Mon, 12 Aug 2013 17:28:31 +0100
8021567: Javac doesn't report \"java: reference to method is ambiguous\" any more
Summary: Javac incorrectly forgets about constant folding results within lambdas
Reviewed-by: jjg, vromero
1 /*
2 * Copyright (c) 1999, 2013, Oracle and/or its affiliates. All rights reserved.
3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
4 *
5 * This code is free software; you can redistribute it and/or modify it
6 * under the terms of the GNU General Public License version 2 only, as
7 * published by the Free Software Foundation. Oracle designates this
8 * particular file as subject to the "Classpath" exception as provided
9 * by Oracle in the LICENSE file that accompanied this code.
10 *
11 * This code is distributed in the hope that it will be useful, but WITHOUT
12 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
13 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
14 * version 2 for more details (a copy is included in the LICENSE file that
15 * accompanied this code).
16 *
17 * You should have received a copy of the GNU General Public License version
18 * 2 along with this work; if not, write to the Free Software Foundation,
19 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
20 *
21 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
22 * or visit www.oracle.com if you need additional information or have any
23 * questions.
24 */
26 package com.sun.tools.javac.comp;
28 import java.util.*;
30 import javax.lang.model.element.ElementKind;
31 import javax.lang.model.type.TypeKind;
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.FreeTypeListener;
47 import com.sun.tools.javac.jvm.*;
48 import com.sun.tools.javac.tree.*;
49 import com.sun.tools.javac.tree.JCTree.*;
50 import com.sun.tools.javac.tree.JCTree.JCPolyExpression.*;
51 import com.sun.tools.javac.util.*;
52 import com.sun.tools.javac.util.JCDiagnostic.DiagnosticPosition;
53 import com.sun.tools.javac.util.List;
54 import static com.sun.tools.javac.code.Flags.*;
55 import static com.sun.tools.javac.code.Flags.ANNOTATION;
56 import static com.sun.tools.javac.code.Flags.BLOCK;
57 import static com.sun.tools.javac.code.Kinds.*;
58 import static com.sun.tools.javac.code.Kinds.ERRONEOUS;
59 import static com.sun.tools.javac.code.TypeTag.*;
60 import static com.sun.tools.javac.code.TypeTag.WILDCARD;
61 import static com.sun.tools.javac.tree.JCTree.Tag.*;
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 allowTypeAnnos = source.allowTypeAnnotations();
138 allowLambda = source.allowLambda();
139 allowDefaultMethods = source.allowDefaultMethods();
140 sourceName = source.name;
141 relax = (options.isSet("-retrofit") ||
142 options.isSet("-relax"));
143 findDiamonds = options.get("findDiamond") != null &&
144 source.allowDiamond();
145 useBeforeDeclarationWarning = options.isSet("useBeforeDeclarationWarning");
146 identifyLambdaCandidate = options.getBoolean("identifyLambdaCandidate", false);
148 statInfo = new ResultInfo(NIL, Type.noType);
149 varInfo = new ResultInfo(VAR, Type.noType);
150 unknownExprInfo = new ResultInfo(VAL, Type.noType);
151 unknownAnyPolyInfo = new ResultInfo(VAL, Infer.anyPoly);
152 unknownTypeInfo = new ResultInfo(TYP, Type.noType);
153 unknownTypeExprInfo = new ResultInfo(Kinds.TYP | Kinds.VAL, Type.noType);
154 recoveryInfo = new RecoveryInfo(deferredAttr.emptyDeferredAttrContext);
155 }
157 /** Switch: relax some constraints for retrofit mode.
158 */
159 boolean relax;
161 /** Switch: support target-typing inference
162 */
163 boolean allowPoly;
165 /** Switch: support type annotations.
166 */
167 boolean allowTypeAnnos;
169 /** Switch: support generics?
170 */
171 boolean allowGenerics;
173 /** Switch: allow variable-arity methods.
174 */
175 boolean allowVarargs;
177 /** Switch: support enums?
178 */
179 boolean allowEnums;
181 /** Switch: support boxing and unboxing?
182 */
183 boolean allowBoxing;
185 /** Switch: support covariant result types?
186 */
187 boolean allowCovariantReturns;
189 /** Switch: support lambda expressions ?
190 */
191 boolean allowLambda;
193 /** Switch: support default methods ?
194 */
195 boolean allowDefaultMethods;
197 /** Switch: allow references to surrounding object from anonymous
198 * objects during constructor call?
199 */
200 boolean allowAnonOuterThis;
202 /** Switch: generates a warning if diamond can be safely applied
203 * to a given new expression
204 */
205 boolean findDiamonds;
207 /**
208 * Internally enables/disables diamond finder feature
209 */
210 static final boolean allowDiamondFinder = true;
212 /**
213 * Switch: warn about use of variable before declaration?
214 * RFE: 6425594
215 */
216 boolean useBeforeDeclarationWarning;
218 /**
219 * Switch: generate warnings whenever an anonymous inner class that is convertible
220 * to a lambda expression is found
221 */
222 boolean identifyLambdaCandidate;
224 /**
225 * Switch: allow strings in switch?
226 */
227 boolean allowStringsInSwitch;
229 /**
230 * Switch: name of source level; used for error reporting.
231 */
232 String sourceName;
234 /** Check kind and type of given tree against protokind and prototype.
235 * If check succeeds, store type in tree and return it.
236 * If check fails, store errType in tree and return it.
237 * No checks are performed if the prototype is a method type.
238 * It is not necessary in this case since we know that kind and type
239 * are correct.
240 *
241 * @param tree The tree whose kind and type is checked
242 * @param ownkind The computed kind of the tree
243 * @param resultInfo The expected result of the tree
244 */
245 Type check(final JCTree tree, final Type found, final int ownkind, final ResultInfo resultInfo) {
246 InferenceContext inferenceContext = resultInfo.checkContext.inferenceContext();
247 Type owntype = found;
248 if (!owntype.hasTag(ERROR) && !resultInfo.pt.hasTag(METHOD) && !resultInfo.pt.hasTag(FORALL)) {
249 if (allowPoly && inferenceContext.free(found)) {
250 inferenceContext.addFreeTypeListener(List.of(found, resultInfo.pt), new FreeTypeListener() {
251 @Override
252 public void typesInferred(InferenceContext inferenceContext) {
253 ResultInfo pendingResult =
254 resultInfo.dup(inferenceContext.asInstType(resultInfo.pt));
255 check(tree, inferenceContext.asInstType(found), ownkind, pendingResult);
256 }
257 });
258 return tree.type = resultInfo.pt;
259 } else {
260 if ((ownkind & ~resultInfo.pkind) == 0) {
261 owntype = resultInfo.check(tree, owntype);
262 } else {
263 log.error(tree.pos(), "unexpected.type",
264 kindNames(resultInfo.pkind),
265 kindName(ownkind));
266 owntype = types.createErrorType(owntype);
267 }
268 }
269 }
270 tree.type = owntype;
271 return owntype;
272 }
274 /** Is given blank final variable assignable, i.e. in a scope where it
275 * may be assigned to even though it is final?
276 * @param v The blank final variable.
277 * @param env The current environment.
278 */
279 boolean isAssignableAsBlankFinal(VarSymbol v, Env<AttrContext> env) {
280 Symbol owner = owner(env);
281 // owner refers to the innermost variable, method or
282 // initializer block declaration at this point.
283 return
284 v.owner == owner
285 ||
286 ((owner.name == names.init || // i.e. we are in a constructor
287 owner.kind == VAR || // i.e. we are in a variable initializer
288 (owner.flags() & BLOCK) != 0) // i.e. we are in an initializer block
289 &&
290 v.owner == owner.owner
291 &&
292 ((v.flags() & STATIC) != 0) == Resolve.isStatic(env));
293 }
295 /**
296 * Return the innermost enclosing owner symbol in a given attribution context
297 */
298 Symbol owner(Env<AttrContext> env) {
299 while (true) {
300 switch (env.tree.getTag()) {
301 case VARDEF:
302 //a field can be owner
303 VarSymbol vsym = ((JCVariableDecl)env.tree).sym;
304 if (vsym.owner.kind == TYP) {
305 return vsym;
306 }
307 break;
308 case METHODDEF:
309 //method def is always an owner
310 return ((JCMethodDecl)env.tree).sym;
311 case CLASSDEF:
312 //class def is always an owner
313 return ((JCClassDecl)env.tree).sym;
314 case LAMBDA:
315 //a lambda is an owner - return a fresh synthetic method symbol
316 return new MethodSymbol(0, names.empty, null, syms.methodClass);
317 case BLOCK:
318 //static/instance init blocks are owner
319 Symbol blockSym = env.info.scope.owner;
320 if ((blockSym.flags() & BLOCK) != 0) {
321 return blockSym;
322 }
323 break;
324 case TOPLEVEL:
325 //toplevel is always an owner (for pkge decls)
326 return env.info.scope.owner;
327 }
328 Assert.checkNonNull(env.next);
329 env = env.next;
330 }
331 }
333 /** Check that variable can be assigned to.
334 * @param pos The current source code position.
335 * @param v The assigned varaible
336 * @param base If the variable is referred to in a Select, the part
337 * to the left of the `.', null otherwise.
338 * @param env The current environment.
339 */
340 void checkAssignable(DiagnosticPosition pos, VarSymbol v, JCTree base, Env<AttrContext> env) {
341 if ((v.flags() & FINAL) != 0 &&
342 ((v.flags() & HASINIT) != 0
343 ||
344 !((base == null ||
345 (base.hasTag(IDENT) && TreeInfo.name(base) == names._this)) &&
346 isAssignableAsBlankFinal(v, env)))) {
347 if (v.isResourceVariable()) { //TWR resource
348 log.error(pos, "try.resource.may.not.be.assigned", v);
349 } else {
350 log.error(pos, "cant.assign.val.to.final.var", v);
351 }
352 }
353 }
355 /** Does tree represent a static reference to an identifier?
356 * It is assumed that tree is either a SELECT or an IDENT.
357 * We have to weed out selects from non-type names here.
358 * @param tree The candidate tree.
359 */
360 boolean isStaticReference(JCTree tree) {
361 if (tree.hasTag(SELECT)) {
362 Symbol lsym = TreeInfo.symbol(((JCFieldAccess) tree).selected);
363 if (lsym == null || lsym.kind != TYP) {
364 return false;
365 }
366 }
367 return true;
368 }
370 /** Is this symbol a type?
371 */
372 static boolean isType(Symbol sym) {
373 return sym != null && sym.kind == TYP;
374 }
376 /** The current `this' symbol.
377 * @param env The current environment.
378 */
379 Symbol thisSym(DiagnosticPosition pos, Env<AttrContext> env) {
380 return rs.resolveSelf(pos, env, env.enclClass.sym, names._this);
381 }
383 /** Attribute a parsed identifier.
384 * @param tree Parsed identifier name
385 * @param topLevel The toplevel to use
386 */
387 public Symbol attribIdent(JCTree tree, JCCompilationUnit topLevel) {
388 Env<AttrContext> localEnv = enter.topLevelEnv(topLevel);
389 localEnv.enclClass = make.ClassDef(make.Modifiers(0),
390 syms.errSymbol.name,
391 null, null, null, null);
392 localEnv.enclClass.sym = syms.errSymbol;
393 return tree.accept(identAttributer, localEnv);
394 }
395 // where
396 private TreeVisitor<Symbol,Env<AttrContext>> identAttributer = new IdentAttributer();
397 private class IdentAttributer extends SimpleTreeVisitor<Symbol,Env<AttrContext>> {
398 @Override
399 public Symbol visitMemberSelect(MemberSelectTree node, Env<AttrContext> env) {
400 Symbol site = visit(node.getExpression(), env);
401 if (site.kind == ERR)
402 return site;
403 Name name = (Name)node.getIdentifier();
404 if (site.kind == PCK) {
405 env.toplevel.packge = (PackageSymbol)site;
406 return rs.findIdentInPackage(env, (TypeSymbol)site, name, TYP | PCK);
407 } else {
408 env.enclClass.sym = (ClassSymbol)site;
409 return rs.findMemberType(env, site.asType(), name, (TypeSymbol)site);
410 }
411 }
413 @Override
414 public Symbol visitIdentifier(IdentifierTree node, Env<AttrContext> env) {
415 return rs.findIdent(env, (Name)node.getName(), TYP | PCK);
416 }
417 }
419 public Type coerce(Type etype, Type ttype) {
420 return cfolder.coerce(etype, ttype);
421 }
423 public Type attribType(JCTree node, TypeSymbol sym) {
424 Env<AttrContext> env = enter.typeEnvs.get(sym);
425 Env<AttrContext> localEnv = env.dup(node, env.info.dup());
426 return attribTree(node, localEnv, unknownTypeInfo);
427 }
429 public Type attribImportQualifier(JCImport tree, Env<AttrContext> env) {
430 // Attribute qualifying package or class.
431 JCFieldAccess s = (JCFieldAccess)tree.qualid;
432 return attribTree(s.selected,
433 env,
434 new ResultInfo(tree.staticImport ? TYP : (TYP | PCK),
435 Type.noType));
436 }
438 public Env<AttrContext> attribExprToTree(JCTree expr, Env<AttrContext> env, JCTree tree) {
439 breakTree = tree;
440 JavaFileObject prev = log.useSource(env.toplevel.sourcefile);
441 try {
442 attribExpr(expr, env);
443 } catch (BreakAttr b) {
444 return b.env;
445 } catch (AssertionError ae) {
446 if (ae.getCause() instanceof BreakAttr) {
447 return ((BreakAttr)(ae.getCause())).env;
448 } else {
449 throw ae;
450 }
451 } finally {
452 breakTree = null;
453 log.useSource(prev);
454 }
455 return env;
456 }
458 public Env<AttrContext> attribStatToTree(JCTree stmt, Env<AttrContext> env, JCTree tree) {
459 breakTree = tree;
460 JavaFileObject prev = log.useSource(env.toplevel.sourcefile);
461 try {
462 attribStat(stmt, env);
463 } catch (BreakAttr b) {
464 return b.env;
465 } catch (AssertionError ae) {
466 if (ae.getCause() instanceof BreakAttr) {
467 return ((BreakAttr)(ae.getCause())).env;
468 } else {
469 throw ae;
470 }
471 } finally {
472 breakTree = null;
473 log.useSource(prev);
474 }
475 return env;
476 }
478 private JCTree breakTree = null;
480 private static class BreakAttr extends RuntimeException {
481 static final long serialVersionUID = -6924771130405446405L;
482 private Env<AttrContext> env;
483 private BreakAttr(Env<AttrContext> env) {
484 this.env = env;
485 }
486 }
488 class ResultInfo {
489 final int pkind;
490 final Type pt;
491 final CheckContext checkContext;
493 ResultInfo(int pkind, Type pt) {
494 this(pkind, pt, chk.basicHandler);
495 }
497 protected ResultInfo(int pkind, Type pt, CheckContext checkContext) {
498 this.pkind = pkind;
499 this.pt = pt;
500 this.checkContext = checkContext;
501 }
503 protected Type check(final DiagnosticPosition pos, final Type found) {
504 return chk.checkType(pos, found, pt, checkContext);
505 }
507 protected ResultInfo dup(Type newPt) {
508 return new ResultInfo(pkind, newPt, checkContext);
509 }
511 protected ResultInfo dup(CheckContext newContext) {
512 return new ResultInfo(pkind, pt, newContext);
513 }
514 }
516 class RecoveryInfo extends ResultInfo {
518 public RecoveryInfo(final DeferredAttr.DeferredAttrContext deferredAttrContext) {
519 super(Kinds.VAL, Type.recoveryType, new Check.NestedCheckContext(chk.basicHandler) {
520 @Override
521 public DeferredAttr.DeferredAttrContext deferredAttrContext() {
522 return deferredAttrContext;
523 }
524 @Override
525 public boolean compatible(Type found, Type req, Warner warn) {
526 return true;
527 }
528 @Override
529 public void report(DiagnosticPosition pos, JCDiagnostic details) {
530 chk.basicHandler.report(pos, details);
531 }
532 });
533 }
534 }
536 final ResultInfo statInfo;
537 final ResultInfo varInfo;
538 final ResultInfo unknownAnyPolyInfo;
539 final ResultInfo unknownExprInfo;
540 final ResultInfo unknownTypeInfo;
541 final ResultInfo unknownTypeExprInfo;
542 final ResultInfo recoveryInfo;
544 Type pt() {
545 return resultInfo.pt;
546 }
548 int pkind() {
549 return resultInfo.pkind;
550 }
552 /* ************************************************************************
553 * Visitor methods
554 *************************************************************************/
556 /** Visitor argument: the current environment.
557 */
558 Env<AttrContext> env;
560 /** Visitor argument: the currently expected attribution result.
561 */
562 ResultInfo resultInfo;
564 /** Visitor result: the computed type.
565 */
566 Type result;
568 /** Visitor method: attribute a tree, catching any completion failure
569 * exceptions. Return the tree's type.
570 *
571 * @param tree The tree to be visited.
572 * @param env The environment visitor argument.
573 * @param resultInfo The result info visitor argument.
574 */
575 Type attribTree(JCTree tree, Env<AttrContext> env, ResultInfo resultInfo) {
576 Env<AttrContext> prevEnv = this.env;
577 ResultInfo prevResult = this.resultInfo;
578 try {
579 this.env = env;
580 this.resultInfo = resultInfo;
581 tree.accept(this);
582 if (tree == breakTree &&
583 resultInfo.checkContext.deferredAttrContext().mode == AttrMode.CHECK) {
584 throw new BreakAttr(copyEnv(env));
585 }
586 return result;
587 } catch (CompletionFailure ex) {
588 tree.type = syms.errType;
589 return chk.completionError(tree.pos(), ex);
590 } finally {
591 this.env = prevEnv;
592 this.resultInfo = prevResult;
593 }
594 }
596 Env<AttrContext> copyEnv(Env<AttrContext> env) {
597 Env<AttrContext> newEnv =
598 env.dup(env.tree, env.info.dup(copyScope(env.info.scope)));
599 if (newEnv.outer != null) {
600 newEnv.outer = copyEnv(newEnv.outer);
601 }
602 return newEnv;
603 }
605 Scope copyScope(Scope sc) {
606 Scope newScope = new Scope(sc.owner);
607 List<Symbol> elemsList = List.nil();
608 while (sc != null) {
609 for (Scope.Entry e = sc.elems ; e != null ; e = e.sibling) {
610 elemsList = elemsList.prepend(e.sym);
611 }
612 sc = sc.next;
613 }
614 for (Symbol s : elemsList) {
615 newScope.enter(s);
616 }
617 return newScope;
618 }
620 /** Derived visitor method: attribute an expression tree.
621 */
622 public Type attribExpr(JCTree tree, Env<AttrContext> env, Type pt) {
623 return attribTree(tree, env, new ResultInfo(VAL, !pt.hasTag(ERROR) ? pt : Type.noType));
624 }
626 /** Derived visitor method: attribute an expression tree with
627 * no constraints on the computed type.
628 */
629 public Type attribExpr(JCTree tree, Env<AttrContext> env) {
630 return attribTree(tree, env, unknownExprInfo);
631 }
633 /** Derived visitor method: attribute a type tree.
634 */
635 public Type attribType(JCTree tree, Env<AttrContext> env) {
636 Type result = attribType(tree, env, Type.noType);
637 return result;
638 }
640 /** Derived visitor method: attribute a type tree.
641 */
642 Type attribType(JCTree tree, Env<AttrContext> env, Type pt) {
643 Type result = attribTree(tree, env, new ResultInfo(TYP, pt));
644 return result;
645 }
647 /** Derived visitor method: attribute a statement or definition tree.
648 */
649 public Type attribStat(JCTree tree, Env<AttrContext> env) {
650 return attribTree(tree, env, statInfo);
651 }
653 /** Attribute a list of expressions, returning a list of types.
654 */
655 List<Type> attribExprs(List<JCExpression> trees, Env<AttrContext> env, Type pt) {
656 ListBuffer<Type> ts = new ListBuffer<Type>();
657 for (List<JCExpression> l = trees; l.nonEmpty(); l = l.tail)
658 ts.append(attribExpr(l.head, env, pt));
659 return ts.toList();
660 }
662 /** Attribute a list of statements, returning nothing.
663 */
664 <T extends JCTree> void attribStats(List<T> trees, Env<AttrContext> env) {
665 for (List<T> l = trees; l.nonEmpty(); l = l.tail)
666 attribStat(l.head, env);
667 }
669 /** Attribute the arguments in a method call, returning the method kind.
670 */
671 int attribArgs(List<JCExpression> trees, Env<AttrContext> env, ListBuffer<Type> argtypes) {
672 int kind = VAL;
673 for (JCExpression arg : trees) {
674 Type argtype;
675 if (allowPoly && deferredAttr.isDeferred(env, arg)) {
676 argtype = deferredAttr.new DeferredType(arg, env);
677 kind |= POLY;
678 } else {
679 argtype = chk.checkNonVoid(arg, attribTree(arg, env, unknownAnyPolyInfo));
680 }
681 argtypes.append(argtype);
682 }
683 return kind;
684 }
686 /** Attribute a type argument list, returning a list of types.
687 * Caller is responsible for calling checkRefTypes.
688 */
689 List<Type> attribAnyTypes(List<JCExpression> trees, Env<AttrContext> env) {
690 ListBuffer<Type> argtypes = new ListBuffer<Type>();
691 for (List<JCExpression> l = trees; l.nonEmpty(); l = l.tail)
692 argtypes.append(attribType(l.head, env));
693 return argtypes.toList();
694 }
696 /** Attribute a type argument list, returning a list of types.
697 * Check that all the types are references.
698 */
699 List<Type> attribTypes(List<JCExpression> trees, Env<AttrContext> env) {
700 List<Type> types = attribAnyTypes(trees, env);
701 return chk.checkRefTypes(trees, types);
702 }
704 /**
705 * Attribute type variables (of generic classes or methods).
706 * Compound types are attributed later in attribBounds.
707 * @param typarams the type variables to enter
708 * @param env the current environment
709 */
710 void attribTypeVariables(List<JCTypeParameter> typarams, Env<AttrContext> env) {
711 for (JCTypeParameter tvar : typarams) {
712 TypeVar a = (TypeVar)tvar.type;
713 a.tsym.flags_field |= UNATTRIBUTED;
714 a.bound = Type.noType;
715 if (!tvar.bounds.isEmpty()) {
716 List<Type> bounds = List.of(attribType(tvar.bounds.head, env));
717 for (JCExpression bound : tvar.bounds.tail)
718 bounds = bounds.prepend(attribType(bound, env));
719 types.setBounds(a, bounds.reverse());
720 } else {
721 // if no bounds are given, assume a single bound of
722 // java.lang.Object.
723 types.setBounds(a, List.of(syms.objectType));
724 }
725 a.tsym.flags_field &= ~UNATTRIBUTED;
726 }
727 for (JCTypeParameter tvar : typarams) {
728 chk.checkNonCyclic(tvar.pos(), (TypeVar)tvar.type);
729 }
730 }
732 /**
733 * Attribute the type references in a list of annotations.
734 */
735 void attribAnnotationTypes(List<JCAnnotation> annotations,
736 Env<AttrContext> env) {
737 for (List<JCAnnotation> al = annotations; al.nonEmpty(); al = al.tail) {
738 JCAnnotation a = al.head;
739 attribType(a.annotationType, env);
740 }
741 }
743 /**
744 * Attribute a "lazy constant value".
745 * @param env The env for the const value
746 * @param initializer The initializer for the const value
747 * @param type The expected type, or null
748 * @see VarSymbol#setLazyConstValue
749 */
750 public Object attribLazyConstantValue(Env<AttrContext> env,
751 JCTree.JCExpression initializer,
752 Type type) {
754 /* When this env was created, it didn't have the correct lint nor had
755 * annotations has been processed.
756 * But now at this phase we have already processed annotations and the
757 * correct lint must have been set in chk, so we should use that one to
758 * attribute the initializer.
759 */
760 Lint prevLint = env.info.lint;
761 env.info.lint = chk.getLint();
763 JavaFileObject prevSource = log.useSource(env.toplevel.sourcefile);
765 try {
766 // Use null as symbol to not attach the type annotation to any symbol.
767 // The initializer will later also be visited and then we'll attach
768 // to the symbol.
769 // This prevents having multiple type annotations, just because of
770 // lazy constant value evaluation.
771 memberEnter.typeAnnotate(initializer, env, null);
772 annotate.flush();
773 Type itype = attribExpr(initializer, env, type);
774 if (itype.constValue() != null) {
775 return coerce(itype, type).constValue();
776 } else {
777 return null;
778 }
779 } finally {
780 env.info.lint = prevLint;
781 log.useSource(prevSource);
782 }
783 }
785 /** Attribute type reference in an `extends' or `implements' clause.
786 * Supertypes of anonymous inner classes are usually already attributed.
787 *
788 * @param tree The tree making up the type reference.
789 * @param env The environment current at the reference.
790 * @param classExpected true if only a class is expected here.
791 * @param interfaceExpected true if only an interface is expected here.
792 */
793 Type attribBase(JCTree tree,
794 Env<AttrContext> env,
795 boolean classExpected,
796 boolean interfaceExpected,
797 boolean checkExtensible) {
798 Type t = tree.type != null ?
799 tree.type :
800 attribType(tree, env);
801 return checkBase(t, tree, env, classExpected, interfaceExpected, checkExtensible);
802 }
803 Type checkBase(Type t,
804 JCTree tree,
805 Env<AttrContext> env,
806 boolean classExpected,
807 boolean interfaceExpected,
808 boolean checkExtensible) {
809 if (t.isErroneous())
810 return t;
811 if (t.hasTag(TYPEVAR) && !classExpected && !interfaceExpected) {
812 // check that type variable is already visible
813 if (t.getUpperBound() == null) {
814 log.error(tree.pos(), "illegal.forward.ref");
815 return types.createErrorType(t);
816 }
817 } else {
818 t = chk.checkClassType(tree.pos(), t, checkExtensible|!allowGenerics);
819 }
820 if (interfaceExpected && (t.tsym.flags() & INTERFACE) == 0) {
821 log.error(tree.pos(), "intf.expected.here");
822 // return errType is necessary since otherwise there might
823 // be undetected cycles which cause attribution to loop
824 return types.createErrorType(t);
825 } else if (checkExtensible &&
826 classExpected &&
827 (t.tsym.flags() & INTERFACE) != 0) {
828 log.error(tree.pos(), "no.intf.expected.here");
829 return types.createErrorType(t);
830 }
831 if (checkExtensible &&
832 ((t.tsym.flags() & FINAL) != 0)) {
833 log.error(tree.pos(),
834 "cant.inherit.from.final", t.tsym);
835 }
836 chk.checkNonCyclic(tree.pos(), t);
837 return t;
838 }
840 Type attribIdentAsEnumType(Env<AttrContext> env, JCIdent id) {
841 Assert.check((env.enclClass.sym.flags() & ENUM) != 0);
842 id.type = env.info.scope.owner.type;
843 id.sym = env.info.scope.owner;
844 return id.type;
845 }
847 public void visitClassDef(JCClassDecl tree) {
848 // Local classes have not been entered yet, so we need to do it now:
849 if ((env.info.scope.owner.kind & (VAR | MTH)) != 0)
850 enter.classEnter(tree, env);
852 ClassSymbol c = tree.sym;
853 if (c == null) {
854 // exit in case something drastic went wrong during enter.
855 result = null;
856 } else {
857 // make sure class has been completed:
858 c.complete();
860 // If this class appears as an anonymous class
861 // in a superclass constructor call where
862 // no explicit outer instance is given,
863 // disable implicit outer instance from being passed.
864 // (This would be an illegal access to "this before super").
865 if (env.info.isSelfCall &&
866 env.tree.hasTag(NEWCLASS) &&
867 ((JCNewClass) env.tree).encl == null)
868 {
869 c.flags_field |= NOOUTERTHIS;
870 }
871 attribClass(tree.pos(), c);
872 result = tree.type = c.type;
873 }
874 }
876 public void visitMethodDef(JCMethodDecl tree) {
877 MethodSymbol m = tree.sym;
878 boolean isDefaultMethod = (m.flags() & DEFAULT) != 0;
880 Lint lint = env.info.lint.augment(m);
881 Lint prevLint = chk.setLint(lint);
882 MethodSymbol prevMethod = chk.setMethod(m);
883 try {
884 deferredLintHandler.flush(tree.pos());
885 chk.checkDeprecatedAnnotation(tree.pos(), m);
888 // Create a new environment with local scope
889 // for attributing the method.
890 Env<AttrContext> localEnv = memberEnter.methodEnv(tree, env);
891 localEnv.info.lint = lint;
893 attribStats(tree.typarams, localEnv);
895 // If we override any other methods, check that we do so properly.
896 // JLS ???
897 if (m.isStatic()) {
898 chk.checkHideClashes(tree.pos(), env.enclClass.type, m);
899 } else {
900 chk.checkOverrideClashes(tree.pos(), env.enclClass.type, m);
901 }
902 chk.checkOverride(tree, m);
904 if (isDefaultMethod && types.overridesObjectMethod(m.enclClass(), m)) {
905 log.error(tree, "default.overrides.object.member", m.name, Kinds.kindName(m.location()), m.location());
906 }
908 // Enter all type parameters into the local method scope.
909 for (List<JCTypeParameter> l = tree.typarams; l.nonEmpty(); l = l.tail)
910 localEnv.info.scope.enterIfAbsent(l.head.type.tsym);
912 ClassSymbol owner = env.enclClass.sym;
913 if ((owner.flags() & ANNOTATION) != 0 &&
914 tree.params.nonEmpty())
915 log.error(tree.params.head.pos(),
916 "intf.annotation.members.cant.have.params");
918 // Attribute all value parameters.
919 for (List<JCVariableDecl> l = tree.params; l.nonEmpty(); l = l.tail) {
920 attribStat(l.head, localEnv);
921 }
923 chk.checkVarargsMethodDecl(localEnv, tree);
925 // Check that type parameters are well-formed.
926 chk.validate(tree.typarams, localEnv);
928 // Check that result type is well-formed.
929 chk.validate(tree.restype, localEnv);
931 // Check that receiver type is well-formed.
932 if (tree.recvparam != null) {
933 // Use a new environment to check the receiver parameter.
934 // Otherwise I get "might not have been initialized" errors.
935 // Is there a better way?
936 Env<AttrContext> newEnv = memberEnter.methodEnv(tree, env);
937 attribType(tree.recvparam, newEnv);
938 chk.validate(tree.recvparam, newEnv);
939 }
941 // annotation method checks
942 if ((owner.flags() & ANNOTATION) != 0) {
943 // annotation method cannot have throws clause
944 if (tree.thrown.nonEmpty()) {
945 log.error(tree.thrown.head.pos(),
946 "throws.not.allowed.in.intf.annotation");
947 }
948 // annotation method cannot declare type-parameters
949 if (tree.typarams.nonEmpty()) {
950 log.error(tree.typarams.head.pos(),
951 "intf.annotation.members.cant.have.type.params");
952 }
953 // validate annotation method's return type (could be an annotation type)
954 chk.validateAnnotationType(tree.restype);
955 // ensure that annotation method does not clash with members of Object/Annotation
956 chk.validateAnnotationMethod(tree.pos(), m);
958 if (tree.defaultValue != null) {
959 // if default value is an annotation, check it is a well-formed
960 // annotation value (e.g. no duplicate values, no missing values, etc.)
961 chk.validateAnnotationTree(tree.defaultValue);
962 }
963 }
965 for (List<JCExpression> l = tree.thrown; l.nonEmpty(); l = l.tail)
966 chk.checkType(l.head.pos(), l.head.type, syms.throwableType);
968 if (tree.body == null) {
969 // Empty bodies are only allowed for
970 // abstract, native, or interface methods, or for methods
971 // in a retrofit signature class.
972 if (isDefaultMethod || (tree.sym.flags() & (ABSTRACT | NATIVE)) == 0 &&
973 !relax)
974 log.error(tree.pos(), "missing.meth.body.or.decl.abstract");
975 if (tree.defaultValue != null) {
976 if ((owner.flags() & ANNOTATION) == 0)
977 log.error(tree.pos(),
978 "default.allowed.in.intf.annotation.member");
979 }
980 } else if ((tree.sym.flags() & ABSTRACT) != 0 && !isDefaultMethod) {
981 if ((owner.flags() & INTERFACE) != 0) {
982 log.error(tree.body.pos(), "intf.meth.cant.have.body");
983 } else {
984 log.error(tree.pos(), "abstract.meth.cant.have.body");
985 }
986 } else if ((tree.mods.flags & NATIVE) != 0) {
987 log.error(tree.pos(), "native.meth.cant.have.body");
988 } else {
989 // Add an implicit super() call unless an explicit call to
990 // super(...) or this(...) is given
991 // or we are compiling class java.lang.Object.
992 if (tree.name == names.init && owner.type != syms.objectType) {
993 JCBlock body = tree.body;
994 if (body.stats.isEmpty() ||
995 !TreeInfo.isSelfCall(body.stats.head)) {
996 body.stats = body.stats.
997 prepend(memberEnter.SuperCall(make.at(body.pos),
998 List.<Type>nil(),
999 List.<JCVariableDecl>nil(),
1000 false));
1001 } else if ((env.enclClass.sym.flags() & ENUM) != 0 &&
1002 (tree.mods.flags & GENERATEDCONSTR) == 0 &&
1003 TreeInfo.isSuperCall(body.stats.head)) {
1004 // enum constructors are not allowed to call super
1005 // directly, so make sure there aren't any super calls
1006 // in enum constructors, except in the compiler
1007 // generated one.
1008 log.error(tree.body.stats.head.pos(),
1009 "call.to.super.not.allowed.in.enum.ctor",
1010 env.enclClass.sym);
1011 }
1012 }
1014 // Attribute all type annotations in the body
1015 memberEnter.typeAnnotate(tree.body, localEnv, m);
1016 annotate.flush();
1018 // Attribute method body.
1019 attribStat(tree.body, localEnv);
1020 }
1022 localEnv.info.scope.leave();
1023 result = tree.type = m.type;
1024 chk.validateAnnotations(tree.mods.annotations, m);
1025 }
1026 finally {
1027 chk.setLint(prevLint);
1028 chk.setMethod(prevMethod);
1029 }
1030 }
1032 public void visitVarDef(JCVariableDecl tree) {
1033 // Local variables have not been entered yet, so we need to do it now:
1034 if (env.info.scope.owner.kind == MTH) {
1035 if (tree.sym != null) {
1036 // parameters have already been entered
1037 env.info.scope.enter(tree.sym);
1038 } else {
1039 memberEnter.memberEnter(tree, env);
1040 annotate.flush();
1041 }
1042 } else {
1043 if (tree.init != null) {
1044 // Field initializer expression need to be entered.
1045 memberEnter.typeAnnotate(tree.init, env, tree.sym);
1046 annotate.flush();
1047 }
1048 }
1050 VarSymbol v = tree.sym;
1051 Lint lint = env.info.lint.augment(v);
1052 Lint prevLint = chk.setLint(lint);
1054 // Check that the variable's declared type is well-formed.
1055 boolean isImplicitLambdaParameter = env.tree.hasTag(LAMBDA) &&
1056 ((JCLambda)env.tree).paramKind == JCLambda.ParameterKind.IMPLICIT &&
1057 (tree.sym.flags() & PARAMETER) != 0;
1058 chk.validate(tree.vartype, env, !isImplicitLambdaParameter);
1059 deferredLintHandler.flush(tree.pos());
1061 try {
1062 chk.checkDeprecatedAnnotation(tree.pos(), v);
1064 if (tree.init != null) {
1065 if ((v.flags_field & FINAL) != 0 &&
1066 !tree.init.hasTag(NEWCLASS) &&
1067 !tree.init.hasTag(LAMBDA) &&
1068 !tree.init.hasTag(REFERENCE)) {
1069 // In this case, `v' is final. Ensure that it's initializer is
1070 // evaluated.
1071 v.getConstValue(); // ensure initializer is evaluated
1072 } else {
1073 // Attribute initializer in a new environment
1074 // with the declared variable as owner.
1075 // Check that initializer conforms to variable's declared type.
1076 Env<AttrContext> initEnv = memberEnter.initEnv(tree, env);
1077 initEnv.info.lint = lint;
1078 // In order to catch self-references, we set the variable's
1079 // declaration position to maximal possible value, effectively
1080 // marking the variable as undefined.
1081 initEnv.info.enclVar = v;
1082 attribExpr(tree.init, initEnv, v.type);
1083 }
1084 }
1085 result = tree.type = v.type;
1086 chk.validateAnnotations(tree.mods.annotations, v);
1087 }
1088 finally {
1089 chk.setLint(prevLint);
1090 }
1091 }
1093 public void visitSkip(JCSkip tree) {
1094 result = null;
1095 }
1097 public void visitBlock(JCBlock tree) {
1098 if (env.info.scope.owner.kind == TYP) {
1099 // Block is a static or instance initializer;
1100 // let the owner of the environment be a freshly
1101 // created BLOCK-method.
1102 Env<AttrContext> localEnv =
1103 env.dup(tree, env.info.dup(env.info.scope.dupUnshared()));
1104 localEnv.info.scope.owner =
1105 new MethodSymbol(tree.flags | BLOCK |
1106 env.info.scope.owner.flags() & STRICTFP, names.empty, null,
1107 env.info.scope.owner);
1108 if ((tree.flags & STATIC) != 0) localEnv.info.staticLevel++;
1110 // Attribute all type annotations in the block
1111 memberEnter.typeAnnotate(tree, localEnv, localEnv.info.scope.owner);
1112 annotate.flush();
1114 {
1115 // Store init and clinit type annotations with the ClassSymbol
1116 // to allow output in Gen.normalizeDefs.
1117 ClassSymbol cs = (ClassSymbol)env.info.scope.owner;
1118 List<Attribute.TypeCompound> tas = localEnv.info.scope.owner.getRawTypeAttributes();
1119 if ((tree.flags & STATIC) != 0) {
1120 cs.appendClassInitTypeAttributes(tas);
1121 } else {
1122 cs.appendInitTypeAttributes(tas);
1123 }
1124 }
1126 attribStats(tree.stats, localEnv);
1127 } else {
1128 // Create a new local environment with a local scope.
1129 Env<AttrContext> localEnv =
1130 env.dup(tree, env.info.dup(env.info.scope.dup()));
1131 try {
1132 attribStats(tree.stats, localEnv);
1133 } finally {
1134 localEnv.info.scope.leave();
1135 }
1136 }
1137 result = null;
1138 }
1140 public void visitDoLoop(JCDoWhileLoop tree) {
1141 attribStat(tree.body, env.dup(tree));
1142 attribExpr(tree.cond, env, syms.booleanType);
1143 result = null;
1144 }
1146 public void visitWhileLoop(JCWhileLoop tree) {
1147 attribExpr(tree.cond, env, syms.booleanType);
1148 attribStat(tree.body, env.dup(tree));
1149 result = null;
1150 }
1152 public void visitForLoop(JCForLoop tree) {
1153 Env<AttrContext> loopEnv =
1154 env.dup(env.tree, env.info.dup(env.info.scope.dup()));
1155 try {
1156 attribStats(tree.init, loopEnv);
1157 if (tree.cond != null) attribExpr(tree.cond, loopEnv, syms.booleanType);
1158 loopEnv.tree = tree; // before, we were not in loop!
1159 attribStats(tree.step, loopEnv);
1160 attribStat(tree.body, loopEnv);
1161 result = null;
1162 }
1163 finally {
1164 loopEnv.info.scope.leave();
1165 }
1166 }
1168 public void visitForeachLoop(JCEnhancedForLoop tree) {
1169 Env<AttrContext> loopEnv =
1170 env.dup(env.tree, env.info.dup(env.info.scope.dup()));
1171 try {
1172 //the Formal Parameter of a for-each loop is not in the scope when
1173 //attributing the for-each expression; we mimick this by attributing
1174 //the for-each expression first (against original scope).
1175 Type exprType = types.upperBound(attribExpr(tree.expr, loopEnv));
1176 attribStat(tree.var, loopEnv);
1177 chk.checkNonVoid(tree.pos(), exprType);
1178 Type elemtype = types.elemtype(exprType); // perhaps expr is an array?
1179 if (elemtype == null) {
1180 // or perhaps expr implements Iterable<T>?
1181 Type base = types.asSuper(exprType, syms.iterableType.tsym);
1182 if (base == null) {
1183 log.error(tree.expr.pos(),
1184 "foreach.not.applicable.to.type",
1185 exprType,
1186 diags.fragment("type.req.array.or.iterable"));
1187 elemtype = types.createErrorType(exprType);
1188 } else {
1189 List<Type> iterableParams = base.allparams();
1190 elemtype = iterableParams.isEmpty()
1191 ? syms.objectType
1192 : types.upperBound(iterableParams.head);
1193 }
1194 }
1195 chk.checkType(tree.expr.pos(), elemtype, tree.var.sym.type);
1196 loopEnv.tree = tree; // before, we were not in loop!
1197 attribStat(tree.body, loopEnv);
1198 result = null;
1199 }
1200 finally {
1201 loopEnv.info.scope.leave();
1202 }
1203 }
1205 public void visitLabelled(JCLabeledStatement tree) {
1206 // Check that label is not used in an enclosing statement
1207 Env<AttrContext> env1 = env;
1208 while (env1 != null && !env1.tree.hasTag(CLASSDEF)) {
1209 if (env1.tree.hasTag(LABELLED) &&
1210 ((JCLabeledStatement) env1.tree).label == tree.label) {
1211 log.error(tree.pos(), "label.already.in.use",
1212 tree.label);
1213 break;
1214 }
1215 env1 = env1.next;
1216 }
1218 attribStat(tree.body, env.dup(tree));
1219 result = null;
1220 }
1222 public void visitSwitch(JCSwitch tree) {
1223 Type seltype = attribExpr(tree.selector, env);
1225 Env<AttrContext> switchEnv =
1226 env.dup(tree, env.info.dup(env.info.scope.dup()));
1228 try {
1230 boolean enumSwitch =
1231 allowEnums &&
1232 (seltype.tsym.flags() & Flags.ENUM) != 0;
1233 boolean stringSwitch = false;
1234 if (types.isSameType(seltype, syms.stringType)) {
1235 if (allowStringsInSwitch) {
1236 stringSwitch = true;
1237 } else {
1238 log.error(tree.selector.pos(), "string.switch.not.supported.in.source", sourceName);
1239 }
1240 }
1241 if (!enumSwitch && !stringSwitch)
1242 seltype = chk.checkType(tree.selector.pos(), seltype, syms.intType);
1244 // Attribute all cases and
1245 // check that there are no duplicate case labels or default clauses.
1246 Set<Object> labels = new HashSet<Object>(); // The set of case labels.
1247 boolean hasDefault = false; // Is there a default label?
1248 for (List<JCCase> l = tree.cases; l.nonEmpty(); l = l.tail) {
1249 JCCase c = l.head;
1250 Env<AttrContext> caseEnv =
1251 switchEnv.dup(c, env.info.dup(switchEnv.info.scope.dup()));
1252 try {
1253 if (c.pat != null) {
1254 if (enumSwitch) {
1255 Symbol sym = enumConstant(c.pat, seltype);
1256 if (sym == null) {
1257 log.error(c.pat.pos(), "enum.label.must.be.unqualified.enum");
1258 } else if (!labels.add(sym)) {
1259 log.error(c.pos(), "duplicate.case.label");
1260 }
1261 } else {
1262 Type pattype = attribExpr(c.pat, switchEnv, seltype);
1263 if (!pattype.hasTag(ERROR)) {
1264 if (pattype.constValue() == null) {
1265 log.error(c.pat.pos(),
1266 (stringSwitch ? "string.const.req" : "const.expr.req"));
1267 } else if (labels.contains(pattype.constValue())) {
1268 log.error(c.pos(), "duplicate.case.label");
1269 } else {
1270 labels.add(pattype.constValue());
1271 }
1272 }
1273 }
1274 } else if (hasDefault) {
1275 log.error(c.pos(), "duplicate.default.label");
1276 } else {
1277 hasDefault = true;
1278 }
1279 attribStats(c.stats, caseEnv);
1280 } finally {
1281 caseEnv.info.scope.leave();
1282 addVars(c.stats, switchEnv.info.scope);
1283 }
1284 }
1286 result = null;
1287 }
1288 finally {
1289 switchEnv.info.scope.leave();
1290 }
1291 }
1292 // where
1293 /** Add any variables defined in stats to the switch scope. */
1294 private static void addVars(List<JCStatement> stats, Scope switchScope) {
1295 for (;stats.nonEmpty(); stats = stats.tail) {
1296 JCTree stat = stats.head;
1297 if (stat.hasTag(VARDEF))
1298 switchScope.enter(((JCVariableDecl) stat).sym);
1299 }
1300 }
1301 // where
1302 /** Return the selected enumeration constant symbol, or null. */
1303 private Symbol enumConstant(JCTree tree, Type enumType) {
1304 if (!tree.hasTag(IDENT)) {
1305 log.error(tree.pos(), "enum.label.must.be.unqualified.enum");
1306 return syms.errSymbol;
1307 }
1308 JCIdent ident = (JCIdent)tree;
1309 Name name = ident.name;
1310 for (Scope.Entry e = enumType.tsym.members().lookup(name);
1311 e.scope != null; e = e.next()) {
1312 if (e.sym.kind == VAR) {
1313 Symbol s = ident.sym = e.sym;
1314 ((VarSymbol)s).getConstValue(); // ensure initializer is evaluated
1315 ident.type = s.type;
1316 return ((s.flags_field & Flags.ENUM) == 0)
1317 ? null : s;
1318 }
1319 }
1320 return null;
1321 }
1323 public void visitSynchronized(JCSynchronized tree) {
1324 chk.checkRefType(tree.pos(), attribExpr(tree.lock, env));
1325 attribStat(tree.body, env);
1326 result = null;
1327 }
1329 public void visitTry(JCTry tree) {
1330 // Create a new local environment with a local
1331 Env<AttrContext> localEnv = env.dup(tree, env.info.dup(env.info.scope.dup()));
1332 try {
1333 boolean isTryWithResource = tree.resources.nonEmpty();
1334 // Create a nested environment for attributing the try block if needed
1335 Env<AttrContext> tryEnv = isTryWithResource ?
1336 env.dup(tree, localEnv.info.dup(localEnv.info.scope.dup())) :
1337 localEnv;
1338 try {
1339 // Attribute resource declarations
1340 for (JCTree resource : tree.resources) {
1341 CheckContext twrContext = new Check.NestedCheckContext(resultInfo.checkContext) {
1342 @Override
1343 public void report(DiagnosticPosition pos, JCDiagnostic details) {
1344 chk.basicHandler.report(pos, diags.fragment("try.not.applicable.to.type", details));
1345 }
1346 };
1347 ResultInfo twrResult = new ResultInfo(VAL, syms.autoCloseableType, twrContext);
1348 if (resource.hasTag(VARDEF)) {
1349 attribStat(resource, tryEnv);
1350 twrResult.check(resource, resource.type);
1352 //check that resource type cannot throw InterruptedException
1353 checkAutoCloseable(resource.pos(), localEnv, resource.type);
1355 VarSymbol var = ((JCVariableDecl) resource).sym;
1356 var.setData(ElementKind.RESOURCE_VARIABLE);
1357 } else {
1358 attribTree(resource, tryEnv, twrResult);
1359 }
1360 }
1361 // Attribute body
1362 attribStat(tree.body, tryEnv);
1363 } finally {
1364 if (isTryWithResource)
1365 tryEnv.info.scope.leave();
1366 }
1368 // Attribute catch clauses
1369 for (List<JCCatch> l = tree.catchers; l.nonEmpty(); l = l.tail) {
1370 JCCatch c = l.head;
1371 Env<AttrContext> catchEnv =
1372 localEnv.dup(c, localEnv.info.dup(localEnv.info.scope.dup()));
1373 try {
1374 Type ctype = attribStat(c.param, catchEnv);
1375 if (TreeInfo.isMultiCatch(c)) {
1376 //multi-catch parameter is implicitly marked as final
1377 c.param.sym.flags_field |= FINAL | UNION;
1378 }
1379 if (c.param.sym.kind == Kinds.VAR) {
1380 c.param.sym.setData(ElementKind.EXCEPTION_PARAMETER);
1381 }
1382 chk.checkType(c.param.vartype.pos(),
1383 chk.checkClassType(c.param.vartype.pos(), ctype),
1384 syms.throwableType);
1385 attribStat(c.body, catchEnv);
1386 } finally {
1387 catchEnv.info.scope.leave();
1388 }
1389 }
1391 // Attribute finalizer
1392 if (tree.finalizer != null) attribStat(tree.finalizer, localEnv);
1393 result = null;
1394 }
1395 finally {
1396 localEnv.info.scope.leave();
1397 }
1398 }
1400 void checkAutoCloseable(DiagnosticPosition pos, Env<AttrContext> env, Type resource) {
1401 if (!resource.isErroneous() &&
1402 types.asSuper(resource, syms.autoCloseableType.tsym) != null &&
1403 !types.isSameType(resource, syms.autoCloseableType)) { // Don't emit warning for AutoCloseable itself
1404 Symbol close = syms.noSymbol;
1405 Log.DiagnosticHandler discardHandler = new Log.DiscardDiagnosticHandler(log);
1406 try {
1407 close = rs.resolveQualifiedMethod(pos,
1408 env,
1409 resource,
1410 names.close,
1411 List.<Type>nil(),
1412 List.<Type>nil());
1413 }
1414 finally {
1415 log.popDiagnosticHandler(discardHandler);
1416 }
1417 if (close.kind == MTH &&
1418 close.overrides(syms.autoCloseableClose, resource.tsym, types, true) &&
1419 chk.isHandled(syms.interruptedExceptionType, types.memberType(resource, close).getThrownTypes()) &&
1420 env.info.lint.isEnabled(LintCategory.TRY)) {
1421 log.warning(LintCategory.TRY, pos, "try.resource.throws.interrupted.exc", resource);
1422 }
1423 }
1424 }
1426 public void visitConditional(JCConditional tree) {
1427 Type condtype = attribExpr(tree.cond, env, syms.booleanType);
1429 tree.polyKind = (!allowPoly ||
1430 pt().hasTag(NONE) && pt() != Type.recoveryType ||
1431 isBooleanOrNumeric(env, tree)) ?
1432 PolyKind.STANDALONE : PolyKind.POLY;
1434 if (tree.polyKind == PolyKind.POLY && resultInfo.pt.hasTag(VOID)) {
1435 //cannot get here (i.e. it means we are returning from void method - which is already an error)
1436 resultInfo.checkContext.report(tree, diags.fragment("conditional.target.cant.be.void"));
1437 result = tree.type = types.createErrorType(resultInfo.pt);
1438 return;
1439 }
1441 ResultInfo condInfo = tree.polyKind == PolyKind.STANDALONE ?
1442 unknownExprInfo :
1443 resultInfo.dup(new Check.NestedCheckContext(resultInfo.checkContext) {
1444 //this will use enclosing check context to check compatibility of
1445 //subexpression against target type; if we are in a method check context,
1446 //depending on whether boxing is allowed, we could have incompatibilities
1447 @Override
1448 public void report(DiagnosticPosition pos, JCDiagnostic details) {
1449 enclosingContext.report(pos, diags.fragment("incompatible.type.in.conditional", details));
1450 }
1451 });
1453 Type truetype = attribTree(tree.truepart, env, condInfo);
1454 Type falsetype = attribTree(tree.falsepart, env, condInfo);
1456 Type owntype = (tree.polyKind == PolyKind.STANDALONE) ? condType(tree, truetype, falsetype) : pt();
1457 if (condtype.constValue() != null &&
1458 truetype.constValue() != null &&
1459 falsetype.constValue() != null &&
1460 !owntype.hasTag(NONE)) {
1461 //constant folding
1462 owntype = cfolder.coerce(condtype.isTrue() ? truetype : falsetype, owntype);
1463 }
1464 result = check(tree, owntype, VAL, resultInfo);
1465 }
1466 //where
1467 private boolean isBooleanOrNumeric(Env<AttrContext> env, JCExpression tree) {
1468 switch (tree.getTag()) {
1469 case LITERAL: return ((JCLiteral)tree).typetag.isSubRangeOf(DOUBLE) ||
1470 ((JCLiteral)tree).typetag == BOOLEAN ||
1471 ((JCLiteral)tree).typetag == BOT;
1472 case LAMBDA: case REFERENCE: return false;
1473 case PARENS: return isBooleanOrNumeric(env, ((JCParens)tree).expr);
1474 case CONDEXPR:
1475 JCConditional condTree = (JCConditional)tree;
1476 return isBooleanOrNumeric(env, condTree.truepart) &&
1477 isBooleanOrNumeric(env, condTree.falsepart);
1478 case APPLY:
1479 JCMethodInvocation speculativeMethodTree =
1480 (JCMethodInvocation)deferredAttr.attribSpeculative(tree, env, unknownExprInfo);
1481 Type owntype = TreeInfo.symbol(speculativeMethodTree.meth).type.getReturnType();
1482 return types.unboxedTypeOrType(owntype).isPrimitive();
1483 case NEWCLASS:
1484 JCExpression className =
1485 removeClassParams.translate(((JCNewClass)tree).clazz);
1486 JCExpression speculativeNewClassTree =
1487 (JCExpression)deferredAttr.attribSpeculative(className, env, unknownTypeInfo);
1488 return types.unboxedTypeOrType(speculativeNewClassTree.type).isPrimitive();
1489 default:
1490 Type speculativeType = deferredAttr.attribSpeculative(tree, env, unknownExprInfo).type;
1491 speculativeType = types.unboxedTypeOrType(speculativeType);
1492 return speculativeType.isPrimitive();
1493 }
1494 }
1495 //where
1496 TreeTranslator removeClassParams = new TreeTranslator() {
1497 @Override
1498 public void visitTypeApply(JCTypeApply tree) {
1499 result = translate(tree.clazz);
1500 }
1501 };
1503 /** Compute the type of a conditional expression, after
1504 * checking that it exists. See JLS 15.25. Does not take into
1505 * account the special case where condition and both arms
1506 * are constants.
1507 *
1508 * @param pos The source position to be used for error
1509 * diagnostics.
1510 * @param thentype The type of the expression's then-part.
1511 * @param elsetype The type of the expression's else-part.
1512 */
1513 private Type condType(DiagnosticPosition pos,
1514 Type thentype, Type elsetype) {
1515 // If same type, that is the result
1516 if (types.isSameType(thentype, elsetype))
1517 return thentype.baseType();
1519 Type thenUnboxed = (!allowBoxing || thentype.isPrimitive())
1520 ? thentype : types.unboxedType(thentype);
1521 Type elseUnboxed = (!allowBoxing || elsetype.isPrimitive())
1522 ? elsetype : types.unboxedType(elsetype);
1524 // Otherwise, if both arms can be converted to a numeric
1525 // type, return the least numeric type that fits both arms
1526 // (i.e. return larger of the two, or return int if one
1527 // arm is short, the other is char).
1528 if (thenUnboxed.isPrimitive() && elseUnboxed.isPrimitive()) {
1529 // If one arm has an integer subrange type (i.e., byte,
1530 // short, or char), and the other is an integer constant
1531 // that fits into the subrange, return the subrange type.
1532 if (thenUnboxed.getTag().isStrictSubRangeOf(INT) &&
1533 elseUnboxed.hasTag(INT) &&
1534 types.isAssignable(elseUnboxed, thenUnboxed)) {
1535 return thenUnboxed.baseType();
1536 }
1537 if (elseUnboxed.getTag().isStrictSubRangeOf(INT) &&
1538 thenUnboxed.hasTag(INT) &&
1539 types.isAssignable(thenUnboxed, elseUnboxed)) {
1540 return elseUnboxed.baseType();
1541 }
1543 for (TypeTag tag : primitiveTags) {
1544 Type candidate = syms.typeOfTag[tag.ordinal()];
1545 if (types.isSubtype(thenUnboxed, candidate) &&
1546 types.isSubtype(elseUnboxed, candidate)) {
1547 return candidate;
1548 }
1549 }
1550 }
1552 // Those were all the cases that could result in a primitive
1553 if (allowBoxing) {
1554 if (thentype.isPrimitive())
1555 thentype = types.boxedClass(thentype).type;
1556 if (elsetype.isPrimitive())
1557 elsetype = types.boxedClass(elsetype).type;
1558 }
1560 if (types.isSubtype(thentype, elsetype))
1561 return elsetype.baseType();
1562 if (types.isSubtype(elsetype, thentype))
1563 return thentype.baseType();
1565 if (!allowBoxing || thentype.hasTag(VOID) || elsetype.hasTag(VOID)) {
1566 log.error(pos, "neither.conditional.subtype",
1567 thentype, elsetype);
1568 return thentype.baseType();
1569 }
1571 // both are known to be reference types. The result is
1572 // lub(thentype,elsetype). This cannot fail, as it will
1573 // always be possible to infer "Object" if nothing better.
1574 return types.lub(thentype.baseType(), elsetype.baseType());
1575 }
1577 final static TypeTag[] primitiveTags = new TypeTag[]{
1578 BYTE,
1579 CHAR,
1580 SHORT,
1581 INT,
1582 LONG,
1583 FLOAT,
1584 DOUBLE,
1585 BOOLEAN,
1586 };
1588 public void visitIf(JCIf tree) {
1589 attribExpr(tree.cond, env, syms.booleanType);
1590 attribStat(tree.thenpart, env);
1591 if (tree.elsepart != null)
1592 attribStat(tree.elsepart, env);
1593 chk.checkEmptyIf(tree);
1594 result = null;
1595 }
1597 public void visitExec(JCExpressionStatement tree) {
1598 //a fresh environment is required for 292 inference to work properly ---
1599 //see Infer.instantiatePolymorphicSignatureInstance()
1600 Env<AttrContext> localEnv = env.dup(tree);
1601 attribExpr(tree.expr, localEnv);
1602 result = null;
1603 }
1605 public void visitBreak(JCBreak tree) {
1606 tree.target = findJumpTarget(tree.pos(), tree.getTag(), tree.label, env);
1607 result = null;
1608 }
1610 public void visitContinue(JCContinue tree) {
1611 tree.target = findJumpTarget(tree.pos(), tree.getTag(), tree.label, env);
1612 result = null;
1613 }
1614 //where
1615 /** Return the target of a break or continue statement, if it exists,
1616 * report an error if not.
1617 * Note: The target of a labelled break or continue is the
1618 * (non-labelled) statement tree referred to by the label,
1619 * not the tree representing the labelled statement itself.
1620 *
1621 * @param pos The position to be used for error diagnostics
1622 * @param tag The tag of the jump statement. This is either
1623 * Tree.BREAK or Tree.CONTINUE.
1624 * @param label The label of the jump statement, or null if no
1625 * label is given.
1626 * @param env The environment current at the jump statement.
1627 */
1628 private JCTree findJumpTarget(DiagnosticPosition pos,
1629 JCTree.Tag tag,
1630 Name label,
1631 Env<AttrContext> env) {
1632 // Search environments outwards from the point of jump.
1633 Env<AttrContext> env1 = env;
1634 LOOP:
1635 while (env1 != null) {
1636 switch (env1.tree.getTag()) {
1637 case LABELLED:
1638 JCLabeledStatement labelled = (JCLabeledStatement)env1.tree;
1639 if (label == labelled.label) {
1640 // If jump is a continue, check that target is a loop.
1641 if (tag == CONTINUE) {
1642 if (!labelled.body.hasTag(DOLOOP) &&
1643 !labelled.body.hasTag(WHILELOOP) &&
1644 !labelled.body.hasTag(FORLOOP) &&
1645 !labelled.body.hasTag(FOREACHLOOP))
1646 log.error(pos, "not.loop.label", label);
1647 // Found labelled statement target, now go inwards
1648 // to next non-labelled tree.
1649 return TreeInfo.referencedStatement(labelled);
1650 } else {
1651 return labelled;
1652 }
1653 }
1654 break;
1655 case DOLOOP:
1656 case WHILELOOP:
1657 case FORLOOP:
1658 case FOREACHLOOP:
1659 if (label == null) return env1.tree;
1660 break;
1661 case SWITCH:
1662 if (label == null && tag == BREAK) return env1.tree;
1663 break;
1664 case LAMBDA:
1665 case METHODDEF:
1666 case CLASSDEF:
1667 break LOOP;
1668 default:
1669 }
1670 env1 = env1.next;
1671 }
1672 if (label != null)
1673 log.error(pos, "undef.label", label);
1674 else if (tag == CONTINUE)
1675 log.error(pos, "cont.outside.loop");
1676 else
1677 log.error(pos, "break.outside.switch.loop");
1678 return null;
1679 }
1681 public void visitReturn(JCReturn tree) {
1682 // Check that there is an enclosing method which is
1683 // nested within than the enclosing class.
1684 if (env.info.returnResult == null) {
1685 log.error(tree.pos(), "ret.outside.meth");
1686 } else {
1687 // Attribute return expression, if it exists, and check that
1688 // it conforms to result type of enclosing method.
1689 if (tree.expr != null) {
1690 if (env.info.returnResult.pt.hasTag(VOID)) {
1691 env.info.returnResult.checkContext.report(tree.expr.pos(),
1692 diags.fragment("unexpected.ret.val"));
1693 }
1694 attribTree(tree.expr, env, env.info.returnResult);
1695 } else if (!env.info.returnResult.pt.hasTag(VOID) &&
1696 !env.info.returnResult.pt.hasTag(NONE)) {
1697 env.info.returnResult.checkContext.report(tree.pos(),
1698 diags.fragment("missing.ret.val"));
1699 }
1700 }
1701 result = null;
1702 }
1704 public void visitThrow(JCThrow tree) {
1705 Type owntype = attribExpr(tree.expr, env, allowPoly ? Type.noType : syms.throwableType);
1706 if (allowPoly) {
1707 chk.checkType(tree, owntype, syms.throwableType);
1708 }
1709 result = null;
1710 }
1712 public void visitAssert(JCAssert tree) {
1713 attribExpr(tree.cond, env, syms.booleanType);
1714 if (tree.detail != null) {
1715 chk.checkNonVoid(tree.detail.pos(), attribExpr(tree.detail, env));
1716 }
1717 result = null;
1718 }
1720 /** Visitor method for method invocations.
1721 * NOTE: The method part of an application will have in its type field
1722 * the return type of the method, not the method's type itself!
1723 */
1724 public void visitApply(JCMethodInvocation tree) {
1725 // The local environment of a method application is
1726 // a new environment nested in the current one.
1727 Env<AttrContext> localEnv = env.dup(tree, env.info.dup());
1729 // The types of the actual method arguments.
1730 List<Type> argtypes;
1732 // The types of the actual method type arguments.
1733 List<Type> typeargtypes = null;
1735 Name methName = TreeInfo.name(tree.meth);
1737 boolean isConstructorCall =
1738 methName == names._this || methName == names._super;
1740 ListBuffer<Type> argtypesBuf = ListBuffer.lb();
1741 if (isConstructorCall) {
1742 // We are seeing a ...this(...) or ...super(...) call.
1743 // Check that this is the first statement in a constructor.
1744 if (checkFirstConstructorStat(tree, env)) {
1746 // Record the fact
1747 // that this is a constructor call (using isSelfCall).
1748 localEnv.info.isSelfCall = true;
1750 // Attribute arguments, yielding list of argument types.
1751 attribArgs(tree.args, localEnv, argtypesBuf);
1752 argtypes = argtypesBuf.toList();
1753 typeargtypes = attribTypes(tree.typeargs, localEnv);
1755 // Variable `site' points to the class in which the called
1756 // constructor is defined.
1757 Type site = env.enclClass.sym.type;
1758 if (methName == names._super) {
1759 if (site == syms.objectType) {
1760 log.error(tree.meth.pos(), "no.superclass", site);
1761 site = types.createErrorType(syms.objectType);
1762 } else {
1763 site = types.supertype(site);
1764 }
1765 }
1767 if (site.hasTag(CLASS)) {
1768 Type encl = site.getEnclosingType();
1769 while (encl != null && encl.hasTag(TYPEVAR))
1770 encl = encl.getUpperBound();
1771 if (encl.hasTag(CLASS)) {
1772 // we are calling a nested class
1774 if (tree.meth.hasTag(SELECT)) {
1775 JCTree qualifier = ((JCFieldAccess) tree.meth).selected;
1777 // We are seeing a prefixed call, of the form
1778 // <expr>.super(...).
1779 // Check that the prefix expression conforms
1780 // to the outer instance type of the class.
1781 chk.checkRefType(qualifier.pos(),
1782 attribExpr(qualifier, localEnv,
1783 encl));
1784 } else if (methName == names._super) {
1785 // qualifier omitted; check for existence
1786 // of an appropriate implicit qualifier.
1787 rs.resolveImplicitThis(tree.meth.pos(),
1788 localEnv, site, true);
1789 }
1790 } else if (tree.meth.hasTag(SELECT)) {
1791 log.error(tree.meth.pos(), "illegal.qual.not.icls",
1792 site.tsym);
1793 }
1795 // if we're calling a java.lang.Enum constructor,
1796 // prefix the implicit String and int parameters
1797 if (site.tsym == syms.enumSym && allowEnums)
1798 argtypes = argtypes.prepend(syms.intType).prepend(syms.stringType);
1800 // Resolve the called constructor under the assumption
1801 // that we are referring to a superclass instance of the
1802 // current instance (JLS ???).
1803 boolean selectSuperPrev = localEnv.info.selectSuper;
1804 localEnv.info.selectSuper = true;
1805 localEnv.info.pendingResolutionPhase = null;
1806 Symbol sym = rs.resolveConstructor(
1807 tree.meth.pos(), localEnv, site, argtypes, typeargtypes);
1808 localEnv.info.selectSuper = selectSuperPrev;
1810 // Set method symbol to resolved constructor...
1811 TreeInfo.setSymbol(tree.meth, sym);
1813 // ...and check that it is legal in the current context.
1814 // (this will also set the tree's type)
1815 Type mpt = newMethodTemplate(resultInfo.pt, argtypes, typeargtypes);
1816 checkId(tree.meth, site, sym, localEnv, new ResultInfo(MTH, mpt));
1817 }
1818 // Otherwise, `site' is an error type and we do nothing
1819 }
1820 result = tree.type = syms.voidType;
1821 } else {
1822 // Otherwise, we are seeing a regular method call.
1823 // Attribute the arguments, yielding list of argument types, ...
1824 int kind = attribArgs(tree.args, localEnv, argtypesBuf);
1825 argtypes = argtypesBuf.toList();
1826 typeargtypes = attribAnyTypes(tree.typeargs, localEnv);
1828 // ... and attribute the method using as a prototype a methodtype
1829 // whose formal argument types is exactly the list of actual
1830 // arguments (this will also set the method symbol).
1831 Type mpt = newMethodTemplate(resultInfo.pt, argtypes, typeargtypes);
1832 localEnv.info.pendingResolutionPhase = null;
1833 Type mtype = attribTree(tree.meth, localEnv, new ResultInfo(kind, mpt, resultInfo.checkContext));
1835 // Compute the result type.
1836 Type restype = mtype.getReturnType();
1837 if (restype.hasTag(WILDCARD))
1838 throw new AssertionError(mtype);
1840 Type qualifier = (tree.meth.hasTag(SELECT))
1841 ? ((JCFieldAccess) tree.meth).selected.type
1842 : env.enclClass.sym.type;
1843 restype = adjustMethodReturnType(qualifier, methName, argtypes, restype);
1845 chk.checkRefTypes(tree.typeargs, typeargtypes);
1847 // Check that value of resulting type is admissible in the
1848 // current context. Also, capture the return type
1849 result = check(tree, capture(restype), VAL, resultInfo);
1850 }
1851 chk.validate(tree.typeargs, localEnv);
1852 }
1853 //where
1854 Type adjustMethodReturnType(Type qualifierType, Name methodName, List<Type> argtypes, Type restype) {
1855 if (allowCovariantReturns &&
1856 methodName == names.clone &&
1857 types.isArray(qualifierType)) {
1858 // as a special case, array.clone() has a result that is
1859 // the same as static type of the array being cloned
1860 return qualifierType;
1861 } else if (allowGenerics &&
1862 methodName == names.getClass &&
1863 argtypes.isEmpty()) {
1864 // as a special case, x.getClass() has type Class<? extends |X|>
1865 return new ClassType(restype.getEnclosingType(),
1866 List.<Type>of(new WildcardType(types.erasure(qualifierType),
1867 BoundKind.EXTENDS,
1868 syms.boundClass)),
1869 restype.tsym);
1870 } else {
1871 return restype;
1872 }
1873 }
1875 /** Check that given application node appears as first statement
1876 * in a constructor call.
1877 * @param tree The application node
1878 * @param env The environment current at the application.
1879 */
1880 boolean checkFirstConstructorStat(JCMethodInvocation tree, Env<AttrContext> env) {
1881 JCMethodDecl enclMethod = env.enclMethod;
1882 if (enclMethod != null && enclMethod.name == names.init) {
1883 JCBlock body = enclMethod.body;
1884 if (body.stats.head.hasTag(EXEC) &&
1885 ((JCExpressionStatement) body.stats.head).expr == tree)
1886 return true;
1887 }
1888 log.error(tree.pos(),"call.must.be.first.stmt.in.ctor",
1889 TreeInfo.name(tree.meth));
1890 return false;
1891 }
1893 /** Obtain a method type with given argument types.
1894 */
1895 Type newMethodTemplate(Type restype, List<Type> argtypes, List<Type> typeargtypes) {
1896 MethodType mt = new MethodType(argtypes, restype, List.<Type>nil(), syms.methodClass);
1897 return (typeargtypes == null) ? mt : (Type)new ForAll(typeargtypes, mt);
1898 }
1900 public void visitNewClass(final JCNewClass tree) {
1901 Type owntype = types.createErrorType(tree.type);
1903 // The local environment of a class creation is
1904 // a new environment nested in the current one.
1905 Env<AttrContext> localEnv = env.dup(tree, env.info.dup());
1907 // The anonymous inner class definition of the new expression,
1908 // if one is defined by it.
1909 JCClassDecl cdef = tree.def;
1911 // If enclosing class is given, attribute it, and
1912 // complete class name to be fully qualified
1913 JCExpression clazz = tree.clazz; // Class field following new
1914 JCExpression clazzid; // Identifier in class field
1915 JCAnnotatedType annoclazzid; // Annotated type enclosing clazzid
1916 annoclazzid = null;
1918 if (clazz.hasTag(TYPEAPPLY)) {
1919 clazzid = ((JCTypeApply) clazz).clazz;
1920 if (clazzid.hasTag(ANNOTATED_TYPE)) {
1921 annoclazzid = (JCAnnotatedType) clazzid;
1922 clazzid = annoclazzid.underlyingType;
1923 }
1924 } else {
1925 if (clazz.hasTag(ANNOTATED_TYPE)) {
1926 annoclazzid = (JCAnnotatedType) clazz;
1927 clazzid = annoclazzid.underlyingType;
1928 } else {
1929 clazzid = clazz;
1930 }
1931 }
1933 JCExpression clazzid1 = clazzid; // The same in fully qualified form
1935 if (tree.encl != null) {
1936 // We are seeing a qualified new, of the form
1937 // <expr>.new C <...> (...) ...
1938 // In this case, we let clazz stand for the name of the
1939 // allocated class C prefixed with the type of the qualifier
1940 // expression, so that we can
1941 // resolve it with standard techniques later. I.e., if
1942 // <expr> has type T, then <expr>.new C <...> (...)
1943 // yields a clazz T.C.
1944 Type encltype = chk.checkRefType(tree.encl.pos(),
1945 attribExpr(tree.encl, env));
1946 // TODO 308: in <expr>.new C, do we also want to add the type annotations
1947 // from expr to the combined type, or not? Yes, do this.
1948 clazzid1 = make.at(clazz.pos).Select(make.Type(encltype),
1949 ((JCIdent) clazzid).name);
1951 EndPosTable endPosTable = this.env.toplevel.endPositions;
1952 endPosTable.storeEnd(clazzid1, tree.getEndPosition(endPosTable));
1953 if (clazz.hasTag(ANNOTATED_TYPE)) {
1954 JCAnnotatedType annoType = (JCAnnotatedType) clazz;
1955 List<JCAnnotation> annos = annoType.annotations;
1957 if (annoType.underlyingType.hasTag(TYPEAPPLY)) {
1958 clazzid1 = make.at(tree.pos).
1959 TypeApply(clazzid1,
1960 ((JCTypeApply) clazz).arguments);
1961 }
1963 clazzid1 = make.at(tree.pos).
1964 AnnotatedType(annos, clazzid1);
1965 } else if (clazz.hasTag(TYPEAPPLY)) {
1966 clazzid1 = make.at(tree.pos).
1967 TypeApply(clazzid1,
1968 ((JCTypeApply) clazz).arguments);
1969 }
1971 clazz = clazzid1;
1972 }
1974 // Attribute clazz expression and store
1975 // symbol + type back into the attributed tree.
1976 Type clazztype = TreeInfo.isEnumInit(env.tree) ?
1977 attribIdentAsEnumType(env, (JCIdent)clazz) :
1978 attribType(clazz, env);
1980 clazztype = chk.checkDiamond(tree, clazztype);
1981 chk.validate(clazz, localEnv);
1982 if (tree.encl != null) {
1983 // We have to work in this case to store
1984 // symbol + type back into the attributed tree.
1985 tree.clazz.type = clazztype;
1986 TreeInfo.setSymbol(clazzid, TreeInfo.symbol(clazzid1));
1987 clazzid.type = ((JCIdent) clazzid).sym.type;
1988 if (annoclazzid != null) {
1989 annoclazzid.type = clazzid.type;
1990 }
1991 if (!clazztype.isErroneous()) {
1992 if (cdef != null && clazztype.tsym.isInterface()) {
1993 log.error(tree.encl.pos(), "anon.class.impl.intf.no.qual.for.new");
1994 } else if (clazztype.tsym.isStatic()) {
1995 log.error(tree.encl.pos(), "qualified.new.of.static.class", clazztype.tsym);
1996 }
1997 }
1998 } else if (!clazztype.tsym.isInterface() &&
1999 clazztype.getEnclosingType().hasTag(CLASS)) {
2000 // Check for the existence of an apropos outer instance
2001 rs.resolveImplicitThis(tree.pos(), env, clazztype);
2002 }
2004 // Attribute constructor arguments.
2005 ListBuffer<Type> argtypesBuf = ListBuffer.lb();
2006 int pkind = attribArgs(tree.args, localEnv, argtypesBuf);
2007 List<Type> argtypes = argtypesBuf.toList();
2008 List<Type> typeargtypes = attribTypes(tree.typeargs, localEnv);
2010 // If we have made no mistakes in the class type...
2011 if (clazztype.hasTag(CLASS)) {
2012 // Enums may not be instantiated except implicitly
2013 if (allowEnums &&
2014 (clazztype.tsym.flags_field&Flags.ENUM) != 0 &&
2015 (!env.tree.hasTag(VARDEF) ||
2016 (((JCVariableDecl) env.tree).mods.flags&Flags.ENUM) == 0 ||
2017 ((JCVariableDecl) env.tree).init != tree))
2018 log.error(tree.pos(), "enum.cant.be.instantiated");
2019 // Check that class is not abstract
2020 if (cdef == null &&
2021 (clazztype.tsym.flags() & (ABSTRACT | INTERFACE)) != 0) {
2022 log.error(tree.pos(), "abstract.cant.be.instantiated",
2023 clazztype.tsym);
2024 } else if (cdef != null && clazztype.tsym.isInterface()) {
2025 // Check that no constructor arguments are given to
2026 // anonymous classes implementing an interface
2027 if (!argtypes.isEmpty())
2028 log.error(tree.args.head.pos(), "anon.class.impl.intf.no.args");
2030 if (!typeargtypes.isEmpty())
2031 log.error(tree.typeargs.head.pos(), "anon.class.impl.intf.no.typeargs");
2033 // Error recovery: pretend no arguments were supplied.
2034 argtypes = List.nil();
2035 typeargtypes = List.nil();
2036 } else if (TreeInfo.isDiamond(tree)) {
2037 ClassType site = new ClassType(clazztype.getEnclosingType(),
2038 clazztype.tsym.type.getTypeArguments(),
2039 clazztype.tsym);
2041 Env<AttrContext> diamondEnv = localEnv.dup(tree);
2042 diamondEnv.info.selectSuper = cdef != null;
2043 diamondEnv.info.pendingResolutionPhase = null;
2045 //if the type of the instance creation expression is a class type
2046 //apply method resolution inference (JLS 15.12.2.7). The return type
2047 //of the resolved constructor will be a partially instantiated type
2048 Symbol constructor = rs.resolveDiamond(tree.pos(),
2049 diamondEnv,
2050 site,
2051 argtypes,
2052 typeargtypes);
2053 tree.constructor = constructor.baseSymbol();
2055 final TypeSymbol csym = clazztype.tsym;
2056 ResultInfo diamondResult = new ResultInfo(MTH, newMethodTemplate(resultInfo.pt, argtypes, typeargtypes), new Check.NestedCheckContext(resultInfo.checkContext) {
2057 @Override
2058 public void report(DiagnosticPosition _unused, JCDiagnostic details) {
2059 enclosingContext.report(tree.clazz,
2060 diags.fragment("cant.apply.diamond.1", diags.fragment("diamond", csym), details));
2061 }
2062 });
2063 Type constructorType = tree.constructorType = types.createErrorType(clazztype);
2064 constructorType = checkId(tree, site,
2065 constructor,
2066 diamondEnv,
2067 diamondResult);
2069 tree.clazz.type = types.createErrorType(clazztype);
2070 if (!constructorType.isErroneous()) {
2071 tree.clazz.type = clazztype = constructorType.getReturnType();
2072 tree.constructorType = types.createMethodTypeWithReturn(constructorType, syms.voidType);
2073 }
2074 clazztype = chk.checkClassType(tree.clazz, tree.clazz.type, true);
2075 }
2077 // Resolve the called constructor under the assumption
2078 // that we are referring to a superclass instance of the
2079 // current instance (JLS ???).
2080 else {
2081 //the following code alters some of the fields in the current
2082 //AttrContext - hence, the current context must be dup'ed in
2083 //order to avoid downstream failures
2084 Env<AttrContext> rsEnv = localEnv.dup(tree);
2085 rsEnv.info.selectSuper = cdef != null;
2086 rsEnv.info.pendingResolutionPhase = null;
2087 tree.constructor = rs.resolveConstructor(
2088 tree.pos(), rsEnv, clazztype, argtypes, typeargtypes);
2089 if (cdef == null) { //do not check twice!
2090 tree.constructorType = checkId(tree,
2091 clazztype,
2092 tree.constructor,
2093 rsEnv,
2094 new ResultInfo(pkind, newMethodTemplate(syms.voidType, argtypes, typeargtypes)));
2095 if (rsEnv.info.lastResolveVarargs())
2096 Assert.check(tree.constructorType.isErroneous() || tree.varargsElement != null);
2097 }
2098 if (cdef == null &&
2099 !clazztype.isErroneous() &&
2100 clazztype.getTypeArguments().nonEmpty() &&
2101 findDiamonds) {
2102 findDiamond(localEnv, tree, clazztype);
2103 }
2104 }
2106 if (cdef != null) {
2107 // We are seeing an anonymous class instance creation.
2108 // In this case, the class instance creation
2109 // expression
2110 //
2111 // E.new <typeargs1>C<typargs2>(args) { ... }
2112 //
2113 // is represented internally as
2114 //
2115 // E . new <typeargs1>C<typargs2>(args) ( class <empty-name> { ... } ) .
2116 //
2117 // This expression is then *transformed* as follows:
2118 //
2119 // (1) add a STATIC flag to the class definition
2120 // if the current environment is static
2121 // (2) add an extends or implements clause
2122 // (3) add a constructor.
2123 //
2124 // For instance, if C is a class, and ET is the type of E,
2125 // the expression
2126 //
2127 // E.new <typeargs1>C<typargs2>(args) { ... }
2128 //
2129 // is translated to (where X is a fresh name and typarams is the
2130 // parameter list of the super constructor):
2131 //
2132 // new <typeargs1>X(<*nullchk*>E, args) where
2133 // X extends C<typargs2> {
2134 // <typarams> X(ET e, args) {
2135 // e.<typeargs1>super(args)
2136 // }
2137 // ...
2138 // }
2139 if (Resolve.isStatic(env)) cdef.mods.flags |= STATIC;
2141 if (clazztype.tsym.isInterface()) {
2142 cdef.implementing = List.of(clazz);
2143 } else {
2144 cdef.extending = clazz;
2145 }
2147 attribStat(cdef, localEnv);
2149 checkLambdaCandidate(tree, cdef.sym, clazztype);
2151 // If an outer instance is given,
2152 // prefix it to the constructor arguments
2153 // and delete it from the new expression
2154 if (tree.encl != null && !clazztype.tsym.isInterface()) {
2155 tree.args = tree.args.prepend(makeNullCheck(tree.encl));
2156 argtypes = argtypes.prepend(tree.encl.type);
2157 tree.encl = null;
2158 }
2160 // Reassign clazztype and recompute constructor.
2161 clazztype = cdef.sym.type;
2162 Symbol sym = tree.constructor = rs.resolveConstructor(
2163 tree.pos(), localEnv, clazztype, argtypes, typeargtypes);
2164 Assert.check(sym.kind < AMBIGUOUS);
2165 tree.constructor = sym;
2166 tree.constructorType = checkId(tree,
2167 clazztype,
2168 tree.constructor,
2169 localEnv,
2170 new ResultInfo(pkind, newMethodTemplate(syms.voidType, argtypes, typeargtypes)));
2171 } else {
2172 if (tree.clazz.hasTag(ANNOTATED_TYPE)) {
2173 checkForDeclarationAnnotations(((JCAnnotatedType) tree.clazz).annotations,
2174 tree.clazz.type.tsym);
2175 }
2176 }
2178 if (tree.constructor != null && tree.constructor.kind == MTH)
2179 owntype = clazztype;
2180 }
2181 result = check(tree, owntype, VAL, resultInfo);
2182 chk.validate(tree.typeargs, localEnv);
2183 }
2184 //where
2185 void findDiamond(Env<AttrContext> env, JCNewClass tree, Type clazztype) {
2186 JCTypeApply ta = (JCTypeApply)tree.clazz;
2187 List<JCExpression> prevTypeargs = ta.arguments;
2188 try {
2189 //create a 'fake' diamond AST node by removing type-argument trees
2190 ta.arguments = List.nil();
2191 ResultInfo findDiamondResult = new ResultInfo(VAL,
2192 resultInfo.checkContext.inferenceContext().free(resultInfo.pt) ? Type.noType : pt());
2193 Type inferred = deferredAttr.attribSpeculative(tree, env, findDiamondResult).type;
2194 Type polyPt = allowPoly ?
2195 syms.objectType :
2196 clazztype;
2197 if (!inferred.isErroneous() &&
2198 (allowPoly && pt() == Infer.anyPoly ?
2199 types.isSameType(inferred, clazztype) :
2200 types.isAssignable(inferred, pt().hasTag(NONE) ? polyPt : pt(), types.noWarnings))) {
2201 String key = types.isSameType(clazztype, inferred) ?
2202 "diamond.redundant.args" :
2203 "diamond.redundant.args.1";
2204 log.warning(tree.clazz.pos(), key, clazztype, inferred);
2205 }
2206 } finally {
2207 ta.arguments = prevTypeargs;
2208 }
2209 }
2211 private void checkLambdaCandidate(JCNewClass tree, ClassSymbol csym, Type clazztype) {
2212 if (allowLambda &&
2213 identifyLambdaCandidate &&
2214 clazztype.hasTag(CLASS) &&
2215 !pt().hasTag(NONE) &&
2216 types.isFunctionalInterface(clazztype.tsym)) {
2217 Symbol descriptor = types.findDescriptorSymbol(clazztype.tsym);
2218 int count = 0;
2219 boolean found = false;
2220 for (Symbol sym : csym.members().getElements()) {
2221 if ((sym.flags() & SYNTHETIC) != 0 ||
2222 sym.isConstructor()) continue;
2223 count++;
2224 if (sym.kind != MTH ||
2225 !sym.name.equals(descriptor.name)) continue;
2226 Type mtype = types.memberType(clazztype, sym);
2227 if (types.overrideEquivalent(mtype, types.memberType(clazztype, descriptor))) {
2228 found = true;
2229 }
2230 }
2231 if (found && count == 1) {
2232 log.note(tree.def, "potential.lambda.found");
2233 }
2234 }
2235 }
2237 private void checkForDeclarationAnnotations(List<? extends JCAnnotation> annotations,
2238 Symbol sym) {
2239 // Ensure that no declaration annotations are present.
2240 // Note that a tree type might be an AnnotatedType with
2241 // empty annotations, if only declaration annotations were given.
2242 // This method will raise an error for such a type.
2243 for (JCAnnotation ai : annotations) {
2244 if (TypeAnnotations.annotationType(syms, names, ai.attribute, sym) == TypeAnnotations.AnnotationType.DECLARATION) {
2245 log.error(ai.pos(), "annotation.type.not.applicable");
2246 }
2247 }
2248 }
2251 /** Make an attributed null check tree.
2252 */
2253 public JCExpression makeNullCheck(JCExpression arg) {
2254 // optimization: X.this is never null; skip null check
2255 Name name = TreeInfo.name(arg);
2256 if (name == names._this || name == names._super) return arg;
2258 JCTree.Tag optag = NULLCHK;
2259 JCUnary tree = make.at(arg.pos).Unary(optag, arg);
2260 tree.operator = syms.nullcheck;
2261 tree.type = arg.type;
2262 return tree;
2263 }
2265 public void visitNewArray(JCNewArray tree) {
2266 Type owntype = types.createErrorType(tree.type);
2267 Env<AttrContext> localEnv = env.dup(tree);
2268 Type elemtype;
2269 if (tree.elemtype != null) {
2270 elemtype = attribType(tree.elemtype, localEnv);
2271 chk.validate(tree.elemtype, localEnv);
2272 owntype = elemtype;
2273 for (List<JCExpression> l = tree.dims; l.nonEmpty(); l = l.tail) {
2274 attribExpr(l.head, localEnv, syms.intType);
2275 owntype = new ArrayType(owntype, syms.arrayClass);
2276 }
2277 if (tree.elemtype.hasTag(ANNOTATED_TYPE)) {
2278 checkForDeclarationAnnotations(((JCAnnotatedType) tree.elemtype).annotations,
2279 tree.elemtype.type.tsym);
2280 }
2281 } else {
2282 // we are seeing an untyped aggregate { ... }
2283 // this is allowed only if the prototype is an array
2284 if (pt().hasTag(ARRAY)) {
2285 elemtype = types.elemtype(pt());
2286 } else {
2287 if (!pt().hasTag(ERROR)) {
2288 log.error(tree.pos(), "illegal.initializer.for.type",
2289 pt());
2290 }
2291 elemtype = types.createErrorType(pt());
2292 }
2293 }
2294 if (tree.elems != null) {
2295 attribExprs(tree.elems, localEnv, elemtype);
2296 owntype = new ArrayType(elemtype, syms.arrayClass);
2297 }
2298 if (!types.isReifiable(elemtype))
2299 log.error(tree.pos(), "generic.array.creation");
2300 result = check(tree, owntype, VAL, resultInfo);
2301 }
2303 /*
2304 * A lambda expression can only be attributed when a target-type is available.
2305 * In addition, if the target-type is that of a functional interface whose
2306 * descriptor contains inference variables in argument position the lambda expression
2307 * is 'stuck' (see DeferredAttr).
2308 */
2309 @Override
2310 public void visitLambda(final JCLambda that) {
2311 if (pt().isErroneous() || (pt().hasTag(NONE) && pt() != Type.recoveryType)) {
2312 if (pt().hasTag(NONE)) {
2313 //lambda only allowed in assignment or method invocation/cast context
2314 log.error(that.pos(), "unexpected.lambda");
2315 }
2316 result = that.type = types.createErrorType(pt());
2317 return;
2318 }
2319 //create an environment for attribution of the lambda expression
2320 final Env<AttrContext> localEnv = lambdaEnv(that, env);
2321 boolean needsRecovery =
2322 resultInfo.checkContext.deferredAttrContext().mode == DeferredAttr.AttrMode.CHECK;
2323 try {
2324 Type target = pt();
2325 List<Type> explicitParamTypes = null;
2326 if (that.paramKind == JCLambda.ParameterKind.EXPLICIT) {
2327 //attribute lambda parameters
2328 attribStats(that.params, localEnv);
2329 explicitParamTypes = TreeInfo.types(that.params);
2330 target = infer.instantiateFunctionalInterface(that, target, explicitParamTypes, resultInfo.checkContext);
2331 }
2333 Type lambdaType;
2334 if (pt() != Type.recoveryType) {
2335 target = targetChecker.visit(target, that);
2336 lambdaType = types.findDescriptorType(target);
2337 } else {
2338 target = Type.recoveryType;
2339 lambdaType = fallbackDescriptorType(that);
2340 }
2342 setFunctionalInfo(localEnv, that, pt(), lambdaType, target, resultInfo.checkContext);
2344 if (lambdaType.hasTag(FORALL)) {
2345 //lambda expression target desc cannot be a generic method
2346 resultInfo.checkContext.report(that, diags.fragment("invalid.generic.lambda.target",
2347 lambdaType, kindName(target.tsym), target.tsym));
2348 result = that.type = types.createErrorType(pt());
2349 return;
2350 }
2352 if (that.paramKind == JCLambda.ParameterKind.IMPLICIT) {
2353 //add param type info in the AST
2354 List<Type> actuals = lambdaType.getParameterTypes();
2355 List<JCVariableDecl> params = that.params;
2357 boolean arityMismatch = false;
2359 while (params.nonEmpty()) {
2360 if (actuals.isEmpty()) {
2361 //not enough actuals to perform lambda parameter inference
2362 arityMismatch = true;
2363 }
2364 //reset previously set info
2365 Type argType = arityMismatch ?
2366 syms.errType :
2367 actuals.head;
2368 params.head.vartype = make.at(params.head).Type(argType);
2369 params.head.sym = null;
2370 actuals = actuals.isEmpty() ?
2371 actuals :
2372 actuals.tail;
2373 params = params.tail;
2374 }
2376 //attribute lambda parameters
2377 attribStats(that.params, localEnv);
2379 if (arityMismatch) {
2380 resultInfo.checkContext.report(that, diags.fragment("incompatible.arg.types.in.lambda"));
2381 result = that.type = types.createErrorType(target);
2382 return;
2383 }
2384 }
2386 //from this point on, no recovery is needed; if we are in assignment context
2387 //we will be able to attribute the whole lambda body, regardless of errors;
2388 //if we are in a 'check' method context, and the lambda is not compatible
2389 //with the target-type, it will be recovered anyway in Attr.checkId
2390 needsRecovery = false;
2392 FunctionalReturnContext funcContext = that.getBodyKind() == JCLambda.BodyKind.EXPRESSION ?
2393 new ExpressionLambdaReturnContext((JCExpression)that.getBody(), resultInfo.checkContext) :
2394 new FunctionalReturnContext(resultInfo.checkContext);
2396 ResultInfo bodyResultInfo = lambdaType.getReturnType() == Type.recoveryType ?
2397 recoveryInfo :
2398 new ResultInfo(VAL, lambdaType.getReturnType(), funcContext);
2399 localEnv.info.returnResult = bodyResultInfo;
2401 Log.DeferredDiagnosticHandler lambdaDeferredHandler = new Log.DeferredDiagnosticHandler(log);
2402 try {
2403 if (that.getBodyKind() == JCLambda.BodyKind.EXPRESSION) {
2404 attribTree(that.getBody(), localEnv, bodyResultInfo);
2405 } else {
2406 JCBlock body = (JCBlock)that.body;
2407 attribStats(body.stats, localEnv);
2408 }
2410 if (resultInfo.checkContext.deferredAttrContext().mode == AttrMode.SPECULATIVE) {
2411 //check for errors in lambda body
2412 for (JCDiagnostic deferredDiag : lambdaDeferredHandler.getDiagnostics()) {
2413 if (deferredDiag.getKind() == JCDiagnostic.Kind.ERROR) {
2414 resultInfo.checkContext
2415 .report(that, diags.fragment("bad.arg.types.in.lambda", TreeInfo.types(that.params),
2416 deferredDiag)); //hidden diag parameter
2417 //we mark the lambda as erroneous - this is crucial in the recovery step
2418 //as parameter-dependent type error won't be reported in that stage,
2419 //meaning that a lambda will be deemed erroeneous only if there is
2420 //a target-independent error (which will cause method diagnostic
2421 //to be skipped).
2422 result = that.type = types.createErrorType(target);
2423 return;
2424 }
2425 }
2426 }
2427 } finally {
2428 lambdaDeferredHandler.reportDeferredDiagnostics();
2429 log.popDiagnosticHandler(lambdaDeferredHandler);
2430 }
2432 result = check(that, target, VAL, resultInfo);
2434 boolean isSpeculativeRound =
2435 resultInfo.checkContext.deferredAttrContext().mode == DeferredAttr.AttrMode.SPECULATIVE;
2437 preFlow(that);
2438 flow.analyzeLambda(env, that, make, isSpeculativeRound);
2440 checkLambdaCompatible(that, lambdaType, resultInfo.checkContext, isSpeculativeRound);
2442 if (!isSpeculativeRound) {
2443 checkAccessibleTypes(that, localEnv, resultInfo.checkContext.inferenceContext(), lambdaType, target);
2444 }
2445 result = check(that, target, VAL, resultInfo);
2446 } catch (Types.FunctionDescriptorLookupError ex) {
2447 JCDiagnostic cause = ex.getDiagnostic();
2448 resultInfo.checkContext.report(that, cause);
2449 result = that.type = types.createErrorType(pt());
2450 return;
2451 } finally {
2452 localEnv.info.scope.leave();
2453 if (needsRecovery) {
2454 attribTree(that, env, recoveryInfo);
2455 }
2456 }
2457 }
2458 //where
2459 void preFlow(JCLambda tree) {
2460 new PostAttrAnalyzer() {
2461 @Override
2462 public void scan(JCTree tree) {
2463 if (tree == null ||
2464 (tree.type != null &&
2465 tree.type == Type.stuckType)) {
2466 //don't touch stuck expressions!
2467 return;
2468 }
2469 super.scan(tree);
2470 }
2471 }.scan(tree);
2472 }
2474 Types.MapVisitor<DiagnosticPosition> targetChecker = new Types.MapVisitor<DiagnosticPosition>() {
2476 @Override
2477 public Type visitClassType(ClassType t, DiagnosticPosition pos) {
2478 return t.isCompound() ?
2479 visitIntersectionClassType((IntersectionClassType)t, pos) : t;
2480 }
2482 public Type visitIntersectionClassType(IntersectionClassType ict, DiagnosticPosition pos) {
2483 Symbol desc = types.findDescriptorSymbol(makeNotionalInterface(ict));
2484 Type target = null;
2485 for (Type bound : ict.getExplicitComponents()) {
2486 TypeSymbol boundSym = bound.tsym;
2487 if (types.isFunctionalInterface(boundSym) &&
2488 types.findDescriptorSymbol(boundSym) == desc) {
2489 target = bound;
2490 } else if (!boundSym.isInterface() || (boundSym.flags() & ANNOTATION) != 0) {
2491 //bound must be an interface
2492 reportIntersectionError(pos, "not.an.intf.component", boundSym);
2493 }
2494 }
2495 return target != null ?
2496 target :
2497 ict.getExplicitComponents().head; //error recovery
2498 }
2500 private TypeSymbol makeNotionalInterface(IntersectionClassType ict) {
2501 ListBuffer<Type> targs = ListBuffer.lb();
2502 ListBuffer<Type> supertypes = ListBuffer.lb();
2503 for (Type i : ict.interfaces_field) {
2504 if (i.isParameterized()) {
2505 targs.appendList(i.tsym.type.allparams());
2506 }
2507 supertypes.append(i.tsym.type);
2508 }
2509 IntersectionClassType notionalIntf =
2510 (IntersectionClassType)types.makeCompoundType(supertypes.toList());
2511 notionalIntf.allparams_field = targs.toList();
2512 notionalIntf.tsym.flags_field |= INTERFACE;
2513 return notionalIntf.tsym;
2514 }
2516 private void reportIntersectionError(DiagnosticPosition pos, String key, Object... args) {
2517 resultInfo.checkContext.report(pos, diags.fragment("bad.intersection.target.for.functional.expr",
2518 diags.fragment(key, args)));
2519 }
2520 };
2522 private Type fallbackDescriptorType(JCExpression tree) {
2523 switch (tree.getTag()) {
2524 case LAMBDA:
2525 JCLambda lambda = (JCLambda)tree;
2526 List<Type> argtypes = List.nil();
2527 for (JCVariableDecl param : lambda.params) {
2528 argtypes = param.vartype != null ?
2529 argtypes.append(param.vartype.type) :
2530 argtypes.append(syms.errType);
2531 }
2532 return new MethodType(argtypes, Type.recoveryType,
2533 List.of(syms.throwableType), syms.methodClass);
2534 case REFERENCE:
2535 return new MethodType(List.<Type>nil(), Type.recoveryType,
2536 List.of(syms.throwableType), syms.methodClass);
2537 default:
2538 Assert.error("Cannot get here!");
2539 }
2540 return null;
2541 }
2543 private void checkAccessibleTypes(final DiagnosticPosition pos, final Env<AttrContext> env,
2544 final InferenceContext inferenceContext, final Type... ts) {
2545 checkAccessibleTypes(pos, env, inferenceContext, List.from(ts));
2546 }
2548 private void checkAccessibleTypes(final DiagnosticPosition pos, final Env<AttrContext> env,
2549 final InferenceContext inferenceContext, final List<Type> ts) {
2550 if (inferenceContext.free(ts)) {
2551 inferenceContext.addFreeTypeListener(ts, new FreeTypeListener() {
2552 @Override
2553 public void typesInferred(InferenceContext inferenceContext) {
2554 checkAccessibleTypes(pos, env, inferenceContext, inferenceContext.asInstTypes(ts));
2555 }
2556 });
2557 } else {
2558 for (Type t : ts) {
2559 rs.checkAccessibleType(env, t);
2560 }
2561 }
2562 }
2564 /**
2565 * Lambda/method reference have a special check context that ensures
2566 * that i.e. a lambda return type is compatible with the expected
2567 * type according to both the inherited context and the assignment
2568 * context.
2569 */
2570 class FunctionalReturnContext extends Check.NestedCheckContext {
2572 FunctionalReturnContext(CheckContext enclosingContext) {
2573 super(enclosingContext);
2574 }
2576 @Override
2577 public boolean compatible(Type found, Type req, Warner warn) {
2578 //return type must be compatible in both current context and assignment context
2579 return chk.basicHandler.compatible(found, inferenceContext().asFree(req), warn);
2580 }
2582 @Override
2583 public void report(DiagnosticPosition pos, JCDiagnostic details) {
2584 enclosingContext.report(pos, diags.fragment("incompatible.ret.type.in.lambda", details));
2585 }
2586 }
2588 class ExpressionLambdaReturnContext extends FunctionalReturnContext {
2590 JCExpression expr;
2592 ExpressionLambdaReturnContext(JCExpression expr, CheckContext enclosingContext) {
2593 super(enclosingContext);
2594 this.expr = expr;
2595 }
2597 @Override
2598 public boolean compatible(Type found, Type req, Warner warn) {
2599 //a void return is compatible with an expression statement lambda
2600 return TreeInfo.isExpressionStatement(expr) && req.hasTag(VOID) ||
2601 super.compatible(found, req, warn);
2602 }
2603 }
2605 /**
2606 * Lambda compatibility. Check that given return types, thrown types, parameter types
2607 * are compatible with the expected functional interface descriptor. This means that:
2608 * (i) parameter types must be identical to those of the target descriptor; (ii) return
2609 * types must be compatible with the return type of the expected descriptor;
2610 * (iii) thrown types must be 'included' in the thrown types list of the expected
2611 * descriptor.
2612 */
2613 private void checkLambdaCompatible(JCLambda tree, Type descriptor, CheckContext checkContext, boolean speculativeAttr) {
2614 Type returnType = checkContext.inferenceContext().asFree(descriptor.getReturnType());
2616 //return values have already been checked - but if lambda has no return
2617 //values, we must ensure that void/value compatibility is correct;
2618 //this amounts at checking that, if a lambda body can complete normally,
2619 //the descriptor's return type must be void
2620 if (tree.getBodyKind() == JCLambda.BodyKind.STATEMENT && tree.canCompleteNormally &&
2621 !returnType.hasTag(VOID) && returnType != Type.recoveryType) {
2622 checkContext.report(tree, diags.fragment("incompatible.ret.type.in.lambda",
2623 diags.fragment("missing.ret.val", returnType)));
2624 }
2626 List<Type> argTypes = checkContext.inferenceContext().asFree(descriptor.getParameterTypes());
2627 if (!types.isSameTypes(argTypes, TreeInfo.types(tree.params))) {
2628 checkContext.report(tree, diags.fragment("incompatible.arg.types.in.lambda"));
2629 }
2631 if (!speculativeAttr) {
2632 List<Type> thrownTypes = checkContext.inferenceContext().asFree(descriptor.getThrownTypes());
2633 if (chk.unhandled(tree.inferredThrownTypes == null ? List.<Type>nil() : tree.inferredThrownTypes, thrownTypes).nonEmpty()) {
2634 log.error(tree, "incompatible.thrown.types.in.lambda", tree.inferredThrownTypes);
2635 }
2636 }
2637 }
2639 private Env<AttrContext> lambdaEnv(JCLambda that, Env<AttrContext> env) {
2640 Env<AttrContext> lambdaEnv;
2641 Symbol owner = env.info.scope.owner;
2642 if (owner.kind == VAR && owner.owner.kind == TYP) {
2643 //field initializer
2644 lambdaEnv = env.dup(that, env.info.dup(env.info.scope.dupUnshared()));
2645 lambdaEnv.info.scope.owner =
2646 new MethodSymbol((owner.flags() & STATIC) | BLOCK, names.empty, null,
2647 env.info.scope.owner);
2648 } else {
2649 lambdaEnv = env.dup(that, env.info.dup(env.info.scope.dup()));
2650 }
2651 return lambdaEnv;
2652 }
2654 @Override
2655 public void visitReference(final JCMemberReference that) {
2656 if (pt().isErroneous() || (pt().hasTag(NONE) && pt() != Type.recoveryType)) {
2657 if (pt().hasTag(NONE)) {
2658 //method reference only allowed in assignment or method invocation/cast context
2659 log.error(that.pos(), "unexpected.mref");
2660 }
2661 result = that.type = types.createErrorType(pt());
2662 return;
2663 }
2664 final Env<AttrContext> localEnv = env.dup(that);
2665 try {
2666 //attribute member reference qualifier - if this is a constructor
2667 //reference, the expected kind must be a type
2668 Type exprType = attribTree(that.expr, env, memberReferenceQualifierResult(that));
2670 if (that.getMode() == JCMemberReference.ReferenceMode.NEW) {
2671 exprType = chk.checkConstructorRefType(that.expr, exprType);
2672 }
2674 if (exprType.isErroneous()) {
2675 //if the qualifier expression contains problems,
2676 //give up attribution of method reference
2677 result = that.type = exprType;
2678 return;
2679 }
2681 if (TreeInfo.isStaticSelector(that.expr, names)) {
2682 //if the qualifier is a type, validate it; raw warning check is
2683 //omitted as we don't know at this stage as to whether this is a
2684 //raw selector (because of inference)
2685 chk.validate(that.expr, env, false);
2686 }
2688 //attrib type-arguments
2689 List<Type> typeargtypes = List.nil();
2690 if (that.typeargs != null) {
2691 typeargtypes = attribTypes(that.typeargs, localEnv);
2692 }
2694 Type target;
2695 Type desc;
2696 if (pt() != Type.recoveryType) {
2697 target = targetChecker.visit(pt(), that);
2698 desc = types.findDescriptorType(target);
2699 } else {
2700 target = Type.recoveryType;
2701 desc = fallbackDescriptorType(that);
2702 }
2704 setFunctionalInfo(localEnv, that, pt(), desc, target, resultInfo.checkContext);
2705 List<Type> argtypes = desc.getParameterTypes();
2706 Resolve.MethodCheck referenceCheck = rs.resolveMethodCheck;
2708 if (resultInfo.checkContext.inferenceContext().free(argtypes)) {
2709 referenceCheck = rs.new MethodReferenceCheck(resultInfo.checkContext.inferenceContext());
2710 }
2712 Pair<Symbol, Resolve.ReferenceLookupHelper> refResult = null;
2713 List<Type> saved_undet = resultInfo.checkContext.inferenceContext().save();
2714 try {
2715 refResult = rs.resolveMemberReference(that.pos(), localEnv, that, that.expr.type,
2716 that.name, argtypes, typeargtypes, true, referenceCheck,
2717 resultInfo.checkContext.inferenceContext());
2718 } finally {
2719 resultInfo.checkContext.inferenceContext().rollback(saved_undet);
2720 }
2722 Symbol refSym = refResult.fst;
2723 Resolve.ReferenceLookupHelper lookupHelper = refResult.snd;
2725 if (refSym.kind != MTH) {
2726 boolean targetError;
2727 switch (refSym.kind) {
2728 case ABSENT_MTH:
2729 targetError = false;
2730 break;
2731 case WRONG_MTH:
2732 case WRONG_MTHS:
2733 case AMBIGUOUS:
2734 case HIDDEN:
2735 case STATICERR:
2736 case MISSING_ENCL:
2737 targetError = true;
2738 break;
2739 default:
2740 Assert.error("unexpected result kind " + refSym.kind);
2741 targetError = false;
2742 }
2744 JCDiagnostic detailsDiag = ((Resolve.ResolveError)refSym).getDiagnostic(JCDiagnostic.DiagnosticType.FRAGMENT,
2745 that, exprType.tsym, exprType, that.name, argtypes, typeargtypes);
2747 JCDiagnostic.DiagnosticType diagKind = targetError ?
2748 JCDiagnostic.DiagnosticType.FRAGMENT : JCDiagnostic.DiagnosticType.ERROR;
2750 JCDiagnostic diag = diags.create(diagKind, log.currentSource(), that,
2751 "invalid.mref", Kinds.kindName(that.getMode()), detailsDiag);
2753 if (targetError && target == Type.recoveryType) {
2754 //a target error doesn't make sense during recovery stage
2755 //as we don't know what actual parameter types are
2756 result = that.type = target;
2757 return;
2758 } else {
2759 if (targetError) {
2760 resultInfo.checkContext.report(that, diag);
2761 } else {
2762 log.report(diag);
2763 }
2764 result = that.type = types.createErrorType(target);
2765 return;
2766 }
2767 }
2769 that.sym = refSym.baseSymbol();
2770 that.kind = lookupHelper.referenceKind(that.sym);
2771 that.ownerAccessible = rs.isAccessible(localEnv, that.sym.enclClass());
2773 if (desc.getReturnType() == Type.recoveryType) {
2774 // stop here
2775 result = that.type = target;
2776 return;
2777 }
2779 if (resultInfo.checkContext.deferredAttrContext().mode == AttrMode.CHECK) {
2781 if (that.getMode() == ReferenceMode.INVOKE &&
2782 TreeInfo.isStaticSelector(that.expr, names) &&
2783 that.kind.isUnbound() &&
2784 !desc.getParameterTypes().head.isParameterized()) {
2785 chk.checkRaw(that.expr, localEnv);
2786 }
2788 if (!that.kind.isUnbound() &&
2789 that.getMode() == ReferenceMode.INVOKE &&
2790 TreeInfo.isStaticSelector(that.expr, names) &&
2791 !that.sym.isStatic()) {
2792 log.error(that.expr.pos(), "invalid.mref", Kinds.kindName(that.getMode()),
2793 diags.fragment("non-static.cant.be.ref", Kinds.kindName(refSym), refSym));
2794 result = that.type = types.createErrorType(target);
2795 return;
2796 }
2798 if (that.kind.isUnbound() &&
2799 that.getMode() == ReferenceMode.INVOKE &&
2800 TreeInfo.isStaticSelector(that.expr, names) &&
2801 that.sym.isStatic()) {
2802 log.error(that.expr.pos(), "invalid.mref", Kinds.kindName(that.getMode()),
2803 diags.fragment("static.method.in.unbound.lookup", Kinds.kindName(refSym), refSym));
2804 result = that.type = types.createErrorType(target);
2805 return;
2806 }
2808 if (that.sym.isStatic() && TreeInfo.isStaticSelector(that.expr, names) &&
2809 exprType.getTypeArguments().nonEmpty()) {
2810 //static ref with class type-args
2811 log.error(that.expr.pos(), "invalid.mref", Kinds.kindName(that.getMode()),
2812 diags.fragment("static.mref.with.targs"));
2813 result = that.type = types.createErrorType(target);
2814 return;
2815 }
2817 if (that.sym.isStatic() && !TreeInfo.isStaticSelector(that.expr, names) &&
2818 !that.kind.isUnbound()) {
2819 //no static bound mrefs
2820 log.error(that.expr.pos(), "invalid.mref", Kinds.kindName(that.getMode()),
2821 diags.fragment("static.bound.mref"));
2822 result = that.type = types.createErrorType(target);
2823 return;
2824 }
2826 if (!refSym.isStatic() && that.kind == JCMemberReference.ReferenceKind.SUPER) {
2827 // Check that super-qualified symbols are not abstract (JLS)
2828 rs.checkNonAbstract(that.pos(), that.sym);
2829 }
2830 }
2832 ResultInfo checkInfo =
2833 resultInfo.dup(newMethodTemplate(
2834 desc.getReturnType().hasTag(VOID) ? Type.noType : desc.getReturnType(),
2835 that.kind.isUnbound() ? argtypes.tail : argtypes, typeargtypes));
2837 Type refType = checkId(that, lookupHelper.site, refSym, localEnv, checkInfo);
2839 if (that.kind.isUnbound() &&
2840 resultInfo.checkContext.inferenceContext().free(argtypes.head)) {
2841 //re-generate inference constraints for unbound receiver
2842 if (!types.isSubtype(resultInfo.checkContext.inferenceContext().asFree(argtypes.head), exprType)) {
2843 //cannot happen as this has already been checked - we just need
2844 //to regenerate the inference constraints, as that has been lost
2845 //as a result of the call to inferenceContext.save()
2846 Assert.error("Can't get here");
2847 }
2848 }
2850 if (!refType.isErroneous()) {
2851 refType = types.createMethodTypeWithReturn(refType,
2852 adjustMethodReturnType(lookupHelper.site, that.name, checkInfo.pt.getParameterTypes(), refType.getReturnType()));
2853 }
2855 //go ahead with standard method reference compatibility check - note that param check
2856 //is a no-op (as this has been taken care during method applicability)
2857 boolean isSpeculativeRound =
2858 resultInfo.checkContext.deferredAttrContext().mode == DeferredAttr.AttrMode.SPECULATIVE;
2859 checkReferenceCompatible(that, desc, refType, resultInfo.checkContext, isSpeculativeRound);
2860 if (!isSpeculativeRound) {
2861 checkAccessibleTypes(that, localEnv, resultInfo.checkContext.inferenceContext(), desc, target);
2862 }
2863 result = check(that, target, VAL, resultInfo);
2864 } catch (Types.FunctionDescriptorLookupError ex) {
2865 JCDiagnostic cause = ex.getDiagnostic();
2866 resultInfo.checkContext.report(that, cause);
2867 result = that.type = types.createErrorType(pt());
2868 return;
2869 }
2870 }
2871 //where
2872 ResultInfo memberReferenceQualifierResult(JCMemberReference tree) {
2873 //if this is a constructor reference, the expected kind must be a type
2874 return new ResultInfo(tree.getMode() == ReferenceMode.INVOKE ? VAL | TYP : TYP, Type.noType);
2875 }
2878 @SuppressWarnings("fallthrough")
2879 void checkReferenceCompatible(JCMemberReference tree, Type descriptor, Type refType, CheckContext checkContext, boolean speculativeAttr) {
2880 Type returnType = checkContext.inferenceContext().asFree(descriptor.getReturnType());
2882 Type resType;
2883 switch (tree.getMode()) {
2884 case NEW:
2885 if (!tree.expr.type.isRaw()) {
2886 resType = tree.expr.type;
2887 break;
2888 }
2889 default:
2890 resType = refType.getReturnType();
2891 }
2893 Type incompatibleReturnType = resType;
2895 if (returnType.hasTag(VOID)) {
2896 incompatibleReturnType = null;
2897 }
2899 if (!returnType.hasTag(VOID) && !resType.hasTag(VOID)) {
2900 if (resType.isErroneous() ||
2901 new FunctionalReturnContext(checkContext).compatible(resType, returnType, types.noWarnings)) {
2902 incompatibleReturnType = null;
2903 }
2904 }
2906 if (incompatibleReturnType != null) {
2907 checkContext.report(tree, diags.fragment("incompatible.ret.type.in.mref",
2908 diags.fragment("inconvertible.types", resType, descriptor.getReturnType())));
2909 }
2911 if (!speculativeAttr) {
2912 List<Type> thrownTypes = checkContext.inferenceContext().asFree(descriptor.getThrownTypes());
2913 if (chk.unhandled(refType.getThrownTypes(), thrownTypes).nonEmpty()) {
2914 log.error(tree, "incompatible.thrown.types.in.mref", refType.getThrownTypes());
2915 }
2916 }
2917 }
2919 /**
2920 * Set functional type info on the underlying AST. Note: as the target descriptor
2921 * might contain inference variables, we might need to register an hook in the
2922 * current inference context.
2923 */
2924 private void setFunctionalInfo(final Env<AttrContext> env, final JCFunctionalExpression fExpr,
2925 final Type pt, final Type descriptorType, final Type primaryTarget, final CheckContext checkContext) {
2926 if (checkContext.inferenceContext().free(descriptorType)) {
2927 checkContext.inferenceContext().addFreeTypeListener(List.of(pt, descriptorType), new FreeTypeListener() {
2928 public void typesInferred(InferenceContext inferenceContext) {
2929 setFunctionalInfo(env, fExpr, pt, inferenceContext.asInstType(descriptorType),
2930 inferenceContext.asInstType(primaryTarget), checkContext);
2931 }
2932 });
2933 } else {
2934 ListBuffer<Type> targets = ListBuffer.lb();
2935 if (pt.hasTag(CLASS)) {
2936 if (pt.isCompound()) {
2937 targets.append(types.removeWildcards(primaryTarget)); //this goes first
2938 for (Type t : ((IntersectionClassType)pt()).interfaces_field) {
2939 if (t != primaryTarget) {
2940 targets.append(types.removeWildcards(t));
2941 }
2942 }
2943 } else {
2944 targets.append(types.removeWildcards(primaryTarget));
2945 }
2946 }
2947 fExpr.targets = targets.toList();
2948 if (checkContext.deferredAttrContext().mode == DeferredAttr.AttrMode.CHECK &&
2949 pt != Type.recoveryType) {
2950 //check that functional interface class is well-formed
2951 ClassSymbol csym = types.makeFunctionalInterfaceClass(env,
2952 names.empty, List.of(fExpr.targets.head), ABSTRACT);
2953 if (csym != null) {
2954 chk.checkImplementations(env.tree, csym, csym);
2955 }
2956 }
2957 }
2958 }
2960 public void visitParens(JCParens tree) {
2961 Type owntype = attribTree(tree.expr, env, resultInfo);
2962 result = check(tree, owntype, pkind(), resultInfo);
2963 Symbol sym = TreeInfo.symbol(tree);
2964 if (sym != null && (sym.kind&(TYP|PCK)) != 0)
2965 log.error(tree.pos(), "illegal.start.of.type");
2966 }
2968 public void visitAssign(JCAssign tree) {
2969 Type owntype = attribTree(tree.lhs, env.dup(tree), varInfo);
2970 Type capturedType = capture(owntype);
2971 attribExpr(tree.rhs, env, owntype);
2972 result = check(tree, capturedType, VAL, resultInfo);
2973 }
2975 public void visitAssignop(JCAssignOp tree) {
2976 // Attribute arguments.
2977 Type owntype = attribTree(tree.lhs, env, varInfo);
2978 Type operand = attribExpr(tree.rhs, env);
2979 // Find operator.
2980 Symbol operator = tree.operator = rs.resolveBinaryOperator(
2981 tree.pos(), tree.getTag().noAssignOp(), env,
2982 owntype, operand);
2984 if (operator.kind == MTH &&
2985 !owntype.isErroneous() &&
2986 !operand.isErroneous()) {
2987 chk.checkOperator(tree.pos(),
2988 (OperatorSymbol)operator,
2989 tree.getTag().noAssignOp(),
2990 owntype,
2991 operand);
2992 chk.checkDivZero(tree.rhs.pos(), operator, operand);
2993 chk.checkCastable(tree.rhs.pos(),
2994 operator.type.getReturnType(),
2995 owntype);
2996 }
2997 result = check(tree, owntype, VAL, resultInfo);
2998 }
3000 public void visitUnary(JCUnary tree) {
3001 // Attribute arguments.
3002 Type argtype = (tree.getTag().isIncOrDecUnaryOp())
3003 ? attribTree(tree.arg, env, varInfo)
3004 : chk.checkNonVoid(tree.arg.pos(), attribExpr(tree.arg, env));
3006 // Find operator.
3007 Symbol operator = tree.operator =
3008 rs.resolveUnaryOperator(tree.pos(), tree.getTag(), env, argtype);
3010 Type owntype = types.createErrorType(tree.type);
3011 if (operator.kind == MTH &&
3012 !argtype.isErroneous()) {
3013 owntype = (tree.getTag().isIncOrDecUnaryOp())
3014 ? tree.arg.type
3015 : operator.type.getReturnType();
3016 int opc = ((OperatorSymbol)operator).opcode;
3018 // If the argument is constant, fold it.
3019 if (argtype.constValue() != null) {
3020 Type ctype = cfolder.fold1(opc, argtype);
3021 if (ctype != null) {
3022 owntype = cfolder.coerce(ctype, owntype);
3024 // Remove constant types from arguments to
3025 // conserve space. The parser will fold concatenations
3026 // of string literals; the code here also
3027 // gets rid of intermediate results when some of the
3028 // operands are constant identifiers.
3029 if (tree.arg.type.tsym == syms.stringType.tsym) {
3030 tree.arg.type = syms.stringType;
3031 }
3032 }
3033 }
3034 }
3035 result = check(tree, owntype, VAL, resultInfo);
3036 }
3038 public void visitBinary(JCBinary tree) {
3039 // Attribute arguments.
3040 Type left = chk.checkNonVoid(tree.lhs.pos(), attribExpr(tree.lhs, env));
3041 Type right = chk.checkNonVoid(tree.lhs.pos(), attribExpr(tree.rhs, env));
3043 // Find operator.
3044 Symbol operator = tree.operator =
3045 rs.resolveBinaryOperator(tree.pos(), tree.getTag(), env, left, right);
3047 Type owntype = types.createErrorType(tree.type);
3048 if (operator.kind == MTH &&
3049 !left.isErroneous() &&
3050 !right.isErroneous()) {
3051 owntype = operator.type.getReturnType();
3052 // This will figure out when unboxing can happen and
3053 // choose the right comparison operator.
3054 int opc = chk.checkOperator(tree.lhs.pos(),
3055 (OperatorSymbol)operator,
3056 tree.getTag(),
3057 left,
3058 right);
3060 // If both arguments are constants, fold them.
3061 if (left.constValue() != null && right.constValue() != null) {
3062 Type ctype = cfolder.fold2(opc, left, right);
3063 if (ctype != null) {
3064 owntype = cfolder.coerce(ctype, owntype);
3066 // Remove constant types from arguments to
3067 // conserve space. The parser will fold concatenations
3068 // of string literals; the code here also
3069 // gets rid of intermediate results when some of the
3070 // operands are constant identifiers.
3071 if (tree.lhs.type.tsym == syms.stringType.tsym) {
3072 tree.lhs.type = syms.stringType;
3073 }
3074 if (tree.rhs.type.tsym == syms.stringType.tsym) {
3075 tree.rhs.type = syms.stringType;
3076 }
3077 }
3078 }
3080 // Check that argument types of a reference ==, != are
3081 // castable to each other, (JLS 15.21). Note: unboxing
3082 // comparisons will not have an acmp* opc at this point.
3083 if ((opc == ByteCodes.if_acmpeq || opc == ByteCodes.if_acmpne)) {
3084 if (!types.isEqualityComparable(left, right,
3085 new Warner(tree.pos()))) {
3086 log.error(tree.pos(), "incomparable.types", left, right);
3087 }
3088 }
3090 chk.checkDivZero(tree.rhs.pos(), operator, right);
3091 }
3092 result = check(tree, owntype, VAL, resultInfo);
3093 }
3095 public void visitTypeCast(final JCTypeCast tree) {
3096 Type clazztype = attribType(tree.clazz, env);
3097 chk.validate(tree.clazz, env, false);
3098 //a fresh environment is required for 292 inference to work properly ---
3099 //see Infer.instantiatePolymorphicSignatureInstance()
3100 Env<AttrContext> localEnv = env.dup(tree);
3101 //should we propagate the target type?
3102 final ResultInfo castInfo;
3103 JCExpression expr = TreeInfo.skipParens(tree.expr);
3104 boolean isPoly = allowPoly && (expr.hasTag(LAMBDA) || expr.hasTag(REFERENCE));
3105 if (isPoly) {
3106 //expression is a poly - we need to propagate target type info
3107 castInfo = new ResultInfo(VAL, clazztype, new Check.NestedCheckContext(resultInfo.checkContext) {
3108 @Override
3109 public boolean compatible(Type found, Type req, Warner warn) {
3110 return types.isCastable(found, req, warn);
3111 }
3112 });
3113 } else {
3114 //standalone cast - target-type info is not propagated
3115 castInfo = unknownExprInfo;
3116 }
3117 Type exprtype = attribTree(tree.expr, localEnv, castInfo);
3118 Type owntype = isPoly ? clazztype : chk.checkCastable(tree.expr.pos(), exprtype, clazztype);
3119 if (exprtype.constValue() != null)
3120 owntype = cfolder.coerce(exprtype, owntype);
3121 result = check(tree, capture(owntype), VAL, resultInfo);
3122 if (!isPoly)
3123 chk.checkRedundantCast(localEnv, tree);
3124 }
3126 public void visitTypeTest(JCInstanceOf tree) {
3127 Type exprtype = chk.checkNullOrRefType(
3128 tree.expr.pos(), attribExpr(tree.expr, env));
3129 Type clazztype = chk.checkReifiableReferenceType(
3130 tree.clazz.pos(), attribType(tree.clazz, env));
3131 chk.validate(tree.clazz, env, false);
3132 chk.checkCastable(tree.expr.pos(), exprtype, clazztype);
3133 result = check(tree, syms.booleanType, VAL, resultInfo);
3134 }
3136 public void visitIndexed(JCArrayAccess tree) {
3137 Type owntype = types.createErrorType(tree.type);
3138 Type atype = attribExpr(tree.indexed, env);
3139 attribExpr(tree.index, env, syms.intType);
3140 if (types.isArray(atype))
3141 owntype = types.elemtype(atype);
3142 else if (!atype.hasTag(ERROR))
3143 log.error(tree.pos(), "array.req.but.found", atype);
3144 if ((pkind() & VAR) == 0) owntype = capture(owntype);
3145 result = check(tree, owntype, VAR, resultInfo);
3146 }
3148 public void visitIdent(JCIdent tree) {
3149 Symbol sym;
3151 // Find symbol
3152 if (pt().hasTag(METHOD) || pt().hasTag(FORALL)) {
3153 // If we are looking for a method, the prototype `pt' will be a
3154 // method type with the type of the call's arguments as parameters.
3155 env.info.pendingResolutionPhase = null;
3156 sym = rs.resolveMethod(tree.pos(), env, tree.name, pt().getParameterTypes(), pt().getTypeArguments());
3157 } else if (tree.sym != null && tree.sym.kind != VAR) {
3158 sym = tree.sym;
3159 } else {
3160 sym = rs.resolveIdent(tree.pos(), env, tree.name, pkind());
3161 }
3162 tree.sym = sym;
3164 // (1) Also find the environment current for the class where
3165 // sym is defined (`symEnv').
3166 // Only for pre-tiger versions (1.4 and earlier):
3167 // (2) Also determine whether we access symbol out of an anonymous
3168 // class in a this or super call. This is illegal for instance
3169 // members since such classes don't carry a this$n link.
3170 // (`noOuterThisPath').
3171 Env<AttrContext> symEnv = env;
3172 boolean noOuterThisPath = false;
3173 if (env.enclClass.sym.owner.kind != PCK && // we are in an inner class
3174 (sym.kind & (VAR | MTH | TYP)) != 0 &&
3175 sym.owner.kind == TYP &&
3176 tree.name != names._this && tree.name != names._super) {
3178 // Find environment in which identifier is defined.
3179 while (symEnv.outer != null &&
3180 !sym.isMemberOf(symEnv.enclClass.sym, types)) {
3181 if ((symEnv.enclClass.sym.flags() & NOOUTERTHIS) != 0)
3182 noOuterThisPath = !allowAnonOuterThis;
3183 symEnv = symEnv.outer;
3184 }
3185 }
3187 // If symbol is a variable, ...
3188 if (sym.kind == VAR) {
3189 VarSymbol v = (VarSymbol)sym;
3191 // ..., evaluate its initializer, if it has one, and check for
3192 // illegal forward reference.
3193 checkInit(tree, env, v, false);
3195 // If we are expecting a variable (as opposed to a value), check
3196 // that the variable is assignable in the current environment.
3197 if (pkind() == VAR)
3198 checkAssignable(tree.pos(), v, null, env);
3199 }
3201 // In a constructor body,
3202 // if symbol is a field or instance method, check that it is
3203 // not accessed before the supertype constructor is called.
3204 if ((symEnv.info.isSelfCall || noOuterThisPath) &&
3205 (sym.kind & (VAR | MTH)) != 0 &&
3206 sym.owner.kind == TYP &&
3207 (sym.flags() & STATIC) == 0) {
3208 chk.earlyRefError(tree.pos(), sym.kind == VAR ? sym : thisSym(tree.pos(), env));
3209 }
3210 Env<AttrContext> env1 = env;
3211 if (sym.kind != ERR && sym.kind != TYP && sym.owner != null && sym.owner != env1.enclClass.sym) {
3212 // If the found symbol is inaccessible, then it is
3213 // accessed through an enclosing instance. Locate this
3214 // enclosing instance:
3215 while (env1.outer != null && !rs.isAccessible(env, env1.enclClass.sym.type, sym))
3216 env1 = env1.outer;
3217 }
3218 result = checkId(tree, env1.enclClass.sym.type, sym, env, resultInfo);
3219 }
3221 public void visitSelect(JCFieldAccess tree) {
3222 // Determine the expected kind of the qualifier expression.
3223 int skind = 0;
3224 if (tree.name == names._this || tree.name == names._super ||
3225 tree.name == names._class)
3226 {
3227 skind = TYP;
3228 } else {
3229 if ((pkind() & PCK) != 0) skind = skind | PCK;
3230 if ((pkind() & TYP) != 0) skind = skind | TYP | PCK;
3231 if ((pkind() & (VAL | MTH)) != 0) skind = skind | VAL | TYP;
3232 }
3234 // Attribute the qualifier expression, and determine its symbol (if any).
3235 Type site = attribTree(tree.selected, env, new ResultInfo(skind, Infer.anyPoly));
3236 if ((pkind() & (PCK | TYP)) == 0)
3237 site = capture(site); // Capture field access
3239 // don't allow T.class T[].class, etc
3240 if (skind == TYP) {
3241 Type elt = site;
3242 while (elt.hasTag(ARRAY))
3243 elt = ((ArrayType)elt.unannotatedType()).elemtype;
3244 if (elt.hasTag(TYPEVAR)) {
3245 log.error(tree.pos(), "type.var.cant.be.deref");
3246 result = types.createErrorType(tree.type);
3247 return;
3248 }
3249 }
3251 // If qualifier symbol is a type or `super', assert `selectSuper'
3252 // for the selection. This is relevant for determining whether
3253 // protected symbols are accessible.
3254 Symbol sitesym = TreeInfo.symbol(tree.selected);
3255 boolean selectSuperPrev = env.info.selectSuper;
3256 env.info.selectSuper =
3257 sitesym != null &&
3258 sitesym.name == names._super;
3260 // Determine the symbol represented by the selection.
3261 env.info.pendingResolutionPhase = null;
3262 Symbol sym = selectSym(tree, sitesym, site, env, resultInfo);
3263 if (sym.exists() && !isType(sym) && (pkind() & (PCK | TYP)) != 0) {
3264 site = capture(site);
3265 sym = selectSym(tree, sitesym, site, env, resultInfo);
3266 }
3267 boolean varArgs = env.info.lastResolveVarargs();
3268 tree.sym = sym;
3270 if (site.hasTag(TYPEVAR) && !isType(sym) && sym.kind != ERR) {
3271 while (site.hasTag(TYPEVAR)) site = site.getUpperBound();
3272 site = capture(site);
3273 }
3275 // If that symbol is a variable, ...
3276 if (sym.kind == VAR) {
3277 VarSymbol v = (VarSymbol)sym;
3279 // ..., evaluate its initializer, if it has one, and check for
3280 // illegal forward reference.
3281 checkInit(tree, env, v, true);
3283 // If we are expecting a variable (as opposed to a value), check
3284 // that the variable is assignable in the current environment.
3285 if (pkind() == VAR)
3286 checkAssignable(tree.pos(), v, tree.selected, env);
3287 }
3289 if (sitesym != null &&
3290 sitesym.kind == VAR &&
3291 ((VarSymbol)sitesym).isResourceVariable() &&
3292 sym.kind == MTH &&
3293 sym.name.equals(names.close) &&
3294 sym.overrides(syms.autoCloseableClose, sitesym.type.tsym, types, true) &&
3295 env.info.lint.isEnabled(LintCategory.TRY)) {
3296 log.warning(LintCategory.TRY, tree, "try.explicit.close.call");
3297 }
3299 // Disallow selecting a type from an expression
3300 if (isType(sym) && (sitesym==null || (sitesym.kind&(TYP|PCK)) == 0)) {
3301 tree.type = check(tree.selected, pt(),
3302 sitesym == null ? VAL : sitesym.kind, new ResultInfo(TYP|PCK, pt()));
3303 }
3305 if (isType(sitesym)) {
3306 if (sym.name == names._this) {
3307 // If `C' is the currently compiled class, check that
3308 // C.this' does not appear in a call to a super(...)
3309 if (env.info.isSelfCall &&
3310 site.tsym == env.enclClass.sym) {
3311 chk.earlyRefError(tree.pos(), sym);
3312 }
3313 } else {
3314 // Check if type-qualified fields or methods are static (JLS)
3315 if ((sym.flags() & STATIC) == 0 &&
3316 !env.next.tree.hasTag(REFERENCE) &&
3317 sym.name != names._super &&
3318 (sym.kind == VAR || sym.kind == MTH)) {
3319 rs.accessBase(rs.new StaticError(sym),
3320 tree.pos(), site, sym.name, true);
3321 }
3322 }
3323 } else if (sym.kind != ERR && (sym.flags() & STATIC) != 0 && sym.name != names._class) {
3324 // If the qualified item is not a type and the selected item is static, report
3325 // a warning. Make allowance for the class of an array type e.g. Object[].class)
3326 chk.warnStatic(tree, "static.not.qualified.by.type", Kinds.kindName(sym.kind), sym.owner);
3327 }
3329 // If we are selecting an instance member via a `super', ...
3330 if (env.info.selectSuper && (sym.flags() & STATIC) == 0) {
3332 // Check that super-qualified symbols are not abstract (JLS)
3333 rs.checkNonAbstract(tree.pos(), sym);
3335 if (site.isRaw()) {
3336 // Determine argument types for site.
3337 Type site1 = types.asSuper(env.enclClass.sym.type, site.tsym);
3338 if (site1 != null) site = site1;
3339 }
3340 }
3342 env.info.selectSuper = selectSuperPrev;
3343 result = checkId(tree, site, sym, env, resultInfo);
3344 }
3345 //where
3346 /** Determine symbol referenced by a Select expression,
3347 *
3348 * @param tree The select tree.
3349 * @param site The type of the selected expression,
3350 * @param env The current environment.
3351 * @param resultInfo The current result.
3352 */
3353 private Symbol selectSym(JCFieldAccess tree,
3354 Symbol location,
3355 Type site,
3356 Env<AttrContext> env,
3357 ResultInfo resultInfo) {
3358 DiagnosticPosition pos = tree.pos();
3359 Name name = tree.name;
3360 switch (site.getTag()) {
3361 case PACKAGE:
3362 return rs.accessBase(
3363 rs.findIdentInPackage(env, site.tsym, name, resultInfo.pkind),
3364 pos, location, site, name, true);
3365 case ARRAY:
3366 case CLASS:
3367 if (resultInfo.pt.hasTag(METHOD) || resultInfo.pt.hasTag(FORALL)) {
3368 return rs.resolveQualifiedMethod(
3369 pos, env, location, site, name, resultInfo.pt.getParameterTypes(), resultInfo.pt.getTypeArguments());
3370 } else if (name == names._this || name == names._super) {
3371 return rs.resolveSelf(pos, env, site.tsym, name);
3372 } else if (name == names._class) {
3373 // In this case, we have already made sure in
3374 // visitSelect that qualifier expression is a type.
3375 Type t = syms.classType;
3376 List<Type> typeargs = allowGenerics
3377 ? List.of(types.erasure(site))
3378 : List.<Type>nil();
3379 t = new ClassType(t.getEnclosingType(), typeargs, t.tsym);
3380 return new VarSymbol(
3381 STATIC | PUBLIC | FINAL, names._class, t, site.tsym);
3382 } else {
3383 // We are seeing a plain identifier as selector.
3384 Symbol sym = rs.findIdentInType(env, site, name, resultInfo.pkind);
3385 if ((resultInfo.pkind & ERRONEOUS) == 0)
3386 sym = rs.accessBase(sym, pos, location, site, name, true);
3387 return sym;
3388 }
3389 case WILDCARD:
3390 throw new AssertionError(tree);
3391 case TYPEVAR:
3392 // Normally, site.getUpperBound() shouldn't be null.
3393 // It should only happen during memberEnter/attribBase
3394 // when determining the super type which *must* beac
3395 // done before attributing the type variables. In
3396 // other words, we are seeing this illegal program:
3397 // class B<T> extends A<T.foo> {}
3398 Symbol sym = (site.getUpperBound() != null)
3399 ? selectSym(tree, location, capture(site.getUpperBound()), env, resultInfo)
3400 : null;
3401 if (sym == null) {
3402 log.error(pos, "type.var.cant.be.deref");
3403 return syms.errSymbol;
3404 } else {
3405 Symbol sym2 = (sym.flags() & Flags.PRIVATE) != 0 ?
3406 rs.new AccessError(env, site, sym) :
3407 sym;
3408 rs.accessBase(sym2, pos, location, site, name, true);
3409 return sym;
3410 }
3411 case ERROR:
3412 // preserve identifier names through errors
3413 return types.createErrorType(name, site.tsym, site).tsym;
3414 default:
3415 // The qualifier expression is of a primitive type -- only
3416 // .class is allowed for these.
3417 if (name == names._class) {
3418 // In this case, we have already made sure in Select that
3419 // qualifier expression is a type.
3420 Type t = syms.classType;
3421 Type arg = types.boxedClass(site).type;
3422 t = new ClassType(t.getEnclosingType(), List.of(arg), t.tsym);
3423 return new VarSymbol(
3424 STATIC | PUBLIC | FINAL, names._class, t, site.tsym);
3425 } else {
3426 log.error(pos, "cant.deref", site);
3427 return syms.errSymbol;
3428 }
3429 }
3430 }
3432 /** Determine type of identifier or select expression and check that
3433 * (1) the referenced symbol is not deprecated
3434 * (2) the symbol's type is safe (@see checkSafe)
3435 * (3) if symbol is a variable, check that its type and kind are
3436 * compatible with the prototype and protokind.
3437 * (4) if symbol is an instance field of a raw type,
3438 * which is being assigned to, issue an unchecked warning if its
3439 * type changes under erasure.
3440 * (5) if symbol is an instance method of a raw type, issue an
3441 * unchecked warning if its argument types change under erasure.
3442 * If checks succeed:
3443 * If symbol is a constant, return its constant type
3444 * else if symbol is a method, return its result type
3445 * otherwise return its type.
3446 * Otherwise return errType.
3447 *
3448 * @param tree The syntax tree representing the identifier
3449 * @param site If this is a select, the type of the selected
3450 * expression, otherwise the type of the current class.
3451 * @param sym The symbol representing the identifier.
3452 * @param env The current environment.
3453 * @param resultInfo The expected result
3454 */
3455 Type checkId(JCTree tree,
3456 Type site,
3457 Symbol sym,
3458 Env<AttrContext> env,
3459 ResultInfo resultInfo) {
3460 return (resultInfo.pt.hasTag(FORALL) || resultInfo.pt.hasTag(METHOD)) ?
3461 checkMethodId(tree, site, sym, env, resultInfo) :
3462 checkIdInternal(tree, site, sym, resultInfo.pt, env, resultInfo);
3463 }
3465 Type checkMethodId(JCTree tree,
3466 Type site,
3467 Symbol sym,
3468 Env<AttrContext> env,
3469 ResultInfo resultInfo) {
3470 boolean isPolymorhicSignature =
3471 (sym.baseSymbol().flags() & SIGNATURE_POLYMORPHIC) != 0;
3472 return isPolymorhicSignature ?
3473 checkSigPolyMethodId(tree, site, sym, env, resultInfo) :
3474 checkMethodIdInternal(tree, site, sym, env, resultInfo);
3475 }
3477 Type checkSigPolyMethodId(JCTree tree,
3478 Type site,
3479 Symbol sym,
3480 Env<AttrContext> env,
3481 ResultInfo resultInfo) {
3482 //recover original symbol for signature polymorphic methods
3483 checkMethodIdInternal(tree, site, sym.baseSymbol(), env, resultInfo);
3484 env.info.pendingResolutionPhase = Resolve.MethodResolutionPhase.BASIC;
3485 return sym.type;
3486 }
3488 Type checkMethodIdInternal(JCTree tree,
3489 Type site,
3490 Symbol sym,
3491 Env<AttrContext> env,
3492 ResultInfo resultInfo) {
3493 if ((resultInfo.pkind & POLY) != 0) {
3494 Type pt = resultInfo.pt.map(deferredAttr.new RecoveryDeferredTypeMap(AttrMode.SPECULATIVE, sym, env.info.pendingResolutionPhase));
3495 Type owntype = checkIdInternal(tree, site, sym, pt, env, resultInfo);
3496 resultInfo.pt.map(deferredAttr.new RecoveryDeferredTypeMap(AttrMode.CHECK, sym, env.info.pendingResolutionPhase));
3497 return owntype;
3498 } else {
3499 return checkIdInternal(tree, site, sym, resultInfo.pt, env, resultInfo);
3500 }
3501 }
3503 Type checkIdInternal(JCTree tree,
3504 Type site,
3505 Symbol sym,
3506 Type pt,
3507 Env<AttrContext> env,
3508 ResultInfo resultInfo) {
3509 if (pt.isErroneous()) {
3510 return types.createErrorType(site);
3511 }
3512 Type owntype; // The computed type of this identifier occurrence.
3513 switch (sym.kind) {
3514 case TYP:
3515 // For types, the computed type equals the symbol's type,
3516 // except for two situations:
3517 owntype = sym.type;
3518 if (owntype.hasTag(CLASS)) {
3519 chk.checkForBadAuxiliaryClassAccess(tree.pos(), env, (ClassSymbol)sym);
3520 Type ownOuter = owntype.getEnclosingType();
3522 // (a) If the symbol's type is parameterized, erase it
3523 // because no type parameters were given.
3524 // We recover generic outer type later in visitTypeApply.
3525 if (owntype.tsym.type.getTypeArguments().nonEmpty()) {
3526 owntype = types.erasure(owntype);
3527 }
3529 // (b) If the symbol's type is an inner class, then
3530 // we have to interpret its outer type as a superclass
3531 // of the site type. Example:
3532 //
3533 // class Tree<A> { class Visitor { ... } }
3534 // class PointTree extends Tree<Point> { ... }
3535 // ...PointTree.Visitor...
3536 //
3537 // Then the type of the last expression above is
3538 // Tree<Point>.Visitor.
3539 else if (ownOuter.hasTag(CLASS) && site != ownOuter) {
3540 Type normOuter = site;
3541 if (normOuter.hasTag(CLASS)) {
3542 normOuter = types.asEnclosingSuper(site, ownOuter.tsym);
3543 if (site.isAnnotated()) {
3544 // Propagate any type annotations.
3545 // TODO: should asEnclosingSuper do this?
3546 // Note that the type annotations in site will be updated
3547 // by annotateType. Therefore, modify site instead
3548 // of creating a new AnnotatedType.
3549 ((AnnotatedType)site).underlyingType = normOuter;
3550 normOuter = site;
3551 }
3552 }
3553 if (normOuter == null) // perhaps from an import
3554 normOuter = types.erasure(ownOuter);
3555 if (normOuter != ownOuter)
3556 owntype = new ClassType(
3557 normOuter, List.<Type>nil(), owntype.tsym);
3558 }
3559 }
3560 break;
3561 case VAR:
3562 VarSymbol v = (VarSymbol)sym;
3563 // Test (4): if symbol is an instance field of a raw type,
3564 // which is being assigned to, issue an unchecked warning if
3565 // its type changes under erasure.
3566 if (allowGenerics &&
3567 resultInfo.pkind == VAR &&
3568 v.owner.kind == TYP &&
3569 (v.flags() & STATIC) == 0 &&
3570 (site.hasTag(CLASS) || site.hasTag(TYPEVAR))) {
3571 Type s = types.asOuterSuper(site, v.owner);
3572 if (s != null &&
3573 s.isRaw() &&
3574 !types.isSameType(v.type, v.erasure(types))) {
3575 chk.warnUnchecked(tree.pos(),
3576 "unchecked.assign.to.var",
3577 v, s);
3578 }
3579 }
3580 // The computed type of a variable is the type of the
3581 // variable symbol, taken as a member of the site type.
3582 owntype = (sym.owner.kind == TYP &&
3583 sym.name != names._this && sym.name != names._super)
3584 ? types.memberType(site, sym)
3585 : sym.type;
3587 // If the variable is a constant, record constant value in
3588 // computed type.
3589 if (v.getConstValue() != null && isStaticReference(tree))
3590 owntype = owntype.constType(v.getConstValue());
3592 if (resultInfo.pkind == VAL) {
3593 owntype = capture(owntype); // capture "names as expressions"
3594 }
3595 break;
3596 case MTH: {
3597 owntype = checkMethod(site, sym,
3598 new ResultInfo(resultInfo.pkind, resultInfo.pt.getReturnType(), resultInfo.checkContext),
3599 env, TreeInfo.args(env.tree), resultInfo.pt.getParameterTypes(),
3600 resultInfo.pt.getTypeArguments());
3601 break;
3602 }
3603 case PCK: case ERR:
3604 owntype = sym.type;
3605 break;
3606 default:
3607 throw new AssertionError("unexpected kind: " + sym.kind +
3608 " in tree " + tree);
3609 }
3611 // Test (1): emit a `deprecation' warning if symbol is deprecated.
3612 // (for constructors, the error was given when the constructor was
3613 // resolved)
3615 if (sym.name != names.init) {
3616 chk.checkDeprecated(tree.pos(), env.info.scope.owner, sym);
3617 chk.checkSunAPI(tree.pos(), sym);
3618 chk.checkProfile(tree.pos(), sym);
3619 }
3621 // Test (3): if symbol is a variable, check that its type and
3622 // kind are compatible with the prototype and protokind.
3623 return check(tree, owntype, sym.kind, resultInfo);
3624 }
3626 /** Check that variable is initialized and evaluate the variable's
3627 * initializer, if not yet done. Also check that variable is not
3628 * referenced before it is defined.
3629 * @param tree The tree making up the variable reference.
3630 * @param env The current environment.
3631 * @param v The variable's symbol.
3632 */
3633 private void checkInit(JCTree tree,
3634 Env<AttrContext> env,
3635 VarSymbol v,
3636 boolean onlyWarning) {
3637 // System.err.println(v + " " + ((v.flags() & STATIC) != 0) + " " +
3638 // tree.pos + " " + v.pos + " " +
3639 // Resolve.isStatic(env));//DEBUG
3641 // A forward reference is diagnosed if the declaration position
3642 // of the variable is greater than the current tree position
3643 // and the tree and variable definition occur in the same class
3644 // definition. Note that writes don't count as references.
3645 // This check applies only to class and instance
3646 // variables. Local variables follow different scope rules,
3647 // and are subject to definite assignment checking.
3648 if ((env.info.enclVar == v || v.pos > tree.pos) &&
3649 v.owner.kind == TYP &&
3650 canOwnInitializer(owner(env)) &&
3651 v.owner == env.info.scope.owner.enclClass() &&
3652 ((v.flags() & STATIC) != 0) == Resolve.isStatic(env) &&
3653 (!env.tree.hasTag(ASSIGN) ||
3654 TreeInfo.skipParens(((JCAssign) env.tree).lhs) != tree)) {
3655 String suffix = (env.info.enclVar == v) ?
3656 "self.ref" : "forward.ref";
3657 if (!onlyWarning || isStaticEnumField(v)) {
3658 log.error(tree.pos(), "illegal." + suffix);
3659 } else if (useBeforeDeclarationWarning) {
3660 log.warning(tree.pos(), suffix, v);
3661 }
3662 }
3664 v.getConstValue(); // ensure initializer is evaluated
3666 checkEnumInitializer(tree, env, v);
3667 }
3669 /**
3670 * Check for illegal references to static members of enum. In
3671 * an enum type, constructors and initializers may not
3672 * reference its static members unless they are constant.
3673 *
3674 * @param tree The tree making up the variable reference.
3675 * @param env The current environment.
3676 * @param v The variable's symbol.
3677 * @jls section 8.9 Enums
3678 */
3679 private void checkEnumInitializer(JCTree tree, Env<AttrContext> env, VarSymbol v) {
3680 // JLS:
3681 //
3682 // "It is a compile-time error to reference a static field
3683 // of an enum type that is not a compile-time constant
3684 // (15.28) from constructors, instance initializer blocks,
3685 // or instance variable initializer expressions of that
3686 // type. It is a compile-time error for the constructors,
3687 // instance initializer blocks, or instance variable
3688 // initializer expressions of an enum constant e to refer
3689 // to itself or to an enum constant of the same type that
3690 // is declared to the right of e."
3691 if (isStaticEnumField(v)) {
3692 ClassSymbol enclClass = env.info.scope.owner.enclClass();
3694 if (enclClass == null || enclClass.owner == null)
3695 return;
3697 // See if the enclosing class is the enum (or a
3698 // subclass thereof) declaring v. If not, this
3699 // reference is OK.
3700 if (v.owner != enclClass && !types.isSubtype(enclClass.type, v.owner.type))
3701 return;
3703 // If the reference isn't from an initializer, then
3704 // the reference is OK.
3705 if (!Resolve.isInitializer(env))
3706 return;
3708 log.error(tree.pos(), "illegal.enum.static.ref");
3709 }
3710 }
3712 /** Is the given symbol a static, non-constant field of an Enum?
3713 * Note: enum literals should not be regarded as such
3714 */
3715 private boolean isStaticEnumField(VarSymbol v) {
3716 return Flags.isEnum(v.owner) &&
3717 Flags.isStatic(v) &&
3718 !Flags.isConstant(v) &&
3719 v.name != names._class;
3720 }
3722 /** Can the given symbol be the owner of code which forms part
3723 * if class initialization? This is the case if the symbol is
3724 * a type or field, or if the symbol is the synthetic method.
3725 * owning a block.
3726 */
3727 private boolean canOwnInitializer(Symbol sym) {
3728 return
3729 (sym.kind & (VAR | TYP)) != 0 ||
3730 (sym.kind == MTH && (sym.flags() & BLOCK) != 0);
3731 }
3733 Warner noteWarner = new Warner();
3735 /**
3736 * Check that method arguments conform to its instantiation.
3737 **/
3738 public Type checkMethod(Type site,
3739 Symbol sym,
3740 ResultInfo resultInfo,
3741 Env<AttrContext> env,
3742 final List<JCExpression> argtrees,
3743 List<Type> argtypes,
3744 List<Type> typeargtypes) {
3745 // Test (5): if symbol is an instance method of a raw type, issue
3746 // an unchecked warning if its argument types change under erasure.
3747 if (allowGenerics &&
3748 (sym.flags() & STATIC) == 0 &&
3749 (site.hasTag(CLASS) || site.hasTag(TYPEVAR))) {
3750 Type s = types.asOuterSuper(site, sym.owner);
3751 if (s != null && s.isRaw() &&
3752 !types.isSameTypes(sym.type.getParameterTypes(),
3753 sym.erasure(types).getParameterTypes())) {
3754 chk.warnUnchecked(env.tree.pos(),
3755 "unchecked.call.mbr.of.raw.type",
3756 sym, s);
3757 }
3758 }
3760 if (env.info.defaultSuperCallSite != null) {
3761 for (Type sup : types.interfaces(env.enclClass.type).prepend(types.supertype((env.enclClass.type)))) {
3762 if (!sup.tsym.isSubClass(sym.enclClass(), types) ||
3763 types.isSameType(sup, env.info.defaultSuperCallSite)) continue;
3764 List<MethodSymbol> icand_sup =
3765 types.interfaceCandidates(sup, (MethodSymbol)sym);
3766 if (icand_sup.nonEmpty() &&
3767 icand_sup.head != sym &&
3768 icand_sup.head.overrides(sym, icand_sup.head.enclClass(), types, true)) {
3769 log.error(env.tree.pos(), "illegal.default.super.call", env.info.defaultSuperCallSite,
3770 diags.fragment("overridden.default", sym, sup));
3771 break;
3772 }
3773 }
3774 env.info.defaultSuperCallSite = null;
3775 }
3777 if (sym.isStatic() && site.isInterface() && env.tree.hasTag(APPLY)) {
3778 JCMethodInvocation app = (JCMethodInvocation)env.tree;
3779 if (app.meth.hasTag(SELECT) &&
3780 !TreeInfo.isStaticSelector(((JCFieldAccess)app.meth).selected, names)) {
3781 log.error(env.tree.pos(), "illegal.static.intf.meth.call", site);
3782 }
3783 }
3785 // Compute the identifier's instantiated type.
3786 // For methods, we need to compute the instance type by
3787 // Resolve.instantiate from the symbol's type as well as
3788 // any type arguments and value arguments.
3789 noteWarner.clear();
3790 try {
3791 Type owntype = rs.checkMethod(
3792 env,
3793 site,
3794 sym,
3795 resultInfo,
3796 argtypes,
3797 typeargtypes,
3798 noteWarner);
3800 DeferredAttr.DeferredTypeMap checkDeferredMap =
3801 deferredAttr.new DeferredTypeMap(DeferredAttr.AttrMode.CHECK, sym, env.info.pendingResolutionPhase);
3803 argtypes = Type.map(argtypes, checkDeferredMap);
3805 if (noteWarner.hasNonSilentLint(LintCategory.UNCHECKED)) {
3806 chk.warnUnchecked(env.tree.pos(),
3807 "unchecked.meth.invocation.applied",
3808 kindName(sym),
3809 sym.name,
3810 rs.methodArguments(sym.type.getParameterTypes()),
3811 rs.methodArguments(Type.map(argtypes, checkDeferredMap)),
3812 kindName(sym.location()),
3813 sym.location());
3814 owntype = new MethodType(owntype.getParameterTypes(),
3815 types.erasure(owntype.getReturnType()),
3816 types.erasure(owntype.getThrownTypes()),
3817 syms.methodClass);
3818 }
3820 return chk.checkMethod(owntype, sym, env, argtrees, argtypes, env.info.lastResolveVarargs(),
3821 resultInfo.checkContext.inferenceContext());
3822 } catch (Infer.InferenceException ex) {
3823 //invalid target type - propagate exception outwards or report error
3824 //depending on the current check context
3825 resultInfo.checkContext.report(env.tree.pos(), ex.getDiagnostic());
3826 return types.createErrorType(site);
3827 } catch (Resolve.InapplicableMethodException ex) {
3828 Assert.error(ex.getDiagnostic().getMessage(Locale.getDefault()));
3829 return null;
3830 }
3831 }
3833 public void visitLiteral(JCLiteral tree) {
3834 result = check(
3835 tree, litType(tree.typetag).constType(tree.value), VAL, resultInfo);
3836 }
3837 //where
3838 /** Return the type of a literal with given type tag.
3839 */
3840 Type litType(TypeTag tag) {
3841 return (tag == CLASS) ? syms.stringType : syms.typeOfTag[tag.ordinal()];
3842 }
3844 public void visitTypeIdent(JCPrimitiveTypeTree tree) {
3845 result = check(tree, syms.typeOfTag[tree.typetag.ordinal()], TYP, resultInfo);
3846 }
3848 public void visitTypeArray(JCArrayTypeTree tree) {
3849 Type etype = attribType(tree.elemtype, env);
3850 Type type = new ArrayType(etype, syms.arrayClass);
3851 result = check(tree, type, TYP, resultInfo);
3852 }
3854 /** Visitor method for parameterized types.
3855 * Bound checking is left until later, since types are attributed
3856 * before supertype structure is completely known
3857 */
3858 public void visitTypeApply(JCTypeApply tree) {
3859 Type owntype = types.createErrorType(tree.type);
3861 // Attribute functor part of application and make sure it's a class.
3862 Type clazztype = chk.checkClassType(tree.clazz.pos(), attribType(tree.clazz, env));
3864 // Attribute type parameters
3865 List<Type> actuals = attribTypes(tree.arguments, env);
3867 if (clazztype.hasTag(CLASS)) {
3868 List<Type> formals = clazztype.tsym.type.getTypeArguments();
3869 if (actuals.isEmpty()) //diamond
3870 actuals = formals;
3872 if (actuals.length() == formals.length()) {
3873 List<Type> a = actuals;
3874 List<Type> f = formals;
3875 while (a.nonEmpty()) {
3876 a.head = a.head.withTypeVar(f.head);
3877 a = a.tail;
3878 f = f.tail;
3879 }
3880 // Compute the proper generic outer
3881 Type clazzOuter = clazztype.getEnclosingType();
3882 if (clazzOuter.hasTag(CLASS)) {
3883 Type site;
3884 JCExpression clazz = TreeInfo.typeIn(tree.clazz);
3885 if (clazz.hasTag(IDENT)) {
3886 site = env.enclClass.sym.type;
3887 } else if (clazz.hasTag(SELECT)) {
3888 site = ((JCFieldAccess) clazz).selected.type;
3889 } else throw new AssertionError(""+tree);
3890 if (clazzOuter.hasTag(CLASS) && site != clazzOuter) {
3891 if (site.hasTag(CLASS))
3892 site = types.asOuterSuper(site, clazzOuter.tsym);
3893 if (site == null)
3894 site = types.erasure(clazzOuter);
3895 clazzOuter = site;
3896 }
3897 }
3898 owntype = new ClassType(clazzOuter, actuals, clazztype.tsym);
3899 if (clazztype.isAnnotated()) {
3900 // Use the same AnnotatedType, because it will have
3901 // its annotations set later.
3902 ((AnnotatedType)clazztype).underlyingType = owntype;
3903 owntype = clazztype;
3904 }
3905 } else {
3906 if (formals.length() != 0) {
3907 log.error(tree.pos(), "wrong.number.type.args",
3908 Integer.toString(formals.length()));
3909 } else {
3910 log.error(tree.pos(), "type.doesnt.take.params", clazztype.tsym);
3911 }
3912 owntype = types.createErrorType(tree.type);
3913 }
3914 }
3915 result = check(tree, owntype, TYP, resultInfo);
3916 }
3918 public void visitTypeUnion(JCTypeUnion tree) {
3919 ListBuffer<Type> multicatchTypes = ListBuffer.lb();
3920 ListBuffer<Type> all_multicatchTypes = null; // lazy, only if needed
3921 for (JCExpression typeTree : tree.alternatives) {
3922 Type ctype = attribType(typeTree, env);
3923 ctype = chk.checkType(typeTree.pos(),
3924 chk.checkClassType(typeTree.pos(), ctype),
3925 syms.throwableType);
3926 if (!ctype.isErroneous()) {
3927 //check that alternatives of a union type are pairwise
3928 //unrelated w.r.t. subtyping
3929 if (chk.intersects(ctype, multicatchTypes.toList())) {
3930 for (Type t : multicatchTypes) {
3931 boolean sub = types.isSubtype(ctype, t);
3932 boolean sup = types.isSubtype(t, ctype);
3933 if (sub || sup) {
3934 //assume 'a' <: 'b'
3935 Type a = sub ? ctype : t;
3936 Type b = sub ? t : ctype;
3937 log.error(typeTree.pos(), "multicatch.types.must.be.disjoint", a, b);
3938 }
3939 }
3940 }
3941 multicatchTypes.append(ctype);
3942 if (all_multicatchTypes != null)
3943 all_multicatchTypes.append(ctype);
3944 } else {
3945 if (all_multicatchTypes == null) {
3946 all_multicatchTypes = ListBuffer.lb();
3947 all_multicatchTypes.appendList(multicatchTypes);
3948 }
3949 all_multicatchTypes.append(ctype);
3950 }
3951 }
3952 Type t = check(tree, types.lub(multicatchTypes.toList()), TYP, resultInfo);
3953 if (t.hasTag(CLASS)) {
3954 List<Type> alternatives =
3955 ((all_multicatchTypes == null) ? multicatchTypes : all_multicatchTypes).toList();
3956 t = new UnionClassType((ClassType) t, alternatives);
3957 }
3958 tree.type = result = t;
3959 }
3961 public void visitTypeIntersection(JCTypeIntersection tree) {
3962 attribTypes(tree.bounds, env);
3963 tree.type = result = checkIntersection(tree, tree.bounds);
3964 }
3966 public void visitTypeParameter(JCTypeParameter tree) {
3967 TypeVar typeVar = (TypeVar) tree.type;
3969 if (tree.annotations != null && tree.annotations.nonEmpty()) {
3970 AnnotatedType antype = new AnnotatedType(typeVar);
3971 annotateType(antype, tree.annotations);
3972 tree.type = antype;
3973 }
3975 if (!typeVar.bound.isErroneous()) {
3976 //fixup type-parameter bound computed in 'attribTypeVariables'
3977 typeVar.bound = checkIntersection(tree, tree.bounds);
3978 }
3979 }
3981 Type checkIntersection(JCTree tree, List<JCExpression> bounds) {
3982 Set<Type> boundSet = new HashSet<Type>();
3983 if (bounds.nonEmpty()) {
3984 // accept class or interface or typevar as first bound.
3985 bounds.head.type = checkBase(bounds.head.type, bounds.head, env, false, false, false);
3986 boundSet.add(types.erasure(bounds.head.type));
3987 if (bounds.head.type.isErroneous()) {
3988 return bounds.head.type;
3989 }
3990 else if (bounds.head.type.hasTag(TYPEVAR)) {
3991 // if first bound was a typevar, do not accept further bounds.
3992 if (bounds.tail.nonEmpty()) {
3993 log.error(bounds.tail.head.pos(),
3994 "type.var.may.not.be.followed.by.other.bounds");
3995 return bounds.head.type;
3996 }
3997 } else {
3998 // if first bound was a class or interface, accept only interfaces
3999 // as further bounds.
4000 for (JCExpression bound : bounds.tail) {
4001 bound.type = checkBase(bound.type, bound, env, false, true, false);
4002 if (bound.type.isErroneous()) {
4003 bounds = List.of(bound);
4004 }
4005 else if (bound.type.hasTag(CLASS)) {
4006 chk.checkNotRepeated(bound.pos(), types.erasure(bound.type), boundSet);
4007 }
4008 }
4009 }
4010 }
4012 if (bounds.length() == 0) {
4013 return syms.objectType;
4014 } else if (bounds.length() == 1) {
4015 return bounds.head.type;
4016 } else {
4017 Type owntype = types.makeCompoundType(TreeInfo.types(bounds));
4018 if (tree.hasTag(TYPEINTERSECTION)) {
4019 ((IntersectionClassType)owntype).intersectionKind =
4020 IntersectionClassType.IntersectionKind.EXPLICIT;
4021 }
4022 // ... the variable's bound is a class type flagged COMPOUND
4023 // (see comment for TypeVar.bound).
4024 // In this case, generate a class tree that represents the
4025 // bound class, ...
4026 JCExpression extending;
4027 List<JCExpression> implementing;
4028 if (!bounds.head.type.isInterface()) {
4029 extending = bounds.head;
4030 implementing = bounds.tail;
4031 } else {
4032 extending = null;
4033 implementing = bounds;
4034 }
4035 JCClassDecl cd = make.at(tree).ClassDef(
4036 make.Modifiers(PUBLIC | ABSTRACT),
4037 names.empty, List.<JCTypeParameter>nil(),
4038 extending, implementing, List.<JCTree>nil());
4040 ClassSymbol c = (ClassSymbol)owntype.tsym;
4041 Assert.check((c.flags() & COMPOUND) != 0);
4042 cd.sym = c;
4043 c.sourcefile = env.toplevel.sourcefile;
4045 // ... and attribute the bound class
4046 c.flags_field |= UNATTRIBUTED;
4047 Env<AttrContext> cenv = enter.classEnv(cd, env);
4048 enter.typeEnvs.put(c, cenv);
4049 attribClass(c);
4050 return owntype;
4051 }
4052 }
4054 public void visitWildcard(JCWildcard tree) {
4055 //- System.err.println("visitWildcard("+tree+");");//DEBUG
4056 Type type = (tree.kind.kind == BoundKind.UNBOUND)
4057 ? syms.objectType
4058 : attribType(tree.inner, env);
4059 result = check(tree, new WildcardType(chk.checkRefType(tree.pos(), type),
4060 tree.kind.kind,
4061 syms.boundClass),
4062 TYP, resultInfo);
4063 }
4065 public void visitAnnotation(JCAnnotation tree) {
4066 log.error(tree.pos(), "annotation.not.valid.for.type", pt());
4067 result = tree.type = syms.errType;
4068 }
4070 public void visitAnnotatedType(JCAnnotatedType tree) {
4071 Type underlyingType = attribType(tree.getUnderlyingType(), env);
4072 this.attribAnnotationTypes(tree.annotations, env);
4073 AnnotatedType antype = new AnnotatedType(underlyingType);
4074 annotateType(antype, tree.annotations);
4075 result = tree.type = antype;
4076 }
4078 /**
4079 * Apply the annotations to the particular type.
4080 */
4081 public void annotateType(final AnnotatedType type, final List<JCAnnotation> annotations) {
4082 if (annotations.isEmpty())
4083 return;
4084 annotate.typeAnnotation(new Annotate.Annotator() {
4085 @Override
4086 public String toString() {
4087 return "annotate " + annotations + " onto " + type;
4088 }
4089 @Override
4090 public void enterAnnotation() {
4091 List<Attribute.TypeCompound> compounds = fromAnnotations(annotations);
4092 type.typeAnnotations = compounds;
4093 }
4094 });
4095 }
4097 private static List<Attribute.TypeCompound> fromAnnotations(List<JCAnnotation> annotations) {
4098 if (annotations.isEmpty())
4099 return List.nil();
4101 ListBuffer<Attribute.TypeCompound> buf = ListBuffer.lb();
4102 for (JCAnnotation anno : annotations) {
4103 if (anno.attribute != null) {
4104 // TODO: this null-check is only needed for an obscure
4105 // ordering issue, where annotate.flush is called when
4106 // the attribute is not set yet. For an example failure
4107 // try the referenceinfos/NestedTypes.java test.
4108 // Any better solutions?
4109 buf.append((Attribute.TypeCompound) anno.attribute);
4110 }
4111 }
4112 return buf.toList();
4113 }
4115 public void visitErroneous(JCErroneous tree) {
4116 if (tree.errs != null)
4117 for (JCTree err : tree.errs)
4118 attribTree(err, env, new ResultInfo(ERR, pt()));
4119 result = tree.type = syms.errType;
4120 }
4122 /** Default visitor method for all other trees.
4123 */
4124 public void visitTree(JCTree tree) {
4125 throw new AssertionError();
4126 }
4128 /**
4129 * Attribute an env for either a top level tree or class declaration.
4130 */
4131 public void attrib(Env<AttrContext> env) {
4132 if (env.tree.hasTag(TOPLEVEL))
4133 attribTopLevel(env);
4134 else
4135 attribClass(env.tree.pos(), env.enclClass.sym);
4136 }
4138 /**
4139 * Attribute a top level tree. These trees are encountered when the
4140 * package declaration has annotations.
4141 */
4142 public void attribTopLevel(Env<AttrContext> env) {
4143 JCCompilationUnit toplevel = env.toplevel;
4144 try {
4145 annotate.flush();
4146 chk.validateAnnotations(toplevel.packageAnnotations, toplevel.packge);
4147 } catch (CompletionFailure ex) {
4148 chk.completionError(toplevel.pos(), ex);
4149 }
4150 }
4152 /** Main method: attribute class definition associated with given class symbol.
4153 * reporting completion failures at the given position.
4154 * @param pos The source position at which completion errors are to be
4155 * reported.
4156 * @param c The class symbol whose definition will be attributed.
4157 */
4158 public void attribClass(DiagnosticPosition pos, ClassSymbol c) {
4159 try {
4160 annotate.flush();
4161 attribClass(c);
4162 } catch (CompletionFailure ex) {
4163 chk.completionError(pos, ex);
4164 }
4165 }
4167 /** Attribute class definition associated with given class symbol.
4168 * @param c The class symbol whose definition will be attributed.
4169 */
4170 void attribClass(ClassSymbol c) throws CompletionFailure {
4171 if (c.type.hasTag(ERROR)) return;
4173 // Check for cycles in the inheritance graph, which can arise from
4174 // ill-formed class files.
4175 chk.checkNonCyclic(null, c.type);
4177 Type st = types.supertype(c.type);
4178 if ((c.flags_field & Flags.COMPOUND) == 0) {
4179 // First, attribute superclass.
4180 if (st.hasTag(CLASS))
4181 attribClass((ClassSymbol)st.tsym);
4183 // Next attribute owner, if it is a class.
4184 if (c.owner.kind == TYP && c.owner.type.hasTag(CLASS))
4185 attribClass((ClassSymbol)c.owner);
4186 }
4188 // The previous operations might have attributed the current class
4189 // if there was a cycle. So we test first whether the class is still
4190 // UNATTRIBUTED.
4191 if ((c.flags_field & UNATTRIBUTED) != 0) {
4192 c.flags_field &= ~UNATTRIBUTED;
4194 // Get environment current at the point of class definition.
4195 Env<AttrContext> env = enter.typeEnvs.get(c);
4197 // The info.lint field in the envs stored in enter.typeEnvs is deliberately uninitialized,
4198 // because the annotations were not available at the time the env was created. Therefore,
4199 // we look up the environment chain for the first enclosing environment for which the
4200 // lint value is set. Typically, this is the parent env, but might be further if there
4201 // are any envs created as a result of TypeParameter nodes.
4202 Env<AttrContext> lintEnv = env;
4203 while (lintEnv.info.lint == null)
4204 lintEnv = lintEnv.next;
4206 // Having found the enclosing lint value, we can initialize the lint value for this class
4207 env.info.lint = lintEnv.info.lint.augment(c);
4209 Lint prevLint = chk.setLint(env.info.lint);
4210 JavaFileObject prev = log.useSource(c.sourcefile);
4211 ResultInfo prevReturnRes = env.info.returnResult;
4213 try {
4214 env.info.returnResult = null;
4215 // java.lang.Enum may not be subclassed by a non-enum
4216 if (st.tsym == syms.enumSym &&
4217 ((c.flags_field & (Flags.ENUM|Flags.COMPOUND)) == 0))
4218 log.error(env.tree.pos(), "enum.no.subclassing");
4220 // Enums may not be extended by source-level classes
4221 if (st.tsym != null &&
4222 ((st.tsym.flags_field & Flags.ENUM) != 0) &&
4223 ((c.flags_field & (Flags.ENUM | Flags.COMPOUND)) == 0)) {
4224 log.error(env.tree.pos(), "enum.types.not.extensible");
4225 }
4226 attribClassBody(env, c);
4228 chk.checkDeprecatedAnnotation(env.tree.pos(), c);
4229 chk.checkClassOverrideEqualsAndHashIfNeeded(env.tree.pos(), c);
4230 } finally {
4231 env.info.returnResult = prevReturnRes;
4232 log.useSource(prev);
4233 chk.setLint(prevLint);
4234 }
4236 }
4237 }
4239 public void visitImport(JCImport tree) {
4240 // nothing to do
4241 }
4243 /** Finish the attribution of a class. */
4244 private void attribClassBody(Env<AttrContext> env, ClassSymbol c) {
4245 JCClassDecl tree = (JCClassDecl)env.tree;
4246 Assert.check(c == tree.sym);
4248 // Validate annotations
4249 chk.validateAnnotations(tree.mods.annotations, c);
4251 // Validate type parameters, supertype and interfaces.
4252 attribStats(tree.typarams, env);
4253 if (!c.isAnonymous()) {
4254 //already checked if anonymous
4255 chk.validate(tree.typarams, env);
4256 chk.validate(tree.extending, env);
4257 chk.validate(tree.implementing, env);
4258 }
4260 // If this is a non-abstract class, check that it has no abstract
4261 // methods or unimplemented methods of an implemented interface.
4262 if ((c.flags() & (ABSTRACT | INTERFACE)) == 0) {
4263 if (!relax)
4264 chk.checkAllDefined(tree.pos(), c);
4265 }
4267 if ((c.flags() & ANNOTATION) != 0) {
4268 if (tree.implementing.nonEmpty())
4269 log.error(tree.implementing.head.pos(),
4270 "cant.extend.intf.annotation");
4271 if (tree.typarams.nonEmpty())
4272 log.error(tree.typarams.head.pos(),
4273 "intf.annotation.cant.have.type.params");
4275 // If this annotation has a @Repeatable, validate
4276 Attribute.Compound repeatable = c.attribute(syms.repeatableType.tsym);
4277 if (repeatable != null) {
4278 // get diagnostic position for error reporting
4279 DiagnosticPosition cbPos = getDiagnosticPosition(tree, repeatable.type);
4280 Assert.checkNonNull(cbPos);
4282 chk.validateRepeatable(c, repeatable, cbPos);
4283 }
4284 } else {
4285 // Check that all extended classes and interfaces
4286 // are compatible (i.e. no two define methods with same arguments
4287 // yet different return types). (JLS 8.4.6.3)
4288 chk.checkCompatibleSupertypes(tree.pos(), c.type);
4289 if (allowDefaultMethods) {
4290 chk.checkDefaultMethodClashes(tree.pos(), c.type);
4291 }
4292 }
4294 // Check that class does not import the same parameterized interface
4295 // with two different argument lists.
4296 chk.checkClassBounds(tree.pos(), c.type);
4298 tree.type = c.type;
4300 for (List<JCTypeParameter> l = tree.typarams;
4301 l.nonEmpty(); l = l.tail) {
4302 Assert.checkNonNull(env.info.scope.lookup(l.head.name).scope);
4303 }
4305 // Check that a generic class doesn't extend Throwable
4306 if (!c.type.allparams().isEmpty() && types.isSubtype(c.type, syms.throwableType))
4307 log.error(tree.extending.pos(), "generic.throwable");
4309 // Check that all methods which implement some
4310 // method conform to the method they implement.
4311 chk.checkImplementations(tree);
4313 //check that a resource implementing AutoCloseable cannot throw InterruptedException
4314 checkAutoCloseable(tree.pos(), env, c.type);
4316 for (List<JCTree> l = tree.defs; l.nonEmpty(); l = l.tail) {
4317 // Attribute declaration
4318 attribStat(l.head, env);
4319 // Check that declarations in inner classes are not static (JLS 8.1.2)
4320 // Make an exception for static constants.
4321 if (c.owner.kind != PCK &&
4322 ((c.flags() & STATIC) == 0 || c.name == names.empty) &&
4323 (TreeInfo.flags(l.head) & (STATIC | INTERFACE)) != 0) {
4324 Symbol sym = null;
4325 if (l.head.hasTag(VARDEF)) sym = ((JCVariableDecl) l.head).sym;
4326 if (sym == null ||
4327 sym.kind != VAR ||
4328 ((VarSymbol) sym).getConstValue() == null)
4329 log.error(l.head.pos(), "icls.cant.have.static.decl", c);
4330 }
4331 }
4333 // Check for cycles among non-initial constructors.
4334 chk.checkCyclicConstructors(tree);
4336 // Check for cycles among annotation elements.
4337 chk.checkNonCyclicElements(tree);
4339 // Check for proper use of serialVersionUID
4340 if (env.info.lint.isEnabled(LintCategory.SERIAL) &&
4341 isSerializable(c) &&
4342 (c.flags() & Flags.ENUM) == 0 &&
4343 checkForSerial(c)) {
4344 checkSerialVersionUID(tree, c);
4345 }
4346 if (allowTypeAnnos) {
4347 // Correctly organize the postions of the type annotations
4348 TypeAnnotations.organizeTypeAnnotationsBodies(this.syms, this.names, this.log, tree);
4350 // Check type annotations applicability rules
4351 validateTypeAnnotations(tree);
4352 }
4353 }
4354 // where
4355 boolean checkForSerial(ClassSymbol c) {
4356 if ((c.flags() & ABSTRACT) == 0) {
4357 return true;
4358 } else {
4359 return c.members().anyMatch(anyNonAbstractOrDefaultMethod);
4360 }
4361 }
4363 public static final Filter<Symbol> anyNonAbstractOrDefaultMethod = new Filter<Symbol>() {
4364 @Override
4365 public boolean accepts(Symbol s) {
4366 return s.kind == Kinds.MTH &&
4367 (s.flags() & (DEFAULT | ABSTRACT)) != ABSTRACT;
4368 }
4369 };
4371 /** get a diagnostic position for an attribute of Type t, or null if attribute missing */
4372 private DiagnosticPosition getDiagnosticPosition(JCClassDecl tree, Type t) {
4373 for(List<JCAnnotation> al = tree.mods.annotations; !al.isEmpty(); al = al.tail) {
4374 if (types.isSameType(al.head.annotationType.type, t))
4375 return al.head.pos();
4376 }
4378 return null;
4379 }
4381 /** check if a class is a subtype of Serializable, if that is available. */
4382 private boolean isSerializable(ClassSymbol c) {
4383 try {
4384 syms.serializableType.complete();
4385 }
4386 catch (CompletionFailure e) {
4387 return false;
4388 }
4389 return types.isSubtype(c.type, syms.serializableType);
4390 }
4392 /** Check that an appropriate serialVersionUID member is defined. */
4393 private void checkSerialVersionUID(JCClassDecl tree, ClassSymbol c) {
4395 // check for presence of serialVersionUID
4396 Scope.Entry e = c.members().lookup(names.serialVersionUID);
4397 while (e.scope != null && e.sym.kind != VAR) e = e.next();
4398 if (e.scope == null) {
4399 log.warning(LintCategory.SERIAL,
4400 tree.pos(), "missing.SVUID", c);
4401 return;
4402 }
4404 // check that it is static final
4405 VarSymbol svuid = (VarSymbol)e.sym;
4406 if ((svuid.flags() & (STATIC | FINAL)) !=
4407 (STATIC | FINAL))
4408 log.warning(LintCategory.SERIAL,
4409 TreeInfo.diagnosticPositionFor(svuid, tree), "improper.SVUID", c);
4411 // check that it is long
4412 else if (!svuid.type.hasTag(LONG))
4413 log.warning(LintCategory.SERIAL,
4414 TreeInfo.diagnosticPositionFor(svuid, tree), "long.SVUID", c);
4416 // check constant
4417 else if (svuid.getConstValue() == null)
4418 log.warning(LintCategory.SERIAL,
4419 TreeInfo.diagnosticPositionFor(svuid, tree), "constant.SVUID", c);
4420 }
4422 private Type capture(Type type) {
4423 return types.capture(type);
4424 }
4426 private void validateTypeAnnotations(JCTree tree) {
4427 tree.accept(typeAnnotationsValidator);
4428 }
4429 //where
4430 private final JCTree.Visitor typeAnnotationsValidator = new TreeScanner() {
4432 private boolean checkAllAnnotations = false;
4434 public void visitAnnotation(JCAnnotation tree) {
4435 if (tree.hasTag(TYPE_ANNOTATION) || checkAllAnnotations) {
4436 chk.validateTypeAnnotation(tree, false);
4437 }
4438 super.visitAnnotation(tree);
4439 }
4440 public void visitTypeParameter(JCTypeParameter tree) {
4441 chk.validateTypeAnnotations(tree.annotations, true);
4442 scan(tree.bounds);
4443 // Don't call super.
4444 // This is needed because above we call validateTypeAnnotation with
4445 // false, which would forbid annotations on type parameters.
4446 // super.visitTypeParameter(tree);
4447 }
4448 public void visitMethodDef(JCMethodDecl tree) {
4449 if (tree.recvparam != null &&
4450 tree.recvparam.vartype.type.getKind() != TypeKind.ERROR) {
4451 checkForDeclarationAnnotations(tree.recvparam.mods.annotations,
4452 tree.recvparam.vartype.type.tsym);
4453 }
4454 if (tree.restype != null && tree.restype.type != null) {
4455 validateAnnotatedType(tree.restype, tree.restype.type);
4456 }
4457 super.visitMethodDef(tree);
4458 }
4459 public void visitVarDef(final JCVariableDecl tree) {
4460 if (tree.sym != null && tree.sym.type != null)
4461 validateAnnotatedType(tree, tree.sym.type);
4462 super.visitVarDef(tree);
4463 }
4464 public void visitTypeCast(JCTypeCast tree) {
4465 if (tree.clazz != null && tree.clazz.type != null)
4466 validateAnnotatedType(tree.clazz, tree.clazz.type);
4467 super.visitTypeCast(tree);
4468 }
4469 public void visitTypeTest(JCInstanceOf tree) {
4470 if (tree.clazz != null && tree.clazz.type != null)
4471 validateAnnotatedType(tree.clazz, tree.clazz.type);
4472 super.visitTypeTest(tree);
4473 }
4474 public void visitNewClass(JCNewClass tree) {
4475 if (tree.clazz.hasTag(ANNOTATED_TYPE)) {
4476 boolean prevCheck = this.checkAllAnnotations;
4477 try {
4478 this.checkAllAnnotations = true;
4479 scan(((JCAnnotatedType)tree.clazz).annotations);
4480 } finally {
4481 this.checkAllAnnotations = prevCheck;
4482 }
4483 }
4484 super.visitNewClass(tree);
4485 }
4486 public void visitNewArray(JCNewArray tree) {
4487 if (tree.elemtype != null && tree.elemtype.hasTag(ANNOTATED_TYPE)) {
4488 boolean prevCheck = this.checkAllAnnotations;
4489 try {
4490 this.checkAllAnnotations = true;
4491 scan(((JCAnnotatedType)tree.elemtype).annotations);
4492 } finally {
4493 this.checkAllAnnotations = prevCheck;
4494 }
4495 }
4496 super.visitNewArray(tree);
4497 }
4499 /* I would want to model this after
4500 * com.sun.tools.javac.comp.Check.Validator.visitSelectInternal(JCFieldAccess)
4501 * and override visitSelect and visitTypeApply.
4502 * However, we only set the annotated type in the top-level type
4503 * of the symbol.
4504 * Therefore, we need to override each individual location where a type
4505 * can occur.
4506 */
4507 private void validateAnnotatedType(final JCTree errtree, final Type type) {
4508 if (type.getEnclosingType() != null &&
4509 type != type.getEnclosingType()) {
4510 validateEnclosingAnnotatedType(errtree, type.getEnclosingType());
4511 }
4512 for (Type targ : type.getTypeArguments()) {
4513 validateAnnotatedType(errtree, targ);
4514 }
4515 }
4516 private void validateEnclosingAnnotatedType(final JCTree errtree, final Type type) {
4517 validateAnnotatedType(errtree, type);
4518 if (type.tsym != null &&
4519 type.tsym.isStatic() &&
4520 type.getAnnotationMirrors().nonEmpty()) {
4521 // Enclosing static classes cannot have type annotations.
4522 log.error(errtree.pos(), "cant.annotate.static.class");
4523 }
4524 }
4525 };
4527 // <editor-fold desc="post-attribution visitor">
4529 /**
4530 * Handle missing types/symbols in an AST. This routine is useful when
4531 * the compiler has encountered some errors (which might have ended up
4532 * terminating attribution abruptly); if the compiler is used in fail-over
4533 * mode (e.g. by an IDE) and the AST contains semantic errors, this routine
4534 * prevents NPE to be progagated during subsequent compilation steps.
4535 */
4536 public void postAttr(JCTree tree) {
4537 new PostAttrAnalyzer().scan(tree);
4538 }
4540 class PostAttrAnalyzer extends TreeScanner {
4542 private void initTypeIfNeeded(JCTree that) {
4543 if (that.type == null) {
4544 that.type = syms.unknownType;
4545 }
4546 }
4548 @Override
4549 public void scan(JCTree tree) {
4550 if (tree == null) return;
4551 if (tree instanceof JCExpression) {
4552 initTypeIfNeeded(tree);
4553 }
4554 super.scan(tree);
4555 }
4557 @Override
4558 public void visitIdent(JCIdent that) {
4559 if (that.sym == null) {
4560 that.sym = syms.unknownSymbol;
4561 }
4562 }
4564 @Override
4565 public void visitSelect(JCFieldAccess that) {
4566 if (that.sym == null) {
4567 that.sym = syms.unknownSymbol;
4568 }
4569 super.visitSelect(that);
4570 }
4572 @Override
4573 public void visitClassDef(JCClassDecl that) {
4574 initTypeIfNeeded(that);
4575 if (that.sym == null) {
4576 that.sym = new ClassSymbol(0, that.name, that.type, syms.noSymbol);
4577 }
4578 super.visitClassDef(that);
4579 }
4581 @Override
4582 public void visitMethodDef(JCMethodDecl that) {
4583 initTypeIfNeeded(that);
4584 if (that.sym == null) {
4585 that.sym = new MethodSymbol(0, that.name, that.type, syms.noSymbol);
4586 }
4587 super.visitMethodDef(that);
4588 }
4590 @Override
4591 public void visitVarDef(JCVariableDecl that) {
4592 initTypeIfNeeded(that);
4593 if (that.sym == null) {
4594 that.sym = new VarSymbol(0, that.name, that.type, syms.noSymbol);
4595 that.sym.adr = 0;
4596 }
4597 super.visitVarDef(that);
4598 }
4600 @Override
4601 public void visitNewClass(JCNewClass that) {
4602 if (that.constructor == null) {
4603 that.constructor = new MethodSymbol(0, names.init, syms.unknownType, syms.noSymbol);
4604 }
4605 if (that.constructorType == null) {
4606 that.constructorType = syms.unknownType;
4607 }
4608 super.visitNewClass(that);
4609 }
4611 @Override
4612 public void visitAssignop(JCAssignOp that) {
4613 if (that.operator == null)
4614 that.operator = new OperatorSymbol(names.empty, syms.unknownType, -1, syms.noSymbol);
4615 super.visitAssignop(that);
4616 }
4618 @Override
4619 public void visitBinary(JCBinary that) {
4620 if (that.operator == null)
4621 that.operator = new OperatorSymbol(names.empty, syms.unknownType, -1, syms.noSymbol);
4622 super.visitBinary(that);
4623 }
4625 @Override
4626 public void visitUnary(JCUnary that) {
4627 if (that.operator == null)
4628 that.operator = new OperatorSymbol(names.empty, syms.unknownType, -1, syms.noSymbol);
4629 super.visitUnary(that);
4630 }
4632 @Override
4633 public void visitLambda(JCLambda that) {
4634 super.visitLambda(that);
4635 if (that.targets == null) {
4636 that.targets = List.nil();
4637 }
4638 }
4640 @Override
4641 public void visitReference(JCMemberReference that) {
4642 super.visitReference(that);
4643 if (that.sym == null) {
4644 that.sym = new MethodSymbol(0, names.empty, syms.unknownType, syms.noSymbol);
4645 }
4646 if (that.targets == null) {
4647 that.targets = List.nil();
4648 }
4649 }
4650 }
4651 // </editor-fold>
4652 }