Mon, 02 Sep 2013 22:38:36 +0100
8016177: structural most specific and stuckness
Reviewed-by: jjg, vromero
Contributed-by: maurizio.cimadamore@oracle.com
1 /*
2 * Copyright (c) 1999, 2013, Oracle and/or its affiliates. All rights reserved.
3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
4 *
5 * This code is free software; you can redistribute it and/or modify it
6 * under the terms of the GNU General Public License version 2 only, as
7 * published by the Free Software Foundation. Oracle designates this
8 * particular file as subject to the "Classpath" exception as provided
9 * by Oracle in the LICENSE file that accompanied this code.
10 *
11 * This code is distributed in the hope that it will be useful, but WITHOUT
12 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
13 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
14 * version 2 for more details (a copy is included in the LICENSE file that
15 * accompanied this code).
16 *
17 * You should have received a copy of the GNU General Public License version
18 * 2 along with this work; if not, write to the Free Software Foundation,
19 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
20 *
21 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
22 * or visit www.oracle.com if you need additional information or have any
23 * questions.
24 */
26 package com.sun.tools.javac.comp;
28 import java.util.*;
30 import javax.lang.model.element.ElementKind;
31 import javax.lang.model.type.TypeKind;
32 import javax.tools.JavaFileObject;
34 import com.sun.source.tree.IdentifierTree;
35 import com.sun.source.tree.MemberReferenceTree.ReferenceMode;
36 import com.sun.source.tree.MemberSelectTree;
37 import com.sun.source.tree.TreeVisitor;
38 import com.sun.source.util.SimpleTreeVisitor;
39 import com.sun.tools.javac.code.*;
40 import com.sun.tools.javac.code.Lint.LintCategory;
41 import com.sun.tools.javac.code.Symbol.*;
42 import com.sun.tools.javac.code.Type.*;
43 import com.sun.tools.javac.comp.Check.CheckContext;
44 import com.sun.tools.javac.comp.DeferredAttr.AttrMode;
45 import com.sun.tools.javac.comp.Infer.InferenceContext;
46 import com.sun.tools.javac.comp.Infer.FreeTypeListener;
47 import com.sun.tools.javac.jvm.*;
48 import com.sun.tools.javac.tree.*;
49 import com.sun.tools.javac.tree.JCTree.*;
50 import com.sun.tools.javac.tree.JCTree.JCPolyExpression.*;
51 import com.sun.tools.javac.util.*;
52 import com.sun.tools.javac.util.JCDiagnostic.DiagnosticPosition;
53 import com.sun.tools.javac.util.List;
54 import static com.sun.tools.javac.code.Flags.*;
55 import static com.sun.tools.javac.code.Flags.ANNOTATION;
56 import static com.sun.tools.javac.code.Flags.BLOCK;
57 import static com.sun.tools.javac.code.Kinds.*;
58 import static com.sun.tools.javac.code.Kinds.ERRONEOUS;
59 import static com.sun.tools.javac.code.TypeTag.*;
60 import static com.sun.tools.javac.code.TypeTag.WILDCARD;
61 import static com.sun.tools.javac.tree.JCTree.Tag.*;
63 /** This is the main context-dependent analysis phase in GJC. It
64 * encompasses name resolution, type checking and constant folding as
65 * subtasks. Some subtasks involve auxiliary classes.
66 * @see Check
67 * @see Resolve
68 * @see ConstFold
69 * @see Infer
70 *
71 * <p><b>This is NOT part of any supported API.
72 * If you write code that depends on this, you do so at your own risk.
73 * This code and its internal interfaces are subject to change or
74 * deletion without notice.</b>
75 */
76 public class Attr extends JCTree.Visitor {
77 protected static final Context.Key<Attr> attrKey =
78 new Context.Key<Attr>();
80 final Names names;
81 final Log log;
82 final Symtab syms;
83 final Resolve rs;
84 final Infer infer;
85 final DeferredAttr deferredAttr;
86 final Check chk;
87 final Flow flow;
88 final MemberEnter memberEnter;
89 final TreeMaker make;
90 final ConstFold cfolder;
91 final Enter enter;
92 final Target target;
93 final Types types;
94 final JCDiagnostic.Factory diags;
95 final Annotate annotate;
96 final DeferredLintHandler deferredLintHandler;
98 public static Attr instance(Context context) {
99 Attr instance = context.get(attrKey);
100 if (instance == null)
101 instance = new Attr(context);
102 return instance;
103 }
105 protected Attr(Context context) {
106 context.put(attrKey, this);
108 names = Names.instance(context);
109 log = Log.instance(context);
110 syms = Symtab.instance(context);
111 rs = Resolve.instance(context);
112 chk = Check.instance(context);
113 flow = Flow.instance(context);
114 memberEnter = MemberEnter.instance(context);
115 make = TreeMaker.instance(context);
116 enter = Enter.instance(context);
117 infer = Infer.instance(context);
118 deferredAttr = DeferredAttr.instance(context);
119 cfolder = ConstFold.instance(context);
120 target = Target.instance(context);
121 types = Types.instance(context);
122 diags = JCDiagnostic.Factory.instance(context);
123 annotate = Annotate.instance(context);
124 deferredLintHandler = DeferredLintHandler.instance(context);
126 Options options = Options.instance(context);
128 Source source = Source.instance(context);
129 allowGenerics = source.allowGenerics();
130 allowVarargs = source.allowVarargs();
131 allowEnums = source.allowEnums();
132 allowBoxing = source.allowBoxing();
133 allowCovariantReturns = source.allowCovariantReturns();
134 allowAnonOuterThis = source.allowAnonOuterThis();
135 allowStringsInSwitch = source.allowStringsInSwitch();
136 allowPoly = source.allowPoly();
137 allowTypeAnnos = source.allowTypeAnnotations();
138 allowLambda = source.allowLambda();
139 allowDefaultMethods = source.allowDefaultMethods();
140 sourceName = source.name;
141 relax = (options.isSet("-retrofit") ||
142 options.isSet("-relax"));
143 findDiamonds = options.get("findDiamond") != null &&
144 source.allowDiamond();
145 useBeforeDeclarationWarning = options.isSet("useBeforeDeclarationWarning");
146 identifyLambdaCandidate = options.getBoolean("identifyLambdaCandidate", false);
148 statInfo = new ResultInfo(NIL, Type.noType);
149 varInfo = new ResultInfo(VAR, Type.noType);
150 unknownExprInfo = new ResultInfo(VAL, Type.noType);
151 unknownAnyPolyInfo = new ResultInfo(VAL, Infer.anyPoly);
152 unknownTypeInfo = new ResultInfo(TYP, Type.noType);
153 unknownTypeExprInfo = new ResultInfo(Kinds.TYP | Kinds.VAL, Type.noType);
154 recoveryInfo = new RecoveryInfo(deferredAttr.emptyDeferredAttrContext);
155 }
157 /** Switch: relax some constraints for retrofit mode.
158 */
159 boolean relax;
161 /** Switch: support target-typing inference
162 */
163 boolean allowPoly;
165 /** Switch: support type annotations.
166 */
167 boolean allowTypeAnnos;
169 /** Switch: support generics?
170 */
171 boolean allowGenerics;
173 /** Switch: allow variable-arity methods.
174 */
175 boolean allowVarargs;
177 /** Switch: support enums?
178 */
179 boolean allowEnums;
181 /** Switch: support boxing and unboxing?
182 */
183 boolean allowBoxing;
185 /** Switch: support covariant result types?
186 */
187 boolean allowCovariantReturns;
189 /** Switch: support lambda expressions ?
190 */
191 boolean allowLambda;
193 /** Switch: support default methods ?
194 */
195 boolean allowDefaultMethods;
197 /** Switch: allow references to surrounding object from anonymous
198 * objects during constructor call?
199 */
200 boolean allowAnonOuterThis;
202 /** Switch: generates a warning if diamond can be safely applied
203 * to a given new expression
204 */
205 boolean findDiamonds;
207 /**
208 * Internally enables/disables diamond finder feature
209 */
210 static final boolean allowDiamondFinder = true;
212 /**
213 * Switch: warn about use of variable before declaration?
214 * RFE: 6425594
215 */
216 boolean useBeforeDeclarationWarning;
218 /**
219 * Switch: generate warnings whenever an anonymous inner class that is convertible
220 * to a lambda expression is found
221 */
222 boolean identifyLambdaCandidate;
224 /**
225 * Switch: allow strings in switch?
226 */
227 boolean allowStringsInSwitch;
229 /**
230 * Switch: name of source level; used for error reporting.
231 */
232 String sourceName;
234 /** Check kind and type of given tree against protokind and prototype.
235 * If check succeeds, store type in tree and return it.
236 * If check fails, store errType in tree and return it.
237 * No checks are performed if the prototype is a method type.
238 * It is not necessary in this case since we know that kind and type
239 * are correct.
240 *
241 * @param tree The tree whose kind and type is checked
242 * @param ownkind The computed kind of the tree
243 * @param resultInfo The expected result of the tree
244 */
245 Type check(final JCTree tree, final Type found, final int ownkind, final ResultInfo resultInfo) {
246 InferenceContext inferenceContext = resultInfo.checkContext.inferenceContext();
247 Type owntype = found;
248 if (!owntype.hasTag(ERROR) && !resultInfo.pt.hasTag(METHOD) && !resultInfo.pt.hasTag(FORALL)) {
249 if (allowPoly && inferenceContext.free(found)) {
250 inferenceContext.addFreeTypeListener(List.of(found, resultInfo.pt), new FreeTypeListener() {
251 @Override
252 public void typesInferred(InferenceContext inferenceContext) {
253 ResultInfo pendingResult =
254 resultInfo.dup(inferenceContext.asInstType(resultInfo.pt));
255 check(tree, inferenceContext.asInstType(found), ownkind, pendingResult);
256 }
257 });
258 return tree.type = resultInfo.pt;
259 } else {
260 if ((ownkind & ~resultInfo.pkind) == 0) {
261 owntype = resultInfo.check(tree, owntype);
262 } else {
263 log.error(tree.pos(), "unexpected.type",
264 kindNames(resultInfo.pkind),
265 kindName(ownkind));
266 owntype = types.createErrorType(owntype);
267 }
268 }
269 }
270 tree.type = owntype;
271 return owntype;
272 }
274 /** Is given blank final variable assignable, i.e. in a scope where it
275 * may be assigned to even though it is final?
276 * @param v The blank final variable.
277 * @param env The current environment.
278 */
279 boolean isAssignableAsBlankFinal(VarSymbol v, Env<AttrContext> env) {
280 Symbol owner = owner(env);
281 // owner refers to the innermost variable, method or
282 // initializer block declaration at this point.
283 return
284 v.owner == owner
285 ||
286 ((owner.name == names.init || // i.e. we are in a constructor
287 owner.kind == VAR || // i.e. we are in a variable initializer
288 (owner.flags() & BLOCK) != 0) // i.e. we are in an initializer block
289 &&
290 v.owner == owner.owner
291 &&
292 ((v.flags() & STATIC) != 0) == Resolve.isStatic(env));
293 }
295 /**
296 * Return the innermost enclosing owner symbol in a given attribution context
297 */
298 Symbol owner(Env<AttrContext> env) {
299 while (true) {
300 switch (env.tree.getTag()) {
301 case VARDEF:
302 //a field can be owner
303 VarSymbol vsym = ((JCVariableDecl)env.tree).sym;
304 if (vsym.owner.kind == TYP) {
305 return vsym;
306 }
307 break;
308 case METHODDEF:
309 //method def is always an owner
310 return ((JCMethodDecl)env.tree).sym;
311 case CLASSDEF:
312 //class def is always an owner
313 return ((JCClassDecl)env.tree).sym;
314 case LAMBDA:
315 //a lambda is an owner - return a fresh synthetic method symbol
316 return new MethodSymbol(0, names.empty, null, syms.methodClass);
317 case BLOCK:
318 //static/instance init blocks are owner
319 Symbol blockSym = env.info.scope.owner;
320 if ((blockSym.flags() & BLOCK) != 0) {
321 return blockSym;
322 }
323 break;
324 case TOPLEVEL:
325 //toplevel is always an owner (for pkge decls)
326 return env.info.scope.owner;
327 }
328 Assert.checkNonNull(env.next);
329 env = env.next;
330 }
331 }
333 /** Check that variable can be assigned to.
334 * @param pos The current source code position.
335 * @param v The assigned varaible
336 * @param base If the variable is referred to in a Select, the part
337 * to the left of the `.', null otherwise.
338 * @param env The current environment.
339 */
340 void checkAssignable(DiagnosticPosition pos, VarSymbol v, JCTree base, Env<AttrContext> env) {
341 if ((v.flags() & FINAL) != 0 &&
342 ((v.flags() & HASINIT) != 0
343 ||
344 !((base == null ||
345 (base.hasTag(IDENT) && TreeInfo.name(base) == names._this)) &&
346 isAssignableAsBlankFinal(v, env)))) {
347 if (v.isResourceVariable()) { //TWR resource
348 log.error(pos, "try.resource.may.not.be.assigned", v);
349 } else {
350 log.error(pos, "cant.assign.val.to.final.var", v);
351 }
352 }
353 }
355 /** Does tree represent a static reference to an identifier?
356 * It is assumed that tree is either a SELECT or an IDENT.
357 * We have to weed out selects from non-type names here.
358 * @param tree The candidate tree.
359 */
360 boolean isStaticReference(JCTree tree) {
361 if (tree.hasTag(SELECT)) {
362 Symbol lsym = TreeInfo.symbol(((JCFieldAccess) tree).selected);
363 if (lsym == null || lsym.kind != TYP) {
364 return false;
365 }
366 }
367 return true;
368 }
370 /** Is this symbol a type?
371 */
372 static boolean isType(Symbol sym) {
373 return sym != null && sym.kind == TYP;
374 }
376 /** The current `this' symbol.
377 * @param env The current environment.
378 */
379 Symbol thisSym(DiagnosticPosition pos, Env<AttrContext> env) {
380 return rs.resolveSelf(pos, env, env.enclClass.sym, names._this);
381 }
383 /** Attribute a parsed identifier.
384 * @param tree Parsed identifier name
385 * @param topLevel The toplevel to use
386 */
387 public Symbol attribIdent(JCTree tree, JCCompilationUnit topLevel) {
388 Env<AttrContext> localEnv = enter.topLevelEnv(topLevel);
389 localEnv.enclClass = make.ClassDef(make.Modifiers(0),
390 syms.errSymbol.name,
391 null, null, null, null);
392 localEnv.enclClass.sym = syms.errSymbol;
393 return tree.accept(identAttributer, localEnv);
394 }
395 // where
396 private TreeVisitor<Symbol,Env<AttrContext>> identAttributer = new IdentAttributer();
397 private class IdentAttributer extends SimpleTreeVisitor<Symbol,Env<AttrContext>> {
398 @Override
399 public Symbol visitMemberSelect(MemberSelectTree node, Env<AttrContext> env) {
400 Symbol site = visit(node.getExpression(), env);
401 if (site.kind == ERR || site.kind == ABSENT_TYP)
402 return site;
403 Name name = (Name)node.getIdentifier();
404 if (site.kind == PCK) {
405 env.toplevel.packge = (PackageSymbol)site;
406 return rs.findIdentInPackage(env, (TypeSymbol)site, name, TYP | PCK);
407 } else {
408 env.enclClass.sym = (ClassSymbol)site;
409 return rs.findMemberType(env, site.asType(), name, (TypeSymbol)site);
410 }
411 }
413 @Override
414 public Symbol visitIdentifier(IdentifierTree node, Env<AttrContext> env) {
415 return rs.findIdent(env, (Name)node.getName(), TYP | PCK);
416 }
417 }
419 public Type coerce(Type etype, Type ttype) {
420 return cfolder.coerce(etype, ttype);
421 }
423 public Type attribType(JCTree node, TypeSymbol sym) {
424 Env<AttrContext> env = enter.typeEnvs.get(sym);
425 Env<AttrContext> localEnv = env.dup(node, env.info.dup());
426 return attribTree(node, localEnv, unknownTypeInfo);
427 }
429 public Type attribImportQualifier(JCImport tree, Env<AttrContext> env) {
430 // Attribute qualifying package or class.
431 JCFieldAccess s = (JCFieldAccess)tree.qualid;
432 return attribTree(s.selected,
433 env,
434 new ResultInfo(tree.staticImport ? TYP : (TYP | PCK),
435 Type.noType));
436 }
438 public Env<AttrContext> attribExprToTree(JCTree expr, Env<AttrContext> env, JCTree tree) {
439 breakTree = tree;
440 JavaFileObject prev = log.useSource(env.toplevel.sourcefile);
441 try {
442 attribExpr(expr, env);
443 } catch (BreakAttr b) {
444 return b.env;
445 } catch (AssertionError ae) {
446 if (ae.getCause() instanceof BreakAttr) {
447 return ((BreakAttr)(ae.getCause())).env;
448 } else {
449 throw ae;
450 }
451 } finally {
452 breakTree = null;
453 log.useSource(prev);
454 }
455 return env;
456 }
458 public Env<AttrContext> attribStatToTree(JCTree stmt, Env<AttrContext> env, JCTree tree) {
459 breakTree = tree;
460 JavaFileObject prev = log.useSource(env.toplevel.sourcefile);
461 try {
462 attribStat(stmt, env);
463 } catch (BreakAttr b) {
464 return b.env;
465 } catch (AssertionError ae) {
466 if (ae.getCause() instanceof BreakAttr) {
467 return ((BreakAttr)(ae.getCause())).env;
468 } else {
469 throw ae;
470 }
471 } finally {
472 breakTree = null;
473 log.useSource(prev);
474 }
475 return env;
476 }
478 private JCTree breakTree = null;
480 private static class BreakAttr extends RuntimeException {
481 static final long serialVersionUID = -6924771130405446405L;
482 private Env<AttrContext> env;
483 private BreakAttr(Env<AttrContext> env) {
484 this.env = env;
485 }
486 }
488 class ResultInfo {
489 final int pkind;
490 final Type pt;
491 final CheckContext checkContext;
493 ResultInfo(int pkind, Type pt) {
494 this(pkind, pt, chk.basicHandler);
495 }
497 protected ResultInfo(int pkind, Type pt, CheckContext checkContext) {
498 this.pkind = pkind;
499 this.pt = pt;
500 this.checkContext = checkContext;
501 }
503 protected Type check(final DiagnosticPosition pos, final Type found) {
504 return chk.checkType(pos, found, pt, checkContext);
505 }
507 protected ResultInfo dup(Type newPt) {
508 return new ResultInfo(pkind, newPt, checkContext);
509 }
511 protected ResultInfo dup(CheckContext newContext) {
512 return new ResultInfo(pkind, pt, newContext);
513 }
514 }
516 class RecoveryInfo extends ResultInfo {
518 public RecoveryInfo(final DeferredAttr.DeferredAttrContext deferredAttrContext) {
519 super(Kinds.VAL, Type.recoveryType, new Check.NestedCheckContext(chk.basicHandler) {
520 @Override
521 public DeferredAttr.DeferredAttrContext deferredAttrContext() {
522 return deferredAttrContext;
523 }
524 @Override
525 public boolean compatible(Type found, Type req, Warner warn) {
526 return true;
527 }
528 @Override
529 public void report(DiagnosticPosition pos, JCDiagnostic details) {
530 chk.basicHandler.report(pos, details);
531 }
532 });
533 }
534 }
536 final ResultInfo statInfo;
537 final ResultInfo varInfo;
538 final ResultInfo unknownAnyPolyInfo;
539 final ResultInfo unknownExprInfo;
540 final ResultInfo unknownTypeInfo;
541 final ResultInfo unknownTypeExprInfo;
542 final ResultInfo recoveryInfo;
544 Type pt() {
545 return resultInfo.pt;
546 }
548 int pkind() {
549 return resultInfo.pkind;
550 }
552 /* ************************************************************************
553 * Visitor methods
554 *************************************************************************/
556 /** Visitor argument: the current environment.
557 */
558 Env<AttrContext> env;
560 /** Visitor argument: the currently expected attribution result.
561 */
562 ResultInfo resultInfo;
564 /** Visitor result: the computed type.
565 */
566 Type result;
568 /** Visitor method: attribute a tree, catching any completion failure
569 * exceptions. Return the tree's type.
570 *
571 * @param tree The tree to be visited.
572 * @param env The environment visitor argument.
573 * @param resultInfo The result info visitor argument.
574 */
575 Type attribTree(JCTree tree, Env<AttrContext> env, ResultInfo resultInfo) {
576 Env<AttrContext> prevEnv = this.env;
577 ResultInfo prevResult = this.resultInfo;
578 try {
579 this.env = env;
580 this.resultInfo = resultInfo;
581 tree.accept(this);
582 if (tree == breakTree &&
583 resultInfo.checkContext.deferredAttrContext().mode == AttrMode.CHECK) {
584 throw new BreakAttr(copyEnv(env));
585 }
586 return result;
587 } catch (CompletionFailure ex) {
588 tree.type = syms.errType;
589 return chk.completionError(tree.pos(), ex);
590 } finally {
591 this.env = prevEnv;
592 this.resultInfo = prevResult;
593 }
594 }
596 Env<AttrContext> copyEnv(Env<AttrContext> env) {
597 Env<AttrContext> newEnv =
598 env.dup(env.tree, env.info.dup(copyScope(env.info.scope)));
599 if (newEnv.outer != null) {
600 newEnv.outer = copyEnv(newEnv.outer);
601 }
602 return newEnv;
603 }
605 Scope copyScope(Scope sc) {
606 Scope newScope = new Scope(sc.owner);
607 List<Symbol> elemsList = List.nil();
608 while (sc != null) {
609 for (Scope.Entry e = sc.elems ; e != null ; e = e.sibling) {
610 elemsList = elemsList.prepend(e.sym);
611 }
612 sc = sc.next;
613 }
614 for (Symbol s : elemsList) {
615 newScope.enter(s);
616 }
617 return newScope;
618 }
620 /** Derived visitor method: attribute an expression tree.
621 */
622 public Type attribExpr(JCTree tree, Env<AttrContext> env, Type pt) {
623 return attribTree(tree, env, new ResultInfo(VAL, !pt.hasTag(ERROR) ? pt : Type.noType));
624 }
626 /** Derived visitor method: attribute an expression tree with
627 * no constraints on the computed type.
628 */
629 public Type attribExpr(JCTree tree, Env<AttrContext> env) {
630 return attribTree(tree, env, unknownExprInfo);
631 }
633 /** Derived visitor method: attribute a type tree.
634 */
635 public Type attribType(JCTree tree, Env<AttrContext> env) {
636 Type result = attribType(tree, env, Type.noType);
637 return result;
638 }
640 /** Derived visitor method: attribute a type tree.
641 */
642 Type attribType(JCTree tree, Env<AttrContext> env, Type pt) {
643 Type result = attribTree(tree, env, new ResultInfo(TYP, pt));
644 return result;
645 }
647 /** Derived visitor method: attribute a statement or definition tree.
648 */
649 public Type attribStat(JCTree tree, Env<AttrContext> env) {
650 return attribTree(tree, env, statInfo);
651 }
653 /** Attribute a list of expressions, returning a list of types.
654 */
655 List<Type> attribExprs(List<JCExpression> trees, Env<AttrContext> env, Type pt) {
656 ListBuffer<Type> ts = new ListBuffer<Type>();
657 for (List<JCExpression> l = trees; l.nonEmpty(); l = l.tail)
658 ts.append(attribExpr(l.head, env, pt));
659 return ts.toList();
660 }
662 /** Attribute a list of statements, returning nothing.
663 */
664 <T extends JCTree> void attribStats(List<T> trees, Env<AttrContext> env) {
665 for (List<T> l = trees; l.nonEmpty(); l = l.tail)
666 attribStat(l.head, env);
667 }
669 /** Attribute the arguments in a method call, returning the method kind.
670 */
671 int attribArgs(List<JCExpression> trees, Env<AttrContext> env, ListBuffer<Type> argtypes) {
672 int kind = VAL;
673 for (JCExpression arg : trees) {
674 Type argtype;
675 if (allowPoly && deferredAttr.isDeferred(env, arg)) {
676 argtype = deferredAttr.new DeferredType(arg, env);
677 kind |= POLY;
678 } else {
679 argtype = chk.checkNonVoid(arg, attribTree(arg, env, unknownAnyPolyInfo));
680 }
681 argtypes.append(argtype);
682 }
683 return kind;
684 }
686 /** Attribute a type argument list, returning a list of types.
687 * Caller is responsible for calling checkRefTypes.
688 */
689 List<Type> attribAnyTypes(List<JCExpression> trees, Env<AttrContext> env) {
690 ListBuffer<Type> argtypes = new ListBuffer<Type>();
691 for (List<JCExpression> l = trees; l.nonEmpty(); l = l.tail)
692 argtypes.append(attribType(l.head, env));
693 return argtypes.toList();
694 }
696 /** Attribute a type argument list, returning a list of types.
697 * Check that all the types are references.
698 */
699 List<Type> attribTypes(List<JCExpression> trees, Env<AttrContext> env) {
700 List<Type> types = attribAnyTypes(trees, env);
701 return chk.checkRefTypes(trees, types);
702 }
704 /**
705 * Attribute type variables (of generic classes or methods).
706 * Compound types are attributed later in attribBounds.
707 * @param typarams the type variables to enter
708 * @param env the current environment
709 */
710 void attribTypeVariables(List<JCTypeParameter> typarams, Env<AttrContext> env) {
711 for (JCTypeParameter tvar : typarams) {
712 TypeVar a = (TypeVar)tvar.type;
713 a.tsym.flags_field |= UNATTRIBUTED;
714 a.bound = Type.noType;
715 if (!tvar.bounds.isEmpty()) {
716 List<Type> bounds = List.of(attribType(tvar.bounds.head, env));
717 for (JCExpression bound : tvar.bounds.tail)
718 bounds = bounds.prepend(attribType(bound, env));
719 types.setBounds(a, bounds.reverse());
720 } else {
721 // if no bounds are given, assume a single bound of
722 // java.lang.Object.
723 types.setBounds(a, List.of(syms.objectType));
724 }
725 a.tsym.flags_field &= ~UNATTRIBUTED;
726 }
727 for (JCTypeParameter tvar : typarams) {
728 chk.checkNonCyclic(tvar.pos(), (TypeVar)tvar.type);
729 }
730 }
732 /**
733 * Attribute the type references in a list of annotations.
734 */
735 void attribAnnotationTypes(List<JCAnnotation> annotations,
736 Env<AttrContext> env) {
737 for (List<JCAnnotation> al = annotations; al.nonEmpty(); al = al.tail) {
738 JCAnnotation a = al.head;
739 attribType(a.annotationType, env);
740 }
741 }
743 /**
744 * Attribute a "lazy constant value".
745 * @param env The env for the const value
746 * @param initializer The initializer for the const value
747 * @param type The expected type, or null
748 * @see VarSymbol#setLazyConstValue
749 */
750 public Object attribLazyConstantValue(Env<AttrContext> env,
751 JCTree.JCExpression initializer,
752 Type type) {
754 /* When this env was created, it didn't have the correct lint nor had
755 * annotations has been processed.
756 * But now at this phase we have already processed annotations and the
757 * correct lint must have been set in chk, so we should use that one to
758 * attribute the initializer.
759 */
760 Lint prevLint = env.info.lint;
761 env.info.lint = chk.getLint();
763 JavaFileObject prevSource = log.useSource(env.toplevel.sourcefile);
765 try {
766 // Use null as symbol to not attach the type annotation to any symbol.
767 // The initializer will later also be visited and then we'll attach
768 // to the symbol.
769 // This prevents having multiple type annotations, just because of
770 // lazy constant value evaluation.
771 memberEnter.typeAnnotate(initializer, env, null);
772 annotate.flush();
773 Type itype = attribExpr(initializer, env, type);
774 if (itype.constValue() != null) {
775 return coerce(itype, type).constValue();
776 } else {
777 return null;
778 }
779 } finally {
780 env.info.lint = prevLint;
781 log.useSource(prevSource);
782 }
783 }
785 /** Attribute type reference in an `extends' or `implements' clause.
786 * Supertypes of anonymous inner classes are usually already attributed.
787 *
788 * @param tree The tree making up the type reference.
789 * @param env The environment current at the reference.
790 * @param classExpected true if only a class is expected here.
791 * @param interfaceExpected true if only an interface is expected here.
792 */
793 Type attribBase(JCTree tree,
794 Env<AttrContext> env,
795 boolean classExpected,
796 boolean interfaceExpected,
797 boolean checkExtensible) {
798 Type t = tree.type != null ?
799 tree.type :
800 attribType(tree, env);
801 return checkBase(t, tree, env, classExpected, interfaceExpected, checkExtensible);
802 }
803 Type checkBase(Type t,
804 JCTree tree,
805 Env<AttrContext> env,
806 boolean classExpected,
807 boolean interfaceExpected,
808 boolean checkExtensible) {
809 if (t.isErroneous())
810 return t;
811 if (t.hasTag(TYPEVAR) && !classExpected && !interfaceExpected) {
812 // check that type variable is already visible
813 if (t.getUpperBound() == null) {
814 log.error(tree.pos(), "illegal.forward.ref");
815 return types.createErrorType(t);
816 }
817 } else {
818 t = chk.checkClassType(tree.pos(), t, checkExtensible|!allowGenerics);
819 }
820 if (interfaceExpected && (t.tsym.flags() & INTERFACE) == 0) {
821 log.error(tree.pos(), "intf.expected.here");
822 // return errType is necessary since otherwise there might
823 // be undetected cycles which cause attribution to loop
824 return types.createErrorType(t);
825 } else if (checkExtensible &&
826 classExpected &&
827 (t.tsym.flags() & INTERFACE) != 0) {
828 log.error(tree.pos(), "no.intf.expected.here");
829 return types.createErrorType(t);
830 }
831 if (checkExtensible &&
832 ((t.tsym.flags() & FINAL) != 0)) {
833 log.error(tree.pos(),
834 "cant.inherit.from.final", t.tsym);
835 }
836 chk.checkNonCyclic(tree.pos(), t);
837 return t;
838 }
840 Type attribIdentAsEnumType(Env<AttrContext> env, JCIdent id) {
841 Assert.check((env.enclClass.sym.flags() & ENUM) != 0);
842 id.type = env.info.scope.owner.type;
843 id.sym = env.info.scope.owner;
844 return id.type;
845 }
847 public void visitClassDef(JCClassDecl tree) {
848 // Local classes have not been entered yet, so we need to do it now:
849 if ((env.info.scope.owner.kind & (VAR | MTH)) != 0)
850 enter.classEnter(tree, env);
852 ClassSymbol c = tree.sym;
853 if (c == null) {
854 // exit in case something drastic went wrong during enter.
855 result = null;
856 } else {
857 // make sure class has been completed:
858 c.complete();
860 // If this class appears as an anonymous class
861 // in a superclass constructor call where
862 // no explicit outer instance is given,
863 // disable implicit outer instance from being passed.
864 // (This would be an illegal access to "this before super").
865 if (env.info.isSelfCall &&
866 env.tree.hasTag(NEWCLASS) &&
867 ((JCNewClass) env.tree).encl == null)
868 {
869 c.flags_field |= NOOUTERTHIS;
870 }
871 attribClass(tree.pos(), c);
872 result = tree.type = c.type;
873 }
874 }
876 public void visitMethodDef(JCMethodDecl tree) {
877 MethodSymbol m = tree.sym;
878 boolean isDefaultMethod = (m.flags() & DEFAULT) != 0;
880 Lint lint = env.info.lint.augment(m);
881 Lint prevLint = chk.setLint(lint);
882 MethodSymbol prevMethod = chk.setMethod(m);
883 try {
884 deferredLintHandler.flush(tree.pos());
885 chk.checkDeprecatedAnnotation(tree.pos(), m);
888 // Create a new environment with local scope
889 // for attributing the method.
890 Env<AttrContext> localEnv = memberEnter.methodEnv(tree, env);
891 localEnv.info.lint = lint;
893 attribStats(tree.typarams, localEnv);
895 // If we override any other methods, check that we do so properly.
896 // JLS ???
897 if (m.isStatic()) {
898 chk.checkHideClashes(tree.pos(), env.enclClass.type, m);
899 } else {
900 chk.checkOverrideClashes(tree.pos(), env.enclClass.type, m);
901 }
902 chk.checkOverride(tree, m);
904 if (isDefaultMethod && types.overridesObjectMethod(m.enclClass(), m)) {
905 log.error(tree, "default.overrides.object.member", m.name, Kinds.kindName(m.location()), m.location());
906 }
908 // Enter all type parameters into the local method scope.
909 for (List<JCTypeParameter> l = tree.typarams; l.nonEmpty(); l = l.tail)
910 localEnv.info.scope.enterIfAbsent(l.head.type.tsym);
912 ClassSymbol owner = env.enclClass.sym;
913 if ((owner.flags() & ANNOTATION) != 0 &&
914 tree.params.nonEmpty())
915 log.error(tree.params.head.pos(),
916 "intf.annotation.members.cant.have.params");
918 // Attribute all value parameters.
919 for (List<JCVariableDecl> l = tree.params; l.nonEmpty(); l = l.tail) {
920 attribStat(l.head, localEnv);
921 }
923 chk.checkVarargsMethodDecl(localEnv, tree);
925 // Check that type parameters are well-formed.
926 chk.validate(tree.typarams, localEnv);
928 // Check that result type is well-formed.
929 chk.validate(tree.restype, localEnv);
931 // Check that receiver type is well-formed.
932 if (tree.recvparam != null) {
933 // Use a new environment to check the receiver parameter.
934 // Otherwise I get "might not have been initialized" errors.
935 // Is there a better way?
936 Env<AttrContext> newEnv = memberEnter.methodEnv(tree, env);
937 attribType(tree.recvparam, newEnv);
938 chk.validate(tree.recvparam, newEnv);
939 }
941 // annotation method checks
942 if ((owner.flags() & ANNOTATION) != 0) {
943 // annotation method cannot have throws clause
944 if (tree.thrown.nonEmpty()) {
945 log.error(tree.thrown.head.pos(),
946 "throws.not.allowed.in.intf.annotation");
947 }
948 // annotation method cannot declare type-parameters
949 if (tree.typarams.nonEmpty()) {
950 log.error(tree.typarams.head.pos(),
951 "intf.annotation.members.cant.have.type.params");
952 }
953 // validate annotation method's return type (could be an annotation type)
954 chk.validateAnnotationType(tree.restype);
955 // ensure that annotation method does not clash with members of Object/Annotation
956 chk.validateAnnotationMethod(tree.pos(), m);
958 if (tree.defaultValue != null) {
959 // if default value is an annotation, check it is a well-formed
960 // annotation value (e.g. no duplicate values, no missing values, etc.)
961 chk.validateAnnotationTree(tree.defaultValue);
962 }
963 }
965 for (List<JCExpression> l = tree.thrown; l.nonEmpty(); l = l.tail)
966 chk.checkType(l.head.pos(), l.head.type, syms.throwableType);
968 if (tree.body == null) {
969 // Empty bodies are only allowed for
970 // abstract, native, or interface methods, or for methods
971 // in a retrofit signature class.
972 if (isDefaultMethod || (tree.sym.flags() & (ABSTRACT | NATIVE)) == 0 &&
973 !relax)
974 log.error(tree.pos(), "missing.meth.body.or.decl.abstract");
975 if (tree.defaultValue != null) {
976 if ((owner.flags() & ANNOTATION) == 0)
977 log.error(tree.pos(),
978 "default.allowed.in.intf.annotation.member");
979 }
980 } else if ((tree.sym.flags() & ABSTRACT) != 0 && !isDefaultMethod) {
981 if ((owner.flags() & INTERFACE) != 0) {
982 log.error(tree.body.pos(), "intf.meth.cant.have.body");
983 } else {
984 log.error(tree.pos(), "abstract.meth.cant.have.body");
985 }
986 } else if ((tree.mods.flags & NATIVE) != 0) {
987 log.error(tree.pos(), "native.meth.cant.have.body");
988 } else {
989 // Add an implicit super() call unless an explicit call to
990 // super(...) or this(...) is given
991 // or we are compiling class java.lang.Object.
992 if (tree.name == names.init && owner.type != syms.objectType) {
993 JCBlock body = tree.body;
994 if (body.stats.isEmpty() ||
995 !TreeInfo.isSelfCall(body.stats.head)) {
996 body.stats = body.stats.
997 prepend(memberEnter.SuperCall(make.at(body.pos),
998 List.<Type>nil(),
999 List.<JCVariableDecl>nil(),
1000 false));
1001 } else if ((env.enclClass.sym.flags() & ENUM) != 0 &&
1002 (tree.mods.flags & GENERATEDCONSTR) == 0 &&
1003 TreeInfo.isSuperCall(body.stats.head)) {
1004 // enum constructors are not allowed to call super
1005 // directly, so make sure there aren't any super calls
1006 // in enum constructors, except in the compiler
1007 // generated one.
1008 log.error(tree.body.stats.head.pos(),
1009 "call.to.super.not.allowed.in.enum.ctor",
1010 env.enclClass.sym);
1011 }
1012 }
1014 // Attribute all type annotations in the body
1015 memberEnter.typeAnnotate(tree.body, localEnv, m);
1016 annotate.flush();
1018 // Attribute method body.
1019 attribStat(tree.body, localEnv);
1020 }
1022 localEnv.info.scope.leave();
1023 result = tree.type = m.type;
1024 chk.validateAnnotations(tree.mods.annotations, m);
1025 }
1026 finally {
1027 chk.setLint(prevLint);
1028 chk.setMethod(prevMethod);
1029 }
1030 }
1032 public void visitVarDef(JCVariableDecl tree) {
1033 // Local variables have not been entered yet, so we need to do it now:
1034 if (env.info.scope.owner.kind == MTH) {
1035 if (tree.sym != null) {
1036 // parameters have already been entered
1037 env.info.scope.enter(tree.sym);
1038 } else {
1039 memberEnter.memberEnter(tree, env);
1040 annotate.flush();
1041 }
1042 } else {
1043 if (tree.init != null) {
1044 // Field initializer expression need to be entered.
1045 memberEnter.typeAnnotate(tree.init, env, tree.sym);
1046 annotate.flush();
1047 }
1048 }
1050 VarSymbol v = tree.sym;
1051 Lint lint = env.info.lint.augment(v);
1052 Lint prevLint = chk.setLint(lint);
1054 // Check that the variable's declared type is well-formed.
1055 boolean isImplicitLambdaParameter = env.tree.hasTag(LAMBDA) &&
1056 ((JCLambda)env.tree).paramKind == JCLambda.ParameterKind.IMPLICIT &&
1057 (tree.sym.flags() & PARAMETER) != 0;
1058 chk.validate(tree.vartype, env, !isImplicitLambdaParameter);
1059 deferredLintHandler.flush(tree.pos());
1061 try {
1062 chk.checkDeprecatedAnnotation(tree.pos(), v);
1064 if (tree.init != null) {
1065 if ((v.flags_field & FINAL) != 0 &&
1066 memberEnter.needsLazyConstValue(tree.init)) {
1067 // In this case, `v' is final. Ensure that it's initializer is
1068 // evaluated.
1069 v.getConstValue(); // ensure initializer is evaluated
1070 } else {
1071 // Attribute initializer in a new environment
1072 // with the declared variable as owner.
1073 // Check that initializer conforms to variable's declared type.
1074 Env<AttrContext> initEnv = memberEnter.initEnv(tree, env);
1075 initEnv.info.lint = lint;
1076 // In order to catch self-references, we set the variable's
1077 // declaration position to maximal possible value, effectively
1078 // marking the variable as undefined.
1079 initEnv.info.enclVar = v;
1080 attribExpr(tree.init, initEnv, v.type);
1081 }
1082 }
1083 result = tree.type = v.type;
1084 chk.validateAnnotations(tree.mods.annotations, v);
1085 }
1086 finally {
1087 chk.setLint(prevLint);
1088 }
1089 }
1091 public void visitSkip(JCSkip tree) {
1092 result = null;
1093 }
1095 public void visitBlock(JCBlock tree) {
1096 if (env.info.scope.owner.kind == TYP) {
1097 // Block is a static or instance initializer;
1098 // let the owner of the environment be a freshly
1099 // created BLOCK-method.
1100 Env<AttrContext> localEnv =
1101 env.dup(tree, env.info.dup(env.info.scope.dupUnshared()));
1102 localEnv.info.scope.owner =
1103 new MethodSymbol(tree.flags | BLOCK |
1104 env.info.scope.owner.flags() & STRICTFP, names.empty, null,
1105 env.info.scope.owner);
1106 if ((tree.flags & STATIC) != 0) localEnv.info.staticLevel++;
1108 // Attribute all type annotations in the block
1109 memberEnter.typeAnnotate(tree, localEnv, localEnv.info.scope.owner);
1110 annotate.flush();
1112 {
1113 // Store init and clinit type annotations with the ClassSymbol
1114 // to allow output in Gen.normalizeDefs.
1115 ClassSymbol cs = (ClassSymbol)env.info.scope.owner;
1116 List<Attribute.TypeCompound> tas = localEnv.info.scope.owner.getRawTypeAttributes();
1117 if ((tree.flags & STATIC) != 0) {
1118 cs.appendClassInitTypeAttributes(tas);
1119 } else {
1120 cs.appendInitTypeAttributes(tas);
1121 }
1122 }
1124 attribStats(tree.stats, localEnv);
1125 } else {
1126 // Create a new local environment with a local scope.
1127 Env<AttrContext> localEnv =
1128 env.dup(tree, env.info.dup(env.info.scope.dup()));
1129 try {
1130 attribStats(tree.stats, localEnv);
1131 } finally {
1132 localEnv.info.scope.leave();
1133 }
1134 }
1135 result = null;
1136 }
1138 public void visitDoLoop(JCDoWhileLoop tree) {
1139 attribStat(tree.body, env.dup(tree));
1140 attribExpr(tree.cond, env, syms.booleanType);
1141 result = null;
1142 }
1144 public void visitWhileLoop(JCWhileLoop tree) {
1145 attribExpr(tree.cond, env, syms.booleanType);
1146 attribStat(tree.body, env.dup(tree));
1147 result = null;
1148 }
1150 public void visitForLoop(JCForLoop tree) {
1151 Env<AttrContext> loopEnv =
1152 env.dup(env.tree, env.info.dup(env.info.scope.dup()));
1153 try {
1154 attribStats(tree.init, loopEnv);
1155 if (tree.cond != null) attribExpr(tree.cond, loopEnv, syms.booleanType);
1156 loopEnv.tree = tree; // before, we were not in loop!
1157 attribStats(tree.step, loopEnv);
1158 attribStat(tree.body, loopEnv);
1159 result = null;
1160 }
1161 finally {
1162 loopEnv.info.scope.leave();
1163 }
1164 }
1166 public void visitForeachLoop(JCEnhancedForLoop tree) {
1167 Env<AttrContext> loopEnv =
1168 env.dup(env.tree, env.info.dup(env.info.scope.dup()));
1169 try {
1170 //the Formal Parameter of a for-each loop is not in the scope when
1171 //attributing the for-each expression; we mimick this by attributing
1172 //the for-each expression first (against original scope).
1173 Type exprType = types.upperBound(attribExpr(tree.expr, loopEnv));
1174 attribStat(tree.var, loopEnv);
1175 chk.checkNonVoid(tree.pos(), exprType);
1176 Type elemtype = types.elemtype(exprType); // perhaps expr is an array?
1177 if (elemtype == null) {
1178 // or perhaps expr implements Iterable<T>?
1179 Type base = types.asSuper(exprType, syms.iterableType.tsym);
1180 if (base == null) {
1181 log.error(tree.expr.pos(),
1182 "foreach.not.applicable.to.type",
1183 exprType,
1184 diags.fragment("type.req.array.or.iterable"));
1185 elemtype = types.createErrorType(exprType);
1186 } else {
1187 List<Type> iterableParams = base.allparams();
1188 elemtype = iterableParams.isEmpty()
1189 ? syms.objectType
1190 : types.upperBound(iterableParams.head);
1191 }
1192 }
1193 chk.checkType(tree.expr.pos(), elemtype, tree.var.sym.type);
1194 loopEnv.tree = tree; // before, we were not in loop!
1195 attribStat(tree.body, loopEnv);
1196 result = null;
1197 }
1198 finally {
1199 loopEnv.info.scope.leave();
1200 }
1201 }
1203 public void visitLabelled(JCLabeledStatement tree) {
1204 // Check that label is not used in an enclosing statement
1205 Env<AttrContext> env1 = env;
1206 while (env1 != null && !env1.tree.hasTag(CLASSDEF)) {
1207 if (env1.tree.hasTag(LABELLED) &&
1208 ((JCLabeledStatement) env1.tree).label == tree.label) {
1209 log.error(tree.pos(), "label.already.in.use",
1210 tree.label);
1211 break;
1212 }
1213 env1 = env1.next;
1214 }
1216 attribStat(tree.body, env.dup(tree));
1217 result = null;
1218 }
1220 public void visitSwitch(JCSwitch tree) {
1221 Type seltype = attribExpr(tree.selector, env);
1223 Env<AttrContext> switchEnv =
1224 env.dup(tree, env.info.dup(env.info.scope.dup()));
1226 try {
1228 boolean enumSwitch =
1229 allowEnums &&
1230 (seltype.tsym.flags() & Flags.ENUM) != 0;
1231 boolean stringSwitch = false;
1232 if (types.isSameType(seltype, syms.stringType)) {
1233 if (allowStringsInSwitch) {
1234 stringSwitch = true;
1235 } else {
1236 log.error(tree.selector.pos(), "string.switch.not.supported.in.source", sourceName);
1237 }
1238 }
1239 if (!enumSwitch && !stringSwitch)
1240 seltype = chk.checkType(tree.selector.pos(), seltype, syms.intType);
1242 // Attribute all cases and
1243 // check that there are no duplicate case labels or default clauses.
1244 Set<Object> labels = new HashSet<Object>(); // The set of case labels.
1245 boolean hasDefault = false; // Is there a default label?
1246 for (List<JCCase> l = tree.cases; l.nonEmpty(); l = l.tail) {
1247 JCCase c = l.head;
1248 Env<AttrContext> caseEnv =
1249 switchEnv.dup(c, env.info.dup(switchEnv.info.scope.dup()));
1250 try {
1251 if (c.pat != null) {
1252 if (enumSwitch) {
1253 Symbol sym = enumConstant(c.pat, seltype);
1254 if (sym == null) {
1255 log.error(c.pat.pos(), "enum.label.must.be.unqualified.enum");
1256 } else if (!labels.add(sym)) {
1257 log.error(c.pos(), "duplicate.case.label");
1258 }
1259 } else {
1260 Type pattype = attribExpr(c.pat, switchEnv, seltype);
1261 if (!pattype.hasTag(ERROR)) {
1262 if (pattype.constValue() == null) {
1263 log.error(c.pat.pos(),
1264 (stringSwitch ? "string.const.req" : "const.expr.req"));
1265 } else if (labels.contains(pattype.constValue())) {
1266 log.error(c.pos(), "duplicate.case.label");
1267 } else {
1268 labels.add(pattype.constValue());
1269 }
1270 }
1271 }
1272 } else if (hasDefault) {
1273 log.error(c.pos(), "duplicate.default.label");
1274 } else {
1275 hasDefault = true;
1276 }
1277 attribStats(c.stats, caseEnv);
1278 } finally {
1279 caseEnv.info.scope.leave();
1280 addVars(c.stats, switchEnv.info.scope);
1281 }
1282 }
1284 result = null;
1285 }
1286 finally {
1287 switchEnv.info.scope.leave();
1288 }
1289 }
1290 // where
1291 /** Add any variables defined in stats to the switch scope. */
1292 private static void addVars(List<JCStatement> stats, Scope switchScope) {
1293 for (;stats.nonEmpty(); stats = stats.tail) {
1294 JCTree stat = stats.head;
1295 if (stat.hasTag(VARDEF))
1296 switchScope.enter(((JCVariableDecl) stat).sym);
1297 }
1298 }
1299 // where
1300 /** Return the selected enumeration constant symbol, or null. */
1301 private Symbol enumConstant(JCTree tree, Type enumType) {
1302 if (!tree.hasTag(IDENT)) {
1303 log.error(tree.pos(), "enum.label.must.be.unqualified.enum");
1304 return syms.errSymbol;
1305 }
1306 JCIdent ident = (JCIdent)tree;
1307 Name name = ident.name;
1308 for (Scope.Entry e = enumType.tsym.members().lookup(name);
1309 e.scope != null; e = e.next()) {
1310 if (e.sym.kind == VAR) {
1311 Symbol s = ident.sym = e.sym;
1312 ((VarSymbol)s).getConstValue(); // ensure initializer is evaluated
1313 ident.type = s.type;
1314 return ((s.flags_field & Flags.ENUM) == 0)
1315 ? null : s;
1316 }
1317 }
1318 return null;
1319 }
1321 public void visitSynchronized(JCSynchronized tree) {
1322 chk.checkRefType(tree.pos(), attribExpr(tree.lock, env));
1323 attribStat(tree.body, env);
1324 result = null;
1325 }
1327 public void visitTry(JCTry tree) {
1328 // Create a new local environment with a local
1329 Env<AttrContext> localEnv = env.dup(tree, env.info.dup(env.info.scope.dup()));
1330 try {
1331 boolean isTryWithResource = tree.resources.nonEmpty();
1332 // Create a nested environment for attributing the try block if needed
1333 Env<AttrContext> tryEnv = isTryWithResource ?
1334 env.dup(tree, localEnv.info.dup(localEnv.info.scope.dup())) :
1335 localEnv;
1336 try {
1337 // Attribute resource declarations
1338 for (JCTree resource : tree.resources) {
1339 CheckContext twrContext = new Check.NestedCheckContext(resultInfo.checkContext) {
1340 @Override
1341 public void report(DiagnosticPosition pos, JCDiagnostic details) {
1342 chk.basicHandler.report(pos, diags.fragment("try.not.applicable.to.type", details));
1343 }
1344 };
1345 ResultInfo twrResult = new ResultInfo(VAL, syms.autoCloseableType, twrContext);
1346 if (resource.hasTag(VARDEF)) {
1347 attribStat(resource, tryEnv);
1348 twrResult.check(resource, resource.type);
1350 //check that resource type cannot throw InterruptedException
1351 checkAutoCloseable(resource.pos(), localEnv, resource.type);
1353 VarSymbol var = ((JCVariableDecl) resource).sym;
1354 var.setData(ElementKind.RESOURCE_VARIABLE);
1355 } else {
1356 attribTree(resource, tryEnv, twrResult);
1357 }
1358 }
1359 // Attribute body
1360 attribStat(tree.body, tryEnv);
1361 } finally {
1362 if (isTryWithResource)
1363 tryEnv.info.scope.leave();
1364 }
1366 // Attribute catch clauses
1367 for (List<JCCatch> l = tree.catchers; l.nonEmpty(); l = l.tail) {
1368 JCCatch c = l.head;
1369 Env<AttrContext> catchEnv =
1370 localEnv.dup(c, localEnv.info.dup(localEnv.info.scope.dup()));
1371 try {
1372 Type ctype = attribStat(c.param, catchEnv);
1373 if (TreeInfo.isMultiCatch(c)) {
1374 //multi-catch parameter is implicitly marked as final
1375 c.param.sym.flags_field |= FINAL | UNION;
1376 }
1377 if (c.param.sym.kind == Kinds.VAR) {
1378 c.param.sym.setData(ElementKind.EXCEPTION_PARAMETER);
1379 }
1380 chk.checkType(c.param.vartype.pos(),
1381 chk.checkClassType(c.param.vartype.pos(), ctype),
1382 syms.throwableType);
1383 attribStat(c.body, catchEnv);
1384 } finally {
1385 catchEnv.info.scope.leave();
1386 }
1387 }
1389 // Attribute finalizer
1390 if (tree.finalizer != null) attribStat(tree.finalizer, localEnv);
1391 result = null;
1392 }
1393 finally {
1394 localEnv.info.scope.leave();
1395 }
1396 }
1398 void checkAutoCloseable(DiagnosticPosition pos, Env<AttrContext> env, Type resource) {
1399 if (!resource.isErroneous() &&
1400 types.asSuper(resource, syms.autoCloseableType.tsym) != null &&
1401 !types.isSameType(resource, syms.autoCloseableType)) { // Don't emit warning for AutoCloseable itself
1402 Symbol close = syms.noSymbol;
1403 Log.DiagnosticHandler discardHandler = new Log.DiscardDiagnosticHandler(log);
1404 try {
1405 close = rs.resolveQualifiedMethod(pos,
1406 env,
1407 resource,
1408 names.close,
1409 List.<Type>nil(),
1410 List.<Type>nil());
1411 }
1412 finally {
1413 log.popDiagnosticHandler(discardHandler);
1414 }
1415 if (close.kind == MTH &&
1416 close.overrides(syms.autoCloseableClose, resource.tsym, types, true) &&
1417 chk.isHandled(syms.interruptedExceptionType, types.memberType(resource, close).getThrownTypes()) &&
1418 env.info.lint.isEnabled(LintCategory.TRY)) {
1419 log.warning(LintCategory.TRY, pos, "try.resource.throws.interrupted.exc", resource);
1420 }
1421 }
1422 }
1424 public void visitConditional(JCConditional tree) {
1425 Type condtype = attribExpr(tree.cond, env, syms.booleanType);
1427 tree.polyKind = (!allowPoly ||
1428 pt().hasTag(NONE) && pt() != Type.recoveryType ||
1429 isBooleanOrNumeric(env, tree)) ?
1430 PolyKind.STANDALONE : PolyKind.POLY;
1432 if (tree.polyKind == PolyKind.POLY && resultInfo.pt.hasTag(VOID)) {
1433 //cannot get here (i.e. it means we are returning from void method - which is already an error)
1434 resultInfo.checkContext.report(tree, diags.fragment("conditional.target.cant.be.void"));
1435 result = tree.type = types.createErrorType(resultInfo.pt);
1436 return;
1437 }
1439 ResultInfo condInfo = tree.polyKind == PolyKind.STANDALONE ?
1440 unknownExprInfo :
1441 resultInfo.dup(new Check.NestedCheckContext(resultInfo.checkContext) {
1442 //this will use enclosing check context to check compatibility of
1443 //subexpression against target type; if we are in a method check context,
1444 //depending on whether boxing is allowed, we could have incompatibilities
1445 @Override
1446 public void report(DiagnosticPosition pos, JCDiagnostic details) {
1447 enclosingContext.report(pos, diags.fragment("incompatible.type.in.conditional", details));
1448 }
1449 });
1451 Type truetype = attribTree(tree.truepart, env, condInfo);
1452 Type falsetype = attribTree(tree.falsepart, env, condInfo);
1454 Type owntype = (tree.polyKind == PolyKind.STANDALONE) ? condType(tree, truetype, falsetype) : pt();
1455 if (condtype.constValue() != null &&
1456 truetype.constValue() != null &&
1457 falsetype.constValue() != null &&
1458 !owntype.hasTag(NONE)) {
1459 //constant folding
1460 owntype = cfolder.coerce(condtype.isTrue() ? truetype : falsetype, owntype);
1461 }
1462 result = check(tree, owntype, VAL, resultInfo);
1463 }
1464 //where
1465 private boolean isBooleanOrNumeric(Env<AttrContext> env, JCExpression tree) {
1466 switch (tree.getTag()) {
1467 case LITERAL: return ((JCLiteral)tree).typetag.isSubRangeOf(DOUBLE) ||
1468 ((JCLiteral)tree).typetag == BOOLEAN ||
1469 ((JCLiteral)tree).typetag == BOT;
1470 case LAMBDA: case REFERENCE: return false;
1471 case PARENS: return isBooleanOrNumeric(env, ((JCParens)tree).expr);
1472 case CONDEXPR:
1473 JCConditional condTree = (JCConditional)tree;
1474 return isBooleanOrNumeric(env, condTree.truepart) &&
1475 isBooleanOrNumeric(env, condTree.falsepart);
1476 case APPLY:
1477 JCMethodInvocation speculativeMethodTree =
1478 (JCMethodInvocation)deferredAttr.attribSpeculative(tree, env, unknownExprInfo);
1479 Type owntype = TreeInfo.symbol(speculativeMethodTree.meth).type.getReturnType();
1480 return types.unboxedTypeOrType(owntype).isPrimitive();
1481 case NEWCLASS:
1482 JCExpression className =
1483 removeClassParams.translate(((JCNewClass)tree).clazz);
1484 JCExpression speculativeNewClassTree =
1485 (JCExpression)deferredAttr.attribSpeculative(className, env, unknownTypeInfo);
1486 return types.unboxedTypeOrType(speculativeNewClassTree.type).isPrimitive();
1487 default:
1488 Type speculativeType = deferredAttr.attribSpeculative(tree, env, unknownExprInfo).type;
1489 speculativeType = types.unboxedTypeOrType(speculativeType);
1490 return speculativeType.isPrimitive();
1491 }
1492 }
1493 //where
1494 TreeTranslator removeClassParams = new TreeTranslator() {
1495 @Override
1496 public void visitTypeApply(JCTypeApply tree) {
1497 result = translate(tree.clazz);
1498 }
1499 };
1501 /** Compute the type of a conditional expression, after
1502 * checking that it exists. See JLS 15.25. Does not take into
1503 * account the special case where condition and both arms
1504 * are constants.
1505 *
1506 * @param pos The source position to be used for error
1507 * diagnostics.
1508 * @param thentype The type of the expression's then-part.
1509 * @param elsetype The type of the expression's else-part.
1510 */
1511 private Type condType(DiagnosticPosition pos,
1512 Type thentype, Type elsetype) {
1513 // If same type, that is the result
1514 if (types.isSameType(thentype, elsetype))
1515 return thentype.baseType();
1517 Type thenUnboxed = (!allowBoxing || thentype.isPrimitive())
1518 ? thentype : types.unboxedType(thentype);
1519 Type elseUnboxed = (!allowBoxing || elsetype.isPrimitive())
1520 ? elsetype : types.unboxedType(elsetype);
1522 // Otherwise, if both arms can be converted to a numeric
1523 // type, return the least numeric type that fits both arms
1524 // (i.e. return larger of the two, or return int if one
1525 // arm is short, the other is char).
1526 if (thenUnboxed.isPrimitive() && elseUnboxed.isPrimitive()) {
1527 // If one arm has an integer subrange type (i.e., byte,
1528 // short, or char), and the other is an integer constant
1529 // that fits into the subrange, return the subrange type.
1530 if (thenUnboxed.getTag().isStrictSubRangeOf(INT) &&
1531 elseUnboxed.hasTag(INT) &&
1532 types.isAssignable(elseUnboxed, thenUnboxed)) {
1533 return thenUnboxed.baseType();
1534 }
1535 if (elseUnboxed.getTag().isStrictSubRangeOf(INT) &&
1536 thenUnboxed.hasTag(INT) &&
1537 types.isAssignable(thenUnboxed, elseUnboxed)) {
1538 return elseUnboxed.baseType();
1539 }
1541 for (TypeTag tag : primitiveTags) {
1542 Type candidate = syms.typeOfTag[tag.ordinal()];
1543 if (types.isSubtype(thenUnboxed, candidate) &&
1544 types.isSubtype(elseUnboxed, candidate)) {
1545 return candidate;
1546 }
1547 }
1548 }
1550 // Those were all the cases that could result in a primitive
1551 if (allowBoxing) {
1552 if (thentype.isPrimitive())
1553 thentype = types.boxedClass(thentype).type;
1554 if (elsetype.isPrimitive())
1555 elsetype = types.boxedClass(elsetype).type;
1556 }
1558 if (types.isSubtype(thentype, elsetype))
1559 return elsetype.baseType();
1560 if (types.isSubtype(elsetype, thentype))
1561 return thentype.baseType();
1563 if (!allowBoxing || thentype.hasTag(VOID) || elsetype.hasTag(VOID)) {
1564 log.error(pos, "neither.conditional.subtype",
1565 thentype, elsetype);
1566 return thentype.baseType();
1567 }
1569 // both are known to be reference types. The result is
1570 // lub(thentype,elsetype). This cannot fail, as it will
1571 // always be possible to infer "Object" if nothing better.
1572 return types.lub(thentype.baseType(), elsetype.baseType());
1573 }
1575 final static TypeTag[] primitiveTags = new TypeTag[]{
1576 BYTE,
1577 CHAR,
1578 SHORT,
1579 INT,
1580 LONG,
1581 FLOAT,
1582 DOUBLE,
1583 BOOLEAN,
1584 };
1586 public void visitIf(JCIf tree) {
1587 attribExpr(tree.cond, env, syms.booleanType);
1588 attribStat(tree.thenpart, env);
1589 if (tree.elsepart != null)
1590 attribStat(tree.elsepart, env);
1591 chk.checkEmptyIf(tree);
1592 result = null;
1593 }
1595 public void visitExec(JCExpressionStatement tree) {
1596 //a fresh environment is required for 292 inference to work properly ---
1597 //see Infer.instantiatePolymorphicSignatureInstance()
1598 Env<AttrContext> localEnv = env.dup(tree);
1599 attribExpr(tree.expr, localEnv);
1600 result = null;
1601 }
1603 public void visitBreak(JCBreak tree) {
1604 tree.target = findJumpTarget(tree.pos(), tree.getTag(), tree.label, env);
1605 result = null;
1606 }
1608 public void visitContinue(JCContinue tree) {
1609 tree.target = findJumpTarget(tree.pos(), tree.getTag(), tree.label, env);
1610 result = null;
1611 }
1612 //where
1613 /** Return the target of a break or continue statement, if it exists,
1614 * report an error if not.
1615 * Note: The target of a labelled break or continue is the
1616 * (non-labelled) statement tree referred to by the label,
1617 * not the tree representing the labelled statement itself.
1618 *
1619 * @param pos The position to be used for error diagnostics
1620 * @param tag The tag of the jump statement. This is either
1621 * Tree.BREAK or Tree.CONTINUE.
1622 * @param label The label of the jump statement, or null if no
1623 * label is given.
1624 * @param env The environment current at the jump statement.
1625 */
1626 private JCTree findJumpTarget(DiagnosticPosition pos,
1627 JCTree.Tag tag,
1628 Name label,
1629 Env<AttrContext> env) {
1630 // Search environments outwards from the point of jump.
1631 Env<AttrContext> env1 = env;
1632 LOOP:
1633 while (env1 != null) {
1634 switch (env1.tree.getTag()) {
1635 case LABELLED:
1636 JCLabeledStatement labelled = (JCLabeledStatement)env1.tree;
1637 if (label == labelled.label) {
1638 // If jump is a continue, check that target is a loop.
1639 if (tag == CONTINUE) {
1640 if (!labelled.body.hasTag(DOLOOP) &&
1641 !labelled.body.hasTag(WHILELOOP) &&
1642 !labelled.body.hasTag(FORLOOP) &&
1643 !labelled.body.hasTag(FOREACHLOOP))
1644 log.error(pos, "not.loop.label", label);
1645 // Found labelled statement target, now go inwards
1646 // to next non-labelled tree.
1647 return TreeInfo.referencedStatement(labelled);
1648 } else {
1649 return labelled;
1650 }
1651 }
1652 break;
1653 case DOLOOP:
1654 case WHILELOOP:
1655 case FORLOOP:
1656 case FOREACHLOOP:
1657 if (label == null) return env1.tree;
1658 break;
1659 case SWITCH:
1660 if (label == null && tag == BREAK) return env1.tree;
1661 break;
1662 case LAMBDA:
1663 case METHODDEF:
1664 case CLASSDEF:
1665 break LOOP;
1666 default:
1667 }
1668 env1 = env1.next;
1669 }
1670 if (label != null)
1671 log.error(pos, "undef.label", label);
1672 else if (tag == CONTINUE)
1673 log.error(pos, "cont.outside.loop");
1674 else
1675 log.error(pos, "break.outside.switch.loop");
1676 return null;
1677 }
1679 public void visitReturn(JCReturn tree) {
1680 // Check that there is an enclosing method which is
1681 // nested within than the enclosing class.
1682 if (env.info.returnResult == null) {
1683 log.error(tree.pos(), "ret.outside.meth");
1684 } else {
1685 // Attribute return expression, if it exists, and check that
1686 // it conforms to result type of enclosing method.
1687 if (tree.expr != null) {
1688 if (env.info.returnResult.pt.hasTag(VOID)) {
1689 env.info.returnResult.checkContext.report(tree.expr.pos(),
1690 diags.fragment("unexpected.ret.val"));
1691 }
1692 attribTree(tree.expr, env, env.info.returnResult);
1693 } else if (!env.info.returnResult.pt.hasTag(VOID) &&
1694 !env.info.returnResult.pt.hasTag(NONE)) {
1695 env.info.returnResult.checkContext.report(tree.pos(),
1696 diags.fragment("missing.ret.val"));
1697 }
1698 }
1699 result = null;
1700 }
1702 public void visitThrow(JCThrow tree) {
1703 Type owntype = attribExpr(tree.expr, env, allowPoly ? Type.noType : syms.throwableType);
1704 if (allowPoly) {
1705 chk.checkType(tree, owntype, syms.throwableType);
1706 }
1707 result = null;
1708 }
1710 public void visitAssert(JCAssert tree) {
1711 attribExpr(tree.cond, env, syms.booleanType);
1712 if (tree.detail != null) {
1713 chk.checkNonVoid(tree.detail.pos(), attribExpr(tree.detail, env));
1714 }
1715 result = null;
1716 }
1718 /** Visitor method for method invocations.
1719 * NOTE: The method part of an application will have in its type field
1720 * the return type of the method, not the method's type itself!
1721 */
1722 public void visitApply(JCMethodInvocation tree) {
1723 // The local environment of a method application is
1724 // a new environment nested in the current one.
1725 Env<AttrContext> localEnv = env.dup(tree, env.info.dup());
1727 // The types of the actual method arguments.
1728 List<Type> argtypes;
1730 // The types of the actual method type arguments.
1731 List<Type> typeargtypes = null;
1733 Name methName = TreeInfo.name(tree.meth);
1735 boolean isConstructorCall =
1736 methName == names._this || methName == names._super;
1738 ListBuffer<Type> argtypesBuf = ListBuffer.lb();
1739 if (isConstructorCall) {
1740 // We are seeing a ...this(...) or ...super(...) call.
1741 // Check that this is the first statement in a constructor.
1742 if (checkFirstConstructorStat(tree, env)) {
1744 // Record the fact
1745 // that this is a constructor call (using isSelfCall).
1746 localEnv.info.isSelfCall = true;
1748 // Attribute arguments, yielding list of argument types.
1749 attribArgs(tree.args, localEnv, argtypesBuf);
1750 argtypes = argtypesBuf.toList();
1751 typeargtypes = attribTypes(tree.typeargs, localEnv);
1753 // Variable `site' points to the class in which the called
1754 // constructor is defined.
1755 Type site = env.enclClass.sym.type;
1756 if (methName == names._super) {
1757 if (site == syms.objectType) {
1758 log.error(tree.meth.pos(), "no.superclass", site);
1759 site = types.createErrorType(syms.objectType);
1760 } else {
1761 site = types.supertype(site);
1762 }
1763 }
1765 if (site.hasTag(CLASS)) {
1766 Type encl = site.getEnclosingType();
1767 while (encl != null && encl.hasTag(TYPEVAR))
1768 encl = encl.getUpperBound();
1769 if (encl.hasTag(CLASS)) {
1770 // we are calling a nested class
1772 if (tree.meth.hasTag(SELECT)) {
1773 JCTree qualifier = ((JCFieldAccess) tree.meth).selected;
1775 // We are seeing a prefixed call, of the form
1776 // <expr>.super(...).
1777 // Check that the prefix expression conforms
1778 // to the outer instance type of the class.
1779 chk.checkRefType(qualifier.pos(),
1780 attribExpr(qualifier, localEnv,
1781 encl));
1782 } else if (methName == names._super) {
1783 // qualifier omitted; check for existence
1784 // of an appropriate implicit qualifier.
1785 rs.resolveImplicitThis(tree.meth.pos(),
1786 localEnv, site, true);
1787 }
1788 } else if (tree.meth.hasTag(SELECT)) {
1789 log.error(tree.meth.pos(), "illegal.qual.not.icls",
1790 site.tsym);
1791 }
1793 // if we're calling a java.lang.Enum constructor,
1794 // prefix the implicit String and int parameters
1795 if (site.tsym == syms.enumSym && allowEnums)
1796 argtypes = argtypes.prepend(syms.intType).prepend(syms.stringType);
1798 // Resolve the called constructor under the assumption
1799 // that we are referring to a superclass instance of the
1800 // current instance (JLS ???).
1801 boolean selectSuperPrev = localEnv.info.selectSuper;
1802 localEnv.info.selectSuper = true;
1803 localEnv.info.pendingResolutionPhase = null;
1804 Symbol sym = rs.resolveConstructor(
1805 tree.meth.pos(), localEnv, site, argtypes, typeargtypes);
1806 localEnv.info.selectSuper = selectSuperPrev;
1808 // Set method symbol to resolved constructor...
1809 TreeInfo.setSymbol(tree.meth, sym);
1811 // ...and check that it is legal in the current context.
1812 // (this will also set the tree's type)
1813 Type mpt = newMethodTemplate(resultInfo.pt, argtypes, typeargtypes);
1814 checkId(tree.meth, site, sym, localEnv, new ResultInfo(MTH, mpt));
1815 }
1816 // Otherwise, `site' is an error type and we do nothing
1817 }
1818 result = tree.type = syms.voidType;
1819 } else {
1820 // Otherwise, we are seeing a regular method call.
1821 // Attribute the arguments, yielding list of argument types, ...
1822 int kind = attribArgs(tree.args, localEnv, argtypesBuf);
1823 argtypes = argtypesBuf.toList();
1824 typeargtypes = attribAnyTypes(tree.typeargs, localEnv);
1826 // ... and attribute the method using as a prototype a methodtype
1827 // whose formal argument types is exactly the list of actual
1828 // arguments (this will also set the method symbol).
1829 Type mpt = newMethodTemplate(resultInfo.pt, argtypes, typeargtypes);
1830 localEnv.info.pendingResolutionPhase = null;
1831 Type mtype = attribTree(tree.meth, localEnv, new ResultInfo(kind, mpt, resultInfo.checkContext));
1833 // Compute the result type.
1834 Type restype = mtype.getReturnType();
1835 if (restype.hasTag(WILDCARD))
1836 throw new AssertionError(mtype);
1838 Type qualifier = (tree.meth.hasTag(SELECT))
1839 ? ((JCFieldAccess) tree.meth).selected.type
1840 : env.enclClass.sym.type;
1841 restype = adjustMethodReturnType(qualifier, methName, argtypes, restype);
1843 chk.checkRefTypes(tree.typeargs, typeargtypes);
1845 // Check that value of resulting type is admissible in the
1846 // current context. Also, capture the return type
1847 result = check(tree, capture(restype), VAL, resultInfo);
1848 }
1849 chk.validate(tree.typeargs, localEnv);
1850 }
1851 //where
1852 Type adjustMethodReturnType(Type qualifierType, Name methodName, List<Type> argtypes, Type restype) {
1853 if (allowCovariantReturns &&
1854 methodName == names.clone &&
1855 types.isArray(qualifierType)) {
1856 // as a special case, array.clone() has a result that is
1857 // the same as static type of the array being cloned
1858 return qualifierType;
1859 } else if (allowGenerics &&
1860 methodName == names.getClass &&
1861 argtypes.isEmpty()) {
1862 // as a special case, x.getClass() has type Class<? extends |X|>
1863 return new ClassType(restype.getEnclosingType(),
1864 List.<Type>of(new WildcardType(types.erasure(qualifierType),
1865 BoundKind.EXTENDS,
1866 syms.boundClass)),
1867 restype.tsym);
1868 } else {
1869 return restype;
1870 }
1871 }
1873 /** Check that given application node appears as first statement
1874 * in a constructor call.
1875 * @param tree The application node
1876 * @param env The environment current at the application.
1877 */
1878 boolean checkFirstConstructorStat(JCMethodInvocation tree, Env<AttrContext> env) {
1879 JCMethodDecl enclMethod = env.enclMethod;
1880 if (enclMethod != null && enclMethod.name == names.init) {
1881 JCBlock body = enclMethod.body;
1882 if (body.stats.head.hasTag(EXEC) &&
1883 ((JCExpressionStatement) body.stats.head).expr == tree)
1884 return true;
1885 }
1886 log.error(tree.pos(),"call.must.be.first.stmt.in.ctor",
1887 TreeInfo.name(tree.meth));
1888 return false;
1889 }
1891 /** Obtain a method type with given argument types.
1892 */
1893 Type newMethodTemplate(Type restype, List<Type> argtypes, List<Type> typeargtypes) {
1894 MethodType mt = new MethodType(argtypes, restype, List.<Type>nil(), syms.methodClass);
1895 return (typeargtypes == null) ? mt : (Type)new ForAll(typeargtypes, mt);
1896 }
1898 public void visitNewClass(final JCNewClass tree) {
1899 Type owntype = types.createErrorType(tree.type);
1901 // The local environment of a class creation is
1902 // a new environment nested in the current one.
1903 Env<AttrContext> localEnv = env.dup(tree, env.info.dup());
1905 // The anonymous inner class definition of the new expression,
1906 // if one is defined by it.
1907 JCClassDecl cdef = tree.def;
1909 // If enclosing class is given, attribute it, and
1910 // complete class name to be fully qualified
1911 JCExpression clazz = tree.clazz; // Class field following new
1912 JCExpression clazzid; // Identifier in class field
1913 JCAnnotatedType annoclazzid; // Annotated type enclosing clazzid
1914 annoclazzid = null;
1916 if (clazz.hasTag(TYPEAPPLY)) {
1917 clazzid = ((JCTypeApply) clazz).clazz;
1918 if (clazzid.hasTag(ANNOTATED_TYPE)) {
1919 annoclazzid = (JCAnnotatedType) clazzid;
1920 clazzid = annoclazzid.underlyingType;
1921 }
1922 } else {
1923 if (clazz.hasTag(ANNOTATED_TYPE)) {
1924 annoclazzid = (JCAnnotatedType) clazz;
1925 clazzid = annoclazzid.underlyingType;
1926 } else {
1927 clazzid = clazz;
1928 }
1929 }
1931 JCExpression clazzid1 = clazzid; // The same in fully qualified form
1933 if (tree.encl != null) {
1934 // We are seeing a qualified new, of the form
1935 // <expr>.new C <...> (...) ...
1936 // In this case, we let clazz stand for the name of the
1937 // allocated class C prefixed with the type of the qualifier
1938 // expression, so that we can
1939 // resolve it with standard techniques later. I.e., if
1940 // <expr> has type T, then <expr>.new C <...> (...)
1941 // yields a clazz T.C.
1942 Type encltype = chk.checkRefType(tree.encl.pos(),
1943 attribExpr(tree.encl, env));
1944 // TODO 308: in <expr>.new C, do we also want to add the type annotations
1945 // from expr to the combined type, or not? Yes, do this.
1946 clazzid1 = make.at(clazz.pos).Select(make.Type(encltype),
1947 ((JCIdent) clazzid).name);
1949 EndPosTable endPosTable = this.env.toplevel.endPositions;
1950 endPosTable.storeEnd(clazzid1, tree.getEndPosition(endPosTable));
1951 if (clazz.hasTag(ANNOTATED_TYPE)) {
1952 JCAnnotatedType annoType = (JCAnnotatedType) clazz;
1953 List<JCAnnotation> annos = annoType.annotations;
1955 if (annoType.underlyingType.hasTag(TYPEAPPLY)) {
1956 clazzid1 = make.at(tree.pos).
1957 TypeApply(clazzid1,
1958 ((JCTypeApply) clazz).arguments);
1959 }
1961 clazzid1 = make.at(tree.pos).
1962 AnnotatedType(annos, clazzid1);
1963 } else if (clazz.hasTag(TYPEAPPLY)) {
1964 clazzid1 = make.at(tree.pos).
1965 TypeApply(clazzid1,
1966 ((JCTypeApply) clazz).arguments);
1967 }
1969 clazz = clazzid1;
1970 }
1972 // Attribute clazz expression and store
1973 // symbol + type back into the attributed tree.
1974 Type clazztype = TreeInfo.isEnumInit(env.tree) ?
1975 attribIdentAsEnumType(env, (JCIdent)clazz) :
1976 attribType(clazz, env);
1978 clazztype = chk.checkDiamond(tree, clazztype);
1979 chk.validate(clazz, localEnv);
1980 if (tree.encl != null) {
1981 // We have to work in this case to store
1982 // symbol + type back into the attributed tree.
1983 tree.clazz.type = clazztype;
1984 TreeInfo.setSymbol(clazzid, TreeInfo.symbol(clazzid1));
1985 clazzid.type = ((JCIdent) clazzid).sym.type;
1986 if (annoclazzid != null) {
1987 annoclazzid.type = clazzid.type;
1988 }
1989 if (!clazztype.isErroneous()) {
1990 if (cdef != null && clazztype.tsym.isInterface()) {
1991 log.error(tree.encl.pos(), "anon.class.impl.intf.no.qual.for.new");
1992 } else if (clazztype.tsym.isStatic()) {
1993 log.error(tree.encl.pos(), "qualified.new.of.static.class", clazztype.tsym);
1994 }
1995 }
1996 } else if (!clazztype.tsym.isInterface() &&
1997 clazztype.getEnclosingType().hasTag(CLASS)) {
1998 // Check for the existence of an apropos outer instance
1999 rs.resolveImplicitThis(tree.pos(), env, clazztype);
2000 }
2002 // Attribute constructor arguments.
2003 ListBuffer<Type> argtypesBuf = ListBuffer.lb();
2004 int pkind = attribArgs(tree.args, localEnv, argtypesBuf);
2005 List<Type> argtypes = argtypesBuf.toList();
2006 List<Type> typeargtypes = attribTypes(tree.typeargs, localEnv);
2008 // If we have made no mistakes in the class type...
2009 if (clazztype.hasTag(CLASS)) {
2010 // Enums may not be instantiated except implicitly
2011 if (allowEnums &&
2012 (clazztype.tsym.flags_field&Flags.ENUM) != 0 &&
2013 (!env.tree.hasTag(VARDEF) ||
2014 (((JCVariableDecl) env.tree).mods.flags&Flags.ENUM) == 0 ||
2015 ((JCVariableDecl) env.tree).init != tree))
2016 log.error(tree.pos(), "enum.cant.be.instantiated");
2017 // Check that class is not abstract
2018 if (cdef == null &&
2019 (clazztype.tsym.flags() & (ABSTRACT | INTERFACE)) != 0) {
2020 log.error(tree.pos(), "abstract.cant.be.instantiated",
2021 clazztype.tsym);
2022 } else if (cdef != null && clazztype.tsym.isInterface()) {
2023 // Check that no constructor arguments are given to
2024 // anonymous classes implementing an interface
2025 if (!argtypes.isEmpty())
2026 log.error(tree.args.head.pos(), "anon.class.impl.intf.no.args");
2028 if (!typeargtypes.isEmpty())
2029 log.error(tree.typeargs.head.pos(), "anon.class.impl.intf.no.typeargs");
2031 // Error recovery: pretend no arguments were supplied.
2032 argtypes = List.nil();
2033 typeargtypes = List.nil();
2034 } else if (TreeInfo.isDiamond(tree)) {
2035 ClassType site = new ClassType(clazztype.getEnclosingType(),
2036 clazztype.tsym.type.getTypeArguments(),
2037 clazztype.tsym);
2039 Env<AttrContext> diamondEnv = localEnv.dup(tree);
2040 diamondEnv.info.selectSuper = cdef != null;
2041 diamondEnv.info.pendingResolutionPhase = null;
2043 //if the type of the instance creation expression is a class type
2044 //apply method resolution inference (JLS 15.12.2.7). The return type
2045 //of the resolved constructor will be a partially instantiated type
2046 Symbol constructor = rs.resolveDiamond(tree.pos(),
2047 diamondEnv,
2048 site,
2049 argtypes,
2050 typeargtypes);
2051 tree.constructor = constructor.baseSymbol();
2053 final TypeSymbol csym = clazztype.tsym;
2054 ResultInfo diamondResult = new ResultInfo(MTH, newMethodTemplate(resultInfo.pt, argtypes, typeargtypes), new Check.NestedCheckContext(resultInfo.checkContext) {
2055 @Override
2056 public void report(DiagnosticPosition _unused, JCDiagnostic details) {
2057 enclosingContext.report(tree.clazz,
2058 diags.fragment("cant.apply.diamond.1", diags.fragment("diamond", csym), details));
2059 }
2060 });
2061 Type constructorType = tree.constructorType = types.createErrorType(clazztype);
2062 constructorType = checkId(tree, site,
2063 constructor,
2064 diamondEnv,
2065 diamondResult);
2067 tree.clazz.type = types.createErrorType(clazztype);
2068 if (!constructorType.isErroneous()) {
2069 tree.clazz.type = clazztype = constructorType.getReturnType();
2070 tree.constructorType = types.createMethodTypeWithReturn(constructorType, syms.voidType);
2071 }
2072 clazztype = chk.checkClassType(tree.clazz, tree.clazz.type, true);
2073 }
2075 // Resolve the called constructor under the assumption
2076 // that we are referring to a superclass instance of the
2077 // current instance (JLS ???).
2078 else {
2079 //the following code alters some of the fields in the current
2080 //AttrContext - hence, the current context must be dup'ed in
2081 //order to avoid downstream failures
2082 Env<AttrContext> rsEnv = localEnv.dup(tree);
2083 rsEnv.info.selectSuper = cdef != null;
2084 rsEnv.info.pendingResolutionPhase = null;
2085 tree.constructor = rs.resolveConstructor(
2086 tree.pos(), rsEnv, clazztype, argtypes, typeargtypes);
2087 if (cdef == null) { //do not check twice!
2088 tree.constructorType = checkId(tree,
2089 clazztype,
2090 tree.constructor,
2091 rsEnv,
2092 new ResultInfo(pkind, newMethodTemplate(syms.voidType, argtypes, typeargtypes)));
2093 if (rsEnv.info.lastResolveVarargs())
2094 Assert.check(tree.constructorType.isErroneous() || tree.varargsElement != null);
2095 }
2096 if (cdef == null &&
2097 !clazztype.isErroneous() &&
2098 clazztype.getTypeArguments().nonEmpty() &&
2099 findDiamonds) {
2100 findDiamond(localEnv, tree, clazztype);
2101 }
2102 }
2104 if (cdef != null) {
2105 // We are seeing an anonymous class instance creation.
2106 // In this case, the class instance creation
2107 // expression
2108 //
2109 // E.new <typeargs1>C<typargs2>(args) { ... }
2110 //
2111 // is represented internally as
2112 //
2113 // E . new <typeargs1>C<typargs2>(args) ( class <empty-name> { ... } ) .
2114 //
2115 // This expression is then *transformed* as follows:
2116 //
2117 // (1) add a STATIC flag to the class definition
2118 // if the current environment is static
2119 // (2) add an extends or implements clause
2120 // (3) add a constructor.
2121 //
2122 // For instance, if C is a class, and ET is the type of E,
2123 // the expression
2124 //
2125 // E.new <typeargs1>C<typargs2>(args) { ... }
2126 //
2127 // is translated to (where X is a fresh name and typarams is the
2128 // parameter list of the super constructor):
2129 //
2130 // new <typeargs1>X(<*nullchk*>E, args) where
2131 // X extends C<typargs2> {
2132 // <typarams> X(ET e, args) {
2133 // e.<typeargs1>super(args)
2134 // }
2135 // ...
2136 // }
2137 if (Resolve.isStatic(env)) cdef.mods.flags |= STATIC;
2139 if (clazztype.tsym.isInterface()) {
2140 cdef.implementing = List.of(clazz);
2141 } else {
2142 cdef.extending = clazz;
2143 }
2145 attribStat(cdef, localEnv);
2147 checkLambdaCandidate(tree, cdef.sym, clazztype);
2149 // If an outer instance is given,
2150 // prefix it to the constructor arguments
2151 // and delete it from the new expression
2152 if (tree.encl != null && !clazztype.tsym.isInterface()) {
2153 tree.args = tree.args.prepend(makeNullCheck(tree.encl));
2154 argtypes = argtypes.prepend(tree.encl.type);
2155 tree.encl = null;
2156 }
2158 // Reassign clazztype and recompute constructor.
2159 clazztype = cdef.sym.type;
2160 Symbol sym = tree.constructor = rs.resolveConstructor(
2161 tree.pos(), localEnv, clazztype, argtypes, typeargtypes);
2162 Assert.check(sym.kind < AMBIGUOUS);
2163 tree.constructor = sym;
2164 tree.constructorType = checkId(tree,
2165 clazztype,
2166 tree.constructor,
2167 localEnv,
2168 new ResultInfo(pkind, newMethodTemplate(syms.voidType, argtypes, typeargtypes)));
2169 } else {
2170 if (tree.clazz.hasTag(ANNOTATED_TYPE)) {
2171 checkForDeclarationAnnotations(((JCAnnotatedType) tree.clazz).annotations,
2172 tree.clazz.type.tsym);
2173 }
2174 }
2176 if (tree.constructor != null && tree.constructor.kind == MTH)
2177 owntype = clazztype;
2178 }
2179 result = check(tree, owntype, VAL, resultInfo);
2180 chk.validate(tree.typeargs, localEnv);
2181 }
2182 //where
2183 void findDiamond(Env<AttrContext> env, JCNewClass tree, Type clazztype) {
2184 JCTypeApply ta = (JCTypeApply)tree.clazz;
2185 List<JCExpression> prevTypeargs = ta.arguments;
2186 try {
2187 //create a 'fake' diamond AST node by removing type-argument trees
2188 ta.arguments = List.nil();
2189 ResultInfo findDiamondResult = new ResultInfo(VAL,
2190 resultInfo.checkContext.inferenceContext().free(resultInfo.pt) ? Type.noType : pt());
2191 Type inferred = deferredAttr.attribSpeculative(tree, env, findDiamondResult).type;
2192 Type polyPt = allowPoly ?
2193 syms.objectType :
2194 clazztype;
2195 if (!inferred.isErroneous() &&
2196 (allowPoly && pt() == Infer.anyPoly ?
2197 types.isSameType(inferred, clazztype) :
2198 types.isAssignable(inferred, pt().hasTag(NONE) ? polyPt : pt(), types.noWarnings))) {
2199 String key = types.isSameType(clazztype, inferred) ?
2200 "diamond.redundant.args" :
2201 "diamond.redundant.args.1";
2202 log.warning(tree.clazz.pos(), key, clazztype, inferred);
2203 }
2204 } finally {
2205 ta.arguments = prevTypeargs;
2206 }
2207 }
2209 private void checkLambdaCandidate(JCNewClass tree, ClassSymbol csym, Type clazztype) {
2210 if (allowLambda &&
2211 identifyLambdaCandidate &&
2212 clazztype.hasTag(CLASS) &&
2213 !pt().hasTag(NONE) &&
2214 types.isFunctionalInterface(clazztype.tsym)) {
2215 Symbol descriptor = types.findDescriptorSymbol(clazztype.tsym);
2216 int count = 0;
2217 boolean found = false;
2218 for (Symbol sym : csym.members().getElements()) {
2219 if ((sym.flags() & SYNTHETIC) != 0 ||
2220 sym.isConstructor()) continue;
2221 count++;
2222 if (sym.kind != MTH ||
2223 !sym.name.equals(descriptor.name)) continue;
2224 Type mtype = types.memberType(clazztype, sym);
2225 if (types.overrideEquivalent(mtype, types.memberType(clazztype, descriptor))) {
2226 found = true;
2227 }
2228 }
2229 if (found && count == 1) {
2230 log.note(tree.def, "potential.lambda.found");
2231 }
2232 }
2233 }
2235 private void checkForDeclarationAnnotations(List<? extends JCAnnotation> annotations,
2236 Symbol sym) {
2237 // Ensure that no declaration annotations are present.
2238 // Note that a tree type might be an AnnotatedType with
2239 // empty annotations, if only declaration annotations were given.
2240 // This method will raise an error for such a type.
2241 for (JCAnnotation ai : annotations) {
2242 if (TypeAnnotations.annotationType(syms, names, ai.attribute, sym) == TypeAnnotations.AnnotationType.DECLARATION) {
2243 log.error(ai.pos(), "annotation.type.not.applicable");
2244 }
2245 }
2246 }
2249 /** Make an attributed null check tree.
2250 */
2251 public JCExpression makeNullCheck(JCExpression arg) {
2252 // optimization: X.this is never null; skip null check
2253 Name name = TreeInfo.name(arg);
2254 if (name == names._this || name == names._super) return arg;
2256 JCTree.Tag optag = NULLCHK;
2257 JCUnary tree = make.at(arg.pos).Unary(optag, arg);
2258 tree.operator = syms.nullcheck;
2259 tree.type = arg.type;
2260 return tree;
2261 }
2263 public void visitNewArray(JCNewArray tree) {
2264 Type owntype = types.createErrorType(tree.type);
2265 Env<AttrContext> localEnv = env.dup(tree);
2266 Type elemtype;
2267 if (tree.elemtype != null) {
2268 elemtype = attribType(tree.elemtype, localEnv);
2269 chk.validate(tree.elemtype, localEnv);
2270 owntype = elemtype;
2271 for (List<JCExpression> l = tree.dims; l.nonEmpty(); l = l.tail) {
2272 attribExpr(l.head, localEnv, syms.intType);
2273 owntype = new ArrayType(owntype, syms.arrayClass);
2274 }
2275 if (tree.elemtype.hasTag(ANNOTATED_TYPE)) {
2276 checkForDeclarationAnnotations(((JCAnnotatedType) tree.elemtype).annotations,
2277 tree.elemtype.type.tsym);
2278 }
2279 } else {
2280 // we are seeing an untyped aggregate { ... }
2281 // this is allowed only if the prototype is an array
2282 if (pt().hasTag(ARRAY)) {
2283 elemtype = types.elemtype(pt());
2284 } else {
2285 if (!pt().hasTag(ERROR)) {
2286 log.error(tree.pos(), "illegal.initializer.for.type",
2287 pt());
2288 }
2289 elemtype = types.createErrorType(pt());
2290 }
2291 }
2292 if (tree.elems != null) {
2293 attribExprs(tree.elems, localEnv, elemtype);
2294 owntype = new ArrayType(elemtype, syms.arrayClass);
2295 }
2296 if (!types.isReifiable(elemtype))
2297 log.error(tree.pos(), "generic.array.creation");
2298 result = check(tree, owntype, VAL, resultInfo);
2299 }
2301 /*
2302 * A lambda expression can only be attributed when a target-type is available.
2303 * In addition, if the target-type is that of a functional interface whose
2304 * descriptor contains inference variables in argument position the lambda expression
2305 * is 'stuck' (see DeferredAttr).
2306 */
2307 @Override
2308 public void visitLambda(final JCLambda that) {
2309 if (pt().isErroneous() || (pt().hasTag(NONE) && pt() != Type.recoveryType)) {
2310 if (pt().hasTag(NONE)) {
2311 //lambda only allowed in assignment or method invocation/cast context
2312 log.error(that.pos(), "unexpected.lambda");
2313 }
2314 result = that.type = types.createErrorType(pt());
2315 return;
2316 }
2317 //create an environment for attribution of the lambda expression
2318 final Env<AttrContext> localEnv = lambdaEnv(that, env);
2319 boolean needsRecovery =
2320 resultInfo.checkContext.deferredAttrContext().mode == DeferredAttr.AttrMode.CHECK;
2321 try {
2322 Type target = pt();
2323 List<Type> explicitParamTypes = null;
2324 if (that.paramKind == JCLambda.ParameterKind.EXPLICIT) {
2325 //attribute lambda parameters
2326 attribStats(that.params, localEnv);
2327 explicitParamTypes = TreeInfo.types(that.params);
2328 target = infer.instantiateFunctionalInterface(that, target, explicitParamTypes, resultInfo.checkContext);
2329 }
2331 Type lambdaType;
2332 if (pt() != Type.recoveryType) {
2333 target = targetChecker.visit(target, that);
2334 lambdaType = types.findDescriptorType(target);
2335 } else {
2336 target = Type.recoveryType;
2337 lambdaType = fallbackDescriptorType(that);
2338 }
2340 setFunctionalInfo(localEnv, that, pt(), lambdaType, target, resultInfo.checkContext);
2342 if (lambdaType.hasTag(FORALL)) {
2343 //lambda expression target desc cannot be a generic method
2344 resultInfo.checkContext.report(that, diags.fragment("invalid.generic.lambda.target",
2345 lambdaType, kindName(target.tsym), target.tsym));
2346 result = that.type = types.createErrorType(pt());
2347 return;
2348 }
2350 if (that.paramKind == JCLambda.ParameterKind.IMPLICIT) {
2351 //add param type info in the AST
2352 List<Type> actuals = lambdaType.getParameterTypes();
2353 List<JCVariableDecl> params = that.params;
2355 boolean arityMismatch = false;
2357 while (params.nonEmpty()) {
2358 if (actuals.isEmpty()) {
2359 //not enough actuals to perform lambda parameter inference
2360 arityMismatch = true;
2361 }
2362 //reset previously set info
2363 Type argType = arityMismatch ?
2364 syms.errType :
2365 actuals.head;
2366 params.head.vartype = make.at(params.head).Type(argType);
2367 params.head.sym = null;
2368 actuals = actuals.isEmpty() ?
2369 actuals :
2370 actuals.tail;
2371 params = params.tail;
2372 }
2374 //attribute lambda parameters
2375 attribStats(that.params, localEnv);
2377 if (arityMismatch) {
2378 resultInfo.checkContext.report(that, diags.fragment("incompatible.arg.types.in.lambda"));
2379 result = that.type = types.createErrorType(target);
2380 return;
2381 }
2382 }
2384 //from this point on, no recovery is needed; if we are in assignment context
2385 //we will be able to attribute the whole lambda body, regardless of errors;
2386 //if we are in a 'check' method context, and the lambda is not compatible
2387 //with the target-type, it will be recovered anyway in Attr.checkId
2388 needsRecovery = false;
2390 FunctionalReturnContext funcContext = that.getBodyKind() == JCLambda.BodyKind.EXPRESSION ?
2391 new ExpressionLambdaReturnContext((JCExpression)that.getBody(), resultInfo.checkContext) :
2392 new FunctionalReturnContext(resultInfo.checkContext);
2394 ResultInfo bodyResultInfo = lambdaType.getReturnType() == Type.recoveryType ?
2395 recoveryInfo :
2396 new ResultInfo(VAL, lambdaType.getReturnType(), funcContext);
2397 localEnv.info.returnResult = bodyResultInfo;
2399 if (that.getBodyKind() == JCLambda.BodyKind.EXPRESSION) {
2400 attribTree(that.getBody(), localEnv, bodyResultInfo);
2401 } else {
2402 JCBlock body = (JCBlock)that.body;
2403 attribStats(body.stats, localEnv);
2404 }
2406 result = check(that, target, VAL, resultInfo);
2408 boolean isSpeculativeRound =
2409 resultInfo.checkContext.deferredAttrContext().mode == DeferredAttr.AttrMode.SPECULATIVE;
2411 preFlow(that);
2412 flow.analyzeLambda(env, that, make, isSpeculativeRound);
2414 checkLambdaCompatible(that, lambdaType, resultInfo.checkContext, isSpeculativeRound);
2416 if (!isSpeculativeRound) {
2417 checkAccessibleTypes(that, localEnv, resultInfo.checkContext.inferenceContext(), lambdaType, target);
2418 }
2419 result = check(that, target, VAL, resultInfo);
2420 } catch (Types.FunctionDescriptorLookupError ex) {
2421 JCDiagnostic cause = ex.getDiagnostic();
2422 resultInfo.checkContext.report(that, cause);
2423 result = that.type = types.createErrorType(pt());
2424 return;
2425 } finally {
2426 localEnv.info.scope.leave();
2427 if (needsRecovery) {
2428 attribTree(that, env, recoveryInfo);
2429 }
2430 }
2431 }
2432 //where
2433 void preFlow(JCLambda tree) {
2434 new PostAttrAnalyzer() {
2435 @Override
2436 public void scan(JCTree tree) {
2437 if (tree == null ||
2438 (tree.type != null &&
2439 tree.type == Type.stuckType)) {
2440 //don't touch stuck expressions!
2441 return;
2442 }
2443 super.scan(tree);
2444 }
2445 }.scan(tree);
2446 }
2448 Types.MapVisitor<DiagnosticPosition> targetChecker = new Types.MapVisitor<DiagnosticPosition>() {
2450 @Override
2451 public Type visitClassType(ClassType t, DiagnosticPosition pos) {
2452 return t.isCompound() ?
2453 visitIntersectionClassType((IntersectionClassType)t, pos) : t;
2454 }
2456 public Type visitIntersectionClassType(IntersectionClassType ict, DiagnosticPosition pos) {
2457 Symbol desc = types.findDescriptorSymbol(makeNotionalInterface(ict));
2458 Type target = null;
2459 for (Type bound : ict.getExplicitComponents()) {
2460 TypeSymbol boundSym = bound.tsym;
2461 if (types.isFunctionalInterface(boundSym) &&
2462 types.findDescriptorSymbol(boundSym) == desc) {
2463 target = bound;
2464 } else if (!boundSym.isInterface() || (boundSym.flags() & ANNOTATION) != 0) {
2465 //bound must be an interface
2466 reportIntersectionError(pos, "not.an.intf.component", boundSym);
2467 }
2468 }
2469 return target != null ?
2470 target :
2471 ict.getExplicitComponents().head; //error recovery
2472 }
2474 private TypeSymbol makeNotionalInterface(IntersectionClassType ict) {
2475 ListBuffer<Type> targs = ListBuffer.lb();
2476 ListBuffer<Type> supertypes = ListBuffer.lb();
2477 for (Type i : ict.interfaces_field) {
2478 if (i.isParameterized()) {
2479 targs.appendList(i.tsym.type.allparams());
2480 }
2481 supertypes.append(i.tsym.type);
2482 }
2483 IntersectionClassType notionalIntf =
2484 (IntersectionClassType)types.makeCompoundType(supertypes.toList());
2485 notionalIntf.allparams_field = targs.toList();
2486 notionalIntf.tsym.flags_field |= INTERFACE;
2487 return notionalIntf.tsym;
2488 }
2490 private void reportIntersectionError(DiagnosticPosition pos, String key, Object... args) {
2491 resultInfo.checkContext.report(pos, diags.fragment("bad.intersection.target.for.functional.expr",
2492 diags.fragment(key, args)));
2493 }
2494 };
2496 private Type fallbackDescriptorType(JCExpression tree) {
2497 switch (tree.getTag()) {
2498 case LAMBDA:
2499 JCLambda lambda = (JCLambda)tree;
2500 List<Type> argtypes = List.nil();
2501 for (JCVariableDecl param : lambda.params) {
2502 argtypes = param.vartype != null ?
2503 argtypes.append(param.vartype.type) :
2504 argtypes.append(syms.errType);
2505 }
2506 return new MethodType(argtypes, Type.recoveryType,
2507 List.of(syms.throwableType), syms.methodClass);
2508 case REFERENCE:
2509 return new MethodType(List.<Type>nil(), Type.recoveryType,
2510 List.of(syms.throwableType), syms.methodClass);
2511 default:
2512 Assert.error("Cannot get here!");
2513 }
2514 return null;
2515 }
2517 private void checkAccessibleTypes(final DiagnosticPosition pos, final Env<AttrContext> env,
2518 final InferenceContext inferenceContext, final Type... ts) {
2519 checkAccessibleTypes(pos, env, inferenceContext, List.from(ts));
2520 }
2522 private void checkAccessibleTypes(final DiagnosticPosition pos, final Env<AttrContext> env,
2523 final InferenceContext inferenceContext, final List<Type> ts) {
2524 if (inferenceContext.free(ts)) {
2525 inferenceContext.addFreeTypeListener(ts, new FreeTypeListener() {
2526 @Override
2527 public void typesInferred(InferenceContext inferenceContext) {
2528 checkAccessibleTypes(pos, env, inferenceContext, inferenceContext.asInstTypes(ts));
2529 }
2530 });
2531 } else {
2532 for (Type t : ts) {
2533 rs.checkAccessibleType(env, t);
2534 }
2535 }
2536 }
2538 /**
2539 * Lambda/method reference have a special check context that ensures
2540 * that i.e. a lambda return type is compatible with the expected
2541 * type according to both the inherited context and the assignment
2542 * context.
2543 */
2544 class FunctionalReturnContext extends Check.NestedCheckContext {
2546 FunctionalReturnContext(CheckContext enclosingContext) {
2547 super(enclosingContext);
2548 }
2550 @Override
2551 public boolean compatible(Type found, Type req, Warner warn) {
2552 //return type must be compatible in both current context and assignment context
2553 return chk.basicHandler.compatible(found, inferenceContext().asFree(req), warn);
2554 }
2556 @Override
2557 public void report(DiagnosticPosition pos, JCDiagnostic details) {
2558 enclosingContext.report(pos, diags.fragment("incompatible.ret.type.in.lambda", details));
2559 }
2560 }
2562 class ExpressionLambdaReturnContext extends FunctionalReturnContext {
2564 JCExpression expr;
2566 ExpressionLambdaReturnContext(JCExpression expr, CheckContext enclosingContext) {
2567 super(enclosingContext);
2568 this.expr = expr;
2569 }
2571 @Override
2572 public boolean compatible(Type found, Type req, Warner warn) {
2573 //a void return is compatible with an expression statement lambda
2574 return TreeInfo.isExpressionStatement(expr) && req.hasTag(VOID) ||
2575 super.compatible(found, req, warn);
2576 }
2577 }
2579 /**
2580 * Lambda compatibility. Check that given return types, thrown types, parameter types
2581 * are compatible with the expected functional interface descriptor. This means that:
2582 * (i) parameter types must be identical to those of the target descriptor; (ii) return
2583 * types must be compatible with the return type of the expected descriptor;
2584 * (iii) finish inference of thrown types if required.
2585 */
2586 private void checkLambdaCompatible(JCLambda tree, Type descriptor, CheckContext checkContext, boolean speculativeAttr) {
2587 Type returnType = checkContext.inferenceContext().asFree(descriptor.getReturnType());
2589 //return values have already been checked - but if lambda has no return
2590 //values, we must ensure that void/value compatibility is correct;
2591 //this amounts at checking that, if a lambda body can complete normally,
2592 //the descriptor's return type must be void
2593 if (tree.getBodyKind() == JCLambda.BodyKind.STATEMENT && tree.canCompleteNormally &&
2594 !returnType.hasTag(VOID) && returnType != Type.recoveryType) {
2595 checkContext.report(tree, diags.fragment("incompatible.ret.type.in.lambda",
2596 diags.fragment("missing.ret.val", returnType)));
2597 }
2599 List<Type> argTypes = checkContext.inferenceContext().asFree(descriptor.getParameterTypes());
2600 if (!types.isSameTypes(argTypes, TreeInfo.types(tree.params))) {
2601 checkContext.report(tree, diags.fragment("incompatible.arg.types.in.lambda"));
2602 }
2604 if (!speculativeAttr) {
2605 List<Type> thrownTypes = checkContext.inferenceContext().asFree(descriptor.getThrownTypes());
2606 chk.unhandled(tree.inferredThrownTypes == null ? List.<Type>nil() : tree.inferredThrownTypes, thrownTypes);
2607 }
2608 }
2610 private Env<AttrContext> lambdaEnv(JCLambda that, Env<AttrContext> env) {
2611 Env<AttrContext> lambdaEnv;
2612 Symbol owner = env.info.scope.owner;
2613 if (owner.kind == VAR && owner.owner.kind == TYP) {
2614 //field initializer
2615 lambdaEnv = env.dup(that, env.info.dup(env.info.scope.dupUnshared()));
2616 lambdaEnv.info.scope.owner =
2617 new MethodSymbol((owner.flags() & STATIC) | BLOCK, names.empty, null,
2618 env.info.scope.owner);
2619 } else {
2620 lambdaEnv = env.dup(that, env.info.dup(env.info.scope.dup()));
2621 }
2622 return lambdaEnv;
2623 }
2625 @Override
2626 public void visitReference(final JCMemberReference that) {
2627 if (pt().isErroneous() || (pt().hasTag(NONE) && pt() != Type.recoveryType)) {
2628 if (pt().hasTag(NONE)) {
2629 //method reference only allowed in assignment or method invocation/cast context
2630 log.error(that.pos(), "unexpected.mref");
2631 }
2632 result = that.type = types.createErrorType(pt());
2633 return;
2634 }
2635 final Env<AttrContext> localEnv = env.dup(that);
2636 try {
2637 //attribute member reference qualifier - if this is a constructor
2638 //reference, the expected kind must be a type
2639 Type exprType = attribTree(that.expr, env, memberReferenceQualifierResult(that));
2641 if (that.getMode() == JCMemberReference.ReferenceMode.NEW) {
2642 exprType = chk.checkConstructorRefType(that.expr, exprType);
2643 }
2645 if (exprType.isErroneous()) {
2646 //if the qualifier expression contains problems,
2647 //give up attribution of method reference
2648 result = that.type = exprType;
2649 return;
2650 }
2652 if (TreeInfo.isStaticSelector(that.expr, names)) {
2653 //if the qualifier is a type, validate it; raw warning check is
2654 //omitted as we don't know at this stage as to whether this is a
2655 //raw selector (because of inference)
2656 chk.validate(that.expr, env, false);
2657 }
2659 //attrib type-arguments
2660 List<Type> typeargtypes = List.nil();
2661 if (that.typeargs != null) {
2662 typeargtypes = attribTypes(that.typeargs, localEnv);
2663 }
2665 Type target;
2666 Type desc;
2667 if (pt() != Type.recoveryType) {
2668 target = targetChecker.visit(pt(), that);
2669 desc = types.findDescriptorType(target);
2670 } else {
2671 target = Type.recoveryType;
2672 desc = fallbackDescriptorType(that);
2673 }
2675 setFunctionalInfo(localEnv, that, pt(), desc, target, resultInfo.checkContext);
2676 List<Type> argtypes = desc.getParameterTypes();
2677 Resolve.MethodCheck referenceCheck = rs.resolveMethodCheck;
2679 if (resultInfo.checkContext.inferenceContext().free(argtypes)) {
2680 referenceCheck = rs.new MethodReferenceCheck(resultInfo.checkContext.inferenceContext());
2681 }
2683 Pair<Symbol, Resolve.ReferenceLookupHelper> refResult = null;
2684 List<Type> saved_undet = resultInfo.checkContext.inferenceContext().save();
2685 try {
2686 refResult = rs.resolveMemberReference(that.pos(), localEnv, that, that.expr.type,
2687 that.name, argtypes, typeargtypes, true, referenceCheck,
2688 resultInfo.checkContext.inferenceContext());
2689 } finally {
2690 resultInfo.checkContext.inferenceContext().rollback(saved_undet);
2691 }
2693 Symbol refSym = refResult.fst;
2694 Resolve.ReferenceLookupHelper lookupHelper = refResult.snd;
2696 if (refSym.kind != MTH) {
2697 boolean targetError;
2698 switch (refSym.kind) {
2699 case ABSENT_MTH:
2700 targetError = false;
2701 break;
2702 case WRONG_MTH:
2703 case WRONG_MTHS:
2704 case AMBIGUOUS:
2705 case HIDDEN:
2706 case STATICERR:
2707 case MISSING_ENCL:
2708 targetError = true;
2709 break;
2710 default:
2711 Assert.error("unexpected result kind " + refSym.kind);
2712 targetError = false;
2713 }
2715 JCDiagnostic detailsDiag = ((Resolve.ResolveError)refSym).getDiagnostic(JCDiagnostic.DiagnosticType.FRAGMENT,
2716 that, exprType.tsym, exprType, that.name, argtypes, typeargtypes);
2718 JCDiagnostic.DiagnosticType diagKind = targetError ?
2719 JCDiagnostic.DiagnosticType.FRAGMENT : JCDiagnostic.DiagnosticType.ERROR;
2721 JCDiagnostic diag = diags.create(diagKind, log.currentSource(), that,
2722 "invalid.mref", Kinds.kindName(that.getMode()), detailsDiag);
2724 if (targetError && target == Type.recoveryType) {
2725 //a target error doesn't make sense during recovery stage
2726 //as we don't know what actual parameter types are
2727 result = that.type = target;
2728 return;
2729 } else {
2730 if (targetError) {
2731 resultInfo.checkContext.report(that, diag);
2732 } else {
2733 log.report(diag);
2734 }
2735 result = that.type = types.createErrorType(target);
2736 return;
2737 }
2738 }
2740 that.sym = refSym.baseSymbol();
2741 that.kind = lookupHelper.referenceKind(that.sym);
2742 that.ownerAccessible = rs.isAccessible(localEnv, that.sym.enclClass());
2744 if (desc.getReturnType() == Type.recoveryType) {
2745 // stop here
2746 result = that.type = target;
2747 return;
2748 }
2750 if (resultInfo.checkContext.deferredAttrContext().mode == AttrMode.CHECK) {
2752 if (that.getMode() == ReferenceMode.INVOKE &&
2753 TreeInfo.isStaticSelector(that.expr, names) &&
2754 that.kind.isUnbound() &&
2755 !desc.getParameterTypes().head.isParameterized()) {
2756 chk.checkRaw(that.expr, localEnv);
2757 }
2759 if (!that.kind.isUnbound() &&
2760 that.getMode() == ReferenceMode.INVOKE &&
2761 TreeInfo.isStaticSelector(that.expr, names) &&
2762 !that.sym.isStatic()) {
2763 log.error(that.expr.pos(), "invalid.mref", Kinds.kindName(that.getMode()),
2764 diags.fragment("non-static.cant.be.ref", Kinds.kindName(refSym), refSym));
2765 result = that.type = types.createErrorType(target);
2766 return;
2767 }
2769 if (that.kind.isUnbound() &&
2770 that.getMode() == ReferenceMode.INVOKE &&
2771 TreeInfo.isStaticSelector(that.expr, names) &&
2772 that.sym.isStatic()) {
2773 log.error(that.expr.pos(), "invalid.mref", Kinds.kindName(that.getMode()),
2774 diags.fragment("static.method.in.unbound.lookup", Kinds.kindName(refSym), refSym));
2775 result = that.type = types.createErrorType(target);
2776 return;
2777 }
2779 if (that.sym.isStatic() && TreeInfo.isStaticSelector(that.expr, names) &&
2780 exprType.getTypeArguments().nonEmpty()) {
2781 //static ref with class type-args
2782 log.error(that.expr.pos(), "invalid.mref", Kinds.kindName(that.getMode()),
2783 diags.fragment("static.mref.with.targs"));
2784 result = that.type = types.createErrorType(target);
2785 return;
2786 }
2788 if (that.sym.isStatic() && !TreeInfo.isStaticSelector(that.expr, names) &&
2789 !that.kind.isUnbound()) {
2790 //no static bound mrefs
2791 log.error(that.expr.pos(), "invalid.mref", Kinds.kindName(that.getMode()),
2792 diags.fragment("static.bound.mref"));
2793 result = that.type = types.createErrorType(target);
2794 return;
2795 }
2797 if (!refSym.isStatic() && that.kind == JCMemberReference.ReferenceKind.SUPER) {
2798 // Check that super-qualified symbols are not abstract (JLS)
2799 rs.checkNonAbstract(that.pos(), that.sym);
2800 }
2801 }
2803 ResultInfo checkInfo =
2804 resultInfo.dup(newMethodTemplate(
2805 desc.getReturnType().hasTag(VOID) ? Type.noType : desc.getReturnType(),
2806 that.kind.isUnbound() ? argtypes.tail : argtypes, typeargtypes));
2808 Type refType = checkId(that, lookupHelper.site, refSym, localEnv, checkInfo);
2810 if (that.kind.isUnbound() &&
2811 resultInfo.checkContext.inferenceContext().free(argtypes.head)) {
2812 //re-generate inference constraints for unbound receiver
2813 if (!types.isSubtype(resultInfo.checkContext.inferenceContext().asFree(argtypes.head), exprType)) {
2814 //cannot happen as this has already been checked - we just need
2815 //to regenerate the inference constraints, as that has been lost
2816 //as a result of the call to inferenceContext.save()
2817 Assert.error("Can't get here");
2818 }
2819 }
2821 if (!refType.isErroneous()) {
2822 refType = types.createMethodTypeWithReturn(refType,
2823 adjustMethodReturnType(lookupHelper.site, that.name, checkInfo.pt.getParameterTypes(), refType.getReturnType()));
2824 }
2826 //go ahead with standard method reference compatibility check - note that param check
2827 //is a no-op (as this has been taken care during method applicability)
2828 boolean isSpeculativeRound =
2829 resultInfo.checkContext.deferredAttrContext().mode == DeferredAttr.AttrMode.SPECULATIVE;
2830 checkReferenceCompatible(that, desc, refType, resultInfo.checkContext, isSpeculativeRound);
2831 if (!isSpeculativeRound) {
2832 checkAccessibleTypes(that, localEnv, resultInfo.checkContext.inferenceContext(), desc, target);
2833 }
2834 result = check(that, target, VAL, resultInfo);
2835 } catch (Types.FunctionDescriptorLookupError ex) {
2836 JCDiagnostic cause = ex.getDiagnostic();
2837 resultInfo.checkContext.report(that, cause);
2838 result = that.type = types.createErrorType(pt());
2839 return;
2840 }
2841 }
2842 //where
2843 ResultInfo memberReferenceQualifierResult(JCMemberReference tree) {
2844 //if this is a constructor reference, the expected kind must be a type
2845 return new ResultInfo(tree.getMode() == ReferenceMode.INVOKE ? VAL | TYP : TYP, Type.noType);
2846 }
2849 @SuppressWarnings("fallthrough")
2850 void checkReferenceCompatible(JCMemberReference tree, Type descriptor, Type refType, CheckContext checkContext, boolean speculativeAttr) {
2851 Type returnType = checkContext.inferenceContext().asFree(descriptor.getReturnType());
2853 Type resType;
2854 switch (tree.getMode()) {
2855 case NEW:
2856 if (!tree.expr.type.isRaw()) {
2857 resType = tree.expr.type;
2858 break;
2859 }
2860 default:
2861 resType = refType.getReturnType();
2862 }
2864 Type incompatibleReturnType = resType;
2866 if (returnType.hasTag(VOID)) {
2867 incompatibleReturnType = null;
2868 }
2870 if (!returnType.hasTag(VOID) && !resType.hasTag(VOID)) {
2871 if (resType.isErroneous() ||
2872 new FunctionalReturnContext(checkContext).compatible(resType, returnType, types.noWarnings)) {
2873 incompatibleReturnType = null;
2874 }
2875 }
2877 if (incompatibleReturnType != null) {
2878 checkContext.report(tree, diags.fragment("incompatible.ret.type.in.mref",
2879 diags.fragment("inconvertible.types", resType, descriptor.getReturnType())));
2880 }
2882 if (!speculativeAttr) {
2883 List<Type> thrownTypes = checkContext.inferenceContext().asFree(descriptor.getThrownTypes());
2884 if (chk.unhandled(refType.getThrownTypes(), thrownTypes).nonEmpty()) {
2885 log.error(tree, "incompatible.thrown.types.in.mref", refType.getThrownTypes());
2886 }
2887 }
2888 }
2890 /**
2891 * Set functional type info on the underlying AST. Note: as the target descriptor
2892 * might contain inference variables, we might need to register an hook in the
2893 * current inference context.
2894 */
2895 private void setFunctionalInfo(final Env<AttrContext> env, final JCFunctionalExpression fExpr,
2896 final Type pt, final Type descriptorType, final Type primaryTarget, final CheckContext checkContext) {
2897 if (checkContext.inferenceContext().free(descriptorType)) {
2898 checkContext.inferenceContext().addFreeTypeListener(List.of(pt, descriptorType), new FreeTypeListener() {
2899 public void typesInferred(InferenceContext inferenceContext) {
2900 setFunctionalInfo(env, fExpr, pt, inferenceContext.asInstType(descriptorType),
2901 inferenceContext.asInstType(primaryTarget), checkContext);
2902 }
2903 });
2904 } else {
2905 ListBuffer<Type> targets = ListBuffer.lb();
2906 if (pt.hasTag(CLASS)) {
2907 if (pt.isCompound()) {
2908 targets.append(types.removeWildcards(primaryTarget)); //this goes first
2909 for (Type t : ((IntersectionClassType)pt()).interfaces_field) {
2910 if (t != primaryTarget) {
2911 targets.append(types.removeWildcards(t));
2912 }
2913 }
2914 } else {
2915 targets.append(types.removeWildcards(primaryTarget));
2916 }
2917 }
2918 fExpr.targets = targets.toList();
2919 if (checkContext.deferredAttrContext().mode == DeferredAttr.AttrMode.CHECK &&
2920 pt != Type.recoveryType) {
2921 //check that functional interface class is well-formed
2922 ClassSymbol csym = types.makeFunctionalInterfaceClass(env,
2923 names.empty, List.of(fExpr.targets.head), ABSTRACT);
2924 if (csym != null) {
2925 chk.checkImplementations(env.tree, csym, csym);
2926 }
2927 }
2928 }
2929 }
2931 public void visitParens(JCParens tree) {
2932 Type owntype = attribTree(tree.expr, env, resultInfo);
2933 result = check(tree, owntype, pkind(), resultInfo);
2934 Symbol sym = TreeInfo.symbol(tree);
2935 if (sym != null && (sym.kind&(TYP|PCK)) != 0)
2936 log.error(tree.pos(), "illegal.start.of.type");
2937 }
2939 public void visitAssign(JCAssign tree) {
2940 Type owntype = attribTree(tree.lhs, env.dup(tree), varInfo);
2941 Type capturedType = capture(owntype);
2942 attribExpr(tree.rhs, env, owntype);
2943 result = check(tree, capturedType, VAL, resultInfo);
2944 }
2946 public void visitAssignop(JCAssignOp tree) {
2947 // Attribute arguments.
2948 Type owntype = attribTree(tree.lhs, env, varInfo);
2949 Type operand = attribExpr(tree.rhs, env);
2950 // Find operator.
2951 Symbol operator = tree.operator = rs.resolveBinaryOperator(
2952 tree.pos(), tree.getTag().noAssignOp(), env,
2953 owntype, operand);
2955 if (operator.kind == MTH &&
2956 !owntype.isErroneous() &&
2957 !operand.isErroneous()) {
2958 chk.checkOperator(tree.pos(),
2959 (OperatorSymbol)operator,
2960 tree.getTag().noAssignOp(),
2961 owntype,
2962 operand);
2963 chk.checkDivZero(tree.rhs.pos(), operator, operand);
2964 chk.checkCastable(tree.rhs.pos(),
2965 operator.type.getReturnType(),
2966 owntype);
2967 }
2968 result = check(tree, owntype, VAL, resultInfo);
2969 }
2971 public void visitUnary(JCUnary tree) {
2972 // Attribute arguments.
2973 Type argtype = (tree.getTag().isIncOrDecUnaryOp())
2974 ? attribTree(tree.arg, env, varInfo)
2975 : chk.checkNonVoid(tree.arg.pos(), attribExpr(tree.arg, env));
2977 // Find operator.
2978 Symbol operator = tree.operator =
2979 rs.resolveUnaryOperator(tree.pos(), tree.getTag(), env, argtype);
2981 Type owntype = types.createErrorType(tree.type);
2982 if (operator.kind == MTH &&
2983 !argtype.isErroneous()) {
2984 owntype = (tree.getTag().isIncOrDecUnaryOp())
2985 ? tree.arg.type
2986 : operator.type.getReturnType();
2987 int opc = ((OperatorSymbol)operator).opcode;
2989 // If the argument is constant, fold it.
2990 if (argtype.constValue() != null) {
2991 Type ctype = cfolder.fold1(opc, argtype);
2992 if (ctype != null) {
2993 owntype = cfolder.coerce(ctype, owntype);
2995 // Remove constant types from arguments to
2996 // conserve space. The parser will fold concatenations
2997 // of string literals; the code here also
2998 // gets rid of intermediate results when some of the
2999 // operands are constant identifiers.
3000 if (tree.arg.type.tsym == syms.stringType.tsym) {
3001 tree.arg.type = syms.stringType;
3002 }
3003 }
3004 }
3005 }
3006 result = check(tree, owntype, VAL, resultInfo);
3007 }
3009 public void visitBinary(JCBinary tree) {
3010 // Attribute arguments.
3011 Type left = chk.checkNonVoid(tree.lhs.pos(), attribExpr(tree.lhs, env));
3012 Type right = chk.checkNonVoid(tree.lhs.pos(), attribExpr(tree.rhs, env));
3014 // Find operator.
3015 Symbol operator = tree.operator =
3016 rs.resolveBinaryOperator(tree.pos(), tree.getTag(), env, left, right);
3018 Type owntype = types.createErrorType(tree.type);
3019 if (operator.kind == MTH &&
3020 !left.isErroneous() &&
3021 !right.isErroneous()) {
3022 owntype = operator.type.getReturnType();
3023 // This will figure out when unboxing can happen and
3024 // choose the right comparison operator.
3025 int opc = chk.checkOperator(tree.lhs.pos(),
3026 (OperatorSymbol)operator,
3027 tree.getTag(),
3028 left,
3029 right);
3031 // If both arguments are constants, fold them.
3032 if (left.constValue() != null && right.constValue() != null) {
3033 Type ctype = cfolder.fold2(opc, left, right);
3034 if (ctype != null) {
3035 owntype = cfolder.coerce(ctype, owntype);
3037 // Remove constant types from arguments to
3038 // conserve space. The parser will fold concatenations
3039 // of string literals; the code here also
3040 // gets rid of intermediate results when some of the
3041 // operands are constant identifiers.
3042 if (tree.lhs.type.tsym == syms.stringType.tsym) {
3043 tree.lhs.type = syms.stringType;
3044 }
3045 if (tree.rhs.type.tsym == syms.stringType.tsym) {
3046 tree.rhs.type = syms.stringType;
3047 }
3048 }
3049 }
3051 // Check that argument types of a reference ==, != are
3052 // castable to each other, (JLS 15.21). Note: unboxing
3053 // comparisons will not have an acmp* opc at this point.
3054 if ((opc == ByteCodes.if_acmpeq || opc == ByteCodes.if_acmpne)) {
3055 if (!types.isEqualityComparable(left, right,
3056 new Warner(tree.pos()))) {
3057 log.error(tree.pos(), "incomparable.types", left, right);
3058 }
3059 }
3061 chk.checkDivZero(tree.rhs.pos(), operator, right);
3062 }
3063 result = check(tree, owntype, VAL, resultInfo);
3064 }
3066 public void visitTypeCast(final JCTypeCast tree) {
3067 Type clazztype = attribType(tree.clazz, env);
3068 chk.validate(tree.clazz, env, false);
3069 //a fresh environment is required for 292 inference to work properly ---
3070 //see Infer.instantiatePolymorphicSignatureInstance()
3071 Env<AttrContext> localEnv = env.dup(tree);
3072 //should we propagate the target type?
3073 final ResultInfo castInfo;
3074 JCExpression expr = TreeInfo.skipParens(tree.expr);
3075 boolean isPoly = allowPoly && (expr.hasTag(LAMBDA) || expr.hasTag(REFERENCE));
3076 if (isPoly) {
3077 //expression is a poly - we need to propagate target type info
3078 castInfo = new ResultInfo(VAL, clazztype, new Check.NestedCheckContext(resultInfo.checkContext) {
3079 @Override
3080 public boolean compatible(Type found, Type req, Warner warn) {
3081 return types.isCastable(found, req, warn);
3082 }
3083 });
3084 } else {
3085 //standalone cast - target-type info is not propagated
3086 castInfo = unknownExprInfo;
3087 }
3088 Type exprtype = attribTree(tree.expr, localEnv, castInfo);
3089 Type owntype = isPoly ? clazztype : chk.checkCastable(tree.expr.pos(), exprtype, clazztype);
3090 if (exprtype.constValue() != null)
3091 owntype = cfolder.coerce(exprtype, owntype);
3092 result = check(tree, capture(owntype), VAL, resultInfo);
3093 if (!isPoly)
3094 chk.checkRedundantCast(localEnv, tree);
3095 }
3097 public void visitTypeTest(JCInstanceOf tree) {
3098 Type exprtype = chk.checkNullOrRefType(
3099 tree.expr.pos(), attribExpr(tree.expr, env));
3100 Type clazztype = chk.checkReifiableReferenceType(
3101 tree.clazz.pos(), attribType(tree.clazz, env));
3102 chk.validate(tree.clazz, env, false);
3103 chk.checkCastable(tree.expr.pos(), exprtype, clazztype);
3104 result = check(tree, syms.booleanType, VAL, resultInfo);
3105 }
3107 public void visitIndexed(JCArrayAccess tree) {
3108 Type owntype = types.createErrorType(tree.type);
3109 Type atype = attribExpr(tree.indexed, env);
3110 attribExpr(tree.index, env, syms.intType);
3111 if (types.isArray(atype))
3112 owntype = types.elemtype(atype);
3113 else if (!atype.hasTag(ERROR))
3114 log.error(tree.pos(), "array.req.but.found", atype);
3115 if ((pkind() & VAR) == 0) owntype = capture(owntype);
3116 result = check(tree, owntype, VAR, resultInfo);
3117 }
3119 public void visitIdent(JCIdent tree) {
3120 Symbol sym;
3122 // Find symbol
3123 if (pt().hasTag(METHOD) || pt().hasTag(FORALL)) {
3124 // If we are looking for a method, the prototype `pt' will be a
3125 // method type with the type of the call's arguments as parameters.
3126 env.info.pendingResolutionPhase = null;
3127 sym = rs.resolveMethod(tree.pos(), env, tree.name, pt().getParameterTypes(), pt().getTypeArguments());
3128 } else if (tree.sym != null && tree.sym.kind != VAR) {
3129 sym = tree.sym;
3130 } else {
3131 sym = rs.resolveIdent(tree.pos(), env, tree.name, pkind());
3132 }
3133 tree.sym = sym;
3135 // (1) Also find the environment current for the class where
3136 // sym is defined (`symEnv').
3137 // Only for pre-tiger versions (1.4 and earlier):
3138 // (2) Also determine whether we access symbol out of an anonymous
3139 // class in a this or super call. This is illegal for instance
3140 // members since such classes don't carry a this$n link.
3141 // (`noOuterThisPath').
3142 Env<AttrContext> symEnv = env;
3143 boolean noOuterThisPath = false;
3144 if (env.enclClass.sym.owner.kind != PCK && // we are in an inner class
3145 (sym.kind & (VAR | MTH | TYP)) != 0 &&
3146 sym.owner.kind == TYP &&
3147 tree.name != names._this && tree.name != names._super) {
3149 // Find environment in which identifier is defined.
3150 while (symEnv.outer != null &&
3151 !sym.isMemberOf(symEnv.enclClass.sym, types)) {
3152 if ((symEnv.enclClass.sym.flags() & NOOUTERTHIS) != 0)
3153 noOuterThisPath = !allowAnonOuterThis;
3154 symEnv = symEnv.outer;
3155 }
3156 }
3158 // If symbol is a variable, ...
3159 if (sym.kind == VAR) {
3160 VarSymbol v = (VarSymbol)sym;
3162 // ..., evaluate its initializer, if it has one, and check for
3163 // illegal forward reference.
3164 checkInit(tree, env, v, false);
3166 // If we are expecting a variable (as opposed to a value), check
3167 // that the variable is assignable in the current environment.
3168 if (pkind() == VAR)
3169 checkAssignable(tree.pos(), v, null, env);
3170 }
3172 // In a constructor body,
3173 // if symbol is a field or instance method, check that it is
3174 // not accessed before the supertype constructor is called.
3175 if ((symEnv.info.isSelfCall || noOuterThisPath) &&
3176 (sym.kind & (VAR | MTH)) != 0 &&
3177 sym.owner.kind == TYP &&
3178 (sym.flags() & STATIC) == 0) {
3179 chk.earlyRefError(tree.pos(), sym.kind == VAR ? sym : thisSym(tree.pos(), env));
3180 }
3181 Env<AttrContext> env1 = env;
3182 if (sym.kind != ERR && sym.kind != TYP && sym.owner != null && sym.owner != env1.enclClass.sym) {
3183 // If the found symbol is inaccessible, then it is
3184 // accessed through an enclosing instance. Locate this
3185 // enclosing instance:
3186 while (env1.outer != null && !rs.isAccessible(env, env1.enclClass.sym.type, sym))
3187 env1 = env1.outer;
3188 }
3189 result = checkId(tree, env1.enclClass.sym.type, sym, env, resultInfo);
3190 }
3192 public void visitSelect(JCFieldAccess tree) {
3193 // Determine the expected kind of the qualifier expression.
3194 int skind = 0;
3195 if (tree.name == names._this || tree.name == names._super ||
3196 tree.name == names._class)
3197 {
3198 skind = TYP;
3199 } else {
3200 if ((pkind() & PCK) != 0) skind = skind | PCK;
3201 if ((pkind() & TYP) != 0) skind = skind | TYP | PCK;
3202 if ((pkind() & (VAL | MTH)) != 0) skind = skind | VAL | TYP;
3203 }
3205 // Attribute the qualifier expression, and determine its symbol (if any).
3206 Type site = attribTree(tree.selected, env, new ResultInfo(skind, Infer.anyPoly));
3207 if ((pkind() & (PCK | TYP)) == 0)
3208 site = capture(site); // Capture field access
3210 // don't allow T.class T[].class, etc
3211 if (skind == TYP) {
3212 Type elt = site;
3213 while (elt.hasTag(ARRAY))
3214 elt = ((ArrayType)elt.unannotatedType()).elemtype;
3215 if (elt.hasTag(TYPEVAR)) {
3216 log.error(tree.pos(), "type.var.cant.be.deref");
3217 result = types.createErrorType(tree.type);
3218 return;
3219 }
3220 }
3222 // If qualifier symbol is a type or `super', assert `selectSuper'
3223 // for the selection. This is relevant for determining whether
3224 // protected symbols are accessible.
3225 Symbol sitesym = TreeInfo.symbol(tree.selected);
3226 boolean selectSuperPrev = env.info.selectSuper;
3227 env.info.selectSuper =
3228 sitesym != null &&
3229 sitesym.name == names._super;
3231 // Determine the symbol represented by the selection.
3232 env.info.pendingResolutionPhase = null;
3233 Symbol sym = selectSym(tree, sitesym, site, env, resultInfo);
3234 if (sym.exists() && !isType(sym) && (pkind() & (PCK | TYP)) != 0) {
3235 site = capture(site);
3236 sym = selectSym(tree, sitesym, site, env, resultInfo);
3237 }
3238 boolean varArgs = env.info.lastResolveVarargs();
3239 tree.sym = sym;
3241 if (site.hasTag(TYPEVAR) && !isType(sym) && sym.kind != ERR) {
3242 while (site.hasTag(TYPEVAR)) site = site.getUpperBound();
3243 site = capture(site);
3244 }
3246 // If that symbol is a variable, ...
3247 if (sym.kind == VAR) {
3248 VarSymbol v = (VarSymbol)sym;
3250 // ..., evaluate its initializer, if it has one, and check for
3251 // illegal forward reference.
3252 checkInit(tree, env, v, true);
3254 // If we are expecting a variable (as opposed to a value), check
3255 // that the variable is assignable in the current environment.
3256 if (pkind() == VAR)
3257 checkAssignable(tree.pos(), v, tree.selected, env);
3258 }
3260 if (sitesym != null &&
3261 sitesym.kind == VAR &&
3262 ((VarSymbol)sitesym).isResourceVariable() &&
3263 sym.kind == MTH &&
3264 sym.name.equals(names.close) &&
3265 sym.overrides(syms.autoCloseableClose, sitesym.type.tsym, types, true) &&
3266 env.info.lint.isEnabled(LintCategory.TRY)) {
3267 log.warning(LintCategory.TRY, tree, "try.explicit.close.call");
3268 }
3270 // Disallow selecting a type from an expression
3271 if (isType(sym) && (sitesym==null || (sitesym.kind&(TYP|PCK)) == 0)) {
3272 tree.type = check(tree.selected, pt(),
3273 sitesym == null ? VAL : sitesym.kind, new ResultInfo(TYP|PCK, pt()));
3274 }
3276 if (isType(sitesym)) {
3277 if (sym.name == names._this) {
3278 // If `C' is the currently compiled class, check that
3279 // C.this' does not appear in a call to a super(...)
3280 if (env.info.isSelfCall &&
3281 site.tsym == env.enclClass.sym) {
3282 chk.earlyRefError(tree.pos(), sym);
3283 }
3284 } else {
3285 // Check if type-qualified fields or methods are static (JLS)
3286 if ((sym.flags() & STATIC) == 0 &&
3287 !env.next.tree.hasTag(REFERENCE) &&
3288 sym.name != names._super &&
3289 (sym.kind == VAR || sym.kind == MTH)) {
3290 rs.accessBase(rs.new StaticError(sym),
3291 tree.pos(), site, sym.name, true);
3292 }
3293 }
3294 } else if (sym.kind != ERR && (sym.flags() & STATIC) != 0 && sym.name != names._class) {
3295 // If the qualified item is not a type and the selected item is static, report
3296 // a warning. Make allowance for the class of an array type e.g. Object[].class)
3297 chk.warnStatic(tree, "static.not.qualified.by.type", Kinds.kindName(sym.kind), sym.owner);
3298 }
3300 // If we are selecting an instance member via a `super', ...
3301 if (env.info.selectSuper && (sym.flags() & STATIC) == 0) {
3303 // Check that super-qualified symbols are not abstract (JLS)
3304 rs.checkNonAbstract(tree.pos(), sym);
3306 if (site.isRaw()) {
3307 // Determine argument types for site.
3308 Type site1 = types.asSuper(env.enclClass.sym.type, site.tsym);
3309 if (site1 != null) site = site1;
3310 }
3311 }
3313 env.info.selectSuper = selectSuperPrev;
3314 result = checkId(tree, site, sym, env, resultInfo);
3315 }
3316 //where
3317 /** Determine symbol referenced by a Select expression,
3318 *
3319 * @param tree The select tree.
3320 * @param site The type of the selected expression,
3321 * @param env The current environment.
3322 * @param resultInfo The current result.
3323 */
3324 private Symbol selectSym(JCFieldAccess tree,
3325 Symbol location,
3326 Type site,
3327 Env<AttrContext> env,
3328 ResultInfo resultInfo) {
3329 DiagnosticPosition pos = tree.pos();
3330 Name name = tree.name;
3331 switch (site.getTag()) {
3332 case PACKAGE:
3333 return rs.accessBase(
3334 rs.findIdentInPackage(env, site.tsym, name, resultInfo.pkind),
3335 pos, location, site, name, true);
3336 case ARRAY:
3337 case CLASS:
3338 if (resultInfo.pt.hasTag(METHOD) || resultInfo.pt.hasTag(FORALL)) {
3339 return rs.resolveQualifiedMethod(
3340 pos, env, location, site, name, resultInfo.pt.getParameterTypes(), resultInfo.pt.getTypeArguments());
3341 } else if (name == names._this || name == names._super) {
3342 return rs.resolveSelf(pos, env, site.tsym, name);
3343 } else if (name == names._class) {
3344 // In this case, we have already made sure in
3345 // visitSelect that qualifier expression is a type.
3346 Type t = syms.classType;
3347 List<Type> typeargs = allowGenerics
3348 ? List.of(types.erasure(site))
3349 : List.<Type>nil();
3350 t = new ClassType(t.getEnclosingType(), typeargs, t.tsym);
3351 return new VarSymbol(
3352 STATIC | PUBLIC | FINAL, names._class, t, site.tsym);
3353 } else {
3354 // We are seeing a plain identifier as selector.
3355 Symbol sym = rs.findIdentInType(env, site, name, resultInfo.pkind);
3356 if ((resultInfo.pkind & ERRONEOUS) == 0)
3357 sym = rs.accessBase(sym, pos, location, site, name, true);
3358 return sym;
3359 }
3360 case WILDCARD:
3361 throw new AssertionError(tree);
3362 case TYPEVAR:
3363 // Normally, site.getUpperBound() shouldn't be null.
3364 // It should only happen during memberEnter/attribBase
3365 // when determining the super type which *must* beac
3366 // done before attributing the type variables. In
3367 // other words, we are seeing this illegal program:
3368 // class B<T> extends A<T.foo> {}
3369 Symbol sym = (site.getUpperBound() != null)
3370 ? selectSym(tree, location, capture(site.getUpperBound()), env, resultInfo)
3371 : null;
3372 if (sym == null) {
3373 log.error(pos, "type.var.cant.be.deref");
3374 return syms.errSymbol;
3375 } else {
3376 Symbol sym2 = (sym.flags() & Flags.PRIVATE) != 0 ?
3377 rs.new AccessError(env, site, sym) :
3378 sym;
3379 rs.accessBase(sym2, pos, location, site, name, true);
3380 return sym;
3381 }
3382 case ERROR:
3383 // preserve identifier names through errors
3384 return types.createErrorType(name, site.tsym, site).tsym;
3385 default:
3386 // The qualifier expression is of a primitive type -- only
3387 // .class is allowed for these.
3388 if (name == names._class) {
3389 // In this case, we have already made sure in Select that
3390 // qualifier expression is a type.
3391 Type t = syms.classType;
3392 Type arg = types.boxedClass(site).type;
3393 t = new ClassType(t.getEnclosingType(), List.of(arg), t.tsym);
3394 return new VarSymbol(
3395 STATIC | PUBLIC | FINAL, names._class, t, site.tsym);
3396 } else {
3397 log.error(pos, "cant.deref", site);
3398 return syms.errSymbol;
3399 }
3400 }
3401 }
3403 /** Determine type of identifier or select expression and check that
3404 * (1) the referenced symbol is not deprecated
3405 * (2) the symbol's type is safe (@see checkSafe)
3406 * (3) if symbol is a variable, check that its type and kind are
3407 * compatible with the prototype and protokind.
3408 * (4) if symbol is an instance field of a raw type,
3409 * which is being assigned to, issue an unchecked warning if its
3410 * type changes under erasure.
3411 * (5) if symbol is an instance method of a raw type, issue an
3412 * unchecked warning if its argument types change under erasure.
3413 * If checks succeed:
3414 * If symbol is a constant, return its constant type
3415 * else if symbol is a method, return its result type
3416 * otherwise return its type.
3417 * Otherwise return errType.
3418 *
3419 * @param tree The syntax tree representing the identifier
3420 * @param site If this is a select, the type of the selected
3421 * expression, otherwise the type of the current class.
3422 * @param sym The symbol representing the identifier.
3423 * @param env The current environment.
3424 * @param resultInfo The expected result
3425 */
3426 Type checkId(JCTree tree,
3427 Type site,
3428 Symbol sym,
3429 Env<AttrContext> env,
3430 ResultInfo resultInfo) {
3431 return (resultInfo.pt.hasTag(FORALL) || resultInfo.pt.hasTag(METHOD)) ?
3432 checkMethodId(tree, site, sym, env, resultInfo) :
3433 checkIdInternal(tree, site, sym, resultInfo.pt, env, resultInfo);
3434 }
3436 Type checkMethodId(JCTree tree,
3437 Type site,
3438 Symbol sym,
3439 Env<AttrContext> env,
3440 ResultInfo resultInfo) {
3441 boolean isPolymorhicSignature =
3442 (sym.baseSymbol().flags() & SIGNATURE_POLYMORPHIC) != 0;
3443 return isPolymorhicSignature ?
3444 checkSigPolyMethodId(tree, site, sym, env, resultInfo) :
3445 checkMethodIdInternal(tree, site, sym, env, resultInfo);
3446 }
3448 Type checkSigPolyMethodId(JCTree tree,
3449 Type site,
3450 Symbol sym,
3451 Env<AttrContext> env,
3452 ResultInfo resultInfo) {
3453 //recover original symbol for signature polymorphic methods
3454 checkMethodIdInternal(tree, site, sym.baseSymbol(), env, resultInfo);
3455 env.info.pendingResolutionPhase = Resolve.MethodResolutionPhase.BASIC;
3456 return sym.type;
3457 }
3459 Type checkMethodIdInternal(JCTree tree,
3460 Type site,
3461 Symbol sym,
3462 Env<AttrContext> env,
3463 ResultInfo resultInfo) {
3464 if ((resultInfo.pkind & POLY) != 0) {
3465 Type pt = resultInfo.pt.map(deferredAttr.new RecoveryDeferredTypeMap(AttrMode.SPECULATIVE, sym, env.info.pendingResolutionPhase));
3466 Type owntype = checkIdInternal(tree, site, sym, pt, env, resultInfo);
3467 resultInfo.pt.map(deferredAttr.new RecoveryDeferredTypeMap(AttrMode.CHECK, sym, env.info.pendingResolutionPhase));
3468 return owntype;
3469 } else {
3470 return checkIdInternal(tree, site, sym, resultInfo.pt, env, resultInfo);
3471 }
3472 }
3474 Type checkIdInternal(JCTree tree,
3475 Type site,
3476 Symbol sym,
3477 Type pt,
3478 Env<AttrContext> env,
3479 ResultInfo resultInfo) {
3480 if (pt.isErroneous()) {
3481 return types.createErrorType(site);
3482 }
3483 Type owntype; // The computed type of this identifier occurrence.
3484 switch (sym.kind) {
3485 case TYP:
3486 // For types, the computed type equals the symbol's type,
3487 // except for two situations:
3488 owntype = sym.type;
3489 if (owntype.hasTag(CLASS)) {
3490 chk.checkForBadAuxiliaryClassAccess(tree.pos(), env, (ClassSymbol)sym);
3491 Type ownOuter = owntype.getEnclosingType();
3493 // (a) If the symbol's type is parameterized, erase it
3494 // because no type parameters were given.
3495 // We recover generic outer type later in visitTypeApply.
3496 if (owntype.tsym.type.getTypeArguments().nonEmpty()) {
3497 owntype = types.erasure(owntype);
3498 }
3500 // (b) If the symbol's type is an inner class, then
3501 // we have to interpret its outer type as a superclass
3502 // of the site type. Example:
3503 //
3504 // class Tree<A> { class Visitor { ... } }
3505 // class PointTree extends Tree<Point> { ... }
3506 // ...PointTree.Visitor...
3507 //
3508 // Then the type of the last expression above is
3509 // Tree<Point>.Visitor.
3510 else if (ownOuter.hasTag(CLASS) && site != ownOuter) {
3511 Type normOuter = site;
3512 if (normOuter.hasTag(CLASS)) {
3513 normOuter = types.asEnclosingSuper(site, ownOuter.tsym);
3514 if (site.isAnnotated()) {
3515 // Propagate any type annotations.
3516 // TODO: should asEnclosingSuper do this?
3517 // Note that the type annotations in site will be updated
3518 // by annotateType. Therefore, modify site instead
3519 // of creating a new AnnotatedType.
3520 ((AnnotatedType)site).underlyingType = normOuter;
3521 normOuter = site;
3522 }
3523 }
3524 if (normOuter == null) // perhaps from an import
3525 normOuter = types.erasure(ownOuter);
3526 if (normOuter != ownOuter)
3527 owntype = new ClassType(
3528 normOuter, List.<Type>nil(), owntype.tsym);
3529 }
3530 }
3531 break;
3532 case VAR:
3533 VarSymbol v = (VarSymbol)sym;
3534 // Test (4): if symbol is an instance field of a raw type,
3535 // which is being assigned to, issue an unchecked warning if
3536 // its type changes under erasure.
3537 if (allowGenerics &&
3538 resultInfo.pkind == VAR &&
3539 v.owner.kind == TYP &&
3540 (v.flags() & STATIC) == 0 &&
3541 (site.hasTag(CLASS) || site.hasTag(TYPEVAR))) {
3542 Type s = types.asOuterSuper(site, v.owner);
3543 if (s != null &&
3544 s.isRaw() &&
3545 !types.isSameType(v.type, v.erasure(types))) {
3546 chk.warnUnchecked(tree.pos(),
3547 "unchecked.assign.to.var",
3548 v, s);
3549 }
3550 }
3551 // The computed type of a variable is the type of the
3552 // variable symbol, taken as a member of the site type.
3553 owntype = (sym.owner.kind == TYP &&
3554 sym.name != names._this && sym.name != names._super)
3555 ? types.memberType(site, sym)
3556 : sym.type;
3558 // If the variable is a constant, record constant value in
3559 // computed type.
3560 if (v.getConstValue() != null && isStaticReference(tree))
3561 owntype = owntype.constType(v.getConstValue());
3563 if (resultInfo.pkind == VAL) {
3564 owntype = capture(owntype); // capture "names as expressions"
3565 }
3566 break;
3567 case MTH: {
3568 owntype = checkMethod(site, sym,
3569 new ResultInfo(resultInfo.pkind, resultInfo.pt.getReturnType(), resultInfo.checkContext),
3570 env, TreeInfo.args(env.tree), resultInfo.pt.getParameterTypes(),
3571 resultInfo.pt.getTypeArguments());
3572 break;
3573 }
3574 case PCK: case ERR:
3575 owntype = sym.type;
3576 break;
3577 default:
3578 throw new AssertionError("unexpected kind: " + sym.kind +
3579 " in tree " + tree);
3580 }
3582 // Test (1): emit a `deprecation' warning if symbol is deprecated.
3583 // (for constructors, the error was given when the constructor was
3584 // resolved)
3586 if (sym.name != names.init) {
3587 chk.checkDeprecated(tree.pos(), env.info.scope.owner, sym);
3588 chk.checkSunAPI(tree.pos(), sym);
3589 chk.checkProfile(tree.pos(), sym);
3590 }
3592 // Test (3): if symbol is a variable, check that its type and
3593 // kind are compatible with the prototype and protokind.
3594 return check(tree, owntype, sym.kind, resultInfo);
3595 }
3597 /** Check that variable is initialized and evaluate the variable's
3598 * initializer, if not yet done. Also check that variable is not
3599 * referenced before it is defined.
3600 * @param tree The tree making up the variable reference.
3601 * @param env The current environment.
3602 * @param v The variable's symbol.
3603 */
3604 private void checkInit(JCTree tree,
3605 Env<AttrContext> env,
3606 VarSymbol v,
3607 boolean onlyWarning) {
3608 // System.err.println(v + " " + ((v.flags() & STATIC) != 0) + " " +
3609 // tree.pos + " " + v.pos + " " +
3610 // Resolve.isStatic(env));//DEBUG
3612 // A forward reference is diagnosed if the declaration position
3613 // of the variable is greater than the current tree position
3614 // and the tree and variable definition occur in the same class
3615 // definition. Note that writes don't count as references.
3616 // This check applies only to class and instance
3617 // variables. Local variables follow different scope rules,
3618 // and are subject to definite assignment checking.
3619 if ((env.info.enclVar == v || v.pos > tree.pos) &&
3620 v.owner.kind == TYP &&
3621 canOwnInitializer(owner(env)) &&
3622 v.owner == env.info.scope.owner.enclClass() &&
3623 ((v.flags() & STATIC) != 0) == Resolve.isStatic(env) &&
3624 (!env.tree.hasTag(ASSIGN) ||
3625 TreeInfo.skipParens(((JCAssign) env.tree).lhs) != tree)) {
3626 String suffix = (env.info.enclVar == v) ?
3627 "self.ref" : "forward.ref";
3628 if (!onlyWarning || isStaticEnumField(v)) {
3629 log.error(tree.pos(), "illegal." + suffix);
3630 } else if (useBeforeDeclarationWarning) {
3631 log.warning(tree.pos(), suffix, v);
3632 }
3633 }
3635 v.getConstValue(); // ensure initializer is evaluated
3637 checkEnumInitializer(tree, env, v);
3638 }
3640 /**
3641 * Check for illegal references to static members of enum. In
3642 * an enum type, constructors and initializers may not
3643 * reference its static members unless they are constant.
3644 *
3645 * @param tree The tree making up the variable reference.
3646 * @param env The current environment.
3647 * @param v The variable's symbol.
3648 * @jls section 8.9 Enums
3649 */
3650 private void checkEnumInitializer(JCTree tree, Env<AttrContext> env, VarSymbol v) {
3651 // JLS:
3652 //
3653 // "It is a compile-time error to reference a static field
3654 // of an enum type that is not a compile-time constant
3655 // (15.28) from constructors, instance initializer blocks,
3656 // or instance variable initializer expressions of that
3657 // type. It is a compile-time error for the constructors,
3658 // instance initializer blocks, or instance variable
3659 // initializer expressions of an enum constant e to refer
3660 // to itself or to an enum constant of the same type that
3661 // is declared to the right of e."
3662 if (isStaticEnumField(v)) {
3663 ClassSymbol enclClass = env.info.scope.owner.enclClass();
3665 if (enclClass == null || enclClass.owner == null)
3666 return;
3668 // See if the enclosing class is the enum (or a
3669 // subclass thereof) declaring v. If not, this
3670 // reference is OK.
3671 if (v.owner != enclClass && !types.isSubtype(enclClass.type, v.owner.type))
3672 return;
3674 // If the reference isn't from an initializer, then
3675 // the reference is OK.
3676 if (!Resolve.isInitializer(env))
3677 return;
3679 log.error(tree.pos(), "illegal.enum.static.ref");
3680 }
3681 }
3683 /** Is the given symbol a static, non-constant field of an Enum?
3684 * Note: enum literals should not be regarded as such
3685 */
3686 private boolean isStaticEnumField(VarSymbol v) {
3687 return Flags.isEnum(v.owner) &&
3688 Flags.isStatic(v) &&
3689 !Flags.isConstant(v) &&
3690 v.name != names._class;
3691 }
3693 /** Can the given symbol be the owner of code which forms part
3694 * if class initialization? This is the case if the symbol is
3695 * a type or field, or if the symbol is the synthetic method.
3696 * owning a block.
3697 */
3698 private boolean canOwnInitializer(Symbol sym) {
3699 return
3700 (sym.kind & (VAR | TYP)) != 0 ||
3701 (sym.kind == MTH && (sym.flags() & BLOCK) != 0);
3702 }
3704 Warner noteWarner = new Warner();
3706 /**
3707 * Check that method arguments conform to its instantiation.
3708 **/
3709 public Type checkMethod(Type site,
3710 final Symbol sym,
3711 ResultInfo resultInfo,
3712 Env<AttrContext> env,
3713 final List<JCExpression> argtrees,
3714 List<Type> argtypes,
3715 List<Type> typeargtypes) {
3716 // Test (5): if symbol is an instance method of a raw type, issue
3717 // an unchecked warning if its argument types change under erasure.
3718 if (allowGenerics &&
3719 (sym.flags() & STATIC) == 0 &&
3720 (site.hasTag(CLASS) || site.hasTag(TYPEVAR))) {
3721 Type s = types.asOuterSuper(site, sym.owner);
3722 if (s != null && s.isRaw() &&
3723 !types.isSameTypes(sym.type.getParameterTypes(),
3724 sym.erasure(types).getParameterTypes())) {
3725 chk.warnUnchecked(env.tree.pos(),
3726 "unchecked.call.mbr.of.raw.type",
3727 sym, s);
3728 }
3729 }
3731 if (env.info.defaultSuperCallSite != null) {
3732 for (Type sup : types.interfaces(env.enclClass.type).prepend(types.supertype((env.enclClass.type)))) {
3733 if (!sup.tsym.isSubClass(sym.enclClass(), types) ||
3734 types.isSameType(sup, env.info.defaultSuperCallSite)) continue;
3735 List<MethodSymbol> icand_sup =
3736 types.interfaceCandidates(sup, (MethodSymbol)sym);
3737 if (icand_sup.nonEmpty() &&
3738 icand_sup.head != sym &&
3739 icand_sup.head.overrides(sym, icand_sup.head.enclClass(), types, true)) {
3740 log.error(env.tree.pos(), "illegal.default.super.call", env.info.defaultSuperCallSite,
3741 diags.fragment("overridden.default", sym, sup));
3742 break;
3743 }
3744 }
3745 env.info.defaultSuperCallSite = null;
3746 }
3748 if (sym.isStatic() && site.isInterface() && env.tree.hasTag(APPLY)) {
3749 JCMethodInvocation app = (JCMethodInvocation)env.tree;
3750 if (app.meth.hasTag(SELECT) &&
3751 !TreeInfo.isStaticSelector(((JCFieldAccess)app.meth).selected, names)) {
3752 log.error(env.tree.pos(), "illegal.static.intf.meth.call", site);
3753 }
3754 }
3756 // Compute the identifier's instantiated type.
3757 // For methods, we need to compute the instance type by
3758 // Resolve.instantiate from the symbol's type as well as
3759 // any type arguments and value arguments.
3760 noteWarner.clear();
3761 try {
3762 Type owntype = rs.checkMethod(
3763 env,
3764 site,
3765 sym,
3766 resultInfo,
3767 argtypes,
3768 typeargtypes,
3769 noteWarner);
3771 DeferredAttr.DeferredTypeMap checkDeferredMap =
3772 deferredAttr.new DeferredTypeMap(DeferredAttr.AttrMode.CHECK, sym, env.info.pendingResolutionPhase);
3774 argtypes = Type.map(argtypes, checkDeferredMap);
3776 if (noteWarner.hasNonSilentLint(LintCategory.UNCHECKED)) {
3777 chk.warnUnchecked(env.tree.pos(),
3778 "unchecked.meth.invocation.applied",
3779 kindName(sym),
3780 sym.name,
3781 rs.methodArguments(sym.type.getParameterTypes()),
3782 rs.methodArguments(Type.map(argtypes, checkDeferredMap)),
3783 kindName(sym.location()),
3784 sym.location());
3785 owntype = new MethodType(owntype.getParameterTypes(),
3786 types.erasure(owntype.getReturnType()),
3787 types.erasure(owntype.getThrownTypes()),
3788 syms.methodClass);
3789 }
3791 return chk.checkMethod(owntype, sym, env, argtrees, argtypes, env.info.lastResolveVarargs(),
3792 resultInfo.checkContext.inferenceContext());
3793 } catch (Infer.InferenceException ex) {
3794 //invalid target type - propagate exception outwards or report error
3795 //depending on the current check context
3796 resultInfo.checkContext.report(env.tree.pos(), ex.getDiagnostic());
3797 return types.createErrorType(site);
3798 } catch (Resolve.InapplicableMethodException ex) {
3799 final JCDiagnostic diag = ex.getDiagnostic();
3800 Resolve.InapplicableSymbolError errSym = rs.new InapplicableSymbolError(null) {
3801 @Override
3802 protected Pair<Symbol, JCDiagnostic> errCandidate() {
3803 return new Pair<Symbol, JCDiagnostic>(sym, diag);
3804 }
3805 };
3806 List<Type> argtypes2 = Type.map(argtypes,
3807 rs.new ResolveDeferredRecoveryMap(AttrMode.CHECK, sym, env.info.pendingResolutionPhase));
3808 JCDiagnostic errDiag = errSym.getDiagnostic(JCDiagnostic.DiagnosticType.ERROR,
3809 env.tree, sym, site, sym.name, argtypes2, typeargtypes);
3810 log.report(errDiag);
3811 return types.createErrorType(site);
3812 }
3813 }
3815 public void visitLiteral(JCLiteral tree) {
3816 result = check(
3817 tree, litType(tree.typetag).constType(tree.value), VAL, resultInfo);
3818 }
3819 //where
3820 /** Return the type of a literal with given type tag.
3821 */
3822 Type litType(TypeTag tag) {
3823 return (tag == CLASS) ? syms.stringType : syms.typeOfTag[tag.ordinal()];
3824 }
3826 public void visitTypeIdent(JCPrimitiveTypeTree tree) {
3827 result = check(tree, syms.typeOfTag[tree.typetag.ordinal()], TYP, resultInfo);
3828 }
3830 public void visitTypeArray(JCArrayTypeTree tree) {
3831 Type etype = attribType(tree.elemtype, env);
3832 Type type = new ArrayType(etype, syms.arrayClass);
3833 result = check(tree, type, TYP, resultInfo);
3834 }
3836 /** Visitor method for parameterized types.
3837 * Bound checking is left until later, since types are attributed
3838 * before supertype structure is completely known
3839 */
3840 public void visitTypeApply(JCTypeApply tree) {
3841 Type owntype = types.createErrorType(tree.type);
3843 // Attribute functor part of application and make sure it's a class.
3844 Type clazztype = chk.checkClassType(tree.clazz.pos(), attribType(tree.clazz, env));
3846 // Attribute type parameters
3847 List<Type> actuals = attribTypes(tree.arguments, env);
3849 if (clazztype.hasTag(CLASS)) {
3850 List<Type> formals = clazztype.tsym.type.getTypeArguments();
3851 if (actuals.isEmpty()) //diamond
3852 actuals = formals;
3854 if (actuals.length() == formals.length()) {
3855 List<Type> a = actuals;
3856 List<Type> f = formals;
3857 while (a.nonEmpty()) {
3858 a.head = a.head.withTypeVar(f.head);
3859 a = a.tail;
3860 f = f.tail;
3861 }
3862 // Compute the proper generic outer
3863 Type clazzOuter = clazztype.getEnclosingType();
3864 if (clazzOuter.hasTag(CLASS)) {
3865 Type site;
3866 JCExpression clazz = TreeInfo.typeIn(tree.clazz);
3867 if (clazz.hasTag(IDENT)) {
3868 site = env.enclClass.sym.type;
3869 } else if (clazz.hasTag(SELECT)) {
3870 site = ((JCFieldAccess) clazz).selected.type;
3871 } else throw new AssertionError(""+tree);
3872 if (clazzOuter.hasTag(CLASS) && site != clazzOuter) {
3873 if (site.hasTag(CLASS))
3874 site = types.asOuterSuper(site, clazzOuter.tsym);
3875 if (site == null)
3876 site = types.erasure(clazzOuter);
3877 clazzOuter = site;
3878 }
3879 }
3880 owntype = new ClassType(clazzOuter, actuals, clazztype.tsym);
3881 if (clazztype.isAnnotated()) {
3882 // Use the same AnnotatedType, because it will have
3883 // its annotations set later.
3884 ((AnnotatedType)clazztype).underlyingType = owntype;
3885 owntype = clazztype;
3886 }
3887 } else {
3888 if (formals.length() != 0) {
3889 log.error(tree.pos(), "wrong.number.type.args",
3890 Integer.toString(formals.length()));
3891 } else {
3892 log.error(tree.pos(), "type.doesnt.take.params", clazztype.tsym);
3893 }
3894 owntype = types.createErrorType(tree.type);
3895 }
3896 }
3897 result = check(tree, owntype, TYP, resultInfo);
3898 }
3900 public void visitTypeUnion(JCTypeUnion tree) {
3901 ListBuffer<Type> multicatchTypes = ListBuffer.lb();
3902 ListBuffer<Type> all_multicatchTypes = null; // lazy, only if needed
3903 for (JCExpression typeTree : tree.alternatives) {
3904 Type ctype = attribType(typeTree, env);
3905 ctype = chk.checkType(typeTree.pos(),
3906 chk.checkClassType(typeTree.pos(), ctype),
3907 syms.throwableType);
3908 if (!ctype.isErroneous()) {
3909 //check that alternatives of a union type are pairwise
3910 //unrelated w.r.t. subtyping
3911 if (chk.intersects(ctype, multicatchTypes.toList())) {
3912 for (Type t : multicatchTypes) {
3913 boolean sub = types.isSubtype(ctype, t);
3914 boolean sup = types.isSubtype(t, ctype);
3915 if (sub || sup) {
3916 //assume 'a' <: 'b'
3917 Type a = sub ? ctype : t;
3918 Type b = sub ? t : ctype;
3919 log.error(typeTree.pos(), "multicatch.types.must.be.disjoint", a, b);
3920 }
3921 }
3922 }
3923 multicatchTypes.append(ctype);
3924 if (all_multicatchTypes != null)
3925 all_multicatchTypes.append(ctype);
3926 } else {
3927 if (all_multicatchTypes == null) {
3928 all_multicatchTypes = ListBuffer.lb();
3929 all_multicatchTypes.appendList(multicatchTypes);
3930 }
3931 all_multicatchTypes.append(ctype);
3932 }
3933 }
3934 Type t = check(tree, types.lub(multicatchTypes.toList()), TYP, resultInfo);
3935 if (t.hasTag(CLASS)) {
3936 List<Type> alternatives =
3937 ((all_multicatchTypes == null) ? multicatchTypes : all_multicatchTypes).toList();
3938 t = new UnionClassType((ClassType) t, alternatives);
3939 }
3940 tree.type = result = t;
3941 }
3943 public void visitTypeIntersection(JCTypeIntersection tree) {
3944 attribTypes(tree.bounds, env);
3945 tree.type = result = checkIntersection(tree, tree.bounds);
3946 }
3948 public void visitTypeParameter(JCTypeParameter tree) {
3949 TypeVar typeVar = (TypeVar) tree.type;
3951 if (tree.annotations != null && tree.annotations.nonEmpty()) {
3952 AnnotatedType antype = new AnnotatedType(typeVar);
3953 annotateType(antype, tree.annotations);
3954 tree.type = antype;
3955 }
3957 if (!typeVar.bound.isErroneous()) {
3958 //fixup type-parameter bound computed in 'attribTypeVariables'
3959 typeVar.bound = checkIntersection(tree, tree.bounds);
3960 }
3961 }
3963 Type checkIntersection(JCTree tree, List<JCExpression> bounds) {
3964 Set<Type> boundSet = new HashSet<Type>();
3965 if (bounds.nonEmpty()) {
3966 // accept class or interface or typevar as first bound.
3967 bounds.head.type = checkBase(bounds.head.type, bounds.head, env, false, false, false);
3968 boundSet.add(types.erasure(bounds.head.type));
3969 if (bounds.head.type.isErroneous()) {
3970 return bounds.head.type;
3971 }
3972 else if (bounds.head.type.hasTag(TYPEVAR)) {
3973 // if first bound was a typevar, do not accept further bounds.
3974 if (bounds.tail.nonEmpty()) {
3975 log.error(bounds.tail.head.pos(),
3976 "type.var.may.not.be.followed.by.other.bounds");
3977 return bounds.head.type;
3978 }
3979 } else {
3980 // if first bound was a class or interface, accept only interfaces
3981 // as further bounds.
3982 for (JCExpression bound : bounds.tail) {
3983 bound.type = checkBase(bound.type, bound, env, false, true, false);
3984 if (bound.type.isErroneous()) {
3985 bounds = List.of(bound);
3986 }
3987 else if (bound.type.hasTag(CLASS)) {
3988 chk.checkNotRepeated(bound.pos(), types.erasure(bound.type), boundSet);
3989 }
3990 }
3991 }
3992 }
3994 if (bounds.length() == 0) {
3995 return syms.objectType;
3996 } else if (bounds.length() == 1) {
3997 return bounds.head.type;
3998 } else {
3999 Type owntype = types.makeCompoundType(TreeInfo.types(bounds));
4000 if (tree.hasTag(TYPEINTERSECTION)) {
4001 ((IntersectionClassType)owntype).intersectionKind =
4002 IntersectionClassType.IntersectionKind.EXPLICIT;
4003 }
4004 // ... the variable's bound is a class type flagged COMPOUND
4005 // (see comment for TypeVar.bound).
4006 // In this case, generate a class tree that represents the
4007 // bound class, ...
4008 JCExpression extending;
4009 List<JCExpression> implementing;
4010 if (!bounds.head.type.isInterface()) {
4011 extending = bounds.head;
4012 implementing = bounds.tail;
4013 } else {
4014 extending = null;
4015 implementing = bounds;
4016 }
4017 JCClassDecl cd = make.at(tree).ClassDef(
4018 make.Modifiers(PUBLIC | ABSTRACT),
4019 names.empty, List.<JCTypeParameter>nil(),
4020 extending, implementing, List.<JCTree>nil());
4022 ClassSymbol c = (ClassSymbol)owntype.tsym;
4023 Assert.check((c.flags() & COMPOUND) != 0);
4024 cd.sym = c;
4025 c.sourcefile = env.toplevel.sourcefile;
4027 // ... and attribute the bound class
4028 c.flags_field |= UNATTRIBUTED;
4029 Env<AttrContext> cenv = enter.classEnv(cd, env);
4030 enter.typeEnvs.put(c, cenv);
4031 attribClass(c);
4032 return owntype;
4033 }
4034 }
4036 public void visitWildcard(JCWildcard tree) {
4037 //- System.err.println("visitWildcard("+tree+");");//DEBUG
4038 Type type = (tree.kind.kind == BoundKind.UNBOUND)
4039 ? syms.objectType
4040 : attribType(tree.inner, env);
4041 result = check(tree, new WildcardType(chk.checkRefType(tree.pos(), type),
4042 tree.kind.kind,
4043 syms.boundClass),
4044 TYP, resultInfo);
4045 }
4047 public void visitAnnotation(JCAnnotation tree) {
4048 log.error(tree.pos(), "annotation.not.valid.for.type", pt());
4049 result = tree.type = syms.errType;
4050 }
4052 public void visitAnnotatedType(JCAnnotatedType tree) {
4053 Type underlyingType = attribType(tree.getUnderlyingType(), env);
4054 this.attribAnnotationTypes(tree.annotations, env);
4055 AnnotatedType antype = new AnnotatedType(underlyingType);
4056 annotateType(antype, tree.annotations);
4057 result = tree.type = antype;
4058 }
4060 /**
4061 * Apply the annotations to the particular type.
4062 */
4063 public void annotateType(final AnnotatedType type, final List<JCAnnotation> annotations) {
4064 if (annotations.isEmpty())
4065 return;
4066 annotate.typeAnnotation(new Annotate.Annotator() {
4067 @Override
4068 public String toString() {
4069 return "annotate " + annotations + " onto " + type;
4070 }
4071 @Override
4072 public void enterAnnotation() {
4073 List<Attribute.TypeCompound> compounds = fromAnnotations(annotations);
4074 type.typeAnnotations = compounds;
4075 }
4076 });
4077 }
4079 private static List<Attribute.TypeCompound> fromAnnotations(List<JCAnnotation> annotations) {
4080 if (annotations.isEmpty())
4081 return List.nil();
4083 ListBuffer<Attribute.TypeCompound> buf = ListBuffer.lb();
4084 for (JCAnnotation anno : annotations) {
4085 if (anno.attribute != null) {
4086 // TODO: this null-check is only needed for an obscure
4087 // ordering issue, where annotate.flush is called when
4088 // the attribute is not set yet. For an example failure
4089 // try the referenceinfos/NestedTypes.java test.
4090 // Any better solutions?
4091 buf.append((Attribute.TypeCompound) anno.attribute);
4092 }
4093 }
4094 return buf.toList();
4095 }
4097 public void visitErroneous(JCErroneous tree) {
4098 if (tree.errs != null)
4099 for (JCTree err : tree.errs)
4100 attribTree(err, env, new ResultInfo(ERR, pt()));
4101 result = tree.type = syms.errType;
4102 }
4104 /** Default visitor method for all other trees.
4105 */
4106 public void visitTree(JCTree tree) {
4107 throw new AssertionError();
4108 }
4110 /**
4111 * Attribute an env for either a top level tree or class declaration.
4112 */
4113 public void attrib(Env<AttrContext> env) {
4114 if (env.tree.hasTag(TOPLEVEL))
4115 attribTopLevel(env);
4116 else
4117 attribClass(env.tree.pos(), env.enclClass.sym);
4118 }
4120 /**
4121 * Attribute a top level tree. These trees are encountered when the
4122 * package declaration has annotations.
4123 */
4124 public void attribTopLevel(Env<AttrContext> env) {
4125 JCCompilationUnit toplevel = env.toplevel;
4126 try {
4127 annotate.flush();
4128 chk.validateAnnotations(toplevel.packageAnnotations, toplevel.packge);
4129 } catch (CompletionFailure ex) {
4130 chk.completionError(toplevel.pos(), ex);
4131 }
4132 }
4134 /** Main method: attribute class definition associated with given class symbol.
4135 * reporting completion failures at the given position.
4136 * @param pos The source position at which completion errors are to be
4137 * reported.
4138 * @param c The class symbol whose definition will be attributed.
4139 */
4140 public void attribClass(DiagnosticPosition pos, ClassSymbol c) {
4141 try {
4142 annotate.flush();
4143 attribClass(c);
4144 } catch (CompletionFailure ex) {
4145 chk.completionError(pos, ex);
4146 }
4147 }
4149 /** Attribute class definition associated with given class symbol.
4150 * @param c The class symbol whose definition will be attributed.
4151 */
4152 void attribClass(ClassSymbol c) throws CompletionFailure {
4153 if (c.type.hasTag(ERROR)) return;
4155 // Check for cycles in the inheritance graph, which can arise from
4156 // ill-formed class files.
4157 chk.checkNonCyclic(null, c.type);
4159 Type st = types.supertype(c.type);
4160 if ((c.flags_field & Flags.COMPOUND) == 0) {
4161 // First, attribute superclass.
4162 if (st.hasTag(CLASS))
4163 attribClass((ClassSymbol)st.tsym);
4165 // Next attribute owner, if it is a class.
4166 if (c.owner.kind == TYP && c.owner.type.hasTag(CLASS))
4167 attribClass((ClassSymbol)c.owner);
4168 }
4170 // The previous operations might have attributed the current class
4171 // if there was a cycle. So we test first whether the class is still
4172 // UNATTRIBUTED.
4173 if ((c.flags_field & UNATTRIBUTED) != 0) {
4174 c.flags_field &= ~UNATTRIBUTED;
4176 // Get environment current at the point of class definition.
4177 Env<AttrContext> env = enter.typeEnvs.get(c);
4179 // The info.lint field in the envs stored in enter.typeEnvs is deliberately uninitialized,
4180 // because the annotations were not available at the time the env was created. Therefore,
4181 // we look up the environment chain for the first enclosing environment for which the
4182 // lint value is set. Typically, this is the parent env, but might be further if there
4183 // are any envs created as a result of TypeParameter nodes.
4184 Env<AttrContext> lintEnv = env;
4185 while (lintEnv.info.lint == null)
4186 lintEnv = lintEnv.next;
4188 // Having found the enclosing lint value, we can initialize the lint value for this class
4189 env.info.lint = lintEnv.info.lint.augment(c);
4191 Lint prevLint = chk.setLint(env.info.lint);
4192 JavaFileObject prev = log.useSource(c.sourcefile);
4193 ResultInfo prevReturnRes = env.info.returnResult;
4195 try {
4196 env.info.returnResult = null;
4197 // java.lang.Enum may not be subclassed by a non-enum
4198 if (st.tsym == syms.enumSym &&
4199 ((c.flags_field & (Flags.ENUM|Flags.COMPOUND)) == 0))
4200 log.error(env.tree.pos(), "enum.no.subclassing");
4202 // Enums may not be extended by source-level classes
4203 if (st.tsym != null &&
4204 ((st.tsym.flags_field & Flags.ENUM) != 0) &&
4205 ((c.flags_field & (Flags.ENUM | Flags.COMPOUND)) == 0)) {
4206 log.error(env.tree.pos(), "enum.types.not.extensible");
4207 }
4208 attribClassBody(env, c);
4210 chk.checkDeprecatedAnnotation(env.tree.pos(), c);
4211 chk.checkClassOverrideEqualsAndHashIfNeeded(env.tree.pos(), c);
4212 } finally {
4213 env.info.returnResult = prevReturnRes;
4214 log.useSource(prev);
4215 chk.setLint(prevLint);
4216 }
4218 }
4219 }
4221 public void visitImport(JCImport tree) {
4222 // nothing to do
4223 }
4225 /** Finish the attribution of a class. */
4226 private void attribClassBody(Env<AttrContext> env, ClassSymbol c) {
4227 JCClassDecl tree = (JCClassDecl)env.tree;
4228 Assert.check(c == tree.sym);
4230 // Validate annotations
4231 chk.validateAnnotations(tree.mods.annotations, c);
4233 // Validate type parameters, supertype and interfaces.
4234 attribStats(tree.typarams, env);
4235 if (!c.isAnonymous()) {
4236 //already checked if anonymous
4237 chk.validate(tree.typarams, env);
4238 chk.validate(tree.extending, env);
4239 chk.validate(tree.implementing, env);
4240 }
4242 // If this is a non-abstract class, check that it has no abstract
4243 // methods or unimplemented methods of an implemented interface.
4244 if ((c.flags() & (ABSTRACT | INTERFACE)) == 0) {
4245 if (!relax)
4246 chk.checkAllDefined(tree.pos(), c);
4247 }
4249 if ((c.flags() & ANNOTATION) != 0) {
4250 if (tree.implementing.nonEmpty())
4251 log.error(tree.implementing.head.pos(),
4252 "cant.extend.intf.annotation");
4253 if (tree.typarams.nonEmpty())
4254 log.error(tree.typarams.head.pos(),
4255 "intf.annotation.cant.have.type.params");
4257 // If this annotation has a @Repeatable, validate
4258 Attribute.Compound repeatable = c.attribute(syms.repeatableType.tsym);
4259 if (repeatable != null) {
4260 // get diagnostic position for error reporting
4261 DiagnosticPosition cbPos = getDiagnosticPosition(tree, repeatable.type);
4262 Assert.checkNonNull(cbPos);
4264 chk.validateRepeatable(c, repeatable, cbPos);
4265 }
4266 } else {
4267 // Check that all extended classes and interfaces
4268 // are compatible (i.e. no two define methods with same arguments
4269 // yet different return types). (JLS 8.4.6.3)
4270 chk.checkCompatibleSupertypes(tree.pos(), c.type);
4271 if (allowDefaultMethods) {
4272 chk.checkDefaultMethodClashes(tree.pos(), c.type);
4273 }
4274 }
4276 // Check that class does not import the same parameterized interface
4277 // with two different argument lists.
4278 chk.checkClassBounds(tree.pos(), c.type);
4280 tree.type = c.type;
4282 for (List<JCTypeParameter> l = tree.typarams;
4283 l.nonEmpty(); l = l.tail) {
4284 Assert.checkNonNull(env.info.scope.lookup(l.head.name).scope);
4285 }
4287 // Check that a generic class doesn't extend Throwable
4288 if (!c.type.allparams().isEmpty() && types.isSubtype(c.type, syms.throwableType))
4289 log.error(tree.extending.pos(), "generic.throwable");
4291 // Check that all methods which implement some
4292 // method conform to the method they implement.
4293 chk.checkImplementations(tree);
4295 //check that a resource implementing AutoCloseable cannot throw InterruptedException
4296 checkAutoCloseable(tree.pos(), env, c.type);
4298 for (List<JCTree> l = tree.defs; l.nonEmpty(); l = l.tail) {
4299 // Attribute declaration
4300 attribStat(l.head, env);
4301 // Check that declarations in inner classes are not static (JLS 8.1.2)
4302 // Make an exception for static constants.
4303 if (c.owner.kind != PCK &&
4304 ((c.flags() & STATIC) == 0 || c.name == names.empty) &&
4305 (TreeInfo.flags(l.head) & (STATIC | INTERFACE)) != 0) {
4306 Symbol sym = null;
4307 if (l.head.hasTag(VARDEF)) sym = ((JCVariableDecl) l.head).sym;
4308 if (sym == null ||
4309 sym.kind != VAR ||
4310 ((VarSymbol) sym).getConstValue() == null)
4311 log.error(l.head.pos(), "icls.cant.have.static.decl", c);
4312 }
4313 }
4315 // Check for cycles among non-initial constructors.
4316 chk.checkCyclicConstructors(tree);
4318 // Check for cycles among annotation elements.
4319 chk.checkNonCyclicElements(tree);
4321 // Check for proper use of serialVersionUID
4322 if (env.info.lint.isEnabled(LintCategory.SERIAL) &&
4323 isSerializable(c) &&
4324 (c.flags() & Flags.ENUM) == 0 &&
4325 checkForSerial(c)) {
4326 checkSerialVersionUID(tree, c);
4327 }
4328 if (allowTypeAnnos) {
4329 // Correctly organize the postions of the type annotations
4330 TypeAnnotations.organizeTypeAnnotationsBodies(this.syms, this.names, this.log, tree);
4332 // Check type annotations applicability rules
4333 validateTypeAnnotations(tree);
4334 }
4335 }
4336 // where
4337 boolean checkForSerial(ClassSymbol c) {
4338 if ((c.flags() & ABSTRACT) == 0) {
4339 return true;
4340 } else {
4341 return c.members().anyMatch(anyNonAbstractOrDefaultMethod);
4342 }
4343 }
4345 public static final Filter<Symbol> anyNonAbstractOrDefaultMethod = new Filter<Symbol>() {
4346 @Override
4347 public boolean accepts(Symbol s) {
4348 return s.kind == Kinds.MTH &&
4349 (s.flags() & (DEFAULT | ABSTRACT)) != ABSTRACT;
4350 }
4351 };
4353 /** get a diagnostic position for an attribute of Type t, or null if attribute missing */
4354 private DiagnosticPosition getDiagnosticPosition(JCClassDecl tree, Type t) {
4355 for(List<JCAnnotation> al = tree.mods.annotations; !al.isEmpty(); al = al.tail) {
4356 if (types.isSameType(al.head.annotationType.type, t))
4357 return al.head.pos();
4358 }
4360 return null;
4361 }
4363 /** check if a class is a subtype of Serializable, if that is available. */
4364 private boolean isSerializable(ClassSymbol c) {
4365 try {
4366 syms.serializableType.complete();
4367 }
4368 catch (CompletionFailure e) {
4369 return false;
4370 }
4371 return types.isSubtype(c.type, syms.serializableType);
4372 }
4374 /** Check that an appropriate serialVersionUID member is defined. */
4375 private void checkSerialVersionUID(JCClassDecl tree, ClassSymbol c) {
4377 // check for presence of serialVersionUID
4378 Scope.Entry e = c.members().lookup(names.serialVersionUID);
4379 while (e.scope != null && e.sym.kind != VAR) e = e.next();
4380 if (e.scope == null) {
4381 log.warning(LintCategory.SERIAL,
4382 tree.pos(), "missing.SVUID", c);
4383 return;
4384 }
4386 // check that it is static final
4387 VarSymbol svuid = (VarSymbol)e.sym;
4388 if ((svuid.flags() & (STATIC | FINAL)) !=
4389 (STATIC | FINAL))
4390 log.warning(LintCategory.SERIAL,
4391 TreeInfo.diagnosticPositionFor(svuid, tree), "improper.SVUID", c);
4393 // check that it is long
4394 else if (!svuid.type.hasTag(LONG))
4395 log.warning(LintCategory.SERIAL,
4396 TreeInfo.diagnosticPositionFor(svuid, tree), "long.SVUID", c);
4398 // check constant
4399 else if (svuid.getConstValue() == null)
4400 log.warning(LintCategory.SERIAL,
4401 TreeInfo.diagnosticPositionFor(svuid, tree), "constant.SVUID", c);
4402 }
4404 private Type capture(Type type) {
4405 return types.capture(type);
4406 }
4408 private void validateTypeAnnotations(JCTree tree) {
4409 tree.accept(typeAnnotationsValidator);
4410 }
4411 //where
4412 private final JCTree.Visitor typeAnnotationsValidator = new TreeScanner() {
4414 private boolean checkAllAnnotations = false;
4416 public void visitAnnotation(JCAnnotation tree) {
4417 if (tree.hasTag(TYPE_ANNOTATION) || checkAllAnnotations) {
4418 chk.validateTypeAnnotation(tree, false);
4419 }
4420 super.visitAnnotation(tree);
4421 }
4422 public void visitTypeParameter(JCTypeParameter tree) {
4423 chk.validateTypeAnnotations(tree.annotations, true);
4424 scan(tree.bounds);
4425 // Don't call super.
4426 // This is needed because above we call validateTypeAnnotation with
4427 // false, which would forbid annotations on type parameters.
4428 // super.visitTypeParameter(tree);
4429 }
4430 public void visitMethodDef(JCMethodDecl tree) {
4431 if (tree.recvparam != null &&
4432 tree.recvparam.vartype.type.getKind() != TypeKind.ERROR) {
4433 checkForDeclarationAnnotations(tree.recvparam.mods.annotations,
4434 tree.recvparam.vartype.type.tsym);
4435 }
4436 if (tree.restype != null && tree.restype.type != null) {
4437 validateAnnotatedType(tree.restype, tree.restype.type);
4438 }
4439 super.visitMethodDef(tree);
4440 }
4441 public void visitVarDef(final JCVariableDecl tree) {
4442 if (tree.sym != null && tree.sym.type != null)
4443 validateAnnotatedType(tree, tree.sym.type);
4444 super.visitVarDef(tree);
4445 }
4446 public void visitTypeCast(JCTypeCast tree) {
4447 if (tree.clazz != null && tree.clazz.type != null)
4448 validateAnnotatedType(tree.clazz, tree.clazz.type);
4449 super.visitTypeCast(tree);
4450 }
4451 public void visitTypeTest(JCInstanceOf tree) {
4452 if (tree.clazz != null && tree.clazz.type != null)
4453 validateAnnotatedType(tree.clazz, tree.clazz.type);
4454 super.visitTypeTest(tree);
4455 }
4456 public void visitNewClass(JCNewClass tree) {
4457 if (tree.clazz.hasTag(ANNOTATED_TYPE)) {
4458 boolean prevCheck = this.checkAllAnnotations;
4459 try {
4460 this.checkAllAnnotations = true;
4461 scan(((JCAnnotatedType)tree.clazz).annotations);
4462 } finally {
4463 this.checkAllAnnotations = prevCheck;
4464 }
4465 }
4466 super.visitNewClass(tree);
4467 }
4468 public void visitNewArray(JCNewArray tree) {
4469 if (tree.elemtype != null && tree.elemtype.hasTag(ANNOTATED_TYPE)) {
4470 boolean prevCheck = this.checkAllAnnotations;
4471 try {
4472 this.checkAllAnnotations = true;
4473 scan(((JCAnnotatedType)tree.elemtype).annotations);
4474 } finally {
4475 this.checkAllAnnotations = prevCheck;
4476 }
4477 }
4478 super.visitNewArray(tree);
4479 }
4481 /* I would want to model this after
4482 * com.sun.tools.javac.comp.Check.Validator.visitSelectInternal(JCFieldAccess)
4483 * and override visitSelect and visitTypeApply.
4484 * However, we only set the annotated type in the top-level type
4485 * of the symbol.
4486 * Therefore, we need to override each individual location where a type
4487 * can occur.
4488 */
4489 private void validateAnnotatedType(final JCTree errtree, final Type type) {
4490 if (type.getEnclosingType() != null &&
4491 type != type.getEnclosingType()) {
4492 validateEnclosingAnnotatedType(errtree, type.getEnclosingType());
4493 }
4494 for (Type targ : type.getTypeArguments()) {
4495 validateAnnotatedType(errtree, targ);
4496 }
4497 }
4498 private void validateEnclosingAnnotatedType(final JCTree errtree, final Type type) {
4499 validateAnnotatedType(errtree, type);
4500 if (type.tsym != null &&
4501 type.tsym.isStatic() &&
4502 type.getAnnotationMirrors().nonEmpty()) {
4503 // Enclosing static classes cannot have type annotations.
4504 log.error(errtree.pos(), "cant.annotate.static.class");
4505 }
4506 }
4507 };
4509 // <editor-fold desc="post-attribution visitor">
4511 /**
4512 * Handle missing types/symbols in an AST. This routine is useful when
4513 * the compiler has encountered some errors (which might have ended up
4514 * terminating attribution abruptly); if the compiler is used in fail-over
4515 * mode (e.g. by an IDE) and the AST contains semantic errors, this routine
4516 * prevents NPE to be progagated during subsequent compilation steps.
4517 */
4518 public void postAttr(JCTree tree) {
4519 new PostAttrAnalyzer().scan(tree);
4520 }
4522 class PostAttrAnalyzer extends TreeScanner {
4524 private void initTypeIfNeeded(JCTree that) {
4525 if (that.type == null) {
4526 that.type = syms.unknownType;
4527 }
4528 }
4530 @Override
4531 public void scan(JCTree tree) {
4532 if (tree == null) return;
4533 if (tree instanceof JCExpression) {
4534 initTypeIfNeeded(tree);
4535 }
4536 super.scan(tree);
4537 }
4539 @Override
4540 public void visitIdent(JCIdent that) {
4541 if (that.sym == null) {
4542 that.sym = syms.unknownSymbol;
4543 }
4544 }
4546 @Override
4547 public void visitSelect(JCFieldAccess that) {
4548 if (that.sym == null) {
4549 that.sym = syms.unknownSymbol;
4550 }
4551 super.visitSelect(that);
4552 }
4554 @Override
4555 public void visitClassDef(JCClassDecl that) {
4556 initTypeIfNeeded(that);
4557 if (that.sym == null) {
4558 that.sym = new ClassSymbol(0, that.name, that.type, syms.noSymbol);
4559 }
4560 super.visitClassDef(that);
4561 }
4563 @Override
4564 public void visitMethodDef(JCMethodDecl that) {
4565 initTypeIfNeeded(that);
4566 if (that.sym == null) {
4567 that.sym = new MethodSymbol(0, that.name, that.type, syms.noSymbol);
4568 }
4569 super.visitMethodDef(that);
4570 }
4572 @Override
4573 public void visitVarDef(JCVariableDecl that) {
4574 initTypeIfNeeded(that);
4575 if (that.sym == null) {
4576 that.sym = new VarSymbol(0, that.name, that.type, syms.noSymbol);
4577 that.sym.adr = 0;
4578 }
4579 super.visitVarDef(that);
4580 }
4582 @Override
4583 public void visitNewClass(JCNewClass that) {
4584 if (that.constructor == null) {
4585 that.constructor = new MethodSymbol(0, names.init, syms.unknownType, syms.noSymbol);
4586 }
4587 if (that.constructorType == null) {
4588 that.constructorType = syms.unknownType;
4589 }
4590 super.visitNewClass(that);
4591 }
4593 @Override
4594 public void visitAssignop(JCAssignOp that) {
4595 if (that.operator == null)
4596 that.operator = new OperatorSymbol(names.empty, syms.unknownType, -1, syms.noSymbol);
4597 super.visitAssignop(that);
4598 }
4600 @Override
4601 public void visitBinary(JCBinary that) {
4602 if (that.operator == null)
4603 that.operator = new OperatorSymbol(names.empty, syms.unknownType, -1, syms.noSymbol);
4604 super.visitBinary(that);
4605 }
4607 @Override
4608 public void visitUnary(JCUnary that) {
4609 if (that.operator == null)
4610 that.operator = new OperatorSymbol(names.empty, syms.unknownType, -1, syms.noSymbol);
4611 super.visitUnary(that);
4612 }
4614 @Override
4615 public void visitLambda(JCLambda that) {
4616 super.visitLambda(that);
4617 if (that.targets == null) {
4618 that.targets = List.nil();
4619 }
4620 }
4622 @Override
4623 public void visitReference(JCMemberReference that) {
4624 super.visitReference(that);
4625 if (that.sym == null) {
4626 that.sym = new MethodSymbol(0, names.empty, syms.unknownType, syms.noSymbol);
4627 }
4628 if (that.targets == null) {
4629 that.targets = List.nil();
4630 }
4631 }
4632 }
4633 // </editor-fold>
4634 }