1 /*
2 * Copyright (c) 1999, 2016, Oracle and/or its affiliates. All rights reserved.
3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
4 *
5 * This code is free software; you can redistribute it and/or modify it
6 * under the terms of the GNU General Public License version 2 only, as
7 * published by the Free Software Foundation. Oracle designates this
8 * particular file as subject to the "Classpath" exception as provided
9 * by Oracle in the LICENSE file that accompanied this code.
10 *
11 * This code is distributed in the hope that it will be useful, but WITHOUT
12 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
13 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
14 * version 2 for more details (a copy is included in the LICENSE file that
15 * accompanied this code).
16 *
17 * You should have received a copy of the GNU General Public License version
18 * 2 along with this work; if not, write to the Free Software Foundation,
19 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
20 *
21 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
22 * or visit www.oracle.com if you need additional information or have any
23 * questions.
24 */
25
26 package com.sun.tools.javac.comp;
27
28 import java.util.*;
29
30 import javax.tools.JavaFileManager;
31
32 import com.sun.tools.javac.code.*;
33 import com.sun.tools.javac.code.Attribute.Compound;
34 import com.sun.tools.javac.code.Directive.ExportsDirective;
35 import com.sun.tools.javac.code.Directive.RequiresDirective;
36 import com.sun.tools.javac.comp.Annotate.AnnotationTypeMetadata;
37 import com.sun.tools.javac.jvm.*;
38 import com.sun.tools.javac.resources.CompilerProperties.Errors;
39 import com.sun.tools.javac.resources.CompilerProperties.Fragments;
40 import com.sun.tools.javac.resources.CompilerProperties.Warnings;
41 import com.sun.tools.javac.tree.*;
42 import com.sun.tools.javac.util.*;
43 import com.sun.tools.javac.util.JCDiagnostic.DiagnosticFlag;
44 import com.sun.tools.javac.util.JCDiagnostic.DiagnosticPosition;
45 import com.sun.tools.javac.util.List;
46
47 import com.sun.tools.javac.code.Lint;
48 import com.sun.tools.javac.code.Lint.LintCategory;
49 import com.sun.tools.javac.code.Scope.WriteableScope;
50 import com.sun.tools.javac.code.Type.*;
51 import com.sun.tools.javac.code.Symbol.*;
52 import com.sun.tools.javac.comp.DeferredAttr.DeferredAttrContext;
53 import com.sun.tools.javac.comp.Infer.FreeTypeListener;
54 import com.sun.tools.javac.tree.JCTree.*;
55
56 import static com.sun.tools.javac.code.Flags.*;
57 import static com.sun.tools.javac.code.Flags.ANNOTATION;
58 import static com.sun.tools.javac.code.Flags.SYNCHRONIZED;
59 import static com.sun.tools.javac.code.Kinds.*;
60 import static com.sun.tools.javac.code.Kinds.Kind.*;
61 import static com.sun.tools.javac.code.Scope.LookupKind.NON_RECURSIVE;
62 import static com.sun.tools.javac.code.TypeTag.*;
63 import static com.sun.tools.javac.code.TypeTag.WILDCARD;
64
65 import static com.sun.tools.javac.tree.JCTree.Tag.*;
66
67 /** Type checking helper class for the attribution phase.
68 *
69 * <p><b>This is NOT part of any supported API.
70 * If you write code that depends on this, you do so at your own risk.
71 * This code and its internal interfaces are subject to change or
72 * deletion without notice.</b>
73 */
74 public class Check {
75 protected static final Context.Key<Check> checkKey = new Context.Key<>();
76
77 private final Names names;
78 private final Log log;
79 private final Resolve rs;
80 private final Symtab syms;
81 private final Enter enter;
82 private final DeferredAttr deferredAttr;
83 private final Infer infer;
84 private final Types types;
85 private final TypeAnnotations typeAnnotations;
86 private final JCDiagnostic.Factory diags;
87 private final JavaFileManager fileManager;
88 private final Source source;
89 private final Profile profile;
90 private final boolean warnOnAnyAccessToMembers;
91
92 // The set of lint options currently in effect. It is initialized
93 // from the context, and then is set/reset as needed by Attr as it
94 // visits all the various parts of the trees during attribution.
95 private Lint lint;
96
97 // The method being analyzed in Attr - it is set/reset as needed by
98 // Attr as it visits new method declarations.
99 private MethodSymbol method;
100
101 public static Check instance(Context context) {
102 Check instance = context.get(checkKey);
103 if (instance == null)
104 instance = new Check(context);
105 return instance;
106 }
107
108 protected Check(Context context) {
109 context.put(checkKey, this);
110
111 names = Names.instance(context);
112 dfltTargetMeta = new Name[] { names.PACKAGE, names.TYPE,
113 names.FIELD, names.METHOD, names.CONSTRUCTOR,
114 names.ANNOTATION_TYPE, names.LOCAL_VARIABLE, names.PARAMETER};
115 log = Log.instance(context);
116 rs = Resolve.instance(context);
117 syms = Symtab.instance(context);
118 enter = Enter.instance(context);
119 deferredAttr = DeferredAttr.instance(context);
120 infer = Infer.instance(context);
121 types = Types.instance(context);
122 typeAnnotations = TypeAnnotations.instance(context);
123 diags = JCDiagnostic.Factory.instance(context);
124 Options options = Options.instance(context);
125 lint = Lint.instance(context);
126 fileManager = context.get(JavaFileManager.class);
127
128 source = Source.instance(context);
129 allowSimplifiedVarargs = source.allowSimplifiedVarargs();
130 allowDefaultMethods = source.allowDefaultMethods();
131 allowStrictMethodClashCheck = source.allowStrictMethodClashCheck();
132 allowPrivateSafeVarargs = source.allowPrivateSafeVarargs();
133 allowDiamondWithAnonymousClassCreation = source.allowDiamondWithAnonymousClassCreation();
134 warnOnAnyAccessToMembers = options.isSet("warnOnAccessToMembers");
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 verboseRemoval = lint.isEnabled(LintCategory.REMOVAL);
143 boolean verboseUnchecked = lint.isEnabled(LintCategory.UNCHECKED);
144 boolean enforceMandatoryWarnings = true;
145
146 deprecationHandler = new MandatoryWarningHandler(log, verboseDeprecated,
147 enforceMandatoryWarnings, "deprecated", LintCategory.DEPRECATION);
148 removalHandler = new MandatoryWarningHandler(log, verboseRemoval,
149 enforceMandatoryWarnings, "removal", LintCategory.REMOVAL);
150 uncheckedHandler = new MandatoryWarningHandler(log, verboseUnchecked,
151 enforceMandatoryWarnings, "unchecked", LintCategory.UNCHECKED);
152 sunApiHandler = new MandatoryWarningHandler(log, false,
153 enforceMandatoryWarnings, "sunapi", null);
154
155 deferredLintHandler = DeferredLintHandler.instance(context);
156 }
157
158 /** Switch: simplified varargs enabled?
159 */
160 boolean allowSimplifiedVarargs;
161
162 /** Switch: default methods enabled?
163 */
164 boolean allowDefaultMethods;
165
166 /** Switch: should unrelated return types trigger a method clash?
167 */
168 boolean allowStrictMethodClashCheck;
169
170 /** Switch: can the @SafeVarargs annotation be applied to private methods?
171 */
172 boolean allowPrivateSafeVarargs;
173
174 /** Switch: can diamond inference be used in anonymous instance creation ?
175 */
176 boolean allowDiamondWithAnonymousClassCreation;
177
178 /** Character for synthetic names
179 */
180 char syntheticNameChar;
181
182 /** A table mapping flat names of all compiled classes for each module in this run
183 * to their symbols; maintained from outside.
184 */
185 private Map<Pair<ModuleSymbol, Name>,ClassSymbol> compiled = new HashMap<>();
186
187 /** A handler for messages about deprecated usage.
188 */
189 private MandatoryWarningHandler deprecationHandler;
190
191 /** A handler for messages about deprecated-for-removal usage.
192 */
193 private MandatoryWarningHandler removalHandler;
194
195 /** A handler for messages about unchecked or unsafe usage.
196 */
197 private MandatoryWarningHandler uncheckedHandler;
198
199 /** A handler for messages about using proprietary API.
200 */
201 private MandatoryWarningHandler sunApiHandler;
202
203 /** A handler for deferred lint warnings.
204 */
205 private DeferredLintHandler deferredLintHandler;
206
207 /* *************************************************************************
208 * Errors and Warnings
209 **************************************************************************/
210
211 Lint setLint(Lint newLint) {
212 Lint prev = lint;
213 lint = newLint;
214 return prev;
215 }
216
217 MethodSymbol setMethod(MethodSymbol newMethod) {
218 MethodSymbol prev = method;
219 method = newMethod;
220 return prev;
221 }
222
223 /** Warn about deprecated symbol.
224 * @param pos Position to be used for error reporting.
225 * @param sym The deprecated symbol.
226 */
227 void warnDeprecated(DiagnosticPosition pos, Symbol sym) {
228 if (sym.isDeprecatedForRemoval()) {
229 if (!lint.isSuppressed(LintCategory.REMOVAL)) {
230 if (sym.kind == MDL) {
231 removalHandler.report(pos, "has.been.deprecated.for.removal.module", sym);
232 } else {
233 removalHandler.report(pos, "has.been.deprecated.for.removal", sym, sym.location());
234 }
235 }
236 } else if (!lint.isSuppressed(LintCategory.DEPRECATION)) {
237 if (sym.kind == MDL) {
238 deprecationHandler.report(pos, "has.been.deprecated.module", sym);
239 } else {
240 deprecationHandler.report(pos, "has.been.deprecated", sym, sym.location());
241 }
242 }
243 }
244
245 /** Warn about unchecked operation.
246 * @param pos Position to be used for error reporting.
247 * @param msg A string describing the problem.
248 */
249 public void warnUnchecked(DiagnosticPosition pos, String msg, Object... args) {
250 if (!lint.isSuppressed(LintCategory.UNCHECKED))
251 uncheckedHandler.report(pos, msg, args);
252 }
253
254 /** Warn about unsafe vararg method decl.
255 * @param pos Position to be used for error reporting.
256 */
257 void warnUnsafeVararg(DiagnosticPosition pos, String key, Object... args) {
258 if (lint.isEnabled(LintCategory.VARARGS) && allowSimplifiedVarargs)
259 log.warning(LintCategory.VARARGS, pos, key, args);
260 }
261
262 public void warnStatic(DiagnosticPosition pos, String msg, Object... args) {
263 if (lint.isEnabled(LintCategory.STATIC))
264 log.warning(LintCategory.STATIC, pos, msg, args);
265 }
266
267 /** Warn about division by integer constant zero.
268 * @param pos Position to be used for error reporting.
269 */
270 void warnDivZero(DiagnosticPosition pos) {
271 if (lint.isEnabled(LintCategory.DIVZERO))
272 log.warning(LintCategory.DIVZERO, pos, "div.zero");
273 }
274
275 /**
276 * Report any deferred diagnostics.
277 */
278 public void reportDeferredDiagnostics() {
279 deprecationHandler.reportDeferredDiagnostic();
280 removalHandler.reportDeferredDiagnostic();
281 uncheckedHandler.reportDeferredDiagnostic();
282 sunApiHandler.reportDeferredDiagnostic();
283 }
284
285
286 /** Report a failure to complete a class.
287 * @param pos Position to be used for error reporting.
288 * @param ex The failure to report.
289 */
290 public Type completionError(DiagnosticPosition pos, CompletionFailure ex) {
291 log.error(JCDiagnostic.DiagnosticFlag.NON_DEFERRABLE, pos, "cant.access", ex.sym, ex.getDetailValue());
292 if (ex instanceof ClassFinder.BadClassFile) throw new Abort();
293 else return syms.errType;
294 }
295
296 /** Report an error that wrong type tag was found.
297 * @param pos Position to be used for error reporting.
298 * @param required An internationalized string describing the type tag
299 * required.
300 * @param found The type that was found.
301 */
302 Type typeTagError(DiagnosticPosition pos, Object required, Object found) {
303 // this error used to be raised by the parser,
304 // but has been delayed to this point:
305 if (found instanceof Type && ((Type)found).hasTag(VOID)) {
306 log.error(pos, "illegal.start.of.type");
307 return syms.errType;
308 }
309 log.error(pos, "type.found.req", found, required);
310 return types.createErrorType(found instanceof Type ? (Type)found : syms.errType);
311 }
312
313 /** Report an error that symbol cannot be referenced before super
314 * has been called.
315 * @param pos Position to be used for error reporting.
316 * @param sym The referenced symbol.
317 */
318 void earlyRefError(DiagnosticPosition pos, Symbol sym) {
319 log.error(pos, "cant.ref.before.ctor.called", sym);
320 }
321
322 /** Report duplicate declaration error.
323 */
324 void duplicateError(DiagnosticPosition pos, Symbol sym) {
325 if (!sym.type.isErroneous()) {
326 Symbol location = sym.location();
327 if (location.kind == MTH &&
328 ((MethodSymbol)location).isStaticOrInstanceInit()) {
329 log.error(pos, "already.defined.in.clinit", kindName(sym), sym,
330 kindName(sym.location()), kindName(sym.location().enclClass()),
331 sym.location().enclClass());
332 } else {
333 log.error(pos, "already.defined", kindName(sym), sym,
334 kindName(sym.location()), sym.location());
335 }
336 }
337 }
338
339 /** Report array/varargs duplicate declaration
340 */
341 void varargsDuplicateError(DiagnosticPosition pos, Symbol sym1, Symbol sym2) {
342 if (!sym1.type.isErroneous() && !sym2.type.isErroneous()) {
343 log.error(pos, "array.and.varargs", sym1, sym2, sym2.location());
344 }
345 }
346
347 /* ************************************************************************
348 * duplicate declaration checking
349 *************************************************************************/
350
351 /** Check that variable does not hide variable with same name in
352 * immediately enclosing local scope.
353 * @param pos Position for error reporting.
354 * @param v The symbol.
355 * @param s The scope.
356 */
357 void checkTransparentVar(DiagnosticPosition pos, VarSymbol v, Scope s) {
358 for (Symbol sym : s.getSymbolsByName(v.name)) {
359 if (sym.owner != v.owner) break;
360 if (sym.kind == VAR &&
361 sym.owner.kind.matches(KindSelector.VAL_MTH) &&
362 v.name != names.error) {
363 duplicateError(pos, sym);
364 return;
365 }
366 }
367 }
368
369 /** Check that a class or interface does not hide a class or
370 * interface with same name in immediately enclosing local scope.
371 * @param pos Position for error reporting.
372 * @param c The symbol.
373 * @param s The scope.
374 */
375 void checkTransparentClass(DiagnosticPosition pos, ClassSymbol c, Scope s) {
376 for (Symbol sym : s.getSymbolsByName(c.name)) {
377 if (sym.owner != c.owner) break;
378 if (sym.kind == TYP && !sym.type.hasTag(TYPEVAR) &&
379 sym.owner.kind.matches(KindSelector.VAL_MTH) &&
380 c.name != names.error) {
381 duplicateError(pos, sym);
382 return;
383 }
384 }
385 }
386
387 /** Check that class does not have the same name as one of
388 * its enclosing classes, or as a class defined in its enclosing scope.
389 * return true if class is unique in its enclosing scope.
390 * @param pos Position for error reporting.
391 * @param name The class name.
392 * @param s The enclosing scope.
393 */
394 boolean checkUniqueClassName(DiagnosticPosition pos, Name name, Scope s) {
395 for (Symbol sym : s.getSymbolsByName(name, NON_RECURSIVE)) {
396 if (sym.kind == TYP && sym.name != names.error) {
397 duplicateError(pos, sym);
398 return false;
399 }
400 }
401 for (Symbol sym = s.owner; sym != null; sym = sym.owner) {
402 if (sym.kind == TYP && sym.name == name && sym.name != names.error) {
403 duplicateError(pos, sym);
404 return true;
405 }
406 }
407 return true;
408 }
409
410 /* *************************************************************************
411 * Class name generation
412 **************************************************************************/
413
414
415 private Map<Pair<Name, Name>, Integer> localClassNameIndexes = new HashMap<>();
416
417 /** Return name of local class.
418 * This is of the form {@code <enclClass> $ n <classname> }
419 * where
420 * enclClass is the flat name of the enclosing class,
421 * classname is the simple name of the local class
422 */
423 Name localClassName(ClassSymbol c) {
424 Name enclFlatname = c.owner.enclClass().flatname;
425 String enclFlatnameStr = enclFlatname.toString();
426 Pair<Name, Name> key = new Pair<>(enclFlatname, c.name);
427 Integer index = localClassNameIndexes.get(key);
428 for (int i = (index == null) ? 1 : index; ; i++) {
429 Name flatname = names.fromString(enclFlatnameStr
430 + syntheticNameChar + i + c.name);
431 if (getCompiled(c.packge().modle, flatname) == null) {
432 localClassNameIndexes.put(key, i + 1);
433 return flatname;
434 }
435 }
436 }
437
438 void clearLocalClassNameIndexes(ClassSymbol c) {
439 localClassNameIndexes.remove(new Pair<>(
440 c.owner.enclClass().flatname, c.name));
441 }
442
443 public void newRound() {
444 compiled.clear();
445 localClassNameIndexes.clear();
446 }
447
448 public void putCompiled(ClassSymbol csym) {
449 compiled.put(Pair.of(csym.packge().modle, csym.flatname), csym);
450 }
451
452 public ClassSymbol getCompiled(ClassSymbol csym) {
453 return compiled.get(Pair.of(csym.packge().modle, csym.flatname));
454 }
455
456 public ClassSymbol getCompiled(ModuleSymbol msym, Name flatname) {
457 return compiled.get(Pair.of(msym, flatname));
458 }
459
460 public void removeCompiled(ClassSymbol csym) {
461 compiled.remove(Pair.of(csym.packge().modle, csym.flatname));
462 }
463
464 /* *************************************************************************
465 * Type Checking
466 **************************************************************************/
467
468 /**
469 * A check context is an object that can be used to perform compatibility
470 * checks - depending on the check context, meaning of 'compatibility' might
471 * vary significantly.
472 */
473 public interface CheckContext {
474 /**
475 * Is type 'found' compatible with type 'req' in given context
476 */
477 boolean compatible(Type found, Type req, Warner warn);
478 /**
479 * Report a check error
480 */
481 void report(DiagnosticPosition pos, JCDiagnostic details);
482 /**
483 * Obtain a warner for this check context
484 */
485 public Warner checkWarner(DiagnosticPosition pos, Type found, Type req);
486
487 public InferenceContext inferenceContext();
488
489 public DeferredAttr.DeferredAttrContext deferredAttrContext();
490 }
491
492 /**
493 * This class represent a check context that is nested within another check
494 * context - useful to check sub-expressions. The default behavior simply
495 * redirects all method calls to the enclosing check context leveraging
496 * the forwarding pattern.
497 */
498 static class NestedCheckContext implements CheckContext {
499 CheckContext enclosingContext;
500
501 NestedCheckContext(CheckContext enclosingContext) {
502 this.enclosingContext = enclosingContext;
503 }
504
505 public boolean compatible(Type found, Type req, Warner warn) {
506 return enclosingContext.compatible(found, req, warn);
507 }
508
509 public void report(DiagnosticPosition pos, JCDiagnostic details) {
510 enclosingContext.report(pos, details);
511 }
512
513 public Warner checkWarner(DiagnosticPosition pos, Type found, Type req) {
514 return enclosingContext.checkWarner(pos, found, req);
515 }
516
517 public InferenceContext inferenceContext() {
518 return enclosingContext.inferenceContext();
519 }
520
521 public DeferredAttrContext deferredAttrContext() {
522 return enclosingContext.deferredAttrContext();
523 }
524 }
525
526 /**
527 * Check context to be used when evaluating assignment/return statements
528 */
529 CheckContext basicHandler = new CheckContext() {
530 public void report(DiagnosticPosition pos, JCDiagnostic details) {
531 log.error(pos, "prob.found.req", details);
532 }
533 public boolean compatible(Type found, Type req, Warner warn) {
534 return types.isAssignable(found, req, warn);
535 }
536
537 public Warner checkWarner(DiagnosticPosition pos, Type found, Type req) {
538 return convertWarner(pos, found, req);
539 }
540
541 public InferenceContext inferenceContext() {
542 return infer.emptyContext;
543 }
544
545 public DeferredAttrContext deferredAttrContext() {
546 return deferredAttr.emptyDeferredAttrContext;
547 }
548
549 @Override
550 public String toString() {
551 return "CheckContext: basicHandler";
552 }
553 };
554
555 /** Check that a given type is assignable to a given proto-type.
556 * If it is, return the type, otherwise return errType.
557 * @param pos Position to be used for error reporting.
558 * @param found The type that was found.
559 * @param req The type that was required.
560 */
561 public Type checkType(DiagnosticPosition pos, Type found, Type req) {
562 return checkType(pos, found, req, basicHandler);
563 }
564
565 Type checkType(final DiagnosticPosition pos, final Type found, final Type req, final CheckContext checkContext) {
566 final InferenceContext inferenceContext = checkContext.inferenceContext();
567 if (inferenceContext.free(req) || inferenceContext.free(found)) {
568 inferenceContext.addFreeTypeListener(List.of(req, found), new FreeTypeListener() {
569 @Override
570 public void typesInferred(InferenceContext inferenceContext) {
571 checkType(pos, inferenceContext.asInstType(found), inferenceContext.asInstType(req), checkContext);
572 }
573 });
574 }
575 if (req.hasTag(ERROR))
576 return req;
577 if (req.hasTag(NONE))
578 return found;
579 if (checkContext.compatible(found, req, checkContext.checkWarner(pos, found, req))) {
580 return found;
581 } else {
582 if (found.isNumeric() && req.isNumeric()) {
583 checkContext.report(pos, diags.fragment("possible.loss.of.precision", found, req));
584 return types.createErrorType(found);
585 }
586 checkContext.report(pos, diags.fragment("inconvertible.types", found, req));
587 return types.createErrorType(found);
588 }
589 }
590
591 /** Check that a given type can be cast to a given target type.
592 * Return the result of the cast.
593 * @param pos Position to be used for error reporting.
594 * @param found The type that is being cast.
595 * @param req The target type of the cast.
596 */
597 Type checkCastable(DiagnosticPosition pos, Type found, Type req) {
598 return checkCastable(pos, found, req, basicHandler);
599 }
600 Type checkCastable(DiagnosticPosition pos, Type found, Type req, CheckContext checkContext) {
601 if (types.isCastable(found, req, castWarner(pos, found, req))) {
602 return req;
603 } else {
604 checkContext.report(pos, diags.fragment("inconvertible.types", found, req));
605 return types.createErrorType(found);
606 }
607 }
608
609 /** Check for redundant casts (i.e. where source type is a subtype of target type)
610 * The problem should only be reported for non-292 cast
611 */
612 public void checkRedundantCast(Env<AttrContext> env, final JCTypeCast tree) {
613 if (!tree.type.isErroneous()
614 && types.isSameType(tree.expr.type, tree.clazz.type)
615 && !(ignoreAnnotatedCasts && TreeInfo.containsTypeAnnotation(tree.clazz))
616 && !is292targetTypeCast(tree)) {
617 deferredLintHandler.report(new DeferredLintHandler.LintLogger() {
618 @Override
619 public void report() {
620 if (lint.isEnabled(Lint.LintCategory.CAST))
621 log.warning(Lint.LintCategory.CAST,
622 tree.pos(), "redundant.cast", tree.clazz.type);
623 }
624 });
625 }
626 }
627 //where
628 private boolean is292targetTypeCast(JCTypeCast tree) {
629 boolean is292targetTypeCast = false;
630 JCExpression expr = TreeInfo.skipParens(tree.expr);
631 if (expr.hasTag(APPLY)) {
632 JCMethodInvocation apply = (JCMethodInvocation)expr;
633 Symbol sym = TreeInfo.symbol(apply.meth);
634 is292targetTypeCast = sym != null &&
635 sym.kind == MTH &&
636 (sym.flags() & HYPOTHETICAL) != 0;
637 }
638 return is292targetTypeCast;
639 }
640
641 private static final boolean ignoreAnnotatedCasts = true;
642
643 /** Check that a type is within some bounds.
644 *
645 * Used in TypeApply to verify that, e.g., X in {@code V<X>} is a valid
646 * type argument.
647 * @param a The type that should be bounded by bs.
648 * @param bound The bound.
649 */
650 private boolean checkExtends(Type a, Type bound) {
651 if (a.isUnbound()) {
652 return true;
653 } else if (!a.hasTag(WILDCARD)) {
654 a = types.cvarUpperBound(a);
655 return types.isSubtype(a, bound);
656 } else if (a.isExtendsBound()) {
657 return types.isCastable(bound, types.wildUpperBound(a), types.noWarnings);
658 } else if (a.isSuperBound()) {
659 return !types.notSoftSubtype(types.wildLowerBound(a), bound);
660 }
661 return true;
662 }
663
664 /** Check that type is different from 'void'.
665 * @param pos Position to be used for error reporting.
666 * @param t The type to be checked.
667 */
668 Type checkNonVoid(DiagnosticPosition pos, Type t) {
669 if (t.hasTag(VOID)) {
670 log.error(pos, "void.not.allowed.here");
671 return types.createErrorType(t);
672 } else {
673 return t;
674 }
675 }
676
677 Type checkClassOrArrayType(DiagnosticPosition pos, Type t) {
678 if (!t.hasTag(CLASS) && !t.hasTag(ARRAY) && !t.hasTag(ERROR)) {
679 return typeTagError(pos,
680 diags.fragment("type.req.class.array"),
681 asTypeParam(t));
682 } else {
683 return t;
684 }
685 }
686
687 /** Check that type is a class or interface type.
688 * @param pos Position to be used for error reporting.
689 * @param t The type to be checked.
690 */
691 Type checkClassType(DiagnosticPosition pos, Type t) {
692 if (!t.hasTag(CLASS) && !t.hasTag(ERROR)) {
693 return typeTagError(pos,
694 diags.fragment("type.req.class"),
695 asTypeParam(t));
696 } else {
697 return t;
698 }
699 }
700 //where
701 private Object asTypeParam(Type t) {
702 return (t.hasTag(TYPEVAR))
703 ? diags.fragment("type.parameter", t)
704 : t;
705 }
706
707 /** Check that type is a valid qualifier for a constructor reference expression
708 */
709 Type checkConstructorRefType(DiagnosticPosition pos, Type t) {
710 t = checkClassOrArrayType(pos, t);
711 if (t.hasTag(CLASS)) {
712 if ((t.tsym.flags() & (ABSTRACT | INTERFACE)) != 0) {
713 log.error(pos, "abstract.cant.be.instantiated", t.tsym);
714 t = types.createErrorType(t);
715 } else if ((t.tsym.flags() & ENUM) != 0) {
716 log.error(pos, "enum.cant.be.instantiated");
717 t = types.createErrorType(t);
718 } else {
719 t = checkClassType(pos, t, true);
720 }
721 } else if (t.hasTag(ARRAY)) {
722 if (!types.isReifiable(((ArrayType)t).elemtype)) {
723 log.error(pos, "generic.array.creation");
724 t = types.createErrorType(t);
725 }
726 }
727 return t;
728 }
729
730 /** Check that type is a class or interface type.
731 * @param pos Position to be used for error reporting.
732 * @param t The type to be checked.
733 * @param noBounds True if type bounds are illegal here.
734 */
735 Type checkClassType(DiagnosticPosition pos, Type t, boolean noBounds) {
736 t = checkClassType(pos, t);
737 if (noBounds && t.isParameterized()) {
738 List<Type> args = t.getTypeArguments();
739 while (args.nonEmpty()) {
740 if (args.head.hasTag(WILDCARD))
741 return typeTagError(pos,
742 diags.fragment("type.req.exact"),
743 args.head);
744 args = args.tail;
745 }
746 }
747 return t;
748 }
749
750 /** Check that type is a reference type, i.e. a class, interface or array type
751 * or a type variable.
752 * @param pos Position to be used for error reporting.
753 * @param t The type to be checked.
754 */
755 Type checkRefType(DiagnosticPosition pos, Type t) {
756 if (t.isReference())
757 return t;
758 else
759 return typeTagError(pos,
760 diags.fragment("type.req.ref"),
761 t);
762 }
763
764 /** Check that each type is a reference type, i.e. a class, interface or array type
765 * or a type variable.
766 * @param trees Original trees, used for error reporting.
767 * @param types The types to be checked.
768 */
769 List<Type> checkRefTypes(List<JCExpression> trees, List<Type> types) {
770 List<JCExpression> tl = trees;
771 for (List<Type> l = types; l.nonEmpty(); l = l.tail) {
772 l.head = checkRefType(tl.head.pos(), l.head);
773 tl = tl.tail;
774 }
775 return types;
776 }
777
778 /** Check that type is a null or reference type.
779 * @param pos Position to be used for error reporting.
780 * @param t The type to be checked.
781 */
782 Type checkNullOrRefType(DiagnosticPosition pos, Type t) {
783 if (t.isReference() || t.hasTag(BOT))
784 return t;
785 else
786 return typeTagError(pos,
787 diags.fragment("type.req.ref"),
788 t);
789 }
790
791 /** Check that flag set does not contain elements of two conflicting sets. s
792 * Return true if it doesn't.
793 * @param pos Position to be used for error reporting.
794 * @param flags The set of flags to be checked.
795 * @param set1 Conflicting flags set #1.
796 * @param set2 Conflicting flags set #2.
797 */
798 boolean checkDisjoint(DiagnosticPosition pos, long flags, long set1, long set2) {
799 if ((flags & set1) != 0 && (flags & set2) != 0) {
800 log.error(pos,
801 "illegal.combination.of.modifiers",
802 asFlagSet(TreeInfo.firstFlag(flags & set1)),
803 asFlagSet(TreeInfo.firstFlag(flags & set2)));
804 return false;
805 } else
806 return true;
807 }
808
809 /** Check that usage of diamond operator is correct (i.e. diamond should not
810 * be used with non-generic classes or in anonymous class creation expressions)
811 */
812 Type checkDiamond(JCNewClass tree, Type t) {
813 if (!TreeInfo.isDiamond(tree) ||
814 t.isErroneous()) {
815 return checkClassType(tree.clazz.pos(), t, true);
816 } else {
817 if (tree.def != null && !allowDiamondWithAnonymousClassCreation) {
818 log.error(DiagnosticFlag.SOURCE_LEVEL, tree.clazz.pos(),
819 Errors.CantApplyDiamond1(t, Fragments.DiamondAndAnonClassNotSupportedInSource(source.name)));
820 }
821 if (t.tsym.type.getTypeArguments().isEmpty()) {
822 log.error(tree.clazz.pos(),
823 "cant.apply.diamond.1",
824 t, diags.fragment("diamond.non.generic", t));
825 return types.createErrorType(t);
826 } else if (tree.typeargs != null &&
827 tree.typeargs.nonEmpty()) {
828 log.error(tree.clazz.pos(),
829 "cant.apply.diamond.1",
830 t, diags.fragment("diamond.and.explicit.params", t));
831 return types.createErrorType(t);
832 } else {
833 return t;
834 }
835 }
836 }
837
838 /** Check that the type inferred using the diamond operator does not contain
839 * non-denotable types such as captured types or intersection types.
840 * @param t the type inferred using the diamond operator
841 * @return the (possibly empty) list of non-denotable types.
842 */
843 List<Type> checkDiamondDenotable(ClassType t) {
844 ListBuffer<Type> buf = new ListBuffer<>();
845 for (Type arg : t.allparams()) {
846 if (!diamondTypeChecker.visit(arg, null)) {
847 buf.append(arg);
848 }
849 }
850 return buf.toList();
851 }
852 // where
853
854 /** diamondTypeChecker: A type visitor that descends down the given type looking for non-denotable
855 * types. The visit methods return false as soon as a non-denotable type is encountered and true
856 * otherwise.
857 */
858 private static final Types.SimpleVisitor<Boolean, Void> diamondTypeChecker = new Types.SimpleVisitor<Boolean, Void>() {
859 @Override
860 public Boolean visitType(Type t, Void s) {
861 return true;
862 }
863 @Override
864 public Boolean visitClassType(ClassType t, Void s) {
865 if (t.isCompound()) {
866 return false;
867 }
868 for (Type targ : t.allparams()) {
869 if (!visit(targ, s)) {
870 return false;
871 }
872 }
873 return true;
874 }
875
876 @Override
877 public Boolean visitTypeVar(TypeVar t, Void s) {
878 /* Any type variable mentioned in the inferred type must have been declared as a type parameter
879 (i.e cannot have been produced by inference (18.4))
880 */
881 return t.tsym.owner.type.getTypeArguments().contains(t);
882 }
883
884 @Override
885 public Boolean visitCapturedType(CapturedType t, Void s) {
886 /* Any type variable mentioned in the inferred type must have been declared as a type parameter
887 (i.e cannot have been produced by capture conversion (5.1.10))
888 */
889 return false;
890 }
891
892 @Override
893 public Boolean visitArrayType(ArrayType t, Void s) {
894 return visit(t.elemtype, s);
895 }
896
897 @Override
898 public Boolean visitWildcardType(WildcardType t, Void s) {
899 return visit(t.type, s);
900 }
901 };
902
903 void checkVarargsMethodDecl(Env<AttrContext> env, JCMethodDecl tree) {
904 MethodSymbol m = tree.sym;
905 if (!allowSimplifiedVarargs) return;
906 boolean hasTrustMeAnno = m.attribute(syms.trustMeType.tsym) != null;
907 Type varargElemType = null;
908 if (m.isVarArgs()) {
909 varargElemType = types.elemtype(tree.params.last().type);
910 }
911 if (hasTrustMeAnno && !isTrustMeAllowedOnMethod(m)) {
912 if (varargElemType != null) {
913 log.error(tree,
914 "varargs.invalid.trustme.anno",
915 syms.trustMeType.tsym,
916 allowPrivateSafeVarargs ?
917 diags.fragment("varargs.trustme.on.virtual.varargs", m) :
918 diags.fragment("varargs.trustme.on.virtual.varargs.final.only", m));
919 } else {
920 log.error(tree,
921 "varargs.invalid.trustme.anno",
922 syms.trustMeType.tsym,
923 diags.fragment("varargs.trustme.on.non.varargs.meth", m));
924 }
925 } else if (hasTrustMeAnno && varargElemType != null &&
926 types.isReifiable(varargElemType)) {
927 warnUnsafeVararg(tree,
928 "varargs.redundant.trustme.anno",
929 syms.trustMeType.tsym,
930 diags.fragment("varargs.trustme.on.reifiable.varargs", varargElemType));
931 }
932 else if (!hasTrustMeAnno && varargElemType != null &&
933 !types.isReifiable(varargElemType)) {
934 warnUnchecked(tree.params.head.pos(), "unchecked.varargs.non.reifiable.type", varargElemType);
935 }
936 }
937 //where
938 private boolean isTrustMeAllowedOnMethod(Symbol s) {
939 return (s.flags() & VARARGS) != 0 &&
940 (s.isConstructor() ||
941 (s.flags() & (STATIC | FINAL |
942 (allowPrivateSafeVarargs ? PRIVATE : 0) )) != 0);
943 }
944
945 Type checkMethod(final Type mtype,
946 final Symbol sym,
947 final Env<AttrContext> env,
948 final List<JCExpression> argtrees,
949 final List<Type> argtypes,
950 final boolean useVarargs,
951 InferenceContext inferenceContext) {
952 // System.out.println("call : " + env.tree);
953 // System.out.println("method : " + owntype);
954 // System.out.println("actuals: " + argtypes);
955 if (inferenceContext.free(mtype)) {
956 inferenceContext.addFreeTypeListener(List.of(mtype), new FreeTypeListener() {
957 public void typesInferred(InferenceContext inferenceContext) {
958 checkMethod(inferenceContext.asInstType(mtype), sym, env, argtrees, argtypes, useVarargs, inferenceContext);
959 }
960 });
961 return mtype;
962 }
963 Type owntype = mtype;
964 List<Type> formals = owntype.getParameterTypes();
965 List<Type> nonInferred = sym.type.getParameterTypes();
966 if (nonInferred.length() != formals.length()) nonInferred = formals;
967 Type last = useVarargs ? formals.last() : null;
968 if (sym.name == names.init && sym.owner == syms.enumSym) {
969 formals = formals.tail.tail;
970 nonInferred = nonInferred.tail.tail;
971 }
972 List<JCExpression> args = argtrees;
973 if (args != null) {
974 //this is null when type-checking a method reference
975 while (formals.head != last) {
976 JCTree arg = args.head;
977 Warner warn = convertWarner(arg.pos(), arg.type, nonInferred.head);
978 assertConvertible(arg, arg.type, formals.head, warn);
979 args = args.tail;
980 formals = formals.tail;
981 nonInferred = nonInferred.tail;
982 }
983 if (useVarargs) {
984 Type varArg = types.elemtype(last);
985 while (args.tail != null) {
986 JCTree arg = args.head;
987 Warner warn = convertWarner(arg.pos(), arg.type, varArg);
988 assertConvertible(arg, arg.type, varArg, warn);
989 args = args.tail;
990 }
991 } else if ((sym.flags() & (VARARGS | SIGNATURE_POLYMORPHIC)) == VARARGS) {
992 // non-varargs call to varargs method
993 Type varParam = owntype.getParameterTypes().last();
994 Type lastArg = argtypes.last();
995 if (types.isSubtypeUnchecked(lastArg, types.elemtype(varParam)) &&
996 !types.isSameType(types.erasure(varParam), types.erasure(lastArg)))
997 log.warning(argtrees.last().pos(), "inexact.non-varargs.call",
998 types.elemtype(varParam), varParam);
999 }
1000 }
1001 if (useVarargs) {
1002 Type argtype = owntype.getParameterTypes().last();
1003 if (!types.isReifiable(argtype) &&
1004 (!allowSimplifiedVarargs ||
1005 sym.baseSymbol().attribute(syms.trustMeType.tsym) == null ||
1006 !isTrustMeAllowedOnMethod(sym))) {
1007 warnUnchecked(env.tree.pos(),
1008 "unchecked.generic.array.creation",
1009 argtype);
1010 }
1011 if ((sym.baseSymbol().flags() & SIGNATURE_POLYMORPHIC) == 0) {
1012 TreeInfo.setVarargsElement(env.tree, types.elemtype(argtype));
1013 }
1014 }
1015 return owntype;
1016 }
1017 //where
1018 private void assertConvertible(JCTree tree, Type actual, Type formal, Warner warn) {
1019 if (types.isConvertible(actual, formal, warn))
1020 return;
1021
1022 if (formal.isCompound()
1023 && types.isSubtype(actual, types.supertype(formal))
1024 && types.isSubtypeUnchecked(actual, types.interfaces(formal), warn))
1025 return;
1026 }
1027
1028 /**
1029 * Check that type 't' is a valid instantiation of a generic class
1030 * (see JLS 4.5)
1031 *
1032 * @param t class type to be checked
1033 * @return true if 't' is well-formed
1034 */
1035 public boolean checkValidGenericType(Type t) {
1036 return firstIncompatibleTypeArg(t) == null;
1037 }
1038 //WHERE
1039 private Type firstIncompatibleTypeArg(Type type) {
1040 List<Type> formals = type.tsym.type.allparams();
1041 List<Type> actuals = type.allparams();
1042 List<Type> args = type.getTypeArguments();
1043 List<Type> forms = type.tsym.type.getTypeArguments();
1044 ListBuffer<Type> bounds_buf = new ListBuffer<>();
1045
1046 // For matching pairs of actual argument types `a' and
1047 // formal type parameters with declared bound `b' ...
1048 while (args.nonEmpty() && forms.nonEmpty()) {
1049 // exact type arguments needs to know their
1050 // bounds (for upper and lower bound
1051 // calculations). So we create new bounds where
1052 // type-parameters are replaced with actuals argument types.
1053 bounds_buf.append(types.subst(forms.head.getUpperBound(), formals, actuals));
1054 args = args.tail;
1055 forms = forms.tail;
1056 }
1057
1058 args = type.getTypeArguments();
1059 List<Type> tvars_cap = types.substBounds(formals,
1060 formals,
1061 types.capture(type).allparams());
1062 while (args.nonEmpty() && tvars_cap.nonEmpty()) {
1063 // Let the actual arguments know their bound
1064 args.head.withTypeVar((TypeVar)tvars_cap.head);
1065 args = args.tail;
1066 tvars_cap = tvars_cap.tail;
1067 }
1068
1069 args = type.getTypeArguments();
1070 List<Type> bounds = bounds_buf.toList();
1071
1072 while (args.nonEmpty() && bounds.nonEmpty()) {
1073 Type actual = args.head;
1074 if (!isTypeArgErroneous(actual) &&
1075 !bounds.head.isErroneous() &&
1076 !checkExtends(actual, bounds.head)) {
1077 return args.head;
1078 }
1079 args = args.tail;
1080 bounds = bounds.tail;
1081 }
1082
1083 args = type.getTypeArguments();
1084 bounds = bounds_buf.toList();
1085
1086 for (Type arg : types.capture(type).getTypeArguments()) {
1087 if (arg.hasTag(TYPEVAR) &&
1088 arg.getUpperBound().isErroneous() &&
1089 !bounds.head.isErroneous() &&
1090 !isTypeArgErroneous(args.head)) {
1091 return args.head;
1092 }
1093 bounds = bounds.tail;
1094 args = args.tail;
1095 }
1096
1097 return null;
1098 }
1099 //where
1100 boolean isTypeArgErroneous(Type t) {
1101 return isTypeArgErroneous.visit(t);
1102 }
1103
1104 Types.UnaryVisitor<Boolean> isTypeArgErroneous = new Types.UnaryVisitor<Boolean>() {
1105 public Boolean visitType(Type t, Void s) {
1106 return t.isErroneous();
1107 }
1108 @Override
1109 public Boolean visitTypeVar(TypeVar t, Void s) {
1110 return visit(t.getUpperBound());
1111 }
1112 @Override
1113 public Boolean visitCapturedType(CapturedType t, Void s) {
1114 return visit(t.getUpperBound()) ||
1115 visit(t.getLowerBound());
1116 }
1117 @Override
1118 public Boolean visitWildcardType(WildcardType t, Void s) {
1119 return visit(t.type);
1120 }
1121 };
1122
1123 /** Check that given modifiers are legal for given symbol and
1124 * return modifiers together with any implicit modifiers for that symbol.
1125 * Warning: we can't use flags() here since this method
1126 * is called during class enter, when flags() would cause a premature
1127 * completion.
1128 * @param pos Position to be used for error reporting.
1129 * @param flags The set of modifiers given in a definition.
1130 * @param sym The defined symbol.
1131 */
1132 long checkFlags(DiagnosticPosition pos, long flags, Symbol sym, JCTree tree) {
1133 long mask;
1134 long implicit = 0;
1135
1136 switch (sym.kind) {
1137 case VAR:
1138 if (TreeInfo.isReceiverParam(tree))
1139 mask = ReceiverParamFlags;
1140 else if (sym.owner.kind != TYP)
1141 mask = LocalVarFlags;
1142 else if ((sym.owner.flags_field & INTERFACE) != 0)
1143 mask = implicit = InterfaceVarFlags;
1144 else
1145 mask = VarFlags;
1146 break;
1147 case MTH:
1148 if (sym.name == names.init) {
1149 if ((sym.owner.flags_field & ENUM) != 0) {
1150 // enum constructors cannot be declared public or
1151 // protected and must be implicitly or explicitly
1152 // private
1153 implicit = PRIVATE;
1154 mask = PRIVATE;
1155 } else
1156 mask = ConstructorFlags;
1157 } else if ((sym.owner.flags_field & INTERFACE) != 0) {
1158 if ((sym.owner.flags_field & ANNOTATION) != 0) {
1159 mask = AnnotationTypeElementMask;
1160 implicit = PUBLIC | ABSTRACT;
1161 } else if ((flags & (DEFAULT | STATIC | PRIVATE)) != 0) {
1162 mask = InterfaceMethodMask;
1163 implicit = (flags & PRIVATE) != 0 ? 0 : PUBLIC;
1164 if ((flags & DEFAULT) != 0) {
1165 implicit |= ABSTRACT;
1166 }
1167 } else {
1168 mask = implicit = InterfaceMethodFlags;
1169 }
1170 } else {
1171 mask = MethodFlags;
1172 }
1173 // Imply STRICTFP if owner has STRICTFP set.
1174 if (((flags|implicit) & Flags.ABSTRACT) == 0 ||
1175 ((flags) & Flags.DEFAULT) != 0)
1176 implicit |= sym.owner.flags_field & STRICTFP;
1177 break;
1178 case TYP:
1179 if (sym.isLocal()) {
1180 mask = LocalClassFlags;
1181 if ((sym.owner.flags_field & STATIC) == 0 &&
1182 (flags & ENUM) != 0)
1183 log.error(pos, "enums.must.be.static");
1184 } else if (sym.owner.kind == TYP) {
1185 mask = MemberClassFlags;
1186 if (sym.owner.owner.kind == PCK ||
1187 (sym.owner.flags_field & STATIC) != 0)
1188 mask |= STATIC;
1189 else if ((flags & ENUM) != 0)
1190 log.error(pos, "enums.must.be.static");
1191 // Nested interfaces and enums are always STATIC (Spec ???)
1192 if ((flags & (INTERFACE | ENUM)) != 0 ) implicit = STATIC;
1193 } else {
1194 mask = ClassFlags;
1195 }
1196 // Interfaces are always ABSTRACT
1197 if ((flags & INTERFACE) != 0) implicit |= ABSTRACT;
1198
1199 if ((flags & ENUM) != 0) {
1200 // enums can't be declared abstract or final
1201 mask &= ~(ABSTRACT | FINAL);
1202 implicit |= implicitEnumFinalFlag(tree);
1203 }
1204 // Imply STRICTFP if owner has STRICTFP set.
1205 implicit |= sym.owner.flags_field & STRICTFP;
1206 break;
1207 default:
1208 throw new AssertionError();
1209 }
1210 long illegal = flags & ExtendedStandardFlags & ~mask;
1211 if (illegal != 0) {
1212 if ((illegal & INTERFACE) != 0) {
1213 log.error(pos, "intf.not.allowed.here");
1214 mask |= INTERFACE;
1215 }
1216 else {
1217 log.error(pos,
1218 "mod.not.allowed.here", asFlagSet(illegal));
1219 }
1220 }
1221 else if ((sym.kind == TYP ||
1222 // ISSUE: Disallowing abstract&private is no longer appropriate
1223 // in the presence of inner classes. Should it be deleted here?
1224 checkDisjoint(pos, flags,
1225 ABSTRACT,
1226 PRIVATE | STATIC | DEFAULT))
1227 &&
1228 checkDisjoint(pos, flags,
1229 STATIC | PRIVATE,
1230 DEFAULT)
1231 &&
1232 checkDisjoint(pos, flags,
1233 ABSTRACT | INTERFACE,
1234 FINAL | NATIVE | SYNCHRONIZED)
1235 &&
1236 checkDisjoint(pos, flags,
1237 PUBLIC,
1238 PRIVATE | PROTECTED)
1239 &&
1240 checkDisjoint(pos, flags,
1241 PRIVATE,
1242 PUBLIC | PROTECTED)
1243 &&
1244 checkDisjoint(pos, flags,
1245 FINAL,
1246 VOLATILE)
1247 &&
1248 (sym.kind == TYP ||
1249 checkDisjoint(pos, flags,
1250 ABSTRACT | NATIVE,
1251 STRICTFP))) {
1252 // skip
1253 }
1254 return flags & (mask | ~ExtendedStandardFlags) | implicit;
1255 }
1256
1257
1258 /** Determine if this enum should be implicitly final.
1259 *
1260 * If the enum has no specialized enum contants, it is final.
1261 *
1262 * If the enum does have specialized enum contants, it is
1263 * <i>not</i> final.
1264 */
1265 private long implicitEnumFinalFlag(JCTree tree) {
1266 if (!tree.hasTag(CLASSDEF)) return 0;
1267 class SpecialTreeVisitor extends JCTree.Visitor {
1268 boolean specialized;
1269 SpecialTreeVisitor() {
1270 this.specialized = false;
1271 }
1272
1273 @Override
1274 public void visitTree(JCTree tree) { /* no-op */ }
1275
1276 @Override
1277 public void visitVarDef(JCVariableDecl tree) {
1278 if ((tree.mods.flags & ENUM) != 0) {
1279 if (tree.init instanceof JCNewClass &&
1280 ((JCNewClass) tree.init).def != null) {
1281 specialized = true;
1282 }
1283 }
1284 }
1285 }
1286
1287 SpecialTreeVisitor sts = new SpecialTreeVisitor();
1288 JCClassDecl cdef = (JCClassDecl) tree;
1289 for (JCTree defs: cdef.defs) {
1290 defs.accept(sts);
1291 if (sts.specialized) return 0;
1292 }
1293 return FINAL;
1294 }
1295
1296 /* *************************************************************************
1297 * Type Validation
1298 **************************************************************************/
1299
1300 /** Validate a type expression. That is,
1301 * check that all type arguments of a parametric type are within
1302 * their bounds. This must be done in a second phase after type attribution
1303 * since a class might have a subclass as type parameter bound. E.g:
1304 *
1305 * <pre>{@code
1306 * class B<A extends C> { ... }
1307 * class C extends B<C> { ... }
1308 * }</pre>
1309 *
1310 * and we can't make sure that the bound is already attributed because
1311 * of possible cycles.
1312 *
1313 * Visitor method: Validate a type expression, if it is not null, catching
1314 * and reporting any completion failures.
1315 */
1316 void validate(JCTree tree, Env<AttrContext> env) {
1317 validate(tree, env, true);
1318 }
1319 void validate(JCTree tree, Env<AttrContext> env, boolean checkRaw) {
1320 new Validator(env).validateTree(tree, checkRaw, true);
1321 }
1322
1323 /** Visitor method: Validate a list of type expressions.
1324 */
1325 void validate(List<? extends JCTree> trees, Env<AttrContext> env) {
1326 for (List<? extends JCTree> l = trees; l.nonEmpty(); l = l.tail)
1327 validate(l.head, env);
1328 }
1329
1330 /** A visitor class for type validation.
1331 */
1332 class Validator extends JCTree.Visitor {
1333
1334 boolean checkRaw;
1335 boolean isOuter;
1336 Env<AttrContext> env;
1337
1338 Validator(Env<AttrContext> env) {
1339 this.env = env;
1340 }
1341
1342 @Override
1343 public void visitTypeArray(JCArrayTypeTree tree) {
1344 validateTree(tree.elemtype, checkRaw, isOuter);
1345 }
1346
1347 @Override
1348 public void visitTypeApply(JCTypeApply tree) {
1349 if (tree.type.hasTag(CLASS)) {
1350 List<JCExpression> args = tree.arguments;
1351 List<Type> forms = tree.type.tsym.type.getTypeArguments();
1352
1353 Type incompatibleArg = firstIncompatibleTypeArg(tree.type);
1354 if (incompatibleArg != null) {
1355 for (JCTree arg : tree.arguments) {
1356 if (arg.type == incompatibleArg) {
1357 log.error(arg, "not.within.bounds", incompatibleArg, forms.head);
1358 }
1359 forms = forms.tail;
1360 }
1361 }
1362
1363 forms = tree.type.tsym.type.getTypeArguments();
1364
1365 boolean is_java_lang_Class = tree.type.tsym.flatName() == names.java_lang_Class;
1366
1367 // For matching pairs of actual argument types `a' and
1368 // formal type parameters with declared bound `b' ...
1369 while (args.nonEmpty() && forms.nonEmpty()) {
1370 validateTree(args.head,
1371 !(isOuter && is_java_lang_Class),
1372 false);
1373 args = args.tail;
1374 forms = forms.tail;
1375 }
1376
1377 // Check that this type is either fully parameterized, or
1378 // not parameterized at all.
1379 if (tree.type.getEnclosingType().isRaw())
1380 log.error(tree.pos(), "improperly.formed.type.inner.raw.param");
1381 if (tree.clazz.hasTag(SELECT))
1382 visitSelectInternal((JCFieldAccess)tree.clazz);
1383 }
1384 }
1385
1386 @Override
1387 public void visitTypeParameter(JCTypeParameter tree) {
1388 validateTrees(tree.bounds, true, isOuter);
1389 checkClassBounds(tree.pos(), tree.type);
1390 }
1391
1392 @Override
1393 public void visitWildcard(JCWildcard tree) {
1394 if (tree.inner != null)
1395 validateTree(tree.inner, true, isOuter);
1396 }
1397
1398 @Override
1399 public void visitSelect(JCFieldAccess tree) {
1400 if (tree.type.hasTag(CLASS)) {
1401 visitSelectInternal(tree);
1402
1403 // Check that this type is either fully parameterized, or
1404 // not parameterized at all.
1405 if (tree.selected.type.isParameterized() && tree.type.tsym.type.getTypeArguments().nonEmpty())
1406 log.error(tree.pos(), "improperly.formed.type.param.missing");
1407 }
1408 }
1409
1410 public void visitSelectInternal(JCFieldAccess tree) {
1411 if (tree.type.tsym.isStatic() &&
1412 tree.selected.type.isParameterized()) {
1413 // The enclosing type is not a class, so we are
1414 // looking at a static member type. However, the
1415 // qualifying expression is parameterized.
1416 log.error(tree.pos(), "cant.select.static.class.from.param.type");
1417 } else {
1418 // otherwise validate the rest of the expression
1419 tree.selected.accept(this);
1420 }
1421 }
1422
1423 @Override
1424 public void visitAnnotatedType(JCAnnotatedType tree) {
1425 tree.underlyingType.accept(this);
1426 }
1427
1428 @Override
1429 public void visitTypeIdent(JCPrimitiveTypeTree that) {
1430 if (that.type.hasTag(TypeTag.VOID)) {
1431 log.error(that.pos(), "void.not.allowed.here");
1432 }
1433 super.visitTypeIdent(that);
1434 }
1435
1436 /** Default visitor method: do nothing.
1437 */
1438 @Override
1439 public void visitTree(JCTree tree) {
1440 }
1441
1442 public void validateTree(JCTree tree, boolean checkRaw, boolean isOuter) {
1443 if (tree != null) {
1444 boolean prevCheckRaw = this.checkRaw;
1445 this.checkRaw = checkRaw;
1446 this.isOuter = isOuter;
1447
1448 try {
1449 tree.accept(this);
1450 if (checkRaw)
1451 checkRaw(tree, env);
1452 } catch (CompletionFailure ex) {
1453 completionError(tree.pos(), ex);
1454 } finally {
1455 this.checkRaw = prevCheckRaw;
1456 }
1457 }
1458 }
1459
1460 public void validateTrees(List<? extends JCTree> trees, boolean checkRaw, boolean isOuter) {
1461 for (List<? extends JCTree> l = trees; l.nonEmpty(); l = l.tail)
1462 validateTree(l.head, checkRaw, isOuter);
1463 }
1464 }
1465
1466 void checkRaw(JCTree tree, Env<AttrContext> env) {
1467 if (lint.isEnabled(LintCategory.RAW) &&
1468 tree.type.hasTag(CLASS) &&
1469 !TreeInfo.isDiamond(tree) &&
1470 !withinAnonConstr(env) &&
1471 tree.type.isRaw()) {
1472 log.warning(LintCategory.RAW,
1473 tree.pos(), "raw.class.use", tree.type, tree.type.tsym.type);
1474 }
1475 }
1476 //where
1477 private boolean withinAnonConstr(Env<AttrContext> env) {
1478 return env.enclClass.name.isEmpty() &&
1479 env.enclMethod != null && env.enclMethod.name == names.init;
1480 }
1481
1482 /* *************************************************************************
1483 * Exception checking
1484 **************************************************************************/
1485
1486 /* The following methods treat classes as sets that contain
1487 * the class itself and all their subclasses
1488 */
1489
1490 /** Is given type a subtype of some of the types in given list?
1491 */
1492 boolean subset(Type t, List<Type> ts) {
1493 for (List<Type> l = ts; l.nonEmpty(); l = l.tail)
1494 if (types.isSubtype(t, l.head)) return true;
1495 return false;
1496 }
1497
1498 /** Is given type a subtype or supertype of
1499 * some of the types in given list?
1500 */
1501 boolean intersects(Type t, List<Type> ts) {
1502 for (List<Type> l = ts; l.nonEmpty(); l = l.tail)
1503 if (types.isSubtype(t, l.head) || types.isSubtype(l.head, t)) return true;
1504 return false;
1505 }
1506
1507 /** Add type set to given type list, unless it is a subclass of some class
1508 * in the list.
1509 */
1510 List<Type> incl(Type t, List<Type> ts) {
1511 return subset(t, ts) ? ts : excl(t, ts).prepend(t);
1512 }
1513
1514 /** Remove type set from type set list.
1515 */
1516 List<Type> excl(Type t, List<Type> ts) {
1517 if (ts.isEmpty()) {
1518 return ts;
1519 } else {
1520 List<Type> ts1 = excl(t, ts.tail);
1521 if (types.isSubtype(ts.head, t)) return ts1;
1522 else if (ts1 == ts.tail) return ts;
1523 else return ts1.prepend(ts.head);
1524 }
1525 }
1526
1527 /** Form the union of two type set lists.
1528 */
1529 List<Type> union(List<Type> ts1, List<Type> ts2) {
1530 List<Type> ts = ts1;
1531 for (List<Type> l = ts2; l.nonEmpty(); l = l.tail)
1532 ts = incl(l.head, ts);
1533 return ts;
1534 }
1535
1536 /** Form the difference of two type lists.
1537 */
1538 List<Type> diff(List<Type> ts1, List<Type> ts2) {
1539 List<Type> ts = ts1;
1540 for (List<Type> l = ts2; l.nonEmpty(); l = l.tail)
1541 ts = excl(l.head, ts);
1542 return ts;
1543 }
1544
1545 /** Form the intersection of two type lists.
1546 */
1547 public List<Type> intersect(List<Type> ts1, List<Type> ts2) {
1548 List<Type> ts = List.nil();
1549 for (List<Type> l = ts1; l.nonEmpty(); l = l.tail)
1550 if (subset(l.head, ts2)) ts = incl(l.head, ts);
1551 for (List<Type> l = ts2; l.nonEmpty(); l = l.tail)
1552 if (subset(l.head, ts1)) ts = incl(l.head, ts);
1553 return ts;
1554 }
1555
1556 /** Is exc an exception symbol that need not be declared?
1557 */
1558 boolean isUnchecked(ClassSymbol exc) {
1559 return
1560 exc.kind == ERR ||
1561 exc.isSubClass(syms.errorType.tsym, types) ||
1562 exc.isSubClass(syms.runtimeExceptionType.tsym, types);
1563 }
1564
1565 /** Is exc an exception type that need not be declared?
1566 */
1567 boolean isUnchecked(Type exc) {
1568 return
1569 (exc.hasTag(TYPEVAR)) ? isUnchecked(types.supertype(exc)) :
1570 (exc.hasTag(CLASS)) ? isUnchecked((ClassSymbol)exc.tsym) :
1571 exc.hasTag(BOT);
1572 }
1573
1574 /** Same, but handling completion failures.
1575 */
1576 boolean isUnchecked(DiagnosticPosition pos, Type exc) {
1577 try {
1578 return isUnchecked(exc);
1579 } catch (CompletionFailure ex) {
1580 completionError(pos, ex);
1581 return true;
1582 }
1583 }
1584
1585 /** Is exc handled by given exception list?
1586 */
1587 boolean isHandled(Type exc, List<Type> handled) {
1588 return isUnchecked(exc) || subset(exc, handled);
1589 }
1590
1591 /** Return all exceptions in thrown list that are not in handled list.
1592 * @param thrown The list of thrown exceptions.
1593 * @param handled The list of handled exceptions.
1594 */
1595 List<Type> unhandled(List<Type> thrown, List<Type> handled) {
1596 List<Type> unhandled = List.nil();
1597 for (List<Type> l = thrown; l.nonEmpty(); l = l.tail)
1598 if (!isHandled(l.head, handled)) unhandled = unhandled.prepend(l.head);
1599 return unhandled;
1600 }
1601
1602 /* *************************************************************************
1603 * Overriding/Implementation checking
1604 **************************************************************************/
1605
1606 /** The level of access protection given by a flag set,
1607 * where PRIVATE is highest and PUBLIC is lowest.
1608 */
1609 static int protection(long flags) {
1610 switch ((short)(flags & AccessFlags)) {
1611 case PRIVATE: return 3;
1612 case PROTECTED: return 1;
1613 default:
1614 case PUBLIC: return 0;
1615 case 0: return 2;
1616 }
1617 }
1618
1619 /** A customized "cannot override" error message.
1620 * @param m The overriding method.
1621 * @param other The overridden method.
1622 * @return An internationalized string.
1623 */
1624 Object cannotOverride(MethodSymbol m, MethodSymbol other) {
1625 String key;
1626 if ((other.owner.flags() & INTERFACE) == 0)
1627 key = "cant.override";
1628 else if ((m.owner.flags() & INTERFACE) == 0)
1629 key = "cant.implement";
1630 else
1631 key = "clashes.with";
1632 return diags.fragment(key, m, m.location(), other, other.location());
1633 }
1634
1635 /** A customized "override" warning message.
1636 * @param m The overriding method.
1637 * @param other The overridden method.
1638 * @return An internationalized string.
1639 */
1640 Object uncheckedOverrides(MethodSymbol m, MethodSymbol other) {
1641 String key;
1642 if ((other.owner.flags() & INTERFACE) == 0)
1643 key = "unchecked.override";
1644 else if ((m.owner.flags() & INTERFACE) == 0)
1645 key = "unchecked.implement";
1646 else
1647 key = "unchecked.clash.with";
1648 return diags.fragment(key, m, m.location(), other, other.location());
1649 }
1650
1651 /** A customized "override" warning message.
1652 * @param m The overriding method.
1653 * @param other The overridden method.
1654 * @return An internationalized string.
1655 */
1656 Object varargsOverrides(MethodSymbol m, MethodSymbol other) {
1657 String key;
1658 if ((other.owner.flags() & INTERFACE) == 0)
1659 key = "varargs.override";
1660 else if ((m.owner.flags() & INTERFACE) == 0)
1661 key = "varargs.implement";
1662 else
1663 key = "varargs.clash.with";
1664 return diags.fragment(key, m, m.location(), other, other.location());
1665 }
1666
1667 /** Check that this method conforms with overridden method 'other'.
1668 * where `origin' is the class where checking started.
1669 * Complications:
1670 * (1) Do not check overriding of synthetic methods
1671 * (reason: they might be final).
1672 * todo: check whether this is still necessary.
1673 * (2) Admit the case where an interface proxy throws fewer exceptions
1674 * than the method it implements. Augment the proxy methods with the
1675 * undeclared exceptions in this case.
1676 * (3) When generics are enabled, admit the case where an interface proxy
1677 * has a result type
1678 * extended by the result type of the method it implements.
1679 * Change the proxies result type to the smaller type in this case.
1680 *
1681 * @param tree The tree from which positions
1682 * are extracted for errors.
1683 * @param m The overriding method.
1684 * @param other The overridden method.
1685 * @param origin The class of which the overriding method
1686 * is a member.
1687 */
1688 void checkOverride(JCTree tree,
1689 MethodSymbol m,
1690 MethodSymbol other,
1691 ClassSymbol origin) {
1692 // Don't check overriding of synthetic methods or by bridge methods.
1693 if ((m.flags() & (SYNTHETIC|BRIDGE)) != 0 || (other.flags() & SYNTHETIC) != 0) {
1694 return;
1695 }
1696
1697 // Error if static method overrides instance method (JLS 8.4.6.2).
1698 if ((m.flags() & STATIC) != 0 &&
1699 (other.flags() & STATIC) == 0) {
1700 log.error(TreeInfo.diagnosticPositionFor(m, tree), "override.static",
1701 cannotOverride(m, other));
1702 m.flags_field |= BAD_OVERRIDE;
1703 return;
1704 }
1705
1706 // Error if instance method overrides static or final
1707 // method (JLS 8.4.6.1).
1708 if ((other.flags() & FINAL) != 0 ||
1709 (m.flags() & STATIC) == 0 &&
1710 (other.flags() & STATIC) != 0) {
1711 log.error(TreeInfo.diagnosticPositionFor(m, tree), "override.meth",
1712 cannotOverride(m, other),
1713 asFlagSet(other.flags() & (FINAL | STATIC)));
1714 m.flags_field |= BAD_OVERRIDE;
1715 return;
1716 }
1717
1718 if ((m.owner.flags() & ANNOTATION) != 0) {
1719 // handled in validateAnnotationMethod
1720 return;
1721 }
1722
1723 // Error if overriding method has weaker access (JLS 8.4.6.3).
1724 if (protection(m.flags()) > protection(other.flags())) {
1725 log.error(TreeInfo.diagnosticPositionFor(m, tree), "override.weaker.access",
1726 cannotOverride(m, other),
1727 (other.flags() & AccessFlags) == 0 ?
1728 "package" :
1729 asFlagSet(other.flags() & AccessFlags));
1730 m.flags_field |= BAD_OVERRIDE;
1731 return;
1732 }
1733
1734 Type mt = types.memberType(origin.type, m);
1735 Type ot = types.memberType(origin.type, other);
1736 // Error if overriding result type is different
1737 // (or, in the case of generics mode, not a subtype) of
1738 // overridden result type. We have to rename any type parameters
1739 // before comparing types.
1740 List<Type> mtvars = mt.getTypeArguments();
1741 List<Type> otvars = ot.getTypeArguments();
1742 Type mtres = mt.getReturnType();
1743 Type otres = types.subst(ot.getReturnType(), otvars, mtvars);
1744
1745 overrideWarner.clear();
1746 boolean resultTypesOK =
1747 types.returnTypeSubstitutable(mt, ot, otres, overrideWarner);
1748 if (!resultTypesOK) {
1749 if ((m.flags() & STATIC) != 0 && (other.flags() & STATIC) != 0) {
1750 log.error(TreeInfo.diagnosticPositionFor(m, tree),
1751 Errors.OverrideIncompatibleRet(Fragments.CantHide(m, m.location(), other,
1752 other.location()), mtres, otres));
1753 m.flags_field |= BAD_OVERRIDE;
1754 } else {
1755 log.error(TreeInfo.diagnosticPositionFor(m, tree),
1756 "override.incompatible.ret",
1757 cannotOverride(m, other),
1758 mtres, otres);
1759 m.flags_field |= BAD_OVERRIDE;
1760 }
1761 return;
1762 } else if (overrideWarner.hasNonSilentLint(LintCategory.UNCHECKED)) {
1763 warnUnchecked(TreeInfo.diagnosticPositionFor(m, tree),
1764 "override.unchecked.ret",
1765 uncheckedOverrides(m, other),
1766 mtres, otres);
1767 }
1768
1769 // Error if overriding method throws an exception not reported
1770 // by overridden method.
1771 List<Type> otthrown = types.subst(ot.getThrownTypes(), otvars, mtvars);
1772 List<Type> unhandledErased = unhandled(mt.getThrownTypes(), types.erasure(otthrown));
1773 List<Type> unhandledUnerased = unhandled(mt.getThrownTypes(), otthrown);
1774 if (unhandledErased.nonEmpty()) {
1775 log.error(TreeInfo.diagnosticPositionFor(m, tree),
1776 "override.meth.doesnt.throw",
1777 cannotOverride(m, other),
1778 unhandledUnerased.head);
1779 m.flags_field |= BAD_OVERRIDE;
1780 return;
1781 }
1782 else if (unhandledUnerased.nonEmpty()) {
1783 warnUnchecked(TreeInfo.diagnosticPositionFor(m, tree),
1784 "override.unchecked.thrown",
1785 cannotOverride(m, other),
1786 unhandledUnerased.head);
1787 return;
1788 }
1789
1790 // Optional warning if varargs don't agree
1791 if ((((m.flags() ^ other.flags()) & Flags.VARARGS) != 0)
1792 && lint.isEnabled(LintCategory.OVERRIDES)) {
1793 log.warning(TreeInfo.diagnosticPositionFor(m, tree),
1794 ((m.flags() & Flags.VARARGS) != 0)
1795 ? "override.varargs.missing"
1796 : "override.varargs.extra",
1797 varargsOverrides(m, other));
1798 }
1799
1800 // Warn if instance method overrides bridge method (compiler spec ??)
1801 if ((other.flags() & BRIDGE) != 0) {
1802 log.warning(TreeInfo.diagnosticPositionFor(m, tree), "override.bridge",
1803 uncheckedOverrides(m, other));
1804 }
1805
1806 // Warn if a deprecated method overridden by a non-deprecated one.
1807 if (!isDeprecatedOverrideIgnorable(other, origin)) {
1808 Lint prevLint = setLint(lint.augment(m));
1809 try {
1810 checkDeprecated(TreeInfo.diagnosticPositionFor(m, tree), m, other);
1811 } finally {
1812 setLint(prevLint);
1813 }
1814 }
1815 }
1816 // where
1817 private boolean isDeprecatedOverrideIgnorable(MethodSymbol m, ClassSymbol origin) {
1818 // If the method, m, is defined in an interface, then ignore the issue if the method
1819 // is only inherited via a supertype and also implemented in the supertype,
1820 // because in that case, we will rediscover the issue when examining the method
1821 // in the supertype.
1822 // If the method, m, is not defined in an interface, then the only time we need to
1823 // address the issue is when the method is the supertype implemementation: any other
1824 // case, we will have dealt with when examining the supertype classes
1825 ClassSymbol mc = m.enclClass();
1826 Type st = types.supertype(origin.type);
1827 if (!st.hasTag(CLASS))
1828 return true;
1829 MethodSymbol stimpl = m.implementation((ClassSymbol)st.tsym, types, false);
1830
1831 if (mc != null && ((mc.flags() & INTERFACE) != 0)) {
1832 List<Type> intfs = types.interfaces(origin.type);
1833 return (intfs.contains(mc.type) ? false : (stimpl != null));
1834 }
1835 else
1836 return (stimpl != m);
1837 }
1838
1839
1840 // used to check if there were any unchecked conversions
1841 Warner overrideWarner = new Warner();
1842
1843 /** Check that a class does not inherit two concrete methods
1844 * with the same signature.
1845 * @param pos Position to be used for error reporting.
1846 * @param site The class type to be checked.
1847 */
1848 public void checkCompatibleConcretes(DiagnosticPosition pos, Type site) {
1849 Type sup = types.supertype(site);
1850 if (!sup.hasTag(CLASS)) return;
1851
1852 for (Type t1 = sup;
1853 t1.hasTag(CLASS) && t1.tsym.type.isParameterized();
1854 t1 = types.supertype(t1)) {
1855 for (Symbol s1 : t1.tsym.members().getSymbols(NON_RECURSIVE)) {
1856 if (s1.kind != MTH ||
1857 (s1.flags() & (STATIC|SYNTHETIC|BRIDGE)) != 0 ||
1858 !s1.isInheritedIn(site.tsym, types) ||
1859 ((MethodSymbol)s1).implementation(site.tsym,
1860 types,
1861 true) != s1)
1862 continue;
1863 Type st1 = types.memberType(t1, s1);
1864 int s1ArgsLength = st1.getParameterTypes().length();
1865 if (st1 == s1.type) continue;
1866
1867 for (Type t2 = sup;
1868 t2.hasTag(CLASS);
1869 t2 = types.supertype(t2)) {
1870 for (Symbol s2 : t2.tsym.members().getSymbolsByName(s1.name)) {
1871 if (s2 == s1 ||
1872 s2.kind != MTH ||
1873 (s2.flags() & (STATIC|SYNTHETIC|BRIDGE)) != 0 ||
1874 s2.type.getParameterTypes().length() != s1ArgsLength ||
1875 !s2.isInheritedIn(site.tsym, types) ||
1876 ((MethodSymbol)s2).implementation(site.tsym,
1877 types,
1878 true) != s2)
1879 continue;
1880 Type st2 = types.memberType(t2, s2);
1881 if (types.overrideEquivalent(st1, st2))
1882 log.error(pos, "concrete.inheritance.conflict",
1883 s1, t1, s2, t2, sup);
1884 }
1885 }
1886 }
1887 }
1888 }
1889
1890 /** Check that classes (or interfaces) do not each define an abstract
1891 * method with same name and arguments but incompatible return types.
1892 * @param pos Position to be used for error reporting.
1893 * @param t1 The first argument type.
1894 * @param t2 The second argument type.
1895 */
1896 public boolean checkCompatibleAbstracts(DiagnosticPosition pos,
1897 Type t1,
1898 Type t2,
1899 Type site) {
1900 if ((site.tsym.flags() & COMPOUND) != 0) {
1901 // special case for intersections: need to eliminate wildcards in supertypes
1902 t1 = types.capture(t1);
1903 t2 = types.capture(t2);
1904 }
1905 return firstIncompatibility(pos, t1, t2, site) == null;
1906 }
1907
1908 /** Return the first method which is defined with same args
1909 * but different return types in two given interfaces, or null if none
1910 * exists.
1911 * @param t1 The first type.
1912 * @param t2 The second type.
1913 * @param site The most derived type.
1914 * @returns symbol from t2 that conflicts with one in t1.
1915 */
1916 private Symbol firstIncompatibility(DiagnosticPosition pos, Type t1, Type t2, Type site) {
1917 Map<TypeSymbol,Type> interfaces1 = new HashMap<>();
1918 closure(t1, interfaces1);
1919 Map<TypeSymbol,Type> interfaces2;
1920 if (t1 == t2)
1921 interfaces2 = interfaces1;
1922 else
1923 closure(t2, interfaces1, interfaces2 = new HashMap<>());
1924
1925 for (Type t3 : interfaces1.values()) {
1926 for (Type t4 : interfaces2.values()) {
1927 Symbol s = firstDirectIncompatibility(pos, t3, t4, site);
1928 if (s != null) return s;
1929 }
1930 }
1931 return null;
1932 }
1933
1934 /** Compute all the supertypes of t, indexed by type symbol. */
1935 private void closure(Type t, Map<TypeSymbol,Type> typeMap) {
1936 if (!t.hasTag(CLASS)) return;
1937 if (typeMap.put(t.tsym, t) == null) {
1938 closure(types.supertype(t), typeMap);
1939 for (Type i : types.interfaces(t))
1940 closure(i, typeMap);
1941 }
1942 }
1943
1944 /** Compute all the supertypes of t, indexed by type symbol (except thise in typesSkip). */
1945 private void closure(Type t, Map<TypeSymbol,Type> typesSkip, Map<TypeSymbol,Type> typeMap) {
1946 if (!t.hasTag(CLASS)) return;
1947 if (typesSkip.get(t.tsym) != null) return;
1948 if (typeMap.put(t.tsym, t) == null) {
1949 closure(types.supertype(t), typesSkip, typeMap);
1950 for (Type i : types.interfaces(t))
1951 closure(i, typesSkip, typeMap);
1952 }
1953 }
1954
1955 /** Return the first method in t2 that conflicts with a method from t1. */
1956 private Symbol firstDirectIncompatibility(DiagnosticPosition pos, Type t1, Type t2, Type site) {
1957 for (Symbol s1 : t1.tsym.members().getSymbols(NON_RECURSIVE)) {
1958 Type st1 = null;
1959 if (s1.kind != MTH || !s1.isInheritedIn(site.tsym, types) ||
1960 (s1.flags() & SYNTHETIC) != 0) continue;
1961 Symbol impl = ((MethodSymbol)s1).implementation(site.tsym, types, false);
1962 if (impl != null && (impl.flags() & ABSTRACT) == 0) continue;
1963 for (Symbol s2 : t2.tsym.members().getSymbolsByName(s1.name)) {
1964 if (s1 == s2) continue;
1965 if (s2.kind != MTH || !s2.isInheritedIn(site.tsym, types) ||
1966 (s2.flags() & SYNTHETIC) != 0) continue;
1967 if (st1 == null) st1 = types.memberType(t1, s1);
1968 Type st2 = types.memberType(t2, s2);
1969 if (types.overrideEquivalent(st1, st2)) {
1970 List<Type> tvars1 = st1.getTypeArguments();
1971 List<Type> tvars2 = st2.getTypeArguments();
1972 Type rt1 = st1.getReturnType();
1973 Type rt2 = types.subst(st2.getReturnType(), tvars2, tvars1);
1974 boolean compat =
1975 types.isSameType(rt1, rt2) ||
1976 !rt1.isPrimitiveOrVoid() &&
1977 !rt2.isPrimitiveOrVoid() &&
1978 (types.covariantReturnType(rt1, rt2, types.noWarnings) ||
1979 types.covariantReturnType(rt2, rt1, types.noWarnings)) ||
1980 checkCommonOverriderIn(s1,s2,site);
1981 if (!compat) {
1982 log.error(pos, "types.incompatible.diff.ret",
1983 t1, t2, s2.name +
1984 "(" + types.memberType(t2, s2).getParameterTypes() + ")");
1985 return s2;
1986 }
1987 } else if (checkNameClash((ClassSymbol)site.tsym, s1, s2) &&
1988 !checkCommonOverriderIn(s1, s2, site)) {
1989 log.error(pos,
1990 "name.clash.same.erasure.no.override",
1991 s1, s1.location(),
1992 s2, s2.location());
1993 return s2;
1994 }
1995 }
1996 }
1997 return null;
1998 }
1999 //WHERE
2000 boolean checkCommonOverriderIn(Symbol s1, Symbol s2, Type site) {
2001 Map<TypeSymbol,Type> supertypes = new HashMap<>();
2002 Type st1 = types.memberType(site, s1);
2003 Type st2 = types.memberType(site, s2);
2004 closure(site, supertypes);
2005 for (Type t : supertypes.values()) {
2006 for (Symbol s3 : t.tsym.members().getSymbolsByName(s1.name)) {
2007 if (s3 == s1 || s3 == s2 || s3.kind != MTH || (s3.flags() & (BRIDGE|SYNTHETIC)) != 0) continue;
2008 Type st3 = types.memberType(site,s3);
2009 if (types.overrideEquivalent(st3, st1) &&
2010 types.overrideEquivalent(st3, st2) &&
2011 types.returnTypeSubstitutable(st3, st1) &&
2012 types.returnTypeSubstitutable(st3, st2)) {
2013 return true;
2014 }
2015 }
2016 }
2017 return false;
2018 }
2019
2020 /** Check that a given method conforms with any method it overrides.
2021 * @param tree The tree from which positions are extracted
2022 * for errors.
2023 * @param m The overriding method.
2024 */
2025 void checkOverride(Env<AttrContext> env, JCMethodDecl tree, MethodSymbol m) {
2026 ClassSymbol origin = (ClassSymbol)m.owner;
2027 if ((origin.flags() & ENUM) != 0 && names.finalize.equals(m.name))
2028 if (m.overrides(syms.enumFinalFinalize, origin, types, false)) {
2029 log.error(tree.pos(), "enum.no.finalize");
2030 return;
2031 }
2032 for (Type t = origin.type; t.hasTag(CLASS);
2033 t = types.supertype(t)) {
2034 if (t != origin.type) {
2035 checkOverride(tree, t, origin, m);
2036 }
2037 for (Type t2 : types.interfaces(t)) {
2038 checkOverride(tree, t2, origin, m);
2039 }
2040 }
2041
2042 final boolean explicitOverride = m.attribute(syms.overrideType.tsym) != null;
2043 // Check if this method must override a super method due to being annotated with @Override
2044 // or by virtue of being a member of a diamond inferred anonymous class. Latter case is to
2045 // be treated "as if as they were annotated" with @Override.
2046 boolean mustOverride = explicitOverride ||
2047 (env.info.isAnonymousDiamond && !m.isConstructor() && !m.isPrivate());
2048 if (mustOverride && !isOverrider(m)) {
2049 DiagnosticPosition pos = tree.pos();
2050 for (JCAnnotation a : tree.getModifiers().annotations) {
2051 if (a.annotationType.type.tsym == syms.overrideType.tsym) {
2052 pos = a.pos();
2053 break;
2054 }
2055 }
2056 log.error(pos,
2057 explicitOverride ? Errors.MethodDoesNotOverrideSuperclass :
2058 Errors.AnonymousDiamondMethodDoesNotOverrideSuperclass(Fragments.DiamondAnonymousMethodsImplicitlyOverride));
2059 }
2060 }
2061
2062 void checkOverride(JCTree tree, Type site, ClassSymbol origin, MethodSymbol m) {
2063 TypeSymbol c = site.tsym;
2064 for (Symbol sym : c.members().getSymbolsByName(m.name)) {
2065 if (m.overrides(sym, origin, types, false)) {
2066 if ((sym.flags() & ABSTRACT) == 0) {
2067 checkOverride(tree, m, (MethodSymbol)sym, origin);
2068 }
2069 }
2070 }
2071 }
2072
2073 private Filter<Symbol> equalsHasCodeFilter = new Filter<Symbol>() {
2074 public boolean accepts(Symbol s) {
2075 return MethodSymbol.implementation_filter.accepts(s) &&
2076 (s.flags() & BAD_OVERRIDE) == 0;
2077
2078 }
2079 };
2080
2081 public void checkClassOverrideEqualsAndHashIfNeeded(DiagnosticPosition pos,
2082 ClassSymbol someClass) {
2083 /* At present, annotations cannot possibly have a method that is override
2084 * equivalent with Object.equals(Object) but in any case the condition is
2085 * fine for completeness.
2086 */
2087 if (someClass == (ClassSymbol)syms.objectType.tsym ||
2088 someClass.isInterface() || someClass.isEnum() ||
2089 (someClass.flags() & ANNOTATION) != 0 ||
2090 (someClass.flags() & ABSTRACT) != 0) return;
2091 //anonymous inner classes implementing interfaces need especial treatment
2092 if (someClass.isAnonymous()) {
2093 List<Type> interfaces = types.interfaces(someClass.type);
2094 if (interfaces != null && !interfaces.isEmpty() &&
2095 interfaces.head.tsym == syms.comparatorType.tsym) return;
2096 }
2097 checkClassOverrideEqualsAndHash(pos, someClass);
2098 }
2099
2100 private void checkClassOverrideEqualsAndHash(DiagnosticPosition pos,
2101 ClassSymbol someClass) {
2102 if (lint.isEnabled(LintCategory.OVERRIDES)) {
2103 MethodSymbol equalsAtObject = (MethodSymbol)syms.objectType
2104 .tsym.members().findFirst(names.equals);
2105 MethodSymbol hashCodeAtObject = (MethodSymbol)syms.objectType
2106 .tsym.members().findFirst(names.hashCode);
2107 boolean overridesEquals = types.implementation(equalsAtObject,
2108 someClass, false, equalsHasCodeFilter).owner == someClass;
2109 boolean overridesHashCode = types.implementation(hashCodeAtObject,
2110 someClass, false, equalsHasCodeFilter) != hashCodeAtObject;
2111
2112 if (overridesEquals && !overridesHashCode) {
2113 log.warning(LintCategory.OVERRIDES, pos,
2114 "override.equals.but.not.hashcode", someClass);
2115 }
2116 }
2117 }
2118
2119 private boolean checkNameClash(ClassSymbol origin, Symbol s1, Symbol s2) {
2120 ClashFilter cf = new ClashFilter(origin.type);
2121 return (cf.accepts(s1) &&
2122 cf.accepts(s2) &&
2123 types.hasSameArgs(s1.erasure(types), s2.erasure(types)));
2124 }
2125
2126
2127 /** Check that all abstract members of given class have definitions.
2128 * @param pos Position to be used for error reporting.
2129 * @param c The class.
2130 */
2131 void checkAllDefined(DiagnosticPosition pos, ClassSymbol c) {
2132 MethodSymbol undef = types.firstUnimplementedAbstract(c);
2133 if (undef != null) {
2134 MethodSymbol undef1 =
2135 new MethodSymbol(undef.flags(), undef.name,
2136 types.memberType(c.type, undef), undef.owner);
2137 log.error(pos, "does.not.override.abstract",
2138 c, undef1, undef1.location());
2139 }
2140 }
2141
2142 void checkNonCyclicDecl(JCClassDecl tree) {
2143 CycleChecker cc = new CycleChecker();
2144 cc.scan(tree);
2145 if (!cc.errorFound && !cc.partialCheck) {
2146 tree.sym.flags_field |= ACYCLIC;
2147 }
2148 }
2149
2150 class CycleChecker extends TreeScanner {
2151
2152 List<Symbol> seenClasses = List.nil();
2153 boolean errorFound = false;
2154 boolean partialCheck = false;
2155
2156 private void checkSymbol(DiagnosticPosition pos, Symbol sym) {
2157 if (sym != null && sym.kind == TYP) {
2158 Env<AttrContext> classEnv = enter.getEnv((TypeSymbol)sym);
2159 if (classEnv != null) {
2160 DiagnosticSource prevSource = log.currentSource();
2161 try {
2162 log.useSource(classEnv.toplevel.sourcefile);
2163 scan(classEnv.tree);
2164 }
2165 finally {
2166 log.useSource(prevSource.getFile());
2167 }
2168 } else if (sym.kind == TYP) {
2169 checkClass(pos, sym, List.<JCTree>nil());
2170 }
2171 } else {
2172 //not completed yet
2173 partialCheck = true;
2174 }
2175 }
2176
2177 @Override
2178 public void visitSelect(JCFieldAccess tree) {
2179 super.visitSelect(tree);
2180 checkSymbol(tree.pos(), tree.sym);
2181 }
2182
2183 @Override
2184 public void visitIdent(JCIdent tree) {
2185 checkSymbol(tree.pos(), tree.sym);
2186 }
2187
2188 @Override
2189 public void visitTypeApply(JCTypeApply tree) {
2190 scan(tree.clazz);
2191 }
2192
2193 @Override
2194 public void visitTypeArray(JCArrayTypeTree tree) {
2195 scan(tree.elemtype);
2196 }
2197
2198 @Override
2199 public void visitClassDef(JCClassDecl tree) {
2200 List<JCTree> supertypes = List.nil();
2201 if (tree.getExtendsClause() != null) {
2202 supertypes = supertypes.prepend(tree.getExtendsClause());
2203 }
2204 if (tree.getImplementsClause() != null) {
2205 for (JCTree intf : tree.getImplementsClause()) {
2206 supertypes = supertypes.prepend(intf);
2207 }
2208 }
2209 checkClass(tree.pos(), tree.sym, supertypes);
2210 }
2211
2212 void checkClass(DiagnosticPosition pos, Symbol c, List<JCTree> supertypes) {
2213 if ((c.flags_field & ACYCLIC) != 0)
2214 return;
2215 if (seenClasses.contains(c)) {
2216 errorFound = true;
2217 noteCyclic(pos, (ClassSymbol)c);
2218 } else if (!c.type.isErroneous()) {
2219 try {
2220 seenClasses = seenClasses.prepend(c);
2221 if (c.type.hasTag(CLASS)) {
2222 if (supertypes.nonEmpty()) {
2223 scan(supertypes);
2224 }
2225 else {
2226 ClassType ct = (ClassType)c.type;
2227 if (ct.supertype_field == null ||
2228 ct.interfaces_field == null) {
2229 //not completed yet
2230 partialCheck = true;
2231 return;
2232 }
2233 checkSymbol(pos, ct.supertype_field.tsym);
2234 for (Type intf : ct.interfaces_field) {
2235 checkSymbol(pos, intf.tsym);
2236 }
2237 }
2238 if (c.owner.kind == TYP) {
2239 checkSymbol(pos, c.owner);
2240 }
2241 }
2242 } finally {
2243 seenClasses = seenClasses.tail;
2244 }
2245 }
2246 }
2247 }
2248
2249 /** Check for cyclic references. Issue an error if the
2250 * symbol of the type referred to has a LOCKED flag set.
2251 *
2252 * @param pos Position to be used for error reporting.
2253 * @param t The type referred to.
2254 */
2255 void checkNonCyclic(DiagnosticPosition pos, Type t) {
2256 checkNonCyclicInternal(pos, t);
2257 }
2258
2259
2260 void checkNonCyclic(DiagnosticPosition pos, TypeVar t) {
2261 checkNonCyclic1(pos, t, List.<TypeVar>nil());
2262 }
2263
2264 private void checkNonCyclic1(DiagnosticPosition pos, Type t, List<TypeVar> seen) {
2265 final TypeVar tv;
2266 if (t.hasTag(TYPEVAR) && (t.tsym.flags() & UNATTRIBUTED) != 0)
2267 return;
2268 if (seen.contains(t)) {
2269 tv = (TypeVar)t;
2270 tv.bound = types.createErrorType(t);
2271 log.error(pos, "cyclic.inheritance", t);
2272 } else if (t.hasTag(TYPEVAR)) {
2273 tv = (TypeVar)t;
2274 seen = seen.prepend(tv);
2275 for (Type b : types.getBounds(tv))
2276 checkNonCyclic1(pos, b, seen);
2277 }
2278 }
2279
2280 /** Check for cyclic references. Issue an error if the
2281 * symbol of the type referred to has a LOCKED flag set.
2282 *
2283 * @param pos Position to be used for error reporting.
2284 * @param t The type referred to.
2285 * @returns True if the check completed on all attributed classes
2286 */
2287 private boolean checkNonCyclicInternal(DiagnosticPosition pos, Type t) {
2288 boolean complete = true; // was the check complete?
2289 //- System.err.println("checkNonCyclicInternal("+t+");");//DEBUG
2290 Symbol c = t.tsym;
2291 if ((c.flags_field & ACYCLIC) != 0) return true;
2292
2293 if ((c.flags_field & LOCKED) != 0) {
2294 noteCyclic(pos, (ClassSymbol)c);
2295 } else if (!c.type.isErroneous()) {
2296 try {
2297 c.flags_field |= LOCKED;
2298 if (c.type.hasTag(CLASS)) {
2299 ClassType clazz = (ClassType)c.type;
2300 if (clazz.interfaces_field != null)
2301 for (List<Type> l=clazz.interfaces_field; l.nonEmpty(); l=l.tail)
2302 complete &= checkNonCyclicInternal(pos, l.head);
2303 if (clazz.supertype_field != null) {
2304 Type st = clazz.supertype_field;
2305 if (st != null && st.hasTag(CLASS))
2306 complete &= checkNonCyclicInternal(pos, st);
2307 }
2308 if (c.owner.kind == TYP)
2309 complete &= checkNonCyclicInternal(pos, c.owner.type);
2310 }
2311 } finally {
2312 c.flags_field &= ~LOCKED;
2313 }
2314 }
2315 if (complete)
2316 complete = ((c.flags_field & UNATTRIBUTED) == 0) && c.isCompleted();
2317 if (complete) c.flags_field |= ACYCLIC;
2318 return complete;
2319 }
2320
2321 /** Note that we found an inheritance cycle. */
2322 private void noteCyclic(DiagnosticPosition pos, ClassSymbol c) {
2323 log.error(pos, "cyclic.inheritance", c);
2324 for (List<Type> l=types.interfaces(c.type); l.nonEmpty(); l=l.tail)
2325 l.head = types.createErrorType((ClassSymbol)l.head.tsym, Type.noType);
2326 Type st = types.supertype(c.type);
2327 if (st.hasTag(CLASS))
2328 ((ClassType)c.type).supertype_field = types.createErrorType((ClassSymbol)st.tsym, Type.noType);
2329 c.type = types.createErrorType(c, c.type);
2330 c.flags_field |= ACYCLIC;
2331 }
2332
2333 /** Check that all methods which implement some
2334 * method conform to the method they implement.
2335 * @param tree The class definition whose members are checked.
2336 */
2337 void checkImplementations(JCClassDecl tree) {
2338 checkImplementations(tree, tree.sym, tree.sym);
2339 }
2340 //where
2341 /** Check that all methods which implement some
2342 * method in `ic' conform to the method they implement.
2343 */
2344 void checkImplementations(JCTree tree, ClassSymbol origin, ClassSymbol ic) {
2345 for (List<Type> l = types.closure(ic.type); l.nonEmpty(); l = l.tail) {
2346 ClassSymbol lc = (ClassSymbol)l.head.tsym;
2347 if ((lc.flags() & ABSTRACT) != 0) {
2348 for (Symbol sym : lc.members().getSymbols(NON_RECURSIVE)) {
2349 if (sym.kind == MTH &&
2350 (sym.flags() & (STATIC|ABSTRACT)) == ABSTRACT) {
2351 MethodSymbol absmeth = (MethodSymbol)sym;
2352 MethodSymbol implmeth = absmeth.implementation(origin, types, false);
2353 if (implmeth != null && implmeth != absmeth &&
2354 (implmeth.owner.flags() & INTERFACE) ==
2355 (origin.flags() & INTERFACE)) {
2356 // don't check if implmeth is in a class, yet
2357 // origin is an interface. This case arises only
2358 // if implmeth is declared in Object. The reason is
2359 // that interfaces really don't inherit from
2360 // Object it's just that the compiler represents
2361 // things that way.
2362 checkOverride(tree, implmeth, absmeth, origin);
2363 }
2364 }
2365 }
2366 }
2367 }
2368 }
2369
2370 /** Check that all abstract methods implemented by a class are
2371 * mutually compatible.
2372 * @param pos Position to be used for error reporting.
2373 * @param c The class whose interfaces are checked.
2374 */
2375 void checkCompatibleSupertypes(DiagnosticPosition pos, Type c) {
2376 List<Type> supertypes = types.interfaces(c);
2377 Type supertype = types.supertype(c);
2378 if (supertype.hasTag(CLASS) &&
2379 (supertype.tsym.flags() & ABSTRACT) != 0)
2380 supertypes = supertypes.prepend(supertype);
2381 for (List<Type> l = supertypes; l.nonEmpty(); l = l.tail) {
2382 if (!l.head.getTypeArguments().isEmpty() &&
2383 !checkCompatibleAbstracts(pos, l.head, l.head, c))
2384 return;
2385 for (List<Type> m = supertypes; m != l; m = m.tail)
2386 if (!checkCompatibleAbstracts(pos, l.head, m.head, c))
2387 return;
2388 }
2389 checkCompatibleConcretes(pos, c);
2390 }
2391
2392 void checkConflicts(DiagnosticPosition pos, Symbol sym, TypeSymbol c) {
2393 for (Type ct = c.type; ct != Type.noType ; ct = types.supertype(ct)) {
2394 for (Symbol sym2 : ct.tsym.members().getSymbolsByName(sym.name, NON_RECURSIVE)) {
2395 // VM allows methods and variables with differing types
2396 if (sym.kind == sym2.kind &&
2397 types.isSameType(types.erasure(sym.type), types.erasure(sym2.type)) &&
2398 sym != sym2 &&
2399 (sym.flags() & Flags.SYNTHETIC) != (sym2.flags() & Flags.SYNTHETIC) &&
2400 (sym.flags() & BRIDGE) == 0 && (sym2.flags() & BRIDGE) == 0) {
2401 syntheticError(pos, (sym2.flags() & SYNTHETIC) == 0 ? sym2 : sym);
2402 return;
2403 }
2404 }
2405 }
2406 }
2407
2408 /** Check that all non-override equivalent methods accessible from 'site'
2409 * are mutually compatible (JLS 8.4.8/9.4.1).
2410 *
2411 * @param pos Position to be used for error reporting.
2412 * @param site The class whose methods are checked.
2413 * @param sym The method symbol to be checked.
2414 */
2415 void checkOverrideClashes(DiagnosticPosition pos, Type site, MethodSymbol sym) {
2416 ClashFilter cf = new ClashFilter(site);
2417 //for each method m1 that is overridden (directly or indirectly)
2418 //by method 'sym' in 'site'...
2419
2420 List<MethodSymbol> potentiallyAmbiguousList = List.nil();
2421 boolean overridesAny = false;
2422 for (Symbol m1 : types.membersClosure(site, false).getSymbolsByName(sym.name, cf)) {
2423 if (!sym.overrides(m1, site.tsym, types, false)) {
2424 if (m1 == sym) {
2425 continue;
2426 }
2427
2428 if (!overridesAny) {
2429 potentiallyAmbiguousList = potentiallyAmbiguousList.prepend((MethodSymbol)m1);
2430 }
2431 continue;
2432 }
2433
2434 if (m1 != sym) {
2435 overridesAny = true;
2436 potentiallyAmbiguousList = List.nil();
2437 }
2438
2439 //...check each method m2 that is a member of 'site'
2440 for (Symbol m2 : types.membersClosure(site, false).getSymbolsByName(sym.name, cf)) {
2441 if (m2 == m1) continue;
2442 //if (i) the signature of 'sym' is not a subsignature of m1 (seen as
2443 //a member of 'site') and (ii) m1 has the same erasure as m2, issue an error
2444 if (!types.isSubSignature(sym.type, types.memberType(site, m2), allowStrictMethodClashCheck) &&
2445 types.hasSameArgs(m2.erasure(types), m1.erasure(types))) {
2446 sym.flags_field |= CLASH;
2447 String key = m1 == sym ?
2448 "name.clash.same.erasure.no.override" :
2449 "name.clash.same.erasure.no.override.1";
2450 log.error(pos,
2451 key,
2452 sym, sym.location(),
2453 m2, m2.location(),
2454 m1, m1.location());
2455 return;
2456 }
2457 }
2458 }
2459
2460 if (!overridesAny) {
2461 for (MethodSymbol m: potentiallyAmbiguousList) {
2462 checkPotentiallyAmbiguousOverloads(pos, site, sym, m);
2463 }
2464 }
2465 }
2466
2467 /** Check that all static methods accessible from 'site' are
2468 * mutually compatible (JLS 8.4.8).
2469 *
2470 * @param pos Position to be used for error reporting.
2471 * @param site The class whose methods are checked.
2472 * @param sym The method symbol to be checked.
2473 */
2474 void checkHideClashes(DiagnosticPosition pos, Type site, MethodSymbol sym) {
2475 ClashFilter cf = new ClashFilter(site);
2476 //for each method m1 that is a member of 'site'...
2477 for (Symbol s : types.membersClosure(site, true).getSymbolsByName(sym.name, cf)) {
2478 //if (i) the signature of 'sym' is not a subsignature of m1 (seen as
2479 //a member of 'site') and (ii) 'sym' has the same erasure as m1, issue an error
2480 if (!types.isSubSignature(sym.type, types.memberType(site, s), allowStrictMethodClashCheck)) {
2481 if (types.hasSameArgs(s.erasure(types), sym.erasure(types))) {
2482 log.error(pos,
2483 "name.clash.same.erasure.no.hide",
2484 sym, sym.location(),
2485 s, s.location());
2486 return;
2487 } else {
2488 checkPotentiallyAmbiguousOverloads(pos, site, sym, (MethodSymbol)s);
2489 }
2490 }
2491 }
2492 }
2493
2494 //where
2495 private class ClashFilter implements Filter<Symbol> {
2496
2497 Type site;
2498
2499 ClashFilter(Type site) {
2500 this.site = site;
2501 }
2502
2503 boolean shouldSkip(Symbol s) {
2504 return (s.flags() & CLASH) != 0 &&
2505 s.owner == site.tsym;
2506 }
2507
2508 public boolean accepts(Symbol s) {
2509 return s.kind == MTH &&
2510 (s.flags() & SYNTHETIC) == 0 &&
2511 !shouldSkip(s) &&
2512 s.isInheritedIn(site.tsym, types) &&
2513 !s.isConstructor();
2514 }
2515 }
2516
2517 void checkDefaultMethodClashes(DiagnosticPosition pos, Type site) {
2518 DefaultMethodClashFilter dcf = new DefaultMethodClashFilter(site);
2519 for (Symbol m : types.membersClosure(site, false).getSymbols(dcf)) {
2520 Assert.check(m.kind == MTH);
2521 List<MethodSymbol> prov = types.interfaceCandidates(site, (MethodSymbol)m);
2522 if (prov.size() > 1) {
2523 ListBuffer<Symbol> abstracts = new ListBuffer<>();
2524 ListBuffer<Symbol> defaults = new ListBuffer<>();
2525 for (MethodSymbol provSym : prov) {
2526 if ((provSym.flags() & DEFAULT) != 0) {
2527 defaults = defaults.append(provSym);
2528 } else if ((provSym.flags() & ABSTRACT) != 0) {
2529 abstracts = abstracts.append(provSym);
2530 }
2531 if (defaults.nonEmpty() && defaults.size() + abstracts.size() >= 2) {
2532 //strong semantics - issue an error if two sibling interfaces
2533 //have two override-equivalent defaults - or if one is abstract
2534 //and the other is default
2535 String errKey;
2536 Symbol s1 = defaults.first();
2537 Symbol s2;
2538 if (defaults.size() > 1) {
2539 errKey = "types.incompatible.unrelated.defaults";
2540 s2 = defaults.toList().tail.head;
2541 } else {
2542 errKey = "types.incompatible.abstract.default";
2543 s2 = abstracts.first();
2544 }
2545 log.error(pos, errKey,
2546 Kinds.kindName(site.tsym), site,
2547 m.name, types.memberType(site, m).getParameterTypes(),
2548 s1.location(), s2.location());
2549 break;
2550 }
2551 }
2552 }
2553 }
2554 }
2555
2556 //where
2557 private class DefaultMethodClashFilter implements Filter<Symbol> {
2558
2559 Type site;
2560
2561 DefaultMethodClashFilter(Type site) {
2562 this.site = site;
2563 }
2564
2565 public boolean accepts(Symbol s) {
2566 return s.kind == MTH &&
2567 (s.flags() & DEFAULT) != 0 &&
2568 s.isInheritedIn(site.tsym, types) &&
2569 !s.isConstructor();
2570 }
2571 }
2572
2573 /**
2574 * Report warnings for potentially ambiguous method declarations. Two declarations
2575 * are potentially ambiguous if they feature two unrelated functional interface
2576 * in same argument position (in which case, a call site passing an implicit
2577 * lambda would be ambiguous).
2578 */
2579 void checkPotentiallyAmbiguousOverloads(DiagnosticPosition pos, Type site,
2580 MethodSymbol msym1, MethodSymbol msym2) {
2581 if (msym1 != msym2 &&
2582 allowDefaultMethods &&
2583 lint.isEnabled(LintCategory.OVERLOADS) &&
2584 (msym1.flags() & POTENTIALLY_AMBIGUOUS) == 0 &&
2585 (msym2.flags() & POTENTIALLY_AMBIGUOUS) == 0) {
2586 Type mt1 = types.memberType(site, msym1);
2587 Type mt2 = types.memberType(site, msym2);
2588 //if both generic methods, adjust type variables
2589 if (mt1.hasTag(FORALL) && mt2.hasTag(FORALL) &&
2590 types.hasSameBounds((ForAll)mt1, (ForAll)mt2)) {
2591 mt2 = types.subst(mt2, ((ForAll)mt2).tvars, ((ForAll)mt1).tvars);
2592 }
2593 //expand varargs methods if needed
2594 int maxLength = Math.max(mt1.getParameterTypes().length(), mt2.getParameterTypes().length());
2595 List<Type> args1 = rs.adjustArgs(mt1.getParameterTypes(), msym1, maxLength, true);
2596 List<Type> args2 = rs.adjustArgs(mt2.getParameterTypes(), msym2, maxLength, true);
2597 //if arities don't match, exit
2598 if (args1.length() != args2.length()) return;
2599 boolean potentiallyAmbiguous = false;
2600 while (args1.nonEmpty() && args2.nonEmpty()) {
2601 Type s = args1.head;
2602 Type t = args2.head;
2603 if (!types.isSubtype(t, s) && !types.isSubtype(s, t)) {
2604 if (types.isFunctionalInterface(s) && types.isFunctionalInterface(t) &&
2605 types.findDescriptorType(s).getParameterTypes().length() > 0 &&
2606 types.findDescriptorType(s).getParameterTypes().length() ==
2607 types.findDescriptorType(t).getParameterTypes().length()) {
2608 potentiallyAmbiguous = true;
2609 } else {
2610 break;
2611 }
2612 }
2613 args1 = args1.tail;
2614 args2 = args2.tail;
2615 }
2616 if (potentiallyAmbiguous) {
2617 //we found two incompatible functional interfaces with same arity
2618 //this means a call site passing an implicit lambda would be ambigiuous
2619 msym1.flags_field |= POTENTIALLY_AMBIGUOUS;
2620 msym2.flags_field |= POTENTIALLY_AMBIGUOUS;
2621 log.warning(LintCategory.OVERLOADS, pos, "potentially.ambiguous.overload",
2622 msym1, msym1.location(),
2623 msym2, msym2.location());
2624 return;
2625 }
2626 }
2627 }
2628
2629 void checkAccessFromSerializableElement(final JCTree tree, boolean isLambda) {
2630 if (warnOnAnyAccessToMembers ||
2631 (lint.isEnabled(LintCategory.SERIAL) &&
2632 !lint.isSuppressed(LintCategory.SERIAL) &&
2633 isLambda)) {
2634 Symbol sym = TreeInfo.symbol(tree);
2635 if (!sym.kind.matches(KindSelector.VAL_MTH)) {
2636 return;
2637 }
2638
2639 if (sym.kind == VAR) {
2640 if ((sym.flags() & PARAMETER) != 0 ||
2641 sym.isLocal() ||
2642 sym.name == names._this ||
2643 sym.name == names._super) {
2644 return;
2645 }
2646 }
2647
2648 if (!types.isSubtype(sym.owner.type, syms.serializableType) &&
2649 isEffectivelyNonPublic(sym)) {
2650 if (isLambda) {
2651 if (belongsToRestrictedPackage(sym)) {
2652 log.warning(LintCategory.SERIAL, tree.pos(),
2653 "access.to.member.from.serializable.lambda", sym);
2654 }
2655 } else {
2656 log.warning(tree.pos(),
2657 "access.to.member.from.serializable.element", sym);
2658 }
2659 }
2660 }
2661 }
2662
2663 private boolean isEffectivelyNonPublic(Symbol sym) {
2664 if (sym.packge() == syms.rootPackage) {
2665 return false;
2666 }
2667
2668 while (sym.kind != PCK) {
2669 if ((sym.flags() & PUBLIC) == 0) {
2670 return true;
2671 }
2672 sym = sym.owner;
2673 }
2674 return false;
2675 }
2676
2677 private boolean belongsToRestrictedPackage(Symbol sym) {
2678 String fullName = sym.packge().fullname.toString();
2679 return fullName.startsWith("java.") ||
2680 fullName.startsWith("javax.") ||
2681 fullName.startsWith("sun.") ||
2682 fullName.contains(".internal.");
2683 }
2684
2685 /** Report a conflict between a user symbol and a synthetic symbol.
2686 */
2687 private void syntheticError(DiagnosticPosition pos, Symbol sym) {
2688 if (!sym.type.isErroneous()) {
2689 log.error(pos, "synthetic.name.conflict", sym, sym.location());
2690 }
2691 }
2692
2693 /** Check that class c does not implement directly or indirectly
2694 * the same parameterized interface with two different argument lists.
2695 * @param pos Position to be used for error reporting.
2696 * @param type The type whose interfaces are checked.
2697 */
2698 void checkClassBounds(DiagnosticPosition pos, Type type) {
2699 checkClassBounds(pos, new HashMap<TypeSymbol,Type>(), type);
2700 }
2701 //where
2702 /** Enter all interfaces of type `type' into the hash table `seensofar'
2703 * with their class symbol as key and their type as value. Make
2704 * sure no class is entered with two different types.
2705 */
2706 void checkClassBounds(DiagnosticPosition pos,
2707 Map<TypeSymbol,Type> seensofar,
2708 Type type) {
2709 if (type.isErroneous()) return;
2710 for (List<Type> l = types.interfaces(type); l.nonEmpty(); l = l.tail) {
2711 Type it = l.head;
2712 Type oldit = seensofar.put(it.tsym, it);
2713 if (oldit != null) {
2714 List<Type> oldparams = oldit.allparams();
2715 List<Type> newparams = it.allparams();
2716 if (!types.containsTypeEquivalent(oldparams, newparams))
2717 log.error(pos, "cant.inherit.diff.arg",
2718 it.tsym, Type.toString(oldparams),
2719 Type.toString(newparams));
2720 }
2721 checkClassBounds(pos, seensofar, it);
2722 }
2723 Type st = types.supertype(type);
2724 if (st != Type.noType) checkClassBounds(pos, seensofar, st);
2725 }
2726
2727 /** Enter interface into into set.
2728 * If it existed already, issue a "repeated interface" error.
2729 */
2730 void checkNotRepeated(DiagnosticPosition pos, Type it, Set<Type> its) {
2731 if (its.contains(it))
2732 log.error(pos, "repeated.interface");
2733 else {
2734 its.add(it);
2735 }
2736 }
2737
2738 /* *************************************************************************
2739 * Check annotations
2740 **************************************************************************/
2741
2742 /**
2743 * Recursively validate annotations values
2744 */
2745 void validateAnnotationTree(JCTree tree) {
2746 class AnnotationValidator extends TreeScanner {
2747 @Override
2748 public void visitAnnotation(JCAnnotation tree) {
2749 if (!tree.type.isErroneous()) {
2750 super.visitAnnotation(tree);
2751 validateAnnotation(tree);
2752 }
2753 }
2754 }
2755 tree.accept(new AnnotationValidator());
2756 }
2757
2758 /**
2759 * {@literal
2760 * Annotation types are restricted to primitives, String, an
2761 * enum, an annotation, Class, Class<?>, Class<? extends
2762 * Anything>, arrays of the preceding.
2763 * }
2764 */
2765 void validateAnnotationType(JCTree restype) {
2766 // restype may be null if an error occurred, so don't bother validating it
2767 if (restype != null) {
2768 validateAnnotationType(restype.pos(), restype.type);
2769 }
2770 }
2771
2772 void validateAnnotationType(DiagnosticPosition pos, Type type) {
2773 if (type.isPrimitive()) return;
2774 if (types.isSameType(type, syms.stringType)) return;
2775 if ((type.tsym.flags() & Flags.ENUM) != 0) return;
2776 if ((type.tsym.flags() & Flags.ANNOTATION) != 0) return;
2777 if (types.cvarLowerBound(type).tsym == syms.classType.tsym) return;
2778 if (types.isArray(type) && !types.isArray(types.elemtype(type))) {
2779 validateAnnotationType(pos, types.elemtype(type));
2780 return;
2781 }
2782 log.error(pos, "invalid.annotation.member.type");
2783 }
2784
2785 /**
2786 * "It is also a compile-time error if any method declared in an
2787 * annotation type has a signature that is override-equivalent to
2788 * that of any public or protected method declared in class Object
2789 * or in the interface annotation.Annotation."
2790 *
2791 * @jls 9.6 Annotation Types
2792 */
2793 void validateAnnotationMethod(DiagnosticPosition pos, MethodSymbol m) {
2794 for (Type sup = syms.annotationType; sup.hasTag(CLASS); sup = types.supertype(sup)) {
2795 Scope s = sup.tsym.members();
2796 for (Symbol sym : s.getSymbolsByName(m.name)) {
2797 if (sym.kind == MTH &&
2798 (sym.flags() & (PUBLIC | PROTECTED)) != 0 &&
2799 types.overrideEquivalent(m.type, sym.type))
2800 log.error(pos, "intf.annotation.member.clash", sym, sup);
2801 }
2802 }
2803 }
2804
2805 /** Check the annotations of a symbol.
2806 */
2807 public void validateAnnotations(List<JCAnnotation> annotations, Symbol s) {
2808 for (JCAnnotation a : annotations)
2809 validateAnnotation(a, s);
2810 }
2811
2812 /** Check the type annotations.
2813 */
2814 public void validateTypeAnnotations(List<JCAnnotation> annotations, boolean isTypeParameter) {
2815 for (JCAnnotation a : annotations)
2816 validateTypeAnnotation(a, isTypeParameter);
2817 }
2818
2819 /** Check an annotation of a symbol.
2820 */
2821 private void validateAnnotation(JCAnnotation a, Symbol s) {
2822 validateAnnotationTree(a);
2823
2824 if (!annotationApplicable(a, s))
2825 log.error(a.pos(), "annotation.type.not.applicable");
2826
2827 if (a.annotationType.type.tsym == syms.functionalInterfaceType.tsym) {
2828 if (s.kind != TYP) {
2829 log.error(a.pos(), "bad.functional.intf.anno");
2830 } else if (!s.isInterface() || (s.flags() & ANNOTATION) != 0) {
2831 log.error(a.pos(), "bad.functional.intf.anno.1", diags.fragment("not.a.functional.intf", s));
2832 }
2833 }
2834 }
2835
2836 public void validateTypeAnnotation(JCAnnotation a, boolean isTypeParameter) {
2837 Assert.checkNonNull(a.type);
2838 validateAnnotationTree(a);
2839
2840 if (a.hasTag(TYPE_ANNOTATION) &&
2841 !a.annotationType.type.isErroneous() &&
2842 !isTypeAnnotation(a, isTypeParameter)) {
2843 log.error(a.pos(), Errors.AnnotationTypeNotApplicableToType(a.type));
2844 }
2845 }
2846
2847 /**
2848 * Validate the proposed container 'repeatable' on the
2849 * annotation type symbol 's'. Report errors at position
2850 * 'pos'.
2851 *
2852 * @param s The (annotation)type declaration annotated with a @Repeatable
2853 * @param repeatable the @Repeatable on 's'
2854 * @param pos where to report errors
2855 */
2856 public void validateRepeatable(TypeSymbol s, Attribute.Compound repeatable, DiagnosticPosition pos) {
2857 Assert.check(types.isSameType(repeatable.type, syms.repeatableType));
2858
2859 Type t = null;
2860 List<Pair<MethodSymbol,Attribute>> l = repeatable.values;
2861 if (!l.isEmpty()) {
2862 Assert.check(l.head.fst.name == names.value);
2863 t = ((Attribute.Class)l.head.snd).getValue();
2864 }
2865
2866 if (t == null) {
2867 // errors should already have been reported during Annotate
2868 return;
2869 }
2870
2871 validateValue(t.tsym, s, pos);
2872 validateRetention(t.tsym, s, pos);
2873 validateDocumented(t.tsym, s, pos);
2874 validateInherited(t.tsym, s, pos);
2875 validateTarget(t.tsym, s, pos);
2876 validateDefault(t.tsym, pos);
2877 }
2878
2879 private void validateValue(TypeSymbol container, TypeSymbol contained, DiagnosticPosition pos) {
2880 Symbol sym = container.members().findFirst(names.value);
2881 if (sym != null && sym.kind == MTH) {
2882 MethodSymbol m = (MethodSymbol) sym;
2883 Type ret = m.getReturnType();
2884 if (!(ret.hasTag(ARRAY) && types.isSameType(((ArrayType)ret).elemtype, contained.type))) {
2885 log.error(pos, "invalid.repeatable.annotation.value.return",
2886 container, ret, types.makeArrayType(contained.type));
2887 }
2888 } else {
2889 log.error(pos, "invalid.repeatable.annotation.no.value", container);
2890 }
2891 }
2892
2893 private void validateRetention(TypeSymbol container, TypeSymbol contained, DiagnosticPosition pos) {
2894 Attribute.RetentionPolicy containerRetention = types.getRetention(container);
2895 Attribute.RetentionPolicy containedRetention = types.getRetention(contained);
2896
2897 boolean error = false;
2898 switch (containedRetention) {
2899 case RUNTIME:
2900 if (containerRetention != Attribute.RetentionPolicy.RUNTIME) {
2901 error = true;
2902 }
2903 break;
2904 case CLASS:
2905 if (containerRetention == Attribute.RetentionPolicy.SOURCE) {
2906 error = true;
2907 }
2908 }
2909 if (error ) {
2910 log.error(pos, "invalid.repeatable.annotation.retention",
2911 container, containerRetention,
2912 contained, containedRetention);
2913 }
2914 }
2915
2916 private void validateDocumented(Symbol container, Symbol contained, DiagnosticPosition pos) {
2917 if (contained.attribute(syms.documentedType.tsym) != null) {
2918 if (container.attribute(syms.documentedType.tsym) == null) {
2919 log.error(pos, "invalid.repeatable.annotation.not.documented", container, contained);
2920 }
2921 }
2922 }
2923
2924 private void validateInherited(Symbol container, Symbol contained, DiagnosticPosition pos) {
2925 if (contained.attribute(syms.inheritedType.tsym) != null) {
2926 if (container.attribute(syms.inheritedType.tsym) == null) {
2927 log.error(pos, "invalid.repeatable.annotation.not.inherited", container, contained);
2928 }
2929 }
2930 }
2931
2932 private void validateTarget(TypeSymbol container, TypeSymbol contained, DiagnosticPosition pos) {
2933 // The set of targets the container is applicable to must be a subset
2934 // (with respect to annotation target semantics) of the set of targets
2935 // the contained is applicable to. The target sets may be implicit or
2936 // explicit.
2937
2938 Set<Name> containerTargets;
2939 Attribute.Array containerTarget = getAttributeTargetAttribute(container);
2940 if (containerTarget == null) {
2941 containerTargets = getDefaultTargetSet();
2942 } else {
2943 containerTargets = new HashSet<>();
2944 for (Attribute app : containerTarget.values) {
2945 if (!(app instanceof Attribute.Enum)) {
2946 continue; // recovery
2947 }
2948 Attribute.Enum e = (Attribute.Enum)app;
2949 containerTargets.add(e.value.name);
2950 }
2951 }
2952
2953 Set<Name> containedTargets;
2954 Attribute.Array containedTarget = getAttributeTargetAttribute(contained);
2955 if (containedTarget == null) {
2956 containedTargets = getDefaultTargetSet();
2957 } else {
2958 containedTargets = new HashSet<>();
2959 for (Attribute app : containedTarget.values) {
2960 if (!(app instanceof Attribute.Enum)) {
2961 continue; // recovery
2962 }
2963 Attribute.Enum e = (Attribute.Enum)app;
2964 containedTargets.add(e.value.name);
2965 }
2966 }
2967
2968 if (!isTargetSubsetOf(containerTargets, containedTargets)) {
2969 log.error(pos, "invalid.repeatable.annotation.incompatible.target", container, contained);
2970 }
2971 }
2972
2973 /* get a set of names for the default target */
2974 private Set<Name> getDefaultTargetSet() {
2975 if (defaultTargets == null) {
2976 Set<Name> targets = new HashSet<>();
2977 targets.add(names.ANNOTATION_TYPE);
2978 targets.add(names.CONSTRUCTOR);
2979 targets.add(names.FIELD);
2980 targets.add(names.LOCAL_VARIABLE);
2981 targets.add(names.METHOD);
2982 targets.add(names.PACKAGE);
2983 targets.add(names.PARAMETER);
2984 targets.add(names.TYPE);
2985
2986 defaultTargets = java.util.Collections.unmodifiableSet(targets);
2987 }
2988
2989 return defaultTargets;
2990 }
2991 private Set<Name> defaultTargets;
2992
2993
2994 /** Checks that s is a subset of t, with respect to ElementType
2995 * semantics, specifically {ANNOTATION_TYPE} is a subset of {TYPE},
2996 * and {TYPE_USE} covers the set {ANNOTATION_TYPE, TYPE, TYPE_USE,
2997 * TYPE_PARAMETER}.
2998 */
2999 private boolean isTargetSubsetOf(Set<Name> s, Set<Name> t) {
3000 // Check that all elements in s are present in t
3001 for (Name n2 : s) {
3002 boolean currentElementOk = false;
3003 for (Name n1 : t) {
3004 if (n1 == n2) {
3005 currentElementOk = true;
3006 break;
3007 } else if (n1 == names.TYPE && n2 == names.ANNOTATION_TYPE) {
3008 currentElementOk = true;
3009 break;
3010 } else if (n1 == names.TYPE_USE &&
3011 (n2 == names.TYPE ||
3012 n2 == names.ANNOTATION_TYPE ||
3013 n2 == names.TYPE_PARAMETER)) {
3014 currentElementOk = true;
3015 break;
3016 }
3017 }
3018 if (!currentElementOk)
3019 return false;
3020 }
3021 return true;
3022 }
3023
3024 private void validateDefault(Symbol container, DiagnosticPosition pos) {
3025 // validate that all other elements of containing type has defaults
3026 Scope scope = container.members();
3027 for(Symbol elm : scope.getSymbols()) {
3028 if (elm.name != names.value &&
3029 elm.kind == MTH &&
3030 ((MethodSymbol)elm).defaultValue == null) {
3031 log.error(pos,
3032 "invalid.repeatable.annotation.elem.nondefault",
3033 container,
3034 elm);
3035 }
3036 }
3037 }
3038
3039 /** Is s a method symbol that overrides a method in a superclass? */
3040 boolean isOverrider(Symbol s) {
3041 if (s.kind != MTH || s.isStatic())
3042 return false;
3043 MethodSymbol m = (MethodSymbol)s;
3044 TypeSymbol owner = (TypeSymbol)m.owner;
3045 for (Type sup : types.closure(owner.type)) {
3046 if (sup == owner.type)
3047 continue; // skip "this"
3048 Scope scope = sup.tsym.members();
3049 for (Symbol sym : scope.getSymbolsByName(m.name)) {
3050 if (!sym.isStatic() && m.overrides(sym, owner, types, true))
3051 return true;
3052 }
3053 }
3054 return false;
3055 }
3056
3057 /** Is the annotation applicable to types? */
3058 protected boolean isTypeAnnotation(JCAnnotation a, boolean isTypeParameter) {
3059 List<Attribute> targets = typeAnnotations.annotationTargets(a.annotationType.type.tsym);
3060 return (targets == null) ?
3061 false :
3062 targets.stream()
3063 .anyMatch(attr -> isTypeAnnotation(attr, isTypeParameter));
3064 }
3065 //where
3066 boolean isTypeAnnotation(Attribute a, boolean isTypeParameter) {
3067 Attribute.Enum e = (Attribute.Enum)a;
3068 return (e.value.name == names.TYPE_USE ||
3069 (isTypeParameter && e.value.name == names.TYPE_PARAMETER));
3070 }
3071
3072 /** Is the annotation applicable to the symbol? */
3073 boolean annotationApplicable(JCAnnotation a, Symbol s) {
3074 Attribute.Array arr = getAttributeTargetAttribute(a.annotationType.type.tsym);
3075 Name[] targets;
3076
3077 if (arr == null) {
3078 targets = defaultTargetMetaInfo(a, s);
3079 } else {
3080 // TODO: can we optimize this?
3081 targets = new Name[arr.values.length];
3082 for (int i=0; i<arr.values.length; ++i) {
3083 Attribute app = arr.values[i];
3084 if (!(app instanceof Attribute.Enum)) {
3085 return true; // recovery
3086 }
3087 Attribute.Enum e = (Attribute.Enum) app;
3088 targets[i] = e.value.name;
3089 }
3090 }
3091 for (Name target : targets) {
3092 if (target == names.TYPE) {
3093 if (s.kind == TYP)
3094 return true;
3095 } else if (target == names.FIELD) {
3096 if (s.kind == VAR && s.owner.kind != MTH)
3097 return true;
3098 } else if (target == names.METHOD) {
3099 if (s.kind == MTH && !s.isConstructor())
3100 return true;
3101 } else if (target == names.PARAMETER) {
3102 if (s.kind == VAR && s.owner.kind == MTH &&
3103 (s.flags() & PARAMETER) != 0) {
3104 return true;
3105 }
3106 } else if (target == names.CONSTRUCTOR) {
3107 if (s.kind == MTH && s.isConstructor())
3108 return true;
3109 } else if (target == names.LOCAL_VARIABLE) {
3110 if (s.kind == VAR && s.owner.kind == MTH &&
3111 (s.flags() & PARAMETER) == 0) {
3112 return true;
3113 }
3114 } else if (target == names.ANNOTATION_TYPE) {
3115 if (s.kind == TYP && (s.flags() & ANNOTATION) != 0) {
3116 return true;
3117 }
3118 } else if (target == names.PACKAGE) {
3119 if (s.kind == PCK)
3120 return true;
3121 } else if (target == names.TYPE_USE) {
3122 if (s.kind == TYP || s.kind == VAR ||
3123 (s.kind == MTH && !s.isConstructor() &&
3124 !s.type.getReturnType().hasTag(VOID)) ||
3125 (s.kind == MTH && s.isConstructor())) {
3126 return true;
3127 }
3128 } else if (target == names.TYPE_PARAMETER) {
3129 if (s.kind == TYP && s.type.hasTag(TYPEVAR))
3130 return true;
3131 } else
3132 return true; // Unknown ElementType. This should be an error at declaration site,
3133 // assume applicable.
3134 }
3135 return false;
3136 }
3137
3138
3139 Attribute.Array getAttributeTargetAttribute(TypeSymbol s) {
3140 Attribute.Compound atTarget = s.getAnnotationTypeMetadata().getTarget();
3141 if (atTarget == null) return null; // ok, is applicable
3142 Attribute atValue = atTarget.member(names.value);
3143 if (!(atValue instanceof Attribute.Array)) return null; // error recovery
3144 return (Attribute.Array) atValue;
3145 }
3146
3147 private final Name[] dfltTargetMeta;
3148 private Name[] defaultTargetMetaInfo(JCAnnotation a, Symbol s) {
3149 return dfltTargetMeta;
3150 }
3151
3152 /** Check an annotation value.
3153 *
3154 * @param a The annotation tree to check
3155 * @return true if this annotation tree is valid, otherwise false
3156 */
3157 public boolean validateAnnotationDeferErrors(JCAnnotation a) {
3158 boolean res = false;
3159 final Log.DiagnosticHandler diagHandler = new Log.DiscardDiagnosticHandler(log);
3160 try {
3161 res = validateAnnotation(a);
3162 } finally {
3163 log.popDiagnosticHandler(diagHandler);
3164 }
3165 return res;
3166 }
3167
3168 private boolean validateAnnotation(JCAnnotation a) {
3169 boolean isValid = true;
3170 AnnotationTypeMetadata metadata = a.annotationType.type.tsym.getAnnotationTypeMetadata();
3171
3172 // collect an inventory of the annotation elements
3173 Set<MethodSymbol> elements = metadata.getAnnotationElements();
3174
3175 // remove the ones that are assigned values
3176 for (JCTree arg : a.args) {
3177 if (!arg.hasTag(ASSIGN)) continue; // recovery
3178 JCAssign assign = (JCAssign)arg;
3179 Symbol m = TreeInfo.symbol(assign.lhs);
3180 if (m == null || m.type.isErroneous()) continue;
3181 if (!elements.remove(m)) {
3182 isValid = false;
3183 log.error(assign.lhs.pos(), "duplicate.annotation.member.value",
3184 m.name, a.type);
3185 }
3186 }
3187
3188 // all the remaining ones better have default values
3189 List<Name> missingDefaults = List.nil();
3190 Set<MethodSymbol> membersWithDefault = metadata.getAnnotationElementsWithDefault();
3191 for (MethodSymbol m : elements) {
3192 if (m.type.isErroneous())
3193 continue;
3194
3195 if (!membersWithDefault.contains(m))
3196 missingDefaults = missingDefaults.append(m.name);
3197 }
3198 missingDefaults = missingDefaults.reverse();
3199 if (missingDefaults.nonEmpty()) {
3200 isValid = false;
3201 String key = (missingDefaults.size() > 1)
3202 ? "annotation.missing.default.value.1"
3203 : "annotation.missing.default.value";
3204 log.error(a.pos(), key, a.type, missingDefaults);
3205 }
3206
3207 return isValid && validateTargetAnnotationValue(a);
3208 }
3209
3210 /* Validate the special java.lang.annotation.Target annotation */
3211 boolean validateTargetAnnotationValue(JCAnnotation a) {
3212 // special case: java.lang.annotation.Target must not have
3213 // repeated values in its value member
3214 if (a.annotationType.type.tsym != syms.annotationTargetType.tsym ||
3215 a.args.tail == null)
3216 return true;
3217
3218 boolean isValid = true;
3219 if (!a.args.head.hasTag(ASSIGN)) return false; // error recovery
3220 JCAssign assign = (JCAssign) a.args.head;
3221 Symbol m = TreeInfo.symbol(assign.lhs);
3222 if (m.name != names.value) return false;
3223 JCTree rhs = assign.rhs;
3224 if (!rhs.hasTag(NEWARRAY)) return false;
3225 JCNewArray na = (JCNewArray) rhs;
3226 Set<Symbol> targets = new HashSet<>();
3227 for (JCTree elem : na.elems) {
3228 if (!targets.add(TreeInfo.symbol(elem))) {
3229 isValid = false;
3230 log.error(elem.pos(), "repeated.annotation.target");
3231 }
3232 }
3233 return isValid;
3234 }
3235
3236 void checkDeprecatedAnnotation(DiagnosticPosition pos, Symbol s) {
3237 if (lint.isEnabled(LintCategory.DEP_ANN) && s.isDeprecatableViaAnnotation() &&
3238 (s.flags() & DEPRECATED) != 0 &&
3239 !syms.deprecatedType.isErroneous() &&
3240 s.attribute(syms.deprecatedType.tsym) == null) {
3241 log.warning(LintCategory.DEP_ANN,
3242 pos, "missing.deprecated.annotation");
3243 }
3244 // Note: @Deprecated has no effect on local variables, parameters and package decls.
3245 if (lint.isEnabled(LintCategory.DEPRECATION) && !s.isDeprecatableViaAnnotation()) {
3246 if (!syms.deprecatedType.isErroneous() && s.attribute(syms.deprecatedType.tsym) != null) {
3247 log.warning(LintCategory.DEPRECATION, pos,
3248 "deprecated.annotation.has.no.effect", Kinds.kindName(s));
3249 }
3250 }
3251 }
3252
3253 void checkDeprecated(final DiagnosticPosition pos, final Symbol other, final Symbol s) {
3254 if ( (s.isDeprecatedForRemoval()
3255 || s.isDeprecated() && !other.isDeprecated())
3256 && (s.outermostClass() != other.outermostClass() || s.outermostClass() == null)) {
3257 deferredLintHandler.report(new DeferredLintHandler.LintLogger() {
3258 @Override
3259 public void report() {
3260 warnDeprecated(pos, s);
3261 }
3262 });
3263 }
3264 }
3265
3266 void checkSunAPI(final DiagnosticPosition pos, final Symbol s) {
3267 if ((s.flags() & PROPRIETARY) != 0) {
3268 deferredLintHandler.report(() -> {
3269 log.mandatoryWarning(pos, "sun.proprietary", s);
3270 });
3271 }
3272 }
3273
3274 void checkProfile(final DiagnosticPosition pos, final Symbol s) {
3275 if (profile != Profile.DEFAULT && (s.flags() & NOT_IN_PROFILE) != 0) {
3276 log.error(pos, "not.in.profile", s, profile);
3277 }
3278 }
3279
3280 /* *************************************************************************
3281 * Check for recursive annotation elements.
3282 **************************************************************************/
3283
3284 /** Check for cycles in the graph of annotation elements.
3285 */
3286 void checkNonCyclicElements(JCClassDecl tree) {
3287 if ((tree.sym.flags_field & ANNOTATION) == 0) return;
3288 Assert.check((tree.sym.flags_field & LOCKED) == 0);
3289 try {
3290 tree.sym.flags_field |= LOCKED;
3291 for (JCTree def : tree.defs) {
3292 if (!def.hasTag(METHODDEF)) continue;
3293 JCMethodDecl meth = (JCMethodDecl)def;
3294 checkAnnotationResType(meth.pos(), meth.restype.type);
3295 }
3296 } finally {
3297 tree.sym.flags_field &= ~LOCKED;
3298 tree.sym.flags_field |= ACYCLIC_ANN;
3299 }
3300 }
3301
3302 void checkNonCyclicElementsInternal(DiagnosticPosition pos, TypeSymbol tsym) {
3303 if ((tsym.flags_field & ACYCLIC_ANN) != 0)
3304 return;
3305 if ((tsym.flags_field & LOCKED) != 0) {
3306 log.error(pos, "cyclic.annotation.element");
3307 return;
3308 }
3309 try {
3310 tsym.flags_field |= LOCKED;
3311 for (Symbol s : tsym.members().getSymbols(NON_RECURSIVE)) {
3312 if (s.kind != MTH)
3313 continue;
3314 checkAnnotationResType(pos, ((MethodSymbol)s).type.getReturnType());
3315 }
3316 } finally {
3317 tsym.flags_field &= ~LOCKED;
3318 tsym.flags_field |= ACYCLIC_ANN;
3319 }
3320 }
3321
3322 void checkAnnotationResType(DiagnosticPosition pos, Type type) {
3323 switch (type.getTag()) {
3324 case CLASS:
3325 if ((type.tsym.flags() & ANNOTATION) != 0)
3326 checkNonCyclicElementsInternal(pos, type.tsym);
3327 break;
3328 case ARRAY:
3329 checkAnnotationResType(pos, types.elemtype(type));
3330 break;
3331 default:
3332 break; // int etc
3333 }
3334 }
3335
3336 /* *************************************************************************
3337 * Check for cycles in the constructor call graph.
3338 **************************************************************************/
3339
3340 /** Check for cycles in the graph of constructors calling other
3341 * constructors.
3342 */
3343 void checkCyclicConstructors(JCClassDecl tree) {
3344 Map<Symbol,Symbol> callMap = new HashMap<>();
3345
3346 // enter each constructor this-call into the map
3347 for (List<JCTree> l = tree.defs; l.nonEmpty(); l = l.tail) {
3348 JCMethodInvocation app = TreeInfo.firstConstructorCall(l.head);
3349 if (app == null) continue;
3350 JCMethodDecl meth = (JCMethodDecl) l.head;
3351 if (TreeInfo.name(app.meth) == names._this) {
3352 callMap.put(meth.sym, TreeInfo.symbol(app.meth));
3353 } else {
3354 meth.sym.flags_field |= ACYCLIC;
3355 }
3356 }
3357
3358 // Check for cycles in the map
3359 Symbol[] ctors = new Symbol[0];
3360 ctors = callMap.keySet().toArray(ctors);
3361 for (Symbol caller : ctors) {
3362 checkCyclicConstructor(tree, caller, callMap);
3363 }
3364 }
3365
3366 /** Look in the map to see if the given constructor is part of a
3367 * call cycle.
3368 */
3369 private void checkCyclicConstructor(JCClassDecl tree, Symbol ctor,
3370 Map<Symbol,Symbol> callMap) {
3371 if (ctor != null && (ctor.flags_field & ACYCLIC) == 0) {
3372 if ((ctor.flags_field & LOCKED) != 0) {
3373 log.error(TreeInfo.diagnosticPositionFor(ctor, tree),
3374 "recursive.ctor.invocation");
3375 } else {
3376 ctor.flags_field |= LOCKED;
3377 checkCyclicConstructor(tree, callMap.remove(ctor), callMap);
3378 ctor.flags_field &= ~LOCKED;
3379 }
3380 ctor.flags_field |= ACYCLIC;
3381 }
3382 }
3383
3384 /* *************************************************************************
3385 * Miscellaneous
3386 **************************************************************************/
3387
3388 /**
3389 * Check for division by integer constant zero
3390 * @param pos Position for error reporting.
3391 * @param operator The operator for the expression
3392 * @param operand The right hand operand for the expression
3393 */
3394 void checkDivZero(final DiagnosticPosition pos, Symbol operator, Type operand) {
3395 if (operand.constValue() != null
3396 && operand.getTag().isSubRangeOf(LONG)
3397 && ((Number) (operand.constValue())).longValue() == 0) {
3398 int opc = ((OperatorSymbol)operator).opcode;
3399 if (opc == ByteCodes.idiv || opc == ByteCodes.imod
3400 || opc == ByteCodes.ldiv || opc == ByteCodes.lmod) {
3401 deferredLintHandler.report(new DeferredLintHandler.LintLogger() {
3402 @Override
3403 public void report() {
3404 warnDivZero(pos);
3405 }
3406 });
3407 }
3408 }
3409 }
3410
3411 /**
3412 * Check for empty statements after if
3413 */
3414 void checkEmptyIf(JCIf tree) {
3415 if (tree.thenpart.hasTag(SKIP) && tree.elsepart == null &&
3416 lint.isEnabled(LintCategory.EMPTY))
3417 log.warning(LintCategory.EMPTY, tree.thenpart.pos(), "empty.if");
3418 }
3419
3420 /** Check that symbol is unique in given scope.
3421 * @param pos Position for error reporting.
3422 * @param sym The symbol.
3423 * @param s The scope.
3424 */
3425 boolean checkUnique(DiagnosticPosition pos, Symbol sym, Scope s) {
3426 if (sym.type.isErroneous())
3427 return true;
3428 if (sym.owner.name == names.any) return false;
3429 for (Symbol byName : s.getSymbolsByName(sym.name, NON_RECURSIVE)) {
3430 if (sym != byName &&
3431 (byName.flags() & CLASH) == 0 &&
3432 sym.kind == byName.kind &&
3433 sym.name != names.error &&
3434 (sym.kind != MTH ||
3435 types.hasSameArgs(sym.type, byName.type) ||
3436 types.hasSameArgs(types.erasure(sym.type), types.erasure(byName.type)))) {
3437 if ((sym.flags() & VARARGS) != (byName.flags() & VARARGS)) {
3438 varargsDuplicateError(pos, sym, byName);
3439 return true;
3440 } else if (sym.kind == MTH && !types.hasSameArgs(sym.type, byName.type, false)) {
3441 duplicateErasureError(pos, sym, byName);
3442 sym.flags_field |= CLASH;
3443 return true;
3444 } else {
3445 duplicateError(pos, byName);
3446 return false;
3447 }
3448 }
3449 }
3450 return true;
3451 }
3452
3453 /** Report duplicate declaration error.
3454 */
3455 void duplicateErasureError(DiagnosticPosition pos, Symbol sym1, Symbol sym2) {
3456 if (!sym1.type.isErroneous() && !sym2.type.isErroneous()) {
3457 log.error(pos, "name.clash.same.erasure", sym1, sym2);
3458 }
3459 }
3460
3461 /**Check that types imported through the ordinary imports don't clash with types imported
3462 * by other (static or ordinary) imports. Note that two static imports may import two clashing
3463 * types without an error on the imports.
3464 * @param toplevel The toplevel tree for which the test should be performed.
3465 */
3466 void checkImportsUnique(JCCompilationUnit toplevel) {
3467 WriteableScope ordinallyImportedSoFar = WriteableScope.create(toplevel.packge);
3468 WriteableScope staticallyImportedSoFar = WriteableScope.create(toplevel.packge);
3469 WriteableScope topLevelScope = toplevel.toplevelScope;
3470
3471 for (JCTree def : toplevel.defs) {
3472 if (!def.hasTag(IMPORT))
3473 continue;
3474
3475 JCImport imp = (JCImport) def;
3476
3477 if (imp.importScope == null)
3478 continue;
3479
3480 for (Symbol sym : imp.importScope.getSymbols(sym -> sym.kind == TYP)) {
3481 if (imp.isStatic()) {
3482 checkUniqueImport(imp.pos(), ordinallyImportedSoFar, staticallyImportedSoFar, topLevelScope, sym, true);
3483 staticallyImportedSoFar.enter(sym);
3484 } else {
3485 checkUniqueImport(imp.pos(), ordinallyImportedSoFar, staticallyImportedSoFar, topLevelScope, sym, false);
3486 ordinallyImportedSoFar.enter(sym);
3487 }
3488 }
3489
3490 imp.importScope = null;
3491 }
3492 }
3493
3494 /** Check that single-type import is not already imported or top-level defined,
3495 * but make an exception for two single-type imports which denote the same type.
3496 * @param pos Position for error reporting.
3497 * @param ordinallyImportedSoFar A Scope containing types imported so far through
3498 * ordinary imports.
3499 * @param staticallyImportedSoFar A Scope containing types imported so far through
3500 * static imports.
3501 * @param topLevelScope The current file's top-level Scope
3502 * @param sym The symbol.
3503 * @param staticImport Whether or not this was a static import
3504 */
3505 private boolean checkUniqueImport(DiagnosticPosition pos, Scope ordinallyImportedSoFar,
3506 Scope staticallyImportedSoFar, Scope topLevelScope,
3507 Symbol sym, boolean staticImport) {
3508 Filter<Symbol> duplicates = candidate -> candidate != sym && !candidate.type.isErroneous();
3509 Symbol clashing = ordinallyImportedSoFar.findFirst(sym.name, duplicates);
3510 if (clashing == null && !staticImport) {
3511 clashing = staticallyImportedSoFar.findFirst(sym.name, duplicates);
3512 }
3513 if (clashing != null) {
3514 if (staticImport)
3515 log.error(pos, "already.defined.static.single.import", clashing);
3516 else
3517 log.error(pos, "already.defined.single.import", clashing);
3518 return false;
3519 }
3520 clashing = topLevelScope.findFirst(sym.name, duplicates);
3521 if (clashing != null) {
3522 log.error(pos, "already.defined.this.unit", clashing);
3523 return false;
3524 }
3525 return true;
3526 }
3527
3528 /** Check that a qualified name is in canonical form (for import decls).
3529 */
3530 public void checkCanonical(JCTree tree) {
3531 if (!isCanonical(tree))
3532 log.error(tree.pos(), "import.requires.canonical",
3533 TreeInfo.symbol(tree));
3534 }
3535 // where
3536 private boolean isCanonical(JCTree tree) {
3537 while (tree.hasTag(SELECT)) {
3538 JCFieldAccess s = (JCFieldAccess) tree;
3539 if (s.sym.owner.name != TreeInfo.symbol(s.selected).name)
3540 return false;
3541 tree = s.selected;
3542 }
3543 return true;
3544 }
3545
3546 /** Check that an auxiliary class is not accessed from any other file than its own.
3547 */
3548 void checkForBadAuxiliaryClassAccess(DiagnosticPosition pos, Env<AttrContext> env, ClassSymbol c) {
3549 if (lint.isEnabled(Lint.LintCategory.AUXILIARYCLASS) &&
3550 (c.flags() & AUXILIARY) != 0 &&
3551 rs.isAccessible(env, c) &&
3552 !fileManager.isSameFile(c.sourcefile, env.toplevel.sourcefile))
3553 {
3554 log.warning(pos, "auxiliary.class.accessed.from.outside.of.its.source.file",
3555 c, c.sourcefile);
3556 }
3557 }
3558
3559 private class ConversionWarner extends Warner {
3560 final String uncheckedKey;
3561 final Type found;
3562 final Type expected;
3563 public ConversionWarner(DiagnosticPosition pos, String uncheckedKey, Type found, Type expected) {
3564 super(pos);
3565 this.uncheckedKey = uncheckedKey;
3566 this.found = found;
3567 this.expected = expected;
3568 }
3569
3570 @Override
3571 public void warn(LintCategory lint) {
3572 boolean warned = this.warned;
3573 super.warn(lint);
3574 if (warned) return; // suppress redundant diagnostics
3575 switch (lint) {
3576 case UNCHECKED:
3577 Check.this.warnUnchecked(pos(), "prob.found.req", diags.fragment(uncheckedKey), found, expected);
3578 break;
3579 case VARARGS:
3580 if (method != null &&
3581 method.attribute(syms.trustMeType.tsym) != null &&
3582 isTrustMeAllowedOnMethod(method) &&
3583 !types.isReifiable(method.type.getParameterTypes().last())) {
3584 Check.this.warnUnsafeVararg(pos(), "varargs.unsafe.use.varargs.param", method.params.last());
3585 }
3586 break;
3587 default:
3588 throw new AssertionError("Unexpected lint: " + lint);
3589 }
3590 }
3591 }
3592
3593 public Warner castWarner(DiagnosticPosition pos, Type found, Type expected) {
3594 return new ConversionWarner(pos, "unchecked.cast.to.type", found, expected);
3595 }
3596
3597 public Warner convertWarner(DiagnosticPosition pos, Type found, Type expected) {
3598 return new ConversionWarner(pos, "unchecked.assign", found, expected);
3599 }
3600
3601 public void checkFunctionalInterface(JCClassDecl tree, ClassSymbol cs) {
3602 Compound functionalType = cs.attribute(syms.functionalInterfaceType.tsym);
3603
3604 if (functionalType != null) {
3605 try {
3606 types.findDescriptorSymbol((TypeSymbol)cs);
3607 } catch (Types.FunctionDescriptorLookupError ex) {
3608 DiagnosticPosition pos = tree.pos();
3609 for (JCAnnotation a : tree.getModifiers().annotations) {
3610 if (a.annotationType.type.tsym == syms.functionalInterfaceType.tsym) {
3611 pos = a.pos();
3612 break;
3613 }
3614 }
3615 log.error(pos, "bad.functional.intf.anno.1", ex.getDiagnostic());
3616 }
3617 }
3618 }
3619
3620 public void checkImportsResolvable(final JCCompilationUnit toplevel) {
3621 for (final JCImport imp : toplevel.getImports()) {
3622 if (!imp.staticImport || !imp.qualid.hasTag(SELECT))
3623 continue;
3624 final JCFieldAccess select = (JCFieldAccess) imp.qualid;
3625 final Symbol origin;
3626 if (select.name == names.asterisk || (origin = TreeInfo.symbol(select.selected)) == null || origin.kind != TYP)
3627 continue;
3628
3629 TypeSymbol site = (TypeSymbol) TreeInfo.symbol(select.selected);
3630 if (!checkTypeContainsImportableElement(site, site, toplevel.packge, select.name, new HashSet<Symbol>())) {
3631 log.error(imp.pos(), "cant.resolve.location",
3632 KindName.STATIC,
3633 select.name, List.<Type>nil(), List.<Type>nil(),
3634 Kinds.typeKindName(TreeInfo.symbol(select.selected).type),
3635 TreeInfo.symbol(select.selected).type);
3636 }
3637 }
3638 }
3639
3640 // Check that packages imported are in scope (JLS 7.4.3, 6.3, 6.5.3.1, 6.5.3.2)
3641 public void checkImportedPackagesObservable(final JCCompilationUnit toplevel) {
3642 OUTER: for (JCImport imp : toplevel.getImports()) {
3643 if (!imp.staticImport && TreeInfo.name(imp.qualid) == names.asterisk) {
3644 TypeSymbol tsym = ((JCFieldAccess)imp.qualid).selected.type.tsym;
3645 if (toplevel.modle.visiblePackages != null) {
3646 //TODO - unclear: selects like javax.* will get resolved from the current module
3647 //(as javax is not an exported package from any module). And as javax in the current
3648 //module typically does not contain any classes or subpackages, we need to go through
3649 //the visible packages to find a sub-package:
3650 for (PackageSymbol known : toplevel.modle.visiblePackages.values()) {
3651 if (Convert.packagePart(known.fullname) == tsym.flatName())
3652 continue OUTER;
3653 }
3654 }
3655 if (tsym.kind == PCK && tsym.members().isEmpty() && !tsym.exists()) {
3656 log.error(DiagnosticFlag.RESOLVE_ERROR, imp.pos, "doesnt.exist", tsym);
3657 }
3658 }
3659 }
3660 }
3661
3662 private boolean checkTypeContainsImportableElement(TypeSymbol tsym, TypeSymbol origin, PackageSymbol packge, Name name, Set<Symbol> processed) {
3663 if (tsym == null || !processed.add(tsym))
3664 return false;
3665
3666 // also search through inherited names
3667 if (checkTypeContainsImportableElement(types.supertype(tsym.type).tsym, origin, packge, name, processed))
3668 return true;
3669
3670 for (Type t : types.interfaces(tsym.type))
3671 if (checkTypeContainsImportableElement(t.tsym, origin, packge, name, processed))
3672 return true;
3673
3674 for (Symbol sym : tsym.members().getSymbolsByName(name)) {
3675 if (sym.isStatic() &&
3676 importAccessible(sym, packge) &&
3677 sym.isMemberOf(origin, types)) {
3678 return true;
3679 }
3680 }
3681
3682 return false;
3683 }
3684
3685 // is the sym accessible everywhere in packge?
3686 public boolean importAccessible(Symbol sym, PackageSymbol packge) {
3687 try {
3688 int flags = (int)(sym.flags() & AccessFlags);
3689 switch (flags) {
3690 default:
3691 case PUBLIC:
3692 return true;
3693 case PRIVATE:
3694 return false;
3695 case 0:
3696 case PROTECTED:
3697 return sym.packge() == packge;
3698 }
3699 } catch (ClassFinder.BadClassFile err) {
3700 throw err;
3701 } catch (CompletionFailure ex) {
3702 return false;
3703 }
3704 }
3705
3706 public void checkLeaksNotAccessible(Env<AttrContext> env, JCClassDecl check) {
3707 JCCompilationUnit toplevel = env.toplevel;
3708
3709 if ( toplevel.modle == syms.unnamedModule
3710 || toplevel.modle == syms.noModule
3711 || (check.sym.flags() & COMPOUND) != 0) {
3712 return ;
3713 }
3714
3715 ExportsDirective currentExport = findExport(toplevel.packge);
3716
3717 if ( currentExport == null //not exported
3718 || currentExport.modules != null) //don't check classes in qualified export
3719 return ;
3720
3721 new TreeScanner() {
3722 Lint lint = env.info.lint;
3723 boolean inSuperType;
3724
3725 @Override
3726 public void visitBlock(JCBlock tree) {
3727 }
3728 @Override
3729 public void visitMethodDef(JCMethodDecl tree) {
3730 if (!isAPISymbol(tree.sym))
3731 return;
3732 Lint prevLint = lint;
3733 try {
3734 lint = lint.augment(tree.sym);
3735 if (lint.isEnabled(LintCategory.EXPORTS)) {
3736 super.visitMethodDef(tree);
3737 }
3738 } finally {
3739 lint = prevLint;
3740 }
3741 }
3742 @Override
3743 public void visitVarDef(JCVariableDecl tree) {
3744 if (!isAPISymbol(tree.sym) && tree.sym.owner.kind != MTH)
3745 return;
3746 Lint prevLint = lint;
3747 try {
3748 lint = lint.augment(tree.sym);
3749 if (lint.isEnabled(LintCategory.EXPORTS)) {
3750 scan(tree.mods);
3751 scan(tree.vartype);
3752 }
3753 } finally {
3754 lint = prevLint;
3755 }
3756 }
3757 @Override
3758 public void visitClassDef(JCClassDecl tree) {
3759 if (tree != check)
3760 return ;
3761
3762 if (!isAPISymbol(tree.sym))
3763 return ;
3764
3765 Lint prevLint = lint;
3766 try {
3767 lint = lint.augment(tree.sym);
3768 if (lint.isEnabled(LintCategory.EXPORTS)) {
3769 scan(tree.mods);
3770 scan(tree.typarams);
3771 try {
3772 inSuperType = true;
3773 scan(tree.extending);
3774 scan(tree.implementing);
3775 } finally {
3776 inSuperType = false;
3777 }
3778 scan(tree.defs);
3779 }
3780 } finally {
3781 lint = prevLint;
3782 }
3783 }
3784 @Override
3785 public void visitTypeApply(JCTypeApply tree) {
3786 scan(tree.clazz);
3787 boolean oldInSuperType = inSuperType;
3788 try {
3789 inSuperType = false;
3790 scan(tree.arguments);
3791 } finally {
3792 inSuperType = oldInSuperType;
3793 }
3794 }
3795 @Override
3796 public void visitIdent(JCIdent tree) {
3797 Symbol sym = TreeInfo.symbol(tree);
3798 if (sym.kind == TYP && !sym.type.hasTag(TYPEVAR)) {
3799 checkVisible(tree.pos(), sym, toplevel.packge, inSuperType);
3800 }
3801 }
3802
3803 @Override
3804 public void visitSelect(JCFieldAccess tree) {
3805 Symbol sym = TreeInfo.symbol(tree);
3806 Symbol sitesym = TreeInfo.symbol(tree.selected);
3807 if (sym.kind == TYP && sitesym.kind == PCK) {
3808 checkVisible(tree.pos(), sym, toplevel.packge, inSuperType);
3809 } else {
3810 super.visitSelect(tree);
3811 }
3812 }
3813
3814 @Override
3815 public void visitAnnotation(JCAnnotation tree) {
3816 if (tree.attribute.type.tsym.getAnnotation(java.lang.annotation.Documented.class) != null)
3817 super.visitAnnotation(tree);
3818 }
3819
3820 }.scan(check);
3821 }
3822 //where:
3823 private ExportsDirective findExport(PackageSymbol pack) {
3824 for (ExportsDirective d : pack.modle.exports) {
3825 if (d.packge == pack)
3826 return d;
3827 }
3828
3829 return null;
3830 }
3831 private boolean isAPISymbol(Symbol sym) {
3832 while (sym.kind != PCK) {
3833 if ((sym.flags() & Flags.PUBLIC) == 0 && (sym.flags() & Flags.PROTECTED) == 0) {
3834 return false;
3835 }
3836 sym = sym.owner;
3837 }
3838 return true;
3839 }
3840 private void checkVisible(DiagnosticPosition pos, Symbol what, PackageSymbol inPackage, boolean inSuperType) {
3841 if (!isAPISymbol(what) && !inSuperType) { //package private/private element
3842 log.warning(LintCategory.EXPORTS, pos, Warnings.LeaksNotAccessible(kindName(what), what, what.packge().modle));
3843 return ;
3844 }
3845
3846 PackageSymbol whatPackage = what.packge();
3847 ExportsDirective whatExport = findExport(whatPackage);
3848 ExportsDirective inExport = findExport(inPackage);
3849
3850 if (whatExport == null) { //package not exported:
3851 log.warning(LintCategory.EXPORTS, pos, Warnings.LeaksNotAccessibleUnexported(kindName(what), what, what.packge().modle));
3852 return ;
3853 }
3854
3855 if (whatExport.modules != null) {
3856 if (inExport.modules == null || !whatExport.modules.containsAll(inExport.modules)) {
3857 log.warning(LintCategory.EXPORTS, pos, Warnings.LeaksNotAccessibleUnexportedQualified(kindName(what), what, what.packge().modle));
3858 }
3859 }
3860
3861 if (whatPackage.modle != inPackage.modle && whatPackage.modle != syms.java_base) {
3862 //check that relativeTo.modle requires transitive what.modle, somehow:
3863 List<ModuleSymbol> todo = List.of(inPackage.modle);
3864
3865 while (todo.nonEmpty()) {
3866 ModuleSymbol current = todo.head;
3867 todo = todo.tail;
3868 if (current == whatPackage.modle)
3869 return ; //OK
3870 for (RequiresDirective req : current.requires) {
3871 if (req.isTransitive()) {
3872 todo = todo.prepend(req.module);
3873 }
3874 }
3875 }
3876
3877 log.warning(LintCategory.EXPORTS, pos, Warnings.LeaksNotAccessibleNotRequiredTransitive(kindName(what), what, what.packge().modle));
3878 }
3879 }
3880 }