1 /*
2 * Copyright (c) 1999, 2013, 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
30 import javax.lang.model.element.ElementKind;
31 import javax.lang.model.type.TypeKind;
32 import javax.tools.JavaFileObject;
33
34 import com.sun.source.tree.IdentifierTree;
35 import com.sun.source.tree.MemberReferenceTree.ReferenceMode;
36 import com.sun.source.tree.MemberSelectTree;
37 import com.sun.source.tree.TreeVisitor;
38 import com.sun.source.util.SimpleTreeVisitor;
39 import com.sun.tools.javac.code.*;
40 import com.sun.tools.javac.code.Lint.LintCategory;
41 import com.sun.tools.javac.code.Symbol.*;
42 import com.sun.tools.javac.code.Type.*;
43 import com.sun.tools.javac.comp.Check.CheckContext;
44 import com.sun.tools.javac.comp.DeferredAttr.AttrMode;
45 import com.sun.tools.javac.comp.Infer.InferenceContext;
46 import com.sun.tools.javac.comp.Infer.FreeTypeListener;
47 import com.sun.tools.javac.jvm.*;
48 import com.sun.tools.javac.tree.*;
49 import com.sun.tools.javac.tree.JCTree.*;
50 import com.sun.tools.javac.tree.JCTree.JCPolyExpression.*;
51 import com.sun.tools.javac.util.*;
52 import com.sun.tools.javac.util.JCDiagnostic.DiagnosticPosition;
53 import com.sun.tools.javac.util.List;
54 import static com.sun.tools.javac.code.Flags.*;
55 import static com.sun.tools.javac.code.Flags.ANNOTATION;
56 import static com.sun.tools.javac.code.Flags.BLOCK;
57 import static com.sun.tools.javac.code.Kinds.*;
58 import static com.sun.tools.javac.code.Kinds.ERRONEOUS;
59 import static com.sun.tools.javac.code.TypeTag.*;
60 import static com.sun.tools.javac.code.TypeTag.WILDCARD;
61 import static com.sun.tools.javac.tree.JCTree.Tag.*;
62
63 /** This is the main context-dependent analysis phase in GJC. It
64 * encompasses name resolution, type checking and constant folding as
65 * subtasks. Some subtasks involve auxiliary classes.
66 * @see Check
67 * @see Resolve
68 * @see ConstFold
69 * @see Infer
70 *
71 * <p><b>This is NOT part of any supported API.
72 * If you write code that depends on this, you do so at your own risk.
73 * This code and its internal interfaces are subject to change or
74 * deletion without notice.</b>
75 */
76 public class Attr extends JCTree.Visitor {
77 protected static final Context.Key<Attr> attrKey =
78 new Context.Key<Attr>();
79
80 final Names names;
81 final Log log;
82 final Symtab syms;
83 final Resolve rs;
84 final Infer infer;
85 final DeferredAttr deferredAttr;
86 final Check chk;
87 final Flow flow;
88 final MemberEnter memberEnter;
89 final TreeMaker make;
90 final ConstFold cfolder;
91 final Enter enter;
92 final Target target;
93 final Types types;
94 final JCDiagnostic.Factory diags;
95 final Annotate annotate;
96 final DeferredLintHandler deferredLintHandler;
97
98 public static Attr instance(Context context) {
99 Attr instance = context.get(attrKey);
100 if (instance == null)
101 instance = new Attr(context);
102 return instance;
103 }
104
105 protected Attr(Context context) {
106 context.put(attrKey, this);
107
108 names = Names.instance(context);
109 log = Log.instance(context);
110 syms = Symtab.instance(context);
111 rs = Resolve.instance(context);
112 chk = Check.instance(context);
113 flow = Flow.instance(context);
114 memberEnter = MemberEnter.instance(context);
115 make = TreeMaker.instance(context);
116 enter = Enter.instance(context);
117 infer = Infer.instance(context);
118 deferredAttr = DeferredAttr.instance(context);
119 cfolder = ConstFold.instance(context);
120 target = Target.instance(context);
121 types = Types.instance(context);
122 diags = JCDiagnostic.Factory.instance(context);
123 annotate = Annotate.instance(context);
124 deferredLintHandler = DeferredLintHandler.instance(context);
125
126 Options options = Options.instance(context);
127
128 Source source = Source.instance(context);
129 allowGenerics = source.allowGenerics();
130 allowVarargs = source.allowVarargs();
131 allowEnums = source.allowEnums();
132 allowBoxing = source.allowBoxing();
133 allowCovariantReturns = source.allowCovariantReturns();
134 allowAnonOuterThis = source.allowAnonOuterThis();
135 allowStringsInSwitch = source.allowStringsInSwitch();
136 allowPoly = source.allowPoly();
137 allowLambda = source.allowLambda();
138 allowDefaultMethods = source.allowDefaultMethods();
139 sourceName = source.name;
140 relax = (options.isSet("-retrofit") ||
141 options.isSet("-relax"));
142 findDiamonds = options.get("findDiamond") != null &&
143 source.allowDiamond();
144 useBeforeDeclarationWarning = options.isSet("useBeforeDeclarationWarning");
145 identifyLambdaCandidate = options.getBoolean("identifyLambdaCandidate", false);
146
147 statInfo = new ResultInfo(NIL, Type.noType);
148 varInfo = new ResultInfo(VAR, Type.noType);
149 unknownExprInfo = new ResultInfo(VAL, Type.noType);
150 unknownTypeInfo = new ResultInfo(TYP, Type.noType);
151 unknownTypeExprInfo = new ResultInfo(Kinds.TYP | Kinds.VAL, Type.noType);
152 recoveryInfo = new RecoveryInfo(deferredAttr.emptyDeferredAttrContext);
153 }
154
155 /** Switch: relax some constraints for retrofit mode.
156 */
157 boolean relax;
158
159 /** Switch: support target-typing inference
160 */
161 boolean allowPoly;
162
163 /** Switch: support generics?
164 */
165 boolean allowGenerics;
166
167 /** Switch: allow variable-arity methods.
168 */
169 boolean allowVarargs;
170
171 /** Switch: support enums?
172 */
173 boolean allowEnums;
174
175 /** Switch: support boxing and unboxing?
176 */
177 boolean allowBoxing;
178
179 /** Switch: support covariant result types?
180 */
181 boolean allowCovariantReturns;
182
183 /** Switch: support lambda expressions ?
184 */
185 boolean allowLambda;
186
187 /** Switch: support default methods ?
188 */
189 boolean allowDefaultMethods;
190
191 /** Switch: allow references to surrounding object from anonymous
192 * objects during constructor call?
193 */
194 boolean allowAnonOuterThis;
195
196 /** Switch: generates a warning if diamond can be safely applied
197 * to a given new expression
198 */
199 boolean findDiamonds;
200
201 /**
202 * Internally enables/disables diamond finder feature
203 */
204 static final boolean allowDiamondFinder = true;
205
206 /**
207 * Switch: warn about use of variable before declaration?
208 * RFE: 6425594
209 */
210 boolean useBeforeDeclarationWarning;
211
212 /**
213 * Switch: generate warnings whenever an anonymous inner class that is convertible
214 * to a lambda expression is found
215 */
216 boolean identifyLambdaCandidate;
217
218 /**
219 * Switch: allow strings in switch?
220 */
221 boolean allowStringsInSwitch;
222
223 /**
224 * Switch: name of source level; used for error reporting.
225 */
226 String sourceName;
227
228 /** Check kind and type of given tree against protokind and prototype.
229 * If check succeeds, store type in tree and return it.
230 * If check fails, store errType in tree and return it.
231 * No checks are performed if the prototype is a method type.
232 * It is not necessary in this case since we know that kind and type
233 * are correct.
234 *
235 * @param tree The tree whose kind and type is checked
236 * @param ownkind The computed kind of the tree
237 * @param resultInfo The expected result of the tree
238 */
239 Type check(final JCTree tree, final Type found, final int ownkind, final ResultInfo resultInfo) {
240 InferenceContext inferenceContext = resultInfo.checkContext.inferenceContext();
241 Type owntype = found;
242 if (!owntype.hasTag(ERROR) && !resultInfo.pt.hasTag(METHOD) && !resultInfo.pt.hasTag(FORALL)) {
243 if (inferenceContext.free(found)) {
244 inferenceContext.addFreeTypeListener(List.of(found, resultInfo.pt), new FreeTypeListener() {
245 @Override
246 public void typesInferred(InferenceContext inferenceContext) {
247 ResultInfo pendingResult =
248 resultInfo.dup(inferenceContext.asInstType(resultInfo.pt));
249 check(tree, inferenceContext.asInstType(found), ownkind, pendingResult);
250 }
251 });
252 return tree.type = resultInfo.pt;
253 } else {
254 if ((ownkind & ~resultInfo.pkind) == 0) {
255 owntype = resultInfo.check(tree, owntype);
256 } else {
257 log.error(tree.pos(), "unexpected.type",
258 kindNames(resultInfo.pkind),
259 kindName(ownkind));
260 owntype = types.createErrorType(owntype);
261 }
262 }
263 }
264 tree.type = owntype;
265 return owntype;
266 }
267
268 /** Is given blank final variable assignable, i.e. in a scope where it
269 * may be assigned to even though it is final?
270 * @param v The blank final variable.
271 * @param env The current environment.
272 */
273 boolean isAssignableAsBlankFinal(VarSymbol v, Env<AttrContext> env) {
274 Symbol owner = owner(env);
275 // owner refers to the innermost variable, method or
276 // initializer block declaration at this point.
277 return
278 v.owner == owner
279 ||
280 ((owner.name == names.init || // i.e. we are in a constructor
281 owner.kind == VAR || // i.e. we are in a variable initializer
282 (owner.flags() & BLOCK) != 0) // i.e. we are in an initializer block
283 &&
284 v.owner == owner.owner
285 &&
286 ((v.flags() & STATIC) != 0) == Resolve.isStatic(env));
287 }
288
289 /**
290 * Return the innermost enclosing owner symbol in a given attribution context
291 */
292 Symbol owner(Env<AttrContext> env) {
293 while (true) {
294 switch (env.tree.getTag()) {
295 case VARDEF:
296 //a field can be owner
297 VarSymbol vsym = ((JCVariableDecl)env.tree).sym;
298 if (vsym.owner.kind == TYP) {
299 return vsym;
300 }
301 break;
302 case METHODDEF:
303 //method def is always an owner
304 return ((JCMethodDecl)env.tree).sym;
305 case CLASSDEF:
306 //class def is always an owner
307 return ((JCClassDecl)env.tree).sym;
308 case LAMBDA:
309 //a lambda is an owner - return a fresh synthetic method symbol
310 return new MethodSymbol(0, names.empty, null, syms.methodClass);
311 case BLOCK:
312 //static/instance init blocks are owner
313 Symbol blockSym = env.info.scope.owner;
314 if ((blockSym.flags() & BLOCK) != 0) {
315 return blockSym;
316 }
317 break;
318 case TOPLEVEL:
319 //toplevel is always an owner (for pkge decls)
320 return env.info.scope.owner;
321 }
322 Assert.checkNonNull(env.next);
323 env = env.next;
324 }
325 }
326
327 /** Check that variable can be assigned to.
328 * @param pos The current source code position.
329 * @param v The assigned varaible
330 * @param base If the variable is referred to in a Select, the part
331 * to the left of the `.', null otherwise.
332 * @param env The current environment.
333 */
334 void checkAssignable(DiagnosticPosition pos, VarSymbol v, JCTree base, Env<AttrContext> env) {
335 if ((v.flags() & FINAL) != 0 &&
336 ((v.flags() & HASINIT) != 0
337 ||
338 !((base == null ||
339 (base.hasTag(IDENT) && TreeInfo.name(base) == names._this)) &&
340 isAssignableAsBlankFinal(v, env)))) {
341 if (v.isResourceVariable()) { //TWR resource
342 log.error(pos, "try.resource.may.not.be.assigned", v);
343 } else {
344 log.error(pos, "cant.assign.val.to.final.var", v);
345 }
346 }
347 }
348
349 /** Does tree represent a static reference to an identifier?
350 * It is assumed that tree is either a SELECT or an IDENT.
351 * We have to weed out selects from non-type names here.
352 * @param tree The candidate tree.
353 */
354 boolean isStaticReference(JCTree tree) {
355 if (tree.hasTag(SELECT)) {
356 Symbol lsym = TreeInfo.symbol(((JCFieldAccess) tree).selected);
357 if (lsym == null || lsym.kind != TYP) {
358 return false;
359 }
360 }
361 return true;
362 }
363
364 /** Is this symbol a type?
365 */
366 static boolean isType(Symbol sym) {
367 return sym != null && sym.kind == TYP;
368 }
369
370 /** The current `this' symbol.
371 * @param env The current environment.
372 */
373 Symbol thisSym(DiagnosticPosition pos, Env<AttrContext> env) {
374 return rs.resolveSelf(pos, env, env.enclClass.sym, names._this);
375 }
376
377 /** Attribute a parsed identifier.
378 * @param tree Parsed identifier name
379 * @param topLevel The toplevel to use
380 */
381 public Symbol attribIdent(JCTree tree, JCCompilationUnit topLevel) {
382 Env<AttrContext> localEnv = enter.topLevelEnv(topLevel);
383 localEnv.enclClass = make.ClassDef(make.Modifiers(0),
384 syms.errSymbol.name,
385 null, null, null, null);
386 localEnv.enclClass.sym = syms.errSymbol;
387 return tree.accept(identAttributer, localEnv);
388 }
389 // where
390 private TreeVisitor<Symbol,Env<AttrContext>> identAttributer = new IdentAttributer();
391 private class IdentAttributer extends SimpleTreeVisitor<Symbol,Env<AttrContext>> {
392 @Override
393 public Symbol visitMemberSelect(MemberSelectTree node, Env<AttrContext> env) {
394 Symbol site = visit(node.getExpression(), env);
395 if (site.kind == ERR)
396 return site;
397 Name name = (Name)node.getIdentifier();
398 if (site.kind == PCK) {
399 env.toplevel.packge = (PackageSymbol)site;
400 return rs.findIdentInPackage(env, (TypeSymbol)site, name, TYP | PCK);
401 } else {
402 env.enclClass.sym = (ClassSymbol)site;
403 return rs.findMemberType(env, site.asType(), name, (TypeSymbol)site);
404 }
405 }
406
407 @Override
408 public Symbol visitIdentifier(IdentifierTree node, Env<AttrContext> env) {
409 return rs.findIdent(env, (Name)node.getName(), TYP | PCK);
410 }
411 }
412
413 public Type coerce(Type etype, Type ttype) {
414 return cfolder.coerce(etype, ttype);
415 }
416
417 public Type attribType(JCTree node, TypeSymbol sym) {
418 Env<AttrContext> env = enter.typeEnvs.get(sym);
419 Env<AttrContext> localEnv = env.dup(node, env.info.dup());
420 return attribTree(node, localEnv, unknownTypeInfo);
421 }
422
423 public Type attribImportQualifier(JCImport tree, Env<AttrContext> env) {
424 // Attribute qualifying package or class.
425 JCFieldAccess s = (JCFieldAccess)tree.qualid;
426 return attribTree(s.selected,
427 env,
428 new ResultInfo(tree.staticImport ? TYP : (TYP | PCK),
429 Type.noType));
430 }
431
432 public Env<AttrContext> attribExprToTree(JCTree expr, Env<AttrContext> env, JCTree tree) {
433 breakTree = tree;
434 JavaFileObject prev = log.useSource(env.toplevel.sourcefile);
435 try {
436 attribExpr(expr, env);
437 } catch (BreakAttr b) {
438 return b.env;
439 } catch (AssertionError ae) {
440 if (ae.getCause() instanceof BreakAttr) {
441 return ((BreakAttr)(ae.getCause())).env;
442 } else {
443 throw ae;
444 }
445 } finally {
446 breakTree = null;
447 log.useSource(prev);
448 }
449 return env;
450 }
451
452 public Env<AttrContext> attribStatToTree(JCTree stmt, Env<AttrContext> env, JCTree tree) {
453 breakTree = tree;
454 JavaFileObject prev = log.useSource(env.toplevel.sourcefile);
455 try {
456 attribStat(stmt, env);
457 } catch (BreakAttr b) {
458 return b.env;
459 } catch (AssertionError ae) {
460 if (ae.getCause() instanceof BreakAttr) {
461 return ((BreakAttr)(ae.getCause())).env;
462 } else {
463 throw ae;
464 }
465 } finally {
466 breakTree = null;
467 log.useSource(prev);
468 }
469 return env;
470 }
471
472 private JCTree breakTree = null;
473
474 private static class BreakAttr extends RuntimeException {
475 static final long serialVersionUID = -6924771130405446405L;
476 private Env<AttrContext> env;
477 private BreakAttr(Env<AttrContext> env) {
478 this.env = copyEnv(env);
479 }
480
481 private Env<AttrContext> copyEnv(Env<AttrContext> env) {
482 Env<AttrContext> newEnv =
483 env.dup(env.tree, env.info.dup(copyScope(env.info.scope)));
484 if (newEnv.outer != null) {
485 newEnv.outer = copyEnv(newEnv.outer);
486 }
487 return newEnv;
488 }
489
490 private Scope copyScope(Scope sc) {
491 Scope newScope = new Scope(sc.owner);
492 List<Symbol> elemsList = List.nil();
493 while (sc != null) {
494 for (Scope.Entry e = sc.elems ; e != null ; e = e.sibling) {
495 elemsList = elemsList.prepend(e.sym);
496 }
497 sc = sc.next;
498 }
499 for (Symbol s : elemsList) {
500 newScope.enter(s);
501 }
502 return newScope;
503 }
504 }
505
506 class ResultInfo {
507 final int pkind;
508 final Type pt;
509 final CheckContext checkContext;
510
511 ResultInfo(int pkind, Type pt) {
512 this(pkind, pt, chk.basicHandler);
513 }
514
515 protected ResultInfo(int pkind, Type pt, CheckContext checkContext) {
516 this.pkind = pkind;
517 this.pt = pt;
518 this.checkContext = checkContext;
519 }
520
521 protected Type check(final DiagnosticPosition pos, final Type found) {
522 return chk.checkType(pos, found, pt, checkContext);
523 }
524
525 protected ResultInfo dup(Type newPt) {
526 return new ResultInfo(pkind, newPt, checkContext);
527 }
528
529 protected ResultInfo dup(CheckContext newContext) {
530 return new ResultInfo(pkind, pt, newContext);
531 }
532 }
533
534 class RecoveryInfo extends ResultInfo {
535
536 public RecoveryInfo(final DeferredAttr.DeferredAttrContext deferredAttrContext) {
537 super(Kinds.VAL, Type.recoveryType, new Check.NestedCheckContext(chk.basicHandler) {
538 @Override
539 public DeferredAttr.DeferredAttrContext deferredAttrContext() {
540 return deferredAttrContext;
541 }
542 @Override
543 public boolean compatible(Type found, Type req, Warner warn) {
544 return true;
545 }
546 @Override
547 public void report(DiagnosticPosition pos, JCDiagnostic details) {
548 chk.basicHandler.report(pos, details);
549 }
550 });
551 }
552
553 @Override
554 protected Type check(DiagnosticPosition pos, Type found) {
555 return chk.checkNonVoid(pos, super.check(pos, found));
556 }
557 }
558
559 final ResultInfo statInfo;
560 final ResultInfo varInfo;
561 final ResultInfo unknownExprInfo;
562 final ResultInfo unknownTypeInfo;
563 final ResultInfo unknownTypeExprInfo;
564 final ResultInfo recoveryInfo;
565
566 Type pt() {
567 return resultInfo.pt;
568 }
569
570 int pkind() {
571 return resultInfo.pkind;
572 }
573
574 /* ************************************************************************
575 * Visitor methods
576 *************************************************************************/
577
578 /** Visitor argument: the current environment.
579 */
580 Env<AttrContext> env;
581
582 /** Visitor argument: the currently expected attribution result.
583 */
584 ResultInfo resultInfo;
585
586 /** Visitor result: the computed type.
587 */
588 Type result;
589
590 /** Visitor method: attribute a tree, catching any completion failure
591 * exceptions. Return the tree's type.
592 *
593 * @param tree The tree to be visited.
594 * @param env The environment visitor argument.
595 * @param resultInfo The result info visitor argument.
596 */
597 Type attribTree(JCTree tree, Env<AttrContext> env, ResultInfo resultInfo) {
598 Env<AttrContext> prevEnv = this.env;
599 ResultInfo prevResult = this.resultInfo;
600 try {
601 this.env = env;
602 this.resultInfo = resultInfo;
603 tree.accept(this);
604 if (tree == breakTree &&
605 resultInfo.checkContext.deferredAttrContext().mode == AttrMode.CHECK) {
606 throw new BreakAttr(env);
607 }
608 return result;
609 } catch (CompletionFailure ex) {
610 tree.type = syms.errType;
611 return chk.completionError(tree.pos(), ex);
612 } finally {
613 this.env = prevEnv;
614 this.resultInfo = prevResult;
615 }
616 }
617
618 /** Derived visitor method: attribute an expression tree.
619 */
620 public Type attribExpr(JCTree tree, Env<AttrContext> env, Type pt) {
621 return attribTree(tree, env, new ResultInfo(VAL, !pt.hasTag(ERROR) ? pt : Type.noType));
622 }
623
624 /** Derived visitor method: attribute an expression tree with
625 * no constraints on the computed type.
626 */
627 public Type attribExpr(JCTree tree, Env<AttrContext> env) {
628 return attribTree(tree, env, unknownExprInfo);
629 }
630
631 /** Derived visitor method: attribute a type tree.
632 */
633 public Type attribType(JCTree tree, Env<AttrContext> env) {
634 Type result = attribType(tree, env, Type.noType);
635 return result;
636 }
637
638 /** Derived visitor method: attribute a type tree.
639 */
640 Type attribType(JCTree tree, Env<AttrContext> env, Type pt) {
641 Type result = attribTree(tree, env, new ResultInfo(TYP, pt));
642 return result;
643 }
644
645 /** Derived visitor method: attribute a statement or definition tree.
646 */
647 public Type attribStat(JCTree tree, Env<AttrContext> env) {
648 return attribTree(tree, env, statInfo);
649 }
650
651 /** Attribute a list of expressions, returning a list of types.
652 */
653 List<Type> attribExprs(List<JCExpression> trees, Env<AttrContext> env, Type pt) {
654 ListBuffer<Type> ts = new ListBuffer<Type>();
655 for (List<JCExpression> l = trees; l.nonEmpty(); l = l.tail)
656 ts.append(attribExpr(l.head, env, pt));
657 return ts.toList();
658 }
659
660 /** Attribute a list of statements, returning nothing.
661 */
662 <T extends JCTree> void attribStats(List<T> trees, Env<AttrContext> env) {
663 for (List<T> l = trees; l.nonEmpty(); l = l.tail)
664 attribStat(l.head, env);
665 }
666
667 /** Attribute the arguments in a method call, returning a list of types.
668 */
669 List<Type> attribArgs(List<JCExpression> trees, Env<AttrContext> env) {
670 ListBuffer<Type> argtypes = new ListBuffer<Type>();
671 for (JCExpression arg : trees) {
672 Type argtype = allowPoly && deferredAttr.isDeferred(env, arg) ?
673 deferredAttr.new DeferredType(arg, env) :
674 chk.checkNonVoid(arg, attribExpr(arg, env, Infer.anyPoly));
675 argtypes.append(argtype);
676 }
677 return argtypes.toList();
678 }
679
680 /** Attribute a type argument list, returning a list of types.
681 * Caller is responsible for calling checkRefTypes.
682 */
683 List<Type> attribAnyTypes(List<JCExpression> trees, Env<AttrContext> env) {
684 ListBuffer<Type> argtypes = new ListBuffer<Type>();
685 for (List<JCExpression> l = trees; l.nonEmpty(); l = l.tail)
686 argtypes.append(attribType(l.head, env));
687 return argtypes.toList();
688 }
689
690 /** Attribute a type argument list, returning a list of types.
691 * Check that all the types are references.
692 */
693 List<Type> attribTypes(List<JCExpression> trees, Env<AttrContext> env) {
694 List<Type> types = attribAnyTypes(trees, env);
695 return chk.checkRefTypes(trees, types);
696 }
697
698 /**
699 * Attribute type variables (of generic classes or methods).
700 * Compound types are attributed later in attribBounds.
701 * @param typarams the type variables to enter
702 * @param env the current environment
703 */
704 void attribTypeVariables(List<JCTypeParameter> typarams, Env<AttrContext> env) {
705 for (JCTypeParameter tvar : typarams) {
706 TypeVar a = (TypeVar)tvar.type;
707 a.tsym.flags_field |= UNATTRIBUTED;
708 a.bound = Type.noType;
709 if (!tvar.bounds.isEmpty()) {
710 List<Type> bounds = List.of(attribType(tvar.bounds.head, env));
711 for (JCExpression bound : tvar.bounds.tail)
712 bounds = bounds.prepend(attribType(bound, env));
713 types.setBounds(a, bounds.reverse());
714 } else {
715 // if no bounds are given, assume a single bound of
716 // java.lang.Object.
717 types.setBounds(a, List.of(syms.objectType));
718 }
719 a.tsym.flags_field &= ~UNATTRIBUTED;
720 }
721 for (JCTypeParameter tvar : typarams) {
722 chk.checkNonCyclic(tvar.pos(), (TypeVar)tvar.type);
723 }
724 }
725
726 /**
727 * Attribute the type references in a list of annotations.
728 */
729 void attribAnnotationTypes(List<JCAnnotation> annotations,
730 Env<AttrContext> env) {
731 for (List<JCAnnotation> al = annotations; al.nonEmpty(); al = al.tail) {
732 JCAnnotation a = al.head;
733 attribType(a.annotationType, env);
734 }
735 }
736
737 /**
738 * Attribute a "lazy constant value".
739 * @param env The env for the const value
740 * @param initializer The initializer for the const value
741 * @param type The expected type, or null
742 * @see VarSymbol#setLazyConstValue
743 */
744 public Object attribLazyConstantValue(Env<AttrContext> env,
745 JCTree.JCExpression initializer,
746 Type type) {
747
748 // in case no lint value has been set up for this env, scan up
749 // env stack looking for smallest enclosing env for which it is set.
750 Env<AttrContext> lintEnv = env;
751 while (lintEnv.info.lint == null)
752 lintEnv = lintEnv.next;
753
754 // Having found the enclosing lint value, we can initialize the lint value for this class
755 // ... but ...
756 // There's a problem with evaluating annotations in the right order, such that
757 // env.info.enclVar.attributes_field might not yet have been evaluated, and so might be
758 // null. In that case, calling augment will throw an NPE. To avoid this, for now we
759 // revert to the jdk 6 behavior and ignore the (unevaluated) attributes.
760 if (env.info.enclVar.annotations.pendingCompletion()) {
761 env.info.lint = lintEnv.info.lint;
762 } else {
763 env.info.lint = lintEnv.info.lint.augment(env.info.enclVar.annotations,
764 env.info.enclVar.flags());
765 }
766
767 Lint prevLint = chk.setLint(env.info.lint);
768 JavaFileObject prevSource = log.useSource(env.toplevel.sourcefile);
769
770 try {
771 // Use null as symbol to not attach the type annotation to any symbol.
772 // The initializer will later also be visited and then we'll attach
773 // to the symbol.
774 // This prevents having multiple type annotations, just because of
775 // lazy constant value evaluation.
776 memberEnter.typeAnnotate(initializer, env, null);
777 annotate.flush();
778 Type itype = attribExpr(initializer, env, type);
779 if (itype.constValue() != null)
780 return coerce(itype, type).constValue();
781 else
782 return null;
783 } finally {
784 env.info.lint = prevLint;
785 log.useSource(prevSource);
786 }
787 }
788
789 /** Attribute type reference in an `extends' or `implements' clause.
790 * Supertypes of anonymous inner classes are usually already attributed.
791 *
792 * @param tree The tree making up the type reference.
793 * @param env The environment current at the reference.
794 * @param classExpected true if only a class is expected here.
795 * @param interfaceExpected true if only an interface is expected here.
796 */
797 Type attribBase(JCTree tree,
798 Env<AttrContext> env,
799 boolean classExpected,
800 boolean interfaceExpected,
801 boolean checkExtensible) {
802 Type t = tree.type != null ?
803 tree.type :
804 attribType(tree, env);
805 return checkBase(t, tree, env, classExpected, interfaceExpected, checkExtensible);
806 }
807 Type checkBase(Type t,
808 JCTree tree,
809 Env<AttrContext> env,
810 boolean classExpected,
811 boolean interfaceExpected,
812 boolean checkExtensible) {
813 if (t.isErroneous())
814 return t;
815 if (t.hasTag(TYPEVAR) && !classExpected && !interfaceExpected) {
816 // check that type variable is already visible
817 if (t.getUpperBound() == null) {
818 log.error(tree.pos(), "illegal.forward.ref");
819 return types.createErrorType(t);
820 }
821 } else {
822 t = chk.checkClassType(tree.pos(), t, checkExtensible|!allowGenerics);
823 }
824 if (interfaceExpected && (t.tsym.flags() & INTERFACE) == 0) {
825 log.error(tree.pos(), "intf.expected.here");
826 // return errType is necessary since otherwise there might
827 // be undetected cycles which cause attribution to loop
828 return types.createErrorType(t);
829 } else if (checkExtensible &&
830 classExpected &&
831 (t.tsym.flags() & INTERFACE) != 0) {
832 log.error(tree.pos(), "no.intf.expected.here");
833 return types.createErrorType(t);
834 }
835 if (checkExtensible &&
836 ((t.tsym.flags() & FINAL) != 0)) {
837 log.error(tree.pos(),
838 "cant.inherit.from.final", t.tsym);
839 }
840 chk.checkNonCyclic(tree.pos(), t);
841 return t;
842 }
843
844 Type attribIdentAsEnumType(Env<AttrContext> env, JCIdent id) {
845 Assert.check((env.enclClass.sym.flags() & ENUM) != 0);
846 id.type = env.info.scope.owner.type;
847 id.sym = env.info.scope.owner;
848 return id.type;
849 }
850
851 public void visitClassDef(JCClassDecl tree) {
852 // Local classes have not been entered yet, so we need to do it now:
853 if ((env.info.scope.owner.kind & (VAR | MTH)) != 0)
854 enter.classEnter(tree, env);
855
856 ClassSymbol c = tree.sym;
857 if (c == null) {
858 // exit in case something drastic went wrong during enter.
859 result = null;
860 } else {
861 // make sure class has been completed:
862 c.complete();
863
864 // If this class appears as an anonymous class
865 // in a superclass constructor call where
866 // no explicit outer instance is given,
867 // disable implicit outer instance from being passed.
868 // (This would be an illegal access to "this before super").
869 if (env.info.isSelfCall &&
870 env.tree.hasTag(NEWCLASS) &&
871 ((JCNewClass) env.tree).encl == null)
872 {
873 c.flags_field |= NOOUTERTHIS;
874 }
875 attribClass(tree.pos(), c);
876 result = tree.type = c.type;
877 }
878 }
879
880 public void visitMethodDef(JCMethodDecl tree) {
881 MethodSymbol m = tree.sym;
882 boolean isDefaultMethod = (m.flags() & DEFAULT) != 0;
883
884 Lint lint = env.info.lint.augment(m.annotations, m.flags());
885 Lint prevLint = chk.setLint(lint);
886 MethodSymbol prevMethod = chk.setMethod(m);
887 try {
888 deferredLintHandler.flush(tree.pos());
889 chk.checkDeprecatedAnnotation(tree.pos(), m);
890
891
892 // Create a new environment with local scope
893 // for attributing the method.
894 Env<AttrContext> localEnv = memberEnter.methodEnv(tree, env);
895 localEnv.info.lint = lint;
896
897 attribStats(tree.typarams, localEnv);
898
899 // If we override any other methods, check that we do so properly.
900 // JLS ???
901 if (m.isStatic()) {
902 chk.checkHideClashes(tree.pos(), env.enclClass.type, m);
903 } else {
904 chk.checkOverrideClashes(tree.pos(), env.enclClass.type, m);
905 }
906 chk.checkOverride(tree, m);
907
908 if (isDefaultMethod && types.overridesObjectMethod(m.enclClass(), m)) {
909 log.error(tree, "default.overrides.object.member", m.name, Kinds.kindName(m.location()), m.location());
910 }
911
912 // Enter all type parameters into the local method scope.
913 for (List<JCTypeParameter> l = tree.typarams; l.nonEmpty(); l = l.tail)
914 localEnv.info.scope.enterIfAbsent(l.head.type.tsym);
915
916 ClassSymbol owner = env.enclClass.sym;
917 if ((owner.flags() & ANNOTATION) != 0 &&
918 tree.params.nonEmpty())
919 log.error(tree.params.head.pos(),
920 "intf.annotation.members.cant.have.params");
921
922 // Attribute all value parameters.
923 for (List<JCVariableDecl> l = tree.params; l.nonEmpty(); l = l.tail) {
924 attribStat(l.head, localEnv);
925 }
926
927 chk.checkVarargsMethodDecl(localEnv, tree);
928
929 // Check that type parameters are well-formed.
930 chk.validate(tree.typarams, localEnv);
931
932 // Check that result type is well-formed.
933 chk.validate(tree.restype, localEnv);
934
935 // Check that receiver type is well-formed.
936 if (tree.recvparam != null) {
937 // Use a new environment to check the receiver parameter.
938 // Otherwise I get "might not have been initialized" errors.
939 // Is there a better way?
940 Env<AttrContext> newEnv = memberEnter.methodEnv(tree, env);
941 attribType(tree.recvparam, newEnv);
942 chk.validate(tree.recvparam, newEnv);
943 }
944
945 // annotation method checks
946 if ((owner.flags() & ANNOTATION) != 0) {
947 // annotation method cannot have throws clause
948 if (tree.thrown.nonEmpty()) {
949 log.error(tree.thrown.head.pos(),
950 "throws.not.allowed.in.intf.annotation");
951 }
952 // annotation method cannot declare type-parameters
953 if (tree.typarams.nonEmpty()) {
954 log.error(tree.typarams.head.pos(),
955 "intf.annotation.members.cant.have.type.params");
956 }
957 // validate annotation method's return type (could be an annotation type)
958 chk.validateAnnotationType(tree.restype);
959 // ensure that annotation method does not clash with members of Object/Annotation
960 chk.validateAnnotationMethod(tree.pos(), m);
961
962 if (tree.defaultValue != null) {
963 // if default value is an annotation, check it is a well-formed
964 // annotation value (e.g. no duplicate values, no missing values, etc.)
965 chk.validateAnnotationTree(tree.defaultValue);
966 }
967 }
968
969 for (List<JCExpression> l = tree.thrown; l.nonEmpty(); l = l.tail)
970 chk.checkType(l.head.pos(), l.head.type, syms.throwableType);
971
972 if (tree.body == null) {
973 // Empty bodies are only allowed for
974 // abstract, native, or interface methods, or for methods
975 // in a retrofit signature class.
976 if (isDefaultMethod || (tree.sym.flags() & (ABSTRACT | NATIVE)) == 0 &&
977 !relax)
978 log.error(tree.pos(), "missing.meth.body.or.decl.abstract");
979 if (tree.defaultValue != null) {
980 if ((owner.flags() & ANNOTATION) == 0)
981 log.error(tree.pos(),
982 "default.allowed.in.intf.annotation.member");
983 }
984 } else if ((tree.sym.flags() & ABSTRACT) != 0 && !isDefaultMethod) {
985 if ((owner.flags() & INTERFACE) != 0) {
986 log.error(tree.body.pos(), "intf.meth.cant.have.body");
987 } else {
988 log.error(tree.pos(), "abstract.meth.cant.have.body");
989 }
990 } else if ((tree.mods.flags & NATIVE) != 0) {
991 log.error(tree.pos(), "native.meth.cant.have.body");
992 } else {
993 // Add an implicit super() call unless an explicit call to
994 // super(...) or this(...) is given
995 // or we are compiling class java.lang.Object.
996 if (tree.name == names.init && owner.type != syms.objectType) {
997 JCBlock body = tree.body;
998 if (body.stats.isEmpty() ||
999 !TreeInfo.isSelfCall(body.stats.head)) {
1000 body.stats = body.stats.
1001 prepend(memberEnter.SuperCall(make.at(body.pos),
1002 List.<Type>nil(),
1003 List.<JCVariableDecl>nil(),
1004 false));
1005 } else if ((env.enclClass.sym.flags() & ENUM) != 0 &&
1006 (tree.mods.flags & GENERATEDCONSTR) == 0 &&
1007 TreeInfo.isSuperCall(body.stats.head)) {
1008 // enum constructors are not allowed to call super
1009 // directly, so make sure there aren't any super calls
1010 // in enum constructors, except in the compiler
1011 // generated one.
1012 log.error(tree.body.stats.head.pos(),
1013 "call.to.super.not.allowed.in.enum.ctor",
1014 env.enclClass.sym);
1015 }
1016 }
1017
1018 // Attribute all type annotations in the body
1019 memberEnter.typeAnnotate(tree.body, localEnv, m);
1020 annotate.flush();
1021
1022 // Attribute method body.
1023 attribStat(tree.body, localEnv);
1024 }
1025
1026 localEnv.info.scope.leave();
1027 result = tree.type = m.type;
1028 chk.validateAnnotations(tree.mods.annotations, m);
1029 }
1030 finally {
1031 chk.setLint(prevLint);
1032 chk.setMethod(prevMethod);
1033 }
1034 }
1035
1036 public void visitVarDef(JCVariableDecl tree) {
1037 // Local variables have not been entered yet, so we need to do it now:
1038 if (env.info.scope.owner.kind == MTH) {
1039 if (tree.sym != null) {
1040 // parameters have already been entered
1041 env.info.scope.enter(tree.sym);
1042 } else {
1043 memberEnter.memberEnter(tree, env);
1044 annotate.flush();
1045 }
1046 } else {
1047 if (tree.init != null) {
1048 // Field initializer expression need to be entered.
1049 memberEnter.typeAnnotate(tree.init, env, tree.sym);
1050 annotate.flush();
1051 }
1052 }
1053
1054 VarSymbol v = tree.sym;
1055 Lint lint = env.info.lint.augment(v.annotations, v.flags());
1056 Lint prevLint = chk.setLint(lint);
1057
1058 // Check that the variable's declared type is well-formed.
1059 boolean isImplicitLambdaParameter = env.tree.hasTag(LAMBDA) &&
1060 ((JCLambda)env.tree).paramKind == JCLambda.ParameterKind.IMPLICIT &&
1061 (tree.sym.flags() & PARAMETER) != 0;
1062 chk.validate(tree.vartype, env, !isImplicitLambdaParameter);
1063 deferredLintHandler.flush(tree.pos());
1064
1065 try {
1066 chk.checkDeprecatedAnnotation(tree.pos(), v);
1067
1068 if (tree.init != null) {
1069 if ((v.flags_field & FINAL) != 0 &&
1070 !tree.init.hasTag(NEWCLASS) &&
1071 !tree.init.hasTag(LAMBDA) &&
1072 !tree.init.hasTag(REFERENCE)) {
1073 // In this case, `v' is final. Ensure that it's initializer is
1074 // evaluated.
1075 v.getConstValue(); // ensure initializer is evaluated
1076 } else {
1077 // Attribute initializer in a new environment
1078 // with the declared variable as owner.
1079 // Check that initializer conforms to variable's declared type.
1080 Env<AttrContext> initEnv = memberEnter.initEnv(tree, env);
1081 initEnv.info.lint = lint;
1082 // In order to catch self-references, we set the variable's
1083 // declaration position to maximal possible value, effectively
1084 // marking the variable as undefined.
1085 initEnv.info.enclVar = v;
1086 attribExpr(tree.init, initEnv, v.type);
1087 }
1088 }
1089 result = tree.type = v.type;
1090 chk.validateAnnotations(tree.mods.annotations, v);
1091 }
1092 finally {
1093 chk.setLint(prevLint);
1094 }
1095 }
1096
1097 public void visitSkip(JCSkip tree) {
1098 result = null;
1099 }
1100
1101 public void visitBlock(JCBlock tree) {
1102 if (env.info.scope.owner.kind == TYP) {
1103 // Block is a static or instance initializer;
1104 // let the owner of the environment be a freshly
1105 // created BLOCK-method.
1106 Env<AttrContext> localEnv =
1107 env.dup(tree, env.info.dup(env.info.scope.dupUnshared()));
1108 localEnv.info.scope.owner =
1109 new MethodSymbol(tree.flags | BLOCK |
1110 env.info.scope.owner.flags() & STRICTFP, names.empty, null,
1111 env.info.scope.owner);
1112 if ((tree.flags & STATIC) != 0) localEnv.info.staticLevel++;
1113
1114 // Attribute all type annotations in the block
1115 memberEnter.typeAnnotate(tree, localEnv, localEnv.info.scope.owner);
1116 annotate.flush();
1117
1118 {
1119 // Store init and clinit type annotations with the ClassSymbol
1120 // to allow output in Gen.normalizeDefs.
1121 ClassSymbol cs = (ClassSymbol)env.info.scope.owner;
1122 List<Attribute.TypeCompound> tas = localEnv.info.scope.owner.getRawTypeAttributes();
1123 if ((tree.flags & STATIC) != 0) {
1124 cs.annotations.appendClassInitTypeAttributes(tas);
1125 } else {
1126 cs.annotations.appendInitTypeAttributes(tas);
1127 }
1128 }
1129
1130 attribStats(tree.stats, localEnv);
1131 } else {
1132 // Create a new local environment with a local scope.
1133 Env<AttrContext> localEnv =
1134 env.dup(tree, env.info.dup(env.info.scope.dup()));
1135 try {
1136 attribStats(tree.stats, localEnv);
1137 } finally {
1138 localEnv.info.scope.leave();
1139 }
1140 }
1141 result = null;
1142 }
1143
1144 public void visitDoLoop(JCDoWhileLoop tree) {
1145 attribStat(tree.body, env.dup(tree));
1146 attribExpr(tree.cond, env, syms.booleanType);
1147 result = null;
1148 }
1149
1150 public void visitWhileLoop(JCWhileLoop tree) {
1151 attribExpr(tree.cond, env, syms.booleanType);
1152 attribStat(tree.body, env.dup(tree));
1153 result = null;
1154 }
1155
1156 public void visitForLoop(JCForLoop tree) {
1157 Env<AttrContext> loopEnv =
1158 env.dup(env.tree, env.info.dup(env.info.scope.dup()));
1159 try {
1160 attribStats(tree.init, loopEnv);
1161 if (tree.cond != null) attribExpr(tree.cond, loopEnv, syms.booleanType);
1162 loopEnv.tree = tree; // before, we were not in loop!
1163 attribStats(tree.step, loopEnv);
1164 attribStat(tree.body, loopEnv);
1165 result = null;
1166 }
1167 finally {
1168 loopEnv.info.scope.leave();
1169 }
1170 }
1171
1172 public void visitForeachLoop(JCEnhancedForLoop tree) {
1173 Env<AttrContext> loopEnv =
1174 env.dup(env.tree, env.info.dup(env.info.scope.dup()));
1175 try {
1176 attribStat(tree.var, loopEnv);
1177 Type exprType = types.upperBound(attribExpr(tree.expr, loopEnv));
1178 chk.checkNonVoid(tree.pos(), exprType);
1179 Type elemtype = types.elemtype(exprType); // perhaps expr is an array?
1180 if (elemtype == null) {
1181 // or perhaps expr implements Iterable<T>?
1182 Type base = types.asSuper(exprType, syms.iterableType.tsym);
1183 if (base == null) {
1184 log.error(tree.expr.pos(),
1185 "foreach.not.applicable.to.type",
1186 exprType,
1187 diags.fragment("type.req.array.or.iterable"));
1188 elemtype = types.createErrorType(exprType);
1189 } else {
1190 List<Type> iterableParams = base.allparams();
1191 elemtype = iterableParams.isEmpty()
1192 ? syms.objectType
1193 : types.upperBound(iterableParams.head);
1194 }
1195 }
1196 chk.checkType(tree.expr.pos(), elemtype, tree.var.sym.type);
1197 loopEnv.tree = tree; // before, we were not in loop!
1198 attribStat(tree.body, loopEnv);
1199 result = null;
1200 }
1201 finally {
1202 loopEnv.info.scope.leave();
1203 }
1204 }
1205
1206 public void visitLabelled(JCLabeledStatement tree) {
1207 // Check that label is not used in an enclosing statement
1208 Env<AttrContext> env1 = env;
1209 while (env1 != null && !env1.tree.hasTag(CLASSDEF)) {
1210 if (env1.tree.hasTag(LABELLED) &&
1211 ((JCLabeledStatement) env1.tree).label == tree.label) {
1212 log.error(tree.pos(), "label.already.in.use",
1213 tree.label);
1214 break;
1215 }
1216 env1 = env1.next;
1217 }
1218
1219 attribStat(tree.body, env.dup(tree));
1220 result = null;
1221 }
1222
1223 public void visitSwitch(JCSwitch tree) {
1224 Type seltype = attribExpr(tree.selector, env);
1225
1226 Env<AttrContext> switchEnv =
1227 env.dup(tree, env.info.dup(env.info.scope.dup()));
1228
1229 try {
1230
1231 boolean enumSwitch =
1232 allowEnums &&
1233 (seltype.tsym.flags() & Flags.ENUM) != 0;
1234 boolean stringSwitch = false;
1235 if (types.isSameType(seltype, syms.stringType)) {
1236 if (allowStringsInSwitch) {
1237 stringSwitch = true;
1238 } else {
1239 log.error(tree.selector.pos(), "string.switch.not.supported.in.source", sourceName);
1240 }
1241 }
1242 if (!enumSwitch && !stringSwitch)
1243 seltype = chk.checkType(tree.selector.pos(), seltype, syms.intType);
1244
1245 // Attribute all cases and
1246 // check that there are no duplicate case labels or default clauses.
1247 Set<Object> labels = new HashSet<Object>(); // The set of case labels.
1248 boolean hasDefault = false; // Is there a default label?
1249 for (List<JCCase> l = tree.cases; l.nonEmpty(); l = l.tail) {
1250 JCCase c = l.head;
1251 Env<AttrContext> caseEnv =
1252 switchEnv.dup(c, env.info.dup(switchEnv.info.scope.dup()));
1253 try {
1254 if (c.pat != null) {
1255 if (enumSwitch) {
1256 Symbol sym = enumConstant(c.pat, seltype);
1257 if (sym == null) {
1258 log.error(c.pat.pos(), "enum.label.must.be.unqualified.enum");
1259 } else if (!labels.add(sym)) {
1260 log.error(c.pos(), "duplicate.case.label");
1261 }
1262 } else {
1263 Type pattype = attribExpr(c.pat, switchEnv, seltype);
1264 if (!pattype.hasTag(ERROR)) {
1265 if (pattype.constValue() == null) {
1266 log.error(c.pat.pos(),
1267 (stringSwitch ? "string.const.req" : "const.expr.req"));
1268 } else if (labels.contains(pattype.constValue())) {
1269 log.error(c.pos(), "duplicate.case.label");
1270 } else {
1271 labels.add(pattype.constValue());
1272 }
1273 }
1274 }
1275 } else if (hasDefault) {
1276 log.error(c.pos(), "duplicate.default.label");
1277 } else {
1278 hasDefault = true;
1279 }
1280 attribStats(c.stats, caseEnv);
1281 } finally {
1282 caseEnv.info.scope.leave();
1283 addVars(c.stats, switchEnv.info.scope);
1284 }
1285 }
1286
1287 result = null;
1288 }
1289 finally {
1290 switchEnv.info.scope.leave();
1291 }
1292 }
1293 // where
1294 /** Add any variables defined in stats to the switch scope. */
1295 private static void addVars(List<JCStatement> stats, Scope switchScope) {
1296 for (;stats.nonEmpty(); stats = stats.tail) {
1297 JCTree stat = stats.head;
1298 if (stat.hasTag(VARDEF))
1299 switchScope.enter(((JCVariableDecl) stat).sym);
1300 }
1301 }
1302 // where
1303 /** Return the selected enumeration constant symbol, or null. */
1304 private Symbol enumConstant(JCTree tree, Type enumType) {
1305 if (!tree.hasTag(IDENT)) {
1306 log.error(tree.pos(), "enum.label.must.be.unqualified.enum");
1307 return syms.errSymbol;
1308 }
1309 JCIdent ident = (JCIdent)tree;
1310 Name name = ident.name;
1311 for (Scope.Entry e = enumType.tsym.members().lookup(name);
1312 e.scope != null; e = e.next()) {
1313 if (e.sym.kind == VAR) {
1314 Symbol s = ident.sym = e.sym;
1315 ((VarSymbol)s).getConstValue(); // ensure initializer is evaluated
1316 ident.type = s.type;
1317 return ((s.flags_field & Flags.ENUM) == 0)
1318 ? null : s;
1319 }
1320 }
1321 return null;
1322 }
1323
1324 public void visitSynchronized(JCSynchronized tree) {
1325 chk.checkRefType(tree.pos(), attribExpr(tree.lock, env));
1326 attribStat(tree.body, env);
1327 result = null;
1328 }
1329
1330 public void visitTry(JCTry tree) {
1331 // Create a new local environment with a local
1332 Env<AttrContext> localEnv = env.dup(tree, env.info.dup(env.info.scope.dup()));
1333 try {
1334 boolean isTryWithResource = tree.resources.nonEmpty();
1335 // Create a nested environment for attributing the try block if needed
1336 Env<AttrContext> tryEnv = isTryWithResource ?
1337 env.dup(tree, localEnv.info.dup(localEnv.info.scope.dup())) :
1338 localEnv;
1339 try {
1340 // Attribute resource declarations
1341 for (JCTree resource : tree.resources) {
1342 CheckContext twrContext = new Check.NestedCheckContext(resultInfo.checkContext) {
1343 @Override
1344 public void report(DiagnosticPosition pos, JCDiagnostic details) {
1345 chk.basicHandler.report(pos, diags.fragment("try.not.applicable.to.type", details));
1346 }
1347 };
1348 ResultInfo twrResult = new ResultInfo(VAL, syms.autoCloseableType, twrContext);
1349 if (resource.hasTag(VARDEF)) {
1350 attribStat(resource, tryEnv);
1351 twrResult.check(resource, resource.type);
1352
1353 //check that resource type cannot throw InterruptedException
1354 checkAutoCloseable(resource.pos(), localEnv, resource.type);
1355
1356 VarSymbol var = ((JCVariableDecl) resource).sym;
1357 var.setData(ElementKind.RESOURCE_VARIABLE);
1358 } else {
1359 attribTree(resource, tryEnv, twrResult);
1360 }
1361 }
1362 // Attribute body
1363 attribStat(tree.body, tryEnv);
1364 } finally {
1365 if (isTryWithResource)
1366 tryEnv.info.scope.leave();
1367 }
1368
1369 // Attribute catch clauses
1370 for (List<JCCatch> l = tree.catchers; l.nonEmpty(); l = l.tail) {
1371 JCCatch c = l.head;
1372 Env<AttrContext> catchEnv =
1373 localEnv.dup(c, localEnv.info.dup(localEnv.info.scope.dup()));
1374 try {
1375 Type ctype = attribStat(c.param, catchEnv);
1376 if (TreeInfo.isMultiCatch(c)) {
1377 //multi-catch parameter is implicitly marked as final
1378 c.param.sym.flags_field |= FINAL | UNION;
1379 }
1380 if (c.param.sym.kind == Kinds.VAR) {
1381 c.param.sym.setData(ElementKind.EXCEPTION_PARAMETER);
1382 }
1383 chk.checkType(c.param.vartype.pos(),
1384 chk.checkClassType(c.param.vartype.pos(), ctype),
1385 syms.throwableType);
1386 attribStat(c.body, catchEnv);
1387 } finally {
1388 catchEnv.info.scope.leave();
1389 }
1390 }
1391
1392 // Attribute finalizer
1393 if (tree.finalizer != null) attribStat(tree.finalizer, localEnv);
1394 result = null;
1395 }
1396 finally {
1397 localEnv.info.scope.leave();
1398 }
1399 }
1400
1401 void checkAutoCloseable(DiagnosticPosition pos, Env<AttrContext> env, Type resource) {
1402 if (!resource.isErroneous() &&
1403 types.asSuper(resource, syms.autoCloseableType.tsym) != null &&
1404 !types.isSameType(resource, syms.autoCloseableType)) { // Don't emit warning for AutoCloseable itself
1405 Symbol close = syms.noSymbol;
1406 Log.DiagnosticHandler discardHandler = new Log.DiscardDiagnosticHandler(log);
1407 try {
1408 close = rs.resolveQualifiedMethod(pos,
1409 env,
1410 resource,
1411 names.close,
1412 List.<Type>nil(),
1413 List.<Type>nil());
1414 }
1415 finally {
1416 log.popDiagnosticHandler(discardHandler);
1417 }
1418 if (close.kind == MTH &&
1419 close.overrides(syms.autoCloseableClose, resource.tsym, types, true) &&
1420 chk.isHandled(syms.interruptedExceptionType, types.memberType(resource, close).getThrownTypes()) &&
1421 env.info.lint.isEnabled(LintCategory.TRY)) {
1422 log.warning(LintCategory.TRY, pos, "try.resource.throws.interrupted.exc", resource);
1423 }
1424 }
1425 }
1426
1427 public void visitConditional(JCConditional tree) {
1428 Type condtype = attribExpr(tree.cond, env, syms.booleanType);
1429
1430 tree.polyKind = (!allowPoly ||
1431 pt().hasTag(NONE) && pt() != Type.recoveryType ||
1432 isBooleanOrNumeric(env, tree)) ?
1433 PolyKind.STANDALONE : PolyKind.POLY;
1434
1435 if (tree.polyKind == PolyKind.POLY && resultInfo.pt.hasTag(VOID)) {
1436 //cannot get here (i.e. it means we are returning from void method - which is already an error)
1437 resultInfo.checkContext.report(tree, diags.fragment("conditional.target.cant.be.void"));
1438 result = tree.type = types.createErrorType(resultInfo.pt);
1439 return;
1440 }
1441
1442 ResultInfo condInfo = tree.polyKind == PolyKind.STANDALONE ?
1443 unknownExprInfo :
1444 resultInfo.dup(new Check.NestedCheckContext(resultInfo.checkContext) {
1445 //this will use enclosing check context to check compatibility of
1446 //subexpression against target type; if we are in a method check context,
1447 //depending on whether boxing is allowed, we could have incompatibilities
1448 @Override
1449 public void report(DiagnosticPosition pos, JCDiagnostic details) {
1450 enclosingContext.report(pos, diags.fragment("incompatible.type.in.conditional", details));
1451 }
1452 });
1453
1454 Type truetype = attribTree(tree.truepart, env, condInfo);
1455 Type falsetype = attribTree(tree.falsepart, env, condInfo);
1456
1457 Type owntype = (tree.polyKind == PolyKind.STANDALONE) ? condType(tree, truetype, falsetype) : pt();
1458 if (condtype.constValue() != null &&
1459 truetype.constValue() != null &&
1460 falsetype.constValue() != null &&
1461 !owntype.hasTag(NONE)) {
1462 //constant folding
1463 owntype = cfolder.coerce(condtype.isTrue() ? truetype : falsetype, owntype);
1464 }
1465 result = check(tree, owntype, VAL, resultInfo);
1466 }
1467 //where
1468 private boolean isBooleanOrNumeric(Env<AttrContext> env, JCExpression tree) {
1469 switch (tree.getTag()) {
1470 case LITERAL: return ((JCLiteral)tree).typetag.isSubRangeOf(DOUBLE) ||
1471 ((JCLiteral)tree).typetag == BOOLEAN ||
1472 ((JCLiteral)tree).typetag == BOT;
1473 case LAMBDA: case REFERENCE: return false;
1474 case PARENS: return isBooleanOrNumeric(env, ((JCParens)tree).expr);
1475 case CONDEXPR:
1476 JCConditional condTree = (JCConditional)tree;
1477 return isBooleanOrNumeric(env, condTree.truepart) &&
1478 isBooleanOrNumeric(env, condTree.falsepart);
1479 case APPLY:
1480 JCMethodInvocation speculativeMethodTree =
1481 (JCMethodInvocation)deferredAttr.attribSpeculative(tree, env, unknownExprInfo);
1482 Type owntype = TreeInfo.symbol(speculativeMethodTree.meth).type.getReturnType();
1483 return types.unboxedTypeOrType(owntype).isPrimitive();
1484 case NEWCLASS:
1485 JCExpression className =
1486 removeClassParams.translate(((JCNewClass)tree).clazz);
1487 JCExpression speculativeNewClassTree =
1488 (JCExpression)deferredAttr.attribSpeculative(className, env, unknownTypeInfo);
1489 return types.unboxedTypeOrType(speculativeNewClassTree.type).isPrimitive();
1490 default:
1491 Type speculativeType = deferredAttr.attribSpeculative(tree, env, unknownExprInfo).type;
1492 speculativeType = types.unboxedTypeOrType(speculativeType);
1493 return speculativeType.isPrimitive();
1494 }
1495 }
1496 //where
1497 TreeTranslator removeClassParams = new TreeTranslator() {
1498 @Override
1499 public void visitTypeApply(JCTypeApply tree) {
1500 result = translate(tree.clazz);
1501 }
1502 };
1503
1504 /** Compute the type of a conditional expression, after
1505 * checking that it exists. See JLS 15.25. Does not take into
1506 * account the special case where condition and both arms
1507 * are constants.
1508 *
1509 * @param pos The source position to be used for error
1510 * diagnostics.
1511 * @param thentype The type of the expression's then-part.
1512 * @param elsetype The type of the expression's else-part.
1513 */
1514 private Type condType(DiagnosticPosition pos,
1515 Type thentype, Type elsetype) {
1516 // If same type, that is the result
1517 if (types.isSameType(thentype, elsetype))
1518 return thentype.baseType();
1519
1520 Type thenUnboxed = (!allowBoxing || thentype.isPrimitive())
1521 ? thentype : types.unboxedType(thentype);
1522 Type elseUnboxed = (!allowBoxing || elsetype.isPrimitive())
1523 ? elsetype : types.unboxedType(elsetype);
1524
1525 // Otherwise, if both arms can be converted to a numeric
1526 // type, return the least numeric type that fits both arms
1527 // (i.e. return larger of the two, or return int if one
1528 // arm is short, the other is char).
1529 if (thenUnboxed.isPrimitive() && elseUnboxed.isPrimitive()) {
1530 // If one arm has an integer subrange type (i.e., byte,
1531 // short, or char), and the other is an integer constant
1532 // that fits into the subrange, return the subrange type.
1533 if (thenUnboxed.getTag().isStrictSubRangeOf(INT) && elseUnboxed.hasTag(INT) &&
1534 types.isAssignable(elseUnboxed, thenUnboxed))
1535 return thenUnboxed.baseType();
1536 if (elseUnboxed.getTag().isStrictSubRangeOf(INT) && thenUnboxed.hasTag(INT) &&
1537 types.isAssignable(thenUnboxed, elseUnboxed))
1538 return elseUnboxed.baseType();
1539
1540 for (TypeTag tag : TypeTag.values()) {
1541 if (tag.ordinal() >= TypeTag.getTypeTagCount()) break;
1542 Type candidate = syms.typeOfTag[tag.ordinal()];
1543 if (candidate != null &&
1544 candidate.isPrimitive() &&
1545 types.isSubtype(thenUnboxed, candidate) &&
1546 types.isSubtype(elseUnboxed, candidate))
1547 return candidate;
1548 }
1549 }
1550
1551 // Those were all the cases that could result in a primitive
1552 if (allowBoxing) {
1553 if (thentype.isPrimitive())
1554 thentype = types.boxedClass(thentype).type;
1555 if (elsetype.isPrimitive())
1556 elsetype = types.boxedClass(elsetype).type;
1557 }
1558
1559 if (types.isSubtype(thentype, elsetype))
1560 return elsetype.baseType();
1561 if (types.isSubtype(elsetype, thentype))
1562 return thentype.baseType();
1563
1564 if (!allowBoxing || thentype.hasTag(VOID) || elsetype.hasTag(VOID)) {
1565 log.error(pos, "neither.conditional.subtype",
1566 thentype, elsetype);
1567 return thentype.baseType();
1568 }
1569
1570 // both are known to be reference types. The result is
1571 // lub(thentype,elsetype). This cannot fail, as it will
1572 // always be possible to infer "Object" if nothing better.
1573 return types.lub(thentype.baseType(), elsetype.baseType());
1574 }
1575
1576 public void visitIf(JCIf tree) {
1577 attribExpr(tree.cond, env, syms.booleanType);
1578 attribStat(tree.thenpart, env);
1579 if (tree.elsepart != null)
1580 attribStat(tree.elsepart, env);
1581 chk.checkEmptyIf(tree);
1582 result = null;
1583 }
1584
1585 public void visitExec(JCExpressionStatement tree) {
1586 //a fresh environment is required for 292 inference to work properly ---
1587 //see Infer.instantiatePolymorphicSignatureInstance()
1588 Env<AttrContext> localEnv = env.dup(tree);
1589 attribExpr(tree.expr, localEnv);
1590 result = null;
1591 }
1592
1593 public void visitBreak(JCBreak tree) {
1594 tree.target = findJumpTarget(tree.pos(), tree.getTag(), tree.label, env);
1595 result = null;
1596 }
1597
1598 public void visitContinue(JCContinue tree) {
1599 tree.target = findJumpTarget(tree.pos(), tree.getTag(), tree.label, env);
1600 result = null;
1601 }
1602 //where
1603 /** Return the target of a break or continue statement, if it exists,
1604 * report an error if not.
1605 * Note: The target of a labelled break or continue is the
1606 * (non-labelled) statement tree referred to by the label,
1607 * not the tree representing the labelled statement itself.
1608 *
1609 * @param pos The position to be used for error diagnostics
1610 * @param tag The tag of the jump statement. This is either
1611 * Tree.BREAK or Tree.CONTINUE.
1612 * @param label The label of the jump statement, or null if no
1613 * label is given.
1614 * @param env The environment current at the jump statement.
1615 */
1616 private JCTree findJumpTarget(DiagnosticPosition pos,
1617 JCTree.Tag tag,
1618 Name label,
1619 Env<AttrContext> env) {
1620 // Search environments outwards from the point of jump.
1621 Env<AttrContext> env1 = env;
1622 LOOP:
1623 while (env1 != null) {
1624 switch (env1.tree.getTag()) {
1625 case LABELLED:
1626 JCLabeledStatement labelled = (JCLabeledStatement)env1.tree;
1627 if (label == labelled.label) {
1628 // If jump is a continue, check that target is a loop.
1629 if (tag == CONTINUE) {
1630 if (!labelled.body.hasTag(DOLOOP) &&
1631 !labelled.body.hasTag(WHILELOOP) &&
1632 !labelled.body.hasTag(FORLOOP) &&
1633 !labelled.body.hasTag(FOREACHLOOP))
1634 log.error(pos, "not.loop.label", label);
1635 // Found labelled statement target, now go inwards
1636 // to next non-labelled tree.
1637 return TreeInfo.referencedStatement(labelled);
1638 } else {
1639 return labelled;
1640 }
1641 }
1642 break;
1643 case DOLOOP:
1644 case WHILELOOP:
1645 case FORLOOP:
1646 case FOREACHLOOP:
1647 if (label == null) return env1.tree;
1648 break;
1649 case SWITCH:
1650 if (label == null && tag == BREAK) return env1.tree;
1651 break;
1652 case LAMBDA:
1653 case METHODDEF:
1654 case CLASSDEF:
1655 break LOOP;
1656 default:
1657 }
1658 env1 = env1.next;
1659 }
1660 if (label != null)
1661 log.error(pos, "undef.label", label);
1662 else if (tag == CONTINUE)
1663 log.error(pos, "cont.outside.loop");
1664 else
1665 log.error(pos, "break.outside.switch.loop");
1666 return null;
1667 }
1668
1669 public void visitReturn(JCReturn tree) {
1670 // Check that there is an enclosing method which is
1671 // nested within than the enclosing class.
1672 if (env.info.returnResult == null) {
1673 log.error(tree.pos(), "ret.outside.meth");
1674 } else {
1675 // Attribute return expression, if it exists, and check that
1676 // it conforms to result type of enclosing method.
1677 if (tree.expr != null) {
1678 if (env.info.returnResult.pt.hasTag(VOID)) {
1679 env.info.returnResult.checkContext.report(tree.expr.pos(),
1680 diags.fragment("unexpected.ret.val"));
1681 }
1682 attribTree(tree.expr, env, env.info.returnResult);
1683 } else if (!env.info.returnResult.pt.hasTag(VOID)) {
1684 env.info.returnResult.checkContext.report(tree.pos(),
1685 diags.fragment("missing.ret.val"));
1686 }
1687 }
1688 result = null;
1689 }
1690
1691 public void visitThrow(JCThrow tree) {
1692 Type owntype = attribExpr(tree.expr, env, allowPoly ? Type.noType : syms.throwableType);
1693 if (allowPoly) {
1694 chk.checkType(tree, owntype, syms.throwableType);
1695 }
1696 result = null;
1697 }
1698
1699 public void visitAssert(JCAssert tree) {
1700 attribExpr(tree.cond, env, syms.booleanType);
1701 if (tree.detail != null) {
1702 chk.checkNonVoid(tree.detail.pos(), attribExpr(tree.detail, env));
1703 }
1704 result = null;
1705 }
1706
1707 /** Visitor method for method invocations.
1708 * NOTE: The method part of an application will have in its type field
1709 * the return type of the method, not the method's type itself!
1710 */
1711 public void visitApply(JCMethodInvocation tree) {
1712 // The local environment of a method application is
1713 // a new environment nested in the current one.
1714 Env<AttrContext> localEnv = env.dup(tree, env.info.dup());
1715
1716 // The types of the actual method arguments.
1717 List<Type> argtypes;
1718
1719 // The types of the actual method type arguments.
1720 List<Type> typeargtypes = null;
1721
1722 Name methName = TreeInfo.name(tree.meth);
1723
1724 boolean isConstructorCall =
1725 methName == names._this || methName == names._super;
1726
1727 if (isConstructorCall) {
1728 // We are seeing a ...this(...) or ...super(...) call.
1729 // Check that this is the first statement in a constructor.
1730 if (checkFirstConstructorStat(tree, env)) {
1731
1732 // Record the fact
1733 // that this is a constructor call (using isSelfCall).
1734 localEnv.info.isSelfCall = true;
1735
1736 // Attribute arguments, yielding list of argument types.
1737 argtypes = attribArgs(tree.args, localEnv);
1738 typeargtypes = attribTypes(tree.typeargs, localEnv);
1739
1740 // Variable `site' points to the class in which the called
1741 // constructor is defined.
1742 Type site = env.enclClass.sym.type;
1743 if (methName == names._super) {
1744 if (site == syms.objectType) {
1745 log.error(tree.meth.pos(), "no.superclass", site);
1746 site = types.createErrorType(syms.objectType);
1747 } else {
1748 site = types.supertype(site);
1749 }
1750 }
1751
1752 if (site.hasTag(CLASS)) {
1753 Type encl = site.getEnclosingType();
1754 while (encl != null && encl.hasTag(TYPEVAR))
1755 encl = encl.getUpperBound();
1756 if (encl.hasTag(CLASS)) {
1757 // we are calling a nested class
1758
1759 if (tree.meth.hasTag(SELECT)) {
1760 JCTree qualifier = ((JCFieldAccess) tree.meth).selected;
1761
1762 // We are seeing a prefixed call, of the form
1763 // <expr>.super(...).
1764 // Check that the prefix expression conforms
1765 // to the outer instance type of the class.
1766 chk.checkRefType(qualifier.pos(),
1767 attribExpr(qualifier, localEnv,
1768 encl));
1769 } else if (methName == names._super) {
1770 // qualifier omitted; check for existence
1771 // of an appropriate implicit qualifier.
1772 rs.resolveImplicitThis(tree.meth.pos(),
1773 localEnv, site, true);
1774 }
1775 } else if (tree.meth.hasTag(SELECT)) {
1776 log.error(tree.meth.pos(), "illegal.qual.not.icls",
1777 site.tsym);
1778 }
1779
1780 // if we're calling a java.lang.Enum constructor,
1781 // prefix the implicit String and int parameters
1782 if (site.tsym == syms.enumSym && allowEnums)
1783 argtypes = argtypes.prepend(syms.intType).prepend(syms.stringType);
1784
1785 // Resolve the called constructor under the assumption
1786 // that we are referring to a superclass instance of the
1787 // current instance (JLS ???).
1788 boolean selectSuperPrev = localEnv.info.selectSuper;
1789 localEnv.info.selectSuper = true;
1790 localEnv.info.pendingResolutionPhase = null;
1791 Symbol sym = rs.resolveConstructor(
1792 tree.meth.pos(), localEnv, site, argtypes, typeargtypes);
1793 localEnv.info.selectSuper = selectSuperPrev;
1794
1795 // Set method symbol to resolved constructor...
1796 TreeInfo.setSymbol(tree.meth, sym);
1797
1798 // ...and check that it is legal in the current context.
1799 // (this will also set the tree's type)
1800 Type mpt = newMethodTemplate(resultInfo.pt, argtypes, typeargtypes);
1801 checkId(tree.meth, site, sym, localEnv, new ResultInfo(MTH, mpt));
1802 }
1803 // Otherwise, `site' is an error type and we do nothing
1804 }
1805 result = tree.type = syms.voidType;
1806 } else {
1807 // Otherwise, we are seeing a regular method call.
1808 // Attribute the arguments, yielding list of argument types, ...
1809 argtypes = attribArgs(tree.args, localEnv);
1810 typeargtypes = attribAnyTypes(tree.typeargs, localEnv);
1811
1812 // ... and attribute the method using as a prototype a methodtype
1813 // whose formal argument types is exactly the list of actual
1814 // arguments (this will also set the method symbol).
1815 Type mpt = newMethodTemplate(resultInfo.pt, argtypes, typeargtypes);
1816 localEnv.info.pendingResolutionPhase = null;
1817 Type mtype = attribTree(tree.meth, localEnv, new ResultInfo(VAL, mpt, resultInfo.checkContext));
1818
1819 // Compute the result type.
1820 Type restype = mtype.getReturnType();
1821 if (restype.hasTag(WILDCARD))
1822 throw new AssertionError(mtype);
1823
1824 Type qualifier = (tree.meth.hasTag(SELECT))
1825 ? ((JCFieldAccess) tree.meth).selected.type
1826 : env.enclClass.sym.type;
1827 restype = adjustMethodReturnType(qualifier, methName, argtypes, restype);
1828
1829 chk.checkRefTypes(tree.typeargs, typeargtypes);
1830
1831 // Check that value of resulting type is admissible in the
1832 // current context. Also, capture the return type
1833 result = check(tree, capture(restype), VAL, resultInfo);
1834
1835 if (localEnv.info.lastResolveVarargs())
1836 Assert.check(result.isErroneous() || tree.varargsElement != null);
1837 }
1838 chk.validate(tree.typeargs, localEnv);
1839 }
1840 //where
1841 Type adjustMethodReturnType(Type qualifierType, Name methodName, List<Type> argtypes, Type restype) {
1842 if (allowCovariantReturns &&
1843 methodName == names.clone &&
1844 types.isArray(qualifierType)) {
1845 // as a special case, array.clone() has a result that is
1846 // the same as static type of the array being cloned
1847 return qualifierType;
1848 } else if (allowGenerics &&
1849 methodName == names.getClass &&
1850 argtypes.isEmpty()) {
1851 // as a special case, x.getClass() has type Class<? extends |X|>
1852 return new ClassType(restype.getEnclosingType(),
1853 List.<Type>of(new WildcardType(types.erasure(qualifierType),
1854 BoundKind.EXTENDS,
1855 syms.boundClass)),
1856 restype.tsym);
1857 } else {
1858 return restype;
1859 }
1860 }
1861
1862 /** Check that given application node appears as first statement
1863 * in a constructor call.
1864 * @param tree The application node
1865 * @param env The environment current at the application.
1866 */
1867 boolean checkFirstConstructorStat(JCMethodInvocation tree, Env<AttrContext> env) {
1868 JCMethodDecl enclMethod = env.enclMethod;
1869 if (enclMethod != null && enclMethod.name == names.init) {
1870 JCBlock body = enclMethod.body;
1871 if (body.stats.head.hasTag(EXEC) &&
1872 ((JCExpressionStatement) body.stats.head).expr == tree)
1873 return true;
1874 }
1875 log.error(tree.pos(),"call.must.be.first.stmt.in.ctor",
1876 TreeInfo.name(tree.meth));
1877 return false;
1878 }
1879
1880 /** Obtain a method type with given argument types.
1881 */
1882 Type newMethodTemplate(Type restype, List<Type> argtypes, List<Type> typeargtypes) {
1883 MethodType mt = new MethodType(argtypes, restype, List.<Type>nil(), syms.methodClass);
1884 return (typeargtypes == null) ? mt : (Type)new ForAll(typeargtypes, mt);
1885 }
1886
1887 public void visitNewClass(final JCNewClass tree) {
1888 Type owntype = types.createErrorType(tree.type);
1889
1890 // The local environment of a class creation is
1891 // a new environment nested in the current one.
1892 Env<AttrContext> localEnv = env.dup(tree, env.info.dup());
1893
1894 // The anonymous inner class definition of the new expression,
1895 // if one is defined by it.
1896 JCClassDecl cdef = tree.def;
1897
1898 // If enclosing class is given, attribute it, and
1899 // complete class name to be fully qualified
1900 JCExpression clazz = tree.clazz; // Class field following new
1901 JCExpression clazzid; // Identifier in class field
1902 JCAnnotatedType annoclazzid; // Annotated type enclosing clazzid
1903 annoclazzid = null;
1904
1905 if (clazz.hasTag(TYPEAPPLY)) {
1906 clazzid = ((JCTypeApply) clazz).clazz;
1907 if (clazzid.hasTag(ANNOTATED_TYPE)) {
1908 annoclazzid = (JCAnnotatedType) clazzid;
1909 clazzid = annoclazzid.underlyingType;
1910 }
1911 } else {
1912 if (clazz.hasTag(ANNOTATED_TYPE)) {
1913 annoclazzid = (JCAnnotatedType) clazz;
1914 clazzid = annoclazzid.underlyingType;
1915 } else {
1916 clazzid = clazz;
1917 }
1918 }
1919
1920 JCExpression clazzid1 = clazzid; // The same in fully qualified form
1921
1922 if (tree.encl != null) {
1923 // We are seeing a qualified new, of the form
1924 // <expr>.new C <...> (...) ...
1925 // In this case, we let clazz stand for the name of the
1926 // allocated class C prefixed with the type of the qualifier
1927 // expression, so that we can
1928 // resolve it with standard techniques later. I.e., if
1929 // <expr> has type T, then <expr>.new C <...> (...)
1930 // yields a clazz T.C.
1931 Type encltype = chk.checkRefType(tree.encl.pos(),
1932 attribExpr(tree.encl, env));
1933 // TODO 308: in <expr>.new C, do we also want to add the type annotations
1934 // from expr to the combined type, or not? Yes, do this.
1935 clazzid1 = make.at(clazz.pos).Select(make.Type(encltype),
1936 ((JCIdent) clazzid).name);
1937
1938 if (clazz.hasTag(ANNOTATED_TYPE)) {
1939 JCAnnotatedType annoType = (JCAnnotatedType) clazz;
1940 List<JCAnnotation> annos = annoType.annotations;
1941
1942 if (annoType.underlyingType.hasTag(TYPEAPPLY)) {
1943 clazzid1 = make.at(tree.pos).
1944 TypeApply(clazzid1,
1945 ((JCTypeApply) clazz).arguments);
1946 }
1947
1948 clazzid1 = make.at(tree.pos).
1949 AnnotatedType(annos, clazzid1);
1950 } else if (clazz.hasTag(TYPEAPPLY)) {
1951 clazzid1 = make.at(tree.pos).
1952 TypeApply(clazzid1,
1953 ((JCTypeApply) clazz).arguments);
1954 }
1955
1956 clazz = clazzid1;
1957 }
1958
1959 // Attribute clazz expression and store
1960 // symbol + type back into the attributed tree.
1961 Type clazztype = TreeInfo.isEnumInit(env.tree) ?
1962 attribIdentAsEnumType(env, (JCIdent)clazz) :
1963 attribType(clazz, env);
1964
1965 clazztype = chk.checkDiamond(tree, clazztype);
1966 chk.validate(clazz, localEnv);
1967 if (tree.encl != null) {
1968 // We have to work in this case to store
1969 // symbol + type back into the attributed tree.
1970 tree.clazz.type = clazztype;
1971 TreeInfo.setSymbol(clazzid, TreeInfo.symbol(clazzid1));
1972 clazzid.type = ((JCIdent) clazzid).sym.type;
1973 if (annoclazzid != null) {
1974 annoclazzid.type = clazzid.type;
1975 }
1976 if (!clazztype.isErroneous()) {
1977 if (cdef != null && clazztype.tsym.isInterface()) {
1978 log.error(tree.encl.pos(), "anon.class.impl.intf.no.qual.for.new");
1979 } else if (clazztype.tsym.isStatic()) {
1980 log.error(tree.encl.pos(), "qualified.new.of.static.class", clazztype.tsym);
1981 }
1982 }
1983 } else if (!clazztype.tsym.isInterface() &&
1984 clazztype.getEnclosingType().hasTag(CLASS)) {
1985 // Check for the existence of an apropos outer instance
1986 rs.resolveImplicitThis(tree.pos(), env, clazztype);
1987 }
1988
1989 // Attribute constructor arguments.
1990 List<Type> argtypes = attribArgs(tree.args, localEnv);
1991 List<Type> typeargtypes = attribTypes(tree.typeargs, localEnv);
1992
1993 // If we have made no mistakes in the class type...
1994 if (clazztype.hasTag(CLASS)) {
1995 // Enums may not be instantiated except implicitly
1996 if (allowEnums &&
1997 (clazztype.tsym.flags_field&Flags.ENUM) != 0 &&
1998 (!env.tree.hasTag(VARDEF) ||
1999 (((JCVariableDecl) env.tree).mods.flags&Flags.ENUM) == 0 ||
2000 ((JCVariableDecl) env.tree).init != tree))
2001 log.error(tree.pos(), "enum.cant.be.instantiated");
2002 // Check that class is not abstract
2003 if (cdef == null &&
2004 (clazztype.tsym.flags() & (ABSTRACT | INTERFACE)) != 0) {
2005 log.error(tree.pos(), "abstract.cant.be.instantiated",
2006 clazztype.tsym);
2007 } else if (cdef != null && clazztype.tsym.isInterface()) {
2008 // Check that no constructor arguments are given to
2009 // anonymous classes implementing an interface
2010 if (!argtypes.isEmpty())
2011 log.error(tree.args.head.pos(), "anon.class.impl.intf.no.args");
2012
2013 if (!typeargtypes.isEmpty())
2014 log.error(tree.typeargs.head.pos(), "anon.class.impl.intf.no.typeargs");
2015
2016 // Error recovery: pretend no arguments were supplied.
2017 argtypes = List.nil();
2018 typeargtypes = List.nil();
2019 } else if (TreeInfo.isDiamond(tree)) {
2020 ClassType site = new ClassType(clazztype.getEnclosingType(),
2021 clazztype.tsym.type.getTypeArguments(),
2022 clazztype.tsym);
2023
2024 Env<AttrContext> diamondEnv = localEnv.dup(tree);
2025 diamondEnv.info.selectSuper = cdef != null;
2026 diamondEnv.info.pendingResolutionPhase = null;
2027
2028 //if the type of the instance creation expression is a class type
2029 //apply method resolution inference (JLS 15.12.2.7). The return type
2030 //of the resolved constructor will be a partially instantiated type
2031 Symbol constructor = rs.resolveDiamond(tree.pos(),
2032 diamondEnv,
2033 site,
2034 argtypes,
2035 typeargtypes);
2036 tree.constructor = constructor.baseSymbol();
2037
2038 final TypeSymbol csym = clazztype.tsym;
2039 ResultInfo diamondResult = new ResultInfo(MTH, newMethodTemplate(resultInfo.pt, argtypes, typeargtypes), new Check.NestedCheckContext(resultInfo.checkContext) {
2040 @Override
2041 public void report(DiagnosticPosition _unused, JCDiagnostic details) {
2042 enclosingContext.report(tree.clazz,
2043 diags.fragment("cant.apply.diamond.1", diags.fragment("diamond", csym), details));
2044 }
2045 });
2046 Type constructorType = tree.constructorType = types.createErrorType(clazztype);
2047 constructorType = checkId(tree, site,
2048 constructor,
2049 diamondEnv,
2050 diamondResult);
2051
2052 tree.clazz.type = types.createErrorType(clazztype);
2053 if (!constructorType.isErroneous()) {
2054 tree.clazz.type = clazztype = constructorType.getReturnType();
2055 tree.constructorType = types.createMethodTypeWithReturn(constructorType, syms.voidType);
2056 }
2057 clazztype = chk.checkClassType(tree.clazz, tree.clazz.type, true);
2058 }
2059
2060 // Resolve the called constructor under the assumption
2061 // that we are referring to a superclass instance of the
2062 // current instance (JLS ???).
2063 else {
2064 //the following code alters some of the fields in the current
2065 //AttrContext - hence, the current context must be dup'ed in
2066 //order to avoid downstream failures
2067 Env<AttrContext> rsEnv = localEnv.dup(tree);
2068 rsEnv.info.selectSuper = cdef != null;
2069 rsEnv.info.pendingResolutionPhase = null;
2070 tree.constructor = rs.resolveConstructor(
2071 tree.pos(), rsEnv, clazztype, argtypes, typeargtypes);
2072 if (cdef == null) { //do not check twice!
2073 tree.constructorType = checkId(tree,
2074 clazztype,
2075 tree.constructor,
2076 rsEnv,
2077 new ResultInfo(MTH, newMethodTemplate(syms.voidType, argtypes, typeargtypes)));
2078 if (rsEnv.info.lastResolveVarargs())
2079 Assert.check(tree.constructorType.isErroneous() || tree.varargsElement != null);
2080 }
2081 findDiamondIfNeeded(localEnv, tree, clazztype);
2082 }
2083
2084 if (cdef != null) {
2085 // We are seeing an anonymous class instance creation.
2086 // In this case, the class instance creation
2087 // expression
2088 //
2089 // E.new <typeargs1>C<typargs2>(args) { ... }
2090 //
2091 // is represented internally as
2092 //
2093 // E . new <typeargs1>C<typargs2>(args) ( class <empty-name> { ... } ) .
2094 //
2095 // This expression is then *transformed* as follows:
2096 //
2097 // (1) add a STATIC flag to the class definition
2098 // if the current environment is static
2099 // (2) add an extends or implements clause
2100 // (3) add a constructor.
2101 //
2102 // For instance, if C is a class, and ET is the type of E,
2103 // the expression
2104 //
2105 // E.new <typeargs1>C<typargs2>(args) { ... }
2106 //
2107 // is translated to (where X is a fresh name and typarams is the
2108 // parameter list of the super constructor):
2109 //
2110 // new <typeargs1>X(<*nullchk*>E, args) where
2111 // X extends C<typargs2> {
2112 // <typarams> X(ET e, args) {
2113 // e.<typeargs1>super(args)
2114 // }
2115 // ...
2116 // }
2117 if (Resolve.isStatic(env)) cdef.mods.flags |= STATIC;
2118
2119 if (clazztype.tsym.isInterface()) {
2120 cdef.implementing = List.of(clazz);
2121 } else {
2122 cdef.extending = clazz;
2123 }
2124
2125 attribStat(cdef, localEnv);
2126
2127 checkLambdaCandidate(tree, cdef.sym, clazztype);
2128
2129 // If an outer instance is given,
2130 // prefix it to the constructor arguments
2131 // and delete it from the new expression
2132 if (tree.encl != null && !clazztype.tsym.isInterface()) {
2133 tree.args = tree.args.prepend(makeNullCheck(tree.encl));
2134 argtypes = argtypes.prepend(tree.encl.type);
2135 tree.encl = null;
2136 }
2137
2138 // Reassign clazztype and recompute constructor.
2139 clazztype = cdef.sym.type;
2140 Symbol sym = tree.constructor = rs.resolveConstructor(
2141 tree.pos(), localEnv, clazztype, argtypes, typeargtypes);
2142 Assert.check(sym.kind < AMBIGUOUS);
2143 tree.constructor = sym;
2144 tree.constructorType = checkId(tree,
2145 clazztype,
2146 tree.constructor,
2147 localEnv,
2148 new ResultInfo(VAL, newMethodTemplate(syms.voidType, argtypes, typeargtypes)));
2149 } else {
2150 if (tree.clazz.hasTag(ANNOTATED_TYPE)) {
2151 checkForDeclarationAnnotations(((JCAnnotatedType) tree.clazz).annotations,
2152 tree.clazz.type.tsym);
2153 }
2154 }
2155
2156 if (tree.constructor != null && tree.constructor.kind == MTH)
2157 owntype = clazztype;
2158 }
2159 result = check(tree, owntype, VAL, resultInfo);
2160 chk.validate(tree.typeargs, localEnv);
2161 }
2162 //where
2163 void findDiamondIfNeeded(Env<AttrContext> env, JCNewClass tree, Type clazztype) {
2164 if (tree.def == null &&
2165 !clazztype.isErroneous() &&
2166 clazztype.getTypeArguments().nonEmpty() &&
2167 findDiamonds) {
2168 JCTypeApply ta = (JCTypeApply)tree.clazz;
2169 List<JCExpression> prevTypeargs = ta.arguments;
2170 try {
2171 //create a 'fake' diamond AST node by removing type-argument trees
2172 ta.arguments = List.nil();
2173 ResultInfo findDiamondResult = new ResultInfo(VAL,
2174 resultInfo.checkContext.inferenceContext().free(resultInfo.pt) ? Type.noType : pt());
2175 Type inferred = deferredAttr.attribSpeculative(tree, env, findDiamondResult).type;
2176 Type polyPt = allowPoly ?
2177 syms.objectType :
2178 clazztype;
2179 if (!inferred.isErroneous() &&
2180 types.isAssignable(inferred, pt().hasTag(NONE) ? polyPt : pt(), types.noWarnings)) {
2181 String key = types.isSameType(clazztype, inferred) ?
2182 "diamond.redundant.args" :
2183 "diamond.redundant.args.1";
2184 log.warning(tree.clazz.pos(), key, clazztype, inferred);
2185 }
2186 } finally {
2187 ta.arguments = prevTypeargs;
2188 }
2189 }
2190 }
2191
2192 private void checkLambdaCandidate(JCNewClass tree, ClassSymbol csym, Type clazztype) {
2193 if (allowLambda &&
2194 identifyLambdaCandidate &&
2195 clazztype.hasTag(CLASS) &&
2196 !pt().hasTag(NONE) &&
2197 types.isFunctionalInterface(clazztype.tsym)) {
2198 Symbol descriptor = types.findDescriptorSymbol(clazztype.tsym);
2199 int count = 0;
2200 boolean found = false;
2201 for (Symbol sym : csym.members().getElements()) {
2202 if ((sym.flags() & SYNTHETIC) != 0 ||
2203 sym.isConstructor()) continue;
2204 count++;
2205 if (sym.kind != MTH ||
2206 !sym.name.equals(descriptor.name)) continue;
2207 Type mtype = types.memberType(clazztype, sym);
2208 if (types.overrideEquivalent(mtype, types.memberType(clazztype, descriptor))) {
2209 found = true;
2210 }
2211 }
2212 if (found && count == 1) {
2213 log.note(tree.def, "potential.lambda.found");
2214 }
2215 }
2216 }
2217
2218 private void checkForDeclarationAnnotations(List<? extends JCAnnotation> annotations,
2219 Symbol sym) {
2220 // Ensure that no declaration annotations are present.
2221 // Note that a tree type might be an AnnotatedType with
2222 // empty annotations, if only declaration annotations were given.
2223 // This method will raise an error for such a type.
2224 for (JCAnnotation ai : annotations) {
2225 if (TypeAnnotations.annotationType(syms, names, ai.attribute, sym) == TypeAnnotations.AnnotationType.DECLARATION) {
2226 log.error(ai.pos(), "annotation.type.not.applicable");
2227 }
2228 }
2229 }
2230
2231
2232 /** Make an attributed null check tree.
2233 */
2234 public JCExpression makeNullCheck(JCExpression arg) {
2235 // optimization: X.this is never null; skip null check
2236 Name name = TreeInfo.name(arg);
2237 if (name == names._this || name == names._super) return arg;
2238
2239 JCTree.Tag optag = NULLCHK;
2240 JCUnary tree = make.at(arg.pos).Unary(optag, arg);
2241 tree.operator = syms.nullcheck;
2242 tree.type = arg.type;
2243 return tree;
2244 }
2245
2246 public void visitNewArray(JCNewArray tree) {
2247 Type owntype = types.createErrorType(tree.type);
2248 Env<AttrContext> localEnv = env.dup(tree);
2249 Type elemtype;
2250 if (tree.elemtype != null) {
2251 elemtype = attribType(tree.elemtype, localEnv);
2252 chk.validate(tree.elemtype, localEnv);
2253 owntype = elemtype;
2254 for (List<JCExpression> l = tree.dims; l.nonEmpty(); l = l.tail) {
2255 attribExpr(l.head, localEnv, syms.intType);
2256 owntype = new ArrayType(owntype, syms.arrayClass);
2257 }
2258 if (tree.elemtype.hasTag(ANNOTATED_TYPE)) {
2259 checkForDeclarationAnnotations(((JCAnnotatedType) tree.elemtype).annotations,
2260 tree.elemtype.type.tsym);
2261 }
2262 } else {
2263 // we are seeing an untyped aggregate { ... }
2264 // this is allowed only if the prototype is an array
2265 if (pt().hasTag(ARRAY)) {
2266 elemtype = types.elemtype(pt());
2267 } else {
2268 if (!pt().hasTag(ERROR)) {
2269 log.error(tree.pos(), "illegal.initializer.for.type",
2270 pt());
2271 }
2272 elemtype = types.createErrorType(pt());
2273 }
2274 }
2275 if (tree.elems != null) {
2276 attribExprs(tree.elems, localEnv, elemtype);
2277 owntype = new ArrayType(elemtype, syms.arrayClass);
2278 }
2279 if (!types.isReifiable(elemtype))
2280 log.error(tree.pos(), "generic.array.creation");
2281 result = check(tree, owntype, VAL, resultInfo);
2282 }
2283
2284 /*
2285 * A lambda expression can only be attributed when a target-type is available.
2286 * In addition, if the target-type is that of a functional interface whose
2287 * descriptor contains inference variables in argument position the lambda expression
2288 * is 'stuck' (see DeferredAttr).
2289 */
2290 @Override
2291 public void visitLambda(final JCLambda that) {
2292 if (pt().isErroneous() || (pt().hasTag(NONE) && pt() != Type.recoveryType)) {
2293 if (pt().hasTag(NONE)) {
2294 //lambda only allowed in assignment or method invocation/cast context
2295 log.error(that.pos(), "unexpected.lambda");
2296 }
2297 result = that.type = types.createErrorType(pt());
2298 return;
2299 }
2300 //create an environment for attribution of the lambda expression
2301 final Env<AttrContext> localEnv = lambdaEnv(that, env);
2302 boolean needsRecovery =
2303 resultInfo.checkContext.deferredAttrContext().mode == DeferredAttr.AttrMode.CHECK;
2304 try {
2305 Type target = pt();
2306 List<Type> explicitParamTypes = null;
2307 if (that.paramKind == JCLambda.ParameterKind.EXPLICIT) {
2308 //attribute lambda parameters
2309 attribStats(that.params, localEnv);
2310 explicitParamTypes = TreeInfo.types(that.params);
2311 target = infer.instantiateFunctionalInterface(that, target, explicitParamTypes, resultInfo.checkContext);
2312 }
2313
2314 Type lambdaType;
2315 if (pt() != Type.recoveryType) {
2316 target = targetChecker.visit(target, that);
2317 lambdaType = types.findDescriptorType(target);
2318 chk.checkFunctionalInterface(that, target);
2319 } else {
2320 target = Type.recoveryType;
2321 lambdaType = fallbackDescriptorType(that);
2322 }
2323
2324 setFunctionalInfo(that, pt(), lambdaType, target, resultInfo.checkContext.inferenceContext());
2325
2326 if (lambdaType.hasTag(FORALL)) {
2327 //lambda expression target desc cannot be a generic method
2328 resultInfo.checkContext.report(that, diags.fragment("invalid.generic.lambda.target",
2329 lambdaType, kindName(target.tsym), target.tsym));
2330 result = that.type = types.createErrorType(pt());
2331 return;
2332 }
2333
2334 if (that.paramKind == JCLambda.ParameterKind.IMPLICIT) {
2335 //add param type info in the AST
2336 List<Type> actuals = lambdaType.getParameterTypes();
2337 List<JCVariableDecl> params = that.params;
2338
2339 boolean arityMismatch = false;
2340
2341 while (params.nonEmpty()) {
2342 if (actuals.isEmpty()) {
2343 //not enough actuals to perform lambda parameter inference
2344 arityMismatch = true;
2345 }
2346 //reset previously set info
2347 Type argType = arityMismatch ?
2348 syms.errType :
2349 actuals.head;
2350 params.head.vartype = make.at(params.head).Type(argType);
2351 params.head.sym = null;
2352 actuals = actuals.isEmpty() ?
2353 actuals :
2354 actuals.tail;
2355 params = params.tail;
2356 }
2357
2358 //attribute lambda parameters
2359 attribStats(that.params, localEnv);
2360
2361 if (arityMismatch) {
2362 resultInfo.checkContext.report(that, diags.fragment("incompatible.arg.types.in.lambda"));
2363 result = that.type = types.createErrorType(target);
2364 return;
2365 }
2366 }
2367
2368 //from this point on, no recovery is needed; if we are in assignment context
2369 //we will be able to attribute the whole lambda body, regardless of errors;
2370 //if we are in a 'check' method context, and the lambda is not compatible
2371 //with the target-type, it will be recovered anyway in Attr.checkId
2372 needsRecovery = false;
2373
2374 FunctionalReturnContext funcContext = that.getBodyKind() == JCLambda.BodyKind.EXPRESSION ?
2375 new ExpressionLambdaReturnContext((JCExpression)that.getBody(), resultInfo.checkContext) :
2376 new FunctionalReturnContext(resultInfo.checkContext);
2377
2378 ResultInfo bodyResultInfo = lambdaType.getReturnType() == Type.recoveryType ?
2379 recoveryInfo :
2380 new ResultInfo(VAL, lambdaType.getReturnType(), funcContext);
2381 localEnv.info.returnResult = bodyResultInfo;
2382
2383 Log.DeferredDiagnosticHandler lambdaDeferredHandler = new Log.DeferredDiagnosticHandler(log);
2384 try {
2385 if (that.getBodyKind() == JCLambda.BodyKind.EXPRESSION) {
2386 attribTree(that.getBody(), localEnv, bodyResultInfo);
2387 } else {
2388 JCBlock body = (JCBlock)that.body;
2389 attribStats(body.stats, localEnv);
2390 }
2391
2392 if (resultInfo.checkContext.deferredAttrContext().mode == AttrMode.SPECULATIVE) {
2393 //check for errors in lambda body
2394 for (JCDiagnostic deferredDiag : lambdaDeferredHandler.getDiagnostics()) {
2395 if (deferredDiag.getKind() == JCDiagnostic.Kind.ERROR) {
2396 resultInfo.checkContext
2397 .report(that, diags.fragment("bad.arg.types.in.lambda", TreeInfo.types(that.params),
2398 deferredDiag)); //hidden diag parameter
2399 //we mark the lambda as erroneous - this is crucial in the recovery step
2400 //as parameter-dependent type error won't be reported in that stage,
2401 //meaning that a lambda will be deemed erroeneous only if there is
2402 //a target-independent error (which will cause method diagnostic
2403 //to be skipped).
2404 result = that.type = types.createErrorType(target);
2405 return;
2406 }
2407 }
2408 }
2409 } finally {
2410 lambdaDeferredHandler.reportDeferredDiagnostics();
2411 log.popDiagnosticHandler(lambdaDeferredHandler);
2412 }
2413
2414 result = check(that, target, VAL, resultInfo);
2415
2416 boolean isSpeculativeRound =
2417 resultInfo.checkContext.deferredAttrContext().mode == DeferredAttr.AttrMode.SPECULATIVE;
2418
2419 postAttr(that);
2420 flow.analyzeLambda(env, that, make, isSpeculativeRound);
2421
2422 checkLambdaCompatible(that, lambdaType, resultInfo.checkContext, isSpeculativeRound);
2423
2424 if (!isSpeculativeRound) {
2425 checkAccessibleTypes(that, localEnv, resultInfo.checkContext.inferenceContext(), lambdaType, target);
2426 }
2427 result = check(that, target, VAL, resultInfo);
2428 } catch (Types.FunctionDescriptorLookupError ex) {
2429 JCDiagnostic cause = ex.getDiagnostic();
2430 resultInfo.checkContext.report(that, cause);
2431 result = that.type = types.createErrorType(pt());
2432 return;
2433 } finally {
2434 localEnv.info.scope.leave();
2435 if (needsRecovery) {
2436 attribTree(that, env, recoveryInfo);
2437 }
2438 }
2439 }
2440 //where
2441 Types.MapVisitor<DiagnosticPosition> targetChecker = new Types.MapVisitor<DiagnosticPosition>() {
2442
2443 @Override
2444 public Type visitClassType(ClassType t, DiagnosticPosition pos) {
2445 return t.isCompound() ?
2446 visitIntersectionClassType((IntersectionClassType)t, pos) : t;
2447 }
2448
2449 public Type visitIntersectionClassType(IntersectionClassType ict, DiagnosticPosition pos) {
2450 Symbol desc = types.findDescriptorSymbol(makeNotionalInterface(ict));
2451 Type target = null;
2452 for (Type bound : ict.getExplicitComponents()) {
2453 TypeSymbol boundSym = bound.tsym;
2454 if (types.isFunctionalInterface(boundSym) &&
2455 types.findDescriptorSymbol(boundSym) == desc) {
2456 target = bound;
2457 } else if (!boundSym.isInterface() || (boundSym.flags() & ANNOTATION) != 0) {
2458 //bound must be an interface
2459 reportIntersectionError(pos, "not.an.intf.component", boundSym);
2460 }
2461 }
2462 return target != null ?
2463 target :
2464 ict.getExplicitComponents().head; //error recovery
2465 }
2466
2467 private TypeSymbol makeNotionalInterface(IntersectionClassType ict) {
2468 ListBuffer<Type> targs = ListBuffer.lb();
2469 ListBuffer<Type> supertypes = ListBuffer.lb();
2470 for (Type i : ict.interfaces_field) {
2471 if (i.isParameterized()) {
2472 targs.appendList(i.tsym.type.allparams());
2473 }
2474 supertypes.append(i.tsym.type);
2475 }
2476 IntersectionClassType notionalIntf =
2477 (IntersectionClassType)types.makeCompoundType(supertypes.toList());
2478 notionalIntf.allparams_field = targs.toList();
2479 notionalIntf.tsym.flags_field |= INTERFACE;
2480 return notionalIntf.tsym;
2481 }
2482
2483 private void reportIntersectionError(DiagnosticPosition pos, String key, Object... args) {
2484 resultInfo.checkContext.report(pos, diags.fragment("bad.intersection.target.for.functional.expr",
2485 diags.fragment(key, args)));
2486 }
2487 };
2488
2489 private Type fallbackDescriptorType(JCExpression tree) {
2490 switch (tree.getTag()) {
2491 case LAMBDA:
2492 JCLambda lambda = (JCLambda)tree;
2493 List<Type> argtypes = List.nil();
2494 for (JCVariableDecl param : lambda.params) {
2495 argtypes = param.vartype != null ?
2496 argtypes.append(param.vartype.type) :
2497 argtypes.append(syms.errType);
2498 }
2499 return new MethodType(argtypes, Type.recoveryType,
2500 List.of(syms.throwableType), syms.methodClass);
2501 case REFERENCE:
2502 return new MethodType(List.<Type>nil(), Type.recoveryType,
2503 List.of(syms.throwableType), syms.methodClass);
2504 default:
2505 Assert.error("Cannot get here!");
2506 }
2507 return null;
2508 }
2509
2510 private void checkAccessibleTypes(final DiagnosticPosition pos, final Env<AttrContext> env,
2511 final InferenceContext inferenceContext, final Type... ts) {
2512 checkAccessibleTypes(pos, env, inferenceContext, List.from(ts));
2513 }
2514
2515 private void checkAccessibleTypes(final DiagnosticPosition pos, final Env<AttrContext> env,
2516 final InferenceContext inferenceContext, final List<Type> ts) {
2517 if (inferenceContext.free(ts)) {
2518 inferenceContext.addFreeTypeListener(ts, new FreeTypeListener() {
2519 @Override
2520 public void typesInferred(InferenceContext inferenceContext) {
2521 checkAccessibleTypes(pos, env, inferenceContext, inferenceContext.asInstTypes(ts));
2522 }
2523 });
2524 } else {
2525 for (Type t : ts) {
2526 rs.checkAccessibleType(env, t);
2527 }
2528 }
2529 }
2530
2531 /**
2532 * Lambda/method reference have a special check context that ensures
2533 * that i.e. a lambda return type is compatible with the expected
2534 * type according to both the inherited context and the assignment
2535 * context.
2536 */
2537 class FunctionalReturnContext extends Check.NestedCheckContext {
2538
2539 FunctionalReturnContext(CheckContext enclosingContext) {
2540 super(enclosingContext);
2541 }
2542
2543 @Override
2544 public boolean compatible(Type found, Type req, Warner warn) {
2545 //return type must be compatible in both current context and assignment context
2546 return chk.basicHandler.compatible(found, inferenceContext().asFree(req), warn);
2547 }
2548
2549 @Override
2550 public void report(DiagnosticPosition pos, JCDiagnostic details) {
2551 enclosingContext.report(pos, diags.fragment("incompatible.ret.type.in.lambda", details));
2552 }
2553 }
2554
2555 class ExpressionLambdaReturnContext extends FunctionalReturnContext {
2556
2557 JCExpression expr;
2558
2559 ExpressionLambdaReturnContext(JCExpression expr, CheckContext enclosingContext) {
2560 super(enclosingContext);
2561 this.expr = expr;
2562 }
2563
2564 @Override
2565 public boolean compatible(Type found, Type req, Warner warn) {
2566 //a void return is compatible with an expression statement lambda
2567 return TreeInfo.isExpressionStatement(expr) && req.hasTag(VOID) ||
2568 super.compatible(found, req, warn);
2569 }
2570 }
2571
2572 /**
2573 * Lambda compatibility. Check that given return types, thrown types, parameter types
2574 * are compatible with the expected functional interface descriptor. This means that:
2575 * (i) parameter types must be identical to those of the target descriptor; (ii) return
2576 * types must be compatible with the return type of the expected descriptor;
2577 * (iii) thrown types must be 'included' in the thrown types list of the expected
2578 * descriptor.
2579 */
2580 private void checkLambdaCompatible(JCLambda tree, Type descriptor, CheckContext checkContext, boolean speculativeAttr) {
2581 Type returnType = checkContext.inferenceContext().asFree(descriptor.getReturnType());
2582
2583 //return values have already been checked - but if lambda has no return
2584 //values, we must ensure that void/value compatibility is correct;
2585 //this amounts at checking that, if a lambda body can complete normally,
2586 //the descriptor's return type must be void
2587 if (tree.getBodyKind() == JCLambda.BodyKind.STATEMENT && tree.canCompleteNormally &&
2588 !returnType.hasTag(VOID) && returnType != Type.recoveryType) {
2589 checkContext.report(tree, diags.fragment("incompatible.ret.type.in.lambda",
2590 diags.fragment("missing.ret.val", returnType)));
2591 }
2592
2593 List<Type> argTypes = checkContext.inferenceContext().asFree(descriptor.getParameterTypes());
2594 if (!types.isSameTypes(argTypes, TreeInfo.types(tree.params))) {
2595 checkContext.report(tree, diags.fragment("incompatible.arg.types.in.lambda"));
2596 }
2597
2598 if (!speculativeAttr) {
2599 List<Type> thrownTypes = checkContext.inferenceContext().asFree(descriptor.getThrownTypes());
2600 if (chk.unhandled(tree.inferredThrownTypes == null ? List.<Type>nil() : tree.inferredThrownTypes, thrownTypes).nonEmpty()) {
2601 log.error(tree, "incompatible.thrown.types.in.lambda", tree.inferredThrownTypes);
2602 }
2603 }
2604 }
2605
2606 private Env<AttrContext> lambdaEnv(JCLambda that, Env<AttrContext> env) {
2607 Env<AttrContext> lambdaEnv;
2608 Symbol owner = env.info.scope.owner;
2609 if (owner.kind == VAR && owner.owner.kind == TYP) {
2610 //field initializer
2611 lambdaEnv = env.dup(that, env.info.dup(env.info.scope.dupUnshared()));
2612 lambdaEnv.info.scope.owner =
2613 new MethodSymbol(0, names.empty, null,
2614 env.info.scope.owner);
2615 } else {
2616 lambdaEnv = env.dup(that, env.info.dup(env.info.scope.dup()));
2617 }
2618 return lambdaEnv;
2619 }
2620
2621 @Override
2622 public void visitReference(final JCMemberReference that) {
2623 if (pt().isErroneous() || (pt().hasTag(NONE) && pt() != Type.recoveryType)) {
2624 if (pt().hasTag(NONE)) {
2625 //method reference only allowed in assignment or method invocation/cast context
2626 log.error(that.pos(), "unexpected.mref");
2627 }
2628 result = that.type = types.createErrorType(pt());
2629 return;
2630 }
2631 final Env<AttrContext> localEnv = env.dup(that);
2632 try {
2633 //attribute member reference qualifier - if this is a constructor
2634 //reference, the expected kind must be a type
2635 Type exprType = attribTree(that.expr, env, memberReferenceQualifierResult(that));
2636
2637 if (that.getMode() == JCMemberReference.ReferenceMode.NEW) {
2638 exprType = chk.checkConstructorRefType(that.expr, exprType);
2639 }
2640
2641 if (exprType.isErroneous()) {
2642 //if the qualifier expression contains problems,
2643 //give up attribution of method reference
2644 result = that.type = exprType;
2645 return;
2646 }
2647
2648 if (TreeInfo.isStaticSelector(that.expr, names)) {
2649 //if the qualifier is a type, validate it; raw warning check is
2650 //omitted as we don't know at this stage as to whether this is a
2651 //raw selector (because of inference)
2652 chk.validate(that.expr, env, false);
2653 }
2654
2655 //attrib type-arguments
2656 List<Type> typeargtypes = List.nil();
2657 if (that.typeargs != null) {
2658 typeargtypes = attribTypes(that.typeargs, localEnv);
2659 }
2660
2661 Type target;
2662 Type desc;
2663 if (pt() != Type.recoveryType) {
2664 target = targetChecker.visit(pt(), that);
2665 desc = types.findDescriptorType(target);
2666 chk.checkFunctionalInterface(that, target);
2667 } else {
2668 target = Type.recoveryType;
2669 desc = fallbackDescriptorType(that);
2670 }
2671
2672 setFunctionalInfo(that, pt(), desc, target, resultInfo.checkContext.inferenceContext());
2673 List<Type> argtypes = desc.getParameterTypes();
2674
2675 Pair<Symbol, Resolve.ReferenceLookupHelper> refResult =
2676 rs.resolveMemberReference(that.pos(), localEnv, that,
2677 that.expr.type, that.name, argtypes, typeargtypes, true, rs.resolveMethodCheck);
2678
2679 Symbol refSym = refResult.fst;
2680 Resolve.ReferenceLookupHelper lookupHelper = refResult.snd;
2681
2682 if (refSym.kind != MTH) {
2683 boolean targetError;
2684 switch (refSym.kind) {
2685 case ABSENT_MTH:
2686 targetError = false;
2687 break;
2688 case WRONG_MTH:
2689 case WRONG_MTHS:
2690 case AMBIGUOUS:
2691 case HIDDEN:
2692 case STATICERR:
2693 case MISSING_ENCL:
2694 targetError = true;
2695 break;
2696 default:
2697 Assert.error("unexpected result kind " + refSym.kind);
2698 targetError = false;
2699 }
2700
2701 JCDiagnostic detailsDiag = ((Resolve.ResolveError)refSym).getDiagnostic(JCDiagnostic.DiagnosticType.FRAGMENT,
2702 that, exprType.tsym, exprType, that.name, argtypes, typeargtypes);
2703
2704 JCDiagnostic.DiagnosticType diagKind = targetError ?
2705 JCDiagnostic.DiagnosticType.FRAGMENT : JCDiagnostic.DiagnosticType.ERROR;
2706
2707 JCDiagnostic diag = diags.create(diagKind, log.currentSource(), that,
2708 "invalid.mref", Kinds.kindName(that.getMode()), detailsDiag);
2709
2710 if (targetError && target == Type.recoveryType) {
2711 //a target error doesn't make sense during recovery stage
2712 //as we don't know what actual parameter types are
2713 result = that.type = target;
2714 return;
2715 } else {
2716 if (targetError) {
2717 resultInfo.checkContext.report(that, diag);
2718 } else {
2719 log.report(diag);
2720 }
2721 result = that.type = types.createErrorType(target);
2722 return;
2723 }
2724 }
2725
2726 that.sym = refSym.baseSymbol();
2727 that.kind = lookupHelper.referenceKind(that.sym);
2728 that.ownerAccessible = rs.isAccessible(localEnv, that.sym.enclClass());
2729
2730 if (desc.getReturnType() == Type.recoveryType) {
2731 // stop here
2732 result = that.type = target;
2733 return;
2734 }
2735
2736 if (resultInfo.checkContext.deferredAttrContext().mode == AttrMode.CHECK) {
2737
2738 if (that.getMode() == ReferenceMode.INVOKE &&
2739 TreeInfo.isStaticSelector(that.expr, names) &&
2740 that.kind.isUnbound() &&
2741 !desc.getParameterTypes().head.isParameterized()) {
2742 chk.checkRaw(that.expr, localEnv);
2743 }
2744
2745 if (!that.kind.isUnbound() &&
2746 that.getMode() == ReferenceMode.INVOKE &&
2747 TreeInfo.isStaticSelector(that.expr, names) &&
2748 !that.sym.isStatic()) {
2749 log.error(that.expr.pos(), "invalid.mref", Kinds.kindName(that.getMode()),
2750 diags.fragment("non-static.cant.be.ref", Kinds.kindName(refSym), refSym));
2751 result = that.type = types.createErrorType(target);
2752 return;
2753 }
2754
2755 if (that.kind.isUnbound() &&
2756 that.getMode() == ReferenceMode.INVOKE &&
2757 TreeInfo.isStaticSelector(that.expr, names) &&
2758 that.sym.isStatic()) {
2759 log.error(that.expr.pos(), "invalid.mref", Kinds.kindName(that.getMode()),
2760 diags.fragment("static.method.in.unbound.lookup", Kinds.kindName(refSym), refSym));
2761 result = that.type = types.createErrorType(target);
2762 return;
2763 }
2764
2765 if (that.sym.isStatic() && TreeInfo.isStaticSelector(that.expr, names) &&
2766 exprType.getTypeArguments().nonEmpty()) {
2767 //static ref with class type-args
2768 log.error(that.expr.pos(), "invalid.mref", Kinds.kindName(that.getMode()),
2769 diags.fragment("static.mref.with.targs"));
2770 result = that.type = types.createErrorType(target);
2771 return;
2772 }
2773
2774 if (that.sym.isStatic() && !TreeInfo.isStaticSelector(that.expr, names) &&
2775 !that.kind.isUnbound()) {
2776 //no static bound mrefs
2777 log.error(that.expr.pos(), "invalid.mref", Kinds.kindName(that.getMode()),
2778 diags.fragment("static.bound.mref"));
2779 result = that.type = types.createErrorType(target);
2780 return;
2781 }
2782
2783 if (!refSym.isStatic() && that.kind == JCMemberReference.ReferenceKind.SUPER) {
2784 // Check that super-qualified symbols are not abstract (JLS)
2785 rs.checkNonAbstract(that.pos(), that.sym);
2786 }
2787 }
2788
2789 that.sym = refSym.baseSymbol();
2790 that.kind = lookupHelper.referenceKind(that.sym);
2791
2792 ResultInfo checkInfo =
2793 resultInfo.dup(newMethodTemplate(
2794 desc.getReturnType().hasTag(VOID) ? Type.noType : desc.getReturnType(),
2795 lookupHelper.argtypes,
2796 typeargtypes));
2797
2798 Type refType = checkId(that, lookupHelper.site, refSym, localEnv, checkInfo);
2799
2800 if (!refType.isErroneous()) {
2801 refType = types.createMethodTypeWithReturn(refType,
2802 adjustMethodReturnType(lookupHelper.site, that.name, checkInfo.pt.getParameterTypes(), refType.getReturnType()));
2803 }
2804
2805 //go ahead with standard method reference compatibility check - note that param check
2806 //is a no-op (as this has been taken care during method applicability)
2807 boolean isSpeculativeRound =
2808 resultInfo.checkContext.deferredAttrContext().mode == DeferredAttr.AttrMode.SPECULATIVE;
2809 checkReferenceCompatible(that, desc, refType, resultInfo.checkContext, isSpeculativeRound);
2810 if (!isSpeculativeRound) {
2811 checkAccessibleTypes(that, localEnv, resultInfo.checkContext.inferenceContext(), desc, target);
2812 }
2813 result = check(that, target, VAL, resultInfo);
2814 } catch (Types.FunctionDescriptorLookupError ex) {
2815 JCDiagnostic cause = ex.getDiagnostic();
2816 resultInfo.checkContext.report(that, cause);
2817 result = that.type = types.createErrorType(pt());
2818 return;
2819 }
2820 }
2821 //where
2822 ResultInfo memberReferenceQualifierResult(JCMemberReference tree) {
2823 //if this is a constructor reference, the expected kind must be a type
2824 return new ResultInfo(tree.getMode() == ReferenceMode.INVOKE ? VAL | TYP : TYP, Type.noType);
2825 }
2826
2827
2828 @SuppressWarnings("fallthrough")
2829 void checkReferenceCompatible(JCMemberReference tree, Type descriptor, Type refType, CheckContext checkContext, boolean speculativeAttr) {
2830 Type returnType = checkContext.inferenceContext().asFree(descriptor.getReturnType());
2831
2832 Type resType;
2833 switch (tree.getMode()) {
2834 case NEW:
2835 if (!tree.expr.type.isRaw()) {
2836 resType = tree.expr.type;
2837 break;
2838 }
2839 default:
2840 resType = refType.getReturnType();
2841 }
2842
2843 Type incompatibleReturnType = resType;
2844
2845 if (returnType.hasTag(VOID)) {
2846 incompatibleReturnType = null;
2847 }
2848
2849 if (!returnType.hasTag(VOID) && !resType.hasTag(VOID)) {
2850 if (resType.isErroneous() ||
2851 new FunctionalReturnContext(checkContext).compatible(resType, returnType, types.noWarnings)) {
2852 incompatibleReturnType = null;
2853 }
2854 }
2855
2856 if (incompatibleReturnType != null) {
2857 checkContext.report(tree, diags.fragment("incompatible.ret.type.in.mref",
2858 diags.fragment("inconvertible.types", resType, descriptor.getReturnType())));
2859 }
2860
2861 if (!speculativeAttr) {
2862 List<Type> thrownTypes = checkContext.inferenceContext().asFree(descriptor.getThrownTypes());
2863 if (chk.unhandled(refType.getThrownTypes(), thrownTypes).nonEmpty()) {
2864 log.error(tree, "incompatible.thrown.types.in.mref", refType.getThrownTypes());
2865 }
2866 }
2867 }
2868
2869 /**
2870 * Set functional type info on the underlying AST. Note: as the target descriptor
2871 * might contain inference variables, we might need to register an hook in the
2872 * current inference context.
2873 */
2874 private void setFunctionalInfo(final JCFunctionalExpression fExpr, final Type pt,
2875 final Type descriptorType, final Type primaryTarget, InferenceContext inferenceContext) {
2876 if (inferenceContext.free(descriptorType)) {
2877 inferenceContext.addFreeTypeListener(List.of(pt, descriptorType), new FreeTypeListener() {
2878 public void typesInferred(InferenceContext inferenceContext) {
2879 setFunctionalInfo(fExpr, pt, inferenceContext.asInstType(descriptorType),
2880 inferenceContext.asInstType(primaryTarget), inferenceContext);
2881 }
2882 });
2883 } else {
2884 ListBuffer<TypeSymbol> targets = ListBuffer.lb();
2885 if (pt.hasTag(CLASS)) {
2886 if (pt.isCompound()) {
2887 targets.append(primaryTarget.tsym); //this goes first
2888 for (Type t : ((IntersectionClassType)pt()).interfaces_field) {
2889 if (t != primaryTarget) {
2890 targets.append(t.tsym);
2891 }
2892 }
2893 } else {
2894 targets.append(pt.tsym);
2895 }
2896 }
2897 fExpr.targets = targets.toList();
2898 fExpr.descriptorType = descriptorType;
2899 }
2900 }
2901
2902 public void visitParens(JCParens tree) {
2903 Type owntype = attribTree(tree.expr, env, resultInfo);
2904 result = check(tree, owntype, pkind(), resultInfo);
2905 Symbol sym = TreeInfo.symbol(tree);
2906 if (sym != null && (sym.kind&(TYP|PCK)) != 0)
2907 log.error(tree.pos(), "illegal.start.of.type");
2908 }
2909
2910 public void visitAssign(JCAssign tree) {
2911 Type owntype = attribTree(tree.lhs, env.dup(tree), varInfo);
2912 Type capturedType = capture(owntype);
2913 attribExpr(tree.rhs, env, owntype);
2914 result = check(tree, capturedType, VAL, resultInfo);
2915 }
2916
2917 public void visitAssignop(JCAssignOp tree) {
2918 // Attribute arguments.
2919 Type owntype = attribTree(tree.lhs, env, varInfo);
2920 Type operand = attribExpr(tree.rhs, env);
2921 // Find operator.
2922 Symbol operator = tree.operator = rs.resolveBinaryOperator(
2923 tree.pos(), tree.getTag().noAssignOp(), env,
2924 owntype, operand);
2925
2926 if (operator.kind == MTH &&
2927 !owntype.isErroneous() &&
2928 !operand.isErroneous()) {
2929 chk.checkOperator(tree.pos(),
2930 (OperatorSymbol)operator,
2931 tree.getTag().noAssignOp(),
2932 owntype,
2933 operand);
2934 chk.checkDivZero(tree.rhs.pos(), operator, operand);
2935 chk.checkCastable(tree.rhs.pos(),
2936 operator.type.getReturnType(),
2937 owntype);
2938 }
2939 result = check(tree, owntype, VAL, resultInfo);
2940 }
2941
2942 public void visitUnary(JCUnary tree) {
2943 // Attribute arguments.
2944 Type argtype = (tree.getTag().isIncOrDecUnaryOp())
2945 ? attribTree(tree.arg, env, varInfo)
2946 : chk.checkNonVoid(tree.arg.pos(), attribExpr(tree.arg, env));
2947
2948 // Find operator.
2949 Symbol operator = tree.operator =
2950 rs.resolveUnaryOperator(tree.pos(), tree.getTag(), env, argtype);
2951
2952 Type owntype = types.createErrorType(tree.type);
2953 if (operator.kind == MTH &&
2954 !argtype.isErroneous()) {
2955 owntype = (tree.getTag().isIncOrDecUnaryOp())
2956 ? tree.arg.type
2957 : operator.type.getReturnType();
2958 int opc = ((OperatorSymbol)operator).opcode;
2959
2960 // If the argument is constant, fold it.
2961 if (argtype.constValue() != null) {
2962 Type ctype = cfolder.fold1(opc, argtype);
2963 if (ctype != null) {
2964 owntype = cfolder.coerce(ctype, owntype);
2965
2966 // Remove constant types from arguments to
2967 // conserve space. The parser will fold concatenations
2968 // of string literals; the code here also
2969 // gets rid of intermediate results when some of the
2970 // operands are constant identifiers.
2971 if (tree.arg.type.tsym == syms.stringType.tsym) {
2972 tree.arg.type = syms.stringType;
2973 }
2974 }
2975 }
2976 }
2977 result = check(tree, owntype, VAL, resultInfo);
2978 }
2979
2980 public void visitBinary(JCBinary tree) {
2981 // Attribute arguments.
2982 Type left = chk.checkNonVoid(tree.lhs.pos(), attribExpr(tree.lhs, env));
2983 Type right = chk.checkNonVoid(tree.lhs.pos(), attribExpr(tree.rhs, env));
2984
2985 // Find operator.
2986 Symbol operator = tree.operator =
2987 rs.resolveBinaryOperator(tree.pos(), tree.getTag(), env, left, right);
2988
2989 Type owntype = types.createErrorType(tree.type);
2990 if (operator.kind == MTH &&
2991 !left.isErroneous() &&
2992 !right.isErroneous()) {
2993 owntype = operator.type.getReturnType();
2994 // This will figure out when unboxing can happen and
2995 // choose the right comparison operator.
2996 int opc = chk.checkOperator(tree.lhs.pos(),
2997 (OperatorSymbol)operator,
2998 tree.getTag(),
2999 left,
3000 right);
3001
3002 // If both arguments are constants, fold them.
3003 if (left.constValue() != null && right.constValue() != null) {
3004 Type ctype = cfolder.fold2(opc, left, right);
3005 if (ctype != null) {
3006 owntype = cfolder.coerce(ctype, owntype);
3007
3008 // Remove constant types from arguments to
3009 // conserve space. The parser will fold concatenations
3010 // of string literals; the code here also
3011 // gets rid of intermediate results when some of the
3012 // operands are constant identifiers.
3013 if (tree.lhs.type.tsym == syms.stringType.tsym) {
3014 tree.lhs.type = syms.stringType;
3015 }
3016 if (tree.rhs.type.tsym == syms.stringType.tsym) {
3017 tree.rhs.type = syms.stringType;
3018 }
3019 }
3020 }
3021
3022 // Check that argument types of a reference ==, != are
3023 // castable to each other, (JLS 15.21). Note: unboxing
3024 // comparisons will not have an acmp* opc at this point.
3025 if ((opc == ByteCodes.if_acmpeq || opc == ByteCodes.if_acmpne)) {
3026 if (!types.isEqualityComparable(left, right,
3027 new Warner(tree.pos()))) {
3028 log.error(tree.pos(), "incomparable.types", left, right);
3029 }
3030 }
3031
3032 chk.checkDivZero(tree.rhs.pos(), operator, right);
3033 }
3034 result = check(tree, owntype, VAL, resultInfo);
3035 }
3036
3037 public void visitTypeCast(final JCTypeCast tree) {
3038 Type clazztype = attribType(tree.clazz, env);
3039 chk.validate(tree.clazz, env, false);
3040 //a fresh environment is required for 292 inference to work properly ---
3041 //see Infer.instantiatePolymorphicSignatureInstance()
3042 Env<AttrContext> localEnv = env.dup(tree);
3043 //should we propagate the target type?
3044 final ResultInfo castInfo;
3045 JCExpression expr = TreeInfo.skipParens(tree.expr);
3046 boolean isPoly = expr.hasTag(LAMBDA) || expr.hasTag(REFERENCE);
3047 if (isPoly) {
3048 //expression is a poly - we need to propagate target type info
3049 castInfo = new ResultInfo(VAL, clazztype, new Check.NestedCheckContext(resultInfo.checkContext) {
3050 @Override
3051 public boolean compatible(Type found, Type req, Warner warn) {
3052 return types.isCastable(found, req, warn);
3053 }
3054 });
3055 } else {
3056 //standalone cast - target-type info is not propagated
3057 castInfo = unknownExprInfo;
3058 }
3059 Type exprtype = attribTree(tree.expr, localEnv, castInfo);
3060 Type owntype = isPoly ? clazztype : chk.checkCastable(tree.expr.pos(), exprtype, clazztype);
3061 if (exprtype.constValue() != null)
3062 owntype = cfolder.coerce(exprtype, owntype);
3063 result = check(tree, capture(owntype), VAL, resultInfo);
3064 if (!isPoly)
3065 chk.checkRedundantCast(localEnv, tree);
3066 }
3067
3068 public void visitTypeTest(JCInstanceOf tree) {
3069 Type exprtype = chk.checkNullOrRefType(
3070 tree.expr.pos(), attribExpr(tree.expr, env));
3071 Type clazztype = chk.checkReifiableReferenceType(
3072 tree.clazz.pos(), attribType(tree.clazz, env));
3073 chk.validate(tree.clazz, env, false);
3074 chk.checkCastable(tree.expr.pos(), exprtype, clazztype);
3075 result = check(tree, syms.booleanType, VAL, resultInfo);
3076 }
3077
3078 public void visitIndexed(JCArrayAccess tree) {
3079 Type owntype = types.createErrorType(tree.type);
3080 Type atype = attribExpr(tree.indexed, env);
3081 attribExpr(tree.index, env, syms.intType);
3082 if (types.isArray(atype))
3083 owntype = types.elemtype(atype);
3084 else if (!atype.hasTag(ERROR))
3085 log.error(tree.pos(), "array.req.but.found", atype);
3086 if ((pkind() & VAR) == 0) owntype = capture(owntype);
3087 result = check(tree, owntype, VAR, resultInfo);
3088 }
3089
3090 public void visitIdent(JCIdent tree) {
3091 Symbol sym;
3092
3093 // Find symbol
3094 if (pt().hasTag(METHOD) || pt().hasTag(FORALL)) {
3095 // If we are looking for a method, the prototype `pt' will be a
3096 // method type with the type of the call's arguments as parameters.
3097 env.info.pendingResolutionPhase = null;
3098 sym = rs.resolveMethod(tree.pos(), env, tree.name, pt().getParameterTypes(), pt().getTypeArguments());
3099 } else if (tree.sym != null && tree.sym.kind != VAR) {
3100 sym = tree.sym;
3101 } else {
3102 sym = rs.resolveIdent(tree.pos(), env, tree.name, pkind());
3103 }
3104 tree.sym = sym;
3105
3106 // (1) Also find the environment current for the class where
3107 // sym is defined (`symEnv').
3108 // Only for pre-tiger versions (1.4 and earlier):
3109 // (2) Also determine whether we access symbol out of an anonymous
3110 // class in a this or super call. This is illegal for instance
3111 // members since such classes don't carry a this$n link.
3112 // (`noOuterThisPath').
3113 Env<AttrContext> symEnv = env;
3114 boolean noOuterThisPath = false;
3115 if (env.enclClass.sym.owner.kind != PCK && // we are in an inner class
3116 (sym.kind & (VAR | MTH | TYP)) != 0 &&
3117 sym.owner.kind == TYP &&
3118 tree.name != names._this && tree.name != names._super) {
3119
3120 // Find environment in which identifier is defined.
3121 while (symEnv.outer != null &&
3122 !sym.isMemberOf(symEnv.enclClass.sym, types)) {
3123 if ((symEnv.enclClass.sym.flags() & NOOUTERTHIS) != 0)
3124 noOuterThisPath = !allowAnonOuterThis;
3125 symEnv = symEnv.outer;
3126 }
3127 }
3128
3129 // If symbol is a variable, ...
3130 if (sym.kind == VAR) {
3131 VarSymbol v = (VarSymbol)sym;
3132
3133 // ..., evaluate its initializer, if it has one, and check for
3134 // illegal forward reference.
3135 checkInit(tree, env, v, false);
3136
3137 // If we are expecting a variable (as opposed to a value), check
3138 // that the variable is assignable in the current environment.
3139 if (pkind() == VAR)
3140 checkAssignable(tree.pos(), v, null, env);
3141 }
3142
3143 // In a constructor body,
3144 // if symbol is a field or instance method, check that it is
3145 // not accessed before the supertype constructor is called.
3146 if ((symEnv.info.isSelfCall || noOuterThisPath) &&
3147 (sym.kind & (VAR | MTH)) != 0 &&
3148 sym.owner.kind == TYP &&
3149 (sym.flags() & STATIC) == 0) {
3150 chk.earlyRefError(tree.pos(), sym.kind == VAR ? sym : thisSym(tree.pos(), env));
3151 }
3152 Env<AttrContext> env1 = env;
3153 if (sym.kind != ERR && sym.kind != TYP && sym.owner != null && sym.owner != env1.enclClass.sym) {
3154 // If the found symbol is inaccessible, then it is
3155 // accessed through an enclosing instance. Locate this
3156 // enclosing instance:
3157 while (env1.outer != null && !rs.isAccessible(env, env1.enclClass.sym.type, sym))
3158 env1 = env1.outer;
3159 }
3160 result = checkId(tree, env1.enclClass.sym.type, sym, env, resultInfo);
3161 }
3162
3163 public void visitSelect(JCFieldAccess tree) {
3164 // Determine the expected kind of the qualifier expression.
3165 int skind = 0;
3166 if (tree.name == names._this || tree.name == names._super ||
3167 tree.name == names._class)
3168 {
3169 skind = TYP;
3170 } else {
3171 if ((pkind() & PCK) != 0) skind = skind | PCK;
3172 if ((pkind() & TYP) != 0) skind = skind | TYP | PCK;
3173 if ((pkind() & (VAL | MTH)) != 0) skind = skind | VAL | TYP;
3174 }
3175
3176 // Attribute the qualifier expression, and determine its symbol (if any).
3177 Type site = attribTree(tree.selected, env, new ResultInfo(skind, Infer.anyPoly));
3178 if ((pkind() & (PCK | TYP)) == 0)
3179 site = capture(site); // Capture field access
3180
3181 // don't allow T.class T[].class, etc
3182 if (skind == TYP) {
3183 Type elt = site;
3184 while (elt.hasTag(ARRAY))
3185 elt = ((ArrayType)elt).elemtype;
3186 if (elt.hasTag(TYPEVAR)) {
3187 log.error(tree.pos(), "type.var.cant.be.deref");
3188 result = types.createErrorType(tree.type);
3189 return;
3190 }
3191 }
3192
3193 // If qualifier symbol is a type or `super', assert `selectSuper'
3194 // for the selection. This is relevant for determining whether
3195 // protected symbols are accessible.
3196 Symbol sitesym = TreeInfo.symbol(tree.selected);
3197 boolean selectSuperPrev = env.info.selectSuper;
3198 env.info.selectSuper =
3199 sitesym != null &&
3200 sitesym.name == names._super;
3201
3202 // Determine the symbol represented by the selection.
3203 env.info.pendingResolutionPhase = null;
3204 Symbol sym = selectSym(tree, sitesym, site, env, resultInfo);
3205 if (sym.exists() && !isType(sym) && (pkind() & (PCK | TYP)) != 0) {
3206 site = capture(site);
3207 sym = selectSym(tree, sitesym, site, env, resultInfo);
3208 }
3209 boolean varArgs = env.info.lastResolveVarargs();
3210 tree.sym = sym;
3211
3212 if (site.hasTag(TYPEVAR) && !isType(sym) && sym.kind != ERR) {
3213 while (site.hasTag(TYPEVAR)) site = site.getUpperBound();
3214 site = capture(site);
3215 }
3216
3217 // If that symbol is a variable, ...
3218 if (sym.kind == VAR) {
3219 VarSymbol v = (VarSymbol)sym;
3220
3221 // ..., evaluate its initializer, if it has one, and check for
3222 // illegal forward reference.
3223 checkInit(tree, env, v, true);
3224
3225 // If we are expecting a variable (as opposed to a value), check
3226 // that the variable is assignable in the current environment.
3227 if (pkind() == VAR)
3228 checkAssignable(tree.pos(), v, tree.selected, env);
3229 }
3230
3231 if (sitesym != null &&
3232 sitesym.kind == VAR &&
3233 ((VarSymbol)sitesym).isResourceVariable() &&
3234 sym.kind == MTH &&
3235 sym.name.equals(names.close) &&
3236 sym.overrides(syms.autoCloseableClose, sitesym.type.tsym, types, true) &&
3237 env.info.lint.isEnabled(LintCategory.TRY)) {
3238 log.warning(LintCategory.TRY, tree, "try.explicit.close.call");
3239 }
3240
3241 // Disallow selecting a type from an expression
3242 if (isType(sym) && (sitesym==null || (sitesym.kind&(TYP|PCK)) == 0)) {
3243 tree.type = check(tree.selected, pt(),
3244 sitesym == null ? VAL : sitesym.kind, new ResultInfo(TYP|PCK, pt()));
3245 }
3246
3247 if (isType(sitesym)) {
3248 if (sym.name == names._this) {
3249 // If `C' is the currently compiled class, check that
3250 // C.this' does not appear in a call to a super(...)
3251 if (env.info.isSelfCall &&
3252 site.tsym == env.enclClass.sym) {
3253 chk.earlyRefError(tree.pos(), sym);
3254 }
3255 } else {
3256 // Check if type-qualified fields or methods are static (JLS)
3257 if ((sym.flags() & STATIC) == 0 &&
3258 !env.next.tree.hasTag(REFERENCE) &&
3259 sym.name != names._super &&
3260 (sym.kind == VAR || sym.kind == MTH)) {
3261 rs.accessBase(rs.new StaticError(sym),
3262 tree.pos(), site, sym.name, true);
3263 }
3264 }
3265 } else if (sym.kind != ERR && (sym.flags() & STATIC) != 0 && sym.name != names._class) {
3266 // If the qualified item is not a type and the selected item is static, report
3267 // a warning. Make allowance for the class of an array type e.g. Object[].class)
3268 chk.warnStatic(tree, "static.not.qualified.by.type", Kinds.kindName(sym.kind), sym.owner);
3269 }
3270
3271 // If we are selecting an instance member via a `super', ...
3272 if (env.info.selectSuper && (sym.flags() & STATIC) == 0) {
3273
3274 // Check that super-qualified symbols are not abstract (JLS)
3275 rs.checkNonAbstract(tree.pos(), sym);
3276
3277 if (site.isRaw()) {
3278 // Determine argument types for site.
3279 Type site1 = types.asSuper(env.enclClass.sym.type, site.tsym);
3280 if (site1 != null) site = site1;
3281 }
3282 }
3283
3284 env.info.selectSuper = selectSuperPrev;
3285 result = checkId(tree, site, sym, env, resultInfo);
3286 }
3287 //where
3288 /** Determine symbol referenced by a Select expression,
3289 *
3290 * @param tree The select tree.
3291 * @param site The type of the selected expression,
3292 * @param env The current environment.
3293 * @param resultInfo The current result.
3294 */
3295 private Symbol selectSym(JCFieldAccess tree,
3296 Symbol location,
3297 Type site,
3298 Env<AttrContext> env,
3299 ResultInfo resultInfo) {
3300 DiagnosticPosition pos = tree.pos();
3301 Name name = tree.name;
3302 switch (site.getTag()) {
3303 case PACKAGE:
3304 return rs.accessBase(
3305 rs.findIdentInPackage(env, site.tsym, name, resultInfo.pkind),
3306 pos, location, site, name, true);
3307 case ARRAY:
3308 case CLASS:
3309 if (resultInfo.pt.hasTag(METHOD) || resultInfo.pt.hasTag(FORALL)) {
3310 return rs.resolveQualifiedMethod(
3311 pos, env, location, site, name, resultInfo.pt.getParameterTypes(), resultInfo.pt.getTypeArguments());
3312 } else if (name == names._this || name == names._super) {
3313 return rs.resolveSelf(pos, env, site.tsym, name);
3314 } else if (name == names._class) {
3315 // In this case, we have already made sure in
3316 // visitSelect that qualifier expression is a type.
3317 Type t = syms.classType;
3318 List<Type> typeargs = allowGenerics
3319 ? List.of(types.erasure(site))
3320 : List.<Type>nil();
3321 t = new ClassType(t.getEnclosingType(), typeargs, t.tsym);
3322 return new VarSymbol(
3323 STATIC | PUBLIC | FINAL, names._class, t, site.tsym);
3324 } else {
3325 // We are seeing a plain identifier as selector.
3326 Symbol sym = rs.findIdentInType(env, site, name, resultInfo.pkind);
3327 if ((resultInfo.pkind & ERRONEOUS) == 0)
3328 sym = rs.accessBase(sym, pos, location, site, name, true);
3329 return sym;
3330 }
3331 case WILDCARD:
3332 throw new AssertionError(tree);
3333 case TYPEVAR:
3334 // Normally, site.getUpperBound() shouldn't be null.
3335 // It should only happen during memberEnter/attribBase
3336 // when determining the super type which *must* beac
3337 // done before attributing the type variables. In
3338 // other words, we are seeing this illegal program:
3339 // class B<T> extends A<T.foo> {}
3340 Symbol sym = (site.getUpperBound() != null)
3341 ? selectSym(tree, location, capture(site.getUpperBound()), env, resultInfo)
3342 : null;
3343 if (sym == null) {
3344 log.error(pos, "type.var.cant.be.deref");
3345 return syms.errSymbol;
3346 } else {
3347 Symbol sym2 = (sym.flags() & Flags.PRIVATE) != 0 ?
3348 rs.new AccessError(env, site, sym) :
3349 sym;
3350 rs.accessBase(sym2, pos, location, site, name, true);
3351 return sym;
3352 }
3353 case ERROR:
3354 // preserve identifier names through errors
3355 return types.createErrorType(name, site.tsym, site).tsym;
3356 default:
3357 // The qualifier expression is of a primitive type -- only
3358 // .class is allowed for these.
3359 if (name == names._class) {
3360 // In this case, we have already made sure in Select that
3361 // qualifier expression is a type.
3362 Type t = syms.classType;
3363 Type arg = types.boxedClass(site).type;
3364 t = new ClassType(t.getEnclosingType(), List.of(arg), t.tsym);
3365 return new VarSymbol(
3366 STATIC | PUBLIC | FINAL, names._class, t, site.tsym);
3367 } else {
3368 log.error(pos, "cant.deref", site);
3369 return syms.errSymbol;
3370 }
3371 }
3372 }
3373
3374 /** Determine type of identifier or select expression and check that
3375 * (1) the referenced symbol is not deprecated
3376 * (2) the symbol's type is safe (@see checkSafe)
3377 * (3) if symbol is a variable, check that its type and kind are
3378 * compatible with the prototype and protokind.
3379 * (4) if symbol is an instance field of a raw type,
3380 * which is being assigned to, issue an unchecked warning if its
3381 * type changes under erasure.
3382 * (5) if symbol is an instance method of a raw type, issue an
3383 * unchecked warning if its argument types change under erasure.
3384 * If checks succeed:
3385 * If symbol is a constant, return its constant type
3386 * else if symbol is a method, return its result type
3387 * otherwise return its type.
3388 * Otherwise return errType.
3389 *
3390 * @param tree The syntax tree representing the identifier
3391 * @param site If this is a select, the type of the selected
3392 * expression, otherwise the type of the current class.
3393 * @param sym The symbol representing the identifier.
3394 * @param env The current environment.
3395 * @param resultInfo The expected result
3396 */
3397 Type checkId(JCTree tree,
3398 Type site,
3399 Symbol sym,
3400 Env<AttrContext> env,
3401 ResultInfo resultInfo) {
3402 return (resultInfo.pt.hasTag(FORALL) || resultInfo.pt.hasTag(METHOD)) ?
3403 checkMethodId(tree, site, sym, env, resultInfo) :
3404 checkIdInternal(tree, site, sym, resultInfo.pt, env, resultInfo);
3405 }
3406
3407 Type checkMethodId(JCTree tree,
3408 Type site,
3409 Symbol sym,
3410 Env<AttrContext> env,
3411 ResultInfo resultInfo) {
3412 boolean isPolymorhicSignature =
3413 sym.kind == MTH && ((MethodSymbol)sym.baseSymbol()).isSignaturePolymorphic(types);
3414 return isPolymorhicSignature ?
3415 checkSigPolyMethodId(tree, site, sym, env, resultInfo) :
3416 checkMethodIdInternal(tree, site, sym, env, resultInfo);
3417 }
3418
3419 Type checkSigPolyMethodId(JCTree tree,
3420 Type site,
3421 Symbol sym,
3422 Env<AttrContext> env,
3423 ResultInfo resultInfo) {
3424 //recover original symbol for signature polymorphic methods
3425 checkMethodIdInternal(tree, site, sym.baseSymbol(), env, resultInfo);
3426 env.info.pendingResolutionPhase = Resolve.MethodResolutionPhase.BASIC;
3427 return sym.type;
3428 }
3429
3430 Type checkMethodIdInternal(JCTree tree,
3431 Type site,
3432 Symbol sym,
3433 Env<AttrContext> env,
3434 ResultInfo resultInfo) {
3435 Type pt = resultInfo.pt.map(deferredAttr.new RecoveryDeferredTypeMap(AttrMode.SPECULATIVE, sym, env.info.pendingResolutionPhase));
3436 Type owntype = checkIdInternal(tree, site, sym, pt, env, resultInfo);
3437 resultInfo.pt.map(deferredAttr.new RecoveryDeferredTypeMap(AttrMode.CHECK, sym, env.info.pendingResolutionPhase));
3438 return owntype;
3439 }
3440
3441 Type checkIdInternal(JCTree tree,
3442 Type site,
3443 Symbol sym,
3444 Type pt,
3445 Env<AttrContext> env,
3446 ResultInfo resultInfo) {
3447 if (pt.isErroneous()) {
3448 return types.createErrorType(site);
3449 }
3450 Type owntype; // The computed type of this identifier occurrence.
3451 switch (sym.kind) {
3452 case TYP:
3453 // For types, the computed type equals the symbol's type,
3454 // except for two situations:
3455 owntype = sym.type;
3456 if (owntype.hasTag(CLASS)) {
3457 chk.checkForBadAuxiliaryClassAccess(tree.pos(), env, (ClassSymbol)sym);
3458 Type ownOuter = owntype.getEnclosingType();
3459
3460 // (a) If the symbol's type is parameterized, erase it
3461 // because no type parameters were given.
3462 // We recover generic outer type later in visitTypeApply.
3463 if (owntype.tsym.type.getTypeArguments().nonEmpty()) {
3464 owntype = types.erasure(owntype);
3465 }
3466
3467 // (b) If the symbol's type is an inner class, then
3468 // we have to interpret its outer type as a superclass
3469 // of the site type. Example:
3470 //
3471 // class Tree<A> { class Visitor { ... } }
3472 // class PointTree extends Tree<Point> { ... }
3473 // ...PointTree.Visitor...
3474 //
3475 // Then the type of the last expression above is
3476 // Tree<Point>.Visitor.
3477 else if (ownOuter.hasTag(CLASS) && site != ownOuter) {
3478 Type normOuter = site;
3479 if (normOuter.hasTag(CLASS)) {
3480 normOuter = types.asEnclosingSuper(site, ownOuter.tsym);
3481 if (site.isAnnotated()) {
3482 // Propagate any type annotations.
3483 // TODO: should asEnclosingSuper do this?
3484 // Note that the type annotations in site will be updated
3485 // by annotateType. Therefore, modify site instead
3486 // of creating a new AnnotatedType.
3487 ((AnnotatedType)site).underlyingType = normOuter;
3488 normOuter = site;
3489 }
3490 }
3491 if (normOuter == null) // perhaps from an import
3492 normOuter = types.erasure(ownOuter);
3493 if (normOuter != ownOuter)
3494 owntype = new ClassType(
3495 normOuter, List.<Type>nil(), owntype.tsym);
3496 }
3497 }
3498 break;
3499 case VAR:
3500 VarSymbol v = (VarSymbol)sym;
3501 // Test (4): if symbol is an instance field of a raw type,
3502 // which is being assigned to, issue an unchecked warning if
3503 // its type changes under erasure.
3504 if (allowGenerics &&
3505 resultInfo.pkind == VAR &&
3506 v.owner.kind == TYP &&
3507 (v.flags() & STATIC) == 0 &&
3508 (site.hasTag(CLASS) || site.hasTag(TYPEVAR))) {
3509 Type s = types.asOuterSuper(site, v.owner);
3510 if (s != null &&
3511 s.isRaw() &&
3512 !types.isSameType(v.type, v.erasure(types))) {
3513 chk.warnUnchecked(tree.pos(),
3514 "unchecked.assign.to.var",
3515 v, s);
3516 }
3517 }
3518 // The computed type of a variable is the type of the
3519 // variable symbol, taken as a member of the site type.
3520 owntype = (sym.owner.kind == TYP &&
3521 sym.name != names._this && sym.name != names._super)
3522 ? types.memberType(site, sym)
3523 : sym.type;
3524
3525 // If the variable is a constant, record constant value in
3526 // computed type.
3527 if (v.getConstValue() != null && isStaticReference(tree))
3528 owntype = owntype.constType(v.getConstValue());
3529
3530 if (resultInfo.pkind == VAL) {
3531 owntype = capture(owntype); // capture "names as expressions"
3532 }
3533 break;
3534 case MTH: {
3535 owntype = checkMethod(site, sym,
3536 new ResultInfo(VAL, resultInfo.pt.getReturnType(), resultInfo.checkContext),
3537 env, TreeInfo.args(env.tree), resultInfo.pt.getParameterTypes(),
3538 resultInfo.pt.getTypeArguments());
3539 break;
3540 }
3541 case PCK: case ERR:
3542 owntype = sym.type;
3543 break;
3544 default:
3545 throw new AssertionError("unexpected kind: " + sym.kind +
3546 " in tree " + tree);
3547 }
3548
3549 // Test (1): emit a `deprecation' warning if symbol is deprecated.
3550 // (for constructors, the error was given when the constructor was
3551 // resolved)
3552
3553 if (sym.name != names.init) {
3554 chk.checkDeprecated(tree.pos(), env.info.scope.owner, sym);
3555 chk.checkSunAPI(tree.pos(), sym);
3556 chk.checkProfile(tree.pos(), sym);
3557 }
3558
3559 // Test (3): if symbol is a variable, check that its type and
3560 // kind are compatible with the prototype and protokind.
3561 return check(tree, owntype, sym.kind, resultInfo);
3562 }
3563
3564 /** Check that variable is initialized and evaluate the variable's
3565 * initializer, if not yet done. Also check that variable is not
3566 * referenced before it is defined.
3567 * @param tree The tree making up the variable reference.
3568 * @param env The current environment.
3569 * @param v The variable's symbol.
3570 */
3571 private void checkInit(JCTree tree,
3572 Env<AttrContext> env,
3573 VarSymbol v,
3574 boolean onlyWarning) {
3575 // System.err.println(v + " " + ((v.flags() & STATIC) != 0) + " " +
3576 // tree.pos + " " + v.pos + " " +
3577 // Resolve.isStatic(env));//DEBUG
3578
3579 // A forward reference is diagnosed if the declaration position
3580 // of the variable is greater than the current tree position
3581 // and the tree and variable definition occur in the same class
3582 // definition. Note that writes don't count as references.
3583 // This check applies only to class and instance
3584 // variables. Local variables follow different scope rules,
3585 // and are subject to definite assignment checking.
3586 if ((env.info.enclVar == v || v.pos > tree.pos) &&
3587 v.owner.kind == TYP &&
3588 canOwnInitializer(owner(env)) &&
3589 v.owner == env.info.scope.owner.enclClass() &&
3590 ((v.flags() & STATIC) != 0) == Resolve.isStatic(env) &&
3591 (!env.tree.hasTag(ASSIGN) ||
3592 TreeInfo.skipParens(((JCAssign) env.tree).lhs) != tree)) {
3593 String suffix = (env.info.enclVar == v) ?
3594 "self.ref" : "forward.ref";
3595 if (!onlyWarning || isStaticEnumField(v)) {
3596 log.error(tree.pos(), "illegal." + suffix);
3597 } else if (useBeforeDeclarationWarning) {
3598 log.warning(tree.pos(), suffix, v);
3599 }
3600 }
3601
3602 v.getConstValue(); // ensure initializer is evaluated
3603
3604 checkEnumInitializer(tree, env, v);
3605 }
3606
3607 /**
3608 * Check for illegal references to static members of enum. In
3609 * an enum type, constructors and initializers may not
3610 * reference its static members unless they are constant.
3611 *
3612 * @param tree The tree making up the variable reference.
3613 * @param env The current environment.
3614 * @param v The variable's symbol.
3615 * @jls section 8.9 Enums
3616 */
3617 private void checkEnumInitializer(JCTree tree, Env<AttrContext> env, VarSymbol v) {
3618 // JLS:
3619 //
3620 // "It is a compile-time error to reference a static field
3621 // of an enum type that is not a compile-time constant
3622 // (15.28) from constructors, instance initializer blocks,
3623 // or instance variable initializer expressions of that
3624 // type. It is a compile-time error for the constructors,
3625 // instance initializer blocks, or instance variable
3626 // initializer expressions of an enum constant e to refer
3627 // to itself or to an enum constant of the same type that
3628 // is declared to the right of e."
3629 if (isStaticEnumField(v)) {
3630 ClassSymbol enclClass = env.info.scope.owner.enclClass();
3631
3632 if (enclClass == null || enclClass.owner == null)
3633 return;
3634
3635 // See if the enclosing class is the enum (or a
3636 // subclass thereof) declaring v. If not, this
3637 // reference is OK.
3638 if (v.owner != enclClass && !types.isSubtype(enclClass.type, v.owner.type))
3639 return;
3640
3641 // If the reference isn't from an initializer, then
3642 // the reference is OK.
3643 if (!Resolve.isInitializer(env))
3644 return;
3645
3646 log.error(tree.pos(), "illegal.enum.static.ref");
3647 }
3648 }
3649
3650 /** Is the given symbol a static, non-constant field of an Enum?
3651 * Note: enum literals should not be regarded as such
3652 */
3653 private boolean isStaticEnumField(VarSymbol v) {
3654 return Flags.isEnum(v.owner) &&
3655 Flags.isStatic(v) &&
3656 !Flags.isConstant(v) &&
3657 v.name != names._class;
3658 }
3659
3660 /** Can the given symbol be the owner of code which forms part
3661 * if class initialization? This is the case if the symbol is
3662 * a type or field, or if the symbol is the synthetic method.
3663 * owning a block.
3664 */
3665 private boolean canOwnInitializer(Symbol sym) {
3666 return
3667 (sym.kind & (VAR | TYP)) != 0 ||
3668 (sym.kind == MTH && (sym.flags() & BLOCK) != 0);
3669 }
3670
3671 Warner noteWarner = new Warner();
3672
3673 /**
3674 * Check that method arguments conform to its instantiation.
3675 **/
3676 public Type checkMethod(Type site,
3677 Symbol sym,
3678 ResultInfo resultInfo,
3679 Env<AttrContext> env,
3680 final List<JCExpression> argtrees,
3681 List<Type> argtypes,
3682 List<Type> typeargtypes) {
3683 // Test (5): if symbol is an instance method of a raw type, issue
3684 // an unchecked warning if its argument types change under erasure.
3685 if (allowGenerics &&
3686 (sym.flags() & STATIC) == 0 &&
3687 (site.hasTag(CLASS) || site.hasTag(TYPEVAR))) {
3688 Type s = types.asOuterSuper(site, sym.owner);
3689 if (s != null && s.isRaw() &&
3690 !types.isSameTypes(sym.type.getParameterTypes(),
3691 sym.erasure(types).getParameterTypes())) {
3692 chk.warnUnchecked(env.tree.pos(),
3693 "unchecked.call.mbr.of.raw.type",
3694 sym, s);
3695 }
3696 }
3697
3698 if (env.info.defaultSuperCallSite != null) {
3699 for (Type sup : types.interfaces(env.enclClass.type).prepend(types.supertype((env.enclClass.type)))) {
3700 if (!sup.tsym.isSubClass(sym.enclClass(), types) ||
3701 types.isSameType(sup, env.info.defaultSuperCallSite)) continue;
3702 List<MethodSymbol> icand_sup =
3703 types.interfaceCandidates(sup, (MethodSymbol)sym);
3704 if (icand_sup.nonEmpty() &&
3705 icand_sup.head != sym &&
3706 icand_sup.head.overrides(sym, icand_sup.head.enclClass(), types, true)) {
3707 log.error(env.tree.pos(), "illegal.default.super.call", env.info.defaultSuperCallSite,
3708 diags.fragment("overridden.default", sym, sup));
3709 break;
3710 }
3711 }
3712 env.info.defaultSuperCallSite = null;
3713 }
3714
3715 if (sym.isStatic() && site.isInterface() && env.tree.hasTag(APPLY)) {
3716 JCMethodInvocation app = (JCMethodInvocation)env.tree;
3717 if (app.meth.hasTag(SELECT) &&
3718 !TreeInfo.isStaticSelector(((JCFieldAccess)app.meth).selected, names)) {
3719 log.error(env.tree.pos(), "illegal.static.intf.meth.call", site);
3720 }
3721 }
3722
3723 // Compute the identifier's instantiated type.
3724 // For methods, we need to compute the instance type by
3725 // Resolve.instantiate from the symbol's type as well as
3726 // any type arguments and value arguments.
3727 noteWarner.clear();
3728 try {
3729 Type owntype = rs.checkMethod(
3730 env,
3731 site,
3732 sym,
3733 resultInfo,
3734 argtypes,
3735 typeargtypes,
3736 noteWarner);
3737
3738 return chk.checkMethod(owntype, sym, env, argtrees, argtypes, env.info.lastResolveVarargs(),
3739 noteWarner.hasNonSilentLint(LintCategory.UNCHECKED), resultInfo.checkContext.inferenceContext());
3740 } catch (Infer.InferenceException ex) {
3741 //invalid target type - propagate exception outwards or report error
3742 //depending on the current check context
3743 resultInfo.checkContext.report(env.tree.pos(), ex.getDiagnostic());
3744 return types.createErrorType(site);
3745 } catch (Resolve.InapplicableMethodException ex) {
3746 Assert.error(ex.getDiagnostic().getMessage(Locale.getDefault()));
3747 return null;
3748 }
3749 }
3750
3751 public void visitLiteral(JCLiteral tree) {
3752 result = check(
3753 tree, litType(tree.typetag).constType(tree.value), VAL, resultInfo);
3754 }
3755 //where
3756 /** Return the type of a literal with given type tag.
3757 */
3758 Type litType(TypeTag tag) {
3759 return (tag == CLASS) ? syms.stringType : syms.typeOfTag[tag.ordinal()];
3760 }
3761
3762 public void visitTypeIdent(JCPrimitiveTypeTree tree) {
3763 result = check(tree, syms.typeOfTag[tree.typetag.ordinal()], TYP, resultInfo);
3764 }
3765
3766 public void visitTypeArray(JCArrayTypeTree tree) {
3767 Type etype = attribType(tree.elemtype, env);
3768 Type type = new ArrayType(etype, syms.arrayClass);
3769 result = check(tree, type, TYP, resultInfo);
3770 }
3771
3772 /** Visitor method for parameterized types.
3773 * Bound checking is left until later, since types are attributed
3774 * before supertype structure is completely known
3775 */
3776 public void visitTypeApply(JCTypeApply tree) {
3777 Type owntype = types.createErrorType(tree.type);
3778
3779 // Attribute functor part of application and make sure it's a class.
3780 Type clazztype = chk.checkClassType(tree.clazz.pos(), attribType(tree.clazz, env));
3781
3782 // Attribute type parameters
3783 List<Type> actuals = attribTypes(tree.arguments, env);
3784
3785 if (clazztype.hasTag(CLASS)) {
3786 List<Type> formals = clazztype.tsym.type.getTypeArguments();
3787 if (actuals.isEmpty()) //diamond
3788 actuals = formals;
3789
3790 if (actuals.length() == formals.length()) {
3791 List<Type> a = actuals;
3792 List<Type> f = formals;
3793 while (a.nonEmpty()) {
3794 a.head = a.head.withTypeVar(f.head);
3795 a = a.tail;
3796 f = f.tail;
3797 }
3798 // Compute the proper generic outer
3799 Type clazzOuter = clazztype.getEnclosingType();
3800 if (clazzOuter.hasTag(CLASS)) {
3801 Type site;
3802 JCExpression clazz = TreeInfo.typeIn(tree.clazz);
3803 if (clazz.hasTag(IDENT)) {
3804 site = env.enclClass.sym.type;
3805 } else if (clazz.hasTag(SELECT)) {
3806 site = ((JCFieldAccess) clazz).selected.type;
3807 } else throw new AssertionError(""+tree);
3808 if (clazzOuter.hasTag(CLASS) && site != clazzOuter) {
3809 if (site.hasTag(CLASS))
3810 site = types.asOuterSuper(site, clazzOuter.tsym);
3811 if (site == null)
3812 site = types.erasure(clazzOuter);
3813 clazzOuter = site;
3814 }
3815 }
3816 owntype = new ClassType(clazzOuter, actuals, clazztype.tsym);
3817 if (clazztype.isAnnotated()) {
3818 // Use the same AnnotatedType, because it will have
3819 // its annotations set later.
3820 ((AnnotatedType)clazztype).underlyingType = owntype;
3821 owntype = clazztype;
3822 }
3823 } else {
3824 if (formals.length() != 0) {
3825 log.error(tree.pos(), "wrong.number.type.args",
3826 Integer.toString(formals.length()));
3827 } else {
3828 log.error(tree.pos(), "type.doesnt.take.params", clazztype.tsym);
3829 }
3830 owntype = types.createErrorType(tree.type);
3831 }
3832 }
3833 result = check(tree, owntype, TYP, resultInfo);
3834 }
3835
3836 public void visitTypeUnion(JCTypeUnion tree) {
3837 ListBuffer<Type> multicatchTypes = ListBuffer.lb();
3838 ListBuffer<Type> all_multicatchTypes = null; // lazy, only if needed
3839 for (JCExpression typeTree : tree.alternatives) {
3840 Type ctype = attribType(typeTree, env);
3841 ctype = chk.checkType(typeTree.pos(),
3842 chk.checkClassType(typeTree.pos(), ctype),
3843 syms.throwableType);
3844 if (!ctype.isErroneous()) {
3845 //check that alternatives of a union type are pairwise
3846 //unrelated w.r.t. subtyping
3847 if (chk.intersects(ctype, multicatchTypes.toList())) {
3848 for (Type t : multicatchTypes) {
3849 boolean sub = types.isSubtype(ctype, t);
3850 boolean sup = types.isSubtype(t, ctype);
3851 if (sub || sup) {
3852 //assume 'a' <: 'b'
3853 Type a = sub ? ctype : t;
3854 Type b = sub ? t : ctype;
3855 log.error(typeTree.pos(), "multicatch.types.must.be.disjoint", a, b);
3856 }
3857 }
3858 }
3859 multicatchTypes.append(ctype);
3860 if (all_multicatchTypes != null)
3861 all_multicatchTypes.append(ctype);
3862 } else {
3863 if (all_multicatchTypes == null) {
3864 all_multicatchTypes = ListBuffer.lb();
3865 all_multicatchTypes.appendList(multicatchTypes);
3866 }
3867 all_multicatchTypes.append(ctype);
3868 }
3869 }
3870 Type t = check(tree, types.lub(multicatchTypes.toList()), TYP, resultInfo);
3871 if (t.hasTag(CLASS)) {
3872 List<Type> alternatives =
3873 ((all_multicatchTypes == null) ? multicatchTypes : all_multicatchTypes).toList();
3874 t = new UnionClassType((ClassType) t, alternatives);
3875 }
3876 tree.type = result = t;
3877 }
3878
3879 public void visitTypeIntersection(JCTypeIntersection tree) {
3880 attribTypes(tree.bounds, env);
3881 tree.type = result = checkIntersection(tree, tree.bounds);
3882 }
3883
3884 public void visitTypeParameter(JCTypeParameter tree) {
3885 TypeVar typeVar = (TypeVar) tree.type;
3886
3887 if (tree.annotations != null && tree.annotations.nonEmpty()) {
3888 AnnotatedType antype = new AnnotatedType(typeVar);
3889 annotateType(antype, tree.annotations);
3890 tree.type = antype;
3891 }
3892
3893 if (!typeVar.bound.isErroneous()) {
3894 //fixup type-parameter bound computed in 'attribTypeVariables'
3895 typeVar.bound = checkIntersection(tree, tree.bounds);
3896 }
3897 }
3898
3899 Type checkIntersection(JCTree tree, List<JCExpression> bounds) {
3900 Set<Type> boundSet = new HashSet<Type>();
3901 if (bounds.nonEmpty()) {
3902 // accept class or interface or typevar as first bound.
3903 bounds.head.type = checkBase(bounds.head.type, bounds.head, env, false, false, false);
3904 boundSet.add(types.erasure(bounds.head.type));
3905 if (bounds.head.type.isErroneous()) {
3906 return bounds.head.type;
3907 }
3908 else if (bounds.head.type.hasTag(TYPEVAR)) {
3909 // if first bound was a typevar, do not accept further bounds.
3910 if (bounds.tail.nonEmpty()) {
3911 log.error(bounds.tail.head.pos(),
3912 "type.var.may.not.be.followed.by.other.bounds");
3913 return bounds.head.type;
3914 }
3915 } else {
3916 // if first bound was a class or interface, accept only interfaces
3917 // as further bounds.
3918 for (JCExpression bound : bounds.tail) {
3919 bound.type = checkBase(bound.type, bound, env, false, true, false);
3920 if (bound.type.isErroneous()) {
3921 bounds = List.of(bound);
3922 }
3923 else if (bound.type.hasTag(CLASS)) {
3924 chk.checkNotRepeated(bound.pos(), types.erasure(bound.type), boundSet);
3925 }
3926 }
3927 }
3928 }
3929
3930 if (bounds.length() == 0) {
3931 return syms.objectType;
3932 } else if (bounds.length() == 1) {
3933 return bounds.head.type;
3934 } else {
3935 Type owntype = types.makeCompoundType(TreeInfo.types(bounds));
3936 if (tree.hasTag(TYPEINTERSECTION)) {
3937 ((IntersectionClassType)owntype).intersectionKind =
3938 IntersectionClassType.IntersectionKind.EXPLICIT;
3939 }
3940 // ... the variable's bound is a class type flagged COMPOUND
3941 // (see comment for TypeVar.bound).
3942 // In this case, generate a class tree that represents the
3943 // bound class, ...
3944 JCExpression extending;
3945 List<JCExpression> implementing;
3946 if (!bounds.head.type.isInterface()) {
3947 extending = bounds.head;
3948 implementing = bounds.tail;
3949 } else {
3950 extending = null;
3951 implementing = bounds;
3952 }
3953 JCClassDecl cd = make.at(tree).ClassDef(
3954 make.Modifiers(PUBLIC | ABSTRACT),
3955 names.empty, List.<JCTypeParameter>nil(),
3956 extending, implementing, List.<JCTree>nil());
3957
3958 ClassSymbol c = (ClassSymbol)owntype.tsym;
3959 Assert.check((c.flags() & COMPOUND) != 0);
3960 cd.sym = c;
3961 c.sourcefile = env.toplevel.sourcefile;
3962
3963 // ... and attribute the bound class
3964 c.flags_field |= UNATTRIBUTED;
3965 Env<AttrContext> cenv = enter.classEnv(cd, env);
3966 enter.typeEnvs.put(c, cenv);
3967 attribClass(c);
3968 return owntype;
3969 }
3970 }
3971
3972 public void visitWildcard(JCWildcard tree) {
3973 //- System.err.println("visitWildcard("+tree+");");//DEBUG
3974 Type type = (tree.kind.kind == BoundKind.UNBOUND)
3975 ? syms.objectType
3976 : attribType(tree.inner, env);
3977 result = check(tree, new WildcardType(chk.checkRefType(tree.pos(), type),
3978 tree.kind.kind,
3979 syms.boundClass),
3980 TYP, resultInfo);
3981 }
3982
3983 public void visitAnnotation(JCAnnotation tree) {
3984 log.error(tree.pos(), "annotation.not.valid.for.type", pt());
3985 result = tree.type = syms.errType;
3986 }
3987
3988 public void visitAnnotatedType(JCAnnotatedType tree) {
3989 Type underlyingType = attribType(tree.getUnderlyingType(), env);
3990 this.attribAnnotationTypes(tree.annotations, env);
3991 AnnotatedType antype = new AnnotatedType(underlyingType);
3992 annotateType(antype, tree.annotations);
3993 result = tree.type = antype;
3994 }
3995
3996 /**
3997 * Apply the annotations to the particular type.
3998 */
3999 public void annotateType(final AnnotatedType type, final List<JCAnnotation> annotations) {
4000 if (annotations.isEmpty())
4001 return;
4002 annotate.typeAnnotation(new Annotate.Annotator() {
4003 @Override
4004 public String toString() {
4005 return "annotate " + annotations + " onto " + type;
4006 }
4007 @Override
4008 public void enterAnnotation() {
4009 List<Attribute.TypeCompound> compounds = fromAnnotations(annotations);
4010 type.typeAnnotations = compounds;
4011 }
4012 });
4013 }
4014
4015 private static List<Attribute.TypeCompound> fromAnnotations(List<JCAnnotation> annotations) {
4016 if (annotations.isEmpty())
4017 return List.nil();
4018
4019 ListBuffer<Attribute.TypeCompound> buf = ListBuffer.lb();
4020 for (JCAnnotation anno : annotations) {
4021 if (anno.attribute != null) {
4022 // TODO: this null-check is only needed for an obscure
4023 // ordering issue, where annotate.flush is called when
4024 // the attribute is not set yet. For an example failure
4025 // try the referenceinfos/NestedTypes.java test.
4026 // Any better solutions?
4027 buf.append((Attribute.TypeCompound) anno.attribute);
4028 }
4029 }
4030 return buf.toList();
4031 }
4032
4033 public void visitErroneous(JCErroneous tree) {
4034 if (tree.errs != null)
4035 for (JCTree err : tree.errs)
4036 attribTree(err, env, new ResultInfo(ERR, pt()));
4037 result = tree.type = syms.errType;
4038 }
4039
4040 /** Default visitor method for all other trees.
4041 */
4042 public void visitTree(JCTree tree) {
4043 throw new AssertionError();
4044 }
4045
4046 /**
4047 * Attribute an env for either a top level tree or class declaration.
4048 */
4049 public void attrib(Env<AttrContext> env) {
4050 if (env.tree.hasTag(TOPLEVEL))
4051 attribTopLevel(env);
4052 else
4053 attribClass(env.tree.pos(), env.enclClass.sym);
4054 }
4055
4056 /**
4057 * Attribute a top level tree. These trees are encountered when the
4058 * package declaration has annotations.
4059 */
4060 public void attribTopLevel(Env<AttrContext> env) {
4061 JCCompilationUnit toplevel = env.toplevel;
4062 try {
4063 annotate.flush();
4064 chk.validateAnnotations(toplevel.packageAnnotations, toplevel.packge);
4065 } catch (CompletionFailure ex) {
4066 chk.completionError(toplevel.pos(), ex);
4067 }
4068 }
4069
4070 /** Main method: attribute class definition associated with given class symbol.
4071 * reporting completion failures at the given position.
4072 * @param pos The source position at which completion errors are to be
4073 * reported.
4074 * @param c The class symbol whose definition will be attributed.
4075 */
4076 public void attribClass(DiagnosticPosition pos, ClassSymbol c) {
4077 try {
4078 annotate.flush();
4079 attribClass(c);
4080 } catch (CompletionFailure ex) {
4081 chk.completionError(pos, ex);
4082 }
4083 }
4084
4085 /** Attribute class definition associated with given class symbol.
4086 * @param c The class symbol whose definition will be attributed.
4087 */
4088 void attribClass(ClassSymbol c) throws CompletionFailure {
4089 if (c.type.hasTag(ERROR)) return;
4090
4091 // Check for cycles in the inheritance graph, which can arise from
4092 // ill-formed class files.
4093 chk.checkNonCyclic(null, c.type);
4094
4095 Type st = types.supertype(c.type);
4096 if ((c.flags_field & Flags.COMPOUND) == 0) {
4097 // First, attribute superclass.
4098 if (st.hasTag(CLASS))
4099 attribClass((ClassSymbol)st.tsym);
4100
4101 // Next attribute owner, if it is a class.
4102 if (c.owner.kind == TYP && c.owner.type.hasTag(CLASS))
4103 attribClass((ClassSymbol)c.owner);
4104 }
4105
4106 // The previous operations might have attributed the current class
4107 // if there was a cycle. So we test first whether the class is still
4108 // UNATTRIBUTED.
4109 if ((c.flags_field & UNATTRIBUTED) != 0) {
4110 c.flags_field &= ~UNATTRIBUTED;
4111
4112 // Get environment current at the point of class definition.
4113 Env<AttrContext> env = enter.typeEnvs.get(c);
4114
4115 // The info.lint field in the envs stored in enter.typeEnvs is deliberately uninitialized,
4116 // because the annotations were not available at the time the env was created. Therefore,
4117 // we look up the environment chain for the first enclosing environment for which the
4118 // lint value is set. Typically, this is the parent env, but might be further if there
4119 // are any envs created as a result of TypeParameter nodes.
4120 Env<AttrContext> lintEnv = env;
4121 while (lintEnv.info.lint == null)
4122 lintEnv = lintEnv.next;
4123
4124 // Having found the enclosing lint value, we can initialize the lint value for this class
4125 env.info.lint = lintEnv.info.lint.augment(c.annotations, c.flags());
4126
4127 Lint prevLint = chk.setLint(env.info.lint);
4128 JavaFileObject prev = log.useSource(c.sourcefile);
4129 ResultInfo prevReturnRes = env.info.returnResult;
4130
4131 try {
4132 env.info.returnResult = null;
4133 // java.lang.Enum may not be subclassed by a non-enum
4134 if (st.tsym == syms.enumSym &&
4135 ((c.flags_field & (Flags.ENUM|Flags.COMPOUND)) == 0))
4136 log.error(env.tree.pos(), "enum.no.subclassing");
4137
4138 // Enums may not be extended by source-level classes
4139 if (st.tsym != null &&
4140 ((st.tsym.flags_field & Flags.ENUM) != 0) &&
4141 ((c.flags_field & (Flags.ENUM | Flags.COMPOUND)) == 0)) {
4142 log.error(env.tree.pos(), "enum.types.not.extensible");
4143 }
4144 attribClassBody(env, c);
4145
4146 chk.checkDeprecatedAnnotation(env.tree.pos(), c);
4147 chk.checkClassOverrideEqualsAndHashIfNeeded(env.tree.pos(), c);
4148 } finally {
4149 env.info.returnResult = prevReturnRes;
4150 log.useSource(prev);
4151 chk.setLint(prevLint);
4152 }
4153
4154 }
4155 }
4156
4157 public void visitImport(JCImport tree) {
4158 // nothing to do
4159 }
4160
4161 /** Finish the attribution of a class. */
4162 private void attribClassBody(Env<AttrContext> env, ClassSymbol c) {
4163 JCClassDecl tree = (JCClassDecl)env.tree;
4164 Assert.check(c == tree.sym);
4165
4166 // Validate annotations
4167 chk.validateAnnotations(tree.mods.annotations, c);
4168
4169 // Validate type parameters, supertype and interfaces.
4170 attribStats(tree.typarams, env);
4171 if (!c.isAnonymous()) {
4172 //already checked if anonymous
4173 chk.validate(tree.typarams, env);
4174 chk.validate(tree.extending, env);
4175 chk.validate(tree.implementing, env);
4176 }
4177
4178 // If this is a non-abstract class, check that it has no abstract
4179 // methods or unimplemented methods of an implemented interface.
4180 if ((c.flags() & (ABSTRACT | INTERFACE)) == 0) {
4181 if (!relax)
4182 chk.checkAllDefined(tree.pos(), c);
4183 }
4184
4185 if ((c.flags() & ANNOTATION) != 0) {
4186 if (tree.implementing.nonEmpty())
4187 log.error(tree.implementing.head.pos(),
4188 "cant.extend.intf.annotation");
4189 if (tree.typarams.nonEmpty())
4190 log.error(tree.typarams.head.pos(),
4191 "intf.annotation.cant.have.type.params");
4192
4193 // If this annotation has a @Repeatable, validate
4194 Attribute.Compound repeatable = c.attribute(syms.repeatableType.tsym);
4195 if (repeatable != null) {
4196 // get diagnostic position for error reporting
4197 DiagnosticPosition cbPos = getDiagnosticPosition(tree, repeatable.type);
4198 Assert.checkNonNull(cbPos);
4199
4200 chk.validateRepeatable(c, repeatable, cbPos);
4201 }
4202 } else {
4203 // Check that all extended classes and interfaces
4204 // are compatible (i.e. no two define methods with same arguments
4205 // yet different return types). (JLS 8.4.6.3)
4206 chk.checkCompatibleSupertypes(tree.pos(), c.type);
4207 if (allowDefaultMethods) {
4208 chk.checkDefaultMethodClashes(tree.pos(), c.type);
4209 }
4210 }
4211
4212 // Check that class does not import the same parameterized interface
4213 // with two different argument lists.
4214 chk.checkClassBounds(tree.pos(), c.type);
4215
4216 tree.type = c.type;
4217
4218 for (List<JCTypeParameter> l = tree.typarams;
4219 l.nonEmpty(); l = l.tail) {
4220 Assert.checkNonNull(env.info.scope.lookup(l.head.name).scope);
4221 }
4222
4223 // Check that a generic class doesn't extend Throwable
4224 if (!c.type.allparams().isEmpty() && types.isSubtype(c.type, syms.throwableType))
4225 log.error(tree.extending.pos(), "generic.throwable");
4226
4227 // Check that all methods which implement some
4228 // method conform to the method they implement.
4229 chk.checkImplementations(tree);
4230
4231 //check that a resource implementing AutoCloseable cannot throw InterruptedException
4232 checkAutoCloseable(tree.pos(), env, c.type);
4233
4234 for (List<JCTree> l = tree.defs; l.nonEmpty(); l = l.tail) {
4235 // Attribute declaration
4236 attribStat(l.head, env);
4237 // Check that declarations in inner classes are not static (JLS 8.1.2)
4238 // Make an exception for static constants.
4239 if (c.owner.kind != PCK &&
4240 ((c.flags() & STATIC) == 0 || c.name == names.empty) &&
4241 (TreeInfo.flags(l.head) & (STATIC | INTERFACE)) != 0) {
4242 Symbol sym = null;
4243 if (l.head.hasTag(VARDEF)) sym = ((JCVariableDecl) l.head).sym;
4244 if (sym == null ||
4245 sym.kind != VAR ||
4246 ((VarSymbol) sym).getConstValue() == null)
4247 log.error(l.head.pos(), "icls.cant.have.static.decl", c);
4248 }
4249 }
4250
4251 // Check for cycles among non-initial constructors.
4252 chk.checkCyclicConstructors(tree);
4253
4254 // Check for cycles among annotation elements.
4255 chk.checkNonCyclicElements(tree);
4256
4257 // Check for proper use of serialVersionUID
4258 if (env.info.lint.isEnabled(LintCategory.SERIAL) &&
4259 isSerializable(c) &&
4260 (c.flags() & Flags.ENUM) == 0 &&
4261 (c.flags() & ABSTRACT) == 0) {
4262 checkSerialVersionUID(tree, c);
4263 }
4264
4265 // Correctly organize the postions of the type annotations
4266 TypeAnnotations.organizeTypeAnnotationsBodies(this.syms, this.names, this.log, tree);
4267
4268 // Check type annotations applicability rules
4269 validateTypeAnnotations(tree);
4270 }
4271 // where
4272 /** get a diagnostic position for an attribute of Type t, or null if attribute missing */
4273 private DiagnosticPosition getDiagnosticPosition(JCClassDecl tree, Type t) {
4274 for(List<JCAnnotation> al = tree.mods.annotations; !al.isEmpty(); al = al.tail) {
4275 if (types.isSameType(al.head.annotationType.type, t))
4276 return al.head.pos();
4277 }
4278
4279 return null;
4280 }
4281
4282 /** check if a class is a subtype of Serializable, if that is available. */
4283 private boolean isSerializable(ClassSymbol c) {
4284 try {
4285 syms.serializableType.complete();
4286 }
4287 catch (CompletionFailure e) {
4288 return false;
4289 }
4290 return types.isSubtype(c.type, syms.serializableType);
4291 }
4292
4293 /** Check that an appropriate serialVersionUID member is defined. */
4294 private void checkSerialVersionUID(JCClassDecl tree, ClassSymbol c) {
4295
4296 // check for presence of serialVersionUID
4297 Scope.Entry e = c.members().lookup(names.serialVersionUID);
4298 while (e.scope != null && e.sym.kind != VAR) e = e.next();
4299 if (e.scope == null) {
4300 log.warning(LintCategory.SERIAL,
4301 tree.pos(), "missing.SVUID", c);
4302 return;
4303 }
4304
4305 // check that it is static final
4306 VarSymbol svuid = (VarSymbol)e.sym;
4307 if ((svuid.flags() & (STATIC | FINAL)) !=
4308 (STATIC | FINAL))
4309 log.warning(LintCategory.SERIAL,
4310 TreeInfo.diagnosticPositionFor(svuid, tree), "improper.SVUID", c);
4311
4312 // check that it is long
4313 else if (!svuid.type.hasTag(LONG))
4314 log.warning(LintCategory.SERIAL,
4315 TreeInfo.diagnosticPositionFor(svuid, tree), "long.SVUID", c);
4316
4317 // check constant
4318 else if (svuid.getConstValue() == null)
4319 log.warning(LintCategory.SERIAL,
4320 TreeInfo.diagnosticPositionFor(svuid, tree), "constant.SVUID", c);
4321 }
4322
4323 private Type capture(Type type) {
4324 //do not capture free types
4325 return resultInfo.checkContext.inferenceContext().free(type) ?
4326 type : types.capture(type);
4327 }
4328
4329 private void validateTypeAnnotations(JCTree tree) {
4330 tree.accept(typeAnnotationsValidator);
4331 }
4332 //where
4333 private final JCTree.Visitor typeAnnotationsValidator = new TreeScanner() {
4334
4335 private boolean checkAllAnnotations = false;
4336
4337 public void visitAnnotation(JCAnnotation tree) {
4338 if (tree.hasTag(TYPE_ANNOTATION) || checkAllAnnotations) {
4339 chk.validateTypeAnnotation(tree, false);
4340 }
4341 super.visitAnnotation(tree);
4342 }
4343 public void visitTypeParameter(JCTypeParameter tree) {
4344 chk.validateTypeAnnotations(tree.annotations, true);
4345 scan(tree.bounds);
4346 // Don't call super.
4347 // This is needed because above we call validateTypeAnnotation with
4348 // false, which would forbid annotations on type parameters.
4349 // super.visitTypeParameter(tree);
4350 }
4351 public void visitMethodDef(JCMethodDecl tree) {
4352 if (tree.recvparam != null &&
4353 tree.recvparam.vartype.type.getKind() != TypeKind.ERROR) {
4354 checkForDeclarationAnnotations(tree.recvparam.mods.annotations,
4355 tree.recvparam.vartype.type.tsym);
4356 }
4357 if (tree.restype != null && tree.restype.type != null) {
4358 validateAnnotatedType(tree.restype, tree.restype.type);
4359 }
4360 super.visitMethodDef(tree);
4361 }
4362 public void visitVarDef(final JCVariableDecl tree) {
4363 if (tree.sym != null && tree.sym.type != null)
4364 validateAnnotatedType(tree, tree.sym.type);
4365 super.visitVarDef(tree);
4366 }
4367 public void visitTypeCast(JCTypeCast tree) {
4368 if (tree.clazz != null && tree.clazz.type != null)
4369 validateAnnotatedType(tree.clazz, tree.clazz.type);
4370 super.visitTypeCast(tree);
4371 }
4372 public void visitTypeTest(JCInstanceOf tree) {
4373 if (tree.clazz != null && tree.clazz.type != null)
4374 validateAnnotatedType(tree.clazz, tree.clazz.type);
4375 super.visitTypeTest(tree);
4376 }
4377 public void visitNewClass(JCNewClass tree) {
4378 if (tree.clazz.hasTag(ANNOTATED_TYPE)) {
4379 boolean prevCheck = this.checkAllAnnotations;
4380 try {
4381 this.checkAllAnnotations = true;
4382 scan(((JCAnnotatedType)tree.clazz).annotations);
4383 } finally {
4384 this.checkAllAnnotations = prevCheck;
4385 }
4386 }
4387 super.visitNewClass(tree);
4388 }
4389 public void visitNewArray(JCNewArray tree) {
4390 if (tree.elemtype != null && tree.elemtype.hasTag(ANNOTATED_TYPE)) {
4391 boolean prevCheck = this.checkAllAnnotations;
4392 try {
4393 this.checkAllAnnotations = true;
4394 scan(((JCAnnotatedType)tree.elemtype).annotations);
4395 } finally {
4396 this.checkAllAnnotations = prevCheck;
4397 }
4398 }
4399 super.visitNewArray(tree);
4400 }
4401
4402 /* I would want to model this after
4403 * com.sun.tools.javac.comp.Check.Validator.visitSelectInternal(JCFieldAccess)
4404 * and override visitSelect and visitTypeApply.
4405 * However, we only set the annotated type in the top-level type
4406 * of the symbol.
4407 * Therefore, we need to override each individual location where a type
4408 * can occur.
4409 */
4410 private void validateAnnotatedType(final JCTree errtree, final Type type) {
4411 if (type.getEnclosingType() != null &&
4412 type != type.getEnclosingType()) {
4413 validateEnclosingAnnotatedType(errtree, type.getEnclosingType());
4414 }
4415 for (Type targ : type.getTypeArguments()) {
4416 validateAnnotatedType(errtree, targ);
4417 }
4418 }
4419 private void validateEnclosingAnnotatedType(final JCTree errtree, final Type type) {
4420 validateAnnotatedType(errtree, type);
4421 if (type.tsym != null &&
4422 type.tsym.isStatic() &&
4423 type.getAnnotationMirrors().nonEmpty()) {
4424 // Enclosing static classes cannot have type annotations.
4425 log.error(errtree.pos(), "cant.annotate.static.class");
4426 }
4427 }
4428 };
4429
4430 // <editor-fold desc="post-attribution visitor">
4431
4432 /**
4433 * Handle missing types/symbols in an AST. This routine is useful when
4434 * the compiler has encountered some errors (which might have ended up
4435 * terminating attribution abruptly); if the compiler is used in fail-over
4436 * mode (e.g. by an IDE) and the AST contains semantic errors, this routine
4437 * prevents NPE to be progagated during subsequent compilation steps.
4438 */
4439 public void postAttr(JCTree tree) {
4440 new PostAttrAnalyzer().scan(tree);
4441 }
4442
4443 class PostAttrAnalyzer extends TreeScanner {
4444
4445 private void initTypeIfNeeded(JCTree that) {
4446 if (that.type == null) {
4447 that.type = syms.unknownType;
4448 }
4449 }
4450
4451 @Override
4452 public void scan(JCTree tree) {
4453 if (tree == null) return;
4454 if (tree instanceof JCExpression) {
4455 initTypeIfNeeded(tree);
4456 }
4457 super.scan(tree);
4458 }
4459
4460 @Override
4461 public void visitIdent(JCIdent that) {
4462 if (that.sym == null) {
4463 that.sym = syms.unknownSymbol;
4464 }
4465 }
4466
4467 @Override
4468 public void visitSelect(JCFieldAccess that) {
4469 if (that.sym == null) {
4470 that.sym = syms.unknownSymbol;
4471 }
4472 super.visitSelect(that);
4473 }
4474
4475 @Override
4476 public void visitClassDef(JCClassDecl that) {
4477 initTypeIfNeeded(that);
4478 if (that.sym == null) {
4479 that.sym = new ClassSymbol(0, that.name, that.type, syms.noSymbol);
4480 }
4481 super.visitClassDef(that);
4482 }
4483
4484 @Override
4485 public void visitMethodDef(JCMethodDecl that) {
4486 initTypeIfNeeded(that);
4487 if (that.sym == null) {
4488 that.sym = new MethodSymbol(0, that.name, that.type, syms.noSymbol);
4489 }
4490 super.visitMethodDef(that);
4491 }
4492
4493 @Override
4494 public void visitVarDef(JCVariableDecl that) {
4495 initTypeIfNeeded(that);
4496 if (that.sym == null) {
4497 that.sym = new VarSymbol(0, that.name, that.type, syms.noSymbol);
4498 that.sym.adr = 0;
4499 }
4500 super.visitVarDef(that);
4501 }
4502
4503 @Override
4504 public void visitNewClass(JCNewClass that) {
4505 if (that.constructor == null) {
4506 that.constructor = new MethodSymbol(0, names.init, syms.unknownType, syms.noSymbol);
4507 }
4508 if (that.constructorType == null) {
4509 that.constructorType = syms.unknownType;
4510 }
4511 super.visitNewClass(that);
4512 }
4513
4514 @Override
4515 public void visitAssignop(JCAssignOp that) {
4516 if (that.operator == null)
4517 that.operator = new OperatorSymbol(names.empty, syms.unknownType, -1, syms.noSymbol);
4518 super.visitAssignop(that);
4519 }
4520
4521 @Override
4522 public void visitBinary(JCBinary that) {
4523 if (that.operator == null)
4524 that.operator = new OperatorSymbol(names.empty, syms.unknownType, -1, syms.noSymbol);
4525 super.visitBinary(that);
4526 }
4527
4528 @Override
4529 public void visitUnary(JCUnary that) {
4530 if (that.operator == null)
4531 that.operator = new OperatorSymbol(names.empty, syms.unknownType, -1, syms.noSymbol);
4532 super.visitUnary(that);
4533 }
4534
4535 @Override
4536 public void visitLambda(JCLambda that) {
4537 super.visitLambda(that);
4538 if (that.descriptorType == null) {
4539 that.descriptorType = syms.unknownType;
4540 }
4541 if (that.targets == null) {
4542 that.targets = List.nil();
4543 }
4544 }
4545
4546 @Override
4547 public void visitReference(JCMemberReference that) {
4548 super.visitReference(that);
4549 if (that.sym == null) {
4550 that.sym = new MethodSymbol(0, names.empty, syms.unknownType, syms.noSymbol);
4551 }
4552 if (that.descriptorType == null) {
4553 that.descriptorType = syms.unknownType;
4554 }
4555 if (that.targets == null) {
4556 that.targets = List.nil();
4557 }
4558 }
4559 }
4560 // </editor-fold>
4561 }