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)).baseType();
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 if (shouldCheckPreview(m, other, origin)) {
1832 checkPreview(tree.pos(), m, other);
1833 }
1834
1835 Type mt = types.memberType(origin.type, m);
1836 Type ot = types.memberType(origin.type, other);
1837 // Error if overriding result type is different
1838 // (or, in the case of generics mode, not a subtype) of
1839 // overridden result type. We have to rename any type parameters
1840 // before comparing types.
1841 List<Type> mtvars = mt.getTypeArguments();
1842 List<Type> otvars = ot.getTypeArguments();
1843 Type mtres = mt.getReturnType();
1844 Type otres = types.subst(ot.getReturnType(), otvars, mtvars);
1845
1846 overrideWarner.clear();
1847 boolean resultTypesOK =
1848 types.returnTypeSubstitutable(mt, ot, otres, overrideWarner);
1849 if (!resultTypesOK) {
1850 if ((m.flags() & STATIC) != 0 && (other.flags() & STATIC) != 0) {
1851 log.error(TreeInfo.diagnosticPositionFor(m, tree),
1852 Errors.OverrideIncompatibleRet(Fragments.CantHide(m, m.location(), other,
1853 other.location()), mtres, otres));
1854 m.flags_field |= BAD_OVERRIDE;
1855 } else {
1856 log.error(TreeInfo.diagnosticPositionFor(m, tree),
1857 Errors.OverrideIncompatibleRet(cannotOverride(m, other), mtres, otres));
1858 m.flags_field |= BAD_OVERRIDE;
1859 }
1860 return;
1861 } else if (overrideWarner.hasNonSilentLint(LintCategory.UNCHECKED)) {
1862 warnUnchecked(TreeInfo.diagnosticPositionFor(m, tree),
1863 Warnings.OverrideUncheckedRet(uncheckedOverrides(m, other), mtres, otres));
1864 }
1865
1866 // Error if overriding method throws an exception not reported
1867 // by overridden method.
1868 List<Type> otthrown = types.subst(ot.getThrownTypes(), otvars, mtvars);
1869 List<Type> unhandledErased = unhandled(mt.getThrownTypes(), types.erasure(otthrown));
1870 List<Type> unhandledUnerased = unhandled(mt.getThrownTypes(), otthrown);
1871 if (unhandledErased.nonEmpty()) {
1872 log.error(TreeInfo.diagnosticPositionFor(m, tree),
1873 Errors.OverrideMethDoesntThrow(cannotOverride(m, other), unhandledUnerased.head));
1874 m.flags_field |= BAD_OVERRIDE;
1875 return;
1876 }
1877 else if (unhandledUnerased.nonEmpty()) {
1878 warnUnchecked(TreeInfo.diagnosticPositionFor(m, tree),
1879 Warnings.OverrideUncheckedThrown(cannotOverride(m, other), unhandledUnerased.head));
1880 return;
1881 }
1882
1883 // Optional warning if varargs don't agree
1884 if ((((m.flags() ^ other.flags()) & Flags.VARARGS) != 0)
1885 && lint.isEnabled(LintCategory.OVERRIDES)) {
1886 log.warning(TreeInfo.diagnosticPositionFor(m, tree),
1887 ((m.flags() & Flags.VARARGS) != 0)
1888 ? Warnings.OverrideVarargsMissing(varargsOverrides(m, other))
1889 : Warnings.OverrideVarargsExtra(varargsOverrides(m, other)));
1890 }
1891
1892 // Warn if instance method overrides bridge method (compiler spec ??)
1893 if ((other.flags() & BRIDGE) != 0) {
1894 log.warning(TreeInfo.diagnosticPositionFor(m, tree),
1895 Warnings.OverrideBridge(uncheckedOverrides(m, other)));
1896 }
1897
1898 // Warn if a deprecated method overridden by a non-deprecated one.
1899 if (!isDeprecatedOverrideIgnorable(other, origin)) {
1900 Lint prevLint = setLint(lint.augment(m));
1901 try {
1902 checkDeprecated(() -> TreeInfo.diagnosticPositionFor(m, tree), m, other);
1903 } finally {
1904 setLint(prevLint);
1905 }
1906 }
1907 }
1908 // where
1909 private boolean shouldCheckPreview(MethodSymbol m, MethodSymbol other, ClassSymbol origin) {
1910 if (m.owner != origin ||
1911 //performance - only do the expensive checks when the overridden method is a Preview API:
1912 (other.flags() & PREVIEW_API) == 0) {
1913 return false;
1914 }
1915
1916 for (Symbol s : types.membersClosure(origin.type, false).getSymbolsByName(m.name)) {
1917 if (m != s && m.overrides(s, origin, types, false)) {
1918 //only produce preview warnings or errors if "m" immediatelly overrides "other"
1919 //without intermediate overriding methods:
1920 return s == other;
1921 }
1922 }
1923
1924 return false;
1925 }
1926 private boolean isDeprecatedOverrideIgnorable(MethodSymbol m, ClassSymbol origin) {
1927 // If the method, m, is defined in an interface, then ignore the issue if the method
1928 // is only inherited via a supertype and also implemented in the supertype,
1929 // because in that case, we will rediscover the issue when examining the method
1930 // in the supertype.
1931 // If the method, m, is not defined in an interface, then the only time we need to
1932 // address the issue is when the method is the supertype implementation: any other
1933 // case, we will have dealt with when examining the supertype classes
1934 ClassSymbol mc = m.enclClass();
1935 Type st = types.supertype(origin.type);
1936 if (!st.hasTag(CLASS))
1937 return true;
1938 MethodSymbol stimpl = m.implementation((ClassSymbol)st.tsym, types, false);
1939
1940 if (mc != null && ((mc.flags() & INTERFACE) != 0)) {
1941 List<Type> intfs = types.interfaces(origin.type);
1942 return (intfs.contains(mc.type) ? false : (stimpl != null));
1943 }
1944 else
1945 return (stimpl != m);
1946 }
1947
1948
1949 // used to check if there were any unchecked conversions
1950 Warner overrideWarner = new Warner();
1951
1952 /** Check that a class does not inherit two concrete methods
1953 * with the same signature.
1954 * @param pos Position to be used for error reporting.
1955 * @param site The class type to be checked.
1956 */
1957 public void checkCompatibleConcretes(DiagnosticPosition pos, Type site) {
1958 Type sup = types.supertype(site);
1959 if (!sup.hasTag(CLASS)) return;
1960
1961 for (Type t1 = sup;
1962 t1.hasTag(CLASS) && t1.tsym.type.isParameterized();
1963 t1 = types.supertype(t1)) {
1964 for (Symbol s1 : t1.tsym.members().getSymbols(NON_RECURSIVE)) {
1965 if (s1.kind != MTH ||
1966 (s1.flags() & (STATIC|SYNTHETIC|BRIDGE)) != 0 ||
1967 !s1.isInheritedIn(site.tsym, types) ||
1968 ((MethodSymbol)s1).implementation(site.tsym,
1969 types,
1970 true) != s1)
1971 continue;
1972 Type st1 = types.memberType(t1, s1);
1973 int s1ArgsLength = st1.getParameterTypes().length();
1974 if (st1 == s1.type) continue;
1975
1976 for (Type t2 = sup;
1977 t2.hasTag(CLASS);
1978 t2 = types.supertype(t2)) {
1979 for (Symbol s2 : t2.tsym.members().getSymbolsByName(s1.name)) {
1980 if (s2 == s1 ||
1981 s2.kind != MTH ||
1982 (s2.flags() & (STATIC|SYNTHETIC|BRIDGE)) != 0 ||
1983 s2.type.getParameterTypes().length() != s1ArgsLength ||
1984 !s2.isInheritedIn(site.tsym, types) ||
1985 ((MethodSymbol)s2).implementation(site.tsym,
1986 types,
1987 true) != s2)
1988 continue;
1989 Type st2 = types.memberType(t2, s2);
1990 if (types.overrideEquivalent(st1, st2))
1991 log.error(pos,
1992 Errors.ConcreteInheritanceConflict(s1, t1, s2, t2, sup));
1993 }
1994 }
1995 }
1996 }
1997 }
1998
1999 /** Check that classes (or interfaces) do not each define an abstract
2000 * method with same name and arguments but incompatible return types.
2001 * @param pos Position to be used for error reporting.
2002 * @param t1 The first argument type.
2003 * @param t2 The second argument type.
2004 */
2005 public boolean checkCompatibleAbstracts(DiagnosticPosition pos,
2006 Type t1,
2007 Type t2,
2008 Type site) {
2009 if ((site.tsym.flags() & COMPOUND) != 0) {
2010 // special case for intersections: need to eliminate wildcards in supertypes
2011 t1 = types.capture(t1);
2012 t2 = types.capture(t2);
2013 }
2014 return firstIncompatibility(pos, t1, t2, site) == null;
2015 }
2016
2017 /** Return the first method which is defined with same args
2018 * but different return types in two given interfaces, or null if none
2019 * exists.
2020 * @param t1 The first type.
2021 * @param t2 The second type.
2022 * @param site The most derived type.
2023 * @return symbol from t2 that conflicts with one in t1.
2024 */
2025 private Symbol firstIncompatibility(DiagnosticPosition pos, Type t1, Type t2, Type site) {
2026 Map<TypeSymbol,Type> interfaces1 = new HashMap<>();
2027 closure(t1, interfaces1);
2028 Map<TypeSymbol,Type> interfaces2;
2029 if (t1 == t2)
2030 interfaces2 = interfaces1;
2031 else
2032 closure(t2, interfaces1, interfaces2 = new HashMap<>());
2033
2034 for (Type t3 : interfaces1.values()) {
2035 for (Type t4 : interfaces2.values()) {
2036 Symbol s = firstDirectIncompatibility(pos, t3, t4, site);
2037 if (s != null) return s;
2038 }
2039 }
2040 return null;
2041 }
2042
2043 /** Compute all the supertypes of t, indexed by type symbol. */
2044 private void closure(Type t, Map<TypeSymbol,Type> typeMap) {
2045 if (!t.hasTag(CLASS)) return;
2046 if (typeMap.put(t.tsym, t) == null) {
2047 closure(types.supertype(t), typeMap);
2048 for (Type i : types.interfaces(t))
2049 closure(i, typeMap);
2050 }
2051 }
2052
2053 /** Compute all the supertypes of t, indexed by type symbol (except those in typesSkip). */
2054 private void closure(Type t, Map<TypeSymbol,Type> typesSkip, Map<TypeSymbol,Type> typeMap) {
2055 if (!t.hasTag(CLASS)) return;
2056 if (typesSkip.get(t.tsym) != null) return;
2057 if (typeMap.put(t.tsym, t) == null) {
2058 closure(types.supertype(t), typesSkip, typeMap);
2059 for (Type i : types.interfaces(t))
2060 closure(i, typesSkip, typeMap);
2061 }
2062 }
2063
2064 /** Return the first method in t2 that conflicts with a method from t1. */
2065 private Symbol firstDirectIncompatibility(DiagnosticPosition pos, Type t1, Type t2, Type site) {
2066 for (Symbol s1 : t1.tsym.members().getSymbols(NON_RECURSIVE)) {
2067 Type st1 = null;
2068 if (s1.kind != MTH || !s1.isInheritedIn(site.tsym, types) ||
2069 (s1.flags() & SYNTHETIC) != 0) continue;
2070 Symbol impl = ((MethodSymbol)s1).implementation(site.tsym, types, false);
2071 if (impl != null && (impl.flags() & ABSTRACT) == 0) continue;
2072 for (Symbol s2 : t2.tsym.members().getSymbolsByName(s1.name)) {
2073 if (s1 == s2) continue;
2074 if (s2.kind != MTH || !s2.isInheritedIn(site.tsym, types) ||
2075 (s2.flags() & SYNTHETIC) != 0) continue;
2076 if (st1 == null) st1 = types.memberType(t1, s1);
2077 Type st2 = types.memberType(t2, s2);
2078 if (types.overrideEquivalent(st1, st2)) {
2079 List<Type> tvars1 = st1.getTypeArguments();
2080 List<Type> tvars2 = st2.getTypeArguments();
2081 Type rt1 = st1.getReturnType();
2082 Type rt2 = types.subst(st2.getReturnType(), tvars2, tvars1);
2083 boolean compat =
2084 types.isSameType(rt1, rt2) ||
2085 !rt1.isPrimitiveOrVoid() &&
2086 !rt2.isPrimitiveOrVoid() &&
2087 (types.covariantReturnType(rt1, rt2, types.noWarnings) ||
2088 types.covariantReturnType(rt2, rt1, types.noWarnings)) ||
2089 checkCommonOverriderIn(s1,s2,site);
2090 if (!compat) {
2091 log.error(pos, Errors.TypesIncompatible(t1, t2,
2092 Fragments.IncompatibleDiffRet(s2.name, types.memberType(t2, s2).getParameterTypes())));
2093 return s2;
2094 }
2095 } else if (checkNameClash((ClassSymbol)site.tsym, s1, s2) &&
2096 !checkCommonOverriderIn(s1, s2, site)) {
2097 log.error(pos, Errors.NameClashSameErasureNoOverride(
2098 s1.name, types.memberType(site, s1).asMethodType().getParameterTypes(), s1.location(),
2099 s2.name, types.memberType(site, s2).asMethodType().getParameterTypes(), s2.location()));
2100 return s2;
2101 }
2102 }
2103 }
2104 return null;
2105 }
2106 //WHERE
2107 boolean checkCommonOverriderIn(Symbol s1, Symbol s2, Type site) {
2108 Map<TypeSymbol,Type> supertypes = new HashMap<>();
2109 Type st1 = types.memberType(site, s1);
2110 Type st2 = types.memberType(site, s2);
2111 closure(site, supertypes);
2112 for (Type t : supertypes.values()) {
2113 for (Symbol s3 : t.tsym.members().getSymbolsByName(s1.name)) {
2114 if (s3 == s1 || s3 == s2 || s3.kind != MTH || (s3.flags() & (BRIDGE|SYNTHETIC)) != 0) continue;
2115 Type st3 = types.memberType(site,s3);
2116 if (types.overrideEquivalent(st3, st1) &&
2117 types.overrideEquivalent(st3, st2) &&
2118 types.returnTypeSubstitutable(st3, st1) &&
2119 types.returnTypeSubstitutable(st3, st2)) {
2120 return true;
2121 }
2122 }
2123 }
2124 return false;
2125 }
2126
2127 /** Check that a given method conforms with any method it overrides.
2128 * @param tree The tree from which positions are extracted
2129 * for errors.
2130 * @param m The overriding method.
2131 */
2132 void checkOverride(Env<AttrContext> env, JCMethodDecl tree, MethodSymbol m) {
2133 ClassSymbol origin = (ClassSymbol)m.owner;
2134 if ((origin.flags() & ENUM) != 0 && names.finalize.equals(m.name)) {
2135 if (m.overrides(syms.enumFinalFinalize, origin, types, false)) {
2136 log.error(tree.pos(), Errors.EnumNoFinalize);
2137 return;
2138 }
2139 }
2140 if (allowRecords && origin.isRecord()) {
2141 // let's find out if this is a user defined accessor in which case the @Override annotation is acceptable
2142 Optional<? extends RecordComponent> recordComponent = origin.getRecordComponents().stream()
2143 .filter(rc -> rc.accessor == tree.sym && (rc.accessor.flags_field & GENERATED_MEMBER) == 0).findFirst();
2144 if (recordComponent.isPresent()) {
2145 return;
2146 }
2147 }
2148
2149 for (Type t = origin.type; t.hasTag(CLASS);
2150 t = types.supertype(t)) {
2151 if (t != origin.type) {
2152 checkOverride(tree, t, origin, m);
2153 }
2154 for (Type t2 : types.interfaces(t)) {
2155 checkOverride(tree, t2, origin, m);
2156 }
2157 }
2158
2159 final boolean explicitOverride = m.attribute(syms.overrideType.tsym) != null;
2160 // Check if this method must override a super method due to being annotated with @Override
2161 // or by virtue of being a member of a diamond inferred anonymous class. Latter case is to
2162 // be treated "as if as they were annotated" with @Override.
2163 boolean mustOverride = explicitOverride ||
2164 (env.info.isAnonymousDiamond && !m.isConstructor() && !m.isPrivate());
2165 if (mustOverride && !isOverrider(m)) {
2166 DiagnosticPosition pos = tree.pos();
2167 for (JCAnnotation a : tree.getModifiers().annotations) {
2168 if (a.annotationType.type.tsym == syms.overrideType.tsym) {
2169 pos = a.pos();
2170 break;
2171 }
2172 }
2173 log.error(pos,
2174 explicitOverride ? (m.isStatic() ? Errors.StaticMethodsCannotBeAnnotatedWithOverride : Errors.MethodDoesNotOverrideSuperclass) :
2175 Errors.AnonymousDiamondMethodDoesNotOverrideSuperclass(Fragments.DiamondAnonymousMethodsImplicitlyOverride));
2176 }
2177 }
2178
2179 void checkOverride(JCTree tree, Type site, ClassSymbol origin, MethodSymbol m) {
2180 TypeSymbol c = site.tsym;
2181 for (Symbol sym : c.members().getSymbolsByName(m.name)) {
2182 if (m.overrides(sym, origin, types, false)) {
2183 if ((sym.flags() & ABSTRACT) == 0) {
2184 checkOverride(tree, m, (MethodSymbol)sym, origin);
2185 }
2186 }
2187 }
2188 }
2189
2190 private Predicate<Symbol> equalsHasCodeFilter = s -> MethodSymbol.implementation_filter.test(s) &&
2191 (s.flags() & BAD_OVERRIDE) == 0;
2192
2193 public void checkClassOverrideEqualsAndHashIfNeeded(DiagnosticPosition pos,
2194 ClassSymbol someClass) {
2195 /* At present, annotations cannot possibly have a method that is override
2196 * equivalent with Object.equals(Object) but in any case the condition is
2197 * fine for completeness.
2198 */
2199 if (someClass == (ClassSymbol)syms.objectType.tsym ||
2200 someClass.isInterface() || someClass.isEnum() ||
2201 (someClass.flags() & ANNOTATION) != 0 ||
2202 (someClass.flags() & ABSTRACT) != 0) return;
2203 //anonymous inner classes implementing interfaces need especial treatment
2204 if (someClass.isAnonymous()) {
2205 List<Type> interfaces = types.interfaces(someClass.type);
2206 if (interfaces != null && !interfaces.isEmpty() &&
2207 interfaces.head.tsym == syms.comparatorType.tsym) return;
2208 }
2209 checkClassOverrideEqualsAndHash(pos, someClass);
2210 }
2211
2212 private void checkClassOverrideEqualsAndHash(DiagnosticPosition pos,
2213 ClassSymbol someClass) {
2214 if (lint.isEnabled(LintCategory.OVERRIDES)) {
2215 MethodSymbol equalsAtObject = (MethodSymbol)syms.objectType
2216 .tsym.members().findFirst(names.equals);
2217 MethodSymbol hashCodeAtObject = (MethodSymbol)syms.objectType
2218 .tsym.members().findFirst(names.hashCode);
2219 MethodSymbol equalsImpl = types.implementation(equalsAtObject,
2220 someClass, false, equalsHasCodeFilter);
2221 boolean overridesEquals = equalsImpl != null &&
2222 equalsImpl.owner == someClass;
2223 boolean overridesHashCode = types.implementation(hashCodeAtObject,
2224 someClass, false, equalsHasCodeFilter) != hashCodeAtObject;
2225
2226 if (overridesEquals && !overridesHashCode) {
2227 log.warning(LintCategory.OVERRIDES, pos,
2228 Warnings.OverrideEqualsButNotHashcode(someClass));
2229 }
2230 }
2231 }
2232
2233 public void checkModuleName (JCModuleDecl tree) {
2234 Name moduleName = tree.sym.name;
2235 Assert.checkNonNull(moduleName);
2236 if (lint.isEnabled(LintCategory.MODULE)) {
2237 JCExpression qualId = tree.qualId;
2238 while (qualId != null) {
2239 Name componentName;
2240 DiagnosticPosition pos;
2241 switch (qualId.getTag()) {
2242 case SELECT:
2243 JCFieldAccess selectNode = ((JCFieldAccess) qualId);
2244 componentName = selectNode.name;
2245 pos = selectNode.pos();
2246 qualId = selectNode.selected;
2247 break;
2248 case IDENT:
2249 componentName = ((JCIdent) qualId).name;
2250 pos = qualId.pos();
2251 qualId = null;
2252 break;
2253 default:
2254 throw new AssertionError("Unexpected qualified identifier: " + qualId.toString());
2255 }
2256 if (componentName != null) {
2257 String moduleNameComponentString = componentName.toString();
2258 int nameLength = moduleNameComponentString.length();
2259 if (nameLength > 0 && Character.isDigit(moduleNameComponentString.charAt(nameLength - 1))) {
2260 log.warning(Lint.LintCategory.MODULE, pos, Warnings.PoorChoiceForModuleName(componentName));
2261 }
2262 }
2263 }
2264 }
2265 }
2266
2267 private boolean checkNameClash(ClassSymbol origin, Symbol s1, Symbol s2) {
2268 ClashFilter cf = new ClashFilter(origin.type);
2269 return (cf.test(s1) &&
2270 cf.test(s2) &&
2271 types.hasSameArgs(s1.erasure(types), s2.erasure(types)));
2272 }
2273
2274
2275 /** Check that all abstract members of given class have definitions.
2276 * @param pos Position to be used for error reporting.
2277 * @param c The class.
2278 */
2279 void checkAllDefined(DiagnosticPosition pos, ClassSymbol c) {
2280 MethodSymbol undef = types.firstUnimplementedAbstract(c);
2281 if (undef != null) {
2282 MethodSymbol undef1 =
2283 new MethodSymbol(undef.flags(), undef.name,
2284 types.memberType(c.type, undef), undef.owner);
2285 log.error(pos,
2286 Errors.DoesNotOverrideAbstract(c, undef1, undef1.location()));
2287 }
2288 }
2289
2290 void checkNonCyclicDecl(JCClassDecl tree) {
2291 CycleChecker cc = new CycleChecker();
2292 cc.scan(tree);
2293 if (!cc.errorFound && !cc.partialCheck) {
2294 tree.sym.flags_field |= ACYCLIC;
2295 }
2296 }
2297
2298 class CycleChecker extends TreeScanner {
2299
2300 Set<Symbol> seenClasses = new HashSet<>();
2301 boolean errorFound = false;
2302 boolean partialCheck = false;
2303
2304 private void checkSymbol(DiagnosticPosition pos, Symbol sym) {
2305 if (sym != null && sym.kind == TYP) {
2306 Env<AttrContext> classEnv = enter.getEnv((TypeSymbol)sym);
2307 if (classEnv != null) {
2308 DiagnosticSource prevSource = log.currentSource();
2309 try {
2310 log.useSource(classEnv.toplevel.sourcefile);
2311 scan(classEnv.tree);
2312 }
2313 finally {
2314 log.useSource(prevSource.getFile());
2315 }
2316 } else if (sym.kind == TYP) {
2317 checkClass(pos, sym, List.nil());
2318 }
2319 } else if (sym == null || sym.kind != PCK) {
2320 //not completed yet
2321 partialCheck = true;
2322 }
2323 }
2324
2325 @Override
2326 public void visitSelect(JCFieldAccess tree) {
2327 super.visitSelect(tree);
2328 checkSymbol(tree.pos(), tree.sym);
2329 }
2330
2331 @Override
2332 public void visitIdent(JCIdent tree) {
2333 checkSymbol(tree.pos(), tree.sym);
2334 }
2335
2336 @Override
2337 public void visitTypeApply(JCTypeApply tree) {
2338 scan(tree.clazz);
2339 }
2340
2341 @Override
2342 public void visitTypeArray(JCArrayTypeTree tree) {
2343 scan(tree.elemtype);
2344 }
2345
2346 @Override
2347 public void visitClassDef(JCClassDecl tree) {
2348 List<JCTree> supertypes = List.nil();
2349 if (tree.getExtendsClause() != null) {
2350 supertypes = supertypes.prepend(tree.getExtendsClause());
2351 }
2352 if (tree.getImplementsClause() != null) {
2353 for (JCTree intf : tree.getImplementsClause()) {
2354 supertypes = supertypes.prepend(intf);
2355 }
2356 }
2357 checkClass(tree.pos(), tree.sym, supertypes);
2358 }
2359
2360 void checkClass(DiagnosticPosition pos, Symbol c, List<JCTree> supertypes) {
2361 if ((c.flags_field & ACYCLIC) != 0)
2362 return;
2363 if (seenClasses.contains(c)) {
2364 errorFound = true;
2365 noteCyclic(pos, (ClassSymbol)c);
2366 } else if (!c.type.isErroneous()) {
2367 try {
2368 seenClasses.add(c);
2369 if (c.type.hasTag(CLASS)) {
2370 if (supertypes.nonEmpty()) {
2371 scan(supertypes);
2372 }
2373 else {
2374 ClassType ct = (ClassType)c.type;
2375 if (ct.supertype_field == null ||
2376 ct.interfaces_field == null) {
2377 //not completed yet
2378 partialCheck = true;
2379 return;
2380 }
2381 checkSymbol(pos, ct.supertype_field.tsym);
2382 for (Type intf : ct.interfaces_field) {
2383 checkSymbol(pos, intf.tsym);
2384 }
2385 }
2386 if (c.owner.kind == TYP) {
2387 checkSymbol(pos, c.owner);
2388 }
2389 }
2390 } finally {
2391 seenClasses.remove(c);
2392 }
2393 }
2394 }
2395 }
2396
2397 /** Check for cyclic references. Issue an error if the
2398 * symbol of the type referred to has a LOCKED flag set.
2399 *
2400 * @param pos Position to be used for error reporting.
2401 * @param t The type referred to.
2402 */
2403 void checkNonCyclic(DiagnosticPosition pos, Type t) {
2404 checkNonCyclicInternal(pos, t);
2405 }
2406
2407
2408 void checkNonCyclic(DiagnosticPosition pos, TypeVar t) {
2409 checkNonCyclic1(pos, t, List.nil());
2410 }
2411
2412 private void checkNonCyclic1(DiagnosticPosition pos, Type t, List<TypeVar> seen) {
2413 final TypeVar tv;
2414 if (t.hasTag(TYPEVAR) && (t.tsym.flags() & UNATTRIBUTED) != 0)
2415 return;
2416 if (seen.contains(t)) {
2417 tv = (TypeVar)t;
2418 tv.setUpperBound(types.createErrorType(t));
2419 log.error(pos, Errors.CyclicInheritance(t));
2420 } else if (t.hasTag(TYPEVAR)) {
2421 tv = (TypeVar)t;
2422 seen = seen.prepend(tv);
2423 for (Type b : types.getBounds(tv))
2424 checkNonCyclic1(pos, b, seen);
2425 }
2426 }
2427
2428 /** Check for cyclic references. Issue an error if the
2429 * symbol of the type referred to has a LOCKED flag set.
2430 *
2431 * @param pos Position to be used for error reporting.
2432 * @param t The type referred to.
2433 * @returns True if the check completed on all attributed classes
2434 */
2435 private boolean checkNonCyclicInternal(DiagnosticPosition pos, Type t) {
2436 boolean complete = true; // was the check complete?
2437 //- System.err.println("checkNonCyclicInternal("+t+");");//DEBUG
2438 Symbol c = t.tsym;
2439 if ((c.flags_field & ACYCLIC) != 0) return true;
2440
2441 if ((c.flags_field & LOCKED) != 0) {
2442 noteCyclic(pos, (ClassSymbol)c);
2443 } else if (!c.type.isErroneous()) {
2444 try {
2445 c.flags_field |= LOCKED;
2446 if (c.type.hasTag(CLASS)) {
2447 ClassType clazz = (ClassType)c.type;
2448 if (clazz.interfaces_field != null)
2449 for (List<Type> l=clazz.interfaces_field; l.nonEmpty(); l=l.tail)
2450 complete &= checkNonCyclicInternal(pos, l.head);
2451 if (clazz.supertype_field != null) {
2452 Type st = clazz.supertype_field;
2453 if (st != null && st.hasTag(CLASS))
2454 complete &= checkNonCyclicInternal(pos, st);
2455 }
2456 if (c.owner.kind == TYP)
2457 complete &= checkNonCyclicInternal(pos, c.owner.type);
2458 }
2459 } finally {
2460 c.flags_field &= ~LOCKED;
2461 }
2462 }
2463 if (complete)
2464 complete = ((c.flags_field & UNATTRIBUTED) == 0) && c.isCompleted();
2465 if (complete) c.flags_field |= ACYCLIC;
2466 return complete;
2467 }
2468
2469 /** Note that we found an inheritance cycle. */
2470 private void noteCyclic(DiagnosticPosition pos, ClassSymbol c) {
2471 log.error(pos, Errors.CyclicInheritance(c));
2472 for (List<Type> l=types.interfaces(c.type); l.nonEmpty(); l=l.tail)
2473 l.head = types.createErrorType((ClassSymbol)l.head.tsym, Type.noType);
2474 Type st = types.supertype(c.type);
2475 if (st.hasTag(CLASS))
2476 ((ClassType)c.type).supertype_field = types.createErrorType((ClassSymbol)st.tsym, Type.noType);
2477 c.type = types.createErrorType(c, c.type);
2478 c.flags_field |= ACYCLIC;
2479 }
2480
2481 /** Check that all methods which implement some
2482 * method conform to the method they implement.
2483 * @param tree The class definition whose members are checked.
2484 */
2485 void checkImplementations(JCClassDecl tree) {
2486 checkImplementations(tree, tree.sym, tree.sym);
2487 }
2488 //where
2489 /** Check that all methods which implement some
2490 * method in `ic' conform to the method they implement.
2491 */
2492 void checkImplementations(JCTree tree, ClassSymbol origin, ClassSymbol ic) {
2493 for (List<Type> l = types.closure(ic.type); l.nonEmpty(); l = l.tail) {
2494 ClassSymbol lc = (ClassSymbol)l.head.tsym;
2495 if ((lc.flags() & ABSTRACT) != 0) {
2496 for (Symbol sym : lc.members().getSymbols(NON_RECURSIVE)) {
2497 if (sym.kind == MTH &&
2498 (sym.flags() & (STATIC|ABSTRACT)) == ABSTRACT) {
2499 MethodSymbol absmeth = (MethodSymbol)sym;
2500 MethodSymbol implmeth = absmeth.implementation(origin, types, false);
2501 if (implmeth != null && implmeth != absmeth &&
2502 (implmeth.owner.flags() & INTERFACE) ==
2503 (origin.flags() & INTERFACE)) {
2504 // don't check if implmeth is in a class, yet
2505 // origin is an interface. This case arises only
2506 // if implmeth is declared in Object. The reason is
2507 // that interfaces really don't inherit from
2508 // Object it's just that the compiler represents
2509 // things that way.
2510 checkOverride(tree, implmeth, absmeth, origin);
2511 }
2512 }
2513 }
2514 }
2515 }
2516 }
2517
2518 /** Check that all abstract methods implemented by a class are
2519 * mutually compatible.
2520 * @param pos Position to be used for error reporting.
2521 * @param c The class whose interfaces are checked.
2522 */
2523 void checkCompatibleSupertypes(DiagnosticPosition pos, Type c) {
2524 List<Type> supertypes = types.interfaces(c);
2525 Type supertype = types.supertype(c);
2526 if (supertype.hasTag(CLASS) &&
2527 (supertype.tsym.flags() & ABSTRACT) != 0)
2528 supertypes = supertypes.prepend(supertype);
2529 for (List<Type> l = supertypes; l.nonEmpty(); l = l.tail) {
2530 if (!l.head.getTypeArguments().isEmpty() &&
2531 !checkCompatibleAbstracts(pos, l.head, l.head, c))
2532 return;
2533 for (List<Type> m = supertypes; m != l; m = m.tail)
2534 if (!checkCompatibleAbstracts(pos, l.head, m.head, c))
2535 return;
2536 }
2537 checkCompatibleConcretes(pos, c);
2538 }
2539
2540 /** Check that all non-override equivalent methods accessible from 'site'
2541 * are mutually compatible (JLS 8.4.8/9.4.1).
2542 *
2543 * @param pos Position to be used for error reporting.
2544 * @param site The class whose methods are checked.
2545 * @param sym The method symbol to be checked.
2546 */
2547 void checkOverrideClashes(DiagnosticPosition pos, Type site, MethodSymbol sym) {
2548 ClashFilter cf = new ClashFilter(site);
2549 //for each method m1 that is overridden (directly or indirectly)
2550 //by method 'sym' in 'site'...
2551
2552 List<MethodSymbol> potentiallyAmbiguousList = List.nil();
2553 boolean overridesAny = false;
2554 ArrayList<Symbol> symbolsByName = new ArrayList<>();
2555 types.membersClosure(site, false).getSymbolsByName(sym.name, cf).forEach(symbolsByName::add);
2556 for (Symbol m1 : symbolsByName) {
2557 if (!sym.overrides(m1, site.tsym, types, false)) {
2558 if (m1 == sym) {
2559 continue;
2560 }
2561
2562 if (!overridesAny) {
2563 potentiallyAmbiguousList = potentiallyAmbiguousList.prepend((MethodSymbol)m1);
2564 }
2565 continue;
2566 }
2567
2568 if (m1 != sym) {
2569 overridesAny = true;
2570 potentiallyAmbiguousList = List.nil();
2571 }
2572
2573 //...check each method m2 that is a member of 'site'
2574 for (Symbol m2 : symbolsByName) {
2575 if (m2 == m1) continue;
2576 //if (i) the signature of 'sym' is not a subsignature of m1 (seen as
2577 //a member of 'site') and (ii) m1 has the same erasure as m2, issue an error
2578 if (!types.isSubSignature(sym.type, types.memberType(site, m2)) &&
2579 types.hasSameArgs(m2.erasure(types), m1.erasure(types))) {
2580 sym.flags_field |= CLASH;
2581 if (m1 == sym) {
2582 log.error(pos, Errors.NameClashSameErasureNoOverride(
2583 m1.name, types.memberType(site, m1).asMethodType().getParameterTypes(), m1.location(),
2584 m2.name, types.memberType(site, m2).asMethodType().getParameterTypes(), m2.location()));
2585 } else {
2586 ClassType ct = (ClassType)site;
2587 String kind = ct.isInterface() ? "interface" : "class";
2588 log.error(pos, Errors.NameClashSameErasureNoOverride1(
2589 kind,
2590 ct.tsym.name,
2591 m1.name,
2592 types.memberType(site, m1).asMethodType().getParameterTypes(),
2593 m1.location(),
2594 m2.name,
2595 types.memberType(site, m2).asMethodType().getParameterTypes(),
2596 m2.location()));
2597 }
2598 return;
2599 }
2600 }
2601 }
2602
2603 if (!overridesAny) {
2604 for (MethodSymbol m: potentiallyAmbiguousList) {
2605 checkPotentiallyAmbiguousOverloads(pos, site, sym, m);
2606 }
2607 }
2608 }
2609
2610 /** Check that all static methods accessible from 'site' are
2611 * mutually compatible (JLS 8.4.8).
2612 *
2613 * @param pos Position to be used for error reporting.
2614 * @param site The class whose methods are checked.
2615 * @param sym The method symbol to be checked.
2616 */
2617 void checkHideClashes(DiagnosticPosition pos, Type site, MethodSymbol sym) {
2618 ClashFilter cf = new ClashFilter(site);
2619 //for each method m1 that is a member of 'site'...
2620 for (Symbol s : types.membersClosure(site, true).getSymbolsByName(sym.name, cf)) {
2621 //if (i) the signature of 'sym' is not a subsignature of m1 (seen as
2622 //a member of 'site') and (ii) 'sym' has the same erasure as m1, issue an error
2623 if (!types.isSubSignature(sym.type, types.memberType(site, s))) {
2624 if (types.hasSameArgs(s.erasure(types), sym.erasure(types))) {
2625 log.error(pos,
2626 Errors.NameClashSameErasureNoHide(sym, sym.location(), s, s.location()));
2627 return;
2628 } else {
2629 checkPotentiallyAmbiguousOverloads(pos, site, sym, (MethodSymbol)s);
2630 }
2631 }
2632 }
2633 }
2634
2635 //where
2636 private class ClashFilter implements Predicate<Symbol> {
2637
2638 Type site;
2639
2640 ClashFilter(Type site) {
2641 this.site = site;
2642 }
2643
2644 boolean shouldSkip(Symbol s) {
2645 return (s.flags() & CLASH) != 0 &&
2646 s.owner == site.tsym;
2647 }
2648
2649 @Override
2650 public boolean test(Symbol s) {
2651 return s.kind == MTH &&
2652 (s.flags() & SYNTHETIC) == 0 &&
2653 !shouldSkip(s) &&
2654 s.isInheritedIn(site.tsym, types) &&
2655 !s.isConstructor();
2656 }
2657 }
2658
2659 void checkDefaultMethodClashes(DiagnosticPosition pos, Type site) {
2660 DefaultMethodClashFilter dcf = new DefaultMethodClashFilter(site);
2661 for (Symbol m : types.membersClosure(site, false).getSymbols(dcf)) {
2662 Assert.check(m.kind == MTH);
2663 List<MethodSymbol> prov = types.interfaceCandidates(site, (MethodSymbol)m);
2664 if (prov.size() > 1) {
2665 ListBuffer<Symbol> abstracts = new ListBuffer<>();
2666 ListBuffer<Symbol> defaults = new ListBuffer<>();
2667 for (MethodSymbol provSym : prov) {
2668 if ((provSym.flags() & DEFAULT) != 0) {
2669 defaults = defaults.append(provSym);
2670 } else if ((provSym.flags() & ABSTRACT) != 0) {
2671 abstracts = abstracts.append(provSym);
2672 }
2673 if (defaults.nonEmpty() && defaults.size() + abstracts.size() >= 2) {
2674 //strong semantics - issue an error if two sibling interfaces
2675 //have two override-equivalent defaults - or if one is abstract
2676 //and the other is default
2677 Fragment diagKey;
2678 Symbol s1 = defaults.first();
2679 Symbol s2;
2680 if (defaults.size() > 1) {
2681 s2 = defaults.toList().tail.head;
2682 diagKey = Fragments.IncompatibleUnrelatedDefaults(Kinds.kindName(site.tsym), site,
2683 m.name, types.memberType(site, m).getParameterTypes(),
2684 s1.location(), s2.location());
2685
2686 } else {
2687 s2 = abstracts.first();
2688 diagKey = Fragments.IncompatibleAbstractDefault(Kinds.kindName(site.tsym), site,
2689 m.name, types.memberType(site, m).getParameterTypes(),
2690 s1.location(), s2.location());
2691 }
2692 log.error(pos, Errors.TypesIncompatible(s1.location().type, s2.location().type, diagKey));
2693 break;
2694 }
2695 }
2696 }
2697 }
2698 }
2699
2700 //where
2701 private class DefaultMethodClashFilter implements Predicate<Symbol> {
2702
2703 Type site;
2704
2705 DefaultMethodClashFilter(Type site) {
2706 this.site = site;
2707 }
2708
2709 @Override
2710 public boolean test(Symbol s) {
2711 return s.kind == MTH &&
2712 (s.flags() & DEFAULT) != 0 &&
2713 s.isInheritedIn(site.tsym, types) &&
2714 !s.isConstructor();
2715 }
2716 }
2717
2718 /**
2719 * Report warnings for potentially ambiguous method declarations. Two declarations
2720 * are potentially ambiguous if they feature two unrelated functional interface
2721 * in same argument position (in which case, a call site passing an implicit
2722 * lambda would be ambiguous).
2723 */
2724 void checkPotentiallyAmbiguousOverloads(DiagnosticPosition pos, Type site,
2725 MethodSymbol msym1, MethodSymbol msym2) {
2726 if (msym1 != msym2 &&
2727 lint.isEnabled(LintCategory.OVERLOADS) &&
2728 (msym1.flags() & POTENTIALLY_AMBIGUOUS) == 0 &&
2729 (msym2.flags() & POTENTIALLY_AMBIGUOUS) == 0) {
2730 Type mt1 = types.memberType(site, msym1);
2731 Type mt2 = types.memberType(site, msym2);
2732 //if both generic methods, adjust type variables
2733 if (mt1.hasTag(FORALL) && mt2.hasTag(FORALL) &&
2734 types.hasSameBounds((ForAll)mt1, (ForAll)mt2)) {
2735 mt2 = types.subst(mt2, ((ForAll)mt2).tvars, ((ForAll)mt1).tvars);
2736 }
2737 //expand varargs methods if needed
2738 int maxLength = Math.max(mt1.getParameterTypes().length(), mt2.getParameterTypes().length());
2739 List<Type> args1 = rs.adjustArgs(mt1.getParameterTypes(), msym1, maxLength, true);
2740 List<Type> args2 = rs.adjustArgs(mt2.getParameterTypes(), msym2, maxLength, true);
2741 //if arities don't match, exit
2742 if (args1.length() != args2.length()) return;
2743 boolean potentiallyAmbiguous = false;
2744 while (args1.nonEmpty() && args2.nonEmpty()) {
2745 Type s = args1.head;
2746 Type t = args2.head;
2747 if (!types.isSubtype(t, s) && !types.isSubtype(s, t)) {
2748 if (types.isFunctionalInterface(s) && types.isFunctionalInterface(t) &&
2749 types.findDescriptorType(s).getParameterTypes().length() > 0 &&
2750 types.findDescriptorType(s).getParameterTypes().length() ==
2751 types.findDescriptorType(t).getParameterTypes().length()) {
2752 potentiallyAmbiguous = true;
2753 } else {
2754 return;
2755 }
2756 }
2757 args1 = args1.tail;
2758 args2 = args2.tail;
2759 }
2760 if (potentiallyAmbiguous) {
2761 //we found two incompatible functional interfaces with same arity
2762 //this means a call site passing an implicit lambda would be ambiguous
2763 msym1.flags_field |= POTENTIALLY_AMBIGUOUS;
2764 msym2.flags_field |= POTENTIALLY_AMBIGUOUS;
2765 log.warning(LintCategory.OVERLOADS, pos,
2766 Warnings.PotentiallyAmbiguousOverload(msym1, msym1.location(),
2767 msym2, msym2.location()));
2768 return;
2769 }
2770 }
2771 }
2772
2773 void checkAccessFromSerializableElement(final JCTree tree, boolean isLambda) {
2774 if (warnOnAnyAccessToMembers ||
2775 (lint.isEnabled(LintCategory.SERIAL) &&
2776 !lint.isSuppressed(LintCategory.SERIAL) &&
2777 isLambda)) {
2778 Symbol sym = TreeInfo.symbol(tree);
2779 if (!sym.kind.matches(KindSelector.VAL_MTH)) {
2780 return;
2781 }
2782
2783 if (sym.kind == VAR) {
2784 if ((sym.flags() & PARAMETER) != 0 ||
2785 sym.isDirectlyOrIndirectlyLocal() ||
2786 sym.name == names._this ||
2787 sym.name == names._super) {
2788 return;
2789 }
2790 }
2791
2792 if (!types.isSubtype(sym.owner.type, syms.serializableType) &&
2793 isEffectivelyNonPublic(sym)) {
2794 if (isLambda) {
2795 if (belongsToRestrictedPackage(sym)) {
2796 log.warning(LintCategory.SERIAL, tree.pos(),
2797 Warnings.AccessToMemberFromSerializableLambda(sym));
2798 }
2799 } else {
2800 log.warning(tree.pos(),
2801 Warnings.AccessToMemberFromSerializableElement(sym));
2802 }
2803 }
2804 }
2805 }
2806
2807 private boolean isEffectivelyNonPublic(Symbol sym) {
2808 if (sym.packge() == syms.rootPackage) {
2809 return false;
2810 }
2811
2812 while (sym.kind != PCK) {
2813 if ((sym.flags() & PUBLIC) == 0) {
2814 return true;
2815 }
2816 sym = sym.owner;
2817 }
2818 return false;
2819 }
2820
2821 private boolean belongsToRestrictedPackage(Symbol sym) {
2822 String fullName = sym.packge().fullname.toString();
2823 return fullName.startsWith("java.") ||
2824 fullName.startsWith("javax.") ||
2825 fullName.startsWith("sun.") ||
2826 fullName.contains(".internal.");
2827 }
2828
2829 /** Check that class c does not implement directly or indirectly
2830 * the same parameterized interface with two different argument lists.
2831 * @param pos Position to be used for error reporting.
2832 * @param type The type whose interfaces are checked.
2833 */
2834 void checkClassBounds(DiagnosticPosition pos, Type type) {
2835 checkClassBounds(pos, new HashMap<TypeSymbol,Type>(), type);
2836 }
2837 //where
2838 /** Enter all interfaces of type `type' into the hash table `seensofar'
2839 * with their class symbol as key and their type as value. Make
2840 * sure no class is entered with two different types.
2841 */
2842 void checkClassBounds(DiagnosticPosition pos,
2843 Map<TypeSymbol,Type> seensofar,
2844 Type type) {
2845 if (type.isErroneous()) return;
2846 for (List<Type> l = types.interfaces(type); l.nonEmpty(); l = l.tail) {
2847 Type it = l.head;
2848 if (type.hasTag(CLASS) && !it.hasTag(CLASS)) continue; // JLS 8.1.5
2849
2850 Type oldit = seensofar.put(it.tsym, it);
2851 if (oldit != null) {
2852 List<Type> oldparams = oldit.allparams();
2853 List<Type> newparams = it.allparams();
2854 if (!types.containsTypeEquivalent(oldparams, newparams))
2855 log.error(pos,
2856 Errors.CantInheritDiffArg(it.tsym,
2857 Type.toString(oldparams),
2858 Type.toString(newparams)));
2859 }
2860 checkClassBounds(pos, seensofar, it);
2861 }
2862 Type st = types.supertype(type);
2863 if (type.hasTag(CLASS) && !st.hasTag(CLASS)) return; // JLS 8.1.4
2864 if (st != Type.noType) checkClassBounds(pos, seensofar, st);
2865 }
2866
2867 /** Enter interface into into set.
2868 * If it existed already, issue a "repeated interface" error.
2869 */
2870 void checkNotRepeated(DiagnosticPosition pos, Type it, Set<Type> its) {
2871 if (its.contains(it))
2872 log.error(pos, Errors.RepeatedInterface);
2873 else {
2874 its.add(it);
2875 }
2876 }
2877
2878 /* *************************************************************************
2879 * Check annotations
2880 **************************************************************************/
2881
2882 /**
2883 * Recursively validate annotations values
2884 */
2885 void validateAnnotationTree(JCTree tree) {
2886 class AnnotationValidator extends TreeScanner {
2887 @Override
2888 public void visitAnnotation(JCAnnotation tree) {
2889 if (!tree.type.isErroneous() && tree.type.tsym.isAnnotationType()) {
2890 super.visitAnnotation(tree);
2891 validateAnnotation(tree);
2892 }
2893 }
2894 }
2895 tree.accept(new AnnotationValidator());
2896 }
2897
2898 /**
2899 * {@literal
2900 * Annotation types are restricted to primitives, String, an
2901 * enum, an annotation, Class, Class<?>, Class<? extends
2902 * Anything>, arrays of the preceding.
2903 * }
2904 */
2905 void validateAnnotationType(JCTree restype) {
2906 // restype may be null if an error occurred, so don't bother validating it
2907 if (restype != null) {
2908 validateAnnotationType(restype.pos(), restype.type);
2909 }
2910 }
2911
2912 void validateAnnotationType(DiagnosticPosition pos, Type type) {
2913 if (type.isPrimitive()) return;
2914 if (types.isSameType(type, syms.stringType)) return;
2915 if ((type.tsym.flags() & Flags.ENUM) != 0) return;
2916 if ((type.tsym.flags() & Flags.ANNOTATION) != 0) return;
2917 if (types.cvarLowerBound(type).tsym == syms.classType.tsym) return;
2918 if (types.isArray(type) && !types.isArray(types.elemtype(type))) {
2919 validateAnnotationType(pos, types.elemtype(type));
2920 return;
2921 }
2922 log.error(pos, Errors.InvalidAnnotationMemberType);
2923 }
2924
2925 /**
2926 * "It is also a compile-time error if any method declared in an
2927 * annotation type has a signature that is override-equivalent to
2928 * that of any public or protected method declared in class Object
2929 * or in the interface annotation.Annotation."
2930 *
2931 * @jls 9.6 Annotation Types
2932 */
2933 void validateAnnotationMethod(DiagnosticPosition pos, MethodSymbol m) {
2934 for (Type sup = syms.annotationType; sup.hasTag(CLASS); sup = types.supertype(sup)) {
2935 Scope s = sup.tsym.members();
2936 for (Symbol sym : s.getSymbolsByName(m.name)) {
2937 if (sym.kind == MTH &&
2938 (sym.flags() & (PUBLIC | PROTECTED)) != 0 &&
2939 types.overrideEquivalent(m.type, sym.type))
2940 log.error(pos, Errors.IntfAnnotationMemberClash(sym, sup));
2941 }
2942 }
2943 }
2944
2945 /** Check the annotations of a symbol.
2946 */
2947 public void validateAnnotations(List<JCAnnotation> annotations, JCTree declarationTree, Symbol s) {
2948 for (JCAnnotation a : annotations)
2949 validateAnnotation(a, declarationTree, s);
2950 }
2951
2952 /** Check the type annotations.
2953 */
2954 public void validateTypeAnnotations(List<JCAnnotation> annotations, boolean isTypeParameter) {
2955 for (JCAnnotation a : annotations)
2956 validateTypeAnnotation(a, isTypeParameter);
2957 }
2958
2959 /** Check an annotation of a symbol.
2960 */
2961 private void validateAnnotation(JCAnnotation a, JCTree declarationTree, Symbol s) {
2962 /** NOTE: if annotation processors are present, annotation processing rounds can happen after this method,
2963 * this can impact in particular records for which annotations are forcibly propagated.
2964 */
2965 validateAnnotationTree(a);
2966 boolean isRecordMember = ((s.flags_field & RECORD) != 0 || s.enclClass() != null && s.enclClass().isRecord());
2967
2968 boolean isRecordField = (s.flags_field & RECORD) != 0 &&
2969 declarationTree.hasTag(VARDEF) &&
2970 s.owner.kind == TYP;
2971
2972 if (isRecordField) {
2973 // first we need to check if the annotation is applicable to records
2974 Name[] targets = getTargetNames(a);
2975 boolean appliesToRecords = false;
2976 for (Name target : targets) {
2977 appliesToRecords =
2978 target == names.FIELD ||
2979 target == names.PARAMETER ||
2980 target == names.METHOD ||
2981 target == names.TYPE_USE ||
2982 target == names.RECORD_COMPONENT;
2983 if (appliesToRecords) {
2984 break;
2985 }
2986 }
2987 if (!appliesToRecords) {
2988 log.error(a.pos(), Errors.AnnotationTypeNotApplicable);
2989 } else {
2990 /* lets now find the annotations in the field that are targeted to record components and append them to
2991 * the corresponding record component
2992 */
2993 ClassSymbol recordClass = (ClassSymbol) s.owner;
2994 RecordComponent rc = recordClass.getRecordComponent((VarSymbol)s);
2995 SymbolMetadata metadata = rc.getMetadata();
2996 if (metadata == null || metadata.isEmpty()) {
2997 /* if not is empty then we have already been here, which is the case if multiple annotations are applied
2998 * to the record component declaration
2999 */
3000 rc.appendAttributes(s.getRawAttributes().stream().filter(anno ->
3001 Arrays.stream(getTargetNames(anno.type.tsym)).anyMatch(name -> name == names.RECORD_COMPONENT)
3002 ).collect(List.collector()));
3003 rc.setTypeAttributes(s.getRawTypeAttributes());
3004 // to get all the type annotations applied to the type
3005 rc.type = s.type;
3006 }
3007 }
3008 }
3009
3010 /* the section below is tricky. Annotations applied to record components are propagated to the corresponding
3011 * record member so if an annotation has target: FIELD, it is propagated to the corresponding FIELD, if it has
3012 * target METHOD, it is propagated to the accessor and so on. But at the moment when method members are generated
3013 * there is no enough information to propagate only the right annotations. So all the annotations are propagated
3014 * to all the possible locations.
3015 *
3016 * At this point we need to remove all the annotations that are not in place before going on with the annotation
3017 * party. On top of the above there is the issue that there is no AST representing record components, just symbols
3018 * so the corresponding field has been holding all the annotations and it's metadata has been modified as if it
3019 * was both a field and a record component.
3020 *
3021 * So there are two places where we need to trim annotations from: the metadata of the symbol and / or the modifiers
3022 * in the AST. Whatever is in the metadata will be written to the class file, whatever is in the modifiers could
3023 * be see by annotation processors.
3024 *
3025 * The metadata contains both type annotations and declaration annotations. At this point of the game we don't
3026 * need to care about type annotations, they are all in the right place. But we could need to remove declaration
3027 * annotations. So for declaration annotations if they are not applicable to the record member, excluding type
3028 * annotations which are already correct, then we will remove it. For the AST modifiers if the annotation is not
3029 * applicable either as type annotation and or declaration annotation, only in that case it will be removed.
3030 *
3031 * So it could be that annotation is removed as a declaration annotation but it is kept in the AST modifier for
3032 * further inspection by annotation processors.
3033 *
3034 * For example:
3035 *
3036 * import java.lang.annotation.*;
3037 *
3038 * @Target({ElementType.TYPE_USE, ElementType.RECORD_COMPONENT})
3039 * @Retention(RetentionPolicy.RUNTIME)
3040 * @interface Anno { }
3041 *
3042 * record R(@Anno String s) {}
3043 *
3044 * at this point we will have for the case of the generated field:
3045 * - @Anno in the modifier
3046 * - @Anno as a type annotation
3047 * - @Anno as a declaration annotation
3048 *
3049 * the last one should be removed because the annotation has not FIELD as target but it was applied as a
3050 * declaration annotation because the field was being treated both as a field and as a record component
3051 * as we have already copied the annotations to the record component, now the field doesn't need to hold
3052 * annotations that are not intended for it anymore. Still @Anno has to be kept in the AST's modifiers as it
3053 * is applicable as a type annotation to the type of the field.
3054 */
3055
3056 if (a.type.tsym.isAnnotationType()) {
3057 Optional<Set<Name>> applicableTargetsOp = getApplicableTargets(a, s);
3058 if (!applicableTargetsOp.isEmpty()) {
3059 Set<Name> applicableTargets = applicableTargetsOp.get();
3060 boolean notApplicableOrIsTypeUseOnly = applicableTargets.isEmpty() ||
3061 applicableTargets.size() == 1 && applicableTargets.contains(names.TYPE_USE);
3062 boolean isCompGeneratedRecordElement = isRecordMember && (s.flags_field & Flags.GENERATED_MEMBER) != 0;
3063 boolean isCompRecordElementWithNonApplicableDeclAnno = isCompGeneratedRecordElement && notApplicableOrIsTypeUseOnly;
3064
3065 if (applicableTargets.isEmpty() || isCompRecordElementWithNonApplicableDeclAnno) {
3066 if (isCompRecordElementWithNonApplicableDeclAnno) {
3067 /* so we have found an annotation that is not applicable to a record member that was generated by the
3068 * compiler. This was intentionally done at TypeEnter, now is the moment strip away the annotations
3069 * that are not applicable to the given record member
3070 */
3071 JCModifiers modifiers = TreeInfo.getModifiers(declarationTree);
3072 /* lets first remove the annotation from the modifier if it is not applicable, we have to check again as
3073 * it could be a type annotation
3074 */
3075 if (modifiers != null && applicableTargets.isEmpty()) {
3076 ListBuffer<JCAnnotation> newAnnotations = new ListBuffer<>();
3077 for (JCAnnotation anno : modifiers.annotations) {
3078 if (anno != a) {
3079 newAnnotations.add(anno);
3080 }
3081 }
3082 modifiers.annotations = newAnnotations.toList();
3083 }
3084 // now lets remove it from the symbol
3085 s.getMetadata().removeDeclarationMetadata(a.attribute);
3086 } else {
3087 log.error(a.pos(), Errors.AnnotationTypeNotApplicable);
3088 }
3089 }
3090 /* if we are seeing the @SafeVarargs annotation applied to a compiler generated accessor,
3091 * then this is an error as we know that no compiler generated accessor will be a varargs
3092 * method, better to fail asap
3093 */
3094 if (isCompGeneratedRecordElement && !isRecordField && a.type.tsym == syms.trustMeType.tsym && declarationTree.hasTag(METHODDEF)) {
3095 log.error(a.pos(), Errors.VarargsInvalidTrustmeAnno(syms.trustMeType.tsym, Fragments.VarargsTrustmeOnNonVarargsAccessor(s)));
3096 }
3097 }
3098 }
3099
3100 if (a.annotationType.type.tsym == syms.functionalInterfaceType.tsym) {
3101 if (s.kind != TYP) {
3102 log.error(a.pos(), Errors.BadFunctionalIntfAnno);
3103 } else if (!s.isInterface() || (s.flags() & ANNOTATION) != 0) {
3104 log.error(a.pos(), Errors.BadFunctionalIntfAnno1(Fragments.NotAFunctionalIntf(s)));
3105 }
3106 }
3107 }
3108
3109 public void validateTypeAnnotation(JCAnnotation a, boolean isTypeParameter) {
3110 Assert.checkNonNull(a.type);
3111 validateAnnotationTree(a);
3112
3113 if (a.hasTag(TYPE_ANNOTATION) &&
3114 !a.annotationType.type.isErroneous() &&
3115 !isTypeAnnotation(a, isTypeParameter)) {
3116 log.error(a.pos(), Errors.AnnotationTypeNotApplicableToType(a.type));
3117 }
3118 }
3119
3120 /**
3121 * Validate the proposed container 'repeatable' on the
3122 * annotation type symbol 's'. Report errors at position
3123 * 'pos'.
3124 *
3125 * @param s The (annotation)type declaration annotated with a @Repeatable
3126 * @param repeatable the @Repeatable on 's'
3127 * @param pos where to report errors
3128 */
3129 public void validateRepeatable(TypeSymbol s, Attribute.Compound repeatable, DiagnosticPosition pos) {
3130 Assert.check(types.isSameType(repeatable.type, syms.repeatableType));
3131
3132 Type t = null;
3133 List<Pair<MethodSymbol,Attribute>> l = repeatable.values;
3134 if (!l.isEmpty()) {
3135 Assert.check(l.head.fst.name == names.value);
3136 if (l.head.snd instanceof Attribute.Class) {
3137 t = ((Attribute.Class)l.head.snd).getValue();
3138 }
3139 }
3140
3141 if (t == null) {
3142 // errors should already have been reported during Annotate
3143 return;
3144 }
3145
3146 validateValue(t.tsym, s, pos);
3147 validateRetention(t.tsym, s, pos);
3148 validateDocumented(t.tsym, s, pos);
3149 validateInherited(t.tsym, s, pos);
3150 validateTarget(t.tsym, s, pos);
3151 validateDefault(t.tsym, pos);
3152 }
3153
3154 private void validateValue(TypeSymbol container, TypeSymbol contained, DiagnosticPosition pos) {
3155 Symbol sym = container.members().findFirst(names.value);
3156 if (sym != null && sym.kind == MTH) {
3157 MethodSymbol m = (MethodSymbol) sym;
3158 Type ret = m.getReturnType();
3159 if (!(ret.hasTag(ARRAY) && types.isSameType(((ArrayType)ret).elemtype, contained.type))) {
3160 log.error(pos,
3161 Errors.InvalidRepeatableAnnotationValueReturn(container,
3162 ret,
3163 types.makeArrayType(contained.type)));
3164 }
3165 } else {
3166 log.error(pos, Errors.InvalidRepeatableAnnotationNoValue(container));
3167 }
3168 }
3169
3170 private void validateRetention(TypeSymbol container, TypeSymbol contained, DiagnosticPosition pos) {
3171 Attribute.RetentionPolicy containerRetention = types.getRetention(container);
3172 Attribute.RetentionPolicy containedRetention = types.getRetention(contained);
3173
3174 boolean error = false;
3175 switch (containedRetention) {
3176 case RUNTIME:
3177 if (containerRetention != Attribute.RetentionPolicy.RUNTIME) {
3178 error = true;
3179 }
3180 break;
3181 case CLASS:
3182 if (containerRetention == Attribute.RetentionPolicy.SOURCE) {
3183 error = true;
3184 }
3185 }
3186 if (error ) {
3187 log.error(pos,
3188 Errors.InvalidRepeatableAnnotationRetention(container,
3189 containerRetention.name(),
3190 contained,
3191 containedRetention.name()));
3192 }
3193 }
3194
3195 private void validateDocumented(Symbol container, Symbol contained, DiagnosticPosition pos) {
3196 if (contained.attribute(syms.documentedType.tsym) != null) {
3197 if (container.attribute(syms.documentedType.tsym) == null) {
3198 log.error(pos, Errors.InvalidRepeatableAnnotationNotDocumented(container, contained));
3199 }
3200 }
3201 }
3202
3203 private void validateInherited(Symbol container, Symbol contained, DiagnosticPosition pos) {
3204 if (contained.attribute(syms.inheritedType.tsym) != null) {
3205 if (container.attribute(syms.inheritedType.tsym) == null) {
3206 log.error(pos, Errors.InvalidRepeatableAnnotationNotInherited(container, contained));
3207 }
3208 }
3209 }
3210
3211 private void validateTarget(TypeSymbol container, TypeSymbol contained, DiagnosticPosition pos) {
3212 // The set of targets the container is applicable to must be a subset
3213 // (with respect to annotation target semantics) of the set of targets
3214 // the contained is applicable to. The target sets may be implicit or
3215 // explicit.
3216
3217 Set<Name> containerTargets;
3218 Attribute.Array containerTarget = getAttributeTargetAttribute(container);
3219 if (containerTarget == null) {
3220 containerTargets = getDefaultTargetSet();
3221 } else {
3222 containerTargets = new HashSet<>();
3223 for (Attribute app : containerTarget.values) {
3224 if (!(app instanceof Attribute.Enum attributeEnum)) {
3225 continue; // recovery
3226 }
3227 containerTargets.add(attributeEnum.value.name);
3228 }
3229 }
3230
3231 Set<Name> containedTargets;
3232 Attribute.Array containedTarget = getAttributeTargetAttribute(contained);
3233 if (containedTarget == null) {
3234 containedTargets = getDefaultTargetSet();
3235 } else {
3236 containedTargets = new HashSet<>();
3237 for (Attribute app : containedTarget.values) {
3238 if (!(app instanceof Attribute.Enum attributeEnum)) {
3239 continue; // recovery
3240 }
3241 containedTargets.add(attributeEnum.value.name);
3242 }
3243 }
3244
3245 if (!isTargetSubsetOf(containerTargets, containedTargets)) {
3246 log.error(pos, Errors.InvalidRepeatableAnnotationIncompatibleTarget(container, contained));
3247 }
3248 }
3249
3250 /* get a set of names for the default target */
3251 private Set<Name> getDefaultTargetSet() {
3252 if (defaultTargets == null) {
3253 defaultTargets = Set.of(defaultTargetMetaInfo());
3254 }
3255
3256 return defaultTargets;
3257 }
3258 private Set<Name> defaultTargets;
3259
3260
3261 /** Checks that s is a subset of t, with respect to ElementType
3262 * semantics, specifically {ANNOTATION_TYPE} is a subset of {TYPE},
3263 * and {TYPE_USE} covers the set {ANNOTATION_TYPE, TYPE, TYPE_USE,
3264 * TYPE_PARAMETER}.
3265 */
3266 private boolean isTargetSubsetOf(Set<Name> s, Set<Name> t) {
3267 // Check that all elements in s are present in t
3268 for (Name n2 : s) {
3269 boolean currentElementOk = false;
3270 for (Name n1 : t) {
3271 if (n1 == n2) {
3272 currentElementOk = true;
3273 break;
3274 } else if (n1 == names.TYPE && n2 == names.ANNOTATION_TYPE) {
3275 currentElementOk = true;
3276 break;
3277 } else if (n1 == names.TYPE_USE &&
3278 (n2 == names.TYPE ||
3279 n2 == names.ANNOTATION_TYPE ||
3280 n2 == names.TYPE_PARAMETER)) {
3281 currentElementOk = true;
3282 break;
3283 }
3284 }
3285 if (!currentElementOk)
3286 return false;
3287 }
3288 return true;
3289 }
3290
3291 private void validateDefault(Symbol container, DiagnosticPosition pos) {
3292 // validate that all other elements of containing type has defaults
3293 Scope scope = container.members();
3294 for(Symbol elm : scope.getSymbols()) {
3295 if (elm.name != names.value &&
3296 elm.kind == MTH &&
3297 ((MethodSymbol)elm).defaultValue == null) {
3298 log.error(pos,
3299 Errors.InvalidRepeatableAnnotationElemNondefault(container, elm));
3300 }
3301 }
3302 }
3303
3304 /** Is s a method symbol that overrides a method in a superclass? */
3305 boolean isOverrider(Symbol s) {
3306 if (s.kind != MTH || s.isStatic())
3307 return false;
3308 MethodSymbol m = (MethodSymbol)s;
3309 TypeSymbol owner = (TypeSymbol)m.owner;
3310 for (Type sup : types.closure(owner.type)) {
3311 if (sup == owner.type)
3312 continue; // skip "this"
3313 Scope scope = sup.tsym.members();
3314 for (Symbol sym : scope.getSymbolsByName(m.name)) {
3315 if (!sym.isStatic() && m.overrides(sym, owner, types, true))
3316 return true;
3317 }
3318 }
3319 return false;
3320 }
3321
3322 /** Is the annotation applicable to types? */
3323 protected boolean isTypeAnnotation(JCAnnotation a, boolean isTypeParameter) {
3324 List<Attribute> targets = typeAnnotations.annotationTargets(a.annotationType.type.tsym);
3325 return (targets == null) ?
3326 false :
3327 targets.stream()
3328 .anyMatch(attr -> isTypeAnnotation(attr, isTypeParameter));
3329 }
3330 //where
3331 boolean isTypeAnnotation(Attribute a, boolean isTypeParameter) {
3332 Attribute.Enum e = (Attribute.Enum)a;
3333 return (e.value.name == names.TYPE_USE ||
3334 (isTypeParameter && e.value.name == names.TYPE_PARAMETER));
3335 }
3336
3337 /** Is the annotation applicable to the symbol? */
3338 Name[] getTargetNames(JCAnnotation a) {
3339 return getTargetNames(a.annotationType.type.tsym);
3340 }
3341
3342 public Name[] getTargetNames(TypeSymbol annoSym) {
3343 Attribute.Array arr = getAttributeTargetAttribute(annoSym);
3344 Name[] targets;
3345 if (arr == null) {
3346 targets = defaultTargetMetaInfo();
3347 } else {
3348 // TODO: can we optimize this?
3349 targets = new Name[arr.values.length];
3350 for (int i=0; i<arr.values.length; ++i) {
3351 Attribute app = arr.values[i];
3352 if (!(app instanceof Attribute.Enum attributeEnum)) {
3353 return new Name[0];
3354 }
3355 targets[i] = attributeEnum.value.name;
3356 }
3357 }
3358 return targets;
3359 }
3360
3361 boolean annotationApplicable(JCAnnotation a, Symbol s) {
3362 Optional<Set<Name>> targets = getApplicableTargets(a, s);
3363 /* the optional could be empty if the annotation is unknown in that case
3364 * we return that it is applicable and if it is erroneous that should imply
3365 * an error at the declaration site
3366 */
3367 return targets.isEmpty() || targets.isPresent() && !targets.get().isEmpty();
3368 }
3369
3370 Optional<Set<Name>> getApplicableTargets(JCAnnotation a, Symbol s) {
3371 Attribute.Array arr = getAttributeTargetAttribute(a.annotationType.type.tsym);
3372 Name[] targets;
3373 Set<Name> applicableTargets = new HashSet<>();
3374
3375 if (arr == null) {
3376 targets = defaultTargetMetaInfo();
3377 } else {
3378 // TODO: can we optimize this?
3379 targets = new Name[arr.values.length];
3380 for (int i=0; i<arr.values.length; ++i) {
3381 Attribute app = arr.values[i];
3382 if (!(app instanceof Attribute.Enum attributeEnum)) {
3383 // recovery
3384 return Optional.empty();
3385 }
3386 targets[i] = attributeEnum.value.name;
3387 }
3388 }
3389 for (Name target : targets) {
3390 if (target == names.TYPE) {
3391 if (s.kind == TYP)
3392 applicableTargets.add(names.TYPE);
3393 } else if (target == names.FIELD) {
3394 if (s.kind == VAR && s.owner.kind != MTH)
3395 applicableTargets.add(names.FIELD);
3396 } else if (target == names.RECORD_COMPONENT) {
3397 if (s.getKind() == ElementKind.RECORD_COMPONENT) {
3398 applicableTargets.add(names.RECORD_COMPONENT);
3399 }
3400 } else if (target == names.METHOD) {
3401 if (s.kind == MTH && !s.isConstructor())
3402 applicableTargets.add(names.METHOD);
3403 } else if (target == names.PARAMETER) {
3404 if (s.kind == VAR &&
3405 (s.owner.kind == MTH && (s.flags() & PARAMETER) != 0)) {
3406 applicableTargets.add(names.PARAMETER);
3407 }
3408 } else if (target == names.CONSTRUCTOR) {
3409 if (s.kind == MTH && s.isConstructor())
3410 applicableTargets.add(names.CONSTRUCTOR);
3411 } else if (target == names.LOCAL_VARIABLE) {
3412 if (s.kind == VAR && s.owner.kind == MTH &&
3413 (s.flags() & PARAMETER) == 0) {
3414 applicableTargets.add(names.LOCAL_VARIABLE);
3415 }
3416 } else if (target == names.ANNOTATION_TYPE) {
3417 if (s.kind == TYP && (s.flags() & ANNOTATION) != 0) {
3418 applicableTargets.add(names.ANNOTATION_TYPE);
3419 }
3420 } else if (target == names.PACKAGE) {
3421 if (s.kind == PCK)
3422 applicableTargets.add(names.PACKAGE);
3423 } else if (target == names.TYPE_USE) {
3424 if (s.kind == VAR && s.owner.kind == MTH && s.type.hasTag(NONE)) {
3425 //cannot type annotate implicitly typed locals
3426 continue;
3427 } else if (s.kind == TYP || s.kind == VAR ||
3428 (s.kind == MTH && !s.isConstructor() &&
3429 !s.type.getReturnType().hasTag(VOID)) ||
3430 (s.kind == MTH && s.isConstructor())) {
3431 applicableTargets.add(names.TYPE_USE);
3432 }
3433 } else if (target == names.TYPE_PARAMETER) {
3434 if (s.kind == TYP && s.type.hasTag(TYPEVAR))
3435 applicableTargets.add(names.TYPE_PARAMETER);
3436 } else if (target == names.MODULE) {
3437 if (s.kind == MDL)
3438 applicableTargets.add(names.MODULE);
3439 } else
3440 return Optional.empty(); // Unknown ElementType. This should be an error at declaration site,
3441 // assume applicable.
3442 }
3443 return Optional.of(applicableTargets);
3444 }
3445
3446 Attribute.Array getAttributeTargetAttribute(TypeSymbol s) {
3447 Attribute.Compound atTarget = s.getAnnotationTypeMetadata().getTarget();
3448 if (atTarget == null) return null; // ok, is applicable
3449 Attribute atValue = atTarget.member(names.value);
3450 return (atValue instanceof Attribute.Array attributeArray) ? attributeArray : null;
3451 }
3452
3453 private Name[] dfltTargetMeta;
3454 private Name[] defaultTargetMetaInfo() {
3455 if (dfltTargetMeta == null) {
3456 ArrayList<Name> defaultTargets = new ArrayList<>();
3457 defaultTargets.add(names.PACKAGE);
3458 defaultTargets.add(names.TYPE);
3459 defaultTargets.add(names.FIELD);
3460 defaultTargets.add(names.METHOD);
3461 defaultTargets.add(names.CONSTRUCTOR);
3462 defaultTargets.add(names.ANNOTATION_TYPE);
3463 defaultTargets.add(names.LOCAL_VARIABLE);
3464 defaultTargets.add(names.PARAMETER);
3465 if (allowRecords) {
3466 defaultTargets.add(names.RECORD_COMPONENT);
3467 }
3468 if (allowModules) {
3469 defaultTargets.add(names.MODULE);
3470 }
3471 dfltTargetMeta = defaultTargets.toArray(new Name[0]);
3472 }
3473 return dfltTargetMeta;
3474 }
3475
3476 /** Check an annotation value.
3477 *
3478 * @param a The annotation tree to check
3479 * @return true if this annotation tree is valid, otherwise false
3480 */
3481 public boolean validateAnnotationDeferErrors(JCAnnotation a) {
3482 boolean res = false;
3483 final Log.DiagnosticHandler diagHandler = new Log.DiscardDiagnosticHandler(log);
3484 try {
3485 res = validateAnnotation(a);
3486 } finally {
3487 log.popDiagnosticHandler(diagHandler);
3488 }
3489 return res;
3490 }
3491
3492 private boolean validateAnnotation(JCAnnotation a) {
3493 boolean isValid = true;
3494 AnnotationTypeMetadata metadata = a.annotationType.type.tsym.getAnnotationTypeMetadata();
3495
3496 // collect an inventory of the annotation elements
3497 Set<MethodSymbol> elements = metadata.getAnnotationElements();
3498
3499 // remove the ones that are assigned values
3500 for (JCTree arg : a.args) {
3501 if (!arg.hasTag(ASSIGN)) continue; // recovery
3502 JCAssign assign = (JCAssign)arg;
3503 Symbol m = TreeInfo.symbol(assign.lhs);
3504 if (m == null || m.type.isErroneous()) continue;
3505 if (!elements.remove(m)) {
3506 isValid = false;
3507 log.error(assign.lhs.pos(),
3508 Errors.DuplicateAnnotationMemberValue(m.name, a.type));
3509 }
3510 }
3511
3512 // all the remaining ones better have default values
3513 List<Name> missingDefaults = List.nil();
3514 Set<MethodSymbol> membersWithDefault = metadata.getAnnotationElementsWithDefault();
3515 for (MethodSymbol m : elements) {
3516 if (m.type.isErroneous())
3517 continue;
3518
3519 if (!membersWithDefault.contains(m))
3520 missingDefaults = missingDefaults.append(m.name);
3521 }
3522 missingDefaults = missingDefaults.reverse();
3523 if (missingDefaults.nonEmpty()) {
3524 isValid = false;
3525 Error errorKey = (missingDefaults.size() > 1)
3526 ? Errors.AnnotationMissingDefaultValue1(a.type, missingDefaults)
3527 : Errors.AnnotationMissingDefaultValue(a.type, missingDefaults);
3528 log.error(a.pos(), errorKey);
3529 }
3530
3531 return isValid && validateTargetAnnotationValue(a);
3532 }
3533
3534 /* Validate the special java.lang.annotation.Target annotation */
3535 boolean validateTargetAnnotationValue(JCAnnotation a) {
3536 // special case: java.lang.annotation.Target must not have
3537 // repeated values in its value member
3538 if (a.annotationType.type.tsym != syms.annotationTargetType.tsym ||
3539 a.args.tail == null)
3540 return true;
3541
3542 boolean isValid = true;
3543 if (!a.args.head.hasTag(ASSIGN)) return false; // error recovery
3544 JCAssign assign = (JCAssign) a.args.head;
3545 Symbol m = TreeInfo.symbol(assign.lhs);
3546 if (m.name != names.value) return false;
3547 JCTree rhs = assign.rhs;
3548 if (!rhs.hasTag(NEWARRAY)) return false;
3549 JCNewArray na = (JCNewArray) rhs;
3550 Set<Symbol> targets = new HashSet<>();
3551 for (JCTree elem : na.elems) {
3552 if (!targets.add(TreeInfo.symbol(elem))) {
3553 isValid = false;
3554 log.error(elem.pos(), Errors.RepeatedAnnotationTarget);
3555 }
3556 }
3557 return isValid;
3558 }
3559
3560 void checkDeprecatedAnnotation(DiagnosticPosition pos, Symbol s) {
3561 if (lint.isEnabled(LintCategory.DEP_ANN) && s.isDeprecatableViaAnnotation() &&
3562 (s.flags() & DEPRECATED) != 0 &&
3563 !syms.deprecatedType.isErroneous() &&
3564 s.attribute(syms.deprecatedType.tsym) == null) {
3565 log.warning(LintCategory.DEP_ANN,
3566 pos, Warnings.MissingDeprecatedAnnotation);
3567 }
3568 // Note: @Deprecated has no effect on local variables, parameters and package decls.
3569 if (lint.isEnabled(LintCategory.DEPRECATION) && !s.isDeprecatableViaAnnotation()) {
3570 if (!syms.deprecatedType.isErroneous() && s.attribute(syms.deprecatedType.tsym) != null) {
3571 log.warning(LintCategory.DEPRECATION, pos,
3572 Warnings.DeprecatedAnnotationHasNoEffect(Kinds.kindName(s)));
3573 }
3574 }
3575 }
3576
3577 void checkDeprecated(final DiagnosticPosition pos, final Symbol other, final Symbol s) {
3578 checkDeprecated(() -> pos, other, s);
3579 }
3580
3581 void checkDeprecated(Supplier<DiagnosticPosition> pos, final Symbol other, final Symbol s) {
3582 if ( (s.isDeprecatedForRemoval()
3583 || s.isDeprecated() && !other.isDeprecated())
3584 && (s.outermostClass() != other.outermostClass() || s.outermostClass() == null)
3585 && s.kind != Kind.PCK) {
3586 deferredLintHandler.report(() -> warnDeprecated(pos.get(), s));
3587 }
3588 }
3589
3590 void checkSunAPI(final DiagnosticPosition pos, final Symbol s) {
3591 if ((s.flags() & PROPRIETARY) != 0) {
3592 deferredLintHandler.report(() -> {
3593 log.mandatoryWarning(pos, Warnings.SunProprietary(s));
3594 });
3595 }
3596 }
3597
3598 void checkProfile(final DiagnosticPosition pos, final Symbol s) {
3599 if (profile != Profile.DEFAULT && (s.flags() & NOT_IN_PROFILE) != 0) {
3600 log.error(pos, Errors.NotInProfile(s, profile));
3601 }
3602 }
3603
3604 void checkPreview(DiagnosticPosition pos, Symbol other, Symbol s) {
3605 if ((s.flags() & PREVIEW_API) != 0 && !preview.participatesInPreview(syms, other, s)) {
3606 if ((s.flags() & PREVIEW_REFLECTIVE) == 0) {
3607 if (!preview.isEnabled()) {
3608 log.error(pos, Errors.IsPreview(s));
3609 } else {
3610 preview.markUsesPreview(pos);
3611 deferredLintHandler.report(() -> warnPreviewAPI(pos, Warnings.IsPreview(s)));
3612 }
3613 } else {
3614 deferredLintHandler.report(() -> warnPreviewAPI(pos, Warnings.IsPreviewReflective(s)));
3615 }
3616 }
3617 if (preview.declaredUsingPreviewFeature(s)) {
3618 if (preview.isEnabled()) {
3619 //for preview disabled do presumably so not need to do anything?
3620 //If "s" is compiled from source, then there was an error for it already;
3621 //if "s" is from classfile, there already was an error for the classfile.
3622 preview.markUsesPreview(pos);
3623 deferredLintHandler.report(() -> warnDeclaredUsingPreview(pos, s));
3624 }
3625 }
3626 }
3627
3628 /* *************************************************************************
3629 * Check for recursive annotation elements.
3630 **************************************************************************/
3631
3632 /** Check for cycles in the graph of annotation elements.
3633 */
3634 void checkNonCyclicElements(JCClassDecl tree) {
3635 if ((tree.sym.flags_field & ANNOTATION) == 0) return;
3636 Assert.check((tree.sym.flags_field & LOCKED) == 0);
3637 try {
3638 tree.sym.flags_field |= LOCKED;
3639 for (JCTree def : tree.defs) {
3640 if (!def.hasTag(METHODDEF)) continue;
3641 JCMethodDecl meth = (JCMethodDecl)def;
3642 checkAnnotationResType(meth.pos(), meth.restype.type);
3643 }
3644 } finally {
3645 tree.sym.flags_field &= ~LOCKED;
3646 tree.sym.flags_field |= ACYCLIC_ANN;
3647 }
3648 }
3649
3650 void checkNonCyclicElementsInternal(DiagnosticPosition pos, TypeSymbol tsym) {
3651 if ((tsym.flags_field & ACYCLIC_ANN) != 0)
3652 return;
3653 if ((tsym.flags_field & LOCKED) != 0) {
3654 log.error(pos, Errors.CyclicAnnotationElement(tsym));
3655 return;
3656 }
3657 try {
3658 tsym.flags_field |= LOCKED;
3659 for (Symbol s : tsym.members().getSymbols(NON_RECURSIVE)) {
3660 if (s.kind != MTH)
3661 continue;
3662 checkAnnotationResType(pos, ((MethodSymbol)s).type.getReturnType());
3663 }
3664 } finally {
3665 tsym.flags_field &= ~LOCKED;
3666 tsym.flags_field |= ACYCLIC_ANN;
3667 }
3668 }
3669
3670 void checkAnnotationResType(DiagnosticPosition pos, Type type) {
3671 switch (type.getTag()) {
3672 case CLASS:
3673 if ((type.tsym.flags() & ANNOTATION) != 0)
3674 checkNonCyclicElementsInternal(pos, type.tsym);
3675 break;
3676 case ARRAY:
3677 checkAnnotationResType(pos, types.elemtype(type));
3678 break;
3679 default:
3680 break; // int etc
3681 }
3682 }
3683
3684 /* *************************************************************************
3685 * Check for cycles in the constructor call graph.
3686 **************************************************************************/
3687
3688 /** Check for cycles in the graph of constructors calling other
3689 * constructors.
3690 */
3691 void checkCyclicConstructors(JCClassDecl tree) {
3692 Map<Symbol,Symbol> callMap = new HashMap<>();
3693
3694 // enter each constructor this-call into the map
3695 for (List<JCTree> l = tree.defs; l.nonEmpty(); l = l.tail) {
3696 JCMethodInvocation app = TreeInfo.firstConstructorCall(l.head);
3697 if (app == null) continue;
3698 JCMethodDecl meth = (JCMethodDecl) l.head;
3699 if (TreeInfo.name(app.meth) == names._this) {
3700 callMap.put(meth.sym, TreeInfo.symbol(app.meth));
3701 } else {
3702 meth.sym.flags_field |= ACYCLIC;
3703 }
3704 }
3705
3706 // Check for cycles in the map
3707 Symbol[] ctors = new Symbol[0];
3708 ctors = callMap.keySet().toArray(ctors);
3709 for (Symbol caller : ctors) {
3710 checkCyclicConstructor(tree, caller, callMap);
3711 }
3712 }
3713
3714 /** Look in the map to see if the given constructor is part of a
3715 * call cycle.
3716 */
3717 private void checkCyclicConstructor(JCClassDecl tree, Symbol ctor,
3718 Map<Symbol,Symbol> callMap) {
3719 if (ctor != null && (ctor.flags_field & ACYCLIC) == 0) {
3720 if ((ctor.flags_field & LOCKED) != 0) {
3721 log.error(TreeInfo.diagnosticPositionFor(ctor, tree),
3722 Errors.RecursiveCtorInvocation);
3723 } else {
3724 ctor.flags_field |= LOCKED;
3725 checkCyclicConstructor(tree, callMap.remove(ctor), callMap);
3726 ctor.flags_field &= ~LOCKED;
3727 }
3728 ctor.flags_field |= ACYCLIC;
3729 }
3730 }
3731
3732 /* *************************************************************************
3733 * Miscellaneous
3734 **************************************************************************/
3735
3736 /**
3737 * Check for division by integer constant zero
3738 * @param pos Position for error reporting.
3739 * @param operator The operator for the expression
3740 * @param operand The right hand operand for the expression
3741 */
3742 void checkDivZero(final DiagnosticPosition pos, Symbol operator, Type operand) {
3743 if (operand.constValue() != null
3744 && operand.getTag().isSubRangeOf(LONG)
3745 && ((Number) (operand.constValue())).longValue() == 0) {
3746 int opc = ((OperatorSymbol)operator).opcode;
3747 if (opc == ByteCodes.idiv || opc == ByteCodes.imod
3748 || opc == ByteCodes.ldiv || opc == ByteCodes.lmod) {
3749 deferredLintHandler.report(() -> warnDivZero(pos));
3750 }
3751 }
3752 }
3753
3754 /**
3755 * Check for possible loss of precission
3756 * @param pos Position for error reporting.
3757 * @param found The computed type of the tree
3758 * @param req The computed type of the tree
3759 */
3760 void checkLossOfPrecision(final DiagnosticPosition pos, Type found, Type req) {
3761 if (found.isNumeric() && req.isNumeric() && !types.isAssignable(found, req)) {
3762 deferredLintHandler.report(() -> {
3763 if (lint.isEnabled(LintCategory.LOSSY_CONVERSIONS))
3764 log.warning(LintCategory.LOSSY_CONVERSIONS,
3765 pos, Warnings.PossibleLossOfPrecision(found, req));
3766 });
3767 }
3768 }
3769
3770 /**
3771 * Check for empty statements after if
3772 */
3773 void checkEmptyIf(JCIf tree) {
3774 if (tree.thenpart.hasTag(SKIP) && tree.elsepart == null &&
3775 lint.isEnabled(LintCategory.EMPTY))
3776 log.warning(LintCategory.EMPTY, tree.thenpart.pos(), Warnings.EmptyIf);
3777 }
3778
3779 /** Check that symbol is unique in given scope.
3780 * @param pos Position for error reporting.
3781 * @param sym The symbol.
3782 * @param s The scope.
3783 */
3784 boolean checkUnique(DiagnosticPosition pos, Symbol sym, Scope s) {
3785 if (sym.type.isErroneous())
3786 return true;
3787 if (sym.owner.name == names.any) return false;
3788 for (Symbol byName : s.getSymbolsByName(sym.name, NON_RECURSIVE)) {
3789 if (sym != byName &&
3790 (byName.flags() & CLASH) == 0 &&
3791 sym.kind == byName.kind &&
3792 sym.name != names.error &&
3793 (sym.kind != MTH ||
3794 types.hasSameArgs(sym.type, byName.type) ||
3795 types.hasSameArgs(types.erasure(sym.type), types.erasure(byName.type)))) {
3796 if ((sym.flags() & VARARGS) != (byName.flags() & VARARGS)) {
3797 sym.flags_field |= CLASH;
3798 varargsDuplicateError(pos, sym, byName);
3799 return true;
3800 } else if (sym.kind == MTH && !types.hasSameArgs(sym.type, byName.type, false)) {
3801 duplicateErasureError(pos, sym, byName);
3802 sym.flags_field |= CLASH;
3803 return true;
3804 } else if ((sym.flags() & MATCH_BINDING) != 0 &&
3805 (byName.flags() & MATCH_BINDING) != 0 &&
3806 (byName.flags() & MATCH_BINDING_TO_OUTER) == 0) {
3807 if (!sym.type.isErroneous()) {
3808 log.error(pos, Errors.MatchBindingExists);
3809 sym.flags_field |= CLASH;
3810 }
3811 return false;
3812 } else {
3813 duplicateError(pos, byName);
3814 return false;
3815 }
3816 }
3817 }
3818 return true;
3819 }
3820
3821 /** Report duplicate declaration error.
3822 */
3823 void duplicateErasureError(DiagnosticPosition pos, Symbol sym1, Symbol sym2) {
3824 if (!sym1.type.isErroneous() && !sym2.type.isErroneous()) {
3825 log.error(pos, Errors.NameClashSameErasure(sym1, sym2));
3826 }
3827 }
3828
3829 /**Check that types imported through the ordinary imports don't clash with types imported
3830 * by other (static or ordinary) imports. Note that two static imports may import two clashing
3831 * types without an error on the imports.
3832 * @param toplevel The toplevel tree for which the test should be performed.
3833 */
3834 void checkImportsUnique(JCCompilationUnit toplevel) {
3835 WriteableScope ordinallyImportedSoFar = WriteableScope.create(toplevel.packge);
3836 WriteableScope staticallyImportedSoFar = WriteableScope.create(toplevel.packge);
3837 WriteableScope topLevelScope = toplevel.toplevelScope;
3838
3839 for (JCTree def : toplevel.defs) {
3840 if (!def.hasTag(IMPORT))
3841 continue;
3842
3843 JCImport imp = (JCImport) def;
3844
3845 if (imp.importScope == null)
3846 continue;
3847
3848 for (Symbol sym : imp.importScope.getSymbols(sym -> sym.kind == TYP)) {
3849 if (imp.isStatic()) {
3850 checkUniqueImport(imp.pos(), ordinallyImportedSoFar, staticallyImportedSoFar, topLevelScope, sym, true);
3851 staticallyImportedSoFar.enter(sym);
3852 } else {
3853 checkUniqueImport(imp.pos(), ordinallyImportedSoFar, staticallyImportedSoFar, topLevelScope, sym, false);
3854 ordinallyImportedSoFar.enter(sym);
3855 }
3856 }
3857
3858 imp.importScope = null;
3859 }
3860 }
3861
3862 /** Check that single-type import is not already imported or top-level defined,
3863 * but make an exception for two single-type imports which denote the same type.
3864 * @param pos Position for error reporting.
3865 * @param ordinallyImportedSoFar A Scope containing types imported so far through
3866 * ordinary imports.
3867 * @param staticallyImportedSoFar A Scope containing types imported so far through
3868 * static imports.
3869 * @param topLevelScope The current file's top-level Scope
3870 * @param sym The symbol.
3871 * @param staticImport Whether or not this was a static import
3872 */
3873 private boolean checkUniqueImport(DiagnosticPosition pos, Scope ordinallyImportedSoFar,
3874 Scope staticallyImportedSoFar, Scope topLevelScope,
3875 Symbol sym, boolean staticImport) {
3876 Predicate<Symbol> duplicates = candidate -> candidate != sym && !candidate.type.isErroneous();
3877 Symbol ordinaryClashing = ordinallyImportedSoFar.findFirst(sym.name, duplicates);
3878 Symbol staticClashing = null;
3879 if (ordinaryClashing == null && !staticImport) {
3880 staticClashing = staticallyImportedSoFar.findFirst(sym.name, duplicates);
3881 }
3882 if (ordinaryClashing != null || staticClashing != null) {
3883 if (ordinaryClashing != null)
3884 log.error(pos, Errors.AlreadyDefinedSingleImport(ordinaryClashing));
3885 else
3886 log.error(pos, Errors.AlreadyDefinedStaticSingleImport(staticClashing));
3887 return false;
3888 }
3889 Symbol clashing = topLevelScope.findFirst(sym.name, duplicates);
3890 if (clashing != null) {
3891 log.error(pos, Errors.AlreadyDefinedThisUnit(clashing));
3892 return false;
3893 }
3894 return true;
3895 }
3896
3897 /** Check that a qualified name is in canonical form (for import decls).
3898 */
3899 public void checkCanonical(JCTree tree) {
3900 if (!isCanonical(tree))
3901 log.error(tree.pos(),
3902 Errors.ImportRequiresCanonical(TreeInfo.symbol(tree)));
3903 }
3904 // where
3905 private boolean isCanonical(JCTree tree) {
3906 while (tree.hasTag(SELECT)) {
3907 JCFieldAccess s = (JCFieldAccess) tree;
3908 if (s.sym.owner.getQualifiedName() != TreeInfo.symbol(s.selected).getQualifiedName())
3909 return false;
3910 tree = s.selected;
3911 }
3912 return true;
3913 }
3914
3915 /** Check that an auxiliary class is not accessed from any other file than its own.
3916 */
3917 void checkForBadAuxiliaryClassAccess(DiagnosticPosition pos, Env<AttrContext> env, ClassSymbol c) {
3918 if (lint.isEnabled(Lint.LintCategory.AUXILIARYCLASS) &&
3919 (c.flags() & AUXILIARY) != 0 &&
3920 rs.isAccessible(env, c) &&
3921 !fileManager.isSameFile(c.sourcefile, env.toplevel.sourcefile))
3922 {
3923 log.warning(pos,
3924 Warnings.AuxiliaryClassAccessedFromOutsideOfItsSourceFile(c, c.sourcefile));
3925 }
3926 }
3927
3928 /**
3929 * Check for a default constructor in an exported package.
3930 */
3931 void checkDefaultConstructor(ClassSymbol c, DiagnosticPosition pos) {
3932 if (lint.isEnabled(LintCategory.MISSING_EXPLICIT_CTOR) &&
3933 ((c.flags() & (ENUM | RECORD)) == 0) &&
3934 !c.isAnonymous() &&
3935 ((c.flags() & (PUBLIC | PROTECTED)) != 0) &&
3936 Feature.MODULES.allowedInSource(source)) {
3937 NestingKind nestingKind = c.getNestingKind();
3938 switch (nestingKind) {
3939 case ANONYMOUS,
3940 LOCAL -> {return;}
3941 case TOP_LEVEL -> {;} // No additional checks needed
3942 case MEMBER -> {
3943 // For nested member classes, all the enclosing
3944 // classes must be public or protected.
3945 Symbol owner = c.owner;
3946 while (owner != null && owner.kind == TYP) {
3947 if ((owner.flags() & (PUBLIC | PROTECTED)) == 0)
3948 return;
3949 owner = owner.owner;
3950 }
3951 }
3952 }
3953
3954 // Only check classes in named packages exported by its module
3955 PackageSymbol pkg = c.packge();
3956 if (!pkg.isUnnamed()) {
3957 ModuleSymbol modle = pkg.modle;
3958 for (ExportsDirective exportDir : modle.exports) {
3959 // Report warning only if the containing
3960 // package is unconditionally exported
3961 if (exportDir.packge.equals(pkg)) {
3962 if (exportDir.modules == null || exportDir.modules.isEmpty()) {
3963 // Warning may be suppressed by
3964 // annotations; check again for being
3965 // enabled in the deferred context.
3966 deferredLintHandler.report(() -> {
3967 if (lint.isEnabled(LintCategory.MISSING_EXPLICIT_CTOR))
3968 log.warning(LintCategory.MISSING_EXPLICIT_CTOR,
3969 pos, Warnings.MissingExplicitCtor(c, pkg, modle));
3970 });
3971 } else {
3972 return;
3973 }
3974 }
3975 }
3976 }
3977 }
3978 return;
3979 }
3980
3981 private class ConversionWarner extends Warner {
3982 final String uncheckedKey;
3983 final Type found;
3984 final Type expected;
3985 public ConversionWarner(DiagnosticPosition pos, String uncheckedKey, Type found, Type expected) {
3986 super(pos);
3987 this.uncheckedKey = uncheckedKey;
3988 this.found = found;
3989 this.expected = expected;
3990 }
3991
3992 @Override
3993 public void warn(LintCategory lint) {
3994 boolean warned = this.warned;
3995 super.warn(lint);
3996 if (warned) return; // suppress redundant diagnostics
3997 switch (lint) {
3998 case UNCHECKED:
3999 Check.this.warnUnchecked(pos(), Warnings.ProbFoundReq(diags.fragment(uncheckedKey), found, expected));
4000 break;
4001 case VARARGS:
4002 if (method != null &&
4003 method.attribute(syms.trustMeType.tsym) != null &&
4004 isTrustMeAllowedOnMethod(method) &&
4005 !types.isReifiable(method.type.getParameterTypes().last())) {
4006 Check.this.warnUnsafeVararg(pos(), Warnings.VarargsUnsafeUseVarargsParam(method.params.last()));
4007 }
4008 break;
4009 default:
4010 throw new AssertionError("Unexpected lint: " + lint);
4011 }
4012 }
4013 }
4014
4015 public Warner castWarner(DiagnosticPosition pos, Type found, Type expected) {
4016 return new ConversionWarner(pos, "unchecked.cast.to.type", found, expected);
4017 }
4018
4019 public Warner convertWarner(DiagnosticPosition pos, Type found, Type expected) {
4020 return new ConversionWarner(pos, "unchecked.assign", found, expected);
4021 }
4022
4023 public void checkFunctionalInterface(JCClassDecl tree, ClassSymbol cs) {
4024 Compound functionalType = cs.attribute(syms.functionalInterfaceType.tsym);
4025
4026 if (functionalType != null) {
4027 try {
4028 types.findDescriptorSymbol((TypeSymbol)cs);
4029 } catch (Types.FunctionDescriptorLookupError ex) {
4030 DiagnosticPosition pos = tree.pos();
4031 for (JCAnnotation a : tree.getModifiers().annotations) {
4032 if (a.annotationType.type.tsym == syms.functionalInterfaceType.tsym) {
4033 pos = a.pos();
4034 break;
4035 }
4036 }
4037 log.error(pos, Errors.BadFunctionalIntfAnno1(ex.getDiagnostic()));
4038 }
4039 }
4040 }
4041
4042 public void checkImportsResolvable(final JCCompilationUnit toplevel) {
4043 for (final JCImport imp : toplevel.getImports()) {
4044 if (!imp.staticImport || !imp.qualid.hasTag(SELECT))
4045 continue;
4046 final JCFieldAccess select = (JCFieldAccess) imp.qualid;
4047 final Symbol origin;
4048 if (select.name == names.asterisk || (origin = TreeInfo.symbol(select.selected)) == null || origin.kind != TYP)
4049 continue;
4050
4051 TypeSymbol site = (TypeSymbol) TreeInfo.symbol(select.selected);
4052 if (!checkTypeContainsImportableElement(site, site, toplevel.packge, select.name, new HashSet<Symbol>())) {
4053 log.error(imp.pos(),
4054 Errors.CantResolveLocation(KindName.STATIC,
4055 select.name,
4056 null,
4057 null,
4058 Fragments.Location(kindName(site),
4059 site,
4060 null)));
4061 }
4062 }
4063 }
4064
4065 // Check that packages imported are in scope (JLS 7.4.3, 6.3, 6.5.3.1, 6.5.3.2)
4066 public void checkImportedPackagesObservable(final JCCompilationUnit toplevel) {
4067 OUTER: for (JCImport imp : toplevel.getImports()) {
4068 if (!imp.staticImport && TreeInfo.name(imp.qualid) == names.asterisk) {
4069 TypeSymbol tsym = ((JCFieldAccess)imp.qualid).selected.type.tsym;
4070 if (tsym.kind == PCK && tsym.members().isEmpty() &&
4071 !(Feature.IMPORT_ON_DEMAND_OBSERVABLE_PACKAGES.allowedInSource(source) && tsym.exists())) {
4072 log.error(DiagnosticFlag.RESOLVE_ERROR, imp.pos, Errors.DoesntExist(tsym));
4073 }
4074 }
4075 }
4076 }
4077
4078 private boolean checkTypeContainsImportableElement(TypeSymbol tsym, TypeSymbol origin, PackageSymbol packge, Name name, Set<Symbol> processed) {
4079 if (tsym == null || !processed.add(tsym))
4080 return false;
4081
4082 // also search through inherited names
4083 if (checkTypeContainsImportableElement(types.supertype(tsym.type).tsym, origin, packge, name, processed))
4084 return true;
4085
4086 for (Type t : types.interfaces(tsym.type))
4087 if (checkTypeContainsImportableElement(t.tsym, origin, packge, name, processed))
4088 return true;
4089
4090 for (Symbol sym : tsym.members().getSymbolsByName(name)) {
4091 if (sym.isStatic() &&
4092 importAccessible(sym, packge) &&
4093 sym.isMemberOf(origin, types)) {
4094 return true;
4095 }
4096 }
4097
4098 return false;
4099 }
4100
4101 // is the sym accessible everywhere in packge?
4102 public boolean importAccessible(Symbol sym, PackageSymbol packge) {
4103 try {
4104 int flags = (int)(sym.flags() & AccessFlags);
4105 switch (flags) {
4106 default:
4107 case PUBLIC:
4108 return true;
4109 case PRIVATE:
4110 return false;
4111 case 0:
4112 case PROTECTED:
4113 return sym.packge() == packge;
4114 }
4115 } catch (ClassFinder.BadClassFile err) {
4116 throw err;
4117 } catch (CompletionFailure ex) {
4118 return false;
4119 }
4120 }
4121
4122 public void checkLeaksNotAccessible(Env<AttrContext> env, JCClassDecl check) {
4123 JCCompilationUnit toplevel = env.toplevel;
4124
4125 if ( toplevel.modle == syms.unnamedModule
4126 || toplevel.modle == syms.noModule
4127 || (check.sym.flags() & COMPOUND) != 0) {
4128 return ;
4129 }
4130
4131 ExportsDirective currentExport = findExport(toplevel.packge);
4132
4133 if ( currentExport == null //not exported
4134 || currentExport.modules != null) //don't check classes in qualified export
4135 return ;
4136
4137 new TreeScanner() {
4138 Lint lint = env.info.lint;
4139 boolean inSuperType;
4140
4141 @Override
4142 public void visitBlock(JCBlock tree) {
4143 }
4144 @Override
4145 public void visitMethodDef(JCMethodDecl tree) {
4146 if (!isAPISymbol(tree.sym))
4147 return;
4148 Lint prevLint = lint;
4149 try {
4150 lint = lint.augment(tree.sym);
4151 if (lint.isEnabled(LintCategory.EXPORTS)) {
4152 super.visitMethodDef(tree);
4153 }
4154 } finally {
4155 lint = prevLint;
4156 }
4157 }
4158 @Override
4159 public void visitVarDef(JCVariableDecl tree) {
4160 if (!isAPISymbol(tree.sym) && tree.sym.owner.kind != MTH)
4161 return;
4162 Lint prevLint = lint;
4163 try {
4164 lint = lint.augment(tree.sym);
4165 if (lint.isEnabled(LintCategory.EXPORTS)) {
4166 scan(tree.mods);
4167 scan(tree.vartype);
4168 }
4169 } finally {
4170 lint = prevLint;
4171 }
4172 }
4173 @Override
4174 public void visitClassDef(JCClassDecl tree) {
4175 if (tree != check)
4176 return ;
4177
4178 if (!isAPISymbol(tree.sym))
4179 return ;
4180
4181 Lint prevLint = lint;
4182 try {
4183 lint = lint.augment(tree.sym);
4184 if (lint.isEnabled(LintCategory.EXPORTS)) {
4185 scan(tree.mods);
4186 scan(tree.typarams);
4187 try {
4188 inSuperType = true;
4189 scan(tree.extending);
4190 scan(tree.implementing);
4191 } finally {
4192 inSuperType = false;
4193 }
4194 scan(tree.defs);
4195 }
4196 } finally {
4197 lint = prevLint;
4198 }
4199 }
4200 @Override
4201 public void visitTypeApply(JCTypeApply tree) {
4202 scan(tree.clazz);
4203 boolean oldInSuperType = inSuperType;
4204 try {
4205 inSuperType = false;
4206 scan(tree.arguments);
4207 } finally {
4208 inSuperType = oldInSuperType;
4209 }
4210 }
4211 @Override
4212 public void visitIdent(JCIdent tree) {
4213 Symbol sym = TreeInfo.symbol(tree);
4214 if (sym.kind == TYP && !sym.type.hasTag(TYPEVAR)) {
4215 checkVisible(tree.pos(), sym, toplevel.packge, inSuperType);
4216 }
4217 }
4218
4219 @Override
4220 public void visitSelect(JCFieldAccess tree) {
4221 Symbol sym = TreeInfo.symbol(tree);
4222 Symbol sitesym = TreeInfo.symbol(tree.selected);
4223 if (sym.kind == TYP && sitesym.kind == PCK) {
4224 checkVisible(tree.pos(), sym, toplevel.packge, inSuperType);
4225 } else {
4226 super.visitSelect(tree);
4227 }
4228 }
4229
4230 @Override
4231 public void visitAnnotation(JCAnnotation tree) {
4232 if (tree.attribute.type.tsym.getAnnotation(java.lang.annotation.Documented.class) != null)
4233 super.visitAnnotation(tree);
4234 }
4235
4236 }.scan(check);
4237 }
4238 //where:
4239 private ExportsDirective findExport(PackageSymbol pack) {
4240 for (ExportsDirective d : pack.modle.exports) {
4241 if (d.packge == pack)
4242 return d;
4243 }
4244
4245 return null;
4246 }
4247 private boolean isAPISymbol(Symbol sym) {
4248 while (sym.kind != PCK) {
4249 if ((sym.flags() & Flags.PUBLIC) == 0 && (sym.flags() & Flags.PROTECTED) == 0) {
4250 return false;
4251 }
4252 sym = sym.owner;
4253 }
4254 return true;
4255 }
4256 private void checkVisible(DiagnosticPosition pos, Symbol what, PackageSymbol inPackage, boolean inSuperType) {
4257 if (!isAPISymbol(what) && !inSuperType) { //package private/private element
4258 log.warning(LintCategory.EXPORTS, pos, Warnings.LeaksNotAccessible(kindName(what), what, what.packge().modle));
4259 return ;
4260 }
4261
4262 PackageSymbol whatPackage = what.packge();
4263 ExportsDirective whatExport = findExport(whatPackage);
4264 ExportsDirective inExport = findExport(inPackage);
4265
4266 if (whatExport == null) { //package not exported:
4267 log.warning(LintCategory.EXPORTS, pos, Warnings.LeaksNotAccessibleUnexported(kindName(what), what, what.packge().modle));
4268 return ;
4269 }
4270
4271 if (whatExport.modules != null) {
4272 if (inExport.modules == null || !whatExport.modules.containsAll(inExport.modules)) {
4273 log.warning(LintCategory.EXPORTS, pos, Warnings.LeaksNotAccessibleUnexportedQualified(kindName(what), what, what.packge().modle));
4274 }
4275 }
4276
4277 if (whatPackage.modle != inPackage.modle && whatPackage.modle != syms.java_base) {
4278 //check that relativeTo.modle requires transitive what.modle, somehow:
4279 List<ModuleSymbol> todo = List.of(inPackage.modle);
4280
4281 while (todo.nonEmpty()) {
4282 ModuleSymbol current = todo.head;
4283 todo = todo.tail;
4284 if (current == whatPackage.modle)
4285 return ; //OK
4286 if ((current.flags() & Flags.AUTOMATIC_MODULE) != 0)
4287 continue; //for automatic modules, don't look into their dependencies
4288 for (RequiresDirective req : current.requires) {
4289 if (req.isTransitive()) {
4290 todo = todo.prepend(req.module);
4291 }
4292 }
4293 }
4294
4295 log.warning(LintCategory.EXPORTS, pos, Warnings.LeaksNotAccessibleNotRequiredTransitive(kindName(what), what, what.packge().modle));
4296 }
4297 }
4298
4299 void checkModuleExists(final DiagnosticPosition pos, ModuleSymbol msym) {
4300 if (msym.kind != MDL) {
4301 deferredLintHandler.report(() -> {
4302 if (lint.isEnabled(LintCategory.MODULE))
4303 log.warning(LintCategory.MODULE, pos, Warnings.ModuleNotFound(msym));
4304 });
4305 }
4306 }
4307
4308 void checkPackageExistsForOpens(final DiagnosticPosition pos, PackageSymbol packge) {
4309 if (packge.members().isEmpty() &&
4310 ((packge.flags() & Flags.HAS_RESOURCE) == 0)) {
4311 deferredLintHandler.report(() -> {
4312 if (lint.isEnabled(LintCategory.OPENS))
4313 log.warning(pos, Warnings.PackageEmptyOrNotFound(packge));
4314 });
4315 }
4316 }
4317
4318 void checkModuleRequires(final DiagnosticPosition pos, final RequiresDirective rd) {
4319 if ((rd.module.flags() & Flags.AUTOMATIC_MODULE) != 0) {
4320 deferredLintHandler.report(() -> {
4321 if (rd.isTransitive() && lint.isEnabled(LintCategory.REQUIRES_TRANSITIVE_AUTOMATIC)) {
4322 log.warning(pos, Warnings.RequiresTransitiveAutomatic);
4323 } else if (lint.isEnabled(LintCategory.REQUIRES_AUTOMATIC)) {
4324 log.warning(pos, Warnings.RequiresAutomatic);
4325 }
4326 });
4327 }
4328 }
4329
4330 /**
4331 * Verify the case labels conform to the constraints. Checks constraints related
4332 * combinations of patterns and other labels.
4333 *
4334 * @param cases the cases that should be checked.
4335 */
4336 void checkSwitchCaseStructure(List<JCCase> cases) {
4337 boolean wasConstant = false; // Seen a constant in the same case label
4338 boolean wasDefault = false; // Seen a default in the same case label
4339 boolean wasNullPattern = false; // Seen a null pattern in the same case label,
4340 //or fall through from a null pattern
4341 boolean wasPattern = false; // Seen a pattern in the same case label
4342 //or fall through from a pattern
4343 boolean wasTypePattern = false; // Seen a pattern in the same case label
4344 //or fall through from a type pattern
4345 boolean wasNonEmptyFallThrough = false;
4346 for (List<JCCase> l = cases; l.nonEmpty(); l = l.tail) {
4347 JCCase c = l.head;
4348 for (JCCaseLabel label : c.labels) {
4349 if (label.hasTag(CONSTANTCASELABEL)) {
4350 JCExpression expr = ((JCConstantCaseLabel) label).expr;
4351 if (TreeInfo.isNull(expr)) {
4352 if (wasPattern && !wasTypePattern && !wasNonEmptyFallThrough) {
4353 log.error(label.pos(), Errors.FlowsThroughFromPattern);
4354 }
4355 wasNullPattern = true;
4356 } else {
4357 if (wasPattern && !wasNonEmptyFallThrough) {
4358 log.error(label.pos(), Errors.FlowsThroughFromPattern);
4359 }
4360 wasConstant = true;
4361 }
4362 } else if (label.hasTag(DEFAULTCASELABEL)) {
4363 if (wasPattern && !wasNonEmptyFallThrough) {
4364 log.error(label.pos(), Errors.FlowsThroughFromPattern);
4365 }
4366 wasDefault = true;
4367 } else {
4368 JCPattern pat = ((JCPatternCaseLabel) label).pat;
4369 while (pat instanceof JCParenthesizedPattern parenthesized) {
4370 pat = parenthesized.pattern;
4371 }
4372 boolean isTypePattern = pat.hasTag(BINDINGPATTERN);
4373 if (wasPattern || wasConstant || wasDefault ||
4374 (wasNullPattern && (!isTypePattern || wasNonEmptyFallThrough))) {
4375 log.error(label.pos(), Errors.FlowsThroughToPattern);
4376 }
4377 wasPattern = true;
4378 wasTypePattern = isTypePattern;
4379 }
4380 }
4381
4382 boolean completesNormally = c.caseKind == CaseTree.CaseKind.STATEMENT ? c.completesNormally
4383 : false;
4384
4385 if (c.stats.nonEmpty()) {
4386 wasConstant = false;
4387 wasDefault = false;
4388 wasNullPattern &= completesNormally;
4389 wasPattern &= completesNormally;
4390 wasTypePattern &= completesNormally;
4391 }
4392
4393 wasNonEmptyFallThrough = c.stats.nonEmpty() && completesNormally;
4394 }
4395 }
4396
4397 void checkSwitchCaseLabelDominated(List<JCCase> cases) {
4398 List<JCCaseLabel> caseLabels = List.nil();
4399 for (List<JCCase> l = cases; l.nonEmpty(); l = l.tail) {
4400 JCCase c = l.head;
4401 for (JCCaseLabel label : c.labels) {
4402 if (label.hasTag(DEFAULTCASELABEL) || TreeInfo.isNullCaseLabel(label)) {
4403 continue;
4404 }
4405 Type currentType = labelType(label);
4406 for (JCCaseLabel testCaseLabel : caseLabels) {
4407 Type testType = labelType(testCaseLabel);
4408 if (types.isSubtype(currentType, testType) &&
4409 !currentType.hasTag(ERROR) && !testType.hasTag(ERROR)) {
4410 //the current label is potentially dominated by the existing (test) label, check:
4411 boolean dominated = false;
4412 if (label instanceof JCConstantCaseLabel) {
4413 dominated |= !(testCaseLabel instanceof JCConstantCaseLabel);
4414 } else if (label instanceof JCPatternCaseLabel patternCL &&
4415 testCaseLabel instanceof JCPatternCaseLabel testPatternCaseLabel &&
4416 TreeInfo.unguardedCaseLabel(testCaseLabel)) {
4417 dominated = patternDominated(testPatternCaseLabel.pat,
4418 patternCL.pat);
4419 }
4420 if (dominated) {
4421 log.error(label.pos(), Errors.PatternDominated);
4422 }
4423 }
4424 }
4425 caseLabels = caseLabels.prepend(label);
4426 }
4427 }
4428 }
4429 //where:
4430 private Type labelType(JCCaseLabel label) {
4431 return types.erasure(switch (label.getTag()) {
4432 case PATTERNCASELABEL -> ((JCPatternCaseLabel) label).pat.type;
4433 case CONSTANTCASELABEL -> types.boxedTypeOrType(((JCConstantCaseLabel) label).expr.type);
4434 default -> throw Assert.error("Unexpected tree kind: " + label.getTag());
4435 });
4436 }
4437 private boolean patternDominated(JCPattern existingPattern, JCPattern currentPattern) {
4438 Type existingPatternType = types.erasure(existingPattern.type);
4439 Type currentPatternType = types.erasure(currentPattern.type);
4440 if (existingPatternType.isPrimitive() ^ currentPatternType.isPrimitive()) {
4441 return false;
4442 }
4443 if (existingPatternType.isPrimitive()) {
4444 return types.isSameType(existingPatternType, currentPatternType);
4445 } else {
4446 if (!types.isSubtype(currentPatternType, existingPatternType)) {
4447 return false;
4448 }
4449 }
4450 while (existingPattern instanceof JCParenthesizedPattern parenthesized) {
4451 existingPattern = parenthesized.pattern;
4452 }
4453 while (currentPattern instanceof JCParenthesizedPattern parenthesized) {
4454 currentPattern = parenthesized.pattern;
4455 }
4456 if (currentPattern instanceof JCBindingPattern) {
4457 return existingPattern instanceof JCBindingPattern;
4458 } else if (currentPattern instanceof JCRecordPattern currentRecordPattern) {
4459 if (existingPattern instanceof JCBindingPattern) {
4460 return true;
4461 } else if (existingPattern instanceof JCRecordPattern existingRecordPattern) {
4462 List<JCPattern> existingNested = existingRecordPattern.nested;
4463 List<JCPattern> currentNested = currentRecordPattern.nested;
4464 if (existingNested.size() != currentNested.size()) {
4465 return false;
4466 }
4467 while (existingNested.nonEmpty()) {
4468 if (!patternDominated(existingNested.head, currentNested.head)) {
4469 return false;
4470 }
4471 existingNested = existingNested.tail;
4472 currentNested = currentNested.tail;
4473 }
4474 return true;
4475 } else {
4476 Assert.error("Unknown pattern: " + existingPattern.getTag());
4477 }
4478 } else {
4479 Assert.error("Unknown pattern: " + currentPattern.getTag());
4480 }
4481 return false;
4482 }
4483
4484 /** check if a type is a subtype of Externalizable, if that is available. */
4485 boolean isExternalizable(Type t) {
4486 try {
4487 syms.externalizableType.complete();
4488 }
4489 catch (CompletionFailure e) {
4490 return false;
4491 }
4492 return types.isSubtype(t, syms.externalizableType);
4493 }
4494
4495 /**
4496 * Check structure of serialization declarations.
4497 */
4498 public void checkSerialStructure(JCClassDecl tree, ClassSymbol c) {
4499 (new SerialTypeVisitor()).visit(c, tree);
4500 }
4501
4502 /**
4503 * This visitor will warn if a serialization-related field or
4504 * method is declared in a suspicious or incorrect way. In
4505 * particular, it will warn for cases where the runtime
4506 * serialization mechanism will silently ignore a mis-declared
4507 * entity.
4508 *
4509 * Distinguished serialization-related fields and methods:
4510 *
4511 * Methods:
4512 *
4513 * private void writeObject(ObjectOutputStream stream) throws IOException
4514 * ANY-ACCESS-MODIFIER Object writeReplace() throws ObjectStreamException
4515 *
4516 * private void readObject(ObjectInputStream stream) throws IOException, ClassNotFoundException
4517 * private void readObjectNoData() throws ObjectStreamException
4518 * ANY-ACCESS-MODIFIER Object readResolve() throws ObjectStreamException
4519 *
4520 * Fields:
4521 *
4522 * private static final long serialVersionUID
4523 * private static final ObjectStreamField[] serialPersistentFields
4524 *
4525 * Externalizable: methods defined on the interface
4526 * public void writeExternal(ObjectOutput) throws IOException
4527 * public void readExternal(ObjectInput) throws IOException
4528 */
4529 private class SerialTypeVisitor extends ElementKindVisitor14<Void, JCClassDecl> {
4530 SerialTypeVisitor() {
4531 this.lint = Check.this.lint;
4532 }
4533
4534 private static final Set<String> serialMethodNames =
4535 Set.of("writeObject", "writeReplace",
4536 "readObject", "readObjectNoData",
4537 "readResolve");
4538
4539 private static final Set<String> serialFieldNames =
4540 Set.of("serialVersionUID", "serialPersistentFields");
4541
4542 // Type of serialPersistentFields
4543 private final Type OSF_TYPE = new Type.ArrayType(syms.objectStreamFieldType, syms.arrayClass);
4544
4545 Lint lint;
4546
4547 @Override
4548 public Void defaultAction(Element e, JCClassDecl p) {
4549 throw new IllegalArgumentException(Objects.requireNonNullElse(e.toString(), ""));
4550 }
4551
4552 @Override
4553 public Void visitType(TypeElement e, JCClassDecl p) {
4554 runUnderLint(e, p, (symbol, param) -> super.visitType(symbol, param));
4555 return null;
4556 }
4557
4558 @Override
4559 public Void visitTypeAsClass(TypeElement e,
4560 JCClassDecl p) {
4561 // Anonymous classes filtered out by caller.
4562
4563 ClassSymbol c = (ClassSymbol)e;
4564
4565 checkCtorAccess(p, c);
4566
4567 // Check for missing serialVersionUID; check *not* done
4568 // for enums or records.
4569 VarSymbol svuidSym = null;
4570 for (Symbol sym : c.members().getSymbolsByName(names.serialVersionUID)) {
4571 if (sym.kind == VAR) {
4572 svuidSym = (VarSymbol)sym;
4573 break;
4574 }
4575 }
4576
4577 if (svuidSym == null) {
4578 log.warning(LintCategory.SERIAL, p.pos(), Warnings.MissingSVUID(c));
4579 }
4580
4581 // Check for serialPersistentFields to gate checks for
4582 // non-serializable non-transient instance fields
4583 boolean serialPersistentFieldsPresent =
4584 c.members()
4585 .getSymbolsByName(names.serialPersistentFields, sym -> sym.kind == VAR)
4586 .iterator()
4587 .hasNext();
4588
4589 // Check declarations of serialization-related methods and
4590 // fields
4591 for(Symbol el : c.getEnclosedElements()) {
4592 runUnderLint(el, p, (enclosed, tree) -> {
4593 String name = null;
4594 switch(enclosed.getKind()) {
4595 case FIELD -> {
4596 if (!serialPersistentFieldsPresent) {
4597 var flags = enclosed.flags();
4598 if ( ((flags & TRANSIENT) == 0) &&
4599 ((flags & STATIC) == 0)) {
4600 Type varType = enclosed.asType();
4601 if (!canBeSerialized(varType)) {
4602 // Note per JLS arrays are
4603 // serializable even if the
4604 // component type is not.
4605 log.warning(LintCategory.SERIAL,
4606 TreeInfo.diagnosticPositionFor(enclosed, tree),
4607 Warnings.NonSerializableInstanceField);
4608 } else if (varType.hasTag(ARRAY)) {
4609 ArrayType arrayType = (ArrayType)varType;
4610 Type elementType = arrayType.elemtype;
4611 while (elementType.hasTag(ARRAY)) {
4612 arrayType = (ArrayType)elementType;
4613 elementType = arrayType.elemtype;
4614 }
4615 if (!canBeSerialized(elementType)) {
4616 log.warning(LintCategory.SERIAL,
4617 TreeInfo.diagnosticPositionFor(enclosed, tree),
4618 Warnings.NonSerializableInstanceFieldArray(elementType));
4619 }
4620 }
4621 }
4622 }
4623
4624 name = enclosed.getSimpleName().toString();
4625 if (serialFieldNames.contains(name)) {
4626 VarSymbol field = (VarSymbol)enclosed;
4627 switch (name) {
4628 case "serialVersionUID" -> checkSerialVersionUID(tree, e, field);
4629 case "serialPersistentFields" -> checkSerialPersistentFields(tree, e, field);
4630 default -> throw new AssertionError();
4631 }
4632 }
4633 }
4634
4635 // Correctly checking the serialization-related
4636 // methods is subtle. For the methods declared to be
4637 // private or directly declared in the class, the
4638 // enclosed elements of the class can be checked in
4639 // turn. However, writeReplace and readResolve can be
4640 // declared in a superclass and inherited. Note that
4641 // the runtime lookup walks the superclass chain
4642 // looking for writeReplace/readResolve via
4643 // Class.getDeclaredMethod. This differs from calling
4644 // Elements.getAllMembers(TypeElement) as the latter
4645 // will also pull in default methods from
4646 // superinterfaces. In other words, the runtime checks
4647 // (which long predate default methods on interfaces)
4648 // do not admit the possibility of inheriting methods
4649 // this way, a difference from general inheritance.
4650
4651 // The current implementation just checks the enclosed
4652 // elements and does not directly check the inherited
4653 // methods. If all the types are being checked this is
4654 // less of a concern; however, there are cases that
4655 // could be missed. In particular, readResolve and
4656 // writeReplace could, in principle, by inherited from
4657 // a non-serializable superclass and thus not checked
4658 // even if compiled with a serializable child class.
4659 case METHOD -> {
4660 var method = (MethodSymbol)enclosed;
4661 name = method.getSimpleName().toString();
4662 if (serialMethodNames.contains(name)) {
4663 switch (name) {
4664 case "writeObject" -> checkWriteObject(tree, e, method);
4665 case "writeReplace" -> checkWriteReplace(tree,e, method);
4666 case "readObject" -> checkReadObject(tree,e, method);
4667 case "readObjectNoData" -> checkReadObjectNoData(tree, e, method);
4668 case "readResolve" -> checkReadResolve(tree, e, method);
4669 default -> throw new AssertionError();
4670 }
4671 }
4672 }
4673 }
4674 });
4675 }
4676
4677 return null;
4678 }
4679
4680 boolean canBeSerialized(Type type) {
4681 return type.isPrimitive() || rs.isSerializable(type);
4682 }
4683
4684 /**
4685 * Check that Externalizable class needs a public no-arg
4686 * constructor.
4687 *
4688 * Check that a Serializable class has access to the no-arg
4689 * constructor of its first nonserializable superclass.
4690 */
4691 private void checkCtorAccess(JCClassDecl tree, ClassSymbol c) {
4692 if (isExternalizable(c.type)) {
4693 for(var sym : c.getEnclosedElements()) {
4694 if (sym.isConstructor() &&
4695 ((sym.flags() & PUBLIC) == PUBLIC)) {
4696 if (((MethodSymbol)sym).getParameters().isEmpty()) {
4697 return;
4698 }
4699 }
4700 }
4701 log.warning(LintCategory.SERIAL, tree.pos(),
4702 Warnings.ExternalizableMissingPublicNoArgCtor);
4703 } else {
4704 // Approximate access to the no-arg constructor up in
4705 // the superclass chain by checking that the
4706 // constructor is not private. This may not handle
4707 // some cross-package situations correctly.
4708 Type superClass = c.getSuperclass();
4709 // java.lang.Object is *not* Serializable so this loop
4710 // should terminate.
4711 while (rs.isSerializable(superClass) ) {
4712 try {
4713 superClass = (Type)((TypeElement)(((DeclaredType)superClass)).asElement()).getSuperclass();
4714 } catch(ClassCastException cce) {
4715 return ; // Don't try to recover
4716 }
4717 }
4718 // Non-Serializable superclass
4719 try {
4720 ClassSymbol supertype = ((ClassSymbol)(((DeclaredType)superClass).asElement()));
4721 for(var sym : supertype.getEnclosedElements()) {
4722 if (sym.isConstructor()) {
4723 MethodSymbol ctor = (MethodSymbol)sym;
4724 if (ctor.getParameters().isEmpty()) {
4725 if (((ctor.flags() & PRIVATE) == PRIVATE) ||
4726 // Handle nested classes and implicit this$0
4727 (supertype.getNestingKind() == NestingKind.MEMBER &&
4728 ((supertype.flags() & STATIC) == 0)))
4729 log.warning(LintCategory.SERIAL, tree.pos(),
4730 Warnings.SerializableMissingAccessNoArgCtor(supertype.getQualifiedName()));
4731 }
4732 }
4733 }
4734 } catch (ClassCastException cce) {
4735 return ; // Don't try to recover
4736 }
4737 return;
4738 }
4739 }
4740
4741 private void checkSerialVersionUID(JCClassDecl tree, Element e, VarSymbol svuid) {
4742 // To be effective, serialVersionUID must be marked static
4743 // and final, but private is recommended. But alas, in
4744 // practice there are many non-private serialVersionUID
4745 // fields.
4746 if ((svuid.flags() & (STATIC | FINAL)) !=
4747 (STATIC | FINAL)) {
4748 log.warning(LintCategory.SERIAL,
4749 TreeInfo.diagnosticPositionFor(svuid, tree),
4750 Warnings.ImproperSVUID((Symbol)e));
4751 }
4752
4753 // check svuid has type long
4754 if (!svuid.type.hasTag(LONG)) {
4755 log.warning(LintCategory.SERIAL,
4756 TreeInfo.diagnosticPositionFor(svuid, tree),
4757 Warnings.LongSVUID((Symbol)e));
4758 }
4759
4760 if (svuid.getConstValue() == null)
4761 log.warning(LintCategory.SERIAL,
4762 TreeInfo.diagnosticPositionFor(svuid, tree),
4763 Warnings.ConstantSVUID((Symbol)e));
4764 }
4765
4766 private void checkSerialPersistentFields(JCClassDecl tree, Element e, VarSymbol spf) {
4767 // To be effective, serialPersisentFields must be private, static, and final.
4768 if ((spf.flags() & (PRIVATE | STATIC | FINAL)) !=
4769 (PRIVATE | STATIC | FINAL)) {
4770 log.warning(LintCategory.SERIAL,
4771 TreeInfo.diagnosticPositionFor(spf, tree), Warnings.ImproperSPF);
4772 }
4773
4774 if (!types.isSameType(spf.type, OSF_TYPE)) {
4775 log.warning(LintCategory.SERIAL,
4776 TreeInfo.diagnosticPositionFor(spf, tree), Warnings.OSFArraySPF);
4777 }
4778
4779 if (isExternalizable((Type)(e.asType()))) {
4780 log.warning(LintCategory.SERIAL, tree.pos(),
4781 Warnings.IneffectualSerialFieldExternalizable);
4782 }
4783
4784 // Warn if serialPersistentFields is initialized to a
4785 // literal null.
4786 JCTree spfDecl = TreeInfo.declarationFor(spf, tree);
4787 if (spfDecl != null && spfDecl.getTag() == VARDEF) {
4788 JCVariableDecl variableDef = (JCVariableDecl) spfDecl;
4789 JCExpression initExpr = variableDef.init;
4790 if (initExpr != null && TreeInfo.isNull(initExpr)) {
4791 log.warning(LintCategory.SERIAL, initExpr.pos(),
4792 Warnings.SPFNullInit);
4793 }
4794 }
4795 }
4796
4797 private void checkWriteObject(JCClassDecl tree, Element e, MethodSymbol method) {
4798 // The "synchronized" modifier is seen in the wild on
4799 // readObject and writeObject methods and is generally
4800 // innocuous.
4801
4802 // private void writeObject(ObjectOutputStream stream) throws IOException
4803 checkPrivateNonStaticMethod(tree, method);
4804 checkReturnType(tree, e, method, syms.voidType);
4805 checkOneArg(tree, e, method, syms.objectOutputStreamType);
4806 checkExceptions(tree, e, method, syms.ioExceptionType);
4807 checkExternalizable(tree, e, method);
4808 }
4809
4810 private void checkWriteReplace(JCClassDecl tree, Element e, MethodSymbol method) {
4811 // ANY-ACCESS-MODIFIER Object writeReplace() throws
4812 // ObjectStreamException
4813
4814 // Excluding abstract, could have a more complicated
4815 // rule based on abstract-ness of the class
4816 checkConcreteInstanceMethod(tree, e, method);
4817 checkReturnType(tree, e, method, syms.objectType);
4818 checkNoArgs(tree, e, method);
4819 checkExceptions(tree, e, method, syms.objectStreamExceptionType);
4820 }
4821
4822 private void checkReadObject(JCClassDecl tree, Element e, MethodSymbol method) {
4823 // The "synchronized" modifier is seen in the wild on
4824 // readObject and writeObject methods and is generally
4825 // innocuous.
4826
4827 // private void readObject(ObjectInputStream stream)
4828 // throws IOException, ClassNotFoundException
4829 checkPrivateNonStaticMethod(tree, method);
4830 checkReturnType(tree, e, method, syms.voidType);
4831 checkOneArg(tree, e, method, syms.objectInputStreamType);
4832 checkExceptions(tree, e, method, syms.ioExceptionType, syms.classNotFoundExceptionType);
4833 checkExternalizable(tree, e, method);
4834 }
4835
4836 private void checkReadObjectNoData(JCClassDecl tree, Element e, MethodSymbol method) {
4837 // private void readObjectNoData() throws ObjectStreamException
4838 checkPrivateNonStaticMethod(tree, method);
4839 checkReturnType(tree, e, method, syms.voidType);
4840 checkNoArgs(tree, e, method);
4841 checkExceptions(tree, e, method, syms.objectStreamExceptionType);
4842 checkExternalizable(tree, e, method);
4843 }
4844
4845 private void checkReadResolve(JCClassDecl tree, Element e, MethodSymbol method) {
4846 // ANY-ACCESS-MODIFIER Object readResolve()
4847 // throws ObjectStreamException
4848
4849 // Excluding abstract, could have a more complicated
4850 // rule based on abstract-ness of the class
4851 checkConcreteInstanceMethod(tree, e, method);
4852 checkReturnType(tree,e, method, syms.objectType);
4853 checkNoArgs(tree, e, method);
4854 checkExceptions(tree, e, method, syms.objectStreamExceptionType);
4855 }
4856
4857 void checkPrivateNonStaticMethod(JCClassDecl tree, MethodSymbol method) {
4858 var flags = method.flags();
4859 if ((flags & PRIVATE) == 0) {
4860 log.warning(LintCategory.SERIAL,
4861 TreeInfo.diagnosticPositionFor(method, tree),
4862 Warnings.SerialMethodNotPrivate(method.getSimpleName()));
4863 }
4864
4865 if ((flags & STATIC) != 0) {
4866 log.warning(LintCategory.SERIAL,
4867 TreeInfo.diagnosticPositionFor(method, tree),
4868 Warnings.SerialMethodStatic(method.getSimpleName()));
4869 }
4870 }
4871
4872 /**
4873 * Per section 1.12 "Serialization of Enum Constants" of
4874 * the serialization specification, due to the special
4875 * serialization handling of enums, any writeObject,
4876 * readObject, writeReplace, and readResolve methods are
4877 * ignored as are serialPersistentFields and
4878 * serialVersionUID fields.
4879 */
4880 @Override
4881 public Void visitTypeAsEnum(TypeElement e,
4882 JCClassDecl p) {
4883 for(Element el : e.getEnclosedElements()) {
4884 runUnderLint(el, p, (enclosed, tree) -> {
4885 String name = enclosed.getSimpleName().toString();
4886 switch(enclosed.getKind()) {
4887 case FIELD -> {
4888 if (serialFieldNames.contains(name)) {
4889 log.warning(LintCategory.SERIAL, tree.pos(),
4890 Warnings.IneffectualSerialFieldEnum(name));
4891 }
4892 }
4893
4894 case METHOD -> {
4895 if (serialMethodNames.contains(name)) {
4896 log.warning(LintCategory.SERIAL, tree.pos(),
4897 Warnings.IneffectualSerialMethodEnum(name));
4898 }
4899 }
4900 }
4901 });
4902 }
4903 return null;
4904 }
4905
4906 /**
4907 * Most serialization-related fields and methods on interfaces
4908 * are ineffectual or problematic.
4909 */
4910 @Override
4911 public Void visitTypeAsInterface(TypeElement e,
4912 JCClassDecl p) {
4913 for(Element el : e.getEnclosedElements()) {
4914 runUnderLint(el, p, (enclosed, tree) -> {
4915 String name = null;
4916 switch(enclosed.getKind()) {
4917 case FIELD -> {
4918 var field = (VarSymbol)enclosed;
4919 name = field.getSimpleName().toString();
4920 switch(name) {
4921 case "serialPersistentFields" -> {
4922 log.warning(LintCategory.SERIAL,
4923 TreeInfo.diagnosticPositionFor(field, tree),
4924 Warnings.IneffectualSerialFieldInterface);
4925 }
4926
4927 case "serialVersionUID" -> {
4928 checkSerialVersionUID(tree, e, field);
4929 }
4930 }
4931 }
4932
4933 case METHOD -> {
4934 var method = (MethodSymbol)enclosed;
4935 name = enclosed.getSimpleName().toString();
4936 if (serialMethodNames.contains(name)) {
4937 switch (name) {
4938 case
4939 "readObject",
4940 "readObjectNoData",
4941 "writeObject" -> checkPrivateMethod(tree, e, method);
4942
4943 case
4944 "writeReplace",
4945 "readResolve" -> checkDefaultIneffective(tree, e, method);
4946
4947 default -> throw new AssertionError();
4948 }
4949
4950 }
4951 }
4952 }
4953 });
4954 }
4955
4956 return null;
4957 }
4958
4959 private void checkPrivateMethod(JCClassDecl tree,
4960 Element e,
4961 MethodSymbol method) {
4962 if ((method.flags() & PRIVATE) == 0) {
4963 log.warning(LintCategory.SERIAL,
4964 TreeInfo.diagnosticPositionFor(method, tree),
4965 Warnings.NonPrivateMethodWeakerAccess);
4966 }
4967 }
4968
4969 private void checkDefaultIneffective(JCClassDecl tree,
4970 Element e,
4971 MethodSymbol method) {
4972 if ((method.flags() & DEFAULT) == DEFAULT) {
4973 log.warning(LintCategory.SERIAL,
4974 TreeInfo.diagnosticPositionFor(method, tree),
4975 Warnings.DefaultIneffective);
4976
4977 }
4978 }
4979
4980 @Override
4981 public Void visitTypeAsAnnotationType(TypeElement e,
4982 JCClassDecl p) {
4983 // Per the JLS, annotation types are not serializeable
4984 return null;
4985 }
4986
4987 /**
4988 * From the Java Object Serialization Specification, 1.13
4989 * Serialization of Records:
4990 *
4991 * "The process by which record objects are serialized or
4992 * externalized cannot be customized; any class-specific
4993 * writeObject, readObject, readObjectNoData, writeExternal,
4994 * and readExternal methods defined by record classes are
4995 * ignored during serialization and deserialization. However,
4996 * a substitute object to be serialized or a designate
4997 * replacement may be specified, by the writeReplace and
4998 * readResolve methods, respectively. Any
4999 * serialPersistentFields field declaration is
5000 * ignored. Documenting serializable fields and data for
5001 * record classes is unnecessary, since there is no variation
5002 * in the serial form, other than whether a substitute or
5003 * replacement object is used. The serialVersionUID of a
5004 * record class is 0L unless explicitly declared. The
5005 * requirement for matching serialVersionUID values is waived
5006 * for record classes."
5007 */
5008 @Override
5009 public Void visitTypeAsRecord(TypeElement e,
5010 JCClassDecl p) {
5011 for(Element el : e.getEnclosedElements()) {
5012 runUnderLint(el, p, (enclosed, tree) -> {
5013 String name = enclosed.getSimpleName().toString();
5014 switch(enclosed.getKind()) {
5015 case FIELD -> {
5016 switch(name) {
5017 case "serialPersistentFields" -> {
5018 log.warning(LintCategory.SERIAL, tree.pos(),
5019 Warnings.IneffectualSerialFieldRecord);
5020 }
5021
5022 case "serialVersionUID" -> {
5023 // Could generate additional warning that
5024 // svuid value is not checked to match for
5025 // records.
5026 checkSerialVersionUID(tree, e, (VarSymbol)enclosed);
5027 }
5028
5029 }
5030 }
5031
5032 case METHOD -> {
5033 var method = (MethodSymbol)enclosed;
5034 switch(name) {
5035 case "writeReplace" -> checkWriteReplace(tree, e, method);
5036 case "readResolve" -> checkReadResolve(tree, e, method);
5037 default -> {
5038 if (serialMethodNames.contains(name)) {
5039 log.warning(LintCategory.SERIAL, tree.pos(),
5040 Warnings.IneffectualSerialMethodRecord(name));
5041 }
5042 }
5043 }
5044
5045 }
5046 }
5047 });
5048 }
5049 return null;
5050 }
5051
5052 void checkConcreteInstanceMethod(JCClassDecl tree,
5053 Element enclosing,
5054 MethodSymbol method) {
5055 if ((method.flags() & (STATIC | ABSTRACT)) != 0) {
5056 log.warning(LintCategory.SERIAL,
5057 TreeInfo.diagnosticPositionFor(method, tree),
5058 Warnings.SerialConcreteInstanceMethod(method.getSimpleName()));
5059 }
5060 }
5061
5062 private void checkReturnType(JCClassDecl tree,
5063 Element enclosing,
5064 MethodSymbol method,
5065 Type expectedReturnType) {
5066 // Note: there may be complications checking writeReplace
5067 // and readResolve since they return Object and could, in
5068 // principle, have covariant overrides and any synthetic
5069 // bridge method would not be represented here for
5070 // checking.
5071 Type rtype = method.getReturnType();
5072 if (!types.isSameType(expectedReturnType, rtype)) {
5073 log.warning(LintCategory.SERIAL,
5074 TreeInfo.diagnosticPositionFor(method, tree),
5075 Warnings.SerialMethodUnexpectedReturnType(method.getSimpleName(),
5076 rtype, expectedReturnType));
5077 }
5078 }
5079
5080 private void checkOneArg(JCClassDecl tree,
5081 Element enclosing,
5082 MethodSymbol method,
5083 Type expectedType) {
5084 String name = method.getSimpleName().toString();
5085
5086 var parameters= method.getParameters();
5087
5088 if (parameters.size() != 1) {
5089 log.warning(LintCategory.SERIAL,
5090 TreeInfo.diagnosticPositionFor(method, tree),
5091 Warnings.SerialMethodOneArg(method.getSimpleName(), parameters.size()));
5092 return;
5093 }
5094
5095 Type parameterType = parameters.get(0).asType();
5096 if (!types.isSameType(parameterType, expectedType)) {
5097 log.warning(LintCategory.SERIAL,
5098 TreeInfo.diagnosticPositionFor(method, tree),
5099 Warnings.SerialMethodParameterType(method.getSimpleName(),
5100 expectedType,
5101 parameterType));
5102 }
5103 }
5104
5105 private void checkNoArgs(JCClassDecl tree, Element enclosing, MethodSymbol method) {
5106 var parameters = method.getParameters();
5107 if (!parameters.isEmpty()) {
5108 log.warning(LintCategory.SERIAL,
5109 TreeInfo.diagnosticPositionFor(parameters.get(0), tree),
5110 Warnings.SerialMethodNoArgs(method.getSimpleName()));
5111 }
5112 }
5113
5114 private void checkExternalizable(JCClassDecl tree, Element enclosing, MethodSymbol method) {
5115 // If the enclosing class is externalizable, warn for the method
5116 if (isExternalizable((Type)enclosing.asType())) {
5117 log.warning(LintCategory.SERIAL, tree.pos(),
5118 Warnings.IneffectualSerialMethodExternalizable(method.getSimpleName()));
5119 }
5120 return;
5121 }
5122
5123 private void checkExceptions(JCClassDecl tree,
5124 Element enclosing,
5125 MethodSymbol method,
5126 Type... declaredExceptions) {
5127 for (Type thrownType: method.getThrownTypes()) {
5128 // For each exception in the throws clause of the
5129 // method, if not an Error and not a RuntimeException,
5130 // check if the exception is a subtype of a declared
5131 // exception from the throws clause of the
5132 // serialization method in question.
5133 if (types.isSubtype(thrownType, syms.runtimeExceptionType) ||
5134 types.isSubtype(thrownType, syms.errorType) ) {
5135 continue;
5136 } else {
5137 boolean declared = false;
5138 for (Type declaredException : declaredExceptions) {
5139 if (types.isSubtype(thrownType, declaredException)) {
5140 declared = true;
5141 continue;
5142 }
5143 }
5144 if (!declared) {
5145 log.warning(LintCategory.SERIAL,
5146 TreeInfo.diagnosticPositionFor(method, tree),
5147 Warnings.SerialMethodUnexpectedException(method.getSimpleName(),
5148 thrownType));
5149 }
5150 }
5151 }
5152 return;
5153 }
5154
5155 private <E extends Element> Void runUnderLint(E symbol, JCClassDecl p, BiConsumer<E, JCClassDecl> task) {
5156 Lint prevLint = lint;
5157 try {
5158 lint = lint.augment((Symbol) symbol);
5159
5160 if (lint.isEnabled(LintCategory.SERIAL)) {
5161 task.accept(symbol, p);
5162 }
5163
5164 return null;
5165 } finally {
5166 lint = prevLint;
5167 }
5168 }
5169
5170 }
5171
5172 }