1 | /* |
2 | * Copyright 1999-2006 Sun Microsystems, Inc. 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. Sun designates this |
8 | * particular file as subject to the "Classpath" exception as provided |
9 | * by Sun 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 Sun Microsystems, Inc., 4150 Network Circle, Santa Clara, |
22 | * CA 95054 USA or visit www.sun.com if you need additional information or |
23 | * have any questions. |
24 | */ |
25 | |
26 | package com.sun.tools.javac.comp; |
27 | |
28 | import java.util.*; |
29 | import java.util.Set; |
30 | |
31 | import com.sun.tools.javac.code.*; |
32 | import com.sun.tools.javac.jvm.*; |
33 | import com.sun.tools.javac.tree.*; |
34 | import com.sun.tools.javac.util.*; |
35 | import com.sun.tools.javac.util.JCDiagnostic.DiagnosticPosition; |
36 | import com.sun.tools.javac.util.List; |
37 | |
38 | import com.sun.tools.javac.tree.JCTree.*; |
39 | import com.sun.tools.javac.code.Lint; |
40 | import com.sun.tools.javac.code.Lint.LintCategory; |
41 | import com.sun.tools.javac.code.Type.*; |
42 | import com.sun.tools.javac.code.Symbol.*; |
43 | |
44 | import static com.sun.tools.javac.code.Flags.*; |
45 | import static com.sun.tools.javac.code.Kinds.*; |
46 | import static com.sun.tools.javac.code.TypeTags.*; |
47 | |
48 | /** Type checking helper class for the attribution phase. |
49 | * |
50 | * <p><b>This is NOT part of any API supported by Sun Microsystems. If |
51 | * you write code that depends on this, you do so at your own risk. |
52 | * This code and its internal interfaces are subject to change or |
53 | * deletion without notice.</b> |
54 | */ |
55 | public class Check { |
56 | protected static final Context.Key<Check> checkKey = |
57 | new Context.Key<Check>(); |
58 | |
59 | private final Name.Table names; |
60 | private final Log log; |
61 | private final Symtab syms; |
62 | private final Infer infer; |
63 | private final Target target; |
64 | private final Source source; |
65 | private final Types types; |
66 | private final boolean skipAnnotations; |
67 | private final TreeInfo treeinfo; |
68 | |
69 | // The set of lint options currently in effect. It is initialized |
70 | // from the context, and then is set/reset as needed by Attr as it |
71 | // visits all the various parts of the trees during attribution. |
72 | private Lint lint; |
73 | |
74 | public static Check instance(Context context) { |
75 | Check instance = context.get(checkKey); |
76 | if (instance == null) |
77 | instance = new Check(context); |
78 | return instance; |
79 | } |
80 | |
81 | protected Check(Context context) { |
82 | context.put(checkKey, this); |
83 | |
84 | names = Name.Table.instance(context); |
85 | log = Log.instance(context); |
86 | syms = Symtab.instance(context); |
87 | infer = Infer.instance(context); |
88 | this.types = Types.instance(context); |
89 | Options options = Options.instance(context); |
90 | target = Target.instance(context); |
91 | source = Source.instance(context); |
92 | lint = Lint.instance(context); |
93 | treeinfo = TreeInfo.instance(context); |
94 | |
95 | Source source = Source.instance(context); |
96 | allowGenerics = source.allowGenerics(); |
97 | allowAnnotations = source.allowAnnotations(); |
98 | complexInference = options.get("-complexinference") != null; |
99 | skipAnnotations = options.get("skipAnnotations") != null; |
100 | |
101 | boolean verboseDeprecated = lint.isEnabled(LintCategory.DEPRECATION); |
102 | boolean verboseUnchecked = lint.isEnabled(LintCategory.UNCHECKED); |
103 | |
104 | deprecationHandler = new MandatoryWarningHandler(log,verboseDeprecated, "deprecated"); |
105 | uncheckedHandler = new MandatoryWarningHandler(log, verboseUnchecked, "unchecked"); |
106 | } |
107 | |
108 | /** Switch: generics enabled? |
109 | */ |
110 | boolean allowGenerics; |
111 | |
112 | /** Switch: annotations enabled? |
113 | */ |
114 | boolean allowAnnotations; |
115 | |
116 | /** Switch: -complexinference option set? |
117 | */ |
118 | boolean complexInference; |
119 | |
120 | /** A table mapping flat names of all compiled classes in this run to their |
121 | * symbols; maintained from outside. |
122 | */ |
123 | public Map<Name,ClassSymbol> compiled = new HashMap<Name, ClassSymbol>(); |
124 | |
125 | /** A handler for messages about deprecated usage. |
126 | */ |
127 | private MandatoryWarningHandler deprecationHandler; |
128 | |
129 | /** A handler for messages about unchecked or unsafe usage. |
130 | */ |
131 | private MandatoryWarningHandler uncheckedHandler; |
132 | |
133 | |
134 | /* ************************************************************************* |
135 | * Errors and Warnings |
136 | **************************************************************************/ |
137 | |
138 | Lint setLint(Lint newLint) { |
139 | Lint prev = lint; |
140 | lint = newLint; |
141 | return prev; |
142 | } |
143 | |
144 | /** Warn about deprecated symbol. |
145 | * @param pos Position to be used for error reporting. |
146 | * @param sym The deprecated symbol. |
147 | */ |
148 | void warnDeprecated(DiagnosticPosition pos, Symbol sym) { |
149 | if (!lint.isSuppressed(LintCategory.DEPRECATION)) |
150 | deprecationHandler.report(pos, "has.been.deprecated", sym, sym.location()); |
151 | } |
152 | |
153 | /** Warn about unchecked operation. |
154 | * @param pos Position to be used for error reporting. |
155 | * @param msg A string describing the problem. |
156 | */ |
157 | public void warnUnchecked(DiagnosticPosition pos, String msg, Object... args) { |
158 | if (!lint.isSuppressed(LintCategory.UNCHECKED)) |
159 | uncheckedHandler.report(pos, msg, args); |
160 | } |
161 | |
162 | /** |
163 | * Report any deferred diagnostics. |
164 | */ |
165 | public void reportDeferredDiagnostics() { |
166 | deprecationHandler.reportDeferredDiagnostic(); |
167 | uncheckedHandler.reportDeferredDiagnostic(); |
168 | } |
169 | |
170 | |
171 | /** Report a failure to complete a class. |
172 | * @param pos Position to be used for error reporting. |
173 | * @param ex The failure to report. |
174 | */ |
175 | public Type completionError(DiagnosticPosition pos, CompletionFailure ex) { |
176 | log.error(pos, "cant.access", ex.sym, ex.errmsg); |
177 | if (ex instanceof ClassReader.BadClassFile) throw new Abort(); |
178 | else return syms.errType; |
179 | } |
180 | |
181 | /** Report a type error. |
182 | * @param pos Position to be used for error reporting. |
183 | * @param problem A string describing the error. |
184 | * @param found The type that was found. |
185 | * @param req The type that was required. |
186 | */ |
187 | Type typeError(DiagnosticPosition pos, Object problem, Type found, Type req) { |
188 | log.error(pos, "prob.found.req", |
189 | problem, found, req); |
190 | return syms.errType; |
191 | } |
192 | |
193 | Type typeError(DiagnosticPosition pos, String problem, Type found, Type req, Object explanation) { |
194 | log.error(pos, "prob.found.req.1", problem, found, req, explanation); |
195 | return syms.errType; |
196 | } |
197 | |
198 | /** Report an error that wrong type tag was found. |
199 | * @param pos Position to be used for error reporting. |
200 | * @param required An internationalized string describing the type tag |
201 | * required. |
202 | * @param found The type that was found. |
203 | */ |
204 | Type typeTagError(DiagnosticPosition pos, Object required, Object found) { |
205 | log.error(pos, "type.found.req", found, required); |
206 | return syms.errType; |
207 | } |
208 | |
209 | /** Report an error that symbol cannot be referenced before super |
210 | * has been called. |
211 | * @param pos Position to be used for error reporting. |
212 | * @param sym The referenced symbol. |
213 | */ |
214 | void earlyRefError(DiagnosticPosition pos, Symbol sym) { |
215 | log.error(pos, "cant.ref.before.ctor.called", sym); |
216 | } |
217 | |
218 | /** Report duplicate declaration error. |
219 | */ |
220 | void duplicateError(DiagnosticPosition pos, Symbol sym) { |
221 | if (!sym.type.isErroneous()) { |
222 | log.error(pos, "already.defined", sym, sym.location()); |
223 | } |
224 | } |
225 | |
226 | /** Report array/varargs duplicate declaration |
227 | */ |
228 | void varargsDuplicateError(DiagnosticPosition pos, Symbol sym1, Symbol sym2) { |
229 | if (!sym1.type.isErroneous() && !sym2.type.isErroneous()) { |
230 | log.error(pos, "array.and.varargs", sym1, sym2, sym2.location()); |
231 | } |
232 | } |
233 | |
234 | /* ************************************************************************ |
235 | * duplicate declaration checking |
236 | *************************************************************************/ |
237 | |
238 | /** Check that variable does not hide variable with same name in |
239 | * immediately enclosing local scope. |
240 | * @param pos Position for error reporting. |
241 | * @param v The symbol. |
242 | * @param s The scope. |
243 | */ |
244 | void checkTransparentVar(DiagnosticPosition pos, VarSymbol v, Scope s) { |
245 | if (s.next != null) { |
246 | for (Scope.Entry e = s.next.lookup(v.name); |
247 | e.scope != null && e.sym.owner == v.owner; |
248 | e = e.next()) { |
249 | if (e.sym.kind == VAR && |
250 | (e.sym.owner.kind & (VAR | MTH)) != 0 && |
251 | v.name != names.error) { |
252 | duplicateError(pos, e.sym); |
253 | return; |
254 | } |
255 | } |
256 | } |
257 | } |
258 | |
259 | /** Check that a class or interface does not hide a class or |
260 | * interface with same name in immediately enclosing local scope. |
261 | * @param pos Position for error reporting. |
262 | * @param c The symbol. |
263 | * @param s The scope. |
264 | */ |
265 | void checkTransparentClass(DiagnosticPosition pos, ClassSymbol c, Scope s) { |
266 | if (s.next != null) { |
267 | for (Scope.Entry e = s.next.lookup(c.name); |
268 | e.scope != null && e.sym.owner == c.owner; |
269 | e = e.next()) { |
270 | if (e.sym.kind == TYP && |
271 | (e.sym.owner.kind & (VAR | MTH)) != 0 && |
272 | c.name != names.error) { |
273 | duplicateError(pos, e.sym); |
274 | return; |
275 | } |
276 | } |
277 | } |
278 | } |
279 | |
280 | /** Check that class does not have the same name as one of |
281 | * its enclosing classes, or as a class defined in its enclosing scope. |
282 | * return true if class is unique in its enclosing scope. |
283 | * @param pos Position for error reporting. |
284 | * @param name The class name. |
285 | * @param s The enclosing scope. |
286 | */ |
287 | boolean checkUniqueClassName(DiagnosticPosition pos, Name name, Scope s) { |
288 | for (Scope.Entry e = s.lookup(name); e.scope == s; e = e.next()) { |
289 | if (e.sym.kind == TYP && e.sym.name != names.error) { |
290 | duplicateError(pos, e.sym); |
291 | return false; |
292 | } |
293 | } |
294 | for (Symbol sym = s.owner; sym != null; sym = sym.owner) { |
295 | if (sym.kind == TYP && sym.name == name && sym.name != names.error) { |
296 | duplicateError(pos, sym); |
297 | return true; |
298 | } |
299 | } |
300 | return true; |
301 | } |
302 | |
303 | /* ************************************************************************* |
304 | * Class name generation |
305 | **************************************************************************/ |
306 | |
307 | /** Return name of local class. |
308 | * This is of the form <enclClass> $ n <classname> |
309 | * where |
310 | * enclClass is the flat name of the enclosing class, |
311 | * classname is the simple name of the local class |
312 | */ |
313 | Name localClassName(ClassSymbol c) { |
314 | for (int i=1; ; i++) { |
315 | Name flatname = names. |
316 | fromString("" + c.owner.enclClass().flatname + |
317 | target.syntheticNameChar() + i + |
318 | c.name); |
319 | if (compiled.get(flatname) == null) return flatname; |
320 | } |
321 | } |
322 | |
323 | /* ************************************************************************* |
324 | * Type Checking |
325 | **************************************************************************/ |
326 | |
327 | /** Check that a given type is assignable to a given proto-type. |
328 | * If it is, return the type, otherwise return errType. |
329 | * @param pos Position to be used for error reporting. |
330 | * @param found The type that was found. |
331 | * @param req The type that was required. |
332 | */ |
333 | Type checkType(DiagnosticPosition pos, Type found, Type req) { |
334 | if (req.tag == ERROR) |
335 | return req; |
336 | if (found.tag == FORALL) |
337 | return instantiatePoly(pos, (ForAll)found, req, convertWarner(pos, found, req)); |
338 | if (req.tag == NONE) |
339 | return found; |
340 | if (types.isAssignable(found, req, convertWarner(pos, found, req))) |
341 | return found; |
342 | if (found.tag <= DOUBLE && req.tag <= DOUBLE) |
343 | return typeError(pos, JCDiagnostic.fragment("possible.loss.of.precision"), found, req); |
344 | if (found.isSuperBound()) { |
345 | log.error(pos, "assignment.from.super-bound", found); |
346 | return syms.errType; |
347 | } |
348 | if (req.isExtendsBound()) { |
349 | log.error(pos, "assignment.to.extends-bound", req); |
350 | return syms.errType; |
351 | } |
352 | return typeError(pos, JCDiagnostic.fragment("incompatible.types"), found, req); |
353 | } |
354 | |
355 | /** Instantiate polymorphic type to some prototype, unless |
356 | * prototype is `anyPoly' in which case polymorphic type |
357 | * is returned unchanged. |
358 | */ |
359 | Type instantiatePoly(DiagnosticPosition pos, ForAll t, Type pt, Warner warn) { |
360 | if (pt == Infer.anyPoly && complexInference) { |
361 | return t; |
362 | } else if (pt == Infer.anyPoly || pt.tag == NONE) { |
363 | Type newpt = t.qtype.tag <= VOID ? t.qtype : syms.objectType; |
364 | return instantiatePoly(pos, t, newpt, warn); |
365 | } else if (pt.tag == ERROR) { |
366 | return pt; |
367 | } else { |
368 | try { |
369 | return infer.instantiateExpr(t, pt, warn); |
370 | } catch (Infer.NoInstanceException ex) { |
371 | if (ex.isAmbiguous) { |
372 | JCDiagnostic d = ex.getDiagnostic(); |
373 | log.error(pos, |
374 | "undetermined.type" + (d!=null ? ".1" : ""), |
375 | t, d); |
376 | return syms.errType; |
377 | } else { |
378 | JCDiagnostic d = ex.getDiagnostic(); |
379 | return typeError(pos, |
380 | JCDiagnostic.fragment("incompatible.types" + (d!=null ? ".1" : ""), d), |
381 | t, pt); |
382 | } |
383 | } |
384 | } |
385 | } |
386 | |
387 | /** Check that a given type can be cast to a given target type. |
388 | * Return the result of the cast. |
389 | * @param pos Position to be used for error reporting. |
390 | * @param found The type that is being cast. |
391 | * @param req The target type of the cast. |
392 | */ |
393 | Type checkCastable(DiagnosticPosition pos, Type found, Type req) { |
394 | if (found.tag == FORALL) { |
395 | instantiatePoly(pos, (ForAll) found, req, castWarner(pos, found, req)); |
396 | return req; |
397 | } else if (types.isCastable(found, req, castWarner(pos, found, req))) { |
398 | return req; |
399 | } else { |
400 | return typeError(pos, |
401 | JCDiagnostic.fragment("inconvertible.types"), |
402 | found, req); |
403 | } |
404 | } |
405 | //where |
406 | /** Is type a type variable, or a (possibly multi-dimensional) array of |
407 | * type variables? |
408 | */ |
409 | boolean isTypeVar(Type t) { |
410 | return t.tag == TYPEVAR || t.tag == ARRAY && isTypeVar(types.elemtype(t)); |
411 | } |
412 | |
413 | /** Check that a type is within some bounds. |
414 | * |
415 | * Used in TypeApply to verify that, e.g., X in V<X> is a valid |
416 | * type argument. |
417 | * @param pos Position to be used for error reporting. |
418 | * @param a The type that should be bounded by bs. |
419 | * @param bs The bound. |
420 | */ |
421 | private void checkExtends(DiagnosticPosition pos, Type a, TypeVar bs) { |
422 | if (a.isUnbound()) { |
423 | return; |
424 | } else if (a.tag != WILDCARD) { |
425 | a = types.upperBound(a); |
426 | for (List<Type> l = types.getBounds(bs); l.nonEmpty(); l = l.tail) { |
427 | if (!types.isSubtype(a, l.head)) { |
428 | log.error(pos, "not.within.bounds", a); |
429 | return; |
430 | } |
431 | } |
432 | } else if (a.isExtendsBound()) { |
433 | if (!types.isCastable(bs.getUpperBound(), types.upperBound(a), Warner.noWarnings)) |
434 | log.error(pos, "not.within.bounds", a); |
435 | } else if (a.isSuperBound()) { |
436 | if (types.notSoftSubtype(types.lowerBound(a), bs.getUpperBound())) |
437 | log.error(pos, "not.within.bounds", a); |
438 | } |
439 | } |
440 | |
441 | /** Check that type is different from 'void'. |
442 | * @param pos Position to be used for error reporting. |
443 | * @param t The type to be checked. |
444 | */ |
445 | Type checkNonVoid(DiagnosticPosition pos, Type t) { |
446 | if (t.tag == VOID) { |
447 | log.error(pos, "void.not.allowed.here"); |
448 | return syms.errType; |
449 | } else { |
450 | return t; |
451 | } |
452 | } |
453 | |
454 | /** Check that type is a class or interface type. |
455 | * @param pos Position to be used for error reporting. |
456 | * @param t The type to be checked. |
457 | */ |
458 | Type checkClassType(DiagnosticPosition pos, Type t) { |
459 | if (t.tag != CLASS && t.tag != ERROR) |
460 | return typeTagError(pos, |
461 | JCDiagnostic.fragment("type.req.class"), |
462 | (t.tag == TYPEVAR) |
463 | ? JCDiagnostic.fragment("type.parameter", t) |
464 | : t); |
465 | else |
466 | return t; |
467 | } |
468 | |
469 | /** Check that type is a class or interface type. |
470 | * @param pos Position to be used for error reporting. |
471 | * @param t The type to be checked. |
472 | * @param noBounds True if type bounds are illegal here. |
473 | */ |
474 | Type checkClassType(DiagnosticPosition pos, Type t, boolean noBounds) { |
475 | t = checkClassType(pos, t); |
476 | if (noBounds && t.isParameterized()) { |
477 | List<Type> args = t.getTypeArguments(); |
478 | while (args.nonEmpty()) { |
479 | if (args.head.tag == WILDCARD) |
480 | return typeTagError(pos, |
481 | log.getLocalizedString("type.req.exact"), |
482 | args.head); |
483 | args = args.tail; |
484 | } |
485 | } |
486 | return t; |
487 | } |
488 | |
489 | /** Check that type is a reifiable class, interface or array type. |
490 | * @param pos Position to be used for error reporting. |
491 | * @param t The type to be checked. |
492 | */ |
493 | Type checkReifiableReferenceType(DiagnosticPosition pos, Type t) { |
494 | if (t.tag != CLASS && t.tag != ARRAY && t.tag != ERROR) { |
495 | return typeTagError(pos, |
496 | JCDiagnostic.fragment("type.req.class.array"), |
497 | t); |
498 | } else if (!types.isReifiable(t)) { |
499 | log.error(pos, "illegal.generic.type.for.instof"); |
500 | return syms.errType; |
501 | } else { |
502 | return t; |
503 | } |
504 | } |
505 | |
506 | /** Check that type is a reference type, i.e. a class, interface or array type |
507 | * or a type variable. |
508 | * @param pos Position to be used for error reporting. |
509 | * @param t The type to be checked. |
510 | */ |
511 | Type checkRefType(DiagnosticPosition pos, Type t) { |
512 | switch (t.tag) { |
513 | case CLASS: |
514 | case ARRAY: |
515 | case TYPEVAR: |
516 | case WILDCARD: |
517 | case ERROR: |
518 | return t; |
519 | default: |
520 | return typeTagError(pos, |
521 | JCDiagnostic.fragment("type.req.ref"), |
522 | t); |
523 | } |
524 | } |
525 | |
526 | /** Check that type is a null or reference type. |
527 | * @param pos Position to be used for error reporting. |
528 | * @param t The type to be checked. |
529 | */ |
530 | Type checkNullOrRefType(DiagnosticPosition pos, Type t) { |
531 | switch (t.tag) { |
532 | case CLASS: |
533 | case ARRAY: |
534 | case TYPEVAR: |
535 | case WILDCARD: |
536 | case BOT: |
537 | case ERROR: |
538 | return t; |
539 | default: |
540 | return typeTagError(pos, |
541 | JCDiagnostic.fragment("type.req.ref"), |
542 | t); |
543 | } |
544 | } |
545 | |
546 | /** Check that flag set does not contain elements of two conflicting sets. s |
547 | * Return true if it doesn't. |
548 | * @param pos Position to be used for error reporting. |
549 | * @param flags The set of flags to be checked. |
550 | * @param set1 Conflicting flags set #1. |
551 | * @param set2 Conflicting flags set #2. |
552 | */ |
553 | boolean checkDisjoint(DiagnosticPosition pos, long flags, long set1, long set2) { |
554 | if ((flags & set1) != 0 && (flags & set2) != 0) { |
555 | log.error(pos, |
556 | "illegal.combination.of.modifiers", |
557 | TreeInfo.flagNames(TreeInfo.firstFlag(flags & set1)), |
558 | TreeInfo.flagNames(TreeInfo.firstFlag(flags & set2))); |
559 | return false; |
560 | } else |
561 | return true; |
562 | } |
563 | |
564 | /** Check that given modifiers are legal for given symbol and |
565 | * return modifiers together with any implicit modififiers for that symbol. |
566 | * Warning: we can't use flags() here since this method |
567 | * is called during class enter, when flags() would cause a premature |
568 | * completion. |
569 | * @param pos Position to be used for error reporting. |
570 | * @param flags The set of modifiers given in a definition. |
571 | * @param sym The defined symbol. |
572 | */ |
573 | long checkFlags(DiagnosticPosition pos, long flags, Symbol sym, JCTree tree) { |
574 | long mask; |
575 | long implicit = 0; |
576 | switch (sym.kind) { |
577 | case VAR: |
578 | if (sym.owner.kind != TYP) |
579 | mask = LocalVarFlags; |
580 | else if ((sym.owner.flags_field & INTERFACE) != 0) |
581 | mask = implicit = InterfaceVarFlags; |
582 | else |
583 | mask = VarFlags; |
584 | break; |
585 | case MTH: |
586 | if (sym.name == names.init) { |
587 | if ((sym.owner.flags_field & ENUM) != 0) { |
588 | // enum constructors cannot be declared public or |
589 | // protected and must be implicitly or explicitly |
590 | // private |
591 | implicit = PRIVATE; |
592 | mask = PRIVATE; |
593 | } else |
594 | mask = ConstructorFlags; |
595 | } else if ((sym.owner.flags_field & INTERFACE) != 0) |
596 | mask = implicit = InterfaceMethodFlags; |
597 | else { |
598 | mask = MethodFlags; |
599 | } |
600 | // Imply STRICTFP if owner has STRICTFP set. |
601 | if (((flags|implicit) & Flags.ABSTRACT) == 0) |
602 | implicit |= sym.owner.flags_field & STRICTFP; |
603 | break; |
604 | case TYP: |
605 | if (sym.isLocal()) { |
606 | mask = LocalClassFlags; |
607 | if (sym.name.len == 0) { // Anonymous class |
608 | // Anonymous classes in static methods are themselves static; |
609 | // that's why we admit STATIC here. |
610 | mask |= STATIC; |
611 | // JLS: Anonymous classes are final. |
612 | implicit |= FINAL; |
613 | } |
614 | if ((sym.owner.flags_field & STATIC) == 0 && |
615 | (flags & ENUM) != 0) |
616 | log.error(pos, "enums.must.be.static"); |
617 | } else if (sym.owner.kind == TYP) { |
618 | mask = MemberClassFlags; |
619 | if (sym.owner.owner.kind == PCK || |
620 | (sym.owner.flags_field & STATIC) != 0) |
621 | mask |= STATIC; |
622 | else if ((flags & ENUM) != 0) |
623 | log.error(pos, "enums.must.be.static"); |
624 | // Nested interfaces and enums are always STATIC (Spec ???) |
625 | if ((flags & (INTERFACE | ENUM)) != 0 ) implicit = STATIC; |
626 | } else { |
627 | mask = ClassFlags; |
628 | } |
629 | // Interfaces are always ABSTRACT |
630 | if ((flags & INTERFACE) != 0) implicit |= ABSTRACT; |
631 | |
632 | if ((flags & ENUM) != 0) { |
633 | // enums can't be declared abstract or final |
634 | mask &= ~(ABSTRACT | FINAL); |
635 | implicit |= implicitEnumFinalFlag(tree); |
636 | } |
637 | // Imply STRICTFP if owner has STRICTFP set. |
638 | implicit |= sym.owner.flags_field & STRICTFP; |
639 | break; |
640 | default: |
641 | throw new AssertionError(); |
642 | } |
643 | long illegal = flags & StandardFlags & ~mask; |
644 | if (illegal != 0) { |
645 | if ((illegal & INTERFACE) != 0) { |
646 | log.error(pos, "intf.not.allowed.here"); |
647 | mask |= INTERFACE; |
648 | } |
649 | else { |
650 | log.error(pos, |
651 | "mod.not.allowed.here", TreeInfo.flagNames(illegal)); |
652 | } |
653 | } |
654 | else if ((sym.kind == TYP || |
655 | // ISSUE: Disallowing abstract&private is no longer appropriate |
656 | // in the presence of inner classes. Should it be deleted here? |
657 | checkDisjoint(pos, flags, |
658 | ABSTRACT, |
659 | PRIVATE | STATIC)) |
660 | && |
661 | checkDisjoint(pos, flags, |
662 | ABSTRACT | INTERFACE, |
663 | FINAL | NATIVE | SYNCHRONIZED) |
664 | && |
665 | checkDisjoint(pos, flags, |
666 | PUBLIC, |
667 | PRIVATE | PROTECTED) |
668 | && |
669 | checkDisjoint(pos, flags, |
670 | PRIVATE, |
671 | PUBLIC | PROTECTED) |
672 | && |
673 | checkDisjoint(pos, flags, |
674 | FINAL, |
675 | VOLATILE) |
676 | && |
677 | (sym.kind == TYP || |
678 | checkDisjoint(pos, flags, |
679 | ABSTRACT | NATIVE, |
680 | STRICTFP))) { |
681 | // skip |
682 | } |
683 | return flags & (mask | ~StandardFlags) | implicit; |
684 | } |
685 | |
686 | |
687 | /** Determine if this enum should be implicitly final. |
688 | * |
689 | * If the enum has no specialized enum contants, it is final. |
690 | * |
691 | * If the enum does have specialized enum contants, it is |
692 | * <i>not</i> final. |
693 | */ |
694 | private long implicitEnumFinalFlag(JCTree tree) { |
695 | if (tree.getTag() != JCTree.CLASSDEF) return 0; |
696 | class SpecialTreeVisitor extends JCTree.Visitor { |
697 | boolean specialized; |
698 | SpecialTreeVisitor() { |
699 | this.specialized = false; |
700 | }; |
701 | |
702 | public void visitTree(JCTree tree) { /* no-op */ } |
703 | |
704 | public void visitVarDef(JCVariableDecl tree) { |
705 | if ((tree.mods.flags & ENUM) != 0) { |
706 | if (tree.init instanceof JCNewClass && |
707 | ((JCNewClass) tree.init).def != null) { |
708 | specialized = true; |
709 | } |
710 | } |
711 | } |
712 | } |
713 | |
714 | SpecialTreeVisitor sts = new SpecialTreeVisitor(); |
715 | JCClassDecl cdef = (JCClassDecl) tree; |
716 | for (JCTree defs: cdef.defs) { |
717 | defs.accept(sts); |
718 | if (sts.specialized) return 0; |
719 | } |
720 | return FINAL; |
721 | } |
722 | |
723 | /* ************************************************************************* |
724 | * Type Validation |
725 | **************************************************************************/ |
726 | |
727 | /** Validate a type expression. That is, |
728 | * check that all type arguments of a parametric type are within |
729 | * their bounds. This must be done in a second phase after type attributon |
730 | * since a class might have a subclass as type parameter bound. E.g: |
731 | * |
732 | * class B<A extends C> { ... } |
733 | * class C extends B<C> { ... } |
734 | * |
735 | * and we can't make sure that the bound is already attributed because |
736 | * of possible cycles. |
737 | */ |
738 | private Validator validator = new Validator(); |
739 | |
740 | /** Visitor method: Validate a type expression, if it is not null, catching |
741 | * and reporting any completion failures. |
742 | */ |
743 | void validate(JCTree tree) { |
744 | try { |
745 | if (tree != null) tree.accept(validator); |
746 | } catch (CompletionFailure ex) { |
747 | completionError(tree.pos(), ex); |
748 | } |
749 | } |
750 | |
751 | /** Visitor method: Validate a list of type expressions. |
752 | */ |
753 | void validate(List<? extends JCTree> trees) { |
754 | for (List<? extends JCTree> l = trees; l.nonEmpty(); l = l.tail) |
755 | validate(l.head); |
756 | } |
757 | |
758 | /** Visitor method: Validate a list of type parameters. |
759 | */ |
760 | void validateTypeParams(List<JCTypeParameter> trees) { |
761 | for (List<JCTypeParameter> l = trees; l.nonEmpty(); l = l.tail) |
762 | validate(l.head); |
763 | } |
764 | |
765 | /** A visitor class for type validation. |
766 | */ |
767 | class Validator extends JCTree.Visitor { |
768 | |
769 | public void visitTypeArray(JCArrayTypeTree tree) { |
770 | validate(tree.elemtype); |
771 | } |
772 | |
773 | public void visitTypeApply(JCTypeApply tree) { |
774 | if (tree.type.tag == CLASS) { |
775 | List<Type> formals = tree.type.tsym.type.getTypeArguments(); |
776 | List<Type> actuals = tree.type.getTypeArguments(); |
777 | List<JCExpression> args = tree.arguments; |
778 | List<Type> forms = formals; |
779 | ListBuffer<TypeVar> tvars_buf = new ListBuffer<TypeVar>(); |
780 | |
781 | // For matching pairs of actual argument types `a' and |
782 | // formal type parameters with declared bound `b' ... |
783 | while (args.nonEmpty() && forms.nonEmpty()) { |
784 | validate(args.head); |
785 | |
786 | // exact type arguments needs to know their |
787 | // bounds (for upper and lower bound |
788 | // calculations). So we create new TypeVars with |
789 | // bounds substed with actuals. |
790 | tvars_buf.append(types.substBound(((TypeVar)forms.head), |
791 | formals, |
792 | Type.removeBounds(actuals))); |
793 | |
794 | args = args.tail; |
795 | forms = forms.tail; |
796 | } |
797 | |
798 | args = tree.arguments; |
799 | List<TypeVar> tvars = tvars_buf.toList(); |
800 | while (args.nonEmpty() && tvars.nonEmpty()) { |
801 | // Let the actual arguments know their bound |
802 | args.head.type.withTypeVar(tvars.head); |
803 | args = args.tail; |
804 | tvars = tvars.tail; |
805 | } |
806 | |
807 | args = tree.arguments; |
808 | tvars = tvars_buf.toList(); |
809 | while (args.nonEmpty() && tvars.nonEmpty()) { |
810 | checkExtends(args.head.pos(), |
811 | args.head.type, |
812 | tvars.head); |
813 | args = args.tail; |
814 | tvars = tvars.tail; |
815 | } |
816 | |
817 | // Check that this type is either fully parameterized, or |
818 | // not parameterized at all. |
819 | if (tree.type.getEnclosingType().isRaw()) |
820 | log.error(tree.pos(), "improperly.formed.type.inner.raw.param"); |
821 | if (tree.clazz.getTag() == JCTree.SELECT) |
822 | visitSelectInternal((JCFieldAccess)tree.clazz); |
823 | } |
824 | } |
825 | |
826 | public void visitTypeParameter(JCTypeParameter tree) { |
827 | validate(tree.bounds); |
828 | checkClassBounds(tree.pos(), tree.type); |
829 | } |
830 | |
831 | @Override |
832 | public void visitWildcard(JCWildcard tree) { |
833 | if (tree.inner != null) |
834 | validate(tree.inner); |
835 | } |
836 | |
837 | public void visitSelect(JCFieldAccess tree) { |
838 | if (tree.type.tag == CLASS) { |
839 | visitSelectInternal(tree); |
840 | |
841 | // Check that this type is either fully parameterized, or |
842 | // not parameterized at all. |
843 | if (tree.selected.type.isParameterized() && tree.type.tsym.type.getTypeArguments().nonEmpty()) |
844 | log.error(tree.pos(), "improperly.formed.type.param.missing"); |
845 | } |
846 | } |
847 | public void visitSelectInternal(JCFieldAccess tree) { |
848 | if (tree.type.getEnclosingType().tag != CLASS && |
849 | tree.selected.type.isParameterized()) { |
850 | // The enclosing type is not a class, so we are |
851 | // looking at a static member type. However, the |
852 | // qualifying expression is parameterized. |
853 | log.error(tree.pos(), "cant.select.static.class.from.param.type"); |
854 | } else { |
855 | // otherwise validate the rest of the expression |
856 | validate(tree.selected); |
857 | } |
858 | } |
859 | |
860 | /** Default visitor method: do nothing. |
861 | */ |
862 | public void visitTree(JCTree tree) { |
863 | } |
864 | } |
865 | |
866 | /* ************************************************************************* |
867 | * Exception checking |
868 | **************************************************************************/ |
869 | |
870 | /* The following methods treat classes as sets that contain |
871 | * the class itself and all their subclasses |
872 | */ |
873 | |
874 | /** Is given type a subtype of some of the types in given list? |
875 | */ |
876 | boolean subset(Type t, List<Type> ts) { |
877 | for (List<Type> l = ts; l.nonEmpty(); l = l.tail) |
878 | if (types.isSubtype(t, l.head)) return true; |
879 | return false; |
880 | } |
881 | |
882 | /** Is given type a subtype or supertype of |
883 | * some of the types in given list? |
884 | */ |
885 | boolean intersects(Type t, List<Type> ts) { |
886 | for (List<Type> l = ts; l.nonEmpty(); l = l.tail) |
887 | if (types.isSubtype(t, l.head) || types.isSubtype(l.head, t)) return true; |
888 | return false; |
889 | } |
890 | |
891 | /** Add type set to given type list, unless it is a subclass of some class |
892 | * in the list. |
893 | */ |
894 | List<Type> incl(Type t, List<Type> ts) { |
895 | return subset(t, ts) ? ts : excl(t, ts).prepend(t); |
896 | } |
897 | |
898 | /** Remove type set from type set list. |
899 | */ |
900 | List<Type> excl(Type t, List<Type> ts) { |
901 | if (ts.isEmpty()) { |
902 | return ts; |
903 | } else { |
904 | List<Type> ts1 = excl(t, ts.tail); |
905 | if (types.isSubtype(ts.head, t)) return ts1; |
906 | else if (ts1 == ts.tail) return ts; |
907 | else return ts1.prepend(ts.head); |
908 | } |
909 | } |
910 | |
911 | /** Form the union of two type set lists. |
912 | */ |
913 | List<Type> union(List<Type> ts1, List<Type> ts2) { |
914 | List<Type> ts = ts1; |
915 | for (List<Type> l = ts2; l.nonEmpty(); l = l.tail) |
916 | ts = incl(l.head, ts); |
917 | return ts; |
918 | } |
919 | |
920 | /** Form the difference of two type lists. |
921 | */ |
922 | List<Type> diff(List<Type> ts1, List<Type> ts2) { |
923 | List<Type> ts = ts1; |
924 | for (List<Type> l = ts2; l.nonEmpty(); l = l.tail) |
925 | ts = excl(l.head, ts); |
926 | return ts; |
927 | } |
928 | |
929 | /** Form the intersection of two type lists. |
930 | */ |
931 | public List<Type> intersect(List<Type> ts1, List<Type> ts2) { |
932 | List<Type> ts = List.nil(); |
933 | for (List<Type> l = ts1; l.nonEmpty(); l = l.tail) |
934 | if (subset(l.head, ts2)) ts = incl(l.head, ts); |
935 | for (List<Type> l = ts2; l.nonEmpty(); l = l.tail) |
936 | if (subset(l.head, ts1)) ts = incl(l.head, ts); |
937 | return ts; |
938 | } |
939 | |
940 | /** Is exc an exception symbol that need not be declared? |
941 | */ |
942 | boolean isUnchecked(ClassSymbol exc) { |
943 | return |
944 | exc.kind == ERR || |
945 | exc.isSubClass(syms.errorType.tsym, types) || |
946 | exc.isSubClass(syms.runtimeExceptionType.tsym, types); |
947 | } |
948 | |
949 | /** Is exc an exception type that need not be declared? |
950 | */ |
951 | boolean isUnchecked(Type exc) { |
952 | return |
953 | (exc.tag == TYPEVAR) ? isUnchecked(types.supertype(exc)) : |
954 | (exc.tag == CLASS) ? isUnchecked((ClassSymbol)exc.tsym) : |
955 | exc.tag == BOT; |
956 | } |
957 | |
958 | /** Same, but handling completion failures. |
959 | */ |
960 | boolean isUnchecked(DiagnosticPosition pos, Type exc) { |
961 | try { |
962 | return isUnchecked(exc); |
963 | } catch (CompletionFailure ex) { |
964 | completionError(pos, ex); |
965 | return true; |
966 | } |
967 | } |
968 | |
969 | /** Is exc handled by given exception list? |
970 | */ |
971 | boolean isHandled(Type exc, List<Type> handled) { |
972 | return isUnchecked(exc) || subset(exc, handled); |
973 | } |
974 | |
975 | /** Return all exceptions in thrown list that are not in handled list. |
976 | * @param thrown The list of thrown exceptions. |
977 | * @param handled The list of handled exceptions. |
978 | */ |
979 | List<Type> unHandled(List<Type> thrown, List<Type> handled) { |
980 | List<Type> unhandled = List.nil(); |
981 | for (List<Type> l = thrown; l.nonEmpty(); l = l.tail) |
982 | if (!isHandled(l.head, handled)) unhandled = unhandled.prepend(l.head); |
983 | return unhandled; |
984 | } |
985 | |
986 | /* ************************************************************************* |
987 | * Overriding/Implementation checking |
988 | **************************************************************************/ |
989 | |
990 | /** The level of access protection given by a flag set, |
991 | * where PRIVATE is highest and PUBLIC is lowest. |
992 | */ |
993 | static int protection(long flags) { |
994 | switch ((short)(flags & AccessFlags)) { |
995 | case PRIVATE: return 3; |
996 | case PROTECTED: return 1; |
997 | default: |
998 | case PUBLIC: return 0; |
999 | case 0: return 2; |
1000 | } |
1001 | } |
1002 | |
1003 | /** A string describing the access permission given by a flag set. |
1004 | * This always returns a space-separated list of Java Keywords. |
1005 | */ |
1006 | private static String protectionString(long flags) { |
1007 | long flags1 = flags & AccessFlags; |
1008 | return (flags1 == 0) ? "package" : TreeInfo.flagNames(flags1); |
1009 | } |
1010 | |
1011 | /** A customized "cannot override" error message. |
1012 | * @param m The overriding method. |
1013 | * @param other The overridden method. |
1014 | * @return An internationalized string. |
1015 | */ |
1016 | static Object cannotOverride(MethodSymbol m, MethodSymbol other) { |
1017 | String key; |
1018 | if ((other.owner.flags() & INTERFACE) == 0) |
1019 | key = "cant.override"; |
1020 | else if ((m.owner.flags() & INTERFACE) == 0) |
1021 | key = "cant.implement"; |
1022 | else |
1023 | key = "clashes.with"; |
1024 | return JCDiagnostic.fragment(key, m, m.location(), other, other.location()); |
1025 | } |
1026 | |
1027 | /** A customized "override" warning message. |
1028 | * @param m The overriding method. |
1029 | * @param other The overridden method. |
1030 | * @return An internationalized string. |
1031 | */ |
1032 | static Object uncheckedOverrides(MethodSymbol m, MethodSymbol other) { |
1033 | String key; |
1034 | if ((other.owner.flags() & INTERFACE) == 0) |
1035 | key = "unchecked.override"; |
1036 | else if ((m.owner.flags() & INTERFACE) == 0) |
1037 | key = "unchecked.implement"; |
1038 | else |
1039 | key = "unchecked.clash.with"; |
1040 | return JCDiagnostic.fragment(key, m, m.location(), other, other.location()); |
1041 | } |
1042 | |
1043 | /** A customized "override" warning message. |
1044 | * @param m The overriding method. |
1045 | * @param other The overridden method. |
1046 | * @return An internationalized string. |
1047 | */ |
1048 | static Object varargsOverrides(MethodSymbol m, MethodSymbol other) { |
1049 | String key; |
1050 | if ((other.owner.flags() & INTERFACE) == 0) |
1051 | key = "varargs.override"; |
1052 | else if ((m.owner.flags() & INTERFACE) == 0) |
1053 | key = "varargs.implement"; |
1054 | else |
1055 | key = "varargs.clash.with"; |
1056 | return JCDiagnostic.fragment(key, m, m.location(), other, other.location()); |
1057 | } |
1058 | |
1059 | /** Check that this method conforms with overridden method 'other'. |
1060 | * where `origin' is the class where checking started. |
1061 | * Complications: |
1062 | * (1) Do not check overriding of synthetic methods |
1063 | * (reason: they might be final). |
1064 | * todo: check whether this is still necessary. |
1065 | * (2) Admit the case where an interface proxy throws fewer exceptions |
1066 | * than the method it implements. Augment the proxy methods with the |
1067 | * undeclared exceptions in this case. |
1068 | * (3) When generics are enabled, admit the case where an interface proxy |
1069 | * has a result type |
1070 | * extended by the result type of the method it implements. |
1071 | * Change the proxies result type to the smaller type in this case. |
1072 | * |
1073 | * @param tree The tree from which positions |
1074 | * are extracted for errors. |
1075 | * @param m The overriding method. |
1076 | * @param other The overridden method. |
1077 | * @param origin The class of which the overriding method |
1078 | * is a member. |
1079 | */ |
1080 | void checkOverride(JCTree tree, |
1081 | MethodSymbol m, |
1082 | MethodSymbol other, |
1083 | ClassSymbol origin) { |
1084 | // Don't check overriding of synthetic methods or by bridge methods. |
1085 | if ((m.flags() & (SYNTHETIC|BRIDGE)) != 0 || (other.flags() & SYNTHETIC) != 0) { |
1086 | return; |
1087 | } |
1088 | |
1089 | // Error if static method overrides instance method (JLS 8.4.6.2). |
1090 | if ((m.flags() & STATIC) != 0 && |
1091 | (other.flags() & STATIC) == 0) { |
1092 | log.error(TreeInfo.diagnosticPositionFor(m, tree), "override.static", |
1093 | cannotOverride(m, other)); |
1094 | return; |
1095 | } |
1096 | |
1097 | // Error if instance method overrides static or final |
1098 | // method (JLS 8.4.6.1). |
1099 | if ((other.flags() & FINAL) != 0 || |
1100 | (m.flags() & STATIC) == 0 && |
1101 | (other.flags() & STATIC) != 0) { |
1102 | log.error(TreeInfo.diagnosticPositionFor(m, tree), "override.meth", |
1103 | cannotOverride(m, other), |
1104 | TreeInfo.flagNames(other.flags() & (FINAL | STATIC))); |
1105 | return; |
1106 | } |
1107 | |
1108 | if ((m.owner.flags() & ANNOTATION) != 0) { |
1109 | // handled in validateAnnotationMethod |
1110 | return; |
1111 | } |
1112 | |
1113 | // Error if overriding method has weaker access (JLS 8.4.6.3). |
1114 | if ((origin.flags() & INTERFACE) == 0 && |
1115 | protection(m.flags()) > protection(other.flags())) { |
1116 | log.error(TreeInfo.diagnosticPositionFor(m, tree), "override.weaker.access", |
1117 | cannotOverride(m, other), |
1118 | protectionString(other.flags())); |
1119 | return; |
1120 | |
1121 | } |
1122 | |
1123 | Type mt = types.memberType(origin.type, m); |
1124 | Type ot = types.memberType(origin.type, other); |
1125 | // Error if overriding result type is different |
1126 | // (or, in the case of generics mode, not a subtype) of |
1127 | // overridden result type. We have to rename any type parameters |
1128 | // before comparing types. |
1129 | List<Type> mtvars = mt.getTypeArguments(); |
1130 | List<Type> otvars = ot.getTypeArguments(); |
1131 | Type mtres = mt.getReturnType(); |
1132 | Type otres = types.subst(ot.getReturnType(), otvars, mtvars); |
1133 | |
1134 | overrideWarner.warned = false; |
1135 | boolean resultTypesOK = |
1136 | types.returnTypeSubstitutable(mt, ot, otres, overrideWarner); |
1137 | if (!resultTypesOK) { |
1138 | if (!source.allowCovariantReturns() && |
1139 | m.owner != origin && |
1140 | m.owner.isSubClass(other.owner, types)) { |
1141 | // allow limited interoperability with covariant returns |
1142 | } else { |
1143 | typeError(TreeInfo.diagnosticPositionFor(m, tree), |
1144 | JCDiagnostic.fragment("override.incompatible.ret", |
1145 | cannotOverride(m, other)), |
1146 | mtres, otres); |
1147 | return; |
1148 | } |
1149 | } else if (overrideWarner.warned) { |
1150 | warnUnchecked(TreeInfo.diagnosticPositionFor(m, tree), |
1151 | "prob.found.req", |
1152 | JCDiagnostic.fragment("override.unchecked.ret", |
1153 | uncheckedOverrides(m, other)), |
1154 | mtres, otres); |
1155 | } |
1156 | |
1157 | // Error if overriding method throws an exception not reported |
1158 | // by overridden method. |
1159 | List<Type> otthrown = types.subst(ot.getThrownTypes(), otvars, mtvars); |
1160 | List<Type> unhandled = unHandled(mt.getThrownTypes(), otthrown); |
1161 | if (unhandled.nonEmpty()) { |
1162 | log.error(TreeInfo.diagnosticPositionFor(m, tree), |
1163 | "override.meth.doesnt.throw", |
1164 | cannotOverride(m, other), |
1165 | unhandled.head); |
1166 | return; |
1167 | } |
1168 | |
1169 | // Optional warning if varargs don't agree |
1170 | if ((((m.flags() ^ other.flags()) & Flags.VARARGS) != 0) |
1171 | && lint.isEnabled(Lint.LintCategory.OVERRIDES)) { |
1172 | log.warning(TreeInfo.diagnosticPositionFor(m, tree), |
1173 | ((m.flags() & Flags.VARARGS) != 0) |
1174 | ? "override.varargs.missing" |
1175 | : "override.varargs.extra", |
1176 | varargsOverrides(m, other)); |
1177 | } |
1178 | |
1179 | // Warn if instance method overrides bridge method (compiler spec ??) |
1180 | if ((other.flags() & BRIDGE) != 0) { |
1181 | log.warning(TreeInfo.diagnosticPositionFor(m, tree), "override.bridge", |
1182 | uncheckedOverrides(m, other)); |
1183 | } |
1184 | |
1185 | // Warn if a deprecated method overridden by a non-deprecated one. |
1186 | if ((other.flags() & DEPRECATED) != 0 |
1187 | && (m.flags() & DEPRECATED) == 0 |
1188 | && m.outermostClass() != other.outermostClass() |
1189 | && !isDeprecatedOverrideIgnorable(other, origin)) { |
1190 | warnDeprecated(TreeInfo.diagnosticPositionFor(m, tree), other); |
1191 | } |
1192 | } |
1193 | // where |
1194 | private boolean isDeprecatedOverrideIgnorable(MethodSymbol m, ClassSymbol origin) { |
1195 | // If the method, m, is defined in an interface, then ignore the issue if the method |
1196 | // is only inherited via a supertype and also implemented in the supertype, |
1197 | // because in that case, we will rediscover the issue when examining the method |
1198 | // in the supertype. |
1199 | // If the method, m, is not defined in an interface, then the only time we need to |
1200 | // address the issue is when the method is the supertype implemementation: any other |
1201 | // case, we will have dealt with when examining the supertype classes |
1202 | ClassSymbol mc = m.enclClass(); |
1203 | Type st = types.supertype(origin.type); |
1204 | if (st.tag != CLASS) |
1205 | return true; |
1206 | MethodSymbol stimpl = m.implementation((ClassSymbol)st.tsym, types, false); |
1207 | |
1208 | if (mc != null && ((mc.flags() & INTERFACE) != 0)) { |
1209 | List<Type> intfs = types.interfaces(origin.type); |
1210 | return (intfs.contains(mc.type) ? false : (stimpl != null)); |
1211 | } |
1212 | else |
1213 | return (stimpl != m); |
1214 | } |
1215 | |
1216 | |
1217 | // used to check if there were any unchecked conversions |
1218 | Warner overrideWarner = new Warner(); |
1219 | |
1220 | /** Check that a class does not inherit two concrete methods |
1221 | * with the same signature. |
1222 | * @param pos Position to be used for error reporting. |
1223 | * @param site The class type to be checked. |
1224 | */ |
1225 | public void checkCompatibleConcretes(DiagnosticPosition pos, Type site) { |
1226 | Type sup = types.supertype(site); |
1227 | if (sup.tag != CLASS) return; |
1228 | |
1229 | for (Type t1 = sup; |
1230 | t1.tsym.type.isParameterized(); |
1231 | t1 = types.supertype(t1)) { |
1232 | for (Scope.Entry e1 = t1.tsym.members().elems; |
1233 | e1 != null; |
1234 | e1 = e1.sibling) { |
1235 | Symbol s1 = e1.sym; |
1236 | if (s1.kind != MTH || |
1237 | (s1.flags() & (STATIC|SYNTHETIC|BRIDGE)) != 0 || |
1238 | !s1.isInheritedIn(site.tsym, types) || |
1239 | ((MethodSymbol)s1).implementation(site.tsym, |
1240 | types, |
1241 | true) != s1) |
1242 | continue; |
1243 | Type st1 = types.memberType(t1, s1); |
1244 | int s1ArgsLength = st1.getParameterTypes().length(); |
1245 | if (st1 == s1.type) continue; |
1246 | |
1247 | for (Type t2 = sup; |
1248 | t2.tag == CLASS; |
1249 | t2 = types.supertype(t2)) { |
1250 | for (Scope.Entry e2 = t1.tsym.members().lookup(s1.name); |
1251 | e2.scope != null; |
1252 | e2 = e2.next()) { |
1253 | Symbol s2 = e2.sym; |
1254 | if (s2 == s1 || |
1255 | s2.kind != MTH || |
1256 | (s2.flags() & (STATIC|SYNTHETIC|BRIDGE)) != 0 || |
1257 | s2.type.getParameterTypes().length() != s1ArgsLength || |
1258 | !s2.isInheritedIn(site.tsym, types) || |
1259 | ((MethodSymbol)s2).implementation(site.tsym, |
1260 | types, |
1261 | true) != s2) |
1262 | continue; |
1263 | Type st2 = types.memberType(t2, s2); |
1264 | if (types.overrideEquivalent(st1, st2)) |
1265 | log.error(pos, "concrete.inheritance.conflict", |
1266 | s1, t1, s2, t2, sup); |
1267 | } |
1268 | } |
1269 | } |
1270 | } |
1271 | } |
1272 | |
1273 | /** Check that classes (or interfaces) do not each define an abstract |
1274 | * method with same name and arguments but incompatible return types. |
1275 | * @param pos Position to be used for error reporting. |
1276 | * @param t1 The first argument type. |
1277 | * @param t2 The second argument type. |
1278 | */ |
1279 | public boolean checkCompatibleAbstracts(DiagnosticPosition pos, |
1280 | Type t1, |
1281 | Type t2) { |
1282 | return checkCompatibleAbstracts(pos, t1, t2, |
1283 | types.makeCompoundType(t1, t2)); |
1284 | } |
1285 | |
1286 | public boolean checkCompatibleAbstracts(DiagnosticPosition pos, |
1287 | Type t1, |
1288 | Type t2, |
1289 | Type site) { |
1290 | Symbol sym = firstIncompatibility(t1, t2, site); |
1291 | if (sym != null) { |
1292 | log.error(pos, "types.incompatible.diff.ret", |
1293 | t1, t2, sym.name + |
1294 | "(" + types.memberType(t2, sym).getParameterTypes() + ")"); |
1295 | return false; |
1296 | } |
1297 | return true; |
1298 | } |
1299 | |
1300 | /** Return the first method which is defined with same args |
1301 | * but different return types in two given interfaces, or null if none |
1302 | * exists. |
1303 | * @param t1 The first type. |
1304 | * @param t2 The second type. |
1305 | * @param site The most derived type. |
1306 | * @returns symbol from t2 that conflicts with one in t1. |
1307 | */ |
1308 | private Symbol firstIncompatibility(Type t1, Type t2, Type site) { |
1309 | Map<TypeSymbol,Type> interfaces1 = new HashMap<TypeSymbol,Type>(); |
1310 | closure(t1, interfaces1); |
1311 | Map<TypeSymbol,Type> interfaces2; |
1312 | if (t1 == t2) |
1313 | interfaces2 = interfaces1; |
1314 | else |
1315 | closure(t2, interfaces1, interfaces2 = new HashMap<TypeSymbol,Type>()); |
1316 | |
1317 | for (Type t3 : interfaces1.values()) { |
1318 | for (Type t4 : interfaces2.values()) { |
1319 | Symbol s = firstDirectIncompatibility(t3, t4, site); |
1320 | if (s != null) return s; |
1321 | } |
1322 | } |
1323 | return null; |
1324 | } |
1325 | |
1326 | /** Compute all the supertypes of t, indexed by type symbol. */ |
1327 | private void closure(Type t, Map<TypeSymbol,Type> typeMap) { |
1328 | if (t.tag != CLASS) return; |
1329 | if (typeMap.put(t.tsym, t) == null) { |
1330 | closure(types.supertype(t), typeMap); |
1331 | for (Type i : types.interfaces(t)) |
1332 | closure(i, typeMap); |
1333 | } |
1334 | } |
1335 | |
1336 | /** Compute all the supertypes of t, indexed by type symbol (except thise in typesSkip). */ |
1337 | private void closure(Type t, Map<TypeSymbol,Type> typesSkip, Map<TypeSymbol,Type> typeMap) { |
1338 | if (t.tag != CLASS) return; |
1339 | if (typesSkip.get(t.tsym) != null) return; |
1340 | if (typeMap.put(t.tsym, t) == null) { |
1341 | closure(types.supertype(t), typesSkip, typeMap); |
1342 | for (Type i : types.interfaces(t)) |
1343 | closure(i, typesSkip, typeMap); |
1344 | } |
1345 | } |
1346 | |
1347 | /** Return the first method in t2 that conflicts with a method from t1. */ |
1348 | private Symbol firstDirectIncompatibility(Type t1, Type t2, Type site) { |
1349 | for (Scope.Entry e1 = t1.tsym.members().elems; e1 != null; e1 = e1.sibling) { |
1350 | Symbol s1 = e1.sym; |
1351 | Type st1 = null; |
1352 | if (s1.kind != MTH || !s1.isInheritedIn(site.tsym, types)) continue; |
1353 | Symbol impl = ((MethodSymbol)s1).implementation(site.tsym, types, false); |
1354 | if (impl != null && (impl.flags() & ABSTRACT) == 0) continue; |
1355 | for (Scope.Entry e2 = t2.tsym.members().lookup(s1.name); e2.scope != null; e2 = e2.next()) { |
1356 | Symbol s2 = e2.sym; |
1357 | if (s1 == s2) continue; |
1358 | if (s2.kind != MTH || !s2.isInheritedIn(site.tsym, types)) continue; |
1359 | if (st1 == null) st1 = types.memberType(t1, s1); |
1360 | Type st2 = types.memberType(t2, s2); |
1361 | if (types.overrideEquivalent(st1, st2)) { |
1362 | List<Type> tvars1 = st1.getTypeArguments(); |
1363 | List<Type> tvars2 = st2.getTypeArguments(); |
1364 | Type rt1 = st1.getReturnType(); |
1365 | Type rt2 = types.subst(st2.getReturnType(), tvars2, tvars1); |
1366 | boolean compat = |
1367 | types.isSameType(rt1, rt2) || |
1368 | rt1.tag >= CLASS && rt2.tag >= CLASS && |
1369 | (types.covariantReturnType(rt1, rt2, Warner.noWarnings) || |
1370 | types.covariantReturnType(rt2, rt1, Warner.noWarnings)); |
1371 | if (!compat) return s2; |
1372 | } |
1373 | } |
1374 | } |
1375 | return null; |
1376 | } |
1377 | |
1378 | /** Check that a given method conforms with any method it overrides. |
1379 | * @param tree The tree from which positions are extracted |
1380 | * for errors. |
1381 | * @param m The overriding method. |
1382 | */ |
1383 | void checkOverride(JCTree tree, MethodSymbol m) { |
1384 | ClassSymbol origin = (ClassSymbol)m.owner; |
1385 | if ((origin.flags() & ENUM) != 0 && names.finalize.equals(m.name)) |
1386 | if (m.overrides(syms.enumFinalFinalize, origin, types, false)) { |
1387 | log.error(tree.pos(), "enum.no.finalize"); |
1388 | return; |
1389 | } |
1390 | for (Type t = types.supertype(origin.type); t.tag == CLASS; |
1391 | t = types.supertype(t)) { |
1392 | TypeSymbol c = t.tsym; |
1393 | Scope.Entry e = c.members().lookup(m.name); |
1394 | while (e.scope != null) { |
1395 | if (m.overrides(e.sym, origin, types, false)) |
1396 | checkOverride(tree, m, (MethodSymbol)e.sym, origin); |
1397 | e = e.next(); |
1398 | } |
1399 | } |
1400 | } |
1401 | |
1402 | /** Check that all abstract members of given class have definitions. |
1403 | * @param pos Position to be used for error reporting. |
1404 | * @param c The class. |
1405 | */ |
1406 | void checkAllDefined(DiagnosticPosition pos, ClassSymbol c) { |
1407 | try { |
1408 | MethodSymbol undef = firstUndef(c, c); |
1409 | if (undef != null) { |
1410 | if ((c.flags() & ENUM) != 0 && |
1411 | types.supertype(c.type).tsym == syms.enumSym && |
1412 | (c.flags() & FINAL) == 0) { |
1413 | // add the ABSTRACT flag to an enum |
1414 | c.flags_field |= ABSTRACT; |
1415 | } else { |
1416 | MethodSymbol undef1 = |
1417 | new MethodSymbol(undef.flags(), undef.name, |
1418 | types.memberType(c.type, undef), undef.owner); |
1419 | log.error(pos, "does.not.override.abstract", |
1420 | c, undef1, undef1.location()); |
1421 | } |
1422 | } |
1423 | } catch (CompletionFailure ex) { |
1424 | completionError(pos, ex); |
1425 | } |
1426 | } |
1427 | //where |
1428 | /** Return first abstract member of class `c' that is not defined |
1429 | * in `impl', null if there is none. |
1430 | */ |
1431 | private MethodSymbol firstUndef(ClassSymbol impl, ClassSymbol c) { |
1432 | MethodSymbol undef = null; |
1433 | // Do not bother to search in classes that are not abstract, |
1434 | // since they cannot have abstract members. |
1435 | if (c == impl || (c.flags() & (ABSTRACT | INTERFACE)) != 0) { |
1436 | Scope s = c.members(); |
1437 | for (Scope.Entry e = s.elems; |
1438 | undef == null && e != null; |
1439 | e = e.sibling) { |
1440 | if (e.sym.kind == MTH && |
1441 | (e.sym.flags() & (ABSTRACT|IPROXY)) == ABSTRACT) { |
1442 | MethodSymbol absmeth = (MethodSymbol)e.sym; |
1443 | MethodSymbol implmeth = absmeth.implementation(impl, types, true); |
1444 | if (implmeth == null || implmeth == absmeth) |
1445 | undef = absmeth; |
1446 | } |
1447 | } |
1448 | if (undef == null) { |
1449 | Type st = types.supertype(c.type); |
1450 | if (st.tag == CLASS) |
1451 | undef = firstUndef(impl, (ClassSymbol)st.tsym); |
1452 | } |
1453 | for (List<Type> l = types.interfaces(c.type); |
1454 | undef == null && l.nonEmpty(); |
1455 | l = l.tail) { |
1456 | undef = firstUndef(impl, (ClassSymbol)l.head.tsym); |
1457 | } |
1458 | } |
1459 | return undef; |
1460 | } |
1461 | |
1462 | /** Check for cyclic references. Issue an error if the |
1463 | * symbol of the type referred to has a LOCKED flag set. |
1464 | * |
1465 | * @param pos Position to be used for error reporting. |
1466 | * @param t The type referred to. |
1467 | */ |
1468 | void checkNonCyclic(DiagnosticPosition pos, Type t) { |
1469 | checkNonCyclicInternal(pos, t); |
1470 | } |
1471 | |
1472 | |
1473 | void checkNonCyclic(DiagnosticPosition pos, TypeVar t) { |
1474 | checkNonCyclic1(pos, t, new HashSet<TypeVar>()); |
1475 | } |
1476 | |
1477 | private void checkNonCyclic1(DiagnosticPosition pos, Type t, Set<TypeVar> seen) { |
1478 | final TypeVar tv; |
1479 | if (seen.contains(t)) { |
1480 | tv = (TypeVar)t; |
1481 | tv.bound = new ErrorType(); |
1482 | log.error(pos, "cyclic.inheritance", t); |
1483 | } else if (t.tag == TYPEVAR) { |
1484 | tv = (TypeVar)t; |
1485 | seen.add(tv); |
1486 | for (Type b : types.getBounds(tv)) |
1487 | checkNonCyclic1(pos, b, seen); |
1488 | } |
1489 | } |
1490 | |
1491 | /** Check for cyclic references. Issue an error if the |
1492 | * symbol of the type referred to has a LOCKED flag set. |
1493 | * |
1494 | * @param pos Position to be used for error reporting. |
1495 | * @param t The type referred to. |
1496 | * @returns True if the check completed on all attributed classes |
1497 | */ |
1498 | private boolean checkNonCyclicInternal(DiagnosticPosition pos, Type t) { |
1499 | boolean complete = true; // was the check complete? |
1500 | //- System.err.println("checkNonCyclicInternal("+t+");");//DEBUG |
1501 | Symbol c = t.tsym; |
1502 | if ((c.flags_field & ACYCLIC) != 0) return true; |
1503 | |
1504 | if ((c.flags_field & LOCKED) != 0) { |
1505 | noteCyclic(pos, (ClassSymbol)c); |
1506 | } else if (!c.type.isErroneous()) { |
1507 | try { |
1508 | c.flags_field |= LOCKED; |
1509 | if (c.type.tag == CLASS) { |
1510 | ClassType clazz = (ClassType)c.type; |
1511 | if (clazz.interfaces_field != null) |
1512 | for (List<Type> l=clazz.interfaces_field; l.nonEmpty(); l=l.tail) |
1513 | complete &= checkNonCyclicInternal(pos, l.head); |
1514 | if (clazz.supertype_field != null) { |
1515 | Type st = clazz.supertype_field; |
1516 | if (st != null && st.tag == CLASS) |
1517 | complete &= checkNonCyclicInternal(pos, st); |
1518 | } |
1519 | if (c.owner.kind == TYP) |
1520 | complete &= checkNonCyclicInternal(pos, c.owner.type); |
1521 | } |
1522 | } finally { |
1523 | c.flags_field &= ~LOCKED; |
1524 | } |
1525 | } |
1526 | if (complete) |
1527 | complete = ((c.flags_field & UNATTRIBUTED) == 0) && c.completer == null; |
1528 | if (complete) c.flags_field |= ACYCLIC; |
1529 | return complete; |
1530 | } |
1531 | |
1532 | /** Note that we found an inheritance cycle. */ |
1533 | private void noteCyclic(DiagnosticPosition pos, ClassSymbol c) { |
1534 | log.error(pos, "cyclic.inheritance", c); |
1535 | for (List<Type> l=types.interfaces(c.type); l.nonEmpty(); l=l.tail) |
1536 | l.head = new ErrorType((ClassSymbol)l.head.tsym); |
1537 | Type st = types.supertype(c.type); |
1538 | if (st.tag == CLASS) |
1539 | ((ClassType)c.type).supertype_field = new ErrorType((ClassSymbol)st.tsym); |
1540 | c.type = new ErrorType(c); |
1541 | c.flags_field |= ACYCLIC; |
1542 | } |
1543 | |
1544 | /** Check that all methods which implement some |
1545 | * method conform to the method they implement. |
1546 | * @param tree The class definition whose members are checked. |
1547 | */ |
1548 | void checkImplementations(JCClassDecl tree) { |
1549 | checkImplementations(tree, tree.sym); |
1550 | } |
1551 | //where |
1552 | /** Check that all methods which implement some |
1553 | * method in `ic' conform to the method they implement. |
1554 | */ |
1555 | void checkImplementations(JCClassDecl tree, ClassSymbol ic) { |
1556 | ClassSymbol origin = tree.sym; |
1557 | for (List<Type> l = types.closure(ic.type); l.nonEmpty(); l = l.tail) { |
1558 | ClassSymbol lc = (ClassSymbol)l.head.tsym; |
1559 | if ((allowGenerics || origin != lc) && (lc.flags() & ABSTRACT) != 0) { |
1560 | for (Scope.Entry e=lc.members().elems; e != null; e=e.sibling) { |
1561 | if (e.sym.kind == MTH && |
1562 | (e.sym.flags() & (STATIC|ABSTRACT)) == ABSTRACT) { |
1563 | MethodSymbol absmeth = (MethodSymbol)e.sym; |
1564 | MethodSymbol implmeth = absmeth.implementation(origin, types, false); |
1565 | if (implmeth != null && implmeth != absmeth && |
1566 | (implmeth.owner.flags() & INTERFACE) == |
1567 | (origin.flags() & INTERFACE)) { |
1568 | // don't check if implmeth is in a class, yet |
1569 | // origin is an interface. This case arises only |
1570 | // if implmeth is declared in Object. The reason is |
1571 | // that interfaces really don't inherit from |
1572 | // Object it's just that the compiler represents |
1573 | // things that way. |
1574 | checkOverride(tree, implmeth, absmeth, origin); |
1575 | } |
1576 | } |
1577 | } |
1578 | } |
1579 | } |
1580 | } |
1581 | |
1582 | /** Check that all abstract methods implemented by a class are |
1583 | * mutually compatible. |
1584 | * @param pos Position to be used for error reporting. |
1585 | * @param c The class whose interfaces are checked. |
1586 | */ |
1587 | void checkCompatibleSupertypes(DiagnosticPosition pos, Type c) { |
1588 | List<Type> supertypes = types.interfaces(c); |
1589 | Type supertype = types.supertype(c); |
1590 | if (supertype.tag == CLASS && |
1591 | (supertype.tsym.flags() & ABSTRACT) != 0) |
1592 | supertypes = supertypes.prepend(supertype); |
1593 | for (List<Type> l = supertypes; l.nonEmpty(); l = l.tail) { |
1594 | if (allowGenerics && !l.head.getTypeArguments().isEmpty() && |
1595 | !checkCompatibleAbstracts(pos, l.head, l.head, c)) |
1596 | return; |
1597 | for (List<Type> m = supertypes; m != l; m = m.tail) |
1598 | if (!checkCompatibleAbstracts(pos, l.head, m.head, c)) |
1599 | return; |
1600 | } |
1601 | checkCompatibleConcretes(pos, c); |
1602 | } |
1603 | |
1604 | /** Check that class c does not implement directly or indirectly |
1605 | * the same parameterized interface with two different argument lists. |
1606 | * @param pos Position to be used for error reporting. |
1607 | * @param type The type whose interfaces are checked. |
1608 | */ |
1609 | void checkClassBounds(DiagnosticPosition pos, Type type) { |
1610 | checkClassBounds(pos, new HashMap<TypeSymbol,Type>(), type); |
1611 | } |
1612 | //where |
1613 | /** Enter all interfaces of type `type' into the hash table `seensofar' |
1614 | * with their class symbol as key and their type as value. Make |
1615 | * sure no class is entered with two different types. |
1616 | */ |
1617 | void checkClassBounds(DiagnosticPosition pos, |
1618 | Map<TypeSymbol,Type> seensofar, |
1619 | Type type) { |
1620 | if (type.isErroneous()) return; |
1621 | for (List<Type> l = types.interfaces(type); l.nonEmpty(); l = l.tail) { |
1622 | Type it = l.head; |
1623 | Type oldit = seensofar.put(it.tsym, it); |
1624 | if (oldit != null) { |
1625 | List<Type> oldparams = oldit.allparams(); |
1626 | List<Type> newparams = it.allparams(); |
1627 | if (!types.containsTypeEquivalent(oldparams, newparams)) |
1628 | log.error(pos, "cant.inherit.diff.arg", |
1629 | it.tsym, Type.toString(oldparams), |
1630 | Type.toString(newparams)); |
1631 | } |
1632 | checkClassBounds(pos, seensofar, it); |
1633 | } |
1634 | Type st = types.supertype(type); |
1635 | if (st != null) checkClassBounds(pos, seensofar, st); |
1636 | } |
1637 | |
1638 | /** Enter interface into into set. |
1639 | * If it existed already, issue a "repeated interface" error. |
1640 | */ |
1641 | void checkNotRepeated(DiagnosticPosition pos, Type it, Set<Type> its) { |
1642 | if (its.contains(it)) |
1643 | log.error(pos, "repeated.interface"); |
1644 | else { |
1645 | its.add(it); |
1646 | } |
1647 | } |
1648 | |
1649 | /* ************************************************************************* |
1650 | * Check annotations |
1651 | **************************************************************************/ |
1652 | |
1653 | /** Annotation types are restricted to primitives, String, an |
1654 | * enum, an annotation, Class, Class<?>, Class<? extends |
1655 | * Anything>, arrays of the preceding. |
1656 | */ |
1657 | void validateAnnotationType(JCTree restype) { |
1658 | // restype may be null if an error occurred, so don't bother validating it |
1659 | if (restype != null) { |
1660 | validateAnnotationType(restype.pos(), restype.type); |
1661 | } |
1662 | } |
1663 | |
1664 | void validateAnnotationType(DiagnosticPosition pos, Type type) { |
1665 | if (type.isPrimitive()) return; |
1666 | if (types.isSameType(type, syms.stringType)) return; |
1667 | if ((type.tsym.flags() & Flags.ENUM) != 0) return; |
1668 | if ((type.tsym.flags() & Flags.ANNOTATION) != 0) return; |
1669 | if (types.lowerBound(type).tsym == syms.classType.tsym) return; |
1670 | if (types.isArray(type) && !types.isArray(types.elemtype(type))) { |
1671 | validateAnnotationType(pos, types.elemtype(type)); |
1672 | return; |
1673 | } |
1674 | log.error(pos, "invalid.annotation.member.type"); |
1675 | } |
1676 | |
1677 | /** |
1678 | * "It is also a compile-time error if any method declared in an |
1679 | * annotation type has a signature that is override-equivalent to |
1680 | * that of any public or protected method declared in class Object |
1681 | * or in the interface annotation.Annotation." |
1682 | * |
1683 | * @jls3 9.6 Annotation Types |
1684 | */ |
1685 | void validateAnnotationMethod(DiagnosticPosition pos, MethodSymbol m) { |
1686 | for (Type sup = syms.annotationType; sup.tag == CLASS; sup = types.supertype(sup)) { |
1687 | Scope s = sup.tsym.members(); |
1688 | for (Scope.Entry e = s.lookup(m.name); e.scope != null; e = e.next()) { |
1689 | if (e.sym.kind == MTH && |
1690 | (e.sym.flags() & (PUBLIC | PROTECTED)) != 0 && |
1691 | types.overrideEquivalent(m.type, e.sym.type)) |
1692 | log.error(pos, "intf.annotation.member.clash", e.sym, sup); |
1693 | } |
1694 | } |
1695 | } |
1696 | |
1697 | /** Check the annotations of a symbol. |
1698 | */ |
1699 | public void validateAnnotations(List<JCAnnotation> annotations, Symbol s) { |
1700 | if (skipAnnotations) return; |
1701 | for (JCAnnotation a : annotations) |
1702 | validateAnnotation(a, s); |
1703 | } |
1704 | |
1705 | /** Check an annotation of a symbol. |
1706 | */ |
1707 | public void validateAnnotation(JCAnnotation a, Symbol s) { |
1708 | validateAnnotation(a); |
1709 | |
1710 | if (!annotationApplicable(a, s)) |
1711 | log.error(a.pos(), "annotation.type.not.applicable"); |
1712 | |
1713 | if (a.annotationType.type.tsym == syms.overrideType.tsym) { |
1714 | if (!isOverrider(s)) |
1715 | log.error(a.pos(), "method.does.not.override.superclass"); |
1716 | } |
1717 | } |
1718 | |
1719 | /** Is s a method symbol that overrides a method in a superclass? */ |
1720 | boolean isOverrider(Symbol s) { |
1721 | if (s.kind != MTH || s.isStatic()) |
1722 | return false; |
1723 | MethodSymbol m = (MethodSymbol)s; |
1724 | TypeSymbol owner = (TypeSymbol)m.owner; |
1725 | for (Type sup : types.closure(owner.type)) { |
1726 | if (sup == owner.type) |
1727 | continue; // skip "this" |
1728 | Scope scope = sup.tsym.members(); |
1729 | for (Scope.Entry e = scope.lookup(m.name); e.scope != null; e = e.next()) { |
1730 | if (!e.sym.isStatic() && m.overrides(e.sym, owner, types, true)) |
1731 | return true; |
1732 | } |
1733 | } |
1734 | return false; |
1735 | } |
1736 | |
1737 | /** Is the annotation applicable to the symbol? */ |
1738 | boolean annotationApplicable(JCAnnotation a, Symbol s) { |
1739 | Attribute.Compound atTarget = |
1740 | a.annotationType.type.tsym.attribute(syms.annotationTargetType.tsym); |
1741 | if (atTarget == null) return true; |
1742 | Attribute atValue = atTarget.member(names.value); |
1743 | if (!(atValue instanceof Attribute.Array)) return true; // error recovery |
1744 | Attribute.Array arr = (Attribute.Array) atValue; |
1745 | for (Attribute app : arr.values) { |
1746 | if (!(app instanceof Attribute.Enum)) return true; // recovery |
1747 | Attribute.Enum e = (Attribute.Enum) app; |
1748 | if (e.value.name == names.TYPE) |
1749 | { if (s.kind == TYP) return true; } |
1750 | else if (e.value.name == names.FIELD) |
1751 | { if (s.kind == VAR && s.owner.kind != MTH) return true; } |
1752 | else if (e.value.name == names.METHOD) |
1753 | { if (s.kind == MTH && !s.isConstructor()) return true; } |
1754 | else if (e.value.name == names.PARAMETER) |
1755 | { if (s.kind == VAR && |
1756 | s.owner.kind == MTH && |
1757 | (s.flags() & PARAMETER) != 0) |
1758 | return true; |
1759 | } |
1760 | else if (e.value.name == names.CONSTRUCTOR) |
1761 | { if (s.kind == MTH && s.isConstructor()) return true; } |
1762 | else if (e.value.name == names.LOCAL_VARIABLE) |
1763 | { if (s.kind == VAR && s.owner.kind == MTH && |
1764 | (s.flags() & PARAMETER) == 0) |
1765 | return true; |
1766 | } |
1767 | else if (e.value.name == names.ANNOTATION_TYPE) |
1768 | { if (s.kind == TYP && (s.flags() & ANNOTATION) != 0) |
1769 | return true; |
1770 | } |
1771 | else if (e.value.name == names.PACKAGE) |
1772 | { if (s.kind == PCK) return true; } |
1773 | else |
1774 | return true; // recovery |
1775 | } |
1776 | return false; |
1777 | } |
1778 | |
1779 | /** Check an annotation value. |
1780 | */ |
1781 | public void validateAnnotation(JCAnnotation a) { |
1782 | if (a.type.isErroneous()) return; |
1783 | |
1784 | // collect an inventory of the members |
1785 | Set<MethodSymbol> members = new HashSet<MethodSymbol>(); |
1786 | for (Scope.Entry e = a.annotationType.type.tsym.members().elems; |
1787 | e != null; |
1788 | e = e.sibling) |
1789 | if (e.sym.kind == MTH) |
1790 | members.add((MethodSymbol) e.sym); |
1791 | |
1792 | // count them off as they're annotated |
1793 | for (JCTree arg : a.args) { |
1794 | if (arg.getTag() != JCTree.ASSIGN) continue; // recovery |
1795 | JCAssign assign = (JCAssign) arg; |
1796 | Symbol m = TreeInfo.symbol(assign.lhs); |
1797 | if (m == null || m.type.isErroneous()) continue; |
1798 | if (!members.remove(m)) |
1799 | log.error(arg.pos(), "duplicate.annotation.member.value", |
1800 | m.name, a.type); |
1801 | if (assign.rhs.getTag() == ANNOTATION) |
1802 | validateAnnotation((JCAnnotation)assign.rhs); |
1803 | } |
1804 | |
1805 | // all the remaining ones better have default values |
1806 | for (MethodSymbol m : members) |
1807 | if (m.defaultValue == null && !m.type.isErroneous()) |
1808 | log.error(a.pos(), "annotation.missing.default.value", |
1809 | a.type, m.name); |
1810 | |
1811 | // special case: java.lang.annotation.Target must not have |
1812 | // repeated values in its value member |
1813 | if (a.annotationType.type.tsym != syms.annotationTargetType.tsym || |
1814 | a.args.tail == null) |
1815 | return; |
1816 | |
1817 | if (a.args.head.getTag() != JCTree.ASSIGN) return; // error recovery |
1818 | JCAssign assign = (JCAssign) a.args.head; |
1819 | Symbol m = TreeInfo.symbol(assign.lhs); |
1820 | if (m.name != names.value) return; |
1821 | JCTree rhs = assign.rhs; |
1822 | if (rhs.getTag() != JCTree.NEWARRAY) return; |
1823 | JCNewArray na = (JCNewArray) rhs; |
1824 | Set<Symbol> targets = new HashSet<Symbol>(); |
1825 | for (JCTree elem : na.elems) { |
1826 | if (!targets.add(TreeInfo.symbol(elem))) { |
1827 | log.error(elem.pos(), "repeated.annotation.target"); |
1828 | } |
1829 | } |
1830 | } |
1831 | |
1832 | void checkDeprecatedAnnotation(DiagnosticPosition pos, Symbol s) { |
1833 | if (allowAnnotations && |
1834 | lint.isEnabled(Lint.LintCategory.DEP_ANN) && |
1835 | (s.flags() & DEPRECATED) != 0 && |
1836 | !syms.deprecatedType.isErroneous() && |
1837 | s.attribute(syms.deprecatedType.tsym) == null) { |
1838 | log.warning(pos, "missing.deprecated.annotation"); |
1839 | } |
1840 | } |
1841 | |
1842 | /* ************************************************************************* |
1843 | * Check for recursive annotation elements. |
1844 | **************************************************************************/ |
1845 | |
1846 | /** Check for cycles in the graph of annotation elements. |
1847 | */ |
1848 | void checkNonCyclicElements(JCClassDecl tree) { |
1849 | if ((tree.sym.flags_field & ANNOTATION) == 0) return; |
1850 | assert (tree.sym.flags_field & LOCKED) == 0; |
1851 | try { |
1852 | tree.sym.flags_field |= LOCKED; |
1853 | for (JCTree def : tree.defs) { |
1854 | if (def.getTag() != JCTree.METHODDEF) continue; |
1855 | JCMethodDecl meth = (JCMethodDecl)def; |
1856 | checkAnnotationResType(meth.pos(), meth.restype.type); |
1857 | } |
1858 | } finally { |
1859 | tree.sym.flags_field &= ~LOCKED; |
1860 | tree.sym.flags_field |= ACYCLIC_ANN; |
1861 | } |
1862 | } |
1863 | |
1864 | void checkNonCyclicElementsInternal(DiagnosticPosition pos, TypeSymbol tsym) { |
1865 | if ((tsym.flags_field & ACYCLIC_ANN) != 0) |
1866 | return; |
1867 | if ((tsym.flags_field & LOCKED) != 0) { |
1868 | log.error(pos, "cyclic.annotation.element"); |
1869 | return; |
1870 | } |
1871 | try { |
1872 | tsym.flags_field |= LOCKED; |
1873 | for (Scope.Entry e = tsym.members().elems; e != null; e = e.sibling) { |
1874 | Symbol s = e.sym; |
1875 | if (s.kind != Kinds.MTH) |
1876 | continue; |
1877 | checkAnnotationResType(pos, ((MethodSymbol)s).type.getReturnType()); |
1878 | } |
1879 | } finally { |
1880 | tsym.flags_field &= ~LOCKED; |
1881 | tsym.flags_field |= ACYCLIC_ANN; |
1882 | } |
1883 | } |
1884 | |
1885 | void checkAnnotationResType(DiagnosticPosition pos, Type type) { |
1886 | switch (type.tag) { |
1887 | case TypeTags.CLASS: |
1888 | if ((type.tsym.flags() & ANNOTATION) != 0) |
1889 | checkNonCyclicElementsInternal(pos, type.tsym); |
1890 | break; |
1891 | case TypeTags.ARRAY: |
1892 | checkAnnotationResType(pos, types.elemtype(type)); |
1893 | break; |
1894 | default: |
1895 | break; // int etc |
1896 | } |
1897 | } |
1898 | |
1899 | /* ************************************************************************* |
1900 | * Check for cycles in the constructor call graph. |
1901 | **************************************************************************/ |
1902 | |
1903 | /** Check for cycles in the graph of constructors calling other |
1904 | * constructors. |
1905 | */ |
1906 | void checkCyclicConstructors(JCClassDecl tree) { |
1907 | Map<Symbol,Symbol> callMap = new HashMap<Symbol, Symbol>(); |
1908 | |
1909 | // enter each constructor this-call into the map |
1910 | for (List<JCTree> l = tree.defs; l.nonEmpty(); l = l.tail) { |
1911 | JCMethodInvocation app = TreeInfo.firstConstructorCall(l.head); |
1912 | if (app == null) continue; |
1913 | JCMethodDecl meth = (JCMethodDecl) l.head; |
1914 | if (TreeInfo.name(app.meth) == names._this) { |
1915 | callMap.put(meth.sym, TreeInfo.symbol(app.meth)); |
1916 | } else { |
1917 | meth.sym.flags_field |= ACYCLIC; |
1918 | } |
1919 | } |
1920 | |
1921 | // Check for cycles in the map |
1922 | Symbol[] ctors = new Symbol[0]; |
1923 | ctors = callMap.keySet().toArray(ctors); |
1924 | for (Symbol caller : ctors) { |
1925 | checkCyclicConstructor(tree, caller, callMap); |
1926 | } |
1927 | } |
1928 | |
1929 | /** Look in the map to see if the given constructor is part of a |
1930 | * call cycle. |
1931 | */ |
1932 | private void checkCyclicConstructor(JCClassDecl tree, Symbol ctor, |
1933 | Map<Symbol,Symbol> callMap) { |
1934 | if (ctor != null && (ctor.flags_field & ACYCLIC) == 0) { |
1935 | if ((ctor.flags_field & LOCKED) != 0) { |
1936 | log.error(TreeInfo.diagnosticPositionFor(ctor, tree), |
1937 | "recursive.ctor.invocation"); |
1938 | } else { |
1939 | ctor.flags_field |= LOCKED; |
1940 | checkCyclicConstructor(tree, callMap.remove(ctor), callMap); |
1941 | ctor.flags_field &= ~LOCKED; |
1942 | } |
1943 | ctor.flags_field |= ACYCLIC; |
1944 | } |
1945 | } |
1946 | |
1947 | /* ************************************************************************* |
1948 | * Miscellaneous |
1949 | **************************************************************************/ |
1950 | |
1951 | /** |
1952 | * Return the opcode of the operator but emit an error if it is an |
1953 | * error. |
1954 | * @param pos position for error reporting. |
1955 | * @param operator an operator |
1956 | * @param tag a tree tag |
1957 | * @param left type of left hand side |
1958 | * @param right type of right hand side |
1959 | */ |
1960 | int checkOperator(DiagnosticPosition pos, |
1961 | OperatorSymbol operator, |
1962 | int tag, |
1963 | Type left, |
1964 | Type right) { |
1965 | if (operator.opcode == ByteCodes.error) { |
1966 | log.error(pos, |
1967 | "operator.cant.be.applied", |
1968 | treeinfo.operatorName(tag), |
1969 | left + "," + right); |
1970 | } |
1971 | return operator.opcode; |
1972 | } |
1973 | |
1974 | |
1975 | /** |
1976 | * Check for division by integer constant zero |
1977 | * @param pos Position for error reporting. |
1978 | * @param operator The operator for the expression |
1979 | * @param operand The right hand operand for the expression |
1980 | */ |
1981 | void checkDivZero(DiagnosticPosition pos, Symbol operator, Type operand) { |
1982 | if (operand.constValue() != null |
1983 | && lint.isEnabled(Lint.LintCategory.DIVZERO) |
1984 | && operand.tag <= LONG |
1985 | && ((Number) (operand.constValue())).longValue() == 0) { |
1986 | int opc = ((OperatorSymbol)operator).opcode; |
1987 | if (opc == ByteCodes.idiv || opc == ByteCodes.imod |
1988 | || opc == ByteCodes.ldiv || opc == ByteCodes.lmod) { |
1989 | log.warning(pos, "div.zero"); |
1990 | } |
1991 | } |
1992 | } |
1993 | |
1994 | /** |
1995 | * Check for empty statements after if |
1996 | */ |
1997 | void checkEmptyIf(JCIf tree) { |
1998 | if (tree.thenpart.getTag() == JCTree.SKIP && tree.elsepart == null && lint.isEnabled(Lint.LintCategory.EMPTY)) |
1999 | log.warning(tree.thenpart.pos(), "empty.if"); |
2000 | } |
2001 | |
2002 | /** Check that symbol is unique in given scope. |
2003 | * @param pos Position for error reporting. |
2004 | * @param sym The symbol. |
2005 | * @param s The scope. |
2006 | */ |
2007 | boolean checkUnique(DiagnosticPosition pos, Symbol sym, Scope s) { |
2008 | if (sym.type.isErroneous()) |
2009 | return true; |
2010 | if (sym.owner.name == names.any) return false; |
2011 | for (Scope.Entry e = s.lookup(sym.name); e.scope == s; e = e.next()) { |
2012 | if (sym != e.sym && |
2013 | sym.kind == e.sym.kind && |
2014 | sym.name != names.error && |
2015 | (sym.kind != MTH || types.overrideEquivalent(sym.type, e.sym.type))) { |
2016 | if ((sym.flags() & VARARGS) != (e.sym.flags() & VARARGS)) |
2017 | varargsDuplicateError(pos, sym, e.sym); |
2018 | else |
2019 | duplicateError(pos, e.sym); |
2020 | return false; |
2021 | } |
2022 | } |
2023 | return true; |
2024 | } |
2025 | |
2026 | /** Check that single-type import is not already imported or top-level defined, |
2027 | * but make an exception for two single-type imports which denote the same type. |
2028 | * @param pos Position for error reporting. |
2029 | * @param sym The symbol. |
2030 | * @param s The scope |
2031 | */ |
2032 | boolean checkUniqueImport(DiagnosticPosition pos, Symbol sym, Scope s) { |
2033 | return checkUniqueImport(pos, sym, s, false); |
2034 | } |
2035 | |
2036 | /** Check that static single-type import is not already imported or top-level defined, |
2037 | * but make an exception for two single-type imports which denote the same type. |
2038 | * @param pos Position for error reporting. |
2039 | * @param sym The symbol. |
2040 | * @param s The scope |
2041 | * @param staticImport Whether or not this was a static import |
2042 | */ |
2043 | boolean checkUniqueStaticImport(DiagnosticPosition pos, Symbol sym, Scope s) { |
2044 | return checkUniqueImport(pos, sym, s, true); |
2045 | } |
2046 | |
2047 | /** Check that single-type import is not already imported or top-level defined, |
2048 | * but make an exception for two single-type imports which denote the same type. |
2049 | * @param pos Position for error reporting. |
2050 | * @param sym The symbol. |
2051 | * @param s The scope. |
2052 | * @param staticImport Whether or not this was a static import |
2053 | */ |
2054 | private boolean checkUniqueImport(DiagnosticPosition pos, Symbol sym, Scope s, boolean staticImport) { |
2055 | for (Scope.Entry e = s.lookup(sym.name); e.scope != null; e = e.next()) { |
2056 | // is encountered class entered via a class declaration? |
2057 | boolean isClassDecl = e.scope == s; |
2058 | if ((isClassDecl || sym != e.sym) && |
2059 | sym.kind == e.sym.kind && |
2060 | sym.name != names.error) { |
2061 | if (!e.sym.type.isErroneous()) { |
2062 | String what = e.sym.toString(); |
2063 | if (!isClassDecl) { |
2064 | if (staticImport) |
2065 | log.error(pos, "already.defined.static.single.import", what); |
2066 | else |
2067 | log.error(pos, "already.defined.single.import", what); |
2068 | } |
2069 | else if (sym != e.sym) |
2070 | log.error(pos, "already.defined.this.unit", what); |
2071 | } |
2072 | return false; |
2073 | } |
2074 | } |
2075 | return true; |
2076 | } |
2077 | |
2078 | /** Check that a qualified name is in canonical form (for import decls). |
2079 | */ |
2080 | public void checkCanonical(JCTree tree) { |
2081 | if (!isCanonical(tree)) |
2082 | log.error(tree.pos(), "import.requires.canonical", |
2083 | TreeInfo.symbol(tree)); |
2084 | } |
2085 | // where |
2086 | private boolean isCanonical(JCTree tree) { |
2087 | while (tree.getTag() == JCTree.SELECT) { |
2088 | JCFieldAccess s = (JCFieldAccess) tree; |
2089 | if (s.sym.owner != TreeInfo.symbol(s.selected)) |
2090 | return false; |
2091 | tree = s.selected; |
2092 | } |
2093 | return true; |
2094 | } |
2095 | |
2096 | private class ConversionWarner extends Warner { |
2097 | final String key; |
2098 | final Type found; |
2099 | final Type expected; |
2100 | public ConversionWarner(DiagnosticPosition pos, String key, Type found, Type expected) { |
2101 | super(pos); |
2102 | this.key = key; |
2103 | this.found = found; |
2104 | this.expected = expected; |
2105 | } |
2106 | |
2107 | public void warnUnchecked() { |
2108 | boolean warned = this.warned; |
2109 | super.warnUnchecked(); |
2110 | if (warned) return; // suppress redundant diagnostics |
2111 | Object problem = JCDiagnostic.fragment(key); |
2112 | Check.this.warnUnchecked(pos(), "prob.found.req", problem, found, expected); |
2113 | } |
2114 | } |
2115 | |
2116 | public Warner castWarner(DiagnosticPosition pos, Type found, Type expected) { |
2117 | return new ConversionWarner(pos, "unchecked.cast.to.type", found, expected); |
2118 | } |
2119 | |
2120 | public Warner convertWarner(DiagnosticPosition pos, Type found, Type expected) { |
2121 | return new ConversionWarner(pos, "unchecked.assign", found, expected); |
2122 | } |
2123 | } |