1 /*
2 * Copyright (c) 1999, 2023, 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.BiPredicate;
31 import java.util.function.Consumer;
32 import java.util.function.Predicate;
33 import java.util.function.Supplier;
34 import java.util.function.ToIntBiFunction;
35 import java.util.stream.Collectors;
36 import java.util.stream.StreamSupport;
37
38 import javax.lang.model.element.ElementKind;
39 import javax.lang.model.element.NestingKind;
40 import javax.tools.JavaFileManager;
41
42 import com.sun.source.tree.CaseTree;
43 import com.sun.tools.javac.code.*;
44 import com.sun.tools.javac.code.Attribute.Compound;
45 import com.sun.tools.javac.code.Directive.ExportsDirective;
46 import com.sun.tools.javac.code.Directive.RequiresDirective;
47 import com.sun.tools.javac.code.Source.Feature;
48 import com.sun.tools.javac.comp.Annotate.AnnotationTypeMetadata;
49 import com.sun.tools.javac.jvm.*;
50 import com.sun.tools.javac.resources.CompilerProperties.Errors;
51 import com.sun.tools.javac.resources.CompilerProperties.Fragments;
52 import com.sun.tools.javac.resources.CompilerProperties.Warnings;
53 import com.sun.tools.javac.tree.*;
54 import com.sun.tools.javac.util.*;
55 import com.sun.tools.javac.util.JCDiagnostic.DiagnosticFlag;
56 import com.sun.tools.javac.util.JCDiagnostic.DiagnosticPosition;
57 import com.sun.tools.javac.util.JCDiagnostic.Error;
58 import com.sun.tools.javac.util.JCDiagnostic.Fragment;
59 import com.sun.tools.javac.util.JCDiagnostic.Warning;
60 import com.sun.tools.javac.util.List;
61
62 import com.sun.tools.javac.code.Lint;
63 import com.sun.tools.javac.code.Lint.LintCategory;
64 import com.sun.tools.javac.code.Scope.WriteableScope;
65 import com.sun.tools.javac.code.Type.*;
66 import com.sun.tools.javac.code.Symbol.*;
67 import com.sun.tools.javac.comp.DeferredAttr.DeferredAttrContext;
68 import com.sun.tools.javac.tree.JCTree.*;
69
70 import static com.sun.tools.javac.code.Flags.*;
71 import static com.sun.tools.javac.code.Flags.ANNOTATION;
72 import static com.sun.tools.javac.code.Flags.SYNCHRONIZED;
73 import static com.sun.tools.javac.code.Kinds.*;
74 import static com.sun.tools.javac.code.Kinds.Kind.*;
75 import static com.sun.tools.javac.code.Scope.LookupKind.NON_RECURSIVE;
76 import static com.sun.tools.javac.code.Scope.LookupKind.RECURSIVE;
77 import static com.sun.tools.javac.code.TypeTag.*;
78 import static com.sun.tools.javac.code.TypeTag.WILDCARD;
79
80 import static com.sun.tools.javac.tree.JCTree.Tag.*;
81 import javax.lang.model.element.Element;
82 import javax.lang.model.element.ExecutableElement;
83 import javax.lang.model.element.TypeElement;
84 import javax.lang.model.type.DeclaredType;
85 import javax.lang.model.type.TypeMirror;
86 import javax.lang.model.util.ElementFilter;
87 import javax.lang.model.util.ElementKindVisitor14;
88
89 /** Type checking helper class for the attribution phase.
90 *
91 * <p><b>This is NOT part of any supported API.
92 * If you write code that depends on this, you do so at your own risk.
93 * This code and its internal interfaces are subject to change or
94 * deletion without notice.</b>
95 */
96 public class Check {
97 protected static final Context.Key<Check> checkKey = new Context.Key<>();
98
99 // Flag bits indicating which item(s) chosen from a pair of items
100 private static final int FIRST = 0x01;
101 private static final int SECOND = 0x02;
102
103 private final Names names;
104 private final Log log;
105 private final Resolve rs;
106 private final Symtab syms;
107 private final Enter enter;
108 private final DeferredAttr deferredAttr;
109 private final Infer infer;
110 private final Types types;
111 private final TypeAnnotations typeAnnotations;
112 private final JCDiagnostic.Factory diags;
113 private final JavaFileManager fileManager;
114 private final Source source;
115 private final Target target;
116 private final Profile profile;
117 private final Preview preview;
118 private final boolean warnOnAnyAccessToMembers;
119
120 public boolean disablePreviewCheck;
121
122 // The set of lint options currently in effect. It is initialized
123 // from the context, and then is set/reset as needed by Attr as it
124 // visits all the various parts of the trees during attribution.
125 private Lint lint;
126
127 // The method being analyzed in Attr - it is set/reset as needed by
128 // Attr as it visits new method declarations.
129 private MethodSymbol method;
130
131 public static Check instance(Context context) {
132 Check instance = context.get(checkKey);
133 if (instance == null)
134 instance = new Check(context);
135 return instance;
136 }
137
138 @SuppressWarnings("this-escape")
139 protected Check(Context context) {
140 context.put(checkKey, this);
141
142 names = Names.instance(context);
143 log = Log.instance(context);
144 rs = Resolve.instance(context);
145 syms = Symtab.instance(context);
146 enter = Enter.instance(context);
147 deferredAttr = DeferredAttr.instance(context);
148 infer = Infer.instance(context);
149 types = Types.instance(context);
150 typeAnnotations = TypeAnnotations.instance(context);
151 diags = JCDiagnostic.Factory.instance(context);
152 Options options = Options.instance(context);
153 lint = Lint.instance(context);
154 fileManager = context.get(JavaFileManager.class);
155
156 source = Source.instance(context);
157 target = Target.instance(context);
158 warnOnAnyAccessToMembers = options.isSet("warnOnAccessToMembers");
159
160 disablePreviewCheck = false;
161
162 Target target = Target.instance(context);
163 syntheticNameChar = target.syntheticNameChar();
164
165 profile = Profile.instance(context);
166 preview = Preview.instance(context);
167
168 boolean verboseDeprecated = lint.isEnabled(LintCategory.DEPRECATION);
169 boolean verboseRemoval = lint.isEnabled(LintCategory.REMOVAL);
170 boolean verboseUnchecked = lint.isEnabled(LintCategory.UNCHECKED);
171 boolean enforceMandatoryWarnings = true;
172
173 deprecationHandler = new MandatoryWarningHandler(log, null, verboseDeprecated,
174 enforceMandatoryWarnings, "deprecated", LintCategory.DEPRECATION);
175 removalHandler = new MandatoryWarningHandler(log, null, verboseRemoval,
176 enforceMandatoryWarnings, "removal", LintCategory.REMOVAL);
177 uncheckedHandler = new MandatoryWarningHandler(log, null, verboseUnchecked,
178 enforceMandatoryWarnings, "unchecked", LintCategory.UNCHECKED);
179 sunApiHandler = new MandatoryWarningHandler(log, null, false,
180 enforceMandatoryWarnings, "sunapi", null);
181
182 deferredLintHandler = DeferredLintHandler.instance(context);
183
184 allowModules = Feature.MODULES.allowedInSource(source);
185 allowRecords = Feature.RECORDS.allowedInSource(source);
186 allowSealed = Feature.SEALED_CLASSES.allowedInSource(source);
187 }
188
189 /** Character for synthetic names
190 */
191 char syntheticNameChar;
192
193 /** A table mapping flat names of all compiled classes for each module in this run
194 * to their symbols; maintained from outside.
195 */
196 private Map<Pair<ModuleSymbol, Name>,ClassSymbol> compiled = new HashMap<>();
197
198 /** A handler for messages about deprecated usage.
199 */
200 private MandatoryWarningHandler deprecationHandler;
201
202 /** A handler for messages about deprecated-for-removal usage.
203 */
204 private MandatoryWarningHandler removalHandler;
205
206 /** A handler for messages about unchecked or unsafe usage.
207 */
208 private MandatoryWarningHandler uncheckedHandler;
209
210 /** A handler for messages about using proprietary API.
211 */
212 private MandatoryWarningHandler sunApiHandler;
213
214 /** A handler for deferred lint warnings.
215 */
216 private DeferredLintHandler deferredLintHandler;
217
218 /** Are modules allowed
219 */
220 private final boolean allowModules;
221
222 /** Are records allowed
223 */
224 private final boolean allowRecords;
225
226 /** Are sealed classes allowed
227 */
228 private final boolean allowSealed;
229
230 /* *************************************************************************
231 * Errors and Warnings
232 **************************************************************************/
233
234 Lint setLint(Lint newLint) {
235 Lint prev = lint;
236 lint = newLint;
237 return prev;
238 }
239
240 MethodSymbol setMethod(MethodSymbol newMethod) {
241 MethodSymbol prev = method;
242 method = newMethod;
243 return prev;
244 }
245
246 /** Warn about deprecated symbol.
247 * @param pos Position to be used for error reporting.
248 * @param sym The deprecated symbol.
249 */
250 void warnDeprecated(DiagnosticPosition pos, Symbol sym) {
251 if (sym.isDeprecatedForRemoval()) {
252 if (!lint.isSuppressed(LintCategory.REMOVAL)) {
253 if (sym.kind == MDL) {
254 removalHandler.report(pos, Warnings.HasBeenDeprecatedForRemovalModule(sym));
255 } else {
256 removalHandler.report(pos, Warnings.HasBeenDeprecatedForRemoval(sym, sym.location()));
257 }
258 }
259 } else if (!lint.isSuppressed(LintCategory.DEPRECATION)) {
260 if (sym.kind == MDL) {
261 deprecationHandler.report(pos, Warnings.HasBeenDeprecatedModule(sym));
262 } else {
263 deprecationHandler.report(pos, Warnings.HasBeenDeprecated(sym, sym.location()));
264 }
265 }
266 }
267
268 /** Log a preview warning.
269 * @param pos Position to be used for error reporting.
270 * @param msg A Warning describing the problem.
271 */
272 public void warnPreviewAPI(DiagnosticPosition pos, Warning warnKey) {
273 if (!lint.isSuppressed(LintCategory.PREVIEW))
274 preview.reportPreviewWarning(pos, warnKey);
275 }
276
277 /** Log a preview warning.
278 * @param pos Position to be used for error reporting.
279 * @param msg A Warning describing the problem.
280 */
281 public void warnDeclaredUsingPreview(DiagnosticPosition pos, Symbol sym) {
282 if (!lint.isSuppressed(LintCategory.PREVIEW))
283 preview.reportPreviewWarning(pos, Warnings.DeclaredUsingPreview(kindName(sym), sym));
284 }
285
286 /** Warn about unchecked operation.
287 * @param pos Position to be used for error reporting.
288 * @param msg A string describing the problem.
289 */
290 public void warnUnchecked(DiagnosticPosition pos, Warning warnKey) {
291 if (!lint.isSuppressed(LintCategory.UNCHECKED))
292 uncheckedHandler.report(pos, warnKey);
293 }
294
295 /** Warn about unsafe vararg method decl.
296 * @param pos Position to be used for error reporting.
297 */
298 void warnUnsafeVararg(DiagnosticPosition pos, Warning warnKey) {
299 if (lint.isEnabled(LintCategory.VARARGS))
300 log.warning(LintCategory.VARARGS, pos, warnKey);
301 }
302
303 public void warnStatic(DiagnosticPosition pos, Warning warnKey) {
304 if (lint.isEnabled(LintCategory.STATIC))
305 log.warning(LintCategory.STATIC, pos, warnKey);
306 }
307
308 /** Warn about division by integer constant zero.
309 * @param pos Position to be used for error reporting.
310 */
311 void warnDivZero(DiagnosticPosition pos) {
312 if (lint.isEnabled(LintCategory.DIVZERO))
313 log.warning(LintCategory.DIVZERO, pos, Warnings.DivZero);
314 }
315
316 /**
317 * Report any deferred diagnostics.
318 */
319 public void reportDeferredDiagnostics() {
320 deprecationHandler.reportDeferredDiagnostic();
321 removalHandler.reportDeferredDiagnostic();
322 uncheckedHandler.reportDeferredDiagnostic();
323 sunApiHandler.reportDeferredDiagnostic();
324 }
325
326
327 /** Report a failure to complete a class.
328 * @param pos Position to be used for error reporting.
329 * @param ex The failure to report.
330 */
331 public Type completionError(DiagnosticPosition pos, CompletionFailure ex) {
332 log.error(JCDiagnostic.DiagnosticFlag.NON_DEFERRABLE, pos, Errors.CantAccess(ex.sym, ex.getDetailValue()));
333 return syms.errType;
334 }
335
336 /** Report an error that wrong type tag was found.
337 * @param pos Position to be used for error reporting.
338 * @param required An internationalized string describing the type tag
339 * required.
340 * @param found The type that was found.
341 */
342 Type typeTagError(DiagnosticPosition pos, JCDiagnostic required, Object found) {
343 // this error used to be raised by the parser,
344 // but has been delayed to this point:
345 if (found instanceof Type type && type.hasTag(VOID)) {
346 log.error(pos, Errors.IllegalStartOfType);
347 return syms.errType;
348 }
349 log.error(pos, Errors.TypeFoundReq(found, required));
350 return types.createErrorType(found instanceof Type type ? type : syms.errType);
351 }
352
353 /** Report an error that symbol cannot be referenced before super
354 * has been called.
355 * @param pos Position to be used for error reporting.
356 * @param sym The referenced symbol.
357 */
358 void earlyRefError(DiagnosticPosition pos, Symbol sym) {
359 log.error(pos, Errors.CantRefBeforeCtorCalled(sym));
360 }
361
362 /** Report duplicate declaration error.
363 */
364 void duplicateError(DiagnosticPosition pos, Symbol sym) {
365 if (!sym.type.isErroneous()) {
366 Symbol location = sym.location();
367 if (location.kind == MTH &&
368 ((MethodSymbol)location).isStaticOrInstanceInit()) {
369 log.error(pos,
370 Errors.AlreadyDefinedInClinit(kindName(sym),
371 sym,
372 kindName(sym.location()),
373 kindName(sym.location().enclClass()),
374 sym.location().enclClass()));
375 } else {
376 /* dont error if this is a duplicated parameter of a generated canonical constructor
377 * as we should have issued an error for the duplicated fields
378 */
379 if (location.kind != MTH ||
380 ((sym.owner.flags_field & GENERATEDCONSTR) == 0) ||
381 ((sym.owner.flags_field & RECORD) == 0)) {
382 log.error(pos,
383 Errors.AlreadyDefined(kindName(sym),
384 sym,
385 kindName(sym.location()),
386 sym.location()));
387 }
388 }
389 }
390 }
391
392 /** Report array/varargs duplicate declaration
393 */
394 void varargsDuplicateError(DiagnosticPosition pos, Symbol sym1, Symbol sym2) {
395 if (!sym1.type.isErroneous() && !sym2.type.isErroneous()) {
396 log.error(pos, Errors.ArrayAndVarargs(sym1, sym2, sym2.location()));
397 }
398 }
399
400 /* ************************************************************************
401 * duplicate declaration checking
402 *************************************************************************/
403
404 /** Check that variable does not hide variable with same name in
405 * immediately enclosing local scope.
406 * @param pos Position for error reporting.
407 * @param v The symbol.
408 * @param s The scope.
409 */
410 void checkTransparentVar(DiagnosticPosition pos, VarSymbol v, Scope s) {
411 for (Symbol sym : s.getSymbolsByName(v.name)) {
412 if (sym.owner != v.owner) break;
413 if (sym.kind == VAR &&
414 sym.owner.kind.matches(KindSelector.VAL_MTH) &&
415 v.name != names.error) {
416 duplicateError(pos, sym);
417 return;
418 }
419 }
420 }
421
422 /** Check that a class or interface does not hide a class or
423 * interface with same name in immediately enclosing local scope.
424 * @param pos Position for error reporting.
425 * @param c The symbol.
426 * @param s The scope.
427 */
428 void checkTransparentClass(DiagnosticPosition pos, ClassSymbol c, Scope s) {
429 for (Symbol sym : s.getSymbolsByName(c.name)) {
430 if (sym.owner != c.owner) break;
431 if (sym.kind == TYP && !sym.type.hasTag(TYPEVAR) &&
432 sym.owner.kind.matches(KindSelector.VAL_MTH) &&
433 c.name != names.error) {
434 duplicateError(pos, sym);
435 return;
436 }
437 }
438 }
439
440 /** Check that class does not have the same name as one of
441 * its enclosing classes, or as a class defined in its enclosing scope.
442 * return true if class is unique in its enclosing scope.
443 * @param pos Position for error reporting.
444 * @param name The class name.
445 * @param s The enclosing scope.
446 */
447 boolean checkUniqueClassName(DiagnosticPosition pos, Name name, Scope s) {
448 for (Symbol sym : s.getSymbolsByName(name, NON_RECURSIVE)) {
449 if (sym.kind == TYP && sym.name != names.error) {
450 duplicateError(pos, sym);
451 return false;
452 }
453 }
454 for (Symbol sym = s.owner; sym != null; sym = sym.owner) {
455 if (sym.kind == TYP && sym.name == name && sym.name != names.error) {
456 duplicateError(pos, sym);
457 return true;
458 }
459 }
460 return true;
461 }
462
463 /* *************************************************************************
464 * Class name generation
465 **************************************************************************/
466
467
468 private Map<Pair<Name, Name>, Integer> localClassNameIndexes = new HashMap<>();
469
470 /** Return name of local class.
471 * This is of the form {@code <enclClass> $ n <classname> }
472 * where
473 * enclClass is the flat name of the enclosing class,
474 * classname is the simple name of the local class
475 */
476 public Name localClassName(ClassSymbol c) {
477 Name enclFlatname = c.owner.enclClass().flatname;
478 String enclFlatnameStr = enclFlatname.toString();
479 Pair<Name, Name> key = new Pair<>(enclFlatname, c.name);
480 Integer index = localClassNameIndexes.get(key);
481 for (int i = (index == null) ? 1 : index; ; i++) {
482 Name flatname = names.fromString(enclFlatnameStr
483 + syntheticNameChar + i + c.name);
484 if (getCompiled(c.packge().modle, flatname) == null) {
485 localClassNameIndexes.put(key, i + 1);
486 return flatname;
487 }
488 }
489 }
490
491 public void clearLocalClassNameIndexes(ClassSymbol c) {
492 if (c.owner != null && c.owner.kind != NIL) {
493 localClassNameIndexes.remove(new Pair<>(
494 c.owner.enclClass().flatname, c.name));
495 }
496 }
497
498 public void newRound() {
499 compiled.clear();
500 localClassNameIndexes.clear();
501 }
502
503 public void clear() {
504 deprecationHandler.clear();
505 removalHandler.clear();
506 uncheckedHandler.clear();
507 sunApiHandler.clear();
508 }
509
510 public void putCompiled(ClassSymbol csym) {
511 compiled.put(Pair.of(csym.packge().modle, csym.flatname), csym);
512 }
513
514 public ClassSymbol getCompiled(ClassSymbol csym) {
515 return compiled.get(Pair.of(csym.packge().modle, csym.flatname));
516 }
517
518 public ClassSymbol getCompiled(ModuleSymbol msym, Name flatname) {
519 return compiled.get(Pair.of(msym, flatname));
520 }
521
522 public void removeCompiled(ClassSymbol csym) {
523 compiled.remove(Pair.of(csym.packge().modle, csym.flatname));
524 }
525
526 /* *************************************************************************
527 * Type Checking
528 **************************************************************************/
529
530 /**
531 * A check context is an object that can be used to perform compatibility
532 * checks - depending on the check context, meaning of 'compatibility' might
533 * vary significantly.
534 */
535 public interface CheckContext {
536 /**
537 * Is type 'found' compatible with type 'req' in given context
538 */
539 boolean compatible(Type found, Type req, Warner warn);
540 /**
541 * Report a check error
542 */
543 void report(DiagnosticPosition pos, JCDiagnostic details);
544 /**
545 * Obtain a warner for this check context
546 */
547 public Warner checkWarner(DiagnosticPosition pos, Type found, Type req);
548
549 public InferenceContext inferenceContext();
550
551 public DeferredAttr.DeferredAttrContext deferredAttrContext();
552 }
553
554 /**
555 * This class represent a check context that is nested within another check
556 * context - useful to check sub-expressions. The default behavior simply
557 * redirects all method calls to the enclosing check context leveraging
558 * the forwarding pattern.
559 */
560 static class NestedCheckContext implements CheckContext {
561 CheckContext enclosingContext;
562
563 NestedCheckContext(CheckContext enclosingContext) {
564 this.enclosingContext = enclosingContext;
565 }
566
567 public boolean compatible(Type found, Type req, Warner warn) {
568 return enclosingContext.compatible(found, req, warn);
569 }
570
571 public void report(DiagnosticPosition pos, JCDiagnostic details) {
572 enclosingContext.report(pos, details);
573 }
574
575 public Warner checkWarner(DiagnosticPosition pos, Type found, Type req) {
576 return enclosingContext.checkWarner(pos, found, req);
577 }
578
579 public InferenceContext inferenceContext() {
580 return enclosingContext.inferenceContext();
581 }
582
583 public DeferredAttrContext deferredAttrContext() {
584 return enclosingContext.deferredAttrContext();
585 }
586 }
587
588 /**
589 * Check context to be used when evaluating assignment/return statements
590 */
591 CheckContext basicHandler = new CheckContext() {
592 public void report(DiagnosticPosition pos, JCDiagnostic details) {
593 log.error(pos, Errors.ProbFoundReq(details));
594 }
595 public boolean compatible(Type found, Type req, Warner warn) {
596 return types.isAssignable(found, req, warn);
597 }
598
599 public Warner checkWarner(DiagnosticPosition pos, Type found, Type req) {
600 return convertWarner(pos, found, req);
601 }
602
603 public InferenceContext inferenceContext() {
604 return infer.emptyContext;
605 }
606
607 public DeferredAttrContext deferredAttrContext() {
608 return deferredAttr.emptyDeferredAttrContext;
609 }
610
611 @Override
612 public String toString() {
613 return "CheckContext: basicHandler";
614 }
615 };
616
617 /** Check that a given type is assignable to a given proto-type.
618 * If it is, return the type, otherwise return errType.
619 * @param pos Position to be used for error reporting.
620 * @param found The type that was found.
621 * @param req The type that was required.
622 */
623 public Type checkType(DiagnosticPosition pos, Type found, Type req) {
624 return checkType(pos, found, req, basicHandler);
625 }
626
627 Type checkType(final DiagnosticPosition pos, final Type found, final Type req, final CheckContext checkContext) {
628 final InferenceContext inferenceContext = checkContext.inferenceContext();
629 if (inferenceContext.free(req) || inferenceContext.free(found)) {
630 inferenceContext.addFreeTypeListener(List.of(req, found),
631 solvedContext -> checkType(pos, solvedContext.asInstType(found), solvedContext.asInstType(req), checkContext));
632 }
633 if (req.hasTag(ERROR))
634 return req;
635 if (req.hasTag(NONE))
636 return found;
637 if (checkContext.compatible(found, req, checkContext.checkWarner(pos, found, req))) {
638 return found;
639 } else {
640 if (found.isNumeric() && req.isNumeric()) {
641 checkContext.report(pos, diags.fragment(Fragments.PossibleLossOfPrecision(found, req)));
642 return types.createErrorType(found);
643 }
644 checkContext.report(pos, diags.fragment(Fragments.InconvertibleTypes(found, req)));
645 return types.createErrorType(found);
646 }
647 }
648
649 /** Check that a given type can be cast to a given target type.
650 * Return the result of the cast.
651 * @param pos Position to be used for error reporting.
652 * @param found The type that is being cast.
653 * @param req The target type of the cast.
654 */
655 Type checkCastable(DiagnosticPosition pos, Type found, Type req) {
656 return checkCastable(pos, found, req, basicHandler);
657 }
658 Type checkCastable(DiagnosticPosition pos, Type found, Type req, CheckContext checkContext) {
659 if (types.isCastable(found, req, castWarner(pos, found, req))) {
660 return req;
661 } else {
662 checkContext.report(pos, diags.fragment(Fragments.InconvertibleTypes(found, req)));
663 return types.createErrorType(found);
664 }
665 }
666
667 /** Check for redundant casts (i.e. where source type is a subtype of target type)
668 * The problem should only be reported for non-292 cast
669 */
670 public void checkRedundantCast(Env<AttrContext> env, final JCTypeCast tree) {
671 if (!tree.type.isErroneous()
672 && types.isSameType(tree.expr.type, tree.clazz.type)
673 && !(ignoreAnnotatedCasts && TreeInfo.containsTypeAnnotation(tree.clazz))
674 && !is292targetTypeCast(tree)) {
675 deferredLintHandler.report(() -> {
676 if (lint.isEnabled(LintCategory.CAST))
677 log.warning(LintCategory.CAST,
678 tree.pos(), Warnings.RedundantCast(tree.clazz.type));
679 });
680 }
681 }
682 //where
683 private boolean is292targetTypeCast(JCTypeCast tree) {
684 boolean is292targetTypeCast = false;
685 JCExpression expr = TreeInfo.skipParens(tree.expr);
686 if (expr.hasTag(APPLY)) {
687 JCMethodInvocation apply = (JCMethodInvocation)expr;
688 Symbol sym = TreeInfo.symbol(apply.meth);
689 is292targetTypeCast = sym != null &&
690 sym.kind == MTH &&
691 (sym.flags() & HYPOTHETICAL) != 0;
692 }
693 return is292targetTypeCast;
694 }
695
696 private static final boolean ignoreAnnotatedCasts = true;
697
698 /** Check that a type is within some bounds.
699 *
700 * Used in TypeApply to verify that, e.g., X in {@code V<X>} is a valid
701 * type argument.
702 * @param a The type that should be bounded by bs.
703 * @param bound The bound.
704 */
705 private boolean checkExtends(Type a, Type bound) {
706 if (a.isUnbound()) {
707 return true;
708 } else if (!a.hasTag(WILDCARD)) {
709 a = types.cvarUpperBound(a);
710 return types.isSubtype(a, bound);
711 } else if (a.isExtendsBound()) {
712 return types.isCastable(bound, types.wildUpperBound(a), types.noWarnings);
713 } else if (a.isSuperBound()) {
714 return !types.notSoftSubtype(types.wildLowerBound(a), bound);
715 }
716 return true;
717 }
718
719 /** Check that type is different from 'void'.
720 * @param pos Position to be used for error reporting.
721 * @param t The type to be checked.
722 */
723 Type checkNonVoid(DiagnosticPosition pos, Type t) {
724 if (t.hasTag(VOID)) {
725 log.error(pos, Errors.VoidNotAllowedHere);
726 return types.createErrorType(t);
727 } else {
728 return t;
729 }
730 }
731
732 Type checkClassOrArrayType(DiagnosticPosition pos, Type t) {
733 if (!t.hasTag(CLASS) && !t.hasTag(ARRAY) && !t.hasTag(ERROR)) {
734 return typeTagError(pos,
735 diags.fragment(Fragments.TypeReqClassArray),
736 asTypeParam(t));
737 } else {
738 return t;
739 }
740 }
741
742 /** Check that type is a class or interface type.
743 * @param pos Position to be used for error reporting.
744 * @param t The type to be checked.
745 */
746 Type checkClassType(DiagnosticPosition pos, Type t) {
747 if (!t.hasTag(CLASS) && !t.hasTag(ERROR)) {
748 return typeTagError(pos,
749 diags.fragment(Fragments.TypeReqClass),
750 asTypeParam(t));
751 } else {
752 return t;
753 }
754 }
755 //where
756 private Object asTypeParam(Type t) {
757 return (t.hasTag(TYPEVAR))
758 ? diags.fragment(Fragments.TypeParameter(t))
759 : t;
760 }
761
762 /** Check that type is a valid qualifier for a constructor reference expression
763 */
764 Type checkConstructorRefType(DiagnosticPosition pos, Type t) {
765 t = checkClassOrArrayType(pos, t);
766 if (t.hasTag(CLASS)) {
767 if ((t.tsym.flags() & (ABSTRACT | INTERFACE)) != 0) {
768 log.error(pos, Errors.AbstractCantBeInstantiated(t.tsym));
769 t = types.createErrorType(t);
770 } else if ((t.tsym.flags() & ENUM) != 0) {
771 log.error(pos, Errors.EnumCantBeInstantiated);
772 t = types.createErrorType(t);
773 } else {
774 t = checkClassType(pos, t, true);
775 }
776 } else if (t.hasTag(ARRAY)) {
777 if (!types.isReifiable(((ArrayType)t).elemtype)) {
778 log.error(pos, Errors.GenericArrayCreation);
779 t = types.createErrorType(t);
780 }
781 }
782 return t;
783 }
784
785 /** Check that type is a class or interface type.
786 * @param pos Position to be used for error reporting.
787 * @param t The type to be checked.
788 * @param noBounds True if type bounds are illegal here.
789 */
790 Type checkClassType(DiagnosticPosition pos, Type t, boolean noBounds) {
791 t = checkClassType(pos, t);
792 if (noBounds && t.isParameterized()) {
793 List<Type> args = t.getTypeArguments();
794 while (args.nonEmpty()) {
795 if (args.head.hasTag(WILDCARD))
796 return typeTagError(pos,
797 diags.fragment(Fragments.TypeReqExact),
798 args.head);
799 args = args.tail;
800 }
801 }
802 return t;
803 }
804
805 /** Check that type is a reference type, i.e. a class, interface or array type
806 * or a type variable.
807 * @param pos Position to be used for error reporting.
808 * @param t The type to be checked.
809 */
810 Type checkRefType(DiagnosticPosition pos, Type t) {
811 if (t.isReference())
812 return t;
813 else
814 return typeTagError(pos,
815 diags.fragment(Fragments.TypeReqRef),
816 t);
817 }
818
819 /** Check that each type is a reference type, i.e. a class, interface or array type
820 * or a type variable.
821 * @param trees Original trees, used for error reporting.
822 * @param types The types to be checked.
823 */
824 List<Type> checkRefTypes(List<JCExpression> trees, List<Type> types) {
825 List<JCExpression> tl = trees;
826 for (List<Type> l = types; l.nonEmpty(); l = l.tail) {
827 l.head = checkRefType(tl.head.pos(), l.head);
828 tl = tl.tail;
829 }
830 return types;
831 }
832
833 /** Check that type is a null or reference type.
834 * @param pos Position to be used for error reporting.
835 * @param t The type to be checked.
836 */
837 Type checkNullOrRefType(DiagnosticPosition pos, Type t) {
838 if (t.isReference() || t.hasTag(BOT))
839 return t;
840 else
841 return typeTagError(pos,
842 diags.fragment(Fragments.TypeReqRef),
843 t);
844 }
845
846 /** Check that flag set does not contain elements of two conflicting sets. s
847 * Return true if it doesn't.
848 * @param pos Position to be used for error reporting.
849 * @param flags The set of flags to be checked.
850 * @param set1 Conflicting flags set #1.
851 * @param set2 Conflicting flags set #2.
852 */
853 boolean checkDisjoint(DiagnosticPosition pos, long flags, long set1, long set2) {
854 if ((flags & set1) != 0 && (flags & set2) != 0) {
855 log.error(pos,
856 Errors.IllegalCombinationOfModifiers(asFlagSet(TreeInfo.firstFlag(flags & set1)),
857 asFlagSet(TreeInfo.firstFlag(flags & set2))));
858 return false;
859 } else
860 return true;
861 }
862
863 /** Check that usage of diamond operator is correct (i.e. diamond should not
864 * be used with non-generic classes or in anonymous class creation expressions)
865 */
866 Type checkDiamond(JCNewClass tree, Type t) {
867 if (!TreeInfo.isDiamond(tree) ||
868 t.isErroneous()) {
869 return checkClassType(tree.clazz.pos(), t, true);
870 } else {
871 if (tree.def != null && !Feature.DIAMOND_WITH_ANONYMOUS_CLASS_CREATION.allowedInSource(source)) {
872 log.error(DiagnosticFlag.SOURCE_LEVEL, tree.clazz.pos(),
873 Errors.CantApplyDiamond1(t, Feature.DIAMOND_WITH_ANONYMOUS_CLASS_CREATION.fragment(source.name)));
874 }
875 if (t.tsym.type.getTypeArguments().isEmpty()) {
876 log.error(tree.clazz.pos(),
877 Errors.CantApplyDiamond1(t,
878 Fragments.DiamondNonGeneric(t)));
879 return types.createErrorType(t);
880 } else if (tree.typeargs != null &&
881 tree.typeargs.nonEmpty()) {
882 log.error(tree.clazz.pos(),
883 Errors.CantApplyDiamond1(t,
884 Fragments.DiamondAndExplicitParams(t)));
885 return types.createErrorType(t);
886 } else {
887 return t;
888 }
889 }
890 }
891
892 /** Check that the type inferred using the diamond operator does not contain
893 * non-denotable types such as captured types or intersection types.
894 * @param t the type inferred using the diamond operator
895 * @return the (possibly empty) list of non-denotable types.
896 */
897 List<Type> checkDiamondDenotable(ClassType t) {
898 ListBuffer<Type> buf = new ListBuffer<>();
899 for (Type arg : t.allparams()) {
900 if (!checkDenotable(arg)) {
901 buf.append(arg);
902 }
903 }
904 return buf.toList();
905 }
906
907 public boolean checkDenotable(Type t) {
908 return denotableChecker.visit(t, null);
909 }
910 // where
911
912 /** diamondTypeChecker: A type visitor that descends down the given type looking for non-denotable
913 * types. The visit methods return false as soon as a non-denotable type is encountered and true
914 * otherwise.
915 */
916 private static final Types.SimpleVisitor<Boolean, Void> denotableChecker = new Types.SimpleVisitor<Boolean, Void>() {
917 @Override
918 public Boolean visitType(Type t, Void s) {
919 return true;
920 }
921 @Override
922 public Boolean visitClassType(ClassType t, Void s) {
923 if (t.isUnion() || t.isIntersection()) {
924 return false;
925 }
926 for (Type targ : t.allparams()) {
927 if (!visit(targ, s)) {
928 return false;
929 }
930 }
931 return true;
932 }
933
934 @Override
935 public Boolean visitTypeVar(TypeVar t, Void s) {
936 /* Any type variable mentioned in the inferred type must have been declared as a type parameter
937 (i.e cannot have been produced by inference (18.4))
938 */
939 return (t.tsym.flags() & SYNTHETIC) == 0;
940 }
941
942 @Override
943 public Boolean visitCapturedType(CapturedType t, Void s) {
944 /* Any type variable mentioned in the inferred type must have been declared as a type parameter
945 (i.e cannot have been produced by capture conversion (5.1.10))
946 */
947 return false;
948 }
949
950 @Override
951 public Boolean visitArrayType(ArrayType t, Void s) {
952 return visit(t.elemtype, s);
953 }
954
955 @Override
956 public Boolean visitWildcardType(WildcardType t, Void s) {
957 return visit(t.type, s);
958 }
959 };
960
961 void checkVarargsMethodDecl(Env<AttrContext> env, JCMethodDecl tree) {
962 MethodSymbol m = tree.sym;
963 boolean hasTrustMeAnno = m.attribute(syms.trustMeType.tsym) != null;
964 Type varargElemType = null;
965 if (m.isVarArgs()) {
966 varargElemType = types.elemtype(tree.params.last().type);
967 }
968 if (hasTrustMeAnno && !isTrustMeAllowedOnMethod(m)) {
969 if (varargElemType != null) {
970 JCDiagnostic msg = Feature.PRIVATE_SAFE_VARARGS.allowedInSource(source) ?
971 diags.fragment(Fragments.VarargsTrustmeOnVirtualVarargs(m)) :
972 diags.fragment(Fragments.VarargsTrustmeOnVirtualVarargsFinalOnly(m));
973 log.error(tree,
974 Errors.VarargsInvalidTrustmeAnno(syms.trustMeType.tsym,
975 msg));
976 } else {
977 log.error(tree,
978 Errors.VarargsInvalidTrustmeAnno(syms.trustMeType.tsym,
979 Fragments.VarargsTrustmeOnNonVarargsMeth(m)));
980 }
981 } else if (hasTrustMeAnno && varargElemType != null &&
982 types.isReifiable(varargElemType)) {
983 warnUnsafeVararg(tree, Warnings.VarargsRedundantTrustmeAnno(
984 syms.trustMeType.tsym,
985 diags.fragment(Fragments.VarargsTrustmeOnReifiableVarargs(varargElemType))));
986 }
987 else if (!hasTrustMeAnno && varargElemType != null &&
988 !types.isReifiable(varargElemType)) {
989 warnUnchecked(tree.params.head.pos(), Warnings.UncheckedVarargsNonReifiableType(varargElemType));
990 }
991 }
992 //where
993 private boolean isTrustMeAllowedOnMethod(Symbol s) {
994 return (s.flags() & VARARGS) != 0 &&
995 (s.isConstructor() ||
996 (s.flags() & (STATIC | FINAL |
997 (Feature.PRIVATE_SAFE_VARARGS.allowedInSource(source) ? PRIVATE : 0) )) != 0);
998 }
999
1000 Type checkLocalVarType(DiagnosticPosition pos, Type t, Name name) {
1001 //check that resulting type is not the null type
1002 if (t.hasTag(BOT)) {
1003 log.error(pos, Errors.CantInferLocalVarType(name, Fragments.LocalCantInferNull));
1004 return types.createErrorType(t);
1005 } else if (t.hasTag(VOID)) {
1006 log.error(pos, Errors.CantInferLocalVarType(name, Fragments.LocalCantInferVoid));
1007 return types.createErrorType(t);
1008 }
1009
1010 //upward project the initializer type
1011 return types.upward(t, types.captures(t)).baseType();
1012 }
1013
1014 Type checkMethod(final Type mtype,
1015 final Symbol sym,
1016 final Env<AttrContext> env,
1017 final List<JCExpression> argtrees,
1018 final List<Type> argtypes,
1019 final boolean useVarargs,
1020 InferenceContext inferenceContext) {
1021 // System.out.println("call : " + env.tree);
1022 // System.out.println("method : " + owntype);
1023 // System.out.println("actuals: " + argtypes);
1024 if (inferenceContext.free(mtype)) {
1025 inferenceContext.addFreeTypeListener(List.of(mtype),
1026 solvedContext -> checkMethod(solvedContext.asInstType(mtype), sym, env, argtrees, argtypes, useVarargs, solvedContext));
1027 return mtype;
1028 }
1029 Type owntype = mtype;
1030 List<Type> formals = owntype.getParameterTypes();
1031 List<Type> nonInferred = sym.type.getParameterTypes();
1032 if (nonInferred.length() != formals.length()) nonInferred = formals;
1033 Type last = useVarargs ? formals.last() : null;
1034 if (sym.name == names.init && sym.owner == syms.enumSym) {
1035 formals = formals.tail.tail;
1036 nonInferred = nonInferred.tail.tail;
1037 }
1038 if ((sym.flags() & ANONCONSTR_BASED) != 0) {
1039 formals = formals.tail;
1040 nonInferred = nonInferred.tail;
1041 }
1042 List<JCExpression> args = argtrees;
1043 if (args != null) {
1044 //this is null when type-checking a method reference
1045 while (formals.head != last) {
1046 JCTree arg = args.head;
1047 Warner warn = convertWarner(arg.pos(), arg.type, nonInferred.head);
1048 assertConvertible(arg, arg.type, formals.head, warn);
1049 args = args.tail;
1050 formals = formals.tail;
1051 nonInferred = nonInferred.tail;
1052 }
1053 if (useVarargs) {
1054 Type varArg = types.elemtype(last);
1055 while (args.tail != null) {
1056 JCTree arg = args.head;
1057 Warner warn = convertWarner(arg.pos(), arg.type, varArg);
1058 assertConvertible(arg, arg.type, varArg, warn);
1059 args = args.tail;
1060 }
1061 } else if ((sym.flags() & (VARARGS | SIGNATURE_POLYMORPHIC)) == VARARGS) {
1062 // non-varargs call to varargs method
1063 Type varParam = owntype.getParameterTypes().last();
1064 Type lastArg = argtypes.last();
1065 if (types.isSubtypeUnchecked(lastArg, types.elemtype(varParam)) &&
1066 !types.isSameType(types.erasure(varParam), types.erasure(lastArg)))
1067 log.warning(argtrees.last().pos(),
1068 Warnings.InexactNonVarargsCall(types.elemtype(varParam),varParam));
1069 }
1070 }
1071 if (useVarargs) {
1072 Type argtype = owntype.getParameterTypes().last();
1073 if (!types.isReifiable(argtype) &&
1074 (sym.baseSymbol().attribute(syms.trustMeType.tsym) == null ||
1075 !isTrustMeAllowedOnMethod(sym))) {
1076 warnUnchecked(env.tree.pos(), Warnings.UncheckedGenericArrayCreation(argtype));
1077 }
1078 TreeInfo.setVarargsElement(env.tree, types.elemtype(argtype));
1079 }
1080 return owntype;
1081 }
1082 //where
1083 private void assertConvertible(JCTree tree, Type actual, Type formal, Warner warn) {
1084 if (types.isConvertible(actual, formal, warn))
1085 return;
1086
1087 if (formal.isCompound()
1088 && types.isSubtype(actual, types.supertype(formal))
1089 && types.isSubtypeUnchecked(actual, types.interfaces(formal), warn))
1090 return;
1091 }
1092
1093 /**
1094 * Check that type 't' is a valid instantiation of a generic class
1095 * (see JLS 4.5)
1096 *
1097 * @param t class type to be checked
1098 * @return true if 't' is well-formed
1099 */
1100 public boolean checkValidGenericType(Type t) {
1101 return firstIncompatibleTypeArg(t) == null;
1102 }
1103 //WHERE
1104 private Type firstIncompatibleTypeArg(Type type) {
1105 List<Type> formals = type.tsym.type.allparams();
1106 List<Type> actuals = type.allparams();
1107 List<Type> args = type.getTypeArguments();
1108 List<Type> forms = type.tsym.type.getTypeArguments();
1109 ListBuffer<Type> bounds_buf = new ListBuffer<>();
1110
1111 // For matching pairs of actual argument types `a' and
1112 // formal type parameters with declared bound `b' ...
1113 while (args.nonEmpty() && forms.nonEmpty()) {
1114 // exact type arguments needs to know their
1115 // bounds (for upper and lower bound
1116 // calculations). So we create new bounds where
1117 // type-parameters are replaced with actuals argument types.
1118 bounds_buf.append(types.subst(forms.head.getUpperBound(), formals, actuals));
1119 args = args.tail;
1120 forms = forms.tail;
1121 }
1122
1123 args = type.getTypeArguments();
1124 List<Type> tvars_cap = types.substBounds(formals,
1125 formals,
1126 types.capture(type).allparams());
1127 while (args.nonEmpty() && tvars_cap.nonEmpty()) {
1128 // Let the actual arguments know their bound
1129 args.head.withTypeVar((TypeVar)tvars_cap.head);
1130 args = args.tail;
1131 tvars_cap = tvars_cap.tail;
1132 }
1133
1134 args = type.getTypeArguments();
1135 List<Type> bounds = bounds_buf.toList();
1136
1137 while (args.nonEmpty() && bounds.nonEmpty()) {
1138 Type actual = args.head;
1139 if (!isTypeArgErroneous(actual) &&
1140 !bounds.head.isErroneous() &&
1141 !checkExtends(actual, bounds.head)) {
1142 return args.head;
1143 }
1144 args = args.tail;
1145 bounds = bounds.tail;
1146 }
1147
1148 args = type.getTypeArguments();
1149 bounds = bounds_buf.toList();
1150
1151 for (Type arg : types.capture(type).getTypeArguments()) {
1152 if (arg.hasTag(TYPEVAR) &&
1153 arg.getUpperBound().isErroneous() &&
1154 !bounds.head.isErroneous() &&
1155 !isTypeArgErroneous(args.head)) {
1156 return args.head;
1157 }
1158 bounds = bounds.tail;
1159 args = args.tail;
1160 }
1161
1162 return null;
1163 }
1164 //where
1165 boolean isTypeArgErroneous(Type t) {
1166 return isTypeArgErroneous.visit(t);
1167 }
1168
1169 Types.UnaryVisitor<Boolean> isTypeArgErroneous = new Types.UnaryVisitor<Boolean>() {
1170 public Boolean visitType(Type t, Void s) {
1171 return t.isErroneous();
1172 }
1173 @Override
1174 public Boolean visitTypeVar(TypeVar t, Void s) {
1175 return visit(t.getUpperBound());
1176 }
1177 @Override
1178 public Boolean visitCapturedType(CapturedType t, Void s) {
1179 return visit(t.getUpperBound()) ||
1180 visit(t.getLowerBound());
1181 }
1182 @Override
1183 public Boolean visitWildcardType(WildcardType t, Void s) {
1184 return visit(t.type);
1185 }
1186 };
1187
1188 /** Check that given modifiers are legal for given symbol and
1189 * return modifiers together with any implicit modifiers for that symbol.
1190 * Warning: we can't use flags() here since this method
1191 * is called during class enter, when flags() would cause a premature
1192 * completion.
1193 * @param pos Position to be used for error reporting.
1194 * @param flags The set of modifiers given in a definition.
1195 * @param sym The defined symbol.
1196 */
1197 long checkFlags(DiagnosticPosition pos, long flags, Symbol sym, JCTree tree) {
1198 long mask;
1199 long implicit = 0;
1200
1201 switch (sym.kind) {
1202 case VAR:
1203 if (TreeInfo.isReceiverParam(tree))
1204 mask = ReceiverParamFlags;
1205 else if (sym.owner.kind != TYP)
1206 mask = LocalVarFlags;
1207 else if ((sym.owner.flags_field & INTERFACE) != 0)
1208 mask = implicit = InterfaceVarFlags;
1209 else
1210 mask = VarFlags;
1211 break;
1212 case MTH:
1213 if (sym.name == names.init) {
1214 if ((sym.owner.flags_field & ENUM) != 0) {
1215 // enum constructors cannot be declared public or
1216 // protected and must be implicitly or explicitly
1217 // private
1218 implicit = PRIVATE;
1219 mask = PRIVATE;
1220 } else
1221 mask = ConstructorFlags;
1222 } else if ((sym.owner.flags_field & INTERFACE) != 0) {
1223 if ((sym.owner.flags_field & ANNOTATION) != 0) {
1224 mask = AnnotationTypeElementMask;
1225 implicit = PUBLIC | ABSTRACT;
1226 } else if ((flags & (DEFAULT | STATIC | PRIVATE)) != 0) {
1227 mask = InterfaceMethodMask;
1228 implicit = (flags & PRIVATE) != 0 ? 0 : PUBLIC;
1229 if ((flags & DEFAULT) != 0) {
1230 implicit |= ABSTRACT;
1231 }
1232 } else {
1233 mask = implicit = InterfaceMethodFlags;
1234 }
1235 } else if ((sym.owner.flags_field & RECORD) != 0) {
1236 mask = RecordMethodFlags;
1237 } else {
1238 mask = MethodFlags;
1239 }
1240 if ((flags & STRICTFP) != 0) {
1241 warnOnExplicitStrictfp(pos);
1242 }
1243 // Imply STRICTFP if owner has STRICTFP set.
1244 if (((flags|implicit) & Flags.ABSTRACT) == 0 ||
1245 ((flags) & Flags.DEFAULT) != 0)
1246 implicit |= sym.owner.flags_field & STRICTFP;
1247 break;
1248 case TYP:
1249 if (sym.owner.kind.matches(KindSelector.VAL_MTH) ||
1250 (sym.isDirectlyOrIndirectlyLocal() && (flags & ANNOTATION) != 0)) {
1251 boolean implicitlyStatic = !sym.isAnonymous() &&
1252 ((flags & RECORD) != 0 || (flags & ENUM) != 0 || (flags & INTERFACE) != 0);
1253 boolean staticOrImplicitlyStatic = (flags & STATIC) != 0 || implicitlyStatic;
1254 // local statics are allowed only if records are allowed too
1255 mask = staticOrImplicitlyStatic && allowRecords && (flags & ANNOTATION) == 0 ? StaticLocalFlags : LocalClassFlags;
1256 implicit = implicitlyStatic ? STATIC : implicit;
1257 } else if (sym.owner.kind == TYP) {
1258 // statics in inner classes are allowed only if records are allowed too
1259 mask = ((flags & STATIC) != 0) && allowRecords && (flags & ANNOTATION) == 0 ? ExtendedMemberStaticClassFlags : ExtendedMemberClassFlags;
1260 if (sym.owner.owner.kind == PCK ||
1261 (sym.owner.flags_field & STATIC) != 0) {
1262 mask |= STATIC;
1263 } else if (!allowRecords && ((flags & ENUM) != 0 || (flags & RECORD) != 0)) {
1264 log.error(pos, Errors.StaticDeclarationNotAllowedInInnerClasses);
1265 }
1266 // Nested interfaces and enums are always STATIC (Spec ???)
1267 if ((flags & (INTERFACE | ENUM | RECORD)) != 0 ) implicit = STATIC;
1268 } else {
1269 mask = ExtendedClassFlags;
1270 }
1271 // Interfaces are always ABSTRACT
1272 if ((flags & INTERFACE) != 0) implicit |= ABSTRACT;
1273
1274 if ((flags & ENUM) != 0) {
1275 // enums can't be declared abstract, final, sealed or non-sealed
1276 mask &= ~(ABSTRACT | FINAL | SEALED | NON_SEALED);
1277 implicit |= implicitEnumFinalFlag(tree);
1278 }
1279 if ((flags & RECORD) != 0) {
1280 // records can't be declared abstract
1281 mask &= ~ABSTRACT;
1282 implicit |= FINAL;
1283 }
1284 if ((flags & STRICTFP) != 0) {
1285 warnOnExplicitStrictfp(pos);
1286 }
1287 // Imply STRICTFP if owner has STRICTFP set.
1288 implicit |= sym.owner.flags_field & STRICTFP;
1289 break;
1290 default:
1291 throw new AssertionError();
1292 }
1293 long illegal = flags & ExtendedStandardFlags & ~mask;
1294 if (illegal != 0) {
1295 if ((illegal & INTERFACE) != 0) {
1296 log.error(pos, ((flags & ANNOTATION) != 0) ? Errors.AnnotationDeclNotAllowedHere : Errors.IntfNotAllowedHere);
1297 mask |= INTERFACE;
1298 }
1299 else {
1300 log.error(pos,
1301 Errors.ModNotAllowedHere(asFlagSet(illegal)));
1302 }
1303 }
1304 else if ((sym.kind == TYP ||
1305 // ISSUE: Disallowing abstract&private is no longer appropriate
1306 // in the presence of inner classes. Should it be deleted here?
1307 checkDisjoint(pos, flags,
1308 ABSTRACT,
1309 PRIVATE | STATIC | DEFAULT))
1310 &&
1311 checkDisjoint(pos, flags,
1312 STATIC | PRIVATE,
1313 DEFAULT)
1314 &&
1315 checkDisjoint(pos, flags,
1316 ABSTRACT | INTERFACE,
1317 FINAL | NATIVE | SYNCHRONIZED)
1318 &&
1319 checkDisjoint(pos, flags,
1320 PUBLIC,
1321 PRIVATE | PROTECTED)
1322 &&
1323 checkDisjoint(pos, flags,
1324 PRIVATE,
1325 PUBLIC | PROTECTED)
1326 &&
1327 checkDisjoint(pos, flags,
1328 FINAL,
1329 VOLATILE)
1330 &&
1331 (sym.kind == TYP ||
1332 checkDisjoint(pos, flags,
1333 ABSTRACT | NATIVE,
1334 STRICTFP))
1335 && checkDisjoint(pos, flags,
1336 FINAL,
1337 SEALED | NON_SEALED)
1338 && checkDisjoint(pos, flags,
1339 SEALED,
1340 FINAL | NON_SEALED)
1341 && checkDisjoint(pos, flags,
1342 SEALED,
1343 ANNOTATION)) {
1344 // skip
1345 }
1346 return flags & (mask | ~ExtendedStandardFlags) | implicit;
1347 }
1348
1349 private void warnOnExplicitStrictfp(DiagnosticPosition pos) {
1350 DiagnosticPosition prevLintPos = deferredLintHandler.setPos(pos);
1351 try {
1352 deferredLintHandler.report(() -> {
1353 if (lint.isEnabled(LintCategory.STRICTFP)) {
1354 log.warning(LintCategory.STRICTFP,
1355 pos, Warnings.Strictfp); }
1356 });
1357 } finally {
1358 deferredLintHandler.setPos(prevLintPos);
1359 }
1360 }
1361
1362
1363 /** Determine if this enum should be implicitly final.
1364 *
1365 * If the enum has no specialized enum constants, it is final.
1366 *
1367 * If the enum does have specialized enum constants, it is
1368 * <i>not</i> final.
1369 */
1370 private long implicitEnumFinalFlag(JCTree tree) {
1371 if (!tree.hasTag(CLASSDEF)) return 0;
1372 class SpecialTreeVisitor extends JCTree.Visitor {
1373 boolean specialized;
1374 SpecialTreeVisitor() {
1375 this.specialized = false;
1376 }
1377
1378 @Override
1379 public void visitTree(JCTree tree) { /* no-op */ }
1380
1381 @Override
1382 public void visitVarDef(JCVariableDecl tree) {
1383 if ((tree.mods.flags & ENUM) != 0) {
1384 if (tree.init instanceof JCNewClass newClass && newClass.def != null) {
1385 specialized = true;
1386 }
1387 }
1388 }
1389 }
1390
1391 SpecialTreeVisitor sts = new SpecialTreeVisitor();
1392 JCClassDecl cdef = (JCClassDecl) tree;
1393 for (JCTree defs: cdef.defs) {
1394 defs.accept(sts);
1395 if (sts.specialized) return allowSealed ? SEALED : 0;
1396 }
1397 return FINAL;
1398 }
1399
1400 /* *************************************************************************
1401 * Type Validation
1402 **************************************************************************/
1403
1404 /** Validate a type expression. That is,
1405 * check that all type arguments of a parametric type are within
1406 * their bounds. This must be done in a second phase after type attribution
1407 * since a class might have a subclass as type parameter bound. E.g:
1408 *
1409 * <pre>{@code
1410 * class B<A extends C> { ... }
1411 * class C extends B<C> { ... }
1412 * }</pre>
1413 *
1414 * and we can't make sure that the bound is already attributed because
1415 * of possible cycles.
1416 *
1417 * Visitor method: Validate a type expression, if it is not null, catching
1418 * and reporting any completion failures.
1419 */
1420 void validate(JCTree tree, Env<AttrContext> env) {
1421 validate(tree, env, true);
1422 }
1423 void validate(JCTree tree, Env<AttrContext> env, boolean checkRaw) {
1424 new Validator(env).validateTree(tree, checkRaw, true);
1425 }
1426
1427 /** Visitor method: Validate a list of type expressions.
1428 */
1429 void validate(List<? extends JCTree> trees, Env<AttrContext> env) {
1430 for (List<? extends JCTree> l = trees; l.nonEmpty(); l = l.tail)
1431 validate(l.head, env);
1432 }
1433
1434 /** A visitor class for type validation.
1435 */
1436 class Validator extends JCTree.Visitor {
1437
1438 boolean checkRaw;
1439 boolean isOuter;
1440 Env<AttrContext> env;
1441
1442 Validator(Env<AttrContext> env) {
1443 this.env = env;
1444 }
1445
1446 @Override
1447 public void visitTypeArray(JCArrayTypeTree tree) {
1448 validateTree(tree.elemtype, checkRaw, isOuter);
1449 }
1450
1451 @Override
1452 public void visitTypeApply(JCTypeApply tree) {
1453 if (tree.type.hasTag(CLASS)) {
1454 List<JCExpression> args = tree.arguments;
1455 List<Type> forms = tree.type.tsym.type.getTypeArguments();
1456
1457 Type incompatibleArg = firstIncompatibleTypeArg(tree.type);
1458 if (incompatibleArg != null) {
1459 for (JCTree arg : tree.arguments) {
1460 if (arg.type == incompatibleArg) {
1461 log.error(arg, Errors.NotWithinBounds(incompatibleArg, forms.head));
1462 }
1463 forms = forms.tail;
1464 }
1465 }
1466
1467 forms = tree.type.tsym.type.getTypeArguments();
1468
1469 boolean is_java_lang_Class = tree.type.tsym.flatName() == names.java_lang_Class;
1470
1471 // For matching pairs of actual argument types `a' and
1472 // formal type parameters with declared bound `b' ...
1473 while (args.nonEmpty() && forms.nonEmpty()) {
1474 validateTree(args.head,
1475 !(isOuter && is_java_lang_Class),
1476 false);
1477 args = args.tail;
1478 forms = forms.tail;
1479 }
1480
1481 // Check that this type is either fully parameterized, or
1482 // not parameterized at all.
1483 if (tree.type.getEnclosingType().isRaw())
1484 log.error(tree.pos(), Errors.ImproperlyFormedTypeInnerRawParam);
1485 if (tree.clazz.hasTag(SELECT))
1486 visitSelectInternal((JCFieldAccess)tree.clazz);
1487 }
1488 }
1489
1490 @Override
1491 public void visitTypeParameter(JCTypeParameter tree) {
1492 validateTrees(tree.bounds, true, isOuter);
1493 checkClassBounds(tree.pos(), tree.type);
1494 }
1495
1496 @Override
1497 public void visitWildcard(JCWildcard tree) {
1498 if (tree.inner != null)
1499 validateTree(tree.inner, true, isOuter);
1500 }
1501
1502 @Override
1503 public void visitSelect(JCFieldAccess tree) {
1504 if (tree.type.hasTag(CLASS)) {
1505 visitSelectInternal(tree);
1506
1507 // Check that this type is either fully parameterized, or
1508 // not parameterized at all.
1509 if (tree.selected.type.isParameterized() && tree.type.tsym.type.getTypeArguments().nonEmpty())
1510 log.error(tree.pos(), Errors.ImproperlyFormedTypeParamMissing);
1511 }
1512 }
1513
1514 public void visitSelectInternal(JCFieldAccess tree) {
1515 if (tree.type.tsym.isStatic() &&
1516 tree.selected.type.isParameterized()) {
1517 // The enclosing type is not a class, so we are
1518 // looking at a static member type. However, the
1519 // qualifying expression is parameterized.
1520 log.error(tree.pos(), Errors.CantSelectStaticClassFromParamType);
1521 } else {
1522 // otherwise validate the rest of the expression
1523 tree.selected.accept(this);
1524 }
1525 }
1526
1527 @Override
1528 public void visitAnnotatedType(JCAnnotatedType tree) {
1529 tree.underlyingType.accept(this);
1530 }
1531
1532 @Override
1533 public void visitTypeIdent(JCPrimitiveTypeTree that) {
1534 if (that.type.hasTag(TypeTag.VOID)) {
1535 log.error(that.pos(), Errors.VoidNotAllowedHere);
1536 }
1537 super.visitTypeIdent(that);
1538 }
1539
1540 /** Default visitor method: do nothing.
1541 */
1542 @Override
1543 public void visitTree(JCTree tree) {
1544 }
1545
1546 public void validateTree(JCTree tree, boolean checkRaw, boolean isOuter) {
1547 if (tree != null) {
1548 boolean prevCheckRaw = this.checkRaw;
1549 this.checkRaw = checkRaw;
1550 this.isOuter = isOuter;
1551
1552 try {
1553 tree.accept(this);
1554 if (checkRaw)
1555 checkRaw(tree, env);
1556 } catch (CompletionFailure ex) {
1557 completionError(tree.pos(), ex);
1558 } finally {
1559 this.checkRaw = prevCheckRaw;
1560 }
1561 }
1562 }
1563
1564 public void validateTrees(List<? extends JCTree> trees, boolean checkRaw, boolean isOuter) {
1565 for (List<? extends JCTree> l = trees; l.nonEmpty(); l = l.tail)
1566 validateTree(l.head, checkRaw, isOuter);
1567 }
1568 }
1569
1570 void checkRaw(JCTree tree, Env<AttrContext> env) {
1571 if (lint.isEnabled(LintCategory.RAW) &&
1572 tree.type.hasTag(CLASS) &&
1573 !TreeInfo.isDiamond(tree) &&
1574 !withinAnonConstr(env) &&
1575 tree.type.isRaw()) {
1576 log.warning(LintCategory.RAW,
1577 tree.pos(), Warnings.RawClassUse(tree.type, tree.type.tsym.type));
1578 }
1579 }
1580 //where
1581 private boolean withinAnonConstr(Env<AttrContext> env) {
1582 return env.enclClass.name.isEmpty() &&
1583 env.enclMethod != null && env.enclMethod.name == names.init;
1584 }
1585
1586 /* *************************************************************************
1587 * Exception checking
1588 **************************************************************************/
1589
1590 /* The following methods treat classes as sets that contain
1591 * the class itself and all their subclasses
1592 */
1593
1594 /** Is given type a subtype of some of the types in given list?
1595 */
1596 boolean subset(Type t, List<Type> ts) {
1597 for (List<Type> l = ts; l.nonEmpty(); l = l.tail)
1598 if (types.isSubtype(t, l.head)) return true;
1599 return false;
1600 }
1601
1602 /** Is given type a subtype or supertype of
1603 * some of the types in given list?
1604 */
1605 boolean intersects(Type t, List<Type> ts) {
1606 for (List<Type> l = ts; l.nonEmpty(); l = l.tail)
1607 if (types.isSubtype(t, l.head) || types.isSubtype(l.head, t)) return true;
1608 return false;
1609 }
1610
1611 /** Add type set to given type list, unless it is a subclass of some class
1612 * in the list.
1613 */
1614 List<Type> incl(Type t, List<Type> ts) {
1615 return subset(t, ts) ? ts : excl(t, ts).prepend(t);
1616 }
1617
1618 /** Remove type set from type set list.
1619 */
1620 List<Type> excl(Type t, List<Type> ts) {
1621 if (ts.isEmpty()) {
1622 return ts;
1623 } else {
1624 List<Type> ts1 = excl(t, ts.tail);
1625 if (types.isSubtype(ts.head, t)) return ts1;
1626 else if (ts1 == ts.tail) return ts;
1627 else return ts1.prepend(ts.head);
1628 }
1629 }
1630
1631 /** Form the union of two type set lists.
1632 */
1633 List<Type> union(List<Type> ts1, List<Type> ts2) {
1634 List<Type> ts = ts1;
1635 for (List<Type> l = ts2; l.nonEmpty(); l = l.tail)
1636 ts = incl(l.head, ts);
1637 return ts;
1638 }
1639
1640 /** Form the difference of two type lists.
1641 */
1642 List<Type> diff(List<Type> ts1, List<Type> ts2) {
1643 List<Type> ts = ts1;
1644 for (List<Type> l = ts2; l.nonEmpty(); l = l.tail)
1645 ts = excl(l.head, ts);
1646 return ts;
1647 }
1648
1649 /** Form the intersection of two type lists.
1650 */
1651 public List<Type> intersect(List<Type> ts1, List<Type> ts2) {
1652 List<Type> ts = List.nil();
1653 for (List<Type> l = ts1; l.nonEmpty(); l = l.tail)
1654 if (subset(l.head, ts2)) ts = incl(l.head, ts);
1655 for (List<Type> l = ts2; l.nonEmpty(); l = l.tail)
1656 if (subset(l.head, ts1)) ts = incl(l.head, ts);
1657 return ts;
1658 }
1659
1660 /** Is exc an exception symbol that need not be declared?
1661 */
1662 boolean isUnchecked(ClassSymbol exc) {
1663 return
1664 exc.kind == ERR ||
1665 exc.isSubClass(syms.errorType.tsym, types) ||
1666 exc.isSubClass(syms.runtimeExceptionType.tsym, types);
1667 }
1668
1669 /** Is exc an exception type that need not be declared?
1670 */
1671 boolean isUnchecked(Type exc) {
1672 return
1673 (exc.hasTag(TYPEVAR)) ? isUnchecked(types.supertype(exc)) :
1674 (exc.hasTag(CLASS)) ? isUnchecked((ClassSymbol)exc.tsym) :
1675 exc.hasTag(BOT);
1676 }
1677
1678 boolean isChecked(Type exc) {
1679 return !isUnchecked(exc);
1680 }
1681
1682 /** Same, but handling completion failures.
1683 */
1684 boolean isUnchecked(DiagnosticPosition pos, Type exc) {
1685 try {
1686 return isUnchecked(exc);
1687 } catch (CompletionFailure ex) {
1688 completionError(pos, ex);
1689 return true;
1690 }
1691 }
1692
1693 /** Is exc handled by given exception list?
1694 */
1695 boolean isHandled(Type exc, List<Type> handled) {
1696 return isUnchecked(exc) || subset(exc, handled);
1697 }
1698
1699 /** Return all exceptions in thrown list that are not in handled list.
1700 * @param thrown The list of thrown exceptions.
1701 * @param handled The list of handled exceptions.
1702 */
1703 List<Type> unhandled(List<Type> thrown, List<Type> handled) {
1704 List<Type> unhandled = List.nil();
1705 for (List<Type> l = thrown; l.nonEmpty(); l = l.tail)
1706 if (!isHandled(l.head, handled)) unhandled = unhandled.prepend(l.head);
1707 return unhandled;
1708 }
1709
1710 /* *************************************************************************
1711 * Overriding/Implementation checking
1712 **************************************************************************/
1713
1714 /** The level of access protection given by a flag set,
1715 * where PRIVATE is highest and PUBLIC is lowest.
1716 */
1717 static int protection(long flags) {
1718 switch ((short)(flags & AccessFlags)) {
1719 case PRIVATE: return 3;
1720 case PROTECTED: return 1;
1721 default:
1722 case PUBLIC: return 0;
1723 case 0: return 2;
1724 }
1725 }
1726
1727 /** A customized "cannot override" error message.
1728 * @param m The overriding method.
1729 * @param other The overridden method.
1730 * @return An internationalized string.
1731 */
1732 Fragment cannotOverride(MethodSymbol m, MethodSymbol other) {
1733 Symbol mloc = m.location();
1734 Symbol oloc = other.location();
1735
1736 if ((other.owner.flags() & INTERFACE) == 0)
1737 return Fragments.CantOverride(m, mloc, other, oloc);
1738 else if ((m.owner.flags() & INTERFACE) == 0)
1739 return Fragments.CantImplement(m, mloc, other, oloc);
1740 else
1741 return Fragments.ClashesWith(m, mloc, other, oloc);
1742 }
1743
1744 /** A customized "override" warning message.
1745 * @param m The overriding method.
1746 * @param other The overridden method.
1747 * @return An internationalized string.
1748 */
1749 Fragment uncheckedOverrides(MethodSymbol m, MethodSymbol other) {
1750 Symbol mloc = m.location();
1751 Symbol oloc = other.location();
1752
1753 if ((other.owner.flags() & INTERFACE) == 0)
1754 return Fragments.UncheckedOverride(m, mloc, other, oloc);
1755 else if ((m.owner.flags() & INTERFACE) == 0)
1756 return Fragments.UncheckedImplement(m, mloc, other, oloc);
1757 else
1758 return Fragments.UncheckedClashWith(m, mloc, other, oloc);
1759 }
1760
1761 /** A customized "override" warning message.
1762 * @param m The overriding method.
1763 * @param other The overridden method.
1764 * @return An internationalized string.
1765 */
1766 Fragment varargsOverrides(MethodSymbol m, MethodSymbol other) {
1767 Symbol mloc = m.location();
1768 Symbol oloc = other.location();
1769
1770 if ((other.owner.flags() & INTERFACE) == 0)
1771 return Fragments.VarargsOverride(m, mloc, other, oloc);
1772 else if ((m.owner.flags() & INTERFACE) == 0)
1773 return Fragments.VarargsImplement(m, mloc, other, oloc);
1774 else
1775 return Fragments.VarargsClashWith(m, mloc, other, oloc);
1776 }
1777
1778 /** Check that this method conforms with overridden method 'other'.
1779 * where `origin' is the class where checking started.
1780 * Complications:
1781 * (1) Do not check overriding of synthetic methods
1782 * (reason: they might be final).
1783 * todo: check whether this is still necessary.
1784 * (2) Admit the case where an interface proxy throws fewer exceptions
1785 * than the method it implements. Augment the proxy methods with the
1786 * undeclared exceptions in this case.
1787 * (3) When generics are enabled, admit the case where an interface proxy
1788 * has a result type
1789 * extended by the result type of the method it implements.
1790 * Change the proxies result type to the smaller type in this case.
1791 *
1792 * @param tree The tree from which positions
1793 * are extracted for errors.
1794 * @param m The overriding method.
1795 * @param other The overridden method.
1796 * @param origin The class of which the overriding method
1797 * is a member.
1798 */
1799 void checkOverride(JCTree tree,
1800 MethodSymbol m,
1801 MethodSymbol other,
1802 ClassSymbol origin) {
1803 // Don't check overriding of synthetic methods or by bridge methods.
1804 if ((m.flags() & (SYNTHETIC|BRIDGE)) != 0 || (other.flags() & SYNTHETIC) != 0) {
1805 return;
1806 }
1807
1808 // Error if static method overrides instance method (JLS 8.4.8.2).
1809 if ((m.flags() & STATIC) != 0 &&
1810 (other.flags() & STATIC) == 0) {
1811 log.error(TreeInfo.diagnosticPositionFor(m, tree),
1812 Errors.OverrideStatic(cannotOverride(m, other)));
1813 m.flags_field |= BAD_OVERRIDE;
1814 return;
1815 }
1816
1817 // Error if instance method overrides static or final
1818 // method (JLS 8.4.8.1).
1819 if ((other.flags() & FINAL) != 0 ||
1820 (m.flags() & STATIC) == 0 &&
1821 (other.flags() & STATIC) != 0) {
1822 log.error(TreeInfo.diagnosticPositionFor(m, tree),
1823 Errors.OverrideMeth(cannotOverride(m, other),
1824 asFlagSet(other.flags() & (FINAL | STATIC))));
1825 m.flags_field |= BAD_OVERRIDE;
1826 return;
1827 }
1828
1829 if ((m.owner.flags() & ANNOTATION) != 0) {
1830 // handled in validateAnnotationMethod
1831 return;
1832 }
1833
1834 // Error if overriding method has weaker access (JLS 8.4.8.3).
1835 if (protection(m.flags()) > protection(other.flags())) {
1836 log.error(TreeInfo.diagnosticPositionFor(m, tree),
1837 (other.flags() & AccessFlags) == 0 ?
1838 Errors.OverrideWeakerAccess(cannotOverride(m, other),
1839 "package") :
1840 Errors.OverrideWeakerAccess(cannotOverride(m, other),
1841 asFlagSet(other.flags() & AccessFlags)));
1842 m.flags_field |= BAD_OVERRIDE;
1843 return;
1844 }
1845
1846 if (shouldCheckPreview(m, other, origin)) {
1847 checkPreview(tree.pos(), m, other);
1848 }
1849
1850 Type mt = types.memberType(origin.type, m);
1851 Type ot = types.memberType(origin.type, other);
1852 // Error if overriding result type is different
1853 // (or, in the case of generics mode, not a subtype) of
1854 // overridden result type. We have to rename any type parameters
1855 // before comparing types.
1856 List<Type> mtvars = mt.getTypeArguments();
1857 List<Type> otvars = ot.getTypeArguments();
1858 Type mtres = mt.getReturnType();
1859 Type otres = types.subst(ot.getReturnType(), otvars, mtvars);
1860
1861 overrideWarner.clear();
1862 boolean resultTypesOK =
1863 types.returnTypeSubstitutable(mt, ot, otres, overrideWarner);
1864 if (!resultTypesOK) {
1865 if ((m.flags() & STATIC) != 0 && (other.flags() & STATIC) != 0) {
1866 log.error(TreeInfo.diagnosticPositionFor(m, tree),
1867 Errors.OverrideIncompatibleRet(Fragments.CantHide(m, m.location(), other,
1868 other.location()), mtres, otres));
1869 m.flags_field |= BAD_OVERRIDE;
1870 } else {
1871 log.error(TreeInfo.diagnosticPositionFor(m, tree),
1872 Errors.OverrideIncompatibleRet(cannotOverride(m, other), mtres, otres));
1873 m.flags_field |= BAD_OVERRIDE;
1874 }
1875 return;
1876 } else if (overrideWarner.hasNonSilentLint(LintCategory.UNCHECKED)) {
1877 warnUnchecked(TreeInfo.diagnosticPositionFor(m, tree),
1878 Warnings.OverrideUncheckedRet(uncheckedOverrides(m, other), mtres, otres));
1879 }
1880
1881 // Error if overriding method throws an exception not reported
1882 // by overridden method.
1883 List<Type> otthrown = types.subst(ot.getThrownTypes(), otvars, mtvars);
1884 List<Type> unhandledErased = unhandled(mt.getThrownTypes(), types.erasure(otthrown));
1885 List<Type> unhandledUnerased = unhandled(mt.getThrownTypes(), otthrown);
1886 if (unhandledErased.nonEmpty()) {
1887 log.error(TreeInfo.diagnosticPositionFor(m, tree),
1888 Errors.OverrideMethDoesntThrow(cannotOverride(m, other), unhandledUnerased.head));
1889 m.flags_field |= BAD_OVERRIDE;
1890 return;
1891 }
1892 else if (unhandledUnerased.nonEmpty()) {
1893 warnUnchecked(TreeInfo.diagnosticPositionFor(m, tree),
1894 Warnings.OverrideUncheckedThrown(cannotOverride(m, other), unhandledUnerased.head));
1895 return;
1896 }
1897
1898 // Optional warning if varargs don't agree
1899 if ((((m.flags() ^ other.flags()) & Flags.VARARGS) != 0)
1900 && lint.isEnabled(LintCategory.OVERRIDES)) {
1901 log.warning(TreeInfo.diagnosticPositionFor(m, tree),
1902 ((m.flags() & Flags.VARARGS) != 0)
1903 ? Warnings.OverrideVarargsMissing(varargsOverrides(m, other))
1904 : Warnings.OverrideVarargsExtra(varargsOverrides(m, other)));
1905 }
1906
1907 // Warn if instance method overrides bridge method (compiler spec ??)
1908 if ((other.flags() & BRIDGE) != 0) {
1909 log.warning(TreeInfo.diagnosticPositionFor(m, tree),
1910 Warnings.OverrideBridge(uncheckedOverrides(m, other)));
1911 }
1912
1913 // Warn if a deprecated method overridden by a non-deprecated one.
1914 if (!isDeprecatedOverrideIgnorable(other, origin)) {
1915 Lint prevLint = setLint(lint.augment(m));
1916 try {
1917 checkDeprecated(() -> TreeInfo.diagnosticPositionFor(m, tree), m, other);
1918 } finally {
1919 setLint(prevLint);
1920 }
1921 }
1922 }
1923 // where
1924 private boolean shouldCheckPreview(MethodSymbol m, MethodSymbol other, ClassSymbol origin) {
1925 if (m.owner != origin ||
1926 //performance - only do the expensive checks when the overridden method is a Preview API:
1927 (other.flags() & PREVIEW_API) == 0) {
1928 return false;
1929 }
1930
1931 for (Symbol s : types.membersClosure(origin.type, false).getSymbolsByName(m.name)) {
1932 if (m != s && m.overrides(s, origin, types, false)) {
1933 //only produce preview warnings or errors if "m" immediatelly overrides "other"
1934 //without intermediate overriding methods:
1935 return s == other;
1936 }
1937 }
1938
1939 return false;
1940 }
1941 private boolean isDeprecatedOverrideIgnorable(MethodSymbol m, ClassSymbol origin) {
1942 // If the method, m, is defined in an interface, then ignore the issue if the method
1943 // is only inherited via a supertype and also implemented in the supertype,
1944 // because in that case, we will rediscover the issue when examining the method
1945 // in the supertype.
1946 // If the method, m, is not defined in an interface, then the only time we need to
1947 // address the issue is when the method is the supertype implementation: any other
1948 // case, we will have dealt with when examining the supertype classes
1949 ClassSymbol mc = m.enclClass();
1950 Type st = types.supertype(origin.type);
1951 if (!st.hasTag(CLASS))
1952 return true;
1953 MethodSymbol stimpl = m.implementation((ClassSymbol)st.tsym, types, false);
1954
1955 if (mc != null && ((mc.flags() & INTERFACE) != 0)) {
1956 List<Type> intfs = types.interfaces(origin.type);
1957 return (intfs.contains(mc.type) ? false : (stimpl != null));
1958 }
1959 else
1960 return (stimpl != m);
1961 }
1962
1963
1964 // used to check if there were any unchecked conversions
1965 Warner overrideWarner = new Warner();
1966
1967 /** Check that a class does not inherit two concrete methods
1968 * with the same signature.
1969 * @param pos Position to be used for error reporting.
1970 * @param site The class type to be checked.
1971 */
1972 public void checkCompatibleConcretes(DiagnosticPosition pos, Type site) {
1973 Type sup = types.supertype(site);
1974 if (!sup.hasTag(CLASS)) return;
1975
1976 for (Type t1 = sup;
1977 t1.hasTag(CLASS) && t1.tsym.type.isParameterized();
1978 t1 = types.supertype(t1)) {
1979 for (Symbol s1 : t1.tsym.members().getSymbols(NON_RECURSIVE)) {
1980 if (s1.kind != MTH ||
1981 (s1.flags() & (STATIC|SYNTHETIC|BRIDGE)) != 0 ||
1982 !s1.isInheritedIn(site.tsym, types) ||
1983 ((MethodSymbol)s1).implementation(site.tsym,
1984 types,
1985 true) != s1)
1986 continue;
1987 Type st1 = types.memberType(t1, s1);
1988 int s1ArgsLength = st1.getParameterTypes().length();
1989 if (st1 == s1.type) continue;
1990
1991 for (Type t2 = sup;
1992 t2.hasTag(CLASS);
1993 t2 = types.supertype(t2)) {
1994 for (Symbol s2 : t2.tsym.members().getSymbolsByName(s1.name)) {
1995 if (s2 == s1 ||
1996 s2.kind != MTH ||
1997 (s2.flags() & (STATIC|SYNTHETIC|BRIDGE)) != 0 ||
1998 s2.type.getParameterTypes().length() != s1ArgsLength ||
1999 !s2.isInheritedIn(site.tsym, types) ||
2000 ((MethodSymbol)s2).implementation(site.tsym,
2001 types,
2002 true) != s2)
2003 continue;
2004 Type st2 = types.memberType(t2, s2);
2005 if (types.overrideEquivalent(st1, st2))
2006 log.error(pos,
2007 Errors.ConcreteInheritanceConflict(s1, t1, s2, t2, sup));
2008 }
2009 }
2010 }
2011 }
2012 }
2013
2014 /** Check that classes (or interfaces) do not each define an abstract
2015 * method with same name and arguments but incompatible return types.
2016 * @param pos Position to be used for error reporting.
2017 * @param t1 The first argument type.
2018 * @param t2 The second argument type.
2019 */
2020 public boolean checkCompatibleAbstracts(DiagnosticPosition pos,
2021 Type t1,
2022 Type t2,
2023 Type site) {
2024 if ((site.tsym.flags() & COMPOUND) != 0) {
2025 // special case for intersections: need to eliminate wildcards in supertypes
2026 t1 = types.capture(t1);
2027 t2 = types.capture(t2);
2028 }
2029 return firstIncompatibility(pos, t1, t2, site) == null;
2030 }
2031
2032 /** Return the first method which is defined with same args
2033 * but different return types in two given interfaces, or null if none
2034 * exists.
2035 * @param t1 The first type.
2036 * @param t2 The second type.
2037 * @param site The most derived type.
2038 * @return symbol from t2 that conflicts with one in t1.
2039 */
2040 private Symbol firstIncompatibility(DiagnosticPosition pos, Type t1, Type t2, Type site) {
2041 Map<TypeSymbol,Type> interfaces1 = new HashMap<>();
2042 closure(t1, interfaces1);
2043 Map<TypeSymbol,Type> interfaces2;
2044 if (t1 == t2)
2045 interfaces2 = interfaces1;
2046 else
2047 closure(t2, interfaces1, interfaces2 = new HashMap<>());
2048
2049 for (Type t3 : interfaces1.values()) {
2050 for (Type t4 : interfaces2.values()) {
2051 Symbol s = firstDirectIncompatibility(pos, t3, t4, site);
2052 if (s != null) return s;
2053 }
2054 }
2055 return null;
2056 }
2057
2058 /** Compute all the supertypes of t, indexed by type symbol. */
2059 private void closure(Type t, Map<TypeSymbol,Type> typeMap) {
2060 if (!t.hasTag(CLASS)) return;
2061 if (typeMap.put(t.tsym, t) == null) {
2062 closure(types.supertype(t), typeMap);
2063 for (Type i : types.interfaces(t))
2064 closure(i, typeMap);
2065 }
2066 }
2067
2068 /** Compute all the supertypes of t, indexed by type symbol (except those in typesSkip). */
2069 private void closure(Type t, Map<TypeSymbol,Type> typesSkip, Map<TypeSymbol,Type> typeMap) {
2070 if (!t.hasTag(CLASS)) return;
2071 if (typesSkip.get(t.tsym) != null) return;
2072 if (typeMap.put(t.tsym, t) == null) {
2073 closure(types.supertype(t), typesSkip, typeMap);
2074 for (Type i : types.interfaces(t))
2075 closure(i, typesSkip, typeMap);
2076 }
2077 }
2078
2079 /** Return the first method in t2 that conflicts with a method from t1. */
2080 private Symbol firstDirectIncompatibility(DiagnosticPosition pos, Type t1, Type t2, Type site) {
2081 for (Symbol s1 : t1.tsym.members().getSymbols(NON_RECURSIVE)) {
2082 Type st1 = null;
2083 if (s1.kind != MTH || !s1.isInheritedIn(site.tsym, types) ||
2084 (s1.flags() & SYNTHETIC) != 0) continue;
2085 Symbol impl = ((MethodSymbol)s1).implementation(site.tsym, types, false);
2086 if (impl != null && (impl.flags() & ABSTRACT) == 0) continue;
2087 for (Symbol s2 : t2.tsym.members().getSymbolsByName(s1.name)) {
2088 if (s1 == s2) continue;
2089 if (s2.kind != MTH || !s2.isInheritedIn(site.tsym, types) ||
2090 (s2.flags() & SYNTHETIC) != 0) continue;
2091 if (st1 == null) st1 = types.memberType(t1, s1);
2092 Type st2 = types.memberType(t2, s2);
2093 if (types.overrideEquivalent(st1, st2)) {
2094 List<Type> tvars1 = st1.getTypeArguments();
2095 List<Type> tvars2 = st2.getTypeArguments();
2096 Type rt1 = st1.getReturnType();
2097 Type rt2 = types.subst(st2.getReturnType(), tvars2, tvars1);
2098 boolean compat =
2099 types.isSameType(rt1, rt2) ||
2100 !rt1.isPrimitiveOrVoid() &&
2101 !rt2.isPrimitiveOrVoid() &&
2102 (types.covariantReturnType(rt1, rt2, types.noWarnings) ||
2103 types.covariantReturnType(rt2, rt1, types.noWarnings)) ||
2104 checkCommonOverriderIn(s1,s2,site);
2105 if (!compat) {
2106 if (types.isSameType(t1, t2)) {
2107 log.error(pos, Errors.IncompatibleDiffRetSameType(t1,
2108 s2.name, types.memberType(t2, s2).getParameterTypes()));
2109 } else {
2110 log.error(pos, Errors.TypesIncompatible(t1, t2,
2111 Fragments.IncompatibleDiffRet(s2.name, types.memberType(t2, s2).getParameterTypes())));
2112 }
2113 return s2;
2114 }
2115 } else if (checkNameClash((ClassSymbol)site.tsym, s1, s2) &&
2116 !checkCommonOverriderIn(s1, s2, site)) {
2117 log.error(pos, Errors.NameClashSameErasureNoOverride(
2118 s1.name, types.memberType(site, s1).asMethodType().getParameterTypes(), s1.location(),
2119 s2.name, types.memberType(site, s2).asMethodType().getParameterTypes(), s2.location()));
2120 return s2;
2121 }
2122 }
2123 }
2124 return null;
2125 }
2126 //WHERE
2127 boolean checkCommonOverriderIn(Symbol s1, Symbol s2, Type site) {
2128 Map<TypeSymbol,Type> supertypes = new HashMap<>();
2129 Type st1 = types.memberType(site, s1);
2130 Type st2 = types.memberType(site, s2);
2131 closure(site, supertypes);
2132 for (Type t : supertypes.values()) {
2133 for (Symbol s3 : t.tsym.members().getSymbolsByName(s1.name)) {
2134 if (s3 == s1 || s3 == s2 || s3.kind != MTH || (s3.flags() & (BRIDGE|SYNTHETIC)) != 0) continue;
2135 Type st3 = types.memberType(site,s3);
2136 if (types.overrideEquivalent(st3, st1) &&
2137 types.overrideEquivalent(st3, st2) &&
2138 types.returnTypeSubstitutable(st3, st1) &&
2139 types.returnTypeSubstitutable(st3, st2)) {
2140 return true;
2141 }
2142 }
2143 }
2144 return false;
2145 }
2146
2147 /** Check that a given method conforms with any method it overrides.
2148 * @param tree The tree from which positions are extracted
2149 * for errors.
2150 * @param m The overriding method.
2151 */
2152 void checkOverride(Env<AttrContext> env, JCMethodDecl tree, MethodSymbol m) {
2153 ClassSymbol origin = (ClassSymbol)m.owner;
2154 if ((origin.flags() & ENUM) != 0 && names.finalize.equals(m.name)) {
2155 if (m.overrides(syms.enumFinalFinalize, origin, types, false)) {
2156 log.error(tree.pos(), Errors.EnumNoFinalize);
2157 return;
2158 }
2159 }
2160 if (allowRecords && origin.isRecord()) {
2161 // let's find out if this is a user defined accessor in which case the @Override annotation is acceptable
2162 Optional<? extends RecordComponent> recordComponent = origin.getRecordComponents().stream()
2163 .filter(rc -> rc.accessor == tree.sym && (rc.accessor.flags_field & GENERATED_MEMBER) == 0).findFirst();
2164 if (recordComponent.isPresent()) {
2165 return;
2166 }
2167 }
2168
2169 for (Type t = origin.type; t.hasTag(CLASS);
2170 t = types.supertype(t)) {
2171 if (t != origin.type) {
2172 checkOverride(tree, t, origin, m);
2173 }
2174 for (Type t2 : types.interfaces(t)) {
2175 checkOverride(tree, t2, origin, m);
2176 }
2177 }
2178
2179 final boolean explicitOverride = m.attribute(syms.overrideType.tsym) != null;
2180 // Check if this method must override a super method due to being annotated with @Override
2181 // or by virtue of being a member of a diamond inferred anonymous class. Latter case is to
2182 // be treated "as if as they were annotated" with @Override.
2183 boolean mustOverride = explicitOverride ||
2184 (env.info.isAnonymousDiamond && !m.isConstructor() && !m.isPrivate());
2185 if (mustOverride && !isOverrider(m)) {
2186 DiagnosticPosition pos = tree.pos();
2187 for (JCAnnotation a : tree.getModifiers().annotations) {
2188 if (a.annotationType.type.tsym == syms.overrideType.tsym) {
2189 pos = a.pos();
2190 break;
2191 }
2192 }
2193 log.error(pos,
2194 explicitOverride ? (m.isStatic() ? Errors.StaticMethodsCannotBeAnnotatedWithOverride : Errors.MethodDoesNotOverrideSuperclass) :
2195 Errors.AnonymousDiamondMethodDoesNotOverrideSuperclass(Fragments.DiamondAnonymousMethodsImplicitlyOverride));
2196 }
2197 }
2198
2199 void checkOverride(JCTree tree, Type site, ClassSymbol origin, MethodSymbol m) {
2200 TypeSymbol c = site.tsym;
2201 for (Symbol sym : c.members().getSymbolsByName(m.name)) {
2202 if (m.overrides(sym, origin, types, false)) {
2203 if ((sym.flags() & ABSTRACT) == 0) {
2204 checkOverride(tree, m, (MethodSymbol)sym, origin);
2205 }
2206 }
2207 }
2208 }
2209
2210 private Predicate<Symbol> equalsHasCodeFilter = s -> MethodSymbol.implementation_filter.test(s) &&
2211 (s.flags() & BAD_OVERRIDE) == 0;
2212
2213 public void checkClassOverrideEqualsAndHashIfNeeded(DiagnosticPosition pos,
2214 ClassSymbol someClass) {
2215 /* At present, annotations cannot possibly have a method that is override
2216 * equivalent with Object.equals(Object) but in any case the condition is
2217 * fine for completeness.
2218 */
2219 if (someClass == (ClassSymbol)syms.objectType.tsym ||
2220 someClass.isInterface() || someClass.isEnum() ||
2221 (someClass.flags() & ANNOTATION) != 0 ||
2222 (someClass.flags() & ABSTRACT) != 0) return;
2223 //anonymous inner classes implementing interfaces need especial treatment
2224 if (someClass.isAnonymous()) {
2225 List<Type> interfaces = types.interfaces(someClass.type);
2226 if (interfaces != null && !interfaces.isEmpty() &&
2227 interfaces.head.tsym == syms.comparatorType.tsym) return;
2228 }
2229 checkClassOverrideEqualsAndHash(pos, someClass);
2230 }
2231
2232 private void checkClassOverrideEqualsAndHash(DiagnosticPosition pos,
2233 ClassSymbol someClass) {
2234 if (lint.isEnabled(LintCategory.OVERRIDES)) {
2235 MethodSymbol equalsAtObject = (MethodSymbol)syms.objectType
2236 .tsym.members().findFirst(names.equals);
2237 MethodSymbol hashCodeAtObject = (MethodSymbol)syms.objectType
2238 .tsym.members().findFirst(names.hashCode);
2239 MethodSymbol equalsImpl = types.implementation(equalsAtObject,
2240 someClass, false, equalsHasCodeFilter);
2241 boolean overridesEquals = equalsImpl != null &&
2242 equalsImpl.owner == someClass;
2243 boolean overridesHashCode = types.implementation(hashCodeAtObject,
2244 someClass, false, equalsHasCodeFilter) != hashCodeAtObject;
2245
2246 if (overridesEquals && !overridesHashCode) {
2247 log.warning(LintCategory.OVERRIDES, pos,
2248 Warnings.OverrideEqualsButNotHashcode(someClass));
2249 }
2250 }
2251 }
2252
2253 public void checkHasMain(DiagnosticPosition pos, ClassSymbol c) {
2254 boolean found = false;
2255
2256 for (Symbol sym : c.members().getSymbolsByName(names.main)) {
2257 if (sym.kind == MTH && (sym.flags() & PRIVATE) == 0) {
2258 MethodSymbol meth = (MethodSymbol)sym;
2259 if (!types.isSameType(meth.getReturnType(), syms.voidType)) {
2260 continue;
2261 }
2262 if (meth.params.isEmpty()) {
2263 found = true;
2264 break;
2265 }
2266 if (meth.params.size() != 1) {
2267 continue;
2268 }
2269 if (!types.isSameType(meth.params.head.type, types.makeArrayType(syms.stringType))) {
2270 continue;
2271 }
2272
2273 found = true;
2274 break;
2275 }
2276 }
2277
2278 if (!found) {
2279 log.error(pos, Errors.UnnamedClassDoesNotHaveMainMethod);
2280 }
2281 }
2282
2283 public void checkModuleName (JCModuleDecl tree) {
2284 Name moduleName = tree.sym.name;
2285 Assert.checkNonNull(moduleName);
2286 if (lint.isEnabled(LintCategory.MODULE)) {
2287 JCExpression qualId = tree.qualId;
2288 while (qualId != null) {
2289 Name componentName;
2290 DiagnosticPosition pos;
2291 switch (qualId.getTag()) {
2292 case SELECT:
2293 JCFieldAccess selectNode = ((JCFieldAccess) qualId);
2294 componentName = selectNode.name;
2295 pos = selectNode.pos();
2296 qualId = selectNode.selected;
2297 break;
2298 case IDENT:
2299 componentName = ((JCIdent) qualId).name;
2300 pos = qualId.pos();
2301 qualId = null;
2302 break;
2303 default:
2304 throw new AssertionError("Unexpected qualified identifier: " + qualId.toString());
2305 }
2306 if (componentName != null) {
2307 String moduleNameComponentString = componentName.toString();
2308 int nameLength = moduleNameComponentString.length();
2309 if (nameLength > 0 && Character.isDigit(moduleNameComponentString.charAt(nameLength - 1))) {
2310 log.warning(Lint.LintCategory.MODULE, pos, Warnings.PoorChoiceForModuleName(componentName));
2311 }
2312 }
2313 }
2314 }
2315 }
2316
2317 private boolean checkNameClash(ClassSymbol origin, Symbol s1, Symbol s2) {
2318 ClashFilter cf = new ClashFilter(origin.type);
2319 return (cf.test(s1) &&
2320 cf.test(s2) &&
2321 types.hasSameArgs(s1.erasure(types), s2.erasure(types)));
2322 }
2323
2324
2325 /** Check that all abstract members of given class have definitions.
2326 * @param pos Position to be used for error reporting.
2327 * @param c The class.
2328 */
2329 void checkAllDefined(DiagnosticPosition pos, ClassSymbol c) {
2330 MethodSymbol undef = types.firstUnimplementedAbstract(c);
2331 if (undef != null) {
2332 MethodSymbol undef1 =
2333 new MethodSymbol(undef.flags(), undef.name,
2334 types.memberType(c.type, undef), undef.owner);
2335 log.error(pos,
2336 Errors.DoesNotOverrideAbstract(c, undef1, undef1.location()));
2337 }
2338 }
2339
2340 void checkNonCyclicDecl(JCClassDecl tree) {
2341 CycleChecker cc = new CycleChecker();
2342 cc.scan(tree);
2343 if (!cc.errorFound && !cc.partialCheck) {
2344 tree.sym.flags_field |= ACYCLIC;
2345 }
2346 }
2347
2348 class CycleChecker extends TreeScanner {
2349
2350 Set<Symbol> seenClasses = new HashSet<>();
2351 boolean errorFound = false;
2352 boolean partialCheck = false;
2353
2354 private void checkSymbol(DiagnosticPosition pos, Symbol sym) {
2355 if (sym != null && sym.kind == TYP) {
2356 Env<AttrContext> classEnv = enter.getEnv((TypeSymbol)sym);
2357 if (classEnv != null) {
2358 DiagnosticSource prevSource = log.currentSource();
2359 try {
2360 log.useSource(classEnv.toplevel.sourcefile);
2361 scan(classEnv.tree);
2362 }
2363 finally {
2364 log.useSource(prevSource.getFile());
2365 }
2366 } else if (sym.kind == TYP) {
2367 checkClass(pos, sym, List.nil());
2368 }
2369 } else if (sym == null || sym.kind != PCK) {
2370 //not completed yet
2371 partialCheck = true;
2372 }
2373 }
2374
2375 @Override
2376 public void visitSelect(JCFieldAccess tree) {
2377 super.visitSelect(tree);
2378 checkSymbol(tree.pos(), tree.sym);
2379 }
2380
2381 @Override
2382 public void visitIdent(JCIdent tree) {
2383 checkSymbol(tree.pos(), tree.sym);
2384 }
2385
2386 @Override
2387 public void visitTypeApply(JCTypeApply tree) {
2388 scan(tree.clazz);
2389 }
2390
2391 @Override
2392 public void visitTypeArray(JCArrayTypeTree tree) {
2393 scan(tree.elemtype);
2394 }
2395
2396 @Override
2397 public void visitClassDef(JCClassDecl tree) {
2398 List<JCTree> supertypes = List.nil();
2399 if (tree.getExtendsClause() != null) {
2400 supertypes = supertypes.prepend(tree.getExtendsClause());
2401 }
2402 if (tree.getImplementsClause() != null) {
2403 for (JCTree intf : tree.getImplementsClause()) {
2404 supertypes = supertypes.prepend(intf);
2405 }
2406 }
2407 checkClass(tree.pos(), tree.sym, supertypes);
2408 }
2409
2410 void checkClass(DiagnosticPosition pos, Symbol c, List<JCTree> supertypes) {
2411 if ((c.flags_field & ACYCLIC) != 0)
2412 return;
2413 if (seenClasses.contains(c)) {
2414 errorFound = true;
2415 noteCyclic(pos, (ClassSymbol)c);
2416 } else if (!c.type.isErroneous()) {
2417 try {
2418 seenClasses.add(c);
2419 if (c.type.hasTag(CLASS)) {
2420 if (supertypes.nonEmpty()) {
2421 scan(supertypes);
2422 }
2423 else {
2424 ClassType ct = (ClassType)c.type;
2425 if (ct.supertype_field == null ||
2426 ct.interfaces_field == null) {
2427 //not completed yet
2428 partialCheck = true;
2429 return;
2430 }
2431 checkSymbol(pos, ct.supertype_field.tsym);
2432 for (Type intf : ct.interfaces_field) {
2433 checkSymbol(pos, intf.tsym);
2434 }
2435 }
2436 if (c.owner.kind == TYP) {
2437 checkSymbol(pos, c.owner);
2438 }
2439 }
2440 } finally {
2441 seenClasses.remove(c);
2442 }
2443 }
2444 }
2445 }
2446
2447 /** Check for cyclic references. Issue an error if the
2448 * symbol of the type referred to has a LOCKED flag set.
2449 *
2450 * @param pos Position to be used for error reporting.
2451 * @param t The type referred to.
2452 */
2453 void checkNonCyclic(DiagnosticPosition pos, Type t) {
2454 checkNonCyclicInternal(pos, t);
2455 }
2456
2457
2458 void checkNonCyclic(DiagnosticPosition pos, TypeVar t) {
2459 checkNonCyclic1(pos, t, List.nil());
2460 }
2461
2462 private void checkNonCyclic1(DiagnosticPosition pos, Type t, List<TypeVar> seen) {
2463 final TypeVar tv;
2464 if (t.hasTag(TYPEVAR) && (t.tsym.flags() & UNATTRIBUTED) != 0)
2465 return;
2466 if (seen.contains(t)) {
2467 tv = (TypeVar)t;
2468 tv.setUpperBound(types.createErrorType(t));
2469 log.error(pos, Errors.CyclicInheritance(t));
2470 } else if (t.hasTag(TYPEVAR)) {
2471 tv = (TypeVar)t;
2472 seen = seen.prepend(tv);
2473 for (Type b : types.getBounds(tv))
2474 checkNonCyclic1(pos, b, seen);
2475 }
2476 }
2477
2478 /** Check for cyclic references. Issue an error if the
2479 * symbol of the type referred to has a LOCKED flag set.
2480 *
2481 * @param pos Position to be used for error reporting.
2482 * @param t The type referred to.
2483 * @return True if the check completed on all attributed classes
2484 */
2485 private boolean checkNonCyclicInternal(DiagnosticPosition pos, Type t) {
2486 boolean complete = true; // was the check complete?
2487 //- System.err.println("checkNonCyclicInternal("+t+");");//DEBUG
2488 Symbol c = t.tsym;
2489 if ((c.flags_field & ACYCLIC) != 0) return true;
2490
2491 if ((c.flags_field & LOCKED) != 0) {
2492 noteCyclic(pos, (ClassSymbol)c);
2493 } else if (!c.type.isErroneous()) {
2494 try {
2495 c.flags_field |= LOCKED;
2496 if (c.type.hasTag(CLASS)) {
2497 ClassType clazz = (ClassType)c.type;
2498 if (clazz.interfaces_field != null)
2499 for (List<Type> l=clazz.interfaces_field; l.nonEmpty(); l=l.tail)
2500 complete &= checkNonCyclicInternal(pos, l.head);
2501 if (clazz.supertype_field != null) {
2502 Type st = clazz.supertype_field;
2503 if (st != null && st.hasTag(CLASS))
2504 complete &= checkNonCyclicInternal(pos, st);
2505 }
2506 if (c.owner.kind == TYP)
2507 complete &= checkNonCyclicInternal(pos, c.owner.type);
2508 }
2509 } finally {
2510 c.flags_field &= ~LOCKED;
2511 }
2512 }
2513 if (complete)
2514 complete = ((c.flags_field & UNATTRIBUTED) == 0) && c.isCompleted();
2515 if (complete) c.flags_field |= ACYCLIC;
2516 return complete;
2517 }
2518
2519 /** Note that we found an inheritance cycle. */
2520 private void noteCyclic(DiagnosticPosition pos, ClassSymbol c) {
2521 log.error(pos, Errors.CyclicInheritance(c));
2522 for (List<Type> l=types.interfaces(c.type); l.nonEmpty(); l=l.tail)
2523 l.head = types.createErrorType((ClassSymbol)l.head.tsym, Type.noType);
2524 Type st = types.supertype(c.type);
2525 if (st.hasTag(CLASS))
2526 ((ClassType)c.type).supertype_field = types.createErrorType((ClassSymbol)st.tsym, Type.noType);
2527 c.type = types.createErrorType(c, c.type);
2528 c.flags_field |= ACYCLIC;
2529 }
2530
2531 /** Check that all methods which implement some
2532 * method conform to the method they implement.
2533 * @param tree The class definition whose members are checked.
2534 */
2535 void checkImplementations(JCClassDecl tree) {
2536 checkImplementations(tree, tree.sym, tree.sym);
2537 }
2538 //where
2539 /** Check that all methods which implement some
2540 * method in `ic' conform to the method they implement.
2541 */
2542 void checkImplementations(JCTree tree, ClassSymbol origin, ClassSymbol ic) {
2543 for (List<Type> l = types.closure(ic.type); l.nonEmpty(); l = l.tail) {
2544 ClassSymbol lc = (ClassSymbol)l.head.tsym;
2545 if ((lc.flags() & ABSTRACT) != 0) {
2546 for (Symbol sym : lc.members().getSymbols(NON_RECURSIVE)) {
2547 if (sym.kind == MTH &&
2548 (sym.flags() & (STATIC|ABSTRACT)) == ABSTRACT) {
2549 MethodSymbol absmeth = (MethodSymbol)sym;
2550 MethodSymbol implmeth = absmeth.implementation(origin, types, false);
2551 if (implmeth != null && implmeth != absmeth &&
2552 (implmeth.owner.flags() & INTERFACE) ==
2553 (origin.flags() & INTERFACE)) {
2554 // don't check if implmeth is in a class, yet
2555 // origin is an interface. This case arises only
2556 // if implmeth is declared in Object. The reason is
2557 // that interfaces really don't inherit from
2558 // Object it's just that the compiler represents
2559 // things that way.
2560 checkOverride(tree, implmeth, absmeth, origin);
2561 }
2562 }
2563 }
2564 }
2565 }
2566 }
2567
2568 /** Check that all abstract methods implemented by a class are
2569 * mutually compatible.
2570 * @param pos Position to be used for error reporting.
2571 * @param c The class whose interfaces are checked.
2572 */
2573 void checkCompatibleSupertypes(DiagnosticPosition pos, Type c) {
2574 List<Type> supertypes = types.interfaces(c);
2575 Type supertype = types.supertype(c);
2576 if (supertype.hasTag(CLASS) &&
2577 (supertype.tsym.flags() & ABSTRACT) != 0)
2578 supertypes = supertypes.prepend(supertype);
2579 for (List<Type> l = supertypes; l.nonEmpty(); l = l.tail) {
2580 if (!l.head.getTypeArguments().isEmpty() &&
2581 !checkCompatibleAbstracts(pos, l.head, l.head, c))
2582 return;
2583 for (List<Type> m = supertypes; m != l; m = m.tail)
2584 if (!checkCompatibleAbstracts(pos, l.head, m.head, c))
2585 return;
2586 }
2587 checkCompatibleConcretes(pos, c);
2588 }
2589
2590 /** Check that all non-override equivalent methods accessible from 'site'
2591 * are mutually compatible (JLS 8.4.8/9.4.1).
2592 *
2593 * @param pos Position to be used for error reporting.
2594 * @param site The class whose methods are checked.
2595 * @param sym The method symbol to be checked.
2596 */
2597 void checkOverrideClashes(DiagnosticPosition pos, Type site, MethodSymbol sym) {
2598 ClashFilter cf = new ClashFilter(site);
2599 //for each method m1 that is overridden (directly or indirectly)
2600 //by method 'sym' in 'site'...
2601
2602 ArrayList<Symbol> symbolsByName = new ArrayList<>();
2603 types.membersClosure(site, false).getSymbolsByName(sym.name, cf).forEach(symbolsByName::add);
2604 for (Symbol m1 : symbolsByName) {
2605 if (!sym.overrides(m1, site.tsym, types, false)) {
2606 continue;
2607 }
2608
2609 //...check each method m2 that is a member of 'site'
2610 for (Symbol m2 : symbolsByName) {
2611 if (m2 == m1) continue;
2612 //if (i) the signature of 'sym' is not a subsignature of m1 (seen as
2613 //a member of 'site') and (ii) m1 has the same erasure as m2, issue an error
2614 if (!types.isSubSignature(sym.type, types.memberType(site, m2)) &&
2615 types.hasSameArgs(m2.erasure(types), m1.erasure(types))) {
2616 sym.flags_field |= CLASH;
2617 if (m1 == sym) {
2618 log.error(pos, Errors.NameClashSameErasureNoOverride(
2619 m1.name, types.memberType(site, m1).asMethodType().getParameterTypes(), m1.location(),
2620 m2.name, types.memberType(site, m2).asMethodType().getParameterTypes(), m2.location()));
2621 } else {
2622 ClassType ct = (ClassType)site;
2623 String kind = ct.isInterface() ? "interface" : "class";
2624 log.error(pos, Errors.NameClashSameErasureNoOverride1(
2625 kind,
2626 ct.tsym.name,
2627 m1.name,
2628 types.memberType(site, m1).asMethodType().getParameterTypes(),
2629 m1.location(),
2630 m2.name,
2631 types.memberType(site, m2).asMethodType().getParameterTypes(),
2632 m2.location()));
2633 }
2634 return;
2635 }
2636 }
2637 }
2638 }
2639
2640 /** Check that all static methods accessible from 'site' are
2641 * mutually compatible (JLS 8.4.8).
2642 *
2643 * @param pos Position to be used for error reporting.
2644 * @param site The class whose methods are checked.
2645 * @param sym The method symbol to be checked.
2646 */
2647 void checkHideClashes(DiagnosticPosition pos, Type site, MethodSymbol sym) {
2648 ClashFilter cf = new ClashFilter(site);
2649 //for each method m1 that is a member of 'site'...
2650 for (Symbol s : types.membersClosure(site, true).getSymbolsByName(sym.name, cf)) {
2651 //if (i) the signature of 'sym' is not a subsignature of m1 (seen as
2652 //a member of 'site') and (ii) 'sym' has the same erasure as m1, issue an error
2653 if (!types.isSubSignature(sym.type, types.memberType(site, s))) {
2654 if (types.hasSameArgs(s.erasure(types), sym.erasure(types))) {
2655 log.error(pos,
2656 Errors.NameClashSameErasureNoHide(sym, sym.location(), s, s.location()));
2657 return;
2658 }
2659 }
2660 }
2661 }
2662
2663 //where
2664 private class ClashFilter implements Predicate<Symbol> {
2665
2666 Type site;
2667
2668 ClashFilter(Type site) {
2669 this.site = site;
2670 }
2671
2672 boolean shouldSkip(Symbol s) {
2673 return (s.flags() & CLASH) != 0 &&
2674 s.owner == site.tsym;
2675 }
2676
2677 @Override
2678 public boolean test(Symbol s) {
2679 return s.kind == MTH &&
2680 (s.flags() & SYNTHETIC) == 0 &&
2681 !shouldSkip(s) &&
2682 s.isInheritedIn(site.tsym, types) &&
2683 !s.isConstructor();
2684 }
2685 }
2686
2687 void checkDefaultMethodClashes(DiagnosticPosition pos, Type site) {
2688 DefaultMethodClashFilter dcf = new DefaultMethodClashFilter(site);
2689 for (Symbol m : types.membersClosure(site, false).getSymbols(dcf)) {
2690 Assert.check(m.kind == MTH);
2691 List<MethodSymbol> prov = types.interfaceCandidates(site, (MethodSymbol)m);
2692 if (prov.size() > 1) {
2693 ListBuffer<Symbol> abstracts = new ListBuffer<>();
2694 ListBuffer<Symbol> defaults = new ListBuffer<>();
2695 for (MethodSymbol provSym : prov) {
2696 if ((provSym.flags() & DEFAULT) != 0) {
2697 defaults = defaults.append(provSym);
2698 } else if ((provSym.flags() & ABSTRACT) != 0) {
2699 abstracts = abstracts.append(provSym);
2700 }
2701 if (defaults.nonEmpty() && defaults.size() + abstracts.size() >= 2) {
2702 //strong semantics - issue an error if two sibling interfaces
2703 //have two override-equivalent defaults - or if one is abstract
2704 //and the other is default
2705 Fragment diagKey;
2706 Symbol s1 = defaults.first();
2707 Symbol s2;
2708 if (defaults.size() > 1) {
2709 s2 = defaults.toList().tail.head;
2710 diagKey = Fragments.IncompatibleUnrelatedDefaults(Kinds.kindName(site.tsym), site,
2711 m.name, types.memberType(site, m).getParameterTypes(),
2712 s1.location(), s2.location());
2713
2714 } else {
2715 s2 = abstracts.first();
2716 diagKey = Fragments.IncompatibleAbstractDefault(Kinds.kindName(site.tsym), site,
2717 m.name, types.memberType(site, m).getParameterTypes(),
2718 s1.location(), s2.location());
2719 }
2720 log.error(pos, Errors.TypesIncompatible(s1.location().type, s2.location().type, diagKey));
2721 break;
2722 }
2723 }
2724 }
2725 }
2726 }
2727
2728 //where
2729 private class DefaultMethodClashFilter implements Predicate<Symbol> {
2730
2731 Type site;
2732
2733 DefaultMethodClashFilter(Type site) {
2734 this.site = site;
2735 }
2736
2737 @Override
2738 public boolean test(Symbol s) {
2739 return s.kind == MTH &&
2740 (s.flags() & DEFAULT) != 0 &&
2741 s.isInheritedIn(site.tsym, types) &&
2742 !s.isConstructor();
2743 }
2744 }
2745
2746 /** Report warnings for potentially ambiguous method declarations in the given site. */
2747 void checkPotentiallyAmbiguousOverloads(JCClassDecl tree, Type site) {
2748
2749 // Skip if warning not enabled
2750 if (!lint.isEnabled(LintCategory.OVERLOADS))
2751 return;
2752
2753 // Gather all of site's methods, including overridden methods, grouped by name (except Object methods)
2754 List<java.util.List<MethodSymbol>> methodGroups = methodsGroupedByName(site,
2755 new PotentiallyAmbiguousFilter(site), ArrayList::new);
2756
2757 // Build the predicate that determines if site is responsible for an ambiguity
2758 BiPredicate<MethodSymbol, MethodSymbol> responsible = buildResponsiblePredicate(site, methodGroups);
2759
2760 // Now remove overridden methods from each group, leaving only site's actual members
2761 methodGroups.forEach(list -> removePreempted(list, (m1, m2) -> m1.overrides(m2, site.tsym, types, false)));
2762
2763 // Allow site's own declared methods (only) to apply @SuppressWarnings("overloads")
2764 methodGroups.forEach(list -> list.removeIf(
2765 m -> m.owner == site.tsym && !lint.augment(m).isEnabled(LintCategory.OVERLOADS)));
2766
2767 // Warn about ambiguous overload method pairs for which site is responsible
2768 methodGroups.forEach(list -> compareAndRemove(list, (m1, m2) -> {
2769
2770 // See if this is an ambiguous overload for which "site" is responsible
2771 if (!potentiallyAmbiguousOverload(site, m1, m2) || !responsible.test(m1, m2))
2772 return 0;
2773
2774 // Locate the warning at one of the methods, if possible
2775 DiagnosticPosition pos =
2776 m1.owner == site.tsym ? TreeInfo.diagnosticPositionFor(m1, tree) :
2777 m2.owner == site.tsym ? TreeInfo.diagnosticPositionFor(m2, tree) :
2778 tree.pos();
2779
2780 // Log the warning
2781 log.warning(LintCategory.OVERLOADS, pos,
2782 Warnings.PotentiallyAmbiguousOverload(
2783 m1.asMemberOf(site, types), m1.location(),
2784 m2.asMemberOf(site, types), m2.location()));
2785
2786 // Don't warn again for either of these two methods
2787 return FIRST | SECOND;
2788 }));
2789 }
2790
2791 /** Build a predicate that determines, given two methods that are members of the given class,
2792 * whether the class should be held "responsible" if the methods are potentially ambiguous.
2793 *
2794 * Sometimes ambiguous methods are unavoidable because they're inherited from a supertype.
2795 * For example, any subtype of Spliterator.OfInt will have ambiguities for both
2796 * forEachRemaining() and tryAdvance() (in both cases the overloads are IntConsumer and
2797 * Consumer<? super Integer>). So we only want to "blame" a class when that class is
2798 * itself responsible for creating the ambiguity. We declare that a class C is "responsible"
2799 * for the ambiguity between two methods m1 and m2 if there is no direct supertype T of C
2800 * such that m1 and m2, or some overrides thereof, both exist in T and are ambiguous in T.
2801 * As an optimization, we first check if either method is declared in C and does not override
2802 * any other methods; in this case the class is definitely responsible.
2803 */
2804 BiPredicate<MethodSymbol, MethodSymbol> buildResponsiblePredicate(Type site,
2805 List<? extends Collection<MethodSymbol>> methodGroups) {
2806
2807 // Define the "overrides" predicate
2808 BiPredicate<MethodSymbol, MethodSymbol> overrides = (m1, m2) -> m1.overrides(m2, site.tsym, types, false);
2809
2810 // Map each method declared in site to a list of the supertype method(s) it directly overrides
2811 HashMap<MethodSymbol, ArrayList<MethodSymbol>> overriddenMethodsMap = new HashMap<>();
2812 methodGroups.forEach(list -> {
2813 for (MethodSymbol m : list) {
2814
2815 // Skip methods not declared in site
2816 if (m.owner != site.tsym)
2817 continue;
2818
2819 // Gather all supertype methods overridden by m, directly or indirectly
2820 ArrayList<MethodSymbol> overriddenMethods = list.stream()
2821 .filter(m2 -> m2 != m && overrides.test(m, m2))
2822 .collect(Collectors.toCollection(ArrayList::new));
2823
2824 // Eliminate non-direct overrides
2825 removePreempted(overriddenMethods, overrides);
2826
2827 // Add to map
2828 overriddenMethodsMap.put(m, overriddenMethods);
2829 }
2830 });
2831
2832 // Build the predicate
2833 return (m1, m2) -> {
2834
2835 // Get corresponding supertype methods (if declared in site)
2836 java.util.List<MethodSymbol> overriddenMethods1 = overriddenMethodsMap.get(m1);
2837 java.util.List<MethodSymbol> overriddenMethods2 = overriddenMethodsMap.get(m2);
2838
2839 // Quick check for the case where a method was added by site itself
2840 if (overriddenMethods1 != null && overriddenMethods1.isEmpty())
2841 return true;
2842 if (overriddenMethods2 != null && overriddenMethods2.isEmpty())
2843 return true;
2844
2845 // Get each method's corresponding method(s) from supertypes of site
2846 java.util.List<MethodSymbol> supertypeMethods1 = overriddenMethods1 != null ?
2847 overriddenMethods1 : Collections.singletonList(m1);
2848 java.util.List<MethodSymbol> supertypeMethods2 = overriddenMethods2 != null ?
2849 overriddenMethods2 : Collections.singletonList(m2);
2850
2851 // See if we can blame some direct supertype instead
2852 return types.directSupertypes(site).stream()
2853 .filter(stype -> stype != syms.objectType)
2854 .map(stype -> stype.tsym.type) // view supertype in its original form
2855 .noneMatch(stype -> {
2856 for (MethodSymbol sm1 : supertypeMethods1) {
2857 if (!types.isSubtype(types.erasure(stype), types.erasure(sm1.owner.type)))
2858 continue;
2859 for (MethodSymbol sm2 : supertypeMethods2) {
2860 if (!types.isSubtype(types.erasure(stype), types.erasure(sm2.owner.type)))
2861 continue;
2862 if (potentiallyAmbiguousOverload(stype, sm1, sm2))
2863 return true;
2864 }
2865 }
2866 return false;
2867 });
2868 };
2869 }
2870
2871 /** Gather all of site's methods, including overridden methods, grouped and sorted by name,
2872 * after applying the given filter.
2873 */
2874 <C extends Collection<MethodSymbol>> List<C> methodsGroupedByName(Type site,
2875 Predicate<Symbol> filter, Supplier<? extends C> groupMaker) {
2876 Iterable<Symbol> symbols = types.membersClosure(site, false).getSymbols(filter, RECURSIVE);
2877 return StreamSupport.stream(symbols.spliterator(), false)
2878 .map(MethodSymbol.class::cast)
2879 .collect(Collectors.groupingBy(m -> m.name, Collectors.toCollection(groupMaker)))
2880 .entrySet()
2881 .stream()
2882 .sorted(Comparator.comparing(e -> e.getKey().toString()))
2883 .map(Map.Entry::getValue)
2884 .collect(List.collector());
2885 }
2886
2887 /** Compare elements in a list pair-wise in order to remove some of them.
2888 * @param list mutable list of items
2889 * @param comparer returns flag bit(s) to remove FIRST and/or SECOND
2890 */
2891 <T> void compareAndRemove(java.util.List<T> list, ToIntBiFunction<? super T, ? super T> comparer) {
2892 for (int index1 = 0; index1 < list.size() - 1; index1++) {
2893 T item1 = list.get(index1);
2894 for (int index2 = index1 + 1; index2 < list.size(); index2++) {
2895 T item2 = list.get(index2);
2896 int flags = comparer.applyAsInt(item1, item2);
2897 if ((flags & SECOND) != 0)
2898 list.remove(index2--); // remove item2
2899 if ((flags & FIRST) != 0) {
2900 list.remove(index1--); // remove item1
2901 break;
2902 }
2903 }
2904 }
2905 }
2906
2907 /** Remove elements in a list that are preempted by some other element in the list.
2908 * @param list mutable list of items
2909 * @param preempts decides if one item preempts another, causing the second one to be removed
2910 */
2911 <T> void removePreempted(java.util.List<T> list, BiPredicate<? super T, ? super T> preempts) {
2912 compareAndRemove(list, (item1, item2) -> {
2913 int flags = 0;
2914 if (preempts.test(item1, item2))
2915 flags |= SECOND;
2916 if (preempts.test(item2, item1))
2917 flags |= FIRST;
2918 return flags;
2919 });
2920 }
2921
2922 /** Filters method candidates for the "potentially ambiguous method" check */
2923 class PotentiallyAmbiguousFilter extends ClashFilter {
2924
2925 PotentiallyAmbiguousFilter(Type site) {
2926 super(site);
2927 }
2928
2929 @Override
2930 boolean shouldSkip(Symbol s) {
2931 return s.owner.type.tsym == syms.objectType.tsym || super.shouldSkip(s);
2932 }
2933 }
2934
2935 /**
2936 * Report warnings for potentially ambiguous method declarations. Two declarations
2937 * are potentially ambiguous if they feature two unrelated functional interface
2938 * in same argument position (in which case, a call site passing an implicit
2939 * lambda would be ambiguous). This assumes they already have the same name.
2940 */
2941 boolean potentiallyAmbiguousOverload(Type site, MethodSymbol msym1, MethodSymbol msym2) {
2942 Assert.check(msym1.name == msym2.name);
2943 if (msym1 == msym2)
2944 return false;
2945 Type mt1 = types.memberType(site, msym1);
2946 Type mt2 = types.memberType(site, msym2);
2947 //if both generic methods, adjust type variables
2948 if (mt1.hasTag(FORALL) && mt2.hasTag(FORALL) &&
2949 types.hasSameBounds((ForAll)mt1, (ForAll)mt2)) {
2950 mt2 = types.subst(mt2, ((ForAll)mt2).tvars, ((ForAll)mt1).tvars);
2951 }
2952 //expand varargs methods if needed
2953 int maxLength = Math.max(mt1.getParameterTypes().length(), mt2.getParameterTypes().length());
2954 List<Type> args1 = rs.adjustArgs(mt1.getParameterTypes(), msym1, maxLength, true);
2955 List<Type> args2 = rs.adjustArgs(mt2.getParameterTypes(), msym2, maxLength, true);
2956 //if arities don't match, exit
2957 if (args1.length() != args2.length())
2958 return false;
2959 boolean potentiallyAmbiguous = false;
2960 while (args1.nonEmpty() && args2.nonEmpty()) {
2961 Type s = args1.head;
2962 Type t = args2.head;
2963 if (!types.isSubtype(t, s) && !types.isSubtype(s, t)) {
2964 if (types.isFunctionalInterface(s) && types.isFunctionalInterface(t) &&
2965 types.findDescriptorType(s).getParameterTypes().length() > 0 &&
2966 types.findDescriptorType(s).getParameterTypes().length() ==
2967 types.findDescriptorType(t).getParameterTypes().length()) {
2968 potentiallyAmbiguous = true;
2969 } else {
2970 return false;
2971 }
2972 }
2973 args1 = args1.tail;
2974 args2 = args2.tail;
2975 }
2976 return potentiallyAmbiguous;
2977 }
2978
2979 void checkAccessFromSerializableElement(final JCTree tree, boolean isLambda) {
2980 if (warnOnAnyAccessToMembers ||
2981 (lint.isEnabled(LintCategory.SERIAL) &&
2982 !lint.isSuppressed(LintCategory.SERIAL) &&
2983 isLambda)) {
2984 Symbol sym = TreeInfo.symbol(tree);
2985 if (!sym.kind.matches(KindSelector.VAL_MTH)) {
2986 return;
2987 }
2988
2989 if (sym.kind == VAR) {
2990 if ((sym.flags() & PARAMETER) != 0 ||
2991 sym.isDirectlyOrIndirectlyLocal() ||
2992 sym.name == names._this ||
2993 sym.name == names._super) {
2994 return;
2995 }
2996 }
2997
2998 if (!types.isSubtype(sym.owner.type, syms.serializableType) &&
2999 isEffectivelyNonPublic(sym)) {
3000 if (isLambda) {
3001 if (belongsToRestrictedPackage(sym)) {
3002 log.warning(LintCategory.SERIAL, tree.pos(),
3003 Warnings.AccessToMemberFromSerializableLambda(sym));
3004 }
3005 } else {
3006 log.warning(tree.pos(),
3007 Warnings.AccessToMemberFromSerializableElement(sym));
3008 }
3009 }
3010 }
3011 }
3012
3013 private boolean isEffectivelyNonPublic(Symbol sym) {
3014 if (sym.packge() == syms.rootPackage) {
3015 return false;
3016 }
3017
3018 while (sym.kind != PCK) {
3019 if ((sym.flags() & PUBLIC) == 0) {
3020 return true;
3021 }
3022 sym = sym.owner;
3023 }
3024 return false;
3025 }
3026
3027 private boolean belongsToRestrictedPackage(Symbol sym) {
3028 String fullName = sym.packge().fullname.toString();
3029 return fullName.startsWith("java.") ||
3030 fullName.startsWith("javax.") ||
3031 fullName.startsWith("sun.") ||
3032 fullName.contains(".internal.");
3033 }
3034
3035 /** Check that class c does not implement directly or indirectly
3036 * the same parameterized interface with two different argument lists.
3037 * @param pos Position to be used for error reporting.
3038 * @param type The type whose interfaces are checked.
3039 */
3040 void checkClassBounds(DiagnosticPosition pos, Type type) {
3041 checkClassBounds(pos, new HashMap<TypeSymbol,Type>(), type);
3042 }
3043 //where
3044 /** Enter all interfaces of type `type' into the hash table `seensofar'
3045 * with their class symbol as key and their type as value. Make
3046 * sure no class is entered with two different types.
3047 */
3048 void checkClassBounds(DiagnosticPosition pos,
3049 Map<TypeSymbol,Type> seensofar,
3050 Type type) {
3051 if (type.isErroneous()) return;
3052 for (List<Type> l = types.interfaces(type); l.nonEmpty(); l = l.tail) {
3053 Type it = l.head;
3054 if (type.hasTag(CLASS) && !it.hasTag(CLASS)) continue; // JLS 8.1.5
3055
3056 Type oldit = seensofar.put(it.tsym, it);
3057 if (oldit != null) {
3058 List<Type> oldparams = oldit.allparams();
3059 List<Type> newparams = it.allparams();
3060 if (!types.containsTypeEquivalent(oldparams, newparams))
3061 log.error(pos,
3062 Errors.CantInheritDiffArg(it.tsym,
3063 Type.toString(oldparams),
3064 Type.toString(newparams)));
3065 }
3066 checkClassBounds(pos, seensofar, it);
3067 }
3068 Type st = types.supertype(type);
3069 if (type.hasTag(CLASS) && !st.hasTag(CLASS)) return; // JLS 8.1.4
3070 if (st != Type.noType) checkClassBounds(pos, seensofar, st);
3071 }
3072
3073 /** Enter interface into into set.
3074 * If it existed already, issue a "repeated interface" error.
3075 */
3076 void checkNotRepeated(DiagnosticPosition pos, Type it, Set<Symbol> its) {
3077 if (its.contains(it.tsym))
3078 log.error(pos, Errors.RepeatedInterface);
3079 else {
3080 its.add(it.tsym);
3081 }
3082 }
3083
3084 /* *************************************************************************
3085 * Check annotations
3086 **************************************************************************/
3087
3088 /**
3089 * Recursively validate annotations values
3090 */
3091 void validateAnnotationTree(JCTree tree) {
3092 class AnnotationValidator extends TreeScanner {
3093 @Override
3094 public void visitAnnotation(JCAnnotation tree) {
3095 if (!tree.type.isErroneous() && tree.type.tsym.isAnnotationType()) {
3096 super.visitAnnotation(tree);
3097 validateAnnotation(tree);
3098 }
3099 }
3100 }
3101 tree.accept(new AnnotationValidator());
3102 }
3103
3104 /**
3105 * {@literal
3106 * Annotation types are restricted to primitives, String, an
3107 * enum, an annotation, Class, Class<?>, Class<? extends
3108 * Anything>, arrays of the preceding.
3109 * }
3110 */
3111 void validateAnnotationType(JCTree restype) {
3112 // restype may be null if an error occurred, so don't bother validating it
3113 if (restype != null) {
3114 validateAnnotationType(restype.pos(), restype.type);
3115 }
3116 }
3117
3118 void validateAnnotationType(DiagnosticPosition pos, Type type) {
3119 if (type.isPrimitive()) return;
3120 if (types.isSameType(type, syms.stringType)) return;
3121 if ((type.tsym.flags() & Flags.ENUM) != 0) return;
3122 if ((type.tsym.flags() & Flags.ANNOTATION) != 0) return;
3123 if (types.cvarLowerBound(type).tsym == syms.classType.tsym) return;
3124 if (types.isArray(type) && !types.isArray(types.elemtype(type))) {
3125 validateAnnotationType(pos, types.elemtype(type));
3126 return;
3127 }
3128 log.error(pos, Errors.InvalidAnnotationMemberType);
3129 }
3130
3131 /**
3132 * "It is also a compile-time error if any method declared in an
3133 * annotation type has a signature that is override-equivalent to
3134 * that of any public or protected method declared in class Object
3135 * or in the interface annotation.Annotation."
3136 *
3137 * @jls 9.6 Annotation Types
3138 */
3139 void validateAnnotationMethod(DiagnosticPosition pos, MethodSymbol m) {
3140 for (Type sup = syms.annotationType; sup.hasTag(CLASS); sup = types.supertype(sup)) {
3141 Scope s = sup.tsym.members();
3142 for (Symbol sym : s.getSymbolsByName(m.name)) {
3143 if (sym.kind == MTH &&
3144 (sym.flags() & (PUBLIC | PROTECTED)) != 0 &&
3145 types.overrideEquivalent(m.type, sym.type))
3146 log.error(pos, Errors.IntfAnnotationMemberClash(sym, sup));
3147 }
3148 }
3149 }
3150
3151 /** Check the annotations of a symbol.
3152 */
3153 public void validateAnnotations(List<JCAnnotation> annotations, JCTree declarationTree, Symbol s) {
3154 for (JCAnnotation a : annotations)
3155 validateAnnotation(a, declarationTree, s);
3156 }
3157
3158 /** Check the type annotations.
3159 */
3160 public void validateTypeAnnotations(List<JCAnnotation> annotations, Symbol s, boolean isTypeParameter) {
3161 for (JCAnnotation a : annotations)
3162 validateTypeAnnotation(a, s, isTypeParameter);
3163 }
3164
3165 /** Check an annotation of a symbol.
3166 */
3167 private void validateAnnotation(JCAnnotation a, JCTree declarationTree, Symbol s) {
3168 /** NOTE: if annotation processors are present, annotation processing rounds can happen after this method,
3169 * this can impact in particular records for which annotations are forcibly propagated.
3170 */
3171 validateAnnotationTree(a);
3172 boolean isRecordMember = ((s.flags_field & RECORD) != 0 || s.enclClass() != null && s.enclClass().isRecord());
3173
3174 boolean isRecordField = (s.flags_field & RECORD) != 0 &&
3175 declarationTree.hasTag(VARDEF) &&
3176 s.owner.kind == TYP;
3177
3178 if (isRecordField) {
3179 // first we need to check if the annotation is applicable to records
3180 Name[] targets = getTargetNames(a);
3181 boolean appliesToRecords = false;
3182 for (Name target : targets) {
3183 appliesToRecords =
3184 target == names.FIELD ||
3185 target == names.PARAMETER ||
3186 target == names.METHOD ||
3187 target == names.TYPE_USE ||
3188 target == names.RECORD_COMPONENT;
3189 if (appliesToRecords) {
3190 break;
3191 }
3192 }
3193 if (!appliesToRecords) {
3194 log.error(a.pos(), Errors.AnnotationTypeNotApplicable);
3195 } else {
3196 /* lets now find the annotations in the field that are targeted to record components and append them to
3197 * the corresponding record component
3198 */
3199 ClassSymbol recordClass = (ClassSymbol) s.owner;
3200 RecordComponent rc = recordClass.getRecordComponent((VarSymbol)s);
3201 SymbolMetadata metadata = rc.getMetadata();
3202 if (metadata == null || metadata.isEmpty()) {
3203 /* if not is empty then we have already been here, which is the case if multiple annotations are applied
3204 * to the record component declaration
3205 */
3206 rc.appendAttributes(s.getRawAttributes().stream().filter(anno ->
3207 Arrays.stream(getTargetNames(anno.type.tsym)).anyMatch(name -> name == names.RECORD_COMPONENT)
3208 ).collect(List.collector()));
3209
3210 JCVariableDecl fieldAST = (JCVariableDecl) declarationTree;
3211 for (JCAnnotation fieldAnnot : fieldAST.mods.annotations) {
3212 for (JCAnnotation rcAnnot : rc.declarationFor().mods.annotations) {
3213 if (rcAnnot.pos == fieldAnnot.pos) {
3214 rcAnnot.setType(fieldAnnot.type);
3215 break;
3216 }
3217 }
3218 }
3219
3220 /* At this point, we used to carry over any type annotations from the VARDEF to the record component, but
3221 * that is problematic, since we get here only when *some* annotation is applied to the SE5 (declaration)
3222 * annotation location, inadvertently failing to carry over the type annotations when the VarDef has no
3223 * annotations in the SE5 annotation location.
3224 *
3225 * Now type annotations are assigned to record components in a method that would execute irrespective of
3226 * whether there are SE5 annotations on a VarDef viz com.sun.tools.javac.code.TypeAnnotations.TypeAnnotationPositions.visitVarDef
3227 */
3228 }
3229 }
3230 }
3231
3232 /* the section below is tricky. Annotations applied to record components are propagated to the corresponding
3233 * record member so if an annotation has target: FIELD, it is propagated to the corresponding FIELD, if it has
3234 * target METHOD, it is propagated to the accessor and so on. But at the moment when method members are generated
3235 * there is no enough information to propagate only the right annotations. So all the annotations are propagated
3236 * to all the possible locations.
3237 *
3238 * At this point we need to remove all the annotations that are not in place before going on with the annotation
3239 * party. On top of the above there is the issue that there is no AST representing record components, just symbols
3240 * so the corresponding field has been holding all the annotations and it's metadata has been modified as if it
3241 * was both a field and a record component.
3242 *
3243 * So there are two places where we need to trim annotations from: the metadata of the symbol and / or the modifiers
3244 * in the AST. Whatever is in the metadata will be written to the class file, whatever is in the modifiers could
3245 * be see by annotation processors.
3246 *
3247 * The metadata contains both type annotations and declaration annotations. At this point of the game we don't
3248 * need to care about type annotations, they are all in the right place. But we could need to remove declaration
3249 * annotations. So for declaration annotations if they are not applicable to the record member, excluding type
3250 * annotations which are already correct, then we will remove it. For the AST modifiers if the annotation is not
3251 * applicable either as type annotation and or declaration annotation, only in that case it will be removed.
3252 *
3253 * So it could be that annotation is removed as a declaration annotation but it is kept in the AST modifier for
3254 * further inspection by annotation processors.
3255 *
3256 * For example:
3257 *
3258 * import java.lang.annotation.*;
3259 *
3260 * @Target({ElementType.TYPE_USE, ElementType.RECORD_COMPONENT})
3261 * @Retention(RetentionPolicy.RUNTIME)
3262 * @interface Anno { }
3263 *
3264 * record R(@Anno String s) {}
3265 *
3266 * at this point we will have for the case of the generated field:
3267 * - @Anno in the modifier
3268 * - @Anno as a type annotation
3269 * - @Anno as a declaration annotation
3270 *
3271 * the last one should be removed because the annotation has not FIELD as target but it was applied as a
3272 * declaration annotation because the field was being treated both as a field and as a record component
3273 * as we have already copied the annotations to the record component, now the field doesn't need to hold
3274 * annotations that are not intended for it anymore. Still @Anno has to be kept in the AST's modifiers as it
3275 * is applicable as a type annotation to the type of the field.
3276 */
3277
3278 if (a.type.tsym.isAnnotationType()) {
3279 Optional<Set<Name>> applicableTargetsOp = getApplicableTargets(a, s);
3280 if (!applicableTargetsOp.isEmpty()) {
3281 Set<Name> applicableTargets = applicableTargetsOp.get();
3282 boolean notApplicableOrIsTypeUseOnly = applicableTargets.isEmpty() ||
3283 applicableTargets.size() == 1 && applicableTargets.contains(names.TYPE_USE);
3284 boolean isCompGeneratedRecordElement = isRecordMember && (s.flags_field & Flags.GENERATED_MEMBER) != 0;
3285 boolean isCompRecordElementWithNonApplicableDeclAnno = isCompGeneratedRecordElement && notApplicableOrIsTypeUseOnly;
3286
3287 if (applicableTargets.isEmpty() || isCompRecordElementWithNonApplicableDeclAnno) {
3288 if (isCompRecordElementWithNonApplicableDeclAnno) {
3289 /* so we have found an annotation that is not applicable to a record member that was generated by the
3290 * compiler. This was intentionally done at TypeEnter, now is the moment strip away the annotations
3291 * that are not applicable to the given record member
3292 */
3293 JCModifiers modifiers = TreeInfo.getModifiers(declarationTree);
3294 /* lets first remove the annotation from the modifier if it is not applicable, we have to check again as
3295 * it could be a type annotation
3296 */
3297 if (modifiers != null && applicableTargets.isEmpty()) {
3298 ListBuffer<JCAnnotation> newAnnotations = new ListBuffer<>();
3299 for (JCAnnotation anno : modifiers.annotations) {
3300 if (anno != a) {
3301 newAnnotations.add(anno);
3302 }
3303 }
3304 modifiers.annotations = newAnnotations.toList();
3305 }
3306 // now lets remove it from the symbol
3307 s.getMetadata().removeDeclarationMetadata(a.attribute);
3308 } else {
3309 log.error(a.pos(), Errors.AnnotationTypeNotApplicable);
3310 }
3311 }
3312 /* if we are seeing the @SafeVarargs annotation applied to a compiler generated accessor,
3313 * then this is an error as we know that no compiler generated accessor will be a varargs
3314 * method, better to fail asap
3315 */
3316 if (isCompGeneratedRecordElement && !isRecordField && a.type.tsym == syms.trustMeType.tsym && declarationTree.hasTag(METHODDEF)) {
3317 log.error(a.pos(), Errors.VarargsInvalidTrustmeAnno(syms.trustMeType.tsym, Fragments.VarargsTrustmeOnNonVarargsAccessor(s)));
3318 }
3319 }
3320 }
3321
3322 if (a.annotationType.type.tsym == syms.functionalInterfaceType.tsym) {
3323 if (s.kind != TYP) {
3324 log.error(a.pos(), Errors.BadFunctionalIntfAnno);
3325 } else if (!s.isInterface() || (s.flags() & ANNOTATION) != 0) {
3326 log.error(a.pos(), Errors.BadFunctionalIntfAnno1(Fragments.NotAFunctionalIntf(s)));
3327 }
3328 }
3329 }
3330
3331 public void validateTypeAnnotation(JCAnnotation a, Symbol s, boolean isTypeParameter) {
3332 Assert.checkNonNull(a.type);
3333 // we just want to validate that the anotation doesn't have any wrong target
3334 if (s != null) getApplicableTargets(a, s);
3335 validateAnnotationTree(a);
3336
3337 if (a.hasTag(TYPE_ANNOTATION) &&
3338 !a.annotationType.type.isErroneous() &&
3339 !isTypeAnnotation(a, isTypeParameter)) {
3340 log.error(a.pos(), Errors.AnnotationTypeNotApplicableToType(a.type));
3341 }
3342 }
3343
3344 /**
3345 * Validate the proposed container 'repeatable' on the
3346 * annotation type symbol 's'. Report errors at position
3347 * 'pos'.
3348 *
3349 * @param s The (annotation)type declaration annotated with a @Repeatable
3350 * @param repeatable the @Repeatable on 's'
3351 * @param pos where to report errors
3352 */
3353 public void validateRepeatable(TypeSymbol s, Attribute.Compound repeatable, DiagnosticPosition pos) {
3354 Assert.check(types.isSameType(repeatable.type, syms.repeatableType));
3355
3356 Type t = null;
3357 List<Pair<MethodSymbol,Attribute>> l = repeatable.values;
3358 if (!l.isEmpty()) {
3359 Assert.check(l.head.fst.name == names.value);
3360 if (l.head.snd instanceof Attribute.Class) {
3361 t = ((Attribute.Class)l.head.snd).getValue();
3362 }
3363 }
3364
3365 if (t == null) {
3366 // errors should already have been reported during Annotate
3367 return;
3368 }
3369
3370 validateValue(t.tsym, s, pos);
3371 validateRetention(t.tsym, s, pos);
3372 validateDocumented(t.tsym, s, pos);
3373 validateInherited(t.tsym, s, pos);
3374 validateTarget(t.tsym, s, pos);
3375 validateDefault(t.tsym, pos);
3376 }
3377
3378 private void validateValue(TypeSymbol container, TypeSymbol contained, DiagnosticPosition pos) {
3379 Symbol sym = container.members().findFirst(names.value);
3380 if (sym != null && sym.kind == MTH) {
3381 MethodSymbol m = (MethodSymbol) sym;
3382 Type ret = m.getReturnType();
3383 if (!(ret.hasTag(ARRAY) && types.isSameType(((ArrayType)ret).elemtype, contained.type))) {
3384 log.error(pos,
3385 Errors.InvalidRepeatableAnnotationValueReturn(container,
3386 ret,
3387 types.makeArrayType(contained.type)));
3388 }
3389 } else {
3390 log.error(pos, Errors.InvalidRepeatableAnnotationNoValue(container));
3391 }
3392 }
3393
3394 private void validateRetention(TypeSymbol container, TypeSymbol contained, DiagnosticPosition pos) {
3395 Attribute.RetentionPolicy containerRetention = types.getRetention(container);
3396 Attribute.RetentionPolicy containedRetention = types.getRetention(contained);
3397
3398 boolean error = false;
3399 switch (containedRetention) {
3400 case RUNTIME:
3401 if (containerRetention != Attribute.RetentionPolicy.RUNTIME) {
3402 error = true;
3403 }
3404 break;
3405 case CLASS:
3406 if (containerRetention == Attribute.RetentionPolicy.SOURCE) {
3407 error = true;
3408 }
3409 }
3410 if (error ) {
3411 log.error(pos,
3412 Errors.InvalidRepeatableAnnotationRetention(container,
3413 containerRetention.name(),
3414 contained,
3415 containedRetention.name()));
3416 }
3417 }
3418
3419 private void validateDocumented(Symbol container, Symbol contained, DiagnosticPosition pos) {
3420 if (contained.attribute(syms.documentedType.tsym) != null) {
3421 if (container.attribute(syms.documentedType.tsym) == null) {
3422 log.error(pos, Errors.InvalidRepeatableAnnotationNotDocumented(container, contained));
3423 }
3424 }
3425 }
3426
3427 private void validateInherited(Symbol container, Symbol contained, DiagnosticPosition pos) {
3428 if (contained.attribute(syms.inheritedType.tsym) != null) {
3429 if (container.attribute(syms.inheritedType.tsym) == null) {
3430 log.error(pos, Errors.InvalidRepeatableAnnotationNotInherited(container, contained));
3431 }
3432 }
3433 }
3434
3435 private void validateTarget(TypeSymbol container, TypeSymbol contained, DiagnosticPosition pos) {
3436 // The set of targets the container is applicable to must be a subset
3437 // (with respect to annotation target semantics) of the set of targets
3438 // the contained is applicable to. The target sets may be implicit or
3439 // explicit.
3440
3441 Set<Name> containerTargets;
3442 Attribute.Array containerTarget = getAttributeTargetAttribute(container);
3443 if (containerTarget == null) {
3444 containerTargets = getDefaultTargetSet();
3445 } else {
3446 containerTargets = new HashSet<>();
3447 for (Attribute app : containerTarget.values) {
3448 if (!(app instanceof Attribute.Enum attributeEnum)) {
3449 continue; // recovery
3450 }
3451 containerTargets.add(attributeEnum.value.name);
3452 }
3453 }
3454
3455 Set<Name> containedTargets;
3456 Attribute.Array containedTarget = getAttributeTargetAttribute(contained);
3457 if (containedTarget == null) {
3458 containedTargets = getDefaultTargetSet();
3459 } else {
3460 containedTargets = new HashSet<>();
3461 for (Attribute app : containedTarget.values) {
3462 if (!(app instanceof Attribute.Enum attributeEnum)) {
3463 continue; // recovery
3464 }
3465 containedTargets.add(attributeEnum.value.name);
3466 }
3467 }
3468
3469 if (!isTargetSubsetOf(containerTargets, containedTargets)) {
3470 log.error(pos, Errors.InvalidRepeatableAnnotationIncompatibleTarget(container, contained));
3471 }
3472 }
3473
3474 /* get a set of names for the default target */
3475 private Set<Name> getDefaultTargetSet() {
3476 if (defaultTargets == null) {
3477 defaultTargets = Set.of(defaultTargetMetaInfo());
3478 }
3479
3480 return defaultTargets;
3481 }
3482 private Set<Name> defaultTargets;
3483
3484
3485 /** Checks that s is a subset of t, with respect to ElementType
3486 * semantics, specifically {ANNOTATION_TYPE} is a subset of {TYPE},
3487 * and {TYPE_USE} covers the set {ANNOTATION_TYPE, TYPE, TYPE_USE,
3488 * TYPE_PARAMETER}.
3489 */
3490 private boolean isTargetSubsetOf(Set<Name> s, Set<Name> t) {
3491 // Check that all elements in s are present in t
3492 for (Name n2 : s) {
3493 boolean currentElementOk = false;
3494 for (Name n1 : t) {
3495 if (n1 == n2) {
3496 currentElementOk = true;
3497 break;
3498 } else if (n1 == names.TYPE && n2 == names.ANNOTATION_TYPE) {
3499 currentElementOk = true;
3500 break;
3501 } else if (n1 == names.TYPE_USE &&
3502 (n2 == names.TYPE ||
3503 n2 == names.ANNOTATION_TYPE ||
3504 n2 == names.TYPE_PARAMETER)) {
3505 currentElementOk = true;
3506 break;
3507 }
3508 }
3509 if (!currentElementOk)
3510 return false;
3511 }
3512 return true;
3513 }
3514
3515 private void validateDefault(Symbol container, DiagnosticPosition pos) {
3516 // validate that all other elements of containing type has defaults
3517 Scope scope = container.members();
3518 for(Symbol elm : scope.getSymbols()) {
3519 if (elm.name != names.value &&
3520 elm.kind == MTH &&
3521 ((MethodSymbol)elm).defaultValue == null) {
3522 log.error(pos,
3523 Errors.InvalidRepeatableAnnotationElemNondefault(container, elm));
3524 }
3525 }
3526 }
3527
3528 /** Is s a method symbol that overrides a method in a superclass? */
3529 boolean isOverrider(Symbol s) {
3530 if (s.kind != MTH || s.isStatic())
3531 return false;
3532 MethodSymbol m = (MethodSymbol)s;
3533 TypeSymbol owner = (TypeSymbol)m.owner;
3534 for (Type sup : types.closure(owner.type)) {
3535 if (sup == owner.type)
3536 continue; // skip "this"
3537 Scope scope = sup.tsym.members();
3538 for (Symbol sym : scope.getSymbolsByName(m.name)) {
3539 if (!sym.isStatic() && m.overrides(sym, owner, types, true))
3540 return true;
3541 }
3542 }
3543 return false;
3544 }
3545
3546 /** Is the annotation applicable to types? */
3547 protected boolean isTypeAnnotation(JCAnnotation a, boolean isTypeParameter) {
3548 List<Attribute> targets = typeAnnotations.annotationTargets(a.annotationType.type.tsym);
3549 return (targets == null) ?
3550 (Feature.NO_TARGET_ANNOTATION_APPLICABILITY.allowedInSource(source) && isTypeParameter) :
3551 targets.stream()
3552 .anyMatch(attr -> isTypeAnnotation(attr, isTypeParameter));
3553 }
3554 //where
3555 boolean isTypeAnnotation(Attribute a, boolean isTypeParameter) {
3556 Attribute.Enum e = (Attribute.Enum)a;
3557 return (e.value.name == names.TYPE_USE ||
3558 (isTypeParameter && e.value.name == names.TYPE_PARAMETER));
3559 }
3560
3561 /** Is the annotation applicable to the symbol? */
3562 Name[] getTargetNames(JCAnnotation a) {
3563 return getTargetNames(a.annotationType.type.tsym);
3564 }
3565
3566 public Name[] getTargetNames(TypeSymbol annoSym) {
3567 Attribute.Array arr = getAttributeTargetAttribute(annoSym);
3568 Name[] targets;
3569 if (arr == null) {
3570 targets = defaultTargetMetaInfo();
3571 } else {
3572 // TODO: can we optimize this?
3573 targets = new Name[arr.values.length];
3574 for (int i=0; i<arr.values.length; ++i) {
3575 Attribute app = arr.values[i];
3576 if (!(app instanceof Attribute.Enum attributeEnum)) {
3577 return new Name[0];
3578 }
3579 targets[i] = attributeEnum.value.name;
3580 }
3581 }
3582 return targets;
3583 }
3584
3585 boolean annotationApplicable(JCAnnotation a, Symbol s) {
3586 Optional<Set<Name>> targets = getApplicableTargets(a, s);
3587 /* the optional could be empty if the annotation is unknown in that case
3588 * we return that it is applicable and if it is erroneous that should imply
3589 * an error at the declaration site
3590 */
3591 return targets.isEmpty() || targets.isPresent() && !targets.get().isEmpty();
3592 }
3593
3594 Optional<Set<Name>> getApplicableTargets(JCAnnotation a, Symbol s) {
3595 Attribute.Array arr = getAttributeTargetAttribute(a.annotationType.type.tsym);
3596 Name[] targets;
3597 Set<Name> applicableTargets = new HashSet<>();
3598
3599 if (arr == null) {
3600 targets = defaultTargetMetaInfo();
3601 } else {
3602 // TODO: can we optimize this?
3603 targets = new Name[arr.values.length];
3604 for (int i=0; i<arr.values.length; ++i) {
3605 Attribute app = arr.values[i];
3606 if (!(app instanceof Attribute.Enum attributeEnum)) {
3607 // recovery
3608 return Optional.empty();
3609 }
3610 targets[i] = attributeEnum.value.name;
3611 }
3612 }
3613 for (Name target : targets) {
3614 if (target == names.TYPE) {
3615 if (s.kind == TYP)
3616 applicableTargets.add(names.TYPE);
3617 } else if (target == names.FIELD) {
3618 if (s.kind == VAR && s.owner.kind != MTH)
3619 applicableTargets.add(names.FIELD);
3620 } else if (target == names.RECORD_COMPONENT) {
3621 if (s.getKind() == ElementKind.RECORD_COMPONENT) {
3622 applicableTargets.add(names.RECORD_COMPONENT);
3623 }
3624 } else if (target == names.METHOD) {
3625 if (s.kind == MTH && !s.isConstructor())
3626 applicableTargets.add(names.METHOD);
3627 } else if (target == names.PARAMETER) {
3628 if (s.kind == VAR &&
3629 (s.owner.kind == MTH && (s.flags() & PARAMETER) != 0)) {
3630 applicableTargets.add(names.PARAMETER);
3631 }
3632 } else if (target == names.CONSTRUCTOR) {
3633 if (s.kind == MTH && s.isConstructor())
3634 applicableTargets.add(names.CONSTRUCTOR);
3635 } else if (target == names.LOCAL_VARIABLE) {
3636 if (s.kind == VAR && s.owner.kind == MTH &&
3637 (s.flags() & PARAMETER) == 0) {
3638 applicableTargets.add(names.LOCAL_VARIABLE);
3639 }
3640 } else if (target == names.ANNOTATION_TYPE) {
3641 if (s.kind == TYP && (s.flags() & ANNOTATION) != 0) {
3642 applicableTargets.add(names.ANNOTATION_TYPE);
3643 }
3644 } else if (target == names.PACKAGE) {
3645 if (s.kind == PCK)
3646 applicableTargets.add(names.PACKAGE);
3647 } else if (target == names.TYPE_USE) {
3648 if (s.kind == VAR && s.owner.kind == MTH && s.type.hasTag(NONE)) {
3649 //cannot type annotate implicitly typed locals
3650 continue;
3651 } else if (s.kind == TYP || s.kind == VAR ||
3652 (s.kind == MTH && !s.isConstructor() &&
3653 !s.type.getReturnType().hasTag(VOID)) ||
3654 (s.kind == MTH && s.isConstructor())) {
3655 applicableTargets.add(names.TYPE_USE);
3656 }
3657 } else if (target == names.TYPE_PARAMETER) {
3658 if (s.kind == TYP && s.type.hasTag(TYPEVAR))
3659 applicableTargets.add(names.TYPE_PARAMETER);
3660 } else if (target == names.MODULE) {
3661 if (s.kind == MDL)
3662 applicableTargets.add(names.MODULE);
3663 } else {
3664 log.error(a, Errors.AnnotationUnrecognizedAttributeName(a.type, target));
3665 return Optional.empty(); // Unknown ElementType
3666 }
3667 }
3668 return Optional.of(applicableTargets);
3669 }
3670
3671 Attribute.Array getAttributeTargetAttribute(TypeSymbol s) {
3672 Attribute.Compound atTarget = s.getAnnotationTypeMetadata().getTarget();
3673 if (atTarget == null) return null; // ok, is applicable
3674 Attribute atValue = atTarget.member(names.value);
3675 return (atValue instanceof Attribute.Array attributeArray) ? attributeArray : null;
3676 }
3677
3678 private Name[] dfltTargetMeta;
3679 private Name[] defaultTargetMetaInfo() {
3680 if (dfltTargetMeta == null) {
3681 ArrayList<Name> defaultTargets = new ArrayList<>();
3682 defaultTargets.add(names.PACKAGE);
3683 defaultTargets.add(names.TYPE);
3684 defaultTargets.add(names.FIELD);
3685 defaultTargets.add(names.METHOD);
3686 defaultTargets.add(names.CONSTRUCTOR);
3687 defaultTargets.add(names.ANNOTATION_TYPE);
3688 defaultTargets.add(names.LOCAL_VARIABLE);
3689 defaultTargets.add(names.PARAMETER);
3690 if (allowRecords) {
3691 defaultTargets.add(names.RECORD_COMPONENT);
3692 }
3693 if (allowModules) {
3694 defaultTargets.add(names.MODULE);
3695 }
3696 dfltTargetMeta = defaultTargets.toArray(new Name[0]);
3697 }
3698 return dfltTargetMeta;
3699 }
3700
3701 /** Check an annotation value.
3702 *
3703 * @param a The annotation tree to check
3704 * @return true if this annotation tree is valid, otherwise false
3705 */
3706 public boolean validateAnnotationDeferErrors(JCAnnotation a) {
3707 boolean res = false;
3708 final Log.DiagnosticHandler diagHandler = new Log.DiscardDiagnosticHandler(log);
3709 try {
3710 res = validateAnnotation(a);
3711 } finally {
3712 log.popDiagnosticHandler(diagHandler);
3713 }
3714 return res;
3715 }
3716
3717 private boolean validateAnnotation(JCAnnotation a) {
3718 boolean isValid = true;
3719 AnnotationTypeMetadata metadata = a.annotationType.type.tsym.getAnnotationTypeMetadata();
3720
3721 // collect an inventory of the annotation elements
3722 Set<MethodSymbol> elements = metadata.getAnnotationElements();
3723
3724 // remove the ones that are assigned values
3725 for (JCTree arg : a.args) {
3726 if (!arg.hasTag(ASSIGN)) continue; // recovery
3727 JCAssign assign = (JCAssign)arg;
3728 Symbol m = TreeInfo.symbol(assign.lhs);
3729 if (m == null || m.type.isErroneous()) continue;
3730 if (!elements.remove(m)) {
3731 isValid = false;
3732 log.error(assign.lhs.pos(),
3733 Errors.DuplicateAnnotationMemberValue(m.name, a.type));
3734 }
3735 }
3736
3737 // all the remaining ones better have default values
3738 List<Name> missingDefaults = List.nil();
3739 Set<MethodSymbol> membersWithDefault = metadata.getAnnotationElementsWithDefault();
3740 for (MethodSymbol m : elements) {
3741 if (m.type.isErroneous())
3742 continue;
3743
3744 if (!membersWithDefault.contains(m))
3745 missingDefaults = missingDefaults.append(m.name);
3746 }
3747 missingDefaults = missingDefaults.reverse();
3748 if (missingDefaults.nonEmpty()) {
3749 isValid = false;
3750 Error errorKey = (missingDefaults.size() > 1)
3751 ? Errors.AnnotationMissingDefaultValue1(a.type, missingDefaults)
3752 : Errors.AnnotationMissingDefaultValue(a.type, missingDefaults);
3753 log.error(a.pos(), errorKey);
3754 }
3755
3756 return isValid && validateTargetAnnotationValue(a);
3757 }
3758
3759 /* Validate the special java.lang.annotation.Target annotation */
3760 boolean validateTargetAnnotationValue(JCAnnotation a) {
3761 // special case: java.lang.annotation.Target must not have
3762 // repeated values in its value member
3763 if (a.annotationType.type.tsym != syms.annotationTargetType.tsym ||
3764 a.args.tail == null)
3765 return true;
3766
3767 boolean isValid = true;
3768 if (!a.args.head.hasTag(ASSIGN)) return false; // error recovery
3769 JCAssign assign = (JCAssign) a.args.head;
3770 Symbol m = TreeInfo.symbol(assign.lhs);
3771 if (m.name != names.value) return false;
3772 JCTree rhs = assign.rhs;
3773 if (!rhs.hasTag(NEWARRAY)) return false;
3774 JCNewArray na = (JCNewArray) rhs;
3775 Set<Symbol> targets = new HashSet<>();
3776 for (JCTree elem : na.elems) {
3777 if (!targets.add(TreeInfo.symbol(elem))) {
3778 isValid = false;
3779 log.error(elem.pos(), Errors.RepeatedAnnotationTarget);
3780 }
3781 }
3782 return isValid;
3783 }
3784
3785 void checkDeprecatedAnnotation(DiagnosticPosition pos, Symbol s) {
3786 if (lint.isEnabled(LintCategory.DEP_ANN) && s.isDeprecatableViaAnnotation() &&
3787 (s.flags() & DEPRECATED) != 0 &&
3788 !syms.deprecatedType.isErroneous() &&
3789 s.attribute(syms.deprecatedType.tsym) == null) {
3790 log.warning(LintCategory.DEP_ANN,
3791 pos, Warnings.MissingDeprecatedAnnotation);
3792 }
3793 // Note: @Deprecated has no effect on local variables, parameters and package decls.
3794 if (lint.isEnabled(LintCategory.DEPRECATION) && !s.isDeprecatableViaAnnotation()) {
3795 if (!syms.deprecatedType.isErroneous() && s.attribute(syms.deprecatedType.tsym) != null) {
3796 log.warning(LintCategory.DEPRECATION, pos,
3797 Warnings.DeprecatedAnnotationHasNoEffect(Kinds.kindName(s)));
3798 }
3799 }
3800 }
3801
3802 void checkDeprecated(final DiagnosticPosition pos, final Symbol other, final Symbol s) {
3803 checkDeprecated(() -> pos, other, s);
3804 }
3805
3806 void checkDeprecated(Supplier<DiagnosticPosition> pos, final Symbol other, final Symbol s) {
3807 if ( (s.isDeprecatedForRemoval()
3808 || s.isDeprecated() && !other.isDeprecated())
3809 && (s.outermostClass() != other.outermostClass() || s.outermostClass() == null)
3810 && s.kind != Kind.PCK) {
3811 deferredLintHandler.report(() -> warnDeprecated(pos.get(), s));
3812 }
3813 }
3814
3815 void checkSunAPI(final DiagnosticPosition pos, final Symbol s) {
3816 if ((s.flags() & PROPRIETARY) != 0) {
3817 deferredLintHandler.report(() -> {
3818 log.mandatoryWarning(pos, Warnings.SunProprietary(s));
3819 });
3820 }
3821 }
3822
3823 void checkProfile(final DiagnosticPosition pos, final Symbol s) {
3824 if (profile != Profile.DEFAULT && (s.flags() & NOT_IN_PROFILE) != 0) {
3825 log.error(pos, Errors.NotInProfile(s, profile));
3826 }
3827 }
3828
3829 void checkPreview(DiagnosticPosition pos, Symbol other, Symbol s) {
3830 if ((s.flags() & PREVIEW_API) != 0 && !preview.participatesInPreview(syms, other, s) && !disablePreviewCheck) {
3831 if ((s.flags() & PREVIEW_REFLECTIVE) == 0) {
3832 if (!preview.isEnabled()) {
3833 log.error(pos, Errors.IsPreview(s));
3834 } else {
3835 preview.markUsesPreview(pos);
3836 deferredLintHandler.report(() -> warnPreviewAPI(pos, Warnings.IsPreview(s)));
3837 }
3838 } else {
3839 deferredLintHandler.report(() -> warnPreviewAPI(pos, Warnings.IsPreviewReflective(s)));
3840 }
3841 }
3842 if (preview.declaredUsingPreviewFeature(s)) {
3843 if (preview.isEnabled()) {
3844 //for preview disabled do presumably so not need to do anything?
3845 //If "s" is compiled from source, then there was an error for it already;
3846 //if "s" is from classfile, there already was an error for the classfile.
3847 preview.markUsesPreview(pos);
3848 deferredLintHandler.report(() -> warnDeclaredUsingPreview(pos, s));
3849 }
3850 }
3851 }
3852
3853 /* *************************************************************************
3854 * Check for recursive annotation elements.
3855 **************************************************************************/
3856
3857 /** Check for cycles in the graph of annotation elements.
3858 */
3859 void checkNonCyclicElements(JCClassDecl tree) {
3860 if ((tree.sym.flags_field & ANNOTATION) == 0) return;
3861 Assert.check((tree.sym.flags_field & LOCKED) == 0);
3862 try {
3863 tree.sym.flags_field |= LOCKED;
3864 for (JCTree def : tree.defs) {
3865 if (!def.hasTag(METHODDEF)) continue;
3866 JCMethodDecl meth = (JCMethodDecl)def;
3867 checkAnnotationResType(meth.pos(), meth.restype.type);
3868 }
3869 } finally {
3870 tree.sym.flags_field &= ~LOCKED;
3871 tree.sym.flags_field |= ACYCLIC_ANN;
3872 }
3873 }
3874
3875 void checkNonCyclicElementsInternal(DiagnosticPosition pos, TypeSymbol tsym) {
3876 if ((tsym.flags_field & ACYCLIC_ANN) != 0)
3877 return;
3878 if ((tsym.flags_field & LOCKED) != 0) {
3879 log.error(pos, Errors.CyclicAnnotationElement(tsym));
3880 return;
3881 }
3882 try {
3883 tsym.flags_field |= LOCKED;
3884 for (Symbol s : tsym.members().getSymbols(NON_RECURSIVE)) {
3885 if (s.kind != MTH)
3886 continue;
3887 checkAnnotationResType(pos, ((MethodSymbol)s).type.getReturnType());
3888 }
3889 } finally {
3890 tsym.flags_field &= ~LOCKED;
3891 tsym.flags_field |= ACYCLIC_ANN;
3892 }
3893 }
3894
3895 void checkAnnotationResType(DiagnosticPosition pos, Type type) {
3896 switch (type.getTag()) {
3897 case CLASS:
3898 if ((type.tsym.flags() & ANNOTATION) != 0)
3899 checkNonCyclicElementsInternal(pos, type.tsym);
3900 break;
3901 case ARRAY:
3902 checkAnnotationResType(pos, types.elemtype(type));
3903 break;
3904 default:
3905 break; // int etc
3906 }
3907 }
3908
3909 /* *************************************************************************
3910 * Check for cycles in the constructor call graph.
3911 **************************************************************************/
3912
3913 /** Check for cycles in the graph of constructors calling other
3914 * constructors.
3915 */
3916 void checkCyclicConstructors(JCClassDecl tree) {
3917 // use LinkedHashMap so we generate errors deterministically
3918 Map<Symbol,Symbol> callMap = new LinkedHashMap<>();
3919
3920 // enter each constructor this-call into the map
3921 for (List<JCTree> l = tree.defs; l.nonEmpty(); l = l.tail) {
3922 JCMethodInvocation app = TreeInfo.firstConstructorCall(l.head);
3923 if (app == null) continue;
3924 JCMethodDecl meth = (JCMethodDecl) l.head;
3925 if (TreeInfo.name(app.meth) == names._this) {
3926 callMap.put(meth.sym, TreeInfo.symbol(app.meth));
3927 } else {
3928 meth.sym.flags_field |= ACYCLIC;
3929 }
3930 }
3931
3932 // Check for cycles in the map
3933 Symbol[] ctors = new Symbol[0];
3934 ctors = callMap.keySet().toArray(ctors);
3935 for (Symbol caller : ctors) {
3936 checkCyclicConstructor(tree, caller, callMap);
3937 }
3938 }
3939
3940 /** Look in the map to see if the given constructor is part of a
3941 * call cycle.
3942 */
3943 private void checkCyclicConstructor(JCClassDecl tree, Symbol ctor,
3944 Map<Symbol,Symbol> callMap) {
3945 if (ctor != null && (ctor.flags_field & ACYCLIC) == 0) {
3946 if ((ctor.flags_field & LOCKED) != 0) {
3947 log.error(TreeInfo.diagnosticPositionFor(ctor, tree, false, t -> t.hasTag(IDENT)),
3948 Errors.RecursiveCtorInvocation);
3949 } else {
3950 ctor.flags_field |= LOCKED;
3951 checkCyclicConstructor(tree, callMap.remove(ctor), callMap);
3952 ctor.flags_field &= ~LOCKED;
3953 }
3954 ctor.flags_field |= ACYCLIC;
3955 }
3956 }
3957
3958 /* *************************************************************************
3959 * Miscellaneous
3960 **************************************************************************/
3961
3962 /**
3963 * Check for division by integer constant zero
3964 * @param pos Position for error reporting.
3965 * @param operator The operator for the expression
3966 * @param operand The right hand operand for the expression
3967 */
3968 void checkDivZero(final DiagnosticPosition pos, Symbol operator, Type operand) {
3969 if (operand.constValue() != null
3970 && operand.getTag().isSubRangeOf(LONG)
3971 && ((Number) (operand.constValue())).longValue() == 0) {
3972 int opc = ((OperatorSymbol)operator).opcode;
3973 if (opc == ByteCodes.idiv || opc == ByteCodes.imod
3974 || opc == ByteCodes.ldiv || opc == ByteCodes.lmod) {
3975 deferredLintHandler.report(() -> warnDivZero(pos));
3976 }
3977 }
3978 }
3979
3980 /**
3981 * Check for possible loss of precission
3982 * @param pos Position for error reporting.
3983 * @param found The computed type of the tree
3984 * @param req The computed type of the tree
3985 */
3986 void checkLossOfPrecision(final DiagnosticPosition pos, Type found, Type req) {
3987 if (found.isNumeric() && req.isNumeric() && !types.isAssignable(found, req)) {
3988 deferredLintHandler.report(() -> {
3989 if (lint.isEnabled(LintCategory.LOSSY_CONVERSIONS))
3990 log.warning(LintCategory.LOSSY_CONVERSIONS,
3991 pos, Warnings.PossibleLossOfPrecision(found, req));
3992 });
3993 }
3994 }
3995
3996 /**
3997 * Check for empty statements after if
3998 */
3999 void checkEmptyIf(JCIf tree) {
4000 if (tree.thenpart.hasTag(SKIP) && tree.elsepart == null &&
4001 lint.isEnabled(LintCategory.EMPTY))
4002 log.warning(LintCategory.EMPTY, tree.thenpart.pos(), Warnings.EmptyIf);
4003 }
4004
4005 /** Check that symbol is unique in given scope.
4006 * @param pos Position for error reporting.
4007 * @param sym The symbol.
4008 * @param s The scope.
4009 */
4010 boolean checkUnique(DiagnosticPosition pos, Symbol sym, Scope s) {
4011 if (sym.type.isErroneous())
4012 return true;
4013 if (sym.owner.name == names.any) return false;
4014 for (Symbol byName : s.getSymbolsByName(sym.name, NON_RECURSIVE)) {
4015 if (sym != byName &&
4016 (byName.flags() & CLASH) == 0 &&
4017 sym.kind == byName.kind &&
4018 sym.name != names.error &&
4019 (sym.kind != MTH ||
4020 types.hasSameArgs(sym.type, byName.type) ||
4021 types.hasSameArgs(types.erasure(sym.type), types.erasure(byName.type)))) {
4022 if ((sym.flags() & VARARGS) != (byName.flags() & VARARGS)) {
4023 sym.flags_field |= CLASH;
4024 varargsDuplicateError(pos, sym, byName);
4025 return true;
4026 } else if (sym.kind == MTH && !types.hasSameArgs(sym.type, byName.type, false)) {
4027 duplicateErasureError(pos, sym, byName);
4028 sym.flags_field |= CLASH;
4029 return true;
4030 } else if ((sym.flags() & MATCH_BINDING) != 0 &&
4031 (byName.flags() & MATCH_BINDING) != 0 &&
4032 (byName.flags() & MATCH_BINDING_TO_OUTER) == 0) {
4033 if (!sym.type.isErroneous()) {
4034 log.error(pos, Errors.MatchBindingExists);
4035 sym.flags_field |= CLASH;
4036 }
4037 return false;
4038 } else {
4039 duplicateError(pos, byName);
4040 return false;
4041 }
4042 }
4043 }
4044 return true;
4045 }
4046
4047 /** Report duplicate declaration error.
4048 */
4049 void duplicateErasureError(DiagnosticPosition pos, Symbol sym1, Symbol sym2) {
4050 if (!sym1.type.isErroneous() && !sym2.type.isErroneous()) {
4051 log.error(pos, Errors.NameClashSameErasure(sym1, sym2));
4052 }
4053 }
4054
4055 /**Check that types imported through the ordinary imports don't clash with types imported
4056 * by other (static or ordinary) imports. Note that two static imports may import two clashing
4057 * types without an error on the imports.
4058 * @param toplevel The toplevel tree for which the test should be performed.
4059 */
4060 void checkImportsUnique(JCCompilationUnit toplevel) {
4061 WriteableScope ordinallyImportedSoFar = WriteableScope.create(toplevel.packge);
4062 WriteableScope staticallyImportedSoFar = WriteableScope.create(toplevel.packge);
4063 WriteableScope topLevelScope = toplevel.toplevelScope;
4064
4065 for (JCTree def : toplevel.defs) {
4066 if (!def.hasTag(IMPORT))
4067 continue;
4068
4069 JCImport imp = (JCImport) def;
4070
4071 if (imp.importScope == null)
4072 continue;
4073
4074 for (Symbol sym : imp.importScope.getSymbols(sym -> sym.kind == TYP)) {
4075 if (imp.isStatic()) {
4076 checkUniqueImport(imp.pos(), ordinallyImportedSoFar, staticallyImportedSoFar, topLevelScope, sym, true);
4077 staticallyImportedSoFar.enter(sym);
4078 } else {
4079 checkUniqueImport(imp.pos(), ordinallyImportedSoFar, staticallyImportedSoFar, topLevelScope, sym, false);
4080 ordinallyImportedSoFar.enter(sym);
4081 }
4082 }
4083
4084 imp.importScope = null;
4085 }
4086 }
4087
4088 /** Check that single-type import is not already imported or top-level defined,
4089 * but make an exception for two single-type imports which denote the same type.
4090 * @param pos Position for error reporting.
4091 * @param ordinallyImportedSoFar A Scope containing types imported so far through
4092 * ordinary imports.
4093 * @param staticallyImportedSoFar A Scope containing types imported so far through
4094 * static imports.
4095 * @param topLevelScope The current file's top-level Scope
4096 * @param sym The symbol.
4097 * @param staticImport Whether or not this was a static import
4098 */
4099 private boolean checkUniqueImport(DiagnosticPosition pos, Scope ordinallyImportedSoFar,
4100 Scope staticallyImportedSoFar, Scope topLevelScope,
4101 Symbol sym, boolean staticImport) {
4102 Predicate<Symbol> duplicates = candidate -> candidate != sym && !candidate.type.isErroneous();
4103 Symbol ordinaryClashing = ordinallyImportedSoFar.findFirst(sym.name, duplicates);
4104 Symbol staticClashing = null;
4105 if (ordinaryClashing == null && !staticImport) {
4106 staticClashing = staticallyImportedSoFar.findFirst(sym.name, duplicates);
4107 }
4108 if (ordinaryClashing != null || staticClashing != null) {
4109 if (ordinaryClashing != null)
4110 log.error(pos, Errors.AlreadyDefinedSingleImport(ordinaryClashing));
4111 else
4112 log.error(pos, Errors.AlreadyDefinedStaticSingleImport(staticClashing));
4113 return false;
4114 }
4115 Symbol clashing = topLevelScope.findFirst(sym.name, duplicates);
4116 if (clashing != null) {
4117 log.error(pos, Errors.AlreadyDefinedThisUnit(clashing));
4118 return false;
4119 }
4120 return true;
4121 }
4122
4123 /** Check that a qualified name is in canonical form (for import decls).
4124 */
4125 public void checkCanonical(JCTree tree) {
4126 if (!isCanonical(tree))
4127 log.error(tree.pos(),
4128 Errors.ImportRequiresCanonical(TreeInfo.symbol(tree)));
4129 }
4130 // where
4131 private boolean isCanonical(JCTree tree) {
4132 while (tree.hasTag(SELECT)) {
4133 JCFieldAccess s = (JCFieldAccess) tree;
4134 if (s.sym.owner.getQualifiedName() != TreeInfo.symbol(s.selected).getQualifiedName())
4135 return false;
4136 tree = s.selected;
4137 }
4138 return true;
4139 }
4140
4141 /** Check that an auxiliary class is not accessed from any other file than its own.
4142 */
4143 void checkForBadAuxiliaryClassAccess(DiagnosticPosition pos, Env<AttrContext> env, ClassSymbol c) {
4144 if (lint.isEnabled(Lint.LintCategory.AUXILIARYCLASS) &&
4145 (c.flags() & AUXILIARY) != 0 &&
4146 rs.isAccessible(env, c) &&
4147 !fileManager.isSameFile(c.sourcefile, env.toplevel.sourcefile))
4148 {
4149 log.warning(pos,
4150 Warnings.AuxiliaryClassAccessedFromOutsideOfItsSourceFile(c, c.sourcefile));
4151 }
4152 }
4153
4154 /**
4155 * Check for a default constructor in an exported package.
4156 */
4157 void checkDefaultConstructor(ClassSymbol c, DiagnosticPosition pos) {
4158 if (lint.isEnabled(LintCategory.MISSING_EXPLICIT_CTOR) &&
4159 ((c.flags() & (ENUM | RECORD)) == 0) &&
4160 !c.isAnonymous() &&
4161 ((c.flags() & (PUBLIC | PROTECTED)) != 0) &&
4162 Feature.MODULES.allowedInSource(source)) {
4163 NestingKind nestingKind = c.getNestingKind();
4164 switch (nestingKind) {
4165 case ANONYMOUS,
4166 LOCAL -> {return;}
4167 case TOP_LEVEL -> {;} // No additional checks needed
4168 case MEMBER -> {
4169 // For nested member classes, all the enclosing
4170 // classes must be public or protected.
4171 Symbol owner = c.owner;
4172 while (owner != null && owner.kind == TYP) {
4173 if ((owner.flags() & (PUBLIC | PROTECTED)) == 0)
4174 return;
4175 owner = owner.owner;
4176 }
4177 }
4178 }
4179
4180 // Only check classes in named packages exported by its module
4181 PackageSymbol pkg = c.packge();
4182 if (!pkg.isUnnamed()) {
4183 ModuleSymbol modle = pkg.modle;
4184 for (ExportsDirective exportDir : modle.exports) {
4185 // Report warning only if the containing
4186 // package is unconditionally exported
4187 if (exportDir.packge.equals(pkg)) {
4188 if (exportDir.modules == null || exportDir.modules.isEmpty()) {
4189 // Warning may be suppressed by
4190 // annotations; check again for being
4191 // enabled in the deferred context.
4192 deferredLintHandler.report(() -> {
4193 if (lint.isEnabled(LintCategory.MISSING_EXPLICIT_CTOR))
4194 log.warning(LintCategory.MISSING_EXPLICIT_CTOR,
4195 pos, Warnings.MissingExplicitCtor(c, pkg, modle));
4196 });
4197 } else {
4198 return;
4199 }
4200 }
4201 }
4202 }
4203 }
4204 return;
4205 }
4206
4207 private class ConversionWarner extends Warner {
4208 final String uncheckedKey;
4209 final Type found;
4210 final Type expected;
4211 public ConversionWarner(DiagnosticPosition pos, String uncheckedKey, Type found, Type expected) {
4212 super(pos);
4213 this.uncheckedKey = uncheckedKey;
4214 this.found = found;
4215 this.expected = expected;
4216 }
4217
4218 @Override
4219 public void warn(LintCategory lint) {
4220 boolean warned = this.warned;
4221 super.warn(lint);
4222 if (warned) return; // suppress redundant diagnostics
4223 switch (lint) {
4224 case UNCHECKED:
4225 Check.this.warnUnchecked(pos(), Warnings.ProbFoundReq(diags.fragment(uncheckedKey), found, expected));
4226 break;
4227 case VARARGS:
4228 if (method != null &&
4229 method.attribute(syms.trustMeType.tsym) != null &&
4230 isTrustMeAllowedOnMethod(method) &&
4231 !types.isReifiable(method.type.getParameterTypes().last())) {
4232 Check.this.warnUnsafeVararg(pos(), Warnings.VarargsUnsafeUseVarargsParam(method.params.last()));
4233 }
4234 break;
4235 default:
4236 throw new AssertionError("Unexpected lint: " + lint);
4237 }
4238 }
4239 }
4240
4241 public Warner castWarner(DiagnosticPosition pos, Type found, Type expected) {
4242 return new ConversionWarner(pos, "unchecked.cast.to.type", found, expected);
4243 }
4244
4245 public Warner convertWarner(DiagnosticPosition pos, Type found, Type expected) {
4246 return new ConversionWarner(pos, "unchecked.assign", found, expected);
4247 }
4248
4249 public void checkFunctionalInterface(JCClassDecl tree, ClassSymbol cs) {
4250 Compound functionalType = cs.attribute(syms.functionalInterfaceType.tsym);
4251
4252 if (functionalType != null) {
4253 try {
4254 types.findDescriptorSymbol((TypeSymbol)cs);
4255 } catch (Types.FunctionDescriptorLookupError ex) {
4256 DiagnosticPosition pos = tree.pos();
4257 for (JCAnnotation a : tree.getModifiers().annotations) {
4258 if (a.annotationType.type.tsym == syms.functionalInterfaceType.tsym) {
4259 pos = a.pos();
4260 break;
4261 }
4262 }
4263 log.error(pos, Errors.BadFunctionalIntfAnno1(ex.getDiagnostic()));
4264 }
4265 }
4266 }
4267
4268 public void checkImportsResolvable(final JCCompilationUnit toplevel) {
4269 for (final JCImport imp : toplevel.getImports()) {
4270 if (!imp.staticImport || !imp.qualid.hasTag(SELECT))
4271 continue;
4272 final JCFieldAccess select = imp.qualid;
4273 final Symbol origin;
4274 if (select.name == names.asterisk || (origin = TreeInfo.symbol(select.selected)) == null || origin.kind != TYP)
4275 continue;
4276
4277 TypeSymbol site = (TypeSymbol) TreeInfo.symbol(select.selected);
4278 if (!checkTypeContainsImportableElement(site, site, toplevel.packge, select.name, new HashSet<Symbol>())) {
4279 log.error(imp.pos(),
4280 Errors.CantResolveLocation(KindName.STATIC,
4281 select.name,
4282 null,
4283 null,
4284 Fragments.Location(kindName(site),
4285 site,
4286 null)));
4287 }
4288 }
4289 }
4290
4291 // Check that packages imported are in scope (JLS 7.4.3, 6.3, 6.5.3.1, 6.5.3.2)
4292 public void checkImportedPackagesObservable(final JCCompilationUnit toplevel) {
4293 OUTER: for (JCImport imp : toplevel.getImports()) {
4294 if (!imp.staticImport && TreeInfo.name(imp.qualid) == names.asterisk) {
4295 TypeSymbol tsym = imp.qualid.selected.type.tsym;
4296 if (tsym.kind == PCK && tsym.members().isEmpty() &&
4297 !(Feature.IMPORT_ON_DEMAND_OBSERVABLE_PACKAGES.allowedInSource(source) && tsym.exists())) {
4298 log.error(DiagnosticFlag.RESOLVE_ERROR, imp.pos, Errors.DoesntExist(tsym));
4299 }
4300 }
4301 }
4302 }
4303
4304 private boolean checkTypeContainsImportableElement(TypeSymbol tsym, TypeSymbol origin, PackageSymbol packge, Name name, Set<Symbol> processed) {
4305 if (tsym == null || !processed.add(tsym))
4306 return false;
4307
4308 // also search through inherited names
4309 if (checkTypeContainsImportableElement(types.supertype(tsym.type).tsym, origin, packge, name, processed))
4310 return true;
4311
4312 for (Type t : types.interfaces(tsym.type))
4313 if (checkTypeContainsImportableElement(t.tsym, origin, packge, name, processed))
4314 return true;
4315
4316 for (Symbol sym : tsym.members().getSymbolsByName(name)) {
4317 if (sym.isStatic() &&
4318 importAccessible(sym, packge) &&
4319 sym.isMemberOf(origin, types)) {
4320 return true;
4321 }
4322 }
4323
4324 return false;
4325 }
4326
4327 // is the sym accessible everywhere in packge?
4328 public boolean importAccessible(Symbol sym, PackageSymbol packge) {
4329 try {
4330 int flags = (int)(sym.flags() & AccessFlags);
4331 switch (flags) {
4332 default:
4333 case PUBLIC:
4334 return true;
4335 case PRIVATE:
4336 return false;
4337 case 0:
4338 case PROTECTED:
4339 return sym.packge() == packge;
4340 }
4341 } catch (ClassFinder.BadClassFile err) {
4342 throw err;
4343 } catch (CompletionFailure ex) {
4344 return false;
4345 }
4346 }
4347
4348 public Type checkProcessorType(JCExpression processor, Type resultType, Env<AttrContext> env) {
4349 Type processorType = processor.type;
4350 Type interfaceType = types.asSuper(processorType, syms.processorType.tsym);
4351
4352 if (interfaceType != null) {
4353 List<Type> typeArguments = interfaceType.getTypeArguments();
4354
4355 if (typeArguments.size() == 2) {
4356 resultType = typeArguments.head;
4357 } else {
4358 log.error(DiagnosticFlag.RESOLVE_ERROR, processor.pos,
4359 Errors.ProcessorTypeCannotBeARawType(processorType.tsym));
4360 }
4361 } else {
4362 log.error(DiagnosticFlag.RESOLVE_ERROR, processor.pos,
4363 Errors.NotAProcessorType(processorType.tsym));
4364 }
4365
4366 return resultType;
4367 }
4368
4369 public void checkLeaksNotAccessible(Env<AttrContext> env, JCClassDecl check) {
4370 JCCompilationUnit toplevel = env.toplevel;
4371
4372 if ( toplevel.modle == syms.unnamedModule
4373 || toplevel.modle == syms.noModule
4374 || (check.sym.flags() & COMPOUND) != 0) {
4375 return ;
4376 }
4377
4378 ExportsDirective currentExport = findExport(toplevel.packge);
4379
4380 if ( currentExport == null //not exported
4381 || currentExport.modules != null) //don't check classes in qualified export
4382 return ;
4383
4384 new TreeScanner() {
4385 Lint lint = env.info.lint;
4386 boolean inSuperType;
4387
4388 @Override
4389 public void visitBlock(JCBlock tree) {
4390 }
4391 @Override
4392 public void visitMethodDef(JCMethodDecl tree) {
4393 if (!isAPISymbol(tree.sym))
4394 return;
4395 Lint prevLint = lint;
4396 try {
4397 lint = lint.augment(tree.sym);
4398 if (lint.isEnabled(LintCategory.EXPORTS)) {
4399 super.visitMethodDef(tree);
4400 }
4401 } finally {
4402 lint = prevLint;
4403 }
4404 }
4405 @Override
4406 public void visitVarDef(JCVariableDecl tree) {
4407 if (!isAPISymbol(tree.sym) && tree.sym.owner.kind != MTH)
4408 return;
4409 Lint prevLint = lint;
4410 try {
4411 lint = lint.augment(tree.sym);
4412 if (lint.isEnabled(LintCategory.EXPORTS)) {
4413 scan(tree.mods);
4414 scan(tree.vartype);
4415 }
4416 } finally {
4417 lint = prevLint;
4418 }
4419 }
4420 @Override
4421 public void visitClassDef(JCClassDecl tree) {
4422 if (tree != check)
4423 return ;
4424
4425 if (!isAPISymbol(tree.sym))
4426 return ;
4427
4428 Lint prevLint = lint;
4429 try {
4430 lint = lint.augment(tree.sym);
4431 if (lint.isEnabled(LintCategory.EXPORTS)) {
4432 scan(tree.mods);
4433 scan(tree.typarams);
4434 try {
4435 inSuperType = true;
4436 scan(tree.extending);
4437 scan(tree.implementing);
4438 } finally {
4439 inSuperType = false;
4440 }
4441 scan(tree.defs);
4442 }
4443 } finally {
4444 lint = prevLint;
4445 }
4446 }
4447 @Override
4448 public void visitTypeApply(JCTypeApply tree) {
4449 scan(tree.clazz);
4450 boolean oldInSuperType = inSuperType;
4451 try {
4452 inSuperType = false;
4453 scan(tree.arguments);
4454 } finally {
4455 inSuperType = oldInSuperType;
4456 }
4457 }
4458 @Override
4459 public void visitIdent(JCIdent tree) {
4460 Symbol sym = TreeInfo.symbol(tree);
4461 if (sym.kind == TYP && !sym.type.hasTag(TYPEVAR)) {
4462 checkVisible(tree.pos(), sym, toplevel.packge, inSuperType);
4463 }
4464 }
4465
4466 @Override
4467 public void visitSelect(JCFieldAccess tree) {
4468 Symbol sym = TreeInfo.symbol(tree);
4469 Symbol sitesym = TreeInfo.symbol(tree.selected);
4470 if (sym.kind == TYP && sitesym.kind == PCK) {
4471 checkVisible(tree.pos(), sym, toplevel.packge, inSuperType);
4472 } else {
4473 super.visitSelect(tree);
4474 }
4475 }
4476
4477 @Override
4478 public void visitAnnotation(JCAnnotation tree) {
4479 if (tree.attribute.type.tsym.getAnnotation(java.lang.annotation.Documented.class) != null)
4480 super.visitAnnotation(tree);
4481 }
4482
4483 }.scan(check);
4484 }
4485 //where:
4486 private ExportsDirective findExport(PackageSymbol pack) {
4487 for (ExportsDirective d : pack.modle.exports) {
4488 if (d.packge == pack)
4489 return d;
4490 }
4491
4492 return null;
4493 }
4494 private boolean isAPISymbol(Symbol sym) {
4495 while (sym.kind != PCK) {
4496 if ((sym.flags() & Flags.PUBLIC) == 0 && (sym.flags() & Flags.PROTECTED) == 0) {
4497 return false;
4498 }
4499 sym = sym.owner;
4500 }
4501 return true;
4502 }
4503 private void checkVisible(DiagnosticPosition pos, Symbol what, PackageSymbol inPackage, boolean inSuperType) {
4504 if (!isAPISymbol(what) && !inSuperType) { //package private/private element
4505 log.warning(LintCategory.EXPORTS, pos, Warnings.LeaksNotAccessible(kindName(what), what, what.packge().modle));
4506 return ;
4507 }
4508
4509 PackageSymbol whatPackage = what.packge();
4510 ExportsDirective whatExport = findExport(whatPackage);
4511 ExportsDirective inExport = findExport(inPackage);
4512
4513 if (whatExport == null) { //package not exported:
4514 log.warning(LintCategory.EXPORTS, pos, Warnings.LeaksNotAccessibleUnexported(kindName(what), what, what.packge().modle));
4515 return ;
4516 }
4517
4518 if (whatExport.modules != null) {
4519 if (inExport.modules == null || !whatExport.modules.containsAll(inExport.modules)) {
4520 log.warning(LintCategory.EXPORTS, pos, Warnings.LeaksNotAccessibleUnexportedQualified(kindName(what), what, what.packge().modle));
4521 }
4522 }
4523
4524 if (whatPackage.modle != inPackage.modle && whatPackage.modle != syms.java_base) {
4525 //check that relativeTo.modle requires transitive what.modle, somehow:
4526 List<ModuleSymbol> todo = List.of(inPackage.modle);
4527
4528 while (todo.nonEmpty()) {
4529 ModuleSymbol current = todo.head;
4530 todo = todo.tail;
4531 if (current == whatPackage.modle)
4532 return ; //OK
4533 if ((current.flags() & Flags.AUTOMATIC_MODULE) != 0)
4534 continue; //for automatic modules, don't look into their dependencies
4535 for (RequiresDirective req : current.requires) {
4536 if (req.isTransitive()) {
4537 todo = todo.prepend(req.module);
4538 }
4539 }
4540 }
4541
4542 log.warning(LintCategory.EXPORTS, pos, Warnings.LeaksNotAccessibleNotRequiredTransitive(kindName(what), what, what.packge().modle));
4543 }
4544 }
4545
4546 void checkModuleExists(final DiagnosticPosition pos, ModuleSymbol msym) {
4547 if (msym.kind != MDL) {
4548 deferredLintHandler.report(() -> {
4549 if (lint.isEnabled(LintCategory.MODULE))
4550 log.warning(LintCategory.MODULE, pos, Warnings.ModuleNotFound(msym));
4551 });
4552 }
4553 }
4554
4555 void checkPackageExistsForOpens(final DiagnosticPosition pos, PackageSymbol packge) {
4556 if (packge.members().isEmpty() &&
4557 ((packge.flags() & Flags.HAS_RESOURCE) == 0)) {
4558 deferredLintHandler.report(() -> {
4559 if (lint.isEnabled(LintCategory.OPENS))
4560 log.warning(pos, Warnings.PackageEmptyOrNotFound(packge));
4561 });
4562 }
4563 }
4564
4565 void checkModuleRequires(final DiagnosticPosition pos, final RequiresDirective rd) {
4566 if ((rd.module.flags() & Flags.AUTOMATIC_MODULE) != 0) {
4567 deferredLintHandler.report(() -> {
4568 if (rd.isTransitive() && lint.isEnabled(LintCategory.REQUIRES_TRANSITIVE_AUTOMATIC)) {
4569 log.warning(pos, Warnings.RequiresTransitiveAutomatic);
4570 } else if (lint.isEnabled(LintCategory.REQUIRES_AUTOMATIC)) {
4571 log.warning(pos, Warnings.RequiresAutomatic);
4572 }
4573 });
4574 }
4575 }
4576
4577 /**
4578 * Verify the case labels conform to the constraints. Checks constraints related
4579 * combinations of patterns and other labels.
4580 *
4581 * @param cases the cases that should be checked.
4582 */
4583 void checkSwitchCaseStructure(List<JCCase> cases) {
4584 for (List<JCCase> l = cases; l.nonEmpty(); l = l.tail) {
4585 JCCase c = l.head;
4586 if (c.labels.head instanceof JCConstantCaseLabel constLabel) {
4587 if (TreeInfo.isNull(constLabel.expr)) {
4588 if (c.labels.tail.nonEmpty()) {
4589 if (c.labels.tail.head instanceof JCDefaultCaseLabel defLabel) {
4590 if (c.labels.tail.tail.nonEmpty()) {
4591 log.error(c.labels.tail.tail.head.pos(), Errors.InvalidCaseLabelCombination);
4592 }
4593 } else {
4594 log.error(c.labels.tail.head.pos(), Errors.InvalidCaseLabelCombination);
4595 }
4596 }
4597 } else {
4598 for (JCCaseLabel label : c.labels.tail) {
4599 if (!(label instanceof JCConstantCaseLabel) || TreeInfo.isNullCaseLabel(label)) {
4600 log.error(label.pos(), Errors.InvalidCaseLabelCombination);
4601 break;
4602 }
4603 }
4604 }
4605 } else if (c.labels.tail.nonEmpty()) {
4606 var patterCaseLabels = c.labels.stream().filter(ll -> ll instanceof JCPatternCaseLabel).map(cl -> (JCPatternCaseLabel)cl);
4607 var allUnderscore = patterCaseLabels.allMatch(pcl -> !hasBindings(pcl.getPattern()));
4608
4609 if (!allUnderscore) {
4610 log.error(c.labels.tail.head.pos(), Errors.FlowsThroughFromPattern);
4611 }
4612
4613 boolean allPatternCaseLabels = c.labels.stream().allMatch(p -> p instanceof JCPatternCaseLabel);
4614
4615 if (allPatternCaseLabels) {
4616 preview.checkSourceLevel(c.labels.tail.head.pos(), Feature.UNNAMED_VARIABLES);
4617 }
4618
4619 for (JCCaseLabel label : c.labels.tail) {
4620 if (label instanceof JCConstantCaseLabel) {
4621 log.error(label.pos(), Errors.InvalidCaseLabelCombination);
4622 break;
4623 }
4624 }
4625 }
4626 }
4627
4628 boolean isCaseStatementGroup = cases.nonEmpty() &&
4629 cases.head.caseKind == CaseTree.CaseKind.STATEMENT;
4630
4631 if (isCaseStatementGroup) {
4632 boolean previousCompletessNormally = false;
4633 for (List<JCCase> l = cases; l.nonEmpty(); l = l.tail) {
4634 JCCase c = l.head;
4635 if (previousCompletessNormally &&
4636 c.stats.nonEmpty() &&
4637 c.labels.head instanceof JCPatternCaseLabel patternLabel &&
4638 hasBindings(patternLabel.pat)) {
4639 log.error(c.labels.head.pos(), Errors.FlowsThroughToPattern);
4640 } else if (c.stats.isEmpty() &&
4641 c.labels.head instanceof JCPatternCaseLabel patternLabel &&
4642 hasBindings(patternLabel.pat) &&
4643 hasStatements(l.tail)) {
4644 log.error(c.labels.head.pos(), Errors.FlowsThroughFromPattern);
4645 }
4646 previousCompletessNormally = c.completesNormally;
4647 }
4648 }
4649 }
4650
4651 boolean hasBindings(JCPattern p) {
4652 boolean[] bindings = new boolean[1];
4653
4654 new TreeScanner() {
4655 @Override
4656 public void visitBindingPattern(JCBindingPattern tree) {
4657 bindings[0] = !tree.var.sym.isUnnamedVariable();
4658 super.visitBindingPattern(tree);
4659 }
4660 }.scan(p);
4661
4662 return bindings[0];
4663 }
4664
4665 boolean hasStatements(List<JCCase> cases) {
4666 for (List<JCCase> l = cases; l.nonEmpty(); l = l.tail) {
4667 if (l.head.stats.nonEmpty()) {
4668 return true;
4669 }
4670 }
4671
4672 return false;
4673 }
4674 void checkSwitchCaseLabelDominated(List<JCCase> cases) {
4675 List<Pair<JCCase, JCCaseLabel>> caseLabels = List.nil();
4676 boolean seenDefault = false;
4677 boolean seenDefaultLabel = false;
4678 boolean warnDominatedByDefault = false;
4679 for (List<JCCase> l = cases; l.nonEmpty(); l = l.tail) {
4680 JCCase c = l.head;
4681 for (JCCaseLabel label : c.labels) {
4682 if (label.hasTag(DEFAULTCASELABEL)) {
4683 seenDefault = true;
4684 seenDefaultLabel |=
4685 TreeInfo.isNullCaseLabel(c.labels.head);
4686 continue;
4687 }
4688 if (TreeInfo.isNullCaseLabel(label)) {
4689 if (seenDefault) {
4690 log.error(label.pos(), Errors.PatternDominated);
4691 }
4692 continue;
4693 }
4694 if (seenDefault && !warnDominatedByDefault) {
4695 if (label.hasTag(PATTERNCASELABEL) ||
4696 (label instanceof JCConstantCaseLabel && seenDefaultLabel)) {
4697 log.error(label.pos(), Errors.PatternDominated);
4698 warnDominatedByDefault = true;
4699 }
4700 }
4701 Type currentType = labelType(label);
4702 for (Pair<JCCase, JCCaseLabel> caseAndLabel : caseLabels) {
4703 JCCase testCase = caseAndLabel.fst;
4704 JCCaseLabel testCaseLabel = caseAndLabel.snd;
4705 Type testType = labelType(testCaseLabel);
4706 if (types.isSubtype(currentType, testType) &&
4707 !currentType.hasTag(ERROR) && !testType.hasTag(ERROR)) {
4708 //the current label is potentially dominated by the existing (test) label, check:
4709 boolean dominated = false;
4710 if (label instanceof JCConstantCaseLabel) {
4711 dominated |= !(testCaseLabel instanceof JCConstantCaseLabel) &&
4712 TreeInfo.unguardedCase(testCase);
4713 } else if (label instanceof JCPatternCaseLabel patternCL &&
4714 testCaseLabel instanceof JCPatternCaseLabel testPatternCaseLabel &&
4715 (testCase.equals(c) || TreeInfo.unguardedCase(testCase))) {
4716 dominated = patternDominated(testPatternCaseLabel.pat,
4717 patternCL.pat);
4718 }
4719 if (dominated) {
4720 log.error(label.pos(), Errors.PatternDominated);
4721 }
4722 }
4723 }
4724 caseLabels = caseLabels.prepend(Pair.of(c, label));
4725 }
4726 }
4727 }
4728 //where:
4729 private Type labelType(JCCaseLabel label) {
4730 return types.erasure(switch (label.getTag()) {
4731 case PATTERNCASELABEL -> ((JCPatternCaseLabel) label).pat.type;
4732 case CONSTANTCASELABEL -> types.boxedTypeOrType(((JCConstantCaseLabel) label).expr.type);
4733 default -> throw Assert.error("Unexpected tree kind: " + label.getTag());
4734 });
4735 }
4736 private boolean patternDominated(JCPattern existingPattern, JCPattern currentPattern) {
4737 Type existingPatternType = types.erasure(existingPattern.type);
4738 Type currentPatternType = types.erasure(currentPattern.type);
4739 if (existingPatternType.isPrimitive() ^ currentPatternType.isPrimitive()) {
4740 return false;
4741 }
4742 if (existingPatternType.isPrimitive()) {
4743 return types.isSameType(existingPatternType, currentPatternType);
4744 } else {
4745 if (!types.isSubtype(currentPatternType, existingPatternType)) {
4746 return false;
4747 }
4748 }
4749 if (currentPattern instanceof JCBindingPattern ||
4750 currentPattern instanceof JCAnyPattern) {
4751 return existingPattern instanceof JCBindingPattern ||
4752 existingPattern instanceof JCAnyPattern;
4753 } else if (currentPattern instanceof JCRecordPattern currentRecordPattern) {
4754 if (existingPattern instanceof JCBindingPattern ||
4755 existingPattern instanceof JCAnyPattern) {
4756 return true;
4757 } else if (existingPattern instanceof JCRecordPattern existingRecordPattern) {
4758 List<JCPattern> existingNested = existingRecordPattern.nested;
4759 List<JCPattern> currentNested = currentRecordPattern.nested;
4760 if (existingNested.size() != currentNested.size()) {
4761 return false;
4762 }
4763 while (existingNested.nonEmpty()) {
4764 if (!patternDominated(existingNested.head, currentNested.head)) {
4765 return false;
4766 }
4767 existingNested = existingNested.tail;
4768 currentNested = currentNested.tail;
4769 }
4770 return true;
4771 } else {
4772 Assert.error("Unknown pattern: " + existingPattern.getTag());
4773 }
4774 } else {
4775 Assert.error("Unknown pattern: " + currentPattern.getTag());
4776 }
4777 return false;
4778 }
4779
4780 /** check if a type is a subtype of Externalizable, if that is available. */
4781 boolean isExternalizable(Type t) {
4782 try {
4783 syms.externalizableType.complete();
4784 } catch (CompletionFailure e) {
4785 return false;
4786 }
4787 return types.isSubtype(t, syms.externalizableType);
4788 }
4789
4790 /**
4791 * Check structure of serialization declarations.
4792 */
4793 public void checkSerialStructure(JCClassDecl tree, ClassSymbol c) {
4794 (new SerialTypeVisitor()).visit(c, tree);
4795 }
4796
4797 /**
4798 * This visitor will warn if a serialization-related field or
4799 * method is declared in a suspicious or incorrect way. In
4800 * particular, it will warn for cases where the runtime
4801 * serialization mechanism will silently ignore a mis-declared
4802 * entity.
4803 *
4804 * Distinguished serialization-related fields and methods:
4805 *
4806 * Methods:
4807 *
4808 * private void writeObject(ObjectOutputStream stream) throws IOException
4809 * ANY-ACCESS-MODIFIER Object writeReplace() throws ObjectStreamException
4810 *
4811 * private void readObject(ObjectInputStream stream) throws IOException, ClassNotFoundException
4812 * private void readObjectNoData() throws ObjectStreamException
4813 * ANY-ACCESS-MODIFIER Object readResolve() throws ObjectStreamException
4814 *
4815 * Fields:
4816 *
4817 * private static final long serialVersionUID
4818 * private static final ObjectStreamField[] serialPersistentFields
4819 *
4820 * Externalizable: methods defined on the interface
4821 * public void writeExternal(ObjectOutput) throws IOException
4822 * public void readExternal(ObjectInput) throws IOException
4823 */
4824 private class SerialTypeVisitor extends ElementKindVisitor14<Void, JCClassDecl> {
4825 SerialTypeVisitor() {
4826 this.lint = Check.this.lint;
4827 }
4828
4829 private static final Set<String> serialMethodNames =
4830 Set.of("writeObject", "writeReplace",
4831 "readObject", "readObjectNoData",
4832 "readResolve");
4833
4834 private static final Set<String> serialFieldNames =
4835 Set.of("serialVersionUID", "serialPersistentFields");
4836
4837 // Type of serialPersistentFields
4838 private final Type OSF_TYPE = new Type.ArrayType(syms.objectStreamFieldType, syms.arrayClass);
4839
4840 Lint lint;
4841
4842 @Override
4843 public Void defaultAction(Element e, JCClassDecl p) {
4844 throw new IllegalArgumentException(Objects.requireNonNullElse(e.toString(), ""));
4845 }
4846
4847 @Override
4848 public Void visitType(TypeElement e, JCClassDecl p) {
4849 runUnderLint(e, p, (symbol, param) -> super.visitType(symbol, param));
4850 return null;
4851 }
4852
4853 @Override
4854 public Void visitTypeAsClass(TypeElement e,
4855 JCClassDecl p) {
4856 // Anonymous classes filtered out by caller.
4857
4858 ClassSymbol c = (ClassSymbol)e;
4859
4860 checkCtorAccess(p, c);
4861
4862 // Check for missing serialVersionUID; check *not* done
4863 // for enums or records.
4864 VarSymbol svuidSym = null;
4865 for (Symbol sym : c.members().getSymbolsByName(names.serialVersionUID)) {
4866 if (sym.kind == VAR) {
4867 svuidSym = (VarSymbol)sym;
4868 break;
4869 }
4870 }
4871
4872 if (svuidSym == null) {
4873 log.warning(LintCategory.SERIAL, p.pos(), Warnings.MissingSVUID(c));
4874 }
4875
4876 // Check for serialPersistentFields to gate checks for
4877 // non-serializable non-transient instance fields
4878 boolean serialPersistentFieldsPresent =
4879 c.members()
4880 .getSymbolsByName(names.serialPersistentFields, sym -> sym.kind == VAR)
4881 .iterator()
4882 .hasNext();
4883
4884 // Check declarations of serialization-related methods and
4885 // fields
4886 for(Symbol el : c.getEnclosedElements()) {
4887 runUnderLint(el, p, (enclosed, tree) -> {
4888 String name = null;
4889 switch(enclosed.getKind()) {
4890 case FIELD -> {
4891 if (!serialPersistentFieldsPresent) {
4892 var flags = enclosed.flags();
4893 if ( ((flags & TRANSIENT) == 0) &&
4894 ((flags & STATIC) == 0)) {
4895 Type varType = enclosed.asType();
4896 if (!canBeSerialized(varType)) {
4897 // Note per JLS arrays are
4898 // serializable even if the
4899 // component type is not.
4900 log.warning(LintCategory.SERIAL,
4901 TreeInfo.diagnosticPositionFor(enclosed, tree),
4902 Warnings.NonSerializableInstanceField);
4903 } else if (varType.hasTag(ARRAY)) {
4904 ArrayType arrayType = (ArrayType)varType;
4905 Type elementType = arrayType.elemtype;
4906 while (elementType.hasTag(ARRAY)) {
4907 arrayType = (ArrayType)elementType;
4908 elementType = arrayType.elemtype;
4909 }
4910 if (!canBeSerialized(elementType)) {
4911 log.warning(LintCategory.SERIAL,
4912 TreeInfo.diagnosticPositionFor(enclosed, tree),
4913 Warnings.NonSerializableInstanceFieldArray(elementType));
4914 }
4915 }
4916 }
4917 }
4918
4919 name = enclosed.getSimpleName().toString();
4920 if (serialFieldNames.contains(name)) {
4921 VarSymbol field = (VarSymbol)enclosed;
4922 switch (name) {
4923 case "serialVersionUID" -> checkSerialVersionUID(tree, e, field);
4924 case "serialPersistentFields" -> checkSerialPersistentFields(tree, e, field);
4925 default -> throw new AssertionError();
4926 }
4927 }
4928 }
4929
4930 // Correctly checking the serialization-related
4931 // methods is subtle. For the methods declared to be
4932 // private or directly declared in the class, the
4933 // enclosed elements of the class can be checked in
4934 // turn. However, writeReplace and readResolve can be
4935 // declared in a superclass and inherited. Note that
4936 // the runtime lookup walks the superclass chain
4937 // looking for writeReplace/readResolve via
4938 // Class.getDeclaredMethod. This differs from calling
4939 // Elements.getAllMembers(TypeElement) as the latter
4940 // will also pull in default methods from
4941 // superinterfaces. In other words, the runtime checks
4942 // (which long predate default methods on interfaces)
4943 // do not admit the possibility of inheriting methods
4944 // this way, a difference from general inheritance.
4945
4946 // The current implementation just checks the enclosed
4947 // elements and does not directly check the inherited
4948 // methods. If all the types are being checked this is
4949 // less of a concern; however, there are cases that
4950 // could be missed. In particular, readResolve and
4951 // writeReplace could, in principle, by inherited from
4952 // a non-serializable superclass and thus not checked
4953 // even if compiled with a serializable child class.
4954 case METHOD -> {
4955 var method = (MethodSymbol)enclosed;
4956 name = method.getSimpleName().toString();
4957 if (serialMethodNames.contains(name)) {
4958 switch (name) {
4959 case "writeObject" -> checkWriteObject(tree, e, method);
4960 case "writeReplace" -> checkWriteReplace(tree,e, method);
4961 case "readObject" -> checkReadObject(tree,e, method);
4962 case "readObjectNoData" -> checkReadObjectNoData(tree, e, method);
4963 case "readResolve" -> checkReadResolve(tree, e, method);
4964 default -> throw new AssertionError();
4965 }
4966 }
4967 }
4968 }
4969 });
4970 }
4971
4972 return null;
4973 }
4974
4975 boolean canBeSerialized(Type type) {
4976 return type.isPrimitive() || rs.isSerializable(type);
4977 }
4978
4979 /**
4980 * Check that Externalizable class needs a public no-arg
4981 * constructor.
4982 *
4983 * Check that a Serializable class has access to the no-arg
4984 * constructor of its first nonserializable superclass.
4985 */
4986 private void checkCtorAccess(JCClassDecl tree, ClassSymbol c) {
4987 if (isExternalizable(c.type)) {
4988 for(var sym : c.getEnclosedElements()) {
4989 if (sym.isConstructor() &&
4990 ((sym.flags() & PUBLIC) == PUBLIC)) {
4991 if (((MethodSymbol)sym).getParameters().isEmpty()) {
4992 return;
4993 }
4994 }
4995 }
4996 log.warning(LintCategory.SERIAL, tree.pos(),
4997 Warnings.ExternalizableMissingPublicNoArgCtor);
4998 } else {
4999 // Approximate access to the no-arg constructor up in
5000 // the superclass chain by checking that the
5001 // constructor is not private. This may not handle
5002 // some cross-package situations correctly.
5003 Type superClass = c.getSuperclass();
5004 // java.lang.Object is *not* Serializable so this loop
5005 // should terminate.
5006 while (rs.isSerializable(superClass) ) {
5007 try {
5008 superClass = (Type)((TypeElement)(((DeclaredType)superClass)).asElement()).getSuperclass();
5009 } catch(ClassCastException cce) {
5010 return ; // Don't try to recover
5011 }
5012 }
5013 // Non-Serializable superclass
5014 try {
5015 ClassSymbol supertype = ((ClassSymbol)(((DeclaredType)superClass).asElement()));
5016 for(var sym : supertype.getEnclosedElements()) {
5017 if (sym.isConstructor()) {
5018 MethodSymbol ctor = (MethodSymbol)sym;
5019 if (ctor.getParameters().isEmpty()) {
5020 if (((ctor.flags() & PRIVATE) == PRIVATE) ||
5021 // Handle nested classes and implicit this$0
5022 (supertype.getNestingKind() == NestingKind.MEMBER &&
5023 ((supertype.flags() & STATIC) == 0)))
5024 log.warning(LintCategory.SERIAL, tree.pos(),
5025 Warnings.SerializableMissingAccessNoArgCtor(supertype.getQualifiedName()));
5026 }
5027 }
5028 }
5029 } catch (ClassCastException cce) {
5030 return ; // Don't try to recover
5031 }
5032 return;
5033 }
5034 }
5035
5036 private void checkSerialVersionUID(JCClassDecl tree, Element e, VarSymbol svuid) {
5037 // To be effective, serialVersionUID must be marked static
5038 // and final, but private is recommended. But alas, in
5039 // practice there are many non-private serialVersionUID
5040 // fields.
5041 if ((svuid.flags() & (STATIC | FINAL)) !=
5042 (STATIC | FINAL)) {
5043 log.warning(LintCategory.SERIAL,
5044 TreeInfo.diagnosticPositionFor(svuid, tree),
5045 Warnings.ImproperSVUID((Symbol)e));
5046 }
5047
5048 // check svuid has type long
5049 if (!svuid.type.hasTag(LONG)) {
5050 log.warning(LintCategory.SERIAL,
5051 TreeInfo.diagnosticPositionFor(svuid, tree),
5052 Warnings.LongSVUID((Symbol)e));
5053 }
5054
5055 if (svuid.getConstValue() == null)
5056 log.warning(LintCategory.SERIAL,
5057 TreeInfo.diagnosticPositionFor(svuid, tree),
5058 Warnings.ConstantSVUID((Symbol)e));
5059 }
5060
5061 private void checkSerialPersistentFields(JCClassDecl tree, Element e, VarSymbol spf) {
5062 // To be effective, serialPersisentFields must be private, static, and final.
5063 if ((spf.flags() & (PRIVATE | STATIC | FINAL)) !=
5064 (PRIVATE | STATIC | FINAL)) {
5065 log.warning(LintCategory.SERIAL,
5066 TreeInfo.diagnosticPositionFor(spf, tree),
5067 Warnings.ImproperSPF);
5068 }
5069
5070 if (!types.isSameType(spf.type, OSF_TYPE)) {
5071 log.warning(LintCategory.SERIAL,
5072 TreeInfo.diagnosticPositionFor(spf, tree),
5073 Warnings.OSFArraySPF);
5074 }
5075
5076 if (isExternalizable((Type)(e.asType()))) {
5077 log.warning(LintCategory.SERIAL,
5078 TreeInfo.diagnosticPositionFor(spf, tree),
5079 Warnings.IneffectualSerialFieldExternalizable);
5080 }
5081
5082 // Warn if serialPersistentFields is initialized to a
5083 // literal null.
5084 JCTree spfDecl = TreeInfo.declarationFor(spf, tree);
5085 if (spfDecl != null && spfDecl.getTag() == VARDEF) {
5086 JCVariableDecl variableDef = (JCVariableDecl) spfDecl;
5087 JCExpression initExpr = variableDef.init;
5088 if (initExpr != null && TreeInfo.isNull(initExpr)) {
5089 log.warning(LintCategory.SERIAL, initExpr.pos(),
5090 Warnings.SPFNullInit);
5091 }
5092 }
5093 }
5094
5095 private void checkWriteObject(JCClassDecl tree, Element e, MethodSymbol method) {
5096 // The "synchronized" modifier is seen in the wild on
5097 // readObject and writeObject methods and is generally
5098 // innocuous.
5099
5100 // private void writeObject(ObjectOutputStream stream) throws IOException
5101 checkPrivateNonStaticMethod(tree, method);
5102 checkReturnType(tree, e, method, syms.voidType);
5103 checkOneArg(tree, e, method, syms.objectOutputStreamType);
5104 checkExceptions(tree, e, method, syms.ioExceptionType);
5105 checkExternalizable(tree, e, method);
5106 }
5107
5108 private void checkWriteReplace(JCClassDecl tree, Element e, MethodSymbol method) {
5109 // ANY-ACCESS-MODIFIER Object writeReplace() throws
5110 // ObjectStreamException
5111
5112 // Excluding abstract, could have a more complicated
5113 // rule based on abstract-ness of the class
5114 checkConcreteInstanceMethod(tree, e, method);
5115 checkReturnType(tree, e, method, syms.objectType);
5116 checkNoArgs(tree, e, method);
5117 checkExceptions(tree, e, method, syms.objectStreamExceptionType);
5118 }
5119
5120 private void checkReadObject(JCClassDecl tree, Element e, MethodSymbol method) {
5121 // The "synchronized" modifier is seen in the wild on
5122 // readObject and writeObject methods and is generally
5123 // innocuous.
5124
5125 // private void readObject(ObjectInputStream stream)
5126 // throws IOException, ClassNotFoundException
5127 checkPrivateNonStaticMethod(tree, method);
5128 checkReturnType(tree, e, method, syms.voidType);
5129 checkOneArg(tree, e, method, syms.objectInputStreamType);
5130 checkExceptions(tree, e, method, syms.ioExceptionType, syms.classNotFoundExceptionType);
5131 checkExternalizable(tree, e, method);
5132 }
5133
5134 private void checkReadObjectNoData(JCClassDecl tree, Element e, MethodSymbol method) {
5135 // private void readObjectNoData() throws ObjectStreamException
5136 checkPrivateNonStaticMethod(tree, method);
5137 checkReturnType(tree, e, method, syms.voidType);
5138 checkNoArgs(tree, e, method);
5139 checkExceptions(tree, e, method, syms.objectStreamExceptionType);
5140 checkExternalizable(tree, e, method);
5141 }
5142
5143 private void checkReadResolve(JCClassDecl tree, Element e, MethodSymbol method) {
5144 // ANY-ACCESS-MODIFIER Object readResolve()
5145 // throws ObjectStreamException
5146
5147 // Excluding abstract, could have a more complicated
5148 // rule based on abstract-ness of the class
5149 checkConcreteInstanceMethod(tree, e, method);
5150 checkReturnType(tree,e, method, syms.objectType);
5151 checkNoArgs(tree, e, method);
5152 checkExceptions(tree, e, method, syms.objectStreamExceptionType);
5153 }
5154
5155 private void checkWriteExternalRecord(JCClassDecl tree, Element e, MethodSymbol method, boolean isExtern) {
5156 //public void writeExternal(ObjectOutput) throws IOException
5157 checkExternMethodRecord(tree, e, method, syms.objectOutputType, isExtern);
5158 }
5159
5160 private void checkReadExternalRecord(JCClassDecl tree, Element e, MethodSymbol method, boolean isExtern) {
5161 // public void readExternal(ObjectInput) throws IOException
5162 checkExternMethodRecord(tree, e, method, syms.objectInputType, isExtern);
5163 }
5164
5165 private void checkExternMethodRecord(JCClassDecl tree, Element e, MethodSymbol method, Type argType,
5166 boolean isExtern) {
5167 if (isExtern && isExternMethod(tree, e, method, argType)) {
5168 log.warning(LintCategory.SERIAL,
5169 TreeInfo.diagnosticPositionFor(method, tree),
5170 Warnings.IneffectualExternalizableMethodRecord(method.getSimpleName().toString()));
5171 }
5172 }
5173
5174 void checkPrivateNonStaticMethod(JCClassDecl tree, MethodSymbol method) {
5175 var flags = method.flags();
5176 if ((flags & PRIVATE) == 0) {
5177 log.warning(LintCategory.SERIAL,
5178 TreeInfo.diagnosticPositionFor(method, tree),
5179 Warnings.SerialMethodNotPrivate(method.getSimpleName()));
5180 }
5181
5182 if ((flags & STATIC) != 0) {
5183 log.warning(LintCategory.SERIAL,
5184 TreeInfo.diagnosticPositionFor(method, tree),
5185 Warnings.SerialMethodStatic(method.getSimpleName()));
5186 }
5187 }
5188
5189 /**
5190 * Per section 1.12 "Serialization of Enum Constants" of
5191 * the serialization specification, due to the special
5192 * serialization handling of enums, any writeObject,
5193 * readObject, writeReplace, and readResolve methods are
5194 * ignored as are serialPersistentFields and
5195 * serialVersionUID fields.
5196 */
5197 @Override
5198 public Void visitTypeAsEnum(TypeElement e,
5199 JCClassDecl p) {
5200 boolean isExtern = isExternalizable((Type)e.asType());
5201 for(Element el : e.getEnclosedElements()) {
5202 runUnderLint(el, p, (enclosed, tree) -> {
5203 String name = enclosed.getSimpleName().toString();
5204 switch(enclosed.getKind()) {
5205 case FIELD -> {
5206 var field = (VarSymbol)enclosed;
5207 if (serialFieldNames.contains(name)) {
5208 log.warning(LintCategory.SERIAL,
5209 TreeInfo.diagnosticPositionFor(field, tree),
5210 Warnings.IneffectualSerialFieldEnum(name));
5211 }
5212 }
5213
5214 case METHOD -> {
5215 var method = (MethodSymbol)enclosed;
5216 if (serialMethodNames.contains(name)) {
5217 log.warning(LintCategory.SERIAL,
5218 TreeInfo.diagnosticPositionFor(method, tree),
5219 Warnings.IneffectualSerialMethodEnum(name));
5220 }
5221
5222 if (isExtern) {
5223 switch(name) {
5224 case "writeExternal" -> checkWriteExternalEnum(tree, e, method);
5225 case "readExternal" -> checkReadExternalEnum(tree, e, method);
5226 }
5227 }
5228 }
5229
5230 // Also perform checks on any class bodies of enum constants, see JLS 8.9.1.
5231 case ENUM_CONSTANT -> {
5232 var field = (VarSymbol)enclosed;
5233 JCVariableDecl decl = (JCVariableDecl) TreeInfo.declarationFor(field, p);
5234 if (decl.init instanceof JCNewClass nc && nc.def != null) {
5235 ClassSymbol enumConstantType = nc.def.sym;
5236 visitTypeAsEnum(enumConstantType, p);
5237 }
5238 }
5239
5240 }});
5241 }
5242 return null;
5243 }
5244
5245 private void checkWriteExternalEnum(JCClassDecl tree, Element e, MethodSymbol method) {
5246 //public void writeExternal(ObjectOutput) throws IOException
5247 checkExternMethodEnum(tree, e, method, syms.objectOutputType);
5248 }
5249
5250 private void checkReadExternalEnum(JCClassDecl tree, Element e, MethodSymbol method) {
5251 // public void readExternal(ObjectInput) throws IOException
5252 checkExternMethodEnum(tree, e, method, syms.objectInputType);
5253 }
5254
5255 private void checkExternMethodEnum(JCClassDecl tree, Element e, MethodSymbol method, Type argType) {
5256 if (isExternMethod(tree, e, method, argType)) {
5257 log.warning(LintCategory.SERIAL,
5258 TreeInfo.diagnosticPositionFor(method, tree),
5259 Warnings.IneffectualExternMethodEnum(method.getSimpleName().toString()));
5260 }
5261 }
5262
5263 private boolean isExternMethod(JCClassDecl tree, Element e, MethodSymbol method, Type argType) {
5264 long flags = method.flags();
5265 Type rtype = method.getReturnType();
5266
5267 // Not necessary to check throws clause in this context
5268 return (flags & PUBLIC) != 0 && (flags & STATIC) == 0 &&
5269 types.isSameType(syms.voidType, rtype) &&
5270 hasExactlyOneArgWithType(tree, e, method, argType);
5271 }
5272
5273 /**
5274 * Most serialization-related fields and methods on interfaces
5275 * are ineffectual or problematic.
5276 */
5277 @Override
5278 public Void visitTypeAsInterface(TypeElement e,
5279 JCClassDecl p) {
5280 for(Element el : e.getEnclosedElements()) {
5281 runUnderLint(el, p, (enclosed, tree) -> {
5282 String name = null;
5283 switch(enclosed.getKind()) {
5284 case FIELD -> {
5285 var field = (VarSymbol)enclosed;
5286 name = field.getSimpleName().toString();
5287 switch(name) {
5288 case "serialPersistentFields" -> {
5289 log.warning(LintCategory.SERIAL,
5290 TreeInfo.diagnosticPositionFor(field, tree),
5291 Warnings.IneffectualSerialFieldInterface);
5292 }
5293
5294 case "serialVersionUID" -> {
5295 checkSerialVersionUID(tree, e, field);
5296 }
5297 }
5298 }
5299
5300 case METHOD -> {
5301 var method = (MethodSymbol)enclosed;
5302 name = enclosed.getSimpleName().toString();
5303 if (serialMethodNames.contains(name)) {
5304 switch (name) {
5305 case
5306 "readObject",
5307 "readObjectNoData",
5308 "writeObject" -> checkPrivateMethod(tree, e, method);
5309
5310 case
5311 "writeReplace",
5312 "readResolve" -> checkDefaultIneffective(tree, e, method);
5313
5314 default -> throw new AssertionError();
5315 }
5316
5317 }
5318 }}
5319 });
5320 }
5321
5322 return null;
5323 }
5324
5325 private void checkPrivateMethod(JCClassDecl tree,
5326 Element e,
5327 MethodSymbol method) {
5328 if ((method.flags() & PRIVATE) == 0) {
5329 log.warning(LintCategory.SERIAL,
5330 TreeInfo.diagnosticPositionFor(method, tree),
5331 Warnings.NonPrivateMethodWeakerAccess);
5332 }
5333 }
5334
5335 private void checkDefaultIneffective(JCClassDecl tree,
5336 Element e,
5337 MethodSymbol method) {
5338 if ((method.flags() & DEFAULT) == DEFAULT) {
5339 log.warning(LintCategory.SERIAL,
5340 TreeInfo.diagnosticPositionFor(method, tree),
5341 Warnings.DefaultIneffective);
5342
5343 }
5344 }
5345
5346 @Override
5347 public Void visitTypeAsAnnotationType(TypeElement e,
5348 JCClassDecl p) {
5349 // Per the JLS, annotation types are not serializeable
5350 return null;
5351 }
5352
5353 /**
5354 * From the Java Object Serialization Specification, 1.13
5355 * Serialization of Records:
5356 *
5357 * "The process by which record objects are serialized or
5358 * externalized cannot be customized; any class-specific
5359 * writeObject, readObject, readObjectNoData, writeExternal,
5360 * and readExternal methods defined by record classes are
5361 * ignored during serialization and deserialization. However,
5362 * a substitute object to be serialized or a designate
5363 * replacement may be specified, by the writeReplace and
5364 * readResolve methods, respectively. Any
5365 * serialPersistentFields field declaration is
5366 * ignored. Documenting serializable fields and data for
5367 * record classes is unnecessary, since there is no variation
5368 * in the serial form, other than whether a substitute or
5369 * replacement object is used. The serialVersionUID of a
5370 * record class is 0L unless explicitly declared. The
5371 * requirement for matching serialVersionUID values is waived
5372 * for record classes."
5373 */
5374 @Override
5375 public Void visitTypeAsRecord(TypeElement e,
5376 JCClassDecl p) {
5377 boolean isExtern = isExternalizable((Type)e.asType());
5378 for(Element el : e.getEnclosedElements()) {
5379 runUnderLint(el, p, (enclosed, tree) -> {
5380 String name = enclosed.getSimpleName().toString();
5381 switch(enclosed.getKind()) {
5382 case FIELD -> {
5383 var field = (VarSymbol)enclosed;
5384 switch(name) {
5385 case "serialPersistentFields" -> {
5386 log.warning(LintCategory.SERIAL,
5387 TreeInfo.diagnosticPositionFor(field, tree),
5388 Warnings.IneffectualSerialFieldRecord);
5389 }
5390
5391 case "serialVersionUID" -> {
5392 // Could generate additional warning that
5393 // svuid value is not checked to match for
5394 // records.
5395 checkSerialVersionUID(tree, e, field);
5396 }}
5397 }
5398
5399 case METHOD -> {
5400 var method = (MethodSymbol)enclosed;
5401 switch(name) {
5402 case "writeReplace" -> checkWriteReplace(tree, e, method);
5403 case "readResolve" -> checkReadResolve(tree, e, method);
5404
5405 case "writeExternal" -> checkWriteExternalRecord(tree, e, method, isExtern);
5406 case "readExternal" -> checkReadExternalRecord(tree, e, method, isExtern);
5407
5408 default -> {
5409 if (serialMethodNames.contains(name)) {
5410 log.warning(LintCategory.SERIAL,
5411 TreeInfo.diagnosticPositionFor(method, tree),
5412 Warnings.IneffectualSerialMethodRecord(name));
5413 }
5414 }}
5415 }}});
5416 }
5417 return null;
5418 }
5419
5420 void checkConcreteInstanceMethod(JCClassDecl tree,
5421 Element enclosing,
5422 MethodSymbol method) {
5423 if ((method.flags() & (STATIC | ABSTRACT)) != 0) {
5424 log.warning(LintCategory.SERIAL,
5425 TreeInfo.diagnosticPositionFor(method, tree),
5426 Warnings.SerialConcreteInstanceMethod(method.getSimpleName()));
5427 }
5428 }
5429
5430 private void checkReturnType(JCClassDecl tree,
5431 Element enclosing,
5432 MethodSymbol method,
5433 Type expectedReturnType) {
5434 // Note: there may be complications checking writeReplace
5435 // and readResolve since they return Object and could, in
5436 // principle, have covariant overrides and any synthetic
5437 // bridge method would not be represented here for
5438 // checking.
5439 Type rtype = method.getReturnType();
5440 if (!types.isSameType(expectedReturnType, rtype)) {
5441 log.warning(LintCategory.SERIAL,
5442 TreeInfo.diagnosticPositionFor(method, tree),
5443 Warnings.SerialMethodUnexpectedReturnType(method.getSimpleName(),
5444 rtype, expectedReturnType));
5445 }
5446 }
5447
5448 private void checkOneArg(JCClassDecl tree,
5449 Element enclosing,
5450 MethodSymbol method,
5451 Type expectedType) {
5452 String name = method.getSimpleName().toString();
5453
5454 var parameters= method.getParameters();
5455
5456 if (parameters.size() != 1) {
5457 log.warning(LintCategory.SERIAL,
5458 TreeInfo.diagnosticPositionFor(method, tree),
5459 Warnings.SerialMethodOneArg(method.getSimpleName(), parameters.size()));
5460 return;
5461 }
5462
5463 Type parameterType = parameters.get(0).asType();
5464 if (!types.isSameType(parameterType, expectedType)) {
5465 log.warning(LintCategory.SERIAL,
5466 TreeInfo.diagnosticPositionFor(method, tree),
5467 Warnings.SerialMethodParameterType(method.getSimpleName(),
5468 expectedType,
5469 parameterType));
5470 }
5471 }
5472
5473 private boolean hasExactlyOneArgWithType(JCClassDecl tree,
5474 Element enclosing,
5475 MethodSymbol method,
5476 Type expectedType) {
5477 var parameters = method.getParameters();
5478 return (parameters.size() == 1) &&
5479 types.isSameType(parameters.get(0).asType(), expectedType);
5480 }
5481
5482
5483 private void checkNoArgs(JCClassDecl tree, Element enclosing, MethodSymbol method) {
5484 var parameters = method.getParameters();
5485 if (!parameters.isEmpty()) {
5486 log.warning(LintCategory.SERIAL,
5487 TreeInfo.diagnosticPositionFor(parameters.get(0), tree),
5488 Warnings.SerialMethodNoArgs(method.getSimpleName()));
5489 }
5490 }
5491
5492 private void checkExternalizable(JCClassDecl tree, Element enclosing, MethodSymbol method) {
5493 // If the enclosing class is externalizable, warn for the method
5494 if (isExternalizable((Type)enclosing.asType())) {
5495 log.warning(LintCategory.SERIAL,
5496 TreeInfo.diagnosticPositionFor(method, tree),
5497 Warnings.IneffectualSerialMethodExternalizable(method.getSimpleName()));
5498 }
5499 return;
5500 }
5501
5502 private void checkExceptions(JCClassDecl tree,
5503 Element enclosing,
5504 MethodSymbol method,
5505 Type... declaredExceptions) {
5506 for (Type thrownType: method.getThrownTypes()) {
5507 // For each exception in the throws clause of the
5508 // method, if not an Error and not a RuntimeException,
5509 // check if the exception is a subtype of a declared
5510 // exception from the throws clause of the
5511 // serialization method in question.
5512 if (types.isSubtype(thrownType, syms.runtimeExceptionType) ||
5513 types.isSubtype(thrownType, syms.errorType) ) {
5514 continue;
5515 } else {
5516 boolean declared = false;
5517 for (Type declaredException : declaredExceptions) {
5518 if (types.isSubtype(thrownType, declaredException)) {
5519 declared = true;
5520 continue;
5521 }
5522 }
5523 if (!declared) {
5524 log.warning(LintCategory.SERIAL,
5525 TreeInfo.diagnosticPositionFor(method, tree),
5526 Warnings.SerialMethodUnexpectedException(method.getSimpleName(),
5527 thrownType));
5528 }
5529 }
5530 }
5531 return;
5532 }
5533
5534 private <E extends Element> Void runUnderLint(E symbol, JCClassDecl p, BiConsumer<E, JCClassDecl> task) {
5535 Lint prevLint = lint;
5536 try {
5537 lint = lint.augment((Symbol) symbol);
5538
5539 if (lint.isEnabled(LintCategory.SERIAL)) {
5540 task.accept(symbol, p);
5541 }
5542
5543 return null;
5544 } finally {
5545 lint = prevLint;
5546 }
5547 }
5548
5549 }
5550
5551 }