1 /*
2 * Copyright (c) 1999, 2016, 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.comp.Annotate.AnnotationTypeMetadata;
35 import com.sun.tools.javac.jvm.*;
36 import com.sun.tools.javac.resources.CompilerProperties.Errors;
37 import com.sun.tools.javac.resources.CompilerProperties.Fragments;
38 import com.sun.tools.javac.tree.*;
39 import com.sun.tools.javac.util.*;
40 import com.sun.tools.javac.util.JCDiagnostic.DiagnosticFlag;
41 import com.sun.tools.javac.util.JCDiagnostic.DiagnosticPosition;
42 import com.sun.tools.javac.util.List;
43
44 import com.sun.tools.javac.code.Lint;
45 import com.sun.tools.javac.code.Lint.LintCategory;
46 import com.sun.tools.javac.code.Scope.WriteableScope;
47 import com.sun.tools.javac.code.Type.*;
48 import com.sun.tools.javac.code.Symbol.*;
49 import com.sun.tools.javac.comp.DeferredAttr.DeferredAttrContext;
50 import com.sun.tools.javac.comp.Infer.FreeTypeListener;
51 import com.sun.tools.javac.tree.JCTree.*;
52
53 import static com.sun.tools.javac.code.Flags.*;
54 import static com.sun.tools.javac.code.Flags.ANNOTATION;
55 import static com.sun.tools.javac.code.Flags.SYNCHRONIZED;
56 import static com.sun.tools.javac.code.Kinds.*;
57 import static com.sun.tools.javac.code.Kinds.Kind.*;
58 import static com.sun.tools.javac.code.Scope.LookupKind.NON_RECURSIVE;
59 import static com.sun.tools.javac.code.TypeTag.*;
60 import static com.sun.tools.javac.code.TypeTag.WILDCARD;
61
62 import static com.sun.tools.javac.tree.JCTree.Tag.*;
63
64 /** Type checking helper class for the attribution phase.
65 *
66 * <p><b>This is NOT part of any supported API.
67 * If you write code that depends on this, you do so at your own risk.
68 * This code and its internal interfaces are subject to change or
69 * deletion without notice.</b>
70 */
71 public class Check {
72 protected static final Context.Key<Check> checkKey = new Context.Key<>();
73
74 private final Names names;
75 private final Log log;
76 private final Resolve rs;
77 private final Symtab syms;
78 private final Enter enter;
79 private final DeferredAttr deferredAttr;
80 private final Infer infer;
81 private final Types types;
82 private final TypeAnnotations typeAnnotations;
83 private final JCDiagnostic.Factory diags;
84 private final JavaFileManager fileManager;
85 private final Source source;
86 private final Profile profile;
87 private final boolean warnOnAccessToSensitiveMembers;
88
89 // The set of lint options currently in effect. It is initialized
90 // from the context, and then is set/reset as needed by Attr as it
91 // visits all the various parts of the trees during attribution.
92 private Lint lint;
93
94 // The method being analyzed in Attr - it is set/reset as needed by
95 // Attr as it visits new method declarations.
96 private MethodSymbol method;
97
98 public static Check instance(Context context) {
99 Check instance = context.get(checkKey);
100 if (instance == null)
101 instance = new Check(context);
102 return instance;
103 }
104
105 protected Check(Context context) {
106 context.put(checkKey, this);
107
108 names = Names.instance(context);
109 dfltTargetMeta = new Name[] { names.PACKAGE, names.TYPE,
110 names.FIELD, names.METHOD, names.CONSTRUCTOR,
111 names.ANNOTATION_TYPE, names.LOCAL_VARIABLE, names.PARAMETER};
112 log = Log.instance(context);
113 rs = Resolve.instance(context);
114 syms = Symtab.instance(context);
115 enter = Enter.instance(context);
116 deferredAttr = DeferredAttr.instance(context);
117 infer = Infer.instance(context);
118 types = Types.instance(context);
119 typeAnnotations = TypeAnnotations.instance(context);
120 diags = JCDiagnostic.Factory.instance(context);
121 Options options = Options.instance(context);
122 lint = Lint.instance(context);
123 fileManager = context.get(JavaFileManager.class);
124
125 source = Source.instance(context);
126 allowSimplifiedVarargs = source.allowSimplifiedVarargs();
127 allowDefaultMethods = source.allowDefaultMethods();
128 allowStrictMethodClashCheck = source.allowStrictMethodClashCheck();
129 allowPrivateSafeVarargs = source.allowPrivateSafeVarargs();
130 allowDiamondWithAnonymousClassCreation = source.allowDiamondWithAnonymousClassCreation();
131 warnOnAccessToSensitiveMembers = options.isSet("warnOnAccessToSensitiveMembers");
132
133 Target target = Target.instance(context);
134 syntheticNameChar = target.syntheticNameChar();
135
136 profile = Profile.instance(context);
137
138 boolean verboseDeprecated = lint.isEnabled(LintCategory.DEPRECATION);
139 boolean verboseUnchecked = lint.isEnabled(LintCategory.UNCHECKED);
140 boolean enforceMandatoryWarnings = true;
141
142 deprecationHandler = new MandatoryWarningHandler(log, verboseDeprecated,
143 enforceMandatoryWarnings, "deprecated", LintCategory.DEPRECATION);
144 uncheckedHandler = new MandatoryWarningHandler(log, verboseUnchecked,
145 enforceMandatoryWarnings, "unchecked", LintCategory.UNCHECKED);
146 sunApiHandler = new MandatoryWarningHandler(log, false,
147 enforceMandatoryWarnings, "sunapi", null);
148
149 deferredLintHandler = DeferredLintHandler.instance(context);
150 }
151
152 /** Switch: simplified varargs enabled?
153 */
154 boolean allowSimplifiedVarargs;
155
156 /** Switch: default methods enabled?
157 */
158 boolean allowDefaultMethods;
159
160 /** Switch: should unrelated return types trigger a method clash?
161 */
162 boolean allowStrictMethodClashCheck;
163
164 /** Switch: can the @SafeVarargs annotation be applied to private methods?
165 */
166 boolean allowPrivateSafeVarargs;
167
168 /** Switch: can diamond inference be used in anonymous instance creation ?
169 */
170 boolean allowDiamondWithAnonymousClassCreation;
171
172 /** Character for synthetic names
173 */
174 char syntheticNameChar;
175
176 /** A table mapping flat names of all compiled classes for each module in this run
177 * to their symbols; maintained from outside.
178 */
179 private Map<Pair<ModuleSymbol, Name>,ClassSymbol> compiled = new HashMap<>();
180
181 /** A handler for messages about deprecated usage.
182 */
183 private MandatoryWarningHandler deprecationHandler;
184
185 /** A handler for messages about unchecked or unsafe usage.
186 */
187 private MandatoryWarningHandler uncheckedHandler;
188
189 /** A handler for messages about using proprietary API.
190 */
191 private MandatoryWarningHandler sunApiHandler;
192
193 /** A handler for deferred lint warnings.
194 */
195 private DeferredLintHandler deferredLintHandler;
196
197 /* *************************************************************************
198 * Errors and Warnings
199 **************************************************************************/
200
201 Lint setLint(Lint newLint) {
202 Lint prev = lint;
203 lint = newLint;
204 return prev;
205 }
206
207 MethodSymbol setMethod(MethodSymbol newMethod) {
208 MethodSymbol prev = method;
209 method = newMethod;
210 return prev;
211 }
212
213 /** Warn about deprecated symbol.
214 * @param pos Position to be used for error reporting.
215 * @param sym The deprecated symbol.
216 */
217 void warnDeprecated(DiagnosticPosition pos, Symbol sym) {
218 if (!lint.isSuppressed(LintCategory.DEPRECATION))
219 deprecationHandler.report(pos, "has.been.deprecated", sym, sym.location());
220 }
221
222 /** Warn about unchecked operation.
223 * @param pos Position to be used for error reporting.
224 * @param msg A string describing the problem.
225 */
226 public void warnUnchecked(DiagnosticPosition pos, String msg, Object... args) {
227 if (!lint.isSuppressed(LintCategory.UNCHECKED))
228 uncheckedHandler.report(pos, msg, args);
229 }
230
231 /** Warn about unsafe vararg method decl.
232 * @param pos Position to be used for error reporting.
233 */
234 void warnUnsafeVararg(DiagnosticPosition pos, String key, Object... args) {
235 if (lint.isEnabled(LintCategory.VARARGS) && allowSimplifiedVarargs)
236 log.warning(LintCategory.VARARGS, pos, key, args);
237 }
238
239 public void warnStatic(DiagnosticPosition pos, String msg, Object... args) {
240 if (lint.isEnabled(LintCategory.STATIC))
241 log.warning(LintCategory.STATIC, pos, msg, args);
242 }
243
244 /** Warn about division by integer constant zero.
245 * @param pos Position to be used for error reporting.
246 */
247 void warnDivZero(DiagnosticPosition pos) {
248 if (lint.isEnabled(LintCategory.DIVZERO))
249 log.warning(LintCategory.DIVZERO, pos, "div.zero");
250 }
251
252 /**
253 * Report any deferred diagnostics.
254 */
255 public void reportDeferredDiagnostics() {
256 deprecationHandler.reportDeferredDiagnostic();
257 uncheckedHandler.reportDeferredDiagnostic();
258 sunApiHandler.reportDeferredDiagnostic();
259 }
260
261
262 /** Report a failure to complete a class.
263 * @param pos Position to be used for error reporting.
264 * @param ex The failure to report.
265 */
266 public Type completionError(DiagnosticPosition pos, CompletionFailure ex) {
267 log.error(JCDiagnostic.DiagnosticFlag.NON_DEFERRABLE, pos, "cant.access", ex.sym, ex.getDetailValue());
268 if (ex instanceof ClassFinder.BadClassFile) throw new Abort();
269 else return syms.errType;
270 }
271
272 /** Report an error that wrong type tag was found.
273 * @param pos Position to be used for error reporting.
274 * @param required An internationalized string describing the type tag
275 * required.
276 * @param found The type that was found.
277 */
278 Type typeTagError(DiagnosticPosition pos, Object required, Object found) {
279 // this error used to be raised by the parser,
280 // but has been delayed to this point:
281 if (found instanceof Type && ((Type)found).hasTag(VOID)) {
282 log.error(pos, "illegal.start.of.type");
283 return syms.errType;
284 }
285 log.error(pos, "type.found.req", found, required);
286 return types.createErrorType(found instanceof Type ? (Type)found : syms.errType);
287 }
288
289 /** Report an error that symbol cannot be referenced before super
290 * has been called.
291 * @param pos Position to be used for error reporting.
292 * @param sym The referenced symbol.
293 */
294 void earlyRefError(DiagnosticPosition pos, Symbol sym) {
295 log.error(pos, "cant.ref.before.ctor.called", sym);
296 }
297
298 /** Report duplicate declaration error.
299 */
300 void duplicateError(DiagnosticPosition pos, Symbol sym) {
301 if (!sym.type.isErroneous()) {
302 Symbol location = sym.location();
303 if (location.kind == MTH &&
304 ((MethodSymbol)location).isStaticOrInstanceInit()) {
305 log.error(pos, "already.defined.in.clinit", kindName(sym), sym,
306 kindName(sym.location()), kindName(sym.location().enclClass()),
307 sym.location().enclClass());
308 } else {
309 log.error(pos, "already.defined", kindName(sym), sym,
310 kindName(sym.location()), sym.location());
311 }
312 }
313 }
314
315 /** Report array/varargs duplicate declaration
316 */
317 void varargsDuplicateError(DiagnosticPosition pos, Symbol sym1, Symbol sym2) {
318 if (!sym1.type.isErroneous() && !sym2.type.isErroneous()) {
319 log.error(pos, "array.and.varargs", sym1, sym2, sym2.location());
320 }
321 }
322
323 /* ************************************************************************
324 * duplicate declaration checking
325 *************************************************************************/
326
327 /** Check that variable does not hide variable with same name in
328 * immediately enclosing local scope.
329 * @param pos Position for error reporting.
330 * @param v The symbol.
331 * @param s The scope.
332 */
333 void checkTransparentVar(DiagnosticPosition pos, VarSymbol v, Scope s) {
334 for (Symbol sym : s.getSymbolsByName(v.name)) {
335 if (sym.owner != v.owner) break;
336 if (sym.kind == VAR &&
337 sym.owner.kind.matches(KindSelector.VAL_MTH) &&
338 v.name != names.error) {
339 duplicateError(pos, sym);
340 return;
341 }
342 }
343 }
344
345 /** Check that a class or interface does not hide a class or
346 * interface with same name in immediately enclosing local scope.
347 * @param pos Position for error reporting.
348 * @param c The symbol.
349 * @param s The scope.
350 */
351 void checkTransparentClass(DiagnosticPosition pos, ClassSymbol c, Scope s) {
352 for (Symbol sym : s.getSymbolsByName(c.name)) {
353 if (sym.owner != c.owner) break;
354 if (sym.kind == TYP && !sym.type.hasTag(TYPEVAR) &&
355 sym.owner.kind.matches(KindSelector.VAL_MTH) &&
356 c.name != names.error) {
357 duplicateError(pos, sym);
358 return;
359 }
360 }
361 }
362
363 /** Check that class does not have the same name as one of
364 * its enclosing classes, or as a class defined in its enclosing scope.
365 * return true if class is unique in its enclosing scope.
366 * @param pos Position for error reporting.
367 * @param name The class name.
368 * @param s The enclosing scope.
369 */
370 boolean checkUniqueClassName(DiagnosticPosition pos, Name name, Scope s) {
371 for (Symbol sym : s.getSymbolsByName(name, NON_RECURSIVE)) {
372 if (sym.kind == TYP && sym.name != names.error) {
373 duplicateError(pos, sym);
374 return false;
375 }
376 }
377 for (Symbol sym = s.owner; sym != null; sym = sym.owner) {
378 if (sym.kind == TYP && sym.name == name && sym.name != names.error) {
379 duplicateError(pos, sym);
380 return true;
381 }
382 }
383 return true;
384 }
385
386 /* *************************************************************************
387 * Class name generation
388 **************************************************************************/
389
390
391 private Map<Pair<Name, Name>, Integer> localClassNameIndexes = new HashMap<>();
392
393 /** Return name of local class.
394 * This is of the form {@code <enclClass> $ n <classname> }
395 * where
396 * enclClass is the flat name of the enclosing class,
397 * classname is the simple name of the local class
398 */
399 Name localClassName(ClassSymbol c) {
400 Name enclFlatname = c.owner.enclClass().flatname;
401 String enclFlatnameStr = enclFlatname.toString();
402 Pair<Name, Name> key = new Pair<>(enclFlatname, c.name);
403 Integer index = localClassNameIndexes.get(key);
404 for (int i = (index == null) ? 1 : index; ; i++) {
405 Name flatname = names.fromString(enclFlatnameStr
406 + syntheticNameChar + i + c.name);
407 if (getCompiled(c.packge().modle, flatname) == null) {
408 localClassNameIndexes.put(key, i + 1);
409 return flatname;
410 }
411 }
412 }
413
414 void clearLocalClassNameIndexes(ClassSymbol c) {
415 localClassNameIndexes.remove(new Pair<>(
416 c.owner.enclClass().flatname, c.name));
417 }
418
419 public void newRound() {
420 compiled.clear();
421 localClassNameIndexes.clear();
422 }
423
424 public void putCompiled(ClassSymbol csym) {
425 compiled.put(Pair.of(csym.packge().modle, csym.flatname), csym);
426 }
427
428 public ClassSymbol getCompiled(ClassSymbol csym) {
429 return compiled.get(Pair.of(csym.packge().modle, csym.flatname));
430 }
431
432 public ClassSymbol getCompiled(ModuleSymbol msym, Name flatname) {
433 return compiled.get(Pair.of(msym, flatname));
434 }
435
436 public void removeCompiled(ClassSymbol csym) {
437 compiled.remove(Pair.of(csym.packge().modle, csym.flatname));
438 }
439
440 /* *************************************************************************
441 * Type Checking
442 **************************************************************************/
443
444 /**
445 * A check context is an object that can be used to perform compatibility
446 * checks - depending on the check context, meaning of 'compatibility' might
447 * vary significantly.
448 */
449 public interface CheckContext {
450 /**
451 * Is type 'found' compatible with type 'req' in given context
452 */
453 boolean compatible(Type found, Type req, Warner warn);
454 /**
455 * Report a check error
456 */
457 void report(DiagnosticPosition pos, JCDiagnostic details);
458 /**
459 * Obtain a warner for this check context
460 */
461 public Warner checkWarner(DiagnosticPosition pos, Type found, Type req);
462
463 public InferenceContext inferenceContext();
464
465 public DeferredAttr.DeferredAttrContext deferredAttrContext();
466 }
467
468 /**
469 * This class represent a check context that is nested within another check
470 * context - useful to check sub-expressions. The default behavior simply
471 * redirects all method calls to the enclosing check context leveraging
472 * the forwarding pattern.
473 */
474 static class NestedCheckContext implements CheckContext {
475 CheckContext enclosingContext;
476
477 NestedCheckContext(CheckContext enclosingContext) {
478 this.enclosingContext = enclosingContext;
479 }
480
481 public boolean compatible(Type found, Type req, Warner warn) {
482 return enclosingContext.compatible(found, req, warn);
483 }
484
485 public void report(DiagnosticPosition pos, JCDiagnostic details) {
486 enclosingContext.report(pos, details);
487 }
488
489 public Warner checkWarner(DiagnosticPosition pos, Type found, Type req) {
490 return enclosingContext.checkWarner(pos, found, req);
491 }
492
493 public InferenceContext inferenceContext() {
494 return enclosingContext.inferenceContext();
495 }
496
497 public DeferredAttrContext deferredAttrContext() {
498 return enclosingContext.deferredAttrContext();
499 }
500 }
501
502 /**
503 * Check context to be used when evaluating assignment/return statements
504 */
505 CheckContext basicHandler = new CheckContext() {
506 public void report(DiagnosticPosition pos, JCDiagnostic details) {
507 log.error(pos, "prob.found.req", details);
508 }
509 public boolean compatible(Type found, Type req, Warner warn) {
510 return types.isAssignable(found, req, warn);
511 }
512
513 public Warner checkWarner(DiagnosticPosition pos, Type found, Type req) {
514 return convertWarner(pos, found, req);
515 }
516
517 public InferenceContext inferenceContext() {
518 return infer.emptyContext;
519 }
520
521 public DeferredAttrContext deferredAttrContext() {
522 return deferredAttr.emptyDeferredAttrContext;
523 }
524
525 @Override
526 public String toString() {
527 return "CheckContext: basicHandler";
528 }
529 };
530
531 /** Check that a given type is assignable to a given proto-type.
532 * If it is, return the type, otherwise return errType.
533 * @param pos Position to be used for error reporting.
534 * @param found The type that was found.
535 * @param req The type that was required.
536 */
537 public Type checkType(DiagnosticPosition pos, Type found, Type req) {
538 return checkType(pos, found, req, basicHandler);
539 }
540
541 Type checkType(final DiagnosticPosition pos, final Type found, final Type req, final CheckContext checkContext) {
542 final InferenceContext inferenceContext = checkContext.inferenceContext();
543 if (inferenceContext.free(req) || inferenceContext.free(found)) {
544 inferenceContext.addFreeTypeListener(List.of(req, found), new FreeTypeListener() {
545 @Override
546 public void typesInferred(InferenceContext inferenceContext) {
547 checkType(pos, inferenceContext.asInstType(found), inferenceContext.asInstType(req), checkContext);
548 }
549 });
550 }
551 if (req.hasTag(ERROR))
552 return req;
553 if (req.hasTag(NONE))
554 return found;
555 if (checkContext.compatible(found, req, checkContext.checkWarner(pos, found, req))) {
556 return found;
557 } else {
558 if (found.isNumeric() && req.isNumeric()) {
559 checkContext.report(pos, diags.fragment("possible.loss.of.precision", found, req));
560 return types.createErrorType(found);
561 }
562 checkContext.report(pos, diags.fragment("inconvertible.types", found, req));
563 return types.createErrorType(found);
564 }
565 }
566
567 /** Check that a given type can be cast to a given target type.
568 * Return the result of the cast.
569 * @param pos Position to be used for error reporting.
570 * @param found The type that is being cast.
571 * @param req The target type of the cast.
572 */
573 Type checkCastable(DiagnosticPosition pos, Type found, Type req) {
574 return checkCastable(pos, found, req, basicHandler);
575 }
576 Type checkCastable(DiagnosticPosition pos, Type found, Type req, CheckContext checkContext) {
577 if (types.isCastable(found, req, castWarner(pos, found, req))) {
578 return req;
579 } else {
580 checkContext.report(pos, diags.fragment("inconvertible.types", found, req));
581 return types.createErrorType(found);
582 }
583 }
584
585 /** Check for redundant casts (i.e. where source type is a subtype of target type)
586 * The problem should only be reported for non-292 cast
587 */
588 public void checkRedundantCast(Env<AttrContext> env, final JCTypeCast tree) {
589 if (!tree.type.isErroneous()
590 && types.isSameType(tree.expr.type, tree.clazz.type)
591 && !(ignoreAnnotatedCasts && TreeInfo.containsTypeAnnotation(tree.clazz))
592 && !is292targetTypeCast(tree)) {
593 deferredLintHandler.report(new DeferredLintHandler.LintLogger() {
594 @Override
595 public void report() {
596 if (lint.isEnabled(Lint.LintCategory.CAST))
597 log.warning(Lint.LintCategory.CAST,
598 tree.pos(), "redundant.cast", tree.clazz.type);
599 }
600 });
601 }
602 }
603 //where
604 private boolean is292targetTypeCast(JCTypeCast tree) {
605 boolean is292targetTypeCast = false;
606 JCExpression expr = TreeInfo.skipParens(tree.expr);
607 if (expr.hasTag(APPLY)) {
608 JCMethodInvocation apply = (JCMethodInvocation)expr;
609 Symbol sym = TreeInfo.symbol(apply.meth);
610 is292targetTypeCast = sym != null &&
611 sym.kind == MTH &&
612 (sym.flags() & HYPOTHETICAL) != 0;
613 }
614 return is292targetTypeCast;
615 }
616
617 private static final boolean ignoreAnnotatedCasts = true;
618
619 /** Check that a type is within some bounds.
620 *
621 * Used in TypeApply to verify that, e.g., X in {@code V<X>} is a valid
622 * type argument.
623 * @param a The type that should be bounded by bs.
624 * @param bound The bound.
625 */
626 private boolean checkExtends(Type a, Type bound) {
627 if (a.isUnbound()) {
628 return true;
629 } else if (!a.hasTag(WILDCARD)) {
630 a = types.cvarUpperBound(a);
631 return types.isSubtype(a, bound);
632 } else if (a.isExtendsBound()) {
633 return types.isCastable(bound, types.wildUpperBound(a), types.noWarnings);
634 } else if (a.isSuperBound()) {
635 return !types.notSoftSubtype(types.wildLowerBound(a), bound);
636 }
637 return true;
638 }
639
640 /** Check that type is different from 'void'.
641 * @param pos Position to be used for error reporting.
642 * @param t The type to be checked.
643 */
644 Type checkNonVoid(DiagnosticPosition pos, Type t) {
645 if (t.hasTag(VOID)) {
646 log.error(pos, "void.not.allowed.here");
647 return types.createErrorType(t);
648 } else {
649 return t;
650 }
651 }
652
653 Type checkClassOrArrayType(DiagnosticPosition pos, Type t) {
654 if (!t.hasTag(CLASS) && !t.hasTag(ARRAY) && !t.hasTag(ERROR)) {
655 return typeTagError(pos,
656 diags.fragment("type.req.class.array"),
657 asTypeParam(t));
658 } else {
659 return t;
660 }
661 }
662
663 /** Check that type is a class or interface type.
664 * @param pos Position to be used for error reporting.
665 * @param t The type to be checked.
666 */
667 Type checkClassType(DiagnosticPosition pos, Type t) {
668 if (!t.hasTag(CLASS) && !t.hasTag(ERROR)) {
669 return typeTagError(pos,
670 diags.fragment("type.req.class"),
671 asTypeParam(t));
672 } else {
673 return t;
674 }
675 }
676 //where
677 private Object asTypeParam(Type t) {
678 return (t.hasTag(TYPEVAR))
679 ? diags.fragment("type.parameter", t)
680 : t;
681 }
682
683 /** Check that type is a valid qualifier for a constructor reference expression
684 */
685 Type checkConstructorRefType(DiagnosticPosition pos, Type t) {
686 t = checkClassOrArrayType(pos, t);
687 if (t.hasTag(CLASS)) {
688 if ((t.tsym.flags() & (ABSTRACT | INTERFACE)) != 0) {
689 log.error(pos, "abstract.cant.be.instantiated", t.tsym);
690 t = types.createErrorType(t);
691 } else if ((t.tsym.flags() & ENUM) != 0) {
692 log.error(pos, "enum.cant.be.instantiated");
693 t = types.createErrorType(t);
694 } else {
695 t = checkClassType(pos, t, true);
696 }
697 } else if (t.hasTag(ARRAY)) {
698 if (!types.isReifiable(((ArrayType)t).elemtype)) {
699 log.error(pos, "generic.array.creation");
700 t = types.createErrorType(t);
701 }
702 }
703 return t;
704 }
705
706 /** Check that type is a class or interface type.
707 * @param pos Position to be used for error reporting.
708 * @param t The type to be checked.
709 * @param noBounds True if type bounds are illegal here.
710 */
711 Type checkClassType(DiagnosticPosition pos, Type t, boolean noBounds) {
712 t = checkClassType(pos, t);
713 if (noBounds && t.isParameterized()) {
714 List<Type> args = t.getTypeArguments();
715 while (args.nonEmpty()) {
716 if (args.head.hasTag(WILDCARD))
717 return typeTagError(pos,
718 diags.fragment("type.req.exact"),
719 args.head);
720 args = args.tail;
721 }
722 }
723 return t;
724 }
725
726 /** Check that type is a reference type, i.e. a class, interface or array type
727 * or a type variable.
728 * @param pos Position to be used for error reporting.
729 * @param t The type to be checked.
730 */
731 Type checkRefType(DiagnosticPosition pos, Type t) {
732 if (t.isReference())
733 return t;
734 else
735 return typeTagError(pos,
736 diags.fragment("type.req.ref"),
737 t);
738 }
739
740 /** Check that each type is a reference type, i.e. a class, interface or array type
741 * or a type variable.
742 * @param trees Original trees, used for error reporting.
743 * @param types The types to be checked.
744 */
745 List<Type> checkRefTypes(List<JCExpression> trees, List<Type> types) {
746 List<JCExpression> tl = trees;
747 for (List<Type> l = types; l.nonEmpty(); l = l.tail) {
748 l.head = checkRefType(tl.head.pos(), l.head);
749 tl = tl.tail;
750 }
751 return types;
752 }
753
754 /** Check that type is a null or reference type.
755 * @param pos Position to be used for error reporting.
756 * @param t The type to be checked.
757 */
758 Type checkNullOrRefType(DiagnosticPosition pos, Type t) {
759 if (t.isReference() || t.hasTag(BOT))
760 return t;
761 else
762 return typeTagError(pos,
763 diags.fragment("type.req.ref"),
764 t);
765 }
766
767 /** Check that flag set does not contain elements of two conflicting sets. s
768 * Return true if it doesn't.
769 * @param pos Position to be used for error reporting.
770 * @param flags The set of flags to be checked.
771 * @param set1 Conflicting flags set #1.
772 * @param set2 Conflicting flags set #2.
773 */
774 boolean checkDisjoint(DiagnosticPosition pos, long flags, long set1, long set2) {
775 if ((flags & set1) != 0 && (flags & set2) != 0) {
776 log.error(pos,
777 "illegal.combination.of.modifiers",
778 asFlagSet(TreeInfo.firstFlag(flags & set1)),
779 asFlagSet(TreeInfo.firstFlag(flags & set2)));
780 return false;
781 } else
782 return true;
783 }
784
785 /** Check that usage of diamond operator is correct (i.e. diamond should not
786 * be used with non-generic classes or in anonymous class creation expressions)
787 */
788 Type checkDiamond(JCNewClass tree, Type t) {
789 if (!TreeInfo.isDiamond(tree) ||
790 t.isErroneous()) {
791 return checkClassType(tree.clazz.pos(), t, true);
792 } else {
793 if (tree.def != null && !allowDiamondWithAnonymousClassCreation) {
794 log.error(DiagnosticFlag.SOURCE_LEVEL, tree.clazz.pos(),
795 Errors.CantApplyDiamond1(t, Fragments.DiamondAndAnonClassNotSupportedInSource(source.name)));
796 }
797 if (t.tsym.type.getTypeArguments().isEmpty()) {
798 log.error(tree.clazz.pos(),
799 "cant.apply.diamond.1",
800 t, diags.fragment("diamond.non.generic", t));
801 return types.createErrorType(t);
802 } else if (tree.typeargs != null &&
803 tree.typeargs.nonEmpty()) {
804 log.error(tree.clazz.pos(),
805 "cant.apply.diamond.1",
806 t, diags.fragment("diamond.and.explicit.params", t));
807 return types.createErrorType(t);
808 } else {
809 return t;
810 }
811 }
812 }
813
814 /** Check that the type inferred using the diamond operator does not contain
815 * non-denotable types such as captured types or intersection types.
816 * @param t the type inferred using the diamond operator
817 * @return the (possibly empty) list of non-denotable types.
818 */
819 List<Type> checkDiamondDenotable(ClassType t) {
820 ListBuffer<Type> buf = new ListBuffer<>();
821 for (Type arg : t.allparams()) {
822 if (!diamondTypeChecker.visit(arg, null)) {
823 buf.append(arg);
824 }
825 }
826 return buf.toList();
827 }
828 // where
829
830 /** diamondTypeChecker: A type visitor that descends down the given type looking for non-denotable
831 * types. The visit methods return false as soon as a non-denotable type is encountered and true
832 * otherwise.
833 */
834 private static final Types.SimpleVisitor<Boolean, Void> diamondTypeChecker = new Types.SimpleVisitor<Boolean, Void>() {
835 @Override
836 public Boolean visitType(Type t, Void s) {
837 return true;
838 }
839 @Override
840 public Boolean visitClassType(ClassType t, Void s) {
841 if (t.isCompound()) {
842 return false;
843 }
844 for (Type targ : t.allparams()) {
845 if (!visit(targ, s)) {
846 return false;
847 }
848 }
849 return true;
850 }
851
852 @Override
853 public Boolean visitTypeVar(TypeVar t, Void s) {
854 /* Any type variable mentioned in the inferred type must have been declared as a type parameter
855 (i.e cannot have been produced by inference (18.4))
856 */
857 return t.tsym.owner.type.getTypeArguments().contains(t);
858 }
859
860 @Override
861 public Boolean visitCapturedType(CapturedType t, Void s) {
862 /* Any type variable mentioned in the inferred type must have been declared as a type parameter
863 (i.e cannot have been produced by capture conversion (5.1.10))
864 */
865 return false;
866 }
867
868 @Override
869 public Boolean visitArrayType(ArrayType t, Void s) {
870 return visit(t.elemtype, s);
871 }
872
873 @Override
874 public Boolean visitWildcardType(WildcardType t, Void s) {
875 return visit(t.type, s);
876 }
877 };
878
879 void checkVarargsMethodDecl(Env<AttrContext> env, JCMethodDecl tree) {
880 MethodSymbol m = tree.sym;
881 if (!allowSimplifiedVarargs) return;
882 boolean hasTrustMeAnno = m.attribute(syms.trustMeType.tsym) != null;
883 Type varargElemType = null;
884 if (m.isVarArgs()) {
885 varargElemType = types.elemtype(tree.params.last().type);
886 }
887 if (hasTrustMeAnno && !isTrustMeAllowedOnMethod(m)) {
888 if (varargElemType != null) {
889 log.error(tree,
890 "varargs.invalid.trustme.anno",
891 syms.trustMeType.tsym,
892 allowPrivateSafeVarargs ?
893 diags.fragment("varargs.trustme.on.virtual.varargs", m) :
894 diags.fragment("varargs.trustme.on.virtual.varargs.final.only", m));
895 } else {
896 log.error(tree,
897 "varargs.invalid.trustme.anno",
898 syms.trustMeType.tsym,
899 diags.fragment("varargs.trustme.on.non.varargs.meth", m));
900 }
901 } else if (hasTrustMeAnno && varargElemType != null &&
902 types.isReifiable(varargElemType)) {
903 warnUnsafeVararg(tree,
904 "varargs.redundant.trustme.anno",
905 syms.trustMeType.tsym,
906 diags.fragment("varargs.trustme.on.reifiable.varargs", varargElemType));
907 }
908 else if (!hasTrustMeAnno && varargElemType != null &&
909 !types.isReifiable(varargElemType)) {
910 warnUnchecked(tree.params.head.pos(), "unchecked.varargs.non.reifiable.type", varargElemType);
911 }
912 }
913 //where
914 private boolean isTrustMeAllowedOnMethod(Symbol s) {
915 return (s.flags() & VARARGS) != 0 &&
916 (s.isConstructor() ||
917 (s.flags() & (STATIC | FINAL |
918 (allowPrivateSafeVarargs ? PRIVATE : 0) )) != 0);
919 }
920
921 Type checkMethod(final Type mtype,
922 final Symbol sym,
923 final Env<AttrContext> env,
924 final List<JCExpression> argtrees,
925 final List<Type> argtypes,
926 final boolean useVarargs,
927 InferenceContext inferenceContext) {
928 // System.out.println("call : " + env.tree);
929 // System.out.println("method : " + owntype);
930 // System.out.println("actuals: " + argtypes);
931 if (inferenceContext.free(mtype)) {
932 inferenceContext.addFreeTypeListener(List.of(mtype), new FreeTypeListener() {
933 public void typesInferred(InferenceContext inferenceContext) {
934 checkMethod(inferenceContext.asInstType(mtype), sym, env, argtrees, argtypes, useVarargs, inferenceContext);
935 }
936 });
937 return mtype;
938 }
939 Type owntype = mtype;
940 List<Type> formals = owntype.getParameterTypes();
941 List<Type> nonInferred = sym.type.getParameterTypes();
942 if (nonInferred.length() != formals.length()) nonInferred = formals;
943 Type last = useVarargs ? formals.last() : null;
944 if (sym.name == names.init && sym.owner == syms.enumSym) {
945 formals = formals.tail.tail;
946 nonInferred = nonInferred.tail.tail;
947 }
948 List<JCExpression> args = argtrees;
949 if (args != null) {
950 //this is null when type-checking a method reference
951 while (formals.head != last) {
952 JCTree arg = args.head;
953 Warner warn = convertWarner(arg.pos(), arg.type, nonInferred.head);
954 assertConvertible(arg, arg.type, formals.head, warn);
955 args = args.tail;
956 formals = formals.tail;
957 nonInferred = nonInferred.tail;
958 }
959 if (useVarargs) {
960 Type varArg = types.elemtype(last);
961 while (args.tail != null) {
962 JCTree arg = args.head;
963 Warner warn = convertWarner(arg.pos(), arg.type, varArg);
964 assertConvertible(arg, arg.type, varArg, warn);
965 args = args.tail;
966 }
967 } else if ((sym.flags() & (VARARGS | SIGNATURE_POLYMORPHIC)) == VARARGS) {
968 // non-varargs call to varargs method
969 Type varParam = owntype.getParameterTypes().last();
970 Type lastArg = argtypes.last();
971 if (types.isSubtypeUnchecked(lastArg, types.elemtype(varParam)) &&
972 !types.isSameType(types.erasure(varParam), types.erasure(lastArg)))
973 log.warning(argtrees.last().pos(), "inexact.non-varargs.call",
974 types.elemtype(varParam), varParam);
975 }
976 }
977 if (useVarargs) {
978 Type argtype = owntype.getParameterTypes().last();
979 if (!types.isReifiable(argtype) &&
980 (!allowSimplifiedVarargs ||
981 sym.baseSymbol().attribute(syms.trustMeType.tsym) == null ||
982 !isTrustMeAllowedOnMethod(sym))) {
983 warnUnchecked(env.tree.pos(),
984 "unchecked.generic.array.creation",
985 argtype);
986 }
987 if ((sym.baseSymbol().flags() & SIGNATURE_POLYMORPHIC) == 0) {
988 TreeInfo.setVarargsElement(env.tree, types.elemtype(argtype));
989 }
990 }
991 return owntype;
992 }
993 //where
994 private void assertConvertible(JCTree tree, Type actual, Type formal, Warner warn) {
995 if (types.isConvertible(actual, formal, warn))
996 return;
997
998 if (formal.isCompound()
999 && types.isSubtype(actual, types.supertype(formal))
1000 && types.isSubtypeUnchecked(actual, types.interfaces(formal), warn))
1001 return;
1002 }
1003
1004 /**
1005 * Check that type 't' is a valid instantiation of a generic class
1006 * (see JLS 4.5)
1007 *
1008 * @param t class type to be checked
1009 * @return true if 't' is well-formed
1010 */
1011 public boolean checkValidGenericType(Type t) {
1012 return firstIncompatibleTypeArg(t) == null;
1013 }
1014 //WHERE
1015 private Type firstIncompatibleTypeArg(Type type) {
1016 List<Type> formals = type.tsym.type.allparams();
1017 List<Type> actuals = type.allparams();
1018 List<Type> args = type.getTypeArguments();
1019 List<Type> forms = type.tsym.type.getTypeArguments();
1020 ListBuffer<Type> bounds_buf = new ListBuffer<>();
1021
1022 // For matching pairs of actual argument types `a' and
1023 // formal type parameters with declared bound `b' ...
1024 while (args.nonEmpty() && forms.nonEmpty()) {
1025 // exact type arguments needs to know their
1026 // bounds (for upper and lower bound
1027 // calculations). So we create new bounds where
1028 // type-parameters are replaced with actuals argument types.
1029 bounds_buf.append(types.subst(forms.head.getUpperBound(), formals, actuals));
1030 args = args.tail;
1031 forms = forms.tail;
1032 }
1033
1034 args = type.getTypeArguments();
1035 List<Type> tvars_cap = types.substBounds(formals,
1036 formals,
1037 types.capture(type).allparams());
1038 while (args.nonEmpty() && tvars_cap.nonEmpty()) {
1039 // Let the actual arguments know their bound
1040 args.head.withTypeVar((TypeVar)tvars_cap.head);
1041 args = args.tail;
1042 tvars_cap = tvars_cap.tail;
1043 }
1044
1045 args = type.getTypeArguments();
1046 List<Type> bounds = bounds_buf.toList();
1047
1048 while (args.nonEmpty() && bounds.nonEmpty()) {
1049 Type actual = args.head;
1050 if (!isTypeArgErroneous(actual) &&
1051 !bounds.head.isErroneous() &&
1052 !checkExtends(actual, bounds.head)) {
1053 return args.head;
1054 }
1055 args = args.tail;
1056 bounds = bounds.tail;
1057 }
1058
1059 args = type.getTypeArguments();
1060 bounds = bounds_buf.toList();
1061
1062 for (Type arg : types.capture(type).getTypeArguments()) {
1063 if (arg.hasTag(TYPEVAR) &&
1064 arg.getUpperBound().isErroneous() &&
1065 !bounds.head.isErroneous() &&
1066 !isTypeArgErroneous(args.head)) {
1067 return args.head;
1068 }
1069 bounds = bounds.tail;
1070 args = args.tail;
1071 }
1072
1073 return null;
1074 }
1075 //where
1076 boolean isTypeArgErroneous(Type t) {
1077 return isTypeArgErroneous.visit(t);
1078 }
1079
1080 Types.UnaryVisitor<Boolean> isTypeArgErroneous = new Types.UnaryVisitor<Boolean>() {
1081 public Boolean visitType(Type t, Void s) {
1082 return t.isErroneous();
1083 }
1084 @Override
1085 public Boolean visitTypeVar(TypeVar t, Void s) {
1086 return visit(t.getUpperBound());
1087 }
1088 @Override
1089 public Boolean visitCapturedType(CapturedType t, Void s) {
1090 return visit(t.getUpperBound()) ||
1091 visit(t.getLowerBound());
1092 }
1093 @Override
1094 public Boolean visitWildcardType(WildcardType t, Void s) {
1095 return visit(t.type);
1096 }
1097 };
1098
1099 /** Check that given modifiers are legal for given symbol and
1100 * return modifiers together with any implicit modifiers for that symbol.
1101 * Warning: we can't use flags() here since this method
1102 * is called during class enter, when flags() would cause a premature
1103 * completion.
1104 * @param pos Position to be used for error reporting.
1105 * @param flags The set of modifiers given in a definition.
1106 * @param sym The defined symbol.
1107 */
1108 long checkFlags(DiagnosticPosition pos, long flags, Symbol sym, JCTree tree) {
1109 long mask;
1110 long implicit = 0;
1111
1112 switch (sym.kind) {
1113 case VAR:
1114 if (TreeInfo.isReceiverParam(tree))
1115 mask = ReceiverParamFlags;
1116 else if (sym.owner.kind != TYP)
1117 mask = LocalVarFlags;
1118 else if ((sym.owner.flags_field & INTERFACE) != 0)
1119 mask = implicit = InterfaceVarFlags;
1120 else
1121 mask = VarFlags;
1122 break;
1123 case MTH:
1124 if (sym.name == names.init) {
1125 if ((sym.owner.flags_field & ENUM) != 0) {
1126 // enum constructors cannot be declared public or
1127 // protected and must be implicitly or explicitly
1128 // private
1129 implicit = PRIVATE;
1130 mask = PRIVATE;
1131 } else
1132 mask = ConstructorFlags;
1133 } else if ((sym.owner.flags_field & INTERFACE) != 0) {
1134 if ((sym.owner.flags_field & ANNOTATION) != 0) {
1135 mask = AnnotationTypeElementMask;
1136 implicit = PUBLIC | ABSTRACT;
1137 } else if ((flags & (DEFAULT | STATIC | PRIVATE)) != 0) {
1138 mask = InterfaceMethodMask;
1139 implicit = (flags & PRIVATE) != 0 ? 0 : PUBLIC;
1140 if ((flags & DEFAULT) != 0) {
1141 implicit |= ABSTRACT;
1142 }
1143 } else {
1144 mask = implicit = InterfaceMethodFlags;
1145 }
1146 } else {
1147 mask = MethodFlags;
1148 }
1149 // Imply STRICTFP if owner has STRICTFP set.
1150 if (((flags|implicit) & Flags.ABSTRACT) == 0 ||
1151 ((flags) & Flags.DEFAULT) != 0)
1152 implicit |= sym.owner.flags_field & STRICTFP;
1153 break;
1154 case TYP:
1155 if (sym.isLocal()) {
1156 mask = LocalClassFlags;
1157 if ((sym.owner.flags_field & STATIC) == 0 &&
1158 (flags & ENUM) != 0)
1159 log.error(pos, "enums.must.be.static");
1160 } else if (sym.owner.kind == TYP) {
1161 mask = MemberClassFlags;
1162 if (sym.owner.owner.kind == PCK ||
1163 (sym.owner.flags_field & STATIC) != 0)
1164 mask |= STATIC;
1165 else if ((flags & ENUM) != 0)
1166 log.error(pos, "enums.must.be.static");
1167 // Nested interfaces and enums are always STATIC (Spec ???)
1168 if ((flags & (INTERFACE | ENUM)) != 0 ) implicit = STATIC;
1169 } else {
1170 mask = ClassFlags;
1171 }
1172 // Interfaces are always ABSTRACT
1173 if ((flags & INTERFACE) != 0) implicit |= ABSTRACT;
1174
1175 if ((flags & ENUM) != 0) {
1176 // enums can't be declared abstract or final
1177 mask &= ~(ABSTRACT | FINAL);
1178 implicit |= implicitEnumFinalFlag(tree);
1179 }
1180 // Imply STRICTFP if owner has STRICTFP set.
1181 implicit |= sym.owner.flags_field & STRICTFP;
1182 break;
1183 default:
1184 throw new AssertionError();
1185 }
1186 long illegal = flags & ExtendedStandardFlags & ~mask;
1187 if (illegal != 0) {
1188 if ((illegal & INTERFACE) != 0) {
1189 log.error(pos, "intf.not.allowed.here");
1190 mask |= INTERFACE;
1191 }
1192 else {
1193 log.error(pos,
1194 "mod.not.allowed.here", asFlagSet(illegal));
1195 }
1196 }
1197 else if ((sym.kind == TYP ||
1198 // ISSUE: Disallowing abstract&private is no longer appropriate
1199 // in the presence of inner classes. Should it be deleted here?
1200 checkDisjoint(pos, flags,
1201 ABSTRACT,
1202 PRIVATE | STATIC | DEFAULT))
1203 &&
1204 checkDisjoint(pos, flags,
1205 STATIC | PRIVATE,
1206 DEFAULT)
1207 &&
1208 checkDisjoint(pos, flags,
1209 ABSTRACT | INTERFACE,
1210 FINAL | NATIVE | SYNCHRONIZED)
1211 &&
1212 checkDisjoint(pos, flags,
1213 PUBLIC,
1214 PRIVATE | PROTECTED)
1215 &&
1216 checkDisjoint(pos, flags,
1217 PRIVATE,
1218 PUBLIC | PROTECTED)
1219 &&
1220 checkDisjoint(pos, flags,
1221 FINAL,
1222 VOLATILE)
1223 &&
1224 (sym.kind == TYP ||
1225 checkDisjoint(pos, flags,
1226 ABSTRACT | NATIVE,
1227 STRICTFP))) {
1228 // skip
1229 }
1230 return flags & (mask | ~ExtendedStandardFlags) | implicit;
1231 }
1232
1233
1234 /** Determine if this enum should be implicitly final.
1235 *
1236 * If the enum has no specialized enum contants, it is final.
1237 *
1238 * If the enum does have specialized enum contants, it is
1239 * <i>not</i> final.
1240 */
1241 private long implicitEnumFinalFlag(JCTree tree) {
1242 if (!tree.hasTag(CLASSDEF)) return 0;
1243 class SpecialTreeVisitor extends JCTree.Visitor {
1244 boolean specialized;
1245 SpecialTreeVisitor() {
1246 this.specialized = false;
1247 }
1248
1249 @Override
1250 public void visitTree(JCTree tree) { /* no-op */ }
1251
1252 @Override
1253 public void visitVarDef(JCVariableDecl tree) {
1254 if ((tree.mods.flags & ENUM) != 0) {
1255 if (tree.init instanceof JCNewClass &&
1256 ((JCNewClass) tree.init).def != null) {
1257 specialized = true;
1258 }
1259 }
1260 }
1261 }
1262
1263 SpecialTreeVisitor sts = new SpecialTreeVisitor();
1264 JCClassDecl cdef = (JCClassDecl) tree;
1265 for (JCTree defs: cdef.defs) {
1266 defs.accept(sts);
1267 if (sts.specialized) return 0;
1268 }
1269 return FINAL;
1270 }
1271
1272 /* *************************************************************************
1273 * Type Validation
1274 **************************************************************************/
1275
1276 /** Validate a type expression. That is,
1277 * check that all type arguments of a parametric type are within
1278 * their bounds. This must be done in a second phase after type attribution
1279 * since a class might have a subclass as type parameter bound. E.g:
1280 *
1281 * <pre>{@code
1282 * class B<A extends C> { ... }
1283 * class C extends B<C> { ... }
1284 * }</pre>
1285 *
1286 * and we can't make sure that the bound is already attributed because
1287 * of possible cycles.
1288 *
1289 * Visitor method: Validate a type expression, if it is not null, catching
1290 * and reporting any completion failures.
1291 */
1292 void validate(JCTree tree, Env<AttrContext> env) {
1293 validate(tree, env, true);
1294 }
1295 void validate(JCTree tree, Env<AttrContext> env, boolean checkRaw) {
1296 new Validator(env).validateTree(tree, checkRaw, true);
1297 }
1298
1299 /** Visitor method: Validate a list of type expressions.
1300 */
1301 void validate(List<? extends JCTree> trees, Env<AttrContext> env) {
1302 for (List<? extends JCTree> l = trees; l.nonEmpty(); l = l.tail)
1303 validate(l.head, env);
1304 }
1305
1306 /** A visitor class for type validation.
1307 */
1308 class Validator extends JCTree.Visitor {
1309
1310 boolean checkRaw;
1311 boolean isOuter;
1312 Env<AttrContext> env;
1313
1314 Validator(Env<AttrContext> env) {
1315 this.env = env;
1316 }
1317
1318 @Override
1319 public void visitTypeArray(JCArrayTypeTree tree) {
1320 validateTree(tree.elemtype, checkRaw, isOuter);
1321 }
1322
1323 @Override
1324 public void visitTypeApply(JCTypeApply tree) {
1325 if (tree.type.hasTag(CLASS)) {
1326 List<JCExpression> args = tree.arguments;
1327 List<Type> forms = tree.type.tsym.type.getTypeArguments();
1328
1329 Type incompatibleArg = firstIncompatibleTypeArg(tree.type);
1330 if (incompatibleArg != null) {
1331 for (JCTree arg : tree.arguments) {
1332 if (arg.type == incompatibleArg) {
1333 log.error(arg, "not.within.bounds", incompatibleArg, forms.head);
1334 }
1335 forms = forms.tail;
1336 }
1337 }
1338
1339 forms = tree.type.tsym.type.getTypeArguments();
1340
1341 boolean is_java_lang_Class = tree.type.tsym.flatName() == names.java_lang_Class;
1342
1343 // For matching pairs of actual argument types `a' and
1344 // formal type parameters with declared bound `b' ...
1345 while (args.nonEmpty() && forms.nonEmpty()) {
1346 validateTree(args.head,
1347 !(isOuter && is_java_lang_Class),
1348 false);
1349 args = args.tail;
1350 forms = forms.tail;
1351 }
1352
1353 // Check that this type is either fully parameterized, or
1354 // not parameterized at all.
1355 if (tree.type.getEnclosingType().isRaw())
1356 log.error(tree.pos(), "improperly.formed.type.inner.raw.param");
1357 if (tree.clazz.hasTag(SELECT))
1358 visitSelectInternal((JCFieldAccess)tree.clazz);
1359 }
1360 }
1361
1362 @Override
1363 public void visitTypeParameter(JCTypeParameter tree) {
1364 validateTrees(tree.bounds, true, isOuter);
1365 checkClassBounds(tree.pos(), tree.type);
1366 }
1367
1368 @Override
1369 public void visitWildcard(JCWildcard tree) {
1370 if (tree.inner != null)
1371 validateTree(tree.inner, true, isOuter);
1372 }
1373
1374 @Override
1375 public void visitSelect(JCFieldAccess tree) {
1376 if (tree.type.hasTag(CLASS)) {
1377 visitSelectInternal(tree);
1378
1379 // Check that this type is either fully parameterized, or
1380 // not parameterized at all.
1381 if (tree.selected.type.isParameterized() && tree.type.tsym.type.getTypeArguments().nonEmpty())
1382 log.error(tree.pos(), "improperly.formed.type.param.missing");
1383 }
1384 }
1385
1386 public void visitSelectInternal(JCFieldAccess tree) {
1387 if (tree.type.tsym.isStatic() &&
1388 tree.selected.type.isParameterized()) {
1389 // The enclosing type is not a class, so we are
1390 // looking at a static member type. However, the
1391 // qualifying expression is parameterized.
1392 log.error(tree.pos(), "cant.select.static.class.from.param.type");
1393 } else {
1394 // otherwise validate the rest of the expression
1395 tree.selected.accept(this);
1396 }
1397 }
1398
1399 @Override
1400 public void visitAnnotatedType(JCAnnotatedType tree) {
1401 tree.underlyingType.accept(this);
1402 }
1403
1404 @Override
1405 public void visitTypeIdent(JCPrimitiveTypeTree that) {
1406 if (that.type.hasTag(TypeTag.VOID)) {
1407 log.error(that.pos(), "void.not.allowed.here");
1408 }
1409 super.visitTypeIdent(that);
1410 }
1411
1412 /** Default visitor method: do nothing.
1413 */
1414 @Override
1415 public void visitTree(JCTree tree) {
1416 }
1417
1418 public void validateTree(JCTree tree, boolean checkRaw, boolean isOuter) {
1419 if (tree != null) {
1420 boolean prevCheckRaw = this.checkRaw;
1421 this.checkRaw = checkRaw;
1422 this.isOuter = isOuter;
1423
1424 try {
1425 tree.accept(this);
1426 if (checkRaw)
1427 checkRaw(tree, env);
1428 } catch (CompletionFailure ex) {
1429 completionError(tree.pos(), ex);
1430 } finally {
1431 this.checkRaw = prevCheckRaw;
1432 }
1433 }
1434 }
1435
1436 public void validateTrees(List<? extends JCTree> trees, boolean checkRaw, boolean isOuter) {
1437 for (List<? extends JCTree> l = trees; l.nonEmpty(); l = l.tail)
1438 validateTree(l.head, checkRaw, isOuter);
1439 }
1440 }
1441
1442 void checkRaw(JCTree tree, Env<AttrContext> env) {
1443 if (lint.isEnabled(LintCategory.RAW) &&
1444 tree.type.hasTag(CLASS) &&
1445 !TreeInfo.isDiamond(tree) &&
1446 !withinAnonConstr(env) &&
1447 tree.type.isRaw()) {
1448 log.warning(LintCategory.RAW,
1449 tree.pos(), "raw.class.use", tree.type, tree.type.tsym.type);
1450 }
1451 }
1452 //where
1453 private boolean withinAnonConstr(Env<AttrContext> env) {
1454 return env.enclClass.name.isEmpty() &&
1455 env.enclMethod != null && env.enclMethod.name == names.init;
1456 }
1457
1458 /* *************************************************************************
1459 * Exception checking
1460 **************************************************************************/
1461
1462 /* The following methods treat classes as sets that contain
1463 * the class itself and all their subclasses
1464 */
1465
1466 /** Is given type a subtype of some of the types in given list?
1467 */
1468 boolean subset(Type t, List<Type> ts) {
1469 for (List<Type> l = ts; l.nonEmpty(); l = l.tail)
1470 if (types.isSubtype(t, l.head)) return true;
1471 return false;
1472 }
1473
1474 /** Is given type a subtype or supertype of
1475 * some of the types in given list?
1476 */
1477 boolean intersects(Type t, List<Type> ts) {
1478 for (List<Type> l = ts; l.nonEmpty(); l = l.tail)
1479 if (types.isSubtype(t, l.head) || types.isSubtype(l.head, t)) return true;
1480 return false;
1481 }
1482
1483 /** Add type set to given type list, unless it is a subclass of some class
1484 * in the list.
1485 */
1486 List<Type> incl(Type t, List<Type> ts) {
1487 return subset(t, ts) ? ts : excl(t, ts).prepend(t);
1488 }
1489
1490 /** Remove type set from type set list.
1491 */
1492 List<Type> excl(Type t, List<Type> ts) {
1493 if (ts.isEmpty()) {
1494 return ts;
1495 } else {
1496 List<Type> ts1 = excl(t, ts.tail);
1497 if (types.isSubtype(ts.head, t)) return ts1;
1498 else if (ts1 == ts.tail) return ts;
1499 else return ts1.prepend(ts.head);
1500 }
1501 }
1502
1503 /** Form the union of two type set lists.
1504 */
1505 List<Type> union(List<Type> ts1, List<Type> ts2) {
1506 List<Type> ts = ts1;
1507 for (List<Type> l = ts2; l.nonEmpty(); l = l.tail)
1508 ts = incl(l.head, ts);
1509 return ts;
1510 }
1511
1512 /** Form the difference of two type lists.
1513 */
1514 List<Type> diff(List<Type> ts1, List<Type> ts2) {
1515 List<Type> ts = ts1;
1516 for (List<Type> l = ts2; l.nonEmpty(); l = l.tail)
1517 ts = excl(l.head, ts);
1518 return ts;
1519 }
1520
1521 /** Form the intersection of two type lists.
1522 */
1523 public List<Type> intersect(List<Type> ts1, List<Type> ts2) {
1524 List<Type> ts = List.nil();
1525 for (List<Type> l = ts1; l.nonEmpty(); l = l.tail)
1526 if (subset(l.head, ts2)) ts = incl(l.head, ts);
1527 for (List<Type> l = ts2; l.nonEmpty(); l = l.tail)
1528 if (subset(l.head, ts1)) ts = incl(l.head, ts);
1529 return ts;
1530 }
1531
1532 /** Is exc an exception symbol that need not be declared?
1533 */
1534 boolean isUnchecked(ClassSymbol exc) {
1535 return
1536 exc.kind == ERR ||
1537 exc.isSubClass(syms.errorType.tsym, types) ||
1538 exc.isSubClass(syms.runtimeExceptionType.tsym, types);
1539 }
1540
1541 /** Is exc an exception type that need not be declared?
1542 */
1543 boolean isUnchecked(Type exc) {
1544 return
1545 (exc.hasTag(TYPEVAR)) ? isUnchecked(types.supertype(exc)) :
1546 (exc.hasTag(CLASS)) ? isUnchecked((ClassSymbol)exc.tsym) :
1547 exc.hasTag(BOT);
1548 }
1549
1550 /** Same, but handling completion failures.
1551 */
1552 boolean isUnchecked(DiagnosticPosition pos, Type exc) {
1553 try {
1554 return isUnchecked(exc);
1555 } catch (CompletionFailure ex) {
1556 completionError(pos, ex);
1557 return true;
1558 }
1559 }
1560
1561 /** Is exc handled by given exception list?
1562 */
1563 boolean isHandled(Type exc, List<Type> handled) {
1564 return isUnchecked(exc) || subset(exc, handled);
1565 }
1566
1567 /** Return all exceptions in thrown list that are not in handled list.
1568 * @param thrown The list of thrown exceptions.
1569 * @param handled The list of handled exceptions.
1570 */
1571 List<Type> unhandled(List<Type> thrown, List<Type> handled) {
1572 List<Type> unhandled = List.nil();
1573 for (List<Type> l = thrown; l.nonEmpty(); l = l.tail)
1574 if (!isHandled(l.head, handled)) unhandled = unhandled.prepend(l.head);
1575 return unhandled;
1576 }
1577
1578 /* *************************************************************************
1579 * Overriding/Implementation checking
1580 **************************************************************************/
1581
1582 /** The level of access protection given by a flag set,
1583 * where PRIVATE is highest and PUBLIC is lowest.
1584 */
1585 static int protection(long flags) {
1586 switch ((short)(flags & AccessFlags)) {
1587 case PRIVATE: return 3;
1588 case PROTECTED: return 1;
1589 default:
1590 case PUBLIC: return 0;
1591 case 0: return 2;
1592 }
1593 }
1594
1595 /** A customized "cannot override" error message.
1596 * @param m The overriding method.
1597 * @param other The overridden method.
1598 * @return An internationalized string.
1599 */
1600 Object cannotOverride(MethodSymbol m, MethodSymbol other) {
1601 String key;
1602 if ((other.owner.flags() & INTERFACE) == 0)
1603 key = "cant.override";
1604 else if ((m.owner.flags() & INTERFACE) == 0)
1605 key = "cant.implement";
1606 else
1607 key = "clashes.with";
1608 return diags.fragment(key, m, m.location(), other, other.location());
1609 }
1610
1611 /** A customized "override" warning message.
1612 * @param m The overriding method.
1613 * @param other The overridden method.
1614 * @return An internationalized string.
1615 */
1616 Object uncheckedOverrides(MethodSymbol m, MethodSymbol other) {
1617 String key;
1618 if ((other.owner.flags() & INTERFACE) == 0)
1619 key = "unchecked.override";
1620 else if ((m.owner.flags() & INTERFACE) == 0)
1621 key = "unchecked.implement";
1622 else
1623 key = "unchecked.clash.with";
1624 return diags.fragment(key, m, m.location(), other, other.location());
1625 }
1626
1627 /** A customized "override" warning message.
1628 * @param m The overriding method.
1629 * @param other The overridden method.
1630 * @return An internationalized string.
1631 */
1632 Object varargsOverrides(MethodSymbol m, MethodSymbol other) {
1633 String key;
1634 if ((other.owner.flags() & INTERFACE) == 0)
1635 key = "varargs.override";
1636 else if ((m.owner.flags() & INTERFACE) == 0)
1637 key = "varargs.implement";
1638 else
1639 key = "varargs.clash.with";
1640 return diags.fragment(key, m, m.location(), other, other.location());
1641 }
1642
1643 /** Check that this method conforms with overridden method 'other'.
1644 * where `origin' is the class where checking started.
1645 * Complications:
1646 * (1) Do not check overriding of synthetic methods
1647 * (reason: they might be final).
1648 * todo: check whether this is still necessary.
1649 * (2) Admit the case where an interface proxy throws fewer exceptions
1650 * than the method it implements. Augment the proxy methods with the
1651 * undeclared exceptions in this case.
1652 * (3) When generics are enabled, admit the case where an interface proxy
1653 * has a result type
1654 * extended by the result type of the method it implements.
1655 * Change the proxies result type to the smaller type in this case.
1656 *
1657 * @param tree The tree from which positions
1658 * are extracted for errors.
1659 * @param m The overriding method.
1660 * @param other The overridden method.
1661 * @param origin The class of which the overriding method
1662 * is a member.
1663 */
1664 void checkOverride(JCTree tree,
1665 MethodSymbol m,
1666 MethodSymbol other,
1667 ClassSymbol origin) {
1668 // Don't check overriding of synthetic methods or by bridge methods.
1669 if ((m.flags() & (SYNTHETIC|BRIDGE)) != 0 || (other.flags() & SYNTHETIC) != 0) {
1670 return;
1671 }
1672
1673 // Error if static method overrides instance method (JLS 8.4.6.2).
1674 if ((m.flags() & STATIC) != 0 &&
1675 (other.flags() & STATIC) == 0) {
1676 log.error(TreeInfo.diagnosticPositionFor(m, tree), "override.static",
1677 cannotOverride(m, other));
1678 m.flags_field |= BAD_OVERRIDE;
1679 return;
1680 }
1681
1682 // Error if instance method overrides static or final
1683 // method (JLS 8.4.6.1).
1684 if ((other.flags() & FINAL) != 0 ||
1685 (m.flags() & STATIC) == 0 &&
1686 (other.flags() & STATIC) != 0) {
1687 log.error(TreeInfo.diagnosticPositionFor(m, tree), "override.meth",
1688 cannotOverride(m, other),
1689 asFlagSet(other.flags() & (FINAL | STATIC)));
1690 m.flags_field |= BAD_OVERRIDE;
1691 return;
1692 }
1693
1694 if ((m.owner.flags() & ANNOTATION) != 0) {
1695 // handled in validateAnnotationMethod
1696 return;
1697 }
1698
1699 // Error if overriding method has weaker access (JLS 8.4.6.3).
1700 if (protection(m.flags()) > protection(other.flags())) {
1701 log.error(TreeInfo.diagnosticPositionFor(m, tree), "override.weaker.access",
1702 cannotOverride(m, other),
1703 (other.flags() & AccessFlags) == 0 ?
1704 "package" :
1705 asFlagSet(other.flags() & AccessFlags));
1706 m.flags_field |= BAD_OVERRIDE;
1707 return;
1708 }
1709
1710 Type mt = types.memberType(origin.type, m);
1711 Type ot = types.memberType(origin.type, other);
1712 // Error if overriding result type is different
1713 // (or, in the case of generics mode, not a subtype) of
1714 // overridden result type. We have to rename any type parameters
1715 // before comparing types.
1716 List<Type> mtvars = mt.getTypeArguments();
1717 List<Type> otvars = ot.getTypeArguments();
1718 Type mtres = mt.getReturnType();
1719 Type otres = types.subst(ot.getReturnType(), otvars, mtvars);
1720
1721 overrideWarner.clear();
1722 boolean resultTypesOK =
1723 types.returnTypeSubstitutable(mt, ot, otres, overrideWarner);
1724 if (!resultTypesOK) {
1725 if ((m.flags() & STATIC) != 0 && (other.flags() & STATIC) != 0) {
1726 log.error(TreeInfo.diagnosticPositionFor(m, tree),
1727 Errors.OverrideIncompatibleRet(Fragments.CantHide(m, m.location(), other,
1728 other.location()), mtres, otres));
1729 m.flags_field |= BAD_OVERRIDE;
1730 } else {
1731 log.error(TreeInfo.diagnosticPositionFor(m, tree),
1732 "override.incompatible.ret",
1733 cannotOverride(m, other),
1734 mtres, otres);
1735 m.flags_field |= BAD_OVERRIDE;
1736 }
1737 return;
1738 } else if (overrideWarner.hasNonSilentLint(LintCategory.UNCHECKED)) {
1739 warnUnchecked(TreeInfo.diagnosticPositionFor(m, tree),
1740 "override.unchecked.ret",
1741 uncheckedOverrides(m, other),
1742 mtres, otres);
1743 }
1744
1745 // Error if overriding method throws an exception not reported
1746 // by overridden method.
1747 List<Type> otthrown = types.subst(ot.getThrownTypes(), otvars, mtvars);
1748 List<Type> unhandledErased = unhandled(mt.getThrownTypes(), types.erasure(otthrown));
1749 List<Type> unhandledUnerased = unhandled(mt.getThrownTypes(), otthrown);
1750 if (unhandledErased.nonEmpty()) {
1751 log.error(TreeInfo.diagnosticPositionFor(m, tree),
1752 "override.meth.doesnt.throw",
1753 cannotOverride(m, other),
1754 unhandledUnerased.head);
1755 m.flags_field |= BAD_OVERRIDE;
1756 return;
1757 }
1758 else if (unhandledUnerased.nonEmpty()) {
1759 warnUnchecked(TreeInfo.diagnosticPositionFor(m, tree),
1760 "override.unchecked.thrown",
1761 cannotOverride(m, other),
1762 unhandledUnerased.head);
1763 return;
1764 }
1765
1766 // Optional warning if varargs don't agree
1767 if ((((m.flags() ^ other.flags()) & Flags.VARARGS) != 0)
1768 && lint.isEnabled(LintCategory.OVERRIDES)) {
1769 log.warning(TreeInfo.diagnosticPositionFor(m, tree),
1770 ((m.flags() & Flags.VARARGS) != 0)
1771 ? "override.varargs.missing"
1772 : "override.varargs.extra",
1773 varargsOverrides(m, other));
1774 }
1775
1776 // Warn if instance method overrides bridge method (compiler spec ??)
1777 if ((other.flags() & BRIDGE) != 0) {
1778 log.warning(TreeInfo.diagnosticPositionFor(m, tree), "override.bridge",
1779 uncheckedOverrides(m, other));
1780 }
1781
1782 // Warn if a deprecated method overridden by a non-deprecated one.
1783 if (!isDeprecatedOverrideIgnorable(other, origin)) {
1784 Lint prevLint = setLint(lint.augment(m));
1785 try {
1786 checkDeprecated(TreeInfo.diagnosticPositionFor(m, tree), m, other);
1787 } finally {
1788 setLint(prevLint);
1789 }
1790 }
1791 }
1792 // where
1793 private boolean isDeprecatedOverrideIgnorable(MethodSymbol m, ClassSymbol origin) {
1794 // If the method, m, is defined in an interface, then ignore the issue if the method
1795 // is only inherited via a supertype and also implemented in the supertype,
1796 // because in that case, we will rediscover the issue when examining the method
1797 // in the supertype.
1798 // If the method, m, is not defined in an interface, then the only time we need to
1799 // address the issue is when the method is the supertype implemementation: any other
1800 // case, we will have dealt with when examining the supertype classes
1801 ClassSymbol mc = m.enclClass();
1802 Type st = types.supertype(origin.type);
1803 if (!st.hasTag(CLASS))
1804 return true;
1805 MethodSymbol stimpl = m.implementation((ClassSymbol)st.tsym, types, false);
1806
1807 if (mc != null && ((mc.flags() & INTERFACE) != 0)) {
1808 List<Type> intfs = types.interfaces(origin.type);
1809 return (intfs.contains(mc.type) ? false : (stimpl != null));
1810 }
1811 else
1812 return (stimpl != m);
1813 }
1814
1815
1816 // used to check if there were any unchecked conversions
1817 Warner overrideWarner = new Warner();
1818
1819 /** Check that a class does not inherit two concrete methods
1820 * with the same signature.
1821 * @param pos Position to be used for error reporting.
1822 * @param site The class type to be checked.
1823 */
1824 public void checkCompatibleConcretes(DiagnosticPosition pos, Type site) {
1825 Type sup = types.supertype(site);
1826 if (!sup.hasTag(CLASS)) return;
1827
1828 for (Type t1 = sup;
1829 t1.hasTag(CLASS) && t1.tsym.type.isParameterized();
1830 t1 = types.supertype(t1)) {
1831 for (Symbol s1 : t1.tsym.members().getSymbols(NON_RECURSIVE)) {
1832 if (s1.kind != MTH ||
1833 (s1.flags() & (STATIC|SYNTHETIC|BRIDGE)) != 0 ||
1834 !s1.isInheritedIn(site.tsym, types) ||
1835 ((MethodSymbol)s1).implementation(site.tsym,
1836 types,
1837 true) != s1)
1838 continue;
1839 Type st1 = types.memberType(t1, s1);
1840 int s1ArgsLength = st1.getParameterTypes().length();
1841 if (st1 == s1.type) continue;
1842
1843 for (Type t2 = sup;
1844 t2.hasTag(CLASS);
1845 t2 = types.supertype(t2)) {
1846 for (Symbol s2 : t2.tsym.members().getSymbolsByName(s1.name)) {
1847 if (s2 == s1 ||
1848 s2.kind != MTH ||
1849 (s2.flags() & (STATIC|SYNTHETIC|BRIDGE)) != 0 ||
1850 s2.type.getParameterTypes().length() != s1ArgsLength ||
1851 !s2.isInheritedIn(site.tsym, types) ||
1852 ((MethodSymbol)s2).implementation(site.tsym,
1853 types,
1854 true) != s2)
1855 continue;
1856 Type st2 = types.memberType(t2, s2);
1857 if (types.overrideEquivalent(st1, st2))
1858 log.error(pos, "concrete.inheritance.conflict",
1859 s1, t1, s2, t2, sup);
1860 }
1861 }
1862 }
1863 }
1864 }
1865
1866 /** Check that classes (or interfaces) do not each define an abstract
1867 * method with same name and arguments but incompatible return types.
1868 * @param pos Position to be used for error reporting.
1869 * @param t1 The first argument type.
1870 * @param t2 The second argument type.
1871 */
1872 public boolean checkCompatibleAbstracts(DiagnosticPosition pos,
1873 Type t1,
1874 Type t2,
1875 Type site) {
1876 if ((site.tsym.flags() & COMPOUND) != 0) {
1877 // special case for intersections: need to eliminate wildcards in supertypes
1878 t1 = types.capture(t1);
1879 t2 = types.capture(t2);
1880 }
1881 return firstIncompatibility(pos, t1, t2, site) == null;
1882 }
1883
1884 /** Return the first method which is defined with same args
1885 * but different return types in two given interfaces, or null if none
1886 * exists.
1887 * @param t1 The first type.
1888 * @param t2 The second type.
1889 * @param site The most derived type.
1890 * @returns symbol from t2 that conflicts with one in t1.
1891 */
1892 private Symbol firstIncompatibility(DiagnosticPosition pos, Type t1, Type t2, Type site) {
1893 Map<TypeSymbol,Type> interfaces1 = new HashMap<>();
1894 closure(t1, interfaces1);
1895 Map<TypeSymbol,Type> interfaces2;
1896 if (t1 == t2)
1897 interfaces2 = interfaces1;
1898 else
1899 closure(t2, interfaces1, interfaces2 = new HashMap<>());
1900
1901 for (Type t3 : interfaces1.values()) {
1902 for (Type t4 : interfaces2.values()) {
1903 Symbol s = firstDirectIncompatibility(pos, t3, t4, site);
1904 if (s != null) return s;
1905 }
1906 }
1907 return null;
1908 }
1909
1910 /** Compute all the supertypes of t, indexed by type symbol. */
1911 private void closure(Type t, Map<TypeSymbol,Type> typeMap) {
1912 if (!t.hasTag(CLASS)) return;
1913 if (typeMap.put(t.tsym, t) == null) {
1914 closure(types.supertype(t), typeMap);
1915 for (Type i : types.interfaces(t))
1916 closure(i, typeMap);
1917 }
1918 }
1919
1920 /** Compute all the supertypes of t, indexed by type symbol (except thise in typesSkip). */
1921 private void closure(Type t, Map<TypeSymbol,Type> typesSkip, Map<TypeSymbol,Type> typeMap) {
1922 if (!t.hasTag(CLASS)) return;
1923 if (typesSkip.get(t.tsym) != null) return;
1924 if (typeMap.put(t.tsym, t) == null) {
1925 closure(types.supertype(t), typesSkip, typeMap);
1926 for (Type i : types.interfaces(t))
1927 closure(i, typesSkip, typeMap);
1928 }
1929 }
1930
1931 /** Return the first method in t2 that conflicts with a method from t1. */
1932 private Symbol firstDirectIncompatibility(DiagnosticPosition pos, Type t1, Type t2, Type site) {
1933 for (Symbol s1 : t1.tsym.members().getSymbols(NON_RECURSIVE)) {
1934 Type st1 = null;
1935 if (s1.kind != MTH || !s1.isInheritedIn(site.tsym, types) ||
1936 (s1.flags() & SYNTHETIC) != 0) continue;
1937 Symbol impl = ((MethodSymbol)s1).implementation(site.tsym, types, false);
1938 if (impl != null && (impl.flags() & ABSTRACT) == 0) continue;
1939 for (Symbol s2 : t2.tsym.members().getSymbolsByName(s1.name)) {
1940 if (s1 == s2) continue;
1941 if (s2.kind != MTH || !s2.isInheritedIn(site.tsym, types) ||
1942 (s2.flags() & SYNTHETIC) != 0) continue;
1943 if (st1 == null) st1 = types.memberType(t1, s1);
1944 Type st2 = types.memberType(t2, s2);
1945 if (types.overrideEquivalent(st1, st2)) {
1946 List<Type> tvars1 = st1.getTypeArguments();
1947 List<Type> tvars2 = st2.getTypeArguments();
1948 Type rt1 = st1.getReturnType();
1949 Type rt2 = types.subst(st2.getReturnType(), tvars2, tvars1);
1950 boolean compat =
1951 types.isSameType(rt1, rt2) ||
1952 !rt1.isPrimitiveOrVoid() &&
1953 !rt2.isPrimitiveOrVoid() &&
1954 (types.covariantReturnType(rt1, rt2, types.noWarnings) ||
1955 types.covariantReturnType(rt2, rt1, types.noWarnings)) ||
1956 checkCommonOverriderIn(s1,s2,site);
1957 if (!compat) {
1958 log.error(pos, "types.incompatible.diff.ret",
1959 t1, t2, s2.name +
1960 "(" + types.memberType(t2, s2).getParameterTypes() + ")");
1961 return s2;
1962 }
1963 } else if (checkNameClash((ClassSymbol)site.tsym, s1, s2) &&
1964 !checkCommonOverriderIn(s1, s2, site)) {
1965 log.error(pos,
1966 "name.clash.same.erasure.no.override",
1967 s1, s1.location(),
1968 s2, s2.location());
1969 return s2;
1970 }
1971 }
1972 }
1973 return null;
1974 }
1975 //WHERE
1976 boolean checkCommonOverriderIn(Symbol s1, Symbol s2, Type site) {
1977 Map<TypeSymbol,Type> supertypes = new HashMap<>();
1978 Type st1 = types.memberType(site, s1);
1979 Type st2 = types.memberType(site, s2);
1980 closure(site, supertypes);
1981 for (Type t : supertypes.values()) {
1982 for (Symbol s3 : t.tsym.members().getSymbolsByName(s1.name)) {
1983 if (s3 == s1 || s3 == s2 || s3.kind != MTH || (s3.flags() & (BRIDGE|SYNTHETIC)) != 0) continue;
1984 Type st3 = types.memberType(site,s3);
1985 if (types.overrideEquivalent(st3, st1) &&
1986 types.overrideEquivalent(st3, st2) &&
1987 types.returnTypeSubstitutable(st3, st1) &&
1988 types.returnTypeSubstitutable(st3, st2)) {
1989 return true;
1990 }
1991 }
1992 }
1993 return false;
1994 }
1995
1996 /** Check that a given method conforms with any method it overrides.
1997 * @param tree The tree from which positions are extracted
1998 * for errors.
1999 * @param m The overriding method.
2000 */
2001 void checkOverride(Env<AttrContext> env, JCMethodDecl tree, MethodSymbol m) {
2002 ClassSymbol origin = (ClassSymbol)m.owner;
2003 if ((origin.flags() & ENUM) != 0 && names.finalize.equals(m.name))
2004 if (m.overrides(syms.enumFinalFinalize, origin, types, false)) {
2005 log.error(tree.pos(), "enum.no.finalize");
2006 return;
2007 }
2008 for (Type t = origin.type; t.hasTag(CLASS);
2009 t = types.supertype(t)) {
2010 if (t != origin.type) {
2011 checkOverride(tree, t, origin, m);
2012 }
2013 for (Type t2 : types.interfaces(t)) {
2014 checkOverride(tree, t2, origin, m);
2015 }
2016 }
2017
2018 final boolean explicitOverride = m.attribute(syms.overrideType.tsym) != null;
2019 // Check if this method must override a super method due to being annotated with @Override
2020 // or by virtue of being a member of a diamond inferred anonymous class. Latter case is to
2021 // be treated "as if as they were annotated" with @Override.
2022 boolean mustOverride = explicitOverride ||
2023 (env.info.isAnonymousDiamond && !m.isConstructor() && !m.isPrivate());
2024 if (mustOverride && !isOverrider(m)) {
2025 DiagnosticPosition pos = tree.pos();
2026 for (JCAnnotation a : tree.getModifiers().annotations) {
2027 if (a.annotationType.type.tsym == syms.overrideType.tsym) {
2028 pos = a.pos();
2029 break;
2030 }
2031 }
2032 log.error(pos,
2033 explicitOverride ? Errors.MethodDoesNotOverrideSuperclass :
2034 Errors.AnonymousDiamondMethodDoesNotOverrideSuperclass(Fragments.DiamondAnonymousMethodsImplicitlyOverride));
2035 }
2036 }
2037
2038 void checkOverride(JCTree tree, Type site, ClassSymbol origin, MethodSymbol m) {
2039 TypeSymbol c = site.tsym;
2040 for (Symbol sym : c.members().getSymbolsByName(m.name)) {
2041 if (m.overrides(sym, origin, types, false)) {
2042 if ((sym.flags() & ABSTRACT) == 0) {
2043 checkOverride(tree, m, (MethodSymbol)sym, origin);
2044 }
2045 }
2046 }
2047 }
2048
2049 private Filter<Symbol> equalsHasCodeFilter = new Filter<Symbol>() {
2050 public boolean accepts(Symbol s) {
2051 return MethodSymbol.implementation_filter.accepts(s) &&
2052 (s.flags() & BAD_OVERRIDE) == 0;
2053
2054 }
2055 };
2056
2057 public void checkClassOverrideEqualsAndHashIfNeeded(DiagnosticPosition pos,
2058 ClassSymbol someClass) {
2059 /* At present, annotations cannot possibly have a method that is override
2060 * equivalent with Object.equals(Object) but in any case the condition is
2061 * fine for completeness.
2062 */
2063 if (someClass == (ClassSymbol)syms.objectType.tsym ||
2064 someClass.isInterface() || someClass.isEnum() ||
2065 (someClass.flags() & ANNOTATION) != 0 ||
2066 (someClass.flags() & ABSTRACT) != 0) return;
2067 //anonymous inner classes implementing interfaces need especial treatment
2068 if (someClass.isAnonymous()) {
2069 List<Type> interfaces = types.interfaces(someClass.type);
2070 if (interfaces != null && !interfaces.isEmpty() &&
2071 interfaces.head.tsym == syms.comparatorType.tsym) return;
2072 }
2073 checkClassOverrideEqualsAndHash(pos, someClass);
2074 }
2075
2076 private void checkClassOverrideEqualsAndHash(DiagnosticPosition pos,
2077 ClassSymbol someClass) {
2078 if (lint.isEnabled(LintCategory.OVERRIDES)) {
2079 MethodSymbol equalsAtObject = (MethodSymbol)syms.objectType
2080 .tsym.members().findFirst(names.equals);
2081 MethodSymbol hashCodeAtObject = (MethodSymbol)syms.objectType
2082 .tsym.members().findFirst(names.hashCode);
2083 boolean overridesEquals = types.implementation(equalsAtObject,
2084 someClass, false, equalsHasCodeFilter).owner == someClass;
2085 boolean overridesHashCode = types.implementation(hashCodeAtObject,
2086 someClass, false, equalsHasCodeFilter) != hashCodeAtObject;
2087
2088 if (overridesEquals && !overridesHashCode) {
2089 log.warning(LintCategory.OVERRIDES, pos,
2090 "override.equals.but.not.hashcode", someClass);
2091 }
2092 }
2093 }
2094
2095 private boolean checkNameClash(ClassSymbol origin, Symbol s1, Symbol s2) {
2096 ClashFilter cf = new ClashFilter(origin.type);
2097 return (cf.accepts(s1) &&
2098 cf.accepts(s2) &&
2099 types.hasSameArgs(s1.erasure(types), s2.erasure(types)));
2100 }
2101
2102
2103 /** Check that all abstract members of given class have definitions.
2104 * @param pos Position to be used for error reporting.
2105 * @param c The class.
2106 */
2107 void checkAllDefined(DiagnosticPosition pos, ClassSymbol c) {
2108 MethodSymbol undef = types.firstUnimplementedAbstract(c);
2109 if (undef != null) {
2110 MethodSymbol undef1 =
2111 new MethodSymbol(undef.flags(), undef.name,
2112 types.memberType(c.type, undef), undef.owner);
2113 log.error(pos, "does.not.override.abstract",
2114 c, undef1, undef1.location());
2115 }
2116 }
2117
2118 void checkNonCyclicDecl(JCClassDecl tree) {
2119 CycleChecker cc = new CycleChecker();
2120 cc.scan(tree);
2121 if (!cc.errorFound && !cc.partialCheck) {
2122 tree.sym.flags_field |= ACYCLIC;
2123 }
2124 }
2125
2126 class CycleChecker extends TreeScanner {
2127
2128 List<Symbol> seenClasses = List.nil();
2129 boolean errorFound = false;
2130 boolean partialCheck = false;
2131
2132 private void checkSymbol(DiagnosticPosition pos, Symbol sym) {
2133 if (sym != null && sym.kind == TYP) {
2134 Env<AttrContext> classEnv = enter.getEnv((TypeSymbol)sym);
2135 if (classEnv != null) {
2136 DiagnosticSource prevSource = log.currentSource();
2137 try {
2138 log.useSource(classEnv.toplevel.sourcefile);
2139 scan(classEnv.tree);
2140 }
2141 finally {
2142 log.useSource(prevSource.getFile());
2143 }
2144 } else if (sym.kind == TYP) {
2145 checkClass(pos, sym, List.<JCTree>nil());
2146 }
2147 } else {
2148 //not completed yet
2149 partialCheck = true;
2150 }
2151 }
2152
2153 @Override
2154 public void visitSelect(JCFieldAccess tree) {
2155 super.visitSelect(tree);
2156 checkSymbol(tree.pos(), tree.sym);
2157 }
2158
2159 @Override
2160 public void visitIdent(JCIdent tree) {
2161 checkSymbol(tree.pos(), tree.sym);
2162 }
2163
2164 @Override
2165 public void visitTypeApply(JCTypeApply tree) {
2166 scan(tree.clazz);
2167 }
2168
2169 @Override
2170 public void visitTypeArray(JCArrayTypeTree tree) {
2171 scan(tree.elemtype);
2172 }
2173
2174 @Override
2175 public void visitClassDef(JCClassDecl tree) {
2176 List<JCTree> supertypes = List.nil();
2177 if (tree.getExtendsClause() != null) {
2178 supertypes = supertypes.prepend(tree.getExtendsClause());
2179 }
2180 if (tree.getImplementsClause() != null) {
2181 for (JCTree intf : tree.getImplementsClause()) {
2182 supertypes = supertypes.prepend(intf);
2183 }
2184 }
2185 checkClass(tree.pos(), tree.sym, supertypes);
2186 }
2187
2188 void checkClass(DiagnosticPosition pos, Symbol c, List<JCTree> supertypes) {
2189 if ((c.flags_field & ACYCLIC) != 0)
2190 return;
2191 if (seenClasses.contains(c)) {
2192 errorFound = true;
2193 noteCyclic(pos, (ClassSymbol)c);
2194 } else if (!c.type.isErroneous()) {
2195 try {
2196 seenClasses = seenClasses.prepend(c);
2197 if (c.type.hasTag(CLASS)) {
2198 if (supertypes.nonEmpty()) {
2199 scan(supertypes);
2200 }
2201 else {
2202 ClassType ct = (ClassType)c.type;
2203 if (ct.supertype_field == null ||
2204 ct.interfaces_field == null) {
2205 //not completed yet
2206 partialCheck = true;
2207 return;
2208 }
2209 checkSymbol(pos, ct.supertype_field.tsym);
2210 for (Type intf : ct.interfaces_field) {
2211 checkSymbol(pos, intf.tsym);
2212 }
2213 }
2214 if (c.owner.kind == TYP) {
2215 checkSymbol(pos, c.owner);
2216 }
2217 }
2218 } finally {
2219 seenClasses = seenClasses.tail;
2220 }
2221 }
2222 }
2223 }
2224
2225 /** Check for cyclic references. Issue an error if the
2226 * symbol of the type referred to has a LOCKED flag set.
2227 *
2228 * @param pos Position to be used for error reporting.
2229 * @param t The type referred to.
2230 */
2231 void checkNonCyclic(DiagnosticPosition pos, Type t) {
2232 checkNonCyclicInternal(pos, t);
2233 }
2234
2235
2236 void checkNonCyclic(DiagnosticPosition pos, TypeVar t) {
2237 checkNonCyclic1(pos, t, List.<TypeVar>nil());
2238 }
2239
2240 private void checkNonCyclic1(DiagnosticPosition pos, Type t, List<TypeVar> seen) {
2241 final TypeVar tv;
2242 if (t.hasTag(TYPEVAR) && (t.tsym.flags() & UNATTRIBUTED) != 0)
2243 return;
2244 if (seen.contains(t)) {
2245 tv = (TypeVar)t;
2246 tv.bound = types.createErrorType(t);
2247 log.error(pos, "cyclic.inheritance", t);
2248 } else if (t.hasTag(TYPEVAR)) {
2249 tv = (TypeVar)t;
2250 seen = seen.prepend(tv);
2251 for (Type b : types.getBounds(tv))
2252 checkNonCyclic1(pos, b, seen);
2253 }
2254 }
2255
2256 /** Check for cyclic references. Issue an error if the
2257 * symbol of the type referred to has a LOCKED flag set.
2258 *
2259 * @param pos Position to be used for error reporting.
2260 * @param t The type referred to.
2261 * @returns True if the check completed on all attributed classes
2262 */
2263 private boolean checkNonCyclicInternal(DiagnosticPosition pos, Type t) {
2264 boolean complete = true; // was the check complete?
2265 //- System.err.println("checkNonCyclicInternal("+t+");");//DEBUG
2266 Symbol c = t.tsym;
2267 if ((c.flags_field & ACYCLIC) != 0) return true;
2268
2269 if ((c.flags_field & LOCKED) != 0) {
2270 noteCyclic(pos, (ClassSymbol)c);
2271 } else if (!c.type.isErroneous()) {
2272 try {
2273 c.flags_field |= LOCKED;
2274 if (c.type.hasTag(CLASS)) {
2275 ClassType clazz = (ClassType)c.type;
2276 if (clazz.interfaces_field != null)
2277 for (List<Type> l=clazz.interfaces_field; l.nonEmpty(); l=l.tail)
2278 complete &= checkNonCyclicInternal(pos, l.head);
2279 if (clazz.supertype_field != null) {
2280 Type st = clazz.supertype_field;
2281 if (st != null && st.hasTag(CLASS))
2282 complete &= checkNonCyclicInternal(pos, st);
2283 }
2284 if (c.owner.kind == TYP)
2285 complete &= checkNonCyclicInternal(pos, c.owner.type);
2286 }
2287 } finally {
2288 c.flags_field &= ~LOCKED;
2289 }
2290 }
2291 if (complete)
2292 complete = ((c.flags_field & UNATTRIBUTED) == 0) && c.isCompleted();
2293 if (complete) c.flags_field |= ACYCLIC;
2294 return complete;
2295 }
2296
2297 /** Note that we found an inheritance cycle. */
2298 private void noteCyclic(DiagnosticPosition pos, ClassSymbol c) {
2299 log.error(pos, "cyclic.inheritance", c);
2300 for (List<Type> l=types.interfaces(c.type); l.nonEmpty(); l=l.tail)
2301 l.head = types.createErrorType((ClassSymbol)l.head.tsym, Type.noType);
2302 Type st = types.supertype(c.type);
2303 if (st.hasTag(CLASS))
2304 ((ClassType)c.type).supertype_field = types.createErrorType((ClassSymbol)st.tsym, Type.noType);
2305 c.type = types.createErrorType(c, c.type);
2306 c.flags_field |= ACYCLIC;
2307 }
2308
2309 /** Check that all methods which implement some
2310 * method conform to the method they implement.
2311 * @param tree The class definition whose members are checked.
2312 */
2313 void checkImplementations(JCClassDecl tree) {
2314 checkImplementations(tree, tree.sym, tree.sym);
2315 }
2316 //where
2317 /** Check that all methods which implement some
2318 * method in `ic' conform to the method they implement.
2319 */
2320 void checkImplementations(JCTree tree, ClassSymbol origin, ClassSymbol ic) {
2321 for (List<Type> l = types.closure(ic.type); l.nonEmpty(); l = l.tail) {
2322 ClassSymbol lc = (ClassSymbol)l.head.tsym;
2323 if ((lc.flags() & ABSTRACT) != 0) {
2324 for (Symbol sym : lc.members().getSymbols(NON_RECURSIVE)) {
2325 if (sym.kind == MTH &&
2326 (sym.flags() & (STATIC|ABSTRACT)) == ABSTRACT) {
2327 MethodSymbol absmeth = (MethodSymbol)sym;
2328 MethodSymbol implmeth = absmeth.implementation(origin, types, false);
2329 if (implmeth != null && implmeth != absmeth &&
2330 (implmeth.owner.flags() & INTERFACE) ==
2331 (origin.flags() & INTERFACE)) {
2332 // don't check if implmeth is in a class, yet
2333 // origin is an interface. This case arises only
2334 // if implmeth is declared in Object. The reason is
2335 // that interfaces really don't inherit from
2336 // Object it's just that the compiler represents
2337 // things that way.
2338 checkOverride(tree, implmeth, absmeth, origin);
2339 }
2340 }
2341 }
2342 }
2343 }
2344 }
2345
2346 /** Check that all abstract methods implemented by a class are
2347 * mutually compatible.
2348 * @param pos Position to be used for error reporting.
2349 * @param c The class whose interfaces are checked.
2350 */
2351 void checkCompatibleSupertypes(DiagnosticPosition pos, Type c) {
2352 List<Type> supertypes = types.interfaces(c);
2353 Type supertype = types.supertype(c);
2354 if (supertype.hasTag(CLASS) &&
2355 (supertype.tsym.flags() & ABSTRACT) != 0)
2356 supertypes = supertypes.prepend(supertype);
2357 for (List<Type> l = supertypes; l.nonEmpty(); l = l.tail) {
2358 if (!l.head.getTypeArguments().isEmpty() &&
2359 !checkCompatibleAbstracts(pos, l.head, l.head, c))
2360 return;
2361 for (List<Type> m = supertypes; m != l; m = m.tail)
2362 if (!checkCompatibleAbstracts(pos, l.head, m.head, c))
2363 return;
2364 }
2365 checkCompatibleConcretes(pos, c);
2366 }
2367
2368 void checkConflicts(DiagnosticPosition pos, Symbol sym, TypeSymbol c) {
2369 for (Type ct = c.type; ct != Type.noType ; ct = types.supertype(ct)) {
2370 for (Symbol sym2 : ct.tsym.members().getSymbolsByName(sym.name, NON_RECURSIVE)) {
2371 // VM allows methods and variables with differing types
2372 if (sym.kind == sym2.kind &&
2373 types.isSameType(types.erasure(sym.type), types.erasure(sym2.type)) &&
2374 sym != sym2 &&
2375 (sym.flags() & Flags.SYNTHETIC) != (sym2.flags() & Flags.SYNTHETIC) &&
2376 (sym.flags() & BRIDGE) == 0 && (sym2.flags() & BRIDGE) == 0) {
2377 syntheticError(pos, (sym2.flags() & SYNTHETIC) == 0 ? sym2 : sym);
2378 return;
2379 }
2380 }
2381 }
2382 }
2383
2384 /** Check that all non-override equivalent methods accessible from 'site'
2385 * are mutually compatible (JLS 8.4.8/9.4.1).
2386 *
2387 * @param pos Position to be used for error reporting.
2388 * @param site The class whose methods are checked.
2389 * @param sym The method symbol to be checked.
2390 */
2391 void checkOverrideClashes(DiagnosticPosition pos, Type site, MethodSymbol sym) {
2392 ClashFilter cf = new ClashFilter(site);
2393 //for each method m1 that is overridden (directly or indirectly)
2394 //by method 'sym' in 'site'...
2395
2396 List<MethodSymbol> potentiallyAmbiguousList = List.nil();
2397 boolean overridesAny = false;
2398 for (Symbol m1 : types.membersClosure(site, false).getSymbolsByName(sym.name, cf)) {
2399 if (!sym.overrides(m1, site.tsym, types, false)) {
2400 if (m1 == sym) {
2401 continue;
2402 }
2403
2404 if (!overridesAny) {
2405 potentiallyAmbiguousList = potentiallyAmbiguousList.prepend((MethodSymbol)m1);
2406 }
2407 continue;
2408 }
2409
2410 if (m1 != sym) {
2411 overridesAny = true;
2412 potentiallyAmbiguousList = List.nil();
2413 }
2414
2415 //...check each method m2 that is a member of 'site'
2416 for (Symbol m2 : types.membersClosure(site, false).getSymbolsByName(sym.name, cf)) {
2417 if (m2 == m1) continue;
2418 //if (i) the signature of 'sym' is not a subsignature of m1 (seen as
2419 //a member of 'site') and (ii) m1 has the same erasure as m2, issue an error
2420 if (!types.isSubSignature(sym.type, types.memberType(site, m2), allowStrictMethodClashCheck) &&
2421 types.hasSameArgs(m2.erasure(types), m1.erasure(types))) {
2422 sym.flags_field |= CLASH;
2423 String key = m1 == sym ?
2424 "name.clash.same.erasure.no.override" :
2425 "name.clash.same.erasure.no.override.1";
2426 log.error(pos,
2427 key,
2428 sym, sym.location(),
2429 m2, m2.location(),
2430 m1, m1.location());
2431 return;
2432 }
2433 }
2434 }
2435
2436 if (!overridesAny) {
2437 for (MethodSymbol m: potentiallyAmbiguousList) {
2438 checkPotentiallyAmbiguousOverloads(pos, site, sym, m);
2439 }
2440 }
2441 }
2442
2443 /** Check that all static methods accessible from 'site' are
2444 * mutually compatible (JLS 8.4.8).
2445 *
2446 * @param pos Position to be used for error reporting.
2447 * @param site The class whose methods are checked.
2448 * @param sym The method symbol to be checked.
2449 */
2450 void checkHideClashes(DiagnosticPosition pos, Type site, MethodSymbol sym) {
2451 ClashFilter cf = new ClashFilter(site);
2452 //for each method m1 that is a member of 'site'...
2453 for (Symbol s : types.membersClosure(site, true).getSymbolsByName(sym.name, cf)) {
2454 //if (i) the signature of 'sym' is not a subsignature of m1 (seen as
2455 //a member of 'site') and (ii) 'sym' has the same erasure as m1, issue an error
2456 if (!types.isSubSignature(sym.type, types.memberType(site, s), allowStrictMethodClashCheck)) {
2457 if (types.hasSameArgs(s.erasure(types), sym.erasure(types))) {
2458 log.error(pos,
2459 "name.clash.same.erasure.no.hide",
2460 sym, sym.location(),
2461 s, s.location());
2462 return;
2463 } else {
2464 checkPotentiallyAmbiguousOverloads(pos, site, sym, (MethodSymbol)s);
2465 }
2466 }
2467 }
2468 }
2469
2470 //where
2471 private class ClashFilter implements Filter<Symbol> {
2472
2473 Type site;
2474
2475 ClashFilter(Type site) {
2476 this.site = site;
2477 }
2478
2479 boolean shouldSkip(Symbol s) {
2480 return (s.flags() & CLASH) != 0 &&
2481 s.owner == site.tsym;
2482 }
2483
2484 public boolean accepts(Symbol s) {
2485 return s.kind == MTH &&
2486 (s.flags() & SYNTHETIC) == 0 &&
2487 !shouldSkip(s) &&
2488 s.isInheritedIn(site.tsym, types) &&
2489 !s.isConstructor();
2490 }
2491 }
2492
2493 void checkDefaultMethodClashes(DiagnosticPosition pos, Type site) {
2494 DefaultMethodClashFilter dcf = new DefaultMethodClashFilter(site);
2495 for (Symbol m : types.membersClosure(site, false).getSymbols(dcf)) {
2496 Assert.check(m.kind == MTH);
2497 List<MethodSymbol> prov = types.interfaceCandidates(site, (MethodSymbol)m);
2498 if (prov.size() > 1) {
2499 ListBuffer<Symbol> abstracts = new ListBuffer<>();
2500 ListBuffer<Symbol> defaults = new ListBuffer<>();
2501 for (MethodSymbol provSym : prov) {
2502 if ((provSym.flags() & DEFAULT) != 0) {
2503 defaults = defaults.append(provSym);
2504 } else if ((provSym.flags() & ABSTRACT) != 0) {
2505 abstracts = abstracts.append(provSym);
2506 }
2507 if (defaults.nonEmpty() && defaults.size() + abstracts.size() >= 2) {
2508 //strong semantics - issue an error if two sibling interfaces
2509 //have two override-equivalent defaults - or if one is abstract
2510 //and the other is default
2511 String errKey;
2512 Symbol s1 = defaults.first();
2513 Symbol s2;
2514 if (defaults.size() > 1) {
2515 errKey = "types.incompatible.unrelated.defaults";
2516 s2 = defaults.toList().tail.head;
2517 } else {
2518 errKey = "types.incompatible.abstract.default";
2519 s2 = abstracts.first();
2520 }
2521 log.error(pos, errKey,
2522 Kinds.kindName(site.tsym), site,
2523 m.name, types.memberType(site, m).getParameterTypes(),
2524 s1.location(), s2.location());
2525 break;
2526 }
2527 }
2528 }
2529 }
2530 }
2531
2532 //where
2533 private class DefaultMethodClashFilter implements Filter<Symbol> {
2534
2535 Type site;
2536
2537 DefaultMethodClashFilter(Type site) {
2538 this.site = site;
2539 }
2540
2541 public boolean accepts(Symbol s) {
2542 return s.kind == MTH &&
2543 (s.flags() & DEFAULT) != 0 &&
2544 s.isInheritedIn(site.tsym, types) &&
2545 !s.isConstructor();
2546 }
2547 }
2548
2549 /**
2550 * Report warnings for potentially ambiguous method declarations. Two declarations
2551 * are potentially ambiguous if they feature two unrelated functional interface
2552 * in same argument position (in which case, a call site passing an implicit
2553 * lambda would be ambiguous).
2554 */
2555 void checkPotentiallyAmbiguousOverloads(DiagnosticPosition pos, Type site,
2556 MethodSymbol msym1, MethodSymbol msym2) {
2557 if (msym1 != msym2 &&
2558 allowDefaultMethods &&
2559 lint.isEnabled(LintCategory.OVERLOADS) &&
2560 (msym1.flags() & POTENTIALLY_AMBIGUOUS) == 0 &&
2561 (msym2.flags() & POTENTIALLY_AMBIGUOUS) == 0) {
2562 Type mt1 = types.memberType(site, msym1);
2563 Type mt2 = types.memberType(site, msym2);
2564 //if both generic methods, adjust type variables
2565 if (mt1.hasTag(FORALL) && mt2.hasTag(FORALL) &&
2566 types.hasSameBounds((ForAll)mt1, (ForAll)mt2)) {
2567 mt2 = types.subst(mt2, ((ForAll)mt2).tvars, ((ForAll)mt1).tvars);
2568 }
2569 //expand varargs methods if needed
2570 int maxLength = Math.max(mt1.getParameterTypes().length(), mt2.getParameterTypes().length());
2571 List<Type> args1 = rs.adjustArgs(mt1.getParameterTypes(), msym1, maxLength, true);
2572 List<Type> args2 = rs.adjustArgs(mt2.getParameterTypes(), msym2, maxLength, true);
2573 //if arities don't match, exit
2574 if (args1.length() != args2.length()) return;
2575 boolean potentiallyAmbiguous = false;
2576 while (args1.nonEmpty() && args2.nonEmpty()) {
2577 Type s = args1.head;
2578 Type t = args2.head;
2579 if (!types.isSubtype(t, s) && !types.isSubtype(s, t)) {
2580 if (types.isFunctionalInterface(s) && types.isFunctionalInterface(t) &&
2581 types.findDescriptorType(s).getParameterTypes().length() > 0 &&
2582 types.findDescriptorType(s).getParameterTypes().length() ==
2583 types.findDescriptorType(t).getParameterTypes().length()) {
2584 potentiallyAmbiguous = true;
2585 } else {
2586 break;
2587 }
2588 }
2589 args1 = args1.tail;
2590 args2 = args2.tail;
2591 }
2592 if (potentiallyAmbiguous) {
2593 //we found two incompatible functional interfaces with same arity
2594 //this means a call site passing an implicit lambda would be ambigiuous
2595 msym1.flags_field |= POTENTIALLY_AMBIGUOUS;
2596 msym2.flags_field |= POTENTIALLY_AMBIGUOUS;
2597 log.warning(LintCategory.OVERLOADS, pos, "potentially.ambiguous.overload",
2598 msym1, msym1.location(),
2599 msym2, msym2.location());
2600 return;
2601 }
2602 }
2603 }
2604
2605 void checkElemAccessFromSerializableLambda(final JCTree tree) {
2606 if (warnOnAccessToSensitiveMembers) {
2607 Symbol sym = TreeInfo.symbol(tree);
2608 if (!sym.kind.matches(KindSelector.VAL_MTH)) {
2609 return;
2610 }
2611
2612 if (sym.kind == VAR) {
2613 if ((sym.flags() & PARAMETER) != 0 ||
2614 sym.isLocal() ||
2615 sym.name == names._this ||
2616 sym.name == names._super) {
2617 return;
2618 }
2619 }
2620
2621 if (!types.isSubtype(sym.owner.type, syms.serializableType) &&
2622 isEffectivelyNonPublic(sym)) {
2623 log.warning(tree.pos(),
2624 "access.to.sensitive.member.from.serializable.element", sym);
2625 }
2626 }
2627 }
2628
2629 private boolean isEffectivelyNonPublic(Symbol sym) {
2630 if (sym.packge() == syms.rootPackage) {
2631 return false;
2632 }
2633
2634 while (sym.kind != PCK) {
2635 if ((sym.flags() & PUBLIC) == 0) {
2636 return true;
2637 }
2638 sym = sym.owner;
2639 }
2640 return false;
2641 }
2642
2643 /** Report a conflict between a user symbol and a synthetic symbol.
2644 */
2645 private void syntheticError(DiagnosticPosition pos, Symbol sym) {
2646 if (!sym.type.isErroneous()) {
2647 log.error(pos, "synthetic.name.conflict", sym, sym.location());
2648 }
2649 }
2650
2651 /** Check that class c does not implement directly or indirectly
2652 * the same parameterized interface with two different argument lists.
2653 * @param pos Position to be used for error reporting.
2654 * @param type The type whose interfaces are checked.
2655 */
2656 void checkClassBounds(DiagnosticPosition pos, Type type) {
2657 checkClassBounds(pos, new HashMap<TypeSymbol,Type>(), type);
2658 }
2659 //where
2660 /** Enter all interfaces of type `type' into the hash table `seensofar'
2661 * with their class symbol as key and their type as value. Make
2662 * sure no class is entered with two different types.
2663 */
2664 void checkClassBounds(DiagnosticPosition pos,
2665 Map<TypeSymbol,Type> seensofar,
2666 Type type) {
2667 if (type.isErroneous()) return;
2668 for (List<Type> l = types.interfaces(type); l.nonEmpty(); l = l.tail) {
2669 Type it = l.head;
2670 Type oldit = seensofar.put(it.tsym, it);
2671 if (oldit != null) {
2672 List<Type> oldparams = oldit.allparams();
2673 List<Type> newparams = it.allparams();
2674 if (!types.containsTypeEquivalent(oldparams, newparams))
2675 log.error(pos, "cant.inherit.diff.arg",
2676 it.tsym, Type.toString(oldparams),
2677 Type.toString(newparams));
2678 }
2679 checkClassBounds(pos, seensofar, it);
2680 }
2681 Type st = types.supertype(type);
2682 if (st != Type.noType) checkClassBounds(pos, seensofar, st);
2683 }
2684
2685 /** Enter interface into into set.
2686 * If it existed already, issue a "repeated interface" error.
2687 */
2688 void checkNotRepeated(DiagnosticPosition pos, Type it, Set<Type> its) {
2689 if (its.contains(it))
2690 log.error(pos, "repeated.interface");
2691 else {
2692 its.add(it);
2693 }
2694 }
2695
2696 /* *************************************************************************
2697 * Check annotations
2698 **************************************************************************/
2699
2700 /**
2701 * Recursively validate annotations values
2702 */
2703 void validateAnnotationTree(JCTree tree) {
2704 class AnnotationValidator extends TreeScanner {
2705 @Override
2706 public void visitAnnotation(JCAnnotation tree) {
2707 if (!tree.type.isErroneous()) {
2708 super.visitAnnotation(tree);
2709 validateAnnotation(tree);
2710 }
2711 }
2712 }
2713 tree.accept(new AnnotationValidator());
2714 }
2715
2716 /**
2717 * {@literal
2718 * Annotation types are restricted to primitives, String, an
2719 * enum, an annotation, Class, Class<?>, Class<? extends
2720 * Anything>, arrays of the preceding.
2721 * }
2722 */
2723 void validateAnnotationType(JCTree restype) {
2724 // restype may be null if an error occurred, so don't bother validating it
2725 if (restype != null) {
2726 validateAnnotationType(restype.pos(), restype.type);
2727 }
2728 }
2729
2730 void validateAnnotationType(DiagnosticPosition pos, Type type) {
2731 if (type.isPrimitive()) return;
2732 if (types.isSameType(type, syms.stringType)) return;
2733 if ((type.tsym.flags() & Flags.ENUM) != 0) return;
2734 if ((type.tsym.flags() & Flags.ANNOTATION) != 0) return;
2735 if (types.cvarLowerBound(type).tsym == syms.classType.tsym) return;
2736 if (types.isArray(type) && !types.isArray(types.elemtype(type))) {
2737 validateAnnotationType(pos, types.elemtype(type));
2738 return;
2739 }
2740 log.error(pos, "invalid.annotation.member.type");
2741 }
2742
2743 /**
2744 * "It is also a compile-time error if any method declared in an
2745 * annotation type has a signature that is override-equivalent to
2746 * that of any public or protected method declared in class Object
2747 * or in the interface annotation.Annotation."
2748 *
2749 * @jls 9.6 Annotation Types
2750 */
2751 void validateAnnotationMethod(DiagnosticPosition pos, MethodSymbol m) {
2752 for (Type sup = syms.annotationType; sup.hasTag(CLASS); sup = types.supertype(sup)) {
2753 Scope s = sup.tsym.members();
2754 for (Symbol sym : s.getSymbolsByName(m.name)) {
2755 if (sym.kind == MTH &&
2756 (sym.flags() & (PUBLIC | PROTECTED)) != 0 &&
2757 types.overrideEquivalent(m.type, sym.type))
2758 log.error(pos, "intf.annotation.member.clash", sym, sup);
2759 }
2760 }
2761 }
2762
2763 /** Check the annotations of a symbol.
2764 */
2765 public void validateAnnotations(List<JCAnnotation> annotations, Symbol s) {
2766 for (JCAnnotation a : annotations)
2767 validateAnnotation(a, s);
2768 }
2769
2770 /** Check the type annotations.
2771 */
2772 public void validateTypeAnnotations(List<JCAnnotation> annotations, boolean isTypeParameter) {
2773 for (JCAnnotation a : annotations)
2774 validateTypeAnnotation(a, isTypeParameter);
2775 }
2776
2777 /** Check an annotation of a symbol.
2778 */
2779 private void validateAnnotation(JCAnnotation a, Symbol s) {
2780 validateAnnotationTree(a);
2781
2782 if (!annotationApplicable(a, s))
2783 log.error(a.pos(), "annotation.type.not.applicable");
2784
2785 if (a.annotationType.type.tsym == syms.functionalInterfaceType.tsym) {
2786 if (s.kind != TYP) {
2787 log.error(a.pos(), "bad.functional.intf.anno");
2788 } else if (!s.isInterface() || (s.flags() & ANNOTATION) != 0) {
2789 log.error(a.pos(), "bad.functional.intf.anno.1", diags.fragment("not.a.functional.intf", s));
2790 }
2791 }
2792 }
2793
2794 public void validateTypeAnnotation(JCAnnotation a, boolean isTypeParameter) {
2795 Assert.checkNonNull(a.type);
2796 validateAnnotationTree(a);
2797
2798 if (a.hasTag(TYPE_ANNOTATION) &&
2799 !a.annotationType.type.isErroneous() &&
2800 !isTypeAnnotation(a, isTypeParameter)) {
2801 log.error(a.pos(), Errors.AnnotationTypeNotApplicableToType(a.type));
2802 }
2803 }
2804
2805 /**
2806 * Validate the proposed container 'repeatable' on the
2807 * annotation type symbol 's'. Report errors at position
2808 * 'pos'.
2809 *
2810 * @param s The (annotation)type declaration annotated with a @Repeatable
2811 * @param repeatable the @Repeatable on 's'
2812 * @param pos where to report errors
2813 */
2814 public void validateRepeatable(TypeSymbol s, Attribute.Compound repeatable, DiagnosticPosition pos) {
2815 Assert.check(types.isSameType(repeatable.type, syms.repeatableType));
2816
2817 Type t = null;
2818 List<Pair<MethodSymbol,Attribute>> l = repeatable.values;
2819 if (!l.isEmpty()) {
2820 Assert.check(l.head.fst.name == names.value);
2821 t = ((Attribute.Class)l.head.snd).getValue();
2822 }
2823
2824 if (t == null) {
2825 // errors should already have been reported during Annotate
2826 return;
2827 }
2828
2829 validateValue(t.tsym, s, pos);
2830 validateRetention(t.tsym, s, pos);
2831 validateDocumented(t.tsym, s, pos);
2832 validateInherited(t.tsym, s, pos);
2833 validateTarget(t.tsym, s, pos);
2834 validateDefault(t.tsym, pos);
2835 }
2836
2837 private void validateValue(TypeSymbol container, TypeSymbol contained, DiagnosticPosition pos) {
2838 Symbol sym = container.members().findFirst(names.value);
2839 if (sym != null && sym.kind == MTH) {
2840 MethodSymbol m = (MethodSymbol) sym;
2841 Type ret = m.getReturnType();
2842 if (!(ret.hasTag(ARRAY) && types.isSameType(((ArrayType)ret).elemtype, contained.type))) {
2843 log.error(pos, "invalid.repeatable.annotation.value.return",
2844 container, ret, types.makeArrayType(contained.type));
2845 }
2846 } else {
2847 log.error(pos, "invalid.repeatable.annotation.no.value", container);
2848 }
2849 }
2850
2851 private void validateRetention(TypeSymbol container, TypeSymbol contained, DiagnosticPosition pos) {
2852 Attribute.RetentionPolicy containerRetention = types.getRetention(container);
2853 Attribute.RetentionPolicy containedRetention = types.getRetention(contained);
2854
2855 boolean error = false;
2856 switch (containedRetention) {
2857 case RUNTIME:
2858 if (containerRetention != Attribute.RetentionPolicy.RUNTIME) {
2859 error = true;
2860 }
2861 break;
2862 case CLASS:
2863 if (containerRetention == Attribute.RetentionPolicy.SOURCE) {
2864 error = true;
2865 }
2866 }
2867 if (error ) {
2868 log.error(pos, "invalid.repeatable.annotation.retention",
2869 container, containerRetention,
2870 contained, containedRetention);
2871 }
2872 }
2873
2874 private void validateDocumented(Symbol container, Symbol contained, DiagnosticPosition pos) {
2875 if (contained.attribute(syms.documentedType.tsym) != null) {
2876 if (container.attribute(syms.documentedType.tsym) == null) {
2877 log.error(pos, "invalid.repeatable.annotation.not.documented", container, contained);
2878 }
2879 }
2880 }
2881
2882 private void validateInherited(Symbol container, Symbol contained, DiagnosticPosition pos) {
2883 if (contained.attribute(syms.inheritedType.tsym) != null) {
2884 if (container.attribute(syms.inheritedType.tsym) == null) {
2885 log.error(pos, "invalid.repeatable.annotation.not.inherited", container, contained);
2886 }
2887 }
2888 }
2889
2890 private void validateTarget(TypeSymbol container, TypeSymbol contained, DiagnosticPosition pos) {
2891 // The set of targets the container is applicable to must be a subset
2892 // (with respect to annotation target semantics) of the set of targets
2893 // the contained is applicable to. The target sets may be implicit or
2894 // explicit.
2895
2896 Set<Name> containerTargets;
2897 Attribute.Array containerTarget = getAttributeTargetAttribute(container);
2898 if (containerTarget == null) {
2899 containerTargets = getDefaultTargetSet();
2900 } else {
2901 containerTargets = new HashSet<>();
2902 for (Attribute app : containerTarget.values) {
2903 if (!(app instanceof Attribute.Enum)) {
2904 continue; // recovery
2905 }
2906 Attribute.Enum e = (Attribute.Enum)app;
2907 containerTargets.add(e.value.name);
2908 }
2909 }
2910
2911 Set<Name> containedTargets;
2912 Attribute.Array containedTarget = getAttributeTargetAttribute(contained);
2913 if (containedTarget == null) {
2914 containedTargets = getDefaultTargetSet();
2915 } else {
2916 containedTargets = new HashSet<>();
2917 for (Attribute app : containedTarget.values) {
2918 if (!(app instanceof Attribute.Enum)) {
2919 continue; // recovery
2920 }
2921 Attribute.Enum e = (Attribute.Enum)app;
2922 containedTargets.add(e.value.name);
2923 }
2924 }
2925
2926 if (!isTargetSubsetOf(containerTargets, containedTargets)) {
2927 log.error(pos, "invalid.repeatable.annotation.incompatible.target", container, contained);
2928 }
2929 }
2930
2931 /* get a set of names for the default target */
2932 private Set<Name> getDefaultTargetSet() {
2933 if (defaultTargets == null) {
2934 Set<Name> targets = new HashSet<>();
2935 targets.add(names.ANNOTATION_TYPE);
2936 targets.add(names.CONSTRUCTOR);
2937 targets.add(names.FIELD);
2938 targets.add(names.LOCAL_VARIABLE);
2939 targets.add(names.METHOD);
2940 targets.add(names.PACKAGE);
2941 targets.add(names.PARAMETER);
2942 targets.add(names.TYPE);
2943
2944 defaultTargets = java.util.Collections.unmodifiableSet(targets);
2945 }
2946
2947 return defaultTargets;
2948 }
2949 private Set<Name> defaultTargets;
2950
2951
2952 /** Checks that s is a subset of t, with respect to ElementType
2953 * semantics, specifically {ANNOTATION_TYPE} is a subset of {TYPE},
2954 * and {TYPE_USE} covers the set {ANNOTATION_TYPE, TYPE, TYPE_USE,
2955 * TYPE_PARAMETER}.
2956 */
2957 private boolean isTargetSubsetOf(Set<Name> s, Set<Name> t) {
2958 // Check that all elements in s are present in t
2959 for (Name n2 : s) {
2960 boolean currentElementOk = false;
2961 for (Name n1 : t) {
2962 if (n1 == n2) {
2963 currentElementOk = true;
2964 break;
2965 } else if (n1 == names.TYPE && n2 == names.ANNOTATION_TYPE) {
2966 currentElementOk = true;
2967 break;
2968 } else if (n1 == names.TYPE_USE &&
2969 (n2 == names.TYPE ||
2970 n2 == names.ANNOTATION_TYPE ||
2971 n2 == names.TYPE_PARAMETER)) {
2972 currentElementOk = true;
2973 break;
2974 }
2975 }
2976 if (!currentElementOk)
2977 return false;
2978 }
2979 return true;
2980 }
2981
2982 private void validateDefault(Symbol container, DiagnosticPosition pos) {
2983 // validate that all other elements of containing type has defaults
2984 Scope scope = container.members();
2985 for(Symbol elm : scope.getSymbols()) {
2986 if (elm.name != names.value &&
2987 elm.kind == MTH &&
2988 ((MethodSymbol)elm).defaultValue == null) {
2989 log.error(pos,
2990 "invalid.repeatable.annotation.elem.nondefault",
2991 container,
2992 elm);
2993 }
2994 }
2995 }
2996
2997 /** Is s a method symbol that overrides a method in a superclass? */
2998 boolean isOverrider(Symbol s) {
2999 if (s.kind != MTH || s.isStatic())
3000 return false;
3001 MethodSymbol m = (MethodSymbol)s;
3002 TypeSymbol owner = (TypeSymbol)m.owner;
3003 for (Type sup : types.closure(owner.type)) {
3004 if (sup == owner.type)
3005 continue; // skip "this"
3006 Scope scope = sup.tsym.members();
3007 for (Symbol sym : scope.getSymbolsByName(m.name)) {
3008 if (!sym.isStatic() && m.overrides(sym, owner, types, true))
3009 return true;
3010 }
3011 }
3012 return false;
3013 }
3014
3015 /** Is the annotation applicable to types? */
3016 protected boolean isTypeAnnotation(JCAnnotation a, boolean isTypeParameter) {
3017 List<Attribute> targets = typeAnnotations.annotationTargets(a.annotationType.type.tsym);
3018 return (targets == null) ?
3019 false :
3020 targets.stream()
3021 .anyMatch(attr -> isTypeAnnotation(attr, isTypeParameter));
3022 }
3023 //where
3024 boolean isTypeAnnotation(Attribute a, boolean isTypeParameter) {
3025 Attribute.Enum e = (Attribute.Enum)a;
3026 return (e.value.name == names.TYPE_USE ||
3027 (isTypeParameter && e.value.name == names.TYPE_PARAMETER));
3028 }
3029
3030 /** Is the annotation applicable to the symbol? */
3031 boolean annotationApplicable(JCAnnotation a, Symbol s) {
3032 Attribute.Array arr = getAttributeTargetAttribute(a.annotationType.type.tsym);
3033 Name[] targets;
3034
3035 if (arr == null) {
3036 targets = defaultTargetMetaInfo(a, s);
3037 } else {
3038 // TODO: can we optimize this?
3039 targets = new Name[arr.values.length];
3040 for (int i=0; i<arr.values.length; ++i) {
3041 Attribute app = arr.values[i];
3042 if (!(app instanceof Attribute.Enum)) {
3043 return true; // recovery
3044 }
3045 Attribute.Enum e = (Attribute.Enum) app;
3046 targets[i] = e.value.name;
3047 }
3048 }
3049 for (Name target : targets) {
3050 if (target == names.TYPE) {
3051 if (s.kind == TYP)
3052 return true;
3053 } else if (target == names.FIELD) {
3054 if (s.kind == VAR && s.owner.kind != MTH)
3055 return true;
3056 } else if (target == names.METHOD) {
3057 if (s.kind == MTH && !s.isConstructor())
3058 return true;
3059 } else if (target == names.PARAMETER) {
3060 if (s.kind == VAR && s.owner.kind == MTH &&
3061 (s.flags() & PARAMETER) != 0) {
3062 return true;
3063 }
3064 } else if (target == names.CONSTRUCTOR) {
3065 if (s.kind == MTH && s.isConstructor())
3066 return true;
3067 } else if (target == names.LOCAL_VARIABLE) {
3068 if (s.kind == VAR && s.owner.kind == MTH &&
3069 (s.flags() & PARAMETER) == 0) {
3070 return true;
3071 }
3072 } else if (target == names.ANNOTATION_TYPE) {
3073 if (s.kind == TYP && (s.flags() & ANNOTATION) != 0) {
3074 return true;
3075 }
3076 } else if (target == names.PACKAGE) {
3077 if (s.kind == PCK)
3078 return true;
3079 } else if (target == names.TYPE_USE) {
3080 if (s.kind == TYP || s.kind == VAR ||
3081 (s.kind == MTH && !s.isConstructor() &&
3082 !s.type.getReturnType().hasTag(VOID)) ||
3083 (s.kind == MTH && s.isConstructor())) {
3084 return true;
3085 }
3086 } else if (target == names.TYPE_PARAMETER) {
3087 if (s.kind == TYP && s.type.hasTag(TYPEVAR))
3088 return true;
3089 } else
3090 return true; // Unknown ElementType. This should be an error at declaration site,
3091 // assume applicable.
3092 }
3093 return false;
3094 }
3095
3096
3097 Attribute.Array getAttributeTargetAttribute(TypeSymbol s) {
3098 Attribute.Compound atTarget = s.getAnnotationTypeMetadata().getTarget();
3099 if (atTarget == null) return null; // ok, is applicable
3100 Attribute atValue = atTarget.member(names.value);
3101 if (!(atValue instanceof Attribute.Array)) return null; // error recovery
3102 return (Attribute.Array) atValue;
3103 }
3104
3105 private final Name[] dfltTargetMeta;
3106 private Name[] defaultTargetMetaInfo(JCAnnotation a, Symbol s) {
3107 return dfltTargetMeta;
3108 }
3109
3110 /** Check an annotation value.
3111 *
3112 * @param a The annotation tree to check
3113 * @return true if this annotation tree is valid, otherwise false
3114 */
3115 public boolean validateAnnotationDeferErrors(JCAnnotation a) {
3116 boolean res = false;
3117 final Log.DiagnosticHandler diagHandler = new Log.DiscardDiagnosticHandler(log);
3118 try {
3119 res = validateAnnotation(a);
3120 } finally {
3121 log.popDiagnosticHandler(diagHandler);
3122 }
3123 return res;
3124 }
3125
3126 private boolean validateAnnotation(JCAnnotation a) {
3127 boolean isValid = true;
3128 AnnotationTypeMetadata metadata = a.annotationType.type.tsym.getAnnotationTypeMetadata();
3129
3130 // collect an inventory of the annotation elements
3131 Set<MethodSymbol> elements = metadata.getAnnotationElements();
3132
3133 // remove the ones that are assigned values
3134 for (JCTree arg : a.args) {
3135 if (!arg.hasTag(ASSIGN)) continue; // recovery
3136 JCAssign assign = (JCAssign)arg;
3137 Symbol m = TreeInfo.symbol(assign.lhs);
3138 if (m == null || m.type.isErroneous()) continue;
3139 if (!elements.remove(m)) {
3140 isValid = false;
3141 log.error(assign.lhs.pos(), "duplicate.annotation.member.value",
3142 m.name, a.type);
3143 }
3144 }
3145
3146 // all the remaining ones better have default values
3147 List<Name> missingDefaults = List.nil();
3148 Set<MethodSymbol> membersWithDefault = metadata.getAnnotationElementsWithDefault();
3149 for (MethodSymbol m : elements) {
3150 if (m.type.isErroneous())
3151 continue;
3152
3153 if (!membersWithDefault.contains(m))
3154 missingDefaults = missingDefaults.append(m.name);
3155 }
3156 missingDefaults = missingDefaults.reverse();
3157 if (missingDefaults.nonEmpty()) {
3158 isValid = false;
3159 String key = (missingDefaults.size() > 1)
3160 ? "annotation.missing.default.value.1"
3161 : "annotation.missing.default.value";
3162 log.error(a.pos(), key, a.type, missingDefaults);
3163 }
3164
3165 return isValid && validateTargetAnnotationValue(a);
3166 }
3167
3168 /* Validate the special java.lang.annotation.Target annotation */
3169 boolean validateTargetAnnotationValue(JCAnnotation a) {
3170 // special case: java.lang.annotation.Target must not have
3171 // repeated values in its value member
3172 if (a.annotationType.type.tsym != syms.annotationTargetType.tsym ||
3173 a.args.tail == null)
3174 return true;
3175
3176 boolean isValid = true;
3177 if (!a.args.head.hasTag(ASSIGN)) return false; // error recovery
3178 JCAssign assign = (JCAssign) a.args.head;
3179 Symbol m = TreeInfo.symbol(assign.lhs);
3180 if (m.name != names.value) return false;
3181 JCTree rhs = assign.rhs;
3182 if (!rhs.hasTag(NEWARRAY)) return false;
3183 JCNewArray na = (JCNewArray) rhs;
3184 Set<Symbol> targets = new HashSet<>();
3185 for (JCTree elem : na.elems) {
3186 if (!targets.add(TreeInfo.symbol(elem))) {
3187 isValid = false;
3188 log.error(elem.pos(), "repeated.annotation.target");
3189 }
3190 }
3191 return isValid;
3192 }
3193
3194 void checkDeprecatedAnnotation(DiagnosticPosition pos, Symbol s) {
3195 if (lint.isEnabled(LintCategory.DEP_ANN) &&
3196 (s.flags() & DEPRECATED) != 0 &&
3197 !syms.deprecatedType.isErroneous() &&
3198 s.attribute(syms.deprecatedType.tsym) == null) {
3199 log.warning(LintCategory.DEP_ANN,
3200 pos, "missing.deprecated.annotation");
3201 }
3202 // Note: @Deprecated has no effect on local variables, parameters and package decls.
3203 if (lint.isEnabled(LintCategory.DEPRECATION)) {
3204 if (!syms.deprecatedType.isErroneous() && s.attribute(syms.deprecatedType.tsym) != null) {
3205 switch (s.getKind()) {
3206 case LOCAL_VARIABLE:
3207 case PACKAGE:
3208 case PARAMETER:
3209 case RESOURCE_VARIABLE:
3210 case EXCEPTION_PARAMETER:
3211 log.warning(LintCategory.DEPRECATION, pos,
3212 "deprecated.annotation.has.no.effect", Kinds.kindName(s));
3213 break;
3214 }
3215 }
3216 }
3217 }
3218
3219 void checkDeprecated(final DiagnosticPosition pos, final Symbol other, final Symbol s) {
3220 if ((s.flags() & DEPRECATED) != 0 &&
3221 (other.flags() & DEPRECATED) == 0 &&
3222 s.outermostClass() != other.outermostClass()) {
3223 deferredLintHandler.report(new DeferredLintHandler.LintLogger() {
3224 @Override
3225 public void report() {
3226 warnDeprecated(pos, s);
3227 }
3228 });
3229 }
3230 }
3231
3232 void checkSunAPI(final DiagnosticPosition pos, final Symbol s) {
3233 if ((s.flags() & PROPRIETARY) != 0) {
3234 deferredLintHandler.report(() -> {
3235 log.mandatoryWarning(pos, "sun.proprietary", s);
3236 });
3237 }
3238 }
3239
3240 void checkProfile(final DiagnosticPosition pos, final Symbol s) {
3241 if (profile != Profile.DEFAULT && (s.flags() & NOT_IN_PROFILE) != 0) {
3242 log.error(pos, "not.in.profile", s, profile);
3243 }
3244 }
3245
3246 /* *************************************************************************
3247 * Check for recursive annotation elements.
3248 **************************************************************************/
3249
3250 /** Check for cycles in the graph of annotation elements.
3251 */
3252 void checkNonCyclicElements(JCClassDecl tree) {
3253 if ((tree.sym.flags_field & ANNOTATION) == 0) return;
3254 Assert.check((tree.sym.flags_field & LOCKED) == 0);
3255 try {
3256 tree.sym.flags_field |= LOCKED;
3257 for (JCTree def : tree.defs) {
3258 if (!def.hasTag(METHODDEF)) continue;
3259 JCMethodDecl meth = (JCMethodDecl)def;
3260 checkAnnotationResType(meth.pos(), meth.restype.type);
3261 }
3262 } finally {
3263 tree.sym.flags_field &= ~LOCKED;
3264 tree.sym.flags_field |= ACYCLIC_ANN;
3265 }
3266 }
3267
3268 void checkNonCyclicElementsInternal(DiagnosticPosition pos, TypeSymbol tsym) {
3269 if ((tsym.flags_field & ACYCLIC_ANN) != 0)
3270 return;
3271 if ((tsym.flags_field & LOCKED) != 0) {
3272 log.error(pos, "cyclic.annotation.element");
3273 return;
3274 }
3275 try {
3276 tsym.flags_field |= LOCKED;
3277 for (Symbol s : tsym.members().getSymbols(NON_RECURSIVE)) {
3278 if (s.kind != MTH)
3279 continue;
3280 checkAnnotationResType(pos, ((MethodSymbol)s).type.getReturnType());
3281 }
3282 } finally {
3283 tsym.flags_field &= ~LOCKED;
3284 tsym.flags_field |= ACYCLIC_ANN;
3285 }
3286 }
3287
3288 void checkAnnotationResType(DiagnosticPosition pos, Type type) {
3289 switch (type.getTag()) {
3290 case CLASS:
3291 if ((type.tsym.flags() & ANNOTATION) != 0)
3292 checkNonCyclicElementsInternal(pos, type.tsym);
3293 break;
3294 case ARRAY:
3295 checkAnnotationResType(pos, types.elemtype(type));
3296 break;
3297 default:
3298 break; // int etc
3299 }
3300 }
3301
3302 /* *************************************************************************
3303 * Check for cycles in the constructor call graph.
3304 **************************************************************************/
3305
3306 /** Check for cycles in the graph of constructors calling other
3307 * constructors.
3308 */
3309 void checkCyclicConstructors(JCClassDecl tree) {
3310 Map<Symbol,Symbol> callMap = new HashMap<>();
3311
3312 // enter each constructor this-call into the map
3313 for (List<JCTree> l = tree.defs; l.nonEmpty(); l = l.tail) {
3314 JCMethodInvocation app = TreeInfo.firstConstructorCall(l.head);
3315 if (app == null) continue;
3316 JCMethodDecl meth = (JCMethodDecl) l.head;
3317 if (TreeInfo.name(app.meth) == names._this) {
3318 callMap.put(meth.sym, TreeInfo.symbol(app.meth));
3319 } else {
3320 meth.sym.flags_field |= ACYCLIC;
3321 }
3322 }
3323
3324 // Check for cycles in the map
3325 Symbol[] ctors = new Symbol[0];
3326 ctors = callMap.keySet().toArray(ctors);
3327 for (Symbol caller : ctors) {
3328 checkCyclicConstructor(tree, caller, callMap);
3329 }
3330 }
3331
3332 /** Look in the map to see if the given constructor is part of a
3333 * call cycle.
3334 */
3335 private void checkCyclicConstructor(JCClassDecl tree, Symbol ctor,
3336 Map<Symbol,Symbol> callMap) {
3337 if (ctor != null && (ctor.flags_field & ACYCLIC) == 0) {
3338 if ((ctor.flags_field & LOCKED) != 0) {
3339 log.error(TreeInfo.diagnosticPositionFor(ctor, tree),
3340 "recursive.ctor.invocation");
3341 } else {
3342 ctor.flags_field |= LOCKED;
3343 checkCyclicConstructor(tree, callMap.remove(ctor), callMap);
3344 ctor.flags_field &= ~LOCKED;
3345 }
3346 ctor.flags_field |= ACYCLIC;
3347 }
3348 }
3349
3350 /* *************************************************************************
3351 * Miscellaneous
3352 **************************************************************************/
3353
3354 /**
3355 * Check for division by integer constant zero
3356 * @param pos Position for error reporting.
3357 * @param operator The operator for the expression
3358 * @param operand The right hand operand for the expression
3359 */
3360 void checkDivZero(final DiagnosticPosition pos, Symbol operator, Type operand) {
3361 if (operand.constValue() != null
3362 && operand.getTag().isSubRangeOf(LONG)
3363 && ((Number) (operand.constValue())).longValue() == 0) {
3364 int opc = ((OperatorSymbol)operator).opcode;
3365 if (opc == ByteCodes.idiv || opc == ByteCodes.imod
3366 || opc == ByteCodes.ldiv || opc == ByteCodes.lmod) {
3367 deferredLintHandler.report(new DeferredLintHandler.LintLogger() {
3368 @Override
3369 public void report() {
3370 warnDivZero(pos);
3371 }
3372 });
3373 }
3374 }
3375 }
3376
3377 /**
3378 * Check for empty statements after if
3379 */
3380 void checkEmptyIf(JCIf tree) {
3381 if (tree.thenpart.hasTag(SKIP) && tree.elsepart == null &&
3382 lint.isEnabled(LintCategory.EMPTY))
3383 log.warning(LintCategory.EMPTY, tree.thenpart.pos(), "empty.if");
3384 }
3385
3386 /** Check that symbol is unique in given scope.
3387 * @param pos Position for error reporting.
3388 * @param sym The symbol.
3389 * @param s The scope.
3390 */
3391 boolean checkUnique(DiagnosticPosition pos, Symbol sym, Scope s) {
3392 if (sym.type.isErroneous())
3393 return true;
3394 if (sym.owner.name == names.any) return false;
3395 for (Symbol byName : s.getSymbolsByName(sym.name, NON_RECURSIVE)) {
3396 if (sym != byName &&
3397 (byName.flags() & CLASH) == 0 &&
3398 sym.kind == byName.kind &&
3399 sym.name != names.error &&
3400 (sym.kind != MTH ||
3401 types.hasSameArgs(sym.type, byName.type) ||
3402 types.hasSameArgs(types.erasure(sym.type), types.erasure(byName.type)))) {
3403 if ((sym.flags() & VARARGS) != (byName.flags() & VARARGS)) {
3404 varargsDuplicateError(pos, sym, byName);
3405 return true;
3406 } else if (sym.kind == MTH && !types.hasSameArgs(sym.type, byName.type, false)) {
3407 duplicateErasureError(pos, sym, byName);
3408 sym.flags_field |= CLASH;
3409 return true;
3410 } else {
3411 duplicateError(pos, byName);
3412 return false;
3413 }
3414 }
3415 }
3416 return true;
3417 }
3418
3419 /** Report duplicate declaration error.
3420 */
3421 void duplicateErasureError(DiagnosticPosition pos, Symbol sym1, Symbol sym2) {
3422 if (!sym1.type.isErroneous() && !sym2.type.isErroneous()) {
3423 log.error(pos, "name.clash.same.erasure", sym1, sym2);
3424 }
3425 }
3426
3427 /**Check that types imported through the ordinary imports don't clash with types imported
3428 * by other (static or ordinary) imports. Note that two static imports may import two clashing
3429 * types without an error on the imports.
3430 * @param toplevel The toplevel tree for which the test should be performed.
3431 */
3432 void checkImportsUnique(JCCompilationUnit toplevel) {
3433 WriteableScope ordinallyImportedSoFar = WriteableScope.create(toplevel.packge);
3434 WriteableScope staticallyImportedSoFar = WriteableScope.create(toplevel.packge);
3435 WriteableScope topLevelScope = toplevel.toplevelScope;
3436
3437 for (JCTree def : toplevel.defs) {
3438 if (!def.hasTag(IMPORT))
3439 continue;
3440
3441 JCImport imp = (JCImport) def;
3442
3443 if (imp.importScope == null)
3444 continue;
3445
3446 for (Symbol sym : imp.importScope.getSymbols(sym -> sym.kind == TYP)) {
3447 if (imp.isStatic()) {
3448 checkUniqueImport(imp.pos(), ordinallyImportedSoFar, staticallyImportedSoFar, topLevelScope, sym, true);
3449 staticallyImportedSoFar.enter(sym);
3450 } else {
3451 checkUniqueImport(imp.pos(), ordinallyImportedSoFar, staticallyImportedSoFar, topLevelScope, sym, false);
3452 ordinallyImportedSoFar.enter(sym);
3453 }
3454 }
3455
3456 imp.importScope = null;
3457 }
3458 }
3459
3460 /** Check that single-type import is not already imported or top-level defined,
3461 * but make an exception for two single-type imports which denote the same type.
3462 * @param pos Position for error reporting.
3463 * @param ordinallyImportedSoFar A Scope containing types imported so far through
3464 * ordinary imports.
3465 * @param staticallyImportedSoFar A Scope containing types imported so far through
3466 * static imports.
3467 * @param topLevelScope The current file's top-level Scope
3468 * @param sym The symbol.
3469 * @param staticImport Whether or not this was a static import
3470 */
3471 private boolean checkUniqueImport(DiagnosticPosition pos, Scope ordinallyImportedSoFar,
3472 Scope staticallyImportedSoFar, Scope topLevelScope,
3473 Symbol sym, boolean staticImport) {
3474 Filter<Symbol> duplicates = candidate -> candidate != sym && !candidate.type.isErroneous();
3475 Symbol clashing = ordinallyImportedSoFar.findFirst(sym.name, duplicates);
3476 if (clashing == null && !staticImport) {
3477 clashing = staticallyImportedSoFar.findFirst(sym.name, duplicates);
3478 }
3479 if (clashing != null) {
3480 if (staticImport)
3481 log.error(pos, "already.defined.static.single.import", clashing);
3482 else
3483 log.error(pos, "already.defined.single.import", clashing);
3484 return false;
3485 }
3486 clashing = topLevelScope.findFirst(sym.name, duplicates);
3487 if (clashing != null) {
3488 log.error(pos, "already.defined.this.unit", clashing);
3489 return false;
3490 }
3491 return true;
3492 }
3493
3494 /** Check that a qualified name is in canonical form (for import decls).
3495 */
3496 public void checkCanonical(JCTree tree) {
3497 if (!isCanonical(tree))
3498 log.error(tree.pos(), "import.requires.canonical",
3499 TreeInfo.symbol(tree));
3500 }
3501 // where
3502 private boolean isCanonical(JCTree tree) {
3503 while (tree.hasTag(SELECT)) {
3504 JCFieldAccess s = (JCFieldAccess) tree;
3505 if (s.sym.owner.name != TreeInfo.symbol(s.selected).name)
3506 return false;
3507 tree = s.selected;
3508 }
3509 return true;
3510 }
3511
3512 /** Check that an auxiliary class is not accessed from any other file than its own.
3513 */
3514 void checkForBadAuxiliaryClassAccess(DiagnosticPosition pos, Env<AttrContext> env, ClassSymbol c) {
3515 if (lint.isEnabled(Lint.LintCategory.AUXILIARYCLASS) &&
3516 (c.flags() & AUXILIARY) != 0 &&
3517 rs.isAccessible(env, c) &&
3518 !fileManager.isSameFile(c.sourcefile, env.toplevel.sourcefile))
3519 {
3520 log.warning(pos, "auxiliary.class.accessed.from.outside.of.its.source.file",
3521 c, c.sourcefile);
3522 }
3523 }
3524
3525 private class ConversionWarner extends Warner {
3526 final String uncheckedKey;
3527 final Type found;
3528 final Type expected;
3529 public ConversionWarner(DiagnosticPosition pos, String uncheckedKey, Type found, Type expected) {
3530 super(pos);
3531 this.uncheckedKey = uncheckedKey;
3532 this.found = found;
3533 this.expected = expected;
3534 }
3535
3536 @Override
3537 public void warn(LintCategory lint) {
3538 boolean warned = this.warned;
3539 super.warn(lint);
3540 if (warned) return; // suppress redundant diagnostics
3541 switch (lint) {
3542 case UNCHECKED:
3543 Check.this.warnUnchecked(pos(), "prob.found.req", diags.fragment(uncheckedKey), found, expected);
3544 break;
3545 case VARARGS:
3546 if (method != null &&
3547 method.attribute(syms.trustMeType.tsym) != null &&
3548 isTrustMeAllowedOnMethod(method) &&
3549 !types.isReifiable(method.type.getParameterTypes().last())) {
3550 Check.this.warnUnsafeVararg(pos(), "varargs.unsafe.use.varargs.param", method.params.last());
3551 }
3552 break;
3553 default:
3554 throw new AssertionError("Unexpected lint: " + lint);
3555 }
3556 }
3557 }
3558
3559 public Warner castWarner(DiagnosticPosition pos, Type found, Type expected) {
3560 return new ConversionWarner(pos, "unchecked.cast.to.type", found, expected);
3561 }
3562
3563 public Warner convertWarner(DiagnosticPosition pos, Type found, Type expected) {
3564 return new ConversionWarner(pos, "unchecked.assign", found, expected);
3565 }
3566
3567 public void checkFunctionalInterface(JCClassDecl tree, ClassSymbol cs) {
3568 Compound functionalType = cs.attribute(syms.functionalInterfaceType.tsym);
3569
3570 if (functionalType != null) {
3571 try {
3572 types.findDescriptorSymbol((TypeSymbol)cs);
3573 } catch (Types.FunctionDescriptorLookupError ex) {
3574 DiagnosticPosition pos = tree.pos();
3575 for (JCAnnotation a : tree.getModifiers().annotations) {
3576 if (a.annotationType.type.tsym == syms.functionalInterfaceType.tsym) {
3577 pos = a.pos();
3578 break;
3579 }
3580 }
3581 log.error(pos, "bad.functional.intf.anno.1", ex.getDiagnostic());
3582 }
3583 }
3584 }
3585
3586 public void checkImportsResolvable(final JCCompilationUnit toplevel) {
3587 for (final JCImport imp : toplevel.getImports()) {
3588 if (!imp.staticImport || !imp.qualid.hasTag(SELECT))
3589 continue;
3590 final JCFieldAccess select = (JCFieldAccess) imp.qualid;
3591 final Symbol origin;
3592 if (select.name == names.asterisk || (origin = TreeInfo.symbol(select.selected)) == null || origin.kind != TYP)
3593 continue;
3594
3595 TypeSymbol site = (TypeSymbol) TreeInfo.symbol(select.selected);
3596 if (!checkTypeContainsImportableElement(site, site, toplevel.packge, select.name, new HashSet<Symbol>())) {
3597 log.error(imp.pos(), "cant.resolve.location",
3598 KindName.STATIC,
3599 select.name, List.<Type>nil(), List.<Type>nil(),
3600 Kinds.typeKindName(TreeInfo.symbol(select.selected).type),
3601 TreeInfo.symbol(select.selected).type);
3602 }
3603 }
3604 }
3605
3606 // Check that packages imported are in scope (JLS 7.4.3, 6.3, 6.5.3.1, 6.5.3.2)
3607 public void checkImportedPackagesObservable(final JCCompilationUnit toplevel) {
3608 OUTER: for (JCImport imp : toplevel.getImports()) {
3609 if (!imp.staticImport && TreeInfo.name(imp.qualid) == names.asterisk) {
3610 TypeSymbol tsym = ((JCFieldAccess)imp.qualid).selected.type.tsym;
3611 if (toplevel.modle.visiblePackages != null) {
3612 //TODO - unclear: selects like javax.* will get resolved from the current module
3613 //(as javax is not an exported package from any module). And as javax in the current
3614 //module typically does not contain any classes or subpackages, we need to go through
3615 //the visible packages to find a sub-package:
3616 for (PackageSymbol known : toplevel.modle.visiblePackages.values()) {
3617 if (Convert.packagePart(known.fullname) == tsym.flatName())
3618 continue OUTER;
3619 }
3620 }
3621 if (tsym.kind == PCK && tsym.members().isEmpty() && !tsym.exists()) {
3622 log.error(DiagnosticFlag.RESOLVE_ERROR, imp.pos, "doesnt.exist", tsym);
3623 }
3624 }
3625 }
3626 }
3627
3628 private boolean checkTypeContainsImportableElement(TypeSymbol tsym, TypeSymbol origin, PackageSymbol packge, Name name, Set<Symbol> processed) {
3629 if (tsym == null || !processed.add(tsym))
3630 return false;
3631
3632 // also search through inherited names
3633 if (checkTypeContainsImportableElement(types.supertype(tsym.type).tsym, origin, packge, name, processed))
3634 return true;
3635
3636 for (Type t : types.interfaces(tsym.type))
3637 if (checkTypeContainsImportableElement(t.tsym, origin, packge, name, processed))
3638 return true;
3639
3640 for (Symbol sym : tsym.members().getSymbolsByName(name)) {
3641 if (sym.isStatic() &&
3642 importAccessible(sym, packge) &&
3643 sym.isMemberOf(origin, types)) {
3644 return true;
3645 }
3646 }
3647
3648 return false;
3649 }
3650
3651 // is the sym accessible everywhere in packge?
3652 public boolean importAccessible(Symbol sym, PackageSymbol packge) {
3653 try {
3654 int flags = (int)(sym.flags() & AccessFlags);
3655 switch (flags) {
3656 default:
3657 case PUBLIC:
3658 return true;
3659 case PRIVATE:
3660 return false;
3661 case 0:
3662 case PROTECTED:
3663 return sym.packge() == packge;
3664 }
3665 } catch (ClassFinder.BadClassFile err) {
3666 throw err;
3667 } catch (CompletionFailure ex) {
3668 return false;
3669 }
3670 }
3671
3672 }