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