1 /*
2 * Copyright (c) 1999, 2026, 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;
50 import com.sun.tools.javac.resources.CompilerProperties.Errors;
51 import com.sun.tools.javac.resources.CompilerProperties.Fragments;
52 import com.sun.tools.javac.resources.CompilerProperties.Warnings;
53 import com.sun.tools.javac.resources.CompilerProperties.LintWarnings;
54 import com.sun.tools.javac.tree.*;
55 import com.sun.tools.javac.util.*;
56 import com.sun.tools.javac.util.JCDiagnostic.DiagnosticFlag;
57 import com.sun.tools.javac.util.JCDiagnostic.DiagnosticPosition;
58 import com.sun.tools.javac.util.JCDiagnostic.Error;
59 import com.sun.tools.javac.util.JCDiagnostic.Fragment;
60 import com.sun.tools.javac.util.JCDiagnostic.LintWarning;
61 import com.sun.tools.javac.util.List;
62
63 import com.sun.tools.javac.code.Lint;
64 import com.sun.tools.javac.code.Lint.LintCategory;
65 import com.sun.tools.javac.code.Scope.WriteableScope;
66 import com.sun.tools.javac.code.Type.*;
67 import com.sun.tools.javac.code.Symbol.*;
68 import com.sun.tools.javac.comp.DeferredAttr.DeferredAttrContext;
69 import com.sun.tools.javac.tree.JCTree.*;
70
71 import static com.sun.tools.javac.code.Flags.*;
72 import static com.sun.tools.javac.code.Flags.ANNOTATION;
73 import static com.sun.tools.javac.code.Flags.SYNCHRONIZED;
74 import static com.sun.tools.javac.code.Kinds.*;
75 import static com.sun.tools.javac.code.Kinds.Kind.*;
76 import static com.sun.tools.javac.code.Scope.LookupKind.NON_RECURSIVE;
77 import static com.sun.tools.javac.code.Scope.LookupKind.RECURSIVE;
78 import static com.sun.tools.javac.code.TypeTag.*;
79 import static com.sun.tools.javac.code.TypeTag.WILDCARD;
80
81 import static com.sun.tools.javac.tree.JCTree.Tag.*;
82 import javax.lang.model.element.Element;
83 import javax.lang.model.element.TypeElement;
84 import javax.lang.model.type.DeclaredType;
85 import javax.lang.model.util.ElementKindVisitor14;
86
87 /** Type checking helper class for the attribution phase.
88 *
89 * <p><b>This is NOT part of any supported API.
90 * If you write code that depends on this, you do so at your own risk.
91 * This code and its internal interfaces are subject to change or
92 * deletion without notice.</b>
93 */
94 public class Check {
95 protected static final Context.Key<Check> checkKey = new Context.Key<>();
96
97 // Flag bits indicating which item(s) chosen from a pair of items
98 private static final int FIRST = 0x01;
99 private static final int SECOND = 0x02;
100
101 private final Names names;
102 private final Log log;
103 private final Resolve rs;
104 private final Symtab syms;
105 private final Enter enter;
106 private final DeferredAttr deferredAttr;
107 private final Infer infer;
108 private final Types types;
109 private final TypeAnnotations typeAnnotations;
110 private final JCDiagnostic.Factory diags;
111 private final JavaFileManager fileManager;
112 private final Source source;
113 private final Target target;
114 private final Profile profile;
115 private final Preview preview;
116 private final boolean warnOnAnyAccessToMembers;
117
118 public boolean disablePreviewCheck;
119
120 // The set of lint options currently in effect. It is initialized
121 // from the context, and then is set/reset as needed by Attr as it
122 // visits all the various parts of the trees during attribution.
123 private Lint lint;
124
125 // The method being analyzed in Attr - it is set/reset as needed by
126 // Attr as it visits new method declarations.
127 private MethodSymbol method;
128
129 public static Check instance(Context context) {
130 Check instance = context.get(checkKey);
131 if (instance == null)
132 instance = new Check(context);
133 return instance;
134 }
135
136 @SuppressWarnings("this-escape")
137 protected Check(Context context) {
138 context.put(checkKey, this);
139
140 names = Names.instance(context);
141 log = Log.instance(context);
142 rs = Resolve.instance(context);
143 syms = Symtab.instance(context);
144 enter = Enter.instance(context);
145 deferredAttr = DeferredAttr.instance(context);
146 infer = Infer.instance(context);
147 types = Types.instance(context);
148 typeAnnotations = TypeAnnotations.instance(context);
149 diags = JCDiagnostic.Factory.instance(context);
150 Options options = Options.instance(context);
151 lint = Lint.instance(context);
152 fileManager = context.get(JavaFileManager.class);
153
154 source = Source.instance(context);
155 target = Target.instance(context);
156 warnOnAnyAccessToMembers = options.isSet("warnOnAccessToMembers");
157
158 disablePreviewCheck = false;
159
160 Target target = Target.instance(context);
161 syntheticNameChar = target.syntheticNameChar();
162
163 profile = Profile.instance(context);
164 preview = Preview.instance(context);
165
166 allowModules = Feature.MODULES.allowedInSource(source);
167 allowRecords = Feature.RECORDS.allowedInSource(source);
168 allowSealed = Feature.SEALED_CLASSES.allowedInSource(source);
169 allowPrimitivePatterns = preview.isEnabled() && Feature.PRIMITIVE_PATTERNS.allowedInSource(source);
170 allowValueClasses = preview.isEnabled() && Feature.VALUE_CLASSES.allowedInSource(source);
171 }
172
173 /** Character for synthetic names
174 */
175 char syntheticNameChar;
176
177 /** A table mapping flat names of all compiled classes for each module in this run
178 * to their symbols; maintained from outside.
179 */
180 private Map<Pair<ModuleSymbol, Name>,ClassSymbol> compiled = new HashMap<>();
181
182 /** Are modules allowed
183 */
184 private final boolean allowModules;
185
186 /** Are records allowed
187 */
188 private final boolean allowRecords;
189
190 /** Are sealed classes allowed
191 */
192 private final boolean allowSealed;
193
194 /** Are primitive patterns allowed
195 */
196 private final boolean allowPrimitivePatterns;
197
198 /** Are value classes allowed
199 */
200 private final boolean allowValueClasses;
201
202 /** Whether to force suppression of deprecation and preview warnings.
203 * This happens when attributing import statements for JDK 9+.
204 * @see Feature#DEPRECATION_ON_IMPORT
205 */
206 private boolean importSuppression;
207
208 /* *************************************************************************
209 * Errors and Warnings
210 **************************************************************************/
211
212 Lint setLint(Lint newLint) {
213 Lint prev = lint;
214 lint = newLint;
215 return prev;
216 }
217
218 boolean setImportSuppression(boolean newImportSuppression) {
219 boolean prev = importSuppression;
220 importSuppression = newImportSuppression;
221 return prev;
222 }
223
224 MethodSymbol setMethod(MethodSymbol newMethod) {
225 MethodSymbol prev = method;
226 method = newMethod;
227 return prev;
228 }
229
230 /** Warn about deprecated symbol.
231 * @param pos Position to be used for error reporting.
232 * @param sym The deprecated symbol.
233 */
234 void warnDeprecated(DiagnosticPosition pos, Symbol sym) {
235 Assert.check(!importSuppression);
236 LintWarning warningKey = sym.isDeprecatedForRemoval() ?
237 (sym.kind == MDL ?
238 LintWarnings.HasBeenDeprecatedForRemovalModule(sym) :
239 LintWarnings.HasBeenDeprecatedForRemoval(sym, sym.location())) :
240 (sym.kind == MDL ?
241 LintWarnings.HasBeenDeprecatedModule(sym) :
242 LintWarnings.HasBeenDeprecated(sym, sym.location()));
243 log.warning(pos, warningKey);
244 }
245
246 /** Log a preview warning.
247 * @param pos Position to be used for error reporting.
248 * @param msg A Warning describing the problem.
249 */
250 public void warnPreviewAPI(DiagnosticPosition pos, LintWarning warnKey) {
251 if (!importSuppression)
252 log.warning(pos, warnKey);
253 }
254
255 /** Warn about unchecked operation.
256 * @param pos Position to be used for error reporting.
257 * @param msg A string describing the problem.
258 */
259 public void warnUnchecked(DiagnosticPosition pos, LintWarning warnKey) {
260 log.warning(pos, warnKey);
261 }
262
263 /** Report a failure to complete a class.
264 * @param pos Position to be used for error reporting.
265 * @param ex The failure to report.
266 */
267 public Type completionError(DiagnosticPosition pos, CompletionFailure ex) {
268 log.error(DiagnosticFlag.NON_DEFERRABLE, pos, Errors.CantAccess(ex.sym, ex.getDetailValue()));
269 return syms.errType;
270 }
271
272 /** Report an error that wrong type tag was found.
273 * @param pos Position to be used for error reporting.
274 * @param required An internationalized string describing the type tag
275 * required.
276 * @param type The type that was found.
277 */
278 Type typeTagError(DiagnosticPosition pos, JCDiagnostic required, Type type) {
279 // this error used to be raised by the parser,
280 // but has been delayed to this point:
281 if (type.hasTag(VOID)) {
282 log.error(pos, Errors.IllegalStartOfType);
283 return syms.errType;
284 }
285 log.error(pos, Errors.TypeFoundReq(asTypeParam(type), required));
286 return types.createErrorType(type);
287 }
288
289 /** Report duplicate declaration error.
290 */
291 void duplicateError(DiagnosticPosition pos, Symbol sym) {
292 if (!sym.type.isErroneous()) {
293 Symbol location = sym.location();
294 if (location.kind == MTH &&
295 ((MethodSymbol)location).isStaticOrInstanceInit()) {
296 log.error(pos,
297 Errors.AlreadyDefinedInClinit(kindName(sym),
298 sym,
299 kindName(sym.location()),
300 kindName(sym.location().enclClass()),
301 sym.location().enclClass()));
302 } else {
303 /* dont error if this is a duplicated parameter of a generated canonical constructor
304 * as we should have issued an error for the duplicated fields
305 */
306 if (location.kind != MTH ||
307 ((sym.owner.flags_field & GENERATEDCONSTR) == 0) ||
308 ((sym.owner.flags_field & RECORD) == 0)) {
309 log.error(pos,
310 Errors.AlreadyDefined(kindName(sym),
311 sym,
312 kindName(sym.location()),
313 sym.location()));
314 }
315 }
316 }
317 }
318
319 /** Report array/varargs duplicate declaration
320 */
321 void varargsDuplicateError(DiagnosticPosition pos, Symbol sym1, Symbol sym2) {
322 if (!sym1.type.isErroneous() && !sym2.type.isErroneous()) {
323 log.error(pos, Errors.ArrayAndVarargs(sym1, sym2, sym2.location()));
324 }
325 }
326
327 /* ************************************************************************
328 * duplicate declaration checking
329 *************************************************************************/
330
331 /** Check that variable does not hide variable with same name in
332 * immediately enclosing local scope.
333 * @param pos Position for error reporting.
334 * @param v The symbol.
335 * @param s The scope.
336 */
337 void checkTransparentVar(DiagnosticPosition pos, VarSymbol v, Scope s) {
338 for (Symbol sym : s.getSymbolsByName(v.name)) {
339 if (sym.owner != v.owner) break;
340 if (sym.kind == VAR &&
341 sym.owner.kind.matches(KindSelector.VAL_MTH) &&
342 v.name != names.error) {
343 duplicateError(pos, sym);
344 return;
345 }
346 }
347 }
348
349 /** Check that a class or interface does not hide a class or
350 * interface with same name in immediately enclosing local scope.
351 * @param pos Position for error reporting.
352 * @param c The symbol.
353 * @param s The scope.
354 */
355 void checkTransparentClass(DiagnosticPosition pos, ClassSymbol c, Scope s) {
356 for (Symbol sym : s.getSymbolsByName(c.name)) {
357 if (sym.owner != c.owner) break;
358 if (sym.kind == TYP && !sym.type.hasTag(TYPEVAR) &&
359 sym.owner.kind.matches(KindSelector.VAL_MTH) &&
360 c.name != names.error) {
361 duplicateError(pos, sym);
362 return;
363 }
364 }
365 }
366
367 /** Check that class does not have the same name as one of
368 * its enclosing classes, or as a class defined in its enclosing scope.
369 * return true if class is unique in its enclosing scope.
370 * @param pos Position for error reporting.
371 * @param name The class name.
372 * @param s The enclosing scope.
373 */
374 boolean checkUniqueClassName(DiagnosticPosition pos, Name name, Scope s) {
375 for (Symbol sym : s.getSymbolsByName(name, NON_RECURSIVE)) {
376 if (sym.kind == TYP && sym.name != names.error) {
377 duplicateError(pos, sym);
378 return false;
379 }
380 }
381 for (Symbol sym = s.owner; sym != null; sym = sym.owner) {
382 if (sym.kind == TYP && sym.name == name && sym.name != names.error &&
383 !sym.isImplicit()) {
384 duplicateError(pos, sym);
385 return true;
386 }
387 }
388 return true;
389 }
390
391 /* *************************************************************************
392 * Class name generation
393 **************************************************************************/
394
395
396 private Map<Pair<Name, Name>, Integer> localClassNameIndexes = new HashMap<>();
397
398 /** Return name of local class.
399 * This is of the form {@code <enclClass> $ n <classname> }
400 * where
401 * enclClass is the flat name of the enclosing class,
402 * classname is the simple name of the local class
403 */
404 public Name localClassName(ClassSymbol c) {
405 Name enclFlatname = c.owner.enclClass().flatname;
406 String enclFlatnameStr = enclFlatname.toString();
407 Pair<Name, Name> key = new Pair<>(enclFlatname, c.name);
408 Integer index = localClassNameIndexes.get(key);
409 for (int i = (index == null) ? 1 : index; ; i++) {
410 Name flatname = names.fromString(enclFlatnameStr
411 + syntheticNameChar + i + c.name);
412 if (getCompiled(c.packge().modle, flatname) == null) {
413 localClassNameIndexes.put(key, i + 1);
414 return flatname;
415 }
416 }
417 }
418
419 public void clearLocalClassNameIndexes(ClassSymbol c) {
420 if (c.owner != null && c.owner.kind != NIL) {
421 localClassNameIndexes.remove(new Pair<>(
422 c.owner.enclClass().flatname, c.name));
423 }
424 }
425
426 public void newRound() {
427 compiled.clear();
428 localClassNameIndexes.clear();
429 }
430
431 public void putCompiled(ClassSymbol csym) {
432 compiled.put(Pair.of(csym.packge().modle, csym.flatname), csym);
433 }
434
435 public ClassSymbol getCompiled(ClassSymbol csym) {
436 return compiled.get(Pair.of(csym.packge().modle, csym.flatname));
437 }
438
439 public ClassSymbol getCompiled(ModuleSymbol msym, Name flatname) {
440 return compiled.get(Pair.of(msym, flatname));
441 }
442
443 public void removeCompiled(ClassSymbol csym) {
444 compiled.remove(Pair.of(csym.packge().modle, csym.flatname));
445 }
446
447 /* *************************************************************************
448 * Type Checking
449 **************************************************************************/
450
451 /**
452 * A check context is an object that can be used to perform compatibility
453 * checks - depending on the check context, meaning of 'compatibility' might
454 * vary significantly.
455 */
456 public interface CheckContext {
457 /**
458 * Is type 'found' compatible with type 'req' in given context
459 */
460 boolean compatible(Type found, Type req, Warner warn);
461 /**
462 * Report a check error
463 */
464 void report(DiagnosticPosition pos, JCDiagnostic details);
465 /**
466 * Obtain a warner for this check context
467 */
468 public Warner checkWarner(DiagnosticPosition pos, Type found, Type req);
469
470 public InferenceContext inferenceContext();
471
472 public DeferredAttr.DeferredAttrContext deferredAttrContext();
473 }
474
475 /**
476 * This class represent a check context that is nested within another check
477 * context - useful to check sub-expressions. The default behavior simply
478 * redirects all method calls to the enclosing check context leveraging
479 * the forwarding pattern.
480 */
481 static class NestedCheckContext implements CheckContext {
482 CheckContext enclosingContext;
483
484 NestedCheckContext(CheckContext enclosingContext) {
485 this.enclosingContext = enclosingContext;
486 }
487
488 public boolean compatible(Type found, Type req, Warner warn) {
489 return enclosingContext.compatible(found, req, warn);
490 }
491
492 public void report(DiagnosticPosition pos, JCDiagnostic details) {
493 enclosingContext.report(pos, details);
494 }
495
496 public Warner checkWarner(DiagnosticPosition pos, Type found, Type req) {
497 return enclosingContext.checkWarner(pos, found, req);
498 }
499
500 public InferenceContext inferenceContext() {
501 return enclosingContext.inferenceContext();
502 }
503
504 public DeferredAttrContext deferredAttrContext() {
505 return enclosingContext.deferredAttrContext();
506 }
507 }
508
509 /**
510 * Check context to be used when evaluating assignment/return statements
511 */
512 CheckContext basicHandler = new CheckContext() {
513 public void report(DiagnosticPosition pos, JCDiagnostic details) {
514 log.error(pos, Errors.ProbFoundReq(details));
515 }
516 public boolean compatible(Type found, Type req, Warner warn) {
517 return types.isAssignable(found, req, warn);
518 }
519
520 public Warner checkWarner(DiagnosticPosition pos, Type found, Type req) {
521 return convertWarner(pos, found, req);
522 }
523
524 public InferenceContext inferenceContext() {
525 return infer.emptyContext;
526 }
527
528 public DeferredAttrContext deferredAttrContext() {
529 return deferredAttr.emptyDeferredAttrContext;
530 }
531
532 @Override
533 public String toString() {
534 return "CheckContext: basicHandler";
535 }
536 };
537
538 /** Check that a given type is assignable to a given proto-type.
539 * If it is, return the type, otherwise return errType.
540 * @param pos Position to be used for error reporting.
541 * @param found The type that was found.
542 * @param req The type that was required.
543 */
544 public Type checkType(DiagnosticPosition pos, Type found, Type req) {
545 return checkType(pos, found, req, basicHandler);
546 }
547
548 Type checkType(final DiagnosticPosition pos, final Type found, final Type req, final CheckContext checkContext) {
549 final InferenceContext inferenceContext = checkContext.inferenceContext();
550 if (inferenceContext.free(req) || inferenceContext.free(found)) {
551 inferenceContext.addFreeTypeListener(List.of(req, found),
552 solvedContext -> checkType(pos, solvedContext.asInstType(found), solvedContext.asInstType(req), checkContext));
553 }
554 if (req.hasTag(ERROR))
555 return req;
556 if (req.hasTag(NONE))
557 return found;
558 if (checkContext.compatible(found, req, checkContext.checkWarner(pos, found, req))) {
559 return found;
560 } else {
561 if (found.isNumeric() && req.isNumeric()) {
562 checkContext.report(pos, diags.fragment(Fragments.PossibleLossOfPrecision(found, req)));
563 return types.createErrorType(found);
564 }
565 checkContext.report(pos, diags.fragment(Fragments.InconvertibleTypes(found, req)));
566 return types.createErrorType(found);
567 }
568 }
569
570 /** Check that a given type can be cast to a given target type.
571 * Return the result of the cast.
572 * @param pos Position to be used for error reporting.
573 * @param found The type that is being cast.
574 * @param req The target type of the cast.
575 */
576 Type checkCastable(DiagnosticPosition pos, Type found, Type req) {
577 return checkCastable(pos, found, req, basicHandler);
578 }
579 Type checkCastable(DiagnosticPosition pos, Type found, Type req, CheckContext checkContext) {
580 if (types.isCastable(found, req, castWarner(pos, found, req))) {
581 return req;
582 } else {
583 checkContext.report(pos, diags.fragment(Fragments.InconvertibleTypes(found, req)));
584 return types.createErrorType(found);
585 }
586 }
587
588 /** Check for redundant casts (i.e. where source type is a subtype of target type)
589 * The problem should only be reported for non-292 cast
590 */
591 public void checkRedundantCast(Env<AttrContext> env, final JCTypeCast tree) {
592 if (!tree.type.isErroneous()
593 && types.isSameType(tree.expr.type, tree.clazz.type)
594 && !(ignoreAnnotatedCasts && TreeInfo.containsTypeAnnotation(tree.clazz))
595 && !is292targetTypeCast(tree)) {
596 log.warning(tree.pos(), LintWarnings.RedundantCast(tree.clazz.type));
597 }
598 }
599 //where
600 private boolean is292targetTypeCast(JCTypeCast tree) {
601 boolean is292targetTypeCast = false;
602 JCExpression expr = TreeInfo.skipParens(tree.expr);
603 if (expr.hasTag(APPLY)) {
604 JCMethodInvocation apply = (JCMethodInvocation)expr;
605 Symbol sym = TreeInfo.symbol(apply.meth);
606 is292targetTypeCast = sym != null &&
607 sym.kind == MTH &&
608 (sym.flags() & HYPOTHETICAL) != 0;
609 }
610 return is292targetTypeCast;
611 }
612
613 private static final boolean ignoreAnnotatedCasts = true;
614
615 /** Check that a type is within some bounds.
616 *
617 * Used in TypeApply to verify that, e.g., X in {@code V<X>} is a valid
618 * type argument.
619 * @param a The type that should be bounded by bs.
620 * @param bound The bound.
621 */
622 private boolean checkExtends(Type a, Type bound) {
623 if (a.isUnbound()) {
624 return true;
625 } else if (!a.hasTag(WILDCARD)) {
626 a = types.cvarUpperBound(a);
627 return types.isSubtype(a, bound);
628 } else if (a.isExtendsBound()) {
629 return types.isCastable(bound, types.wildUpperBound(a), types.noWarnings);
630 } else if (a.isSuperBound()) {
631 return !types.notSoftSubtype(types.wildLowerBound(a), bound);
632 }
633 return true;
634 }
635
636 /** Check that type is different from 'void'.
637 * @param pos Position to be used for error reporting.
638 * @param t The type to be checked.
639 */
640 Type checkNonVoid(DiagnosticPosition pos, Type t) {
641 if (t.hasTag(VOID)) {
642 log.error(pos, Errors.VoidNotAllowedHere);
643 return types.createErrorType(t);
644 } else {
645 return t;
646 }
647 }
648
649 Type checkClassOrArrayType(DiagnosticPosition pos, Type t) {
650 if (!t.hasTag(CLASS) && !t.hasTag(ARRAY) && !t.hasTag(ERROR)) {
651 return typeTagError(pos,
652 diags.fragment(Fragments.TypeReqClassArray),
653 t);
654 } else {
655 return t;
656 }
657 }
658
659 /** Check that type is a class or interface type.
660 * @param pos Position to be used for error reporting.
661 * @param t The type to be checked.
662 */
663 Type checkClassType(DiagnosticPosition pos, Type t) {
664 if (!t.hasTag(CLASS) && !t.hasTag(ERROR)) {
665 return typeTagError(pos,
666 diags.fragment(Fragments.TypeReqClass),
667 t);
668 } else {
669 return t;
670 }
671 }
672 //where
673 private Object asTypeParam(Type t) {
674 return (t.hasTag(TYPEVAR))
675 ? diags.fragment(Fragments.TypeParameter(t))
676 : t;
677 }
678
679 /** Check that type is a valid qualifier for a constructor reference expression
680 */
681 Type checkConstructorRefType(DiagnosticPosition pos, Type t) {
682 t = checkClassOrArrayType(pos, t);
683 if (t.hasTag(CLASS)) {
684 if ((t.tsym.flags() & (ABSTRACT | INTERFACE)) != 0) {
685 log.error(pos, Errors.AbstractCantBeInstantiated(t.tsym));
686 t = types.createErrorType(t);
687 } else if ((t.tsym.flags() & ENUM) != 0) {
688 log.error(pos, Errors.EnumCantBeInstantiated);
689 t = types.createErrorType(t);
690 } else {
691 t = checkClassType(pos, t, true);
692 }
693 } else if (t.hasTag(ARRAY)) {
694 if (!types.isReifiable(((ArrayType)t).elemtype)) {
695 log.error(pos, Errors.GenericArrayCreation);
696 t = types.createErrorType(t);
697 }
698 }
699 return t;
700 }
701
702 /** Check that type is a class or interface type.
703 * @param pos Position to be used for error reporting.
704 * @param t The type to be checked.
705 * @param noBounds True if type bounds are illegal here.
706 */
707 Type checkClassType(DiagnosticPosition pos, Type t, boolean noBounds) {
708 t = checkClassType(pos, t);
709 if (noBounds && t.isParameterized()) {
710 List<Type> args = t.getTypeArguments();
711 while (args.nonEmpty()) {
712 if (args.head.hasTag(WILDCARD))
713 return typeTagError(pos,
714 diags.fragment(Fragments.TypeReqExact),
715 args.head);
716 args = args.tail;
717 }
718 }
719 return t;
720 }
721
722 /** Check that type is a reference type, i.e. a class, interface or array type
723 * or a type variable.
724 * @param pos Position to be used for error reporting.
725 * @param t The type to be checked.
726 */
727 Type checkRefType(DiagnosticPosition pos, Type t) {
728 if (t.isReference())
729 return t;
730 else
731 return typeTagError(pos,
732 diags.fragment(Fragments.TypeReqRef),
733 t);
734 }
735
736 /** Check that type is an identity type, i.e. not a value type.
737 * When not discernible statically, give it the benefit of doubt
738 * and defer to runtime.
739 *
740 * @param pos Position to be used for error reporting.
741 * @param t The type to be checked.
742 */
743 boolean checkIdentityType(DiagnosticPosition pos, Type t) {
744 if (t.hasTag(TYPEVAR)) {
745 t = types.skipTypeVars(t, false);
746 }
747 if (t.isIntersection()) {
748 IntersectionClassType ict = (IntersectionClassType)t;
749 boolean result = true;
750 for (Type component : ict.getExplicitComponents()) {
751 result &= checkIdentityType(pos, component);
752 }
753 return result;
754 }
755 if (t.isPrimitive() || (t.isValueClass() && !t.tsym.isAbstract())) {
756 typeTagError(pos, diags.fragment(Fragments.TypeReqIdentity), t);
757 return false;
758 }
759 return true;
760 }
761
762 /** Check that each type is a reference type, i.e. a class, interface or array type
763 * or a type variable.
764 * @param trees Original trees, used for error reporting.
765 * @param types The types to be checked.
766 */
767 List<Type> checkRefTypes(List<JCExpression> trees, List<Type> types) {
768 List<JCExpression> tl = trees;
769 for (List<Type> l = types; l.nonEmpty(); l = l.tail) {
770 l.head = checkRefType(tl.head.pos(), l.head);
771 tl = tl.tail;
772 }
773 return types;
774 }
775
776 /** Check that type is a null or reference type.
777 * @param pos Position to be used for error reporting.
778 * @param t The type to be checked.
779 */
780 Type checkNullOrRefType(DiagnosticPosition pos, Type t) {
781 if (t.isReference() || t.hasTag(BOT))
782 return t;
783 else
784 return typeTagError(pos,
785 diags.fragment(Fragments.TypeReqRef),
786 t);
787 }
788
789 /** Check that flag set does not contain elements of two conflicting sets. s
790 * Return true if it doesn't.
791 * @param pos Position to be used for error reporting.
792 * @param flags The set of flags to be checked.
793 * @param set1 Conflicting flags set #1.
794 * @param set2 Conflicting flags set #2.
795 */
796 boolean checkDisjoint(DiagnosticPosition pos, long flags, long set1, long set2) {
797 if ((flags & set1) != 0 && (flags & set2) != 0) {
798 log.error(pos,
799 Errors.IllegalCombinationOfModifiers(asFlagSet(TreeInfo.firstFlag(flags & set1)),
800 asFlagSet(TreeInfo.firstFlag(flags & set2))));
801 return false;
802 } else
803 return true;
804 }
805
806 /** Check that usage of diamond operator is correct (i.e. diamond should not
807 * be used with non-generic classes or in anonymous class creation expressions)
808 */
809 Type checkDiamond(JCNewClass tree, Type t) {
810 if (!TreeInfo.isDiamond(tree) ||
811 t.isErroneous()) {
812 return checkClassType(tree.clazz.pos(), t, true);
813 } else {
814 if (tree.def != null && !Feature.DIAMOND_WITH_ANONYMOUS_CLASS_CREATION.allowedInSource(source)) {
815 log.error(DiagnosticFlag.SOURCE_LEVEL, tree.clazz.pos(),
816 Errors.CantApplyDiamond1(t, Feature.DIAMOND_WITH_ANONYMOUS_CLASS_CREATION.fragment(source.name)));
817 }
818 if (t.tsym.type.getTypeArguments().isEmpty()) {
819 log.error(tree.clazz.pos(),
820 Errors.CantApplyDiamond1(t,
821 Fragments.DiamondNonGeneric(t)));
822 return types.createErrorType(t);
823 } else if (tree.typeargs != null &&
824 tree.typeargs.nonEmpty()) {
825 log.error(tree.clazz.pos(),
826 Errors.CantApplyDiamond1(t,
827 Fragments.DiamondAndExplicitParams(t)));
828 return types.createErrorType(t);
829 } else {
830 return t;
831 }
832 }
833 }
834
835 /** Check that the type inferred using the diamond operator does not contain
836 * non-denotable types such as captured types or intersection types.
837 * @param t the type inferred using the diamond operator
838 * @return the (possibly empty) list of non-denotable types.
839 */
840 List<Type> checkDiamondDenotable(ClassType t) {
841 ListBuffer<Type> buf = new ListBuffer<>();
842 for (Type arg : t.allparams()) {
843 if (!checkDenotable(arg)) {
844 buf.append(arg);
845 }
846 }
847 return buf.toList();
848 }
849
850 public boolean checkDenotable(Type t) {
851 return denotableChecker.visit(t, null);
852 }
853 // where
854
855 /** diamondTypeChecker: A type visitor that descends down the given type looking for non-denotable
856 * types. The visit methods return false as soon as a non-denotable type is encountered and true
857 * otherwise.
858 */
859 private static final Types.SimpleVisitor<Boolean, Void> denotableChecker = new Types.SimpleVisitor<Boolean, Void>() {
860 @Override
861 public Boolean visitType(Type t, Void s) {
862 return true;
863 }
864 @Override
865 public Boolean visitClassType(ClassType t, Void s) {
866 if (t.isUnion() || t.isIntersection()) {
867 return false;
868 }
869 for (Type targ : t.allparams()) {
870 if (!visit(targ, s)) {
871 return false;
872 }
873 }
874 return true;
875 }
876
877 @Override
878 public Boolean visitTypeVar(TypeVar t, Void s) {
879 /* Any type variable mentioned in the inferred type must have been declared as a type parameter
880 (i.e cannot have been produced by inference (18.4))
881 */
882 return (t.tsym.flags() & SYNTHETIC) == 0;
883 }
884
885 @Override
886 public Boolean visitCapturedType(CapturedType t, Void s) {
887 /* Any type variable mentioned in the inferred type must have been declared as a type parameter
888 (i.e cannot have been produced by capture conversion (5.1.10))
889 */
890 return false;
891 }
892
893 @Override
894 public Boolean visitArrayType(ArrayType t, Void s) {
895 return visit(t.elemtype, s);
896 }
897
898 @Override
899 public Boolean visitWildcardType(WildcardType t, Void s) {
900 return visit(t.type, s);
901 }
902 };
903
904 void checkVarargsMethodDecl(Env<AttrContext> env, JCMethodDecl tree) {
905 MethodSymbol m = tree.sym;
906 boolean hasTrustMeAnno = m.attribute(syms.trustMeType.tsym) != null;
907 Type varargElemType = null;
908 if (m.isVarArgs()) {
909 varargElemType = types.elemtype(tree.params.last().type);
910 }
911 if (hasTrustMeAnno && !isTrustMeAllowedOnMethod(m)) {
912 if (varargElemType != null) {
913 JCDiagnostic msg = Feature.PRIVATE_SAFE_VARARGS.allowedInSource(source) ?
914 diags.fragment(Fragments.VarargsTrustmeOnVirtualVarargs(m)) :
915 diags.fragment(Fragments.VarargsTrustmeOnVirtualVarargsFinalOnly(m));
916 log.error(tree,
917 Errors.VarargsInvalidTrustmeAnno(syms.trustMeType.tsym,
918 msg));
919 } else {
920 log.error(tree,
921 Errors.VarargsInvalidTrustmeAnno(syms.trustMeType.tsym,
922 Fragments.VarargsTrustmeOnNonVarargsMeth(m)));
923 }
924 } else if (hasTrustMeAnno && varargElemType != null &&
925 types.isReifiable(varargElemType)) {
926 log.warning(tree.pos(), LintWarnings.VarargsRedundantTrustmeAnno(
927 syms.trustMeType.tsym,
928 diags.fragment(Fragments.VarargsTrustmeOnReifiableVarargs(varargElemType))));
929 }
930 else if (!hasTrustMeAnno && varargElemType != null &&
931 !types.isReifiable(varargElemType)) {
932 warnUnchecked(tree.params.last().pos(), LintWarnings.UncheckedVarargsNonReifiableType(varargElemType));
933 }
934 }
935 //where
936 private boolean isTrustMeAllowedOnMethod(Symbol s) {
937 return (s.flags() & VARARGS) != 0 &&
938 (s.isConstructor() ||
939 (s.flags() & (STATIC | FINAL |
940 (Feature.PRIVATE_SAFE_VARARGS.allowedInSource(source) ? PRIVATE : 0) )) != 0);
941 }
942
943 Type checkLocalVarType(DiagnosticPosition pos, Type t, Name name) {
944 //check that resulting type is not the null type
945 if (t.hasTag(BOT)) {
946 log.error(pos, Errors.CantInferLocalVarType(name, Fragments.LocalCantInferNull));
947 return types.createErrorType(t);
948 } else if (t.hasTag(VOID)) {
949 log.error(pos, Errors.CantInferLocalVarType(name, Fragments.LocalCantInferVoid));
950 return types.createErrorType(t);
951 }
952
953 //upward project the initializer type
954 return types.upward(t, types.captures(t)).baseType();
955 }
956
957 Type checkMethod(final Type mtype,
958 final Symbol sym,
959 final Env<AttrContext> env,
960 final List<JCExpression> argtrees,
961 final List<Type> argtypes,
962 final boolean useVarargs,
963 InferenceContext inferenceContext) {
964 // System.out.println("call : " + env.tree);
965 // System.out.println("method : " + owntype);
966 // System.out.println("actuals: " + argtypes);
967 if (inferenceContext.free(mtype)) {
968 inferenceContext.addFreeTypeListener(List.of(mtype),
969 solvedContext -> checkMethod(solvedContext.asInstType(mtype), sym, env, argtrees, argtypes, useVarargs, solvedContext));
970 return mtype;
971 }
972 Type owntype = mtype;
973 List<Type> formals = owntype.getParameterTypes();
974 List<Type> nonInferred = sym.type.getParameterTypes();
975 if (nonInferred.length() != formals.length()) nonInferred = formals;
976 Type last = useVarargs ? formals.last() : null;
977 if (sym.name == names.init && sym.owner == syms.enumSym) {
978 formals = formals.tail.tail;
979 nonInferred = nonInferred.tail.tail;
980 }
981 if ((sym.flags() & ANONCONSTR_BASED) != 0) {
982 formals = formals.tail;
983 nonInferred = nonInferred.tail;
984 }
985 List<JCExpression> args = argtrees;
986 if (args != null) {
987 //this is null when type-checking a method reference
988 while (formals.head != last) {
989 JCTree arg = args.head;
990 Warner warn = convertWarner(arg.pos(), arg.type, nonInferred.head);
991 assertConvertible(arg, arg.type, formals.head, warn);
992 args = args.tail;
993 formals = formals.tail;
994 nonInferred = nonInferred.tail;
995 }
996 if (useVarargs) {
997 Type varArg = types.elemtype(last);
998 while (args.tail != null) {
999 JCTree arg = args.head;
1000 Warner warn = convertWarner(arg.pos(), arg.type, varArg);
1001 assertConvertible(arg, arg.type, varArg, warn);
1002 args = args.tail;
1003 }
1004 } else if ((sym.flags() & (VARARGS | SIGNATURE_POLYMORPHIC)) == VARARGS) {
1005 // non-varargs call to varargs method
1006 Type varParam = owntype.getParameterTypes().last();
1007 Type lastArg = argtypes.last();
1008 if (types.isSubtypeUnchecked(lastArg, types.elemtype(varParam)) &&
1009 !types.isSameType(types.erasure(varParam), types.erasure(lastArg)))
1010 log.warning(argtrees.last().pos(),
1011 Warnings.InexactNonVarargsCall(types.elemtype(varParam),varParam));
1012 }
1013 }
1014 if (useVarargs) {
1015 Type argtype = owntype.getParameterTypes().last();
1016 if (!types.isReifiable(argtype) &&
1017 (sym.baseSymbol().attribute(syms.trustMeType.tsym) == null ||
1018 !isTrustMeAllowedOnMethod(sym))) {
1019 warnUnchecked(env.tree.pos(), LintWarnings.UncheckedGenericArrayCreation(argtype));
1020 }
1021 TreeInfo.setVarargsElement(env.tree, types.elemtype(argtype));
1022 }
1023 return owntype;
1024 }
1025 //where
1026 private void assertConvertible(JCTree tree, Type actual, Type formal, Warner warn) {
1027 if (types.isConvertible(actual, formal, warn))
1028 return;
1029
1030 if (formal.isCompound()
1031 && types.isSubtype(actual, types.supertype(formal))
1032 && types.isSubtypeUnchecked(actual, types.interfaces(formal), warn))
1033 return;
1034 }
1035
1036 /**
1037 * Check that type 't' is a valid instantiation of a generic class
1038 * (see JLS 4.5)
1039 *
1040 * @param t class type to be checked
1041 * @return true if 't' is well-formed
1042 */
1043 public boolean checkValidGenericType(Type t) {
1044 return firstIncompatibleTypeArg(t) == null;
1045 }
1046 //WHERE
1047 private Type firstIncompatibleTypeArg(Type type) {
1048 List<Type> formals = type.tsym.type.allparams();
1049 List<Type> actuals = type.allparams();
1050 List<Type> args = type.getTypeArguments();
1051 List<Type> forms = type.tsym.type.getTypeArguments();
1052 ListBuffer<Type> bounds_buf = new ListBuffer<>();
1053
1054 // For matching pairs of actual argument types `a' and
1055 // formal type parameters with declared bound `b' ...
1056 while (args.nonEmpty() && forms.nonEmpty()) {
1057 // exact type arguments needs to know their
1058 // bounds (for upper and lower bound
1059 // calculations). So we create new bounds where
1060 // type-parameters are replaced with actuals argument types.
1061 bounds_buf.append(types.subst(forms.head.getUpperBound(), formals, actuals));
1062 args = args.tail;
1063 forms = forms.tail;
1064 }
1065
1066 args = type.getTypeArguments();
1067 List<Type> tvars_cap = types.substBounds(formals,
1068 formals,
1069 types.capture(type).allparams());
1070 while (args.nonEmpty() && tvars_cap.nonEmpty()) {
1071 // Let the actual arguments know their bound
1072 args.head.withTypeVar((TypeVar)tvars_cap.head);
1073 args = args.tail;
1074 tvars_cap = tvars_cap.tail;
1075 }
1076
1077 args = type.getTypeArguments();
1078 List<Type> bounds = bounds_buf.toList();
1079
1080 while (args.nonEmpty() && bounds.nonEmpty()) {
1081 Type actual = args.head;
1082 if (!isTypeArgErroneous(actual) &&
1083 !bounds.head.isErroneous() &&
1084 !checkExtends(actual, bounds.head)) {
1085 return args.head;
1086 }
1087 args = args.tail;
1088 bounds = bounds.tail;
1089 }
1090
1091 args = type.getTypeArguments();
1092 bounds = bounds_buf.toList();
1093
1094 for (Type arg : types.capture(type).getTypeArguments()) {
1095 if (arg.hasTag(TYPEVAR) &&
1096 arg.getUpperBound().isErroneous() &&
1097 !bounds.head.isErroneous() &&
1098 !isTypeArgErroneous(args.head)) {
1099 return args.head;
1100 }
1101 bounds = bounds.tail;
1102 args = args.tail;
1103 }
1104
1105 return null;
1106 }
1107 //where
1108 boolean isTypeArgErroneous(Type t) {
1109 return isTypeArgErroneous.visit(t);
1110 }
1111
1112 Types.UnaryVisitor<Boolean> isTypeArgErroneous = new Types.UnaryVisitor<Boolean>() {
1113 public Boolean visitType(Type t, Void s) {
1114 return t.isErroneous();
1115 }
1116 @Override
1117 public Boolean visitTypeVar(TypeVar t, Void s) {
1118 return visit(t.getUpperBound());
1119 }
1120 @Override
1121 public Boolean visitCapturedType(CapturedType t, Void s) {
1122 return visit(t.getUpperBound()) ||
1123 visit(t.getLowerBound());
1124 }
1125 @Override
1126 public Boolean visitWildcardType(WildcardType t, Void s) {
1127 return visit(t.type);
1128 }
1129 };
1130
1131 /** Check that given modifiers are legal for given symbol and
1132 * return modifiers together with any implicit modifiers for that symbol.
1133 * Warning: we can't use flags() here since this method
1134 * is called during class enter, when flags() would cause a premature
1135 * completion.
1136 * @param flags The set of modifiers given in a definition.
1137 * @param sym The defined symbol.
1138 * @param tree The declaration
1139 */
1140 long checkFlags(long flags, Symbol sym, JCTree tree) {
1141 final DiagnosticPosition pos = tree.pos();
1142 long mask;
1143 long implicit = 0;
1144
1145 switch (sym.kind) {
1146 case VAR:
1147 if (TreeInfo.isReceiverParam(tree))
1148 mask = ReceiverParamFlags;
1149 else if (sym.owner.kind != TYP)
1150 mask = LocalVarFlags;
1151 else if ((sym.owner.flags_field & INTERFACE) != 0)
1152 mask = implicit = InterfaceVarFlags;
1153 else {
1154 boolean isInstanceField = (flags & STATIC) == 0;
1155 boolean isInstanceFieldOfValueClass = isInstanceField && sym.owner.type.isValueClass();
1156 boolean isRecordField = isInstanceField && (sym.owner.flags_field & RECORD) != 0;
1157 if (allowValueClasses && (isInstanceFieldOfValueClass || isRecordField)) {
1158 implicit |= FINAL | STRICT;
1159 mask = ValueFieldFlags;
1160 } else {
1161 mask = VarFlags;
1162 }
1163 }
1164 break;
1165 case MTH:
1166 if (sym.name == names.init) {
1167 if ((sym.owner.flags_field & ENUM) != 0) {
1168 // enum constructors cannot be declared public or
1169 // protected and must be implicitly or explicitly
1170 // private
1171 implicit = PRIVATE;
1172 mask = PRIVATE;
1173 } else
1174 mask = ConstructorFlags;
1175 } else if ((sym.owner.flags_field & INTERFACE) != 0) {
1176 if ((sym.owner.flags_field & ANNOTATION) != 0) {
1177 mask = AnnotationTypeElementMask;
1178 implicit = PUBLIC | ABSTRACT;
1179 } else if ((flags & (DEFAULT | STATIC | PRIVATE)) != 0) {
1180 mask = InterfaceMethodMask;
1181 implicit = (flags & PRIVATE) != 0 ? 0 : PUBLIC;
1182 if ((flags & DEFAULT) != 0) {
1183 implicit |= ABSTRACT;
1184 }
1185 } else {
1186 mask = implicit = InterfaceMethodFlags;
1187 }
1188 } else if ((sym.owner.flags_field & RECORD) != 0) {
1189 mask = ((sym.owner.flags_field & VALUE_CLASS) != 0 && (flags & Flags.STATIC) == 0) ?
1190 RecordMethodFlags & ~SYNCHRONIZED : RecordMethodFlags;
1191 } else {
1192 // value objects do not have an associated monitor/lock
1193 mask = ((sym.owner.flags_field & VALUE_CLASS) != 0 && (flags & Flags.STATIC) == 0) ?
1194 MethodFlags & ~SYNCHRONIZED : MethodFlags;
1195 }
1196 if ((flags & STRICTFP) != 0) {
1197 log.warning(tree.pos(), LintWarnings.Strictfp);
1198 }
1199 // Imply STRICTFP if owner has STRICTFP set.
1200 if (((flags|implicit) & Flags.ABSTRACT) == 0 ||
1201 ((flags) & Flags.DEFAULT) != 0)
1202 implicit |= sym.owner.flags_field & STRICTFP;
1203 break;
1204 case TYP:
1205 if (sym.owner.kind.matches(KindSelector.VAL_MTH) ||
1206 (sym.isDirectlyOrIndirectlyLocal() && (flags & ANNOTATION) != 0)) {
1207 boolean implicitlyStatic = !sym.isAnonymous() &&
1208 ((flags & RECORD) != 0 || (flags & ENUM) != 0 || (flags & INTERFACE) != 0);
1209 boolean staticOrImplicitlyStatic = (flags & STATIC) != 0 || implicitlyStatic;
1210 // local statics are allowed only if records are allowed too
1211 mask = staticOrImplicitlyStatic && allowRecords && (flags & ANNOTATION) == 0 ? ExtendedStaticLocalClassFlags : ExtendedLocalClassFlags;
1212 implicit = implicitlyStatic ? STATIC : implicit;
1213 } else if (sym.owner.kind == TYP) {
1214 // statics in inner classes are allowed only if records are allowed too
1215 mask = ((flags & STATIC) != 0) && allowRecords && (flags & ANNOTATION) == 0 ? ExtendedMemberStaticClassFlags : ExtendedMemberClassFlags;
1216 if (sym.owner.owner.kind == PCK ||
1217 (sym.owner.flags_field & STATIC) != 0) {
1218 mask |= STATIC;
1219 } else if (!allowRecords && ((flags & ENUM) != 0 || (flags & RECORD) != 0)) {
1220 log.error(pos, Errors.StaticDeclarationNotAllowedInInnerClasses);
1221 }
1222 // Nested interfaces and enums are always STATIC (Spec ???)
1223 if ((flags & (INTERFACE | ENUM | RECORD)) != 0 ) implicit = STATIC;
1224 } else {
1225 mask = ExtendedClassFlags;
1226 }
1227 if ((flags & (VALUE_CLASS | SEALED | ABSTRACT)) == (VALUE_CLASS | SEALED) ||
1228 (flags & (VALUE_CLASS | NON_SEALED | ABSTRACT)) == (VALUE_CLASS | NON_SEALED)) {
1229 log.error(pos, Errors.NonAbstractValueClassCantBeSealedOrNonSealed);
1230 }
1231 // Interfaces are always ABSTRACT
1232 if ((flags & INTERFACE) != 0) implicit |= ABSTRACT;
1233
1234 if ((flags & (INTERFACE | VALUE_CLASS)) == 0) {
1235 implicit |= IDENTITY_TYPE;
1236 }
1237
1238 if ((flags & ENUM) != 0) {
1239 // enums can't be declared abstract, final, sealed or non-sealed or value
1240 mask &= ~(ABSTRACT | FINAL | SEALED | NON_SEALED | VALUE_CLASS);
1241 implicit |= implicitEnumFinalFlag(tree);
1242 }
1243 if ((flags & RECORD) != 0) {
1244 // records can't be declared abstract
1245 mask &= ~ABSTRACT;
1246 implicit |= FINAL;
1247 }
1248 if ((flags & STRICTFP) != 0) {
1249 log.warning(tree.pos(), LintWarnings.Strictfp);
1250 }
1251 // Imply STRICTFP if owner has STRICTFP set.
1252 implicit |= sym.owner.flags_field & STRICTFP;
1253
1254 // concrete value classes are implicitly final
1255 if ((flags & (ABSTRACT | INTERFACE | VALUE_CLASS)) == VALUE_CLASS) {
1256 implicit |= FINAL;
1257 }
1258 break;
1259 default:
1260 throw new AssertionError();
1261 }
1262 long illegal = flags & ExtendedStandardFlags & ~mask;
1263 if (illegal != 0) {
1264 if ((illegal & INTERFACE) != 0) {
1265 log.error(pos, ((flags & ANNOTATION) != 0) ? Errors.AnnotationDeclNotAllowedHere : Errors.IntfNotAllowedHere);
1266 mask |= INTERFACE;
1267 }
1268 else {
1269 log.error(pos,
1270 Errors.ModNotAllowedHere(asFlagSet(illegal)));
1271 }
1272 } else if ((sym.kind == TYP ||
1273 // ISSUE: Disallowing abstract&private is no longer appropriate
1274 // in the presence of inner classes. Should it be deleted here?
1275 checkDisjoint(pos, flags,
1276 ABSTRACT,
1277 PRIVATE | STATIC | DEFAULT))
1278 &&
1279 checkDisjoint(pos, flags,
1280 STATIC | PRIVATE,
1281 DEFAULT)
1282 &&
1283 checkDisjoint(pos, flags,
1284 ABSTRACT | INTERFACE,
1285 FINAL | NATIVE | SYNCHRONIZED)
1286 &&
1287 checkDisjoint(pos, flags,
1288 PUBLIC,
1289 PRIVATE | PROTECTED)
1290 &&
1291 checkDisjoint(pos, flags,
1292 PRIVATE,
1293 PUBLIC | PROTECTED)
1294 &&
1295 // we are using `implicit` here as instance fields of value classes are implicitly final
1296 checkDisjoint(pos, flags | implicit,
1297 FINAL,
1298 VOLATILE)
1299 &&
1300 (sym.kind == TYP ||
1301 checkDisjoint(pos, flags,
1302 ABSTRACT | NATIVE,
1303 STRICTFP))
1304 && checkDisjoint(pos, flags,
1305 FINAL,
1306 SEALED | NON_SEALED)
1307 && checkDisjoint(pos, flags,
1308 SEALED,
1309 FINAL | NON_SEALED)
1310 && checkDisjoint(pos, flags,
1311 SEALED,
1312 ANNOTATION)
1313 && checkDisjoint(pos, flags,
1314 VALUE_CLASS,
1315 ANNOTATION)
1316 && checkDisjoint(pos, flags,
1317 VALUE_CLASS,
1318 INTERFACE) ) {
1319 // skip
1320 }
1321 return flags & (mask | ~ExtendedStandardFlags) | implicit;
1322 }
1323
1324 /** Determine if this enum should be implicitly final.
1325 *
1326 * If the enum has no specialized enum constants, it is final.
1327 *
1328 * If the enum does have specialized enum constants, it is
1329 * <i>not</i> final.
1330 */
1331 private long implicitEnumFinalFlag(JCTree tree) {
1332 if (!tree.hasTag(CLASSDEF)) return 0;
1333 class SpecialTreeVisitor extends JCTree.Visitor {
1334 boolean specialized;
1335 SpecialTreeVisitor() {
1336 this.specialized = false;
1337 }
1338
1339 @Override
1340 public void visitTree(JCTree tree) { /* no-op */ }
1341
1342 @Override
1343 public void visitVarDef(JCVariableDecl tree) {
1344 if ((tree.mods.flags & ENUM) != 0) {
1345 if (tree.init instanceof JCNewClass newClass && newClass.def != null) {
1346 specialized = true;
1347 }
1348 }
1349 }
1350 }
1351
1352 SpecialTreeVisitor sts = new SpecialTreeVisitor();
1353 JCClassDecl cdef = (JCClassDecl) tree;
1354 for (JCTree defs: cdef.defs) {
1355 defs.accept(sts);
1356 if (sts.specialized) return allowSealed ? SEALED : 0;
1357 }
1358 return FINAL;
1359 }
1360
1361 /* *************************************************************************
1362 * Type Validation
1363 **************************************************************************/
1364
1365 /** Validate a type expression. That is,
1366 * check that all type arguments of a parametric type are within
1367 * their bounds. This must be done in a second phase after type attribution
1368 * since a class might have a subclass as type parameter bound. E.g:
1369 *
1370 * <pre>{@code
1371 * class B<A extends C> { ... }
1372 * class C extends B<C> { ... }
1373 * }</pre>
1374 *
1375 * and we can't make sure that the bound is already attributed because
1376 * of possible cycles.
1377 *
1378 * Visitor method: Validate a type expression, if it is not null, catching
1379 * and reporting any completion failures.
1380 */
1381 void validate(JCTree tree, Env<AttrContext> env) {
1382 validate(tree, env, true);
1383 }
1384 void validate(JCTree tree, Env<AttrContext> env, boolean checkRaw) {
1385 new Validator(env).validateTree(tree, checkRaw, true);
1386 }
1387
1388 /** Visitor method: Validate a list of type expressions.
1389 */
1390 void validate(List<? extends JCTree> trees, Env<AttrContext> env) {
1391 for (List<? extends JCTree> l = trees; l.nonEmpty(); l = l.tail)
1392 validate(l.head, env);
1393 }
1394
1395 /** A visitor class for type validation.
1396 */
1397 class Validator extends JCTree.Visitor {
1398
1399 boolean checkRaw;
1400 boolean isOuter;
1401 Env<AttrContext> env;
1402
1403 Validator(Env<AttrContext> env) {
1404 this.env = env;
1405 }
1406
1407 @Override
1408 public void visitTypeArray(JCArrayTypeTree tree) {
1409 validateTree(tree.elemtype, checkRaw, isOuter);
1410 }
1411
1412 @Override
1413 public void visitTypeApply(JCTypeApply tree) {
1414 if (tree.type.hasTag(CLASS)) {
1415 List<JCExpression> args = tree.arguments;
1416 List<Type> forms = tree.type.tsym.type.getTypeArguments();
1417
1418 Type incompatibleArg = firstIncompatibleTypeArg(tree.type);
1419 if (incompatibleArg != null) {
1420 for (JCTree arg : tree.arguments) {
1421 if (arg.type == incompatibleArg) {
1422 log.error(arg, Errors.NotWithinBounds(incompatibleArg, forms.head));
1423 }
1424 forms = forms.tail;
1425 }
1426 }
1427
1428 forms = tree.type.tsym.type.getTypeArguments();
1429
1430 boolean is_java_lang_Class = tree.type.tsym.flatName() == names.java_lang_Class;
1431
1432 // For matching pairs of actual argument types `a' and
1433 // formal type parameters with declared bound `b' ...
1434 while (args.nonEmpty() && forms.nonEmpty()) {
1435 validateTree(args.head,
1436 !(isOuter && is_java_lang_Class),
1437 false);
1438 args = args.tail;
1439 forms = forms.tail;
1440 }
1441
1442 // Check that this type is either fully parameterized, or
1443 // not parameterized at all.
1444 if (tree.type.getEnclosingType().isRaw())
1445 log.error(tree.pos(), Errors.ImproperlyFormedTypeInnerRawParam);
1446 if (tree.clazz.hasTag(SELECT))
1447 visitSelectInternal((JCFieldAccess)tree.clazz);
1448 }
1449 }
1450
1451 @Override
1452 public void visitTypeParameter(JCTypeParameter tree) {
1453 validateTrees(tree.bounds, true, isOuter);
1454 checkClassBounds(tree.pos(), tree.type);
1455 }
1456
1457 @Override
1458 public void visitWildcard(JCWildcard tree) {
1459 if (tree.inner != null)
1460 validateTree(tree.inner, true, isOuter);
1461 }
1462
1463 @Override
1464 public void visitSelect(JCFieldAccess tree) {
1465 if (tree.type.hasTag(CLASS)) {
1466 visitSelectInternal(tree);
1467
1468 // Check that this type is either fully parameterized, or
1469 // not parameterized at all.
1470 if (tree.selected.type.isParameterized() && tree.type.tsym.type.getTypeArguments().nonEmpty())
1471 log.error(tree.pos(), Errors.ImproperlyFormedTypeParamMissing);
1472 }
1473 }
1474
1475 public void visitSelectInternal(JCFieldAccess tree) {
1476 if (tree.type.tsym.isStatic() &&
1477 tree.selected.type.isParameterized()) {
1478 // The enclosing type is not a class, so we are
1479 // looking at a static member type. However, the
1480 // qualifying expression is parameterized.
1481 log.error(tree.pos(), Errors.CantSelectStaticClassFromParamType);
1482 } else {
1483 // otherwise validate the rest of the expression
1484 tree.selected.accept(this);
1485 }
1486 }
1487
1488 @Override
1489 public void visitAnnotatedType(JCAnnotatedType tree) {
1490 tree.underlyingType.accept(this);
1491 }
1492
1493 @Override
1494 public void visitTypeIdent(JCPrimitiveTypeTree that) {
1495 if (that.type.hasTag(TypeTag.VOID)) {
1496 log.error(that.pos(), Errors.VoidNotAllowedHere);
1497 }
1498 super.visitTypeIdent(that);
1499 }
1500
1501 /** Default visitor method: do nothing.
1502 */
1503 @Override
1504 public void visitTree(JCTree tree) {
1505 }
1506
1507 public void validateTree(JCTree tree, boolean checkRaw, boolean isOuter) {
1508 if (tree != null) {
1509 boolean prevCheckRaw = this.checkRaw;
1510 this.checkRaw = checkRaw;
1511 this.isOuter = isOuter;
1512
1513 try {
1514 tree.accept(this);
1515 if (checkRaw)
1516 checkRaw(tree, env);
1517 } catch (CompletionFailure ex) {
1518 completionError(tree.pos(), ex);
1519 } finally {
1520 this.checkRaw = prevCheckRaw;
1521 }
1522 }
1523 }
1524
1525 public void validateTrees(List<? extends JCTree> trees, boolean checkRaw, boolean isOuter) {
1526 for (List<? extends JCTree> l = trees; l.nonEmpty(); l = l.tail)
1527 validateTree(l.head, checkRaw, isOuter);
1528 }
1529 }
1530
1531 void checkRaw(JCTree tree, Env<AttrContext> env) {
1532 if (tree.type.hasTag(CLASS) &&
1533 !TreeInfo.isDiamond(tree) &&
1534 !withinAnonConstr(env) &&
1535 tree.type.isRaw()) {
1536 log.warning(tree.pos(), LintWarnings.RawClassUse(tree.type, tree.type.tsym.type));
1537 }
1538 }
1539 //where
1540 private boolean withinAnonConstr(Env<AttrContext> env) {
1541 return env.enclClass.name.isEmpty() &&
1542 env.enclMethod != null && env.enclMethod.name == names.init;
1543 }
1544
1545 /* *************************************************************************
1546 * Exception checking
1547 **************************************************************************/
1548
1549 /* The following methods treat classes as sets that contain
1550 * the class itself and all their subclasses
1551 */
1552
1553 /** Is given type a subtype of some of the types in given list?
1554 */
1555 boolean subset(Type t, List<Type> ts) {
1556 for (List<Type> l = ts; l.nonEmpty(); l = l.tail)
1557 if (types.isSubtype(t, l.head)) return true;
1558 return false;
1559 }
1560
1561 /** Is given type a subtype or supertype of
1562 * some of the types in given list?
1563 */
1564 boolean intersects(Type t, List<Type> ts) {
1565 for (List<Type> l = ts; l.nonEmpty(); l = l.tail)
1566 if (types.isSubtype(t, l.head) || types.isSubtype(l.head, t)) return true;
1567 return false;
1568 }
1569
1570 /** Add type set to given type list, unless it is a subclass of some class
1571 * in the list.
1572 */
1573 List<Type> incl(Type t, List<Type> ts) {
1574 return subset(t, ts) ? ts : excl(t, ts).prepend(t);
1575 }
1576
1577 /** Remove type set from type set list.
1578 */
1579 List<Type> excl(Type t, List<Type> ts) {
1580 if (ts.isEmpty()) {
1581 return ts;
1582 } else {
1583 List<Type> ts1 = excl(t, ts.tail);
1584 if (types.isSubtype(ts.head, t)) return ts1;
1585 else if (ts1 == ts.tail) return ts;
1586 else return ts1.prepend(ts.head);
1587 }
1588 }
1589
1590 /** Form the union of two type set lists.
1591 */
1592 List<Type> union(List<Type> ts1, List<Type> ts2) {
1593 List<Type> ts = ts1;
1594 for (List<Type> l = ts2; l.nonEmpty(); l = l.tail)
1595 ts = incl(l.head, ts);
1596 return ts;
1597 }
1598
1599 /** Form the difference of two type lists.
1600 */
1601 List<Type> diff(List<Type> ts1, List<Type> ts2) {
1602 List<Type> ts = ts1;
1603 for (List<Type> l = ts2; l.nonEmpty(); l = l.tail)
1604 ts = excl(l.head, ts);
1605 return ts;
1606 }
1607
1608 /** Form the intersection of two type lists.
1609 */
1610 public List<Type> intersect(List<Type> ts1, List<Type> ts2) {
1611 List<Type> ts = List.nil();
1612 for (List<Type> l = ts1; l.nonEmpty(); l = l.tail)
1613 if (subset(l.head, ts2)) ts = incl(l.head, ts);
1614 for (List<Type> l = ts2; l.nonEmpty(); l = l.tail)
1615 if (subset(l.head, ts1)) ts = incl(l.head, ts);
1616 return ts;
1617 }
1618
1619 /** Is exc an exception symbol that need not be declared?
1620 */
1621 boolean isUnchecked(ClassSymbol exc) {
1622 return
1623 exc.kind == ERR ||
1624 exc.isSubClass(syms.errorType.tsym, types) ||
1625 exc.isSubClass(syms.runtimeExceptionType.tsym, types);
1626 }
1627
1628 /** Is exc an exception type that need not be declared?
1629 */
1630 boolean isUnchecked(Type exc) {
1631 return
1632 (exc.hasTag(TYPEVAR)) ? isUnchecked(types.supertype(exc)) :
1633 (exc.hasTag(CLASS)) ? isUnchecked((ClassSymbol)exc.tsym) :
1634 exc.hasTag(BOT);
1635 }
1636
1637 boolean isChecked(Type exc) {
1638 return !isUnchecked(exc);
1639 }
1640
1641 /** Same, but handling completion failures.
1642 */
1643 boolean isUnchecked(DiagnosticPosition pos, Type exc) {
1644 try {
1645 return isUnchecked(exc);
1646 } catch (CompletionFailure ex) {
1647 completionError(pos, ex);
1648 return true;
1649 }
1650 }
1651
1652 /** Is exc handled by given exception list?
1653 */
1654 boolean isHandled(Type exc, List<Type> handled) {
1655 return isUnchecked(exc) || subset(exc, handled);
1656 }
1657
1658 /** Return all exceptions in thrown list that are not in handled list.
1659 * @param thrown The list of thrown exceptions.
1660 * @param handled The list of handled exceptions.
1661 */
1662 List<Type> unhandled(List<Type> thrown, List<Type> handled) {
1663 List<Type> unhandled = List.nil();
1664 for (List<Type> l = thrown; l.nonEmpty(); l = l.tail)
1665 if (!isHandled(l.head, handled)) unhandled = unhandled.prepend(l.head);
1666 return unhandled;
1667 }
1668
1669 /* *************************************************************************
1670 * Overriding/Implementation checking
1671 **************************************************************************/
1672
1673 /** The level of access protection given by a flag set,
1674 * where PRIVATE is highest and PUBLIC is lowest.
1675 */
1676 static int protection(long flags) {
1677 switch ((short)(flags & AccessFlags)) {
1678 case PRIVATE: return 3;
1679 case PROTECTED: return 1;
1680 default:
1681 case PUBLIC: return 0;
1682 case 0: return 2;
1683 }
1684 }
1685
1686 /** A customized "cannot override" error message.
1687 * @param m The overriding method.
1688 * @param other The overridden method.
1689 * @return An internationalized string.
1690 */
1691 Fragment cannotOverride(MethodSymbol m, MethodSymbol other) {
1692 Symbol mloc = m.location();
1693 Symbol oloc = other.location();
1694
1695 if ((other.owner.flags() & INTERFACE) == 0)
1696 return Fragments.CantOverride(m, mloc, other, oloc);
1697 else if ((m.owner.flags() & INTERFACE) == 0)
1698 return Fragments.CantImplement(m, mloc, other, oloc);
1699 else
1700 return Fragments.ClashesWith(m, mloc, other, oloc);
1701 }
1702
1703 /** A customized "override" warning message.
1704 * @param m The overriding method.
1705 * @param other The overridden method.
1706 * @return An internationalized string.
1707 */
1708 Fragment uncheckedOverrides(MethodSymbol m, MethodSymbol other) {
1709 Symbol mloc = m.location();
1710 Symbol oloc = other.location();
1711
1712 if ((other.owner.flags() & INTERFACE) == 0)
1713 return Fragments.UncheckedOverride(m, mloc, other, oloc);
1714 else if ((m.owner.flags() & INTERFACE) == 0)
1715 return Fragments.UncheckedImplement(m, mloc, other, oloc);
1716 else
1717 return Fragments.UncheckedClashWith(m, mloc, other, oloc);
1718 }
1719
1720 /** A customized "override" warning message.
1721 * @param m The overriding method.
1722 * @param other The overridden method.
1723 * @return An internationalized string.
1724 */
1725 Fragment varargsOverrides(MethodSymbol m, MethodSymbol other) {
1726 Symbol mloc = m.location();
1727 Symbol oloc = other.location();
1728
1729 if ((other.owner.flags() & INTERFACE) == 0)
1730 return Fragments.VarargsOverride(m, mloc, other, oloc);
1731 else if ((m.owner.flags() & INTERFACE) == 0)
1732 return Fragments.VarargsImplement(m, mloc, other, oloc);
1733 else
1734 return Fragments.VarargsClashWith(m, mloc, other, oloc);
1735 }
1736
1737 /** Check that this method conforms with overridden method 'other'.
1738 * where `origin' is the class where checking started.
1739 * Complications:
1740 * (1) Do not check overriding of synthetic methods
1741 * (reason: they might be final).
1742 * todo: check whether this is still necessary.
1743 * (2) Admit the case where an interface proxy throws fewer exceptions
1744 * than the method it implements. Augment the proxy methods with the
1745 * undeclared exceptions in this case.
1746 * (3) When generics are enabled, admit the case where an interface proxy
1747 * has a result type
1748 * extended by the result type of the method it implements.
1749 * Change the proxies result type to the smaller type in this case.
1750 *
1751 * @param tree The tree from which positions
1752 * are extracted for errors.
1753 * @param m The overriding method.
1754 * @param other The overridden method.
1755 * @param origin The class of which the overriding method
1756 * is a member.
1757 */
1758 void checkOverride(JCTree tree,
1759 MethodSymbol m,
1760 MethodSymbol other,
1761 ClassSymbol origin) {
1762 // Don't check overriding of synthetic methods or by bridge methods.
1763 if ((m.flags() & (SYNTHETIC|BRIDGE)) != 0 || (other.flags() & SYNTHETIC) != 0) {
1764 return;
1765 }
1766
1767 // Error if static method overrides instance method (JLS 8.4.8.2).
1768 if ((m.flags() & STATIC) != 0 &&
1769 (other.flags() & STATIC) == 0) {
1770 log.error(TreeInfo.diagnosticPositionFor(m, tree),
1771 Errors.OverrideStatic(cannotOverride(m, other)));
1772 m.flags_field |= BAD_OVERRIDE;
1773 return;
1774 }
1775
1776 // Error if instance method overrides static or final
1777 // method (JLS 8.4.8.1).
1778 if ((other.flags() & FINAL) != 0 ||
1779 (m.flags() & STATIC) == 0 &&
1780 (other.flags() & STATIC) != 0) {
1781 log.error(TreeInfo.diagnosticPositionFor(m, tree),
1782 Errors.OverrideMeth(cannotOverride(m, other),
1783 asFlagSet(other.flags() & (FINAL | STATIC))));
1784 m.flags_field |= BAD_OVERRIDE;
1785 return;
1786 }
1787
1788 if ((m.owner.flags() & ANNOTATION) != 0) {
1789 // handled in validateAnnotationMethod
1790 return;
1791 }
1792
1793 // Error if overriding method has weaker access (JLS 8.4.8.3).
1794 if (protection(m.flags()) > protection(other.flags())) {
1795 log.error(TreeInfo.diagnosticPositionFor(m, tree),
1796 (other.flags() & AccessFlags) == 0 ?
1797 Errors.OverrideWeakerAccess(cannotOverride(m, other),
1798 "package") :
1799 Errors.OverrideWeakerAccess(cannotOverride(m, other),
1800 asFlagSet(other.flags() & AccessFlags)));
1801 m.flags_field |= BAD_OVERRIDE;
1802 return;
1803 }
1804
1805 if (shouldCheckPreview(m, other, origin)) {
1806 checkPreview(TreeInfo.diagnosticPositionFor(m, tree),
1807 m, origin.type, other);
1808 }
1809
1810 Type mt = types.memberType(origin.type, m);
1811 Type ot = types.memberType(origin.type, other);
1812 // Error if overriding result type is different
1813 // (or, in the case of generics mode, not a subtype) of
1814 // overridden result type. We have to rename any type parameters
1815 // before comparing types.
1816 List<Type> mtvars = mt.getTypeArguments();
1817 List<Type> otvars = ot.getTypeArguments();
1818 Type mtres = mt.getReturnType();
1819 Type otres = types.subst(ot.getReturnType(), otvars, mtvars);
1820
1821 overrideWarner.clear();
1822 boolean resultTypesOK =
1823 types.returnTypeSubstitutable(mt, ot, otres, overrideWarner);
1824 if (!resultTypesOK) {
1825 if ((m.flags() & STATIC) != 0 && (other.flags() & STATIC) != 0) {
1826 log.error(TreeInfo.diagnosticPositionFor(m, tree),
1827 Errors.OverrideIncompatibleRet(Fragments.CantHide(m, m.location(), other,
1828 other.location()), mtres, otres));
1829 m.flags_field |= BAD_OVERRIDE;
1830 } else {
1831 log.error(TreeInfo.diagnosticPositionFor(m, tree),
1832 Errors.OverrideIncompatibleRet(cannotOverride(m, other), mtres, otres));
1833 m.flags_field |= BAD_OVERRIDE;
1834 }
1835 return;
1836 } else if (overrideWarner.hasNonSilentLint(LintCategory.UNCHECKED)) {
1837 warnUnchecked(TreeInfo.diagnosticPositionFor(m, tree),
1838 LintWarnings.OverrideUncheckedRet(uncheckedOverrides(m, other), mtres, otres));
1839 }
1840
1841 // Error if overriding method throws an exception not reported
1842 // by overridden method.
1843 List<Type> otthrown = types.subst(ot.getThrownTypes(), otvars, mtvars);
1844 List<Type> unhandledErased = unhandled(mt.getThrownTypes(), types.erasure(otthrown));
1845 List<Type> unhandledUnerased = unhandled(mt.getThrownTypes(), otthrown);
1846 if (unhandledErased.nonEmpty()) {
1847 log.error(TreeInfo.diagnosticPositionFor(m, tree),
1848 Errors.OverrideMethDoesntThrow(cannotOverride(m, other), unhandledUnerased.head));
1849 m.flags_field |= BAD_OVERRIDE;
1850 return;
1851 }
1852 else if (unhandledUnerased.nonEmpty()) {
1853 warnUnchecked(TreeInfo.diagnosticPositionFor(m, tree),
1854 LintWarnings.OverrideUncheckedThrown(cannotOverride(m, other), unhandledUnerased.head));
1855 return;
1856 }
1857
1858 // Optional warning if varargs don't agree
1859 if ((((m.flags() ^ other.flags()) & Flags.VARARGS) != 0)) {
1860 log.warning(TreeInfo.diagnosticPositionFor(m, tree),
1861 ((m.flags() & Flags.VARARGS) != 0)
1862 ? LintWarnings.OverrideVarargsMissing(varargsOverrides(m, other))
1863 : LintWarnings.OverrideVarargsExtra(varargsOverrides(m, other)));
1864 }
1865
1866 // Warn if instance method overrides bridge method (compiler spec ??)
1867 if ((other.flags() & BRIDGE) != 0) {
1868 log.warning(TreeInfo.diagnosticPositionFor(m, tree),
1869 Warnings.OverrideBridge(uncheckedOverrides(m, other)));
1870 }
1871
1872 // Warn if a deprecated method overridden by a non-deprecated one.
1873 if (!isDeprecatedOverrideIgnorable(other, origin)) {
1874 checkDeprecated(() -> TreeInfo.diagnosticPositionFor(m, tree), m, other);
1875 }
1876 }
1877 // where
1878 private boolean shouldCheckPreview(MethodSymbol m, MethodSymbol other, ClassSymbol origin) {
1879 if (m.owner != origin ||
1880 //performance - only do the expensive checks when the overridden method is a Preview API:
1881 ((other.flags() & PREVIEW_API) == 0 &&
1882 (other.owner.flags() & PREVIEW_API) == 0)) {
1883 return false;
1884 }
1885
1886 for (Symbol s : types.membersClosure(origin.type, false).getSymbolsByName(m.name)) {
1887 if (m != s && m.overrides(s, origin, types, false)) {
1888 //only produce preview warnings or errors if "m" immediatelly overrides "other"
1889 //without intermediate overriding methods:
1890 return s == other;
1891 }
1892 }
1893
1894 return false;
1895 }
1896 private boolean isDeprecatedOverrideIgnorable(MethodSymbol m, ClassSymbol origin) {
1897 // If the method, m, is defined in an interface, then ignore the issue if the method
1898 // is only inherited via a supertype and also implemented in the supertype,
1899 // because in that case, we will rediscover the issue when examining the method
1900 // in the supertype.
1901 // If the method, m, is not defined in an interface, then the only time we need to
1902 // address the issue is when the method is the supertype implementation: any other
1903 // case, we will have dealt with when examining the supertype classes
1904 ClassSymbol mc = m.enclClass();
1905 Type st = types.supertype(origin.type);
1906 if (!st.hasTag(CLASS))
1907 return true;
1908 MethodSymbol stimpl = m.implementation((ClassSymbol)st.tsym, types, false);
1909
1910 if (mc != null && ((mc.flags() & INTERFACE) != 0)) {
1911 List<Type> intfs = types.interfaces(origin.type);
1912 return (intfs.contains(mc.type) ? false : (stimpl != null));
1913 }
1914 else
1915 return (stimpl != m);
1916 }
1917
1918
1919 // used to check if there were any unchecked conversions
1920 Warner overrideWarner = new Warner();
1921
1922 /** Check that a class does not inherit two concrete methods
1923 * with the same signature.
1924 * @param pos Position to be used for error reporting.
1925 * @param site The class type to be checked.
1926 */
1927 public void checkCompatibleConcretes(DiagnosticPosition pos, Type site) {
1928 Type sup = types.supertype(site);
1929 if (!sup.hasTag(CLASS)) return;
1930
1931 for (Type t1 = sup;
1932 t1.hasTag(CLASS) && t1.tsym.type.isParameterized();
1933 t1 = types.supertype(t1)) {
1934 for (Symbol s1 : t1.tsym.members().getSymbols(NON_RECURSIVE)) {
1935 if (s1.kind != MTH ||
1936 (s1.flags() & (STATIC|SYNTHETIC|BRIDGE)) != 0 ||
1937 !s1.isInheritedIn(site.tsym, types) ||
1938 ((MethodSymbol)s1).implementation(site.tsym,
1939 types,
1940 true) != s1)
1941 continue;
1942 Type st1 = types.memberType(t1, s1);
1943 int s1ArgsLength = st1.getParameterTypes().length();
1944 if (st1 == s1.type) continue;
1945
1946 for (Type t2 = sup;
1947 t2.hasTag(CLASS);
1948 t2 = types.supertype(t2)) {
1949 for (Symbol s2 : t2.tsym.members().getSymbolsByName(s1.name)) {
1950 if (s2 == s1 ||
1951 s2.kind != MTH ||
1952 (s2.flags() & (STATIC|SYNTHETIC|BRIDGE)) != 0 ||
1953 s2.type.getParameterTypes().length() != s1ArgsLength ||
1954 !s2.isInheritedIn(site.tsym, types) ||
1955 ((MethodSymbol)s2).implementation(site.tsym,
1956 types,
1957 true) != s2)
1958 continue;
1959 Type st2 = types.memberType(t2, s2);
1960 if (types.overrideEquivalent(st1, st2))
1961 log.error(pos,
1962 Errors.ConcreteInheritanceConflict(s1, t1, s2, t2, sup));
1963 }
1964 }
1965 }
1966 }
1967 }
1968
1969 /** Check that classes (or interfaces) do not each define an abstract
1970 * method with same name and arguments but incompatible return types.
1971 * @param pos Position to be used for error reporting.
1972 * @param t1 The first argument type.
1973 * @param t2 The second argument type.
1974 */
1975 public boolean checkCompatibleAbstracts(DiagnosticPosition pos,
1976 Type t1,
1977 Type t2,
1978 Type site) {
1979 if ((site.tsym.flags() & COMPOUND) != 0) {
1980 // special case for intersections: need to eliminate wildcards in supertypes
1981 t1 = types.capture(t1);
1982 t2 = types.capture(t2);
1983 }
1984 return firstIncompatibility(pos, t1, t2, site) == null;
1985 }
1986
1987 /** Return the first method which is defined with same args
1988 * but different return types in two given interfaces, or null if none
1989 * exists.
1990 * @param t1 The first type.
1991 * @param t2 The second type.
1992 * @param site The most derived type.
1993 * @return symbol from t2 that conflicts with one in t1.
1994 */
1995 private Symbol firstIncompatibility(DiagnosticPosition pos, Type t1, Type t2, Type site) {
1996 Map<TypeSymbol,Type> interfaces1 = new HashMap<>();
1997 closure(t1, interfaces1);
1998 Map<TypeSymbol,Type> interfaces2;
1999 if (t1 == t2)
2000 interfaces2 = interfaces1;
2001 else
2002 closure(t2, interfaces1, interfaces2 = new HashMap<>());
2003
2004 for (Type t3 : interfaces1.values()) {
2005 for (Type t4 : interfaces2.values()) {
2006 Symbol s = firstDirectIncompatibility(pos, t3, t4, site);
2007 if (s != null) return s;
2008 }
2009 }
2010 return null;
2011 }
2012
2013 /** Compute all the supertypes of t, indexed by type symbol. */
2014 private void closure(Type t, Map<TypeSymbol,Type> typeMap) {
2015 if (!t.hasTag(CLASS)) return;
2016 if (typeMap.put(t.tsym, t) == null) {
2017 closure(types.supertype(t), typeMap);
2018 for (Type i : types.interfaces(t))
2019 closure(i, typeMap);
2020 }
2021 }
2022
2023 /** Compute all the supertypes of t, indexed by type symbol (except those in typesSkip). */
2024 private void closure(Type t, Map<TypeSymbol,Type> typesSkip, Map<TypeSymbol,Type> typeMap) {
2025 if (!t.hasTag(CLASS)) return;
2026 if (typesSkip.get(t.tsym) != null) return;
2027 if (typeMap.put(t.tsym, t) == null) {
2028 closure(types.supertype(t), typesSkip, typeMap);
2029 for (Type i : types.interfaces(t))
2030 closure(i, typesSkip, typeMap);
2031 }
2032 }
2033
2034 /** Return the first method in t2 that conflicts with a method from t1. */
2035 private Symbol firstDirectIncompatibility(DiagnosticPosition pos, Type t1, Type t2, Type site) {
2036 for (Symbol s1 : t1.tsym.members().getSymbols(NON_RECURSIVE)) {
2037 Type st1 = null;
2038 if (s1.kind != MTH || !s1.isInheritedIn(site.tsym, types) ||
2039 (s1.flags() & SYNTHETIC) != 0) continue;
2040 Symbol impl = ((MethodSymbol)s1).implementation(site.tsym, types, false);
2041 if (impl != null && (impl.flags() & ABSTRACT) == 0) continue;
2042 for (Symbol s2 : t2.tsym.members().getSymbolsByName(s1.name)) {
2043 if (s1 == s2) continue;
2044 if (s2.kind != MTH || !s2.isInheritedIn(site.tsym, types) ||
2045 (s2.flags() & SYNTHETIC) != 0) continue;
2046 if (st1 == null) st1 = types.memberType(t1, s1);
2047 Type st2 = types.memberType(t2, s2);
2048 if (types.overrideEquivalent(st1, st2)) {
2049 List<Type> tvars1 = st1.getTypeArguments();
2050 List<Type> tvars2 = st2.getTypeArguments();
2051 Type rt1 = st1.getReturnType();
2052 Type rt2 = types.subst(st2.getReturnType(), tvars2, tvars1);
2053 boolean compat =
2054 types.isSameType(rt1, rt2) ||
2055 !rt1.isPrimitiveOrVoid() &&
2056 !rt2.isPrimitiveOrVoid() &&
2057 (types.covariantReturnType(rt1, rt2, types.noWarnings) ||
2058 types.covariantReturnType(rt2, rt1, types.noWarnings)) ||
2059 checkCommonOverriderIn(s1,s2,site);
2060 if (!compat) {
2061 if (types.isSameType(t1, t2)) {
2062 log.error(pos, Errors.IncompatibleDiffRetSameType(t1,
2063 s2.name, types.memberType(t2, s2).getParameterTypes()));
2064 } else {
2065 log.error(pos, Errors.TypesIncompatible(t1, t2,
2066 Fragments.IncompatibleDiffRet(s2.name, types.memberType(t2, s2).getParameterTypes())));
2067 }
2068 return s2;
2069 }
2070 } else if (checkNameClash((ClassSymbol)site.tsym, s1, s2) &&
2071 !checkCommonOverriderIn(s1, s2, site)) {
2072 log.error(pos, Errors.NameClashSameErasureNoOverride(
2073 s1.name, types.memberType(site, s1).asMethodType().getParameterTypes(), s1.location(),
2074 s2.name, types.memberType(site, s2).asMethodType().getParameterTypes(), s2.location()));
2075 return s2;
2076 }
2077 }
2078 }
2079 return null;
2080 }
2081 //WHERE
2082 boolean checkCommonOverriderIn(Symbol s1, Symbol s2, Type site) {
2083 Map<TypeSymbol,Type> supertypes = new HashMap<>();
2084 Type st1 = types.memberType(site, s1);
2085 Type st2 = types.memberType(site, s2);
2086 closure(site, supertypes);
2087 for (Type t : supertypes.values()) {
2088 for (Symbol s3 : t.tsym.members().getSymbolsByName(s1.name)) {
2089 if (s3 == s1 || s3 == s2 || s3.kind != MTH || (s3.flags() & (BRIDGE|SYNTHETIC)) != 0) continue;
2090 Type st3 = types.memberType(site,s3);
2091 if (types.overrideEquivalent(st3, st1) &&
2092 types.overrideEquivalent(st3, st2) &&
2093 types.returnTypeSubstitutable(st3, st1) &&
2094 types.returnTypeSubstitutable(st3, st2)) {
2095 return true;
2096 }
2097 }
2098 }
2099 return false;
2100 }
2101
2102 /** Check that a given method conforms with any method it overrides.
2103 * @param tree The tree from which positions are extracted
2104 * for errors.
2105 * @param m The overriding method.
2106 */
2107 void checkOverride(Env<AttrContext> env, JCMethodDecl tree, MethodSymbol m) {
2108 ClassSymbol origin = (ClassSymbol)m.owner;
2109 if ((origin.flags() & ENUM) != 0 && names.finalize.equals(m.name)) {
2110 if (m.overrides(syms.enumFinalFinalize, origin, types, false)) {
2111 log.error(tree.pos(), Errors.EnumNoFinalize);
2112 return;
2113 }
2114 }
2115 if (allowValueClasses && origin.isValueClass() && names.finalize.equals(m.name)) {
2116 if (m.overrides(syms.objectFinalize, origin, types, false)) {
2117 log.warning(tree.pos(), Warnings.ValueFinalize);
2118 }
2119 }
2120 if (allowRecords && origin.isRecord()) {
2121 // let's find out if this is a user defined accessor in which case the @Override annotation is acceptable
2122 Optional<? extends RecordComponent> recordComponent = origin.getRecordComponents().stream()
2123 .filter(rc -> rc.accessor == tree.sym && (rc.accessor.flags_field & GENERATED_MEMBER) == 0).findFirst();
2124 if (recordComponent.isPresent()) {
2125 return;
2126 }
2127 }
2128
2129 for (Type t = origin.type; t.hasTag(CLASS);
2130 t = types.supertype(t)) {
2131 if (t != origin.type) {
2132 checkOverride(tree, t, origin, m);
2133 }
2134 for (Type t2 : types.interfaces(t)) {
2135 checkOverride(tree, t2, origin, m);
2136 }
2137 }
2138
2139 final boolean explicitOverride = m.attribute(syms.overrideType.tsym) != null;
2140 // Check if this method must override a super method due to being annotated with @Override
2141 // or by virtue of being a member of a diamond inferred anonymous class. Latter case is to
2142 // be treated "as if as they were annotated" with @Override.
2143 boolean mustOverride = explicitOverride ||
2144 (env.info.isAnonymousDiamond && !m.isConstructor() && !m.isPrivate());
2145 if (mustOverride && !isOverrider(m)) {
2146 DiagnosticPosition pos = tree.pos();
2147 for (JCAnnotation a : tree.getModifiers().annotations) {
2148 if (a.annotationType.type.tsym == syms.overrideType.tsym) {
2149 pos = a.pos();
2150 break;
2151 }
2152 }
2153 log.error(pos,
2154 explicitOverride ? (m.isStatic() ? Errors.StaticMethodsCannotBeAnnotatedWithOverride(m, m.enclClass()) : Errors.MethodDoesNotOverrideSuperclass(m, m.enclClass())) :
2155 Errors.AnonymousDiamondMethodDoesNotOverrideSuperclass(Fragments.DiamondAnonymousMethodsImplicitlyOverride));
2156 }
2157 }
2158
2159 void checkOverride(JCTree tree, Type site, ClassSymbol origin, MethodSymbol m) {
2160 TypeSymbol c = site.tsym;
2161 for (Symbol sym : c.members().getSymbolsByName(m.name)) {
2162 if (m.overrides(sym, origin, types, false)) {
2163 if ((sym.flags() & ABSTRACT) == 0) {
2164 checkOverride(tree, m, (MethodSymbol)sym, origin);
2165 }
2166 }
2167 }
2168 }
2169
2170 private Predicate<Symbol> equalsHasCodeFilter = s -> MethodSymbol.implementation_filter.test(s) &&
2171 (s.flags() & BAD_OVERRIDE) == 0;
2172
2173 public void checkClassOverrideEqualsAndHashIfNeeded(DiagnosticPosition pos,
2174 ClassSymbol someClass) {
2175 /* At present, annotations cannot possibly have a method that is override
2176 * equivalent with Object.equals(Object) but in any case the condition is
2177 * fine for completeness.
2178 */
2179 if (someClass == (ClassSymbol)syms.objectType.tsym ||
2180 someClass.isInterface() || someClass.isEnum() ||
2181 (someClass.flags() & ANNOTATION) != 0 ||
2182 (someClass.flags() & ABSTRACT) != 0) return;
2183 //anonymous inner classes implementing interfaces need especial treatment
2184 if (someClass.isAnonymous()) {
2185 List<Type> interfaces = types.interfaces(someClass.type);
2186 if (interfaces != null && !interfaces.isEmpty() &&
2187 interfaces.head.tsym == syms.comparatorType.tsym) return;
2188 }
2189 checkClassOverrideEqualsAndHash(pos, someClass);
2190 }
2191
2192 private void checkClassOverrideEqualsAndHash(DiagnosticPosition pos,
2193 ClassSymbol someClass) {
2194 if (lint.isEnabled(LintCategory.OVERRIDES)) {
2195 MethodSymbol equalsAtObject = (MethodSymbol)syms.objectType
2196 .tsym.members().findFirst(names.equals);
2197 MethodSymbol hashCodeAtObject = (MethodSymbol)syms.objectType
2198 .tsym.members().findFirst(names.hashCode);
2199 MethodSymbol equalsImpl = types.implementation(equalsAtObject,
2200 someClass, false, equalsHasCodeFilter);
2201 boolean overridesEquals = equalsImpl != null &&
2202 equalsImpl.owner == someClass;
2203 boolean overridesHashCode = types.implementation(hashCodeAtObject,
2204 someClass, false, equalsHasCodeFilter) != hashCodeAtObject;
2205
2206 if (overridesEquals && !overridesHashCode) {
2207 log.warning(pos,
2208 LintWarnings.OverrideEqualsButNotHashcode(someClass));
2209 }
2210 }
2211 }
2212
2213 public void checkHasMain(DiagnosticPosition pos, ClassSymbol c) {
2214 boolean found = false;
2215
2216 for (Symbol sym : c.members().getSymbolsByName(names.main)) {
2217 if (sym.kind == MTH && (sym.flags() & PRIVATE) == 0) {
2218 MethodSymbol meth = (MethodSymbol)sym;
2219 if (!types.isSameType(meth.getReturnType(), syms.voidType)) {
2220 continue;
2221 }
2222 if (meth.params.isEmpty()) {
2223 found = true;
2224 break;
2225 }
2226 if (meth.params.size() != 1) {
2227 continue;
2228 }
2229 if (!types.isSameType(meth.params.head.type, types.makeArrayType(syms.stringType))) {
2230 continue;
2231 }
2232
2233 found = true;
2234 break;
2235 }
2236 }
2237
2238 if (!found) {
2239 log.error(pos, Errors.ImplicitClassDoesNotHaveMainMethod);
2240 }
2241 }
2242
2243 public void checkModuleName (JCModuleDecl tree) {
2244 Name moduleName = tree.sym.name;
2245 Assert.checkNonNull(moduleName);
2246 if (lint.isEnabled(LintCategory.MODULE)) {
2247 JCExpression qualId = tree.qualId;
2248 while (qualId != null) {
2249 Name componentName;
2250 DiagnosticPosition pos;
2251 switch (qualId.getTag()) {
2252 case SELECT:
2253 JCFieldAccess selectNode = ((JCFieldAccess) qualId);
2254 componentName = selectNode.name;
2255 pos = selectNode.pos();
2256 qualId = selectNode.selected;
2257 break;
2258 case IDENT:
2259 componentName = ((JCIdent) qualId).name;
2260 pos = qualId.pos();
2261 qualId = null;
2262 break;
2263 default:
2264 throw new AssertionError("Unexpected qualified identifier: " + qualId.toString());
2265 }
2266 if (componentName != null) {
2267 String moduleNameComponentString = componentName.toString();
2268 int nameLength = moduleNameComponentString.length();
2269 if (nameLength > 0 && Character.isDigit(moduleNameComponentString.charAt(nameLength - 1))) {
2270 log.warning(pos, LintWarnings.PoorChoiceForModuleName(componentName));
2271 }
2272 }
2273 }
2274 }
2275 }
2276
2277 private boolean checkNameClash(ClassSymbol origin, Symbol s1, Symbol s2) {
2278 ClashFilter cf = new ClashFilter(origin.type);
2279 return (cf.test(s1) &&
2280 cf.test(s2) &&
2281 types.hasSameArgs(s1.erasure(types), s2.erasure(types)));
2282 }
2283
2284
2285 /** Check that all abstract members of given class have definitions.
2286 * @param pos Position to be used for error reporting.
2287 * @param c The class.
2288 */
2289 void checkAllDefined(DiagnosticPosition pos, ClassSymbol c) {
2290 MethodSymbol undef = types.firstUnimplementedAbstract(c);
2291 if (undef != null) {
2292 MethodSymbol undef1 =
2293 new MethodSymbol(undef.flags(), undef.name,
2294 types.memberType(c.type, undef), undef.owner);
2295 log.error(pos,
2296 Errors.DoesNotOverrideAbstract(c, undef1, undef1.location()));
2297 }
2298 }
2299
2300 void checkNonCyclicDecl(JCClassDecl tree) {
2301 CycleChecker cc = new CycleChecker();
2302 cc.scan(tree);
2303 if (!cc.errorFound && !cc.partialCheck) {
2304 tree.sym.flags_field |= ACYCLIC;
2305 }
2306 }
2307
2308 class CycleChecker extends TreeScanner {
2309
2310 Set<Symbol> seenClasses = new HashSet<>();
2311 boolean errorFound = false;
2312 boolean partialCheck = false;
2313
2314 private void checkSymbol(DiagnosticPosition pos, Symbol sym) {
2315 if (sym != null && sym.kind == TYP) {
2316 Env<AttrContext> classEnv = enter.getEnv((TypeSymbol)sym);
2317 if (classEnv != null) {
2318 DiagnosticSource prevSource = log.currentSource();
2319 try {
2320 log.useSource(classEnv.toplevel.sourcefile);
2321 scan(classEnv.tree);
2322 }
2323 finally {
2324 log.useSource(prevSource.getFile());
2325 }
2326 } else if (sym.kind == TYP) {
2327 checkClass(pos, sym, List.nil());
2328 }
2329 } else if (sym == null || sym.kind != PCK) {
2330 //not completed yet
2331 partialCheck = true;
2332 }
2333 }
2334
2335 @Override
2336 public void visitSelect(JCFieldAccess tree) {
2337 super.visitSelect(tree);
2338 checkSymbol(tree.pos(), tree.sym);
2339 }
2340
2341 @Override
2342 public void visitIdent(JCIdent tree) {
2343 checkSymbol(tree.pos(), tree.sym);
2344 }
2345
2346 @Override
2347 public void visitTypeApply(JCTypeApply tree) {
2348 scan(tree.clazz);
2349 }
2350
2351 @Override
2352 public void visitTypeArray(JCArrayTypeTree tree) {
2353 scan(tree.elemtype);
2354 }
2355
2356 @Override
2357 public void visitClassDef(JCClassDecl tree) {
2358 List<JCTree> supertypes = List.nil();
2359 if (tree.getExtendsClause() != null) {
2360 supertypes = supertypes.prepend(tree.getExtendsClause());
2361 }
2362 if (tree.getImplementsClause() != null) {
2363 for (JCTree intf : tree.getImplementsClause()) {
2364 supertypes = supertypes.prepend(intf);
2365 }
2366 }
2367 checkClass(tree.pos(), tree.sym, supertypes);
2368 }
2369
2370 void checkClass(DiagnosticPosition pos, Symbol c, List<JCTree> supertypes) {
2371 if ((c.flags_field & ACYCLIC) != 0)
2372 return;
2373 if (seenClasses.contains(c)) {
2374 errorFound = true;
2375 log.error(pos, Errors.CyclicInheritance(c));
2376 seenClasses.stream()
2377 .filter(s -> !s.type.isErroneous())
2378 .filter(ClassSymbol.class::isInstance)
2379 .map(ClassSymbol.class::cast)
2380 .forEach(Check.this::handleCyclic);
2381 } else if (!c.type.isErroneous()) {
2382 try {
2383 seenClasses.add(c);
2384 if (c.type.hasTag(CLASS)) {
2385 if (supertypes.nonEmpty()) {
2386 scan(supertypes);
2387 }
2388 else {
2389 ClassType ct = (ClassType)c.type;
2390 if (ct.supertype_field == null ||
2391 ct.interfaces_field == null) {
2392 //not completed yet
2393 partialCheck = true;
2394 return;
2395 }
2396 checkSymbol(pos, ct.supertype_field.tsym);
2397 for (Type intf : ct.interfaces_field) {
2398 checkSymbol(pos, intf.tsym);
2399 }
2400 }
2401 if (c.owner.kind == TYP) {
2402 checkSymbol(pos, c.owner);
2403 }
2404 }
2405 } finally {
2406 seenClasses.remove(c);
2407 }
2408 }
2409 }
2410 }
2411
2412 /** Check for cyclic references. Issue an error if the
2413 * symbol of the type referred to has a LOCKED flag set.
2414 *
2415 * @param pos Position to be used for error reporting.
2416 * @param t The type referred to.
2417 */
2418 void checkNonCyclic(DiagnosticPosition pos, Type t) {
2419 checkNonCyclicInternal(pos, t);
2420 }
2421
2422
2423 void checkNonCyclic(DiagnosticPosition pos, TypeVar t) {
2424 checkNonCyclic1(pos, t, List.nil());
2425 }
2426
2427 private void checkNonCyclic1(DiagnosticPosition pos, Type t, List<TypeVar> seen) {
2428 final TypeVar tv;
2429 if (t.hasTag(TYPEVAR) && (t.tsym.flags() & UNATTRIBUTED) != 0)
2430 return;
2431 if (seen.contains(t)) {
2432 tv = (TypeVar)t;
2433 tv.setUpperBound(types.createErrorType(t));
2434 log.error(pos, Errors.CyclicInheritance(t));
2435 } else if (t.hasTag(TYPEVAR)) {
2436 tv = (TypeVar)t;
2437 seen = seen.prepend(tv);
2438 for (Type b : types.getBounds(tv))
2439 checkNonCyclic1(pos, b, seen);
2440 }
2441 }
2442
2443 /** Check for cyclic references. Issue an error if the
2444 * symbol of the type referred to has a LOCKED flag set.
2445 *
2446 * @param pos Position to be used for error reporting.
2447 * @param t The type referred to.
2448 * @return True if the check completed on all attributed classes
2449 */
2450 private boolean checkNonCyclicInternal(DiagnosticPosition pos, Type t) {
2451 boolean complete = true; // was the check complete?
2452 //- System.err.println("checkNonCyclicInternal("+t+");");//DEBUG
2453 Symbol c = t.tsym;
2454 if ((c.flags_field & ACYCLIC) != 0) return true;
2455
2456 if ((c.flags_field & LOCKED) != 0) {
2457 log.error(pos, Errors.CyclicInheritance(c));
2458 handleCyclic((ClassSymbol)c);
2459 } else if (!c.type.isErroneous()) {
2460 try {
2461 c.flags_field |= LOCKED;
2462 if (c.type.hasTag(CLASS)) {
2463 ClassType clazz = (ClassType)c.type;
2464 if (clazz.interfaces_field != null)
2465 for (List<Type> l=clazz.interfaces_field; l.nonEmpty(); l=l.tail)
2466 complete &= checkNonCyclicInternal(pos, l.head);
2467 if (clazz.supertype_field != null) {
2468 Type st = clazz.supertype_field;
2469 if (st != null && st.hasTag(CLASS))
2470 complete &= checkNonCyclicInternal(pos, st);
2471 }
2472 if (c.owner.kind == TYP)
2473 complete &= checkNonCyclicInternal(pos, c.owner.type);
2474 }
2475 } finally {
2476 c.flags_field &= ~LOCKED;
2477 }
2478 }
2479 if (complete)
2480 complete = ((c.flags_field & UNATTRIBUTED) == 0) && c.isCompleted();
2481 if (complete) c.flags_field |= ACYCLIC;
2482 return complete;
2483 }
2484
2485 /** Handle finding an inheritance cycle on a class by setting
2486 * the class' and its supertypes' types to the error type.
2487 **/
2488 private void handleCyclic(ClassSymbol c) {
2489 for (List<Type> l=types.interfaces(c.type); l.nonEmpty(); l=l.tail)
2490 l.head = types.createErrorType((ClassSymbol)l.head.tsym, Type.noType);
2491 Type st = types.supertype(c.type);
2492 if (st.hasTag(CLASS))
2493 ((ClassType)c.type).supertype_field = types.createErrorType((ClassSymbol)st.tsym, Type.noType);
2494 c.type = types.createErrorType(c, c.type);
2495 c.flags_field |= ACYCLIC;
2496 }
2497
2498 /** Check that all methods which implement some
2499 * method conform to the method they implement.
2500 * @param tree The class definition whose members are checked.
2501 */
2502 void checkImplementations(JCClassDecl tree) {
2503 checkImplementations(tree, tree.sym, tree.sym);
2504 }
2505 //where
2506 /** Check that all methods which implement some
2507 * method in `ic' conform to the method they implement.
2508 */
2509 void checkImplementations(JCTree tree, ClassSymbol origin, ClassSymbol ic) {
2510 for (List<Type> l = types.closure(ic.type); l.nonEmpty(); l = l.tail) {
2511 ClassSymbol lc = (ClassSymbol)l.head.tsym;
2512 if ((lc.flags() & ABSTRACT) != 0) {
2513 for (Symbol sym : lc.members().getSymbols(NON_RECURSIVE)) {
2514 if (sym.kind == MTH &&
2515 (sym.flags() & (STATIC|ABSTRACT)) == ABSTRACT) {
2516 MethodSymbol absmeth = (MethodSymbol)sym;
2517 MethodSymbol implmeth = absmeth.implementation(origin, types, false);
2518 if (implmeth != null && implmeth != absmeth &&
2519 (implmeth.owner.flags() & INTERFACE) ==
2520 (origin.flags() & INTERFACE)) {
2521 // don't check if implmeth is in a class, yet
2522 // origin is an interface. This case arises only
2523 // if implmeth is declared in Object. The reason is
2524 // that interfaces really don't inherit from
2525 // Object it's just that the compiler represents
2526 // things that way.
2527 checkOverride(tree, implmeth, absmeth, origin);
2528 }
2529 }
2530 }
2531 }
2532 }
2533 }
2534
2535 /** Check that all abstract methods implemented by a class are
2536 * mutually compatible.
2537 * @param pos Position to be used for error reporting.
2538 * @param c The class whose interfaces are checked.
2539 */
2540 void checkCompatibleSupertypes(DiagnosticPosition pos, Type c) {
2541 List<Type> supertypes = types.interfaces(c);
2542 Type supertype = types.supertype(c);
2543 if (supertype.hasTag(CLASS) &&
2544 (supertype.tsym.flags() & ABSTRACT) != 0)
2545 supertypes = supertypes.prepend(supertype);
2546 for (List<Type> l = supertypes; l.nonEmpty(); l = l.tail) {
2547 if (!l.head.getTypeArguments().isEmpty() &&
2548 !checkCompatibleAbstracts(pos, l.head, l.head, c))
2549 return;
2550 for (List<Type> m = supertypes; m != l; m = m.tail)
2551 if (!checkCompatibleAbstracts(pos, l.head, m.head, c))
2552 return;
2553 }
2554 checkCompatibleConcretes(pos, c);
2555
2556 Type identitySuper = null;
2557 Type superType = types.supertype(c);
2558 if (superType.isIdentityClass())
2559 identitySuper = superType;
2560 if (c.isValueClass() && identitySuper != null && identitySuper.tsym != syms.objectType.tsym) { // Object is special
2561 log.error(pos, Errors.ValueTypeHasIdentitySuperType(c, identitySuper));
2562 }
2563 }
2564
2565 /** Check that all non-override equivalent methods accessible from 'site'
2566 * are mutually compatible (JLS 8.4.8/9.4.1).
2567 *
2568 * @param pos Position to be used for error reporting.
2569 * @param site The class whose methods are checked.
2570 * @param sym The method symbol to be checked.
2571 */
2572 void checkOverrideClashes(DiagnosticPosition pos, Type site, MethodSymbol sym) {
2573 ClashFilter cf = new ClashFilter(site);
2574 //for each method m1 that is overridden (directly or indirectly)
2575 //by method 'sym' in 'site'...
2576
2577 ArrayList<Symbol> symbolsByName = new ArrayList<>();
2578 types.membersClosure(site, false).getSymbolsByName(sym.name, cf).forEach(symbolsByName::add);
2579 for (Symbol m1 : symbolsByName) {
2580 if (!sym.overrides(m1, site.tsym, types, false)) {
2581 continue;
2582 }
2583
2584 //...check each method m2 that is a member of 'site'
2585 for (Symbol m2 : symbolsByName) {
2586 if (m2 == m1) continue;
2587 //if (i) the signature of 'sym' is not a subsignature of m1 (seen as
2588 //a member of 'site') and (ii) m1 has the same erasure as m2, issue an error
2589 if (!types.isSubSignature(sym.type, types.memberType(site, m2)) &&
2590 types.hasSameArgs(m2.erasure(types), m1.erasure(types))) {
2591 sym.flags_field |= CLASH;
2592 if (m1 == sym) {
2593 log.error(pos, Errors.NameClashSameErasureNoOverride(
2594 m1.name, types.memberType(site, m1).asMethodType().getParameterTypes(), m1.location(),
2595 m2.name, types.memberType(site, m2).asMethodType().getParameterTypes(), m2.location()));
2596 } else {
2597 ClassType ct = (ClassType)site;
2598 String kind = ct.isInterface() ? "interface" : "class";
2599 log.error(pos, Errors.NameClashSameErasureNoOverride1(
2600 kind,
2601 ct.tsym.name,
2602 m1.name,
2603 types.memberType(site, m1).asMethodType().getParameterTypes(),
2604 m1.location(),
2605 m2.name,
2606 types.memberType(site, m2).asMethodType().getParameterTypes(),
2607 m2.location()));
2608 }
2609 return;
2610 }
2611 }
2612 }
2613 }
2614
2615 /** Check that all static methods accessible from 'site' are
2616 * mutually compatible (JLS 8.4.8).
2617 *
2618 * @param pos Position to be used for error reporting.
2619 * @param site The class whose methods are checked.
2620 * @param sym The method symbol to be checked.
2621 */
2622 void checkHideClashes(DiagnosticPosition pos, Type site, MethodSymbol sym) {
2623 ClashFilter cf = new ClashFilter(site);
2624 //for each method m1 that is a member of 'site'...
2625 for (Symbol s : types.membersClosure(site, true).getSymbolsByName(sym.name, cf)) {
2626 //if (i) the signature of 'sym' is not a subsignature of m1 (seen as
2627 //a member of 'site') and (ii) 'sym' has the same erasure as m1, issue an error
2628 if (!types.isSubSignature(sym.type, types.memberType(site, s))) {
2629 if (types.hasSameArgs(s.erasure(types), sym.erasure(types))) {
2630 log.error(pos,
2631 Errors.NameClashSameErasureNoHide(sym, sym.location(), s, s.location()));
2632 return;
2633 }
2634 }
2635 }
2636 }
2637
2638 //where
2639 private class ClashFilter implements Predicate<Symbol> {
2640
2641 Type site;
2642
2643 ClashFilter(Type site) {
2644 this.site = site;
2645 }
2646
2647 boolean shouldSkip(Symbol s) {
2648 return (s.flags() & CLASH) != 0 &&
2649 s.owner == site.tsym;
2650 }
2651
2652 @Override
2653 public boolean test(Symbol s) {
2654 return s.kind == MTH &&
2655 (s.flags() & SYNTHETIC) == 0 &&
2656 !shouldSkip(s) &&
2657 s.isInheritedIn(site.tsym, types) &&
2658 !s.isConstructor();
2659 }
2660 }
2661
2662 void checkDefaultMethodClashes(DiagnosticPosition pos, Type site) {
2663 DefaultMethodClashFilter dcf = new DefaultMethodClashFilter(site);
2664 for (Symbol m : types.membersClosure(site, false).getSymbols(dcf)) {
2665 Assert.check(m.kind == MTH);
2666 List<MethodSymbol> prov = types.interfaceCandidates(site, (MethodSymbol)m);
2667 if (prov.size() > 1) {
2668 ListBuffer<Symbol> abstracts = new ListBuffer<>();
2669 ListBuffer<Symbol> defaults = new ListBuffer<>();
2670 for (MethodSymbol provSym : prov) {
2671 if ((provSym.flags() & DEFAULT) != 0) {
2672 defaults = defaults.append(provSym);
2673 } else if ((provSym.flags() & ABSTRACT) != 0) {
2674 abstracts = abstracts.append(provSym);
2675 }
2676 if (defaults.nonEmpty() && defaults.size() + abstracts.size() >= 2) {
2677 //strong semantics - issue an error if two sibling interfaces
2678 //have two override-equivalent defaults - or if one is abstract
2679 //and the other is default
2680 Fragment diagKey;
2681 Symbol s1 = defaults.first();
2682 Symbol s2;
2683 if (defaults.size() > 1) {
2684 s2 = defaults.toList().tail.head;
2685 diagKey = Fragments.IncompatibleUnrelatedDefaults(Kinds.kindName(site.tsym), site,
2686 m.name, types.memberType(site, m).getParameterTypes(),
2687 s1.location(), s2.location());
2688
2689 } else {
2690 s2 = abstracts.first();
2691 diagKey = Fragments.IncompatibleAbstractDefault(Kinds.kindName(site.tsym), site,
2692 m.name, types.memberType(site, m).getParameterTypes(),
2693 s1.location(), s2.location());
2694 }
2695 log.error(pos, Errors.TypesIncompatible(s1.location().type, s2.location().type, diagKey));
2696 break;
2697 }
2698 }
2699 }
2700 }
2701 }
2702
2703 //where
2704 private class DefaultMethodClashFilter implements Predicate<Symbol> {
2705
2706 Type site;
2707
2708 DefaultMethodClashFilter(Type site) {
2709 this.site = site;
2710 }
2711
2712 @Override
2713 public boolean test(Symbol s) {
2714 return s.kind == MTH &&
2715 (s.flags() & DEFAULT) != 0 &&
2716 s.isInheritedIn(site.tsym, types) &&
2717 !s.isConstructor();
2718 }
2719 }
2720
2721 /** Report warnings for potentially ambiguous method declarations in the given site. */
2722 void checkPotentiallyAmbiguousOverloads(JCClassDecl tree, Type site) {
2723
2724 // Skip if warning not enabled
2725 if (!lint.isEnabled(LintCategory.OVERLOADS))
2726 return;
2727
2728 // Gather all of site's methods, including overridden methods, grouped by name (except Object methods)
2729 List<java.util.List<MethodSymbol>> methodGroups = methodsGroupedByName(site,
2730 new PotentiallyAmbiguousFilter(site), ArrayList::new);
2731
2732 // Build the predicate that determines if site is responsible for an ambiguity
2733 BiPredicate<MethodSymbol, MethodSymbol> responsible = buildResponsiblePredicate(site, methodGroups);
2734
2735 // Now remove overridden methods from each group, leaving only site's actual members
2736 methodGroups.forEach(list -> removePreempted(list, (m1, m2) -> m1.overrides(m2, site.tsym, types, false)));
2737
2738 // Allow site's own declared methods (only) to apply @SuppressWarnings("overloads")
2739 methodGroups.forEach(list -> list.removeIf(
2740 m -> m.owner == site.tsym && !lint.augment(m).isEnabled(LintCategory.OVERLOADS)));
2741
2742 // Warn about ambiguous overload method pairs for which site is responsible
2743 methodGroups.forEach(list -> compareAndRemove(list, (m1, m2) -> {
2744
2745 // See if this is an ambiguous overload for which "site" is responsible
2746 if (!potentiallyAmbiguousOverload(site, m1, m2) || !responsible.test(m1, m2))
2747 return 0;
2748
2749 // Locate the warning at one of the methods, if possible
2750 DiagnosticPosition pos =
2751 m1.owner == site.tsym ? TreeInfo.diagnosticPositionFor(m1, tree) :
2752 m2.owner == site.tsym ? TreeInfo.diagnosticPositionFor(m2, tree) :
2753 tree.pos();
2754
2755 // Log the warning
2756 log.warning(pos,
2757 LintWarnings.PotentiallyAmbiguousOverload(
2758 m1.asMemberOf(site, types), m1.location(),
2759 m2.asMemberOf(site, types), m2.location()));
2760
2761 // Don't warn again for either of these two methods
2762 return FIRST | SECOND;
2763 }));
2764 }
2765
2766 /** Build a predicate that determines, given two methods that are members of the given class,
2767 * whether the class should be held "responsible" if the methods are potentially ambiguous.
2768 *
2769 * Sometimes ambiguous methods are unavoidable because they're inherited from a supertype.
2770 * For example, any subtype of Spliterator.OfInt will have ambiguities for both
2771 * forEachRemaining() and tryAdvance() (in both cases the overloads are IntConsumer and
2772 * Consumer<? super Integer>). So we only want to "blame" a class when that class is
2773 * itself responsible for creating the ambiguity. We declare that a class C is "responsible"
2774 * for the ambiguity between two methods m1 and m2 if there is no direct supertype T of C
2775 * such that m1 and m2, or some overrides thereof, both exist in T and are ambiguous in T.
2776 * As an optimization, we first check if either method is declared in C and does not override
2777 * any other methods; in this case the class is definitely responsible.
2778 */
2779 BiPredicate<MethodSymbol, MethodSymbol> buildResponsiblePredicate(Type site,
2780 List<? extends Collection<MethodSymbol>> methodGroups) {
2781
2782 // Define the "overrides" predicate
2783 BiPredicate<MethodSymbol, MethodSymbol> overrides = (m1, m2) -> m1.overrides(m2, site.tsym, types, false);
2784
2785 // Map each method declared in site to a list of the supertype method(s) it directly overrides
2786 HashMap<MethodSymbol, ArrayList<MethodSymbol>> overriddenMethodsMap = new HashMap<>();
2787 methodGroups.forEach(list -> {
2788 for (MethodSymbol m : list) {
2789
2790 // Skip methods not declared in site
2791 if (m.owner != site.tsym)
2792 continue;
2793
2794 // Gather all supertype methods overridden by m, directly or indirectly
2795 ArrayList<MethodSymbol> overriddenMethods = list.stream()
2796 .filter(m2 -> m2 != m && overrides.test(m, m2))
2797 .collect(Collectors.toCollection(ArrayList::new));
2798
2799 // Eliminate non-direct overrides
2800 removePreempted(overriddenMethods, overrides);
2801
2802 // Add to map
2803 overriddenMethodsMap.put(m, overriddenMethods);
2804 }
2805 });
2806
2807 // Build the predicate
2808 return (m1, m2) -> {
2809
2810 // Get corresponding supertype methods (if declared in site)
2811 java.util.List<MethodSymbol> overriddenMethods1 = overriddenMethodsMap.get(m1);
2812 java.util.List<MethodSymbol> overriddenMethods2 = overriddenMethodsMap.get(m2);
2813
2814 // Quick check for the case where a method was added by site itself
2815 if (overriddenMethods1 != null && overriddenMethods1.isEmpty())
2816 return true;
2817 if (overriddenMethods2 != null && overriddenMethods2.isEmpty())
2818 return true;
2819
2820 // Get each method's corresponding method(s) from supertypes of site
2821 java.util.List<MethodSymbol> supertypeMethods1 = overriddenMethods1 != null ?
2822 overriddenMethods1 : Collections.singletonList(m1);
2823 java.util.List<MethodSymbol> supertypeMethods2 = overriddenMethods2 != null ?
2824 overriddenMethods2 : Collections.singletonList(m2);
2825
2826 // See if we can blame some direct supertype instead
2827 return types.directSupertypes(site).stream()
2828 .filter(stype -> stype != syms.objectType)
2829 .map(stype -> stype.tsym.type) // view supertype in its original form
2830 .noneMatch(stype -> {
2831 for (MethodSymbol sm1 : supertypeMethods1) {
2832 if (!types.isSubtype(types.erasure(stype), types.erasure(sm1.owner.type)))
2833 continue;
2834 for (MethodSymbol sm2 : supertypeMethods2) {
2835 if (!types.isSubtype(types.erasure(stype), types.erasure(sm2.owner.type)))
2836 continue;
2837 if (potentiallyAmbiguousOverload(stype, sm1, sm2))
2838 return true;
2839 }
2840 }
2841 return false;
2842 });
2843 };
2844 }
2845
2846 /** Gather all of site's methods, including overridden methods, grouped and sorted by name,
2847 * after applying the given filter.
2848 */
2849 <C extends Collection<MethodSymbol>> List<C> methodsGroupedByName(Type site,
2850 Predicate<Symbol> filter, Supplier<? extends C> groupMaker) {
2851 Iterable<Symbol> symbols = types.membersClosure(site, false).getSymbols(filter, RECURSIVE);
2852 return StreamSupport.stream(symbols.spliterator(), false)
2853 .map(MethodSymbol.class::cast)
2854 .collect(Collectors.groupingBy(m -> m.name, Collectors.toCollection(groupMaker)))
2855 .entrySet()
2856 .stream()
2857 .sorted(Comparator.comparing(e -> e.getKey().toString()))
2858 .map(Map.Entry::getValue)
2859 .collect(List.collector());
2860 }
2861
2862 /** Compare elements in a list pair-wise in order to remove some of them.
2863 * @param list mutable list of items
2864 * @param comparer returns flag bit(s) to remove FIRST and/or SECOND
2865 */
2866 <T> void compareAndRemove(java.util.List<T> list, ToIntBiFunction<? super T, ? super T> comparer) {
2867 for (int index1 = 0; index1 < list.size() - 1; index1++) {
2868 T item1 = list.get(index1);
2869 for (int index2 = index1 + 1; index2 < list.size(); index2++) {
2870 T item2 = list.get(index2);
2871 int flags = comparer.applyAsInt(item1, item2);
2872 if ((flags & SECOND) != 0)
2873 list.remove(index2--); // remove item2
2874 if ((flags & FIRST) != 0) {
2875 list.remove(index1--); // remove item1
2876 break;
2877 }
2878 }
2879 }
2880 }
2881
2882 /** Remove elements in a list that are preempted by some other element in the list.
2883 * @param list mutable list of items
2884 * @param preempts decides if one item preempts another, causing the second one to be removed
2885 */
2886 <T> void removePreempted(java.util.List<T> list, BiPredicate<? super T, ? super T> preempts) {
2887 compareAndRemove(list, (item1, item2) -> {
2888 int flags = 0;
2889 if (preempts.test(item1, item2))
2890 flags |= SECOND;
2891 if (preempts.test(item2, item1))
2892 flags |= FIRST;
2893 return flags;
2894 });
2895 }
2896
2897 /** Filters method candidates for the "potentially ambiguous method" check */
2898 class PotentiallyAmbiguousFilter extends ClashFilter {
2899
2900 PotentiallyAmbiguousFilter(Type site) {
2901 super(site);
2902 }
2903
2904 @Override
2905 boolean shouldSkip(Symbol s) {
2906 return s.owner.type.tsym == syms.objectType.tsym || super.shouldSkip(s);
2907 }
2908 }
2909
2910 /**
2911 * Report warnings for potentially ambiguous method declarations. Two declarations
2912 * are potentially ambiguous if they feature two unrelated functional interface
2913 * in same argument position (in which case, a call site passing an implicit
2914 * lambda would be ambiguous). This assumes they already have the same name.
2915 */
2916 boolean potentiallyAmbiguousOverload(Type site, MethodSymbol msym1, MethodSymbol msym2) {
2917 Assert.check(msym1.name == msym2.name);
2918 if (msym1 == msym2)
2919 return false;
2920 Type mt1 = types.memberType(site, msym1);
2921 Type mt2 = types.memberType(site, msym2);
2922 //if both generic methods, adjust type variables
2923 if (mt1.hasTag(FORALL) && mt2.hasTag(FORALL) &&
2924 types.hasSameBounds((ForAll)mt1, (ForAll)mt2)) {
2925 mt2 = types.subst(mt2, ((ForAll)mt2).tvars, ((ForAll)mt1).tvars);
2926 }
2927 //expand varargs methods if needed
2928 int maxLength = Math.max(mt1.getParameterTypes().length(), mt2.getParameterTypes().length());
2929 List<Type> args1 = rs.adjustArgs(mt1.getParameterTypes(), msym1, maxLength, true);
2930 List<Type> args2 = rs.adjustArgs(mt2.getParameterTypes(), msym2, maxLength, true);
2931 //if arities don't match, exit
2932 if (args1.length() != args2.length())
2933 return false;
2934 boolean potentiallyAmbiguous = false;
2935 while (args1.nonEmpty() && args2.nonEmpty()) {
2936 Type s = args1.head;
2937 Type t = args2.head;
2938 if (!types.isSubtype(t, s) && !types.isSubtype(s, t)) {
2939 if (types.isFunctionalInterface(s) && types.isFunctionalInterface(t) &&
2940 types.findDescriptorType(s).getParameterTypes().length() > 0 &&
2941 types.findDescriptorType(s).getParameterTypes().length() ==
2942 types.findDescriptorType(t).getParameterTypes().length()) {
2943 potentiallyAmbiguous = true;
2944 } else {
2945 return false;
2946 }
2947 }
2948 args1 = args1.tail;
2949 args2 = args2.tail;
2950 }
2951 return potentiallyAmbiguous;
2952 }
2953
2954 // Apply special flag "-XDwarnOnAccessToMembers" which turns on just this particular warning for all types of access
2955 void checkAccessFromSerializableElement(final JCTree tree, boolean isLambda) {
2956 if (warnOnAnyAccessToMembers || isLambda)
2957 checkAccessFromSerializableElementInner(tree, isLambda);
2958 }
2959
2960 private void checkAccessFromSerializableElementInner(final JCTree tree, boolean isLambda) {
2961 Symbol sym = TreeInfo.symbol(tree);
2962 if (!sym.kind.matches(KindSelector.VAL_MTH)) {
2963 return;
2964 }
2965
2966 if (sym.kind == VAR) {
2967 if ((sym.flags() & PARAMETER) != 0 ||
2968 sym.isDirectlyOrIndirectlyLocal() ||
2969 sym.name == names._this ||
2970 sym.name == names._super) {
2971 return;
2972 }
2973 }
2974
2975 if (!types.isSubtype(sym.owner.type, syms.serializableType) && isEffectivelyNonPublic(sym)) {
2976 DiagnosticFlag flag = warnOnAnyAccessToMembers ? DiagnosticFlag.DEFAULT_ENABLED : null;
2977 if (isLambda) {
2978 if (belongsToRestrictedPackage(sym)) {
2979 log.warning(flag, tree.pos(), LintWarnings.AccessToMemberFromSerializableLambda(sym));
2980 }
2981 } else {
2982 log.warning(flag, tree.pos(), LintWarnings.AccessToMemberFromSerializableElement(sym));
2983 }
2984 }
2985 }
2986
2987 private boolean isEffectivelyNonPublic(Symbol sym) {
2988 if (sym.packge() == syms.rootPackage) {
2989 return false;
2990 }
2991
2992 while (sym.kind != PCK) {
2993 if ((sym.flags() & PUBLIC) == 0) {
2994 return true;
2995 }
2996 sym = sym.owner;
2997 }
2998 return false;
2999 }
3000
3001 private boolean belongsToRestrictedPackage(Symbol sym) {
3002 String fullName = sym.packge().fullname.toString();
3003 return fullName.startsWith("java.") ||
3004 fullName.startsWith("javax.") ||
3005 fullName.startsWith("sun.") ||
3006 fullName.contains(".internal.");
3007 }
3008
3009 /** Check that class c does not implement directly or indirectly
3010 * the same parameterized interface with two different argument lists.
3011 * @param pos Position to be used for error reporting.
3012 * @param type The type whose interfaces are checked.
3013 */
3014 void checkClassBounds(DiagnosticPosition pos, Type type) {
3015 checkClassBounds(pos, new HashMap<TypeSymbol,Type>(), type);
3016 }
3017 //where
3018 /** Enter all interfaces of type `type' into the hash table `seensofar'
3019 * with their class symbol as key and their type as value. Make
3020 * sure no class is entered with two different types.
3021 */
3022 void checkClassBounds(DiagnosticPosition pos,
3023 Map<TypeSymbol,Type> seensofar,
3024 Type type) {
3025 if (type.isErroneous()) return;
3026 for (List<Type> l = types.interfaces(type); l.nonEmpty(); l = l.tail) {
3027 Type it = l.head;
3028 if (type.hasTag(CLASS) && !it.hasTag(CLASS)) continue; // JLS 8.1.5
3029
3030 Type oldit = seensofar.put(it.tsym, it);
3031 if (oldit != null) {
3032 List<Type> oldparams = oldit.allparams();
3033 List<Type> newparams = it.allparams();
3034 if (!types.containsTypeEquivalent(oldparams, newparams))
3035 log.error(pos,
3036 Errors.CantInheritDiffArg(it.tsym,
3037 Type.toString(oldparams),
3038 Type.toString(newparams)));
3039 }
3040 checkClassBounds(pos, seensofar, it);
3041 }
3042 Type st = types.supertype(type);
3043 if (type.hasTag(CLASS) && !st.hasTag(CLASS)) return; // JLS 8.1.4
3044 if (st != Type.noType) checkClassBounds(pos, seensofar, st);
3045 }
3046
3047 /** Enter interface into into set.
3048 * If it existed already, issue a "repeated interface" error.
3049 */
3050 void checkNotRepeated(DiagnosticPosition pos, Type it, Set<Symbol> its) {
3051 if (its.contains(it.tsym))
3052 log.error(pos, Errors.RepeatedInterface);
3053 else {
3054 its.add(it.tsym);
3055 }
3056 }
3057
3058 /* *************************************************************************
3059 * Check annotations
3060 **************************************************************************/
3061
3062 /**
3063 * Recursively validate annotations values
3064 */
3065 void validateAnnotationTree(JCTree tree) {
3066 class AnnotationValidator extends TreeScanner {
3067 @Override
3068 public void visitAnnotation(JCAnnotation tree) {
3069 if (!tree.type.isErroneous() && tree.type.tsym.isAnnotationType()) {
3070 super.visitAnnotation(tree);
3071 validateAnnotation(tree);
3072 }
3073 }
3074 }
3075 tree.accept(new AnnotationValidator());
3076 }
3077
3078 /**
3079 * {@literal
3080 * Annotation types are restricted to primitives, String, an
3081 * enum, an annotation, Class, Class<?>, Class<? extends
3082 * Anything>, arrays of the preceding.
3083 * }
3084 */
3085 void validateAnnotationType(JCTree restype) {
3086 // restype may be null if an error occurred, so don't bother validating it
3087 if (restype != null) {
3088 validateAnnotationType(restype.pos(), restype.type);
3089 }
3090 }
3091
3092 void validateAnnotationType(DiagnosticPosition pos, Type type) {
3093 if (type.isPrimitive()) return;
3094 if (types.isSameType(type, syms.stringType)) return;
3095 if ((type.tsym.flags() & Flags.ENUM) != 0) return;
3096 if ((type.tsym.flags() & Flags.ANNOTATION) != 0) return;
3097 if (types.cvarLowerBound(type).tsym == syms.classType.tsym) return;
3098 if (types.isArray(type) && !types.isArray(types.elemtype(type))) {
3099 validateAnnotationType(pos, types.elemtype(type));
3100 return;
3101 }
3102 log.error(pos, Errors.InvalidAnnotationMemberType);
3103 }
3104
3105 /**
3106 * "It is also a compile-time error if any method declared in an
3107 * annotation type has a signature that is override-equivalent to
3108 * that of any public or protected method declared in class Object
3109 * or in the interface annotation.Annotation."
3110 *
3111 * @jls 9.6 Annotation Types
3112 */
3113 void validateAnnotationMethod(DiagnosticPosition pos, MethodSymbol m) {
3114 for (Type sup = syms.annotationType; sup.hasTag(CLASS); sup = types.supertype(sup)) {
3115 Scope s = sup.tsym.members();
3116 for (Symbol sym : s.getSymbolsByName(m.name)) {
3117 if (sym.kind == MTH &&
3118 (sym.flags() & (PUBLIC | PROTECTED)) != 0 &&
3119 types.overrideEquivalent(m.type, sym.type))
3120 log.error(pos, Errors.IntfAnnotationMemberClash(sym, sup));
3121 }
3122 }
3123 }
3124
3125 /** Check the annotations of a symbol.
3126 */
3127 public void validateAnnotations(List<JCAnnotation> annotations, JCTree declarationTree, Symbol s) {
3128 for (JCAnnotation a : annotations)
3129 validateAnnotation(a, declarationTree, s);
3130 }
3131
3132 /** Check the type annotations.
3133 */
3134 public void validateTypeAnnotations(List<JCAnnotation> annotations, Symbol s, boolean isTypeParameter) {
3135 for (JCAnnotation a : annotations)
3136 validateTypeAnnotation(a, s, isTypeParameter);
3137 }
3138
3139 /** Check an annotation of a symbol.
3140 */
3141 private void validateAnnotation(JCAnnotation a, JCTree declarationTree, Symbol s) {
3142 /** NOTE: if annotation processors are present, annotation processing rounds can happen after this method,
3143 * this can impact in particular records for which annotations are forcibly propagated.
3144 */
3145 validateAnnotationTree(a);
3146 boolean isRecordMember = ((s.flags_field & RECORD) != 0 || s.enclClass() != null && s.enclClass().isRecord());
3147
3148 boolean isRecordField = (s.flags_field & RECORD) != 0 &&
3149 declarationTree.hasTag(VARDEF) &&
3150 s.owner.kind == TYP;
3151
3152 if (isRecordField) {
3153 // first we need to check if the annotation is applicable to records
3154 Name[] targets = getTargetNames(a);
3155 boolean appliesToRecords = false;
3156 for (Name target : targets) {
3157 appliesToRecords =
3158 target == names.FIELD ||
3159 target == names.PARAMETER ||
3160 target == names.METHOD ||
3161 target == names.TYPE_USE ||
3162 target == names.RECORD_COMPONENT;
3163 if (appliesToRecords) {
3164 break;
3165 }
3166 }
3167 if (!appliesToRecords) {
3168 log.error(a.pos(), Errors.AnnotationTypeNotApplicable);
3169 } else {
3170 /* lets now find the annotations in the field that are targeted to record components and append them to
3171 * the corresponding record component
3172 */
3173 ClassSymbol recordClass = (ClassSymbol) s.owner;
3174 RecordComponent rc = recordClass.getRecordComponent((VarSymbol)s);
3175 SymbolMetadata metadata = rc.getMetadata();
3176 if (metadata == null || metadata.isEmpty()) {
3177 /* if not is empty then we have already been here, which is the case if multiple annotations are applied
3178 * to the record component declaration
3179 */
3180 rc.appendAttributes(s.getRawAttributes().stream().filter(anno ->
3181 Arrays.stream(getTargetNames(anno.type.tsym)).anyMatch(name -> name == names.RECORD_COMPONENT)
3182 ).collect(List.collector()));
3183
3184 JCVariableDecl fieldAST = (JCVariableDecl) declarationTree;
3185 for (JCAnnotation fieldAnnot : fieldAST.mods.annotations) {
3186 for (JCAnnotation rcAnnot : rc.declarationFor().mods.annotations) {
3187 if (rcAnnot.pos == fieldAnnot.pos) {
3188 rcAnnot.setType(fieldAnnot.type);
3189 break;
3190 }
3191 }
3192 }
3193
3194 /* At this point, we used to carry over any type annotations from the VARDEF to the record component, but
3195 * that is problematic, since we get here only when *some* annotation is applied to the SE5 (declaration)
3196 * annotation location, inadvertently failing to carry over the type annotations when the VarDef has no
3197 * annotations in the SE5 annotation location.
3198 *
3199 * Now type annotations are assigned to record components in a method that would execute irrespective of
3200 * whether there are SE5 annotations on a VarDef viz com.sun.tools.javac.code.TypeAnnotations.TypeAnnotationPositions.visitVarDef
3201 */
3202 }
3203 }
3204 }
3205
3206 /* the section below is tricky. Annotations applied to record components are propagated to the corresponding
3207 * record member so if an annotation has target: FIELD, it is propagated to the corresponding FIELD, if it has
3208 * target METHOD, it is propagated to the accessor and so on. But at the moment when method members are generated
3209 * there is no enough information to propagate only the right annotations. So all the annotations are propagated
3210 * to all the possible locations.
3211 *
3212 * At this point we need to remove all the annotations that are not in place before going on with the annotation
3213 * party. On top of the above there is the issue that there is no AST representing record components, just symbols
3214 * so the corresponding field has been holding all the annotations and it's metadata has been modified as if it
3215 * was both a field and a record component.
3216 *
3217 * So there are two places where we need to trim annotations from: the metadata of the symbol and / or the modifiers
3218 * in the AST. Whatever is in the metadata will be written to the class file, whatever is in the modifiers could
3219 * be see by annotation processors.
3220 *
3221 * The metadata contains both type annotations and declaration annotations. At this point of the game we don't
3222 * need to care about type annotations, they are all in the right place. But we could need to remove declaration
3223 * annotations. So for declaration annotations if they are not applicable to the record member, excluding type
3224 * annotations which are already correct, then we will remove it. For the AST modifiers if the annotation is not
3225 * applicable either as type annotation and or declaration annotation, only in that case it will be removed.
3226 *
3227 * So it could be that annotation is removed as a declaration annotation but it is kept in the AST modifier for
3228 * further inspection by annotation processors.
3229 *
3230 * For example:
3231 *
3232 * import java.lang.annotation.*;
3233 *
3234 * @Target({ElementType.TYPE_USE, ElementType.RECORD_COMPONENT})
3235 * @Retention(RetentionPolicy.RUNTIME)
3236 * @interface Anno { }
3237 *
3238 * record R(@Anno String s) {}
3239 *
3240 * at this point we will have for the case of the generated field:
3241 * - @Anno in the modifier
3242 * - @Anno as a type annotation
3243 * - @Anno as a declaration annotation
3244 *
3245 * the last one should be removed because the annotation has not FIELD as target but it was applied as a
3246 * declaration annotation because the field was being treated both as a field and as a record component
3247 * as we have already copied the annotations to the record component, now the field doesn't need to hold
3248 * annotations that are not intended for it anymore. Still @Anno has to be kept in the AST's modifiers as it
3249 * is applicable as a type annotation to the type of the field.
3250 */
3251
3252 if (a.type.tsym.isAnnotationType()) {
3253 Optional<Set<Name>> applicableTargetsOp = getApplicableTargets(a, s);
3254 if (!applicableTargetsOp.isEmpty()) {
3255 Set<Name> applicableTargets = applicableTargetsOp.get();
3256 boolean notApplicableOrIsTypeUseOnly = applicableTargets.isEmpty() ||
3257 applicableTargets.size() == 1 && applicableTargets.contains(names.TYPE_USE);
3258 boolean isCompGeneratedRecordElement = isRecordMember && (s.flags_field & Flags.GENERATED_MEMBER) != 0;
3259 boolean isCompRecordElementWithNonApplicableDeclAnno = isCompGeneratedRecordElement && notApplicableOrIsTypeUseOnly;
3260
3261 if (applicableTargets.isEmpty() || isCompRecordElementWithNonApplicableDeclAnno) {
3262 if (isCompRecordElementWithNonApplicableDeclAnno) {
3263 /* so we have found an annotation that is not applicable to a record member that was generated by the
3264 * compiler. This was intentionally done at TypeEnter, now is the moment strip away the annotations
3265 * that are not applicable to the given record member
3266 */
3267 JCModifiers modifiers = TreeInfo.getModifiers(declarationTree);
3268 /* lets first remove the annotation from the modifier if it is not applicable, we have to check again as
3269 * it could be a type annotation
3270 */
3271 if (modifiers != null && applicableTargets.isEmpty()) {
3272 ListBuffer<JCAnnotation> newAnnotations = new ListBuffer<>();
3273 for (JCAnnotation anno : modifiers.annotations) {
3274 if (anno != a) {
3275 newAnnotations.add(anno);
3276 }
3277 }
3278 modifiers.annotations = newAnnotations.toList();
3279 }
3280 // now lets remove it from the symbol
3281 s.getMetadata().removeDeclarationMetadata(a.attribute);
3282 } else {
3283 log.error(a.pos(), Errors.AnnotationTypeNotApplicable);
3284 }
3285 }
3286 /* if we are seeing the @SafeVarargs annotation applied to a compiler generated accessor,
3287 * then this is an error as we know that no compiler generated accessor will be a varargs
3288 * method, better to fail asap
3289 */
3290 if (isCompGeneratedRecordElement && !isRecordField && a.type.tsym == syms.trustMeType.tsym && declarationTree.hasTag(METHODDEF)) {
3291 log.error(a.pos(), Errors.VarargsInvalidTrustmeAnno(syms.trustMeType.tsym, Fragments.VarargsTrustmeOnNonVarargsAccessor(s)));
3292 }
3293 }
3294 }
3295
3296 if (a.annotationType.type.tsym == syms.functionalInterfaceType.tsym) {
3297 if (s.kind != TYP) {
3298 log.error(a.pos(), Errors.BadFunctionalIntfAnno);
3299 } else if (!s.isInterface() || (s.flags() & ANNOTATION) != 0) {
3300 log.error(a.pos(), Errors.BadFunctionalIntfAnno1(Fragments.NotAFunctionalIntf(s)));
3301 }
3302 }
3303 }
3304
3305 public void validateTypeAnnotation(JCAnnotation a, Symbol s, boolean isTypeParameter) {
3306 Assert.checkNonNull(a.type);
3307 // we just want to validate that the anotation doesn't have any wrong target
3308 if (s != null) getApplicableTargets(a, s);
3309 validateAnnotationTree(a);
3310
3311 if (a.hasTag(TYPE_ANNOTATION) &&
3312 !a.annotationType.type.isErroneous() &&
3313 !isTypeAnnotation(a, isTypeParameter)) {
3314 log.error(a.pos(), Errors.AnnotationTypeNotApplicableToType(a.type));
3315 }
3316 }
3317
3318 /**
3319 * Validate the proposed container 'repeatable' on the
3320 * annotation type symbol 's'. Report errors at position
3321 * 'pos'.
3322 *
3323 * @param s The (annotation)type declaration annotated with a @Repeatable
3324 * @param repeatable the @Repeatable on 's'
3325 * @param pos where to report errors
3326 */
3327 public void validateRepeatable(TypeSymbol s, Attribute.Compound repeatable, DiagnosticPosition pos) {
3328 Assert.check(types.isSameType(repeatable.type, syms.repeatableType));
3329
3330 Type t = null;
3331 List<Pair<MethodSymbol,Attribute>> l = repeatable.values;
3332 if (!l.isEmpty()) {
3333 Assert.check(l.head.fst.name == names.value);
3334 if (l.head.snd instanceof Attribute.Class) {
3335 t = ((Attribute.Class)l.head.snd).getValue();
3336 }
3337 }
3338
3339 if (t == null) {
3340 // errors should already have been reported during Annotate
3341 return;
3342 }
3343
3344 validateValue(t.tsym, s, pos);
3345 validateRetention(t.tsym, s, pos);
3346 validateDocumented(t.tsym, s, pos);
3347 validateInherited(t.tsym, s, pos);
3348 validateTarget(t.tsym, s, pos);
3349 validateDefault(t.tsym, pos);
3350 }
3351
3352 private void validateValue(TypeSymbol container, TypeSymbol contained, DiagnosticPosition pos) {
3353 Symbol sym = container.members().findFirst(names.value);
3354 if (sym != null && sym.kind == MTH) {
3355 MethodSymbol m = (MethodSymbol) sym;
3356 Type ret = m.getReturnType();
3357 if (!(ret.hasTag(ARRAY) && types.isSameType(((ArrayType)ret).elemtype, contained.type))) {
3358 log.error(pos,
3359 Errors.InvalidRepeatableAnnotationValueReturn(container,
3360 ret,
3361 types.makeArrayType(contained.type)));
3362 }
3363 } else {
3364 log.error(pos, Errors.InvalidRepeatableAnnotationNoValue(container));
3365 }
3366 }
3367
3368 private void validateRetention(TypeSymbol container, TypeSymbol contained, DiagnosticPosition pos) {
3369 Attribute.RetentionPolicy containerRetention = types.getRetention(container);
3370 Attribute.RetentionPolicy containedRetention = types.getRetention(contained);
3371
3372 boolean error = false;
3373 switch (containedRetention) {
3374 case RUNTIME:
3375 if (containerRetention != Attribute.RetentionPolicy.RUNTIME) {
3376 error = true;
3377 }
3378 break;
3379 case CLASS:
3380 if (containerRetention == Attribute.RetentionPolicy.SOURCE) {
3381 error = true;
3382 }
3383 }
3384 if (error ) {
3385 log.error(pos,
3386 Errors.InvalidRepeatableAnnotationRetention(container,
3387 containerRetention.name(),
3388 contained,
3389 containedRetention.name()));
3390 }
3391 }
3392
3393 private void validateDocumented(Symbol container, Symbol contained, DiagnosticPosition pos) {
3394 if (contained.attribute(syms.documentedType.tsym) != null) {
3395 if (container.attribute(syms.documentedType.tsym) == null) {
3396 log.error(pos, Errors.InvalidRepeatableAnnotationNotDocumented(container, contained));
3397 }
3398 }
3399 }
3400
3401 private void validateInherited(Symbol container, Symbol contained, DiagnosticPosition pos) {
3402 if (contained.attribute(syms.inheritedType.tsym) != null) {
3403 if (container.attribute(syms.inheritedType.tsym) == null) {
3404 log.error(pos, Errors.InvalidRepeatableAnnotationNotInherited(container, contained));
3405 }
3406 }
3407 }
3408
3409 private void validateTarget(TypeSymbol container, TypeSymbol contained, DiagnosticPosition pos) {
3410 // The set of targets the container is applicable to must be a subset
3411 // (with respect to annotation target semantics) of the set of targets
3412 // the contained is applicable to. The target sets may be implicit or
3413 // explicit.
3414
3415 Set<Name> containerTargets;
3416 Attribute.Array containerTarget = getAttributeTargetAttribute(container);
3417 if (containerTarget == null) {
3418 containerTargets = getDefaultTargetSet();
3419 } else {
3420 containerTargets = new HashSet<>();
3421 for (Attribute app : containerTarget.values) {
3422 if (!(app instanceof Attribute.Enum attributeEnum)) {
3423 continue; // recovery
3424 }
3425 containerTargets.add(attributeEnum.value.name);
3426 }
3427 }
3428
3429 Set<Name> containedTargets;
3430 Attribute.Array containedTarget = getAttributeTargetAttribute(contained);
3431 if (containedTarget == null) {
3432 containedTargets = getDefaultTargetSet();
3433 } else {
3434 containedTargets = new HashSet<>();
3435 for (Attribute app : containedTarget.values) {
3436 if (!(app instanceof Attribute.Enum attributeEnum)) {
3437 continue; // recovery
3438 }
3439 containedTargets.add(attributeEnum.value.name);
3440 }
3441 }
3442
3443 if (!isTargetSubsetOf(containerTargets, containedTargets)) {
3444 log.error(pos, Errors.InvalidRepeatableAnnotationIncompatibleTarget(container, contained));
3445 }
3446 }
3447
3448 /* get a set of names for the default target */
3449 private Set<Name> getDefaultTargetSet() {
3450 if (defaultTargets == null) {
3451 defaultTargets = Set.of(defaultTargetMetaInfo());
3452 }
3453
3454 return defaultTargets;
3455 }
3456 private Set<Name> defaultTargets;
3457
3458
3459 /** Checks that s is a subset of t, with respect to ElementType
3460 * semantics, specifically {ANNOTATION_TYPE} is a subset of {TYPE},
3461 * and {TYPE_USE} covers the set {ANNOTATION_TYPE, TYPE, TYPE_USE,
3462 * TYPE_PARAMETER}.
3463 */
3464 private boolean isTargetSubsetOf(Set<Name> s, Set<Name> t) {
3465 // Check that all elements in s are present in t
3466 for (Name n2 : s) {
3467 boolean currentElementOk = false;
3468 for (Name n1 : t) {
3469 if (n1 == n2) {
3470 currentElementOk = true;
3471 break;
3472 } else if (n1 == names.TYPE && n2 == names.ANNOTATION_TYPE) {
3473 currentElementOk = true;
3474 break;
3475 } else if (n1 == names.TYPE_USE &&
3476 (n2 == names.TYPE ||
3477 n2 == names.ANNOTATION_TYPE ||
3478 n2 == names.TYPE_PARAMETER)) {
3479 currentElementOk = true;
3480 break;
3481 }
3482 }
3483 if (!currentElementOk)
3484 return false;
3485 }
3486 return true;
3487 }
3488
3489 private void validateDefault(Symbol container, DiagnosticPosition pos) {
3490 // validate that all other elements of containing type has defaults
3491 Scope scope = container.members();
3492 for(Symbol elm : scope.getSymbols()) {
3493 if (elm.name != names.value &&
3494 elm.kind == MTH &&
3495 ((MethodSymbol)elm).defaultValue == null) {
3496 log.error(pos,
3497 Errors.InvalidRepeatableAnnotationElemNondefault(container, elm));
3498 }
3499 }
3500 }
3501
3502 /** Is s a method symbol that overrides a method in a superclass? */
3503 boolean isOverrider(Symbol s) {
3504 if (s.kind != MTH || s.isStatic())
3505 return false;
3506 MethodSymbol m = (MethodSymbol)s;
3507 TypeSymbol owner = (TypeSymbol)m.owner;
3508 for (Type sup : types.closure(owner.type)) {
3509 if (sup == owner.type)
3510 continue; // skip "this"
3511 Scope scope = sup.tsym.members();
3512 for (Symbol sym : scope.getSymbolsByName(m.name)) {
3513 if (!sym.isStatic() && m.overrides(sym, owner, types, true))
3514 return true;
3515 }
3516 }
3517 return false;
3518 }
3519
3520 /** Is the annotation applicable to types? */
3521 protected boolean isTypeAnnotation(JCAnnotation a, boolean isTypeParameter) {
3522 List<Attribute> targets = typeAnnotations.annotationTargets(a.annotationType.type.tsym);
3523 return (targets == null) ?
3524 (Feature.NO_TARGET_ANNOTATION_APPLICABILITY.allowedInSource(source) && isTypeParameter) :
3525 targets.stream()
3526 .anyMatch(attr -> isTypeAnnotation(attr, isTypeParameter));
3527 }
3528 //where
3529 boolean isTypeAnnotation(Attribute a, boolean isTypeParameter) {
3530 Attribute.Enum e = (Attribute.Enum)a;
3531 return (e.value.name == names.TYPE_USE ||
3532 (isTypeParameter && e.value.name == names.TYPE_PARAMETER));
3533 }
3534
3535 /** Is the annotation applicable to the symbol? */
3536 Name[] getTargetNames(JCAnnotation a) {
3537 return getTargetNames(a.annotationType.type.tsym);
3538 }
3539
3540 public Name[] getTargetNames(TypeSymbol annoSym) {
3541 Attribute.Array arr = getAttributeTargetAttribute(annoSym);
3542 Name[] targets;
3543 if (arr == null) {
3544 targets = defaultTargetMetaInfo();
3545 } else {
3546 // TODO: can we optimize this?
3547 targets = new Name[arr.values.length];
3548 for (int i=0; i<arr.values.length; ++i) {
3549 Attribute app = arr.values[i];
3550 if (!(app instanceof Attribute.Enum attributeEnum)) {
3551 return new Name[0];
3552 }
3553 targets[i] = attributeEnum.value.name;
3554 }
3555 }
3556 return targets;
3557 }
3558
3559 boolean annotationApplicable(JCAnnotation a, Symbol s) {
3560 Optional<Set<Name>> targets = getApplicableTargets(a, s);
3561 /* the optional could be empty if the annotation is unknown in that case
3562 * we return that it is applicable and if it is erroneous that should imply
3563 * an error at the declaration site
3564 */
3565 return targets.isEmpty() || targets.isPresent() && !targets.get().isEmpty();
3566 }
3567
3568 Optional<Set<Name>> getApplicableTargets(JCAnnotation a, Symbol s) {
3569 Attribute.Array arr = getAttributeTargetAttribute(a.annotationType.type.tsym);
3570 Name[] targets;
3571 Set<Name> applicableTargets = new HashSet<>();
3572
3573 if (arr == null) {
3574 targets = defaultTargetMetaInfo();
3575 } else {
3576 // TODO: can we optimize this?
3577 targets = new Name[arr.values.length];
3578 for (int i=0; i<arr.values.length; ++i) {
3579 Attribute app = arr.values[i];
3580 if (!(app instanceof Attribute.Enum attributeEnum)) {
3581 // recovery
3582 return Optional.empty();
3583 }
3584 targets[i] = attributeEnum.value.name;
3585 }
3586 }
3587 for (Name target : targets) {
3588 if (target == names.TYPE) {
3589 if (s.kind == TYP)
3590 applicableTargets.add(names.TYPE);
3591 } else if (target == names.FIELD) {
3592 if (s.kind == VAR && s.owner.kind != MTH)
3593 applicableTargets.add(names.FIELD);
3594 } else if (target == names.RECORD_COMPONENT) {
3595 if (s.getKind() == ElementKind.RECORD_COMPONENT) {
3596 applicableTargets.add(names.RECORD_COMPONENT);
3597 }
3598 } else if (target == names.METHOD) {
3599 if (s.kind == MTH && !s.isConstructor())
3600 applicableTargets.add(names.METHOD);
3601 } else if (target == names.PARAMETER) {
3602 if (s.kind == VAR &&
3603 (s.owner.kind == MTH && (s.flags() & PARAMETER) != 0)) {
3604 applicableTargets.add(names.PARAMETER);
3605 }
3606 } else if (target == names.CONSTRUCTOR) {
3607 if (s.kind == MTH && s.isConstructor())
3608 applicableTargets.add(names.CONSTRUCTOR);
3609 } else if (target == names.LOCAL_VARIABLE) {
3610 if (s.kind == VAR && s.owner.kind == MTH &&
3611 (s.flags() & PARAMETER) == 0) {
3612 applicableTargets.add(names.LOCAL_VARIABLE);
3613 }
3614 } else if (target == names.ANNOTATION_TYPE) {
3615 if (s.kind == TYP && (s.flags() & ANNOTATION) != 0) {
3616 applicableTargets.add(names.ANNOTATION_TYPE);
3617 }
3618 } else if (target == names.PACKAGE) {
3619 if (s.kind == PCK)
3620 applicableTargets.add(names.PACKAGE);
3621 } else if (target == names.TYPE_USE) {
3622 if (s.kind == VAR &&
3623 (s.flags() & Flags.VAR_VARIABLE) != 0 &&
3624 (!Feature.TYPE_ANNOTATIONS_ON_VAR_LAMBDA_PARAMETER.allowedInSource(source) ||
3625 ((s.flags() & Flags.LAMBDA_PARAMETER) == 0))) {
3626 //cannot type annotate implicitly typed locals
3627 continue;
3628 } else if (s.kind == TYP || s.kind == VAR ||
3629 (s.kind == MTH && !s.isConstructor() &&
3630 !s.type.getReturnType().hasTag(VOID)) ||
3631 (s.kind == MTH && s.isConstructor())) {
3632 applicableTargets.add(names.TYPE_USE);
3633 }
3634 } else if (target == names.TYPE_PARAMETER) {
3635 if (s.kind == TYP && s.type.hasTag(TYPEVAR))
3636 applicableTargets.add(names.TYPE_PARAMETER);
3637 } else if (target == names.MODULE) {
3638 if (s.kind == MDL)
3639 applicableTargets.add(names.MODULE);
3640 } else {
3641 log.error(a, Errors.AnnotationUnrecognizedAttributeName(a.type, target));
3642 return Optional.empty(); // Unknown ElementType
3643 }
3644 }
3645 return Optional.of(applicableTargets);
3646 }
3647
3648 Attribute.Array getAttributeTargetAttribute(TypeSymbol s) {
3649 Attribute.Compound atTarget = s.getAnnotationTypeMetadata().getTarget();
3650 if (atTarget == null) return null; // ok, is applicable
3651 Attribute atValue = atTarget.member(names.value);
3652 return (atValue instanceof Attribute.Array attributeArray) ? attributeArray : null;
3653 }
3654
3655 private Name[] dfltTargetMeta;
3656 private Name[] defaultTargetMetaInfo() {
3657 if (dfltTargetMeta == null) {
3658 ArrayList<Name> defaultTargets = new ArrayList<>();
3659 defaultTargets.add(names.PACKAGE);
3660 defaultTargets.add(names.TYPE);
3661 defaultTargets.add(names.FIELD);
3662 defaultTargets.add(names.METHOD);
3663 defaultTargets.add(names.CONSTRUCTOR);
3664 defaultTargets.add(names.ANNOTATION_TYPE);
3665 defaultTargets.add(names.LOCAL_VARIABLE);
3666 defaultTargets.add(names.PARAMETER);
3667 if (allowRecords) {
3668 defaultTargets.add(names.RECORD_COMPONENT);
3669 }
3670 if (allowModules) {
3671 defaultTargets.add(names.MODULE);
3672 }
3673 dfltTargetMeta = defaultTargets.toArray(new Name[0]);
3674 }
3675 return dfltTargetMeta;
3676 }
3677
3678 /** Check an annotation value.
3679 *
3680 * @param a The annotation tree to check
3681 * @return true if this annotation tree is valid, otherwise false
3682 */
3683 public boolean validateAnnotationDeferErrors(JCAnnotation a) {
3684 boolean res = false;
3685 final Log.DiagnosticHandler diagHandler = log.new DiscardDiagnosticHandler();
3686 try {
3687 res = validateAnnotation(a);
3688 } finally {
3689 log.popDiagnosticHandler(diagHandler);
3690 }
3691 return res;
3692 }
3693
3694 private boolean validateAnnotation(JCAnnotation a) {
3695 boolean isValid = true;
3696 AnnotationTypeMetadata metadata = a.annotationType.type.tsym.getAnnotationTypeMetadata();
3697
3698 // collect an inventory of the annotation elements
3699 Set<MethodSymbol> elements = metadata.getAnnotationElements();
3700
3701 // remove the ones that are assigned values
3702 for (JCTree arg : a.args) {
3703 if (!arg.hasTag(ASSIGN)) continue; // recovery
3704 JCAssign assign = (JCAssign)arg;
3705 Symbol m = TreeInfo.symbol(assign.lhs);
3706 if (m == null || m.type.isErroneous()) continue;
3707 if (!elements.remove(m)) {
3708 isValid = false;
3709 log.error(assign.lhs.pos(),
3710 Errors.DuplicateAnnotationMemberValue(m.name, a.type));
3711 }
3712 }
3713
3714 // all the remaining ones better have default values
3715 List<Name> missingDefaults = List.nil();
3716 Set<MethodSymbol> membersWithDefault = metadata.getAnnotationElementsWithDefault();
3717 for (MethodSymbol m : elements) {
3718 if (m.type.isErroneous())
3719 continue;
3720
3721 if (!membersWithDefault.contains(m))
3722 missingDefaults = missingDefaults.append(m.name);
3723 }
3724 missingDefaults = missingDefaults.reverse();
3725 if (missingDefaults.nonEmpty()) {
3726 isValid = false;
3727 Error errorKey = (missingDefaults.size() > 1)
3728 ? Errors.AnnotationMissingDefaultValue1(a.type, missingDefaults)
3729 : Errors.AnnotationMissingDefaultValue(a.type, missingDefaults);
3730 log.error(a.pos(), errorKey);
3731 }
3732
3733 return isValid && validateTargetAnnotationValue(a);
3734 }
3735
3736 /* Validate the special java.lang.annotation.Target annotation */
3737 boolean validateTargetAnnotationValue(JCAnnotation a) {
3738 // special case: java.lang.annotation.Target must not have
3739 // repeated values in its value member
3740 if (a.annotationType.type.tsym != syms.annotationTargetType.tsym ||
3741 a.args.tail == null)
3742 return true;
3743
3744 boolean isValid = true;
3745 if (!a.args.head.hasTag(ASSIGN)) return false; // error recovery
3746 JCAssign assign = (JCAssign) a.args.head;
3747 Symbol m = TreeInfo.symbol(assign.lhs);
3748 if (m.name != names.value) return false;
3749 JCTree rhs = assign.rhs;
3750 if (!rhs.hasTag(NEWARRAY)) return false;
3751 JCNewArray na = (JCNewArray) rhs;
3752 Set<Symbol> targets = new HashSet<>();
3753 for (JCTree elem : na.elems) {
3754 if (!targets.add(TreeInfo.symbol(elem))) {
3755 isValid = false;
3756 log.error(elem.pos(), Errors.RepeatedAnnotationTarget);
3757 }
3758 }
3759 return isValid;
3760 }
3761
3762 void checkDeprecatedAnnotation(DiagnosticPosition pos, Symbol s) {
3763 if (lint.isEnabled(LintCategory.DEP_ANN) && s.isDeprecatableViaAnnotation() &&
3764 (s.flags() & DEPRECATED) != 0 &&
3765 !syms.deprecatedType.isErroneous() &&
3766 s.attribute(syms.deprecatedType.tsym) == null) {
3767 log.warning(pos, LintWarnings.MissingDeprecatedAnnotation);
3768 }
3769 // Note: @Deprecated has no effect on local variables, parameters and package decls.
3770 if (lint.isEnabled(LintCategory.DEPRECATION) && !s.isDeprecatableViaAnnotation() &&
3771 (s.flags() & RECORD) == 0 &&
3772 !syms.deprecatedType.isErroneous() &&
3773 s.attribute(syms.deprecatedType.tsym) != null) {
3774 log.warning(pos, LintWarnings.DeprecatedAnnotationHasNoEffect(Kinds.kindName(s)));
3775 }
3776 }
3777
3778 void checkDeprecated(final DiagnosticPosition pos, final Symbol other, final Symbol s) {
3779 checkDeprecated(() -> pos, other, s);
3780 }
3781
3782 void checkDeprecated(Supplier<DiagnosticPosition> pos, final Symbol other, final Symbol s) {
3783 if (!importSuppression
3784 && (s.isDeprecatedForRemoval() || s.isDeprecated() && !other.isDeprecated())
3785 && (s.outermostClass() != other.outermostClass() || s.outermostClass() == null)
3786 && s.kind != Kind.PCK) {
3787 warnDeprecated(pos.get(), s);
3788 }
3789 }
3790
3791 void checkSunAPI(final DiagnosticPosition pos, final Symbol s) {
3792 if ((s.flags() & PROPRIETARY) != 0) {
3793 log.warning(pos, Warnings.SunProprietary(s));
3794 }
3795 }
3796
3797 void checkProfile(final DiagnosticPosition pos, final Symbol s) {
3798 if (profile != Profile.DEFAULT && (s.flags() & NOT_IN_PROFILE) != 0) {
3799 log.error(pos, Errors.NotInProfile(s, profile));
3800 }
3801 }
3802
3803 void checkPreview(DiagnosticPosition pos, Symbol other, Symbol s) {
3804 checkPreview(pos, other, Type.noType, s);
3805 }
3806
3807 void checkPreview(DiagnosticPosition pos, Symbol other, Type site, Symbol s) {
3808 boolean sIsPreview;
3809 Symbol previewSymbol;
3810 if ((s.flags() & PREVIEW_API) != 0) {
3811 sIsPreview = true;
3812 previewSymbol= s;
3813 } else if ((s.kind == Kind.MTH || s.kind == Kind.VAR) &&
3814 site.tsym != null &&
3815 (site.tsym.flags() & PREVIEW_API) == 0 &&
3816 (s.owner.flags() & PREVIEW_API) != 0) {
3817 //calling a method, or using a field, whose owner is a preview, but
3818 //using a site that is not a preview. Also produce an error or warning:
3819 sIsPreview = true;
3820 previewSymbol = s.owner;
3821 } else {
3822 sIsPreview = false;
3823 previewSymbol = null;
3824 }
3825 if (sIsPreview && !preview.participatesInPreview(syms, other, s) && !disablePreviewCheck) {
3826 if ((previewSymbol.flags() & PREVIEW_REFLECTIVE) == 0) {
3827 if (!preview.isEnabled()) {
3828 log.error(pos, Errors.IsPreview(s));
3829 } else {
3830 preview.markUsesPreview(pos);
3831 warnPreviewAPI(pos, LintWarnings.IsPreview(s));
3832 }
3833 } else {
3834 warnPreviewAPI(pos, LintWarnings.IsPreviewReflective(s));
3835 }
3836 }
3837 if (preview.declaredUsingPreviewFeature(s)) {
3838 if (preview.isEnabled()) {
3839 //for preview disabled do presumably so not need to do anything?
3840 //If "s" is compiled from source, then there was an error for it already;
3841 //if "s" is from classfile, there already was an error for the classfile.
3842 preview.markUsesPreview(pos);
3843 warnPreviewAPI(pos, LintWarnings.DeclaredUsingPreview(kindName(s), s));
3844 }
3845 }
3846 }
3847
3848 void checkRestricted(DiagnosticPosition pos, Symbol s) {
3849 if (s.kind == MTH && (s.flags() & RESTRICTED) != 0) {
3850 log.warning(pos, LintWarnings.RestrictedMethod(s.enclClass(), s));
3851 }
3852 }
3853
3854 /* *************************************************************************
3855 * Check for recursive annotation elements.
3856 **************************************************************************/
3857
3858 /** Check for cycles in the graph of annotation elements.
3859 */
3860 void checkNonCyclicElements(JCClassDecl tree) {
3861 if ((tree.sym.flags_field & ANNOTATION) == 0) return;
3862 Assert.check((tree.sym.flags_field & LOCKED) == 0);
3863 try {
3864 tree.sym.flags_field |= LOCKED;
3865 for (JCTree def : tree.defs) {
3866 if (!def.hasTag(METHODDEF)) continue;
3867 JCMethodDecl meth = (JCMethodDecl)def;
3868 checkAnnotationResType(meth.pos(), meth.restype.type);
3869 }
3870 } finally {
3871 tree.sym.flags_field &= ~LOCKED;
3872 tree.sym.flags_field |= ACYCLIC_ANN;
3873 }
3874 }
3875
3876 void checkNonCyclicElementsInternal(DiagnosticPosition pos, TypeSymbol tsym) {
3877 if ((tsym.flags_field & ACYCLIC_ANN) != 0)
3878 return;
3879 if ((tsym.flags_field & LOCKED) != 0) {
3880 log.error(pos, Errors.CyclicAnnotationElement(tsym));
3881 return;
3882 }
3883 try {
3884 tsym.flags_field |= LOCKED;
3885 for (Symbol s : tsym.members().getSymbols(NON_RECURSIVE)) {
3886 if (s.kind != MTH)
3887 continue;
3888 checkAnnotationResType(pos, ((MethodSymbol)s).type.getReturnType());
3889 }
3890 } finally {
3891 tsym.flags_field &= ~LOCKED;
3892 tsym.flags_field |= ACYCLIC_ANN;
3893 }
3894 }
3895
3896 void checkAnnotationResType(DiagnosticPosition pos, Type type) {
3897 switch (type.getTag()) {
3898 case CLASS:
3899 if ((type.tsym.flags() & ANNOTATION) != 0)
3900 checkNonCyclicElementsInternal(pos, type.tsym);
3901 break;
3902 case ARRAY:
3903 checkAnnotationResType(pos, types.elemtype(type));
3904 break;
3905 default:
3906 break; // int etc
3907 }
3908 }
3909
3910 /* *************************************************************************
3911 * Check for cycles in the constructor call graph.
3912 **************************************************************************/
3913
3914 /** Check for cycles in the graph of constructors calling other
3915 * constructors.
3916 */
3917 void checkCyclicConstructors(JCClassDecl tree) {
3918 // use LinkedHashMap so we generate errors deterministically
3919 Map<Symbol,Symbol> callMap = new LinkedHashMap<>();
3920
3921 // enter each constructor this-call into the map
3922 for (List<JCTree> l = tree.defs; l.nonEmpty(); l = l.tail) {
3923 if (!TreeInfo.isConstructor(l.head))
3924 continue;
3925 JCMethodDecl meth = (JCMethodDecl)l.head;
3926 JCMethodInvocation app = TreeInfo.findConstructorCall(meth);
3927 if (app != null && TreeInfo.name(app.meth) == names._this) {
3928 callMap.put(meth.sym, TreeInfo.symbol(app.meth));
3929 } else {
3930 meth.sym.flags_field |= ACYCLIC;
3931 }
3932 }
3933
3934 // Check for cycles in the map
3935 Symbol[] ctors = new Symbol[0];
3936 ctors = callMap.keySet().toArray(ctors);
3937 for (Symbol caller : ctors) {
3938 checkCyclicConstructor(tree, caller, callMap);
3939 }
3940 }
3941
3942 /** Look in the map to see if the given constructor is part of a
3943 * call cycle.
3944 */
3945 private void checkCyclicConstructor(JCClassDecl tree, Symbol ctor,
3946 Map<Symbol,Symbol> callMap) {
3947 if (ctor != null && (ctor.flags_field & ACYCLIC) == 0) {
3948 if ((ctor.flags_field & LOCKED) != 0) {
3949 log.error(TreeInfo.diagnosticPositionFor(ctor, tree, false, t -> t.hasTag(IDENT)),
3950 Errors.RecursiveCtorInvocation);
3951 } else {
3952 ctor.flags_field |= LOCKED;
3953 checkCyclicConstructor(tree, callMap.remove(ctor), callMap);
3954 ctor.flags_field &= ~LOCKED;
3955 }
3956 ctor.flags_field |= ACYCLIC;
3957 }
3958 }
3959
3960 /* *************************************************************************
3961 * Verify the proper placement of super()/this() calls.
3962 *
3963 * - super()/this() may only appear in constructors
3964 * - There must be at most one super()/this() call per constructor
3965 * - The super()/this() call, if any, must be a top-level statement in the
3966 * constructor, i.e., not nested inside any other statement or block
3967 * - There must be no return statements prior to the super()/this() call
3968 **************************************************************************/
3969
3970 void checkSuperInitCalls(JCClassDecl tree) {
3971 new SuperThisChecker().check(tree);
3972 }
3973
3974 private class SuperThisChecker extends TreeScanner {
3975
3976 // Match this scan stack: 1=JCMethodDecl, 2=JCExpressionStatement, 3=JCMethodInvocation
3977 private static final int MATCH_SCAN_DEPTH = 3;
3978
3979 private boolean constructor; // is this method a constructor?
3980 private boolean firstStatement; // at the first statement in method?
3981 private JCReturn earlyReturn; // first return prior to the super()/init(), if any
3982 private Name initCall; // whichever of "super" or "init" we've seen already
3983 private int scanDepth; // current scan recursion depth in method body
3984
3985 public void check(JCClassDecl classDef) {
3986 scan(classDef.defs);
3987 }
3988
3989 @Override
3990 public void visitMethodDef(JCMethodDecl tree) {
3991 Assert.check(!constructor);
3992 Assert.check(earlyReturn == null);
3993 Assert.check(initCall == null);
3994 Assert.check(scanDepth == 1);
3995
3996 // Initialize state for this method
3997 constructor = TreeInfo.isConstructor(tree);
3998 try {
3999
4000 // Scan method body
4001 if (tree.body != null) {
4002 firstStatement = true;
4003 for (List<JCStatement> l = tree.body.stats; l.nonEmpty(); l = l.tail) {
4004 scan(l.head);
4005 firstStatement = false;
4006 }
4007 }
4008
4009 // Verify no 'return' seen prior to an explicit super()/this() call
4010 if (constructor && earlyReturn != null && initCall != null)
4011 log.error(earlyReturn.pos(), Errors.ReturnBeforeSuperclassInitialized);
4012 } finally {
4013 firstStatement = false;
4014 constructor = false;
4015 earlyReturn = null;
4016 initCall = null;
4017 }
4018 }
4019
4020 @Override
4021 public void scan(JCTree tree) {
4022 scanDepth++;
4023 try {
4024 super.scan(tree);
4025 } finally {
4026 scanDepth--;
4027 }
4028 }
4029
4030 @Override
4031 public void visitApply(JCMethodInvocation apply) {
4032 do {
4033
4034 // Is this a super() or this() call?
4035 Name methodName = TreeInfo.name(apply.meth);
4036 if (methodName != names._super && methodName != names._this)
4037 break;
4038
4039 // super()/this() calls must only appear in a constructor
4040 if (!constructor) {
4041 log.error(apply.pos(), Errors.CallMustOnlyAppearInCtor);
4042 break;
4043 }
4044
4045 // super()/this() calls must be a top level statement
4046 if (scanDepth != MATCH_SCAN_DEPTH) {
4047 log.error(apply.pos(), Errors.CtorCallsNotAllowedHere);
4048 break;
4049 }
4050
4051 // super()/this() calls must not appear more than once
4052 if (initCall != null) {
4053 log.error(apply.pos(), Errors.RedundantSuperclassInit);
4054 break;
4055 }
4056
4057 // If super()/this() isn't first, require flexible constructors feature
4058 if (!firstStatement)
4059 preview.checkSourceLevel(apply.pos(), Feature.FLEXIBLE_CONSTRUCTORS);
4060
4061 // We found a legitimate super()/this() call; remember it
4062 initCall = methodName;
4063 } while (false);
4064
4065 // Proceed
4066 super.visitApply(apply);
4067 }
4068
4069 @Override
4070 public void visitReturn(JCReturn tree) {
4071 if (constructor && initCall == null && earlyReturn == null)
4072 earlyReturn = tree; // we have seen a return but not (yet) a super()/this()
4073 super.visitReturn(tree);
4074 }
4075
4076 @Override
4077 public void visitClassDef(JCClassDecl tree) {
4078 // don't descend any further
4079 }
4080
4081 @Override
4082 public void visitLambda(JCLambda tree) {
4083 final boolean constructorPrev = constructor;
4084 final boolean firstStatementPrev = firstStatement;
4085 final JCReturn earlyReturnPrev = earlyReturn;
4086 final Name initCallPrev = initCall;
4087 final int scanDepthPrev = scanDepth;
4088 constructor = false;
4089 firstStatement = false;
4090 earlyReturn = null;
4091 initCall = null;
4092 scanDepth = 0;
4093 try {
4094 super.visitLambda(tree);
4095 } finally {
4096 constructor = constructorPrev;
4097 firstStatement = firstStatementPrev;
4098 earlyReturn = earlyReturnPrev;
4099 initCall = initCallPrev;
4100 scanDepth = scanDepthPrev;
4101 }
4102 }
4103 }
4104
4105 /* *************************************************************************
4106 * Miscellaneous
4107 **************************************************************************/
4108
4109 /**
4110 * Check for division by integer constant zero
4111 * @param pos Position for error reporting.
4112 * @param operator The operator for the expression
4113 * @param operand The right hand operand for the expression
4114 */
4115 void checkDivZero(final DiagnosticPosition pos, Symbol operator, Type operand) {
4116 if (operand.constValue() != null
4117 && operand.getTag().isSubRangeOf(LONG)
4118 && ((Number) (operand.constValue())).longValue() == 0) {
4119 int opc = ((OperatorSymbol)operator).opcode;
4120 if (opc == ByteCodes.idiv || opc == ByteCodes.imod
4121 || opc == ByteCodes.ldiv || opc == ByteCodes.lmod) {
4122 log.warning(pos, LintWarnings.DivZero);
4123 }
4124 }
4125 }
4126
4127 /**
4128 * Check for bit shifts using an out-of-range bit count.
4129 * @param pos Position for error reporting.
4130 * @param operator The operator for the expression
4131 * @param operand The right hand operand for the expression
4132 */
4133 void checkOutOfRangeShift(final DiagnosticPosition pos, Symbol operator, Type operand) {
4134 if (operand.constValue() instanceof Number shiftAmount) {
4135 Type targetType;
4136 int maximumShift;
4137 switch (((OperatorSymbol)operator).opcode) {
4138 case ByteCodes.ishl, ByteCodes.ishr, ByteCodes.iushr, ByteCodes.ishll, ByteCodes.ishrl, ByteCodes.iushrl -> {
4139 targetType = syms.intType;
4140 maximumShift = 0x1f;
4141 }
4142 case ByteCodes.lshl, ByteCodes.lshr, ByteCodes.lushr, ByteCodes.lshll, ByteCodes.lshrl, ByteCodes.lushrl -> {
4143 targetType = syms.longType;
4144 maximumShift = 0x3f;
4145 }
4146 default -> {
4147 return;
4148 }
4149 }
4150 long specifiedShift = shiftAmount.longValue();
4151 if (specifiedShift > maximumShift || specifiedShift < -maximumShift) {
4152 int actualShift = (int)specifiedShift & (maximumShift - 1);
4153 log.warning(pos, LintWarnings.BitShiftOutOfRange(targetType, specifiedShift, actualShift));
4154 }
4155 }
4156 }
4157
4158 /**
4159 * Check for possible loss of precission
4160 * @param pos Position for error reporting.
4161 * @param found The computed type of the tree
4162 * @param req The computed type of the tree
4163 */
4164 void checkLossOfPrecision(final DiagnosticPosition pos, Type found, Type req) {
4165 if (found.isNumeric() && req.isNumeric() && !types.isAssignable(found, req)) {
4166 log.warning(pos, LintWarnings.PossibleLossOfPrecision(found, req));
4167 }
4168 }
4169
4170 /**
4171 * Check for empty statements after if
4172 */
4173 void checkEmptyIf(JCIf tree) {
4174 if (tree.thenpart.hasTag(SKIP) && tree.elsepart == null) {
4175 log.warning(tree.thenpart.pos(), LintWarnings.EmptyIf);
4176 }
4177 }
4178
4179 /** Check that symbol is unique in given scope.
4180 * @param pos Position for error reporting.
4181 * @param sym The symbol.
4182 * @param s The scope.
4183 */
4184 boolean checkUnique(DiagnosticPosition pos, Symbol sym, Scope s) {
4185 if (sym.type.isErroneous())
4186 return true;
4187 if (sym.owner.name == names.any) return false;
4188 for (Symbol byName : s.getSymbolsByName(sym.name, NON_RECURSIVE)) {
4189 if (sym != byName &&
4190 (byName.flags() & CLASH) == 0 &&
4191 sym.kind == byName.kind &&
4192 sym.name != names.error &&
4193 (sym.kind != MTH ||
4194 types.hasSameArgs(sym.type, byName.type) ||
4195 types.hasSameArgs(types.erasure(sym.type), types.erasure(byName.type)))) {
4196 if ((sym.flags() & VARARGS) != (byName.flags() & VARARGS)) {
4197 sym.flags_field |= CLASH;
4198 varargsDuplicateError(pos, sym, byName);
4199 return true;
4200 } else if (sym.kind == MTH && !types.hasSameArgs(sym.type, byName.type, false)) {
4201 duplicateErasureError(pos, sym, byName);
4202 sym.flags_field |= CLASH;
4203 return true;
4204 } else if ((sym.flags() & MATCH_BINDING) != 0 &&
4205 (byName.flags() & MATCH_BINDING) != 0 &&
4206 (byName.flags() & MATCH_BINDING_TO_OUTER) == 0) {
4207 if (!sym.type.isErroneous()) {
4208 log.error(pos, Errors.MatchBindingExists);
4209 sym.flags_field |= CLASH;
4210 }
4211 return false;
4212 } else {
4213 duplicateError(pos, byName);
4214 return false;
4215 }
4216 }
4217 }
4218 return true;
4219 }
4220
4221 /** Report duplicate declaration error.
4222 */
4223 void duplicateErasureError(DiagnosticPosition pos, Symbol sym1, Symbol sym2) {
4224 if (!sym1.type.isErroneous() && !sym2.type.isErroneous()) {
4225 log.error(pos, Errors.NameClashSameErasure(sym1, sym2));
4226 }
4227 }
4228
4229 /**Check that types imported through the ordinary imports don't clash with types imported
4230 * by other (static or ordinary) imports. Note that two static imports may import two clashing
4231 * types without an error on the imports.
4232 * @param toplevel The toplevel tree for which the test should be performed.
4233 */
4234 void checkImportsUnique(JCCompilationUnit toplevel) {
4235 WriteableScope ordinallyImportedSoFar = WriteableScope.create(toplevel.packge);
4236 WriteableScope staticallyImportedSoFar = WriteableScope.create(toplevel.packge);
4237 WriteableScope topLevelScope = toplevel.toplevelScope;
4238
4239 for (JCTree def : toplevel.defs) {
4240 if (!def.hasTag(IMPORT))
4241 continue;
4242
4243 JCImport imp = (JCImport) def;
4244
4245 if (imp.importScope == null)
4246 continue;
4247
4248 for (Symbol sym : imp.importScope.getSymbols(sym -> sym.kind == TYP)) {
4249 if (imp.isStatic()) {
4250 checkUniqueImport(imp.pos(), ordinallyImportedSoFar, staticallyImportedSoFar, topLevelScope, sym, true);
4251 staticallyImportedSoFar.enter(sym);
4252 } else {
4253 checkUniqueImport(imp.pos(), ordinallyImportedSoFar, staticallyImportedSoFar, topLevelScope, sym, false);
4254 ordinallyImportedSoFar.enter(sym);
4255 }
4256 }
4257
4258 imp.importScope = null;
4259 }
4260 }
4261
4262 /** Check that single-type import is not already imported or top-level defined,
4263 * but make an exception for two single-type imports which denote the same type.
4264 * @param pos Position for error reporting.
4265 * @param ordinallyImportedSoFar A Scope containing types imported so far through
4266 * ordinary imports.
4267 * @param staticallyImportedSoFar A Scope containing types imported so far through
4268 * static imports.
4269 * @param topLevelScope The current file's top-level Scope
4270 * @param sym The symbol.
4271 * @param staticImport Whether or not this was a static import
4272 */
4273 private boolean checkUniqueImport(DiagnosticPosition pos, Scope ordinallyImportedSoFar,
4274 Scope staticallyImportedSoFar, Scope topLevelScope,
4275 Symbol sym, boolean staticImport) {
4276 Predicate<Symbol> duplicates = candidate -> candidate != sym && !candidate.type.isErroneous();
4277 Symbol ordinaryClashing = ordinallyImportedSoFar.findFirst(sym.name, duplicates);
4278 Symbol staticClashing = null;
4279 if (ordinaryClashing == null && !staticImport) {
4280 staticClashing = staticallyImportedSoFar.findFirst(sym.name, duplicates);
4281 }
4282 if (ordinaryClashing != null || staticClashing != null) {
4283 if (ordinaryClashing != null)
4284 log.error(pos, Errors.AlreadyDefinedSingleImport(ordinaryClashing));
4285 else
4286 log.error(pos, Errors.AlreadyDefinedStaticSingleImport(staticClashing));
4287 return false;
4288 }
4289 Symbol clashing = topLevelScope.findFirst(sym.name, duplicates);
4290 if (clashing != null) {
4291 log.error(pos, Errors.AlreadyDefinedThisUnit(clashing));
4292 return false;
4293 }
4294 return true;
4295 }
4296
4297 /** Check that a qualified name is in canonical form (for import decls).
4298 */
4299 public void checkCanonical(JCTree tree) {
4300 if (!isCanonical(tree))
4301 log.error(tree.pos(),
4302 Errors.ImportRequiresCanonical(TreeInfo.symbol(tree)));
4303 }
4304 // where
4305 private boolean isCanonical(JCTree tree) {
4306 while (tree.hasTag(SELECT)) {
4307 JCFieldAccess s = (JCFieldAccess) tree;
4308 if (s.sym.owner.getQualifiedName() != TreeInfo.symbol(s.selected).getQualifiedName())
4309 return false;
4310 tree = s.selected;
4311 }
4312 return true;
4313 }
4314
4315 /** Check that an auxiliary class is not accessed from any other file than its own.
4316 */
4317 void checkForBadAuxiliaryClassAccess(DiagnosticPosition pos, Env<AttrContext> env, ClassSymbol c) {
4318 if ((c.flags() & AUXILIARY) != 0 &&
4319 rs.isAccessible(env, c) &&
4320 !fileManager.isSameFile(c.sourcefile, env.toplevel.sourcefile))
4321 {
4322 log.warning(pos, LintWarnings.AuxiliaryClassAccessedFromOutsideOfItsSourceFile(c, c.sourcefile));
4323 }
4324 }
4325
4326 /**
4327 * Check for a default constructor in an exported package.
4328 */
4329 void checkDefaultConstructor(ClassSymbol c, DiagnosticPosition pos) {
4330 if (lint.isEnabled(LintCategory.MISSING_EXPLICIT_CTOR) &&
4331 ((c.flags() & (ENUM | RECORD)) == 0) &&
4332 !c.isAnonymous() &&
4333 ((c.flags() & (PUBLIC | PROTECTED)) != 0) &&
4334 Feature.MODULES.allowedInSource(source)) {
4335 NestingKind nestingKind = c.getNestingKind();
4336 switch (nestingKind) {
4337 case ANONYMOUS,
4338 LOCAL -> {return;}
4339 case TOP_LEVEL -> {;} // No additional checks needed
4340 case MEMBER -> {
4341 // For nested member classes, all the enclosing
4342 // classes must be public or protected.
4343 Symbol owner = c.owner;
4344 while (owner != null && owner.kind == TYP) {
4345 if ((owner.flags() & (PUBLIC | PROTECTED)) == 0)
4346 return;
4347 owner = owner.owner;
4348 }
4349 }
4350 }
4351
4352 // Only check classes in named packages exported by its module
4353 PackageSymbol pkg = c.packge();
4354 if (!pkg.isUnnamed()) {
4355 ModuleSymbol modle = pkg.modle;
4356 for (ExportsDirective exportDir : modle.exports) {
4357 // Report warning only if the containing
4358 // package is unconditionally exported
4359 if (exportDir.packge.equals(pkg)) {
4360 if (exportDir.modules == null || exportDir.modules.isEmpty()) {
4361 // Warning may be suppressed by
4362 // annotations; check again for being
4363 // enabled in the deferred context.
4364 log.warning(pos, LintWarnings.MissingExplicitCtor(c, pkg, modle));
4365 } else {
4366 return;
4367 }
4368 }
4369 }
4370 }
4371 }
4372 return;
4373 }
4374
4375 private class ConversionWarner extends Warner {
4376 final String uncheckedKey;
4377 final Type found;
4378 final Type expected;
4379 public ConversionWarner(DiagnosticPosition pos, String uncheckedKey, Type found, Type expected) {
4380 super(pos);
4381 this.uncheckedKey = uncheckedKey;
4382 this.found = found;
4383 this.expected = expected;
4384 }
4385
4386 @Override
4387 public void warn(LintCategory lint) {
4388 boolean warned = this.warned;
4389 super.warn(lint);
4390 if (warned) return; // suppress redundant diagnostics
4391 switch (lint) {
4392 case UNCHECKED:
4393 Check.this.warnUnchecked(pos(), LintWarnings.ProbFoundReq(diags.fragment(uncheckedKey), found, expected));
4394 break;
4395 case VARARGS:
4396 if (method != null &&
4397 method.attribute(syms.trustMeType.tsym) != null &&
4398 isTrustMeAllowedOnMethod(method) &&
4399 !types.isReifiable(method.type.getParameterTypes().last())) {
4400 log.warning(pos(), LintWarnings.VarargsUnsafeUseVarargsParam(method.params.last()));
4401 }
4402 break;
4403 default:
4404 throw new AssertionError("Unexpected lint: " + lint);
4405 }
4406 }
4407 }
4408
4409 public Warner castWarner(DiagnosticPosition pos, Type found, Type expected) {
4410 return new ConversionWarner(pos, "unchecked.cast.to.type", found, expected);
4411 }
4412
4413 public Warner convertWarner(DiagnosticPosition pos, Type found, Type expected) {
4414 return new ConversionWarner(pos, "unchecked.assign", found, expected);
4415 }
4416
4417 public void checkFunctionalInterface(JCClassDecl tree, ClassSymbol cs) {
4418 Compound functionalType = cs.attribute(syms.functionalInterfaceType.tsym);
4419
4420 if (functionalType != null) {
4421 try {
4422 types.findDescriptorSymbol((TypeSymbol)cs);
4423 } catch (Types.FunctionDescriptorLookupError ex) {
4424 DiagnosticPosition pos = tree.pos();
4425 for (JCAnnotation a : tree.getModifiers().annotations) {
4426 if (a.annotationType.type.tsym == syms.functionalInterfaceType.tsym) {
4427 pos = a.pos();
4428 break;
4429 }
4430 }
4431 log.error(pos, Errors.BadFunctionalIntfAnno1(ex.getDiagnostic()));
4432 }
4433 }
4434 }
4435
4436 public void checkImportsResolvable(final JCCompilationUnit toplevel) {
4437 for (final JCImportBase impBase : toplevel.getImports()) {
4438 if (!(impBase instanceof JCImport imp))
4439 continue;
4440 if (!imp.staticImport || !imp.qualid.hasTag(SELECT))
4441 continue;
4442 final JCFieldAccess select = imp.qualid;
4443 final Symbol origin;
4444 if (select.name == names.asterisk || (origin = TreeInfo.symbol(select.selected)) == null || origin.kind != TYP)
4445 continue;
4446
4447 TypeSymbol site = (TypeSymbol) TreeInfo.symbol(select.selected);
4448 if (!checkTypeContainsImportableElement(site, site, toplevel.packge, select.name, new HashSet<Symbol>())) {
4449 log.error(imp.pos(),
4450 Errors.CantResolveLocation(KindName.STATIC,
4451 select.name,
4452 null,
4453 null,
4454 Fragments.Location(kindName(site),
4455 site,
4456 null)));
4457 }
4458 }
4459 }
4460
4461 // Check that packages imported are in scope (JLS 7.4.3, 6.3, 6.5.3.1, 6.5.3.2)
4462 public void checkImportedPackagesObservable(final JCCompilationUnit toplevel) {
4463 OUTER: for (JCImportBase impBase : toplevel.getImports()) {
4464 if (impBase instanceof JCImport imp && !imp.staticImport &&
4465 TreeInfo.name(imp.qualid) == names.asterisk) {
4466 TypeSymbol tsym = imp.qualid.selected.type.tsym;
4467 if (tsym.kind == PCK && tsym.members().isEmpty() &&
4468 !(Feature.IMPORT_ON_DEMAND_OBSERVABLE_PACKAGES.allowedInSource(source) && tsym.exists())) {
4469 log.error(DiagnosticFlag.RESOLVE_ERROR, imp.qualid.selected.pos(), Errors.DoesntExist(tsym));
4470 }
4471 }
4472 }
4473 }
4474
4475 private boolean checkTypeContainsImportableElement(TypeSymbol tsym, TypeSymbol origin, PackageSymbol packge, Name name, Set<Symbol> processed) {
4476 if (tsym == null || !processed.add(tsym))
4477 return false;
4478
4479 // also search through inherited names
4480 if (checkTypeContainsImportableElement(types.supertype(tsym.type).tsym, origin, packge, name, processed))
4481 return true;
4482
4483 for (Type t : types.interfaces(tsym.type))
4484 if (checkTypeContainsImportableElement(t.tsym, origin, packge, name, processed))
4485 return true;
4486
4487 for (Symbol sym : tsym.members().getSymbolsByName(name)) {
4488 if (sym.isStatic() &&
4489 importAccessible(sym, packge) &&
4490 sym.isMemberOf(origin, types)) {
4491 return true;
4492 }
4493 }
4494
4495 return false;
4496 }
4497
4498 // is the sym accessible everywhere in packge?
4499 public boolean importAccessible(Symbol sym, PackageSymbol packge) {
4500 try {
4501 int flags = (int)(sym.flags() & AccessFlags);
4502 switch (flags) {
4503 default:
4504 case PUBLIC:
4505 return true;
4506 case PRIVATE:
4507 return false;
4508 case 0:
4509 case PROTECTED:
4510 return sym.packge() == packge;
4511 }
4512 } catch (ClassFinder.BadClassFile err) {
4513 throw err;
4514 } catch (CompletionFailure ex) {
4515 return false;
4516 }
4517 }
4518
4519 public void checkLeaksNotAccessible(Env<AttrContext> env, JCClassDecl check) {
4520 JCCompilationUnit toplevel = env.toplevel;
4521
4522 if ( toplevel.modle == syms.unnamedModule
4523 || toplevel.modle == syms.noModule
4524 || (check.sym.flags() & COMPOUND) != 0) {
4525 return ;
4526 }
4527
4528 ExportsDirective currentExport = findExport(toplevel.packge);
4529
4530 if ( currentExport == null //not exported
4531 || currentExport.modules != null) //don't check classes in qualified export
4532 return ;
4533
4534 new TreeScanner() {
4535 Lint lint = env.info.lint;
4536 boolean inSuperType;
4537
4538 @Override
4539 public void visitBlock(JCBlock tree) {
4540 }
4541 @Override
4542 public void visitMethodDef(JCMethodDecl tree) {
4543 if (!isAPISymbol(tree.sym))
4544 return;
4545 Lint prevLint = lint;
4546 try {
4547 lint = lint.augment(tree.sym);
4548 if (lint.isEnabled(LintCategory.EXPORTS)) {
4549 super.visitMethodDef(tree);
4550 }
4551 } finally {
4552 lint = prevLint;
4553 }
4554 }
4555 @Override
4556 public void visitVarDef(JCVariableDecl tree) {
4557 if (!isAPISymbol(tree.sym) && tree.sym.owner.kind != MTH)
4558 return;
4559 Lint prevLint = lint;
4560 try {
4561 lint = lint.augment(tree.sym);
4562 if (lint.isEnabled(LintCategory.EXPORTS)) {
4563 scan(tree.mods);
4564 scan(tree.vartype);
4565 }
4566 } finally {
4567 lint = prevLint;
4568 }
4569 }
4570 @Override
4571 public void visitClassDef(JCClassDecl tree) {
4572 if (tree != check)
4573 return ;
4574
4575 if (!isAPISymbol(tree.sym))
4576 return ;
4577
4578 Lint prevLint = lint;
4579 try {
4580 lint = lint.augment(tree.sym);
4581 if (lint.isEnabled(LintCategory.EXPORTS)) {
4582 scan(tree.mods);
4583 scan(tree.typarams);
4584 try {
4585 inSuperType = true;
4586 scan(tree.extending);
4587 scan(tree.implementing);
4588 } finally {
4589 inSuperType = false;
4590 }
4591 scan(tree.defs);
4592 }
4593 } finally {
4594 lint = prevLint;
4595 }
4596 }
4597 @Override
4598 public void visitTypeApply(JCTypeApply tree) {
4599 scan(tree.clazz);
4600 boolean oldInSuperType = inSuperType;
4601 try {
4602 inSuperType = false;
4603 scan(tree.arguments);
4604 } finally {
4605 inSuperType = oldInSuperType;
4606 }
4607 }
4608 @Override
4609 public void visitIdent(JCIdent tree) {
4610 Symbol sym = TreeInfo.symbol(tree);
4611 if (sym.kind == TYP && !sym.type.hasTag(TYPEVAR)) {
4612 checkVisible(tree.pos(), sym, toplevel.packge, inSuperType);
4613 }
4614 }
4615
4616 @Override
4617 public void visitSelect(JCFieldAccess tree) {
4618 Symbol sym = TreeInfo.symbol(tree);
4619 Symbol sitesym = TreeInfo.symbol(tree.selected);
4620 if (sym.kind == TYP && sitesym.kind == PCK) {
4621 checkVisible(tree.pos(), sym, toplevel.packge, inSuperType);
4622 } else {
4623 super.visitSelect(tree);
4624 }
4625 }
4626
4627 @Override
4628 public void visitAnnotation(JCAnnotation tree) {
4629 if (tree.attribute.type.tsym.getAnnotation(java.lang.annotation.Documented.class) != null)
4630 super.visitAnnotation(tree);
4631 }
4632
4633 }.scan(check);
4634 }
4635 //where:
4636 private ExportsDirective findExport(PackageSymbol pack) {
4637 for (ExportsDirective d : pack.modle.exports) {
4638 if (d.packge == pack)
4639 return d;
4640 }
4641
4642 return null;
4643 }
4644 private boolean isAPISymbol(Symbol sym) {
4645 while (sym.kind != PCK) {
4646 if ((sym.flags() & Flags.PUBLIC) == 0 && (sym.flags() & Flags.PROTECTED) == 0) {
4647 return false;
4648 }
4649 sym = sym.owner;
4650 }
4651 return true;
4652 }
4653 private void checkVisible(DiagnosticPosition pos, Symbol what, PackageSymbol inPackage, boolean inSuperType) {
4654 if (!isAPISymbol(what) && !inSuperType) { //package private/private element
4655 log.warning(pos, LintWarnings.LeaksNotAccessible(kindName(what), what, what.packge().modle));
4656 return ;
4657 }
4658
4659 PackageSymbol whatPackage = what.packge();
4660 ExportsDirective whatExport = findExport(whatPackage);
4661 ExportsDirective inExport = findExport(inPackage);
4662
4663 if (whatExport == null) { //package not exported:
4664 log.warning(pos, LintWarnings.LeaksNotAccessibleUnexported(kindName(what), what, what.packge().modle));
4665 return ;
4666 }
4667
4668 if (whatExport.modules != null) {
4669 if (inExport.modules == null || !whatExport.modules.containsAll(inExport.modules)) {
4670 log.warning(pos, LintWarnings.LeaksNotAccessibleUnexportedQualified(kindName(what), what, what.packge().modle));
4671 }
4672 }
4673
4674 if (whatPackage.modle != inPackage.modle && whatPackage.modle != syms.java_base) {
4675 //check that relativeTo.modle requires transitive what.modle, somehow:
4676 List<ModuleSymbol> todo = List.of(inPackage.modle);
4677
4678 while (todo.nonEmpty()) {
4679 ModuleSymbol current = todo.head;
4680 todo = todo.tail;
4681 if (current == whatPackage.modle)
4682 return ; //OK
4683 if ((current.flags() & Flags.AUTOMATIC_MODULE) != 0)
4684 continue; //for automatic modules, don't look into their dependencies
4685 for (RequiresDirective req : current.requires) {
4686 if (req.isTransitive()) {
4687 todo = todo.prepend(req.module);
4688 }
4689 }
4690 }
4691
4692 log.warning(pos, LintWarnings.LeaksNotAccessibleNotRequiredTransitive(kindName(what), what, what.packge().modle));
4693 }
4694 }
4695
4696 void checkModuleExists(final DiagnosticPosition pos, ModuleSymbol msym) {
4697 if (msym.kind != MDL) {
4698 log.warning(pos, LintWarnings.ModuleNotFound(msym));
4699 }
4700 }
4701
4702 void checkPackageExistsForOpens(final DiagnosticPosition pos, PackageSymbol packge) {
4703 if (packge.members().isEmpty() &&
4704 ((packge.flags() & Flags.HAS_RESOURCE) == 0)) {
4705 log.warning(pos, LintWarnings.PackageEmptyOrNotFound(packge));
4706 }
4707 }
4708
4709 void checkModuleRequires(final DiagnosticPosition pos, final RequiresDirective rd) {
4710 if ((rd.module.flags() & Flags.AUTOMATIC_MODULE) != 0) {
4711 if (rd.isTransitive()) { // see comment in Log.applyLint() for special logic that applies
4712 log.warning(pos, LintWarnings.RequiresTransitiveAutomatic);
4713 } else {
4714 log.warning(pos, LintWarnings.RequiresAutomatic);
4715 }
4716 }
4717 }
4718
4719 /**
4720 * Verify the case labels conform to the constraints. Checks constraints related
4721 * combinations of patterns and other labels.
4722 *
4723 * @param cases the cases that should be checked.
4724 */
4725 void checkSwitchCaseStructure(List<JCCase> cases) {
4726 for (List<JCCase> l = cases; l.nonEmpty(); l = l.tail) {
4727 JCCase c = l.head;
4728 if (c.labels.head instanceof JCConstantCaseLabel constLabel) {
4729 if (TreeInfo.isNull(constLabel.expr)) {
4730 if (c.labels.tail.nonEmpty()) {
4731 if (c.labels.tail.head instanceof JCDefaultCaseLabel defLabel) {
4732 if (c.labels.tail.tail.nonEmpty()) {
4733 log.error(c.labels.tail.tail.head.pos(), Errors.InvalidCaseLabelCombination);
4734 }
4735 } else {
4736 log.error(c.labels.tail.head.pos(), Errors.InvalidCaseLabelCombination);
4737 }
4738 }
4739 } else {
4740 for (JCCaseLabel label : c.labels.tail) {
4741 if (!(label instanceof JCConstantCaseLabel) || TreeInfo.isNullCaseLabel(label)) {
4742 log.error(label.pos(), Errors.InvalidCaseLabelCombination);
4743 break;
4744 }
4745 }
4746 }
4747 } else if (c.labels.tail.nonEmpty()) {
4748 var patterCaseLabels = c.labels.stream().filter(ll -> ll instanceof JCPatternCaseLabel).map(cl -> (JCPatternCaseLabel)cl);
4749 var allUnderscore = patterCaseLabels.allMatch(pcl -> !hasBindings(pcl.getPattern()));
4750
4751 if (!allUnderscore) {
4752 log.error(c.labels.tail.head.pos(), Errors.FlowsThroughFromPattern);
4753 }
4754
4755 boolean allPatternCaseLabels = c.labels.stream().allMatch(p -> p instanceof JCPatternCaseLabel);
4756
4757 if (allPatternCaseLabels) {
4758 preview.checkSourceLevel(c.labels.tail.head.pos(), Feature.UNNAMED_VARIABLES);
4759 }
4760
4761 for (JCCaseLabel label : c.labels.tail) {
4762 if (label instanceof JCConstantCaseLabel) {
4763 log.error(label.pos(), Errors.InvalidCaseLabelCombination);
4764 break;
4765 }
4766 }
4767 }
4768 }
4769
4770 boolean isCaseStatementGroup = cases.nonEmpty() &&
4771 cases.head.caseKind == CaseTree.CaseKind.STATEMENT;
4772
4773 if (isCaseStatementGroup) {
4774 boolean previousCompletessNormally = false;
4775 for (List<JCCase> l = cases; l.nonEmpty(); l = l.tail) {
4776 JCCase c = l.head;
4777 if (previousCompletessNormally &&
4778 c.stats.nonEmpty() &&
4779 c.labels.head instanceof JCPatternCaseLabel patternLabel &&
4780 (hasBindings(patternLabel.pat) || hasBindings(c.guard))) {
4781 log.error(c.labels.head.pos(), Errors.FlowsThroughToPattern);
4782 } else if (c.stats.isEmpty() &&
4783 c.labels.head instanceof JCPatternCaseLabel patternLabel &&
4784 (hasBindings(patternLabel.pat) || hasBindings(c.guard)) &&
4785 hasStatements(l.tail)) {
4786 log.error(c.labels.head.pos(), Errors.FlowsThroughFromPattern);
4787 }
4788 previousCompletessNormally = c.completesNormally;
4789 }
4790 }
4791 }
4792
4793 boolean hasBindings(JCTree p) {
4794 boolean[] bindings = new boolean[1];
4795
4796 new TreeScanner() {
4797 @Override
4798 public void visitBindingPattern(JCBindingPattern tree) {
4799 bindings[0] |= !tree.var.sym.isUnnamedVariable();
4800 super.visitBindingPattern(tree);
4801 }
4802 }.scan(p);
4803
4804 return bindings[0];
4805 }
4806
4807 boolean hasStatements(List<JCCase> cases) {
4808 for (List<JCCase> l = cases; l.nonEmpty(); l = l.tail) {
4809 if (l.head.stats.nonEmpty()) {
4810 return true;
4811 }
4812 }
4813
4814 return false;
4815 }
4816 void checkSwitchCaseLabelDominated(JCCaseLabel unconditionalCaseLabel, List<JCCase> cases) {
4817 List<Pair<JCCase, JCCaseLabel>> caseLabels = List.nil();
4818 boolean seenDefault = false;
4819 boolean seenDefaultLabel = false;
4820 boolean warnDominatedByDefault = false;
4821 boolean unconditionalFound = false;
4822
4823 for (List<JCCase> l = cases; l.nonEmpty(); l = l.tail) {
4824 JCCase c = l.head;
4825 for (JCCaseLabel label : c.labels) {
4826 if (label.hasTag(DEFAULTCASELABEL)) {
4827 seenDefault = true;
4828 seenDefaultLabel |=
4829 TreeInfo.isNullCaseLabel(c.labels.head);
4830 continue;
4831 }
4832 if (TreeInfo.isNullCaseLabel(label)) {
4833 if (seenDefault) {
4834 log.error(label.pos(), Errors.PatternDominated);
4835 }
4836 continue;
4837 }
4838 if (seenDefault && !warnDominatedByDefault) {
4839 if (label.hasTag(PATTERNCASELABEL) ||
4840 (label instanceof JCConstantCaseLabel && seenDefaultLabel)) {
4841 log.error(label.pos(), Errors.PatternDominated);
4842 warnDominatedByDefault = true;
4843 }
4844 }
4845 Type currentType = labelType(label);
4846 for (Pair<JCCase, JCCaseLabel> caseAndLabel : caseLabels) {
4847 JCCase testCase = caseAndLabel.fst;
4848 JCCaseLabel testCaseLabel = caseAndLabel.snd;
4849 Type testType = labelType(testCaseLabel);
4850
4851 // an unconditional pattern cannot be followed by any other label
4852 if (allowPrimitivePatterns && unconditionalCaseLabel == testCaseLabel && unconditionalCaseLabel != label) {
4853 log.error(label.pos(), Errors.PatternDominated);
4854 continue;
4855 }
4856
4857 boolean dominated = false;
4858 if (!currentType.hasTag(ERROR) && !testType.hasTag(ERROR)) {
4859 // the current label is potentially dominated by the existing (test) label, check:
4860 if (types.isUnconditionallyExactCombined(currentType, testType) &&
4861 label instanceof JCConstantCaseLabel) {
4862 dominated = !(testCaseLabel instanceof JCConstantCaseLabel) &&
4863 TreeInfo.unguardedCase(testCase);
4864 } else if (label instanceof JCPatternCaseLabel patternCL &&
4865 testCaseLabel instanceof JCPatternCaseLabel testPatternCaseLabel &&
4866 (testCase.equals(c) || TreeInfo.unguardedCase(testCase))) {
4867 dominated = patternDominated(testPatternCaseLabel.pat, patternCL.pat);
4868 }
4869 }
4870 if (dominated) {
4871 log.error(label.pos(), Errors.PatternDominated);
4872 }
4873 }
4874 caseLabels = caseLabels.prepend(Pair.of(c, label));
4875 }
4876 }
4877 }
4878 //where:
4879 private Type labelType(JCCaseLabel label) {
4880 return types.erasure(switch (label.getTag()) {
4881 case PATTERNCASELABEL -> ((JCPatternCaseLabel) label).pat.type;
4882 case CONSTANTCASELABEL -> ((JCConstantCaseLabel) label).expr.type;
4883 default -> throw Assert.error("Unexpected tree kind: " + label.getTag());
4884 });
4885 }
4886 private boolean patternDominated(JCPattern existingPattern, JCPattern currentPattern) {
4887 Type existingPatternType = types.erasure(existingPattern.type);
4888 Type currentPatternType = types.erasure(currentPattern.type);
4889 if (!types.isUnconditionallyExactTypeBased(currentPatternType, existingPatternType)) {
4890 return false;
4891 }
4892 if (currentPattern instanceof JCBindingPattern ||
4893 currentPattern instanceof JCAnyPattern) {
4894 return existingPattern instanceof JCBindingPattern ||
4895 existingPattern instanceof JCAnyPattern;
4896 } else if (currentPattern instanceof JCRecordPattern currentRecordPattern) {
4897 if (existingPattern instanceof JCBindingPattern ||
4898 existingPattern instanceof JCAnyPattern) {
4899 return true;
4900 } else if (existingPattern instanceof JCRecordPattern existingRecordPattern) {
4901 List<JCPattern> existingNested = existingRecordPattern.nested;
4902 List<JCPattern> currentNested = currentRecordPattern.nested;
4903 if (existingNested.size() != currentNested.size()) {
4904 return false;
4905 }
4906 while (existingNested.nonEmpty()) {
4907 if (!patternDominated(existingNested.head, currentNested.head)) {
4908 return false;
4909 }
4910 existingNested = existingNested.tail;
4911 currentNested = currentNested.tail;
4912 }
4913 return true;
4914 } else {
4915 Assert.error("Unknown pattern: " + existingPattern.getTag());
4916 }
4917 } else {
4918 Assert.error("Unknown pattern: " + currentPattern.getTag());
4919 }
4920 return false;
4921 }
4922
4923 /** check if a type is a subtype of Externalizable, if that is available. */
4924 boolean isExternalizable(Type t) {
4925 try {
4926 syms.externalizableType.complete();
4927 } catch (CompletionFailure e) {
4928 return false;
4929 }
4930 return types.isSubtype(t, syms.externalizableType);
4931 }
4932
4933 /**
4934 * Check structure of serialization declarations.
4935 */
4936 public void checkSerialStructure(Env<AttrContext> env, JCClassDecl tree, ClassSymbol c) {
4937 (new SerialTypeVisitor(env)).visit(c, tree);
4938 }
4939
4940 /**
4941 * This visitor will warn if a serialization-related field or
4942 * method is declared in a suspicious or incorrect way. In
4943 * particular, it will warn for cases where the runtime
4944 * serialization mechanism will silently ignore a mis-declared
4945 * entity.
4946 *
4947 * Distinguished serialization-related fields and methods:
4948 *
4949 * Methods:
4950 *
4951 * private void writeObject(ObjectOutputStream stream) throws IOException
4952 * ANY-ACCESS-MODIFIER Object writeReplace() throws ObjectStreamException
4953 *
4954 * private void readObject(ObjectInputStream stream) throws IOException, ClassNotFoundException
4955 * private void readObjectNoData() throws ObjectStreamException
4956 * ANY-ACCESS-MODIFIER Object readResolve() throws ObjectStreamException
4957 *
4958 * Fields:
4959 *
4960 * private static final long serialVersionUID
4961 * private static final ObjectStreamField[] serialPersistentFields
4962 *
4963 * Externalizable: methods defined on the interface
4964 * public void writeExternal(ObjectOutput) throws IOException
4965 * public void readExternal(ObjectInput) throws IOException
4966 */
4967 private class SerialTypeVisitor extends ElementKindVisitor14<Void, JCClassDecl> {
4968 Env<AttrContext> env;
4969 SerialTypeVisitor(Env<AttrContext> env) {
4970 this.lint = Check.this.lint;
4971 this.env = env;
4972 }
4973
4974 private static final Set<String> serialMethodNames =
4975 Set.of("writeObject", "writeReplace",
4976 "readObject", "readObjectNoData",
4977 "readResolve");
4978
4979 private static final Set<String> serialFieldNames =
4980 Set.of("serialVersionUID", "serialPersistentFields");
4981
4982 // Type of serialPersistentFields
4983 private final Type OSF_TYPE = new Type.ArrayType(syms.objectStreamFieldType, syms.arrayClass);
4984
4985 Lint lint;
4986
4987 @Override
4988 public Void defaultAction(Element e, JCClassDecl p) {
4989 throw new IllegalArgumentException(Objects.requireNonNullElse(e.toString(), ""));
4990 }
4991
4992 @Override
4993 public Void visitType(TypeElement e, JCClassDecl p) {
4994 runUnderLint(e, p, (symbol, param) -> super.visitType(symbol, param));
4995 return null;
4996 }
4997
4998 @Override
4999 public Void visitTypeAsClass(TypeElement e,
5000 JCClassDecl p) {
5001 // Anonymous classes filtered out by caller.
5002
5003 ClassSymbol c = (ClassSymbol)e;
5004
5005 checkCtorAccess(p, c);
5006
5007 /* Check for missing serialVersionUID; check *not* done
5008 * for enums or records.
5009 * Migrated value classes, need the value class and its corresponding
5010 * identity class to have the same SVUID.
5011 */
5012 VarSymbol svuidSym = null;
5013 for (Symbol sym : c.members().getSymbolsByName(names.serialVersionUID)) {
5014 if (sym.kind == VAR) {
5015 svuidSym = (VarSymbol)sym;
5016 break;
5017 }
5018 }
5019
5020 if (svuidSym == null) {
5021 log.warning(p.pos(), LintWarnings.MissingSVUID(c));
5022 }
5023
5024 // Check for serialPersistentFields to gate checks for
5025 // non-serializable non-transient instance fields
5026 boolean serialPersistentFieldsPresent =
5027 c.members()
5028 .getSymbolsByName(names.serialPersistentFields, sym -> sym.kind == VAR)
5029 .iterator()
5030 .hasNext();
5031
5032 // Check declarations of serialization-related methods and
5033 // fields
5034 final Map<String, Symbol> declaredSerialMethodNames = new HashMap<>();
5035 for(Symbol el : c.getEnclosedElements()) {
5036 runUnderLint(el, p, (enclosed, tree) -> {
5037 String name = null;
5038 switch(enclosed.getKind()) {
5039 case FIELD -> {
5040 if (!serialPersistentFieldsPresent) {
5041 var flags = enclosed.flags();
5042 if ( ((flags & TRANSIENT) == 0) &&
5043 ((flags & STATIC) == 0)) {
5044 Type varType = enclosed.asType();
5045 if (!canBeSerialized(varType)) {
5046 // Note per JLS arrays are
5047 // serializable even if the
5048 // component type is not.
5049 log.warning(
5050 TreeInfo.diagnosticPositionFor(enclosed, tree),
5051 LintWarnings.NonSerializableInstanceField);
5052 } else if (varType.hasTag(ARRAY)) {
5053 ArrayType arrayType = (ArrayType)varType;
5054 Type elementType = arrayType.elemtype;
5055 while (elementType.hasTag(ARRAY)) {
5056 arrayType = (ArrayType)elementType;
5057 elementType = arrayType.elemtype;
5058 }
5059 if (!canBeSerialized(elementType)) {
5060 log.warning(
5061 TreeInfo.diagnosticPositionFor(enclosed, tree),
5062 LintWarnings.NonSerializableInstanceFieldArray(elementType));
5063 }
5064 }
5065 }
5066 }
5067
5068 name = enclosed.getSimpleName().toString();
5069 if (serialFieldNames.contains(name)) {
5070 VarSymbol field = (VarSymbol)enclosed;
5071 switch (name) {
5072 case "serialVersionUID" -> checkSerialVersionUID(tree, e, field);
5073 case "serialPersistentFields" -> checkSerialPersistentFields(tree, e, field);
5074 default -> throw new AssertionError();
5075 }
5076 }
5077 }
5078
5079 // Correctly checking the serialization-related
5080 // methods is subtle. For the methods declared to be
5081 // private or directly declared in the class, the
5082 // enclosed elements of the class can be checked in
5083 // turn. However, writeReplace and readResolve can be
5084 // declared in a superclass and inherited. Note that
5085 // the runtime lookup walks the superclass chain
5086 // looking for writeReplace/readResolve via
5087 // Class.getDeclaredMethod. This differs from calling
5088 // Elements.getAllMembers(TypeElement) as the latter
5089 // will also pull in default methods from
5090 // superinterfaces. In other words, the runtime checks
5091 // (which long predate default methods on interfaces)
5092 // do not admit the possibility of inheriting methods
5093 // this way, a difference from general inheritance.
5094
5095 // The current implementation just checks the enclosed
5096 // elements and does not directly check the inherited
5097 // methods. If all the types are being checked this is
5098 // less of a concern; however, there are cases that
5099 // could be missed. In particular, readResolve and
5100 // writeReplace could, in principle, by inherited from
5101 // a non-serializable superclass and thus not checked
5102 // even if compiled with a serializable child class.
5103 case METHOD -> {
5104 var method = (MethodSymbol)enclosed;
5105 name = method.getSimpleName().toString();
5106 if (serialMethodNames.contains(name)) {
5107 if (switch (name) {
5108 case "writeObject" -> hasAppropriateWriteObject(tree, e, method);
5109 case "writeReplace" -> hasAppropriateWriteReplace(tree, method, true);
5110 case "readObject" -> hasAppropriateReadObject(tree, e, method);
5111 case "readObjectNoData" -> hasAppropriateReadObjectNoData(tree, e, method);
5112 case "readResolve" -> hasAppropriateReadResolve(tree, e, method);
5113 default -> throw new AssertionError();
5114 }) {
5115 declaredSerialMethodNames.put(name, el);
5116 }
5117 }
5118 }
5119 }
5120 });
5121 }
5122 if (declaredSerialMethodNames.get("writeReplace") == null &&
5123 (c.isValueClass() || hasAbstractValueSuperClass(c, Set.of(syms.numberType.tsym))) &&
5124 !c.isAbstract() && !c.isRecord() &&
5125 types.unboxedType(c.type) == Type.noType) {
5126 /* if we are dealing with a value class or with a class with a super class that happens to
5127 * be an abstract value class, that is not declaring a proper `writeReplace` method, then we
5128 * need to make sure then that it is inheriting an appropriate one.
5129 */
5130 MethodSymbol ms = null;
5131 Log.DiagnosticHandler discardHandler = log.new DiscardDiagnosticHandler();
5132 try {
5133 ms = rs.resolveInternalMethod(env.tree, env, c.type, names.writeReplace, List.nil(), List.nil());
5134 } catch (FatalError fe) {
5135 // ignore no method was found
5136 } finally {
5137 log.popDiagnosticHandler(discardHandler);
5138 }
5139 if (ms == null || !hasAppropriateWriteReplace(p, ms, false)) {
5140 log.warning(p.pos(),
5141 c.isValueClass() ? LintWarnings.SerializableValueClassWithoutWriteReplace1 :
5142 LintWarnings.SerializableValueClassWithoutWriteReplace2);
5143 }
5144 }
5145 if (c.isValueClass()) {
5146 /* Value classes are Serializable through the use of the serialization proxy pattern.
5147 * The serialization protocol does not support a standard serialized form for value classes.
5148 * The value class delegates to a serialization proxy by supplying an alternate
5149 * record or object to be serialized instead of the value class.
5150 * When the proxy is deserialized it re-constructs the value object and returns the value object.
5151 *
5152 * In particular methods:
5153 * - writeObject
5154 * - readObject and
5155 * - readObjectNoData
5156 * are not invoked for value classes, we need to warn the user about this
5157 */
5158 for (Map.Entry<String, Symbol> entry : declaredSerialMethodNames.entrySet()) {
5159 String key = entry.getKey();
5160 if (key.equals("writeObject") || key.equals("readObject") || key.equals("readObjectNoData")) {
5161 log.warning(TreeInfo.diagnosticPositionFor(entry.getValue(), p), LintWarnings.IneffectualSerialMethodValueClass(key));
5162 }
5163 }
5164 }
5165 return null;
5166 }
5167
5168 boolean canBeSerialized(Type type) {
5169 return type.isPrimitive() || rs.isSerializable(type);
5170 }
5171
5172 private boolean hasAbstractValueSuperClass(Symbol c, Set<Symbol> excluding) {
5173 while (c.getKind() == ElementKind.CLASS) {
5174 Type sup = ((ClassSymbol)c).getSuperclass();
5175 if (!sup.hasTag(CLASS) || sup.isErroneous() ||
5176 sup.tsym == syms.objectType.tsym) {
5177 return false;
5178 }
5179 // if it is a value super class it has to be abstract
5180 if (sup.isValueClass() && !excluding.contains(sup.tsym)) {
5181 return true;
5182 }
5183 c = sup.tsym;
5184 }
5185 return false;
5186 }
5187
5188 /**
5189 * Check that Externalizable class needs a public no-arg
5190 * constructor.
5191 *
5192 * Check that a Serializable class has access to the no-arg
5193 * constructor of its first nonserializable superclass.
5194 */
5195 private void checkCtorAccess(JCClassDecl tree, ClassSymbol c) {
5196 if (isExternalizable(c.type)) {
5197 for(var sym : c.getEnclosedElements()) {
5198 if (sym.isConstructor() &&
5199 ((sym.flags() & PUBLIC) == PUBLIC)) {
5200 if (((MethodSymbol)sym).getParameters().isEmpty()) {
5201 return;
5202 }
5203 }
5204 }
5205 log.warning(tree.pos(),
5206 LintWarnings.ExternalizableMissingPublicNoArgCtor);
5207 } else {
5208 // Approximate access to the no-arg constructor up in
5209 // the superclass chain by checking that the
5210 // constructor is not private. This may not handle
5211 // some cross-package situations correctly.
5212 Type superClass = c.getSuperclass();
5213 // java.lang.Object is *not* Serializable so this loop
5214 // should terminate.
5215 while (rs.isSerializable(superClass) ) {
5216 try {
5217 superClass = (Type)((TypeElement)(((DeclaredType)superClass)).asElement()).getSuperclass();
5218 } catch(ClassCastException cce) {
5219 return ; // Don't try to recover
5220 }
5221 }
5222 // Non-Serializable superclass
5223 try {
5224 ClassSymbol supertype = ((ClassSymbol)(((DeclaredType)superClass).asElement()));
5225 for(var sym : supertype.getEnclosedElements()) {
5226 if (sym.isConstructor()) {
5227 MethodSymbol ctor = (MethodSymbol)sym;
5228 if (ctor.getParameters().isEmpty()) {
5229 if (((ctor.flags() & PRIVATE) == PRIVATE) ||
5230 // Handle nested classes and implicit this$0
5231 (supertype.getNestingKind() == NestingKind.MEMBER &&
5232 ((supertype.flags() & STATIC) == 0)))
5233 log.warning(tree.pos(),
5234 LintWarnings.SerializableMissingAccessNoArgCtor(supertype.getQualifiedName()));
5235 }
5236 }
5237 }
5238 } catch (ClassCastException cce) {
5239 return ; // Don't try to recover
5240 }
5241 return;
5242 }
5243 }
5244
5245 private void checkSerialVersionUID(JCClassDecl tree, Element e, VarSymbol svuid) {
5246 // To be effective, serialVersionUID must be marked static
5247 // and final, but private is recommended. But alas, in
5248 // practice there are many non-private serialVersionUID
5249 // fields.
5250 if ((svuid.flags() & (STATIC | FINAL)) !=
5251 (STATIC | FINAL)) {
5252 log.warning(
5253 TreeInfo.diagnosticPositionFor(svuid, tree),
5254 LintWarnings.ImproperSVUID((Symbol)e));
5255 }
5256
5257 // check svuid has type long
5258 if (!svuid.type.hasTag(LONG)) {
5259 log.warning(
5260 TreeInfo.diagnosticPositionFor(svuid, tree),
5261 LintWarnings.LongSVUID((Symbol)e));
5262 }
5263
5264 if (svuid.getConstValue() == null)
5265 log.warning(
5266 TreeInfo.diagnosticPositionFor(svuid, tree),
5267 LintWarnings.ConstantSVUID((Symbol)e));
5268 }
5269
5270 private void checkSerialPersistentFields(JCClassDecl tree, Element e, VarSymbol spf) {
5271 // To be effective, serialPersisentFields must be private, static, and final.
5272 if ((spf.flags() & (PRIVATE | STATIC | FINAL)) !=
5273 (PRIVATE | STATIC | FINAL)) {
5274 log.warning(
5275 TreeInfo.diagnosticPositionFor(spf, tree),
5276 LintWarnings.ImproperSPF);
5277 }
5278
5279 if (!types.isSameType(spf.type, OSF_TYPE)) {
5280 log.warning(
5281 TreeInfo.diagnosticPositionFor(spf, tree),
5282 LintWarnings.OSFArraySPF);
5283 }
5284
5285 if (isExternalizable((Type)(e.asType()))) {
5286 log.warning(
5287 TreeInfo.diagnosticPositionFor(spf, tree),
5288 LintWarnings.IneffectualSerialFieldExternalizable);
5289 }
5290
5291 // Warn if serialPersistentFields is initialized to a
5292 // literal null.
5293 JCTree spfDecl = TreeInfo.declarationFor(spf, tree);
5294 if (spfDecl != null && spfDecl.getTag() == VARDEF) {
5295 JCVariableDecl variableDef = (JCVariableDecl) spfDecl;
5296 JCExpression initExpr = variableDef.init;
5297 if (initExpr != null && TreeInfo.isNull(initExpr)) {
5298 log.warning(initExpr.pos(),
5299 LintWarnings.SPFNullInit);
5300 }
5301 }
5302 }
5303
5304 private boolean hasAppropriateWriteObject(JCClassDecl tree, Element e, MethodSymbol method) {
5305 // The "synchronized" modifier is seen in the wild on
5306 // readObject and writeObject methods and is generally
5307 // innocuous.
5308
5309 // private void writeObject(ObjectOutputStream stream) throws IOException
5310 return isPrivateNonStaticMethod(tree, method) & // no short-circuit we need to log warnings
5311 isExpectedReturnType(tree, method, syms.voidType, true) &
5312 hasExpectedArg(tree, method, syms.objectOutputStreamType) &
5313 hasExpectedExceptions(tree, method, true, syms.ioExceptionType) &
5314 checkExternalizable(tree, e, method);
5315 }
5316
5317 private boolean hasAppropriateWriteReplace(JCClassDecl tree, MethodSymbol method, boolean warn) {
5318 // ANY-ACCESS-MODIFIER Object writeReplace() throws
5319 // ObjectStreamException
5320
5321 // Excluding abstract, could have a more complicated
5322 // rule based on abstract-ness of the class
5323 return isConcreteInstanceMethod(tree, method, warn) & // no short-circuit we need to log warnings
5324 isExpectedReturnType(tree, method, syms.objectType, warn) &
5325 hasNoArgs(tree, method, warn) &
5326 hasExpectedExceptions(tree, method, warn, syms.objectStreamExceptionType);
5327 }
5328
5329 private boolean hasAppropriateReadObject(JCClassDecl tree, Element e, MethodSymbol method) {
5330 // The "synchronized" modifier is seen in the wild on
5331 // readObject and writeObject methods and is generally
5332 // innocuous.
5333
5334 // private void readObject(ObjectInputStream stream)
5335 // throws IOException, ClassNotFoundException
5336 return isPrivateNonStaticMethod(tree, method) & // no short-circuit we need to log warnings
5337 isExpectedReturnType(tree, method, syms.voidType, true) &
5338 hasExpectedArg(tree, method, syms.objectInputStreamType) &
5339 hasExpectedExceptions(tree, method, true, syms.ioExceptionType, syms.classNotFoundExceptionType) &
5340 checkExternalizable(tree, e, method);
5341 }
5342
5343 private boolean hasAppropriateReadObjectNoData(JCClassDecl tree, Element e, MethodSymbol method) {
5344 // private void readObjectNoData() throws ObjectStreamException
5345 return isPrivateNonStaticMethod(tree, method) & // no short-circuit we need to log warnings
5346 isExpectedReturnType(tree, method, syms.voidType, true) &
5347 hasNoArgs(tree, method, true) &
5348 hasExpectedExceptions(tree, method, true, syms.objectStreamExceptionType) &
5349 checkExternalizable(tree, e, method);
5350 }
5351
5352 private boolean hasAppropriateReadResolve(JCClassDecl tree, Element e, MethodSymbol method) {
5353 // ANY-ACCESS-MODIFIER Object readResolve()
5354 // throws ObjectStreamException
5355
5356 // Excluding abstract, could have a more complicated
5357 // rule based on abstract-ness of the class
5358 return isConcreteInstanceMethod(tree, method, true) & // no short-circuit we need to log warnings
5359 isExpectedReturnType(tree, method, syms.objectType, true) &
5360 hasNoArgs(tree, method, true) &
5361 hasExpectedExceptions(tree, method, true, syms.objectStreamExceptionType);
5362 }
5363
5364 private void checkWriteExternalRecord(JCClassDecl tree, Element e, MethodSymbol method, boolean isExtern) {
5365 //public void writeExternal(ObjectOutput) throws IOException
5366 checkExternMethodRecord(tree, e, method, syms.objectOutputType, isExtern);
5367 }
5368
5369 private void checkReadExternalRecord(JCClassDecl tree, Element e, MethodSymbol method, boolean isExtern) {
5370 // public void readExternal(ObjectInput) throws IOException
5371 checkExternMethodRecord(tree, e, method, syms.objectInputType, isExtern);
5372 }
5373
5374 private void checkExternMethodRecord(JCClassDecl tree, Element e, MethodSymbol method, Type argType,
5375 boolean isExtern) {
5376 if (isExtern && isExternMethod(tree, e, method, argType)) {
5377 log.warning(
5378 TreeInfo.diagnosticPositionFor(method, tree),
5379 LintWarnings.IneffectualExternalizableMethodRecord(method.getSimpleName().toString()));
5380 }
5381 }
5382
5383 boolean isPrivateNonStaticMethod(JCClassDecl tree, MethodSymbol method) {
5384 var flags = method.flags();
5385 boolean result = true;
5386 if ((flags & PRIVATE) == 0) {
5387 log.warning(
5388 TreeInfo.diagnosticPositionFor(method, tree),
5389 LintWarnings.SerialMethodNotPrivate(method.getSimpleName()));
5390 result = false;
5391 }
5392
5393 if ((flags & STATIC) != 0) {
5394 log.warning(
5395 TreeInfo.diagnosticPositionFor(method, tree),
5396 LintWarnings.SerialMethodStatic(method.getSimpleName()));
5397 result = false;
5398 }
5399 return result;
5400 }
5401
5402 /**
5403 * Per section 1.12 "Serialization of Enum Constants" of
5404 * the serialization specification, due to the special
5405 * serialization handling of enums, any writeObject,
5406 * readObject, writeReplace, and readResolve methods are
5407 * ignored as are serialPersistentFields and
5408 * serialVersionUID fields.
5409 */
5410 @Override
5411 public Void visitTypeAsEnum(TypeElement e,
5412 JCClassDecl p) {
5413 boolean isExtern = isExternalizable((Type)e.asType());
5414 for(Element el : e.getEnclosedElements()) {
5415 runUnderLint(el, p, (enclosed, tree) -> {
5416 String name = enclosed.getSimpleName().toString();
5417 switch(enclosed.getKind()) {
5418 case FIELD -> {
5419 var field = (VarSymbol)enclosed;
5420 if (serialFieldNames.contains(name)) {
5421 log.warning(
5422 TreeInfo.diagnosticPositionFor(field, tree),
5423 LintWarnings.IneffectualSerialFieldEnum(name));
5424 }
5425 }
5426
5427 case METHOD -> {
5428 var method = (MethodSymbol)enclosed;
5429 if (serialMethodNames.contains(name)) {
5430 log.warning(
5431 TreeInfo.diagnosticPositionFor(method, tree),
5432 LintWarnings.IneffectualSerialMethodEnum(name));
5433 }
5434
5435 if (isExtern) {
5436 switch(name) {
5437 case "writeExternal" -> checkWriteExternalEnum(tree, e, method);
5438 case "readExternal" -> checkReadExternalEnum(tree, e, method);
5439 }
5440 }
5441 }
5442
5443 // Also perform checks on any class bodies of enum constants, see JLS 8.9.1.
5444 case ENUM_CONSTANT -> {
5445 var field = (VarSymbol)enclosed;
5446 JCVariableDecl decl = (JCVariableDecl) TreeInfo.declarationFor(field, p);
5447 if (decl.init instanceof JCNewClass nc && nc.def != null) {
5448 ClassSymbol enumConstantType = nc.def.sym;
5449 visitTypeAsEnum(enumConstantType, p);
5450 }
5451 }
5452
5453 }});
5454 }
5455 return null;
5456 }
5457
5458 private void checkWriteExternalEnum(JCClassDecl tree, Element e, MethodSymbol method) {
5459 //public void writeExternal(ObjectOutput) throws IOException
5460 checkExternMethodEnum(tree, e, method, syms.objectOutputType);
5461 }
5462
5463 private void checkReadExternalEnum(JCClassDecl tree, Element e, MethodSymbol method) {
5464 // public void readExternal(ObjectInput) throws IOException
5465 checkExternMethodEnum(tree, e, method, syms.objectInputType);
5466 }
5467
5468 private void checkExternMethodEnum(JCClassDecl tree, Element e, MethodSymbol method, Type argType) {
5469 if (isExternMethod(tree, e, method, argType)) {
5470 log.warning(
5471 TreeInfo.diagnosticPositionFor(method, tree),
5472 LintWarnings.IneffectualExternMethodEnum(method.getSimpleName().toString()));
5473 }
5474 }
5475
5476 private boolean isExternMethod(JCClassDecl tree, Element e, MethodSymbol method, Type argType) {
5477 long flags = method.flags();
5478 Type rtype = method.getReturnType();
5479
5480 // Not necessary to check throws clause in this context
5481 return (flags & PUBLIC) != 0 && (flags & STATIC) == 0 &&
5482 types.isSameType(syms.voidType, rtype) &&
5483 hasExactlyOneArgWithType(tree, e, method, argType);
5484 }
5485
5486 /**
5487 * Most serialization-related fields and methods on interfaces
5488 * are ineffectual or problematic.
5489 */
5490 @Override
5491 public Void visitTypeAsInterface(TypeElement e,
5492 JCClassDecl p) {
5493 for(Element el : e.getEnclosedElements()) {
5494 runUnderLint(el, p, (enclosed, tree) -> {
5495 String name = null;
5496 switch(enclosed.getKind()) {
5497 case FIELD -> {
5498 var field = (VarSymbol)enclosed;
5499 name = field.getSimpleName().toString();
5500 switch(name) {
5501 case "serialPersistentFields" -> {
5502 log.warning(
5503 TreeInfo.diagnosticPositionFor(field, tree),
5504 LintWarnings.IneffectualSerialFieldInterface);
5505 }
5506
5507 case "serialVersionUID" -> {
5508 checkSerialVersionUID(tree, e, field);
5509 }
5510 }
5511 }
5512
5513 case METHOD -> {
5514 var method = (MethodSymbol)enclosed;
5515 name = enclosed.getSimpleName().toString();
5516 if (serialMethodNames.contains(name)) {
5517 switch (name) {
5518 case
5519 "readObject",
5520 "readObjectNoData",
5521 "writeObject" -> checkPrivateMethod(tree, e, method);
5522
5523 case
5524 "writeReplace",
5525 "readResolve" -> checkDefaultIneffective(tree, e, method);
5526
5527 default -> throw new AssertionError();
5528 }
5529
5530 }
5531 }}
5532 });
5533 }
5534
5535 return null;
5536 }
5537
5538 private void checkPrivateMethod(JCClassDecl tree,
5539 Element e,
5540 MethodSymbol method) {
5541 if ((method.flags() & PRIVATE) == 0) {
5542 log.warning(
5543 TreeInfo.diagnosticPositionFor(method, tree),
5544 LintWarnings.NonPrivateMethodWeakerAccess);
5545 }
5546 }
5547
5548 private void checkDefaultIneffective(JCClassDecl tree,
5549 Element e,
5550 MethodSymbol method) {
5551 if ((method.flags() & DEFAULT) == DEFAULT) {
5552 log.warning(
5553 TreeInfo.diagnosticPositionFor(method, tree),
5554 LintWarnings.DefaultIneffective);
5555
5556 }
5557 }
5558
5559 @Override
5560 public Void visitTypeAsAnnotationType(TypeElement e,
5561 JCClassDecl p) {
5562 // Per the JLS, annotation types are not serializeable
5563 return null;
5564 }
5565
5566 /**
5567 * From the Java Object Serialization Specification, 1.13
5568 * Serialization of Records:
5569 *
5570 * "The process by which record objects are serialized or
5571 * externalized cannot be customized; any class-specific
5572 * writeObject, readObject, readObjectNoData, writeExternal,
5573 * and readExternal methods defined by record classes are
5574 * ignored during serialization and deserialization. However,
5575 * a substitute object to be serialized or a designate
5576 * replacement may be specified, by the writeReplace and
5577 * readResolve methods, respectively. Any
5578 * serialPersistentFields field declaration is
5579 * ignored. Documenting serializable fields and data for
5580 * record classes is unnecessary, since there is no variation
5581 * in the serial form, other than whether a substitute or
5582 * replacement object is used. The serialVersionUID of a
5583 * record class is 0L unless explicitly declared. The
5584 * requirement for matching serialVersionUID values is waived
5585 * for record classes."
5586 */
5587 @Override
5588 public Void visitTypeAsRecord(TypeElement e,
5589 JCClassDecl p) {
5590 boolean isExtern = isExternalizable((Type)e.asType());
5591 for(Element el : e.getEnclosedElements()) {
5592 runUnderLint(el, p, (enclosed, tree) -> {
5593 String name = enclosed.getSimpleName().toString();
5594 switch(enclosed.getKind()) {
5595 case FIELD -> {
5596 var field = (VarSymbol)enclosed;
5597 switch(name) {
5598 case "serialPersistentFields" -> {
5599 log.warning(
5600 TreeInfo.diagnosticPositionFor(field, tree),
5601 LintWarnings.IneffectualSerialFieldRecord);
5602 }
5603
5604 case "serialVersionUID" -> {
5605 // Could generate additional warning that
5606 // svuid value is not checked to match for
5607 // records.
5608 checkSerialVersionUID(tree, e, field);
5609 }}
5610 }
5611
5612 case METHOD -> {
5613 var method = (MethodSymbol)enclosed;
5614 switch(name) {
5615 case "writeReplace" -> hasAppropriateWriteReplace(tree, method, true);
5616 case "readResolve" -> hasAppropriateReadResolve(tree, e, method);
5617
5618 case "writeExternal" -> checkWriteExternalRecord(tree, e, method, isExtern);
5619 case "readExternal" -> checkReadExternalRecord(tree, e, method, isExtern);
5620
5621 default -> {
5622 if (serialMethodNames.contains(name)) {
5623 log.warning(
5624 TreeInfo.diagnosticPositionFor(method, tree),
5625 LintWarnings.IneffectualSerialMethodRecord(name));
5626 }
5627 }}
5628 }}});
5629 }
5630 return null;
5631 }
5632
5633 boolean isConcreteInstanceMethod(JCClassDecl tree,
5634 MethodSymbol method,
5635 boolean warn) {
5636 if ((method.flags() & (STATIC | ABSTRACT)) != 0) {
5637 if (warn) {
5638 log.warning(
5639 TreeInfo.diagnosticPositionFor(method, tree),
5640 LintWarnings.SerialConcreteInstanceMethod(method.getSimpleName()));
5641 }
5642 return false;
5643 }
5644 return true;
5645 }
5646
5647 private boolean isExpectedReturnType(JCClassDecl tree,
5648 MethodSymbol method,
5649 Type expectedReturnType,
5650 boolean warn) {
5651 // Note: there may be complications checking writeReplace
5652 // and readResolve since they return Object and could, in
5653 // principle, have covariant overrides and any synthetic
5654 // bridge method would not be represented here for
5655 // checking.
5656 Type rtype = method.getReturnType();
5657 if (!types.isSameType(expectedReturnType, rtype)) {
5658 if (warn) {
5659 log.warning(
5660 TreeInfo.diagnosticPositionFor(method, tree),
5661 LintWarnings.SerialMethodUnexpectedReturnType(method.getSimpleName(),
5662 rtype, expectedReturnType));
5663 }
5664 return false;
5665 }
5666 return true;
5667 }
5668
5669 private boolean hasExpectedArg(JCClassDecl tree,
5670 MethodSymbol method,
5671 Type expectedType) {
5672
5673 var parameters= method.getParameters();
5674
5675 if (parameters.size() != 1) {
5676 log.warning(
5677 TreeInfo.diagnosticPositionFor(method, tree),
5678 LintWarnings.SerialMethodOneArg(method.getSimpleName(), parameters.size()));
5679 return false;
5680 }
5681
5682 Type parameterType = parameters.get(0).asType();
5683 if (!types.isSameType(parameterType, expectedType)) {
5684 log.warning(
5685 TreeInfo.diagnosticPositionFor(method, tree),
5686 LintWarnings.SerialMethodParameterType(method.getSimpleName(),
5687 expectedType,
5688 parameterType));
5689 return false;
5690 }
5691 return true;
5692 }
5693
5694 private boolean hasExactlyOneArgWithType(JCClassDecl tree,
5695 Element enclosing,
5696 MethodSymbol method,
5697 Type expectedType) {
5698 var parameters = method.getParameters();
5699 return (parameters.size() == 1) &&
5700 types.isSameType(parameters.get(0).asType(), expectedType);
5701 }
5702
5703
5704 boolean hasNoArgs(JCClassDecl tree, MethodSymbol method, boolean warn) {
5705 var parameters = method.getParameters();
5706 if (!parameters.isEmpty()) {
5707 if (warn) {
5708 log.warning(
5709 TreeInfo.diagnosticPositionFor(parameters.get(0), tree),
5710 LintWarnings.SerialMethodNoArgs(method.getSimpleName()));
5711 }
5712 return false;
5713 }
5714 return true;
5715 }
5716
5717 private boolean checkExternalizable(JCClassDecl tree, Element enclosing, MethodSymbol method) {
5718 // If the enclosing class is externalizable, warn for the method
5719 if (isExternalizable((Type)enclosing.asType())) {
5720 log.warning(
5721 TreeInfo.diagnosticPositionFor(method, tree),
5722 LintWarnings.IneffectualSerialMethodExternalizable(method.getSimpleName()));
5723 return false;
5724 }
5725 return true;
5726 }
5727
5728 private boolean hasExpectedExceptions(JCClassDecl tree,
5729 MethodSymbol method,
5730 boolean warn,
5731 Type... declaredExceptions) {
5732 for (Type thrownType: method.getThrownTypes()) {
5733 // For each exception in the throws clause of the
5734 // method, if not an Error and not a RuntimeException,
5735 // check if the exception is a subtype of a declared
5736 // exception from the throws clause of the
5737 // serialization method in question.
5738 if (types.isSubtype(thrownType, syms.runtimeExceptionType) ||
5739 types.isSubtype(thrownType, syms.errorType) ) {
5740 continue;
5741 } else {
5742 boolean declared = false;
5743 for (Type declaredException : declaredExceptions) {
5744 if (types.isSubtype(thrownType, declaredException)) {
5745 declared = true;
5746 continue;
5747 }
5748 }
5749 if (!declared) {
5750 if (warn) {
5751 log.warning(
5752 TreeInfo.diagnosticPositionFor(method, tree),
5753 LintWarnings.SerialMethodUnexpectedException(method.getSimpleName(),
5754 thrownType));
5755 }
5756 return false;
5757 }
5758 }
5759 }
5760 return true;
5761 }
5762
5763 private <E extends Element> Void runUnderLint(E symbol, JCClassDecl p, BiConsumer<E, JCClassDecl> task) {
5764 Lint prevLint = lint;
5765 try {
5766 lint = lint.augment((Symbol) symbol);
5767
5768 if (lint.isEnabled(LintCategory.SERIAL)) {
5769 task.accept(symbol, p);
5770 }
5771
5772 return null;
5773 } finally {
5774 lint = prevLint;
5775 }
5776 }
5777
5778 }
5779
5780 void checkRequiresIdentity(JCTree tree, Lint lint) {
5781 switch (tree) {
5782 case JCClassDecl classDecl -> {
5783 Type st = types.supertype(classDecl.sym.type);
5784 if (st != null &&
5785 // no need to recheck j.l.Object, shortcut,
5786 st.tsym != syms.objectType.tsym &&
5787 // this one could be null, no explicit extends
5788 classDecl.extending != null) {
5789 checkIfIdentityIsExpected(classDecl.extending.pos(), st, lint);
5790 }
5791 for (JCExpression intrface: classDecl.implementing) {
5792 checkIfIdentityIsExpected(intrface.pos(), intrface.type, lint);
5793 }
5794 for (JCTypeParameter tp : classDecl.typarams) {
5795 checkIfIdentityIsExpected(tp.pos(), tp.type, lint);
5796 }
5797 }
5798 case JCVariableDecl variableDecl -> {
5799 if (variableDecl.vartype != null &&
5800 ((variableDecl.sym.flags_field & RECORD) == 0 ||
5801 (variableDecl.sym.flags_field & ~(Flags.PARAMETER | RECORD | GENERATED_MEMBER)) != 0)) {
5802 /* we don't want to warn twice so if this variable is a compiler generated parameter of
5803 * a canonical record constructor, we don't want to issue a warning as we will warn the
5804 * corresponding compiler generated private record field anyways
5805 */
5806 checkIfIdentityIsExpected(variableDecl.vartype.pos(), variableDecl.vartype.type, lint);
5807 }
5808 }
5809 case JCTypeCast typeCast -> checkIfIdentityIsExpected(typeCast.clazz.pos(), typeCast.clazz.type, lint);
5810 case JCBindingPattern bindingPattern -> {
5811 if (bindingPattern.var.vartype != null) {
5812 checkIfIdentityIsExpected(bindingPattern.var.vartype.pos(), bindingPattern.var.vartype.type, lint);
5813 }
5814 }
5815 case JCMethodDecl methodDecl -> {
5816 for (JCTypeParameter tp : methodDecl.typarams) {
5817 checkIfIdentityIsExpected(tp.pos(), tp.type, lint);
5818 }
5819 if (methodDecl.restype != null && !methodDecl.restype.type.hasTag(VOID)) {
5820 checkIfIdentityIsExpected(methodDecl.restype.pos(), methodDecl.restype.type, lint);
5821 }
5822 }
5823 case JCMemberReference mref -> {
5824 checkIfIdentityIsExpected(mref.expr.pos(), mref.target, lint);
5825 checkIfTypeParamsRequiresIdentity(mref.sym.getMetadata(), mref.typeargs, lint);
5826 }
5827 case JCPolyExpression poly
5828 when (poly instanceof JCNewClass || poly instanceof JCMethodInvocation) -> {
5829 if (poly instanceof JCNewClass newClass) {
5830 checkIfIdentityIsExpected(newClass.clazz.pos(), newClass.clazz.type, lint);
5831 }
5832 List<JCExpression> argExps = poly instanceof JCNewClass ?
5833 ((JCNewClass)poly).args :
5834 ((JCMethodInvocation)poly).args;
5835 Symbol msym = TreeInfo.symbolFor(poly);
5836 if (msym != null) {
5837 if (!argExps.isEmpty() && msym instanceof MethodSymbol ms && ms.params != null) {
5838 VarSymbol lastParam = ms.params.head;
5839 for (VarSymbol param: ms.params) {
5840 if ((param.flags_field & REQUIRES_IDENTITY) != 0 && argExps.head.type.isValueBased()) {
5841 log.warning(argExps.head.pos(), LintWarnings.AttemptToUseValueBasedWhereIdentityExpected);
5842 }
5843 lastParam = param;
5844 argExps = argExps.tail;
5845 }
5846 while (argExps != null && !argExps.isEmpty() && lastParam != null) {
5847 if ((lastParam.flags_field & REQUIRES_IDENTITY) != 0 && argExps.head.type.isValueBased()) {
5848 log.warning(argExps.head.pos(), LintWarnings.AttemptToUseValueBasedWhereIdentityExpected);
5849 }
5850 argExps = argExps.tail;
5851 }
5852 }
5853 checkIfTypeParamsRequiresIdentity(
5854 msym.getMetadata(),
5855 poly instanceof JCNewClass ?
5856 ((JCNewClass)poly).typeargs :
5857 ((JCMethodInvocation)poly).typeargs,
5858 lint);
5859 }
5860 }
5861 default -> throw new AssertionError("unexpected tree " + tree);
5862 }
5863 }
5864
5865 /** Check if a type required an identity class
5866 */
5867 private boolean checkIfIdentityIsExpected(DiagnosticPosition pos, Type t, Lint lint) {
5868 if (t != null &&
5869 lint != null &&
5870 lint.isEnabled(LintCategory.IDENTITY)) {
5871 RequiresIdentityVisitor requiresIdentityVisitor = new RequiresIdentityVisitor();
5872 // we need to avoid recursion due to self referencing type vars or captures, this is why we need a set
5873 requiresIdentityVisitor.visit(t, new HashSet<>());
5874 if (requiresIdentityVisitor.requiresWarning) {
5875 log.warning(pos, LintWarnings.AttemptToUseValueBasedWhereIdentityExpected);
5876 return true;
5877 }
5878 }
5879 return false;
5880 }
5881
5882 // where
5883 private class RequiresIdentityVisitor extends Types.SimpleVisitor<Void, Set<Type>> {
5884 boolean requiresWarning = false;
5885
5886 @Override
5887 public Void visitType(Type t, Set<Type> seen) {
5888 return null;
5889 }
5890
5891 @Override
5892 public Void visitWildcardType(WildcardType t, Set<Type> seen) {
5893 return visit(t.type, seen);
5894 }
5895
5896 @Override
5897 public Void visitTypeVar(TypeVar t, Set<Type> seen) {
5898 if (seen.add(t)) {
5899 visit(t.getUpperBound(), seen);
5900 }
5901 return null;
5902 }
5903
5904 @Override
5905 public Void visitCapturedType(CapturedType t, Set<Type> seen) {
5906 if (seen.add(t)) {
5907 visit(t.getUpperBound(), seen);
5908 visit(t.getLowerBound(), seen);
5909 }
5910 return null;
5911 }
5912
5913 @Override
5914 public Void visitArrayType(ArrayType t, Set<Type> seen) {
5915 return visit(t.elemtype, seen);
5916 }
5917
5918 @Override
5919 public Void visitClassType(ClassType t, Set<Type> seen) {
5920 if (t != null && t.tsym != null) {
5921 SymbolMetadata sm = t.tsym.getMetadata();
5922 if (sm != null && !t.getTypeArguments().isEmpty()) {
5923 if (sm.getTypeAttributes().stream()
5924 .filter(ta -> isRequiresIdentityAnnotation(ta.type.tsym) &&
5925 t.getTypeArguments().get(ta.position.parameter_index) != null &&
5926 t.getTypeArguments().get(ta.position.parameter_index).isValueBased()).findAny().isPresent()) {
5927 requiresWarning = true;
5928 return null;
5929 }
5930 }
5931 }
5932 visit(t.getEnclosingType(), seen);
5933 for (Type targ : t.getTypeArguments()) {
5934 visit(targ, seen);
5935 }
5936 return null;
5937 }
5938 } // RequiresIdentityVisitor
5939
5940 private void checkIfTypeParamsRequiresIdentity(SymbolMetadata sm,
5941 List<JCExpression> typeParamTrees,
5942 Lint lint) {
5943 if (typeParamTrees != null && !typeParamTrees.isEmpty()) {
5944 for (JCExpression targ : typeParamTrees) {
5945 checkIfIdentityIsExpected(targ.pos(), targ.type, lint);
5946 }
5947 if (sm != null)
5948 sm.getTypeAttributes().stream()
5949 .filter(ta -> isRequiresIdentityAnnotation(ta.type.tsym) &&
5950 typeParamTrees.get(ta.position.parameter_index).type != null &&
5951 typeParamTrees.get(ta.position.parameter_index).type.isValueBased())
5952 .forEach(ta -> log.warning(typeParamTrees.get(ta.position.parameter_index).pos(),
5953 CompilerProperties.LintWarnings.AttemptToUseValueBasedWhereIdentityExpected));
5954 }
5955 }
5956
5957 private boolean isRequiresIdentityAnnotation(TypeSymbol annoType) {
5958 return annoType == syms.requiresIdentityType.tsym ||
5959 annoType.flatName() == syms.requiresIdentityInternalType.tsym.flatName();
5960 }
5961 }
--- EOF ---