Mercurial > jdk8-mips64-public > langtools / file revision
src/share/classes/com/sun/tools/javac/comp/Check.java@f0e3ec1f9d9f
src/share/classes/com/sun/tools/javac/comp/Check.java
Sat, 01 May 2010 15:05:39 -0700
- author
- jrose
- date
- Sat, 01 May 2010 15:05:39 -0700
- changeset 571
- f0e3ec1f9d9f
- parent 537
- 9d9d08922405
- child 547
- 04cf82179fa7
- permissions
- -rw-r--r--
6939134: JSR 292 adjustments to method handle invocation
Summary: split MethodHandle.invoke into invokeExact and invokeGeneric
Reviewed-by: twisti
1 /*
2 * Copyright 1999-2009 Sun Microsystems, Inc. All Rights Reserved.
3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
4 *
5 * This code is free software; you can redistribute it and/or modify it
6 * under the terms of the GNU General Public License version 2 only, as
7 * published by the Free Software Foundation. Sun designates this
8 * particular file as subject to the "Classpath" exception as provided
9 * by Sun in the LICENSE file that accompanied this code.
10 *
11 * This code is distributed in the hope that it will be useful, but WITHOUT
12 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
13 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
14 * version 2 for more details (a copy is included in the LICENSE file that
15 * accompanied this code).
16 *
17 * You should have received a copy of the GNU General Public License version
18 * 2 along with this work; if not, write to the Free Software Foundation,
19 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
20 *
21 * Please contact Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,
22 * CA 95054 USA or visit www.sun.com if you need additional information or
23 * have any questions.
24 */
26 package com.sun.tools.javac.comp;
28 import java.util.*;
29 import java.util.Set;
31 import com.sun.tools.javac.code.*;
32 import com.sun.tools.javac.jvm.*;
33 import com.sun.tools.javac.tree.*;
34 import com.sun.tools.javac.util.*;
35 import com.sun.tools.javac.util.JCDiagnostic.DiagnosticPosition;
36 import com.sun.tools.javac.util.List;
38 import com.sun.tools.javac.tree.JCTree.*;
39 import com.sun.tools.javac.code.Lint;
40 import com.sun.tools.javac.code.Lint.LintCategory;
41 import com.sun.tools.javac.code.Type.*;
42 import com.sun.tools.javac.code.Symbol.*;
44 import static com.sun.tools.javac.code.Flags.*;
45 import static com.sun.tools.javac.code.Kinds.*;
46 import static com.sun.tools.javac.code.TypeTags.*;
48 /** Type checking helper class for the attribution phase.
49 *
50 * <p><b>This is NOT part of any API supported by Sun Microsystems. If
51 * you write code that depends on this, you do so at your own risk.
52 * This code and its internal interfaces are subject to change or
53 * deletion without notice.</b>
54 */
55 public class Check {
56 protected static final Context.Key<Check> checkKey =
57 new Context.Key<Check>();
59 private final Names names;
60 private final Log log;
61 private final Symtab syms;
62 private final Infer infer;
63 private final Types types;
64 private final JCDiagnostic.Factory diags;
65 private final boolean skipAnnotations;
66 private boolean warnOnSyntheticConflicts;
67 private final TreeInfo treeinfo;
69 // The set of lint options currently in effect. It is initialized
70 // from the context, and then is set/reset as needed by Attr as it
71 // visits all the various parts of the trees during attribution.
72 private Lint lint;
74 public static Check instance(Context context) {
75 Check instance = context.get(checkKey);
76 if (instance == null)
77 instance = new Check(context);
78 return instance;
79 }
81 protected Check(Context context) {
82 context.put(checkKey, this);
84 names = Names.instance(context);
85 log = Log.instance(context);
86 syms = Symtab.instance(context);
87 infer = Infer.instance(context);
88 this.types = Types.instance(context);
89 diags = JCDiagnostic.Factory.instance(context);
90 Options options = Options.instance(context);
91 lint = Lint.instance(context);
92 treeinfo = TreeInfo.instance(context);
94 Source source = Source.instance(context);
95 allowGenerics = source.allowGenerics();
96 allowAnnotations = source.allowAnnotations();
97 allowCovariantReturns = source.allowCovariantReturns();
98 complexInference = options.get("-complexinference") != null;
99 skipAnnotations = options.get("skipAnnotations") != null;
100 warnOnSyntheticConflicts = options.get("warnOnSyntheticConflicts") != null;
102 Target target = Target.instance(context);
103 syntheticNameChar = target.syntheticNameChar();
105 boolean verboseDeprecated = lint.isEnabled(LintCategory.DEPRECATION);
106 boolean verboseUnchecked = lint.isEnabled(LintCategory.UNCHECKED);
107 boolean verboseSunApi = lint.isEnabled(LintCategory.SUNAPI);
108 boolean enforceMandatoryWarnings = source.enforceMandatoryWarnings();
110 deprecationHandler = new MandatoryWarningHandler(log, verboseDeprecated,
111 enforceMandatoryWarnings, "deprecated");
112 uncheckedHandler = new MandatoryWarningHandler(log, verboseUnchecked,
113 enforceMandatoryWarnings, "unchecked");
114 sunApiHandler = new MandatoryWarningHandler(log, verboseSunApi,
115 enforceMandatoryWarnings, "sunapi");
116 }
118 /** Switch: generics enabled?
119 */
120 boolean allowGenerics;
122 /** Switch: annotations enabled?
123 */
124 boolean allowAnnotations;
126 /** Switch: covariant returns enabled?
127 */
128 boolean allowCovariantReturns;
130 /** Switch: -complexinference option set?
131 */
132 boolean complexInference;
134 /** Character for synthetic names
135 */
136 char syntheticNameChar;
138 /** A table mapping flat names of all compiled classes in this run to their
139 * symbols; maintained from outside.
140 */
141 public Map<Name,ClassSymbol> compiled = new HashMap<Name, ClassSymbol>();
143 /** A handler for messages about deprecated usage.
144 */
145 private MandatoryWarningHandler deprecationHandler;
147 /** A handler for messages about unchecked or unsafe usage.
148 */
149 private MandatoryWarningHandler uncheckedHandler;
151 /** A handler for messages about using Sun proprietary API.
152 */
153 private MandatoryWarningHandler sunApiHandler;
155 /* *************************************************************************
156 * Errors and Warnings
157 **************************************************************************/
159 Lint setLint(Lint newLint) {
160 Lint prev = lint;
161 lint = newLint;
162 return prev;
163 }
165 /** Warn about deprecated symbol.
166 * @param pos Position to be used for error reporting.
167 * @param sym The deprecated symbol.
168 */
169 void warnDeprecated(DiagnosticPosition pos, Symbol sym) {
170 if (!lint.isSuppressed(LintCategory.DEPRECATION))
171 deprecationHandler.report(pos, "has.been.deprecated", sym, sym.location());
172 }
174 /** Warn about unchecked operation.
175 * @param pos Position to be used for error reporting.
176 * @param msg A string describing the problem.
177 */
178 public void warnUnchecked(DiagnosticPosition pos, String msg, Object... args) {
179 if (!lint.isSuppressed(LintCategory.UNCHECKED))
180 uncheckedHandler.report(pos, msg, args);
181 }
183 /** Warn about using Sun proprietary API.
184 * @param pos Position to be used for error reporting.
185 * @param msg A string describing the problem.
186 */
187 public void warnSunApi(DiagnosticPosition pos, String msg, Object... args) {
188 if (!lint.isSuppressed(LintCategory.SUNAPI))
189 sunApiHandler.report(pos, msg, args);
190 }
192 public void warnStatic(DiagnosticPosition pos, String msg, Object... args) {
193 if (lint.isEnabled(LintCategory.STATIC))
194 log.warning(pos, msg, args);
195 }
197 /**
198 * Report any deferred diagnostics.
199 */
200 public void reportDeferredDiagnostics() {
201 deprecationHandler.reportDeferredDiagnostic();
202 uncheckedHandler.reportDeferredDiagnostic();
203 sunApiHandler.reportDeferredDiagnostic();
204 }
207 /** Report a failure to complete a class.
208 * @param pos Position to be used for error reporting.
209 * @param ex The failure to report.
210 */
211 public Type completionError(DiagnosticPosition pos, CompletionFailure ex) {
212 log.error(pos, "cant.access", ex.sym, ex.getDetailValue());
213 if (ex instanceof ClassReader.BadClassFile) throw new Abort();
214 else return syms.errType;
215 }
217 /** Report a type error.
218 * @param pos Position to be used for error reporting.
219 * @param problem A string describing the error.
220 * @param found The type that was found.
221 * @param req The type that was required.
222 */
223 Type typeError(DiagnosticPosition pos, Object problem, Type found, Type req) {
224 log.error(pos, "prob.found.req",
225 problem, found, req);
226 return types.createErrorType(found);
227 }
229 Type typeError(DiagnosticPosition pos, String problem, Type found, Type req, Object explanation) {
230 log.error(pos, "prob.found.req.1", problem, found, req, explanation);
231 return types.createErrorType(found);
232 }
234 /** Report an error that wrong type tag was found.
235 * @param pos Position to be used for error reporting.
236 * @param required An internationalized string describing the type tag
237 * required.
238 * @param found The type that was found.
239 */
240 Type typeTagError(DiagnosticPosition pos, Object required, Object found) {
241 // this error used to be raised by the parser,
242 // but has been delayed to this point:
243 if (found instanceof Type && ((Type)found).tag == VOID) {
244 log.error(pos, "illegal.start.of.type");
245 return syms.errType;
246 }
247 log.error(pos, "type.found.req", found, required);
248 return types.createErrorType(found instanceof Type ? (Type)found : syms.errType);
249 }
251 /** Report an error that symbol cannot be referenced before super
252 * has been called.
253 * @param pos Position to be used for error reporting.
254 * @param sym The referenced symbol.
255 */
256 void earlyRefError(DiagnosticPosition pos, Symbol sym) {
257 log.error(pos, "cant.ref.before.ctor.called", sym);
258 }
260 /** Report duplicate declaration error.
261 */
262 void duplicateError(DiagnosticPosition pos, Symbol sym) {
263 if (!sym.type.isErroneous()) {
264 log.error(pos, "already.defined", sym, sym.location());
265 }
266 }
268 /** Report array/varargs duplicate declaration
269 */
270 void varargsDuplicateError(DiagnosticPosition pos, Symbol sym1, Symbol sym2) {
271 if (!sym1.type.isErroneous() && !sym2.type.isErroneous()) {
272 log.error(pos, "array.and.varargs", sym1, sym2, sym2.location());
273 }
274 }
276 /* ************************************************************************
277 * duplicate declaration checking
278 *************************************************************************/
280 /** Check that variable does not hide variable with same name in
281 * immediately enclosing local scope.
282 * @param pos Position for error reporting.
283 * @param v The symbol.
284 * @param s The scope.
285 */
286 void checkTransparentVar(DiagnosticPosition pos, VarSymbol v, Scope s) {
287 if (s.next != null) {
288 for (Scope.Entry e = s.next.lookup(v.name);
289 e.scope != null && e.sym.owner == v.owner;
290 e = e.next()) {
291 if (e.sym.kind == VAR &&
292 (e.sym.owner.kind & (VAR | MTH)) != 0 &&
293 v.name != names.error) {
294 duplicateError(pos, e.sym);
295 return;
296 }
297 }
298 }
299 }
301 /** Check that a class or interface does not hide a class or
302 * interface with same name in immediately enclosing local scope.
303 * @param pos Position for error reporting.
304 * @param c The symbol.
305 * @param s The scope.
306 */
307 void checkTransparentClass(DiagnosticPosition pos, ClassSymbol c, Scope s) {
308 if (s.next != null) {
309 for (Scope.Entry e = s.next.lookup(c.name);
310 e.scope != null && e.sym.owner == c.owner;
311 e = e.next()) {
312 if (e.sym.kind == TYP &&
313 (e.sym.owner.kind & (VAR | MTH)) != 0 &&
314 c.name != names.error) {
315 duplicateError(pos, e.sym);
316 return;
317 }
318 }
319 }
320 }
322 /** Check that class does not have the same name as one of
323 * its enclosing classes, or as a class defined in its enclosing scope.
324 * return true if class is unique in its enclosing scope.
325 * @param pos Position for error reporting.
326 * @param name The class name.
327 * @param s The enclosing scope.
328 */
329 boolean checkUniqueClassName(DiagnosticPosition pos, Name name, Scope s) {
330 for (Scope.Entry e = s.lookup(name); e.scope == s; e = e.next()) {
331 if (e.sym.kind == TYP && e.sym.name != names.error) {
332 duplicateError(pos, e.sym);
333 return false;
334 }
335 }
336 for (Symbol sym = s.owner; sym != null; sym = sym.owner) {
337 if (sym.kind == TYP && sym.name == name && sym.name != names.error) {
338 duplicateError(pos, sym);
339 return true;
340 }
341 }
342 return true;
343 }
345 /* *************************************************************************
346 * Class name generation
347 **************************************************************************/
349 /** Return name of local class.
350 * This is of the form <enclClass> $ n <classname>
351 * where
352 * enclClass is the flat name of the enclosing class,
353 * classname is the simple name of the local class
354 */
355 Name localClassName(ClassSymbol c) {
356 for (int i=1; ; i++) {
357 Name flatname = names.
358 fromString("" + c.owner.enclClass().flatname +
359 syntheticNameChar + i +
360 c.name);
361 if (compiled.get(flatname) == null) return flatname;
362 }
363 }
365 /* *************************************************************************
366 * Type Checking
367 **************************************************************************/
369 /** Check that a given type is assignable to a given proto-type.
370 * If it is, return the type, otherwise return errType.
371 * @param pos Position to be used for error reporting.
372 * @param found The type that was found.
373 * @param req The type that was required.
374 */
375 Type checkType(DiagnosticPosition pos, Type found, Type req) {
376 if (req.tag == ERROR)
377 return req;
378 if (found.tag == FORALL)
379 return instantiatePoly(pos, (ForAll)found, req, convertWarner(pos, found, req));
380 if (req.tag == NONE)
381 return found;
382 if (types.isAssignable(found, req, convertWarner(pos, found, req)))
383 return found;
384 if (found.tag <= DOUBLE && req.tag <= DOUBLE)
385 return typeError(pos, diags.fragment("possible.loss.of.precision"), found, req);
386 if (found.isSuperBound()) {
387 log.error(pos, "assignment.from.super-bound", found);
388 return types.createErrorType(found);
389 }
390 if (req.isExtendsBound()) {
391 log.error(pos, "assignment.to.extends-bound", req);
392 return types.createErrorType(found);
393 }
394 return typeError(pos, diags.fragment("incompatible.types"), found, req);
395 }
397 /** Instantiate polymorphic type to some prototype, unless
398 * prototype is `anyPoly' in which case polymorphic type
399 * is returned unchanged.
400 */
401 Type instantiatePoly(DiagnosticPosition pos, ForAll t, Type pt, Warner warn) throws Infer.NoInstanceException {
402 if (pt == Infer.anyPoly && complexInference) {
403 return t;
404 } else if (pt == Infer.anyPoly || pt.tag == NONE) {
405 Type newpt = t.qtype.tag <= VOID ? t.qtype : syms.objectType;
406 return instantiatePoly(pos, t, newpt, warn);
407 } else if (pt.tag == ERROR) {
408 return pt;
409 } else {
410 try {
411 return infer.instantiateExpr(t, pt, warn);
412 } catch (Infer.NoInstanceException ex) {
413 if (ex.isAmbiguous) {
414 JCDiagnostic d = ex.getDiagnostic();
415 log.error(pos,
416 "undetermined.type" + (d!=null ? ".1" : ""),
417 t, d);
418 return types.createErrorType(pt);
419 } else {
420 JCDiagnostic d = ex.getDiagnostic();
421 return typeError(pos,
422 diags.fragment("incompatible.types" + (d!=null ? ".1" : ""), d),
423 t, pt);
424 }
425 } catch (Infer.InvalidInstanceException ex) {
426 JCDiagnostic d = ex.getDiagnostic();
427 log.error(pos, "invalid.inferred.types", t.tvars, d);
428 return types.createErrorType(pt);
429 }
430 }
431 }
433 /** Check that a given type can be cast to a given target type.
434 * Return the result of the cast.
435 * @param pos Position to be used for error reporting.
436 * @param found The type that is being cast.
437 * @param req The target type of the cast.
438 */
439 Type checkCastable(DiagnosticPosition pos, Type found, Type req) {
440 if (found.tag == FORALL) {
441 instantiatePoly(pos, (ForAll) found, req, castWarner(pos, found, req));
442 return req;
443 } else if (types.isCastable(found, req, castWarner(pos, found, req))) {
444 return req;
445 } else {
446 return typeError(pos,
447 diags.fragment("inconvertible.types"),
448 found, req);
449 }
450 }
451 //where
452 /** Is type a type variable, or a (possibly multi-dimensional) array of
453 * type variables?
454 */
455 boolean isTypeVar(Type t) {
456 return t.tag == TYPEVAR || t.tag == ARRAY && isTypeVar(types.elemtype(t));
457 }
459 /** Check that a type is within some bounds.
460 *
461 * Used in TypeApply to verify that, e.g., X in V<X> is a valid
462 * type argument.
463 * @param pos Position to be used for error reporting.
464 * @param a The type that should be bounded by bs.
465 * @param bs The bound.
466 */
467 private void checkExtends(DiagnosticPosition pos, Type a, TypeVar bs) {
468 if (a.isUnbound()) {
469 return;
470 } else if (a.tag != WILDCARD) {
471 a = types.upperBound(a);
472 for (List<Type> l = types.getBounds(bs); l.nonEmpty(); l = l.tail) {
473 if (!types.isSubtype(a, l.head)) {
474 log.error(pos, "not.within.bounds", a);
475 return;
476 }
477 }
478 } else if (a.isExtendsBound()) {
479 if (!types.isCastable(bs.getUpperBound(), types.upperBound(a), Warner.noWarnings))
480 log.error(pos, "not.within.bounds", a);
481 } else if (a.isSuperBound()) {
482 if (types.notSoftSubtype(types.lowerBound(a), bs.getUpperBound()))
483 log.error(pos, "not.within.bounds", a);
484 }
485 }
487 /** Check that a type is within some bounds.
488 *
489 * Used in TypeApply to verify that, e.g., X in V<X> is a valid
490 * type argument.
491 * @param pos Position to be used for error reporting.
492 * @param a The type that should be bounded by bs.
493 * @param bs The bound.
494 */
495 private void checkCapture(JCTypeApply tree) {
496 List<JCExpression> args = tree.getTypeArguments();
497 for (Type arg : types.capture(tree.type).getTypeArguments()) {
498 if (arg.tag == TYPEVAR && arg.getUpperBound().isErroneous()) {
499 log.error(args.head.pos, "not.within.bounds", args.head.type);
500 break;
501 }
502 args = args.tail;
503 }
504 }
506 /** Check that type is different from 'void'.
507 * @param pos Position to be used for error reporting.
508 * @param t The type to be checked.
509 */
510 Type checkNonVoid(DiagnosticPosition pos, Type t) {
511 if (t.tag == VOID) {
512 log.error(pos, "void.not.allowed.here");
513 return types.createErrorType(t);
514 } else {
515 return t;
516 }
517 }
519 /** Check that type is a class or interface type.
520 * @param pos Position to be used for error reporting.
521 * @param t The type to be checked.
522 */
523 Type checkClassType(DiagnosticPosition pos, Type t) {
524 if (t.tag != CLASS && t.tag != ERROR)
525 return typeTagError(pos,
526 diags.fragment("type.req.class"),
527 (t.tag == TYPEVAR)
528 ? diags.fragment("type.parameter", t)
529 : t);
530 else
531 return t;
532 }
534 /** Check that type is a class or interface type.
535 * @param pos Position to be used for error reporting.
536 * @param t The type to be checked.
537 * @param noBounds True if type bounds are illegal here.
538 */
539 Type checkClassType(DiagnosticPosition pos, Type t, boolean noBounds) {
540 t = checkClassType(pos, t);
541 if (noBounds && t.isParameterized()) {
542 List<Type> args = t.getTypeArguments();
543 while (args.nonEmpty()) {
544 if (args.head.tag == WILDCARD)
545 return typeTagError(pos,
546 Log.getLocalizedString("type.req.exact"),
547 args.head);
548 args = args.tail;
549 }
550 }
551 return t;
552 }
554 /** Check that type is a reifiable class, interface or array type.
555 * @param pos Position to be used for error reporting.
556 * @param t The type to be checked.
557 */
558 Type checkReifiableReferenceType(DiagnosticPosition pos, Type t) {
559 if (t.tag != CLASS && t.tag != ARRAY && t.tag != ERROR) {
560 return typeTagError(pos,
561 diags.fragment("type.req.class.array"),
562 t);
563 } else if (!types.isReifiable(t)) {
564 log.error(pos, "illegal.generic.type.for.instof");
565 return types.createErrorType(t);
566 } else {
567 return t;
568 }
569 }
571 /** Check that type is a reference type, i.e. a class, interface or array type
572 * or a type variable.
573 * @param pos Position to be used for error reporting.
574 * @param t The type to be checked.
575 */
576 Type checkRefType(DiagnosticPosition pos, Type t) {
577 switch (t.tag) {
578 case CLASS:
579 case ARRAY:
580 case TYPEVAR:
581 case WILDCARD:
582 case ERROR:
583 return t;
584 default:
585 return typeTagError(pos,
586 diags.fragment("type.req.ref"),
587 t);
588 }
589 }
591 /** Check that each type is a reference type, i.e. a class, interface or array type
592 * or a type variable.
593 * @param trees Original trees, used for error reporting.
594 * @param types The types to be checked.
595 */
596 List<Type> checkRefTypes(List<JCExpression> trees, List<Type> types) {
597 List<JCExpression> tl = trees;
598 for (List<Type> l = types; l.nonEmpty(); l = l.tail) {
599 l.head = checkRefType(tl.head.pos(), l.head);
600 tl = tl.tail;
601 }
602 return types;
603 }
605 /** Check that type is a null or reference type.
606 * @param pos Position to be used for error reporting.
607 * @param t The type to be checked.
608 */
609 Type checkNullOrRefType(DiagnosticPosition pos, Type t) {
610 switch (t.tag) {
611 case CLASS:
612 case ARRAY:
613 case TYPEVAR:
614 case WILDCARD:
615 case BOT:
616 case ERROR:
617 return t;
618 default:
619 return typeTagError(pos,
620 diags.fragment("type.req.ref"),
621 t);
622 }
623 }
625 /** Check that flag set does not contain elements of two conflicting sets. s
626 * Return true if it doesn't.
627 * @param pos Position to be used for error reporting.
628 * @param flags The set of flags to be checked.
629 * @param set1 Conflicting flags set #1.
630 * @param set2 Conflicting flags set #2.
631 */
632 boolean checkDisjoint(DiagnosticPosition pos, long flags, long set1, long set2) {
633 if ((flags & set1) != 0 && (flags & set2) != 0) {
634 log.error(pos,
635 "illegal.combination.of.modifiers",
636 asFlagSet(TreeInfo.firstFlag(flags & set1)),
637 asFlagSet(TreeInfo.firstFlag(flags & set2)));
638 return false;
639 } else
640 return true;
641 }
643 /** Check that the type inferred using the diamond operator does not contain
644 * non-denotable types such as captured types or intersection types.
645 * @param t the type inferred using the diamond operator
646 */
647 List<Type> checkDiamond(ClassType t) {
648 DiamondTypeChecker dtc = new DiamondTypeChecker();
649 ListBuffer<Type> buf = ListBuffer.lb();
650 for (Type arg : t.getTypeArguments()) {
651 if (!dtc.visit(arg, null)) {
652 buf.append(arg);
653 }
654 }
655 return buf.toList();
656 }
658 static class DiamondTypeChecker extends Types.SimpleVisitor<Boolean, Void> {
659 public Boolean visitType(Type t, Void s) {
660 return true;
661 }
662 @Override
663 public Boolean visitClassType(ClassType t, Void s) {
664 if (t.isCompound()) {
665 return false;
666 }
667 for (Type targ : t.getTypeArguments()) {
668 if (!visit(targ, s)) {
669 return false;
670 }
671 }
672 return true;
673 }
674 @Override
675 public Boolean visitCapturedType(CapturedType t, Void s) {
676 return false;
677 }
678 }
680 /** Check that given modifiers are legal for given symbol and
681 * return modifiers together with any implicit modififiers for that symbol.
682 * Warning: we can't use flags() here since this method
683 * is called during class enter, when flags() would cause a premature
684 * completion.
685 * @param pos Position to be used for error reporting.
686 * @param flags The set of modifiers given in a definition.
687 * @param sym The defined symbol.
688 */
689 long checkFlags(DiagnosticPosition pos, long flags, Symbol sym, JCTree tree) {
690 long mask;
691 long implicit = 0;
692 switch (sym.kind) {
693 case VAR:
694 if (sym.owner.kind != TYP)
695 mask = LocalVarFlags;
696 else if ((sym.owner.flags_field & INTERFACE) != 0)
697 mask = implicit = InterfaceVarFlags;
698 else
699 mask = VarFlags;
700 break;
701 case MTH:
702 if (sym.name == names.init) {
703 if ((sym.owner.flags_field & ENUM) != 0) {
704 // enum constructors cannot be declared public or
705 // protected and must be implicitly or explicitly
706 // private
707 implicit = PRIVATE;
708 mask = PRIVATE;
709 } else
710 mask = ConstructorFlags;
711 } else if ((sym.owner.flags_field & INTERFACE) != 0)
712 mask = implicit = InterfaceMethodFlags;
713 else {
714 mask = MethodFlags;
715 }
716 // Imply STRICTFP if owner has STRICTFP set.
717 if (((flags|implicit) & Flags.ABSTRACT) == 0)
718 implicit |= sym.owner.flags_field & STRICTFP;
719 break;
720 case TYP:
721 if (sym.isLocal()) {
722 mask = LocalClassFlags;
723 if (sym.name.isEmpty()) { // Anonymous class
724 // Anonymous classes in static methods are themselves static;
725 // that's why we admit STATIC here.
726 mask |= STATIC;
727 // JLS: Anonymous classes are final.
728 implicit |= FINAL;
729 }
730 if ((sym.owner.flags_field & STATIC) == 0 &&
731 (flags & ENUM) != 0)
732 log.error(pos, "enums.must.be.static");
733 } else if (sym.owner.kind == TYP) {
734 mask = MemberClassFlags;
735 if (sym.owner.owner.kind == PCK ||
736 (sym.owner.flags_field & STATIC) != 0)
737 mask |= STATIC;
738 else if ((flags & ENUM) != 0)
739 log.error(pos, "enums.must.be.static");
740 // Nested interfaces and enums are always STATIC (Spec ???)
741 if ((flags & (INTERFACE | ENUM)) != 0 ) implicit = STATIC;
742 } else {
743 mask = ClassFlags;
744 }
745 // Interfaces are always ABSTRACT
746 if ((flags & INTERFACE) != 0) implicit |= ABSTRACT;
748 if ((flags & ENUM) != 0) {
749 // enums can't be declared abstract or final
750 mask &= ~(ABSTRACT | FINAL);
751 implicit |= implicitEnumFinalFlag(tree);
752 }
753 // Imply STRICTFP if owner has STRICTFP set.
754 implicit |= sym.owner.flags_field & STRICTFP;
755 break;
756 default:
757 throw new AssertionError();
758 }
759 long illegal = flags & StandardFlags & ~mask;
760 if (illegal != 0) {
761 if ((illegal & INTERFACE) != 0) {
762 log.error(pos, "intf.not.allowed.here");
763 mask |= INTERFACE;
764 }
765 else {
766 log.error(pos,
767 "mod.not.allowed.here", asFlagSet(illegal));
768 }
769 }
770 else if ((sym.kind == TYP ||
771 // ISSUE: Disallowing abstract&private is no longer appropriate
772 // in the presence of inner classes. Should it be deleted here?
773 checkDisjoint(pos, flags,
774 ABSTRACT,
775 PRIVATE | STATIC))
776 &&
777 checkDisjoint(pos, flags,
778 ABSTRACT | INTERFACE,
779 FINAL | NATIVE | SYNCHRONIZED)
780 &&
781 checkDisjoint(pos, flags,
782 PUBLIC,
783 PRIVATE | PROTECTED)
784 &&
785 checkDisjoint(pos, flags,
786 PRIVATE,
787 PUBLIC | PROTECTED)
788 &&
789 checkDisjoint(pos, flags,
790 FINAL,
791 VOLATILE)
792 &&
793 (sym.kind == TYP ||
794 checkDisjoint(pos, flags,
795 ABSTRACT | NATIVE,
796 STRICTFP))) {
797 // skip
798 }
799 return flags & (mask | ~StandardFlags) | implicit;
800 }
803 /** Determine if this enum should be implicitly final.
804 *
805 * If the enum has no specialized enum contants, it is final.
806 *
807 * If the enum does have specialized enum contants, it is
808 * <i>not</i> final.
809 */
810 private long implicitEnumFinalFlag(JCTree tree) {
811 if (tree.getTag() != JCTree.CLASSDEF) return 0;
812 class SpecialTreeVisitor extends JCTree.Visitor {
813 boolean specialized;
814 SpecialTreeVisitor() {
815 this.specialized = false;
816 };
818 @Override
819 public void visitTree(JCTree tree) { /* no-op */ }
821 @Override
822 public void visitVarDef(JCVariableDecl tree) {
823 if ((tree.mods.flags & ENUM) != 0) {
824 if (tree.init instanceof JCNewClass &&
825 ((JCNewClass) tree.init).def != null) {
826 specialized = true;
827 }
828 }
829 }
830 }
832 SpecialTreeVisitor sts = new SpecialTreeVisitor();
833 JCClassDecl cdef = (JCClassDecl) tree;
834 for (JCTree defs: cdef.defs) {
835 defs.accept(sts);
836 if (sts.specialized) return 0;
837 }
838 return FINAL;
839 }
841 /* *************************************************************************
842 * Type Validation
843 **************************************************************************/
845 /** Validate a type expression. That is,
846 * check that all type arguments of a parametric type are within
847 * their bounds. This must be done in a second phase after type attributon
848 * since a class might have a subclass as type parameter bound. E.g:
849 *
850 * class B<A extends C> { ... }
851 * class C extends B<C> { ... }
852 *
853 * and we can't make sure that the bound is already attributed because
854 * of possible cycles.
855 */
856 private Validator validator = new Validator();
858 /** Visitor method: Validate a type expression, if it is not null, catching
859 * and reporting any completion failures.
860 */
861 void validate(JCTree tree, Env<AttrContext> env) {
862 try {
863 if (tree != null) {
864 validator.env = env;
865 tree.accept(validator);
866 checkRaw(tree, env);
867 }
868 } catch (CompletionFailure ex) {
869 completionError(tree.pos(), ex);
870 }
871 }
872 //where
873 void checkRaw(JCTree tree, Env<AttrContext> env) {
874 if (lint.isEnabled(Lint.LintCategory.RAW) &&
875 tree.type.tag == CLASS &&
876 !env.enclClass.name.isEmpty() && //anonymous or intersection
877 tree.type.isRaw()) {
878 log.warning(tree.pos(), "raw.class.use", tree.type, tree.type.tsym.type);
879 }
880 }
882 /** Visitor method: Validate a list of type expressions.
883 */
884 void validate(List<? extends JCTree> trees, Env<AttrContext> env) {
885 for (List<? extends JCTree> l = trees; l.nonEmpty(); l = l.tail)
886 validate(l.head, env);
887 }
889 /** A visitor class for type validation.
890 */
891 class Validator extends JCTree.Visitor {
893 @Override
894 public void visitTypeArray(JCArrayTypeTree tree) {
895 validate(tree.elemtype, env);
896 }
898 @Override
899 public void visitTypeApply(JCTypeApply tree) {
900 if (tree.type.tag == CLASS) {
901 List<Type> formals = tree.type.tsym.type.allparams();
902 List<Type> actuals = tree.type.allparams();
903 List<JCExpression> args = tree.arguments;
904 List<Type> forms = tree.type.tsym.type.getTypeArguments();
905 ListBuffer<TypeVar> tvars_buf = new ListBuffer<TypeVar>();
907 // For matching pairs of actual argument types `a' and
908 // formal type parameters with declared bound `b' ...
909 while (args.nonEmpty() && forms.nonEmpty()) {
910 validate(args.head, env);
912 // exact type arguments needs to know their
913 // bounds (for upper and lower bound
914 // calculations). So we create new TypeVars with
915 // bounds substed with actuals.
916 tvars_buf.append(types.substBound(((TypeVar)forms.head),
917 formals,
918 actuals));
920 args = args.tail;
921 forms = forms.tail;
922 }
924 args = tree.arguments;
925 List<Type> tvars_cap = types.substBounds(formals,
926 formals,
927 types.capture(tree.type).allparams());
928 while (args.nonEmpty() && tvars_cap.nonEmpty()) {
929 // Let the actual arguments know their bound
930 args.head.type.withTypeVar((TypeVar)tvars_cap.head);
931 args = args.tail;
932 tvars_cap = tvars_cap.tail;
933 }
935 args = tree.arguments;
936 List<TypeVar> tvars = tvars_buf.toList();
938 while (args.nonEmpty() && tvars.nonEmpty()) {
939 checkExtends(args.head.pos(),
940 args.head.type,
941 tvars.head);
942 args = args.tail;
943 tvars = tvars.tail;
944 }
946 checkCapture(tree);
948 // Check that this type is either fully parameterized, or
949 // not parameterized at all.
950 if (tree.type.getEnclosingType().isRaw())
951 log.error(tree.pos(), "improperly.formed.type.inner.raw.param");
952 if (tree.clazz.getTag() == JCTree.SELECT)
953 visitSelectInternal((JCFieldAccess)tree.clazz);
954 }
955 }
957 @Override
958 public void visitTypeParameter(JCTypeParameter tree) {
959 validate(tree.bounds, env);
960 checkClassBounds(tree.pos(), tree.type);
961 }
963 @Override
964 public void visitWildcard(JCWildcard tree) {
965 if (tree.inner != null)
966 validate(tree.inner, env);
967 }
969 @Override
970 public void visitSelect(JCFieldAccess tree) {
971 if (tree.type.tag == CLASS) {
972 visitSelectInternal(tree);
974 // Check that this type is either fully parameterized, or
975 // not parameterized at all.
976 if (tree.selected.type.isParameterized() && tree.type.tsym.type.getTypeArguments().nonEmpty())
977 log.error(tree.pos(), "improperly.formed.type.param.missing");
978 }
979 }
980 public void visitSelectInternal(JCFieldAccess tree) {
981 if (tree.type.tsym.isStatic() &&
982 tree.selected.type.isParameterized()) {
983 // The enclosing type is not a class, so we are
984 // looking at a static member type. However, the
985 // qualifying expression is parameterized.
986 log.error(tree.pos(), "cant.select.static.class.from.param.type");
987 } else {
988 // otherwise validate the rest of the expression
989 tree.selected.accept(this);
990 }
991 }
993 @Override
994 public void visitAnnotatedType(JCAnnotatedType tree) {
995 tree.underlyingType.accept(this);
996 }
998 /** Default visitor method: do nothing.
999 */
1000 @Override
1001 public void visitTree(JCTree tree) {
1002 }
1004 Env<AttrContext> env;
1005 }
1007 /* *************************************************************************
1008 * Exception checking
1009 **************************************************************************/
1011 /* The following methods treat classes as sets that contain
1012 * the class itself and all their subclasses
1013 */
1015 /** Is given type a subtype of some of the types in given list?
1016 */
1017 boolean subset(Type t, List<Type> ts) {
1018 for (List<Type> l = ts; l.nonEmpty(); l = l.tail)
1019 if (types.isSubtype(t, l.head)) return true;
1020 return false;
1021 }
1023 /** Is given type a subtype or supertype of
1024 * some of the types in given list?
1025 */
1026 boolean intersects(Type t, List<Type> ts) {
1027 for (List<Type> l = ts; l.nonEmpty(); l = l.tail)
1028 if (types.isSubtype(t, l.head) || types.isSubtype(l.head, t)) return true;
1029 return false;
1030 }
1032 /** Add type set to given type list, unless it is a subclass of some class
1033 * in the list.
1034 */
1035 List<Type> incl(Type t, List<Type> ts) {
1036 return subset(t, ts) ? ts : excl(t, ts).prepend(t);
1037 }
1039 /** Remove type set from type set list.
1040 */
1041 List<Type> excl(Type t, List<Type> ts) {
1042 if (ts.isEmpty()) {
1043 return ts;
1044 } else {
1045 List<Type> ts1 = excl(t, ts.tail);
1046 if (types.isSubtype(ts.head, t)) return ts1;
1047 else if (ts1 == ts.tail) return ts;
1048 else return ts1.prepend(ts.head);
1049 }
1050 }
1052 /** Form the union of two type set lists.
1053 */
1054 List<Type> union(List<Type> ts1, List<Type> ts2) {
1055 List<Type> ts = ts1;
1056 for (List<Type> l = ts2; l.nonEmpty(); l = l.tail)
1057 ts = incl(l.head, ts);
1058 return ts;
1059 }
1061 /** Form the difference of two type lists.
1062 */
1063 List<Type> diff(List<Type> ts1, List<Type> ts2) {
1064 List<Type> ts = ts1;
1065 for (List<Type> l = ts2; l.nonEmpty(); l = l.tail)
1066 ts = excl(l.head, ts);
1067 return ts;
1068 }
1070 /** Form the intersection of two type lists.
1071 */
1072 public List<Type> intersect(List<Type> ts1, List<Type> ts2) {
1073 List<Type> ts = List.nil();
1074 for (List<Type> l = ts1; l.nonEmpty(); l = l.tail)
1075 if (subset(l.head, ts2)) ts = incl(l.head, ts);
1076 for (List<Type> l = ts2; l.nonEmpty(); l = l.tail)
1077 if (subset(l.head, ts1)) ts = incl(l.head, ts);
1078 return ts;
1079 }
1081 /** Is exc an exception symbol that need not be declared?
1082 */
1083 boolean isUnchecked(ClassSymbol exc) {
1084 return
1085 exc.kind == ERR ||
1086 exc.isSubClass(syms.errorType.tsym, types) ||
1087 exc.isSubClass(syms.runtimeExceptionType.tsym, types);
1088 }
1090 /** Is exc an exception type that need not be declared?
1091 */
1092 boolean isUnchecked(Type exc) {
1093 return
1094 (exc.tag == TYPEVAR) ? isUnchecked(types.supertype(exc)) :
1095 (exc.tag == CLASS) ? isUnchecked((ClassSymbol)exc.tsym) :
1096 exc.tag == BOT;
1097 }
1099 /** Same, but handling completion failures.
1100 */
1101 boolean isUnchecked(DiagnosticPosition pos, Type exc) {
1102 try {
1103 return isUnchecked(exc);
1104 } catch (CompletionFailure ex) {
1105 completionError(pos, ex);
1106 return true;
1107 }
1108 }
1110 /** Is exc handled by given exception list?
1111 */
1112 boolean isHandled(Type exc, List<Type> handled) {
1113 return isUnchecked(exc) || subset(exc, handled);
1114 }
1116 /** Return all exceptions in thrown list that are not in handled list.
1117 * @param thrown The list of thrown exceptions.
1118 * @param handled The list of handled exceptions.
1119 */
1120 List<Type> unhandled(List<Type> thrown, List<Type> handled) {
1121 List<Type> unhandled = List.nil();
1122 for (List<Type> l = thrown; l.nonEmpty(); l = l.tail)
1123 if (!isHandled(l.head, handled)) unhandled = unhandled.prepend(l.head);
1124 return unhandled;
1125 }
1127 /* *************************************************************************
1128 * Overriding/Implementation checking
1129 **************************************************************************/
1131 /** The level of access protection given by a flag set,
1132 * where PRIVATE is highest and PUBLIC is lowest.
1133 */
1134 static int protection(long flags) {
1135 switch ((short)(flags & AccessFlags)) {
1136 case PRIVATE: return 3;
1137 case PROTECTED: return 1;
1138 default:
1139 case PUBLIC: return 0;
1140 case 0: return 2;
1141 }
1142 }
1144 /** A customized "cannot override" error message.
1145 * @param m The overriding method.
1146 * @param other The overridden method.
1147 * @return An internationalized string.
1148 */
1149 Object cannotOverride(MethodSymbol m, MethodSymbol other) {
1150 String key;
1151 if ((other.owner.flags() & INTERFACE) == 0)
1152 key = "cant.override";
1153 else if ((m.owner.flags() & INTERFACE) == 0)
1154 key = "cant.implement";
1155 else
1156 key = "clashes.with";
1157 return diags.fragment(key, m, m.location(), other, other.location());
1158 }
1160 /** A customized "override" warning message.
1161 * @param m The overriding method.
1162 * @param other The overridden method.
1163 * @return An internationalized string.
1164 */
1165 Object uncheckedOverrides(MethodSymbol m, MethodSymbol other) {
1166 String key;
1167 if ((other.owner.flags() & INTERFACE) == 0)
1168 key = "unchecked.override";
1169 else if ((m.owner.flags() & INTERFACE) == 0)
1170 key = "unchecked.implement";
1171 else
1172 key = "unchecked.clash.with";
1173 return diags.fragment(key, m, m.location(), other, other.location());
1174 }
1176 /** A customized "override" warning message.
1177 * @param m The overriding method.
1178 * @param other The overridden method.
1179 * @return An internationalized string.
1180 */
1181 Object varargsOverrides(MethodSymbol m, MethodSymbol other) {
1182 String key;
1183 if ((other.owner.flags() & INTERFACE) == 0)
1184 key = "varargs.override";
1185 else if ((m.owner.flags() & INTERFACE) == 0)
1186 key = "varargs.implement";
1187 else
1188 key = "varargs.clash.with";
1189 return diags.fragment(key, m, m.location(), other, other.location());
1190 }
1192 /** Check that this method conforms with overridden method 'other'.
1193 * where `origin' is the class where checking started.
1194 * Complications:
1195 * (1) Do not check overriding of synthetic methods
1196 * (reason: they might be final).
1197 * todo: check whether this is still necessary.
1198 * (2) Admit the case where an interface proxy throws fewer exceptions
1199 * than the method it implements. Augment the proxy methods with the
1200 * undeclared exceptions in this case.
1201 * (3) When generics are enabled, admit the case where an interface proxy
1202 * has a result type
1203 * extended by the result type of the method it implements.
1204 * Change the proxies result type to the smaller type in this case.
1205 *
1206 * @param tree The tree from which positions
1207 * are extracted for errors.
1208 * @param m The overriding method.
1209 * @param other The overridden method.
1210 * @param origin The class of which the overriding method
1211 * is a member.
1212 */
1213 void checkOverride(JCTree tree,
1214 MethodSymbol m,
1215 MethodSymbol other,
1216 ClassSymbol origin) {
1217 // Don't check overriding of synthetic methods or by bridge methods.
1218 if ((m.flags() & (SYNTHETIC|BRIDGE)) != 0 || (other.flags() & SYNTHETIC) != 0) {
1219 return;
1220 }
1222 // Error if static method overrides instance method (JLS 8.4.6.2).
1223 if ((m.flags() & STATIC) != 0 &&
1224 (other.flags() & STATIC) == 0) {
1225 log.error(TreeInfo.diagnosticPositionFor(m, tree), "override.static",
1226 cannotOverride(m, other));
1227 return;
1228 }
1230 // Error if instance method overrides static or final
1231 // method (JLS 8.4.6.1).
1232 if ((other.flags() & FINAL) != 0 ||
1233 (m.flags() & STATIC) == 0 &&
1234 (other.flags() & STATIC) != 0) {
1235 log.error(TreeInfo.diagnosticPositionFor(m, tree), "override.meth",
1236 cannotOverride(m, other),
1237 asFlagSet(other.flags() & (FINAL | STATIC)));
1238 return;
1239 }
1241 if ((m.owner.flags() & ANNOTATION) != 0) {
1242 // handled in validateAnnotationMethod
1243 return;
1244 }
1246 // Error if overriding method has weaker access (JLS 8.4.6.3).
1247 if ((origin.flags() & INTERFACE) == 0 &&
1248 protection(m.flags()) > protection(other.flags())) {
1249 log.error(TreeInfo.diagnosticPositionFor(m, tree), "override.weaker.access",
1250 cannotOverride(m, other),
1251 other.flags() == 0 ?
1252 Flag.PACKAGE :
1253 asFlagSet(other.flags() & AccessFlags));
1254 return;
1255 }
1257 Type mt = types.memberType(origin.type, m);
1258 Type ot = types.memberType(origin.type, other);
1259 // Error if overriding result type is different
1260 // (or, in the case of generics mode, not a subtype) of
1261 // overridden result type. We have to rename any type parameters
1262 // before comparing types.
1263 List<Type> mtvars = mt.getTypeArguments();
1264 List<Type> otvars = ot.getTypeArguments();
1265 Type mtres = mt.getReturnType();
1266 Type otres = types.subst(ot.getReturnType(), otvars, mtvars);
1268 overrideWarner.warned = false;
1269 boolean resultTypesOK =
1270 types.returnTypeSubstitutable(mt, ot, otres, overrideWarner);
1271 if (!resultTypesOK) {
1272 if (!allowCovariantReturns &&
1273 m.owner != origin &&
1274 m.owner.isSubClass(other.owner, types)) {
1275 // allow limited interoperability with covariant returns
1276 } else {
1277 log.error(TreeInfo.diagnosticPositionFor(m, tree),
1278 "override.incompatible.ret",
1279 cannotOverride(m, other),
1280 mtres, otres);
1281 return;
1282 }
1283 } else if (overrideWarner.warned) {
1284 warnUnchecked(TreeInfo.diagnosticPositionFor(m, tree),
1285 "override.unchecked.ret",
1286 uncheckedOverrides(m, other),
1287 mtres, otres);
1288 }
1290 // Error if overriding method throws an exception not reported
1291 // by overridden method.
1292 List<Type> otthrown = types.subst(ot.getThrownTypes(), otvars, mtvars);
1293 List<Type> unhandledErased = unhandled(mt.getThrownTypes(), types.erasure(otthrown));
1294 List<Type> unhandledUnerased = unhandled(mt.getThrownTypes(), otthrown);
1295 if (unhandledErased.nonEmpty()) {
1296 log.error(TreeInfo.diagnosticPositionFor(m, tree),
1297 "override.meth.doesnt.throw",
1298 cannotOverride(m, other),
1299 unhandledUnerased.head);
1300 return;
1301 }
1302 else if (unhandledUnerased.nonEmpty()) {
1303 warnUnchecked(TreeInfo.diagnosticPositionFor(m, tree),
1304 "override.unchecked.thrown",
1305 cannotOverride(m, other),
1306 unhandledUnerased.head);
1307 return;
1308 }
1310 // Optional warning if varargs don't agree
1311 if ((((m.flags() ^ other.flags()) & Flags.VARARGS) != 0)
1312 && lint.isEnabled(Lint.LintCategory.OVERRIDES)) {
1313 log.warning(TreeInfo.diagnosticPositionFor(m, tree),
1314 ((m.flags() & Flags.VARARGS) != 0)
1315 ? "override.varargs.missing"
1316 : "override.varargs.extra",
1317 varargsOverrides(m, other));
1318 }
1320 // Warn if instance method overrides bridge method (compiler spec ??)
1321 if ((other.flags() & BRIDGE) != 0) {
1322 log.warning(TreeInfo.diagnosticPositionFor(m, tree), "override.bridge",
1323 uncheckedOverrides(m, other));
1324 }
1326 // Warn if a deprecated method overridden by a non-deprecated one.
1327 if ((other.flags() & DEPRECATED) != 0
1328 && (m.flags() & DEPRECATED) == 0
1329 && m.outermostClass() != other.outermostClass()
1330 && !isDeprecatedOverrideIgnorable(other, origin)) {
1331 warnDeprecated(TreeInfo.diagnosticPositionFor(m, tree), other);
1332 }
1333 }
1334 // where
1335 private boolean isDeprecatedOverrideIgnorable(MethodSymbol m, ClassSymbol origin) {
1336 // If the method, m, is defined in an interface, then ignore the issue if the method
1337 // is only inherited via a supertype and also implemented in the supertype,
1338 // because in that case, we will rediscover the issue when examining the method
1339 // in the supertype.
1340 // If the method, m, is not defined in an interface, then the only time we need to
1341 // address the issue is when the method is the supertype implemementation: any other
1342 // case, we will have dealt with when examining the supertype classes
1343 ClassSymbol mc = m.enclClass();
1344 Type st = types.supertype(origin.type);
1345 if (st.tag != CLASS)
1346 return true;
1347 MethodSymbol stimpl = m.implementation((ClassSymbol)st.tsym, types, false);
1349 if (mc != null && ((mc.flags() & INTERFACE) != 0)) {
1350 List<Type> intfs = types.interfaces(origin.type);
1351 return (intfs.contains(mc.type) ? false : (stimpl != null));
1352 }
1353 else
1354 return (stimpl != m);
1355 }
1358 // used to check if there were any unchecked conversions
1359 Warner overrideWarner = new Warner();
1361 /** Check that a class does not inherit two concrete methods
1362 * with the same signature.
1363 * @param pos Position to be used for error reporting.
1364 * @param site The class type to be checked.
1365 */
1366 public void checkCompatibleConcretes(DiagnosticPosition pos, Type site) {
1367 Type sup = types.supertype(site);
1368 if (sup.tag != CLASS) return;
1370 for (Type t1 = sup;
1371 t1.tsym.type.isParameterized();
1372 t1 = types.supertype(t1)) {
1373 for (Scope.Entry e1 = t1.tsym.members().elems;
1374 e1 != null;
1375 e1 = e1.sibling) {
1376 Symbol s1 = e1.sym;
1377 if (s1.kind != MTH ||
1378 (s1.flags() & (STATIC|SYNTHETIC|BRIDGE)) != 0 ||
1379 !s1.isInheritedIn(site.tsym, types) ||
1380 ((MethodSymbol)s1).implementation(site.tsym,
1381 types,
1382 true) != s1)
1383 continue;
1384 Type st1 = types.memberType(t1, s1);
1385 int s1ArgsLength = st1.getParameterTypes().length();
1386 if (st1 == s1.type) continue;
1388 for (Type t2 = sup;
1389 t2.tag == CLASS;
1390 t2 = types.supertype(t2)) {
1391 for (Scope.Entry e2 = t2.tsym.members().lookup(s1.name);
1392 e2.scope != null;
1393 e2 = e2.next()) {
1394 Symbol s2 = e2.sym;
1395 if (s2 == s1 ||
1396 s2.kind != MTH ||
1397 (s2.flags() & (STATIC|SYNTHETIC|BRIDGE)) != 0 ||
1398 s2.type.getParameterTypes().length() != s1ArgsLength ||
1399 !s2.isInheritedIn(site.tsym, types) ||
1400 ((MethodSymbol)s2).implementation(site.tsym,
1401 types,
1402 true) != s2)
1403 continue;
1404 Type st2 = types.memberType(t2, s2);
1405 if (types.overrideEquivalent(st1, st2))
1406 log.error(pos, "concrete.inheritance.conflict",
1407 s1, t1, s2, t2, sup);
1408 }
1409 }
1410 }
1411 }
1412 }
1414 /** Check that classes (or interfaces) do not each define an abstract
1415 * method with same name and arguments but incompatible return types.
1416 * @param pos Position to be used for error reporting.
1417 * @param t1 The first argument type.
1418 * @param t2 The second argument type.
1419 */
1420 public boolean checkCompatibleAbstracts(DiagnosticPosition pos,
1421 Type t1,
1422 Type t2) {
1423 return checkCompatibleAbstracts(pos, t1, t2,
1424 types.makeCompoundType(t1, t2));
1425 }
1427 public boolean checkCompatibleAbstracts(DiagnosticPosition pos,
1428 Type t1,
1429 Type t2,
1430 Type site) {
1431 Symbol sym = firstIncompatibility(t1, t2, site);
1432 if (sym != null) {
1433 log.error(pos, "types.incompatible.diff.ret",
1434 t1, t2, sym.name +
1435 "(" + types.memberType(t2, sym).getParameterTypes() + ")");
1436 return false;
1437 }
1438 return true;
1439 }
1441 /** Return the first method which is defined with same args
1442 * but different return types in two given interfaces, or null if none
1443 * exists.
1444 * @param t1 The first type.
1445 * @param t2 The second type.
1446 * @param site The most derived type.
1447 * @returns symbol from t2 that conflicts with one in t1.
1448 */
1449 private Symbol firstIncompatibility(Type t1, Type t2, Type site) {
1450 Map<TypeSymbol,Type> interfaces1 = new HashMap<TypeSymbol,Type>();
1451 closure(t1, interfaces1);
1452 Map<TypeSymbol,Type> interfaces2;
1453 if (t1 == t2)
1454 interfaces2 = interfaces1;
1455 else
1456 closure(t2, interfaces1, interfaces2 = new HashMap<TypeSymbol,Type>());
1458 for (Type t3 : interfaces1.values()) {
1459 for (Type t4 : interfaces2.values()) {
1460 Symbol s = firstDirectIncompatibility(t3, t4, site);
1461 if (s != null) return s;
1462 }
1463 }
1464 return null;
1465 }
1467 /** Compute all the supertypes of t, indexed by type symbol. */
1468 private void closure(Type t, Map<TypeSymbol,Type> typeMap) {
1469 if (t.tag != CLASS) return;
1470 if (typeMap.put(t.tsym, t) == null) {
1471 closure(types.supertype(t), typeMap);
1472 for (Type i : types.interfaces(t))
1473 closure(i, typeMap);
1474 }
1475 }
1477 /** Compute all the supertypes of t, indexed by type symbol (except thise in typesSkip). */
1478 private void closure(Type t, Map<TypeSymbol,Type> typesSkip, Map<TypeSymbol,Type> typeMap) {
1479 if (t.tag != CLASS) return;
1480 if (typesSkip.get(t.tsym) != null) return;
1481 if (typeMap.put(t.tsym, t) == null) {
1482 closure(types.supertype(t), typesSkip, typeMap);
1483 for (Type i : types.interfaces(t))
1484 closure(i, typesSkip, typeMap);
1485 }
1486 }
1488 /** Return the first method in t2 that conflicts with a method from t1. */
1489 private Symbol firstDirectIncompatibility(Type t1, Type t2, Type site) {
1490 for (Scope.Entry e1 = t1.tsym.members().elems; e1 != null; e1 = e1.sibling) {
1491 Symbol s1 = e1.sym;
1492 Type st1 = null;
1493 if (s1.kind != MTH || !s1.isInheritedIn(site.tsym, types)) continue;
1494 Symbol impl = ((MethodSymbol)s1).implementation(site.tsym, types, false);
1495 if (impl != null && (impl.flags() & ABSTRACT) == 0) continue;
1496 for (Scope.Entry e2 = t2.tsym.members().lookup(s1.name); e2.scope != null; e2 = e2.next()) {
1497 Symbol s2 = e2.sym;
1498 if (s1 == s2) continue;
1499 if (s2.kind != MTH || !s2.isInheritedIn(site.tsym, types)) continue;
1500 if (st1 == null) st1 = types.memberType(t1, s1);
1501 Type st2 = types.memberType(t2, s2);
1502 if (types.overrideEquivalent(st1, st2)) {
1503 List<Type> tvars1 = st1.getTypeArguments();
1504 List<Type> tvars2 = st2.getTypeArguments();
1505 Type rt1 = st1.getReturnType();
1506 Type rt2 = types.subst(st2.getReturnType(), tvars2, tvars1);
1507 boolean compat =
1508 types.isSameType(rt1, rt2) ||
1509 rt1.tag >= CLASS && rt2.tag >= CLASS &&
1510 (types.covariantReturnType(rt1, rt2, Warner.noWarnings) ||
1511 types.covariantReturnType(rt2, rt1, Warner.noWarnings)) ||
1512 checkCommonOverriderIn(s1,s2,site);
1513 if (!compat) return s2;
1514 }
1515 }
1516 }
1517 return null;
1518 }
1519 //WHERE
1520 boolean checkCommonOverriderIn(Symbol s1, Symbol s2, Type site) {
1521 Map<TypeSymbol,Type> supertypes = new HashMap<TypeSymbol,Type>();
1522 Type st1 = types.memberType(site, s1);
1523 Type st2 = types.memberType(site, s2);
1524 closure(site, supertypes);
1525 for (Type t : supertypes.values()) {
1526 for (Scope.Entry e = t.tsym.members().lookup(s1.name); e.scope != null; e = e.next()) {
1527 Symbol s3 = e.sym;
1528 if (s3 == s1 || s3 == s2 || s3.kind != MTH || (s3.flags() & (BRIDGE|SYNTHETIC)) != 0) continue;
1529 Type st3 = types.memberType(site,s3);
1530 if (types.overrideEquivalent(st3, st1) && types.overrideEquivalent(st3, st2)) {
1531 if (s3.owner == site.tsym) {
1532 return true;
1533 }
1534 List<Type> tvars1 = st1.getTypeArguments();
1535 List<Type> tvars2 = st2.getTypeArguments();
1536 List<Type> tvars3 = st3.getTypeArguments();
1537 Type rt1 = st1.getReturnType();
1538 Type rt2 = st2.getReturnType();
1539 Type rt13 = types.subst(st3.getReturnType(), tvars3, tvars1);
1540 Type rt23 = types.subst(st3.getReturnType(), tvars3, tvars2);
1541 boolean compat =
1542 rt13.tag >= CLASS && rt23.tag >= CLASS &&
1543 (types.covariantReturnType(rt13, rt1, Warner.noWarnings) &&
1544 types.covariantReturnType(rt23, rt2, Warner.noWarnings));
1545 if (compat)
1546 return true;
1547 }
1548 }
1549 }
1550 return false;
1551 }
1553 /** Check that a given method conforms with any method it overrides.
1554 * @param tree The tree from which positions are extracted
1555 * for errors.
1556 * @param m The overriding method.
1557 */
1558 void checkOverride(JCTree tree, MethodSymbol m) {
1559 ClassSymbol origin = (ClassSymbol)m.owner;
1560 if ((origin.flags() & ENUM) != 0 && names.finalize.equals(m.name))
1561 if (m.overrides(syms.enumFinalFinalize, origin, types, false)) {
1562 log.error(tree.pos(), "enum.no.finalize");
1563 return;
1564 }
1565 for (Type t = types.supertype(origin.type); t.tag == CLASS;
1566 t = types.supertype(t)) {
1567 TypeSymbol c = t.tsym;
1568 Scope.Entry e = c.members().lookup(m.name);
1569 while (e.scope != null) {
1570 if (m.overrides(e.sym, origin, types, false))
1571 checkOverride(tree, m, (MethodSymbol)e.sym, origin);
1572 else if (e.sym.kind == MTH &&
1573 e.sym.isInheritedIn(origin, types) &&
1574 (e.sym.flags() & SYNTHETIC) == 0 &&
1575 !m.isConstructor()) {
1576 Type er1 = m.erasure(types);
1577 Type er2 = e.sym.erasure(types);
1578 if (types.isSameTypes(er1.getParameterTypes(),
1579 er2.getParameterTypes())) {
1580 log.error(TreeInfo.diagnosticPositionFor(m, tree),
1581 "name.clash.same.erasure.no.override",
1582 m, m.location(),
1583 e.sym, e.sym.location());
1584 }
1585 }
1586 e = e.next();
1587 }
1588 }
1589 }
1591 /** Check that all abstract members of given class have definitions.
1592 * @param pos Position to be used for error reporting.
1593 * @param c The class.
1594 */
1595 void checkAllDefined(DiagnosticPosition pos, ClassSymbol c) {
1596 try {
1597 MethodSymbol undef = firstUndef(c, c);
1598 if (undef != null) {
1599 if ((c.flags() & ENUM) != 0 &&
1600 types.supertype(c.type).tsym == syms.enumSym &&
1601 (c.flags() & FINAL) == 0) {
1602 // add the ABSTRACT flag to an enum
1603 c.flags_field |= ABSTRACT;
1604 } else {
1605 MethodSymbol undef1 =
1606 new MethodSymbol(undef.flags(), undef.name,
1607 types.memberType(c.type, undef), undef.owner);
1608 log.error(pos, "does.not.override.abstract",
1609 c, undef1, undef1.location());
1610 }
1611 }
1612 } catch (CompletionFailure ex) {
1613 completionError(pos, ex);
1614 }
1615 }
1616 //where
1617 /** Return first abstract member of class `c' that is not defined
1618 * in `impl', null if there is none.
1619 */
1620 private MethodSymbol firstUndef(ClassSymbol impl, ClassSymbol c) {
1621 MethodSymbol undef = null;
1622 // Do not bother to search in classes that are not abstract,
1623 // since they cannot have abstract members.
1624 if (c == impl || (c.flags() & (ABSTRACT | INTERFACE)) != 0) {
1625 Scope s = c.members();
1626 for (Scope.Entry e = s.elems;
1627 undef == null && e != null;
1628 e = e.sibling) {
1629 if (e.sym.kind == MTH &&
1630 (e.sym.flags() & (ABSTRACT|IPROXY)) == ABSTRACT) {
1631 MethodSymbol absmeth = (MethodSymbol)e.sym;
1632 MethodSymbol implmeth = absmeth.implementation(impl, types, true);
1633 if (implmeth == null || implmeth == absmeth)
1634 undef = absmeth;
1635 }
1636 }
1637 if (undef == null) {
1638 Type st = types.supertype(c.type);
1639 if (st.tag == CLASS)
1640 undef = firstUndef(impl, (ClassSymbol)st.tsym);
1641 }
1642 for (List<Type> l = types.interfaces(c.type);
1643 undef == null && l.nonEmpty();
1644 l = l.tail) {
1645 undef = firstUndef(impl, (ClassSymbol)l.head.tsym);
1646 }
1647 }
1648 return undef;
1649 }
1651 /** Check for cyclic references. Issue an error if the
1652 * symbol of the type referred to has a LOCKED flag set.
1653 *
1654 * @param pos Position to be used for error reporting.
1655 * @param t The type referred to.
1656 */
1657 void checkNonCyclic(DiagnosticPosition pos, Type t) {
1658 checkNonCyclicInternal(pos, t);
1659 }
1662 void checkNonCyclic(DiagnosticPosition pos, TypeVar t) {
1663 checkNonCyclic1(pos, t, List.<TypeVar>nil());
1664 }
1666 private void checkNonCyclic1(DiagnosticPosition pos, Type t, List<TypeVar> seen) {
1667 final TypeVar tv;
1668 if (t.tag == TYPEVAR && (t.tsym.flags() & UNATTRIBUTED) != 0)
1669 return;
1670 if (seen.contains(t)) {
1671 tv = (TypeVar)t;
1672 tv.bound = types.createErrorType(t);
1673 log.error(pos, "cyclic.inheritance", t);
1674 } else if (t.tag == TYPEVAR) {
1675 tv = (TypeVar)t;
1676 seen = seen.prepend(tv);
1677 for (Type b : types.getBounds(tv))
1678 checkNonCyclic1(pos, b, seen);
1679 }
1680 }
1682 /** Check for cyclic references. Issue an error if the
1683 * symbol of the type referred to has a LOCKED flag set.
1684 *
1685 * @param pos Position to be used for error reporting.
1686 * @param t The type referred to.
1687 * @returns True if the check completed on all attributed classes
1688 */
1689 private boolean checkNonCyclicInternal(DiagnosticPosition pos, Type t) {
1690 boolean complete = true; // was the check complete?
1691 //- System.err.println("checkNonCyclicInternal("+t+");");//DEBUG
1692 Symbol c = t.tsym;
1693 if ((c.flags_field & ACYCLIC) != 0) return true;
1695 if ((c.flags_field & LOCKED) != 0) {
1696 noteCyclic(pos, (ClassSymbol)c);
1697 } else if (!c.type.isErroneous()) {
1698 try {
1699 c.flags_field |= LOCKED;
1700 if (c.type.tag == CLASS) {
1701 ClassType clazz = (ClassType)c.type;
1702 if (clazz.interfaces_field != null)
1703 for (List<Type> l=clazz.interfaces_field; l.nonEmpty(); l=l.tail)
1704 complete &= checkNonCyclicInternal(pos, l.head);
1705 if (clazz.supertype_field != null) {
1706 Type st = clazz.supertype_field;
1707 if (st != null && st.tag == CLASS)
1708 complete &= checkNonCyclicInternal(pos, st);
1709 }
1710 if (c.owner.kind == TYP)
1711 complete &= checkNonCyclicInternal(pos, c.owner.type);
1712 }
1713 } finally {
1714 c.flags_field &= ~LOCKED;
1715 }
1716 }
1717 if (complete)
1718 complete = ((c.flags_field & UNATTRIBUTED) == 0) && c.completer == null;
1719 if (complete) c.flags_field |= ACYCLIC;
1720 return complete;
1721 }
1723 /** Note that we found an inheritance cycle. */
1724 private void noteCyclic(DiagnosticPosition pos, ClassSymbol c) {
1725 log.error(pos, "cyclic.inheritance", c);
1726 for (List<Type> l=types.interfaces(c.type); l.nonEmpty(); l=l.tail)
1727 l.head = types.createErrorType((ClassSymbol)l.head.tsym, Type.noType);
1728 Type st = types.supertype(c.type);
1729 if (st.tag == CLASS)
1730 ((ClassType)c.type).supertype_field = types.createErrorType((ClassSymbol)st.tsym, Type.noType);
1731 c.type = types.createErrorType(c, c.type);
1732 c.flags_field |= ACYCLIC;
1733 }
1735 /** Check that all methods which implement some
1736 * method conform to the method they implement.
1737 * @param tree The class definition whose members are checked.
1738 */
1739 void checkImplementations(JCClassDecl tree) {
1740 checkImplementations(tree, tree.sym);
1741 }
1742 //where
1743 /** Check that all methods which implement some
1744 * method in `ic' conform to the method they implement.
1745 */
1746 void checkImplementations(JCClassDecl tree, ClassSymbol ic) {
1747 ClassSymbol origin = tree.sym;
1748 for (List<Type> l = types.closure(ic.type); l.nonEmpty(); l = l.tail) {
1749 ClassSymbol lc = (ClassSymbol)l.head.tsym;
1750 if ((allowGenerics || origin != lc) && (lc.flags() & ABSTRACT) != 0) {
1751 for (Scope.Entry e=lc.members().elems; e != null; e=e.sibling) {
1752 if (e.sym.kind == MTH &&
1753 (e.sym.flags() & (STATIC|ABSTRACT)) == ABSTRACT) {
1754 MethodSymbol absmeth = (MethodSymbol)e.sym;
1755 MethodSymbol implmeth = absmeth.implementation(origin, types, false);
1756 if (implmeth != null && implmeth != absmeth &&
1757 (implmeth.owner.flags() & INTERFACE) ==
1758 (origin.flags() & INTERFACE)) {
1759 // don't check if implmeth is in a class, yet
1760 // origin is an interface. This case arises only
1761 // if implmeth is declared in Object. The reason is
1762 // that interfaces really don't inherit from
1763 // Object it's just that the compiler represents
1764 // things that way.
1765 checkOverride(tree, implmeth, absmeth, origin);
1766 }
1767 }
1768 }
1769 }
1770 }
1771 }
1773 /** Check that all abstract methods implemented by a class are
1774 * mutually compatible.
1775 * @param pos Position to be used for error reporting.
1776 * @param c The class whose interfaces are checked.
1777 */
1778 void checkCompatibleSupertypes(DiagnosticPosition pos, Type c) {
1779 List<Type> supertypes = types.interfaces(c);
1780 Type supertype = types.supertype(c);
1781 if (supertype.tag == CLASS &&
1782 (supertype.tsym.flags() & ABSTRACT) != 0)
1783 supertypes = supertypes.prepend(supertype);
1784 for (List<Type> l = supertypes; l.nonEmpty(); l = l.tail) {
1785 if (allowGenerics && !l.head.getTypeArguments().isEmpty() &&
1786 !checkCompatibleAbstracts(pos, l.head, l.head, c))
1787 return;
1788 for (List<Type> m = supertypes; m != l; m = m.tail)
1789 if (!checkCompatibleAbstracts(pos, l.head, m.head, c))
1790 return;
1791 }
1792 checkCompatibleConcretes(pos, c);
1793 }
1795 void checkConflicts(DiagnosticPosition pos, Symbol sym, TypeSymbol c) {
1796 for (Type ct = c.type; ct != Type.noType ; ct = types.supertype(ct)) {
1797 for (Scope.Entry e = ct.tsym.members().lookup(sym.name); e.scope == ct.tsym.members(); e = e.next()) {
1798 // VM allows methods and variables with differing types
1799 if (sym.kind == e.sym.kind &&
1800 types.isSameType(types.erasure(sym.type), types.erasure(e.sym.type)) &&
1801 sym != e.sym &&
1802 (sym.flags() & Flags.SYNTHETIC) != (e.sym.flags() & Flags.SYNTHETIC) &&
1803 (sym.flags() & BRIDGE) == 0 && (e.sym.flags() & BRIDGE) == 0) {
1804 syntheticError(pos, (e.sym.flags() & SYNTHETIC) == 0 ? e.sym : sym);
1805 return;
1806 }
1807 }
1808 }
1809 }
1811 /** Report a conflict between a user symbol and a synthetic symbol.
1812 */
1813 private void syntheticError(DiagnosticPosition pos, Symbol sym) {
1814 if (!sym.type.isErroneous()) {
1815 if (warnOnSyntheticConflicts) {
1816 log.warning(pos, "synthetic.name.conflict", sym, sym.location());
1817 }
1818 else {
1819 log.error(pos, "synthetic.name.conflict", sym, sym.location());
1820 }
1821 }
1822 }
1824 /** Check that class c does not implement directly or indirectly
1825 * the same parameterized interface with two different argument lists.
1826 * @param pos Position to be used for error reporting.
1827 * @param type The type whose interfaces are checked.
1828 */
1829 void checkClassBounds(DiagnosticPosition pos, Type type) {
1830 checkClassBounds(pos, new HashMap<TypeSymbol,Type>(), type);
1831 }
1832 //where
1833 /** Enter all interfaces of type `type' into the hash table `seensofar'
1834 * with their class symbol as key and their type as value. Make
1835 * sure no class is entered with two different types.
1836 */
1837 void checkClassBounds(DiagnosticPosition pos,
1838 Map<TypeSymbol,Type> seensofar,
1839 Type type) {
1840 if (type.isErroneous()) return;
1841 for (List<Type> l = types.interfaces(type); l.nonEmpty(); l = l.tail) {
1842 Type it = l.head;
1843 Type oldit = seensofar.put(it.tsym, it);
1844 if (oldit != null) {
1845 List<Type> oldparams = oldit.allparams();
1846 List<Type> newparams = it.allparams();
1847 if (!types.containsTypeEquivalent(oldparams, newparams))
1848 log.error(pos, "cant.inherit.diff.arg",
1849 it.tsym, Type.toString(oldparams),
1850 Type.toString(newparams));
1851 }
1852 checkClassBounds(pos, seensofar, it);
1853 }
1854 Type st = types.supertype(type);
1855 if (st != null) checkClassBounds(pos, seensofar, st);
1856 }
1858 /** Enter interface into into set.
1859 * If it existed already, issue a "repeated interface" error.
1860 */
1861 void checkNotRepeated(DiagnosticPosition pos, Type it, Set<Type> its) {
1862 if (its.contains(it))
1863 log.error(pos, "repeated.interface");
1864 else {
1865 its.add(it);
1866 }
1867 }
1869 /* *************************************************************************
1870 * Check annotations
1871 **************************************************************************/
1873 /** Annotation types are restricted to primitives, String, an
1874 * enum, an annotation, Class, Class<?>, Class<? extends
1875 * Anything>, arrays of the preceding.
1876 */
1877 void validateAnnotationType(JCTree restype) {
1878 // restype may be null if an error occurred, so don't bother validating it
1879 if (restype != null) {
1880 validateAnnotationType(restype.pos(), restype.type);
1881 }
1882 }
1884 void validateAnnotationType(DiagnosticPosition pos, Type type) {
1885 if (type.isPrimitive()) return;
1886 if (types.isSameType(type, syms.stringType)) return;
1887 if ((type.tsym.flags() & Flags.ENUM) != 0) return;
1888 if ((type.tsym.flags() & Flags.ANNOTATION) != 0) return;
1889 if (types.lowerBound(type).tsym == syms.classType.tsym) return;
1890 if (types.isArray(type) && !types.isArray(types.elemtype(type))) {
1891 validateAnnotationType(pos, types.elemtype(type));
1892 return;
1893 }
1894 log.error(pos, "invalid.annotation.member.type");
1895 }
1897 /**
1898 * "It is also a compile-time error if any method declared in an
1899 * annotation type has a signature that is override-equivalent to
1900 * that of any public or protected method declared in class Object
1901 * or in the interface annotation.Annotation."
1902 *
1903 * @jls3 9.6 Annotation Types
1904 */
1905 void validateAnnotationMethod(DiagnosticPosition pos, MethodSymbol m) {
1906 for (Type sup = syms.annotationType; sup.tag == CLASS; sup = types.supertype(sup)) {
1907 Scope s = sup.tsym.members();
1908 for (Scope.Entry e = s.lookup(m.name); e.scope != null; e = e.next()) {
1909 if (e.sym.kind == MTH &&
1910 (e.sym.flags() & (PUBLIC | PROTECTED)) != 0 &&
1911 types.overrideEquivalent(m.type, e.sym.type))
1912 log.error(pos, "intf.annotation.member.clash", e.sym, sup);
1913 }
1914 }
1915 }
1917 /** Check the annotations of a symbol.
1918 */
1919 public void validateAnnotations(List<JCAnnotation> annotations, Symbol s) {
1920 if (skipAnnotations) return;
1921 for (JCAnnotation a : annotations)
1922 validateAnnotation(a, s);
1923 }
1925 /** Check the type annotations
1926 */
1927 public void validateTypeAnnotations(List<JCTypeAnnotation> annotations, boolean isTypeParameter) {
1928 if (skipAnnotations) return;
1929 for (JCTypeAnnotation a : annotations)
1930 validateTypeAnnotation(a, isTypeParameter);
1931 }
1933 /** Check an annotation of a symbol.
1934 */
1935 public void validateAnnotation(JCAnnotation a, Symbol s) {
1936 validateAnnotation(a);
1938 if (!annotationApplicable(a, s))
1939 log.error(a.pos(), "annotation.type.not.applicable");
1941 if (a.annotationType.type.tsym == syms.overrideType.tsym) {
1942 if (!isOverrider(s))
1943 log.error(a.pos(), "method.does.not.override.superclass");
1944 }
1945 }
1947 public void validateTypeAnnotation(JCTypeAnnotation a, boolean isTypeParameter) {
1948 if (a.type == null)
1949 throw new AssertionError("annotation tree hasn't been attributed yet: " + a);
1950 validateAnnotation(a);
1952 if (!isTypeAnnotation(a, isTypeParameter))
1953 log.error(a.pos(), "annotation.type.not.applicable");
1954 }
1956 /** Is s a method symbol that overrides a method in a superclass? */
1957 boolean isOverrider(Symbol s) {
1958 if (s.kind != MTH || s.isStatic())
1959 return false;
1960 MethodSymbol m = (MethodSymbol)s;
1961 TypeSymbol owner = (TypeSymbol)m.owner;
1962 for (Type sup : types.closure(owner.type)) {
1963 if (sup == owner.type)
1964 continue; // skip "this"
1965 Scope scope = sup.tsym.members();
1966 for (Scope.Entry e = scope.lookup(m.name); e.scope != null; e = e.next()) {
1967 if (!e.sym.isStatic() && m.overrides(e.sym, owner, types, true))
1968 return true;
1969 }
1970 }
1971 return false;
1972 }
1974 /** Is the annotation applicable to type annotations */
1975 boolean isTypeAnnotation(JCTypeAnnotation a, boolean isTypeParameter) {
1976 Attribute.Compound atTarget =
1977 a.annotationType.type.tsym.attribute(syms.annotationTargetType.tsym);
1978 if (atTarget == null) return true;
1979 Attribute atValue = atTarget.member(names.value);
1980 if (!(atValue instanceof Attribute.Array)) return true; // error recovery
1981 Attribute.Array arr = (Attribute.Array) atValue;
1982 for (Attribute app : arr.values) {
1983 if (!(app instanceof Attribute.Enum)) return true; // recovery
1984 Attribute.Enum e = (Attribute.Enum) app;
1985 if (!isTypeParameter && e.value.name == names.TYPE_USE)
1986 return true;
1987 else if (isTypeParameter && e.value.name == names.TYPE_PARAMETER)
1988 return true;
1989 }
1990 return false;
1991 }
1993 /** Is the annotation applicable to the symbol? */
1994 boolean annotationApplicable(JCAnnotation a, Symbol s) {
1995 Attribute.Compound atTarget =
1996 a.annotationType.type.tsym.attribute(syms.annotationTargetType.tsym);
1997 if (atTarget == null) return true;
1998 Attribute atValue = atTarget.member(names.value);
1999 if (!(atValue instanceof Attribute.Array)) return true; // error recovery
2000 Attribute.Array arr = (Attribute.Array) atValue;
2001 for (Attribute app : arr.values) {
2002 if (!(app instanceof Attribute.Enum)) return true; // recovery
2003 Attribute.Enum e = (Attribute.Enum) app;
2004 if (e.value.name == names.TYPE)
2005 { if (s.kind == TYP) return true; }
2006 else if (e.value.name == names.FIELD)
2007 { if (s.kind == VAR && s.owner.kind != MTH) return true; }
2008 else if (e.value.name == names.METHOD)
2009 { if (s.kind == MTH && !s.isConstructor()) return true; }
2010 else if (e.value.name == names.PARAMETER)
2011 { if (s.kind == VAR &&
2012 s.owner.kind == MTH &&
2013 (s.flags() & PARAMETER) != 0)
2014 return true;
2015 }
2016 else if (e.value.name == names.CONSTRUCTOR)
2017 { if (s.kind == MTH && s.isConstructor()) return true; }
2018 else if (e.value.name == names.LOCAL_VARIABLE)
2019 { if (s.kind == VAR && s.owner.kind == MTH &&
2020 (s.flags() & PARAMETER) == 0)
2021 return true;
2022 }
2023 else if (e.value.name == names.ANNOTATION_TYPE)
2024 { if (s.kind == TYP && (s.flags() & ANNOTATION) != 0)
2025 return true;
2026 }
2027 else if (e.value.name == names.PACKAGE)
2028 { if (s.kind == PCK) return true; }
2029 else if (e.value.name == names.TYPE_USE)
2030 { if (s.kind == TYP ||
2031 s.kind == VAR ||
2032 (s.kind == MTH && !s.isConstructor() &&
2033 s.type.getReturnType().tag != VOID))
2034 return true;
2035 }
2036 else
2037 return true; // recovery
2038 }
2039 return false;
2040 }
2042 /** Check an annotation value.
2043 */
2044 public void validateAnnotation(JCAnnotation a) {
2045 if (a.type.isErroneous()) return;
2047 // collect an inventory of the members
2048 Set<MethodSymbol> members = new HashSet<MethodSymbol>();
2049 for (Scope.Entry e = a.annotationType.type.tsym.members().elems;
2050 e != null;
2051 e = e.sibling)
2052 if (e.sym.kind == MTH)
2053 members.add((MethodSymbol) e.sym);
2055 // count them off as they're annotated
2056 for (JCTree arg : a.args) {
2057 if (arg.getTag() != JCTree.ASSIGN) continue; // recovery
2058 JCAssign assign = (JCAssign) arg;
2059 Symbol m = TreeInfo.symbol(assign.lhs);
2060 if (m == null || m.type.isErroneous()) continue;
2061 if (!members.remove(m))
2062 log.error(assign.lhs.pos(), "duplicate.annotation.member.value",
2063 m.name, a.type);
2064 if (assign.rhs.getTag() == ANNOTATION)
2065 validateAnnotation((JCAnnotation)assign.rhs);
2066 }
2068 // all the remaining ones better have default values
2069 for (MethodSymbol m : members)
2070 if (m.defaultValue == null && !m.type.isErroneous())
2071 log.error(a.pos(), "annotation.missing.default.value",
2072 a.type, m.name);
2074 // special case: java.lang.annotation.Target must not have
2075 // repeated values in its value member
2076 if (a.annotationType.type.tsym != syms.annotationTargetType.tsym ||
2077 a.args.tail == null)
2078 return;
2080 if (a.args.head.getTag() != JCTree.ASSIGN) return; // error recovery
2081 JCAssign assign = (JCAssign) a.args.head;
2082 Symbol m = TreeInfo.symbol(assign.lhs);
2083 if (m.name != names.value) return;
2084 JCTree rhs = assign.rhs;
2085 if (rhs.getTag() != JCTree.NEWARRAY) return;
2086 JCNewArray na = (JCNewArray) rhs;
2087 Set<Symbol> targets = new HashSet<Symbol>();
2088 for (JCTree elem : na.elems) {
2089 if (!targets.add(TreeInfo.symbol(elem))) {
2090 log.error(elem.pos(), "repeated.annotation.target");
2091 }
2092 }
2093 }
2095 void checkDeprecatedAnnotation(DiagnosticPosition pos, Symbol s) {
2096 if (allowAnnotations &&
2097 lint.isEnabled(Lint.LintCategory.DEP_ANN) &&
2098 (s.flags() & DEPRECATED) != 0 &&
2099 !syms.deprecatedType.isErroneous() &&
2100 s.attribute(syms.deprecatedType.tsym) == null) {
2101 log.warning(pos, "missing.deprecated.annotation");
2102 }
2103 }
2105 /* *************************************************************************
2106 * Check for recursive annotation elements.
2107 **************************************************************************/
2109 /** Check for cycles in the graph of annotation elements.
2110 */
2111 void checkNonCyclicElements(JCClassDecl tree) {
2112 if ((tree.sym.flags_field & ANNOTATION) == 0) return;
2113 assert (tree.sym.flags_field & LOCKED) == 0;
2114 try {
2115 tree.sym.flags_field |= LOCKED;
2116 for (JCTree def : tree.defs) {
2117 if (def.getTag() != JCTree.METHODDEF) continue;
2118 JCMethodDecl meth = (JCMethodDecl)def;
2119 checkAnnotationResType(meth.pos(), meth.restype.type);
2120 }
2121 } finally {
2122 tree.sym.flags_field &= ~LOCKED;
2123 tree.sym.flags_field |= ACYCLIC_ANN;
2124 }
2125 }
2127 void checkNonCyclicElementsInternal(DiagnosticPosition pos, TypeSymbol tsym) {
2128 if ((tsym.flags_field & ACYCLIC_ANN) != 0)
2129 return;
2130 if ((tsym.flags_field & LOCKED) != 0) {
2131 log.error(pos, "cyclic.annotation.element");
2132 return;
2133 }
2134 try {
2135 tsym.flags_field |= LOCKED;
2136 for (Scope.Entry e = tsym.members().elems; e != null; e = e.sibling) {
2137 Symbol s = e.sym;
2138 if (s.kind != Kinds.MTH)
2139 continue;
2140 checkAnnotationResType(pos, ((MethodSymbol)s).type.getReturnType());
2141 }
2142 } finally {
2143 tsym.flags_field &= ~LOCKED;
2144 tsym.flags_field |= ACYCLIC_ANN;
2145 }
2146 }
2148 void checkAnnotationResType(DiagnosticPosition pos, Type type) {
2149 switch (type.tag) {
2150 case TypeTags.CLASS:
2151 if ((type.tsym.flags() & ANNOTATION) != 0)
2152 checkNonCyclicElementsInternal(pos, type.tsym);
2153 break;
2154 case TypeTags.ARRAY:
2155 checkAnnotationResType(pos, types.elemtype(type));
2156 break;
2157 default:
2158 break; // int etc
2159 }
2160 }
2162 /* *************************************************************************
2163 * Check for cycles in the constructor call graph.
2164 **************************************************************************/
2166 /** Check for cycles in the graph of constructors calling other
2167 * constructors.
2168 */
2169 void checkCyclicConstructors(JCClassDecl tree) {
2170 Map<Symbol,Symbol> callMap = new HashMap<Symbol, Symbol>();
2172 // enter each constructor this-call into the map
2173 for (List<JCTree> l = tree.defs; l.nonEmpty(); l = l.tail) {
2174 JCMethodInvocation app = TreeInfo.firstConstructorCall(l.head);
2175 if (app == null) continue;
2176 JCMethodDecl meth = (JCMethodDecl) l.head;
2177 if (TreeInfo.name(app.meth) == names._this) {
2178 callMap.put(meth.sym, TreeInfo.symbol(app.meth));
2179 } else {
2180 meth.sym.flags_field |= ACYCLIC;
2181 }
2182 }
2184 // Check for cycles in the map
2185 Symbol[] ctors = new Symbol[0];
2186 ctors = callMap.keySet().toArray(ctors);
2187 for (Symbol caller : ctors) {
2188 checkCyclicConstructor(tree, caller, callMap);
2189 }
2190 }
2192 /** Look in the map to see if the given constructor is part of a
2193 * call cycle.
2194 */
2195 private void checkCyclicConstructor(JCClassDecl tree, Symbol ctor,
2196 Map<Symbol,Symbol> callMap) {
2197 if (ctor != null && (ctor.flags_field & ACYCLIC) == 0) {
2198 if ((ctor.flags_field & LOCKED) != 0) {
2199 log.error(TreeInfo.diagnosticPositionFor(ctor, tree),
2200 "recursive.ctor.invocation");
2201 } else {
2202 ctor.flags_field |= LOCKED;
2203 checkCyclicConstructor(tree, callMap.remove(ctor), callMap);
2204 ctor.flags_field &= ~LOCKED;
2205 }
2206 ctor.flags_field |= ACYCLIC;
2207 }
2208 }
2210 /* *************************************************************************
2211 * Miscellaneous
2212 **************************************************************************/
2214 /**
2215 * Return the opcode of the operator but emit an error if it is an
2216 * error.
2217 * @param pos position for error reporting.
2218 * @param operator an operator
2219 * @param tag a tree tag
2220 * @param left type of left hand side
2221 * @param right type of right hand side
2222 */
2223 int checkOperator(DiagnosticPosition pos,
2224 OperatorSymbol operator,
2225 int tag,
2226 Type left,
2227 Type right) {
2228 if (operator.opcode == ByteCodes.error) {
2229 log.error(pos,
2230 "operator.cant.be.applied",
2231 treeinfo.operatorName(tag),
2232 List.of(left, right));
2233 }
2234 return operator.opcode;
2235 }
2238 /**
2239 * Check for division by integer constant zero
2240 * @param pos Position for error reporting.
2241 * @param operator The operator for the expression
2242 * @param operand The right hand operand for the expression
2243 */
2244 void checkDivZero(DiagnosticPosition pos, Symbol operator, Type operand) {
2245 if (operand.constValue() != null
2246 && lint.isEnabled(Lint.LintCategory.DIVZERO)
2247 && operand.tag <= LONG
2248 && ((Number) (operand.constValue())).longValue() == 0) {
2249 int opc = ((OperatorSymbol)operator).opcode;
2250 if (opc == ByteCodes.idiv || opc == ByteCodes.imod
2251 || opc == ByteCodes.ldiv || opc == ByteCodes.lmod) {
2252 log.warning(pos, "div.zero");
2253 }
2254 }
2255 }
2257 /**
2258 * Check for empty statements after if
2259 */
2260 void checkEmptyIf(JCIf tree) {
2261 if (tree.thenpart.getTag() == JCTree.SKIP && tree.elsepart == null && lint.isEnabled(Lint.LintCategory.EMPTY))
2262 log.warning(tree.thenpart.pos(), "empty.if");
2263 }
2265 /** Check that symbol is unique in given scope.
2266 * @param pos Position for error reporting.
2267 * @param sym The symbol.
2268 * @param s The scope.
2269 */
2270 boolean checkUnique(DiagnosticPosition pos, Symbol sym, Scope s) {
2271 if (sym.type.isErroneous())
2272 return true;
2273 if (sym.owner.name == names.any) return false;
2274 for (Scope.Entry e = s.lookup(sym.name); e.scope == s; e = e.next()) {
2275 if (sym != e.sym &&
2276 sym.kind == e.sym.kind &&
2277 sym.name != names.error &&
2278 (sym.kind != MTH || types.hasSameArgs(types.erasure(sym.type), types.erasure(e.sym.type)))) {
2279 if ((sym.flags() & VARARGS) != (e.sym.flags() & VARARGS))
2280 varargsDuplicateError(pos, sym, e.sym);
2281 else if (sym.kind == MTH && !types.overrideEquivalent(sym.type, e.sym.type))
2282 duplicateErasureError(pos, sym, e.sym);
2283 else
2284 duplicateError(pos, e.sym);
2285 return false;
2286 }
2287 }
2288 return true;
2289 }
2290 //where
2291 /** Report duplicate declaration error.
2292 */
2293 void duplicateErasureError(DiagnosticPosition pos, Symbol sym1, Symbol sym2) {
2294 if (!sym1.type.isErroneous() && !sym2.type.isErroneous()) {
2295 log.error(pos, "name.clash.same.erasure", sym1, sym2);
2296 }
2297 }
2299 /** Check that single-type import is not already imported or top-level defined,
2300 * but make an exception for two single-type imports which denote the same type.
2301 * @param pos Position for error reporting.
2302 * @param sym The symbol.
2303 * @param s The scope
2304 */
2305 boolean checkUniqueImport(DiagnosticPosition pos, Symbol sym, Scope s) {
2306 return checkUniqueImport(pos, sym, s, false);
2307 }
2309 /** Check that static single-type import is not already imported or top-level defined,
2310 * but make an exception for two single-type imports which denote the same type.
2311 * @param pos Position for error reporting.
2312 * @param sym The symbol.
2313 * @param s The scope
2314 * @param staticImport Whether or not this was a static import
2315 */
2316 boolean checkUniqueStaticImport(DiagnosticPosition pos, Symbol sym, Scope s) {
2317 return checkUniqueImport(pos, sym, s, true);
2318 }
2320 /** Check that single-type import is not already imported or top-level defined,
2321 * but make an exception for two single-type imports which denote the same type.
2322 * @param pos Position for error reporting.
2323 * @param sym The symbol.
2324 * @param s The scope.
2325 * @param staticImport Whether or not this was a static import
2326 */
2327 private boolean checkUniqueImport(DiagnosticPosition pos, Symbol sym, Scope s, boolean staticImport) {
2328 for (Scope.Entry e = s.lookup(sym.name); e.scope != null; e = e.next()) {
2329 // is encountered class entered via a class declaration?
2330 boolean isClassDecl = e.scope == s;
2331 if ((isClassDecl || sym != e.sym) &&
2332 sym.kind == e.sym.kind &&
2333 sym.name != names.error) {
2334 if (!e.sym.type.isErroneous()) {
2335 String what = e.sym.toString();
2336 if (!isClassDecl) {
2337 if (staticImport)
2338 log.error(pos, "already.defined.static.single.import", what);
2339 else
2340 log.error(pos, "already.defined.single.import", what);
2341 }
2342 else if (sym != e.sym)
2343 log.error(pos, "already.defined.this.unit", what);
2344 }
2345 return false;
2346 }
2347 }
2348 return true;
2349 }
2351 /** Check that a qualified name is in canonical form (for import decls).
2352 */
2353 public void checkCanonical(JCTree tree) {
2354 if (!isCanonical(tree))
2355 log.error(tree.pos(), "import.requires.canonical",
2356 TreeInfo.symbol(tree));
2357 }
2358 // where
2359 private boolean isCanonical(JCTree tree) {
2360 while (tree.getTag() == JCTree.SELECT) {
2361 JCFieldAccess s = (JCFieldAccess) tree;
2362 if (s.sym.owner != TreeInfo.symbol(s.selected))
2363 return false;
2364 tree = s.selected;
2365 }
2366 return true;
2367 }
2369 private class ConversionWarner extends Warner {
2370 final String key;
2371 final Type found;
2372 final Type expected;
2373 public ConversionWarner(DiagnosticPosition pos, String key, Type found, Type expected) {
2374 super(pos);
2375 this.key = key;
2376 this.found = found;
2377 this.expected = expected;
2378 }
2380 @Override
2381 public void warnUnchecked() {
2382 boolean warned = this.warned;
2383 super.warnUnchecked();
2384 if (warned) return; // suppress redundant diagnostics
2385 Object problem = diags.fragment(key);
2386 Check.this.warnUnchecked(pos(), "prob.found.req", problem, found, expected);
2387 }
2388 }
2390 public Warner castWarner(DiagnosticPosition pos, Type found, Type expected) {
2391 return new ConversionWarner(pos, "unchecked.cast.to.type", found, expected);
2392 }
2394 public Warner convertWarner(DiagnosticPosition pos, Type found, Type expected) {
2395 return new ConversionWarner(pos, "unchecked.assign", found, expected);
2396 }
2397 }
