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src/share/classes/com/sun/tools/javac/comp/Attr.java@4f9853659bf1
src/share/classes/com/sun/tools/javac/comp/Attr.java
Fri, 30 Nov 2012 15:14:12 +0000
- author
- mcimadamore
- date
- Fri, 30 Nov 2012 15:14:12 +0000
- changeset 1433
- 4f9853659bf1
- parent 1415
- 01c9d4161882
- child 1434
- 34d1ebaf4645
- permissions
- -rw-r--r--
8004105: Expression statement lambdas should be void-compatible
Summary: Fix lambda compatibility rules as per latest EDR
Reviewed-by: jjg
1 /*
2 * Copyright (c) 1999, 2012, 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 */
26 package com.sun.tools.javac.comp;
28 import java.util.*;
29 import java.util.Set;
31 import javax.lang.model.element.ElementKind;
32 import javax.tools.JavaFileObject;
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.InferenceContext.FreeTypeListener;
47 import com.sun.tools.javac.jvm.*;
48 import com.sun.tools.javac.jvm.Target;
49 import com.sun.tools.javac.tree.*;
50 import com.sun.tools.javac.tree.JCTree.*;
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.*;
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>();
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;
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 }
105 protected Attr(Context context) {
106 context.put(attrKey, this);
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);
126 Options options = Options.instance(context);
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);
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 recoveryInfo = new RecoveryInfo(deferredAttr.emptyDeferredAttrContext);
152 }
154 /** Switch: relax some constraints for retrofit mode.
155 */
156 boolean relax;
158 /** Switch: support target-typing inference
159 */
160 boolean allowPoly;
162 /** Switch: support generics?
163 */
164 boolean allowGenerics;
166 /** Switch: allow variable-arity methods.
167 */
168 boolean allowVarargs;
170 /** Switch: support enums?
171 */
172 boolean allowEnums;
174 /** Switch: support boxing and unboxing?
175 */
176 boolean allowBoxing;
178 /** Switch: support covariant result types?
179 */
180 boolean allowCovariantReturns;
182 /** Switch: support lambda expressions ?
183 */
184 boolean allowLambda;
186 /** Switch: support default methods ?
187 */
188 boolean allowDefaultMethods;
190 /** Switch: allow references to surrounding object from anonymous
191 * objects during constructor call?
192 */
193 boolean allowAnonOuterThis;
195 /** Switch: generates a warning if diamond can be safely applied
196 * to a given new expression
197 */
198 boolean findDiamonds;
200 /**
201 * Internally enables/disables diamond finder feature
202 */
203 static final boolean allowDiamondFinder = true;
205 /**
206 * Switch: warn about use of variable before declaration?
207 * RFE: 6425594
208 */
209 boolean useBeforeDeclarationWarning;
211 /**
212 * Switch: generate warnings whenever an anonymous inner class that is convertible
213 * to a lambda expression is found
214 */
215 boolean identifyLambdaCandidate;
217 /**
218 * Switch: allow strings in switch?
219 */
220 boolean allowStringsInSwitch;
222 /**
223 * Switch: name of source level; used for error reporting.
224 */
225 String sourceName;
227 /** Check kind and type of given tree against protokind and prototype.
228 * If check succeeds, store type in tree and return it.
229 * If check fails, store errType in tree and return it.
230 * No checks are performed if the prototype is a method type.
231 * It is not necessary in this case since we know that kind and type
232 * are correct.
233 *
234 * @param tree The tree whose kind and type is checked
235 * @param ownkind The computed kind of the tree
236 * @param resultInfo The expected result of the tree
237 */
238 Type check(final JCTree tree, final Type found, final int ownkind, final ResultInfo resultInfo) {
239 InferenceContext inferenceContext = resultInfo.checkContext.inferenceContext();
240 Type owntype = found;
241 if (!owntype.hasTag(ERROR) && !resultInfo.pt.hasTag(METHOD) && !resultInfo.pt.hasTag(FORALL)) {
242 if (inferenceContext.free(found)) {
243 inferenceContext.addFreeTypeListener(List.of(found, resultInfo.pt), new FreeTypeListener() {
244 @Override
245 public void typesInferred(InferenceContext inferenceContext) {
246 ResultInfo pendingResult =
247 resultInfo.dup(inferenceContext.asInstType(resultInfo.pt, types));
248 check(tree, inferenceContext.asInstType(found, types), ownkind, pendingResult);
249 }
250 });
251 return tree.type = resultInfo.pt;
252 } else {
253 if ((ownkind & ~resultInfo.pkind) == 0) {
254 owntype = resultInfo.check(tree, owntype);
255 } else {
256 log.error(tree.pos(), "unexpected.type",
257 kindNames(resultInfo.pkind),
258 kindName(ownkind));
259 owntype = types.createErrorType(owntype);
260 }
261 }
262 }
263 tree.type = owntype;
264 return owntype;
265 }
267 /** Is given blank final variable assignable, i.e. in a scope where it
268 * may be assigned to even though it is final?
269 * @param v The blank final variable.
270 * @param env The current environment.
271 */
272 boolean isAssignableAsBlankFinal(VarSymbol v, Env<AttrContext> env) {
273 Symbol owner = owner(env);
274 // owner refers to the innermost variable, method or
275 // initializer block declaration at this point.
276 return
277 v.owner == owner
278 ||
279 ((owner.name == names.init || // i.e. we are in a constructor
280 owner.kind == VAR || // i.e. we are in a variable initializer
281 (owner.flags() & BLOCK) != 0) // i.e. we are in an initializer block
282 &&
283 v.owner == owner.owner
284 &&
285 ((v.flags() & STATIC) != 0) == Resolve.isStatic(env));
286 }
288 /**
289 * Return the innermost enclosing owner symbol in a given attribution context
290 */
291 Symbol owner(Env<AttrContext> env) {
292 while (true) {
293 switch (env.tree.getTag()) {
294 case VARDEF:
295 //a field can be owner
296 VarSymbol vsym = ((JCVariableDecl)env.tree).sym;
297 if (vsym.owner.kind == TYP) {
298 return vsym;
299 }
300 break;
301 case METHODDEF:
302 //method def is always an owner
303 return ((JCMethodDecl)env.tree).sym;
304 case CLASSDEF:
305 //class def is always an owner
306 return ((JCClassDecl)env.tree).sym;
307 case LAMBDA:
308 //a lambda is an owner - return a fresh synthetic method symbol
309 return new MethodSymbol(0, names.empty, null, syms.methodClass);
310 case BLOCK:
311 //static/instance init blocks are owner
312 Symbol blockSym = env.info.scope.owner;
313 if ((blockSym.flags() & BLOCK) != 0) {
314 return blockSym;
315 }
316 break;
317 case TOPLEVEL:
318 //toplevel is always an owner (for pkge decls)
319 return env.info.scope.owner;
320 }
321 Assert.checkNonNull(env.next);
322 env = env.next;
323 }
324 }
326 /** Check that variable can be assigned to.
327 * @param pos The current source code position.
328 * @param v The assigned varaible
329 * @param base If the variable is referred to in a Select, the part
330 * to the left of the `.', null otherwise.
331 * @param env The current environment.
332 */
333 void checkAssignable(DiagnosticPosition pos, VarSymbol v, JCTree base, Env<AttrContext> env) {
334 if ((v.flags() & FINAL) != 0 &&
335 ((v.flags() & HASINIT) != 0
336 ||
337 !((base == null ||
338 (base.hasTag(IDENT) && TreeInfo.name(base) == names._this)) &&
339 isAssignableAsBlankFinal(v, env)))) {
340 if (v.isResourceVariable()) { //TWR resource
341 log.error(pos, "try.resource.may.not.be.assigned", v);
342 } else {
343 log.error(pos, "cant.assign.val.to.final.var", v);
344 }
345 }
346 }
348 /** Does tree represent a static reference to an identifier?
349 * It is assumed that tree is either a SELECT or an IDENT.
350 * We have to weed out selects from non-type names here.
351 * @param tree The candidate tree.
352 */
353 boolean isStaticReference(JCTree tree) {
354 if (tree.hasTag(SELECT)) {
355 Symbol lsym = TreeInfo.symbol(((JCFieldAccess) tree).selected);
356 if (lsym == null || lsym.kind != TYP) {
357 return false;
358 }
359 }
360 return true;
361 }
363 /** Is this symbol a type?
364 */
365 static boolean isType(Symbol sym) {
366 return sym != null && sym.kind == TYP;
367 }
369 /** The current `this' symbol.
370 * @param env The current environment.
371 */
372 Symbol thisSym(DiagnosticPosition pos, Env<AttrContext> env) {
373 return rs.resolveSelf(pos, env, env.enclClass.sym, names._this);
374 }
376 /** Attribute a parsed identifier.
377 * @param tree Parsed identifier name
378 * @param topLevel The toplevel to use
379 */
380 public Symbol attribIdent(JCTree tree, JCCompilationUnit topLevel) {
381 Env<AttrContext> localEnv = enter.topLevelEnv(topLevel);
382 localEnv.enclClass = make.ClassDef(make.Modifiers(0),
383 syms.errSymbol.name,
384 null, null, null, null);
385 localEnv.enclClass.sym = syms.errSymbol;
386 return tree.accept(identAttributer, localEnv);
387 }
388 // where
389 private TreeVisitor<Symbol,Env<AttrContext>> identAttributer = new IdentAttributer();
390 private class IdentAttributer extends SimpleTreeVisitor<Symbol,Env<AttrContext>> {
391 @Override
392 public Symbol visitMemberSelect(MemberSelectTree node, Env<AttrContext> env) {
393 Symbol site = visit(node.getExpression(), env);
394 if (site.kind == ERR)
395 return site;
396 Name name = (Name)node.getIdentifier();
397 if (site.kind == PCK) {
398 env.toplevel.packge = (PackageSymbol)site;
399 return rs.findIdentInPackage(env, (TypeSymbol)site, name, TYP | PCK);
400 } else {
401 env.enclClass.sym = (ClassSymbol)site;
402 return rs.findMemberType(env, site.asType(), name, (TypeSymbol)site);
403 }
404 }
406 @Override
407 public Symbol visitIdentifier(IdentifierTree node, Env<AttrContext> env) {
408 return rs.findIdent(env, (Name)node.getName(), TYP | PCK);
409 }
410 }
412 public Type coerce(Type etype, Type ttype) {
413 return cfolder.coerce(etype, ttype);
414 }
416 public Type attribType(JCTree node, TypeSymbol sym) {
417 Env<AttrContext> env = enter.typeEnvs.get(sym);
418 Env<AttrContext> localEnv = env.dup(node, env.info.dup());
419 return attribTree(node, localEnv, unknownTypeInfo);
420 }
422 public Type attribImportQualifier(JCImport tree, Env<AttrContext> env) {
423 // Attribute qualifying package or class.
424 JCFieldAccess s = (JCFieldAccess)tree.qualid;
425 return attribTree(s.selected,
426 env,
427 new ResultInfo(tree.staticImport ? TYP : (TYP | PCK),
428 Type.noType));
429 }
431 public Env<AttrContext> attribExprToTree(JCTree expr, Env<AttrContext> env, JCTree tree) {
432 breakTree = tree;
433 JavaFileObject prev = log.useSource(env.toplevel.sourcefile);
434 try {
435 attribExpr(expr, env);
436 } catch (BreakAttr b) {
437 return b.env;
438 } catch (AssertionError ae) {
439 if (ae.getCause() instanceof BreakAttr) {
440 return ((BreakAttr)(ae.getCause())).env;
441 } else {
442 throw ae;
443 }
444 } finally {
445 breakTree = null;
446 log.useSource(prev);
447 }
448 return env;
449 }
451 public Env<AttrContext> attribStatToTree(JCTree stmt, Env<AttrContext> env, JCTree tree) {
452 breakTree = tree;
453 JavaFileObject prev = log.useSource(env.toplevel.sourcefile);
454 try {
455 attribStat(stmt, env);
456 } catch (BreakAttr b) {
457 return b.env;
458 } catch (AssertionError ae) {
459 if (ae.getCause() instanceof BreakAttr) {
460 return ((BreakAttr)(ae.getCause())).env;
461 } else {
462 throw ae;
463 }
464 } finally {
465 breakTree = null;
466 log.useSource(prev);
467 }
468 return env;
469 }
471 private JCTree breakTree = null;
473 private static class BreakAttr extends RuntimeException {
474 static final long serialVersionUID = -6924771130405446405L;
475 private Env<AttrContext> env;
476 private BreakAttr(Env<AttrContext> env) {
477 this.env = copyEnv(env);
478 }
480 private Env<AttrContext> copyEnv(Env<AttrContext> env) {
481 Env<AttrContext> newEnv =
482 env.dup(env.tree, env.info.dup(copyScope(env.info.scope)));
483 if (newEnv.outer != null) {
484 newEnv.outer = copyEnv(newEnv.outer);
485 }
486 return newEnv;
487 }
489 private Scope copyScope(Scope sc) {
490 Scope newScope = new Scope(sc.owner);
491 List<Symbol> elemsList = List.nil();
492 while (sc != null) {
493 for (Scope.Entry e = sc.elems ; e != null ; e = e.sibling) {
494 elemsList = elemsList.prepend(e.sym);
495 }
496 sc = sc.next;
497 }
498 for (Symbol s : elemsList) {
499 newScope.enter(s);
500 }
501 return newScope;
502 }
503 }
505 class ResultInfo {
506 final int pkind;
507 final Type pt;
508 final CheckContext checkContext;
510 ResultInfo(int pkind, Type pt) {
511 this(pkind, pt, chk.basicHandler);
512 }
514 protected ResultInfo(int pkind, Type pt, CheckContext checkContext) {
515 this.pkind = pkind;
516 this.pt = pt;
517 this.checkContext = checkContext;
518 }
520 protected Type check(final DiagnosticPosition pos, final Type found) {
521 return chk.checkType(pos, found, pt, checkContext);
522 }
524 protected ResultInfo dup(Type newPt) {
525 return new ResultInfo(pkind, newPt, checkContext);
526 }
528 protected ResultInfo dup(CheckContext newContext) {
529 return new ResultInfo(pkind, pt, newContext);
530 }
531 }
533 class RecoveryInfo extends ResultInfo {
535 public RecoveryInfo(final DeferredAttr.DeferredAttrContext deferredAttrContext) {
536 super(Kinds.VAL, Type.recoveryType, new Check.NestedCheckContext(chk.basicHandler) {
537 @Override
538 public DeferredAttr.DeferredAttrContext deferredAttrContext() {
539 return deferredAttrContext;
540 }
541 @Override
542 public boolean compatible(Type found, Type req, Warner warn) {
543 return true;
544 }
545 @Override
546 public void report(DiagnosticPosition pos, JCDiagnostic details) {
547 chk.basicHandler.report(pos, details);
548 }
549 });
550 }
552 @Override
553 protected Type check(DiagnosticPosition pos, Type found) {
554 return chk.checkNonVoid(pos, super.check(pos, found));
555 }
556 }
558 final ResultInfo statInfo;
559 final ResultInfo varInfo;
560 final ResultInfo unknownExprInfo;
561 final ResultInfo unknownTypeInfo;
562 final ResultInfo recoveryInfo;
564 Type pt() {
565 return resultInfo.pt;
566 }
568 int pkind() {
569 return resultInfo.pkind;
570 }
572 /* ************************************************************************
573 * Visitor methods
574 *************************************************************************/
576 /** Visitor argument: the current environment.
577 */
578 Env<AttrContext> env;
580 /** Visitor argument: the currently expected attribution result.
581 */
582 ResultInfo resultInfo;
584 /** Visitor result: the computed type.
585 */
586 Type result;
588 /** Visitor method: attribute a tree, catching any completion failure
589 * exceptions. Return the tree's type.
590 *
591 * @param tree The tree to be visited.
592 * @param env The environment visitor argument.
593 * @param resultInfo The result info visitor argument.
594 */
595 Type attribTree(JCTree tree, Env<AttrContext> env, ResultInfo resultInfo) {
596 Env<AttrContext> prevEnv = this.env;
597 ResultInfo prevResult = this.resultInfo;
598 try {
599 this.env = env;
600 this.resultInfo = resultInfo;
601 tree.accept(this);
602 if (tree == breakTree &&
603 resultInfo.checkContext.deferredAttrContext().mode == AttrMode.CHECK) {
604 throw new BreakAttr(env);
605 }
606 return result;
607 } catch (CompletionFailure ex) {
608 tree.type = syms.errType;
609 return chk.completionError(tree.pos(), ex);
610 } finally {
611 this.env = prevEnv;
612 this.resultInfo = prevResult;
613 }
614 }
616 /** Derived visitor method: attribute an expression tree.
617 */
618 public Type attribExpr(JCTree tree, Env<AttrContext> env, Type pt) {
619 return attribTree(tree, env, new ResultInfo(VAL, !pt.hasTag(ERROR) ? pt : Type.noType));
620 }
622 /** Derived visitor method: attribute an expression tree with
623 * no constraints on the computed type.
624 */
625 public Type attribExpr(JCTree tree, Env<AttrContext> env) {
626 return attribTree(tree, env, unknownExprInfo);
627 }
629 /** Derived visitor method: attribute a type tree.
630 */
631 public Type attribType(JCTree tree, Env<AttrContext> env) {
632 Type result = attribType(tree, env, Type.noType);
633 return result;
634 }
636 /** Derived visitor method: attribute a type tree.
637 */
638 Type attribType(JCTree tree, Env<AttrContext> env, Type pt) {
639 Type result = attribTree(tree, env, new ResultInfo(TYP, pt));
640 return result;
641 }
643 /** Derived visitor method: attribute a statement or definition tree.
644 */
645 public Type attribStat(JCTree tree, Env<AttrContext> env) {
646 return attribTree(tree, env, statInfo);
647 }
649 /** Attribute a list of expressions, returning a list of types.
650 */
651 List<Type> attribExprs(List<JCExpression> trees, Env<AttrContext> env, Type pt) {
652 ListBuffer<Type> ts = new ListBuffer<Type>();
653 for (List<JCExpression> l = trees; l.nonEmpty(); l = l.tail)
654 ts.append(attribExpr(l.head, env, pt));
655 return ts.toList();
656 }
658 /** Attribute a list of statements, returning nothing.
659 */
660 <T extends JCTree> void attribStats(List<T> trees, Env<AttrContext> env) {
661 for (List<T> l = trees; l.nonEmpty(); l = l.tail)
662 attribStat(l.head, env);
663 }
665 /** Attribute the arguments in a method call, returning a list of types.
666 */
667 List<Type> attribArgs(List<JCExpression> trees, Env<AttrContext> env) {
668 ListBuffer<Type> argtypes = new ListBuffer<Type>();
669 for (JCExpression arg : trees) {
670 Type argtype = allowPoly && TreeInfo.isPoly(arg, env.tree) ?
671 deferredAttr.new DeferredType(arg, env) :
672 chk.checkNonVoid(arg, attribExpr(arg, env, Infer.anyPoly));
673 argtypes.append(argtype);
674 }
675 return argtypes.toList();
676 }
678 /** Attribute a type argument list, returning a list of types.
679 * Caller is responsible for calling checkRefTypes.
680 */
681 List<Type> attribAnyTypes(List<JCExpression> trees, Env<AttrContext> env) {
682 ListBuffer<Type> argtypes = new ListBuffer<Type>();
683 for (List<JCExpression> l = trees; l.nonEmpty(); l = l.tail)
684 argtypes.append(attribType(l.head, env));
685 return argtypes.toList();
686 }
688 /** Attribute a type argument list, returning a list of types.
689 * Check that all the types are references.
690 */
691 List<Type> attribTypes(List<JCExpression> trees, Env<AttrContext> env) {
692 List<Type> types = attribAnyTypes(trees, env);
693 return chk.checkRefTypes(trees, types);
694 }
696 /**
697 * Attribute type variables (of generic classes or methods).
698 * Compound types are attributed later in attribBounds.
699 * @param typarams the type variables to enter
700 * @param env the current environment
701 */
702 void attribTypeVariables(List<JCTypeParameter> typarams, Env<AttrContext> env) {
703 for (JCTypeParameter tvar : typarams) {
704 TypeVar a = (TypeVar)tvar.type;
705 a.tsym.flags_field |= UNATTRIBUTED;
706 a.bound = Type.noType;
707 if (!tvar.bounds.isEmpty()) {
708 List<Type> bounds = List.of(attribType(tvar.bounds.head, env));
709 for (JCExpression bound : tvar.bounds.tail)
710 bounds = bounds.prepend(attribType(bound, env));
711 types.setBounds(a, bounds.reverse());
712 } else {
713 // if no bounds are given, assume a single bound of
714 // java.lang.Object.
715 types.setBounds(a, List.of(syms.objectType));
716 }
717 a.tsym.flags_field &= ~UNATTRIBUTED;
718 }
719 for (JCTypeParameter tvar : typarams)
720 chk.checkNonCyclic(tvar.pos(), (TypeVar)tvar.type);
721 attribStats(typarams, env);
722 }
724 void attribBounds(List<JCTypeParameter> typarams) {
725 for (JCTypeParameter typaram : typarams) {
726 Type bound = typaram.type.getUpperBound();
727 if (bound != null && bound.tsym instanceof ClassSymbol) {
728 ClassSymbol c = (ClassSymbol)bound.tsym;
729 if ((c.flags_field & COMPOUND) != 0) {
730 Assert.check((c.flags_field & UNATTRIBUTED) != 0, c);
731 attribClass(typaram.pos(), c);
732 }
733 }
734 }
735 }
737 /**
738 * Attribute the type references in a list of annotations.
739 */
740 void attribAnnotationTypes(List<JCAnnotation> annotations,
741 Env<AttrContext> env) {
742 for (List<JCAnnotation> al = annotations; al.nonEmpty(); al = al.tail) {
743 JCAnnotation a = al.head;
744 attribType(a.annotationType, env);
745 }
746 }
748 /**
749 * Attribute a "lazy constant value".
750 * @param env The env for the const value
751 * @param initializer The initializer for the const value
752 * @param type The expected type, or null
753 * @see VarSymbol#setLazyConstValue
754 */
755 public Object attribLazyConstantValue(Env<AttrContext> env,
756 JCTree.JCExpression initializer,
757 Type type) {
759 // in case no lint value has been set up for this env, scan up
760 // env stack looking for smallest enclosing env for which it is set.
761 Env<AttrContext> lintEnv = env;
762 while (lintEnv.info.lint == null)
763 lintEnv = lintEnv.next;
765 // Having found the enclosing lint value, we can initialize the lint value for this class
766 // ... but ...
767 // There's a problem with evaluating annotations in the right order, such that
768 // env.info.enclVar.attributes_field might not yet have been evaluated, and so might be
769 // null. In that case, calling augment will throw an NPE. To avoid this, for now we
770 // revert to the jdk 6 behavior and ignore the (unevaluated) attributes.
771 if (env.info.enclVar.annotations.pendingCompletion()) {
772 env.info.lint = lintEnv.info.lint;
773 } else {
774 env.info.lint = lintEnv.info.lint.augment(env.info.enclVar.annotations,
775 env.info.enclVar.flags());
776 }
778 Lint prevLint = chk.setLint(env.info.lint);
779 JavaFileObject prevSource = log.useSource(env.toplevel.sourcefile);
781 try {
782 Type itype = attribExpr(initializer, env, type);
783 if (itype.constValue() != null)
784 return coerce(itype, type).constValue();
785 else
786 return null;
787 } finally {
788 env.info.lint = prevLint;
789 log.useSource(prevSource);
790 }
791 }
793 /** Attribute type reference in an `extends' or `implements' clause.
794 * Supertypes of anonymous inner classes are usually already attributed.
795 *
796 * @param tree The tree making up the type reference.
797 * @param env The environment current at the reference.
798 * @param classExpected true if only a class is expected here.
799 * @param interfaceExpected true if only an interface is expected here.
800 */
801 Type attribBase(JCTree tree,
802 Env<AttrContext> env,
803 boolean classExpected,
804 boolean interfaceExpected,
805 boolean checkExtensible) {
806 Type t = tree.type != null ?
807 tree.type :
808 attribType(tree, env);
809 return checkBase(t, tree, env, classExpected, interfaceExpected, checkExtensible);
810 }
811 Type checkBase(Type t,
812 JCTree tree,
813 Env<AttrContext> env,
814 boolean classExpected,
815 boolean interfaceExpected,
816 boolean checkExtensible) {
817 if (t.isErroneous())
818 return t;
819 if (t.hasTag(TYPEVAR) && !classExpected && !interfaceExpected) {
820 // check that type variable is already visible
821 if (t.getUpperBound() == null) {
822 log.error(tree.pos(), "illegal.forward.ref");
823 return types.createErrorType(t);
824 }
825 } else {
826 t = chk.checkClassType(tree.pos(), t, checkExtensible|!allowGenerics);
827 }
828 if (interfaceExpected && (t.tsym.flags() & INTERFACE) == 0) {
829 log.error(tree.pos(), "intf.expected.here");
830 // return errType is necessary since otherwise there might
831 // be undetected cycles which cause attribution to loop
832 return types.createErrorType(t);
833 } else if (checkExtensible &&
834 classExpected &&
835 (t.tsym.flags() & INTERFACE) != 0) {
836 log.error(tree.pos(), "no.intf.expected.here");
837 return types.createErrorType(t);
838 }
839 if (checkExtensible &&
840 ((t.tsym.flags() & FINAL) != 0)) {
841 log.error(tree.pos(),
842 "cant.inherit.from.final", t.tsym);
843 }
844 chk.checkNonCyclic(tree.pos(), t);
845 return t;
846 }
848 Type attribIdentAsEnumType(Env<AttrContext> env, JCIdent id) {
849 Assert.check((env.enclClass.sym.flags() & ENUM) != 0);
850 id.type = env.info.scope.owner.type;
851 id.sym = env.info.scope.owner;
852 return id.type;
853 }
855 public void visitClassDef(JCClassDecl tree) {
856 // Local classes have not been entered yet, so we need to do it now:
857 if ((env.info.scope.owner.kind & (VAR | MTH)) != 0)
858 enter.classEnter(tree, env);
860 ClassSymbol c = tree.sym;
861 if (c == null) {
862 // exit in case something drastic went wrong during enter.
863 result = null;
864 } else {
865 // make sure class has been completed:
866 c.complete();
868 // If this class appears as an anonymous class
869 // in a superclass constructor call where
870 // no explicit outer instance is given,
871 // disable implicit outer instance from being passed.
872 // (This would be an illegal access to "this before super").
873 if (env.info.isSelfCall &&
874 env.tree.hasTag(NEWCLASS) &&
875 ((JCNewClass) env.tree).encl == null)
876 {
877 c.flags_field |= NOOUTERTHIS;
878 }
879 attribClass(tree.pos(), c);
880 result = tree.type = c.type;
881 }
882 }
884 public void visitMethodDef(JCMethodDecl tree) {
885 MethodSymbol m = tree.sym;
886 boolean isDefaultMethod = (m.flags() & DEFAULT) != 0;
888 Lint lint = env.info.lint.augment(m.annotations, m.flags());
889 Lint prevLint = chk.setLint(lint);
890 MethodSymbol prevMethod = chk.setMethod(m);
891 try {
892 deferredLintHandler.flush(tree.pos());
893 chk.checkDeprecatedAnnotation(tree.pos(), m);
895 attribBounds(tree.typarams);
897 // If we override any other methods, check that we do so properly.
898 // JLS ???
899 if (m.isStatic()) {
900 chk.checkHideClashes(tree.pos(), env.enclClass.type, m);
901 } else {
902 chk.checkOverrideClashes(tree.pos(), env.enclClass.type, m);
903 }
904 chk.checkOverride(tree, m);
906 // Create a new environment with local scope
907 // for attributing the method.
908 Env<AttrContext> localEnv = memberEnter.methodEnv(tree, env);
910 localEnv.info.lint = lint;
912 if (isDefaultMethod && types.overridesObjectMethod(m.enclClass(), m)) {
913 log.error(tree, "default.overrides.object.member", m.name, Kinds.kindName(m.location()), m.location());
914 }
916 // Enter all type parameters into the local method scope.
917 for (List<JCTypeParameter> l = tree.typarams; l.nonEmpty(); l = l.tail)
918 localEnv.info.scope.enterIfAbsent(l.head.type.tsym);
920 ClassSymbol owner = env.enclClass.sym;
921 if ((owner.flags() & ANNOTATION) != 0 &&
922 tree.params.nonEmpty())
923 log.error(tree.params.head.pos(),
924 "intf.annotation.members.cant.have.params");
926 // Attribute all value parameters.
927 for (List<JCVariableDecl> l = tree.params; l.nonEmpty(); l = l.tail) {
928 attribStat(l.head, localEnv);
929 }
931 chk.checkVarargsMethodDecl(localEnv, tree);
933 // Check that type parameters are well-formed.
934 chk.validate(tree.typarams, localEnv);
936 // Check that result type is well-formed.
937 chk.validate(tree.restype, localEnv);
939 // annotation method checks
940 if ((owner.flags() & ANNOTATION) != 0) {
941 // annotation method cannot have throws clause
942 if (tree.thrown.nonEmpty()) {
943 log.error(tree.thrown.head.pos(),
944 "throws.not.allowed.in.intf.annotation");
945 }
946 // annotation method cannot declare type-parameters
947 if (tree.typarams.nonEmpty()) {
948 log.error(tree.typarams.head.pos(),
949 "intf.annotation.members.cant.have.type.params");
950 }
951 // validate annotation method's return type (could be an annotation type)
952 chk.validateAnnotationType(tree.restype);
953 // ensure that annotation method does not clash with members of Object/Annotation
954 chk.validateAnnotationMethod(tree.pos(), m);
956 if (tree.defaultValue != null) {
957 // if default value is an annotation, check it is a well-formed
958 // annotation value (e.g. no duplicate values, no missing values, etc.)
959 chk.validateAnnotationTree(tree.defaultValue);
960 }
961 }
963 for (List<JCExpression> l = tree.thrown; l.nonEmpty(); l = l.tail)
964 chk.checkType(l.head.pos(), l.head.type, syms.throwableType);
966 if (tree.body == null) {
967 // Empty bodies are only allowed for
968 // abstract, native, or interface methods, or for methods
969 // in a retrofit signature class.
970 if (isDefaultMethod || ((owner.flags() & INTERFACE) == 0 &&
971 (tree.mods.flags & (ABSTRACT | NATIVE)) == 0) &&
972 !relax)
973 log.error(tree.pos(), "missing.meth.body.or.decl.abstract");
974 if (tree.defaultValue != null) {
975 if ((owner.flags() & ANNOTATION) == 0)
976 log.error(tree.pos(),
977 "default.allowed.in.intf.annotation.member");
978 }
979 } else if ((tree.sym.flags() & ABSTRACT) != 0 && !isDefaultMethod) {
980 if ((owner.flags() & INTERFACE) != 0) {
981 log.error(tree.body.pos(), "intf.meth.cant.have.body");
982 } else {
983 log.error(tree.pos(), "abstract.meth.cant.have.body");
984 }
985 } else if ((tree.mods.flags & NATIVE) != 0) {
986 log.error(tree.pos(), "native.meth.cant.have.body");
987 } else {
988 // Add an implicit super() call unless an explicit call to
989 // super(...) or this(...) is given
990 // or we are compiling class java.lang.Object.
991 if (tree.name == names.init && owner.type != syms.objectType) {
992 JCBlock body = tree.body;
993 if (body.stats.isEmpty() ||
994 !TreeInfo.isSelfCall(body.stats.head)) {
995 body.stats = body.stats.
996 prepend(memberEnter.SuperCall(make.at(body.pos),
997 List.<Type>nil(),
998 List.<JCVariableDecl>nil(),
999 false));
1000 } else if ((env.enclClass.sym.flags() & ENUM) != 0 &&
1001 (tree.mods.flags & GENERATEDCONSTR) == 0 &&
1002 TreeInfo.isSuperCall(body.stats.head)) {
1003 // enum constructors are not allowed to call super
1004 // directly, so make sure there aren't any super calls
1005 // in enum constructors, except in the compiler
1006 // generated one.
1007 log.error(tree.body.stats.head.pos(),
1008 "call.to.super.not.allowed.in.enum.ctor",
1009 env.enclClass.sym);
1010 }
1011 }
1013 // Attribute method body.
1014 attribStat(tree.body, localEnv);
1015 }
1016 localEnv.info.scope.leave();
1017 result = tree.type = m.type;
1018 chk.validateAnnotations(tree.mods.annotations, m);
1019 }
1020 finally {
1021 chk.setLint(prevLint);
1022 chk.setMethod(prevMethod);
1023 }
1024 }
1026 public void visitVarDef(JCVariableDecl tree) {
1027 // Local variables have not been entered yet, so we need to do it now:
1028 if (env.info.scope.owner.kind == MTH) {
1029 if (tree.sym != null) {
1030 // parameters have already been entered
1031 env.info.scope.enter(tree.sym);
1032 } else {
1033 memberEnter.memberEnter(tree, env);
1034 annotate.flush();
1035 }
1036 }
1038 VarSymbol v = tree.sym;
1039 Lint lint = env.info.lint.augment(v.annotations, v.flags());
1040 Lint prevLint = chk.setLint(lint);
1042 // Check that the variable's declared type is well-formed.
1043 chk.validate(tree.vartype, env);
1044 deferredLintHandler.flush(tree.pos());
1046 try {
1047 chk.checkDeprecatedAnnotation(tree.pos(), v);
1049 if (tree.init != null) {
1050 if ((v.flags_field & FINAL) != 0 &&
1051 !tree.init.hasTag(NEWCLASS) &&
1052 !tree.init.hasTag(LAMBDA) &&
1053 !tree.init.hasTag(REFERENCE)) {
1054 // In this case, `v' is final. Ensure that it's initializer is
1055 // evaluated.
1056 v.getConstValue(); // ensure initializer is evaluated
1057 } else {
1058 // Attribute initializer in a new environment
1059 // with the declared variable as owner.
1060 // Check that initializer conforms to variable's declared type.
1061 Env<AttrContext> initEnv = memberEnter.initEnv(tree, env);
1062 initEnv.info.lint = lint;
1063 // In order to catch self-references, we set the variable's
1064 // declaration position to maximal possible value, effectively
1065 // marking the variable as undefined.
1066 initEnv.info.enclVar = v;
1067 attribExpr(tree.init, initEnv, v.type);
1068 }
1069 }
1070 result = tree.type = v.type;
1071 chk.validateAnnotations(tree.mods.annotations, v);
1072 }
1073 finally {
1074 chk.setLint(prevLint);
1075 }
1076 }
1078 public void visitSkip(JCSkip tree) {
1079 result = null;
1080 }
1082 public void visitBlock(JCBlock tree) {
1083 if (env.info.scope.owner.kind == TYP) {
1084 // Block is a static or instance initializer;
1085 // let the owner of the environment be a freshly
1086 // created BLOCK-method.
1087 Env<AttrContext> localEnv =
1088 env.dup(tree, env.info.dup(env.info.scope.dupUnshared()));
1089 localEnv.info.scope.owner =
1090 new MethodSymbol(tree.flags | BLOCK, names.empty, null,
1091 env.info.scope.owner);
1092 if ((tree.flags & STATIC) != 0) localEnv.info.staticLevel++;
1093 attribStats(tree.stats, localEnv);
1094 } else {
1095 // Create a new local environment with a local scope.
1096 Env<AttrContext> localEnv =
1097 env.dup(tree, env.info.dup(env.info.scope.dup()));
1098 try {
1099 attribStats(tree.stats, localEnv);
1100 } finally {
1101 localEnv.info.scope.leave();
1102 }
1103 }
1104 result = null;
1105 }
1107 public void visitDoLoop(JCDoWhileLoop tree) {
1108 attribStat(tree.body, env.dup(tree));
1109 attribExpr(tree.cond, env, syms.booleanType);
1110 result = null;
1111 }
1113 public void visitWhileLoop(JCWhileLoop tree) {
1114 attribExpr(tree.cond, env, syms.booleanType);
1115 attribStat(tree.body, env.dup(tree));
1116 result = null;
1117 }
1119 public void visitForLoop(JCForLoop tree) {
1120 Env<AttrContext> loopEnv =
1121 env.dup(env.tree, env.info.dup(env.info.scope.dup()));
1122 try {
1123 attribStats(tree.init, loopEnv);
1124 if (tree.cond != null) attribExpr(tree.cond, loopEnv, syms.booleanType);
1125 loopEnv.tree = tree; // before, we were not in loop!
1126 attribStats(tree.step, loopEnv);
1127 attribStat(tree.body, loopEnv);
1128 result = null;
1129 }
1130 finally {
1131 loopEnv.info.scope.leave();
1132 }
1133 }
1135 public void visitForeachLoop(JCEnhancedForLoop tree) {
1136 Env<AttrContext> loopEnv =
1137 env.dup(env.tree, env.info.dup(env.info.scope.dup()));
1138 try {
1139 attribStat(tree.var, loopEnv);
1140 Type exprType = types.upperBound(attribExpr(tree.expr, loopEnv));
1141 chk.checkNonVoid(tree.pos(), exprType);
1142 Type elemtype = types.elemtype(exprType); // perhaps expr is an array?
1143 if (elemtype == null) {
1144 // or perhaps expr implements Iterable<T>?
1145 Type base = types.asSuper(exprType, syms.iterableType.tsym);
1146 if (base == null) {
1147 log.error(tree.expr.pos(),
1148 "foreach.not.applicable.to.type",
1149 exprType,
1150 diags.fragment("type.req.array.or.iterable"));
1151 elemtype = types.createErrorType(exprType);
1152 } else {
1153 List<Type> iterableParams = base.allparams();
1154 elemtype = iterableParams.isEmpty()
1155 ? syms.objectType
1156 : types.upperBound(iterableParams.head);
1157 }
1158 }
1159 chk.checkType(tree.expr.pos(), elemtype, tree.var.sym.type);
1160 loopEnv.tree = tree; // before, we were not in loop!
1161 attribStat(tree.body, loopEnv);
1162 result = null;
1163 }
1164 finally {
1165 loopEnv.info.scope.leave();
1166 }
1167 }
1169 public void visitLabelled(JCLabeledStatement tree) {
1170 // Check that label is not used in an enclosing statement
1171 Env<AttrContext> env1 = env;
1172 while (env1 != null && !env1.tree.hasTag(CLASSDEF)) {
1173 if (env1.tree.hasTag(LABELLED) &&
1174 ((JCLabeledStatement) env1.tree).label == tree.label) {
1175 log.error(tree.pos(), "label.already.in.use",
1176 tree.label);
1177 break;
1178 }
1179 env1 = env1.next;
1180 }
1182 attribStat(tree.body, env.dup(tree));
1183 result = null;
1184 }
1186 public void visitSwitch(JCSwitch tree) {
1187 Type seltype = attribExpr(tree.selector, env);
1189 Env<AttrContext> switchEnv =
1190 env.dup(tree, env.info.dup(env.info.scope.dup()));
1192 try {
1194 boolean enumSwitch =
1195 allowEnums &&
1196 (seltype.tsym.flags() & Flags.ENUM) != 0;
1197 boolean stringSwitch = false;
1198 if (types.isSameType(seltype, syms.stringType)) {
1199 if (allowStringsInSwitch) {
1200 stringSwitch = true;
1201 } else {
1202 log.error(tree.selector.pos(), "string.switch.not.supported.in.source", sourceName);
1203 }
1204 }
1205 if (!enumSwitch && !stringSwitch)
1206 seltype = chk.checkType(tree.selector.pos(), seltype, syms.intType);
1208 // Attribute all cases and
1209 // check that there are no duplicate case labels or default clauses.
1210 Set<Object> labels = new HashSet<Object>(); // The set of case labels.
1211 boolean hasDefault = false; // Is there a default label?
1212 for (List<JCCase> l = tree.cases; l.nonEmpty(); l = l.tail) {
1213 JCCase c = l.head;
1214 Env<AttrContext> caseEnv =
1215 switchEnv.dup(c, env.info.dup(switchEnv.info.scope.dup()));
1216 try {
1217 if (c.pat != null) {
1218 if (enumSwitch) {
1219 Symbol sym = enumConstant(c.pat, seltype);
1220 if (sym == null) {
1221 log.error(c.pat.pos(), "enum.label.must.be.unqualified.enum");
1222 } else if (!labels.add(sym)) {
1223 log.error(c.pos(), "duplicate.case.label");
1224 }
1225 } else {
1226 Type pattype = attribExpr(c.pat, switchEnv, seltype);
1227 if (!pattype.hasTag(ERROR)) {
1228 if (pattype.constValue() == null) {
1229 log.error(c.pat.pos(),
1230 (stringSwitch ? "string.const.req" : "const.expr.req"));
1231 } else if (labels.contains(pattype.constValue())) {
1232 log.error(c.pos(), "duplicate.case.label");
1233 } else {
1234 labels.add(pattype.constValue());
1235 }
1236 }
1237 }
1238 } else if (hasDefault) {
1239 log.error(c.pos(), "duplicate.default.label");
1240 } else {
1241 hasDefault = true;
1242 }
1243 attribStats(c.stats, caseEnv);
1244 } finally {
1245 caseEnv.info.scope.leave();
1246 addVars(c.stats, switchEnv.info.scope);
1247 }
1248 }
1250 result = null;
1251 }
1252 finally {
1253 switchEnv.info.scope.leave();
1254 }
1255 }
1256 // where
1257 /** Add any variables defined in stats to the switch scope. */
1258 private static void addVars(List<JCStatement> stats, Scope switchScope) {
1259 for (;stats.nonEmpty(); stats = stats.tail) {
1260 JCTree stat = stats.head;
1261 if (stat.hasTag(VARDEF))
1262 switchScope.enter(((JCVariableDecl) stat).sym);
1263 }
1264 }
1265 // where
1266 /** Return the selected enumeration constant symbol, or null. */
1267 private Symbol enumConstant(JCTree tree, Type enumType) {
1268 if (!tree.hasTag(IDENT)) {
1269 log.error(tree.pos(), "enum.label.must.be.unqualified.enum");
1270 return syms.errSymbol;
1271 }
1272 JCIdent ident = (JCIdent)tree;
1273 Name name = ident.name;
1274 for (Scope.Entry e = enumType.tsym.members().lookup(name);
1275 e.scope != null; e = e.next()) {
1276 if (e.sym.kind == VAR) {
1277 Symbol s = ident.sym = e.sym;
1278 ((VarSymbol)s).getConstValue(); // ensure initializer is evaluated
1279 ident.type = s.type;
1280 return ((s.flags_field & Flags.ENUM) == 0)
1281 ? null : s;
1282 }
1283 }
1284 return null;
1285 }
1287 public void visitSynchronized(JCSynchronized tree) {
1288 chk.checkRefType(tree.pos(), attribExpr(tree.lock, env));
1289 attribStat(tree.body, env);
1290 result = null;
1291 }
1293 public void visitTry(JCTry tree) {
1294 // Create a new local environment with a local
1295 Env<AttrContext> localEnv = env.dup(tree, env.info.dup(env.info.scope.dup()));
1296 try {
1297 boolean isTryWithResource = tree.resources.nonEmpty();
1298 // Create a nested environment for attributing the try block if needed
1299 Env<AttrContext> tryEnv = isTryWithResource ?
1300 env.dup(tree, localEnv.info.dup(localEnv.info.scope.dup())) :
1301 localEnv;
1302 try {
1303 // Attribute resource declarations
1304 for (JCTree resource : tree.resources) {
1305 CheckContext twrContext = new Check.NestedCheckContext(resultInfo.checkContext) {
1306 @Override
1307 public void report(DiagnosticPosition pos, JCDiagnostic details) {
1308 chk.basicHandler.report(pos, diags.fragment("try.not.applicable.to.type", details));
1309 }
1310 };
1311 ResultInfo twrResult = new ResultInfo(VAL, syms.autoCloseableType, twrContext);
1312 if (resource.hasTag(VARDEF)) {
1313 attribStat(resource, tryEnv);
1314 twrResult.check(resource, resource.type);
1316 //check that resource type cannot throw InterruptedException
1317 checkAutoCloseable(resource.pos(), localEnv, resource.type);
1319 VarSymbol var = (VarSymbol)TreeInfo.symbolFor(resource);
1320 var.setData(ElementKind.RESOURCE_VARIABLE);
1321 } else {
1322 attribTree(resource, tryEnv, twrResult);
1323 }
1324 }
1325 // Attribute body
1326 attribStat(tree.body, tryEnv);
1327 } finally {
1328 if (isTryWithResource)
1329 tryEnv.info.scope.leave();
1330 }
1332 // Attribute catch clauses
1333 for (List<JCCatch> l = tree.catchers; l.nonEmpty(); l = l.tail) {
1334 JCCatch c = l.head;
1335 Env<AttrContext> catchEnv =
1336 localEnv.dup(c, localEnv.info.dup(localEnv.info.scope.dup()));
1337 try {
1338 Type ctype = attribStat(c.param, catchEnv);
1339 if (TreeInfo.isMultiCatch(c)) {
1340 //multi-catch parameter is implicitly marked as final
1341 c.param.sym.flags_field |= FINAL | UNION;
1342 }
1343 if (c.param.sym.kind == Kinds.VAR) {
1344 c.param.sym.setData(ElementKind.EXCEPTION_PARAMETER);
1345 }
1346 chk.checkType(c.param.vartype.pos(),
1347 chk.checkClassType(c.param.vartype.pos(), ctype),
1348 syms.throwableType);
1349 attribStat(c.body, catchEnv);
1350 } finally {
1351 catchEnv.info.scope.leave();
1352 }
1353 }
1355 // Attribute finalizer
1356 if (tree.finalizer != null) attribStat(tree.finalizer, localEnv);
1357 result = null;
1358 }
1359 finally {
1360 localEnv.info.scope.leave();
1361 }
1362 }
1364 void checkAutoCloseable(DiagnosticPosition pos, Env<AttrContext> env, Type resource) {
1365 if (!resource.isErroneous() &&
1366 types.asSuper(resource, syms.autoCloseableType.tsym) != null &&
1367 !types.isSameType(resource, syms.autoCloseableType)) { // Don't emit warning for AutoCloseable itself
1368 Symbol close = syms.noSymbol;
1369 Log.DiagnosticHandler discardHandler = new Log.DiscardDiagnosticHandler(log);
1370 try {
1371 close = rs.resolveQualifiedMethod(pos,
1372 env,
1373 resource,
1374 names.close,
1375 List.<Type>nil(),
1376 List.<Type>nil());
1377 }
1378 finally {
1379 log.popDiagnosticHandler(discardHandler);
1380 }
1381 if (close.kind == MTH &&
1382 close.overrides(syms.autoCloseableClose, resource.tsym, types, true) &&
1383 chk.isHandled(syms.interruptedExceptionType, types.memberType(resource, close).getThrownTypes()) &&
1384 env.info.lint.isEnabled(LintCategory.TRY)) {
1385 log.warning(LintCategory.TRY, pos, "try.resource.throws.interrupted.exc", resource);
1386 }
1387 }
1388 }
1390 public void visitConditional(JCConditional tree) {
1391 Type condtype = attribExpr(tree.cond, env, syms.booleanType);
1393 boolean standaloneConditional = !allowPoly ||
1394 pt().hasTag(NONE) && pt() != Type.recoveryType ||
1395 isBooleanOrNumeric(env, tree);
1397 if (!standaloneConditional && resultInfo.pt.hasTag(VOID)) {
1398 //cannot get here (i.e. it means we are returning from void method - which is already an error)
1399 resultInfo.checkContext.report(tree, diags.fragment("conditional.target.cant.be.void"));
1400 result = tree.type = types.createErrorType(resultInfo.pt);
1401 return;
1402 }
1404 ResultInfo condInfo = standaloneConditional ?
1405 unknownExprInfo :
1406 resultInfo.dup(new Check.NestedCheckContext(resultInfo.checkContext) {
1407 //this will use enclosing check context to check compatibility of
1408 //subexpression against target type; if we are in a method check context,
1409 //depending on whether boxing is allowed, we could have incompatibilities
1410 @Override
1411 public void report(DiagnosticPosition pos, JCDiagnostic details) {
1412 enclosingContext.report(pos, diags.fragment("incompatible.type.in.conditional", details));
1413 }
1414 });
1416 Type truetype = attribTree(tree.truepart, env, condInfo);
1417 Type falsetype = attribTree(tree.falsepart, env, condInfo);
1419 Type owntype = standaloneConditional ? condType(tree, truetype, falsetype) : pt();
1420 if (condtype.constValue() != null &&
1421 truetype.constValue() != null &&
1422 falsetype.constValue() != null) {
1423 //constant folding
1424 owntype = cfolder.coerce(condtype.isTrue() ? truetype : falsetype, owntype);
1425 }
1426 result = check(tree, owntype, VAL, resultInfo);
1427 }
1428 //where
1429 private boolean isBooleanOrNumeric(Env<AttrContext> env, JCExpression tree) {
1430 switch (tree.getTag()) {
1431 case LITERAL: return ((JCLiteral)tree).typetag.isSubRangeOf(DOUBLE) ||
1432 ((JCLiteral)tree).typetag == BOOLEAN ||
1433 ((JCLiteral)tree).typetag == BOT;
1434 case LAMBDA: case REFERENCE: return false;
1435 case PARENS: return isBooleanOrNumeric(env, ((JCParens)tree).expr);
1436 case CONDEXPR:
1437 JCConditional condTree = (JCConditional)tree;
1438 return isBooleanOrNumeric(env, condTree.truepart) &&
1439 isBooleanOrNumeric(env, condTree.falsepart);
1440 default:
1441 Type speculativeType = deferredAttr.attribSpeculative(tree, env, unknownExprInfo).type;
1442 speculativeType = types.unboxedTypeOrType(speculativeType);
1443 return speculativeType.isPrimitive();
1444 }
1445 }
1447 /** Compute the type of a conditional expression, after
1448 * checking that it exists. See JLS 15.25. Does not take into
1449 * account the special case where condition and both arms
1450 * are constants.
1451 *
1452 * @param pos The source position to be used for error
1453 * diagnostics.
1454 * @param thentype The type of the expression's then-part.
1455 * @param elsetype The type of the expression's else-part.
1456 */
1457 private Type condType(DiagnosticPosition pos,
1458 Type thentype, Type elsetype) {
1459 // If same type, that is the result
1460 if (types.isSameType(thentype, elsetype))
1461 return thentype.baseType();
1463 Type thenUnboxed = (!allowBoxing || thentype.isPrimitive())
1464 ? thentype : types.unboxedType(thentype);
1465 Type elseUnboxed = (!allowBoxing || elsetype.isPrimitive())
1466 ? elsetype : types.unboxedType(elsetype);
1468 // Otherwise, if both arms can be converted to a numeric
1469 // type, return the least numeric type that fits both arms
1470 // (i.e. return larger of the two, or return int if one
1471 // arm is short, the other is char).
1472 if (thenUnboxed.isPrimitive() && elseUnboxed.isPrimitive()) {
1473 // If one arm has an integer subrange type (i.e., byte,
1474 // short, or char), and the other is an integer constant
1475 // that fits into the subrange, return the subrange type.
1476 if (thenUnboxed.getTag().isStrictSubRangeOf(INT) && elseUnboxed.hasTag(INT) &&
1477 types.isAssignable(elseUnboxed, thenUnboxed))
1478 return thenUnboxed.baseType();
1479 if (elseUnboxed.getTag().isStrictSubRangeOf(INT) && thenUnboxed.hasTag(INT) &&
1480 types.isAssignable(thenUnboxed, elseUnboxed))
1481 return elseUnboxed.baseType();
1483 for (TypeTag tag : TypeTag.values()) {
1484 if (tag.ordinal() >= TypeTag.getTypeTagCount()) break;
1485 Type candidate = syms.typeOfTag[tag.ordinal()];
1486 if (candidate != null &&
1487 candidate.isPrimitive() &&
1488 types.isSubtype(thenUnboxed, candidate) &&
1489 types.isSubtype(elseUnboxed, candidate))
1490 return candidate;
1491 }
1492 }
1494 // Those were all the cases that could result in a primitive
1495 if (allowBoxing) {
1496 if (thentype.isPrimitive())
1497 thentype = types.boxedClass(thentype).type;
1498 if (elsetype.isPrimitive())
1499 elsetype = types.boxedClass(elsetype).type;
1500 }
1502 if (types.isSubtype(thentype, elsetype))
1503 return elsetype.baseType();
1504 if (types.isSubtype(elsetype, thentype))
1505 return thentype.baseType();
1507 if (!allowBoxing || thentype.hasTag(VOID) || elsetype.hasTag(VOID)) {
1508 log.error(pos, "neither.conditional.subtype",
1509 thentype, elsetype);
1510 return thentype.baseType();
1511 }
1513 // both are known to be reference types. The result is
1514 // lub(thentype,elsetype). This cannot fail, as it will
1515 // always be possible to infer "Object" if nothing better.
1516 return types.lub(thentype.baseType(), elsetype.baseType());
1517 }
1519 public void visitIf(JCIf tree) {
1520 attribExpr(tree.cond, env, syms.booleanType);
1521 attribStat(tree.thenpart, env);
1522 if (tree.elsepart != null)
1523 attribStat(tree.elsepart, env);
1524 chk.checkEmptyIf(tree);
1525 result = null;
1526 }
1528 public void visitExec(JCExpressionStatement tree) {
1529 //a fresh environment is required for 292 inference to work properly ---
1530 //see Infer.instantiatePolymorphicSignatureInstance()
1531 Env<AttrContext> localEnv = env.dup(tree);
1532 attribExpr(tree.expr, localEnv);
1533 result = null;
1534 }
1536 public void visitBreak(JCBreak tree) {
1537 tree.target = findJumpTarget(tree.pos(), tree.getTag(), tree.label, env);
1538 result = null;
1539 }
1541 public void visitContinue(JCContinue tree) {
1542 tree.target = findJumpTarget(tree.pos(), tree.getTag(), tree.label, env);
1543 result = null;
1544 }
1545 //where
1546 /** Return the target of a break or continue statement, if it exists,
1547 * report an error if not.
1548 * Note: The target of a labelled break or continue is the
1549 * (non-labelled) statement tree referred to by the label,
1550 * not the tree representing the labelled statement itself.
1551 *
1552 * @param pos The position to be used for error diagnostics
1553 * @param tag The tag of the jump statement. This is either
1554 * Tree.BREAK or Tree.CONTINUE.
1555 * @param label The label of the jump statement, or null if no
1556 * label is given.
1557 * @param env The environment current at the jump statement.
1558 */
1559 private JCTree findJumpTarget(DiagnosticPosition pos,
1560 JCTree.Tag tag,
1561 Name label,
1562 Env<AttrContext> env) {
1563 // Search environments outwards from the point of jump.
1564 Env<AttrContext> env1 = env;
1565 LOOP:
1566 while (env1 != null) {
1567 switch (env1.tree.getTag()) {
1568 case LABELLED:
1569 JCLabeledStatement labelled = (JCLabeledStatement)env1.tree;
1570 if (label == labelled.label) {
1571 // If jump is a continue, check that target is a loop.
1572 if (tag == CONTINUE) {
1573 if (!labelled.body.hasTag(DOLOOP) &&
1574 !labelled.body.hasTag(WHILELOOP) &&
1575 !labelled.body.hasTag(FORLOOP) &&
1576 !labelled.body.hasTag(FOREACHLOOP))
1577 log.error(pos, "not.loop.label", label);
1578 // Found labelled statement target, now go inwards
1579 // to next non-labelled tree.
1580 return TreeInfo.referencedStatement(labelled);
1581 } else {
1582 return labelled;
1583 }
1584 }
1585 break;
1586 case DOLOOP:
1587 case WHILELOOP:
1588 case FORLOOP:
1589 case FOREACHLOOP:
1590 if (label == null) return env1.tree;
1591 break;
1592 case SWITCH:
1593 if (label == null && tag == BREAK) return env1.tree;
1594 break;
1595 case LAMBDA:
1596 case METHODDEF:
1597 case CLASSDEF:
1598 break LOOP;
1599 default:
1600 }
1601 env1 = env1.next;
1602 }
1603 if (label != null)
1604 log.error(pos, "undef.label", label);
1605 else if (tag == CONTINUE)
1606 log.error(pos, "cont.outside.loop");
1607 else
1608 log.error(pos, "break.outside.switch.loop");
1609 return null;
1610 }
1612 public void visitReturn(JCReturn tree) {
1613 // Check that there is an enclosing method which is
1614 // nested within than the enclosing class.
1615 if (env.info.returnResult == null) {
1616 log.error(tree.pos(), "ret.outside.meth");
1617 } else {
1618 // Attribute return expression, if it exists, and check that
1619 // it conforms to result type of enclosing method.
1620 if (tree.expr != null) {
1621 if (env.info.returnResult.pt.hasTag(VOID)) {
1622 env.info.returnResult.checkContext.report(tree.expr.pos(),
1623 diags.fragment("unexpected.ret.val"));
1624 }
1625 attribTree(tree.expr, env, env.info.returnResult);
1626 } else if (!env.info.returnResult.pt.hasTag(VOID)) {
1627 env.info.returnResult.checkContext.report(tree.pos(),
1628 diags.fragment("missing.ret.val"));
1629 }
1630 }
1631 result = null;
1632 }
1634 public void visitThrow(JCThrow tree) {
1635 Type owntype = attribExpr(tree.expr, env, allowPoly ? Type.noType : syms.throwableType);
1636 if (allowPoly) {
1637 chk.checkType(tree, owntype, syms.throwableType);
1638 }
1639 result = null;
1640 }
1642 public void visitAssert(JCAssert tree) {
1643 attribExpr(tree.cond, env, syms.booleanType);
1644 if (tree.detail != null) {
1645 chk.checkNonVoid(tree.detail.pos(), attribExpr(tree.detail, env));
1646 }
1647 result = null;
1648 }
1650 /** Visitor method for method invocations.
1651 * NOTE: The method part of an application will have in its type field
1652 * the return type of the method, not the method's type itself!
1653 */
1654 public void visitApply(JCMethodInvocation tree) {
1655 // The local environment of a method application is
1656 // a new environment nested in the current one.
1657 Env<AttrContext> localEnv = env.dup(tree, env.info.dup());
1659 // The types of the actual method arguments.
1660 List<Type> argtypes;
1662 // The types of the actual method type arguments.
1663 List<Type> typeargtypes = null;
1665 Name methName = TreeInfo.name(tree.meth);
1667 boolean isConstructorCall =
1668 methName == names._this || methName == names._super;
1670 if (isConstructorCall) {
1671 // We are seeing a ...this(...) or ...super(...) call.
1672 // Check that this is the first statement in a constructor.
1673 if (checkFirstConstructorStat(tree, env)) {
1675 // Record the fact
1676 // that this is a constructor call (using isSelfCall).
1677 localEnv.info.isSelfCall = true;
1679 // Attribute arguments, yielding list of argument types.
1680 argtypes = attribArgs(tree.args, localEnv);
1681 typeargtypes = attribTypes(tree.typeargs, localEnv);
1683 // Variable `site' points to the class in which the called
1684 // constructor is defined.
1685 Type site = env.enclClass.sym.type;
1686 if (methName == names._super) {
1687 if (site == syms.objectType) {
1688 log.error(tree.meth.pos(), "no.superclass", site);
1689 site = types.createErrorType(syms.objectType);
1690 } else {
1691 site = types.supertype(site);
1692 }
1693 }
1695 if (site.hasTag(CLASS)) {
1696 Type encl = site.getEnclosingType();
1697 while (encl != null && encl.hasTag(TYPEVAR))
1698 encl = encl.getUpperBound();
1699 if (encl.hasTag(CLASS)) {
1700 // we are calling a nested class
1702 if (tree.meth.hasTag(SELECT)) {
1703 JCTree qualifier = ((JCFieldAccess) tree.meth).selected;
1705 // We are seeing a prefixed call, of the form
1706 // <expr>.super(...).
1707 // Check that the prefix expression conforms
1708 // to the outer instance type of the class.
1709 chk.checkRefType(qualifier.pos(),
1710 attribExpr(qualifier, localEnv,
1711 encl));
1712 } else if (methName == names._super) {
1713 // qualifier omitted; check for existence
1714 // of an appropriate implicit qualifier.
1715 rs.resolveImplicitThis(tree.meth.pos(),
1716 localEnv, site, true);
1717 }
1718 } else if (tree.meth.hasTag(SELECT)) {
1719 log.error(tree.meth.pos(), "illegal.qual.not.icls",
1720 site.tsym);
1721 }
1723 // if we're calling a java.lang.Enum constructor,
1724 // prefix the implicit String and int parameters
1725 if (site.tsym == syms.enumSym && allowEnums)
1726 argtypes = argtypes.prepend(syms.intType).prepend(syms.stringType);
1728 // Resolve the called constructor under the assumption
1729 // that we are referring to a superclass instance of the
1730 // current instance (JLS ???).
1731 boolean selectSuperPrev = localEnv.info.selectSuper;
1732 localEnv.info.selectSuper = true;
1733 localEnv.info.pendingResolutionPhase = null;
1734 Symbol sym = rs.resolveConstructor(
1735 tree.meth.pos(), localEnv, site, argtypes, typeargtypes);
1736 localEnv.info.selectSuper = selectSuperPrev;
1738 // Set method symbol to resolved constructor...
1739 TreeInfo.setSymbol(tree.meth, sym);
1741 // ...and check that it is legal in the current context.
1742 // (this will also set the tree's type)
1743 Type mpt = newMethodTemplate(resultInfo.pt, argtypes, typeargtypes);
1744 checkId(tree.meth, site, sym, localEnv, new ResultInfo(MTH, mpt));
1745 }
1746 // Otherwise, `site' is an error type and we do nothing
1747 }
1748 result = tree.type = syms.voidType;
1749 } else {
1750 // Otherwise, we are seeing a regular method call.
1751 // Attribute the arguments, yielding list of argument types, ...
1752 argtypes = attribArgs(tree.args, localEnv);
1753 typeargtypes = attribAnyTypes(tree.typeargs, localEnv);
1755 // ... and attribute the method using as a prototype a methodtype
1756 // whose formal argument types is exactly the list of actual
1757 // arguments (this will also set the method symbol).
1758 Type mpt = newMethodTemplate(resultInfo.pt, argtypes, typeargtypes);
1759 localEnv.info.pendingResolutionPhase = null;
1760 Type mtype = attribTree(tree.meth, localEnv, new ResultInfo(VAL, mpt, resultInfo.checkContext));
1762 // Compute the result type.
1763 Type restype = mtype.getReturnType();
1764 if (restype.hasTag(WILDCARD))
1765 throw new AssertionError(mtype);
1767 Type qualifier = (tree.meth.hasTag(SELECT))
1768 ? ((JCFieldAccess) tree.meth).selected.type
1769 : env.enclClass.sym.type;
1770 restype = adjustMethodReturnType(qualifier, methName, argtypes, restype);
1772 chk.checkRefTypes(tree.typeargs, typeargtypes);
1774 // Check that value of resulting type is admissible in the
1775 // current context. Also, capture the return type
1776 result = check(tree, capture(restype), VAL, resultInfo);
1778 if (localEnv.info.lastResolveVarargs())
1779 Assert.check(result.isErroneous() || tree.varargsElement != null);
1780 }
1781 chk.validate(tree.typeargs, localEnv);
1782 }
1783 //where
1784 Type adjustMethodReturnType(Type qualifierType, Name methodName, List<Type> argtypes, Type restype) {
1785 if (allowCovariantReturns &&
1786 methodName == names.clone &&
1787 types.isArray(qualifierType)) {
1788 // as a special case, array.clone() has a result that is
1789 // the same as static type of the array being cloned
1790 return qualifierType;
1791 } else if (allowGenerics &&
1792 methodName == names.getClass &&
1793 argtypes.isEmpty()) {
1794 // as a special case, x.getClass() has type Class<? extends |X|>
1795 return new ClassType(restype.getEnclosingType(),
1796 List.<Type>of(new WildcardType(types.erasure(qualifierType),
1797 BoundKind.EXTENDS,
1798 syms.boundClass)),
1799 restype.tsym);
1800 } else {
1801 return restype;
1802 }
1803 }
1805 /** Check that given application node appears as first statement
1806 * in a constructor call.
1807 * @param tree The application node
1808 * @param env The environment current at the application.
1809 */
1810 boolean checkFirstConstructorStat(JCMethodInvocation tree, Env<AttrContext> env) {
1811 JCMethodDecl enclMethod = env.enclMethod;
1812 if (enclMethod != null && enclMethod.name == names.init) {
1813 JCBlock body = enclMethod.body;
1814 if (body.stats.head.hasTag(EXEC) &&
1815 ((JCExpressionStatement) body.stats.head).expr == tree)
1816 return true;
1817 }
1818 log.error(tree.pos(),"call.must.be.first.stmt.in.ctor",
1819 TreeInfo.name(tree.meth));
1820 return false;
1821 }
1823 /** Obtain a method type with given argument types.
1824 */
1825 Type newMethodTemplate(Type restype, List<Type> argtypes, List<Type> typeargtypes) {
1826 MethodType mt = new MethodType(argtypes, restype, List.<Type>nil(), syms.methodClass);
1827 return (typeargtypes == null) ? mt : (Type)new ForAll(typeargtypes, mt);
1828 }
1830 public void visitNewClass(final JCNewClass tree) {
1831 Type owntype = types.createErrorType(tree.type);
1833 // The local environment of a class creation is
1834 // a new environment nested in the current one.
1835 Env<AttrContext> localEnv = env.dup(tree, env.info.dup());
1837 // The anonymous inner class definition of the new expression,
1838 // if one is defined by it.
1839 JCClassDecl cdef = tree.def;
1841 // If enclosing class is given, attribute it, and
1842 // complete class name to be fully qualified
1843 JCExpression clazz = tree.clazz; // Class field following new
1844 JCExpression clazzid = // Identifier in class field
1845 (clazz.hasTag(TYPEAPPLY))
1846 ? ((JCTypeApply) clazz).clazz
1847 : clazz;
1849 JCExpression clazzid1 = clazzid; // The same in fully qualified form
1851 if (tree.encl != null) {
1852 // We are seeing a qualified new, of the form
1853 // <expr>.new C <...> (...) ...
1854 // In this case, we let clazz stand for the name of the
1855 // allocated class C prefixed with the type of the qualifier
1856 // expression, so that we can
1857 // resolve it with standard techniques later. I.e., if
1858 // <expr> has type T, then <expr>.new C <...> (...)
1859 // yields a clazz T.C.
1860 Type encltype = chk.checkRefType(tree.encl.pos(),
1861 attribExpr(tree.encl, env));
1862 clazzid1 = make.at(clazz.pos).Select(make.Type(encltype),
1863 ((JCIdent) clazzid).name);
1864 if (clazz.hasTag(TYPEAPPLY))
1865 clazz = make.at(tree.pos).
1866 TypeApply(clazzid1,
1867 ((JCTypeApply) clazz).arguments);
1868 else
1869 clazz = clazzid1;
1870 }
1872 // Attribute clazz expression and store
1873 // symbol + type back into the attributed tree.
1874 Type clazztype = TreeInfo.isEnumInit(env.tree) ?
1875 attribIdentAsEnumType(env, (JCIdent)clazz) :
1876 attribType(clazz, env);
1878 clazztype = chk.checkDiamond(tree, clazztype);
1879 chk.validate(clazz, localEnv);
1880 if (tree.encl != null) {
1881 // We have to work in this case to store
1882 // symbol + type back into the attributed tree.
1883 tree.clazz.type = clazztype;
1884 TreeInfo.setSymbol(clazzid, TreeInfo.symbol(clazzid1));
1885 clazzid.type = ((JCIdent) clazzid).sym.type;
1886 if (!clazztype.isErroneous()) {
1887 if (cdef != null && clazztype.tsym.isInterface()) {
1888 log.error(tree.encl.pos(), "anon.class.impl.intf.no.qual.for.new");
1889 } else if (clazztype.tsym.isStatic()) {
1890 log.error(tree.encl.pos(), "qualified.new.of.static.class", clazztype.tsym);
1891 }
1892 }
1893 } else if (!clazztype.tsym.isInterface() &&
1894 clazztype.getEnclosingType().hasTag(CLASS)) {
1895 // Check for the existence of an apropos outer instance
1896 rs.resolveImplicitThis(tree.pos(), env, clazztype);
1897 }
1899 // Attribute constructor arguments.
1900 List<Type> argtypes = attribArgs(tree.args, localEnv);
1901 List<Type> typeargtypes = attribTypes(tree.typeargs, localEnv);
1903 // If we have made no mistakes in the class type...
1904 if (clazztype.hasTag(CLASS)) {
1905 // Enums may not be instantiated except implicitly
1906 if (allowEnums &&
1907 (clazztype.tsym.flags_field&Flags.ENUM) != 0 &&
1908 (!env.tree.hasTag(VARDEF) ||
1909 (((JCVariableDecl) env.tree).mods.flags&Flags.ENUM) == 0 ||
1910 ((JCVariableDecl) env.tree).init != tree))
1911 log.error(tree.pos(), "enum.cant.be.instantiated");
1912 // Check that class is not abstract
1913 if (cdef == null &&
1914 (clazztype.tsym.flags() & (ABSTRACT | INTERFACE)) != 0) {
1915 log.error(tree.pos(), "abstract.cant.be.instantiated",
1916 clazztype.tsym);
1917 } else if (cdef != null && clazztype.tsym.isInterface()) {
1918 // Check that no constructor arguments are given to
1919 // anonymous classes implementing an interface
1920 if (!argtypes.isEmpty())
1921 log.error(tree.args.head.pos(), "anon.class.impl.intf.no.args");
1923 if (!typeargtypes.isEmpty())
1924 log.error(tree.typeargs.head.pos(), "anon.class.impl.intf.no.typeargs");
1926 // Error recovery: pretend no arguments were supplied.
1927 argtypes = List.nil();
1928 typeargtypes = List.nil();
1929 } else if (TreeInfo.isDiamond(tree)) {
1930 ClassType site = new ClassType(clazztype.getEnclosingType(),
1931 clazztype.tsym.type.getTypeArguments(),
1932 clazztype.tsym);
1934 Env<AttrContext> diamondEnv = localEnv.dup(tree);
1935 diamondEnv.info.selectSuper = cdef != null;
1936 diamondEnv.info.pendingResolutionPhase = null;
1938 //if the type of the instance creation expression is a class type
1939 //apply method resolution inference (JLS 15.12.2.7). The return type
1940 //of the resolved constructor will be a partially instantiated type
1941 Symbol constructor = rs.resolveDiamond(tree.pos(),
1942 diamondEnv,
1943 site,
1944 argtypes,
1945 typeargtypes);
1946 tree.constructor = constructor.baseSymbol();
1948 final TypeSymbol csym = clazztype.tsym;
1949 ResultInfo diamondResult = new ResultInfo(MTH, newMethodTemplate(resultInfo.pt, argtypes, typeargtypes), new Check.NestedCheckContext(resultInfo.checkContext) {
1950 @Override
1951 public void report(DiagnosticPosition _unused, JCDiagnostic details) {
1952 enclosingContext.report(tree.clazz,
1953 diags.fragment("cant.apply.diamond.1", diags.fragment("diamond", csym), details));
1954 }
1955 });
1956 Type constructorType = tree.constructorType = types.createErrorType(clazztype);
1957 constructorType = checkId(tree, site,
1958 constructor,
1959 diamondEnv,
1960 diamondResult);
1962 tree.clazz.type = types.createErrorType(clazztype);
1963 if (!constructorType.isErroneous()) {
1964 tree.clazz.type = clazztype = constructorType.getReturnType();
1965 tree.constructorType = types.createMethodTypeWithReturn(constructorType, syms.voidType);
1966 }
1967 clazztype = chk.checkClassType(tree.clazz, tree.clazz.type, true);
1968 }
1970 // Resolve the called constructor under the assumption
1971 // that we are referring to a superclass instance of the
1972 // current instance (JLS ???).
1973 else {
1974 //the following code alters some of the fields in the current
1975 //AttrContext - hence, the current context must be dup'ed in
1976 //order to avoid downstream failures
1977 Env<AttrContext> rsEnv = localEnv.dup(tree);
1978 rsEnv.info.selectSuper = cdef != null;
1979 rsEnv.info.pendingResolutionPhase = null;
1980 tree.constructor = rs.resolveConstructor(
1981 tree.pos(), rsEnv, clazztype, argtypes, typeargtypes);
1982 if (cdef == null) { //do not check twice!
1983 tree.constructorType = checkId(tree,
1984 clazztype,
1985 tree.constructor,
1986 rsEnv,
1987 new ResultInfo(MTH, newMethodTemplate(syms.voidType, argtypes, typeargtypes)));
1988 if (rsEnv.info.lastResolveVarargs())
1989 Assert.check(tree.constructorType.isErroneous() || tree.varargsElement != null);
1990 }
1991 findDiamondIfNeeded(localEnv, tree, clazztype);
1992 }
1994 if (cdef != null) {
1995 // We are seeing an anonymous class instance creation.
1996 // In this case, the class instance creation
1997 // expression
1998 //
1999 // E.new <typeargs1>C<typargs2>(args) { ... }
2000 //
2001 // is represented internally as
2002 //
2003 // E . new <typeargs1>C<typargs2>(args) ( class <empty-name> { ... } ) .
2004 //
2005 // This expression is then *transformed* as follows:
2006 //
2007 // (1) add a STATIC flag to the class definition
2008 // if the current environment is static
2009 // (2) add an extends or implements clause
2010 // (3) add a constructor.
2011 //
2012 // For instance, if C is a class, and ET is the type of E,
2013 // the expression
2014 //
2015 // E.new <typeargs1>C<typargs2>(args) { ... }
2016 //
2017 // is translated to (where X is a fresh name and typarams is the
2018 // parameter list of the super constructor):
2019 //
2020 // new <typeargs1>X(<*nullchk*>E, args) where
2021 // X extends C<typargs2> {
2022 // <typarams> X(ET e, args) {
2023 // e.<typeargs1>super(args)
2024 // }
2025 // ...
2026 // }
2027 if (Resolve.isStatic(env)) cdef.mods.flags |= STATIC;
2029 if (clazztype.tsym.isInterface()) {
2030 cdef.implementing = List.of(clazz);
2031 } else {
2032 cdef.extending = clazz;
2033 }
2035 attribStat(cdef, localEnv);
2037 checkLambdaCandidate(tree, cdef.sym, clazztype);
2039 // If an outer instance is given,
2040 // prefix it to the constructor arguments
2041 // and delete it from the new expression
2042 if (tree.encl != null && !clazztype.tsym.isInterface()) {
2043 tree.args = tree.args.prepend(makeNullCheck(tree.encl));
2044 argtypes = argtypes.prepend(tree.encl.type);
2045 tree.encl = null;
2046 }
2048 // Reassign clazztype and recompute constructor.
2049 clazztype = cdef.sym.type;
2050 Symbol sym = tree.constructor = rs.resolveConstructor(
2051 tree.pos(), localEnv, clazztype, argtypes, typeargtypes);
2052 Assert.check(sym.kind < AMBIGUOUS);
2053 tree.constructor = sym;
2054 tree.constructorType = checkId(tree,
2055 clazztype,
2056 tree.constructor,
2057 localEnv,
2058 new ResultInfo(VAL, newMethodTemplate(syms.voidType, argtypes, typeargtypes)));
2059 }
2061 if (tree.constructor != null && tree.constructor.kind == MTH)
2062 owntype = clazztype;
2063 }
2064 result = check(tree, owntype, VAL, resultInfo);
2065 chk.validate(tree.typeargs, localEnv);
2066 }
2067 //where
2068 void findDiamondIfNeeded(Env<AttrContext> env, JCNewClass tree, Type clazztype) {
2069 if (tree.def == null &&
2070 !clazztype.isErroneous() &&
2071 clazztype.getTypeArguments().nonEmpty() &&
2072 findDiamonds) {
2073 JCTypeApply ta = (JCTypeApply)tree.clazz;
2074 List<JCExpression> prevTypeargs = ta.arguments;
2075 try {
2076 //create a 'fake' diamond AST node by removing type-argument trees
2077 ta.arguments = List.nil();
2078 ResultInfo findDiamondResult = new ResultInfo(VAL,
2079 resultInfo.checkContext.inferenceContext().free(resultInfo.pt) ? Type.noType : pt());
2080 Type inferred = deferredAttr.attribSpeculative(tree, env, findDiamondResult).type;
2081 if (!inferred.isErroneous() &&
2082 types.isAssignable(inferred, pt().hasTag(NONE) ? syms.objectType : pt(), types.noWarnings)) {
2083 String key = types.isSameType(clazztype, inferred) ?
2084 "diamond.redundant.args" :
2085 "diamond.redundant.args.1";
2086 log.warning(tree.clazz.pos(), key, clazztype, inferred);
2087 }
2088 } finally {
2089 ta.arguments = prevTypeargs;
2090 }
2091 }
2092 }
2094 private void checkLambdaCandidate(JCNewClass tree, ClassSymbol csym, Type clazztype) {
2095 if (allowLambda &&
2096 identifyLambdaCandidate &&
2097 clazztype.hasTag(CLASS) &&
2098 !pt().hasTag(NONE) &&
2099 types.isFunctionalInterface(clazztype.tsym)) {
2100 Symbol descriptor = types.findDescriptorSymbol(clazztype.tsym);
2101 int count = 0;
2102 boolean found = false;
2103 for (Symbol sym : csym.members().getElements()) {
2104 if ((sym.flags() & SYNTHETIC) != 0 ||
2105 sym.isConstructor()) continue;
2106 count++;
2107 if (sym.kind != MTH ||
2108 !sym.name.equals(descriptor.name)) continue;
2109 Type mtype = types.memberType(clazztype, sym);
2110 if (types.overrideEquivalent(mtype, types.memberType(clazztype, descriptor))) {
2111 found = true;
2112 }
2113 }
2114 if (found && count == 1) {
2115 log.note(tree.def, "potential.lambda.found");
2116 }
2117 }
2118 }
2120 /** Make an attributed null check tree.
2121 */
2122 public JCExpression makeNullCheck(JCExpression arg) {
2123 // optimization: X.this is never null; skip null check
2124 Name name = TreeInfo.name(arg);
2125 if (name == names._this || name == names._super) return arg;
2127 JCTree.Tag optag = NULLCHK;
2128 JCUnary tree = make.at(arg.pos).Unary(optag, arg);
2129 tree.operator = syms.nullcheck;
2130 tree.type = arg.type;
2131 return tree;
2132 }
2134 public void visitNewArray(JCNewArray tree) {
2135 Type owntype = types.createErrorType(tree.type);
2136 Env<AttrContext> localEnv = env.dup(tree);
2137 Type elemtype;
2138 if (tree.elemtype != null) {
2139 elemtype = attribType(tree.elemtype, localEnv);
2140 chk.validate(tree.elemtype, localEnv);
2141 owntype = elemtype;
2142 for (List<JCExpression> l = tree.dims; l.nonEmpty(); l = l.tail) {
2143 attribExpr(l.head, localEnv, syms.intType);
2144 owntype = new ArrayType(owntype, syms.arrayClass);
2145 }
2146 } else {
2147 // we are seeing an untyped aggregate { ... }
2148 // this is allowed only if the prototype is an array
2149 if (pt().hasTag(ARRAY)) {
2150 elemtype = types.elemtype(pt());
2151 } else {
2152 if (!pt().hasTag(ERROR)) {
2153 log.error(tree.pos(), "illegal.initializer.for.type",
2154 pt());
2155 }
2156 elemtype = types.createErrorType(pt());
2157 }
2158 }
2159 if (tree.elems != null) {
2160 attribExprs(tree.elems, localEnv, elemtype);
2161 owntype = new ArrayType(elemtype, syms.arrayClass);
2162 }
2163 if (!types.isReifiable(elemtype))
2164 log.error(tree.pos(), "generic.array.creation");
2165 result = check(tree, owntype, VAL, resultInfo);
2166 }
2168 /*
2169 * A lambda expression can only be attributed when a target-type is available.
2170 * In addition, if the target-type is that of a functional interface whose
2171 * descriptor contains inference variables in argument position the lambda expression
2172 * is 'stuck' (see DeferredAttr).
2173 */
2174 @Override
2175 public void visitLambda(final JCLambda that) {
2176 if (pt().isErroneous() || (pt().hasTag(NONE) && pt() != Type.recoveryType)) {
2177 if (pt().hasTag(NONE)) {
2178 //lambda only allowed in assignment or method invocation/cast context
2179 log.error(that.pos(), "unexpected.lambda");
2180 }
2181 result = that.type = types.createErrorType(pt());
2182 return;
2183 }
2184 //create an environment for attribution of the lambda expression
2185 final Env<AttrContext> localEnv = lambdaEnv(that, env);
2186 boolean needsRecovery =
2187 resultInfo.checkContext.deferredAttrContext().mode == DeferredAttr.AttrMode.CHECK;
2188 try {
2189 List<Type> explicitParamTypes = null;
2190 if (TreeInfo.isExplicitLambda(that)) {
2191 //attribute lambda parameters
2192 attribStats(that.params, localEnv);
2193 explicitParamTypes = TreeInfo.types(that.params);
2194 }
2196 Type target;
2197 Type lambdaType;
2198 if (pt() != Type.recoveryType) {
2199 target = infer.instantiateFunctionalInterface(that, pt(), explicitParamTypes, resultInfo.checkContext);
2200 lambdaType = types.findDescriptorType(target);
2201 chk.checkFunctionalInterface(that, target);
2202 } else {
2203 target = Type.recoveryType;
2204 lambdaType = fallbackDescriptorType(that);
2205 }
2207 if (!TreeInfo.isExplicitLambda(that)) {
2208 //add param type info in the AST
2209 List<Type> actuals = lambdaType.getParameterTypes();
2210 List<JCVariableDecl> params = that.params;
2212 boolean arityMismatch = false;
2214 while (params.nonEmpty()) {
2215 if (actuals.isEmpty()) {
2216 //not enough actuals to perform lambda parameter inference
2217 arityMismatch = true;
2218 }
2219 //reset previously set info
2220 Type argType = arityMismatch ?
2221 syms.errType :
2222 actuals.head;
2223 params.head.vartype = make.Type(argType);
2224 params.head.sym = null;
2225 actuals = actuals.isEmpty() ?
2226 actuals :
2227 actuals.tail;
2228 params = params.tail;
2229 }
2231 //attribute lambda parameters
2232 attribStats(that.params, localEnv);
2234 if (arityMismatch) {
2235 resultInfo.checkContext.report(that, diags.fragment("incompatible.arg.types.in.lambda"));
2236 result = that.type = types.createErrorType(target);
2237 return;
2238 }
2239 }
2241 //from this point on, no recovery is needed; if we are in assignment context
2242 //we will be able to attribute the whole lambda body, regardless of errors;
2243 //if we are in a 'check' method context, and the lambda is not compatible
2244 //with the target-type, it will be recovered anyway in Attr.checkId
2245 needsRecovery = false;
2247 FunctionalReturnContext funcContext = that.getBodyKind() == JCLambda.BodyKind.EXPRESSION ?
2248 new ExpressionLambdaReturnContext((JCExpression)that.getBody(), resultInfo.checkContext) :
2249 new FunctionalReturnContext(resultInfo.checkContext);
2251 ResultInfo bodyResultInfo = lambdaType.getReturnType() == Type.recoveryType ?
2252 recoveryInfo :
2253 new ResultInfo(VAL, lambdaType.getReturnType(), funcContext);
2254 localEnv.info.returnResult = bodyResultInfo;
2256 if (that.getBodyKind() == JCLambda.BodyKind.EXPRESSION) {
2257 attribTree(that.getBody(), localEnv, bodyResultInfo);
2258 } else {
2259 JCBlock body = (JCBlock)that.body;
2260 attribStats(body.stats, localEnv);
2261 }
2263 result = check(that, target, VAL, resultInfo);
2265 boolean isSpeculativeRound =
2266 resultInfo.checkContext.deferredAttrContext().mode == DeferredAttr.AttrMode.SPECULATIVE;
2268 postAttr(that);
2269 flow.analyzeLambda(env, that, make, isSpeculativeRound);
2271 checkLambdaCompatible(that, lambdaType, resultInfo.checkContext, isSpeculativeRound);
2273 if (!isSpeculativeRound) {
2274 checkAccessibleTypes(that, localEnv, resultInfo.checkContext.inferenceContext(), lambdaType, target);
2275 }
2276 result = check(that, target, VAL, resultInfo);
2277 } catch (Types.FunctionDescriptorLookupError ex) {
2278 JCDiagnostic cause = ex.getDiagnostic();
2279 resultInfo.checkContext.report(that, cause);
2280 result = that.type = types.createErrorType(pt());
2281 return;
2282 } finally {
2283 localEnv.info.scope.leave();
2284 if (needsRecovery) {
2285 attribTree(that, env, recoveryInfo);
2286 }
2287 }
2288 }
2289 //where
2290 private Type fallbackDescriptorType(JCExpression tree) {
2291 switch (tree.getTag()) {
2292 case LAMBDA:
2293 JCLambda lambda = (JCLambda)tree;
2294 List<Type> argtypes = List.nil();
2295 for (JCVariableDecl param : lambda.params) {
2296 argtypes = param.vartype != null ?
2297 argtypes.append(param.vartype.type) :
2298 argtypes.append(syms.errType);
2299 }
2300 return new MethodType(argtypes, Type.recoveryType, List.<Type>nil(), syms.methodClass);
2301 case REFERENCE:
2302 return new MethodType(List.<Type>nil(), Type.recoveryType, List.<Type>nil(), syms.methodClass);
2303 default:
2304 Assert.error("Cannot get here!");
2305 }
2306 return null;
2307 }
2309 private void checkAccessibleTypes(final DiagnosticPosition pos, final Env<AttrContext> env, final InferenceContext inferenceContext, final Type... ts) {
2310 checkAccessibleTypes(pos, env, inferenceContext, List.from(ts));
2311 }
2313 private void checkAccessibleTypes(final DiagnosticPosition pos, final Env<AttrContext> env, final InferenceContext inferenceContext, final List<Type> ts) {
2314 if (inferenceContext.free(ts)) {
2315 inferenceContext.addFreeTypeListener(ts, new FreeTypeListener() {
2316 @Override
2317 public void typesInferred(InferenceContext inferenceContext) {
2318 checkAccessibleTypes(pos, env, inferenceContext, inferenceContext.asInstTypes(ts, types));
2319 }
2320 });
2321 } else {
2322 for (Type t : ts) {
2323 rs.checkAccessibleType(env, t);
2324 }
2325 }
2326 }
2328 /**
2329 * Lambda/method reference have a special check context that ensures
2330 * that i.e. a lambda return type is compatible with the expected
2331 * type according to both the inherited context and the assignment
2332 * context.
2333 */
2334 class FunctionalReturnContext extends Check.NestedCheckContext {
2336 FunctionalReturnContext(CheckContext enclosingContext) {
2337 super(enclosingContext);
2338 }
2340 @Override
2341 public boolean compatible(Type found, Type req, Warner warn) {
2342 //return type must be compatible in both current context and assignment context
2343 return types.isAssignable(found, inferenceContext().asFree(req, types), warn) &&
2344 super.compatible(found, req, warn);
2345 }
2346 @Override
2347 public void report(DiagnosticPosition pos, JCDiagnostic details) {
2348 enclosingContext.report(pos, diags.fragment("incompatible.ret.type.in.lambda", details));
2349 }
2350 }
2352 class ExpressionLambdaReturnContext extends FunctionalReturnContext {
2354 JCExpression expr;
2356 ExpressionLambdaReturnContext(JCExpression expr, CheckContext enclosingContext) {
2357 super(enclosingContext);
2358 this.expr = expr;
2359 }
2361 @Override
2362 public boolean compatible(Type found, Type req, Warner warn) {
2363 //a void return is compatible with an expression statement lambda
2364 return TreeInfo.isExpressionStatement(expr) && req.hasTag(VOID) ||
2365 super.compatible(found, req, warn);
2366 }
2367 }
2369 /**
2370 * Lambda compatibility. Check that given return types, thrown types, parameter types
2371 * are compatible with the expected functional interface descriptor. This means that:
2372 * (i) parameter types must be identical to those of the target descriptor; (ii) return
2373 * types must be compatible with the return type of the expected descriptor;
2374 * (iii) thrown types must be 'included' in the thrown types list of the expected
2375 * descriptor.
2376 */
2377 private void checkLambdaCompatible(JCLambda tree, Type descriptor, CheckContext checkContext, boolean speculativeAttr) {
2378 Type returnType = checkContext.inferenceContext().asFree(descriptor.getReturnType(), types);
2380 //return values have already been checked - but if lambda has no return
2381 //values, we must ensure that void/value compatibility is correct;
2382 //this amounts at checking that, if a lambda body can complete normally,
2383 //the descriptor's return type must be void
2384 if (tree.getBodyKind() == JCLambda.BodyKind.STATEMENT && tree.canCompleteNormally &&
2385 !returnType.hasTag(VOID) && returnType != Type.recoveryType) {
2386 checkContext.report(tree, diags.fragment("incompatible.ret.type.in.lambda",
2387 diags.fragment("missing.ret.val", returnType)));
2388 }
2390 List<Type> argTypes = checkContext.inferenceContext().asFree(descriptor.getParameterTypes(), types);
2391 if (!types.isSameTypes(argTypes, TreeInfo.types(tree.params))) {
2392 checkContext.report(tree, diags.fragment("incompatible.arg.types.in.lambda"));
2393 }
2395 if (!speculativeAttr) {
2396 List<Type> thrownTypes = checkContext.inferenceContext().asFree(descriptor.getThrownTypes(), types);
2397 if (chk.unhandled(tree.inferredThrownTypes == null ? List.<Type>nil() : tree.inferredThrownTypes, thrownTypes).nonEmpty()) {
2398 log.error(tree, "incompatible.thrown.types.in.lambda", tree.inferredThrownTypes);
2399 }
2400 }
2401 }
2403 private Env<AttrContext> lambdaEnv(JCLambda that, Env<AttrContext> env) {
2404 Env<AttrContext> lambdaEnv;
2405 Symbol owner = env.info.scope.owner;
2406 if (owner.kind == VAR && owner.owner.kind == TYP) {
2407 //field initializer
2408 lambdaEnv = env.dup(that, env.info.dup(env.info.scope.dupUnshared()));
2409 lambdaEnv.info.scope.owner =
2410 new MethodSymbol(0, names.empty, null,
2411 env.info.scope.owner);
2412 } else {
2413 lambdaEnv = env.dup(that, env.info.dup(env.info.scope.dup()));
2414 }
2415 return lambdaEnv;
2416 }
2418 @Override
2419 public void visitReference(final JCMemberReference that) {
2420 if (pt().isErroneous() || (pt().hasTag(NONE) && pt() != Type.recoveryType)) {
2421 if (pt().hasTag(NONE)) {
2422 //method reference only allowed in assignment or method invocation/cast context
2423 log.error(that.pos(), "unexpected.mref");
2424 }
2425 result = that.type = types.createErrorType(pt());
2426 return;
2427 }
2428 final Env<AttrContext> localEnv = env.dup(that);
2429 try {
2430 //attribute member reference qualifier - if this is a constructor
2431 //reference, the expected kind must be a type
2432 Type exprType = attribTree(that.expr,
2433 env, new ResultInfo(that.getMode() == ReferenceMode.INVOKE ? VAL | TYP : TYP, Type.noType));
2435 if (that.getMode() == JCMemberReference.ReferenceMode.NEW) {
2436 exprType = chk.checkConstructorRefType(that.expr, exprType);
2437 }
2439 if (exprType.isErroneous()) {
2440 //if the qualifier expression contains problems,
2441 //give up atttribution of method reference
2442 result = that.type = exprType;
2443 return;
2444 }
2446 if (TreeInfo.isStaticSelector(that.expr, names) &&
2447 (that.getMode() != ReferenceMode.NEW || !that.expr.type.isRaw())) {
2448 //if the qualifier is a type, validate it
2449 chk.validate(that.expr, env);
2450 }
2452 //attrib type-arguments
2453 List<Type> typeargtypes = null;
2454 if (that.typeargs != null) {
2455 typeargtypes = attribTypes(that.typeargs, localEnv);
2456 }
2458 Type target;
2459 Type desc;
2460 if (pt() != Type.recoveryType) {
2461 target = infer.instantiateFunctionalInterface(that, pt(), null, resultInfo.checkContext);
2462 desc = types.findDescriptorType(target);
2463 chk.checkFunctionalInterface(that, target);
2464 } else {
2465 target = Type.recoveryType;
2466 desc = fallbackDescriptorType(that);
2467 }
2469 List<Type> argtypes = desc.getParameterTypes();
2471 boolean allowBoxing =
2472 resultInfo.checkContext.deferredAttrContext().phase.isBoxingRequired();
2473 Pair<Symbol, Resolve.ReferenceLookupHelper> refResult = rs.resolveMemberReference(that.pos(), localEnv, that,
2474 that.expr.type, that.name, argtypes, typeargtypes, allowBoxing);
2476 Symbol refSym = refResult.fst;
2477 Resolve.ReferenceLookupHelper lookupHelper = refResult.snd;
2479 if (refSym.kind != MTH) {
2480 boolean targetError;
2481 switch (refSym.kind) {
2482 case ABSENT_MTH:
2483 targetError = false;
2484 break;
2485 case WRONG_MTH:
2486 case WRONG_MTHS:
2487 case AMBIGUOUS:
2488 case HIDDEN:
2489 case STATICERR:
2490 case MISSING_ENCL:
2491 targetError = true;
2492 break;
2493 default:
2494 Assert.error("unexpected result kind " + refSym.kind);
2495 targetError = false;
2496 }
2498 JCDiagnostic detailsDiag = ((Resolve.ResolveError)refSym).getDiagnostic(JCDiagnostic.DiagnosticType.FRAGMENT,
2499 that, exprType.tsym, exprType, that.name, argtypes, typeargtypes);
2501 JCDiagnostic.DiagnosticType diagKind = targetError ?
2502 JCDiagnostic.DiagnosticType.FRAGMENT : JCDiagnostic.DiagnosticType.ERROR;
2504 JCDiagnostic diag = diags.create(diagKind, log.currentSource(), that,
2505 "invalid.mref", Kinds.kindName(that.getMode()), detailsDiag);
2507 if (targetError && target == Type.recoveryType) {
2508 //a target error doesn't make sense during recovery stage
2509 //as we don't know what actual parameter types are
2510 result = that.type = target;
2511 return;
2512 } else {
2513 if (targetError) {
2514 resultInfo.checkContext.report(that, diag);
2515 } else {
2516 log.report(diag);
2517 }
2518 result = that.type = types.createErrorType(target);
2519 return;
2520 }
2521 }
2523 if (desc.getReturnType() == Type.recoveryType) {
2524 // stop here
2525 result = that.type = target;
2526 return;
2527 }
2529 that.sym = refSym.baseSymbol();
2530 that.kind = lookupHelper.referenceKind(that.sym);
2532 ResultInfo checkInfo =
2533 resultInfo.dup(newMethodTemplate(
2534 desc.getReturnType().hasTag(VOID) ? Type.noType : desc.getReturnType(),
2535 lookupHelper.argtypes,
2536 typeargtypes));
2538 Type refType = checkId(that, lookupHelper.site, refSym, localEnv, checkInfo);
2540 if (!refType.isErroneous()) {
2541 refType = types.createMethodTypeWithReturn(refType,
2542 adjustMethodReturnType(lookupHelper.site, that.name, checkInfo.pt.getParameterTypes(), refType.getReturnType()));
2543 }
2545 //go ahead with standard method reference compatibility check - note that param check
2546 //is a no-op (as this has been taken care during method applicability)
2547 boolean isSpeculativeRound =
2548 resultInfo.checkContext.deferredAttrContext().mode == DeferredAttr.AttrMode.SPECULATIVE;
2549 checkReferenceCompatible(that, desc, refType, resultInfo.checkContext, isSpeculativeRound);
2550 if (!isSpeculativeRound) {
2551 checkAccessibleTypes(that, localEnv, resultInfo.checkContext.inferenceContext(), desc, target);
2552 }
2553 result = check(that, target, VAL, resultInfo);
2554 } catch (Types.FunctionDescriptorLookupError ex) {
2555 JCDiagnostic cause = ex.getDiagnostic();
2556 resultInfo.checkContext.report(that, cause);
2557 result = that.type = types.createErrorType(pt());
2558 return;
2559 }
2560 }
2562 @SuppressWarnings("fallthrough")
2563 void checkReferenceCompatible(JCMemberReference tree, Type descriptor, Type refType, CheckContext checkContext, boolean speculativeAttr) {
2564 Type returnType = checkContext.inferenceContext().asFree(descriptor.getReturnType(), types);
2566 Type resType;
2567 switch (tree.getMode()) {
2568 case NEW:
2569 if (!tree.expr.type.isRaw()) {
2570 resType = tree.expr.type;
2571 break;
2572 }
2573 default:
2574 resType = refType.getReturnType();
2575 }
2577 Type incompatibleReturnType = resType;
2579 if (returnType.hasTag(VOID)) {
2580 incompatibleReturnType = null;
2581 }
2583 if (!returnType.hasTag(VOID) && !resType.hasTag(VOID)) {
2584 if (resType.isErroneous() ||
2585 new FunctionalReturnContext(checkContext).compatible(resType, returnType, types.noWarnings)) {
2586 incompatibleReturnType = null;
2587 }
2588 }
2590 if (incompatibleReturnType != null) {
2591 checkContext.report(tree, diags.fragment("incompatible.ret.type.in.mref",
2592 diags.fragment("inconvertible.types", resType, descriptor.getReturnType())));
2593 }
2595 if (!speculativeAttr) {
2596 List<Type> thrownTypes = checkContext.inferenceContext().asFree(descriptor.getThrownTypes(), types);
2597 if (chk.unhandled(refType.getThrownTypes(), thrownTypes).nonEmpty()) {
2598 log.error(tree, "incompatible.thrown.types.in.mref", refType.getThrownTypes());
2599 }
2600 }
2601 }
2603 public void visitParens(JCParens tree) {
2604 Type owntype = attribTree(tree.expr, env, resultInfo);
2605 result = check(tree, owntype, pkind(), resultInfo);
2606 Symbol sym = TreeInfo.symbol(tree);
2607 if (sym != null && (sym.kind&(TYP|PCK)) != 0)
2608 log.error(tree.pos(), "illegal.start.of.type");
2609 }
2611 public void visitAssign(JCAssign tree) {
2612 Type owntype = attribTree(tree.lhs, env.dup(tree), varInfo);
2613 Type capturedType = capture(owntype);
2614 attribExpr(tree.rhs, env, owntype);
2615 result = check(tree, capturedType, VAL, resultInfo);
2616 }
2618 public void visitAssignop(JCAssignOp tree) {
2619 // Attribute arguments.
2620 Type owntype = attribTree(tree.lhs, env, varInfo);
2621 Type operand = attribExpr(tree.rhs, env);
2622 // Find operator.
2623 Symbol operator = tree.operator = rs.resolveBinaryOperator(
2624 tree.pos(), tree.getTag().noAssignOp(), env,
2625 owntype, operand);
2627 if (operator.kind == MTH &&
2628 !owntype.isErroneous() &&
2629 !operand.isErroneous()) {
2630 chk.checkOperator(tree.pos(),
2631 (OperatorSymbol)operator,
2632 tree.getTag().noAssignOp(),
2633 owntype,
2634 operand);
2635 chk.checkDivZero(tree.rhs.pos(), operator, operand);
2636 chk.checkCastable(tree.rhs.pos(),
2637 operator.type.getReturnType(),
2638 owntype);
2639 }
2640 result = check(tree, owntype, VAL, resultInfo);
2641 }
2643 public void visitUnary(JCUnary tree) {
2644 // Attribute arguments.
2645 Type argtype = (tree.getTag().isIncOrDecUnaryOp())
2646 ? attribTree(tree.arg, env, varInfo)
2647 : chk.checkNonVoid(tree.arg.pos(), attribExpr(tree.arg, env));
2649 // Find operator.
2650 Symbol operator = tree.operator =
2651 rs.resolveUnaryOperator(tree.pos(), tree.getTag(), env, argtype);
2653 Type owntype = types.createErrorType(tree.type);
2654 if (operator.kind == MTH &&
2655 !argtype.isErroneous()) {
2656 owntype = (tree.getTag().isIncOrDecUnaryOp())
2657 ? tree.arg.type
2658 : operator.type.getReturnType();
2659 int opc = ((OperatorSymbol)operator).opcode;
2661 // If the argument is constant, fold it.
2662 if (argtype.constValue() != null) {
2663 Type ctype = cfolder.fold1(opc, argtype);
2664 if (ctype != null) {
2665 owntype = cfolder.coerce(ctype, owntype);
2667 // Remove constant types from arguments to
2668 // conserve space. The parser will fold concatenations
2669 // of string literals; the code here also
2670 // gets rid of intermediate results when some of the
2671 // operands are constant identifiers.
2672 if (tree.arg.type.tsym == syms.stringType.tsym) {
2673 tree.arg.type = syms.stringType;
2674 }
2675 }
2676 }
2677 }
2678 result = check(tree, owntype, VAL, resultInfo);
2679 }
2681 public void visitBinary(JCBinary tree) {
2682 // Attribute arguments.
2683 Type left = chk.checkNonVoid(tree.lhs.pos(), attribExpr(tree.lhs, env));
2684 Type right = chk.checkNonVoid(tree.lhs.pos(), attribExpr(tree.rhs, env));
2686 // Find operator.
2687 Symbol operator = tree.operator =
2688 rs.resolveBinaryOperator(tree.pos(), tree.getTag(), env, left, right);
2690 Type owntype = types.createErrorType(tree.type);
2691 if (operator.kind == MTH &&
2692 !left.isErroneous() &&
2693 !right.isErroneous()) {
2694 owntype = operator.type.getReturnType();
2695 int opc = chk.checkOperator(tree.lhs.pos(),
2696 (OperatorSymbol)operator,
2697 tree.getTag(),
2698 left,
2699 right);
2701 // If both arguments are constants, fold them.
2702 if (left.constValue() != null && right.constValue() != null) {
2703 Type ctype = cfolder.fold2(opc, left, right);
2704 if (ctype != null) {
2705 owntype = cfolder.coerce(ctype, owntype);
2707 // Remove constant types from arguments to
2708 // conserve space. The parser will fold concatenations
2709 // of string literals; the code here also
2710 // gets rid of intermediate results when some of the
2711 // operands are constant identifiers.
2712 if (tree.lhs.type.tsym == syms.stringType.tsym) {
2713 tree.lhs.type = syms.stringType;
2714 }
2715 if (tree.rhs.type.tsym == syms.stringType.tsym) {
2716 tree.rhs.type = syms.stringType;
2717 }
2718 }
2719 }
2721 // Check that argument types of a reference ==, != are
2722 // castable to each other, (JLS???).
2723 if ((opc == ByteCodes.if_acmpeq || opc == ByteCodes.if_acmpne)) {
2724 if (!types.isCastable(left, right, new Warner(tree.pos()))) {
2725 log.error(tree.pos(), "incomparable.types", left, right);
2726 }
2727 }
2729 chk.checkDivZero(tree.rhs.pos(), operator, right);
2730 }
2731 result = check(tree, owntype, VAL, resultInfo);
2732 }
2734 public void visitTypeCast(final JCTypeCast tree) {
2735 Type clazztype = attribType(tree.clazz, env);
2736 chk.validate(tree.clazz, env, false);
2737 //a fresh environment is required for 292 inference to work properly ---
2738 //see Infer.instantiatePolymorphicSignatureInstance()
2739 Env<AttrContext> localEnv = env.dup(tree);
2740 //should we propagate the target type?
2741 final ResultInfo castInfo;
2742 final boolean isPoly = TreeInfo.isPoly(tree.expr, tree);
2743 if (isPoly) {
2744 //expression is a poly - we need to propagate target type info
2745 castInfo = new ResultInfo(VAL, clazztype, new Check.NestedCheckContext(resultInfo.checkContext) {
2746 @Override
2747 public boolean compatible(Type found, Type req, Warner warn) {
2748 return types.isCastable(found, req, warn);
2749 }
2750 });
2751 } else {
2752 //standalone cast - target-type info is not propagated
2753 castInfo = unknownExprInfo;
2754 }
2755 Type exprtype = attribTree(tree.expr, localEnv, castInfo);
2756 Type owntype = isPoly ? clazztype : chk.checkCastable(tree.expr.pos(), exprtype, clazztype);
2757 if (exprtype.constValue() != null)
2758 owntype = cfolder.coerce(exprtype, owntype);
2759 result = check(tree, capture(owntype), VAL, resultInfo);
2760 if (!isPoly)
2761 chk.checkRedundantCast(localEnv, tree);
2762 }
2764 public void visitTypeTest(JCInstanceOf tree) {
2765 Type exprtype = chk.checkNullOrRefType(
2766 tree.expr.pos(), attribExpr(tree.expr, env));
2767 Type clazztype = chk.checkReifiableReferenceType(
2768 tree.clazz.pos(), attribType(tree.clazz, env));
2769 chk.validate(tree.clazz, env, false);
2770 chk.checkCastable(tree.expr.pos(), exprtype, clazztype);
2771 result = check(tree, syms.booleanType, VAL, resultInfo);
2772 }
2774 public void visitIndexed(JCArrayAccess tree) {
2775 Type owntype = types.createErrorType(tree.type);
2776 Type atype = attribExpr(tree.indexed, env);
2777 attribExpr(tree.index, env, syms.intType);
2778 if (types.isArray(atype))
2779 owntype = types.elemtype(atype);
2780 else if (!atype.hasTag(ERROR))
2781 log.error(tree.pos(), "array.req.but.found", atype);
2782 if ((pkind() & VAR) == 0) owntype = capture(owntype);
2783 result = check(tree, owntype, VAR, resultInfo);
2784 }
2786 public void visitIdent(JCIdent tree) {
2787 Symbol sym;
2789 // Find symbol
2790 if (pt().hasTag(METHOD) || pt().hasTag(FORALL)) {
2791 // If we are looking for a method, the prototype `pt' will be a
2792 // method type with the type of the call's arguments as parameters.
2793 env.info.pendingResolutionPhase = null;
2794 sym = rs.resolveMethod(tree.pos(), env, tree.name, pt().getParameterTypes(), pt().getTypeArguments());
2795 } else if (tree.sym != null && tree.sym.kind != VAR) {
2796 sym = tree.sym;
2797 } else {
2798 sym = rs.resolveIdent(tree.pos(), env, tree.name, pkind());
2799 }
2800 tree.sym = sym;
2802 // (1) Also find the environment current for the class where
2803 // sym is defined (`symEnv').
2804 // Only for pre-tiger versions (1.4 and earlier):
2805 // (2) Also determine whether we access symbol out of an anonymous
2806 // class in a this or super call. This is illegal for instance
2807 // members since such classes don't carry a this$n link.
2808 // (`noOuterThisPath').
2809 Env<AttrContext> symEnv = env;
2810 boolean noOuterThisPath = false;
2811 if (env.enclClass.sym.owner.kind != PCK && // we are in an inner class
2812 (sym.kind & (VAR | MTH | TYP)) != 0 &&
2813 sym.owner.kind == TYP &&
2814 tree.name != names._this && tree.name != names._super) {
2816 // Find environment in which identifier is defined.
2817 while (symEnv.outer != null &&
2818 !sym.isMemberOf(symEnv.enclClass.sym, types)) {
2819 if ((symEnv.enclClass.sym.flags() & NOOUTERTHIS) != 0)
2820 noOuterThisPath = !allowAnonOuterThis;
2821 symEnv = symEnv.outer;
2822 }
2823 }
2825 // If symbol is a variable, ...
2826 if (sym.kind == VAR) {
2827 VarSymbol v = (VarSymbol)sym;
2829 // ..., evaluate its initializer, if it has one, and check for
2830 // illegal forward reference.
2831 checkInit(tree, env, v, false);
2833 // If we are expecting a variable (as opposed to a value), check
2834 // that the variable is assignable in the current environment.
2835 if (pkind() == VAR)
2836 checkAssignable(tree.pos(), v, null, env);
2837 }
2839 // In a constructor body,
2840 // if symbol is a field or instance method, check that it is
2841 // not accessed before the supertype constructor is called.
2842 if ((symEnv.info.isSelfCall || noOuterThisPath) &&
2843 (sym.kind & (VAR | MTH)) != 0 &&
2844 sym.owner.kind == TYP &&
2845 (sym.flags() & STATIC) == 0) {
2846 chk.earlyRefError(tree.pos(), sym.kind == VAR ? sym : thisSym(tree.pos(), env));
2847 }
2848 Env<AttrContext> env1 = env;
2849 if (sym.kind != ERR && sym.kind != TYP && sym.owner != null && sym.owner != env1.enclClass.sym) {
2850 // If the found symbol is inaccessible, then it is
2851 // accessed through an enclosing instance. Locate this
2852 // enclosing instance:
2853 while (env1.outer != null && !rs.isAccessible(env, env1.enclClass.sym.type, sym))
2854 env1 = env1.outer;
2855 }
2856 result = checkId(tree, env1.enclClass.sym.type, sym, env, resultInfo);
2857 }
2859 public void visitSelect(JCFieldAccess tree) {
2860 // Determine the expected kind of the qualifier expression.
2861 int skind = 0;
2862 if (tree.name == names._this || tree.name == names._super ||
2863 tree.name == names._class)
2864 {
2865 skind = TYP;
2866 } else {
2867 if ((pkind() & PCK) != 0) skind = skind | PCK;
2868 if ((pkind() & TYP) != 0) skind = skind | TYP | PCK;
2869 if ((pkind() & (VAL | MTH)) != 0) skind = skind | VAL | TYP;
2870 }
2872 // Attribute the qualifier expression, and determine its symbol (if any).
2873 Type site = attribTree(tree.selected, env, new ResultInfo(skind, Infer.anyPoly));
2874 if ((pkind() & (PCK | TYP)) == 0)
2875 site = capture(site); // Capture field access
2877 // don't allow T.class T[].class, etc
2878 if (skind == TYP) {
2879 Type elt = site;
2880 while (elt.hasTag(ARRAY))
2881 elt = ((ArrayType)elt).elemtype;
2882 if (elt.hasTag(TYPEVAR)) {
2883 log.error(tree.pos(), "type.var.cant.be.deref");
2884 result = types.createErrorType(tree.type);
2885 return;
2886 }
2887 }
2889 // If qualifier symbol is a type or `super', assert `selectSuper'
2890 // for the selection. This is relevant for determining whether
2891 // protected symbols are accessible.
2892 Symbol sitesym = TreeInfo.symbol(tree.selected);
2893 boolean selectSuperPrev = env.info.selectSuper;
2894 env.info.selectSuper =
2895 sitesym != null &&
2896 sitesym.name == names._super;
2898 // Determine the symbol represented by the selection.
2899 env.info.pendingResolutionPhase = null;
2900 Symbol sym = selectSym(tree, sitesym, site, env, resultInfo);
2901 if (sym.exists() && !isType(sym) && (pkind() & (PCK | TYP)) != 0) {
2902 site = capture(site);
2903 sym = selectSym(tree, sitesym, site, env, resultInfo);
2904 }
2905 boolean varArgs = env.info.lastResolveVarargs();
2906 tree.sym = sym;
2908 if (site.hasTag(TYPEVAR) && !isType(sym) && sym.kind != ERR) {
2909 while (site.hasTag(TYPEVAR)) site = site.getUpperBound();
2910 site = capture(site);
2911 }
2913 // If that symbol is a variable, ...
2914 if (sym.kind == VAR) {
2915 VarSymbol v = (VarSymbol)sym;
2917 // ..., evaluate its initializer, if it has one, and check for
2918 // illegal forward reference.
2919 checkInit(tree, env, v, true);
2921 // If we are expecting a variable (as opposed to a value), check
2922 // that the variable is assignable in the current environment.
2923 if (pkind() == VAR)
2924 checkAssignable(tree.pos(), v, tree.selected, env);
2925 }
2927 if (sitesym != null &&
2928 sitesym.kind == VAR &&
2929 ((VarSymbol)sitesym).isResourceVariable() &&
2930 sym.kind == MTH &&
2931 sym.name.equals(names.close) &&
2932 sym.overrides(syms.autoCloseableClose, sitesym.type.tsym, types, true) &&
2933 env.info.lint.isEnabled(LintCategory.TRY)) {
2934 log.warning(LintCategory.TRY, tree, "try.explicit.close.call");
2935 }
2937 // Disallow selecting a type from an expression
2938 if (isType(sym) && (sitesym==null || (sitesym.kind&(TYP|PCK)) == 0)) {
2939 tree.type = check(tree.selected, pt(),
2940 sitesym == null ? VAL : sitesym.kind, new ResultInfo(TYP|PCK, pt()));
2941 }
2943 if (isType(sitesym)) {
2944 if (sym.name == names._this) {
2945 // If `C' is the currently compiled class, check that
2946 // C.this' does not appear in a call to a super(...)
2947 if (env.info.isSelfCall &&
2948 site.tsym == env.enclClass.sym) {
2949 chk.earlyRefError(tree.pos(), sym);
2950 }
2951 } else {
2952 // Check if type-qualified fields or methods are static (JLS)
2953 if ((sym.flags() & STATIC) == 0 &&
2954 !env.next.tree.hasTag(REFERENCE) &&
2955 sym.name != names._super &&
2956 (sym.kind == VAR || sym.kind == MTH)) {
2957 rs.accessBase(rs.new StaticError(sym),
2958 tree.pos(), site, sym.name, true);
2959 }
2960 }
2961 } else if (sym.kind != ERR && (sym.flags() & STATIC) != 0 && sym.name != names._class) {
2962 // If the qualified item is not a type and the selected item is static, report
2963 // a warning. Make allowance for the class of an array type e.g. Object[].class)
2964 chk.warnStatic(tree, "static.not.qualified.by.type", Kinds.kindName(sym.kind), sym.owner);
2965 }
2967 // If we are selecting an instance member via a `super', ...
2968 if (env.info.selectSuper && (sym.flags() & STATIC) == 0) {
2970 // Check that super-qualified symbols are not abstract (JLS)
2971 rs.checkNonAbstract(tree.pos(), sym);
2973 if (site.isRaw()) {
2974 // Determine argument types for site.
2975 Type site1 = types.asSuper(env.enclClass.sym.type, site.tsym);
2976 if (site1 != null) site = site1;
2977 }
2978 }
2980 env.info.selectSuper = selectSuperPrev;
2981 result = checkId(tree, site, sym, env, resultInfo);
2982 }
2983 //where
2984 /** Determine symbol referenced by a Select expression,
2985 *
2986 * @param tree The select tree.
2987 * @param site The type of the selected expression,
2988 * @param env The current environment.
2989 * @param resultInfo The current result.
2990 */
2991 private Symbol selectSym(JCFieldAccess tree,
2992 Symbol location,
2993 Type site,
2994 Env<AttrContext> env,
2995 ResultInfo resultInfo) {
2996 DiagnosticPosition pos = tree.pos();
2997 Name name = tree.name;
2998 switch (site.getTag()) {
2999 case PACKAGE:
3000 return rs.accessBase(
3001 rs.findIdentInPackage(env, site.tsym, name, resultInfo.pkind),
3002 pos, location, site, name, true);
3003 case ARRAY:
3004 case CLASS:
3005 if (resultInfo.pt.hasTag(METHOD) || resultInfo.pt.hasTag(FORALL)) {
3006 return rs.resolveQualifiedMethod(
3007 pos, env, location, site, name, resultInfo.pt.getParameterTypes(), resultInfo.pt.getTypeArguments());
3008 } else if (name == names._this || name == names._super) {
3009 return rs.resolveSelf(pos, env, site.tsym, name);
3010 } else if (name == names._class) {
3011 // In this case, we have already made sure in
3012 // visitSelect that qualifier expression is a type.
3013 Type t = syms.classType;
3014 List<Type> typeargs = allowGenerics
3015 ? List.of(types.erasure(site))
3016 : List.<Type>nil();
3017 t = new ClassType(t.getEnclosingType(), typeargs, t.tsym);
3018 return new VarSymbol(
3019 STATIC | PUBLIC | FINAL, names._class, t, site.tsym);
3020 } else {
3021 // We are seeing a plain identifier as selector.
3022 Symbol sym = rs.findIdentInType(env, site, name, resultInfo.pkind);
3023 if ((resultInfo.pkind & ERRONEOUS) == 0)
3024 sym = rs.accessBase(sym, pos, location, site, name, true);
3025 return sym;
3026 }
3027 case WILDCARD:
3028 throw new AssertionError(tree);
3029 case TYPEVAR:
3030 // Normally, site.getUpperBound() shouldn't be null.
3031 // It should only happen during memberEnter/attribBase
3032 // when determining the super type which *must* beac
3033 // done before attributing the type variables. In
3034 // other words, we are seeing this illegal program:
3035 // class B<T> extends A<T.foo> {}
3036 Symbol sym = (site.getUpperBound() != null)
3037 ? selectSym(tree, location, capture(site.getUpperBound()), env, resultInfo)
3038 : null;
3039 if (sym == null) {
3040 log.error(pos, "type.var.cant.be.deref");
3041 return syms.errSymbol;
3042 } else {
3043 Symbol sym2 = (sym.flags() & Flags.PRIVATE) != 0 ?
3044 rs.new AccessError(env, site, sym) :
3045 sym;
3046 rs.accessBase(sym2, pos, location, site, name, true);
3047 return sym;
3048 }
3049 case ERROR:
3050 // preserve identifier names through errors
3051 return types.createErrorType(name, site.tsym, site).tsym;
3052 default:
3053 // The qualifier expression is of a primitive type -- only
3054 // .class is allowed for these.
3055 if (name == names._class) {
3056 // In this case, we have already made sure in Select that
3057 // qualifier expression is a type.
3058 Type t = syms.classType;
3059 Type arg = types.boxedClass(site).type;
3060 t = new ClassType(t.getEnclosingType(), List.of(arg), t.tsym);
3061 return new VarSymbol(
3062 STATIC | PUBLIC | FINAL, names._class, t, site.tsym);
3063 } else {
3064 log.error(pos, "cant.deref", site);
3065 return syms.errSymbol;
3066 }
3067 }
3068 }
3070 /** Determine type of identifier or select expression and check that
3071 * (1) the referenced symbol is not deprecated
3072 * (2) the symbol's type is safe (@see checkSafe)
3073 * (3) if symbol is a variable, check that its type and kind are
3074 * compatible with the prototype and protokind.
3075 * (4) if symbol is an instance field of a raw type,
3076 * which is being assigned to, issue an unchecked warning if its
3077 * type changes under erasure.
3078 * (5) if symbol is an instance method of a raw type, issue an
3079 * unchecked warning if its argument types change under erasure.
3080 * If checks succeed:
3081 * If symbol is a constant, return its constant type
3082 * else if symbol is a method, return its result type
3083 * otherwise return its type.
3084 * Otherwise return errType.
3085 *
3086 * @param tree The syntax tree representing the identifier
3087 * @param site If this is a select, the type of the selected
3088 * expression, otherwise the type of the current class.
3089 * @param sym The symbol representing the identifier.
3090 * @param env The current environment.
3091 * @param resultInfo The expected result
3092 */
3093 Type checkId(JCTree tree,
3094 Type site,
3095 Symbol sym,
3096 Env<AttrContext> env,
3097 ResultInfo resultInfo) {
3098 return (resultInfo.pt.hasTag(FORALL) || resultInfo.pt.hasTag(METHOD)) ?
3099 checkMethodId(tree, site, sym, env, resultInfo) :
3100 checkIdInternal(tree, site, sym, resultInfo.pt, env, resultInfo);
3101 }
3103 Type checkMethodId(JCTree tree,
3104 Type site,
3105 Symbol sym,
3106 Env<AttrContext> env,
3107 ResultInfo resultInfo) {
3108 boolean isPolymorhicSignature =
3109 sym.kind == MTH && ((MethodSymbol)sym.baseSymbol()).isSignaturePolymorphic(types);
3110 return isPolymorhicSignature ?
3111 checkSigPolyMethodId(tree, site, sym, env, resultInfo) :
3112 checkMethodIdInternal(tree, site, sym, env, resultInfo);
3113 }
3115 Type checkSigPolyMethodId(JCTree tree,
3116 Type site,
3117 Symbol sym,
3118 Env<AttrContext> env,
3119 ResultInfo resultInfo) {
3120 //recover original symbol for signature polymorphic methods
3121 checkMethodIdInternal(tree, site, sym.baseSymbol(), env, resultInfo);
3122 env.info.pendingResolutionPhase = Resolve.MethodResolutionPhase.BASIC;
3123 return sym.type;
3124 }
3126 Type checkMethodIdInternal(JCTree tree,
3127 Type site,
3128 Symbol sym,
3129 Env<AttrContext> env,
3130 ResultInfo resultInfo) {
3131 Type pt = resultInfo.pt.map(deferredAttr.new RecoveryDeferredTypeMap(AttrMode.SPECULATIVE, sym, env.info.pendingResolutionPhase));
3132 Type owntype = checkIdInternal(tree, site, sym, pt, env, resultInfo);
3133 resultInfo.pt.map(deferredAttr.new RecoveryDeferredTypeMap(AttrMode.CHECK, sym, env.info.pendingResolutionPhase));
3134 return owntype;
3135 }
3137 Type checkIdInternal(JCTree tree,
3138 Type site,
3139 Symbol sym,
3140 Type pt,
3141 Env<AttrContext> env,
3142 ResultInfo resultInfo) {
3143 if (pt.isErroneous()) {
3144 return types.createErrorType(site);
3145 }
3146 Type owntype; // The computed type of this identifier occurrence.
3147 switch (sym.kind) {
3148 case TYP:
3149 // For types, the computed type equals the symbol's type,
3150 // except for two situations:
3151 owntype = sym.type;
3152 if (owntype.hasTag(CLASS)) {
3153 chk.checkForBadAuxiliaryClassAccess(tree.pos(), env, (ClassSymbol)sym);
3154 Type ownOuter = owntype.getEnclosingType();
3156 // (a) If the symbol's type is parameterized, erase it
3157 // because no type parameters were given.
3158 // We recover generic outer type later in visitTypeApply.
3159 if (owntype.tsym.type.getTypeArguments().nonEmpty()) {
3160 owntype = types.erasure(owntype);
3161 }
3163 // (b) If the symbol's type is an inner class, then
3164 // we have to interpret its outer type as a superclass
3165 // of the site type. Example:
3166 //
3167 // class Tree<A> { class Visitor { ... } }
3168 // class PointTree extends Tree<Point> { ... }
3169 // ...PointTree.Visitor...
3170 //
3171 // Then the type of the last expression above is
3172 // Tree<Point>.Visitor.
3173 else if (ownOuter.hasTag(CLASS) && site != ownOuter) {
3174 Type normOuter = site;
3175 if (normOuter.hasTag(CLASS))
3176 normOuter = types.asEnclosingSuper(site, ownOuter.tsym);
3177 if (normOuter == null) // perhaps from an import
3178 normOuter = types.erasure(ownOuter);
3179 if (normOuter != ownOuter)
3180 owntype = new ClassType(
3181 normOuter, List.<Type>nil(), owntype.tsym);
3182 }
3183 }
3184 break;
3185 case VAR:
3186 VarSymbol v = (VarSymbol)sym;
3187 // Test (4): if symbol is an instance field of a raw type,
3188 // which is being assigned to, issue an unchecked warning if
3189 // its type changes under erasure.
3190 if (allowGenerics &&
3191 resultInfo.pkind == VAR &&
3192 v.owner.kind == TYP &&
3193 (v.flags() & STATIC) == 0 &&
3194 (site.hasTag(CLASS) || site.hasTag(TYPEVAR))) {
3195 Type s = types.asOuterSuper(site, v.owner);
3196 if (s != null &&
3197 s.isRaw() &&
3198 !types.isSameType(v.type, v.erasure(types))) {
3199 chk.warnUnchecked(tree.pos(),
3200 "unchecked.assign.to.var",
3201 v, s);
3202 }
3203 }
3204 // The computed type of a variable is the type of the
3205 // variable symbol, taken as a member of the site type.
3206 owntype = (sym.owner.kind == TYP &&
3207 sym.name != names._this && sym.name != names._super)
3208 ? types.memberType(site, sym)
3209 : sym.type;
3211 // If the variable is a constant, record constant value in
3212 // computed type.
3213 if (v.getConstValue() != null && isStaticReference(tree))
3214 owntype = owntype.constType(v.getConstValue());
3216 if (resultInfo.pkind == VAL) {
3217 owntype = capture(owntype); // capture "names as expressions"
3218 }
3219 break;
3220 case MTH: {
3221 owntype = checkMethod(site, sym,
3222 new ResultInfo(VAL, resultInfo.pt.getReturnType(), resultInfo.checkContext),
3223 env, TreeInfo.args(env.tree), resultInfo.pt.getParameterTypes(),
3224 resultInfo.pt.getTypeArguments());
3225 break;
3226 }
3227 case PCK: case ERR:
3228 owntype = sym.type;
3229 break;
3230 default:
3231 throw new AssertionError("unexpected kind: " + sym.kind +
3232 " in tree " + tree);
3233 }
3235 // Test (1): emit a `deprecation' warning if symbol is deprecated.
3236 // (for constructors, the error was given when the constructor was
3237 // resolved)
3239 if (sym.name != names.init) {
3240 chk.checkDeprecated(tree.pos(), env.info.scope.owner, sym);
3241 chk.checkSunAPI(tree.pos(), sym);
3242 }
3244 // Test (3): if symbol is a variable, check that its type and
3245 // kind are compatible with the prototype and protokind.
3246 return check(tree, owntype, sym.kind, resultInfo);
3247 }
3249 /** Check that variable is initialized and evaluate the variable's
3250 * initializer, if not yet done. Also check that variable is not
3251 * referenced before it is defined.
3252 * @param tree The tree making up the variable reference.
3253 * @param env The current environment.
3254 * @param v The variable's symbol.
3255 */
3256 private void checkInit(JCTree tree,
3257 Env<AttrContext> env,
3258 VarSymbol v,
3259 boolean onlyWarning) {
3260 // System.err.println(v + " " + ((v.flags() & STATIC) != 0) + " " +
3261 // tree.pos + " " + v.pos + " " +
3262 // Resolve.isStatic(env));//DEBUG
3264 // A forward reference is diagnosed if the declaration position
3265 // of the variable is greater than the current tree position
3266 // and the tree and variable definition occur in the same class
3267 // definition. Note that writes don't count as references.
3268 // This check applies only to class and instance
3269 // variables. Local variables follow different scope rules,
3270 // and are subject to definite assignment checking.
3271 if ((env.info.enclVar == v || v.pos > tree.pos) &&
3272 v.owner.kind == TYP &&
3273 canOwnInitializer(owner(env)) &&
3274 v.owner == env.info.scope.owner.enclClass() &&
3275 ((v.flags() & STATIC) != 0) == Resolve.isStatic(env) &&
3276 (!env.tree.hasTag(ASSIGN) ||
3277 TreeInfo.skipParens(((JCAssign) env.tree).lhs) != tree)) {
3278 String suffix = (env.info.enclVar == v) ?
3279 "self.ref" : "forward.ref";
3280 if (!onlyWarning || isStaticEnumField(v)) {
3281 log.error(tree.pos(), "illegal." + suffix);
3282 } else if (useBeforeDeclarationWarning) {
3283 log.warning(tree.pos(), suffix, v);
3284 }
3285 }
3287 v.getConstValue(); // ensure initializer is evaluated
3289 checkEnumInitializer(tree, env, v);
3290 }
3292 /**
3293 * Check for illegal references to static members of enum. In
3294 * an enum type, constructors and initializers may not
3295 * reference its static members unless they are constant.
3296 *
3297 * @param tree The tree making up the variable reference.
3298 * @param env The current environment.
3299 * @param v The variable's symbol.
3300 * @jls section 8.9 Enums
3301 */
3302 private void checkEnumInitializer(JCTree tree, Env<AttrContext> env, VarSymbol v) {
3303 // JLS:
3304 //
3305 // "It is a compile-time error to reference a static field
3306 // of an enum type that is not a compile-time constant
3307 // (15.28) from constructors, instance initializer blocks,
3308 // or instance variable initializer expressions of that
3309 // type. It is a compile-time error for the constructors,
3310 // instance initializer blocks, or instance variable
3311 // initializer expressions of an enum constant e to refer
3312 // to itself or to an enum constant of the same type that
3313 // is declared to the right of e."
3314 if (isStaticEnumField(v)) {
3315 ClassSymbol enclClass = env.info.scope.owner.enclClass();
3317 if (enclClass == null || enclClass.owner == null)
3318 return;
3320 // See if the enclosing class is the enum (or a
3321 // subclass thereof) declaring v. If not, this
3322 // reference is OK.
3323 if (v.owner != enclClass && !types.isSubtype(enclClass.type, v.owner.type))
3324 return;
3326 // If the reference isn't from an initializer, then
3327 // the reference is OK.
3328 if (!Resolve.isInitializer(env))
3329 return;
3331 log.error(tree.pos(), "illegal.enum.static.ref");
3332 }
3333 }
3335 /** Is the given symbol a static, non-constant field of an Enum?
3336 * Note: enum literals should not be regarded as such
3337 */
3338 private boolean isStaticEnumField(VarSymbol v) {
3339 return Flags.isEnum(v.owner) &&
3340 Flags.isStatic(v) &&
3341 !Flags.isConstant(v) &&
3342 v.name != names._class;
3343 }
3345 /** Can the given symbol be the owner of code which forms part
3346 * if class initialization? This is the case if the symbol is
3347 * a type or field, or if the symbol is the synthetic method.
3348 * owning a block.
3349 */
3350 private boolean canOwnInitializer(Symbol sym) {
3351 return
3352 (sym.kind & (VAR | TYP)) != 0 ||
3353 (sym.kind == MTH && (sym.flags() & BLOCK) != 0);
3354 }
3356 Warner noteWarner = new Warner();
3358 /**
3359 * Check that method arguments conform to its instantiation.
3360 **/
3361 public Type checkMethod(Type site,
3362 Symbol sym,
3363 ResultInfo resultInfo,
3364 Env<AttrContext> env,
3365 final List<JCExpression> argtrees,
3366 List<Type> argtypes,
3367 List<Type> typeargtypes) {
3368 // Test (5): if symbol is an instance method of a raw type, issue
3369 // an unchecked warning if its argument types change under erasure.
3370 if (allowGenerics &&
3371 (sym.flags() & STATIC) == 0 &&
3372 (site.hasTag(CLASS) || site.hasTag(TYPEVAR))) {
3373 Type s = types.asOuterSuper(site, sym.owner);
3374 if (s != null && s.isRaw() &&
3375 !types.isSameTypes(sym.type.getParameterTypes(),
3376 sym.erasure(types).getParameterTypes())) {
3377 chk.warnUnchecked(env.tree.pos(),
3378 "unchecked.call.mbr.of.raw.type",
3379 sym, s);
3380 }
3381 }
3383 if (env.info.defaultSuperCallSite != null) {
3384 for (Type sup : types.interfaces(env.enclClass.type).prepend(types.supertype((env.enclClass.type)))) {
3385 if (!sup.tsym.isSubClass(sym.enclClass(), types) ||
3386 types.isSameType(sup, env.info.defaultSuperCallSite)) continue;
3387 List<MethodSymbol> icand_sup =
3388 types.interfaceCandidates(sup, (MethodSymbol)sym);
3389 if (icand_sup.nonEmpty() &&
3390 icand_sup.head != sym &&
3391 icand_sup.head.overrides(sym, icand_sup.head.enclClass(), types, true)) {
3392 log.error(env.tree.pos(), "illegal.default.super.call", env.info.defaultSuperCallSite,
3393 diags.fragment("overridden.default", sym, sup));
3394 break;
3395 }
3396 }
3397 env.info.defaultSuperCallSite = null;
3398 }
3400 // Compute the identifier's instantiated type.
3401 // For methods, we need to compute the instance type by
3402 // Resolve.instantiate from the symbol's type as well as
3403 // any type arguments and value arguments.
3404 noteWarner.clear();
3405 try {
3406 Type owntype = rs.checkMethod(
3407 env,
3408 site,
3409 sym,
3410 resultInfo,
3411 argtypes,
3412 typeargtypes,
3413 noteWarner);
3415 return chk.checkMethod(owntype, sym, env, argtrees, argtypes, env.info.lastResolveVarargs(),
3416 noteWarner.hasNonSilentLint(LintCategory.UNCHECKED));
3417 } catch (Infer.InferenceException ex) {
3418 //invalid target type - propagate exception outwards or report error
3419 //depending on the current check context
3420 resultInfo.checkContext.report(env.tree.pos(), ex.getDiagnostic());
3421 return types.createErrorType(site);
3422 } catch (Resolve.InapplicableMethodException ex) {
3423 Assert.error(ex.getDiagnostic().getMessage(Locale.getDefault()));
3424 return null;
3425 }
3426 }
3428 public void visitLiteral(JCLiteral tree) {
3429 result = check(
3430 tree, litType(tree.typetag).constType(tree.value), VAL, resultInfo);
3431 }
3432 //where
3433 /** Return the type of a literal with given type tag.
3434 */
3435 Type litType(TypeTag tag) {
3436 return (tag == CLASS) ? syms.stringType : syms.typeOfTag[tag.ordinal()];
3437 }
3439 public void visitTypeIdent(JCPrimitiveTypeTree tree) {
3440 result = check(tree, syms.typeOfTag[tree.typetag.ordinal()], TYP, resultInfo);
3441 }
3443 public void visitTypeArray(JCArrayTypeTree tree) {
3444 Type etype = attribType(tree.elemtype, env);
3445 Type type = new ArrayType(etype, syms.arrayClass);
3446 result = check(tree, type, TYP, resultInfo);
3447 }
3449 /** Visitor method for parameterized types.
3450 * Bound checking is left until later, since types are attributed
3451 * before supertype structure is completely known
3452 */
3453 public void visitTypeApply(JCTypeApply tree) {
3454 Type owntype = types.createErrorType(tree.type);
3456 // Attribute functor part of application and make sure it's a class.
3457 Type clazztype = chk.checkClassType(tree.clazz.pos(), attribType(tree.clazz, env));
3459 // Attribute type parameters
3460 List<Type> actuals = attribTypes(tree.arguments, env);
3462 if (clazztype.hasTag(CLASS)) {
3463 List<Type> formals = clazztype.tsym.type.getTypeArguments();
3464 if (actuals.isEmpty()) //diamond
3465 actuals = formals;
3467 if (actuals.length() == formals.length()) {
3468 List<Type> a = actuals;
3469 List<Type> f = formals;
3470 while (a.nonEmpty()) {
3471 a.head = a.head.withTypeVar(f.head);
3472 a = a.tail;
3473 f = f.tail;
3474 }
3475 // Compute the proper generic outer
3476 Type clazzOuter = clazztype.getEnclosingType();
3477 if (clazzOuter.hasTag(CLASS)) {
3478 Type site;
3479 JCExpression clazz = TreeInfo.typeIn(tree.clazz);
3480 if (clazz.hasTag(IDENT)) {
3481 site = env.enclClass.sym.type;
3482 } else if (clazz.hasTag(SELECT)) {
3483 site = ((JCFieldAccess) clazz).selected.type;
3484 } else throw new AssertionError(""+tree);
3485 if (clazzOuter.hasTag(CLASS) && site != clazzOuter) {
3486 if (site.hasTag(CLASS))
3487 site = types.asOuterSuper(site, clazzOuter.tsym);
3488 if (site == null)
3489 site = types.erasure(clazzOuter);
3490 clazzOuter = site;
3491 }
3492 }
3493 owntype = new ClassType(clazzOuter, actuals, clazztype.tsym);
3494 } else {
3495 if (formals.length() != 0) {
3496 log.error(tree.pos(), "wrong.number.type.args",
3497 Integer.toString(formals.length()));
3498 } else {
3499 log.error(tree.pos(), "type.doesnt.take.params", clazztype.tsym);
3500 }
3501 owntype = types.createErrorType(tree.type);
3502 }
3503 }
3504 result = check(tree, owntype, TYP, resultInfo);
3505 }
3507 public void visitTypeUnion(JCTypeUnion tree) {
3508 ListBuffer<Type> multicatchTypes = ListBuffer.lb();
3509 ListBuffer<Type> all_multicatchTypes = null; // lazy, only if needed
3510 for (JCExpression typeTree : tree.alternatives) {
3511 Type ctype = attribType(typeTree, env);
3512 ctype = chk.checkType(typeTree.pos(),
3513 chk.checkClassType(typeTree.pos(), ctype),
3514 syms.throwableType);
3515 if (!ctype.isErroneous()) {
3516 //check that alternatives of a union type are pairwise
3517 //unrelated w.r.t. subtyping
3518 if (chk.intersects(ctype, multicatchTypes.toList())) {
3519 for (Type t : multicatchTypes) {
3520 boolean sub = types.isSubtype(ctype, t);
3521 boolean sup = types.isSubtype(t, ctype);
3522 if (sub || sup) {
3523 //assume 'a' <: 'b'
3524 Type a = sub ? ctype : t;
3525 Type b = sub ? t : ctype;
3526 log.error(typeTree.pos(), "multicatch.types.must.be.disjoint", a, b);
3527 }
3528 }
3529 }
3530 multicatchTypes.append(ctype);
3531 if (all_multicatchTypes != null)
3532 all_multicatchTypes.append(ctype);
3533 } else {
3534 if (all_multicatchTypes == null) {
3535 all_multicatchTypes = ListBuffer.lb();
3536 all_multicatchTypes.appendList(multicatchTypes);
3537 }
3538 all_multicatchTypes.append(ctype);
3539 }
3540 }
3541 Type t = check(tree, types.lub(multicatchTypes.toList()), TYP, resultInfo);
3542 if (t.hasTag(CLASS)) {
3543 List<Type> alternatives =
3544 ((all_multicatchTypes == null) ? multicatchTypes : all_multicatchTypes).toList();
3545 t = new UnionClassType((ClassType) t, alternatives);
3546 }
3547 tree.type = result = t;
3548 }
3550 public void visitTypeParameter(JCTypeParameter tree) {
3551 TypeVar a = (TypeVar)tree.type;
3552 Set<Type> boundSet = new HashSet<Type>();
3553 if (a.bound.isErroneous())
3554 return;
3555 List<Type> bs = types.getBounds(a);
3556 if (tree.bounds.nonEmpty()) {
3557 // accept class or interface or typevar as first bound.
3558 Type b = checkBase(bs.head, tree.bounds.head, env, false, false, false);
3559 boundSet.add(types.erasure(b));
3560 if (b.isErroneous()) {
3561 a.bound = b;
3562 }
3563 else if (b.hasTag(TYPEVAR)) {
3564 // if first bound was a typevar, do not accept further bounds.
3565 if (tree.bounds.tail.nonEmpty()) {
3566 log.error(tree.bounds.tail.head.pos(),
3567 "type.var.may.not.be.followed.by.other.bounds");
3568 tree.bounds = List.of(tree.bounds.head);
3569 a.bound = bs.head;
3570 }
3571 } else {
3572 // if first bound was a class or interface, accept only interfaces
3573 // as further bounds.
3574 for (JCExpression bound : tree.bounds.tail) {
3575 bs = bs.tail;
3576 Type i = checkBase(bs.head, bound, env, false, true, false);
3577 if (i.isErroneous())
3578 a.bound = i;
3579 else if (i.hasTag(CLASS))
3580 chk.checkNotRepeated(bound.pos(), types.erasure(i), boundSet);
3581 }
3582 }
3583 }
3584 bs = types.getBounds(a);
3586 // in case of multiple bounds ...
3587 if (bs.length() > 1) {
3588 // ... the variable's bound is a class type flagged COMPOUND
3589 // (see comment for TypeVar.bound).
3590 // In this case, generate a class tree that represents the
3591 // bound class, ...
3592 JCExpression extending;
3593 List<JCExpression> implementing;
3594 if ((bs.head.tsym.flags() & INTERFACE) == 0) {
3595 extending = tree.bounds.head;
3596 implementing = tree.bounds.tail;
3597 } else {
3598 extending = null;
3599 implementing = tree.bounds;
3600 }
3601 JCClassDecl cd = make.at(tree.pos).ClassDef(
3602 make.Modifiers(PUBLIC | ABSTRACT),
3603 tree.name, List.<JCTypeParameter>nil(),
3604 extending, implementing, List.<JCTree>nil());
3606 ClassSymbol c = (ClassSymbol)a.getUpperBound().tsym;
3607 Assert.check((c.flags() & COMPOUND) != 0);
3608 cd.sym = c;
3609 c.sourcefile = env.toplevel.sourcefile;
3611 // ... and attribute the bound class
3612 c.flags_field |= UNATTRIBUTED;
3613 Env<AttrContext> cenv = enter.classEnv(cd, env);
3614 enter.typeEnvs.put(c, cenv);
3615 }
3616 }
3619 public void visitWildcard(JCWildcard tree) {
3620 //- System.err.println("visitWildcard("+tree+");");//DEBUG
3621 Type type = (tree.kind.kind == BoundKind.UNBOUND)
3622 ? syms.objectType
3623 : attribType(tree.inner, env);
3624 result = check(tree, new WildcardType(chk.checkRefType(tree.pos(), type),
3625 tree.kind.kind,
3626 syms.boundClass),
3627 TYP, resultInfo);
3628 }
3630 public void visitAnnotation(JCAnnotation tree) {
3631 log.error(tree.pos(), "annotation.not.valid.for.type", pt());
3632 result = tree.type = syms.errType;
3633 }
3635 public void visitErroneous(JCErroneous tree) {
3636 if (tree.errs != null)
3637 for (JCTree err : tree.errs)
3638 attribTree(err, env, new ResultInfo(ERR, pt()));
3639 result = tree.type = syms.errType;
3640 }
3642 /** Default visitor method for all other trees.
3643 */
3644 public void visitTree(JCTree tree) {
3645 throw new AssertionError();
3646 }
3648 /**
3649 * Attribute an env for either a top level tree or class declaration.
3650 */
3651 public void attrib(Env<AttrContext> env) {
3652 if (env.tree.hasTag(TOPLEVEL))
3653 attribTopLevel(env);
3654 else
3655 attribClass(env.tree.pos(), env.enclClass.sym);
3656 }
3658 /**
3659 * Attribute a top level tree. These trees are encountered when the
3660 * package declaration has annotations.
3661 */
3662 public void attribTopLevel(Env<AttrContext> env) {
3663 JCCompilationUnit toplevel = env.toplevel;
3664 try {
3665 annotate.flush();
3666 chk.validateAnnotations(toplevel.packageAnnotations, toplevel.packge);
3667 } catch (CompletionFailure ex) {
3668 chk.completionError(toplevel.pos(), ex);
3669 }
3670 }
3672 /** Main method: attribute class definition associated with given class symbol.
3673 * reporting completion failures at the given position.
3674 * @param pos The source position at which completion errors are to be
3675 * reported.
3676 * @param c The class symbol whose definition will be attributed.
3677 */
3678 public void attribClass(DiagnosticPosition pos, ClassSymbol c) {
3679 try {
3680 annotate.flush();
3681 attribClass(c);
3682 } catch (CompletionFailure ex) {
3683 chk.completionError(pos, ex);
3684 }
3685 }
3687 /** Attribute class definition associated with given class symbol.
3688 * @param c The class symbol whose definition will be attributed.
3689 */
3690 void attribClass(ClassSymbol c) throws CompletionFailure {
3691 if (c.type.hasTag(ERROR)) return;
3693 // Check for cycles in the inheritance graph, which can arise from
3694 // ill-formed class files.
3695 chk.checkNonCyclic(null, c.type);
3697 Type st = types.supertype(c.type);
3698 if ((c.flags_field & Flags.COMPOUND) == 0) {
3699 // First, attribute superclass.
3700 if (st.hasTag(CLASS))
3701 attribClass((ClassSymbol)st.tsym);
3703 // Next attribute owner, if it is a class.
3704 if (c.owner.kind == TYP && c.owner.type.hasTag(CLASS))
3705 attribClass((ClassSymbol)c.owner);
3706 }
3708 // The previous operations might have attributed the current class
3709 // if there was a cycle. So we test first whether the class is still
3710 // UNATTRIBUTED.
3711 if ((c.flags_field & UNATTRIBUTED) != 0) {
3712 c.flags_field &= ~UNATTRIBUTED;
3714 // Get environment current at the point of class definition.
3715 Env<AttrContext> env = enter.typeEnvs.get(c);
3717 // The info.lint field in the envs stored in enter.typeEnvs is deliberately uninitialized,
3718 // because the annotations were not available at the time the env was created. Therefore,
3719 // we look up the environment chain for the first enclosing environment for which the
3720 // lint value is set. Typically, this is the parent env, but might be further if there
3721 // are any envs created as a result of TypeParameter nodes.
3722 Env<AttrContext> lintEnv = env;
3723 while (lintEnv.info.lint == null)
3724 lintEnv = lintEnv.next;
3726 // Having found the enclosing lint value, we can initialize the lint value for this class
3727 env.info.lint = lintEnv.info.lint.augment(c.annotations, c.flags());
3729 Lint prevLint = chk.setLint(env.info.lint);
3730 JavaFileObject prev = log.useSource(c.sourcefile);
3731 ResultInfo prevReturnRes = env.info.returnResult;
3733 try {
3734 env.info.returnResult = null;
3735 // java.lang.Enum may not be subclassed by a non-enum
3736 if (st.tsym == syms.enumSym &&
3737 ((c.flags_field & (Flags.ENUM|Flags.COMPOUND)) == 0))
3738 log.error(env.tree.pos(), "enum.no.subclassing");
3740 // Enums may not be extended by source-level classes
3741 if (st.tsym != null &&
3742 ((st.tsym.flags_field & Flags.ENUM) != 0) &&
3743 ((c.flags_field & (Flags.ENUM | Flags.COMPOUND)) == 0) &&
3744 !target.compilerBootstrap(c)) {
3745 log.error(env.tree.pos(), "enum.types.not.extensible");
3746 }
3747 attribClassBody(env, c);
3749 chk.checkDeprecatedAnnotation(env.tree.pos(), c);
3750 } finally {
3751 env.info.returnResult = prevReturnRes;
3752 log.useSource(prev);
3753 chk.setLint(prevLint);
3754 }
3756 }
3757 }
3759 public void visitImport(JCImport tree) {
3760 // nothing to do
3761 }
3763 /** Finish the attribution of a class. */
3764 private void attribClassBody(Env<AttrContext> env, ClassSymbol c) {
3765 JCClassDecl tree = (JCClassDecl)env.tree;
3766 Assert.check(c == tree.sym);
3768 // Validate annotations
3769 chk.validateAnnotations(tree.mods.annotations, c);
3771 // Validate type parameters, supertype and interfaces.
3772 attribBounds(tree.typarams);
3773 if (!c.isAnonymous()) {
3774 //already checked if anonymous
3775 chk.validate(tree.typarams, env);
3776 chk.validate(tree.extending, env);
3777 chk.validate(tree.implementing, env);
3778 }
3780 // If this is a non-abstract class, check that it has no abstract
3781 // methods or unimplemented methods of an implemented interface.
3782 if ((c.flags() & (ABSTRACT | INTERFACE)) == 0) {
3783 if (!relax)
3784 chk.checkAllDefined(tree.pos(), c);
3785 }
3787 if ((c.flags() & ANNOTATION) != 0) {
3788 if (tree.implementing.nonEmpty())
3789 log.error(tree.implementing.head.pos(),
3790 "cant.extend.intf.annotation");
3791 if (tree.typarams.nonEmpty())
3792 log.error(tree.typarams.head.pos(),
3793 "intf.annotation.cant.have.type.params");
3795 // If this annotation has a @ContainedBy, validate
3796 Attribute.Compound containedBy = c.attribute(syms.containedByType.tsym);
3797 if (containedBy != null) {
3798 // get diagnositc position for error reporting
3799 DiagnosticPosition cbPos = getDiagnosticPosition(tree, containedBy.type);
3800 Assert.checkNonNull(cbPos);
3802 chk.validateContainedBy(c, containedBy, cbPos);
3803 }
3805 // If this annotation has a @ContainerFor, validate
3806 Attribute.Compound containerFor = c.attribute(syms.containerForType.tsym);
3807 if (containerFor != null) {
3808 // get diagnositc position for error reporting
3809 DiagnosticPosition cfPos = getDiagnosticPosition(tree, containerFor.type);
3810 Assert.checkNonNull(cfPos);
3812 chk.validateContainerFor(c, containerFor, cfPos);
3813 }
3814 } else {
3815 // Check that all extended classes and interfaces
3816 // are compatible (i.e. no two define methods with same arguments
3817 // yet different return types). (JLS 8.4.6.3)
3818 chk.checkCompatibleSupertypes(tree.pos(), c.type);
3819 if (allowDefaultMethods) {
3820 chk.checkDefaultMethodClashes(tree.pos(), c.type);
3821 }
3822 }
3824 // Check that class does not import the same parameterized interface
3825 // with two different argument lists.
3826 chk.checkClassBounds(tree.pos(), c.type);
3828 tree.type = c.type;
3830 for (List<JCTypeParameter> l = tree.typarams;
3831 l.nonEmpty(); l = l.tail) {
3832 Assert.checkNonNull(env.info.scope.lookup(l.head.name).scope);
3833 }
3835 // Check that a generic class doesn't extend Throwable
3836 if (!c.type.allparams().isEmpty() && types.isSubtype(c.type, syms.throwableType))
3837 log.error(tree.extending.pos(), "generic.throwable");
3839 // Check that all methods which implement some
3840 // method conform to the method they implement.
3841 chk.checkImplementations(tree);
3843 //check that a resource implementing AutoCloseable cannot throw InterruptedException
3844 checkAutoCloseable(tree.pos(), env, c.type);
3846 for (List<JCTree> l = tree.defs; l.nonEmpty(); l = l.tail) {
3847 // Attribute declaration
3848 attribStat(l.head, env);
3849 // Check that declarations in inner classes are not static (JLS 8.1.2)
3850 // Make an exception for static constants.
3851 if (c.owner.kind != PCK &&
3852 ((c.flags() & STATIC) == 0 || c.name == names.empty) &&
3853 (TreeInfo.flags(l.head) & (STATIC | INTERFACE)) != 0) {
3854 Symbol sym = null;
3855 if (l.head.hasTag(VARDEF)) sym = ((JCVariableDecl) l.head).sym;
3856 if (sym == null ||
3857 sym.kind != VAR ||
3858 ((VarSymbol) sym).getConstValue() == null)
3859 log.error(l.head.pos(), "icls.cant.have.static.decl", c);
3860 }
3861 }
3863 // Check for cycles among non-initial constructors.
3864 chk.checkCyclicConstructors(tree);
3866 // Check for cycles among annotation elements.
3867 chk.checkNonCyclicElements(tree);
3869 // Check for proper use of serialVersionUID
3870 if (env.info.lint.isEnabled(LintCategory.SERIAL) &&
3871 isSerializable(c) &&
3872 (c.flags() & Flags.ENUM) == 0 &&
3873 (c.flags() & ABSTRACT) == 0) {
3874 checkSerialVersionUID(tree, c);
3875 }
3876 }
3877 // where
3878 /** get a diagnostic position for an attribute of Type t, or null if attribute missing */
3879 private DiagnosticPosition getDiagnosticPosition(JCClassDecl tree, Type t) {
3880 for(List<JCAnnotation> al = tree.mods.annotations; !al.isEmpty(); al = al.tail) {
3881 if (types.isSameType(al.head.annotationType.type, t))
3882 return al.head.pos();
3883 }
3885 return null;
3886 }
3888 /** check if a class is a subtype of Serializable, if that is available. */
3889 private boolean isSerializable(ClassSymbol c) {
3890 try {
3891 syms.serializableType.complete();
3892 }
3893 catch (CompletionFailure e) {
3894 return false;
3895 }
3896 return types.isSubtype(c.type, syms.serializableType);
3897 }
3899 /** Check that an appropriate serialVersionUID member is defined. */
3900 private void checkSerialVersionUID(JCClassDecl tree, ClassSymbol c) {
3902 // check for presence of serialVersionUID
3903 Scope.Entry e = c.members().lookup(names.serialVersionUID);
3904 while (e.scope != null && e.sym.kind != VAR) e = e.next();
3905 if (e.scope == null) {
3906 log.warning(LintCategory.SERIAL,
3907 tree.pos(), "missing.SVUID", c);
3908 return;
3909 }
3911 // check that it is static final
3912 VarSymbol svuid = (VarSymbol)e.sym;
3913 if ((svuid.flags() & (STATIC | FINAL)) !=
3914 (STATIC | FINAL))
3915 log.warning(LintCategory.SERIAL,
3916 TreeInfo.diagnosticPositionFor(svuid, tree), "improper.SVUID", c);
3918 // check that it is long
3919 else if (!svuid.type.hasTag(LONG))
3920 log.warning(LintCategory.SERIAL,
3921 TreeInfo.diagnosticPositionFor(svuid, tree), "long.SVUID", c);
3923 // check constant
3924 else if (svuid.getConstValue() == null)
3925 log.warning(LintCategory.SERIAL,
3926 TreeInfo.diagnosticPositionFor(svuid, tree), "constant.SVUID", c);
3927 }
3929 private Type capture(Type type) {
3930 return types.capture(type);
3931 }
3933 // <editor-fold desc="post-attribution visitor">
3935 /**
3936 * Handle missing types/symbols in an AST. This routine is useful when
3937 * the compiler has encountered some errors (which might have ended up
3938 * terminating attribution abruptly); if the compiler is used in fail-over
3939 * mode (e.g. by an IDE) and the AST contains semantic errors, this routine
3940 * prevents NPE to be progagated during subsequent compilation steps.
3941 */
3942 public void postAttr(JCTree tree) {
3943 new PostAttrAnalyzer().scan(tree);
3944 }
3946 class PostAttrAnalyzer extends TreeScanner {
3948 private void initTypeIfNeeded(JCTree that) {
3949 if (that.type == null) {
3950 that.type = syms.unknownType;
3951 }
3952 }
3954 @Override
3955 public void scan(JCTree tree) {
3956 if (tree == null) return;
3957 if (tree instanceof JCExpression) {
3958 initTypeIfNeeded(tree);
3959 }
3960 super.scan(tree);
3961 }
3963 @Override
3964 public void visitIdent(JCIdent that) {
3965 if (that.sym == null) {
3966 that.sym = syms.unknownSymbol;
3967 }
3968 }
3970 @Override
3971 public void visitSelect(JCFieldAccess that) {
3972 if (that.sym == null) {
3973 that.sym = syms.unknownSymbol;
3974 }
3975 super.visitSelect(that);
3976 }
3978 @Override
3979 public void visitClassDef(JCClassDecl that) {
3980 initTypeIfNeeded(that);
3981 if (that.sym == null) {
3982 that.sym = new ClassSymbol(0, that.name, that.type, syms.noSymbol);
3983 }
3984 super.visitClassDef(that);
3985 }
3987 @Override
3988 public void visitMethodDef(JCMethodDecl that) {
3989 initTypeIfNeeded(that);
3990 if (that.sym == null) {
3991 that.sym = new MethodSymbol(0, that.name, that.type, syms.noSymbol);
3992 }
3993 super.visitMethodDef(that);
3994 }
3996 @Override
3997 public void visitVarDef(JCVariableDecl that) {
3998 initTypeIfNeeded(that);
3999 if (that.sym == null) {
4000 that.sym = new VarSymbol(0, that.name, that.type, syms.noSymbol);
4001 that.sym.adr = 0;
4002 }
4003 super.visitVarDef(that);
4004 }
4006 @Override
4007 public void visitNewClass(JCNewClass that) {
4008 if (that.constructor == null) {
4009 that.constructor = new MethodSymbol(0, names.init, syms.unknownType, syms.noSymbol);
4010 }
4011 if (that.constructorType == null) {
4012 that.constructorType = syms.unknownType;
4013 }
4014 super.visitNewClass(that);
4015 }
4017 @Override
4018 public void visitAssignop(JCAssignOp that) {
4019 if (that.operator == null)
4020 that.operator = new OperatorSymbol(names.empty, syms.unknownType, -1, syms.noSymbol);
4021 super.visitAssignop(that);
4022 }
4024 @Override
4025 public void visitBinary(JCBinary that) {
4026 if (that.operator == null)
4027 that.operator = new OperatorSymbol(names.empty, syms.unknownType, -1, syms.noSymbol);
4028 super.visitBinary(that);
4029 }
4031 @Override
4032 public void visitUnary(JCUnary that) {
4033 if (that.operator == null)
4034 that.operator = new OperatorSymbol(names.empty, syms.unknownType, -1, syms.noSymbol);
4035 super.visitUnary(that);
4036 }
4038 @Override
4039 public void visitReference(JCMemberReference that) {
4040 super.visitReference(that);
4041 if (that.sym == null) {
4042 that.sym = new MethodSymbol(0, names.empty, syms.unknownType, syms.noSymbol);
4043 }
4044 }
4045 }
4046 // </editor-fold>
4047 }
