Tue, 22 Oct 2013 13:54:49 +0100
8025290: javac implicit versus explicit lambda compilation error
Reviewed-by: jjg, dlsmith
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.code.TypeTag.ARRAY;
62 import static com.sun.tools.javac.tree.JCTree.Tag.*;
64 /** This is the main context-dependent analysis phase in GJC. It
65 * encompasses name resolution, type checking and constant folding as
66 * subtasks. Some subtasks involve auxiliary classes.
67 * @see Check
68 * @see Resolve
69 * @see ConstFold
70 * @see Infer
71 *
72 * <p><b>This is NOT part of any supported API.
73 * If you write code that depends on this, you do so at your own risk.
74 * This code and its internal interfaces are subject to change or
75 * deletion without notice.</b>
76 */
77 public class Attr extends JCTree.Visitor {
78 protected static final Context.Key<Attr> attrKey =
79 new Context.Key<Attr>();
81 final Names names;
82 final Log log;
83 final Symtab syms;
84 final Resolve rs;
85 final Infer infer;
86 final DeferredAttr deferredAttr;
87 final Check chk;
88 final Flow flow;
89 final MemberEnter memberEnter;
90 final TreeMaker make;
91 final ConstFold cfolder;
92 final Enter enter;
93 final Target target;
94 final Types types;
95 final JCDiagnostic.Factory diags;
96 final Annotate annotate;
97 final TypeAnnotations typeAnnotations;
98 final DeferredLintHandler deferredLintHandler;
100 public static Attr instance(Context context) {
101 Attr instance = context.get(attrKey);
102 if (instance == null)
103 instance = new Attr(context);
104 return instance;
105 }
107 protected Attr(Context context) {
108 context.put(attrKey, this);
110 names = Names.instance(context);
111 log = Log.instance(context);
112 syms = Symtab.instance(context);
113 rs = Resolve.instance(context);
114 chk = Check.instance(context);
115 flow = Flow.instance(context);
116 memberEnter = MemberEnter.instance(context);
117 make = TreeMaker.instance(context);
118 enter = Enter.instance(context);
119 infer = Infer.instance(context);
120 deferredAttr = DeferredAttr.instance(context);
121 cfolder = ConstFold.instance(context);
122 target = Target.instance(context);
123 types = Types.instance(context);
124 diags = JCDiagnostic.Factory.instance(context);
125 annotate = Annotate.instance(context);
126 typeAnnotations = TypeAnnotations.instance(context);
127 deferredLintHandler = DeferredLintHandler.instance(context);
129 Options options = Options.instance(context);
131 Source source = Source.instance(context);
132 allowGenerics = source.allowGenerics();
133 allowVarargs = source.allowVarargs();
134 allowEnums = source.allowEnums();
135 allowBoxing = source.allowBoxing();
136 allowCovariantReturns = source.allowCovariantReturns();
137 allowAnonOuterThis = source.allowAnonOuterThis();
138 allowStringsInSwitch = source.allowStringsInSwitch();
139 allowPoly = source.allowPoly();
140 allowTypeAnnos = source.allowTypeAnnotations();
141 allowLambda = source.allowLambda();
142 allowDefaultMethods = source.allowDefaultMethods();
143 sourceName = source.name;
144 relax = (options.isSet("-retrofit") ||
145 options.isSet("-relax"));
146 findDiamonds = options.get("findDiamond") != null &&
147 source.allowDiamond();
148 useBeforeDeclarationWarning = options.isSet("useBeforeDeclarationWarning");
149 identifyLambdaCandidate = options.getBoolean("identifyLambdaCandidate", false);
151 statInfo = new ResultInfo(NIL, Type.noType);
152 varInfo = new ResultInfo(VAR, Type.noType);
153 unknownExprInfo = new ResultInfo(VAL, Type.noType);
154 unknownAnyPolyInfo = new ResultInfo(VAL, Infer.anyPoly);
155 unknownTypeInfo = new ResultInfo(TYP, Type.noType);
156 unknownTypeExprInfo = new ResultInfo(Kinds.TYP | Kinds.VAL, Type.noType);
157 recoveryInfo = new RecoveryInfo(deferredAttr.emptyDeferredAttrContext);
158 }
160 /** Switch: relax some constraints for retrofit mode.
161 */
162 boolean relax;
164 /** Switch: support target-typing inference
165 */
166 boolean allowPoly;
168 /** Switch: support type annotations.
169 */
170 boolean allowTypeAnnos;
172 /** Switch: support generics?
173 */
174 boolean allowGenerics;
176 /** Switch: allow variable-arity methods.
177 */
178 boolean allowVarargs;
180 /** Switch: support enums?
181 */
182 boolean allowEnums;
184 /** Switch: support boxing and unboxing?
185 */
186 boolean allowBoxing;
188 /** Switch: support covariant result types?
189 */
190 boolean allowCovariantReturns;
192 /** Switch: support lambda expressions ?
193 */
194 boolean allowLambda;
196 /** Switch: support default methods ?
197 */
198 boolean allowDefaultMethods;
200 /** Switch: allow references to surrounding object from anonymous
201 * objects during constructor call?
202 */
203 boolean allowAnonOuterThis;
205 /** Switch: generates a warning if diamond can be safely applied
206 * to a given new expression
207 */
208 boolean findDiamonds;
210 /**
211 * Internally enables/disables diamond finder feature
212 */
213 static final boolean allowDiamondFinder = true;
215 /**
216 * Switch: warn about use of variable before declaration?
217 * RFE: 6425594
218 */
219 boolean useBeforeDeclarationWarning;
221 /**
222 * Switch: generate warnings whenever an anonymous inner class that is convertible
223 * to a lambda expression is found
224 */
225 boolean identifyLambdaCandidate;
227 /**
228 * Switch: allow strings in switch?
229 */
230 boolean allowStringsInSwitch;
232 /**
233 * Switch: name of source level; used for error reporting.
234 */
235 String sourceName;
237 /** Check kind and type of given tree against protokind and prototype.
238 * If check succeeds, store type in tree and return it.
239 * If check fails, store errType in tree and return it.
240 * No checks are performed if the prototype is a method type.
241 * It is not necessary in this case since we know that kind and type
242 * are correct.
243 *
244 * @param tree The tree whose kind and type is checked
245 * @param ownkind The computed kind of the tree
246 * @param resultInfo The expected result of the tree
247 */
248 Type check(final JCTree tree, final Type found, final int ownkind, final ResultInfo resultInfo) {
249 InferenceContext inferenceContext = resultInfo.checkContext.inferenceContext();
250 Type owntype = found;
251 if (!owntype.hasTag(ERROR) && !resultInfo.pt.hasTag(METHOD) && !resultInfo.pt.hasTag(FORALL)) {
252 if (allowPoly && inferenceContext.free(found)) {
253 if ((ownkind & ~resultInfo.pkind) == 0) {
254 owntype = resultInfo.check(tree, inferenceContext.asFree(owntype));
255 } else {
256 log.error(tree.pos(), "unexpected.type",
257 kindNames(resultInfo.pkind),
258 kindName(ownkind));
259 owntype = types.createErrorType(owntype);
260 }
261 inferenceContext.addFreeTypeListener(List.of(found, resultInfo.pt), new FreeTypeListener() {
262 @Override
263 public void typesInferred(InferenceContext inferenceContext) {
264 ResultInfo pendingResult =
265 resultInfo.dup(inferenceContext.asInstType(resultInfo.pt));
266 check(tree, inferenceContext.asInstType(found), ownkind, pendingResult);
267 }
268 });
269 return tree.type = resultInfo.pt;
270 } else {
271 if ((ownkind & ~resultInfo.pkind) == 0) {
272 owntype = resultInfo.check(tree, owntype);
273 } else {
274 log.error(tree.pos(), "unexpected.type",
275 kindNames(resultInfo.pkind),
276 kindName(ownkind));
277 owntype = types.createErrorType(owntype);
278 }
279 }
280 }
281 tree.type = owntype;
282 return owntype;
283 }
285 /** Is given blank final variable assignable, i.e. in a scope where it
286 * may be assigned to even though it is final?
287 * @param v The blank final variable.
288 * @param env The current environment.
289 */
290 boolean isAssignableAsBlankFinal(VarSymbol v, Env<AttrContext> env) {
291 Symbol owner = owner(env);
292 // owner refers to the innermost variable, method or
293 // initializer block declaration at this point.
294 return
295 v.owner == owner
296 ||
297 ((owner.name == names.init || // i.e. we are in a constructor
298 owner.kind == VAR || // i.e. we are in a variable initializer
299 (owner.flags() & BLOCK) != 0) // i.e. we are in an initializer block
300 &&
301 v.owner == owner.owner
302 &&
303 ((v.flags() & STATIC) != 0) == Resolve.isStatic(env));
304 }
306 /**
307 * Return the innermost enclosing owner symbol in a given attribution context
308 */
309 Symbol owner(Env<AttrContext> env) {
310 while (true) {
311 switch (env.tree.getTag()) {
312 case VARDEF:
313 //a field can be owner
314 VarSymbol vsym = ((JCVariableDecl)env.tree).sym;
315 if (vsym.owner.kind == TYP) {
316 return vsym;
317 }
318 break;
319 case METHODDEF:
320 //method def is always an owner
321 return ((JCMethodDecl)env.tree).sym;
322 case CLASSDEF:
323 //class def is always an owner
324 return ((JCClassDecl)env.tree).sym;
325 case BLOCK:
326 //static/instance init blocks are owner
327 Symbol blockSym = env.info.scope.owner;
328 if ((blockSym.flags() & BLOCK) != 0) {
329 return blockSym;
330 }
331 break;
332 case TOPLEVEL:
333 //toplevel is always an owner (for pkge decls)
334 return env.info.scope.owner;
335 }
336 Assert.checkNonNull(env.next);
337 env = env.next;
338 }
339 }
341 /** Check that variable can be assigned to.
342 * @param pos The current source code position.
343 * @param v The assigned varaible
344 * @param base If the variable is referred to in a Select, the part
345 * to the left of the `.', null otherwise.
346 * @param env The current environment.
347 */
348 void checkAssignable(DiagnosticPosition pos, VarSymbol v, JCTree base, Env<AttrContext> env) {
349 if ((v.flags() & FINAL) != 0 &&
350 ((v.flags() & HASINIT) != 0
351 ||
352 !((base == null ||
353 (base.hasTag(IDENT) && TreeInfo.name(base) == names._this)) &&
354 isAssignableAsBlankFinal(v, env)))) {
355 if (v.isResourceVariable()) { //TWR resource
356 log.error(pos, "try.resource.may.not.be.assigned", v);
357 } else {
358 log.error(pos, "cant.assign.val.to.final.var", v);
359 }
360 }
361 }
363 /** Does tree represent a static reference to an identifier?
364 * It is assumed that tree is either a SELECT or an IDENT.
365 * We have to weed out selects from non-type names here.
366 * @param tree The candidate tree.
367 */
368 boolean isStaticReference(JCTree tree) {
369 if (tree.hasTag(SELECT)) {
370 Symbol lsym = TreeInfo.symbol(((JCFieldAccess) tree).selected);
371 if (lsym == null || lsym.kind != TYP) {
372 return false;
373 }
374 }
375 return true;
376 }
378 /** Is this symbol a type?
379 */
380 static boolean isType(Symbol sym) {
381 return sym != null && sym.kind == TYP;
382 }
384 /** The current `this' symbol.
385 * @param env The current environment.
386 */
387 Symbol thisSym(DiagnosticPosition pos, Env<AttrContext> env) {
388 return rs.resolveSelf(pos, env, env.enclClass.sym, names._this);
389 }
391 /** Attribute a parsed identifier.
392 * @param tree Parsed identifier name
393 * @param topLevel The toplevel to use
394 */
395 public Symbol attribIdent(JCTree tree, JCCompilationUnit topLevel) {
396 Env<AttrContext> localEnv = enter.topLevelEnv(topLevel);
397 localEnv.enclClass = make.ClassDef(make.Modifiers(0),
398 syms.errSymbol.name,
399 null, null, null, null);
400 localEnv.enclClass.sym = syms.errSymbol;
401 return tree.accept(identAttributer, localEnv);
402 }
403 // where
404 private TreeVisitor<Symbol,Env<AttrContext>> identAttributer = new IdentAttributer();
405 private class IdentAttributer extends SimpleTreeVisitor<Symbol,Env<AttrContext>> {
406 @Override
407 public Symbol visitMemberSelect(MemberSelectTree node, Env<AttrContext> env) {
408 Symbol site = visit(node.getExpression(), env);
409 if (site.kind == ERR || site.kind == ABSENT_TYP)
410 return site;
411 Name name = (Name)node.getIdentifier();
412 if (site.kind == PCK) {
413 env.toplevel.packge = (PackageSymbol)site;
414 return rs.findIdentInPackage(env, (TypeSymbol)site, name, TYP | PCK);
415 } else {
416 env.enclClass.sym = (ClassSymbol)site;
417 return rs.findMemberType(env, site.asType(), name, (TypeSymbol)site);
418 }
419 }
421 @Override
422 public Symbol visitIdentifier(IdentifierTree node, Env<AttrContext> env) {
423 return rs.findIdent(env, (Name)node.getName(), TYP | PCK);
424 }
425 }
427 public Type coerce(Type etype, Type ttype) {
428 return cfolder.coerce(etype, ttype);
429 }
431 public Type attribType(JCTree node, TypeSymbol sym) {
432 Env<AttrContext> env = enter.typeEnvs.get(sym);
433 Env<AttrContext> localEnv = env.dup(node, env.info.dup());
434 return attribTree(node, localEnv, unknownTypeInfo);
435 }
437 public Type attribImportQualifier(JCImport tree, Env<AttrContext> env) {
438 // Attribute qualifying package or class.
439 JCFieldAccess s = (JCFieldAccess)tree.qualid;
440 return attribTree(s.selected,
441 env,
442 new ResultInfo(tree.staticImport ? TYP : (TYP | PCK),
443 Type.noType));
444 }
446 public Env<AttrContext> attribExprToTree(JCTree expr, Env<AttrContext> env, JCTree tree) {
447 breakTree = tree;
448 JavaFileObject prev = log.useSource(env.toplevel.sourcefile);
449 try {
450 attribExpr(expr, env);
451 } catch (BreakAttr b) {
452 return b.env;
453 } catch (AssertionError ae) {
454 if (ae.getCause() instanceof BreakAttr) {
455 return ((BreakAttr)(ae.getCause())).env;
456 } else {
457 throw ae;
458 }
459 } finally {
460 breakTree = null;
461 log.useSource(prev);
462 }
463 return env;
464 }
466 public Env<AttrContext> attribStatToTree(JCTree stmt, Env<AttrContext> env, JCTree tree) {
467 breakTree = tree;
468 JavaFileObject prev = log.useSource(env.toplevel.sourcefile);
469 try {
470 attribStat(stmt, env);
471 } catch (BreakAttr b) {
472 return b.env;
473 } catch (AssertionError ae) {
474 if (ae.getCause() instanceof BreakAttr) {
475 return ((BreakAttr)(ae.getCause())).env;
476 } else {
477 throw ae;
478 }
479 } finally {
480 breakTree = null;
481 log.useSource(prev);
482 }
483 return env;
484 }
486 private JCTree breakTree = null;
488 private static class BreakAttr extends RuntimeException {
489 static final long serialVersionUID = -6924771130405446405L;
490 private Env<AttrContext> env;
491 private BreakAttr(Env<AttrContext> env) {
492 this.env = env;
493 }
494 }
496 class ResultInfo {
497 final int pkind;
498 final Type pt;
499 final CheckContext checkContext;
501 ResultInfo(int pkind, Type pt) {
502 this(pkind, pt, chk.basicHandler);
503 }
505 protected ResultInfo(int pkind, Type pt, CheckContext checkContext) {
506 this.pkind = pkind;
507 this.pt = pt;
508 this.checkContext = checkContext;
509 }
511 protected Type check(final DiagnosticPosition pos, final Type found) {
512 return chk.checkType(pos, found, pt, checkContext);
513 }
515 protected ResultInfo dup(Type newPt) {
516 return new ResultInfo(pkind, newPt, checkContext);
517 }
519 protected ResultInfo dup(CheckContext newContext) {
520 return new ResultInfo(pkind, pt, newContext);
521 }
523 @Override
524 public String toString() {
525 if (pt != null) {
526 return pt.toString();
527 } else {
528 return "";
529 }
530 }
531 }
533 class RecoveryInfo extends ResultInfo {
535 public RecoveryInfo(final DeferredAttr.DeferredAttrContext deferredAttrContext) {
536 super(Kinds.VAL, Type.recoveryType, new Check.NestedCheckContext(chk.basicHandler) {
537 @Override
538 public DeferredAttr.DeferredAttrContext deferredAttrContext() {
539 return deferredAttrContext;
540 }
541 @Override
542 public boolean compatible(Type found, Type req, Warner warn) {
543 return true;
544 }
545 @Override
546 public void report(DiagnosticPosition pos, JCDiagnostic details) {
547 chk.basicHandler.report(pos, details);
548 }
549 });
550 }
551 }
553 final ResultInfo statInfo;
554 final ResultInfo varInfo;
555 final ResultInfo unknownAnyPolyInfo;
556 final ResultInfo unknownExprInfo;
557 final ResultInfo unknownTypeInfo;
558 final ResultInfo unknownTypeExprInfo;
559 final ResultInfo recoveryInfo;
561 Type pt() {
562 return resultInfo.pt;
563 }
565 int pkind() {
566 return resultInfo.pkind;
567 }
569 /* ************************************************************************
570 * Visitor methods
571 *************************************************************************/
573 /** Visitor argument: the current environment.
574 */
575 Env<AttrContext> env;
577 /** Visitor argument: the currently expected attribution result.
578 */
579 ResultInfo resultInfo;
581 /** Visitor result: the computed type.
582 */
583 Type result;
585 /** Visitor method: attribute a tree, catching any completion failure
586 * exceptions. Return the tree's type.
587 *
588 * @param tree The tree to be visited.
589 * @param env The environment visitor argument.
590 * @param resultInfo The result info visitor argument.
591 */
592 Type attribTree(JCTree tree, Env<AttrContext> env, ResultInfo resultInfo) {
593 Env<AttrContext> prevEnv = this.env;
594 ResultInfo prevResult = this.resultInfo;
595 try {
596 this.env = env;
597 this.resultInfo = resultInfo;
598 tree.accept(this);
599 if (tree == breakTree &&
600 resultInfo.checkContext.deferredAttrContext().mode == AttrMode.CHECK) {
601 throw new BreakAttr(copyEnv(env));
602 }
603 return result;
604 } catch (CompletionFailure ex) {
605 tree.type = syms.errType;
606 return chk.completionError(tree.pos(), ex);
607 } finally {
608 this.env = prevEnv;
609 this.resultInfo = prevResult;
610 }
611 }
613 Env<AttrContext> copyEnv(Env<AttrContext> env) {
614 Env<AttrContext> newEnv =
615 env.dup(env.tree, env.info.dup(copyScope(env.info.scope)));
616 if (newEnv.outer != null) {
617 newEnv.outer = copyEnv(newEnv.outer);
618 }
619 return newEnv;
620 }
622 Scope copyScope(Scope sc) {
623 Scope newScope = new Scope(sc.owner);
624 List<Symbol> elemsList = List.nil();
625 while (sc != null) {
626 for (Scope.Entry e = sc.elems ; e != null ; e = e.sibling) {
627 elemsList = elemsList.prepend(e.sym);
628 }
629 sc = sc.next;
630 }
631 for (Symbol s : elemsList) {
632 newScope.enter(s);
633 }
634 return newScope;
635 }
637 /** Derived visitor method: attribute an expression tree.
638 */
639 public Type attribExpr(JCTree tree, Env<AttrContext> env, Type pt) {
640 return attribTree(tree, env, new ResultInfo(VAL, !pt.hasTag(ERROR) ? pt : Type.noType));
641 }
643 /** Derived visitor method: attribute an expression tree with
644 * no constraints on the computed type.
645 */
646 public Type attribExpr(JCTree tree, Env<AttrContext> env) {
647 return attribTree(tree, env, unknownExprInfo);
648 }
650 /** Derived visitor method: attribute a type tree.
651 */
652 public Type attribType(JCTree tree, Env<AttrContext> env) {
653 Type result = attribType(tree, env, Type.noType);
654 return result;
655 }
657 /** Derived visitor method: attribute a type tree.
658 */
659 Type attribType(JCTree tree, Env<AttrContext> env, Type pt) {
660 Type result = attribTree(tree, env, new ResultInfo(TYP, pt));
661 return result;
662 }
664 /** Derived visitor method: attribute a statement or definition tree.
665 */
666 public Type attribStat(JCTree tree, Env<AttrContext> env) {
667 return attribTree(tree, env, statInfo);
668 }
670 /** Attribute a list of expressions, returning a list of types.
671 */
672 List<Type> attribExprs(List<JCExpression> trees, Env<AttrContext> env, Type pt) {
673 ListBuffer<Type> ts = new ListBuffer<Type>();
674 for (List<JCExpression> l = trees; l.nonEmpty(); l = l.tail)
675 ts.append(attribExpr(l.head, env, pt));
676 return ts.toList();
677 }
679 /** Attribute a list of statements, returning nothing.
680 */
681 <T extends JCTree> void attribStats(List<T> trees, Env<AttrContext> env) {
682 for (List<T> l = trees; l.nonEmpty(); l = l.tail)
683 attribStat(l.head, env);
684 }
686 /** Attribute the arguments in a method call, returning the method kind.
687 */
688 int attribArgs(List<JCExpression> trees, Env<AttrContext> env, ListBuffer<Type> argtypes) {
689 int kind = VAL;
690 for (JCExpression arg : trees) {
691 Type argtype;
692 if (allowPoly && deferredAttr.isDeferred(env, arg)) {
693 argtype = deferredAttr.new DeferredType(arg, env);
694 kind |= POLY;
695 } else {
696 argtype = chk.checkNonVoid(arg, attribTree(arg, env, unknownAnyPolyInfo));
697 }
698 argtypes.append(argtype);
699 }
700 return kind;
701 }
703 /** Attribute a type argument list, returning a list of types.
704 * Caller is responsible for calling checkRefTypes.
705 */
706 List<Type> attribAnyTypes(List<JCExpression> trees, Env<AttrContext> env) {
707 ListBuffer<Type> argtypes = new ListBuffer<Type>();
708 for (List<JCExpression> l = trees; l.nonEmpty(); l = l.tail)
709 argtypes.append(attribType(l.head, env));
710 return argtypes.toList();
711 }
713 /** Attribute a type argument list, returning a list of types.
714 * Check that all the types are references.
715 */
716 List<Type> attribTypes(List<JCExpression> trees, Env<AttrContext> env) {
717 List<Type> types = attribAnyTypes(trees, env);
718 return chk.checkRefTypes(trees, types);
719 }
721 /**
722 * Attribute type variables (of generic classes or methods).
723 * Compound types are attributed later in attribBounds.
724 * @param typarams the type variables to enter
725 * @param env the current environment
726 */
727 void attribTypeVariables(List<JCTypeParameter> typarams, Env<AttrContext> env) {
728 for (JCTypeParameter tvar : typarams) {
729 TypeVar a = (TypeVar)tvar.type;
730 a.tsym.flags_field |= UNATTRIBUTED;
731 a.bound = Type.noType;
732 if (!tvar.bounds.isEmpty()) {
733 List<Type> bounds = List.of(attribType(tvar.bounds.head, env));
734 for (JCExpression bound : tvar.bounds.tail)
735 bounds = bounds.prepend(attribType(bound, env));
736 types.setBounds(a, bounds.reverse());
737 } else {
738 // if no bounds are given, assume a single bound of
739 // java.lang.Object.
740 types.setBounds(a, List.of(syms.objectType));
741 }
742 a.tsym.flags_field &= ~UNATTRIBUTED;
743 }
744 for (JCTypeParameter tvar : typarams) {
745 chk.checkNonCyclic(tvar.pos(), (TypeVar)tvar.type);
746 }
747 }
749 /**
750 * Attribute the type references in a list of annotations.
751 */
752 void attribAnnotationTypes(List<JCAnnotation> annotations,
753 Env<AttrContext> env) {
754 for (List<JCAnnotation> al = annotations; al.nonEmpty(); al = al.tail) {
755 JCAnnotation a = al.head;
756 attribType(a.annotationType, env);
757 }
758 }
760 /**
761 * Attribute a "lazy constant value".
762 * @param env The env for the const value
763 * @param initializer The initializer for the const value
764 * @param type The expected type, or null
765 * @see VarSymbol#setLazyConstValue
766 */
767 public Object attribLazyConstantValue(Env<AttrContext> env,
768 JCVariableDecl variable,
769 Type type) {
771 DiagnosticPosition prevLintPos
772 = deferredLintHandler.setPos(variable.pos());
774 try {
775 // Use null as symbol to not attach the type annotation to any symbol.
776 // The initializer will later also be visited and then we'll attach
777 // to the symbol.
778 // This prevents having multiple type annotations, just because of
779 // lazy constant value evaluation.
780 memberEnter.typeAnnotate(variable.init, env, null, variable.pos());
781 annotate.flush();
782 Type itype = attribExpr(variable.init, env, type);
783 if (itype.constValue() != null) {
784 return coerce(itype, type).constValue();
785 } else {
786 return null;
787 }
788 } finally {
789 deferredLintHandler.setPos(prevLintPos);
790 }
791 }
793 /** Attribute type reference in an `extends' or `implements' clause.
794 * Supertypes of anonymous inner classes are usually already attributed.
795 *
796 * @param tree The tree making up the type reference.
797 * @param env The environment current at the reference.
798 * @param classExpected true if only a class is expected here.
799 * @param interfaceExpected true if only an interface is expected here.
800 */
801 Type attribBase(JCTree tree,
802 Env<AttrContext> env,
803 boolean classExpected,
804 boolean interfaceExpected,
805 boolean checkExtensible) {
806 Type t = tree.type != null ?
807 tree.type :
808 attribType(tree, env);
809 return checkBase(t, tree, env, classExpected, interfaceExpected, false, checkExtensible);
810 }
811 Type checkBase(Type t,
812 JCTree tree,
813 Env<AttrContext> env,
814 boolean classExpected,
815 boolean interfacesOnlyExpected,
816 boolean interfacesOrArraysExpected,
817 boolean checkExtensible) {
818 if (t.isErroneous())
819 return t;
820 if (t.hasTag(TYPEVAR) && !classExpected &&
821 !interfacesOrArraysExpected && !interfacesOnlyExpected) {
822 // check that type variable is already visible
823 if (t.getUpperBound() == null) {
824 log.error(tree.pos(), "illegal.forward.ref");
825 return types.createErrorType(t);
826 }
827 } else if (classExpected) {
828 t = chk.checkClassType(tree.pos(), t, checkExtensible|!allowGenerics);
829 } else {
830 t = chk.checkClassOrArrayType(tree.pos(), t,
831 checkExtensible|!allowGenerics);
832 }
833 if (interfacesOnlyExpected && !t.tsym.isInterface()) {
834 log.error(tree.pos(), "intf.expected.here");
835 // return errType is necessary since otherwise there might
836 // be undetected cycles which cause attribution to loop
837 return types.createErrorType(t);
838 } else if (interfacesOrArraysExpected &&
839 !(t.tsym.isInterface() || t.getTag() == ARRAY)) {
840 log.error(tree.pos(), "intf.or.array.expected.here");
841 // return errType is necessary since otherwise there might
842 // be undetected cycles which cause attribution to loop
843 return types.createErrorType(t);
844 } else if (checkExtensible &&
845 classExpected &&
846 t.tsym.isInterface()) {
847 log.error(tree.pos(), "no.intf.expected.here");
848 return types.createErrorType(t);
849 }
850 if (checkExtensible &&
851 ((t.tsym.flags() & FINAL) != 0)) {
852 log.error(tree.pos(),
853 "cant.inherit.from.final", t.tsym);
854 }
855 chk.checkNonCyclic(tree.pos(), t);
856 return t;
857 }
858 //where
859 private Object asTypeParam(Type t) {
860 return (t.hasTag(TYPEVAR))
861 ? diags.fragment("type.parameter", t)
862 : t;
863 }
865 Type attribIdentAsEnumType(Env<AttrContext> env, JCIdent id) {
866 Assert.check((env.enclClass.sym.flags() & ENUM) != 0);
867 id.type = env.info.scope.owner.type;
868 id.sym = env.info.scope.owner;
869 return id.type;
870 }
872 public void visitClassDef(JCClassDecl tree) {
873 // Local classes have not been entered yet, so we need to do it now:
874 if ((env.info.scope.owner.kind & (VAR | MTH)) != 0)
875 enter.classEnter(tree, env);
877 ClassSymbol c = tree.sym;
878 if (c == null) {
879 // exit in case something drastic went wrong during enter.
880 result = null;
881 } else {
882 // make sure class has been completed:
883 c.complete();
885 // If this class appears as an anonymous class
886 // in a superclass constructor call where
887 // no explicit outer instance is given,
888 // disable implicit outer instance from being passed.
889 // (This would be an illegal access to "this before super").
890 if (env.info.isSelfCall &&
891 env.tree.hasTag(NEWCLASS) &&
892 ((JCNewClass) env.tree).encl == null)
893 {
894 c.flags_field |= NOOUTERTHIS;
895 }
896 attribClass(tree.pos(), c);
897 result = tree.type = c.type;
898 }
899 }
901 public void visitMethodDef(JCMethodDecl tree) {
902 MethodSymbol m = tree.sym;
903 boolean isDefaultMethod = (m.flags() & DEFAULT) != 0;
905 Lint lint = env.info.lint.augment(m);
906 Lint prevLint = chk.setLint(lint);
907 MethodSymbol prevMethod = chk.setMethod(m);
908 try {
909 deferredLintHandler.flush(tree.pos());
910 chk.checkDeprecatedAnnotation(tree.pos(), m);
913 // Create a new environment with local scope
914 // for attributing the method.
915 Env<AttrContext> localEnv = memberEnter.methodEnv(tree, env);
916 localEnv.info.lint = lint;
918 attribStats(tree.typarams, localEnv);
920 // If we override any other methods, check that we do so properly.
921 // JLS ???
922 if (m.isStatic()) {
923 chk.checkHideClashes(tree.pos(), env.enclClass.type, m);
924 } else {
925 chk.checkOverrideClashes(tree.pos(), env.enclClass.type, m);
926 }
927 chk.checkOverride(tree, m);
929 if (isDefaultMethod && types.overridesObjectMethod(m.enclClass(), m)) {
930 log.error(tree, "default.overrides.object.member", m.name, Kinds.kindName(m.location()), m.location());
931 }
933 // Enter all type parameters into the local method scope.
934 for (List<JCTypeParameter> l = tree.typarams; l.nonEmpty(); l = l.tail)
935 localEnv.info.scope.enterIfAbsent(l.head.type.tsym);
937 ClassSymbol owner = env.enclClass.sym;
938 if ((owner.flags() & ANNOTATION) != 0 &&
939 tree.params.nonEmpty())
940 log.error(tree.params.head.pos(),
941 "intf.annotation.members.cant.have.params");
943 // Attribute all value parameters.
944 for (List<JCVariableDecl> l = tree.params; l.nonEmpty(); l = l.tail) {
945 attribStat(l.head, localEnv);
946 }
948 chk.checkVarargsMethodDecl(localEnv, tree);
950 // Check that type parameters are well-formed.
951 chk.validate(tree.typarams, localEnv);
953 // Check that result type is well-formed.
954 chk.validate(tree.restype, localEnv);
956 // Check that receiver type is well-formed.
957 if (tree.recvparam != null) {
958 // Use a new environment to check the receiver parameter.
959 // Otherwise I get "might not have been initialized" errors.
960 // Is there a better way?
961 Env<AttrContext> newEnv = memberEnter.methodEnv(tree, env);
962 attribType(tree.recvparam, newEnv);
963 chk.validate(tree.recvparam, newEnv);
964 }
966 // annotation method checks
967 if ((owner.flags() & ANNOTATION) != 0) {
968 // annotation method cannot have throws clause
969 if (tree.thrown.nonEmpty()) {
970 log.error(tree.thrown.head.pos(),
971 "throws.not.allowed.in.intf.annotation");
972 }
973 // annotation method cannot declare type-parameters
974 if (tree.typarams.nonEmpty()) {
975 log.error(tree.typarams.head.pos(),
976 "intf.annotation.members.cant.have.type.params");
977 }
978 // validate annotation method's return type (could be an annotation type)
979 chk.validateAnnotationType(tree.restype);
980 // ensure that annotation method does not clash with members of Object/Annotation
981 chk.validateAnnotationMethod(tree.pos(), m);
982 }
984 for (List<JCExpression> l = tree.thrown; l.nonEmpty(); l = l.tail)
985 chk.checkType(l.head.pos(), l.head.type, syms.throwableType);
987 if (tree.body == null) {
988 // Empty bodies are only allowed for
989 // abstract, native, or interface methods, or for methods
990 // in a retrofit signature class.
991 if (isDefaultMethod || (tree.sym.flags() & (ABSTRACT | NATIVE)) == 0 &&
992 !relax)
993 log.error(tree.pos(), "missing.meth.body.or.decl.abstract");
994 if (tree.defaultValue != null) {
995 if ((owner.flags() & ANNOTATION) == 0)
996 log.error(tree.pos(),
997 "default.allowed.in.intf.annotation.member");
998 }
999 } else if ((tree.sym.flags() & ABSTRACT) != 0 && !isDefaultMethod) {
1000 if ((owner.flags() & INTERFACE) != 0) {
1001 log.error(tree.body.pos(), "intf.meth.cant.have.body");
1002 } else {
1003 log.error(tree.pos(), "abstract.meth.cant.have.body");
1004 }
1005 } else if ((tree.mods.flags & NATIVE) != 0) {
1006 log.error(tree.pos(), "native.meth.cant.have.body");
1007 } else {
1008 // Add an implicit super() call unless an explicit call to
1009 // super(...) or this(...) is given
1010 // or we are compiling class java.lang.Object.
1011 if (tree.name == names.init && owner.type != syms.objectType) {
1012 JCBlock body = tree.body;
1013 if (body.stats.isEmpty() ||
1014 !TreeInfo.isSelfCall(body.stats.head)) {
1015 body.stats = body.stats.
1016 prepend(memberEnter.SuperCall(make.at(body.pos),
1017 List.<Type>nil(),
1018 List.<JCVariableDecl>nil(),
1019 false));
1020 } else if ((env.enclClass.sym.flags() & ENUM) != 0 &&
1021 (tree.mods.flags & GENERATEDCONSTR) == 0 &&
1022 TreeInfo.isSuperCall(body.stats.head)) {
1023 // enum constructors are not allowed to call super
1024 // directly, so make sure there aren't any super calls
1025 // in enum constructors, except in the compiler
1026 // generated one.
1027 log.error(tree.body.stats.head.pos(),
1028 "call.to.super.not.allowed.in.enum.ctor",
1029 env.enclClass.sym);
1030 }
1031 }
1033 // Attribute all type annotations in the body
1034 memberEnter.typeAnnotate(tree.body, localEnv, m, null);
1035 annotate.flush();
1037 // Attribute method body.
1038 attribStat(tree.body, localEnv);
1039 }
1041 localEnv.info.scope.leave();
1042 result = tree.type = m.type;
1043 }
1044 finally {
1045 chk.setLint(prevLint);
1046 chk.setMethod(prevMethod);
1047 }
1048 }
1050 public void visitVarDef(JCVariableDecl tree) {
1051 // Local variables have not been entered yet, so we need to do it now:
1052 if (env.info.scope.owner.kind == MTH) {
1053 if (tree.sym != null) {
1054 // parameters have already been entered
1055 env.info.scope.enter(tree.sym);
1056 } else {
1057 memberEnter.memberEnter(tree, env);
1058 annotate.flush();
1059 }
1060 } else {
1061 if (tree.init != null) {
1062 // Field initializer expression need to be entered.
1063 memberEnter.typeAnnotate(tree.init, env, tree.sym, tree.pos());
1064 annotate.flush();
1065 }
1066 }
1068 VarSymbol v = tree.sym;
1069 Lint lint = env.info.lint.augment(v);
1070 Lint prevLint = chk.setLint(lint);
1072 // Check that the variable's declared type is well-formed.
1073 boolean isImplicitLambdaParameter = env.tree.hasTag(LAMBDA) &&
1074 ((JCLambda)env.tree).paramKind == JCLambda.ParameterKind.IMPLICIT &&
1075 (tree.sym.flags() & PARAMETER) != 0;
1076 chk.validate(tree.vartype, env, !isImplicitLambdaParameter);
1078 try {
1079 v.getConstValue(); // ensure compile-time constant initializer is evaluated
1080 deferredLintHandler.flush(tree.pos());
1081 chk.checkDeprecatedAnnotation(tree.pos(), v);
1083 if (tree.init != null) {
1084 if ((v.flags_field & FINAL) == 0 ||
1085 !memberEnter.needsLazyConstValue(tree.init)) {
1086 // Not a compile-time constant
1087 // Attribute initializer in a new environment
1088 // with the declared variable as owner.
1089 // Check that initializer conforms to variable's declared type.
1090 Env<AttrContext> initEnv = memberEnter.initEnv(tree, env);
1091 initEnv.info.lint = lint;
1092 // In order to catch self-references, we set the variable's
1093 // declaration position to maximal possible value, effectively
1094 // marking the variable as undefined.
1095 initEnv.info.enclVar = v;
1096 attribExpr(tree.init, initEnv, v.type);
1097 }
1098 }
1099 result = tree.type = v.type;
1100 }
1101 finally {
1102 chk.setLint(prevLint);
1103 }
1104 }
1106 public void visitSkip(JCSkip tree) {
1107 result = null;
1108 }
1110 public void visitBlock(JCBlock tree) {
1111 if (env.info.scope.owner.kind == TYP) {
1112 // Block is a static or instance initializer;
1113 // let the owner of the environment be a freshly
1114 // created BLOCK-method.
1115 Env<AttrContext> localEnv =
1116 env.dup(tree, env.info.dup(env.info.scope.dupUnshared()));
1117 localEnv.info.scope.owner =
1118 new MethodSymbol(tree.flags | BLOCK |
1119 env.info.scope.owner.flags() & STRICTFP, names.empty, null,
1120 env.info.scope.owner);
1121 if ((tree.flags & STATIC) != 0) localEnv.info.staticLevel++;
1123 // Attribute all type annotations in the block
1124 memberEnter.typeAnnotate(tree, localEnv, localEnv.info.scope.owner, null);
1125 annotate.flush();
1127 {
1128 // Store init and clinit type annotations with the ClassSymbol
1129 // to allow output in Gen.normalizeDefs.
1130 ClassSymbol cs = (ClassSymbol)env.info.scope.owner;
1131 List<Attribute.TypeCompound> tas = localEnv.info.scope.owner.getRawTypeAttributes();
1132 if ((tree.flags & STATIC) != 0) {
1133 cs.appendClassInitTypeAttributes(tas);
1134 } else {
1135 cs.appendInitTypeAttributes(tas);
1136 }
1137 }
1139 attribStats(tree.stats, localEnv);
1140 } else {
1141 // Create a new local environment with a local scope.
1142 Env<AttrContext> localEnv =
1143 env.dup(tree, env.info.dup(env.info.scope.dup()));
1144 try {
1145 attribStats(tree.stats, localEnv);
1146 } finally {
1147 localEnv.info.scope.leave();
1148 }
1149 }
1150 result = null;
1151 }
1153 public void visitDoLoop(JCDoWhileLoop tree) {
1154 attribStat(tree.body, env.dup(tree));
1155 attribExpr(tree.cond, env, syms.booleanType);
1156 result = null;
1157 }
1159 public void visitWhileLoop(JCWhileLoop tree) {
1160 attribExpr(tree.cond, env, syms.booleanType);
1161 attribStat(tree.body, env.dup(tree));
1162 result = null;
1163 }
1165 public void visitForLoop(JCForLoop tree) {
1166 Env<AttrContext> loopEnv =
1167 env.dup(env.tree, env.info.dup(env.info.scope.dup()));
1168 try {
1169 attribStats(tree.init, loopEnv);
1170 if (tree.cond != null) attribExpr(tree.cond, loopEnv, syms.booleanType);
1171 loopEnv.tree = tree; // before, we were not in loop!
1172 attribStats(tree.step, loopEnv);
1173 attribStat(tree.body, loopEnv);
1174 result = null;
1175 }
1176 finally {
1177 loopEnv.info.scope.leave();
1178 }
1179 }
1181 public void visitForeachLoop(JCEnhancedForLoop tree) {
1182 Env<AttrContext> loopEnv =
1183 env.dup(env.tree, env.info.dup(env.info.scope.dup()));
1184 try {
1185 //the Formal Parameter of a for-each loop is not in the scope when
1186 //attributing the for-each expression; we mimick this by attributing
1187 //the for-each expression first (against original scope).
1188 Type exprType = types.upperBound(attribExpr(tree.expr, loopEnv));
1189 attribStat(tree.var, loopEnv);
1190 chk.checkNonVoid(tree.pos(), exprType);
1191 Type elemtype = types.elemtype(exprType); // perhaps expr is an array?
1192 if (elemtype == null) {
1193 // or perhaps expr implements Iterable<T>?
1194 Type base = types.asSuper(exprType, syms.iterableType.tsym);
1195 if (base == null) {
1196 log.error(tree.expr.pos(),
1197 "foreach.not.applicable.to.type",
1198 exprType,
1199 diags.fragment("type.req.array.or.iterable"));
1200 elemtype = types.createErrorType(exprType);
1201 } else {
1202 List<Type> iterableParams = base.allparams();
1203 elemtype = iterableParams.isEmpty()
1204 ? syms.objectType
1205 : types.upperBound(iterableParams.head);
1206 }
1207 }
1208 chk.checkType(tree.expr.pos(), elemtype, tree.var.sym.type);
1209 loopEnv.tree = tree; // before, we were not in loop!
1210 attribStat(tree.body, loopEnv);
1211 result = null;
1212 }
1213 finally {
1214 loopEnv.info.scope.leave();
1215 }
1216 }
1218 public void visitLabelled(JCLabeledStatement tree) {
1219 // Check that label is not used in an enclosing statement
1220 Env<AttrContext> env1 = env;
1221 while (env1 != null && !env1.tree.hasTag(CLASSDEF)) {
1222 if (env1.tree.hasTag(LABELLED) &&
1223 ((JCLabeledStatement) env1.tree).label == tree.label) {
1224 log.error(tree.pos(), "label.already.in.use",
1225 tree.label);
1226 break;
1227 }
1228 env1 = env1.next;
1229 }
1231 attribStat(tree.body, env.dup(tree));
1232 result = null;
1233 }
1235 public void visitSwitch(JCSwitch tree) {
1236 Type seltype = attribExpr(tree.selector, env);
1238 Env<AttrContext> switchEnv =
1239 env.dup(tree, env.info.dup(env.info.scope.dup()));
1241 try {
1243 boolean enumSwitch =
1244 allowEnums &&
1245 (seltype.tsym.flags() & Flags.ENUM) != 0;
1246 boolean stringSwitch = false;
1247 if (types.isSameType(seltype, syms.stringType)) {
1248 if (allowStringsInSwitch) {
1249 stringSwitch = true;
1250 } else {
1251 log.error(tree.selector.pos(), "string.switch.not.supported.in.source", sourceName);
1252 }
1253 }
1254 if (!enumSwitch && !stringSwitch)
1255 seltype = chk.checkType(tree.selector.pos(), seltype, syms.intType);
1257 // Attribute all cases and
1258 // check that there are no duplicate case labels or default clauses.
1259 Set<Object> labels = new HashSet<Object>(); // The set of case labels.
1260 boolean hasDefault = false; // Is there a default label?
1261 for (List<JCCase> l = tree.cases; l.nonEmpty(); l = l.tail) {
1262 JCCase c = l.head;
1263 Env<AttrContext> caseEnv =
1264 switchEnv.dup(c, env.info.dup(switchEnv.info.scope.dup()));
1265 try {
1266 if (c.pat != null) {
1267 if (enumSwitch) {
1268 Symbol sym = enumConstant(c.pat, seltype);
1269 if (sym == null) {
1270 log.error(c.pat.pos(), "enum.label.must.be.unqualified.enum");
1271 } else if (!labels.add(sym)) {
1272 log.error(c.pos(), "duplicate.case.label");
1273 }
1274 } else {
1275 Type pattype = attribExpr(c.pat, switchEnv, seltype);
1276 if (!pattype.hasTag(ERROR)) {
1277 if (pattype.constValue() == null) {
1278 log.error(c.pat.pos(),
1279 (stringSwitch ? "string.const.req" : "const.expr.req"));
1280 } else if (labels.contains(pattype.constValue())) {
1281 log.error(c.pos(), "duplicate.case.label");
1282 } else {
1283 labels.add(pattype.constValue());
1284 }
1285 }
1286 }
1287 } else if (hasDefault) {
1288 log.error(c.pos(), "duplicate.default.label");
1289 } else {
1290 hasDefault = true;
1291 }
1292 attribStats(c.stats, caseEnv);
1293 } finally {
1294 caseEnv.info.scope.leave();
1295 addVars(c.stats, switchEnv.info.scope);
1296 }
1297 }
1299 result = null;
1300 }
1301 finally {
1302 switchEnv.info.scope.leave();
1303 }
1304 }
1305 // where
1306 /** Add any variables defined in stats to the switch scope. */
1307 private static void addVars(List<JCStatement> stats, Scope switchScope) {
1308 for (;stats.nonEmpty(); stats = stats.tail) {
1309 JCTree stat = stats.head;
1310 if (stat.hasTag(VARDEF))
1311 switchScope.enter(((JCVariableDecl) stat).sym);
1312 }
1313 }
1314 // where
1315 /** Return the selected enumeration constant symbol, or null. */
1316 private Symbol enumConstant(JCTree tree, Type enumType) {
1317 if (!tree.hasTag(IDENT)) {
1318 log.error(tree.pos(), "enum.label.must.be.unqualified.enum");
1319 return syms.errSymbol;
1320 }
1321 JCIdent ident = (JCIdent)tree;
1322 Name name = ident.name;
1323 for (Scope.Entry e = enumType.tsym.members().lookup(name);
1324 e.scope != null; e = e.next()) {
1325 if (e.sym.kind == VAR) {
1326 Symbol s = ident.sym = e.sym;
1327 ((VarSymbol)s).getConstValue(); // ensure initializer is evaluated
1328 ident.type = s.type;
1329 return ((s.flags_field & Flags.ENUM) == 0)
1330 ? null : s;
1331 }
1332 }
1333 return null;
1334 }
1336 public void visitSynchronized(JCSynchronized tree) {
1337 chk.checkRefType(tree.pos(), attribExpr(tree.lock, env));
1338 attribStat(tree.body, env);
1339 result = null;
1340 }
1342 public void visitTry(JCTry tree) {
1343 // Create a new local environment with a local
1344 Env<AttrContext> localEnv = env.dup(tree, env.info.dup(env.info.scope.dup()));
1345 try {
1346 boolean isTryWithResource = tree.resources.nonEmpty();
1347 // Create a nested environment for attributing the try block if needed
1348 Env<AttrContext> tryEnv = isTryWithResource ?
1349 env.dup(tree, localEnv.info.dup(localEnv.info.scope.dup())) :
1350 localEnv;
1351 try {
1352 // Attribute resource declarations
1353 for (JCTree resource : tree.resources) {
1354 CheckContext twrContext = new Check.NestedCheckContext(resultInfo.checkContext) {
1355 @Override
1356 public void report(DiagnosticPosition pos, JCDiagnostic details) {
1357 chk.basicHandler.report(pos, diags.fragment("try.not.applicable.to.type", details));
1358 }
1359 };
1360 ResultInfo twrResult = new ResultInfo(VAL, syms.autoCloseableType, twrContext);
1361 if (resource.hasTag(VARDEF)) {
1362 attribStat(resource, tryEnv);
1363 twrResult.check(resource, resource.type);
1365 //check that resource type cannot throw InterruptedException
1366 checkAutoCloseable(resource.pos(), localEnv, resource.type);
1368 VarSymbol var = ((JCVariableDecl) resource).sym;
1369 var.setData(ElementKind.RESOURCE_VARIABLE);
1370 } else {
1371 attribTree(resource, tryEnv, twrResult);
1372 }
1373 }
1374 // Attribute body
1375 attribStat(tree.body, tryEnv);
1376 } finally {
1377 if (isTryWithResource)
1378 tryEnv.info.scope.leave();
1379 }
1381 // Attribute catch clauses
1382 for (List<JCCatch> l = tree.catchers; l.nonEmpty(); l = l.tail) {
1383 JCCatch c = l.head;
1384 Env<AttrContext> catchEnv =
1385 localEnv.dup(c, localEnv.info.dup(localEnv.info.scope.dup()));
1386 try {
1387 Type ctype = attribStat(c.param, catchEnv);
1388 if (TreeInfo.isMultiCatch(c)) {
1389 //multi-catch parameter is implicitly marked as final
1390 c.param.sym.flags_field |= FINAL | UNION;
1391 }
1392 if (c.param.sym.kind == Kinds.VAR) {
1393 c.param.sym.setData(ElementKind.EXCEPTION_PARAMETER);
1394 }
1395 chk.checkType(c.param.vartype.pos(),
1396 chk.checkClassType(c.param.vartype.pos(), ctype),
1397 syms.throwableType);
1398 attribStat(c.body, catchEnv);
1399 } finally {
1400 catchEnv.info.scope.leave();
1401 }
1402 }
1404 // Attribute finalizer
1405 if (tree.finalizer != null) attribStat(tree.finalizer, localEnv);
1406 result = null;
1407 }
1408 finally {
1409 localEnv.info.scope.leave();
1410 }
1411 }
1413 void checkAutoCloseable(DiagnosticPosition pos, Env<AttrContext> env, Type resource) {
1414 if (!resource.isErroneous() &&
1415 types.asSuper(resource, syms.autoCloseableType.tsym) != null &&
1416 !types.isSameType(resource, syms.autoCloseableType)) { // Don't emit warning for AutoCloseable itself
1417 Symbol close = syms.noSymbol;
1418 Log.DiagnosticHandler discardHandler = new Log.DiscardDiagnosticHandler(log);
1419 try {
1420 close = rs.resolveQualifiedMethod(pos,
1421 env,
1422 resource,
1423 names.close,
1424 List.<Type>nil(),
1425 List.<Type>nil());
1426 }
1427 finally {
1428 log.popDiagnosticHandler(discardHandler);
1429 }
1430 if (close.kind == MTH &&
1431 close.overrides(syms.autoCloseableClose, resource.tsym, types, true) &&
1432 chk.isHandled(syms.interruptedExceptionType, types.memberType(resource, close).getThrownTypes()) &&
1433 env.info.lint.isEnabled(LintCategory.TRY)) {
1434 log.warning(LintCategory.TRY, pos, "try.resource.throws.interrupted.exc", resource);
1435 }
1436 }
1437 }
1439 public void visitConditional(JCConditional tree) {
1440 Type condtype = attribExpr(tree.cond, env, syms.booleanType);
1442 tree.polyKind = (!allowPoly ||
1443 pt().hasTag(NONE) && pt() != Type.recoveryType ||
1444 isBooleanOrNumeric(env, tree)) ?
1445 PolyKind.STANDALONE : PolyKind.POLY;
1447 if (tree.polyKind == PolyKind.POLY && resultInfo.pt.hasTag(VOID)) {
1448 //cannot get here (i.e. it means we are returning from void method - which is already an error)
1449 resultInfo.checkContext.report(tree, diags.fragment("conditional.target.cant.be.void"));
1450 result = tree.type = types.createErrorType(resultInfo.pt);
1451 return;
1452 }
1454 ResultInfo condInfo = tree.polyKind == PolyKind.STANDALONE ?
1455 unknownExprInfo :
1456 resultInfo.dup(new Check.NestedCheckContext(resultInfo.checkContext) {
1457 //this will use enclosing check context to check compatibility of
1458 //subexpression against target type; if we are in a method check context,
1459 //depending on whether boxing is allowed, we could have incompatibilities
1460 @Override
1461 public void report(DiagnosticPosition pos, JCDiagnostic details) {
1462 enclosingContext.report(pos, diags.fragment("incompatible.type.in.conditional", details));
1463 }
1464 });
1466 Type truetype = attribTree(tree.truepart, env, condInfo);
1467 Type falsetype = attribTree(tree.falsepart, env, condInfo);
1469 Type owntype = (tree.polyKind == PolyKind.STANDALONE) ? condType(tree, truetype, falsetype) : pt();
1470 if (condtype.constValue() != null &&
1471 truetype.constValue() != null &&
1472 falsetype.constValue() != null &&
1473 !owntype.hasTag(NONE)) {
1474 //constant folding
1475 owntype = cfolder.coerce(condtype.isTrue() ? truetype : falsetype, owntype);
1476 }
1477 result = check(tree, owntype, VAL, resultInfo);
1478 }
1479 //where
1480 private boolean isBooleanOrNumeric(Env<AttrContext> env, JCExpression tree) {
1481 switch (tree.getTag()) {
1482 case LITERAL: return ((JCLiteral)tree).typetag.isSubRangeOf(DOUBLE) ||
1483 ((JCLiteral)tree).typetag == BOOLEAN ||
1484 ((JCLiteral)tree).typetag == BOT;
1485 case LAMBDA: case REFERENCE: return false;
1486 case PARENS: return isBooleanOrNumeric(env, ((JCParens)tree).expr);
1487 case CONDEXPR:
1488 JCConditional condTree = (JCConditional)tree;
1489 return isBooleanOrNumeric(env, condTree.truepart) &&
1490 isBooleanOrNumeric(env, condTree.falsepart);
1491 case APPLY:
1492 JCMethodInvocation speculativeMethodTree =
1493 (JCMethodInvocation)deferredAttr.attribSpeculative(tree, env, unknownExprInfo);
1494 Type owntype = TreeInfo.symbol(speculativeMethodTree.meth).type.getReturnType();
1495 return types.unboxedTypeOrType(owntype).isPrimitive();
1496 case NEWCLASS:
1497 JCExpression className =
1498 removeClassParams.translate(((JCNewClass)tree).clazz);
1499 JCExpression speculativeNewClassTree =
1500 (JCExpression)deferredAttr.attribSpeculative(className, env, unknownTypeInfo);
1501 return types.unboxedTypeOrType(speculativeNewClassTree.type).isPrimitive();
1502 default:
1503 Type speculativeType = deferredAttr.attribSpeculative(tree, env, unknownExprInfo).type;
1504 speculativeType = types.unboxedTypeOrType(speculativeType);
1505 return speculativeType.isPrimitive();
1506 }
1507 }
1508 //where
1509 TreeTranslator removeClassParams = new TreeTranslator() {
1510 @Override
1511 public void visitTypeApply(JCTypeApply tree) {
1512 result = translate(tree.clazz);
1513 }
1514 };
1516 /** Compute the type of a conditional expression, after
1517 * checking that it exists. See JLS 15.25. Does not take into
1518 * account the special case where condition and both arms
1519 * are constants.
1520 *
1521 * @param pos The source position to be used for error
1522 * diagnostics.
1523 * @param thentype The type of the expression's then-part.
1524 * @param elsetype The type of the expression's else-part.
1525 */
1526 private Type condType(DiagnosticPosition pos,
1527 Type thentype, Type elsetype) {
1528 // If same type, that is the result
1529 if (types.isSameType(thentype, elsetype))
1530 return thentype.baseType();
1532 Type thenUnboxed = (!allowBoxing || thentype.isPrimitive())
1533 ? thentype : types.unboxedType(thentype);
1534 Type elseUnboxed = (!allowBoxing || elsetype.isPrimitive())
1535 ? elsetype : types.unboxedType(elsetype);
1537 // Otherwise, if both arms can be converted to a numeric
1538 // type, return the least numeric type that fits both arms
1539 // (i.e. return larger of the two, or return int if one
1540 // arm is short, the other is char).
1541 if (thenUnboxed.isPrimitive() && elseUnboxed.isPrimitive()) {
1542 // If one arm has an integer subrange type (i.e., byte,
1543 // short, or char), and the other is an integer constant
1544 // that fits into the subrange, return the subrange type.
1545 if (thenUnboxed.getTag().isStrictSubRangeOf(INT) &&
1546 elseUnboxed.hasTag(INT) &&
1547 types.isAssignable(elseUnboxed, thenUnboxed)) {
1548 return thenUnboxed.baseType();
1549 }
1550 if (elseUnboxed.getTag().isStrictSubRangeOf(INT) &&
1551 thenUnboxed.hasTag(INT) &&
1552 types.isAssignable(thenUnboxed, elseUnboxed)) {
1553 return elseUnboxed.baseType();
1554 }
1556 for (TypeTag tag : primitiveTags) {
1557 Type candidate = syms.typeOfTag[tag.ordinal()];
1558 if (types.isSubtype(thenUnboxed, candidate) &&
1559 types.isSubtype(elseUnboxed, candidate)) {
1560 return candidate;
1561 }
1562 }
1563 }
1565 // Those were all the cases that could result in a primitive
1566 if (allowBoxing) {
1567 if (thentype.isPrimitive())
1568 thentype = types.boxedClass(thentype).type;
1569 if (elsetype.isPrimitive())
1570 elsetype = types.boxedClass(elsetype).type;
1571 }
1573 if (types.isSubtype(thentype, elsetype))
1574 return elsetype.baseType();
1575 if (types.isSubtype(elsetype, thentype))
1576 return thentype.baseType();
1578 if (!allowBoxing || thentype.hasTag(VOID) || elsetype.hasTag(VOID)) {
1579 log.error(pos, "neither.conditional.subtype",
1580 thentype, elsetype);
1581 return thentype.baseType();
1582 }
1584 // both are known to be reference types. The result is
1585 // lub(thentype,elsetype). This cannot fail, as it will
1586 // always be possible to infer "Object" if nothing better.
1587 return types.lub(thentype.baseType(), elsetype.baseType());
1588 }
1590 final static TypeTag[] primitiveTags = new TypeTag[]{
1591 BYTE,
1592 CHAR,
1593 SHORT,
1594 INT,
1595 LONG,
1596 FLOAT,
1597 DOUBLE,
1598 BOOLEAN,
1599 };
1601 public void visitIf(JCIf tree) {
1602 attribExpr(tree.cond, env, syms.booleanType);
1603 attribStat(tree.thenpart, env);
1604 if (tree.elsepart != null)
1605 attribStat(tree.elsepart, env);
1606 chk.checkEmptyIf(tree);
1607 result = null;
1608 }
1610 public void visitExec(JCExpressionStatement tree) {
1611 //a fresh environment is required for 292 inference to work properly ---
1612 //see Infer.instantiatePolymorphicSignatureInstance()
1613 Env<AttrContext> localEnv = env.dup(tree);
1614 attribExpr(tree.expr, localEnv);
1615 result = null;
1616 }
1618 public void visitBreak(JCBreak tree) {
1619 tree.target = findJumpTarget(tree.pos(), tree.getTag(), tree.label, env);
1620 result = null;
1621 }
1623 public void visitContinue(JCContinue tree) {
1624 tree.target = findJumpTarget(tree.pos(), tree.getTag(), tree.label, env);
1625 result = null;
1626 }
1627 //where
1628 /** Return the target of a break or continue statement, if it exists,
1629 * report an error if not.
1630 * Note: The target of a labelled break or continue is the
1631 * (non-labelled) statement tree referred to by the label,
1632 * not the tree representing the labelled statement itself.
1633 *
1634 * @param pos The position to be used for error diagnostics
1635 * @param tag The tag of the jump statement. This is either
1636 * Tree.BREAK or Tree.CONTINUE.
1637 * @param label The label of the jump statement, or null if no
1638 * label is given.
1639 * @param env The environment current at the jump statement.
1640 */
1641 private JCTree findJumpTarget(DiagnosticPosition pos,
1642 JCTree.Tag tag,
1643 Name label,
1644 Env<AttrContext> env) {
1645 // Search environments outwards from the point of jump.
1646 Env<AttrContext> env1 = env;
1647 LOOP:
1648 while (env1 != null) {
1649 switch (env1.tree.getTag()) {
1650 case LABELLED:
1651 JCLabeledStatement labelled = (JCLabeledStatement)env1.tree;
1652 if (label == labelled.label) {
1653 // If jump is a continue, check that target is a loop.
1654 if (tag == CONTINUE) {
1655 if (!labelled.body.hasTag(DOLOOP) &&
1656 !labelled.body.hasTag(WHILELOOP) &&
1657 !labelled.body.hasTag(FORLOOP) &&
1658 !labelled.body.hasTag(FOREACHLOOP))
1659 log.error(pos, "not.loop.label", label);
1660 // Found labelled statement target, now go inwards
1661 // to next non-labelled tree.
1662 return TreeInfo.referencedStatement(labelled);
1663 } else {
1664 return labelled;
1665 }
1666 }
1667 break;
1668 case DOLOOP:
1669 case WHILELOOP:
1670 case FORLOOP:
1671 case FOREACHLOOP:
1672 if (label == null) return env1.tree;
1673 break;
1674 case SWITCH:
1675 if (label == null && tag == BREAK) return env1.tree;
1676 break;
1677 case LAMBDA:
1678 case METHODDEF:
1679 case CLASSDEF:
1680 break LOOP;
1681 default:
1682 }
1683 env1 = env1.next;
1684 }
1685 if (label != null)
1686 log.error(pos, "undef.label", label);
1687 else if (tag == CONTINUE)
1688 log.error(pos, "cont.outside.loop");
1689 else
1690 log.error(pos, "break.outside.switch.loop");
1691 return null;
1692 }
1694 public void visitReturn(JCReturn tree) {
1695 // Check that there is an enclosing method which is
1696 // nested within than the enclosing class.
1697 if (env.info.returnResult == null) {
1698 log.error(tree.pos(), "ret.outside.meth");
1699 } else {
1700 // Attribute return expression, if it exists, and check that
1701 // it conforms to result type of enclosing method.
1702 if (tree.expr != null) {
1703 if (env.info.returnResult.pt.hasTag(VOID)) {
1704 env.info.returnResult.checkContext.report(tree.expr.pos(),
1705 diags.fragment("unexpected.ret.val"));
1706 }
1707 attribTree(tree.expr, env, env.info.returnResult);
1708 } else if (!env.info.returnResult.pt.hasTag(VOID) &&
1709 !env.info.returnResult.pt.hasTag(NONE)) {
1710 env.info.returnResult.checkContext.report(tree.pos(),
1711 diags.fragment("missing.ret.val"));
1712 }
1713 }
1714 result = null;
1715 }
1717 public void visitThrow(JCThrow tree) {
1718 Type owntype = attribExpr(tree.expr, env, allowPoly ? Type.noType : syms.throwableType);
1719 if (allowPoly) {
1720 chk.checkType(tree, owntype, syms.throwableType);
1721 }
1722 result = null;
1723 }
1725 public void visitAssert(JCAssert tree) {
1726 attribExpr(tree.cond, env, syms.booleanType);
1727 if (tree.detail != null) {
1728 chk.checkNonVoid(tree.detail.pos(), attribExpr(tree.detail, env));
1729 }
1730 result = null;
1731 }
1733 /** Visitor method for method invocations.
1734 * NOTE: The method part of an application will have in its type field
1735 * the return type of the method, not the method's type itself!
1736 */
1737 public void visitApply(JCMethodInvocation tree) {
1738 // The local environment of a method application is
1739 // a new environment nested in the current one.
1740 Env<AttrContext> localEnv = env.dup(tree, env.info.dup());
1742 // The types of the actual method arguments.
1743 List<Type> argtypes;
1745 // The types of the actual method type arguments.
1746 List<Type> typeargtypes = null;
1748 Name methName = TreeInfo.name(tree.meth);
1750 boolean isConstructorCall =
1751 methName == names._this || methName == names._super;
1753 ListBuffer<Type> argtypesBuf = new ListBuffer<>();
1754 if (isConstructorCall) {
1755 // We are seeing a ...this(...) or ...super(...) call.
1756 // Check that this is the first statement in a constructor.
1757 if (checkFirstConstructorStat(tree, env)) {
1759 // Record the fact
1760 // that this is a constructor call (using isSelfCall).
1761 localEnv.info.isSelfCall = true;
1763 // Attribute arguments, yielding list of argument types.
1764 attribArgs(tree.args, localEnv, argtypesBuf);
1765 argtypes = argtypesBuf.toList();
1766 typeargtypes = attribTypes(tree.typeargs, localEnv);
1768 // Variable `site' points to the class in which the called
1769 // constructor is defined.
1770 Type site = env.enclClass.sym.type;
1771 if (methName == names._super) {
1772 if (site == syms.objectType) {
1773 log.error(tree.meth.pos(), "no.superclass", site);
1774 site = types.createErrorType(syms.objectType);
1775 } else {
1776 site = types.supertype(site);
1777 }
1778 }
1780 if (site.hasTag(CLASS)) {
1781 Type encl = site.getEnclosingType();
1782 while (encl != null && encl.hasTag(TYPEVAR))
1783 encl = encl.getUpperBound();
1784 if (encl.hasTag(CLASS)) {
1785 // we are calling a nested class
1787 if (tree.meth.hasTag(SELECT)) {
1788 JCTree qualifier = ((JCFieldAccess) tree.meth).selected;
1790 // We are seeing a prefixed call, of the form
1791 // <expr>.super(...).
1792 // Check that the prefix expression conforms
1793 // to the outer instance type of the class.
1794 chk.checkRefType(qualifier.pos(),
1795 attribExpr(qualifier, localEnv,
1796 encl));
1797 } else if (methName == names._super) {
1798 // qualifier omitted; check for existence
1799 // of an appropriate implicit qualifier.
1800 rs.resolveImplicitThis(tree.meth.pos(),
1801 localEnv, site, true);
1802 }
1803 } else if (tree.meth.hasTag(SELECT)) {
1804 log.error(tree.meth.pos(), "illegal.qual.not.icls",
1805 site.tsym);
1806 }
1808 // if we're calling a java.lang.Enum constructor,
1809 // prefix the implicit String and int parameters
1810 if (site.tsym == syms.enumSym && allowEnums)
1811 argtypes = argtypes.prepend(syms.intType).prepend(syms.stringType);
1813 // Resolve the called constructor under the assumption
1814 // that we are referring to a superclass instance of the
1815 // current instance (JLS ???).
1816 boolean selectSuperPrev = localEnv.info.selectSuper;
1817 localEnv.info.selectSuper = true;
1818 localEnv.info.pendingResolutionPhase = null;
1819 Symbol sym = rs.resolveConstructor(
1820 tree.meth.pos(), localEnv, site, argtypes, typeargtypes);
1821 localEnv.info.selectSuper = selectSuperPrev;
1823 // Set method symbol to resolved constructor...
1824 TreeInfo.setSymbol(tree.meth, sym);
1826 // ...and check that it is legal in the current context.
1827 // (this will also set the tree's type)
1828 Type mpt = newMethodTemplate(resultInfo.pt, argtypes, typeargtypes);
1829 checkId(tree.meth, site, sym, localEnv, new ResultInfo(MTH, mpt));
1830 }
1831 // Otherwise, `site' is an error type and we do nothing
1832 }
1833 result = tree.type = syms.voidType;
1834 } else {
1835 // Otherwise, we are seeing a regular method call.
1836 // Attribute the arguments, yielding list of argument types, ...
1837 int kind = attribArgs(tree.args, localEnv, argtypesBuf);
1838 argtypes = argtypesBuf.toList();
1839 typeargtypes = attribAnyTypes(tree.typeargs, localEnv);
1841 // ... and attribute the method using as a prototype a methodtype
1842 // whose formal argument types is exactly the list of actual
1843 // arguments (this will also set the method symbol).
1844 Type mpt = newMethodTemplate(resultInfo.pt, argtypes, typeargtypes);
1845 localEnv.info.pendingResolutionPhase = null;
1846 Type mtype = attribTree(tree.meth, localEnv, new ResultInfo(kind, mpt, resultInfo.checkContext));
1848 // Compute the result type.
1849 Type restype = mtype.getReturnType();
1850 if (restype.hasTag(WILDCARD))
1851 throw new AssertionError(mtype);
1853 Type qualifier = (tree.meth.hasTag(SELECT))
1854 ? ((JCFieldAccess) tree.meth).selected.type
1855 : env.enclClass.sym.type;
1856 restype = adjustMethodReturnType(qualifier, methName, argtypes, restype);
1858 chk.checkRefTypes(tree.typeargs, typeargtypes);
1860 // Check that value of resulting type is admissible in the
1861 // current context. Also, capture the return type
1862 result = check(tree, capture(restype), VAL, resultInfo);
1863 }
1864 chk.validate(tree.typeargs, localEnv);
1865 }
1866 //where
1867 Type adjustMethodReturnType(Type qualifierType, Name methodName, List<Type> argtypes, Type restype) {
1868 if (allowCovariantReturns &&
1869 methodName == names.clone &&
1870 types.isArray(qualifierType)) {
1871 // as a special case, array.clone() has a result that is
1872 // the same as static type of the array being cloned
1873 return qualifierType;
1874 } else if (allowGenerics &&
1875 methodName == names.getClass &&
1876 argtypes.isEmpty()) {
1877 // as a special case, x.getClass() has type Class<? extends |X|>
1878 return new ClassType(restype.getEnclosingType(),
1879 List.<Type>of(new WildcardType(types.erasure(qualifierType),
1880 BoundKind.EXTENDS,
1881 syms.boundClass)),
1882 restype.tsym);
1883 } else {
1884 return restype;
1885 }
1886 }
1888 /** Check that given application node appears as first statement
1889 * in a constructor call.
1890 * @param tree The application node
1891 * @param env The environment current at the application.
1892 */
1893 boolean checkFirstConstructorStat(JCMethodInvocation tree, Env<AttrContext> env) {
1894 JCMethodDecl enclMethod = env.enclMethod;
1895 if (enclMethod != null && enclMethod.name == names.init) {
1896 JCBlock body = enclMethod.body;
1897 if (body.stats.head.hasTag(EXEC) &&
1898 ((JCExpressionStatement) body.stats.head).expr == tree)
1899 return true;
1900 }
1901 log.error(tree.pos(),"call.must.be.first.stmt.in.ctor",
1902 TreeInfo.name(tree.meth));
1903 return false;
1904 }
1906 /** Obtain a method type with given argument types.
1907 */
1908 Type newMethodTemplate(Type restype, List<Type> argtypes, List<Type> typeargtypes) {
1909 MethodType mt = new MethodType(argtypes, restype, List.<Type>nil(), syms.methodClass);
1910 return (typeargtypes == null) ? mt : (Type)new ForAll(typeargtypes, mt);
1911 }
1913 public void visitNewClass(final JCNewClass tree) {
1914 Type owntype = types.createErrorType(tree.type);
1916 // The local environment of a class creation is
1917 // a new environment nested in the current one.
1918 Env<AttrContext> localEnv = env.dup(tree, env.info.dup());
1920 // The anonymous inner class definition of the new expression,
1921 // if one is defined by it.
1922 JCClassDecl cdef = tree.def;
1924 // If enclosing class is given, attribute it, and
1925 // complete class name to be fully qualified
1926 JCExpression clazz = tree.clazz; // Class field following new
1927 JCExpression clazzid; // Identifier in class field
1928 JCAnnotatedType annoclazzid; // Annotated type enclosing clazzid
1929 annoclazzid = null;
1931 if (clazz.hasTag(TYPEAPPLY)) {
1932 clazzid = ((JCTypeApply) clazz).clazz;
1933 if (clazzid.hasTag(ANNOTATED_TYPE)) {
1934 annoclazzid = (JCAnnotatedType) clazzid;
1935 clazzid = annoclazzid.underlyingType;
1936 }
1937 } else {
1938 if (clazz.hasTag(ANNOTATED_TYPE)) {
1939 annoclazzid = (JCAnnotatedType) clazz;
1940 clazzid = annoclazzid.underlyingType;
1941 } else {
1942 clazzid = clazz;
1943 }
1944 }
1946 JCExpression clazzid1 = clazzid; // The same in fully qualified form
1948 if (tree.encl != null) {
1949 // We are seeing a qualified new, of the form
1950 // <expr>.new C <...> (...) ...
1951 // In this case, we let clazz stand for the name of the
1952 // allocated class C prefixed with the type of the qualifier
1953 // expression, so that we can
1954 // resolve it with standard techniques later. I.e., if
1955 // <expr> has type T, then <expr>.new C <...> (...)
1956 // yields a clazz T.C.
1957 Type encltype = chk.checkRefType(tree.encl.pos(),
1958 attribExpr(tree.encl, env));
1959 // TODO 308: in <expr>.new C, do we also want to add the type annotations
1960 // from expr to the combined type, or not? Yes, do this.
1961 clazzid1 = make.at(clazz.pos).Select(make.Type(encltype),
1962 ((JCIdent) clazzid).name);
1964 EndPosTable endPosTable = this.env.toplevel.endPositions;
1965 endPosTable.storeEnd(clazzid1, tree.getEndPosition(endPosTable));
1966 if (clazz.hasTag(ANNOTATED_TYPE)) {
1967 JCAnnotatedType annoType = (JCAnnotatedType) clazz;
1968 List<JCAnnotation> annos = annoType.annotations;
1970 if (annoType.underlyingType.hasTag(TYPEAPPLY)) {
1971 clazzid1 = make.at(tree.pos).
1972 TypeApply(clazzid1,
1973 ((JCTypeApply) clazz).arguments);
1974 }
1976 clazzid1 = make.at(tree.pos).
1977 AnnotatedType(annos, clazzid1);
1978 } else if (clazz.hasTag(TYPEAPPLY)) {
1979 clazzid1 = make.at(tree.pos).
1980 TypeApply(clazzid1,
1981 ((JCTypeApply) clazz).arguments);
1982 }
1984 clazz = clazzid1;
1985 }
1987 // Attribute clazz expression and store
1988 // symbol + type back into the attributed tree.
1989 Type clazztype = TreeInfo.isEnumInit(env.tree) ?
1990 attribIdentAsEnumType(env, (JCIdent)clazz) :
1991 attribType(clazz, env);
1993 clazztype = chk.checkDiamond(tree, clazztype);
1994 chk.validate(clazz, localEnv);
1995 if (tree.encl != null) {
1996 // We have to work in this case to store
1997 // symbol + type back into the attributed tree.
1998 tree.clazz.type = clazztype;
1999 TreeInfo.setSymbol(clazzid, TreeInfo.symbol(clazzid1));
2000 clazzid.type = ((JCIdent) clazzid).sym.type;
2001 if (annoclazzid != null) {
2002 annoclazzid.type = clazzid.type;
2003 }
2004 if (!clazztype.isErroneous()) {
2005 if (cdef != null && clazztype.tsym.isInterface()) {
2006 log.error(tree.encl.pos(), "anon.class.impl.intf.no.qual.for.new");
2007 } else if (clazztype.tsym.isStatic()) {
2008 log.error(tree.encl.pos(), "qualified.new.of.static.class", clazztype.tsym);
2009 }
2010 }
2011 } else if (!clazztype.tsym.isInterface() &&
2012 clazztype.getEnclosingType().hasTag(CLASS)) {
2013 // Check for the existence of an apropos outer instance
2014 rs.resolveImplicitThis(tree.pos(), env, clazztype);
2015 }
2017 // Attribute constructor arguments.
2018 ListBuffer<Type> argtypesBuf = new ListBuffer<>();
2019 int pkind = attribArgs(tree.args, localEnv, argtypesBuf);
2020 List<Type> argtypes = argtypesBuf.toList();
2021 List<Type> typeargtypes = attribTypes(tree.typeargs, localEnv);
2023 // If we have made no mistakes in the class type...
2024 if (clazztype.hasTag(CLASS)) {
2025 // Enums may not be instantiated except implicitly
2026 if (allowEnums &&
2027 (clazztype.tsym.flags_field&Flags.ENUM) != 0 &&
2028 (!env.tree.hasTag(VARDEF) ||
2029 (((JCVariableDecl) env.tree).mods.flags&Flags.ENUM) == 0 ||
2030 ((JCVariableDecl) env.tree).init != tree))
2031 log.error(tree.pos(), "enum.cant.be.instantiated");
2032 // Check that class is not abstract
2033 if (cdef == null &&
2034 (clazztype.tsym.flags() & (ABSTRACT | INTERFACE)) != 0) {
2035 log.error(tree.pos(), "abstract.cant.be.instantiated",
2036 clazztype.tsym);
2037 } else if (cdef != null && clazztype.tsym.isInterface()) {
2038 // Check that no constructor arguments are given to
2039 // anonymous classes implementing an interface
2040 if (!argtypes.isEmpty())
2041 log.error(tree.args.head.pos(), "anon.class.impl.intf.no.args");
2043 if (!typeargtypes.isEmpty())
2044 log.error(tree.typeargs.head.pos(), "anon.class.impl.intf.no.typeargs");
2046 // Error recovery: pretend no arguments were supplied.
2047 argtypes = List.nil();
2048 typeargtypes = List.nil();
2049 } else if (TreeInfo.isDiamond(tree)) {
2050 ClassType site = new ClassType(clazztype.getEnclosingType(),
2051 clazztype.tsym.type.getTypeArguments(),
2052 clazztype.tsym);
2054 Env<AttrContext> diamondEnv = localEnv.dup(tree);
2055 diamondEnv.info.selectSuper = cdef != null;
2056 diamondEnv.info.pendingResolutionPhase = null;
2058 //if the type of the instance creation expression is a class type
2059 //apply method resolution inference (JLS 15.12.2.7). The return type
2060 //of the resolved constructor will be a partially instantiated type
2061 Symbol constructor = rs.resolveDiamond(tree.pos(),
2062 diamondEnv,
2063 site,
2064 argtypes,
2065 typeargtypes);
2066 tree.constructor = constructor.baseSymbol();
2068 final TypeSymbol csym = clazztype.tsym;
2069 ResultInfo diamondResult = new ResultInfo(MTH, newMethodTemplate(resultInfo.pt, argtypes, typeargtypes), new Check.NestedCheckContext(resultInfo.checkContext) {
2070 @Override
2071 public void report(DiagnosticPosition _unused, JCDiagnostic details) {
2072 enclosingContext.report(tree.clazz,
2073 diags.fragment("cant.apply.diamond.1", diags.fragment("diamond", csym), details));
2074 }
2075 });
2076 Type constructorType = tree.constructorType = types.createErrorType(clazztype);
2077 constructorType = checkId(tree, site,
2078 constructor,
2079 diamondEnv,
2080 diamondResult);
2082 tree.clazz.type = types.createErrorType(clazztype);
2083 if (!constructorType.isErroneous()) {
2084 tree.clazz.type = clazztype = constructorType.getReturnType();
2085 tree.constructorType = types.createMethodTypeWithReturn(constructorType, syms.voidType);
2086 }
2087 clazztype = chk.checkClassType(tree.clazz, tree.clazz.type, true);
2088 }
2090 // Resolve the called constructor under the assumption
2091 // that we are referring to a superclass instance of the
2092 // current instance (JLS ???).
2093 else {
2094 //the following code alters some of the fields in the current
2095 //AttrContext - hence, the current context must be dup'ed in
2096 //order to avoid downstream failures
2097 Env<AttrContext> rsEnv = localEnv.dup(tree);
2098 rsEnv.info.selectSuper = cdef != null;
2099 rsEnv.info.pendingResolutionPhase = null;
2100 tree.constructor = rs.resolveConstructor(
2101 tree.pos(), rsEnv, clazztype, argtypes, typeargtypes);
2102 if (cdef == null) { //do not check twice!
2103 tree.constructorType = checkId(tree,
2104 clazztype,
2105 tree.constructor,
2106 rsEnv,
2107 new ResultInfo(pkind, newMethodTemplate(syms.voidType, argtypes, typeargtypes)));
2108 if (rsEnv.info.lastResolveVarargs())
2109 Assert.check(tree.constructorType.isErroneous() || tree.varargsElement != null);
2110 }
2111 if (cdef == null &&
2112 !clazztype.isErroneous() &&
2113 clazztype.getTypeArguments().nonEmpty() &&
2114 findDiamonds) {
2115 findDiamond(localEnv, tree, clazztype);
2116 }
2117 }
2119 if (cdef != null) {
2120 // We are seeing an anonymous class instance creation.
2121 // In this case, the class instance creation
2122 // expression
2123 //
2124 // E.new <typeargs1>C<typargs2>(args) { ... }
2125 //
2126 // is represented internally as
2127 //
2128 // E . new <typeargs1>C<typargs2>(args) ( class <empty-name> { ... } ) .
2129 //
2130 // This expression is then *transformed* as follows:
2131 //
2132 // (1) add a STATIC flag to the class definition
2133 // if the current environment is static
2134 // (2) add an extends or implements clause
2135 // (3) add a constructor.
2136 //
2137 // For instance, if C is a class, and ET is the type of E,
2138 // the expression
2139 //
2140 // E.new <typeargs1>C<typargs2>(args) { ... }
2141 //
2142 // is translated to (where X is a fresh name and typarams is the
2143 // parameter list of the super constructor):
2144 //
2145 // new <typeargs1>X(<*nullchk*>E, args) where
2146 // X extends C<typargs2> {
2147 // <typarams> X(ET e, args) {
2148 // e.<typeargs1>super(args)
2149 // }
2150 // ...
2151 // }
2152 if (Resolve.isStatic(env)) cdef.mods.flags |= STATIC;
2154 if (clazztype.tsym.isInterface()) {
2155 cdef.implementing = List.of(clazz);
2156 } else {
2157 cdef.extending = clazz;
2158 }
2160 attribStat(cdef, localEnv);
2162 checkLambdaCandidate(tree, cdef.sym, clazztype);
2164 // If an outer instance is given,
2165 // prefix it to the constructor arguments
2166 // and delete it from the new expression
2167 if (tree.encl != null && !clazztype.tsym.isInterface()) {
2168 tree.args = tree.args.prepend(makeNullCheck(tree.encl));
2169 argtypes = argtypes.prepend(tree.encl.type);
2170 tree.encl = null;
2171 }
2173 // Reassign clazztype and recompute constructor.
2174 clazztype = cdef.sym.type;
2175 Symbol sym = tree.constructor = rs.resolveConstructor(
2176 tree.pos(), localEnv, clazztype, argtypes, typeargtypes);
2177 Assert.check(sym.kind < AMBIGUOUS);
2178 tree.constructor = sym;
2179 tree.constructorType = checkId(tree,
2180 clazztype,
2181 tree.constructor,
2182 localEnv,
2183 new ResultInfo(pkind, newMethodTemplate(syms.voidType, argtypes, typeargtypes)));
2184 } else {
2185 if (tree.clazz.hasTag(ANNOTATED_TYPE)) {
2186 checkForDeclarationAnnotations(((JCAnnotatedType) tree.clazz).annotations,
2187 tree.clazz.type.tsym);
2188 }
2189 }
2191 if (tree.constructor != null && tree.constructor.kind == MTH)
2192 owntype = clazztype;
2193 }
2194 result = check(tree, owntype, VAL, resultInfo);
2195 chk.validate(tree.typeargs, localEnv);
2196 }
2197 //where
2198 void findDiamond(Env<AttrContext> env, JCNewClass tree, Type clazztype) {
2199 JCTypeApply ta = (JCTypeApply)tree.clazz;
2200 List<JCExpression> prevTypeargs = ta.arguments;
2201 try {
2202 //create a 'fake' diamond AST node by removing type-argument trees
2203 ta.arguments = List.nil();
2204 ResultInfo findDiamondResult = new ResultInfo(VAL,
2205 resultInfo.checkContext.inferenceContext().free(resultInfo.pt) ? Type.noType : pt());
2206 Type inferred = deferredAttr.attribSpeculative(tree, env, findDiamondResult).type;
2207 Type polyPt = allowPoly ?
2208 syms.objectType :
2209 clazztype;
2210 if (!inferred.isErroneous() &&
2211 (allowPoly && pt() == Infer.anyPoly ?
2212 types.isSameType(inferred, clazztype) :
2213 types.isAssignable(inferred, pt().hasTag(NONE) ? polyPt : pt(), types.noWarnings))) {
2214 String key = types.isSameType(clazztype, inferred) ?
2215 "diamond.redundant.args" :
2216 "diamond.redundant.args.1";
2217 log.warning(tree.clazz.pos(), key, clazztype, inferred);
2218 }
2219 } finally {
2220 ta.arguments = prevTypeargs;
2221 }
2222 }
2224 private void checkLambdaCandidate(JCNewClass tree, ClassSymbol csym, Type clazztype) {
2225 if (allowLambda &&
2226 identifyLambdaCandidate &&
2227 clazztype.hasTag(CLASS) &&
2228 !pt().hasTag(NONE) &&
2229 types.isFunctionalInterface(clazztype.tsym)) {
2230 Symbol descriptor = types.findDescriptorSymbol(clazztype.tsym);
2231 int count = 0;
2232 boolean found = false;
2233 for (Symbol sym : csym.members().getElements()) {
2234 if ((sym.flags() & SYNTHETIC) != 0 ||
2235 sym.isConstructor()) continue;
2236 count++;
2237 if (sym.kind != MTH ||
2238 !sym.name.equals(descriptor.name)) continue;
2239 Type mtype = types.memberType(clazztype, sym);
2240 if (types.overrideEquivalent(mtype, types.memberType(clazztype, descriptor))) {
2241 found = true;
2242 }
2243 }
2244 if (found && count == 1) {
2245 log.note(tree.def, "potential.lambda.found");
2246 }
2247 }
2248 }
2250 private void checkForDeclarationAnnotations(List<? extends JCAnnotation> annotations,
2251 Symbol sym) {
2252 // Ensure that no declaration annotations are present.
2253 // Note that a tree type might be an AnnotatedType with
2254 // empty annotations, if only declaration annotations were given.
2255 // This method will raise an error for such a type.
2256 for (JCAnnotation ai : annotations) {
2257 if (typeAnnotations.annotationType(ai.attribute, sym) == TypeAnnotations.AnnotationType.DECLARATION) {
2258 log.error(ai.pos(), "annotation.type.not.applicable");
2259 }
2260 }
2261 }
2264 /** Make an attributed null check tree.
2265 */
2266 public JCExpression makeNullCheck(JCExpression arg) {
2267 // optimization: X.this is never null; skip null check
2268 Name name = TreeInfo.name(arg);
2269 if (name == names._this || name == names._super) return arg;
2271 JCTree.Tag optag = NULLCHK;
2272 JCUnary tree = make.at(arg.pos).Unary(optag, arg);
2273 tree.operator = syms.nullcheck;
2274 tree.type = arg.type;
2275 return tree;
2276 }
2278 public void visitNewArray(JCNewArray tree) {
2279 Type owntype = types.createErrorType(tree.type);
2280 Env<AttrContext> localEnv = env.dup(tree);
2281 Type elemtype;
2282 if (tree.elemtype != null) {
2283 elemtype = attribType(tree.elemtype, localEnv);
2284 chk.validate(tree.elemtype, localEnv);
2285 owntype = elemtype;
2286 for (List<JCExpression> l = tree.dims; l.nonEmpty(); l = l.tail) {
2287 attribExpr(l.head, localEnv, syms.intType);
2288 owntype = new ArrayType(owntype, syms.arrayClass);
2289 }
2290 if (tree.elemtype.hasTag(ANNOTATED_TYPE)) {
2291 checkForDeclarationAnnotations(((JCAnnotatedType) tree.elemtype).annotations,
2292 tree.elemtype.type.tsym);
2293 }
2294 } else {
2295 // we are seeing an untyped aggregate { ... }
2296 // this is allowed only if the prototype is an array
2297 if (pt().hasTag(ARRAY)) {
2298 elemtype = types.elemtype(pt());
2299 } else {
2300 if (!pt().hasTag(ERROR)) {
2301 log.error(tree.pos(), "illegal.initializer.for.type",
2302 pt());
2303 }
2304 elemtype = types.createErrorType(pt());
2305 }
2306 }
2307 if (tree.elems != null) {
2308 attribExprs(tree.elems, localEnv, elemtype);
2309 owntype = new ArrayType(elemtype, syms.arrayClass);
2310 }
2311 if (!types.isReifiable(elemtype))
2312 log.error(tree.pos(), "generic.array.creation");
2313 result = check(tree, owntype, VAL, resultInfo);
2314 }
2316 /*
2317 * A lambda expression can only be attributed when a target-type is available.
2318 * In addition, if the target-type is that of a functional interface whose
2319 * descriptor contains inference variables in argument position the lambda expression
2320 * is 'stuck' (see DeferredAttr).
2321 */
2322 @Override
2323 public void visitLambda(final JCLambda that) {
2324 if (pt().isErroneous() || (pt().hasTag(NONE) && pt() != Type.recoveryType)) {
2325 if (pt().hasTag(NONE)) {
2326 //lambda only allowed in assignment or method invocation/cast context
2327 log.error(that.pos(), "unexpected.lambda");
2328 }
2329 result = that.type = types.createErrorType(pt());
2330 return;
2331 }
2332 //create an environment for attribution of the lambda expression
2333 final Env<AttrContext> localEnv = lambdaEnv(that, env);
2334 boolean needsRecovery =
2335 resultInfo.checkContext.deferredAttrContext().mode == DeferredAttr.AttrMode.CHECK;
2336 try {
2337 Type currentTarget = pt();
2338 List<Type> explicitParamTypes = null;
2339 if (that.paramKind == JCLambda.ParameterKind.EXPLICIT) {
2340 //attribute lambda parameters
2341 attribStats(that.params, localEnv);
2342 explicitParamTypes = TreeInfo.types(that.params);
2343 }
2345 Type lambdaType;
2346 if (pt() != Type.recoveryType) {
2347 /* We need to adjust the target. If the target is an
2348 * intersection type, for example: SAM & I1 & I2 ...
2349 * the target will be updated to SAM
2350 */
2351 currentTarget = targetChecker.visit(currentTarget, that);
2352 if (explicitParamTypes != null) {
2353 currentTarget = infer.instantiateFunctionalInterface(that,
2354 currentTarget, explicitParamTypes, resultInfo.checkContext);
2355 }
2356 lambdaType = types.findDescriptorType(currentTarget);
2357 } else {
2358 currentTarget = Type.recoveryType;
2359 lambdaType = fallbackDescriptorType(that);
2360 }
2362 setFunctionalInfo(localEnv, that, pt(), lambdaType, currentTarget, resultInfo.checkContext);
2364 if (lambdaType.hasTag(FORALL)) {
2365 //lambda expression target desc cannot be a generic method
2366 resultInfo.checkContext.report(that, diags.fragment("invalid.generic.lambda.target",
2367 lambdaType, kindName(currentTarget.tsym), currentTarget.tsym));
2368 result = that.type = types.createErrorType(pt());
2369 return;
2370 }
2372 if (that.paramKind == JCLambda.ParameterKind.IMPLICIT) {
2373 //add param type info in the AST
2374 List<Type> actuals = lambdaType.getParameterTypes();
2375 List<JCVariableDecl> params = that.params;
2377 boolean arityMismatch = false;
2379 while (params.nonEmpty()) {
2380 if (actuals.isEmpty()) {
2381 //not enough actuals to perform lambda parameter inference
2382 arityMismatch = true;
2383 }
2384 //reset previously set info
2385 Type argType = arityMismatch ?
2386 syms.errType :
2387 actuals.head;
2388 params.head.vartype = make.at(params.head).Type(argType);
2389 params.head.sym = null;
2390 actuals = actuals.isEmpty() ?
2391 actuals :
2392 actuals.tail;
2393 params = params.tail;
2394 }
2396 //attribute lambda parameters
2397 attribStats(that.params, localEnv);
2399 if (arityMismatch) {
2400 resultInfo.checkContext.report(that, diags.fragment("incompatible.arg.types.in.lambda"));
2401 result = that.type = types.createErrorType(currentTarget);
2402 return;
2403 }
2404 }
2406 //from this point on, no recovery is needed; if we are in assignment context
2407 //we will be able to attribute the whole lambda body, regardless of errors;
2408 //if we are in a 'check' method context, and the lambda is not compatible
2409 //with the target-type, it will be recovered anyway in Attr.checkId
2410 needsRecovery = false;
2412 FunctionalReturnContext funcContext = that.getBodyKind() == JCLambda.BodyKind.EXPRESSION ?
2413 new ExpressionLambdaReturnContext((JCExpression)that.getBody(), resultInfo.checkContext) :
2414 new FunctionalReturnContext(resultInfo.checkContext);
2416 ResultInfo bodyResultInfo = lambdaType.getReturnType() == Type.recoveryType ?
2417 recoveryInfo :
2418 new ResultInfo(VAL, lambdaType.getReturnType(), funcContext);
2419 localEnv.info.returnResult = bodyResultInfo;
2421 if (that.getBodyKind() == JCLambda.BodyKind.EXPRESSION) {
2422 attribTree(that.getBody(), localEnv, bodyResultInfo);
2423 } else {
2424 JCBlock body = (JCBlock)that.body;
2425 attribStats(body.stats, localEnv);
2426 }
2428 result = check(that, currentTarget, VAL, resultInfo);
2430 boolean isSpeculativeRound =
2431 resultInfo.checkContext.deferredAttrContext().mode == DeferredAttr.AttrMode.SPECULATIVE;
2433 preFlow(that);
2434 flow.analyzeLambda(env, that, make, isSpeculativeRound);
2436 checkLambdaCompatible(that, lambdaType, resultInfo.checkContext);
2438 if (!isSpeculativeRound) {
2439 //add thrown types as bounds to the thrown types free variables if needed:
2440 if (resultInfo.checkContext.inferenceContext().free(lambdaType.getThrownTypes())) {
2441 List<Type> inferredThrownTypes = flow.analyzeLambdaThrownTypes(env, that, make);
2442 List<Type> thrownTypes = resultInfo.checkContext.inferenceContext().asFree(lambdaType.getThrownTypes());
2444 chk.unhandled(inferredThrownTypes, thrownTypes);
2445 }
2447 checkAccessibleTypes(that, localEnv, resultInfo.checkContext.inferenceContext(), lambdaType, currentTarget);
2448 }
2449 result = check(that, currentTarget, VAL, resultInfo);
2450 } catch (Types.FunctionDescriptorLookupError ex) {
2451 JCDiagnostic cause = ex.getDiagnostic();
2452 resultInfo.checkContext.report(that, cause);
2453 result = that.type = types.createErrorType(pt());
2454 return;
2455 } finally {
2456 localEnv.info.scope.leave();
2457 if (needsRecovery) {
2458 attribTree(that, env, recoveryInfo);
2459 }
2460 }
2461 }
2462 //where
2463 void preFlow(JCLambda tree) {
2464 new PostAttrAnalyzer() {
2465 @Override
2466 public void scan(JCTree tree) {
2467 if (tree == null ||
2468 (tree.type != null &&
2469 tree.type == Type.stuckType)) {
2470 //don't touch stuck expressions!
2471 return;
2472 }
2473 super.scan(tree);
2474 }
2475 }.scan(tree);
2476 }
2478 Types.MapVisitor<DiagnosticPosition> targetChecker = new Types.MapVisitor<DiagnosticPosition>() {
2480 @Override
2481 public Type visitClassType(ClassType t, DiagnosticPosition pos) {
2482 return t.isCompound() ?
2483 visitIntersectionClassType((IntersectionClassType)t, pos) : t;
2484 }
2486 public Type visitIntersectionClassType(IntersectionClassType ict, DiagnosticPosition pos) {
2487 Symbol desc = types.findDescriptorSymbol(makeNotionalInterface(ict));
2488 Type target = null;
2489 for (Type bound : ict.getExplicitComponents()) {
2490 TypeSymbol boundSym = bound.tsym;
2491 if (types.isFunctionalInterface(boundSym) &&
2492 types.findDescriptorSymbol(boundSym) == desc) {
2493 target = bound;
2494 } else if (!boundSym.isInterface() || (boundSym.flags() & ANNOTATION) != 0) {
2495 //bound must be an interface
2496 reportIntersectionError(pos, "not.an.intf.component", boundSym);
2497 }
2498 }
2499 return target != null ?
2500 target :
2501 ict.getExplicitComponents().head; //error recovery
2502 }
2504 private TypeSymbol makeNotionalInterface(IntersectionClassType ict) {
2505 ListBuffer<Type> targs = new ListBuffer<>();
2506 ListBuffer<Type> supertypes = new ListBuffer<>();
2507 for (Type i : ict.interfaces_field) {
2508 if (i.isParameterized()) {
2509 targs.appendList(i.tsym.type.allparams());
2510 }
2511 supertypes.append(i.tsym.type);
2512 }
2513 IntersectionClassType notionalIntf =
2514 (IntersectionClassType)types.makeCompoundType(supertypes.toList());
2515 notionalIntf.allparams_field = targs.toList();
2516 notionalIntf.tsym.flags_field |= INTERFACE;
2517 return notionalIntf.tsym;
2518 }
2520 private void reportIntersectionError(DiagnosticPosition pos, String key, Object... args) {
2521 resultInfo.checkContext.report(pos, diags.fragment("bad.intersection.target.for.functional.expr",
2522 diags.fragment(key, args)));
2523 }
2524 };
2526 private Type fallbackDescriptorType(JCExpression tree) {
2527 switch (tree.getTag()) {
2528 case LAMBDA:
2529 JCLambda lambda = (JCLambda)tree;
2530 List<Type> argtypes = List.nil();
2531 for (JCVariableDecl param : lambda.params) {
2532 argtypes = param.vartype != null ?
2533 argtypes.append(param.vartype.type) :
2534 argtypes.append(syms.errType);
2535 }
2536 return new MethodType(argtypes, Type.recoveryType,
2537 List.of(syms.throwableType), syms.methodClass);
2538 case REFERENCE:
2539 return new MethodType(List.<Type>nil(), Type.recoveryType,
2540 List.of(syms.throwableType), syms.methodClass);
2541 default:
2542 Assert.error("Cannot get here!");
2543 }
2544 return null;
2545 }
2547 private void checkAccessibleTypes(final DiagnosticPosition pos, final Env<AttrContext> env,
2548 final InferenceContext inferenceContext, final Type... ts) {
2549 checkAccessibleTypes(pos, env, inferenceContext, List.from(ts));
2550 }
2552 private void checkAccessibleTypes(final DiagnosticPosition pos, final Env<AttrContext> env,
2553 final InferenceContext inferenceContext, final List<Type> ts) {
2554 if (inferenceContext.free(ts)) {
2555 inferenceContext.addFreeTypeListener(ts, new FreeTypeListener() {
2556 @Override
2557 public void typesInferred(InferenceContext inferenceContext) {
2558 checkAccessibleTypes(pos, env, inferenceContext, inferenceContext.asInstTypes(ts));
2559 }
2560 });
2561 } else {
2562 for (Type t : ts) {
2563 rs.checkAccessibleType(env, t);
2564 }
2565 }
2566 }
2568 /**
2569 * Lambda/method reference have a special check context that ensures
2570 * that i.e. a lambda return type is compatible with the expected
2571 * type according to both the inherited context and the assignment
2572 * context.
2573 */
2574 class FunctionalReturnContext extends Check.NestedCheckContext {
2576 FunctionalReturnContext(CheckContext enclosingContext) {
2577 super(enclosingContext);
2578 }
2580 @Override
2581 public boolean compatible(Type found, Type req, Warner warn) {
2582 //return type must be compatible in both current context and assignment context
2583 return chk.basicHandler.compatible(found, inferenceContext().asFree(req), warn);
2584 }
2586 @Override
2587 public void report(DiagnosticPosition pos, JCDiagnostic details) {
2588 enclosingContext.report(pos, diags.fragment("incompatible.ret.type.in.lambda", details));
2589 }
2590 }
2592 class ExpressionLambdaReturnContext extends FunctionalReturnContext {
2594 JCExpression expr;
2596 ExpressionLambdaReturnContext(JCExpression expr, CheckContext enclosingContext) {
2597 super(enclosingContext);
2598 this.expr = expr;
2599 }
2601 @Override
2602 public boolean compatible(Type found, Type req, Warner warn) {
2603 //a void return is compatible with an expression statement lambda
2604 return TreeInfo.isExpressionStatement(expr) && req.hasTag(VOID) ||
2605 super.compatible(found, req, warn);
2606 }
2607 }
2609 /**
2610 * Lambda compatibility. Check that given return types, thrown types, parameter types
2611 * are compatible with the expected functional interface descriptor. This means that:
2612 * (i) parameter types must be identical to those of the target descriptor; (ii) return
2613 * types must be compatible with the return type of the expected descriptor.
2614 */
2615 private void checkLambdaCompatible(JCLambda tree, Type descriptor, CheckContext checkContext) {
2616 Type returnType = checkContext.inferenceContext().asFree(descriptor.getReturnType());
2618 //return values have already been checked - but if lambda has no return
2619 //values, we must ensure that void/value compatibility is correct;
2620 //this amounts at checking that, if a lambda body can complete normally,
2621 //the descriptor's return type must be void
2622 if (tree.getBodyKind() == JCLambda.BodyKind.STATEMENT && tree.canCompleteNormally &&
2623 !returnType.hasTag(VOID) && returnType != Type.recoveryType) {
2624 checkContext.report(tree, diags.fragment("incompatible.ret.type.in.lambda",
2625 diags.fragment("missing.ret.val", returnType)));
2626 }
2628 List<Type> argTypes = checkContext.inferenceContext().asFree(descriptor.getParameterTypes());
2629 if (!types.isSameTypes(argTypes, TreeInfo.types(tree.params))) {
2630 checkContext.report(tree, diags.fragment("incompatible.arg.types.in.lambda"));
2631 }
2632 }
2634 private Env<AttrContext> lambdaEnv(JCLambda that, Env<AttrContext> env) {
2635 Env<AttrContext> lambdaEnv;
2636 Symbol owner = env.info.scope.owner;
2637 if (owner.kind == VAR && owner.owner.kind == TYP) {
2638 //field initializer
2639 lambdaEnv = env.dup(that, env.info.dup(env.info.scope.dupUnshared()));
2640 lambdaEnv.info.scope.owner =
2641 new MethodSymbol((owner.flags() & STATIC) | BLOCK, names.empty, null,
2642 env.info.scope.owner);
2643 } else {
2644 lambdaEnv = env.dup(that, env.info.dup(env.info.scope.dup()));
2645 }
2646 return lambdaEnv;
2647 }
2649 @Override
2650 public void visitReference(final JCMemberReference that) {
2651 if (pt().isErroneous() || (pt().hasTag(NONE) && pt() != Type.recoveryType)) {
2652 if (pt().hasTag(NONE)) {
2653 //method reference only allowed in assignment or method invocation/cast context
2654 log.error(that.pos(), "unexpected.mref");
2655 }
2656 result = that.type = types.createErrorType(pt());
2657 return;
2658 }
2659 final Env<AttrContext> localEnv = env.dup(that);
2660 try {
2661 //attribute member reference qualifier - if this is a constructor
2662 //reference, the expected kind must be a type
2663 Type exprType = attribTree(that.expr, env, memberReferenceQualifierResult(that));
2665 if (that.getMode() == JCMemberReference.ReferenceMode.NEW) {
2666 exprType = chk.checkConstructorRefType(that.expr, exprType);
2667 if (!exprType.isErroneous() &&
2668 exprType.isRaw() &&
2669 that.typeargs != null) {
2670 log.error(that.expr.pos(), "invalid.mref", Kinds.kindName(that.getMode()),
2671 diags.fragment("mref.infer.and.explicit.params"));
2672 exprType = types.createErrorType(exprType);
2673 }
2674 }
2676 if (exprType.isErroneous()) {
2677 //if the qualifier expression contains problems,
2678 //give up attribution of method reference
2679 result = that.type = exprType;
2680 return;
2681 }
2683 if (TreeInfo.isStaticSelector(that.expr, names)) {
2684 //if the qualifier is a type, validate it; raw warning check is
2685 //omitted as we don't know at this stage as to whether this is a
2686 //raw selector (because of inference)
2687 chk.validate(that.expr, env, false);
2688 }
2690 //attrib type-arguments
2691 List<Type> typeargtypes = List.nil();
2692 if (that.typeargs != null) {
2693 typeargtypes = attribTypes(that.typeargs, localEnv);
2694 }
2696 Type target;
2697 Type desc;
2698 if (pt() != Type.recoveryType) {
2699 target = targetChecker.visit(pt(), that);
2700 desc = types.findDescriptorType(target);
2701 } else {
2702 target = Type.recoveryType;
2703 desc = fallbackDescriptorType(that);
2704 }
2706 setFunctionalInfo(localEnv, that, pt(), desc, target, resultInfo.checkContext);
2707 List<Type> argtypes = desc.getParameterTypes();
2708 Resolve.MethodCheck referenceCheck = rs.resolveMethodCheck;
2710 if (resultInfo.checkContext.inferenceContext().free(argtypes)) {
2711 referenceCheck = rs.new MethodReferenceCheck(resultInfo.checkContext.inferenceContext());
2712 }
2714 Pair<Symbol, Resolve.ReferenceLookupHelper> refResult = null;
2715 List<Type> saved_undet = resultInfo.checkContext.inferenceContext().save();
2716 try {
2717 refResult = rs.resolveMemberReference(that.pos(), localEnv, that, that.expr.type,
2718 that.name, argtypes, typeargtypes, true, referenceCheck,
2719 resultInfo.checkContext.inferenceContext());
2720 } finally {
2721 resultInfo.checkContext.inferenceContext().rollback(saved_undet);
2722 }
2724 Symbol refSym = refResult.fst;
2725 Resolve.ReferenceLookupHelper lookupHelper = refResult.snd;
2727 if (refSym.kind != MTH) {
2728 boolean targetError;
2729 switch (refSym.kind) {
2730 case ABSENT_MTH:
2731 targetError = false;
2732 break;
2733 case WRONG_MTH:
2734 case WRONG_MTHS:
2735 case AMBIGUOUS:
2736 case HIDDEN:
2737 case STATICERR:
2738 case MISSING_ENCL:
2739 targetError = true;
2740 break;
2741 default:
2742 Assert.error("unexpected result kind " + refSym.kind);
2743 targetError = false;
2744 }
2746 JCDiagnostic detailsDiag = ((Resolve.ResolveError)refSym).getDiagnostic(JCDiagnostic.DiagnosticType.FRAGMENT,
2747 that, exprType.tsym, exprType, that.name, argtypes, typeargtypes);
2749 JCDiagnostic.DiagnosticType diagKind = targetError ?
2750 JCDiagnostic.DiagnosticType.FRAGMENT : JCDiagnostic.DiagnosticType.ERROR;
2752 JCDiagnostic diag = diags.create(diagKind, log.currentSource(), that,
2753 "invalid.mref", Kinds.kindName(that.getMode()), detailsDiag);
2755 if (targetError && target == Type.recoveryType) {
2756 //a target error doesn't make sense during recovery stage
2757 //as we don't know what actual parameter types are
2758 result = that.type = target;
2759 return;
2760 } else {
2761 if (targetError) {
2762 resultInfo.checkContext.report(that, diag);
2763 } else {
2764 log.report(diag);
2765 }
2766 result = that.type = types.createErrorType(target);
2767 return;
2768 }
2769 }
2771 that.sym = refSym.baseSymbol();
2772 that.kind = lookupHelper.referenceKind(that.sym);
2773 that.ownerAccessible = rs.isAccessible(localEnv, that.sym.enclClass());
2775 if (desc.getReturnType() == Type.recoveryType) {
2776 // stop here
2777 result = that.type = target;
2778 return;
2779 }
2781 if (resultInfo.checkContext.deferredAttrContext().mode == AttrMode.CHECK) {
2783 if (that.getMode() == ReferenceMode.INVOKE &&
2784 TreeInfo.isStaticSelector(that.expr, names) &&
2785 that.kind.isUnbound() &&
2786 !desc.getParameterTypes().head.isParameterized()) {
2787 chk.checkRaw(that.expr, localEnv);
2788 }
2790 if (!that.kind.isUnbound() &&
2791 that.getMode() == ReferenceMode.INVOKE &&
2792 TreeInfo.isStaticSelector(that.expr, names) &&
2793 !that.sym.isStatic()) {
2794 log.error(that.expr.pos(), "invalid.mref", Kinds.kindName(that.getMode()),
2795 diags.fragment("non-static.cant.be.ref", Kinds.kindName(refSym), refSym));
2796 result = that.type = types.createErrorType(target);
2797 return;
2798 }
2800 if (that.kind.isUnbound() &&
2801 that.getMode() == ReferenceMode.INVOKE &&
2802 TreeInfo.isStaticSelector(that.expr, names) &&
2803 that.sym.isStatic()) {
2804 log.error(that.expr.pos(), "invalid.mref", Kinds.kindName(that.getMode()),
2805 diags.fragment("static.method.in.unbound.lookup", Kinds.kindName(refSym), refSym));
2806 result = that.type = types.createErrorType(target);
2807 return;
2808 }
2810 if (that.sym.isStatic() && TreeInfo.isStaticSelector(that.expr, names) &&
2811 exprType.getTypeArguments().nonEmpty()) {
2812 //static ref with class type-args
2813 log.error(that.expr.pos(), "invalid.mref", Kinds.kindName(that.getMode()),
2814 diags.fragment("static.mref.with.targs"));
2815 result = that.type = types.createErrorType(target);
2816 return;
2817 }
2819 if (that.sym.isStatic() && !TreeInfo.isStaticSelector(that.expr, names) &&
2820 !that.kind.isUnbound()) {
2821 //no static bound mrefs
2822 log.error(that.expr.pos(), "invalid.mref", Kinds.kindName(that.getMode()),
2823 diags.fragment("static.bound.mref"));
2824 result = that.type = types.createErrorType(target);
2825 return;
2826 }
2828 if (!refSym.isStatic() && that.kind == JCMemberReference.ReferenceKind.SUPER) {
2829 // Check that super-qualified symbols are not abstract (JLS)
2830 rs.checkNonAbstract(that.pos(), that.sym);
2831 }
2832 }
2834 ResultInfo checkInfo =
2835 resultInfo.dup(newMethodTemplate(
2836 desc.getReturnType().hasTag(VOID) ? Type.noType : desc.getReturnType(),
2837 that.kind.isUnbound() ? argtypes.tail : argtypes, typeargtypes));
2839 Type refType = checkId(that, lookupHelper.site, refSym, localEnv, checkInfo);
2841 if (that.kind.isUnbound() &&
2842 resultInfo.checkContext.inferenceContext().free(argtypes.head)) {
2843 //re-generate inference constraints for unbound receiver
2844 if (!types.isSubtype(resultInfo.checkContext.inferenceContext().asFree(argtypes.head), exprType)) {
2845 //cannot happen as this has already been checked - we just need
2846 //to regenerate the inference constraints, as that has been lost
2847 //as a result of the call to inferenceContext.save()
2848 Assert.error("Can't get here");
2849 }
2850 }
2852 if (!refType.isErroneous()) {
2853 refType = types.createMethodTypeWithReturn(refType,
2854 adjustMethodReturnType(lookupHelper.site, that.name, checkInfo.pt.getParameterTypes(), refType.getReturnType()));
2855 }
2857 //go ahead with standard method reference compatibility check - note that param check
2858 //is a no-op (as this has been taken care during method applicability)
2859 boolean isSpeculativeRound =
2860 resultInfo.checkContext.deferredAttrContext().mode == DeferredAttr.AttrMode.SPECULATIVE;
2861 checkReferenceCompatible(that, desc, refType, resultInfo.checkContext, isSpeculativeRound);
2862 if (!isSpeculativeRound) {
2863 checkAccessibleTypes(that, localEnv, resultInfo.checkContext.inferenceContext(), desc, target);
2864 }
2865 result = check(that, target, VAL, resultInfo);
2866 } catch (Types.FunctionDescriptorLookupError ex) {
2867 JCDiagnostic cause = ex.getDiagnostic();
2868 resultInfo.checkContext.report(that, cause);
2869 result = that.type = types.createErrorType(pt());
2870 return;
2871 }
2872 }
2873 //where
2874 ResultInfo memberReferenceQualifierResult(JCMemberReference tree) {
2875 //if this is a constructor reference, the expected kind must be a type
2876 return new ResultInfo(tree.getMode() == ReferenceMode.INVOKE ? VAL | TYP : TYP, Type.noType);
2877 }
2880 @SuppressWarnings("fallthrough")
2881 void checkReferenceCompatible(JCMemberReference tree, Type descriptor, Type refType, CheckContext checkContext, boolean speculativeAttr) {
2882 Type returnType = checkContext.inferenceContext().asFree(descriptor.getReturnType());
2884 Type resType;
2885 switch (tree.getMode()) {
2886 case NEW:
2887 if (!tree.expr.type.isRaw()) {
2888 resType = tree.expr.type;
2889 break;
2890 }
2891 default:
2892 resType = refType.getReturnType();
2893 }
2895 Type incompatibleReturnType = resType;
2897 if (returnType.hasTag(VOID)) {
2898 incompatibleReturnType = null;
2899 }
2901 if (!returnType.hasTag(VOID) && !resType.hasTag(VOID)) {
2902 if (resType.isErroneous() ||
2903 new FunctionalReturnContext(checkContext).compatible(resType, returnType, types.noWarnings)) {
2904 incompatibleReturnType = null;
2905 }
2906 }
2908 if (incompatibleReturnType != null) {
2909 checkContext.report(tree, diags.fragment("incompatible.ret.type.in.mref",
2910 diags.fragment("inconvertible.types", resType, descriptor.getReturnType())));
2911 }
2913 if (!speculativeAttr) {
2914 List<Type> thrownTypes = checkContext.inferenceContext().asFree(descriptor.getThrownTypes());
2915 if (chk.unhandled(refType.getThrownTypes(), thrownTypes).nonEmpty()) {
2916 log.error(tree, "incompatible.thrown.types.in.mref", refType.getThrownTypes());
2917 }
2918 }
2919 }
2921 /**
2922 * Set functional type info on the underlying AST. Note: as the target descriptor
2923 * might contain inference variables, we might need to register an hook in the
2924 * current inference context.
2925 */
2926 private void setFunctionalInfo(final Env<AttrContext> env, final JCFunctionalExpression fExpr,
2927 final Type pt, final Type descriptorType, final Type primaryTarget, final CheckContext checkContext) {
2928 if (checkContext.inferenceContext().free(descriptorType)) {
2929 checkContext.inferenceContext().addFreeTypeListener(List.of(pt, descriptorType), new FreeTypeListener() {
2930 public void typesInferred(InferenceContext inferenceContext) {
2931 setFunctionalInfo(env, fExpr, pt, inferenceContext.asInstType(descriptorType),
2932 inferenceContext.asInstType(primaryTarget), checkContext);
2933 }
2934 });
2935 } else {
2936 ListBuffer<Type> targets = new ListBuffer<>();
2937 if (pt.hasTag(CLASS)) {
2938 if (pt.isCompound()) {
2939 targets.append(types.removeWildcards(primaryTarget)); //this goes first
2940 for (Type t : ((IntersectionClassType)pt()).interfaces_field) {
2941 if (t != primaryTarget) {
2942 targets.append(types.removeWildcards(t));
2943 }
2944 }
2945 } else {
2946 targets.append(types.removeWildcards(primaryTarget));
2947 }
2948 }
2949 fExpr.targets = targets.toList();
2950 if (checkContext.deferredAttrContext().mode == DeferredAttr.AttrMode.CHECK &&
2951 pt != Type.recoveryType) {
2952 //check that functional interface class is well-formed
2953 ClassSymbol csym = types.makeFunctionalInterfaceClass(env,
2954 names.empty, List.of(fExpr.targets.head), ABSTRACT);
2955 if (csym != null) {
2956 chk.checkImplementations(env.tree, csym, csym);
2957 }
2958 }
2959 }
2960 }
2962 public void visitParens(JCParens tree) {
2963 Type owntype = attribTree(tree.expr, env, resultInfo);
2964 result = check(tree, owntype, pkind(), resultInfo);
2965 Symbol sym = TreeInfo.symbol(tree);
2966 if (sym != null && (sym.kind&(TYP|PCK)) != 0)
2967 log.error(tree.pos(), "illegal.start.of.type");
2968 }
2970 public void visitAssign(JCAssign tree) {
2971 Type owntype = attribTree(tree.lhs, env.dup(tree), varInfo);
2972 Type capturedType = capture(owntype);
2973 attribExpr(tree.rhs, env, owntype);
2974 result = check(tree, capturedType, VAL, resultInfo);
2975 }
2977 public void visitAssignop(JCAssignOp tree) {
2978 // Attribute arguments.
2979 Type owntype = attribTree(tree.lhs, env, varInfo);
2980 Type operand = attribExpr(tree.rhs, env);
2981 // Find operator.
2982 Symbol operator = tree.operator = rs.resolveBinaryOperator(
2983 tree.pos(), tree.getTag().noAssignOp(), env,
2984 owntype, operand);
2986 if (operator.kind == MTH &&
2987 !owntype.isErroneous() &&
2988 !operand.isErroneous()) {
2989 chk.checkOperator(tree.pos(),
2990 (OperatorSymbol)operator,
2991 tree.getTag().noAssignOp(),
2992 owntype,
2993 operand);
2994 chk.checkDivZero(tree.rhs.pos(), operator, operand);
2995 chk.checkCastable(tree.rhs.pos(),
2996 operator.type.getReturnType(),
2997 owntype);
2998 }
2999 result = check(tree, owntype, VAL, resultInfo);
3000 }
3002 public void visitUnary(JCUnary tree) {
3003 // Attribute arguments.
3004 Type argtype = (tree.getTag().isIncOrDecUnaryOp())
3005 ? attribTree(tree.arg, env, varInfo)
3006 : chk.checkNonVoid(tree.arg.pos(), attribExpr(tree.arg, env));
3008 // Find operator.
3009 Symbol operator = tree.operator =
3010 rs.resolveUnaryOperator(tree.pos(), tree.getTag(), env, argtype);
3012 Type owntype = types.createErrorType(tree.type);
3013 if (operator.kind == MTH &&
3014 !argtype.isErroneous()) {
3015 owntype = (tree.getTag().isIncOrDecUnaryOp())
3016 ? tree.arg.type
3017 : operator.type.getReturnType();
3018 int opc = ((OperatorSymbol)operator).opcode;
3020 // If the argument is constant, fold it.
3021 if (argtype.constValue() != null) {
3022 Type ctype = cfolder.fold1(opc, argtype);
3023 if (ctype != null) {
3024 owntype = cfolder.coerce(ctype, owntype);
3026 // Remove constant types from arguments to
3027 // conserve space. The parser will fold concatenations
3028 // of string literals; the code here also
3029 // gets rid of intermediate results when some of the
3030 // operands are constant identifiers.
3031 if (tree.arg.type.tsym == syms.stringType.tsym) {
3032 tree.arg.type = syms.stringType;
3033 }
3034 }
3035 }
3036 }
3037 result = check(tree, owntype, VAL, resultInfo);
3038 }
3040 public void visitBinary(JCBinary tree) {
3041 // Attribute arguments.
3042 Type left = chk.checkNonVoid(tree.lhs.pos(), attribExpr(tree.lhs, env));
3043 Type right = chk.checkNonVoid(tree.lhs.pos(), attribExpr(tree.rhs, env));
3045 // Find operator.
3046 Symbol operator = tree.operator =
3047 rs.resolveBinaryOperator(tree.pos(), tree.getTag(), env, left, right);
3049 Type owntype = types.createErrorType(tree.type);
3050 if (operator.kind == MTH &&
3051 !left.isErroneous() &&
3052 !right.isErroneous()) {
3053 owntype = operator.type.getReturnType();
3054 // This will figure out when unboxing can happen and
3055 // choose the right comparison operator.
3056 int opc = chk.checkOperator(tree.lhs.pos(),
3057 (OperatorSymbol)operator,
3058 tree.getTag(),
3059 left,
3060 right);
3062 // If both arguments are constants, fold them.
3063 if (left.constValue() != null && right.constValue() != null) {
3064 Type ctype = cfolder.fold2(opc, left, right);
3065 if (ctype != null) {
3066 owntype = cfolder.coerce(ctype, owntype);
3068 // Remove constant types from arguments to
3069 // conserve space. The parser will fold concatenations
3070 // of string literals; the code here also
3071 // gets rid of intermediate results when some of the
3072 // operands are constant identifiers.
3073 if (tree.lhs.type.tsym == syms.stringType.tsym) {
3074 tree.lhs.type = syms.stringType;
3075 }
3076 if (tree.rhs.type.tsym == syms.stringType.tsym) {
3077 tree.rhs.type = syms.stringType;
3078 }
3079 }
3080 }
3082 // Check that argument types of a reference ==, != are
3083 // castable to each other, (JLS 15.21). Note: unboxing
3084 // comparisons will not have an acmp* opc at this point.
3085 if ((opc == ByteCodes.if_acmpeq || opc == ByteCodes.if_acmpne)) {
3086 if (!types.isEqualityComparable(left, right,
3087 new Warner(tree.pos()))) {
3088 log.error(tree.pos(), "incomparable.types", left, right);
3089 }
3090 }
3092 chk.checkDivZero(tree.rhs.pos(), operator, right);
3093 }
3094 result = check(tree, owntype, VAL, resultInfo);
3095 }
3097 public void visitTypeCast(final JCTypeCast tree) {
3098 Type clazztype = attribType(tree.clazz, env);
3099 chk.validate(tree.clazz, env, false);
3100 //a fresh environment is required for 292 inference to work properly ---
3101 //see Infer.instantiatePolymorphicSignatureInstance()
3102 Env<AttrContext> localEnv = env.dup(tree);
3103 //should we propagate the target type?
3104 final ResultInfo castInfo;
3105 JCExpression expr = TreeInfo.skipParens(tree.expr);
3106 boolean isPoly = allowPoly && (expr.hasTag(LAMBDA) || expr.hasTag(REFERENCE));
3107 if (isPoly) {
3108 //expression is a poly - we need to propagate target type info
3109 castInfo = new ResultInfo(VAL, clazztype, new Check.NestedCheckContext(resultInfo.checkContext) {
3110 @Override
3111 public boolean compatible(Type found, Type req, Warner warn) {
3112 return types.isCastable(found, req, warn);
3113 }
3114 });
3115 } else {
3116 //standalone cast - target-type info is not propagated
3117 castInfo = unknownExprInfo;
3118 }
3119 Type exprtype = attribTree(tree.expr, localEnv, castInfo);
3120 Type owntype = isPoly ? clazztype : chk.checkCastable(tree.expr.pos(), exprtype, clazztype);
3121 if (exprtype.constValue() != null)
3122 owntype = cfolder.coerce(exprtype, owntype);
3123 result = check(tree, capture(owntype), VAL, resultInfo);
3124 if (!isPoly)
3125 chk.checkRedundantCast(localEnv, tree);
3126 }
3128 public void visitTypeTest(JCInstanceOf tree) {
3129 Type exprtype = chk.checkNullOrRefType(
3130 tree.expr.pos(), attribExpr(tree.expr, env));
3131 Type clazztype = attribType(tree.clazz, env);
3132 if (!clazztype.hasTag(TYPEVAR)) {
3133 clazztype = chk.checkClassOrArrayType(tree.clazz.pos(), clazztype);
3134 }
3135 if (!clazztype.isErroneous() && !types.isReifiable(clazztype)) {
3136 log.error(tree.clazz.pos(), "illegal.generic.type.for.instof");
3137 clazztype = types.createErrorType(clazztype);
3138 }
3139 chk.validate(tree.clazz, env, false);
3140 chk.checkCastable(tree.expr.pos(), exprtype, clazztype);
3141 result = check(tree, syms.booleanType, VAL, resultInfo);
3142 }
3144 public void visitIndexed(JCArrayAccess tree) {
3145 Type owntype = types.createErrorType(tree.type);
3146 Type atype = attribExpr(tree.indexed, env);
3147 attribExpr(tree.index, env, syms.intType);
3148 if (types.isArray(atype))
3149 owntype = types.elemtype(atype);
3150 else if (!atype.hasTag(ERROR))
3151 log.error(tree.pos(), "array.req.but.found", atype);
3152 if ((pkind() & VAR) == 0) owntype = capture(owntype);
3153 result = check(tree, owntype, VAR, resultInfo);
3154 }
3156 public void visitIdent(JCIdent tree) {
3157 Symbol sym;
3159 // Find symbol
3160 if (pt().hasTag(METHOD) || pt().hasTag(FORALL)) {
3161 // If we are looking for a method, the prototype `pt' will be a
3162 // method type with the type of the call's arguments as parameters.
3163 env.info.pendingResolutionPhase = null;
3164 sym = rs.resolveMethod(tree.pos(), env, tree.name, pt().getParameterTypes(), pt().getTypeArguments());
3165 } else if (tree.sym != null && tree.sym.kind != VAR) {
3166 sym = tree.sym;
3167 } else {
3168 sym = rs.resolveIdent(tree.pos(), env, tree.name, pkind());
3169 }
3170 tree.sym = sym;
3172 // (1) Also find the environment current for the class where
3173 // sym is defined (`symEnv').
3174 // Only for pre-tiger versions (1.4 and earlier):
3175 // (2) Also determine whether we access symbol out of an anonymous
3176 // class in a this or super call. This is illegal for instance
3177 // members since such classes don't carry a this$n link.
3178 // (`noOuterThisPath').
3179 Env<AttrContext> symEnv = env;
3180 boolean noOuterThisPath = false;
3181 if (env.enclClass.sym.owner.kind != PCK && // we are in an inner class
3182 (sym.kind & (VAR | MTH | TYP)) != 0 &&
3183 sym.owner.kind == TYP &&
3184 tree.name != names._this && tree.name != names._super) {
3186 // Find environment in which identifier is defined.
3187 while (symEnv.outer != null &&
3188 !sym.isMemberOf(symEnv.enclClass.sym, types)) {
3189 if ((symEnv.enclClass.sym.flags() & NOOUTERTHIS) != 0)
3190 noOuterThisPath = !allowAnonOuterThis;
3191 symEnv = symEnv.outer;
3192 }
3193 }
3195 // If symbol is a variable, ...
3196 if (sym.kind == VAR) {
3197 VarSymbol v = (VarSymbol)sym;
3199 // ..., evaluate its initializer, if it has one, and check for
3200 // illegal forward reference.
3201 checkInit(tree, env, v, false);
3203 // If we are expecting a variable (as opposed to a value), check
3204 // that the variable is assignable in the current environment.
3205 if (pkind() == VAR)
3206 checkAssignable(tree.pos(), v, null, env);
3207 }
3209 // In a constructor body,
3210 // if symbol is a field or instance method, check that it is
3211 // not accessed before the supertype constructor is called.
3212 if ((symEnv.info.isSelfCall || noOuterThisPath) &&
3213 (sym.kind & (VAR | MTH)) != 0 &&
3214 sym.owner.kind == TYP &&
3215 (sym.flags() & STATIC) == 0) {
3216 chk.earlyRefError(tree.pos(), sym.kind == VAR ? sym : thisSym(tree.pos(), env));
3217 }
3218 Env<AttrContext> env1 = env;
3219 if (sym.kind != ERR && sym.kind != TYP && sym.owner != null && sym.owner != env1.enclClass.sym) {
3220 // If the found symbol is inaccessible, then it is
3221 // accessed through an enclosing instance. Locate this
3222 // enclosing instance:
3223 while (env1.outer != null && !rs.isAccessible(env, env1.enclClass.sym.type, sym))
3224 env1 = env1.outer;
3225 }
3226 result = checkId(tree, env1.enclClass.sym.type, sym, env, resultInfo);
3227 }
3229 public void visitSelect(JCFieldAccess tree) {
3230 // Determine the expected kind of the qualifier expression.
3231 int skind = 0;
3232 if (tree.name == names._this || tree.name == names._super ||
3233 tree.name == names._class)
3234 {
3235 skind = TYP;
3236 } else {
3237 if ((pkind() & PCK) != 0) skind = skind | PCK;
3238 if ((pkind() & TYP) != 0) skind = skind | TYP | PCK;
3239 if ((pkind() & (VAL | MTH)) != 0) skind = skind | VAL | TYP;
3240 }
3242 // Attribute the qualifier expression, and determine its symbol (if any).
3243 Type site = attribTree(tree.selected, env, new ResultInfo(skind, Infer.anyPoly));
3244 if ((pkind() & (PCK | TYP)) == 0)
3245 site = capture(site); // Capture field access
3247 // don't allow T.class T[].class, etc
3248 if (skind == TYP) {
3249 Type elt = site;
3250 while (elt.hasTag(ARRAY))
3251 elt = ((ArrayType)elt.unannotatedType()).elemtype;
3252 if (elt.hasTag(TYPEVAR)) {
3253 log.error(tree.pos(), "type.var.cant.be.deref");
3254 result = types.createErrorType(tree.type);
3255 return;
3256 }
3257 }
3259 // If qualifier symbol is a type or `super', assert `selectSuper'
3260 // for the selection. This is relevant for determining whether
3261 // protected symbols are accessible.
3262 Symbol sitesym = TreeInfo.symbol(tree.selected);
3263 boolean selectSuperPrev = env.info.selectSuper;
3264 env.info.selectSuper =
3265 sitesym != null &&
3266 sitesym.name == names._super;
3268 // Determine the symbol represented by the selection.
3269 env.info.pendingResolutionPhase = null;
3270 Symbol sym = selectSym(tree, sitesym, site, env, resultInfo);
3271 if (sym.exists() && !isType(sym) && (pkind() & (PCK | TYP)) != 0) {
3272 site = capture(site);
3273 sym = selectSym(tree, sitesym, site, env, resultInfo);
3274 }
3275 boolean varArgs = env.info.lastResolveVarargs();
3276 tree.sym = sym;
3278 if (site.hasTag(TYPEVAR) && !isType(sym) && sym.kind != ERR) {
3279 while (site.hasTag(TYPEVAR)) site = site.getUpperBound();
3280 site = capture(site);
3281 }
3283 // If that symbol is a variable, ...
3284 if (sym.kind == VAR) {
3285 VarSymbol v = (VarSymbol)sym;
3287 // ..., evaluate its initializer, if it has one, and check for
3288 // illegal forward reference.
3289 checkInit(tree, env, v, true);
3291 // If we are expecting a variable (as opposed to a value), check
3292 // that the variable is assignable in the current environment.
3293 if (pkind() == VAR)
3294 checkAssignable(tree.pos(), v, tree.selected, env);
3295 }
3297 if (sitesym != null &&
3298 sitesym.kind == VAR &&
3299 ((VarSymbol)sitesym).isResourceVariable() &&
3300 sym.kind == MTH &&
3301 sym.name.equals(names.close) &&
3302 sym.overrides(syms.autoCloseableClose, sitesym.type.tsym, types, true) &&
3303 env.info.lint.isEnabled(LintCategory.TRY)) {
3304 log.warning(LintCategory.TRY, tree, "try.explicit.close.call");
3305 }
3307 // Disallow selecting a type from an expression
3308 if (isType(sym) && (sitesym==null || (sitesym.kind&(TYP|PCK)) == 0)) {
3309 tree.type = check(tree.selected, pt(),
3310 sitesym == null ? VAL : sitesym.kind, new ResultInfo(TYP|PCK, pt()));
3311 }
3313 if (isType(sitesym)) {
3314 if (sym.name == names._this) {
3315 // If `C' is the currently compiled class, check that
3316 // C.this' does not appear in a call to a super(...)
3317 if (env.info.isSelfCall &&
3318 site.tsym == env.enclClass.sym) {
3319 chk.earlyRefError(tree.pos(), sym);
3320 }
3321 } else {
3322 // Check if type-qualified fields or methods are static (JLS)
3323 if ((sym.flags() & STATIC) == 0 &&
3324 !env.next.tree.hasTag(REFERENCE) &&
3325 sym.name != names._super &&
3326 (sym.kind == VAR || sym.kind == MTH)) {
3327 rs.accessBase(rs.new StaticError(sym),
3328 tree.pos(), site, sym.name, true);
3329 }
3330 }
3331 } else if (sym.kind != ERR && (sym.flags() & STATIC) != 0 && sym.name != names._class) {
3332 // If the qualified item is not a type and the selected item is static, report
3333 // a warning. Make allowance for the class of an array type e.g. Object[].class)
3334 chk.warnStatic(tree, "static.not.qualified.by.type", Kinds.kindName(sym.kind), sym.owner);
3335 }
3337 // If we are selecting an instance member via a `super', ...
3338 if (env.info.selectSuper && (sym.flags() & STATIC) == 0) {
3340 // Check that super-qualified symbols are not abstract (JLS)
3341 rs.checkNonAbstract(tree.pos(), sym);
3343 if (site.isRaw()) {
3344 // Determine argument types for site.
3345 Type site1 = types.asSuper(env.enclClass.sym.type, site.tsym);
3346 if (site1 != null) site = site1;
3347 }
3348 }
3350 env.info.selectSuper = selectSuperPrev;
3351 result = checkId(tree, site, sym, env, resultInfo);
3352 }
3353 //where
3354 /** Determine symbol referenced by a Select expression,
3355 *
3356 * @param tree The select tree.
3357 * @param site The type of the selected expression,
3358 * @param env The current environment.
3359 * @param resultInfo The current result.
3360 */
3361 private Symbol selectSym(JCFieldAccess tree,
3362 Symbol location,
3363 Type site,
3364 Env<AttrContext> env,
3365 ResultInfo resultInfo) {
3366 DiagnosticPosition pos = tree.pos();
3367 Name name = tree.name;
3368 switch (site.getTag()) {
3369 case PACKAGE:
3370 return rs.accessBase(
3371 rs.findIdentInPackage(env, site.tsym, name, resultInfo.pkind),
3372 pos, location, site, name, true);
3373 case ARRAY:
3374 case CLASS:
3375 if (resultInfo.pt.hasTag(METHOD) || resultInfo.pt.hasTag(FORALL)) {
3376 return rs.resolveQualifiedMethod(
3377 pos, env, location, site, name, resultInfo.pt.getParameterTypes(), resultInfo.pt.getTypeArguments());
3378 } else if (name == names._this || name == names._super) {
3379 return rs.resolveSelf(pos, env, site.tsym, name);
3380 } else if (name == names._class) {
3381 // In this case, we have already made sure in
3382 // visitSelect that qualifier expression is a type.
3383 Type t = syms.classType;
3384 List<Type> typeargs = allowGenerics
3385 ? List.of(types.erasure(site))
3386 : List.<Type>nil();
3387 t = new ClassType(t.getEnclosingType(), typeargs, t.tsym);
3388 return new VarSymbol(
3389 STATIC | PUBLIC | FINAL, names._class, t, site.tsym);
3390 } else {
3391 // We are seeing a plain identifier as selector.
3392 Symbol sym = rs.findIdentInType(env, site, name, resultInfo.pkind);
3393 if ((resultInfo.pkind & ERRONEOUS) == 0)
3394 sym = rs.accessBase(sym, pos, location, site, name, true);
3395 return sym;
3396 }
3397 case WILDCARD:
3398 throw new AssertionError(tree);
3399 case TYPEVAR:
3400 // Normally, site.getUpperBound() shouldn't be null.
3401 // It should only happen during memberEnter/attribBase
3402 // when determining the super type which *must* beac
3403 // done before attributing the type variables. In
3404 // other words, we are seeing this illegal program:
3405 // class B<T> extends A<T.foo> {}
3406 Symbol sym = (site.getUpperBound() != null)
3407 ? selectSym(tree, location, capture(site.getUpperBound()), env, resultInfo)
3408 : null;
3409 if (sym == null) {
3410 log.error(pos, "type.var.cant.be.deref");
3411 return syms.errSymbol;
3412 } else {
3413 Symbol sym2 = (sym.flags() & Flags.PRIVATE) != 0 ?
3414 rs.new AccessError(env, site, sym) :
3415 sym;
3416 rs.accessBase(sym2, pos, location, site, name, true);
3417 return sym;
3418 }
3419 case ERROR:
3420 // preserve identifier names through errors
3421 return types.createErrorType(name, site.tsym, site).tsym;
3422 default:
3423 // The qualifier expression is of a primitive type -- only
3424 // .class is allowed for these.
3425 if (name == names._class) {
3426 // In this case, we have already made sure in Select that
3427 // qualifier expression is a type.
3428 Type t = syms.classType;
3429 Type arg = types.boxedClass(site).type;
3430 t = new ClassType(t.getEnclosingType(), List.of(arg), t.tsym);
3431 return new VarSymbol(
3432 STATIC | PUBLIC | FINAL, names._class, t, site.tsym);
3433 } else {
3434 log.error(pos, "cant.deref", site);
3435 return syms.errSymbol;
3436 }
3437 }
3438 }
3440 /** Determine type of identifier or select expression and check that
3441 * (1) the referenced symbol is not deprecated
3442 * (2) the symbol's type is safe (@see checkSafe)
3443 * (3) if symbol is a variable, check that its type and kind are
3444 * compatible with the prototype and protokind.
3445 * (4) if symbol is an instance field of a raw type,
3446 * which is being assigned to, issue an unchecked warning if its
3447 * type changes under erasure.
3448 * (5) if symbol is an instance method of a raw type, issue an
3449 * unchecked warning if its argument types change under erasure.
3450 * If checks succeed:
3451 * If symbol is a constant, return its constant type
3452 * else if symbol is a method, return its result type
3453 * otherwise return its type.
3454 * Otherwise return errType.
3455 *
3456 * @param tree The syntax tree representing the identifier
3457 * @param site If this is a select, the type of the selected
3458 * expression, otherwise the type of the current class.
3459 * @param sym The symbol representing the identifier.
3460 * @param env The current environment.
3461 * @param resultInfo The expected result
3462 */
3463 Type checkId(JCTree tree,
3464 Type site,
3465 Symbol sym,
3466 Env<AttrContext> env,
3467 ResultInfo resultInfo) {
3468 return (resultInfo.pt.hasTag(FORALL) || resultInfo.pt.hasTag(METHOD)) ?
3469 checkMethodId(tree, site, sym, env, resultInfo) :
3470 checkIdInternal(tree, site, sym, resultInfo.pt, env, resultInfo);
3471 }
3473 Type checkMethodId(JCTree tree,
3474 Type site,
3475 Symbol sym,
3476 Env<AttrContext> env,
3477 ResultInfo resultInfo) {
3478 boolean isPolymorhicSignature =
3479 (sym.baseSymbol().flags() & SIGNATURE_POLYMORPHIC) != 0;
3480 return isPolymorhicSignature ?
3481 checkSigPolyMethodId(tree, site, sym, env, resultInfo) :
3482 checkMethodIdInternal(tree, site, sym, env, resultInfo);
3483 }
3485 Type checkSigPolyMethodId(JCTree tree,
3486 Type site,
3487 Symbol sym,
3488 Env<AttrContext> env,
3489 ResultInfo resultInfo) {
3490 //recover original symbol for signature polymorphic methods
3491 checkMethodIdInternal(tree, site, sym.baseSymbol(), env, resultInfo);
3492 env.info.pendingResolutionPhase = Resolve.MethodResolutionPhase.BASIC;
3493 return sym.type;
3494 }
3496 Type checkMethodIdInternal(JCTree tree,
3497 Type site,
3498 Symbol sym,
3499 Env<AttrContext> env,
3500 ResultInfo resultInfo) {
3501 if ((resultInfo.pkind & POLY) != 0) {
3502 Type pt = resultInfo.pt.map(deferredAttr.new RecoveryDeferredTypeMap(AttrMode.SPECULATIVE, sym, env.info.pendingResolutionPhase));
3503 Type owntype = checkIdInternal(tree, site, sym, pt, env, resultInfo);
3504 resultInfo.pt.map(deferredAttr.new RecoveryDeferredTypeMap(AttrMode.CHECK, sym, env.info.pendingResolutionPhase));
3505 return owntype;
3506 } else {
3507 return checkIdInternal(tree, site, sym, resultInfo.pt, env, resultInfo);
3508 }
3509 }
3511 Type checkIdInternal(JCTree tree,
3512 Type site,
3513 Symbol sym,
3514 Type pt,
3515 Env<AttrContext> env,
3516 ResultInfo resultInfo) {
3517 if (pt.isErroneous()) {
3518 return types.createErrorType(site);
3519 }
3520 Type owntype; // The computed type of this identifier occurrence.
3521 switch (sym.kind) {
3522 case TYP:
3523 // For types, the computed type equals the symbol's type,
3524 // except for two situations:
3525 owntype = sym.type;
3526 if (owntype.hasTag(CLASS)) {
3527 chk.checkForBadAuxiliaryClassAccess(tree.pos(), env, (ClassSymbol)sym);
3528 Type ownOuter = owntype.getEnclosingType();
3530 // (a) If the symbol's type is parameterized, erase it
3531 // because no type parameters were given.
3532 // We recover generic outer type later in visitTypeApply.
3533 if (owntype.tsym.type.getTypeArguments().nonEmpty()) {
3534 owntype = types.erasure(owntype);
3535 }
3537 // (b) If the symbol's type is an inner class, then
3538 // we have to interpret its outer type as a superclass
3539 // of the site type. Example:
3540 //
3541 // class Tree<A> { class Visitor { ... } }
3542 // class PointTree extends Tree<Point> { ... }
3543 // ...PointTree.Visitor...
3544 //
3545 // Then the type of the last expression above is
3546 // Tree<Point>.Visitor.
3547 else if (ownOuter.hasTag(CLASS) && site != ownOuter) {
3548 Type normOuter = site;
3549 if (normOuter.hasTag(CLASS)) {
3550 normOuter = types.asEnclosingSuper(site, ownOuter.tsym);
3551 }
3552 if (normOuter == null) // perhaps from an import
3553 normOuter = types.erasure(ownOuter);
3554 if (normOuter != ownOuter)
3555 owntype = new ClassType(
3556 normOuter, List.<Type>nil(), owntype.tsym);
3557 }
3558 }
3559 break;
3560 case VAR:
3561 VarSymbol v = (VarSymbol)sym;
3562 // Test (4): if symbol is an instance field of a raw type,
3563 // which is being assigned to, issue an unchecked warning if
3564 // its type changes under erasure.
3565 if (allowGenerics &&
3566 resultInfo.pkind == VAR &&
3567 v.owner.kind == TYP &&
3568 (v.flags() & STATIC) == 0 &&
3569 (site.hasTag(CLASS) || site.hasTag(TYPEVAR))) {
3570 Type s = types.asOuterSuper(site, v.owner);
3571 if (s != null &&
3572 s.isRaw() &&
3573 !types.isSameType(v.type, v.erasure(types))) {
3574 chk.warnUnchecked(tree.pos(),
3575 "unchecked.assign.to.var",
3576 v, s);
3577 }
3578 }
3579 // The computed type of a variable is the type of the
3580 // variable symbol, taken as a member of the site type.
3581 owntype = (sym.owner.kind == TYP &&
3582 sym.name != names._this && sym.name != names._super)
3583 ? types.memberType(site, sym)
3584 : sym.type;
3586 // If the variable is a constant, record constant value in
3587 // computed type.
3588 if (v.getConstValue() != null && isStaticReference(tree))
3589 owntype = owntype.constType(v.getConstValue());
3591 if (resultInfo.pkind == VAL) {
3592 owntype = capture(owntype); // capture "names as expressions"
3593 }
3594 break;
3595 case MTH: {
3596 owntype = checkMethod(site, sym,
3597 new ResultInfo(resultInfo.pkind, resultInfo.pt.getReturnType(), resultInfo.checkContext),
3598 env, TreeInfo.args(env.tree), resultInfo.pt.getParameterTypes(),
3599 resultInfo.pt.getTypeArguments());
3600 break;
3601 }
3602 case PCK: case ERR:
3603 owntype = sym.type;
3604 break;
3605 default:
3606 throw new AssertionError("unexpected kind: " + sym.kind +
3607 " in tree " + tree);
3608 }
3610 // Test (1): emit a `deprecation' warning if symbol is deprecated.
3611 // (for constructors, the error was given when the constructor was
3612 // resolved)
3614 if (sym.name != names.init) {
3615 chk.checkDeprecated(tree.pos(), env.info.scope.owner, sym);
3616 chk.checkSunAPI(tree.pos(), sym);
3617 chk.checkProfile(tree.pos(), sym);
3618 }
3620 // Test (3): if symbol is a variable, check that its type and
3621 // kind are compatible with the prototype and protokind.
3622 return check(tree, owntype, sym.kind, resultInfo);
3623 }
3625 /** Check that variable is initialized and evaluate the variable's
3626 * initializer, if not yet done. Also check that variable is not
3627 * referenced before it is defined.
3628 * @param tree The tree making up the variable reference.
3629 * @param env The current environment.
3630 * @param v The variable's symbol.
3631 */
3632 private void checkInit(JCTree tree,
3633 Env<AttrContext> env,
3634 VarSymbol v,
3635 boolean onlyWarning) {
3636 // System.err.println(v + " " + ((v.flags() & STATIC) != 0) + " " +
3637 // tree.pos + " " + v.pos + " " +
3638 // Resolve.isStatic(env));//DEBUG
3640 // A forward reference is diagnosed if the declaration position
3641 // of the variable is greater than the current tree position
3642 // and the tree and variable definition occur in the same class
3643 // definition. Note that writes don't count as references.
3644 // This check applies only to class and instance
3645 // variables. Local variables follow different scope rules,
3646 // and are subject to definite assignment checking.
3647 if ((env.info.enclVar == v || v.pos > tree.pos) &&
3648 v.owner.kind == TYP &&
3649 canOwnInitializer(owner(env)) &&
3650 v.owner == env.info.scope.owner.enclClass() &&
3651 ((v.flags() & STATIC) != 0) == Resolve.isStatic(env) &&
3652 (!env.tree.hasTag(ASSIGN) ||
3653 TreeInfo.skipParens(((JCAssign) env.tree).lhs) != tree)) {
3654 String suffix = (env.info.enclVar == v) ?
3655 "self.ref" : "forward.ref";
3656 if (!onlyWarning || isStaticEnumField(v)) {
3657 log.error(tree.pos(), "illegal." + suffix);
3658 } else if (useBeforeDeclarationWarning) {
3659 log.warning(tree.pos(), suffix, v);
3660 }
3661 }
3663 v.getConstValue(); // ensure initializer is evaluated
3665 checkEnumInitializer(tree, env, v);
3666 }
3668 /**
3669 * Check for illegal references to static members of enum. In
3670 * an enum type, constructors and initializers may not
3671 * reference its static members unless they are constant.
3672 *
3673 * @param tree The tree making up the variable reference.
3674 * @param env The current environment.
3675 * @param v The variable's symbol.
3676 * @jls section 8.9 Enums
3677 */
3678 private void checkEnumInitializer(JCTree tree, Env<AttrContext> env, VarSymbol v) {
3679 // JLS:
3680 //
3681 // "It is a compile-time error to reference a static field
3682 // of an enum type that is not a compile-time constant
3683 // (15.28) from constructors, instance initializer blocks,
3684 // or instance variable initializer expressions of that
3685 // type. It is a compile-time error for the constructors,
3686 // instance initializer blocks, or instance variable
3687 // initializer expressions of an enum constant e to refer
3688 // to itself or to an enum constant of the same type that
3689 // is declared to the right of e."
3690 if (isStaticEnumField(v)) {
3691 ClassSymbol enclClass = env.info.scope.owner.enclClass();
3693 if (enclClass == null || enclClass.owner == null)
3694 return;
3696 // See if the enclosing class is the enum (or a
3697 // subclass thereof) declaring v. If not, this
3698 // reference is OK.
3699 if (v.owner != enclClass && !types.isSubtype(enclClass.type, v.owner.type))
3700 return;
3702 // If the reference isn't from an initializer, then
3703 // the reference is OK.
3704 if (!Resolve.isInitializer(env))
3705 return;
3707 log.error(tree.pos(), "illegal.enum.static.ref");
3708 }
3709 }
3711 /** Is the given symbol a static, non-constant field of an Enum?
3712 * Note: enum literals should not be regarded as such
3713 */
3714 private boolean isStaticEnumField(VarSymbol v) {
3715 return Flags.isEnum(v.owner) &&
3716 Flags.isStatic(v) &&
3717 !Flags.isConstant(v) &&
3718 v.name != names._class;
3719 }
3721 /** Can the given symbol be the owner of code which forms part
3722 * if class initialization? This is the case if the symbol is
3723 * a type or field, or if the symbol is the synthetic method.
3724 * owning a block.
3725 */
3726 private boolean canOwnInitializer(Symbol sym) {
3727 return
3728 (sym.kind & (VAR | TYP)) != 0 ||
3729 (sym.kind == MTH && (sym.flags() & BLOCK) != 0);
3730 }
3732 Warner noteWarner = new Warner();
3734 /**
3735 * Check that method arguments conform to its instantiation.
3736 **/
3737 public Type checkMethod(Type site,
3738 final Symbol sym,
3739 ResultInfo resultInfo,
3740 Env<AttrContext> env,
3741 final List<JCExpression> argtrees,
3742 List<Type> argtypes,
3743 List<Type> typeargtypes) {
3744 // Test (5): if symbol is an instance method of a raw type, issue
3745 // an unchecked warning if its argument types change under erasure.
3746 if (allowGenerics &&
3747 (sym.flags() & STATIC) == 0 &&
3748 (site.hasTag(CLASS) || site.hasTag(TYPEVAR))) {
3749 Type s = types.asOuterSuper(site, sym.owner);
3750 if (s != null && s.isRaw() &&
3751 !types.isSameTypes(sym.type.getParameterTypes(),
3752 sym.erasure(types).getParameterTypes())) {
3753 chk.warnUnchecked(env.tree.pos(),
3754 "unchecked.call.mbr.of.raw.type",
3755 sym, s);
3756 }
3757 }
3759 if (env.info.defaultSuperCallSite != null) {
3760 for (Type sup : types.interfaces(env.enclClass.type).prepend(types.supertype((env.enclClass.type)))) {
3761 if (!sup.tsym.isSubClass(sym.enclClass(), types) ||
3762 types.isSameType(sup, env.info.defaultSuperCallSite)) continue;
3763 List<MethodSymbol> icand_sup =
3764 types.interfaceCandidates(sup, (MethodSymbol)sym);
3765 if (icand_sup.nonEmpty() &&
3766 icand_sup.head != sym &&
3767 icand_sup.head.overrides(sym, icand_sup.head.enclClass(), types, true)) {
3768 log.error(env.tree.pos(), "illegal.default.super.call", env.info.defaultSuperCallSite,
3769 diags.fragment("overridden.default", sym, sup));
3770 break;
3771 }
3772 }
3773 env.info.defaultSuperCallSite = null;
3774 }
3776 if (sym.isStatic() && site.isInterface() && env.tree.hasTag(APPLY)) {
3777 JCMethodInvocation app = (JCMethodInvocation)env.tree;
3778 if (app.meth.hasTag(SELECT) &&
3779 !TreeInfo.isStaticSelector(((JCFieldAccess)app.meth).selected, names)) {
3780 log.error(env.tree.pos(), "illegal.static.intf.meth.call", site);
3781 }
3782 }
3784 // Compute the identifier's instantiated type.
3785 // For methods, we need to compute the instance type by
3786 // Resolve.instantiate from the symbol's type as well as
3787 // any type arguments and value arguments.
3788 noteWarner.clear();
3789 try {
3790 Type owntype = rs.checkMethod(
3791 env,
3792 site,
3793 sym,
3794 resultInfo,
3795 argtypes,
3796 typeargtypes,
3797 noteWarner);
3799 DeferredAttr.DeferredTypeMap checkDeferredMap =
3800 deferredAttr.new DeferredTypeMap(DeferredAttr.AttrMode.CHECK, sym, env.info.pendingResolutionPhase);
3802 argtypes = Type.map(argtypes, checkDeferredMap);
3804 if (noteWarner.hasNonSilentLint(LintCategory.UNCHECKED)) {
3805 chk.warnUnchecked(env.tree.pos(),
3806 "unchecked.meth.invocation.applied",
3807 kindName(sym),
3808 sym.name,
3809 rs.methodArguments(sym.type.getParameterTypes()),
3810 rs.methodArguments(Type.map(argtypes, checkDeferredMap)),
3811 kindName(sym.location()),
3812 sym.location());
3813 owntype = new MethodType(owntype.getParameterTypes(),
3814 types.erasure(owntype.getReturnType()),
3815 types.erasure(owntype.getThrownTypes()),
3816 syms.methodClass);
3817 }
3819 return chk.checkMethod(owntype, sym, env, argtrees, argtypes, env.info.lastResolveVarargs(),
3820 resultInfo.checkContext.inferenceContext());
3821 } catch (Infer.InferenceException ex) {
3822 //invalid target type - propagate exception outwards or report error
3823 //depending on the current check context
3824 resultInfo.checkContext.report(env.tree.pos(), ex.getDiagnostic());
3825 return types.createErrorType(site);
3826 } catch (Resolve.InapplicableMethodException ex) {
3827 final JCDiagnostic diag = ex.getDiagnostic();
3828 Resolve.InapplicableSymbolError errSym = rs.new InapplicableSymbolError(null) {
3829 @Override
3830 protected Pair<Symbol, JCDiagnostic> errCandidate() {
3831 return new Pair<Symbol, JCDiagnostic>(sym, diag);
3832 }
3833 };
3834 List<Type> argtypes2 = Type.map(argtypes,
3835 rs.new ResolveDeferredRecoveryMap(AttrMode.CHECK, sym, env.info.pendingResolutionPhase));
3836 JCDiagnostic errDiag = errSym.getDiagnostic(JCDiagnostic.DiagnosticType.ERROR,
3837 env.tree, sym, site, sym.name, argtypes2, typeargtypes);
3838 log.report(errDiag);
3839 return types.createErrorType(site);
3840 }
3841 }
3843 public void visitLiteral(JCLiteral tree) {
3844 result = check(
3845 tree, litType(tree.typetag).constType(tree.value), VAL, resultInfo);
3846 }
3847 //where
3848 /** Return the type of a literal with given type tag.
3849 */
3850 Type litType(TypeTag tag) {
3851 return (tag == CLASS) ? syms.stringType : syms.typeOfTag[tag.ordinal()];
3852 }
3854 public void visitTypeIdent(JCPrimitiveTypeTree tree) {
3855 result = check(tree, syms.typeOfTag[tree.typetag.ordinal()], TYP, resultInfo);
3856 }
3858 public void visitTypeArray(JCArrayTypeTree tree) {
3859 Type etype = attribType(tree.elemtype, env);
3860 Type type = new ArrayType(etype, syms.arrayClass);
3861 result = check(tree, type, TYP, resultInfo);
3862 }
3864 /** Visitor method for parameterized types.
3865 * Bound checking is left until later, since types are attributed
3866 * before supertype structure is completely known
3867 */
3868 public void visitTypeApply(JCTypeApply tree) {
3869 Type owntype = types.createErrorType(tree.type);
3871 // Attribute functor part of application and make sure it's a class.
3872 Type clazztype = chk.checkClassType(tree.clazz.pos(), attribType(tree.clazz, env));
3874 // Attribute type parameters
3875 List<Type> actuals = attribTypes(tree.arguments, env);
3877 if (clazztype.hasTag(CLASS)) {
3878 List<Type> formals = clazztype.tsym.type.getTypeArguments();
3879 if (actuals.isEmpty()) //diamond
3880 actuals = formals;
3882 if (actuals.length() == formals.length()) {
3883 List<Type> a = actuals;
3884 List<Type> f = formals;
3885 while (a.nonEmpty()) {
3886 a.head = a.head.withTypeVar(f.head);
3887 a = a.tail;
3888 f = f.tail;
3889 }
3890 // Compute the proper generic outer
3891 Type clazzOuter = clazztype.getEnclosingType();
3892 if (clazzOuter.hasTag(CLASS)) {
3893 Type site;
3894 JCExpression clazz = TreeInfo.typeIn(tree.clazz);
3895 if (clazz.hasTag(IDENT)) {
3896 site = env.enclClass.sym.type;
3897 } else if (clazz.hasTag(SELECT)) {
3898 site = ((JCFieldAccess) clazz).selected.type;
3899 } else throw new AssertionError(""+tree);
3900 if (clazzOuter.hasTag(CLASS) && site != clazzOuter) {
3901 if (site.hasTag(CLASS))
3902 site = types.asOuterSuper(site, clazzOuter.tsym);
3903 if (site == null)
3904 site = types.erasure(clazzOuter);
3905 clazzOuter = site;
3906 }
3907 }
3908 owntype = new ClassType(clazzOuter, actuals, clazztype.tsym);
3909 } else {
3910 if (formals.length() != 0) {
3911 log.error(tree.pos(), "wrong.number.type.args",
3912 Integer.toString(formals.length()));
3913 } else {
3914 log.error(tree.pos(), "type.doesnt.take.params", clazztype.tsym);
3915 }
3916 owntype = types.createErrorType(tree.type);
3917 }
3918 }
3919 result = check(tree, owntype, TYP, resultInfo);
3920 }
3922 public void visitTypeUnion(JCTypeUnion tree) {
3923 ListBuffer<Type> multicatchTypes = new ListBuffer<>();
3924 ListBuffer<Type> all_multicatchTypes = null; // lazy, only if needed
3925 for (JCExpression typeTree : tree.alternatives) {
3926 Type ctype = attribType(typeTree, env);
3927 ctype = chk.checkType(typeTree.pos(),
3928 chk.checkClassType(typeTree.pos(), ctype),
3929 syms.throwableType);
3930 if (!ctype.isErroneous()) {
3931 //check that alternatives of a union type are pairwise
3932 //unrelated w.r.t. subtyping
3933 if (chk.intersects(ctype, multicatchTypes.toList())) {
3934 for (Type t : multicatchTypes) {
3935 boolean sub = types.isSubtype(ctype, t);
3936 boolean sup = types.isSubtype(t, ctype);
3937 if (sub || sup) {
3938 //assume 'a' <: 'b'
3939 Type a = sub ? ctype : t;
3940 Type b = sub ? t : ctype;
3941 log.error(typeTree.pos(), "multicatch.types.must.be.disjoint", a, b);
3942 }
3943 }
3944 }
3945 multicatchTypes.append(ctype);
3946 if (all_multicatchTypes != null)
3947 all_multicatchTypes.append(ctype);
3948 } else {
3949 if (all_multicatchTypes == null) {
3950 all_multicatchTypes = new ListBuffer<>();
3951 all_multicatchTypes.appendList(multicatchTypes);
3952 }
3953 all_multicatchTypes.append(ctype);
3954 }
3955 }
3956 Type t = check(tree, types.lub(multicatchTypes.toList()), TYP, resultInfo);
3957 if (t.hasTag(CLASS)) {
3958 List<Type> alternatives =
3959 ((all_multicatchTypes == null) ? multicatchTypes : all_multicatchTypes).toList();
3960 t = new UnionClassType((ClassType) t, alternatives);
3961 }
3962 tree.type = result = t;
3963 }
3965 public void visitTypeIntersection(JCTypeIntersection tree) {
3966 attribTypes(tree.bounds, env);
3967 tree.type = result = checkIntersection(tree, tree.bounds);
3968 }
3970 public void visitTypeParameter(JCTypeParameter tree) {
3971 TypeVar typeVar = (TypeVar) tree.type;
3973 if (tree.annotations != null && tree.annotations.nonEmpty()) {
3974 annotateType(tree, tree.annotations);
3975 }
3977 if (!typeVar.bound.isErroneous()) {
3978 //fixup type-parameter bound computed in 'attribTypeVariables'
3979 typeVar.bound = checkIntersection(tree, tree.bounds);
3980 }
3981 }
3983 Type checkIntersection(JCTree tree, List<JCExpression> bounds) {
3984 Set<Type> boundSet = new HashSet<Type>();
3985 if (bounds.nonEmpty()) {
3986 // accept class or interface or typevar as first bound.
3987 bounds.head.type = checkBase(bounds.head.type, bounds.head, env, false, false, false, false);
3988 boundSet.add(types.erasure(bounds.head.type));
3989 if (bounds.head.type.isErroneous()) {
3990 return bounds.head.type;
3991 }
3992 else if (bounds.head.type.hasTag(TYPEVAR)) {
3993 // if first bound was a typevar, do not accept further bounds.
3994 if (bounds.tail.nonEmpty()) {
3995 log.error(bounds.tail.head.pos(),
3996 "type.var.may.not.be.followed.by.other.bounds");
3997 return bounds.head.type;
3998 }
3999 } else {
4000 // if first bound was a class or interface, accept only interfaces
4001 // as further bounds.
4002 for (JCExpression bound : bounds.tail) {
4003 bound.type = checkBase(bound.type, bound, env, false, false, true, false);
4004 if (bound.type.isErroneous()) {
4005 bounds = List.of(bound);
4006 }
4007 else if (bound.type.hasTag(CLASS)) {
4008 chk.checkNotRepeated(bound.pos(), types.erasure(bound.type), boundSet);
4009 }
4010 }
4011 }
4012 }
4014 if (bounds.length() == 0) {
4015 return syms.objectType;
4016 } else if (bounds.length() == 1) {
4017 return bounds.head.type;
4018 } else {
4019 Type owntype = types.makeCompoundType(TreeInfo.types(bounds));
4020 if (tree.hasTag(TYPEINTERSECTION)) {
4021 ((IntersectionClassType)owntype).intersectionKind =
4022 IntersectionClassType.IntersectionKind.EXPLICIT;
4023 }
4024 // ... the variable's bound is a class type flagged COMPOUND
4025 // (see comment for TypeVar.bound).
4026 // In this case, generate a class tree that represents the
4027 // bound class, ...
4028 JCExpression extending;
4029 List<JCExpression> implementing;
4030 if (!bounds.head.type.isInterface()) {
4031 extending = bounds.head;
4032 implementing = bounds.tail;
4033 } else {
4034 extending = null;
4035 implementing = bounds;
4036 }
4037 JCClassDecl cd = make.at(tree).ClassDef(
4038 make.Modifiers(PUBLIC | ABSTRACT),
4039 names.empty, List.<JCTypeParameter>nil(),
4040 extending, implementing, List.<JCTree>nil());
4042 ClassSymbol c = (ClassSymbol)owntype.tsym;
4043 Assert.check((c.flags() & COMPOUND) != 0);
4044 cd.sym = c;
4045 c.sourcefile = env.toplevel.sourcefile;
4047 // ... and attribute the bound class
4048 c.flags_field |= UNATTRIBUTED;
4049 Env<AttrContext> cenv = enter.classEnv(cd, env);
4050 enter.typeEnvs.put(c, cenv);
4051 attribClass(c);
4052 return owntype;
4053 }
4054 }
4056 public void visitWildcard(JCWildcard tree) {
4057 //- System.err.println("visitWildcard("+tree+");");//DEBUG
4058 Type type = (tree.kind.kind == BoundKind.UNBOUND)
4059 ? syms.objectType
4060 : attribType(tree.inner, env);
4061 result = check(tree, new WildcardType(chk.checkRefType(tree.pos(), type),
4062 tree.kind.kind,
4063 syms.boundClass),
4064 TYP, resultInfo);
4065 }
4067 public void visitAnnotation(JCAnnotation tree) {
4068 Assert.error("should be handled in Annotate");
4069 }
4071 public void visitAnnotatedType(JCAnnotatedType tree) {
4072 Type underlyingType = attribType(tree.getUnderlyingType(), env);
4073 this.attribAnnotationTypes(tree.annotations, env);
4074 annotateType(tree, tree.annotations);
4075 result = tree.type = underlyingType;
4076 }
4078 /**
4079 * Apply the annotations to the particular type.
4080 */
4081 public void annotateType(final JCTree tree, final List<JCAnnotation> annotations) {
4082 annotate.typeAnnotation(new Annotate.Worker() {
4083 @Override
4084 public String toString() {
4085 return "annotate " + annotations + " onto " + tree;
4086 }
4087 @Override
4088 public void run() {
4089 List<Attribute.TypeCompound> compounds = fromAnnotations(annotations);
4090 if (annotations.size() == compounds.size()) {
4091 // All annotations were successfully converted into compounds
4092 tree.type = tree.type.unannotatedType().annotatedType(compounds);
4093 }
4094 }
4095 });
4096 }
4098 private static List<Attribute.TypeCompound> fromAnnotations(List<JCAnnotation> annotations) {
4099 if (annotations.isEmpty())
4100 return List.nil();
4102 ListBuffer<Attribute.TypeCompound> buf = new ListBuffer<>();
4103 for (JCAnnotation anno : annotations) {
4104 if (anno.attribute != null) {
4105 // TODO: this null-check is only needed for an obscure
4106 // ordering issue, where annotate.flush is called when
4107 // the attribute is not set yet. For an example failure
4108 // try the referenceinfos/NestedTypes.java test.
4109 // Any better solutions?
4110 buf.append((Attribute.TypeCompound) anno.attribute);
4111 }
4112 }
4113 return buf.toList();
4114 }
4116 public void visitErroneous(JCErroneous tree) {
4117 if (tree.errs != null)
4118 for (JCTree err : tree.errs)
4119 attribTree(err, env, new ResultInfo(ERR, pt()));
4120 result = tree.type = syms.errType;
4121 }
4123 /** Default visitor method for all other trees.
4124 */
4125 public void visitTree(JCTree tree) {
4126 throw new AssertionError();
4127 }
4129 /**
4130 * Attribute an env for either a top level tree or class declaration.
4131 */
4132 public void attrib(Env<AttrContext> env) {
4133 if (env.tree.hasTag(TOPLEVEL))
4134 attribTopLevel(env);
4135 else
4136 attribClass(env.tree.pos(), env.enclClass.sym);
4137 }
4139 /**
4140 * Attribute a top level tree. These trees are encountered when the
4141 * package declaration has annotations.
4142 */
4143 public void attribTopLevel(Env<AttrContext> env) {
4144 JCCompilationUnit toplevel = env.toplevel;
4145 try {
4146 annotate.flush();
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 deferredLintHandler.flush(env.tree);
4215 env.info.returnResult = null;
4216 // java.lang.Enum may not be subclassed by a non-enum
4217 if (st.tsym == syms.enumSym &&
4218 ((c.flags_field & (Flags.ENUM|Flags.COMPOUND)) == 0))
4219 log.error(env.tree.pos(), "enum.no.subclassing");
4221 // Enums may not be extended by source-level classes
4222 if (st.tsym != null &&
4223 ((st.tsym.flags_field & Flags.ENUM) != 0) &&
4224 ((c.flags_field & (Flags.ENUM | Flags.COMPOUND)) == 0)) {
4225 log.error(env.tree.pos(), "enum.types.not.extensible");
4226 }
4227 attribClassBody(env, c);
4229 chk.checkDeprecatedAnnotation(env.tree.pos(), c);
4230 chk.checkClassOverrideEqualsAndHashIfNeeded(env.tree.pos(), c);
4231 chk.checkFunctionalInterface((JCClassDecl) env.tree, c);
4232 } finally {
4233 env.info.returnResult = prevReturnRes;
4234 log.useSource(prev);
4235 chk.setLint(prevLint);
4236 }
4238 }
4239 }
4241 public void visitImport(JCImport tree) {
4242 // nothing to do
4243 }
4245 /** Finish the attribution of a class. */
4246 private void attribClassBody(Env<AttrContext> env, ClassSymbol c) {
4247 JCClassDecl tree = (JCClassDecl)env.tree;
4248 Assert.check(c == tree.sym);
4250 // Validate type parameters, supertype and interfaces.
4251 attribStats(tree.typarams, env);
4252 if (!c.isAnonymous()) {
4253 //already checked if anonymous
4254 chk.validate(tree.typarams, env);
4255 chk.validate(tree.extending, env);
4256 chk.validate(tree.implementing, env);
4257 }
4259 // If this is a non-abstract class, check that it has no abstract
4260 // methods or unimplemented methods of an implemented interface.
4261 if ((c.flags() & (ABSTRACT | INTERFACE)) == 0) {
4262 if (!relax)
4263 chk.checkAllDefined(tree.pos(), c);
4264 }
4266 if ((c.flags() & ANNOTATION) != 0) {
4267 if (tree.implementing.nonEmpty())
4268 log.error(tree.implementing.head.pos(),
4269 "cant.extend.intf.annotation");
4270 if (tree.typarams.nonEmpty())
4271 log.error(tree.typarams.head.pos(),
4272 "intf.annotation.cant.have.type.params");
4274 // If this annotation has a @Repeatable, validate
4275 Attribute.Compound repeatable = c.attribute(syms.repeatableType.tsym);
4276 if (repeatable != null) {
4277 // get diagnostic position for error reporting
4278 DiagnosticPosition cbPos = getDiagnosticPosition(tree, repeatable.type);
4279 Assert.checkNonNull(cbPos);
4281 chk.validateRepeatable(c, repeatable, cbPos);
4282 }
4283 } else {
4284 // Check that all extended classes and interfaces
4285 // are compatible (i.e. no two define methods with same arguments
4286 // yet different return types). (JLS 8.4.6.3)
4287 chk.checkCompatibleSupertypes(tree.pos(), c.type);
4288 if (allowDefaultMethods) {
4289 chk.checkDefaultMethodClashes(tree.pos(), c.type);
4290 }
4291 }
4293 // Check that class does not import the same parameterized interface
4294 // with two different argument lists.
4295 chk.checkClassBounds(tree.pos(), c.type);
4297 tree.type = c.type;
4299 for (List<JCTypeParameter> l = tree.typarams;
4300 l.nonEmpty(); l = l.tail) {
4301 Assert.checkNonNull(env.info.scope.lookup(l.head.name).scope);
4302 }
4304 // Check that a generic class doesn't extend Throwable
4305 if (!c.type.allparams().isEmpty() && types.isSubtype(c.type, syms.throwableType))
4306 log.error(tree.extending.pos(), "generic.throwable");
4308 // Check that all methods which implement some
4309 // method conform to the method they implement.
4310 chk.checkImplementations(tree);
4312 //check that a resource implementing AutoCloseable cannot throw InterruptedException
4313 checkAutoCloseable(tree.pos(), env, c.type);
4315 for (List<JCTree> l = tree.defs; l.nonEmpty(); l = l.tail) {
4316 // Attribute declaration
4317 attribStat(l.head, env);
4318 // Check that declarations in inner classes are not static (JLS 8.1.2)
4319 // Make an exception for static constants.
4320 if (c.owner.kind != PCK &&
4321 ((c.flags() & STATIC) == 0 || c.name == names.empty) &&
4322 (TreeInfo.flags(l.head) & (STATIC | INTERFACE)) != 0) {
4323 Symbol sym = null;
4324 if (l.head.hasTag(VARDEF)) sym = ((JCVariableDecl) l.head).sym;
4325 if (sym == null ||
4326 sym.kind != VAR ||
4327 ((VarSymbol) sym).getConstValue() == null)
4328 log.error(l.head.pos(), "icls.cant.have.static.decl", c);
4329 }
4330 }
4332 // Check for cycles among non-initial constructors.
4333 chk.checkCyclicConstructors(tree);
4335 // Check for cycles among annotation elements.
4336 chk.checkNonCyclicElements(tree);
4338 // Check for proper use of serialVersionUID
4339 if (env.info.lint.isEnabled(LintCategory.SERIAL) &&
4340 isSerializable(c) &&
4341 (c.flags() & Flags.ENUM) == 0 &&
4342 checkForSerial(c)) {
4343 checkSerialVersionUID(tree, c);
4344 }
4345 if (allowTypeAnnos) {
4346 // Correctly organize the postions of the type annotations
4347 typeAnnotations.organizeTypeAnnotationsBodies(tree);
4349 // Check type annotations applicability rules
4350 validateTypeAnnotations(tree, false);
4351 }
4352 }
4353 // where
4354 boolean checkForSerial(ClassSymbol c) {
4355 if ((c.flags() & ABSTRACT) == 0) {
4356 return true;
4357 } else {
4358 return c.members().anyMatch(anyNonAbstractOrDefaultMethod);
4359 }
4360 }
4362 public static final Filter<Symbol> anyNonAbstractOrDefaultMethod = new Filter<Symbol>() {
4363 @Override
4364 public boolean accepts(Symbol s) {
4365 return s.kind == Kinds.MTH &&
4366 (s.flags() & (DEFAULT | ABSTRACT)) != ABSTRACT;
4367 }
4368 };
4370 /** get a diagnostic position for an attribute of Type t, or null if attribute missing */
4371 private DiagnosticPosition getDiagnosticPosition(JCClassDecl tree, Type t) {
4372 for(List<JCAnnotation> al = tree.mods.annotations; !al.isEmpty(); al = al.tail) {
4373 if (types.isSameType(al.head.annotationType.type, t))
4374 return al.head.pos();
4375 }
4377 return null;
4378 }
4380 /** check if a class is a subtype of Serializable, if that is available. */
4381 private boolean isSerializable(ClassSymbol c) {
4382 try {
4383 syms.serializableType.complete();
4384 }
4385 catch (CompletionFailure e) {
4386 return false;
4387 }
4388 return types.isSubtype(c.type, syms.serializableType);
4389 }
4391 /** Check that an appropriate serialVersionUID member is defined. */
4392 private void checkSerialVersionUID(JCClassDecl tree, ClassSymbol c) {
4394 // check for presence of serialVersionUID
4395 Scope.Entry e = c.members().lookup(names.serialVersionUID);
4396 while (e.scope != null && e.sym.kind != VAR) e = e.next();
4397 if (e.scope == null) {
4398 log.warning(LintCategory.SERIAL,
4399 tree.pos(), "missing.SVUID", c);
4400 return;
4401 }
4403 // check that it is static final
4404 VarSymbol svuid = (VarSymbol)e.sym;
4405 if ((svuid.flags() & (STATIC | FINAL)) !=
4406 (STATIC | FINAL))
4407 log.warning(LintCategory.SERIAL,
4408 TreeInfo.diagnosticPositionFor(svuid, tree), "improper.SVUID", c);
4410 // check that it is long
4411 else if (!svuid.type.hasTag(LONG))
4412 log.warning(LintCategory.SERIAL,
4413 TreeInfo.diagnosticPositionFor(svuid, tree), "long.SVUID", c);
4415 // check constant
4416 else if (svuid.getConstValue() == null)
4417 log.warning(LintCategory.SERIAL,
4418 TreeInfo.diagnosticPositionFor(svuid, tree), "constant.SVUID", c);
4419 }
4421 private Type capture(Type type) {
4422 return types.capture(type);
4423 }
4425 public void validateTypeAnnotations(JCTree tree, boolean sigOnly) {
4426 tree.accept(new TypeAnnotationsValidator(sigOnly));
4427 }
4428 //where
4429 private final class TypeAnnotationsValidator extends TreeScanner {
4431 private final boolean sigOnly;
4432 public TypeAnnotationsValidator(boolean sigOnly) {
4433 this.sigOnly = sigOnly;
4434 }
4436 public void visitAnnotation(JCAnnotation tree) {
4437 chk.validateTypeAnnotation(tree, false);
4438 super.visitAnnotation(tree);
4439 }
4440 public void visitAnnotatedType(JCAnnotatedType tree) {
4441 if (!tree.underlyingType.type.isErroneous()) {
4442 super.visitAnnotatedType(tree);
4443 }
4444 }
4445 public void visitTypeParameter(JCTypeParameter tree) {
4446 chk.validateTypeAnnotations(tree.annotations, true);
4447 scan(tree.bounds);
4448 // Don't call super.
4449 // This is needed because above we call validateTypeAnnotation with
4450 // false, which would forbid annotations on type parameters.
4451 // super.visitTypeParameter(tree);
4452 }
4453 public void visitMethodDef(JCMethodDecl tree) {
4454 if (tree.recvparam != null &&
4455 tree.recvparam.vartype.type.getKind() != TypeKind.ERROR) {
4456 checkForDeclarationAnnotations(tree.recvparam.mods.annotations,
4457 tree.recvparam.vartype.type.tsym);
4458 }
4459 if (tree.restype != null && tree.restype.type != null) {
4460 validateAnnotatedType(tree.restype, tree.restype.type);
4461 }
4462 if (sigOnly) {
4463 scan(tree.mods);
4464 scan(tree.restype);
4465 scan(tree.typarams);
4466 scan(tree.recvparam);
4467 scan(tree.params);
4468 scan(tree.thrown);
4469 } else {
4470 scan(tree.defaultValue);
4471 scan(tree.body);
4472 }
4473 }
4474 public void visitVarDef(final JCVariableDecl tree) {
4475 if (tree.sym != null && tree.sym.type != null)
4476 validateAnnotatedType(tree.vartype, tree.sym.type);
4477 scan(tree.mods);
4478 scan(tree.vartype);
4479 if (!sigOnly) {
4480 scan(tree.init);
4481 }
4482 }
4483 public void visitTypeCast(JCTypeCast tree) {
4484 if (tree.clazz != null && tree.clazz.type != null)
4485 validateAnnotatedType(tree.clazz, tree.clazz.type);
4486 super.visitTypeCast(tree);
4487 }
4488 public void visitTypeTest(JCInstanceOf tree) {
4489 if (tree.clazz != null && tree.clazz.type != null)
4490 validateAnnotatedType(tree.clazz, tree.clazz.type);
4491 super.visitTypeTest(tree);
4492 }
4493 public void visitNewClass(JCNewClass tree) {
4494 if (tree.clazz.type != null)
4495 validateAnnotatedType(tree.clazz, tree.clazz.type);
4496 super.visitNewClass(tree);
4497 }
4498 public void visitNewArray(JCNewArray tree) {
4499 if (tree.elemtype != null && tree.elemtype.type != null)
4500 validateAnnotatedType(tree.elemtype, tree.elemtype.type);
4501 super.visitNewArray(tree);
4502 }
4504 @Override
4505 public void visitClassDef(JCClassDecl tree) {
4506 if (sigOnly) {
4507 scan(tree.mods);
4508 scan(tree.typarams);
4509 scan(tree.extending);
4510 scan(tree.implementing);
4511 }
4512 for (JCTree member : tree.defs) {
4513 if (member.hasTag(Tag.CLASSDEF)) {
4514 continue;
4515 }
4516 scan(member);
4517 }
4518 }
4520 @Override
4521 public void visitBlock(JCBlock tree) {
4522 if (!sigOnly) {
4523 scan(tree.stats);
4524 }
4525 }
4527 /* I would want to model this after
4528 * com.sun.tools.javac.comp.Check.Validator.visitSelectInternal(JCFieldAccess)
4529 * and override visitSelect and visitTypeApply.
4530 * However, we only set the annotated type in the top-level type
4531 * of the symbol.
4532 * Therefore, we need to override each individual location where a type
4533 * can occur.
4534 */
4535 private void validateAnnotatedType(final JCTree errtree, final Type type) {
4536 // System.out.println("Attr.validateAnnotatedType: " + errtree + " type: " + type);
4538 if (type.isPrimitiveOrVoid()) {
4539 return;
4540 }
4542 JCTree enclTr = errtree;
4543 Type enclTy = type;
4545 boolean repeat = true;
4546 while (repeat) {
4547 if (enclTr.hasTag(TYPEAPPLY)) {
4548 List<Type> tyargs = enclTy.getTypeArguments();
4549 List<JCExpression> trargs = ((JCTypeApply)enclTr).getTypeArguments();
4550 if (trargs.length() > 0) {
4551 // Nothing to do for diamonds
4552 if (tyargs.length() == trargs.length()) {
4553 for (int i = 0; i < tyargs.length(); ++i) {
4554 validateAnnotatedType(trargs.get(i), tyargs.get(i));
4555 }
4556 }
4557 // If the lengths don't match, it's either a diamond
4558 // or some nested type that redundantly provides
4559 // type arguments in the tree.
4560 }
4562 // Look at the clazz part of a generic type
4563 enclTr = ((JCTree.JCTypeApply)enclTr).clazz;
4564 }
4566 if (enclTr.hasTag(SELECT)) {
4567 enclTr = ((JCTree.JCFieldAccess)enclTr).getExpression();
4568 if (enclTy != null &&
4569 !enclTy.hasTag(NONE)) {
4570 enclTy = enclTy.getEnclosingType();
4571 }
4572 } else if (enclTr.hasTag(ANNOTATED_TYPE)) {
4573 JCAnnotatedType at = (JCTree.JCAnnotatedType) enclTr;
4574 if (enclTy == null ||
4575 enclTy.hasTag(NONE)) {
4576 if (at.getAnnotations().size() == 1) {
4577 log.error(at.underlyingType.pos(), "cant.type.annotate.scoping.1", at.getAnnotations().head.attribute);
4578 } else {
4579 ListBuffer<Attribute.Compound> comps = new ListBuffer<Attribute.Compound>();
4580 for (JCAnnotation an : at.getAnnotations()) {
4581 comps.add(an.attribute);
4582 }
4583 log.error(at.underlyingType.pos(), "cant.type.annotate.scoping", comps.toList());
4584 }
4585 repeat = false;
4586 }
4587 enclTr = at.underlyingType;
4588 // enclTy doesn't need to be changed
4589 } else if (enclTr.hasTag(IDENT)) {
4590 repeat = false;
4591 } else if (enclTr.hasTag(JCTree.Tag.WILDCARD)) {
4592 JCWildcard wc = (JCWildcard) enclTr;
4593 if (wc.getKind() == JCTree.Kind.EXTENDS_WILDCARD) {
4594 validateAnnotatedType(wc.getBound(), ((WildcardType)enclTy.unannotatedType()).getExtendsBound());
4595 } else if (wc.getKind() == JCTree.Kind.SUPER_WILDCARD) {
4596 validateAnnotatedType(wc.getBound(), ((WildcardType)enclTy.unannotatedType()).getSuperBound());
4597 } else {
4598 // Nothing to do for UNBOUND
4599 }
4600 repeat = false;
4601 } else if (enclTr.hasTag(TYPEARRAY)) {
4602 JCArrayTypeTree art = (JCArrayTypeTree) enclTr;
4603 validateAnnotatedType(art.getType(), ((ArrayType)enclTy.unannotatedType()).getComponentType());
4604 repeat = false;
4605 } else if (enclTr.hasTag(TYPEUNION)) {
4606 JCTypeUnion ut = (JCTypeUnion) enclTr;
4607 for (JCTree t : ut.getTypeAlternatives()) {
4608 validateAnnotatedType(t, t.type);
4609 }
4610 repeat = false;
4611 } else if (enclTr.hasTag(TYPEINTERSECTION)) {
4612 JCTypeIntersection it = (JCTypeIntersection) enclTr;
4613 for (JCTree t : it.getBounds()) {
4614 validateAnnotatedType(t, t.type);
4615 }
4616 repeat = false;
4617 } else if (enclTr.getKind() == JCTree.Kind.PRIMITIVE_TYPE) {
4618 // This happens in test TargetTypeTest52.java
4619 // Is there anything to do?
4620 repeat = false;
4621 } else {
4622 Assert.error("Unexpected tree: " + enclTr + " with kind: " + enclTr.getKind() +
4623 " within: "+ errtree + " with kind: " + errtree.getKind());
4624 }
4625 }
4626 }
4627 };
4629 // <editor-fold desc="post-attribution visitor">
4631 /**
4632 * Handle missing types/symbols in an AST. This routine is useful when
4633 * the compiler has encountered some errors (which might have ended up
4634 * terminating attribution abruptly); if the compiler is used in fail-over
4635 * mode (e.g. by an IDE) and the AST contains semantic errors, this routine
4636 * prevents NPE to be progagated during subsequent compilation steps.
4637 */
4638 public void postAttr(JCTree tree) {
4639 new PostAttrAnalyzer().scan(tree);
4640 }
4642 class PostAttrAnalyzer extends TreeScanner {
4644 private void initTypeIfNeeded(JCTree that) {
4645 if (that.type == null) {
4646 that.type = syms.unknownType;
4647 }
4648 }
4650 @Override
4651 public void scan(JCTree tree) {
4652 if (tree == null) return;
4653 if (tree instanceof JCExpression) {
4654 initTypeIfNeeded(tree);
4655 }
4656 super.scan(tree);
4657 }
4659 @Override
4660 public void visitIdent(JCIdent that) {
4661 if (that.sym == null) {
4662 that.sym = syms.unknownSymbol;
4663 }
4664 }
4666 @Override
4667 public void visitSelect(JCFieldAccess that) {
4668 if (that.sym == null) {
4669 that.sym = syms.unknownSymbol;
4670 }
4671 super.visitSelect(that);
4672 }
4674 @Override
4675 public void visitClassDef(JCClassDecl that) {
4676 initTypeIfNeeded(that);
4677 if (that.sym == null) {
4678 that.sym = new ClassSymbol(0, that.name, that.type, syms.noSymbol);
4679 }
4680 super.visitClassDef(that);
4681 }
4683 @Override
4684 public void visitMethodDef(JCMethodDecl that) {
4685 initTypeIfNeeded(that);
4686 if (that.sym == null) {
4687 that.sym = new MethodSymbol(0, that.name, that.type, syms.noSymbol);
4688 }
4689 super.visitMethodDef(that);
4690 }
4692 @Override
4693 public void visitVarDef(JCVariableDecl that) {
4694 initTypeIfNeeded(that);
4695 if (that.sym == null) {
4696 that.sym = new VarSymbol(0, that.name, that.type, syms.noSymbol);
4697 that.sym.adr = 0;
4698 }
4699 super.visitVarDef(that);
4700 }
4702 @Override
4703 public void visitNewClass(JCNewClass that) {
4704 if (that.constructor == null) {
4705 that.constructor = new MethodSymbol(0, names.init, syms.unknownType, syms.noSymbol);
4706 }
4707 if (that.constructorType == null) {
4708 that.constructorType = syms.unknownType;
4709 }
4710 super.visitNewClass(that);
4711 }
4713 @Override
4714 public void visitAssignop(JCAssignOp that) {
4715 if (that.operator == null)
4716 that.operator = new OperatorSymbol(names.empty, syms.unknownType, -1, syms.noSymbol);
4717 super.visitAssignop(that);
4718 }
4720 @Override
4721 public void visitBinary(JCBinary that) {
4722 if (that.operator == null)
4723 that.operator = new OperatorSymbol(names.empty, syms.unknownType, -1, syms.noSymbol);
4724 super.visitBinary(that);
4725 }
4727 @Override
4728 public void visitUnary(JCUnary that) {
4729 if (that.operator == null)
4730 that.operator = new OperatorSymbol(names.empty, syms.unknownType, -1, syms.noSymbol);
4731 super.visitUnary(that);
4732 }
4734 @Override
4735 public void visitLambda(JCLambda that) {
4736 super.visitLambda(that);
4737 if (that.targets == null) {
4738 that.targets = List.nil();
4739 }
4740 }
4742 @Override
4743 public void visitReference(JCMemberReference that) {
4744 super.visitReference(that);
4745 if (that.sym == null) {
4746 that.sym = new MethodSymbol(0, names.empty, syms.unknownType, syms.noSymbol);
4747 }
4748 if (that.targets == null) {
4749 that.targets = List.nil();
4750 }
4751 }
4752 }
4753 // </editor-fold>
4754 }