1 /*
2 * Copyright (c) 1999, 2014, 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 */
25
26 package com.sun.tools.javac.comp;
27
28 import java.util.*;
29
30 import javax.tools.JavaFileManager;
31
32 import com.sun.tools.javac.code.*;
33 import com.sun.tools.javac.code.Attribute.Compound;
34 import com.sun.tools.javac.jvm.*;
35 import com.sun.tools.javac.tree.*;
36 import com.sun.tools.javac.util.*;
37 import com.sun.tools.javac.util.JCDiagnostic.DiagnosticPosition;
38 import com.sun.tools.javac.util.List;
39
40 import com.sun.tools.javac.code.Lint;
41 import com.sun.tools.javac.code.Lint.LintCategory;
42 import com.sun.tools.javac.code.Type.*;
43 import com.sun.tools.javac.code.Symbol.*;
44 import com.sun.tools.javac.comp.DeferredAttr.DeferredAttrContext;
45 import com.sun.tools.javac.comp.Infer.InferenceContext;
46 import com.sun.tools.javac.comp.Infer.FreeTypeListener;
47 import com.sun.tools.javac.tree.JCTree.*;
48 import com.sun.tools.javac.tree.JCTree.JCPolyExpression.*;
49
50 import static com.sun.tools.javac.code.Flags.*;
51 import static com.sun.tools.javac.code.Flags.ANNOTATION;
52 import static com.sun.tools.javac.code.Flags.SYNCHRONIZED;
53 import static com.sun.tools.javac.code.Kinds.*;
54 import static com.sun.tools.javac.code.TypeTag.*;
55 import static com.sun.tools.javac.code.TypeTag.WILDCARD;
56
57 import static com.sun.tools.javac.tree.JCTree.Tag.*;
58
59 /** Type checking helper class for the attribution phase.
60 *
61 * <p><b>This is NOT part of any supported API.
62 * If you write code that depends on this, you do so at your own risk.
63 * This code and its internal interfaces are subject to change or
64 * deletion without notice.</b>
65 */
66 public class Check {
67 protected static final Context.Key<Check> checkKey =
68 new Context.Key<Check>();
69
70 private final Names names;
71 private final Log log;
72 private final Resolve rs;
73 private final Symtab syms;
74 private final Enter enter;
75 private final DeferredAttr deferredAttr;
76 private final Infer infer;
77 private final Types types;
78 private final JCDiagnostic.Factory diags;
79 private boolean warnOnSyntheticConflicts;
80 private boolean suppressAbortOnBadClassFile;
81 private boolean enableSunApiLintControl;
82 private final TreeInfo treeinfo;
83 private final JavaFileManager fileManager;
84 private final Profile profile;
85 private final boolean warnOnAccessToSensitiveMembers;
86
87 // The set of lint options currently in effect. It is initialized
88 // from the context, and then is set/reset as needed by Attr as it
89 // visits all the various parts of the trees during attribution.
90 private Lint lint;
91
92 // The method being analyzed in Attr - it is set/reset as needed by
93 // Attr as it visits new method declarations.
94 private MethodSymbol method;
95
96 public static Check instance(Context context) {
97 Check instance = context.get(checkKey);
98 if (instance == null)
99 instance = new Check(context);
100 return instance;
101 }
102
103 protected Check(Context context) {
104 context.put(checkKey, this);
105
106 names = Names.instance(context);
107 dfltTargetMeta = new Name[] { names.PACKAGE, names.TYPE,
108 names.FIELD, names.METHOD, names.CONSTRUCTOR,
109 names.ANNOTATION_TYPE, names.LOCAL_VARIABLE, names.PARAMETER};
110 log = Log.instance(context);
111 rs = Resolve.instance(context);
112 syms = Symtab.instance(context);
113 enter = Enter.instance(context);
114 deferredAttr = DeferredAttr.instance(context);
115 infer = Infer.instance(context);
116 types = Types.instance(context);
117 diags = JCDiagnostic.Factory.instance(context);
118 Options options = Options.instance(context);
119 lint = Lint.instance(context);
120 treeinfo = TreeInfo.instance(context);
121 fileManager = context.get(JavaFileManager.class);
122
123 Source source = Source.instance(context);
124 allowGenerics = source.allowGenerics();
125 allowVarargs = source.allowVarargs();
126 allowAnnotations = source.allowAnnotations();
127 allowCovariantReturns = source.allowCovariantReturns();
128 allowSimplifiedVarargs = source.allowSimplifiedVarargs();
129 allowDefaultMethods = source.allowDefaultMethods();
130 allowStrictMethodClashCheck = source.allowStrictMethodClashCheck();
131 complexInference = options.isSet("complexinference");
132 warnOnSyntheticConflicts = options.isSet("warnOnSyntheticConflicts");
133 suppressAbortOnBadClassFile = options.isSet("suppressAbortOnBadClassFile");
134 enableSunApiLintControl = options.isSet("enableSunApiLintControl");
135 warnOnAccessToSensitiveMembers = options.isSet("warnOnAccessToSensitiveMembers");
136
137 Target target = Target.instance(context);
138 syntheticNameChar = target.syntheticNameChar();
139
140 profile = Profile.instance(context);
141
142 boolean verboseDeprecated = lint.isEnabled(LintCategory.DEPRECATION);
143 boolean verboseUnchecked = lint.isEnabled(LintCategory.UNCHECKED);
144 boolean verboseSunApi = lint.isEnabled(LintCategory.SUNAPI);
145 boolean enforceMandatoryWarnings = source.enforceMandatoryWarnings();
146
147 deprecationHandler = new MandatoryWarningHandler(log, verboseDeprecated,
148 enforceMandatoryWarnings, "deprecated", LintCategory.DEPRECATION);
149 uncheckedHandler = new MandatoryWarningHandler(log, verboseUnchecked,
150 enforceMandatoryWarnings, "unchecked", LintCategory.UNCHECKED);
151 sunApiHandler = new MandatoryWarningHandler(log, verboseSunApi,
152 enforceMandatoryWarnings, "sunapi", null);
153
154 deferredLintHandler = DeferredLintHandler.instance(context);
155 }
156
157 /** Switch: generics enabled?
158 */
159 boolean allowGenerics;
160
161 /** Switch: varargs enabled?
162 */
163 boolean allowVarargs;
164
165 /** Switch: annotations enabled?
166 */
167 boolean allowAnnotations;
168
169 /** Switch: covariant returns enabled?
170 */
171 boolean allowCovariantReturns;
172
173 /** Switch: simplified varargs enabled?
174 */
175 boolean allowSimplifiedVarargs;
176
177 /** Switch: default methods enabled?
178 */
179 boolean allowDefaultMethods;
180
181 /** Switch: should unrelated return types trigger a method clash?
182 */
183 boolean allowStrictMethodClashCheck;
184
185 /** Switch: -complexinference option set?
186 */
187 boolean complexInference;
188
189 /** Character for synthetic names
190 */
191 char syntheticNameChar;
192
193 /** A table mapping flat names of all compiled classes in this run to their
194 * symbols; maintained from outside.
195 */
196 public Map<Name,ClassSymbol> compiled = new HashMap<Name, ClassSymbol>();
197
198 /** A handler for messages about deprecated usage.
199 */
200 private MandatoryWarningHandler deprecationHandler;
201
202 /** A handler for messages about unchecked or unsafe usage.
203 */
204 private MandatoryWarningHandler uncheckedHandler;
205
206 /** A handler for messages about using proprietary API.
207 */
208 private MandatoryWarningHandler sunApiHandler;
209
210 /** A handler for deferred lint warnings.
211 */
212 private DeferredLintHandler deferredLintHandler;
213
214 /* *************************************************************************
215 * Errors and Warnings
216 **************************************************************************/
217
218 Lint setLint(Lint newLint) {
219 Lint prev = lint;
220 lint = newLint;
221 return prev;
222 }
223
224 MethodSymbol setMethod(MethodSymbol newMethod) {
225 MethodSymbol prev = method;
226 method = newMethod;
227 return prev;
228 }
229
230 /** Warn about deprecated symbol.
231 * @param pos Position to be used for error reporting.
232 * @param sym The deprecated symbol.
233 */
234 void warnDeprecated(DiagnosticPosition pos, Symbol sym) {
235 if (!lint.isSuppressed(LintCategory.DEPRECATION))
236 deprecationHandler.report(pos, "has.been.deprecated", sym, sym.location());
237 }
238
239 /** Warn about unchecked operation.
240 * @param pos Position to be used for error reporting.
241 * @param msg A string describing the problem.
242 */
243 public void warnUnchecked(DiagnosticPosition pos, String msg, Object... args) {
244 if (!lint.isSuppressed(LintCategory.UNCHECKED))
245 uncheckedHandler.report(pos, msg, args);
246 }
247
248 /** Warn about unsafe vararg method decl.
249 * @param pos Position to be used for error reporting.
250 */
251 void warnUnsafeVararg(DiagnosticPosition pos, String key, Object... args) {
252 if (lint.isEnabled(LintCategory.VARARGS) && allowSimplifiedVarargs)
253 log.warning(LintCategory.VARARGS, pos, key, args);
254 }
255
256 /** Warn about using proprietary API.
257 * @param pos Position to be used for error reporting.
258 * @param msg A string describing the problem.
259 */
260 public void warnSunApi(DiagnosticPosition pos, String msg, Object... args) {
261 if (!lint.isSuppressed(LintCategory.SUNAPI))
262 sunApiHandler.report(pos, msg, args);
263 }
264
265 public void warnStatic(DiagnosticPosition pos, String msg, Object... args) {
266 if (lint.isEnabled(LintCategory.STATIC))
267 log.warning(LintCategory.STATIC, pos, msg, args);
268 }
269
270 /**
271 * Report any deferred diagnostics.
272 */
273 public void reportDeferredDiagnostics() {
274 deprecationHandler.reportDeferredDiagnostic();
275 uncheckedHandler.reportDeferredDiagnostic();
276 sunApiHandler.reportDeferredDiagnostic();
277 }
278
279
280 /** Report a failure to complete a class.
281 * @param pos Position to be used for error reporting.
282 * @param ex The failure to report.
283 */
284 public Type completionError(DiagnosticPosition pos, CompletionFailure ex) {
285 log.error(JCDiagnostic.DiagnosticFlag.NON_DEFERRABLE, pos, "cant.access", ex.sym, ex.getDetailValue());
286 if (ex instanceof ClassReader.BadClassFile
287 && !suppressAbortOnBadClassFile) throw new Abort();
288 else return syms.errType;
289 }
290
291 /** Report an error that wrong type tag was found.
292 * @param pos Position to be used for error reporting.
293 * @param required An internationalized string describing the type tag
294 * required.
295 * @param found The type that was found.
296 */
297 Type typeTagError(DiagnosticPosition pos, Object required, Object found) {
298 // this error used to be raised by the parser,
299 // but has been delayed to this point:
300 if (found instanceof Type && ((Type)found).hasTag(VOID)) {
301 log.error(pos, "illegal.start.of.type");
302 return syms.errType;
303 }
304 log.error(pos, "type.found.req", found, required);
305 return types.createErrorType(found instanceof Type ? (Type)found : syms.errType);
306 }
307
308 /** Report an error that symbol cannot be referenced before super
309 * has been called.
310 * @param pos Position to be used for error reporting.
311 * @param sym The referenced symbol.
312 */
313 void earlyRefError(DiagnosticPosition pos, Symbol sym) {
314 log.error(pos, "cant.ref.before.ctor.called", sym);
315 }
316
317 /** Report duplicate declaration error.
318 */
319 void duplicateError(DiagnosticPosition pos, Symbol sym) {
320 if (!sym.type.isErroneous()) {
321 Symbol location = sym.location();
322 if (location.kind == MTH &&
323 ((MethodSymbol)location).isStaticOrInstanceInit()) {
324 log.error(pos, "already.defined.in.clinit", kindName(sym), sym,
325 kindName(sym.location()), kindName(sym.location().enclClass()),
326 sym.location().enclClass());
327 } else {
328 log.error(pos, "already.defined", kindName(sym), sym,
329 kindName(sym.location()), sym.location());
330 }
331 }
332 }
333
334 /** Report array/varargs duplicate declaration
335 */
336 void varargsDuplicateError(DiagnosticPosition pos, Symbol sym1, Symbol sym2) {
337 if (!sym1.type.isErroneous() && !sym2.type.isErroneous()) {
338 log.error(pos, "array.and.varargs", sym1, sym2, sym2.location());
339 }
340 }
341
342 /* ************************************************************************
343 * duplicate declaration checking
344 *************************************************************************/
345
346 /** Check that variable does not hide variable with same name in
347 * immediately enclosing local scope.
348 * @param pos Position for error reporting.
349 * @param v The symbol.
350 * @param s The scope.
351 */
352 void checkTransparentVar(DiagnosticPosition pos, VarSymbol v, Scope s) {
353 if (s.next != null) {
354 for (Scope.Entry e = s.next.lookup(v.name);
355 e.scope != null && e.sym.owner == v.owner;
356 e = e.next()) {
357 if (e.sym.kind == VAR &&
358 (e.sym.owner.kind & (VAR | MTH)) != 0 &&
359 v.name != names.error) {
360 duplicateError(pos, e.sym);
361 return;
362 }
363 }
364 }
365 }
366
367 /** Check that a class or interface does not hide a class or
368 * interface with same name in immediately enclosing local scope.
369 * @param pos Position for error reporting.
370 * @param c The symbol.
371 * @param s The scope.
372 */
373 void checkTransparentClass(DiagnosticPosition pos, ClassSymbol c, Scope s) {
374 if (s.next != null) {
375 for (Scope.Entry e = s.next.lookup(c.name);
376 e.scope != null && e.sym.owner == c.owner;
377 e = e.next()) {
378 if (e.sym.kind == TYP && !e.sym.type.hasTag(TYPEVAR) &&
379 (e.sym.owner.kind & (VAR | MTH)) != 0 &&
380 c.name != names.error) {
381 duplicateError(pos, e.sym);
382 return;
383 }
384 }
385 }
386 }
387
388 /** Check that class does not have the same name as one of
389 * its enclosing classes, or as a class defined in its enclosing scope.
390 * return true if class is unique in its enclosing scope.
391 * @param pos Position for error reporting.
392 * @param name The class name.
393 * @param s The enclosing scope.
394 */
395 boolean checkUniqueClassName(DiagnosticPosition pos, Name name, Scope s) {
396 for (Scope.Entry e = s.lookup(name); e.scope == s; e = e.next()) {
397 if (e.sym.kind == TYP && e.sym.name != names.error) {
398 duplicateError(pos, e.sym);
399 return false;
400 }
401 }
402 for (Symbol sym = s.owner; sym != null; sym = sym.owner) {
403 if (sym.kind == TYP && sym.name == name && sym.name != names.error) {
404 duplicateError(pos, sym);
405 return true;
406 }
407 }
408 return true;
409 }
410
411 /* *************************************************************************
412 * Class name generation
413 **************************************************************************/
414
415 /** Return name of local class.
416 * This is of the form {@code <enclClass> $ n <classname> }
417 * where
418 * enclClass is the flat name of the enclosing class,
419 * classname is the simple name of the local class
420 */
421 Name localClassName(ClassSymbol c) {
422 for (int i=1; ; i++) {
423 Name flatname = names.
424 fromString("" + c.owner.enclClass().flatname +
425 syntheticNameChar + i +
426 c.name);
427 if (compiled.get(flatname) == null) return flatname;
428 }
429 }
430
431 /* *************************************************************************
432 * Type Checking
433 **************************************************************************/
434
435 /**
436 * A check context is an object that can be used to perform compatibility
437 * checks - depending on the check context, meaning of 'compatibility' might
438 * vary significantly.
439 */
440 public interface CheckContext {
441 /**
442 * Is type 'found' compatible with type 'req' in given context
443 */
444 boolean compatible(Type found, Type req, Warner warn);
445 /**
446 * Report a check error
447 */
448 void report(DiagnosticPosition pos, JCDiagnostic details);
449 /**
450 * Obtain a warner for this check context
451 */
452 public Warner checkWarner(DiagnosticPosition pos, Type found, Type req);
453
454 public Infer.InferenceContext inferenceContext();
455
456 public DeferredAttr.DeferredAttrContext deferredAttrContext();
457 }
458
459 /**
460 * This class represent a check context that is nested within another check
461 * context - useful to check sub-expressions. The default behavior simply
462 * redirects all method calls to the enclosing check context leveraging
463 * the forwarding pattern.
464 */
465 static class NestedCheckContext implements CheckContext {
466 CheckContext enclosingContext;
467
468 NestedCheckContext(CheckContext enclosingContext) {
469 this.enclosingContext = enclosingContext;
470 }
471
472 public boolean compatible(Type found, Type req, Warner warn) {
473 return enclosingContext.compatible(found, req, warn);
474 }
475
476 public void report(DiagnosticPosition pos, JCDiagnostic details) {
477 enclosingContext.report(pos, details);
478 }
479
480 public Warner checkWarner(DiagnosticPosition pos, Type found, Type req) {
481 return enclosingContext.checkWarner(pos, found, req);
482 }
483
484 public Infer.InferenceContext inferenceContext() {
485 return enclosingContext.inferenceContext();
486 }
487
488 public DeferredAttrContext deferredAttrContext() {
489 return enclosingContext.deferredAttrContext();
490 }
491 }
492
493 /**
494 * Check context to be used when evaluating assignment/return statements
495 */
496 CheckContext basicHandler = new CheckContext() {
497 public void report(DiagnosticPosition pos, JCDiagnostic details) {
498 log.error(pos, "prob.found.req", details);
499 }
500 public boolean compatible(Type found, Type req, Warner warn) {
501 return types.isAssignable(found, req, warn);
502 }
503
504 public Warner checkWarner(DiagnosticPosition pos, Type found, Type req) {
505 return convertWarner(pos, found, req);
506 }
507
508 public InferenceContext inferenceContext() {
509 return infer.emptyContext;
510 }
511
512 public DeferredAttrContext deferredAttrContext() {
513 return deferredAttr.emptyDeferredAttrContext;
514 }
515
516 @Override
517 public String toString() {
518 return "CheckContext: basicHandler";
519 }
520 };
521
522 /** Check that a given type is assignable to a given proto-type.
523 * If it is, return the type, otherwise return errType.
524 * @param pos Position to be used for error reporting.
525 * @param found The type that was found.
526 * @param req The type that was required.
527 */
528 Type checkType(DiagnosticPosition pos, Type found, Type req) {
529 return checkType(pos, found, req, basicHandler);
530 }
531
532 Type checkType(final DiagnosticPosition pos, final Type found, final Type req, final CheckContext checkContext) {
533 final Infer.InferenceContext inferenceContext = checkContext.inferenceContext();
534 if (inferenceContext.free(req) || inferenceContext.free(found)) {
535 inferenceContext.addFreeTypeListener(List.of(req, found), new FreeTypeListener() {
536 @Override
537 public void typesInferred(InferenceContext inferenceContext) {
538 checkType(pos, inferenceContext.asInstType(found), inferenceContext.asInstType(req), checkContext);
539 }
540 });
541 }
542 if (req.hasTag(ERROR))
543 return req;
544 if (req.hasTag(NONE))
545 return found;
546 if (checkContext.compatible(found, req, checkContext.checkWarner(pos, found, req))) {
547 return found;
548 } else {
549 if (found.isNumeric() && req.isNumeric()) {
550 checkContext.report(pos, diags.fragment("possible.loss.of.precision", found, req));
551 return types.createErrorType(found);
552 }
553 checkContext.report(pos, diags.fragment("inconvertible.types", found, req));
554 return types.createErrorType(found);
555 }
556 }
557
558 /** Check that a given type can be cast to a given target type.
559 * Return the result of the cast.
560 * @param pos Position to be used for error reporting.
561 * @param found The type that is being cast.
562 * @param req The target type of the cast.
563 */
564 Type checkCastable(DiagnosticPosition pos, Type found, Type req) {
565 return checkCastable(pos, found, req, basicHandler);
566 }
567 Type checkCastable(DiagnosticPosition pos, Type found, Type req, CheckContext checkContext) {
568 if (types.isCastable(found, req, castWarner(pos, found, req))) {
569 return req;
570 } else {
571 checkContext.report(pos, diags.fragment("inconvertible.types", found, req));
572 return types.createErrorType(found);
573 }
574 }
575
576 /** Check for redundant casts (i.e. where source type is a subtype of target type)
577 * The problem should only be reported for non-292 cast
578 */
579 public void checkRedundantCast(Env<AttrContext> env, final JCTypeCast tree) {
580 if (!tree.type.isErroneous()
581 && types.isSameType(tree.expr.type, tree.clazz.type)
582 && !(ignoreAnnotatedCasts && TreeInfo.containsTypeAnnotation(tree.clazz))
583 && !is292targetTypeCast(tree)) {
584 deferredLintHandler.report(new DeferredLintHandler.LintLogger() {
585 @Override
586 public void report() {
587 if (lint.isEnabled(Lint.LintCategory.CAST))
588 log.warning(Lint.LintCategory.CAST,
589 tree.pos(), "redundant.cast", tree.expr.type);
590 }
591 });
592 }
593 }
594 //where
595 private boolean is292targetTypeCast(JCTypeCast tree) {
596 boolean is292targetTypeCast = false;
597 JCExpression expr = TreeInfo.skipParens(tree.expr);
598 if (expr.hasTag(APPLY)) {
599 JCMethodInvocation apply = (JCMethodInvocation)expr;
600 Symbol sym = TreeInfo.symbol(apply.meth);
601 is292targetTypeCast = sym != null &&
602 sym.kind == MTH &&
603 (sym.flags() & HYPOTHETICAL) != 0;
604 }
605 return is292targetTypeCast;
606 }
607
608 private static final boolean ignoreAnnotatedCasts = true;
609
610 /** Check that a type is within some bounds.
611 *
612 * Used in TypeApply to verify that, e.g., X in {@code V<X>} is a valid
613 * type argument.
614 * @param a The type that should be bounded by bs.
615 * @param bound The bound.
616 */
617 private boolean checkExtends(Type a, Type bound) {
618 if (a.isUnbound()) {
619 return true;
620 } else if (!a.hasTag(WILDCARD)) {
621 a = types.cvarUpperBound(a);
622 return types.isSubtype(a, bound);
623 } else if (a.isExtendsBound()) {
624 return types.isCastable(bound, types.wildUpperBound(a), types.noWarnings);
625 } else if (a.isSuperBound()) {
626 return !types.notSoftSubtype(types.wildLowerBound(a), bound);
627 }
628 return true;
629 }
630
631 /** Check that type is different from 'void'.
632 * @param pos Position to be used for error reporting.
633 * @param t The type to be checked.
634 */
635 Type checkNonVoid(DiagnosticPosition pos, Type t) {
636 if (t.hasTag(VOID)) {
637 log.error(pos, "void.not.allowed.here");
638 return types.createErrorType(t);
639 } else {
640 return t;
641 }
642 }
643
644 Type checkClassOrArrayType(DiagnosticPosition pos, Type t) {
645 if (!t.hasTag(CLASS) && !t.hasTag(ARRAY) && !t.hasTag(ERROR)) {
646 return typeTagError(pos,
647 diags.fragment("type.req.class.array"),
648 asTypeParam(t));
649 } else {
650 return t;
651 }
652 }
653
654 /** Check that type is a class or interface type.
655 * @param pos Position to be used for error reporting.
656 * @param t The type to be checked.
657 */
658 Type checkClassType(DiagnosticPosition pos, Type t) {
659 if (!t.hasTag(CLASS) && !t.hasTag(ERROR)) {
660 return typeTagError(pos,
661 diags.fragment("type.req.class"),
662 asTypeParam(t));
663 } else {
664 return t;
665 }
666 }
667 //where
668 private Object asTypeParam(Type t) {
669 return (t.hasTag(TYPEVAR))
670 ? diags.fragment("type.parameter", t)
671 : t;
672 }
673
674 /** Check that type is a valid qualifier for a constructor reference expression
675 */
676 Type checkConstructorRefType(DiagnosticPosition pos, Type t) {
677 t = checkClassOrArrayType(pos, t);
678 if (t.hasTag(CLASS)) {
679 if ((t.tsym.flags() & (ABSTRACT | INTERFACE)) != 0) {
680 log.error(pos, "abstract.cant.be.instantiated", t.tsym);
681 t = types.createErrorType(t);
682 } else if ((t.tsym.flags() & ENUM) != 0) {
683 log.error(pos, "enum.cant.be.instantiated");
684 t = types.createErrorType(t);
685 } else {
686 t = checkClassType(pos, t, true);
687 }
688 } else if (t.hasTag(ARRAY)) {
689 if (!types.isReifiable(((ArrayType)t).elemtype)) {
690 log.error(pos, "generic.array.creation");
691 t = types.createErrorType(t);
692 }
693 }
694 return t;
695 }
696
697 /** Check that type is a class or interface type.
698 * @param pos Position to be used for error reporting.
699 * @param t The type to be checked.
700 * @param noBounds True if type bounds are illegal here.
701 */
702 Type checkClassType(DiagnosticPosition pos, Type t, boolean noBounds) {
703 t = checkClassType(pos, t);
704 if (noBounds && t.isParameterized()) {
705 List<Type> args = t.getTypeArguments();
706 while (args.nonEmpty()) {
707 if (args.head.hasTag(WILDCARD))
708 return typeTagError(pos,
709 diags.fragment("type.req.exact"),
710 args.head);
711 args = args.tail;
712 }
713 }
714 return t;
715 }
716
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 }
730
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 }
744
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.isReference() || t.hasTag(BOT))
751 return t;
752 else
753 return typeTagError(pos,
754 diags.fragment("type.req.ref"),
755 t);
756 }
757
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 }
775
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 }
803
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 }
842
843 Type checkMethod(final Type mtype,
844 final Symbol sym,
845 final Env<AttrContext> env,
846 final List<JCExpression> argtrees,
847 final List<Type> argtypes,
848 final boolean useVarargs,
849 InferenceContext inferenceContext) {
850 // System.out.println("call : " + env.tree);
851 // System.out.println("method : " + owntype);
852 // System.out.println("actuals: " + argtypes);
853 if (inferenceContext.free(mtype)) {
854 inferenceContext.addFreeTypeListener(List.of(mtype), new FreeTypeListener() {
855 public void typesInferred(InferenceContext inferenceContext) {
856 checkMethod(inferenceContext.asInstType(mtype), sym, env, argtrees, argtypes, useVarargs, inferenceContext);
857 }
858 });
859 return mtype;
860 }
861 Type owntype = mtype;
862 List<Type> formals = owntype.getParameterTypes();
863 List<Type> nonInferred = sym.type.getParameterTypes();
864 if (nonInferred.length() != formals.length()) nonInferred = formals;
865 Type last = useVarargs ? formals.last() : null;
866 if (sym.name == names.init && sym.owner == syms.enumSym) {
867 formals = formals.tail.tail;
868 nonInferred = nonInferred.tail.tail;
869 }
870 List<JCExpression> args = argtrees;
871 if (args != null) {
872 //this is null when type-checking a method reference
873 while (formals.head != last) {
874 JCTree arg = args.head;
875 Warner warn = convertWarner(arg.pos(), arg.type, nonInferred.head);
876 assertConvertible(arg, arg.type, formals.head, warn);
877 args = args.tail;
878 formals = formals.tail;
879 nonInferred = nonInferred.tail;
880 }
881 if (useVarargs) {
882 Type varArg = types.elemtype(last);
883 while (args.tail != null) {
884 JCTree arg = args.head;
885 Warner warn = convertWarner(arg.pos(), arg.type, varArg);
886 assertConvertible(arg, arg.type, varArg, warn);
887 args = args.tail;
888 }
889 } else if ((sym.flags() & (VARARGS | SIGNATURE_POLYMORPHIC)) == VARARGS &&
890 allowVarargs) {
891 // non-varargs call to varargs method
892 Type varParam = owntype.getParameterTypes().last();
893 Type lastArg = argtypes.last();
894 if (types.isSubtypeUnchecked(lastArg, types.elemtype(varParam)) &&
895 !types.isSameType(types.erasure(varParam), types.erasure(lastArg)))
896 log.warning(argtrees.last().pos(), "inexact.non-varargs.call",
897 types.elemtype(varParam), varParam);
898 }
899 }
900 if (useVarargs) {
901 Type argtype = owntype.getParameterTypes().last();
902 if (!types.isReifiable(argtype) &&
903 (!allowSimplifiedVarargs ||
904 sym.attribute(syms.trustMeType.tsym) == null ||
905 !isTrustMeAllowedOnMethod(sym))) {
906 warnUnchecked(env.tree.pos(),
907 "unchecked.generic.array.creation",
908 argtype);
909 }
910 if ((sym.baseSymbol().flags() & SIGNATURE_POLYMORPHIC) == 0) {
911 TreeInfo.setVarargsElement(env.tree, types.elemtype(argtype));
912 }
913 }
914 PolyKind pkind = (sym.type.hasTag(FORALL) &&
915 sym.type.getReturnType().containsAny(((ForAll)sym.type).tvars)) ?
916 PolyKind.POLY : PolyKind.STANDALONE;
917 TreeInfo.setPolyKind(env.tree, pkind);
918 return owntype;
919 }
920 //where
921 private void assertConvertible(JCTree tree, Type actual, Type formal, Warner warn) {
922 if (types.isConvertible(actual, formal, warn))
923 return;
924
925 if (formal.isCompound()
926 && types.isSubtype(actual, types.supertype(formal))
927 && types.isSubtypeUnchecked(actual, types.interfaces(formal), warn))
928 return;
929 }
930
931 /**
932 * Check that type 't' is a valid instantiation of a generic class
933 * (see JLS 4.5)
934 *
935 * @param t class type to be checked
936 * @return true if 't' is well-formed
937 */
938 public boolean checkValidGenericType(Type t) {
939 return firstIncompatibleTypeArg(t) == null;
940 }
941 //WHERE
942 private Type firstIncompatibleTypeArg(Type type) {
943 List<Type> formals = type.tsym.type.allparams();
944 List<Type> actuals = type.allparams();
945 List<Type> args = type.getTypeArguments();
946 List<Type> forms = type.tsym.type.getTypeArguments();
947 ListBuffer<Type> bounds_buf = new ListBuffer<Type>();
948
949 // For matching pairs of actual argument types `a' and
950 // formal type parameters with declared bound `b' ...
951 while (args.nonEmpty() && forms.nonEmpty()) {
952 // exact type arguments needs to know their
953 // bounds (for upper and lower bound
954 // calculations). So we create new bounds where
955 // type-parameters are replaced with actuals argument types.
956 bounds_buf.append(types.subst(forms.head.getUpperBound(), formals, actuals));
957 args = args.tail;
958 forms = forms.tail;
959 }
960
961 args = type.getTypeArguments();
962 List<Type> tvars_cap = types.substBounds(formals,
963 formals,
964 types.capture(type).allparams());
965 while (args.nonEmpty() && tvars_cap.nonEmpty()) {
966 // Let the actual arguments know their bound
967 args.head.withTypeVar((TypeVar)tvars_cap.head);
968 args = args.tail;
969 tvars_cap = tvars_cap.tail;
970 }
971
972 args = type.getTypeArguments();
973 List<Type> bounds = bounds_buf.toList();
974
975 while (args.nonEmpty() && bounds.nonEmpty()) {
976 Type actual = args.head;
977 if (!isTypeArgErroneous(actual) &&
978 !bounds.head.isErroneous() &&
979 !checkExtends(actual, bounds.head)) {
980 return args.head;
981 }
982 args = args.tail;
983 bounds = bounds.tail;
984 }
985
986 args = type.getTypeArguments();
987 bounds = bounds_buf.toList();
988
989 for (Type arg : types.capture(type).getTypeArguments()) {
990 if (arg.hasTag(TYPEVAR) &&
991 arg.getUpperBound().isErroneous() &&
992 !bounds.head.isErroneous() &&
993 !isTypeArgErroneous(args.head)) {
994 return args.head;
995 }
996 bounds = bounds.tail;
997 args = args.tail;
998 }
999
1000 return null;
1001 }
1002 //where
1003 boolean isTypeArgErroneous(Type t) {
1004 return isTypeArgErroneous.visit(t);
1005 }
1006
1007 Types.UnaryVisitor<Boolean> isTypeArgErroneous = new Types.UnaryVisitor<Boolean>() {
1008 public Boolean visitType(Type t, Void s) {
1009 return t.isErroneous();
1010 }
1011 @Override
1012 public Boolean visitTypeVar(TypeVar t, Void s) {
1013 return visit(t.getUpperBound());
1014 }
1015 @Override
1016 public Boolean visitCapturedType(CapturedType t, Void s) {
1017 return visit(t.getUpperBound()) ||
1018 visit(t.getLowerBound());
1019 }
1020 @Override
1021 public Boolean visitWildcardType(WildcardType t, Void s) {
1022 return visit(t.type);
1023 }
1024 };
1025
1026 /** Check that given modifiers are legal for given symbol and
1027 * return modifiers together with any implicit modifiers for that symbol.
1028 * Warning: we can't use flags() here since this method
1029 * is called during class enter, when flags() would cause a premature
1030 * completion.
1031 * @param pos Position to be used for error reporting.
1032 * @param flags The set of modifiers given in a definition.
1033 * @param sym The defined symbol.
1034 */
1035 long checkFlags(DiagnosticPosition pos, long flags, Symbol sym, JCTree tree) {
1036 long mask;
1037 long implicit = 0;
1038
1039 switch (sym.kind) {
1040 case VAR:
1041 if (TreeInfo.isReceiverParam(tree))
1042 mask = ReceiverParamFlags;
1043 else if (sym.owner.kind != TYP)
1044 mask = LocalVarFlags;
1045 else if ((sym.owner.flags_field & INTERFACE) != 0)
1046 mask = implicit = InterfaceVarFlags;
1047 else
1048 mask = VarFlags;
1049 break;
1050 case MTH:
1051 if (sym.name == names.init) {
1052 if ((sym.owner.flags_field & ENUM) != 0) {
1053 // enum constructors cannot be declared public or
1054 // protected and must be implicitly or explicitly
1055 // private
1056 implicit = PRIVATE;
1057 mask = PRIVATE;
1058 } else
1059 mask = ConstructorFlags;
1060 } else if ((sym.owner.flags_field & INTERFACE) != 0) {
1061 if ((sym.owner.flags_field & ANNOTATION) != 0) {
1062 mask = AnnotationTypeElementMask;
1063 implicit = PUBLIC | ABSTRACT;
1064 } else if ((flags & (DEFAULT | STATIC)) != 0) {
1065 mask = InterfaceMethodMask;
1066 implicit = PUBLIC;
1067 if ((flags & DEFAULT) != 0) {
1068 implicit |= ABSTRACT;
1069 }
1070 } else {
1071 mask = implicit = InterfaceMethodFlags;
1072 }
1073 } else {
1074 mask = MethodFlags;
1075 }
1076 // Imply STRICTFP if owner has STRICTFP set.
1077 if (((flags|implicit) & Flags.ABSTRACT) == 0 ||
1078 ((flags) & Flags.DEFAULT) != 0)
1079 implicit |= sym.owner.flags_field & STRICTFP;
1080 break;
1081 case TYP:
1082 if (sym.isLocal()) {
1083 mask = LocalClassFlags;
1084 if (sym.name.isEmpty()) { // Anonymous class
1085 // Anonymous classes in static methods are themselves static;
1086 // that's why we admit STATIC here.
1087 mask |= STATIC;
1088 // JLS: Anonymous classes are final.
1089 implicit |= FINAL;
1090 }
1091 if ((sym.owner.flags_field & STATIC) == 0 &&
1092 (flags & ENUM) != 0)
1093 log.error(pos, "enums.must.be.static");
1094 } else if (sym.owner.kind == TYP) {
1095 mask = MemberClassFlags;
1096 if (sym.owner.owner.kind == PCK ||
1097 (sym.owner.flags_field & STATIC) != 0)
1098 mask |= STATIC;
1099 else if ((flags & ENUM) != 0)
1100 log.error(pos, "enums.must.be.static");
1101 // Nested interfaces and enums are always STATIC (Spec ???)
1102 if ((flags & (INTERFACE | ENUM)) != 0 ) implicit = STATIC;
1103 } else {
1104 mask = ClassFlags;
1105 }
1106 // Interfaces are always ABSTRACT
1107 if ((flags & INTERFACE) != 0) implicit |= ABSTRACT;
1108
1109 if ((flags & ENUM) != 0) {
1110 // enums can't be declared abstract or final
1111 mask &= ~(ABSTRACT | FINAL);
1112 implicit |= implicitEnumFinalFlag(tree);
1113 }
1114 // Imply STRICTFP if owner has STRICTFP set.
1115 implicit |= sym.owner.flags_field & STRICTFP;
1116 break;
1117 default:
1118 throw new AssertionError();
1119 }
1120 long illegal = flags & ExtendedStandardFlags & ~mask;
1121 if (illegal != 0) {
1122 if ((illegal & INTERFACE) != 0) {
1123 log.error(pos, "intf.not.allowed.here");
1124 mask |= INTERFACE;
1125 }
1126 else {
1127 log.error(pos,
1128 "mod.not.allowed.here", asFlagSet(illegal));
1129 }
1130 }
1131 else if ((sym.kind == TYP ||
1132 // ISSUE: Disallowing abstract&private is no longer appropriate
1133 // in the presence of inner classes. Should it be deleted here?
1134 checkDisjoint(pos, flags,
1135 ABSTRACT,
1136 PRIVATE | STATIC | DEFAULT))
1137 &&
1138 checkDisjoint(pos, flags,
1139 STATIC,
1140 DEFAULT)
1141 &&
1142 checkDisjoint(pos, flags,
1143 ABSTRACT | INTERFACE,
1144 FINAL | NATIVE | SYNCHRONIZED)
1145 &&
1146 checkDisjoint(pos, flags,
1147 PUBLIC,
1148 PRIVATE | PROTECTED)
1149 &&
1150 checkDisjoint(pos, flags,
1151 PRIVATE,
1152 PUBLIC | PROTECTED)
1153 &&
1154 checkDisjoint(pos, flags,
1155 FINAL,
1156 VOLATILE)
1157 &&
1158 (sym.kind == TYP ||
1159 checkDisjoint(pos, flags,
1160 ABSTRACT | NATIVE,
1161 STRICTFP))) {
1162 // skip
1163 }
1164 return flags & (mask | ~ExtendedStandardFlags) | implicit;
1165 }
1166
1167
1168 /** Determine if this enum should be implicitly final.
1169 *
1170 * If the enum has no specialized enum contants, it is final.
1171 *
1172 * If the enum does have specialized enum contants, it is
1173 * <i>not</i> final.
1174 */
1175 private long implicitEnumFinalFlag(JCTree tree) {
1176 if (!tree.hasTag(CLASSDEF)) return 0;
1177 class SpecialTreeVisitor extends JCTree.Visitor {
1178 boolean specialized;
1179 SpecialTreeVisitor() {
1180 this.specialized = false;
1181 };
1182
1183 @Override
1184 public void visitTree(JCTree tree) { /* no-op */ }
1185
1186 @Override
1187 public void visitVarDef(JCVariableDecl tree) {
1188 if ((tree.mods.flags & ENUM) != 0) {
1189 if (tree.init instanceof JCNewClass &&
1190 ((JCNewClass) tree.init).def != null) {
1191 specialized = true;
1192 }
1193 }
1194 }
1195 }
1196
1197 SpecialTreeVisitor sts = new SpecialTreeVisitor();
1198 JCClassDecl cdef = (JCClassDecl) tree;
1199 for (JCTree defs: cdef.defs) {
1200 defs.accept(sts);
1201 if (sts.specialized) return 0;
1202 }
1203 return FINAL;
1204 }
1205
1206 /* *************************************************************************
1207 * Type Validation
1208 **************************************************************************/
1209
1210 /** Validate a type expression. That is,
1211 * check that all type arguments of a parametric type are within
1212 * their bounds. This must be done in a second phase after type attribution
1213 * since a class might have a subclass as type parameter bound. E.g:
1214 *
1215 * <pre>{@code
1216 * class B<A extends C> { ... }
1217 * class C extends B<C> { ... }
1218 * }</pre>
1219 *
1220 * and we can't make sure that the bound is already attributed because
1221 * of possible cycles.
1222 *
1223 * Visitor method: Validate a type expression, if it is not null, catching
1224 * and reporting any completion failures.
1225 */
1226 void validate(JCTree tree, Env<AttrContext> env) {
1227 validate(tree, env, true);
1228 }
1229 void validate(JCTree tree, Env<AttrContext> env, boolean checkRaw) {
1230 new Validator(env).validateTree(tree, checkRaw, true);
1231 }
1232
1233 /** Visitor method: Validate a list of type expressions.
1234 */
1235 void validate(List<? extends JCTree> trees, Env<AttrContext> env) {
1236 for (List<? extends JCTree> l = trees; l.nonEmpty(); l = l.tail)
1237 validate(l.head, env);
1238 }
1239
1240 /** A visitor class for type validation.
1241 */
1242 class Validator extends JCTree.Visitor {
1243
1244 boolean checkRaw;
1245 boolean isOuter;
1246 Env<AttrContext> env;
1247
1248 Validator(Env<AttrContext> env) {
1249 this.env = env;
1250 }
1251
1252 @Override
1253 public void visitTypeArray(JCArrayTypeTree tree) {
1254 validateTree(tree.elemtype, checkRaw, isOuter);
1255 }
1256
1257 @Override
1258 public void visitTypeApply(JCTypeApply tree) {
1259 if (tree.type.hasTag(CLASS)) {
1260 List<JCExpression> args = tree.arguments;
1261 List<Type> forms = tree.type.tsym.type.getTypeArguments();
1262
1263 Type incompatibleArg = firstIncompatibleTypeArg(tree.type);
1264 if (incompatibleArg != null) {
1265 for (JCTree arg : tree.arguments) {
1266 if (arg.type == incompatibleArg) {
1267 log.error(arg, "not.within.bounds", incompatibleArg, forms.head);
1268 }
1269 forms = forms.tail;
1270 }
1271 }
1272
1273 forms = tree.type.tsym.type.getTypeArguments();
1274
1275 boolean is_java_lang_Class = tree.type.tsym.flatName() == names.java_lang_Class;
1276
1277 // For matching pairs of actual argument types `a' and
1278 // formal type parameters with declared bound `b' ...
1279 while (args.nonEmpty() && forms.nonEmpty()) {
1280 validateTree(args.head,
1281 !(isOuter && is_java_lang_Class),
1282 false);
1283 args = args.tail;
1284 forms = forms.tail;
1285 }
1286
1287 // Check that this type is either fully parameterized, or
1288 // not parameterized at all.
1289 if (tree.type.getEnclosingType().isRaw())
1290 log.error(tree.pos(), "improperly.formed.type.inner.raw.param");
1291 if (tree.clazz.hasTag(SELECT))
1292 visitSelectInternal((JCFieldAccess)tree.clazz);
1293 }
1294 }
1295
1296 @Override
1297 public void visitTypeParameter(JCTypeParameter tree) {
1298 validateTrees(tree.bounds, true, isOuter);
1299 checkClassBounds(tree.pos(), tree.type);
1300 }
1301
1302 @Override
1303 public void visitWildcard(JCWildcard tree) {
1304 if (tree.inner != null)
1305 validateTree(tree.inner, true, isOuter);
1306 }
1307
1308 @Override
1309 public void visitSelect(JCFieldAccess tree) {
1310 if (tree.type.hasTag(CLASS)) {
1311 visitSelectInternal(tree);
1312
1313 // Check that this type is either fully parameterized, or
1314 // not parameterized at all.
1315 if (tree.selected.type.isParameterized() && tree.type.tsym.type.getTypeArguments().nonEmpty())
1316 log.error(tree.pos(), "improperly.formed.type.param.missing");
1317 }
1318 }
1319
1320 public void visitSelectInternal(JCFieldAccess tree) {
1321 if (tree.type.tsym.isStatic() &&
1322 tree.selected.type.isParameterized()) {
1323 // The enclosing type is not a class, so we are
1324 // looking at a static member type. However, the
1325 // qualifying expression is parameterized.
1326 log.error(tree.pos(), "cant.select.static.class.from.param.type");
1327 } else {
1328 // otherwise validate the rest of the expression
1329 tree.selected.accept(this);
1330 }
1331 }
1332
1333 @Override
1334 public void visitAnnotatedType(JCAnnotatedType tree) {
1335 tree.underlyingType.accept(this);
1336 }
1337
1338 @Override
1339 public void visitTypeIdent(JCPrimitiveTypeTree that) {
1340 if (that.type.hasTag(TypeTag.VOID)) {
1341 log.error(that.pos(), "void.not.allowed.here");
1342 }
1343 super.visitTypeIdent(that);
1344 }
1345
1346 /** Default visitor method: do nothing.
1347 */
1348 @Override
1349 public void visitTree(JCTree tree) {
1350 }
1351
1352 public void validateTree(JCTree tree, boolean checkRaw, boolean isOuter) {
1353 if (tree != null) {
1354 boolean prevCheckRaw = this.checkRaw;
1355 this.checkRaw = checkRaw;
1356 this.isOuter = isOuter;
1357
1358 try {
1359 tree.accept(this);
1360 if (checkRaw)
1361 checkRaw(tree, env);
1362 } catch (CompletionFailure ex) {
1363 completionError(tree.pos(), ex);
1364 } finally {
1365 this.checkRaw = prevCheckRaw;
1366 }
1367 }
1368 }
1369
1370 public void validateTrees(List<? extends JCTree> trees, boolean checkRaw, boolean isOuter) {
1371 for (List<? extends JCTree> l = trees; l.nonEmpty(); l = l.tail)
1372 validateTree(l.head, checkRaw, isOuter);
1373 }
1374 }
1375
1376 void checkRaw(JCTree tree, Env<AttrContext> env) {
1377 if (lint.isEnabled(LintCategory.RAW) &&
1378 tree.type.hasTag(CLASS) &&
1379 !TreeInfo.isDiamond(tree) &&
1380 !withinAnonConstr(env) &&
1381 tree.type.isRaw()) {
1382 log.warning(LintCategory.RAW,
1383 tree.pos(), "raw.class.use", tree.type, tree.type.tsym.type);
1384 }
1385 }
1386 //where
1387 private boolean withinAnonConstr(Env<AttrContext> env) {
1388 return env.enclClass.name.isEmpty() &&
1389 env.enclMethod != null && env.enclMethod.name == names.init;
1390 }
1391
1392 /* *************************************************************************
1393 * Exception checking
1394 **************************************************************************/
1395
1396 /* The following methods treat classes as sets that contain
1397 * the class itself and all their subclasses
1398 */
1399
1400 /** Is given type a subtype of some of the types in given list?
1401 */
1402 boolean subset(Type t, List<Type> ts) {
1403 for (List<Type> l = ts; l.nonEmpty(); l = l.tail)
1404 if (types.isSubtype(t, l.head)) return true;
1405 return false;
1406 }
1407
1408 /** Is given type a subtype or supertype of
1409 * some of the types in given list?
1410 */
1411 boolean intersects(Type t, List<Type> ts) {
1412 for (List<Type> l = ts; l.nonEmpty(); l = l.tail)
1413 if (types.isSubtype(t, l.head) || types.isSubtype(l.head, t)) return true;
1414 return false;
1415 }
1416
1417 /** Add type set to given type list, unless it is a subclass of some class
1418 * in the list.
1419 */
1420 List<Type> incl(Type t, List<Type> ts) {
1421 return subset(t, ts) ? ts : excl(t, ts).prepend(t);
1422 }
1423
1424 /** Remove type set from type set list.
1425 */
1426 List<Type> excl(Type t, List<Type> ts) {
1427 if (ts.isEmpty()) {
1428 return ts;
1429 } else {
1430 List<Type> ts1 = excl(t, ts.tail);
1431 if (types.isSubtype(ts.head, t)) return ts1;
1432 else if (ts1 == ts.tail) return ts;
1433 else return ts1.prepend(ts.head);
1434 }
1435 }
1436
1437 /** Form the union of two type set lists.
1438 */
1439 List<Type> union(List<Type> ts1, List<Type> ts2) {
1440 List<Type> ts = ts1;
1441 for (List<Type> l = ts2; l.nonEmpty(); l = l.tail)
1442 ts = incl(l.head, ts);
1443 return ts;
1444 }
1445
1446 /** Form the difference of two type lists.
1447 */
1448 List<Type> diff(List<Type> ts1, List<Type> ts2) {
1449 List<Type> ts = ts1;
1450 for (List<Type> l = ts2; l.nonEmpty(); l = l.tail)
1451 ts = excl(l.head, ts);
1452 return ts;
1453 }
1454
1455 /** Form the intersection of two type lists.
1456 */
1457 public List<Type> intersect(List<Type> ts1, List<Type> ts2) {
1458 List<Type> ts = List.nil();
1459 for (List<Type> l = ts1; l.nonEmpty(); l = l.tail)
1460 if (subset(l.head, ts2)) ts = incl(l.head, ts);
1461 for (List<Type> l = ts2; l.nonEmpty(); l = l.tail)
1462 if (subset(l.head, ts1)) ts = incl(l.head, ts);
1463 return ts;
1464 }
1465
1466 /** Is exc an exception symbol that need not be declared?
1467 */
1468 boolean isUnchecked(ClassSymbol exc) {
1469 return
1470 exc.kind == ERR ||
1471 exc.isSubClass(syms.errorType.tsym, types) ||
1472 exc.isSubClass(syms.runtimeExceptionType.tsym, types);
1473 }
1474
1475 /** Is exc an exception type that need not be declared?
1476 */
1477 boolean isUnchecked(Type exc) {
1478 return
1479 (exc.hasTag(TYPEVAR)) ? isUnchecked(types.supertype(exc)) :
1480 (exc.hasTag(CLASS)) ? isUnchecked((ClassSymbol)exc.tsym) :
1481 exc.hasTag(BOT);
1482 }
1483
1484 /** Same, but handling completion failures.
1485 */
1486 boolean isUnchecked(DiagnosticPosition pos, Type exc) {
1487 try {
1488 return isUnchecked(exc);
1489 } catch (CompletionFailure ex) {
1490 completionError(pos, ex);
1491 return true;
1492 }
1493 }
1494
1495 /** Is exc handled by given exception list?
1496 */
1497 boolean isHandled(Type exc, List<Type> handled) {
1498 return isUnchecked(exc) || subset(exc, handled);
1499 }
1500
1501 /** Return all exceptions in thrown list that are not in handled list.
1502 * @param thrown The list of thrown exceptions.
1503 * @param handled The list of handled exceptions.
1504 */
1505 List<Type> unhandled(List<Type> thrown, List<Type> handled) {
1506 List<Type> unhandled = List.nil();
1507 for (List<Type> l = thrown; l.nonEmpty(); l = l.tail)
1508 if (!isHandled(l.head, handled)) unhandled = unhandled.prepend(l.head);
1509 return unhandled;
1510 }
1511
1512 /* *************************************************************************
1513 * Overriding/Implementation checking
1514 **************************************************************************/
1515
1516 /** The level of access protection given by a flag set,
1517 * where PRIVATE is highest and PUBLIC is lowest.
1518 */
1519 static int protection(long flags) {
1520 switch ((short)(flags & AccessFlags)) {
1521 case PRIVATE: return 3;
1522 case PROTECTED: return 1;
1523 default:
1524 case PUBLIC: return 0;
1525 case 0: return 2;
1526 }
1527 }
1528
1529 /** A customized "cannot override" error message.
1530 * @param m The overriding method.
1531 * @param other The overridden method.
1532 * @return An internationalized string.
1533 */
1534 Object cannotOverride(MethodSymbol m, MethodSymbol other) {
1535 String key;
1536 if ((other.owner.flags() & INTERFACE) == 0)
1537 key = "cant.override";
1538 else if ((m.owner.flags() & INTERFACE) == 0)
1539 key = "cant.implement";
1540 else
1541 key = "clashes.with";
1542 return diags.fragment(key, m, m.location(), other, other.location());
1543 }
1544
1545 /** A customized "override" warning message.
1546 * @param m The overriding method.
1547 * @param other The overridden method.
1548 * @return An internationalized string.
1549 */
1550 Object uncheckedOverrides(MethodSymbol m, MethodSymbol other) {
1551 String key;
1552 if ((other.owner.flags() & INTERFACE) == 0)
1553 key = "unchecked.override";
1554 else if ((m.owner.flags() & INTERFACE) == 0)
1555 key = "unchecked.implement";
1556 else
1557 key = "unchecked.clash.with";
1558 return diags.fragment(key, m, m.location(), other, other.location());
1559 }
1560
1561 /** A customized "override" warning message.
1562 * @param m The overriding method.
1563 * @param other The overridden method.
1564 * @return An internationalized string.
1565 */
1566 Object varargsOverrides(MethodSymbol m, MethodSymbol other) {
1567 String key;
1568 if ((other.owner.flags() & INTERFACE) == 0)
1569 key = "varargs.override";
1570 else if ((m.owner.flags() & INTERFACE) == 0)
1571 key = "varargs.implement";
1572 else
1573 key = "varargs.clash.with";
1574 return diags.fragment(key, m, m.location(), other, other.location());
1575 }
1576
1577 /** Check that this method conforms with overridden method 'other'.
1578 * where `origin' is the class where checking started.
1579 * Complications:
1580 * (1) Do not check overriding of synthetic methods
1581 * (reason: they might be final).
1582 * todo: check whether this is still necessary.
1583 * (2) Admit the case where an interface proxy throws fewer exceptions
1584 * than the method it implements. Augment the proxy methods with the
1585 * undeclared exceptions in this case.
1586 * (3) When generics are enabled, admit the case where an interface proxy
1587 * has a result type
1588 * extended by the result type of the method it implements.
1589 * Change the proxies result type to the smaller type in this case.
1590 *
1591 * @param tree The tree from which positions
1592 * are extracted for errors.
1593 * @param m The overriding method.
1594 * @param other The overridden method.
1595 * @param origin The class of which the overriding method
1596 * is a member.
1597 */
1598 void checkOverride(JCTree tree,
1599 MethodSymbol m,
1600 MethodSymbol other,
1601 ClassSymbol origin) {
1602 // Don't check overriding of synthetic methods or by bridge methods.
1603 if ((m.flags() & (SYNTHETIC|BRIDGE)) != 0 || (other.flags() & SYNTHETIC) != 0) {
1604 return;
1605 }
1606
1607 // Error if static method overrides instance method (JLS 8.4.6.2).
1608 if ((m.flags() & STATIC) != 0 &&
1609 (other.flags() & STATIC) == 0) {
1610 log.error(TreeInfo.diagnosticPositionFor(m, tree), "override.static",
1611 cannotOverride(m, other));
1612 m.flags_field |= BAD_OVERRIDE;
1613 return;
1614 }
1615
1616 // Error if instance method overrides static or final
1617 // method (JLS 8.4.6.1).
1618 if ((other.flags() & FINAL) != 0 ||
1619 (m.flags() & STATIC) == 0 &&
1620 (other.flags() & STATIC) != 0) {
1621 log.error(TreeInfo.diagnosticPositionFor(m, tree), "override.meth",
1622 cannotOverride(m, other),
1623 asFlagSet(other.flags() & (FINAL | STATIC)));
1624 m.flags_field |= BAD_OVERRIDE;
1625 return;
1626 }
1627
1628 if ((m.owner.flags() & ANNOTATION) != 0) {
1629 // handled in validateAnnotationMethod
1630 return;
1631 }
1632
1633 // Error if overriding method has weaker access (JLS 8.4.6.3).
1634 if ((origin.flags() & INTERFACE) == 0 &&
1635 protection(m.flags()) > protection(other.flags())) {
1636 log.error(TreeInfo.diagnosticPositionFor(m, tree), "override.weaker.access",
1637 cannotOverride(m, other),
1638 other.flags() == 0 ?
1639 "package" :
1640 asFlagSet(other.flags() & AccessFlags));
1641 m.flags_field |= BAD_OVERRIDE;
1642 return;
1643 }
1644
1645 Type mt = types.memberType(origin.type, m);
1646 Type ot = types.memberType(origin.type, other);
1647 // Error if overriding result type is different
1648 // (or, in the case of generics mode, not a subtype) of
1649 // overridden result type. We have to rename any type parameters
1650 // before comparing types.
1651 List<Type> mtvars = mt.getTypeArguments();
1652 List<Type> otvars = ot.getTypeArguments();
1653 Type mtres = mt.getReturnType();
1654 Type otres = types.subst(ot.getReturnType(), otvars, mtvars);
1655
1656 overrideWarner.clear();
1657 boolean resultTypesOK =
1658 types.returnTypeSubstitutable(mt, ot, otres, overrideWarner);
1659 if (!resultTypesOK) {
1660 if (!allowCovariantReturns &&
1661 m.owner != origin &&
1662 m.owner.isSubClass(other.owner, types)) {
1663 // allow limited interoperability with covariant returns
1664 } else {
1665 log.error(TreeInfo.diagnosticPositionFor(m, tree),
1666 "override.incompatible.ret",
1667 cannotOverride(m, other),
1668 mtres, otres);
1669 m.flags_field |= BAD_OVERRIDE;
1670 return;
1671 }
1672 } else if (overrideWarner.hasNonSilentLint(LintCategory.UNCHECKED)) {
1673 warnUnchecked(TreeInfo.diagnosticPositionFor(m, tree),
1674 "override.unchecked.ret",
1675 uncheckedOverrides(m, other),
1676 mtres, otres);
1677 }
1678
1679 // Error if overriding method throws an exception not reported
1680 // by overridden method.
1681 List<Type> otthrown = types.subst(ot.getThrownTypes(), otvars, mtvars);
1682 List<Type> unhandledErased = unhandled(mt.getThrownTypes(), types.erasure(otthrown));
1683 List<Type> unhandledUnerased = unhandled(mt.getThrownTypes(), otthrown);
1684 if (unhandledErased.nonEmpty()) {
1685 log.error(TreeInfo.diagnosticPositionFor(m, tree),
1686 "override.meth.doesnt.throw",
1687 cannotOverride(m, other),
1688 unhandledUnerased.head);
1689 m.flags_field |= BAD_OVERRIDE;
1690 return;
1691 }
1692 else if (unhandledUnerased.nonEmpty()) {
1693 warnUnchecked(TreeInfo.diagnosticPositionFor(m, tree),
1694 "override.unchecked.thrown",
1695 cannotOverride(m, other),
1696 unhandledUnerased.head);
1697 return;
1698 }
1699
1700 // Optional warning if varargs don't agree
1701 if ((((m.flags() ^ other.flags()) & Flags.VARARGS) != 0)
1702 && lint.isEnabled(LintCategory.OVERRIDES)) {
1703 log.warning(TreeInfo.diagnosticPositionFor(m, tree),
1704 ((m.flags() & Flags.VARARGS) != 0)
1705 ? "override.varargs.missing"
1706 : "override.varargs.extra",
1707 varargsOverrides(m, other));
1708 }
1709
1710 // Warn if instance method overrides bridge method (compiler spec ??)
1711 if ((other.flags() & BRIDGE) != 0) {
1712 log.warning(TreeInfo.diagnosticPositionFor(m, tree), "override.bridge",
1713 uncheckedOverrides(m, other));
1714 }
1715
1716 // Warn if a deprecated method overridden by a non-deprecated one.
1717 if (!isDeprecatedOverrideIgnorable(other, origin)) {
1718 Lint prevLint = setLint(lint.augment(m));
1719 try {
1720 checkDeprecated(TreeInfo.diagnosticPositionFor(m, tree), m, other);
1721 } finally {
1722 setLint(prevLint);
1723 }
1724 }
1725 }
1726 // where
1727 private boolean isDeprecatedOverrideIgnorable(MethodSymbol m, ClassSymbol origin) {
1728 // If the method, m, is defined in an interface, then ignore the issue if the method
1729 // is only inherited via a supertype and also implemented in the supertype,
1730 // because in that case, we will rediscover the issue when examining the method
1731 // in the supertype.
1732 // If the method, m, is not defined in an interface, then the only time we need to
1733 // address the issue is when the method is the supertype implemementation: any other
1734 // case, we will have dealt with when examining the supertype classes
1735 ClassSymbol mc = m.enclClass();
1736 Type st = types.supertype(origin.type);
1737 if (!st.hasTag(CLASS))
1738 return true;
1739 MethodSymbol stimpl = m.implementation((ClassSymbol)st.tsym, types, false);
1740
1741 if (mc != null && ((mc.flags() & INTERFACE) != 0)) {
1742 List<Type> intfs = types.interfaces(origin.type);
1743 return (intfs.contains(mc.type) ? false : (stimpl != null));
1744 }
1745 else
1746 return (stimpl != m);
1747 }
1748
1749
1750 // used to check if there were any unchecked conversions
1751 Warner overrideWarner = new Warner();
1752
1753 /** Check that a class does not inherit two concrete methods
1754 * with the same signature.
1755 * @param pos Position to be used for error reporting.
1756 * @param site The class type to be checked.
1757 */
1758 public void checkCompatibleConcretes(DiagnosticPosition pos, Type site) {
1759 Type sup = types.supertype(site);
1760 if (!sup.hasTag(CLASS)) return;
1761
1762 for (Type t1 = sup;
1763 t1.hasTag(CLASS) && t1.tsym.type.isParameterized();
1764 t1 = types.supertype(t1)) {
1765 for (Scope.Entry e1 = t1.tsym.members().elems;
1766 e1 != null;
1767 e1 = e1.sibling) {
1768 Symbol s1 = e1.sym;
1769 if (s1.kind != MTH ||
1770 (s1.flags() & (STATIC|SYNTHETIC|BRIDGE)) != 0 ||
1771 !s1.isInheritedIn(site.tsym, types) ||
1772 ((MethodSymbol)s1).implementation(site.tsym,
1773 types,
1774 true) != s1)
1775 continue;
1776 Type st1 = types.memberType(t1, s1);
1777 int s1ArgsLength = st1.getParameterTypes().length();
1778 if (st1 == s1.type) continue;
1779
1780 for (Type t2 = sup;
1781 t2.hasTag(CLASS);
1782 t2 = types.supertype(t2)) {
1783 for (Scope.Entry e2 = t2.tsym.members().lookup(s1.name);
1784 e2.scope != null;
1785 e2 = e2.next()) {
1786 Symbol s2 = e2.sym;
1787 if (s2 == s1 ||
1788 s2.kind != MTH ||
1789 (s2.flags() & (STATIC|SYNTHETIC|BRIDGE)) != 0 ||
1790 s2.type.getParameterTypes().length() != s1ArgsLength ||
1791 !s2.isInheritedIn(site.tsym, types) ||
1792 ((MethodSymbol)s2).implementation(site.tsym,
1793 types,
1794 true) != s2)
1795 continue;
1796 Type st2 = types.memberType(t2, s2);
1797 if (types.overrideEquivalent(st1, st2))
1798 log.error(pos, "concrete.inheritance.conflict",
1799 s1, t1, s2, t2, sup);
1800 }
1801 }
1802 }
1803 }
1804 }
1805
1806 /** Check that classes (or interfaces) do not each define an abstract
1807 * method with same name and arguments but incompatible return types.
1808 * @param pos Position to be used for error reporting.
1809 * @param t1 The first argument type.
1810 * @param t2 The second argument type.
1811 */
1812 public boolean checkCompatibleAbstracts(DiagnosticPosition pos,
1813 Type t1,
1814 Type t2) {
1815 return checkCompatibleAbstracts(pos, t1, t2,
1816 types.makeCompoundType(t1, t2));
1817 }
1818
1819 public boolean checkCompatibleAbstracts(DiagnosticPosition pos,
1820 Type t1,
1821 Type t2,
1822 Type site) {
1823 if ((site.tsym.flags() & COMPOUND) != 0) {
1824 // special case for intersections: need to eliminate wildcards in supertypes
1825 t1 = types.capture(t1);
1826 t2 = types.capture(t2);
1827 }
1828 return firstIncompatibility(pos, t1, t2, site) == null;
1829 }
1830
1831 /** Return the first method which is defined with same args
1832 * but different return types in two given interfaces, or null if none
1833 * exists.
1834 * @param t1 The first type.
1835 * @param t2 The second type.
1836 * @param site The most derived type.
1837 * @returns symbol from t2 that conflicts with one in t1.
1838 */
1839 private Symbol firstIncompatibility(DiagnosticPosition pos, Type t1, Type t2, Type site) {
1840 Map<TypeSymbol,Type> interfaces1 = new HashMap<TypeSymbol,Type>();
1841 closure(t1, interfaces1);
1842 Map<TypeSymbol,Type> interfaces2;
1843 if (t1 == t2)
1844 interfaces2 = interfaces1;
1845 else
1846 closure(t2, interfaces1, interfaces2 = new HashMap<TypeSymbol,Type>());
1847
1848 for (Type t3 : interfaces1.values()) {
1849 for (Type t4 : interfaces2.values()) {
1850 Symbol s = firstDirectIncompatibility(pos, t3, t4, site);
1851 if (s != null) return s;
1852 }
1853 }
1854 return null;
1855 }
1856
1857 /** Compute all the supertypes of t, indexed by type symbol. */
1858 private void closure(Type t, Map<TypeSymbol,Type> typeMap) {
1859 if (!t.hasTag(CLASS)) return;
1860 if (typeMap.put(t.tsym, t) == null) {
1861 closure(types.supertype(t), typeMap);
1862 for (Type i : types.interfaces(t))
1863 closure(i, typeMap);
1864 }
1865 }
1866
1867 /** Compute all the supertypes of t, indexed by type symbol (except thise in typesSkip). */
1868 private void closure(Type t, Map<TypeSymbol,Type> typesSkip, Map<TypeSymbol,Type> typeMap) {
1869 if (!t.hasTag(CLASS)) return;
1870 if (typesSkip.get(t.tsym) != null) return;
1871 if (typeMap.put(t.tsym, t) == null) {
1872 closure(types.supertype(t), typesSkip, typeMap);
1873 for (Type i : types.interfaces(t))
1874 closure(i, typesSkip, typeMap);
1875 }
1876 }
1877
1878 /** Return the first method in t2 that conflicts with a method from t1. */
1879 private Symbol firstDirectIncompatibility(DiagnosticPosition pos, Type t1, Type t2, Type site) {
1880 for (Scope.Entry e1 = t1.tsym.members().elems; e1 != null; e1 = e1.sibling) {
1881 Symbol s1 = e1.sym;
1882 Type st1 = null;
1883 if (s1.kind != MTH || !s1.isInheritedIn(site.tsym, types) ||
1884 (s1.flags() & SYNTHETIC) != 0) continue;
1885 Symbol impl = ((MethodSymbol)s1).implementation(site.tsym, types, false);
1886 if (impl != null && (impl.flags() & ABSTRACT) == 0) continue;
1887 for (Scope.Entry e2 = t2.tsym.members().lookup(s1.name); e2.scope != null; e2 = e2.next()) {
1888 Symbol s2 = e2.sym;
1889 if (s1 == s2) continue;
1890 if (s2.kind != MTH || !s2.isInheritedIn(site.tsym, types) ||
1891 (s2.flags() & SYNTHETIC) != 0) continue;
1892 if (st1 == null) st1 = types.memberType(t1, s1);
1893 Type st2 = types.memberType(t2, s2);
1894 if (types.overrideEquivalent(st1, st2)) {
1895 List<Type> tvars1 = st1.getTypeArguments();
1896 List<Type> tvars2 = st2.getTypeArguments();
1897 Type rt1 = st1.getReturnType();
1898 Type rt2 = types.subst(st2.getReturnType(), tvars2, tvars1);
1899 boolean compat =
1900 types.isSameType(rt1, rt2) ||
1901 !rt1.isPrimitiveOrVoid() &&
1902 !rt2.isPrimitiveOrVoid() &&
1903 (types.covariantReturnType(rt1, rt2, types.noWarnings) ||
1904 types.covariantReturnType(rt2, rt1, types.noWarnings)) ||
1905 checkCommonOverriderIn(s1,s2,site);
1906 if (!compat) {
1907 log.error(pos, "types.incompatible.diff.ret",
1908 t1, t2, s2.name +
1909 "(" + types.memberType(t2, s2).getParameterTypes() + ")");
1910 return s2;
1911 }
1912 } else if (checkNameClash((ClassSymbol)site.tsym, s1, s2) &&
1913 !checkCommonOverriderIn(s1, s2, site)) {
1914 log.error(pos,
1915 "name.clash.same.erasure.no.override",
1916 s1, s1.location(),
1917 s2, s2.location());
1918 return s2;
1919 }
1920 }
1921 }
1922 return null;
1923 }
1924 //WHERE
1925 boolean checkCommonOverriderIn(Symbol s1, Symbol s2, Type site) {
1926 Map<TypeSymbol,Type> supertypes = new HashMap<TypeSymbol,Type>();
1927 Type st1 = types.memberType(site, s1);
1928 Type st2 = types.memberType(site, s2);
1929 closure(site, supertypes);
1930 for (Type t : supertypes.values()) {
1931 for (Scope.Entry e = t.tsym.members().lookup(s1.name); e.scope != null; e = e.next()) {
1932 Symbol s3 = e.sym;
1933 if (s3 == s1 || s3 == s2 || s3.kind != MTH || (s3.flags() & (BRIDGE|SYNTHETIC)) != 0) continue;
1934 Type st3 = types.memberType(site,s3);
1935 if (types.overrideEquivalent(st3, st1) &&
1936 types.overrideEquivalent(st3, st2) &&
1937 types.returnTypeSubstitutable(st3, st1) &&
1938 types.returnTypeSubstitutable(st3, st2)) {
1939 return true;
1940 }
1941 }
1942 }
1943 return false;
1944 }
1945
1946 /** Check that a given method conforms with any method it overrides.
1947 * @param tree The tree from which positions are extracted
1948 * for errors.
1949 * @param m The overriding method.
1950 */
1951 void checkOverride(JCMethodDecl tree, MethodSymbol m) {
1952 ClassSymbol origin = (ClassSymbol)m.owner;
1953 if ((origin.flags() & ENUM) != 0 && names.finalize.equals(m.name))
1954 if (m.overrides(syms.enumFinalFinalize, origin, types, false)) {
1955 log.error(tree.pos(), "enum.no.finalize");
1956 return;
1957 }
1958 for (Type t = origin.type; t.hasTag(CLASS);
1959 t = types.supertype(t)) {
1960 if (t != origin.type) {
1961 checkOverride(tree, t, origin, m);
1962 }
1963 for (Type t2 : types.interfaces(t)) {
1964 checkOverride(tree, t2, origin, m);
1965 }
1966 }
1967
1968 if (m.attribute(syms.overrideType.tsym) != null && !isOverrider(m)) {
1969 DiagnosticPosition pos = tree.pos();
1970 for (JCAnnotation a : tree.getModifiers().annotations) {
1971 if (a.annotationType.type.tsym == syms.overrideType.tsym) {
1972 pos = a.pos();
1973 break;
1974 }
1975 }
1976 log.error(pos, "method.does.not.override.superclass");
1977 }
1978 }
1979
1980 void checkOverride(JCTree tree, Type site, ClassSymbol origin, MethodSymbol m) {
1981 TypeSymbol c = site.tsym;
1982 Scope.Entry e = c.members().lookup(m.name);
1983 while (e.scope != null) {
1984 if (m.overrides(e.sym, origin, types, false)) {
1985 if ((e.sym.flags() & ABSTRACT) == 0) {
1986 checkOverride(tree, m, (MethodSymbol)e.sym, origin);
1987 }
1988 }
1989 e = e.next();
1990 }
1991 }
1992
1993 private Filter<Symbol> equalsHasCodeFilter = new Filter<Symbol>() {
1994 public boolean accepts(Symbol s) {
1995 return MethodSymbol.implementation_filter.accepts(s) &&
1996 (s.flags() & BAD_OVERRIDE) == 0;
1997
1998 }
1999 };
2000
2001 public void checkClassOverrideEqualsAndHashIfNeeded(DiagnosticPosition pos,
2002 ClassSymbol someClass) {
2003 /* At present, annotations cannot possibly have a method that is override
2004 * equivalent with Object.equals(Object) but in any case the condition is
2005 * fine for completeness.
2006 */
2007 if (someClass == (ClassSymbol)syms.objectType.tsym ||
2008 someClass.isInterface() || someClass.isEnum() ||
2009 (someClass.flags() & ANNOTATION) != 0 ||
2010 (someClass.flags() & ABSTRACT) != 0) return;
2011 //anonymous inner classes implementing interfaces need especial treatment
2012 if (someClass.isAnonymous()) {
2013 List<Type> interfaces = types.interfaces(someClass.type);
2014 if (interfaces != null && !interfaces.isEmpty() &&
2015 interfaces.head.tsym == syms.comparatorType.tsym) return;
2016 }
2017 checkClassOverrideEqualsAndHash(pos, someClass);
2018 }
2019
2020 private void checkClassOverrideEqualsAndHash(DiagnosticPosition pos,
2021 ClassSymbol someClass) {
2022 if (lint.isEnabled(LintCategory.OVERRIDES)) {
2023 MethodSymbol equalsAtObject = (MethodSymbol)syms.objectType
2024 .tsym.members().lookup(names.equals).sym;
2025 MethodSymbol hashCodeAtObject = (MethodSymbol)syms.objectType
2026 .tsym.members().lookup(names.hashCode).sym;
2027 boolean overridesEquals = types.implementation(equalsAtObject,
2028 someClass, false, equalsHasCodeFilter).owner == someClass;
2029 boolean overridesHashCode = types.implementation(hashCodeAtObject,
2030 someClass, false, equalsHasCodeFilter) != hashCodeAtObject;
2031
2032 if (overridesEquals && !overridesHashCode) {
2033 log.warning(LintCategory.OVERRIDES, pos,
2034 "override.equals.but.not.hashcode", someClass);
2035 }
2036 }
2037 }
2038
2039 private boolean checkNameClash(ClassSymbol origin, Symbol s1, Symbol s2) {
2040 ClashFilter cf = new ClashFilter(origin.type);
2041 return (cf.accepts(s1) &&
2042 cf.accepts(s2) &&
2043 types.hasSameArgs(s1.erasure(types), s2.erasure(types)));
2044 }
2045
2046
2047 /** Check that all abstract members of given class have definitions.
2048 * @param pos Position to be used for error reporting.
2049 * @param c The class.
2050 */
2051 void checkAllDefined(DiagnosticPosition pos, ClassSymbol c) {
2052 MethodSymbol undef = types.firstUnimplementedAbstract(c);
2053 if (undef != null) {
2054 MethodSymbol undef1 =
2055 new MethodSymbol(undef.flags(), undef.name,
2056 types.memberType(c.type, undef), undef.owner);
2057 log.error(pos, "does.not.override.abstract",
2058 c, undef1, undef1.location());
2059 }
2060 }
2061
2062 void checkNonCyclicDecl(JCClassDecl tree) {
2063 CycleChecker cc = new CycleChecker();
2064 cc.scan(tree);
2065 if (!cc.errorFound && !cc.partialCheck) {
2066 tree.sym.flags_field |= ACYCLIC;
2067 }
2068 }
2069
2070 class CycleChecker extends TreeScanner {
2071
2072 List<Symbol> seenClasses = List.nil();
2073 boolean errorFound = false;
2074 boolean partialCheck = false;
2075
2076 private void checkSymbol(DiagnosticPosition pos, Symbol sym) {
2077 if (sym != null && sym.kind == TYP) {
2078 Env<AttrContext> classEnv = enter.getEnv((TypeSymbol)sym);
2079 if (classEnv != null) {
2080 DiagnosticSource prevSource = log.currentSource();
2081 try {
2082 log.useSource(classEnv.toplevel.sourcefile);
2083 scan(classEnv.tree);
2084 }
2085 finally {
2086 log.useSource(prevSource.getFile());
2087 }
2088 } else if (sym.kind == TYP) {
2089 checkClass(pos, sym, List.<JCTree>nil());
2090 }
2091 } else {
2092 //not completed yet
2093 partialCheck = true;
2094 }
2095 }
2096
2097 @Override
2098 public void visitSelect(JCFieldAccess tree) {
2099 super.visitSelect(tree);
2100 checkSymbol(tree.pos(), tree.sym);
2101 }
2102
2103 @Override
2104 public void visitIdent(JCIdent tree) {
2105 checkSymbol(tree.pos(), tree.sym);
2106 }
2107
2108 @Override
2109 public void visitTypeApply(JCTypeApply tree) {
2110 scan(tree.clazz);
2111 }
2112
2113 @Override
2114 public void visitTypeArray(JCArrayTypeTree tree) {
2115 scan(tree.elemtype);
2116 }
2117
2118 @Override
2119 public void visitClassDef(JCClassDecl tree) {
2120 List<JCTree> supertypes = List.nil();
2121 if (tree.getExtendsClause() != null) {
2122 supertypes = supertypes.prepend(tree.getExtendsClause());
2123 }
2124 if (tree.getImplementsClause() != null) {
2125 for (JCTree intf : tree.getImplementsClause()) {
2126 supertypes = supertypes.prepend(intf);
2127 }
2128 }
2129 checkClass(tree.pos(), tree.sym, supertypes);
2130 }
2131
2132 void checkClass(DiagnosticPosition pos, Symbol c, List<JCTree> supertypes) {
2133 if ((c.flags_field & ACYCLIC) != 0)
2134 return;
2135 if (seenClasses.contains(c)) {
2136 errorFound = true;
2137 noteCyclic(pos, (ClassSymbol)c);
2138 } else if (!c.type.isErroneous()) {
2139 try {
2140 seenClasses = seenClasses.prepend(c);
2141 if (c.type.hasTag(CLASS)) {
2142 if (supertypes.nonEmpty()) {
2143 scan(supertypes);
2144 }
2145 else {
2146 ClassType ct = (ClassType)c.type;
2147 if (ct.supertype_field == null ||
2148 ct.interfaces_field == null) {
2149 //not completed yet
2150 partialCheck = true;
2151 return;
2152 }
2153 checkSymbol(pos, ct.supertype_field.tsym);
2154 for (Type intf : ct.interfaces_field) {
2155 checkSymbol(pos, intf.tsym);
2156 }
2157 }
2158 if (c.owner.kind == TYP) {
2159 checkSymbol(pos, c.owner);
2160 }
2161 }
2162 } finally {
2163 seenClasses = seenClasses.tail;
2164 }
2165 }
2166 }
2167 }
2168
2169 /** Check for cyclic references. Issue an error if the
2170 * symbol of the type referred to has a LOCKED flag set.
2171 *
2172 * @param pos Position to be used for error reporting.
2173 * @param t The type referred to.
2174 */
2175 void checkNonCyclic(DiagnosticPosition pos, Type t) {
2176 checkNonCyclicInternal(pos, t);
2177 }
2178
2179
2180 void checkNonCyclic(DiagnosticPosition pos, TypeVar t) {
2181 checkNonCyclic1(pos, t, List.<TypeVar>nil());
2182 }
2183
2184 private void checkNonCyclic1(DiagnosticPosition pos, Type t, List<TypeVar> seen) {
2185 final TypeVar tv;
2186 if (t.hasTag(TYPEVAR) && (t.tsym.flags() & UNATTRIBUTED) != 0)
2187 return;
2188 if (seen.contains(t)) {
2189 tv = (TypeVar)t.unannotatedType();
2190 tv.bound = types.createErrorType(t);
2191 log.error(pos, "cyclic.inheritance", t);
2192 } else if (t.hasTag(TYPEVAR)) {
2193 tv = (TypeVar)t.unannotatedType();
2194 seen = seen.prepend(tv);
2195 for (Type b : types.getBounds(tv))
2196 checkNonCyclic1(pos, b, seen);
2197 }
2198 }
2199
2200 /** Check for cyclic references. Issue an error if the
2201 * symbol of the type referred to has a LOCKED flag set.
2202 *
2203 * @param pos Position to be used for error reporting.
2204 * @param t The type referred to.
2205 * @returns True if the check completed on all attributed classes
2206 */
2207 private boolean checkNonCyclicInternal(DiagnosticPosition pos, Type t) {
2208 boolean complete = true; // was the check complete?
2209 //- System.err.println("checkNonCyclicInternal("+t+");");//DEBUG
2210 Symbol c = t.tsym;
2211 if ((c.flags_field & ACYCLIC) != 0) return true;
2212
2213 if ((c.flags_field & LOCKED) != 0) {
2214 noteCyclic(pos, (ClassSymbol)c);
2215 } else if (!c.type.isErroneous()) {
2216 try {
2217 c.flags_field |= LOCKED;
2218 if (c.type.hasTag(CLASS)) {
2219 ClassType clazz = (ClassType)c.type;
2220 if (clazz.interfaces_field != null)
2221 for (List<Type> l=clazz.interfaces_field; l.nonEmpty(); l=l.tail)
2222 complete &= checkNonCyclicInternal(pos, l.head);
2223 if (clazz.supertype_field != null) {
2224 Type st = clazz.supertype_field;
2225 if (st != null && st.hasTag(CLASS))
2226 complete &= checkNonCyclicInternal(pos, st);
2227 }
2228 if (c.owner.kind == TYP)
2229 complete &= checkNonCyclicInternal(pos, c.owner.type);
2230 }
2231 } finally {
2232 c.flags_field &= ~LOCKED;
2233 }
2234 }
2235 if (complete)
2236 complete = ((c.flags_field & UNATTRIBUTED) == 0) && c.completer == null;
2237 if (complete) c.flags_field |= ACYCLIC;
2238 return complete;
2239 }
2240
2241 /** Note that we found an inheritance cycle. */
2242 private void noteCyclic(DiagnosticPosition pos, ClassSymbol c) {
2243 log.error(pos, "cyclic.inheritance", c);
2244 for (List<Type> l=types.interfaces(c.type); l.nonEmpty(); l=l.tail)
2245 l.head = types.createErrorType((ClassSymbol)l.head.tsym, Type.noType);
2246 Type st = types.supertype(c.type);
2247 if (st.hasTag(CLASS))
2248 ((ClassType)c.type).supertype_field = types.createErrorType((ClassSymbol)st.tsym, Type.noType);
2249 c.type = types.createErrorType(c, c.type);
2250 c.flags_field |= ACYCLIC;
2251 }
2252
2253 /** Check that all methods which implement some
2254 * method conform to the method they implement.
2255 * @param tree The class definition whose members are checked.
2256 */
2257 void checkImplementations(JCClassDecl tree) {
2258 checkImplementations(tree, tree.sym, tree.sym);
2259 }
2260 //where
2261 /** Check that all methods which implement some
2262 * method in `ic' conform to the method they implement.
2263 */
2264 void checkImplementations(JCTree tree, ClassSymbol origin, ClassSymbol ic) {
2265 for (List<Type> l = types.closure(ic.type); l.nonEmpty(); l = l.tail) {
2266 ClassSymbol lc = (ClassSymbol)l.head.tsym;
2267 if ((allowGenerics || origin != lc) && (lc.flags() & ABSTRACT) != 0) {
2268 for (Scope.Entry e=lc.members().elems; e != null; e=e.sibling) {
2269 if (e.sym.kind == MTH &&
2270 (e.sym.flags() & (STATIC|ABSTRACT)) == ABSTRACT) {
2271 MethodSymbol absmeth = (MethodSymbol)e.sym;
2272 MethodSymbol implmeth = absmeth.implementation(origin, types, false);
2273 if (implmeth != null && implmeth != absmeth &&
2274 (implmeth.owner.flags() & INTERFACE) ==
2275 (origin.flags() & INTERFACE)) {
2276 // don't check if implmeth is in a class, yet
2277 // origin is an interface. This case arises only
2278 // if implmeth is declared in Object. The reason is
2279 // that interfaces really don't inherit from
2280 // Object it's just that the compiler represents
2281 // things that way.
2282 checkOverride(tree, implmeth, absmeth, origin);
2283 }
2284 }
2285 }
2286 }
2287 }
2288 }
2289
2290 /** Check that all abstract methods implemented by a class are
2291 * mutually compatible.
2292 * @param pos Position to be used for error reporting.
2293 * @param c The class whose interfaces are checked.
2294 */
2295 void checkCompatibleSupertypes(DiagnosticPosition pos, Type c) {
2296 List<Type> supertypes = types.interfaces(c);
2297 Type supertype = types.supertype(c);
2298 if (supertype.hasTag(CLASS) &&
2299 (supertype.tsym.flags() & ABSTRACT) != 0)
2300 supertypes = supertypes.prepend(supertype);
2301 for (List<Type> l = supertypes; l.nonEmpty(); l = l.tail) {
2302 if (allowGenerics && !l.head.getTypeArguments().isEmpty() &&
2303 !checkCompatibleAbstracts(pos, l.head, l.head, c))
2304 return;
2305 for (List<Type> m = supertypes; m != l; m = m.tail)
2306 if (!checkCompatibleAbstracts(pos, l.head, m.head, c))
2307 return;
2308 }
2309 checkCompatibleConcretes(pos, c);
2310 }
2311
2312 void checkConflicts(DiagnosticPosition pos, Symbol sym, TypeSymbol c) {
2313 for (Type ct = c.type; ct != Type.noType ; ct = types.supertype(ct)) {
2314 for (Scope.Entry e = ct.tsym.members().lookup(sym.name); e.scope == ct.tsym.members(); e = e.next()) {
2315 // VM allows methods and variables with differing types
2316 if (sym.kind == e.sym.kind &&
2317 types.isSameType(types.erasure(sym.type), types.erasure(e.sym.type)) &&
2318 sym != e.sym &&
2319 (sym.flags() & Flags.SYNTHETIC) != (e.sym.flags() & Flags.SYNTHETIC) &&
2320 (sym.flags() & IPROXY) == 0 && (e.sym.flags() & IPROXY) == 0 &&
2321 (sym.flags() & BRIDGE) == 0 && (e.sym.flags() & BRIDGE) == 0) {
2322 syntheticError(pos, (e.sym.flags() & SYNTHETIC) == 0 ? e.sym : sym);
2323 return;
2324 }
2325 }
2326 }
2327 }
2328
2329 /** Check that all non-override equivalent methods accessible from 'site'
2330 * are mutually compatible (JLS 8.4.8/9.4.1).
2331 *
2332 * @param pos Position to be used for error reporting.
2333 * @param site The class whose methods are checked.
2334 * @param sym The method symbol to be checked.
2335 */
2336 void checkOverrideClashes(DiagnosticPosition pos, Type site, MethodSymbol sym) {
2337 ClashFilter cf = new ClashFilter(site);
2338 //for each method m1 that is overridden (directly or indirectly)
2339 //by method 'sym' in 'site'...
2340
2341 List<MethodSymbol> potentiallyAmbiguousList = List.nil();
2342 boolean overridesAny = false;
2343 for (Symbol m1 : types.membersClosure(site, false).getElementsByName(sym.name, cf)) {
2344 if (!sym.overrides(m1, site.tsym, types, false)) {
2345 if (m1 == sym) {
2346 continue;
2347 }
2348
2349 if (!overridesAny) {
2350 potentiallyAmbiguousList = potentiallyAmbiguousList.prepend((MethodSymbol)m1);
2351 }
2352 continue;
2353 }
2354
2355 if (m1 != sym) {
2356 overridesAny = true;
2357 potentiallyAmbiguousList = List.nil();
2358 }
2359
2360 //...check each method m2 that is a member of 'site'
2361 for (Symbol m2 : types.membersClosure(site, false).getElementsByName(sym.name, cf)) {
2362 if (m2 == m1) continue;
2363 //if (i) the signature of 'sym' is not a subsignature of m1 (seen as
2364 //a member of 'site') and (ii) m1 has the same erasure as m2, issue an error
2365 if (!types.isSubSignature(sym.type, types.memberType(site, m2), allowStrictMethodClashCheck) &&
2366 types.hasSameArgs(m2.erasure(types), m1.erasure(types))) {
2367 sym.flags_field |= CLASH;
2368 String key = m1 == sym ?
2369 "name.clash.same.erasure.no.override" :
2370 "name.clash.same.erasure.no.override.1";
2371 log.error(pos,
2372 key,
2373 sym, sym.location(),
2374 m2, m2.location(),
2375 m1, m1.location());
2376 return;
2377 }
2378 }
2379 }
2380
2381 if (!overridesAny) {
2382 for (MethodSymbol m: potentiallyAmbiguousList) {
2383 checkPotentiallyAmbiguousOverloads(pos, site, sym, m);
2384 }
2385 }
2386 }
2387
2388 /** Check that all static methods accessible from 'site' are
2389 * mutually compatible (JLS 8.4.8).
2390 *
2391 * @param pos Position to be used for error reporting.
2392 * @param site The class whose methods are checked.
2393 * @param sym The method symbol to be checked.
2394 */
2395 void checkHideClashes(DiagnosticPosition pos, Type site, MethodSymbol sym) {
2396 ClashFilter cf = new ClashFilter(site);
2397 //for each method m1 that is a member of 'site'...
2398 for (Symbol s : types.membersClosure(site, true).getElementsByName(sym.name, cf)) {
2399 //if (i) the signature of 'sym' is not a subsignature of m1 (seen as
2400 //a member of 'site') and (ii) 'sym' has the same erasure as m1, issue an error
2401 if (!types.isSubSignature(sym.type, types.memberType(site, s), allowStrictMethodClashCheck)) {
2402 if (types.hasSameArgs(s.erasure(types), sym.erasure(types))) {
2403 log.error(pos,
2404 "name.clash.same.erasure.no.hide",
2405 sym, sym.location(),
2406 s, s.location());
2407 return;
2408 } else {
2409 checkPotentiallyAmbiguousOverloads(pos, site, sym, (MethodSymbol)s);
2410 }
2411 }
2412 }
2413 }
2414
2415 //where
2416 private class ClashFilter implements Filter<Symbol> {
2417
2418 Type site;
2419
2420 ClashFilter(Type site) {
2421 this.site = site;
2422 }
2423
2424 boolean shouldSkip(Symbol s) {
2425 return (s.flags() & CLASH) != 0 &&
2426 s.owner == site.tsym;
2427 }
2428
2429 public boolean accepts(Symbol s) {
2430 return s.kind == MTH &&
2431 (s.flags() & SYNTHETIC) == 0 &&
2432 !shouldSkip(s) &&
2433 s.isInheritedIn(site.tsym, types) &&
2434 !s.isConstructor();
2435 }
2436 }
2437
2438 void checkDefaultMethodClashes(DiagnosticPosition pos, Type site) {
2439 DefaultMethodClashFilter dcf = new DefaultMethodClashFilter(site);
2440 for (Symbol m : types.membersClosure(site, false).getElements(dcf)) {
2441 Assert.check(m.kind == MTH);
2442 List<MethodSymbol> prov = types.interfaceCandidates(site, (MethodSymbol)m);
2443 if (prov.size() > 1) {
2444 ListBuffer<Symbol> abstracts = new ListBuffer<>();
2445 ListBuffer<Symbol> defaults = new ListBuffer<>();
2446 for (MethodSymbol provSym : prov) {
2447 if ((provSym.flags() & DEFAULT) != 0) {
2448 defaults = defaults.append(provSym);
2449 } else if ((provSym.flags() & ABSTRACT) != 0) {
2450 abstracts = abstracts.append(provSym);
2451 }
2452 if (defaults.nonEmpty() && defaults.size() + abstracts.size() >= 2) {
2453 //strong semantics - issue an error if two sibling interfaces
2454 //have two override-equivalent defaults - or if one is abstract
2455 //and the other is default
2456 String errKey;
2457 Symbol s1 = defaults.first();
2458 Symbol s2;
2459 if (defaults.size() > 1) {
2460 errKey = "types.incompatible.unrelated.defaults";
2461 s2 = defaults.toList().tail.head;
2462 } else {
2463 errKey = "types.incompatible.abstract.default";
2464 s2 = abstracts.first();
2465 }
2466 log.error(pos, errKey,
2467 Kinds.kindName(site.tsym), site,
2468 m.name, types.memberType(site, m).getParameterTypes(),
2469 s1.location(), s2.location());
2470 break;
2471 }
2472 }
2473 }
2474 }
2475 }
2476
2477 //where
2478 private class DefaultMethodClashFilter implements Filter<Symbol> {
2479
2480 Type site;
2481
2482 DefaultMethodClashFilter(Type site) {
2483 this.site = site;
2484 }
2485
2486 public boolean accepts(Symbol s) {
2487 return s.kind == MTH &&
2488 (s.flags() & DEFAULT) != 0 &&
2489 s.isInheritedIn(site.tsym, types) &&
2490 !s.isConstructor();
2491 }
2492 }
2493
2494 /**
2495 * Report warnings for potentially ambiguous method declarations. Two declarations
2496 * are potentially ambiguous if they feature two unrelated functional interface
2497 * in same argument position (in which case, a call site passing an implicit
2498 * lambda would be ambiguous).
2499 */
2500 void checkPotentiallyAmbiguousOverloads(DiagnosticPosition pos, Type site,
2501 MethodSymbol msym1, MethodSymbol msym2) {
2502 if (msym1 != msym2 &&
2503 allowDefaultMethods &&
2504 lint.isEnabled(LintCategory.OVERLOADS) &&
2505 (msym1.flags() & POTENTIALLY_AMBIGUOUS) == 0 &&
2506 (msym2.flags() & POTENTIALLY_AMBIGUOUS) == 0) {
2507 Type mt1 = types.memberType(site, msym1);
2508 Type mt2 = types.memberType(site, msym2);
2509 //if both generic methods, adjust type variables
2510 if (mt1.hasTag(FORALL) && mt2.hasTag(FORALL) &&
2511 types.hasSameBounds((ForAll)mt1, (ForAll)mt2)) {
2512 mt2 = types.subst(mt2, ((ForAll)mt2).tvars, ((ForAll)mt1).tvars);
2513 }
2514 //expand varargs methods if needed
2515 int maxLength = Math.max(mt1.getParameterTypes().length(), mt2.getParameterTypes().length());
2516 List<Type> args1 = rs.adjustArgs(mt1.getParameterTypes(), msym1, maxLength, true);
2517 List<Type> args2 = rs.adjustArgs(mt2.getParameterTypes(), msym2, maxLength, true);
2518 //if arities don't match, exit
2519 if (args1.length() != args2.length()) return;
2520 boolean potentiallyAmbiguous = false;
2521 while (args1.nonEmpty() && args2.nonEmpty()) {
2522 Type s = args1.head;
2523 Type t = args2.head;
2524 if (!types.isSubtype(t, s) && !types.isSubtype(s, t)) {
2525 if (types.isFunctionalInterface(s) && types.isFunctionalInterface(t) &&
2526 types.findDescriptorType(s).getParameterTypes().length() > 0 &&
2527 types.findDescriptorType(s).getParameterTypes().length() ==
2528 types.findDescriptorType(t).getParameterTypes().length()) {
2529 potentiallyAmbiguous = true;
2530 } else {
2531 break;
2532 }
2533 }
2534 args1 = args1.tail;
2535 args2 = args2.tail;
2536 }
2537 if (potentiallyAmbiguous) {
2538 //we found two incompatible functional interfaces with same arity
2539 //this means a call site passing an implicit lambda would be ambigiuous
2540 msym1.flags_field |= POTENTIALLY_AMBIGUOUS;
2541 msym2.flags_field |= POTENTIALLY_AMBIGUOUS;
2542 log.warning(LintCategory.OVERLOADS, pos, "potentially.ambiguous.overload",
2543 msym1, msym1.location(),
2544 msym2, msym2.location());
2545 return;
2546 }
2547 }
2548 }
2549
2550 void checkElemAccessFromSerializableLambda(final JCTree tree) {
2551 if (warnOnAccessToSensitiveMembers) {
2552 Symbol sym = TreeInfo.symbol(tree);
2553 if ((sym.kind & (VAR | MTH)) == 0) {
2554 return;
2555 }
2556
2557 if (sym.kind == VAR) {
2558 if ((sym.flags() & PARAMETER) != 0 ||
2559 sym.isLocal() ||
2560 sym.name == names._this ||
2561 sym.name == names._super) {
2562 return;
2563 }
2564 }
2565
2566 if (!types.isSubtype(sym.owner.type, syms.serializableType) &&
2567 isEffectivelyNonPublic(sym)) {
2568 log.warning(tree.pos(),
2569 "access.to.sensitive.member.from.serializable.element", sym);
2570 }
2571 }
2572 }
2573
2574 private boolean isEffectivelyNonPublic(Symbol sym) {
2575 if (sym.packge() == syms.rootPackage) {
2576 return false;
2577 }
2578
2579 while (sym.kind != Kinds.PCK) {
2580 if ((sym.flags() & PUBLIC) == 0) {
2581 return true;
2582 }
2583 sym = sym.owner;
2584 }
2585 return false;
2586 }
2587
2588 /** Report a conflict between a user symbol and a synthetic symbol.
2589 */
2590 private void syntheticError(DiagnosticPosition pos, Symbol sym) {
2591 if (!sym.type.isErroneous()) {
2592 if (warnOnSyntheticConflicts) {
2593 log.warning(pos, "synthetic.name.conflict", sym, sym.location());
2594 }
2595 else {
2596 log.error(pos, "synthetic.name.conflict", sym, sym.location());
2597 }
2598 }
2599 }
2600
2601 /** Check that class c does not implement directly or indirectly
2602 * the same parameterized interface with two different argument lists.
2603 * @param pos Position to be used for error reporting.
2604 * @param type The type whose interfaces are checked.
2605 */
2606 void checkClassBounds(DiagnosticPosition pos, Type type) {
2607 checkClassBounds(pos, new HashMap<TypeSymbol,Type>(), type);
2608 }
2609 //where
2610 /** Enter all interfaces of type `type' into the hash table `seensofar'
2611 * with their class symbol as key and their type as value. Make
2612 * sure no class is entered with two different types.
2613 */
2614 void checkClassBounds(DiagnosticPosition pos,
2615 Map<TypeSymbol,Type> seensofar,
2616 Type type) {
2617 if (type.isErroneous()) return;
2618 for (List<Type> l = types.interfaces(type); l.nonEmpty(); l = l.tail) {
2619 Type it = l.head;
2620 Type oldit = seensofar.put(it.tsym, it);
2621 if (oldit != null) {
2622 List<Type> oldparams = oldit.allparams();
2623 List<Type> newparams = it.allparams();
2624 if (!types.containsTypeEquivalent(oldparams, newparams))
2625 log.error(pos, "cant.inherit.diff.arg",
2626 it.tsym, Type.toString(oldparams),
2627 Type.toString(newparams));
2628 }
2629 checkClassBounds(pos, seensofar, it);
2630 }
2631 Type st = types.supertype(type);
2632 if (st != Type.noType) checkClassBounds(pos, seensofar, st);
2633 }
2634
2635 /** Enter interface into into set.
2636 * If it existed already, issue a "repeated interface" error.
2637 */
2638 void checkNotRepeated(DiagnosticPosition pos, Type it, Set<Type> its) {
2639 if (its.contains(it))
2640 log.error(pos, "repeated.interface");
2641 else {
2642 its.add(it);
2643 }
2644 }
2645
2646 /* *************************************************************************
2647 * Check annotations
2648 **************************************************************************/
2649
2650 /**
2651 * Recursively validate annotations values
2652 */
2653 void validateAnnotationTree(JCTree tree) {
2654 class AnnotationValidator extends TreeScanner {
2655 @Override
2656 public void visitAnnotation(JCAnnotation tree) {
2657 if (!tree.type.isErroneous()) {
2658 super.visitAnnotation(tree);
2659 validateAnnotation(tree);
2660 }
2661 }
2662 }
2663 tree.accept(new AnnotationValidator());
2664 }
2665
2666 /**
2667 * {@literal
2668 * Annotation types are restricted to primitives, String, an
2669 * enum, an annotation, Class, Class<?>, Class<? extends
2670 * Anything>, arrays of the preceding.
2671 * }
2672 */
2673 void validateAnnotationType(JCTree restype) {
2674 // restype may be null if an error occurred, so don't bother validating it
2675 if (restype != null) {
2676 validateAnnotationType(restype.pos(), restype.type);
2677 }
2678 }
2679
2680 void validateAnnotationType(DiagnosticPosition pos, Type type) {
2681 if (type.isPrimitive()) return;
2682 if (types.isSameType(type, syms.stringType)) return;
2683 if ((type.tsym.flags() & Flags.ENUM) != 0) return;
2684 if ((type.tsym.flags() & Flags.ANNOTATION) != 0) return;
2685 if (types.cvarLowerBound(type).tsym == syms.classType.tsym) return;
2686 if (types.isArray(type) && !types.isArray(types.elemtype(type))) {
2687 validateAnnotationType(pos, types.elemtype(type));
2688 return;
2689 }
2690 log.error(pos, "invalid.annotation.member.type");
2691 }
2692
2693 /**
2694 * "It is also a compile-time error if any method declared in an
2695 * annotation type has a signature that is override-equivalent to
2696 * that of any public or protected method declared in class Object
2697 * or in the interface annotation.Annotation."
2698 *
2699 * @jls 9.6 Annotation Types
2700 */
2701 void validateAnnotationMethod(DiagnosticPosition pos, MethodSymbol m) {
2702 for (Type sup = syms.annotationType; sup.hasTag(CLASS); sup = types.supertype(sup)) {
2703 Scope s = sup.tsym.members();
2704 for (Scope.Entry e = s.lookup(m.name); e.scope != null; e = e.next()) {
2705 if (e.sym.kind == MTH &&
2706 (e.sym.flags() & (PUBLIC | PROTECTED)) != 0 &&
2707 types.overrideEquivalent(m.type, e.sym.type))
2708 log.error(pos, "intf.annotation.member.clash", e.sym, sup);
2709 }
2710 }
2711 }
2712
2713 /** Check the annotations of a symbol.
2714 */
2715 public void validateAnnotations(List<JCAnnotation> annotations, Symbol s) {
2716 for (JCAnnotation a : annotations)
2717 validateAnnotation(a, s);
2718 }
2719
2720 /** Check the type annotations.
2721 */
2722 public void validateTypeAnnotations(List<JCAnnotation> annotations, boolean isTypeParameter) {
2723 for (JCAnnotation a : annotations)
2724 validateTypeAnnotation(a, isTypeParameter);
2725 }
2726
2727 /** Check an annotation of a symbol.
2728 */
2729 private void validateAnnotation(JCAnnotation a, Symbol s) {
2730 validateAnnotationTree(a);
2731
2732 if (!annotationApplicable(a, s))
2733 log.error(a.pos(), "annotation.type.not.applicable");
2734
2735 if (a.annotationType.type.tsym == syms.functionalInterfaceType.tsym) {
2736 if (s.kind != TYP) {
2737 log.error(a.pos(), "bad.functional.intf.anno");
2738 } else if (!s.isInterface() || (s.flags() & ANNOTATION) != 0) {
2739 log.error(a.pos(), "bad.functional.intf.anno.1", diags.fragment("not.a.functional.intf", s));
2740 }
2741 }
2742 }
2743
2744 public void validateTypeAnnotation(JCAnnotation a, boolean isTypeParameter) {
2745 Assert.checkNonNull(a.type, "annotation tree hasn't been attributed yet: " + a);
2746 validateAnnotationTree(a);
2747
2748 if (a.hasTag(TYPE_ANNOTATION) &&
2749 !a.annotationType.type.isErroneous() &&
2750 !isTypeAnnotation(a, isTypeParameter)) {
2751 log.error(a.pos(), "annotation.type.not.applicable");
2752 }
2753 }
2754
2755 /**
2756 * Validate the proposed container 'repeatable' on the
2757 * annotation type symbol 's'. Report errors at position
2758 * 'pos'.
2759 *
2760 * @param s The (annotation)type declaration annotated with a @Repeatable
2761 * @param repeatable the @Repeatable on 's'
2762 * @param pos where to report errors
2763 */
2764 public void validateRepeatable(TypeSymbol s, Attribute.Compound repeatable, DiagnosticPosition pos) {
2765 Assert.check(types.isSameType(repeatable.type, syms.repeatableType));
2766
2767 Type t = null;
2768 List<Pair<MethodSymbol,Attribute>> l = repeatable.values;
2769 if (!l.isEmpty()) {
2770 Assert.check(l.head.fst.name == names.value);
2771 t = ((Attribute.Class)l.head.snd).getValue();
2772 }
2773
2774 if (t == null) {
2775 // errors should already have been reported during Annotate
2776 return;
2777 }
2778
2779 validateValue(t.tsym, s, pos);
2780 validateRetention(t.tsym, s, pos);
2781 validateDocumented(t.tsym, s, pos);
2782 validateInherited(t.tsym, s, pos);
2783 validateTarget(t.tsym, s, pos);
2784 validateDefault(t.tsym, pos);
2785 }
2786
2787 private void validateValue(TypeSymbol container, TypeSymbol contained, DiagnosticPosition pos) {
2788 Scope.Entry e = container.members().lookup(names.value);
2789 if (e.scope != null && e.sym.kind == MTH) {
2790 MethodSymbol m = (MethodSymbol) e.sym;
2791 Type ret = m.getReturnType();
2792 if (!(ret.hasTag(ARRAY) && types.isSameType(((ArrayType)ret).elemtype, contained.type))) {
2793 log.error(pos, "invalid.repeatable.annotation.value.return",
2794 container, ret, types.makeArrayType(contained.type));
2795 }
2796 } else {
2797 log.error(pos, "invalid.repeatable.annotation.no.value", container);
2798 }
2799 }
2800
2801 private void validateRetention(Symbol container, Symbol contained, DiagnosticPosition pos) {
2802 Attribute.RetentionPolicy containerRetention = types.getRetention(container);
2803 Attribute.RetentionPolicy containedRetention = types.getRetention(contained);
2804
2805 boolean error = false;
2806 switch (containedRetention) {
2807 case RUNTIME:
2808 if (containerRetention != Attribute.RetentionPolicy.RUNTIME) {
2809 error = true;
2810 }
2811 break;
2812 case CLASS:
2813 if (containerRetention == Attribute.RetentionPolicy.SOURCE) {
2814 error = true;
2815 }
2816 }
2817 if (error ) {
2818 log.error(pos, "invalid.repeatable.annotation.retention",
2819 container, containerRetention,
2820 contained, containedRetention);
2821 }
2822 }
2823
2824 private void validateDocumented(Symbol container, Symbol contained, DiagnosticPosition pos) {
2825 if (contained.attribute(syms.documentedType.tsym) != null) {
2826 if (container.attribute(syms.documentedType.tsym) == null) {
2827 log.error(pos, "invalid.repeatable.annotation.not.documented", container, contained);
2828 }
2829 }
2830 }
2831
2832 private void validateInherited(Symbol container, Symbol contained, DiagnosticPosition pos) {
2833 if (contained.attribute(syms.inheritedType.tsym) != null) {
2834 if (container.attribute(syms.inheritedType.tsym) == null) {
2835 log.error(pos, "invalid.repeatable.annotation.not.inherited", container, contained);
2836 }
2837 }
2838 }
2839
2840 private void validateTarget(Symbol container, Symbol contained, DiagnosticPosition pos) {
2841 // The set of targets the container is applicable to must be a subset
2842 // (with respect to annotation target semantics) of the set of targets
2843 // the contained is applicable to. The target sets may be implicit or
2844 // explicit.
2845
2846 Set<Name> containerTargets;
2847 Attribute.Array containerTarget = getAttributeTargetAttribute(container);
2848 if (containerTarget == null) {
2849 containerTargets = getDefaultTargetSet();
2850 } else {
2851 containerTargets = new HashSet<Name>();
2852 for (Attribute app : containerTarget.values) {
2853 if (!(app instanceof Attribute.Enum)) {
2854 continue; // recovery
2855 }
2856 Attribute.Enum e = (Attribute.Enum)app;
2857 containerTargets.add(e.value.name);
2858 }
2859 }
2860
2861 Set<Name> containedTargets;
2862 Attribute.Array containedTarget = getAttributeTargetAttribute(contained);
2863 if (containedTarget == null) {
2864 containedTargets = getDefaultTargetSet();
2865 } else {
2866 containedTargets = new HashSet<Name>();
2867 for (Attribute app : containedTarget.values) {
2868 if (!(app instanceof Attribute.Enum)) {
2869 continue; // recovery
2870 }
2871 Attribute.Enum e = (Attribute.Enum)app;
2872 containedTargets.add(e.value.name);
2873 }
2874 }
2875
2876 if (!isTargetSubsetOf(containerTargets, containedTargets)) {
2877 log.error(pos, "invalid.repeatable.annotation.incompatible.target", container, contained);
2878 }
2879 }
2880
2881 /* get a set of names for the default target */
2882 private Set<Name> getDefaultTargetSet() {
2883 if (defaultTargets == null) {
2884 Set<Name> targets = new HashSet<Name>();
2885 targets.add(names.ANNOTATION_TYPE);
2886 targets.add(names.CONSTRUCTOR);
2887 targets.add(names.FIELD);
2888 targets.add(names.LOCAL_VARIABLE);
2889 targets.add(names.METHOD);
2890 targets.add(names.PACKAGE);
2891 targets.add(names.PARAMETER);
2892 targets.add(names.TYPE);
2893
2894 defaultTargets = java.util.Collections.unmodifiableSet(targets);
2895 }
2896
2897 return defaultTargets;
2898 }
2899 private Set<Name> defaultTargets;
2900
2901
2902 /** Checks that s is a subset of t, with respect to ElementType
2903 * semantics, specifically {ANNOTATION_TYPE} is a subset of {TYPE},
2904 * and {TYPE_USE} covers the set {ANNOTATION_TYPE, TYPE, TYPE_USE,
2905 * TYPE_PARAMETER}.
2906 */
2907 private boolean isTargetSubsetOf(Set<Name> s, Set<Name> t) {
2908 // Check that all elements in s are present in t
2909 for (Name n2 : s) {
2910 boolean currentElementOk = false;
2911 for (Name n1 : t) {
2912 if (n1 == n2) {
2913 currentElementOk = true;
2914 break;
2915 } else if (n1 == names.TYPE && n2 == names.ANNOTATION_TYPE) {
2916 currentElementOk = true;
2917 break;
2918 } else if (n1 == names.TYPE_USE &&
2919 (n2 == names.TYPE ||
2920 n2 == names.ANNOTATION_TYPE ||
2921 n2 == names.TYPE_PARAMETER)) {
2922 currentElementOk = true;
2923 break;
2924 }
2925 }
2926 if (!currentElementOk)
2927 return false;
2928 }
2929 return true;
2930 }
2931
2932 private void validateDefault(Symbol container, DiagnosticPosition pos) {
2933 // validate that all other elements of containing type has defaults
2934 Scope scope = container.members();
2935 for(Symbol elm : scope.getElements()) {
2936 if (elm.name != names.value &&
2937 elm.kind == Kinds.MTH &&
2938 ((MethodSymbol)elm).defaultValue == null) {
2939 log.error(pos,
2940 "invalid.repeatable.annotation.elem.nondefault",
2941 container,
2942 elm);
2943 }
2944 }
2945 }
2946
2947 /** Is s a method symbol that overrides a method in a superclass? */
2948 boolean isOverrider(Symbol s) {
2949 if (s.kind != MTH || s.isStatic())
2950 return false;
2951 MethodSymbol m = (MethodSymbol)s;
2952 TypeSymbol owner = (TypeSymbol)m.owner;
2953 for (Type sup : types.closure(owner.type)) {
2954 if (sup == owner.type)
2955 continue; // skip "this"
2956 Scope scope = sup.tsym.members();
2957 for (Scope.Entry e = scope.lookup(m.name); e.scope != null; e = e.next()) {
2958 if (!e.sym.isStatic() && m.overrides(e.sym, owner, types, true))
2959 return true;
2960 }
2961 }
2962 return false;
2963 }
2964
2965 /** Is the annotation applicable to types? */
2966 protected boolean isTypeAnnotation(JCAnnotation a, boolean isTypeParameter) {
2967 Attribute.Compound atTarget =
2968 a.annotationType.type.tsym.attribute(syms.annotationTargetType.tsym);
2969 if (atTarget == null) {
2970 // An annotation without @Target is not a type annotation.
2971 return false;
2972 }
2973
2974 Attribute atValue = atTarget.member(names.value);
2975 if (!(atValue instanceof Attribute.Array)) {
2976 return false; // error recovery
2977 }
2978
2979 Attribute.Array arr = (Attribute.Array) atValue;
2980 for (Attribute app : arr.values) {
2981 if (!(app instanceof Attribute.Enum)) {
2982 return false; // recovery
2983 }
2984 Attribute.Enum e = (Attribute.Enum) app;
2985
2986 if (e.value.name == names.TYPE_USE)
2987 return true;
2988 else if (isTypeParameter && e.value.name == names.TYPE_PARAMETER)
2989 return true;
2990 }
2991 return false;
2992 }
2993
2994 /** Is the annotation applicable to the symbol? */
2995 boolean annotationApplicable(JCAnnotation a, Symbol s) {
2996 Attribute.Array arr = getAttributeTargetAttribute(a.annotationType.type.tsym);
2997 Name[] targets;
2998
2999 if (arr == null) {
3000 targets = defaultTargetMetaInfo(a, s);
3001 } else {
3002 // TODO: can we optimize this?
3003 targets = new Name[arr.values.length];
3004 for (int i=0; i<arr.values.length; ++i) {
3005 Attribute app = arr.values[i];
3006 if (!(app instanceof Attribute.Enum)) {
3007 return true; // recovery
3008 }
3009 Attribute.Enum e = (Attribute.Enum) app;
3010 targets[i] = e.value.name;
3011 }
3012 }
3013 for (Name target : targets) {
3014 if (target == names.TYPE)
3015 { if (s.kind == TYP) return true; }
3016 else if (target == names.FIELD)
3017 { if (s.kind == VAR && s.owner.kind != MTH) return true; }
3018 else if (target == names.METHOD)
3019 { if (s.kind == MTH && !s.isConstructor()) return true; }
3020 else if (target == names.PARAMETER)
3021 { if (s.kind == VAR &&
3022 s.owner.kind == MTH &&
3023 (s.flags() & PARAMETER) != 0)
3024 return true;
3025 }
3026 else if (target == names.CONSTRUCTOR)
3027 { if (s.kind == MTH && s.isConstructor()) return true; }
3028 else if (target == names.LOCAL_VARIABLE)
3029 { if (s.kind == VAR && s.owner.kind == MTH &&
3030 (s.flags() & PARAMETER) == 0)
3031 return true;
3032 }
3033 else if (target == names.ANNOTATION_TYPE)
3034 { if (s.kind == TYP && (s.flags() & ANNOTATION) != 0)
3035 return true;
3036 }
3037 else if (target == names.PACKAGE)
3038 { if (s.kind == PCK) return true; }
3039 else if (target == names.TYPE_USE)
3040 { if (s.kind == TYP ||
3041 s.kind == VAR ||
3042 (s.kind == MTH && !s.isConstructor() &&
3043 !s.type.getReturnType().hasTag(VOID)) ||
3044 (s.kind == MTH && s.isConstructor()))
3045 return true;
3046 }
3047 else if (target == names.TYPE_PARAMETER)
3048 { if (s.kind == TYP && s.type.hasTag(TYPEVAR))
3049 return true;
3050 }
3051 else
3052 return true; // recovery
3053 }
3054 return false;
3055 }
3056
3057
3058 Attribute.Array getAttributeTargetAttribute(Symbol s) {
3059 Attribute.Compound atTarget =
3060 s.attribute(syms.annotationTargetType.tsym);
3061 if (atTarget == null) return null; // ok, is applicable
3062 Attribute atValue = atTarget.member(names.value);
3063 if (!(atValue instanceof Attribute.Array)) return null; // error recovery
3064 return (Attribute.Array) atValue;
3065 }
3066
3067 private final Name[] dfltTargetMeta;
3068 private Name[] defaultTargetMetaInfo(JCAnnotation a, Symbol s) {
3069 return dfltTargetMeta;
3070 }
3071
3072 /** Check an annotation value.
3073 *
3074 * @param a The annotation tree to check
3075 * @return true if this annotation tree is valid, otherwise false
3076 */
3077 public boolean validateAnnotationDeferErrors(JCAnnotation a) {
3078 boolean res = false;
3079 final Log.DiagnosticHandler diagHandler = new Log.DiscardDiagnosticHandler(log);
3080 try {
3081 res = validateAnnotation(a);
3082 } finally {
3083 log.popDiagnosticHandler(diagHandler);
3084 }
3085 return res;
3086 }
3087
3088 private boolean validateAnnotation(JCAnnotation a) {
3089 boolean isValid = true;
3090 // collect an inventory of the annotation elements
3091 Set<MethodSymbol> members = new LinkedHashSet<MethodSymbol>();
3092 for (Scope.Entry e = a.annotationType.type.tsym.members().elems;
3093 e != null;
3094 e = e.sibling)
3095 if (e.sym.kind == MTH && e.sym.name != names.clinit &&
3096 (e.sym.flags() & SYNTHETIC) == 0)
3097 members.add((MethodSymbol) e.sym);
3098
3099 // remove the ones that are assigned values
3100 for (JCTree arg : a.args) {
3101 if (!arg.hasTag(ASSIGN)) continue; // recovery
3102 JCAssign assign = (JCAssign) arg;
3103 Symbol m = TreeInfo.symbol(assign.lhs);
3104 if (m == null || m.type.isErroneous()) continue;
3105 if (!members.remove(m)) {
3106 isValid = false;
3107 log.error(assign.lhs.pos(), "duplicate.annotation.member.value",
3108 m.name, a.type);
3109 }
3110 }
3111
3112 // all the remaining ones better have default values
3113 List<Name> missingDefaults = List.nil();
3114 for (MethodSymbol m : members) {
3115 if (m.defaultValue == null && !m.type.isErroneous()) {
3116 missingDefaults = missingDefaults.append(m.name);
3117 }
3118 }
3119 missingDefaults = missingDefaults.reverse();
3120 if (missingDefaults.nonEmpty()) {
3121 isValid = false;
3122 String key = (missingDefaults.size() > 1)
3123 ? "annotation.missing.default.value.1"
3124 : "annotation.missing.default.value";
3125 log.error(a.pos(), key, a.type, missingDefaults);
3126 }
3127
3128 // special case: java.lang.annotation.Target must not have
3129 // repeated values in its value member
3130 if (a.annotationType.type.tsym != syms.annotationTargetType.tsym ||
3131 a.args.tail == null)
3132 return isValid;
3133
3134 if (!a.args.head.hasTag(ASSIGN)) return false; // error recovery
3135 JCAssign assign = (JCAssign) a.args.head;
3136 Symbol m = TreeInfo.symbol(assign.lhs);
3137 if (m.name != names.value) return false;
3138 JCTree rhs = assign.rhs;
3139 if (!rhs.hasTag(NEWARRAY)) return false;
3140 JCNewArray na = (JCNewArray) rhs;
3141 Set<Symbol> targets = new HashSet<Symbol>();
3142 for (JCTree elem : na.elems) {
3143 if (!targets.add(TreeInfo.symbol(elem))) {
3144 isValid = false;
3145 log.error(elem.pos(), "repeated.annotation.target");
3146 }
3147 }
3148 return isValid;
3149 }
3150
3151 void checkDeprecatedAnnotation(DiagnosticPosition pos, Symbol s) {
3152 if (allowAnnotations &&
3153 lint.isEnabled(LintCategory.DEP_ANN) &&
3154 (s.flags() & DEPRECATED) != 0 &&
3155 !syms.deprecatedType.isErroneous() &&
3156 s.attribute(syms.deprecatedType.tsym) == null) {
3157 log.warning(LintCategory.DEP_ANN,
3158 pos, "missing.deprecated.annotation");
3159 }
3160 }
3161
3162 void checkDeprecated(final DiagnosticPosition pos, final Symbol other, final Symbol s) {
3163 if ((s.flags() & DEPRECATED) != 0 &&
3164 (other.flags() & DEPRECATED) == 0 &&
3165 s.outermostClass() != other.outermostClass()) {
3166 deferredLintHandler.report(new DeferredLintHandler.LintLogger() {
3167 @Override
3168 public void report() {
3169 warnDeprecated(pos, s);
3170 }
3171 });
3172 }
3173 }
3174
3175 void checkSunAPI(final DiagnosticPosition pos, final Symbol s) {
3176 if ((s.flags() & PROPRIETARY) != 0) {
3177 deferredLintHandler.report(new DeferredLintHandler.LintLogger() {
3178 public void report() {
3179 if (enableSunApiLintControl)
3180 warnSunApi(pos, "sun.proprietary", s);
3181 else
3182 log.mandatoryWarning(pos, "sun.proprietary", s);
3183 }
3184 });
3185 }
3186 }
3187
3188 void checkProfile(final DiagnosticPosition pos, final Symbol s) {
3189 if (profile != Profile.DEFAULT && (s.flags() & NOT_IN_PROFILE) != 0) {
3190 log.error(pos, "not.in.profile", s, profile);
3191 }
3192 }
3193
3194 /* *************************************************************************
3195 * Check for recursive annotation elements.
3196 **************************************************************************/
3197
3198 /** Check for cycles in the graph of annotation elements.
3199 */
3200 void checkNonCyclicElements(JCClassDecl tree) {
3201 if ((tree.sym.flags_field & ANNOTATION) == 0) return;
3202 Assert.check((tree.sym.flags_field & LOCKED) == 0);
3203 try {
3204 tree.sym.flags_field |= LOCKED;
3205 for (JCTree def : tree.defs) {
3206 if (!def.hasTag(METHODDEF)) continue;
3207 JCMethodDecl meth = (JCMethodDecl)def;
3208 checkAnnotationResType(meth.pos(), meth.restype.type);
3209 }
3210 } finally {
3211 tree.sym.flags_field &= ~LOCKED;
3212 tree.sym.flags_field |= ACYCLIC_ANN;
3213 }
3214 }
3215
3216 void checkNonCyclicElementsInternal(DiagnosticPosition pos, TypeSymbol tsym) {
3217 if ((tsym.flags_field & ACYCLIC_ANN) != 0)
3218 return;
3219 if ((tsym.flags_field & LOCKED) != 0) {
3220 log.error(pos, "cyclic.annotation.element");
3221 return;
3222 }
3223 try {
3224 tsym.flags_field |= LOCKED;
3225 for (Scope.Entry e = tsym.members().elems; e != null; e = e.sibling) {
3226 Symbol s = e.sym;
3227 if (s.kind != Kinds.MTH)
3228 continue;
3229 checkAnnotationResType(pos, ((MethodSymbol)s).type.getReturnType());
3230 }
3231 } finally {
3232 tsym.flags_field &= ~LOCKED;
3233 tsym.flags_field |= ACYCLIC_ANN;
3234 }
3235 }
3236
3237 void checkAnnotationResType(DiagnosticPosition pos, Type type) {
3238 switch (type.getTag()) {
3239 case CLASS:
3240 if ((type.tsym.flags() & ANNOTATION) != 0)
3241 checkNonCyclicElementsInternal(pos, type.tsym);
3242 break;
3243 case ARRAY:
3244 checkAnnotationResType(pos, types.elemtype(type));
3245 break;
3246 default:
3247 break; // int etc
3248 }
3249 }
3250
3251 /* *************************************************************************
3252 * Check for cycles in the constructor call graph.
3253 **************************************************************************/
3254
3255 /** Check for cycles in the graph of constructors calling other
3256 * constructors.
3257 */
3258 void checkCyclicConstructors(JCClassDecl tree) {
3259 Map<Symbol,Symbol> callMap = new HashMap<Symbol, Symbol>();
3260
3261 // enter each constructor this-call into the map
3262 for (List<JCTree> l = tree.defs; l.nonEmpty(); l = l.tail) {
3263 JCMethodInvocation app = TreeInfo.firstConstructorCall(l.head);
3264 if (app == null) continue;
3265 JCMethodDecl meth = (JCMethodDecl) l.head;
3266 if (TreeInfo.name(app.meth) == names._this) {
3267 callMap.put(meth.sym, TreeInfo.symbol(app.meth));
3268 } else {
3269 meth.sym.flags_field |= ACYCLIC;
3270 }
3271 }
3272
3273 // Check for cycles in the map
3274 Symbol[] ctors = new Symbol[0];
3275 ctors = callMap.keySet().toArray(ctors);
3276 for (Symbol caller : ctors) {
3277 checkCyclicConstructor(tree, caller, callMap);
3278 }
3279 }
3280
3281 /** Look in the map to see if the given constructor is part of a
3282 * call cycle.
3283 */
3284 private void checkCyclicConstructor(JCClassDecl tree, Symbol ctor,
3285 Map<Symbol,Symbol> callMap) {
3286 if (ctor != null && (ctor.flags_field & ACYCLIC) == 0) {
3287 if ((ctor.flags_field & LOCKED) != 0) {
3288 log.error(TreeInfo.diagnosticPositionFor(ctor, tree),
3289 "recursive.ctor.invocation");
3290 } else {
3291 ctor.flags_field |= LOCKED;
3292 checkCyclicConstructor(tree, callMap.remove(ctor), callMap);
3293 ctor.flags_field &= ~LOCKED;
3294 }
3295 ctor.flags_field |= ACYCLIC;
3296 }
3297 }
3298
3299 /* *************************************************************************
3300 * Miscellaneous
3301 **************************************************************************/
3302
3303 /**
3304 * Return the opcode of the operator but emit an error if it is an
3305 * error.
3306 * @param pos position for error reporting.
3307 * @param operator an operator
3308 * @param tag a tree tag
3309 * @param left type of left hand side
3310 * @param right type of right hand side
3311 */
3312 int checkOperator(DiagnosticPosition pos,
3313 OperatorSymbol operator,
3314 JCTree.Tag tag,
3315 Type left,
3316 Type right) {
3317 if (operator.opcode == ByteCodes.error) {
3318 log.error(pos,
3319 "operator.cant.be.applied.1",
3320 treeinfo.operatorName(tag),
3321 left, right);
3322 }
3323 return operator.opcode;
3324 }
3325
3326
3327 /**
3328 * Check for division by integer constant zero
3329 * @param pos Position for error reporting.
3330 * @param operator The operator for the expression
3331 * @param operand The right hand operand for the expression
3332 */
3333 void checkDivZero(DiagnosticPosition pos, Symbol operator, Type operand) {
3334 if (operand.constValue() != null
3335 && lint.isEnabled(LintCategory.DIVZERO)
3336 && operand.getTag().isSubRangeOf(LONG)
3337 && ((Number) (operand.constValue())).longValue() == 0) {
3338 int opc = ((OperatorSymbol)operator).opcode;
3339 if (opc == ByteCodes.idiv || opc == ByteCodes.imod
3340 || opc == ByteCodes.ldiv || opc == ByteCodes.lmod) {
3341 log.warning(LintCategory.DIVZERO, pos, "div.zero");
3342 }
3343 }
3344 }
3345
3346 /**
3347 * Check for empty statements after if
3348 */
3349 void checkEmptyIf(JCIf tree) {
3350 if (tree.thenpart.hasTag(SKIP) && tree.elsepart == null &&
3351 lint.isEnabled(LintCategory.EMPTY))
3352 log.warning(LintCategory.EMPTY, tree.thenpart.pos(), "empty.if");
3353 }
3354
3355 /** Check that symbol is unique in given scope.
3356 * @param pos Position for error reporting.
3357 * @param sym The symbol.
3358 * @param s The scope.
3359 */
3360 boolean checkUnique(DiagnosticPosition pos, Symbol sym, Scope s) {
3361 if (sym.type.isErroneous())
3362 return true;
3363 if (sym.owner.name == names.any) return false;
3364 for (Scope.Entry e = s.lookup(sym.name); e.scope == s; e = e.next()) {
3365 if (sym != e.sym &&
3366 (e.sym.flags() & CLASH) == 0 &&
3367 sym.kind == e.sym.kind &&
3368 sym.name != names.error &&
3369 (sym.kind != MTH ||
3370 types.hasSameArgs(sym.type, e.sym.type) ||
3371 types.hasSameArgs(types.erasure(sym.type), types.erasure(e.sym.type)))) {
3372 if ((sym.flags() & VARARGS) != (e.sym.flags() & VARARGS)) {
3373 varargsDuplicateError(pos, sym, e.sym);
3374 return true;
3375 } else if (sym.kind == MTH && !types.hasSameArgs(sym.type, e.sym.type, false)) {
3376 duplicateErasureError(pos, sym, e.sym);
3377 sym.flags_field |= CLASH;
3378 return true;
3379 } else {
3380 duplicateError(pos, e.sym);
3381 return false;
3382 }
3383 }
3384 }
3385 return true;
3386 }
3387
3388 /** Report duplicate declaration error.
3389 */
3390 void duplicateErasureError(DiagnosticPosition pos, Symbol sym1, Symbol sym2) {
3391 if (!sym1.type.isErroneous() && !sym2.type.isErroneous()) {
3392 log.error(pos, "name.clash.same.erasure", sym1, sym2);
3393 }
3394 }
3395
3396 /** Check that single-type import is not already imported or top-level defined,
3397 * but make an exception for two single-type imports which denote the same type.
3398 * @param pos Position for error reporting.
3399 * @param sym The symbol.
3400 * @param s The scope
3401 */
3402 boolean checkUniqueImport(DiagnosticPosition pos, Symbol sym, Scope s) {
3403 return checkUniqueImport(pos, sym, s, false);
3404 }
3405
3406 /** Check that static single-type import is not already imported or top-level defined,
3407 * but make an exception for two single-type imports which denote the same type.
3408 * @param pos Position for error reporting.
3409 * @param sym The symbol.
3410 * @param s The scope
3411 */
3412 boolean checkUniqueStaticImport(DiagnosticPosition pos, Symbol sym, Scope s) {
3413 return checkUniqueImport(pos, sym, s, true);
3414 }
3415
3416 /** Check that single-type import is not already imported or top-level defined,
3417 * but make an exception for two single-type imports which denote the same type.
3418 * @param pos Position for error reporting.
3419 * @param sym The symbol.
3420 * @param s The scope.
3421 * @param staticImport Whether or not this was a static import
3422 */
3423 private boolean checkUniqueImport(DiagnosticPosition pos, Symbol sym, Scope s, boolean staticImport) {
3424 for (Scope.Entry e = s.lookup(sym.name); e.scope != null; e = e.next()) {
3425 // is encountered class entered via a class declaration?
3426 boolean isClassDecl = e.scope == s;
3427 if ((isClassDecl || sym != e.sym) &&
3428 sym.kind == e.sym.kind &&
3429 sym.name != names.error &&
3430 (!staticImport || !e.isStaticallyImported())) {
3431 if (!e.sym.type.isErroneous()) {
3432 if (!isClassDecl) {
3433 if (staticImport)
3434 log.error(pos, "already.defined.static.single.import", e.sym);
3435 else
3436 log.error(pos, "already.defined.single.import", e.sym);
3437 }
3438 else if (sym != e.sym)
3439 log.error(pos, "already.defined.this.unit", e.sym);
3440 }
3441 return false;
3442 }
3443 }
3444 return true;
3445 }
3446
3447 /** Check that a qualified name is in canonical form (for import decls).
3448 */
3449 public void checkCanonical(JCTree tree) {
3450 if (!isCanonical(tree))
3451 log.error(tree.pos(), "import.requires.canonical",
3452 TreeInfo.symbol(tree));
3453 }
3454 // where
3455 private boolean isCanonical(JCTree tree) {
3456 while (tree.hasTag(SELECT)) {
3457 JCFieldAccess s = (JCFieldAccess) tree;
3458 if (s.sym.owner != TreeInfo.symbol(s.selected))
3459 return false;
3460 tree = s.selected;
3461 }
3462 return true;
3463 }
3464
3465 /** Check that an auxiliary class is not accessed from any other file than its own.
3466 */
3467 void checkForBadAuxiliaryClassAccess(DiagnosticPosition pos, Env<AttrContext> env, ClassSymbol c) {
3468 if (lint.isEnabled(Lint.LintCategory.AUXILIARYCLASS) &&
3469 (c.flags() & AUXILIARY) != 0 &&
3470 rs.isAccessible(env, c) &&
3471 !fileManager.isSameFile(c.sourcefile, env.toplevel.sourcefile))
3472 {
3473 log.warning(pos, "auxiliary.class.accessed.from.outside.of.its.source.file",
3474 c, c.sourcefile);
3475 }
3476 }
3477
3478 private class ConversionWarner extends Warner {
3479 final String uncheckedKey;
3480 final Type found;
3481 final Type expected;
3482 public ConversionWarner(DiagnosticPosition pos, String uncheckedKey, Type found, Type expected) {
3483 super(pos);
3484 this.uncheckedKey = uncheckedKey;
3485 this.found = found;
3486 this.expected = expected;
3487 }
3488
3489 @Override
3490 public void warn(LintCategory lint) {
3491 boolean warned = this.warned;
3492 super.warn(lint);
3493 if (warned) return; // suppress redundant diagnostics
3494 switch (lint) {
3495 case UNCHECKED:
3496 Check.this.warnUnchecked(pos(), "prob.found.req", diags.fragment(uncheckedKey), found, expected);
3497 break;
3498 case VARARGS:
3499 if (method != null &&
3500 method.attribute(syms.trustMeType.tsym) != null &&
3501 isTrustMeAllowedOnMethod(method) &&
3502 !types.isReifiable(method.type.getParameterTypes().last())) {
3503 Check.this.warnUnsafeVararg(pos(), "varargs.unsafe.use.varargs.param", method.params.last());
3504 }
3505 break;
3506 default:
3507 throw new AssertionError("Unexpected lint: " + lint);
3508 }
3509 }
3510 }
3511
3512 public Warner castWarner(DiagnosticPosition pos, Type found, Type expected) {
3513 return new ConversionWarner(pos, "unchecked.cast.to.type", found, expected);
3514 }
3515
3516 public Warner convertWarner(DiagnosticPosition pos, Type found, Type expected) {
3517 return new ConversionWarner(pos, "unchecked.assign", found, expected);
3518 }
3519
3520 public void checkFunctionalInterface(JCClassDecl tree, ClassSymbol cs) {
3521 Compound functionalType = cs.attribute(syms.functionalInterfaceType.tsym);
3522
3523 if (functionalType != null) {
3524 try {
3525 types.findDescriptorSymbol((TypeSymbol)cs);
3526 } catch (Types.FunctionDescriptorLookupError ex) {
3527 DiagnosticPosition pos = tree.pos();
3528 for (JCAnnotation a : tree.getModifiers().annotations) {
3529 if (a.annotationType.type.tsym == syms.functionalInterfaceType.tsym) {
3530 pos = a.pos();
3531 break;
3532 }
3533 }
3534 log.error(pos, "bad.functional.intf.anno.1", ex.getDiagnostic());
3535 }
3536 }
3537 }
3538 }