1 /*
2 * Copyright (c) 1999, 2011, Oracle and/or its affiliates. All rights reserved.
3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
4 *
5 * This code is free software; you can redistribute it and/or modify it
6 * under the terms of the GNU General Public License version 2 only, as
7 * published by the Free Software Foundation. Oracle designates this
8 * particular file as subject to the "Classpath" exception as provided
9 * by Oracle in the LICENSE file that accompanied this code.
10 *
11 * This code is distributed in the hope that it will be useful, but WITHOUT
12 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
13 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
14 * version 2 for more details (a copy is included in the LICENSE file that
15 * accompanied this code).
16 *
17 * You should have received a copy of the GNU General Public License version
18 * 2 along with this work; if not, write to the Free Software Foundation,
19 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
20 *
21 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
22 * or visit www.oracle.com if you need additional information or have any
23 * questions.
24 */
25
26 package com.sun.tools.javac.comp;
27
28 import java.util.*;
29 import java.util.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.Lint.LintCategory;
42 import com.sun.tools.javac.code.Symbol.*;
43 import com.sun.tools.javac.tree.JCTree.*;
44 import com.sun.tools.javac.code.Type.*;
45
46 import com.sun.source.tree.IdentifierTree;
47 import com.sun.source.tree.MemberSelectTree;
48 import com.sun.source.tree.TreeVisitor;
49 import com.sun.source.util.SimpleTreeVisitor;
50
51 import static com.sun.tools.javac.code.Flags.*;
52 import static com.sun.tools.javac.code.Kinds.*;
53 import static com.sun.tools.javac.code.TypeTags.*;
54
55 /** This is the main context-dependent analysis phase in GJC. It
56 * encompasses name resolution, type checking and constant folding as
57 * subtasks. Some subtasks involve auxiliary classes.
58 * @see Check
59 * @see Resolve
60 * @see ConstFold
61 * @see Infer
62 *
63 * <p><b>This is NOT part of any supported API.
64 * If you write code that depends on this, you do so at your own risk.
65 * This code and its internal interfaces are subject to change or
66 * deletion without notice.</b>
67 */
68 public class Attr extends JCTree.Visitor {
69 protected static final Context.Key<Attr> attrKey =
70 new Context.Key<Attr>();
71
72 final Names names;
73 final Log log;
74 final Symtab syms;
75 final Resolve rs;
76 final Infer infer;
77 final Check chk;
78 final MemberEnter memberEnter;
79 final TreeMaker make;
80 final ConstFold cfolder;
81 final Enter enter;
82 final Target target;
83 final Types types;
84 final JCDiagnostic.Factory diags;
85 final Annotate annotate;
86 final DeferredLintHandler deferredLintHandler;
87
88 public static Attr instance(Context context) {
89 Attr instance = context.get(attrKey);
90 if (instance == null)
91 instance = new Attr(context);
92 return instance;
93 }
94
95 protected Attr(Context context) {
96 context.put(attrKey, this);
97
98 names = Names.instance(context);
99 log = Log.instance(context);
100 syms = Symtab.instance(context);
101 rs = Resolve.instance(context);
102 chk = Check.instance(context);
103 memberEnter = MemberEnter.instance(context);
104 make = TreeMaker.instance(context);
105 enter = Enter.instance(context);
106 infer = Infer.instance(context);
107 cfolder = ConstFold.instance(context);
108 target = Target.instance(context);
109 types = Types.instance(context);
110 diags = JCDiagnostic.Factory.instance(context);
111 annotate = Annotate.instance(context);
112 deferredLintHandler = DeferredLintHandler.instance(context);
113
114 Options options = Options.instance(context);
115
116 Source source = Source.instance(context);
117 allowGenerics = source.allowGenerics();
118 allowVarargs = source.allowVarargs();
119 allowEnums = source.allowEnums();
120 allowBoxing = source.allowBoxing();
121 allowCovariantReturns = source.allowCovariantReturns();
122 allowAnonOuterThis = source.allowAnonOuterThis();
123 allowStringsInSwitch = source.allowStringsInSwitch();
124 sourceName = source.name;
125 relax = (options.isSet("-retrofit") ||
126 options.isSet("-relax"));
127 findDiamonds = options.get("findDiamond") != null &&
128 source.allowDiamond();
129 useBeforeDeclarationWarning = options.isSet("useBeforeDeclarationWarning");
130 }
131
132 /** Switch: relax some constraints for retrofit mode.
133 */
134 boolean relax;
135
136 /** Switch: support generics?
137 */
138 boolean allowGenerics;
139
140 /** Switch: allow variable-arity methods.
141 */
142 boolean allowVarargs;
143
144 /** Switch: support enums?
145 */
146 boolean allowEnums;
147
148 /** Switch: support boxing and unboxing?
149 */
150 boolean allowBoxing;
151
152 /** Switch: support covariant result types?
153 */
154 boolean allowCovariantReturns;
155
156 /** Switch: allow references to surrounding object from anonymous
157 * objects during constructor call?
158 */
159 boolean allowAnonOuterThis;
160
161 /** Switch: generates a warning if diamond can be safely applied
162 * to a given new expression
163 */
164 boolean findDiamonds;
165
166 /**
167 * Internally enables/disables diamond finder feature
168 */
169 static final boolean allowDiamondFinder = true;
170
171 /**
172 * Switch: warn about use of variable before declaration?
173 * RFE: 6425594
174 */
175 boolean useBeforeDeclarationWarning;
176
177 /**
178 * Switch: allow strings in switch?
179 */
180 boolean allowStringsInSwitch;
181
182 /**
183 * Switch: name of source level; used for error reporting.
184 */
185 String sourceName;
186
187 /** Check kind and type of given tree against protokind and prototype.
188 * If check succeeds, store type in tree and return it.
189 * If check fails, store errType in tree and return it.
190 * No checks are performed if the prototype is a method type.
191 * It is not necessary in this case since we know that kind and type
192 * are correct.
193 *
194 * @param tree The tree whose kind and type is checked
195 * @param owntype The computed type of the tree
196 * @param ownkind The computed kind of the tree
197 * @param pkind The expected kind (or: protokind) of the tree
198 * @param pt The expected type (or: prototype) of the tree
199 */
200 Type check(JCTree tree, Type owntype, int ownkind, int pkind, Type pt) {
201 if (owntype.tag != ERROR && pt.tag != METHOD && pt.tag != FORALL) {
202 if ((ownkind & ~pkind) == 0) {
203 owntype = chk.checkType(tree.pos(), owntype, pt, errKey);
204 } else {
205 log.error(tree.pos(), "unexpected.type",
206 kindNames(pkind),
207 kindName(ownkind));
208 owntype = types.createErrorType(owntype);
209 }
210 }
211 tree.type = owntype;
212 return owntype;
213 }
214
215 /** Is given blank final variable assignable, i.e. in a scope where it
216 * may be assigned to even though it is final?
217 * @param v The blank final variable.
218 * @param env The current environment.
219 */
220 boolean isAssignableAsBlankFinal(VarSymbol v, Env<AttrContext> env) {
221 Symbol owner = env.info.scope.owner;
222 // owner refers to the innermost variable, method or
223 // initializer block declaration at this point.
224 return
225 v.owner == owner
226 ||
227 ((owner.name == names.init || // i.e. we are in a constructor
228 owner.kind == VAR || // i.e. we are in a variable initializer
229 (owner.flags() & BLOCK) != 0) // i.e. we are in an initializer block
230 &&
231 v.owner == owner.owner
232 &&
233 ((v.flags() & STATIC) != 0) == Resolve.isStatic(env));
234 }
235
236 /** Check that variable can be assigned to.
237 * @param pos The current source code position.
238 * @param v The assigned varaible
239 * @param base If the variable is referred to in a Select, the part
240 * to the left of the `.', null otherwise.
241 * @param env The current environment.
242 */
243 void checkAssignable(DiagnosticPosition pos, VarSymbol v, JCTree base, Env<AttrContext> env) {
244 if ((v.flags() & FINAL) != 0 &&
245 ((v.flags() & HASINIT) != 0
246 ||
247 !((base == null ||
248 (base.getTag() == JCTree.IDENT && TreeInfo.name(base) == names._this)) &&
249 isAssignableAsBlankFinal(v, env)))) {
250 if (v.isResourceVariable()) { //TWR resource
251 log.error(pos, "try.resource.may.not.be.assigned", v);
252 } else {
253 log.error(pos, "cant.assign.val.to.final.var", v);
254 }
255 } else if ((v.flags() & EFFECTIVELY_FINAL) != 0) {
256 v.flags_field &= ~EFFECTIVELY_FINAL;
257 }
258 }
259
260 /** Does tree represent a static reference to an identifier?
261 * It is assumed that tree is either a SELECT or an IDENT.
262 * We have to weed out selects from non-type names here.
263 * @param tree The candidate tree.
264 */
265 boolean isStaticReference(JCTree tree) {
266 if (tree.getTag() == JCTree.SELECT) {
267 Symbol lsym = TreeInfo.symbol(((JCFieldAccess) tree).selected);
268 if (lsym == null || lsym.kind != TYP) {
269 return false;
270 }
271 }
272 return true;
273 }
274
275 /** Is this symbol a type?
276 */
277 static boolean isType(Symbol sym) {
278 return sym != null && sym.kind == TYP;
279 }
280
281 /** The current `this' symbol.
282 * @param env The current environment.
283 */
284 Symbol thisSym(DiagnosticPosition pos, Env<AttrContext> env) {
285 return rs.resolveSelf(pos, env, env.enclClass.sym, names._this);
286 }
287
288 /** Attribute a parsed identifier.
289 * @param tree Parsed identifier name
290 * @param topLevel The toplevel to use
291 */
292 public Symbol attribIdent(JCTree tree, JCCompilationUnit topLevel) {
293 Env<AttrContext> localEnv = enter.topLevelEnv(topLevel);
294 localEnv.enclClass = make.ClassDef(make.Modifiers(0),
295 syms.errSymbol.name,
296 null, null, null, null);
297 localEnv.enclClass.sym = syms.errSymbol;
298 return tree.accept(identAttributer, localEnv);
299 }
300 // where
301 private TreeVisitor<Symbol,Env<AttrContext>> identAttributer = new IdentAttributer();
302 private class IdentAttributer extends SimpleTreeVisitor<Symbol,Env<AttrContext>> {
303 @Override
304 public Symbol visitMemberSelect(MemberSelectTree node, Env<AttrContext> env) {
305 Symbol site = visit(node.getExpression(), env);
306 if (site.kind == ERR)
307 return site;
308 Name name = (Name)node.getIdentifier();
309 if (site.kind == PCK) {
310 env.toplevel.packge = (PackageSymbol)site;
311 return rs.findIdentInPackage(env, (TypeSymbol)site, name, TYP | PCK);
312 } else {
313 env.enclClass.sym = (ClassSymbol)site;
314 return rs.findMemberType(env, site.asType(), name, (TypeSymbol)site);
315 }
316 }
317
318 @Override
319 public Symbol visitIdentifier(IdentifierTree node, Env<AttrContext> env) {
320 return rs.findIdent(env, (Name)node.getName(), TYP | PCK);
321 }
322 }
323
324 public Type coerce(Type etype, Type ttype) {
325 return cfolder.coerce(etype, ttype);
326 }
327
328 public Type attribType(JCTree node, TypeSymbol sym) {
329 Env<AttrContext> env = enter.typeEnvs.get(sym);
330 Env<AttrContext> localEnv = env.dup(node, env.info.dup());
331 return attribTree(node, localEnv, Kinds.TYP, Type.noType);
332 }
333
334 public Env<AttrContext> attribExprToTree(JCTree expr, Env<AttrContext> env, JCTree tree) {
335 breakTree = tree;
336 JavaFileObject prev = log.useSource(env.toplevel.sourcefile);
337 try {
338 attribExpr(expr, env);
339 } catch (BreakAttr b) {
340 return b.env;
341 } catch (AssertionError ae) {
342 if (ae.getCause() instanceof BreakAttr) {
343 return ((BreakAttr)(ae.getCause())).env;
344 } else {
345 throw ae;
346 }
347 } finally {
348 breakTree = null;
349 log.useSource(prev);
350 }
351 return env;
352 }
353
354 public Env<AttrContext> attribStatToTree(JCTree stmt, Env<AttrContext> env, JCTree tree) {
355 breakTree = tree;
356 JavaFileObject prev = log.useSource(env.toplevel.sourcefile);
357 try {
358 attribStat(stmt, env);
359 } catch (BreakAttr b) {
360 return b.env;
361 } catch (AssertionError ae) {
362 if (ae.getCause() instanceof BreakAttr) {
363 return ((BreakAttr)(ae.getCause())).env;
364 } else {
365 throw ae;
366 }
367 } finally {
368 breakTree = null;
369 log.useSource(prev);
370 }
371 return env;
372 }
373
374 private JCTree breakTree = null;
375
376 private static class BreakAttr extends RuntimeException {
377 static final long serialVersionUID = -6924771130405446405L;
378 private Env<AttrContext> env;
379 private BreakAttr(Env<AttrContext> env) {
380 this.env = env;
381 }
382 }
383
384
385 /* ************************************************************************
386 * Visitor methods
387 *************************************************************************/
388
389 /** Visitor argument: the current environment.
390 */
391 Env<AttrContext> env;
392
393 /** Visitor argument: the currently expected proto-kind.
394 */
395 int pkind;
396
397 /** Visitor argument: the currently expected proto-type.
398 */
399 Type pt;
400
401 /** Visitor argument: the error key to be generated when a type error occurs
402 */
403 String errKey;
404
405 /** Visitor result: the computed type.
406 */
407 Type result;
408
409 /** Visitor method: attribute a tree, catching any completion failure
410 * exceptions. Return the tree's type.
411 *
412 * @param tree The tree to be visited.
413 * @param env The environment visitor argument.
414 * @param pkind The protokind visitor argument.
415 * @param pt The prototype visitor argument.
416 */
417 Type attribTree(JCTree tree, Env<AttrContext> env, int pkind, Type pt) {
418 return attribTree(tree, env, pkind, pt, "incompatible.types");
419 }
420
421 Type attribTree(JCTree tree, Env<AttrContext> env, int pkind, Type pt, String errKey) {
422 Env<AttrContext> prevEnv = this.env;
423 int prevPkind = this.pkind;
424 Type prevPt = this.pt;
425 String prevErrKey = this.errKey;
426 try {
427 this.env = env;
428 this.pkind = pkind;
429 this.pt = pt;
430 this.errKey = errKey;
431 tree.accept(this);
432 if (tree == breakTree)
433 throw new BreakAttr(env);
434 return result;
435 } catch (CompletionFailure ex) {
436 tree.type = syms.errType;
437 return chk.completionError(tree.pos(), ex);
438 } finally {
439 this.env = prevEnv;
440 this.pkind = prevPkind;
441 this.pt = prevPt;
442 this.errKey = prevErrKey;
443 }
444 }
445
446 /** Derived visitor method: attribute an expression tree.
447 */
448 public Type attribExpr(JCTree tree, Env<AttrContext> env, Type pt) {
449 return attribTree(tree, env, VAL, pt.tag != ERROR ? pt : Type.noType);
450 }
451
452 public Type attribExpr(JCTree tree, Env<AttrContext> env, Type pt, String key) {
453 return attribTree(tree, env, VAL, pt.tag != ERROR ? pt : Type.noType, key);
454 }
455
456 /** Derived visitor method: attribute an expression tree with
457 * no constraints on the computed type.
458 */
459 Type attribExpr(JCTree tree, Env<AttrContext> env) {
460 return attribTree(tree, env, VAL, Type.noType);
461 }
462
463 /** Derived visitor method: attribute a type tree.
464 */
465 Type attribType(JCTree tree, Env<AttrContext> env) {
466 Type result = attribType(tree, env, Type.noType);
467 return result;
468 }
469
470 /** Derived visitor method: attribute a type tree.
471 */
472 Type attribType(JCTree tree, Env<AttrContext> env, Type pt) {
473 Type result = attribTree(tree, env, TYP, pt);
474 return result;
475 }
476
477 /** Derived visitor method: attribute a statement or definition tree.
478 */
479 public Type attribStat(JCTree tree, Env<AttrContext> env) {
480 return attribTree(tree, env, NIL, Type.noType);
481 }
482
483 /** Attribute a list of expressions, returning a list of types.
484 */
485 List<Type> attribExprs(List<JCExpression> trees, Env<AttrContext> env, Type pt) {
486 ListBuffer<Type> ts = new ListBuffer<Type>();
487 for (List<JCExpression> l = trees; l.nonEmpty(); l = l.tail)
488 ts.append(attribExpr(l.head, env, pt));
489 return ts.toList();
490 }
491
492 /** Attribute a list of statements, returning nothing.
493 */
494 <T extends JCTree> void attribStats(List<T> trees, Env<AttrContext> env) {
495 for (List<T> l = trees; l.nonEmpty(); l = l.tail)
496 attribStat(l.head, env);
497 }
498
499 /** Attribute the arguments in a method call, returning a list of types.
500 */
501 List<Type> attribArgs(List<JCExpression> trees, Env<AttrContext> env) {
502 ListBuffer<Type> argtypes = new ListBuffer<Type>();
503 for (List<JCExpression> l = trees; l.nonEmpty(); l = l.tail)
504 argtypes.append(chk.checkNonVoid(
505 l.head.pos(), types.upperBound(attribTree(l.head, env, VAL, Infer.anyPoly))));
506 return argtypes.toList();
507 }
508
509 /** Attribute a type argument list, returning a list of types.
510 * Caller is responsible for calling checkRefTypes.
511 */
512 List<Type> attribAnyTypes(List<JCExpression> trees, Env<AttrContext> env) {
513 ListBuffer<Type> argtypes = new ListBuffer<Type>();
514 for (List<JCExpression> l = trees; l.nonEmpty(); l = l.tail)
515 argtypes.append(attribType(l.head, env));
516 return argtypes.toList();
517 }
518
519 /** Attribute a type argument list, returning a list of types.
520 * Check that all the types are references.
521 */
522 List<Type> attribTypes(List<JCExpression> trees, Env<AttrContext> env) {
523 List<Type> types = attribAnyTypes(trees, env);
524 return chk.checkRefTypes(trees, types);
525 }
526
527 /**
528 * Attribute type variables (of generic classes or methods).
529 * Compound types are attributed later in attribBounds.
530 * @param typarams the type variables to enter
531 * @param env the current environment
532 */
533 void attribTypeVariables(List<JCTypeParameter> typarams, Env<AttrContext> env) {
534 for (JCTypeParameter tvar : typarams) {
535 TypeVar a = (TypeVar)tvar.type;
536 a.tsym.flags_field |= UNATTRIBUTED;
537 a.bound = Type.noType;
538 if (!tvar.bounds.isEmpty()) {
539 List<Type> bounds = List.of(attribType(tvar.bounds.head, env));
540 for (JCExpression bound : tvar.bounds.tail)
541 bounds = bounds.prepend(attribType(bound, env));
542 types.setBounds(a, bounds.reverse());
543 } else {
544 // if no bounds are given, assume a single bound of
545 // java.lang.Object.
546 types.setBounds(a, List.of(syms.objectType));
547 }
548 a.tsym.flags_field &= ~UNATTRIBUTED;
549 }
550 for (JCTypeParameter tvar : typarams)
551 chk.checkNonCyclic(tvar.pos(), (TypeVar)tvar.type);
552 attribStats(typarams, env);
553 }
554
555 void attribBounds(List<JCTypeParameter> typarams) {
556 for (JCTypeParameter typaram : typarams) {
557 Type bound = typaram.type.getUpperBound();
558 if (bound != null && bound.tsym instanceof ClassSymbol) {
559 ClassSymbol c = (ClassSymbol)bound.tsym;
560 if ((c.flags_field & COMPOUND) != 0) {
561 Assert.check((c.flags_field & UNATTRIBUTED) != 0, c);
562 attribClass(typaram.pos(), c);
563 }
564 }
565 }
566 }
567
568 /**
569 * Attribute the type references in a list of annotations.
570 */
571 void attribAnnotationTypes(List<JCAnnotation> annotations,
572 Env<AttrContext> env) {
573 for (List<JCAnnotation> al = annotations; al.nonEmpty(); al = al.tail) {
574 JCAnnotation a = al.head;
575 attribType(a.annotationType, env);
576 }
577 }
578
579 /**
580 * Attribute a "lazy constant value".
581 * @param env The env for the const value
582 * @param initializer The initializer for the const value
583 * @param type The expected type, or null
584 * @see VarSymbol#setlazyConstValue
585 */
586 public Object attribLazyConstantValue(Env<AttrContext> env,
587 JCTree.JCExpression initializer,
588 Type type) {
589
590 // in case no lint value has been set up for this env, scan up
591 // env stack looking for smallest enclosing env for which it is set.
592 Env<AttrContext> lintEnv = env;
593 while (lintEnv.info.lint == null)
594 lintEnv = lintEnv.next;
595
596 // Having found the enclosing lint value, we can initialize the lint value for this class
597 env.info.lint = lintEnv.info.lint.augment(env.info.enclVar.attributes_field, env.info.enclVar.flags());
598
599 Lint prevLint = chk.setLint(env.info.lint);
600 JavaFileObject prevSource = log.useSource(env.toplevel.sourcefile);
601
602 try {
603 Type itype = attribExpr(initializer, env, type);
604 if (itype.constValue() != null)
605 return coerce(itype, type).constValue();
606 else
607 return null;
608 } finally {
609 env.info.lint = prevLint;
610 log.useSource(prevSource);
611 }
612 }
613
614 /** Attribute type reference in an `extends' or `implements' clause.
615 * Supertypes of anonymous inner classes are usually already attributed.
616 *
617 * @param tree The tree making up the type reference.
618 * @param env The environment current at the reference.
619 * @param classExpected true if only a class is expected here.
620 * @param interfaceExpected true if only an interface is expected here.
621 */
622 Type attribBase(JCTree tree,
623 Env<AttrContext> env,
624 boolean classExpected,
625 boolean interfaceExpected,
626 boolean checkExtensible) {
627 Type t = tree.type != null ?
628 tree.type :
629 attribType(tree, env);
630 return checkBase(t, tree, env, classExpected, interfaceExpected, checkExtensible);
631 }
632 Type checkBase(Type t,
633 JCTree tree,
634 Env<AttrContext> env,
635 boolean classExpected,
636 boolean interfaceExpected,
637 boolean checkExtensible) {
638 if (t.isErroneous())
639 return t;
640 if (t.tag == TYPEVAR && !classExpected && !interfaceExpected) {
641 // check that type variable is already visible
642 if (t.getUpperBound() == null) {
643 log.error(tree.pos(), "illegal.forward.ref");
644 return types.createErrorType(t);
645 }
646 } else {
647 t = chk.checkClassType(tree.pos(), t, checkExtensible|!allowGenerics);
648 }
649 if (interfaceExpected && (t.tsym.flags() & INTERFACE) == 0) {
650 log.error(tree.pos(), "intf.expected.here");
651 // return errType is necessary since otherwise there might
652 // be undetected cycles which cause attribution to loop
653 return types.createErrorType(t);
654 } else if (checkExtensible &&
655 classExpected &&
656 (t.tsym.flags() & INTERFACE) != 0) {
657 log.error(tree.pos(), "no.intf.expected.here");
658 return types.createErrorType(t);
659 }
660 if (checkExtensible &&
661 ((t.tsym.flags() & FINAL) != 0)) {
662 log.error(tree.pos(),
663 "cant.inherit.from.final", t.tsym);
664 }
665 chk.checkNonCyclic(tree.pos(), t);
666 return t;
667 }
668
669 public void visitClassDef(JCClassDecl tree) {
670 // Local classes have not been entered yet, so we need to do it now:
671 if ((env.info.scope.owner.kind & (VAR | MTH)) != 0)
672 enter.classEnter(tree, env);
673
674 ClassSymbol c = tree.sym;
675 if (c == null) {
676 // exit in case something drastic went wrong during enter.
677 result = null;
678 } else {
679 // make sure class has been completed:
680 c.complete();
681
682 // If this class appears as an anonymous class
683 // in a superclass constructor call where
684 // no explicit outer instance is given,
685 // disable implicit outer instance from being passed.
686 // (This would be an illegal access to "this before super").
687 if (env.info.isSelfCall &&
688 env.tree.getTag() == JCTree.NEWCLASS &&
689 ((JCNewClass) env.tree).encl == null)
690 {
691 c.flags_field |= NOOUTERTHIS;
692 }
693 attribClass(tree.pos(), c);
694 result = tree.type = c.type;
695 }
696 }
697
698 public void visitMethodDef(JCMethodDecl tree) {
699 MethodSymbol m = tree.sym;
700
701 Lint lint = env.info.lint.augment(m.attributes_field, m.flags());
702 Lint prevLint = chk.setLint(lint);
703 MethodSymbol prevMethod = chk.setMethod(m);
704 try {
705 deferredLintHandler.flush(tree.pos());
706 chk.checkDeprecatedAnnotation(tree.pos(), m);
707
708 attribBounds(tree.typarams);
709
710 // If we override any other methods, check that we do so properly.
711 // JLS ???
712 if (m.isStatic()) {
713 chk.checkHideClashes(tree.pos(), env.enclClass.type, m);
714 } else {
715 chk.checkOverrideClashes(tree.pos(), env.enclClass.type, m);
716 }
717 chk.checkOverride(tree, m);
718
719 // Create a new environment with local scope
720 // for attributing the method.
721 Env<AttrContext> localEnv = memberEnter.methodEnv(tree, env);
722
723 localEnv.info.lint = lint;
724
725 // Enter all type parameters into the local method scope.
726 for (List<JCTypeParameter> l = tree.typarams; l.nonEmpty(); l = l.tail)
727 localEnv.info.scope.enterIfAbsent(l.head.type.tsym);
728
729 ClassSymbol owner = env.enclClass.sym;
730 if ((owner.flags() & ANNOTATION) != 0 &&
731 tree.params.nonEmpty())
732 log.error(tree.params.head.pos(),
733 "intf.annotation.members.cant.have.params");
734
735 // Attribute all value parameters.
736 for (List<JCVariableDecl> l = tree.params; l.nonEmpty(); l = l.tail) {
737 attribStat(l.head, localEnv);
738 }
739
740 chk.checkVarargsMethodDecl(localEnv, tree);
741
742 // Check that type parameters are well-formed.
743 chk.validate(tree.typarams, localEnv);
744
745 // Check that result type is well-formed.
746 chk.validate(tree.restype, localEnv);
747
748 // annotation method checks
749 if ((owner.flags() & ANNOTATION) != 0) {
750 // annotation method cannot have throws clause
751 if (tree.thrown.nonEmpty()) {
752 log.error(tree.thrown.head.pos(),
753 "throws.not.allowed.in.intf.annotation");
754 }
755 // annotation method cannot declare type-parameters
756 if (tree.typarams.nonEmpty()) {
757 log.error(tree.typarams.head.pos(),
758 "intf.annotation.members.cant.have.type.params");
759 }
760 // validate annotation method's return type (could be an annotation type)
761 chk.validateAnnotationType(tree.restype);
762 // ensure that annotation method does not clash with members of Object/Annotation
763 chk.validateAnnotationMethod(tree.pos(), m);
764
765 if (tree.defaultValue != null) {
766 // if default value is an annotation, check it is a well-formed
767 // annotation value (e.g. no duplicate values, no missing values, etc.)
768 chk.validateAnnotationTree(tree.defaultValue);
769 }
770 }
771
772 for (List<JCExpression> l = tree.thrown; l.nonEmpty(); l = l.tail)
773 chk.checkType(l.head.pos(), l.head.type, syms.throwableType);
774
775 if (tree.body == null) {
776 // Empty bodies are only allowed for
777 // abstract, native, or interface methods, or for methods
778 // in a retrofit signature class.
779 if ((owner.flags() & INTERFACE) == 0 &&
780 (tree.mods.flags & (ABSTRACT | NATIVE)) == 0 &&
781 !relax)
782 log.error(tree.pos(), "missing.meth.body.or.decl.abstract");
783 if (tree.defaultValue != null) {
784 if ((owner.flags() & ANNOTATION) == 0)
785 log.error(tree.pos(),
786 "default.allowed.in.intf.annotation.member");
787 }
788 } else if ((owner.flags() & INTERFACE) != 0) {
789 log.error(tree.body.pos(), "intf.meth.cant.have.body");
790 } else if ((tree.mods.flags & ABSTRACT) != 0) {
791 log.error(tree.pos(), "abstract.meth.cant.have.body");
792 } else if ((tree.mods.flags & NATIVE) != 0) {
793 log.error(tree.pos(), "native.meth.cant.have.body");
794 } else {
795 // Add an implicit super() call unless an explicit call to
796 // super(...) or this(...) is given
797 // or we are compiling class java.lang.Object.
798 if (tree.name == names.init && owner.type != syms.objectType) {
799 JCBlock body = tree.body;
800 if (body.stats.isEmpty() ||
801 !TreeInfo.isSelfCall(body.stats.head)) {
802 body.stats = body.stats.
803 prepend(memberEnter.SuperCall(make.at(body.pos),
804 List.<Type>nil(),
805 List.<JCVariableDecl>nil(),
806 false));
807 } else if ((env.enclClass.sym.flags() & ENUM) != 0 &&
808 (tree.mods.flags & GENERATEDCONSTR) == 0 &&
809 TreeInfo.isSuperCall(body.stats.head)) {
810 // enum constructors are not allowed to call super
811 // directly, so make sure there aren't any super calls
812 // in enum constructors, except in the compiler
813 // generated one.
814 log.error(tree.body.stats.head.pos(),
815 "call.to.super.not.allowed.in.enum.ctor",
816 env.enclClass.sym);
817 }
818 }
819
820 // Attribute method body.
821 attribStat(tree.body, localEnv);
822 }
823 localEnv.info.scope.leave();
824 result = tree.type = m.type;
825 chk.validateAnnotations(tree.mods.annotations, m);
826 }
827 finally {
828 chk.setLint(prevLint);
829 chk.setMethod(prevMethod);
830 }
831 }
832
833 public void visitVarDef(JCVariableDecl tree) {
834 // Local variables have not been entered yet, so we need to do it now:
835 if (env.info.scope.owner.kind == MTH) {
836 if (tree.sym != null) {
837 // parameters have already been entered
838 env.info.scope.enter(tree.sym);
839 } else {
840 memberEnter.memberEnter(tree, env);
841 annotate.flush();
842 }
843 tree.sym.flags_field |= EFFECTIVELY_FINAL;
844 }
845
846 VarSymbol v = tree.sym;
847 Lint lint = env.info.lint.augment(v.attributes_field, v.flags());
848 Lint prevLint = chk.setLint(lint);
849
850 // Check that the variable's declared type is well-formed.
851 chk.validate(tree.vartype, env);
852 deferredLintHandler.flush(tree.pos());
853
854 try {
855 chk.checkDeprecatedAnnotation(tree.pos(), v);
856
857 if (tree.init != null) {
858 if ((v.flags_field & FINAL) != 0 && tree.init.getTag() != JCTree.NEWCLASS) {
859 // In this case, `v' is final. Ensure that it's initializer is
860 // evaluated.
861 v.getConstValue(); // ensure initializer is evaluated
862 } else {
863 // Attribute initializer in a new environment
864 // with the declared variable as owner.
865 // Check that initializer conforms to variable's declared type.
866 Env<AttrContext> initEnv = memberEnter.initEnv(tree, env);
867 initEnv.info.lint = lint;
868 // In order to catch self-references, we set the variable's
869 // declaration position to maximal possible value, effectively
870 // marking the variable as undefined.
871 initEnv.info.enclVar = v;
872 attribExpr(tree.init, initEnv, v.type);
873 }
874 }
875 result = tree.type = v.type;
876 chk.validateAnnotations(tree.mods.annotations, v);
877 }
878 finally {
879 chk.setLint(prevLint);
880 }
881 }
882
883 public void visitSkip(JCSkip tree) {
884 result = null;
885 }
886
887 public void visitBlock(JCBlock tree) {
888 if (env.info.scope.owner.kind == TYP) {
889 // Block is a static or instance initializer;
890 // let the owner of the environment be a freshly
891 // created BLOCK-method.
892 Env<AttrContext> localEnv =
893 env.dup(tree, env.info.dup(env.info.scope.dupUnshared()));
894 localEnv.info.scope.owner =
895 new MethodSymbol(tree.flags | BLOCK, names.empty, null,
896 env.info.scope.owner);
897 if ((tree.flags & STATIC) != 0) localEnv.info.staticLevel++;
898 attribStats(tree.stats, localEnv);
899 } else {
900 // Create a new local environment with a local scope.
901 Env<AttrContext> localEnv =
902 env.dup(tree, env.info.dup(env.info.scope.dup()));
903 attribStats(tree.stats, localEnv);
904 localEnv.info.scope.leave();
905 }
906 result = null;
907 }
908
909 public void visitDoLoop(JCDoWhileLoop tree) {
910 attribStat(tree.body, env.dup(tree));
911 attribExpr(tree.cond, env, syms.booleanType);
912 result = null;
913 }
914
915 public void visitWhileLoop(JCWhileLoop tree) {
916 attribExpr(tree.cond, env, syms.booleanType);
917 attribStat(tree.body, env.dup(tree));
918 result = null;
919 }
920
921 public void visitForLoop(JCForLoop tree) {
922 Env<AttrContext> loopEnv =
923 env.dup(env.tree, env.info.dup(env.info.scope.dup()));
924 attribStats(tree.init, loopEnv);
925 if (tree.cond != null) attribExpr(tree.cond, loopEnv, syms.booleanType);
926 loopEnv.tree = tree; // before, we were not in loop!
927 attribStats(tree.step, loopEnv);
928 attribStat(tree.body, loopEnv);
929 loopEnv.info.scope.leave();
930 result = null;
931 }
932
933 public void visitForeachLoop(JCEnhancedForLoop tree) {
934 Env<AttrContext> loopEnv =
935 env.dup(env.tree, env.info.dup(env.info.scope.dup()));
936 attribStat(tree.var, loopEnv);
937 Type exprType = types.upperBound(attribExpr(tree.expr, loopEnv));
938 chk.checkNonVoid(tree.pos(), exprType);
939 Type elemtype = types.elemtype(exprType); // perhaps expr is an array?
940 if (elemtype == null) {
941 // or perhaps expr implements Iterable<T>?
942 Type base = types.asSuper(exprType, syms.iterableType.tsym);
943 if (base == null) {
944 log.error(tree.expr.pos(),
945 "foreach.not.applicable.to.type",
946 exprType,
947 diags.fragment("type.req.array.or.iterable"));
948 elemtype = types.createErrorType(exprType);
949 } else {
950 List<Type> iterableParams = base.allparams();
951 elemtype = iterableParams.isEmpty()
952 ? syms.objectType
953 : types.upperBound(iterableParams.head);
954 }
955 }
956 chk.checkType(tree.expr.pos(), elemtype, tree.var.sym.type);
957 loopEnv.tree = tree; // before, we were not in loop!
958 attribStat(tree.body, loopEnv);
959 loopEnv.info.scope.leave();
960 result = null;
961 }
962
963 public void visitLabelled(JCLabeledStatement tree) {
964 // Check that label is not used in an enclosing statement
965 Env<AttrContext> env1 = env;
966 while (env1 != null && env1.tree.getTag() != JCTree.CLASSDEF) {
967 if (env1.tree.getTag() == JCTree.LABELLED &&
968 ((JCLabeledStatement) env1.tree).label == tree.label) {
969 log.error(tree.pos(), "label.already.in.use",
970 tree.label);
971 break;
972 }
973 env1 = env1.next;
974 }
975
976 attribStat(tree.body, env.dup(tree));
977 result = null;
978 }
979
980 public void visitSwitch(JCSwitch tree) {
981 Type seltype = attribExpr(tree.selector, env);
982
983 Env<AttrContext> switchEnv =
984 env.dup(tree, env.info.dup(env.info.scope.dup()));
985
986 boolean enumSwitch =
987 allowEnums &&
988 (seltype.tsym.flags() & Flags.ENUM) != 0;
989 boolean stringSwitch = false;
990 if (types.isSameType(seltype, syms.stringType)) {
991 if (allowStringsInSwitch) {
992 stringSwitch = true;
993 } else {
994 log.error(tree.selector.pos(), "string.switch.not.supported.in.source", sourceName);
995 }
996 }
997 if (!enumSwitch && !stringSwitch)
998 seltype = chk.checkType(tree.selector.pos(), seltype, syms.intType);
999
1000 // Attribute all cases and
1001 // check that there are no duplicate case labels or default clauses.
1002 Set<Object> labels = new HashSet<Object>(); // The set of case labels.
1003 boolean hasDefault = false; // Is there a default label?
1004 for (List<JCCase> l = tree.cases; l.nonEmpty(); l = l.tail) {
1005 JCCase c = l.head;
1006 Env<AttrContext> caseEnv =
1007 switchEnv.dup(c, env.info.dup(switchEnv.info.scope.dup()));
1008 if (c.pat != null) {
1009 if (enumSwitch) {
1010 Symbol sym = enumConstant(c.pat, seltype);
1011 if (sym == null) {
1012 log.error(c.pat.pos(), "enum.label.must.be.unqualified.enum");
1013 } else if (!labels.add(sym)) {
1014 log.error(c.pos(), "duplicate.case.label");
1015 }
1016 } else {
1017 Type pattype = attribExpr(c.pat, switchEnv, seltype);
1018 if (pattype.tag != ERROR) {
1019 if (pattype.constValue() == null) {
1020 log.error(c.pat.pos(),
1021 (stringSwitch ? "string.const.req" : "const.expr.req"));
1022 } else if (labels.contains(pattype.constValue())) {
1023 log.error(c.pos(), "duplicate.case.label");
1024 } else {
1025 labels.add(pattype.constValue());
1026 }
1027 }
1028 }
1029 } else if (hasDefault) {
1030 log.error(c.pos(), "duplicate.default.label");
1031 } else {
1032 hasDefault = true;
1033 }
1034 attribStats(c.stats, caseEnv);
1035 caseEnv.info.scope.leave();
1036 addVars(c.stats, switchEnv.info.scope);
1037 }
1038
1039 switchEnv.info.scope.leave();
1040 result = null;
1041 }
1042 // where
1043 /** Add any variables defined in stats to the switch scope. */
1044 private static void addVars(List<JCStatement> stats, Scope switchScope) {
1045 for (;stats.nonEmpty(); stats = stats.tail) {
1046 JCTree stat = stats.head;
1047 if (stat.getTag() == JCTree.VARDEF)
1048 switchScope.enter(((JCVariableDecl) stat).sym);
1049 }
1050 }
1051 // where
1052 /** Return the selected enumeration constant symbol, or null. */
1053 private Symbol enumConstant(JCTree tree, Type enumType) {
1054 if (tree.getTag() != JCTree.IDENT) {
1055 log.error(tree.pos(), "enum.label.must.be.unqualified.enum");
1056 return syms.errSymbol;
1057 }
1058 JCIdent ident = (JCIdent)tree;
1059 Name name = ident.name;
1060 for (Scope.Entry e = enumType.tsym.members().lookup(name);
1061 e.scope != null; e = e.next()) {
1062 if (e.sym.kind == VAR) {
1063 Symbol s = ident.sym = e.sym;
1064 ((VarSymbol)s).getConstValue(); // ensure initializer is evaluated
1065 ident.type = s.type;
1066 return ((s.flags_field & Flags.ENUM) == 0)
1067 ? null : s;
1068 }
1069 }
1070 return null;
1071 }
1072
1073 public void visitSynchronized(JCSynchronized tree) {
1074 chk.checkRefType(tree.pos(), attribExpr(tree.lock, env));
1075 attribStat(tree.body, env);
1076 result = null;
1077 }
1078
1079 public void visitTry(JCTry tree) {
1080 // Create a new local environment with a local
1081 Env<AttrContext> localEnv = env.dup(tree, env.info.dup(env.info.scope.dup()));
1082 boolean isTryWithResource = tree.resources.nonEmpty();
1083 // Create a nested environment for attributing the try block if needed
1084 Env<AttrContext> tryEnv = isTryWithResource ?
1085 env.dup(tree, localEnv.info.dup(localEnv.info.scope.dup())) :
1086 localEnv;
1087 // Attribute resource declarations
1088 for (JCTree resource : tree.resources) {
1089 if (resource.getTag() == JCTree.VARDEF) {
1090 attribStat(resource, tryEnv);
1091 chk.checkType(resource, resource.type, syms.autoCloseableType, "try.not.applicable.to.type");
1092
1093 //check that resource type cannot throw InterruptedException
1094 checkAutoCloseable(resource.pos(), localEnv, resource.type);
1095
1096 VarSymbol var = (VarSymbol)TreeInfo.symbolFor(resource);
1097 var.setData(ElementKind.RESOURCE_VARIABLE);
1098 } else {
1099 attribExpr(resource, tryEnv, syms.autoCloseableType, "try.not.applicable.to.type");
1100 }
1101 }
1102 // Attribute body
1103 attribStat(tree.body, tryEnv);
1104 if (isTryWithResource)
1105 tryEnv.info.scope.leave();
1106
1107 // Attribute catch clauses
1108 for (List<JCCatch> l = tree.catchers; l.nonEmpty(); l = l.tail) {
1109 JCCatch c = l.head;
1110 Env<AttrContext> catchEnv =
1111 localEnv.dup(c, localEnv.info.dup(localEnv.info.scope.dup()));
1112 Type ctype = attribStat(c.param, catchEnv);
1113 if (TreeInfo.isMultiCatch(c)) {
1114 //multi-catch parameter is implicitly marked as final
1115 c.param.sym.flags_field |= FINAL | DISJUNCTION;
1116 }
1117 if (c.param.sym.kind == Kinds.VAR) {
1118 c.param.sym.setData(ElementKind.EXCEPTION_PARAMETER);
1119 }
1120 chk.checkType(c.param.vartype.pos(),
1121 chk.checkClassType(c.param.vartype.pos(), ctype),
1122 syms.throwableType);
1123 attribStat(c.body, catchEnv);
1124 catchEnv.info.scope.leave();
1125 }
1126
1127 // Attribute finalizer
1128 if (tree.finalizer != null) attribStat(tree.finalizer, localEnv);
1129
1130 localEnv.info.scope.leave();
1131 result = null;
1132 }
1133
1134 void checkAutoCloseable(DiagnosticPosition pos, Env<AttrContext> env, Type resource) {
1135 if (!resource.isErroneous() &&
1136 types.asSuper(resource, syms.autoCloseableType.tsym) != null) {
1137 Symbol close = syms.noSymbol;
1138 boolean prevDeferDiags = log.deferDiagnostics;
1139 Queue<JCDiagnostic> prevDeferredDiags = log.deferredDiagnostics;
1140 try {
1141 log.deferDiagnostics = true;
1142 log.deferredDiagnostics = ListBuffer.lb();
1143 close = rs.resolveQualifiedMethod(pos,
1144 env,
1145 resource,
1146 names.close,
1147 List.<Type>nil(),
1148 List.<Type>nil());
1149 }
1150 finally {
1151 log.deferDiagnostics = prevDeferDiags;
1152 log.deferredDiagnostics = prevDeferredDiags;
1153 }
1154 if (close.kind == MTH &&
1155 close.overrides(syms.autoCloseableClose, resource.tsym, types, true) &&
1156 chk.isHandled(syms.interruptedExceptionType, types.memberType(resource, close).getThrownTypes()) &&
1157 env.info.lint.isEnabled(LintCategory.TRY)) {
1158 log.warning(LintCategory.TRY, pos, "try.resource.throws.interrupted.exc", resource);
1159 }
1160 }
1161 }
1162
1163 public void visitConditional(JCConditional tree) {
1164 attribExpr(tree.cond, env, syms.booleanType);
1165 attribExpr(tree.truepart, env);
1166 attribExpr(tree.falsepart, env);
1167 result = check(tree,
1168 capture(condType(tree.pos(), tree.cond.type,
1169 tree.truepart.type, tree.falsepart.type)),
1170 VAL, pkind, pt);
1171 }
1172 //where
1173 /** Compute the type of a conditional expression, after
1174 * checking that it exists. See Spec 15.25.
1175 *
1176 * @param pos The source position to be used for
1177 * error diagnostics.
1178 * @param condtype The type of the expression's condition.
1179 * @param thentype The type of the expression's then-part.
1180 * @param elsetype The type of the expression's else-part.
1181 */
1182 private Type condType(DiagnosticPosition pos,
1183 Type condtype,
1184 Type thentype,
1185 Type elsetype) {
1186 Type ctype = condType1(pos, condtype, thentype, elsetype);
1187
1188 // If condition and both arms are numeric constants,
1189 // evaluate at compile-time.
1190 return ((condtype.constValue() != null) &&
1191 (thentype.constValue() != null) &&
1192 (elsetype.constValue() != null))
1193 ? cfolder.coerce(condtype.isTrue()?thentype:elsetype, ctype)
1194 : ctype;
1195 }
1196 /** Compute the type of a conditional expression, after
1197 * checking that it exists. Does not take into
1198 * account the special case where condition and both arms
1199 * are constants.
1200 *
1201 * @param pos The source position to be used for error
1202 * diagnostics.
1203 * @param condtype The type of the expression's condition.
1204 * @param thentype The type of the expression's then-part.
1205 * @param elsetype The type of the expression's else-part.
1206 */
1207 private Type condType1(DiagnosticPosition pos, Type condtype,
1208 Type thentype, Type elsetype) {
1209 // If same type, that is the result
1210 if (types.isSameType(thentype, elsetype))
1211 return thentype.baseType();
1212
1213 Type thenUnboxed = (!allowBoxing || thentype.isPrimitive())
1214 ? thentype : types.unboxedType(thentype);
1215 Type elseUnboxed = (!allowBoxing || elsetype.isPrimitive())
1216 ? elsetype : types.unboxedType(elsetype);
1217
1218 // Otherwise, if both arms can be converted to a numeric
1219 // type, return the least numeric type that fits both arms
1220 // (i.e. return larger of the two, or return int if one
1221 // arm is short, the other is char).
1222 if (thenUnboxed.isPrimitive() && elseUnboxed.isPrimitive()) {
1223 // If one arm has an integer subrange type (i.e., byte,
1224 // short, or char), and the other is an integer constant
1225 // that fits into the subrange, return the subrange type.
1226 if (thenUnboxed.tag < INT && elseUnboxed.tag == INT &&
1227 types.isAssignable(elseUnboxed, thenUnboxed))
1228 return thenUnboxed.baseType();
1229 if (elseUnboxed.tag < INT && thenUnboxed.tag == INT &&
1230 types.isAssignable(thenUnboxed, elseUnboxed))
1231 return elseUnboxed.baseType();
1232
1233 for (int i = BYTE; i < VOID; i++) {
1234 Type candidate = syms.typeOfTag[i];
1235 if (types.isSubtype(thenUnboxed, candidate) &&
1236 types.isSubtype(elseUnboxed, candidate))
1237 return candidate;
1238 }
1239 }
1240
1241 // Those were all the cases that could result in a primitive
1242 if (allowBoxing) {
1243 if (thentype.isPrimitive())
1244 thentype = types.boxedClass(thentype).type;
1245 if (elsetype.isPrimitive())
1246 elsetype = types.boxedClass(elsetype).type;
1247 }
1248
1249 if (types.isSubtype(thentype, elsetype))
1250 return elsetype.baseType();
1251 if (types.isSubtype(elsetype, thentype))
1252 return thentype.baseType();
1253
1254 if (!allowBoxing || thentype.tag == VOID || elsetype.tag == VOID) {
1255 log.error(pos, "neither.conditional.subtype",
1256 thentype, elsetype);
1257 return thentype.baseType();
1258 }
1259
1260 // both are known to be reference types. The result is
1261 // lub(thentype,elsetype). This cannot fail, as it will
1262 // always be possible to infer "Object" if nothing better.
1263 return types.lub(thentype.baseType(), elsetype.baseType());
1264 }
1265
1266 public void visitIf(JCIf tree) {
1267 attribExpr(tree.cond, env, syms.booleanType);
1268 attribStat(tree.thenpart, env);
1269 if (tree.elsepart != null)
1270 attribStat(tree.elsepart, env);
1271 chk.checkEmptyIf(tree);
1272 result = null;
1273 }
1274
1275 public void visitExec(JCExpressionStatement tree) {
1276 //a fresh environment is required for 292 inference to work properly ---
1277 //see Infer.instantiatePolymorphicSignatureInstance()
1278 Env<AttrContext> localEnv = env.dup(tree);
1279 attribExpr(tree.expr, localEnv);
1280 result = null;
1281 }
1282
1283 public void visitBreak(JCBreak tree) {
1284 tree.target = findJumpTarget(tree.pos(), tree.getTag(), tree.label, env);
1285 result = null;
1286 }
1287
1288 public void visitContinue(JCContinue tree) {
1289 tree.target = findJumpTarget(tree.pos(), tree.getTag(), tree.label, env);
1290 result = null;
1291 }
1292 //where
1293 /** Return the target of a break or continue statement, if it exists,
1294 * report an error if not.
1295 * Note: The target of a labelled break or continue is the
1296 * (non-labelled) statement tree referred to by the label,
1297 * not the tree representing the labelled statement itself.
1298 *
1299 * @param pos The position to be used for error diagnostics
1300 * @param tag The tag of the jump statement. This is either
1301 * Tree.BREAK or Tree.CONTINUE.
1302 * @param label The label of the jump statement, or null if no
1303 * label is given.
1304 * @param env The environment current at the jump statement.
1305 */
1306 private JCTree findJumpTarget(DiagnosticPosition pos,
1307 int tag,
1308 Name label,
1309 Env<AttrContext> env) {
1310 // Search environments outwards from the point of jump.
1311 Env<AttrContext> env1 = env;
1312 LOOP:
1313 while (env1 != null) {
1314 switch (env1.tree.getTag()) {
1315 case JCTree.LABELLED:
1316 JCLabeledStatement labelled = (JCLabeledStatement)env1.tree;
1317 if (label == labelled.label) {
1318 // If jump is a continue, check that target is a loop.
1319 if (tag == JCTree.CONTINUE) {
1320 if (labelled.body.getTag() != JCTree.DOLOOP &&
1321 labelled.body.getTag() != JCTree.WHILELOOP &&
1322 labelled.body.getTag() != JCTree.FORLOOP &&
1323 labelled.body.getTag() != JCTree.FOREACHLOOP)
1324 log.error(pos, "not.loop.label", label);
1325 // Found labelled statement target, now go inwards
1326 // to next non-labelled tree.
1327 return TreeInfo.referencedStatement(labelled);
1328 } else {
1329 return labelled;
1330 }
1331 }
1332 break;
1333 case JCTree.DOLOOP:
1334 case JCTree.WHILELOOP:
1335 case JCTree.FORLOOP:
1336 case JCTree.FOREACHLOOP:
1337 if (label == null) return env1.tree;
1338 break;
1339 case JCTree.SWITCH:
1340 if (label == null && tag == JCTree.BREAK) return env1.tree;
1341 break;
1342 case JCTree.METHODDEF:
1343 case JCTree.CLASSDEF:
1344 break LOOP;
1345 default:
1346 }
1347 env1 = env1.next;
1348 }
1349 if (label != null)
1350 log.error(pos, "undef.label", label);
1351 else if (tag == JCTree.CONTINUE)
1352 log.error(pos, "cont.outside.loop");
1353 else
1354 log.error(pos, "break.outside.switch.loop");
1355 return null;
1356 }
1357
1358 public void visitReturn(JCReturn tree) {
1359 // Check that there is an enclosing method which is
1360 // nested within than the enclosing class.
1361 if (env.enclMethod == null ||
1362 env.enclMethod.sym.owner != env.enclClass.sym) {
1363 log.error(tree.pos(), "ret.outside.meth");
1364
1365 } else {
1366 // Attribute return expression, if it exists, and check that
1367 // it conforms to result type of enclosing method.
1368 Symbol m = env.enclMethod.sym;
1369 if (m.type.getReturnType().tag == VOID) {
1370 if (tree.expr != null)
1371 log.error(tree.expr.pos(),
1372 "cant.ret.val.from.meth.decl.void");
1373 } else if (tree.expr == null) {
1374 log.error(tree.pos(), "missing.ret.val");
1375 } else {
1376 attribExpr(tree.expr, env, m.type.getReturnType());
1377 }
1378 }
1379 result = null;
1380 }
1381
1382 public void visitThrow(JCThrow tree) {
1383 attribExpr(tree.expr, env, syms.throwableType);
1384 result = null;
1385 }
1386
1387 public void visitAssert(JCAssert tree) {
1388 attribExpr(tree.cond, env, syms.booleanType);
1389 if (tree.detail != null) {
1390 chk.checkNonVoid(tree.detail.pos(), attribExpr(tree.detail, env));
1391 }
1392 result = null;
1393 }
1394
1395 /** Visitor method for method invocations.
1396 * NOTE: The method part of an application will have in its type field
1397 * the return type of the method, not the method's type itself!
1398 */
1399 public void visitApply(JCMethodInvocation tree) {
1400 // The local environment of a method application is
1401 // a new environment nested in the current one.
1402 Env<AttrContext> localEnv = env.dup(tree, env.info.dup());
1403
1404 // The types of the actual method arguments.
1405 List<Type> argtypes;
1406
1407 // The types of the actual method type arguments.
1408 List<Type> typeargtypes = null;
1409
1410 Name methName = TreeInfo.name(tree.meth);
1411
1412 boolean isConstructorCall =
1413 methName == names._this || methName == names._super;
1414
1415 if (isConstructorCall) {
1416 // We are seeing a ...this(...) or ...super(...) call.
1417 // Check that this is the first statement in a constructor.
1418 if (checkFirstConstructorStat(tree, env)) {
1419
1420 // Record the fact
1421 // that this is a constructor call (using isSelfCall).
1422 localEnv.info.isSelfCall = true;
1423
1424 // Attribute arguments, yielding list of argument types.
1425 argtypes = attribArgs(tree.args, localEnv);
1426 typeargtypes = attribTypes(tree.typeargs, localEnv);
1427
1428 // Variable `site' points to the class in which the called
1429 // constructor is defined.
1430 Type site = env.enclClass.sym.type;
1431 if (methName == names._super) {
1432 if (site == syms.objectType) {
1433 log.error(tree.meth.pos(), "no.superclass", site);
1434 site = types.createErrorType(syms.objectType);
1435 } else {
1436 site = types.supertype(site);
1437 }
1438 }
1439
1440 if (site.tag == CLASS) {
1441 Type encl = site.getEnclosingType();
1442 while (encl != null && encl.tag == TYPEVAR)
1443 encl = encl.getUpperBound();
1444 if (encl.tag == CLASS) {
1445 // we are calling a nested class
1446
1447 if (tree.meth.getTag() == JCTree.SELECT) {
1448 JCTree qualifier = ((JCFieldAccess) tree.meth).selected;
1449
1450 // We are seeing a prefixed call, of the form
1451 // <expr>.super(...).
1452 // Check that the prefix expression conforms
1453 // to the outer instance type of the class.
1454 chk.checkRefType(qualifier.pos(),
1455 attribExpr(qualifier, localEnv,
1456 encl));
1457 } else if (methName == names._super) {
1458 // qualifier omitted; check for existence
1459 // of an appropriate implicit qualifier.
1460 rs.resolveImplicitThis(tree.meth.pos(),
1461 localEnv, site, true);
1462 }
1463 } else if (tree.meth.getTag() == JCTree.SELECT) {
1464 log.error(tree.meth.pos(), "illegal.qual.not.icls",
1465 site.tsym);
1466 }
1467
1468 // if we're calling a java.lang.Enum constructor,
1469 // prefix the implicit String and int parameters
1470 if (site.tsym == syms.enumSym && allowEnums)
1471 argtypes = argtypes.prepend(syms.intType).prepend(syms.stringType);
1472
1473 // Resolve the called constructor under the assumption
1474 // that we are referring to a superclass instance of the
1475 // current instance (JLS ???).
1476 boolean selectSuperPrev = localEnv.info.selectSuper;
1477 localEnv.info.selectSuper = true;
1478 localEnv.info.varArgs = false;
1479 Symbol sym = rs.resolveConstructor(
1480 tree.meth.pos(), localEnv, site, argtypes, typeargtypes);
1481 localEnv.info.selectSuper = selectSuperPrev;
1482
1483 // Set method symbol to resolved constructor...
1484 TreeInfo.setSymbol(tree.meth, sym);
1485
1486 // ...and check that it is legal in the current context.
1487 // (this will also set the tree's type)
1488 Type mpt = newMethTemplate(argtypes, typeargtypes);
1489 checkId(tree.meth, site, sym, localEnv, MTH,
1490 mpt, tree.varargsElement != null);
1491 }
1492 // Otherwise, `site' is an error type and we do nothing
1493 }
1494 result = tree.type = syms.voidType;
1495 } else {
1496 // Otherwise, we are seeing a regular method call.
1497 // Attribute the arguments, yielding list of argument types, ...
1498 argtypes = attribArgs(tree.args, localEnv);
1499 typeargtypes = attribAnyTypes(tree.typeargs, localEnv);
1500
1501 // ... and attribute the method using as a prototype a methodtype
1502 // whose formal argument types is exactly the list of actual
1503 // arguments (this will also set the method symbol).
1504 Type mpt = newMethTemplate(argtypes, typeargtypes);
1505 localEnv.info.varArgs = false;
1506 Type mtype = attribExpr(tree.meth, localEnv, mpt);
1507 if (localEnv.info.varArgs)
1508 Assert.check(mtype.isErroneous() || tree.varargsElement != null);
1509
1510 // Compute the result type.
1511 Type restype = mtype.getReturnType();
1512 if (restype.tag == WILDCARD)
1513 throw new AssertionError(mtype);
1514
1515 // as a special case, array.clone() has a result that is
1516 // the same as static type of the array being cloned
1517 if (tree.meth.getTag() == JCTree.SELECT &&
1518 allowCovariantReturns &&
1519 methName == names.clone &&
1520 types.isArray(((JCFieldAccess) tree.meth).selected.type))
1521 restype = ((JCFieldAccess) tree.meth).selected.type;
1522
1523 // as a special case, x.getClass() has type Class<? extends |X|>
1524 if (allowGenerics &&
1525 methName == names.getClass && tree.args.isEmpty()) {
1526 Type qualifier = (tree.meth.getTag() == JCTree.SELECT)
1527 ? ((JCFieldAccess) tree.meth).selected.type
1528 : env.enclClass.sym.type;
1529 restype = new
1530 ClassType(restype.getEnclosingType(),
1531 List.<Type>of(new WildcardType(types.erasure(qualifier),
1532 BoundKind.EXTENDS,
1533 syms.boundClass)),
1534 restype.tsym);
1535 }
1536
1537 chk.checkRefTypes(tree.typeargs, typeargtypes);
1538
1539 // Check that value of resulting type is admissible in the
1540 // current context. Also, capture the return type
1541 result = check(tree, capture(restype), VAL, pkind, pt);
1542 }
1543 chk.validate(tree.typeargs, localEnv);
1544 }
1545 //where
1546 /** Check that given application node appears as first statement
1547 * in a constructor call.
1548 * @param tree The application node
1549 * @param env The environment current at the application.
1550 */
1551 boolean checkFirstConstructorStat(JCMethodInvocation tree, Env<AttrContext> env) {
1552 JCMethodDecl enclMethod = env.enclMethod;
1553 if (enclMethod != null && enclMethod.name == names.init) {
1554 JCBlock body = enclMethod.body;
1555 if (body.stats.head.getTag() == JCTree.EXEC &&
1556 ((JCExpressionStatement) body.stats.head).expr == tree)
1557 return true;
1558 }
1559 log.error(tree.pos(),"call.must.be.first.stmt.in.ctor",
1560 TreeInfo.name(tree.meth));
1561 return false;
1562 }
1563
1564 /** Obtain a method type with given argument types.
1565 */
1566 Type newMethTemplate(List<Type> argtypes, List<Type> typeargtypes) {
1567 MethodType mt = new MethodType(argtypes, null, null, syms.methodClass);
1568 return (typeargtypes == null) ? mt : (Type)new ForAll(typeargtypes, mt);
1569 }
1570
1571 public void visitNewClass(JCNewClass tree) {
1572 Type owntype = types.createErrorType(tree.type);
1573
1574 // The local environment of a class creation is
1575 // a new environment nested in the current one.
1576 Env<AttrContext> localEnv = env.dup(tree, env.info.dup());
1577
1578 // The anonymous inner class definition of the new expression,
1579 // if one is defined by it.
1580 JCClassDecl cdef = tree.def;
1581
1582 // If enclosing class is given, attribute it, and
1583 // complete class name to be fully qualified
1584 JCExpression clazz = tree.clazz; // Class field following new
1585 JCExpression clazzid = // Identifier in class field
1586 (clazz.getTag() == JCTree.TYPEAPPLY)
1587 ? ((JCTypeApply) clazz).clazz
1588 : clazz;
1589
1590 JCExpression clazzid1 = clazzid; // The same in fully qualified form
1591
1592 if (tree.encl != null) {
1593 // We are seeing a qualified new, of the form
1594 // <expr>.new C <...> (...) ...
1595 // In this case, we let clazz stand for the name of the
1596 // allocated class C prefixed with the type of the qualifier
1597 // expression, so that we can
1598 // resolve it with standard techniques later. I.e., if
1599 // <expr> has type T, then <expr>.new C <...> (...)
1600 // yields a clazz T.C.
1601 Type encltype = chk.checkRefType(tree.encl.pos(),
1602 attribExpr(tree.encl, env));
1603 clazzid1 = make.at(clazz.pos).Select(make.Type(encltype),
1604 ((JCIdent) clazzid).name);
1605 if (clazz.getTag() == JCTree.TYPEAPPLY)
1606 clazz = make.at(tree.pos).
1607 TypeApply(clazzid1,
1608 ((JCTypeApply) clazz).arguments);
1609 else
1610 clazz = clazzid1;
1611 }
1612
1613 // Attribute clazz expression and store
1614 // symbol + type back into the attributed tree.
1615 Type clazztype = attribType(clazz, env);
1616 Pair<Scope,Scope> mapping = getSyntheticScopeMapping(clazztype);
1617 clazztype = chk.checkDiamond(tree, clazztype);
1618 chk.validate(clazz, localEnv);
1619 if (tree.encl != null) {
1620 // We have to work in this case to store
1621 // symbol + type back into the attributed tree.
1622 tree.clazz.type = clazztype;
1623 TreeInfo.setSymbol(clazzid, TreeInfo.symbol(clazzid1));
1624 clazzid.type = ((JCIdent) clazzid).sym.type;
1625 if (!clazztype.isErroneous()) {
1626 if (cdef != null && clazztype.tsym.isInterface()) {
1627 log.error(tree.encl.pos(), "anon.class.impl.intf.no.qual.for.new");
1628 } else if (clazztype.tsym.isStatic()) {
1629 log.error(tree.encl.pos(), "qualified.new.of.static.class", clazztype.tsym);
1630 }
1631 }
1632 } else if (!clazztype.tsym.isInterface() &&
1633 clazztype.getEnclosingType().tag == CLASS) {
1634 // Check for the existence of an apropos outer instance
1635 rs.resolveImplicitThis(tree.pos(), env, clazztype);
1636 }
1637
1638 // Attribute constructor arguments.
1639 List<Type> argtypes = attribArgs(tree.args, localEnv);
1640 List<Type> typeargtypes = attribTypes(tree.typeargs, localEnv);
1641
1642 if (TreeInfo.isDiamond(tree) && !clazztype.isErroneous()) {
1643 clazztype = attribDiamond(localEnv, tree, clazztype, mapping, argtypes, typeargtypes);
1644 clazz.type = clazztype;
1645 } else if (allowDiamondFinder &&
1646 tree.def == null &&
1647 !clazztype.isErroneous() &&
1648 clazztype.getTypeArguments().nonEmpty() &&
1649 findDiamonds) {
1650 boolean prevDeferDiags = log.deferDiagnostics;
1651 Queue<JCDiagnostic> prevDeferredDiags = log.deferredDiagnostics;
1652 Type inferred = null;
1653 try {
1654 //disable diamond-related diagnostics
1655 log.deferDiagnostics = true;
1656 log.deferredDiagnostics = ListBuffer.lb();
1657 inferred = attribDiamond(localEnv,
1658 tree,
1659 clazztype,
1660 mapping,
1661 argtypes,
1662 typeargtypes);
1663 }
1664 finally {
1665 log.deferDiagnostics = prevDeferDiags;
1666 log.deferredDiagnostics = prevDeferredDiags;
1667 }
1668 if (inferred != null &&
1669 !inferred.isErroneous() &&
1670 inferred.tag == CLASS &&
1671 types.isAssignable(inferred, pt.tag == NONE ? clazztype : pt, Warner.noWarnings)) {
1672 String key = types.isSameType(clazztype, inferred) ?
1673 "diamond.redundant.args" :
1674 "diamond.redundant.args.1";
1675 log.warning(tree.clazz.pos(), key, clazztype, inferred);
1676 }
1677 }
1678
1679 // If we have made no mistakes in the class type...
1680 if (clazztype.tag == CLASS) {
1681 // Enums may not be instantiated except implicitly
1682 if (allowEnums &&
1683 (clazztype.tsym.flags_field&Flags.ENUM) != 0 &&
1684 (env.tree.getTag() != JCTree.VARDEF ||
1685 (((JCVariableDecl) env.tree).mods.flags&Flags.ENUM) == 0 ||
1686 ((JCVariableDecl) env.tree).init != tree))
1687 log.error(tree.pos(), "enum.cant.be.instantiated");
1688 // Check that class is not abstract
1689 if (cdef == null &&
1690 (clazztype.tsym.flags() & (ABSTRACT | INTERFACE)) != 0) {
1691 log.error(tree.pos(), "abstract.cant.be.instantiated",
1692 clazztype.tsym);
1693 } else if (cdef != null && clazztype.tsym.isInterface()) {
1694 // Check that no constructor arguments are given to
1695 // anonymous classes implementing an interface
1696 if (!argtypes.isEmpty())
1697 log.error(tree.args.head.pos(), "anon.class.impl.intf.no.args");
1698
1699 if (!typeargtypes.isEmpty())
1700 log.error(tree.typeargs.head.pos(), "anon.class.impl.intf.no.typeargs");
1701
1702 // Error recovery: pretend no arguments were supplied.
1703 argtypes = List.nil();
1704 typeargtypes = List.nil();
1705 }
1706
1707 // Resolve the called constructor under the assumption
1708 // that we are referring to a superclass instance of the
1709 // current instance (JLS ???).
1710 else {
1711 localEnv.info.selectSuper = cdef != null;
1712 localEnv.info.varArgs = false;
1713 tree.constructor = rs.resolveConstructor(
1714 tree.pos(), localEnv, clazztype, argtypes, typeargtypes);
1715 tree.constructorType = tree.constructor.type.isErroneous() ?
1716 syms.errType :
1717 checkMethod(clazztype,
1718 tree.constructor,
1719 localEnv,
1720 tree.args,
1721 argtypes,
1722 typeargtypes,
1723 localEnv.info.varArgs);
1724 if (localEnv.info.varArgs)
1725 Assert.check(tree.constructorType.isErroneous() || tree.varargsElement != null);
1726 }
1727
1728 if (cdef != null) {
1729 // We are seeing an anonymous class instance creation.
1730 // In this case, the class instance creation
1731 // expression
1732 //
1733 // E.new <typeargs1>C<typargs2>(args) { ... }
1734 //
1735 // is represented internally as
1736 //
1737 // E . new <typeargs1>C<typargs2>(args) ( class <empty-name> { ... } ) .
1738 //
1739 // This expression is then *transformed* as follows:
1740 //
1741 // (1) add a STATIC flag to the class definition
1742 // if the current environment is static
1743 // (2) add an extends or implements clause
1744 // (3) add a constructor.
1745 //
1746 // For instance, if C is a class, and ET is the type of E,
1747 // the expression
1748 //
1749 // E.new <typeargs1>C<typargs2>(args) { ... }
1750 //
1751 // is translated to (where X is a fresh name and typarams is the
1752 // parameter list of the super constructor):
1753 //
1754 // new <typeargs1>X(<*nullchk*>E, args) where
1755 // X extends C<typargs2> {
1756 // <typarams> X(ET e, args) {
1757 // e.<typeargs1>super(args)
1758 // }
1759 // ...
1760 // }
1761 if (Resolve.isStatic(env)) cdef.mods.flags |= STATIC;
1762
1763 if (clazztype.tsym.isInterface()) {
1764 cdef.implementing = List.of(clazz);
1765 } else {
1766 cdef.extending = clazz;
1767 }
1768
1769 attribStat(cdef, localEnv);
1770
1771 // If an outer instance is given,
1772 // prefix it to the constructor arguments
1773 // and delete it from the new expression
1774 if (tree.encl != null && !clazztype.tsym.isInterface()) {
1775 tree.args = tree.args.prepend(makeNullCheck(tree.encl));
1776 argtypes = argtypes.prepend(tree.encl.type);
1777 tree.encl = null;
1778 }
1779
1780 // Reassign clazztype and recompute constructor.
1781 clazztype = cdef.sym.type;
1782 Symbol sym = rs.resolveConstructor(
1783 tree.pos(), localEnv, clazztype, argtypes,
1784 typeargtypes, true, tree.varargsElement != null);
1785 Assert.check(sym.kind < AMBIGUOUS || tree.constructor.type.isErroneous());
1786 tree.constructor = sym;
1787 if (tree.constructor.kind > ERRONEOUS) {
1788 tree.constructorType = syms.errType;
1789 }
1790 else {
1791 tree.constructorType = checkMethod(clazztype,
1792 tree.constructor,
1793 localEnv,
1794 tree.args,
1795 argtypes,
1796 typeargtypes,
1797 localEnv.info.varArgs);
1798 }
1799 }
1800
1801 if (tree.constructor != null && tree.constructor.kind == MTH)
1802 owntype = clazztype;
1803 }
1804 result = check(tree, owntype, VAL, pkind, pt);
1805 chk.validate(tree.typeargs, localEnv);
1806 }
1807
1808 Type attribDiamond(Env<AttrContext> env,
1809 JCNewClass tree,
1810 Type clazztype,
1811 Pair<Scope, Scope> mapping,
1812 List<Type> argtypes,
1813 List<Type> typeargtypes) {
1814 if (clazztype.isErroneous() ||
1815 clazztype.isInterface() ||
1816 mapping == erroneousMapping) {
1817 //if the type of the instance creation expression is erroneous,
1818 //or if it's an interface, or if something prevented us to form a valid
1819 //mapping, return the (possibly erroneous) type unchanged
1820 return clazztype;
1821 }
1822
1823 //dup attribution environment and augment the set of inference variables
1824 Env<AttrContext> localEnv = env.dup(tree);
1825 localEnv.info.tvars = clazztype.tsym.type.getTypeArguments();
1826
1827 //if the type of the instance creation expression is a class type
1828 //apply method resolution inference (JLS 15.12.2.7). The return type
1829 //of the resolved constructor will be a partially instantiated type
1830 ((ClassSymbol) clazztype.tsym).members_field = mapping.snd;
1831 Symbol constructor;
1832 try {
1833 constructor = rs.resolveDiamond(tree.pos(),
1834 localEnv,
1835 clazztype.tsym.type,
1836 argtypes,
1837 typeargtypes);
1838 } finally {
1839 ((ClassSymbol) clazztype.tsym).members_field = mapping.fst;
1840 }
1841 if (constructor.kind == MTH) {
1842 ClassType ct = new ClassType(clazztype.getEnclosingType(),
1843 clazztype.tsym.type.getTypeArguments(),
1844 clazztype.tsym);
1845 clazztype = checkMethod(ct,
1846 constructor,
1847 localEnv,
1848 tree.args,
1849 argtypes,
1850 typeargtypes,
1851 localEnv.info.varArgs).getReturnType();
1852 } else {
1853 clazztype = syms.errType;
1854 }
1855
1856 if (clazztype.tag == FORALL && !pt.isErroneous()) {
1857 //if the resolved constructor's return type has some uninferred
1858 //type-variables, infer them using the expected type and declared
1859 //bounds (JLS 15.12.2.8).
1860 try {
1861 clazztype = infer.instantiateExpr((ForAll) clazztype,
1862 pt.tag == NONE ? syms.objectType : pt,
1863 Warner.noWarnings);
1864 } catch (Infer.InferenceException ex) {
1865 //an error occurred while inferring uninstantiated type-variables
1866 log.error(tree.clazz.pos(),
1867 "cant.apply.diamond.1",
1868 diags.fragment("diamond", clazztype.tsym),
1869 ex.diagnostic);
1870 }
1871 }
1872 return chk.checkClassType(tree.clazz.pos(),
1873 clazztype,
1874 true);
1875 }
1876
1877 /** Creates a synthetic scope containing fake generic constructors.
1878 * Assuming that the original scope contains a constructor of the kind:
1879 * Foo(X x, Y y), where X,Y are class type-variables declared in Foo,
1880 * the synthetic scope is added a generic constructor of the kind:
1881 * <X,Y>Foo<X,Y>(X x, Y y). This is crucial in order to enable diamond
1882 * inference. The inferred return type of the synthetic constructor IS
1883 * the inferred type for the diamond operator.
1884 */
1885 private Pair<Scope, Scope> getSyntheticScopeMapping(Type ctype) {
1886 if (ctype.tag != CLASS) {
1887 return erroneousMapping;
1888 }
1889
1890 Pair<Scope, Scope> mapping =
1891 new Pair<Scope, Scope>(ctype.tsym.members(), new Scope(ctype.tsym));
1892
1893 //for each constructor in the original scope, create a synthetic constructor
1894 //whose return type is the type of the class in which the constructor is
1895 //declared, and insert it into the new scope.
1896 for (Scope.Entry e = mapping.fst.lookup(names.init);
1897 e.scope != null;
1898 e = e.next()) {
1899 Type synthRestype = new ClassType(ctype.getEnclosingType(),
1900 ctype.tsym.type.getTypeArguments(),
1901 ctype.tsym);
1902 MethodSymbol synhConstr = new MethodSymbol(e.sym.flags(),
1903 names.init,
1904 types.createMethodTypeWithReturn(e.sym.type, synthRestype),
1905 e.sym.owner);
1906 mapping.snd.enter(synhConstr);
1907 }
1908 return mapping;
1909 }
1910
1911 private final Pair<Scope,Scope> erroneousMapping = new Pair<Scope,Scope>(null, null);
1912
1913 /** Make an attributed null check tree.
1914 */
1915 public JCExpression makeNullCheck(JCExpression arg) {
1916 // optimization: X.this is never null; skip null check
1917 Name name = TreeInfo.name(arg);
1918 if (name == names._this || name == names._super) return arg;
1919
1920 int optag = JCTree.NULLCHK;
1921 JCUnary tree = make.at(arg.pos).Unary(optag, arg);
1922 tree.operator = syms.nullcheck;
1923 tree.type = arg.type;
1924 return tree;
1925 }
1926
1927 public void visitNewArray(JCNewArray tree) {
1928 Type owntype = types.createErrorType(tree.type);
1929 Type elemtype;
1930 if (tree.elemtype != null) {
1931 elemtype = attribType(tree.elemtype, env);
1932 chk.validate(tree.elemtype, env);
1933 owntype = elemtype;
1934 for (List<JCExpression> l = tree.dims; l.nonEmpty(); l = l.tail) {
1935 attribExpr(l.head, env, syms.intType);
1936 owntype = new ArrayType(owntype, syms.arrayClass);
1937 }
1938 } else {
1939 // we are seeing an untyped aggregate { ... }
1940 // this is allowed only if the prototype is an array
1941 if (pt.tag == ARRAY) {
1942 elemtype = types.elemtype(pt);
1943 } else {
1944 if (pt.tag != ERROR) {
1945 log.error(tree.pos(), "illegal.initializer.for.type",
1946 pt);
1947 }
1948 elemtype = types.createErrorType(pt);
1949 }
1950 }
1951 if (tree.elems != null) {
1952 attribExprs(tree.elems, env, elemtype);
1953 owntype = new ArrayType(elemtype, syms.arrayClass);
1954 }
1955 if (!types.isReifiable(elemtype))
1956 log.error(tree.pos(), "generic.array.creation");
1957 result = check(tree, owntype, VAL, pkind, pt);
1958 }
1959
1960 public void visitParens(JCParens tree) {
1961 Type owntype = attribTree(tree.expr, env, pkind, pt);
1962 result = check(tree, owntype, pkind, pkind, pt);
1963 Symbol sym = TreeInfo.symbol(tree);
1964 if (sym != null && (sym.kind&(TYP|PCK)) != 0)
1965 log.error(tree.pos(), "illegal.start.of.type");
1966 }
1967
1968 public void visitAssign(JCAssign tree) {
1969 Type owntype = attribTree(tree.lhs, env.dup(tree), VAR, Type.noType);
1970 Type capturedType = capture(owntype);
1971 attribExpr(tree.rhs, env, owntype);
1972 result = check(tree, capturedType, VAL, pkind, pt);
1973 }
1974
1975 public void visitAssignop(JCAssignOp tree) {
1976 // Attribute arguments.
1977 Type owntype = attribTree(tree.lhs, env, VAR, Type.noType);
1978 Type operand = attribExpr(tree.rhs, env);
1979 // Find operator.
1980 Symbol operator = tree.operator = rs.resolveBinaryOperator(
1981 tree.pos(), tree.getTag() - JCTree.ASGOffset, env,
1982 owntype, operand);
1983
1984 if (operator.kind == MTH &&
1985 !owntype.isErroneous() &&
1986 !operand.isErroneous()) {
1987 chk.checkOperator(tree.pos(),
1988 (OperatorSymbol)operator,
1989 tree.getTag() - JCTree.ASGOffset,
1990 owntype,
1991 operand);
1992 chk.checkDivZero(tree.rhs.pos(), operator, operand);
1993 chk.checkCastable(tree.rhs.pos(),
1994 operator.type.getReturnType(),
1995 owntype);
1996 }
1997 result = check(tree, owntype, VAL, pkind, pt);
1998 }
1999
2000 public void visitUnary(JCUnary tree) {
2001 // Attribute arguments.
2002 Type argtype = (JCTree.PREINC <= tree.getTag() && tree.getTag() <= JCTree.POSTDEC)
2003 ? attribTree(tree.arg, env, VAR, Type.noType)
2004 : chk.checkNonVoid(tree.arg.pos(), attribExpr(tree.arg, env));
2005
2006 // Find operator.
2007 Symbol operator = tree.operator =
2008 rs.resolveUnaryOperator(tree.pos(), tree.getTag(), env, argtype);
2009
2010 Type owntype = types.createErrorType(tree.type);
2011 if (operator.kind == MTH &&
2012 !argtype.isErroneous()) {
2013 owntype = (JCTree.PREINC <= tree.getTag() && tree.getTag() <= JCTree.POSTDEC)
2014 ? tree.arg.type
2015 : operator.type.getReturnType();
2016 int opc = ((OperatorSymbol)operator).opcode;
2017
2018 // If the argument is constant, fold it.
2019 if (argtype.constValue() != null) {
2020 Type ctype = cfolder.fold1(opc, argtype);
2021 if (ctype != null) {
2022 owntype = cfolder.coerce(ctype, owntype);
2023
2024 // Remove constant types from arguments to
2025 // conserve space. The parser will fold concatenations
2026 // of string literals; the code here also
2027 // gets rid of intermediate results when some of the
2028 // operands are constant identifiers.
2029 if (tree.arg.type.tsym == syms.stringType.tsym) {
2030 tree.arg.type = syms.stringType;
2031 }
2032 }
2033 }
2034 }
2035 result = check(tree, owntype, VAL, pkind, pt);
2036 }
2037
2038 public void visitBinary(JCBinary tree) {
2039 // Attribute arguments.
2040 Type left = chk.checkNonVoid(tree.lhs.pos(), attribExpr(tree.lhs, env));
2041 Type right = chk.checkNonVoid(tree.lhs.pos(), attribExpr(tree.rhs, env));
2042
2043 // Find operator.
2044 Symbol operator = tree.operator =
2045 rs.resolveBinaryOperator(tree.pos(), tree.getTag(), env, left, right);
2046
2047 Type owntype = types.createErrorType(tree.type);
2048 if (operator.kind == MTH &&
2049 !left.isErroneous() &&
2050 !right.isErroneous()) {
2051 owntype = operator.type.getReturnType();
2052 int opc = chk.checkOperator(tree.lhs.pos(),
2053 (OperatorSymbol)operator,
2054 tree.getTag(),
2055 left,
2056 right);
2057
2058 // If both arguments are constants, fold them.
2059 if (left.constValue() != null && right.constValue() != null) {
2060 Type ctype = cfolder.fold2(opc, left, right);
2061 if (ctype != null) {
2062 owntype = cfolder.coerce(ctype, owntype);
2063
2064 // Remove constant types from arguments to
2065 // conserve space. The parser will fold concatenations
2066 // of string literals; the code here also
2067 // gets rid of intermediate results when some of the
2068 // operands are constant identifiers.
2069 if (tree.lhs.type.tsym == syms.stringType.tsym) {
2070 tree.lhs.type = syms.stringType;
2071 }
2072 if (tree.rhs.type.tsym == syms.stringType.tsym) {
2073 tree.rhs.type = syms.stringType;
2074 }
2075 }
2076 }
2077
2078 // Check that argument types of a reference ==, != are
2079 // castable to each other, (JLS???).
2080 if ((opc == ByteCodes.if_acmpeq || opc == ByteCodes.if_acmpne)) {
2081 if (!types.isCastable(left, right, new Warner(tree.pos()))) {
2082 log.error(tree.pos(), "incomparable.types", left, right);
2083 }
2084 }
2085
2086 chk.checkDivZero(tree.rhs.pos(), operator, right);
2087 }
2088 result = check(tree, owntype, VAL, pkind, pt);
2089 }
2090
2091 public void visitTypeCast(JCTypeCast tree) {
2092 Type clazztype = attribType(tree.clazz, env);
2093 chk.validate(tree.clazz, env, false);
2094 //a fresh environment is required for 292 inference to work properly ---
2095 //see Infer.instantiatePolymorphicSignatureInstance()
2096 Env<AttrContext> localEnv = env.dup(tree);
2097 Type exprtype = attribExpr(tree.expr, localEnv, Infer.anyPoly);
2098 Type owntype = chk.checkCastable(tree.expr.pos(), exprtype, clazztype);
2099 if (exprtype.constValue() != null)
2100 owntype = cfolder.coerce(exprtype, owntype);
2101 result = check(tree, capture(owntype), VAL, pkind, pt);
2102 }
2103
2104 public void visitTypeTest(JCInstanceOf tree) {
2105 Type exprtype = chk.checkNullOrRefType(
2106 tree.expr.pos(), attribExpr(tree.expr, env));
2107 Type clazztype = chk.checkReifiableReferenceType(
2108 tree.clazz.pos(), attribType(tree.clazz, env));
2109 chk.validate(tree.clazz, env, false);
2110 chk.checkCastable(tree.expr.pos(), exprtype, clazztype);
2111 result = check(tree, syms.booleanType, VAL, pkind, pt);
2112 }
2113
2114 public void visitIndexed(JCArrayAccess tree) {
2115 Type owntype = types.createErrorType(tree.type);
2116 Type atype = attribExpr(tree.indexed, env);
2117 attribExpr(tree.index, env, syms.intType);
2118 if (types.isArray(atype))
2119 owntype = types.elemtype(atype);
2120 else if (atype.tag != ERROR)
2121 log.error(tree.pos(), "array.req.but.found", atype);
2122 if ((pkind & VAR) == 0) owntype = capture(owntype);
2123 result = check(tree, owntype, VAR, pkind, pt);
2124 }
2125
2126 public void visitIdent(JCIdent tree) {
2127 Symbol sym;
2128 boolean varArgs = false;
2129
2130 // Find symbol
2131 if (pt.tag == METHOD || pt.tag == FORALL) {
2132 // If we are looking for a method, the prototype `pt' will be a
2133 // method type with the type of the call's arguments as parameters.
2134 env.info.varArgs = false;
2135 sym = rs.resolveMethod(tree.pos(), env, tree.name, pt.getParameterTypes(), pt.getTypeArguments());
2136 varArgs = env.info.varArgs;
2137 } else if (tree.sym != null && tree.sym.kind != VAR) {
2138 sym = tree.sym;
2139 } else {
2140 sym = rs.resolveIdent(tree.pos(), env, tree.name, pkind);
2141 }
2142 tree.sym = sym;
2143
2144 // (1) Also find the environment current for the class where
2145 // sym is defined (`symEnv').
2146 // Only for pre-tiger versions (1.4 and earlier):
2147 // (2) Also determine whether we access symbol out of an anonymous
2148 // class in a this or super call. This is illegal for instance
2149 // members since such classes don't carry a this$n link.
2150 // (`noOuterThisPath').
2151 Env<AttrContext> symEnv = env;
2152 boolean noOuterThisPath = false;
2153 if (env.enclClass.sym.owner.kind != PCK && // we are in an inner class
2154 (sym.kind & (VAR | MTH | TYP)) != 0 &&
2155 sym.owner.kind == TYP &&
2156 tree.name != names._this && tree.name != names._super) {
2157
2158 // Find environment in which identifier is defined.
2159 while (symEnv.outer != null &&
2160 !sym.isMemberOf(symEnv.enclClass.sym, types)) {
2161 if ((symEnv.enclClass.sym.flags() & NOOUTERTHIS) != 0)
2162 noOuterThisPath = !allowAnonOuterThis;
2163 symEnv = symEnv.outer;
2164 }
2165 }
2166
2167 // If symbol is a variable, ...
2168 if (sym.kind == VAR) {
2169 VarSymbol v = (VarSymbol)sym;
2170
2171 // ..., evaluate its initializer, if it has one, and check for
2172 // illegal forward reference.
2173 checkInit(tree, env, v, false);
2174
2175 // If symbol is a local variable accessed from an embedded
2176 // inner class check that it is final.
2177 if (v.owner.kind == MTH &&
2178 v.owner != env.info.scope.owner &&
2179 (v.flags_field & FINAL) == 0) {
2180 log.error(tree.pos(),
2181 "local.var.accessed.from.icls.needs.final",
2182 v);
2183 }
2184
2185 // If we are expecting a variable (as opposed to a value), check
2186 // that the variable is assignable in the current environment.
2187 if (pkind == VAR)
2188 checkAssignable(tree.pos(), v, null, env);
2189 }
2190
2191 // In a constructor body,
2192 // if symbol is a field or instance method, check that it is
2193 // not accessed before the supertype constructor is called.
2194 if ((symEnv.info.isSelfCall || noOuterThisPath) &&
2195 (sym.kind & (VAR | MTH)) != 0 &&
2196 sym.owner.kind == TYP &&
2197 (sym.flags() & STATIC) == 0) {
2198 chk.earlyRefError(tree.pos(), sym.kind == VAR ? sym : thisSym(tree.pos(), env));
2199 }
2200 Env<AttrContext> env1 = env;
2201 if (sym.kind != ERR && sym.kind != TYP && sym.owner != null && sym.owner != env1.enclClass.sym) {
2202 // If the found symbol is inaccessible, then it is
2203 // accessed through an enclosing instance. Locate this
2204 // enclosing instance:
2205 while (env1.outer != null && !rs.isAccessible(env, env1.enclClass.sym.type, sym))
2206 env1 = env1.outer;
2207 }
2208 result = checkId(tree, env1.enclClass.sym.type, sym, env, pkind, pt, varArgs);
2209 }
2210
2211 public void visitSelect(JCFieldAccess tree) {
2212 // Determine the expected kind of the qualifier expression.
2213 int skind = 0;
2214 if (tree.name == names._this || tree.name == names._super ||
2215 tree.name == names._class)
2216 {
2217 skind = TYP;
2218 } else {
2219 if ((pkind & PCK) != 0) skind = skind | PCK;
2220 if ((pkind & TYP) != 0) skind = skind | TYP | PCK;
2221 if ((pkind & (VAL | MTH)) != 0) skind = skind | VAL | TYP;
2222 }
2223
2224 // Attribute the qualifier expression, and determine its symbol (if any).
2225 Type site = attribTree(tree.selected, env, skind, Infer.anyPoly);
2226 if ((pkind & (PCK | TYP)) == 0)
2227 site = capture(site); // Capture field access
2228
2229 // don't allow T.class T[].class, etc
2230 if (skind == TYP) {
2231 Type elt = site;
2232 while (elt.tag == ARRAY)
2233 elt = ((ArrayType)elt).elemtype;
2234 if (elt.tag == TYPEVAR) {
2235 log.error(tree.pos(), "type.var.cant.be.deref");
2236 result = types.createErrorType(tree.type);
2237 return;
2238 }
2239 }
2240
2241 // If qualifier symbol is a type or `super', assert `selectSuper'
2242 // for the selection. This is relevant for determining whether
2243 // protected symbols are accessible.
2244 Symbol sitesym = TreeInfo.symbol(tree.selected);
2245 boolean selectSuperPrev = env.info.selectSuper;
2246 env.info.selectSuper =
2247 sitesym != null &&
2248 sitesym.name == names._super;
2249
2250 // If selected expression is polymorphic, strip
2251 // type parameters and remember in env.info.tvars, so that
2252 // they can be added later (in Attr.checkId and Infer.instantiateMethod).
2253 if (tree.selected.type.tag == FORALL) {
2254 ForAll pstype = (ForAll)tree.selected.type;
2255 env.info.tvars = pstype.tvars;
2256 site = tree.selected.type = pstype.qtype;
2257 }
2258
2259 // Determine the symbol represented by the selection.
2260 env.info.varArgs = false;
2261 Symbol sym = selectSym(tree, sitesym, site, env, pt, pkind);
2262 if (sym.exists() && !isType(sym) && (pkind & (PCK | TYP)) != 0) {
2263 site = capture(site);
2264 sym = selectSym(tree, sitesym, site, env, pt, pkind);
2265 }
2266 boolean varArgs = env.info.varArgs;
2267 tree.sym = sym;
2268
2269 if (site.tag == TYPEVAR && !isType(sym) && sym.kind != ERR) {
2270 while (site.tag == TYPEVAR) site = site.getUpperBound();
2271 site = capture(site);
2272 }
2273
2274 // If that symbol is a variable, ...
2275 if (sym.kind == VAR) {
2276 VarSymbol v = (VarSymbol)sym;
2277
2278 // ..., evaluate its initializer, if it has one, and check for
2279 // illegal forward reference.
2280 checkInit(tree, env, v, true);
2281
2282 // If we are expecting a variable (as opposed to a value), check
2283 // that the variable is assignable in the current environment.
2284 if (pkind == VAR)
2285 checkAssignable(tree.pos(), v, tree.selected, env);
2286 }
2287
2288 if (sitesym != null &&
2289 sitesym.kind == VAR &&
2290 ((VarSymbol)sitesym).isResourceVariable() &&
2291 sym.kind == MTH &&
2292 sym.overrides(syms.autoCloseableClose, sitesym.type.tsym, types, true) &&
2293 env.info.lint.isEnabled(LintCategory.TRY)) {
2294 log.warning(LintCategory.TRY, tree, "try.explicit.close.call");
2295 }
2296
2297 // Disallow selecting a type from an expression
2298 if (isType(sym) && (sitesym==null || (sitesym.kind&(TYP|PCK)) == 0)) {
2299 tree.type = check(tree.selected, pt,
2300 sitesym == null ? VAL : sitesym.kind, TYP|PCK, pt);
2301 }
2302
2303 if (isType(sitesym)) {
2304 if (sym.name == names._this) {
2305 // If `C' is the currently compiled class, check that
2306 // C.this' does not appear in a call to a super(...)
2307 if (env.info.isSelfCall &&
2308 site.tsym == env.enclClass.sym) {
2309 chk.earlyRefError(tree.pos(), sym);
2310 }
2311 } else {
2312 // Check if type-qualified fields or methods are static (JLS)
2313 if ((sym.flags() & STATIC) == 0 &&
2314 sym.name != names._super &&
2315 (sym.kind == VAR || sym.kind == MTH)) {
2316 rs.access(rs.new StaticError(sym),
2317 tree.pos(), site, sym.name, true);
2318 }
2319 }
2320 } else if (sym.kind != ERR && (sym.flags() & STATIC) != 0 && sym.name != names._class) {
2321 // If the qualified item is not a type and the selected item is static, report
2322 // a warning. Make allowance for the class of an array type e.g. Object[].class)
2323 chk.warnStatic(tree, "static.not.qualified.by.type", Kinds.kindName(sym.kind), sym.owner);
2324 }
2325
2326 // If we are selecting an instance member via a `super', ...
2327 if (env.info.selectSuper && (sym.flags() & STATIC) == 0) {
2328
2329 // Check that super-qualified symbols are not abstract (JLS)
2330 rs.checkNonAbstract(tree.pos(), sym);
2331
2332 if (site.isRaw()) {
2333 // Determine argument types for site.
2334 Type site1 = types.asSuper(env.enclClass.sym.type, site.tsym);
2335 if (site1 != null) site = site1;
2336 }
2337 }
2338
2339 env.info.selectSuper = selectSuperPrev;
2340 result = checkId(tree, site, sym, env, pkind, pt, varArgs);
2341 env.info.tvars = List.nil();
2342 }
2343 //where
2344 /** Determine symbol referenced by a Select expression,
2345 *
2346 * @param tree The select tree.
2347 * @param site The type of the selected expression,
2348 * @param env The current environment.
2349 * @param pt The current prototype.
2350 * @param pkind The expected kind(s) of the Select expression.
2351 */
2352 private Symbol selectSym(JCFieldAccess tree,
2353 Type site,
2354 Env<AttrContext> env,
2355 Type pt,
2356 int pkind) {
2357 return selectSym(tree, site.tsym, site, env, pt, pkind);
2358 }
2359 private Symbol selectSym(JCFieldAccess tree,
2360 Symbol location,
2361 Type site,
2362 Env<AttrContext> env,
2363 Type pt,
2364 int pkind) {
2365 DiagnosticPosition pos = tree.pos();
2366 Name name = tree.name;
2367 switch (site.tag) {
2368 case PACKAGE:
2369 return rs.access(
2370 rs.findIdentInPackage(env, site.tsym, name, pkind),
2371 pos, location, site, name, true);
2372 case ARRAY:
2373 case CLASS:
2374 if (pt.tag == METHOD || pt.tag == FORALL) {
2375 return rs.resolveQualifiedMethod(
2376 pos, env, location, site, name, pt.getParameterTypes(), pt.getTypeArguments());
2377 } else if (name == names._this || name == names._super) {
2378 return rs.resolveSelf(pos, env, site.tsym, name);
2379 } else if (name == names._class) {
2380 // In this case, we have already made sure in
2381 // visitSelect that qualifier expression is a type.
2382 Type t = syms.classType;
2383 List<Type> typeargs = allowGenerics
2384 ? List.of(types.erasure(site))
2385 : List.<Type>nil();
2386 t = new ClassType(t.getEnclosingType(), typeargs, t.tsym);
2387 return new VarSymbol(
2388 STATIC | PUBLIC | FINAL, names._class, t, site.tsym);
2389 } else {
2390 // We are seeing a plain identifier as selector.
2391 Symbol sym = rs.findIdentInType(env, site, name, pkind);
2392 if ((pkind & ERRONEOUS) == 0)
2393 sym = rs.access(sym, pos, location, site, name, true);
2394 return sym;
2395 }
2396 case WILDCARD:
2397 throw new AssertionError(tree);
2398 case TYPEVAR:
2399 // Normally, site.getUpperBound() shouldn't be null.
2400 // It should only happen during memberEnter/attribBase
2401 // when determining the super type which *must* beac
2402 // done before attributing the type variables. In
2403 // other words, we are seeing this illegal program:
2404 // class B<T> extends A<T.foo> {}
2405 Symbol sym = (site.getUpperBound() != null)
2406 ? selectSym(tree, location, capture(site.getUpperBound()), env, pt, pkind)
2407 : null;
2408 if (sym == null) {
2409 log.error(pos, "type.var.cant.be.deref");
2410 return syms.errSymbol;
2411 } else {
2412 Symbol sym2 = (sym.flags() & Flags.PRIVATE) != 0 ?
2413 rs.new AccessError(env, site, sym) :
2414 sym;
2415 rs.access(sym2, pos, location, site, name, true);
2416 return sym;
2417 }
2418 case ERROR:
2419 // preserve identifier names through errors
2420 return types.createErrorType(name, site.tsym, site).tsym;
2421 default:
2422 // The qualifier expression is of a primitive type -- only
2423 // .class is allowed for these.
2424 if (name == names._class) {
2425 // In this case, we have already made sure in Select that
2426 // qualifier expression is a type.
2427 Type t = syms.classType;
2428 Type arg = types.boxedClass(site).type;
2429 t = new ClassType(t.getEnclosingType(), List.of(arg), t.tsym);
2430 return new VarSymbol(
2431 STATIC | PUBLIC | FINAL, names._class, t, site.tsym);
2432 } else {
2433 log.error(pos, "cant.deref", site);
2434 return syms.errSymbol;
2435 }
2436 }
2437 }
2438
2439 /** Determine type of identifier or select expression and check that
2440 * (1) the referenced symbol is not deprecated
2441 * (2) the symbol's type is safe (@see checkSafe)
2442 * (3) if symbol is a variable, check that its type and kind are
2443 * compatible with the prototype and protokind.
2444 * (4) if symbol is an instance field of a raw type,
2445 * which is being assigned to, issue an unchecked warning if its
2446 * type changes under erasure.
2447 * (5) if symbol is an instance method of a raw type, issue an
2448 * unchecked warning if its argument types change under erasure.
2449 * If checks succeed:
2450 * If symbol is a constant, return its constant type
2451 * else if symbol is a method, return its result type
2452 * otherwise return its type.
2453 * Otherwise return errType.
2454 *
2455 * @param tree The syntax tree representing the identifier
2456 * @param site If this is a select, the type of the selected
2457 * expression, otherwise the type of the current class.
2458 * @param sym The symbol representing the identifier.
2459 * @param env The current environment.
2460 * @param pkind The set of expected kinds.
2461 * @param pt The expected type.
2462 */
2463 Type checkId(JCTree tree,
2464 Type site,
2465 Symbol sym,
2466 Env<AttrContext> env,
2467 int pkind,
2468 Type pt,
2469 boolean useVarargs) {
2470 if (pt.isErroneous()) return types.createErrorType(site);
2471 Type owntype; // The computed type of this identifier occurrence.
2472 switch (sym.kind) {
2473 case TYP:
2474 // For types, the computed type equals the symbol's type,
2475 // except for two situations:
2476 owntype = sym.type;
2477 if (owntype.tag == CLASS) {
2478 Type ownOuter = owntype.getEnclosingType();
2479
2480 // (a) If the symbol's type is parameterized, erase it
2481 // because no type parameters were given.
2482 // We recover generic outer type later in visitTypeApply.
2483 if (owntype.tsym.type.getTypeArguments().nonEmpty()) {
2484 owntype = types.erasure(owntype);
2485 }
2486
2487 // (b) If the symbol's type is an inner class, then
2488 // we have to interpret its outer type as a superclass
2489 // of the site type. Example:
2490 //
2491 // class Tree<A> { class Visitor { ... } }
2492 // class PointTree extends Tree<Point> { ... }
2493 // ...PointTree.Visitor...
2494 //
2495 // Then the type of the last expression above is
2496 // Tree<Point>.Visitor.
2497 else if (ownOuter.tag == CLASS && site != ownOuter) {
2498 Type normOuter = site;
2499 if (normOuter.tag == CLASS)
2500 normOuter = types.asEnclosingSuper(site, ownOuter.tsym);
2501 if (normOuter == null) // perhaps from an import
2502 normOuter = types.erasure(ownOuter);
2503 if (normOuter != ownOuter)
2504 owntype = new ClassType(
2505 normOuter, List.<Type>nil(), owntype.tsym);
2506 }
2507 }
2508 break;
2509 case VAR:
2510 VarSymbol v = (VarSymbol)sym;
2511 // Test (4): if symbol is an instance field of a raw type,
2512 // which is being assigned to, issue an unchecked warning if
2513 // its type changes under erasure.
2514 if (allowGenerics &&
2515 pkind == VAR &&
2516 v.owner.kind == TYP &&
2517 (v.flags() & STATIC) == 0 &&
2518 (site.tag == CLASS || site.tag == TYPEVAR)) {
2519 Type s = types.asOuterSuper(site, v.owner);
2520 if (s != null &&
2521 s.isRaw() &&
2522 !types.isSameType(v.type, v.erasure(types))) {
2523 chk.warnUnchecked(tree.pos(),
2524 "unchecked.assign.to.var",
2525 v, s);
2526 }
2527 }
2528 // The computed type of a variable is the type of the
2529 // variable symbol, taken as a member of the site type.
2530 owntype = (sym.owner.kind == TYP &&
2531 sym.name != names._this && sym.name != names._super)
2532 ? types.memberType(site, sym)
2533 : sym.type;
2534
2535 if (env.info.tvars.nonEmpty()) {
2536 Type owntype1 = new ForAll(env.info.tvars, owntype);
2537 for (List<Type> l = env.info.tvars; l.nonEmpty(); l = l.tail)
2538 if (!owntype.contains(l.head)) {
2539 log.error(tree.pos(), "undetermined.type", owntype1);
2540 owntype1 = types.createErrorType(owntype1);
2541 }
2542 owntype = owntype1;
2543 }
2544
2545 // If the variable is a constant, record constant value in
2546 // computed type.
2547 if (v.getConstValue() != null && isStaticReference(tree))
2548 owntype = owntype.constType(v.getConstValue());
2549
2550 if (pkind == VAL) {
2551 owntype = capture(owntype); // capture "names as expressions"
2552 }
2553 break;
2554 case MTH: {
2555 JCMethodInvocation app = (JCMethodInvocation)env.tree;
2556 owntype = checkMethod(site, sym, env, app.args,
2557 pt.getParameterTypes(), pt.getTypeArguments(),
2558 env.info.varArgs);
2559 break;
2560 }
2561 case PCK: case ERR:
2562 owntype = sym.type;
2563 break;
2564 default:
2565 throw new AssertionError("unexpected kind: " + sym.kind +
2566 " in tree " + tree);
2567 }
2568
2569 // Test (1): emit a `deprecation' warning if symbol is deprecated.
2570 // (for constructors, the error was given when the constructor was
2571 // resolved)
2572
2573 if (sym.name != names.init) {
2574 chk.checkDeprecated(tree.pos(), env.info.scope.owner, sym);
2575 chk.checkSunAPI(tree.pos(), sym);
2576 }
2577
2578 // Test (3): if symbol is a variable, check that its type and
2579 // kind are compatible with the prototype and protokind.
2580 return check(tree, owntype, sym.kind, pkind, pt);
2581 }
2582
2583 /** Check that variable is initialized and evaluate the variable's
2584 * initializer, if not yet done. Also check that variable is not
2585 * referenced before it is defined.
2586 * @param tree The tree making up the variable reference.
2587 * @param env The current environment.
2588 * @param v The variable's symbol.
2589 */
2590 private void checkInit(JCTree tree,
2591 Env<AttrContext> env,
2592 VarSymbol v,
2593 boolean onlyWarning) {
2594 // System.err.println(v + " " + ((v.flags() & STATIC) != 0) + " " +
2595 // tree.pos + " " + v.pos + " " +
2596 // Resolve.isStatic(env));//DEBUG
2597
2598 // A forward reference is diagnosed if the declaration position
2599 // of the variable is greater than the current tree position
2600 // and the tree and variable definition occur in the same class
2601 // definition. Note that writes don't count as references.
2602 // This check applies only to class and instance
2603 // variables. Local variables follow different scope rules,
2604 // and are subject to definite assignment checking.
2605 if ((env.info.enclVar == v || v.pos > tree.pos) &&
2606 v.owner.kind == TYP &&
2607 canOwnInitializer(env.info.scope.owner) &&
2608 v.owner == env.info.scope.owner.enclClass() &&
2609 ((v.flags() & STATIC) != 0) == Resolve.isStatic(env) &&
2610 (env.tree.getTag() != JCTree.ASSIGN ||
2611 TreeInfo.skipParens(((JCAssign) env.tree).lhs) != tree)) {
2612 String suffix = (env.info.enclVar == v) ?
2613 "self.ref" : "forward.ref";
2614 if (!onlyWarning || isStaticEnumField(v)) {
2615 log.error(tree.pos(), "illegal." + suffix);
2616 } else if (useBeforeDeclarationWarning) {
2617 log.warning(tree.pos(), suffix, v);
2618 }
2619 }
2620
2621 v.getConstValue(); // ensure initializer is evaluated
2622
2623 checkEnumInitializer(tree, env, v);
2624 }
2625
2626 /**
2627 * Check for illegal references to static members of enum. In
2628 * an enum type, constructors and initializers may not
2629 * reference its static members unless they are constant.
2630 *
2631 * @param tree The tree making up the variable reference.
2632 * @param env The current environment.
2633 * @param v The variable's symbol.
2634 * @see JLS 3rd Ed. (8.9 Enums)
2635 */
2636 private void checkEnumInitializer(JCTree tree, Env<AttrContext> env, VarSymbol v) {
2637 // JLS 3rd Ed.:
2638 //
2639 // "It is a compile-time error to reference a static field
2640 // of an enum type that is not a compile-time constant
2641 // (15.28) from constructors, instance initializer blocks,
2642 // or instance variable initializer expressions of that
2643 // type. It is a compile-time error for the constructors,
2644 // instance initializer blocks, or instance variable
2645 // initializer expressions of an enum constant e to refer
2646 // to itself or to an enum constant of the same type that
2647 // is declared to the right of e."
2648 if (isStaticEnumField(v)) {
2649 ClassSymbol enclClass = env.info.scope.owner.enclClass();
2650
2651 if (enclClass == null || enclClass.owner == null)
2652 return;
2653
2654 // See if the enclosing class is the enum (or a
2655 // subclass thereof) declaring v. If not, this
2656 // reference is OK.
2657 if (v.owner != enclClass && !types.isSubtype(enclClass.type, v.owner.type))
2658 return;
2659
2660 // If the reference isn't from an initializer, then
2661 // the reference is OK.
2662 if (!Resolve.isInitializer(env))
2663 return;
2664
2665 log.error(tree.pos(), "illegal.enum.static.ref");
2666 }
2667 }
2668
2669 /** Is the given symbol a static, non-constant field of an Enum?
2670 * Note: enum literals should not be regarded as such
2671 */
2672 private boolean isStaticEnumField(VarSymbol v) {
2673 return Flags.isEnum(v.owner) &&
2674 Flags.isStatic(v) &&
2675 !Flags.isConstant(v) &&
2676 v.name != names._class;
2677 }
2678
2679 /** Can the given symbol be the owner of code which forms part
2680 * if class initialization? This is the case if the symbol is
2681 * a type or field, or if the symbol is the synthetic method.
2682 * owning a block.
2683 */
2684 private boolean canOwnInitializer(Symbol sym) {
2685 return
2686 (sym.kind & (VAR | TYP)) != 0 ||
2687 (sym.kind == MTH && (sym.flags() & BLOCK) != 0);
2688 }
2689
2690 Warner noteWarner = new Warner();
2691
2692 /**
2693 * Check that method arguments conform to its instantation.
2694 **/
2695 public Type checkMethod(Type site,
2696 Symbol sym,
2697 Env<AttrContext> env,
2698 final List<JCExpression> argtrees,
2699 List<Type> argtypes,
2700 List<Type> typeargtypes,
2701 boolean useVarargs) {
2702 // Test (5): if symbol is an instance method of a raw type, issue
2703 // an unchecked warning if its argument types change under erasure.
2704 if (allowGenerics &&
2705 (sym.flags() & STATIC) == 0 &&
2706 (site.tag == CLASS || site.tag == TYPEVAR)) {
2707 Type s = types.asOuterSuper(site, sym.owner);
2708 if (s != null && s.isRaw() &&
2709 !types.isSameTypes(sym.type.getParameterTypes(),
2710 sym.erasure(types).getParameterTypes())) {
2711 chk.warnUnchecked(env.tree.pos(),
2712 "unchecked.call.mbr.of.raw.type",
2713 sym, s);
2714 }
2715 }
2716
2717 // Compute the identifier's instantiated type.
2718 // For methods, we need to compute the instance type by
2719 // Resolve.instantiate from the symbol's type as well as
2720 // any type arguments and value arguments.
2721 noteWarner.clear();
2722 Type owntype = rs.instantiate(env,
2723 site,
2724 sym,
2725 argtypes,
2726 typeargtypes,
2727 true,
2728 useVarargs,
2729 noteWarner);
2730 boolean warned = noteWarner.hasNonSilentLint(LintCategory.UNCHECKED);
2731
2732 // If this fails, something went wrong; we should not have
2733 // found the identifier in the first place.
2734 if (owntype == null) {
2735 if (!pt.isErroneous())
2736 log.error(env.tree.pos(),
2737 "internal.error.cant.instantiate",
2738 sym, site,
2739 Type.toString(pt.getParameterTypes()));
2740 owntype = types.createErrorType(site);
2741 } else {
2742 // System.out.println("call : " + env.tree);
2743 // System.out.println("method : " + owntype);
2744 // System.out.println("actuals: " + argtypes);
2745 List<Type> formals = owntype.getParameterTypes();
2746 Type last = useVarargs ? formals.last() : null;
2747 if (sym.name==names.init &&
2748 sym.owner == syms.enumSym)
2749 formals = formals.tail.tail;
2750 List<JCExpression> args = argtrees;
2751 while (formals.head != last) {
2752 JCTree arg = args.head;
2753 Warner warn = chk.convertWarner(arg.pos(), arg.type, formals.head);
2754 assertConvertible(arg, arg.type, formals.head, warn);
2755 warned |= warn.hasNonSilentLint(LintCategory.UNCHECKED);
2756 args = args.tail;
2757 formals = formals.tail;
2758 }
2759 if (useVarargs) {
2760 Type varArg = types.elemtype(last);
2761 while (args.tail != null) {
2762 JCTree arg = args.head;
2763 Warner warn = chk.convertWarner(arg.pos(), arg.type, varArg);
2764 assertConvertible(arg, arg.type, varArg, warn);
2765 warned |= warn.hasNonSilentLint(LintCategory.UNCHECKED);
2766 args = args.tail;
2767 }
2768 } else if ((sym.flags() & VARARGS) != 0 && allowVarargs) {
2769 // non-varargs call to varargs method
2770 Type varParam = owntype.getParameterTypes().last();
2771 Type lastArg = argtypes.last();
2772 if (types.isSubtypeUnchecked(lastArg, types.elemtype(varParam)) &&
2773 !types.isSameType(types.erasure(varParam), types.erasure(lastArg)))
2774 log.warning(argtrees.last().pos(), "inexact.non-varargs.call",
2775 types.elemtype(varParam),
2776 varParam);
2777 }
2778
2779 if (warned && sym.type.tag == FORALL) {
2780 chk.warnUnchecked(env.tree.pos(),
2781 "unchecked.meth.invocation.applied",
2782 kindName(sym),
2783 sym.name,
2784 rs.methodArguments(sym.type.getParameterTypes()),
2785 rs.methodArguments(argtypes),
2786 kindName(sym.location()),
2787 sym.location());
2788 owntype = new MethodType(owntype.getParameterTypes(),
2789 types.erasure(owntype.getReturnType()),
2790 types.erasure(owntype.getThrownTypes()),
2791 syms.methodClass);
2792 }
2793 if (useVarargs) {
2794 JCTree tree = env.tree;
2795 Type argtype = owntype.getParameterTypes().last();
2796 if (owntype.getReturnType().tag != FORALL || warned) {
2797 chk.checkVararg(env.tree.pos(), owntype.getParameterTypes(), sym);
2798 }
2799 Type elemtype = types.elemtype(argtype);
2800 switch (tree.getTag()) {
2801 case JCTree.APPLY:
2802 ((JCMethodInvocation) tree).varargsElement = elemtype;
2803 break;
2804 case JCTree.NEWCLASS:
2805 ((JCNewClass) tree).varargsElement = elemtype;
2806 break;
2807 default:
2808 throw new AssertionError(""+tree);
2809 }
2810 }
2811 }
2812 return owntype;
2813 }
2814
2815 private void assertConvertible(JCTree tree, Type actual, Type formal, Warner warn) {
2816 if (types.isConvertible(actual, formal, warn))
2817 return;
2818
2819 if (formal.isCompound()
2820 && types.isSubtype(actual, types.supertype(formal))
2821 && types.isSubtypeUnchecked(actual, types.interfaces(formal), warn))
2822 return;
2823
2824 if (false) {
2825 // TODO: make assertConvertible work
2826 chk.typeError(tree.pos(), diags.fragment("incompatible.types"), actual, formal);
2827 throw new AssertionError("Tree: " + tree
2828 + " actual:" + actual
2829 + " formal: " + formal);
2830 }
2831 }
2832
2833 public void visitLiteral(JCLiteral tree) {
2834 result = check(
2835 tree, litType(tree.typetag).constType(tree.value), VAL, pkind, pt);
2836 }
2837 //where
2838 /** Return the type of a literal with given type tag.
2839 */
2840 Type litType(int tag) {
2841 return (tag == TypeTags.CLASS) ? syms.stringType : syms.typeOfTag[tag];
2842 }
2843
2844 public void visitTypeIdent(JCPrimitiveTypeTree tree) {
2845 result = check(tree, syms.typeOfTag[tree.typetag], TYP, pkind, pt);
2846 }
2847
2848 public void visitTypeArray(JCArrayTypeTree tree) {
2849 Type etype = attribType(tree.elemtype, env);
2850 Type type = new ArrayType(etype, syms.arrayClass);
2851 result = check(tree, type, TYP, pkind, pt);
2852 }
2853
2854 /** Visitor method for parameterized types.
2855 * Bound checking is left until later, since types are attributed
2856 * before supertype structure is completely known
2857 */
2858 public void visitTypeApply(JCTypeApply tree) {
2859 Type owntype = types.createErrorType(tree.type);
2860
2861 // Attribute functor part of application and make sure it's a class.
2862 Type clazztype = chk.checkClassType(tree.clazz.pos(), attribType(tree.clazz, env));
2863
2864 // Attribute type parameters
2865 List<Type> actuals = attribTypes(tree.arguments, env);
2866
2867 if (clazztype.tag == CLASS) {
2868 List<Type> formals = clazztype.tsym.type.getTypeArguments();
2869
2870 if (actuals.length() == formals.length() || actuals.length() == 0) {
2871 List<Type> a = actuals;
2872 List<Type> f = formals;
2873 while (a.nonEmpty()) {
2874 a.head = a.head.withTypeVar(f.head);
2875 a = a.tail;
2876 f = f.tail;
2877 }
2878 // Compute the proper generic outer
2879 Type clazzOuter = clazztype.getEnclosingType();
2880 if (clazzOuter.tag == CLASS) {
2881 Type site;
2882 JCExpression clazz = TreeInfo.typeIn(tree.clazz);
2883 if (clazz.getTag() == JCTree.IDENT) {
2884 site = env.enclClass.sym.type;
2885 } else if (clazz.getTag() == JCTree.SELECT) {
2886 site = ((JCFieldAccess) clazz).selected.type;
2887 } else throw new AssertionError(""+tree);
2888 if (clazzOuter.tag == CLASS && site != clazzOuter) {
2889 if (site.tag == CLASS)
2890 site = types.asOuterSuper(site, clazzOuter.tsym);
2891 if (site == null)
2892 site = types.erasure(clazzOuter);
2893 clazzOuter = site;
2894 }
2895 }
2896 owntype = new ClassType(clazzOuter, actuals, clazztype.tsym);
2897 } else {
2898 if (formals.length() != 0) {
2899 log.error(tree.pos(), "wrong.number.type.args",
2900 Integer.toString(formals.length()));
2901 } else {
2902 log.error(tree.pos(), "type.doesnt.take.params", clazztype.tsym);
2903 }
2904 owntype = types.createErrorType(tree.type);
2905 }
2906 }
2907 result = check(tree, owntype, TYP, pkind, pt);
2908 }
2909
2910 public void visitTypeDisjunction(JCTypeDisjunction tree) {
2911 ListBuffer<Type> multicatchTypes = ListBuffer.lb();
2912 for (JCExpression typeTree : tree.alternatives) {
2913 Type ctype = attribType(typeTree, env);
2914 ctype = chk.checkType(typeTree.pos(),
2915 chk.checkClassType(typeTree.pos(), ctype),
2916 syms.throwableType);
2917 if (!ctype.isErroneous()) {
2918 //check that alternatives of a disjunctive type are pairwise
2919 //unrelated w.r.t. subtyping
2920 if (chk.intersects(ctype, multicatchTypes.toList())) {
2921 for (Type t : multicatchTypes) {
2922 boolean sub = types.isSubtype(ctype, t);
2923 boolean sup = types.isSubtype(t, ctype);
2924 if (sub || sup) {
2925 //assume 'a' <: 'b'
2926 Type a = sub ? ctype : t;
2927 Type b = sub ? t : ctype;
2928 log.error(typeTree.pos(), "multicatch.types.must.be.disjoint", a, b);
2929 }
2930 }
2931 }
2932 multicatchTypes.append(ctype);
2933 }
2934 }
2935 tree.type = result = check(tree, types.lub(multicatchTypes.toList()), TYP, pkind, pt);
2936 }
2937
2938 public void visitTypeParameter(JCTypeParameter tree) {
2939 TypeVar a = (TypeVar)tree.type;
2940 Set<Type> boundSet = new HashSet<Type>();
2941 if (a.bound.isErroneous())
2942 return;
2943 List<Type> bs = types.getBounds(a);
2944 if (tree.bounds.nonEmpty()) {
2945 // accept class or interface or typevar as first bound.
2946 Type b = checkBase(bs.head, tree.bounds.head, env, false, false, false);
2947 boundSet.add(types.erasure(b));
2948 if (b.isErroneous()) {
2949 a.bound = b;
2950 }
2951 else if (b.tag == TYPEVAR) {
2952 // if first bound was a typevar, do not accept further bounds.
2953 if (tree.bounds.tail.nonEmpty()) {
2954 log.error(tree.bounds.tail.head.pos(),
2955 "type.var.may.not.be.followed.by.other.bounds");
2956 tree.bounds = List.of(tree.bounds.head);
2957 a.bound = bs.head;
2958 }
2959 } else {
2960 // if first bound was a class or interface, accept only interfaces
2961 // as further bounds.
2962 for (JCExpression bound : tree.bounds.tail) {
2963 bs = bs.tail;
2964 Type i = checkBase(bs.head, bound, env, false, true, false);
2965 if (i.isErroneous())
2966 a.bound = i;
2967 else if (i.tag == CLASS)
2968 chk.checkNotRepeated(bound.pos(), types.erasure(i), boundSet);
2969 }
2970 }
2971 }
2972 bs = types.getBounds(a);
2973
2974 // in case of multiple bounds ...
2975 if (bs.length() > 1) {
2976 // ... the variable's bound is a class type flagged COMPOUND
2977 // (see comment for TypeVar.bound).
2978 // In this case, generate a class tree that represents the
2979 // bound class, ...
2980 JCExpression extending;
2981 List<JCExpression> implementing;
2982 if ((bs.head.tsym.flags() & INTERFACE) == 0) {
2983 extending = tree.bounds.head;
2984 implementing = tree.bounds.tail;
2985 } else {
2986 extending = null;
2987 implementing = tree.bounds;
2988 }
2989 JCClassDecl cd = make.at(tree.pos).ClassDef(
2990 make.Modifiers(PUBLIC | ABSTRACT),
2991 tree.name, List.<JCTypeParameter>nil(),
2992 extending, implementing, List.<JCTree>nil());
2993
2994 ClassSymbol c = (ClassSymbol)a.getUpperBound().tsym;
2995 Assert.check((c.flags() & COMPOUND) != 0);
2996 cd.sym = c;
2997 c.sourcefile = env.toplevel.sourcefile;
2998
2999 // ... and attribute the bound class
3000 c.flags_field |= UNATTRIBUTED;
3001 Env<AttrContext> cenv = enter.classEnv(cd, env);
3002 enter.typeEnvs.put(c, cenv);
3003 }
3004 }
3005
3006
3007 public void visitWildcard(JCWildcard tree) {
3008 //- System.err.println("visitWildcard("+tree+");");//DEBUG
3009 Type type = (tree.kind.kind == BoundKind.UNBOUND)
3010 ? syms.objectType
3011 : attribType(tree.inner, env);
3012 result = check(tree, new WildcardType(chk.checkRefType(tree.pos(), type),
3013 tree.kind.kind,
3014 syms.boundClass),
3015 TYP, pkind, pt);
3016 }
3017
3018 public void visitAnnotation(JCAnnotation tree) {
3019 log.error(tree.pos(), "annotation.not.valid.for.type", pt);
3020 result = tree.type = syms.errType;
3021 }
3022
3023 public void visitErroneous(JCErroneous tree) {
3024 if (tree.errs != null)
3025 for (JCTree err : tree.errs)
3026 attribTree(err, env, ERR, pt);
3027 result = tree.type = syms.errType;
3028 }
3029
3030 /** Default visitor method for all other trees.
3031 */
3032 public void visitTree(JCTree tree) {
3033 throw new AssertionError();
3034 }
3035
3036 /**
3037 * Attribute an env for either a top level tree or class declaration.
3038 */
3039 public void attrib(Env<AttrContext> env) {
3040 if (env.tree.getTag() == JCTree.TOPLEVEL)
3041 attribTopLevel(env);
3042 else
3043 attribClass(env.tree.pos(), env.enclClass.sym);
3044 }
3045
3046 /**
3047 * Attribute a top level tree. These trees are encountered when the
3048 * package declaration has annotations.
3049 */
3050 public void attribTopLevel(Env<AttrContext> env) {
3051 JCCompilationUnit toplevel = env.toplevel;
3052 try {
3053 annotate.flush();
3054 chk.validateAnnotations(toplevel.packageAnnotations, toplevel.packge);
3055 } catch (CompletionFailure ex) {
3056 chk.completionError(toplevel.pos(), ex);
3057 }
3058 }
3059
3060 /** Main method: attribute class definition associated with given class symbol.
3061 * reporting completion failures at the given position.
3062 * @param pos The source position at which completion errors are to be
3063 * reported.
3064 * @param c The class symbol whose definition will be attributed.
3065 */
3066 public void attribClass(DiagnosticPosition pos, ClassSymbol c) {
3067 try {
3068 annotate.flush();
3069 attribClass(c);
3070 } catch (CompletionFailure ex) {
3071 chk.completionError(pos, ex);
3072 }
3073 }
3074
3075 /** Attribute class definition associated with given class symbol.
3076 * @param c The class symbol whose definition will be attributed.
3077 */
3078 void attribClass(ClassSymbol c) throws CompletionFailure {
3079 if (c.type.tag == ERROR) return;
3080
3081 // Check for cycles in the inheritance graph, which can arise from
3082 // ill-formed class files.
3083 chk.checkNonCyclic(null, c.type);
3084
3085 Type st = types.supertype(c.type);
3086 if ((c.flags_field & Flags.COMPOUND) == 0) {
3087 // First, attribute superclass.
3088 if (st.tag == CLASS)
3089 attribClass((ClassSymbol)st.tsym);
3090
3091 // Next attribute owner, if it is a class.
3092 if (c.owner.kind == TYP && c.owner.type.tag == CLASS)
3093 attribClass((ClassSymbol)c.owner);
3094 }
3095
3096 // The previous operations might have attributed the current class
3097 // if there was a cycle. So we test first whether the class is still
3098 // UNATTRIBUTED.
3099 if ((c.flags_field & UNATTRIBUTED) != 0) {
3100 c.flags_field &= ~UNATTRIBUTED;
3101
3102 // Get environment current at the point of class definition.
3103 Env<AttrContext> env = enter.typeEnvs.get(c);
3104
3105 // The info.lint field in the envs stored in enter.typeEnvs is deliberately uninitialized,
3106 // because the annotations were not available at the time the env was created. Therefore,
3107 // we look up the environment chain for the first enclosing environment for which the
3108 // lint value is set. Typically, this is the parent env, but might be further if there
3109 // are any envs created as a result of TypeParameter nodes.
3110 Env<AttrContext> lintEnv = env;
3111 while (lintEnv.info.lint == null)
3112 lintEnv = lintEnv.next;
3113
3114 // Having found the enclosing lint value, we can initialize the lint value for this class
3115 env.info.lint = lintEnv.info.lint.augment(c.attributes_field, c.flags());
3116
3117 Lint prevLint = chk.setLint(env.info.lint);
3118 JavaFileObject prev = log.useSource(c.sourcefile);
3119
3120 try {
3121 // java.lang.Enum may not be subclassed by a non-enum
3122 if (st.tsym == syms.enumSym &&
3123 ((c.flags_field & (Flags.ENUM|Flags.COMPOUND)) == 0))
3124 log.error(env.tree.pos(), "enum.no.subclassing");
3125
3126 // Enums may not be extended by source-level classes
3127 if (st.tsym != null &&
3128 ((st.tsym.flags_field & Flags.ENUM) != 0) &&
3129 ((c.flags_field & (Flags.ENUM | Flags.COMPOUND)) == 0) &&
3130 !target.compilerBootstrap(c)) {
3131 log.error(env.tree.pos(), "enum.types.not.extensible");
3132 }
3133 attribClassBody(env, c);
3134
3135 chk.checkDeprecatedAnnotation(env.tree.pos(), c);
3136 } finally {
3137 log.useSource(prev);
3138 chk.setLint(prevLint);
3139 }
3140
3141 }
3142 }
3143
3144 public void visitImport(JCImport tree) {
3145 // nothing to do
3146 }
3147
3148 /** Finish the attribution of a class. */
3149 private void attribClassBody(Env<AttrContext> env, ClassSymbol c) {
3150 JCClassDecl tree = (JCClassDecl)env.tree;
3151 Assert.check(c == tree.sym);
3152
3153 // Validate annotations
3154 chk.validateAnnotations(tree.mods.annotations, c);
3155
3156 // Validate type parameters, supertype and interfaces.
3157 attribBounds(tree.typarams);
3158 if (!c.isAnonymous()) {
3159 //already checked if anonymous
3160 chk.validate(tree.typarams, env);
3161 chk.validate(tree.extending, env);
3162 chk.validate(tree.implementing, env);
3163 }
3164
3165 // If this is a non-abstract class, check that it has no abstract
3166 // methods or unimplemented methods of an implemented interface.
3167 if ((c.flags() & (ABSTRACT | INTERFACE)) == 0) {
3168 if (!relax)
3169 chk.checkAllDefined(tree.pos(), c);
3170 }
3171
3172 if ((c.flags() & ANNOTATION) != 0) {
3173 if (tree.implementing.nonEmpty())
3174 log.error(tree.implementing.head.pos(),
3175 "cant.extend.intf.annotation");
3176 if (tree.typarams.nonEmpty())
3177 log.error(tree.typarams.head.pos(),
3178 "intf.annotation.cant.have.type.params");
3179 } else {
3180 // Check that all extended classes and interfaces
3181 // are compatible (i.e. no two define methods with same arguments
3182 // yet different return types). (JLS 8.4.6.3)
3183 chk.checkCompatibleSupertypes(tree.pos(), c.type);
3184 }
3185
3186 // Check that class does not import the same parameterized interface
3187 // with two different argument lists.
3188 chk.checkClassBounds(tree.pos(), c.type);
3189
3190 tree.type = c.type;
3191
3192 for (List<JCTypeParameter> l = tree.typarams;
3193 l.nonEmpty(); l = l.tail) {
3194 Assert.checkNonNull(env.info.scope.lookup(l.head.name).scope);
3195 }
3196
3197 // Check that a generic class doesn't extend Throwable
3198 if (!c.type.allparams().isEmpty() && types.isSubtype(c.type, syms.throwableType))
3199 log.error(tree.extending.pos(), "generic.throwable");
3200
3201 // Check that all methods which implement some
3202 // method conform to the method they implement.
3203 chk.checkImplementations(tree);
3204
3205 //check that a resource implementing AutoCloseable cannot throw InterruptedException
3206 checkAutoCloseable(tree.pos(), env, c.type);
3207
3208 for (List<JCTree> l = tree.defs; l.nonEmpty(); l = l.tail) {
3209 // Attribute declaration
3210 attribStat(l.head, env);
3211 // Check that declarations in inner classes are not static (JLS 8.1.2)
3212 // Make an exception for static constants.
3213 if (c.owner.kind != PCK &&
3214 ((c.flags() & STATIC) == 0 || c.name == names.empty) &&
3215 (TreeInfo.flags(l.head) & (STATIC | INTERFACE)) != 0) {
3216 Symbol sym = null;
3217 if (l.head.getTag() == JCTree.VARDEF) sym = ((JCVariableDecl) l.head).sym;
3218 if (sym == null ||
3219 sym.kind != VAR ||
3220 ((VarSymbol) sym).getConstValue() == null)
3221 log.error(l.head.pos(), "icls.cant.have.static.decl", c);
3222 }
3223 }
3224
3225 // Check for cycles among non-initial constructors.
3226 chk.checkCyclicConstructors(tree);
3227
3228 // Check for cycles among annotation elements.
3229 chk.checkNonCyclicElements(tree);
3230
3231 // Check for proper use of serialVersionUID
3232 if (env.info.lint.isEnabled(LintCategory.SERIAL) &&
3233 isSerializable(c) &&
3234 (c.flags() & Flags.ENUM) == 0 &&
3235 (c.flags() & ABSTRACT) == 0) {
3236 checkSerialVersionUID(tree, c);
3237 }
3238 }
3239 // where
3240 /** check if a class is a subtype of Serializable, if that is available. */
3241 private boolean isSerializable(ClassSymbol c) {
3242 try {
3243 syms.serializableType.complete();
3244 }
3245 catch (CompletionFailure e) {
3246 return false;
3247 }
3248 return types.isSubtype(c.type, syms.serializableType);
3249 }
3250
3251 /** Check that an appropriate serialVersionUID member is defined. */
3252 private void checkSerialVersionUID(JCClassDecl tree, ClassSymbol c) {
3253
3254 // check for presence of serialVersionUID
3255 Scope.Entry e = c.members().lookup(names.serialVersionUID);
3256 while (e.scope != null && e.sym.kind != VAR) e = e.next();
3257 if (e.scope == null) {
3258 log.warning(LintCategory.SERIAL,
3259 tree.pos(), "missing.SVUID", c);
3260 return;
3261 }
3262
3263 // check that it is static final
3264 VarSymbol svuid = (VarSymbol)e.sym;
3265 if ((svuid.flags() & (STATIC | FINAL)) !=
3266 (STATIC | FINAL))
3267 log.warning(LintCategory.SERIAL,
3268 TreeInfo.diagnosticPositionFor(svuid, tree), "improper.SVUID", c);
3269
3270 // check that it is long
3271 else if (svuid.type.tag != TypeTags.LONG)
3272 log.warning(LintCategory.SERIAL,
3273 TreeInfo.diagnosticPositionFor(svuid, tree), "long.SVUID", c);
3274
3275 // check constant
3276 else if (svuid.getConstValue() == null)
3277 log.warning(LintCategory.SERIAL,
3278 TreeInfo.diagnosticPositionFor(svuid, tree), "constant.SVUID", c);
3279 }
3280
3281 private Type capture(Type type) {
3282 return types.capture(type);
3283 }
3284
3285 // <editor-fold desc="post-attribution visitor">
3286
3287 /**
3288 * Handle missing types/symbols in an AST. This routine is useful when
3289 * the compiler has encountered some errors (which might have ended up
3290 * terminating attribution abruptly); if the compiler is used in fail-over
3291 * mode (e.g. by an IDE) and the AST contains semantic errors, this routine
3292 * prevents NPE to be progagated during subsequent compilation steps.
3293 */
3294 public void postAttr(Env<AttrContext> env) {
3295 new PostAttrAnalyzer().scan(env.tree);
3296 }
3297
3298 class PostAttrAnalyzer extends TreeScanner {
3299
3300 private void initTypeIfNeeded(JCTree that) {
3301 if (that.type == null) {
3302 that.type = syms.unknownType;
3303 }
3304 }
3305
3306 @Override
3307 public void scan(JCTree tree) {
3308 if (tree == null) return;
3309 if (tree instanceof JCExpression) {
3310 initTypeIfNeeded(tree);
3311 }
3312 super.scan(tree);
3313 }
3314
3315 @Override
3316 public void visitIdent(JCIdent that) {
3317 if (that.sym == null) {
3318 that.sym = syms.unknownSymbol;
3319 }
3320 }
3321
3322 @Override
3323 public void visitSelect(JCFieldAccess that) {
3324 if (that.sym == null) {
3325 that.sym = syms.unknownSymbol;
3326 }
3327 super.visitSelect(that);
3328 }
3329
3330 @Override
3331 public void visitClassDef(JCClassDecl that) {
3332 initTypeIfNeeded(that);
3333 if (that.sym == null) {
3334 that.sym = new ClassSymbol(0, that.name, that.type, syms.noSymbol);
3335 }
3336 super.visitClassDef(that);
3337 }
3338
3339 @Override
3340 public void visitMethodDef(JCMethodDecl that) {
3341 initTypeIfNeeded(that);
3342 if (that.sym == null) {
3343 that.sym = new MethodSymbol(0, that.name, that.type, syms.noSymbol);
3344 }
3345 super.visitMethodDef(that);
3346 }
3347
3348 @Override
3349 public void visitVarDef(JCVariableDecl that) {
3350 initTypeIfNeeded(that);
3351 if (that.sym == null) {
3352 that.sym = new VarSymbol(0, that.name, that.type, syms.noSymbol);
3353 that.sym.adr = 0;
3354 }
3355 super.visitVarDef(that);
3356 }
3357
3358 @Override
3359 public void visitNewClass(JCNewClass that) {
3360 if (that.constructor == null) {
3361 that.constructor = new MethodSymbol(0, names.init, syms.unknownType, syms.noSymbol);
3362 }
3363 if (that.constructorType == null) {
3364 that.constructorType = syms.unknownType;
3365 }
3366 super.visitNewClass(that);
3367 }
3368
3369 @Override
3370 public void visitBinary(JCBinary that) {
3371 if (that.operator == null)
3372 that.operator = new OperatorSymbol(names.empty, syms.unknownType, -1, syms.noSymbol);
3373 super.visitBinary(that);
3374 }
3375
3376 @Override
3377 public void visitUnary(JCUnary that) {
3378 if (that.operator == null)
3379 that.operator = new OperatorSymbol(names.empty, syms.unknownType, -1, syms.noSymbol);
3380 super.visitUnary(that);
3381 }
3382 }
3383 // </editor-fold>
3384 }