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 | import javax.lang.model.element.ElementKind; |
31 | import javax.tools.JavaFileObject; |
32 | |
33 | import com.sun.tools.javac.code.*; |
34 | import com.sun.tools.javac.jvm.*; |
35 | import com.sun.tools.javac.tree.*; |
36 | import com.sun.tools.javac.util.*; |
37 | import com.sun.tools.javac.util.JCDiagnostic.DiagnosticPosition; |
38 | import com.sun.tools.javac.util.List; |
39 | |
40 | import com.sun.tools.javac.jvm.Target; |
41 | import com.sun.tools.javac.code.Symbol.*; |
42 | import com.sun.tools.javac.tree.JCTree.*; |
43 | import com.sun.tools.javac.code.Type.*; |
44 | |
45 | import com.sun.source.tree.IdentifierTree; |
46 | import com.sun.source.tree.MemberSelectTree; |
47 | import com.sun.source.tree.TreeVisitor; |
48 | import com.sun.source.util.SimpleTreeVisitor; |
49 | |
50 | import static com.sun.tools.javac.code.Flags.*; |
51 | import static com.sun.tools.javac.code.Kinds.*; |
52 | import static com.sun.tools.javac.code.TypeTags.*; |
53 | |
54 | /** This is the main context-dependent analysis phase in GJC. It |
55 | * encompasses name resolution, type checking and constant folding as |
56 | * subtasks. Some subtasks involve auxiliary classes. |
57 | * @see Check |
58 | * @see Resolve |
59 | * @see ConstFold |
60 | * @see Infer |
61 | * |
62 | * <p><b>This is NOT part of any API supported by Sun Microsystems. If |
63 | * you write code that depends on this, you do so at your own risk. |
64 | * This code and its internal interfaces are subject to change or |
65 | * deletion without notice.</b> |
66 | */ |
67 | public class Attr extends JCTree.Visitor { |
68 | protected static final Context.Key<Attr> attrKey = |
69 | new Context.Key<Attr>(); |
70 | |
71 | final Name.Table names; |
72 | final Log log; |
73 | final Symtab syms; |
74 | final Resolve rs; |
75 | final Check chk; |
76 | final MemberEnter memberEnter; |
77 | final TreeMaker make; |
78 | final ConstFold cfolder; |
79 | final Enter enter; |
80 | final Target target; |
81 | final Types types; |
82 | final Annotate annotate; |
83 | |
84 | public static Attr instance(Context context) { |
85 | Attr instance = context.get(attrKey); |
86 | if (instance == null) |
87 | instance = new Attr(context); |
88 | return instance; |
89 | } |
90 | |
91 | protected Attr(Context context) { |
92 | context.put(attrKey, this); |
93 | |
94 | names = Name.Table.instance(context); |
95 | log = Log.instance(context); |
96 | syms = Symtab.instance(context); |
97 | rs = Resolve.instance(context); |
98 | chk = Check.instance(context); |
99 | memberEnter = MemberEnter.instance(context); |
100 | make = TreeMaker.instance(context); |
101 | enter = Enter.instance(context); |
102 | cfolder = ConstFold.instance(context); |
103 | target = Target.instance(context); |
104 | types = Types.instance(context); |
105 | annotate = Annotate.instance(context); |
106 | |
107 | Options options = Options.instance(context); |
108 | |
109 | Source source = Source.instance(context); |
110 | allowGenerics = source.allowGenerics(); |
111 | allowVarargs = source.allowVarargs(); |
112 | allowEnums = source.allowEnums(); |
113 | allowBoxing = source.allowBoxing(); |
114 | allowCovariantReturns = source.allowCovariantReturns(); |
115 | allowAnonOuterThis = source.allowAnonOuterThis(); |
116 | relax = (options.get("-retrofit") != null || |
117 | options.get("-relax") != null); |
118 | useBeforeDeclarationWarning = options.get("useBeforeDeclarationWarning") != null; |
119 | } |
120 | |
121 | /** Switch: relax some constraints for retrofit mode. |
122 | */ |
123 | boolean relax; |
124 | |
125 | /** Switch: support generics? |
126 | */ |
127 | boolean allowGenerics; |
128 | |
129 | /** Switch: allow variable-arity methods. |
130 | */ |
131 | boolean allowVarargs; |
132 | |
133 | /** Switch: support enums? |
134 | */ |
135 | boolean allowEnums; |
136 | |
137 | /** Switch: support boxing and unboxing? |
138 | */ |
139 | boolean allowBoxing; |
140 | |
141 | /** Switch: support covariant result types? |
142 | */ |
143 | boolean allowCovariantReturns; |
144 | |
145 | /** Switch: allow references to surrounding object from anonymous |
146 | * objects during constructor call? |
147 | */ |
148 | boolean allowAnonOuterThis; |
149 | |
150 | /** |
151 | * Switch: warn about use of variable before declaration? |
152 | * RFE: 6425594 |
153 | */ |
154 | boolean useBeforeDeclarationWarning; |
155 | |
156 | /** Check kind and type of given tree against protokind and prototype. |
157 | * If check succeeds, store type in tree and return it. |
158 | * If check fails, store errType in tree and return it. |
159 | * No checks are performed if the prototype is a method type. |
160 | * Its not necessary in this case since we know that kind and type |
161 | * are correct. |
162 | * |
163 | * @param tree The tree whose kind and type is checked |
164 | * @param owntype The computed type of the tree |
165 | * @param ownkind The computed kind of the tree |
166 | * @param pkind The expected kind (or: protokind) of the tree |
167 | * @param pt The expected type (or: prototype) of the tree |
168 | */ |
169 | Type check(JCTree tree, Type owntype, int ownkind, int pkind, Type pt) { |
170 | if (owntype.tag != ERROR && pt.tag != METHOD && pt.tag != FORALL) { |
171 | if ((ownkind & ~pkind) == 0) { |
172 | owntype = chk.checkType(tree.pos(), owntype, pt); |
173 | } else { |
174 | log.error(tree.pos(), "unexpected.type", |
175 | Resolve.kindNames(pkind), |
176 | Resolve.kindName(ownkind)); |
177 | owntype = syms.errType; |
178 | } |
179 | } |
180 | tree.type = owntype; |
181 | return owntype; |
182 | } |
183 | |
184 | /** Is given blank final variable assignable, i.e. in a scope where it |
185 | * may be assigned to even though it is final? |
186 | * @param v The blank final variable. |
187 | * @param env The current environment. |
188 | */ |
189 | boolean isAssignableAsBlankFinal(VarSymbol v, Env<AttrContext> env) { |
190 | Symbol owner = env.info.scope.owner; |
191 | // owner refers to the innermost variable, method or |
192 | // initializer block declaration at this point. |
193 | return |
194 | v.owner == owner |
195 | || |
196 | ((owner.name == names.init || // i.e. we are in a constructor |
197 | owner.kind == VAR || // i.e. we are in a variable initializer |
198 | (owner.flags() & BLOCK) != 0) // i.e. we are in an initializer block |
199 | && |
200 | v.owner == owner.owner |
201 | && |
202 | ((v.flags() & STATIC) != 0) == Resolve.isStatic(env)); |
203 | } |
204 | |
205 | /** Check that variable can be assigned to. |
206 | * @param pos The current source code position. |
207 | * @param v The assigned varaible |
208 | * @param base If the variable is referred to in a Select, the part |
209 | * to the left of the `.', null otherwise. |
210 | * @param env The current environment. |
211 | */ |
212 | void checkAssignable(DiagnosticPosition pos, VarSymbol v, JCTree base, Env<AttrContext> env) { |
213 | if ((v.flags() & FINAL) != 0 && |
214 | ((v.flags() & HASINIT) != 0 |
215 | || |
216 | !((base == null || |
217 | (base.getTag() == JCTree.IDENT && TreeInfo.name(base) == names._this)) && |
218 | isAssignableAsBlankFinal(v, env)))) { |
219 | log.error(pos, "cant.assign.val.to.final.var", v); |
220 | } |
221 | } |
222 | |
223 | /** Does tree represent a static reference to an identifier? |
224 | * It is assumed that tree is either a SELECT or an IDENT. |
225 | * We have to weed out selects from non-type names here. |
226 | * @param tree The candidate tree. |
227 | */ |
228 | boolean isStaticReference(JCTree tree) { |
229 | if (tree.getTag() == JCTree.SELECT) { |
230 | Symbol lsym = TreeInfo.symbol(((JCFieldAccess) tree).selected); |
231 | if (lsym == null || lsym.kind != TYP) { |
232 | return false; |
233 | } |
234 | } |
235 | return true; |
236 | } |
237 | |
238 | /** Is this symbol a type? |
239 | */ |
240 | static boolean isType(Symbol sym) { |
241 | return sym != null && sym.kind == TYP; |
242 | } |
243 | |
244 | /** The current `this' symbol. |
245 | * @param env The current environment. |
246 | */ |
247 | Symbol thisSym(DiagnosticPosition pos, Env<AttrContext> env) { |
248 | return rs.resolveSelf(pos, env, env.enclClass.sym, names._this); |
249 | } |
250 | |
251 | /** Attribute a parsed identifier. |
252 | * @param tree Parsed identifier name |
253 | * @param topLevel The toplevel to use |
254 | */ |
255 | public Symbol attribIdent(JCTree tree, JCCompilationUnit topLevel) { |
256 | Env<AttrContext> localEnv = enter.topLevelEnv(topLevel); |
257 | localEnv.enclClass = make.ClassDef(make.Modifiers(0), |
258 | syms.errSymbol.name, |
259 | null, null, null, null); |
260 | localEnv.enclClass.sym = syms.errSymbol; |
261 | return tree.accept(identAttributer, localEnv); |
262 | } |
263 | // where |
264 | private TreeVisitor<Symbol,Env<AttrContext>> identAttributer = new IdentAttributer(); |
265 | private class IdentAttributer extends SimpleTreeVisitor<Symbol,Env<AttrContext>> { |
266 | @Override |
267 | public Symbol visitMemberSelect(MemberSelectTree node, Env<AttrContext> env) { |
268 | Symbol site = visit(node.getExpression(), env); |
269 | if (site.kind == ERR) |
270 | return site; |
271 | Name name = (Name)node.getIdentifier(); |
272 | if (site.kind == PCK) { |
273 | env.toplevel.packge = (PackageSymbol)site; |
274 | return rs.findIdentInPackage(env, (TypeSymbol)site, name, TYP | PCK); |
275 | } else { |
276 | env.enclClass.sym = (ClassSymbol)site; |
277 | return rs.findMemberType(env, site.asType(), name, (TypeSymbol)site); |
278 | } |
279 | } |
280 | |
281 | @Override |
282 | public Symbol visitIdentifier(IdentifierTree node, Env<AttrContext> env) { |
283 | return rs.findIdent(env, (Name)node.getName(), TYP | PCK); |
284 | } |
285 | } |
286 | |
287 | public Type coerce(Type etype, Type ttype) { |
288 | return cfolder.coerce(etype, ttype); |
289 | } |
290 | |
291 | public Type attribType(JCTree node, TypeSymbol sym) { |
292 | Env<AttrContext> env = enter.typeEnvs.get(sym); |
293 | Env<AttrContext> localEnv = env.dup(node, env.info.dup()); |
294 | return attribTree(node, localEnv, Kinds.TYP, Type.noType); |
295 | } |
296 | |
297 | public Env<AttrContext> attribExprToTree(JCTree expr, Env<AttrContext> env, JCTree tree) { |
298 | breakTree = tree; |
299 | JavaFileObject prev = log.useSource(null); |
300 | try { |
301 | attribExpr(expr, env); |
302 | } catch (BreakAttr b) { |
303 | return b.env; |
304 | } finally { |
305 | breakTree = null; |
306 | log.useSource(prev); |
307 | } |
308 | return env; |
309 | } |
310 | |
311 | public Env<AttrContext> attribStatToTree(JCTree stmt, Env<AttrContext> env, JCTree tree) { |
312 | breakTree = tree; |
313 | JavaFileObject prev = log.useSource(null); |
314 | try { |
315 | attribStat(stmt, env); |
316 | } catch (BreakAttr b) { |
317 | return b.env; |
318 | } finally { |
319 | breakTree = null; |
320 | log.useSource(prev); |
321 | } |
322 | return env; |
323 | } |
324 | |
325 | private JCTree breakTree = null; |
326 | |
327 | private static class BreakAttr extends RuntimeException { |
328 | static final long serialVersionUID = -6924771130405446405L; |
329 | private Env<AttrContext> env; |
330 | private BreakAttr(Env<AttrContext> env) { |
331 | this.env = env; |
332 | } |
333 | } |
334 | |
335 | |
336 | /* ************************************************************************ |
337 | * Visitor methods |
338 | *************************************************************************/ |
339 | |
340 | /** Visitor argument: the current environment. |
341 | */ |
342 | Env<AttrContext> env; |
343 | |
344 | /** Visitor argument: the currently expected proto-kind. |
345 | */ |
346 | int pkind; |
347 | |
348 | /** Visitor argument: the currently expected proto-type. |
349 | */ |
350 | Type pt; |
351 | |
352 | /** Visitor result: the computed type. |
353 | */ |
354 | Type result; |
355 | |
356 | /** Visitor method: attribute a tree, catching any completion failure |
357 | * exceptions. Return the tree's type. |
358 | * |
359 | * @param tree The tree to be visited. |
360 | * @param env The environment visitor argument. |
361 | * @param pkind The protokind visitor argument. |
362 | * @param pt The prototype visitor argument. |
363 | */ |
364 | Type attribTree(JCTree tree, Env<AttrContext> env, int pkind, Type pt) { |
365 | Env<AttrContext> prevEnv = this.env; |
366 | int prevPkind = this.pkind; |
367 | Type prevPt = this.pt; |
368 | try { |
369 | this.env = env; |
370 | this.pkind = pkind; |
371 | this.pt = pt; |
372 | tree.accept(this); |
373 | if (tree == breakTree) |
374 | throw new BreakAttr(env); |
375 | return result; |
376 | } catch (CompletionFailure ex) { |
377 | tree.type = syms.errType; |
378 | return chk.completionError(tree.pos(), ex); |
379 | } finally { |
380 | this.env = prevEnv; |
381 | this.pkind = prevPkind; |
382 | this.pt = prevPt; |
383 | } |
384 | } |
385 | |
386 | /** Derived visitor method: attribute an expression tree. |
387 | */ |
388 | public Type attribExpr(JCTree tree, Env<AttrContext> env, Type pt) { |
389 | return attribTree(tree, env, VAL, pt.tag != ERROR ? pt : Type.noType); |
390 | } |
391 | |
392 | /** Derived visitor method: attribute an expression tree with |
393 | * no constraints on the computed type. |
394 | */ |
395 | Type attribExpr(JCTree tree, Env<AttrContext> env) { |
396 | return attribTree(tree, env, VAL, Type.noType); |
397 | } |
398 | |
399 | /** Derived visitor method: attribute a type tree. |
400 | */ |
401 | Type attribType(JCTree tree, Env<AttrContext> env) { |
402 | Type result = attribTree(tree, env, TYP, Type.noType); |
403 | return result; |
404 | } |
405 | |
406 | /** Derived visitor method: attribute a statement or definition tree. |
407 | */ |
408 | public Type attribStat(JCTree tree, Env<AttrContext> env) { |
409 | return attribTree(tree, env, NIL, Type.noType); |
410 | } |
411 | |
412 | /** Attribute a list of expressions, returning a list of types. |
413 | */ |
414 | List<Type> attribExprs(List<JCExpression> trees, Env<AttrContext> env, Type pt) { |
415 | ListBuffer<Type> ts = new ListBuffer<Type>(); |
416 | for (List<JCExpression> l = trees; l.nonEmpty(); l = l.tail) |
417 | ts.append(attribExpr(l.head, env, pt)); |
418 | return ts.toList(); |
419 | } |
420 | |
421 | /** Attribute a list of statements, returning nothing. |
422 | */ |
423 | <T extends JCTree> void attribStats(List<T> trees, Env<AttrContext> env) { |
424 | for (List<T> l = trees; l.nonEmpty(); l = l.tail) |
425 | attribStat(l.head, env); |
426 | } |
427 | |
428 | /** Attribute the arguments in a method call, returning a list of types. |
429 | */ |
430 | List<Type> attribArgs(List<JCExpression> trees, Env<AttrContext> env) { |
431 | ListBuffer<Type> argtypes = new ListBuffer<Type>(); |
432 | for (List<JCExpression> l = trees; l.nonEmpty(); l = l.tail) |
433 | argtypes.append(chk.checkNonVoid( |
434 | l.head.pos(), types.upperBound(attribTree(l.head, env, VAL, Infer.anyPoly)))); |
435 | return argtypes.toList(); |
436 | } |
437 | |
438 | /** Attribute a type argument list, returning a list of types. |
439 | */ |
440 | List<Type> attribTypes(List<JCExpression> trees, Env<AttrContext> env) { |
441 | ListBuffer<Type> argtypes = new ListBuffer<Type>(); |
442 | for (List<JCExpression> l = trees; l.nonEmpty(); l = l.tail) |
443 | argtypes.append(chk.checkRefType(l.head.pos(), attribType(l.head, env))); |
444 | return argtypes.toList(); |
445 | } |
446 | |
447 | |
448 | /** |
449 | * Attribute type variables (of generic classes or methods). |
450 | * Compound types are attributed later in attribBounds. |
451 | * @param typarams the type variables to enter |
452 | * @param env the current environment |
453 | */ |
454 | void attribTypeVariables(List<JCTypeParameter> typarams, Env<AttrContext> env) { |
455 | for (JCTypeParameter tvar : typarams) { |
456 | TypeVar a = (TypeVar)tvar.type; |
457 | if (!tvar.bounds.isEmpty()) { |
458 | List<Type> bounds = List.of(attribType(tvar.bounds.head, env)); |
459 | for (JCExpression bound : tvar.bounds.tail) |
460 | bounds = bounds.prepend(attribType(bound, env)); |
461 | types.setBounds(a, bounds.reverse()); |
462 | } else { |
463 | // if no bounds are given, assume a single bound of |
464 | // java.lang.Object. |
465 | types.setBounds(a, List.of(syms.objectType)); |
466 | } |
467 | } |
468 | for (JCTypeParameter tvar : typarams) |
469 | chk.checkNonCyclic(tvar.pos(), (TypeVar)tvar.type); |
470 | attribStats(typarams, env); |
471 | } |
472 | |
473 | void attribBounds(List<JCTypeParameter> typarams) { |
474 | for (JCTypeParameter typaram : typarams) { |
475 | Type bound = typaram.type.getUpperBound(); |
476 | if (bound != null && bound.tsym instanceof ClassSymbol) { |
477 | ClassSymbol c = (ClassSymbol)bound.tsym; |
478 | if ((c.flags_field & COMPOUND) != 0) { |
479 | assert (c.flags_field & UNATTRIBUTED) != 0 : c; |
480 | attribClass(typaram.pos(), c); |
481 | } |
482 | } |
483 | } |
484 | } |
485 | |
486 | /** |
487 | * Attribute the type references in a list of annotations. |
488 | */ |
489 | void attribAnnotationTypes(List<JCAnnotation> annotations, |
490 | Env<AttrContext> env) { |
491 | for (List<JCAnnotation> al = annotations; al.nonEmpty(); al = al.tail) { |
492 | JCAnnotation a = al.head; |
493 | attribType(a.annotationType, env); |
494 | } |
495 | } |
496 | |
497 | /** Attribute type reference in an `extends' or `implements' clause. |
498 | * |
499 | * @param tree The tree making up the type reference. |
500 | * @param env The environment current at the reference. |
501 | * @param classExpected true if only a class is expected here. |
502 | * @param interfaceExpected true if only an interface is expected here. |
503 | */ |
504 | Type attribBase(JCTree tree, |
505 | Env<AttrContext> env, |
506 | boolean classExpected, |
507 | boolean interfaceExpected, |
508 | boolean checkExtensible) { |
509 | Type t = attribType(tree, env); |
510 | return checkBase(t, tree, env, classExpected, interfaceExpected, checkExtensible); |
511 | } |
512 | Type checkBase(Type t, |
513 | JCTree tree, |
514 | Env<AttrContext> env, |
515 | boolean classExpected, |
516 | boolean interfaceExpected, |
517 | boolean checkExtensible) { |
518 | if (t.tag == TYPEVAR && !classExpected && !interfaceExpected) { |
519 | // check that type variable is already visible |
520 | if (t.getUpperBound() == null) { |
521 | log.error(tree.pos(), "illegal.forward.ref"); |
522 | return syms.errType; |
523 | } |
524 | } else { |
525 | t = chk.checkClassType(tree.pos(), t, checkExtensible|!allowGenerics); |
526 | } |
527 | if (interfaceExpected && (t.tsym.flags() & INTERFACE) == 0) { |
528 | log.error(tree.pos(), "intf.expected.here"); |
529 | // return errType is necessary since otherwise there might |
530 | // be undetected cycles which cause attribution to loop |
531 | return syms.errType; |
532 | } else if (checkExtensible && |
533 | classExpected && |
534 | (t.tsym.flags() & INTERFACE) != 0) { |
535 | log.error(tree.pos(), "no.intf.expected.here"); |
536 | return syms.errType; |
537 | } |
538 | if (checkExtensible && |
539 | ((t.tsym.flags() & FINAL) != 0)) { |
540 | log.error(tree.pos(), |
541 | "cant.inherit.from.final", t.tsym); |
542 | } |
543 | chk.checkNonCyclic(tree.pos(), t); |
544 | return t; |
545 | } |
546 | |
547 | public void visitClassDef(JCClassDecl tree) { |
548 | // Local classes have not been entered yet, so we need to do it now: |
549 | if ((env.info.scope.owner.kind & (VAR | MTH)) != 0) |
550 | enter.classEnter(tree, env); |
551 | |
552 | ClassSymbol c = tree.sym; |
553 | if (c == null) { |
554 | // exit in case something drastic went wrong during enter. |
555 | result = null; |
556 | } else { |
557 | // make sure class has been completed: |
558 | c.complete(); |
559 | |
560 | // If this class appears as an anonymous class |
561 | // in a superclass constructor call where |
562 | // no explicit outer instance is given, |
563 | // disable implicit outer instance from being passed. |
564 | // (This would be an illegal access to "this before super"). |
565 | if (env.info.isSelfCall && |
566 | env.tree.getTag() == JCTree.NEWCLASS && |
567 | ((JCNewClass) env.tree).encl == null) |
568 | { |
569 | c.flags_field |= NOOUTERTHIS; |
570 | } |
571 | attribClass(tree.pos(), c); |
572 | result = tree.type = c.type; |
573 | } |
574 | } |
575 | |
576 | public void visitMethodDef(JCMethodDecl tree) { |
577 | MethodSymbol m = tree.sym; |
578 | |
579 | Lint lint = env.info.lint.augment(m.attributes_field, m.flags()); |
580 | Lint prevLint = chk.setLint(lint); |
581 | try { |
582 | chk.checkDeprecatedAnnotation(tree.pos(), m); |
583 | |
584 | attribBounds(tree.typarams); |
585 | |
586 | // If we override any other methods, check that we do so properly. |
587 | // JLS ??? |
588 | chk.checkOverride(tree, m); |
589 | |
590 | // Create a new environment with local scope |
591 | // for attributing the method. |
592 | Env<AttrContext> localEnv = memberEnter.methodEnv(tree, env); |
593 | |
594 | localEnv.info.lint = lint; |
595 | |
596 | // Enter all type parameters into the local method scope. |
597 | for (List<JCTypeParameter> l = tree.typarams; l.nonEmpty(); l = l.tail) |
598 | localEnv.info.scope.enterIfAbsent(l.head.type.tsym); |
599 | |
600 | ClassSymbol owner = env.enclClass.sym; |
601 | if ((owner.flags() & ANNOTATION) != 0 && |
602 | tree.params.nonEmpty()) |
603 | log.error(tree.params.head.pos(), |
604 | "intf.annotation.members.cant.have.params"); |
605 | |
606 | // Attribute all value parameters. |
607 | for (List<JCVariableDecl> l = tree.params; l.nonEmpty(); l = l.tail) { |
608 | attribStat(l.head, localEnv); |
609 | } |
610 | |
611 | // Check that type parameters are well-formed. |
612 | chk.validateTypeParams(tree.typarams); |
613 | if ((owner.flags() & ANNOTATION) != 0 && |
614 | tree.typarams.nonEmpty()) |
615 | log.error(tree.typarams.head.pos(), |
616 | "intf.annotation.members.cant.have.type.params"); |
617 | |
618 | // Check that result type is well-formed. |
619 | chk.validate(tree.restype); |
620 | if ((owner.flags() & ANNOTATION) != 0) |
621 | chk.validateAnnotationType(tree.restype); |
622 | |
623 | if ((owner.flags() & ANNOTATION) != 0) |
624 | chk.validateAnnotationMethod(tree.pos(), m); |
625 | |
626 | // Check that all exceptions mentioned in the throws clause extend |
627 | // java.lang.Throwable. |
628 | if ((owner.flags() & ANNOTATION) != 0 && tree.thrown.nonEmpty()) |
629 | log.error(tree.thrown.head.pos(), |
630 | "throws.not.allowed.in.intf.annotation"); |
631 | for (List<JCExpression> l = tree.thrown; l.nonEmpty(); l = l.tail) |
632 | chk.checkType(l.head.pos(), l.head.type, syms.throwableType); |
633 | |
634 | if (tree.body == null) { |
635 | // Empty bodies are only allowed for |
636 | // abstract, native, or interface methods, or for methods |
637 | // in a retrofit signature class. |
638 | if ((owner.flags() & INTERFACE) == 0 && |
639 | (tree.mods.flags & (ABSTRACT | NATIVE)) == 0 && |
640 | !relax) |
641 | log.error(tree.pos(), "missing.meth.body.or.decl.abstract"); |
642 | if (tree.defaultValue != null) { |
643 | if ((owner.flags() & ANNOTATION) == 0) |
644 | log.error(tree.pos(), |
645 | "default.allowed.in.intf.annotation.member"); |
646 | } |
647 | } else if ((owner.flags() & INTERFACE) != 0) { |
648 | log.error(tree.body.pos(), "intf.meth.cant.have.body"); |
649 | } else if ((tree.mods.flags & ABSTRACT) != 0) { |
650 | log.error(tree.pos(), "abstract.meth.cant.have.body"); |
651 | } else if ((tree.mods.flags & NATIVE) != 0) { |
652 | log.error(tree.pos(), "native.meth.cant.have.body"); |
653 | } else { |
654 | // Add an implicit super() call unless an explicit call to |
655 | // super(...) or this(...) is given |
656 | // or we are compiling class java.lang.Object. |
657 | if (tree.name == names.init && owner.type != syms.objectType) { |
658 | JCBlock body = tree.body; |
659 | if (body.stats.isEmpty() || |
660 | !TreeInfo.isSelfCall(body.stats.head)) { |
661 | body.stats = body.stats. |
662 | prepend(memberEnter.SuperCall(make.at(body.pos), |
663 | List.<Type>nil(), |
664 | List.<JCVariableDecl>nil(), |
665 | false)); |
666 | } else if ((env.enclClass.sym.flags() & ENUM) != 0 && |
667 | (tree.mods.flags & GENERATEDCONSTR) == 0 && |
668 | TreeInfo.isSuperCall(body.stats.head)) { |
669 | // enum constructors are not allowed to call super |
670 | // directly, so make sure there aren't any super calls |
671 | // in enum constructors, except in the compiler |
672 | // generated one. |
673 | log.error(tree.body.stats.head.pos(), |
674 | "call.to.super.not.allowed.in.enum.ctor", |
675 | env.enclClass.sym); |
676 | } |
677 | } |
678 | |
679 | // Attribute method body. |
680 | attribStat(tree.body, localEnv); |
681 | } |
682 | localEnv.info.scope.leave(); |
683 | result = tree.type = m.type; |
684 | chk.validateAnnotations(tree.mods.annotations, m); |
685 | |
686 | } |
687 | finally { |
688 | chk.setLint(prevLint); |
689 | } |
690 | } |
691 | |
692 | public void visitVarDef(JCVariableDecl tree) { |
693 | // Local variables have not been entered yet, so we need to do it now: |
694 | if (env.info.scope.owner.kind == MTH) { |
695 | if (tree.sym != null) { |
696 | // parameters have already been entered |
697 | env.info.scope.enter(tree.sym); |
698 | } else { |
699 | memberEnter.memberEnter(tree, env); |
700 | annotate.flush(); |
701 | } |
702 | } |
703 | |
704 | // Check that the variable's declared type is well-formed. |
705 | chk.validate(tree.vartype); |
706 | |
707 | VarSymbol v = tree.sym; |
708 | Lint lint = env.info.lint.augment(v.attributes_field, v.flags()); |
709 | Lint prevLint = chk.setLint(lint); |
710 | |
711 | try { |
712 | chk.checkDeprecatedAnnotation(tree.pos(), v); |
713 | |
714 | if (tree.init != null) { |
715 | if ((v.flags_field & FINAL) != 0 && tree.init.getTag() != JCTree.NEWCLASS) { |
716 | // In this case, `v' is final. Ensure that it's initializer is |
717 | // evaluated. |
718 | v.getConstValue(); // ensure initializer is evaluated |
719 | } else { |
720 | // Attribute initializer in a new environment |
721 | // with the declared variable as owner. |
722 | // Check that initializer conforms to variable's declared type. |
723 | Env<AttrContext> initEnv = memberEnter.initEnv(tree, env); |
724 | initEnv.info.lint = lint; |
725 | // In order to catch self-references, we set the variable's |
726 | // declaration position to maximal possible value, effectively |
727 | // marking the variable as undefined. |
728 | v.pos = Position.MAXPOS; |
729 | attribExpr(tree.init, initEnv, v.type); |
730 | v.pos = tree.pos; |
731 | } |
732 | } |
733 | result = tree.type = v.type; |
734 | chk.validateAnnotations(tree.mods.annotations, v); |
735 | } |
736 | finally { |
737 | chk.setLint(prevLint); |
738 | } |
739 | } |
740 | |
741 | public void visitSkip(JCSkip tree) { |
742 | result = null; |
743 | } |
744 | |
745 | public void visitBlock(JCBlock tree) { |
746 | if (env.info.scope.owner.kind == TYP) { |
747 | // Block is a static or instance initializer; |
748 | // let the owner of the environment be a freshly |
749 | // created BLOCK-method. |
750 | Env<AttrContext> localEnv = |
751 | env.dup(tree, env.info.dup(env.info.scope.dupUnshared())); |
752 | localEnv.info.scope.owner = |
753 | new MethodSymbol(tree.flags | BLOCK, names.empty, null, |
754 | env.info.scope.owner); |
755 | if ((tree.flags & STATIC) != 0) localEnv.info.staticLevel++; |
756 | attribStats(tree.stats, localEnv); |
757 | } else { |
758 | // Create a new local environment with a local scope. |
759 | Env<AttrContext> localEnv = |
760 | env.dup(tree, env.info.dup(env.info.scope.dup())); |
761 | attribStats(tree.stats, localEnv); |
762 | localEnv.info.scope.leave(); |
763 | } |
764 | result = null; |
765 | } |
766 | |
767 | public void visitDoLoop(JCDoWhileLoop tree) { |
768 | attribStat(tree.body, env.dup(tree)); |
769 | attribExpr(tree.cond, env, syms.booleanType); |
770 | result = null; |
771 | } |
772 | |
773 | public void visitWhileLoop(JCWhileLoop tree) { |
774 | attribExpr(tree.cond, env, syms.booleanType); |
775 | attribStat(tree.body, env.dup(tree)); |
776 | result = null; |
777 | } |
778 | |
779 | public void visitForLoop(JCForLoop tree) { |
780 | Env<AttrContext> loopEnv = |
781 | env.dup(env.tree, env.info.dup(env.info.scope.dup())); |
782 | attribStats(tree.init, loopEnv); |
783 | if (tree.cond != null) attribExpr(tree.cond, loopEnv, syms.booleanType); |
784 | loopEnv.tree = tree; // before, we were not in loop! |
785 | attribStats(tree.step, loopEnv); |
786 | attribStat(tree.body, loopEnv); |
787 | loopEnv.info.scope.leave(); |
788 | result = null; |
789 | } |
790 | |
791 | public void visitForeachLoop(JCEnhancedForLoop tree) { |
792 | Env<AttrContext> loopEnv = |
793 | env.dup(env.tree, env.info.dup(env.info.scope.dup())); |
794 | attribStat(tree.var, loopEnv); |
795 | Type exprType = types.upperBound(attribExpr(tree.expr, loopEnv)); |
796 | chk.checkNonVoid(tree.pos(), exprType); |
797 | Type elemtype = types.elemtype(exprType); // perhaps expr is an array? |
798 | if (elemtype == null) { |
799 | // or perhaps expr implements Iterable<T>? |
800 | Type base = types.asSuper(exprType, syms.iterableType.tsym); |
801 | if (base == null) { |
802 | log.error(tree.expr.pos(), "foreach.not.applicable.to.type"); |
803 | elemtype = syms.errType; |
804 | } else { |
805 | List<Type> iterableParams = base.allparams(); |
806 | elemtype = iterableParams.isEmpty() |
807 | ? syms.objectType |
808 | : types.upperBound(iterableParams.head); |
809 | } |
810 | } |
811 | chk.checkType(tree.expr.pos(), elemtype, tree.var.sym.type); |
812 | loopEnv.tree = tree; // before, we were not in loop! |
813 | attribStat(tree.body, loopEnv); |
814 | loopEnv.info.scope.leave(); |
815 | result = null; |
816 | } |
817 | |
818 | public void visitLabelled(JCLabeledStatement tree) { |
819 | // Check that label is not used in an enclosing statement |
820 | Env<AttrContext> env1 = env; |
821 | while (env1 != null && env1.tree.getTag() != JCTree.CLASSDEF) { |
822 | if (env1.tree.getTag() == JCTree.LABELLED && |
823 | ((JCLabeledStatement) env1.tree).label == tree.label) { |
824 | log.error(tree.pos(), "label.already.in.use", |
825 | tree.label); |
826 | break; |
827 | } |
828 | env1 = env1.next; |
829 | } |
830 | |
831 | attribStat(tree.body, env.dup(tree)); |
832 | result = null; |
833 | } |
834 | |
835 | public void visitSwitch(JCSwitch tree) { |
836 | Type seltype = attribExpr(tree.selector, env); |
837 | |
838 | Env<AttrContext> switchEnv = |
839 | env.dup(tree, env.info.dup(env.info.scope.dup())); |
840 | |
841 | boolean enumSwitch = |
842 | allowEnums && |
843 | (seltype.tsym.flags() & Flags.ENUM) != 0; |
844 | if (!enumSwitch) |
845 | seltype = chk.checkType(tree.selector.pos(), seltype, syms.intType); |
846 | |
847 | // Attribute all cases and |
848 | // check that there are no duplicate case labels or default clauses. |
849 | Set<Object> labels = new HashSet<Object>(); // The set of case labels. |
850 | boolean hasDefault = false; // Is there a default label? |
851 | for (List<JCCase> l = tree.cases; l.nonEmpty(); l = l.tail) { |
852 | JCCase c = l.head; |
853 | Env<AttrContext> caseEnv = |
854 | switchEnv.dup(c, env.info.dup(switchEnv.info.scope.dup())); |
855 | if (c.pat != null) { |
856 | if (enumSwitch) { |
857 | Symbol sym = enumConstant(c.pat, seltype); |
858 | if (sym == null) { |
859 | log.error(c.pat.pos(), "enum.const.req"); |
860 | } else if (!labels.add(sym)) { |
861 | log.error(c.pos(), "duplicate.case.label"); |
862 | } |
863 | } else { |
864 | Type pattype = attribExpr(c.pat, switchEnv, seltype); |
865 | if (pattype.tag != ERROR) { |
866 | if (pattype.constValue() == null) { |
867 | log.error(c.pat.pos(), "const.expr.req"); |
868 | } else if (labels.contains(pattype.constValue())) { |
869 | log.error(c.pos(), "duplicate.case.label"); |
870 | } else { |
871 | labels.add(pattype.constValue()); |
872 | } |
873 | } |
874 | } |
875 | } else if (hasDefault) { |
876 | log.error(c.pos(), "duplicate.default.label"); |
877 | } else { |
878 | hasDefault = true; |
879 | } |
880 | attribStats(c.stats, caseEnv); |
881 | caseEnv.info.scope.leave(); |
882 | addVars(c.stats, switchEnv.info.scope); |
883 | } |
884 | |
885 | switchEnv.info.scope.leave(); |
886 | result = null; |
887 | } |
888 | // where |
889 | /** Add any variables defined in stats to the switch scope. */ |
890 | private static void addVars(List<JCStatement> stats, Scope switchScope) { |
891 | for (;stats.nonEmpty(); stats = stats.tail) { |
892 | JCTree stat = stats.head; |
893 | if (stat.getTag() == JCTree.VARDEF) |
894 | switchScope.enter(((JCVariableDecl) stat).sym); |
895 | } |
896 | } |
897 | // where |
898 | /** Return the selected enumeration constant symbol, or null. */ |
899 | private Symbol enumConstant(JCTree tree, Type enumType) { |
900 | if (tree.getTag() != JCTree.IDENT) { |
901 | log.error(tree.pos(), "enum.label.must.be.unqualified.enum"); |
902 | return syms.errSymbol; |
903 | } |
904 | JCIdent ident = (JCIdent)tree; |
905 | Name name = ident.name; |
906 | for (Scope.Entry e = enumType.tsym.members().lookup(name); |
907 | e.scope != null; e = e.next()) { |
908 | if (e.sym.kind == VAR) { |
909 | Symbol s = ident.sym = e.sym; |
910 | ((VarSymbol)s).getConstValue(); // ensure initializer is evaluated |
911 | ident.type = s.type; |
912 | return ((s.flags_field & Flags.ENUM) == 0) |
913 | ? null : s; |
914 | } |
915 | } |
916 | return null; |
917 | } |
918 | |
919 | public void visitSynchronized(JCSynchronized tree) { |
920 | chk.checkRefType(tree.pos(), attribExpr(tree.lock, env)); |
921 | attribStat(tree.body, env); |
922 | result = null; |
923 | } |
924 | |
925 | public void visitTry(JCTry tree) { |
926 | // Attribute body |
927 | attribStat(tree.body, env.dup(tree, env.info.dup())); |
928 | |
929 | // Attribute catch clauses |
930 | for (List<JCCatch> l = tree.catchers; l.nonEmpty(); l = l.tail) { |
931 | JCCatch c = l.head; |
932 | Env<AttrContext> catchEnv = |
933 | env.dup(c, env.info.dup(env.info.scope.dup())); |
934 | Type ctype = attribStat(c.param, catchEnv); |
935 | if (c.param.type.tsym.kind == Kinds.VAR) { |
936 | c.param.sym.setData(ElementKind.EXCEPTION_PARAMETER); |
937 | } |
938 | chk.checkType(c.param.vartype.pos(), |
939 | chk.checkClassType(c.param.vartype.pos(), ctype), |
940 | syms.throwableType); |
941 | attribStat(c.body, catchEnv); |
942 | catchEnv.info.scope.leave(); |
943 | } |
944 | |
945 | // Attribute finalizer |
946 | if (tree.finalizer != null) attribStat(tree.finalizer, env); |
947 | result = null; |
948 | } |
949 | |
950 | public void visitConditional(JCConditional tree) { |
951 | attribExpr(tree.cond, env, syms.booleanType); |
952 | attribExpr(tree.truepart, env); |
953 | attribExpr(tree.falsepart, env); |
954 | result = check(tree, |
955 | capture(condType(tree.pos(), tree.cond.type, |
956 | tree.truepart.type, tree.falsepart.type)), |
957 | VAL, pkind, pt); |
958 | } |
959 | //where |
960 | /** Compute the type of a conditional expression, after |
961 | * checking that it exists. See Spec 15.25. |
962 | * |
963 | * @param pos The source position to be used for |
964 | * error diagnostics. |
965 | * @param condtype The type of the expression's condition. |
966 | * @param thentype The type of the expression's then-part. |
967 | * @param elsetype The type of the expression's else-part. |
968 | */ |
969 | private Type condType(DiagnosticPosition pos, |
970 | Type condtype, |
971 | Type thentype, |
972 | Type elsetype) { |
973 | Type ctype = condType1(pos, condtype, thentype, elsetype); |
974 | |
975 | // If condition and both arms are numeric constants, |
976 | // evaluate at compile-time. |
977 | return ((condtype.constValue() != null) && |
978 | (thentype.constValue() != null) && |
979 | (elsetype.constValue() != null)) |
980 | ? cfolder.coerce(condtype.isTrue()?thentype:elsetype, ctype) |
981 | : ctype; |
982 | } |
983 | /** Compute the type of a conditional expression, after |
984 | * checking that it exists. Does not take into |
985 | * account the special case where condition and both arms |
986 | * are constants. |
987 | * |
988 | * @param pos The source position to be used for error |
989 | * diagnostics. |
990 | * @param condtype The type of the expression's condition. |
991 | * @param thentype The type of the expression's then-part. |
992 | * @param elsetype The type of the expression's else-part. |
993 | */ |
994 | private Type condType1(DiagnosticPosition pos, Type condtype, |
995 | Type thentype, Type elsetype) { |
996 | // If same type, that is the result |
997 | if (types.isSameType(thentype, elsetype)) |
998 | return thentype.baseType(); |
999 | |
1000 | Type thenUnboxed = (!allowBoxing || thentype.isPrimitive()) |
1001 | ? thentype : types.unboxedType(thentype); |
1002 | Type elseUnboxed = (!allowBoxing || elsetype.isPrimitive()) |
1003 | ? elsetype : types.unboxedType(elsetype); |
1004 | |
1005 | // Otherwise, if both arms can be converted to a numeric |
1006 | // type, return the least numeric type that fits both arms |
1007 | // (i.e. return larger of the two, or return int if one |
1008 | // arm is short, the other is char). |
1009 | if (thenUnboxed.isPrimitive() && elseUnboxed.isPrimitive()) { |
1010 | // If one arm has an integer subrange type (i.e., byte, |
1011 | // short, or char), and the other is an integer constant |
1012 | // that fits into the subrange, return the subrange type. |
1013 | if (thenUnboxed.tag < INT && elseUnboxed.tag == INT && |
1014 | types.isAssignable(elseUnboxed, thenUnboxed)) |
1015 | return thenUnboxed.baseType(); |
1016 | if (elseUnboxed.tag < INT && thenUnboxed.tag == INT && |
1017 | types.isAssignable(thenUnboxed, elseUnboxed)) |
1018 | return elseUnboxed.baseType(); |
1019 | |
1020 | for (int i = BYTE; i < VOID; i++) { |
1021 | Type candidate = syms.typeOfTag[i]; |
1022 | if (types.isSubtype(thenUnboxed, candidate) && |
1023 | types.isSubtype(elseUnboxed, candidate)) |
1024 | return candidate; |
1025 | } |
1026 | } |
1027 | |
1028 | // Those were all the cases that could result in a primitive |
1029 | if (allowBoxing) { |
1030 | if (thentype.isPrimitive()) |
1031 | thentype = types.boxedClass(thentype).type; |
1032 | if (elsetype.isPrimitive()) |
1033 | elsetype = types.boxedClass(elsetype).type; |
1034 | } |
1035 | |
1036 | if (types.isSubtype(thentype, elsetype)) |
1037 | return elsetype.baseType(); |
1038 | if (types.isSubtype(elsetype, thentype)) |
1039 | return thentype.baseType(); |
1040 | |
1041 | if (!allowBoxing || thentype.tag == VOID || elsetype.tag == VOID) { |
1042 | log.error(pos, "neither.conditional.subtype", |
1043 | thentype, elsetype); |
1044 | return thentype.baseType(); |
1045 | } |
1046 | |
1047 | // both are known to be reference types. The result is |
1048 | // lub(thentype,elsetype). This cannot fail, as it will |
1049 | // always be possible to infer "Object" if nothing better. |
1050 | return types.lub(thentype.baseType(), elsetype.baseType()); |
1051 | } |
1052 | |
1053 | public void visitIf(JCIf tree) { |
1054 | attribExpr(tree.cond, env, syms.booleanType); |
1055 | attribStat(tree.thenpart, env); |
1056 | if (tree.elsepart != null) |
1057 | attribStat(tree.elsepart, env); |
1058 | chk.checkEmptyIf(tree); |
1059 | result = null; |
1060 | } |
1061 | |
1062 | public void visitExec(JCExpressionStatement tree) { |
1063 | attribExpr(tree.expr, env); |
1064 | result = null; |
1065 | } |
1066 | |
1067 | public void visitBreak(JCBreak tree) { |
1068 | tree.target = findJumpTarget(tree.pos(), tree.getTag(), tree.label, env); |
1069 | result = null; |
1070 | } |
1071 | |
1072 | public void visitContinue(JCContinue tree) { |
1073 | tree.target = findJumpTarget(tree.pos(), tree.getTag(), tree.label, env); |
1074 | result = null; |
1075 | } |
1076 | //where |
1077 | /** Return the target of a break or continue statement, if it exists, |
1078 | * report an error if not. |
1079 | * Note: The target of a labelled break or continue is the |
1080 | * (non-labelled) statement tree referred to by the label, |
1081 | * not the tree representing the labelled statement itself. |
1082 | * |
1083 | * @param pos The position to be used for error diagnostics |
1084 | * @param tag The tag of the jump statement. This is either |
1085 | * Tree.BREAK or Tree.CONTINUE. |
1086 | * @param label The label of the jump statement, or null if no |
1087 | * label is given. |
1088 | * @param env The environment current at the jump statement. |
1089 | */ |
1090 | private JCTree findJumpTarget(DiagnosticPosition pos, |
1091 | int tag, |
1092 | Name label, |
1093 | Env<AttrContext> env) { |
1094 | // Search environments outwards from the point of jump. |
1095 | Env<AttrContext> env1 = env; |
1096 | LOOP: |
1097 | while (env1 != null) { |
1098 | switch (env1.tree.getTag()) { |
1099 | case JCTree.LABELLED: |
1100 | JCLabeledStatement labelled = (JCLabeledStatement)env1.tree; |
1101 | if (label == labelled.label) { |
1102 | // If jump is a continue, check that target is a loop. |
1103 | if (tag == JCTree.CONTINUE) { |
1104 | if (labelled.body.getTag() != JCTree.DOLOOP && |
1105 | labelled.body.getTag() != JCTree.WHILELOOP && |
1106 | labelled.body.getTag() != JCTree.FORLOOP && |
1107 | labelled.body.getTag() != JCTree.FOREACHLOOP) |
1108 | log.error(pos, "not.loop.label", label); |
1109 | // Found labelled statement target, now go inwards |
1110 | // to next non-labelled tree. |
1111 | return TreeInfo.referencedStatement(labelled); |
1112 | } else { |
1113 | return labelled; |
1114 | } |
1115 | } |
1116 | break; |
1117 | case JCTree.DOLOOP: |
1118 | case JCTree.WHILELOOP: |
1119 | case JCTree.FORLOOP: |
1120 | case JCTree.FOREACHLOOP: |
1121 | if (label == null) return env1.tree; |
1122 | break; |
1123 | case JCTree.SWITCH: |
1124 | if (label == null && tag == JCTree.BREAK) return env1.tree; |
1125 | break; |
1126 | case JCTree.METHODDEF: |
1127 | case JCTree.CLASSDEF: |
1128 | break LOOP; |
1129 | default: |
1130 | } |
1131 | env1 = env1.next; |
1132 | } |
1133 | if (label != null) |
1134 | log.error(pos, "undef.label", label); |
1135 | else if (tag == JCTree.CONTINUE) |
1136 | log.error(pos, "cont.outside.loop"); |
1137 | else |
1138 | log.error(pos, "break.outside.switch.loop"); |
1139 | return null; |
1140 | } |
1141 | |
1142 | public void visitReturn(JCReturn tree) { |
1143 | // Check that there is an enclosing method which is |
1144 | // nested within than the enclosing class. |
1145 | if (env.enclMethod == null || |
1146 | env.enclMethod.sym.owner != env.enclClass.sym) { |
1147 | log.error(tree.pos(), "ret.outside.meth"); |
1148 | |
1149 | } else { |
1150 | // Attribute return expression, if it exists, and check that |
1151 | // it conforms to result type of enclosing method. |
1152 | Symbol m = env.enclMethod.sym; |
1153 | if (m.type.getReturnType().tag == VOID) { |
1154 | if (tree.expr != null) |
1155 | log.error(tree.expr.pos(), |
1156 | "cant.ret.val.from.meth.decl.void"); |
1157 | } else if (tree.expr == null) { |
1158 | log.error(tree.pos(), "missing.ret.val"); |
1159 | } else { |
1160 | attribExpr(tree.expr, env, m.type.getReturnType()); |
1161 | } |
1162 | } |
1163 | result = null; |
1164 | } |
1165 | |
1166 | public void visitThrow(JCThrow tree) { |
1167 | attribExpr(tree.expr, env, syms.throwableType); |
1168 | result = null; |
1169 | } |
1170 | |
1171 | public void visitAssert(JCAssert tree) { |
1172 | attribExpr(tree.cond, env, syms.booleanType); |
1173 | if (tree.detail != null) { |
1174 | chk.checkNonVoid(tree.detail.pos(), attribExpr(tree.detail, env)); |
1175 | } |
1176 | result = null; |
1177 | } |
1178 | |
1179 | /** Visitor method for method invocations. |
1180 | * NOTE: The method part of an application will have in its type field |
1181 | * the return type of the method, not the method's type itself! |
1182 | */ |
1183 | public void visitApply(JCMethodInvocation tree) { |
1184 | // The local environment of a method application is |
1185 | // a new environment nested in the current one. |
1186 | Env<AttrContext> localEnv = env.dup(tree, env.info.dup()); |
1187 | |
1188 | // The types of the actual method arguments. |
1189 | List<Type> argtypes; |
1190 | |
1191 | // The types of the actual method type arguments. |
1192 | List<Type> typeargtypes = null; |
1193 | |
1194 | Name methName = TreeInfo.name(tree.meth); |
1195 | |
1196 | boolean isConstructorCall = |
1197 | methName == names._this || methName == names._super; |
1198 | |
1199 | if (isConstructorCall) { |
1200 | // We are seeing a ...this(...) or ...super(...) call. |
1201 | // Check that this is the first statement in a constructor. |
1202 | if (checkFirstConstructorStat(tree, env)) { |
1203 | |
1204 | // Record the fact |
1205 | // that this is a constructor call (using isSelfCall). |
1206 | localEnv.info.isSelfCall = true; |
1207 | |
1208 | // Attribute arguments, yielding list of argument types. |
1209 | argtypes = attribArgs(tree.args, localEnv); |
1210 | typeargtypes = attribTypes(tree.typeargs, localEnv); |
1211 | |
1212 | // Variable `site' points to the class in which the called |
1213 | // constructor is defined. |
1214 | Type site = env.enclClass.sym.type; |
1215 | if (methName == names._super) { |
1216 | if (site == syms.objectType) { |
1217 | log.error(tree.meth.pos(), "no.superclass", site); |
1218 | site = syms.errType; |
1219 | } else { |
1220 | site = types.supertype(site); |
1221 | } |
1222 | } |
1223 | |
1224 | if (site.tag == CLASS) { |
1225 | if (site.getEnclosingType().tag == CLASS) { |
1226 | // we are calling a nested class |
1227 | |
1228 | if (tree.meth.getTag() == JCTree.SELECT) { |
1229 | JCTree qualifier = ((JCFieldAccess) tree.meth).selected; |
1230 | |
1231 | // We are seeing a prefixed call, of the form |
1232 | // <expr>.super(...). |
1233 | // Check that the prefix expression conforms |
1234 | // to the outer instance type of the class. |
1235 | chk.checkRefType(qualifier.pos(), |
1236 | attribExpr(qualifier, localEnv, |
1237 | site.getEnclosingType())); |
1238 | } else if (methName == names._super) { |
1239 | // qualifier omitted; check for existence |
1240 | // of an appropriate implicit qualifier. |
1241 | rs.resolveImplicitThis(tree.meth.pos(), |
1242 | localEnv, site); |
1243 | } |
1244 | } else if (tree.meth.getTag() == JCTree.SELECT) { |
1245 | log.error(tree.meth.pos(), "illegal.qual.not.icls", |
1246 | site.tsym); |
1247 | } |
1248 | |
1249 | // if we're calling a java.lang.Enum constructor, |
1250 | // prefix the implicit String and int parameters |
1251 | if (site.tsym == syms.enumSym && allowEnums) |
1252 | argtypes = argtypes.prepend(syms.intType).prepend(syms.stringType); |
1253 | |
1254 | // Resolve the called constructor under the assumption |
1255 | // that we are referring to a superclass instance of the |
1256 | // current instance (JLS ???). |
1257 | boolean selectSuperPrev = localEnv.info.selectSuper; |
1258 | localEnv.info.selectSuper = true; |
1259 | localEnv.info.varArgs = false; |
1260 | Symbol sym = rs.resolveConstructor( |
1261 | tree.meth.pos(), localEnv, site, argtypes, typeargtypes); |
1262 | localEnv.info.selectSuper = selectSuperPrev; |
1263 | |
1264 | // Set method symbol to resolved constructor... |
1265 | TreeInfo.setSymbol(tree.meth, sym); |
1266 | |
1267 | // ...and check that it is legal in the current context. |
1268 | // (this will also set the tree's type) |
1269 | Type mpt = newMethTemplate(argtypes, typeargtypes); |
1270 | checkId(tree.meth, site, sym, localEnv, MTH, |
1271 | mpt, tree.varargsElement != null); |
1272 | } |
1273 | // Otherwise, `site' is an error type and we do nothing |
1274 | } |
1275 | result = tree.type = syms.voidType; |
1276 | } else { |
1277 | // Otherwise, we are seeing a regular method call. |
1278 | // Attribute the arguments, yielding list of argument types, ... |
1279 | argtypes = attribArgs(tree.args, localEnv); |
1280 | typeargtypes = attribTypes(tree.typeargs, localEnv); |
1281 | |
1282 | // ... and attribute the method using as a prototype a methodtype |
1283 | // whose formal argument types is exactly the list of actual |
1284 | // arguments (this will also set the method symbol). |
1285 | Type mpt = newMethTemplate(argtypes, typeargtypes); |
1286 | localEnv.info.varArgs = false; |
1287 | Type mtype = attribExpr(tree.meth, localEnv, mpt); |
1288 | if (localEnv.info.varArgs) |
1289 | assert mtype.isErroneous() || tree.varargsElement != null; |
1290 | |
1291 | // Compute the result type. |
1292 | Type restype = mtype.getReturnType(); |
1293 | assert restype.tag != WILDCARD : mtype; |
1294 | |
1295 | // as a special case, array.clone() has a result that is |
1296 | // the same as static type of the array being cloned |
1297 | if (tree.meth.getTag() == JCTree.SELECT && |
1298 | allowCovariantReturns && |
1299 | methName == names.clone && |
1300 | types.isArray(((JCFieldAccess) tree.meth).selected.type)) |
1301 | restype = ((JCFieldAccess) tree.meth).selected.type; |
1302 | |
1303 | // as a special case, x.getClass() has type Class<? extends |X|> |
1304 | if (allowGenerics && |
1305 | methName == names.getClass && tree.args.isEmpty()) { |
1306 | Type qualifier = (tree.meth.getTag() == JCTree.SELECT) |
1307 | ? ((JCFieldAccess) tree.meth).selected.type |
1308 | : env.enclClass.sym.type; |
1309 | restype = new |
1310 | ClassType(restype.getEnclosingType(), |
1311 | List.<Type>of(new WildcardType(types.erasure(qualifier), |
1312 | BoundKind.EXTENDS, |
1313 | syms.boundClass)), |
1314 | restype.tsym); |
1315 | } |
1316 | |
1317 | // Check that value of resulting type is admissible in the |
1318 | // current context. Also, capture the return type |
1319 | result = check(tree, capture(restype), VAL, pkind, pt); |
1320 | } |
1321 | chk.validate(tree.typeargs); |
1322 | } |
1323 | //where |
1324 | /** Check that given application node appears as first statement |
1325 | * in a constructor call. |
1326 | * @param tree The application node |
1327 | * @param env The environment current at the application. |
1328 | */ |
1329 | boolean checkFirstConstructorStat(JCMethodInvocation tree, Env<AttrContext> env) { |
1330 | JCMethodDecl enclMethod = env.enclMethod; |
1331 | if (enclMethod != null && enclMethod.name == names.init) { |
1332 | JCBlock body = enclMethod.body; |
1333 | if (body.stats.head.getTag() == JCTree.EXEC && |
1334 | ((JCExpressionStatement) body.stats.head).expr == tree) |
1335 | return true; |
1336 | } |
1337 | log.error(tree.pos(),"call.must.be.first.stmt.in.ctor", |
1338 | TreeInfo.name(tree.meth)); |
1339 | return false; |
1340 | } |
1341 | |
1342 | /** Obtain a method type with given argument types. |
1343 | */ |
1344 | Type newMethTemplate(List<Type> argtypes, List<Type> typeargtypes) { |
1345 | MethodType mt = new MethodType(argtypes, null, null, syms.methodClass); |
1346 | return (typeargtypes == null) ? mt : (Type)new ForAll(typeargtypes, mt); |
1347 | } |
1348 | |
1349 | public void visitNewClass(JCNewClass tree) { |
1350 | Type owntype = syms.errType; |
1351 | |
1352 | // The local environment of a class creation is |
1353 | // a new environment nested in the current one. |
1354 | Env<AttrContext> localEnv = env.dup(tree, env.info.dup()); |
1355 | |
1356 | // The anonymous inner class definition of the new expression, |
1357 | // if one is defined by it. |
1358 | JCClassDecl cdef = tree.def; |
1359 | |
1360 | // If enclosing class is given, attribute it, and |
1361 | // complete class name to be fully qualified |
1362 | JCExpression clazz = tree.clazz; // Class field following new |
1363 | JCExpression clazzid = // Identifier in class field |
1364 | (clazz.getTag() == JCTree.TYPEAPPLY) |
1365 | ? ((JCTypeApply) clazz).clazz |
1366 | : clazz; |
1367 | |
1368 | JCExpression clazzid1 = clazzid; // The same in fully qualified form |
1369 | |
1370 | if (tree.encl != null) { |
1371 | // We are seeing a qualified new, of the form |
1372 | // <expr>.new C <...> (...) ... |
1373 | // In this case, we let clazz stand for the name of the |
1374 | // allocated class C prefixed with the type of the qualifier |
1375 | // expression, so that we can |
1376 | // resolve it with standard techniques later. I.e., if |
1377 | // <expr> has type T, then <expr>.new C <...> (...) |
1378 | // yields a clazz T.C. |
1379 | Type encltype = chk.checkRefType(tree.encl.pos(), |
1380 | attribExpr(tree.encl, env)); |
1381 | clazzid1 = make.at(clazz.pos).Select(make.Type(encltype), |
1382 | ((JCIdent) clazzid).name); |
1383 | if (clazz.getTag() == JCTree.TYPEAPPLY) |
1384 | clazz = make.at(tree.pos). |
1385 | TypeApply(clazzid1, |
1386 | ((JCTypeApply) clazz).arguments); |
1387 | else |
1388 | clazz = clazzid1; |
1389 | // System.out.println(clazz + " generated.");//DEBUG |
1390 | } |
1391 | |
1392 | // Attribute clazz expression and store |
1393 | // symbol + type back into the attributed tree. |
1394 | Type clazztype = chk.checkClassType( |
1395 | tree.clazz.pos(), attribType(clazz, env), true); |
1396 | chk.validate(clazz); |
1397 | if (tree.encl != null) { |
1398 | // We have to work in this case to store |
1399 | // symbol + type back into the attributed tree. |
1400 | tree.clazz.type = clazztype; |
1401 | TreeInfo.setSymbol(clazzid, TreeInfo.symbol(clazzid1)); |
1402 | clazzid.type = ((JCIdent) clazzid).sym.type; |
1403 | if (!clazztype.isErroneous()) { |
1404 | if (cdef != null && clazztype.tsym.isInterface()) { |
1405 | log.error(tree.encl.pos(), "anon.class.impl.intf.no.qual.for.new"); |
1406 | } else if (clazztype.tsym.isStatic()) { |
1407 | log.error(tree.encl.pos(), "qualified.new.of.static.class", clazztype.tsym); |
1408 | } |
1409 | } |
1410 | } else if (!clazztype.tsym.isInterface() && |
1411 | clazztype.getEnclosingType().tag == CLASS) { |
1412 | // Check for the existence of an apropos outer instance |
1413 | rs.resolveImplicitThis(tree.pos(), env, clazztype); |
1414 | } |
1415 | |
1416 | // Attribute constructor arguments. |
1417 | List<Type> argtypes = attribArgs(tree.args, localEnv); |
1418 | List<Type> typeargtypes = attribTypes(tree.typeargs, localEnv); |
1419 | |
1420 | // If we have made no mistakes in the class type... |
1421 | if (clazztype.tag == CLASS) { |
1422 | // Enums may not be instantiated except implicitly |
1423 | if (allowEnums && |
1424 | (clazztype.tsym.flags_field&Flags.ENUM) != 0 && |
1425 | (env.tree.getTag() != JCTree.VARDEF || |
1426 | (((JCVariableDecl) env.tree).mods.flags&Flags.ENUM) == 0 || |
1427 | ((JCVariableDecl) env.tree).init != tree)) |
1428 | log.error(tree.pos(), "enum.cant.be.instantiated"); |
1429 | // Check that class is not abstract |
1430 | if (cdef == null && |
1431 | (clazztype.tsym.flags() & (ABSTRACT | INTERFACE)) != 0) { |
1432 | log.error(tree.pos(), "abstract.cant.be.instantiated", |
1433 | clazztype.tsym); |
1434 | } else if (cdef != null && clazztype.tsym.isInterface()) { |
1435 | // Check that no constructor arguments are given to |
1436 | // anonymous classes implementing an interface |
1437 | if (!argtypes.isEmpty()) |
1438 | log.error(tree.args.head.pos(), "anon.class.impl.intf.no.args"); |
1439 | |
1440 | if (!typeargtypes.isEmpty()) |
1441 | log.error(tree.typeargs.head.pos(), "anon.class.impl.intf.no.typeargs"); |
1442 | |
1443 | // Error recovery: pretend no arguments were supplied. |
1444 | argtypes = List.nil(); |
1445 | typeargtypes = List.nil(); |
1446 | } |
1447 | |
1448 | // Resolve the called constructor under the assumption |
1449 | // that we are referring to a superclass instance of the |
1450 | // current instance (JLS ???). |
1451 | else { |
1452 | localEnv.info.selectSuper = cdef != null; |
1453 | localEnv.info.varArgs = false; |
1454 | tree.constructor = rs.resolveConstructor( |
1455 | tree.pos(), localEnv, clazztype, argtypes, typeargtypes); |
1456 | Type ctorType = checkMethod(clazztype, |
1457 | tree.constructor, |
1458 | localEnv, |
1459 | tree.args, |
1460 | argtypes, |
1461 | typeargtypes, |
1462 | localEnv.info.varArgs); |
1463 | if (localEnv.info.varArgs) |
1464 | assert ctorType.isErroneous() || tree.varargsElement != null; |
1465 | } |
1466 | |
1467 | if (cdef != null) { |
1468 | // We are seeing an anonymous class instance creation. |
1469 | // In this case, the class instance creation |
1470 | // expression |
1471 | // |
1472 | // E.new <typeargs1>C<typargs2>(args) { ... } |
1473 | // |
1474 | // is represented internally as |
1475 | // |
1476 | // E . new <typeargs1>C<typargs2>(args) ( class <empty-name> { ... } ) . |
1477 | // |
1478 | // This expression is then *transformed* as follows: |
1479 | // |
1480 | // (1) add a STATIC flag to the class definition |
1481 | // if the current environment is static |
1482 | // (2) add an extends or implements clause |
1483 | // (3) add a constructor. |
1484 | // |
1485 | // For instance, if C is a class, and ET is the type of E, |
1486 | // the expression |
1487 | // |
1488 | // E.new <typeargs1>C<typargs2>(args) { ... } |
1489 | // |
1490 | // is translated to (where X is a fresh name and typarams is the |
1491 | // parameter list of the super constructor): |
1492 | // |
1493 | // new <typeargs1>X(<*nullchk*>E, args) where |
1494 | // X extends C<typargs2> { |
1495 | // <typarams> X(ET e, args) { |
1496 | // e.<typeargs1>super(args) |
1497 | // } |
1498 | // ... |
1499 | // } |
1500 | if (Resolve.isStatic(env)) cdef.mods.flags |= STATIC; |
1501 | |
1502 | if (clazztype.tsym.isInterface()) { |
1503 | cdef.implementing = List.of(clazz); |
1504 | } else { |
1505 | cdef.extending = clazz; |
1506 | } |
1507 | |
1508 | attribStat(cdef, localEnv); |
1509 | |
1510 | // If an outer instance is given, |
1511 | // prefix it to the constructor arguments |
1512 | // and delete it from the new expression |
1513 | if (tree.encl != null && !clazztype.tsym.isInterface()) { |
1514 | tree.args = tree.args.prepend(makeNullCheck(tree.encl)); |
1515 | argtypes = argtypes.prepend(tree.encl.type); |
1516 | tree.encl = null; |
1517 | } |
1518 | |
1519 | // Reassign clazztype and recompute constructor. |
1520 | clazztype = cdef.sym.type; |
1521 | Symbol sym = rs.resolveConstructor( |
1522 | tree.pos(), localEnv, clazztype, argtypes, |
1523 | typeargtypes, true, tree.varargsElement != null); |
1524 | assert sym.kind < AMBIGUOUS || tree.constructor.type.isErroneous(); |
1525 | tree.constructor = sym; |
1526 | } |
1527 | |
1528 | if (tree.constructor != null && tree.constructor.kind == MTH) |
1529 | owntype = clazztype; |
1530 | } |
1531 | result = check(tree, owntype, VAL, pkind, pt); |
1532 | chk.validate(tree.typeargs); |
1533 | } |
1534 | |
1535 | /** Make an attributed null check tree. |
1536 | */ |
1537 | public JCExpression makeNullCheck(JCExpression arg) { |
1538 | // optimization: X.this is never null; skip null check |
1539 | Name name = TreeInfo.name(arg); |
1540 | if (name == names._this || name == names._super) return arg; |
1541 | |
1542 | int optag = JCTree.NULLCHK; |
1543 | JCUnary tree = make.at(arg.pos).Unary(optag, arg); |
1544 | tree.operator = syms.nullcheck; |
1545 | tree.type = arg.type; |
1546 | return tree; |
1547 | } |
1548 | |
1549 | public void visitNewArray(JCNewArray tree) { |
1550 | Type owntype = syms.errType; |
1551 | Type elemtype; |
1552 | if (tree.elemtype != null) { |
1553 | elemtype = attribType(tree.elemtype, env); |
1554 | chk.validate(tree.elemtype); |
1555 | owntype = elemtype; |
1556 | for (List<JCExpression> l = tree.dims; l.nonEmpty(); l = l.tail) { |
1557 | attribExpr(l.head, env, syms.intType); |
1558 | owntype = new ArrayType(owntype, syms.arrayClass); |
1559 | } |
1560 | } else { |
1561 | // we are seeing an untyped aggregate { ... } |
1562 | // this is allowed only if the prototype is an array |
1563 | if (pt.tag == ARRAY) { |
1564 | elemtype = types.elemtype(pt); |
1565 | } else { |
1566 | if (pt.tag != ERROR) { |
1567 | log.error(tree.pos(), "illegal.initializer.for.type", |
1568 | pt); |
1569 | } |
1570 | elemtype = syms.errType; |
1571 | } |
1572 | } |
1573 | if (tree.elems != null) { |
1574 | attribExprs(tree.elems, env, elemtype); |
1575 | owntype = new ArrayType(elemtype, syms.arrayClass); |
1576 | } |
1577 | if (!types.isReifiable(elemtype)) |
1578 | log.error(tree.pos(), "generic.array.creation"); |
1579 | result = check(tree, owntype, VAL, pkind, pt); |
1580 | } |
1581 | |
1582 | public void visitParens(JCParens tree) { |
1583 | Type owntype = attribTree(tree.expr, env, pkind, pt); |
1584 | result = check(tree, owntype, pkind, pkind, pt); |
1585 | Symbol sym = TreeInfo.symbol(tree); |
1586 | if (sym != null && (sym.kind&(TYP|PCK)) != 0) |
1587 | log.error(tree.pos(), "illegal.start.of.type"); |
1588 | } |
1589 | |
1590 | public void visitAssign(JCAssign tree) { |
1591 | Type owntype = attribTree(tree.lhs, env.dup(tree), VAR, Type.noType); |
1592 | Type capturedType = capture(owntype); |
1593 | attribExpr(tree.rhs, env, owntype); |
1594 | result = check(tree, capturedType, VAL, pkind, pt); |
1595 | } |
1596 | |
1597 | public void visitAssignop(JCAssignOp tree) { |
1598 | // Attribute arguments. |
1599 | Type owntype = attribTree(tree.lhs, env, VAR, Type.noType); |
1600 | Type operand = attribExpr(tree.rhs, env); |
1601 | // Find operator. |
1602 | Symbol operator = tree.operator = rs.resolveBinaryOperator( |
1603 | tree.pos(), tree.getTag() - JCTree.ASGOffset, env, |
1604 | owntype, operand); |
1605 | |
1606 | if (operator.kind == MTH) { |
1607 | chk.checkOperator(tree.pos(), |
1608 | (OperatorSymbol)operator, |
1609 | tree.getTag() - JCTree.ASGOffset, |
1610 | owntype, |
1611 | operand); |
1612 | if (types.isSameType(operator.type.getReturnType(), syms.stringType)) { |
1613 | // String assignment; make sure the lhs is a string |
1614 | chk.checkType(tree.lhs.pos(), |
1615 | owntype, |
1616 | syms.stringType); |
1617 | } else { |
1618 | chk.checkDivZero(tree.rhs.pos(), operator, operand); |
1619 | chk.checkCastable(tree.rhs.pos(), |
1620 | operator.type.getReturnType(), |
1621 | owntype); |
1622 | } |
1623 | } |
1624 | result = check(tree, owntype, VAL, pkind, pt); |
1625 | } |
1626 | |
1627 | public void visitUnary(JCUnary tree) { |
1628 | // Attribute arguments. |
1629 | Type argtype = (JCTree.PREINC <= tree.getTag() && tree.getTag() <= JCTree.POSTDEC) |
1630 | ? attribTree(tree.arg, env, VAR, Type.noType) |
1631 | : chk.checkNonVoid(tree.arg.pos(), attribExpr(tree.arg, env)); |
1632 | |
1633 | // Find operator. |
1634 | Symbol operator = tree.operator = |
1635 | rs.resolveUnaryOperator(tree.pos(), tree.getTag(), env, argtype); |
1636 | |
1637 | Type owntype = syms.errType; |
1638 | if (operator.kind == MTH) { |
1639 | owntype = (JCTree.PREINC <= tree.getTag() && tree.getTag() <= JCTree.POSTDEC) |
1640 | ? tree.arg.type |
1641 | : operator.type.getReturnType(); |
1642 | int opc = ((OperatorSymbol)operator).opcode; |
1643 | |
1644 | // If the argument is constant, fold it. |
1645 | if (argtype.constValue() != null) { |
1646 | Type ctype = cfolder.fold1(opc, argtype); |
1647 | if (ctype != null) { |
1648 | owntype = cfolder.coerce(ctype, owntype); |
1649 | |
1650 | // Remove constant types from arguments to |
1651 | // conserve space. The parser will fold concatenations |
1652 | // of string literals; the code here also |
1653 | // gets rid of intermediate results when some of the |
1654 | // operands are constant identifiers. |
1655 | if (tree.arg.type.tsym == syms.stringType.tsym) { |
1656 | tree.arg.type = syms.stringType; |
1657 | } |
1658 | } |
1659 | } |
1660 | } |
1661 | result = check(tree, owntype, VAL, pkind, pt); |
1662 | } |
1663 | |
1664 | public void visitBinary(JCBinary tree) { |
1665 | // Attribute arguments. |
1666 | Type left = chk.checkNonVoid(tree.lhs.pos(), attribExpr(tree.lhs, env)); |
1667 | Type right = chk.checkNonVoid(tree.lhs.pos(), attribExpr(tree.rhs, env)); |
1668 | |
1669 | // Find operator. |
1670 | Symbol operator = tree.operator = |
1671 | rs.resolveBinaryOperator(tree.pos(), tree.getTag(), env, left, right); |
1672 | |
1673 | Type owntype = syms.errType; |
1674 | if (operator.kind == MTH) { |
1675 | owntype = operator.type.getReturnType(); |
1676 | int opc = chk.checkOperator(tree.lhs.pos(), |
1677 | (OperatorSymbol)operator, |
1678 | tree.getTag(), |
1679 | left, |
1680 | right); |
1681 | |
1682 | // If both arguments are constants, fold them. |
1683 | if (left.constValue() != null && right.constValue() != null) { |
1684 | Type ctype = cfolder.fold2(opc, left, right); |
1685 | if (ctype != null) { |
1686 | owntype = cfolder.coerce(ctype, owntype); |
1687 | |
1688 | // Remove constant types from arguments to |
1689 | // conserve space. The parser will fold concatenations |
1690 | // of string literals; the code here also |
1691 | // gets rid of intermediate results when some of the |
1692 | // operands are constant identifiers. |
1693 | if (tree.lhs.type.tsym == syms.stringType.tsym) { |
1694 | tree.lhs.type = syms.stringType; |
1695 | } |
1696 | if (tree.rhs.type.tsym == syms.stringType.tsym) { |
1697 | tree.rhs.type = syms.stringType; |
1698 | } |
1699 | } |
1700 | } |
1701 | |
1702 | // Check that argument types of a reference ==, != are |
1703 | // castable to each other, (JLS???). |
1704 | if ((opc == ByteCodes.if_acmpeq || opc == ByteCodes.if_acmpne)) { |
1705 | if (!types.isCastable(left, right, new Warner(tree.pos()))) { |
1706 | log.error(tree.pos(), "incomparable.types", left, right); |
1707 | } |
1708 | } |
1709 | |
1710 | chk.checkDivZero(tree.rhs.pos(), operator, right); |
1711 | } |
1712 | result = check(tree, owntype, VAL, pkind, pt); |
1713 | } |
1714 | |
1715 | public void visitTypeCast(JCTypeCast tree) { |
1716 | Type clazztype = attribType(tree.clazz, env); |
1717 | Type exprtype = attribExpr(tree.expr, env, Infer.anyPoly); |
1718 | Type owntype = chk.checkCastable(tree.expr.pos(), exprtype, clazztype); |
1719 | if (exprtype.constValue() != null) |
1720 | owntype = cfolder.coerce(exprtype, owntype); |
1721 | result = check(tree, capture(owntype), VAL, pkind, pt); |
1722 | } |
1723 | |
1724 | public void visitTypeTest(JCInstanceOf tree) { |
1725 | Type exprtype = chk.checkNullOrRefType( |
1726 | tree.expr.pos(), attribExpr(tree.expr, env)); |
1727 | Type clazztype = chk.checkReifiableReferenceType( |
1728 | tree.clazz.pos(), attribType(tree.clazz, env)); |
1729 | chk.checkCastable(tree.expr.pos(), exprtype, clazztype); |
1730 | result = check(tree, syms.booleanType, VAL, pkind, pt); |
1731 | } |
1732 | |
1733 | public void visitIndexed(JCArrayAccess tree) { |
1734 | Type owntype = syms.errType; |
1735 | Type atype = attribExpr(tree.indexed, env); |
1736 | attribExpr(tree.index, env, syms.intType); |
1737 | if (types.isArray(atype)) |
1738 | owntype = types.elemtype(atype); |
1739 | else if (atype.tag != ERROR) |
1740 | log.error(tree.pos(), "array.req.but.found", atype); |
1741 | if ((pkind & VAR) == 0) owntype = capture(owntype); |
1742 | result = check(tree, owntype, VAR, pkind, pt); |
1743 | } |
1744 | |
1745 | public void visitIdent(JCIdent tree) { |
1746 | Symbol sym; |
1747 | boolean varArgs = false; |
1748 | |
1749 | // Find symbol |
1750 | if (pt.tag == METHOD || pt.tag == FORALL) { |
1751 | // If we are looking for a method, the prototype `pt' will be a |
1752 | // method type with the type of the call's arguments as parameters. |
1753 | env.info.varArgs = false; |
1754 | sym = rs.resolveMethod(tree.pos(), env, tree.name, pt.getParameterTypes(), pt.getTypeArguments()); |
1755 | varArgs = env.info.varArgs; |
1756 | } else if (tree.sym != null && tree.sym.kind != VAR) { |
1757 | sym = tree.sym; |
1758 | } else { |
1759 | sym = rs.resolveIdent(tree.pos(), env, tree.name, pkind); |
1760 | } |
1761 | tree.sym = sym; |
1762 | |
1763 | // (1) Also find the environment current for the class where |
1764 | // sym is defined (`symEnv'). |
1765 | // Only for pre-tiger versions (1.4 and earlier): |
1766 | // (2) Also determine whether we access symbol out of an anonymous |
1767 | // class in a this or super call. This is illegal for instance |
1768 | // members since such classes don't carry a this$n link. |
1769 | // (`noOuterThisPath'). |
1770 | Env<AttrContext> symEnv = env; |
1771 | boolean noOuterThisPath = false; |
1772 | if (env.enclClass.sym.owner.kind != PCK && // we are in an inner class |
1773 | (sym.kind & (VAR | MTH | TYP)) != 0 && |
1774 | sym.owner.kind == TYP && |
1775 | tree.name != names._this && tree.name != names._super) { |
1776 | |
1777 | // Find environment in which identifier is defined. |
1778 | while (symEnv.outer != null && |
1779 | !sym.isMemberOf(symEnv.enclClass.sym, types)) { |
1780 | if ((symEnv.enclClass.sym.flags() & NOOUTERTHIS) != 0) |
1781 | noOuterThisPath = !allowAnonOuterThis; |
1782 | symEnv = symEnv.outer; |
1783 | } |
1784 | } |
1785 | |
1786 | // If symbol is a variable, ... |
1787 | if (sym.kind == VAR) { |
1788 | VarSymbol v = (VarSymbol)sym; |
1789 | |
1790 | // ..., evaluate its initializer, if it has one, and check for |
1791 | // illegal forward reference. |
1792 | checkInit(tree, env, v, false); |
1793 | |
1794 | // If symbol is a local variable accessed from an embedded |
1795 | // inner class check that it is final. |
1796 | if (v.owner.kind == MTH && |
1797 | v.owner != env.info.scope.owner && |
1798 | (v.flags_field & FINAL) == 0) { |
1799 | log.error(tree.pos(), |
1800 | "local.var.accessed.from.icls.needs.final", |
1801 | v); |
1802 | } |
1803 | |
1804 | // If we are expecting a variable (as opposed to a value), check |
1805 | // that the variable is assignable in the current environment. |
1806 | if (pkind == VAR) |
1807 | checkAssignable(tree.pos(), v, null, env); |
1808 | } |
1809 | |
1810 | // In a constructor body, |
1811 | // if symbol is a field or instance method, check that it is |
1812 | // not accessed before the supertype constructor is called. |
1813 | if ((symEnv.info.isSelfCall || noOuterThisPath) && |
1814 | (sym.kind & (VAR | MTH)) != 0 && |
1815 | sym.owner.kind == TYP && |
1816 | (sym.flags() & STATIC) == 0) { |
1817 | chk.earlyRefError(tree.pos(), sym.kind == VAR ? sym : thisSym(tree.pos(), env)); |
1818 | } |
1819 | Env<AttrContext> env1 = env; |
1820 | if (sym.kind != ERR && sym.owner != null && sym.owner != env1.enclClass.sym) { |
1821 | // If the found symbol is inaccessible, then it is |
1822 | // accessed through an enclosing instance. Locate this |
1823 | // enclosing instance: |
1824 | while (env1.outer != null && !rs.isAccessible(env, env1.enclClass.sym.type, sym)) |
1825 | env1 = env1.outer; |
1826 | } |
1827 | result = checkId(tree, env1.enclClass.sym.type, sym, env, pkind, pt, varArgs); |
1828 | } |
1829 | |
1830 | public void visitSelect(JCFieldAccess tree) { |
1831 | // Determine the expected kind of the qualifier expression. |
1832 | int skind = 0; |
1833 | if (tree.name == names._this || tree.name == names._super || |
1834 | tree.name == names._class) |
1835 | { |
1836 | skind = TYP; |
1837 | } else { |
1838 | if ((pkind & PCK) != 0) skind = skind | PCK; |
1839 | if ((pkind & TYP) != 0) skind = skind | TYP | PCK; |
1840 | if ((pkind & (VAL | MTH)) != 0) skind = skind | VAL | TYP; |
1841 | } |
1842 | |
1843 | // Attribute the qualifier expression, and determine its symbol (if any). |
1844 | Type site = attribTree(tree.selected, env, skind, Infer.anyPoly); |
1845 | if ((pkind & (PCK | TYP)) == 0) |
1846 | site = capture(site); // Capture field access |
1847 | |
1848 | // don't allow T.class T[].class, etc |
1849 | if (skind == TYP) { |
1850 | Type elt = site; |
1851 | while (elt.tag == ARRAY) |
1852 | elt = ((ArrayType)elt).elemtype; |
1853 | if (elt.tag == TYPEVAR) { |
1854 | log.error(tree.pos(), "type.var.cant.be.deref"); |
1855 | result = syms.errType; |
1856 | return; |
1857 | } |
1858 | } |
1859 | |
1860 | // If qualifier symbol is a type or `super', assert `selectSuper' |
1861 | // for the selection. This is relevant for determining whether |
1862 | // protected symbols are accessible. |
1863 | Symbol sitesym = TreeInfo.symbol(tree.selected); |
1864 | boolean selectSuperPrev = env.info.selectSuper; |
1865 | env.info.selectSuper = |
1866 | sitesym != null && |
1867 | sitesym.name == names._super; |
1868 | |
1869 | // If selected expression is polymorphic, strip |
1870 | // type parameters and remember in env.info.tvars, so that |
1871 | // they can be added later (in Attr.checkId and Infer.instantiateMethod). |
1872 | if (tree.selected.type.tag == FORALL) { |
1873 | ForAll pstype = (ForAll)tree.selected.type; |
1874 | env.info.tvars = pstype.tvars; |
1875 | site = tree.selected.type = pstype.qtype; |
1876 | } |
1877 | |
1878 | // Determine the symbol represented by the selection. |
1879 | env.info.varArgs = false; |
1880 | Symbol sym = selectSym(tree, site, env, pt, pkind); |
1881 | if (sym.exists() && !isType(sym) && (pkind & (PCK | TYP)) != 0) { |
1882 | site = capture(site); |
1883 | sym = selectSym(tree, site, env, pt, pkind); |
1884 | } |
1885 | boolean varArgs = env.info.varArgs; |
1886 | tree.sym = sym; |
1887 | |
1888 | if (site.tag == TYPEVAR && !isType(sym) && sym.kind != ERR) |
1889 | site = capture(site.getUpperBound()); |
1890 | |
1891 | // If that symbol is a variable, ... |
1892 | if (sym.kind == VAR) { |
1893 | VarSymbol v = (VarSymbol)sym; |
1894 | |
1895 | // ..., evaluate its initializer, if it has one, and check for |
1896 | // illegal forward reference. |
1897 | checkInit(tree, env, v, true); |
1898 | |
1899 | // If we are expecting a variable (as opposed to a value), check |
1900 | // that the variable is assignable in the current environment. |
1901 | if (pkind == VAR) |
1902 | checkAssignable(tree.pos(), v, tree.selected, env); |
1903 | } |
1904 | |
1905 | // Disallow selecting a type from an expression |
1906 | if (isType(sym) && (sitesym==null || (sitesym.kind&(TYP|PCK)) == 0)) { |
1907 | tree.type = check(tree.selected, pt, |
1908 | sitesym == null ? VAL : sitesym.kind, TYP|PCK, pt); |
1909 | } |
1910 | |
1911 | if (isType(sitesym)) { |
1912 | if (sym.name == names._this) { |
1913 | // If `C' is the currently compiled class, check that |
1914 | // C.this' does not appear in a call to a super(...) |
1915 | if (env.info.isSelfCall && |
1916 | site.tsym == env.enclClass.sym) { |
1917 | chk.earlyRefError(tree.pos(), sym); |
1918 | } |
1919 | } else { |
1920 | // Check if type-qualified fields or methods are static (JLS) |
1921 | if ((sym.flags() & STATIC) == 0 && |
1922 | sym.name != names._super && |
1923 | (sym.kind == VAR || sym.kind == MTH)) { |
1924 | rs.access(rs.new StaticError(sym), |
1925 | tree.pos(), site, sym.name, true); |
1926 | } |
1927 | } |
1928 | } |
1929 | |
1930 | // If we are selecting an instance member via a `super', ... |
1931 | if (env.info.selectSuper && (sym.flags() & STATIC) == 0) { |
1932 | |
1933 | // Check that super-qualified symbols are not abstract (JLS) |
1934 | rs.checkNonAbstract(tree.pos(), sym); |
1935 | |
1936 | if (site.isRaw()) { |
1937 | // Determine argument types for site. |
1938 | Type site1 = types.asSuper(env.enclClass.sym.type, site.tsym); |
1939 | if (site1 != null) site = site1; |
1940 | } |
1941 | } |
1942 | |
1943 | env.info.selectSuper = selectSuperPrev; |
1944 | result = checkId(tree, site, sym, env, pkind, pt, varArgs); |
1945 | env.info.tvars = List.nil(); |
1946 | } |
1947 | //where |
1948 | /** Determine symbol referenced by a Select expression, |
1949 | * |
1950 | * @param tree The select tree. |
1951 | * @param site The type of the selected expression, |
1952 | * @param env The current environment. |
1953 | * @param pt The current prototype. |
1954 | * @param pkind The expected kind(s) of the Select expression. |
1955 | */ |
1956 | private Symbol selectSym(JCFieldAccess tree, |
1957 | Type site, |
1958 | Env<AttrContext> env, |
1959 | Type pt, |
1960 | int pkind) { |
1961 | DiagnosticPosition pos = tree.pos(); |
1962 | Name name = tree.name; |
1963 | |
1964 | switch (site.tag) { |
1965 | case PACKAGE: |
1966 | return rs.access( |
1967 | rs.findIdentInPackage(env, site.tsym, name, pkind), |
1968 | pos, site, name, true); |
1969 | case ARRAY: |
1970 | case CLASS: |
1971 | if (pt.tag == METHOD || pt.tag == FORALL) { |
1972 | return rs.resolveQualifiedMethod( |
1973 | pos, env, site, name, pt.getParameterTypes(), pt.getTypeArguments()); |
1974 | } else if (name == names._this || name == names._super) { |
1975 | return rs.resolveSelf(pos, env, site.tsym, name); |
1976 | } else if (name == names._class) { |
1977 | // In this case, we have already made sure in |
1978 | // visitSelect that qualifier expression is a type. |
1979 | Type t = syms.classType; |
1980 | List<Type> typeargs = allowGenerics |
1981 | ? List.of(types.erasure(site)) |
1982 | : List.<Type>nil(); |
1983 | t = new ClassType(t.getEnclosingType(), typeargs, t.tsym); |
1984 | return new VarSymbol( |
1985 | STATIC | PUBLIC | FINAL, names._class, t, site.tsym); |
1986 | } else { |
1987 | // We are seeing a plain identifier as selector. |
1988 | Symbol sym = rs.findIdentInType(env, site, name, pkind); |
1989 | if ((pkind & ERRONEOUS) == 0) |
1990 | sym = rs.access(sym, pos, site, name, true); |
1991 | return sym; |
1992 | } |
1993 | case WILDCARD: |
1994 | throw new AssertionError(tree); |
1995 | case TYPEVAR: |
1996 | // Normally, site.getUpperBound() shouldn't be null. |
1997 | // It should only happen during memberEnter/attribBase |
1998 | // when determining the super type which *must* be |
1999 | // done before attributing the type variables. In |
2000 | // other words, we are seeing this illegal program: |
2001 | // class B<T> extends A<T.foo> {} |
2002 | Symbol sym = (site.getUpperBound() != null) |
2003 | ? selectSym(tree, capture(site.getUpperBound()), env, pt, pkind) |
2004 | : null; |
2005 | if (sym == null || isType(sym)) { |
2006 | log.error(pos, "type.var.cant.be.deref"); |
2007 | return syms.errSymbol; |
2008 | } else { |
2009 | return sym; |
2010 | } |
2011 | case ERROR: |
2012 | // preserve identifier names through errors |
2013 | return new ErrorType(name, site.tsym).tsym; |
2014 | default: |
2015 | // The qualifier expression is of a primitive type -- only |
2016 | // .class is allowed for these. |
2017 | if (name == names._class) { |
2018 | // In this case, we have already made sure in Select that |
2019 | // qualifier expression is a type. |
2020 | Type t = syms.classType; |
2021 | Type arg = types.boxedClass(site).type; |
2022 | t = new ClassType(t.getEnclosingType(), List.of(arg), t.tsym); |
2023 | return new VarSymbol( |
2024 | STATIC | PUBLIC | FINAL, names._class, t, site.tsym); |
2025 | } else { |
2026 | log.error(pos, "cant.deref", site); |
2027 | return syms.errSymbol; |
2028 | } |
2029 | } |
2030 | } |
2031 | |
2032 | /** Determine type of identifier or select expression and check that |
2033 | * (1) the referenced symbol is not deprecated |
2034 | * (2) the symbol's type is safe (@see checkSafe) |
2035 | * (3) if symbol is a variable, check that its type and kind are |
2036 | * compatible with the prototype and protokind. |
2037 | * (4) if symbol is an instance field of a raw type, |
2038 | * which is being assigned to, issue an unchecked warning if its |
2039 | * type changes under erasure. |
2040 | * (5) if symbol is an instance method of a raw type, issue an |
2041 | * unchecked warning if its argument types change under erasure. |
2042 | * If checks succeed: |
2043 | * If symbol is a constant, return its constant type |
2044 | * else if symbol is a method, return its result type |
2045 | * otherwise return its type. |
2046 | * Otherwise return errType. |
2047 | * |
2048 | * @param tree The syntax tree representing the identifier |
2049 | * @param site If this is a select, the type of the selected |
2050 | * expression, otherwise the type of the current class. |
2051 | * @param sym The symbol representing the identifier. |
2052 | * @param env The current environment. |
2053 | * @param pkind The set of expected kinds. |
2054 | * @param pt The expected type. |
2055 | */ |
2056 | Type checkId(JCTree tree, |
2057 | Type site, |
2058 | Symbol sym, |
2059 | Env<AttrContext> env, |
2060 | int pkind, |
2061 | Type pt, |
2062 | boolean useVarargs) { |
2063 | if (pt.isErroneous()) return syms.errType; |
2064 | Type owntype; // The computed type of this identifier occurrence. |
2065 | switch (sym.kind) { |
2066 | case TYP: |
2067 | // For types, the computed type equals the symbol's type, |
2068 | // except for two situations: |
2069 | owntype = sym.type; |
2070 | if (owntype.tag == CLASS) { |
2071 | Type ownOuter = owntype.getEnclosingType(); |
2072 | |
2073 | // (a) If the symbol's type is parameterized, erase it |
2074 | // because no type parameters were given. |
2075 | // We recover generic outer type later in visitTypeApply. |
2076 | if (owntype.tsym.type.getTypeArguments().nonEmpty()) { |
2077 | owntype = types.erasure(owntype); |
2078 | } |
2079 | |
2080 | // (b) If the symbol's type is an inner class, then |
2081 | // we have to interpret its outer type as a superclass |
2082 | // of the site type. Example: |
2083 | // |
2084 | // class Tree<A> { class Visitor { ... } } |
2085 | // class PointTree extends Tree<Point> { ... } |
2086 | // ...PointTree.Visitor... |
2087 | // |
2088 | // Then the type of the last expression above is |
2089 | // Tree<Point>.Visitor. |
2090 | else if (ownOuter.tag == CLASS && site != ownOuter) { |
2091 | Type normOuter = site; |
2092 | if (normOuter.tag == CLASS) |
2093 | normOuter = types.asEnclosingSuper(site, ownOuter.tsym); |
2094 | if (normOuter == null) // perhaps from an import |
2095 | normOuter = types.erasure(ownOuter); |
2096 | if (normOuter != ownOuter) |
2097 | owntype = new ClassType( |
2098 | normOuter, List.<Type>nil(), owntype.tsym); |
2099 | } |
2100 | } |
2101 | break; |
2102 | case VAR: |
2103 | VarSymbol v = (VarSymbol)sym; |
2104 | // Test (4): if symbol is an instance field of a raw type, |
2105 | // which is being assigned to, issue an unchecked warning if |
2106 | // its type changes under erasure. |
2107 | if (allowGenerics && |
2108 | pkind == VAR && |
2109 | v.owner.kind == TYP && |
2110 | (v.flags() & STATIC) == 0 && |
2111 | (site.tag == CLASS || site.tag == TYPEVAR)) { |
2112 | Type s = types.asOuterSuper(site, v.owner); |
2113 | if (s != null && |
2114 | s.isRaw() && |
2115 | !types.isSameType(v.type, v.erasure(types))) { |
2116 | chk.warnUnchecked(tree.pos(), |
2117 | "unchecked.assign.to.var", |
2118 | v, s); |
2119 | } |
2120 | } |
2121 | // The computed type of a variable is the type of the |
2122 | // variable symbol, taken as a member of the site type. |
2123 | owntype = (sym.owner.kind == TYP && |
2124 | sym.name != names._this && sym.name != names._super) |
2125 | ? types.memberType(site, sym) |
2126 | : sym.type; |
2127 | |
2128 | if (env.info.tvars.nonEmpty()) { |
2129 | Type owntype1 = new ForAll(env.info.tvars, owntype); |
2130 | for (List<Type> l = env.info.tvars; l.nonEmpty(); l = l.tail) |
2131 | if (!owntype.contains(l.head)) { |
2132 | log.error(tree.pos(), "undetermined.type", owntype1); |
2133 | owntype1 = syms.errType; |
2134 | } |
2135 | owntype = owntype1; |
2136 | } |
2137 | |
2138 | // If the variable is a constant, record constant value in |
2139 | // computed type. |
2140 | if (v.getConstValue() != null && isStaticReference(tree)) |
2141 | owntype = owntype.constType(v.getConstValue()); |
2142 | |
2143 | if (pkind == VAL) { |
2144 | owntype = capture(owntype); // capture "names as expressions" |
2145 | } |
2146 | break; |
2147 | case MTH: { |
2148 | JCMethodInvocation app = (JCMethodInvocation)env.tree; |
2149 | owntype = checkMethod(site, sym, env, app.args, |
2150 | pt.getParameterTypes(), pt.getTypeArguments(), |
2151 | env.info.varArgs); |
2152 | break; |
2153 | } |
2154 | case PCK: case ERR: |
2155 | owntype = sym.type; |
2156 | break; |
2157 | default: |
2158 | throw new AssertionError("unexpected kind: " + sym.kind + |
2159 | " in tree " + tree); |
2160 | } |
2161 | |
2162 | // Test (1): emit a `deprecation' warning if symbol is deprecated. |
2163 | // (for constructors, the error was given when the constructor was |
2164 | // resolved) |
2165 | if (sym.name != names.init && |
2166 | (sym.flags() & DEPRECATED) != 0 && |
2167 | (env.info.scope.owner.flags() & DEPRECATED) == 0 && |
2168 | sym.outermostClass() != env.info.scope.owner.outermostClass()) |
2169 | chk.warnDeprecated(tree.pos(), sym); |
2170 | |
2171 | if ((sym.flags() & PROPRIETARY) != 0) |
2172 | log.strictWarning(tree.pos(), "sun.proprietary", sym); |
2173 | |
2174 | // Test (3): if symbol is a variable, check that its type and |
2175 | // kind are compatible with the prototype and protokind. |
2176 | return check(tree, owntype, sym.kind, pkind, pt); |
2177 | } |
2178 | |
2179 | /** Check that variable is initialized and evaluate the variable's |
2180 | * initializer, if not yet done. Also check that variable is not |
2181 | * referenced before it is defined. |
2182 | * @param tree The tree making up the variable reference. |
2183 | * @param env The current environment. |
2184 | * @param v The variable's symbol. |
2185 | */ |
2186 | private void checkInit(JCTree tree, |
2187 | Env<AttrContext> env, |
2188 | VarSymbol v, |
2189 | boolean onlyWarning) { |
2190 | // System.err.println(v + " " + ((v.flags() & STATIC) != 0) + " " + |
2191 | // tree.pos + " " + v.pos + " " + |
2192 | // Resolve.isStatic(env));//DEBUG |
2193 | |
2194 | // A forward reference is diagnosed if the declaration position |
2195 | // of the variable is greater than the current tree position |
2196 | // and the tree and variable definition occur in the same class |
2197 | // definition. Note that writes don't count as references. |
2198 | // This check applies only to class and instance |
2199 | // variables. Local variables follow different scope rules, |
2200 | // and are subject to definite assignment checking. |
2201 | if (v.pos > tree.pos && |
2202 | v.owner.kind == TYP && |
2203 | canOwnInitializer(env.info.scope.owner) && |
2204 | v.owner == env.info.scope.owner.enclClass() && |
2205 | ((v.flags() & STATIC) != 0) == Resolve.isStatic(env) && |
2206 | (env.tree.getTag() != JCTree.ASSIGN || |
2207 | TreeInfo.skipParens(((JCAssign) env.tree).lhs) != tree)) { |
2208 | |
2209 | if (!onlyWarning || isNonStaticEnumField(v)) { |
2210 | log.error(tree.pos(), "illegal.forward.ref"); |
2211 | } else if (useBeforeDeclarationWarning) { |
2212 | log.warning(tree.pos(), "forward.ref", v); |
2213 | } |
2214 | } |
2215 | |
2216 | v.getConstValue(); // ensure initializer is evaluated |
2217 | |
2218 | checkEnumInitializer(tree, env, v); |
2219 | } |
2220 | |
2221 | /** |
2222 | * Check for illegal references to static members of enum. In |
2223 | * an enum type, constructors and initializers may not |
2224 | * reference its static members unless they are constant. |
2225 | * |
2226 | * @param tree The tree making up the variable reference. |
2227 | * @param env The current environment. |
2228 | * @param v The variable's symbol. |
2229 | * @see JLS 3rd Ed. (8.9 Enums) |
2230 | */ |
2231 | private void checkEnumInitializer(JCTree tree, Env<AttrContext> env, VarSymbol v) { |
2232 | // JLS 3rd Ed.: |
2233 | // |
2234 | // "It is a compile-time error to reference a static field |
2235 | // of an enum type that is not a compile-time constant |
2236 | // (15.28) from constructors, instance initializer blocks, |
2237 | // or instance variable initializer expressions of that |
2238 | // type. It is a compile-time error for the constructors, |
2239 | // instance initializer blocks, or instance variable |
2240 | // initializer expressions of an enum constant e to refer |
2241 | // to itself or to an enum constant of the same type that |
2242 | // is declared to the right of e." |
2243 | if (isNonStaticEnumField(v)) { |
2244 | ClassSymbol enclClass = env.info.scope.owner.enclClass(); |
2245 | |
2246 | if (enclClass == null || enclClass.owner == null) |
2247 | return; |
2248 | |
2249 | // See if the enclosing class is the enum (or a |
2250 | // subclass thereof) declaring v. If not, this |
2251 | // reference is OK. |
2252 | if (v.owner != enclClass && !types.isSubtype(enclClass.type, v.owner.type)) |
2253 | return; |
2254 | |
2255 | // If the reference isn't from an initializer, then |
2256 | // the reference is OK. |
2257 | if (!Resolve.isInitializer(env)) |
2258 | return; |
2259 | |
2260 | log.error(tree.pos(), "illegal.enum.static.ref"); |
2261 | } |
2262 | } |
2263 | |
2264 | private boolean isNonStaticEnumField(VarSymbol v) { |
2265 | return Flags.isEnum(v.owner) && Flags.isStatic(v) && !Flags.isConstant(v); |
2266 | } |
2267 | |
2268 | /** Can the given symbol be the owner of code which forms part |
2269 | * if class initialization? This is the case if the symbol is |
2270 | * a type or field, or if the symbol is the synthetic method. |
2271 | * owning a block. |
2272 | */ |
2273 | private boolean canOwnInitializer(Symbol sym) { |
2274 | return |
2275 | (sym.kind & (VAR | TYP)) != 0 || |
2276 | (sym.kind == MTH && (sym.flags() & BLOCK) != 0); |
2277 | } |
2278 | |
2279 | Warner noteWarner = new Warner(); |
2280 | |
2281 | /** |
2282 | * Check that method arguments conform to its instantation. |
2283 | **/ |
2284 | public Type checkMethod(Type site, |
2285 | Symbol sym, |
2286 | Env<AttrContext> env, |
2287 | final List<JCExpression> argtrees, |
2288 | List<Type> argtypes, |
2289 | List<Type> typeargtypes, |
2290 | boolean useVarargs) { |
2291 | // Test (5): if symbol is an instance method of a raw type, issue |
2292 | // an unchecked warning if its argument types change under erasure. |
2293 | if (allowGenerics && |
2294 | (sym.flags() & STATIC) == 0 && |
2295 | (site.tag == CLASS || site.tag == TYPEVAR)) { |
2296 | Type s = types.asOuterSuper(site, sym.owner); |
2297 | if (s != null && s.isRaw() && |
2298 | !types.isSameTypes(sym.type.getParameterTypes(), |
2299 | sym.erasure(types).getParameterTypes())) { |
2300 | chk.warnUnchecked(env.tree.pos(), |
2301 | "unchecked.call.mbr.of.raw.type", |
2302 | sym, s); |
2303 | } |
2304 | } |
2305 | |
2306 | // Compute the identifier's instantiated type. |
2307 | // For methods, we need to compute the instance type by |
2308 | // Resolve.instantiate from the symbol's type as well as |
2309 | // any type arguments and value arguments. |
2310 | noteWarner.warned = false; |
2311 | Type owntype = rs.instantiate(env, |
2312 | site, |
2313 | sym, |
2314 | argtypes, |
2315 | typeargtypes, |
2316 | true, |
2317 | useVarargs, |
2318 | noteWarner); |
2319 | boolean warned = noteWarner.warned; |
2320 | |
2321 | // If this fails, something went wrong; we should not have |
2322 | // found the identifier in the first place. |
2323 | if (owntype == null) { |
2324 | if (!pt.isErroneous()) |
2325 | log.error(env.tree.pos(), |
2326 | "internal.error.cant.instantiate", |
2327 | sym, site, |
2328 | Type.toString(pt.getParameterTypes())); |
2329 | owntype = syms.errType; |
2330 | } else { |
2331 | // System.out.println("call : " + env.tree); |
2332 | // System.out.println("method : " + owntype); |
2333 | // System.out.println("actuals: " + argtypes); |
2334 | List<Type> formals = owntype.getParameterTypes(); |
2335 | Type last = useVarargs ? formals.last() : null; |
2336 | if (sym.name==names.init && |
2337 | sym.owner == syms.enumSym) |
2338 | formals = formals.tail.tail; |
2339 | List<JCExpression> args = argtrees; |
2340 | while (formals.head != last) { |
2341 | JCTree arg = args.head; |
2342 | Warner warn = chk.convertWarner(arg.pos(), arg.type, formals.head); |
2343 | assertConvertible(arg, arg.type, formals.head, warn); |
2344 | warned |= warn.warned; |
2345 | args = args.tail; |
2346 | formals = formals.tail; |
2347 | } |
2348 | if (useVarargs) { |
2349 | Type varArg = types.elemtype(last); |
2350 | while (args.tail != null) { |
2351 | JCTree arg = args.head; |
2352 | Warner warn = chk.convertWarner(arg.pos(), arg.type, varArg); |
2353 | assertConvertible(arg, arg.type, varArg, warn); |
2354 | warned |= warn.warned; |
2355 | args = args.tail; |
2356 | } |
2357 | } else if ((sym.flags() & VARARGS) != 0 && allowVarargs) { |
2358 | // non-varargs call to varargs method |
2359 | Type varParam = owntype.getParameterTypes().last(); |
2360 | Type lastArg = argtypes.last(); |
2361 | if (types.isSubtypeUnchecked(lastArg, types.elemtype(varParam)) && |
2362 | !types.isSameType(types.erasure(varParam), types.erasure(lastArg))) |
2363 | log.warning(argtrees.last().pos(), "inexact.non-varargs.call", |
2364 | types.elemtype(varParam), |
2365 | varParam); |
2366 | } |
2367 | |
2368 | if (warned && sym.type.tag == FORALL) { |
2369 | String typeargs = ""; |
2370 | if (typeargtypes != null && typeargtypes.nonEmpty()) { |
2371 | typeargs = "<" + Type.toString(typeargtypes) + ">"; |
2372 | } |
2373 | chk.warnUnchecked(env.tree.pos(), |
2374 | "unchecked.meth.invocation.applied", |
2375 | sym, |
2376 | sym.location(), |
2377 | typeargs, |
2378 | Type.toString(argtypes)); |
2379 | owntype = new MethodType(owntype.getParameterTypes(), |
2380 | types.erasure(owntype.getReturnType()), |
2381 | owntype.getThrownTypes(), |
2382 | syms.methodClass); |
2383 | } |
2384 | if (useVarargs) { |
2385 | JCTree tree = env.tree; |
2386 | Type argtype = owntype.getParameterTypes().last(); |
2387 | if (!types.isReifiable(argtype)) |
2388 | chk.warnUnchecked(env.tree.pos(), |
2389 | "unchecked.generic.array.creation", |
2390 | argtype); |
2391 | Type elemtype = types.elemtype(argtype); |
2392 | switch (tree.getTag()) { |
2393 | case JCTree.APPLY: |
2394 | ((JCMethodInvocation) tree).varargsElement = elemtype; |
2395 | break; |
2396 | case JCTree.NEWCLASS: |
2397 | ((JCNewClass) tree).varargsElement = elemtype; |
2398 | break; |
2399 | default: |
2400 | throw new AssertionError(""+tree); |
2401 | } |
2402 | } |
2403 | } |
2404 | return owntype; |
2405 | } |
2406 | |
2407 | private void assertConvertible(JCTree tree, Type actual, Type formal, Warner warn) { |
2408 | if (types.isConvertible(actual, formal, warn)) |
2409 | return; |
2410 | |
2411 | if (formal.isCompound() |
2412 | && types.isSubtype(actual, types.supertype(formal)) |
2413 | && types.isSubtypeUnchecked(actual, types.interfaces(formal), warn)) |
2414 | return; |
2415 | |
2416 | if (false) { |
2417 | // TODO: make assertConvertible work |
2418 | chk.typeError(tree.pos(), JCDiagnostic.fragment("incompatible.types"), actual, formal); |
2419 | throw new AssertionError("Tree: " + tree |
2420 | + " actual:" + actual |
2421 | + " formal: " + formal); |
2422 | } |
2423 | } |
2424 | |
2425 | public void visitLiteral(JCLiteral tree) { |
2426 | result = check( |
2427 | tree, litType(tree.typetag).constType(tree.value), VAL, pkind, pt); |
2428 | } |
2429 | //where |
2430 | /** Return the type of a literal with given type tag. |
2431 | */ |
2432 | Type litType(int tag) { |
2433 | return (tag == TypeTags.CLASS) ? syms.stringType : syms.typeOfTag[tag]; |
2434 | } |
2435 | |
2436 | public void visitTypeIdent(JCPrimitiveTypeTree tree) { |
2437 | result = check(tree, syms.typeOfTag[tree.typetag], TYP, pkind, pt); |
2438 | } |
2439 | |
2440 | public void visitTypeArray(JCArrayTypeTree tree) { |
2441 | Type etype = attribType(tree.elemtype, env); |
2442 | Type type = new ArrayType(etype, syms.arrayClass); |
2443 | result = check(tree, type, TYP, pkind, pt); |
2444 | } |
2445 | |
2446 | /** Visitor method for parameterized types. |
2447 | * Bound checking is left until later, since types are attributed |
2448 | * before supertype structure is completely known |
2449 | */ |
2450 | public void visitTypeApply(JCTypeApply tree) { |
2451 | Type owntype = syms.errType; |
2452 | |
2453 | // Attribute functor part of application and make sure it's a class. |
2454 | Type clazztype = chk.checkClassType(tree.clazz.pos(), attribType(tree.clazz, env)); |
2455 | |
2456 | // Attribute type parameters |
2457 | List<Type> actuals = attribTypes(tree.arguments, env); |
2458 | |
2459 | if (clazztype.tag == CLASS) { |
2460 | List<Type> formals = clazztype.tsym.type.getTypeArguments(); |
2461 | |
2462 | if (actuals.length() == formals.length()) { |
2463 | List<Type> a = actuals; |
2464 | List<Type> f = formals; |
2465 | while (a.nonEmpty()) { |
2466 | a.head = a.head.withTypeVar(f.head); |
2467 | a = a.tail; |
2468 | f = f.tail; |
2469 | } |
2470 | // Compute the proper generic outer |
2471 | Type clazzOuter = clazztype.getEnclosingType(); |
2472 | if (clazzOuter.tag == CLASS) { |
2473 | Type site; |
2474 | if (tree.clazz.getTag() == JCTree.IDENT) { |
2475 | site = env.enclClass.sym.type; |
2476 | } else if (tree.clazz.getTag() == JCTree.SELECT) { |
2477 | site = ((JCFieldAccess) tree.clazz).selected.type; |
2478 | } else throw new AssertionError(""+tree); |
2479 | if (clazzOuter.tag == CLASS && site != clazzOuter) { |
2480 | if (site.tag == CLASS) |
2481 | site = types.asOuterSuper(site, clazzOuter.tsym); |
2482 | if (site == null) |
2483 | site = types.erasure(clazzOuter); |
2484 | clazzOuter = site; |
2485 | } |
2486 | } |
2487 | owntype = new ClassType(clazzOuter, actuals, clazztype.tsym); |
2488 | } else { |
2489 | if (formals.length() != 0) { |
2490 | log.error(tree.pos(), "wrong.number.type.args", |
2491 | Integer.toString(formals.length())); |
2492 | } else { |
2493 | log.error(tree.pos(), "type.doesnt.take.params", clazztype.tsym); |
2494 | } |
2495 | owntype = syms.errType; |
2496 | } |
2497 | } |
2498 | result = check(tree, owntype, TYP, pkind, pt); |
2499 | } |
2500 | |
2501 | public void visitTypeParameter(JCTypeParameter tree) { |
2502 | TypeVar a = (TypeVar)tree.type; |
2503 | Set<Type> boundSet = new HashSet<Type>(); |
2504 | if (a.bound.isErroneous()) |
2505 | return; |
2506 | List<Type> bs = types.getBounds(a); |
2507 | if (tree.bounds.nonEmpty()) { |
2508 | // accept class or interface or typevar as first bound. |
2509 | Type b = checkBase(bs.head, tree.bounds.head, env, false, false, false); |
2510 | boundSet.add(types.erasure(b)); |
2511 | if (b.tag == TYPEVAR) { |
2512 | // if first bound was a typevar, do not accept further bounds. |
2513 | if (tree.bounds.tail.nonEmpty()) { |
2514 | log.error(tree.bounds.tail.head.pos(), |
2515 | "type.var.may.not.be.followed.by.other.bounds"); |
2516 | tree.bounds = List.of(tree.bounds.head); |
2517 | } |
2518 | } else { |
2519 | // if first bound was a class or interface, accept only interfaces |
2520 | // as further bounds. |
2521 | for (JCExpression bound : tree.bounds.tail) { |
2522 | bs = bs.tail; |
2523 | Type i = checkBase(bs.head, bound, env, false, true, false); |
2524 | if (i.tag == CLASS) |
2525 | chk.checkNotRepeated(bound.pos(), types.erasure(i), boundSet); |
2526 | } |
2527 | } |
2528 | } |
2529 | bs = types.getBounds(a); |
2530 | |
2531 | // in case of multiple bounds ... |
2532 | if (bs.length() > 1) { |
2533 | // ... the variable's bound is a class type flagged COMPOUND |
2534 | // (see comment for TypeVar.bound). |
2535 | // In this case, generate a class tree that represents the |
2536 | // bound class, ... |
2537 | JCTree extending; |
2538 | List<JCExpression> implementing; |
2539 | if ((bs.head.tsym.flags() & INTERFACE) == 0) { |
2540 | extending = tree.bounds.head; |
2541 | implementing = tree.bounds.tail; |
2542 | } else { |
2543 | extending = null; |
2544 | implementing = tree.bounds; |
2545 | } |
2546 | JCClassDecl cd = make.at(tree.pos).ClassDef( |
2547 | make.Modifiers(PUBLIC | ABSTRACT), |
2548 | tree.name, List.<JCTypeParameter>nil(), |
2549 | extending, implementing, List.<JCTree>nil()); |
2550 | |
2551 | ClassSymbol c = (ClassSymbol)a.getUpperBound().tsym; |
2552 | assert (c.flags() & COMPOUND) != 0; |
2553 | cd.sym = c; |
2554 | c.sourcefile = env.toplevel.sourcefile; |
2555 | |
2556 | // ... and attribute the bound class |
2557 | c.flags_field |= UNATTRIBUTED; |
2558 | Env<AttrContext> cenv = enter.classEnv(cd, env); |
2559 | enter.typeEnvs.put(c, cenv); |
2560 | } |
2561 | } |
2562 | |
2563 | |
2564 | public void visitWildcard(JCWildcard tree) { |
2565 | //- System.err.println("visitWildcard("+tree+");");//DEBUG |
2566 | Type type = (tree.kind.kind == BoundKind.UNBOUND) |
2567 | ? syms.objectType |
2568 | : attribType(tree.inner, env); |
2569 | result = check(tree, new WildcardType(chk.checkRefType(tree.pos(), type), |
2570 | tree.kind.kind, |
2571 | syms.boundClass), |
2572 | TYP, pkind, pt); |
2573 | } |
2574 | |
2575 | public void visitAnnotation(JCAnnotation tree) { |
2576 | log.error(tree.pos(), "annotation.not.valid.for.type", pt); |
2577 | result = tree.type = syms.errType; |
2578 | } |
2579 | |
2580 | public void visitErroneous(JCErroneous tree) { |
2581 | if (tree.errs != null) |
2582 | for (JCTree err : tree.errs) |
2583 | attribTree(err, env, ERR, pt); |
2584 | result = tree.type = syms.errType; |
2585 | } |
2586 | |
2587 | /** Default visitor method for all other trees. |
2588 | */ |
2589 | public void visitTree(JCTree tree) { |
2590 | throw new AssertionError(); |
2591 | } |
2592 | |
2593 | /** Main method: attribute class definition associated with given class symbol. |
2594 | * reporting completion failures at the given position. |
2595 | * @param pos The source position at which completion errors are to be |
2596 | * reported. |
2597 | * @param c The class symbol whose definition will be attributed. |
2598 | */ |
2599 | public void attribClass(DiagnosticPosition pos, ClassSymbol c) { |
2600 | try { |
2601 | annotate.flush(); |
2602 | attribClass(c); |
2603 | } catch (CompletionFailure ex) { |
2604 | chk.completionError(pos, ex); |
2605 | } |
2606 | } |
2607 | |
2608 | /** Attribute class definition associated with given class symbol. |
2609 | * @param c The class symbol whose definition will be attributed. |
2610 | */ |
2611 | void attribClass(ClassSymbol c) throws CompletionFailure { |
2612 | if (c.type.tag == ERROR) return; |
2613 | |
2614 | // Check for cycles in the inheritance graph, which can arise from |
2615 | // ill-formed class files. |
2616 | chk.checkNonCyclic(null, c.type); |
2617 | |
2618 | Type st = types.supertype(c.type); |
2619 | if ((c.flags_field & Flags.COMPOUND) == 0) { |
2620 | // First, attribute superclass. |
2621 | if (st.tag == CLASS) |
2622 | attribClass((ClassSymbol)st.tsym); |
2623 | |
2624 | // Next attribute owner, if it is a class. |
2625 | if (c.owner.kind == TYP && c.owner.type.tag == CLASS) |
2626 | attribClass((ClassSymbol)c.owner); |
2627 | } |
2628 | |
2629 | // The previous operations might have attributed the current class |
2630 | // if there was a cycle. So we test first whether the class is still |
2631 | // UNATTRIBUTED. |
2632 | if ((c.flags_field & UNATTRIBUTED) != 0) { |
2633 | c.flags_field &= ~UNATTRIBUTED; |
2634 | |
2635 | // Get environment current at the point of class definition. |
2636 | Env<AttrContext> env = enter.typeEnvs.get(c); |
2637 | |
2638 | // The info.lint field in the envs stored in enter.typeEnvs is deliberately uninitialized, |
2639 | // because the annotations were not available at the time the env was created. Therefore, |
2640 | // we look up the environment chain for the first enclosing environment for which the |
2641 | // lint value is set. Typically, this is the parent env, but might be further if there |
2642 | // are any envs created as a result of TypeParameter nodes. |
2643 | Env<AttrContext> lintEnv = env; |
2644 | while (lintEnv.info.lint == null) |
2645 | lintEnv = lintEnv.next; |
2646 | |
2647 | // Having found the enclosing lint value, we can initialize the lint value for this class |
2648 | env.info.lint = lintEnv.info.lint.augment(c.attributes_field, c.flags()); |
2649 | |
2650 | Lint prevLint = chk.setLint(env.info.lint); |
2651 | JavaFileObject prev = log.useSource(c.sourcefile); |
2652 | |
2653 | try { |
2654 | // java.lang.Enum may not be subclassed by a non-enum |
2655 | if (st.tsym == syms.enumSym && |
2656 | ((c.flags_field & (Flags.ENUM|Flags.COMPOUND)) == 0)) |
2657 | log.error(env.tree.pos(), "enum.no.subclassing"); |
2658 | |
2659 | // Enums may not be extended by source-level classes |
2660 | if (st.tsym != null && |
2661 | ((st.tsym.flags_field & Flags.ENUM) != 0) && |
2662 | ((c.flags_field & Flags.ENUM) == 0) && |
2663 | !target.compilerBootstrap(c)) { |
2664 | log.error(env.tree.pos(), "enum.types.not.extensible"); |
2665 | } |
2666 | attribClassBody(env, c); |
2667 | |
2668 | chk.checkDeprecatedAnnotation(env.tree.pos(), c); |
2669 | } finally { |
2670 | log.useSource(prev); |
2671 | chk.setLint(prevLint); |
2672 | } |
2673 | |
2674 | } |
2675 | } |
2676 | |
2677 | public void visitImport(JCImport tree) { |
2678 | // nothing to do |
2679 | } |
2680 | |
2681 | /** Finish the attribution of a class. */ |
2682 | private void attribClassBody(Env<AttrContext> env, ClassSymbol c) { |
2683 | JCClassDecl tree = (JCClassDecl)env.tree; |
2684 | assert c == tree.sym; |
2685 | |
2686 | // Validate annotations |
2687 | chk.validateAnnotations(tree.mods.annotations, c); |
2688 | |
2689 | // Validate type parameters, supertype and interfaces. |
2690 | attribBounds(tree.typarams); |
2691 | chk.validateTypeParams(tree.typarams); |
2692 | chk.validate(tree.extending); |
2693 | chk.validate(tree.implementing); |
2694 | |
2695 | // If this is a non-abstract class, check that it has no abstract |
2696 | // methods or unimplemented methods of an implemented interface. |
2697 | if ((c.flags() & (ABSTRACT | INTERFACE)) == 0) { |
2698 | if (!relax) |
2699 | chk.checkAllDefined(tree.pos(), c); |
2700 | } |
2701 | |
2702 | if ((c.flags() & ANNOTATION) != 0) { |
2703 | if (tree.implementing.nonEmpty()) |
2704 | log.error(tree.implementing.head.pos(), |
2705 | "cant.extend.intf.annotation"); |
2706 | if (tree.typarams.nonEmpty()) |
2707 | log.error(tree.typarams.head.pos(), |
2708 | "intf.annotation.cant.have.type.params"); |
2709 | } else { |
2710 | // Check that all extended classes and interfaces |
2711 | // are compatible (i.e. no two define methods with same arguments |
2712 | // yet different return types). (JLS 8.4.6.3) |
2713 | chk.checkCompatibleSupertypes(tree.pos(), c.type); |
2714 | } |
2715 | |
2716 | // Check that class does not import the same parameterized interface |
2717 | // with two different argument lists. |
2718 | chk.checkClassBounds(tree.pos(), c.type); |
2719 | |
2720 | tree.type = c.type; |
2721 | |
2722 | boolean assertsEnabled = false; |
2723 | assert assertsEnabled = true; |
2724 | if (assertsEnabled) { |
2725 | for (List<JCTypeParameter> l = tree.typarams; |
2726 | l.nonEmpty(); l = l.tail) |
2727 | assert env.info.scope.lookup(l.head.name).scope != null; |
2728 | } |
2729 | |
2730 | // Check that a generic class doesn't extend Throwable |
2731 | if (!c.type.allparams().isEmpty() && types.isSubtype(c.type, syms.throwableType)) |
2732 | log.error(tree.extending.pos(), "generic.throwable"); |
2733 | |
2734 | // Check that all methods which implement some |
2735 | // method conform to the method they implement. |
2736 | chk.checkImplementations(tree); |
2737 | |
2738 | for (List<JCTree> l = tree.defs; l.nonEmpty(); l = l.tail) { |
2739 | // Attribute declaration |
2740 | attribStat(l.head, env); |
2741 | // Check that declarations in inner classes are not static (JLS 8.1.2) |
2742 | // Make an exception for static constants. |
2743 | if (c.owner.kind != PCK && |
2744 | ((c.flags() & STATIC) == 0 || c.name == names.empty) && |
2745 | (TreeInfo.flags(l.head) & (STATIC | INTERFACE)) != 0) { |
2746 | Symbol sym = null; |
2747 | if (l.head.getTag() == JCTree.VARDEF) sym = ((JCVariableDecl) l.head).sym; |
2748 | if (sym == null || |
2749 | sym.kind != VAR || |
2750 | ((VarSymbol) sym).getConstValue() == null) |
2751 | log.error(l.head.pos(), "icls.cant.have.static.decl"); |
2752 | } |
2753 | } |
2754 | |
2755 | // Check for cycles among non-initial constructors. |
2756 | chk.checkCyclicConstructors(tree); |
2757 | |
2758 | // Check for cycles among annotation elements. |
2759 | chk.checkNonCyclicElements(tree); |
2760 | |
2761 | // Check for proper use of serialVersionUID |
2762 | if (env.info.lint.isEnabled(Lint.LintCategory.SERIAL) && |
2763 | isSerializable(c) && |
2764 | (c.flags() & Flags.ENUM) == 0 && |
2765 | (c.flags() & ABSTRACT) == 0) { |
2766 | checkSerialVersionUID(tree, c); |
2767 | } |
2768 | } |
2769 | // where |
2770 | /** check if a class is a subtype of Serializable, if that is available. */ |
2771 | private boolean isSerializable(ClassSymbol c) { |
2772 | try { |
2773 | syms.serializableType.complete(); |
2774 | } |
2775 | catch (CompletionFailure e) { |
2776 | return false; |
2777 | } |
2778 | return types.isSubtype(c.type, syms.serializableType); |
2779 | } |
2780 | |
2781 | /** Check that an appropriate serialVersionUID member is defined. */ |
2782 | private void checkSerialVersionUID(JCClassDecl tree, ClassSymbol c) { |
2783 | |
2784 | // check for presence of serialVersionUID |
2785 | Scope.Entry e = c.members().lookup(names.serialVersionUID); |
2786 | while (e.scope != null && e.sym.kind != VAR) e = e.next(); |
2787 | if (e.scope == null) { |
2788 | log.warning(tree.pos(), "missing.SVUID", c); |
2789 | return; |
2790 | } |
2791 | |
2792 | // check that it is static final |
2793 | VarSymbol svuid = (VarSymbol)e.sym; |
2794 | if ((svuid.flags() & (STATIC | FINAL)) != |
2795 | (STATIC | FINAL)) |
2796 | log.warning(TreeInfo.diagnosticPositionFor(svuid, tree), "improper.SVUID", c); |
2797 | |
2798 | // check that it is long |
2799 | else if (svuid.type.tag != TypeTags.LONG) |
2800 | log.warning(TreeInfo.diagnosticPositionFor(svuid, tree), "long.SVUID", c); |
2801 | |
2802 | // check constant |
2803 | else if (svuid.getConstValue() == null) |
2804 | log.warning(TreeInfo.diagnosticPositionFor(svuid, tree), "constant.SVUID", c); |
2805 | } |
2806 | |
2807 | private Type capture(Type type) { |
2808 | return types.capture(type); |
2809 | } |
2810 | } |