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