1 /*
2 * Copyright (c) 1999, 2015, Oracle and/or its affiliates. All rights reserved.
3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
4 *
5 * This code is free software; you can redistribute it and/or modify it
6 * under the terms of the GNU General Public License version 2 only, as
7 * published by the Free Software Foundation. Oracle designates this
8 * particular file as subject to the "Classpath" exception as provided
9 * by Oracle in the LICENSE file that accompanied this code.
10 *
11 * This code is distributed in the hope that it will be useful, but WITHOUT
12 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
13 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
14 * version 2 for more details (a copy is included in the LICENSE file that
15 * accompanied this code).
16 *
17 * You should have received a copy of the GNU General Public License version
18 * 2 along with this work; if not, write to the Free Software Foundation,
19 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
20 *
21 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
22 * or visit www.oracle.com if you need additional information or have any
23 * questions.
24 */
25
26 package com.sun.tools.javac.comp;
27
28 import java.util.*;
29
30 import javax.tools.JavaFileManager;
31
32 import com.sun.tools.javac.code.*;
33 import com.sun.tools.javac.code.Attribute.Compound;
34 import com.sun.tools.javac.jvm.*;
35 import com.sun.tools.javac.tree.*;
36 import com.sun.tools.javac.util.*;
37 import com.sun.tools.javac.util.JCDiagnostic.DiagnosticPosition;
38 import com.sun.tools.javac.util.List;
39
40 import com.sun.tools.javac.code.Lint;
41 import com.sun.tools.javac.code.Lint.LintCategory;
42 import com.sun.tools.javac.code.Scope.CompoundScope;
43 import com.sun.tools.javac.code.Scope.NamedImportScope;
44 import com.sun.tools.javac.code.Scope.WriteableScope;
45 import com.sun.tools.javac.code.Type.*;
46 import com.sun.tools.javac.code.Symbol.*;
47 import com.sun.tools.javac.comp.DeferredAttr.DeferredAttrContext;
48 import com.sun.tools.javac.comp.Infer.InferenceContext;
49 import com.sun.tools.javac.comp.Infer.FreeTypeListener;
50 import com.sun.tools.javac.tree.JCTree.*;
51 import com.sun.tools.javac.tree.JCTree.JCPolyExpression.*;
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 JCDiagnostic.Factory diags;
83 private boolean warnOnSyntheticConflicts;
84 private boolean suppressAbortOnBadClassFile;
85 private boolean enableSunApiLintControl;
86 private final JavaFileManager fileManager;
87 private final Profile profile;
88 private final boolean warnOnAccessToSensitiveMembers;
89
90 // The set of lint options currently in effect. It is initialized
91 // from the context, and then is set/reset as needed by Attr as it
92 // visits all the various parts of the trees during attribution.
93 private Lint lint;
94
95 // The method being analyzed in Attr - it is set/reset as needed by
96 // Attr as it visits new method declarations.
97 private MethodSymbol method;
98
99 public static Check instance(Context context) {
100 Check instance = context.get(checkKey);
101 if (instance == null)
102 instance = new Check(context);
103 return instance;
104 }
105
106 protected Check(Context context) {
107 context.put(checkKey, this);
108
109 names = Names.instance(context);
110 dfltTargetMeta = new Name[] { names.PACKAGE, names.TYPE,
111 names.FIELD, names.METHOD, names.CONSTRUCTOR,
112 names.ANNOTATION_TYPE, names.LOCAL_VARIABLE, names.PARAMETER};
113 log = Log.instance(context);
114 rs = Resolve.instance(context);
115 syms = Symtab.instance(context);
116 enter = Enter.instance(context);
117 deferredAttr = DeferredAttr.instance(context);
118 infer = Infer.instance(context);
119 types = Types.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 = Source.instance(context);
126 allowSimplifiedVarargs = source.allowSimplifiedVarargs();
127 allowDefaultMethods = source.allowDefaultMethods();
128 allowStrictMethodClashCheck = source.allowStrictMethodClashCheck();
129 allowPrivateSafeVarargs = source.allowPrivateSafeVarargs();
130 complexInference = options.isSet("complexinference");
131 warnOnSyntheticConflicts = options.isSet("warnOnSyntheticConflicts");
132 suppressAbortOnBadClassFile = options.isSet("suppressAbortOnBadClassFile");
133 enableSunApiLintControl = options.isSet("enableSunApiLintControl");
134 warnOnAccessToSensitiveMembers = options.isSet("warnOnAccessToSensitiveMembers");
135
136 Target target = Target.instance(context);
137 syntheticNameChar = target.syntheticNameChar();
138
139 profile = Profile.instance(context);
140
141 boolean verboseDeprecated = lint.isEnabled(LintCategory.DEPRECATION);
142 boolean verboseUnchecked = lint.isEnabled(LintCategory.UNCHECKED);
143 boolean verboseSunApi = lint.isEnabled(LintCategory.SUNAPI);
144 boolean enforceMandatoryWarnings = true;
145
146 deprecationHandler = new MandatoryWarningHandler(log, verboseDeprecated,
147 enforceMandatoryWarnings, "deprecated", LintCategory.DEPRECATION);
148 uncheckedHandler = new MandatoryWarningHandler(log, verboseUnchecked,
149 enforceMandatoryWarnings, "unchecked", LintCategory.UNCHECKED);
150 sunApiHandler = new MandatoryWarningHandler(log, verboseSunApi,
151 enforceMandatoryWarnings, "sunapi", null);
152
153 deferredLintHandler = DeferredLintHandler.instance(context);
154 }
155
156 /** Switch: simplified varargs enabled?
157 */
158 boolean allowSimplifiedVarargs;
159
160 /** Switch: default methods enabled?
161 */
162 boolean allowDefaultMethods;
163
164 /** Switch: should unrelated return types trigger a method clash?
165 */
166 boolean allowStrictMethodClashCheck;
167
168 /** Switch: can the @SafeVarargs annotation be applied to private methods?
169 */
170 boolean allowPrivateSafeVarargs;
171
172 /** Switch: -complexinference option set?
173 */
174 boolean complexInference;
175
176 /** Character for synthetic names
177 */
178 char syntheticNameChar;
179
180 /** A table mapping flat names of all compiled classes in this run to their
181 * symbols; maintained from outside.
182 */
183 public Map<Name,ClassSymbol> compiled = new HashMap<>();
184
185 /** A handler for messages about deprecated usage.
186 */
187 private MandatoryWarningHandler deprecationHandler;
188
189 /** A handler for messages about unchecked or unsafe usage.
190 */
191 private MandatoryWarningHandler uncheckedHandler;
192
193 /** A handler for messages about using proprietary API.
194 */
195 private MandatoryWarningHandler sunApiHandler;
196
197 /** A handler for deferred lint warnings.
198 */
199 private DeferredLintHandler deferredLintHandler;
200
201 /* *************************************************************************
202 * Errors and Warnings
203 **************************************************************************/
204
205 Lint setLint(Lint newLint) {
206 Lint prev = lint;
207 lint = newLint;
208 return prev;
209 }
210
211 MethodSymbol setMethod(MethodSymbol newMethod) {
212 MethodSymbol prev = method;
213 method = newMethod;
214 return prev;
215 }
216
217 /** Warn about deprecated symbol.
218 * @param pos Position to be used for error reporting.
219 * @param sym The deprecated symbol.
220 */
221 void warnDeprecated(DiagnosticPosition pos, Symbol sym) {
222 if (!lint.isSuppressed(LintCategory.DEPRECATION))
223 deprecationHandler.report(pos, "has.been.deprecated", sym, sym.location());
224 }
225
226 /** Warn about unchecked operation.
227 * @param pos Position to be used for error reporting.
228 * @param msg A string describing the problem.
229 */
230 public void warnUnchecked(DiagnosticPosition pos, String msg, Object... args) {
231 if (!lint.isSuppressed(LintCategory.UNCHECKED))
232 uncheckedHandler.report(pos, msg, args);
233 }
234
235 /** Warn about unsafe vararg method decl.
236 * @param pos Position to be used for error reporting.
237 */
238 void warnUnsafeVararg(DiagnosticPosition pos, String key, Object... args) {
239 if (lint.isEnabled(LintCategory.VARARGS) && allowSimplifiedVarargs)
240 log.warning(LintCategory.VARARGS, pos, key, args);
241 }
242
243 /** Warn about using proprietary API.
244 * @param pos Position to be used for error reporting.
245 * @param msg A string describing the problem.
246 */
247 public void warnSunApi(DiagnosticPosition pos, String msg, Object... args) {
248 if (!lint.isSuppressed(LintCategory.SUNAPI))
249 sunApiHandler.report(pos, msg, args);
250 }
251
252 public void warnStatic(DiagnosticPosition pos, String msg, Object... args) {
253 if (lint.isEnabled(LintCategory.STATIC))
254 log.warning(LintCategory.STATIC, pos, msg, args);
255 }
256
257 /** Warn about division by integer constant zero.
258 * @param pos Position to be used for error reporting.
259 */
260 void warnDivZero(DiagnosticPosition pos) {
261 if (lint.isEnabled(LintCategory.DIVZERO))
262 log.warning(LintCategory.DIVZERO, pos, "div.zero");
263 }
264
265 /**
266 * Report any deferred diagnostics.
267 */
268 public void reportDeferredDiagnostics() {
269 deprecationHandler.reportDeferredDiagnostic();
270 uncheckedHandler.reportDeferredDiagnostic();
271 sunApiHandler.reportDeferredDiagnostic();
272 }
273
274
275 /** Report a failure to complete a class.
276 * @param pos Position to be used for error reporting.
277 * @param ex The failure to report.
278 */
279 public Type completionError(DiagnosticPosition pos, CompletionFailure ex) {
280 log.error(JCDiagnostic.DiagnosticFlag.NON_DEFERRABLE, pos, "cant.access", ex.sym, ex.getDetailValue());
281 if (ex instanceof ClassFinder.BadClassFile
282 && !suppressAbortOnBadClassFile) throw new Abort();
283 else return syms.errType;
284 }
285
286 /** Report an error that wrong type tag was found.
287 * @param pos Position to be used for error reporting.
288 * @param required An internationalized string describing the type tag
289 * required.
290 * @param found The type that was found.
291 */
292 Type typeTagError(DiagnosticPosition pos, Object required, Object found) {
293 // this error used to be raised by the parser,
294 // but has been delayed to this point:
295 if (found instanceof Type && ((Type)found).hasTag(VOID)) {
296 log.error(pos, "illegal.start.of.type");
297 return syms.errType;
298 }
299 log.error(pos, "type.found.req", found, required);
300 return types.createErrorType(found instanceof Type ? (Type)found : syms.errType);
301 }
302
303 /** Report an error that symbol cannot be referenced before super
304 * has been called.
305 * @param pos Position to be used for error reporting.
306 * @param sym The referenced symbol.
307 */
308 void earlyRefError(DiagnosticPosition pos, Symbol sym) {
309 log.error(pos, "cant.ref.before.ctor.called", sym);
310 }
311
312 /** Report duplicate declaration error.
313 */
314 void duplicateError(DiagnosticPosition pos, Symbol sym) {
315 if (!sym.type.isErroneous()) {
316 Symbol location = sym.location();
317 if (location.kind == MTH &&
318 ((MethodSymbol)location).isStaticOrInstanceInit()) {
319 log.error(pos, "already.defined.in.clinit", kindName(sym), sym,
320 kindName(sym.location()), kindName(sym.location().enclClass()),
321 sym.location().enclClass());
322 } else {
323 log.error(pos, "already.defined", kindName(sym), sym,
324 kindName(sym.location()), sym.location());
325 }
326 }
327 }
328
329 /** Report array/varargs duplicate declaration
330 */
331 void varargsDuplicateError(DiagnosticPosition pos, Symbol sym1, Symbol sym2) {
332 if (!sym1.type.isErroneous() && !sym2.type.isErroneous()) {
333 log.error(pos, "array.and.varargs", sym1, sym2, sym2.location());
334 }
335 }
336
337 /* ************************************************************************
338 * duplicate declaration checking
339 *************************************************************************/
340
341 /** Check that variable does not hide variable with same name in
342 * immediately enclosing local scope.
343 * @param pos Position for error reporting.
344 * @param v The symbol.
345 * @param s The scope.
346 */
347 void checkTransparentVar(DiagnosticPosition pos, VarSymbol v, Scope s) {
348 for (Symbol sym : s.getSymbolsByName(v.name)) {
349 if (sym.owner != v.owner) break;
350 if (sym.kind == VAR &&
351 sym.owner.kind.matches(KindSelector.VAL_MTH) &&
352 v.name != names.error) {
353 duplicateError(pos, sym);
354 return;
355 }
356 }
357 }
358
359 /** Check that a class or interface does not hide a class or
360 * interface with same name in immediately enclosing local scope.
361 * @param pos Position for error reporting.
362 * @param c The symbol.
363 * @param s The scope.
364 */
365 void checkTransparentClass(DiagnosticPosition pos, ClassSymbol c, Scope s) {
366 for (Symbol sym : s.getSymbolsByName(c.name)) {
367 if (sym.owner != c.owner) break;
368 if (sym.kind == TYP && !sym.type.hasTag(TYPEVAR) &&
369 sym.owner.kind.matches(KindSelector.VAL_MTH) &&
370 c.name != names.error) {
371 duplicateError(pos, sym);
372 return;
373 }
374 }
375 }
376
377 /** Check that class does not have the same name as one of
378 * its enclosing classes, or as a class defined in its enclosing scope.
379 * return true if class is unique in its enclosing scope.
380 * @param pos Position for error reporting.
381 * @param name The class name.
382 * @param s The enclosing scope.
383 */
384 boolean checkUniqueClassName(DiagnosticPosition pos, Name name, Scope s) {
385 for (Symbol sym : s.getSymbolsByName(name, NON_RECURSIVE)) {
386 if (sym.kind == TYP && sym.name != names.error) {
387 duplicateError(pos, sym);
388 return false;
389 }
390 }
391 for (Symbol sym = s.owner; sym != null; sym = sym.owner) {
392 if (sym.kind == TYP && sym.name == name && sym.name != names.error) {
393 duplicateError(pos, sym);
394 return true;
395 }
396 }
397 return true;
398 }
399
400 /* *************************************************************************
401 * Class name generation
402 **************************************************************************/
403
404 /** Return name of local class.
405 * This is of the form {@code <enclClass> $ n <classname> }
406 * where
407 * enclClass is the flat name of the enclosing class,
408 * classname is the simple name of the local class
409 */
410 Name localClassName(ClassSymbol c) {
411 for (int i=1; ; i++) {
412 Name flatname = names.
413 fromString("" + c.owner.enclClass().flatname +
414 syntheticNameChar + i +
415 c.name);
416 if (compiled.get(flatname) == null) return flatname;
417 }
418 }
419
420 public void newRound() {
421 compiled.clear();
422 }
423
424 /* *************************************************************************
425 * Type Checking
426 **************************************************************************/
427
428 /**
429 * A check context is an object that can be used to perform compatibility
430 * checks - depending on the check context, meaning of 'compatibility' might
431 * vary significantly.
432 */
433 public interface CheckContext {
434 /**
435 * Is type 'found' compatible with type 'req' in given context
436 */
437 boolean compatible(Type found, Type req, Warner warn);
438 /**
439 * Report a check error
440 */
441 void report(DiagnosticPosition pos, JCDiagnostic details);
442 /**
443 * Obtain a warner for this check context
444 */
445 public Warner checkWarner(DiagnosticPosition pos, Type found, Type req);
446
447 public Infer.InferenceContext inferenceContext();
448
449 public DeferredAttr.DeferredAttrContext deferredAttrContext();
450 }
451
452 /**
453 * This class represent a check context that is nested within another check
454 * context - useful to check sub-expressions. The default behavior simply
455 * redirects all method calls to the enclosing check context leveraging
456 * the forwarding pattern.
457 */
458 static class NestedCheckContext implements CheckContext {
459 CheckContext enclosingContext;
460
461 NestedCheckContext(CheckContext enclosingContext) {
462 this.enclosingContext = enclosingContext;
463 }
464
465 public boolean compatible(Type found, Type req, Warner warn) {
466 return enclosingContext.compatible(found, req, warn);
467 }
468
469 public void report(DiagnosticPosition pos, JCDiagnostic details) {
470 enclosingContext.report(pos, details);
471 }
472
473 public Warner checkWarner(DiagnosticPosition pos, Type found, Type req) {
474 return enclosingContext.checkWarner(pos, found, req);
475 }
476
477 public Infer.InferenceContext inferenceContext() {
478 return enclosingContext.inferenceContext();
479 }
480
481 public DeferredAttrContext deferredAttrContext() {
482 return enclosingContext.deferredAttrContext();
483 }
484 }
485
486 /**
487 * Check context to be used when evaluating assignment/return statements
488 */
489 CheckContext basicHandler = new CheckContext() {
490 public void report(DiagnosticPosition pos, JCDiagnostic details) {
491 log.error(pos, "prob.found.req", details);
492 }
493 public boolean compatible(Type found, Type req, Warner warn) {
494 return types.isAssignable(found, req, warn);
495 }
496
497 public Warner checkWarner(DiagnosticPosition pos, Type found, Type req) {
498 return convertWarner(pos, found, req);
499 }
500
501 public InferenceContext inferenceContext() {
502 return infer.emptyContext;
503 }
504
505 public DeferredAttrContext deferredAttrContext() {
506 return deferredAttr.emptyDeferredAttrContext;
507 }
508
509 @Override
510 public String toString() {
511 return "CheckContext: basicHandler";
512 }
513 };
514
515 /** Check that a given type is assignable to a given proto-type.
516 * If it is, return the type, otherwise return errType.
517 * @param pos Position to be used for error reporting.
518 * @param found The type that was found.
519 * @param req The type that was required.
520 */
521 Type checkType(DiagnosticPosition pos, Type found, Type req) {
522 return checkType(pos, found, req, basicHandler);
523 }
524
525 Type checkType(final DiagnosticPosition pos, final Type found, final Type req, final CheckContext checkContext) {
526 final Infer.InferenceContext inferenceContext = checkContext.inferenceContext();
527 if (inferenceContext.free(req) || inferenceContext.free(found)) {
528 inferenceContext.addFreeTypeListener(List.of(req, found), new FreeTypeListener() {
529 @Override
530 public void typesInferred(InferenceContext inferenceContext) {
531 checkType(pos, inferenceContext.asInstType(found), inferenceContext.asInstType(req), checkContext);
532 }
533 });
534 }
535 if (req.hasTag(ERROR))
536 return req;
537 if (req.hasTag(NONE))
538 return found;
539 if (checkContext.compatible(found, req, checkContext.checkWarner(pos, found, req))) {
540 return found;
541 } else {
542 if (found.isNumeric() && req.isNumeric()) {
543 checkContext.report(pos, diags.fragment("possible.loss.of.precision", found, req));
544 return types.createErrorType(found);
545 }
546 checkContext.report(pos, diags.fragment("inconvertible.types", found, req));
547 return types.createErrorType(found);
548 }
549 }
550
551 /** Check that a given type can be cast to a given target type.
552 * Return the result of the cast.
553 * @param pos Position to be used for error reporting.
554 * @param found The type that is being cast.
555 * @param req The target type of the cast.
556 */
557 Type checkCastable(DiagnosticPosition pos, Type found, Type req) {
558 return checkCastable(pos, found, req, basicHandler);
559 }
560 Type checkCastable(DiagnosticPosition pos, Type found, Type req, CheckContext checkContext) {
561 if (types.isCastable(found, req, castWarner(pos, found, req))) {
562 return req;
563 } else {
564 checkContext.report(pos, diags.fragment("inconvertible.types", found, req));
565 return types.createErrorType(found);
566 }
567 }
568
569 /** Check for redundant casts (i.e. where source type is a subtype of target type)
570 * The problem should only be reported for non-292 cast
571 */
572 public void checkRedundantCast(Env<AttrContext> env, final JCTypeCast tree) {
573 if (!tree.type.isErroneous()
574 && types.isSameType(tree.expr.type, tree.clazz.type)
575 && !(ignoreAnnotatedCasts && TreeInfo.containsTypeAnnotation(tree.clazz))
576 && !is292targetTypeCast(tree)) {
577 deferredLintHandler.report(new DeferredLintHandler.LintLogger() {
578 @Override
579 public void report() {
580 if (lint.isEnabled(Lint.LintCategory.CAST))
581 log.warning(Lint.LintCategory.CAST,
582 tree.pos(), "redundant.cast", tree.expr.type);
583 }
584 });
585 }
586 }
587 //where
588 private boolean is292targetTypeCast(JCTypeCast tree) {
589 boolean is292targetTypeCast = false;
590 JCExpression expr = TreeInfo.skipParens(tree.expr);
591 if (expr.hasTag(APPLY)) {
592 JCMethodInvocation apply = (JCMethodInvocation)expr;
593 Symbol sym = TreeInfo.symbol(apply.meth);
594 is292targetTypeCast = sym != null &&
595 sym.kind == MTH &&
596 (sym.flags() & HYPOTHETICAL) != 0;
597 }
598 return is292targetTypeCast;
599 }
600
601 private static final boolean ignoreAnnotatedCasts = true;
602
603 /** Check that a type is within some bounds.
604 *
605 * Used in TypeApply to verify that, e.g., X in {@code V<X>} is a valid
606 * type argument.
607 * @param a The type that should be bounded by bs.
608 * @param bound The bound.
609 */
610 private boolean checkExtends(Type a, Type bound) {
611 if (a.isUnbound()) {
612 return true;
613 } else if (!a.hasTag(WILDCARD)) {
614 a = types.cvarUpperBound(a);
615 return types.isSubtype(a, bound);
616 } else if (a.isExtendsBound()) {
617 return types.isCastable(bound, types.wildUpperBound(a), types.noWarnings);
618 } else if (a.isSuperBound()) {
619 return !types.notSoftSubtype(types.wildLowerBound(a), bound);
620 }
621 return true;
622 }
623
624 /** Check that type is different from 'void'.
625 * @param pos Position to be used for error reporting.
626 * @param t The type to be checked.
627 */
628 Type checkNonVoid(DiagnosticPosition pos, Type t) {
629 if (t.hasTag(VOID)) {
630 log.error(pos, "void.not.allowed.here");
631 return types.createErrorType(t);
632 } else {
633 return t;
634 }
635 }
636
637 Type checkClassOrArrayType(DiagnosticPosition pos, Type t) {
638 if (!t.hasTag(CLASS) && !t.hasTag(ARRAY) && !t.hasTag(ERROR)) {
639 return typeTagError(pos,
640 diags.fragment("type.req.class.array"),
641 asTypeParam(t));
642 } else {
643 return t;
644 }
645 }
646
647 /** Check that type is a class or interface type.
648 * @param pos Position to be used for error reporting.
649 * @param t The type to be checked.
650 */
651 Type checkClassType(DiagnosticPosition pos, Type t) {
652 if (!t.hasTag(CLASS) && !t.hasTag(ERROR)) {
653 return typeTagError(pos,
654 diags.fragment("type.req.class"),
655 asTypeParam(t));
656 } else {
657 return t;
658 }
659 }
660 //where
661 private Object asTypeParam(Type t) {
662 return (t.hasTag(TYPEVAR))
663 ? diags.fragment("type.parameter", t)
664 : t;
665 }
666
667 /** Check that type is a valid qualifier for a constructor reference expression
668 */
669 Type checkConstructorRefType(DiagnosticPosition pos, Type t) {
670 t = checkClassOrArrayType(pos, t);
671 if (t.hasTag(CLASS)) {
672 if ((t.tsym.flags() & (ABSTRACT | INTERFACE)) != 0) {
673 log.error(pos, "abstract.cant.be.instantiated", t.tsym);
674 t = types.createErrorType(t);
675 } else if ((t.tsym.flags() & ENUM) != 0) {
676 log.error(pos, "enum.cant.be.instantiated");
677 t = types.createErrorType(t);
678 } else {
679 t = checkClassType(pos, t, true);
680 }
681 } else if (t.hasTag(ARRAY)) {
682 if (!types.isReifiable(((ArrayType)t).elemtype)) {
683 log.error(pos, "generic.array.creation");
684 t = types.createErrorType(t);
685 }
686 }
687 return t;
688 }
689
690 /** Check that type is a class or interface type.
691 * @param pos Position to be used for error reporting.
692 * @param t The type to be checked.
693 * @param noBounds True if type bounds are illegal here.
694 */
695 Type checkClassType(DiagnosticPosition pos, Type t, boolean noBounds) {
696 t = checkClassType(pos, t);
697 if (noBounds && t.isParameterized()) {
698 List<Type> args = t.getTypeArguments();
699 while (args.nonEmpty()) {
700 if (args.head.hasTag(WILDCARD))
701 return typeTagError(pos,
702 diags.fragment("type.req.exact"),
703 args.head);
704 args = args.tail;
705 }
706 }
707 return t;
708 }
709
710 /** Check that type is a reference type, i.e. a class, interface or array type
711 * or a type variable.
712 * @param pos Position to be used for error reporting.
713 * @param t The type to be checked.
714 */
715 Type checkRefType(DiagnosticPosition pos, Type t) {
716 if (t.isReference())
717 return t;
718 else
719 return typeTagError(pos,
720 diags.fragment("type.req.ref"),
721 t);
722 }
723
724 /** Check that each type is a reference type, i.e. a class, interface or array type
725 * or a type variable.
726 * @param trees Original trees, used for error reporting.
727 * @param types The types to be checked.
728 */
729 List<Type> checkRefTypes(List<JCExpression> trees, List<Type> types) {
730 List<JCExpression> tl = trees;
731 for (List<Type> l = types; l.nonEmpty(); l = l.tail) {
732 l.head = checkRefType(tl.head.pos(), l.head);
733 tl = tl.tail;
734 }
735 return types;
736 }
737
738 /** Check that type is a null or reference type.
739 * @param pos Position to be used for error reporting.
740 * @param t The type to be checked.
741 */
742 Type checkNullOrRefType(DiagnosticPosition pos, Type t) {
743 if (t.isReference() || t.hasTag(BOT))
744 return t;
745 else
746 return typeTagError(pos,
747 diags.fragment("type.req.ref"),
748 t);
749 }
750
751 /** Check that flag set does not contain elements of two conflicting sets. s
752 * Return true if it doesn't.
753 * @param pos Position to be used for error reporting.
754 * @param flags The set of flags to be checked.
755 * @param set1 Conflicting flags set #1.
756 * @param set2 Conflicting flags set #2.
757 */
758 boolean checkDisjoint(DiagnosticPosition pos, long flags, long set1, long set2) {
759 if ((flags & set1) != 0 && (flags & set2) != 0) {
760 log.error(pos,
761 "illegal.combination.of.modifiers",
762 asFlagSet(TreeInfo.firstFlag(flags & set1)),
763 asFlagSet(TreeInfo.firstFlag(flags & set2)));
764 return false;
765 } else
766 return true;
767 }
768
769 /** Check that usage of diamond operator is correct (i.e. diamond should not
770 * be used with non-generic classes or in anonymous class creation expressions)
771 */
772 Type checkDiamond(JCNewClass tree, Type t) {
773 if (!TreeInfo.isDiamond(tree) ||
774 t.isErroneous()) {
775 return checkClassType(tree.clazz.pos(), t, true);
776 } else if (tree.def != null) {
777 log.error(tree.clazz.pos(),
778 "cant.apply.diamond.1",
779 t, diags.fragment("diamond.and.anon.class", t));
780 return types.createErrorType(t);
781 } else if (t.tsym.type.getTypeArguments().isEmpty()) {
782 log.error(tree.clazz.pos(),
783 "cant.apply.diamond.1",
784 t, diags.fragment("diamond.non.generic", t));
785 return types.createErrorType(t);
786 } else if (tree.typeargs != null &&
787 tree.typeargs.nonEmpty()) {
788 log.error(tree.clazz.pos(),
789 "cant.apply.diamond.1",
790 t, diags.fragment("diamond.and.explicit.params", t));
791 return types.createErrorType(t);
792 } else {
793 return t;
794 }
795 }
796
797 void checkVarargsMethodDecl(Env<AttrContext> env, JCMethodDecl tree) {
798 MethodSymbol m = tree.sym;
799 if (!allowSimplifiedVarargs) return;
800 boolean hasTrustMeAnno = m.attribute(syms.trustMeType.tsym) != null;
801 Type varargElemType = null;
802 if (m.isVarArgs()) {
803 varargElemType = types.elemtype(tree.params.last().type);
804 }
805 if (hasTrustMeAnno && !isTrustMeAllowedOnMethod(m)) {
806 if (varargElemType != null) {
807 log.error(tree,
808 "varargs.invalid.trustme.anno",
809 syms.trustMeType.tsym,
810 allowPrivateSafeVarargs ?
811 diags.fragment("varargs.trustme.on.virtual.varargs", m) :
812 diags.fragment("varargs.trustme.on.virtual.varargs.final.only", m));
813 } else {
814 log.error(tree,
815 "varargs.invalid.trustme.anno",
816 syms.trustMeType.tsym,
817 diags.fragment("varargs.trustme.on.non.varargs.meth", m));
818 }
819 } else if (hasTrustMeAnno && varargElemType != null &&
820 types.isReifiable(varargElemType)) {
821 warnUnsafeVararg(tree,
822 "varargs.redundant.trustme.anno",
823 syms.trustMeType.tsym,
824 diags.fragment("varargs.trustme.on.reifiable.varargs", varargElemType));
825 }
826 else if (!hasTrustMeAnno && varargElemType != null &&
827 !types.isReifiable(varargElemType)) {
828 warnUnchecked(tree.params.head.pos(), "unchecked.varargs.non.reifiable.type", varargElemType);
829 }
830 }
831 //where
832 private boolean isTrustMeAllowedOnMethod(Symbol s) {
833 return (s.flags() & VARARGS) != 0 &&
834 (s.isConstructor() ||
835 (s.flags() & (STATIC | FINAL |
836 (allowPrivateSafeVarargs ? PRIVATE : 0) )) != 0);
837 }
838
839 Type checkMethod(final Type mtype,
840 final Symbol sym,
841 final Env<AttrContext> env,
842 final List<JCExpression> argtrees,
843 final List<Type> argtypes,
844 final boolean useVarargs,
845 InferenceContext inferenceContext) {
846 // System.out.println("call : " + env.tree);
847 // System.out.println("method : " + owntype);
848 // System.out.println("actuals: " + argtypes);
849 if (inferenceContext.free(mtype)) {
850 inferenceContext.addFreeTypeListener(List.of(mtype), new FreeTypeListener() {
851 public void typesInferred(InferenceContext inferenceContext) {
852 checkMethod(inferenceContext.asInstType(mtype), sym, env, argtrees, argtypes, useVarargs, inferenceContext);
853 }
854 });
855 return mtype;
856 }
857 Type owntype = mtype;
858 List<Type> formals = owntype.getParameterTypes();
859 List<Type> nonInferred = sym.type.getParameterTypes();
860 if (nonInferred.length() != formals.length()) nonInferred = formals;
861 Type last = useVarargs ? formals.last() : null;
862 if (sym.name == names.init && sym.owner == syms.enumSym) {
863 formals = formals.tail.tail;
864 nonInferred = nonInferred.tail.tail;
865 }
866 List<JCExpression> args = argtrees;
867 if (args != null) {
868 //this is null when type-checking a method reference
869 while (formals.head != last) {
870 JCTree arg = args.head;
871 Warner warn = convertWarner(arg.pos(), arg.type, nonInferred.head);
872 assertConvertible(arg, arg.type, formals.head, warn);
873 args = args.tail;
874 formals = formals.tail;
875 nonInferred = nonInferred.tail;
876 }
877 if (useVarargs) {
878 Type varArg = types.elemtype(last);
879 while (args.tail != null) {
880 JCTree arg = args.head;
881 Warner warn = convertWarner(arg.pos(), arg.type, varArg);
882 assertConvertible(arg, arg.type, varArg, warn);
883 args = args.tail;
884 }
885 } else if ((sym.flags() & (VARARGS | SIGNATURE_POLYMORPHIC)) == VARARGS) {
886 // non-varargs call to varargs method
887 Type varParam = owntype.getParameterTypes().last();
888 Type lastArg = argtypes.last();
889 if (types.isSubtypeUnchecked(lastArg, types.elemtype(varParam)) &&
890 !types.isSameType(types.erasure(varParam), types.erasure(lastArg)))
891 log.warning(argtrees.last().pos(), "inexact.non-varargs.call",
892 types.elemtype(varParam), varParam);
893 }
894 }
895 if (useVarargs) {
896 Type argtype = owntype.getParameterTypes().last();
897 if (!types.isReifiable(argtype) &&
898 (!allowSimplifiedVarargs ||
899 sym.baseSymbol().attribute(syms.trustMeType.tsym) == null ||
900 !isTrustMeAllowedOnMethod(sym))) {
901 warnUnchecked(env.tree.pos(),
902 "unchecked.generic.array.creation",
903 argtype);
904 }
905 if ((sym.baseSymbol().flags() & SIGNATURE_POLYMORPHIC) == 0) {
906 TreeInfo.setVarargsElement(env.tree, types.elemtype(argtype));
907 }
908 }
909 PolyKind pkind = (sym.type.hasTag(FORALL) &&
910 sym.type.getReturnType().containsAny(((ForAll)sym.type).tvars)) ?
911 PolyKind.POLY : PolyKind.STANDALONE;
912 TreeInfo.setPolyKind(env.tree, pkind);
913 return owntype;
914 }
915 //where
916 private void assertConvertible(JCTree tree, Type actual, Type formal, Warner warn) {
917 if (types.isConvertible(actual, formal, warn))
918 return;
919
920 if (formal.isCompound()
921 && types.isSubtype(actual, types.supertype(formal))
922 && types.isSubtypeUnchecked(actual, types.interfaces(formal), warn))
923 return;
924 }
925
926 /**
927 * Check that type 't' is a valid instantiation of a generic class
928 * (see JLS 4.5)
929 *
930 * @param t class type to be checked
931 * @return true if 't' is well-formed
932 */
933 public boolean checkValidGenericType(Type t) {
934 return firstIncompatibleTypeArg(t) == null;
935 }
936 //WHERE
937 private Type firstIncompatibleTypeArg(Type type) {
938 List<Type> formals = type.tsym.type.allparams();
939 List<Type> actuals = type.allparams();
940 List<Type> args = type.getTypeArguments();
941 List<Type> forms = type.tsym.type.getTypeArguments();
942 ListBuffer<Type> bounds_buf = new ListBuffer<>();
943
944 // For matching pairs of actual argument types `a' and
945 // formal type parameters with declared bound `b' ...
946 while (args.nonEmpty() && forms.nonEmpty()) {
947 // exact type arguments needs to know their
948 // bounds (for upper and lower bound
949 // calculations). So we create new bounds where
950 // type-parameters are replaced with actuals argument types.
951 bounds_buf.append(types.subst(forms.head.getUpperBound(), formals, actuals));
952 args = args.tail;
953 forms = forms.tail;
954 }
955
956 args = type.getTypeArguments();
957 List<Type> tvars_cap = types.substBounds(formals,
958 formals,
959 types.capture(type).allparams());
960 while (args.nonEmpty() && tvars_cap.nonEmpty()) {
961 // Let the actual arguments know their bound
962 args.head.withTypeVar((TypeVar)tvars_cap.head);
963 args = args.tail;
964 tvars_cap = tvars_cap.tail;
965 }
966
967 args = type.getTypeArguments();
968 List<Type> bounds = bounds_buf.toList();
969
970 while (args.nonEmpty() && bounds.nonEmpty()) {
971 Type actual = args.head;
972 if (!isTypeArgErroneous(actual) &&
973 !bounds.head.isErroneous() &&
974 !checkExtends(actual, bounds.head)) {
975 return args.head;
976 }
977 args = args.tail;
978 bounds = bounds.tail;
979 }
980
981 args = type.getTypeArguments();
982 bounds = bounds_buf.toList();
983
984 for (Type arg : types.capture(type).getTypeArguments()) {
985 if (arg.hasTag(TYPEVAR) &&
986 arg.getUpperBound().isErroneous() &&
987 !bounds.head.isErroneous() &&
988 !isTypeArgErroneous(args.head)) {
989 return args.head;
990 }
991 bounds = bounds.tail;
992 args = args.tail;
993 }
994
995 return null;
996 }
997 //where
998 boolean isTypeArgErroneous(Type t) {
999 return isTypeArgErroneous.visit(t);
1000 }
1001
1002 Types.UnaryVisitor<Boolean> isTypeArgErroneous = new Types.UnaryVisitor<Boolean>() {
1003 public Boolean visitType(Type t, Void s) {
1004 return t.isErroneous();
1005 }
1006 @Override
1007 public Boolean visitTypeVar(TypeVar t, Void s) {
1008 return visit(t.getUpperBound());
1009 }
1010 @Override
1011 public Boolean visitCapturedType(CapturedType t, Void s) {
1012 return visit(t.getUpperBound()) ||
1013 visit(t.getLowerBound());
1014 }
1015 @Override
1016 public Boolean visitWildcardType(WildcardType t, Void s) {
1017 return visit(t.type);
1018 }
1019 };
1020
1021 /** Check that given modifiers are legal for given symbol and
1022 * return modifiers together with any implicit modifiers for that symbol.
1023 * Warning: we can't use flags() here since this method
1024 * is called during class enter, when flags() would cause a premature
1025 * completion.
1026 * @param pos Position to be used for error reporting.
1027 * @param flags The set of modifiers given in a definition.
1028 * @param sym The defined symbol.
1029 */
1030 long checkFlags(DiagnosticPosition pos, long flags, Symbol sym, JCTree tree) {
1031 long mask;
1032 long implicit = 0;
1033
1034 switch (sym.kind) {
1035 case VAR:
1036 if (TreeInfo.isReceiverParam(tree))
1037 mask = ReceiverParamFlags;
1038 else if (sym.owner.kind != TYP)
1039 mask = LocalVarFlags;
1040 else if ((sym.owner.flags_field & INTERFACE) != 0)
1041 mask = implicit = InterfaceVarFlags;
1042 else
1043 mask = VarFlags;
1044 break;
1045 case MTH:
1046 if (sym.name == names.init) {
1047 if ((sym.owner.flags_field & ENUM) != 0) {
1048 // enum constructors cannot be declared public or
1049 // protected and must be implicitly or explicitly
1050 // private
1051 implicit = PRIVATE;
1052 mask = PRIVATE;
1053 } else
1054 mask = ConstructorFlags;
1055 } else if ((sym.owner.flags_field & INTERFACE) != 0) {
1056 if ((sym.owner.flags_field & ANNOTATION) != 0) {
1057 mask = AnnotationTypeElementMask;
1058 implicit = PUBLIC | ABSTRACT;
1059 } else if ((flags & (DEFAULT | STATIC)) != 0) {
1060 mask = InterfaceMethodMask;
1061 implicit = PUBLIC;
1062 if ((flags & DEFAULT) != 0) {
1063 implicit |= ABSTRACT;
1064 }
1065 } else {
1066 mask = implicit = InterfaceMethodFlags;
1067 }
1068 } else {
1069 mask = MethodFlags;
1070 }
1071 // Imply STRICTFP if owner has STRICTFP set.
1072 if (((flags|implicit) & Flags.ABSTRACT) == 0 ||
1073 ((flags) & Flags.DEFAULT) != 0)
1074 implicit |= sym.owner.flags_field & STRICTFP;
1075 break;
1076 case TYP:
1077 if (sym.isLocal()) {
1078 mask = LocalClassFlags;
1079 if (sym.name.isEmpty()) { // Anonymous class
1080 // JLS: Anonymous classes are final.
1081 implicit |= FINAL;
1082 }
1083 if ((sym.owner.flags_field & STATIC) == 0 &&
1084 (flags & ENUM) != 0)
1085 log.error(pos, "enums.must.be.static");
1086 } else if (sym.owner.kind == TYP) {
1087 mask = MemberClassFlags;
1088 if (sym.owner.owner.kind == PCK ||
1089 (sym.owner.flags_field & STATIC) != 0)
1090 mask |= STATIC;
1091 else if ((flags & ENUM) != 0)
1092 log.error(pos, "enums.must.be.static");
1093 // Nested interfaces and enums are always STATIC (Spec ???)
1094 if ((flags & (INTERFACE | ENUM)) != 0 ) implicit = STATIC;
1095 } else {
1096 mask = ClassFlags;
1097 }
1098 // Interfaces are always ABSTRACT
1099 if ((flags & INTERFACE) != 0) implicit |= ABSTRACT;
1100
1101 if ((flags & ENUM) != 0) {
1102 // enums can't be declared abstract or final
1103 mask &= ~(ABSTRACT | FINAL);
1104 implicit |= implicitEnumFinalFlag(tree);
1105 }
1106 // Imply STRICTFP if owner has STRICTFP set.
1107 implicit |= sym.owner.flags_field & STRICTFP;
1108 break;
1109 default:
1110 throw new AssertionError();
1111 }
1112 long illegal = flags & ExtendedStandardFlags & ~mask;
1113 if (illegal != 0) {
1114 if ((illegal & INTERFACE) != 0) {
1115 log.error(pos, "intf.not.allowed.here");
1116 mask |= INTERFACE;
1117 }
1118 else {
1119 log.error(pos,
1120 "mod.not.allowed.here", asFlagSet(illegal));
1121 }
1122 }
1123 else if ((sym.kind == TYP ||
1124 // ISSUE: Disallowing abstract&private is no longer appropriate
1125 // in the presence of inner classes. Should it be deleted here?
1126 checkDisjoint(pos, flags,
1127 ABSTRACT,
1128 PRIVATE | STATIC | DEFAULT))
1129 &&
1130 checkDisjoint(pos, flags,
1131 STATIC,
1132 DEFAULT)
1133 &&
1134 checkDisjoint(pos, flags,
1135 ABSTRACT | INTERFACE,
1136 FINAL | NATIVE | SYNCHRONIZED)
1137 &&
1138 checkDisjoint(pos, flags,
1139 PUBLIC,
1140 PRIVATE | PROTECTED)
1141 &&
1142 checkDisjoint(pos, flags,
1143 PRIVATE,
1144 PUBLIC | PROTECTED)
1145 &&
1146 checkDisjoint(pos, flags,
1147 FINAL,
1148 VOLATILE)
1149 &&
1150 (sym.kind == TYP ||
1151 checkDisjoint(pos, flags,
1152 ABSTRACT | NATIVE,
1153 STRICTFP))) {
1154 // skip
1155 }
1156 return flags & (mask | ~ExtendedStandardFlags) | implicit;
1157 }
1158
1159
1160 /** Determine if this enum should be implicitly final.
1161 *
1162 * If the enum has no specialized enum contants, it is final.
1163 *
1164 * If the enum does have specialized enum contants, it is
1165 * <i>not</i> final.
1166 */
1167 private long implicitEnumFinalFlag(JCTree tree) {
1168 if (!tree.hasTag(CLASSDEF)) return 0;
1169 class SpecialTreeVisitor extends JCTree.Visitor {
1170 boolean specialized;
1171 SpecialTreeVisitor() {
1172 this.specialized = false;
1173 }
1174
1175 @Override
1176 public void visitTree(JCTree tree) { /* no-op */ }
1177
1178 @Override
1179 public void visitVarDef(JCVariableDecl tree) {
1180 if ((tree.mods.flags & ENUM) != 0) {
1181 if (tree.init instanceof JCNewClass &&
1182 ((JCNewClass) tree.init).def != null) {
1183 specialized = true;
1184 }
1185 }
1186 }
1187 }
1188
1189 SpecialTreeVisitor sts = new SpecialTreeVisitor();
1190 JCClassDecl cdef = (JCClassDecl) tree;
1191 for (JCTree defs: cdef.defs) {
1192 defs.accept(sts);
1193 if (sts.specialized) return 0;
1194 }
1195 return FINAL;
1196 }
1197
1198 /* *************************************************************************
1199 * Type Validation
1200 **************************************************************************/
1201
1202 /** Validate a type expression. That is,
1203 * check that all type arguments of a parametric type are within
1204 * their bounds. This must be done in a second phase after type attribution
1205 * since a class might have a subclass as type parameter bound. E.g:
1206 *
1207 * <pre>{@code
1208 * class B<A extends C> { ... }
1209 * class C extends B<C> { ... }
1210 * }</pre>
1211 *
1212 * and we can't make sure that the bound is already attributed because
1213 * of possible cycles.
1214 *
1215 * Visitor method: Validate a type expression, if it is not null, catching
1216 * and reporting any completion failures.
1217 */
1218 void validate(JCTree tree, Env<AttrContext> env) {
1219 validate(tree, env, true);
1220 }
1221 void validate(JCTree tree, Env<AttrContext> env, boolean checkRaw) {
1222 new Validator(env).validateTree(tree, checkRaw, true);
1223 }
1224
1225 /** Visitor method: Validate a list of type expressions.
1226 */
1227 void validate(List<? extends JCTree> trees, Env<AttrContext> env) {
1228 for (List<? extends JCTree> l = trees; l.nonEmpty(); l = l.tail)
1229 validate(l.head, env);
1230 }
1231
1232 /** A visitor class for type validation.
1233 */
1234 class Validator extends JCTree.Visitor {
1235
1236 boolean checkRaw;
1237 boolean isOuter;
1238 Env<AttrContext> env;
1239
1240 Validator(Env<AttrContext> env) {
1241 this.env = env;
1242 }
1243
1244 @Override
1245 public void visitTypeArray(JCArrayTypeTree tree) {
1246 validateTree(tree.elemtype, checkRaw, isOuter);
1247 }
1248
1249 @Override
1250 public void visitTypeApply(JCTypeApply tree) {
1251 if (tree.type.hasTag(CLASS)) {
1252 List<JCExpression> args = tree.arguments;
1253 List<Type> forms = tree.type.tsym.type.getTypeArguments();
1254
1255 Type incompatibleArg = firstIncompatibleTypeArg(tree.type);
1256 if (incompatibleArg != null) {
1257 for (JCTree arg : tree.arguments) {
1258 if (arg.type == incompatibleArg) {
1259 log.error(arg, "not.within.bounds", incompatibleArg, forms.head);
1260 }
1261 forms = forms.tail;
1262 }
1263 }
1264
1265 forms = tree.type.tsym.type.getTypeArguments();
1266
1267 boolean is_java_lang_Class = tree.type.tsym.flatName() == names.java_lang_Class;
1268
1269 // For matching pairs of actual argument types `a' and
1270 // formal type parameters with declared bound `b' ...
1271 while (args.nonEmpty() && forms.nonEmpty()) {
1272 validateTree(args.head,
1273 !(isOuter && is_java_lang_Class),
1274 false);
1275 args = args.tail;
1276 forms = forms.tail;
1277 }
1278
1279 // Check that this type is either fully parameterized, or
1280 // not parameterized at all.
1281 if (tree.type.getEnclosingType().isRaw())
1282 log.error(tree.pos(), "improperly.formed.type.inner.raw.param");
1283 if (tree.clazz.hasTag(SELECT))
1284 visitSelectInternal((JCFieldAccess)tree.clazz);
1285 }
1286 }
1287
1288 @Override
1289 public void visitTypeParameter(JCTypeParameter tree) {
1290 validateTrees(tree.bounds, true, isOuter);
1291 checkClassBounds(tree.pos(), tree.type);
1292 }
1293
1294 @Override
1295 public void visitWildcard(JCWildcard tree) {
1296 if (tree.inner != null)
1297 validateTree(tree.inner, true, isOuter);
1298 }
1299
1300 @Override
1301 public void visitSelect(JCFieldAccess tree) {
1302 if (tree.type.hasTag(CLASS)) {
1303 visitSelectInternal(tree);
1304
1305 // Check that this type is either fully parameterized, or
1306 // not parameterized at all.
1307 if (tree.selected.type.isParameterized() && tree.type.tsym.type.getTypeArguments().nonEmpty())
1308 log.error(tree.pos(), "improperly.formed.type.param.missing");
1309 }
1310 }
1311
1312 public void visitSelectInternal(JCFieldAccess tree) {
1313 if (tree.type.tsym.isStatic() &&
1314 tree.selected.type.isParameterized()) {
1315 // The enclosing type is not a class, so we are
1316 // looking at a static member type. However, the
1317 // qualifying expression is parameterized.
1318 log.error(tree.pos(), "cant.select.static.class.from.param.type");
1319 } else {
1320 // otherwise validate the rest of the expression
1321 tree.selected.accept(this);
1322 }
1323 }
1324
1325 @Override
1326 public void visitAnnotatedType(JCAnnotatedType tree) {
1327 tree.underlyingType.accept(this);
1328 }
1329
1330 @Override
1331 public void visitTypeIdent(JCPrimitiveTypeTree that) {
1332 if (that.type.hasTag(TypeTag.VOID)) {
1333 log.error(that.pos(), "void.not.allowed.here");
1334 }
1335 super.visitTypeIdent(that);
1336 }
1337
1338 /** Default visitor method: do nothing.
1339 */
1340 @Override
1341 public void visitTree(JCTree tree) {
1342 }
1343
1344 public void validateTree(JCTree tree, boolean checkRaw, boolean isOuter) {
1345 if (tree != null) {
1346 boolean prevCheckRaw = this.checkRaw;
1347 this.checkRaw = checkRaw;
1348 this.isOuter = isOuter;
1349
1350 try {
1351 tree.accept(this);
1352 if (checkRaw)
1353 checkRaw(tree, env);
1354 } catch (CompletionFailure ex) {
1355 completionError(tree.pos(), ex);
1356 } finally {
1357 this.checkRaw = prevCheckRaw;
1358 }
1359 }
1360 }
1361
1362 public void validateTrees(List<? extends JCTree> trees, boolean checkRaw, boolean isOuter) {
1363 for (List<? extends JCTree> l = trees; l.nonEmpty(); l = l.tail)
1364 validateTree(l.head, checkRaw, isOuter);
1365 }
1366 }
1367
1368 void checkRaw(JCTree tree, Env<AttrContext> env) {
1369 if (lint.isEnabled(LintCategory.RAW) &&
1370 tree.type.hasTag(CLASS) &&
1371 !TreeInfo.isDiamond(tree) &&
1372 !withinAnonConstr(env) &&
1373 tree.type.isRaw()) {
1374 log.warning(LintCategory.RAW,
1375 tree.pos(), "raw.class.use", tree.type, tree.type.tsym.type);
1376 }
1377 }
1378 //where
1379 private boolean withinAnonConstr(Env<AttrContext> env) {
1380 return env.enclClass.name.isEmpty() &&
1381 env.enclMethod != null && env.enclMethod.name == names.init;
1382 }
1383
1384 /* *************************************************************************
1385 * Exception checking
1386 **************************************************************************/
1387
1388 /* The following methods treat classes as sets that contain
1389 * the class itself and all their subclasses
1390 */
1391
1392 /** Is given type a subtype of some of the types in given list?
1393 */
1394 boolean subset(Type t, List<Type> ts) {
1395 for (List<Type> l = ts; l.nonEmpty(); l = l.tail)
1396 if (types.isSubtype(t, l.head)) return true;
1397 return false;
1398 }
1399
1400 /** Is given type a subtype or supertype of
1401 * some of the types in given list?
1402 */
1403 boolean intersects(Type t, List<Type> ts) {
1404 for (List<Type> l = ts; l.nonEmpty(); l = l.tail)
1405 if (types.isSubtype(t, l.head) || types.isSubtype(l.head, t)) return true;
1406 return false;
1407 }
1408
1409 /** Add type set to given type list, unless it is a subclass of some class
1410 * in the list.
1411 */
1412 List<Type> incl(Type t, List<Type> ts) {
1413 return subset(t, ts) ? ts : excl(t, ts).prepend(t);
1414 }
1415
1416 /** Remove type set from type set list.
1417 */
1418 List<Type> excl(Type t, List<Type> ts) {
1419 if (ts.isEmpty()) {
1420 return ts;
1421 } else {
1422 List<Type> ts1 = excl(t, ts.tail);
1423 if (types.isSubtype(ts.head, t)) return ts1;
1424 else if (ts1 == ts.tail) return ts;
1425 else return ts1.prepend(ts.head);
1426 }
1427 }
1428
1429 /** Form the union of two type set lists.
1430 */
1431 List<Type> union(List<Type> ts1, List<Type> ts2) {
1432 List<Type> ts = ts1;
1433 for (List<Type> l = ts2; l.nonEmpty(); l = l.tail)
1434 ts = incl(l.head, ts);
1435 return ts;
1436 }
1437
1438 /** Form the difference of two type lists.
1439 */
1440 List<Type> diff(List<Type> ts1, List<Type> ts2) {
1441 List<Type> ts = ts1;
1442 for (List<Type> l = ts2; l.nonEmpty(); l = l.tail)
1443 ts = excl(l.head, ts);
1444 return ts;
1445 }
1446
1447 /** Form the intersection of two type lists.
1448 */
1449 public List<Type> intersect(List<Type> ts1, List<Type> ts2) {
1450 List<Type> ts = List.nil();
1451 for (List<Type> l = ts1; l.nonEmpty(); l = l.tail)
1452 if (subset(l.head, ts2)) ts = incl(l.head, ts);
1453 for (List<Type> l = ts2; l.nonEmpty(); l = l.tail)
1454 if (subset(l.head, ts1)) ts = incl(l.head, ts);
1455 return ts;
1456 }
1457
1458 /** Is exc an exception symbol that need not be declared?
1459 */
1460 boolean isUnchecked(ClassSymbol exc) {
1461 return
1462 exc.kind == ERR ||
1463 exc.isSubClass(syms.errorType.tsym, types) ||
1464 exc.isSubClass(syms.runtimeExceptionType.tsym, types);
1465 }
1466
1467 /** Is exc an exception type that need not be declared?
1468 */
1469 boolean isUnchecked(Type exc) {
1470 return
1471 (exc.hasTag(TYPEVAR)) ? isUnchecked(types.supertype(exc)) :
1472 (exc.hasTag(CLASS)) ? isUnchecked((ClassSymbol)exc.tsym) :
1473 exc.hasTag(BOT);
1474 }
1475
1476 /** Same, but handling completion failures.
1477 */
1478 boolean isUnchecked(DiagnosticPosition pos, Type exc) {
1479 try {
1480 return isUnchecked(exc);
1481 } catch (CompletionFailure ex) {
1482 completionError(pos, ex);
1483 return true;
1484 }
1485 }
1486
1487 /** Is exc handled by given exception list?
1488 */
1489 boolean isHandled(Type exc, List<Type> handled) {
1490 return isUnchecked(exc) || subset(exc, handled);
1491 }
1492
1493 /** Return all exceptions in thrown list that are not in handled list.
1494 * @param thrown The list of thrown exceptions.
1495 * @param handled The list of handled exceptions.
1496 */
1497 List<Type> unhandled(List<Type> thrown, List<Type> handled) {
1498 List<Type> unhandled = List.nil();
1499 for (List<Type> l = thrown; l.nonEmpty(); l = l.tail)
1500 if (!isHandled(l.head, handled)) unhandled = unhandled.prepend(l.head);
1501 return unhandled;
1502 }
1503
1504 /* *************************************************************************
1505 * Overriding/Implementation checking
1506 **************************************************************************/
1507
1508 /** The level of access protection given by a flag set,
1509 * where PRIVATE is highest and PUBLIC is lowest.
1510 */
1511 static int protection(long flags) {
1512 switch ((short)(flags & AccessFlags)) {
1513 case PRIVATE: return 3;
1514 case PROTECTED: return 1;
1515 default:
1516 case PUBLIC: return 0;
1517 case 0: return 2;
1518 }
1519 }
1520
1521 /** A customized "cannot override" error message.
1522 * @param m The overriding method.
1523 * @param other The overridden method.
1524 * @return An internationalized string.
1525 */
1526 Object cannotOverride(MethodSymbol m, MethodSymbol other) {
1527 String key;
1528 if ((other.owner.flags() & INTERFACE) == 0)
1529 key = "cant.override";
1530 else if ((m.owner.flags() & INTERFACE) == 0)
1531 key = "cant.implement";
1532 else
1533 key = "clashes.with";
1534 return diags.fragment(key, m, m.location(), other, other.location());
1535 }
1536
1537 /** A customized "override" warning message.
1538 * @param m The overriding method.
1539 * @param other The overridden method.
1540 * @return An internationalized string.
1541 */
1542 Object uncheckedOverrides(MethodSymbol m, MethodSymbol other) {
1543 String key;
1544 if ((other.owner.flags() & INTERFACE) == 0)
1545 key = "unchecked.override";
1546 else if ((m.owner.flags() & INTERFACE) == 0)
1547 key = "unchecked.implement";
1548 else
1549 key = "unchecked.clash.with";
1550 return diags.fragment(key, m, m.location(), other, other.location());
1551 }
1552
1553 /** A customized "override" warning message.
1554 * @param m The overriding method.
1555 * @param other The overridden method.
1556 * @return An internationalized string.
1557 */
1558 Object varargsOverrides(MethodSymbol m, MethodSymbol other) {
1559 String key;
1560 if ((other.owner.flags() & INTERFACE) == 0)
1561 key = "varargs.override";
1562 else if ((m.owner.flags() & INTERFACE) == 0)
1563 key = "varargs.implement";
1564 else
1565 key = "varargs.clash.with";
1566 return diags.fragment(key, m, m.location(), other, other.location());
1567 }
1568
1569 /** Check that this method conforms with overridden method 'other'.
1570 * where `origin' is the class where checking started.
1571 * Complications:
1572 * (1) Do not check overriding of synthetic methods
1573 * (reason: they might be final).
1574 * todo: check whether this is still necessary.
1575 * (2) Admit the case where an interface proxy throws fewer exceptions
1576 * than the method it implements. Augment the proxy methods with the
1577 * undeclared exceptions in this case.
1578 * (3) When generics are enabled, admit the case where an interface proxy
1579 * has a result type
1580 * extended by the result type of the method it implements.
1581 * Change the proxies result type to the smaller type in this case.
1582 *
1583 * @param tree The tree from which positions
1584 * are extracted for errors.
1585 * @param m The overriding method.
1586 * @param other The overridden method.
1587 * @param origin The class of which the overriding method
1588 * is a member.
1589 */
1590 void checkOverride(JCTree tree,
1591 MethodSymbol m,
1592 MethodSymbol other,
1593 ClassSymbol origin) {
1594 // Don't check overriding of synthetic methods or by bridge methods.
1595 if ((m.flags() & (SYNTHETIC|BRIDGE)) != 0 || (other.flags() & SYNTHETIC) != 0) {
1596 return;
1597 }
1598
1599 // Error if static method overrides instance method (JLS 8.4.6.2).
1600 if ((m.flags() & STATIC) != 0 &&
1601 (other.flags() & STATIC) == 0) {
1602 log.error(TreeInfo.diagnosticPositionFor(m, tree), "override.static",
1603 cannotOverride(m, other));
1604 m.flags_field |= BAD_OVERRIDE;
1605 return;
1606 }
1607
1608 // Error if instance method overrides static or final
1609 // method (JLS 8.4.6.1).
1610 if ((other.flags() & FINAL) != 0 ||
1611 (m.flags() & STATIC) == 0 &&
1612 (other.flags() & STATIC) != 0) {
1613 log.error(TreeInfo.diagnosticPositionFor(m, tree), "override.meth",
1614 cannotOverride(m, other),
1615 asFlagSet(other.flags() & (FINAL | STATIC)));
1616 m.flags_field |= BAD_OVERRIDE;
1617 return;
1618 }
1619
1620 if ((m.owner.flags() & ANNOTATION) != 0) {
1621 // handled in validateAnnotationMethod
1622 return;
1623 }
1624
1625 // Error if overriding method has weaker access (JLS 8.4.6.3).
1626 if ((origin.flags() & INTERFACE) == 0 &&
1627 protection(m.flags()) > protection(other.flags())) {
1628 log.error(TreeInfo.diagnosticPositionFor(m, tree), "override.weaker.access",
1629 cannotOverride(m, other),
1630 (other.flags() & AccessFlags) == 0 ?
1631 "package" :
1632 asFlagSet(other.flags() & AccessFlags));
1633 m.flags_field |= BAD_OVERRIDE;
1634 return;
1635 }
1636
1637 Type mt = types.memberType(origin.type, m);
1638 Type ot = types.memberType(origin.type, other);
1639 // Error if overriding result type is different
1640 // (or, in the case of generics mode, not a subtype) of
1641 // overridden result type. We have to rename any type parameters
1642 // before comparing types.
1643 List<Type> mtvars = mt.getTypeArguments();
1644 List<Type> otvars = ot.getTypeArguments();
1645 Type mtres = mt.getReturnType();
1646 Type otres = types.subst(ot.getReturnType(), otvars, mtvars);
1647
1648 overrideWarner.clear();
1649 boolean resultTypesOK =
1650 types.returnTypeSubstitutable(mt, ot, otres, overrideWarner);
1651 if (!resultTypesOK) {
1652 log.error(TreeInfo.diagnosticPositionFor(m, tree),
1653 "override.incompatible.ret",
1654 cannotOverride(m, other),
1655 mtres, otres);
1656 m.flags_field |= BAD_OVERRIDE;
1657 return;
1658 } else if (overrideWarner.hasNonSilentLint(LintCategory.UNCHECKED)) {
1659 warnUnchecked(TreeInfo.diagnosticPositionFor(m, tree),
1660 "override.unchecked.ret",
1661 uncheckedOverrides(m, other),
1662 mtres, otres);
1663 }
1664
1665 // Error if overriding method throws an exception not reported
1666 // by overridden method.
1667 List<Type> otthrown = types.subst(ot.getThrownTypes(), otvars, mtvars);
1668 List<Type> unhandledErased = unhandled(mt.getThrownTypes(), types.erasure(otthrown));
1669 List<Type> unhandledUnerased = unhandled(mt.getThrownTypes(), otthrown);
1670 if (unhandledErased.nonEmpty()) {
1671 log.error(TreeInfo.diagnosticPositionFor(m, tree),
1672 "override.meth.doesnt.throw",
1673 cannotOverride(m, other),
1674 unhandledUnerased.head);
1675 m.flags_field |= BAD_OVERRIDE;
1676 return;
1677 }
1678 else if (unhandledUnerased.nonEmpty()) {
1679 warnUnchecked(TreeInfo.diagnosticPositionFor(m, tree),
1680 "override.unchecked.thrown",
1681 cannotOverride(m, other),
1682 unhandledUnerased.head);
1683 return;
1684 }
1685
1686 // Optional warning if varargs don't agree
1687 if ((((m.flags() ^ other.flags()) & Flags.VARARGS) != 0)
1688 && lint.isEnabled(LintCategory.OVERRIDES)) {
1689 log.warning(TreeInfo.diagnosticPositionFor(m, tree),
1690 ((m.flags() & Flags.VARARGS) != 0)
1691 ? "override.varargs.missing"
1692 : "override.varargs.extra",
1693 varargsOverrides(m, other));
1694 }
1695
1696 // Warn if instance method overrides bridge method (compiler spec ??)
1697 if ((other.flags() & BRIDGE) != 0) {
1698 log.warning(TreeInfo.diagnosticPositionFor(m, tree), "override.bridge",
1699 uncheckedOverrides(m, other));
1700 }
1701
1702 // Warn if a deprecated method overridden by a non-deprecated one.
1703 if (!isDeprecatedOverrideIgnorable(other, origin)) {
1704 Lint prevLint = setLint(lint.augment(m));
1705 try {
1706 checkDeprecated(TreeInfo.diagnosticPositionFor(m, tree), m, other);
1707 } finally {
1708 setLint(prevLint);
1709 }
1710 }
1711 }
1712 // where
1713 private boolean isDeprecatedOverrideIgnorable(MethodSymbol m, ClassSymbol origin) {
1714 // If the method, m, is defined in an interface, then ignore the issue if the method
1715 // is only inherited via a supertype and also implemented in the supertype,
1716 // because in that case, we will rediscover the issue when examining the method
1717 // in the supertype.
1718 // If the method, m, is not defined in an interface, then the only time we need to
1719 // address the issue is when the method is the supertype implemementation: any other
1720 // case, we will have dealt with when examining the supertype classes
1721 ClassSymbol mc = m.enclClass();
1722 Type st = types.supertype(origin.type);
1723 if (!st.hasTag(CLASS))
1724 return true;
1725 MethodSymbol stimpl = m.implementation((ClassSymbol)st.tsym, types, false);
1726
1727 if (mc != null && ((mc.flags() & INTERFACE) != 0)) {
1728 List<Type> intfs = types.interfaces(origin.type);
1729 return (intfs.contains(mc.type) ? false : (stimpl != null));
1730 }
1731 else
1732 return (stimpl != m);
1733 }
1734
1735
1736 // used to check if there were any unchecked conversions
1737 Warner overrideWarner = new Warner();
1738
1739 /** Check that a class does not inherit two concrete methods
1740 * with the same signature.
1741 * @param pos Position to be used for error reporting.
1742 * @param site The class type to be checked.
1743 */
1744 public void checkCompatibleConcretes(DiagnosticPosition pos, Type site) {
1745 Type sup = types.supertype(site);
1746 if (!sup.hasTag(CLASS)) return;
1747
1748 for (Type t1 = sup;
1749 t1.hasTag(CLASS) && t1.tsym.type.isParameterized();
1750 t1 = types.supertype(t1)) {
1751 for (Symbol s1 : t1.tsym.members().getSymbols(NON_RECURSIVE)) {
1752 if (s1.kind != MTH ||
1753 (s1.flags() & (STATIC|SYNTHETIC|BRIDGE)) != 0 ||
1754 !s1.isInheritedIn(site.tsym, types) ||
1755 ((MethodSymbol)s1).implementation(site.tsym,
1756 types,
1757 true) != s1)
1758 continue;
1759 Type st1 = types.memberType(t1, s1);
1760 int s1ArgsLength = st1.getParameterTypes().length();
1761 if (st1 == s1.type) continue;
1762
1763 for (Type t2 = sup;
1764 t2.hasTag(CLASS);
1765 t2 = types.supertype(t2)) {
1766 for (Symbol s2 : t2.tsym.members().getSymbolsByName(s1.name)) {
1767 if (s2 == s1 ||
1768 s2.kind != MTH ||
1769 (s2.flags() & (STATIC|SYNTHETIC|BRIDGE)) != 0 ||
1770 s2.type.getParameterTypes().length() != s1ArgsLength ||
1771 !s2.isInheritedIn(site.tsym, types) ||
1772 ((MethodSymbol)s2).implementation(site.tsym,
1773 types,
1774 true) != s2)
1775 continue;
1776 Type st2 = types.memberType(t2, s2);
1777 if (types.overrideEquivalent(st1, st2))
1778 log.error(pos, "concrete.inheritance.conflict",
1779 s1, t1, s2, t2, sup);
1780 }
1781 }
1782 }
1783 }
1784 }
1785
1786 /** Check that classes (or interfaces) do not each define an abstract
1787 * method with same name and arguments but incompatible return types.
1788 * @param pos Position to be used for error reporting.
1789 * @param t1 The first argument type.
1790 * @param t2 The second argument type.
1791 */
1792 public boolean checkCompatibleAbstracts(DiagnosticPosition pos,
1793 Type t1,
1794 Type t2,
1795 Type site) {
1796 if ((site.tsym.flags() & COMPOUND) != 0) {
1797 // special case for intersections: need to eliminate wildcards in supertypes
1798 t1 = types.capture(t1);
1799 t2 = types.capture(t2);
1800 }
1801 return firstIncompatibility(pos, t1, t2, site) == null;
1802 }
1803
1804 /** Return the first method which is defined with same args
1805 * but different return types in two given interfaces, or null if none
1806 * exists.
1807 * @param t1 The first type.
1808 * @param t2 The second type.
1809 * @param site The most derived type.
1810 * @returns symbol from t2 that conflicts with one in t1.
1811 */
1812 private Symbol firstIncompatibility(DiagnosticPosition pos, Type t1, Type t2, Type site) {
1813 Map<TypeSymbol,Type> interfaces1 = new HashMap<>();
1814 closure(t1, interfaces1);
1815 Map<TypeSymbol,Type> interfaces2;
1816 if (t1 == t2)
1817 interfaces2 = interfaces1;
1818 else
1819 closure(t2, interfaces1, interfaces2 = new HashMap<>());
1820
1821 for (Type t3 : interfaces1.values()) {
1822 for (Type t4 : interfaces2.values()) {
1823 Symbol s = firstDirectIncompatibility(pos, t3, t4, site);
1824 if (s != null) return s;
1825 }
1826 }
1827 return null;
1828 }
1829
1830 /** Compute all the supertypes of t, indexed by type symbol. */
1831 private void closure(Type t, Map<TypeSymbol,Type> typeMap) {
1832 if (!t.hasTag(CLASS)) return;
1833 if (typeMap.put(t.tsym, t) == null) {
1834 closure(types.supertype(t), typeMap);
1835 for (Type i : types.interfaces(t))
1836 closure(i, typeMap);
1837 }
1838 }
1839
1840 /** Compute all the supertypes of t, indexed by type symbol (except thise in typesSkip). */
1841 private void closure(Type t, Map<TypeSymbol,Type> typesSkip, Map<TypeSymbol,Type> typeMap) {
1842 if (!t.hasTag(CLASS)) return;
1843 if (typesSkip.get(t.tsym) != null) return;
1844 if (typeMap.put(t.tsym, t) == null) {
1845 closure(types.supertype(t), typesSkip, typeMap);
1846 for (Type i : types.interfaces(t))
1847 closure(i, typesSkip, typeMap);
1848 }
1849 }
1850
1851 /** Return the first method in t2 that conflicts with a method from t1. */
1852 private Symbol firstDirectIncompatibility(DiagnosticPosition pos, Type t1, Type t2, Type site) {
1853 for (Symbol s1 : t1.tsym.members().getSymbols(NON_RECURSIVE)) {
1854 Type st1 = null;
1855 if (s1.kind != MTH || !s1.isInheritedIn(site.tsym, types) ||
1856 (s1.flags() & SYNTHETIC) != 0) continue;
1857 Symbol impl = ((MethodSymbol)s1).implementation(site.tsym, types, false);
1858 if (impl != null && (impl.flags() & ABSTRACT) == 0) continue;
1859 for (Symbol s2 : t2.tsym.members().getSymbolsByName(s1.name)) {
1860 if (s1 == s2) continue;
1861 if (s2.kind != MTH || !s2.isInheritedIn(site.tsym, types) ||
1862 (s2.flags() & SYNTHETIC) != 0) continue;
1863 if (st1 == null) st1 = types.memberType(t1, s1);
1864 Type st2 = types.memberType(t2, s2);
1865 if (types.overrideEquivalent(st1, st2)) {
1866 List<Type> tvars1 = st1.getTypeArguments();
1867 List<Type> tvars2 = st2.getTypeArguments();
1868 Type rt1 = st1.getReturnType();
1869 Type rt2 = types.subst(st2.getReturnType(), tvars2, tvars1);
1870 boolean compat =
1871 types.isSameType(rt1, rt2) ||
1872 !rt1.isPrimitiveOrVoid() &&
1873 !rt2.isPrimitiveOrVoid() &&
1874 (types.covariantReturnType(rt1, rt2, types.noWarnings) ||
1875 types.covariantReturnType(rt2, rt1, types.noWarnings)) ||
1876 checkCommonOverriderIn(s1,s2,site);
1877 if (!compat) {
1878 log.error(pos, "types.incompatible.diff.ret",
1879 t1, t2, s2.name +
1880 "(" + types.memberType(t2, s2).getParameterTypes() + ")");
1881 return s2;
1882 }
1883 } else if (checkNameClash((ClassSymbol)site.tsym, s1, s2) &&
1884 !checkCommonOverriderIn(s1, s2, site)) {
1885 log.error(pos,
1886 "name.clash.same.erasure.no.override",
1887 s1, s1.location(),
1888 s2, s2.location());
1889 return s2;
1890 }
1891 }
1892 }
1893 return null;
1894 }
1895 //WHERE
1896 boolean checkCommonOverriderIn(Symbol s1, Symbol s2, Type site) {
1897 Map<TypeSymbol,Type> supertypes = new HashMap<>();
1898 Type st1 = types.memberType(site, s1);
1899 Type st2 = types.memberType(site, s2);
1900 closure(site, supertypes);
1901 for (Type t : supertypes.values()) {
1902 for (Symbol s3 : t.tsym.members().getSymbolsByName(s1.name)) {
1903 if (s3 == s1 || s3 == s2 || s3.kind != MTH || (s3.flags() & (BRIDGE|SYNTHETIC)) != 0) continue;
1904 Type st3 = types.memberType(site,s3);
1905 if (types.overrideEquivalent(st3, st1) &&
1906 types.overrideEquivalent(st3, st2) &&
1907 types.returnTypeSubstitutable(st3, st1) &&
1908 types.returnTypeSubstitutable(st3, st2)) {
1909 return true;
1910 }
1911 }
1912 }
1913 return false;
1914 }
1915
1916 /** Check that a given method conforms with any method it overrides.
1917 * @param tree The tree from which positions are extracted
1918 * for errors.
1919 * @param m The overriding method.
1920 */
1921 void checkOverride(JCMethodDecl tree, MethodSymbol m) {
1922 ClassSymbol origin = (ClassSymbol)m.owner;
1923 if ((origin.flags() & ENUM) != 0 && names.finalize.equals(m.name))
1924 if (m.overrides(syms.enumFinalFinalize, origin, types, false)) {
1925 log.error(tree.pos(), "enum.no.finalize");
1926 return;
1927 }
1928 for (Type t = origin.type; t.hasTag(CLASS);
1929 t = types.supertype(t)) {
1930 if (t != origin.type) {
1931 checkOverride(tree, t, origin, m);
1932 }
1933 for (Type t2 : types.interfaces(t)) {
1934 checkOverride(tree, t2, origin, m);
1935 }
1936 }
1937
1938 if (m.attribute(syms.overrideType.tsym) != null && !isOverrider(m)) {
1939 DiagnosticPosition pos = tree.pos();
1940 for (JCAnnotation a : tree.getModifiers().annotations) {
1941 if (a.annotationType.type.tsym == syms.overrideType.tsym) {
1942 pos = a.pos();
1943 break;
1944 }
1945 }
1946 log.error(pos, "method.does.not.override.superclass");
1947 }
1948 }
1949
1950 void checkOverride(JCTree tree, Type site, ClassSymbol origin, MethodSymbol m) {
1951 TypeSymbol c = site.tsym;
1952 for (Symbol sym : c.members().getSymbolsByName(m.name)) {
1953 if (m.overrides(sym, origin, types, false)) {
1954 if ((sym.flags() & ABSTRACT) == 0) {
1955 checkOverride(tree, m, (MethodSymbol)sym, origin);
1956 }
1957 }
1958 }
1959 }
1960
1961 private Filter<Symbol> equalsHasCodeFilter = new Filter<Symbol>() {
1962 public boolean accepts(Symbol s) {
1963 return MethodSymbol.implementation_filter.accepts(s) &&
1964 (s.flags() & BAD_OVERRIDE) == 0;
1965
1966 }
1967 };
1968
1969 public void checkClassOverrideEqualsAndHashIfNeeded(DiagnosticPosition pos,
1970 ClassSymbol someClass) {
1971 /* At present, annotations cannot possibly have a method that is override
1972 * equivalent with Object.equals(Object) but in any case the condition is
1973 * fine for completeness.
1974 */
1975 if (someClass == (ClassSymbol)syms.objectType.tsym ||
1976 someClass.isInterface() || someClass.isEnum() ||
1977 (someClass.flags() & ANNOTATION) != 0 ||
1978 (someClass.flags() & ABSTRACT) != 0) return;
1979 //anonymous inner classes implementing interfaces need especial treatment
1980 if (someClass.isAnonymous()) {
1981 List<Type> interfaces = types.interfaces(someClass.type);
1982 if (interfaces != null && !interfaces.isEmpty() &&
1983 interfaces.head.tsym == syms.comparatorType.tsym) return;
1984 }
1985 checkClassOverrideEqualsAndHash(pos, someClass);
1986 }
1987
1988 private void checkClassOverrideEqualsAndHash(DiagnosticPosition pos,
1989 ClassSymbol someClass) {
1990 if (lint.isEnabled(LintCategory.OVERRIDES)) {
1991 MethodSymbol equalsAtObject = (MethodSymbol)syms.objectType
1992 .tsym.members().findFirst(names.equals);
1993 MethodSymbol hashCodeAtObject = (MethodSymbol)syms.objectType
1994 .tsym.members().findFirst(names.hashCode);
1995 boolean overridesEquals = types.implementation(equalsAtObject,
1996 someClass, false, equalsHasCodeFilter).owner == someClass;
1997 boolean overridesHashCode = types.implementation(hashCodeAtObject,
1998 someClass, false, equalsHasCodeFilter) != hashCodeAtObject;
1999
2000 if (overridesEquals && !overridesHashCode) {
2001 log.warning(LintCategory.OVERRIDES, pos,
2002 "override.equals.but.not.hashcode", someClass);
2003 }
2004 }
2005 }
2006
2007 private boolean checkNameClash(ClassSymbol origin, Symbol s1, Symbol s2) {
2008 ClashFilter cf = new ClashFilter(origin.type);
2009 return (cf.accepts(s1) &&
2010 cf.accepts(s2) &&
2011 types.hasSameArgs(s1.erasure(types), s2.erasure(types)));
2012 }
2013
2014
2015 /** Check that all abstract members of given class have definitions.
2016 * @param pos Position to be used for error reporting.
2017 * @param c The class.
2018 */
2019 void checkAllDefined(DiagnosticPosition pos, ClassSymbol c) {
2020 MethodSymbol undef = types.firstUnimplementedAbstract(c);
2021 if (undef != null) {
2022 MethodSymbol undef1 =
2023 new MethodSymbol(undef.flags(), undef.name,
2024 types.memberType(c.type, undef), undef.owner);
2025 log.error(pos, "does.not.override.abstract",
2026 c, undef1, undef1.location());
2027 }
2028 }
2029
2030 void checkNonCyclicDecl(JCClassDecl tree) {
2031 CycleChecker cc = new CycleChecker();
2032 cc.scan(tree);
2033 if (!cc.errorFound && !cc.partialCheck) {
2034 tree.sym.flags_field |= ACYCLIC;
2035 }
2036 }
2037
2038 class CycleChecker extends TreeScanner {
2039
2040 List<Symbol> seenClasses = List.nil();
2041 boolean errorFound = false;
2042 boolean partialCheck = false;
2043
2044 private void checkSymbol(DiagnosticPosition pos, Symbol sym) {
2045 if (sym != null && sym.kind == TYP) {
2046 Env<AttrContext> classEnv = enter.getEnv((TypeSymbol)sym);
2047 if (classEnv != null) {
2048 DiagnosticSource prevSource = log.currentSource();
2049 try {
2050 log.useSource(classEnv.toplevel.sourcefile);
2051 scan(classEnv.tree);
2052 }
2053 finally {
2054 log.useSource(prevSource.getFile());
2055 }
2056 } else if (sym.kind == TYP) {
2057 checkClass(pos, sym, List.<JCTree>nil());
2058 }
2059 } else {
2060 //not completed yet
2061 partialCheck = true;
2062 }
2063 }
2064
2065 @Override
2066 public void visitSelect(JCFieldAccess tree) {
2067 super.visitSelect(tree);
2068 checkSymbol(tree.pos(), tree.sym);
2069 }
2070
2071 @Override
2072 public void visitIdent(JCIdent tree) {
2073 checkSymbol(tree.pos(), tree.sym);
2074 }
2075
2076 @Override
2077 public void visitTypeApply(JCTypeApply tree) {
2078 scan(tree.clazz);
2079 }
2080
2081 @Override
2082 public void visitTypeArray(JCArrayTypeTree tree) {
2083 scan(tree.elemtype);
2084 }
2085
2086 @Override
2087 public void visitClassDef(JCClassDecl tree) {
2088 List<JCTree> supertypes = List.nil();
2089 if (tree.getExtendsClause() != null) {
2090 supertypes = supertypes.prepend(tree.getExtendsClause());
2091 }
2092 if (tree.getImplementsClause() != null) {
2093 for (JCTree intf : tree.getImplementsClause()) {
2094 supertypes = supertypes.prepend(intf);
2095 }
2096 }
2097 checkClass(tree.pos(), tree.sym, supertypes);
2098 }
2099
2100 void checkClass(DiagnosticPosition pos, Symbol c, List<JCTree> supertypes) {
2101 if ((c.flags_field & ACYCLIC) != 0)
2102 return;
2103 if (seenClasses.contains(c)) {
2104 errorFound = true;
2105 noteCyclic(pos, (ClassSymbol)c);
2106 } else if (!c.type.isErroneous()) {
2107 try {
2108 seenClasses = seenClasses.prepend(c);
2109 if (c.type.hasTag(CLASS)) {
2110 if (supertypes.nonEmpty()) {
2111 scan(supertypes);
2112 }
2113 else {
2114 ClassType ct = (ClassType)c.type;
2115 if (ct.supertype_field == null ||
2116 ct.interfaces_field == null) {
2117 //not completed yet
2118 partialCheck = true;
2119 return;
2120 }
2121 checkSymbol(pos, ct.supertype_field.tsym);
2122 for (Type intf : ct.interfaces_field) {
2123 checkSymbol(pos, intf.tsym);
2124 }
2125 }
2126 if (c.owner.kind == TYP) {
2127 checkSymbol(pos, c.owner);
2128 }
2129 }
2130 } finally {
2131 seenClasses = seenClasses.tail;
2132 }
2133 }
2134 }
2135 }
2136
2137 /** Check for cyclic references. Issue an error if the
2138 * symbol of the type referred to has a LOCKED flag set.
2139 *
2140 * @param pos Position to be used for error reporting.
2141 * @param t The type referred to.
2142 */
2143 void checkNonCyclic(DiagnosticPosition pos, Type t) {
2144 checkNonCyclicInternal(pos, t);
2145 }
2146
2147
2148 void checkNonCyclic(DiagnosticPosition pos, TypeVar t) {
2149 checkNonCyclic1(pos, t, List.<TypeVar>nil());
2150 }
2151
2152 private void checkNonCyclic1(DiagnosticPosition pos, Type t, List<TypeVar> seen) {
2153 final TypeVar tv;
2154 if (t.hasTag(TYPEVAR) && (t.tsym.flags() & UNATTRIBUTED) != 0)
2155 return;
2156 if (seen.contains(t)) {
2157 tv = (TypeVar)t;
2158 tv.bound = types.createErrorType(t);
2159 log.error(pos, "cyclic.inheritance", t);
2160 } else if (t.hasTag(TYPEVAR)) {
2161 tv = (TypeVar)t;
2162 seen = seen.prepend(tv);
2163 for (Type b : types.getBounds(tv))
2164 checkNonCyclic1(pos, b, seen);
2165 }
2166 }
2167
2168 /** Check for cyclic references. Issue an error if the
2169 * symbol of the type referred to has a LOCKED flag set.
2170 *
2171 * @param pos Position to be used for error reporting.
2172 * @param t The type referred to.
2173 * @returns True if the check completed on all attributed classes
2174 */
2175 private boolean checkNonCyclicInternal(DiagnosticPosition pos, Type t) {
2176 boolean complete = true; // was the check complete?
2177 //- System.err.println("checkNonCyclicInternal("+t+");");//DEBUG
2178 Symbol c = t.tsym;
2179 if ((c.flags_field & ACYCLIC) != 0) return true;
2180
2181 if ((c.flags_field & LOCKED) != 0) {
2182 noteCyclic(pos, (ClassSymbol)c);
2183 } else if (!c.type.isErroneous()) {
2184 try {
2185 c.flags_field |= LOCKED;
2186 if (c.type.hasTag(CLASS)) {
2187 ClassType clazz = (ClassType)c.type;
2188 if (clazz.interfaces_field != null)
2189 for (List<Type> l=clazz.interfaces_field; l.nonEmpty(); l=l.tail)
2190 complete &= checkNonCyclicInternal(pos, l.head);
2191 if (clazz.supertype_field != null) {
2192 Type st = clazz.supertype_field;
2193 if (st != null && st.hasTag(CLASS))
2194 complete &= checkNonCyclicInternal(pos, st);
2195 }
2196 if (c.owner.kind == TYP)
2197 complete &= checkNonCyclicInternal(pos, c.owner.type);
2198 }
2199 } finally {
2200 c.flags_field &= ~LOCKED;
2201 }
2202 }
2203 if (complete)
2204 complete = ((c.flags_field & UNATTRIBUTED) == 0) && c.completer == null;
2205 if (complete) c.flags_field |= ACYCLIC;
2206 return complete;
2207 }
2208
2209 /** Note that we found an inheritance cycle. */
2210 private void noteCyclic(DiagnosticPosition pos, ClassSymbol c) {
2211 log.error(pos, "cyclic.inheritance", c);
2212 for (List<Type> l=types.interfaces(c.type); l.nonEmpty(); l=l.tail)
2213 l.head = types.createErrorType((ClassSymbol)l.head.tsym, Type.noType);
2214 Type st = types.supertype(c.type);
2215 if (st.hasTag(CLASS))
2216 ((ClassType)c.type).supertype_field = types.createErrorType((ClassSymbol)st.tsym, Type.noType);
2217 c.type = types.createErrorType(c, c.type);
2218 c.flags_field |= ACYCLIC;
2219 }
2220
2221 /** Check that all methods which implement some
2222 * method conform to the method they implement.
2223 * @param tree The class definition whose members are checked.
2224 */
2225 void checkImplementations(JCClassDecl tree) {
2226 checkImplementations(tree, tree.sym, tree.sym);
2227 }
2228 //where
2229 /** Check that all methods which implement some
2230 * method in `ic' conform to the method they implement.
2231 */
2232 void checkImplementations(JCTree tree, ClassSymbol origin, ClassSymbol ic) {
2233 for (List<Type> l = types.closure(ic.type); l.nonEmpty(); l = l.tail) {
2234 ClassSymbol lc = (ClassSymbol)l.head.tsym;
2235 if ((lc.flags() & ABSTRACT) != 0) {
2236 for (Symbol sym : lc.members().getSymbols(NON_RECURSIVE)) {
2237 if (sym.kind == MTH &&
2238 (sym.flags() & (STATIC|ABSTRACT)) == ABSTRACT) {
2239 MethodSymbol absmeth = (MethodSymbol)sym;
2240 MethodSymbol implmeth = absmeth.implementation(origin, types, false);
2241 if (implmeth != null && implmeth != absmeth &&
2242 (implmeth.owner.flags() & INTERFACE) ==
2243 (origin.flags() & INTERFACE)) {
2244 // don't check if implmeth is in a class, yet
2245 // origin is an interface. This case arises only
2246 // if implmeth is declared in Object. The reason is
2247 // that interfaces really don't inherit from
2248 // Object it's just that the compiler represents
2249 // things that way.
2250 checkOverride(tree, implmeth, absmeth, origin);
2251 }
2252 }
2253 }
2254 }
2255 }
2256 }
2257
2258 /** Check that all abstract methods implemented by a class are
2259 * mutually compatible.
2260 * @param pos Position to be used for error reporting.
2261 * @param c The class whose interfaces are checked.
2262 */
2263 void checkCompatibleSupertypes(DiagnosticPosition pos, Type c) {
2264 List<Type> supertypes = types.interfaces(c);
2265 Type supertype = types.supertype(c);
2266 if (supertype.hasTag(CLASS) &&
2267 (supertype.tsym.flags() & ABSTRACT) != 0)
2268 supertypes = supertypes.prepend(supertype);
2269 for (List<Type> l = supertypes; l.nonEmpty(); l = l.tail) {
2270 if (!l.head.getTypeArguments().isEmpty() &&
2271 !checkCompatibleAbstracts(pos, l.head, l.head, c))
2272 return;
2273 for (List<Type> m = supertypes; m != l; m = m.tail)
2274 if (!checkCompatibleAbstracts(pos, l.head, m.head, c))
2275 return;
2276 }
2277 checkCompatibleConcretes(pos, c);
2278 }
2279
2280 void checkConflicts(DiagnosticPosition pos, Symbol sym, TypeSymbol c) {
2281 for (Type ct = c.type; ct != Type.noType ; ct = types.supertype(ct)) {
2282 for (Symbol sym2 : ct.tsym.members().getSymbolsByName(sym.name, NON_RECURSIVE)) {
2283 // VM allows methods and variables with differing types
2284 if (sym.kind == sym2.kind &&
2285 types.isSameType(types.erasure(sym.type), types.erasure(sym2.type)) &&
2286 sym != sym2 &&
2287 (sym.flags() & Flags.SYNTHETIC) != (sym2.flags() & Flags.SYNTHETIC) &&
2288 (sym.flags() & IPROXY) == 0 && (sym2.flags() & IPROXY) == 0 &&
2289 (sym.flags() & BRIDGE) == 0 && (sym2.flags() & BRIDGE) == 0) {
2290 syntheticError(pos, (sym2.flags() & SYNTHETIC) == 0 ? sym2 : sym);
2291 return;
2292 }
2293 }
2294 }
2295 }
2296
2297 /** Check that all non-override equivalent methods accessible from 'site'
2298 * are mutually compatible (JLS 8.4.8/9.4.1).
2299 *
2300 * @param pos Position to be used for error reporting.
2301 * @param site The class whose methods are checked.
2302 * @param sym The method symbol to be checked.
2303 */
2304 void checkOverrideClashes(DiagnosticPosition pos, Type site, MethodSymbol sym) {
2305 ClashFilter cf = new ClashFilter(site);
2306 //for each method m1 that is overridden (directly or indirectly)
2307 //by method 'sym' in 'site'...
2308
2309 List<MethodSymbol> potentiallyAmbiguousList = List.nil();
2310 boolean overridesAny = false;
2311 for (Symbol m1 : types.membersClosure(site, false).getSymbolsByName(sym.name, cf)) {
2312 if (!sym.overrides(m1, site.tsym, types, false)) {
2313 if (m1 == sym) {
2314 continue;
2315 }
2316
2317 if (!overridesAny) {
2318 potentiallyAmbiguousList = potentiallyAmbiguousList.prepend((MethodSymbol)m1);
2319 }
2320 continue;
2321 }
2322
2323 if (m1 != sym) {
2324 overridesAny = true;
2325 potentiallyAmbiguousList = List.nil();
2326 }
2327
2328 //...check each method m2 that is a member of 'site'
2329 for (Symbol m2 : types.membersClosure(site, false).getSymbolsByName(sym.name, cf)) {
2330 if (m2 == m1) continue;
2331 //if (i) the signature of 'sym' is not a subsignature of m1 (seen as
2332 //a member of 'site') and (ii) m1 has the same erasure as m2, issue an error
2333 if (!types.isSubSignature(sym.type, types.memberType(site, m2), allowStrictMethodClashCheck) &&
2334 types.hasSameArgs(m2.erasure(types), m1.erasure(types))) {
2335 sym.flags_field |= CLASH;
2336 String key = m1 == sym ?
2337 "name.clash.same.erasure.no.override" :
2338 "name.clash.same.erasure.no.override.1";
2339 log.error(pos,
2340 key,
2341 sym, sym.location(),
2342 m2, m2.location(),
2343 m1, m1.location());
2344 return;
2345 }
2346 }
2347 }
2348
2349 if (!overridesAny) {
2350 for (MethodSymbol m: potentiallyAmbiguousList) {
2351 checkPotentiallyAmbiguousOverloads(pos, site, sym, m);
2352 }
2353 }
2354 }
2355
2356 /** Check that all static methods accessible from 'site' are
2357 * mutually compatible (JLS 8.4.8).
2358 *
2359 * @param pos Position to be used for error reporting.
2360 * @param site The class whose methods are checked.
2361 * @param sym The method symbol to be checked.
2362 */
2363 void checkHideClashes(DiagnosticPosition pos, Type site, MethodSymbol sym) {
2364 ClashFilter cf = new ClashFilter(site);
2365 //for each method m1 that is a member of 'site'...
2366 for (Symbol s : types.membersClosure(site, true).getSymbolsByName(sym.name, cf)) {
2367 //if (i) the signature of 'sym' is not a subsignature of m1 (seen as
2368 //a member of 'site') and (ii) 'sym' has the same erasure as m1, issue an error
2369 if (!types.isSubSignature(sym.type, types.memberType(site, s), allowStrictMethodClashCheck)) {
2370 if (types.hasSameArgs(s.erasure(types), sym.erasure(types))) {
2371 log.error(pos,
2372 "name.clash.same.erasure.no.hide",
2373 sym, sym.location(),
2374 s, s.location());
2375 return;
2376 } else {
2377 checkPotentiallyAmbiguousOverloads(pos, site, sym, (MethodSymbol)s);
2378 }
2379 }
2380 }
2381 }
2382
2383 //where
2384 private class ClashFilter implements Filter<Symbol> {
2385
2386 Type site;
2387
2388 ClashFilter(Type site) {
2389 this.site = site;
2390 }
2391
2392 boolean shouldSkip(Symbol s) {
2393 return (s.flags() & CLASH) != 0 &&
2394 s.owner == site.tsym;
2395 }
2396
2397 public boolean accepts(Symbol s) {
2398 return s.kind == MTH &&
2399 (s.flags() & SYNTHETIC) == 0 &&
2400 !shouldSkip(s) &&
2401 s.isInheritedIn(site.tsym, types) &&
2402 !s.isConstructor();
2403 }
2404 }
2405
2406 void checkDefaultMethodClashes(DiagnosticPosition pos, Type site) {
2407 DefaultMethodClashFilter dcf = new DefaultMethodClashFilter(site);
2408 for (Symbol m : types.membersClosure(site, false).getSymbols(dcf)) {
2409 Assert.check(m.kind == MTH);
2410 List<MethodSymbol> prov = types.interfaceCandidates(site, (MethodSymbol)m);
2411 if (prov.size() > 1) {
2412 ListBuffer<Symbol> abstracts = new ListBuffer<>();
2413 ListBuffer<Symbol> defaults = new ListBuffer<>();
2414 for (MethodSymbol provSym : prov) {
2415 if ((provSym.flags() & DEFAULT) != 0) {
2416 defaults = defaults.append(provSym);
2417 } else if ((provSym.flags() & ABSTRACT) != 0) {
2418 abstracts = abstracts.append(provSym);
2419 }
2420 if (defaults.nonEmpty() && defaults.size() + abstracts.size() >= 2) {
2421 //strong semantics - issue an error if two sibling interfaces
2422 //have two override-equivalent defaults - or if one is abstract
2423 //and the other is default
2424 String errKey;
2425 Symbol s1 = defaults.first();
2426 Symbol s2;
2427 if (defaults.size() > 1) {
2428 errKey = "types.incompatible.unrelated.defaults";
2429 s2 = defaults.toList().tail.head;
2430 } else {
2431 errKey = "types.incompatible.abstract.default";
2432 s2 = abstracts.first();
2433 }
2434 log.error(pos, errKey,
2435 Kinds.kindName(site.tsym), site,
2436 m.name, types.memberType(site, m).getParameterTypes(),
2437 s1.location(), s2.location());
2438 break;
2439 }
2440 }
2441 }
2442 }
2443 }
2444
2445 //where
2446 private class DefaultMethodClashFilter implements Filter<Symbol> {
2447
2448 Type site;
2449
2450 DefaultMethodClashFilter(Type site) {
2451 this.site = site;
2452 }
2453
2454 public boolean accepts(Symbol s) {
2455 return s.kind == MTH &&
2456 (s.flags() & DEFAULT) != 0 &&
2457 s.isInheritedIn(site.tsym, types) &&
2458 !s.isConstructor();
2459 }
2460 }
2461
2462 /**
2463 * Report warnings for potentially ambiguous method declarations. Two declarations
2464 * are potentially ambiguous if they feature two unrelated functional interface
2465 * in same argument position (in which case, a call site passing an implicit
2466 * lambda would be ambiguous).
2467 */
2468 void checkPotentiallyAmbiguousOverloads(DiagnosticPosition pos, Type site,
2469 MethodSymbol msym1, MethodSymbol msym2) {
2470 if (msym1 != msym2 &&
2471 allowDefaultMethods &&
2472 lint.isEnabled(LintCategory.OVERLOADS) &&
2473 (msym1.flags() & POTENTIALLY_AMBIGUOUS) == 0 &&
2474 (msym2.flags() & POTENTIALLY_AMBIGUOUS) == 0) {
2475 Type mt1 = types.memberType(site, msym1);
2476 Type mt2 = types.memberType(site, msym2);
2477 //if both generic methods, adjust type variables
2478 if (mt1.hasTag(FORALL) && mt2.hasTag(FORALL) &&
2479 types.hasSameBounds((ForAll)mt1, (ForAll)mt2)) {
2480 mt2 = types.subst(mt2, ((ForAll)mt2).tvars, ((ForAll)mt1).tvars);
2481 }
2482 //expand varargs methods if needed
2483 int maxLength = Math.max(mt1.getParameterTypes().length(), mt2.getParameterTypes().length());
2484 List<Type> args1 = rs.adjustArgs(mt1.getParameterTypes(), msym1, maxLength, true);
2485 List<Type> args2 = rs.adjustArgs(mt2.getParameterTypes(), msym2, maxLength, true);
2486 //if arities don't match, exit
2487 if (args1.length() != args2.length()) return;
2488 boolean potentiallyAmbiguous = false;
2489 while (args1.nonEmpty() && args2.nonEmpty()) {
2490 Type s = args1.head;
2491 Type t = args2.head;
2492 if (!types.isSubtype(t, s) && !types.isSubtype(s, t)) {
2493 if (types.isFunctionalInterface(s) && types.isFunctionalInterface(t) &&
2494 types.findDescriptorType(s).getParameterTypes().length() > 0 &&
2495 types.findDescriptorType(s).getParameterTypes().length() ==
2496 types.findDescriptorType(t).getParameterTypes().length()) {
2497 potentiallyAmbiguous = true;
2498 } else {
2499 break;
2500 }
2501 }
2502 args1 = args1.tail;
2503 args2 = args2.tail;
2504 }
2505 if (potentiallyAmbiguous) {
2506 //we found two incompatible functional interfaces with same arity
2507 //this means a call site passing an implicit lambda would be ambigiuous
2508 msym1.flags_field |= POTENTIALLY_AMBIGUOUS;
2509 msym2.flags_field |= POTENTIALLY_AMBIGUOUS;
2510 log.warning(LintCategory.OVERLOADS, pos, "potentially.ambiguous.overload",
2511 msym1, msym1.location(),
2512 msym2, msym2.location());
2513 return;
2514 }
2515 }
2516 }
2517
2518 void checkElemAccessFromSerializableLambda(final JCTree tree) {
2519 if (warnOnAccessToSensitiveMembers) {
2520 Symbol sym = TreeInfo.symbol(tree);
2521 if (!sym.kind.matches(KindSelector.VAL_MTH)) {
2522 return;
2523 }
2524
2525 if (sym.kind == VAR) {
2526 if ((sym.flags() & PARAMETER) != 0 ||
2527 sym.isLocal() ||
2528 sym.name == names._this ||
2529 sym.name == names._super) {
2530 return;
2531 }
2532 }
2533
2534 if (!types.isSubtype(sym.owner.type, syms.serializableType) &&
2535 isEffectivelyNonPublic(sym)) {
2536 log.warning(tree.pos(),
2537 "access.to.sensitive.member.from.serializable.element", sym);
2538 }
2539 }
2540 }
2541
2542 private boolean isEffectivelyNonPublic(Symbol sym) {
2543 if (sym.packge() == syms.rootPackage) {
2544 return false;
2545 }
2546
2547 while (sym.kind != PCK) {
2548 if ((sym.flags() & PUBLIC) == 0) {
2549 return true;
2550 }
2551 sym = sym.owner;
2552 }
2553 return false;
2554 }
2555
2556 /** Report a conflict between a user symbol and a synthetic symbol.
2557 */
2558 private void syntheticError(DiagnosticPosition pos, Symbol sym) {
2559 if (!sym.type.isErroneous()) {
2560 if (warnOnSyntheticConflicts) {
2561 log.warning(pos, "synthetic.name.conflict", sym, sym.location());
2562 }
2563 else {
2564 log.error(pos, "synthetic.name.conflict", sym, sym.location());
2565 }
2566 }
2567 }
2568
2569 /** Check that class c does not implement directly or indirectly
2570 * the same parameterized interface with two different argument lists.
2571 * @param pos Position to be used for error reporting.
2572 * @param type The type whose interfaces are checked.
2573 */
2574 void checkClassBounds(DiagnosticPosition pos, Type type) {
2575 checkClassBounds(pos, new HashMap<TypeSymbol,Type>(), type);
2576 }
2577 //where
2578 /** Enter all interfaces of type `type' into the hash table `seensofar'
2579 * with their class symbol as key and their type as value. Make
2580 * sure no class is entered with two different types.
2581 */
2582 void checkClassBounds(DiagnosticPosition pos,
2583 Map<TypeSymbol,Type> seensofar,
2584 Type type) {
2585 if (type.isErroneous()) return;
2586 for (List<Type> l = types.interfaces(type); l.nonEmpty(); l = l.tail) {
2587 Type it = l.head;
2588 Type oldit = seensofar.put(it.tsym, it);
2589 if (oldit != null) {
2590 List<Type> oldparams = oldit.allparams();
2591 List<Type> newparams = it.allparams();
2592 if (!types.containsTypeEquivalent(oldparams, newparams))
2593 log.error(pos, "cant.inherit.diff.arg",
2594 it.tsym, Type.toString(oldparams),
2595 Type.toString(newparams));
2596 }
2597 checkClassBounds(pos, seensofar, it);
2598 }
2599 Type st = types.supertype(type);
2600 if (st != Type.noType) checkClassBounds(pos, seensofar, st);
2601 }
2602
2603 /** Enter interface into into set.
2604 * If it existed already, issue a "repeated interface" error.
2605 */
2606 void checkNotRepeated(DiagnosticPosition pos, Type it, Set<Type> its) {
2607 if (its.contains(it))
2608 log.error(pos, "repeated.interface");
2609 else {
2610 its.add(it);
2611 }
2612 }
2613
2614 /* *************************************************************************
2615 * Check annotations
2616 **************************************************************************/
2617
2618 /**
2619 * Recursively validate annotations values
2620 */
2621 void validateAnnotationTree(JCTree tree) {
2622 class AnnotationValidator extends TreeScanner {
2623 @Override
2624 public void visitAnnotation(JCAnnotation tree) {
2625 if (!tree.type.isErroneous()) {
2626 super.visitAnnotation(tree);
2627 validateAnnotation(tree);
2628 }
2629 }
2630 }
2631 tree.accept(new AnnotationValidator());
2632 }
2633
2634 /**
2635 * {@literal
2636 * Annotation types are restricted to primitives, String, an
2637 * enum, an annotation, Class, Class<?>, Class<? extends
2638 * Anything>, arrays of the preceding.
2639 * }
2640 */
2641 void validateAnnotationType(JCTree restype) {
2642 // restype may be null if an error occurred, so don't bother validating it
2643 if (restype != null) {
2644 validateAnnotationType(restype.pos(), restype.type);
2645 }
2646 }
2647
2648 void validateAnnotationType(DiagnosticPosition pos, Type type) {
2649 if (type.isPrimitive()) return;
2650 if (types.isSameType(type, syms.stringType)) return;
2651 if ((type.tsym.flags() & Flags.ENUM) != 0) return;
2652 if ((type.tsym.flags() & Flags.ANNOTATION) != 0) return;
2653 if (types.cvarLowerBound(type).tsym == syms.classType.tsym) return;
2654 if (types.isArray(type) && !types.isArray(types.elemtype(type))) {
2655 validateAnnotationType(pos, types.elemtype(type));
2656 return;
2657 }
2658 log.error(pos, "invalid.annotation.member.type");
2659 }
2660
2661 /**
2662 * "It is also a compile-time error if any method declared in an
2663 * annotation type has a signature that is override-equivalent to
2664 * that of any public or protected method declared in class Object
2665 * or in the interface annotation.Annotation."
2666 *
2667 * @jls 9.6 Annotation Types
2668 */
2669 void validateAnnotationMethod(DiagnosticPosition pos, MethodSymbol m) {
2670 for (Type sup = syms.annotationType; sup.hasTag(CLASS); sup = types.supertype(sup)) {
2671 Scope s = sup.tsym.members();
2672 for (Symbol sym : s.getSymbolsByName(m.name)) {
2673 if (sym.kind == MTH &&
2674 (sym.flags() & (PUBLIC | PROTECTED)) != 0 &&
2675 types.overrideEquivalent(m.type, sym.type))
2676 log.error(pos, "intf.annotation.member.clash", sym, sup);
2677 }
2678 }
2679 }
2680
2681 /** Check the annotations of a symbol.
2682 */
2683 public void validateAnnotations(List<JCAnnotation> annotations, Symbol s) {
2684 for (JCAnnotation a : annotations)
2685 validateAnnotation(a, s);
2686 }
2687
2688 /** Check the type annotations.
2689 */
2690 public void validateTypeAnnotations(List<JCAnnotation> annotations, boolean isTypeParameter) {
2691 for (JCAnnotation a : annotations)
2692 validateTypeAnnotation(a, isTypeParameter);
2693 }
2694
2695 /** Check an annotation of a symbol.
2696 */
2697 private void validateAnnotation(JCAnnotation a, Symbol s) {
2698 validateAnnotationTree(a);
2699
2700 if (!annotationApplicable(a, s))
2701 log.error(a.pos(), "annotation.type.not.applicable");
2702
2703 if (a.annotationType.type.tsym == syms.functionalInterfaceType.tsym) {
2704 if (s.kind != TYP) {
2705 log.error(a.pos(), "bad.functional.intf.anno");
2706 } else if (!s.isInterface() || (s.flags() & ANNOTATION) != 0) {
2707 log.error(a.pos(), "bad.functional.intf.anno.1", diags.fragment("not.a.functional.intf", s));
2708 }
2709 }
2710 }
2711
2712 public void validateTypeAnnotation(JCAnnotation a, boolean isTypeParameter) {
2713 Assert.checkNonNull(a.type);
2714 validateAnnotationTree(a);
2715
2716 if (a.hasTag(TYPE_ANNOTATION) &&
2717 !a.annotationType.type.isErroneous() &&
2718 !isTypeAnnotation(a, isTypeParameter)) {
2719 log.error(a.pos(), "annotation.type.not.applicable");
2720 }
2721 }
2722
2723 /**
2724 * Validate the proposed container 'repeatable' on the
2725 * annotation type symbol 's'. Report errors at position
2726 * 'pos'.
2727 *
2728 * @param s The (annotation)type declaration annotated with a @Repeatable
2729 * @param repeatable the @Repeatable on 's'
2730 * @param pos where to report errors
2731 */
2732 public void validateRepeatable(TypeSymbol s, Attribute.Compound repeatable, DiagnosticPosition pos) {
2733 Assert.check(types.isSameType(repeatable.type, syms.repeatableType));
2734
2735 Type t = null;
2736 List<Pair<MethodSymbol,Attribute>> l = repeatable.values;
2737 if (!l.isEmpty()) {
2738 Assert.check(l.head.fst.name == names.value);
2739 t = ((Attribute.Class)l.head.snd).getValue();
2740 }
2741
2742 if (t == null) {
2743 // errors should already have been reported during Annotate
2744 return;
2745 }
2746
2747 validateValue(t.tsym, s, pos);
2748 validateRetention(t.tsym, s, pos);
2749 validateDocumented(t.tsym, s, pos);
2750 validateInherited(t.tsym, s, pos);
2751 validateTarget(t.tsym, s, pos);
2752 validateDefault(t.tsym, pos);
2753 }
2754
2755 private void validateValue(TypeSymbol container, TypeSymbol contained, DiagnosticPosition pos) {
2756 Symbol sym = container.members().findFirst(names.value);
2757 if (sym != null && sym.kind == MTH) {
2758 MethodSymbol m = (MethodSymbol) sym;
2759 Type ret = m.getReturnType();
2760 if (!(ret.hasTag(ARRAY) && types.isSameType(((ArrayType)ret).elemtype, contained.type))) {
2761 log.error(pos, "invalid.repeatable.annotation.value.return",
2762 container, ret, types.makeArrayType(contained.type));
2763 }
2764 } else {
2765 log.error(pos, "invalid.repeatable.annotation.no.value", container);
2766 }
2767 }
2768
2769 private void validateRetention(Symbol container, Symbol contained, DiagnosticPosition pos) {
2770 Attribute.RetentionPolicy containerRetention = types.getRetention(container);
2771 Attribute.RetentionPolicy containedRetention = types.getRetention(contained);
2772
2773 boolean error = false;
2774 switch (containedRetention) {
2775 case RUNTIME:
2776 if (containerRetention != Attribute.RetentionPolicy.RUNTIME) {
2777 error = true;
2778 }
2779 break;
2780 case CLASS:
2781 if (containerRetention == Attribute.RetentionPolicy.SOURCE) {
2782 error = true;
2783 }
2784 }
2785 if (error ) {
2786 log.error(pos, "invalid.repeatable.annotation.retention",
2787 container, containerRetention,
2788 contained, containedRetention);
2789 }
2790 }
2791
2792 private void validateDocumented(Symbol container, Symbol contained, DiagnosticPosition pos) {
2793 if (contained.attribute(syms.documentedType.tsym) != null) {
2794 if (container.attribute(syms.documentedType.tsym) == null) {
2795 log.error(pos, "invalid.repeatable.annotation.not.documented", container, contained);
2796 }
2797 }
2798 }
2799
2800 private void validateInherited(Symbol container, Symbol contained, DiagnosticPosition pos) {
2801 if (contained.attribute(syms.inheritedType.tsym) != null) {
2802 if (container.attribute(syms.inheritedType.tsym) == null) {
2803 log.error(pos, "invalid.repeatable.annotation.not.inherited", container, contained);
2804 }
2805 }
2806 }
2807
2808 private void validateTarget(Symbol container, Symbol contained, DiagnosticPosition pos) {
2809 // The set of targets the container is applicable to must be a subset
2810 // (with respect to annotation target semantics) of the set of targets
2811 // the contained is applicable to. The target sets may be implicit or
2812 // explicit.
2813
2814 Set<Name> containerTargets;
2815 Attribute.Array containerTarget = getAttributeTargetAttribute(container);
2816 if (containerTarget == null) {
2817 containerTargets = getDefaultTargetSet();
2818 } else {
2819 containerTargets = new HashSet<>();
2820 for (Attribute app : containerTarget.values) {
2821 if (!(app instanceof Attribute.Enum)) {
2822 continue; // recovery
2823 }
2824 Attribute.Enum e = (Attribute.Enum)app;
2825 containerTargets.add(e.value.name);
2826 }
2827 }
2828
2829 Set<Name> containedTargets;
2830 Attribute.Array containedTarget = getAttributeTargetAttribute(contained);
2831 if (containedTarget == null) {
2832 containedTargets = getDefaultTargetSet();
2833 } else {
2834 containedTargets = new HashSet<>();
2835 for (Attribute app : containedTarget.values) {
2836 if (!(app instanceof Attribute.Enum)) {
2837 continue; // recovery
2838 }
2839 Attribute.Enum e = (Attribute.Enum)app;
2840 containedTargets.add(e.value.name);
2841 }
2842 }
2843
2844 if (!isTargetSubsetOf(containerTargets, containedTargets)) {
2845 log.error(pos, "invalid.repeatable.annotation.incompatible.target", container, contained);
2846 }
2847 }
2848
2849 /* get a set of names for the default target */
2850 private Set<Name> getDefaultTargetSet() {
2851 if (defaultTargets == null) {
2852 Set<Name> targets = new HashSet<>();
2853 targets.add(names.ANNOTATION_TYPE);
2854 targets.add(names.CONSTRUCTOR);
2855 targets.add(names.FIELD);
2856 targets.add(names.LOCAL_VARIABLE);
2857 targets.add(names.METHOD);
2858 targets.add(names.PACKAGE);
2859 targets.add(names.PARAMETER);
2860 targets.add(names.TYPE);
2861
2862 defaultTargets = java.util.Collections.unmodifiableSet(targets);
2863 }
2864
2865 return defaultTargets;
2866 }
2867 private Set<Name> defaultTargets;
2868
2869
2870 /** Checks that s is a subset of t, with respect to ElementType
2871 * semantics, specifically {ANNOTATION_TYPE} is a subset of {TYPE},
2872 * and {TYPE_USE} covers the set {ANNOTATION_TYPE, TYPE, TYPE_USE,
2873 * TYPE_PARAMETER}.
2874 */
2875 private boolean isTargetSubsetOf(Set<Name> s, Set<Name> t) {
2876 // Check that all elements in s are present in t
2877 for (Name n2 : s) {
2878 boolean currentElementOk = false;
2879 for (Name n1 : t) {
2880 if (n1 == n2) {
2881 currentElementOk = true;
2882 break;
2883 } else if (n1 == names.TYPE && n2 == names.ANNOTATION_TYPE) {
2884 currentElementOk = true;
2885 break;
2886 } else if (n1 == names.TYPE_USE &&
2887 (n2 == names.TYPE ||
2888 n2 == names.ANNOTATION_TYPE ||
2889 n2 == names.TYPE_PARAMETER)) {
2890 currentElementOk = true;
2891 break;
2892 }
2893 }
2894 if (!currentElementOk)
2895 return false;
2896 }
2897 return true;
2898 }
2899
2900 private void validateDefault(Symbol container, DiagnosticPosition pos) {
2901 // validate that all other elements of containing type has defaults
2902 Scope scope = container.members();
2903 for(Symbol elm : scope.getSymbols()) {
2904 if (elm.name != names.value &&
2905 elm.kind == MTH &&
2906 ((MethodSymbol)elm).defaultValue == null) {
2907 log.error(pos,
2908 "invalid.repeatable.annotation.elem.nondefault",
2909 container,
2910 elm);
2911 }
2912 }
2913 }
2914
2915 /** Is s a method symbol that overrides a method in a superclass? */
2916 boolean isOverrider(Symbol s) {
2917 if (s.kind != MTH || s.isStatic())
2918 return false;
2919 MethodSymbol m = (MethodSymbol)s;
2920 TypeSymbol owner = (TypeSymbol)m.owner;
2921 for (Type sup : types.closure(owner.type)) {
2922 if (sup == owner.type)
2923 continue; // skip "this"
2924 Scope scope = sup.tsym.members();
2925 for (Symbol sym : scope.getSymbolsByName(m.name)) {
2926 if (!sym.isStatic() && m.overrides(sym, owner, types, true))
2927 return true;
2928 }
2929 }
2930 return false;
2931 }
2932
2933 /** Is the annotation applicable to types? */
2934 protected boolean isTypeAnnotation(JCAnnotation a, boolean isTypeParameter) {
2935 Attribute.Compound atTarget =
2936 a.annotationType.type.tsym.attribute(syms.annotationTargetType.tsym);
2937 if (atTarget == null) {
2938 // An annotation without @Target is not a type annotation.
2939 return false;
2940 }
2941
2942 Attribute atValue = atTarget.member(names.value);
2943 if (!(atValue instanceof Attribute.Array)) {
2944 return false; // error recovery
2945 }
2946
2947 Attribute.Array arr = (Attribute.Array) atValue;
2948 for (Attribute app : arr.values) {
2949 if (!(app instanceof Attribute.Enum)) {
2950 return false; // recovery
2951 }
2952 Attribute.Enum e = (Attribute.Enum) app;
2953
2954 if (e.value.name == names.TYPE_USE)
2955 return true;
2956 else if (isTypeParameter && e.value.name == names.TYPE_PARAMETER)
2957 return true;
2958 }
2959 return false;
2960 }
2961
2962 /** Is the annotation applicable to the symbol? */
2963 boolean annotationApplicable(JCAnnotation a, Symbol s) {
2964 Attribute.Array arr = getAttributeTargetAttribute(a.annotationType.type.tsym);
2965 Name[] targets;
2966
2967 if (arr == null) {
2968 targets = defaultTargetMetaInfo(a, s);
2969 } else {
2970 // TODO: can we optimize this?
2971 targets = new Name[arr.values.length];
2972 for (int i=0; i<arr.values.length; ++i) {
2973 Attribute app = arr.values[i];
2974 if (!(app instanceof Attribute.Enum)) {
2975 return true; // recovery
2976 }
2977 Attribute.Enum e = (Attribute.Enum) app;
2978 targets[i] = e.value.name;
2979 }
2980 }
2981 for (Name target : targets) {
2982 if (target == names.TYPE)
2983 { if (s.kind == TYP) return true; }
2984 else if (target == names.FIELD)
2985 { if (s.kind == VAR && s.owner.kind != MTH) return true; }
2986 else if (target == names.METHOD)
2987 { if (s.kind == MTH && !s.isConstructor()) return true; }
2988 else if (target == names.PARAMETER)
2989 { if (s.kind == VAR && s.owner.kind == MTH &&
2990 (s.flags() & PARAMETER) != 0)
2991 return true;
2992 }
2993 else if (target == names.CONSTRUCTOR)
2994 { if (s.kind == MTH && s.isConstructor()) return true; }
2995 else if (target == names.LOCAL_VARIABLE)
2996 { if (s.kind == VAR && s.owner.kind == MTH &&
2997 (s.flags() & PARAMETER) == 0)
2998 return true;
2999 }
3000 else if (target == names.ANNOTATION_TYPE)
3001 { if (s.kind == TYP && (s.flags() & ANNOTATION) != 0)
3002 return true;
3003 }
3004 else if (target == names.PACKAGE)
3005 { if (s.kind == PCK) return true; }
3006 else if (target == names.TYPE_USE)
3007 { if (s.kind == TYP || s.kind == VAR ||
3008 (s.kind == MTH && !s.isConstructor() &&
3009 !s.type.getReturnType().hasTag(VOID)) ||
3010 (s.kind == MTH && s.isConstructor()))
3011 return true;
3012 }
3013 else if (target == names.TYPE_PARAMETER)
3014 { if (s.kind == TYP && s.type.hasTag(TYPEVAR))
3015 return true;
3016 }
3017 else
3018 return true; // recovery
3019 }
3020 return false;
3021 }
3022
3023
3024 Attribute.Array getAttributeTargetAttribute(Symbol s) {
3025 Attribute.Compound atTarget =
3026 s.attribute(syms.annotationTargetType.tsym);
3027 if (atTarget == null) return null; // ok, is applicable
3028 Attribute atValue = atTarget.member(names.value);
3029 if (!(atValue instanceof Attribute.Array)) return null; // error recovery
3030 return (Attribute.Array) atValue;
3031 }
3032
3033 private final Name[] dfltTargetMeta;
3034 private Name[] defaultTargetMetaInfo(JCAnnotation a, Symbol s) {
3035 return dfltTargetMeta;
3036 }
3037
3038 /** Check an annotation value.
3039 *
3040 * @param a The annotation tree to check
3041 * @return true if this annotation tree is valid, otherwise false
3042 */
3043 public boolean validateAnnotationDeferErrors(JCAnnotation a) {
3044 boolean res = false;
3045 final Log.DiagnosticHandler diagHandler = new Log.DiscardDiagnosticHandler(log);
3046 try {
3047 res = validateAnnotation(a);
3048 } finally {
3049 log.popDiagnosticHandler(diagHandler);
3050 }
3051 return res;
3052 }
3053
3054 private boolean validateAnnotation(JCAnnotation a) {
3055 boolean isValid = true;
3056 // collect an inventory of the annotation elements
3057 Set<MethodSymbol> members = new LinkedHashSet<>();
3058 for (Symbol sym : a.annotationType.type.tsym.members().getSymbols(NON_RECURSIVE))
3059 if (sym.kind == MTH && sym.name != names.clinit &&
3060 (sym.flags() & SYNTHETIC) == 0)
3061 members.add((MethodSymbol) sym);
3062
3063 // remove the ones that are assigned values
3064 for (JCTree arg : a.args) {
3065 if (!arg.hasTag(ASSIGN)) continue; // recovery
3066 JCAssign assign = (JCAssign) arg;
3067 Symbol m = TreeInfo.symbol(assign.lhs);
3068 if (m == null || m.type.isErroneous()) continue;
3069 if (!members.remove(m)) {
3070 isValid = false;
3071 log.error(assign.lhs.pos(), "duplicate.annotation.member.value",
3072 m.name, a.type);
3073 }
3074 }
3075
3076 // all the remaining ones better have default values
3077 List<Name> missingDefaults = List.nil();
3078 for (MethodSymbol m : members) {
3079 if (m.defaultValue == null && !m.type.isErroneous()) {
3080 missingDefaults = missingDefaults.append(m.name);
3081 }
3082 }
3083 missingDefaults = missingDefaults.reverse();
3084 if (missingDefaults.nonEmpty()) {
3085 isValid = false;
3086 String key = (missingDefaults.size() > 1)
3087 ? "annotation.missing.default.value.1"
3088 : "annotation.missing.default.value";
3089 log.error(a.pos(), key, a.type, missingDefaults);
3090 }
3091
3092 // special case: java.lang.annotation.Target must not have
3093 // repeated values in its value member
3094 if (a.annotationType.type.tsym != syms.annotationTargetType.tsym ||
3095 a.args.tail == null)
3096 return isValid;
3097
3098 if (!a.args.head.hasTag(ASSIGN)) return false; // error recovery
3099 JCAssign assign = (JCAssign) a.args.head;
3100 Symbol m = TreeInfo.symbol(assign.lhs);
3101 if (m.name != names.value) return false;
3102 JCTree rhs = assign.rhs;
3103 if (!rhs.hasTag(NEWARRAY)) return false;
3104 JCNewArray na = (JCNewArray) rhs;
3105 Set<Symbol> targets = new HashSet<>();
3106 for (JCTree elem : na.elems) {
3107 if (!targets.add(TreeInfo.symbol(elem))) {
3108 isValid = false;
3109 log.error(elem.pos(), "repeated.annotation.target");
3110 }
3111 }
3112 return isValid;
3113 }
3114
3115 void checkDeprecatedAnnotation(DiagnosticPosition pos, Symbol s) {
3116 if (lint.isEnabled(LintCategory.DEP_ANN) &&
3117 (s.flags() & DEPRECATED) != 0 &&
3118 !syms.deprecatedType.isErroneous() &&
3119 s.attribute(syms.deprecatedType.tsym) == null) {
3120 log.warning(LintCategory.DEP_ANN,
3121 pos, "missing.deprecated.annotation");
3122 }
3123 }
3124
3125 void checkDeprecated(final DiagnosticPosition pos, final Symbol other, final Symbol s) {
3126 if ((s.flags() & DEPRECATED) != 0 &&
3127 (other.flags() & DEPRECATED) == 0 &&
3128 s.outermostClass() != other.outermostClass()) {
3129 deferredLintHandler.report(new DeferredLintHandler.LintLogger() {
3130 @Override
3131 public void report() {
3132 warnDeprecated(pos, s);
3133 }
3134 });
3135 }
3136 }
3137
3138 void checkSunAPI(final DiagnosticPosition pos, final Symbol s) {
3139 if ((s.flags() & PROPRIETARY) != 0) {
3140 deferredLintHandler.report(new DeferredLintHandler.LintLogger() {
3141 public void report() {
3142 if (enableSunApiLintControl)
3143 warnSunApi(pos, "sun.proprietary", s);
3144 else
3145 log.mandatoryWarning(pos, "sun.proprietary", s);
3146 }
3147 });
3148 }
3149 }
3150
3151 void checkProfile(final DiagnosticPosition pos, final Symbol s) {
3152 if (profile != Profile.DEFAULT && (s.flags() & NOT_IN_PROFILE) != 0) {
3153 log.error(pos, "not.in.profile", s, profile);
3154 }
3155 }
3156
3157 /* *************************************************************************
3158 * Check for recursive annotation elements.
3159 **************************************************************************/
3160
3161 /** Check for cycles in the graph of annotation elements.
3162 */
3163 void checkNonCyclicElements(JCClassDecl tree) {
3164 if ((tree.sym.flags_field & ANNOTATION) == 0) return;
3165 Assert.check((tree.sym.flags_field & LOCKED) == 0);
3166 try {
3167 tree.sym.flags_field |= LOCKED;
3168 for (JCTree def : tree.defs) {
3169 if (!def.hasTag(METHODDEF)) continue;
3170 JCMethodDecl meth = (JCMethodDecl)def;
3171 checkAnnotationResType(meth.pos(), meth.restype.type);
3172 }
3173 } finally {
3174 tree.sym.flags_field &= ~LOCKED;
3175 tree.sym.flags_field |= ACYCLIC_ANN;
3176 }
3177 }
3178
3179 void checkNonCyclicElementsInternal(DiagnosticPosition pos, TypeSymbol tsym) {
3180 if ((tsym.flags_field & ACYCLIC_ANN) != 0)
3181 return;
3182 if ((tsym.flags_field & LOCKED) != 0) {
3183 log.error(pos, "cyclic.annotation.element");
3184 return;
3185 }
3186 try {
3187 tsym.flags_field |= LOCKED;
3188 for (Symbol s : tsym.members().getSymbols(NON_RECURSIVE)) {
3189 if (s.kind != MTH)
3190 continue;
3191 checkAnnotationResType(pos, ((MethodSymbol)s).type.getReturnType());
3192 }
3193 } finally {
3194 tsym.flags_field &= ~LOCKED;
3195 tsym.flags_field |= ACYCLIC_ANN;
3196 }
3197 }
3198
3199 void checkAnnotationResType(DiagnosticPosition pos, Type type) {
3200 switch (type.getTag()) {
3201 case CLASS:
3202 if ((type.tsym.flags() & ANNOTATION) != 0)
3203 checkNonCyclicElementsInternal(pos, type.tsym);
3204 break;
3205 case ARRAY:
3206 checkAnnotationResType(pos, types.elemtype(type));
3207 break;
3208 default:
3209 break; // int etc
3210 }
3211 }
3212
3213 /* *************************************************************************
3214 * Check for cycles in the constructor call graph.
3215 **************************************************************************/
3216
3217 /** Check for cycles in the graph of constructors calling other
3218 * constructors.
3219 */
3220 void checkCyclicConstructors(JCClassDecl tree) {
3221 Map<Symbol,Symbol> callMap = new HashMap<>();
3222
3223 // enter each constructor this-call into the map
3224 for (List<JCTree> l = tree.defs; l.nonEmpty(); l = l.tail) {
3225 JCMethodInvocation app = TreeInfo.firstConstructorCall(l.head);
3226 if (app == null) continue;
3227 JCMethodDecl meth = (JCMethodDecl) l.head;
3228 if (TreeInfo.name(app.meth) == names._this) {
3229 callMap.put(meth.sym, TreeInfo.symbol(app.meth));
3230 } else {
3231 meth.sym.flags_field |= ACYCLIC;
3232 }
3233 }
3234
3235 // Check for cycles in the map
3236 Symbol[] ctors = new Symbol[0];
3237 ctors = callMap.keySet().toArray(ctors);
3238 for (Symbol caller : ctors) {
3239 checkCyclicConstructor(tree, caller, callMap);
3240 }
3241 }
3242
3243 /** Look in the map to see if the given constructor is part of a
3244 * call cycle.
3245 */
3246 private void checkCyclicConstructor(JCClassDecl tree, Symbol ctor,
3247 Map<Symbol,Symbol> callMap) {
3248 if (ctor != null && (ctor.flags_field & ACYCLIC) == 0) {
3249 if ((ctor.flags_field & LOCKED) != 0) {
3250 log.error(TreeInfo.diagnosticPositionFor(ctor, tree),
3251 "recursive.ctor.invocation");
3252 } else {
3253 ctor.flags_field |= LOCKED;
3254 checkCyclicConstructor(tree, callMap.remove(ctor), callMap);
3255 ctor.flags_field &= ~LOCKED;
3256 }
3257 ctor.flags_field |= ACYCLIC;
3258 }
3259 }
3260
3261 /* *************************************************************************
3262 * Miscellaneous
3263 **************************************************************************/
3264
3265 /**
3266 * Check for division by integer constant zero
3267 * @param pos Position for error reporting.
3268 * @param operator The operator for the expression
3269 * @param operand The right hand operand for the expression
3270 */
3271 void checkDivZero(final DiagnosticPosition pos, Symbol operator, Type operand) {
3272 if (operand.constValue() != null
3273 && operand.getTag().isSubRangeOf(LONG)
3274 && ((Number) (operand.constValue())).longValue() == 0) {
3275 int opc = ((OperatorSymbol)operator).opcode;
3276 if (opc == ByteCodes.idiv || opc == ByteCodes.imod
3277 || opc == ByteCodes.ldiv || opc == ByteCodes.lmod) {
3278 deferredLintHandler.report(new DeferredLintHandler.LintLogger() {
3279 @Override
3280 public void report() {
3281 warnDivZero(pos);
3282 }
3283 });
3284 }
3285 }
3286 }
3287
3288 /**
3289 * Check for empty statements after if
3290 */
3291 void checkEmptyIf(JCIf tree) {
3292 if (tree.thenpart.hasTag(SKIP) && tree.elsepart == null &&
3293 lint.isEnabled(LintCategory.EMPTY))
3294 log.warning(LintCategory.EMPTY, tree.thenpart.pos(), "empty.if");
3295 }
3296
3297 /** Check that symbol is unique in given scope.
3298 * @param pos Position for error reporting.
3299 * @param sym The symbol.
3300 * @param s The scope.
3301 */
3302 boolean checkUnique(DiagnosticPosition pos, Symbol sym, Scope s) {
3303 if (sym.type.isErroneous())
3304 return true;
3305 if (sym.owner.name == names.any) return false;
3306 for (Symbol byName : s.getSymbolsByName(sym.name, NON_RECURSIVE)) {
3307 if (sym != byName &&
3308 (byName.flags() & CLASH) == 0 &&
3309 sym.kind == byName.kind &&
3310 sym.name != names.error &&
3311 (sym.kind != MTH ||
3312 types.hasSameArgs(sym.type, byName.type) ||
3313 types.hasSameArgs(types.erasure(sym.type), types.erasure(byName.type)))) {
3314 if ((sym.flags() & VARARGS) != (byName.flags() & VARARGS)) {
3315 varargsDuplicateError(pos, sym, byName);
3316 return true;
3317 } else if (sym.kind == MTH && !types.hasSameArgs(sym.type, byName.type, false)) {
3318 duplicateErasureError(pos, sym, byName);
3319 sym.flags_field |= CLASH;
3320 return true;
3321 } else {
3322 duplicateError(pos, byName);
3323 return false;
3324 }
3325 }
3326 }
3327 return true;
3328 }
3329
3330 /** Report duplicate declaration error.
3331 */
3332 void duplicateErasureError(DiagnosticPosition pos, Symbol sym1, Symbol sym2) {
3333 if (!sym1.type.isErroneous() && !sym2.type.isErroneous()) {
3334 log.error(pos, "name.clash.same.erasure", sym1, sym2);
3335 }
3336 }
3337
3338 /**Check that types imported through the ordinary imports don't clash with types imported
3339 * by other (static or ordinary) imports. Note that two static imports may import two clashing
3340 * types without an error on the imports.
3341 * @param toplevel The toplevel tree for which the test should be performed.
3342 */
3343 void checkImportsUnique(JCCompilationUnit toplevel) {
3344 WriteableScope ordinallyImportedSoFar = WriteableScope.create(toplevel.packge);
3345 WriteableScope staticallyImportedSoFar = WriteableScope.create(toplevel.packge);
3346 WriteableScope topLevelScope = toplevel.toplevelScope;
3347
3348 for (JCTree def : toplevel.defs) {
3349 if (!def.hasTag(IMPORT))
3350 continue;
3351
3352 JCImport imp = (JCImport) def;
3353
3354 if (imp.importScope == null)
3355 continue;
3356
3357 for (Symbol sym : imp.importScope.getSymbols(sym -> sym.kind == TYP)) {
3358 if (imp.isStatic()) {
3359 checkUniqueImport(imp.pos(), ordinallyImportedSoFar, staticallyImportedSoFar, topLevelScope, sym, true);
3360 staticallyImportedSoFar.enter(sym);
3361 } else {
3362 checkUniqueImport(imp.pos(), ordinallyImportedSoFar, staticallyImportedSoFar, topLevelScope, sym, false);
3363 ordinallyImportedSoFar.enter(sym);
3364 }
3365 }
3366
3367 imp.importScope = null;
3368 }
3369 }
3370
3371 /** Check that single-type import is not already imported or top-level defined,
3372 * but make an exception for two single-type imports which denote the same type.
3373 * @param pos Position for error reporting.
3374 * @param ordinallyImportedSoFar A Scope containing types imported so far through
3375 * ordinary imports.
3376 * @param staticallyImportedSoFar A Scope containing types imported so far through
3377 * static imports.
3378 * @param topLevelScope The current file's top-level Scope
3379 * @param sym The symbol.
3380 * @param staticImport Whether or not this was a static import
3381 */
3382 private boolean checkUniqueImport(DiagnosticPosition pos, Scope ordinallyImportedSoFar,
3383 Scope staticallyImportedSoFar, Scope topLevelScope,
3384 Symbol sym, boolean staticImport) {
3385 Filter<Symbol> duplicates = candidate -> candidate != sym && !candidate.type.isErroneous();
3386 Symbol clashing = ordinallyImportedSoFar.findFirst(sym.name, duplicates);
3387 if (clashing == null && !staticImport) {
3388 clashing = staticallyImportedSoFar.findFirst(sym.name, duplicates);
3389 }
3390 if (clashing != null) {
3391 if (staticImport)
3392 log.error(pos, "already.defined.static.single.import", clashing);
3393 else
3394 log.error(pos, "already.defined.single.import", clashing);
3395 return false;
3396 }
3397 clashing = topLevelScope.findFirst(sym.name, duplicates);
3398 if (clashing != null) {
3399 log.error(pos, "already.defined.this.unit", clashing);
3400 return false;
3401 }
3402 return true;
3403 }
3404
3405 /** Check that a qualified name is in canonical form (for import decls).
3406 */
3407 public void checkCanonical(JCTree tree) {
3408 if (!isCanonical(tree))
3409 log.error(tree.pos(), "import.requires.canonical",
3410 TreeInfo.symbol(tree));
3411 }
3412 // where
3413 private boolean isCanonical(JCTree tree) {
3414 while (tree.hasTag(SELECT)) {
3415 JCFieldAccess s = (JCFieldAccess) tree;
3416 if (s.sym.owner != TreeInfo.symbol(s.selected))
3417 return false;
3418 tree = s.selected;
3419 }
3420 return true;
3421 }
3422
3423 /** Check that an auxiliary class is not accessed from any other file than its own.
3424 */
3425 void checkForBadAuxiliaryClassAccess(DiagnosticPosition pos, Env<AttrContext> env, ClassSymbol c) {
3426 if (lint.isEnabled(Lint.LintCategory.AUXILIARYCLASS) &&
3427 (c.flags() & AUXILIARY) != 0 &&
3428 rs.isAccessible(env, c) &&
3429 !fileManager.isSameFile(c.sourcefile, env.toplevel.sourcefile))
3430 {
3431 log.warning(pos, "auxiliary.class.accessed.from.outside.of.its.source.file",
3432 c, c.sourcefile);
3433 }
3434 }
3435
3436 private class ConversionWarner extends Warner {
3437 final String uncheckedKey;
3438 final Type found;
3439 final Type expected;
3440 public ConversionWarner(DiagnosticPosition pos, String uncheckedKey, Type found, Type expected) {
3441 super(pos);
3442 this.uncheckedKey = uncheckedKey;
3443 this.found = found;
3444 this.expected = expected;
3445 }
3446
3447 @Override
3448 public void warn(LintCategory lint) {
3449 boolean warned = this.warned;
3450 super.warn(lint);
3451 if (warned) return; // suppress redundant diagnostics
3452 switch (lint) {
3453 case UNCHECKED:
3454 Check.this.warnUnchecked(pos(), "prob.found.req", diags.fragment(uncheckedKey), found, expected);
3455 break;
3456 case VARARGS:
3457 if (method != null &&
3458 method.attribute(syms.trustMeType.tsym) != null &&
3459 isTrustMeAllowedOnMethod(method) &&
3460 !types.isReifiable(method.type.getParameterTypes().last())) {
3461 Check.this.warnUnsafeVararg(pos(), "varargs.unsafe.use.varargs.param", method.params.last());
3462 }
3463 break;
3464 default:
3465 throw new AssertionError("Unexpected lint: " + lint);
3466 }
3467 }
3468 }
3469
3470 public Warner castWarner(DiagnosticPosition pos, Type found, Type expected) {
3471 return new ConversionWarner(pos, "unchecked.cast.to.type", found, expected);
3472 }
3473
3474 public Warner convertWarner(DiagnosticPosition pos, Type found, Type expected) {
3475 return new ConversionWarner(pos, "unchecked.assign", found, expected);
3476 }
3477
3478 public void checkFunctionalInterface(JCClassDecl tree, ClassSymbol cs) {
3479 Compound functionalType = cs.attribute(syms.functionalInterfaceType.tsym);
3480
3481 if (functionalType != null) {
3482 try {
3483 types.findDescriptorSymbol((TypeSymbol)cs);
3484 } catch (Types.FunctionDescriptorLookupError ex) {
3485 DiagnosticPosition pos = tree.pos();
3486 for (JCAnnotation a : tree.getModifiers().annotations) {
3487 if (a.annotationType.type.tsym == syms.functionalInterfaceType.tsym) {
3488 pos = a.pos();
3489 break;
3490 }
3491 }
3492 log.error(pos, "bad.functional.intf.anno.1", ex.getDiagnostic());
3493 }
3494 }
3495 }
3496
3497 public void checkImportsResolvable(final JCCompilationUnit toplevel) {
3498 for (final JCImport imp : toplevel.getImports()) {
3499 if (!imp.staticImport || !imp.qualid.hasTag(SELECT))
3500 continue;
3501 final JCFieldAccess select = (JCFieldAccess) imp.qualid;
3502 final Symbol origin;
3503 if (select.name == names.asterisk || (origin = TreeInfo.symbol(select.selected)) == null || origin.kind != TYP)
3504 continue;
3505
3506 TypeSymbol site = (TypeSymbol) TreeInfo.symbol(select.selected);
3507 if (!checkTypeContainsImportableElement(site, site, toplevel.packge, select.name, new HashSet<Symbol>())) {
3508 log.error(imp.pos(), "cant.resolve.location",
3509 KindName.STATIC,
3510 select.name, List.<Type>nil(), List.<Type>nil(),
3511 Kinds.typeKindName(TreeInfo.symbol(select.selected).type),
3512 TreeInfo.symbol(select.selected).type);
3513 }
3514 }
3515 }
3516
3517 private boolean checkTypeContainsImportableElement(TypeSymbol tsym, TypeSymbol origin, PackageSymbol packge, Name name, Set<Symbol> processed) {
3518 if (tsym == null || !processed.add(tsym))
3519 return false;
3520
3521 // also search through inherited names
3522 if (checkTypeContainsImportableElement(types.supertype(tsym.type).tsym, origin, packge, name, processed))
3523 return true;
3524
3525 for (Type t : types.interfaces(tsym.type))
3526 if (checkTypeContainsImportableElement(t.tsym, origin, packge, name, processed))
3527 return true;
3528
3529 for (Symbol sym : tsym.members().getSymbolsByName(name)) {
3530 if (sym.isStatic() &&
3531 staticImportAccessible(sym, packge) &&
3532 sym.isMemberOf(origin, types)) {
3533 return true;
3534 }
3535 }
3536
3537 return false;
3538 }
3539
3540 // is the sym accessible everywhere in packge?
3541 public boolean staticImportAccessible(Symbol sym, PackageSymbol packge) {
3542 int flags = (int)(sym.flags() & AccessFlags);
3543 switch (flags) {
3544 default:
3545 case PUBLIC:
3546 return true;
3547 case PRIVATE:
3548 return false;
3549 case 0:
3550 case PROTECTED:
3551 return sym.packge() == packge;
3552 }
3553 }
3554
3555 }