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