Tue, 05 Mar 2013 14:19:49 +0000
8009129: Illegal access error when calling method reference
Summary: Javac generates method handle referencing non public type
Reviewed-by: jjg, rfield
1 /*
2 * Copyright (c) 1999, 2013, Oracle and/or its affiliates. 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. Oracle designates this
8 * particular file as subject to the "Classpath" exception as provided
9 * by Oracle 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 Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
22 * or visit www.oracle.com if you need additional information or have any
23 * questions.
24 */
26 package com.sun.tools.javac.comp;
28 import java.util.*;
30 import javax.tools.JavaFileManager;
32 import com.sun.tools.javac.code.*;
33 import com.sun.tools.javac.jvm.*;
34 import com.sun.tools.javac.tree.*;
35 import com.sun.tools.javac.util.*;
36 import com.sun.tools.javac.util.JCDiagnostic.DiagnosticPosition;
37 import com.sun.tools.javac.util.List;
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.*;
43 import com.sun.tools.javac.comp.DeferredAttr.DeferredAttrContext;
44 import com.sun.tools.javac.comp.Infer.InferenceContext;
45 import com.sun.tools.javac.comp.Infer.FreeTypeListener;
46 import com.sun.tools.javac.tree.JCTree.*;
47 import com.sun.tools.javac.tree.JCTree.JCPolyExpression.*;
49 import static com.sun.tools.javac.code.Flags.*;
50 import static com.sun.tools.javac.code.Flags.ANNOTATION;
51 import static com.sun.tools.javac.code.Flags.SYNCHRONIZED;
52 import static com.sun.tools.javac.code.Kinds.*;
53 import static com.sun.tools.javac.code.TypeTag.*;
54 import static com.sun.tools.javac.code.TypeTag.WILDCARD;
56 import static com.sun.tools.javac.tree.JCTree.Tag.*;
58 /** Type checking helper class for the attribution phase.
59 *
60 * <p><b>This is NOT part of any supported API.
61 * If you write code that depends on this, you do so at your own risk.
62 * This code and its internal interfaces are subject to change or
63 * deletion without notice.</b>
64 */
65 public class Check {
66 protected static final Context.Key<Check> checkKey =
67 new Context.Key<Check>();
69 private final Names names;
70 private final Log log;
71 private final Resolve rs;
72 private final Symtab syms;
73 private final Enter enter;
74 private final DeferredAttr deferredAttr;
75 private final Infer infer;
76 private final Types types;
77 private final JCDiagnostic.Factory diags;
78 private boolean warnOnSyntheticConflicts;
79 private boolean suppressAbortOnBadClassFile;
80 private boolean enableSunApiLintControl;
81 private final TreeInfo treeinfo;
82 private final JavaFileManager fileManager;
83 private final Profile profile;
85 // The set of lint options currently in effect. It is initialized
86 // from the context, and then is set/reset as needed by Attr as it
87 // visits all the various parts of the trees during attribution.
88 private Lint lint;
90 // The method being analyzed in Attr - it is set/reset as needed by
91 // Attr as it visits new method declarations.
92 private MethodSymbol method;
94 public static Check instance(Context context) {
95 Check instance = context.get(checkKey);
96 if (instance == null)
97 instance = new Check(context);
98 return instance;
99 }
101 protected Check(Context context) {
102 context.put(checkKey, this);
104 names = Names.instance(context);
105 dfltTargetMeta = new Name[] { names.PACKAGE, names.TYPE,
106 names.FIELD, names.METHOD, names.CONSTRUCTOR,
107 names.ANNOTATION_TYPE, names.LOCAL_VARIABLE, names.PARAMETER};
108 log = Log.instance(context);
109 rs = Resolve.instance(context);
110 syms = Symtab.instance(context);
111 enter = Enter.instance(context);
112 deferredAttr = DeferredAttr.instance(context);
113 infer = Infer.instance(context);
114 types = Types.instance(context);
115 diags = JCDiagnostic.Factory.instance(context);
116 Options options = Options.instance(context);
117 lint = Lint.instance(context);
118 treeinfo = TreeInfo.instance(context);
119 fileManager = context.get(JavaFileManager.class);
121 Source source = Source.instance(context);
122 allowGenerics = source.allowGenerics();
123 allowVarargs = source.allowVarargs();
124 allowAnnotations = source.allowAnnotations();
125 allowCovariantReturns = source.allowCovariantReturns();
126 allowSimplifiedVarargs = source.allowSimplifiedVarargs();
127 allowDefaultMethods = source.allowDefaultMethods();
128 allowStrictMethodClashCheck = source.allowStrictMethodClashCheck();
129 complexInference = options.isSet("complexinference");
130 warnOnSyntheticConflicts = options.isSet("warnOnSyntheticConflicts");
131 suppressAbortOnBadClassFile = options.isSet("suppressAbortOnBadClassFile");
132 enableSunApiLintControl = options.isSet("enableSunApiLintControl");
134 Target target = Target.instance(context);
135 syntheticNameChar = target.syntheticNameChar();
137 profile = Profile.instance(context);
139 boolean verboseDeprecated = lint.isEnabled(LintCategory.DEPRECATION);
140 boolean verboseUnchecked = lint.isEnabled(LintCategory.UNCHECKED);
141 boolean verboseSunApi = lint.isEnabled(LintCategory.SUNAPI);
142 boolean enforceMandatoryWarnings = source.enforceMandatoryWarnings();
144 deprecationHandler = new MandatoryWarningHandler(log, verboseDeprecated,
145 enforceMandatoryWarnings, "deprecated", LintCategory.DEPRECATION);
146 uncheckedHandler = new MandatoryWarningHandler(log, verboseUnchecked,
147 enforceMandatoryWarnings, "unchecked", LintCategory.UNCHECKED);
148 sunApiHandler = new MandatoryWarningHandler(log, verboseSunApi,
149 enforceMandatoryWarnings, "sunapi", null);
151 deferredLintHandler = DeferredLintHandler.immediateHandler;
152 }
154 /** Switch: generics enabled?
155 */
156 boolean allowGenerics;
158 /** Switch: varargs enabled?
159 */
160 boolean allowVarargs;
162 /** Switch: annotations enabled?
163 */
164 boolean allowAnnotations;
166 /** Switch: covariant returns enabled?
167 */
168 boolean allowCovariantReturns;
170 /** Switch: simplified varargs enabled?
171 */
172 boolean allowSimplifiedVarargs;
174 /** Switch: default methods enabled?
175 */
176 boolean allowDefaultMethods;
178 /** Switch: should unrelated return types trigger a method clash?
179 */
180 boolean allowStrictMethodClashCheck;
182 /** Switch: -complexinference option set?
183 */
184 boolean complexInference;
186 /** Character for synthetic names
187 */
188 char syntheticNameChar;
190 /** A table mapping flat names of all compiled classes in this run to their
191 * symbols; maintained from outside.
192 */
193 public Map<Name,ClassSymbol> compiled = new HashMap<Name, ClassSymbol>();
195 /** A handler for messages about deprecated usage.
196 */
197 private MandatoryWarningHandler deprecationHandler;
199 /** A handler for messages about unchecked or unsafe usage.
200 */
201 private MandatoryWarningHandler uncheckedHandler;
203 /** A handler for messages about using proprietary API.
204 */
205 private MandatoryWarningHandler sunApiHandler;
207 /** A handler for deferred lint warnings.
208 */
209 private DeferredLintHandler deferredLintHandler;
211 /* *************************************************************************
212 * Errors and Warnings
213 **************************************************************************/
215 Lint setLint(Lint newLint) {
216 Lint prev = lint;
217 lint = newLint;
218 return prev;
219 }
221 DeferredLintHandler setDeferredLintHandler(DeferredLintHandler newDeferredLintHandler) {
222 DeferredLintHandler prev = deferredLintHandler;
223 deferredLintHandler = newDeferredLintHandler;
224 return prev;
225 }
227 MethodSymbol setMethod(MethodSymbol newMethod) {
228 MethodSymbol prev = method;
229 method = newMethod;
230 return prev;
231 }
233 /** Warn about deprecated symbol.
234 * @param pos Position to be used for error reporting.
235 * @param sym The deprecated symbol.
236 */
237 void warnDeprecated(DiagnosticPosition pos, Symbol sym) {
238 if (!lint.isSuppressed(LintCategory.DEPRECATION))
239 deprecationHandler.report(pos, "has.been.deprecated", sym, sym.location());
240 }
242 /** Warn about unchecked operation.
243 * @param pos Position to be used for error reporting.
244 * @param msg A string describing the problem.
245 */
246 public void warnUnchecked(DiagnosticPosition pos, String msg, Object... args) {
247 if (!lint.isSuppressed(LintCategory.UNCHECKED))
248 uncheckedHandler.report(pos, msg, args);
249 }
251 /** Warn about unsafe vararg method decl.
252 * @param pos Position to be used for error reporting.
253 */
254 void warnUnsafeVararg(DiagnosticPosition pos, String key, Object... args) {
255 if (lint.isEnabled(LintCategory.VARARGS) && allowSimplifiedVarargs)
256 log.warning(LintCategory.VARARGS, pos, key, args);
257 }
259 /** Warn about using proprietary API.
260 * @param pos Position to be used for error reporting.
261 * @param msg A string describing the problem.
262 */
263 public void warnSunApi(DiagnosticPosition pos, String msg, Object... args) {
264 if (!lint.isSuppressed(LintCategory.SUNAPI))
265 sunApiHandler.report(pos, msg, args);
266 }
268 public void warnStatic(DiagnosticPosition pos, String msg, Object... args) {
269 if (lint.isEnabled(LintCategory.STATIC))
270 log.warning(LintCategory.STATIC, pos, msg, args);
271 }
273 /**
274 * Report any deferred diagnostics.
275 */
276 public void reportDeferredDiagnostics() {
277 deprecationHandler.reportDeferredDiagnostic();
278 uncheckedHandler.reportDeferredDiagnostic();
279 sunApiHandler.reportDeferredDiagnostic();
280 }
283 /** Report a failure to complete a class.
284 * @param pos Position to be used for error reporting.
285 * @param ex The failure to report.
286 */
287 public Type completionError(DiagnosticPosition pos, CompletionFailure ex) {
288 log.error(JCDiagnostic.DiagnosticFlag.NON_DEFERRABLE, pos, "cant.access", ex.sym, ex.getDetailValue());
289 if (ex instanceof ClassReader.BadClassFile
290 && !suppressAbortOnBadClassFile) throw new Abort();
291 else return syms.errType;
292 }
294 /** Report an error that wrong type tag was found.
295 * @param pos Position to be used for error reporting.
296 * @param required An internationalized string describing the type tag
297 * required.
298 * @param found The type that was found.
299 */
300 Type typeTagError(DiagnosticPosition pos, Object required, Object found) {
301 // this error used to be raised by the parser,
302 // but has been delayed to this point:
303 if (found instanceof Type && ((Type)found).hasTag(VOID)) {
304 log.error(pos, "illegal.start.of.type");
305 return syms.errType;
306 }
307 log.error(pos, "type.found.req", found, required);
308 return types.createErrorType(found instanceof Type ? (Type)found : syms.errType);
309 }
311 /** Report an error that symbol cannot be referenced before super
312 * has been called.
313 * @param pos Position to be used for error reporting.
314 * @param sym The referenced symbol.
315 */
316 void earlyRefError(DiagnosticPosition pos, Symbol sym) {
317 log.error(pos, "cant.ref.before.ctor.called", sym);
318 }
320 /** Report duplicate declaration error.
321 */
322 void duplicateError(DiagnosticPosition pos, Symbol sym) {
323 if (!sym.type.isErroneous()) {
324 Symbol location = sym.location();
325 if (location.kind == MTH &&
326 ((MethodSymbol)location).isStaticOrInstanceInit()) {
327 log.error(pos, "already.defined.in.clinit", kindName(sym), sym,
328 kindName(sym.location()), kindName(sym.location().enclClass()),
329 sym.location().enclClass());
330 } else {
331 log.error(pos, "already.defined", kindName(sym), sym,
332 kindName(sym.location()), sym.location());
333 }
334 }
335 }
337 /** Report array/varargs duplicate declaration
338 */
339 void varargsDuplicateError(DiagnosticPosition pos, Symbol sym1, Symbol sym2) {
340 if (!sym1.type.isErroneous() && !sym2.type.isErroneous()) {
341 log.error(pos, "array.and.varargs", sym1, sym2, sym2.location());
342 }
343 }
345 /* ************************************************************************
346 * duplicate declaration checking
347 *************************************************************************/
349 /** Check that variable does not hide variable with same name in
350 * immediately enclosing local scope.
351 * @param pos Position for error reporting.
352 * @param v The symbol.
353 * @param s The scope.
354 */
355 void checkTransparentVar(DiagnosticPosition pos, VarSymbol v, Scope s) {
356 if (s.next != null) {
357 for (Scope.Entry e = s.next.lookup(v.name);
358 e.scope != null && e.sym.owner == v.owner;
359 e = e.next()) {
360 if (e.sym.kind == VAR &&
361 (e.sym.owner.kind & (VAR | MTH)) != 0 &&
362 v.name != names.error) {
363 duplicateError(pos, e.sym);
364 return;
365 }
366 }
367 }
368 }
370 /** Check that a class or interface does not hide a class or
371 * interface with same name in immediately enclosing local scope.
372 * @param pos Position for error reporting.
373 * @param c The symbol.
374 * @param s The scope.
375 */
376 void checkTransparentClass(DiagnosticPosition pos, ClassSymbol c, Scope s) {
377 if (s.next != null) {
378 for (Scope.Entry e = s.next.lookup(c.name);
379 e.scope != null && e.sym.owner == c.owner;
380 e = e.next()) {
381 if (e.sym.kind == TYP && !e.sym.type.hasTag(TYPEVAR) &&
382 (e.sym.owner.kind & (VAR | MTH)) != 0 &&
383 c.name != names.error) {
384 duplicateError(pos, e.sym);
385 return;
386 }
387 }
388 }
389 }
391 /** Check that class does not have the same name as one of
392 * its enclosing classes, or as a class defined in its enclosing scope.
393 * return true if class is unique in its enclosing scope.
394 * @param pos Position for error reporting.
395 * @param name The class name.
396 * @param s The enclosing scope.
397 */
398 boolean checkUniqueClassName(DiagnosticPosition pos, Name name, Scope s) {
399 for (Scope.Entry e = s.lookup(name); e.scope == s; e = e.next()) {
400 if (e.sym.kind == TYP && e.sym.name != names.error) {
401 duplicateError(pos, e.sym);
402 return false;
403 }
404 }
405 for (Symbol sym = s.owner; sym != null; sym = sym.owner) {
406 if (sym.kind == TYP && sym.name == name && sym.name != names.error) {
407 duplicateError(pos, sym);
408 return true;
409 }
410 }
411 return true;
412 }
414 /* *************************************************************************
415 * Class name generation
416 **************************************************************************/
418 /** Return name of local class.
419 * This is of the form {@code <enclClass> $ n <classname> }
420 * where
421 * enclClass is the flat name of the enclosing class,
422 * classname is the simple name of the local class
423 */
424 Name localClassName(ClassSymbol c) {
425 for (int i=1; ; i++) {
426 Name flatname = names.
427 fromString("" + c.owner.enclClass().flatname +
428 syntheticNameChar + i +
429 c.name);
430 if (compiled.get(flatname) == null) return flatname;
431 }
432 }
434 /* *************************************************************************
435 * Type Checking
436 **************************************************************************/
438 /**
439 * A check context is an object that can be used to perform compatibility
440 * checks - depending on the check context, meaning of 'compatibility' might
441 * vary significantly.
442 */
443 public interface CheckContext {
444 /**
445 * Is type 'found' compatible with type 'req' in given context
446 */
447 boolean compatible(Type found, Type req, Warner warn);
448 /**
449 * Report a check error
450 */
451 void report(DiagnosticPosition pos, JCDiagnostic details);
452 /**
453 * Obtain a warner for this check context
454 */
455 public Warner checkWarner(DiagnosticPosition pos, Type found, Type req);
457 public Infer.InferenceContext inferenceContext();
459 public DeferredAttr.DeferredAttrContext deferredAttrContext();
460 }
462 /**
463 * This class represent a check context that is nested within another check
464 * context - useful to check sub-expressions. The default behavior simply
465 * redirects all method calls to the enclosing check context leveraging
466 * the forwarding pattern.
467 */
468 static class NestedCheckContext implements CheckContext {
469 CheckContext enclosingContext;
471 NestedCheckContext(CheckContext enclosingContext) {
472 this.enclosingContext = enclosingContext;
473 }
475 public boolean compatible(Type found, Type req, Warner warn) {
476 return enclosingContext.compatible(found, req, warn);
477 }
479 public void report(DiagnosticPosition pos, JCDiagnostic details) {
480 enclosingContext.report(pos, details);
481 }
483 public Warner checkWarner(DiagnosticPosition pos, Type found, Type req) {
484 return enclosingContext.checkWarner(pos, found, req);
485 }
487 public Infer.InferenceContext inferenceContext() {
488 return enclosingContext.inferenceContext();
489 }
491 public DeferredAttrContext deferredAttrContext() {
492 return enclosingContext.deferredAttrContext();
493 }
494 }
496 /**
497 * Check context to be used when evaluating assignment/return statements
498 */
499 CheckContext basicHandler = new CheckContext() {
500 public void report(DiagnosticPosition pos, JCDiagnostic details) {
501 log.error(pos, "prob.found.req", details);
502 }
503 public boolean compatible(Type found, Type req, Warner warn) {
504 return types.isAssignable(found, req, warn);
505 }
507 public Warner checkWarner(DiagnosticPosition pos, Type found, Type req) {
508 return convertWarner(pos, found, req);
509 }
511 public InferenceContext inferenceContext() {
512 return infer.emptyContext;
513 }
515 public DeferredAttrContext deferredAttrContext() {
516 return deferredAttr.emptyDeferredAttrContext;
517 }
518 };
520 /** Check that a given type is assignable to a given proto-type.
521 * If it is, return the type, otherwise return errType.
522 * @param pos Position to be used for error reporting.
523 * @param found The type that was found.
524 * @param req The type that was required.
525 */
526 Type checkType(DiagnosticPosition pos, Type found, Type req) {
527 return checkType(pos, found, req, basicHandler);
528 }
530 Type checkType(final DiagnosticPosition pos, final Type found, final Type req, final CheckContext checkContext) {
531 final Infer.InferenceContext inferenceContext = checkContext.inferenceContext();
532 if (inferenceContext.free(req)) {
533 inferenceContext.addFreeTypeListener(List.of(req), new FreeTypeListener() {
534 @Override
535 public void typesInferred(InferenceContext inferenceContext) {
536 checkType(pos, found, inferenceContext.asInstType(req), checkContext);
537 }
538 });
539 }
540 if (req.hasTag(ERROR))
541 return req;
542 if (req.hasTag(NONE))
543 return found;
544 if (checkContext.compatible(found, req, checkContext.checkWarner(pos, found, req))) {
545 return found;
546 } else {
547 if (found.getTag().isSubRangeOf(DOUBLE) && req.getTag().isSubRangeOf(DOUBLE)) {
548 checkContext.report(pos, diags.fragment("possible.loss.of.precision", found, req));
549 return types.createErrorType(found);
550 }
551 checkContext.report(pos, diags.fragment("inconvertible.types", found, req));
552 return types.createErrorType(found);
553 }
554 }
556 /** Check that a given type can be cast to a given target type.
557 * Return the result of the cast.
558 * @param pos Position to be used for error reporting.
559 * @param found The type that is being cast.
560 * @param req The target type of the cast.
561 */
562 Type checkCastable(DiagnosticPosition pos, Type found, Type req) {
563 return checkCastable(pos, found, req, basicHandler);
564 }
565 Type checkCastable(DiagnosticPosition pos, Type found, Type req, CheckContext checkContext) {
566 if (types.isCastable(found, req, castWarner(pos, found, req))) {
567 return req;
568 } else {
569 checkContext.report(pos, diags.fragment("inconvertible.types", found, req));
570 return types.createErrorType(found);
571 }
572 }
574 /** Check for redundant casts (i.e. where source type is a subtype of target type)
575 * The problem should only be reported for non-292 cast
576 */
577 public void checkRedundantCast(Env<AttrContext> env, JCTypeCast tree) {
578 if (!tree.type.isErroneous() &&
579 (env.info.lint == null || env.info.lint.isEnabled(Lint.LintCategory.CAST))
580 && types.isSameType(tree.expr.type, tree.clazz.type)
581 && !(ignoreAnnotatedCasts && TreeInfo.containsTypeAnnotation(tree.clazz))
582 && !is292targetTypeCast(tree)) {
583 log.warning(Lint.LintCategory.CAST,
584 tree.pos(), "redundant.cast", tree.expr.type);
585 }
586 }
587 //where
588 private boolean is292targetTypeCast(JCTypeCast tree) {
589 boolean is292targetTypeCast = false;
590 JCExpression expr = TreeInfo.skipParens(tree.expr);
591 if (expr.hasTag(APPLY)) {
592 JCMethodInvocation apply = (JCMethodInvocation)expr;
593 Symbol sym = TreeInfo.symbol(apply.meth);
594 is292targetTypeCast = sym != null &&
595 sym.kind == MTH &&
596 (sym.flags() & HYPOTHETICAL) != 0;
597 }
598 return is292targetTypeCast;
599 }
601 private static final boolean ignoreAnnotatedCasts = true;
603 /** Check that a type is within some bounds.
604 *
605 * Used in TypeApply to verify that, e.g., X in {@code V<X>} is a valid
606 * type argument.
607 * @param a The type that should be bounded by bs.
608 * @param bound The bound.
609 */
610 private boolean checkExtends(Type a, Type bound) {
611 if (a.isUnbound()) {
612 return true;
613 } else if (!a.hasTag(WILDCARD)) {
614 a = types.upperBound(a);
615 return types.isSubtype(a, bound);
616 } else if (a.isExtendsBound()) {
617 return types.isCastable(bound, types.upperBound(a), types.noWarnings);
618 } else if (a.isSuperBound()) {
619 return !types.notSoftSubtype(types.lowerBound(a), bound);
620 }
621 return true;
622 }
624 /** Check that type is different from 'void'.
625 * @param pos Position to be used for error reporting.
626 * @param t The type to be checked.
627 */
628 Type checkNonVoid(DiagnosticPosition pos, Type t) {
629 if (t.hasTag(VOID)) {
630 log.error(pos, "void.not.allowed.here");
631 return types.createErrorType(t);
632 } else {
633 return t;
634 }
635 }
637 Type checkClassOrArrayType(DiagnosticPosition pos, Type t) {
638 if (!t.hasTag(CLASS) && !t.hasTag(ARRAY) && !t.hasTag(ERROR)) {
639 return typeTagError(pos,
640 diags.fragment("type.req.class.array"),
641 asTypeParam(t));
642 } else {
643 return t;
644 }
645 }
647 /** Check that type is a class or interface type.
648 * @param pos Position to be used for error reporting.
649 * @param t The type to be checked.
650 */
651 Type checkClassType(DiagnosticPosition pos, Type t) {
652 if (!t.hasTag(CLASS) && !t.hasTag(ERROR)) {
653 return typeTagError(pos,
654 diags.fragment("type.req.class"),
655 asTypeParam(t));
656 } else {
657 return t;
658 }
659 }
660 //where
661 private Object asTypeParam(Type t) {
662 return (t.hasTag(TYPEVAR))
663 ? diags.fragment("type.parameter", t)
664 : t;
665 }
667 /** Check that type is a valid qualifier for a constructor reference expression
668 */
669 Type checkConstructorRefType(DiagnosticPosition pos, Type t) {
670 t = checkClassOrArrayType(pos, t);
671 if (t.hasTag(CLASS)) {
672 if ((t.tsym.flags() & (ABSTRACT | INTERFACE)) != 0) {
673 log.error(pos, "abstract.cant.be.instantiated");
674 t = types.createErrorType(t);
675 } else if ((t.tsym.flags() & ENUM) != 0) {
676 log.error(pos, "enum.cant.be.instantiated");
677 t = types.createErrorType(t);
678 }
679 }
680 return t;
681 }
683 /** Check that type is a class or interface type.
684 * @param pos Position to be used for error reporting.
685 * @param t The type to be checked.
686 * @param noBounds True if type bounds are illegal here.
687 */
688 Type checkClassType(DiagnosticPosition pos, Type t, boolean noBounds) {
689 t = checkClassType(pos, t);
690 if (noBounds && t.isParameterized()) {
691 List<Type> args = t.getTypeArguments();
692 while (args.nonEmpty()) {
693 if (args.head.hasTag(WILDCARD))
694 return typeTagError(pos,
695 diags.fragment("type.req.exact"),
696 args.head);
697 args = args.tail;
698 }
699 }
700 return t;
701 }
703 /** Check that type is a reifiable class, interface or array type.
704 * @param pos Position to be used for error reporting.
705 * @param t The type to be checked.
706 */
707 Type checkReifiableReferenceType(DiagnosticPosition pos, Type t) {
708 t = checkClassOrArrayType(pos, t);
709 if (!t.isErroneous() && !types.isReifiable(t)) {
710 log.error(pos, "illegal.generic.type.for.instof");
711 return types.createErrorType(t);
712 } else {
713 return t;
714 }
715 }
717 /** Check that type is a reference type, i.e. a class, interface or array type
718 * or a type variable.
719 * @param pos Position to be used for error reporting.
720 * @param t The type to be checked.
721 */
722 Type checkRefType(DiagnosticPosition pos, Type t) {
723 if (t.isReference())
724 return t;
725 else
726 return typeTagError(pos,
727 diags.fragment("type.req.ref"),
728 t);
729 }
731 /** Check that each type is a reference type, i.e. a class, interface or array type
732 * or a type variable.
733 * @param trees Original trees, used for error reporting.
734 * @param types The types to be checked.
735 */
736 List<Type> checkRefTypes(List<JCExpression> trees, List<Type> types) {
737 List<JCExpression> tl = trees;
738 for (List<Type> l = types; l.nonEmpty(); l = l.tail) {
739 l.head = checkRefType(tl.head.pos(), l.head);
740 tl = tl.tail;
741 }
742 return types;
743 }
745 /** Check that type is a null or reference type.
746 * @param pos Position to be used for error reporting.
747 * @param t The type to be checked.
748 */
749 Type checkNullOrRefType(DiagnosticPosition pos, Type t) {
750 if (t.isNullOrReference())
751 return t;
752 else
753 return typeTagError(pos,
754 diags.fragment("type.req.ref"),
755 t);
756 }
758 /** Check that flag set does not contain elements of two conflicting sets. s
759 * Return true if it doesn't.
760 * @param pos Position to be used for error reporting.
761 * @param flags The set of flags to be checked.
762 * @param set1 Conflicting flags set #1.
763 * @param set2 Conflicting flags set #2.
764 */
765 boolean checkDisjoint(DiagnosticPosition pos, long flags, long set1, long set2) {
766 if ((flags & set1) != 0 && (flags & set2) != 0) {
767 log.error(pos,
768 "illegal.combination.of.modifiers",
769 asFlagSet(TreeInfo.firstFlag(flags & set1)),
770 asFlagSet(TreeInfo.firstFlag(flags & set2)));
771 return false;
772 } else
773 return true;
774 }
776 /** Check that usage of diamond operator is correct (i.e. diamond should not
777 * be used with non-generic classes or in anonymous class creation expressions)
778 */
779 Type checkDiamond(JCNewClass tree, Type t) {
780 if (!TreeInfo.isDiamond(tree) ||
781 t.isErroneous()) {
782 return checkClassType(tree.clazz.pos(), t, true);
783 } else if (tree.def != null) {
784 log.error(tree.clazz.pos(),
785 "cant.apply.diamond.1",
786 t, diags.fragment("diamond.and.anon.class", t));
787 return types.createErrorType(t);
788 } else if (t.tsym.type.getTypeArguments().isEmpty()) {
789 log.error(tree.clazz.pos(),
790 "cant.apply.diamond.1",
791 t, diags.fragment("diamond.non.generic", t));
792 return types.createErrorType(t);
793 } else if (tree.typeargs != null &&
794 tree.typeargs.nonEmpty()) {
795 log.error(tree.clazz.pos(),
796 "cant.apply.diamond.1",
797 t, diags.fragment("diamond.and.explicit.params", t));
798 return types.createErrorType(t);
799 } else {
800 return t;
801 }
802 }
804 void checkVarargsMethodDecl(Env<AttrContext> env, JCMethodDecl tree) {
805 MethodSymbol m = tree.sym;
806 if (!allowSimplifiedVarargs) return;
807 boolean hasTrustMeAnno = m.attribute(syms.trustMeType.tsym) != null;
808 Type varargElemType = null;
809 if (m.isVarArgs()) {
810 varargElemType = types.elemtype(tree.params.last().type);
811 }
812 if (hasTrustMeAnno && !isTrustMeAllowedOnMethod(m)) {
813 if (varargElemType != null) {
814 log.error(tree,
815 "varargs.invalid.trustme.anno",
816 syms.trustMeType.tsym,
817 diags.fragment("varargs.trustme.on.virtual.varargs", m));
818 } else {
819 log.error(tree,
820 "varargs.invalid.trustme.anno",
821 syms.trustMeType.tsym,
822 diags.fragment("varargs.trustme.on.non.varargs.meth", m));
823 }
824 } else if (hasTrustMeAnno && varargElemType != null &&
825 types.isReifiable(varargElemType)) {
826 warnUnsafeVararg(tree,
827 "varargs.redundant.trustme.anno",
828 syms.trustMeType.tsym,
829 diags.fragment("varargs.trustme.on.reifiable.varargs", varargElemType));
830 }
831 else if (!hasTrustMeAnno && varargElemType != null &&
832 !types.isReifiable(varargElemType)) {
833 warnUnchecked(tree.params.head.pos(), "unchecked.varargs.non.reifiable.type", varargElemType);
834 }
835 }
836 //where
837 private boolean isTrustMeAllowedOnMethod(Symbol s) {
838 return (s.flags() & VARARGS) != 0 &&
839 (s.isConstructor() ||
840 (s.flags() & (STATIC | FINAL)) != 0);
841 }
843 Type checkMethod(Type owntype,
844 Symbol sym,
845 Env<AttrContext> env,
846 final List<JCExpression> argtrees,
847 List<Type> argtypes,
848 boolean useVarargs,
849 boolean unchecked) {
850 // System.out.println("call : " + env.tree);
851 // System.out.println("method : " + owntype);
852 // System.out.println("actuals: " + argtypes);
853 List<Type> formals = owntype.getParameterTypes();
854 Type last = useVarargs ? formals.last() : null;
855 if (sym.name == names.init &&
856 sym.owner == syms.enumSym)
857 formals = formals.tail.tail;
858 List<JCExpression> args = argtrees;
859 DeferredAttr.DeferredTypeMap checkDeferredMap =
860 deferredAttr.new DeferredTypeMap(DeferredAttr.AttrMode.CHECK, sym, env.info.pendingResolutionPhase);
861 if (args != null) {
862 //this is null when type-checking a method reference
863 while (formals.head != last) {
864 JCTree arg = args.head;
865 Warner warn = convertWarner(arg.pos(), arg.type, formals.head);
866 assertConvertible(arg, arg.type, formals.head, warn);
867 args = args.tail;
868 formals = formals.tail;
869 }
870 if (useVarargs) {
871 Type varArg = types.elemtype(last);
872 while (args.tail != null) {
873 JCTree arg = args.head;
874 Warner warn = convertWarner(arg.pos(), arg.type, varArg);
875 assertConvertible(arg, arg.type, varArg, warn);
876 args = args.tail;
877 }
878 } else if ((sym.flags() & VARARGS) != 0 && allowVarargs) {
879 // non-varargs call to varargs method
880 Type varParam = owntype.getParameterTypes().last();
881 Type lastArg = checkDeferredMap.apply(argtypes.last());
882 if (types.isSubtypeUnchecked(lastArg, types.elemtype(varParam)) &&
883 !types.isSameType(types.erasure(varParam), types.erasure(lastArg)))
884 log.warning(argtrees.last().pos(), "inexact.non-varargs.call",
885 types.elemtype(varParam), varParam);
886 }
887 }
888 if (unchecked) {
889 warnUnchecked(env.tree.pos(),
890 "unchecked.meth.invocation.applied",
891 kindName(sym),
892 sym.name,
893 rs.methodArguments(sym.type.getParameterTypes()),
894 rs.methodArguments(Type.map(argtypes, checkDeferredMap)),
895 kindName(sym.location()),
896 sym.location());
897 owntype = new MethodType(owntype.getParameterTypes(),
898 types.erasure(owntype.getReturnType()),
899 types.erasure(owntype.getThrownTypes()),
900 syms.methodClass);
901 }
902 if (useVarargs) {
903 Type argtype = owntype.getParameterTypes().last();
904 if (!types.isReifiable(argtype) &&
905 (!allowSimplifiedVarargs ||
906 sym.attribute(syms.trustMeType.tsym) == null ||
907 !isTrustMeAllowedOnMethod(sym))) {
908 warnUnchecked(env.tree.pos(),
909 "unchecked.generic.array.creation",
910 argtype);
911 }
912 if (!((MethodSymbol)sym.baseSymbol()).isSignaturePolymorphic(types)) {
913 TreeInfo.setVarargsElement(env.tree, types.elemtype(argtype));
914 }
915 }
916 PolyKind pkind = (sym.type.hasTag(FORALL) &&
917 sym.type.getReturnType().containsAny(((ForAll)sym.type).tvars)) ?
918 PolyKind.POLY : PolyKind.STANDALONE;
919 TreeInfo.setPolyKind(env.tree, pkind);
920 return owntype;
921 }
922 //where
923 private void assertConvertible(JCTree tree, Type actual, Type formal, Warner warn) {
924 if (types.isConvertible(actual, formal, warn))
925 return;
927 if (formal.isCompound()
928 && types.isSubtype(actual, types.supertype(formal))
929 && types.isSubtypeUnchecked(actual, types.interfaces(formal), warn))
930 return;
931 }
933 /**
934 * Check that type 't' is a valid instantiation of a generic class
935 * (see JLS 4.5)
936 *
937 * @param t class type to be checked
938 * @return true if 't' is well-formed
939 */
940 public boolean checkValidGenericType(Type t) {
941 return firstIncompatibleTypeArg(t) == null;
942 }
943 //WHERE
944 private Type firstIncompatibleTypeArg(Type type) {
945 List<Type> formals = type.tsym.type.allparams();
946 List<Type> actuals = type.allparams();
947 List<Type> args = type.getTypeArguments();
948 List<Type> forms = type.tsym.type.getTypeArguments();
949 ListBuffer<Type> bounds_buf = new ListBuffer<Type>();
951 // For matching pairs of actual argument types `a' and
952 // formal type parameters with declared bound `b' ...
953 while (args.nonEmpty() && forms.nonEmpty()) {
954 // exact type arguments needs to know their
955 // bounds (for upper and lower bound
956 // calculations). So we create new bounds where
957 // type-parameters are replaced with actuals argument types.
958 bounds_buf.append(types.subst(forms.head.getUpperBound(), formals, actuals));
959 args = args.tail;
960 forms = forms.tail;
961 }
963 args = type.getTypeArguments();
964 List<Type> tvars_cap = types.substBounds(formals,
965 formals,
966 types.capture(type).allparams());
967 while (args.nonEmpty() && tvars_cap.nonEmpty()) {
968 // Let the actual arguments know their bound
969 args.head.withTypeVar((TypeVar)tvars_cap.head);
970 args = args.tail;
971 tvars_cap = tvars_cap.tail;
972 }
974 args = type.getTypeArguments();
975 List<Type> bounds = bounds_buf.toList();
977 while (args.nonEmpty() && bounds.nonEmpty()) {
978 Type actual = args.head;
979 if (!isTypeArgErroneous(actual) &&
980 !bounds.head.isErroneous() &&
981 !checkExtends(actual, bounds.head)) {
982 return args.head;
983 }
984 args = args.tail;
985 bounds = bounds.tail;
986 }
988 args = type.getTypeArguments();
989 bounds = bounds_buf.toList();
991 for (Type arg : types.capture(type).getTypeArguments()) {
992 if (arg.hasTag(TYPEVAR) &&
993 arg.getUpperBound().isErroneous() &&
994 !bounds.head.isErroneous() &&
995 !isTypeArgErroneous(args.head)) {
996 return args.head;
997 }
998 bounds = bounds.tail;
999 args = args.tail;
1000 }
1002 return null;
1003 }
1004 //where
1005 boolean isTypeArgErroneous(Type t) {
1006 return isTypeArgErroneous.visit(t);
1007 }
1009 Types.UnaryVisitor<Boolean> isTypeArgErroneous = new Types.UnaryVisitor<Boolean>() {
1010 public Boolean visitType(Type t, Void s) {
1011 return t.isErroneous();
1012 }
1013 @Override
1014 public Boolean visitTypeVar(TypeVar t, Void s) {
1015 return visit(t.getUpperBound());
1016 }
1017 @Override
1018 public Boolean visitCapturedType(CapturedType t, Void s) {
1019 return visit(t.getUpperBound()) ||
1020 visit(t.getLowerBound());
1021 }
1022 @Override
1023 public Boolean visitWildcardType(WildcardType t, Void s) {
1024 return visit(t.type);
1025 }
1026 };
1028 /** Check that given modifiers are legal for given symbol and
1029 * return modifiers together with any implicit modifiers for that symbol.
1030 * Warning: we can't use flags() here since this method
1031 * is called during class enter, when flags() would cause a premature
1032 * completion.
1033 * @param pos Position to be used for error reporting.
1034 * @param flags The set of modifiers given in a definition.
1035 * @param sym The defined symbol.
1036 */
1037 long checkFlags(DiagnosticPosition pos, long flags, Symbol sym, JCTree tree) {
1038 long mask;
1039 long implicit = 0;
1040 switch (sym.kind) {
1041 case VAR:
1042 if (sym.owner.kind != TYP)
1043 mask = LocalVarFlags;
1044 else if ((sym.owner.flags_field & INTERFACE) != 0)
1045 mask = implicit = InterfaceVarFlags;
1046 else
1047 mask = VarFlags;
1048 break;
1049 case MTH:
1050 if (sym.name == names.init) {
1051 if ((sym.owner.flags_field & ENUM) != 0) {
1052 // enum constructors cannot be declared public or
1053 // protected and must be implicitly or explicitly
1054 // private
1055 implicit = PRIVATE;
1056 mask = PRIVATE;
1057 } else
1058 mask = ConstructorFlags;
1059 } else if ((sym.owner.flags_field & INTERFACE) != 0) {
1060 if ((flags & (DEFAULT | STATIC)) != 0) {
1061 mask = InterfaceMethodMask;
1062 implicit = PUBLIC;
1063 if ((flags & DEFAULT) != 0) {
1064 implicit |= ABSTRACT;
1065 }
1066 } else {
1067 mask = implicit = InterfaceMethodFlags;
1068 }
1069 }
1070 else {
1071 mask = MethodFlags;
1072 }
1073 // Imply STRICTFP if owner has STRICTFP set.
1074 if (((flags|implicit) & Flags.ABSTRACT) == 0)
1075 implicit |= sym.owner.flags_field & STRICTFP;
1076 break;
1077 case TYP:
1078 if (sym.isLocal()) {
1079 mask = LocalClassFlags;
1080 if (sym.name.isEmpty()) { // Anonymous class
1081 // Anonymous classes in static methods are themselves static;
1082 // that's why we admit STATIC here.
1083 mask |= STATIC;
1084 // JLS: Anonymous classes are final.
1085 implicit |= FINAL;
1086 }
1087 if ((sym.owner.flags_field & STATIC) == 0 &&
1088 (flags & ENUM) != 0)
1089 log.error(pos, "enums.must.be.static");
1090 } else if (sym.owner.kind == TYP) {
1091 mask = MemberClassFlags;
1092 if (sym.owner.owner.kind == PCK ||
1093 (sym.owner.flags_field & STATIC) != 0)
1094 mask |= STATIC;
1095 else if ((flags & ENUM) != 0)
1096 log.error(pos, "enums.must.be.static");
1097 // Nested interfaces and enums are always STATIC (Spec ???)
1098 if ((flags & (INTERFACE | ENUM)) != 0 ) implicit = STATIC;
1099 } else {
1100 mask = ClassFlags;
1101 }
1102 // Interfaces are always ABSTRACT
1103 if ((flags & INTERFACE) != 0) implicit |= ABSTRACT;
1105 if ((flags & ENUM) != 0) {
1106 // enums can't be declared abstract or final
1107 mask &= ~(ABSTRACT | FINAL);
1108 implicit |= implicitEnumFinalFlag(tree);
1109 }
1110 // Imply STRICTFP if owner has STRICTFP set.
1111 implicit |= sym.owner.flags_field & STRICTFP;
1112 break;
1113 default:
1114 throw new AssertionError();
1115 }
1116 long illegal = flags & ExtendedStandardFlags & ~mask;
1117 if (illegal != 0) {
1118 if ((illegal & INTERFACE) != 0) {
1119 log.error(pos, "intf.not.allowed.here");
1120 mask |= INTERFACE;
1121 }
1122 else {
1123 log.error(pos,
1124 "mod.not.allowed.here", asFlagSet(illegal));
1125 }
1126 }
1127 else if ((sym.kind == TYP ||
1128 // ISSUE: Disallowing abstract&private is no longer appropriate
1129 // in the presence of inner classes. Should it be deleted here?
1130 checkDisjoint(pos, flags,
1131 ABSTRACT,
1132 PRIVATE | STATIC | DEFAULT))
1133 &&
1134 checkDisjoint(pos, flags,
1135 STATIC,
1136 DEFAULT)
1137 &&
1138 checkDisjoint(pos, flags,
1139 ABSTRACT | INTERFACE,
1140 FINAL | NATIVE | SYNCHRONIZED)
1141 &&
1142 checkDisjoint(pos, flags,
1143 PUBLIC,
1144 PRIVATE | PROTECTED)
1145 &&
1146 checkDisjoint(pos, flags,
1147 PRIVATE,
1148 PUBLIC | PROTECTED)
1149 &&
1150 checkDisjoint(pos, flags,
1151 FINAL,
1152 VOLATILE)
1153 &&
1154 (sym.kind == TYP ||
1155 checkDisjoint(pos, flags,
1156 ABSTRACT | NATIVE,
1157 STRICTFP))) {
1158 // skip
1159 }
1160 return flags & (mask | ~ExtendedStandardFlags) | implicit;
1161 }
1164 /** Determine if this enum should be implicitly final.
1165 *
1166 * If the enum has no specialized enum contants, it is final.
1167 *
1168 * If the enum does have specialized enum contants, it is
1169 * <i>not</i> final.
1170 */
1171 private long implicitEnumFinalFlag(JCTree tree) {
1172 if (!tree.hasTag(CLASSDEF)) return 0;
1173 class SpecialTreeVisitor extends JCTree.Visitor {
1174 boolean specialized;
1175 SpecialTreeVisitor() {
1176 this.specialized = false;
1177 };
1179 @Override
1180 public void visitTree(JCTree tree) { /* no-op */ }
1182 @Override
1183 public void visitVarDef(JCVariableDecl tree) {
1184 if ((tree.mods.flags & ENUM) != 0) {
1185 if (tree.init instanceof JCNewClass &&
1186 ((JCNewClass) tree.init).def != null) {
1187 specialized = true;
1188 }
1189 }
1190 }
1191 }
1193 SpecialTreeVisitor sts = new SpecialTreeVisitor();
1194 JCClassDecl cdef = (JCClassDecl) tree;
1195 for (JCTree defs: cdef.defs) {
1196 defs.accept(sts);
1197 if (sts.specialized) return 0;
1198 }
1199 return FINAL;
1200 }
1202 /* *************************************************************************
1203 * Type Validation
1204 **************************************************************************/
1206 /** Validate a type expression. That is,
1207 * check that all type arguments of a parametric type are within
1208 * their bounds. This must be done in a second phase after type attributon
1209 * since a class might have a subclass as type parameter bound. E.g:
1210 *
1211 * <pre>{@code
1212 * class B<A extends C> { ... }
1213 * class C extends B<C> { ... }
1214 * }</pre>
1215 *
1216 * and we can't make sure that the bound is already attributed because
1217 * of possible cycles.
1218 *
1219 * Visitor method: Validate a type expression, if it is not null, catching
1220 * and reporting any completion failures.
1221 */
1222 void validate(JCTree tree, Env<AttrContext> env) {
1223 validate(tree, env, true);
1224 }
1225 void validate(JCTree tree, Env<AttrContext> env, boolean checkRaw) {
1226 new Validator(env).validateTree(tree, checkRaw, true);
1227 }
1229 /** Visitor method: Validate a list of type expressions.
1230 */
1231 void validate(List<? extends JCTree> trees, Env<AttrContext> env) {
1232 for (List<? extends JCTree> l = trees; l.nonEmpty(); l = l.tail)
1233 validate(l.head, env);
1234 }
1236 /** A visitor class for type validation.
1237 */
1238 class Validator extends JCTree.Visitor {
1240 boolean isOuter;
1241 Env<AttrContext> env;
1243 Validator(Env<AttrContext> env) {
1244 this.env = env;
1245 }
1247 @Override
1248 public void visitTypeArray(JCArrayTypeTree tree) {
1249 tree.elemtype.accept(this);
1250 }
1252 @Override
1253 public void visitTypeApply(JCTypeApply tree) {
1254 if (tree.type.hasTag(CLASS)) {
1255 List<JCExpression> args = tree.arguments;
1256 List<Type> forms = tree.type.tsym.type.getTypeArguments();
1258 Type incompatibleArg = firstIncompatibleTypeArg(tree.type);
1259 if (incompatibleArg != null) {
1260 for (JCTree arg : tree.arguments) {
1261 if (arg.type == incompatibleArg) {
1262 log.error(arg, "not.within.bounds", incompatibleArg, forms.head);
1263 }
1264 forms = forms.tail;
1265 }
1266 }
1268 forms = tree.type.tsym.type.getTypeArguments();
1270 boolean is_java_lang_Class = tree.type.tsym.flatName() == names.java_lang_Class;
1272 // For matching pairs of actual argument types `a' and
1273 // formal type parameters with declared bound `b' ...
1274 while (args.nonEmpty() && forms.nonEmpty()) {
1275 validateTree(args.head,
1276 !(isOuter && is_java_lang_Class),
1277 false);
1278 args = args.tail;
1279 forms = forms.tail;
1280 }
1282 // Check that this type is either fully parameterized, or
1283 // not parameterized at all.
1284 if (tree.type.getEnclosingType().isRaw())
1285 log.error(tree.pos(), "improperly.formed.type.inner.raw.param");
1286 if (tree.clazz.hasTag(SELECT))
1287 visitSelectInternal((JCFieldAccess)tree.clazz);
1288 }
1289 }
1291 @Override
1292 public void visitTypeParameter(JCTypeParameter tree) {
1293 validateTrees(tree.bounds, true, isOuter);
1294 checkClassBounds(tree.pos(), tree.type);
1295 }
1297 @Override
1298 public void visitWildcard(JCWildcard tree) {
1299 if (tree.inner != null)
1300 validateTree(tree.inner, true, isOuter);
1301 }
1303 @Override
1304 public void visitSelect(JCFieldAccess tree) {
1305 if (tree.type.hasTag(CLASS)) {
1306 visitSelectInternal(tree);
1308 // Check that this type is either fully parameterized, or
1309 // not parameterized at all.
1310 if (tree.selected.type.isParameterized() && tree.type.tsym.type.getTypeArguments().nonEmpty())
1311 log.error(tree.pos(), "improperly.formed.type.param.missing");
1312 }
1313 }
1315 public void visitSelectInternal(JCFieldAccess tree) {
1316 if (tree.type.tsym.isStatic() &&
1317 tree.selected.type.isParameterized()) {
1318 // The enclosing type is not a class, so we are
1319 // looking at a static member type. However, the
1320 // qualifying expression is parameterized.
1321 log.error(tree.pos(), "cant.select.static.class.from.param.type");
1322 } else {
1323 // otherwise validate the rest of the expression
1324 tree.selected.accept(this);
1325 }
1326 }
1328 @Override
1329 public void visitAnnotatedType(JCAnnotatedType tree) {
1330 tree.underlyingType.accept(this);
1331 }
1333 /** Default visitor method: do nothing.
1334 */
1335 @Override
1336 public void visitTree(JCTree tree) {
1337 }
1339 public void validateTree(JCTree tree, boolean checkRaw, boolean isOuter) {
1340 try {
1341 if (tree != null) {
1342 this.isOuter = isOuter;
1343 tree.accept(this);
1344 if (checkRaw)
1345 checkRaw(tree, env);
1346 }
1347 } catch (CompletionFailure ex) {
1348 completionError(tree.pos(), ex);
1349 }
1350 }
1352 public void validateTrees(List<? extends JCTree> trees, boolean checkRaw, boolean isOuter) {
1353 for (List<? extends JCTree> l = trees; l.nonEmpty(); l = l.tail)
1354 validateTree(l.head, checkRaw, isOuter);
1355 }
1357 void checkRaw(JCTree tree, Env<AttrContext> env) {
1358 if (lint.isEnabled(LintCategory.RAW) &&
1359 tree.type.hasTag(CLASS) &&
1360 !TreeInfo.isDiamond(tree) &&
1361 !withinAnonConstr(env) &&
1362 tree.type.isRaw()) {
1363 log.warning(LintCategory.RAW,
1364 tree.pos(), "raw.class.use", tree.type, tree.type.tsym.type);
1365 }
1366 }
1368 boolean withinAnonConstr(Env<AttrContext> env) {
1369 return env.enclClass.name.isEmpty() &&
1370 env.enclMethod != null && env.enclMethod.name == names.init;
1371 }
1372 }
1374 /* *************************************************************************
1375 * Exception checking
1376 **************************************************************************/
1378 /* The following methods treat classes as sets that contain
1379 * the class itself and all their subclasses
1380 */
1382 /** Is given type a subtype of some of the types in given list?
1383 */
1384 boolean subset(Type t, List<Type> ts) {
1385 for (List<Type> l = ts; l.nonEmpty(); l = l.tail)
1386 if (types.isSubtype(t, l.head)) return true;
1387 return false;
1388 }
1390 /** Is given type a subtype or supertype of
1391 * some of the types in given list?
1392 */
1393 boolean intersects(Type t, List<Type> ts) {
1394 for (List<Type> l = ts; l.nonEmpty(); l = l.tail)
1395 if (types.isSubtype(t, l.head) || types.isSubtype(l.head, t)) return true;
1396 return false;
1397 }
1399 /** Add type set to given type list, unless it is a subclass of some class
1400 * in the list.
1401 */
1402 List<Type> incl(Type t, List<Type> ts) {
1403 return subset(t, ts) ? ts : excl(t, ts).prepend(t);
1404 }
1406 /** Remove type set from type set list.
1407 */
1408 List<Type> excl(Type t, List<Type> ts) {
1409 if (ts.isEmpty()) {
1410 return ts;
1411 } else {
1412 List<Type> ts1 = excl(t, ts.tail);
1413 if (types.isSubtype(ts.head, t)) return ts1;
1414 else if (ts1 == ts.tail) return ts;
1415 else return ts1.prepend(ts.head);
1416 }
1417 }
1419 /** Form the union of two type set lists.
1420 */
1421 List<Type> union(List<Type> ts1, List<Type> ts2) {
1422 List<Type> ts = ts1;
1423 for (List<Type> l = ts2; l.nonEmpty(); l = l.tail)
1424 ts = incl(l.head, ts);
1425 return ts;
1426 }
1428 /** Form the difference of two type lists.
1429 */
1430 List<Type> diff(List<Type> ts1, List<Type> ts2) {
1431 List<Type> ts = ts1;
1432 for (List<Type> l = ts2; l.nonEmpty(); l = l.tail)
1433 ts = excl(l.head, ts);
1434 return ts;
1435 }
1437 /** Form the intersection of two type lists.
1438 */
1439 public List<Type> intersect(List<Type> ts1, List<Type> ts2) {
1440 List<Type> ts = List.nil();
1441 for (List<Type> l = ts1; l.nonEmpty(); l = l.tail)
1442 if (subset(l.head, ts2)) ts = incl(l.head, ts);
1443 for (List<Type> l = ts2; l.nonEmpty(); l = l.tail)
1444 if (subset(l.head, ts1)) ts = incl(l.head, ts);
1445 return ts;
1446 }
1448 /** Is exc an exception symbol that need not be declared?
1449 */
1450 boolean isUnchecked(ClassSymbol exc) {
1451 return
1452 exc.kind == ERR ||
1453 exc.isSubClass(syms.errorType.tsym, types) ||
1454 exc.isSubClass(syms.runtimeExceptionType.tsym, types);
1455 }
1457 /** Is exc an exception type that need not be declared?
1458 */
1459 boolean isUnchecked(Type exc) {
1460 return
1461 (exc.hasTag(TYPEVAR)) ? isUnchecked(types.supertype(exc)) :
1462 (exc.hasTag(CLASS)) ? isUnchecked((ClassSymbol)exc.tsym) :
1463 exc.hasTag(BOT);
1464 }
1466 /** Same, but handling completion failures.
1467 */
1468 boolean isUnchecked(DiagnosticPosition pos, Type exc) {
1469 try {
1470 return isUnchecked(exc);
1471 } catch (CompletionFailure ex) {
1472 completionError(pos, ex);
1473 return true;
1474 }
1475 }
1477 /** Is exc handled by given exception list?
1478 */
1479 boolean isHandled(Type exc, List<Type> handled) {
1480 return isUnchecked(exc) || subset(exc, handled);
1481 }
1483 /** Return all exceptions in thrown list that are not in handled list.
1484 * @param thrown The list of thrown exceptions.
1485 * @param handled The list of handled exceptions.
1486 */
1487 List<Type> unhandled(List<Type> thrown, List<Type> handled) {
1488 List<Type> unhandled = List.nil();
1489 for (List<Type> l = thrown; l.nonEmpty(); l = l.tail)
1490 if (!isHandled(l.head, handled)) unhandled = unhandled.prepend(l.head);
1491 return unhandled;
1492 }
1494 /* *************************************************************************
1495 * Overriding/Implementation checking
1496 **************************************************************************/
1498 /** The level of access protection given by a flag set,
1499 * where PRIVATE is highest and PUBLIC is lowest.
1500 */
1501 static int protection(long flags) {
1502 switch ((short)(flags & AccessFlags)) {
1503 case PRIVATE: return 3;
1504 case PROTECTED: return 1;
1505 default:
1506 case PUBLIC: return 0;
1507 case 0: return 2;
1508 }
1509 }
1511 /** A customized "cannot override" error message.
1512 * @param m The overriding method.
1513 * @param other The overridden method.
1514 * @return An internationalized string.
1515 */
1516 Object cannotOverride(MethodSymbol m, MethodSymbol other) {
1517 String key;
1518 if ((other.owner.flags() & INTERFACE) == 0)
1519 key = "cant.override";
1520 else if ((m.owner.flags() & INTERFACE) == 0)
1521 key = "cant.implement";
1522 else
1523 key = "clashes.with";
1524 return diags.fragment(key, m, m.location(), other, other.location());
1525 }
1527 /** A customized "override" warning message.
1528 * @param m The overriding method.
1529 * @param other The overridden method.
1530 * @return An internationalized string.
1531 */
1532 Object uncheckedOverrides(MethodSymbol m, MethodSymbol other) {
1533 String key;
1534 if ((other.owner.flags() & INTERFACE) == 0)
1535 key = "unchecked.override";
1536 else if ((m.owner.flags() & INTERFACE) == 0)
1537 key = "unchecked.implement";
1538 else
1539 key = "unchecked.clash.with";
1540 return diags.fragment(key, m, m.location(), other, other.location());
1541 }
1543 /** A customized "override" warning message.
1544 * @param m The overriding method.
1545 * @param other The overridden method.
1546 * @return An internationalized string.
1547 */
1548 Object varargsOverrides(MethodSymbol m, MethodSymbol other) {
1549 String key;
1550 if ((other.owner.flags() & INTERFACE) == 0)
1551 key = "varargs.override";
1552 else if ((m.owner.flags() & INTERFACE) == 0)
1553 key = "varargs.implement";
1554 else
1555 key = "varargs.clash.with";
1556 return diags.fragment(key, m, m.location(), other, other.location());
1557 }
1559 /** Check that this method conforms with overridden method 'other'.
1560 * where `origin' is the class where checking started.
1561 * Complications:
1562 * (1) Do not check overriding of synthetic methods
1563 * (reason: they might be final).
1564 * todo: check whether this is still necessary.
1565 * (2) Admit the case where an interface proxy throws fewer exceptions
1566 * than the method it implements. Augment the proxy methods with the
1567 * undeclared exceptions in this case.
1568 * (3) When generics are enabled, admit the case where an interface proxy
1569 * has a result type
1570 * extended by the result type of the method it implements.
1571 * Change the proxies result type to the smaller type in this case.
1572 *
1573 * @param tree The tree from which positions
1574 * are extracted for errors.
1575 * @param m The overriding method.
1576 * @param other The overridden method.
1577 * @param origin The class of which the overriding method
1578 * is a member.
1579 */
1580 void checkOverride(JCTree tree,
1581 MethodSymbol m,
1582 MethodSymbol other,
1583 ClassSymbol origin) {
1584 // Don't check overriding of synthetic methods or by bridge methods.
1585 if ((m.flags() & (SYNTHETIC|BRIDGE)) != 0 || (other.flags() & SYNTHETIC) != 0) {
1586 return;
1587 }
1589 // Error if static method overrides instance method (JLS 8.4.6.2).
1590 if ((m.flags() & STATIC) != 0 &&
1591 (other.flags() & STATIC) == 0) {
1592 log.error(TreeInfo.diagnosticPositionFor(m, tree), "override.static",
1593 cannotOverride(m, other));
1594 m.flags_field |= BAD_OVERRIDE;
1595 return;
1596 }
1598 // Error if instance method overrides static or final
1599 // method (JLS 8.4.6.1).
1600 if ((other.flags() & FINAL) != 0 ||
1601 (m.flags() & STATIC) == 0 &&
1602 (other.flags() & STATIC) != 0) {
1603 log.error(TreeInfo.diagnosticPositionFor(m, tree), "override.meth",
1604 cannotOverride(m, other),
1605 asFlagSet(other.flags() & (FINAL | STATIC)));
1606 m.flags_field |= BAD_OVERRIDE;
1607 return;
1608 }
1610 if ((m.owner.flags() & ANNOTATION) != 0) {
1611 // handled in validateAnnotationMethod
1612 return;
1613 }
1615 // Error if overriding method has weaker access (JLS 8.4.6.3).
1616 if ((origin.flags() & INTERFACE) == 0 &&
1617 protection(m.flags()) > protection(other.flags())) {
1618 log.error(TreeInfo.diagnosticPositionFor(m, tree), "override.weaker.access",
1619 cannotOverride(m, other),
1620 other.flags() == 0 ?
1621 Flag.PACKAGE :
1622 asFlagSet(other.flags() & AccessFlags));
1623 m.flags_field |= BAD_OVERRIDE;
1624 return;
1625 }
1627 Type mt = types.memberType(origin.type, m);
1628 Type ot = types.memberType(origin.type, other);
1629 // Error if overriding result type is different
1630 // (or, in the case of generics mode, not a subtype) of
1631 // overridden result type. We have to rename any type parameters
1632 // before comparing types.
1633 List<Type> mtvars = mt.getTypeArguments();
1634 List<Type> otvars = ot.getTypeArguments();
1635 Type mtres = mt.getReturnType();
1636 Type otres = types.subst(ot.getReturnType(), otvars, mtvars);
1638 overrideWarner.clear();
1639 boolean resultTypesOK =
1640 types.returnTypeSubstitutable(mt, ot, otres, overrideWarner);
1641 if (!resultTypesOK) {
1642 if (!allowCovariantReturns &&
1643 m.owner != origin &&
1644 m.owner.isSubClass(other.owner, types)) {
1645 // allow limited interoperability with covariant returns
1646 } else {
1647 log.error(TreeInfo.diagnosticPositionFor(m, tree),
1648 "override.incompatible.ret",
1649 cannotOverride(m, other),
1650 mtres, otres);
1651 m.flags_field |= BAD_OVERRIDE;
1652 return;
1653 }
1654 } else if (overrideWarner.hasNonSilentLint(LintCategory.UNCHECKED)) {
1655 warnUnchecked(TreeInfo.diagnosticPositionFor(m, tree),
1656 "override.unchecked.ret",
1657 uncheckedOverrides(m, other),
1658 mtres, otres);
1659 }
1661 // Error if overriding method throws an exception not reported
1662 // by overridden method.
1663 List<Type> otthrown = types.subst(ot.getThrownTypes(), otvars, mtvars);
1664 List<Type> unhandledErased = unhandled(mt.getThrownTypes(), types.erasure(otthrown));
1665 List<Type> unhandledUnerased = unhandled(mt.getThrownTypes(), otthrown);
1666 if (unhandledErased.nonEmpty()) {
1667 log.error(TreeInfo.diagnosticPositionFor(m, tree),
1668 "override.meth.doesnt.throw",
1669 cannotOverride(m, other),
1670 unhandledUnerased.head);
1671 m.flags_field |= BAD_OVERRIDE;
1672 return;
1673 }
1674 else if (unhandledUnerased.nonEmpty()) {
1675 warnUnchecked(TreeInfo.diagnosticPositionFor(m, tree),
1676 "override.unchecked.thrown",
1677 cannotOverride(m, other),
1678 unhandledUnerased.head);
1679 return;
1680 }
1682 // Optional warning if varargs don't agree
1683 if ((((m.flags() ^ other.flags()) & Flags.VARARGS) != 0)
1684 && lint.isEnabled(LintCategory.OVERRIDES)) {
1685 log.warning(TreeInfo.diagnosticPositionFor(m, tree),
1686 ((m.flags() & Flags.VARARGS) != 0)
1687 ? "override.varargs.missing"
1688 : "override.varargs.extra",
1689 varargsOverrides(m, other));
1690 }
1692 // Warn if instance method overrides bridge method (compiler spec ??)
1693 if ((other.flags() & BRIDGE) != 0) {
1694 log.warning(TreeInfo.diagnosticPositionFor(m, tree), "override.bridge",
1695 uncheckedOverrides(m, other));
1696 }
1698 // Warn if a deprecated method overridden by a non-deprecated one.
1699 if (!isDeprecatedOverrideIgnorable(other, origin)) {
1700 checkDeprecated(TreeInfo.diagnosticPositionFor(m, tree), m, other);
1701 }
1702 }
1703 // where
1704 private boolean isDeprecatedOverrideIgnorable(MethodSymbol m, ClassSymbol origin) {
1705 // If the method, m, is defined in an interface, then ignore the issue if the method
1706 // is only inherited via a supertype and also implemented in the supertype,
1707 // because in that case, we will rediscover the issue when examining the method
1708 // in the supertype.
1709 // If the method, m, is not defined in an interface, then the only time we need to
1710 // address the issue is when the method is the supertype implemementation: any other
1711 // case, we will have dealt with when examining the supertype classes
1712 ClassSymbol mc = m.enclClass();
1713 Type st = types.supertype(origin.type);
1714 if (!st.hasTag(CLASS))
1715 return true;
1716 MethodSymbol stimpl = m.implementation((ClassSymbol)st.tsym, types, false);
1718 if (mc != null && ((mc.flags() & INTERFACE) != 0)) {
1719 List<Type> intfs = types.interfaces(origin.type);
1720 return (intfs.contains(mc.type) ? false : (stimpl != null));
1721 }
1722 else
1723 return (stimpl != m);
1724 }
1727 // used to check if there were any unchecked conversions
1728 Warner overrideWarner = new Warner();
1730 /** Check that a class does not inherit two concrete methods
1731 * with the same signature.
1732 * @param pos Position to be used for error reporting.
1733 * @param site The class type to be checked.
1734 */
1735 public void checkCompatibleConcretes(DiagnosticPosition pos, Type site) {
1736 Type sup = types.supertype(site);
1737 if (!sup.hasTag(CLASS)) return;
1739 for (Type t1 = sup;
1740 t1.tsym.type.isParameterized();
1741 t1 = types.supertype(t1)) {
1742 for (Scope.Entry e1 = t1.tsym.members().elems;
1743 e1 != null;
1744 e1 = e1.sibling) {
1745 Symbol s1 = e1.sym;
1746 if (s1.kind != MTH ||
1747 (s1.flags() & (STATIC|SYNTHETIC|BRIDGE)) != 0 ||
1748 !s1.isInheritedIn(site.tsym, types) ||
1749 ((MethodSymbol)s1).implementation(site.tsym,
1750 types,
1751 true) != s1)
1752 continue;
1753 Type st1 = types.memberType(t1, s1);
1754 int s1ArgsLength = st1.getParameterTypes().length();
1755 if (st1 == s1.type) continue;
1757 for (Type t2 = sup;
1758 t2.hasTag(CLASS);
1759 t2 = types.supertype(t2)) {
1760 for (Scope.Entry e2 = t2.tsym.members().lookup(s1.name);
1761 e2.scope != null;
1762 e2 = e2.next()) {
1763 Symbol s2 = e2.sym;
1764 if (s2 == s1 ||
1765 s2.kind != MTH ||
1766 (s2.flags() & (STATIC|SYNTHETIC|BRIDGE)) != 0 ||
1767 s2.type.getParameterTypes().length() != s1ArgsLength ||
1768 !s2.isInheritedIn(site.tsym, types) ||
1769 ((MethodSymbol)s2).implementation(site.tsym,
1770 types,
1771 true) != s2)
1772 continue;
1773 Type st2 = types.memberType(t2, s2);
1774 if (types.overrideEquivalent(st1, st2))
1775 log.error(pos, "concrete.inheritance.conflict",
1776 s1, t1, s2, t2, sup);
1777 }
1778 }
1779 }
1780 }
1781 }
1783 /** Check that classes (or interfaces) do not each define an abstract
1784 * method with same name and arguments but incompatible return types.
1785 * @param pos Position to be used for error reporting.
1786 * @param t1 The first argument type.
1787 * @param t2 The second argument type.
1788 */
1789 public boolean checkCompatibleAbstracts(DiagnosticPosition pos,
1790 Type t1,
1791 Type t2) {
1792 return checkCompatibleAbstracts(pos, t1, t2,
1793 types.makeCompoundType(t1, t2));
1794 }
1796 public boolean checkCompatibleAbstracts(DiagnosticPosition pos,
1797 Type t1,
1798 Type t2,
1799 Type site) {
1800 return firstIncompatibility(pos, t1, t2, site) == null;
1801 }
1803 /** Return the first method which is defined with same args
1804 * but different return types in two given interfaces, or null if none
1805 * exists.
1806 * @param t1 The first type.
1807 * @param t2 The second type.
1808 * @param site The most derived type.
1809 * @returns symbol from t2 that conflicts with one in t1.
1810 */
1811 private Symbol firstIncompatibility(DiagnosticPosition pos, Type t1, Type t2, Type site) {
1812 Map<TypeSymbol,Type> interfaces1 = new HashMap<TypeSymbol,Type>();
1813 closure(t1, interfaces1);
1814 Map<TypeSymbol,Type> interfaces2;
1815 if (t1 == t2)
1816 interfaces2 = interfaces1;
1817 else
1818 closure(t2, interfaces1, interfaces2 = new HashMap<TypeSymbol,Type>());
1820 for (Type t3 : interfaces1.values()) {
1821 for (Type t4 : interfaces2.values()) {
1822 Symbol s = firstDirectIncompatibility(pos, t3, t4, site);
1823 if (s != null) return s;
1824 }
1825 }
1826 return null;
1827 }
1829 /** Compute all the supertypes of t, indexed by type symbol. */
1830 private void closure(Type t, Map<TypeSymbol,Type> typeMap) {
1831 if (!t.hasTag(CLASS)) return;
1832 if (typeMap.put(t.tsym, t) == null) {
1833 closure(types.supertype(t), typeMap);
1834 for (Type i : types.interfaces(t))
1835 closure(i, typeMap);
1836 }
1837 }
1839 /** Compute all the supertypes of t, indexed by type symbol (except thise in typesSkip). */
1840 private void closure(Type t, Map<TypeSymbol,Type> typesSkip, Map<TypeSymbol,Type> typeMap) {
1841 if (!t.hasTag(CLASS)) return;
1842 if (typesSkip.get(t.tsym) != null) return;
1843 if (typeMap.put(t.tsym, t) == null) {
1844 closure(types.supertype(t), typesSkip, typeMap);
1845 for (Type i : types.interfaces(t))
1846 closure(i, typesSkip, typeMap);
1847 }
1848 }
1850 /** Return the first method in t2 that conflicts with a method from t1. */
1851 private Symbol firstDirectIncompatibility(DiagnosticPosition pos, Type t1, Type t2, Type site) {
1852 for (Scope.Entry e1 = t1.tsym.members().elems; e1 != null; e1 = e1.sibling) {
1853 Symbol s1 = e1.sym;
1854 Type st1 = null;
1855 if (s1.kind != MTH || !s1.isInheritedIn(site.tsym, types) ||
1856 (s1.flags() & SYNTHETIC) != 0) continue;
1857 Symbol impl = ((MethodSymbol)s1).implementation(site.tsym, types, false);
1858 if (impl != null && (impl.flags() & ABSTRACT) == 0) continue;
1859 for (Scope.Entry e2 = t2.tsym.members().lookup(s1.name); e2.scope != null; e2 = e2.next()) {
1860 Symbol s2 = e2.sym;
1861 if (s1 == s2) continue;
1862 if (s2.kind != MTH || !s2.isInheritedIn(site.tsym, types) ||
1863 (s2.flags() & SYNTHETIC) != 0) continue;
1864 if (st1 == null) st1 = types.memberType(t1, s1);
1865 Type st2 = types.memberType(t2, s2);
1866 if (types.overrideEquivalent(st1, st2)) {
1867 List<Type> tvars1 = st1.getTypeArguments();
1868 List<Type> tvars2 = st2.getTypeArguments();
1869 Type rt1 = st1.getReturnType();
1870 Type rt2 = types.subst(st2.getReturnType(), tvars2, tvars1);
1871 boolean compat =
1872 types.isSameType(rt1, rt2) ||
1873 !rt1.isPrimitiveOrVoid() &&
1874 !rt2.isPrimitiveOrVoid() &&
1875 (types.covariantReturnType(rt1, rt2, types.noWarnings) ||
1876 types.covariantReturnType(rt2, rt1, types.noWarnings)) ||
1877 checkCommonOverriderIn(s1,s2,site);
1878 if (!compat) {
1879 log.error(pos, "types.incompatible.diff.ret",
1880 t1, t2, s2.name +
1881 "(" + types.memberType(t2, s2).getParameterTypes() + ")");
1882 return s2;
1883 }
1884 } else if (checkNameClash((ClassSymbol)site.tsym, s1, s2) &&
1885 !checkCommonOverriderIn(s1, s2, site)) {
1886 log.error(pos,
1887 "name.clash.same.erasure.no.override",
1888 s1, s1.location(),
1889 s2, s2.location());
1890 return s2;
1891 }
1892 }
1893 }
1894 return null;
1895 }
1896 //WHERE
1897 boolean checkCommonOverriderIn(Symbol s1, Symbol s2, Type site) {
1898 Map<TypeSymbol,Type> supertypes = new HashMap<TypeSymbol,Type>();
1899 Type st1 = types.memberType(site, s1);
1900 Type st2 = types.memberType(site, s2);
1901 closure(site, supertypes);
1902 for (Type t : supertypes.values()) {
1903 for (Scope.Entry e = t.tsym.members().lookup(s1.name); e.scope != null; e = e.next()) {
1904 Symbol s3 = e.sym;
1905 if (s3 == s1 || s3 == s2 || s3.kind != MTH || (s3.flags() & (BRIDGE|SYNTHETIC)) != 0) continue;
1906 Type st3 = types.memberType(site,s3);
1907 if (types.overrideEquivalent(st3, st1) && types.overrideEquivalent(st3, st2)) {
1908 if (s3.owner == site.tsym) {
1909 return true;
1910 }
1911 List<Type> tvars1 = st1.getTypeArguments();
1912 List<Type> tvars2 = st2.getTypeArguments();
1913 List<Type> tvars3 = st3.getTypeArguments();
1914 Type rt1 = st1.getReturnType();
1915 Type rt2 = st2.getReturnType();
1916 Type rt13 = types.subst(st3.getReturnType(), tvars3, tvars1);
1917 Type rt23 = types.subst(st3.getReturnType(), tvars3, tvars2);
1918 boolean compat =
1919 !rt13.isPrimitiveOrVoid() &&
1920 !rt23.isPrimitiveOrVoid() &&
1921 (types.covariantReturnType(rt13, rt1, types.noWarnings) &&
1922 types.covariantReturnType(rt23, rt2, types.noWarnings));
1923 if (compat)
1924 return true;
1925 }
1926 }
1927 }
1928 return false;
1929 }
1931 /** Check that a given method conforms with any method it overrides.
1932 * @param tree The tree from which positions are extracted
1933 * for errors.
1934 * @param m The overriding method.
1935 */
1936 void checkOverride(JCTree tree, MethodSymbol m) {
1937 ClassSymbol origin = (ClassSymbol)m.owner;
1938 if ((origin.flags() & ENUM) != 0 && names.finalize.equals(m.name))
1939 if (m.overrides(syms.enumFinalFinalize, origin, types, false)) {
1940 log.error(tree.pos(), "enum.no.finalize");
1941 return;
1942 }
1943 for (Type t = origin.type; t.hasTag(CLASS);
1944 t = types.supertype(t)) {
1945 if (t != origin.type) {
1946 checkOverride(tree, t, origin, m);
1947 }
1948 for (Type t2 : types.interfaces(t)) {
1949 checkOverride(tree, t2, origin, m);
1950 }
1951 }
1952 }
1954 void checkOverride(JCTree tree, Type site, ClassSymbol origin, MethodSymbol m) {
1955 TypeSymbol c = site.tsym;
1956 Scope.Entry e = c.members().lookup(m.name);
1957 while (e.scope != null) {
1958 if (m.overrides(e.sym, origin, types, false)) {
1959 if ((e.sym.flags() & ABSTRACT) == 0) {
1960 checkOverride(tree, m, (MethodSymbol)e.sym, origin);
1961 }
1962 }
1963 e = e.next();
1964 }
1965 }
1967 private Filter<Symbol> equalsHasCodeFilter = new Filter<Symbol>() {
1968 public boolean accepts(Symbol s) {
1969 return MethodSymbol.implementation_filter.accepts(s) &&
1970 (s.flags() & BAD_OVERRIDE) == 0;
1972 }
1973 };
1975 public void checkClassOverrideEqualsAndHash(DiagnosticPosition pos,
1976 ClassSymbol someClass) {
1977 if (lint.isEnabled(LintCategory.OVERRIDES)) {
1978 MethodSymbol equalsAtObject = (MethodSymbol)syms.objectType
1979 .tsym.members().lookup(names.equals).sym;
1980 MethodSymbol hashCodeAtObject = (MethodSymbol)syms.objectType
1981 .tsym.members().lookup(names.hashCode).sym;
1983 boolean overridesEquals = types.implementation(equalsAtObject,
1984 someClass, false, equalsHasCodeFilter).owner == someClass;
1985 boolean overridesHashCode = types.implementation(hashCodeAtObject,
1986 someClass, false, equalsHasCodeFilter) != hashCodeAtObject;
1988 if (overridesEquals && !overridesHashCode) {
1989 log.warning(LintCategory.OVERRIDES, pos,
1990 "override.equals.but.not.hashcode", someClass.fullname);
1991 }
1992 }
1993 }
1995 private boolean checkNameClash(ClassSymbol origin, Symbol s1, Symbol s2) {
1996 ClashFilter cf = new ClashFilter(origin.type);
1997 return (cf.accepts(s1) &&
1998 cf.accepts(s2) &&
1999 types.hasSameArgs(s1.erasure(types), s2.erasure(types)));
2000 }
2003 /** Check that all abstract members of given class have definitions.
2004 * @param pos Position to be used for error reporting.
2005 * @param c The class.
2006 */
2007 void checkAllDefined(DiagnosticPosition pos, ClassSymbol c) {
2008 try {
2009 MethodSymbol undef = firstUndef(c, c);
2010 if (undef != null) {
2011 if ((c.flags() & ENUM) != 0 &&
2012 types.supertype(c.type).tsym == syms.enumSym &&
2013 (c.flags() & FINAL) == 0) {
2014 // add the ABSTRACT flag to an enum
2015 c.flags_field |= ABSTRACT;
2016 } else {
2017 MethodSymbol undef1 =
2018 new MethodSymbol(undef.flags(), undef.name,
2019 types.memberType(c.type, undef), undef.owner);
2020 log.error(pos, "does.not.override.abstract",
2021 c, undef1, undef1.location());
2022 }
2023 }
2024 } catch (CompletionFailure ex) {
2025 completionError(pos, ex);
2026 }
2027 }
2028 //where
2029 /** Return first abstract member of class `c' that is not defined
2030 * in `impl', null if there is none.
2031 */
2032 private MethodSymbol firstUndef(ClassSymbol impl, ClassSymbol c) {
2033 MethodSymbol undef = null;
2034 // Do not bother to search in classes that are not abstract,
2035 // since they cannot have abstract members.
2036 if (c == impl || (c.flags() & (ABSTRACT | INTERFACE)) != 0) {
2037 Scope s = c.members();
2038 for (Scope.Entry e = s.elems;
2039 undef == null && e != null;
2040 e = e.sibling) {
2041 if (e.sym.kind == MTH &&
2042 (e.sym.flags() & (ABSTRACT|IPROXY|DEFAULT)) == ABSTRACT) {
2043 MethodSymbol absmeth = (MethodSymbol)e.sym;
2044 MethodSymbol implmeth = absmeth.implementation(impl, types, true);
2045 if (implmeth == null || implmeth == absmeth) {
2046 //look for default implementations
2047 if (allowDefaultMethods) {
2048 MethodSymbol prov = types.interfaceCandidates(impl.type, absmeth).head;
2049 if (prov != null && prov.overrides(absmeth, impl, types, true)) {
2050 implmeth = prov;
2051 }
2052 }
2053 }
2054 if (implmeth == null || implmeth == absmeth) {
2055 undef = absmeth;
2056 }
2057 }
2058 }
2059 if (undef == null) {
2060 Type st = types.supertype(c.type);
2061 if (st.hasTag(CLASS))
2062 undef = firstUndef(impl, (ClassSymbol)st.tsym);
2063 }
2064 for (List<Type> l = types.interfaces(c.type);
2065 undef == null && l.nonEmpty();
2066 l = l.tail) {
2067 undef = firstUndef(impl, (ClassSymbol)l.head.tsym);
2068 }
2069 }
2070 return undef;
2071 }
2073 void checkNonCyclicDecl(JCClassDecl tree) {
2074 CycleChecker cc = new CycleChecker();
2075 cc.scan(tree);
2076 if (!cc.errorFound && !cc.partialCheck) {
2077 tree.sym.flags_field |= ACYCLIC;
2078 }
2079 }
2081 class CycleChecker extends TreeScanner {
2083 List<Symbol> seenClasses = List.nil();
2084 boolean errorFound = false;
2085 boolean partialCheck = false;
2087 private void checkSymbol(DiagnosticPosition pos, Symbol sym) {
2088 if (sym != null && sym.kind == TYP) {
2089 Env<AttrContext> classEnv = enter.getEnv((TypeSymbol)sym);
2090 if (classEnv != null) {
2091 DiagnosticSource prevSource = log.currentSource();
2092 try {
2093 log.useSource(classEnv.toplevel.sourcefile);
2094 scan(classEnv.tree);
2095 }
2096 finally {
2097 log.useSource(prevSource.getFile());
2098 }
2099 } else if (sym.kind == TYP) {
2100 checkClass(pos, sym, List.<JCTree>nil());
2101 }
2102 } else {
2103 //not completed yet
2104 partialCheck = true;
2105 }
2106 }
2108 @Override
2109 public void visitSelect(JCFieldAccess tree) {
2110 super.visitSelect(tree);
2111 checkSymbol(tree.pos(), tree.sym);
2112 }
2114 @Override
2115 public void visitIdent(JCIdent tree) {
2116 checkSymbol(tree.pos(), tree.sym);
2117 }
2119 @Override
2120 public void visitTypeApply(JCTypeApply tree) {
2121 scan(tree.clazz);
2122 }
2124 @Override
2125 public void visitTypeArray(JCArrayTypeTree tree) {
2126 scan(tree.elemtype);
2127 }
2129 @Override
2130 public void visitClassDef(JCClassDecl tree) {
2131 List<JCTree> supertypes = List.nil();
2132 if (tree.getExtendsClause() != null) {
2133 supertypes = supertypes.prepend(tree.getExtendsClause());
2134 }
2135 if (tree.getImplementsClause() != null) {
2136 for (JCTree intf : tree.getImplementsClause()) {
2137 supertypes = supertypes.prepend(intf);
2138 }
2139 }
2140 checkClass(tree.pos(), tree.sym, supertypes);
2141 }
2143 void checkClass(DiagnosticPosition pos, Symbol c, List<JCTree> supertypes) {
2144 if ((c.flags_field & ACYCLIC) != 0)
2145 return;
2146 if (seenClasses.contains(c)) {
2147 errorFound = true;
2148 noteCyclic(pos, (ClassSymbol)c);
2149 } else if (!c.type.isErroneous()) {
2150 try {
2151 seenClasses = seenClasses.prepend(c);
2152 if (c.type.hasTag(CLASS)) {
2153 if (supertypes.nonEmpty()) {
2154 scan(supertypes);
2155 }
2156 else {
2157 ClassType ct = (ClassType)c.type;
2158 if (ct.supertype_field == null ||
2159 ct.interfaces_field == null) {
2160 //not completed yet
2161 partialCheck = true;
2162 return;
2163 }
2164 checkSymbol(pos, ct.supertype_field.tsym);
2165 for (Type intf : ct.interfaces_field) {
2166 checkSymbol(pos, intf.tsym);
2167 }
2168 }
2169 if (c.owner.kind == TYP) {
2170 checkSymbol(pos, c.owner);
2171 }
2172 }
2173 } finally {
2174 seenClasses = seenClasses.tail;
2175 }
2176 }
2177 }
2178 }
2180 /** Check for cyclic references. Issue an error if the
2181 * symbol of the type referred to has a LOCKED flag set.
2182 *
2183 * @param pos Position to be used for error reporting.
2184 * @param t The type referred to.
2185 */
2186 void checkNonCyclic(DiagnosticPosition pos, Type t) {
2187 checkNonCyclicInternal(pos, t);
2188 }
2191 void checkNonCyclic(DiagnosticPosition pos, TypeVar t) {
2192 checkNonCyclic1(pos, t, List.<TypeVar>nil());
2193 }
2195 private void checkNonCyclic1(DiagnosticPosition pos, Type t, List<TypeVar> seen) {
2196 final TypeVar tv;
2197 if (t.hasTag(TYPEVAR) && (t.tsym.flags() & UNATTRIBUTED) != 0)
2198 return;
2199 if (seen.contains(t)) {
2200 tv = (TypeVar)t;
2201 tv.bound = types.createErrorType(t);
2202 log.error(pos, "cyclic.inheritance", t);
2203 } else if (t.hasTag(TYPEVAR)) {
2204 tv = (TypeVar)t;
2205 seen = seen.prepend(tv);
2206 for (Type b : types.getBounds(tv))
2207 checkNonCyclic1(pos, b, seen);
2208 }
2209 }
2211 /** Check for cyclic references. Issue an error if the
2212 * symbol of the type referred to has a LOCKED flag set.
2213 *
2214 * @param pos Position to be used for error reporting.
2215 * @param t The type referred to.
2216 * @returns True if the check completed on all attributed classes
2217 */
2218 private boolean checkNonCyclicInternal(DiagnosticPosition pos, Type t) {
2219 boolean complete = true; // was the check complete?
2220 //- System.err.println("checkNonCyclicInternal("+t+");");//DEBUG
2221 Symbol c = t.tsym;
2222 if ((c.flags_field & ACYCLIC) != 0) return true;
2224 if ((c.flags_field & LOCKED) != 0) {
2225 noteCyclic(pos, (ClassSymbol)c);
2226 } else if (!c.type.isErroneous()) {
2227 try {
2228 c.flags_field |= LOCKED;
2229 if (c.type.hasTag(CLASS)) {
2230 ClassType clazz = (ClassType)c.type;
2231 if (clazz.interfaces_field != null)
2232 for (List<Type> l=clazz.interfaces_field; l.nonEmpty(); l=l.tail)
2233 complete &= checkNonCyclicInternal(pos, l.head);
2234 if (clazz.supertype_field != null) {
2235 Type st = clazz.supertype_field;
2236 if (st != null && st.hasTag(CLASS))
2237 complete &= checkNonCyclicInternal(pos, st);
2238 }
2239 if (c.owner.kind == TYP)
2240 complete &= checkNonCyclicInternal(pos, c.owner.type);
2241 }
2242 } finally {
2243 c.flags_field &= ~LOCKED;
2244 }
2245 }
2246 if (complete)
2247 complete = ((c.flags_field & UNATTRIBUTED) == 0) && c.completer == null;
2248 if (complete) c.flags_field |= ACYCLIC;
2249 return complete;
2250 }
2252 /** Note that we found an inheritance cycle. */
2253 private void noteCyclic(DiagnosticPosition pos, ClassSymbol c) {
2254 log.error(pos, "cyclic.inheritance", c);
2255 for (List<Type> l=types.interfaces(c.type); l.nonEmpty(); l=l.tail)
2256 l.head = types.createErrorType((ClassSymbol)l.head.tsym, Type.noType);
2257 Type st = types.supertype(c.type);
2258 if (st.hasTag(CLASS))
2259 ((ClassType)c.type).supertype_field = types.createErrorType((ClassSymbol)st.tsym, Type.noType);
2260 c.type = types.createErrorType(c, c.type);
2261 c.flags_field |= ACYCLIC;
2262 }
2264 /**
2265 * Check that functional interface methods would make sense when seen
2266 * from the perspective of the implementing class
2267 */
2268 void checkFunctionalInterface(JCTree tree, Type funcInterface) {
2269 ClassType c = new ClassType(Type.noType, List.<Type>nil(), null);
2270 ClassSymbol csym = new ClassSymbol(0, names.empty, c, syms.noSymbol);
2271 c.interfaces_field = List.of(types.removeWildcards(funcInterface));
2272 c.supertype_field = syms.objectType;
2273 c.tsym = csym;
2274 csym.members_field = new Scope(csym);
2275 Symbol descSym = types.findDescriptorSymbol(funcInterface.tsym);
2276 Type descType = types.findDescriptorType(funcInterface);
2277 csym.members_field.enter(new MethodSymbol(PUBLIC, descSym.name, descType, csym));
2278 csym.completer = null;
2279 checkImplementations(tree, csym, csym);
2280 }
2282 /** Check that all methods which implement some
2283 * method conform to the method they implement.
2284 * @param tree The class definition whose members are checked.
2285 */
2286 void checkImplementations(JCClassDecl tree) {
2287 checkImplementations(tree, tree.sym, tree.sym);
2288 }
2289 //where
2290 /** Check that all methods which implement some
2291 * method in `ic' conform to the method they implement.
2292 */
2293 void checkImplementations(JCTree tree, ClassSymbol origin, ClassSymbol ic) {
2294 for (List<Type> l = types.closure(ic.type); l.nonEmpty(); l = l.tail) {
2295 ClassSymbol lc = (ClassSymbol)l.head.tsym;
2296 if ((allowGenerics || origin != lc) && (lc.flags() & ABSTRACT) != 0) {
2297 for (Scope.Entry e=lc.members().elems; e != null; e=e.sibling) {
2298 if (e.sym.kind == MTH &&
2299 (e.sym.flags() & (STATIC|ABSTRACT)) == ABSTRACT) {
2300 MethodSymbol absmeth = (MethodSymbol)e.sym;
2301 MethodSymbol implmeth = absmeth.implementation(origin, types, false);
2302 if (implmeth != null && implmeth != absmeth &&
2303 (implmeth.owner.flags() & INTERFACE) ==
2304 (origin.flags() & INTERFACE)) {
2305 // don't check if implmeth is in a class, yet
2306 // origin is an interface. This case arises only
2307 // if implmeth is declared in Object. The reason is
2308 // that interfaces really don't inherit from
2309 // Object it's just that the compiler represents
2310 // things that way.
2311 checkOverride(tree, implmeth, absmeth, origin);
2312 }
2313 }
2314 }
2315 }
2316 }
2317 }
2319 /** Check that all abstract methods implemented by a class are
2320 * mutually compatible.
2321 * @param pos Position to be used for error reporting.
2322 * @param c The class whose interfaces are checked.
2323 */
2324 void checkCompatibleSupertypes(DiagnosticPosition pos, Type c) {
2325 List<Type> supertypes = types.interfaces(c);
2326 Type supertype = types.supertype(c);
2327 if (supertype.hasTag(CLASS) &&
2328 (supertype.tsym.flags() & ABSTRACT) != 0)
2329 supertypes = supertypes.prepend(supertype);
2330 for (List<Type> l = supertypes; l.nonEmpty(); l = l.tail) {
2331 if (allowGenerics && !l.head.getTypeArguments().isEmpty() &&
2332 !checkCompatibleAbstracts(pos, l.head, l.head, c))
2333 return;
2334 for (List<Type> m = supertypes; m != l; m = m.tail)
2335 if (!checkCompatibleAbstracts(pos, l.head, m.head, c))
2336 return;
2337 }
2338 checkCompatibleConcretes(pos, c);
2339 }
2341 void checkConflicts(DiagnosticPosition pos, Symbol sym, TypeSymbol c) {
2342 for (Type ct = c.type; ct != Type.noType ; ct = types.supertype(ct)) {
2343 for (Scope.Entry e = ct.tsym.members().lookup(sym.name); e.scope == ct.tsym.members(); e = e.next()) {
2344 // VM allows methods and variables with differing types
2345 if (sym.kind == e.sym.kind &&
2346 types.isSameType(types.erasure(sym.type), types.erasure(e.sym.type)) &&
2347 sym != e.sym &&
2348 (sym.flags() & Flags.SYNTHETIC) != (e.sym.flags() & Flags.SYNTHETIC) &&
2349 (sym.flags() & IPROXY) == 0 && (e.sym.flags() & IPROXY) == 0 &&
2350 (sym.flags() & BRIDGE) == 0 && (e.sym.flags() & BRIDGE) == 0) {
2351 syntheticError(pos, (e.sym.flags() & SYNTHETIC) == 0 ? e.sym : sym);
2352 return;
2353 }
2354 }
2355 }
2356 }
2358 /** Check that all non-override equivalent methods accessible from 'site'
2359 * are mutually compatible (JLS 8.4.8/9.4.1).
2360 *
2361 * @param pos Position to be used for error reporting.
2362 * @param site The class whose methods are checked.
2363 * @param sym The method symbol to be checked.
2364 */
2365 void checkOverrideClashes(DiagnosticPosition pos, Type site, MethodSymbol sym) {
2366 ClashFilter cf = new ClashFilter(site);
2367 //for each method m1 that is overridden (directly or indirectly)
2368 //by method 'sym' in 'site'...
2369 for (Symbol m1 : types.membersClosure(site, false).getElementsByName(sym.name, cf)) {
2370 if (!sym.overrides(m1, site.tsym, types, false)) continue;
2371 //...check each method m2 that is a member of 'site'
2372 for (Symbol m2 : types.membersClosure(site, false).getElementsByName(sym.name, cf)) {
2373 if (m2 == m1) continue;
2374 //if (i) the signature of 'sym' is not a subsignature of m1 (seen as
2375 //a member of 'site') and (ii) m1 has the same erasure as m2, issue an error
2376 if (!types.isSubSignature(sym.type, types.memberType(site, m2), allowStrictMethodClashCheck) &&
2377 types.hasSameArgs(m2.erasure(types), m1.erasure(types))) {
2378 sym.flags_field |= CLASH;
2379 String key = m1 == sym ?
2380 "name.clash.same.erasure.no.override" :
2381 "name.clash.same.erasure.no.override.1";
2382 log.error(pos,
2383 key,
2384 sym, sym.location(),
2385 m2, m2.location(),
2386 m1, m1.location());
2387 return;
2388 }
2389 }
2390 }
2391 }
2395 /** Check that all static methods accessible from 'site' are
2396 * mutually compatible (JLS 8.4.8).
2397 *
2398 * @param pos Position to be used for error reporting.
2399 * @param site The class whose methods are checked.
2400 * @param sym The method symbol to be checked.
2401 */
2402 void checkHideClashes(DiagnosticPosition pos, Type site, MethodSymbol sym) {
2403 ClashFilter cf = new ClashFilter(site);
2404 //for each method m1 that is a member of 'site'...
2405 for (Symbol s : types.membersClosure(site, true).getElementsByName(sym.name, cf)) {
2406 //if (i) the signature of 'sym' is not a subsignature of m1 (seen as
2407 //a member of 'site') and (ii) 'sym' has the same erasure as m1, issue an error
2408 if (!types.isSubSignature(sym.type, types.memberType(site, s), allowStrictMethodClashCheck) &&
2409 types.hasSameArgs(s.erasure(types), sym.erasure(types))) {
2410 log.error(pos,
2411 "name.clash.same.erasure.no.hide",
2412 sym, sym.location(),
2413 s, s.location());
2414 return;
2415 }
2416 }
2417 }
2419 //where
2420 private class ClashFilter implements Filter<Symbol> {
2422 Type site;
2424 ClashFilter(Type site) {
2425 this.site = site;
2426 }
2428 boolean shouldSkip(Symbol s) {
2429 return (s.flags() & CLASH) != 0 &&
2430 s.owner == site.tsym;
2431 }
2433 public boolean accepts(Symbol s) {
2434 return s.kind == MTH &&
2435 (s.flags() & SYNTHETIC) == 0 &&
2436 !shouldSkip(s) &&
2437 s.isInheritedIn(site.tsym, types) &&
2438 !s.isConstructor();
2439 }
2440 }
2442 void checkDefaultMethodClashes(DiagnosticPosition pos, Type site) {
2443 DefaultMethodClashFilter dcf = new DefaultMethodClashFilter(site);
2444 for (Symbol m : types.membersClosure(site, false).getElements(dcf)) {
2445 Assert.check(m.kind == MTH);
2446 List<MethodSymbol> prov = types.interfaceCandidates(site, (MethodSymbol)m);
2447 if (prov.size() > 1) {
2448 ListBuffer<Symbol> abstracts = ListBuffer.lb();
2449 ListBuffer<Symbol> defaults = ListBuffer.lb();
2450 for (MethodSymbol provSym : prov) {
2451 if ((provSym.flags() & DEFAULT) != 0) {
2452 defaults = defaults.append(provSym);
2453 } else if ((provSym.flags() & ABSTRACT) != 0) {
2454 abstracts = abstracts.append(provSym);
2455 }
2456 if (defaults.nonEmpty() && defaults.size() + abstracts.size() >= 2) {
2457 //strong semantics - issue an error if two sibling interfaces
2458 //have two override-equivalent defaults - or if one is abstract
2459 //and the other is default
2460 String errKey;
2461 Symbol s1 = defaults.first();
2462 Symbol s2;
2463 if (defaults.size() > 1) {
2464 errKey = "types.incompatible.unrelated.defaults";
2465 s2 = defaults.toList().tail.head;
2466 } else {
2467 errKey = "types.incompatible.abstract.default";
2468 s2 = abstracts.first();
2469 }
2470 log.error(pos, errKey,
2471 Kinds.kindName(site.tsym), site,
2472 m.name, types.memberType(site, m).getParameterTypes(),
2473 s1.location(), s2.location());
2474 break;
2475 }
2476 }
2477 }
2478 }
2479 }
2481 //where
2482 private class DefaultMethodClashFilter implements Filter<Symbol> {
2484 Type site;
2486 DefaultMethodClashFilter(Type site) {
2487 this.site = site;
2488 }
2490 public boolean accepts(Symbol s) {
2491 return s.kind == MTH &&
2492 (s.flags() & DEFAULT) != 0 &&
2493 s.isInheritedIn(site.tsym, types) &&
2494 !s.isConstructor();
2495 }
2496 }
2498 /** Report a conflict between a user symbol and a synthetic symbol.
2499 */
2500 private void syntheticError(DiagnosticPosition pos, Symbol sym) {
2501 if (!sym.type.isErroneous()) {
2502 if (warnOnSyntheticConflicts) {
2503 log.warning(pos, "synthetic.name.conflict", sym, sym.location());
2504 }
2505 else {
2506 log.error(pos, "synthetic.name.conflict", sym, sym.location());
2507 }
2508 }
2509 }
2511 /** Check that class c does not implement directly or indirectly
2512 * the same parameterized interface with two different argument lists.
2513 * @param pos Position to be used for error reporting.
2514 * @param type The type whose interfaces are checked.
2515 */
2516 void checkClassBounds(DiagnosticPosition pos, Type type) {
2517 checkClassBounds(pos, new HashMap<TypeSymbol,Type>(), type);
2518 }
2519 //where
2520 /** Enter all interfaces of type `type' into the hash table `seensofar'
2521 * with their class symbol as key and their type as value. Make
2522 * sure no class is entered with two different types.
2523 */
2524 void checkClassBounds(DiagnosticPosition pos,
2525 Map<TypeSymbol,Type> seensofar,
2526 Type type) {
2527 if (type.isErroneous()) return;
2528 for (List<Type> l = types.interfaces(type); l.nonEmpty(); l = l.tail) {
2529 Type it = l.head;
2530 Type oldit = seensofar.put(it.tsym, it);
2531 if (oldit != null) {
2532 List<Type> oldparams = oldit.allparams();
2533 List<Type> newparams = it.allparams();
2534 if (!types.containsTypeEquivalent(oldparams, newparams))
2535 log.error(pos, "cant.inherit.diff.arg",
2536 it.tsym, Type.toString(oldparams),
2537 Type.toString(newparams));
2538 }
2539 checkClassBounds(pos, seensofar, it);
2540 }
2541 Type st = types.supertype(type);
2542 if (st != null) checkClassBounds(pos, seensofar, st);
2543 }
2545 /** Enter interface into into set.
2546 * If it existed already, issue a "repeated interface" error.
2547 */
2548 void checkNotRepeated(DiagnosticPosition pos, Type it, Set<Type> its) {
2549 if (its.contains(it))
2550 log.error(pos, "repeated.interface");
2551 else {
2552 its.add(it);
2553 }
2554 }
2556 /* *************************************************************************
2557 * Check annotations
2558 **************************************************************************/
2560 /**
2561 * Recursively validate annotations values
2562 */
2563 void validateAnnotationTree(JCTree tree) {
2564 class AnnotationValidator extends TreeScanner {
2565 @Override
2566 public void visitAnnotation(JCAnnotation tree) {
2567 if (!tree.type.isErroneous()) {
2568 super.visitAnnotation(tree);
2569 validateAnnotation(tree);
2570 }
2571 }
2572 }
2573 tree.accept(new AnnotationValidator());
2574 }
2576 /**
2577 * {@literal
2578 * Annotation types are restricted to primitives, String, an
2579 * enum, an annotation, Class, Class<?>, Class<? extends
2580 * Anything>, arrays of the preceding.
2581 * }
2582 */
2583 void validateAnnotationType(JCTree restype) {
2584 // restype may be null if an error occurred, so don't bother validating it
2585 if (restype != null) {
2586 validateAnnotationType(restype.pos(), restype.type);
2587 }
2588 }
2590 void validateAnnotationType(DiagnosticPosition pos, Type type) {
2591 if (type.isPrimitive()) return;
2592 if (types.isSameType(type, syms.stringType)) return;
2593 if ((type.tsym.flags() & Flags.ENUM) != 0) return;
2594 if ((type.tsym.flags() & Flags.ANNOTATION) != 0) return;
2595 if (types.lowerBound(type).tsym == syms.classType.tsym) return;
2596 if (types.isArray(type) && !types.isArray(types.elemtype(type))) {
2597 validateAnnotationType(pos, types.elemtype(type));
2598 return;
2599 }
2600 log.error(pos, "invalid.annotation.member.type");
2601 }
2603 /**
2604 * "It is also a compile-time error if any method declared in an
2605 * annotation type has a signature that is override-equivalent to
2606 * that of any public or protected method declared in class Object
2607 * or in the interface annotation.Annotation."
2608 *
2609 * @jls 9.6 Annotation Types
2610 */
2611 void validateAnnotationMethod(DiagnosticPosition pos, MethodSymbol m) {
2612 for (Type sup = syms.annotationType; sup.hasTag(CLASS); sup = types.supertype(sup)) {
2613 Scope s = sup.tsym.members();
2614 for (Scope.Entry e = s.lookup(m.name); e.scope != null; e = e.next()) {
2615 if (e.sym.kind == MTH &&
2616 (e.sym.flags() & (PUBLIC | PROTECTED)) != 0 &&
2617 types.overrideEquivalent(m.type, e.sym.type))
2618 log.error(pos, "intf.annotation.member.clash", e.sym, sup);
2619 }
2620 }
2621 }
2623 /** Check the annotations of a symbol.
2624 */
2625 public void validateAnnotations(List<JCAnnotation> annotations, Symbol s) {
2626 for (JCAnnotation a : annotations)
2627 validateAnnotation(a, s);
2628 }
2630 /** Check the type annotations.
2631 */
2632 public void validateTypeAnnotations(List<JCAnnotation> annotations, boolean isTypeParameter) {
2633 for (JCAnnotation a : annotations)
2634 validateTypeAnnotation(a, isTypeParameter);
2635 }
2637 /** Check an annotation of a symbol.
2638 */
2639 private void validateAnnotation(JCAnnotation a, Symbol s) {
2640 validateAnnotationTree(a);
2642 if (!annotationApplicable(a, s))
2643 log.error(a.pos(), "annotation.type.not.applicable");
2645 if (a.annotationType.type.tsym == syms.overrideType.tsym) {
2646 if (!isOverrider(s))
2647 log.error(a.pos(), "method.does.not.override.superclass");
2648 }
2650 if (a.annotationType.type.tsym == syms.functionalInterfaceType.tsym) {
2651 if (s.kind != TYP) {
2652 log.error(a.pos(), "bad.functional.intf.anno");
2653 } else {
2654 try {
2655 types.findDescriptorSymbol((TypeSymbol)s);
2656 } catch (Types.FunctionDescriptorLookupError ex) {
2657 log.error(a.pos(), "bad.functional.intf.anno.1", ex.getDiagnostic());
2658 }
2659 }
2660 }
2661 }
2663 public void validateTypeAnnotation(JCAnnotation a, boolean isTypeParameter) {
2664 Assert.checkNonNull(a.type, "annotation tree hasn't been attributed yet: " + a);
2665 validateAnnotationTree(a);
2667 if (!isTypeAnnotation(a, isTypeParameter))
2668 log.error(a.pos(), "annotation.type.not.applicable");
2669 }
2671 /**
2672 * Validate the proposed container 'repeatable' on the
2673 * annotation type symbol 's'. Report errors at position
2674 * 'pos'.
2675 *
2676 * @param s The (annotation)type declaration annotated with a @Repeatable
2677 * @param repeatable the @Repeatable on 's'
2678 * @param pos where to report errors
2679 */
2680 public void validateRepeatable(TypeSymbol s, Attribute.Compound repeatable, DiagnosticPosition pos) {
2681 Assert.check(types.isSameType(repeatable.type, syms.repeatableType));
2683 Type t = null;
2684 List<Pair<MethodSymbol,Attribute>> l = repeatable.values;
2685 if (!l.isEmpty()) {
2686 Assert.check(l.head.fst.name == names.value);
2687 t = ((Attribute.Class)l.head.snd).getValue();
2688 }
2690 if (t == null) {
2691 // errors should already have been reported during Annotate
2692 return;
2693 }
2695 validateValue(t.tsym, s, pos);
2696 validateRetention(t.tsym, s, pos);
2697 validateDocumented(t.tsym, s, pos);
2698 validateInherited(t.tsym, s, pos);
2699 validateTarget(t.tsym, s, pos);
2700 validateDefault(t.tsym, s, pos);
2701 }
2703 private void validateValue(TypeSymbol container, TypeSymbol contained, DiagnosticPosition pos) {
2704 Scope.Entry e = container.members().lookup(names.value);
2705 if (e.scope != null && e.sym.kind == MTH) {
2706 MethodSymbol m = (MethodSymbol) e.sym;
2707 Type ret = m.getReturnType();
2708 if (!(ret.hasTag(ARRAY) && types.isSameType(((ArrayType)ret).elemtype, contained.type))) {
2709 log.error(pos, "invalid.repeatable.annotation.value.return",
2710 container, ret, types.makeArrayType(contained.type));
2711 }
2712 } else {
2713 log.error(pos, "invalid.repeatable.annotation.no.value", container);
2714 }
2715 }
2717 private void validateRetention(Symbol container, Symbol contained, DiagnosticPosition pos) {
2718 Attribute.RetentionPolicy containerRetention = types.getRetention(container);
2719 Attribute.RetentionPolicy containedRetention = types.getRetention(contained);
2721 boolean error = false;
2722 switch (containedRetention) {
2723 case RUNTIME:
2724 if (containerRetention != Attribute.RetentionPolicy.RUNTIME) {
2725 error = true;
2726 }
2727 break;
2728 case CLASS:
2729 if (containerRetention == Attribute.RetentionPolicy.SOURCE) {
2730 error = true;
2731 }
2732 }
2733 if (error ) {
2734 log.error(pos, "invalid.repeatable.annotation.retention",
2735 container, containerRetention,
2736 contained, containedRetention);
2737 }
2738 }
2740 private void validateDocumented(Symbol container, Symbol contained, DiagnosticPosition pos) {
2741 if (contained.attribute(syms.documentedType.tsym) != null) {
2742 if (container.attribute(syms.documentedType.tsym) == null) {
2743 log.error(pos, "invalid.repeatable.annotation.not.documented", container, contained);
2744 }
2745 }
2746 }
2748 private void validateInherited(Symbol container, Symbol contained, DiagnosticPosition pos) {
2749 if (contained.attribute(syms.inheritedType.tsym) != null) {
2750 if (container.attribute(syms.inheritedType.tsym) == null) {
2751 log.error(pos, "invalid.repeatable.annotation.not.inherited", container, contained);
2752 }
2753 }
2754 }
2756 private void validateTarget(Symbol container, Symbol contained, DiagnosticPosition pos) {
2757 Attribute.Array containedTarget = getAttributeTargetAttribute(contained);
2759 // If contained has no Target, we are done
2760 if (containedTarget == null) {
2761 return;
2762 }
2764 // If contained has Target m1, container must have a Target
2765 // annotation, m2, and m2 must be a subset of m1. (This is
2766 // trivially true if contained has no target as per above).
2768 // contained has target, but container has not, error
2769 Attribute.Array containerTarget = getAttributeTargetAttribute(container);
2770 if (containerTarget == null) {
2771 log.error(pos, "invalid.repeatable.annotation.incompatible.target", container, contained);
2772 return;
2773 }
2775 Set<Name> containerTargets = new HashSet<Name>();
2776 for (Attribute app : containerTarget.values) {
2777 if (!(app instanceof Attribute.Enum)) {
2778 continue; // recovery
2779 }
2780 Attribute.Enum e = (Attribute.Enum)app;
2781 containerTargets.add(e.value.name);
2782 }
2784 Set<Name> containedTargets = new HashSet<Name>();
2785 for (Attribute app : containedTarget.values) {
2786 if (!(app instanceof Attribute.Enum)) {
2787 continue; // recovery
2788 }
2789 Attribute.Enum e = (Attribute.Enum)app;
2790 containedTargets.add(e.value.name);
2791 }
2793 if (!isTargetSubset(containedTargets, containerTargets)) {
2794 log.error(pos, "invalid.repeatable.annotation.incompatible.target", container, contained);
2795 }
2796 }
2798 /** Checks that t is a subset of s, with respect to ElementType
2799 * semantics, specifically {ANNOTATION_TYPE} is a subset of {TYPE}
2800 */
2801 private boolean isTargetSubset(Set<Name> s, Set<Name> t) {
2802 // Check that all elements in t are present in s
2803 for (Name n2 : t) {
2804 boolean currentElementOk = false;
2805 for (Name n1 : s) {
2806 if (n1 == n2) {
2807 currentElementOk = true;
2808 break;
2809 } else if (n1 == names.TYPE && n2 == names.ANNOTATION_TYPE) {
2810 currentElementOk = true;
2811 break;
2812 }
2813 }
2814 if (!currentElementOk)
2815 return false;
2816 }
2817 return true;
2818 }
2820 private void validateDefault(Symbol container, Symbol contained, DiagnosticPosition pos) {
2821 // validate that all other elements of containing type has defaults
2822 Scope scope = container.members();
2823 for(Symbol elm : scope.getElements()) {
2824 if (elm.name != names.value &&
2825 elm.kind == Kinds.MTH &&
2826 ((MethodSymbol)elm).defaultValue == null) {
2827 log.error(pos,
2828 "invalid.repeatable.annotation.elem.nondefault",
2829 container,
2830 elm);
2831 }
2832 }
2833 }
2835 /** Is s a method symbol that overrides a method in a superclass? */
2836 boolean isOverrider(Symbol s) {
2837 if (s.kind != MTH || s.isStatic())
2838 return false;
2839 MethodSymbol m = (MethodSymbol)s;
2840 TypeSymbol owner = (TypeSymbol)m.owner;
2841 for (Type sup : types.closure(owner.type)) {
2842 if (sup == owner.type)
2843 continue; // skip "this"
2844 Scope scope = sup.tsym.members();
2845 for (Scope.Entry e = scope.lookup(m.name); e.scope != null; e = e.next()) {
2846 if (!e.sym.isStatic() && m.overrides(e.sym, owner, types, true))
2847 return true;
2848 }
2849 }
2850 return false;
2851 }
2853 /** Is the annotation applicable to type annotations? */
2854 protected boolean isTypeAnnotation(JCAnnotation a, boolean isTypeParameter) {
2855 Attribute.Compound atTarget =
2856 a.annotationType.type.tsym.attribute(syms.annotationTargetType.tsym);
2857 if (atTarget == null) {
2858 // An annotation without @Target is not a type annotation.
2859 return false;
2860 }
2862 Attribute atValue = atTarget.member(names.value);
2863 if (!(atValue instanceof Attribute.Array)) {
2864 return false; // error recovery
2865 }
2867 Attribute.Array arr = (Attribute.Array) atValue;
2868 for (Attribute app : arr.values) {
2869 if (!(app instanceof Attribute.Enum)) {
2870 return false; // recovery
2871 }
2872 Attribute.Enum e = (Attribute.Enum) app;
2874 if (e.value.name == names.TYPE_USE)
2875 return true;
2876 else if (isTypeParameter && e.value.name == names.TYPE_PARAMETER)
2877 return true;
2878 }
2879 return false;
2880 }
2882 /** Is the annotation applicable to the symbol? */
2883 boolean annotationApplicable(JCAnnotation a, Symbol s) {
2884 Attribute.Array arr = getAttributeTargetAttribute(a.annotationType.type.tsym);
2885 Name[] targets;
2887 if (arr == null) {
2888 targets = defaultTargetMetaInfo(a, s);
2889 } else {
2890 // TODO: can we optimize this?
2891 targets = new Name[arr.values.length];
2892 for (int i=0; i<arr.values.length; ++i) {
2893 Attribute app = arr.values[i];
2894 if (!(app instanceof Attribute.Enum)) {
2895 return true; // recovery
2896 }
2897 Attribute.Enum e = (Attribute.Enum) app;
2898 targets[i] = e.value.name;
2899 }
2900 }
2901 for (Name target : targets) {
2902 if (target == names.TYPE)
2903 { if (s.kind == TYP) return true; }
2904 else if (target == names.FIELD)
2905 { if (s.kind == VAR && s.owner.kind != MTH) return true; }
2906 else if (target == names.METHOD)
2907 { if (s.kind == MTH && !s.isConstructor()) return true; }
2908 else if (target == names.PARAMETER)
2909 { if (s.kind == VAR &&
2910 s.owner.kind == MTH &&
2911 (s.flags() & PARAMETER) != 0)
2912 return true;
2913 }
2914 else if (target == names.CONSTRUCTOR)
2915 { if (s.kind == MTH && s.isConstructor()) return true; }
2916 else if (target == names.LOCAL_VARIABLE)
2917 { if (s.kind == VAR && s.owner.kind == MTH &&
2918 (s.flags() & PARAMETER) == 0)
2919 return true;
2920 }
2921 else if (target == names.ANNOTATION_TYPE)
2922 { if (s.kind == TYP && (s.flags() & ANNOTATION) != 0)
2923 return true;
2924 }
2925 else if (target == names.PACKAGE)
2926 { if (s.kind == PCK) return true; }
2927 else if (target == names.TYPE_USE)
2928 { if (s.kind == TYP ||
2929 s.kind == VAR ||
2930 (s.kind == MTH && !s.isConstructor() &&
2931 !s.type.getReturnType().hasTag(VOID)) ||
2932 (s.kind == MTH && s.isConstructor()))
2933 return true;
2934 }
2935 else if (target == names.TYPE_PARAMETER)
2936 { if (s.kind == TYP && s.type.hasTag(TYPEVAR))
2937 return true;
2938 }
2939 else
2940 return true; // recovery
2941 }
2942 return false;
2943 }
2946 Attribute.Array getAttributeTargetAttribute(Symbol s) {
2947 Attribute.Compound atTarget =
2948 s.attribute(syms.annotationTargetType.tsym);
2949 if (atTarget == null) return null; // ok, is applicable
2950 Attribute atValue = atTarget.member(names.value);
2951 if (!(atValue instanceof Attribute.Array)) return null; // error recovery
2952 return (Attribute.Array) atValue;
2953 }
2955 private final Name[] dfltTargetMeta;
2956 private Name[] defaultTargetMetaInfo(JCAnnotation a, Symbol s) {
2957 return dfltTargetMeta;
2958 }
2960 /** Check an annotation value.
2961 *
2962 * @param a The annotation tree to check
2963 * @return true if this annotation tree is valid, otherwise false
2964 */
2965 public boolean validateAnnotationDeferErrors(JCAnnotation a) {
2966 boolean res = false;
2967 final Log.DiagnosticHandler diagHandler = new Log.DiscardDiagnosticHandler(log);
2968 try {
2969 res = validateAnnotation(a);
2970 } finally {
2971 log.popDiagnosticHandler(diagHandler);
2972 }
2973 return res;
2974 }
2976 private boolean validateAnnotation(JCAnnotation a) {
2977 boolean isValid = true;
2978 // collect an inventory of the annotation elements
2979 Set<MethodSymbol> members = new LinkedHashSet<MethodSymbol>();
2980 for (Scope.Entry e = a.annotationType.type.tsym.members().elems;
2981 e != null;
2982 e = e.sibling)
2983 if (e.sym.kind == MTH)
2984 members.add((MethodSymbol) e.sym);
2986 // remove the ones that are assigned values
2987 for (JCTree arg : a.args) {
2988 if (!arg.hasTag(ASSIGN)) continue; // recovery
2989 JCAssign assign = (JCAssign) arg;
2990 Symbol m = TreeInfo.symbol(assign.lhs);
2991 if (m == null || m.type.isErroneous()) continue;
2992 if (!members.remove(m)) {
2993 isValid = false;
2994 log.error(assign.lhs.pos(), "duplicate.annotation.member.value",
2995 m.name, a.type);
2996 }
2997 }
2999 // all the remaining ones better have default values
3000 List<Name> missingDefaults = List.nil();
3001 for (MethodSymbol m : members) {
3002 if (m.defaultValue == null && !m.type.isErroneous()) {
3003 missingDefaults = missingDefaults.append(m.name);
3004 }
3005 }
3006 missingDefaults = missingDefaults.reverse();
3007 if (missingDefaults.nonEmpty()) {
3008 isValid = false;
3009 String key = (missingDefaults.size() > 1)
3010 ? "annotation.missing.default.value.1"
3011 : "annotation.missing.default.value";
3012 log.error(a.pos(), key, a.type, missingDefaults);
3013 }
3015 // special case: java.lang.annotation.Target must not have
3016 // repeated values in its value member
3017 if (a.annotationType.type.tsym != syms.annotationTargetType.tsym ||
3018 a.args.tail == null)
3019 return isValid;
3021 if (!a.args.head.hasTag(ASSIGN)) return false; // error recovery
3022 JCAssign assign = (JCAssign) a.args.head;
3023 Symbol m = TreeInfo.symbol(assign.lhs);
3024 if (m.name != names.value) return false;
3025 JCTree rhs = assign.rhs;
3026 if (!rhs.hasTag(NEWARRAY)) return false;
3027 JCNewArray na = (JCNewArray) rhs;
3028 Set<Symbol> targets = new HashSet<Symbol>();
3029 for (JCTree elem : na.elems) {
3030 if (!targets.add(TreeInfo.symbol(elem))) {
3031 isValid = false;
3032 log.error(elem.pos(), "repeated.annotation.target");
3033 }
3034 }
3035 return isValid;
3036 }
3038 void checkDeprecatedAnnotation(DiagnosticPosition pos, Symbol s) {
3039 if (allowAnnotations &&
3040 lint.isEnabled(LintCategory.DEP_ANN) &&
3041 (s.flags() & DEPRECATED) != 0 &&
3042 !syms.deprecatedType.isErroneous() &&
3043 s.attribute(syms.deprecatedType.tsym) == null) {
3044 log.warning(LintCategory.DEP_ANN,
3045 pos, "missing.deprecated.annotation");
3046 }
3047 }
3049 void checkDeprecated(final DiagnosticPosition pos, final Symbol other, final Symbol s) {
3050 if ((s.flags() & DEPRECATED) != 0 &&
3051 (other.flags() & DEPRECATED) == 0 &&
3052 s.outermostClass() != other.outermostClass()) {
3053 deferredLintHandler.report(new DeferredLintHandler.LintLogger() {
3054 @Override
3055 public void report() {
3056 warnDeprecated(pos, s);
3057 }
3058 });
3059 }
3060 }
3062 void checkSunAPI(final DiagnosticPosition pos, final Symbol s) {
3063 if ((s.flags() & PROPRIETARY) != 0) {
3064 deferredLintHandler.report(new DeferredLintHandler.LintLogger() {
3065 public void report() {
3066 if (enableSunApiLintControl)
3067 warnSunApi(pos, "sun.proprietary", s);
3068 else
3069 log.mandatoryWarning(pos, "sun.proprietary", s);
3070 }
3071 });
3072 }
3073 }
3075 void checkProfile(final DiagnosticPosition pos, final Symbol s) {
3076 if (profile != Profile.DEFAULT && (s.flags() & NOT_IN_PROFILE) != 0) {
3077 log.error(pos, "not.in.profile", s, profile);
3078 }
3079 }
3081 /* *************************************************************************
3082 * Check for recursive annotation elements.
3083 **************************************************************************/
3085 /** Check for cycles in the graph of annotation elements.
3086 */
3087 void checkNonCyclicElements(JCClassDecl tree) {
3088 if ((tree.sym.flags_field & ANNOTATION) == 0) return;
3089 Assert.check((tree.sym.flags_field & LOCKED) == 0);
3090 try {
3091 tree.sym.flags_field |= LOCKED;
3092 for (JCTree def : tree.defs) {
3093 if (!def.hasTag(METHODDEF)) continue;
3094 JCMethodDecl meth = (JCMethodDecl)def;
3095 checkAnnotationResType(meth.pos(), meth.restype.type);
3096 }
3097 } finally {
3098 tree.sym.flags_field &= ~LOCKED;
3099 tree.sym.flags_field |= ACYCLIC_ANN;
3100 }
3101 }
3103 void checkNonCyclicElementsInternal(DiagnosticPosition pos, TypeSymbol tsym) {
3104 if ((tsym.flags_field & ACYCLIC_ANN) != 0)
3105 return;
3106 if ((tsym.flags_field & LOCKED) != 0) {
3107 log.error(pos, "cyclic.annotation.element");
3108 return;
3109 }
3110 try {
3111 tsym.flags_field |= LOCKED;
3112 for (Scope.Entry e = tsym.members().elems; e != null; e = e.sibling) {
3113 Symbol s = e.sym;
3114 if (s.kind != Kinds.MTH)
3115 continue;
3116 checkAnnotationResType(pos, ((MethodSymbol)s).type.getReturnType());
3117 }
3118 } finally {
3119 tsym.flags_field &= ~LOCKED;
3120 tsym.flags_field |= ACYCLIC_ANN;
3121 }
3122 }
3124 void checkAnnotationResType(DiagnosticPosition pos, Type type) {
3125 switch (type.getTag()) {
3126 case CLASS:
3127 if ((type.tsym.flags() & ANNOTATION) != 0)
3128 checkNonCyclicElementsInternal(pos, type.tsym);
3129 break;
3130 case ARRAY:
3131 checkAnnotationResType(pos, types.elemtype(type));
3132 break;
3133 default:
3134 break; // int etc
3135 }
3136 }
3138 /* *************************************************************************
3139 * Check for cycles in the constructor call graph.
3140 **************************************************************************/
3142 /** Check for cycles in the graph of constructors calling other
3143 * constructors.
3144 */
3145 void checkCyclicConstructors(JCClassDecl tree) {
3146 Map<Symbol,Symbol> callMap = new HashMap<Symbol, Symbol>();
3148 // enter each constructor this-call into the map
3149 for (List<JCTree> l = tree.defs; l.nonEmpty(); l = l.tail) {
3150 JCMethodInvocation app = TreeInfo.firstConstructorCall(l.head);
3151 if (app == null) continue;
3152 JCMethodDecl meth = (JCMethodDecl) l.head;
3153 if (TreeInfo.name(app.meth) == names._this) {
3154 callMap.put(meth.sym, TreeInfo.symbol(app.meth));
3155 } else {
3156 meth.sym.flags_field |= ACYCLIC;
3157 }
3158 }
3160 // Check for cycles in the map
3161 Symbol[] ctors = new Symbol[0];
3162 ctors = callMap.keySet().toArray(ctors);
3163 for (Symbol caller : ctors) {
3164 checkCyclicConstructor(tree, caller, callMap);
3165 }
3166 }
3168 /** Look in the map to see if the given constructor is part of a
3169 * call cycle.
3170 */
3171 private void checkCyclicConstructor(JCClassDecl tree, Symbol ctor,
3172 Map<Symbol,Symbol> callMap) {
3173 if (ctor != null && (ctor.flags_field & ACYCLIC) == 0) {
3174 if ((ctor.flags_field & LOCKED) != 0) {
3175 log.error(TreeInfo.diagnosticPositionFor(ctor, tree),
3176 "recursive.ctor.invocation");
3177 } else {
3178 ctor.flags_field |= LOCKED;
3179 checkCyclicConstructor(tree, callMap.remove(ctor), callMap);
3180 ctor.flags_field &= ~LOCKED;
3181 }
3182 ctor.flags_field |= ACYCLIC;
3183 }
3184 }
3186 /* *************************************************************************
3187 * Miscellaneous
3188 **************************************************************************/
3190 /**
3191 * Return the opcode of the operator but emit an error if it is an
3192 * error.
3193 * @param pos position for error reporting.
3194 * @param operator an operator
3195 * @param tag a tree tag
3196 * @param left type of left hand side
3197 * @param right type of right hand side
3198 */
3199 int checkOperator(DiagnosticPosition pos,
3200 OperatorSymbol operator,
3201 JCTree.Tag tag,
3202 Type left,
3203 Type right) {
3204 if (operator.opcode == ByteCodes.error) {
3205 log.error(pos,
3206 "operator.cant.be.applied.1",
3207 treeinfo.operatorName(tag),
3208 left, right);
3209 }
3210 return operator.opcode;
3211 }
3214 /**
3215 * Check for division by integer constant zero
3216 * @param pos Position for error reporting.
3217 * @param operator The operator for the expression
3218 * @param operand The right hand operand for the expression
3219 */
3220 void checkDivZero(DiagnosticPosition pos, Symbol operator, Type operand) {
3221 if (operand.constValue() != null
3222 && lint.isEnabled(LintCategory.DIVZERO)
3223 && (operand.getTag().isSubRangeOf(LONG))
3224 && ((Number) (operand.constValue())).longValue() == 0) {
3225 int opc = ((OperatorSymbol)operator).opcode;
3226 if (opc == ByteCodes.idiv || opc == ByteCodes.imod
3227 || opc == ByteCodes.ldiv || opc == ByteCodes.lmod) {
3228 log.warning(LintCategory.DIVZERO, pos, "div.zero");
3229 }
3230 }
3231 }
3233 /**
3234 * Check for empty statements after if
3235 */
3236 void checkEmptyIf(JCIf tree) {
3237 if (tree.thenpart.hasTag(SKIP) && tree.elsepart == null &&
3238 lint.isEnabled(LintCategory.EMPTY))
3239 log.warning(LintCategory.EMPTY, tree.thenpart.pos(), "empty.if");
3240 }
3242 /** Check that symbol is unique in given scope.
3243 * @param pos Position for error reporting.
3244 * @param sym The symbol.
3245 * @param s The scope.
3246 */
3247 boolean checkUnique(DiagnosticPosition pos, Symbol sym, Scope s) {
3248 if (sym.type.isErroneous())
3249 return true;
3250 if (sym.owner.name == names.any) return false;
3251 for (Scope.Entry e = s.lookup(sym.name); e.scope == s; e = e.next()) {
3252 if (sym != e.sym &&
3253 (e.sym.flags() & CLASH) == 0 &&
3254 sym.kind == e.sym.kind &&
3255 sym.name != names.error &&
3256 (sym.kind != MTH || types.hasSameArgs(types.erasure(sym.type), types.erasure(e.sym.type)))) {
3257 if ((sym.flags() & VARARGS) != (e.sym.flags() & VARARGS)) {
3258 varargsDuplicateError(pos, sym, e.sym);
3259 return true;
3260 } else if (sym.kind == MTH && !types.hasSameArgs(sym.type, e.sym.type, false)) {
3261 duplicateErasureError(pos, sym, e.sym);
3262 sym.flags_field |= CLASH;
3263 return true;
3264 } else {
3265 duplicateError(pos, e.sym);
3266 return false;
3267 }
3268 }
3269 }
3270 return true;
3271 }
3273 /** Report duplicate declaration error.
3274 */
3275 void duplicateErasureError(DiagnosticPosition pos, Symbol sym1, Symbol sym2) {
3276 if (!sym1.type.isErroneous() && !sym2.type.isErroneous()) {
3277 log.error(pos, "name.clash.same.erasure", sym1, sym2);
3278 }
3279 }
3281 /** Check that single-type import is not already imported or top-level defined,
3282 * but make an exception for two single-type imports which denote the same type.
3283 * @param pos Position for error reporting.
3284 * @param sym The symbol.
3285 * @param s The scope
3286 */
3287 boolean checkUniqueImport(DiagnosticPosition pos, Symbol sym, Scope s) {
3288 return checkUniqueImport(pos, sym, s, false);
3289 }
3291 /** Check that static single-type import is not already imported or top-level defined,
3292 * but make an exception for two single-type imports which denote the same type.
3293 * @param pos Position for error reporting.
3294 * @param sym The symbol.
3295 * @param s The scope
3296 */
3297 boolean checkUniqueStaticImport(DiagnosticPosition pos, Symbol sym, Scope s) {
3298 return checkUniqueImport(pos, sym, s, true);
3299 }
3301 /** Check that single-type import is not already imported or top-level defined,
3302 * but make an exception for two single-type imports which denote the same type.
3303 * @param pos Position for error reporting.
3304 * @param sym The symbol.
3305 * @param s The scope.
3306 * @param staticImport Whether or not this was a static import
3307 */
3308 private boolean checkUniqueImport(DiagnosticPosition pos, Symbol sym, Scope s, boolean staticImport) {
3309 for (Scope.Entry e = s.lookup(sym.name); e.scope != null; e = e.next()) {
3310 // is encountered class entered via a class declaration?
3311 boolean isClassDecl = e.scope == s;
3312 if ((isClassDecl || sym != e.sym) &&
3313 sym.kind == e.sym.kind &&
3314 sym.name != names.error) {
3315 if (!e.sym.type.isErroneous()) {
3316 String what = e.sym.toString();
3317 if (!isClassDecl) {
3318 if (staticImport)
3319 log.error(pos, "already.defined.static.single.import", what);
3320 else
3321 log.error(pos, "already.defined.single.import", what);
3322 }
3323 else if (sym != e.sym)
3324 log.error(pos, "already.defined.this.unit", what);
3325 }
3326 return false;
3327 }
3328 }
3329 return true;
3330 }
3332 /** Check that a qualified name is in canonical form (for import decls).
3333 */
3334 public void checkCanonical(JCTree tree) {
3335 if (!isCanonical(tree))
3336 log.error(tree.pos(), "import.requires.canonical",
3337 TreeInfo.symbol(tree));
3338 }
3339 // where
3340 private boolean isCanonical(JCTree tree) {
3341 while (tree.hasTag(SELECT)) {
3342 JCFieldAccess s = (JCFieldAccess) tree;
3343 if (s.sym.owner != TreeInfo.symbol(s.selected))
3344 return false;
3345 tree = s.selected;
3346 }
3347 return true;
3348 }
3350 /** Check that an auxiliary class is not accessed from any other file than its own.
3351 */
3352 void checkForBadAuxiliaryClassAccess(DiagnosticPosition pos, Env<AttrContext> env, ClassSymbol c) {
3353 if (lint.isEnabled(Lint.LintCategory.AUXILIARYCLASS) &&
3354 (c.flags() & AUXILIARY) != 0 &&
3355 rs.isAccessible(env, c) &&
3356 !fileManager.isSameFile(c.sourcefile, env.toplevel.sourcefile))
3357 {
3358 log.warning(pos, "auxiliary.class.accessed.from.outside.of.its.source.file",
3359 c, c.sourcefile);
3360 }
3361 }
3363 private class ConversionWarner extends Warner {
3364 final String uncheckedKey;
3365 final Type found;
3366 final Type expected;
3367 public ConversionWarner(DiagnosticPosition pos, String uncheckedKey, Type found, Type expected) {
3368 super(pos);
3369 this.uncheckedKey = uncheckedKey;
3370 this.found = found;
3371 this.expected = expected;
3372 }
3374 @Override
3375 public void warn(LintCategory lint) {
3376 boolean warned = this.warned;
3377 super.warn(lint);
3378 if (warned) return; // suppress redundant diagnostics
3379 switch (lint) {
3380 case UNCHECKED:
3381 Check.this.warnUnchecked(pos(), "prob.found.req", diags.fragment(uncheckedKey), found, expected);
3382 break;
3383 case VARARGS:
3384 if (method != null &&
3385 method.attribute(syms.trustMeType.tsym) != null &&
3386 isTrustMeAllowedOnMethod(method) &&
3387 !types.isReifiable(method.type.getParameterTypes().last())) {
3388 Check.this.warnUnsafeVararg(pos(), "varargs.unsafe.use.varargs.param", method.params.last());
3389 }
3390 break;
3391 default:
3392 throw new AssertionError("Unexpected lint: " + lint);
3393 }
3394 }
3395 }
3397 public Warner castWarner(DiagnosticPosition pos, Type found, Type expected) {
3398 return new ConversionWarner(pos, "unchecked.cast.to.type", found, expected);
3399 }
3401 public Warner convertWarner(DiagnosticPosition pos, Type found, Type expected) {
3402 return new ConversionWarner(pos, "unchecked.assign", found, expected);
3403 }
3404 }