1 /*
2 * Copyright (c) 1999, 2022, Oracle and/or its affiliates. All rights reserved.
3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
4 *
5 * This code is free software; you can redistribute it and/or modify it
6 * under the terms of the GNU General Public License version 2 only, as
7 * published by the Free Software Foundation. Oracle designates this
8 * particular file as subject to the "Classpath" exception as provided
9 * by Oracle in the LICENSE file that accompanied this code.
10 *
11 * This code is distributed in the hope that it will be useful, but WITHOUT
12 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
13 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
14 * version 2 for more details (a copy is included in the LICENSE file that
15 * accompanied this code).
16 *
17 * You should have received a copy of the GNU General Public License version
18 * 2 along with this work; if not, write to the Free Software Foundation,
19 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
20 *
21 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
22 * or visit www.oracle.com if you need additional information or have any
23 * questions.
24 */
25
26 package com.sun.tools.javac.comp;
27
28 import java.util.*;
29 import java.util.function.BiConsumer;
30 import java.util.function.Predicate;
31 import java.util.function.Supplier;
32
33 import javax.lang.model.element.ElementKind;
34 import javax.lang.model.element.NestingKind;
35 import javax.tools.JavaFileManager;
36
37 import com.sun.source.tree.CaseTree;
38 import com.sun.tools.javac.code.*;
39 import com.sun.tools.javac.code.Attribute.Compound;
40 import com.sun.tools.javac.code.Directive.ExportsDirective;
41 import com.sun.tools.javac.code.Directive.RequiresDirective;
42 import com.sun.tools.javac.code.Source.Feature;
43 import com.sun.tools.javac.comp.Annotate.AnnotationTypeMetadata;
44 import com.sun.tools.javac.jvm.*;
45 import com.sun.tools.javac.resources.CompilerProperties.Errors;
46 import com.sun.tools.javac.resources.CompilerProperties.Fragments;
47 import com.sun.tools.javac.resources.CompilerProperties.Warnings;
48 import com.sun.tools.javac.tree.*;
49 import com.sun.tools.javac.util.*;
50 import com.sun.tools.javac.util.JCDiagnostic.DiagnosticFlag;
51 import com.sun.tools.javac.util.JCDiagnostic.DiagnosticPosition;
52 import com.sun.tools.javac.util.JCDiagnostic.Error;
53 import com.sun.tools.javac.util.JCDiagnostic.Fragment;
54 import com.sun.tools.javac.util.JCDiagnostic.Warning;
55 import com.sun.tools.javac.util.List;
56
57 import com.sun.tools.javac.code.Lint;
58 import com.sun.tools.javac.code.Lint.LintCategory;
59 import com.sun.tools.javac.code.Scope.WriteableScope;
60 import com.sun.tools.javac.code.Type.*;
61 import com.sun.tools.javac.code.Symbol.*;
62 import com.sun.tools.javac.comp.DeferredAttr.DeferredAttrContext;
63 import com.sun.tools.javac.tree.JCTree.*;
64
65 import static com.sun.tools.javac.code.Flags.*;
66 import static com.sun.tools.javac.code.Flags.ANNOTATION;
67 import static com.sun.tools.javac.code.Flags.SYNCHRONIZED;
68 import static com.sun.tools.javac.code.Kinds.*;
69 import static com.sun.tools.javac.code.Kinds.Kind.*;
70 import static com.sun.tools.javac.code.Scope.LookupKind.NON_RECURSIVE;
71 import static com.sun.tools.javac.code.TypeTag.*;
72 import static com.sun.tools.javac.code.TypeTag.WILDCARD;
73
74 import static com.sun.tools.javac.tree.JCTree.Tag.*;
75 import javax.lang.model.element.Element;
76 import javax.lang.model.element.ExecutableElement;
77 import javax.lang.model.element.TypeElement;
78 import javax.lang.model.type.DeclaredType;
79 import javax.lang.model.type.TypeMirror;
80 import javax.lang.model.util.ElementFilter;
81 import javax.lang.model.util.ElementKindVisitor14;
82
83 /** Type checking helper class for the attribution phase.
84 *
85 * <p><b>This is NOT part of any supported API.
86 * If you write code that depends on this, you do so at your own risk.
87 * This code and its internal interfaces are subject to change or
88 * deletion without notice.</b>
89 */
90 public class Check {
91 protected static final Context.Key<Check> checkKey = new Context.Key<>();
92
93 private final Names names;
94 private final Log log;
95 private final Resolve rs;
96 private final Symtab syms;
97 private final Enter enter;
98 private final DeferredAttr deferredAttr;
99 private final Infer infer;
100 private final Types types;
101 private final TypeAnnotations typeAnnotations;
102 private final JCDiagnostic.Factory diags;
103 private final JavaFileManager fileManager;
104 private final Source source;
105 private final Target target;
106 private final Profile profile;
107 private final Preview preview;
108 private final boolean warnOnAnyAccessToMembers;
109
110 // The set of lint options currently in effect. It is initialized
111 // from the context, and then is set/reset as needed by Attr as it
112 // visits all the various parts of the trees during attribution.
113 private Lint lint;
114
115 // The method being analyzed in Attr - it is set/reset as needed by
116 // Attr as it visits new method declarations.
117 private MethodSymbol method;
118
119 public static Check instance(Context context) {
120 Check instance = context.get(checkKey);
121 if (instance == null)
122 instance = new Check(context);
123 return instance;
124 }
125
126 protected Check(Context context) {
127 context.put(checkKey, this);
128
129 names = Names.instance(context);
130 log = Log.instance(context);
131 rs = Resolve.instance(context);
132 syms = Symtab.instance(context);
133 enter = Enter.instance(context);
134 deferredAttr = DeferredAttr.instance(context);
135 infer = Infer.instance(context);
136 types = Types.instance(context);
137 typeAnnotations = TypeAnnotations.instance(context);
138 diags = JCDiagnostic.Factory.instance(context);
139 Options options = Options.instance(context);
140 lint = Lint.instance(context);
141 fileManager = context.get(JavaFileManager.class);
142
143 source = Source.instance(context);
144 target = Target.instance(context);
145 warnOnAnyAccessToMembers = options.isSet("warnOnAccessToMembers");
146
147 Target target = Target.instance(context);
148 syntheticNameChar = target.syntheticNameChar();
149
150 profile = Profile.instance(context);
151 preview = Preview.instance(context);
152
153 boolean verboseDeprecated = lint.isEnabled(LintCategory.DEPRECATION);
154 boolean verboseRemoval = lint.isEnabled(LintCategory.REMOVAL);
155 boolean verboseUnchecked = lint.isEnabled(LintCategory.UNCHECKED);
156 boolean enforceMandatoryWarnings = true;
157
158 deprecationHandler = new MandatoryWarningHandler(log, null, verboseDeprecated,
159 enforceMandatoryWarnings, "deprecated", LintCategory.DEPRECATION);
160 removalHandler = new MandatoryWarningHandler(log, null, verboseRemoval,
161 enforceMandatoryWarnings, "removal", LintCategory.REMOVAL);
162 uncheckedHandler = new MandatoryWarningHandler(log, null, verboseUnchecked,
163 enforceMandatoryWarnings, "unchecked", LintCategory.UNCHECKED);
164 sunApiHandler = new MandatoryWarningHandler(log, null, false,
165 enforceMandatoryWarnings, "sunapi", null);
166
167 deferredLintHandler = DeferredLintHandler.instance(context);
168
169 allowModules = Feature.MODULES.allowedInSource(source);
170 allowRecords = Feature.RECORDS.allowedInSource(source);
171 allowSealed = Feature.SEALED_CLASSES.allowedInSource(source);
172 allowPrimitiveClasses = Feature.PRIMITIVE_CLASSES.allowedInSource(source) && options.isSet("enablePrimitiveClasses");
173 }
174
175 /** Character for synthetic names
176 */
177 char syntheticNameChar;
178
179 /** A table mapping flat names of all compiled classes for each module in this run
180 * to their symbols; maintained from outside.
181 */
182 private Map<Pair<ModuleSymbol, Name>,ClassSymbol> compiled = new HashMap<>();
183
184 /** A handler for messages about deprecated usage.
185 */
186 private MandatoryWarningHandler deprecationHandler;
187
188 /** A handler for messages about deprecated-for-removal usage.
189 */
190 private MandatoryWarningHandler removalHandler;
191
192 /** A handler for messages about unchecked or unsafe usage.
193 */
194 private MandatoryWarningHandler uncheckedHandler;
195
196 /** A handler for messages about using proprietary API.
197 */
198 private MandatoryWarningHandler sunApiHandler;
199
200 /** A handler for deferred lint warnings.
201 */
202 private DeferredLintHandler deferredLintHandler;
203
204 /** Are modules allowed
205 */
206 private final boolean allowModules;
207
208 /** Are records allowed
209 */
210 private final boolean allowRecords;
211
212 /** Are sealed classes allowed
213 */
214 private final boolean allowSealed;
215
216 /** Are primitive classes allowed
217 */
218 private final boolean allowPrimitiveClasses;
219
220 /* *************************************************************************
221 * Errors and Warnings
222 **************************************************************************/
223
224 Lint setLint(Lint newLint) {
225 Lint prev = lint;
226 lint = newLint;
227 return prev;
228 }
229
230 MethodSymbol setMethod(MethodSymbol newMethod) {
231 MethodSymbol prev = method;
232 method = newMethod;
233 return prev;
234 }
235
236 /** Warn about deprecated symbol.
237 * @param pos Position to be used for error reporting.
238 * @param sym The deprecated symbol.
239 */
240 void warnDeprecated(DiagnosticPosition pos, Symbol sym) {
241 if (sym.isDeprecatedForRemoval()) {
242 if (!lint.isSuppressed(LintCategory.REMOVAL)) {
243 if (sym.kind == MDL) {
244 removalHandler.report(pos, Warnings.HasBeenDeprecatedForRemovalModule(sym));
245 } else {
246 removalHandler.report(pos, Warnings.HasBeenDeprecatedForRemoval(sym, sym.location()));
247 }
248 }
249 } else if (!lint.isSuppressed(LintCategory.DEPRECATION)) {
250 if (sym.kind == MDL) {
251 deprecationHandler.report(pos, Warnings.HasBeenDeprecatedModule(sym));
252 } else {
253 deprecationHandler.report(pos, Warnings.HasBeenDeprecated(sym, sym.location()));
254 }
255 }
256 }
257
258 /** Log a preview warning.
259 * @param pos Position to be used for error reporting.
260 * @param msg A Warning describing the problem.
261 */
262 public void warnPreviewAPI(DiagnosticPosition pos, Warning warnKey) {
263 if (!lint.isSuppressed(LintCategory.PREVIEW))
264 preview.reportPreviewWarning(pos, warnKey);
265 }
266
267 /** Log a preview warning.
268 * @param pos Position to be used for error reporting.
269 * @param msg A Warning describing the problem.
270 */
271 public void warnDeclaredUsingPreview(DiagnosticPosition pos, Symbol sym) {
272 if (!lint.isSuppressed(LintCategory.PREVIEW))
273 preview.reportPreviewWarning(pos, Warnings.DeclaredUsingPreview(kindName(sym), sym));
274 }
275
276 /** Warn about unchecked operation.
277 * @param pos Position to be used for error reporting.
278 * @param msg A string describing the problem.
279 */
280 public void warnUnchecked(DiagnosticPosition pos, Warning warnKey) {
281 if (!lint.isSuppressed(LintCategory.UNCHECKED))
282 uncheckedHandler.report(pos, warnKey);
283 }
284
285 /** Warn about unsafe vararg method decl.
286 * @param pos Position to be used for error reporting.
287 */
288 void warnUnsafeVararg(DiagnosticPosition pos, Warning warnKey) {
289 if (lint.isEnabled(LintCategory.VARARGS))
290 log.warning(LintCategory.VARARGS, pos, warnKey);
291 }
292
293 public void warnStatic(DiagnosticPosition pos, Warning warnKey) {
294 if (lint.isEnabled(LintCategory.STATIC))
295 log.warning(LintCategory.STATIC, pos, warnKey);
296 }
297
298 /** Warn about division by integer constant zero.
299 * @param pos Position to be used for error reporting.
300 */
301 void warnDivZero(DiagnosticPosition pos) {
302 if (lint.isEnabled(LintCategory.DIVZERO))
303 log.warning(LintCategory.DIVZERO, pos, Warnings.DivZero);
304 }
305
306 /**
307 * Report any deferred diagnostics.
308 */
309 public void reportDeferredDiagnostics() {
310 deprecationHandler.reportDeferredDiagnostic();
311 removalHandler.reportDeferredDiagnostic();
312 uncheckedHandler.reportDeferredDiagnostic();
313 sunApiHandler.reportDeferredDiagnostic();
314 }
315
316
317 /** Report a failure to complete a class.
318 * @param pos Position to be used for error reporting.
319 * @param ex The failure to report.
320 */
321 public Type completionError(DiagnosticPosition pos, CompletionFailure ex) {
322 log.error(JCDiagnostic.DiagnosticFlag.NON_DEFERRABLE, pos, Errors.CantAccess(ex.sym, ex.getDetailValue()));
323 return syms.errType;
324 }
325
326 /** Report an error that wrong type tag was found.
327 * @param pos Position to be used for error reporting.
328 * @param required An internationalized string describing the type tag
329 * required.
330 * @param found The type that was found.
331 */
332 Type typeTagError(DiagnosticPosition pos, JCDiagnostic required, Object found) {
333 // this error used to be raised by the parser,
334 // but has been delayed to this point:
335 if (found instanceof Type type && type.hasTag(VOID)) {
336 log.error(pos, Errors.IllegalStartOfType);
337 return syms.errType;
338 }
339 log.error(pos, Errors.TypeFoundReq(found, required));
340 return types.createErrorType(found instanceof Type type ? type : syms.errType);
341 }
342
343 /** Report an error that symbol cannot be referenced before super
344 * has been called.
345 * @param pos Position to be used for error reporting.
346 * @param sym The referenced symbol.
347 */
348 void earlyRefError(DiagnosticPosition pos, Symbol sym) {
349 log.error(pos, Errors.CantRefBeforeCtorCalled(sym));
350 }
351
352 /** Report duplicate declaration error.
353 */
354 void duplicateError(DiagnosticPosition pos, Symbol sym) {
355 if (!sym.type.isErroneous()) {
356 Symbol location = sym.location();
357 if (location.kind == MTH &&
358 ((MethodSymbol)location).isStaticOrInstanceInit()) {
359 log.error(pos,
360 Errors.AlreadyDefinedInClinit(kindName(sym),
361 sym,
362 kindName(sym.location()),
363 kindName(sym.location().enclClass()),
364 sym.location().enclClass()));
365 } else {
366 /* dont error if this is a duplicated parameter of a generated canonical constructor
367 * as we should have issued an error for the duplicated fields
368 */
369 if (location.kind != MTH ||
370 ((sym.owner.flags_field & GENERATEDCONSTR) == 0) ||
371 ((sym.owner.flags_field & RECORD) == 0)) {
372 log.error(pos,
373 Errors.AlreadyDefined(kindName(sym),
374 sym,
375 kindName(sym.location()),
376 sym.location()));
377 }
378 }
379 }
380 }
381
382 /** Report array/varargs duplicate declaration
383 */
384 void varargsDuplicateError(DiagnosticPosition pos, Symbol sym1, Symbol sym2) {
385 if (!sym1.type.isErroneous() && !sym2.type.isErroneous()) {
386 log.error(pos, Errors.ArrayAndVarargs(sym1, sym2, sym2.location()));
387 }
388 }
389
390 /* ************************************************************************
391 * duplicate declaration checking
392 *************************************************************************/
393
394 /** Check that variable does not hide variable with same name in
395 * immediately enclosing local scope.
396 * @param pos Position for error reporting.
397 * @param v The symbol.
398 * @param s The scope.
399 */
400 void checkTransparentVar(DiagnosticPosition pos, VarSymbol v, Scope s) {
401 for (Symbol sym : s.getSymbolsByName(v.name)) {
402 if (sym.owner != v.owner) break;
403 if (sym.kind == VAR &&
404 sym.owner.kind.matches(KindSelector.VAL_MTH) &&
405 v.name != names.error) {
406 duplicateError(pos, sym);
407 return;
408 }
409 }
410 }
411
412 /** Check that a class or interface does not hide a class or
413 * interface with same name in immediately enclosing local scope.
414 * @param pos Position for error reporting.
415 * @param c The symbol.
416 * @param s The scope.
417 */
418 void checkTransparentClass(DiagnosticPosition pos, ClassSymbol c, Scope s) {
419 for (Symbol sym : s.getSymbolsByName(c.name)) {
420 if (sym.owner != c.owner) break;
421 if (sym.kind == TYP && !sym.type.hasTag(TYPEVAR) &&
422 sym.owner.kind.matches(KindSelector.VAL_MTH) &&
423 c.name != names.error) {
424 duplicateError(pos, sym);
425 return;
426 }
427 }
428 }
429
430 /** Check that class does not have the same name as one of
431 * its enclosing classes, or as a class defined in its enclosing scope.
432 * return true if class is unique in its enclosing scope.
433 * @param pos Position for error reporting.
434 * @param name The class name.
435 * @param s The enclosing scope.
436 */
437 boolean checkUniqueClassName(DiagnosticPosition pos, Name name, Scope s) {
438 for (Symbol sym : s.getSymbolsByName(name, NON_RECURSIVE)) {
439 if (sym.kind == TYP && sym.name != names.error) {
440 duplicateError(pos, sym);
441 return false;
442 }
443 }
444 for (Symbol sym = s.owner; sym != null; sym = sym.owner) {
445 if (sym.kind == TYP && sym.name == name && sym.name != names.error) {
446 duplicateError(pos, sym);
447 return true;
448 }
449 }
450 return true;
451 }
452
453 /* *************************************************************************
454 * Class name generation
455 **************************************************************************/
456
457
458 private Map<Pair<Name, Name>, Integer> localClassNameIndexes = new HashMap<>();
459
460 /** Return name of local class.
461 * This is of the form {@code <enclClass> $ n <classname> }
462 * where
463 * enclClass is the flat name of the enclosing class,
464 * classname is the simple name of the local class
465 */
466 public Name localClassName(ClassSymbol c) {
467 Name enclFlatname = c.owner.enclClass().flatname;
468 String enclFlatnameStr = enclFlatname.toString();
469 Pair<Name, Name> key = new Pair<>(enclFlatname, c.name);
470 Integer index = localClassNameIndexes.get(key);
471 for (int i = (index == null) ? 1 : index; ; i++) {
472 Name flatname = names.fromString(enclFlatnameStr
473 + syntheticNameChar + i + c.name);
474 if (getCompiled(c.packge().modle, flatname) == null) {
475 localClassNameIndexes.put(key, i + 1);
476 return flatname;
477 }
478 }
479 }
480
481 public void clearLocalClassNameIndexes(ClassSymbol c) {
482 if (c.owner != null && c.owner.kind != NIL) {
483 localClassNameIndexes.remove(new Pair<>(
484 c.owner.enclClass().flatname, c.name));
485 }
486 }
487
488 public void newRound() {
489 compiled.clear();
490 localClassNameIndexes.clear();
491 }
492
493 public void clear() {
494 deprecationHandler.clear();
495 removalHandler.clear();
496 uncheckedHandler.clear();
497 sunApiHandler.clear();
498 }
499
500 public void putCompiled(ClassSymbol csym) {
501 compiled.put(Pair.of(csym.packge().modle, csym.flatname), csym);
502 }
503
504 public ClassSymbol getCompiled(ClassSymbol csym) {
505 return compiled.get(Pair.of(csym.packge().modle, csym.flatname));
506 }
507
508 public ClassSymbol getCompiled(ModuleSymbol msym, Name flatname) {
509 return compiled.get(Pair.of(msym, flatname));
510 }
511
512 public void removeCompiled(ClassSymbol csym) {
513 compiled.remove(Pair.of(csym.packge().modle, csym.flatname));
514 }
515
516 /* *************************************************************************
517 * Type Checking
518 **************************************************************************/
519
520 /**
521 * A check context is an object that can be used to perform compatibility
522 * checks - depending on the check context, meaning of 'compatibility' might
523 * vary significantly.
524 */
525 public interface CheckContext {
526 /**
527 * Is type 'found' compatible with type 'req' in given context
528 */
529 boolean compatible(Type found, Type req, Warner warn);
530 /**
531 * Report a check error
532 */
533 void report(DiagnosticPosition pos, JCDiagnostic details);
534 /**
535 * Obtain a warner for this check context
536 */
537 public Warner checkWarner(DiagnosticPosition pos, Type found, Type req);
538
539 public InferenceContext inferenceContext();
540
541 public DeferredAttr.DeferredAttrContext deferredAttrContext();
542 }
543
544 /**
545 * This class represent a check context that is nested within another check
546 * context - useful to check sub-expressions. The default behavior simply
547 * redirects all method calls to the enclosing check context leveraging
548 * the forwarding pattern.
549 */
550 static class NestedCheckContext implements CheckContext {
551 CheckContext enclosingContext;
552
553 NestedCheckContext(CheckContext enclosingContext) {
554 this.enclosingContext = enclosingContext;
555 }
556
557 public boolean compatible(Type found, Type req, Warner warn) {
558 return enclosingContext.compatible(found, req, warn);
559 }
560
561 public void report(DiagnosticPosition pos, JCDiagnostic details) {
562 enclosingContext.report(pos, details);
563 }
564
565 public Warner checkWarner(DiagnosticPosition pos, Type found, Type req) {
566 return enclosingContext.checkWarner(pos, found, req);
567 }
568
569 public InferenceContext inferenceContext() {
570 return enclosingContext.inferenceContext();
571 }
572
573 public DeferredAttrContext deferredAttrContext() {
574 return enclosingContext.deferredAttrContext();
575 }
576 }
577
578 /**
579 * Check context to be used when evaluating assignment/return statements
580 */
581 CheckContext basicHandler = new CheckContext() {
582 public void report(DiagnosticPosition pos, JCDiagnostic details) {
583 log.error(pos, Errors.ProbFoundReq(details));
584 }
585 public boolean compatible(Type found, Type req, Warner warn) {
586 return types.isAssignable(found, req, warn);
587 }
588
589 public Warner checkWarner(DiagnosticPosition pos, Type found, Type req) {
590 return convertWarner(pos, found, req);
591 }
592
593 public InferenceContext inferenceContext() {
594 return infer.emptyContext;
595 }
596
597 public DeferredAttrContext deferredAttrContext() {
598 return deferredAttr.emptyDeferredAttrContext;
599 }
600
601 @Override
602 public String toString() {
603 return "CheckContext: basicHandler";
604 }
605 };
606
607 /** Check that a given type is assignable to a given proto-type.
608 * If it is, return the type, otherwise return errType.
609 * @param pos Position to be used for error reporting.
610 * @param found The type that was found.
611 * @param req The type that was required.
612 */
613 public Type checkType(DiagnosticPosition pos, Type found, Type req) {
614 return checkType(pos, found, req, basicHandler);
615 }
616
617 Type checkType(final DiagnosticPosition pos, final Type found, final Type req, final CheckContext checkContext) {
618 final InferenceContext inferenceContext = checkContext.inferenceContext();
619 if (inferenceContext.free(req) || inferenceContext.free(found)) {
620 inferenceContext.addFreeTypeListener(List.of(req, found),
621 solvedContext -> checkType(pos, solvedContext.asInstType(found), solvedContext.asInstType(req), checkContext));
622 } else {
623 if (allowPrimitiveClasses && found.hasTag(CLASS)) {
624 if (inferenceContext != infer.emptyContext)
625 checkParameterizationByPrimitiveClass(pos, found);
626 }
627 }
628 if (req.hasTag(ERROR))
629 return req;
630 if (req.hasTag(NONE))
631 return found;
632 if (checkContext.compatible(found, req, checkContext.checkWarner(pos, found, req))) {
633 return found;
634 } else {
635 if (found.isNumeric() && req.isNumeric()) {
636 checkContext.report(pos, diags.fragment(Fragments.PossibleLossOfPrecision(found, req)));
637 return types.createErrorType(found);
638 }
639 checkContext.report(pos, diags.fragment(Fragments.InconvertibleTypes(found, req)));
640 return types.createErrorType(found);
641 }
642 }
643
644 /** Check that a given type can be cast to a given target type.
645 * Return the result of the cast.
646 * @param pos Position to be used for error reporting.
647 * @param found The type that is being cast.
648 * @param req The target type of the cast.
649 */
650 Type checkCastable(DiagnosticPosition pos, Type found, Type req) {
651 return checkCastable(pos, found, req, basicHandler);
652 }
653 Type checkCastable(DiagnosticPosition pos, Type found, Type req, CheckContext checkContext) {
654 if (types.isCastable(found, req, castWarner(pos, found, req))) {
655 return req;
656 } else {
657 checkContext.report(pos, diags.fragment(Fragments.InconvertibleTypes(found, req)));
658 return types.createErrorType(found);
659 }
660 }
661
662 /** Check for redundant casts (i.e. where source type is a subtype of target type)
663 * The problem should only be reported for non-292 cast
664 */
665 public void checkRedundantCast(Env<AttrContext> env, final JCTypeCast tree) {
666 if (!tree.type.isErroneous()
667 && types.isSameType(tree.expr.type, tree.clazz.type)
668 && !(ignoreAnnotatedCasts && TreeInfo.containsTypeAnnotation(tree.clazz))
669 && !is292targetTypeCast(tree)) {
670 deferredLintHandler.report(() -> {
671 if (lint.isEnabled(LintCategory.CAST))
672 log.warning(LintCategory.CAST,
673 tree.pos(), Warnings.RedundantCast(tree.clazz.type));
674 });
675 }
676 }
677 //where
678 private boolean is292targetTypeCast(JCTypeCast tree) {
679 boolean is292targetTypeCast = false;
680 JCExpression expr = TreeInfo.skipParens(tree.expr);
681 if (expr.hasTag(APPLY)) {
682 JCMethodInvocation apply = (JCMethodInvocation)expr;
683 Symbol sym = TreeInfo.symbol(apply.meth);
684 is292targetTypeCast = sym != null &&
685 sym.kind == MTH &&
686 (sym.flags() & HYPOTHETICAL) != 0;
687 }
688 return is292targetTypeCast;
689 }
690
691 private static final boolean ignoreAnnotatedCasts = true;
692
693 /** Check that a type is within some bounds.
694 *
695 * Used in TypeApply to verify that, e.g., X in {@code V<X>} is a valid
696 * type argument.
697 * @param a The type that should be bounded by bs.
698 * @param bound The bound.
699 */
700 private boolean checkExtends(Type a, Type bound) {
701 if (a.isUnbound()) {
702 return true;
703 } else if (!a.hasTag(WILDCARD)) {
704 a = types.cvarUpperBound(a);
705 return types.isSubtype(a, bound);
706 } else if (a.isExtendsBound()) {
707 return types.isCastable(bound, types.wildUpperBound(a), types.noWarnings);
708 } else if (a.isSuperBound()) {
709 return !types.notSoftSubtype(types.wildLowerBound(a), bound);
710 }
711 return true;
712 }
713
714 /** Check that type is different from 'void'.
715 * @param pos Position to be used for error reporting.
716 * @param t The type to be checked.
717 */
718 Type checkNonVoid(DiagnosticPosition pos, Type t) {
719 if (t.hasTag(VOID)) {
720 log.error(pos, Errors.VoidNotAllowedHere);
721 return types.createErrorType(t);
722 } else {
723 return t;
724 }
725 }
726
727 Type checkClassOrArrayType(DiagnosticPosition pos, Type t) {
728 if (!t.hasTag(CLASS) && !t.hasTag(ARRAY) && !t.hasTag(ERROR)) {
729 return typeTagError(pos,
730 diags.fragment(Fragments.TypeReqClassArray),
731 asTypeParam(t));
732 } else {
733 return t;
734 }
735 }
736
737 /** Check that type is a class or interface type.
738 * @param pos Position to be used for error reporting.
739 * @param t The type to be checked.
740 */
741 Type checkClassType(DiagnosticPosition pos, Type t) {
742 if (!t.hasTag(CLASS) && !t.hasTag(ERROR)) {
743 return typeTagError(pos,
744 diags.fragment(Fragments.TypeReqClass),
745 asTypeParam(t));
746 } else {
747 return t;
748 }
749 }
750 //where
751 private Object asTypeParam(Type t) {
752 return (t.hasTag(TYPEVAR))
753 ? diags.fragment(Fragments.TypeParameter(t))
754 : t;
755 }
756
757 void checkConstraintsOfValueClass(DiagnosticPosition pos, ClassSymbol c) {
758 for (Type st : types.closure(c.type)) {
759 if (st == null || st.tsym == null || st.tsym.kind == ERR)
760 continue;
761 if (st.tsym == syms.objectType.tsym || st.tsym == syms.recordType.tsym || st.isInterface())
762 continue;
763 if (!st.tsym.isAbstract()) {
764 if (c != st.tsym) {
765 log.error(pos, Errors.ConcreteSupertypeForValueClass(c, st));
766 }
767 continue;
768 }
769 // dealing with an abstract value or value super class below.
770 Fragment fragment = c.isAbstract() && c.isValueClass() && c == st.tsym ? Fragments.AbstractValueClass(c) : Fragments.SuperclassOfValueClass(c, st);
771 if ((st.tsym.flags() & HASINITBLOCK) != 0) {
772 log.error(pos, Errors.AbstractValueClassDeclaresInitBlock(fragment));
773 }
774 Type encl = st.getEnclosingType();
775 if (encl != null && encl.hasTag(CLASS)) {
776 log.error(pos, Errors.AbstractValueClassCannotBeInner(fragment));
777 }
778 for (Symbol s : st.tsym.members().getSymbols(NON_RECURSIVE)) {
779 switch (s.kind) {
780 case VAR:
781 if ((s.flags() & STATIC) == 0) {
782 log.error(pos, Errors.InstanceFieldNotAllowed(s, fragment));
783 }
784 break;
785 case MTH:
786 if ((s.flags() & (SYNCHRONIZED | STATIC)) == SYNCHRONIZED) {
787 log.error(pos, Errors.SuperClassMethodCannotBeSynchronized(s, c, st));
788 } else if (s.isInitOrVNew()) {
789 MethodSymbol m = (MethodSymbol)s;
790 if (m.getParameters().size() > 0) {
791 log.error(pos, Errors.AbstractValueClassConstructorCannotTakeArguments(m, fragment));
792 } else if (m.getTypeParameters().size() > 0) {
793 log.error(pos, Errors.AbstractValueClassConstructorCannotBeGeneric(m, fragment));
794 } else if (m.type.getThrownTypes().size() > 0) {
795 log.error(pos, Errors.AbstractValueClassConstructorCannotThrow(m, fragment));
796 } else if (protection(m.flags()) > protection(m.owner.flags())) {
797 log.error(pos, Errors.AbstractValueClassConstructorHasWeakerAccess(m, fragment));
798 } else if ((m.flags() & EMPTYNOARGCONSTR) == 0) {
799 log.error(pos, Errors.AbstractValueClassNoArgConstructorMustBeEmpty(m, fragment));
800 }
801 }
802 break;
803 }
804 }
805 }
806 }
807
808 /** Check that type is a valid qualifier for a constructor reference expression
809 */
810 Type checkConstructorRefType(JCExpression expr, Type t) {
811 t = checkClassOrArrayType(expr, t);
812 if (t.hasTag(CLASS)) {
813 if ((t.tsym.flags() & (ABSTRACT | INTERFACE)) != 0) {
814 log.error(expr, Errors.AbstractCantBeInstantiated(t.tsym));
815 t = types.createErrorType(t);
816 } else if ((t.tsym.flags() & ENUM) != 0) {
817 log.error(expr, Errors.EnumCantBeInstantiated);
818 t = types.createErrorType(t);
819 } else {
820 // Projection types may not be mentioned in constructor references
821 if (expr.hasTag(SELECT)) {
822 JCFieldAccess fieldAccess = (JCFieldAccess) expr;
823 if (allowPrimitiveClasses && fieldAccess.selected.type.isPrimitiveClass() &&
824 (fieldAccess.name == names.ref || fieldAccess.name == names.val)) {
825 log.error(expr, Errors.ProjectionCantBeInstantiated);
826 t = types.createErrorType(t);
827 }
828 }
829 t = checkClassType(expr, t, true);
830 }
831 } else if (t.hasTag(ARRAY)) {
832 if (!types.isReifiable(((ArrayType)t).elemtype)) {
833 log.error(expr, Errors.GenericArrayCreation);
834 t = types.createErrorType(t);
835 }
836 }
837 return t;
838 }
839
840 /** Check that type is a class or interface type.
841 * @param pos Position to be used for error reporting.
842 * @param t The type to be checked.
843 * @param noBounds True if type bounds are illegal here.
844 */
845 Type checkClassType(DiagnosticPosition pos, Type t, boolean noBounds) {
846 t = checkClassType(pos, t);
847 if (noBounds && t.isParameterized()) {
848 List<Type> args = t.getTypeArguments();
849 while (args.nonEmpty()) {
850 if (args.head.hasTag(WILDCARD))
851 return typeTagError(pos,
852 diags.fragment(Fragments.TypeReqExact),
853 args.head);
854 args = args.tail;
855 }
856 }
857 return t;
858 }
859
860 /** Check that type is a reference type, i.e. a class, interface or array type
861 * or a type variable.
862 * @param pos Position to be used for error reporting.
863 * @param t The type to be checked.
864 * @param primitiveClassOK If false, a primitive class does not qualify
865 */
866 Type checkRefType(DiagnosticPosition pos, Type t, boolean primitiveClassOK) {
867 if (t.isReference() && (!allowPrimitiveClasses || primitiveClassOK || !t.isPrimitiveClass()))
868 return t;
869 else
870 return typeTagError(pos,
871 diags.fragment(Fragments.TypeReqRef),
872 t);
873 }
874
875 /** Check that type is an identity type, i.e. not a primitive/value type
876 * nor its reference projection. When not discernible statically,
877 * give it the benefit of doubt and defer to runtime.
878 *
879 * @param pos Position to be used for error reporting.
880 * @param t The type to be checked.
881 */
882 void checkIdentityType(DiagnosticPosition pos, Type t) {
883 if (t.hasTag(TYPEVAR)) {
884 t = types.skipTypeVars(t, false);
885 }
886 if (t.isIntersection()) {
887 IntersectionClassType ict = (IntersectionClassType)t;
888 for (Type component : ict.getExplicitComponents()) {
889 checkIdentityType(pos, component);
890 }
891 return;
892 }
893 if (t.isPrimitive() || t.isValueClass() || t.isValueInterface() || t.isReferenceProjection())
894 typeTagError(pos, diags.fragment(Fragments.TypeReqIdentity), t);
895 }
896
897 /** Check that type is a reference type, i.e. a class, interface or array type
898 * or a type variable.
899 * @param pos Position to be used for error reporting.
900 * @param t The type to be checked.
901 */
902 Type checkRefType(DiagnosticPosition pos, Type t) {
903 return checkRefType(pos, t, true);
904 }
905
906 /** Check that each type is a reference type, i.e. a class, interface or array type
907 * or a type variable.
908 * @param trees Original trees, used for error reporting.
909 * @param types The types to be checked.
910 */
911 List<Type> checkRefTypes(List<JCExpression> trees, List<Type> types) {
912 List<JCExpression> tl = trees;
913 for (List<Type> l = types; l.nonEmpty(); l = l.tail) {
914 l.head = checkRefType(tl.head.pos(), l.head, false);
915 tl = tl.tail;
916 }
917 return types;
918 }
919
920 /** Check that type is a null or reference type.
921 * @param pos Position to be used for error reporting.
922 * @param t The type to be checked.
923 */
924 Type checkNullOrRefType(DiagnosticPosition pos, Type t) {
925 if (t.isReference() || t.hasTag(BOT))
926 return t;
927 else
928 return typeTagError(pos,
929 diags.fragment(Fragments.TypeReqRef),
930 t);
931 }
932
933 /** Check that flag set does not contain elements of two conflicting sets. s
934 * Return true if it doesn't.
935 * @param pos Position to be used for error reporting.
936 * @param flags The set of flags to be checked.
937 * @param set1 Conflicting flags set #1.
938 * @param set2 Conflicting flags set #2.
939 */
940 boolean checkDisjoint(DiagnosticPosition pos, long flags, long set1, long set2) {
941 if ((flags & set1) != 0 && (flags & set2) != 0) {
942 log.error(pos,
943 Errors.IllegalCombinationOfModifiers(asFlagSet(TreeInfo.firstFlag(flags & set1)),
944 asFlagSet(TreeInfo.firstFlag(flags & set2))));
945 return false;
946 } else
947 return true;
948 }
949
950 void checkParameterizationByPrimitiveClass(DiagnosticPosition pos, Type t) {
951 parameterizationByPrimitiveClassChecker.visit(t, pos);
952 }
953
954 /** parameterizationByPrimitiveClassChecker: A type visitor that descends down the given type looking for instances of primitive classes
955 * being used as type arguments and issues error against those usages.
956 */
957 private final Types.SimpleVisitor<Void, DiagnosticPosition> parameterizationByPrimitiveClassChecker =
958 new Types.SimpleVisitor<Void, DiagnosticPosition>() {
959
960 @Override
961 public Void visitType(Type t, DiagnosticPosition pos) {
962 return null;
963 }
964
965 @Override
966 public Void visitClassType(ClassType t, DiagnosticPosition pos) {
967 for (Type targ : t.allparams()) {
968 if (allowPrimitiveClasses && targ.isPrimitiveClass()) {
969 log.error(pos, Errors.GenericParameterizationWithPrimitiveClass(t));
970 }
971 visit(targ, pos);
972 }
973 return null;
974 }
975
976 @Override
977 public Void visitTypeVar(TypeVar t, DiagnosticPosition pos) {
978 return null;
979 }
980
981 @Override
982 public Void visitCapturedType(CapturedType t, DiagnosticPosition pos) {
983 return null;
984 }
985
986 @Override
987 public Void visitArrayType(ArrayType t, DiagnosticPosition pos) {
988 return visit(t.elemtype, pos);
989 }
990
991 @Override
992 public Void visitWildcardType(WildcardType t, DiagnosticPosition pos) {
993 return visit(t.type, pos);
994 }
995 };
996
997
998
999 /** Check that usage of diamond operator is correct (i.e. diamond should not
1000 * be used with non-generic classes or in anonymous class creation expressions)
1001 */
1002 Type checkDiamond(JCNewClass tree, Type t) {
1003 if (!TreeInfo.isDiamond(tree) ||
1004 t.isErroneous()) {
1005 return checkClassType(tree.clazz.pos(), t, true);
1006 } else {
1007 if (tree.def != null && !Feature.DIAMOND_WITH_ANONYMOUS_CLASS_CREATION.allowedInSource(source)) {
1008 log.error(DiagnosticFlag.SOURCE_LEVEL, tree.clazz.pos(),
1009 Errors.CantApplyDiamond1(t, Feature.DIAMOND_WITH_ANONYMOUS_CLASS_CREATION.fragment(source.name)));
1010 }
1011 if (t.tsym.type.getTypeArguments().isEmpty()) {
1012 log.error(tree.clazz.pos(),
1013 Errors.CantApplyDiamond1(t,
1014 Fragments.DiamondNonGeneric(t)));
1015 return types.createErrorType(t);
1016 } else if (tree.typeargs != null &&
1017 tree.typeargs.nonEmpty()) {
1018 log.error(tree.clazz.pos(),
1019 Errors.CantApplyDiamond1(t,
1020 Fragments.DiamondAndExplicitParams(t)));
1021 return types.createErrorType(t);
1022 } else {
1023 return t;
1024 }
1025 }
1026 }
1027
1028 /** Check that the type inferred using the diamond operator does not contain
1029 * non-denotable types such as captured types or intersection types.
1030 * @param t the type inferred using the diamond operator
1031 * @return the (possibly empty) list of non-denotable types.
1032 */
1033 List<Type> checkDiamondDenotable(ClassType t) {
1034 ListBuffer<Type> buf = new ListBuffer<>();
1035 for (Type arg : t.allparams()) {
1036 if (!checkDenotable(arg)) {
1037 buf.append(arg);
1038 }
1039 }
1040 return buf.toList();
1041 }
1042
1043 public boolean checkDenotable(Type t) {
1044 return denotableChecker.visit(t, null);
1045 }
1046 // where
1047
1048 /** diamondTypeChecker: A type visitor that descends down the given type looking for non-denotable
1049 * types. The visit methods return false as soon as a non-denotable type is encountered and true
1050 * otherwise.
1051 */
1052 private static final Types.SimpleVisitor<Boolean, Void> denotableChecker = new Types.SimpleVisitor<Boolean, Void>() {
1053 @Override
1054 public Boolean visitType(Type t, Void s) {
1055 return true;
1056 }
1057 @Override
1058 public Boolean visitClassType(ClassType t, Void s) {
1059 if (t.isUnion() || t.isIntersection()) {
1060 return false;
1061 }
1062 for (Type targ : t.allparams()) {
1063 if (!visit(targ, s)) {
1064 return false;
1065 }
1066 }
1067 return true;
1068 }
1069
1070 @Override
1071 public Boolean visitTypeVar(TypeVar t, Void s) {
1072 /* Any type variable mentioned in the inferred type must have been declared as a type parameter
1073 (i.e cannot have been produced by inference (18.4))
1074 */
1075 return (t.tsym.flags() & SYNTHETIC) == 0;
1076 }
1077
1078 @Override
1079 public Boolean visitCapturedType(CapturedType t, Void s) {
1080 /* Any type variable mentioned in the inferred type must have been declared as a type parameter
1081 (i.e cannot have been produced by capture conversion (5.1.10))
1082 */
1083 return false;
1084 }
1085
1086 @Override
1087 public Boolean visitArrayType(ArrayType t, Void s) {
1088 return visit(t.elemtype, s);
1089 }
1090
1091 @Override
1092 public Boolean visitWildcardType(WildcardType t, Void s) {
1093 return visit(t.type, s);
1094 }
1095 };
1096
1097 void checkVarargsMethodDecl(Env<AttrContext> env, JCMethodDecl tree) {
1098 MethodSymbol m = tree.sym;
1099 boolean hasTrustMeAnno = m.attribute(syms.trustMeType.tsym) != null;
1100 Type varargElemType = null;
1101 if (m.isVarArgs()) {
1102 varargElemType = types.elemtype(tree.params.last().type);
1103 }
1104 if (hasTrustMeAnno && !isTrustMeAllowedOnMethod(m)) {
1105 if (varargElemType != null) {
1106 JCDiagnostic msg = Feature.PRIVATE_SAFE_VARARGS.allowedInSource(source) ?
1107 diags.fragment(Fragments.VarargsTrustmeOnVirtualVarargs(m)) :
1108 diags.fragment(Fragments.VarargsTrustmeOnVirtualVarargsFinalOnly(m));
1109 log.error(tree,
1110 Errors.VarargsInvalidTrustmeAnno(syms.trustMeType.tsym,
1111 msg));
1112 } else {
1113 log.error(tree,
1114 Errors.VarargsInvalidTrustmeAnno(syms.trustMeType.tsym,
1115 Fragments.VarargsTrustmeOnNonVarargsMeth(m)));
1116 }
1117 } else if (hasTrustMeAnno && varargElemType != null &&
1118 types.isReifiable(varargElemType)) {
1119 warnUnsafeVararg(tree, Warnings.VarargsRedundantTrustmeAnno(
1120 syms.trustMeType.tsym,
1121 diags.fragment(Fragments.VarargsTrustmeOnReifiableVarargs(varargElemType))));
1122 }
1123 else if (!hasTrustMeAnno && varargElemType != null &&
1124 !types.isReifiable(varargElemType)) {
1125 warnUnchecked(tree.params.head.pos(), Warnings.UncheckedVarargsNonReifiableType(varargElemType));
1126 }
1127 }
1128 //where
1129 private boolean isTrustMeAllowedOnMethod(Symbol s) {
1130 return (s.flags() & VARARGS) != 0 &&
1131 (s.isInitOrVNew() ||
1132 (s.flags() & (STATIC | FINAL |
1133 (Feature.PRIVATE_SAFE_VARARGS.allowedInSource(source) ? PRIVATE : 0) )) != 0);
1134 }
1135
1136 Type checkLocalVarType(DiagnosticPosition pos, Type t, Name name) {
1137 //check that resulting type is not the null type
1138 if (t.hasTag(BOT)) {
1139 log.error(pos, Errors.CantInferLocalVarType(name, Fragments.LocalCantInferNull));
1140 return types.createErrorType(t);
1141 } else if (t.hasTag(VOID)) {
1142 log.error(pos, Errors.CantInferLocalVarType(name, Fragments.LocalCantInferVoid));
1143 return types.createErrorType(t);
1144 }
1145
1146 //upward project the initializer type
1147 Type varType = types.upward(t, types.captures(t)).baseType();
1148 if (allowPrimitiveClasses && varType.hasTag(CLASS)) {
1149 checkParameterizationByPrimitiveClass(pos, varType);
1150 }
1151 return varType;
1152 }
1153
1154 Type checkMethod(final Type mtype,
1155 final Symbol sym,
1156 final Env<AttrContext> env,
1157 final List<JCExpression> argtrees,
1158 final List<Type> argtypes,
1159 final boolean useVarargs,
1160 InferenceContext inferenceContext) {
1161 // System.out.println("call : " + env.tree);
1162 // System.out.println("method : " + owntype);
1163 // System.out.println("actuals: " + argtypes);
1164 if (inferenceContext.free(mtype)) {
1165 inferenceContext.addFreeTypeListener(List.of(mtype),
1166 solvedContext -> checkMethod(solvedContext.asInstType(mtype), sym, env, argtrees, argtypes, useVarargs, solvedContext));
1167 return mtype;
1168 }
1169 Type owntype = mtype;
1170 List<Type> formals = owntype.getParameterTypes();
1171 List<Type> nonInferred = sym.type.getParameterTypes();
1172 if (nonInferred.length() != formals.length()) nonInferred = formals;
1173 Type last = useVarargs ? formals.last() : null;
1174 // TODO - is enum so <init>
1175 if (sym.name == names.init && sym.owner == syms.enumSym) {
1176 formals = formals.tail.tail;
1177 nonInferred = nonInferred.tail.tail;
1178 }
1179 if ((sym.flags() & ANONCONSTR_BASED) != 0) {
1180 formals = formals.tail;
1181 nonInferred = nonInferred.tail;
1182 }
1183 List<JCExpression> args = argtrees;
1184 if (args != null) {
1185 //this is null when type-checking a method reference
1186 while (formals.head != last) {
1187 JCTree arg = args.head;
1188 Warner warn = convertWarner(arg.pos(), arg.type, nonInferred.head);
1189 assertConvertible(arg, arg.type, formals.head, warn);
1190 args = args.tail;
1191 formals = formals.tail;
1192 nonInferred = nonInferred.tail;
1193 }
1194 if (useVarargs) {
1195 Type varArg = types.elemtype(last);
1196 while (args.tail != null) {
1197 JCTree arg = args.head;
1198 Warner warn = convertWarner(arg.pos(), arg.type, varArg);
1199 assertConvertible(arg, arg.type, varArg, warn);
1200 args = args.tail;
1201 }
1202 } else if ((sym.flags() & (VARARGS | SIGNATURE_POLYMORPHIC)) == VARARGS) {
1203 // non-varargs call to varargs method
1204 Type varParam = owntype.getParameterTypes().last();
1205 Type lastArg = argtypes.last();
1206 if (types.isSubtypeUnchecked(lastArg, types.elemtype(varParam)) &&
1207 !types.isSameType(types.erasure(varParam), types.erasure(lastArg)))
1208 log.warning(argtrees.last().pos(),
1209 Warnings.InexactNonVarargsCall(types.elemtype(varParam),varParam));
1210 }
1211 }
1212 if (useVarargs) {
1213 Type argtype = owntype.getParameterTypes().last();
1214 if (!types.isReifiable(argtype) &&
1215 (sym.baseSymbol().attribute(syms.trustMeType.tsym) == null ||
1216 !isTrustMeAllowedOnMethod(sym))) {
1217 warnUnchecked(env.tree.pos(), Warnings.UncheckedGenericArrayCreation(argtype));
1218 }
1219 TreeInfo.setVarargsElement(env.tree, types.elemtype(argtype));
1220 }
1221 return owntype;
1222 }
1223 //where
1224 private void assertConvertible(JCTree tree, Type actual, Type formal, Warner warn) {
1225 if (types.isConvertible(actual, formal, warn))
1226 return;
1227
1228 if (formal.isCompound()
1229 && types.isSubtype(actual, types.supertype(formal))
1230 && types.isSubtypeUnchecked(actual, types.interfaces(formal), warn))
1231 return;
1232 }
1233
1234 /**
1235 * Check that type 't' is a valid instantiation of a generic class
1236 * (see JLS 4.5)
1237 *
1238 * @param t class type to be checked
1239 * @return true if 't' is well-formed
1240 */
1241 public boolean checkValidGenericType(Type t) {
1242 return firstIncompatibleTypeArg(t) == null;
1243 }
1244 //WHERE
1245 private Type firstIncompatibleTypeArg(Type type) {
1246 List<Type> formals = type.tsym.type.allparams();
1247 List<Type> actuals = type.allparams();
1248 List<Type> args = type.getTypeArguments();
1249 List<Type> forms = type.tsym.type.getTypeArguments();
1250 ListBuffer<Type> bounds_buf = new ListBuffer<>();
1251
1252 // For matching pairs of actual argument types `a' and
1253 // formal type parameters with declared bound `b' ...
1254 while (args.nonEmpty() && forms.nonEmpty()) {
1255 // exact type arguments needs to know their
1256 // bounds (for upper and lower bound
1257 // calculations). So we create new bounds where
1258 // type-parameters are replaced with actuals argument types.
1259 bounds_buf.append(types.subst(forms.head.getUpperBound(), formals, actuals));
1260 args = args.tail;
1261 forms = forms.tail;
1262 }
1263
1264 args = type.getTypeArguments();
1265 List<Type> tvars_cap = types.substBounds(formals,
1266 formals,
1267 types.capture(type).allparams());
1268 while (args.nonEmpty() && tvars_cap.nonEmpty()) {
1269 // Let the actual arguments know their bound
1270 args.head.withTypeVar((TypeVar)tvars_cap.head);
1271 args = args.tail;
1272 tvars_cap = tvars_cap.tail;
1273 }
1274
1275 args = type.getTypeArguments();
1276 List<Type> bounds = bounds_buf.toList();
1277
1278 while (args.nonEmpty() && bounds.nonEmpty()) {
1279 Type actual = args.head;
1280 if (!isTypeArgErroneous(actual) &&
1281 !bounds.head.isErroneous() &&
1282 !checkExtends(actual, bounds.head)) {
1283 return args.head;
1284 }
1285 args = args.tail;
1286 bounds = bounds.tail;
1287 }
1288
1289 args = type.getTypeArguments();
1290 bounds = bounds_buf.toList();
1291
1292 for (Type arg : types.capture(type).getTypeArguments()) {
1293 if (arg.hasTag(TYPEVAR) &&
1294 arg.getUpperBound().isErroneous() &&
1295 !bounds.head.isErroneous() &&
1296 !isTypeArgErroneous(args.head)) {
1297 return args.head;
1298 }
1299 bounds = bounds.tail;
1300 args = args.tail;
1301 }
1302
1303 return null;
1304 }
1305 //where
1306 boolean isTypeArgErroneous(Type t) {
1307 return isTypeArgErroneous.visit(t);
1308 }
1309
1310 Types.UnaryVisitor<Boolean> isTypeArgErroneous = new Types.UnaryVisitor<Boolean>() {
1311 public Boolean visitType(Type t, Void s) {
1312 return t.isErroneous();
1313 }
1314 @Override
1315 public Boolean visitTypeVar(TypeVar t, Void s) {
1316 return visit(t.getUpperBound());
1317 }
1318 @Override
1319 public Boolean visitCapturedType(CapturedType t, Void s) {
1320 return visit(t.getUpperBound()) ||
1321 visit(t.getLowerBound());
1322 }
1323 @Override
1324 public Boolean visitWildcardType(WildcardType t, Void s) {
1325 return visit(t.type);
1326 }
1327 };
1328
1329 /** Check that given modifiers are legal for given symbol and
1330 * return modifiers together with any implicit modifiers for that symbol.
1331 * Warning: we can't use flags() here since this method
1332 * is called during class enter, when flags() would cause a premature
1333 * completion.
1334 * @param pos Position to be used for error reporting.
1335 * @param flags The set of modifiers given in a definition.
1336 * @param sym The defined symbol.
1337 */
1338 long checkFlags(DiagnosticPosition pos, long flags, Symbol sym, JCTree tree) {
1339 long mask;
1340 long implicit = 0;
1341
1342 switch (sym.kind) {
1343 case VAR:
1344 if (TreeInfo.isReceiverParam(tree))
1345 mask = ReceiverParamFlags;
1346 else if (sym.owner.kind != TYP)
1347 mask = LocalVarFlags;
1348 else if ((sym.owner.flags_field & INTERFACE) != 0)
1349 mask = implicit = InterfaceVarFlags;
1350 else {
1351 mask = VarFlags;
1352 if (sym.owner.type.isValueClass() && (flags & STATIC) == 0) {
1353 implicit |= FINAL;
1354 }
1355 }
1356 break;
1357 case MTH:
1358 if (names.isInitOrVNew(sym.name)) {
1359 if ((sym.owner.flags_field & ENUM) != 0) {
1360 // enum constructors cannot be declared public or
1361 // protected and must be implicitly or explicitly
1362 // private
1363 implicit = PRIVATE;
1364 mask = PRIVATE;
1365 } else
1366 mask = ConstructorFlags;
1367 } else if ((sym.owner.flags_field & INTERFACE) != 0) {
1368 if ((sym.owner.flags_field & ANNOTATION) != 0) {
1369 mask = AnnotationTypeElementMask;
1370 implicit = PUBLIC | ABSTRACT;
1371 } else if ((flags & (DEFAULT | STATIC | PRIVATE)) != 0) {
1372 mask = InterfaceMethodMask;
1373 implicit = (flags & PRIVATE) != 0 ? 0 : PUBLIC;
1374 if ((flags & DEFAULT) != 0) {
1375 implicit |= ABSTRACT;
1376 }
1377 } else {
1378 mask = implicit = InterfaceMethodFlags;
1379 }
1380 } else if ((sym.owner.flags_field & RECORD) != 0) {
1381 mask = ((sym.owner.flags_field & VALUE_CLASS) != 0 && (flags & Flags.STATIC) == 0) ?
1382 RecordMethodFlags & ~SYNCHRONIZED : RecordMethodFlags;
1383 } else {
1384 // value objects do not have an associated monitor/lock
1385 mask = ((sym.owner.flags_field & VALUE_CLASS) != 0 && (flags & Flags.STATIC) == 0) ?
1386 MethodFlags & ~SYNCHRONIZED : MethodFlags;
1387 }
1388 if ((flags & STRICTFP) != 0) {
1389 warnOnExplicitStrictfp(pos);
1390 }
1391 // Imply STRICTFP if owner has STRICTFP set.
1392 if (((flags|implicit) & Flags.ABSTRACT) == 0 ||
1393 ((flags) & Flags.DEFAULT) != 0)
1394 implicit |= sym.owner.flags_field & STRICTFP;
1395 break;
1396 case TYP:
1397 if (sym.owner.kind.matches(KindSelector.VAL_MTH) ||
1398 (sym.isDirectlyOrIndirectlyLocal() && (flags & ANNOTATION) != 0)) {
1399 boolean implicitlyStatic = !sym.isAnonymous() &&
1400 ((flags & RECORD) != 0 || (flags & ENUM) != 0 || (flags & INTERFACE) != 0);
1401 boolean staticOrImplicitlyStatic = (flags & STATIC) != 0 || implicitlyStatic;
1402 // local statics are allowed only if records are allowed too
1403 mask = staticOrImplicitlyStatic && allowRecords && (flags & ANNOTATION) == 0 ? ExtendedStaticLocalClassFlags : ExtendedLocalClassFlags;
1404 implicit = implicitlyStatic ? STATIC : implicit;
1405 } else if (sym.owner.kind == TYP) {
1406 // statics in inner classes are allowed only if records are allowed too
1407 mask = ((flags & STATIC) != 0) && allowRecords && (flags & ANNOTATION) == 0 ? ExtendedMemberStaticClassFlags : ExtendedMemberClassFlags;
1408 if (sym.owner.owner.kind == PCK ||
1409 (sym.owner.flags_field & STATIC) != 0) {
1410 mask |= STATIC;
1411 } else if (!allowRecords && ((flags & ENUM) != 0 || (flags & RECORD) != 0)) {
1412 log.error(pos, Errors.StaticDeclarationNotAllowedInInnerClasses);
1413 }
1414 // Nested interfaces and enums are always STATIC (Spec ???)
1415 if ((flags & (INTERFACE | ENUM | RECORD)) != 0 ) implicit = STATIC;
1416 } else {
1417 mask = ExtendedClassFlags;
1418 }
1419 // Interfaces are always ABSTRACT
1420 if ((flags & INTERFACE) != 0) implicit |= ABSTRACT;
1421
1422 if ((flags & ENUM) != 0) {
1423 // enums can't be declared abstract, final, sealed or non-sealed or primitive/value
1424 mask &= ~(ABSTRACT | FINAL | SEALED | NON_SEALED | PRIMITIVE_CLASS | VALUE_CLASS);
1425 implicit |= implicitEnumFinalFlag(tree);
1426 }
1427 if ((flags & RECORD) != 0) {
1428 // records can't be declared abstract
1429 mask &= ~ABSTRACT;
1430 implicit |= FINAL;
1431 }
1432 if ((flags & STRICTFP) != 0) {
1433 warnOnExplicitStrictfp(pos);
1434 }
1435 // Imply STRICTFP if owner has STRICTFP set.
1436 implicit |= sym.owner.flags_field & STRICTFP;
1437
1438 // primitive classes are implicitly final value classes.
1439 if ((flags & PRIMITIVE_CLASS) != 0)
1440 implicit |= VALUE_CLASS | FINAL;
1441
1442 // concrete value classes are implicitly final
1443 if ((flags & (ABSTRACT | INTERFACE | VALUE_CLASS)) == VALUE_CLASS) {
1444 implicit |= FINAL;
1445 if ((flags & NON_SEALED) != 0) {
1446 // cant declare a final value class non-sealed
1447 log.error(pos,
1448 Errors.ModNotAllowedHere(asFlagSet(NON_SEALED)));
1449 }
1450 }
1451
1452 // TYPs can't be declared synchronized
1453 mask &= ~SYNCHRONIZED;
1454 break;
1455 default:
1456 throw new AssertionError();
1457 }
1458 long illegal = flags & ExtendedStandardFlags & ~mask;
1459 if (illegal != 0) {
1460 if ((illegal & INTERFACE) != 0) {
1461 log.error(pos, ((flags & ANNOTATION) != 0) ? Errors.AnnotationDeclNotAllowedHere : Errors.IntfNotAllowedHere);
1462 mask |= INTERFACE;
1463 }
1464 else {
1465 log.error(pos,
1466 Errors.ModNotAllowedHere(asFlagSet(illegal)));
1467 }
1468 }
1469 else if ((sym.kind == TYP ||
1470 // ISSUE: Disallowing abstract&private is no longer appropriate
1471 // in the presence of inner classes. Should it be deleted here?
1472 checkDisjoint(pos, flags,
1473 ABSTRACT,
1474 PRIVATE | STATIC | DEFAULT))
1475 &&
1476 checkDisjoint(pos, flags,
1477 STATIC | PRIVATE,
1478 DEFAULT)
1479 &&
1480 checkDisjoint(pos, flags,
1481 ABSTRACT | INTERFACE,
1482 FINAL | NATIVE | SYNCHRONIZED | PRIMITIVE_CLASS)
1483 &&
1484 checkDisjoint(pos, flags,
1485 IDENTITY_TYPE,
1486 PRIMITIVE_CLASS | VALUE_CLASS)
1487 &&
1488 checkDisjoint(pos, flags,
1489 PUBLIC,
1490 PRIVATE | PROTECTED)
1491 &&
1492 checkDisjoint(pos, flags,
1493 PRIVATE,
1494 PUBLIC | PROTECTED)
1495 &&
1496 checkDisjoint(pos, (flags | implicit), // complain against volatile & implcitly final entities too.
1497 FINAL,
1498 VOLATILE)
1499 &&
1500 (sym.kind == TYP ||
1501 checkDisjoint(pos, flags,
1502 ABSTRACT | NATIVE,
1503 STRICTFP))
1504 && checkDisjoint(pos, flags,
1505 FINAL,
1506 SEALED | NON_SEALED)
1507 && checkDisjoint(pos, flags,
1508 SEALED,
1509 FINAL | NON_SEALED)
1510 && checkDisjoint(pos, flags,
1511 SEALED,
1512 ANNOTATION)
1513 && checkDisjoint(pos, flags,
1514 IDENTITY_TYPE,
1515 ANNOTATION)
1516 && checkDisjoint(pos, flags,
1517 VALUE_CLASS,
1518 ANNOTATION) ) {
1519 // skip
1520 }
1521 return flags & (mask | ~ExtendedStandardFlags) | implicit;
1522 }
1523
1524 private void warnOnExplicitStrictfp(DiagnosticPosition pos) {
1525 DiagnosticPosition prevLintPos = deferredLintHandler.setPos(pos);
1526 try {
1527 deferredLintHandler.report(() -> {
1528 if (lint.isEnabled(LintCategory.STRICTFP)) {
1529 log.warning(LintCategory.STRICTFP,
1530 pos, Warnings.Strictfp); }
1531 });
1532 } finally {
1533 deferredLintHandler.setPos(prevLintPos);
1534 }
1535 }
1536
1537
1538 /** Determine if this enum should be implicitly final.
1539 *
1540 * If the enum has no specialized enum constants, it is final.
1541 *
1542 * If the enum does have specialized enum constants, it is
1543 * <i>not</i> final.
1544 */
1545 private long implicitEnumFinalFlag(JCTree tree) {
1546 if (!tree.hasTag(CLASSDEF)) return 0;
1547 class SpecialTreeVisitor extends JCTree.Visitor {
1548 boolean specialized;
1549 SpecialTreeVisitor() {
1550 this.specialized = false;
1551 }
1552
1553 @Override
1554 public void visitTree(JCTree tree) { /* no-op */ }
1555
1556 @Override
1557 public void visitVarDef(JCVariableDecl tree) {
1558 if ((tree.mods.flags & ENUM) != 0) {
1559 if (tree.init instanceof JCNewClass newClass && newClass.def != null) {
1560 specialized = true;
1561 }
1562 }
1563 }
1564 }
1565
1566 SpecialTreeVisitor sts = new SpecialTreeVisitor();
1567 JCClassDecl cdef = (JCClassDecl) tree;
1568 for (JCTree defs: cdef.defs) {
1569 defs.accept(sts);
1570 if (sts.specialized) return allowSealed ? SEALED : 0;
1571 }
1572 return FINAL;
1573 }
1574
1575 /* *************************************************************************
1576 * Type Validation
1577 **************************************************************************/
1578
1579 /** Validate a type expression. That is,
1580 * check that all type arguments of a parametric type are within
1581 * their bounds. This must be done in a second phase after type attribution
1582 * since a class might have a subclass as type parameter bound. E.g:
1583 *
1584 * <pre>{@code
1585 * class B<A extends C> { ... }
1586 * class C extends B<C> { ... }
1587 * }</pre>
1588 *
1589 * and we can't make sure that the bound is already attributed because
1590 * of possible cycles.
1591 *
1592 * Visitor method: Validate a type expression, if it is not null, catching
1593 * and reporting any completion failures.
1594 */
1595 void validate(JCTree tree, Env<AttrContext> env) {
1596 validate(tree, env, true);
1597 }
1598 void validate(JCTree tree, Env<AttrContext> env, boolean checkRaw) {
1599 new Validator(env).validateTree(tree, checkRaw, true);
1600 }
1601
1602 /** Visitor method: Validate a list of type expressions.
1603 */
1604 void validate(List<? extends JCTree> trees, Env<AttrContext> env) {
1605 for (List<? extends JCTree> l = trees; l.nonEmpty(); l = l.tail)
1606 validate(l.head, env);
1607 }
1608
1609 /** A visitor class for type validation.
1610 */
1611 class Validator extends JCTree.Visitor {
1612
1613 boolean checkRaw;
1614 boolean isOuter;
1615 Env<AttrContext> env;
1616
1617 Validator(Env<AttrContext> env) {
1618 this.env = env;
1619 }
1620
1621 @Override
1622 public void visitTypeArray(JCArrayTypeTree tree) {
1623 validateTree(tree.elemtype, checkRaw, isOuter);
1624 }
1625
1626 @Override
1627 public void visitTypeApply(JCTypeApply tree) {
1628 if (tree.type.hasTag(CLASS)) {
1629 List<JCExpression> args = tree.arguments;
1630 List<Type> forms = tree.type.tsym.type.getTypeArguments();
1631
1632 Type incompatibleArg = firstIncompatibleTypeArg(tree.type);
1633 if (incompatibleArg != null) {
1634 for (JCTree arg : tree.arguments) {
1635 if (arg.type == incompatibleArg) {
1636 log.error(arg, Errors.NotWithinBounds(incompatibleArg, forms.head));
1637 }
1638 forms = forms.tail;
1639 }
1640 }
1641
1642 forms = tree.type.tsym.type.getTypeArguments();
1643
1644 boolean is_java_lang_Class = tree.type.tsym.flatName() == names.java_lang_Class;
1645
1646 // For matching pairs of actual argument types `a' and
1647 // formal type parameters with declared bound `b' ...
1648 while (args.nonEmpty() && forms.nonEmpty()) {
1649 validateTree(args.head,
1650 !(isOuter && is_java_lang_Class),
1651 false);
1652 args = args.tail;
1653 forms = forms.tail;
1654 }
1655
1656 // Check that this type is either fully parameterized, or
1657 // not parameterized at all.
1658 if (tree.type.getEnclosingType().isRaw())
1659 log.error(tree.pos(), Errors.ImproperlyFormedTypeInnerRawParam);
1660 if (tree.clazz.hasTag(SELECT))
1661 visitSelectInternal((JCFieldAccess)tree.clazz);
1662 }
1663 }
1664
1665 @Override
1666 public void visitTypeParameter(JCTypeParameter tree) {
1667 validateTrees(tree.bounds, true, isOuter);
1668 checkClassBounds(tree.pos(), tree.type);
1669 }
1670
1671 @Override
1672 public void visitWildcard(JCWildcard tree) {
1673 if (tree.inner != null)
1674 validateTree(tree.inner, true, isOuter);
1675 }
1676
1677 @Override
1678 public void visitSelect(JCFieldAccess tree) {
1679 if (tree.type.hasTag(CLASS)) {
1680 visitSelectInternal(tree);
1681
1682 // Check that this type is either fully parameterized, or
1683 // not parameterized at all.
1684 if (tree.selected.type.isParameterized() && tree.type.tsym.type.getTypeArguments().nonEmpty())
1685 log.error(tree.pos(), Errors.ImproperlyFormedTypeParamMissing);
1686 }
1687 }
1688
1689 public void visitSelectInternal(JCFieldAccess tree) {
1690 if (tree.type.tsym.isStatic() &&
1691 tree.selected.type.isParameterized() &&
1692 (tree.name != names.ref || !tree.type.isReferenceProjection())) {
1693 // The enclosing type is not a class, so we are
1694 // looking at a static member type. However, the
1695 // qualifying expression is parameterized.
1696 // Tolerate the pseudo-select V.ref: V<T>.ref will be static if V<T> is and
1697 // should not be confused as selecting a static member of a parameterized type.
1698 log.error(tree.pos(), Errors.CantSelectStaticClassFromParamType);
1699 } else {
1700 // otherwise validate the rest of the expression
1701 tree.selected.accept(this);
1702 }
1703 }
1704
1705 @Override
1706 public void visitAnnotatedType(JCAnnotatedType tree) {
1707 tree.underlyingType.accept(this);
1708 }
1709
1710 @Override
1711 public void visitTypeIdent(JCPrimitiveTypeTree that) {
1712 if (that.type.hasTag(TypeTag.VOID)) {
1713 log.error(that.pos(), Errors.VoidNotAllowedHere);
1714 }
1715 super.visitTypeIdent(that);
1716 }
1717
1718 /** Default visitor method: do nothing.
1719 */
1720 @Override
1721 public void visitTree(JCTree tree) {
1722 }
1723
1724 public void validateTree(JCTree tree, boolean checkRaw, boolean isOuter) {
1725 if (tree != null) {
1726 boolean prevCheckRaw = this.checkRaw;
1727 this.checkRaw = checkRaw;
1728 this.isOuter = isOuter;
1729
1730 try {
1731 tree.accept(this);
1732 if (checkRaw)
1733 checkRaw(tree, env);
1734 } catch (CompletionFailure ex) {
1735 completionError(tree.pos(), ex);
1736 } finally {
1737 this.checkRaw = prevCheckRaw;
1738 }
1739 }
1740 }
1741
1742 public void validateTrees(List<? extends JCTree> trees, boolean checkRaw, boolean isOuter) {
1743 for (List<? extends JCTree> l = trees; l.nonEmpty(); l = l.tail)
1744 validateTree(l.head, checkRaw, isOuter);
1745 }
1746 }
1747
1748 void checkRaw(JCTree tree, Env<AttrContext> env) {
1749 if (lint.isEnabled(LintCategory.RAW) &&
1750 tree.type.hasTag(CLASS) &&
1751 !TreeInfo.isDiamond(tree) &&
1752 !withinAnonConstr(env) &&
1753 tree.type.isRaw()) {
1754 log.warning(LintCategory.RAW,
1755 tree.pos(), Warnings.RawClassUse(tree.type, tree.type.tsym.type));
1756 }
1757 }
1758 //where
1759 private boolean withinAnonConstr(Env<AttrContext> env) {
1760 return env.enclClass.name.isEmpty() &&
1761 env.enclMethod != null && names.isInitOrVNew(env.enclMethod.name);
1762 }
1763
1764 /* *************************************************************************
1765 * Exception checking
1766 **************************************************************************/
1767
1768 /* The following methods treat classes as sets that contain
1769 * the class itself and all their subclasses
1770 */
1771
1772 /** Is given type a subtype of some of the types in given list?
1773 */
1774 boolean subset(Type t, List<Type> ts) {
1775 for (List<Type> l = ts; l.nonEmpty(); l = l.tail)
1776 if (types.isSubtype(t, l.head)) return true;
1777 return false;
1778 }
1779
1780 /** Is given type a subtype or supertype of
1781 * some of the types in given list?
1782 */
1783 boolean intersects(Type t, List<Type> ts) {
1784 for (List<Type> l = ts; l.nonEmpty(); l = l.tail)
1785 if (types.isSubtype(t, l.head) || types.isSubtype(l.head, t)) return true;
1786 return false;
1787 }
1788
1789 /** Add type set to given type list, unless it is a subclass of some class
1790 * in the list.
1791 */
1792 List<Type> incl(Type t, List<Type> ts) {
1793 return subset(t, ts) ? ts : excl(t, ts).prepend(t);
1794 }
1795
1796 /** Remove type set from type set list.
1797 */
1798 List<Type> excl(Type t, List<Type> ts) {
1799 if (ts.isEmpty()) {
1800 return ts;
1801 } else {
1802 List<Type> ts1 = excl(t, ts.tail);
1803 if (types.isSubtype(ts.head, t)) return ts1;
1804 else if (ts1 == ts.tail) return ts;
1805 else return ts1.prepend(ts.head);
1806 }
1807 }
1808
1809 /** Form the union of two type set lists.
1810 */
1811 List<Type> union(List<Type> ts1, List<Type> ts2) {
1812 List<Type> ts = ts1;
1813 for (List<Type> l = ts2; l.nonEmpty(); l = l.tail)
1814 ts = incl(l.head, ts);
1815 return ts;
1816 }
1817
1818 /** Form the difference of two type lists.
1819 */
1820 List<Type> diff(List<Type> ts1, List<Type> ts2) {
1821 List<Type> ts = ts1;
1822 for (List<Type> l = ts2; l.nonEmpty(); l = l.tail)
1823 ts = excl(l.head, ts);
1824 return ts;
1825 }
1826
1827 /** Form the intersection of two type lists.
1828 */
1829 public List<Type> intersect(List<Type> ts1, List<Type> ts2) {
1830 List<Type> ts = List.nil();
1831 for (List<Type> l = ts1; l.nonEmpty(); l = l.tail)
1832 if (subset(l.head, ts2)) ts = incl(l.head, ts);
1833 for (List<Type> l = ts2; l.nonEmpty(); l = l.tail)
1834 if (subset(l.head, ts1)) ts = incl(l.head, ts);
1835 return ts;
1836 }
1837
1838 /** Is exc an exception symbol that need not be declared?
1839 */
1840 boolean isUnchecked(ClassSymbol exc) {
1841 return
1842 exc.kind == ERR ||
1843 exc.isSubClass(syms.errorType.tsym, types) ||
1844 exc.isSubClass(syms.runtimeExceptionType.tsym, types);
1845 }
1846
1847 /** Is exc an exception type that need not be declared?
1848 */
1849 boolean isUnchecked(Type exc) {
1850 return
1851 (exc.hasTag(TYPEVAR)) ? isUnchecked(types.supertype(exc)) :
1852 (exc.hasTag(CLASS)) ? isUnchecked((ClassSymbol)exc.tsym) :
1853 exc.hasTag(BOT);
1854 }
1855
1856 boolean isChecked(Type exc) {
1857 return !isUnchecked(exc);
1858 }
1859
1860 /** Same, but handling completion failures.
1861 */
1862 boolean isUnchecked(DiagnosticPosition pos, Type exc) {
1863 try {
1864 return isUnchecked(exc);
1865 } catch (CompletionFailure ex) {
1866 completionError(pos, ex);
1867 return true;
1868 }
1869 }
1870
1871 /** Is exc handled by given exception list?
1872 */
1873 boolean isHandled(Type exc, List<Type> handled) {
1874 return isUnchecked(exc) || subset(exc, handled);
1875 }
1876
1877 /** Return all exceptions in thrown list that are not in handled list.
1878 * @param thrown The list of thrown exceptions.
1879 * @param handled The list of handled exceptions.
1880 */
1881 List<Type> unhandled(List<Type> thrown, List<Type> handled) {
1882 List<Type> unhandled = List.nil();
1883 for (List<Type> l = thrown; l.nonEmpty(); l = l.tail)
1884 if (!isHandled(l.head, handled)) unhandled = unhandled.prepend(l.head);
1885 return unhandled;
1886 }
1887
1888 /* *************************************************************************
1889 * Overriding/Implementation checking
1890 **************************************************************************/
1891
1892 /** The level of access protection given by a flag set,
1893 * where PRIVATE is highest and PUBLIC is lowest.
1894 */
1895 static int protection(long flags) {
1896 switch ((short)(flags & AccessFlags)) {
1897 case PRIVATE: return 3;
1898 case PROTECTED: return 1;
1899 default:
1900 case PUBLIC: return 0;
1901 case 0: return 2;
1902 }
1903 }
1904
1905 /** A customized "cannot override" error message.
1906 * @param m The overriding method.
1907 * @param other The overridden method.
1908 * @return An internationalized string.
1909 */
1910 Fragment cannotOverride(MethodSymbol m, MethodSymbol other) {
1911 Symbol mloc = m.location();
1912 Symbol oloc = other.location();
1913
1914 if ((other.owner.flags() & INTERFACE) == 0)
1915 return Fragments.CantOverride(m, mloc, other, oloc);
1916 else if ((m.owner.flags() & INTERFACE) == 0)
1917 return Fragments.CantImplement(m, mloc, other, oloc);
1918 else
1919 return Fragments.ClashesWith(m, mloc, other, oloc);
1920 }
1921
1922 /** A customized "override" warning message.
1923 * @param m The overriding method.
1924 * @param other The overridden method.
1925 * @return An internationalized string.
1926 */
1927 Fragment uncheckedOverrides(MethodSymbol m, MethodSymbol other) {
1928 Symbol mloc = m.location();
1929 Symbol oloc = other.location();
1930
1931 if ((other.owner.flags() & INTERFACE) == 0)
1932 return Fragments.UncheckedOverride(m, mloc, other, oloc);
1933 else if ((m.owner.flags() & INTERFACE) == 0)
1934 return Fragments.UncheckedImplement(m, mloc, other, oloc);
1935 else
1936 return Fragments.UncheckedClashWith(m, mloc, other, oloc);
1937 }
1938
1939 /** A customized "override" warning message.
1940 * @param m The overriding method.
1941 * @param other The overridden method.
1942 * @return An internationalized string.
1943 */
1944 Fragment varargsOverrides(MethodSymbol m, MethodSymbol other) {
1945 Symbol mloc = m.location();
1946 Symbol oloc = other.location();
1947
1948 if ((other.owner.flags() & INTERFACE) == 0)
1949 return Fragments.VarargsOverride(m, mloc, other, oloc);
1950 else if ((m.owner.flags() & INTERFACE) == 0)
1951 return Fragments.VarargsImplement(m, mloc, other, oloc);
1952 else
1953 return Fragments.VarargsClashWith(m, mloc, other, oloc);
1954 }
1955
1956 /** Check that this method conforms with overridden method 'other'.
1957 * where `origin' is the class where checking started.
1958 * Complications:
1959 * (1) Do not check overriding of synthetic methods
1960 * (reason: they might be final).
1961 * todo: check whether this is still necessary.
1962 * (2) Admit the case where an interface proxy throws fewer exceptions
1963 * than the method it implements. Augment the proxy methods with the
1964 * undeclared exceptions in this case.
1965 * (3) When generics are enabled, admit the case where an interface proxy
1966 * has a result type
1967 * extended by the result type of the method it implements.
1968 * Change the proxies result type to the smaller type in this case.
1969 *
1970 * @param tree The tree from which positions
1971 * are extracted for errors.
1972 * @param m The overriding method.
1973 * @param other The overridden method.
1974 * @param origin The class of which the overriding method
1975 * is a member.
1976 */
1977 void checkOverride(JCTree tree,
1978 MethodSymbol m,
1979 MethodSymbol other,
1980 ClassSymbol origin) {
1981 // Don't check overriding of synthetic methods or by bridge methods.
1982 if ((m.flags() & (SYNTHETIC|BRIDGE)) != 0 || (other.flags() & SYNTHETIC) != 0) {
1983 return;
1984 }
1985
1986 // Error if static method overrides instance method (JLS 8.4.8.2).
1987 if ((m.flags() & STATIC) != 0 &&
1988 (other.flags() & STATIC) == 0) {
1989 log.error(TreeInfo.diagnosticPositionFor(m, tree),
1990 Errors.OverrideStatic(cannotOverride(m, other)));
1991 m.flags_field |= BAD_OVERRIDE;
1992 return;
1993 }
1994
1995 // Error if instance method overrides static or final
1996 // method (JLS 8.4.8.1).
1997 if ((other.flags() & FINAL) != 0 ||
1998 (m.flags() & STATIC) == 0 &&
1999 (other.flags() & STATIC) != 0) {
2000 log.error(TreeInfo.diagnosticPositionFor(m, tree),
2001 Errors.OverrideMeth(cannotOverride(m, other),
2002 asFlagSet(other.flags() & (FINAL | STATIC))));
2003 m.flags_field |= BAD_OVERRIDE;
2004 return;
2005 }
2006
2007 if ((m.owner.flags() & ANNOTATION) != 0) {
2008 // handled in validateAnnotationMethod
2009 return;
2010 }
2011
2012 // Error if overriding method has weaker access (JLS 8.4.8.3).
2013 if (protection(m.flags()) > protection(other.flags())) {
2014 log.error(TreeInfo.diagnosticPositionFor(m, tree),
2015 (other.flags() & AccessFlags) == 0 ?
2016 Errors.OverrideWeakerAccess(cannotOverride(m, other),
2017 "package") :
2018 Errors.OverrideWeakerAccess(cannotOverride(m, other),
2019 asFlagSet(other.flags() & AccessFlags)));
2020 m.flags_field |= BAD_OVERRIDE;
2021 return;
2022 }
2023
2024 if (shouldCheckPreview(m, other, origin)) {
2025 checkPreview(tree.pos(), m, other);
2026 }
2027
2028 Type mt = types.memberType(origin.type, m);
2029 Type ot = types.memberType(origin.type, other);
2030 // Error if overriding result type is different
2031 // (or, in the case of generics mode, not a subtype) of
2032 // overridden result type. We have to rename any type parameters
2033 // before comparing types.
2034 List<Type> mtvars = mt.getTypeArguments();
2035 List<Type> otvars = ot.getTypeArguments();
2036 Type mtres = mt.getReturnType();
2037 Type otres = types.subst(ot.getReturnType(), otvars, mtvars);
2038
2039 overrideWarner.clear();
2040 boolean resultTypesOK =
2041 types.returnTypeSubstitutable(mt, ot, otres, overrideWarner);
2042 if (!resultTypesOK) {
2043 if ((m.flags() & STATIC) != 0 && (other.flags() & STATIC) != 0) {
2044 log.error(TreeInfo.diagnosticPositionFor(m, tree),
2045 Errors.OverrideIncompatibleRet(Fragments.CantHide(m, m.location(), other,
2046 other.location()), mtres, otres));
2047 m.flags_field |= BAD_OVERRIDE;
2048 } else {
2049 log.error(TreeInfo.diagnosticPositionFor(m, tree),
2050 Errors.OverrideIncompatibleRet(cannotOverride(m, other), mtres, otres));
2051 m.flags_field |= BAD_OVERRIDE;
2052 }
2053 return;
2054 } else if (overrideWarner.hasNonSilentLint(LintCategory.UNCHECKED)) {
2055 warnUnchecked(TreeInfo.diagnosticPositionFor(m, tree),
2056 Warnings.OverrideUncheckedRet(uncheckedOverrides(m, other), mtres, otres));
2057 }
2058
2059 // Error if overriding method throws an exception not reported
2060 // by overridden method.
2061 List<Type> otthrown = types.subst(ot.getThrownTypes(), otvars, mtvars);
2062 List<Type> unhandledErased = unhandled(mt.getThrownTypes(), types.erasure(otthrown));
2063 List<Type> unhandledUnerased = unhandled(mt.getThrownTypes(), otthrown);
2064 if (unhandledErased.nonEmpty()) {
2065 log.error(TreeInfo.diagnosticPositionFor(m, tree),
2066 Errors.OverrideMethDoesntThrow(cannotOverride(m, other), unhandledUnerased.head));
2067 m.flags_field |= BAD_OVERRIDE;
2068 return;
2069 }
2070 else if (unhandledUnerased.nonEmpty()) {
2071 warnUnchecked(TreeInfo.diagnosticPositionFor(m, tree),
2072 Warnings.OverrideUncheckedThrown(cannotOverride(m, other), unhandledUnerased.head));
2073 return;
2074 }
2075
2076 // Optional warning if varargs don't agree
2077 if ((((m.flags() ^ other.flags()) & Flags.VARARGS) != 0)
2078 && lint.isEnabled(LintCategory.OVERRIDES)) {
2079 log.warning(TreeInfo.diagnosticPositionFor(m, tree),
2080 ((m.flags() & Flags.VARARGS) != 0)
2081 ? Warnings.OverrideVarargsMissing(varargsOverrides(m, other))
2082 : Warnings.OverrideVarargsExtra(varargsOverrides(m, other)));
2083 }
2084
2085 // Warn if instance method overrides bridge method (compiler spec ??)
2086 if ((other.flags() & BRIDGE) != 0) {
2087 log.warning(TreeInfo.diagnosticPositionFor(m, tree),
2088 Warnings.OverrideBridge(uncheckedOverrides(m, other)));
2089 }
2090
2091 // Warn if a deprecated method overridden by a non-deprecated one.
2092 if (!isDeprecatedOverrideIgnorable(other, origin)) {
2093 Lint prevLint = setLint(lint.augment(m));
2094 try {
2095 checkDeprecated(() -> TreeInfo.diagnosticPositionFor(m, tree), m, other);
2096 } finally {
2097 setLint(prevLint);
2098 }
2099 }
2100 }
2101 // where
2102 private boolean shouldCheckPreview(MethodSymbol m, MethodSymbol other, ClassSymbol origin) {
2103 if (m.owner != origin ||
2104 //performance - only do the expensive checks when the overridden method is a Preview API:
2105 (other.flags() & PREVIEW_API) == 0) {
2106 return false;
2107 }
2108
2109 for (Symbol s : types.membersClosure(origin.type, false).getSymbolsByName(m.name)) {
2110 if (m != s && m.overrides(s, origin, types, false)) {
2111 //only produce preview warnings or errors if "m" immediatelly overrides "other"
2112 //without intermediate overriding methods:
2113 return s == other;
2114 }
2115 }
2116
2117 return false;
2118 }
2119 private boolean isDeprecatedOverrideIgnorable(MethodSymbol m, ClassSymbol origin) {
2120 // If the method, m, is defined in an interface, then ignore the issue if the method
2121 // is only inherited via a supertype and also implemented in the supertype,
2122 // because in that case, we will rediscover the issue when examining the method
2123 // in the supertype.
2124 // If the method, m, is not defined in an interface, then the only time we need to
2125 // address the issue is when the method is the supertype implementation: any other
2126 // case, we will have dealt with when examining the supertype classes
2127 ClassSymbol mc = m.enclClass();
2128 Type st = types.supertype(origin.type);
2129 if (!st.hasTag(CLASS))
2130 return true;
2131 MethodSymbol stimpl = m.implementation((ClassSymbol)st.tsym, types, false);
2132
2133 if (mc != null && ((mc.flags() & INTERFACE) != 0)) {
2134 List<Type> intfs = types.interfaces(origin.type);
2135 return (intfs.contains(mc.type) ? false : (stimpl != null));
2136 }
2137 else
2138 return (stimpl != m);
2139 }
2140
2141
2142 // used to check if there were any unchecked conversions
2143 Warner overrideWarner = new Warner();
2144
2145 /** Check that a class does not inherit two concrete methods
2146 * with the same signature.
2147 * @param pos Position to be used for error reporting.
2148 * @param site The class type to be checked.
2149 */
2150 public void checkCompatibleConcretes(DiagnosticPosition pos, Type site) {
2151 Type sup = types.supertype(site);
2152 if (!sup.hasTag(CLASS)) return;
2153
2154 for (Type t1 = sup;
2155 t1.hasTag(CLASS) && t1.tsym.type.isParameterized();
2156 t1 = types.supertype(t1)) {
2157 for (Symbol s1 : t1.tsym.members().getSymbols(NON_RECURSIVE)) {
2158 if (s1.kind != MTH ||
2159 (s1.flags() & (STATIC|SYNTHETIC|BRIDGE)) != 0 ||
2160 !s1.isInheritedIn(site.tsym, types) ||
2161 ((MethodSymbol)s1).implementation(site.tsym,
2162 types,
2163 true) != s1)
2164 continue;
2165 Type st1 = types.memberType(t1, s1);
2166 int s1ArgsLength = st1.getParameterTypes().length();
2167 if (st1 == s1.type) continue;
2168
2169 for (Type t2 = sup;
2170 t2.hasTag(CLASS);
2171 t2 = types.supertype(t2)) {
2172 for (Symbol s2 : t2.tsym.members().getSymbolsByName(s1.name)) {
2173 if (s2 == s1 ||
2174 s2.kind != MTH ||
2175 (s2.flags() & (STATIC|SYNTHETIC|BRIDGE)) != 0 ||
2176 s2.type.getParameterTypes().length() != s1ArgsLength ||
2177 !s2.isInheritedIn(site.tsym, types) ||
2178 ((MethodSymbol)s2).implementation(site.tsym,
2179 types,
2180 true) != s2)
2181 continue;
2182 Type st2 = types.memberType(t2, s2);
2183 if (types.overrideEquivalent(st1, st2))
2184 log.error(pos,
2185 Errors.ConcreteInheritanceConflict(s1, t1, s2, t2, sup));
2186 }
2187 }
2188 }
2189 }
2190 }
2191
2192 /** Check that classes (or interfaces) do not each define an abstract
2193 * method with same name and arguments but incompatible return types.
2194 * @param pos Position to be used for error reporting.
2195 * @param t1 The first argument type.
2196 * @param t2 The second argument type.
2197 */
2198 public boolean checkCompatibleAbstracts(DiagnosticPosition pos,
2199 Type t1,
2200 Type t2,
2201 Type site) {
2202 if ((site.tsym.flags() & COMPOUND) != 0) {
2203 // special case for intersections: need to eliminate wildcards in supertypes
2204 t1 = types.capture(t1);
2205 t2 = types.capture(t2);
2206 }
2207 return firstIncompatibility(pos, t1, t2, site) == null;
2208 }
2209
2210 /** Return the first method which is defined with same args
2211 * but different return types in two given interfaces, or null if none
2212 * exists.
2213 * @param t1 The first type.
2214 * @param t2 The second type.
2215 * @param site The most derived type.
2216 * @return symbol from t2 that conflicts with one in t1.
2217 */
2218 private Symbol firstIncompatibility(DiagnosticPosition pos, Type t1, Type t2, Type site) {
2219 Map<TypeSymbol,Type> interfaces1 = new HashMap<>();
2220 closure(t1, interfaces1);
2221 Map<TypeSymbol,Type> interfaces2;
2222 if (t1 == t2)
2223 interfaces2 = interfaces1;
2224 else
2225 closure(t2, interfaces1, interfaces2 = new HashMap<>());
2226
2227 for (Type t3 : interfaces1.values()) {
2228 for (Type t4 : interfaces2.values()) {
2229 Symbol s = firstDirectIncompatibility(pos, t3, t4, site);
2230 if (s != null) return s;
2231 }
2232 }
2233 return null;
2234 }
2235
2236 /** Compute all the supertypes of t, indexed by type symbol. */
2237 private void closure(Type t, Map<TypeSymbol,Type> typeMap) {
2238 if (!t.hasTag(CLASS)) return;
2239 if (typeMap.put(t.tsym, t) == null) {
2240 closure(types.supertype(t), typeMap);
2241 for (Type i : types.interfaces(t))
2242 closure(i, typeMap);
2243 }
2244 }
2245
2246 /** Compute all the supertypes of t, indexed by type symbol (except those in typesSkip). */
2247 private void closure(Type t, Map<TypeSymbol,Type> typesSkip, Map<TypeSymbol,Type> typeMap) {
2248 if (!t.hasTag(CLASS)) return;
2249 if (typesSkip.get(t.tsym) != null) return;
2250 if (typeMap.put(t.tsym, t) == null) {
2251 closure(types.supertype(t), typesSkip, typeMap);
2252 for (Type i : types.interfaces(t))
2253 closure(i, typesSkip, typeMap);
2254 }
2255 }
2256
2257 /** Return the first method in t2 that conflicts with a method from t1. */
2258 private Symbol firstDirectIncompatibility(DiagnosticPosition pos, Type t1, Type t2, Type site) {
2259 for (Symbol s1 : t1.tsym.members().getSymbols(NON_RECURSIVE)) {
2260 Type st1 = null;
2261 if (s1.kind != MTH || !s1.isInheritedIn(site.tsym, types) ||
2262 (s1.flags() & SYNTHETIC) != 0) continue;
2263 Symbol impl = ((MethodSymbol)s1).implementation(site.tsym, types, false);
2264 if (impl != null && (impl.flags() & ABSTRACT) == 0) continue;
2265 for (Symbol s2 : t2.tsym.members().getSymbolsByName(s1.name)) {
2266 if (s1 == s2) continue;
2267 if (s2.kind != MTH || !s2.isInheritedIn(site.tsym, types) ||
2268 (s2.flags() & SYNTHETIC) != 0) continue;
2269 if (st1 == null) st1 = types.memberType(t1, s1);
2270 Type st2 = types.memberType(t2, s2);
2271 if (types.overrideEquivalent(st1, st2)) {
2272 List<Type> tvars1 = st1.getTypeArguments();
2273 List<Type> tvars2 = st2.getTypeArguments();
2274 Type rt1 = st1.getReturnType();
2275 Type rt2 = types.subst(st2.getReturnType(), tvars2, tvars1);
2276 boolean compat =
2277 types.isSameType(rt1, rt2) ||
2278 !rt1.isPrimitiveOrVoid() &&
2279 !rt2.isPrimitiveOrVoid() &&
2280 (types.covariantReturnType(rt1, rt2, types.noWarnings) ||
2281 types.covariantReturnType(rt2, rt1, types.noWarnings)) ||
2282 checkCommonOverriderIn(s1,s2,site);
2283 if (!compat) {
2284 if (types.isSameType(t1, t2)) {
2285 log.error(pos, Errors.IncompatibleDiffRetSameType(t1,
2286 s2.name, types.memberType(t2, s2).getParameterTypes()));
2287 } else {
2288 log.error(pos, Errors.TypesIncompatible(t1, t2,
2289 Fragments.IncompatibleDiffRet(s2.name, types.memberType(t2, s2).getParameterTypes())));
2290 }
2291 return s2;
2292 }
2293 } else if (checkNameClash((ClassSymbol)site.tsym, s1, s2) &&
2294 !checkCommonOverriderIn(s1, s2, site)) {
2295 log.error(pos, Errors.NameClashSameErasureNoOverride(
2296 s1.name, types.memberType(site, s1).asMethodType().getParameterTypes(), s1.location(),
2297 s2.name, types.memberType(site, s2).asMethodType().getParameterTypes(), s2.location()));
2298 return s2;
2299 }
2300 }
2301 }
2302 return null;
2303 }
2304 //WHERE
2305 boolean checkCommonOverriderIn(Symbol s1, Symbol s2, Type site) {
2306 Map<TypeSymbol,Type> supertypes = new HashMap<>();
2307 Type st1 = types.memberType(site, s1);
2308 Type st2 = types.memberType(site, s2);
2309 closure(site, supertypes);
2310 for (Type t : supertypes.values()) {
2311 for (Symbol s3 : t.tsym.members().getSymbolsByName(s1.name)) {
2312 if (s3 == s1 || s3 == s2 || s3.kind != MTH || (s3.flags() & (BRIDGE|SYNTHETIC)) != 0) continue;
2313 Type st3 = types.memberType(site,s3);
2314 if (types.overrideEquivalent(st3, st1) &&
2315 types.overrideEquivalent(st3, st2) &&
2316 types.returnTypeSubstitutable(st3, st1) &&
2317 types.returnTypeSubstitutable(st3, st2)) {
2318 return true;
2319 }
2320 }
2321 }
2322 return false;
2323 }
2324
2325 /** Check that a given method conforms with any method it overrides.
2326 * @param tree The tree from which positions are extracted
2327 * for errors.
2328 * @param m The overriding method.
2329 */
2330 void checkOverride(Env<AttrContext> env, JCMethodDecl tree, MethodSymbol m) {
2331 ClassSymbol origin = (ClassSymbol)m.owner;
2332 if ((origin.flags() & ENUM) != 0 && names.finalize.equals(m.name)) {
2333 if (m.overrides(syms.enumFinalFinalize, origin, types, false)) {
2334 log.error(tree.pos(), Errors.EnumNoFinalize);
2335 return;
2336 }
2337 }
2338 if (allowRecords && origin.isRecord()) {
2339 // let's find out if this is a user defined accessor in which case the @Override annotation is acceptable
2340 Optional<? extends RecordComponent> recordComponent = origin.getRecordComponents().stream()
2341 .filter(rc -> rc.accessor == tree.sym && (rc.accessor.flags_field & GENERATED_MEMBER) == 0).findFirst();
2342 if (recordComponent.isPresent()) {
2343 return;
2344 }
2345 }
2346
2347 for (Type t = origin.type; t.hasTag(CLASS);
2348 t = types.supertype(t)) {
2349 if (t != origin.type) {
2350 checkOverride(tree, t, origin, m);
2351 }
2352 for (Type t2 : types.interfaces(t)) {
2353 checkOverride(tree, t2, origin, m);
2354 }
2355 }
2356
2357 final boolean explicitOverride = m.attribute(syms.overrideType.tsym) != null;
2358 // Check if this method must override a super method due to being annotated with @Override
2359 // or by virtue of being a member of a diamond inferred anonymous class. Latter case is to
2360 // be treated "as if as they were annotated" with @Override.
2361 boolean mustOverride = explicitOverride ||
2362 (env.info.isAnonymousDiamond && !m.isInitOrVNew() && !m.isPrivate());
2363 if (mustOverride && !isOverrider(m)) {
2364 DiagnosticPosition pos = tree.pos();
2365 for (JCAnnotation a : tree.getModifiers().annotations) {
2366 if (a.annotationType.type.tsym == syms.overrideType.tsym) {
2367 pos = a.pos();
2368 break;
2369 }
2370 }
2371 log.error(pos,
2372 explicitOverride ? (m.isStatic() ? Errors.StaticMethodsCannotBeAnnotatedWithOverride : Errors.MethodDoesNotOverrideSuperclass) :
2373 Errors.AnonymousDiamondMethodDoesNotOverrideSuperclass(Fragments.DiamondAnonymousMethodsImplicitlyOverride));
2374 }
2375 }
2376
2377 void checkOverride(JCTree tree, Type site, ClassSymbol origin, MethodSymbol m) {
2378 TypeSymbol c = site.tsym;
2379 for (Symbol sym : c.members().getSymbolsByName(m.name)) {
2380 if (m.overrides(sym, origin, types, false)) {
2381 if ((sym.flags() & ABSTRACT) == 0) {
2382 checkOverride(tree, m, (MethodSymbol)sym, origin);
2383 }
2384 }
2385 }
2386 }
2387
2388 private Predicate<Symbol> equalsHasCodeFilter = s -> MethodSymbol.implementation_filter.test(s) &&
2389 (s.flags() & BAD_OVERRIDE) == 0;
2390
2391 public void checkClassOverrideEqualsAndHashIfNeeded(DiagnosticPosition pos,
2392 ClassSymbol someClass) {
2393 /* At present, annotations cannot possibly have a method that is override
2394 * equivalent with Object.equals(Object) but in any case the condition is
2395 * fine for completeness.
2396 */
2397 if (someClass == (ClassSymbol)syms.objectType.tsym ||
2398 someClass.isInterface() || someClass.isEnum() ||
2399 (someClass.flags() & ANNOTATION) != 0 ||
2400 (someClass.flags() & ABSTRACT) != 0) return;
2401 //anonymous inner classes implementing interfaces need especial treatment
2402 if (someClass.isAnonymous()) {
2403 List<Type> interfaces = types.interfaces(someClass.type);
2404 if (interfaces != null && !interfaces.isEmpty() &&
2405 interfaces.head.tsym == syms.comparatorType.tsym) return;
2406 }
2407 checkClassOverrideEqualsAndHash(pos, someClass);
2408 }
2409
2410 private void checkClassOverrideEqualsAndHash(DiagnosticPosition pos,
2411 ClassSymbol someClass) {
2412 if (lint.isEnabled(LintCategory.OVERRIDES)) {
2413 MethodSymbol equalsAtObject = (MethodSymbol)syms.objectType
2414 .tsym.members().findFirst(names.equals);
2415 MethodSymbol hashCodeAtObject = (MethodSymbol)syms.objectType
2416 .tsym.members().findFirst(names.hashCode);
2417 MethodSymbol equalsImpl = types.implementation(equalsAtObject,
2418 someClass, false, equalsHasCodeFilter);
2419 boolean overridesEquals = equalsImpl != null &&
2420 equalsImpl.owner == someClass;
2421 boolean overridesHashCode = types.implementation(hashCodeAtObject,
2422 someClass, false, equalsHasCodeFilter) != hashCodeAtObject;
2423
2424 if (overridesEquals && !overridesHashCode) {
2425 log.warning(LintCategory.OVERRIDES, pos,
2426 Warnings.OverrideEqualsButNotHashcode(someClass));
2427 }
2428 }
2429 }
2430
2431 public void checkModuleName (JCModuleDecl tree) {
2432 Name moduleName = tree.sym.name;
2433 Assert.checkNonNull(moduleName);
2434 if (lint.isEnabled(LintCategory.MODULE)) {
2435 JCExpression qualId = tree.qualId;
2436 while (qualId != null) {
2437 Name componentName;
2438 DiagnosticPosition pos;
2439 switch (qualId.getTag()) {
2440 case SELECT:
2441 JCFieldAccess selectNode = ((JCFieldAccess) qualId);
2442 componentName = selectNode.name;
2443 pos = selectNode.pos();
2444 qualId = selectNode.selected;
2445 break;
2446 case IDENT:
2447 componentName = ((JCIdent) qualId).name;
2448 pos = qualId.pos();
2449 qualId = null;
2450 break;
2451 default:
2452 throw new AssertionError("Unexpected qualified identifier: " + qualId.toString());
2453 }
2454 if (componentName != null) {
2455 String moduleNameComponentString = componentName.toString();
2456 int nameLength = moduleNameComponentString.length();
2457 if (nameLength > 0 && Character.isDigit(moduleNameComponentString.charAt(nameLength - 1))) {
2458 log.warning(Lint.LintCategory.MODULE, pos, Warnings.PoorChoiceForModuleName(componentName));
2459 }
2460 }
2461 }
2462 }
2463 }
2464
2465 private boolean checkNameClash(ClassSymbol origin, Symbol s1, Symbol s2) {
2466 ClashFilter cf = new ClashFilter(origin.type);
2467 return (cf.test(s1) &&
2468 cf.test(s2) &&
2469 types.hasSameArgs(s1.erasure(types), s2.erasure(types)));
2470 }
2471
2472
2473 /** Check that all abstract members of given class have definitions.
2474 * @param pos Position to be used for error reporting.
2475 * @param c The class.
2476 */
2477 void checkAllDefined(DiagnosticPosition pos, ClassSymbol c) {
2478 MethodSymbol undef = types.firstUnimplementedAbstract(c);
2479 if (undef != null) {
2480 MethodSymbol undef1 =
2481 new MethodSymbol(undef.flags(), undef.name,
2482 types.memberType(c.type, undef), undef.owner);
2483 log.error(pos,
2484 Errors.DoesNotOverrideAbstract(c, undef1, undef1.location()));
2485 }
2486 }
2487
2488 // A primitive class cannot contain a field of its own type either or indirectly.
2489 void checkNonCyclicMembership(JCClassDecl tree) {
2490 if (allowPrimitiveClasses) {
2491 Assert.check((tree.sym.flags_field & LOCKED) == 0);
2492 try {
2493 tree.sym.flags_field |= LOCKED;
2494 for (List<? extends JCTree> l = tree.defs; l.nonEmpty(); l = l.tail) {
2495 if (l.head.hasTag(VARDEF)) {
2496 JCVariableDecl field = (JCVariableDecl) l.head;
2497 if (cyclePossible(field.sym)) {
2498 checkNonCyclicMembership((ClassSymbol) field.type.tsym, field.pos());
2499 }
2500 }
2501 }
2502 } finally {
2503 tree.sym.flags_field &= ~LOCKED;
2504 }
2505 }
2506 }
2507 // where
2508 private void checkNonCyclicMembership(ClassSymbol c, DiagnosticPosition pos) {
2509 if ((c.flags_field & LOCKED) != 0) {
2510 log.error(pos, Errors.CyclicPrimitiveClassMembership(c));
2511 return;
2512 }
2513 try {
2514 c.flags_field |= LOCKED;
2515 for (Symbol fld : c.members().getSymbols(s -> s.kind == VAR && cyclePossible((VarSymbol) s), NON_RECURSIVE)) {
2516 checkNonCyclicMembership((ClassSymbol) fld.type.tsym, pos);
2517 }
2518 } finally {
2519 c.flags_field &= ~LOCKED;
2520 }
2521 }
2522 // where
2523 private boolean cyclePossible(VarSymbol symbol) {
2524 return (symbol.flags() & STATIC) == 0 && allowPrimitiveClasses && symbol.type.isPrimitiveClass();
2525 }
2526
2527 void checkNonCyclicDecl(JCClassDecl tree) {
2528 CycleChecker cc = new CycleChecker();
2529 cc.scan(tree);
2530 if (!cc.errorFound && !cc.partialCheck) {
2531 tree.sym.flags_field |= ACYCLIC;
2532 }
2533 }
2534
2535 class CycleChecker extends TreeScanner {
2536
2537 Set<Symbol> seenClasses = new HashSet<>();
2538 boolean errorFound = false;
2539 boolean partialCheck = false;
2540
2541 private void checkSymbol(DiagnosticPosition pos, Symbol sym) {
2542 if (sym != null && sym.kind == TYP) {
2543 Env<AttrContext> classEnv = enter.getEnv((TypeSymbol)sym);
2544 if (classEnv != null) {
2545 DiagnosticSource prevSource = log.currentSource();
2546 try {
2547 log.useSource(classEnv.toplevel.sourcefile);
2548 scan(classEnv.tree);
2549 }
2550 finally {
2551 log.useSource(prevSource.getFile());
2552 }
2553 } else if (sym.kind == TYP) {
2554 checkClass(pos, sym, List.nil());
2555 }
2556 } else if (sym == null || sym.kind != PCK) {
2557 //not completed yet
2558 partialCheck = true;
2559 }
2560 }
2561
2562 @Override
2563 public void visitSelect(JCFieldAccess tree) {
2564 super.visitSelect(tree);
2565 checkSymbol(tree.pos(), tree.sym);
2566 }
2567
2568 @Override
2569 public void visitIdent(JCIdent tree) {
2570 checkSymbol(tree.pos(), tree.sym);
2571 }
2572
2573 @Override
2574 public void visitTypeApply(JCTypeApply tree) {
2575 scan(tree.clazz);
2576 }
2577
2578 @Override
2579 public void visitTypeArray(JCArrayTypeTree tree) {
2580 scan(tree.elemtype);
2581 }
2582
2583 @Override
2584 public void visitClassDef(JCClassDecl tree) {
2585 List<JCTree> supertypes = List.nil();
2586 if (tree.getExtendsClause() != null) {
2587 supertypes = supertypes.prepend(tree.getExtendsClause());
2588 }
2589 if (tree.getImplementsClause() != null) {
2590 for (JCTree intf : tree.getImplementsClause()) {
2591 supertypes = supertypes.prepend(intf);
2592 }
2593 }
2594 checkClass(tree.pos(), tree.sym, supertypes);
2595 }
2596
2597 void checkClass(DiagnosticPosition pos, Symbol c, List<JCTree> supertypes) {
2598 if ((c.flags_field & ACYCLIC) != 0)
2599 return;
2600 if (seenClasses.contains(c)) {
2601 errorFound = true;
2602 noteCyclic(pos, (ClassSymbol)c);
2603 } else if (!c.type.isErroneous()) {
2604 try {
2605 seenClasses.add(c);
2606 if (c.type.hasTag(CLASS)) {
2607 if (supertypes.nonEmpty()) {
2608 scan(supertypes);
2609 }
2610 else {
2611 ClassType ct = (ClassType)c.type;
2612 if (ct.supertype_field == null ||
2613 ct.interfaces_field == null) {
2614 //not completed yet
2615 partialCheck = true;
2616 return;
2617 }
2618 checkSymbol(pos, ct.supertype_field.tsym);
2619 for (Type intf : ct.interfaces_field) {
2620 checkSymbol(pos, intf.tsym);
2621 }
2622 }
2623 if (c.owner.kind == TYP) {
2624 checkSymbol(pos, c.owner);
2625 }
2626 }
2627 } finally {
2628 seenClasses.remove(c);
2629 }
2630 }
2631 }
2632 }
2633
2634 /** Check for cyclic references. Issue an error if the
2635 * symbol of the type referred to has a LOCKED flag set.
2636 *
2637 * @param pos Position to be used for error reporting.
2638 * @param t The type referred to.
2639 */
2640 void checkNonCyclic(DiagnosticPosition pos, Type t) {
2641 checkNonCyclicInternal(pos, t);
2642 }
2643
2644
2645 void checkNonCyclic(DiagnosticPosition pos, TypeVar t) {
2646 checkNonCyclic1(pos, t, List.nil());
2647 }
2648
2649 private void checkNonCyclic1(DiagnosticPosition pos, Type t, List<TypeVar> seen) {
2650 final TypeVar tv;
2651 if (t.hasTag(TYPEVAR) && (t.tsym.flags() & UNATTRIBUTED) != 0)
2652 return;
2653 if (seen.contains(t)) {
2654 tv = (TypeVar)t;
2655 tv.setUpperBound(types.createErrorType(t));
2656 log.error(pos, Errors.CyclicInheritance(t));
2657 } else if (t.hasTag(TYPEVAR)) {
2658 tv = (TypeVar)t;
2659 seen = seen.prepend(tv);
2660 for (Type b : types.getBounds(tv))
2661 checkNonCyclic1(pos, b, seen);
2662 }
2663 }
2664
2665 /** Check for cyclic references. Issue an error if the
2666 * symbol of the type referred to has a LOCKED flag set.
2667 *
2668 * @param pos Position to be used for error reporting.
2669 * @param t The type referred to.
2670 * @returns True if the check completed on all attributed classes
2671 */
2672 private boolean checkNonCyclicInternal(DiagnosticPosition pos, Type t) {
2673 boolean complete = true; // was the check complete?
2674 //- System.err.println("checkNonCyclicInternal("+t+");");//DEBUG
2675 Symbol c = t.tsym;
2676 if ((c.flags_field & ACYCLIC) != 0) return true;
2677
2678 if ((c.flags_field & LOCKED) != 0) {
2679 noteCyclic(pos, (ClassSymbol)c);
2680 } else if (!c.type.isErroneous()) {
2681 try {
2682 c.flags_field |= LOCKED;
2683 if (c.type.hasTag(CLASS)) {
2684 ClassType clazz = (ClassType)c.type;
2685 if (clazz.interfaces_field != null)
2686 for (List<Type> l=clazz.interfaces_field; l.nonEmpty(); l=l.tail)
2687 complete &= checkNonCyclicInternal(pos, l.head);
2688 if (clazz.supertype_field != null) {
2689 Type st = clazz.supertype_field;
2690 if (st != null && st.hasTag(CLASS))
2691 complete &= checkNonCyclicInternal(pos, st);
2692 }
2693 if (c.owner.kind == TYP)
2694 complete &= checkNonCyclicInternal(pos, c.owner.type);
2695 }
2696 } finally {
2697 c.flags_field &= ~LOCKED;
2698 }
2699 }
2700 if (complete)
2701 complete = ((c.flags_field & UNATTRIBUTED) == 0) && c.isCompleted();
2702 if (complete) c.flags_field |= ACYCLIC;
2703 return complete;
2704 }
2705
2706 /** Note that we found an inheritance cycle. */
2707 private void noteCyclic(DiagnosticPosition pos, ClassSymbol c) {
2708 log.error(pos, Errors.CyclicInheritance(c));
2709 for (List<Type> l=types.interfaces(c.type); l.nonEmpty(); l=l.tail)
2710 l.head = types.createErrorType((ClassSymbol)l.head.tsym, Type.noType);
2711 Type st = types.supertype(c.type);
2712 if (st.hasTag(CLASS))
2713 ((ClassType)c.type).supertype_field = types.createErrorType((ClassSymbol)st.tsym, Type.noType);
2714 c.type = types.createErrorType(c, c.type);
2715 c.flags_field |= ACYCLIC;
2716 }
2717
2718 /** Check that all methods which implement some
2719 * method conform to the method they implement.
2720 * @param tree The class definition whose members are checked.
2721 */
2722 void checkImplementations(JCClassDecl tree) {
2723 checkImplementations(tree, tree.sym, tree.sym);
2724 }
2725 //where
2726 /** Check that all methods which implement some
2727 * method in `ic' conform to the method they implement.
2728 */
2729 void checkImplementations(JCTree tree, ClassSymbol origin, ClassSymbol ic) {
2730 for (List<Type> l = types.closure(ic.type); l.nonEmpty(); l = l.tail) {
2731 ClassSymbol lc = (ClassSymbol)l.head.tsym;
2732 if ((lc.flags() & ABSTRACT) != 0) {
2733 for (Symbol sym : lc.members().getSymbols(NON_RECURSIVE)) {
2734 if (sym.kind == MTH &&
2735 (sym.flags() & (STATIC|ABSTRACT)) == ABSTRACT) {
2736 MethodSymbol absmeth = (MethodSymbol)sym;
2737 MethodSymbol implmeth = absmeth.implementation(origin, types, false);
2738 if (implmeth != null && implmeth != absmeth &&
2739 (implmeth.owner.flags() & INTERFACE) ==
2740 (origin.flags() & INTERFACE)) {
2741 // don't check if implmeth is in a class, yet
2742 // origin is an interface. This case arises only
2743 // if implmeth is declared in Object. The reason is
2744 // that interfaces really don't inherit from
2745 // Object it's just that the compiler represents
2746 // things that way.
2747 checkOverride(tree, implmeth, absmeth, origin);
2748 }
2749 }
2750 }
2751 }
2752 }
2753 }
2754
2755 /** Check that all abstract methods implemented by a class are
2756 * mutually compatible.
2757 * @param pos Position to be used for error reporting.
2758 * @param c The class whose interfaces are checked.
2759 */
2760 void checkCompatibleSupertypes(DiagnosticPosition pos, Type c) {
2761 List<Type> supertypes = types.interfaces(c);
2762 Type supertype = types.supertype(c);
2763 if (supertype.hasTag(CLASS) &&
2764 (supertype.tsym.flags() & ABSTRACT) != 0)
2765 supertypes = supertypes.prepend(supertype);
2766 for (List<Type> l = supertypes; l.nonEmpty(); l = l.tail) {
2767 if (!l.head.getTypeArguments().isEmpty() &&
2768 !checkCompatibleAbstracts(pos, l.head, l.head, c))
2769 return;
2770 for (List<Type> m = supertypes; m != l; m = m.tail)
2771 if (!checkCompatibleAbstracts(pos, l.head, m.head, c))
2772 return;
2773 }
2774 checkCompatibleConcretes(pos, c);
2775
2776 boolean cIsValue = (c.tsym.flags() & VALUE_CLASS) != 0;
2777 boolean cHasIdentity = (c.tsym.flags() & IDENTITY_TYPE) != 0;
2778 Type identitySuper = null, valueSuper = null;
2779 for (Type t : types.closure(c)) {
2780 if (t != c) {
2781 if ((t.tsym.flags() & IDENTITY_TYPE) != 0)
2782 identitySuper = t;
2783 else if ((t.tsym.flags() & VALUE_CLASS) != 0)
2784 valueSuper = t;
2785 if (cIsValue && identitySuper != null) {
2786 log.error(pos, Errors.ValueTypeHasIdentitySuperType(c, identitySuper));
2787 break;
2788 } else if (cHasIdentity && valueSuper != null) {
2789 log.error(pos, Errors.IdentityTypeHasValueSuperType(c, valueSuper));
2790 break;
2791 } else if (identitySuper != null && valueSuper != null) {
2792 log.error(pos, Errors.MutuallyIncompatibleSupers(c, identitySuper, valueSuper));
2793 break;
2794 }
2795 }
2796 }
2797 }
2798
2799 /** Check that all non-override equivalent methods accessible from 'site'
2800 * are mutually compatible (JLS 8.4.8/9.4.1).
2801 *
2802 * @param pos Position to be used for error reporting.
2803 * @param site The class whose methods are checked.
2804 * @param sym The method symbol to be checked.
2805 */
2806 void checkOverrideClashes(DiagnosticPosition pos, Type site, MethodSymbol sym) {
2807 ClashFilter cf = new ClashFilter(site);
2808 //for each method m1 that is overridden (directly or indirectly)
2809 //by method 'sym' in 'site'...
2810
2811 List<MethodSymbol> potentiallyAmbiguousList = List.nil();
2812 boolean overridesAny = false;
2813 ArrayList<Symbol> symbolsByName = new ArrayList<>();
2814 types.membersClosure(site, false).getSymbolsByName(sym.name, cf).forEach(symbolsByName::add);
2815 for (Symbol m1 : symbolsByName) {
2816 if (!sym.overrides(m1, site.tsym, types, false)) {
2817 if (m1 == sym) {
2818 continue;
2819 }
2820
2821 if (!overridesAny) {
2822 potentiallyAmbiguousList = potentiallyAmbiguousList.prepend((MethodSymbol)m1);
2823 }
2824 continue;
2825 }
2826
2827 if (m1 != sym) {
2828 overridesAny = true;
2829 potentiallyAmbiguousList = List.nil();
2830 }
2831
2832 //...check each method m2 that is a member of 'site'
2833 for (Symbol m2 : symbolsByName) {
2834 if (m2 == m1) continue;
2835 //if (i) the signature of 'sym' is not a subsignature of m1 (seen as
2836 //a member of 'site') and (ii) m1 has the same erasure as m2, issue an error
2837 if (!types.isSubSignature(sym.type, types.memberType(site, m2)) &&
2838 types.hasSameArgs(m2.erasure(types), m1.erasure(types))) {
2839 sym.flags_field |= CLASH;
2840 if (m1 == sym) {
2841 log.error(pos, Errors.NameClashSameErasureNoOverride(
2842 m1.name, types.memberType(site, m1).asMethodType().getParameterTypes(), m1.location(),
2843 m2.name, types.memberType(site, m2).asMethodType().getParameterTypes(), m2.location()));
2844 } else {
2845 ClassType ct = (ClassType)site;
2846 String kind = ct.isInterface() ? "interface" : "class";
2847 log.error(pos, Errors.NameClashSameErasureNoOverride1(
2848 kind,
2849 ct.tsym.name,
2850 m1.name,
2851 types.memberType(site, m1).asMethodType().getParameterTypes(),
2852 m1.location(),
2853 m2.name,
2854 types.memberType(site, m2).asMethodType().getParameterTypes(),
2855 m2.location()));
2856 }
2857 return;
2858 }
2859 }
2860 }
2861
2862 if (!overridesAny) {
2863 for (MethodSymbol m: potentiallyAmbiguousList) {
2864 checkPotentiallyAmbiguousOverloads(pos, site, sym, m);
2865 }
2866 }
2867 }
2868
2869 /** Check that all static methods accessible from 'site' are
2870 * mutually compatible (JLS 8.4.8).
2871 *
2872 * @param pos Position to be used for error reporting.
2873 * @param site The class whose methods are checked.
2874 * @param sym The method symbol to be checked.
2875 */
2876 void checkHideClashes(DiagnosticPosition pos, Type site, MethodSymbol sym) {
2877 ClashFilter cf = new ClashFilter(site);
2878 //for each method m1 that is a member of 'site'...
2879 for (Symbol s : types.membersClosure(site, true).getSymbolsByName(sym.name, cf)) {
2880 //if (i) the signature of 'sym' is not a subsignature of m1 (seen as
2881 //a member of 'site') and (ii) 'sym' has the same erasure as m1, issue an error
2882 if (!types.isSubSignature(sym.type, types.memberType(site, s))) {
2883 if (types.hasSameArgs(s.erasure(types), sym.erasure(types))) {
2884 log.error(pos,
2885 Errors.NameClashSameErasureNoHide(sym, sym.location(), s, s.location()));
2886 return;
2887 } else {
2888 checkPotentiallyAmbiguousOverloads(pos, site, sym, (MethodSymbol)s);
2889 }
2890 }
2891 }
2892 }
2893
2894 //where
2895 private class ClashFilter implements Predicate<Symbol> {
2896
2897 Type site;
2898
2899 ClashFilter(Type site) {
2900 this.site = site;
2901 }
2902
2903 boolean shouldSkip(Symbol s) {
2904 return (s.flags() & CLASH) != 0 &&
2905 s.owner == site.tsym;
2906 }
2907
2908 @Override
2909 public boolean test(Symbol s) {
2910 return s.kind == MTH &&
2911 (s.flags() & SYNTHETIC) == 0 &&
2912 !shouldSkip(s) &&
2913 s.isInheritedIn(site.tsym, types) &&
2914 !s.isInitOrVNew();
2915 }
2916 }
2917
2918 void checkDefaultMethodClashes(DiagnosticPosition pos, Type site) {
2919 DefaultMethodClashFilter dcf = new DefaultMethodClashFilter(site);
2920 for (Symbol m : types.membersClosure(site, false).getSymbols(dcf)) {
2921 Assert.check(m.kind == MTH);
2922 List<MethodSymbol> prov = types.interfaceCandidates(site, (MethodSymbol)m);
2923 if (prov.size() > 1) {
2924 ListBuffer<Symbol> abstracts = new ListBuffer<>();
2925 ListBuffer<Symbol> defaults = new ListBuffer<>();
2926 for (MethodSymbol provSym : prov) {
2927 if ((provSym.flags() & DEFAULT) != 0) {
2928 defaults = defaults.append(provSym);
2929 } else if ((provSym.flags() & ABSTRACT) != 0) {
2930 abstracts = abstracts.append(provSym);
2931 }
2932 if (defaults.nonEmpty() && defaults.size() + abstracts.size() >= 2) {
2933 //strong semantics - issue an error if two sibling interfaces
2934 //have two override-equivalent defaults - or if one is abstract
2935 //and the other is default
2936 Fragment diagKey;
2937 Symbol s1 = defaults.first();
2938 Symbol s2;
2939 if (defaults.size() > 1) {
2940 s2 = defaults.toList().tail.head;
2941 diagKey = Fragments.IncompatibleUnrelatedDefaults(Kinds.kindName(site.tsym), site,
2942 m.name, types.memberType(site, m).getParameterTypes(),
2943 s1.location(), s2.location());
2944
2945 } else {
2946 s2 = abstracts.first();
2947 diagKey = Fragments.IncompatibleAbstractDefault(Kinds.kindName(site.tsym), site,
2948 m.name, types.memberType(site, m).getParameterTypes(),
2949 s1.location(), s2.location());
2950 }
2951 log.error(pos, Errors.TypesIncompatible(s1.location().type, s2.location().type, diagKey));
2952 break;
2953 }
2954 }
2955 }
2956 }
2957 }
2958
2959 //where
2960 private class DefaultMethodClashFilter implements Predicate<Symbol> {
2961
2962 Type site;
2963
2964 DefaultMethodClashFilter(Type site) {
2965 this.site = site;
2966 }
2967
2968 @Override
2969 public boolean test(Symbol s) {
2970 return s.kind == MTH &&
2971 (s.flags() & DEFAULT) != 0 &&
2972 s.isInheritedIn(site.tsym, types) &&
2973 !s.isInitOrVNew();
2974 }
2975 }
2976
2977 /**
2978 * Report warnings for potentially ambiguous method declarations. Two declarations
2979 * are potentially ambiguous if they feature two unrelated functional interface
2980 * in same argument position (in which case, a call site passing an implicit
2981 * lambda would be ambiguous).
2982 */
2983 void checkPotentiallyAmbiguousOverloads(DiagnosticPosition pos, Type site,
2984 MethodSymbol msym1, MethodSymbol msym2) {
2985 if (msym1 != msym2 &&
2986 lint.isEnabled(LintCategory.OVERLOADS) &&
2987 (msym1.flags() & POTENTIALLY_AMBIGUOUS) == 0 &&
2988 (msym2.flags() & POTENTIALLY_AMBIGUOUS) == 0) {
2989 Type mt1 = types.memberType(site, msym1);
2990 Type mt2 = types.memberType(site, msym2);
2991 //if both generic methods, adjust type variables
2992 if (mt1.hasTag(FORALL) && mt2.hasTag(FORALL) &&
2993 types.hasSameBounds((ForAll)mt1, (ForAll)mt2)) {
2994 mt2 = types.subst(mt2, ((ForAll)mt2).tvars, ((ForAll)mt1).tvars);
2995 }
2996 //expand varargs methods if needed
2997 int maxLength = Math.max(mt1.getParameterTypes().length(), mt2.getParameterTypes().length());
2998 List<Type> args1 = rs.adjustArgs(mt1.getParameterTypes(), msym1, maxLength, true);
2999 List<Type> args2 = rs.adjustArgs(mt2.getParameterTypes(), msym2, maxLength, true);
3000 //if arities don't match, exit
3001 if (args1.length() != args2.length()) return;
3002 boolean potentiallyAmbiguous = false;
3003 while (args1.nonEmpty() && args2.nonEmpty()) {
3004 Type s = args1.head;
3005 Type t = args2.head;
3006 if (!types.isSubtype(t, s) && !types.isSubtype(s, t)) {
3007 if (types.isFunctionalInterface(s) && types.isFunctionalInterface(t) &&
3008 types.findDescriptorType(s).getParameterTypes().length() > 0 &&
3009 types.findDescriptorType(s).getParameterTypes().length() ==
3010 types.findDescriptorType(t).getParameterTypes().length()) {
3011 potentiallyAmbiguous = true;
3012 } else {
3013 return;
3014 }
3015 }
3016 args1 = args1.tail;
3017 args2 = args2.tail;
3018 }
3019 if (potentiallyAmbiguous) {
3020 //we found two incompatible functional interfaces with same arity
3021 //this means a call site passing an implicit lambda would be ambiguous
3022 msym1.flags_field |= POTENTIALLY_AMBIGUOUS;
3023 msym2.flags_field |= POTENTIALLY_AMBIGUOUS;
3024 log.warning(LintCategory.OVERLOADS, pos,
3025 Warnings.PotentiallyAmbiguousOverload(msym1, msym1.location(),
3026 msym2, msym2.location()));
3027 return;
3028 }
3029 }
3030 }
3031
3032 void checkAccessFromSerializableElement(final JCTree tree, boolean isLambda) {
3033 if (warnOnAnyAccessToMembers ||
3034 (lint.isEnabled(LintCategory.SERIAL) &&
3035 !lint.isSuppressed(LintCategory.SERIAL) &&
3036 isLambda)) {
3037 Symbol sym = TreeInfo.symbol(tree);
3038 if (!sym.kind.matches(KindSelector.VAL_MTH)) {
3039 return;
3040 }
3041
3042 if (sym.kind == VAR) {
3043 if ((sym.flags() & PARAMETER) != 0 ||
3044 sym.isDirectlyOrIndirectlyLocal() ||
3045 sym.name == names._this ||
3046 sym.name == names._super) {
3047 return;
3048 }
3049 }
3050
3051 if (!types.isSubtype(sym.owner.type, syms.serializableType) &&
3052 isEffectivelyNonPublic(sym)) {
3053 if (isLambda) {
3054 if (belongsToRestrictedPackage(sym)) {
3055 log.warning(LintCategory.SERIAL, tree.pos(),
3056 Warnings.AccessToMemberFromSerializableLambda(sym));
3057 }
3058 } else {
3059 log.warning(tree.pos(),
3060 Warnings.AccessToMemberFromSerializableElement(sym));
3061 }
3062 }
3063 }
3064 }
3065
3066 private boolean isEffectivelyNonPublic(Symbol sym) {
3067 if (sym.packge() == syms.rootPackage) {
3068 return false;
3069 }
3070
3071 while (sym.kind != PCK) {
3072 if ((sym.flags() & PUBLIC) == 0) {
3073 return true;
3074 }
3075 sym = sym.owner;
3076 }
3077 return false;
3078 }
3079
3080 private boolean belongsToRestrictedPackage(Symbol sym) {
3081 String fullName = sym.packge().fullname.toString();
3082 return fullName.startsWith("java.") ||
3083 fullName.startsWith("javax.") ||
3084 fullName.startsWith("sun.") ||
3085 fullName.contains(".internal.");
3086 }
3087
3088 /** Check that class c does not implement directly or indirectly
3089 * the same parameterized interface with two different argument lists.
3090 * @param pos Position to be used for error reporting.
3091 * @param type The type whose interfaces are checked.
3092 */
3093 void checkClassBounds(DiagnosticPosition pos, Type type) {
3094 checkClassBounds(pos, new HashMap<TypeSymbol,Type>(), type);
3095 }
3096 //where
3097 /** Enter all interfaces of type `type' into the hash table `seensofar'
3098 * with their class symbol as key and their type as value. Make
3099 * sure no class is entered with two different types.
3100 */
3101 void checkClassBounds(DiagnosticPosition pos,
3102 Map<TypeSymbol,Type> seensofar,
3103 Type type) {
3104 if (type.isErroneous()) return;
3105 for (List<Type> l = types.interfaces(type); l.nonEmpty(); l = l.tail) {
3106 Type it = l.head;
3107 if (type.hasTag(CLASS) && !it.hasTag(CLASS)) continue; // JLS 8.1.5
3108
3109 Type oldit = seensofar.put(it.tsym, it);
3110 if (oldit != null) {
3111 List<Type> oldparams = oldit.allparams();
3112 List<Type> newparams = it.allparams();
3113 if (!types.containsTypeEquivalent(oldparams, newparams))
3114 log.error(pos,
3115 Errors.CantInheritDiffArg(it.tsym,
3116 Type.toString(oldparams),
3117 Type.toString(newparams)));
3118 }
3119 checkClassBounds(pos, seensofar, it);
3120 }
3121 Type st = types.supertype(type);
3122 if (type.hasTag(CLASS) && !st.hasTag(CLASS)) return; // JLS 8.1.4
3123 if (st != Type.noType) checkClassBounds(pos, seensofar, st);
3124 }
3125
3126 /** Enter interface into into set.
3127 * If it existed already, issue a "repeated interface" error.
3128 */
3129 void checkNotRepeated(DiagnosticPosition pos, Type it, Set<Type> its) {
3130 if (its.contains(it))
3131 log.error(pos, Errors.RepeatedInterface);
3132 else {
3133 its.add(it);
3134 }
3135 }
3136
3137 /* *************************************************************************
3138 * Check annotations
3139 **************************************************************************/
3140
3141 /**
3142 * Recursively validate annotations values
3143 */
3144 void validateAnnotationTree(JCTree tree) {
3145 class AnnotationValidator extends TreeScanner {
3146 @Override
3147 public void visitAnnotation(JCAnnotation tree) {
3148 if (!tree.type.isErroneous() && tree.type.tsym.isAnnotationType()) {
3149 super.visitAnnotation(tree);
3150 validateAnnotation(tree);
3151 }
3152 }
3153 }
3154 tree.accept(new AnnotationValidator());
3155 }
3156
3157 /**
3158 * {@literal
3159 * Annotation types are restricted to primitives, String, an
3160 * enum, an annotation, Class, Class<?>, Class<? extends
3161 * Anything>, arrays of the preceding.
3162 * }
3163 */
3164 void validateAnnotationType(JCTree restype) {
3165 // restype may be null if an error occurred, so don't bother validating it
3166 if (restype != null) {
3167 validateAnnotationType(restype.pos(), restype.type);
3168 }
3169 }
3170
3171 void validateAnnotationType(DiagnosticPosition pos, Type type) {
3172 if (type.isPrimitive()) return;
3173 if (types.isSameType(type, syms.stringType)) return;
3174 if ((type.tsym.flags() & Flags.ENUM) != 0) return;
3175 if ((type.tsym.flags() & Flags.ANNOTATION) != 0) return;
3176 if (types.cvarLowerBound(type).tsym == syms.classType.tsym) return;
3177 if (types.isArray(type) && !types.isArray(types.elemtype(type))) {
3178 validateAnnotationType(pos, types.elemtype(type));
3179 return;
3180 }
3181 log.error(pos, Errors.InvalidAnnotationMemberType);
3182 }
3183
3184 /**
3185 * "It is also a compile-time error if any method declared in an
3186 * annotation type has a signature that is override-equivalent to
3187 * that of any public or protected method declared in class Object
3188 * or in the interface annotation.Annotation."
3189 *
3190 * @jls 9.6 Annotation Types
3191 */
3192 void validateAnnotationMethod(DiagnosticPosition pos, MethodSymbol m) {
3193 for (Type sup = syms.annotationType; sup.hasTag(CLASS); sup = types.supertype(sup)) {
3194 Scope s = sup.tsym.members();
3195 for (Symbol sym : s.getSymbolsByName(m.name)) {
3196 if (sym.kind == MTH &&
3197 (sym.flags() & (PUBLIC | PROTECTED)) != 0 &&
3198 types.overrideEquivalent(m.type, sym.type))
3199 log.error(pos, Errors.IntfAnnotationMemberClash(sym, sup));
3200 }
3201 }
3202 }
3203
3204 /** Check the annotations of a symbol.
3205 */
3206 public void validateAnnotations(List<JCAnnotation> annotations, JCTree declarationTree, Symbol s) {
3207 for (JCAnnotation a : annotations)
3208 validateAnnotation(a, declarationTree, s);
3209 }
3210
3211 /** Check the type annotations.
3212 */
3213 public void validateTypeAnnotations(List<JCAnnotation> annotations, boolean isTypeParameter) {
3214 for (JCAnnotation a : annotations)
3215 validateTypeAnnotation(a, isTypeParameter);
3216 }
3217
3218 /** Check an annotation of a symbol.
3219 */
3220 private void validateAnnotation(JCAnnotation a, JCTree declarationTree, Symbol s) {
3221 /** NOTE: if annotation processors are present, annotation processing rounds can happen after this method,
3222 * this can impact in particular records for which annotations are forcibly propagated.
3223 */
3224 validateAnnotationTree(a);
3225 boolean isRecordMember = ((s.flags_field & RECORD) != 0 || s.enclClass() != null && s.enclClass().isRecord());
3226
3227 boolean isRecordField = (s.flags_field & RECORD) != 0 &&
3228 declarationTree.hasTag(VARDEF) &&
3229 s.owner.kind == TYP;
3230
3231 if (isRecordField) {
3232 // first we need to check if the annotation is applicable to records
3233 Name[] targets = getTargetNames(a);
3234 boolean appliesToRecords = false;
3235 for (Name target : targets) {
3236 appliesToRecords =
3237 target == names.FIELD ||
3238 target == names.PARAMETER ||
3239 target == names.METHOD ||
3240 target == names.TYPE_USE ||
3241 target == names.RECORD_COMPONENT;
3242 if (appliesToRecords) {
3243 break;
3244 }
3245 }
3246 if (!appliesToRecords) {
3247 log.error(a.pos(), Errors.AnnotationTypeNotApplicable);
3248 } else {
3249 /* lets now find the annotations in the field that are targeted to record components and append them to
3250 * the corresponding record component
3251 */
3252 ClassSymbol recordClass = (ClassSymbol) s.owner;
3253 RecordComponent rc = recordClass.getRecordComponent((VarSymbol)s);
3254 SymbolMetadata metadata = rc.getMetadata();
3255 if (metadata == null || metadata.isEmpty()) {
3256 /* if not is empty then we have already been here, which is the case if multiple annotations are applied
3257 * to the record component declaration
3258 */
3259 rc.appendAttributes(s.getRawAttributes().stream().filter(anno ->
3260 Arrays.stream(getTargetNames(anno.type.tsym)).anyMatch(name -> name == names.RECORD_COMPONENT)
3261 ).collect(List.collector()));
3262
3263 JCVariableDecl fieldAST = (JCVariableDecl) declarationTree;
3264 for (JCAnnotation fieldAnnot : fieldAST.mods.annotations) {
3265 for (JCAnnotation rcAnnot : rc.declarationFor().mods.annotations) {
3266 if (rcAnnot.pos == fieldAnnot.pos) {
3267 rcAnnot.setType(fieldAnnot.type);
3268 break;
3269 }
3270 }
3271 }
3272
3273 /* At this point, we used to carry over any type annotations from the VARDEF to the record component, but
3274 * that is problematic, since we get here only when *some* annotation is applied to the SE5 (declaration)
3275 * annotation location, inadvertently failing to carry over the type annotations when the VarDef has no
3276 * annotations in the SE5 annotation location.
3277 *
3278 * Now type annotations are assigned to record components in a method that would execute irrespective of
3279 * whether there are SE5 annotations on a VarDef viz com.sun.tools.javac.code.TypeAnnotations.TypeAnnotationPositions.visitVarDef
3280 */
3281 }
3282 }
3283 }
3284
3285 /* the section below is tricky. Annotations applied to record components are propagated to the corresponding
3286 * record member so if an annotation has target: FIELD, it is propagated to the corresponding FIELD, if it has
3287 * target METHOD, it is propagated to the accessor and so on. But at the moment when method members are generated
3288 * there is no enough information to propagate only the right annotations. So all the annotations are propagated
3289 * to all the possible locations.
3290 *
3291 * At this point we need to remove all the annotations that are not in place before going on with the annotation
3292 * party. On top of the above there is the issue that there is no AST representing record components, just symbols
3293 * so the corresponding field has been holding all the annotations and it's metadata has been modified as if it
3294 * was both a field and a record component.
3295 *
3296 * So there are two places where we need to trim annotations from: the metadata of the symbol and / or the modifiers
3297 * in the AST. Whatever is in the metadata will be written to the class file, whatever is in the modifiers could
3298 * be see by annotation processors.
3299 *
3300 * The metadata contains both type annotations and declaration annotations. At this point of the game we don't
3301 * need to care about type annotations, they are all in the right place. But we could need to remove declaration
3302 * annotations. So for declaration annotations if they are not applicable to the record member, excluding type
3303 * annotations which are already correct, then we will remove it. For the AST modifiers if the annotation is not
3304 * applicable either as type annotation and or declaration annotation, only in that case it will be removed.
3305 *
3306 * So it could be that annotation is removed as a declaration annotation but it is kept in the AST modifier for
3307 * further inspection by annotation processors.
3308 *
3309 * For example:
3310 *
3311 * import java.lang.annotation.*;
3312 *
3313 * @Target({ElementType.TYPE_USE, ElementType.RECORD_COMPONENT})
3314 * @Retention(RetentionPolicy.RUNTIME)
3315 * @interface Anno { }
3316 *
3317 * record R(@Anno String s) {}
3318 *
3319 * at this point we will have for the case of the generated field:
3320 * - @Anno in the modifier
3321 * - @Anno as a type annotation
3322 * - @Anno as a declaration annotation
3323 *
3324 * the last one should be removed because the annotation has not FIELD as target but it was applied as a
3325 * declaration annotation because the field was being treated both as a field and as a record component
3326 * as we have already copied the annotations to the record component, now the field doesn't need to hold
3327 * annotations that are not intended for it anymore. Still @Anno has to be kept in the AST's modifiers as it
3328 * is applicable as a type annotation to the type of the field.
3329 */
3330
3331 if (a.type.tsym.isAnnotationType()) {
3332 Optional<Set<Name>> applicableTargetsOp = getApplicableTargets(a, s);
3333 if (!applicableTargetsOp.isEmpty()) {
3334 Set<Name> applicableTargets = applicableTargetsOp.get();
3335 boolean notApplicableOrIsTypeUseOnly = applicableTargets.isEmpty() ||
3336 applicableTargets.size() == 1 && applicableTargets.contains(names.TYPE_USE);
3337 boolean isCompGeneratedRecordElement = isRecordMember && (s.flags_field & Flags.GENERATED_MEMBER) != 0;
3338 boolean isCompRecordElementWithNonApplicableDeclAnno = isCompGeneratedRecordElement && notApplicableOrIsTypeUseOnly;
3339
3340 if (applicableTargets.isEmpty() || isCompRecordElementWithNonApplicableDeclAnno) {
3341 if (isCompRecordElementWithNonApplicableDeclAnno) {
3342 /* so we have found an annotation that is not applicable to a record member that was generated by the
3343 * compiler. This was intentionally done at TypeEnter, now is the moment strip away the annotations
3344 * that are not applicable to the given record member
3345 */
3346 JCModifiers modifiers = TreeInfo.getModifiers(declarationTree);
3347 /* lets first remove the annotation from the modifier if it is not applicable, we have to check again as
3348 * it could be a type annotation
3349 */
3350 if (modifiers != null && applicableTargets.isEmpty()) {
3351 ListBuffer<JCAnnotation> newAnnotations = new ListBuffer<>();
3352 for (JCAnnotation anno : modifiers.annotations) {
3353 if (anno != a) {
3354 newAnnotations.add(anno);
3355 }
3356 }
3357 modifiers.annotations = newAnnotations.toList();
3358 }
3359 // now lets remove it from the symbol
3360 s.getMetadata().removeDeclarationMetadata(a.attribute);
3361 } else {
3362 log.error(a.pos(), Errors.AnnotationTypeNotApplicable);
3363 }
3364 }
3365 /* if we are seeing the @SafeVarargs annotation applied to a compiler generated accessor,
3366 * then this is an error as we know that no compiler generated accessor will be a varargs
3367 * method, better to fail asap
3368 */
3369 if (isCompGeneratedRecordElement && !isRecordField && a.type.tsym == syms.trustMeType.tsym && declarationTree.hasTag(METHODDEF)) {
3370 log.error(a.pos(), Errors.VarargsInvalidTrustmeAnno(syms.trustMeType.tsym, Fragments.VarargsTrustmeOnNonVarargsAccessor(s)));
3371 }
3372 }
3373 }
3374
3375 if (a.annotationType.type.tsym == syms.functionalInterfaceType.tsym) {
3376 if (s.kind != TYP) {
3377 log.error(a.pos(), Errors.BadFunctionalIntfAnno);
3378 } else if (!s.isInterface() || (s.flags() & ANNOTATION) != 0) {
3379 log.error(a.pos(), Errors.BadFunctionalIntfAnno1(Fragments.NotAFunctionalIntf(s)));
3380 }
3381 }
3382 }
3383
3384 public void validateTypeAnnotation(JCAnnotation a, boolean isTypeParameter) {
3385 Assert.checkNonNull(a.type);
3386 validateAnnotationTree(a);
3387
3388 if (a.hasTag(TYPE_ANNOTATION) &&
3389 !a.annotationType.type.isErroneous() &&
3390 !isTypeAnnotation(a, isTypeParameter)) {
3391 log.error(a.pos(), Errors.AnnotationTypeNotApplicableToType(a.type));
3392 }
3393 }
3394
3395 /**
3396 * Validate the proposed container 'repeatable' on the
3397 * annotation type symbol 's'. Report errors at position
3398 * 'pos'.
3399 *
3400 * @param s The (annotation)type declaration annotated with a @Repeatable
3401 * @param repeatable the @Repeatable on 's'
3402 * @param pos where to report errors
3403 */
3404 public void validateRepeatable(TypeSymbol s, Attribute.Compound repeatable, DiagnosticPosition pos) {
3405 Assert.check(types.isSameType(repeatable.type, syms.repeatableType));
3406
3407 Type t = null;
3408 List<Pair<MethodSymbol,Attribute>> l = repeatable.values;
3409 if (!l.isEmpty()) {
3410 Assert.check(l.head.fst.name == names.value);
3411 if (l.head.snd instanceof Attribute.Class) {
3412 t = ((Attribute.Class)l.head.snd).getValue();
3413 }
3414 }
3415
3416 if (t == null) {
3417 // errors should already have been reported during Annotate
3418 return;
3419 }
3420
3421 validateValue(t.tsym, s, pos);
3422 validateRetention(t.tsym, s, pos);
3423 validateDocumented(t.tsym, s, pos);
3424 validateInherited(t.tsym, s, pos);
3425 validateTarget(t.tsym, s, pos);
3426 validateDefault(t.tsym, pos);
3427 }
3428
3429 private void validateValue(TypeSymbol container, TypeSymbol contained, DiagnosticPosition pos) {
3430 Symbol sym = container.members().findFirst(names.value);
3431 if (sym != null && sym.kind == MTH) {
3432 MethodSymbol m = (MethodSymbol) sym;
3433 Type ret = m.getReturnType();
3434 if (!(ret.hasTag(ARRAY) && types.isSameType(((ArrayType)ret).elemtype, contained.type))) {
3435 log.error(pos,
3436 Errors.InvalidRepeatableAnnotationValueReturn(container,
3437 ret,
3438 types.makeArrayType(contained.type)));
3439 }
3440 } else {
3441 log.error(pos, Errors.InvalidRepeatableAnnotationNoValue(container));
3442 }
3443 }
3444
3445 private void validateRetention(TypeSymbol container, TypeSymbol contained, DiagnosticPosition pos) {
3446 Attribute.RetentionPolicy containerRetention = types.getRetention(container);
3447 Attribute.RetentionPolicy containedRetention = types.getRetention(contained);
3448
3449 boolean error = false;
3450 switch (containedRetention) {
3451 case RUNTIME:
3452 if (containerRetention != Attribute.RetentionPolicy.RUNTIME) {
3453 error = true;
3454 }
3455 break;
3456 case CLASS:
3457 if (containerRetention == Attribute.RetentionPolicy.SOURCE) {
3458 error = true;
3459 }
3460 }
3461 if (error ) {
3462 log.error(pos,
3463 Errors.InvalidRepeatableAnnotationRetention(container,
3464 containerRetention.name(),
3465 contained,
3466 containedRetention.name()));
3467 }
3468 }
3469
3470 private void validateDocumented(Symbol container, Symbol contained, DiagnosticPosition pos) {
3471 if (contained.attribute(syms.documentedType.tsym) != null) {
3472 if (container.attribute(syms.documentedType.tsym) == null) {
3473 log.error(pos, Errors.InvalidRepeatableAnnotationNotDocumented(container, contained));
3474 }
3475 }
3476 }
3477
3478 private void validateInherited(Symbol container, Symbol contained, DiagnosticPosition pos) {
3479 if (contained.attribute(syms.inheritedType.tsym) != null) {
3480 if (container.attribute(syms.inheritedType.tsym) == null) {
3481 log.error(pos, Errors.InvalidRepeatableAnnotationNotInherited(container, contained));
3482 }
3483 }
3484 }
3485
3486 private void validateTarget(TypeSymbol container, TypeSymbol contained, DiagnosticPosition pos) {
3487 // The set of targets the container is applicable to must be a subset
3488 // (with respect to annotation target semantics) of the set of targets
3489 // the contained is applicable to. The target sets may be implicit or
3490 // explicit.
3491
3492 Set<Name> containerTargets;
3493 Attribute.Array containerTarget = getAttributeTargetAttribute(container);
3494 if (containerTarget == null) {
3495 containerTargets = getDefaultTargetSet();
3496 } else {
3497 containerTargets = new HashSet<>();
3498 for (Attribute app : containerTarget.values) {
3499 if (!(app instanceof Attribute.Enum attributeEnum)) {
3500 continue; // recovery
3501 }
3502 containerTargets.add(attributeEnum.value.name);
3503 }
3504 }
3505
3506 Set<Name> containedTargets;
3507 Attribute.Array containedTarget = getAttributeTargetAttribute(contained);
3508 if (containedTarget == null) {
3509 containedTargets = getDefaultTargetSet();
3510 } else {
3511 containedTargets = new HashSet<>();
3512 for (Attribute app : containedTarget.values) {
3513 if (!(app instanceof Attribute.Enum attributeEnum)) {
3514 continue; // recovery
3515 }
3516 containedTargets.add(attributeEnum.value.name);
3517 }
3518 }
3519
3520 if (!isTargetSubsetOf(containerTargets, containedTargets)) {
3521 log.error(pos, Errors.InvalidRepeatableAnnotationIncompatibleTarget(container, contained));
3522 }
3523 }
3524
3525 /* get a set of names for the default target */
3526 private Set<Name> getDefaultTargetSet() {
3527 if (defaultTargets == null) {
3528 defaultTargets = Set.of(defaultTargetMetaInfo());
3529 }
3530
3531 return defaultTargets;
3532 }
3533 private Set<Name> defaultTargets;
3534
3535
3536 /** Checks that s is a subset of t, with respect to ElementType
3537 * semantics, specifically {ANNOTATION_TYPE} is a subset of {TYPE},
3538 * and {TYPE_USE} covers the set {ANNOTATION_TYPE, TYPE, TYPE_USE,
3539 * TYPE_PARAMETER}.
3540 */
3541 private boolean isTargetSubsetOf(Set<Name> s, Set<Name> t) {
3542 // Check that all elements in s are present in t
3543 for (Name n2 : s) {
3544 boolean currentElementOk = false;
3545 for (Name n1 : t) {
3546 if (n1 == n2) {
3547 currentElementOk = true;
3548 break;
3549 } else if (n1 == names.TYPE && n2 == names.ANNOTATION_TYPE) {
3550 currentElementOk = true;
3551 break;
3552 } else if (n1 == names.TYPE_USE &&
3553 (n2 == names.TYPE ||
3554 n2 == names.ANNOTATION_TYPE ||
3555 n2 == names.TYPE_PARAMETER)) {
3556 currentElementOk = true;
3557 break;
3558 }
3559 }
3560 if (!currentElementOk)
3561 return false;
3562 }
3563 return true;
3564 }
3565
3566 private void validateDefault(Symbol container, DiagnosticPosition pos) {
3567 // validate that all other elements of containing type has defaults
3568 Scope scope = container.members();
3569 for(Symbol elm : scope.getSymbols()) {
3570 if (elm.name != names.value &&
3571 elm.kind == MTH &&
3572 ((MethodSymbol)elm).defaultValue == null) {
3573 log.error(pos,
3574 Errors.InvalidRepeatableAnnotationElemNondefault(container, elm));
3575 }
3576 }
3577 }
3578
3579 /** Is s a method symbol that overrides a method in a superclass? */
3580 boolean isOverrider(Symbol s) {
3581 if (s.kind != MTH || s.isStatic())
3582 return false;
3583 MethodSymbol m = (MethodSymbol)s;
3584 TypeSymbol owner = (TypeSymbol)m.owner;
3585 for (Type sup : types.closure(owner.type)) {
3586 if (sup == owner.type)
3587 continue; // skip "this"
3588 Scope scope = sup.tsym.members();
3589 for (Symbol sym : scope.getSymbolsByName(m.name)) {
3590 if (!sym.isStatic() && m.overrides(sym, owner, types, true))
3591 return true;
3592 }
3593 }
3594 return false;
3595 }
3596
3597 /** Is the annotation applicable to types? */
3598 protected boolean isTypeAnnotation(JCAnnotation a, boolean isTypeParameter) {
3599 List<Attribute> targets = typeAnnotations.annotationTargets(a.annotationType.type.tsym);
3600 return (targets == null) ?
3601 false :
3602 targets.stream()
3603 .anyMatch(attr -> isTypeAnnotation(attr, isTypeParameter));
3604 }
3605 //where
3606 boolean isTypeAnnotation(Attribute a, boolean isTypeParameter) {
3607 Attribute.Enum e = (Attribute.Enum)a;
3608 return (e.value.name == names.TYPE_USE ||
3609 (isTypeParameter && e.value.name == names.TYPE_PARAMETER));
3610 }
3611
3612 /** Is the annotation applicable to the symbol? */
3613 Name[] getTargetNames(JCAnnotation a) {
3614 return getTargetNames(a.annotationType.type.tsym);
3615 }
3616
3617 public Name[] getTargetNames(TypeSymbol annoSym) {
3618 Attribute.Array arr = getAttributeTargetAttribute(annoSym);
3619 Name[] targets;
3620 if (arr == null) {
3621 targets = defaultTargetMetaInfo();
3622 } else {
3623 // TODO: can we optimize this?
3624 targets = new Name[arr.values.length];
3625 for (int i=0; i<arr.values.length; ++i) {
3626 Attribute app = arr.values[i];
3627 if (!(app instanceof Attribute.Enum attributeEnum)) {
3628 return new Name[0];
3629 }
3630 targets[i] = attributeEnum.value.name;
3631 }
3632 }
3633 return targets;
3634 }
3635
3636 boolean annotationApplicable(JCAnnotation a, Symbol s) {
3637 Optional<Set<Name>> targets = getApplicableTargets(a, s);
3638 /* the optional could be empty if the annotation is unknown in that case
3639 * we return that it is applicable and if it is erroneous that should imply
3640 * an error at the declaration site
3641 */
3642 return targets.isEmpty() || targets.isPresent() && !targets.get().isEmpty();
3643 }
3644
3645 Optional<Set<Name>> getApplicableTargets(JCAnnotation a, Symbol s) {
3646 Attribute.Array arr = getAttributeTargetAttribute(a.annotationType.type.tsym);
3647 Name[] targets;
3648 Set<Name> applicableTargets = new HashSet<>();
3649
3650 if (arr == null) {
3651 targets = defaultTargetMetaInfo();
3652 } else {
3653 // TODO: can we optimize this?
3654 targets = new Name[arr.values.length];
3655 for (int i=0; i<arr.values.length; ++i) {
3656 Attribute app = arr.values[i];
3657 if (!(app instanceof Attribute.Enum attributeEnum)) {
3658 // recovery
3659 return Optional.empty();
3660 }
3661 targets[i] = attributeEnum.value.name;
3662 }
3663 }
3664 for (Name target : targets) {
3665 if (target == names.TYPE) {
3666 if (s.kind == TYP)
3667 applicableTargets.add(names.TYPE);
3668 } else if (target == names.FIELD) {
3669 if (s.kind == VAR && s.owner.kind != MTH)
3670 applicableTargets.add(names.FIELD);
3671 } else if (target == names.RECORD_COMPONENT) {
3672 if (s.getKind() == ElementKind.RECORD_COMPONENT) {
3673 applicableTargets.add(names.RECORD_COMPONENT);
3674 }
3675 } else if (target == names.METHOD) {
3676 if (s.kind == MTH && !s.isInitOrVNew())
3677 applicableTargets.add(names.METHOD);
3678 } else if (target == names.PARAMETER) {
3679 if (s.kind == VAR &&
3680 (s.owner.kind == MTH && (s.flags() & PARAMETER) != 0)) {
3681 applicableTargets.add(names.PARAMETER);
3682 }
3683 } else if (target == names.CONSTRUCTOR) {
3684 if (s.kind == MTH && s.isInitOrVNew())
3685 applicableTargets.add(names.CONSTRUCTOR);
3686 } else if (target == names.LOCAL_VARIABLE) {
3687 if (s.kind == VAR && s.owner.kind == MTH &&
3688 (s.flags() & PARAMETER) == 0) {
3689 applicableTargets.add(names.LOCAL_VARIABLE);
3690 }
3691 } else if (target == names.ANNOTATION_TYPE) {
3692 if (s.kind == TYP && (s.flags() & ANNOTATION) != 0) {
3693 applicableTargets.add(names.ANNOTATION_TYPE);
3694 }
3695 } else if (target == names.PACKAGE) {
3696 if (s.kind == PCK)
3697 applicableTargets.add(names.PACKAGE);
3698 } else if (target == names.TYPE_USE) {
3699 if (s.kind == VAR && s.owner.kind == MTH && s.type.hasTag(NONE)) {
3700 //cannot type annotate implicitly typed locals
3701 continue;
3702 } else if (s.kind == TYP || s.kind == VAR ||
3703 (s.kind == MTH && !s.isInitOrVNew() &&
3704 !s.type.getReturnType().hasTag(VOID)) ||
3705 (s.kind == MTH && s.isInitOrVNew())) {
3706 applicableTargets.add(names.TYPE_USE);
3707 }
3708 } else if (target == names.TYPE_PARAMETER) {
3709 if (s.kind == TYP && s.type.hasTag(TYPEVAR))
3710 applicableTargets.add(names.TYPE_PARAMETER);
3711 } else if (target == names.MODULE) {
3712 if (s.kind == MDL)
3713 applicableTargets.add(names.MODULE);
3714 } else
3715 return Optional.empty(); // Unknown ElementType. This should be an error at declaration site,
3716 // assume applicable.
3717 }
3718 return Optional.of(applicableTargets);
3719 }
3720
3721 Attribute.Array getAttributeTargetAttribute(TypeSymbol s) {
3722 Attribute.Compound atTarget = s.getAnnotationTypeMetadata().getTarget();
3723 if (atTarget == null) return null; // ok, is applicable
3724 Attribute atValue = atTarget.member(names.value);
3725 return (atValue instanceof Attribute.Array attributeArray) ? attributeArray : null;
3726 }
3727
3728 private Name[] dfltTargetMeta;
3729 private Name[] defaultTargetMetaInfo() {
3730 if (dfltTargetMeta == null) {
3731 ArrayList<Name> defaultTargets = new ArrayList<>();
3732 defaultTargets.add(names.PACKAGE);
3733 defaultTargets.add(names.TYPE);
3734 defaultTargets.add(names.FIELD);
3735 defaultTargets.add(names.METHOD);
3736 defaultTargets.add(names.CONSTRUCTOR);
3737 defaultTargets.add(names.ANNOTATION_TYPE);
3738 defaultTargets.add(names.LOCAL_VARIABLE);
3739 defaultTargets.add(names.PARAMETER);
3740 if (allowRecords) {
3741 defaultTargets.add(names.RECORD_COMPONENT);
3742 }
3743 if (allowModules) {
3744 defaultTargets.add(names.MODULE);
3745 }
3746 dfltTargetMeta = defaultTargets.toArray(new Name[0]);
3747 }
3748 return dfltTargetMeta;
3749 }
3750
3751 /** Check an annotation value.
3752 *
3753 * @param a The annotation tree to check
3754 * @return true if this annotation tree is valid, otherwise false
3755 */
3756 public boolean validateAnnotationDeferErrors(JCAnnotation a) {
3757 boolean res = false;
3758 final Log.DiagnosticHandler diagHandler = new Log.DiscardDiagnosticHandler(log);
3759 try {
3760 res = validateAnnotation(a);
3761 } finally {
3762 log.popDiagnosticHandler(diagHandler);
3763 }
3764 return res;
3765 }
3766
3767 private boolean validateAnnotation(JCAnnotation a) {
3768 boolean isValid = true;
3769 AnnotationTypeMetadata metadata = a.annotationType.type.tsym.getAnnotationTypeMetadata();
3770
3771 // collect an inventory of the annotation elements
3772 Set<MethodSymbol> elements = metadata.getAnnotationElements();
3773
3774 // remove the ones that are assigned values
3775 for (JCTree arg : a.args) {
3776 if (!arg.hasTag(ASSIGN)) continue; // recovery
3777 JCAssign assign = (JCAssign)arg;
3778 Symbol m = TreeInfo.symbol(assign.lhs);
3779 if (m == null || m.type.isErroneous()) continue;
3780 if (!elements.remove(m)) {
3781 isValid = false;
3782 log.error(assign.lhs.pos(),
3783 Errors.DuplicateAnnotationMemberValue(m.name, a.type));
3784 }
3785 }
3786
3787 // all the remaining ones better have default values
3788 List<Name> missingDefaults = List.nil();
3789 Set<MethodSymbol> membersWithDefault = metadata.getAnnotationElementsWithDefault();
3790 for (MethodSymbol m : elements) {
3791 if (m.type.isErroneous())
3792 continue;
3793
3794 if (!membersWithDefault.contains(m))
3795 missingDefaults = missingDefaults.append(m.name);
3796 }
3797 missingDefaults = missingDefaults.reverse();
3798 if (missingDefaults.nonEmpty()) {
3799 isValid = false;
3800 Error errorKey = (missingDefaults.size() > 1)
3801 ? Errors.AnnotationMissingDefaultValue1(a.type, missingDefaults)
3802 : Errors.AnnotationMissingDefaultValue(a.type, missingDefaults);
3803 log.error(a.pos(), errorKey);
3804 }
3805
3806 return isValid && validateTargetAnnotationValue(a);
3807 }
3808
3809 /* Validate the special java.lang.annotation.Target annotation */
3810 boolean validateTargetAnnotationValue(JCAnnotation a) {
3811 // special case: java.lang.annotation.Target must not have
3812 // repeated values in its value member
3813 if (a.annotationType.type.tsym != syms.annotationTargetType.tsym ||
3814 a.args.tail == null)
3815 return true;
3816
3817 boolean isValid = true;
3818 if (!a.args.head.hasTag(ASSIGN)) return false; // error recovery
3819 JCAssign assign = (JCAssign) a.args.head;
3820 Symbol m = TreeInfo.symbol(assign.lhs);
3821 if (m.name != names.value) return false;
3822 JCTree rhs = assign.rhs;
3823 if (!rhs.hasTag(NEWARRAY)) return false;
3824 JCNewArray na = (JCNewArray) rhs;
3825 Set<Symbol> targets = new HashSet<>();
3826 for (JCTree elem : na.elems) {
3827 if (!targets.add(TreeInfo.symbol(elem))) {
3828 isValid = false;
3829 log.error(elem.pos(), Errors.RepeatedAnnotationTarget);
3830 }
3831 }
3832 return isValid;
3833 }
3834
3835 void checkDeprecatedAnnotation(DiagnosticPosition pos, Symbol s) {
3836 if (lint.isEnabled(LintCategory.DEP_ANN) && s.isDeprecatableViaAnnotation() &&
3837 (s.flags() & DEPRECATED) != 0 &&
3838 !syms.deprecatedType.isErroneous() &&
3839 s.attribute(syms.deprecatedType.tsym) == null) {
3840 log.warning(LintCategory.DEP_ANN,
3841 pos, Warnings.MissingDeprecatedAnnotation);
3842 }
3843 // Note: @Deprecated has no effect on local variables, parameters and package decls.
3844 if (lint.isEnabled(LintCategory.DEPRECATION) && !s.isDeprecatableViaAnnotation()) {
3845 if (!syms.deprecatedType.isErroneous() && s.attribute(syms.deprecatedType.tsym) != null) {
3846 log.warning(LintCategory.DEPRECATION, pos,
3847 Warnings.DeprecatedAnnotationHasNoEffect(Kinds.kindName(s)));
3848 }
3849 }
3850 }
3851
3852 void checkDeprecated(final DiagnosticPosition pos, final Symbol other, final Symbol s) {
3853 checkDeprecated(() -> pos, other, s);
3854 }
3855
3856 void checkDeprecated(Supplier<DiagnosticPosition> pos, final Symbol other, final Symbol s) {
3857 if ( (s.isDeprecatedForRemoval()
3858 || s.isDeprecated() && !other.isDeprecated())
3859 && (s.outermostClass() != other.outermostClass() || s.outermostClass() == null)
3860 && s.kind != Kind.PCK) {
3861 deferredLintHandler.report(() -> warnDeprecated(pos.get(), s));
3862 }
3863 }
3864
3865 void checkSunAPI(final DiagnosticPosition pos, final Symbol s) {
3866 if ((s.flags() & PROPRIETARY) != 0) {
3867 deferredLintHandler.report(() -> {
3868 log.mandatoryWarning(pos, Warnings.SunProprietary(s));
3869 });
3870 }
3871 }
3872
3873 void checkProfile(final DiagnosticPosition pos, final Symbol s) {
3874 if (profile != Profile.DEFAULT && (s.flags() & NOT_IN_PROFILE) != 0) {
3875 log.error(pos, Errors.NotInProfile(s, profile));
3876 }
3877 }
3878
3879 void checkPreview(DiagnosticPosition pos, Symbol other, Symbol s) {
3880 if ((s.flags() & PREVIEW_API) != 0 && !preview.participatesInPreview(syms, other, s)) {
3881 if ((s.flags() & PREVIEW_REFLECTIVE) == 0) {
3882 if (!preview.isEnabled()) {
3883 log.error(pos, Errors.IsPreview(s));
3884 } else {
3885 preview.markUsesPreview(pos);
3886 deferredLintHandler.report(() -> warnPreviewAPI(pos, Warnings.IsPreview(s)));
3887 }
3888 } else {
3889 deferredLintHandler.report(() -> warnPreviewAPI(pos, Warnings.IsPreviewReflective(s)));
3890 }
3891 }
3892 if (preview.declaredUsingPreviewFeature(s)) {
3893 if (preview.isEnabled()) {
3894 //for preview disabled do presumably so not need to do anything?
3895 //If "s" is compiled from source, then there was an error for it already;
3896 //if "s" is from classfile, there already was an error for the classfile.
3897 preview.markUsesPreview(pos);
3898 deferredLintHandler.report(() -> warnDeclaredUsingPreview(pos, s));
3899 }
3900 }
3901 }
3902
3903 /* *************************************************************************
3904 * Check for recursive annotation elements.
3905 **************************************************************************/
3906
3907 /** Check for cycles in the graph of annotation elements.
3908 */
3909 void checkNonCyclicElements(JCClassDecl tree) {
3910 if ((tree.sym.flags_field & ANNOTATION) == 0) return;
3911 Assert.check((tree.sym.flags_field & LOCKED) == 0);
3912 try {
3913 tree.sym.flags_field |= LOCKED;
3914 for (JCTree def : tree.defs) {
3915 if (!def.hasTag(METHODDEF)) continue;
3916 JCMethodDecl meth = (JCMethodDecl)def;
3917 checkAnnotationResType(meth.pos(), meth.restype.type);
3918 }
3919 } finally {
3920 tree.sym.flags_field &= ~LOCKED;
3921 tree.sym.flags_field |= ACYCLIC_ANN;
3922 }
3923 }
3924
3925 void checkNonCyclicElementsInternal(DiagnosticPosition pos, TypeSymbol tsym) {
3926 if ((tsym.flags_field & ACYCLIC_ANN) != 0)
3927 return;
3928 if ((tsym.flags_field & LOCKED) != 0) {
3929 log.error(pos, Errors.CyclicAnnotationElement(tsym));
3930 return;
3931 }
3932 try {
3933 tsym.flags_field |= LOCKED;
3934 for (Symbol s : tsym.members().getSymbols(NON_RECURSIVE)) {
3935 if (s.kind != MTH)
3936 continue;
3937 checkAnnotationResType(pos, ((MethodSymbol)s).type.getReturnType());
3938 }
3939 } finally {
3940 tsym.flags_field &= ~LOCKED;
3941 tsym.flags_field |= ACYCLIC_ANN;
3942 }
3943 }
3944
3945 void checkAnnotationResType(DiagnosticPosition pos, Type type) {
3946 switch (type.getTag()) {
3947 case CLASS:
3948 if ((type.tsym.flags() & ANNOTATION) != 0)
3949 checkNonCyclicElementsInternal(pos, type.tsym);
3950 break;
3951 case ARRAY:
3952 checkAnnotationResType(pos, types.elemtype(type));
3953 break;
3954 default:
3955 break; // int etc
3956 }
3957 }
3958
3959 /* *************************************************************************
3960 * Check for cycles in the constructor call graph.
3961 **************************************************************************/
3962
3963 /** Check for cycles in the graph of constructors calling other
3964 * constructors.
3965 */
3966 void checkCyclicConstructors(JCClassDecl tree) {
3967 // use LinkedHashMap so we generate errors deterministically
3968 Map<Symbol,Symbol> callMap = new LinkedHashMap<>();
3969
3970 // enter each constructor this-call into the map
3971 for (List<JCTree> l = tree.defs; l.nonEmpty(); l = l.tail) {
3972 JCMethodInvocation app = TreeInfo.firstConstructorCall(l.head);
3973 if (app == null) continue;
3974 JCMethodDecl meth = (JCMethodDecl) l.head;
3975 if (TreeInfo.name(app.meth) == names._this) {
3976 callMap.put(meth.sym, TreeInfo.symbol(app.meth));
3977 } else {
3978 meth.sym.flags_field |= ACYCLIC;
3979 }
3980 }
3981
3982 // Check for cycles in the map
3983 Symbol[] ctors = new Symbol[0];
3984 ctors = callMap.keySet().toArray(ctors);
3985 for (Symbol caller : ctors) {
3986 checkCyclicConstructor(tree, caller, callMap);
3987 }
3988 }
3989
3990 /** Look in the map to see if the given constructor is part of a
3991 * call cycle.
3992 */
3993 private void checkCyclicConstructor(JCClassDecl tree, Symbol ctor,
3994 Map<Symbol,Symbol> callMap) {
3995 if (ctor != null && (ctor.flags_field & ACYCLIC) == 0) {
3996 if ((ctor.flags_field & LOCKED) != 0) {
3997 log.error(TreeInfo.diagnosticPositionFor(ctor, tree, false, t -> t.hasTag(IDENT)),
3998 Errors.RecursiveCtorInvocation);
3999 } else {
4000 ctor.flags_field |= LOCKED;
4001 checkCyclicConstructor(tree, callMap.remove(ctor), callMap);
4002 ctor.flags_field &= ~LOCKED;
4003 }
4004 ctor.flags_field |= ACYCLIC;
4005 }
4006 }
4007
4008 /* *************************************************************************
4009 * Miscellaneous
4010 **************************************************************************/
4011
4012 /**
4013 * Check for division by integer constant zero
4014 * @param pos Position for error reporting.
4015 * @param operator The operator for the expression
4016 * @param operand The right hand operand for the expression
4017 */
4018 void checkDivZero(final DiagnosticPosition pos, Symbol operator, Type operand) {
4019 if (operand.constValue() != null
4020 && operand.getTag().isSubRangeOf(LONG)
4021 && ((Number) (operand.constValue())).longValue() == 0) {
4022 int opc = ((OperatorSymbol)operator).opcode;
4023 if (opc == ByteCodes.idiv || opc == ByteCodes.imod
4024 || opc == ByteCodes.ldiv || opc == ByteCodes.lmod) {
4025 deferredLintHandler.report(() -> warnDivZero(pos));
4026 }
4027 }
4028 }
4029
4030 /**
4031 * Check for possible loss of precission
4032 * @param pos Position for error reporting.
4033 * @param found The computed type of the tree
4034 * @param req The computed type of the tree
4035 */
4036 void checkLossOfPrecision(final DiagnosticPosition pos, Type found, Type req) {
4037 if (found.isNumeric() && req.isNumeric() && !types.isAssignable(found, req)) {
4038 deferredLintHandler.report(() -> {
4039 if (lint.isEnabled(LintCategory.LOSSY_CONVERSIONS))
4040 log.warning(LintCategory.LOSSY_CONVERSIONS,
4041 pos, Warnings.PossibleLossOfPrecision(found, req));
4042 });
4043 }
4044 }
4045
4046 /**
4047 * Check for empty statements after if
4048 */
4049 void checkEmptyIf(JCIf tree) {
4050 if (tree.thenpart.hasTag(SKIP) && tree.elsepart == null &&
4051 lint.isEnabled(LintCategory.EMPTY))
4052 log.warning(LintCategory.EMPTY, tree.thenpart.pos(), Warnings.EmptyIf);
4053 }
4054
4055 /** Check that symbol is unique in given scope.
4056 * @param pos Position for error reporting.
4057 * @param sym The symbol.
4058 * @param s The scope.
4059 */
4060 boolean checkUnique(DiagnosticPosition pos, Symbol sym, Scope s) {
4061 if (sym.type.isErroneous())
4062 return true;
4063 if (sym.owner.name == names.any) return false;
4064 for (Symbol byName : s.getSymbolsByName(sym.name, NON_RECURSIVE)) {
4065 if (sym != byName &&
4066 (byName.flags() & CLASH) == 0 &&
4067 sym.kind == byName.kind &&
4068 sym.name != names.error &&
4069 (sym.kind != MTH ||
4070 types.hasSameArgs(sym.type, byName.type) ||
4071 types.hasSameArgs(types.erasure(sym.type), types.erasure(byName.type)))) {
4072 if ((sym.flags() & VARARGS) != (byName.flags() & VARARGS)) {
4073 sym.flags_field |= CLASH;
4074 varargsDuplicateError(pos, sym, byName);
4075 return true;
4076 } else if (sym.kind == MTH && !types.hasSameArgs(sym.type, byName.type, false)) {
4077 duplicateErasureError(pos, sym, byName);
4078 sym.flags_field |= CLASH;
4079 return true;
4080 } else if ((sym.flags() & MATCH_BINDING) != 0 &&
4081 (byName.flags() & MATCH_BINDING) != 0 &&
4082 (byName.flags() & MATCH_BINDING_TO_OUTER) == 0) {
4083 if (!sym.type.isErroneous()) {
4084 log.error(pos, Errors.MatchBindingExists);
4085 sym.flags_field |= CLASH;
4086 }
4087 return false;
4088 } else {
4089 duplicateError(pos, byName);
4090 return false;
4091 }
4092 }
4093 }
4094 return true;
4095 }
4096
4097 /** Report duplicate declaration error.
4098 */
4099 void duplicateErasureError(DiagnosticPosition pos, Symbol sym1, Symbol sym2) {
4100 if (!sym1.type.isErroneous() && !sym2.type.isErroneous()) {
4101 log.error(pos, Errors.NameClashSameErasure(sym1, sym2));
4102 }
4103 }
4104
4105 /**Check that types imported through the ordinary imports don't clash with types imported
4106 * by other (static or ordinary) imports. Note that two static imports may import two clashing
4107 * types without an error on the imports.
4108 * @param toplevel The toplevel tree for which the test should be performed.
4109 */
4110 void checkImportsUnique(JCCompilationUnit toplevel) {
4111 WriteableScope ordinallyImportedSoFar = WriteableScope.create(toplevel.packge);
4112 WriteableScope staticallyImportedSoFar = WriteableScope.create(toplevel.packge);
4113 WriteableScope topLevelScope = toplevel.toplevelScope;
4114
4115 for (JCTree def : toplevel.defs) {
4116 if (!def.hasTag(IMPORT))
4117 continue;
4118
4119 JCImport imp = (JCImport) def;
4120
4121 if (imp.importScope == null)
4122 continue;
4123
4124 for (Symbol sym : imp.importScope.getSymbols(sym -> sym.kind == TYP)) {
4125 if (imp.isStatic()) {
4126 checkUniqueImport(imp.pos(), ordinallyImportedSoFar, staticallyImportedSoFar, topLevelScope, sym, true);
4127 staticallyImportedSoFar.enter(sym);
4128 } else {
4129 checkUniqueImport(imp.pos(), ordinallyImportedSoFar, staticallyImportedSoFar, topLevelScope, sym, false);
4130 ordinallyImportedSoFar.enter(sym);
4131 }
4132 }
4133
4134 imp.importScope = null;
4135 }
4136 }
4137
4138 /** Check that single-type import is not already imported or top-level defined,
4139 * but make an exception for two single-type imports which denote the same type.
4140 * @param pos Position for error reporting.
4141 * @param ordinallyImportedSoFar A Scope containing types imported so far through
4142 * ordinary imports.
4143 * @param staticallyImportedSoFar A Scope containing types imported so far through
4144 * static imports.
4145 * @param topLevelScope The current file's top-level Scope
4146 * @param sym The symbol.
4147 * @param staticImport Whether or not this was a static import
4148 */
4149 private boolean checkUniqueImport(DiagnosticPosition pos, Scope ordinallyImportedSoFar,
4150 Scope staticallyImportedSoFar, Scope topLevelScope,
4151 Symbol sym, boolean staticImport) {
4152 Predicate<Symbol> duplicates = candidate -> candidate != sym && !candidate.type.isErroneous();
4153 Symbol ordinaryClashing = ordinallyImportedSoFar.findFirst(sym.name, duplicates);
4154 Symbol staticClashing = null;
4155 if (ordinaryClashing == null && !staticImport) {
4156 staticClashing = staticallyImportedSoFar.findFirst(sym.name, duplicates);
4157 }
4158 if (ordinaryClashing != null || staticClashing != null) {
4159 if (ordinaryClashing != null)
4160 log.error(pos, Errors.AlreadyDefinedSingleImport(ordinaryClashing));
4161 else
4162 log.error(pos, Errors.AlreadyDefinedStaticSingleImport(staticClashing));
4163 return false;
4164 }
4165 Symbol clashing = topLevelScope.findFirst(sym.name, duplicates);
4166 if (clashing != null) {
4167 log.error(pos, Errors.AlreadyDefinedThisUnit(clashing));
4168 return false;
4169 }
4170 return true;
4171 }
4172
4173 /** Check that a qualified name is in canonical form (for import decls).
4174 */
4175 public void checkCanonical(JCTree tree) {
4176 if (!isCanonical(tree))
4177 log.error(tree.pos(),
4178 Errors.ImportRequiresCanonical(TreeInfo.symbol(tree)));
4179 }
4180 // where
4181 private boolean isCanonical(JCTree tree) {
4182 while (tree.hasTag(SELECT)) {
4183 JCFieldAccess s = (JCFieldAccess) tree;
4184 if (s.sym.owner.getQualifiedName() != TreeInfo.symbol(s.selected).getQualifiedName())
4185 return false;
4186 tree = s.selected;
4187 }
4188 return true;
4189 }
4190
4191 /** Check that an auxiliary class is not accessed from any other file than its own.
4192 */
4193 void checkForBadAuxiliaryClassAccess(DiagnosticPosition pos, Env<AttrContext> env, ClassSymbol c) {
4194 if (lint.isEnabled(Lint.LintCategory.AUXILIARYCLASS) &&
4195 (c.flags() & AUXILIARY) != 0 &&
4196 rs.isAccessible(env, c) &&
4197 !fileManager.isSameFile(c.sourcefile, env.toplevel.sourcefile))
4198 {
4199 log.warning(pos,
4200 Warnings.AuxiliaryClassAccessedFromOutsideOfItsSourceFile(c, c.sourcefile));
4201 }
4202 }
4203
4204 /**
4205 * Check for a default constructor in an exported package.
4206 */
4207 void checkDefaultConstructor(ClassSymbol c, DiagnosticPosition pos) {
4208 if (lint.isEnabled(LintCategory.MISSING_EXPLICIT_CTOR) &&
4209 ((c.flags() & (ENUM | RECORD)) == 0) &&
4210 !c.isAnonymous() &&
4211 ((c.flags() & (PUBLIC | PROTECTED)) != 0) &&
4212 Feature.MODULES.allowedInSource(source)) {
4213 NestingKind nestingKind = c.getNestingKind();
4214 switch (nestingKind) {
4215 case ANONYMOUS,
4216 LOCAL -> {return;}
4217 case TOP_LEVEL -> {;} // No additional checks needed
4218 case MEMBER -> {
4219 // For nested member classes, all the enclosing
4220 // classes must be public or protected.
4221 Symbol owner = c.owner;
4222 while (owner != null && owner.kind == TYP) {
4223 if ((owner.flags() & (PUBLIC | PROTECTED)) == 0)
4224 return;
4225 owner = owner.owner;
4226 }
4227 }
4228 }
4229
4230 // Only check classes in named packages exported by its module
4231 PackageSymbol pkg = c.packge();
4232 if (!pkg.isUnnamed()) {
4233 ModuleSymbol modle = pkg.modle;
4234 for (ExportsDirective exportDir : modle.exports) {
4235 // Report warning only if the containing
4236 // package is unconditionally exported
4237 if (exportDir.packge.equals(pkg)) {
4238 if (exportDir.modules == null || exportDir.modules.isEmpty()) {
4239 // Warning may be suppressed by
4240 // annotations; check again for being
4241 // enabled in the deferred context.
4242 deferredLintHandler.report(() -> {
4243 if (lint.isEnabled(LintCategory.MISSING_EXPLICIT_CTOR))
4244 log.warning(LintCategory.MISSING_EXPLICIT_CTOR,
4245 pos, Warnings.MissingExplicitCtor(c, pkg, modle));
4246 });
4247 } else {
4248 return;
4249 }
4250 }
4251 }
4252 }
4253 }
4254 return;
4255 }
4256
4257 private class ConversionWarner extends Warner {
4258 final String uncheckedKey;
4259 final Type found;
4260 final Type expected;
4261 public ConversionWarner(DiagnosticPosition pos, String uncheckedKey, Type found, Type expected) {
4262 super(pos);
4263 this.uncheckedKey = uncheckedKey;
4264 this.found = found;
4265 this.expected = expected;
4266 }
4267
4268 @Override
4269 public void warn(LintCategory lint) {
4270 boolean warned = this.warned;
4271 super.warn(lint);
4272 if (warned) return; // suppress redundant diagnostics
4273 switch (lint) {
4274 case UNCHECKED:
4275 Check.this.warnUnchecked(pos(), Warnings.ProbFoundReq(diags.fragment(uncheckedKey), found, expected));
4276 break;
4277 case VARARGS:
4278 if (method != null &&
4279 method.attribute(syms.trustMeType.tsym) != null &&
4280 isTrustMeAllowedOnMethod(method) &&
4281 !types.isReifiable(method.type.getParameterTypes().last())) {
4282 Check.this.warnUnsafeVararg(pos(), Warnings.VarargsUnsafeUseVarargsParam(method.params.last()));
4283 }
4284 break;
4285 default:
4286 throw new AssertionError("Unexpected lint: " + lint);
4287 }
4288 }
4289 }
4290
4291 public Warner castWarner(DiagnosticPosition pos, Type found, Type expected) {
4292 return new ConversionWarner(pos, "unchecked.cast.to.type", found, expected);
4293 }
4294
4295 public Warner convertWarner(DiagnosticPosition pos, Type found, Type expected) {
4296 return new ConversionWarner(pos, "unchecked.assign", found, expected);
4297 }
4298
4299 public void checkFunctionalInterface(JCClassDecl tree, ClassSymbol cs) {
4300 Compound functionalType = cs.attribute(syms.functionalInterfaceType.tsym);
4301
4302 if (functionalType != null) {
4303 try {
4304 types.findDescriptorSymbol((TypeSymbol)cs);
4305 } catch (Types.FunctionDescriptorLookupError ex) {
4306 DiagnosticPosition pos = tree.pos();
4307 for (JCAnnotation a : tree.getModifiers().annotations) {
4308 if (a.annotationType.type.tsym == syms.functionalInterfaceType.tsym) {
4309 pos = a.pos();
4310 break;
4311 }
4312 }
4313 log.error(pos, Errors.BadFunctionalIntfAnno1(ex.getDiagnostic()));
4314 }
4315 }
4316 }
4317
4318 public void checkImportsResolvable(final JCCompilationUnit toplevel) {
4319 for (final JCImport imp : toplevel.getImports()) {
4320 if (!imp.staticImport || !imp.qualid.hasTag(SELECT))
4321 continue;
4322 final JCFieldAccess select = (JCFieldAccess) imp.qualid;
4323 final Symbol origin;
4324 if (select.name == names.asterisk || (origin = TreeInfo.symbol(select.selected)) == null || origin.kind != TYP)
4325 continue;
4326
4327 TypeSymbol site = (TypeSymbol) TreeInfo.symbol(select.selected);
4328 if (!checkTypeContainsImportableElement(site, site, toplevel.packge, select.name, new HashSet<Symbol>())) {
4329 log.error(imp.pos(),
4330 Errors.CantResolveLocation(KindName.STATIC,
4331 select.name,
4332 null,
4333 null,
4334 Fragments.Location(kindName(site),
4335 site,
4336 null)));
4337 }
4338 }
4339 }
4340
4341 // Check that packages imported are in scope (JLS 7.4.3, 6.3, 6.5.3.1, 6.5.3.2)
4342 public void checkImportedPackagesObservable(final JCCompilationUnit toplevel) {
4343 OUTER: for (JCImport imp : toplevel.getImports()) {
4344 if (!imp.staticImport && TreeInfo.name(imp.qualid) == names.asterisk) {
4345 TypeSymbol tsym = ((JCFieldAccess)imp.qualid).selected.type.tsym;
4346 if (tsym.kind == PCK && tsym.members().isEmpty() &&
4347 !(Feature.IMPORT_ON_DEMAND_OBSERVABLE_PACKAGES.allowedInSource(source) && tsym.exists())) {
4348 log.error(DiagnosticFlag.RESOLVE_ERROR, imp.pos, Errors.DoesntExist(tsym));
4349 }
4350 }
4351 }
4352 }
4353
4354 private boolean checkTypeContainsImportableElement(TypeSymbol tsym, TypeSymbol origin, PackageSymbol packge, Name name, Set<Symbol> processed) {
4355 if (tsym == null || !processed.add(tsym))
4356 return false;
4357
4358 // also search through inherited names
4359 if (checkTypeContainsImportableElement(types.supertype(tsym.type).tsym, origin, packge, name, processed))
4360 return true;
4361
4362 for (Type t : types.interfaces(tsym.type))
4363 if (checkTypeContainsImportableElement(t.tsym, origin, packge, name, processed))
4364 return true;
4365
4366 for (Symbol sym : tsym.members().getSymbolsByName(name)) {
4367 if (sym.isStatic() &&
4368 importAccessible(sym, packge) &&
4369 sym.isMemberOf(origin, types)) {
4370 return true;
4371 }
4372 }
4373
4374 return false;
4375 }
4376
4377 // is the sym accessible everywhere in packge?
4378 public boolean importAccessible(Symbol sym, PackageSymbol packge) {
4379 try {
4380 int flags = (int)(sym.flags() & AccessFlags);
4381 switch (flags) {
4382 default:
4383 case PUBLIC:
4384 return true;
4385 case PRIVATE:
4386 return false;
4387 case 0:
4388 case PROTECTED:
4389 return sym.packge() == packge;
4390 }
4391 } catch (ClassFinder.BadClassFile err) {
4392 throw err;
4393 } catch (CompletionFailure ex) {
4394 return false;
4395 }
4396 }
4397
4398 public void checkLeaksNotAccessible(Env<AttrContext> env, JCClassDecl check) {
4399 JCCompilationUnit toplevel = env.toplevel;
4400
4401 if ( toplevel.modle == syms.unnamedModule
4402 || toplevel.modle == syms.noModule
4403 || (check.sym.flags() & COMPOUND) != 0) {
4404 return ;
4405 }
4406
4407 ExportsDirective currentExport = findExport(toplevel.packge);
4408
4409 if ( currentExport == null //not exported
4410 || currentExport.modules != null) //don't check classes in qualified export
4411 return ;
4412
4413 new TreeScanner() {
4414 Lint lint = env.info.lint;
4415 boolean inSuperType;
4416
4417 @Override
4418 public void visitBlock(JCBlock tree) {
4419 }
4420 @Override
4421 public void visitMethodDef(JCMethodDecl tree) {
4422 if (!isAPISymbol(tree.sym))
4423 return;
4424 Lint prevLint = lint;
4425 try {
4426 lint = lint.augment(tree.sym);
4427 if (lint.isEnabled(LintCategory.EXPORTS)) {
4428 super.visitMethodDef(tree);
4429 }
4430 } finally {
4431 lint = prevLint;
4432 }
4433 }
4434 @Override
4435 public void visitVarDef(JCVariableDecl tree) {
4436 if (!isAPISymbol(tree.sym) && tree.sym.owner.kind != MTH)
4437 return;
4438 Lint prevLint = lint;
4439 try {
4440 lint = lint.augment(tree.sym);
4441 if (lint.isEnabled(LintCategory.EXPORTS)) {
4442 scan(tree.mods);
4443 scan(tree.vartype);
4444 }
4445 } finally {
4446 lint = prevLint;
4447 }
4448 }
4449 @Override
4450 public void visitClassDef(JCClassDecl tree) {
4451 if (tree != check)
4452 return ;
4453
4454 if (!isAPISymbol(tree.sym))
4455 return ;
4456
4457 Lint prevLint = lint;
4458 try {
4459 lint = lint.augment(tree.sym);
4460 if (lint.isEnabled(LintCategory.EXPORTS)) {
4461 scan(tree.mods);
4462 scan(tree.typarams);
4463 try {
4464 inSuperType = true;
4465 scan(tree.extending);
4466 scan(tree.implementing);
4467 } finally {
4468 inSuperType = false;
4469 }
4470 scan(tree.defs);
4471 }
4472 } finally {
4473 lint = prevLint;
4474 }
4475 }
4476 @Override
4477 public void visitTypeApply(JCTypeApply tree) {
4478 scan(tree.clazz);
4479 boolean oldInSuperType = inSuperType;
4480 try {
4481 inSuperType = false;
4482 scan(tree.arguments);
4483 } finally {
4484 inSuperType = oldInSuperType;
4485 }
4486 }
4487 @Override
4488 public void visitIdent(JCIdent tree) {
4489 Symbol sym = TreeInfo.symbol(tree);
4490 if (sym.kind == TYP && !sym.type.hasTag(TYPEVAR)) {
4491 checkVisible(tree.pos(), sym, toplevel.packge, inSuperType);
4492 }
4493 }
4494
4495 @Override
4496 public void visitSelect(JCFieldAccess tree) {
4497 Symbol sym = TreeInfo.symbol(tree);
4498 Symbol sitesym = TreeInfo.symbol(tree.selected);
4499 if (sym.kind == TYP && sitesym.kind == PCK) {
4500 checkVisible(tree.pos(), sym, toplevel.packge, inSuperType);
4501 } else {
4502 super.visitSelect(tree);
4503 }
4504 }
4505
4506 @Override
4507 public void visitAnnotation(JCAnnotation tree) {
4508 if (tree.attribute.type.tsym.getAnnotation(java.lang.annotation.Documented.class) != null)
4509 super.visitAnnotation(tree);
4510 }
4511
4512 }.scan(check);
4513 }
4514 //where:
4515 private ExportsDirective findExport(PackageSymbol pack) {
4516 for (ExportsDirective d : pack.modle.exports) {
4517 if (d.packge == pack)
4518 return d;
4519 }
4520
4521 return null;
4522 }
4523 private boolean isAPISymbol(Symbol sym) {
4524 while (sym.kind != PCK) {
4525 if ((sym.flags() & Flags.PUBLIC) == 0 && (sym.flags() & Flags.PROTECTED) == 0) {
4526 return false;
4527 }
4528 sym = sym.owner;
4529 }
4530 return true;
4531 }
4532 private void checkVisible(DiagnosticPosition pos, Symbol what, PackageSymbol inPackage, boolean inSuperType) {
4533 if (!isAPISymbol(what) && !inSuperType) { //package private/private element
4534 log.warning(LintCategory.EXPORTS, pos, Warnings.LeaksNotAccessible(kindName(what), what, what.packge().modle));
4535 return ;
4536 }
4537
4538 PackageSymbol whatPackage = what.packge();
4539 ExportsDirective whatExport = findExport(whatPackage);
4540 ExportsDirective inExport = findExport(inPackage);
4541
4542 if (whatExport == null) { //package not exported:
4543 log.warning(LintCategory.EXPORTS, pos, Warnings.LeaksNotAccessibleUnexported(kindName(what), what, what.packge().modle));
4544 return ;
4545 }
4546
4547 if (whatExport.modules != null) {
4548 if (inExport.modules == null || !whatExport.modules.containsAll(inExport.modules)) {
4549 log.warning(LintCategory.EXPORTS, pos, Warnings.LeaksNotAccessibleUnexportedQualified(kindName(what), what, what.packge().modle));
4550 }
4551 }
4552
4553 if (whatPackage.modle != inPackage.modle && whatPackage.modle != syms.java_base) {
4554 //check that relativeTo.modle requires transitive what.modle, somehow:
4555 List<ModuleSymbol> todo = List.of(inPackage.modle);
4556
4557 while (todo.nonEmpty()) {
4558 ModuleSymbol current = todo.head;
4559 todo = todo.tail;
4560 if (current == whatPackage.modle)
4561 return ; //OK
4562 if ((current.flags() & Flags.AUTOMATIC_MODULE) != 0)
4563 continue; //for automatic modules, don't look into their dependencies
4564 for (RequiresDirective req : current.requires) {
4565 if (req.isTransitive()) {
4566 todo = todo.prepend(req.module);
4567 }
4568 }
4569 }
4570
4571 log.warning(LintCategory.EXPORTS, pos, Warnings.LeaksNotAccessibleNotRequiredTransitive(kindName(what), what, what.packge().modle));
4572 }
4573 }
4574
4575 void checkModuleExists(final DiagnosticPosition pos, ModuleSymbol msym) {
4576 if (msym.kind != MDL) {
4577 deferredLintHandler.report(() -> {
4578 if (lint.isEnabled(LintCategory.MODULE))
4579 log.warning(LintCategory.MODULE, pos, Warnings.ModuleNotFound(msym));
4580 });
4581 }
4582 }
4583
4584 void checkPackageExistsForOpens(final DiagnosticPosition pos, PackageSymbol packge) {
4585 if (packge.members().isEmpty() &&
4586 ((packge.flags() & Flags.HAS_RESOURCE) == 0)) {
4587 deferredLintHandler.report(() -> {
4588 if (lint.isEnabled(LintCategory.OPENS))
4589 log.warning(pos, Warnings.PackageEmptyOrNotFound(packge));
4590 });
4591 }
4592 }
4593
4594 void checkModuleRequires(final DiagnosticPosition pos, final RequiresDirective rd) {
4595 if ((rd.module.flags() & Flags.AUTOMATIC_MODULE) != 0) {
4596 deferredLintHandler.report(() -> {
4597 if (rd.isTransitive() && lint.isEnabled(LintCategory.REQUIRES_TRANSITIVE_AUTOMATIC)) {
4598 log.warning(pos, Warnings.RequiresTransitiveAutomatic);
4599 } else if (lint.isEnabled(LintCategory.REQUIRES_AUTOMATIC)) {
4600 log.warning(pos, Warnings.RequiresAutomatic);
4601 }
4602 });
4603 }
4604 }
4605
4606 /**
4607 * Verify the case labels conform to the constraints. Checks constraints related
4608 * combinations of patterns and other labels.
4609 *
4610 * @param cases the cases that should be checked.
4611 */
4612 void checkSwitchCaseStructure(List<JCCase> cases) {
4613 for (List<JCCase> l = cases; l.nonEmpty(); l = l.tail) {
4614 JCCase c = l.head;
4615 if (c.labels.head instanceof JCConstantCaseLabel constLabel) {
4616 if (TreeInfo.isNull(constLabel.expr)) {
4617 if (c.labels.tail.nonEmpty()) {
4618 if (c.labels.tail.head instanceof JCDefaultCaseLabel defLabel) {
4619 if (c.labels.tail.tail.nonEmpty()) {
4620 log.error(c.labels.tail.tail.head.pos(), Errors.InvalidCaseLabelCombination);
4621 }
4622 } else {
4623 log.error(c.labels.tail.head.pos(), Errors.InvalidCaseLabelCombination);
4624 }
4625 }
4626 } else {
4627 for (JCCaseLabel label : c.labels.tail) {
4628 if (!(label instanceof JCConstantCaseLabel) || TreeInfo.isNullCaseLabel(label)) {
4629 log.error(label.pos(), Errors.InvalidCaseLabelCombination);
4630 break;
4631 }
4632 }
4633 }
4634 } else {
4635 if (c.labels.tail.nonEmpty()) {
4636 log.error(c.labels.tail.head.pos(), Errors.FlowsThroughFromPattern);
4637 }
4638 }
4639 }
4640
4641 boolean isCaseStatementGroup = cases.nonEmpty() &&
4642 cases.head.caseKind == CaseTree.CaseKind.STATEMENT;
4643
4644 if (isCaseStatementGroup) {
4645 boolean previousCompletessNormally = false;
4646 for (List<JCCase> l = cases; l.nonEmpty(); l = l.tail) {
4647 JCCase c = l.head;
4648 if (previousCompletessNormally &&
4649 c.stats.nonEmpty() &&
4650 c.labels.head instanceof JCPatternCaseLabel patternLabel &&
4651 hasBindings(patternLabel.pat)) {
4652 log.error(c.labels.head.pos(), Errors.FlowsThroughToPattern);
4653 } else if (c.stats.isEmpty() &&
4654 c.labels.head instanceof JCPatternCaseLabel patternLabel &&
4655 hasBindings(patternLabel.pat) &&
4656 hasStatements(l.tail)) {
4657 log.error(c.labels.head.pos(), Errors.FlowsThroughFromPattern);
4658 }
4659 previousCompletessNormally = c.completesNormally;
4660 }
4661 }
4662 }
4663
4664 boolean hasBindings(JCPattern p) {
4665 boolean[] bindings = new boolean[1];
4666
4667 new TreeScanner() {
4668 @Override
4669 public void visitBindingPattern(JCBindingPattern tree) {
4670 bindings[0] = true;
4671 super.visitBindingPattern(tree);
4672 }
4673 }.scan(p);
4674
4675 return bindings[0];
4676 }
4677
4678 boolean hasStatements(List<JCCase> cases) {
4679 for (List<JCCase> l = cases; l.nonEmpty(); l = l.tail) {
4680 if (l.head.stats.nonEmpty()) {
4681 return true;
4682 }
4683 }
4684
4685 return false;
4686 }
4687 void checkSwitchCaseLabelDominated(List<JCCase> cases) {
4688 List<JCCaseLabel> caseLabels = List.nil();
4689 boolean seenDefault = false;
4690 boolean seenDefaultLabel = false;
4691 boolean warnDominatedByDefault = false;
4692 for (List<JCCase> l = cases; l.nonEmpty(); l = l.tail) {
4693 JCCase c = l.head;
4694 for (JCCaseLabel label : c.labels) {
4695 if (label.hasTag(DEFAULTCASELABEL)) {
4696 seenDefault = true;
4697 seenDefaultLabel |=
4698 TreeInfo.isNullCaseLabel(c.labels.head);
4699 continue;
4700 }
4701 if (TreeInfo.isNullCaseLabel(label)) {
4702 if (seenDefault) {
4703 log.error(label.pos(), Errors.PatternDominated);
4704 }
4705 continue;
4706 }
4707 if (seenDefault && !warnDominatedByDefault) {
4708 if (label.hasTag(PATTERNCASELABEL) ||
4709 (label instanceof JCConstantCaseLabel && seenDefaultLabel)) {
4710 log.error(label.pos(), Errors.PatternDominated);
4711 warnDominatedByDefault = true;
4712 }
4713 }
4714 Type currentType = labelType(label);
4715 for (JCCaseLabel testCaseLabel : caseLabels) {
4716 Type testType = labelType(testCaseLabel);
4717 if (types.isSubtype(currentType, testType) &&
4718 !currentType.hasTag(ERROR) && !testType.hasTag(ERROR)) {
4719 //the current label is potentially dominated by the existing (test) label, check:
4720 boolean dominated = false;
4721 if (label instanceof JCConstantCaseLabel) {
4722 dominated |= !(testCaseLabel instanceof JCConstantCaseLabel);
4723 } else if (label instanceof JCPatternCaseLabel patternCL &&
4724 testCaseLabel instanceof JCPatternCaseLabel testPatternCaseLabel &&
4725 TreeInfo.unguardedCaseLabel(testCaseLabel)) {
4726 dominated = patternDominated(testPatternCaseLabel.pat,
4727 patternCL.pat);
4728 }
4729 if (dominated) {
4730 log.error(label.pos(), Errors.PatternDominated);
4731 }
4732 }
4733 }
4734 caseLabels = caseLabels.prepend(label);
4735 }
4736 }
4737 }
4738 //where:
4739 private Type labelType(JCCaseLabel label) {
4740 return types.erasure(switch (label.getTag()) {
4741 case PATTERNCASELABEL -> ((JCPatternCaseLabel) label).pat.type;
4742 case CONSTANTCASELABEL -> types.boxedTypeOrType(((JCConstantCaseLabel) label).expr.type);
4743 default -> throw Assert.error("Unexpected tree kind: " + label.getTag());
4744 });
4745 }
4746 private boolean patternDominated(JCPattern existingPattern, JCPattern currentPattern) {
4747 Type existingPatternType = types.erasure(existingPattern.type);
4748 Type currentPatternType = types.erasure(currentPattern.type);
4749 if (existingPatternType.isPrimitive() ^ currentPatternType.isPrimitive()) {
4750 return false;
4751 }
4752 if (existingPatternType.isPrimitive()) {
4753 return types.isSameType(existingPatternType, currentPatternType);
4754 } else {
4755 if (!types.isSubtype(currentPatternType, existingPatternType)) {
4756 return false;
4757 }
4758 }
4759 while (existingPattern instanceof JCParenthesizedPattern parenthesized) {
4760 existingPattern = parenthesized.pattern;
4761 }
4762 while (currentPattern instanceof JCParenthesizedPattern parenthesized) {
4763 currentPattern = parenthesized.pattern;
4764 }
4765 if (currentPattern instanceof JCBindingPattern) {
4766 return existingPattern instanceof JCBindingPattern;
4767 } else if (currentPattern instanceof JCRecordPattern currentRecordPattern) {
4768 if (existingPattern instanceof JCBindingPattern) {
4769 return true;
4770 } else if (existingPattern instanceof JCRecordPattern existingRecordPattern) {
4771 List<JCPattern> existingNested = existingRecordPattern.nested;
4772 List<JCPattern> currentNested = currentRecordPattern.nested;
4773 if (existingNested.size() != currentNested.size()) {
4774 return false;
4775 }
4776 while (existingNested.nonEmpty()) {
4777 if (!patternDominated(existingNested.head, currentNested.head)) {
4778 return false;
4779 }
4780 existingNested = existingNested.tail;
4781 currentNested = currentNested.tail;
4782 }
4783 return true;
4784 } else {
4785 Assert.error("Unknown pattern: " + existingPattern.getTag());
4786 }
4787 } else {
4788 Assert.error("Unknown pattern: " + currentPattern.getTag());
4789 }
4790 return false;
4791 }
4792
4793 /** check if a type is a subtype of Externalizable, if that is available. */
4794 boolean isExternalizable(Type t) {
4795 try {
4796 syms.externalizableType.complete();
4797 }
4798 catch (CompletionFailure e) {
4799 return false;
4800 }
4801 return types.isSubtype(t, syms.externalizableType);
4802 }
4803
4804 /**
4805 * Check structure of serialization declarations.
4806 */
4807 public void checkSerialStructure(JCClassDecl tree, ClassSymbol c) {
4808 (new SerialTypeVisitor()).visit(c, tree);
4809 }
4810
4811 /**
4812 * This visitor will warn if a serialization-related field or
4813 * method is declared in a suspicious or incorrect way. In
4814 * particular, it will warn for cases where the runtime
4815 * serialization mechanism will silently ignore a mis-declared
4816 * entity.
4817 *
4818 * Distinguished serialization-related fields and methods:
4819 *
4820 * Methods:
4821 *
4822 * private void writeObject(ObjectOutputStream stream) throws IOException
4823 * ANY-ACCESS-MODIFIER Object writeReplace() throws ObjectStreamException
4824 *
4825 * private void readObject(ObjectInputStream stream) throws IOException, ClassNotFoundException
4826 * private void readObjectNoData() throws ObjectStreamException
4827 * ANY-ACCESS-MODIFIER Object readResolve() throws ObjectStreamException
4828 *
4829 * Fields:
4830 *
4831 * private static final long serialVersionUID
4832 * private static final ObjectStreamField[] serialPersistentFields
4833 *
4834 * Externalizable: methods defined on the interface
4835 * public void writeExternal(ObjectOutput) throws IOException
4836 * public void readExternal(ObjectInput) throws IOException
4837 */
4838 private class SerialTypeVisitor extends ElementKindVisitor14<Void, JCClassDecl> {
4839 SerialTypeVisitor() {
4840 this.lint = Check.this.lint;
4841 }
4842
4843 private static final Set<String> serialMethodNames =
4844 Set.of("writeObject", "writeReplace",
4845 "readObject", "readObjectNoData",
4846 "readResolve");
4847
4848 private static final Set<String> serialFieldNames =
4849 Set.of("serialVersionUID", "serialPersistentFields");
4850
4851 // Type of serialPersistentFields
4852 private final Type OSF_TYPE = new Type.ArrayType(syms.objectStreamFieldType, syms.arrayClass);
4853
4854 Lint lint;
4855
4856 @Override
4857 public Void defaultAction(Element e, JCClassDecl p) {
4858 throw new IllegalArgumentException(Objects.requireNonNullElse(e.toString(), ""));
4859 }
4860
4861 @Override
4862 public Void visitType(TypeElement e, JCClassDecl p) {
4863 runUnderLint(e, p, (symbol, param) -> super.visitType(symbol, param));
4864 return null;
4865 }
4866
4867 @Override
4868 public Void visitTypeAsClass(TypeElement e,
4869 JCClassDecl p) {
4870 // Anonymous classes filtered out by caller.
4871
4872 ClassSymbol c = (ClassSymbol)e;
4873
4874 checkCtorAccess(p, c);
4875
4876 // Check for missing serialVersionUID; check *not* done
4877 // for enums or records.
4878 VarSymbol svuidSym = null;
4879 for (Symbol sym : c.members().getSymbolsByName(names.serialVersionUID)) {
4880 if (sym.kind == VAR) {
4881 svuidSym = (VarSymbol)sym;
4882 break;
4883 }
4884 }
4885
4886 if (svuidSym == null) {
4887 log.warning(LintCategory.SERIAL, p.pos(), Warnings.MissingSVUID(c));
4888 }
4889
4890 // Check for serialPersistentFields to gate checks for
4891 // non-serializable non-transient instance fields
4892 boolean serialPersistentFieldsPresent =
4893 c.members()
4894 .getSymbolsByName(names.serialPersistentFields, sym -> sym.kind == VAR)
4895 .iterator()
4896 .hasNext();
4897
4898 // Check declarations of serialization-related methods and
4899 // fields
4900 for(Symbol el : c.getEnclosedElements()) {
4901 runUnderLint(el, p, (enclosed, tree) -> {
4902 String name = null;
4903 switch(enclosed.getKind()) {
4904 case FIELD -> {
4905 if (!serialPersistentFieldsPresent) {
4906 var flags = enclosed.flags();
4907 if ( ((flags & TRANSIENT) == 0) &&
4908 ((flags & STATIC) == 0)) {
4909 Type varType = enclosed.asType();
4910 if (!canBeSerialized(varType)) {
4911 // Note per JLS arrays are
4912 // serializable even if the
4913 // component type is not.
4914 log.warning(LintCategory.SERIAL,
4915 TreeInfo.diagnosticPositionFor(enclosed, tree),
4916 Warnings.NonSerializableInstanceField);
4917 } else if (varType.hasTag(ARRAY)) {
4918 ArrayType arrayType = (ArrayType)varType;
4919 Type elementType = arrayType.elemtype;
4920 while (elementType.hasTag(ARRAY)) {
4921 arrayType = (ArrayType)elementType;
4922 elementType = arrayType.elemtype;
4923 }
4924 if (!canBeSerialized(elementType)) {
4925 log.warning(LintCategory.SERIAL,
4926 TreeInfo.diagnosticPositionFor(enclosed, tree),
4927 Warnings.NonSerializableInstanceFieldArray(elementType));
4928 }
4929 }
4930 }
4931 }
4932
4933 name = enclosed.getSimpleName().toString();
4934 if (serialFieldNames.contains(name)) {
4935 VarSymbol field = (VarSymbol)enclosed;
4936 switch (name) {
4937 case "serialVersionUID" -> checkSerialVersionUID(tree, e, field);
4938 case "serialPersistentFields" -> checkSerialPersistentFields(tree, e, field);
4939 default -> throw new AssertionError();
4940 }
4941 }
4942 }
4943
4944 // Correctly checking the serialization-related
4945 // methods is subtle. For the methods declared to be
4946 // private or directly declared in the class, the
4947 // enclosed elements of the class can be checked in
4948 // turn. However, writeReplace and readResolve can be
4949 // declared in a superclass and inherited. Note that
4950 // the runtime lookup walks the superclass chain
4951 // looking for writeReplace/readResolve via
4952 // Class.getDeclaredMethod. This differs from calling
4953 // Elements.getAllMembers(TypeElement) as the latter
4954 // will also pull in default methods from
4955 // superinterfaces. In other words, the runtime checks
4956 // (which long predate default methods on interfaces)
4957 // do not admit the possibility of inheriting methods
4958 // this way, a difference from general inheritance.
4959
4960 // The current implementation just checks the enclosed
4961 // elements and does not directly check the inherited
4962 // methods. If all the types are being checked this is
4963 // less of a concern; however, there are cases that
4964 // could be missed. In particular, readResolve and
4965 // writeReplace could, in principle, by inherited from
4966 // a non-serializable superclass and thus not checked
4967 // even if compiled with a serializable child class.
4968 case METHOD -> {
4969 var method = (MethodSymbol)enclosed;
4970 name = method.getSimpleName().toString();
4971 if (serialMethodNames.contains(name)) {
4972 switch (name) {
4973 case "writeObject" -> checkWriteObject(tree, e, method);
4974 case "writeReplace" -> checkWriteReplace(tree,e, method);
4975 case "readObject" -> checkReadObject(tree,e, method);
4976 case "readObjectNoData" -> checkReadObjectNoData(tree, e, method);
4977 case "readResolve" -> checkReadResolve(tree, e, method);
4978 default -> throw new AssertionError();
4979 }
4980 }
4981 }
4982 }
4983 });
4984 }
4985
4986 return null;
4987 }
4988
4989 boolean canBeSerialized(Type type) {
4990 return type.isPrimitive() || rs.isSerializable(type);
4991 }
4992
4993 /**
4994 * Check that Externalizable class needs a public no-arg
4995 * constructor.
4996 *
4997 * Check that a Serializable class has access to the no-arg
4998 * constructor of its first nonserializable superclass.
4999 */
5000 private void checkCtorAccess(JCClassDecl tree, ClassSymbol c) {
5001 if (isExternalizable(c.type)) {
5002 for(var sym : c.getEnclosedElements()) {
5003 if (sym.isInitOrVNew() &&
5004 ((sym.flags() & PUBLIC) == PUBLIC)) {
5005 if (((MethodSymbol)sym).getParameters().isEmpty()) {
5006 return;
5007 }
5008 }
5009 }
5010 log.warning(LintCategory.SERIAL, tree.pos(),
5011 Warnings.ExternalizableMissingPublicNoArgCtor);
5012 } else {
5013 // Approximate access to the no-arg constructor up in
5014 // the superclass chain by checking that the
5015 // constructor is not private. This may not handle
5016 // some cross-package situations correctly.
5017 Type superClass = c.getSuperclass();
5018 // java.lang.Object is *not* Serializable so this loop
5019 // should terminate.
5020 while (rs.isSerializable(superClass) ) {
5021 try {
5022 superClass = (Type)((TypeElement)(((DeclaredType)superClass)).asElement()).getSuperclass();
5023 } catch(ClassCastException cce) {
5024 return ; // Don't try to recover
5025 }
5026 }
5027 // Non-Serializable superclass
5028 try {
5029 ClassSymbol supertype = ((ClassSymbol)(((DeclaredType)superClass).asElement()));
5030 for(var sym : supertype.getEnclosedElements()) {
5031 if (sym.isInitOrVNew()) {
5032 MethodSymbol ctor = (MethodSymbol)sym;
5033 if (ctor.getParameters().isEmpty()) {
5034 if (((ctor.flags() & PRIVATE) == PRIVATE) ||
5035 // Handle nested classes and implicit this$0
5036 (supertype.getNestingKind() == NestingKind.MEMBER &&
5037 ((supertype.flags() & STATIC) == 0)))
5038 log.warning(LintCategory.SERIAL, tree.pos(),
5039 Warnings.SerializableMissingAccessNoArgCtor(supertype.getQualifiedName()));
5040 }
5041 }
5042 }
5043 } catch (ClassCastException cce) {
5044 return ; // Don't try to recover
5045 }
5046 return;
5047 }
5048 }
5049
5050 private void checkSerialVersionUID(JCClassDecl tree, Element e, VarSymbol svuid) {
5051 // To be effective, serialVersionUID must be marked static
5052 // and final, but private is recommended. But alas, in
5053 // practice there are many non-private serialVersionUID
5054 // fields.
5055 if ((svuid.flags() & (STATIC | FINAL)) !=
5056 (STATIC | FINAL)) {
5057 log.warning(LintCategory.SERIAL,
5058 TreeInfo.diagnosticPositionFor(svuid, tree),
5059 Warnings.ImproperSVUID((Symbol)e));
5060 }
5061
5062 // check svuid has type long
5063 if (!svuid.type.hasTag(LONG)) {
5064 log.warning(LintCategory.SERIAL,
5065 TreeInfo.diagnosticPositionFor(svuid, tree),
5066 Warnings.LongSVUID((Symbol)e));
5067 }
5068
5069 if (svuid.getConstValue() == null)
5070 log.warning(LintCategory.SERIAL,
5071 TreeInfo.diagnosticPositionFor(svuid, tree),
5072 Warnings.ConstantSVUID((Symbol)e));
5073 }
5074
5075 private void checkSerialPersistentFields(JCClassDecl tree, Element e, VarSymbol spf) {
5076 // To be effective, serialPersisentFields must be private, static, and final.
5077 if ((spf.flags() & (PRIVATE | STATIC | FINAL)) !=
5078 (PRIVATE | STATIC | FINAL)) {
5079 log.warning(LintCategory.SERIAL,
5080 TreeInfo.diagnosticPositionFor(spf, tree), Warnings.ImproperSPF);
5081 }
5082
5083 if (!types.isSameType(spf.type, OSF_TYPE)) {
5084 log.warning(LintCategory.SERIAL,
5085 TreeInfo.diagnosticPositionFor(spf, tree), Warnings.OSFArraySPF);
5086 }
5087
5088 if (isExternalizable((Type)(e.asType()))) {
5089 log.warning(LintCategory.SERIAL, tree.pos(),
5090 Warnings.IneffectualSerialFieldExternalizable);
5091 }
5092
5093 // Warn if serialPersistentFields is initialized to a
5094 // literal null.
5095 JCTree spfDecl = TreeInfo.declarationFor(spf, tree);
5096 if (spfDecl != null && spfDecl.getTag() == VARDEF) {
5097 JCVariableDecl variableDef = (JCVariableDecl) spfDecl;
5098 JCExpression initExpr = variableDef.init;
5099 if (initExpr != null && TreeInfo.isNull(initExpr)) {
5100 log.warning(LintCategory.SERIAL, initExpr.pos(),
5101 Warnings.SPFNullInit);
5102 }
5103 }
5104 }
5105
5106 private void checkWriteObject(JCClassDecl tree, Element e, MethodSymbol method) {
5107 // The "synchronized" modifier is seen in the wild on
5108 // readObject and writeObject methods and is generally
5109 // innocuous.
5110
5111 // private void writeObject(ObjectOutputStream stream) throws IOException
5112 checkPrivateNonStaticMethod(tree, method);
5113 checkReturnType(tree, e, method, syms.voidType);
5114 checkOneArg(tree, e, method, syms.objectOutputStreamType);
5115 checkExceptions(tree, e, method, syms.ioExceptionType);
5116 checkExternalizable(tree, e, method);
5117 }
5118
5119 private void checkWriteReplace(JCClassDecl tree, Element e, MethodSymbol method) {
5120 // ANY-ACCESS-MODIFIER Object writeReplace() throws
5121 // ObjectStreamException
5122
5123 // Excluding abstract, could have a more complicated
5124 // rule based on abstract-ness of the class
5125 checkConcreteInstanceMethod(tree, e, method);
5126 checkReturnType(tree, e, method, syms.objectType);
5127 checkNoArgs(tree, e, method);
5128 checkExceptions(tree, e, method, syms.objectStreamExceptionType);
5129 }
5130
5131 private void checkReadObject(JCClassDecl tree, Element e, MethodSymbol method) {
5132 // The "synchronized" modifier is seen in the wild on
5133 // readObject and writeObject methods and is generally
5134 // innocuous.
5135
5136 // private void readObject(ObjectInputStream stream)
5137 // throws IOException, ClassNotFoundException
5138 checkPrivateNonStaticMethod(tree, method);
5139 checkReturnType(tree, e, method, syms.voidType);
5140 checkOneArg(tree, e, method, syms.objectInputStreamType);
5141 checkExceptions(tree, e, method, syms.ioExceptionType, syms.classNotFoundExceptionType);
5142 checkExternalizable(tree, e, method);
5143 }
5144
5145 private void checkReadObjectNoData(JCClassDecl tree, Element e, MethodSymbol method) {
5146 // private void readObjectNoData() throws ObjectStreamException
5147 checkPrivateNonStaticMethod(tree, method);
5148 checkReturnType(tree, e, method, syms.voidType);
5149 checkNoArgs(tree, e, method);
5150 checkExceptions(tree, e, method, syms.objectStreamExceptionType);
5151 checkExternalizable(tree, e, method);
5152 }
5153
5154 private void checkReadResolve(JCClassDecl tree, Element e, MethodSymbol method) {
5155 // ANY-ACCESS-MODIFIER Object readResolve()
5156 // throws ObjectStreamException
5157
5158 // Excluding abstract, could have a more complicated
5159 // rule based on abstract-ness of the class
5160 checkConcreteInstanceMethod(tree, e, method);
5161 checkReturnType(tree,e, method, syms.objectType);
5162 checkNoArgs(tree, e, method);
5163 checkExceptions(tree, e, method, syms.objectStreamExceptionType);
5164 }
5165
5166 void checkPrivateNonStaticMethod(JCClassDecl tree, MethodSymbol method) {
5167 var flags = method.flags();
5168 if ((flags & PRIVATE) == 0) {
5169 log.warning(LintCategory.SERIAL,
5170 TreeInfo.diagnosticPositionFor(method, tree),
5171 Warnings.SerialMethodNotPrivate(method.getSimpleName()));
5172 }
5173
5174 if ((flags & STATIC) != 0) {
5175 log.warning(LintCategory.SERIAL,
5176 TreeInfo.diagnosticPositionFor(method, tree),
5177 Warnings.SerialMethodStatic(method.getSimpleName()));
5178 }
5179 }
5180
5181 /**
5182 * Per section 1.12 "Serialization of Enum Constants" of
5183 * the serialization specification, due to the special
5184 * serialization handling of enums, any writeObject,
5185 * readObject, writeReplace, and readResolve methods are
5186 * ignored as are serialPersistentFields and
5187 * serialVersionUID fields.
5188 */
5189 @Override
5190 public Void visitTypeAsEnum(TypeElement e,
5191 JCClassDecl p) {
5192 for(Element el : e.getEnclosedElements()) {
5193 runUnderLint(el, p, (enclosed, tree) -> {
5194 String name = enclosed.getSimpleName().toString();
5195 switch(enclosed.getKind()) {
5196 case FIELD -> {
5197 if (serialFieldNames.contains(name)) {
5198 log.warning(LintCategory.SERIAL, tree.pos(),
5199 Warnings.IneffectualSerialFieldEnum(name));
5200 }
5201 }
5202
5203 case METHOD -> {
5204 if (serialMethodNames.contains(name)) {
5205 log.warning(LintCategory.SERIAL, tree.pos(),
5206 Warnings.IneffectualSerialMethodEnum(name));
5207 }
5208 }
5209 }
5210 });
5211 }
5212 return null;
5213 }
5214
5215 /**
5216 * Most serialization-related fields and methods on interfaces
5217 * are ineffectual or problematic.
5218 */
5219 @Override
5220 public Void visitTypeAsInterface(TypeElement e,
5221 JCClassDecl p) {
5222 for(Element el : e.getEnclosedElements()) {
5223 runUnderLint(el, p, (enclosed, tree) -> {
5224 String name = null;
5225 switch(enclosed.getKind()) {
5226 case FIELD -> {
5227 var field = (VarSymbol)enclosed;
5228 name = field.getSimpleName().toString();
5229 switch(name) {
5230 case "serialPersistentFields" -> {
5231 log.warning(LintCategory.SERIAL,
5232 TreeInfo.diagnosticPositionFor(field, tree),
5233 Warnings.IneffectualSerialFieldInterface);
5234 }
5235
5236 case "serialVersionUID" -> {
5237 checkSerialVersionUID(tree, e, field);
5238 }
5239 }
5240 }
5241
5242 case METHOD -> {
5243 var method = (MethodSymbol)enclosed;
5244 name = enclosed.getSimpleName().toString();
5245 if (serialMethodNames.contains(name)) {
5246 switch (name) {
5247 case
5248 "readObject",
5249 "readObjectNoData",
5250 "writeObject" -> checkPrivateMethod(tree, e, method);
5251
5252 case
5253 "writeReplace",
5254 "readResolve" -> checkDefaultIneffective(tree, e, method);
5255
5256 default -> throw new AssertionError();
5257 }
5258
5259 }
5260 }
5261 }
5262 });
5263 }
5264
5265 return null;
5266 }
5267
5268 private void checkPrivateMethod(JCClassDecl tree,
5269 Element e,
5270 MethodSymbol method) {
5271 if ((method.flags() & PRIVATE) == 0) {
5272 log.warning(LintCategory.SERIAL,
5273 TreeInfo.diagnosticPositionFor(method, tree),
5274 Warnings.NonPrivateMethodWeakerAccess);
5275 }
5276 }
5277
5278 private void checkDefaultIneffective(JCClassDecl tree,
5279 Element e,
5280 MethodSymbol method) {
5281 if ((method.flags() & DEFAULT) == DEFAULT) {
5282 log.warning(LintCategory.SERIAL,
5283 TreeInfo.diagnosticPositionFor(method, tree),
5284 Warnings.DefaultIneffective);
5285
5286 }
5287 }
5288
5289 @Override
5290 public Void visitTypeAsAnnotationType(TypeElement e,
5291 JCClassDecl p) {
5292 // Per the JLS, annotation types are not serializeable
5293 return null;
5294 }
5295
5296 /**
5297 * From the Java Object Serialization Specification, 1.13
5298 * Serialization of Records:
5299 *
5300 * "The process by which record objects are serialized or
5301 * externalized cannot be customized; any class-specific
5302 * writeObject, readObject, readObjectNoData, writeExternal,
5303 * and readExternal methods defined by record classes are
5304 * ignored during serialization and deserialization. However,
5305 * a substitute object to be serialized or a designate
5306 * replacement may be specified, by the writeReplace and
5307 * readResolve methods, respectively. Any
5308 * serialPersistentFields field declaration is
5309 * ignored. Documenting serializable fields and data for
5310 * record classes is unnecessary, since there is no variation
5311 * in the serial form, other than whether a substitute or
5312 * replacement object is used. The serialVersionUID of a
5313 * record class is 0L unless explicitly declared. The
5314 * requirement for matching serialVersionUID values is waived
5315 * for record classes."
5316 */
5317 @Override
5318 public Void visitTypeAsRecord(TypeElement e,
5319 JCClassDecl p) {
5320 for(Element el : e.getEnclosedElements()) {
5321 runUnderLint(el, p, (enclosed, tree) -> {
5322 String name = enclosed.getSimpleName().toString();
5323 switch(enclosed.getKind()) {
5324 case FIELD -> {
5325 switch(name) {
5326 case "serialPersistentFields" -> {
5327 log.warning(LintCategory.SERIAL, tree.pos(),
5328 Warnings.IneffectualSerialFieldRecord);
5329 }
5330
5331 case "serialVersionUID" -> {
5332 // Could generate additional warning that
5333 // svuid value is not checked to match for
5334 // records.
5335 checkSerialVersionUID(tree, e, (VarSymbol)enclosed);
5336 }
5337
5338 }
5339 }
5340
5341 case METHOD -> {
5342 var method = (MethodSymbol)enclosed;
5343 switch(name) {
5344 case "writeReplace" -> checkWriteReplace(tree, e, method);
5345 case "readResolve" -> checkReadResolve(tree, e, method);
5346 default -> {
5347 if (serialMethodNames.contains(name)) {
5348 log.warning(LintCategory.SERIAL, tree.pos(),
5349 Warnings.IneffectualSerialMethodRecord(name));
5350 }
5351 }
5352 }
5353
5354 }
5355 }
5356 });
5357 }
5358 return null;
5359 }
5360
5361 void checkConcreteInstanceMethod(JCClassDecl tree,
5362 Element enclosing,
5363 MethodSymbol method) {
5364 if ((method.flags() & (STATIC | ABSTRACT)) != 0) {
5365 log.warning(LintCategory.SERIAL,
5366 TreeInfo.diagnosticPositionFor(method, tree),
5367 Warnings.SerialConcreteInstanceMethod(method.getSimpleName()));
5368 }
5369 }
5370
5371 private void checkReturnType(JCClassDecl tree,
5372 Element enclosing,
5373 MethodSymbol method,
5374 Type expectedReturnType) {
5375 // Note: there may be complications checking writeReplace
5376 // and readResolve since they return Object and could, in
5377 // principle, have covariant overrides and any synthetic
5378 // bridge method would not be represented here for
5379 // checking.
5380 Type rtype = method.getReturnType();
5381 if (!types.isSameType(expectedReturnType, rtype)) {
5382 log.warning(LintCategory.SERIAL,
5383 TreeInfo.diagnosticPositionFor(method, tree),
5384 Warnings.SerialMethodUnexpectedReturnType(method.getSimpleName(),
5385 rtype, expectedReturnType));
5386 }
5387 }
5388
5389 private void checkOneArg(JCClassDecl tree,
5390 Element enclosing,
5391 MethodSymbol method,
5392 Type expectedType) {
5393 String name = method.getSimpleName().toString();
5394
5395 var parameters= method.getParameters();
5396
5397 if (parameters.size() != 1) {
5398 log.warning(LintCategory.SERIAL,
5399 TreeInfo.diagnosticPositionFor(method, tree),
5400 Warnings.SerialMethodOneArg(method.getSimpleName(), parameters.size()));
5401 return;
5402 }
5403
5404 Type parameterType = parameters.get(0).asType();
5405 if (!types.isSameType(parameterType, expectedType)) {
5406 log.warning(LintCategory.SERIAL,
5407 TreeInfo.diagnosticPositionFor(method, tree),
5408 Warnings.SerialMethodParameterType(method.getSimpleName(),
5409 expectedType,
5410 parameterType));
5411 }
5412 }
5413
5414 private void checkNoArgs(JCClassDecl tree, Element enclosing, MethodSymbol method) {
5415 var parameters = method.getParameters();
5416 if (!parameters.isEmpty()) {
5417 log.warning(LintCategory.SERIAL,
5418 TreeInfo.diagnosticPositionFor(parameters.get(0), tree),
5419 Warnings.SerialMethodNoArgs(method.getSimpleName()));
5420 }
5421 }
5422
5423 private void checkExternalizable(JCClassDecl tree, Element enclosing, MethodSymbol method) {
5424 // If the enclosing class is externalizable, warn for the method
5425 if (isExternalizable((Type)enclosing.asType())) {
5426 log.warning(LintCategory.SERIAL, tree.pos(),
5427 Warnings.IneffectualSerialMethodExternalizable(method.getSimpleName()));
5428 }
5429 return;
5430 }
5431
5432 private void checkExceptions(JCClassDecl tree,
5433 Element enclosing,
5434 MethodSymbol method,
5435 Type... declaredExceptions) {
5436 for (Type thrownType: method.getThrownTypes()) {
5437 // For each exception in the throws clause of the
5438 // method, if not an Error and not a RuntimeException,
5439 // check if the exception is a subtype of a declared
5440 // exception from the throws clause of the
5441 // serialization method in question.
5442 if (types.isSubtype(thrownType, syms.runtimeExceptionType) ||
5443 types.isSubtype(thrownType, syms.errorType) ) {
5444 continue;
5445 } else {
5446 boolean declared = false;
5447 for (Type declaredException : declaredExceptions) {
5448 if (types.isSubtype(thrownType, declaredException)) {
5449 declared = true;
5450 continue;
5451 }
5452 }
5453 if (!declared) {
5454 log.warning(LintCategory.SERIAL,
5455 TreeInfo.diagnosticPositionFor(method, tree),
5456 Warnings.SerialMethodUnexpectedException(method.getSimpleName(),
5457 thrownType));
5458 }
5459 }
5460 }
5461 return;
5462 }
5463
5464 private <E extends Element> Void runUnderLint(E symbol, JCClassDecl p, BiConsumer<E, JCClassDecl> task) {
5465 Lint prevLint = lint;
5466 try {
5467 lint = lint.augment((Symbol) symbol);
5468
5469 if (lint.isEnabled(LintCategory.SERIAL)) {
5470 task.accept(symbol, p);
5471 }
5472
5473 return null;
5474 } finally {
5475 lint = prevLint;
5476 }
5477 }
5478
5479 }
5480
5481 }