1 /*
2 * Copyright (c) 1999, 2022, 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 import java.util.function.BiConsumer;
30 import java.util.function.Predicate;
31 import java.util.function.Supplier;
32
33 import javax.lang.model.element.ElementKind;
34 import javax.lang.model.element.NestingKind;
35 import javax.tools.JavaFileManager;
36
37 import com.sun.source.tree.CaseTree;
38 import com.sun.tools.javac.code.*;
39 import com.sun.tools.javac.code.Attribute.Compound;
40 import com.sun.tools.javac.code.Directive.ExportsDirective;
41 import com.sun.tools.javac.code.Directive.RequiresDirective;
42 import com.sun.tools.javac.code.Source.Feature;
43 import com.sun.tools.javac.comp.Annotate.AnnotationTypeMetadata;
44 import com.sun.tools.javac.jvm.*;
45 import com.sun.tools.javac.resources.CompilerProperties.Errors;
46 import com.sun.tools.javac.resources.CompilerProperties.Fragments;
47 import com.sun.tools.javac.resources.CompilerProperties.Warnings;
48 import com.sun.tools.javac.tree.*;
49 import com.sun.tools.javac.util.*;
50 import com.sun.tools.javac.util.JCDiagnostic.DiagnosticFlag;
51 import com.sun.tools.javac.util.JCDiagnostic.DiagnosticPosition;
52 import com.sun.tools.javac.util.JCDiagnostic.Error;
53 import com.sun.tools.javac.util.JCDiagnostic.Fragment;
54 import com.sun.tools.javac.util.JCDiagnostic.Warning;
55 import com.sun.tools.javac.util.List;
56
57 import com.sun.tools.javac.code.Lint;
58 import com.sun.tools.javac.code.Lint.LintCategory;
59 import com.sun.tools.javac.code.Scope.WriteableScope;
60 import com.sun.tools.javac.code.Type.*;
61 import com.sun.tools.javac.code.Symbol.*;
62 import com.sun.tools.javac.comp.DeferredAttr.DeferredAttrContext;
63 import com.sun.tools.javac.tree.JCTree.*;
64
65 import static com.sun.tools.javac.code.Flags.*;
66 import static com.sun.tools.javac.code.Flags.ANNOTATION;
67 import static com.sun.tools.javac.code.Flags.SYNCHRONIZED;
68 import static com.sun.tools.javac.code.Kinds.*;
69 import static com.sun.tools.javac.code.Kinds.Kind.*;
70 import static com.sun.tools.javac.code.Scope.LookupKind.NON_RECURSIVE;
71 import static com.sun.tools.javac.code.TypeTag.*;
72 import static com.sun.tools.javac.code.TypeTag.WILDCARD;
73
74 import static com.sun.tools.javac.tree.JCTree.Tag.*;
75 import javax.lang.model.element.Element;
76 import javax.lang.model.element.ExecutableElement;
77 import javax.lang.model.element.TypeElement;
78 import javax.lang.model.type.DeclaredType;
79 import javax.lang.model.type.TypeMirror;
80 import javax.lang.model.util.ElementFilter;
81 import javax.lang.model.util.ElementKindVisitor14;
82
83 /** Type checking helper class for the attribution phase.
84 *
85 * <p><b>This is NOT part of any supported API.
86 * If you write code that depends on this, you do so at your own risk.
87 * This code and its internal interfaces are subject to change or
88 * deletion without notice.</b>
89 */
90 public class Check {
91 protected static final Context.Key<Check> checkKey = new Context.Key<>();
92
93 private final Names names;
94 private final Log log;
95 private final Resolve rs;
96 private final Symtab syms;
97 private final Enter enter;
98 private final DeferredAttr deferredAttr;
99 private final Infer infer;
100 private final Types types;
101 private final TypeAnnotations typeAnnotations;
102 private final JCDiagnostic.Factory diags;
103 private final JavaFileManager fileManager;
104 private final Source source;
105 private final Target target;
106 private final Profile profile;
107 private final Preview preview;
108 private final boolean warnOnAnyAccessToMembers;
109
110 // The set of lint options currently in effect. It is initialized
111 // from the context, and then is set/reset as needed by Attr as it
112 // visits all the various parts of the trees during attribution.
113 private Lint lint;
114
115 // The method being analyzed in Attr - it is set/reset as needed by
116 // Attr as it visits new method declarations.
117 private MethodSymbol method;
118
119 public static Check instance(Context context) {
120 Check instance = context.get(checkKey);
121 if (instance == null)
122 instance = new Check(context);
123 return instance;
124 }
125
126 protected Check(Context context) {
127 context.put(checkKey, this);
128
129 names = Names.instance(context);
130 log = Log.instance(context);
131 rs = Resolve.instance(context);
132 syms = Symtab.instance(context);
133 enter = Enter.instance(context);
134 deferredAttr = DeferredAttr.instance(context);
135 infer = Infer.instance(context);
136 types = Types.instance(context);
137 typeAnnotations = TypeAnnotations.instance(context);
138 diags = JCDiagnostic.Factory.instance(context);
139 Options options = Options.instance(context);
140 lint = Lint.instance(context);
141 fileManager = context.get(JavaFileManager.class);
142
143 source = Source.instance(context);
144 target = Target.instance(context);
145 warnOnAnyAccessToMembers = options.isSet("warnOnAccessToMembers");
146 Target target = Target.instance(context);
147 syntheticNameChar = target.syntheticNameChar();
148
149 profile = Profile.instance(context);
150 preview = Preview.instance(context);
151
152 boolean verboseDeprecated = lint.isEnabled(LintCategory.DEPRECATION);
153 boolean verboseRemoval = lint.isEnabled(LintCategory.REMOVAL);
154 boolean verboseUnchecked = lint.isEnabled(LintCategory.UNCHECKED);
155 boolean enforceMandatoryWarnings = true;
156
157 deprecationHandler = new MandatoryWarningHandler(log, null, verboseDeprecated,
158 enforceMandatoryWarnings, "deprecated", LintCategory.DEPRECATION);
159 removalHandler = new MandatoryWarningHandler(log, null, verboseRemoval,
160 enforceMandatoryWarnings, "removal", LintCategory.REMOVAL);
161 uncheckedHandler = new MandatoryWarningHandler(log, null, verboseUnchecked,
162 enforceMandatoryWarnings, "unchecked", LintCategory.UNCHECKED);
163 sunApiHandler = new MandatoryWarningHandler(log, null, false,
164 enforceMandatoryWarnings, "sunapi", null);
165
166 deferredLintHandler = DeferredLintHandler.instance(context);
167
168 allowModules = Feature.MODULES.allowedInSource(source);
169 allowRecords = Feature.RECORDS.allowedInSource(source);
170 allowSealed = Feature.SEALED_CLASSES.allowedInSource(source);
171 }
172
173 /** Character for synthetic names
174 */
175 char syntheticNameChar;
176
177 /** A table mapping flat names of all compiled classes for each module in this run
178 * to their symbols; maintained from outside.
179 */
180 private Map<Pair<ModuleSymbol, Name>,ClassSymbol> compiled = new HashMap<>();
181
182 /** A handler for messages about deprecated usage.
183 */
184 private MandatoryWarningHandler deprecationHandler;
185
186 /** A handler for messages about deprecated-for-removal usage.
187 */
188 private MandatoryWarningHandler removalHandler;
189
190 /** A handler for messages about unchecked or unsafe usage.
191 */
192 private MandatoryWarningHandler uncheckedHandler;
193
194 /** A handler for messages about using proprietary API.
195 */
196 private MandatoryWarningHandler sunApiHandler;
197
198 /** A handler for deferred lint warnings.
199 */
200 private DeferredLintHandler deferredLintHandler;
201
202 /** Are modules allowed
203 */
204 private final boolean allowModules;
205
206 /** Are records allowed
207 */
208 private final boolean allowRecords;
209
210 /** Are sealed classes allowed
211 */
212 private final boolean allowSealed;
213
214 /* *************************************************************************
215 * Errors and Warnings
216 **************************************************************************/
217
218 Lint setLint(Lint newLint) {
219 Lint prev = lint;
220 lint = newLint;
221 return prev;
222 }
223
224 MethodSymbol setMethod(MethodSymbol newMethod) {
225 MethodSymbol prev = method;
226 method = newMethod;
227 return prev;
228 }
229
230 /** Warn about deprecated symbol.
231 * @param pos Position to be used for error reporting.
232 * @param sym The deprecated symbol.
233 */
234 void warnDeprecated(DiagnosticPosition pos, Symbol sym) {
235 if (sym.isDeprecatedForRemoval()) {
236 if (!lint.isSuppressed(LintCategory.REMOVAL)) {
237 if (sym.kind == MDL) {
238 removalHandler.report(pos, Warnings.HasBeenDeprecatedForRemovalModule(sym));
239 } else {
240 removalHandler.report(pos, Warnings.HasBeenDeprecatedForRemoval(sym, sym.location()));
241 }
242 }
243 } else if (!lint.isSuppressed(LintCategory.DEPRECATION)) {
244 if (sym.kind == MDL) {
245 deprecationHandler.report(pos, Warnings.HasBeenDeprecatedModule(sym));
246 } else {
247 deprecationHandler.report(pos, Warnings.HasBeenDeprecated(sym, sym.location()));
248 }
249 }
250 }
251
252 /** Log a preview warning.
253 * @param pos Position to be used for error reporting.
254 * @param msg A Warning describing the problem.
255 */
256 public void warnPreviewAPI(DiagnosticPosition pos, Warning warnKey) {
257 if (!lint.isSuppressed(LintCategory.PREVIEW))
258 preview.reportPreviewWarning(pos, warnKey);
259 }
260
261 /** Log a preview warning.
262 * @param pos Position to be used for error reporting.
263 * @param msg A Warning describing the problem.
264 */
265 public void warnDeclaredUsingPreview(DiagnosticPosition pos, Symbol sym) {
266 if (!lint.isSuppressed(LintCategory.PREVIEW))
267 preview.reportPreviewWarning(pos, Warnings.DeclaredUsingPreview(kindName(sym), sym));
268 }
269
270 /** Warn about unchecked operation.
271 * @param pos Position to be used for error reporting.
272 * @param msg A string describing the problem.
273 */
274 public void warnUnchecked(DiagnosticPosition pos, Warning warnKey) {
275 if (!lint.isSuppressed(LintCategory.UNCHECKED))
276 uncheckedHandler.report(pos, warnKey);
277 }
278
279 /** Warn about unsafe vararg method decl.
280 * @param pos Position to be used for error reporting.
281 */
282 void warnUnsafeVararg(DiagnosticPosition pos, Warning warnKey) {
283 if (lint.isEnabled(LintCategory.VARARGS))
284 log.warning(LintCategory.VARARGS, pos, warnKey);
285 }
286
287 public void warnStatic(DiagnosticPosition pos, Warning warnKey) {
288 if (lint.isEnabled(LintCategory.STATIC))
289 log.warning(LintCategory.STATIC, pos, warnKey);
290 }
291
292 /** Warn about division by integer constant zero.
293 * @param pos Position to be used for error reporting.
294 */
295 void warnDivZero(DiagnosticPosition pos) {
296 if (lint.isEnabled(LintCategory.DIVZERO))
297 log.warning(LintCategory.DIVZERO, pos, Warnings.DivZero);
298 }
299
300 /**
301 * Report any deferred diagnostics.
302 */
303 public void reportDeferredDiagnostics() {
304 deprecationHandler.reportDeferredDiagnostic();
305 removalHandler.reportDeferredDiagnostic();
306 uncheckedHandler.reportDeferredDiagnostic();
307 sunApiHandler.reportDeferredDiagnostic();
308 }
309
310
311 /** Report a failure to complete a class.
312 * @param pos Position to be used for error reporting.
313 * @param ex The failure to report.
314 */
315 public Type completionError(DiagnosticPosition pos, CompletionFailure ex) {
316 log.error(JCDiagnostic.DiagnosticFlag.NON_DEFERRABLE, pos, Errors.CantAccess(ex.sym, ex.getDetailValue()));
317 return syms.errType;
318 }
319
320 /** Report an error that wrong type tag was found.
321 * @param pos Position to be used for error reporting.
322 * @param required An internationalized string describing the type tag
323 * required.
324 * @param found The type that was found.
325 */
326 Type typeTagError(DiagnosticPosition pos, JCDiagnostic required, Object found) {
327 // this error used to be raised by the parser,
328 // but has been delayed to this point:
329 if (found instanceof Type type && type.hasTag(VOID)) {
330 log.error(pos, Errors.IllegalStartOfType);
331 return syms.errType;
332 }
333 log.error(pos, Errors.TypeFoundReq(found, required));
334 return types.createErrorType(found instanceof Type type ? type : syms.errType);
335 }
336
337 /** Report an error that symbol cannot be referenced before super
338 * has been called.
339 * @param pos Position to be used for error reporting.
340 * @param sym The referenced symbol.
341 */
342 void earlyRefError(DiagnosticPosition pos, Symbol sym) {
343 log.error(pos, Errors.CantRefBeforeCtorCalled(sym));
344 }
345
346 /** Report duplicate declaration error.
347 */
348 void duplicateError(DiagnosticPosition pos, Symbol sym) {
349 if (!sym.type.isErroneous()) {
350 Symbol location = sym.location();
351 if (location.kind == MTH &&
352 ((MethodSymbol)location).isStaticOrInstanceInit()) {
353 log.error(pos,
354 Errors.AlreadyDefinedInClinit(kindName(sym),
355 sym,
356 kindName(sym.location()),
357 kindName(sym.location().enclClass()),
358 sym.location().enclClass()));
359 } else {
360 /* dont error if this is a duplicated parameter of a generated canonical constructor
361 * as we should have issued an error for the duplicated fields
362 */
363 if (location.kind != MTH ||
364 ((sym.owner.flags_field & GENERATEDCONSTR) == 0) ||
365 ((sym.owner.flags_field & RECORD) == 0)) {
366 log.error(pos,
367 Errors.AlreadyDefined(kindName(sym),
368 sym,
369 kindName(sym.location()),
370 sym.location()));
371 }
372 }
373 }
374 }
375
376 /** Report array/varargs duplicate declaration
377 */
378 void varargsDuplicateError(DiagnosticPosition pos, Symbol sym1, Symbol sym2) {
379 if (!sym1.type.isErroneous() && !sym2.type.isErroneous()) {
380 log.error(pos, Errors.ArrayAndVarargs(sym1, sym2, sym2.location()));
381 }
382 }
383
384 /* ************************************************************************
385 * duplicate declaration checking
386 *************************************************************************/
387
388 /** Check that variable does not hide variable with same name in
389 * immediately enclosing local scope.
390 * @param pos Position for error reporting.
391 * @param v The symbol.
392 * @param s The scope.
393 */
394 void checkTransparentVar(DiagnosticPosition pos, VarSymbol v, Scope s) {
395 for (Symbol sym : s.getSymbolsByName(v.name)) {
396 if (sym.owner != v.owner) break;
397 if (sym.kind == VAR &&
398 sym.owner.kind.matches(KindSelector.VAL_MTH) &&
399 v.name != names.error) {
400 duplicateError(pos, sym);
401 return;
402 }
403 }
404 }
405
406 /** Check that a class or interface does not hide a class or
407 * interface with same name in immediately enclosing local scope.
408 * @param pos Position for error reporting.
409 * @param c The symbol.
410 * @param s The scope.
411 */
412 void checkTransparentClass(DiagnosticPosition pos, ClassSymbol c, Scope s) {
413 for (Symbol sym : s.getSymbolsByName(c.name)) {
414 if (sym.owner != c.owner) break;
415 if (sym.kind == TYP && !sym.type.hasTag(TYPEVAR) &&
416 sym.owner.kind.matches(KindSelector.VAL_MTH) &&
417 c.name != names.error) {
418 duplicateError(pos, sym);
419 return;
420 }
421 }
422 }
423
424 /** Check that class does not have the same name as one of
425 * its enclosing classes, or as a class defined in its enclosing scope.
426 * return true if class is unique in its enclosing scope.
427 * @param pos Position for error reporting.
428 * @param name The class name.
429 * @param s The enclosing scope.
430 */
431 boolean checkUniqueClassName(DiagnosticPosition pos, Name name, Scope s) {
432 for (Symbol sym : s.getSymbolsByName(name, NON_RECURSIVE)) {
433 if (sym.kind == TYP && sym.name != names.error) {
434 duplicateError(pos, sym);
435 return false;
436 }
437 }
438 for (Symbol sym = s.owner; sym != null; sym = sym.owner) {
439 if (sym.kind == TYP && sym.name == name && sym.name != names.error) {
440 duplicateError(pos, sym);
441 return true;
442 }
443 }
444 return true;
445 }
446
447 /* *************************************************************************
448 * Class name generation
449 **************************************************************************/
450
451
452 private Map<Pair<Name, Name>, Integer> localClassNameIndexes = new HashMap<>();
453
454 /** Return name of local class.
455 * This is of the form {@code <enclClass> $ n <classname> }
456 * where
457 * enclClass is the flat name of the enclosing class,
458 * classname is the simple name of the local class
459 */
460 public Name localClassName(ClassSymbol c) {
461 Name enclFlatname = c.owner.enclClass().flatname;
462 String enclFlatnameStr = enclFlatname.toString();
463 Pair<Name, Name> key = new Pair<>(enclFlatname, c.name);
464 Integer index = localClassNameIndexes.get(key);
465 for (int i = (index == null) ? 1 : index; ; i++) {
466 Name flatname = names.fromString(enclFlatnameStr
467 + syntheticNameChar + i + c.name);
468 if (getCompiled(c.packge().modle, flatname) == null) {
469 localClassNameIndexes.put(key, i + 1);
470 return flatname;
471 }
472 }
473 }
474
475 public void clearLocalClassNameIndexes(ClassSymbol c) {
476 if (c.owner != null && c.owner.kind != NIL) {
477 localClassNameIndexes.remove(new Pair<>(
478 c.owner.enclClass().flatname, c.name));
479 }
480 }
481
482 public void newRound() {
483 compiled.clear();
484 localClassNameIndexes.clear();
485 }
486
487 public void clear() {
488 deprecationHandler.clear();
489 removalHandler.clear();
490 uncheckedHandler.clear();
491 sunApiHandler.clear();
492 }
493
494 public void putCompiled(ClassSymbol csym) {
495 compiled.put(Pair.of(csym.packge().modle, csym.flatname), csym);
496 }
497
498 public ClassSymbol getCompiled(ClassSymbol csym) {
499 return compiled.get(Pair.of(csym.packge().modle, csym.flatname));
500 }
501
502 public ClassSymbol getCompiled(ModuleSymbol msym, Name flatname) {
503 return compiled.get(Pair.of(msym, flatname));
504 }
505
506 public void removeCompiled(ClassSymbol csym) {
507 compiled.remove(Pair.of(csym.packge().modle, csym.flatname));
508 }
509
510 /* *************************************************************************
511 * Type Checking
512 **************************************************************************/
513
514 /**
515 * A check context is an object that can be used to perform compatibility
516 * checks - depending on the check context, meaning of 'compatibility' might
517 * vary significantly.
518 */
519 public interface CheckContext {
520 /**
521 * Is type 'found' compatible with type 'req' in given context
522 */
523 boolean compatible(Type found, Type req, Warner warn);
524 /**
525 * Report a check error
526 */
527 void report(DiagnosticPosition pos, JCDiagnostic details);
528 /**
529 * Obtain a warner for this check context
530 */
531 public Warner checkWarner(DiagnosticPosition pos, Type found, Type req);
532
533 public InferenceContext inferenceContext();
534
535 public DeferredAttr.DeferredAttrContext deferredAttrContext();
536 }
537
538 /**
539 * This class represent a check context that is nested within another check
540 * context - useful to check sub-expressions. The default behavior simply
541 * redirects all method calls to the enclosing check context leveraging
542 * the forwarding pattern.
543 */
544 static class NestedCheckContext implements CheckContext {
545 CheckContext enclosingContext;
546
547 NestedCheckContext(CheckContext enclosingContext) {
548 this.enclosingContext = enclosingContext;
549 }
550
551 public boolean compatible(Type found, Type req, Warner warn) {
552 return enclosingContext.compatible(found, req, warn);
553 }
554
555 public void report(DiagnosticPosition pos, JCDiagnostic details) {
556 enclosingContext.report(pos, details);
557 }
558
559 public Warner checkWarner(DiagnosticPosition pos, Type found, Type req) {
560 return enclosingContext.checkWarner(pos, found, req);
561 }
562
563 public InferenceContext inferenceContext() {
564 return enclosingContext.inferenceContext();
565 }
566
567 public DeferredAttrContext deferredAttrContext() {
568 return enclosingContext.deferredAttrContext();
569 }
570 }
571
572 /**
573 * Check context to be used when evaluating assignment/return statements
574 */
575 CheckContext basicHandler = new CheckContext() {
576 public void report(DiagnosticPosition pos, JCDiagnostic details) {
577 log.error(pos, Errors.ProbFoundReq(details));
578 }
579 public boolean compatible(Type found, Type req, Warner warn) {
580 return types.isAssignable(found, req, warn);
581 }
582
583 public Warner checkWarner(DiagnosticPosition pos, Type found, Type req) {
584 return convertWarner(pos, found, req);
585 }
586
587 public InferenceContext inferenceContext() {
588 return infer.emptyContext;
589 }
590
591 public DeferredAttrContext deferredAttrContext() {
592 return deferredAttr.emptyDeferredAttrContext;
593 }
594
595 @Override
596 public String toString() {
597 return "CheckContext: basicHandler";
598 }
599 };
600
601 /** Check that a given type is assignable to a given proto-type.
602 * If it is, return the type, otherwise return errType.
603 * @param pos Position to be used for error reporting.
604 * @param found The type that was found.
605 * @param req The type that was required.
606 */
607 public Type checkType(DiagnosticPosition pos, Type found, Type req) {
608 return checkType(pos, found, req, basicHandler);
609 }
610
611 Type checkType(final DiagnosticPosition pos, final Type found, final Type req, final CheckContext checkContext) {
612 final InferenceContext inferenceContext = checkContext.inferenceContext();
613 if (inferenceContext.free(req) || inferenceContext.free(found)) {
614 inferenceContext.addFreeTypeListener(List.of(req, found),
615 solvedContext -> checkType(pos, solvedContext.asInstType(found), solvedContext.asInstType(req), checkContext));
616 } else {
617 if (found.hasTag(CLASS)) {
618 if (inferenceContext != infer.emptyContext)
619 checkParameterizationByPrimitiveClass(pos, found);
620 }
621 }
622 if (req.hasTag(ERROR))
623 return req;
624 if (req.hasTag(NONE))
625 return found;
626 if (checkContext.compatible(found, req, checkContext.checkWarner(pos, found, req))) {
627 return found;
628 } else {
629 if (found.isNumeric() && req.isNumeric()) {
630 checkContext.report(pos, diags.fragment(Fragments.PossibleLossOfPrecision(found, req)));
631 return types.createErrorType(found);
632 }
633 checkContext.report(pos, diags.fragment(Fragments.InconvertibleTypes(found, req)));
634 return types.createErrorType(found);
635 }
636 }
637
638 /** Check that a given type can be cast to a given target type.
639 * Return the result of the cast.
640 * @param pos Position to be used for error reporting.
641 * @param found The type that is being cast.
642 * @param req The target type of the cast.
643 */
644 Type checkCastable(DiagnosticPosition pos, Type found, Type req) {
645 return checkCastable(pos, found, req, basicHandler);
646 }
647 Type checkCastable(DiagnosticPosition pos, Type found, Type req, CheckContext checkContext) {
648 if (types.isCastable(found, req, castWarner(pos, found, req))) {
649 return req;
650 } else {
651 checkContext.report(pos, diags.fragment(Fragments.InconvertibleTypes(found, req)));
652 return types.createErrorType(found);
653 }
654 }
655
656 /** Check for redundant casts (i.e. where source type is a subtype of target type)
657 * The problem should only be reported for non-292 cast
658 */
659 public void checkRedundantCast(Env<AttrContext> env, final JCTypeCast tree) {
660 if (!tree.type.isErroneous()
661 && types.isSameType(tree.expr.type, tree.clazz.type)
662 && !(ignoreAnnotatedCasts && TreeInfo.containsTypeAnnotation(tree.clazz))
663 && !is292targetTypeCast(tree)) {
664 deferredLintHandler.report(() -> {
665 if (lint.isEnabled(LintCategory.CAST))
666 log.warning(LintCategory.CAST,
667 tree.pos(), Warnings.RedundantCast(tree.clazz.type));
668 });
669 }
670 }
671 //where
672 private boolean is292targetTypeCast(JCTypeCast tree) {
673 boolean is292targetTypeCast = false;
674 JCExpression expr = TreeInfo.skipParens(tree.expr);
675 if (expr.hasTag(APPLY)) {
676 JCMethodInvocation apply = (JCMethodInvocation)expr;
677 Symbol sym = TreeInfo.symbol(apply.meth);
678 is292targetTypeCast = sym != null &&
679 sym.kind == MTH &&
680 (sym.flags() & HYPOTHETICAL) != 0;
681 }
682 return is292targetTypeCast;
683 }
684
685 private static final boolean ignoreAnnotatedCasts = true;
686
687 /** Check that a type is within some bounds.
688 *
689 * Used in TypeApply to verify that, e.g., X in {@code V<X>} is a valid
690 * type argument.
691 * @param a The type that should be bounded by bs.
692 * @param bound The bound.
693 */
694 private boolean checkExtends(Type a, Type bound) {
695 if (a.isUnbound()) {
696 return true;
697 } else if (!a.hasTag(WILDCARD)) {
698 a = types.cvarUpperBound(a);
699 return types.isSubtype(a, bound);
700 } else if (a.isExtendsBound()) {
701 return types.isCastable(bound, types.wildUpperBound(a), types.noWarnings);
702 } else if (a.isSuperBound()) {
703 return !types.notSoftSubtype(types.wildLowerBound(a), bound);
704 }
705 return true;
706 }
707
708 /** Check that type is different from 'void'.
709 * @param pos Position to be used for error reporting.
710 * @param t The type to be checked.
711 */
712 Type checkNonVoid(DiagnosticPosition pos, Type t) {
713 if (t.hasTag(VOID)) {
714 log.error(pos, Errors.VoidNotAllowedHere);
715 return types.createErrorType(t);
716 } else {
717 return t;
718 }
719 }
720
721 Type checkClassOrArrayType(DiagnosticPosition pos, Type t) {
722 if (!t.hasTag(CLASS) && !t.hasTag(ARRAY) && !t.hasTag(ERROR)) {
723 return typeTagError(pos,
724 diags.fragment(Fragments.TypeReqClassArray),
725 asTypeParam(t));
726 } else {
727 return t;
728 }
729 }
730
731 /** Check that type is a class or interface type.
732 * @param pos Position to be used for error reporting.
733 * @param t The type to be checked.
734 */
735 Type checkClassType(DiagnosticPosition pos, Type t) {
736 if (!t.hasTag(CLASS) && !t.hasTag(ERROR)) {
737 return typeTagError(pos,
738 diags.fragment(Fragments.TypeReqClass),
739 asTypeParam(t));
740 } else {
741 return t;
742 }
743 }
744 //where
745 private Object asTypeParam(Type t) {
746 return (t.hasTag(TYPEVAR))
747 ? diags.fragment(Fragments.TypeParameter(t))
748 : t;
749 }
750
751 void checkConstraintsOfValueClass(DiagnosticPosition pos, ClassSymbol c) {
752 for (Type st : types.closure(c.type)) {
753 if (st == null || st.tsym == null || st.tsym.kind == ERR)
754 continue;
755 if (st.tsym == syms.objectType.tsym || st.tsym == syms.recordType.tsym || st.isInterface())
756 continue;
757 if (!st.tsym.isAbstract()) {
758 if (c != st.tsym) {
759 log.error(pos, Errors.ConcreteSupertypeForValueClass(c, st));
760 }
761 continue;
762 }
763 // dealing with an abstract value or value super class below.
764 Fragment fragment = c.isAbstract() && c.isValueClass() && c == st.tsym ? Fragments.AbstractValueClass(c) : Fragments.SuperclassOfValueClass(c, st);
765 if ((st.tsym.flags() & HASINITBLOCK) != 0) {
766 log.error(pos, Errors.SuperClassDeclaresInitBlock(fragment));
767 }
768 // No instance fields and no arged constructors both mean inner classes
769 // cannot be super classes for primitive classes.
770 Type encl = st.getEnclosingType();
771 if (encl != null && encl.hasTag(CLASS)) {
772 log.error(pos, Errors.SuperClassCannotBeInner(fragment));
773 }
774 for (Symbol s : st.tsym.members().getSymbols(NON_RECURSIVE)) {
775 switch (s.kind) {
776 case VAR:
777 if ((s.flags() & STATIC) == 0) {
778 log.error(pos, Errors.SuperFieldNotAllowed(s, fragment));
779 }
780 break;
781 case MTH:
782 if ((s.flags() & (SYNCHRONIZED | STATIC)) == SYNCHRONIZED) {
783 log.error(pos, Errors.SuperMethodCannotBeSynchronized(s, c, st));
784 } else if (s.isConstructor()) {
785 MethodSymbol m = (MethodSymbol)s;
786 if (m.getParameters().size() > 0) {
787 log.error(pos, Errors.SuperConstructorCannotTakeArguments(m, fragment));
788 } else if (m.getTypeParameters().size() > 0) {
789 log.error(pos, Errors.SuperConstructorCannotBeGeneric(m, fragment));
790 } else if (m.type.getThrownTypes().size() > 0) {
791 log.error(pos, Errors.SuperConstructorCannotThrow(m, fragment));
792 } else if (protection(m.flags()) > protection(m.owner.flags())) {
793 log.error(pos, Errors.SuperConstructorAccessRestricted(m, fragment));
794 } else if ((m.flags() & EMPTYNOARGCONSTR) == 0) {
795 log.error(pos, Errors.SuperNoArgConstructorMustBeEmpty(m, fragment));
796 }
797 }
798 break;
799 }
800 }
801 }
802 }
803
804 /** Check that type is a valid qualifier for a constructor reference expression
805 */
806 Type checkConstructorRefType(JCExpression expr, Type t) {
807 t = checkClassOrArrayType(expr, t);
808 if (t.hasTag(CLASS)) {
809 if ((t.tsym.flags() & (ABSTRACT | INTERFACE)) != 0) {
810 log.error(expr, Errors.AbstractCantBeInstantiated(t.tsym));
811 t = types.createErrorType(t);
812 } else if ((t.tsym.flags() & ENUM) != 0) {
813 log.error(expr, Errors.EnumCantBeInstantiated);
814 t = types.createErrorType(t);
815 } else {
816 // Projection types may not be mentioned in constructor references
817 if (expr.hasTag(SELECT)) {
818 JCFieldAccess fieldAccess = (JCFieldAccess) expr;
819 if (fieldAccess.selected.type.isPrimitiveClass() &&
820 (fieldAccess.name == names.ref || fieldAccess.name == names.val)) {
821 log.error(expr, Errors.ProjectionCantBeInstantiated);
822 t = types.createErrorType(t);
823 }
824 }
825 t = checkClassType(expr, t, true);
826 }
827 } else if (t.hasTag(ARRAY)) {
828 if (!types.isReifiable(((ArrayType)t).elemtype)) {
829 log.error(expr, Errors.GenericArrayCreation);
830 t = types.createErrorType(t);
831 }
832 }
833 return t;
834 }
835
836 /** Check that type is a class or interface type.
837 * @param pos Position to be used for error reporting.
838 * @param t The type to be checked.
839 * @param noBounds True if type bounds are illegal here.
840 */
841 Type checkClassType(DiagnosticPosition pos, Type t, boolean noBounds) {
842 t = checkClassType(pos, t);
843 if (noBounds && t.isParameterized()) {
844 List<Type> args = t.getTypeArguments();
845 while (args.nonEmpty()) {
846 if (args.head.hasTag(WILDCARD))
847 return typeTagError(pos,
848 diags.fragment(Fragments.TypeReqExact),
849 args.head);
850 args = args.tail;
851 }
852 }
853 return t;
854 }
855
856 /** Check that type is a reference type, i.e. a class, interface or array type
857 * or a type variable.
858 * @param pos Position to be used for error reporting.
859 * @param t The type to be checked.
860 * @param primitiveClassOK If false, a primitive class does not qualify
861 */
862 Type checkRefType(DiagnosticPosition pos, Type t, boolean primitiveClassOK) {
863 if (t.isReference() && (primitiveClassOK || !t.isPrimitiveClass()))
864 return t;
865 else
866 return typeTagError(pos,
867 diags.fragment(Fragments.TypeReqRef),
868 t);
869 }
870
871 /** Check that type is an identity type, i.e. not a primitive/value type
872 * nor its reference projection. When not discernible statically,
873 * give it the benefit of doubt and defer to runtime.
874 *
875 * @param pos Position to be used for error reporting.
876 * @param t The type to be checked.
877 */
878 Type checkIdentityType(DiagnosticPosition pos, Type t) {
879
880 if (t.isPrimitive() || t.isValueClass() || t.isValueInterface() || t.isReferenceProjection())
881 return typeTagError(pos,
882 diags.fragment(Fragments.TypeReqIdentity),
883 t);
884
885 return t;
886 }
887
888 /** Check that type is a reference type, i.e. a class, interface or array type
889 * or a type variable.
890 * @param pos Position to be used for error reporting.
891 * @param t The type to be checked.
892 */
893 Type checkRefType(DiagnosticPosition pos, Type t) {
894 return checkRefType(pos, t, true);
895 }
896
897 /** Check that each type is a reference type, i.e. a class, interface or array type
898 * or a type variable.
899 * @param trees Original trees, used for error reporting.
900 * @param types The types to be checked.
901 */
902 List<Type> checkRefTypes(List<JCExpression> trees, List<Type> types) {
903 List<JCExpression> tl = trees;
904 for (List<Type> l = types; l.nonEmpty(); l = l.tail) {
905 l.head = checkRefType(tl.head.pos(), l.head, false);
906 tl = tl.tail;
907 }
908 return types;
909 }
910
911 /** Check that type is a null or reference type.
912 * @param pos Position to be used for error reporting.
913 * @param t The type to be checked.
914 */
915 Type checkNullOrRefType(DiagnosticPosition pos, Type t) {
916 if (t.isReference() || t.hasTag(BOT))
917 return t;
918 else
919 return typeTagError(pos,
920 diags.fragment(Fragments.TypeReqRef),
921 t);
922 }
923
924 /** Check that flag set does not contain elements of two conflicting sets. s
925 * Return true if it doesn't.
926 * @param pos Position to be used for error reporting.
927 * @param flags The set of flags to be checked.
928 * @param set1 Conflicting flags set #1.
929 * @param set2 Conflicting flags set #2.
930 */
931 boolean checkDisjoint(DiagnosticPosition pos, long flags, long set1, long set2) {
932 if ((flags & set1) != 0 && (flags & set2) != 0) {
933 log.error(pos,
934 Errors.IllegalCombinationOfModifiers(asFlagSet(TreeInfo.firstFlag(flags & set1)),
935 asFlagSet(TreeInfo.firstFlag(flags & set2))));
936 return false;
937 } else
938 return true;
939 }
940
941 void checkParameterizationByPrimitiveClass(DiagnosticPosition pos, Type t) {
942 parameterizationByPrimitiveClassChecker.visit(t, pos);
943 }
944
945 /** parameterizationByPrimitiveClassChecker: A type visitor that descends down the given type looking for instances of primitive classes
946 * being used as type arguments and issues error against those usages.
947 */
948 private final Types.SimpleVisitor<Void, DiagnosticPosition> parameterizationByPrimitiveClassChecker =
949 new Types.SimpleVisitor<Void, DiagnosticPosition>() {
950
951 @Override
952 public Void visitType(Type t, DiagnosticPosition pos) {
953 return null;
954 }
955
956 @Override
957 public Void visitClassType(ClassType t, DiagnosticPosition pos) {
958 for (Type targ : t.allparams()) {
959 if (targ.isPrimitiveClass()) {
960 log.error(pos, Errors.GenericParameterizationWithPrimitiveClass(t));
961 }
962 visit(targ, pos);
963 }
964 return null;
965 }
966
967 @Override
968 public Void visitTypeVar(TypeVar t, DiagnosticPosition pos) {
969 return null;
970 }
971
972 @Override
973 public Void visitCapturedType(CapturedType t, DiagnosticPosition pos) {
974 return null;
975 }
976
977 @Override
978 public Void visitArrayType(ArrayType t, DiagnosticPosition pos) {
979 return visit(t.elemtype, pos);
980 }
981
982 @Override
983 public Void visitWildcardType(WildcardType t, DiagnosticPosition pos) {
984 return visit(t.type, pos);
985 }
986 };
987
988
989
990 /** Check that usage of diamond operator is correct (i.e. diamond should not
991 * be used with non-generic classes or in anonymous class creation expressions)
992 */
993 Type checkDiamond(JCNewClass tree, Type t) {
994 if (!TreeInfo.isDiamond(tree) ||
995 t.isErroneous()) {
996 return checkClassType(tree.clazz.pos(), t, true);
997 } else {
998 if (tree.def != null && !Feature.DIAMOND_WITH_ANONYMOUS_CLASS_CREATION.allowedInSource(source)) {
999 log.error(DiagnosticFlag.SOURCE_LEVEL, tree.clazz.pos(),
1000 Errors.CantApplyDiamond1(t, Feature.DIAMOND_WITH_ANONYMOUS_CLASS_CREATION.fragment(source.name)));
1001 }
1002 if (t.tsym.type.getTypeArguments().isEmpty()) {
1003 log.error(tree.clazz.pos(),
1004 Errors.CantApplyDiamond1(t,
1005 Fragments.DiamondNonGeneric(t)));
1006 return types.createErrorType(t);
1007 } else if (tree.typeargs != null &&
1008 tree.typeargs.nonEmpty()) {
1009 log.error(tree.clazz.pos(),
1010 Errors.CantApplyDiamond1(t,
1011 Fragments.DiamondAndExplicitParams(t)));
1012 return types.createErrorType(t);
1013 } else {
1014 return t;
1015 }
1016 }
1017 }
1018
1019 /** Check that the type inferred using the diamond operator does not contain
1020 * non-denotable types such as captured types or intersection types.
1021 * @param t the type inferred using the diamond operator
1022 * @return the (possibly empty) list of non-denotable types.
1023 */
1024 List<Type> checkDiamondDenotable(ClassType t) {
1025 ListBuffer<Type> buf = new ListBuffer<>();
1026 for (Type arg : t.allparams()) {
1027 if (!checkDenotable(arg)) {
1028 buf.append(arg);
1029 }
1030 }
1031 return buf.toList();
1032 }
1033
1034 public boolean checkDenotable(Type t) {
1035 return denotableChecker.visit(t, null);
1036 }
1037 // where
1038
1039 /** diamondTypeChecker: A type visitor that descends down the given type looking for non-denotable
1040 * types. The visit methods return false as soon as a non-denotable type is encountered and true
1041 * otherwise.
1042 */
1043 private static final Types.SimpleVisitor<Boolean, Void> denotableChecker = new Types.SimpleVisitor<Boolean, Void>() {
1044 @Override
1045 public Boolean visitType(Type t, Void s) {
1046 return true;
1047 }
1048 @Override
1049 public Boolean visitClassType(ClassType t, Void s) {
1050 if (t.isUnion() || t.isIntersection()) {
1051 return false;
1052 }
1053 for (Type targ : t.allparams()) {
1054 if (!visit(targ, s)) {
1055 return false;
1056 }
1057 }
1058 return true;
1059 }
1060
1061 @Override
1062 public Boolean visitTypeVar(TypeVar t, Void s) {
1063 /* Any type variable mentioned in the inferred type must have been declared as a type parameter
1064 (i.e cannot have been produced by inference (18.4))
1065 */
1066 return (t.tsym.flags() & SYNTHETIC) == 0;
1067 }
1068
1069 @Override
1070 public Boolean visitCapturedType(CapturedType t, Void s) {
1071 /* Any type variable mentioned in the inferred type must have been declared as a type parameter
1072 (i.e cannot have been produced by capture conversion (5.1.10))
1073 */
1074 return false;
1075 }
1076
1077 @Override
1078 public Boolean visitArrayType(ArrayType t, Void s) {
1079 return visit(t.elemtype, s);
1080 }
1081
1082 @Override
1083 public Boolean visitWildcardType(WildcardType t, Void s) {
1084 return visit(t.type, s);
1085 }
1086 };
1087
1088 void checkVarargsMethodDecl(Env<AttrContext> env, JCMethodDecl tree) {
1089 MethodSymbol m = tree.sym;
1090 boolean hasTrustMeAnno = m.attribute(syms.trustMeType.tsym) != null;
1091 Type varargElemType = null;
1092 if (m.isVarArgs()) {
1093 varargElemType = types.elemtype(tree.params.last().type);
1094 }
1095 if (hasTrustMeAnno && !isTrustMeAllowedOnMethod(m)) {
1096 if (varargElemType != null) {
1097 JCDiagnostic msg = Feature.PRIVATE_SAFE_VARARGS.allowedInSource(source) ?
1098 diags.fragment(Fragments.VarargsTrustmeOnVirtualVarargs(m)) :
1099 diags.fragment(Fragments.VarargsTrustmeOnVirtualVarargsFinalOnly(m));
1100 log.error(tree,
1101 Errors.VarargsInvalidTrustmeAnno(syms.trustMeType.tsym,
1102 msg));
1103 } else {
1104 log.error(tree,
1105 Errors.VarargsInvalidTrustmeAnno(syms.trustMeType.tsym,
1106 Fragments.VarargsTrustmeOnNonVarargsMeth(m)));
1107 }
1108 } else if (hasTrustMeAnno && varargElemType != null &&
1109 types.isReifiable(varargElemType)) {
1110 warnUnsafeVararg(tree, Warnings.VarargsRedundantTrustmeAnno(
1111 syms.trustMeType.tsym,
1112 diags.fragment(Fragments.VarargsTrustmeOnReifiableVarargs(varargElemType))));
1113 }
1114 else if (!hasTrustMeAnno && varargElemType != null &&
1115 !types.isReifiable(varargElemType)) {
1116 warnUnchecked(tree.params.head.pos(), Warnings.UncheckedVarargsNonReifiableType(varargElemType));
1117 }
1118 }
1119 //where
1120 private boolean isTrustMeAllowedOnMethod(Symbol s) {
1121 return (s.flags() & VARARGS) != 0 &&
1122 (s.isConstructor() ||
1123 (s.flags() & (STATIC | FINAL |
1124 (Feature.PRIVATE_SAFE_VARARGS.allowedInSource(source) ? PRIVATE : 0) )) != 0);
1125 }
1126
1127 Type checkLocalVarType(DiagnosticPosition pos, Type t, Name name) {
1128 //check that resulting type is not the null type
1129 if (t.hasTag(BOT)) {
1130 log.error(pos, Errors.CantInferLocalVarType(name, Fragments.LocalCantInferNull));
1131 return types.createErrorType(t);
1132 } else if (t.hasTag(VOID)) {
1133 log.error(pos, Errors.CantInferLocalVarType(name, Fragments.LocalCantInferVoid));
1134 return types.createErrorType(t);
1135 }
1136
1137 //upward project the initializer type
1138 Type varType = types.upward(t, types.captures(t));
1139 if (varType.hasTag(CLASS)) {
1140 checkParameterizationByPrimitiveClass(pos, varType);
1141 }
1142 return varType;
1143 }
1144
1145 public void checkForSuspectClassLiteralComparison(
1146 final JCBinary tree,
1147 final Type leftType,
1148 final Type rightType) {
1149
1150 if (lint.isEnabled(LintCategory.MIGRATION)) {
1151 if (isInvocationOfGetClass(tree.lhs) && isClassOfSomeInterface(rightType) ||
1152 isInvocationOfGetClass(tree.rhs) && isClassOfSomeInterface(leftType)) {
1153 log.warning(LintCategory.MIGRATION, tree.pos(), Warnings.GetClassComparedWithInterface);
1154 }
1155 }
1156 }
1157 //where
1158 private boolean isClassOfSomeInterface(Type someClass) {
1159 if (someClass.tsym.flatName() == names.java_lang_Class) {
1160 List<Type> arguments = someClass.getTypeArguments();
1161 if (arguments.length() == 1) {
1162 return arguments.head.isInterface();
1163 }
1164 }
1165 return false;
1166 }
1167 //where
1168 private boolean isInvocationOfGetClass(JCExpression tree) {
1169 tree = TreeInfo.skipParens(tree);
1170 if (tree.hasTag(APPLY)) {
1171 JCMethodInvocation apply = (JCMethodInvocation)tree;
1172 MethodSymbol msym = (MethodSymbol)TreeInfo.symbol(apply.meth);
1173 return msym.name == names.getClass && msym.implementedIn(syms.objectType.tsym, types) != null;
1174 }
1175 return false;
1176 }
1177
1178 Type checkMethod(final Type mtype,
1179 final Symbol sym,
1180 final Env<AttrContext> env,
1181 final List<JCExpression> argtrees,
1182 final List<Type> argtypes,
1183 final boolean useVarargs,
1184 InferenceContext inferenceContext) {
1185 // System.out.println("call : " + env.tree);
1186 // System.out.println("method : " + owntype);
1187 // System.out.println("actuals: " + argtypes);
1188 if (inferenceContext.free(mtype)) {
1189 inferenceContext.addFreeTypeListener(List.of(mtype),
1190 solvedContext -> checkMethod(solvedContext.asInstType(mtype), sym, env, argtrees, argtypes, useVarargs, solvedContext));
1191 return mtype;
1192 }
1193 Type owntype = mtype;
1194 List<Type> formals = owntype.getParameterTypes();
1195 List<Type> nonInferred = sym.type.getParameterTypes();
1196 if (nonInferred.length() != formals.length()) nonInferred = formals;
1197 Type last = useVarargs ? formals.last() : null;
1198 if (sym.name == names.init && sym.owner == syms.enumSym) {
1199 formals = formals.tail.tail;
1200 nonInferred = nonInferred.tail.tail;
1201 }
1202 if ((sym.flags() & ANONCONSTR_BASED) != 0) {
1203 formals = formals.tail;
1204 nonInferred = nonInferred.tail;
1205 }
1206 List<JCExpression> args = argtrees;
1207 if (args != null) {
1208 //this is null when type-checking a method reference
1209 while (formals.head != last) {
1210 JCTree arg = args.head;
1211 Warner warn = convertWarner(arg.pos(), arg.type, nonInferred.head);
1212 assertConvertible(arg, arg.type, formals.head, warn);
1213 args = args.tail;
1214 formals = formals.tail;
1215 nonInferred = nonInferred.tail;
1216 }
1217 if (useVarargs) {
1218 Type varArg = types.elemtype(last);
1219 while (args.tail != null) {
1220 JCTree arg = args.head;
1221 Warner warn = convertWarner(arg.pos(), arg.type, varArg);
1222 assertConvertible(arg, arg.type, varArg, warn);
1223 args = args.tail;
1224 }
1225 } else if ((sym.flags() & (VARARGS | SIGNATURE_POLYMORPHIC)) == VARARGS) {
1226 // non-varargs call to varargs method
1227 Type varParam = owntype.getParameterTypes().last();
1228 Type lastArg = argtypes.last();
1229 if (types.isSubtypeUnchecked(lastArg, types.elemtype(varParam)) &&
1230 !types.isSameType(types.erasure(varParam), types.erasure(lastArg)))
1231 log.warning(argtrees.last().pos(),
1232 Warnings.InexactNonVarargsCall(types.elemtype(varParam),varParam));
1233 }
1234 }
1235 if (useVarargs) {
1236 Type argtype = owntype.getParameterTypes().last();
1237 if (!types.isReifiable(argtype) &&
1238 (sym.baseSymbol().attribute(syms.trustMeType.tsym) == null ||
1239 !isTrustMeAllowedOnMethod(sym))) {
1240 warnUnchecked(env.tree.pos(), Warnings.UncheckedGenericArrayCreation(argtype));
1241 }
1242 TreeInfo.setVarargsElement(env.tree, types.elemtype(argtype));
1243 }
1244 return owntype;
1245 }
1246 //where
1247 private void assertConvertible(JCTree tree, Type actual, Type formal, Warner warn) {
1248 if (types.isConvertible(actual, formal, warn))
1249 return;
1250
1251 if (formal.isCompound()
1252 && types.isSubtype(actual, types.supertype(formal))
1253 && types.isSubtypeUnchecked(actual, types.interfaces(formal), warn))
1254 return;
1255 }
1256
1257 /**
1258 * Check that type 't' is a valid instantiation of a generic class
1259 * (see JLS 4.5)
1260 *
1261 * @param t class type to be checked
1262 * @return true if 't' is well-formed
1263 */
1264 public boolean checkValidGenericType(Type t) {
1265 return firstIncompatibleTypeArg(t) == null;
1266 }
1267 //WHERE
1268 private Type firstIncompatibleTypeArg(Type type) {
1269 List<Type> formals = type.tsym.type.allparams();
1270 List<Type> actuals = type.allparams();
1271 List<Type> args = type.getTypeArguments();
1272 List<Type> forms = type.tsym.type.getTypeArguments();
1273 ListBuffer<Type> bounds_buf = new ListBuffer<>();
1274
1275 // For matching pairs of actual argument types `a' and
1276 // formal type parameters with declared bound `b' ...
1277 while (args.nonEmpty() && forms.nonEmpty()) {
1278 // exact type arguments needs to know their
1279 // bounds (for upper and lower bound
1280 // calculations). So we create new bounds where
1281 // type-parameters are replaced with actuals argument types.
1282 bounds_buf.append(types.subst(forms.head.getUpperBound(), formals, actuals));
1283 args = args.tail;
1284 forms = forms.tail;
1285 }
1286
1287 args = type.getTypeArguments();
1288 List<Type> tvars_cap = types.substBounds(formals,
1289 formals,
1290 types.capture(type).allparams());
1291 while (args.nonEmpty() && tvars_cap.nonEmpty()) {
1292 // Let the actual arguments know their bound
1293 args.head.withTypeVar((TypeVar)tvars_cap.head);
1294 args = args.tail;
1295 tvars_cap = tvars_cap.tail;
1296 }
1297
1298 args = type.getTypeArguments();
1299 List<Type> bounds = bounds_buf.toList();
1300
1301 while (args.nonEmpty() && bounds.nonEmpty()) {
1302 Type actual = args.head;
1303 if (!isTypeArgErroneous(actual) &&
1304 !bounds.head.isErroneous() &&
1305 !checkExtends(actual, bounds.head)) {
1306 return args.head;
1307 }
1308 args = args.tail;
1309 bounds = bounds.tail;
1310 }
1311
1312 args = type.getTypeArguments();
1313 bounds = bounds_buf.toList();
1314
1315 for (Type arg : types.capture(type).getTypeArguments()) {
1316 if (arg.hasTag(TYPEVAR) &&
1317 arg.getUpperBound().isErroneous() &&
1318 !bounds.head.isErroneous() &&
1319 !isTypeArgErroneous(args.head)) {
1320 return args.head;
1321 }
1322 bounds = bounds.tail;
1323 args = args.tail;
1324 }
1325
1326 return null;
1327 }
1328 //where
1329 boolean isTypeArgErroneous(Type t) {
1330 return isTypeArgErroneous.visit(t);
1331 }
1332
1333 Types.UnaryVisitor<Boolean> isTypeArgErroneous = new Types.UnaryVisitor<Boolean>() {
1334 public Boolean visitType(Type t, Void s) {
1335 return t.isErroneous();
1336 }
1337 @Override
1338 public Boolean visitTypeVar(TypeVar t, Void s) {
1339 return visit(t.getUpperBound());
1340 }
1341 @Override
1342 public Boolean visitCapturedType(CapturedType t, Void s) {
1343 return visit(t.getUpperBound()) ||
1344 visit(t.getLowerBound());
1345 }
1346 @Override
1347 public Boolean visitWildcardType(WildcardType t, Void s) {
1348 return visit(t.type);
1349 }
1350 };
1351
1352 /** Check that given modifiers are legal for given symbol and
1353 * return modifiers together with any implicit modifiers for that symbol.
1354 * Warning: we can't use flags() here since this method
1355 * is called during class enter, when flags() would cause a premature
1356 * completion.
1357 * @param pos Position to be used for error reporting.
1358 * @param flags The set of modifiers given in a definition.
1359 * @param sym The defined symbol.
1360 */
1361 long checkFlags(DiagnosticPosition pos, long flags, Symbol sym, JCTree tree) {
1362 long mask;
1363 long implicit = 0;
1364
1365 switch (sym.kind) {
1366 case VAR:
1367 if (TreeInfo.isReceiverParam(tree))
1368 mask = ReceiverParamFlags;
1369 else if (sym.owner.kind != TYP)
1370 mask = LocalVarFlags;
1371 else if ((sym.owner.flags_field & INTERFACE) != 0)
1372 mask = implicit = InterfaceVarFlags;
1373 else {
1374 mask = VarFlags;
1375 if (sym.owner.type.isValueClass() && (flags & STATIC) == 0) {
1376 implicit |= FINAL;
1377 }
1378 }
1379 break;
1380 case MTH:
1381 if (sym.name == names.init) {
1382 if ((sym.owner.flags_field & ENUM) != 0) {
1383 // enum constructors cannot be declared public or
1384 // protected and must be implicitly or explicitly
1385 // private
1386 implicit = PRIVATE;
1387 mask = PRIVATE;
1388 } else
1389 mask = ConstructorFlags;
1390 } else if ((sym.owner.flags_field & INTERFACE) != 0) {
1391 if ((sym.owner.flags_field & ANNOTATION) != 0) {
1392 mask = AnnotationTypeElementMask;
1393 implicit = PUBLIC | ABSTRACT;
1394 } else if ((flags & (DEFAULT | STATIC | PRIVATE)) != 0) {
1395 mask = InterfaceMethodMask;
1396 implicit = (flags & PRIVATE) != 0 ? 0 : PUBLIC;
1397 if ((flags & DEFAULT) != 0) {
1398 implicit |= ABSTRACT;
1399 }
1400 } else {
1401 mask = implicit = InterfaceMethodFlags;
1402 }
1403 } else if ((sym.owner.flags_field & RECORD) != 0) {
1404 mask = ((sym.owner.flags_field & VALUE_CLASS) != 0 && (flags & Flags.STATIC) == 0) ?
1405 RecordMethodFlags & ~SYNCHRONIZED : RecordMethodFlags;
1406 } else {
1407 // value objects do not have an associated monitor/lock
1408 mask = ((sym.owner.flags_field & VALUE_CLASS) != 0 && (flags & Flags.STATIC) == 0) ?
1409 MethodFlags & ~SYNCHRONIZED : MethodFlags;
1410 }
1411 if ((flags & STRICTFP) != 0) {
1412 warnOnExplicitStrictfp(pos);
1413 }
1414 // Imply STRICTFP if owner has STRICTFP set.
1415 if (((flags|implicit) & Flags.ABSTRACT) == 0 ||
1416 ((flags) & Flags.DEFAULT) != 0)
1417 implicit |= sym.owner.flags_field & STRICTFP;
1418 break;
1419 case TYP:
1420 if (sym.owner.kind.matches(KindSelector.VAL_MTH) ||
1421 (sym.isDirectlyOrIndirectlyLocal() && (flags & ANNOTATION) != 0)) {
1422 boolean implicitlyStatic = !sym.isAnonymous() &&
1423 ((flags & RECORD) != 0 || (flags & ENUM) != 0 || (flags & INTERFACE) != 0);
1424 boolean staticOrImplicitlyStatic = (flags & STATIC) != 0 || implicitlyStatic;
1425 // local statics are allowed only if records are allowed too
1426 mask = staticOrImplicitlyStatic && allowRecords && (flags & ANNOTATION) == 0 ? ExtendedStaticLocalClassFlags : ExtendedLocalClassFlags;
1427 implicit = implicitlyStatic ? STATIC : implicit;
1428 } else if (sym.owner.kind == TYP) {
1429 // statics in inner classes are allowed only if records are allowed too
1430 mask = ((flags & STATIC) != 0) && allowRecords && (flags & ANNOTATION) == 0 ? ExtendedMemberStaticClassFlags : ExtendedMemberClassFlags;
1431 if (sym.owner.owner.kind == PCK ||
1432 (sym.owner.flags_field & STATIC) != 0) {
1433 mask |= STATIC;
1434 } else if (!allowRecords && ((flags & ENUM) != 0 || (flags & RECORD) != 0)) {
1435 log.error(pos, Errors.StaticDeclarationNotAllowedInInnerClasses);
1436 }
1437 // Nested interfaces and enums are always STATIC (Spec ???)
1438 if ((flags & (INTERFACE | ENUM | RECORD)) != 0 ) implicit = STATIC;
1439 } else {
1440 mask = ExtendedClassFlags;
1441 }
1442 // Interfaces are always ABSTRACT
1443 if ((flags & INTERFACE) != 0) implicit |= ABSTRACT;
1444
1445 if ((flags & ENUM) != 0) {
1446 // enums can't be declared abstract, final, sealed or non-sealed or primitive/value
1447 mask &= ~(ABSTRACT | FINAL | SEALED | NON_SEALED | PRIMITIVE_CLASS | VALUE_CLASS);
1448 implicit |= implicitEnumFinalFlag(tree);
1449 }
1450 if ((flags & RECORD) != 0) {
1451 // records can't be declared abstract
1452 mask &= ~ABSTRACT;
1453 implicit |= FINAL;
1454 }
1455 if ((flags & STRICTFP) != 0) {
1456 warnOnExplicitStrictfp(pos);
1457 }
1458 // Imply STRICTFP if owner has STRICTFP set.
1459 implicit |= sym.owner.flags_field & STRICTFP;
1460
1461 // primitive classes are implicitly final value classes.
1462 if ((flags & PRIMITIVE_CLASS) != 0)
1463 implicit |= VALUE_CLASS | FINAL;
1464
1465 // concrete value classes are implicitly final
1466 if ((flags & (ABSTRACT | INTERFACE | VALUE_CLASS)) == VALUE_CLASS)
1467 implicit |= FINAL;
1468
1469 // TYPs can't be declared synchronized
1470 mask &= ~SYNCHRONIZED;
1471 break;
1472 default:
1473 throw new AssertionError();
1474 }
1475 long illegal = flags & ExtendedStandardFlags & ~mask;
1476 if (illegal != 0) {
1477 if ((illegal & INTERFACE) != 0) {
1478 log.error(pos, ((flags & ANNOTATION) != 0) ? Errors.AnnotationDeclNotAllowedHere : Errors.IntfNotAllowedHere);
1479 mask |= INTERFACE;
1480 }
1481 else {
1482 log.error(pos,
1483 Errors.ModNotAllowedHere(asFlagSet(illegal)));
1484 }
1485 }
1486 else if ((sym.kind == TYP ||
1487 // ISSUE: Disallowing abstract&private is no longer appropriate
1488 // in the presence of inner classes. Should it be deleted here?
1489 checkDisjoint(pos, flags,
1490 ABSTRACT,
1491 PRIVATE | STATIC | DEFAULT))
1492 &&
1493 checkDisjoint(pos, flags,
1494 STATIC | PRIVATE,
1495 DEFAULT)
1496 &&
1497 checkDisjoint(pos, flags,
1498 ABSTRACT | INTERFACE,
1499 FINAL | NATIVE | SYNCHRONIZED | PRIMITIVE_CLASS)
1500 &&
1501 checkDisjoint(pos, flags,
1502 IDENTITY_TYPE,
1503 PRIMITIVE_CLASS | VALUE_CLASS)
1504 &&
1505 checkDisjoint(pos, flags,
1506 PUBLIC,
1507 PRIVATE | PROTECTED)
1508 &&
1509 checkDisjoint(pos, flags,
1510 PRIVATE,
1511 PUBLIC | PROTECTED)
1512 &&
1513 checkDisjoint(pos, (flags | implicit), // complain against volatile & implcitly final entities too.
1514 FINAL,
1515 VOLATILE)
1516 &&
1517 (sym.kind == TYP ||
1518 checkDisjoint(pos, flags,
1519 ABSTRACT | NATIVE,
1520 STRICTFP))
1521 && checkDisjoint(pos, flags,
1522 FINAL,
1523 SEALED | NON_SEALED)
1524 && checkDisjoint(pos, flags,
1525 SEALED,
1526 FINAL | NON_SEALED)
1527 && checkDisjoint(pos, flags,
1528 SEALED,
1529 ANNOTATION)) {
1530 // skip
1531 }
1532 return flags & (mask | ~ExtendedStandardFlags) | implicit;
1533 }
1534
1535 private void warnOnExplicitStrictfp(DiagnosticPosition pos) {
1536 DiagnosticPosition prevLintPos = deferredLintHandler.setPos(pos);
1537 try {
1538 deferredLintHandler.report(() -> {
1539 if (lint.isEnabled(LintCategory.STRICTFP)) {
1540 log.warning(LintCategory.STRICTFP,
1541 pos, Warnings.Strictfp); }
1542 });
1543 } finally {
1544 deferredLintHandler.setPos(prevLintPos);
1545 }
1546 }
1547
1548
1549 /** Determine if this enum should be implicitly final.
1550 *
1551 * If the enum has no specialized enum constants, it is final.
1552 *
1553 * If the enum does have specialized enum constants, it is
1554 * <i>not</i> final.
1555 */
1556 private long implicitEnumFinalFlag(JCTree tree) {
1557 if (!tree.hasTag(CLASSDEF)) return 0;
1558 class SpecialTreeVisitor extends JCTree.Visitor {
1559 boolean specialized;
1560 SpecialTreeVisitor() {
1561 this.specialized = false;
1562 }
1563
1564 @Override
1565 public void visitTree(JCTree tree) { /* no-op */ }
1566
1567 @Override
1568 public void visitVarDef(JCVariableDecl tree) {
1569 if ((tree.mods.flags & ENUM) != 0) {
1570 if (tree.init instanceof JCNewClass newClass && newClass.def != null) {
1571 specialized = true;
1572 }
1573 }
1574 }
1575 }
1576
1577 SpecialTreeVisitor sts = new SpecialTreeVisitor();
1578 JCClassDecl cdef = (JCClassDecl) tree;
1579 for (JCTree defs: cdef.defs) {
1580 defs.accept(sts);
1581 if (sts.specialized) return allowSealed ? SEALED : 0;
1582 }
1583 return FINAL;
1584 }
1585
1586 /* *************************************************************************
1587 * Type Validation
1588 **************************************************************************/
1589
1590 /** Validate a type expression. That is,
1591 * check that all type arguments of a parametric type are within
1592 * their bounds. This must be done in a second phase after type attribution
1593 * since a class might have a subclass as type parameter bound. E.g:
1594 *
1595 * <pre>{@code
1596 * class B<A extends C> { ... }
1597 * class C extends B<C> { ... }
1598 * }</pre>
1599 *
1600 * and we can't make sure that the bound is already attributed because
1601 * of possible cycles.
1602 *
1603 * Visitor method: Validate a type expression, if it is not null, catching
1604 * and reporting any completion failures.
1605 */
1606 void validate(JCTree tree, Env<AttrContext> env) {
1607 validate(tree, env, true);
1608 }
1609 void validate(JCTree tree, Env<AttrContext> env, boolean checkRaw) {
1610 new Validator(env).validateTree(tree, checkRaw, true);
1611 }
1612
1613 /** Visitor method: Validate a list of type expressions.
1614 */
1615 void validate(List<? extends JCTree> trees, Env<AttrContext> env) {
1616 for (List<? extends JCTree> l = trees; l.nonEmpty(); l = l.tail)
1617 validate(l.head, env);
1618 }
1619
1620 /** A visitor class for type validation.
1621 */
1622 class Validator extends JCTree.Visitor {
1623
1624 boolean checkRaw;
1625 boolean isOuter;
1626 Env<AttrContext> env;
1627
1628 Validator(Env<AttrContext> env) {
1629 this.env = env;
1630 }
1631
1632 @Override
1633 public void visitTypeArray(JCArrayTypeTree tree) {
1634 validateTree(tree.elemtype, checkRaw, isOuter);
1635 }
1636
1637 @Override
1638 public void visitTypeApply(JCTypeApply tree) {
1639 if (tree.type.hasTag(CLASS)) {
1640 List<JCExpression> args = tree.arguments;
1641 List<Type> forms = tree.type.tsym.type.getTypeArguments();
1642
1643 Type incompatibleArg = firstIncompatibleTypeArg(tree.type);
1644 if (incompatibleArg != null) {
1645 for (JCTree arg : tree.arguments) {
1646 if (arg.type == incompatibleArg) {
1647 log.error(arg, Errors.NotWithinBounds(incompatibleArg, forms.head));
1648 }
1649 forms = forms.tail;
1650 }
1651 }
1652
1653 forms = tree.type.tsym.type.getTypeArguments();
1654
1655 boolean is_java_lang_Class = tree.type.tsym.flatName() == names.java_lang_Class;
1656
1657 // For matching pairs of actual argument types `a' and
1658 // formal type parameters with declared bound `b' ...
1659 while (args.nonEmpty() && forms.nonEmpty()) {
1660 validateTree(args.head,
1661 !(isOuter && is_java_lang_Class),
1662 false);
1663 args = args.tail;
1664 forms = forms.tail;
1665 }
1666
1667 // Check that this type is either fully parameterized, or
1668 // not parameterized at all.
1669 if (tree.type.getEnclosingType().isRaw())
1670 log.error(tree.pos(), Errors.ImproperlyFormedTypeInnerRawParam);
1671 if (tree.clazz.hasTag(SELECT))
1672 visitSelectInternal((JCFieldAccess)tree.clazz);
1673 }
1674 }
1675
1676 @Override
1677 public void visitTypeParameter(JCTypeParameter tree) {
1678 validateTrees(tree.bounds, true, isOuter);
1679 checkClassBounds(tree.pos(), tree.type);
1680 }
1681
1682 @Override
1683 public void visitWildcard(JCWildcard tree) {
1684 if (tree.inner != null)
1685 validateTree(tree.inner, true, isOuter);
1686 }
1687
1688 @Override
1689 public void visitSelect(JCFieldAccess tree) {
1690 if (tree.type.hasTag(CLASS)) {
1691 visitSelectInternal(tree);
1692
1693 // Check that this type is either fully parameterized, or
1694 // not parameterized at all.
1695 if (tree.selected.type.isParameterized() && tree.type.tsym.type.getTypeArguments().nonEmpty())
1696 log.error(tree.pos(), Errors.ImproperlyFormedTypeParamMissing);
1697 }
1698 }
1699
1700 public void visitSelectInternal(JCFieldAccess tree) {
1701 if (tree.type.tsym.isStatic() &&
1702 tree.selected.type.isParameterized() &&
1703 (tree.name != names.ref || !tree.type.isReferenceProjection())) {
1704 // The enclosing type is not a class, so we are
1705 // looking at a static member type. However, the
1706 // qualifying expression is parameterized.
1707 // Tolerate the pseudo-select V.ref: V<T>.ref will be static if V<T> is and
1708 // should not be confused as selecting a static member of a parameterized type.
1709 log.error(tree.pos(), Errors.CantSelectStaticClassFromParamType);
1710 } else {
1711 // otherwise validate the rest of the expression
1712 tree.selected.accept(this);
1713 }
1714 }
1715
1716 @Override
1717 public void visitAnnotatedType(JCAnnotatedType tree) {
1718 tree.underlyingType.accept(this);
1719 }
1720
1721 @Override
1722 public void visitTypeIdent(JCPrimitiveTypeTree that) {
1723 if (that.type.hasTag(TypeTag.VOID)) {
1724 log.error(that.pos(), Errors.VoidNotAllowedHere);
1725 }
1726 super.visitTypeIdent(that);
1727 }
1728
1729 /** Default visitor method: do nothing.
1730 */
1731 @Override
1732 public void visitTree(JCTree tree) {
1733 }
1734
1735 public void validateTree(JCTree tree, boolean checkRaw, boolean isOuter) {
1736 if (tree != null) {
1737 boolean prevCheckRaw = this.checkRaw;
1738 this.checkRaw = checkRaw;
1739 this.isOuter = isOuter;
1740
1741 try {
1742 tree.accept(this);
1743 if (checkRaw)
1744 checkRaw(tree, env);
1745 } catch (CompletionFailure ex) {
1746 completionError(tree.pos(), ex);
1747 } finally {
1748 this.checkRaw = prevCheckRaw;
1749 }
1750 }
1751 }
1752
1753 public void validateTrees(List<? extends JCTree> trees, boolean checkRaw, boolean isOuter) {
1754 for (List<? extends JCTree> l = trees; l.nonEmpty(); l = l.tail)
1755 validateTree(l.head, checkRaw, isOuter);
1756 }
1757 }
1758
1759 void checkRaw(JCTree tree, Env<AttrContext> env) {
1760 if (lint.isEnabled(LintCategory.RAW) &&
1761 tree.type.hasTag(CLASS) &&
1762 !TreeInfo.isDiamond(tree) &&
1763 !withinAnonConstr(env) &&
1764 tree.type.isRaw()) {
1765 log.warning(LintCategory.RAW,
1766 tree.pos(), Warnings.RawClassUse(tree.type, tree.type.tsym.type));
1767 }
1768 }
1769 //where
1770 private boolean withinAnonConstr(Env<AttrContext> env) {
1771 return env.enclClass.name.isEmpty() &&
1772 env.enclMethod != null && env.enclMethod.name == names.init;
1773 }
1774
1775 /* *************************************************************************
1776 * Exception checking
1777 **************************************************************************/
1778
1779 /* The following methods treat classes as sets that contain
1780 * the class itself and all their subclasses
1781 */
1782
1783 /** Is given type a subtype of some of the types in given list?
1784 */
1785 boolean subset(Type t, List<Type> ts) {
1786 for (List<Type> l = ts; l.nonEmpty(); l = l.tail)
1787 if (types.isSubtype(t, l.head)) return true;
1788 return false;
1789 }
1790
1791 /** Is given type a subtype or supertype of
1792 * some of the types in given list?
1793 */
1794 boolean intersects(Type t, List<Type> ts) {
1795 for (List<Type> l = ts; l.nonEmpty(); l = l.tail)
1796 if (types.isSubtype(t, l.head) || types.isSubtype(l.head, t)) return true;
1797 return false;
1798 }
1799
1800 /** Add type set to given type list, unless it is a subclass of some class
1801 * in the list.
1802 */
1803 List<Type> incl(Type t, List<Type> ts) {
1804 return subset(t, ts) ? ts : excl(t, ts).prepend(t);
1805 }
1806
1807 /** Remove type set from type set list.
1808 */
1809 List<Type> excl(Type t, List<Type> ts) {
1810 if (ts.isEmpty()) {
1811 return ts;
1812 } else {
1813 List<Type> ts1 = excl(t, ts.tail);
1814 if (types.isSubtype(ts.head, t)) return ts1;
1815 else if (ts1 == ts.tail) return ts;
1816 else return ts1.prepend(ts.head);
1817 }
1818 }
1819
1820 /** Form the union of two type set lists.
1821 */
1822 List<Type> union(List<Type> ts1, List<Type> ts2) {
1823 List<Type> ts = ts1;
1824 for (List<Type> l = ts2; l.nonEmpty(); l = l.tail)
1825 ts = incl(l.head, ts);
1826 return ts;
1827 }
1828
1829 /** Form the difference of two type lists.
1830 */
1831 List<Type> diff(List<Type> ts1, List<Type> ts2) {
1832 List<Type> ts = ts1;
1833 for (List<Type> l = ts2; l.nonEmpty(); l = l.tail)
1834 ts = excl(l.head, ts);
1835 return ts;
1836 }
1837
1838 /** Form the intersection of two type lists.
1839 */
1840 public List<Type> intersect(List<Type> ts1, List<Type> ts2) {
1841 List<Type> ts = List.nil();
1842 for (List<Type> l = ts1; l.nonEmpty(); l = l.tail)
1843 if (subset(l.head, ts2)) ts = incl(l.head, ts);
1844 for (List<Type> l = ts2; l.nonEmpty(); l = l.tail)
1845 if (subset(l.head, ts1)) ts = incl(l.head, ts);
1846 return ts;
1847 }
1848
1849 /** Is exc an exception symbol that need not be declared?
1850 */
1851 boolean isUnchecked(ClassSymbol exc) {
1852 return
1853 exc.kind == ERR ||
1854 exc.isSubClass(syms.errorType.tsym, types) ||
1855 exc.isSubClass(syms.runtimeExceptionType.tsym, types);
1856 }
1857
1858 /** Is exc an exception type that need not be declared?
1859 */
1860 boolean isUnchecked(Type exc) {
1861 return
1862 (exc.hasTag(TYPEVAR)) ? isUnchecked(types.supertype(exc)) :
1863 (exc.hasTag(CLASS)) ? isUnchecked((ClassSymbol)exc.tsym) :
1864 exc.hasTag(BOT);
1865 }
1866
1867 boolean isChecked(Type exc) {
1868 return !isUnchecked(exc);
1869 }
1870
1871 /** Same, but handling completion failures.
1872 */
1873 boolean isUnchecked(DiagnosticPosition pos, Type exc) {
1874 try {
1875 return isUnchecked(exc);
1876 } catch (CompletionFailure ex) {
1877 completionError(pos, ex);
1878 return true;
1879 }
1880 }
1881
1882 /** Is exc handled by given exception list?
1883 */
1884 boolean isHandled(Type exc, List<Type> handled) {
1885 return isUnchecked(exc) || subset(exc, handled);
1886 }
1887
1888 /** Return all exceptions in thrown list that are not in handled list.
1889 * @param thrown The list of thrown exceptions.
1890 * @param handled The list of handled exceptions.
1891 */
1892 List<Type> unhandled(List<Type> thrown, List<Type> handled) {
1893 List<Type> unhandled = List.nil();
1894 for (List<Type> l = thrown; l.nonEmpty(); l = l.tail)
1895 if (!isHandled(l.head, handled)) unhandled = unhandled.prepend(l.head);
1896 return unhandled;
1897 }
1898
1899 /* *************************************************************************
1900 * Overriding/Implementation checking
1901 **************************************************************************/
1902
1903 /** The level of access protection given by a flag set,
1904 * where PRIVATE is highest and PUBLIC is lowest.
1905 */
1906 static int protection(long flags) {
1907 switch ((short)(flags & AccessFlags)) {
1908 case PRIVATE: return 3;
1909 case PROTECTED: return 1;
1910 default:
1911 case PUBLIC: return 0;
1912 case 0: return 2;
1913 }
1914 }
1915
1916 /** A customized "cannot override" error message.
1917 * @param m The overriding method.
1918 * @param other The overridden method.
1919 * @return An internationalized string.
1920 */
1921 Fragment cannotOverride(MethodSymbol m, MethodSymbol other) {
1922 Symbol mloc = m.location();
1923 Symbol oloc = other.location();
1924
1925 if ((other.owner.flags() & INTERFACE) == 0)
1926 return Fragments.CantOverride(m, mloc, other, oloc);
1927 else if ((m.owner.flags() & INTERFACE) == 0)
1928 return Fragments.CantImplement(m, mloc, other, oloc);
1929 else
1930 return Fragments.ClashesWith(m, mloc, other, oloc);
1931 }
1932
1933 /** A customized "override" warning message.
1934 * @param m The overriding method.
1935 * @param other The overridden method.
1936 * @return An internationalized string.
1937 */
1938 Fragment uncheckedOverrides(MethodSymbol m, MethodSymbol other) {
1939 Symbol mloc = m.location();
1940 Symbol oloc = other.location();
1941
1942 if ((other.owner.flags() & INTERFACE) == 0)
1943 return Fragments.UncheckedOverride(m, mloc, other, oloc);
1944 else if ((m.owner.flags() & INTERFACE) == 0)
1945 return Fragments.UncheckedImplement(m, mloc, other, oloc);
1946 else
1947 return Fragments.UncheckedClashWith(m, mloc, other, oloc);
1948 }
1949
1950 /** A customized "override" warning message.
1951 * @param m The overriding method.
1952 * @param other The overridden method.
1953 * @return An internationalized string.
1954 */
1955 Fragment varargsOverrides(MethodSymbol m, MethodSymbol other) {
1956 Symbol mloc = m.location();
1957 Symbol oloc = other.location();
1958
1959 if ((other.owner.flags() & INTERFACE) == 0)
1960 return Fragments.VarargsOverride(m, mloc, other, oloc);
1961 else if ((m.owner.flags() & INTERFACE) == 0)
1962 return Fragments.VarargsImplement(m, mloc, other, oloc);
1963 else
1964 return Fragments.VarargsClashWith(m, mloc, other, oloc);
1965 }
1966
1967 /** Check that this method conforms with overridden method 'other'.
1968 * where `origin' is the class where checking started.
1969 * Complications:
1970 * (1) Do not check overriding of synthetic methods
1971 * (reason: they might be final).
1972 * todo: check whether this is still necessary.
1973 * (2) Admit the case where an interface proxy throws fewer exceptions
1974 * than the method it implements. Augment the proxy methods with the
1975 * undeclared exceptions in this case.
1976 * (3) When generics are enabled, admit the case where an interface proxy
1977 * has a result type
1978 * extended by the result type of the method it implements.
1979 * Change the proxies result type to the smaller type in this case.
1980 *
1981 * @param tree The tree from which positions
1982 * are extracted for errors.
1983 * @param m The overriding method.
1984 * @param other The overridden method.
1985 * @param origin The class of which the overriding method
1986 * is a member.
1987 */
1988 void checkOverride(JCTree tree,
1989 MethodSymbol m,
1990 MethodSymbol other,
1991 ClassSymbol origin) {
1992 // Don't check overriding of synthetic methods or by bridge methods.
1993 if ((m.flags() & (SYNTHETIC|BRIDGE)) != 0 || (other.flags() & SYNTHETIC) != 0) {
1994 return;
1995 }
1996
1997 // Error if static method overrides instance method (JLS 8.4.8.2).
1998 if ((m.flags() & STATIC) != 0 &&
1999 (other.flags() & STATIC) == 0) {
2000 log.error(TreeInfo.diagnosticPositionFor(m, tree),
2001 Errors.OverrideStatic(cannotOverride(m, other)));
2002 m.flags_field |= BAD_OVERRIDE;
2003 return;
2004 }
2005
2006 // Error if instance method overrides static or final
2007 // method (JLS 8.4.8.1).
2008 if ((other.flags() & FINAL) != 0 ||
2009 (m.flags() & STATIC) == 0 &&
2010 (other.flags() & STATIC) != 0) {
2011 log.error(TreeInfo.diagnosticPositionFor(m, tree),
2012 Errors.OverrideMeth(cannotOverride(m, other),
2013 asFlagSet(other.flags() & (FINAL | STATIC))));
2014 m.flags_field |= BAD_OVERRIDE;
2015 return;
2016 }
2017
2018 if ((m.owner.flags() & ANNOTATION) != 0) {
2019 // handled in validateAnnotationMethod
2020 return;
2021 }
2022
2023 // Error if overriding method has weaker access (JLS 8.4.8.3).
2024 if (protection(m.flags()) > protection(other.flags())) {
2025 log.error(TreeInfo.diagnosticPositionFor(m, tree),
2026 (other.flags() & AccessFlags) == 0 ?
2027 Errors.OverrideWeakerAccess(cannotOverride(m, other),
2028 "package") :
2029 Errors.OverrideWeakerAccess(cannotOverride(m, other),
2030 asFlagSet(other.flags() & AccessFlags)));
2031 m.flags_field |= BAD_OVERRIDE;
2032 return;
2033 }
2034
2035 if (origin.isValueClass() && other.owner == syms.objectType.tsym && m.type.getParameterTypes().size() == 0) {
2036 if (m.name == names.finalize) {
2037 log.error(TreeInfo.diagnosticPositionFor(m, tree),
2038 Errors.ValueClassMayNotOverride(m.name));
2039 m.flags_field |= BAD_OVERRIDE;
2040 return;
2041 }
2042 }
2043
2044 Type mt = types.memberType(origin.type, m);
2045 Type ot = types.memberType(origin.type, other);
2046 // Error if overriding result type is different
2047 // (or, in the case of generics mode, not a subtype) of
2048 // overridden result type. We have to rename any type parameters
2049 // before comparing types.
2050 List<Type> mtvars = mt.getTypeArguments();
2051 List<Type> otvars = ot.getTypeArguments();
2052 Type mtres = mt.getReturnType();
2053 Type otres = types.subst(ot.getReturnType(), otvars, mtvars);
2054
2055 overrideWarner.clear();
2056 boolean resultTypesOK =
2057 types.returnTypeSubstitutable(mt, ot, otres, overrideWarner);
2058 if (!resultTypesOK) {
2059 if ((m.flags() & STATIC) != 0 && (other.flags() & STATIC) != 0) {
2060 log.error(TreeInfo.diagnosticPositionFor(m, tree),
2061 Errors.OverrideIncompatibleRet(Fragments.CantHide(m, m.location(), other,
2062 other.location()), mtres, otres));
2063 m.flags_field |= BAD_OVERRIDE;
2064 } else {
2065 log.error(TreeInfo.diagnosticPositionFor(m, tree),
2066 Errors.OverrideIncompatibleRet(cannotOverride(m, other), mtres, otres));
2067 m.flags_field |= BAD_OVERRIDE;
2068 }
2069 return;
2070 } else if (overrideWarner.hasNonSilentLint(LintCategory.UNCHECKED)) {
2071 warnUnchecked(TreeInfo.diagnosticPositionFor(m, tree),
2072 Warnings.OverrideUncheckedRet(uncheckedOverrides(m, other), mtres, otres));
2073 }
2074
2075 // Error if overriding method throws an exception not reported
2076 // by overridden method.
2077 List<Type> otthrown = types.subst(ot.getThrownTypes(), otvars, mtvars);
2078 List<Type> unhandledErased = unhandled(mt.getThrownTypes(), types.erasure(otthrown));
2079 List<Type> unhandledUnerased = unhandled(mt.getThrownTypes(), otthrown);
2080 if (unhandledErased.nonEmpty()) {
2081 log.error(TreeInfo.diagnosticPositionFor(m, tree),
2082 Errors.OverrideMethDoesntThrow(cannotOverride(m, other), unhandledUnerased.head));
2083 m.flags_field |= BAD_OVERRIDE;
2084 return;
2085 }
2086 else if (unhandledUnerased.nonEmpty()) {
2087 warnUnchecked(TreeInfo.diagnosticPositionFor(m, tree),
2088 Warnings.OverrideUncheckedThrown(cannotOverride(m, other), unhandledUnerased.head));
2089 return;
2090 }
2091
2092 // Optional warning if varargs don't agree
2093 if ((((m.flags() ^ other.flags()) & Flags.VARARGS) != 0)
2094 && lint.isEnabled(LintCategory.OVERRIDES)) {
2095 log.warning(TreeInfo.diagnosticPositionFor(m, tree),
2096 ((m.flags() & Flags.VARARGS) != 0)
2097 ? Warnings.OverrideVarargsMissing(varargsOverrides(m, other))
2098 : Warnings.OverrideVarargsExtra(varargsOverrides(m, other)));
2099 }
2100
2101 // Warn if instance method overrides bridge method (compiler spec ??)
2102 if ((other.flags() & BRIDGE) != 0) {
2103 log.warning(TreeInfo.diagnosticPositionFor(m, tree),
2104 Warnings.OverrideBridge(uncheckedOverrides(m, other)));
2105 }
2106
2107 // Warn if a deprecated method overridden by a non-deprecated one.
2108 if (!isDeprecatedOverrideIgnorable(other, origin)) {
2109 Lint prevLint = setLint(lint.augment(m));
2110 try {
2111 checkDeprecated(() -> TreeInfo.diagnosticPositionFor(m, tree), m, other);
2112 } finally {
2113 setLint(prevLint);
2114 }
2115 }
2116 }
2117 // where
2118 private boolean isDeprecatedOverrideIgnorable(MethodSymbol m, ClassSymbol origin) {
2119 // If the method, m, is defined in an interface, then ignore the issue if the method
2120 // is only inherited via a supertype and also implemented in the supertype,
2121 // because in that case, we will rediscover the issue when examining the method
2122 // in the supertype.
2123 // If the method, m, is not defined in an interface, then the only time we need to
2124 // address the issue is when the method is the supertype implementation: any other
2125 // case, we will have dealt with when examining the supertype classes
2126 ClassSymbol mc = m.enclClass();
2127 Type st = types.supertype(origin.type);
2128 if (!st.hasTag(CLASS))
2129 return true;
2130 MethodSymbol stimpl = m.implementation((ClassSymbol)st.tsym, types, false);
2131
2132 if (mc != null && ((mc.flags() & INTERFACE) != 0)) {
2133 List<Type> intfs = types.interfaces(origin.type);
2134 return (intfs.contains(mc.type) ? false : (stimpl != null));
2135 }
2136 else
2137 return (stimpl != m);
2138 }
2139
2140
2141 // used to check if there were any unchecked conversions
2142 Warner overrideWarner = new Warner();
2143
2144 /** Check that a class does not inherit two concrete methods
2145 * with the same signature.
2146 * @param pos Position to be used for error reporting.
2147 * @param site The class type to be checked.
2148 */
2149 public void checkCompatibleConcretes(DiagnosticPosition pos, Type site) {
2150 Type sup = types.supertype(site);
2151 if (!sup.hasTag(CLASS)) return;
2152
2153 for (Type t1 = sup;
2154 t1.hasTag(CLASS) && t1.tsym.type.isParameterized();
2155 t1 = types.supertype(t1)) {
2156 for (Symbol s1 : t1.tsym.members().getSymbols(NON_RECURSIVE)) {
2157 if (s1.kind != MTH ||
2158 (s1.flags() & (STATIC|SYNTHETIC|BRIDGE)) != 0 ||
2159 !s1.isInheritedIn(site.tsym, types) ||
2160 ((MethodSymbol)s1).implementation(site.tsym,
2161 types,
2162 true) != s1)
2163 continue;
2164 Type st1 = types.memberType(t1, s1);
2165 int s1ArgsLength = st1.getParameterTypes().length();
2166 if (st1 == s1.type) continue;
2167
2168 for (Type t2 = sup;
2169 t2.hasTag(CLASS);
2170 t2 = types.supertype(t2)) {
2171 for (Symbol s2 : t2.tsym.members().getSymbolsByName(s1.name)) {
2172 if (s2 == s1 ||
2173 s2.kind != MTH ||
2174 (s2.flags() & (STATIC|SYNTHETIC|BRIDGE)) != 0 ||
2175 s2.type.getParameterTypes().length() != s1ArgsLength ||
2176 !s2.isInheritedIn(site.tsym, types) ||
2177 ((MethodSymbol)s2).implementation(site.tsym,
2178 types,
2179 true) != s2)
2180 continue;
2181 Type st2 = types.memberType(t2, s2);
2182 if (types.overrideEquivalent(st1, st2))
2183 log.error(pos,
2184 Errors.ConcreteInheritanceConflict(s1, t1, s2, t2, sup));
2185 }
2186 }
2187 }
2188 }
2189 }
2190
2191 /** Check that classes (or interfaces) do not each define an abstract
2192 * method with same name and arguments but incompatible return types.
2193 * @param pos Position to be used for error reporting.
2194 * @param t1 The first argument type.
2195 * @param t2 The second argument type.
2196 */
2197 public boolean checkCompatibleAbstracts(DiagnosticPosition pos,
2198 Type t1,
2199 Type t2,
2200 Type site) {
2201 if ((site.tsym.flags() & COMPOUND) != 0) {
2202 // special case for intersections: need to eliminate wildcards in supertypes
2203 t1 = types.capture(t1);
2204 t2 = types.capture(t2);
2205 }
2206 return firstIncompatibility(pos, t1, t2, site) == null;
2207 }
2208
2209 /** Return the first method which is defined with same args
2210 * but different return types in two given interfaces, or null if none
2211 * exists.
2212 * @param t1 The first type.
2213 * @param t2 The second type.
2214 * @param site The most derived type.
2215 * @return symbol from t2 that conflicts with one in t1.
2216 */
2217 private Symbol firstIncompatibility(DiagnosticPosition pos, Type t1, Type t2, Type site) {
2218 Map<TypeSymbol,Type> interfaces1 = new HashMap<>();
2219 closure(t1, interfaces1);
2220 Map<TypeSymbol,Type> interfaces2;
2221 if (t1 == t2)
2222 interfaces2 = interfaces1;
2223 else
2224 closure(t2, interfaces1, interfaces2 = new HashMap<>());
2225
2226 for (Type t3 : interfaces1.values()) {
2227 for (Type t4 : interfaces2.values()) {
2228 Symbol s = firstDirectIncompatibility(pos, t3, t4, site);
2229 if (s != null) return s;
2230 }
2231 }
2232 return null;
2233 }
2234
2235 /** Compute all the supertypes of t, indexed by type symbol. */
2236 private void closure(Type t, Map<TypeSymbol,Type> typeMap) {
2237 if (!t.hasTag(CLASS)) return;
2238 if (typeMap.put(t.tsym, t) == null) {
2239 closure(types.supertype(t), typeMap);
2240 for (Type i : types.interfaces(t))
2241 closure(i, typeMap);
2242 }
2243 }
2244
2245 /** Compute all the supertypes of t, indexed by type symbol (except those in typesSkip). */
2246 private void closure(Type t, Map<TypeSymbol,Type> typesSkip, Map<TypeSymbol,Type> typeMap) {
2247 if (!t.hasTag(CLASS)) return;
2248 if (typesSkip.get(t.tsym) != null) return;
2249 if (typeMap.put(t.tsym, t) == null) {
2250 closure(types.supertype(t), typesSkip, typeMap);
2251 for (Type i : types.interfaces(t))
2252 closure(i, typesSkip, typeMap);
2253 }
2254 }
2255
2256 /** Return the first method in t2 that conflicts with a method from t1. */
2257 private Symbol firstDirectIncompatibility(DiagnosticPosition pos, Type t1, Type t2, Type site) {
2258 for (Symbol s1 : t1.tsym.members().getSymbols(NON_RECURSIVE)) {
2259 Type st1 = null;
2260 if (s1.kind != MTH || !s1.isInheritedIn(site.tsym, types) ||
2261 (s1.flags() & SYNTHETIC) != 0) continue;
2262 Symbol impl = ((MethodSymbol)s1).implementation(site.tsym, types, false);
2263 if (impl != null && (impl.flags() & ABSTRACT) == 0) continue;
2264 for (Symbol s2 : t2.tsym.members().getSymbolsByName(s1.name)) {
2265 if (s1 == s2) continue;
2266 if (s2.kind != MTH || !s2.isInheritedIn(site.tsym, types) ||
2267 (s2.flags() & SYNTHETIC) != 0) continue;
2268 if (st1 == null) st1 = types.memberType(t1, s1);
2269 Type st2 = types.memberType(t2, s2);
2270 if (types.overrideEquivalent(st1, st2)) {
2271 List<Type> tvars1 = st1.getTypeArguments();
2272 List<Type> tvars2 = st2.getTypeArguments();
2273 Type rt1 = st1.getReturnType();
2274 Type rt2 = types.subst(st2.getReturnType(), tvars2, tvars1);
2275 boolean compat =
2276 types.isSameType(rt1, rt2) ||
2277 !rt1.isPrimitiveOrVoid() &&
2278 !rt2.isPrimitiveOrVoid() &&
2279 (types.covariantReturnType(rt1, rt2, types.noWarnings) ||
2280 types.covariantReturnType(rt2, rt1, types.noWarnings)) ||
2281 checkCommonOverriderIn(s1,s2,site);
2282 if (!compat) {
2283 log.error(pos, Errors.TypesIncompatible(t1, t2,
2284 Fragments.IncompatibleDiffRet(s2.name, types.memberType(t2, s2).getParameterTypes())));
2285 return s2;
2286 }
2287 } else if (checkNameClash((ClassSymbol)site.tsym, s1, s2) &&
2288 !checkCommonOverriderIn(s1, s2, site)) {
2289 log.error(pos, Errors.NameClashSameErasureNoOverride(
2290 s1.name, types.memberType(site, s1).asMethodType().getParameterTypes(), s1.location(),
2291 s2.name, types.memberType(site, s2).asMethodType().getParameterTypes(), s2.location()));
2292 return s2;
2293 }
2294 }
2295 }
2296 return null;
2297 }
2298 //WHERE
2299 boolean checkCommonOverriderIn(Symbol s1, Symbol s2, Type site) {
2300 Map<TypeSymbol,Type> supertypes = new HashMap<>();
2301 Type st1 = types.memberType(site, s1);
2302 Type st2 = types.memberType(site, s2);
2303 closure(site, supertypes);
2304 for (Type t : supertypes.values()) {
2305 for (Symbol s3 : t.tsym.members().getSymbolsByName(s1.name)) {
2306 if (s3 == s1 || s3 == s2 || s3.kind != MTH || (s3.flags() & (BRIDGE|SYNTHETIC)) != 0) continue;
2307 Type st3 = types.memberType(site,s3);
2308 if (types.overrideEquivalent(st3, st1) &&
2309 types.overrideEquivalent(st3, st2) &&
2310 types.returnTypeSubstitutable(st3, st1) &&
2311 types.returnTypeSubstitutable(st3, st2)) {
2312 return true;
2313 }
2314 }
2315 }
2316 return false;
2317 }
2318
2319 /** Check that a given method conforms with any method it overrides.
2320 * @param tree The tree from which positions are extracted
2321 * for errors.
2322 * @param m The overriding method.
2323 */
2324 void checkOverride(Env<AttrContext> env, JCMethodDecl tree, MethodSymbol m) {
2325 ClassSymbol origin = (ClassSymbol)m.owner;
2326 if ((origin.flags() & ENUM) != 0 && names.finalize.equals(m.name)) {
2327 if (m.overrides(syms.enumFinalFinalize, origin, types, false)) {
2328 log.error(tree.pos(), Errors.EnumNoFinalize);
2329 return;
2330 }
2331 }
2332 if (allowRecords && origin.isRecord()) {
2333 // let's find out if this is a user defined accessor in which case the @Override annotation is acceptable
2334 Optional<? extends RecordComponent> recordComponent = origin.getRecordComponents().stream()
2335 .filter(rc -> rc.accessor == tree.sym && (rc.accessor.flags_field & GENERATED_MEMBER) == 0).findFirst();
2336 if (recordComponent.isPresent()) {
2337 return;
2338 }
2339 }
2340
2341 for (Type t = origin.type; t.hasTag(CLASS);
2342 t = types.supertype(t)) {
2343 if (t != origin.type) {
2344 checkOverride(tree, t, origin, m);
2345 }
2346 for (Type t2 : types.interfaces(t)) {
2347 checkOverride(tree, t2, origin, m);
2348 }
2349 }
2350
2351 final boolean explicitOverride = m.attribute(syms.overrideType.tsym) != null;
2352 // Check if this method must override a super method due to being annotated with @Override
2353 // or by virtue of being a member of a diamond inferred anonymous class. Latter case is to
2354 // be treated "as if as they were annotated" with @Override.
2355 boolean mustOverride = explicitOverride ||
2356 (env.info.isAnonymousDiamond && !m.isConstructor() && !m.isPrivate());
2357 if (mustOverride && !isOverrider(m)) {
2358 DiagnosticPosition pos = tree.pos();
2359 for (JCAnnotation a : tree.getModifiers().annotations) {
2360 if (a.annotationType.type.tsym == syms.overrideType.tsym) {
2361 pos = a.pos();
2362 break;
2363 }
2364 }
2365 log.error(pos,
2366 explicitOverride ? (m.isStatic() ? Errors.StaticMethodsCannotBeAnnotatedWithOverride : Errors.MethodDoesNotOverrideSuperclass) :
2367 Errors.AnonymousDiamondMethodDoesNotOverrideSuperclass(Fragments.DiamondAnonymousMethodsImplicitlyOverride));
2368 }
2369 }
2370
2371 void checkOverride(JCTree tree, Type site, ClassSymbol origin, MethodSymbol m) {
2372 TypeSymbol c = site.tsym;
2373 for (Symbol sym : c.members().getSymbolsByName(m.name)) {
2374 if (m.overrides(sym, origin, types, false)) {
2375 if ((sym.flags() & ABSTRACT) == 0) {
2376 checkOverride(tree, m, (MethodSymbol)sym, origin);
2377 }
2378 }
2379 }
2380 }
2381
2382 private Predicate<Symbol> equalsHasCodeFilter = s -> MethodSymbol.implementation_filter.test(s) &&
2383 (s.flags() & BAD_OVERRIDE) == 0;
2384
2385 public void checkClassOverrideEqualsAndHashIfNeeded(DiagnosticPosition pos,
2386 ClassSymbol someClass) {
2387 /* At present, annotations cannot possibly have a method that is override
2388 * equivalent with Object.equals(Object) but in any case the condition is
2389 * fine for completeness.
2390 */
2391 if (someClass == (ClassSymbol)syms.objectType.tsym ||
2392 someClass.isInterface() || someClass.isEnum() ||
2393 (someClass.flags() & ANNOTATION) != 0 ||
2394 (someClass.flags() & ABSTRACT) != 0) return;
2395 //anonymous inner classes implementing interfaces need especial treatment
2396 if (someClass.isAnonymous()) {
2397 List<Type> interfaces = types.interfaces(someClass.type);
2398 if (interfaces != null && !interfaces.isEmpty() &&
2399 interfaces.head.tsym == syms.comparatorType.tsym) return;
2400 }
2401 checkClassOverrideEqualsAndHash(pos, someClass);
2402 }
2403
2404 private void checkClassOverrideEqualsAndHash(DiagnosticPosition pos,
2405 ClassSymbol someClass) {
2406 if (lint.isEnabled(LintCategory.OVERRIDES)) {
2407 MethodSymbol equalsAtObject = (MethodSymbol)syms.objectType
2408 .tsym.members().findFirst(names.equals);
2409 MethodSymbol hashCodeAtObject = (MethodSymbol)syms.objectType
2410 .tsym.members().findFirst(names.hashCode);
2411 MethodSymbol equalsImpl = types.implementation(equalsAtObject,
2412 someClass, false, equalsHasCodeFilter);
2413 boolean overridesEquals = equalsImpl != null &&
2414 equalsImpl.owner == someClass;
2415 boolean overridesHashCode = types.implementation(hashCodeAtObject,
2416 someClass, false, equalsHasCodeFilter) != hashCodeAtObject;
2417
2418 if (overridesEquals && !overridesHashCode) {
2419 log.warning(LintCategory.OVERRIDES, pos,
2420 Warnings.OverrideEqualsButNotHashcode(someClass));
2421 }
2422 }
2423 }
2424
2425 public void checkModuleName (JCModuleDecl tree) {
2426 Name moduleName = tree.sym.name;
2427 Assert.checkNonNull(moduleName);
2428 if (lint.isEnabled(LintCategory.MODULE)) {
2429 JCExpression qualId = tree.qualId;
2430 while (qualId != null) {
2431 Name componentName;
2432 DiagnosticPosition pos;
2433 switch (qualId.getTag()) {
2434 case SELECT:
2435 JCFieldAccess selectNode = ((JCFieldAccess) qualId);
2436 componentName = selectNode.name;
2437 pos = selectNode.pos();
2438 qualId = selectNode.selected;
2439 break;
2440 case IDENT:
2441 componentName = ((JCIdent) qualId).name;
2442 pos = qualId.pos();
2443 qualId = null;
2444 break;
2445 default:
2446 throw new AssertionError("Unexpected qualified identifier: " + qualId.toString());
2447 }
2448 if (componentName != null) {
2449 String moduleNameComponentString = componentName.toString();
2450 int nameLength = moduleNameComponentString.length();
2451 if (nameLength > 0 && Character.isDigit(moduleNameComponentString.charAt(nameLength - 1))) {
2452 log.warning(Lint.LintCategory.MODULE, pos, Warnings.PoorChoiceForModuleName(componentName));
2453 }
2454 }
2455 }
2456 }
2457 }
2458
2459 private boolean checkNameClash(ClassSymbol origin, Symbol s1, Symbol s2) {
2460 ClashFilter cf = new ClashFilter(origin.type);
2461 return (cf.test(s1) &&
2462 cf.test(s2) &&
2463 types.hasSameArgs(s1.erasure(types), s2.erasure(types)));
2464 }
2465
2466
2467 /** Check that all abstract members of given class have definitions.
2468 * @param pos Position to be used for error reporting.
2469 * @param c The class.
2470 */
2471 void checkAllDefined(DiagnosticPosition pos, ClassSymbol c) {
2472 MethodSymbol undef = types.firstUnimplementedAbstract(c);
2473 if (undef != null) {
2474 MethodSymbol undef1 =
2475 new MethodSymbol(undef.flags(), undef.name,
2476 types.memberType(c.type, undef), undef.owner);
2477 log.error(pos,
2478 Errors.DoesNotOverrideAbstract(c, undef1, undef1.location()));
2479 }
2480 }
2481
2482 // A primitive class cannot contain a field of its own type either or indirectly.
2483 void checkNonCyclicMembership(JCClassDecl tree) {
2484 Assert.check((tree.sym.flags_field & LOCKED) == 0);
2485 try {
2486 tree.sym.flags_field |= LOCKED;
2487 for (List<? extends JCTree> l = tree.defs; l.nonEmpty(); l = l.tail) {
2488 if (l.head.hasTag(VARDEF)) {
2489 JCVariableDecl field = (JCVariableDecl) l.head;
2490 if (cyclePossible(field.sym)) {
2491 checkNonCyclicMembership((ClassSymbol) field.type.tsym, field.pos());
2492 }
2493 }
2494 }
2495 } finally {
2496 tree.sym.flags_field &= ~LOCKED;
2497 }
2498
2499 }
2500 // where
2501 private void checkNonCyclicMembership(ClassSymbol c, DiagnosticPosition pos) {
2502 if ((c.flags_field & LOCKED) != 0) {
2503 log.error(pos, Errors.CyclicPrimitiveClassMembership(c));
2504 return;
2505 }
2506 try {
2507 c.flags_field |= LOCKED;
2508 for (Symbol fld : c.members().getSymbols(s -> s.kind == VAR && cyclePossible((VarSymbol) s), NON_RECURSIVE)) {
2509 checkNonCyclicMembership((ClassSymbol) fld.type.tsym, pos);
2510 }
2511 } finally {
2512 c.flags_field &= ~LOCKED;
2513 }
2514 }
2515 // where
2516 private boolean cyclePossible(VarSymbol symbol) {
2517 return (symbol.flags() & STATIC) == 0 && symbol.type.isPrimitiveClass();
2518 }
2519
2520 void checkNonCyclicDecl(JCClassDecl tree) {
2521 CycleChecker cc = new CycleChecker();
2522 cc.scan(tree);
2523 if (!cc.errorFound && !cc.partialCheck) {
2524 tree.sym.flags_field |= ACYCLIC;
2525 }
2526 }
2527
2528 class CycleChecker extends TreeScanner {
2529
2530 Set<Symbol> seenClasses = new HashSet<>();
2531 boolean errorFound = false;
2532 boolean partialCheck = false;
2533
2534 private void checkSymbol(DiagnosticPosition pos, Symbol sym) {
2535 if (sym != null && sym.kind == TYP) {
2536 Env<AttrContext> classEnv = enter.getEnv((TypeSymbol)sym);
2537 if (classEnv != null) {
2538 DiagnosticSource prevSource = log.currentSource();
2539 try {
2540 log.useSource(classEnv.toplevel.sourcefile);
2541 scan(classEnv.tree);
2542 }
2543 finally {
2544 log.useSource(prevSource.getFile());
2545 }
2546 } else if (sym.kind == TYP) {
2547 checkClass(pos, sym, List.nil());
2548 }
2549 } else if (sym == null || sym.kind != PCK) {
2550 //not completed yet
2551 partialCheck = true;
2552 }
2553 }
2554
2555 @Override
2556 public void visitSelect(JCFieldAccess tree) {
2557 super.visitSelect(tree);
2558 checkSymbol(tree.pos(), tree.sym);
2559 }
2560
2561 @Override
2562 public void visitIdent(JCIdent tree) {
2563 checkSymbol(tree.pos(), tree.sym);
2564 }
2565
2566 @Override
2567 public void visitTypeApply(JCTypeApply tree) {
2568 scan(tree.clazz);
2569 }
2570
2571 @Override
2572 public void visitTypeArray(JCArrayTypeTree tree) {
2573 scan(tree.elemtype);
2574 }
2575
2576 @Override
2577 public void visitClassDef(JCClassDecl tree) {
2578 List<JCTree> supertypes = List.nil();
2579 if (tree.getExtendsClause() != null) {
2580 supertypes = supertypes.prepend(tree.getExtendsClause());
2581 }
2582 if (tree.getImplementsClause() != null) {
2583 for (JCTree intf : tree.getImplementsClause()) {
2584 supertypes = supertypes.prepend(intf);
2585 }
2586 }
2587 checkClass(tree.pos(), tree.sym, supertypes);
2588 }
2589
2590 void checkClass(DiagnosticPosition pos, Symbol c, List<JCTree> supertypes) {
2591 if ((c.flags_field & ACYCLIC) != 0)
2592 return;
2593 if (seenClasses.contains(c)) {
2594 errorFound = true;
2595 noteCyclic(pos, (ClassSymbol)c);
2596 } else if (!c.type.isErroneous()) {
2597 try {
2598 seenClasses.add(c);
2599 if (c.type.hasTag(CLASS)) {
2600 if (supertypes.nonEmpty()) {
2601 scan(supertypes);
2602 }
2603 else {
2604 ClassType ct = (ClassType)c.type;
2605 if (ct.supertype_field == null ||
2606 ct.interfaces_field == null) {
2607 //not completed yet
2608 partialCheck = true;
2609 return;
2610 }
2611 checkSymbol(pos, ct.supertype_field.tsym);
2612 for (Type intf : ct.interfaces_field) {
2613 checkSymbol(pos, intf.tsym);
2614 }
2615 }
2616 if (c.owner.kind == TYP) {
2617 checkSymbol(pos, c.owner);
2618 }
2619 }
2620 } finally {
2621 seenClasses.remove(c);
2622 }
2623 }
2624 }
2625 }
2626
2627 /** Check for cyclic references. Issue an error if the
2628 * symbol of the type referred to has a LOCKED flag set.
2629 *
2630 * @param pos Position to be used for error reporting.
2631 * @param t The type referred to.
2632 */
2633 void checkNonCyclic(DiagnosticPosition pos, Type t) {
2634 checkNonCyclicInternal(pos, t);
2635 }
2636
2637
2638 void checkNonCyclic(DiagnosticPosition pos, TypeVar t) {
2639 checkNonCyclic1(pos, t, List.nil());
2640 }
2641
2642 private void checkNonCyclic1(DiagnosticPosition pos, Type t, List<TypeVar> seen) {
2643 final TypeVar tv;
2644 if (t.hasTag(TYPEVAR) && (t.tsym.flags() & UNATTRIBUTED) != 0)
2645 return;
2646 if (seen.contains(t)) {
2647 tv = (TypeVar)t;
2648 tv.setUpperBound(types.createErrorType(t));
2649 log.error(pos, Errors.CyclicInheritance(t));
2650 } else if (t.hasTag(TYPEVAR)) {
2651 tv = (TypeVar)t;
2652 seen = seen.prepend(tv);
2653 for (Type b : types.getBounds(tv))
2654 checkNonCyclic1(pos, b, seen);
2655 }
2656 }
2657
2658 /** Check for cyclic references. Issue an error if the
2659 * symbol of the type referred to has a LOCKED flag set.
2660 *
2661 * @param pos Position to be used for error reporting.
2662 * @param t The type referred to.
2663 * @returns True if the check completed on all attributed classes
2664 */
2665 private boolean checkNonCyclicInternal(DiagnosticPosition pos, Type t) {
2666 boolean complete = true; // was the check complete?
2667 //- System.err.println("checkNonCyclicInternal("+t+");");//DEBUG
2668 Symbol c = t.tsym;
2669 if ((c.flags_field & ACYCLIC) != 0) return true;
2670
2671 if ((c.flags_field & LOCKED) != 0) {
2672 noteCyclic(pos, (ClassSymbol)c);
2673 } else if (!c.type.isErroneous()) {
2674 try {
2675 c.flags_field |= LOCKED;
2676 if (c.type.hasTag(CLASS)) {
2677 ClassType clazz = (ClassType)c.type;
2678 if (clazz.interfaces_field != null)
2679 for (List<Type> l=clazz.interfaces_field; l.nonEmpty(); l=l.tail)
2680 complete &= checkNonCyclicInternal(pos, l.head);
2681 if (clazz.supertype_field != null) {
2682 Type st = clazz.supertype_field;
2683 if (st != null && st.hasTag(CLASS))
2684 complete &= checkNonCyclicInternal(pos, st);
2685 }
2686 if (c.owner.kind == TYP)
2687 complete &= checkNonCyclicInternal(pos, c.owner.type);
2688 }
2689 } finally {
2690 c.flags_field &= ~LOCKED;
2691 }
2692 }
2693 if (complete)
2694 complete = ((c.flags_field & UNATTRIBUTED) == 0) && c.isCompleted();
2695 if (complete) c.flags_field |= ACYCLIC;
2696 return complete;
2697 }
2698
2699 /** Note that we found an inheritance cycle. */
2700 private void noteCyclic(DiagnosticPosition pos, ClassSymbol c) {
2701 log.error(pos, Errors.CyclicInheritance(c));
2702 for (List<Type> l=types.interfaces(c.type); l.nonEmpty(); l=l.tail)
2703 l.head = types.createErrorType((ClassSymbol)l.head.tsym, Type.noType);
2704 Type st = types.supertype(c.type);
2705 if (st.hasTag(CLASS))
2706 ((ClassType)c.type).supertype_field = types.createErrorType((ClassSymbol)st.tsym, Type.noType);
2707 c.type = types.createErrorType(c, c.type);
2708 c.flags_field |= ACYCLIC;
2709 }
2710
2711 /** Check that all methods which implement some
2712 * method conform to the method they implement.
2713 * @param tree The class definition whose members are checked.
2714 */
2715 void checkImplementations(JCClassDecl tree) {
2716 checkImplementations(tree, tree.sym, tree.sym);
2717 }
2718 //where
2719 /** Check that all methods which implement some
2720 * method in `ic' conform to the method they implement.
2721 */
2722 void checkImplementations(JCTree tree, ClassSymbol origin, ClassSymbol ic) {
2723 for (List<Type> l = types.closure(ic.type); l.nonEmpty(); l = l.tail) {
2724 ClassSymbol lc = (ClassSymbol)l.head.tsym;
2725 if ((lc.flags() & ABSTRACT) != 0) {
2726 for (Symbol sym : lc.members().getSymbols(NON_RECURSIVE)) {
2727 if (sym.kind == MTH &&
2728 (sym.flags() & (STATIC|ABSTRACT)) == ABSTRACT) {
2729 MethodSymbol absmeth = (MethodSymbol)sym;
2730 MethodSymbol implmeth = absmeth.implementation(origin, types, false);
2731 if (implmeth != null && implmeth != absmeth &&
2732 (implmeth.owner.flags() & INTERFACE) ==
2733 (origin.flags() & INTERFACE)) {
2734 // don't check if implmeth is in a class, yet
2735 // origin is an interface. This case arises only
2736 // if implmeth is declared in Object. The reason is
2737 // that interfaces really don't inherit from
2738 // Object it's just that the compiler represents
2739 // things that way.
2740 checkOverride(tree, implmeth, absmeth, origin);
2741 }
2742 }
2743 }
2744 }
2745 }
2746 }
2747
2748 /** Check that all abstract methods implemented by a class are
2749 * mutually compatible.
2750 * @param pos Position to be used for error reporting.
2751 * @param c The class whose interfaces are checked.
2752 */
2753 void checkCompatibleSupertypes(DiagnosticPosition pos, Type c) {
2754 List<Type> supertypes = types.interfaces(c);
2755 Type supertype = types.supertype(c);
2756 if (supertype.hasTag(CLASS) &&
2757 (supertype.tsym.flags() & ABSTRACT) != 0)
2758 supertypes = supertypes.prepend(supertype);
2759 for (List<Type> l = supertypes; l.nonEmpty(); l = l.tail) {
2760 if (!l.head.getTypeArguments().isEmpty() &&
2761 !checkCompatibleAbstracts(pos, l.head, l.head, c))
2762 return;
2763 for (List<Type> m = supertypes; m != l; m = m.tail)
2764 if (!checkCompatibleAbstracts(pos, l.head, m.head, c))
2765 return;
2766 }
2767 checkCompatibleConcretes(pos, c);
2768
2769 boolean cIsValue = (c.tsym.flags() & VALUE_CLASS) != 0;
2770 boolean cHasIdentity = (c.tsym.flags() & IDENTITY_TYPE) != 0;
2771 Type identitySuper = null, valueSuper = null;
2772 for (Type t : types.closure(c)) {
2773 if (t != c) {
2774 if ((t.tsym.flags() & IDENTITY_TYPE) != 0)
2775 identitySuper = t;
2776 else if ((t.tsym.flags() & VALUE_CLASS) != 0)
2777 valueSuper = t;
2778 if (cIsValue && identitySuper != null) {
2779 log.error(pos, Errors.ValueTypeHasIdentitySuperType(c, identitySuper));
2780 break;
2781 } else if (cHasIdentity && valueSuper != null) {
2782 log.error(pos, Errors.IdentityTypeHasValueSuperType(c, valueSuper));
2783 break;
2784 } else if (identitySuper != null && valueSuper != null) {
2785 log.error(pos, Errors.MutuallyIncompatibleSupers(c, identitySuper, valueSuper));
2786 break;
2787 }
2788 }
2789 }
2790 }
2791
2792 /** Check that all non-override equivalent methods accessible from 'site'
2793 * are mutually compatible (JLS 8.4.8/9.4.1).
2794 *
2795 * @param pos Position to be used for error reporting.
2796 * @param site The class whose methods are checked.
2797 * @param sym The method symbol to be checked.
2798 */
2799 void checkOverrideClashes(DiagnosticPosition pos, Type site, MethodSymbol sym) {
2800 ClashFilter cf = new ClashFilter(site);
2801 //for each method m1 that is overridden (directly or indirectly)
2802 //by method 'sym' in 'site'...
2803
2804 List<MethodSymbol> potentiallyAmbiguousList = List.nil();
2805 boolean overridesAny = false;
2806 ArrayList<Symbol> symbolsByName = new ArrayList<>();
2807 types.membersClosure(site, false).getSymbolsByName(sym.name, cf).forEach(symbolsByName::add);
2808 for (Symbol m1 : symbolsByName) {
2809 if (!sym.overrides(m1, site.tsym, types, false)) {
2810 if (m1 == sym) {
2811 continue;
2812 }
2813
2814 if (!overridesAny) {
2815 potentiallyAmbiguousList = potentiallyAmbiguousList.prepend((MethodSymbol)m1);
2816 }
2817 continue;
2818 }
2819
2820 if (m1 != sym) {
2821 overridesAny = true;
2822 potentiallyAmbiguousList = List.nil();
2823 }
2824
2825 //...check each method m2 that is a member of 'site'
2826 for (Symbol m2 : symbolsByName) {
2827 if (m2 == m1) continue;
2828 //if (i) the signature of 'sym' is not a subsignature of m1 (seen as
2829 //a member of 'site') and (ii) m1 has the same erasure as m2, issue an error
2830 if (!types.isSubSignature(sym.type, types.memberType(site, m2), Feature.STRICT_METHOD_CLASH_CHECK.allowedInSource(source)) &&
2831 types.hasSameArgs(m2.erasure(types), m1.erasure(types))) {
2832 sym.flags_field |= CLASH;
2833 if (m1 == sym) {
2834 log.error(pos, Errors.NameClashSameErasureNoOverride(
2835 m1.name, types.memberType(site, m1).asMethodType().getParameterTypes(), m1.location(),
2836 m2.name, types.memberType(site, m2).asMethodType().getParameterTypes(), m2.location()));
2837 } else {
2838 ClassType ct = (ClassType)site;
2839 String kind = ct.isInterface() ? "interface" : "class";
2840 log.error(pos, Errors.NameClashSameErasureNoOverride1(
2841 kind,
2842 ct.tsym.name,
2843 m1.name,
2844 types.memberType(site, m1).asMethodType().getParameterTypes(),
2845 m1.location(),
2846 m2.name,
2847 types.memberType(site, m2).asMethodType().getParameterTypes(),
2848 m2.location()));
2849 }
2850 return;
2851 }
2852 }
2853 }
2854
2855 if (!overridesAny) {
2856 for (MethodSymbol m: potentiallyAmbiguousList) {
2857 checkPotentiallyAmbiguousOverloads(pos, site, sym, m);
2858 }
2859 }
2860 }
2861
2862 /** Check that all static methods accessible from 'site' are
2863 * mutually compatible (JLS 8.4.8).
2864 *
2865 * @param pos Position to be used for error reporting.
2866 * @param site The class whose methods are checked.
2867 * @param sym The method symbol to be checked.
2868 */
2869 void checkHideClashes(DiagnosticPosition pos, Type site, MethodSymbol sym) {
2870 ClashFilter cf = new ClashFilter(site);
2871 //for each method m1 that is a member of 'site'...
2872 for (Symbol s : types.membersClosure(site, true).getSymbolsByName(sym.name, cf)) {
2873 //if (i) the signature of 'sym' is not a subsignature of m1 (seen as
2874 //a member of 'site') and (ii) 'sym' has the same erasure as m1, issue an error
2875 if (!types.isSubSignature(sym.type, types.memberType(site, s), Feature.STRICT_METHOD_CLASH_CHECK.allowedInSource(source))) {
2876 if (types.hasSameArgs(s.erasure(types), sym.erasure(types))) {
2877 log.error(pos,
2878 Errors.NameClashSameErasureNoHide(sym, sym.location(), s, s.location()));
2879 return;
2880 } else {
2881 checkPotentiallyAmbiguousOverloads(pos, site, sym, (MethodSymbol)s);
2882 }
2883 }
2884 }
2885 }
2886
2887 //where
2888 private class ClashFilter implements Predicate<Symbol> {
2889
2890 Type site;
2891
2892 ClashFilter(Type site) {
2893 this.site = site;
2894 }
2895
2896 boolean shouldSkip(Symbol s) {
2897 return (s.flags() & CLASH) != 0 &&
2898 s.owner == site.tsym;
2899 }
2900
2901 @Override
2902 public boolean test(Symbol s) {
2903 return s.kind == MTH &&
2904 (s.flags() & SYNTHETIC) == 0 &&
2905 !shouldSkip(s) &&
2906 s.isInheritedIn(site.tsym, types) &&
2907 !s.isConstructor();
2908 }
2909 }
2910
2911 void checkDefaultMethodClashes(DiagnosticPosition pos, Type site) {
2912 DefaultMethodClashFilter dcf = new DefaultMethodClashFilter(site);
2913 for (Symbol m : types.membersClosure(site, false).getSymbols(dcf)) {
2914 Assert.check(m.kind == MTH);
2915 List<MethodSymbol> prov = types.interfaceCandidates(site, (MethodSymbol)m);
2916 if (prov.size() > 1) {
2917 ListBuffer<Symbol> abstracts = new ListBuffer<>();
2918 ListBuffer<Symbol> defaults = new ListBuffer<>();
2919 for (MethodSymbol provSym : prov) {
2920 if ((provSym.flags() & DEFAULT) != 0) {
2921 defaults = defaults.append(provSym);
2922 } else if ((provSym.flags() & ABSTRACT) != 0) {
2923 abstracts = abstracts.append(provSym);
2924 }
2925 if (defaults.nonEmpty() && defaults.size() + abstracts.size() >= 2) {
2926 //strong semantics - issue an error if two sibling interfaces
2927 //have two override-equivalent defaults - or if one is abstract
2928 //and the other is default
2929 Fragment diagKey;
2930 Symbol s1 = defaults.first();
2931 Symbol s2;
2932 if (defaults.size() > 1) {
2933 s2 = defaults.toList().tail.head;
2934 diagKey = Fragments.IncompatibleUnrelatedDefaults(Kinds.kindName(site.tsym), site,
2935 m.name, types.memberType(site, m).getParameterTypes(),
2936 s1.location(), s2.location());
2937
2938 } else {
2939 s2 = abstracts.first();
2940 diagKey = Fragments.IncompatibleAbstractDefault(Kinds.kindName(site.tsym), site,
2941 m.name, types.memberType(site, m).getParameterTypes(),
2942 s1.location(), s2.location());
2943 }
2944 log.error(pos, Errors.TypesIncompatible(s1.location().type, s2.location().type, diagKey));
2945 break;
2946 }
2947 }
2948 }
2949 }
2950 }
2951
2952 //where
2953 private class DefaultMethodClashFilter implements Predicate<Symbol> {
2954
2955 Type site;
2956
2957 DefaultMethodClashFilter(Type site) {
2958 this.site = site;
2959 }
2960
2961 @Override
2962 public boolean test(Symbol s) {
2963 return s.kind == MTH &&
2964 (s.flags() & DEFAULT) != 0 &&
2965 s.isInheritedIn(site.tsym, types) &&
2966 !s.isConstructor();
2967 }
2968 }
2969
2970 /**
2971 * Report warnings for potentially ambiguous method declarations. Two declarations
2972 * are potentially ambiguous if they feature two unrelated functional interface
2973 * in same argument position (in which case, a call site passing an implicit
2974 * lambda would be ambiguous).
2975 */
2976 void checkPotentiallyAmbiguousOverloads(DiagnosticPosition pos, Type site,
2977 MethodSymbol msym1, MethodSymbol msym2) {
2978 if (msym1 != msym2 &&
2979 Feature.DEFAULT_METHODS.allowedInSource(source) &&
2980 lint.isEnabled(LintCategory.OVERLOADS) &&
2981 (msym1.flags() & POTENTIALLY_AMBIGUOUS) == 0 &&
2982 (msym2.flags() & POTENTIALLY_AMBIGUOUS) == 0) {
2983 Type mt1 = types.memberType(site, msym1);
2984 Type mt2 = types.memberType(site, msym2);
2985 //if both generic methods, adjust type variables
2986 if (mt1.hasTag(FORALL) && mt2.hasTag(FORALL) &&
2987 types.hasSameBounds((ForAll)mt1, (ForAll)mt2)) {
2988 mt2 = types.subst(mt2, ((ForAll)mt2).tvars, ((ForAll)mt1).tvars);
2989 }
2990 //expand varargs methods if needed
2991 int maxLength = Math.max(mt1.getParameterTypes().length(), mt2.getParameterTypes().length());
2992 List<Type> args1 = rs.adjustArgs(mt1.getParameterTypes(), msym1, maxLength, true);
2993 List<Type> args2 = rs.adjustArgs(mt2.getParameterTypes(), msym2, maxLength, true);
2994 //if arities don't match, exit
2995 if (args1.length() != args2.length()) return;
2996 boolean potentiallyAmbiguous = false;
2997 while (args1.nonEmpty() && args2.nonEmpty()) {
2998 Type s = args1.head;
2999 Type t = args2.head;
3000 if (!types.isSubtype(t, s) && !types.isSubtype(s, t)) {
3001 if (types.isFunctionalInterface(s) && types.isFunctionalInterface(t) &&
3002 types.findDescriptorType(s).getParameterTypes().length() > 0 &&
3003 types.findDescriptorType(s).getParameterTypes().length() ==
3004 types.findDescriptorType(t).getParameterTypes().length()) {
3005 potentiallyAmbiguous = true;
3006 } else {
3007 return;
3008 }
3009 }
3010 args1 = args1.tail;
3011 args2 = args2.tail;
3012 }
3013 if (potentiallyAmbiguous) {
3014 //we found two incompatible functional interfaces with same arity
3015 //this means a call site passing an implicit lambda would be ambiguous
3016 msym1.flags_field |= POTENTIALLY_AMBIGUOUS;
3017 msym2.flags_field |= POTENTIALLY_AMBIGUOUS;
3018 log.warning(LintCategory.OVERLOADS, pos,
3019 Warnings.PotentiallyAmbiguousOverload(msym1, msym1.location(),
3020 msym2, msym2.location()));
3021 return;
3022 }
3023 }
3024 }
3025
3026 void checkAccessFromSerializableElement(final JCTree tree, boolean isLambda) {
3027 if (warnOnAnyAccessToMembers ||
3028 (lint.isEnabled(LintCategory.SERIAL) &&
3029 !lint.isSuppressed(LintCategory.SERIAL) &&
3030 isLambda)) {
3031 Symbol sym = TreeInfo.symbol(tree);
3032 if (!sym.kind.matches(KindSelector.VAL_MTH)) {
3033 return;
3034 }
3035
3036 if (sym.kind == VAR) {
3037 if ((sym.flags() & PARAMETER) != 0 ||
3038 sym.isDirectlyOrIndirectlyLocal() ||
3039 sym.name == names._this ||
3040 sym.name == names._super) {
3041 return;
3042 }
3043 }
3044
3045 if (!types.isSubtype(sym.owner.type, syms.serializableType) &&
3046 isEffectivelyNonPublic(sym)) {
3047 if (isLambda) {
3048 if (belongsToRestrictedPackage(sym)) {
3049 log.warning(LintCategory.SERIAL, tree.pos(),
3050 Warnings.AccessToMemberFromSerializableLambda(sym));
3051 }
3052 } else {
3053 log.warning(tree.pos(),
3054 Warnings.AccessToMemberFromSerializableElement(sym));
3055 }
3056 }
3057 }
3058 }
3059
3060 private boolean isEffectivelyNonPublic(Symbol sym) {
3061 if (sym.packge() == syms.rootPackage) {
3062 return false;
3063 }
3064
3065 while (sym.kind != PCK) {
3066 if ((sym.flags() & PUBLIC) == 0) {
3067 return true;
3068 }
3069 sym = sym.owner;
3070 }
3071 return false;
3072 }
3073
3074 private boolean belongsToRestrictedPackage(Symbol sym) {
3075 String fullName = sym.packge().fullname.toString();
3076 return fullName.startsWith("java.") ||
3077 fullName.startsWith("javax.") ||
3078 fullName.startsWith("sun.") ||
3079 fullName.contains(".internal.");
3080 }
3081
3082 /** Check that class c does not implement directly or indirectly
3083 * the same parameterized interface with two different argument lists.
3084 * @param pos Position to be used for error reporting.
3085 * @param type The type whose interfaces are checked.
3086 */
3087 void checkClassBounds(DiagnosticPosition pos, Type type) {
3088 checkClassBounds(pos, new HashMap<TypeSymbol,Type>(), type);
3089 }
3090 //where
3091 /** Enter all interfaces of type `type' into the hash table `seensofar'
3092 * with their class symbol as key and their type as value. Make
3093 * sure no class is entered with two different types.
3094 */
3095 void checkClassBounds(DiagnosticPosition pos,
3096 Map<TypeSymbol,Type> seensofar,
3097 Type type) {
3098 if (type.isErroneous()) return;
3099 for (List<Type> l = types.interfaces(type); l.nonEmpty(); l = l.tail) {
3100 Type it = l.head;
3101 if (type.hasTag(CLASS) && !it.hasTag(CLASS)) continue; // JLS 8.1.5
3102
3103 Type oldit = seensofar.put(it.tsym, it);
3104 if (oldit != null) {
3105 List<Type> oldparams = oldit.allparams();
3106 List<Type> newparams = it.allparams();
3107 if (!types.containsTypeEquivalent(oldparams, newparams))
3108 log.error(pos,
3109 Errors.CantInheritDiffArg(it.tsym,
3110 Type.toString(oldparams),
3111 Type.toString(newparams)));
3112 }
3113 checkClassBounds(pos, seensofar, it);
3114 }
3115 Type st = types.supertype(type);
3116 if (type.hasTag(CLASS) && !st.hasTag(CLASS)) return; // JLS 8.1.4
3117 if (st != Type.noType) checkClassBounds(pos, seensofar, st);
3118 }
3119
3120 /** Enter interface into into set.
3121 * If it existed already, issue a "repeated interface" error.
3122 */
3123 void checkNotRepeated(DiagnosticPosition pos, Type it, Set<Type> its) {
3124 if (its.contains(it))
3125 log.error(pos, Errors.RepeatedInterface);
3126 else {
3127 its.add(it);
3128 }
3129 }
3130
3131 /* *************************************************************************
3132 * Check annotations
3133 **************************************************************************/
3134
3135 /**
3136 * Recursively validate annotations values
3137 */
3138 void validateAnnotationTree(JCTree tree) {
3139 class AnnotationValidator extends TreeScanner {
3140 @Override
3141 public void visitAnnotation(JCAnnotation tree) {
3142 if (!tree.type.isErroneous() && tree.type.tsym.isAnnotationType()) {
3143 super.visitAnnotation(tree);
3144 validateAnnotation(tree);
3145 }
3146 }
3147 }
3148 tree.accept(new AnnotationValidator());
3149 }
3150
3151 /**
3152 * {@literal
3153 * Annotation types are restricted to primitives, String, an
3154 * enum, an annotation, Class, Class<?>, Class<? extends
3155 * Anything>, arrays of the preceding.
3156 * }
3157 */
3158 void validateAnnotationType(JCTree restype) {
3159 // restype may be null if an error occurred, so don't bother validating it
3160 if (restype != null) {
3161 validateAnnotationType(restype.pos(), restype.type);
3162 }
3163 }
3164
3165 void validateAnnotationType(DiagnosticPosition pos, Type type) {
3166 if (type.isPrimitive()) return;
3167 if (types.isSameType(type, syms.stringType)) return;
3168 if ((type.tsym.flags() & Flags.ENUM) != 0) return;
3169 if ((type.tsym.flags() & Flags.ANNOTATION) != 0) return;
3170 if (types.cvarLowerBound(type).tsym == syms.classType.tsym) return;
3171 if (types.isArray(type) && !types.isArray(types.elemtype(type))) {
3172 validateAnnotationType(pos, types.elemtype(type));
3173 return;
3174 }
3175 log.error(pos, Errors.InvalidAnnotationMemberType);
3176 }
3177
3178 /**
3179 * "It is also a compile-time error if any method declared in an
3180 * annotation type has a signature that is override-equivalent to
3181 * that of any public or protected method declared in class Object
3182 * or in the interface annotation.Annotation."
3183 *
3184 * @jls 9.6 Annotation Types
3185 */
3186 void validateAnnotationMethod(DiagnosticPosition pos, MethodSymbol m) {
3187 for (Type sup = syms.annotationType; sup.hasTag(CLASS); sup = types.supertype(sup)) {
3188 Scope s = sup.tsym.members();
3189 for (Symbol sym : s.getSymbolsByName(m.name)) {
3190 if (sym.kind == MTH &&
3191 (sym.flags() & (PUBLIC | PROTECTED)) != 0 &&
3192 types.overrideEquivalent(m.type, sym.type))
3193 log.error(pos, Errors.IntfAnnotationMemberClash(sym, sup));
3194 }
3195 }
3196 }
3197
3198 /** Check the annotations of a symbol.
3199 */
3200 public void validateAnnotations(List<JCAnnotation> annotations, JCTree declarationTree, Symbol s) {
3201 for (JCAnnotation a : annotations)
3202 validateAnnotation(a, declarationTree, s);
3203 }
3204
3205 /** Check the type annotations.
3206 */
3207 public void validateTypeAnnotations(List<JCAnnotation> annotations, boolean isTypeParameter) {
3208 for (JCAnnotation a : annotations)
3209 validateTypeAnnotation(a, isTypeParameter);
3210 }
3211
3212 /** Check an annotation of a symbol.
3213 */
3214 private void validateAnnotation(JCAnnotation a, JCTree declarationTree, Symbol s) {
3215 validateAnnotationTree(a);
3216 boolean isRecordMember = ((s.flags_field & RECORD) != 0 || s.enclClass() != null && s.enclClass().isRecord());
3217
3218 boolean isRecordField = (s.flags_field & RECORD) != 0 &&
3219 declarationTree.hasTag(VARDEF) &&
3220 s.owner.kind == TYP;
3221
3222 if (isRecordField) {
3223 // first we need to check if the annotation is applicable to records
3224 Name[] targets = getTargetNames(a);
3225 boolean appliesToRecords = false;
3226 for (Name target : targets) {
3227 appliesToRecords =
3228 target == names.FIELD ||
3229 target == names.PARAMETER ||
3230 target == names.METHOD ||
3231 target == names.TYPE_USE ||
3232 target == names.RECORD_COMPONENT;
3233 if (appliesToRecords) {
3234 break;
3235 }
3236 }
3237 if (!appliesToRecords) {
3238 log.error(a.pos(), Errors.AnnotationTypeNotApplicable);
3239 } else {
3240 /* lets now find the annotations in the field that are targeted to record components and append them to
3241 * the corresponding record component
3242 */
3243 ClassSymbol recordClass = (ClassSymbol) s.owner;
3244 RecordComponent rc = recordClass.getRecordComponent((VarSymbol)s);
3245 SymbolMetadata metadata = rc.getMetadata();
3246 if (metadata == null || metadata.isEmpty()) {
3247 /* if not is empty then we have already been here, which is the case if multiple annotations are applied
3248 * to the record component declaration
3249 */
3250 rc.appendAttributes(s.getRawAttributes().stream().filter(anno ->
3251 Arrays.stream(getTargetNames(anno.type.tsym)).anyMatch(name -> name == names.RECORD_COMPONENT)
3252 ).collect(List.collector()));
3253 rc.setTypeAttributes(s.getRawTypeAttributes());
3254 // to get all the type annotations applied to the type
3255 rc.type = s.type;
3256 }
3257 }
3258 }
3259
3260 /* the section below is tricky. Annotations applied to record components are propagated to the corresponding
3261 * record member so if an annotation has target: FIELD, it is propagated to the corresponding FIELD, if it has
3262 * target METHOD, it is propagated to the accessor and so on. But at the moment when method members are generated
3263 * there is no enough information to propagate only the right annotations. So all the annotations are propagated
3264 * to all the possible locations.
3265 *
3266 * At this point we need to remove all the annotations that are not in place before going on with the annotation
3267 * party. On top of the above there is the issue that there is no AST representing record components, just symbols
3268 * so the corresponding field has been holding all the annotations and it's metadata has been modified as if it
3269 * was both a field and a record component.
3270 *
3271 * So there are two places where we need to trim annotations from: the metadata of the symbol and / or the modifiers
3272 * in the AST. Whatever is in the metadata will be written to the class file, whatever is in the modifiers could
3273 * be see by annotation processors.
3274 *
3275 * The metadata contains both type annotations and declaration annotations. At this point of the game we don't
3276 * need to care about type annotations, they are all in the right place. But we could need to remove declaration
3277 * annotations. So for declaration annotations if they are not applicable to the record member, excluding type
3278 * annotations which are already correct, then we will remove it. For the AST modifiers if the annotation is not
3279 * applicable either as type annotation and or declaration annotation, only in that case it will be removed.
3280 *
3281 * So it could be that annotation is removed as a declaration annotation but it is kept in the AST modifier for
3282 * further inspection by annotation processors.
3283 *
3284 * For example:
3285 *
3286 * import java.lang.annotation.*;
3287 *
3288 * @Target({ElementType.TYPE_USE, ElementType.RECORD_COMPONENT})
3289 * @Retention(RetentionPolicy.RUNTIME)
3290 * @interface Anno { }
3291 *
3292 * record R(@Anno String s) {}
3293 *
3294 * at this point we will have for the case of the generated field:
3295 * - @Anno in the modifier
3296 * - @Anno as a type annotation
3297 * - @Anno as a declaration annotation
3298 *
3299 * the last one should be removed because the annotation has not FIELD as target but it was applied as a
3300 * declaration annotation because the field was being treated both as a field and as a record component
3301 * as we have already copied the annotations to the record component, now the field doesn't need to hold
3302 * annotations that are not intended for it anymore. Still @Anno has to be kept in the AST's modifiers as it
3303 * is applicable as a type annotation to the type of the field.
3304 */
3305
3306 if (a.type.tsym.isAnnotationType()) {
3307 Optional<Set<Name>> applicableTargetsOp = getApplicableTargets(a, s);
3308 if (!applicableTargetsOp.isEmpty()) {
3309 Set<Name> applicableTargets = applicableTargetsOp.get();
3310 boolean notApplicableOrIsTypeUseOnly = applicableTargets.isEmpty() ||
3311 applicableTargets.size() == 1 && applicableTargets.contains(names.TYPE_USE);
3312 boolean isCompGeneratedRecordElement = isRecordMember && (s.flags_field & Flags.GENERATED_MEMBER) != 0;
3313 boolean isCompRecordElementWithNonApplicableDeclAnno = isCompGeneratedRecordElement && notApplicableOrIsTypeUseOnly;
3314
3315 if (applicableTargets.isEmpty() || isCompRecordElementWithNonApplicableDeclAnno) {
3316 if (isCompRecordElementWithNonApplicableDeclAnno) {
3317 /* so we have found an annotation that is not applicable to a record member that was generated by the
3318 * compiler. This was intentionally done at TypeEnter, now is the moment strip away the annotations
3319 * that are not applicable to the given record member
3320 */
3321 JCModifiers modifiers = TreeInfo.getModifiers(declarationTree);
3322 /* lets first remove the annotation from the modifier if it is not applicable, we have to check again as
3323 * it could be a type annotation
3324 */
3325 if (modifiers != null && applicableTargets.isEmpty()) {
3326 ListBuffer<JCAnnotation> newAnnotations = new ListBuffer<>();
3327 for (JCAnnotation anno : modifiers.annotations) {
3328 if (anno != a) {
3329 newAnnotations.add(anno);
3330 }
3331 }
3332 modifiers.annotations = newAnnotations.toList();
3333 }
3334 // now lets remove it from the symbol
3335 s.getMetadata().removeDeclarationMetadata(a.attribute);
3336 } else {
3337 log.error(a.pos(), Errors.AnnotationTypeNotApplicable);
3338 }
3339 }
3340 /* if we are seeing the @SafeVarargs annotation applied to a compiler generated accessor,
3341 * then this is an error as we know that no compiler generated accessor will be a varargs
3342 * method, better to fail asap
3343 */
3344 if (isCompGeneratedRecordElement && !isRecordField && a.type.tsym == syms.trustMeType.tsym && declarationTree.hasTag(METHODDEF)) {
3345 log.error(a.pos(), Errors.VarargsInvalidTrustmeAnno(syms.trustMeType.tsym, Fragments.VarargsTrustmeOnNonVarargsAccessor(s)));
3346 }
3347 }
3348 }
3349
3350 if (a.annotationType.type.tsym == syms.functionalInterfaceType.tsym) {
3351 if (s.kind != TYP) {
3352 log.error(a.pos(), Errors.BadFunctionalIntfAnno);
3353 } else if (!s.isInterface() || (s.flags() & ANNOTATION) != 0) {
3354 log.error(a.pos(), Errors.BadFunctionalIntfAnno1(Fragments.NotAFunctionalIntf(s)));
3355 }
3356 }
3357 }
3358
3359 public void validateTypeAnnotation(JCAnnotation a, boolean isTypeParameter) {
3360 Assert.checkNonNull(a.type);
3361 validateAnnotationTree(a);
3362
3363 if (a.hasTag(TYPE_ANNOTATION) &&
3364 !a.annotationType.type.isErroneous() &&
3365 !isTypeAnnotation(a, isTypeParameter)) {
3366 log.error(a.pos(), Errors.AnnotationTypeNotApplicableToType(a.type));
3367 }
3368 }
3369
3370 /**
3371 * Validate the proposed container 'repeatable' on the
3372 * annotation type symbol 's'. Report errors at position
3373 * 'pos'.
3374 *
3375 * @param s The (annotation)type declaration annotated with a @Repeatable
3376 * @param repeatable the @Repeatable on 's'
3377 * @param pos where to report errors
3378 */
3379 public void validateRepeatable(TypeSymbol s, Attribute.Compound repeatable, DiagnosticPosition pos) {
3380 Assert.check(types.isSameType(repeatable.type, syms.repeatableType));
3381
3382 Type t = null;
3383 List<Pair<MethodSymbol,Attribute>> l = repeatable.values;
3384 if (!l.isEmpty()) {
3385 Assert.check(l.head.fst.name == names.value);
3386 if (l.head.snd instanceof Attribute.Class) {
3387 t = ((Attribute.Class)l.head.snd).getValue();
3388 }
3389 }
3390
3391 if (t == null) {
3392 // errors should already have been reported during Annotate
3393 return;
3394 }
3395
3396 validateValue(t.tsym, s, pos);
3397 validateRetention(t.tsym, s, pos);
3398 validateDocumented(t.tsym, s, pos);
3399 validateInherited(t.tsym, s, pos);
3400 validateTarget(t.tsym, s, pos);
3401 validateDefault(t.tsym, pos);
3402 }
3403
3404 private void validateValue(TypeSymbol container, TypeSymbol contained, DiagnosticPosition pos) {
3405 Symbol sym = container.members().findFirst(names.value);
3406 if (sym != null && sym.kind == MTH) {
3407 MethodSymbol m = (MethodSymbol) sym;
3408 Type ret = m.getReturnType();
3409 if (!(ret.hasTag(ARRAY) && types.isSameType(((ArrayType)ret).elemtype, contained.type))) {
3410 log.error(pos,
3411 Errors.InvalidRepeatableAnnotationValueReturn(container,
3412 ret,
3413 types.makeArrayType(contained.type)));
3414 }
3415 } else {
3416 log.error(pos, Errors.InvalidRepeatableAnnotationNoValue(container));
3417 }
3418 }
3419
3420 private void validateRetention(TypeSymbol container, TypeSymbol contained, DiagnosticPosition pos) {
3421 Attribute.RetentionPolicy containerRetention = types.getRetention(container);
3422 Attribute.RetentionPolicy containedRetention = types.getRetention(contained);
3423
3424 boolean error = false;
3425 switch (containedRetention) {
3426 case RUNTIME:
3427 if (containerRetention != Attribute.RetentionPolicy.RUNTIME) {
3428 error = true;
3429 }
3430 break;
3431 case CLASS:
3432 if (containerRetention == Attribute.RetentionPolicy.SOURCE) {
3433 error = true;
3434 }
3435 }
3436 if (error ) {
3437 log.error(pos,
3438 Errors.InvalidRepeatableAnnotationRetention(container,
3439 containerRetention.name(),
3440 contained,
3441 containedRetention.name()));
3442 }
3443 }
3444
3445 private void validateDocumented(Symbol container, Symbol contained, DiagnosticPosition pos) {
3446 if (contained.attribute(syms.documentedType.tsym) != null) {
3447 if (container.attribute(syms.documentedType.tsym) == null) {
3448 log.error(pos, Errors.InvalidRepeatableAnnotationNotDocumented(container, contained));
3449 }
3450 }
3451 }
3452
3453 private void validateInherited(Symbol container, Symbol contained, DiagnosticPosition pos) {
3454 if (contained.attribute(syms.inheritedType.tsym) != null) {
3455 if (container.attribute(syms.inheritedType.tsym) == null) {
3456 log.error(pos, Errors.InvalidRepeatableAnnotationNotInherited(container, contained));
3457 }
3458 }
3459 }
3460
3461 private void validateTarget(TypeSymbol container, TypeSymbol contained, DiagnosticPosition pos) {
3462 // The set of targets the container is applicable to must be a subset
3463 // (with respect to annotation target semantics) of the set of targets
3464 // the contained is applicable to. The target sets may be implicit or
3465 // explicit.
3466
3467 Set<Name> containerTargets;
3468 Attribute.Array containerTarget = getAttributeTargetAttribute(container);
3469 if (containerTarget == null) {
3470 containerTargets = getDefaultTargetSet();
3471 } else {
3472 containerTargets = new HashSet<>();
3473 for (Attribute app : containerTarget.values) {
3474 if (!(app instanceof Attribute.Enum attributeEnum)) {
3475 continue; // recovery
3476 }
3477 containerTargets.add(attributeEnum.value.name);
3478 }
3479 }
3480
3481 Set<Name> containedTargets;
3482 Attribute.Array containedTarget = getAttributeTargetAttribute(contained);
3483 if (containedTarget == null) {
3484 containedTargets = getDefaultTargetSet();
3485 } else {
3486 containedTargets = new HashSet<>();
3487 for (Attribute app : containedTarget.values) {
3488 if (!(app instanceof Attribute.Enum attributeEnum)) {
3489 continue; // recovery
3490 }
3491 containedTargets.add(attributeEnum.value.name);
3492 }
3493 }
3494
3495 if (!isTargetSubsetOf(containerTargets, containedTargets)) {
3496 log.error(pos, Errors.InvalidRepeatableAnnotationIncompatibleTarget(container, contained));
3497 }
3498 }
3499
3500 /* get a set of names for the default target */
3501 private Set<Name> getDefaultTargetSet() {
3502 if (defaultTargets == null) {
3503 defaultTargets = Set.of(defaultTargetMetaInfo());
3504 }
3505
3506 return defaultTargets;
3507 }
3508 private Set<Name> defaultTargets;
3509
3510
3511 /** Checks that s is a subset of t, with respect to ElementType
3512 * semantics, specifically {ANNOTATION_TYPE} is a subset of {TYPE},
3513 * and {TYPE_USE} covers the set {ANNOTATION_TYPE, TYPE, TYPE_USE,
3514 * TYPE_PARAMETER}.
3515 */
3516 private boolean isTargetSubsetOf(Set<Name> s, Set<Name> t) {
3517 // Check that all elements in s are present in t
3518 for (Name n2 : s) {
3519 boolean currentElementOk = false;
3520 for (Name n1 : t) {
3521 if (n1 == n2) {
3522 currentElementOk = true;
3523 break;
3524 } else if (n1 == names.TYPE && n2 == names.ANNOTATION_TYPE) {
3525 currentElementOk = true;
3526 break;
3527 } else if (n1 == names.TYPE_USE &&
3528 (n2 == names.TYPE ||
3529 n2 == names.ANNOTATION_TYPE ||
3530 n2 == names.TYPE_PARAMETER)) {
3531 currentElementOk = true;
3532 break;
3533 }
3534 }
3535 if (!currentElementOk)
3536 return false;
3537 }
3538 return true;
3539 }
3540
3541 private void validateDefault(Symbol container, DiagnosticPosition pos) {
3542 // validate that all other elements of containing type has defaults
3543 Scope scope = container.members();
3544 for(Symbol elm : scope.getSymbols()) {
3545 if (elm.name != names.value &&
3546 elm.kind == MTH &&
3547 ((MethodSymbol)elm).defaultValue == null) {
3548 log.error(pos,
3549 Errors.InvalidRepeatableAnnotationElemNondefault(container, elm));
3550 }
3551 }
3552 }
3553
3554 /** Is s a method symbol that overrides a method in a superclass? */
3555 boolean isOverrider(Symbol s) {
3556 if (s.kind != MTH || s.isStatic())
3557 return false;
3558 MethodSymbol m = (MethodSymbol)s;
3559 TypeSymbol owner = (TypeSymbol)m.owner;
3560 for (Type sup : types.closure(owner.type)) {
3561 if (sup == owner.type)
3562 continue; // skip "this"
3563 Scope scope = sup.tsym.members();
3564 for (Symbol sym : scope.getSymbolsByName(m.name)) {
3565 if (!sym.isStatic() && m.overrides(sym, owner, types, true))
3566 return true;
3567 }
3568 }
3569 return false;
3570 }
3571
3572 /** Is the annotation applicable to types? */
3573 protected boolean isTypeAnnotation(JCAnnotation a, boolean isTypeParameter) {
3574 List<Attribute> targets = typeAnnotations.annotationTargets(a.annotationType.type.tsym);
3575 return (targets == null) ?
3576 false :
3577 targets.stream()
3578 .anyMatch(attr -> isTypeAnnotation(attr, isTypeParameter));
3579 }
3580 //where
3581 boolean isTypeAnnotation(Attribute a, boolean isTypeParameter) {
3582 Attribute.Enum e = (Attribute.Enum)a;
3583 return (e.value.name == names.TYPE_USE ||
3584 (isTypeParameter && e.value.name == names.TYPE_PARAMETER));
3585 }
3586
3587 /** Is the annotation applicable to the symbol? */
3588 Name[] getTargetNames(JCAnnotation a) {
3589 return getTargetNames(a.annotationType.type.tsym);
3590 }
3591
3592 public Name[] getTargetNames(TypeSymbol annoSym) {
3593 Attribute.Array arr = getAttributeTargetAttribute(annoSym);
3594 Name[] targets;
3595 if (arr == null) {
3596 targets = defaultTargetMetaInfo();
3597 } else {
3598 // TODO: can we optimize this?
3599 targets = new Name[arr.values.length];
3600 for (int i=0; i<arr.values.length; ++i) {
3601 Attribute app = arr.values[i];
3602 if (!(app instanceof Attribute.Enum attributeEnum)) {
3603 return new Name[0];
3604 }
3605 targets[i] = attributeEnum.value.name;
3606 }
3607 }
3608 return targets;
3609 }
3610
3611 boolean annotationApplicable(JCAnnotation a, Symbol s) {
3612 Optional<Set<Name>> targets = getApplicableTargets(a, s);
3613 /* the optional could be emtpy if the annotation is unknown in that case
3614 * we return that it is applicable and if it is erroneous that should imply
3615 * an error at the declaration site
3616 */
3617 return targets.isEmpty() || targets.isPresent() && !targets.get().isEmpty();
3618 }
3619
3620 Optional<Set<Name>> getApplicableTargets(JCAnnotation a, Symbol s) {
3621 Attribute.Array arr = getAttributeTargetAttribute(a.annotationType.type.tsym);
3622 Name[] targets;
3623 Set<Name> applicableTargets = new HashSet<>();
3624
3625 if (arr == null) {
3626 targets = defaultTargetMetaInfo();
3627 } else {
3628 // TODO: can we optimize this?
3629 targets = new Name[arr.values.length];
3630 for (int i=0; i<arr.values.length; ++i) {
3631 Attribute app = arr.values[i];
3632 if (!(app instanceof Attribute.Enum attributeEnum)) {
3633 // recovery
3634 return Optional.empty();
3635 }
3636 targets[i] = attributeEnum.value.name;
3637 }
3638 }
3639 for (Name target : targets) {
3640 if (target == names.TYPE) {
3641 if (s.kind == TYP)
3642 applicableTargets.add(names.TYPE);
3643 } else if (target == names.FIELD) {
3644 if (s.kind == VAR && s.owner.kind != MTH)
3645 applicableTargets.add(names.FIELD);
3646 } else if (target == names.RECORD_COMPONENT) {
3647 if (s.getKind() == ElementKind.RECORD_COMPONENT) {
3648 applicableTargets.add(names.RECORD_COMPONENT);
3649 }
3650 } else if (target == names.METHOD) {
3651 if (s.kind == MTH && !s.isConstructor())
3652 applicableTargets.add(names.METHOD);
3653 } else if (target == names.PARAMETER) {
3654 if (s.kind == VAR &&
3655 (s.owner.kind == MTH && (s.flags() & PARAMETER) != 0)) {
3656 applicableTargets.add(names.PARAMETER);
3657 }
3658 } else if (target == names.CONSTRUCTOR) {
3659 if (s.kind == MTH && s.isConstructor())
3660 applicableTargets.add(names.CONSTRUCTOR);
3661 } else if (target == names.LOCAL_VARIABLE) {
3662 if (s.kind == VAR && s.owner.kind == MTH &&
3663 (s.flags() & PARAMETER) == 0) {
3664 applicableTargets.add(names.LOCAL_VARIABLE);
3665 }
3666 } else if (target == names.ANNOTATION_TYPE) {
3667 if (s.kind == TYP && (s.flags() & ANNOTATION) != 0) {
3668 applicableTargets.add(names.ANNOTATION_TYPE);
3669 }
3670 } else if (target == names.PACKAGE) {
3671 if (s.kind == PCK)
3672 applicableTargets.add(names.PACKAGE);
3673 } else if (target == names.TYPE_USE) {
3674 if (s.kind == VAR && s.owner.kind == MTH && s.type.hasTag(NONE)) {
3675 //cannot type annotate implicitly typed locals
3676 continue;
3677 } else if (s.kind == TYP || s.kind == VAR ||
3678 (s.kind == MTH && !s.isConstructor() &&
3679 !s.type.getReturnType().hasTag(VOID)) ||
3680 (s.kind == MTH && s.isConstructor())) {
3681 applicableTargets.add(names.TYPE_USE);
3682 }
3683 } else if (target == names.TYPE_PARAMETER) {
3684 if (s.kind == TYP && s.type.hasTag(TYPEVAR))
3685 applicableTargets.add(names.TYPE_PARAMETER);
3686 } else if (target == names.MODULE) {
3687 if (s.kind == MDL)
3688 applicableTargets.add(names.MODULE);
3689 } else
3690 return Optional.empty(); // Unknown ElementType. This should be an error at declaration site,
3691 // assume applicable.
3692 }
3693 return Optional.of(applicableTargets);
3694 }
3695
3696 Attribute.Array getAttributeTargetAttribute(TypeSymbol s) {
3697 Attribute.Compound atTarget = s.getAnnotationTypeMetadata().getTarget();
3698 if (atTarget == null) return null; // ok, is applicable
3699 Attribute atValue = atTarget.member(names.value);
3700 return (atValue instanceof Attribute.Array attributeArray) ? attributeArray : null;
3701 }
3702
3703 private Name[] dfltTargetMeta;
3704 private Name[] defaultTargetMetaInfo() {
3705 if (dfltTargetMeta == null) {
3706 ArrayList<Name> defaultTargets = new ArrayList<>();
3707 defaultTargets.add(names.PACKAGE);
3708 defaultTargets.add(names.TYPE);
3709 defaultTargets.add(names.FIELD);
3710 defaultTargets.add(names.METHOD);
3711 defaultTargets.add(names.CONSTRUCTOR);
3712 defaultTargets.add(names.ANNOTATION_TYPE);
3713 defaultTargets.add(names.LOCAL_VARIABLE);
3714 defaultTargets.add(names.PARAMETER);
3715 if (allowRecords) {
3716 defaultTargets.add(names.RECORD_COMPONENT);
3717 }
3718 if (allowModules) {
3719 defaultTargets.add(names.MODULE);
3720 }
3721 dfltTargetMeta = defaultTargets.toArray(new Name[0]);
3722 }
3723 return dfltTargetMeta;
3724 }
3725
3726 /** Check an annotation value.
3727 *
3728 * @param a The annotation tree to check
3729 * @return true if this annotation tree is valid, otherwise false
3730 */
3731 public boolean validateAnnotationDeferErrors(JCAnnotation a) {
3732 boolean res = false;
3733 final Log.DiagnosticHandler diagHandler = new Log.DiscardDiagnosticHandler(log);
3734 try {
3735 res = validateAnnotation(a);
3736 } finally {
3737 log.popDiagnosticHandler(diagHandler);
3738 }
3739 return res;
3740 }
3741
3742 private boolean validateAnnotation(JCAnnotation a) {
3743 boolean isValid = true;
3744 AnnotationTypeMetadata metadata = a.annotationType.type.tsym.getAnnotationTypeMetadata();
3745
3746 // collect an inventory of the annotation elements
3747 Set<MethodSymbol> elements = metadata.getAnnotationElements();
3748
3749 // remove the ones that are assigned values
3750 for (JCTree arg : a.args) {
3751 if (!arg.hasTag(ASSIGN)) continue; // recovery
3752 JCAssign assign = (JCAssign)arg;
3753 Symbol m = TreeInfo.symbol(assign.lhs);
3754 if (m == null || m.type.isErroneous()) continue;
3755 if (!elements.remove(m)) {
3756 isValid = false;
3757 log.error(assign.lhs.pos(),
3758 Errors.DuplicateAnnotationMemberValue(m.name, a.type));
3759 }
3760 }
3761
3762 // all the remaining ones better have default values
3763 List<Name> missingDefaults = List.nil();
3764 Set<MethodSymbol> membersWithDefault = metadata.getAnnotationElementsWithDefault();
3765 for (MethodSymbol m : elements) {
3766 if (m.type.isErroneous())
3767 continue;
3768
3769 if (!membersWithDefault.contains(m))
3770 missingDefaults = missingDefaults.append(m.name);
3771 }
3772 missingDefaults = missingDefaults.reverse();
3773 if (missingDefaults.nonEmpty()) {
3774 isValid = false;
3775 Error errorKey = (missingDefaults.size() > 1)
3776 ? Errors.AnnotationMissingDefaultValue1(a.type, missingDefaults)
3777 : Errors.AnnotationMissingDefaultValue(a.type, missingDefaults);
3778 log.error(a.pos(), errorKey);
3779 }
3780
3781 return isValid && validateTargetAnnotationValue(a);
3782 }
3783
3784 /* Validate the special java.lang.annotation.Target annotation */
3785 boolean validateTargetAnnotationValue(JCAnnotation a) {
3786 // special case: java.lang.annotation.Target must not have
3787 // repeated values in its value member
3788 if (a.annotationType.type.tsym != syms.annotationTargetType.tsym ||
3789 a.args.tail == null)
3790 return true;
3791
3792 boolean isValid = true;
3793 if (!a.args.head.hasTag(ASSIGN)) return false; // error recovery
3794 JCAssign assign = (JCAssign) a.args.head;
3795 Symbol m = TreeInfo.symbol(assign.lhs);
3796 if (m.name != names.value) return false;
3797 JCTree rhs = assign.rhs;
3798 if (!rhs.hasTag(NEWARRAY)) return false;
3799 JCNewArray na = (JCNewArray) rhs;
3800 Set<Symbol> targets = new HashSet<>();
3801 for (JCTree elem : na.elems) {
3802 if (!targets.add(TreeInfo.symbol(elem))) {
3803 isValid = false;
3804 log.error(elem.pos(), Errors.RepeatedAnnotationTarget);
3805 }
3806 }
3807 return isValid;
3808 }
3809
3810 void checkDeprecatedAnnotation(DiagnosticPosition pos, Symbol s) {
3811 if (lint.isEnabled(LintCategory.DEP_ANN) && s.isDeprecatableViaAnnotation() &&
3812 (s.flags() & DEPRECATED) != 0 &&
3813 !syms.deprecatedType.isErroneous() &&
3814 s.attribute(syms.deprecatedType.tsym) == null) {
3815 log.warning(LintCategory.DEP_ANN,
3816 pos, Warnings.MissingDeprecatedAnnotation);
3817 }
3818 // Note: @Deprecated has no effect on local variables, parameters and package decls.
3819 if (lint.isEnabled(LintCategory.DEPRECATION) && !s.isDeprecatableViaAnnotation()) {
3820 if (!syms.deprecatedType.isErroneous() && s.attribute(syms.deprecatedType.tsym) != null) {
3821 log.warning(LintCategory.DEPRECATION, pos,
3822 Warnings.DeprecatedAnnotationHasNoEffect(Kinds.kindName(s)));
3823 }
3824 }
3825 }
3826
3827 void checkDeprecated(final DiagnosticPosition pos, final Symbol other, final Symbol s) {
3828 checkDeprecated(() -> pos, other, s);
3829 }
3830
3831 void checkDeprecated(Supplier<DiagnosticPosition> pos, final Symbol other, final Symbol s) {
3832 if ( (s.isDeprecatedForRemoval()
3833 || s.isDeprecated() && !other.isDeprecated())
3834 && (s.outermostClass() != other.outermostClass() || s.outermostClass() == null)
3835 && s.kind != Kind.PCK) {
3836 deferredLintHandler.report(() -> warnDeprecated(pos.get(), s));
3837 }
3838 }
3839
3840 void checkSunAPI(final DiagnosticPosition pos, final Symbol s) {
3841 if ((s.flags() & PROPRIETARY) != 0) {
3842 deferredLintHandler.report(() -> {
3843 log.mandatoryWarning(pos, Warnings.SunProprietary(s));
3844 });
3845 }
3846 }
3847
3848 void checkProfile(final DiagnosticPosition pos, final Symbol s) {
3849 if (profile != Profile.DEFAULT && (s.flags() & NOT_IN_PROFILE) != 0) {
3850 log.error(pos, Errors.NotInProfile(s, profile));
3851 }
3852 }
3853
3854 void checkPreview(DiagnosticPosition pos, Symbol other, Symbol s) {
3855 if ((s.flags() & PREVIEW_API) != 0 && s.packge().modle != other.packge().modle) {
3856 if ((s.flags() & PREVIEW_REFLECTIVE) == 0) {
3857 if (!preview.isEnabled()) {
3858 log.error(pos, Errors.IsPreview(s));
3859 } else {
3860 preview.markUsesPreview(pos);
3861 deferredLintHandler.report(() -> warnPreviewAPI(pos, Warnings.IsPreview(s)));
3862 }
3863 } else {
3864 deferredLintHandler.report(() -> warnPreviewAPI(pos, Warnings.IsPreviewReflective(s)));
3865 }
3866 }
3867 if (preview.declaredUsingPreviewFeature(s)) {
3868 if (preview.isEnabled()) {
3869 //for preview disabled do presumably so not need to do anything?
3870 //If "s" is compiled from source, then there was an error for it already;
3871 //if "s" is from classfile, there already was an error for the classfile.
3872 preview.markUsesPreview(pos);
3873 deferredLintHandler.report(() -> warnDeclaredUsingPreview(pos, s));
3874 }
3875 }
3876 }
3877
3878 /* *************************************************************************
3879 * Check for recursive annotation elements.
3880 **************************************************************************/
3881
3882 /** Check for cycles in the graph of annotation elements.
3883 */
3884 void checkNonCyclicElements(JCClassDecl tree) {
3885 if ((tree.sym.flags_field & ANNOTATION) == 0) return;
3886 Assert.check((tree.sym.flags_field & LOCKED) == 0);
3887 try {
3888 tree.sym.flags_field |= LOCKED;
3889 for (JCTree def : tree.defs) {
3890 if (!def.hasTag(METHODDEF)) continue;
3891 JCMethodDecl meth = (JCMethodDecl)def;
3892 checkAnnotationResType(meth.pos(), meth.restype.type);
3893 }
3894 } finally {
3895 tree.sym.flags_field &= ~LOCKED;
3896 tree.sym.flags_field |= ACYCLIC_ANN;
3897 }
3898 }
3899
3900 void checkNonCyclicElementsInternal(DiagnosticPosition pos, TypeSymbol tsym) {
3901 if ((tsym.flags_field & ACYCLIC_ANN) != 0)
3902 return;
3903 if ((tsym.flags_field & LOCKED) != 0) {
3904 log.error(pos, Errors.CyclicAnnotationElement(tsym));
3905 return;
3906 }
3907 try {
3908 tsym.flags_field |= LOCKED;
3909 for (Symbol s : tsym.members().getSymbols(NON_RECURSIVE)) {
3910 if (s.kind != MTH)
3911 continue;
3912 checkAnnotationResType(pos, ((MethodSymbol)s).type.getReturnType());
3913 }
3914 } finally {
3915 tsym.flags_field &= ~LOCKED;
3916 tsym.flags_field |= ACYCLIC_ANN;
3917 }
3918 }
3919
3920 void checkAnnotationResType(DiagnosticPosition pos, Type type) {
3921 switch (type.getTag()) {
3922 case CLASS:
3923 if ((type.tsym.flags() & ANNOTATION) != 0)
3924 checkNonCyclicElementsInternal(pos, type.tsym);
3925 break;
3926 case ARRAY:
3927 checkAnnotationResType(pos, types.elemtype(type));
3928 break;
3929 default:
3930 break; // int etc
3931 }
3932 }
3933
3934 /* *************************************************************************
3935 * Check for cycles in the constructor call graph.
3936 **************************************************************************/
3937
3938 /** Check for cycles in the graph of constructors calling other
3939 * constructors.
3940 */
3941 void checkCyclicConstructors(JCClassDecl tree) {
3942 Map<Symbol,Symbol> callMap = new HashMap<>();
3943
3944 // enter each constructor this-call into the map
3945 for (List<JCTree> l = tree.defs; l.nonEmpty(); l = l.tail) {
3946 JCMethodInvocation app = TreeInfo.firstConstructorCall(l.head);
3947 if (app == null) continue;
3948 JCMethodDecl meth = (JCMethodDecl) l.head;
3949 if (TreeInfo.name(app.meth) == names._this) {
3950 callMap.put(meth.sym, TreeInfo.symbol(app.meth));
3951 } else {
3952 meth.sym.flags_field |= ACYCLIC;
3953 }
3954 }
3955
3956 // Check for cycles in the map
3957 Symbol[] ctors = new Symbol[0];
3958 ctors = callMap.keySet().toArray(ctors);
3959 for (Symbol caller : ctors) {
3960 checkCyclicConstructor(tree, caller, callMap);
3961 }
3962 }
3963
3964 /** Look in the map to see if the given constructor is part of a
3965 * call cycle.
3966 */
3967 private void checkCyclicConstructor(JCClassDecl tree, Symbol ctor,
3968 Map<Symbol,Symbol> callMap) {
3969 if (ctor != null && (ctor.flags_field & ACYCLIC) == 0) {
3970 if ((ctor.flags_field & LOCKED) != 0) {
3971 log.error(TreeInfo.diagnosticPositionFor(ctor, tree),
3972 Errors.RecursiveCtorInvocation);
3973 } else {
3974 ctor.flags_field |= LOCKED;
3975 checkCyclicConstructor(tree, callMap.remove(ctor), callMap);
3976 ctor.flags_field &= ~LOCKED;
3977 }
3978 ctor.flags_field |= ACYCLIC;
3979 }
3980 }
3981
3982 /* *************************************************************************
3983 * Miscellaneous
3984 **************************************************************************/
3985
3986 /**
3987 * Check for division by integer constant zero
3988 * @param pos Position for error reporting.
3989 * @param operator The operator for the expression
3990 * @param operand The right hand operand for the expression
3991 */
3992 void checkDivZero(final DiagnosticPosition pos, Symbol operator, Type operand) {
3993 if (operand.constValue() != null
3994 && operand.getTag().isSubRangeOf(LONG)
3995 && ((Number) (operand.constValue())).longValue() == 0) {
3996 int opc = ((OperatorSymbol)operator).opcode;
3997 if (opc == ByteCodes.idiv || opc == ByteCodes.imod
3998 || opc == ByteCodes.ldiv || opc == ByteCodes.lmod) {
3999 deferredLintHandler.report(() -> warnDivZero(pos));
4000 }
4001 }
4002 }
4003
4004 /**
4005 * Check for empty statements after if
4006 */
4007 void checkEmptyIf(JCIf tree) {
4008 if (tree.thenpart.hasTag(SKIP) && tree.elsepart == null &&
4009 lint.isEnabled(LintCategory.EMPTY))
4010 log.warning(LintCategory.EMPTY, tree.thenpart.pos(), Warnings.EmptyIf);
4011 }
4012
4013 /** Check that symbol is unique in given scope.
4014 * @param pos Position for error reporting.
4015 * @param sym The symbol.
4016 * @param s The scope.
4017 */
4018 boolean checkUnique(DiagnosticPosition pos, Symbol sym, Scope s) {
4019 if (sym.type.isErroneous())
4020 return true;
4021 if (sym.owner.name == names.any) return false;
4022 for (Symbol byName : s.getSymbolsByName(sym.name, NON_RECURSIVE)) {
4023 if (sym != byName &&
4024 (byName.flags() & CLASH) == 0 &&
4025 sym.kind == byName.kind &&
4026 sym.name != names.error &&
4027 (sym.kind != MTH ||
4028 types.hasSameArgs(sym.type, byName.type) ||
4029 types.hasSameArgs(types.erasure(sym.type), types.erasure(byName.type)))) {
4030 if ((sym.flags() & VARARGS) != (byName.flags() & VARARGS)) {
4031 sym.flags_field |= CLASH;
4032 varargsDuplicateError(pos, sym, byName);
4033 return true;
4034 } else if (sym.kind == MTH && !types.hasSameArgs(sym.type, byName.type, false)) {
4035 duplicateErasureError(pos, sym, byName);
4036 sym.flags_field |= CLASH;
4037 return true;
4038 } else if ((sym.flags() & MATCH_BINDING) != 0 &&
4039 (byName.flags() & MATCH_BINDING) != 0 &&
4040 (byName.flags() & MATCH_BINDING_TO_OUTER) == 0) {
4041 if (!sym.type.isErroneous()) {
4042 log.error(pos, Errors.MatchBindingExists);
4043 sym.flags_field |= CLASH;
4044 }
4045 return false;
4046 } else {
4047 duplicateError(pos, byName);
4048 return false;
4049 }
4050 }
4051 }
4052 return true;
4053 }
4054
4055 /** Report duplicate declaration error.
4056 */
4057 void duplicateErasureError(DiagnosticPosition pos, Symbol sym1, Symbol sym2) {
4058 if (!sym1.type.isErroneous() && !sym2.type.isErroneous()) {
4059 log.error(pos, Errors.NameClashSameErasure(sym1, sym2));
4060 }
4061 }
4062
4063 /**Check that types imported through the ordinary imports don't clash with types imported
4064 * by other (static or ordinary) imports. Note that two static imports may import two clashing
4065 * types without an error on the imports.
4066 * @param toplevel The toplevel tree for which the test should be performed.
4067 */
4068 void checkImportsUnique(JCCompilationUnit toplevel) {
4069 WriteableScope ordinallyImportedSoFar = WriteableScope.create(toplevel.packge);
4070 WriteableScope staticallyImportedSoFar = WriteableScope.create(toplevel.packge);
4071 WriteableScope topLevelScope = toplevel.toplevelScope;
4072
4073 for (JCTree def : toplevel.defs) {
4074 if (!def.hasTag(IMPORT))
4075 continue;
4076
4077 JCImport imp = (JCImport) def;
4078
4079 if (imp.importScope == null)
4080 continue;
4081
4082 for (Symbol sym : imp.importScope.getSymbols(sym -> sym.kind == TYP)) {
4083 if (imp.isStatic()) {
4084 checkUniqueImport(imp.pos(), ordinallyImportedSoFar, staticallyImportedSoFar, topLevelScope, sym, true);
4085 staticallyImportedSoFar.enter(sym);
4086 } else {
4087 checkUniqueImport(imp.pos(), ordinallyImportedSoFar, staticallyImportedSoFar, topLevelScope, sym, false);
4088 ordinallyImportedSoFar.enter(sym);
4089 }
4090 }
4091
4092 imp.importScope = null;
4093 }
4094 }
4095
4096 /** Check that single-type import is not already imported or top-level defined,
4097 * but make an exception for two single-type imports which denote the same type.
4098 * @param pos Position for error reporting.
4099 * @param ordinallyImportedSoFar A Scope containing types imported so far through
4100 * ordinary imports.
4101 * @param staticallyImportedSoFar A Scope containing types imported so far through
4102 * static imports.
4103 * @param topLevelScope The current file's top-level Scope
4104 * @param sym The symbol.
4105 * @param staticImport Whether or not this was a static import
4106 */
4107 private boolean checkUniqueImport(DiagnosticPosition pos, Scope ordinallyImportedSoFar,
4108 Scope staticallyImportedSoFar, Scope topLevelScope,
4109 Symbol sym, boolean staticImport) {
4110 Predicate<Symbol> duplicates = candidate -> candidate != sym && !candidate.type.isErroneous();
4111 Symbol ordinaryClashing = ordinallyImportedSoFar.findFirst(sym.name, duplicates);
4112 Symbol staticClashing = null;
4113 if (ordinaryClashing == null && !staticImport) {
4114 staticClashing = staticallyImportedSoFar.findFirst(sym.name, duplicates);
4115 }
4116 if (ordinaryClashing != null || staticClashing != null) {
4117 if (ordinaryClashing != null)
4118 log.error(pos, Errors.AlreadyDefinedSingleImport(ordinaryClashing));
4119 else
4120 log.error(pos, Errors.AlreadyDefinedStaticSingleImport(staticClashing));
4121 return false;
4122 }
4123 Symbol clashing = topLevelScope.findFirst(sym.name, duplicates);
4124 if (clashing != null) {
4125 log.error(pos, Errors.AlreadyDefinedThisUnit(clashing));
4126 return false;
4127 }
4128 return true;
4129 }
4130
4131 /** Check that a qualified name is in canonical form (for import decls).
4132 */
4133 public void checkCanonical(JCTree tree) {
4134 if (!isCanonical(tree))
4135 log.error(tree.pos(),
4136 Errors.ImportRequiresCanonical(TreeInfo.symbol(tree)));
4137 }
4138 // where
4139 private boolean isCanonical(JCTree tree) {
4140 while (tree.hasTag(SELECT)) {
4141 JCFieldAccess s = (JCFieldAccess) tree;
4142 if (s.sym.owner.getQualifiedName() != TreeInfo.symbol(s.selected).getQualifiedName())
4143 return false;
4144 tree = s.selected;
4145 }
4146 return true;
4147 }
4148
4149 /** Check that an auxiliary class is not accessed from any other file than its own.
4150 */
4151 void checkForBadAuxiliaryClassAccess(DiagnosticPosition pos, Env<AttrContext> env, ClassSymbol c) {
4152 if (lint.isEnabled(Lint.LintCategory.AUXILIARYCLASS) &&
4153 (c.flags() & AUXILIARY) != 0 &&
4154 rs.isAccessible(env, c) &&
4155 !fileManager.isSameFile(c.sourcefile, env.toplevel.sourcefile))
4156 {
4157 log.warning(pos,
4158 Warnings.AuxiliaryClassAccessedFromOutsideOfItsSourceFile(c, c.sourcefile));
4159 }
4160 }
4161
4162 /**
4163 * Check for a default constructor in an exported package.
4164 */
4165 void checkDefaultConstructor(ClassSymbol c, DiagnosticPosition pos) {
4166 if (lint.isEnabled(LintCategory.MISSING_EXPLICIT_CTOR) &&
4167 ((c.flags() & (ENUM | RECORD)) == 0) &&
4168 !c.isAnonymous() &&
4169 ((c.flags() & (PUBLIC | PROTECTED)) != 0) &&
4170 Feature.MODULES.allowedInSource(source)) {
4171 NestingKind nestingKind = c.getNestingKind();
4172 switch (nestingKind) {
4173 case ANONYMOUS,
4174 LOCAL -> {return;}
4175 case TOP_LEVEL -> {;} // No additional checks needed
4176 case MEMBER -> {
4177 // For nested member classes, all the enclosing
4178 // classes must be public or protected.
4179 Symbol owner = c.owner;
4180 while (owner != null && owner.kind == TYP) {
4181 if ((owner.flags() & (PUBLIC | PROTECTED)) == 0)
4182 return;
4183 owner = owner.owner;
4184 }
4185 }
4186 }
4187
4188 // Only check classes in named packages exported by its module
4189 PackageSymbol pkg = c.packge();
4190 if (!pkg.isUnnamed()) {
4191 ModuleSymbol modle = pkg.modle;
4192 for (ExportsDirective exportDir : modle.exports) {
4193 // Report warning only if the containing
4194 // package is unconditionally exported
4195 if (exportDir.packge.equals(pkg)) {
4196 if (exportDir.modules == null || exportDir.modules.isEmpty()) {
4197 // Warning may be suppressed by
4198 // annotations; check again for being
4199 // enabled in the deferred context.
4200 deferredLintHandler.report(() -> {
4201 if (lint.isEnabled(LintCategory.MISSING_EXPLICIT_CTOR))
4202 log.warning(LintCategory.MISSING_EXPLICIT_CTOR,
4203 pos, Warnings.MissingExplicitCtor(c, pkg, modle));
4204 });
4205 } else {
4206 return;
4207 }
4208 }
4209 }
4210 }
4211 }
4212 return;
4213 }
4214
4215 private class ConversionWarner extends Warner {
4216 final String uncheckedKey;
4217 final Type found;
4218 final Type expected;
4219 public ConversionWarner(DiagnosticPosition pos, String uncheckedKey, Type found, Type expected) {
4220 super(pos);
4221 this.uncheckedKey = uncheckedKey;
4222 this.found = found;
4223 this.expected = expected;
4224 }
4225
4226 @Override
4227 public void warn(LintCategory lint) {
4228 boolean warned = this.warned;
4229 super.warn(lint);
4230 if (warned) return; // suppress redundant diagnostics
4231 switch (lint) {
4232 case UNCHECKED:
4233 Check.this.warnUnchecked(pos(), Warnings.ProbFoundReq(diags.fragment(uncheckedKey), found, expected));
4234 break;
4235 case VARARGS:
4236 if (method != null &&
4237 method.attribute(syms.trustMeType.tsym) != null &&
4238 isTrustMeAllowedOnMethod(method) &&
4239 !types.isReifiable(method.type.getParameterTypes().last())) {
4240 Check.this.warnUnsafeVararg(pos(), Warnings.VarargsUnsafeUseVarargsParam(method.params.last()));
4241 }
4242 break;
4243 default:
4244 throw new AssertionError("Unexpected lint: " + lint);
4245 }
4246 }
4247 }
4248
4249 public Warner castWarner(DiagnosticPosition pos, Type found, Type expected) {
4250 return new ConversionWarner(pos, "unchecked.cast.to.type", found, expected);
4251 }
4252
4253 public Warner convertWarner(DiagnosticPosition pos, Type found, Type expected) {
4254 return new ConversionWarner(pos, "unchecked.assign", found, expected);
4255 }
4256
4257 public void checkFunctionalInterface(JCClassDecl tree, ClassSymbol cs) {
4258 Compound functionalType = cs.attribute(syms.functionalInterfaceType.tsym);
4259
4260 if (functionalType != null) {
4261 try {
4262 types.findDescriptorSymbol((TypeSymbol)cs);
4263 } catch (Types.FunctionDescriptorLookupError ex) {
4264 DiagnosticPosition pos = tree.pos();
4265 for (JCAnnotation a : tree.getModifiers().annotations) {
4266 if (a.annotationType.type.tsym == syms.functionalInterfaceType.tsym) {
4267 pos = a.pos();
4268 break;
4269 }
4270 }
4271 log.error(pos, Errors.BadFunctionalIntfAnno1(ex.getDiagnostic()));
4272 }
4273 }
4274 }
4275
4276 public void checkImportsResolvable(final JCCompilationUnit toplevel) {
4277 for (final JCImport imp : toplevel.getImports()) {
4278 if (!imp.staticImport || !imp.qualid.hasTag(SELECT))
4279 continue;
4280 final JCFieldAccess select = (JCFieldAccess) imp.qualid;
4281 final Symbol origin;
4282 if (select.name == names.asterisk || (origin = TreeInfo.symbol(select.selected)) == null || origin.kind != TYP)
4283 continue;
4284
4285 TypeSymbol site = (TypeSymbol) TreeInfo.symbol(select.selected);
4286 if (!checkTypeContainsImportableElement(site, site, toplevel.packge, select.name, new HashSet<Symbol>())) {
4287 log.error(imp.pos(),
4288 Errors.CantResolveLocation(KindName.STATIC,
4289 select.name,
4290 null,
4291 null,
4292 Fragments.Location(kindName(site),
4293 site,
4294 null)));
4295 }
4296 }
4297 }
4298
4299 // Check that packages imported are in scope (JLS 7.4.3, 6.3, 6.5.3.1, 6.5.3.2)
4300 public void checkImportedPackagesObservable(final JCCompilationUnit toplevel) {
4301 OUTER: for (JCImport imp : toplevel.getImports()) {
4302 if (!imp.staticImport && TreeInfo.name(imp.qualid) == names.asterisk) {
4303 TypeSymbol tsym = ((JCFieldAccess)imp.qualid).selected.type.tsym;
4304 if (tsym.kind == PCK && tsym.members().isEmpty() &&
4305 !(Feature.IMPORT_ON_DEMAND_OBSERVABLE_PACKAGES.allowedInSource(source) && tsym.exists())) {
4306 log.error(DiagnosticFlag.RESOLVE_ERROR, imp.pos, Errors.DoesntExist(tsym));
4307 }
4308 }
4309 }
4310 }
4311
4312 private boolean checkTypeContainsImportableElement(TypeSymbol tsym, TypeSymbol origin, PackageSymbol packge, Name name, Set<Symbol> processed) {
4313 if (tsym == null || !processed.add(tsym))
4314 return false;
4315
4316 // also search through inherited names
4317 if (checkTypeContainsImportableElement(types.supertype(tsym.type).tsym, origin, packge, name, processed))
4318 return true;
4319
4320 for (Type t : types.interfaces(tsym.type))
4321 if (checkTypeContainsImportableElement(t.tsym, origin, packge, name, processed))
4322 return true;
4323
4324 for (Symbol sym : tsym.members().getSymbolsByName(name)) {
4325 if (sym.isStatic() &&
4326 importAccessible(sym, packge) &&
4327 sym.isMemberOf(origin, types)) {
4328 return true;
4329 }
4330 }
4331
4332 return false;
4333 }
4334
4335 // is the sym accessible everywhere in packge?
4336 public boolean importAccessible(Symbol sym, PackageSymbol packge) {
4337 try {
4338 int flags = (int)(sym.flags() & AccessFlags);
4339 switch (flags) {
4340 default:
4341 case PUBLIC:
4342 return true;
4343 case PRIVATE:
4344 return false;
4345 case 0:
4346 case PROTECTED:
4347 return sym.packge() == packge;
4348 }
4349 } catch (ClassFinder.BadClassFile err) {
4350 throw err;
4351 } catch (CompletionFailure ex) {
4352 return false;
4353 }
4354 }
4355
4356 public void checkLeaksNotAccessible(Env<AttrContext> env, JCClassDecl check) {
4357 JCCompilationUnit toplevel = env.toplevel;
4358
4359 if ( toplevel.modle == syms.unnamedModule
4360 || toplevel.modle == syms.noModule
4361 || (check.sym.flags() & COMPOUND) != 0) {
4362 return ;
4363 }
4364
4365 ExportsDirective currentExport = findExport(toplevel.packge);
4366
4367 if ( currentExport == null //not exported
4368 || currentExport.modules != null) //don't check classes in qualified export
4369 return ;
4370
4371 new TreeScanner() {
4372 Lint lint = env.info.lint;
4373 boolean inSuperType;
4374
4375 @Override
4376 public void visitBlock(JCBlock tree) {
4377 }
4378 @Override
4379 public void visitMethodDef(JCMethodDecl tree) {
4380 if (!isAPISymbol(tree.sym))
4381 return;
4382 Lint prevLint = lint;
4383 try {
4384 lint = lint.augment(tree.sym);
4385 if (lint.isEnabled(LintCategory.EXPORTS)) {
4386 super.visitMethodDef(tree);
4387 }
4388 } finally {
4389 lint = prevLint;
4390 }
4391 }
4392 @Override
4393 public void visitVarDef(JCVariableDecl tree) {
4394 if (!isAPISymbol(tree.sym) && tree.sym.owner.kind != MTH)
4395 return;
4396 Lint prevLint = lint;
4397 try {
4398 lint = lint.augment(tree.sym);
4399 if (lint.isEnabled(LintCategory.EXPORTS)) {
4400 scan(tree.mods);
4401 scan(tree.vartype);
4402 }
4403 } finally {
4404 lint = prevLint;
4405 }
4406 }
4407 @Override
4408 public void visitClassDef(JCClassDecl tree) {
4409 if (tree != check)
4410 return ;
4411
4412 if (!isAPISymbol(tree.sym))
4413 return ;
4414
4415 Lint prevLint = lint;
4416 try {
4417 lint = lint.augment(tree.sym);
4418 if (lint.isEnabled(LintCategory.EXPORTS)) {
4419 scan(tree.mods);
4420 scan(tree.typarams);
4421 try {
4422 inSuperType = true;
4423 scan(tree.extending);
4424 scan(tree.implementing);
4425 } finally {
4426 inSuperType = false;
4427 }
4428 scan(tree.defs);
4429 }
4430 } finally {
4431 lint = prevLint;
4432 }
4433 }
4434 @Override
4435 public void visitTypeApply(JCTypeApply tree) {
4436 scan(tree.clazz);
4437 boolean oldInSuperType = inSuperType;
4438 try {
4439 inSuperType = false;
4440 scan(tree.arguments);
4441 } finally {
4442 inSuperType = oldInSuperType;
4443 }
4444 }
4445 @Override
4446 public void visitIdent(JCIdent tree) {
4447 Symbol sym = TreeInfo.symbol(tree);
4448 if (sym.kind == TYP && !sym.type.hasTag(TYPEVAR)) {
4449 checkVisible(tree.pos(), sym, toplevel.packge, inSuperType);
4450 }
4451 }
4452
4453 @Override
4454 public void visitSelect(JCFieldAccess tree) {
4455 Symbol sym = TreeInfo.symbol(tree);
4456 Symbol sitesym = TreeInfo.symbol(tree.selected);
4457 if (sym.kind == TYP && sitesym.kind == PCK) {
4458 checkVisible(tree.pos(), sym, toplevel.packge, inSuperType);
4459 } else {
4460 super.visitSelect(tree);
4461 }
4462 }
4463
4464 @Override
4465 public void visitAnnotation(JCAnnotation tree) {
4466 if (tree.attribute.type.tsym.getAnnotation(java.lang.annotation.Documented.class) != null)
4467 super.visitAnnotation(tree);
4468 }
4469
4470 }.scan(check);
4471 }
4472 //where:
4473 private ExportsDirective findExport(PackageSymbol pack) {
4474 for (ExportsDirective d : pack.modle.exports) {
4475 if (d.packge == pack)
4476 return d;
4477 }
4478
4479 return null;
4480 }
4481 private boolean isAPISymbol(Symbol sym) {
4482 while (sym.kind != PCK) {
4483 if ((sym.flags() & Flags.PUBLIC) == 0 && (sym.flags() & Flags.PROTECTED) == 0) {
4484 return false;
4485 }
4486 sym = sym.owner;
4487 }
4488 return true;
4489 }
4490 private void checkVisible(DiagnosticPosition pos, Symbol what, PackageSymbol inPackage, boolean inSuperType) {
4491 if (!isAPISymbol(what) && !inSuperType) { //package private/private element
4492 log.warning(LintCategory.EXPORTS, pos, Warnings.LeaksNotAccessible(kindName(what), what, what.packge().modle));
4493 return ;
4494 }
4495
4496 PackageSymbol whatPackage = what.packge();
4497 ExportsDirective whatExport = findExport(whatPackage);
4498 ExportsDirective inExport = findExport(inPackage);
4499
4500 if (whatExport == null) { //package not exported:
4501 log.warning(LintCategory.EXPORTS, pos, Warnings.LeaksNotAccessibleUnexported(kindName(what), what, what.packge().modle));
4502 return ;
4503 }
4504
4505 if (whatExport.modules != null) {
4506 if (inExport.modules == null || !whatExport.modules.containsAll(inExport.modules)) {
4507 log.warning(LintCategory.EXPORTS, pos, Warnings.LeaksNotAccessibleUnexportedQualified(kindName(what), what, what.packge().modle));
4508 }
4509 }
4510
4511 if (whatPackage.modle != inPackage.modle && whatPackage.modle != syms.java_base) {
4512 //check that relativeTo.modle requires transitive what.modle, somehow:
4513 List<ModuleSymbol> todo = List.of(inPackage.modle);
4514
4515 while (todo.nonEmpty()) {
4516 ModuleSymbol current = todo.head;
4517 todo = todo.tail;
4518 if (current == whatPackage.modle)
4519 return ; //OK
4520 if ((current.flags() & Flags.AUTOMATIC_MODULE) != 0)
4521 continue; //for automatic modules, don't look into their dependencies
4522 for (RequiresDirective req : current.requires) {
4523 if (req.isTransitive()) {
4524 todo = todo.prepend(req.module);
4525 }
4526 }
4527 }
4528
4529 log.warning(LintCategory.EXPORTS, pos, Warnings.LeaksNotAccessibleNotRequiredTransitive(kindName(what), what, what.packge().modle));
4530 }
4531 }
4532
4533 void checkModuleExists(final DiagnosticPosition pos, ModuleSymbol msym) {
4534 if (msym.kind != MDL) {
4535 deferredLintHandler.report(() -> {
4536 if (lint.isEnabled(LintCategory.MODULE))
4537 log.warning(LintCategory.MODULE, pos, Warnings.ModuleNotFound(msym));
4538 });
4539 }
4540 }
4541
4542 void checkPackageExistsForOpens(final DiagnosticPosition pos, PackageSymbol packge) {
4543 if (packge.members().isEmpty() &&
4544 ((packge.flags() & Flags.HAS_RESOURCE) == 0)) {
4545 deferredLintHandler.report(() -> {
4546 if (lint.isEnabled(LintCategory.OPENS))
4547 log.warning(pos, Warnings.PackageEmptyOrNotFound(packge));
4548 });
4549 }
4550 }
4551
4552 void checkModuleRequires(final DiagnosticPosition pos, final RequiresDirective rd) {
4553 if ((rd.module.flags() & Flags.AUTOMATIC_MODULE) != 0) {
4554 deferredLintHandler.report(() -> {
4555 if (rd.isTransitive() && lint.isEnabled(LintCategory.REQUIRES_TRANSITIVE_AUTOMATIC)) {
4556 log.warning(pos, Warnings.RequiresTransitiveAutomatic);
4557 } else if (lint.isEnabled(LintCategory.REQUIRES_AUTOMATIC)) {
4558 log.warning(pos, Warnings.RequiresAutomatic);
4559 }
4560 });
4561 }
4562 }
4563
4564 /**
4565 * Verify the case labels conform to the constraints. Checks constraints related
4566 * combinations of patterns and other labels.
4567 *
4568 * @param cases the cases that should be checked.
4569 */
4570 void checkSwitchCaseStructure(List<JCCase> cases) {
4571 boolean wasConstant = false; // Seen a constant in the same case label
4572 boolean wasDefault = false; // Seen a default in the same case label
4573 boolean wasNullPattern = false; // Seen a null pattern in the same case label,
4574 //or fall through from a null pattern
4575 boolean wasPattern = false; // Seen a pattern in the same case label
4576 //or fall through from a pattern
4577 boolean wasTypePattern = false; // Seen a pattern in the same case label
4578 //or fall through from a type pattern
4579 boolean wasNonEmptyFallThrough = false;
4580 for (List<JCCase> l = cases; l.nonEmpty(); l = l.tail) {
4581 JCCase c = l.head;
4582 for (JCCaseLabel pat : c.labels) {
4583 if (pat.isExpression()) {
4584 JCExpression expr = (JCExpression) pat;
4585 if (TreeInfo.isNull(expr)) {
4586 if (wasPattern && !wasTypePattern && !wasNonEmptyFallThrough) {
4587 log.error(pat.pos(), Errors.FlowsThroughFromPattern);
4588 }
4589 wasNullPattern = true;
4590 } else {
4591 if (wasPattern && !wasNonEmptyFallThrough) {
4592 log.error(pat.pos(), Errors.FlowsThroughFromPattern);
4593 }
4594 wasConstant = true;
4595 }
4596 } else if (pat.hasTag(DEFAULTCASELABEL)) {
4597 if (wasPattern && !wasNonEmptyFallThrough) {
4598 log.error(pat.pos(), Errors.FlowsThroughFromPattern);
4599 }
4600 wasDefault = true;
4601 } else {
4602 boolean isTypePattern = pat.hasTag(BINDINGPATTERN);
4603 if (wasPattern || wasConstant || wasDefault ||
4604 (wasNullPattern && (!isTypePattern || wasNonEmptyFallThrough))) {
4605 log.error(pat.pos(), Errors.FlowsThroughToPattern);
4606 }
4607 wasPattern = true;
4608 wasTypePattern = isTypePattern;
4609 }
4610 }
4611
4612 boolean completesNormally = c.caseKind == CaseTree.CaseKind.STATEMENT ? c.completesNormally
4613 : false;
4614
4615 if (c.stats.nonEmpty()) {
4616 wasConstant = false;
4617 wasDefault = false;
4618 wasNullPattern &= completesNormally;
4619 wasPattern &= completesNormally;
4620 wasTypePattern &= completesNormally;
4621 }
4622
4623 wasNonEmptyFallThrough = c.stats.nonEmpty() && completesNormally;
4624 }
4625 }
4626
4627 /** check if a type is a subtype of Externalizable, if that is available. */
4628 boolean isExternalizable(Type t) {
4629 try {
4630 syms.externalizableType.complete();
4631 }
4632 catch (CompletionFailure e) {
4633 return false;
4634 }
4635 return types.isSubtype(t, syms.externalizableType);
4636 }
4637
4638 /**
4639 * Check structure of serialization declarations.
4640 */
4641 public void checkSerialStructure(JCClassDecl tree, ClassSymbol c) {
4642 (new SerialTypeVisitor()).visit(c, tree);
4643 }
4644
4645 /**
4646 * This visitor will warn if a serialization-related field or
4647 * method is declared in a suspicious or incorrect way. In
4648 * particular, it will warn for cases where the runtime
4649 * serialization mechanism will silently ignore a mis-declared
4650 * entity.
4651 *
4652 * Distinguished serialization-related fields and methods:
4653 *
4654 * Methods:
4655 *
4656 * private void writeObject(ObjectOutputStream stream) throws IOException
4657 * ANY-ACCESS-MODIFIER Object writeReplace() throws ObjectStreamException
4658 *
4659 * private void readObject(ObjectInputStream stream) throws IOException, ClassNotFoundException
4660 * private void readObjectNoData() throws ObjectStreamException
4661 * ANY-ACCESS-MODIFIER Object readResolve() throws ObjectStreamException
4662 *
4663 * Fields:
4664 *
4665 * private static final long serialVersionUID
4666 * private static final ObjectStreamField[] serialPersistentFields
4667 *
4668 * Externalizable: methods defined on the interface
4669 * public void writeExternal(ObjectOutput) throws IOException
4670 * public void readExternal(ObjectInput) throws IOException
4671 */
4672 private class SerialTypeVisitor extends ElementKindVisitor14<Void, JCClassDecl> {
4673 SerialTypeVisitor() {
4674 this.lint = Check.this.lint;
4675 }
4676
4677 private static final Set<String> serialMethodNames =
4678 Set.of("writeObject", "writeReplace",
4679 "readObject", "readObjectNoData",
4680 "readResolve");
4681
4682 private static final Set<String> serialFieldNames =
4683 Set.of("serialVersionUID", "serialPersistentFields");
4684
4685 // Type of serialPersistentFields
4686 private final Type OSF_TYPE = new Type.ArrayType(syms.objectStreamFieldType, syms.arrayClass);
4687
4688 Lint lint;
4689
4690 @Override
4691 public Void defaultAction(Element e, JCClassDecl p) {
4692 throw new IllegalArgumentException(Objects.requireNonNullElse(e.toString(), ""));
4693 }
4694
4695 @Override
4696 public Void visitType(TypeElement e, JCClassDecl p) {
4697 runUnderLint(e, p, (symbol, param) -> super.visitType(symbol, param));
4698 return null;
4699 }
4700
4701 @Override
4702 public Void visitTypeAsClass(TypeElement e,
4703 JCClassDecl p) {
4704 // Anonymous classes filtered out by caller.
4705
4706 ClassSymbol c = (ClassSymbol)e;
4707
4708 checkCtorAccess(p, c);
4709
4710 // Check for missing serialVersionUID; check *not* done
4711 // for enums or records.
4712 VarSymbol svuidSym = null;
4713 for (Symbol sym : c.members().getSymbolsByName(names.serialVersionUID)) {
4714 if (sym.kind == VAR) {
4715 svuidSym = (VarSymbol)sym;
4716 break;
4717 }
4718 }
4719
4720 if (svuidSym == null) {
4721 log.warning(LintCategory.SERIAL, p.pos(), Warnings.MissingSVUID(c));
4722 }
4723
4724 // Check for serialPersistentFields to gate checks for
4725 // non-serializable non-transient instance fields
4726 boolean serialPersistentFieldsPresent =
4727 c.members()
4728 .getSymbolsByName(names.serialPersistentFields, sym -> sym.kind == VAR)
4729 .iterator()
4730 .hasNext();
4731
4732 // Check declarations of serialization-related methods and
4733 // fields
4734 for(Symbol el : c.getEnclosedElements()) {
4735 runUnderLint(el, p, (enclosed, tree) -> {
4736 String name = null;
4737 switch(enclosed.getKind()) {
4738 case FIELD -> {
4739 if (!serialPersistentFieldsPresent) {
4740 var flags = enclosed.flags();
4741 if ( ((flags & TRANSIENT) == 0) &&
4742 ((flags & STATIC) == 0)) {
4743 Type varType = enclosed.asType();
4744 if (!canBeSerialized(varType)) {
4745 // Note per JLS arrays are
4746 // serializable even if the
4747 // component type is not.
4748 log.warning(LintCategory.SERIAL,
4749 TreeInfo.diagnosticPositionFor(enclosed, tree),
4750 Warnings.NonSerializableInstanceField);
4751 } else if (varType.hasTag(ARRAY)) {
4752 ArrayType arrayType = (ArrayType)varType;
4753 Type elementType = arrayType.elemtype;
4754 while (elementType.hasTag(ARRAY)) {
4755 arrayType = (ArrayType)elementType;
4756 elementType = arrayType.elemtype;
4757 }
4758 if (!canBeSerialized(elementType)) {
4759 log.warning(LintCategory.SERIAL,
4760 TreeInfo.diagnosticPositionFor(enclosed, tree),
4761 Warnings.NonSerializableInstanceFieldArray(elementType));
4762 }
4763 }
4764 }
4765 }
4766
4767 name = enclosed.getSimpleName().toString();
4768 if (serialFieldNames.contains(name)) {
4769 VarSymbol field = (VarSymbol)enclosed;
4770 switch (name) {
4771 case "serialVersionUID" -> checkSerialVersionUID(tree, e, field);
4772 case "serialPersistentFields" -> checkSerialPersistentFields(tree, e, field);
4773 default -> throw new AssertionError();
4774 }
4775 }
4776 }
4777
4778 // Correctly checking the serialization-related
4779 // methods is subtle. For the methods declared to be
4780 // private or directly declared in the class, the
4781 // enclosed elements of the class can be checked in
4782 // turn. However, writeReplace and readResolve can be
4783 // declared in a superclass and inherited. Note that
4784 // the runtime lookup walks the superclass chain
4785 // looking for writeReplace/readResolve via
4786 // Class.getDeclaredMethod. This differs from calling
4787 // Elements.getAllMembers(TypeElement) as the latter
4788 // will also pull in default methods from
4789 // superinterfaces. In other words, the runtime checks
4790 // (which long predate default methods on interfaces)
4791 // do not admit the possibility of inheriting methods
4792 // this way, a difference from general inheritance.
4793
4794 // The current implementation just checks the enclosed
4795 // elements and does not directly check the inherited
4796 // methods. If all the types are being checked this is
4797 // less of a concern; however, there are cases that
4798 // could be missed. In particular, readResolve and
4799 // writeReplace could, in principle, by inherited from
4800 // a non-serializable superclass and thus not checked
4801 // even if compiled with a serializable child class.
4802 case METHOD -> {
4803 var method = (MethodSymbol)enclosed;
4804 name = method.getSimpleName().toString();
4805 if (serialMethodNames.contains(name)) {
4806 switch (name) {
4807 case "writeObject" -> checkWriteObject(tree, e, method);
4808 case "writeReplace" -> checkWriteReplace(tree,e, method);
4809 case "readObject" -> checkReadObject(tree,e, method);
4810 case "readObjectNoData" -> checkReadObjectNoData(tree, e, method);
4811 case "readResolve" -> checkReadResolve(tree, e, method);
4812 default -> throw new AssertionError();
4813 }
4814 }
4815 }
4816 }
4817 });
4818 }
4819
4820 return null;
4821 }
4822
4823 boolean canBeSerialized(Type type) {
4824 return type.isPrimitive() || rs.isSerializable(type);
4825 }
4826
4827 /**
4828 * Check that Externalizable class needs a public no-arg
4829 * constructor.
4830 *
4831 * Check that a Serializable class has access to the no-arg
4832 * constructor of its first nonserializable superclass.
4833 */
4834 private void checkCtorAccess(JCClassDecl tree, ClassSymbol c) {
4835 if (isExternalizable(c.type)) {
4836 for(var sym : c.getEnclosedElements()) {
4837 if (sym.isConstructor() &&
4838 ((sym.flags() & PUBLIC) == PUBLIC)) {
4839 if (((MethodSymbol)sym).getParameters().isEmpty()) {
4840 return;
4841 }
4842 }
4843 }
4844 log.warning(LintCategory.SERIAL, tree.pos(),
4845 Warnings.ExternalizableMissingPublicNoArgCtor);
4846 } else {
4847 // Approximate access to the no-arg constructor up in
4848 // the superclass chain by checking that the
4849 // constructor is not private. This may not handle
4850 // some cross-package situations correctly.
4851 Type superClass = c.getSuperclass();
4852 // java.lang.Object is *not* Serializable so this loop
4853 // should terminate.
4854 while (rs.isSerializable(superClass) ) {
4855 try {
4856 superClass = (Type)((TypeElement)(((DeclaredType)superClass)).asElement()).getSuperclass();
4857 } catch(ClassCastException cce) {
4858 return ; // Don't try to recover
4859 }
4860 }
4861 // Non-Serializable super class
4862 try {
4863 ClassSymbol supertype = ((ClassSymbol)(((DeclaredType)superClass).asElement()));
4864 for(var sym : supertype.getEnclosedElements()) {
4865 if (sym.isConstructor()) {
4866 MethodSymbol ctor = (MethodSymbol)sym;
4867 if (ctor.getParameters().isEmpty()) {
4868 if (((ctor.flags() & PRIVATE) == PRIVATE) ||
4869 // Handle nested classes and implicit this$0
4870 (supertype.getNestingKind() == NestingKind.MEMBER &&
4871 ((supertype.flags() & STATIC) == 0)))
4872 log.warning(LintCategory.SERIAL, tree.pos(),
4873 Warnings.SerializableMissingAccessNoArgCtor(supertype.getQualifiedName()));
4874 }
4875 }
4876 }
4877 } catch (ClassCastException cce) {
4878 return ; // Don't try to recover
4879 }
4880 return;
4881 }
4882 }
4883
4884 private void checkSerialVersionUID(JCClassDecl tree, Element e, VarSymbol svuid) {
4885 // To be effective, serialVersionUID must be marked static
4886 // and final, but private is recommended. But alas, in
4887 // practice there are many non-private serialVersionUID
4888 // fields.
4889 if ((svuid.flags() & (STATIC | FINAL)) !=
4890 (STATIC | FINAL)) {
4891 log.warning(LintCategory.SERIAL,
4892 TreeInfo.diagnosticPositionFor(svuid, tree),
4893 Warnings.ImproperSVUID((Symbol)e));
4894 }
4895
4896 // check svuid has type long
4897 if (!svuid.type.hasTag(LONG)) {
4898 log.warning(LintCategory.SERIAL,
4899 TreeInfo.diagnosticPositionFor(svuid, tree),
4900 Warnings.LongSVUID((Symbol)e));
4901 }
4902
4903 if (svuid.getConstValue() == null)
4904 log.warning(LintCategory.SERIAL,
4905 TreeInfo.diagnosticPositionFor(svuid, tree),
4906 Warnings.ConstantSVUID((Symbol)e));
4907 }
4908
4909 private void checkSerialPersistentFields(JCClassDecl tree, Element e, VarSymbol spf) {
4910 // To be effective, serialPersisentFields must be private, static, and final.
4911 if ((spf.flags() & (PRIVATE | STATIC | FINAL)) !=
4912 (PRIVATE | STATIC | FINAL)) {
4913 log.warning(LintCategory.SERIAL,
4914 TreeInfo.diagnosticPositionFor(spf, tree), Warnings.ImproperSPF);
4915 }
4916
4917 if (!types.isSameType(spf.type, OSF_TYPE)) {
4918 log.warning(LintCategory.SERIAL,
4919 TreeInfo.diagnosticPositionFor(spf, tree), Warnings.OSFArraySPF);
4920 }
4921
4922 if (isExternalizable((Type)(e.asType()))) {
4923 log.warning(LintCategory.SERIAL, tree.pos(),
4924 Warnings.IneffectualSerialFieldExternalizable);
4925 }
4926
4927 // Warn if serialPersistentFields is initialized to a
4928 // literal null.
4929 JCTree spfDecl = TreeInfo.declarationFor(spf, tree);
4930 if (spfDecl != null && spfDecl.getTag() == VARDEF) {
4931 JCVariableDecl variableDef = (JCVariableDecl) spfDecl;
4932 JCExpression initExpr = variableDef.init;
4933 if (initExpr != null && TreeInfo.isNull(initExpr)) {
4934 log.warning(LintCategory.SERIAL, initExpr.pos(),
4935 Warnings.SPFNullInit);
4936 }
4937 }
4938 }
4939
4940 private void checkWriteObject(JCClassDecl tree, Element e, MethodSymbol method) {
4941 // The "synchronized" modifier is seen in the wild on
4942 // readObject and writeObject methods and is generally
4943 // innocuous.
4944
4945 // private void writeObject(ObjectOutputStream stream) throws IOException
4946 checkPrivateNonStaticMethod(tree, method);
4947 checkReturnType(tree, e, method, syms.voidType);
4948 checkOneArg(tree, e, method, syms.objectOutputStreamType);
4949 checkExceptions(tree, e, method, syms.ioExceptionType);
4950 checkExternalizable(tree, e, method);
4951 }
4952
4953 private void checkWriteReplace(JCClassDecl tree, Element e, MethodSymbol method) {
4954 // ANY-ACCESS-MODIFIER Object writeReplace() throws
4955 // ObjectStreamException
4956
4957 // Excluding abstract, could have a more complicated
4958 // rule based on abstract-ness of the class
4959 checkConcreteInstanceMethod(tree, e, method);
4960 checkReturnType(tree, e, method, syms.objectType);
4961 checkNoArgs(tree, e, method);
4962 checkExceptions(tree, e, method, syms.objectStreamExceptionType);
4963 }
4964
4965 private void checkReadObject(JCClassDecl tree, Element e, MethodSymbol method) {
4966 // The "synchronized" modifier is seen in the wild on
4967 // readObject and writeObject methods and is generally
4968 // innocuous.
4969
4970 // private void readObject(ObjectInputStream stream)
4971 // throws IOException, ClassNotFoundException
4972 checkPrivateNonStaticMethod(tree, method);
4973 checkReturnType(tree, e, method, syms.voidType);
4974 checkOneArg(tree, e, method, syms.objectInputStreamType);
4975 checkExceptions(tree, e, method, syms.ioExceptionType, syms.classNotFoundExceptionType);
4976 checkExternalizable(tree, e, method);
4977 }
4978
4979 private void checkReadObjectNoData(JCClassDecl tree, Element e, MethodSymbol method) {
4980 // private void readObjectNoData() throws ObjectStreamException
4981 checkPrivateNonStaticMethod(tree, method);
4982 checkReturnType(tree, e, method, syms.voidType);
4983 checkNoArgs(tree, e, method);
4984 checkExceptions(tree, e, method, syms.objectStreamExceptionType);
4985 checkExternalizable(tree, e, method);
4986 }
4987
4988 private void checkReadResolve(JCClassDecl tree, Element e, MethodSymbol method) {
4989 // ANY-ACCESS-MODIFIER Object readResolve()
4990 // throws ObjectStreamException
4991
4992 // Excluding abstract, could have a more complicated
4993 // rule based on abstract-ness of the class
4994 checkConcreteInstanceMethod(tree, e, method);
4995 checkReturnType(tree,e, method, syms.objectType);
4996 checkNoArgs(tree, e, method);
4997 checkExceptions(tree, e, method, syms.objectStreamExceptionType);
4998 }
4999
5000 void checkPrivateNonStaticMethod(JCClassDecl tree, MethodSymbol method) {
5001 var flags = method.flags();
5002 if ((flags & PRIVATE) == 0) {
5003 log.warning(LintCategory.SERIAL,
5004 TreeInfo.diagnosticPositionFor(method, tree),
5005 Warnings.SerialMethodNotPrivate(method.getSimpleName()));
5006 }
5007
5008 if ((flags & STATIC) != 0) {
5009 log.warning(LintCategory.SERIAL,
5010 TreeInfo.diagnosticPositionFor(method, tree),
5011 Warnings.SerialMethodStatic(method.getSimpleName()));
5012 }
5013 }
5014
5015 /**
5016 * Per section 1.12 "Serialization of Enum Constants" of
5017 * the serialization specification, due to the special
5018 * serialization handling of enums, any writeObject,
5019 * readObject, writeReplace, and readResolve methods are
5020 * ignored as are serialPersistentFields and
5021 * serialVersionUID fields.
5022 */
5023 @Override
5024 public Void visitTypeAsEnum(TypeElement e,
5025 JCClassDecl p) {
5026 for(Element el : e.getEnclosedElements()) {
5027 runUnderLint(el, p, (enclosed, tree) -> {
5028 String name = enclosed.getSimpleName().toString();
5029 switch(enclosed.getKind()) {
5030 case FIELD -> {
5031 if (serialFieldNames.contains(name)) {
5032 log.warning(LintCategory.SERIAL, tree.pos(),
5033 Warnings.IneffectualSerialFieldEnum(name));
5034 }
5035 }
5036
5037 case METHOD -> {
5038 if (serialMethodNames.contains(name)) {
5039 log.warning(LintCategory.SERIAL, tree.pos(),
5040 Warnings.IneffectualSerialMethodEnum(name));
5041 }
5042 }
5043 }
5044 });
5045 }
5046 return null;
5047 }
5048
5049 /**
5050 * Most serialization-related fields and methods on interfaces
5051 * are ineffectual or problematic.
5052 */
5053 @Override
5054 public Void visitTypeAsInterface(TypeElement e,
5055 JCClassDecl p) {
5056 for(Element el : e.getEnclosedElements()) {
5057 runUnderLint(el, p, (enclosed, tree) -> {
5058 String name = null;
5059 switch(enclosed.getKind()) {
5060 case FIELD -> {
5061 var field = (VarSymbol)enclosed;
5062 name = field.getSimpleName().toString();
5063 switch(name) {
5064 case "serialPersistentFields" -> {
5065 log.warning(LintCategory.SERIAL,
5066 TreeInfo.diagnosticPositionFor(field, tree),
5067 Warnings.IneffectualSerialFieldInterface);
5068 }
5069
5070 case "serialVersionUID" -> {
5071 checkSerialVersionUID(tree, e, field);
5072 }
5073 }
5074 }
5075
5076 case METHOD -> {
5077 var method = (MethodSymbol)enclosed;
5078 name = enclosed.getSimpleName().toString();
5079 if (serialMethodNames.contains(name)) {
5080 switch (name) {
5081 case
5082 "readObject",
5083 "readObjectNoData",
5084 "writeObject" -> checkPrivateMethod(tree, e, method);
5085
5086 case
5087 "writeReplace",
5088 "readResolve" -> checkDefaultIneffective(tree, e, method);
5089
5090 default -> throw new AssertionError();
5091 }
5092
5093 }
5094 }
5095 }
5096 });
5097 }
5098
5099 return null;
5100 }
5101
5102 private void checkPrivateMethod(JCClassDecl tree,
5103 Element e,
5104 MethodSymbol method) {
5105 if ((method.flags() & PRIVATE) == 0) {
5106 log.warning(LintCategory.SERIAL,
5107 TreeInfo.diagnosticPositionFor(method, tree),
5108 Warnings.NonPrivateMethodWeakerAccess);
5109 }
5110 }
5111
5112 private void checkDefaultIneffective(JCClassDecl tree,
5113 Element e,
5114 MethodSymbol method) {
5115 if ((method.flags() & DEFAULT) == DEFAULT) {
5116 log.warning(LintCategory.SERIAL,
5117 TreeInfo.diagnosticPositionFor(method, tree),
5118 Warnings.DefaultIneffective);
5119
5120 }
5121 }
5122
5123 @Override
5124 public Void visitTypeAsAnnotationType(TypeElement e,
5125 JCClassDecl p) {
5126 // Per the JLS, annotation types are not serializeable
5127 return null;
5128 }
5129
5130 /**
5131 * From the Java Object Serialization Specification, 1.13
5132 * Serialization of Records:
5133 *
5134 * "The process by which record objects are serialized or
5135 * externalized cannot be customized; any class-specific
5136 * writeObject, readObject, readObjectNoData, writeExternal,
5137 * and readExternal methods defined by record classes are
5138 * ignored during serialization and deserialization. However,
5139 * a substitute object to be serialized or a designate
5140 * replacement may be specified, by the writeReplace and
5141 * readResolve methods, respectively. Any
5142 * serialPersistentFields field declaration is
5143 * ignored. Documenting serializable fields and data for
5144 * record classes is unnecessary, since there is no variation
5145 * in the serial form, other than whether a substitute or
5146 * replacement object is used. The serialVersionUID of a
5147 * record class is 0L unless explicitly declared. The
5148 * requirement for matching serialVersionUID values is waived
5149 * for record classes."
5150 */
5151 @Override
5152 public Void visitTypeAsRecord(TypeElement e,
5153 JCClassDecl p) {
5154 for(Element el : e.getEnclosedElements()) {
5155 runUnderLint(el, p, (enclosed, tree) -> {
5156 String name = enclosed.getSimpleName().toString();
5157 switch(enclosed.getKind()) {
5158 case FIELD -> {
5159 switch(name) {
5160 case "serialPersistentFields" -> {
5161 log.warning(LintCategory.SERIAL, tree.pos(),
5162 Warnings.IneffectualSerialFieldRecord);
5163 }
5164
5165 case "serialVersionUID" -> {
5166 // Could generate additional warning that
5167 // svuid value is not checked to match for
5168 // records.
5169 checkSerialVersionUID(tree, e, (VarSymbol)enclosed);
5170 }
5171
5172 }
5173 }
5174
5175 case METHOD -> {
5176 var method = (MethodSymbol)enclosed;
5177 switch(name) {
5178 case "writeReplace" -> checkWriteReplace(tree, e, method);
5179 case "readResolve" -> checkReadResolve(tree, e, method);
5180 default -> {
5181 if (serialMethodNames.contains(name)) {
5182 log.warning(LintCategory.SERIAL, tree.pos(),
5183 Warnings.IneffectualSerialMethodRecord(name));
5184 }
5185 }
5186 }
5187
5188 }
5189 }
5190 });
5191 }
5192 return null;
5193 }
5194
5195 void checkConcreteInstanceMethod(JCClassDecl tree,
5196 Element enclosing,
5197 MethodSymbol method) {
5198 if ((method.flags() & (STATIC | ABSTRACT)) != 0) {
5199 log.warning(LintCategory.SERIAL,
5200 TreeInfo.diagnosticPositionFor(method, tree),
5201 Warnings.SerialConcreteInstanceMethod(method.getSimpleName()));
5202 }
5203 }
5204
5205 private void checkReturnType(JCClassDecl tree,
5206 Element enclosing,
5207 MethodSymbol method,
5208 Type expectedReturnType) {
5209 // Note: there may be complications checking writeReplace
5210 // and readResolve since they return Object and could, in
5211 // principle, have covariant overrides and any synthetic
5212 // bridge method would not be represented here for
5213 // checking.
5214 Type rtype = method.getReturnType();
5215 if (!types.isSameType(expectedReturnType, rtype)) {
5216 log.warning(LintCategory.SERIAL,
5217 TreeInfo.diagnosticPositionFor(method, tree),
5218 Warnings.SerialMethodUnexpectedReturnType(method.getSimpleName(),
5219 rtype, expectedReturnType));
5220 }
5221 }
5222
5223 private void checkOneArg(JCClassDecl tree,
5224 Element enclosing,
5225 MethodSymbol method,
5226 Type expectedType) {
5227 String name = method.getSimpleName().toString();
5228
5229 var parameters= method.getParameters();
5230
5231 if (parameters.size() != 1) {
5232 log.warning(LintCategory.SERIAL,
5233 TreeInfo.diagnosticPositionFor(method, tree),
5234 Warnings.SerialMethodOneArg(method.getSimpleName(), parameters.size()));
5235 return;
5236 }
5237
5238 Type parameterType = parameters.get(0).asType();
5239 if (!types.isSameType(parameterType, expectedType)) {
5240 log.warning(LintCategory.SERIAL,
5241 TreeInfo.diagnosticPositionFor(method, tree),
5242 Warnings.SerialMethodParameterType(method.getSimpleName(),
5243 expectedType,
5244 parameterType));
5245 }
5246 }
5247
5248 private void checkNoArgs(JCClassDecl tree, Element enclosing, MethodSymbol method) {
5249 var parameters = method.getParameters();
5250 if (!parameters.isEmpty()) {
5251 log.warning(LintCategory.SERIAL,
5252 TreeInfo.diagnosticPositionFor(parameters.get(0), tree),
5253 Warnings.SerialMethodNoArgs(method.getSimpleName()));
5254 }
5255 }
5256
5257 private void checkExternalizable(JCClassDecl tree, Element enclosing, MethodSymbol method) {
5258 // If the enclosing class is externalizable, warn for the method
5259 if (isExternalizable((Type)enclosing.asType())) {
5260 log.warning(LintCategory.SERIAL, tree.pos(),
5261 Warnings.IneffectualSerialMethodExternalizable(method.getSimpleName()));
5262 }
5263 return;
5264 }
5265
5266 private void checkExceptions(JCClassDecl tree,
5267 Element enclosing,
5268 MethodSymbol method,
5269 Type... declaredExceptions) {
5270 for (Type thrownType: method.getThrownTypes()) {
5271 // For each exception in the throws clause of the
5272 // method, if not an Error and not a RuntimeException,
5273 // check if the exception is a subtype of a declared
5274 // exception from the throws clause of the
5275 // serialization method in question.
5276 if (types.isSubtype(thrownType, syms.runtimeExceptionType) ||
5277 types.isSubtype(thrownType, syms.errorType) ) {
5278 continue;
5279 } else {
5280 boolean declared = false;
5281 for (Type declaredException : declaredExceptions) {
5282 if (types.isSubtype(thrownType, declaredException)) {
5283 declared = true;
5284 continue;
5285 }
5286 }
5287 if (!declared) {
5288 log.warning(LintCategory.SERIAL,
5289 TreeInfo.diagnosticPositionFor(method, tree),
5290 Warnings.SerialMethodUnexpectedException(method.getSimpleName(),
5291 thrownType));
5292 }
5293 }
5294 }
5295 return;
5296 }
5297
5298 private <E extends Element> Void runUnderLint(E symbol, JCClassDecl p, BiConsumer<E, JCClassDecl> task) {
5299 Lint prevLint = lint;
5300 try {
5301 lint = lint.augment((Symbol) symbol);
5302
5303 if (lint.isEnabled(LintCategory.SERIAL)) {
5304 task.accept(symbol, p);
5305 }
5306
5307 return null;
5308 } finally {
5309 lint = prevLint;
5310 }
5311 }
5312
5313 }
5314
5315 }