
2144 }
2146 /** Check that static single-type import is not already imported or top-level defined,
2147 * but make an exception for two single-type imports which denote the same type.
2148 * @param pos Position for error reporting.
2149 * @param sym The symbol.
2150 * @param s The scope
2151 * @param staticImport Whether or not this was a static import
2152 */
2153 boolean checkUniqueStaticImport(DiagnosticPosition pos, Symbol sym, Scope s) {
2154 return checkUniqueImport(pos, sym, s, true);
2155 }
2157 /** Check that single-type import is not already imported or top-level defined,
2158 * but make an exception for two single-type imports which denote the same type.
2159 * @param pos Position for error reporting.
2160 * @param sym The symbol.
2161 * @param s The scope.
2162 * @param staticImport Whether or not this was a static import
2163 */
2164 private boolean checkUniqueImport(DiagnosticPosition pos, Symbol sym, Scope s, boolean staticImport) {
2165 for (Scope.Entry e = s.lookup(sym.name); e.scope != null; e = e.next()) {
2166 // is encountered class entered via a class declaration?
2167 boolean isClassDecl = e.scope == s;
2168 if ((isClassDecl || sym != e.sym) &&
2169 sym.kind == e.sym.kind &&
2170 sym.name != names.error) {
2171 if (!e.sym.type.isErroneous()) {
2172 String what = e.sym.toString();
2173 if (!isClassDecl) {
2174 if (staticImport)
2175 log.error(pos, "already.defined.static.single.import", what);
2176 else
2177 log.error(pos, "already.defined.single.import", what);
2178 }
2179 else if (sym != e.sym)
2180 log.error(pos, "already.defined.this.unit", what);
2181 }
2182 return false;
2183 }
2184 }
2185 return true;
2186 }
2188 /** Check that a qualified name is in canonical form (for import decls).
2189 */
2190 public void checkCanonical(JCTree tree) {
2191 if (!isCanonical(tree))
2192 log.error(tree.pos(), "import.requires.canonical",
2193 TreeInfo.symbol(tree));
2194 }
2195 // where
2196 private boolean isCanonical(JCTree tree) {
2197 while (tree.getTag() == JCTree.SELECT) {
2198 JCFieldAccess s = (JCFieldAccess) tree;
2199 if (s.sym.owner != TreeInfo.symbol(s.selected))
2200 return false;
2201 tree = s.selected;
2202 }
2203 return true;
2204 }
2206 private class ConversionWarner extends Warner {
2207 final String key;
2208 final Type found;
2209 final Type expected;
2210 public ConversionWarner(DiagnosticPosition pos, String key, Type found, Type expected) {
2211 super(pos);
2212 this.key = key;
2213 this.found = found;
2214 this.expected = expected;
2215 }
2217 public void warnUnchecked() {
2218 boolean warned = this.warned;
2219 super.warnUnchecked();
2220 if (warned) return; // suppress redundant diagnostics
2221 Object problem = diags.fragment(key);
2222 Check.this.warnUnchecked(pos(), "prob.found.req", problem, found, expected);
2223 }
2224 }
2226 public Warner castWarner(DiagnosticPosition pos, Type found, Type expected) {
2227 return new ConversionWarner(pos, "unchecked.cast.to.type", found, expected);
2228 }
2230 public Warner convertWarner(DiagnosticPosition pos, Type found, Type expected) {
2231 return new ConversionWarner(pos, "unchecked.assign", found, expected);
2232 }
2233 }