1 /*
2 * Copyright (c) 1999, 2023, Oracle and/or its affiliates. All rights reserved.
3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
4 *
5 * This code is free software; you can redistribute it and/or modify it
6 * under the terms of the GNU General Public License version 2 only, as
7 * published by the Free Software Foundation. Oracle designates this
8 * particular file as subject to the "Classpath" exception as provided
9 * by Oracle in the LICENSE file that accompanied this code.
10 *
11 * This code is distributed in the hope that it will be useful, but WITHOUT
12 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
13 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
14 * version 2 for more details (a copy is included in the LICENSE file that
15 * accompanied this code).
16 *
17 * You should have received a copy of the GNU General Public License version
18 * 2 along with this work; if not, write to the Free Software Foundation,
19 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
20 *
21 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
22 * or visit www.oracle.com if you need additional information or have any
23 * questions.
24 */
25
26 package com.sun.tools.javac.comp;
27
28 import java.util.*;
29 import java.util.function.BiConsumer;
30 import java.util.function.BiPredicate;
31 import java.util.function.Predicate;
32 import java.util.function.Supplier;
33 import java.util.function.ToIntBiFunction;
34 import java.util.stream.Collectors;
35 import java.util.stream.StreamSupport;
36
37 import javax.lang.model.element.ElementKind;
38 import javax.lang.model.element.NestingKind;
39 import javax.tools.JavaFileManager;
40
41 import com.sun.source.tree.CaseTree;
42 import com.sun.tools.javac.code.*;
43 import com.sun.tools.javac.code.Attribute.Compound;
44 import com.sun.tools.javac.code.Directive.ExportsDirective;
45 import com.sun.tools.javac.code.Directive.RequiresDirective;
46 import com.sun.tools.javac.code.Source.Feature;
47 import com.sun.tools.javac.comp.Annotate.AnnotationTypeMetadata;
48 import com.sun.tools.javac.jvm.*;
49 import com.sun.tools.javac.resources.CompilerProperties.Errors;
50 import com.sun.tools.javac.resources.CompilerProperties.Fragments;
51 import com.sun.tools.javac.resources.CompilerProperties.Warnings;
52 import com.sun.tools.javac.tree.*;
53 import com.sun.tools.javac.util.*;
54 import com.sun.tools.javac.util.JCDiagnostic.DiagnosticFlag;
55 import com.sun.tools.javac.util.JCDiagnostic.DiagnosticPosition;
56 import com.sun.tools.javac.util.JCDiagnostic.Error;
57 import com.sun.tools.javac.util.JCDiagnostic.Fragment;
58 import com.sun.tools.javac.util.JCDiagnostic.Warning;
59 import com.sun.tools.javac.util.List;
60
61 import com.sun.tools.javac.code.Lint;
62 import com.sun.tools.javac.code.Lint.LintCategory;
63 import com.sun.tools.javac.code.Scope.WriteableScope;
64 import com.sun.tools.javac.code.Type.*;
65 import com.sun.tools.javac.code.Symbol.*;
66 import com.sun.tools.javac.comp.DeferredAttr.DeferredAttrContext;
67 import com.sun.tools.javac.tree.JCTree.*;
68
69 import static com.sun.tools.javac.code.Flags.*;
70 import static com.sun.tools.javac.code.Flags.ANNOTATION;
71 import static com.sun.tools.javac.code.Flags.SYNCHRONIZED;
72 import static com.sun.tools.javac.code.Kinds.*;
73 import static com.sun.tools.javac.code.Kinds.Kind.*;
74 import static com.sun.tools.javac.code.Scope.LookupKind.NON_RECURSIVE;
75 import static com.sun.tools.javac.code.Scope.LookupKind.RECURSIVE;
76 import static com.sun.tools.javac.code.TypeTag.*;
77 import static com.sun.tools.javac.code.TypeTag.WILDCARD;
78
79 import static com.sun.tools.javac.tree.JCTree.Tag.*;
80 import javax.lang.model.element.Element;
81 import javax.lang.model.element.TypeElement;
82 import javax.lang.model.type.DeclaredType;
83 import javax.lang.model.util.ElementKindVisitor14;
84
85 /** Type checking helper class for the attribution phase.
86 *
87 * <p><b>This is NOT part of any supported API.
88 * If you write code that depends on this, you do so at your own risk.
89 * This code and its internal interfaces are subject to change or
90 * deletion without notice.</b>
91 */
92 public class Check {
93 protected static final Context.Key<Check> checkKey = new Context.Key<>();
94
95 // Flag bits indicating which item(s) chosen from a pair of items
96 private static final int FIRST = 0x01;
97 private static final int SECOND = 0x02;
98
99 private final Names names;
100 private final Log log;
101 private final Resolve rs;
102 private final Symtab syms;
103 private final Enter enter;
104 private final DeferredAttr deferredAttr;
105 private final Infer infer;
106 private final Types types;
107 private final TypeAnnotations typeAnnotations;
108 private final JCDiagnostic.Factory diags;
109 private final JavaFileManager fileManager;
110 private final Source source;
111 private final Target target;
112 private final Profile profile;
113 private final Preview preview;
114 private final boolean warnOnAnyAccessToMembers;
115
116 public boolean disablePreviewCheck;
117
118 // The set of lint options currently in effect. It is initialized
119 // from the context, and then is set/reset as needed by Attr as it
120 // visits all the various parts of the trees during attribution.
121 private Lint lint;
122
123 // The method being analyzed in Attr - it is set/reset as needed by
124 // Attr as it visits new method declarations.
125 private MethodSymbol method;
126
127 public static Check instance(Context context) {
128 Check instance = context.get(checkKey);
129 if (instance == null)
130 instance = new Check(context);
131 return instance;
132 }
133
134 @SuppressWarnings("this-escape")
135 protected Check(Context context) {
136 context.put(checkKey, this);
137
138 names = Names.instance(context);
139 log = Log.instance(context);
140 rs = Resolve.instance(context);
141 syms = Symtab.instance(context);
142 enter = Enter.instance(context);
143 deferredAttr = DeferredAttr.instance(context);
144 infer = Infer.instance(context);
145 types = Types.instance(context);
146 typeAnnotations = TypeAnnotations.instance(context);
147 diags = JCDiagnostic.Factory.instance(context);
148 Options options = Options.instance(context);
149 lint = Lint.instance(context);
150 fileManager = context.get(JavaFileManager.class);
151
152 source = Source.instance(context);
153 target = Target.instance(context);
154 warnOnAnyAccessToMembers = options.isSet("warnOnAccessToMembers");
155
156 disablePreviewCheck = false;
157
158 Target target = Target.instance(context);
159 syntheticNameChar = target.syntheticNameChar();
160
161 profile = Profile.instance(context);
162 preview = Preview.instance(context);
163
164 boolean verboseDeprecated = lint.isEnabled(LintCategory.DEPRECATION);
165 boolean verboseRemoval = lint.isEnabled(LintCategory.REMOVAL);
166 boolean verboseUnchecked = lint.isEnabled(LintCategory.UNCHECKED);
167 boolean enforceMandatoryWarnings = true;
168
169 deprecationHandler = new MandatoryWarningHandler(log, null, verboseDeprecated,
170 enforceMandatoryWarnings, "deprecated", LintCategory.DEPRECATION);
171 removalHandler = new MandatoryWarningHandler(log, null, verboseRemoval,
172 enforceMandatoryWarnings, "removal", LintCategory.REMOVAL);
173 uncheckedHandler = new MandatoryWarningHandler(log, null, verboseUnchecked,
174 enforceMandatoryWarnings, "unchecked", LintCategory.UNCHECKED);
175 sunApiHandler = new MandatoryWarningHandler(log, null, false,
176 enforceMandatoryWarnings, "sunapi", null);
177
178 deferredLintHandler = DeferredLintHandler.instance(context);
179
180 allowModules = Feature.MODULES.allowedInSource(source);
181 allowRecords = Feature.RECORDS.allowedInSource(source);
182 allowSealed = Feature.SEALED_CLASSES.allowedInSource(source);
183 allowValueClasses = (!preview.isPreview(Feature.VALUE_CLASSES) || preview.isEnabled()) &&
184 Feature.VALUE_CLASSES.allowedInSource(source);
185 }
186
187 /** Character for synthetic names
188 */
189 char syntheticNameChar;
190
191 /** A table mapping flat names of all compiled classes for each module in this run
192 * to their symbols; maintained from outside.
193 */
194 private Map<Pair<ModuleSymbol, Name>,ClassSymbol> compiled = new HashMap<>();
195
196 /** A handler for messages about deprecated usage.
197 */
198 private MandatoryWarningHandler deprecationHandler;
199
200 /** A handler for messages about deprecated-for-removal usage.
201 */
202 private MandatoryWarningHandler removalHandler;
203
204 /** A handler for messages about unchecked or unsafe usage.
205 */
206 private MandatoryWarningHandler uncheckedHandler;
207
208 /** A handler for messages about using proprietary API.
209 */
210 private MandatoryWarningHandler sunApiHandler;
211
212 /** A handler for deferred lint warnings.
213 */
214 private DeferredLintHandler deferredLintHandler;
215
216 /** Are modules allowed
217 */
218 private final boolean allowModules;
219
220 /** Are records allowed
221 */
222 private final boolean allowRecords;
223
224 /** Are sealed classes allowed
225 */
226 private final boolean allowSealed;
227
228 /** Are value classes allowed
229 */
230 private final boolean allowValueClasses;
231
232 /* *************************************************************************
233 * Errors and Warnings
234 **************************************************************************/
235
236 Lint setLint(Lint newLint) {
237 Lint prev = lint;
238 lint = newLint;
239 return prev;
240 }
241
242 MethodSymbol setMethod(MethodSymbol newMethod) {
243 MethodSymbol prev = method;
244 method = newMethod;
245 return prev;
246 }
247
248 /** Warn about deprecated symbol.
249 * @param pos Position to be used for error reporting.
250 * @param sym The deprecated symbol.
251 */
252 void warnDeprecated(DiagnosticPosition pos, Symbol sym) {
253 if (sym.isDeprecatedForRemoval()) {
254 if (!lint.isSuppressed(LintCategory.REMOVAL)) {
255 if (sym.kind == MDL) {
256 removalHandler.report(pos, Warnings.HasBeenDeprecatedForRemovalModule(sym));
257 } else {
258 removalHandler.report(pos, Warnings.HasBeenDeprecatedForRemoval(sym, sym.location()));
259 }
260 }
261 } else if (!lint.isSuppressed(LintCategory.DEPRECATION)) {
262 if (sym.kind == MDL) {
263 deprecationHandler.report(pos, Warnings.HasBeenDeprecatedModule(sym));
264 } else {
265 deprecationHandler.report(pos, Warnings.HasBeenDeprecated(sym, sym.location()));
266 }
267 }
268 }
269
270 /** Log a preview warning.
271 * @param pos Position to be used for error reporting.
272 * @param msg A Warning describing the problem.
273 */
274 public void warnPreviewAPI(DiagnosticPosition pos, Warning warnKey) {
275 if (!lint.isSuppressed(LintCategory.PREVIEW))
276 preview.reportPreviewWarning(pos, warnKey);
277 }
278
279 /** Log a preview warning.
280 * @param pos Position to be used for error reporting.
281 * @param msg A Warning describing the problem.
282 */
283 public void warnDeclaredUsingPreview(DiagnosticPosition pos, Symbol sym) {
284 if (!lint.isSuppressed(LintCategory.PREVIEW))
285 preview.reportPreviewWarning(pos, Warnings.DeclaredUsingPreview(kindName(sym), sym));
286 }
287
288 /** Log a preview warning.
289 * @param pos Position to be used for error reporting.
290 * @param msg A Warning describing the problem.
291 */
292 public void warnRestrictedAPI(DiagnosticPosition pos, Symbol sym) {
293 if (lint.isEnabled(LintCategory.RESTRICTED))
294 log.warning(LintCategory.RESTRICTED, pos, Warnings.RestrictedMethod(sym.enclClass(), sym));
295 }
296
297 /** Warn about unchecked operation.
298 * @param pos Position to be used for error reporting.
299 * @param msg A string describing the problem.
300 */
301 public void warnUnchecked(DiagnosticPosition pos, Warning warnKey) {
302 if (!lint.isSuppressed(LintCategory.UNCHECKED))
303 uncheckedHandler.report(pos, warnKey);
304 }
305
306 /** Warn about unsafe vararg method decl.
307 * @param pos Position to be used for error reporting.
308 */
309 void warnUnsafeVararg(DiagnosticPosition pos, Warning warnKey) {
310 if (lint.isEnabled(LintCategory.VARARGS))
311 log.warning(LintCategory.VARARGS, pos, warnKey);
312 }
313
314 public void warnStatic(DiagnosticPosition pos, Warning warnKey) {
315 if (lint.isEnabled(LintCategory.STATIC))
316 log.warning(LintCategory.STATIC, pos, warnKey);
317 }
318
319 /** Warn about division by integer constant zero.
320 * @param pos Position to be used for error reporting.
321 */
322 void warnDivZero(DiagnosticPosition pos) {
323 if (lint.isEnabled(LintCategory.DIVZERO))
324 log.warning(LintCategory.DIVZERO, pos, Warnings.DivZero);
325 }
326
327 /**
328 * Report any deferred diagnostics.
329 */
330 public void reportDeferredDiagnostics() {
331 deprecationHandler.reportDeferredDiagnostic();
332 removalHandler.reportDeferredDiagnostic();
333 uncheckedHandler.reportDeferredDiagnostic();
334 sunApiHandler.reportDeferredDiagnostic();
335 }
336
337
338 /** Report a failure to complete a class.
339 * @param pos Position to be used for error reporting.
340 * @param ex The failure to report.
341 */
342 public Type completionError(DiagnosticPosition pos, CompletionFailure ex) {
343 log.error(JCDiagnostic.DiagnosticFlag.NON_DEFERRABLE, pos, Errors.CantAccess(ex.sym, ex.getDetailValue()));
344 return syms.errType;
345 }
346
347 /** Report an error that wrong type tag was found.
348 * @param pos Position to be used for error reporting.
349 * @param required An internationalized string describing the type tag
350 * required.
351 * @param found The type that was found.
352 */
353 Type typeTagError(DiagnosticPosition pos, JCDiagnostic required, Object found) {
354 // this error used to be raised by the parser,
355 // but has been delayed to this point:
356 if (found instanceof Type type && type.hasTag(VOID)) {
357 log.error(pos, Errors.IllegalStartOfType);
358 return syms.errType;
359 }
360 log.error(pos, Errors.TypeFoundReq(found, required));
361 return types.createErrorType(found instanceof Type type ? type : syms.errType);
362 }
363
364 /** Report duplicate declaration error.
365 */
366 void duplicateError(DiagnosticPosition pos, Symbol sym) {
367 if (!sym.type.isErroneous()) {
368 Symbol location = sym.location();
369 if (location.kind == MTH &&
370 ((MethodSymbol)location).isStaticOrInstanceInit()) {
371 log.error(pos,
372 Errors.AlreadyDefinedInClinit(kindName(sym),
373 sym,
374 kindName(sym.location()),
375 kindName(sym.location().enclClass()),
376 sym.location().enclClass()));
377 } else {
378 /* dont error if this is a duplicated parameter of a generated canonical constructor
379 * as we should have issued an error for the duplicated fields
380 */
381 if (location.kind != MTH ||
382 ((sym.owner.flags_field & GENERATEDCONSTR) == 0) ||
383 ((sym.owner.flags_field & RECORD) == 0)) {
384 log.error(pos,
385 Errors.AlreadyDefined(kindName(sym),
386 sym,
387 kindName(sym.location()),
388 sym.location()));
389 }
390 }
391 }
392 }
393
394 /** Report array/varargs duplicate declaration
395 */
396 void varargsDuplicateError(DiagnosticPosition pos, Symbol sym1, Symbol sym2) {
397 if (!sym1.type.isErroneous() && !sym2.type.isErroneous()) {
398 log.error(pos, Errors.ArrayAndVarargs(sym1, sym2, sym2.location()));
399 }
400 }
401
402 /* ************************************************************************
403 * duplicate declaration checking
404 *************************************************************************/
405
406 /** Check that variable does not hide variable with same name in
407 * immediately enclosing local scope.
408 * @param pos Position for error reporting.
409 * @param v The symbol.
410 * @param s The scope.
411 */
412 void checkTransparentVar(DiagnosticPosition pos, VarSymbol v, Scope s) {
413 for (Symbol sym : s.getSymbolsByName(v.name)) {
414 if (sym.owner != v.owner) break;
415 if (sym.kind == VAR &&
416 sym.owner.kind.matches(KindSelector.VAL_MTH) &&
417 v.name != names.error) {
418 duplicateError(pos, sym);
419 return;
420 }
421 }
422 }
423
424 /** Check that a class or interface does not hide a class or
425 * interface with same name in immediately enclosing local scope.
426 * @param pos Position for error reporting.
427 * @param c The symbol.
428 * @param s The scope.
429 */
430 void checkTransparentClass(DiagnosticPosition pos, ClassSymbol c, Scope s) {
431 for (Symbol sym : s.getSymbolsByName(c.name)) {
432 if (sym.owner != c.owner) break;
433 if (sym.kind == TYP && !sym.type.hasTag(TYPEVAR) &&
434 sym.owner.kind.matches(KindSelector.VAL_MTH) &&
435 c.name != names.error) {
436 duplicateError(pos, sym);
437 return;
438 }
439 }
440 }
441
442 /** Check that class does not have the same name as one of
443 * its enclosing classes, or as a class defined in its enclosing scope.
444 * return true if class is unique in its enclosing scope.
445 * @param pos Position for error reporting.
446 * @param name The class name.
447 * @param s The enclosing scope.
448 */
449 boolean checkUniqueClassName(DiagnosticPosition pos, Name name, Scope s) {
450 for (Symbol sym : s.getSymbolsByName(name, NON_RECURSIVE)) {
451 if (sym.kind == TYP && sym.name != names.error) {
452 duplicateError(pos, sym);
453 return false;
454 }
455 }
456 for (Symbol sym = s.owner; sym != null; sym = sym.owner) {
457 if (sym.kind == TYP && sym.name == name && sym.name != names.error &&
458 !sym.isImplicit()) {
459 duplicateError(pos, sym);
460 return true;
461 }
462 }
463 return true;
464 }
465
466 /* *************************************************************************
467 * Class name generation
468 **************************************************************************/
469
470
471 private Map<Pair<Name, Name>, Integer> localClassNameIndexes = new HashMap<>();
472
473 /** Return name of local class.
474 * This is of the form {@code <enclClass> $ n <classname> }
475 * where
476 * enclClass is the flat name of the enclosing class,
477 * classname is the simple name of the local class
478 */
479 public Name localClassName(ClassSymbol c) {
480 Name enclFlatname = c.owner.enclClass().flatname;
481 String enclFlatnameStr = enclFlatname.toString();
482 Pair<Name, Name> key = new Pair<>(enclFlatname, c.name);
483 Integer index = localClassNameIndexes.get(key);
484 for (int i = (index == null) ? 1 : index; ; i++) {
485 Name flatname = names.fromString(enclFlatnameStr
486 + syntheticNameChar + i + c.name);
487 if (getCompiled(c.packge().modle, flatname) == null) {
488 localClassNameIndexes.put(key, i + 1);
489 return flatname;
490 }
491 }
492 }
493
494 public void clearLocalClassNameIndexes(ClassSymbol c) {
495 if (c.owner != null && c.owner.kind != NIL) {
496 localClassNameIndexes.remove(new Pair<>(
497 c.owner.enclClass().flatname, c.name));
498 }
499 }
500
501 public void newRound() {
502 compiled.clear();
503 localClassNameIndexes.clear();
504 }
505
506 public void clear() {
507 deprecationHandler.clear();
508 removalHandler.clear();
509 uncheckedHandler.clear();
510 sunApiHandler.clear();
511 }
512
513 public void putCompiled(ClassSymbol csym) {
514 compiled.put(Pair.of(csym.packge().modle, csym.flatname), csym);
515 }
516
517 public ClassSymbol getCompiled(ClassSymbol csym) {
518 return compiled.get(Pair.of(csym.packge().modle, csym.flatname));
519 }
520
521 public ClassSymbol getCompiled(ModuleSymbol msym, Name flatname) {
522 return compiled.get(Pair.of(msym, flatname));
523 }
524
525 public void removeCompiled(ClassSymbol csym) {
526 compiled.remove(Pair.of(csym.packge().modle, csym.flatname));
527 }
528
529 /* *************************************************************************
530 * Type Checking
531 **************************************************************************/
532
533 /**
534 * A check context is an object that can be used to perform compatibility
535 * checks - depending on the check context, meaning of 'compatibility' might
536 * vary significantly.
537 */
538 public interface CheckContext {
539 /**
540 * Is type 'found' compatible with type 'req' in given context
541 */
542 boolean compatible(Type found, Type req, Warner warn);
543 /**
544 * Report a check error
545 */
546 void report(DiagnosticPosition pos, JCDiagnostic details);
547 /**
548 * Obtain a warner for this check context
549 */
550 public Warner checkWarner(DiagnosticPosition pos, Type found, Type req);
551
552 public InferenceContext inferenceContext();
553
554 public DeferredAttr.DeferredAttrContext deferredAttrContext();
555 }
556
557 /**
558 * This class represent a check context that is nested within another check
559 * context - useful to check sub-expressions. The default behavior simply
560 * redirects all method calls to the enclosing check context leveraging
561 * the forwarding pattern.
562 */
563 static class NestedCheckContext implements CheckContext {
564 CheckContext enclosingContext;
565
566 NestedCheckContext(CheckContext enclosingContext) {
567 this.enclosingContext = enclosingContext;
568 }
569
570 public boolean compatible(Type found, Type req, Warner warn) {
571 return enclosingContext.compatible(found, req, warn);
572 }
573
574 public void report(DiagnosticPosition pos, JCDiagnostic details) {
575 enclosingContext.report(pos, details);
576 }
577
578 public Warner checkWarner(DiagnosticPosition pos, Type found, Type req) {
579 return enclosingContext.checkWarner(pos, found, req);
580 }
581
582 public InferenceContext inferenceContext() {
583 return enclosingContext.inferenceContext();
584 }
585
586 public DeferredAttrContext deferredAttrContext() {
587 return enclosingContext.deferredAttrContext();
588 }
589 }
590
591 /**
592 * Check context to be used when evaluating assignment/return statements
593 */
594 CheckContext basicHandler = new CheckContext() {
595 public void report(DiagnosticPosition pos, JCDiagnostic details) {
596 log.error(pos, Errors.ProbFoundReq(details));
597 }
598 public boolean compatible(Type found, Type req, Warner warn) {
599 return types.isAssignable(found, req, warn);
600 }
601
602 public Warner checkWarner(DiagnosticPosition pos, Type found, Type req) {
603 return convertWarner(pos, found, req);
604 }
605
606 public InferenceContext inferenceContext() {
607 return infer.emptyContext;
608 }
609
610 public DeferredAttrContext deferredAttrContext() {
611 return deferredAttr.emptyDeferredAttrContext;
612 }
613
614 @Override
615 public String toString() {
616 return "CheckContext: basicHandler";
617 }
618 };
619
620 /** Check that a given type is assignable to a given proto-type.
621 * If it is, return the type, otherwise return errType.
622 * @param pos Position to be used for error reporting.
623 * @param found The type that was found.
624 * @param req The type that was required.
625 */
626 public Type checkType(DiagnosticPosition pos, Type found, Type req) {
627 return checkType(pos, found, req, basicHandler);
628 }
629
630 Type checkType(final DiagnosticPosition pos, final Type found, final Type req, final CheckContext checkContext) {
631 final InferenceContext inferenceContext = checkContext.inferenceContext();
632 if (inferenceContext.free(req) || inferenceContext.free(found)) {
633 inferenceContext.addFreeTypeListener(List.of(req, found),
634 solvedContext -> checkType(pos, solvedContext.asInstType(found), solvedContext.asInstType(req), checkContext));
635 }
636 if (req.hasTag(ERROR))
637 return req;
638 if (req.hasTag(NONE))
639 return found;
640 if (checkContext.compatible(found, req, checkContext.checkWarner(pos, found, req))) {
641 return found;
642 } else {
643 if (found.isNumeric() && req.isNumeric()) {
644 checkContext.report(pos, diags.fragment(Fragments.PossibleLossOfPrecision(found, req)));
645 return types.createErrorType(found);
646 }
647 checkContext.report(pos, diags.fragment(Fragments.InconvertibleTypes(found, req)));
648 return types.createErrorType(found);
649 }
650 }
651
652 /** Check that a given type can be cast to a given target type.
653 * Return the result of the cast.
654 * @param pos Position to be used for error reporting.
655 * @param found The type that is being cast.
656 * @param req The target type of the cast.
657 */
658 Type checkCastable(DiagnosticPosition pos, Type found, Type req) {
659 return checkCastable(pos, found, req, basicHandler);
660 }
661 Type checkCastable(DiagnosticPosition pos, Type found, Type req, CheckContext checkContext) {
662 if (types.isCastable(found, req, castWarner(pos, found, req))) {
663 return req;
664 } else {
665 checkContext.report(pos, diags.fragment(Fragments.InconvertibleTypes(found, req)));
666 return types.createErrorType(found);
667 }
668 }
669
670 /** Check for redundant casts (i.e. where source type is a subtype of target type)
671 * The problem should only be reported for non-292 cast
672 */
673 public void checkRedundantCast(Env<AttrContext> env, final JCTypeCast tree) {
674 if (!tree.type.isErroneous()
675 && types.isSameType(tree.expr.type, tree.clazz.type)
676 && !(ignoreAnnotatedCasts && TreeInfo.containsTypeAnnotation(tree.clazz))
677 && !is292targetTypeCast(tree)) {
678 deferredLintHandler.report(() -> {
679 if (lint.isEnabled(LintCategory.CAST))
680 log.warning(LintCategory.CAST,
681 tree.pos(), Warnings.RedundantCast(tree.clazz.type));
682 });
683 }
684 }
685 //where
686 private boolean is292targetTypeCast(JCTypeCast tree) {
687 boolean is292targetTypeCast = false;
688 JCExpression expr = TreeInfo.skipParens(tree.expr);
689 if (expr.hasTag(APPLY)) {
690 JCMethodInvocation apply = (JCMethodInvocation)expr;
691 Symbol sym = TreeInfo.symbol(apply.meth);
692 is292targetTypeCast = sym != null &&
693 sym.kind == MTH &&
694 (sym.flags() & HYPOTHETICAL) != 0;
695 }
696 return is292targetTypeCast;
697 }
698
699 private static final boolean ignoreAnnotatedCasts = true;
700
701 /** Check that a type is within some bounds.
702 *
703 * Used in TypeApply to verify that, e.g., X in {@code V<X>} is a valid
704 * type argument.
705 * @param a The type that should be bounded by bs.
706 * @param bound The bound.
707 */
708 private boolean checkExtends(Type a, Type bound) {
709 if (a.isUnbound()) {
710 return true;
711 } else if (!a.hasTag(WILDCARD)) {
712 a = types.cvarUpperBound(a);
713 return types.isSubtype(a, bound);
714 } else if (a.isExtendsBound()) {
715 return types.isCastable(bound, types.wildUpperBound(a), types.noWarnings);
716 } else if (a.isSuperBound()) {
717 return !types.notSoftSubtype(types.wildLowerBound(a), bound);
718 }
719 return true;
720 }
721
722 /** Check that type is different from 'void'.
723 * @param pos Position to be used for error reporting.
724 * @param t The type to be checked.
725 */
726 Type checkNonVoid(DiagnosticPosition pos, Type t) {
727 if (t.hasTag(VOID)) {
728 log.error(pos, Errors.VoidNotAllowedHere);
729 return types.createErrorType(t);
730 } else {
731 return t;
732 }
733 }
734
735 Type checkClassOrArrayType(DiagnosticPosition pos, Type t) {
736 if (!t.hasTag(CLASS) && !t.hasTag(ARRAY) && !t.hasTag(ERROR)) {
737 return typeTagError(pos,
738 diags.fragment(Fragments.TypeReqClassArray),
739 asTypeParam(t));
740 } else {
741 return t;
742 }
743 }
744
745 /** Check that type is a class or interface type.
746 * @param pos Position to be used for error reporting.
747 * @param t The type to be checked.
748 */
749 Type checkClassType(DiagnosticPosition pos, Type t) {
750 if (!t.hasTag(CLASS) && !t.hasTag(ERROR)) {
751 return typeTagError(pos,
752 diags.fragment(Fragments.TypeReqClass),
753 asTypeParam(t));
754 } else {
755 return t;
756 }
757 }
758 //where
759 private Object asTypeParam(Type t) {
760 return (t.hasTag(TYPEVAR))
761 ? diags.fragment(Fragments.TypeParameter(t))
762 : t;
763 }
764
765 void checkConstraintsOfValueClass(JCClassDecl tree, ClassSymbol c) {
766 DiagnosticPosition pos = tree.pos();
767 for (Type st : types.closure(c.type)) {
768 if (st == null || st.tsym == null || st.tsym.kind == ERR)
769 continue;
770 if (st.tsym == syms.objectType.tsym || st.tsym == syms.recordType.tsym || st.isInterface())
771 continue;
772 if (!st.tsym.isAbstract()) {
773 if (c != st.tsym) {
774 log.error(pos, Errors.ConcreteSupertypeForValueClass(c, st));
775 }
776 continue;
777 }
778 // dealing with an abstract value or value super class below.
779 for (Symbol s : st.tsym.members().getSymbols(NON_RECURSIVE)) {
780 if (s.kind == MTH) {
781 if ((s.flags() & (SYNCHRONIZED | STATIC)) == SYNCHRONIZED) {
782 log.error(pos, Errors.SuperClassMethodCannotBeSynchronized(s, c, st));
783 }
784 break;
785 }
786 }
787 }
788 }
789
790 /** Check that type is a valid qualifier for a constructor reference expression
791 */
792 Type checkConstructorRefType(DiagnosticPosition pos, Type t) {
793 t = checkClassOrArrayType(pos, t);
794 if (t.hasTag(CLASS)) {
795 if ((t.tsym.flags() & (ABSTRACT | INTERFACE)) != 0) {
796 log.error(pos, Errors.AbstractCantBeInstantiated(t.tsym));
797 t = types.createErrorType(t);
798 } else if ((t.tsym.flags() & ENUM) != 0) {
799 log.error(pos, Errors.EnumCantBeInstantiated);
800 t = types.createErrorType(t);
801 } else {
802 t = checkClassType(pos, t, true);
803 }
804 } else if (t.hasTag(ARRAY)) {
805 if (!types.isReifiable(((ArrayType)t).elemtype)) {
806 log.error(pos, Errors.GenericArrayCreation);
807 t = types.createErrorType(t);
808 }
809 }
810 return t;
811 }
812
813 /** Check that type is a class or interface type.
814 * @param pos Position to be used for error reporting.
815 * @param t The type to be checked.
816 * @param noBounds True if type bounds are illegal here.
817 */
818 Type checkClassType(DiagnosticPosition pos, Type t, boolean noBounds) {
819 t = checkClassType(pos, t);
820 if (noBounds && t.isParameterized()) {
821 List<Type> args = t.getTypeArguments();
822 while (args.nonEmpty()) {
823 if (args.head.hasTag(WILDCARD))
824 return typeTagError(pos,
825 diags.fragment(Fragments.TypeReqExact),
826 args.head);
827 args = args.tail;
828 }
829 }
830 return t;
831 }
832
833 /** Check that type is a reference type, i.e. a class, interface or array type
834 * or a type variable.
835 * @param pos Position to be used for error reporting.
836 * @param t The type to be checked.
837 */
838 Type checkRefType(DiagnosticPosition pos, Type t) {
839 if (t.isReference())
840 return t;
841 else
842 return typeTagError(pos,
843 diags.fragment(Fragments.TypeReqRef),
844 t);
845 }
846
847 /** Check that type is an identity type, i.e. not a value type.
848 * When not discernible statically, give it the benefit of doubt
849 * and defer to runtime.
850 *
851 * @param pos Position to be used for error reporting.
852 * @param t The type to be checked.
853 */
854 boolean checkIdentityType(DiagnosticPosition pos, Type t) {
855 if (t.hasTag(TYPEVAR)) {
856 t = types.skipTypeVars(t, false);
857 }
858 if (t.isIntersection()) {
859 IntersectionClassType ict = (IntersectionClassType)t;
860 boolean result = true;
861 for (Type component : ict.getExplicitComponents()) {
862 result &= checkIdentityType(pos, component);
863 }
864 return result;
865 }
866 if (t.isPrimitive() || (t.isValueClass() && !t.tsym.isAbstract())) {
867 typeTagError(pos, diags.fragment(Fragments.TypeReqIdentity), t);
868 return false;
869 }
870 return true;
871 }
872
873 /** Check that each type is a reference type, i.e. a class, interface or array type
874 * or a type variable.
875 * @param trees Original trees, used for error reporting.
876 * @param types The types to be checked.
877 */
878 List<Type> checkRefTypes(List<JCExpression> trees, List<Type> types) {
879 List<JCExpression> tl = trees;
880 for (List<Type> l = types; l.nonEmpty(); l = l.tail) {
881 l.head = checkRefType(tl.head.pos(), l.head);
882 tl = tl.tail;
883 }
884 return types;
885 }
886
887 /** Check that type is a null or reference type.
888 * @param pos Position to be used for error reporting.
889 * @param t The type to be checked.
890 */
891 Type checkNullOrRefType(DiagnosticPosition pos, Type t) {
892 if (t.isReference() || t.hasTag(BOT))
893 return t;
894 else
895 return typeTagError(pos,
896 diags.fragment(Fragments.TypeReqRef),
897 t);
898 }
899
900 /** Check that flag set does not contain elements of two conflicting sets. s
901 * Return true if it doesn't.
902 * @param pos Position to be used for error reporting.
903 * @param flags The set of flags to be checked.
904 * @param set1 Conflicting flags set #1.
905 * @param set2 Conflicting flags set #2.
906 */
907 boolean checkDisjoint(DiagnosticPosition pos, long flags, long set1, long set2) {
908 if ((flags & set1) != 0 && (flags & set2) != 0) {
909 log.error(pos,
910 Errors.IllegalCombinationOfModifiers(asFlagSet(TreeInfo.firstFlag(flags & set1)),
911 asFlagSet(TreeInfo.firstFlag(flags & set2))));
912 return false;
913 } else
914 return true;
915 }
916
917 /** Check that usage of diamond operator is correct (i.e. diamond should not
918 * be used with non-generic classes or in anonymous class creation expressions)
919 */
920 Type checkDiamond(JCNewClass tree, Type t) {
921 if (!TreeInfo.isDiamond(tree) ||
922 t.isErroneous()) {
923 return checkClassType(tree.clazz.pos(), t, true);
924 } else {
925 if (tree.def != null && !Feature.DIAMOND_WITH_ANONYMOUS_CLASS_CREATION.allowedInSource(source)) {
926 log.error(DiagnosticFlag.SOURCE_LEVEL, tree.clazz.pos(),
927 Errors.CantApplyDiamond1(t, Feature.DIAMOND_WITH_ANONYMOUS_CLASS_CREATION.fragment(source.name)));
928 }
929 if (t.tsym.type.getTypeArguments().isEmpty()) {
930 log.error(tree.clazz.pos(),
931 Errors.CantApplyDiamond1(t,
932 Fragments.DiamondNonGeneric(t)));
933 return types.createErrorType(t);
934 } else if (tree.typeargs != null &&
935 tree.typeargs.nonEmpty()) {
936 log.error(tree.clazz.pos(),
937 Errors.CantApplyDiamond1(t,
938 Fragments.DiamondAndExplicitParams(t)));
939 return types.createErrorType(t);
940 } else {
941 return t;
942 }
943 }
944 }
945
946 /** Check that the type inferred using the diamond operator does not contain
947 * non-denotable types such as captured types or intersection types.
948 * @param t the type inferred using the diamond operator
949 * @return the (possibly empty) list of non-denotable types.
950 */
951 List<Type> checkDiamondDenotable(ClassType t) {
952 ListBuffer<Type> buf = new ListBuffer<>();
953 for (Type arg : t.allparams()) {
954 if (!checkDenotable(arg)) {
955 buf.append(arg);
956 }
957 }
958 return buf.toList();
959 }
960
961 public boolean checkDenotable(Type t) {
962 return denotableChecker.visit(t, null);
963 }
964 // where
965
966 /** diamondTypeChecker: A type visitor that descends down the given type looking for non-denotable
967 * types. The visit methods return false as soon as a non-denotable type is encountered and true
968 * otherwise.
969 */
970 private static final Types.SimpleVisitor<Boolean, Void> denotableChecker = new Types.SimpleVisitor<Boolean, Void>() {
971 @Override
972 public Boolean visitType(Type t, Void s) {
973 return true;
974 }
975 @Override
976 public Boolean visitClassType(ClassType t, Void s) {
977 if (t.isUnion() || t.isIntersection()) {
978 return false;
979 }
980 for (Type targ : t.allparams()) {
981 if (!visit(targ, s)) {
982 return false;
983 }
984 }
985 return true;
986 }
987
988 @Override
989 public Boolean visitTypeVar(TypeVar t, Void s) {
990 /* Any type variable mentioned in the inferred type must have been declared as a type parameter
991 (i.e cannot have been produced by inference (18.4))
992 */
993 return (t.tsym.flags() & SYNTHETIC) == 0;
994 }
995
996 @Override
997 public Boolean visitCapturedType(CapturedType t, Void s) {
998 /* Any type variable mentioned in the inferred type must have been declared as a type parameter
999 (i.e cannot have been produced by capture conversion (5.1.10))
1000 */
1001 return false;
1002 }
1003
1004 @Override
1005 public Boolean visitArrayType(ArrayType t, Void s) {
1006 return visit(t.elemtype, s);
1007 }
1008
1009 @Override
1010 public Boolean visitWildcardType(WildcardType t, Void s) {
1011 return visit(t.type, s);
1012 }
1013 };
1014
1015 void checkVarargsMethodDecl(Env<AttrContext> env, JCMethodDecl tree) {
1016 MethodSymbol m = tree.sym;
1017 boolean hasTrustMeAnno = m.attribute(syms.trustMeType.tsym) != null;
1018 Type varargElemType = null;
1019 if (m.isVarArgs()) {
1020 varargElemType = types.elemtype(tree.params.last().type);
1021 }
1022 if (hasTrustMeAnno && !isTrustMeAllowedOnMethod(m)) {
1023 if (varargElemType != null) {
1024 JCDiagnostic msg = Feature.PRIVATE_SAFE_VARARGS.allowedInSource(source) ?
1025 diags.fragment(Fragments.VarargsTrustmeOnVirtualVarargs(m)) :
1026 diags.fragment(Fragments.VarargsTrustmeOnVirtualVarargsFinalOnly(m));
1027 log.error(tree,
1028 Errors.VarargsInvalidTrustmeAnno(syms.trustMeType.tsym,
1029 msg));
1030 } else {
1031 log.error(tree,
1032 Errors.VarargsInvalidTrustmeAnno(syms.trustMeType.tsym,
1033 Fragments.VarargsTrustmeOnNonVarargsMeth(m)));
1034 }
1035 } else if (hasTrustMeAnno && varargElemType != null &&
1036 types.isReifiable(varargElemType)) {
1037 warnUnsafeVararg(tree, Warnings.VarargsRedundantTrustmeAnno(
1038 syms.trustMeType.tsym,
1039 diags.fragment(Fragments.VarargsTrustmeOnReifiableVarargs(varargElemType))));
1040 }
1041 else if (!hasTrustMeAnno && varargElemType != null &&
1042 !types.isReifiable(varargElemType)) {
1043 warnUnchecked(tree.params.head.pos(), Warnings.UncheckedVarargsNonReifiableType(varargElemType));
1044 }
1045 }
1046 //where
1047 private boolean isTrustMeAllowedOnMethod(Symbol s) {
1048 return (s.flags() & VARARGS) != 0 &&
1049 (s.isConstructor() ||
1050 (s.flags() & (STATIC | FINAL |
1051 (Feature.PRIVATE_SAFE_VARARGS.allowedInSource(source) ? PRIVATE : 0) )) != 0);
1052 }
1053
1054 Type checkLocalVarType(DiagnosticPosition pos, Type t, Name name) {
1055 //check that resulting type is not the null type
1056 if (t.hasTag(BOT)) {
1057 log.error(pos, Errors.CantInferLocalVarType(name, Fragments.LocalCantInferNull));
1058 return types.createErrorType(t);
1059 } else if (t.hasTag(VOID)) {
1060 log.error(pos, Errors.CantInferLocalVarType(name, Fragments.LocalCantInferVoid));
1061 return types.createErrorType(t);
1062 }
1063
1064 //upward project the initializer type
1065 return types.upward(t, types.captures(t)).baseType();
1066 }
1067
1068 Type checkMethod(final Type mtype,
1069 final Symbol sym,
1070 final Env<AttrContext> env,
1071 final List<JCExpression> argtrees,
1072 final List<Type> argtypes,
1073 final boolean useVarargs,
1074 InferenceContext inferenceContext) {
1075 // System.out.println("call : " + env.tree);
1076 // System.out.println("method : " + owntype);
1077 // System.out.println("actuals: " + argtypes);
1078 if (inferenceContext.free(mtype)) {
1079 inferenceContext.addFreeTypeListener(List.of(mtype),
1080 solvedContext -> checkMethod(solvedContext.asInstType(mtype), sym, env, argtrees, argtypes, useVarargs, solvedContext));
1081 return mtype;
1082 }
1083 Type owntype = mtype;
1084 List<Type> formals = owntype.getParameterTypes();
1085 List<Type> nonInferred = sym.type.getParameterTypes();
1086 if (nonInferred.length() != formals.length()) nonInferred = formals;
1087 Type last = useVarargs ? formals.last() : null;
1088 if (sym.name == names.init && sym.owner == syms.enumSym) {
1089 formals = formals.tail.tail;
1090 nonInferred = nonInferred.tail.tail;
1091 }
1092 if ((sym.flags() & ANONCONSTR_BASED) != 0) {
1093 formals = formals.tail;
1094 nonInferred = nonInferred.tail;
1095 }
1096 List<JCExpression> args = argtrees;
1097 if (args != null) {
1098 //this is null when type-checking a method reference
1099 while (formals.head != last) {
1100 JCTree arg = args.head;
1101 Warner warn = convertWarner(arg.pos(), arg.type, nonInferred.head);
1102 assertConvertible(arg, arg.type, formals.head, warn);
1103 args = args.tail;
1104 formals = formals.tail;
1105 nonInferred = nonInferred.tail;
1106 }
1107 if (useVarargs) {
1108 Type varArg = types.elemtype(last);
1109 while (args.tail != null) {
1110 JCTree arg = args.head;
1111 Warner warn = convertWarner(arg.pos(), arg.type, varArg);
1112 assertConvertible(arg, arg.type, varArg, warn);
1113 args = args.tail;
1114 }
1115 } else if ((sym.flags() & (VARARGS | SIGNATURE_POLYMORPHIC)) == VARARGS) {
1116 // non-varargs call to varargs method
1117 Type varParam = owntype.getParameterTypes().last();
1118 Type lastArg = argtypes.last();
1119 if (types.isSubtypeUnchecked(lastArg, types.elemtype(varParam)) &&
1120 !types.isSameType(types.erasure(varParam), types.erasure(lastArg)))
1121 log.warning(argtrees.last().pos(),
1122 Warnings.InexactNonVarargsCall(types.elemtype(varParam),varParam));
1123 }
1124 }
1125 if (useVarargs) {
1126 Type argtype = owntype.getParameterTypes().last();
1127 if (!types.isReifiable(argtype) &&
1128 (sym.baseSymbol().attribute(syms.trustMeType.tsym) == null ||
1129 !isTrustMeAllowedOnMethod(sym))) {
1130 warnUnchecked(env.tree.pos(), Warnings.UncheckedGenericArrayCreation(argtype));
1131 }
1132 TreeInfo.setVarargsElement(env.tree, types.elemtype(argtype));
1133 }
1134 return owntype;
1135 }
1136 //where
1137 private void assertConvertible(JCTree tree, Type actual, Type formal, Warner warn) {
1138 if (types.isConvertible(actual, formal, warn))
1139 return;
1140
1141 if (formal.isCompound()
1142 && types.isSubtype(actual, types.supertype(formal))
1143 && types.isSubtypeUnchecked(actual, types.interfaces(formal), warn))
1144 return;
1145 }
1146
1147 /**
1148 * Check that type 't' is a valid instantiation of a generic class
1149 * (see JLS 4.5)
1150 *
1151 * @param t class type to be checked
1152 * @return true if 't' is well-formed
1153 */
1154 public boolean checkValidGenericType(Type t) {
1155 return firstIncompatibleTypeArg(t) == null;
1156 }
1157 //WHERE
1158 private Type firstIncompatibleTypeArg(Type type) {
1159 List<Type> formals = type.tsym.type.allparams();
1160 List<Type> actuals = type.allparams();
1161 List<Type> args = type.getTypeArguments();
1162 List<Type> forms = type.tsym.type.getTypeArguments();
1163 ListBuffer<Type> bounds_buf = new ListBuffer<>();
1164
1165 // For matching pairs of actual argument types `a' and
1166 // formal type parameters with declared bound `b' ...
1167 while (args.nonEmpty() && forms.nonEmpty()) {
1168 // exact type arguments needs to know their
1169 // bounds (for upper and lower bound
1170 // calculations). So we create new bounds where
1171 // type-parameters are replaced with actuals argument types.
1172 bounds_buf.append(types.subst(forms.head.getUpperBound(), formals, actuals));
1173 args = args.tail;
1174 forms = forms.tail;
1175 }
1176
1177 args = type.getTypeArguments();
1178 List<Type> tvars_cap = types.substBounds(formals,
1179 formals,
1180 types.capture(type).allparams());
1181 while (args.nonEmpty() && tvars_cap.nonEmpty()) {
1182 // Let the actual arguments know their bound
1183 args.head.withTypeVar((TypeVar)tvars_cap.head);
1184 args = args.tail;
1185 tvars_cap = tvars_cap.tail;
1186 }
1187
1188 args = type.getTypeArguments();
1189 List<Type> bounds = bounds_buf.toList();
1190
1191 while (args.nonEmpty() && bounds.nonEmpty()) {
1192 Type actual = args.head;
1193 if (!isTypeArgErroneous(actual) &&
1194 !bounds.head.isErroneous() &&
1195 !checkExtends(actual, bounds.head)) {
1196 return args.head;
1197 }
1198 args = args.tail;
1199 bounds = bounds.tail;
1200 }
1201
1202 args = type.getTypeArguments();
1203 bounds = bounds_buf.toList();
1204
1205 for (Type arg : types.capture(type).getTypeArguments()) {
1206 if (arg.hasTag(TYPEVAR) &&
1207 arg.getUpperBound().isErroneous() &&
1208 !bounds.head.isErroneous() &&
1209 !isTypeArgErroneous(args.head)) {
1210 return args.head;
1211 }
1212 bounds = bounds.tail;
1213 args = args.tail;
1214 }
1215
1216 return null;
1217 }
1218 //where
1219 boolean isTypeArgErroneous(Type t) {
1220 return isTypeArgErroneous.visit(t);
1221 }
1222
1223 Types.UnaryVisitor<Boolean> isTypeArgErroneous = new Types.UnaryVisitor<Boolean>() {
1224 public Boolean visitType(Type t, Void s) {
1225 return t.isErroneous();
1226 }
1227 @Override
1228 public Boolean visitTypeVar(TypeVar t, Void s) {
1229 return visit(t.getUpperBound());
1230 }
1231 @Override
1232 public Boolean visitCapturedType(CapturedType t, Void s) {
1233 return visit(t.getUpperBound()) ||
1234 visit(t.getLowerBound());
1235 }
1236 @Override
1237 public Boolean visitWildcardType(WildcardType t, Void s) {
1238 return visit(t.type);
1239 }
1240 };
1241
1242 /** Check that given modifiers are legal for given symbol and
1243 * return modifiers together with any implicit modifiers for that symbol.
1244 * Warning: we can't use flags() here since this method
1245 * is called during class enter, when flags() would cause a premature
1246 * completion.
1247 * @param pos Position to be used for error reporting.
1248 * @param flags The set of modifiers given in a definition.
1249 * @param sym The defined symbol.
1250 */
1251 long checkFlags(DiagnosticPosition pos, long flags, Symbol sym, JCTree tree) {
1252 long mask;
1253 long implicit = 0;
1254
1255 switch (sym.kind) {
1256 case VAR:
1257 if (TreeInfo.isReceiverParam(tree))
1258 mask = ReceiverParamFlags;
1259 else if (sym.owner.kind != TYP)
1260 mask = LocalVarFlags;
1261 else if ((sym.owner.flags_field & INTERFACE) != 0)
1262 mask = implicit = InterfaceVarFlags;
1263 else {
1264 boolean isInstanceFieldOfValueClass = sym.owner.type.isValueClass() && (flags & STATIC) == 0;
1265 mask = !isInstanceFieldOfValueClass ? VarFlags : ExtendedVarFlags;
1266 if (isInstanceFieldOfValueClass) {
1267 implicit |= FINAL | STRICT;
1268 }
1269 }
1270 break;
1271 case MTH:
1272 if (sym.name == names.init) {
1273 if ((sym.owner.flags_field & ENUM) != 0) {
1274 // enum constructors cannot be declared public or
1275 // protected and must be implicitly or explicitly
1276 // private
1277 implicit = PRIVATE;
1278 mask = PRIVATE;
1279 } else
1280 mask = ConstructorFlags;
1281 } else if ((sym.owner.flags_field & INTERFACE) != 0) {
1282 if ((sym.owner.flags_field & ANNOTATION) != 0) {
1283 mask = AnnotationTypeElementMask;
1284 implicit = PUBLIC | ABSTRACT;
1285 } else if ((flags & (DEFAULT | STATIC | PRIVATE)) != 0) {
1286 mask = InterfaceMethodMask;
1287 implicit = (flags & PRIVATE) != 0 ? 0 : PUBLIC;
1288 if ((flags & DEFAULT) != 0) {
1289 implicit |= ABSTRACT;
1290 }
1291 } else {
1292 mask = implicit = InterfaceMethodFlags;
1293 }
1294 } else if ((sym.owner.flags_field & RECORD) != 0) {
1295 mask = ((sym.owner.flags_field & VALUE_CLASS) != 0 && (flags & Flags.STATIC) == 0) ?
1296 RecordMethodFlags & ~SYNCHRONIZED : RecordMethodFlags;
1297 } else {
1298 // value objects do not have an associated monitor/lock
1299 mask = ((sym.owner.flags_field & VALUE_CLASS) != 0 && (flags & Flags.STATIC) == 0) ?
1300 MethodFlags & ~SYNCHRONIZED : MethodFlags;
1301 }
1302 if ((flags & STRICTFP) != 0) {
1303 warnOnExplicitStrictfp(pos);
1304 }
1305 // Imply STRICTFP if owner has STRICTFP set.
1306 if (((flags|implicit) & Flags.ABSTRACT) == 0 ||
1307 ((flags) & Flags.DEFAULT) != 0)
1308 implicit |= sym.owner.flags_field & STRICTFP;
1309 break;
1310 case TYP:
1311 if (sym.owner.kind.matches(KindSelector.VAL_MTH) ||
1312 (sym.isDirectlyOrIndirectlyLocal() && (flags & ANNOTATION) != 0)) {
1313 boolean implicitlyStatic = !sym.isAnonymous() &&
1314 ((flags & RECORD) != 0 || (flags & ENUM) != 0 || (flags & INTERFACE) != 0);
1315 boolean staticOrImplicitlyStatic = (flags & STATIC) != 0 || implicitlyStatic;
1316 // local statics are allowed only if records are allowed too
1317 mask = staticOrImplicitlyStatic && allowRecords && (flags & ANNOTATION) == 0 ? ExtendedStaticLocalClassFlags : ExtendedLocalClassFlags;
1318 implicit = implicitlyStatic ? STATIC : implicit;
1319 } else if (sym.owner.kind == TYP) {
1320 // statics in inner classes are allowed only if records are allowed too
1321 mask = ((flags & STATIC) != 0) && allowRecords && (flags & ANNOTATION) == 0 ? ExtendedMemberStaticClassFlags : ExtendedMemberClassFlags;
1322 if (sym.owner.owner.kind == PCK ||
1323 (sym.owner.flags_field & STATIC) != 0) {
1324 mask |= STATIC;
1325 } else if (!allowRecords && ((flags & ENUM) != 0 || (flags & RECORD) != 0)) {
1326 log.error(pos, Errors.StaticDeclarationNotAllowedInInnerClasses);
1327 }
1328 // Nested interfaces and enums are always STATIC (Spec ???)
1329 if ((flags & (INTERFACE | ENUM | RECORD)) != 0 ) implicit = STATIC;
1330 } else {
1331 mask = ExtendedClassFlags;
1332 }
1333 // Interfaces are always ABSTRACT
1334 if ((flags & INTERFACE) != 0) implicit |= ABSTRACT;
1335
1336 if ((flags & (INTERFACE | VALUE_CLASS)) == 0) {
1337 implicit |= IDENTITY_TYPE;
1338 }
1339
1340 if ((flags & ENUM) != 0) {
1341 // enums can't be declared abstract, final, sealed or non-sealed or value
1342 mask &= ~(ABSTRACT | FINAL | SEALED | NON_SEALED | VALUE_CLASS);
1343 implicit |= implicitEnumFinalFlag(tree);
1344 }
1345 if ((flags & RECORD) != 0) {
1346 // records can't be declared abstract
1347 mask &= ~ABSTRACT;
1348 implicit |= FINAL;
1349 }
1350 if ((flags & STRICTFP) != 0) {
1351 warnOnExplicitStrictfp(pos);
1352 }
1353 // Imply STRICTFP if owner has STRICTFP set.
1354 implicit |= sym.owner.flags_field & STRICTFP;
1355
1356 // concrete value classes are implicitly final
1357 if ((flags & (ABSTRACT | INTERFACE | VALUE_CLASS)) == VALUE_CLASS) {
1358 implicit |= FINAL;
1359 }
1360 break;
1361 default:
1362 throw new AssertionError();
1363 }
1364 long illegal = flags & ExtendedStandardFlags & ~mask;
1365 if (illegal != 0) {
1366 if ((illegal & INTERFACE) != 0) {
1367 log.error(pos, ((flags & ANNOTATION) != 0) ? Errors.AnnotationDeclNotAllowedHere : Errors.IntfNotAllowedHere);
1368 mask |= INTERFACE;
1369 }
1370 else {
1371 log.error(pos,
1372 Errors.ModNotAllowedHere(asFlagSet(illegal)));
1373 }
1374 }
1375 else if ((sym.kind == TYP ||
1376 // ISSUE: Disallowing abstract&private is no longer appropriate
1377 // in the presence of inner classes. Should it be deleted here?
1378 checkDisjoint(pos, flags,
1379 ABSTRACT,
1380 PRIVATE | STATIC | DEFAULT))
1381 &&
1382 checkDisjoint(pos, flags,
1383 STATIC | PRIVATE,
1384 DEFAULT)
1385 &&
1386 checkDisjoint(pos, flags,
1387 ABSTRACT | INTERFACE,
1388 FINAL | NATIVE | SYNCHRONIZED)
1389 &&
1390 checkDisjoint(pos, flags,
1391 PUBLIC,
1392 PRIVATE | PROTECTED)
1393 &&
1394 checkDisjoint(pos, flags,
1395 PRIVATE,
1396 PUBLIC | PROTECTED)
1397 &&
1398 checkDisjoint(pos, flags,
1399 FINAL,
1400 VOLATILE)
1401 &&
1402 (sym.kind == TYP ||
1403 checkDisjoint(pos, flags,
1404 ABSTRACT | NATIVE,
1405 STRICTFP))
1406 && checkDisjoint(pos, flags,
1407 FINAL,
1408 SEALED | NON_SEALED)
1409 && checkDisjoint(pos, flags,
1410 SEALED,
1411 FINAL | NON_SEALED)
1412 && checkDisjoint(pos, flags,
1413 SEALED,
1414 ANNOTATION)
1415 && checkDisjoint(pos, flags,
1416 VALUE_CLASS,
1417 ANNOTATION)
1418 && checkDisjoint(pos, flags,
1419 VALUE_CLASS,
1420 NON_SEALED)
1421 && checkDisjoint(pos, flags,
1422 VALUE_CLASS,
1423 INTERFACE) ) {
1424 // skip
1425 }
1426 return flags & (mask | ~ExtendedStandardFlags) | implicit;
1427 }
1428
1429 private void warnOnExplicitStrictfp(DiagnosticPosition pos) {
1430 DiagnosticPosition prevLintPos = deferredLintHandler.setPos(pos);
1431 try {
1432 deferredLintHandler.report(() -> {
1433 if (lint.isEnabled(LintCategory.STRICTFP)) {
1434 log.warning(LintCategory.STRICTFP,
1435 pos, Warnings.Strictfp); }
1436 });
1437 } finally {
1438 deferredLintHandler.setPos(prevLintPos);
1439 }
1440 }
1441
1442
1443 /** Determine if this enum should be implicitly final.
1444 *
1445 * If the enum has no specialized enum constants, it is final.
1446 *
1447 * If the enum does have specialized enum constants, it is
1448 * <i>not</i> final.
1449 */
1450 private long implicitEnumFinalFlag(JCTree tree) {
1451 if (!tree.hasTag(CLASSDEF)) return 0;
1452 class SpecialTreeVisitor extends JCTree.Visitor {
1453 boolean specialized;
1454 SpecialTreeVisitor() {
1455 this.specialized = false;
1456 }
1457
1458 @Override
1459 public void visitTree(JCTree tree) { /* no-op */ }
1460
1461 @Override
1462 public void visitVarDef(JCVariableDecl tree) {
1463 if ((tree.mods.flags & ENUM) != 0) {
1464 if (tree.init instanceof JCNewClass newClass && newClass.def != null) {
1465 specialized = true;
1466 }
1467 }
1468 }
1469 }
1470
1471 SpecialTreeVisitor sts = new SpecialTreeVisitor();
1472 JCClassDecl cdef = (JCClassDecl) tree;
1473 for (JCTree defs: cdef.defs) {
1474 defs.accept(sts);
1475 if (sts.specialized) return allowSealed ? SEALED : 0;
1476 }
1477 return FINAL;
1478 }
1479
1480 /* *************************************************************************
1481 * Type Validation
1482 **************************************************************************/
1483
1484 /** Validate a type expression. That is,
1485 * check that all type arguments of a parametric type are within
1486 * their bounds. This must be done in a second phase after type attribution
1487 * since a class might have a subclass as type parameter bound. E.g:
1488 *
1489 * <pre>{@code
1490 * class B<A extends C> { ... }
1491 * class C extends B<C> { ... }
1492 * }</pre>
1493 *
1494 * and we can't make sure that the bound is already attributed because
1495 * of possible cycles.
1496 *
1497 * Visitor method: Validate a type expression, if it is not null, catching
1498 * and reporting any completion failures.
1499 */
1500 void validate(JCTree tree, Env<AttrContext> env) {
1501 validate(tree, env, true);
1502 }
1503 void validate(JCTree tree, Env<AttrContext> env, boolean checkRaw) {
1504 new Validator(env).validateTree(tree, checkRaw, true);
1505 }
1506
1507 /** Visitor method: Validate a list of type expressions.
1508 */
1509 void validate(List<? extends JCTree> trees, Env<AttrContext> env) {
1510 for (List<? extends JCTree> l = trees; l.nonEmpty(); l = l.tail)
1511 validate(l.head, env);
1512 }
1513
1514 /** A visitor class for type validation.
1515 */
1516 class Validator extends JCTree.Visitor {
1517
1518 boolean checkRaw;
1519 boolean isOuter;
1520 Env<AttrContext> env;
1521
1522 Validator(Env<AttrContext> env) {
1523 this.env = env;
1524 }
1525
1526 @Override
1527 public void visitTypeArray(JCArrayTypeTree tree) {
1528 validateTree(tree.elemtype, checkRaw, isOuter);
1529 }
1530
1531 @Override
1532 public void visitTypeApply(JCTypeApply tree) {
1533 if (tree.type.hasTag(CLASS)) {
1534 List<JCExpression> args = tree.arguments;
1535 List<Type> forms = tree.type.tsym.type.getTypeArguments();
1536
1537 Type incompatibleArg = firstIncompatibleTypeArg(tree.type);
1538 if (incompatibleArg != null) {
1539 for (JCTree arg : tree.arguments) {
1540 if (arg.type == incompatibleArg) {
1541 log.error(arg, Errors.NotWithinBounds(incompatibleArg, forms.head));
1542 }
1543 forms = forms.tail;
1544 }
1545 }
1546
1547 forms = tree.type.tsym.type.getTypeArguments();
1548
1549 boolean is_java_lang_Class = tree.type.tsym.flatName() == names.java_lang_Class;
1550
1551 // For matching pairs of actual argument types `a' and
1552 // formal type parameters with declared bound `b' ...
1553 while (args.nonEmpty() && forms.nonEmpty()) {
1554 validateTree(args.head,
1555 !(isOuter && is_java_lang_Class),
1556 false);
1557 args = args.tail;
1558 forms = forms.tail;
1559 }
1560
1561 // Check that this type is either fully parameterized, or
1562 // not parameterized at all.
1563 if (tree.type.getEnclosingType().isRaw())
1564 log.error(tree.pos(), Errors.ImproperlyFormedTypeInnerRawParam);
1565 if (tree.clazz.hasTag(SELECT))
1566 visitSelectInternal((JCFieldAccess)tree.clazz);
1567 }
1568 }
1569
1570 @Override
1571 public void visitTypeParameter(JCTypeParameter tree) {
1572 validateTrees(tree.bounds, true, isOuter);
1573 checkClassBounds(tree.pos(), tree.type);
1574 }
1575
1576 @Override
1577 public void visitWildcard(JCWildcard tree) {
1578 if (tree.inner != null)
1579 validateTree(tree.inner, true, isOuter);
1580 }
1581
1582 @Override
1583 public void visitSelect(JCFieldAccess tree) {
1584 if (tree.type.hasTag(CLASS)) {
1585 visitSelectInternal(tree);
1586
1587 // Check that this type is either fully parameterized, or
1588 // not parameterized at all.
1589 if (tree.selected.type.isParameterized() && tree.type.tsym.type.getTypeArguments().nonEmpty())
1590 log.error(tree.pos(), Errors.ImproperlyFormedTypeParamMissing);
1591 }
1592 }
1593
1594 public void visitSelectInternal(JCFieldAccess tree) {
1595 if (tree.type.tsym.isStatic() &&
1596 tree.selected.type.isParameterized()) {
1597 // The enclosing type is not a class, so we are
1598 // looking at a static member type. However, the
1599 // qualifying expression is parameterized.
1600 log.error(tree.pos(), Errors.CantSelectStaticClassFromParamType);
1601 } else {
1602 // otherwise validate the rest of the expression
1603 tree.selected.accept(this);
1604 }
1605 }
1606
1607 @Override
1608 public void visitAnnotatedType(JCAnnotatedType tree) {
1609 tree.underlyingType.accept(this);
1610 }
1611
1612 @Override
1613 public void visitTypeIdent(JCPrimitiveTypeTree that) {
1614 if (that.type.hasTag(TypeTag.VOID)) {
1615 log.error(that.pos(), Errors.VoidNotAllowedHere);
1616 }
1617 super.visitTypeIdent(that);
1618 }
1619
1620 /** Default visitor method: do nothing.
1621 */
1622 @Override
1623 public void visitTree(JCTree tree) {
1624 }
1625
1626 public void validateTree(JCTree tree, boolean checkRaw, boolean isOuter) {
1627 if (tree != null) {
1628 boolean prevCheckRaw = this.checkRaw;
1629 this.checkRaw = checkRaw;
1630 this.isOuter = isOuter;
1631
1632 try {
1633 tree.accept(this);
1634 if (checkRaw)
1635 checkRaw(tree, env);
1636 } catch (CompletionFailure ex) {
1637 completionError(tree.pos(), ex);
1638 } finally {
1639 this.checkRaw = prevCheckRaw;
1640 }
1641 }
1642 }
1643
1644 public void validateTrees(List<? extends JCTree> trees, boolean checkRaw, boolean isOuter) {
1645 for (List<? extends JCTree> l = trees; l.nonEmpty(); l = l.tail)
1646 validateTree(l.head, checkRaw, isOuter);
1647 }
1648 }
1649
1650 void checkRaw(JCTree tree, Env<AttrContext> env) {
1651 if (lint.isEnabled(LintCategory.RAW) &&
1652 tree.type.hasTag(CLASS) &&
1653 !TreeInfo.isDiamond(tree) &&
1654 !withinAnonConstr(env) &&
1655 tree.type.isRaw()) {
1656 log.warning(LintCategory.RAW,
1657 tree.pos(), Warnings.RawClassUse(tree.type, tree.type.tsym.type));
1658 }
1659 }
1660 //where
1661 private boolean withinAnonConstr(Env<AttrContext> env) {
1662 return env.enclClass.name.isEmpty() &&
1663 env.enclMethod != null && env.enclMethod.name == names.init;
1664 }
1665
1666 /* *************************************************************************
1667 * Exception checking
1668 **************************************************************************/
1669
1670 /* The following methods treat classes as sets that contain
1671 * the class itself and all their subclasses
1672 */
1673
1674 /** Is given type a subtype of some of the types in given list?
1675 */
1676 boolean subset(Type t, List<Type> ts) {
1677 for (List<Type> l = ts; l.nonEmpty(); l = l.tail)
1678 if (types.isSubtype(t, l.head)) return true;
1679 return false;
1680 }
1681
1682 /** Is given type a subtype or supertype of
1683 * some of the types in given list?
1684 */
1685 boolean intersects(Type t, List<Type> ts) {
1686 for (List<Type> l = ts; l.nonEmpty(); l = l.tail)
1687 if (types.isSubtype(t, l.head) || types.isSubtype(l.head, t)) return true;
1688 return false;
1689 }
1690
1691 /** Add type set to given type list, unless it is a subclass of some class
1692 * in the list.
1693 */
1694 List<Type> incl(Type t, List<Type> ts) {
1695 return subset(t, ts) ? ts : excl(t, ts).prepend(t);
1696 }
1697
1698 /** Remove type set from type set list.
1699 */
1700 List<Type> excl(Type t, List<Type> ts) {
1701 if (ts.isEmpty()) {
1702 return ts;
1703 } else {
1704 List<Type> ts1 = excl(t, ts.tail);
1705 if (types.isSubtype(ts.head, t)) return ts1;
1706 else if (ts1 == ts.tail) return ts;
1707 else return ts1.prepend(ts.head);
1708 }
1709 }
1710
1711 /** Form the union of two type set lists.
1712 */
1713 List<Type> union(List<Type> ts1, List<Type> ts2) {
1714 List<Type> ts = ts1;
1715 for (List<Type> l = ts2; l.nonEmpty(); l = l.tail)
1716 ts = incl(l.head, ts);
1717 return ts;
1718 }
1719
1720 /** Form the difference of two type lists.
1721 */
1722 List<Type> diff(List<Type> ts1, List<Type> ts2) {
1723 List<Type> ts = ts1;
1724 for (List<Type> l = ts2; l.nonEmpty(); l = l.tail)
1725 ts = excl(l.head, ts);
1726 return ts;
1727 }
1728
1729 /** Form the intersection of two type lists.
1730 */
1731 public List<Type> intersect(List<Type> ts1, List<Type> ts2) {
1732 List<Type> ts = List.nil();
1733 for (List<Type> l = ts1; l.nonEmpty(); l = l.tail)
1734 if (subset(l.head, ts2)) ts = incl(l.head, ts);
1735 for (List<Type> l = ts2; l.nonEmpty(); l = l.tail)
1736 if (subset(l.head, ts1)) ts = incl(l.head, ts);
1737 return ts;
1738 }
1739
1740 /** Is exc an exception symbol that need not be declared?
1741 */
1742 boolean isUnchecked(ClassSymbol exc) {
1743 return
1744 exc.kind == ERR ||
1745 exc.isSubClass(syms.errorType.tsym, types) ||
1746 exc.isSubClass(syms.runtimeExceptionType.tsym, types);
1747 }
1748
1749 /** Is exc an exception type that need not be declared?
1750 */
1751 boolean isUnchecked(Type exc) {
1752 return
1753 (exc.hasTag(TYPEVAR)) ? isUnchecked(types.supertype(exc)) :
1754 (exc.hasTag(CLASS)) ? isUnchecked((ClassSymbol)exc.tsym) :
1755 exc.hasTag(BOT);
1756 }
1757
1758 boolean isChecked(Type exc) {
1759 return !isUnchecked(exc);
1760 }
1761
1762 /** Same, but handling completion failures.
1763 */
1764 boolean isUnchecked(DiagnosticPosition pos, Type exc) {
1765 try {
1766 return isUnchecked(exc);
1767 } catch (CompletionFailure ex) {
1768 completionError(pos, ex);
1769 return true;
1770 }
1771 }
1772
1773 /** Is exc handled by given exception list?
1774 */
1775 boolean isHandled(Type exc, List<Type> handled) {
1776 return isUnchecked(exc) || subset(exc, handled);
1777 }
1778
1779 /** Return all exceptions in thrown list that are not in handled list.
1780 * @param thrown The list of thrown exceptions.
1781 * @param handled The list of handled exceptions.
1782 */
1783 List<Type> unhandled(List<Type> thrown, List<Type> handled) {
1784 List<Type> unhandled = List.nil();
1785 for (List<Type> l = thrown; l.nonEmpty(); l = l.tail)
1786 if (!isHandled(l.head, handled)) unhandled = unhandled.prepend(l.head);
1787 return unhandled;
1788 }
1789
1790 /* *************************************************************************
1791 * Overriding/Implementation checking
1792 **************************************************************************/
1793
1794 /** The level of access protection given by a flag set,
1795 * where PRIVATE is highest and PUBLIC is lowest.
1796 */
1797 static int protection(long flags) {
1798 switch ((short)(flags & AccessFlags)) {
1799 case PRIVATE: return 3;
1800 case PROTECTED: return 1;
1801 default:
1802 case PUBLIC: return 0;
1803 case 0: return 2;
1804 }
1805 }
1806
1807 /** A customized "cannot override" error message.
1808 * @param m The overriding method.
1809 * @param other The overridden method.
1810 * @return An internationalized string.
1811 */
1812 Fragment cannotOverride(MethodSymbol m, MethodSymbol other) {
1813 Symbol mloc = m.location();
1814 Symbol oloc = other.location();
1815
1816 if ((other.owner.flags() & INTERFACE) == 0)
1817 return Fragments.CantOverride(m, mloc, other, oloc);
1818 else if ((m.owner.flags() & INTERFACE) == 0)
1819 return Fragments.CantImplement(m, mloc, other, oloc);
1820 else
1821 return Fragments.ClashesWith(m, mloc, other, oloc);
1822 }
1823
1824 /** A customized "override" warning message.
1825 * @param m The overriding method.
1826 * @param other The overridden method.
1827 * @return An internationalized string.
1828 */
1829 Fragment uncheckedOverrides(MethodSymbol m, MethodSymbol other) {
1830 Symbol mloc = m.location();
1831 Symbol oloc = other.location();
1832
1833 if ((other.owner.flags() & INTERFACE) == 0)
1834 return Fragments.UncheckedOverride(m, mloc, other, oloc);
1835 else if ((m.owner.flags() & INTERFACE) == 0)
1836 return Fragments.UncheckedImplement(m, mloc, other, oloc);
1837 else
1838 return Fragments.UncheckedClashWith(m, mloc, other, oloc);
1839 }
1840
1841 /** A customized "override" warning message.
1842 * @param m The overriding method.
1843 * @param other The overridden method.
1844 * @return An internationalized string.
1845 */
1846 Fragment varargsOverrides(MethodSymbol m, MethodSymbol other) {
1847 Symbol mloc = m.location();
1848 Symbol oloc = other.location();
1849
1850 if ((other.owner.flags() & INTERFACE) == 0)
1851 return Fragments.VarargsOverride(m, mloc, other, oloc);
1852 else if ((m.owner.flags() & INTERFACE) == 0)
1853 return Fragments.VarargsImplement(m, mloc, other, oloc);
1854 else
1855 return Fragments.VarargsClashWith(m, mloc, other, oloc);
1856 }
1857
1858 /** Check that this method conforms with overridden method 'other'.
1859 * where `origin' is the class where checking started.
1860 * Complications:
1861 * (1) Do not check overriding of synthetic methods
1862 * (reason: they might be final).
1863 * todo: check whether this is still necessary.
1864 * (2) Admit the case where an interface proxy throws fewer exceptions
1865 * than the method it implements. Augment the proxy methods with the
1866 * undeclared exceptions in this case.
1867 * (3) When generics are enabled, admit the case where an interface proxy
1868 * has a result type
1869 * extended by the result type of the method it implements.
1870 * Change the proxies result type to the smaller type in this case.
1871 *
1872 * @param tree The tree from which positions
1873 * are extracted for errors.
1874 * @param m The overriding method.
1875 * @param other The overridden method.
1876 * @param origin The class of which the overriding method
1877 * is a member.
1878 */
1879 void checkOverride(JCTree tree,
1880 MethodSymbol m,
1881 MethodSymbol other,
1882 ClassSymbol origin) {
1883 // Don't check overriding of synthetic methods or by bridge methods.
1884 if ((m.flags() & (SYNTHETIC|BRIDGE)) != 0 || (other.flags() & SYNTHETIC) != 0) {
1885 return;
1886 }
1887
1888 // Error if static method overrides instance method (JLS 8.4.8.2).
1889 if ((m.flags() & STATIC) != 0 &&
1890 (other.flags() & STATIC) == 0) {
1891 log.error(TreeInfo.diagnosticPositionFor(m, tree),
1892 Errors.OverrideStatic(cannotOverride(m, other)));
1893 m.flags_field |= BAD_OVERRIDE;
1894 return;
1895 }
1896
1897 // Error if instance method overrides static or final
1898 // method (JLS 8.4.8.1).
1899 if ((other.flags() & FINAL) != 0 ||
1900 (m.flags() & STATIC) == 0 &&
1901 (other.flags() & STATIC) != 0) {
1902 log.error(TreeInfo.diagnosticPositionFor(m, tree),
1903 Errors.OverrideMeth(cannotOverride(m, other),
1904 asFlagSet(other.flags() & (FINAL | STATIC))));
1905 m.flags_field |= BAD_OVERRIDE;
1906 return;
1907 }
1908
1909 if ((m.owner.flags() & ANNOTATION) != 0) {
1910 // handled in validateAnnotationMethod
1911 return;
1912 }
1913
1914 // Error if overriding method has weaker access (JLS 8.4.8.3).
1915 if (protection(m.flags()) > protection(other.flags())) {
1916 log.error(TreeInfo.diagnosticPositionFor(m, tree),
1917 (other.flags() & AccessFlags) == 0 ?
1918 Errors.OverrideWeakerAccess(cannotOverride(m, other),
1919 "package") :
1920 Errors.OverrideWeakerAccess(cannotOverride(m, other),
1921 asFlagSet(other.flags() & AccessFlags)));
1922 m.flags_field |= BAD_OVERRIDE;
1923 return;
1924 }
1925
1926 if (shouldCheckPreview(m, other, origin)) {
1927 checkPreview(tree.pos(), m, other);
1928 }
1929
1930 Type mt = types.memberType(origin.type, m);
1931 Type ot = types.memberType(origin.type, other);
1932 // Error if overriding result type is different
1933 // (or, in the case of generics mode, not a subtype) of
1934 // overridden result type. We have to rename any type parameters
1935 // before comparing types.
1936 List<Type> mtvars = mt.getTypeArguments();
1937 List<Type> otvars = ot.getTypeArguments();
1938 Type mtres = mt.getReturnType();
1939 Type otres = types.subst(ot.getReturnType(), otvars, mtvars);
1940
1941 overrideWarner.clear();
1942 boolean resultTypesOK =
1943 types.returnTypeSubstitutable(mt, ot, otres, overrideWarner);
1944 if (!resultTypesOK) {
1945 if ((m.flags() & STATIC) != 0 && (other.flags() & STATIC) != 0) {
1946 log.error(TreeInfo.diagnosticPositionFor(m, tree),
1947 Errors.OverrideIncompatibleRet(Fragments.CantHide(m, m.location(), other,
1948 other.location()), mtres, otres));
1949 m.flags_field |= BAD_OVERRIDE;
1950 } else {
1951 log.error(TreeInfo.diagnosticPositionFor(m, tree),
1952 Errors.OverrideIncompatibleRet(cannotOverride(m, other), mtres, otres));
1953 m.flags_field |= BAD_OVERRIDE;
1954 }
1955 return;
1956 } else if (overrideWarner.hasNonSilentLint(LintCategory.UNCHECKED)) {
1957 warnUnchecked(TreeInfo.diagnosticPositionFor(m, tree),
1958 Warnings.OverrideUncheckedRet(uncheckedOverrides(m, other), mtres, otres));
1959 }
1960
1961 // Error if overriding method throws an exception not reported
1962 // by overridden method.
1963 List<Type> otthrown = types.subst(ot.getThrownTypes(), otvars, mtvars);
1964 List<Type> unhandledErased = unhandled(mt.getThrownTypes(), types.erasure(otthrown));
1965 List<Type> unhandledUnerased = unhandled(mt.getThrownTypes(), otthrown);
1966 if (unhandledErased.nonEmpty()) {
1967 log.error(TreeInfo.diagnosticPositionFor(m, tree),
1968 Errors.OverrideMethDoesntThrow(cannotOverride(m, other), unhandledUnerased.head));
1969 m.flags_field |= BAD_OVERRIDE;
1970 return;
1971 }
1972 else if (unhandledUnerased.nonEmpty()) {
1973 warnUnchecked(TreeInfo.diagnosticPositionFor(m, tree),
1974 Warnings.OverrideUncheckedThrown(cannotOverride(m, other), unhandledUnerased.head));
1975 return;
1976 }
1977
1978 // Optional warning if varargs don't agree
1979 if ((((m.flags() ^ other.flags()) & Flags.VARARGS) != 0)
1980 && lint.isEnabled(LintCategory.OVERRIDES)) {
1981 log.warning(TreeInfo.diagnosticPositionFor(m, tree),
1982 ((m.flags() & Flags.VARARGS) != 0)
1983 ? Warnings.OverrideVarargsMissing(varargsOverrides(m, other))
1984 : Warnings.OverrideVarargsExtra(varargsOverrides(m, other)));
1985 }
1986
1987 // Warn if instance method overrides bridge method (compiler spec ??)
1988 if ((other.flags() & BRIDGE) != 0) {
1989 log.warning(TreeInfo.diagnosticPositionFor(m, tree),
1990 Warnings.OverrideBridge(uncheckedOverrides(m, other)));
1991 }
1992
1993 // Warn if a deprecated method overridden by a non-deprecated one.
1994 if (!isDeprecatedOverrideIgnorable(other, origin)) {
1995 Lint prevLint = setLint(lint.augment(m));
1996 try {
1997 checkDeprecated(() -> TreeInfo.diagnosticPositionFor(m, tree), m, other);
1998 } finally {
1999 setLint(prevLint);
2000 }
2001 }
2002 }
2003 // where
2004 private boolean shouldCheckPreview(MethodSymbol m, MethodSymbol other, ClassSymbol origin) {
2005 if (m.owner != origin ||
2006 //performance - only do the expensive checks when the overridden method is a Preview API:
2007 (other.flags() & PREVIEW_API) == 0) {
2008 return false;
2009 }
2010
2011 for (Symbol s : types.membersClosure(origin.type, false).getSymbolsByName(m.name)) {
2012 if (m != s && m.overrides(s, origin, types, false)) {
2013 //only produce preview warnings or errors if "m" immediatelly overrides "other"
2014 //without intermediate overriding methods:
2015 return s == other;
2016 }
2017 }
2018
2019 return false;
2020 }
2021 private boolean isDeprecatedOverrideIgnorable(MethodSymbol m, ClassSymbol origin) {
2022 // If the method, m, is defined in an interface, then ignore the issue if the method
2023 // is only inherited via a supertype and also implemented in the supertype,
2024 // because in that case, we will rediscover the issue when examining the method
2025 // in the supertype.
2026 // If the method, m, is not defined in an interface, then the only time we need to
2027 // address the issue is when the method is the supertype implementation: any other
2028 // case, we will have dealt with when examining the supertype classes
2029 ClassSymbol mc = m.enclClass();
2030 Type st = types.supertype(origin.type);
2031 if (!st.hasTag(CLASS))
2032 return true;
2033 MethodSymbol stimpl = m.implementation((ClassSymbol)st.tsym, types, false);
2034
2035 if (mc != null && ((mc.flags() & INTERFACE) != 0)) {
2036 List<Type> intfs = types.interfaces(origin.type);
2037 return (intfs.contains(mc.type) ? false : (stimpl != null));
2038 }
2039 else
2040 return (stimpl != m);
2041 }
2042
2043
2044 // used to check if there were any unchecked conversions
2045 Warner overrideWarner = new Warner();
2046
2047 /** Check that a class does not inherit two concrete methods
2048 * with the same signature.
2049 * @param pos Position to be used for error reporting.
2050 * @param site The class type to be checked.
2051 */
2052 public void checkCompatibleConcretes(DiagnosticPosition pos, Type site) {
2053 Type sup = types.supertype(site);
2054 if (!sup.hasTag(CLASS)) return;
2055
2056 for (Type t1 = sup;
2057 t1.hasTag(CLASS) && t1.tsym.type.isParameterized();
2058 t1 = types.supertype(t1)) {
2059 for (Symbol s1 : t1.tsym.members().getSymbols(NON_RECURSIVE)) {
2060 if (s1.kind != MTH ||
2061 (s1.flags() & (STATIC|SYNTHETIC|BRIDGE)) != 0 ||
2062 !s1.isInheritedIn(site.tsym, types) ||
2063 ((MethodSymbol)s1).implementation(site.tsym,
2064 types,
2065 true) != s1)
2066 continue;
2067 Type st1 = types.memberType(t1, s1);
2068 int s1ArgsLength = st1.getParameterTypes().length();
2069 if (st1 == s1.type) continue;
2070
2071 for (Type t2 = sup;
2072 t2.hasTag(CLASS);
2073 t2 = types.supertype(t2)) {
2074 for (Symbol s2 : t2.tsym.members().getSymbolsByName(s1.name)) {
2075 if (s2 == s1 ||
2076 s2.kind != MTH ||
2077 (s2.flags() & (STATIC|SYNTHETIC|BRIDGE)) != 0 ||
2078 s2.type.getParameterTypes().length() != s1ArgsLength ||
2079 !s2.isInheritedIn(site.tsym, types) ||
2080 ((MethodSymbol)s2).implementation(site.tsym,
2081 types,
2082 true) != s2)
2083 continue;
2084 Type st2 = types.memberType(t2, s2);
2085 if (types.overrideEquivalent(st1, st2))
2086 log.error(pos,
2087 Errors.ConcreteInheritanceConflict(s1, t1, s2, t2, sup));
2088 }
2089 }
2090 }
2091 }
2092 }
2093
2094 /** Check that classes (or interfaces) do not each define an abstract
2095 * method with same name and arguments but incompatible return types.
2096 * @param pos Position to be used for error reporting.
2097 * @param t1 The first argument type.
2098 * @param t2 The second argument type.
2099 */
2100 public boolean checkCompatibleAbstracts(DiagnosticPosition pos,
2101 Type t1,
2102 Type t2,
2103 Type site) {
2104 if ((site.tsym.flags() & COMPOUND) != 0) {
2105 // special case for intersections: need to eliminate wildcards in supertypes
2106 t1 = types.capture(t1);
2107 t2 = types.capture(t2);
2108 }
2109 return firstIncompatibility(pos, t1, t2, site) == null;
2110 }
2111
2112 /** Return the first method which is defined with same args
2113 * but different return types in two given interfaces, or null if none
2114 * exists.
2115 * @param t1 The first type.
2116 * @param t2 The second type.
2117 * @param site The most derived type.
2118 * @return symbol from t2 that conflicts with one in t1.
2119 */
2120 private Symbol firstIncompatibility(DiagnosticPosition pos, Type t1, Type t2, Type site) {
2121 Map<TypeSymbol,Type> interfaces1 = new HashMap<>();
2122 closure(t1, interfaces1);
2123 Map<TypeSymbol,Type> interfaces2;
2124 if (t1 == t2)
2125 interfaces2 = interfaces1;
2126 else
2127 closure(t2, interfaces1, interfaces2 = new HashMap<>());
2128
2129 for (Type t3 : interfaces1.values()) {
2130 for (Type t4 : interfaces2.values()) {
2131 Symbol s = firstDirectIncompatibility(pos, t3, t4, site);
2132 if (s != null) return s;
2133 }
2134 }
2135 return null;
2136 }
2137
2138 /** Compute all the supertypes of t, indexed by type symbol. */
2139 private void closure(Type t, Map<TypeSymbol,Type> typeMap) {
2140 if (!t.hasTag(CLASS)) return;
2141 if (typeMap.put(t.tsym, t) == null) {
2142 closure(types.supertype(t), typeMap);
2143 for (Type i : types.interfaces(t))
2144 closure(i, typeMap);
2145 }
2146 }
2147
2148 /** Compute all the supertypes of t, indexed by type symbol (except those in typesSkip). */
2149 private void closure(Type t, Map<TypeSymbol,Type> typesSkip, Map<TypeSymbol,Type> typeMap) {
2150 if (!t.hasTag(CLASS)) return;
2151 if (typesSkip.get(t.tsym) != null) return;
2152 if (typeMap.put(t.tsym, t) == null) {
2153 closure(types.supertype(t), typesSkip, typeMap);
2154 for (Type i : types.interfaces(t))
2155 closure(i, typesSkip, typeMap);
2156 }
2157 }
2158
2159 /** Return the first method in t2 that conflicts with a method from t1. */
2160 private Symbol firstDirectIncompatibility(DiagnosticPosition pos, Type t1, Type t2, Type site) {
2161 for (Symbol s1 : t1.tsym.members().getSymbols(NON_RECURSIVE)) {
2162 Type st1 = null;
2163 if (s1.kind != MTH || !s1.isInheritedIn(site.tsym, types) ||
2164 (s1.flags() & SYNTHETIC) != 0) continue;
2165 Symbol impl = ((MethodSymbol)s1).implementation(site.tsym, types, false);
2166 if (impl != null && (impl.flags() & ABSTRACT) == 0) continue;
2167 for (Symbol s2 : t2.tsym.members().getSymbolsByName(s1.name)) {
2168 if (s1 == s2) continue;
2169 if (s2.kind != MTH || !s2.isInheritedIn(site.tsym, types) ||
2170 (s2.flags() & SYNTHETIC) != 0) continue;
2171 if (st1 == null) st1 = types.memberType(t1, s1);
2172 Type st2 = types.memberType(t2, s2);
2173 if (types.overrideEquivalent(st1, st2)) {
2174 List<Type> tvars1 = st1.getTypeArguments();
2175 List<Type> tvars2 = st2.getTypeArguments();
2176 Type rt1 = st1.getReturnType();
2177 Type rt2 = types.subst(st2.getReturnType(), tvars2, tvars1);
2178 boolean compat =
2179 types.isSameType(rt1, rt2) ||
2180 !rt1.isPrimitiveOrVoid() &&
2181 !rt2.isPrimitiveOrVoid() &&
2182 (types.covariantReturnType(rt1, rt2, types.noWarnings) ||
2183 types.covariantReturnType(rt2, rt1, types.noWarnings)) ||
2184 checkCommonOverriderIn(s1,s2,site);
2185 if (!compat) {
2186 if (types.isSameType(t1, t2)) {
2187 log.error(pos, Errors.IncompatibleDiffRetSameType(t1,
2188 s2.name, types.memberType(t2, s2).getParameterTypes()));
2189 } else {
2190 log.error(pos, Errors.TypesIncompatible(t1, t2,
2191 Fragments.IncompatibleDiffRet(s2.name, types.memberType(t2, s2).getParameterTypes())));
2192 }
2193 return s2;
2194 }
2195 } else if (checkNameClash((ClassSymbol)site.tsym, s1, s2) &&
2196 !checkCommonOverriderIn(s1, s2, site)) {
2197 log.error(pos, Errors.NameClashSameErasureNoOverride(
2198 s1.name, types.memberType(site, s1).asMethodType().getParameterTypes(), s1.location(),
2199 s2.name, types.memberType(site, s2).asMethodType().getParameterTypes(), s2.location()));
2200 return s2;
2201 }
2202 }
2203 }
2204 return null;
2205 }
2206 //WHERE
2207 boolean checkCommonOverriderIn(Symbol s1, Symbol s2, Type site) {
2208 Map<TypeSymbol,Type> supertypes = new HashMap<>();
2209 Type st1 = types.memberType(site, s1);
2210 Type st2 = types.memberType(site, s2);
2211 closure(site, supertypes);
2212 for (Type t : supertypes.values()) {
2213 for (Symbol s3 : t.tsym.members().getSymbolsByName(s1.name)) {
2214 if (s3 == s1 || s3 == s2 || s3.kind != MTH || (s3.flags() & (BRIDGE|SYNTHETIC)) != 0) continue;
2215 Type st3 = types.memberType(site,s3);
2216 if (types.overrideEquivalent(st3, st1) &&
2217 types.overrideEquivalent(st3, st2) &&
2218 types.returnTypeSubstitutable(st3, st1) &&
2219 types.returnTypeSubstitutable(st3, st2)) {
2220 return true;
2221 }
2222 }
2223 }
2224 return false;
2225 }
2226
2227 /** Check that a given method conforms with any method it overrides.
2228 * @param tree The tree from which positions are extracted
2229 * for errors.
2230 * @param m The overriding method.
2231 */
2232 void checkOverride(Env<AttrContext> env, JCMethodDecl tree, MethodSymbol m) {
2233 ClassSymbol origin = (ClassSymbol)m.owner;
2234 if ((origin.flags() & ENUM) != 0 && names.finalize.equals(m.name)) {
2235 if (m.overrides(syms.enumFinalFinalize, origin, types, false)) {
2236 log.error(tree.pos(), Errors.EnumNoFinalize);
2237 return;
2238 }
2239 }
2240 if (allowValueClasses && origin.isValueClass() && names.finalize.equals(m.name)) {
2241 if (m.overrides(syms.objectFinalize, origin, types, false)) {
2242 log.warning(tree.pos(), Warnings.ValueFinalize);
2243 }
2244 }
2245 if (allowRecords && origin.isRecord()) {
2246 // let's find out if this is a user defined accessor in which case the @Override annotation is acceptable
2247 Optional<? extends RecordComponent> recordComponent = origin.getRecordComponents().stream()
2248 .filter(rc -> rc.accessor == tree.sym && (rc.accessor.flags_field & GENERATED_MEMBER) == 0).findFirst();
2249 if (recordComponent.isPresent()) {
2250 return;
2251 }
2252 }
2253
2254 for (Type t = origin.type; t.hasTag(CLASS);
2255 t = types.supertype(t)) {
2256 if (t != origin.type) {
2257 checkOverride(tree, t, origin, m);
2258 }
2259 for (Type t2 : types.interfaces(t)) {
2260 checkOverride(tree, t2, origin, m);
2261 }
2262 }
2263
2264 final boolean explicitOverride = m.attribute(syms.overrideType.tsym) != null;
2265 // Check if this method must override a super method due to being annotated with @Override
2266 // or by virtue of being a member of a diamond inferred anonymous class. Latter case is to
2267 // be treated "as if as they were annotated" with @Override.
2268 boolean mustOverride = explicitOverride ||
2269 (env.info.isAnonymousDiamond && !m.isConstructor() && !m.isPrivate());
2270 if (mustOverride && !isOverrider(m)) {
2271 DiagnosticPosition pos = tree.pos();
2272 for (JCAnnotation a : tree.getModifiers().annotations) {
2273 if (a.annotationType.type.tsym == syms.overrideType.tsym) {
2274 pos = a.pos();
2275 break;
2276 }
2277 }
2278 log.error(pos,
2279 explicitOverride ? (m.isStatic() ? Errors.StaticMethodsCannotBeAnnotatedWithOverride : Errors.MethodDoesNotOverrideSuperclass) :
2280 Errors.AnonymousDiamondMethodDoesNotOverrideSuperclass(Fragments.DiamondAnonymousMethodsImplicitlyOverride));
2281 }
2282 }
2283
2284 void checkOverride(JCTree tree, Type site, ClassSymbol origin, MethodSymbol m) {
2285 TypeSymbol c = site.tsym;
2286 for (Symbol sym : c.members().getSymbolsByName(m.name)) {
2287 if (m.overrides(sym, origin, types, false)) {
2288 if ((sym.flags() & ABSTRACT) == 0) {
2289 checkOverride(tree, m, (MethodSymbol)sym, origin);
2290 }
2291 }
2292 }
2293 }
2294
2295 private Predicate<Symbol> equalsHasCodeFilter = s -> MethodSymbol.implementation_filter.test(s) &&
2296 (s.flags() & BAD_OVERRIDE) == 0;
2297
2298 public void checkClassOverrideEqualsAndHashIfNeeded(DiagnosticPosition pos,
2299 ClassSymbol someClass) {
2300 /* At present, annotations cannot possibly have a method that is override
2301 * equivalent with Object.equals(Object) but in any case the condition is
2302 * fine for completeness.
2303 */
2304 if (someClass == (ClassSymbol)syms.objectType.tsym ||
2305 someClass.isInterface() || someClass.isEnum() ||
2306 (someClass.flags() & ANNOTATION) != 0 ||
2307 (someClass.flags() & ABSTRACT) != 0) return;
2308 //anonymous inner classes implementing interfaces need especial treatment
2309 if (someClass.isAnonymous()) {
2310 List<Type> interfaces = types.interfaces(someClass.type);
2311 if (interfaces != null && !interfaces.isEmpty() &&
2312 interfaces.head.tsym == syms.comparatorType.tsym) return;
2313 }
2314 checkClassOverrideEqualsAndHash(pos, someClass);
2315 }
2316
2317 private void checkClassOverrideEqualsAndHash(DiagnosticPosition pos,
2318 ClassSymbol someClass) {
2319 if (lint.isEnabled(LintCategory.OVERRIDES)) {
2320 MethodSymbol equalsAtObject = (MethodSymbol)syms.objectType
2321 .tsym.members().findFirst(names.equals);
2322 MethodSymbol hashCodeAtObject = (MethodSymbol)syms.objectType
2323 .tsym.members().findFirst(names.hashCode);
2324 MethodSymbol equalsImpl = types.implementation(equalsAtObject,
2325 someClass, false, equalsHasCodeFilter);
2326 boolean overridesEquals = equalsImpl != null &&
2327 equalsImpl.owner == someClass;
2328 boolean overridesHashCode = types.implementation(hashCodeAtObject,
2329 someClass, false, equalsHasCodeFilter) != hashCodeAtObject;
2330
2331 if (overridesEquals && !overridesHashCode) {
2332 log.warning(LintCategory.OVERRIDES, pos,
2333 Warnings.OverrideEqualsButNotHashcode(someClass));
2334 }
2335 }
2336 }
2337
2338 public void checkHasMain(DiagnosticPosition pos, ClassSymbol c) {
2339 boolean found = false;
2340
2341 for (Symbol sym : c.members().getSymbolsByName(names.main)) {
2342 if (sym.kind == MTH && (sym.flags() & PRIVATE) == 0) {
2343 MethodSymbol meth = (MethodSymbol)sym;
2344 if (!types.isSameType(meth.getReturnType(), syms.voidType)) {
2345 continue;
2346 }
2347 if (meth.params.isEmpty()) {
2348 found = true;
2349 break;
2350 }
2351 if (meth.params.size() != 1) {
2352 continue;
2353 }
2354 if (!types.isSameType(meth.params.head.type, types.makeArrayType(syms.stringType))) {
2355 continue;
2356 }
2357
2358 found = true;
2359 break;
2360 }
2361 }
2362
2363 if (!found) {
2364 log.error(pos, Errors.ImplicitClassDoesNotHaveMainMethod);
2365 }
2366 }
2367
2368 public void checkModuleName (JCModuleDecl tree) {
2369 Name moduleName = tree.sym.name;
2370 Assert.checkNonNull(moduleName);
2371 if (lint.isEnabled(LintCategory.MODULE)) {
2372 JCExpression qualId = tree.qualId;
2373 while (qualId != null) {
2374 Name componentName;
2375 DiagnosticPosition pos;
2376 switch (qualId.getTag()) {
2377 case SELECT:
2378 JCFieldAccess selectNode = ((JCFieldAccess) qualId);
2379 componentName = selectNode.name;
2380 pos = selectNode.pos();
2381 qualId = selectNode.selected;
2382 break;
2383 case IDENT:
2384 componentName = ((JCIdent) qualId).name;
2385 pos = qualId.pos();
2386 qualId = null;
2387 break;
2388 default:
2389 throw new AssertionError("Unexpected qualified identifier: " + qualId.toString());
2390 }
2391 if (componentName != null) {
2392 String moduleNameComponentString = componentName.toString();
2393 int nameLength = moduleNameComponentString.length();
2394 if (nameLength > 0 && Character.isDigit(moduleNameComponentString.charAt(nameLength - 1))) {
2395 log.warning(Lint.LintCategory.MODULE, pos, Warnings.PoorChoiceForModuleName(componentName));
2396 }
2397 }
2398 }
2399 }
2400 }
2401
2402 private boolean checkNameClash(ClassSymbol origin, Symbol s1, Symbol s2) {
2403 ClashFilter cf = new ClashFilter(origin.type);
2404 return (cf.test(s1) &&
2405 cf.test(s2) &&
2406 types.hasSameArgs(s1.erasure(types), s2.erasure(types)));
2407 }
2408
2409
2410 /** Check that all abstract members of given class have definitions.
2411 * @param pos Position to be used for error reporting.
2412 * @param c The class.
2413 */
2414 void checkAllDefined(DiagnosticPosition pos, ClassSymbol c) {
2415 MethodSymbol undef = types.firstUnimplementedAbstract(c);
2416 if (undef != null) {
2417 MethodSymbol undef1 =
2418 new MethodSymbol(undef.flags(), undef.name,
2419 types.memberType(c.type, undef), undef.owner);
2420 log.error(pos,
2421 Errors.DoesNotOverrideAbstract(c, undef1, undef1.location()));
2422 }
2423 }
2424
2425 void checkNonCyclicDecl(JCClassDecl tree) {
2426 CycleChecker cc = new CycleChecker();
2427 cc.scan(tree);
2428 if (!cc.errorFound && !cc.partialCheck) {
2429 tree.sym.flags_field |= ACYCLIC;
2430 }
2431 }
2432
2433 class CycleChecker extends TreeScanner {
2434
2435 Set<Symbol> seenClasses = new HashSet<>();
2436 boolean errorFound = false;
2437 boolean partialCheck = false;
2438
2439 private void checkSymbol(DiagnosticPosition pos, Symbol sym) {
2440 if (sym != null && sym.kind == TYP) {
2441 Env<AttrContext> classEnv = enter.getEnv((TypeSymbol)sym);
2442 if (classEnv != null) {
2443 DiagnosticSource prevSource = log.currentSource();
2444 try {
2445 log.useSource(classEnv.toplevel.sourcefile);
2446 scan(classEnv.tree);
2447 }
2448 finally {
2449 log.useSource(prevSource.getFile());
2450 }
2451 } else if (sym.kind == TYP) {
2452 checkClass(pos, sym, List.nil());
2453 }
2454 } else if (sym == null || sym.kind != PCK) {
2455 //not completed yet
2456 partialCheck = true;
2457 }
2458 }
2459
2460 @Override
2461 public void visitSelect(JCFieldAccess tree) {
2462 super.visitSelect(tree);
2463 checkSymbol(tree.pos(), tree.sym);
2464 }
2465
2466 @Override
2467 public void visitIdent(JCIdent tree) {
2468 checkSymbol(tree.pos(), tree.sym);
2469 }
2470
2471 @Override
2472 public void visitTypeApply(JCTypeApply tree) {
2473 scan(tree.clazz);
2474 }
2475
2476 @Override
2477 public void visitTypeArray(JCArrayTypeTree tree) {
2478 scan(tree.elemtype);
2479 }
2480
2481 @Override
2482 public void visitClassDef(JCClassDecl tree) {
2483 List<JCTree> supertypes = List.nil();
2484 if (tree.getExtendsClause() != null) {
2485 supertypes = supertypes.prepend(tree.getExtendsClause());
2486 }
2487 if (tree.getImplementsClause() != null) {
2488 for (JCTree intf : tree.getImplementsClause()) {
2489 supertypes = supertypes.prepend(intf);
2490 }
2491 }
2492 checkClass(tree.pos(), tree.sym, supertypes);
2493 }
2494
2495 void checkClass(DiagnosticPosition pos, Symbol c, List<JCTree> supertypes) {
2496 if ((c.flags_field & ACYCLIC) != 0)
2497 return;
2498 if (seenClasses.contains(c)) {
2499 errorFound = true;
2500 noteCyclic(pos, (ClassSymbol)c);
2501 } else if (!c.type.isErroneous()) {
2502 try {
2503 seenClasses.add(c);
2504 if (c.type.hasTag(CLASS)) {
2505 if (supertypes.nonEmpty()) {
2506 scan(supertypes);
2507 }
2508 else {
2509 ClassType ct = (ClassType)c.type;
2510 if (ct.supertype_field == null ||
2511 ct.interfaces_field == null) {
2512 //not completed yet
2513 partialCheck = true;
2514 return;
2515 }
2516 checkSymbol(pos, ct.supertype_field.tsym);
2517 for (Type intf : ct.interfaces_field) {
2518 checkSymbol(pos, intf.tsym);
2519 }
2520 }
2521 if (c.owner.kind == TYP) {
2522 checkSymbol(pos, c.owner);
2523 }
2524 }
2525 } finally {
2526 seenClasses.remove(c);
2527 }
2528 }
2529 }
2530 }
2531
2532 /** Check for cyclic references. Issue an error if the
2533 * symbol of the type referred to has a LOCKED flag set.
2534 *
2535 * @param pos Position to be used for error reporting.
2536 * @param t The type referred to.
2537 */
2538 void checkNonCyclic(DiagnosticPosition pos, Type t) {
2539 checkNonCyclicInternal(pos, t);
2540 }
2541
2542
2543 void checkNonCyclic(DiagnosticPosition pos, TypeVar t) {
2544 checkNonCyclic1(pos, t, List.nil());
2545 }
2546
2547 private void checkNonCyclic1(DiagnosticPosition pos, Type t, List<TypeVar> seen) {
2548 final TypeVar tv;
2549 if (t.hasTag(TYPEVAR) && (t.tsym.flags() & UNATTRIBUTED) != 0)
2550 return;
2551 if (seen.contains(t)) {
2552 tv = (TypeVar)t;
2553 tv.setUpperBound(types.createErrorType(t));
2554 log.error(pos, Errors.CyclicInheritance(t));
2555 } else if (t.hasTag(TYPEVAR)) {
2556 tv = (TypeVar)t;
2557 seen = seen.prepend(tv);
2558 for (Type b : types.getBounds(tv))
2559 checkNonCyclic1(pos, b, seen);
2560 }
2561 }
2562
2563 /** Check for cyclic references. Issue an error if the
2564 * symbol of the type referred to has a LOCKED flag set.
2565 *
2566 * @param pos Position to be used for error reporting.
2567 * @param t The type referred to.
2568 * @return True if the check completed on all attributed classes
2569 */
2570 private boolean checkNonCyclicInternal(DiagnosticPosition pos, Type t) {
2571 boolean complete = true; // was the check complete?
2572 //- System.err.println("checkNonCyclicInternal("+t+");");//DEBUG
2573 Symbol c = t.tsym;
2574 if ((c.flags_field & ACYCLIC) != 0) return true;
2575
2576 if ((c.flags_field & LOCKED) != 0) {
2577 noteCyclic(pos, (ClassSymbol)c);
2578 } else if (!c.type.isErroneous()) {
2579 try {
2580 c.flags_field |= LOCKED;
2581 if (c.type.hasTag(CLASS)) {
2582 ClassType clazz = (ClassType)c.type;
2583 if (clazz.interfaces_field != null)
2584 for (List<Type> l=clazz.interfaces_field; l.nonEmpty(); l=l.tail)
2585 complete &= checkNonCyclicInternal(pos, l.head);
2586 if (clazz.supertype_field != null) {
2587 Type st = clazz.supertype_field;
2588 if (st != null && st.hasTag(CLASS))
2589 complete &= checkNonCyclicInternal(pos, st);
2590 }
2591 if (c.owner.kind == TYP)
2592 complete &= checkNonCyclicInternal(pos, c.owner.type);
2593 }
2594 } finally {
2595 c.flags_field &= ~LOCKED;
2596 }
2597 }
2598 if (complete)
2599 complete = ((c.flags_field & UNATTRIBUTED) == 0) && c.isCompleted();
2600 if (complete) c.flags_field |= ACYCLIC;
2601 return complete;
2602 }
2603
2604 /** Note that we found an inheritance cycle. */
2605 private void noteCyclic(DiagnosticPosition pos, ClassSymbol c) {
2606 log.error(pos, Errors.CyclicInheritance(c));
2607 for (List<Type> l=types.interfaces(c.type); l.nonEmpty(); l=l.tail)
2608 l.head = types.createErrorType((ClassSymbol)l.head.tsym, Type.noType);
2609 Type st = types.supertype(c.type);
2610 if (st.hasTag(CLASS))
2611 ((ClassType)c.type).supertype_field = types.createErrorType((ClassSymbol)st.tsym, Type.noType);
2612 c.type = types.createErrorType(c, c.type);
2613 c.flags_field |= ACYCLIC;
2614 }
2615
2616 /** Check that all methods which implement some
2617 * method conform to the method they implement.
2618 * @param tree The class definition whose members are checked.
2619 */
2620 void checkImplementations(JCClassDecl tree) {
2621 checkImplementations(tree, tree.sym, tree.sym);
2622 }
2623 //where
2624 /** Check that all methods which implement some
2625 * method in `ic' conform to the method they implement.
2626 */
2627 void checkImplementations(JCTree tree, ClassSymbol origin, ClassSymbol ic) {
2628 for (List<Type> l = types.closure(ic.type); l.nonEmpty(); l = l.tail) {
2629 ClassSymbol lc = (ClassSymbol)l.head.tsym;
2630 if ((lc.flags() & ABSTRACT) != 0) {
2631 for (Symbol sym : lc.members().getSymbols(NON_RECURSIVE)) {
2632 if (sym.kind == MTH &&
2633 (sym.flags() & (STATIC|ABSTRACT)) == ABSTRACT) {
2634 MethodSymbol absmeth = (MethodSymbol)sym;
2635 MethodSymbol implmeth = absmeth.implementation(origin, types, false);
2636 if (implmeth != null && implmeth != absmeth &&
2637 (implmeth.owner.flags() & INTERFACE) ==
2638 (origin.flags() & INTERFACE)) {
2639 // don't check if implmeth is in a class, yet
2640 // origin is an interface. This case arises only
2641 // if implmeth is declared in Object. The reason is
2642 // that interfaces really don't inherit from
2643 // Object it's just that the compiler represents
2644 // things that way.
2645 checkOverride(tree, implmeth, absmeth, origin);
2646 }
2647 }
2648 }
2649 }
2650 }
2651 }
2652
2653 /** Check that all abstract methods implemented by a class are
2654 * mutually compatible.
2655 * @param pos Position to be used for error reporting.
2656 * @param c The class whose interfaces are checked.
2657 */
2658 void checkCompatibleSupertypes(DiagnosticPosition pos, Type c) {
2659 List<Type> supertypes = types.interfaces(c);
2660 Type supertype = types.supertype(c);
2661 if (supertype.hasTag(CLASS) &&
2662 (supertype.tsym.flags() & ABSTRACT) != 0)
2663 supertypes = supertypes.prepend(supertype);
2664 for (List<Type> l = supertypes; l.nonEmpty(); l = l.tail) {
2665 if (!l.head.getTypeArguments().isEmpty() &&
2666 !checkCompatibleAbstracts(pos, l.head, l.head, c))
2667 return;
2668 for (List<Type> m = supertypes; m != l; m = m.tail)
2669 if (!checkCompatibleAbstracts(pos, l.head, m.head, c))
2670 return;
2671 }
2672 checkCompatibleConcretes(pos, c);
2673
2674 Type identitySuper = null;
2675 for (Type t : types.closure(c)) {
2676 if (t != c) {
2677 if (t.isIdentityClass() && (t.tsym.flags() & VALUE_BASED) == 0)
2678 identitySuper = t;
2679 if (c.isValueClass() && identitySuper != null && identitySuper.tsym != syms.objectType.tsym) { // Object is special
2680 log.error(pos, Errors.ValueTypeHasIdentitySuperType(c, identitySuper));
2681 break;
2682 }
2683 }
2684 }
2685 }
2686
2687 /** Check that all non-override equivalent methods accessible from 'site'
2688 * are mutually compatible (JLS 8.4.8/9.4.1).
2689 *
2690 * @param pos Position to be used for error reporting.
2691 * @param site The class whose methods are checked.
2692 * @param sym The method symbol to be checked.
2693 */
2694 void checkOverrideClashes(DiagnosticPosition pos, Type site, MethodSymbol sym) {
2695 ClashFilter cf = new ClashFilter(site);
2696 //for each method m1 that is overridden (directly or indirectly)
2697 //by method 'sym' in 'site'...
2698
2699 ArrayList<Symbol> symbolsByName = new ArrayList<>();
2700 types.membersClosure(site, false).getSymbolsByName(sym.name, cf).forEach(symbolsByName::add);
2701 for (Symbol m1 : symbolsByName) {
2702 if (!sym.overrides(m1, site.tsym, types, false)) {
2703 continue;
2704 }
2705
2706 //...check each method m2 that is a member of 'site'
2707 for (Symbol m2 : symbolsByName) {
2708 if (m2 == m1) continue;
2709 //if (i) the signature of 'sym' is not a subsignature of m1 (seen as
2710 //a member of 'site') and (ii) m1 has the same erasure as m2, issue an error
2711 if (!types.isSubSignature(sym.type, types.memberType(site, m2)) &&
2712 types.hasSameArgs(m2.erasure(types), m1.erasure(types))) {
2713 sym.flags_field |= CLASH;
2714 if (m1 == sym) {
2715 log.error(pos, Errors.NameClashSameErasureNoOverride(
2716 m1.name, types.memberType(site, m1).asMethodType().getParameterTypes(), m1.location(),
2717 m2.name, types.memberType(site, m2).asMethodType().getParameterTypes(), m2.location()));
2718 } else {
2719 ClassType ct = (ClassType)site;
2720 String kind = ct.isInterface() ? "interface" : "class";
2721 log.error(pos, Errors.NameClashSameErasureNoOverride1(
2722 kind,
2723 ct.tsym.name,
2724 m1.name,
2725 types.memberType(site, m1).asMethodType().getParameterTypes(),
2726 m1.location(),
2727 m2.name,
2728 types.memberType(site, m2).asMethodType().getParameterTypes(),
2729 m2.location()));
2730 }
2731 return;
2732 }
2733 }
2734 }
2735 }
2736
2737 /** Check that all static methods accessible from 'site' are
2738 * mutually compatible (JLS 8.4.8).
2739 *
2740 * @param pos Position to be used for error reporting.
2741 * @param site The class whose methods are checked.
2742 * @param sym The method symbol to be checked.
2743 */
2744 void checkHideClashes(DiagnosticPosition pos, Type site, MethodSymbol sym) {
2745 ClashFilter cf = new ClashFilter(site);
2746 //for each method m1 that is a member of 'site'...
2747 for (Symbol s : types.membersClosure(site, true).getSymbolsByName(sym.name, cf)) {
2748 //if (i) the signature of 'sym' is not a subsignature of m1 (seen as
2749 //a member of 'site') and (ii) 'sym' has the same erasure as m1, issue an error
2750 if (!types.isSubSignature(sym.type, types.memberType(site, s))) {
2751 if (types.hasSameArgs(s.erasure(types), sym.erasure(types))) {
2752 log.error(pos,
2753 Errors.NameClashSameErasureNoHide(sym, sym.location(), s, s.location()));
2754 return;
2755 }
2756 }
2757 }
2758 }
2759
2760 //where
2761 private class ClashFilter implements Predicate<Symbol> {
2762
2763 Type site;
2764
2765 ClashFilter(Type site) {
2766 this.site = site;
2767 }
2768
2769 boolean shouldSkip(Symbol s) {
2770 return (s.flags() & CLASH) != 0 &&
2771 s.owner == site.tsym;
2772 }
2773
2774 @Override
2775 public boolean test(Symbol s) {
2776 return s.kind == MTH &&
2777 (s.flags() & SYNTHETIC) == 0 &&
2778 !shouldSkip(s) &&
2779 s.isInheritedIn(site.tsym, types) &&
2780 !s.isConstructor();
2781 }
2782 }
2783
2784 void checkDefaultMethodClashes(DiagnosticPosition pos, Type site) {
2785 DefaultMethodClashFilter dcf = new DefaultMethodClashFilter(site);
2786 for (Symbol m : types.membersClosure(site, false).getSymbols(dcf)) {
2787 Assert.check(m.kind == MTH);
2788 List<MethodSymbol> prov = types.interfaceCandidates(site, (MethodSymbol)m);
2789 if (prov.size() > 1) {
2790 ListBuffer<Symbol> abstracts = new ListBuffer<>();
2791 ListBuffer<Symbol> defaults = new ListBuffer<>();
2792 for (MethodSymbol provSym : prov) {
2793 if ((provSym.flags() & DEFAULT) != 0) {
2794 defaults = defaults.append(provSym);
2795 } else if ((provSym.flags() & ABSTRACT) != 0) {
2796 abstracts = abstracts.append(provSym);
2797 }
2798 if (defaults.nonEmpty() && defaults.size() + abstracts.size() >= 2) {
2799 //strong semantics - issue an error if two sibling interfaces
2800 //have two override-equivalent defaults - or if one is abstract
2801 //and the other is default
2802 Fragment diagKey;
2803 Symbol s1 = defaults.first();
2804 Symbol s2;
2805 if (defaults.size() > 1) {
2806 s2 = defaults.toList().tail.head;
2807 diagKey = Fragments.IncompatibleUnrelatedDefaults(Kinds.kindName(site.tsym), site,
2808 m.name, types.memberType(site, m).getParameterTypes(),
2809 s1.location(), s2.location());
2810
2811 } else {
2812 s2 = abstracts.first();
2813 diagKey = Fragments.IncompatibleAbstractDefault(Kinds.kindName(site.tsym), site,
2814 m.name, types.memberType(site, m).getParameterTypes(),
2815 s1.location(), s2.location());
2816 }
2817 log.error(pos, Errors.TypesIncompatible(s1.location().type, s2.location().type, diagKey));
2818 break;
2819 }
2820 }
2821 }
2822 }
2823 }
2824
2825 //where
2826 private class DefaultMethodClashFilter implements Predicate<Symbol> {
2827
2828 Type site;
2829
2830 DefaultMethodClashFilter(Type site) {
2831 this.site = site;
2832 }
2833
2834 @Override
2835 public boolean test(Symbol s) {
2836 return s.kind == MTH &&
2837 (s.flags() & DEFAULT) != 0 &&
2838 s.isInheritedIn(site.tsym, types) &&
2839 !s.isConstructor();
2840 }
2841 }
2842
2843 /** Report warnings for potentially ambiguous method declarations in the given site. */
2844 void checkPotentiallyAmbiguousOverloads(JCClassDecl tree, Type site) {
2845
2846 // Skip if warning not enabled
2847 if (!lint.isEnabled(LintCategory.OVERLOADS))
2848 return;
2849
2850 // Gather all of site's methods, including overridden methods, grouped by name (except Object methods)
2851 List<java.util.List<MethodSymbol>> methodGroups = methodsGroupedByName(site,
2852 new PotentiallyAmbiguousFilter(site), ArrayList::new);
2853
2854 // Build the predicate that determines if site is responsible for an ambiguity
2855 BiPredicate<MethodSymbol, MethodSymbol> responsible = buildResponsiblePredicate(site, methodGroups);
2856
2857 // Now remove overridden methods from each group, leaving only site's actual members
2858 methodGroups.forEach(list -> removePreempted(list, (m1, m2) -> m1.overrides(m2, site.tsym, types, false)));
2859
2860 // Allow site's own declared methods (only) to apply @SuppressWarnings("overloads")
2861 methodGroups.forEach(list -> list.removeIf(
2862 m -> m.owner == site.tsym && !lint.augment(m).isEnabled(LintCategory.OVERLOADS)));
2863
2864 // Warn about ambiguous overload method pairs for which site is responsible
2865 methodGroups.forEach(list -> compareAndRemove(list, (m1, m2) -> {
2866
2867 // See if this is an ambiguous overload for which "site" is responsible
2868 if (!potentiallyAmbiguousOverload(site, m1, m2) || !responsible.test(m1, m2))
2869 return 0;
2870
2871 // Locate the warning at one of the methods, if possible
2872 DiagnosticPosition pos =
2873 m1.owner == site.tsym ? TreeInfo.diagnosticPositionFor(m1, tree) :
2874 m2.owner == site.tsym ? TreeInfo.diagnosticPositionFor(m2, tree) :
2875 tree.pos();
2876
2877 // Log the warning
2878 log.warning(LintCategory.OVERLOADS, pos,
2879 Warnings.PotentiallyAmbiguousOverload(
2880 m1.asMemberOf(site, types), m1.location(),
2881 m2.asMemberOf(site, types), m2.location()));
2882
2883 // Don't warn again for either of these two methods
2884 return FIRST | SECOND;
2885 }));
2886 }
2887
2888 /** Build a predicate that determines, given two methods that are members of the given class,
2889 * whether the class should be held "responsible" if the methods are potentially ambiguous.
2890 *
2891 * Sometimes ambiguous methods are unavoidable because they're inherited from a supertype.
2892 * For example, any subtype of Spliterator.OfInt will have ambiguities for both
2893 * forEachRemaining() and tryAdvance() (in both cases the overloads are IntConsumer and
2894 * Consumer<? super Integer>). So we only want to "blame" a class when that class is
2895 * itself responsible for creating the ambiguity. We declare that a class C is "responsible"
2896 * for the ambiguity between two methods m1 and m2 if there is no direct supertype T of C
2897 * such that m1 and m2, or some overrides thereof, both exist in T and are ambiguous in T.
2898 * As an optimization, we first check if either method is declared in C and does not override
2899 * any other methods; in this case the class is definitely responsible.
2900 */
2901 BiPredicate<MethodSymbol, MethodSymbol> buildResponsiblePredicate(Type site,
2902 List<? extends Collection<MethodSymbol>> methodGroups) {
2903
2904 // Define the "overrides" predicate
2905 BiPredicate<MethodSymbol, MethodSymbol> overrides = (m1, m2) -> m1.overrides(m2, site.tsym, types, false);
2906
2907 // Map each method declared in site to a list of the supertype method(s) it directly overrides
2908 HashMap<MethodSymbol, ArrayList<MethodSymbol>> overriddenMethodsMap = new HashMap<>();
2909 methodGroups.forEach(list -> {
2910 for (MethodSymbol m : list) {
2911
2912 // Skip methods not declared in site
2913 if (m.owner != site.tsym)
2914 continue;
2915
2916 // Gather all supertype methods overridden by m, directly or indirectly
2917 ArrayList<MethodSymbol> overriddenMethods = list.stream()
2918 .filter(m2 -> m2 != m && overrides.test(m, m2))
2919 .collect(Collectors.toCollection(ArrayList::new));
2920
2921 // Eliminate non-direct overrides
2922 removePreempted(overriddenMethods, overrides);
2923
2924 // Add to map
2925 overriddenMethodsMap.put(m, overriddenMethods);
2926 }
2927 });
2928
2929 // Build the predicate
2930 return (m1, m2) -> {
2931
2932 // Get corresponding supertype methods (if declared in site)
2933 java.util.List<MethodSymbol> overriddenMethods1 = overriddenMethodsMap.get(m1);
2934 java.util.List<MethodSymbol> overriddenMethods2 = overriddenMethodsMap.get(m2);
2935
2936 // Quick check for the case where a method was added by site itself
2937 if (overriddenMethods1 != null && overriddenMethods1.isEmpty())
2938 return true;
2939 if (overriddenMethods2 != null && overriddenMethods2.isEmpty())
2940 return true;
2941
2942 // Get each method's corresponding method(s) from supertypes of site
2943 java.util.List<MethodSymbol> supertypeMethods1 = overriddenMethods1 != null ?
2944 overriddenMethods1 : Collections.singletonList(m1);
2945 java.util.List<MethodSymbol> supertypeMethods2 = overriddenMethods2 != null ?
2946 overriddenMethods2 : Collections.singletonList(m2);
2947
2948 // See if we can blame some direct supertype instead
2949 return types.directSupertypes(site).stream()
2950 .filter(stype -> stype != syms.objectType)
2951 .map(stype -> stype.tsym.type) // view supertype in its original form
2952 .noneMatch(stype -> {
2953 for (MethodSymbol sm1 : supertypeMethods1) {
2954 if (!types.isSubtype(types.erasure(stype), types.erasure(sm1.owner.type)))
2955 continue;
2956 for (MethodSymbol sm2 : supertypeMethods2) {
2957 if (!types.isSubtype(types.erasure(stype), types.erasure(sm2.owner.type)))
2958 continue;
2959 if (potentiallyAmbiguousOverload(stype, sm1, sm2))
2960 return true;
2961 }
2962 }
2963 return false;
2964 });
2965 };
2966 }
2967
2968 /** Gather all of site's methods, including overridden methods, grouped and sorted by name,
2969 * after applying the given filter.
2970 */
2971 <C extends Collection<MethodSymbol>> List<C> methodsGroupedByName(Type site,
2972 Predicate<Symbol> filter, Supplier<? extends C> groupMaker) {
2973 Iterable<Symbol> symbols = types.membersClosure(site, false).getSymbols(filter, RECURSIVE);
2974 return StreamSupport.stream(symbols.spliterator(), false)
2975 .map(MethodSymbol.class::cast)
2976 .collect(Collectors.groupingBy(m -> m.name, Collectors.toCollection(groupMaker)))
2977 .entrySet()
2978 .stream()
2979 .sorted(Comparator.comparing(e -> e.getKey().toString()))
2980 .map(Map.Entry::getValue)
2981 .collect(List.collector());
2982 }
2983
2984 /** Compare elements in a list pair-wise in order to remove some of them.
2985 * @param list mutable list of items
2986 * @param comparer returns flag bit(s) to remove FIRST and/or SECOND
2987 */
2988 <T> void compareAndRemove(java.util.List<T> list, ToIntBiFunction<? super T, ? super T> comparer) {
2989 for (int index1 = 0; index1 < list.size() - 1; index1++) {
2990 T item1 = list.get(index1);
2991 for (int index2 = index1 + 1; index2 < list.size(); index2++) {
2992 T item2 = list.get(index2);
2993 int flags = comparer.applyAsInt(item1, item2);
2994 if ((flags & SECOND) != 0)
2995 list.remove(index2--); // remove item2
2996 if ((flags & FIRST) != 0) {
2997 list.remove(index1--); // remove item1
2998 break;
2999 }
3000 }
3001 }
3002 }
3003
3004 /** Remove elements in a list that are preempted by some other element in the list.
3005 * @param list mutable list of items
3006 * @param preempts decides if one item preempts another, causing the second one to be removed
3007 */
3008 <T> void removePreempted(java.util.List<T> list, BiPredicate<? super T, ? super T> preempts) {
3009 compareAndRemove(list, (item1, item2) -> {
3010 int flags = 0;
3011 if (preempts.test(item1, item2))
3012 flags |= SECOND;
3013 if (preempts.test(item2, item1))
3014 flags |= FIRST;
3015 return flags;
3016 });
3017 }
3018
3019 /** Filters method candidates for the "potentially ambiguous method" check */
3020 class PotentiallyAmbiguousFilter extends ClashFilter {
3021
3022 PotentiallyAmbiguousFilter(Type site) {
3023 super(site);
3024 }
3025
3026 @Override
3027 boolean shouldSkip(Symbol s) {
3028 return s.owner.type.tsym == syms.objectType.tsym || super.shouldSkip(s);
3029 }
3030 }
3031
3032 /**
3033 * Report warnings for potentially ambiguous method declarations. Two declarations
3034 * are potentially ambiguous if they feature two unrelated functional interface
3035 * in same argument position (in which case, a call site passing an implicit
3036 * lambda would be ambiguous). This assumes they already have the same name.
3037 */
3038 boolean potentiallyAmbiguousOverload(Type site, MethodSymbol msym1, MethodSymbol msym2) {
3039 Assert.check(msym1.name == msym2.name);
3040 if (msym1 == msym2)
3041 return false;
3042 Type mt1 = types.memberType(site, msym1);
3043 Type mt2 = types.memberType(site, msym2);
3044 //if both generic methods, adjust type variables
3045 if (mt1.hasTag(FORALL) && mt2.hasTag(FORALL) &&
3046 types.hasSameBounds((ForAll)mt1, (ForAll)mt2)) {
3047 mt2 = types.subst(mt2, ((ForAll)mt2).tvars, ((ForAll)mt1).tvars);
3048 }
3049 //expand varargs methods if needed
3050 int maxLength = Math.max(mt1.getParameterTypes().length(), mt2.getParameterTypes().length());
3051 List<Type> args1 = rs.adjustArgs(mt1.getParameterTypes(), msym1, maxLength, true);
3052 List<Type> args2 = rs.adjustArgs(mt2.getParameterTypes(), msym2, maxLength, true);
3053 //if arities don't match, exit
3054 if (args1.length() != args2.length())
3055 return false;
3056 boolean potentiallyAmbiguous = false;
3057 while (args1.nonEmpty() && args2.nonEmpty()) {
3058 Type s = args1.head;
3059 Type t = args2.head;
3060 if (!types.isSubtype(t, s) && !types.isSubtype(s, t)) {
3061 if (types.isFunctionalInterface(s) && types.isFunctionalInterface(t) &&
3062 types.findDescriptorType(s).getParameterTypes().length() > 0 &&
3063 types.findDescriptorType(s).getParameterTypes().length() ==
3064 types.findDescriptorType(t).getParameterTypes().length()) {
3065 potentiallyAmbiguous = true;
3066 } else {
3067 return false;
3068 }
3069 }
3070 args1 = args1.tail;
3071 args2 = args2.tail;
3072 }
3073 return potentiallyAmbiguous;
3074 }
3075
3076 void checkAccessFromSerializableElement(final JCTree tree, boolean isLambda) {
3077 if (warnOnAnyAccessToMembers ||
3078 (lint.isEnabled(LintCategory.SERIAL) &&
3079 !lint.isSuppressed(LintCategory.SERIAL) &&
3080 isLambda)) {
3081 Symbol sym = TreeInfo.symbol(tree);
3082 if (!sym.kind.matches(KindSelector.VAL_MTH)) {
3083 return;
3084 }
3085
3086 if (sym.kind == VAR) {
3087 if ((sym.flags() & PARAMETER) != 0 ||
3088 sym.isDirectlyOrIndirectlyLocal() ||
3089 sym.name == names._this ||
3090 sym.name == names._super) {
3091 return;
3092 }
3093 }
3094
3095 if (!types.isSubtype(sym.owner.type, syms.serializableType) &&
3096 isEffectivelyNonPublic(sym)) {
3097 if (isLambda) {
3098 if (belongsToRestrictedPackage(sym)) {
3099 log.warning(LintCategory.SERIAL, tree.pos(),
3100 Warnings.AccessToMemberFromSerializableLambda(sym));
3101 }
3102 } else {
3103 log.warning(tree.pos(),
3104 Warnings.AccessToMemberFromSerializableElement(sym));
3105 }
3106 }
3107 }
3108 }
3109
3110 private boolean isEffectivelyNonPublic(Symbol sym) {
3111 if (sym.packge() == syms.rootPackage) {
3112 return false;
3113 }
3114
3115 while (sym.kind != PCK) {
3116 if ((sym.flags() & PUBLIC) == 0) {
3117 return true;
3118 }
3119 sym = sym.owner;
3120 }
3121 return false;
3122 }
3123
3124 private boolean belongsToRestrictedPackage(Symbol sym) {
3125 String fullName = sym.packge().fullname.toString();
3126 return fullName.startsWith("java.") ||
3127 fullName.startsWith("javax.") ||
3128 fullName.startsWith("sun.") ||
3129 fullName.contains(".internal.");
3130 }
3131
3132 /** Check that class c does not implement directly or indirectly
3133 * the same parameterized interface with two different argument lists.
3134 * @param pos Position to be used for error reporting.
3135 * @param type The type whose interfaces are checked.
3136 */
3137 void checkClassBounds(DiagnosticPosition pos, Type type) {
3138 checkClassBounds(pos, new HashMap<TypeSymbol,Type>(), type);
3139 }
3140 //where
3141 /** Enter all interfaces of type `type' into the hash table `seensofar'
3142 * with their class symbol as key and their type as value. Make
3143 * sure no class is entered with two different types.
3144 */
3145 void checkClassBounds(DiagnosticPosition pos,
3146 Map<TypeSymbol,Type> seensofar,
3147 Type type) {
3148 if (type.isErroneous()) return;
3149 for (List<Type> l = types.interfaces(type); l.nonEmpty(); l = l.tail) {
3150 Type it = l.head;
3151 if (type.hasTag(CLASS) && !it.hasTag(CLASS)) continue; // JLS 8.1.5
3152
3153 Type oldit = seensofar.put(it.tsym, it);
3154 if (oldit != null) {
3155 List<Type> oldparams = oldit.allparams();
3156 List<Type> newparams = it.allparams();
3157 if (!types.containsTypeEquivalent(oldparams, newparams))
3158 log.error(pos,
3159 Errors.CantInheritDiffArg(it.tsym,
3160 Type.toString(oldparams),
3161 Type.toString(newparams)));
3162 }
3163 checkClassBounds(pos, seensofar, it);
3164 }
3165 Type st = types.supertype(type);
3166 if (type.hasTag(CLASS) && !st.hasTag(CLASS)) return; // JLS 8.1.4
3167 if (st != Type.noType) checkClassBounds(pos, seensofar, st);
3168 }
3169
3170 /** Enter interface into into set.
3171 * If it existed already, issue a "repeated interface" error.
3172 */
3173 void checkNotRepeated(DiagnosticPosition pos, Type it, Set<Symbol> its) {
3174 if (its.contains(it.tsym))
3175 log.error(pos, Errors.RepeatedInterface);
3176 else {
3177 its.add(it.tsym);
3178 }
3179 }
3180
3181 /* *************************************************************************
3182 * Check annotations
3183 **************************************************************************/
3184
3185 /**
3186 * Recursively validate annotations values
3187 */
3188 void validateAnnotationTree(JCTree tree) {
3189 class AnnotationValidator extends TreeScanner {
3190 @Override
3191 public void visitAnnotation(JCAnnotation tree) {
3192 if (!tree.type.isErroneous() && tree.type.tsym.isAnnotationType()) {
3193 super.visitAnnotation(tree);
3194 validateAnnotation(tree);
3195 }
3196 }
3197 }
3198 tree.accept(new AnnotationValidator());
3199 }
3200
3201 /**
3202 * {@literal
3203 * Annotation types are restricted to primitives, String, an
3204 * enum, an annotation, Class, Class<?>, Class<? extends
3205 * Anything>, arrays of the preceding.
3206 * }
3207 */
3208 void validateAnnotationType(JCTree restype) {
3209 // restype may be null if an error occurred, so don't bother validating it
3210 if (restype != null) {
3211 validateAnnotationType(restype.pos(), restype.type);
3212 }
3213 }
3214
3215 void validateAnnotationType(DiagnosticPosition pos, Type type) {
3216 if (type.isPrimitive()) return;
3217 if (types.isSameType(type, syms.stringType)) return;
3218 if ((type.tsym.flags() & Flags.ENUM) != 0) return;
3219 if ((type.tsym.flags() & Flags.ANNOTATION) != 0) return;
3220 if (types.cvarLowerBound(type).tsym == syms.classType.tsym) return;
3221 if (types.isArray(type) && !types.isArray(types.elemtype(type))) {
3222 validateAnnotationType(pos, types.elemtype(type));
3223 return;
3224 }
3225 log.error(pos, Errors.InvalidAnnotationMemberType);
3226 }
3227
3228 /**
3229 * "It is also a compile-time error if any method declared in an
3230 * annotation type has a signature that is override-equivalent to
3231 * that of any public or protected method declared in class Object
3232 * or in the interface annotation.Annotation."
3233 *
3234 * @jls 9.6 Annotation Types
3235 */
3236 void validateAnnotationMethod(DiagnosticPosition pos, MethodSymbol m) {
3237 for (Type sup = syms.annotationType; sup.hasTag(CLASS); sup = types.supertype(sup)) {
3238 Scope s = sup.tsym.members();
3239 for (Symbol sym : s.getSymbolsByName(m.name)) {
3240 if (sym.kind == MTH &&
3241 (sym.flags() & (PUBLIC | PROTECTED)) != 0 &&
3242 types.overrideEquivalent(m.type, sym.type))
3243 log.error(pos, Errors.IntfAnnotationMemberClash(sym, sup));
3244 }
3245 }
3246 }
3247
3248 /** Check the annotations of a symbol.
3249 */
3250 public void validateAnnotations(List<JCAnnotation> annotations, JCTree declarationTree, Symbol s) {
3251 for (JCAnnotation a : annotations)
3252 validateAnnotation(a, declarationTree, s);
3253 }
3254
3255 /** Check the type annotations.
3256 */
3257 public void validateTypeAnnotations(List<JCAnnotation> annotations, Symbol s, boolean isTypeParameter) {
3258 for (JCAnnotation a : annotations)
3259 validateTypeAnnotation(a, s, isTypeParameter);
3260 }
3261
3262 /** Check an annotation of a symbol.
3263 */
3264 private void validateAnnotation(JCAnnotation a, JCTree declarationTree, Symbol s) {
3265 /** NOTE: if annotation processors are present, annotation processing rounds can happen after this method,
3266 * this can impact in particular records for which annotations are forcibly propagated.
3267 */
3268 validateAnnotationTree(a);
3269 boolean isRecordMember = ((s.flags_field & RECORD) != 0 || s.enclClass() != null && s.enclClass().isRecord());
3270
3271 boolean isRecordField = (s.flags_field & RECORD) != 0 &&
3272 declarationTree.hasTag(VARDEF) &&
3273 s.owner.kind == TYP;
3274
3275 if (isRecordField) {
3276 // first we need to check if the annotation is applicable to records
3277 Name[] targets = getTargetNames(a);
3278 boolean appliesToRecords = false;
3279 for (Name target : targets) {
3280 appliesToRecords =
3281 target == names.FIELD ||
3282 target == names.PARAMETER ||
3283 target == names.METHOD ||
3284 target == names.TYPE_USE ||
3285 target == names.RECORD_COMPONENT;
3286 if (appliesToRecords) {
3287 break;
3288 }
3289 }
3290 if (!appliesToRecords) {
3291 log.error(a.pos(), Errors.AnnotationTypeNotApplicable);
3292 } else {
3293 /* lets now find the annotations in the field that are targeted to record components and append them to
3294 * the corresponding record component
3295 */
3296 ClassSymbol recordClass = (ClassSymbol) s.owner;
3297 RecordComponent rc = recordClass.getRecordComponent((VarSymbol)s);
3298 SymbolMetadata metadata = rc.getMetadata();
3299 if (metadata == null || metadata.isEmpty()) {
3300 /* if not is empty then we have already been here, which is the case if multiple annotations are applied
3301 * to the record component declaration
3302 */
3303 rc.appendAttributes(s.getRawAttributes().stream().filter(anno ->
3304 Arrays.stream(getTargetNames(anno.type.tsym)).anyMatch(name -> name == names.RECORD_COMPONENT)
3305 ).collect(List.collector()));
3306
3307 JCVariableDecl fieldAST = (JCVariableDecl) declarationTree;
3308 for (JCAnnotation fieldAnnot : fieldAST.mods.annotations) {
3309 for (JCAnnotation rcAnnot : rc.declarationFor().mods.annotations) {
3310 if (rcAnnot.pos == fieldAnnot.pos) {
3311 rcAnnot.setType(fieldAnnot.type);
3312 break;
3313 }
3314 }
3315 }
3316
3317 /* At this point, we used to carry over any type annotations from the VARDEF to the record component, but
3318 * that is problematic, since we get here only when *some* annotation is applied to the SE5 (declaration)
3319 * annotation location, inadvertently failing to carry over the type annotations when the VarDef has no
3320 * annotations in the SE5 annotation location.
3321 *
3322 * Now type annotations are assigned to record components in a method that would execute irrespective of
3323 * whether there are SE5 annotations on a VarDef viz com.sun.tools.javac.code.TypeAnnotations.TypeAnnotationPositions.visitVarDef
3324 */
3325 }
3326 }
3327 }
3328
3329 /* the section below is tricky. Annotations applied to record components are propagated to the corresponding
3330 * record member so if an annotation has target: FIELD, it is propagated to the corresponding FIELD, if it has
3331 * target METHOD, it is propagated to the accessor and so on. But at the moment when method members are generated
3332 * there is no enough information to propagate only the right annotations. So all the annotations are propagated
3333 * to all the possible locations.
3334 *
3335 * At this point we need to remove all the annotations that are not in place before going on with the annotation
3336 * party. On top of the above there is the issue that there is no AST representing record components, just symbols
3337 * so the corresponding field has been holding all the annotations and it's metadata has been modified as if it
3338 * was both a field and a record component.
3339 *
3340 * So there are two places where we need to trim annotations from: the metadata of the symbol and / or the modifiers
3341 * in the AST. Whatever is in the metadata will be written to the class file, whatever is in the modifiers could
3342 * be see by annotation processors.
3343 *
3344 * The metadata contains both type annotations and declaration annotations. At this point of the game we don't
3345 * need to care about type annotations, they are all in the right place. But we could need to remove declaration
3346 * annotations. So for declaration annotations if they are not applicable to the record member, excluding type
3347 * annotations which are already correct, then we will remove it. For the AST modifiers if the annotation is not
3348 * applicable either as type annotation and or declaration annotation, only in that case it will be removed.
3349 *
3350 * So it could be that annotation is removed as a declaration annotation but it is kept in the AST modifier for
3351 * further inspection by annotation processors.
3352 *
3353 * For example:
3354 *
3355 * import java.lang.annotation.*;
3356 *
3357 * @Target({ElementType.TYPE_USE, ElementType.RECORD_COMPONENT})
3358 * @Retention(RetentionPolicy.RUNTIME)
3359 * @interface Anno { }
3360 *
3361 * record R(@Anno String s) {}
3362 *
3363 * at this point we will have for the case of the generated field:
3364 * - @Anno in the modifier
3365 * - @Anno as a type annotation
3366 * - @Anno as a declaration annotation
3367 *
3368 * the last one should be removed because the annotation has not FIELD as target but it was applied as a
3369 * declaration annotation because the field was being treated both as a field and as a record component
3370 * as we have already copied the annotations to the record component, now the field doesn't need to hold
3371 * annotations that are not intended for it anymore. Still @Anno has to be kept in the AST's modifiers as it
3372 * is applicable as a type annotation to the type of the field.
3373 */
3374
3375 if (a.type.tsym.isAnnotationType()) {
3376 Optional<Set<Name>> applicableTargetsOp = getApplicableTargets(a, s);
3377 if (!applicableTargetsOp.isEmpty()) {
3378 Set<Name> applicableTargets = applicableTargetsOp.get();
3379 boolean notApplicableOrIsTypeUseOnly = applicableTargets.isEmpty() ||
3380 applicableTargets.size() == 1 && applicableTargets.contains(names.TYPE_USE);
3381 boolean isCompGeneratedRecordElement = isRecordMember && (s.flags_field & Flags.GENERATED_MEMBER) != 0;
3382 boolean isCompRecordElementWithNonApplicableDeclAnno = isCompGeneratedRecordElement && notApplicableOrIsTypeUseOnly;
3383
3384 if (applicableTargets.isEmpty() || isCompRecordElementWithNonApplicableDeclAnno) {
3385 if (isCompRecordElementWithNonApplicableDeclAnno) {
3386 /* so we have found an annotation that is not applicable to a record member that was generated by the
3387 * compiler. This was intentionally done at TypeEnter, now is the moment strip away the annotations
3388 * that are not applicable to the given record member
3389 */
3390 JCModifiers modifiers = TreeInfo.getModifiers(declarationTree);
3391 /* lets first remove the annotation from the modifier if it is not applicable, we have to check again as
3392 * it could be a type annotation
3393 */
3394 if (modifiers != null && applicableTargets.isEmpty()) {
3395 ListBuffer<JCAnnotation> newAnnotations = new ListBuffer<>();
3396 for (JCAnnotation anno : modifiers.annotations) {
3397 if (anno != a) {
3398 newAnnotations.add(anno);
3399 }
3400 }
3401 modifiers.annotations = newAnnotations.toList();
3402 }
3403 // now lets remove it from the symbol
3404 s.getMetadata().removeDeclarationMetadata(a.attribute);
3405 } else {
3406 log.error(a.pos(), Errors.AnnotationTypeNotApplicable);
3407 }
3408 }
3409 /* if we are seeing the @SafeVarargs annotation applied to a compiler generated accessor,
3410 * then this is an error as we know that no compiler generated accessor will be a varargs
3411 * method, better to fail asap
3412 */
3413 if (isCompGeneratedRecordElement && !isRecordField && a.type.tsym == syms.trustMeType.tsym && declarationTree.hasTag(METHODDEF)) {
3414 log.error(a.pos(), Errors.VarargsInvalidTrustmeAnno(syms.trustMeType.tsym, Fragments.VarargsTrustmeOnNonVarargsAccessor(s)));
3415 }
3416 }
3417 }
3418
3419 if (a.annotationType.type.tsym == syms.functionalInterfaceType.tsym) {
3420 if (s.kind != TYP) {
3421 log.error(a.pos(), Errors.BadFunctionalIntfAnno);
3422 } else if (!s.isInterface() || (s.flags() & ANNOTATION) != 0) {
3423 log.error(a.pos(), Errors.BadFunctionalIntfAnno1(Fragments.NotAFunctionalIntf(s)));
3424 }
3425 }
3426 }
3427
3428 public void validateTypeAnnotation(JCAnnotation a, Symbol s, boolean isTypeParameter) {
3429 Assert.checkNonNull(a.type);
3430 // we just want to validate that the anotation doesn't have any wrong target
3431 if (s != null) getApplicableTargets(a, s);
3432 validateAnnotationTree(a);
3433
3434 if (a.hasTag(TYPE_ANNOTATION) &&
3435 !a.annotationType.type.isErroneous() &&
3436 !isTypeAnnotation(a, isTypeParameter)) {
3437 log.error(a.pos(), Errors.AnnotationTypeNotApplicableToType(a.type));
3438 }
3439 }
3440
3441 /**
3442 * Validate the proposed container 'repeatable' on the
3443 * annotation type symbol 's'. Report errors at position
3444 * 'pos'.
3445 *
3446 * @param s The (annotation)type declaration annotated with a @Repeatable
3447 * @param repeatable the @Repeatable on 's'
3448 * @param pos where to report errors
3449 */
3450 public void validateRepeatable(TypeSymbol s, Attribute.Compound repeatable, DiagnosticPosition pos) {
3451 Assert.check(types.isSameType(repeatable.type, syms.repeatableType));
3452
3453 Type t = null;
3454 List<Pair<MethodSymbol,Attribute>> l = repeatable.values;
3455 if (!l.isEmpty()) {
3456 Assert.check(l.head.fst.name == names.value);
3457 if (l.head.snd instanceof Attribute.Class) {
3458 t = ((Attribute.Class)l.head.snd).getValue();
3459 }
3460 }
3461
3462 if (t == null) {
3463 // errors should already have been reported during Annotate
3464 return;
3465 }
3466
3467 validateValue(t.tsym, s, pos);
3468 validateRetention(t.tsym, s, pos);
3469 validateDocumented(t.tsym, s, pos);
3470 validateInherited(t.tsym, s, pos);
3471 validateTarget(t.tsym, s, pos);
3472 validateDefault(t.tsym, pos);
3473 }
3474
3475 private void validateValue(TypeSymbol container, TypeSymbol contained, DiagnosticPosition pos) {
3476 Symbol sym = container.members().findFirst(names.value);
3477 if (sym != null && sym.kind == MTH) {
3478 MethodSymbol m = (MethodSymbol) sym;
3479 Type ret = m.getReturnType();
3480 if (!(ret.hasTag(ARRAY) && types.isSameType(((ArrayType)ret).elemtype, contained.type))) {
3481 log.error(pos,
3482 Errors.InvalidRepeatableAnnotationValueReturn(container,
3483 ret,
3484 types.makeArrayType(contained.type)));
3485 }
3486 } else {
3487 log.error(pos, Errors.InvalidRepeatableAnnotationNoValue(container));
3488 }
3489 }
3490
3491 private void validateRetention(TypeSymbol container, TypeSymbol contained, DiagnosticPosition pos) {
3492 Attribute.RetentionPolicy containerRetention = types.getRetention(container);
3493 Attribute.RetentionPolicy containedRetention = types.getRetention(contained);
3494
3495 boolean error = false;
3496 switch (containedRetention) {
3497 case RUNTIME:
3498 if (containerRetention != Attribute.RetentionPolicy.RUNTIME) {
3499 error = true;
3500 }
3501 break;
3502 case CLASS:
3503 if (containerRetention == Attribute.RetentionPolicy.SOURCE) {
3504 error = true;
3505 }
3506 }
3507 if (error ) {
3508 log.error(pos,
3509 Errors.InvalidRepeatableAnnotationRetention(container,
3510 containerRetention.name(),
3511 contained,
3512 containedRetention.name()));
3513 }
3514 }
3515
3516 private void validateDocumented(Symbol container, Symbol contained, DiagnosticPosition pos) {
3517 if (contained.attribute(syms.documentedType.tsym) != null) {
3518 if (container.attribute(syms.documentedType.tsym) == null) {
3519 log.error(pos, Errors.InvalidRepeatableAnnotationNotDocumented(container, contained));
3520 }
3521 }
3522 }
3523
3524 private void validateInherited(Symbol container, Symbol contained, DiagnosticPosition pos) {
3525 if (contained.attribute(syms.inheritedType.tsym) != null) {
3526 if (container.attribute(syms.inheritedType.tsym) == null) {
3527 log.error(pos, Errors.InvalidRepeatableAnnotationNotInherited(container, contained));
3528 }
3529 }
3530 }
3531
3532 private void validateTarget(TypeSymbol container, TypeSymbol contained, DiagnosticPosition pos) {
3533 // The set of targets the container is applicable to must be a subset
3534 // (with respect to annotation target semantics) of the set of targets
3535 // the contained is applicable to. The target sets may be implicit or
3536 // explicit.
3537
3538 Set<Name> containerTargets;
3539 Attribute.Array containerTarget = getAttributeTargetAttribute(container);
3540 if (containerTarget == null) {
3541 containerTargets = getDefaultTargetSet();
3542 } else {
3543 containerTargets = new HashSet<>();
3544 for (Attribute app : containerTarget.values) {
3545 if (!(app instanceof Attribute.Enum attributeEnum)) {
3546 continue; // recovery
3547 }
3548 containerTargets.add(attributeEnum.value.name);
3549 }
3550 }
3551
3552 Set<Name> containedTargets;
3553 Attribute.Array containedTarget = getAttributeTargetAttribute(contained);
3554 if (containedTarget == null) {
3555 containedTargets = getDefaultTargetSet();
3556 } else {
3557 containedTargets = new HashSet<>();
3558 for (Attribute app : containedTarget.values) {
3559 if (!(app instanceof Attribute.Enum attributeEnum)) {
3560 continue; // recovery
3561 }
3562 containedTargets.add(attributeEnum.value.name);
3563 }
3564 }
3565
3566 if (!isTargetSubsetOf(containerTargets, containedTargets)) {
3567 log.error(pos, Errors.InvalidRepeatableAnnotationIncompatibleTarget(container, contained));
3568 }
3569 }
3570
3571 /* get a set of names for the default target */
3572 private Set<Name> getDefaultTargetSet() {
3573 if (defaultTargets == null) {
3574 defaultTargets = Set.of(defaultTargetMetaInfo());
3575 }
3576
3577 return defaultTargets;
3578 }
3579 private Set<Name> defaultTargets;
3580
3581
3582 /** Checks that s is a subset of t, with respect to ElementType
3583 * semantics, specifically {ANNOTATION_TYPE} is a subset of {TYPE},
3584 * and {TYPE_USE} covers the set {ANNOTATION_TYPE, TYPE, TYPE_USE,
3585 * TYPE_PARAMETER}.
3586 */
3587 private boolean isTargetSubsetOf(Set<Name> s, Set<Name> t) {
3588 // Check that all elements in s are present in t
3589 for (Name n2 : s) {
3590 boolean currentElementOk = false;
3591 for (Name n1 : t) {
3592 if (n1 == n2) {
3593 currentElementOk = true;
3594 break;
3595 } else if (n1 == names.TYPE && n2 == names.ANNOTATION_TYPE) {
3596 currentElementOk = true;
3597 break;
3598 } else if (n1 == names.TYPE_USE &&
3599 (n2 == names.TYPE ||
3600 n2 == names.ANNOTATION_TYPE ||
3601 n2 == names.TYPE_PARAMETER)) {
3602 currentElementOk = true;
3603 break;
3604 }
3605 }
3606 if (!currentElementOk)
3607 return false;
3608 }
3609 return true;
3610 }
3611
3612 private void validateDefault(Symbol container, DiagnosticPosition pos) {
3613 // validate that all other elements of containing type has defaults
3614 Scope scope = container.members();
3615 for(Symbol elm : scope.getSymbols()) {
3616 if (elm.name != names.value &&
3617 elm.kind == MTH &&
3618 ((MethodSymbol)elm).defaultValue == null) {
3619 log.error(pos,
3620 Errors.InvalidRepeatableAnnotationElemNondefault(container, elm));
3621 }
3622 }
3623 }
3624
3625 /** Is s a method symbol that overrides a method in a superclass? */
3626 boolean isOverrider(Symbol s) {
3627 if (s.kind != MTH || s.isStatic())
3628 return false;
3629 MethodSymbol m = (MethodSymbol)s;
3630 TypeSymbol owner = (TypeSymbol)m.owner;
3631 for (Type sup : types.closure(owner.type)) {
3632 if (sup == owner.type)
3633 continue; // skip "this"
3634 Scope scope = sup.tsym.members();
3635 for (Symbol sym : scope.getSymbolsByName(m.name)) {
3636 if (!sym.isStatic() && m.overrides(sym, owner, types, true))
3637 return true;
3638 }
3639 }
3640 return false;
3641 }
3642
3643 /** Is the annotation applicable to types? */
3644 protected boolean isTypeAnnotation(JCAnnotation a, boolean isTypeParameter) {
3645 List<Attribute> targets = typeAnnotations.annotationTargets(a.annotationType.type.tsym);
3646 return (targets == null) ?
3647 (Feature.NO_TARGET_ANNOTATION_APPLICABILITY.allowedInSource(source) && isTypeParameter) :
3648 targets.stream()
3649 .anyMatch(attr -> isTypeAnnotation(attr, isTypeParameter));
3650 }
3651 //where
3652 boolean isTypeAnnotation(Attribute a, boolean isTypeParameter) {
3653 Attribute.Enum e = (Attribute.Enum)a;
3654 return (e.value.name == names.TYPE_USE ||
3655 (isTypeParameter && e.value.name == names.TYPE_PARAMETER));
3656 }
3657
3658 /** Is the annotation applicable to the symbol? */
3659 Name[] getTargetNames(JCAnnotation a) {
3660 return getTargetNames(a.annotationType.type.tsym);
3661 }
3662
3663 public Name[] getTargetNames(TypeSymbol annoSym) {
3664 Attribute.Array arr = getAttributeTargetAttribute(annoSym);
3665 Name[] targets;
3666 if (arr == null) {
3667 targets = defaultTargetMetaInfo();
3668 } else {
3669 // TODO: can we optimize this?
3670 targets = new Name[arr.values.length];
3671 for (int i=0; i<arr.values.length; ++i) {
3672 Attribute app = arr.values[i];
3673 if (!(app instanceof Attribute.Enum attributeEnum)) {
3674 return new Name[0];
3675 }
3676 targets[i] = attributeEnum.value.name;
3677 }
3678 }
3679 return targets;
3680 }
3681
3682 boolean annotationApplicable(JCAnnotation a, Symbol s) {
3683 Optional<Set<Name>> targets = getApplicableTargets(a, s);
3684 /* the optional could be empty if the annotation is unknown in that case
3685 * we return that it is applicable and if it is erroneous that should imply
3686 * an error at the declaration site
3687 */
3688 return targets.isEmpty() || targets.isPresent() && !targets.get().isEmpty();
3689 }
3690
3691 Optional<Set<Name>> getApplicableTargets(JCAnnotation a, Symbol s) {
3692 Attribute.Array arr = getAttributeTargetAttribute(a.annotationType.type.tsym);
3693 Name[] targets;
3694 Set<Name> applicableTargets = new HashSet<>();
3695
3696 if (arr == null) {
3697 targets = defaultTargetMetaInfo();
3698 } else {
3699 // TODO: can we optimize this?
3700 targets = new Name[arr.values.length];
3701 for (int i=0; i<arr.values.length; ++i) {
3702 Attribute app = arr.values[i];
3703 if (!(app instanceof Attribute.Enum attributeEnum)) {
3704 // recovery
3705 return Optional.empty();
3706 }
3707 targets[i] = attributeEnum.value.name;
3708 }
3709 }
3710 for (Name target : targets) {
3711 if (target == names.TYPE) {
3712 if (s.kind == TYP)
3713 applicableTargets.add(names.TYPE);
3714 } else if (target == names.FIELD) {
3715 if (s.kind == VAR && s.owner.kind != MTH)
3716 applicableTargets.add(names.FIELD);
3717 } else if (target == names.RECORD_COMPONENT) {
3718 if (s.getKind() == ElementKind.RECORD_COMPONENT) {
3719 applicableTargets.add(names.RECORD_COMPONENT);
3720 }
3721 } else if (target == names.METHOD) {
3722 if (s.kind == MTH && !s.isConstructor())
3723 applicableTargets.add(names.METHOD);
3724 } else if (target == names.PARAMETER) {
3725 if (s.kind == VAR &&
3726 (s.owner.kind == MTH && (s.flags() & PARAMETER) != 0)) {
3727 applicableTargets.add(names.PARAMETER);
3728 }
3729 } else if (target == names.CONSTRUCTOR) {
3730 if (s.kind == MTH && s.isConstructor())
3731 applicableTargets.add(names.CONSTRUCTOR);
3732 } else if (target == names.LOCAL_VARIABLE) {
3733 if (s.kind == VAR && s.owner.kind == MTH &&
3734 (s.flags() & PARAMETER) == 0) {
3735 applicableTargets.add(names.LOCAL_VARIABLE);
3736 }
3737 } else if (target == names.ANNOTATION_TYPE) {
3738 if (s.kind == TYP && (s.flags() & ANNOTATION) != 0) {
3739 applicableTargets.add(names.ANNOTATION_TYPE);
3740 }
3741 } else if (target == names.PACKAGE) {
3742 if (s.kind == PCK)
3743 applicableTargets.add(names.PACKAGE);
3744 } else if (target == names.TYPE_USE) {
3745 if (s.kind == VAR && s.owner.kind == MTH && s.type.hasTag(NONE)) {
3746 //cannot type annotate implicitly typed locals
3747 continue;
3748 } else if (s.kind == TYP || s.kind == VAR ||
3749 (s.kind == MTH && !s.isConstructor() &&
3750 !s.type.getReturnType().hasTag(VOID)) ||
3751 (s.kind == MTH && s.isConstructor())) {
3752 applicableTargets.add(names.TYPE_USE);
3753 }
3754 } else if (target == names.TYPE_PARAMETER) {
3755 if (s.kind == TYP && s.type.hasTag(TYPEVAR))
3756 applicableTargets.add(names.TYPE_PARAMETER);
3757 } else if (target == names.MODULE) {
3758 if (s.kind == MDL)
3759 applicableTargets.add(names.MODULE);
3760 } else {
3761 log.error(a, Errors.AnnotationUnrecognizedAttributeName(a.type, target));
3762 return Optional.empty(); // Unknown ElementType
3763 }
3764 }
3765 return Optional.of(applicableTargets);
3766 }
3767
3768 Attribute.Array getAttributeTargetAttribute(TypeSymbol s) {
3769 Attribute.Compound atTarget = s.getAnnotationTypeMetadata().getTarget();
3770 if (atTarget == null) return null; // ok, is applicable
3771 Attribute atValue = atTarget.member(names.value);
3772 return (atValue instanceof Attribute.Array attributeArray) ? attributeArray : null;
3773 }
3774
3775 private Name[] dfltTargetMeta;
3776 private Name[] defaultTargetMetaInfo() {
3777 if (dfltTargetMeta == null) {
3778 ArrayList<Name> defaultTargets = new ArrayList<>();
3779 defaultTargets.add(names.PACKAGE);
3780 defaultTargets.add(names.TYPE);
3781 defaultTargets.add(names.FIELD);
3782 defaultTargets.add(names.METHOD);
3783 defaultTargets.add(names.CONSTRUCTOR);
3784 defaultTargets.add(names.ANNOTATION_TYPE);
3785 defaultTargets.add(names.LOCAL_VARIABLE);
3786 defaultTargets.add(names.PARAMETER);
3787 if (allowRecords) {
3788 defaultTargets.add(names.RECORD_COMPONENT);
3789 }
3790 if (allowModules) {
3791 defaultTargets.add(names.MODULE);
3792 }
3793 dfltTargetMeta = defaultTargets.toArray(new Name[0]);
3794 }
3795 return dfltTargetMeta;
3796 }
3797
3798 /** Check an annotation value.
3799 *
3800 * @param a The annotation tree to check
3801 * @return true if this annotation tree is valid, otherwise false
3802 */
3803 public boolean validateAnnotationDeferErrors(JCAnnotation a) {
3804 boolean res = false;
3805 final Log.DiagnosticHandler diagHandler = new Log.DiscardDiagnosticHandler(log);
3806 try {
3807 res = validateAnnotation(a);
3808 } finally {
3809 log.popDiagnosticHandler(diagHandler);
3810 }
3811 return res;
3812 }
3813
3814 private boolean validateAnnotation(JCAnnotation a) {
3815 boolean isValid = true;
3816 AnnotationTypeMetadata metadata = a.annotationType.type.tsym.getAnnotationTypeMetadata();
3817
3818 // collect an inventory of the annotation elements
3819 Set<MethodSymbol> elements = metadata.getAnnotationElements();
3820
3821 // remove the ones that are assigned values
3822 for (JCTree arg : a.args) {
3823 if (!arg.hasTag(ASSIGN)) continue; // recovery
3824 JCAssign assign = (JCAssign)arg;
3825 Symbol m = TreeInfo.symbol(assign.lhs);
3826 if (m == null || m.type.isErroneous()) continue;
3827 if (!elements.remove(m)) {
3828 isValid = false;
3829 log.error(assign.lhs.pos(),
3830 Errors.DuplicateAnnotationMemberValue(m.name, a.type));
3831 }
3832 }
3833
3834 // all the remaining ones better have default values
3835 List<Name> missingDefaults = List.nil();
3836 Set<MethodSymbol> membersWithDefault = metadata.getAnnotationElementsWithDefault();
3837 for (MethodSymbol m : elements) {
3838 if (m.type.isErroneous())
3839 continue;
3840
3841 if (!membersWithDefault.contains(m))
3842 missingDefaults = missingDefaults.append(m.name);
3843 }
3844 missingDefaults = missingDefaults.reverse();
3845 if (missingDefaults.nonEmpty()) {
3846 isValid = false;
3847 Error errorKey = (missingDefaults.size() > 1)
3848 ? Errors.AnnotationMissingDefaultValue1(a.type, missingDefaults)
3849 : Errors.AnnotationMissingDefaultValue(a.type, missingDefaults);
3850 log.error(a.pos(), errorKey);
3851 }
3852
3853 return isValid && validateTargetAnnotationValue(a);
3854 }
3855
3856 /* Validate the special java.lang.annotation.Target annotation */
3857 boolean validateTargetAnnotationValue(JCAnnotation a) {
3858 // special case: java.lang.annotation.Target must not have
3859 // repeated values in its value member
3860 if (a.annotationType.type.tsym != syms.annotationTargetType.tsym ||
3861 a.args.tail == null)
3862 return true;
3863
3864 boolean isValid = true;
3865 if (!a.args.head.hasTag(ASSIGN)) return false; // error recovery
3866 JCAssign assign = (JCAssign) a.args.head;
3867 Symbol m = TreeInfo.symbol(assign.lhs);
3868 if (m.name != names.value) return false;
3869 JCTree rhs = assign.rhs;
3870 if (!rhs.hasTag(NEWARRAY)) return false;
3871 JCNewArray na = (JCNewArray) rhs;
3872 Set<Symbol> targets = new HashSet<>();
3873 for (JCTree elem : na.elems) {
3874 if (!targets.add(TreeInfo.symbol(elem))) {
3875 isValid = false;
3876 log.error(elem.pos(), Errors.RepeatedAnnotationTarget);
3877 }
3878 }
3879 return isValid;
3880 }
3881
3882 void checkDeprecatedAnnotation(DiagnosticPosition pos, Symbol s) {
3883 if (lint.isEnabled(LintCategory.DEP_ANN) && s.isDeprecatableViaAnnotation() &&
3884 (s.flags() & DEPRECATED) != 0 &&
3885 !syms.deprecatedType.isErroneous() &&
3886 s.attribute(syms.deprecatedType.tsym) == null) {
3887 log.warning(LintCategory.DEP_ANN,
3888 pos, Warnings.MissingDeprecatedAnnotation);
3889 }
3890 // Note: @Deprecated has no effect on local variables, parameters and package decls.
3891 if (lint.isEnabled(LintCategory.DEPRECATION) && !s.isDeprecatableViaAnnotation()) {
3892 if (!syms.deprecatedType.isErroneous() && s.attribute(syms.deprecatedType.tsym) != null) {
3893 log.warning(LintCategory.DEPRECATION, pos,
3894 Warnings.DeprecatedAnnotationHasNoEffect(Kinds.kindName(s)));
3895 }
3896 }
3897 }
3898
3899 void checkDeprecated(final DiagnosticPosition pos, final Symbol other, final Symbol s) {
3900 checkDeprecated(() -> pos, other, s);
3901 }
3902
3903 void checkDeprecated(Supplier<DiagnosticPosition> pos, final Symbol other, final Symbol s) {
3904 if ( (s.isDeprecatedForRemoval()
3905 || s.isDeprecated() && !other.isDeprecated())
3906 && (s.outermostClass() != other.outermostClass() || s.outermostClass() == null)
3907 && s.kind != Kind.PCK) {
3908 deferredLintHandler.report(() -> warnDeprecated(pos.get(), s));
3909 }
3910 }
3911
3912 void checkSunAPI(final DiagnosticPosition pos, final Symbol s) {
3913 if ((s.flags() & PROPRIETARY) != 0) {
3914 deferredLintHandler.report(() -> {
3915 log.mandatoryWarning(pos, Warnings.SunProprietary(s));
3916 });
3917 }
3918 }
3919
3920 void checkProfile(final DiagnosticPosition pos, final Symbol s) {
3921 if (profile != Profile.DEFAULT && (s.flags() & NOT_IN_PROFILE) != 0) {
3922 log.error(pos, Errors.NotInProfile(s, profile));
3923 }
3924 }
3925
3926 void checkPreview(DiagnosticPosition pos, Symbol other, Symbol s) {
3927 if ((s.flags() & PREVIEW_API) != 0 && !preview.participatesInPreview(syms, other, s) && !disablePreviewCheck) {
3928 if ((s.flags() & PREVIEW_REFLECTIVE) == 0) {
3929 if (!preview.isEnabled()) {
3930 log.error(pos, Errors.IsPreview(s));
3931 } else {
3932 preview.markUsesPreview(pos);
3933 deferredLintHandler.report(() -> warnPreviewAPI(pos, Warnings.IsPreview(s)));
3934 }
3935 } else {
3936 deferredLintHandler.report(() -> warnPreviewAPI(pos, Warnings.IsPreviewReflective(s)));
3937 }
3938 }
3939 if (preview.declaredUsingPreviewFeature(s)) {
3940 if (preview.isEnabled()) {
3941 //for preview disabled do presumably so not need to do anything?
3942 //If "s" is compiled from source, then there was an error for it already;
3943 //if "s" is from classfile, there already was an error for the classfile.
3944 preview.markUsesPreview(pos);
3945 deferredLintHandler.report(() -> warnDeclaredUsingPreview(pos, s));
3946 }
3947 }
3948 }
3949
3950 void checkRestricted(DiagnosticPosition pos, Symbol s) {
3951 if (s.kind == MTH && (s.flags() & RESTRICTED) != 0) {
3952 deferredLintHandler.report(() -> warnRestrictedAPI(pos, s));
3953 }
3954 }
3955
3956 /* *************************************************************************
3957 * Check for recursive annotation elements.
3958 **************************************************************************/
3959
3960 /** Check for cycles in the graph of annotation elements.
3961 */
3962 void checkNonCyclicElements(JCClassDecl tree) {
3963 if ((tree.sym.flags_field & ANNOTATION) == 0) return;
3964 Assert.check((tree.sym.flags_field & LOCKED) == 0);
3965 try {
3966 tree.sym.flags_field |= LOCKED;
3967 for (JCTree def : tree.defs) {
3968 if (!def.hasTag(METHODDEF)) continue;
3969 JCMethodDecl meth = (JCMethodDecl)def;
3970 checkAnnotationResType(meth.pos(), meth.restype.type);
3971 }
3972 } finally {
3973 tree.sym.flags_field &= ~LOCKED;
3974 tree.sym.flags_field |= ACYCLIC_ANN;
3975 }
3976 }
3977
3978 void checkNonCyclicElementsInternal(DiagnosticPosition pos, TypeSymbol tsym) {
3979 if ((tsym.flags_field & ACYCLIC_ANN) != 0)
3980 return;
3981 if ((tsym.flags_field & LOCKED) != 0) {
3982 log.error(pos, Errors.CyclicAnnotationElement(tsym));
3983 return;
3984 }
3985 try {
3986 tsym.flags_field |= LOCKED;
3987 for (Symbol s : tsym.members().getSymbols(NON_RECURSIVE)) {
3988 if (s.kind != MTH)
3989 continue;
3990 checkAnnotationResType(pos, ((MethodSymbol)s).type.getReturnType());
3991 }
3992 } finally {
3993 tsym.flags_field &= ~LOCKED;
3994 tsym.flags_field |= ACYCLIC_ANN;
3995 }
3996 }
3997
3998 void checkAnnotationResType(DiagnosticPosition pos, Type type) {
3999 switch (type.getTag()) {
4000 case CLASS:
4001 if ((type.tsym.flags() & ANNOTATION) != 0)
4002 checkNonCyclicElementsInternal(pos, type.tsym);
4003 break;
4004 case ARRAY:
4005 checkAnnotationResType(pos, types.elemtype(type));
4006 break;
4007 default:
4008 break; // int etc
4009 }
4010 }
4011
4012 /* *************************************************************************
4013 * Check for cycles in the constructor call graph.
4014 **************************************************************************/
4015
4016 /** Check for cycles in the graph of constructors calling other
4017 * constructors.
4018 */
4019 void checkCyclicConstructors(JCClassDecl tree) {
4020 // use LinkedHashMap so we generate errors deterministically
4021 Map<Symbol,Symbol> callMap = new LinkedHashMap<>();
4022
4023 // enter each constructor this-call into the map
4024 for (List<JCTree> l = tree.defs; l.nonEmpty(); l = l.tail) {
4025 if (!TreeInfo.isConstructor(l.head))
4026 continue;
4027 JCMethodDecl meth = (JCMethodDecl)l.head;
4028 JCMethodInvocation app = TreeInfo.findConstructorCall(meth);
4029 if (app != null && TreeInfo.name(app.meth) == names._this) {
4030 callMap.put(meth.sym, TreeInfo.symbol(app.meth));
4031 } else {
4032 meth.sym.flags_field |= ACYCLIC;
4033 }
4034 }
4035
4036 // Check for cycles in the map
4037 Symbol[] ctors = new Symbol[0];
4038 ctors = callMap.keySet().toArray(ctors);
4039 for (Symbol caller : ctors) {
4040 checkCyclicConstructor(tree, caller, callMap);
4041 }
4042 }
4043
4044 /** Look in the map to see if the given constructor is part of a
4045 * call cycle.
4046 */
4047 private void checkCyclicConstructor(JCClassDecl tree, Symbol ctor,
4048 Map<Symbol,Symbol> callMap) {
4049 if (ctor != null && (ctor.flags_field & ACYCLIC) == 0) {
4050 if ((ctor.flags_field & LOCKED) != 0) {
4051 log.error(TreeInfo.diagnosticPositionFor(ctor, tree, false, t -> t.hasTag(IDENT)),
4052 Errors.RecursiveCtorInvocation);
4053 } else {
4054 ctor.flags_field |= LOCKED;
4055 checkCyclicConstructor(tree, callMap.remove(ctor), callMap);
4056 ctor.flags_field &= ~LOCKED;
4057 }
4058 ctor.flags_field |= ACYCLIC;
4059 }
4060 }
4061
4062 /* *************************************************************************
4063 * Verify the proper placement of super()/this() calls.
4064 *
4065 * - super()/this() may only appear in constructors
4066 * - There must be at most one super()/this() call per constructor
4067 * - The super()/this() call, if any, must be a top-level statement in the
4068 * constructor, i.e., not nested inside any other statement or block
4069 * - There must be no return statements prior to the super()/this() call
4070 **************************************************************************/
4071
4072 void checkSuperInitCalls(JCClassDecl tree) {
4073 new SuperThisChecker().check(tree);
4074 }
4075
4076 private class SuperThisChecker extends TreeScanner {
4077
4078 // Match this scan stack: 1=JCMethodDecl, 2=JCExpressionStatement, 3=JCMethodInvocation
4079 private static final int MATCH_SCAN_DEPTH = 3;
4080
4081 private boolean constructor; // is this method a constructor?
4082 private boolean firstStatement; // at the first statement in method?
4083 private JCReturn earlyReturn; // first return prior to the super()/init(), if any
4084 private Name initCall; // whichever of "super" or "init" we've seen already
4085 private int scanDepth; // current scan recursion depth in method body
4086
4087 public void check(JCClassDecl classDef) {
4088 scan(classDef.defs);
4089 }
4090
4091 @Override
4092 public void visitMethodDef(JCMethodDecl tree) {
4093 Assert.check(!constructor);
4094 Assert.check(earlyReturn == null);
4095 Assert.check(initCall == null);
4096 Assert.check(scanDepth == 1);
4097
4098 // Initialize state for this method
4099 constructor = TreeInfo.isConstructor(tree);
4100 try {
4101
4102 // Scan method body
4103 if (tree.body != null) {
4104 firstStatement = true;
4105 for (List<JCStatement> l = tree.body.stats; l.nonEmpty(); l = l.tail) {
4106 scan(l.head);
4107 firstStatement = false;
4108 }
4109 }
4110
4111 // Verify no 'return' seen prior to an explicit super()/this() call
4112 if (constructor && earlyReturn != null && initCall != null)
4113 log.error(earlyReturn.pos(), Errors.ReturnBeforeSuperclassInitialized);
4114 } finally {
4115 firstStatement = false;
4116 constructor = false;
4117 earlyReturn = null;
4118 initCall = null;
4119 }
4120 }
4121
4122 @Override
4123 public void scan(JCTree tree) {
4124 scanDepth++;
4125 try {
4126 super.scan(tree);
4127 } finally {
4128 scanDepth--;
4129 }
4130 }
4131
4132 @Override
4133 public void visitApply(JCMethodInvocation apply) {
4134 do {
4135
4136 // Is this a super() or this() call?
4137 Name methodName = TreeInfo.name(apply.meth);
4138 if (methodName != names._super && methodName != names._this)
4139 break;
4140
4141 // super()/this() calls must only appear in a constructor
4142 if (!constructor) {
4143 log.error(apply.pos(), Errors.CallMustOnlyAppearInCtor);
4144 break;
4145 }
4146
4147 // super()/this() calls must be a top level statement
4148 if (scanDepth != MATCH_SCAN_DEPTH) {
4149 log.error(apply.pos(), Errors.CtorCallsNotAllowedHere);
4150 break;
4151 }
4152
4153 // super()/this() calls must not appear more than once
4154 if (initCall != null) {
4155 log.error(apply.pos(), Errors.RedundantSuperclassInit);
4156 break;
4157 }
4158
4159 // If super()/this() isn't first, require flexible constructors feature
4160 if (!firstStatement)
4161 preview.checkSourceLevel(apply.pos(), Feature.SUPER_INIT);
4162
4163 // We found a legitimate super()/this() call; remember it
4164 initCall = methodName;
4165 } while (false);
4166
4167 // Proceed
4168 super.visitApply(apply);
4169 }
4170
4171 @Override
4172 public void visitReturn(JCReturn tree) {
4173 if (constructor && initCall == null && earlyReturn == null)
4174 earlyReturn = tree; // we have seen a return but not (yet) a super()/this()
4175 super.visitReturn(tree);
4176 }
4177
4178 @Override
4179 public void visitClassDef(JCClassDecl tree) {
4180 // don't descend any further
4181 }
4182 }
4183
4184 /* *************************************************************************
4185 * Miscellaneous
4186 **************************************************************************/
4187
4188 /**
4189 * Check for division by integer constant zero
4190 * @param pos Position for error reporting.
4191 * @param operator The operator for the expression
4192 * @param operand The right hand operand for the expression
4193 */
4194 void checkDivZero(final DiagnosticPosition pos, Symbol operator, Type operand) {
4195 if (operand.constValue() != null
4196 && operand.getTag().isSubRangeOf(LONG)
4197 && ((Number) (operand.constValue())).longValue() == 0) {
4198 int opc = ((OperatorSymbol)operator).opcode;
4199 if (opc == ByteCodes.idiv || opc == ByteCodes.imod
4200 || opc == ByteCodes.ldiv || opc == ByteCodes.lmod) {
4201 deferredLintHandler.report(() -> warnDivZero(pos));
4202 }
4203 }
4204 }
4205
4206 /**
4207 * Check for possible loss of precission
4208 * @param pos Position for error reporting.
4209 * @param found The computed type of the tree
4210 * @param req The computed type of the tree
4211 */
4212 void checkLossOfPrecision(final DiagnosticPosition pos, Type found, Type req) {
4213 if (found.isNumeric() && req.isNumeric() && !types.isAssignable(found, req)) {
4214 deferredLintHandler.report(() -> {
4215 if (lint.isEnabled(LintCategory.LOSSY_CONVERSIONS))
4216 log.warning(LintCategory.LOSSY_CONVERSIONS,
4217 pos, Warnings.PossibleLossOfPrecision(found, req));
4218 });
4219 }
4220 }
4221
4222 /**
4223 * Check for empty statements after if
4224 */
4225 void checkEmptyIf(JCIf tree) {
4226 if (tree.thenpart.hasTag(SKIP) && tree.elsepart == null &&
4227 lint.isEnabled(LintCategory.EMPTY))
4228 log.warning(LintCategory.EMPTY, tree.thenpart.pos(), Warnings.EmptyIf);
4229 }
4230
4231 /** Check that symbol is unique in given scope.
4232 * @param pos Position for error reporting.
4233 * @param sym The symbol.
4234 * @param s The scope.
4235 */
4236 boolean checkUnique(DiagnosticPosition pos, Symbol sym, Scope s) {
4237 if (sym.type.isErroneous())
4238 return true;
4239 if (sym.owner.name == names.any) return false;
4240 for (Symbol byName : s.getSymbolsByName(sym.name, NON_RECURSIVE)) {
4241 if (sym != byName &&
4242 (byName.flags() & CLASH) == 0 &&
4243 sym.kind == byName.kind &&
4244 sym.name != names.error &&
4245 (sym.kind != MTH ||
4246 types.hasSameArgs(sym.type, byName.type) ||
4247 types.hasSameArgs(types.erasure(sym.type), types.erasure(byName.type)))) {
4248 if ((sym.flags() & VARARGS) != (byName.flags() & VARARGS)) {
4249 sym.flags_field |= CLASH;
4250 varargsDuplicateError(pos, sym, byName);
4251 return true;
4252 } else if (sym.kind == MTH && !types.hasSameArgs(sym.type, byName.type, false)) {
4253 duplicateErasureError(pos, sym, byName);
4254 sym.flags_field |= CLASH;
4255 return true;
4256 } else if ((sym.flags() & MATCH_BINDING) != 0 &&
4257 (byName.flags() & MATCH_BINDING) != 0 &&
4258 (byName.flags() & MATCH_BINDING_TO_OUTER) == 0) {
4259 if (!sym.type.isErroneous()) {
4260 log.error(pos, Errors.MatchBindingExists);
4261 sym.flags_field |= CLASH;
4262 }
4263 return false;
4264 } else {
4265 duplicateError(pos, byName);
4266 return false;
4267 }
4268 }
4269 }
4270 return true;
4271 }
4272
4273 /** Report duplicate declaration error.
4274 */
4275 void duplicateErasureError(DiagnosticPosition pos, Symbol sym1, Symbol sym2) {
4276 if (!sym1.type.isErroneous() && !sym2.type.isErroneous()) {
4277 log.error(pos, Errors.NameClashSameErasure(sym1, sym2));
4278 }
4279 }
4280
4281 /**Check that types imported through the ordinary imports don't clash with types imported
4282 * by other (static or ordinary) imports. Note that two static imports may import two clashing
4283 * types without an error on the imports.
4284 * @param toplevel The toplevel tree for which the test should be performed.
4285 */
4286 void checkImportsUnique(JCCompilationUnit toplevel) {
4287 WriteableScope ordinallyImportedSoFar = WriteableScope.create(toplevel.packge);
4288 WriteableScope staticallyImportedSoFar = WriteableScope.create(toplevel.packge);
4289 WriteableScope topLevelScope = toplevel.toplevelScope;
4290
4291 for (JCTree def : toplevel.defs) {
4292 if (!def.hasTag(IMPORT))
4293 continue;
4294
4295 JCImport imp = (JCImport) def;
4296
4297 if (imp.importScope == null)
4298 continue;
4299
4300 for (Symbol sym : imp.importScope.getSymbols(sym -> sym.kind == TYP)) {
4301 if (imp.isStatic()) {
4302 checkUniqueImport(imp.pos(), ordinallyImportedSoFar, staticallyImportedSoFar, topLevelScope, sym, true);
4303 staticallyImportedSoFar.enter(sym);
4304 } else {
4305 checkUniqueImport(imp.pos(), ordinallyImportedSoFar, staticallyImportedSoFar, topLevelScope, sym, false);
4306 ordinallyImportedSoFar.enter(sym);
4307 }
4308 }
4309
4310 imp.importScope = null;
4311 }
4312 }
4313
4314 /** Check that single-type import is not already imported or top-level defined,
4315 * but make an exception for two single-type imports which denote the same type.
4316 * @param pos Position for error reporting.
4317 * @param ordinallyImportedSoFar A Scope containing types imported so far through
4318 * ordinary imports.
4319 * @param staticallyImportedSoFar A Scope containing types imported so far through
4320 * static imports.
4321 * @param topLevelScope The current file's top-level Scope
4322 * @param sym The symbol.
4323 * @param staticImport Whether or not this was a static import
4324 */
4325 private boolean checkUniqueImport(DiagnosticPosition pos, Scope ordinallyImportedSoFar,
4326 Scope staticallyImportedSoFar, Scope topLevelScope,
4327 Symbol sym, boolean staticImport) {
4328 Predicate<Symbol> duplicates = candidate -> candidate != sym && !candidate.type.isErroneous();
4329 Symbol ordinaryClashing = ordinallyImportedSoFar.findFirst(sym.name, duplicates);
4330 Symbol staticClashing = null;
4331 if (ordinaryClashing == null && !staticImport) {
4332 staticClashing = staticallyImportedSoFar.findFirst(sym.name, duplicates);
4333 }
4334 if (ordinaryClashing != null || staticClashing != null) {
4335 if (ordinaryClashing != null)
4336 log.error(pos, Errors.AlreadyDefinedSingleImport(ordinaryClashing));
4337 else
4338 log.error(pos, Errors.AlreadyDefinedStaticSingleImport(staticClashing));
4339 return false;
4340 }
4341 Symbol clashing = topLevelScope.findFirst(sym.name, duplicates);
4342 if (clashing != null) {
4343 log.error(pos, Errors.AlreadyDefinedThisUnit(clashing));
4344 return false;
4345 }
4346 return true;
4347 }
4348
4349 /** Check that a qualified name is in canonical form (for import decls).
4350 */
4351 public void checkCanonical(JCTree tree) {
4352 if (!isCanonical(tree))
4353 log.error(tree.pos(),
4354 Errors.ImportRequiresCanonical(TreeInfo.symbol(tree)));
4355 }
4356 // where
4357 private boolean isCanonical(JCTree tree) {
4358 while (tree.hasTag(SELECT)) {
4359 JCFieldAccess s = (JCFieldAccess) tree;
4360 if (s.sym.owner.getQualifiedName() != TreeInfo.symbol(s.selected).getQualifiedName())
4361 return false;
4362 tree = s.selected;
4363 }
4364 return true;
4365 }
4366
4367 /** Check that an auxiliary class is not accessed from any other file than its own.
4368 */
4369 void checkForBadAuxiliaryClassAccess(DiagnosticPosition pos, Env<AttrContext> env, ClassSymbol c) {
4370 if (lint.isEnabled(Lint.LintCategory.AUXILIARYCLASS) &&
4371 (c.flags() & AUXILIARY) != 0 &&
4372 rs.isAccessible(env, c) &&
4373 !fileManager.isSameFile(c.sourcefile, env.toplevel.sourcefile))
4374 {
4375 log.warning(pos,
4376 Warnings.AuxiliaryClassAccessedFromOutsideOfItsSourceFile(c, c.sourcefile));
4377 }
4378 }
4379
4380 /**
4381 * Check for a default constructor in an exported package.
4382 */
4383 void checkDefaultConstructor(ClassSymbol c, DiagnosticPosition pos) {
4384 if (lint.isEnabled(LintCategory.MISSING_EXPLICIT_CTOR) &&
4385 ((c.flags() & (ENUM | RECORD)) == 0) &&
4386 !c.isAnonymous() &&
4387 ((c.flags() & (PUBLIC | PROTECTED)) != 0) &&
4388 Feature.MODULES.allowedInSource(source)) {
4389 NestingKind nestingKind = c.getNestingKind();
4390 switch (nestingKind) {
4391 case ANONYMOUS,
4392 LOCAL -> {return;}
4393 case TOP_LEVEL -> {;} // No additional checks needed
4394 case MEMBER -> {
4395 // For nested member classes, all the enclosing
4396 // classes must be public or protected.
4397 Symbol owner = c.owner;
4398 while (owner != null && owner.kind == TYP) {
4399 if ((owner.flags() & (PUBLIC | PROTECTED)) == 0)
4400 return;
4401 owner = owner.owner;
4402 }
4403 }
4404 }
4405
4406 // Only check classes in named packages exported by its module
4407 PackageSymbol pkg = c.packge();
4408 if (!pkg.isUnnamed()) {
4409 ModuleSymbol modle = pkg.modle;
4410 for (ExportsDirective exportDir : modle.exports) {
4411 // Report warning only if the containing
4412 // package is unconditionally exported
4413 if (exportDir.packge.equals(pkg)) {
4414 if (exportDir.modules == null || exportDir.modules.isEmpty()) {
4415 // Warning may be suppressed by
4416 // annotations; check again for being
4417 // enabled in the deferred context.
4418 deferredLintHandler.report(() -> {
4419 if (lint.isEnabled(LintCategory.MISSING_EXPLICIT_CTOR))
4420 log.warning(LintCategory.MISSING_EXPLICIT_CTOR,
4421 pos, Warnings.MissingExplicitCtor(c, pkg, modle));
4422 });
4423 } else {
4424 return;
4425 }
4426 }
4427 }
4428 }
4429 }
4430 return;
4431 }
4432
4433 private class ConversionWarner extends Warner {
4434 final String uncheckedKey;
4435 final Type found;
4436 final Type expected;
4437 public ConversionWarner(DiagnosticPosition pos, String uncheckedKey, Type found, Type expected) {
4438 super(pos);
4439 this.uncheckedKey = uncheckedKey;
4440 this.found = found;
4441 this.expected = expected;
4442 }
4443
4444 @Override
4445 public void warn(LintCategory lint) {
4446 boolean warned = this.warned;
4447 super.warn(lint);
4448 if (warned) return; // suppress redundant diagnostics
4449 switch (lint) {
4450 case UNCHECKED:
4451 Check.this.warnUnchecked(pos(), Warnings.ProbFoundReq(diags.fragment(uncheckedKey), found, expected));
4452 break;
4453 case VARARGS:
4454 if (method != null &&
4455 method.attribute(syms.trustMeType.tsym) != null &&
4456 isTrustMeAllowedOnMethod(method) &&
4457 !types.isReifiable(method.type.getParameterTypes().last())) {
4458 Check.this.warnUnsafeVararg(pos(), Warnings.VarargsUnsafeUseVarargsParam(method.params.last()));
4459 }
4460 break;
4461 default:
4462 throw new AssertionError("Unexpected lint: " + lint);
4463 }
4464 }
4465 }
4466
4467 public Warner castWarner(DiagnosticPosition pos, Type found, Type expected) {
4468 return new ConversionWarner(pos, "unchecked.cast.to.type", found, expected);
4469 }
4470
4471 public Warner convertWarner(DiagnosticPosition pos, Type found, Type expected) {
4472 return new ConversionWarner(pos, "unchecked.assign", found, expected);
4473 }
4474
4475 public void checkFunctionalInterface(JCClassDecl tree, ClassSymbol cs) {
4476 Compound functionalType = cs.attribute(syms.functionalInterfaceType.tsym);
4477
4478 if (functionalType != null) {
4479 try {
4480 types.findDescriptorSymbol((TypeSymbol)cs);
4481 } catch (Types.FunctionDescriptorLookupError ex) {
4482 DiagnosticPosition pos = tree.pos();
4483 for (JCAnnotation a : tree.getModifiers().annotations) {
4484 if (a.annotationType.type.tsym == syms.functionalInterfaceType.tsym) {
4485 pos = a.pos();
4486 break;
4487 }
4488 }
4489 log.error(pos, Errors.BadFunctionalIntfAnno1(ex.getDiagnostic()));
4490 }
4491 }
4492 }
4493
4494 public void checkImportsResolvable(final JCCompilationUnit toplevel) {
4495 for (final JCImport imp : toplevel.getImports()) {
4496 if (!imp.staticImport || !imp.qualid.hasTag(SELECT))
4497 continue;
4498 final JCFieldAccess select = imp.qualid;
4499 final Symbol origin;
4500 if (select.name == names.asterisk || (origin = TreeInfo.symbol(select.selected)) == null || origin.kind != TYP)
4501 continue;
4502
4503 TypeSymbol site = (TypeSymbol) TreeInfo.symbol(select.selected);
4504 if (!checkTypeContainsImportableElement(site, site, toplevel.packge, select.name, new HashSet<Symbol>())) {
4505 log.error(imp.pos(),
4506 Errors.CantResolveLocation(KindName.STATIC,
4507 select.name,
4508 null,
4509 null,
4510 Fragments.Location(kindName(site),
4511 site,
4512 null)));
4513 }
4514 }
4515 }
4516
4517 // Check that packages imported are in scope (JLS 7.4.3, 6.3, 6.5.3.1, 6.5.3.2)
4518 public void checkImportedPackagesObservable(final JCCompilationUnit toplevel) {
4519 OUTER: for (JCImport imp : toplevel.getImports()) {
4520 if (!imp.staticImport && TreeInfo.name(imp.qualid) == names.asterisk) {
4521 TypeSymbol tsym = imp.qualid.selected.type.tsym;
4522 if (tsym.kind == PCK && tsym.members().isEmpty() &&
4523 !(Feature.IMPORT_ON_DEMAND_OBSERVABLE_PACKAGES.allowedInSource(source) && tsym.exists())) {
4524 log.error(DiagnosticFlag.RESOLVE_ERROR, imp.pos, Errors.DoesntExist(tsym));
4525 }
4526 }
4527 }
4528 }
4529
4530 private boolean checkTypeContainsImportableElement(TypeSymbol tsym, TypeSymbol origin, PackageSymbol packge, Name name, Set<Symbol> processed) {
4531 if (tsym == null || !processed.add(tsym))
4532 return false;
4533
4534 // also search through inherited names
4535 if (checkTypeContainsImportableElement(types.supertype(tsym.type).tsym, origin, packge, name, processed))
4536 return true;
4537
4538 for (Type t : types.interfaces(tsym.type))
4539 if (checkTypeContainsImportableElement(t.tsym, origin, packge, name, processed))
4540 return true;
4541
4542 for (Symbol sym : tsym.members().getSymbolsByName(name)) {
4543 if (sym.isStatic() &&
4544 importAccessible(sym, packge) &&
4545 sym.isMemberOf(origin, types)) {
4546 return true;
4547 }
4548 }
4549
4550 return false;
4551 }
4552
4553 // is the sym accessible everywhere in packge?
4554 public boolean importAccessible(Symbol sym, PackageSymbol packge) {
4555 try {
4556 int flags = (int)(sym.flags() & AccessFlags);
4557 switch (flags) {
4558 default:
4559 case PUBLIC:
4560 return true;
4561 case PRIVATE:
4562 return false;
4563 case 0:
4564 case PROTECTED:
4565 return sym.packge() == packge;
4566 }
4567 } catch (ClassFinder.BadClassFile err) {
4568 throw err;
4569 } catch (CompletionFailure ex) {
4570 return false;
4571 }
4572 }
4573
4574 public Type checkProcessorType(JCExpression processor, Type resultType, Env<AttrContext> env) {
4575 Type processorType = processor.type;
4576 Type interfaceType = types.asSuper(processorType, syms.processorType.tsym);
4577
4578 if (interfaceType != null) {
4579 List<Type> typeArguments = interfaceType.getTypeArguments();
4580
4581 if (typeArguments.size() == 2) {
4582 resultType = typeArguments.head;
4583 } else {
4584 resultType = syms.objectType;
4585 }
4586 } else {
4587 log.error(DiagnosticFlag.RESOLVE_ERROR, processor.pos,
4588 Errors.NotAProcessorType(processorType.tsym));
4589 }
4590
4591 return resultType;
4592 }
4593
4594 public void checkLeaksNotAccessible(Env<AttrContext> env, JCClassDecl check) {
4595 JCCompilationUnit toplevel = env.toplevel;
4596
4597 if ( toplevel.modle == syms.unnamedModule
4598 || toplevel.modle == syms.noModule
4599 || (check.sym.flags() & COMPOUND) != 0) {
4600 return ;
4601 }
4602
4603 ExportsDirective currentExport = findExport(toplevel.packge);
4604
4605 if ( currentExport == null //not exported
4606 || currentExport.modules != null) //don't check classes in qualified export
4607 return ;
4608
4609 new TreeScanner() {
4610 Lint lint = env.info.lint;
4611 boolean inSuperType;
4612
4613 @Override
4614 public void visitBlock(JCBlock tree) {
4615 }
4616 @Override
4617 public void visitMethodDef(JCMethodDecl tree) {
4618 if (!isAPISymbol(tree.sym))
4619 return;
4620 Lint prevLint = lint;
4621 try {
4622 lint = lint.augment(tree.sym);
4623 if (lint.isEnabled(LintCategory.EXPORTS)) {
4624 super.visitMethodDef(tree);
4625 }
4626 } finally {
4627 lint = prevLint;
4628 }
4629 }
4630 @Override
4631 public void visitVarDef(JCVariableDecl tree) {
4632 if (!isAPISymbol(tree.sym) && tree.sym.owner.kind != MTH)
4633 return;
4634 Lint prevLint = lint;
4635 try {
4636 lint = lint.augment(tree.sym);
4637 if (lint.isEnabled(LintCategory.EXPORTS)) {
4638 scan(tree.mods);
4639 scan(tree.vartype);
4640 }
4641 } finally {
4642 lint = prevLint;
4643 }
4644 }
4645 @Override
4646 public void visitClassDef(JCClassDecl tree) {
4647 if (tree != check)
4648 return ;
4649
4650 if (!isAPISymbol(tree.sym))
4651 return ;
4652
4653 Lint prevLint = lint;
4654 try {
4655 lint = lint.augment(tree.sym);
4656 if (lint.isEnabled(LintCategory.EXPORTS)) {
4657 scan(tree.mods);
4658 scan(tree.typarams);
4659 try {
4660 inSuperType = true;
4661 scan(tree.extending);
4662 scan(tree.implementing);
4663 } finally {
4664 inSuperType = false;
4665 }
4666 scan(tree.defs);
4667 }
4668 } finally {
4669 lint = prevLint;
4670 }
4671 }
4672 @Override
4673 public void visitTypeApply(JCTypeApply tree) {
4674 scan(tree.clazz);
4675 boolean oldInSuperType = inSuperType;
4676 try {
4677 inSuperType = false;
4678 scan(tree.arguments);
4679 } finally {
4680 inSuperType = oldInSuperType;
4681 }
4682 }
4683 @Override
4684 public void visitIdent(JCIdent tree) {
4685 Symbol sym = TreeInfo.symbol(tree);
4686 if (sym.kind == TYP && !sym.type.hasTag(TYPEVAR)) {
4687 checkVisible(tree.pos(), sym, toplevel.packge, inSuperType);
4688 }
4689 }
4690
4691 @Override
4692 public void visitSelect(JCFieldAccess tree) {
4693 Symbol sym = TreeInfo.symbol(tree);
4694 Symbol sitesym = TreeInfo.symbol(tree.selected);
4695 if (sym.kind == TYP && sitesym.kind == PCK) {
4696 checkVisible(tree.pos(), sym, toplevel.packge, inSuperType);
4697 } else {
4698 super.visitSelect(tree);
4699 }
4700 }
4701
4702 @Override
4703 public void visitAnnotation(JCAnnotation tree) {
4704 if (tree.attribute.type.tsym.getAnnotation(java.lang.annotation.Documented.class) != null)
4705 super.visitAnnotation(tree);
4706 }
4707
4708 }.scan(check);
4709 }
4710 //where:
4711 private ExportsDirective findExport(PackageSymbol pack) {
4712 for (ExportsDirective d : pack.modle.exports) {
4713 if (d.packge == pack)
4714 return d;
4715 }
4716
4717 return null;
4718 }
4719 private boolean isAPISymbol(Symbol sym) {
4720 while (sym.kind != PCK) {
4721 if ((sym.flags() & Flags.PUBLIC) == 0 && (sym.flags() & Flags.PROTECTED) == 0) {
4722 return false;
4723 }
4724 sym = sym.owner;
4725 }
4726 return true;
4727 }
4728 private void checkVisible(DiagnosticPosition pos, Symbol what, PackageSymbol inPackage, boolean inSuperType) {
4729 if (!isAPISymbol(what) && !inSuperType) { //package private/private element
4730 log.warning(LintCategory.EXPORTS, pos, Warnings.LeaksNotAccessible(kindName(what), what, what.packge().modle));
4731 return ;
4732 }
4733
4734 PackageSymbol whatPackage = what.packge();
4735 ExportsDirective whatExport = findExport(whatPackage);
4736 ExportsDirective inExport = findExport(inPackage);
4737
4738 if (whatExport == null) { //package not exported:
4739 log.warning(LintCategory.EXPORTS, pos, Warnings.LeaksNotAccessibleUnexported(kindName(what), what, what.packge().modle));
4740 return ;
4741 }
4742
4743 if (whatExport.modules != null) {
4744 if (inExport.modules == null || !whatExport.modules.containsAll(inExport.modules)) {
4745 log.warning(LintCategory.EXPORTS, pos, Warnings.LeaksNotAccessibleUnexportedQualified(kindName(what), what, what.packge().modle));
4746 }
4747 }
4748
4749 if (whatPackage.modle != inPackage.modle && whatPackage.modle != syms.java_base) {
4750 //check that relativeTo.modle requires transitive what.modle, somehow:
4751 List<ModuleSymbol> todo = List.of(inPackage.modle);
4752
4753 while (todo.nonEmpty()) {
4754 ModuleSymbol current = todo.head;
4755 todo = todo.tail;
4756 if (current == whatPackage.modle)
4757 return ; //OK
4758 if ((current.flags() & Flags.AUTOMATIC_MODULE) != 0)
4759 continue; //for automatic modules, don't look into their dependencies
4760 for (RequiresDirective req : current.requires) {
4761 if (req.isTransitive()) {
4762 todo = todo.prepend(req.module);
4763 }
4764 }
4765 }
4766
4767 log.warning(LintCategory.EXPORTS, pos, Warnings.LeaksNotAccessibleNotRequiredTransitive(kindName(what), what, what.packge().modle));
4768 }
4769 }
4770
4771 void checkModuleExists(final DiagnosticPosition pos, ModuleSymbol msym) {
4772 if (msym.kind != MDL) {
4773 deferredLintHandler.report(() -> {
4774 if (lint.isEnabled(LintCategory.MODULE))
4775 log.warning(LintCategory.MODULE, pos, Warnings.ModuleNotFound(msym));
4776 });
4777 }
4778 }
4779
4780 void checkPackageExistsForOpens(final DiagnosticPosition pos, PackageSymbol packge) {
4781 if (packge.members().isEmpty() &&
4782 ((packge.flags() & Flags.HAS_RESOURCE) == 0)) {
4783 deferredLintHandler.report(() -> {
4784 if (lint.isEnabled(LintCategory.OPENS))
4785 log.warning(pos, Warnings.PackageEmptyOrNotFound(packge));
4786 });
4787 }
4788 }
4789
4790 void checkModuleRequires(final DiagnosticPosition pos, final RequiresDirective rd) {
4791 if ((rd.module.flags() & Flags.AUTOMATIC_MODULE) != 0) {
4792 deferredLintHandler.report(() -> {
4793 if (rd.isTransitive() && lint.isEnabled(LintCategory.REQUIRES_TRANSITIVE_AUTOMATIC)) {
4794 log.warning(pos, Warnings.RequiresTransitiveAutomatic);
4795 } else if (lint.isEnabled(LintCategory.REQUIRES_AUTOMATIC)) {
4796 log.warning(pos, Warnings.RequiresAutomatic);
4797 }
4798 });
4799 }
4800 }
4801
4802 /**
4803 * Verify the case labels conform to the constraints. Checks constraints related
4804 * combinations of patterns and other labels.
4805 *
4806 * @param cases the cases that should be checked.
4807 */
4808 void checkSwitchCaseStructure(List<JCCase> cases) {
4809 for (List<JCCase> l = cases; l.nonEmpty(); l = l.tail) {
4810 JCCase c = l.head;
4811 if (c.labels.head instanceof JCConstantCaseLabel constLabel) {
4812 if (TreeInfo.isNull(constLabel.expr)) {
4813 if (c.labels.tail.nonEmpty()) {
4814 if (c.labels.tail.head instanceof JCDefaultCaseLabel defLabel) {
4815 if (c.labels.tail.tail.nonEmpty()) {
4816 log.error(c.labels.tail.tail.head.pos(), Errors.InvalidCaseLabelCombination);
4817 }
4818 } else {
4819 log.error(c.labels.tail.head.pos(), Errors.InvalidCaseLabelCombination);
4820 }
4821 }
4822 } else {
4823 for (JCCaseLabel label : c.labels.tail) {
4824 if (!(label instanceof JCConstantCaseLabel) || TreeInfo.isNullCaseLabel(label)) {
4825 log.error(label.pos(), Errors.InvalidCaseLabelCombination);
4826 break;
4827 }
4828 }
4829 }
4830 } else if (c.labels.tail.nonEmpty()) {
4831 var patterCaseLabels = c.labels.stream().filter(ll -> ll instanceof JCPatternCaseLabel).map(cl -> (JCPatternCaseLabel)cl);
4832 var allUnderscore = patterCaseLabels.allMatch(pcl -> !hasBindings(pcl.getPattern()));
4833
4834 if (!allUnderscore) {
4835 log.error(c.labels.tail.head.pos(), Errors.FlowsThroughFromPattern);
4836 }
4837
4838 boolean allPatternCaseLabels = c.labels.stream().allMatch(p -> p instanceof JCPatternCaseLabel);
4839
4840 if (allPatternCaseLabels) {
4841 preview.checkSourceLevel(c.labels.tail.head.pos(), Feature.UNNAMED_VARIABLES);
4842 }
4843
4844 for (JCCaseLabel label : c.labels.tail) {
4845 if (label instanceof JCConstantCaseLabel) {
4846 log.error(label.pos(), Errors.InvalidCaseLabelCombination);
4847 break;
4848 }
4849 }
4850 }
4851 }
4852
4853 boolean isCaseStatementGroup = cases.nonEmpty() &&
4854 cases.head.caseKind == CaseTree.CaseKind.STATEMENT;
4855
4856 if (isCaseStatementGroup) {
4857 boolean previousCompletessNormally = false;
4858 for (List<JCCase> l = cases; l.nonEmpty(); l = l.tail) {
4859 JCCase c = l.head;
4860 if (previousCompletessNormally &&
4861 c.stats.nonEmpty() &&
4862 c.labels.head instanceof JCPatternCaseLabel patternLabel &&
4863 (hasBindings(patternLabel.pat) || hasBindings(c.guard))) {
4864 log.error(c.labels.head.pos(), Errors.FlowsThroughToPattern);
4865 } else if (c.stats.isEmpty() &&
4866 c.labels.head instanceof JCPatternCaseLabel patternLabel &&
4867 (hasBindings(patternLabel.pat) || hasBindings(c.guard)) &&
4868 hasStatements(l.tail)) {
4869 log.error(c.labels.head.pos(), Errors.FlowsThroughFromPattern);
4870 }
4871 previousCompletessNormally = c.completesNormally;
4872 }
4873 }
4874 }
4875
4876 boolean hasBindings(JCTree p) {
4877 boolean[] bindings = new boolean[1];
4878
4879 new TreeScanner() {
4880 @Override
4881 public void visitBindingPattern(JCBindingPattern tree) {
4882 bindings[0] = !tree.var.sym.isUnnamedVariable();
4883 super.visitBindingPattern(tree);
4884 }
4885 }.scan(p);
4886
4887 return bindings[0];
4888 }
4889
4890 boolean hasStatements(List<JCCase> cases) {
4891 for (List<JCCase> l = cases; l.nonEmpty(); l = l.tail) {
4892 if (l.head.stats.nonEmpty()) {
4893 return true;
4894 }
4895 }
4896
4897 return false;
4898 }
4899 void checkSwitchCaseLabelDominated(JCCaseLabel unconditionalCaseLabel, List<JCCase> cases) {
4900 List<Pair<JCCase, JCCaseLabel>> caseLabels = List.nil();
4901 boolean seenDefault = false;
4902 boolean seenDefaultLabel = false;
4903 boolean warnDominatedByDefault = false;
4904 boolean unconditionalFound = false;
4905
4906 for (List<JCCase> l = cases; l.nonEmpty(); l = l.tail) {
4907 JCCase c = l.head;
4908 for (JCCaseLabel label : c.labels) {
4909 if (label.hasTag(DEFAULTCASELABEL)) {
4910 seenDefault = true;
4911 seenDefaultLabel |=
4912 TreeInfo.isNullCaseLabel(c.labels.head);
4913 continue;
4914 }
4915 if (TreeInfo.isNullCaseLabel(label)) {
4916 if (seenDefault) {
4917 log.error(label.pos(), Errors.PatternDominated);
4918 }
4919 continue;
4920 }
4921 if (seenDefault && !warnDominatedByDefault) {
4922 if (label.hasTag(PATTERNCASELABEL) ||
4923 (label instanceof JCConstantCaseLabel && seenDefaultLabel)) {
4924 log.error(label.pos(), Errors.PatternDominated);
4925 warnDominatedByDefault = true;
4926 }
4927 }
4928 Type currentType = labelType(label);
4929 for (Pair<JCCase, JCCaseLabel> caseAndLabel : caseLabels) {
4930 JCCase testCase = caseAndLabel.fst;
4931 JCCaseLabel testCaseLabel = caseAndLabel.snd;
4932 Type testType = labelType(testCaseLabel);
4933 boolean dominated = false;
4934 if (unconditionalCaseLabel == testCaseLabel) unconditionalFound = true;
4935 if (types.isUnconditionallyExact(currentType, testType) &&
4936 !currentType.hasTag(ERROR) && !testType.hasTag(ERROR)) {
4937 //the current label is potentially dominated by the existing (test) label, check:
4938 if (label instanceof JCConstantCaseLabel) {
4939 dominated |= !(testCaseLabel instanceof JCConstantCaseLabel) &&
4940 TreeInfo.unguardedCase(testCase);
4941 } else if (label instanceof JCPatternCaseLabel patternCL &&
4942 testCaseLabel instanceof JCPatternCaseLabel testPatternCaseLabel &&
4943 (testCase.equals(c) || TreeInfo.unguardedCase(testCase))) {
4944 dominated = patternDominated(testPatternCaseLabel.pat,
4945 patternCL.pat);
4946 }
4947 }
4948
4949 // Domination can occur even when we have not an unconditional pair between case labels.
4950 if (unconditionalFound && unconditionalCaseLabel != label) {
4951 dominated = true;
4952 }
4953
4954 if (dominated) {
4955 log.error(label.pos(), Errors.PatternDominated);
4956 }
4957 }
4958 caseLabels = caseLabels.prepend(Pair.of(c, label));
4959 }
4960 }
4961 }
4962 //where:
4963 private Type labelType(JCCaseLabel label) {
4964 return types.erasure(switch (label.getTag()) {
4965 case PATTERNCASELABEL -> ((JCPatternCaseLabel) label).pat.type;
4966 case CONSTANTCASELABEL -> ((JCConstantCaseLabel) label).expr.type;
4967 default -> throw Assert.error("Unexpected tree kind: " + label.getTag());
4968 });
4969 }
4970 private boolean patternDominated(JCPattern existingPattern, JCPattern currentPattern) {
4971 Type existingPatternType = types.erasure(existingPattern.type);
4972 Type currentPatternType = types.erasure(currentPattern.type);
4973 if (!types.isUnconditionallyExact(currentPatternType, existingPatternType)) {
4974 return false;
4975 }
4976 if (currentPattern instanceof JCBindingPattern ||
4977 currentPattern instanceof JCAnyPattern) {
4978 return existingPattern instanceof JCBindingPattern ||
4979 existingPattern instanceof JCAnyPattern;
4980 } else if (currentPattern instanceof JCRecordPattern currentRecordPattern) {
4981 if (existingPattern instanceof JCBindingPattern ||
4982 existingPattern instanceof JCAnyPattern) {
4983 return true;
4984 } else if (existingPattern instanceof JCRecordPattern existingRecordPattern) {
4985 List<JCPattern> existingNested = existingRecordPattern.nested;
4986 List<JCPattern> currentNested = currentRecordPattern.nested;
4987 if (existingNested.size() != currentNested.size()) {
4988 return false;
4989 }
4990 while (existingNested.nonEmpty()) {
4991 if (!patternDominated(existingNested.head, currentNested.head)) {
4992 return false;
4993 }
4994 existingNested = existingNested.tail;
4995 currentNested = currentNested.tail;
4996 }
4997 return true;
4998 } else {
4999 Assert.error("Unknown pattern: " + existingPattern.getTag());
5000 }
5001 } else {
5002 Assert.error("Unknown pattern: " + currentPattern.getTag());
5003 }
5004 return false;
5005 }
5006
5007 /** check if a type is a subtype of Externalizable, if that is available. */
5008 boolean isExternalizable(Type t) {
5009 try {
5010 syms.externalizableType.complete();
5011 } catch (CompletionFailure e) {
5012 return false;
5013 }
5014 return types.isSubtype(t, syms.externalizableType);
5015 }
5016
5017 /**
5018 * Check structure of serialization declarations.
5019 */
5020 public void checkSerialStructure(Env<AttrContext> env, JCClassDecl tree, ClassSymbol c) {
5021 (new SerialTypeVisitor(env)).visit(c, tree);
5022 }
5023
5024 /**
5025 * This visitor will warn if a serialization-related field or
5026 * method is declared in a suspicious or incorrect way. In
5027 * particular, it will warn for cases where the runtime
5028 * serialization mechanism will silently ignore a mis-declared
5029 * entity.
5030 *
5031 * Distinguished serialization-related fields and methods:
5032 *
5033 * Methods:
5034 *
5035 * private void writeObject(ObjectOutputStream stream) throws IOException
5036 * ANY-ACCESS-MODIFIER Object writeReplace() throws ObjectStreamException
5037 *
5038 * private void readObject(ObjectInputStream stream) throws IOException, ClassNotFoundException
5039 * private void readObjectNoData() throws ObjectStreamException
5040 * ANY-ACCESS-MODIFIER Object readResolve() throws ObjectStreamException
5041 *
5042 * Fields:
5043 *
5044 * private static final long serialVersionUID
5045 * private static final ObjectStreamField[] serialPersistentFields
5046 *
5047 * Externalizable: methods defined on the interface
5048 * public void writeExternal(ObjectOutput) throws IOException
5049 * public void readExternal(ObjectInput) throws IOException
5050 */
5051 private class SerialTypeVisitor extends ElementKindVisitor14<Void, JCClassDecl> {
5052 Env<AttrContext> env;
5053 SerialTypeVisitor(Env<AttrContext> env) {
5054 this.lint = Check.this.lint;
5055 this.env = env;
5056 }
5057
5058 private static final Set<String> serialMethodNames =
5059 Set.of("writeObject", "writeReplace",
5060 "readObject", "readObjectNoData",
5061 "readResolve");
5062
5063 private static final Set<String> serialFieldNames =
5064 Set.of("serialVersionUID", "serialPersistentFields");
5065
5066 // Type of serialPersistentFields
5067 private final Type OSF_TYPE = new Type.ArrayType(syms.objectStreamFieldType, syms.arrayClass);
5068
5069 Lint lint;
5070
5071 @Override
5072 public Void defaultAction(Element e, JCClassDecl p) {
5073 throw new IllegalArgumentException(Objects.requireNonNullElse(e.toString(), ""));
5074 }
5075
5076 @Override
5077 public Void visitType(TypeElement e, JCClassDecl p) {
5078 runUnderLint(e, p, (symbol, param) -> super.visitType(symbol, param));
5079 return null;
5080 }
5081
5082 @Override
5083 public Void visitTypeAsClass(TypeElement e,
5084 JCClassDecl p) {
5085 // Anonymous classes filtered out by caller.
5086
5087 ClassSymbol c = (ClassSymbol)e;
5088
5089 checkCtorAccess(p, c);
5090
5091 // Check for missing serialVersionUID; check *not* done
5092 // for enums or records.
5093 VarSymbol svuidSym = null;
5094 for (Symbol sym : c.members().getSymbolsByName(names.serialVersionUID)) {
5095 if (sym.kind == VAR) {
5096 svuidSym = (VarSymbol)sym;
5097 break;
5098 }
5099 }
5100
5101 if (svuidSym == null) {
5102 log.warning(LintCategory.SERIAL, p.pos(), Warnings.MissingSVUID(c));
5103 }
5104
5105 // Check for serialPersistentFields to gate checks for
5106 // non-serializable non-transient instance fields
5107 boolean serialPersistentFieldsPresent =
5108 c.members()
5109 .getSymbolsByName(names.serialPersistentFields, sym -> sym.kind == VAR)
5110 .iterator()
5111 .hasNext();
5112
5113 // Check declarations of serialization-related methods and
5114 // fields
5115 final boolean[] hasWriteReplace = {false};
5116 for(Symbol el : c.getEnclosedElements()) {
5117 runUnderLint(el, p, (enclosed, tree) -> {
5118 String name = null;
5119 switch(enclosed.getKind()) {
5120 case FIELD -> {
5121 if (!serialPersistentFieldsPresent) {
5122 var flags = enclosed.flags();
5123 if ( ((flags & TRANSIENT) == 0) &&
5124 ((flags & STATIC) == 0)) {
5125 Type varType = enclosed.asType();
5126 if (!canBeSerialized(varType)) {
5127 // Note per JLS arrays are
5128 // serializable even if the
5129 // component type is not.
5130 log.warning(LintCategory.SERIAL,
5131 TreeInfo.diagnosticPositionFor(enclosed, tree),
5132 Warnings.NonSerializableInstanceField);
5133 } else if (varType.hasTag(ARRAY)) {
5134 ArrayType arrayType = (ArrayType)varType;
5135 Type elementType = arrayType.elemtype;
5136 while (elementType.hasTag(ARRAY)) {
5137 arrayType = (ArrayType)elementType;
5138 elementType = arrayType.elemtype;
5139 }
5140 if (!canBeSerialized(elementType)) {
5141 log.warning(LintCategory.SERIAL,
5142 TreeInfo.diagnosticPositionFor(enclosed, tree),
5143 Warnings.NonSerializableInstanceFieldArray(elementType));
5144 }
5145 }
5146 }
5147 }
5148
5149 name = enclosed.getSimpleName().toString();
5150 if (serialFieldNames.contains(name)) {
5151 VarSymbol field = (VarSymbol)enclosed;
5152 switch (name) {
5153 case "serialVersionUID" -> checkSerialVersionUID(tree, e, field);
5154 case "serialPersistentFields" -> checkSerialPersistentFields(tree, e, field);
5155 default -> throw new AssertionError();
5156 }
5157 }
5158 }
5159
5160 // Correctly checking the serialization-related
5161 // methods is subtle. For the methods declared to be
5162 // private or directly declared in the class, the
5163 // enclosed elements of the class can be checked in
5164 // turn. However, writeReplace and readResolve can be
5165 // declared in a superclass and inherited. Note that
5166 // the runtime lookup walks the superclass chain
5167 // looking for writeReplace/readResolve via
5168 // Class.getDeclaredMethod. This differs from calling
5169 // Elements.getAllMembers(TypeElement) as the latter
5170 // will also pull in default methods from
5171 // superinterfaces. In other words, the runtime checks
5172 // (which long predate default methods on interfaces)
5173 // do not admit the possibility of inheriting methods
5174 // this way, a difference from general inheritance.
5175
5176 // The current implementation just checks the enclosed
5177 // elements and does not directly check the inherited
5178 // methods. If all the types are being checked this is
5179 // less of a concern; however, there are cases that
5180 // could be missed. In particular, readResolve and
5181 // writeReplace could, in principle, by inherited from
5182 // a non-serializable superclass and thus not checked
5183 // even if compiled with a serializable child class.
5184 case METHOD -> {
5185 var method = (MethodSymbol)enclosed;
5186 name = method.getSimpleName().toString();
5187 if (serialMethodNames.contains(name)) {
5188 switch (name) {
5189 case "writeObject" -> checkWriteObject(tree, e, method);
5190 case "writeReplace" -> {hasWriteReplace[0] = true; hasAppropriateWriteReplace(tree, method, true);}
5191 case "readObject" -> checkReadObject(tree,e, method);
5192 case "readObjectNoData" -> checkReadObjectNoData(tree, e, method);
5193 case "readResolve" -> checkReadResolve(tree, e, method);
5194 default -> throw new AssertionError();
5195 }
5196 }
5197 }
5198 }
5199 });
5200 }
5201 if (!hasWriteReplace[0] &&
5202 (c.isValueClass() || hasAbstractValueSuperClass(c, Set.of(syms.numberType.tsym))) &&
5203 !c.isAbstract() && !c.isRecord() &&
5204 types.unboxedType(c.type) == Type.noType) {
5205 // we need to check if the class is inheriting an appropriate writeReplace method
5206 MethodSymbol ms = null;
5207 Log.DiagnosticHandler discardHandler = new Log.DiscardDiagnosticHandler(log);
5208 try {
5209 ms = rs.resolveInternalMethod(env.tree, env, c.type, names.writeReplace, List.nil(), List.nil());
5210 } catch (FatalError fe) {
5211 // ignore no method was found
5212 } finally {
5213 log.popDiagnosticHandler(discardHandler);
5214 }
5215 if (ms == null || !hasAppropriateWriteReplace(p, ms, false)) {
5216 log.warning(LintCategory.SERIAL, p,
5217 c.isValueClass() ? Warnings.SerializableValueClassWithoutWriteReplace1 :
5218 Warnings.SerializableValueClassWithoutWriteReplace2);
5219 }
5220 }
5221 return null;
5222 }
5223
5224 boolean canBeSerialized(Type type) {
5225 return type.isPrimitive() || rs.isSerializable(type);
5226 }
5227
5228 private boolean hasAbstractValueSuperClass(Symbol c, Set<Symbol> excluding) {
5229 while (c.getKind() == ElementKind.CLASS) {
5230 Type sup = ((ClassSymbol)c).getSuperclass();
5231 if (!sup.hasTag(CLASS) || sup.isErroneous() ||
5232 sup.tsym == syms.objectType.tsym) {
5233 return false;
5234 }
5235 // if it is a value super class it has to be abstract
5236 if (sup.isValueClass() && !excluding.contains(sup.tsym)) {
5237 return true;
5238 }
5239 c = sup.tsym;
5240 }
5241 return false;
5242 }
5243
5244 /**
5245 * Check that Externalizable class needs a public no-arg
5246 * constructor.
5247 *
5248 * Check that a Serializable class has access to the no-arg
5249 * constructor of its first nonserializable superclass.
5250 */
5251 private void checkCtorAccess(JCClassDecl tree, ClassSymbol c) {
5252 if (isExternalizable(c.type)) {
5253 for(var sym : c.getEnclosedElements()) {
5254 if (sym.isConstructor() &&
5255 ((sym.flags() & PUBLIC) == PUBLIC)) {
5256 if (((MethodSymbol)sym).getParameters().isEmpty()) {
5257 return;
5258 }
5259 }
5260 }
5261 log.warning(LintCategory.SERIAL, tree.pos(),
5262 Warnings.ExternalizableMissingPublicNoArgCtor);
5263 } else {
5264 // Approximate access to the no-arg constructor up in
5265 // the superclass chain by checking that the
5266 // constructor is not private. This may not handle
5267 // some cross-package situations correctly.
5268 Type superClass = c.getSuperclass();
5269 // java.lang.Object is *not* Serializable so this loop
5270 // should terminate.
5271 while (rs.isSerializable(superClass) ) {
5272 try {
5273 superClass = (Type)((TypeElement)(((DeclaredType)superClass)).asElement()).getSuperclass();
5274 } catch(ClassCastException cce) {
5275 return ; // Don't try to recover
5276 }
5277 }
5278 // Non-Serializable superclass
5279 try {
5280 ClassSymbol supertype = ((ClassSymbol)(((DeclaredType)superClass).asElement()));
5281 for(var sym : supertype.getEnclosedElements()) {
5282 if (sym.isConstructor()) {
5283 MethodSymbol ctor = (MethodSymbol)sym;
5284 if (ctor.getParameters().isEmpty()) {
5285 if (((ctor.flags() & PRIVATE) == PRIVATE) ||
5286 // Handle nested classes and implicit this$0
5287 (supertype.getNestingKind() == NestingKind.MEMBER &&
5288 ((supertype.flags() & STATIC) == 0)))
5289 log.warning(LintCategory.SERIAL, tree.pos(),
5290 Warnings.SerializableMissingAccessNoArgCtor(supertype.getQualifiedName()));
5291 }
5292 }
5293 }
5294 } catch (ClassCastException cce) {
5295 return ; // Don't try to recover
5296 }
5297 return;
5298 }
5299 }
5300
5301 private void checkSerialVersionUID(JCClassDecl tree, Element e, VarSymbol svuid) {
5302 // To be effective, serialVersionUID must be marked static
5303 // and final, but private is recommended. But alas, in
5304 // practice there are many non-private serialVersionUID
5305 // fields.
5306 if ((svuid.flags() & (STATIC | FINAL)) !=
5307 (STATIC | FINAL)) {
5308 log.warning(LintCategory.SERIAL,
5309 TreeInfo.diagnosticPositionFor(svuid, tree),
5310 Warnings.ImproperSVUID((Symbol)e));
5311 }
5312
5313 // check svuid has type long
5314 if (!svuid.type.hasTag(LONG)) {
5315 log.warning(LintCategory.SERIAL,
5316 TreeInfo.diagnosticPositionFor(svuid, tree),
5317 Warnings.LongSVUID((Symbol)e));
5318 }
5319
5320 if (svuid.getConstValue() == null)
5321 log.warning(LintCategory.SERIAL,
5322 TreeInfo.diagnosticPositionFor(svuid, tree),
5323 Warnings.ConstantSVUID((Symbol)e));
5324 }
5325
5326 private void checkSerialPersistentFields(JCClassDecl tree, Element e, VarSymbol spf) {
5327 // To be effective, serialPersisentFields must be private, static, and final.
5328 if ((spf.flags() & (PRIVATE | STATIC | FINAL)) !=
5329 (PRIVATE | STATIC | FINAL)) {
5330 log.warning(LintCategory.SERIAL,
5331 TreeInfo.diagnosticPositionFor(spf, tree),
5332 Warnings.ImproperSPF);
5333 }
5334
5335 if (!types.isSameType(spf.type, OSF_TYPE)) {
5336 log.warning(LintCategory.SERIAL,
5337 TreeInfo.diagnosticPositionFor(spf, tree),
5338 Warnings.OSFArraySPF);
5339 }
5340
5341 if (isExternalizable((Type)(e.asType()))) {
5342 log.warning(LintCategory.SERIAL,
5343 TreeInfo.diagnosticPositionFor(spf, tree),
5344 Warnings.IneffectualSerialFieldExternalizable);
5345 }
5346
5347 // Warn if serialPersistentFields is initialized to a
5348 // literal null.
5349 JCTree spfDecl = TreeInfo.declarationFor(spf, tree);
5350 if (spfDecl != null && spfDecl.getTag() == VARDEF) {
5351 JCVariableDecl variableDef = (JCVariableDecl) spfDecl;
5352 JCExpression initExpr = variableDef.init;
5353 if (initExpr != null && TreeInfo.isNull(initExpr)) {
5354 log.warning(LintCategory.SERIAL, initExpr.pos(),
5355 Warnings.SPFNullInit);
5356 }
5357 }
5358 }
5359
5360 private void checkWriteObject(JCClassDecl tree, Element e, MethodSymbol method) {
5361 // The "synchronized" modifier is seen in the wild on
5362 // readObject and writeObject methods and is generally
5363 // innocuous.
5364
5365 // private void writeObject(ObjectOutputStream stream) throws IOException
5366 checkPrivateNonStaticMethod(tree, method);
5367 isExpectedReturnType(tree, method, syms.voidType, true);
5368 checkOneArg(tree, e, method, syms.objectOutputStreamType);
5369 hasExpectedExceptions(tree, method, true, syms.ioExceptionType);
5370 checkExternalizable(tree, e, method);
5371 }
5372
5373 private boolean hasAppropriateWriteReplace(JCClassDecl tree, MethodSymbol method, boolean warn) {
5374 // ANY-ACCESS-MODIFIER Object writeReplace() throws
5375 // ObjectStreamException
5376
5377 // Excluding abstract, could have a more complicated
5378 // rule based on abstract-ness of the class
5379 return isConcreteInstanceMethod(tree, method, warn) &&
5380 isExpectedReturnType(tree, method, syms.objectType, warn) &&
5381 hasNoArgs(tree, method, warn) &&
5382 hasExpectedExceptions(tree, method, warn, syms.objectStreamExceptionType);
5383 }
5384
5385 private void checkReadObject(JCClassDecl tree, Element e, MethodSymbol method) {
5386 // The "synchronized" modifier is seen in the wild on
5387 // readObject and writeObject methods and is generally
5388 // innocuous.
5389
5390 // private void readObject(ObjectInputStream stream)
5391 // throws IOException, ClassNotFoundException
5392 checkPrivateNonStaticMethod(tree, method);
5393 isExpectedReturnType(tree, method, syms.voidType, true);
5394 checkOneArg(tree, e, method, syms.objectInputStreamType);
5395 hasExpectedExceptions(tree, method, true, syms.ioExceptionType, syms.classNotFoundExceptionType);
5396 checkExternalizable(tree, e, method);
5397 }
5398
5399 private void checkReadObjectNoData(JCClassDecl tree, Element e, MethodSymbol method) {
5400 // private void readObjectNoData() throws ObjectStreamException
5401 checkPrivateNonStaticMethod(tree, method);
5402 isExpectedReturnType(tree, method, syms.voidType, true);
5403 hasNoArgs(tree, method, true);
5404 hasExpectedExceptions(tree, method, true, syms.objectStreamExceptionType);
5405 checkExternalizable(tree, e, method);
5406 }
5407
5408 private void checkReadResolve(JCClassDecl tree, Element e, MethodSymbol method) {
5409 // ANY-ACCESS-MODIFIER Object readResolve()
5410 // throws ObjectStreamException
5411
5412 // Excluding abstract, could have a more complicated
5413 // rule based on abstract-ness of the class
5414 isConcreteInstanceMethod(tree, method, true);
5415 isExpectedReturnType(tree, method, syms.objectType, true);
5416 hasNoArgs(tree, method, true);
5417 hasExpectedExceptions(tree, method, true, syms.objectStreamExceptionType);
5418 }
5419
5420 private void checkWriteExternalRecord(JCClassDecl tree, Element e, MethodSymbol method, boolean isExtern) {
5421 //public void writeExternal(ObjectOutput) throws IOException
5422 checkExternMethodRecord(tree, e, method, syms.objectOutputType, isExtern);
5423 }
5424
5425 private void checkReadExternalRecord(JCClassDecl tree, Element e, MethodSymbol method, boolean isExtern) {
5426 // public void readExternal(ObjectInput) throws IOException
5427 checkExternMethodRecord(tree, e, method, syms.objectInputType, isExtern);
5428 }
5429
5430 private void checkExternMethodRecord(JCClassDecl tree, Element e, MethodSymbol method, Type argType,
5431 boolean isExtern) {
5432 if (isExtern && isExternMethod(tree, e, method, argType)) {
5433 log.warning(LintCategory.SERIAL,
5434 TreeInfo.diagnosticPositionFor(method, tree),
5435 Warnings.IneffectualExternalizableMethodRecord(method.getSimpleName().toString()));
5436 }
5437 }
5438
5439 void checkPrivateNonStaticMethod(JCClassDecl tree, MethodSymbol method) {
5440 var flags = method.flags();
5441 if ((flags & PRIVATE) == 0) {
5442 log.warning(LintCategory.SERIAL,
5443 TreeInfo.diagnosticPositionFor(method, tree),
5444 Warnings.SerialMethodNotPrivate(method.getSimpleName()));
5445 }
5446
5447 if ((flags & STATIC) != 0) {
5448 log.warning(LintCategory.SERIAL,
5449 TreeInfo.diagnosticPositionFor(method, tree),
5450 Warnings.SerialMethodStatic(method.getSimpleName()));
5451 }
5452 }
5453
5454 /**
5455 * Per section 1.12 "Serialization of Enum Constants" of
5456 * the serialization specification, due to the special
5457 * serialization handling of enums, any writeObject,
5458 * readObject, writeReplace, and readResolve methods are
5459 * ignored as are serialPersistentFields and
5460 * serialVersionUID fields.
5461 */
5462 @Override
5463 public Void visitTypeAsEnum(TypeElement e,
5464 JCClassDecl p) {
5465 boolean isExtern = isExternalizable((Type)e.asType());
5466 for(Element el : e.getEnclosedElements()) {
5467 runUnderLint(el, p, (enclosed, tree) -> {
5468 String name = enclosed.getSimpleName().toString();
5469 switch(enclosed.getKind()) {
5470 case FIELD -> {
5471 var field = (VarSymbol)enclosed;
5472 if (serialFieldNames.contains(name)) {
5473 log.warning(LintCategory.SERIAL,
5474 TreeInfo.diagnosticPositionFor(field, tree),
5475 Warnings.IneffectualSerialFieldEnum(name));
5476 }
5477 }
5478
5479 case METHOD -> {
5480 var method = (MethodSymbol)enclosed;
5481 if (serialMethodNames.contains(name)) {
5482 log.warning(LintCategory.SERIAL,
5483 TreeInfo.diagnosticPositionFor(method, tree),
5484 Warnings.IneffectualSerialMethodEnum(name));
5485 }
5486
5487 if (isExtern) {
5488 switch(name) {
5489 case "writeExternal" -> checkWriteExternalEnum(tree, e, method);
5490 case "readExternal" -> checkReadExternalEnum(tree, e, method);
5491 }
5492 }
5493 }
5494
5495 // Also perform checks on any class bodies of enum constants, see JLS 8.9.1.
5496 case ENUM_CONSTANT -> {
5497 var field = (VarSymbol)enclosed;
5498 JCVariableDecl decl = (JCVariableDecl) TreeInfo.declarationFor(field, p);
5499 if (decl.init instanceof JCNewClass nc && nc.def != null) {
5500 ClassSymbol enumConstantType = nc.def.sym;
5501 visitTypeAsEnum(enumConstantType, p);
5502 }
5503 }
5504
5505 }});
5506 }
5507 return null;
5508 }
5509
5510 private void checkWriteExternalEnum(JCClassDecl tree, Element e, MethodSymbol method) {
5511 //public void writeExternal(ObjectOutput) throws IOException
5512 checkExternMethodEnum(tree, e, method, syms.objectOutputType);
5513 }
5514
5515 private void checkReadExternalEnum(JCClassDecl tree, Element e, MethodSymbol method) {
5516 // public void readExternal(ObjectInput) throws IOException
5517 checkExternMethodEnum(tree, e, method, syms.objectInputType);
5518 }
5519
5520 private void checkExternMethodEnum(JCClassDecl tree, Element e, MethodSymbol method, Type argType) {
5521 if (isExternMethod(tree, e, method, argType)) {
5522 log.warning(LintCategory.SERIAL,
5523 TreeInfo.diagnosticPositionFor(method, tree),
5524 Warnings.IneffectualExternMethodEnum(method.getSimpleName().toString()));
5525 }
5526 }
5527
5528 private boolean isExternMethod(JCClassDecl tree, Element e, MethodSymbol method, Type argType) {
5529 long flags = method.flags();
5530 Type rtype = method.getReturnType();
5531
5532 // Not necessary to check throws clause in this context
5533 return (flags & PUBLIC) != 0 && (flags & STATIC) == 0 &&
5534 types.isSameType(syms.voidType, rtype) &&
5535 hasExactlyOneArgWithType(tree, e, method, argType);
5536 }
5537
5538 /**
5539 * Most serialization-related fields and methods on interfaces
5540 * are ineffectual or problematic.
5541 */
5542 @Override
5543 public Void visitTypeAsInterface(TypeElement e,
5544 JCClassDecl p) {
5545 for(Element el : e.getEnclosedElements()) {
5546 runUnderLint(el, p, (enclosed, tree) -> {
5547 String name = null;
5548 switch(enclosed.getKind()) {
5549 case FIELD -> {
5550 var field = (VarSymbol)enclosed;
5551 name = field.getSimpleName().toString();
5552 switch(name) {
5553 case "serialPersistentFields" -> {
5554 log.warning(LintCategory.SERIAL,
5555 TreeInfo.diagnosticPositionFor(field, tree),
5556 Warnings.IneffectualSerialFieldInterface);
5557 }
5558
5559 case "serialVersionUID" -> {
5560 checkSerialVersionUID(tree, e, field);
5561 }
5562 }
5563 }
5564
5565 case METHOD -> {
5566 var method = (MethodSymbol)enclosed;
5567 name = enclosed.getSimpleName().toString();
5568 if (serialMethodNames.contains(name)) {
5569 switch (name) {
5570 case
5571 "readObject",
5572 "readObjectNoData",
5573 "writeObject" -> checkPrivateMethod(tree, e, method);
5574
5575 case
5576 "writeReplace",
5577 "readResolve" -> checkDefaultIneffective(tree, e, method);
5578
5579 default -> throw new AssertionError();
5580 }
5581
5582 }
5583 }}
5584 });
5585 }
5586
5587 return null;
5588 }
5589
5590 private void checkPrivateMethod(JCClassDecl tree,
5591 Element e,
5592 MethodSymbol method) {
5593 if ((method.flags() & PRIVATE) == 0) {
5594 log.warning(LintCategory.SERIAL,
5595 TreeInfo.diagnosticPositionFor(method, tree),
5596 Warnings.NonPrivateMethodWeakerAccess);
5597 }
5598 }
5599
5600 private void checkDefaultIneffective(JCClassDecl tree,
5601 Element e,
5602 MethodSymbol method) {
5603 if ((method.flags() & DEFAULT) == DEFAULT) {
5604 log.warning(LintCategory.SERIAL,
5605 TreeInfo.diagnosticPositionFor(method, tree),
5606 Warnings.DefaultIneffective);
5607
5608 }
5609 }
5610
5611 @Override
5612 public Void visitTypeAsAnnotationType(TypeElement e,
5613 JCClassDecl p) {
5614 // Per the JLS, annotation types are not serializeable
5615 return null;
5616 }
5617
5618 /**
5619 * From the Java Object Serialization Specification, 1.13
5620 * Serialization of Records:
5621 *
5622 * "The process by which record objects are serialized or
5623 * externalized cannot be customized; any class-specific
5624 * writeObject, readObject, readObjectNoData, writeExternal,
5625 * and readExternal methods defined by record classes are
5626 * ignored during serialization and deserialization. However,
5627 * a substitute object to be serialized or a designate
5628 * replacement may be specified, by the writeReplace and
5629 * readResolve methods, respectively. Any
5630 * serialPersistentFields field declaration is
5631 * ignored. Documenting serializable fields and data for
5632 * record classes is unnecessary, since there is no variation
5633 * in the serial form, other than whether a substitute or
5634 * replacement object is used. The serialVersionUID of a
5635 * record class is 0L unless explicitly declared. The
5636 * requirement for matching serialVersionUID values is waived
5637 * for record classes."
5638 */
5639 @Override
5640 public Void visitTypeAsRecord(TypeElement e,
5641 JCClassDecl p) {
5642 boolean isExtern = isExternalizable((Type)e.asType());
5643 for(Element el : e.getEnclosedElements()) {
5644 runUnderLint(el, p, (enclosed, tree) -> {
5645 String name = enclosed.getSimpleName().toString();
5646 switch(enclosed.getKind()) {
5647 case FIELD -> {
5648 var field = (VarSymbol)enclosed;
5649 switch(name) {
5650 case "serialPersistentFields" -> {
5651 log.warning(LintCategory.SERIAL,
5652 TreeInfo.diagnosticPositionFor(field, tree),
5653 Warnings.IneffectualSerialFieldRecord);
5654 }
5655
5656 case "serialVersionUID" -> {
5657 // Could generate additional warning that
5658 // svuid value is not checked to match for
5659 // records.
5660 checkSerialVersionUID(tree, e, field);
5661 }}
5662 }
5663
5664 case METHOD -> {
5665 var method = (MethodSymbol)enclosed;
5666 switch(name) {
5667 case "writeReplace" -> hasAppropriateWriteReplace(tree, method, true);
5668 case "readResolve" -> checkReadResolve(tree, e, method);
5669
5670 case "writeExternal" -> checkWriteExternalRecord(tree, e, method, isExtern);
5671 case "readExternal" -> checkReadExternalRecord(tree, e, method, isExtern);
5672
5673 default -> {
5674 if (serialMethodNames.contains(name)) {
5675 log.warning(LintCategory.SERIAL,
5676 TreeInfo.diagnosticPositionFor(method, tree),
5677 Warnings.IneffectualSerialMethodRecord(name));
5678 }
5679 }}
5680 }}});
5681 }
5682 return null;
5683 }
5684
5685 boolean isConcreteInstanceMethod(JCClassDecl tree,
5686 MethodSymbol method,
5687 boolean warn) {
5688 if ((method.flags() & (STATIC | ABSTRACT)) != 0) {
5689 if (warn) {
5690 log.warning(LintCategory.SERIAL,
5691 TreeInfo.diagnosticPositionFor(method, tree),
5692 Warnings.SerialConcreteInstanceMethod(method.getSimpleName()));
5693 }
5694 return false;
5695 }
5696 return true;
5697 }
5698
5699 private boolean isExpectedReturnType(JCClassDecl tree,
5700 MethodSymbol method,
5701 Type expectedReturnType,
5702 boolean warn) {
5703 // Note: there may be complications checking writeReplace
5704 // and readResolve since they return Object and could, in
5705 // principle, have covariant overrides and any synthetic
5706 // bridge method would not be represented here for
5707 // checking.
5708 Type rtype = method.getReturnType();
5709 if (!types.isSameType(expectedReturnType, rtype)) {
5710 if (warn) {
5711 log.warning(LintCategory.SERIAL,
5712 TreeInfo.diagnosticPositionFor(method, tree),
5713 Warnings.SerialMethodUnexpectedReturnType(method.getSimpleName(),
5714 rtype, expectedReturnType));
5715 }
5716 return false;
5717 }
5718 return true;
5719 }
5720
5721 private void checkOneArg(JCClassDecl tree,
5722 Element enclosing,
5723 MethodSymbol method,
5724 Type expectedType) {
5725 String name = method.getSimpleName().toString();
5726
5727 var parameters= method.getParameters();
5728
5729 if (parameters.size() != 1) {
5730 log.warning(LintCategory.SERIAL,
5731 TreeInfo.diagnosticPositionFor(method, tree),
5732 Warnings.SerialMethodOneArg(method.getSimpleName(), parameters.size()));
5733 return;
5734 }
5735
5736 Type parameterType = parameters.get(0).asType();
5737 if (!types.isSameType(parameterType, expectedType)) {
5738 log.warning(LintCategory.SERIAL,
5739 TreeInfo.diagnosticPositionFor(method, tree),
5740 Warnings.SerialMethodParameterType(method.getSimpleName(),
5741 expectedType,
5742 parameterType));
5743 }
5744 }
5745
5746 private boolean hasExactlyOneArgWithType(JCClassDecl tree,
5747 Element enclosing,
5748 MethodSymbol method,
5749 Type expectedType) {
5750 var parameters = method.getParameters();
5751 return (parameters.size() == 1) &&
5752 types.isSameType(parameters.get(0).asType(), expectedType);
5753 }
5754
5755
5756 boolean hasNoArgs(JCClassDecl tree, MethodSymbol method, boolean warn) {
5757 var parameters = method.getParameters();
5758 if (!parameters.isEmpty()) {
5759 if (warn) {
5760 log.warning(LintCategory.SERIAL,
5761 TreeInfo.diagnosticPositionFor(parameters.get(0), tree),
5762 Warnings.SerialMethodNoArgs(method.getSimpleName()));
5763 }
5764 return false;
5765 }
5766 return true;
5767 }
5768
5769 private void checkExternalizable(JCClassDecl tree, Element enclosing, MethodSymbol method) {
5770 // If the enclosing class is externalizable, warn for the method
5771 if (isExternalizable((Type)enclosing.asType())) {
5772 log.warning(LintCategory.SERIAL,
5773 TreeInfo.diagnosticPositionFor(method, tree),
5774 Warnings.IneffectualSerialMethodExternalizable(method.getSimpleName()));
5775 }
5776 return;
5777 }
5778
5779 private boolean hasExpectedExceptions(JCClassDecl tree,
5780 MethodSymbol method,
5781 boolean warn,
5782 Type... declaredExceptions) {
5783 for (Type thrownType: method.getThrownTypes()) {
5784 // For each exception in the throws clause of the
5785 // method, if not an Error and not a RuntimeException,
5786 // check if the exception is a subtype of a declared
5787 // exception from the throws clause of the
5788 // serialization method in question.
5789 if (types.isSubtype(thrownType, syms.runtimeExceptionType) ||
5790 types.isSubtype(thrownType, syms.errorType) ) {
5791 continue;
5792 } else {
5793 boolean declared = false;
5794 for (Type declaredException : declaredExceptions) {
5795 if (types.isSubtype(thrownType, declaredException)) {
5796 declared = true;
5797 continue;
5798 }
5799 }
5800 if (!declared) {
5801 if (warn) {
5802 log.warning(LintCategory.SERIAL,
5803 TreeInfo.diagnosticPositionFor(method, tree),
5804 Warnings.SerialMethodUnexpectedException(method.getSimpleName(),
5805 thrownType));
5806 }
5807 return false;
5808 }
5809 }
5810 }
5811 return true;
5812 }
5813
5814 private <E extends Element> Void runUnderLint(E symbol, JCClassDecl p, BiConsumer<E, JCClassDecl> task) {
5815 Lint prevLint = lint;
5816 try {
5817 lint = lint.augment((Symbol) symbol);
5818
5819 if (lint.isEnabled(LintCategory.SERIAL)) {
5820 task.accept(symbol, p);
5821 }
5822
5823 return null;
5824 } finally {
5825 lint = prevLint;
5826 }
5827 }
5828
5829 }
5830
5831 }
--- EOF ---