Mon, 07 Mar 2011 14:31:50 +0000
7020044: Project Coin: diamond erroneous allowed on some anonymous inner classes
Summary: Disallow diamond on anonymous innner class creation expression (as per JSR 334's EDR)
Reviewed-by: jjg
1 /*
2 * Copyright (c) 1999, 2011, Oracle and/or its affiliates. All rights reserved.
3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
4 *
5 * This code is free software; you can redistribute it and/or modify it
6 * under the terms of the GNU General Public License version 2 only, as
7 * published by the Free Software Foundation. Oracle designates this
8 * particular file as subject to the "Classpath" exception as provided
9 * by Oracle in the LICENSE file that accompanied this code.
10 *
11 * This code is distributed in the hope that it will be useful, but WITHOUT
12 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
13 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
14 * version 2 for more details (a copy is included in the LICENSE file that
15 * accompanied this code).
16 *
17 * You should have received a copy of the GNU General Public License version
18 * 2 along with this work; if not, write to the Free Software Foundation,
19 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
20 *
21 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
22 * or visit www.oracle.com if you need additional information or have any
23 * questions.
24 */
26 package com.sun.tools.javac.comp;
28 import java.util.*;
29 import java.util.Set;
30 import javax.lang.model.element.ElementKind;
31 import javax.tools.JavaFileObject;
33 import com.sun.tools.javac.code.*;
34 import com.sun.tools.javac.jvm.*;
35 import com.sun.tools.javac.tree.*;
36 import com.sun.tools.javac.util.*;
37 import com.sun.tools.javac.util.JCDiagnostic.DiagnosticPosition;
38 import com.sun.tools.javac.util.List;
40 import com.sun.tools.javac.jvm.Target;
41 import com.sun.tools.javac.code.Lint.LintCategory;
42 import com.sun.tools.javac.code.Symbol.*;
43 import com.sun.tools.javac.tree.JCTree.*;
44 import com.sun.tools.javac.code.Type.*;
46 import com.sun.source.tree.IdentifierTree;
47 import com.sun.source.tree.MemberSelectTree;
48 import com.sun.source.tree.TreeVisitor;
49 import com.sun.source.util.SimpleTreeVisitor;
51 import static com.sun.tools.javac.code.Flags.*;
52 import static com.sun.tools.javac.code.Kinds.*;
53 import static com.sun.tools.javac.code.TypeTags.*;
55 /** This is the main context-dependent analysis phase in GJC. It
56 * encompasses name resolution, type checking and constant folding as
57 * subtasks. Some subtasks involve auxiliary classes.
58 * @see Check
59 * @see Resolve
60 * @see ConstFold
61 * @see Infer
62 *
63 * <p><b>This is NOT part of any supported API.
64 * If you write code that depends on this, you do so at your own risk.
65 * This code and its internal interfaces are subject to change or
66 * deletion without notice.</b>
67 */
68 public class Attr extends JCTree.Visitor {
69 protected static final Context.Key<Attr> attrKey =
70 new Context.Key<Attr>();
72 final Names names;
73 final Log log;
74 final Symtab syms;
75 final Resolve rs;
76 final Infer infer;
77 final Check chk;
78 final MemberEnter memberEnter;
79 final TreeMaker make;
80 final ConstFold cfolder;
81 final Enter enter;
82 final Target target;
83 final Types types;
84 final JCDiagnostic.Factory diags;
85 final Annotate annotate;
86 final DeferredLintHandler deferredLintHandler;
88 public static Attr instance(Context context) {
89 Attr instance = context.get(attrKey);
90 if (instance == null)
91 instance = new Attr(context);
92 return instance;
93 }
95 protected Attr(Context context) {
96 context.put(attrKey, this);
98 names = Names.instance(context);
99 log = Log.instance(context);
100 syms = Symtab.instance(context);
101 rs = Resolve.instance(context);
102 chk = Check.instance(context);
103 memberEnter = MemberEnter.instance(context);
104 make = TreeMaker.instance(context);
105 enter = Enter.instance(context);
106 infer = Infer.instance(context);
107 cfolder = ConstFold.instance(context);
108 target = Target.instance(context);
109 types = Types.instance(context);
110 diags = JCDiagnostic.Factory.instance(context);
111 annotate = Annotate.instance(context);
112 deferredLintHandler = DeferredLintHandler.instance(context);
114 Options options = Options.instance(context);
116 Source source = Source.instance(context);
117 allowGenerics = source.allowGenerics();
118 allowVarargs = source.allowVarargs();
119 allowEnums = source.allowEnums();
120 allowBoxing = source.allowBoxing();
121 allowCovariantReturns = source.allowCovariantReturns();
122 allowAnonOuterThis = source.allowAnonOuterThis();
123 allowStringsInSwitch = source.allowStringsInSwitch();
124 sourceName = source.name;
125 relax = (options.isSet("-retrofit") ||
126 options.isSet("-relax"));
127 findDiamonds = options.get("findDiamond") != null &&
128 source.allowDiamond();
129 useBeforeDeclarationWarning = options.isSet("useBeforeDeclarationWarning");
130 }
132 /** Switch: relax some constraints for retrofit mode.
133 */
134 boolean relax;
136 /** Switch: support generics?
137 */
138 boolean allowGenerics;
140 /** Switch: allow variable-arity methods.
141 */
142 boolean allowVarargs;
144 /** Switch: support enums?
145 */
146 boolean allowEnums;
148 /** Switch: support boxing and unboxing?
149 */
150 boolean allowBoxing;
152 /** Switch: support covariant result types?
153 */
154 boolean allowCovariantReturns;
156 /** Switch: allow references to surrounding object from anonymous
157 * objects during constructor call?
158 */
159 boolean allowAnonOuterThis;
161 /** Switch: generates a warning if diamond can be safely applied
162 * to a given new expression
163 */
164 boolean findDiamonds;
166 /**
167 * Internally enables/disables diamond finder feature
168 */
169 static final boolean allowDiamondFinder = true;
171 /**
172 * Switch: warn about use of variable before declaration?
173 * RFE: 6425594
174 */
175 boolean useBeforeDeclarationWarning;
177 /**
178 * Switch: allow strings in switch?
179 */
180 boolean allowStringsInSwitch;
182 /**
183 * Switch: name of source level; used for error reporting.
184 */
185 String sourceName;
187 /** Check kind and type of given tree against protokind and prototype.
188 * If check succeeds, store type in tree and return it.
189 * If check fails, store errType in tree and return it.
190 * No checks are performed if the prototype is a method type.
191 * It is not necessary in this case since we know that kind and type
192 * are correct.
193 *
194 * @param tree The tree whose kind and type is checked
195 * @param owntype The computed type of the tree
196 * @param ownkind The computed kind of the tree
197 * @param pkind The expected kind (or: protokind) of the tree
198 * @param pt The expected type (or: prototype) of the tree
199 */
200 Type check(JCTree tree, Type owntype, int ownkind, int pkind, Type pt) {
201 if (owntype.tag != ERROR && pt.tag != METHOD && pt.tag != FORALL) {
202 if ((ownkind & ~pkind) == 0) {
203 owntype = chk.checkType(tree.pos(), owntype, pt, errKey);
204 } else {
205 log.error(tree.pos(), "unexpected.type",
206 kindNames(pkind),
207 kindName(ownkind));
208 owntype = types.createErrorType(owntype);
209 }
210 }
211 tree.type = owntype;
212 return owntype;
213 }
215 /** Is given blank final variable assignable, i.e. in a scope where it
216 * may be assigned to even though it is final?
217 * @param v The blank final variable.
218 * @param env The current environment.
219 */
220 boolean isAssignableAsBlankFinal(VarSymbol v, Env<AttrContext> env) {
221 Symbol owner = env.info.scope.owner;
222 // owner refers to the innermost variable, method or
223 // initializer block declaration at this point.
224 return
225 v.owner == owner
226 ||
227 ((owner.name == names.init || // i.e. we are in a constructor
228 owner.kind == VAR || // i.e. we are in a variable initializer
229 (owner.flags() & BLOCK) != 0) // i.e. we are in an initializer block
230 &&
231 v.owner == owner.owner
232 &&
233 ((v.flags() & STATIC) != 0) == Resolve.isStatic(env));
234 }
236 /** Check that variable can be assigned to.
237 * @param pos The current source code position.
238 * @param v The assigned varaible
239 * @param base If the variable is referred to in a Select, the part
240 * to the left of the `.', null otherwise.
241 * @param env The current environment.
242 */
243 void checkAssignable(DiagnosticPosition pos, VarSymbol v, JCTree base, Env<AttrContext> env) {
244 if ((v.flags() & FINAL) != 0 &&
245 ((v.flags() & HASINIT) != 0
246 ||
247 !((base == null ||
248 (base.getTag() == JCTree.IDENT && TreeInfo.name(base) == names._this)) &&
249 isAssignableAsBlankFinal(v, env)))) {
250 if (v.isResourceVariable()) { //TWR resource
251 log.error(pos, "try.resource.may.not.be.assigned", v);
252 } else {
253 log.error(pos, "cant.assign.val.to.final.var", v);
254 }
255 } else if ((v.flags() & EFFECTIVELY_FINAL) != 0) {
256 v.flags_field &= ~EFFECTIVELY_FINAL;
257 }
258 }
260 /** Does tree represent a static reference to an identifier?
261 * It is assumed that tree is either a SELECT or an IDENT.
262 * We have to weed out selects from non-type names here.
263 * @param tree The candidate tree.
264 */
265 boolean isStaticReference(JCTree tree) {
266 if (tree.getTag() == JCTree.SELECT) {
267 Symbol lsym = TreeInfo.symbol(((JCFieldAccess) tree).selected);
268 if (lsym == null || lsym.kind != TYP) {
269 return false;
270 }
271 }
272 return true;
273 }
275 /** Is this symbol a type?
276 */
277 static boolean isType(Symbol sym) {
278 return sym != null && sym.kind == TYP;
279 }
281 /** The current `this' symbol.
282 * @param env The current environment.
283 */
284 Symbol thisSym(DiagnosticPosition pos, Env<AttrContext> env) {
285 return rs.resolveSelf(pos, env, env.enclClass.sym, names._this);
286 }
288 /** Attribute a parsed identifier.
289 * @param tree Parsed identifier name
290 * @param topLevel The toplevel to use
291 */
292 public Symbol attribIdent(JCTree tree, JCCompilationUnit topLevel) {
293 Env<AttrContext> localEnv = enter.topLevelEnv(topLevel);
294 localEnv.enclClass = make.ClassDef(make.Modifiers(0),
295 syms.errSymbol.name,
296 null, null, null, null);
297 localEnv.enclClass.sym = syms.errSymbol;
298 return tree.accept(identAttributer, localEnv);
299 }
300 // where
301 private TreeVisitor<Symbol,Env<AttrContext>> identAttributer = new IdentAttributer();
302 private class IdentAttributer extends SimpleTreeVisitor<Symbol,Env<AttrContext>> {
303 @Override
304 public Symbol visitMemberSelect(MemberSelectTree node, Env<AttrContext> env) {
305 Symbol site = visit(node.getExpression(), env);
306 if (site.kind == ERR)
307 return site;
308 Name name = (Name)node.getIdentifier();
309 if (site.kind == PCK) {
310 env.toplevel.packge = (PackageSymbol)site;
311 return rs.findIdentInPackage(env, (TypeSymbol)site, name, TYP | PCK);
312 } else {
313 env.enclClass.sym = (ClassSymbol)site;
314 return rs.findMemberType(env, site.asType(), name, (TypeSymbol)site);
315 }
316 }
318 @Override
319 public Symbol visitIdentifier(IdentifierTree node, Env<AttrContext> env) {
320 return rs.findIdent(env, (Name)node.getName(), TYP | PCK);
321 }
322 }
324 public Type coerce(Type etype, Type ttype) {
325 return cfolder.coerce(etype, ttype);
326 }
328 public Type attribType(JCTree node, TypeSymbol sym) {
329 Env<AttrContext> env = enter.typeEnvs.get(sym);
330 Env<AttrContext> localEnv = env.dup(node, env.info.dup());
331 return attribTree(node, localEnv, Kinds.TYP, Type.noType);
332 }
334 public Env<AttrContext> attribExprToTree(JCTree expr, Env<AttrContext> env, JCTree tree) {
335 breakTree = tree;
336 JavaFileObject prev = log.useSource(env.toplevel.sourcefile);
337 try {
338 attribExpr(expr, env);
339 } catch (BreakAttr b) {
340 return b.env;
341 } catch (AssertionError ae) {
342 if (ae.getCause() instanceof BreakAttr) {
343 return ((BreakAttr)(ae.getCause())).env;
344 } else {
345 throw ae;
346 }
347 } finally {
348 breakTree = null;
349 log.useSource(prev);
350 }
351 return env;
352 }
354 public Env<AttrContext> attribStatToTree(JCTree stmt, Env<AttrContext> env, JCTree tree) {
355 breakTree = tree;
356 JavaFileObject prev = log.useSource(env.toplevel.sourcefile);
357 try {
358 attribStat(stmt, env);
359 } catch (BreakAttr b) {
360 return b.env;
361 } catch (AssertionError ae) {
362 if (ae.getCause() instanceof BreakAttr) {
363 return ((BreakAttr)(ae.getCause())).env;
364 } else {
365 throw ae;
366 }
367 } finally {
368 breakTree = null;
369 log.useSource(prev);
370 }
371 return env;
372 }
374 private JCTree breakTree = null;
376 private static class BreakAttr extends RuntimeException {
377 static final long serialVersionUID = -6924771130405446405L;
378 private Env<AttrContext> env;
379 private BreakAttr(Env<AttrContext> env) {
380 this.env = env;
381 }
382 }
385 /* ************************************************************************
386 * Visitor methods
387 *************************************************************************/
389 /** Visitor argument: the current environment.
390 */
391 Env<AttrContext> env;
393 /** Visitor argument: the currently expected proto-kind.
394 */
395 int pkind;
397 /** Visitor argument: the currently expected proto-type.
398 */
399 Type pt;
401 /** Visitor argument: the error key to be generated when a type error occurs
402 */
403 String errKey;
405 /** Visitor result: the computed type.
406 */
407 Type result;
409 /** Visitor method: attribute a tree, catching any completion failure
410 * exceptions. Return the tree's type.
411 *
412 * @param tree The tree to be visited.
413 * @param env The environment visitor argument.
414 * @param pkind The protokind visitor argument.
415 * @param pt The prototype visitor argument.
416 */
417 Type attribTree(JCTree tree, Env<AttrContext> env, int pkind, Type pt) {
418 return attribTree(tree, env, pkind, pt, "incompatible.types");
419 }
421 Type attribTree(JCTree tree, Env<AttrContext> env, int pkind, Type pt, String errKey) {
422 Env<AttrContext> prevEnv = this.env;
423 int prevPkind = this.pkind;
424 Type prevPt = this.pt;
425 String prevErrKey = this.errKey;
426 try {
427 this.env = env;
428 this.pkind = pkind;
429 this.pt = pt;
430 this.errKey = errKey;
431 tree.accept(this);
432 if (tree == breakTree)
433 throw new BreakAttr(env);
434 return result;
435 } catch (CompletionFailure ex) {
436 tree.type = syms.errType;
437 return chk.completionError(tree.pos(), ex);
438 } finally {
439 this.env = prevEnv;
440 this.pkind = prevPkind;
441 this.pt = prevPt;
442 this.errKey = prevErrKey;
443 }
444 }
446 /** Derived visitor method: attribute an expression tree.
447 */
448 public Type attribExpr(JCTree tree, Env<AttrContext> env, Type pt) {
449 return attribTree(tree, env, VAL, pt.tag != ERROR ? pt : Type.noType);
450 }
452 public Type attribExpr(JCTree tree, Env<AttrContext> env, Type pt, String key) {
453 return attribTree(tree, env, VAL, pt.tag != ERROR ? pt : Type.noType, key);
454 }
456 /** Derived visitor method: attribute an expression tree with
457 * no constraints on the computed type.
458 */
459 Type attribExpr(JCTree tree, Env<AttrContext> env) {
460 return attribTree(tree, env, VAL, Type.noType);
461 }
463 /** Derived visitor method: attribute a type tree.
464 */
465 Type attribType(JCTree tree, Env<AttrContext> env) {
466 Type result = attribType(tree, env, Type.noType);
467 return result;
468 }
470 /** Derived visitor method: attribute a type tree.
471 */
472 Type attribType(JCTree tree, Env<AttrContext> env, Type pt) {
473 Type result = attribTree(tree, env, TYP, pt);
474 return result;
475 }
477 /** Derived visitor method: attribute a statement or definition tree.
478 */
479 public Type attribStat(JCTree tree, Env<AttrContext> env) {
480 return attribTree(tree, env, NIL, Type.noType);
481 }
483 /** Attribute a list of expressions, returning a list of types.
484 */
485 List<Type> attribExprs(List<JCExpression> trees, Env<AttrContext> env, Type pt) {
486 ListBuffer<Type> ts = new ListBuffer<Type>();
487 for (List<JCExpression> l = trees; l.nonEmpty(); l = l.tail)
488 ts.append(attribExpr(l.head, env, pt));
489 return ts.toList();
490 }
492 /** Attribute a list of statements, returning nothing.
493 */
494 <T extends JCTree> void attribStats(List<T> trees, Env<AttrContext> env) {
495 for (List<T> l = trees; l.nonEmpty(); l = l.tail)
496 attribStat(l.head, env);
497 }
499 /** Attribute the arguments in a method call, returning a list of types.
500 */
501 List<Type> attribArgs(List<JCExpression> trees, Env<AttrContext> env) {
502 ListBuffer<Type> argtypes = new ListBuffer<Type>();
503 for (List<JCExpression> l = trees; l.nonEmpty(); l = l.tail)
504 argtypes.append(chk.checkNonVoid(
505 l.head.pos(), types.upperBound(attribTree(l.head, env, VAL, Infer.anyPoly))));
506 return argtypes.toList();
507 }
509 /** Attribute a type argument list, returning a list of types.
510 * Caller is responsible for calling checkRefTypes.
511 */
512 List<Type> attribAnyTypes(List<JCExpression> trees, Env<AttrContext> env) {
513 ListBuffer<Type> argtypes = new ListBuffer<Type>();
514 for (List<JCExpression> l = trees; l.nonEmpty(); l = l.tail)
515 argtypes.append(attribType(l.head, env));
516 return argtypes.toList();
517 }
519 /** Attribute a type argument list, returning a list of types.
520 * Check that all the types are references.
521 */
522 List<Type> attribTypes(List<JCExpression> trees, Env<AttrContext> env) {
523 List<Type> types = attribAnyTypes(trees, env);
524 return chk.checkRefTypes(trees, types);
525 }
527 /**
528 * Attribute type variables (of generic classes or methods).
529 * Compound types are attributed later in attribBounds.
530 * @param typarams the type variables to enter
531 * @param env the current environment
532 */
533 void attribTypeVariables(List<JCTypeParameter> typarams, Env<AttrContext> env) {
534 for (JCTypeParameter tvar : typarams) {
535 TypeVar a = (TypeVar)tvar.type;
536 a.tsym.flags_field |= UNATTRIBUTED;
537 a.bound = Type.noType;
538 if (!tvar.bounds.isEmpty()) {
539 List<Type> bounds = List.of(attribType(tvar.bounds.head, env));
540 for (JCExpression bound : tvar.bounds.tail)
541 bounds = bounds.prepend(attribType(bound, env));
542 types.setBounds(a, bounds.reverse());
543 } else {
544 // if no bounds are given, assume a single bound of
545 // java.lang.Object.
546 types.setBounds(a, List.of(syms.objectType));
547 }
548 a.tsym.flags_field &= ~UNATTRIBUTED;
549 }
550 for (JCTypeParameter tvar : typarams)
551 chk.checkNonCyclic(tvar.pos(), (TypeVar)tvar.type);
552 attribStats(typarams, env);
553 }
555 void attribBounds(List<JCTypeParameter> typarams) {
556 for (JCTypeParameter typaram : typarams) {
557 Type bound = typaram.type.getUpperBound();
558 if (bound != null && bound.tsym instanceof ClassSymbol) {
559 ClassSymbol c = (ClassSymbol)bound.tsym;
560 if ((c.flags_field & COMPOUND) != 0) {
561 Assert.check((c.flags_field & UNATTRIBUTED) != 0, c);
562 attribClass(typaram.pos(), c);
563 }
564 }
565 }
566 }
568 /**
569 * Attribute the type references in a list of annotations.
570 */
571 void attribAnnotationTypes(List<JCAnnotation> annotations,
572 Env<AttrContext> env) {
573 for (List<JCAnnotation> al = annotations; al.nonEmpty(); al = al.tail) {
574 JCAnnotation a = al.head;
575 attribType(a.annotationType, env);
576 }
577 }
579 /**
580 * Attribute a "lazy constant value".
581 * @param env The env for the const value
582 * @param initializer The initializer for the const value
583 * @param type The expected type, or null
584 * @see VarSymbol#setlazyConstValue
585 */
586 public Object attribLazyConstantValue(Env<AttrContext> env,
587 JCTree.JCExpression initializer,
588 Type type) {
590 // in case no lint value has been set up for this env, scan up
591 // env stack looking for smallest enclosing env for which it is set.
592 Env<AttrContext> lintEnv = env;
593 while (lintEnv.info.lint == null)
594 lintEnv = lintEnv.next;
596 // Having found the enclosing lint value, we can initialize the lint value for this class
597 env.info.lint = lintEnv.info.lint.augment(env.info.enclVar.attributes_field, env.info.enclVar.flags());
599 Lint prevLint = chk.setLint(env.info.lint);
600 JavaFileObject prevSource = log.useSource(env.toplevel.sourcefile);
602 try {
603 Type itype = attribExpr(initializer, env, type);
604 if (itype.constValue() != null)
605 return coerce(itype, type).constValue();
606 else
607 return null;
608 } finally {
609 env.info.lint = prevLint;
610 log.useSource(prevSource);
611 }
612 }
614 /** Attribute type reference in an `extends' or `implements' clause.
615 * Supertypes of anonymous inner classes are usually already attributed.
616 *
617 * @param tree The tree making up the type reference.
618 * @param env The environment current at the reference.
619 * @param classExpected true if only a class is expected here.
620 * @param interfaceExpected true if only an interface is expected here.
621 */
622 Type attribBase(JCTree tree,
623 Env<AttrContext> env,
624 boolean classExpected,
625 boolean interfaceExpected,
626 boolean checkExtensible) {
627 Type t = tree.type != null ?
628 tree.type :
629 attribType(tree, env);
630 return checkBase(t, tree, env, classExpected, interfaceExpected, checkExtensible);
631 }
632 Type checkBase(Type t,
633 JCTree tree,
634 Env<AttrContext> env,
635 boolean classExpected,
636 boolean interfaceExpected,
637 boolean checkExtensible) {
638 if (t.isErroneous())
639 return t;
640 if (t.tag == TYPEVAR && !classExpected && !interfaceExpected) {
641 // check that type variable is already visible
642 if (t.getUpperBound() == null) {
643 log.error(tree.pos(), "illegal.forward.ref");
644 return types.createErrorType(t);
645 }
646 } else {
647 t = chk.checkClassType(tree.pos(), t, checkExtensible|!allowGenerics);
648 }
649 if (interfaceExpected && (t.tsym.flags() & INTERFACE) == 0) {
650 log.error(tree.pos(), "intf.expected.here");
651 // return errType is necessary since otherwise there might
652 // be undetected cycles which cause attribution to loop
653 return types.createErrorType(t);
654 } else if (checkExtensible &&
655 classExpected &&
656 (t.tsym.flags() & INTERFACE) != 0) {
657 log.error(tree.pos(), "no.intf.expected.here");
658 return types.createErrorType(t);
659 }
660 if (checkExtensible &&
661 ((t.tsym.flags() & FINAL) != 0)) {
662 log.error(tree.pos(),
663 "cant.inherit.from.final", t.tsym);
664 }
665 chk.checkNonCyclic(tree.pos(), t);
666 return t;
667 }
669 public void visitClassDef(JCClassDecl tree) {
670 // Local classes have not been entered yet, so we need to do it now:
671 if ((env.info.scope.owner.kind & (VAR | MTH)) != 0)
672 enter.classEnter(tree, env);
674 ClassSymbol c = tree.sym;
675 if (c == null) {
676 // exit in case something drastic went wrong during enter.
677 result = null;
678 } else {
679 // make sure class has been completed:
680 c.complete();
682 // If this class appears as an anonymous class
683 // in a superclass constructor call where
684 // no explicit outer instance is given,
685 // disable implicit outer instance from being passed.
686 // (This would be an illegal access to "this before super").
687 if (env.info.isSelfCall &&
688 env.tree.getTag() == JCTree.NEWCLASS &&
689 ((JCNewClass) env.tree).encl == null)
690 {
691 c.flags_field |= NOOUTERTHIS;
692 }
693 attribClass(tree.pos(), c);
694 result = tree.type = c.type;
695 }
696 }
698 public void visitMethodDef(JCMethodDecl tree) {
699 MethodSymbol m = tree.sym;
701 Lint lint = env.info.lint.augment(m.attributes_field, m.flags());
702 Lint prevLint = chk.setLint(lint);
703 MethodSymbol prevMethod = chk.setMethod(m);
704 try {
705 deferredLintHandler.flush(tree.pos());
706 chk.checkDeprecatedAnnotation(tree.pos(), m);
708 attribBounds(tree.typarams);
710 // If we override any other methods, check that we do so properly.
711 // JLS ???
712 if (m.isStatic()) {
713 chk.checkHideClashes(tree.pos(), env.enclClass.type, m);
714 } else {
715 chk.checkOverrideClashes(tree.pos(), env.enclClass.type, m);
716 }
717 chk.checkOverride(tree, m);
719 // Create a new environment with local scope
720 // for attributing the method.
721 Env<AttrContext> localEnv = memberEnter.methodEnv(tree, env);
723 localEnv.info.lint = lint;
725 // Enter all type parameters into the local method scope.
726 for (List<JCTypeParameter> l = tree.typarams; l.nonEmpty(); l = l.tail)
727 localEnv.info.scope.enterIfAbsent(l.head.type.tsym);
729 ClassSymbol owner = env.enclClass.sym;
730 if ((owner.flags() & ANNOTATION) != 0 &&
731 tree.params.nonEmpty())
732 log.error(tree.params.head.pos(),
733 "intf.annotation.members.cant.have.params");
735 // Attribute all value parameters.
736 for (List<JCVariableDecl> l = tree.params; l.nonEmpty(); l = l.tail) {
737 attribStat(l.head, localEnv);
738 }
740 chk.checkVarargsMethodDecl(localEnv, tree);
742 // Check that type parameters are well-formed.
743 chk.validate(tree.typarams, localEnv);
745 // Check that result type is well-formed.
746 chk.validate(tree.restype, localEnv);
748 // annotation method checks
749 if ((owner.flags() & ANNOTATION) != 0) {
750 // annotation method cannot have throws clause
751 if (tree.thrown.nonEmpty()) {
752 log.error(tree.thrown.head.pos(),
753 "throws.not.allowed.in.intf.annotation");
754 }
755 // annotation method cannot declare type-parameters
756 if (tree.typarams.nonEmpty()) {
757 log.error(tree.typarams.head.pos(),
758 "intf.annotation.members.cant.have.type.params");
759 }
760 // validate annotation method's return type (could be an annotation type)
761 chk.validateAnnotationType(tree.restype);
762 // ensure that annotation method does not clash with members of Object/Annotation
763 chk.validateAnnotationMethod(tree.pos(), m);
765 if (tree.defaultValue != null) {
766 // if default value is an annotation, check it is a well-formed
767 // annotation value (e.g. no duplicate values, no missing values, etc.)
768 chk.validateAnnotationTree(tree.defaultValue);
769 }
770 }
772 for (List<JCExpression> l = tree.thrown; l.nonEmpty(); l = l.tail)
773 chk.checkType(l.head.pos(), l.head.type, syms.throwableType);
775 if (tree.body == null) {
776 // Empty bodies are only allowed for
777 // abstract, native, or interface methods, or for methods
778 // in a retrofit signature class.
779 if ((owner.flags() & INTERFACE) == 0 &&
780 (tree.mods.flags & (ABSTRACT | NATIVE)) == 0 &&
781 !relax)
782 log.error(tree.pos(), "missing.meth.body.or.decl.abstract");
783 if (tree.defaultValue != null) {
784 if ((owner.flags() & ANNOTATION) == 0)
785 log.error(tree.pos(),
786 "default.allowed.in.intf.annotation.member");
787 }
788 } else if ((owner.flags() & INTERFACE) != 0) {
789 log.error(tree.body.pos(), "intf.meth.cant.have.body");
790 } else if ((tree.mods.flags & ABSTRACT) != 0) {
791 log.error(tree.pos(), "abstract.meth.cant.have.body");
792 } else if ((tree.mods.flags & NATIVE) != 0) {
793 log.error(tree.pos(), "native.meth.cant.have.body");
794 } else {
795 // Add an implicit super() call unless an explicit call to
796 // super(...) or this(...) is given
797 // or we are compiling class java.lang.Object.
798 if (tree.name == names.init && owner.type != syms.objectType) {
799 JCBlock body = tree.body;
800 if (body.stats.isEmpty() ||
801 !TreeInfo.isSelfCall(body.stats.head)) {
802 body.stats = body.stats.
803 prepend(memberEnter.SuperCall(make.at(body.pos),
804 List.<Type>nil(),
805 List.<JCVariableDecl>nil(),
806 false));
807 } else if ((env.enclClass.sym.flags() & ENUM) != 0 &&
808 (tree.mods.flags & GENERATEDCONSTR) == 0 &&
809 TreeInfo.isSuperCall(body.stats.head)) {
810 // enum constructors are not allowed to call super
811 // directly, so make sure there aren't any super calls
812 // in enum constructors, except in the compiler
813 // generated one.
814 log.error(tree.body.stats.head.pos(),
815 "call.to.super.not.allowed.in.enum.ctor",
816 env.enclClass.sym);
817 }
818 }
820 // Attribute method body.
821 attribStat(tree.body, localEnv);
822 }
823 localEnv.info.scope.leave();
824 result = tree.type = m.type;
825 chk.validateAnnotations(tree.mods.annotations, m);
826 }
827 finally {
828 chk.setLint(prevLint);
829 chk.setMethod(prevMethod);
830 }
831 }
833 public void visitVarDef(JCVariableDecl tree) {
834 // Local variables have not been entered yet, so we need to do it now:
835 if (env.info.scope.owner.kind == MTH) {
836 if (tree.sym != null) {
837 // parameters have already been entered
838 env.info.scope.enter(tree.sym);
839 } else {
840 memberEnter.memberEnter(tree, env);
841 annotate.flush();
842 }
843 tree.sym.flags_field |= EFFECTIVELY_FINAL;
844 }
846 VarSymbol v = tree.sym;
847 Lint lint = env.info.lint.augment(v.attributes_field, v.flags());
848 Lint prevLint = chk.setLint(lint);
850 // Check that the variable's declared type is well-formed.
851 chk.validate(tree.vartype, env);
852 deferredLintHandler.flush(tree.pos());
854 try {
855 chk.checkDeprecatedAnnotation(tree.pos(), v);
857 if (tree.init != null) {
858 if ((v.flags_field & FINAL) != 0 && tree.init.getTag() != JCTree.NEWCLASS) {
859 // In this case, `v' is final. Ensure that it's initializer is
860 // evaluated.
861 v.getConstValue(); // ensure initializer is evaluated
862 } else {
863 // Attribute initializer in a new environment
864 // with the declared variable as owner.
865 // Check that initializer conforms to variable's declared type.
866 Env<AttrContext> initEnv = memberEnter.initEnv(tree, env);
867 initEnv.info.lint = lint;
868 // In order to catch self-references, we set the variable's
869 // declaration position to maximal possible value, effectively
870 // marking the variable as undefined.
871 initEnv.info.enclVar = v;
872 attribExpr(tree.init, initEnv, v.type);
873 }
874 }
875 result = tree.type = v.type;
876 chk.validateAnnotations(tree.mods.annotations, v);
877 }
878 finally {
879 chk.setLint(prevLint);
880 }
881 }
883 public void visitSkip(JCSkip tree) {
884 result = null;
885 }
887 public void visitBlock(JCBlock tree) {
888 if (env.info.scope.owner.kind == TYP) {
889 // Block is a static or instance initializer;
890 // let the owner of the environment be a freshly
891 // created BLOCK-method.
892 Env<AttrContext> localEnv =
893 env.dup(tree, env.info.dup(env.info.scope.dupUnshared()));
894 localEnv.info.scope.owner =
895 new MethodSymbol(tree.flags | BLOCK, names.empty, null,
896 env.info.scope.owner);
897 if ((tree.flags & STATIC) != 0) localEnv.info.staticLevel++;
898 attribStats(tree.stats, localEnv);
899 } else {
900 // Create a new local environment with a local scope.
901 Env<AttrContext> localEnv =
902 env.dup(tree, env.info.dup(env.info.scope.dup()));
903 attribStats(tree.stats, localEnv);
904 localEnv.info.scope.leave();
905 }
906 result = null;
907 }
909 public void visitDoLoop(JCDoWhileLoop tree) {
910 attribStat(tree.body, env.dup(tree));
911 attribExpr(tree.cond, env, syms.booleanType);
912 result = null;
913 }
915 public void visitWhileLoop(JCWhileLoop tree) {
916 attribExpr(tree.cond, env, syms.booleanType);
917 attribStat(tree.body, env.dup(tree));
918 result = null;
919 }
921 public void visitForLoop(JCForLoop tree) {
922 Env<AttrContext> loopEnv =
923 env.dup(env.tree, env.info.dup(env.info.scope.dup()));
924 attribStats(tree.init, loopEnv);
925 if (tree.cond != null) attribExpr(tree.cond, loopEnv, syms.booleanType);
926 loopEnv.tree = tree; // before, we were not in loop!
927 attribStats(tree.step, loopEnv);
928 attribStat(tree.body, loopEnv);
929 loopEnv.info.scope.leave();
930 result = null;
931 }
933 public void visitForeachLoop(JCEnhancedForLoop tree) {
934 Env<AttrContext> loopEnv =
935 env.dup(env.tree, env.info.dup(env.info.scope.dup()));
936 attribStat(tree.var, loopEnv);
937 Type exprType = types.upperBound(attribExpr(tree.expr, loopEnv));
938 chk.checkNonVoid(tree.pos(), exprType);
939 Type elemtype = types.elemtype(exprType); // perhaps expr is an array?
940 if (elemtype == null) {
941 // or perhaps expr implements Iterable<T>?
942 Type base = types.asSuper(exprType, syms.iterableType.tsym);
943 if (base == null) {
944 log.error(tree.expr.pos(),
945 "foreach.not.applicable.to.type",
946 exprType,
947 diags.fragment("type.req.array.or.iterable"));
948 elemtype = types.createErrorType(exprType);
949 } else {
950 List<Type> iterableParams = base.allparams();
951 elemtype = iterableParams.isEmpty()
952 ? syms.objectType
953 : types.upperBound(iterableParams.head);
954 }
955 }
956 chk.checkType(tree.expr.pos(), elemtype, tree.var.sym.type);
957 loopEnv.tree = tree; // before, we were not in loop!
958 attribStat(tree.body, loopEnv);
959 loopEnv.info.scope.leave();
960 result = null;
961 }
963 public void visitLabelled(JCLabeledStatement tree) {
964 // Check that label is not used in an enclosing statement
965 Env<AttrContext> env1 = env;
966 while (env1 != null && env1.tree.getTag() != JCTree.CLASSDEF) {
967 if (env1.tree.getTag() == JCTree.LABELLED &&
968 ((JCLabeledStatement) env1.tree).label == tree.label) {
969 log.error(tree.pos(), "label.already.in.use",
970 tree.label);
971 break;
972 }
973 env1 = env1.next;
974 }
976 attribStat(tree.body, env.dup(tree));
977 result = null;
978 }
980 public void visitSwitch(JCSwitch tree) {
981 Type seltype = attribExpr(tree.selector, env);
983 Env<AttrContext> switchEnv =
984 env.dup(tree, env.info.dup(env.info.scope.dup()));
986 boolean enumSwitch =
987 allowEnums &&
988 (seltype.tsym.flags() & Flags.ENUM) != 0;
989 boolean stringSwitch = false;
990 if (types.isSameType(seltype, syms.stringType)) {
991 if (allowStringsInSwitch) {
992 stringSwitch = true;
993 } else {
994 log.error(tree.selector.pos(), "string.switch.not.supported.in.source", sourceName);
995 }
996 }
997 if (!enumSwitch && !stringSwitch)
998 seltype = chk.checkType(tree.selector.pos(), seltype, syms.intType);
1000 // Attribute all cases and
1001 // check that there are no duplicate case labels or default clauses.
1002 Set<Object> labels = new HashSet<Object>(); // The set of case labels.
1003 boolean hasDefault = false; // Is there a default label?
1004 for (List<JCCase> l = tree.cases; l.nonEmpty(); l = l.tail) {
1005 JCCase c = l.head;
1006 Env<AttrContext> caseEnv =
1007 switchEnv.dup(c, env.info.dup(switchEnv.info.scope.dup()));
1008 if (c.pat != null) {
1009 if (enumSwitch) {
1010 Symbol sym = enumConstant(c.pat, seltype);
1011 if (sym == null) {
1012 log.error(c.pat.pos(), "enum.label.must.be.unqualified.enum");
1013 } else if (!labels.add(sym)) {
1014 log.error(c.pos(), "duplicate.case.label");
1015 }
1016 } else {
1017 Type pattype = attribExpr(c.pat, switchEnv, seltype);
1018 if (pattype.tag != ERROR) {
1019 if (pattype.constValue() == null) {
1020 log.error(c.pat.pos(),
1021 (stringSwitch ? "string.const.req" : "const.expr.req"));
1022 } else if (labels.contains(pattype.constValue())) {
1023 log.error(c.pos(), "duplicate.case.label");
1024 } else {
1025 labels.add(pattype.constValue());
1026 }
1027 }
1028 }
1029 } else if (hasDefault) {
1030 log.error(c.pos(), "duplicate.default.label");
1031 } else {
1032 hasDefault = true;
1033 }
1034 attribStats(c.stats, caseEnv);
1035 caseEnv.info.scope.leave();
1036 addVars(c.stats, switchEnv.info.scope);
1037 }
1039 switchEnv.info.scope.leave();
1040 result = null;
1041 }
1042 // where
1043 /** Add any variables defined in stats to the switch scope. */
1044 private static void addVars(List<JCStatement> stats, Scope switchScope) {
1045 for (;stats.nonEmpty(); stats = stats.tail) {
1046 JCTree stat = stats.head;
1047 if (stat.getTag() == JCTree.VARDEF)
1048 switchScope.enter(((JCVariableDecl) stat).sym);
1049 }
1050 }
1051 // where
1052 /** Return the selected enumeration constant symbol, or null. */
1053 private Symbol enumConstant(JCTree tree, Type enumType) {
1054 if (tree.getTag() != JCTree.IDENT) {
1055 log.error(tree.pos(), "enum.label.must.be.unqualified.enum");
1056 return syms.errSymbol;
1057 }
1058 JCIdent ident = (JCIdent)tree;
1059 Name name = ident.name;
1060 for (Scope.Entry e = enumType.tsym.members().lookup(name);
1061 e.scope != null; e = e.next()) {
1062 if (e.sym.kind == VAR) {
1063 Symbol s = ident.sym = e.sym;
1064 ((VarSymbol)s).getConstValue(); // ensure initializer is evaluated
1065 ident.type = s.type;
1066 return ((s.flags_field & Flags.ENUM) == 0)
1067 ? null : s;
1068 }
1069 }
1070 return null;
1071 }
1073 public void visitSynchronized(JCSynchronized tree) {
1074 chk.checkRefType(tree.pos(), attribExpr(tree.lock, env));
1075 attribStat(tree.body, env);
1076 result = null;
1077 }
1079 public void visitTry(JCTry tree) {
1080 // Create a new local environment with a local
1081 Env<AttrContext> localEnv = env.dup(tree, env.info.dup(env.info.scope.dup()));
1082 boolean isTryWithResource = tree.resources.nonEmpty();
1083 // Create a nested environment for attributing the try block if needed
1084 Env<AttrContext> tryEnv = isTryWithResource ?
1085 env.dup(tree, localEnv.info.dup(localEnv.info.scope.dup())) :
1086 localEnv;
1087 // Attribute resource declarations
1088 for (JCTree resource : tree.resources) {
1089 if (resource.getTag() == JCTree.VARDEF) {
1090 attribStat(resource, tryEnv);
1091 chk.checkType(resource, resource.type, syms.autoCloseableType, "try.not.applicable.to.type");
1092 VarSymbol var = (VarSymbol)TreeInfo.symbolFor(resource);
1093 var.setData(ElementKind.RESOURCE_VARIABLE);
1094 } else {
1095 attribExpr(resource, tryEnv, syms.autoCloseableType, "try.not.applicable.to.type");
1096 }
1097 }
1098 // Attribute body
1099 attribStat(tree.body, tryEnv);
1100 if (isTryWithResource)
1101 tryEnv.info.scope.leave();
1103 // Attribute catch clauses
1104 for (List<JCCatch> l = tree.catchers; l.nonEmpty(); l = l.tail) {
1105 JCCatch c = l.head;
1106 Env<AttrContext> catchEnv =
1107 localEnv.dup(c, localEnv.info.dup(localEnv.info.scope.dup()));
1108 Type ctype = attribStat(c.param, catchEnv);
1109 if (TreeInfo.isMultiCatch(c)) {
1110 //multi-catch parameter is implicitly marked as final
1111 c.param.sym.flags_field |= FINAL | DISJUNCTION;
1112 }
1113 if (c.param.sym.kind == Kinds.VAR) {
1114 c.param.sym.setData(ElementKind.EXCEPTION_PARAMETER);
1115 }
1116 chk.checkType(c.param.vartype.pos(),
1117 chk.checkClassType(c.param.vartype.pos(), ctype),
1118 syms.throwableType);
1119 attribStat(c.body, catchEnv);
1120 catchEnv.info.scope.leave();
1121 }
1123 // Attribute finalizer
1124 if (tree.finalizer != null) attribStat(tree.finalizer, localEnv);
1126 localEnv.info.scope.leave();
1127 result = null;
1128 }
1130 public void visitConditional(JCConditional tree) {
1131 attribExpr(tree.cond, env, syms.booleanType);
1132 attribExpr(tree.truepart, env);
1133 attribExpr(tree.falsepart, env);
1134 result = check(tree,
1135 capture(condType(tree.pos(), tree.cond.type,
1136 tree.truepart.type, tree.falsepart.type)),
1137 VAL, pkind, pt);
1138 }
1139 //where
1140 /** Compute the type of a conditional expression, after
1141 * checking that it exists. See Spec 15.25.
1142 *
1143 * @param pos The source position to be used for
1144 * error diagnostics.
1145 * @param condtype The type of the expression's condition.
1146 * @param thentype The type of the expression's then-part.
1147 * @param elsetype The type of the expression's else-part.
1148 */
1149 private Type condType(DiagnosticPosition pos,
1150 Type condtype,
1151 Type thentype,
1152 Type elsetype) {
1153 Type ctype = condType1(pos, condtype, thentype, elsetype);
1155 // If condition and both arms are numeric constants,
1156 // evaluate at compile-time.
1157 return ((condtype.constValue() != null) &&
1158 (thentype.constValue() != null) &&
1159 (elsetype.constValue() != null))
1160 ? cfolder.coerce(condtype.isTrue()?thentype:elsetype, ctype)
1161 : ctype;
1162 }
1163 /** Compute the type of a conditional expression, after
1164 * checking that it exists. Does not take into
1165 * account the special case where condition and both arms
1166 * are constants.
1167 *
1168 * @param pos The source position to be used for error
1169 * diagnostics.
1170 * @param condtype The type of the expression's condition.
1171 * @param thentype The type of the expression's then-part.
1172 * @param elsetype The type of the expression's else-part.
1173 */
1174 private Type condType1(DiagnosticPosition pos, Type condtype,
1175 Type thentype, Type elsetype) {
1176 // If same type, that is the result
1177 if (types.isSameType(thentype, elsetype))
1178 return thentype.baseType();
1180 Type thenUnboxed = (!allowBoxing || thentype.isPrimitive())
1181 ? thentype : types.unboxedType(thentype);
1182 Type elseUnboxed = (!allowBoxing || elsetype.isPrimitive())
1183 ? elsetype : types.unboxedType(elsetype);
1185 // Otherwise, if both arms can be converted to a numeric
1186 // type, return the least numeric type that fits both arms
1187 // (i.e. return larger of the two, or return int if one
1188 // arm is short, the other is char).
1189 if (thenUnboxed.isPrimitive() && elseUnboxed.isPrimitive()) {
1190 // If one arm has an integer subrange type (i.e., byte,
1191 // short, or char), and the other is an integer constant
1192 // that fits into the subrange, return the subrange type.
1193 if (thenUnboxed.tag < INT && elseUnboxed.tag == INT &&
1194 types.isAssignable(elseUnboxed, thenUnboxed))
1195 return thenUnboxed.baseType();
1196 if (elseUnboxed.tag < INT && thenUnboxed.tag == INT &&
1197 types.isAssignable(thenUnboxed, elseUnboxed))
1198 return elseUnboxed.baseType();
1200 for (int i = BYTE; i < VOID; i++) {
1201 Type candidate = syms.typeOfTag[i];
1202 if (types.isSubtype(thenUnboxed, candidate) &&
1203 types.isSubtype(elseUnboxed, candidate))
1204 return candidate;
1205 }
1206 }
1208 // Those were all the cases that could result in a primitive
1209 if (allowBoxing) {
1210 if (thentype.isPrimitive())
1211 thentype = types.boxedClass(thentype).type;
1212 if (elsetype.isPrimitive())
1213 elsetype = types.boxedClass(elsetype).type;
1214 }
1216 if (types.isSubtype(thentype, elsetype))
1217 return elsetype.baseType();
1218 if (types.isSubtype(elsetype, thentype))
1219 return thentype.baseType();
1221 if (!allowBoxing || thentype.tag == VOID || elsetype.tag == VOID) {
1222 log.error(pos, "neither.conditional.subtype",
1223 thentype, elsetype);
1224 return thentype.baseType();
1225 }
1227 // both are known to be reference types. The result is
1228 // lub(thentype,elsetype). This cannot fail, as it will
1229 // always be possible to infer "Object" if nothing better.
1230 return types.lub(thentype.baseType(), elsetype.baseType());
1231 }
1233 public void visitIf(JCIf tree) {
1234 attribExpr(tree.cond, env, syms.booleanType);
1235 attribStat(tree.thenpart, env);
1236 if (tree.elsepart != null)
1237 attribStat(tree.elsepart, env);
1238 chk.checkEmptyIf(tree);
1239 result = null;
1240 }
1242 public void visitExec(JCExpressionStatement tree) {
1243 //a fresh environment is required for 292 inference to work properly ---
1244 //see Infer.instantiatePolymorphicSignatureInstance()
1245 Env<AttrContext> localEnv = env.dup(tree);
1246 attribExpr(tree.expr, localEnv);
1247 result = null;
1248 }
1250 public void visitBreak(JCBreak tree) {
1251 tree.target = findJumpTarget(tree.pos(), tree.getTag(), tree.label, env);
1252 result = null;
1253 }
1255 public void visitContinue(JCContinue tree) {
1256 tree.target = findJumpTarget(tree.pos(), tree.getTag(), tree.label, env);
1257 result = null;
1258 }
1259 //where
1260 /** Return the target of a break or continue statement, if it exists,
1261 * report an error if not.
1262 * Note: The target of a labelled break or continue is the
1263 * (non-labelled) statement tree referred to by the label,
1264 * not the tree representing the labelled statement itself.
1265 *
1266 * @param pos The position to be used for error diagnostics
1267 * @param tag The tag of the jump statement. This is either
1268 * Tree.BREAK or Tree.CONTINUE.
1269 * @param label The label of the jump statement, or null if no
1270 * label is given.
1271 * @param env The environment current at the jump statement.
1272 */
1273 private JCTree findJumpTarget(DiagnosticPosition pos,
1274 int tag,
1275 Name label,
1276 Env<AttrContext> env) {
1277 // Search environments outwards from the point of jump.
1278 Env<AttrContext> env1 = env;
1279 LOOP:
1280 while (env1 != null) {
1281 switch (env1.tree.getTag()) {
1282 case JCTree.LABELLED:
1283 JCLabeledStatement labelled = (JCLabeledStatement)env1.tree;
1284 if (label == labelled.label) {
1285 // If jump is a continue, check that target is a loop.
1286 if (tag == JCTree.CONTINUE) {
1287 if (labelled.body.getTag() != JCTree.DOLOOP &&
1288 labelled.body.getTag() != JCTree.WHILELOOP &&
1289 labelled.body.getTag() != JCTree.FORLOOP &&
1290 labelled.body.getTag() != JCTree.FOREACHLOOP)
1291 log.error(pos, "not.loop.label", label);
1292 // Found labelled statement target, now go inwards
1293 // to next non-labelled tree.
1294 return TreeInfo.referencedStatement(labelled);
1295 } else {
1296 return labelled;
1297 }
1298 }
1299 break;
1300 case JCTree.DOLOOP:
1301 case JCTree.WHILELOOP:
1302 case JCTree.FORLOOP:
1303 case JCTree.FOREACHLOOP:
1304 if (label == null) return env1.tree;
1305 break;
1306 case JCTree.SWITCH:
1307 if (label == null && tag == JCTree.BREAK) return env1.tree;
1308 break;
1309 case JCTree.METHODDEF:
1310 case JCTree.CLASSDEF:
1311 break LOOP;
1312 default:
1313 }
1314 env1 = env1.next;
1315 }
1316 if (label != null)
1317 log.error(pos, "undef.label", label);
1318 else if (tag == JCTree.CONTINUE)
1319 log.error(pos, "cont.outside.loop");
1320 else
1321 log.error(pos, "break.outside.switch.loop");
1322 return null;
1323 }
1325 public void visitReturn(JCReturn tree) {
1326 // Check that there is an enclosing method which is
1327 // nested within than the enclosing class.
1328 if (env.enclMethod == null ||
1329 env.enclMethod.sym.owner != env.enclClass.sym) {
1330 log.error(tree.pos(), "ret.outside.meth");
1332 } else {
1333 // Attribute return expression, if it exists, and check that
1334 // it conforms to result type of enclosing method.
1335 Symbol m = env.enclMethod.sym;
1336 if (m.type.getReturnType().tag == VOID) {
1337 if (tree.expr != null)
1338 log.error(tree.expr.pos(),
1339 "cant.ret.val.from.meth.decl.void");
1340 } else if (tree.expr == null) {
1341 log.error(tree.pos(), "missing.ret.val");
1342 } else {
1343 attribExpr(tree.expr, env, m.type.getReturnType());
1344 }
1345 }
1346 result = null;
1347 }
1349 public void visitThrow(JCThrow tree) {
1350 attribExpr(tree.expr, env, syms.throwableType);
1351 result = null;
1352 }
1354 public void visitAssert(JCAssert tree) {
1355 attribExpr(tree.cond, env, syms.booleanType);
1356 if (tree.detail != null) {
1357 chk.checkNonVoid(tree.detail.pos(), attribExpr(tree.detail, env));
1358 }
1359 result = null;
1360 }
1362 /** Visitor method for method invocations.
1363 * NOTE: The method part of an application will have in its type field
1364 * the return type of the method, not the method's type itself!
1365 */
1366 public void visitApply(JCMethodInvocation tree) {
1367 // The local environment of a method application is
1368 // a new environment nested in the current one.
1369 Env<AttrContext> localEnv = env.dup(tree, env.info.dup());
1371 // The types of the actual method arguments.
1372 List<Type> argtypes;
1374 // The types of the actual method type arguments.
1375 List<Type> typeargtypes = null;
1377 Name methName = TreeInfo.name(tree.meth);
1379 boolean isConstructorCall =
1380 methName == names._this || methName == names._super;
1382 if (isConstructorCall) {
1383 // We are seeing a ...this(...) or ...super(...) call.
1384 // Check that this is the first statement in a constructor.
1385 if (checkFirstConstructorStat(tree, env)) {
1387 // Record the fact
1388 // that this is a constructor call (using isSelfCall).
1389 localEnv.info.isSelfCall = true;
1391 // Attribute arguments, yielding list of argument types.
1392 argtypes = attribArgs(tree.args, localEnv);
1393 typeargtypes = attribTypes(tree.typeargs, localEnv);
1395 // Variable `site' points to the class in which the called
1396 // constructor is defined.
1397 Type site = env.enclClass.sym.type;
1398 if (methName == names._super) {
1399 if (site == syms.objectType) {
1400 log.error(tree.meth.pos(), "no.superclass", site);
1401 site = types.createErrorType(syms.objectType);
1402 } else {
1403 site = types.supertype(site);
1404 }
1405 }
1407 if (site.tag == CLASS) {
1408 Type encl = site.getEnclosingType();
1409 while (encl != null && encl.tag == TYPEVAR)
1410 encl = encl.getUpperBound();
1411 if (encl.tag == CLASS) {
1412 // we are calling a nested class
1414 if (tree.meth.getTag() == JCTree.SELECT) {
1415 JCTree qualifier = ((JCFieldAccess) tree.meth).selected;
1417 // We are seeing a prefixed call, of the form
1418 // <expr>.super(...).
1419 // Check that the prefix expression conforms
1420 // to the outer instance type of the class.
1421 chk.checkRefType(qualifier.pos(),
1422 attribExpr(qualifier, localEnv,
1423 encl));
1424 } else if (methName == names._super) {
1425 // qualifier omitted; check for existence
1426 // of an appropriate implicit qualifier.
1427 rs.resolveImplicitThis(tree.meth.pos(),
1428 localEnv, site, true);
1429 }
1430 } else if (tree.meth.getTag() == JCTree.SELECT) {
1431 log.error(tree.meth.pos(), "illegal.qual.not.icls",
1432 site.tsym);
1433 }
1435 // if we're calling a java.lang.Enum constructor,
1436 // prefix the implicit String and int parameters
1437 if (site.tsym == syms.enumSym && allowEnums)
1438 argtypes = argtypes.prepend(syms.intType).prepend(syms.stringType);
1440 // Resolve the called constructor under the assumption
1441 // that we are referring to a superclass instance of the
1442 // current instance (JLS ???).
1443 boolean selectSuperPrev = localEnv.info.selectSuper;
1444 localEnv.info.selectSuper = true;
1445 localEnv.info.varArgs = false;
1446 Symbol sym = rs.resolveConstructor(
1447 tree.meth.pos(), localEnv, site, argtypes, typeargtypes);
1448 localEnv.info.selectSuper = selectSuperPrev;
1450 // Set method symbol to resolved constructor...
1451 TreeInfo.setSymbol(tree.meth, sym);
1453 // ...and check that it is legal in the current context.
1454 // (this will also set the tree's type)
1455 Type mpt = newMethTemplate(argtypes, typeargtypes);
1456 checkId(tree.meth, site, sym, localEnv, MTH,
1457 mpt, tree.varargsElement != null);
1458 }
1459 // Otherwise, `site' is an error type and we do nothing
1460 }
1461 result = tree.type = syms.voidType;
1462 } else {
1463 // Otherwise, we are seeing a regular method call.
1464 // Attribute the arguments, yielding list of argument types, ...
1465 argtypes = attribArgs(tree.args, localEnv);
1466 typeargtypes = attribAnyTypes(tree.typeargs, localEnv);
1468 // ... and attribute the method using as a prototype a methodtype
1469 // whose formal argument types is exactly the list of actual
1470 // arguments (this will also set the method symbol).
1471 Type mpt = newMethTemplate(argtypes, typeargtypes);
1472 localEnv.info.varArgs = false;
1473 Type mtype = attribExpr(tree.meth, localEnv, mpt);
1474 if (localEnv.info.varArgs)
1475 Assert.check(mtype.isErroneous() || tree.varargsElement != null);
1477 // Compute the result type.
1478 Type restype = mtype.getReturnType();
1479 if (restype.tag == WILDCARD)
1480 throw new AssertionError(mtype);
1482 // as a special case, array.clone() has a result that is
1483 // the same as static type of the array being cloned
1484 if (tree.meth.getTag() == JCTree.SELECT &&
1485 allowCovariantReturns &&
1486 methName == names.clone &&
1487 types.isArray(((JCFieldAccess) tree.meth).selected.type))
1488 restype = ((JCFieldAccess) tree.meth).selected.type;
1490 // as a special case, x.getClass() has type Class<? extends |X|>
1491 if (allowGenerics &&
1492 methName == names.getClass && tree.args.isEmpty()) {
1493 Type qualifier = (tree.meth.getTag() == JCTree.SELECT)
1494 ? ((JCFieldAccess) tree.meth).selected.type
1495 : env.enclClass.sym.type;
1496 restype = new
1497 ClassType(restype.getEnclosingType(),
1498 List.<Type>of(new WildcardType(types.erasure(qualifier),
1499 BoundKind.EXTENDS,
1500 syms.boundClass)),
1501 restype.tsym);
1502 }
1504 chk.checkRefTypes(tree.typeargs, typeargtypes);
1506 // Check that value of resulting type is admissible in the
1507 // current context. Also, capture the return type
1508 result = check(tree, capture(restype), VAL, pkind, pt);
1509 }
1510 chk.validate(tree.typeargs, localEnv);
1511 }
1512 //where
1513 /** Check that given application node appears as first statement
1514 * in a constructor call.
1515 * @param tree The application node
1516 * @param env The environment current at the application.
1517 */
1518 boolean checkFirstConstructorStat(JCMethodInvocation tree, Env<AttrContext> env) {
1519 JCMethodDecl enclMethod = env.enclMethod;
1520 if (enclMethod != null && enclMethod.name == names.init) {
1521 JCBlock body = enclMethod.body;
1522 if (body.stats.head.getTag() == JCTree.EXEC &&
1523 ((JCExpressionStatement) body.stats.head).expr == tree)
1524 return true;
1525 }
1526 log.error(tree.pos(),"call.must.be.first.stmt.in.ctor",
1527 TreeInfo.name(tree.meth));
1528 return false;
1529 }
1531 /** Obtain a method type with given argument types.
1532 */
1533 Type newMethTemplate(List<Type> argtypes, List<Type> typeargtypes) {
1534 MethodType mt = new MethodType(argtypes, null, null, syms.methodClass);
1535 return (typeargtypes == null) ? mt : (Type)new ForAll(typeargtypes, mt);
1536 }
1538 public void visitNewClass(JCNewClass tree) {
1539 Type owntype = types.createErrorType(tree.type);
1541 // The local environment of a class creation is
1542 // a new environment nested in the current one.
1543 Env<AttrContext> localEnv = env.dup(tree, env.info.dup());
1545 // The anonymous inner class definition of the new expression,
1546 // if one is defined by it.
1547 JCClassDecl cdef = tree.def;
1549 // If enclosing class is given, attribute it, and
1550 // complete class name to be fully qualified
1551 JCExpression clazz = tree.clazz; // Class field following new
1552 JCExpression clazzid = // Identifier in class field
1553 (clazz.getTag() == JCTree.TYPEAPPLY)
1554 ? ((JCTypeApply) clazz).clazz
1555 : clazz;
1557 JCExpression clazzid1 = clazzid; // The same in fully qualified form
1559 if (tree.encl != null) {
1560 // We are seeing a qualified new, of the form
1561 // <expr>.new C <...> (...) ...
1562 // In this case, we let clazz stand for the name of the
1563 // allocated class C prefixed with the type of the qualifier
1564 // expression, so that we can
1565 // resolve it with standard techniques later. I.e., if
1566 // <expr> has type T, then <expr>.new C <...> (...)
1567 // yields a clazz T.C.
1568 Type encltype = chk.checkRefType(tree.encl.pos(),
1569 attribExpr(tree.encl, env));
1570 clazzid1 = make.at(clazz.pos).Select(make.Type(encltype),
1571 ((JCIdent) clazzid).name);
1572 if (clazz.getTag() == JCTree.TYPEAPPLY)
1573 clazz = make.at(tree.pos).
1574 TypeApply(clazzid1,
1575 ((JCTypeApply) clazz).arguments);
1576 else
1577 clazz = clazzid1;
1578 }
1580 // Attribute clazz expression and store
1581 // symbol + type back into the attributed tree.
1582 Type clazztype = attribType(clazz, env);
1583 Pair<Scope,Scope> mapping = getSyntheticScopeMapping(clazztype, cdef != null);
1584 clazztype = chk.checkDiamond(tree, clazztype);
1585 chk.validate(clazz, localEnv);
1586 if (tree.encl != null) {
1587 // We have to work in this case to store
1588 // symbol + type back into the attributed tree.
1589 tree.clazz.type = clazztype;
1590 TreeInfo.setSymbol(clazzid, TreeInfo.symbol(clazzid1));
1591 clazzid.type = ((JCIdent) clazzid).sym.type;
1592 if (!clazztype.isErroneous()) {
1593 if (cdef != null && clazztype.tsym.isInterface()) {
1594 log.error(tree.encl.pos(), "anon.class.impl.intf.no.qual.for.new");
1595 } else if (clazztype.tsym.isStatic()) {
1596 log.error(tree.encl.pos(), "qualified.new.of.static.class", clazztype.tsym);
1597 }
1598 }
1599 } else if (!clazztype.tsym.isInterface() &&
1600 clazztype.getEnclosingType().tag == CLASS) {
1601 // Check for the existence of an apropos outer instance
1602 rs.resolveImplicitThis(tree.pos(), env, clazztype);
1603 }
1605 // Attribute constructor arguments.
1606 List<Type> argtypes = attribArgs(tree.args, localEnv);
1607 List<Type> typeargtypes = attribTypes(tree.typeargs, localEnv);
1609 if (TreeInfo.isDiamond(tree) && !clazztype.isErroneous()) {
1610 clazztype = attribDiamond(localEnv, tree, clazztype, mapping, argtypes, typeargtypes);
1611 clazz.type = clazztype;
1612 } else if (allowDiamondFinder &&
1613 tree.def == null &&
1614 !clazztype.isErroneous() &&
1615 clazztype.getTypeArguments().nonEmpty() &&
1616 findDiamonds) {
1617 boolean prevDeferDiags = log.deferDiagnostics;
1618 Queue<JCDiagnostic> prevDeferredDiags = log.deferredDiagnostics;
1619 Type inferred = null;
1620 try {
1621 //disable diamond-related diagnostics
1622 log.deferDiagnostics = true;
1623 log.deferredDiagnostics = ListBuffer.lb();
1624 inferred = attribDiamond(localEnv,
1625 tree,
1626 clazztype,
1627 mapping,
1628 argtypes,
1629 typeargtypes);
1630 }
1631 finally {
1632 log.deferDiagnostics = prevDeferDiags;
1633 log.deferredDiagnostics = prevDeferredDiags;
1634 }
1635 if (inferred != null &&
1636 !inferred.isErroneous() &&
1637 inferred.tag == CLASS &&
1638 types.isAssignable(inferred, pt.tag == NONE ? clazztype : pt, Warner.noWarnings)) {
1639 String key = types.isSameType(clazztype, inferred) ?
1640 "diamond.redundant.args" :
1641 "diamond.redundant.args.1";
1642 log.warning(tree.clazz.pos(), key, clazztype, inferred);
1643 }
1644 }
1646 // If we have made no mistakes in the class type...
1647 if (clazztype.tag == CLASS) {
1648 // Enums may not be instantiated except implicitly
1649 if (allowEnums &&
1650 (clazztype.tsym.flags_field&Flags.ENUM) != 0 &&
1651 (env.tree.getTag() != JCTree.VARDEF ||
1652 (((JCVariableDecl) env.tree).mods.flags&Flags.ENUM) == 0 ||
1653 ((JCVariableDecl) env.tree).init != tree))
1654 log.error(tree.pos(), "enum.cant.be.instantiated");
1655 // Check that class is not abstract
1656 if (cdef == null &&
1657 (clazztype.tsym.flags() & (ABSTRACT | INTERFACE)) != 0) {
1658 log.error(tree.pos(), "abstract.cant.be.instantiated",
1659 clazztype.tsym);
1660 } else if (cdef != null && clazztype.tsym.isInterface()) {
1661 // Check that no constructor arguments are given to
1662 // anonymous classes implementing an interface
1663 if (!argtypes.isEmpty())
1664 log.error(tree.args.head.pos(), "anon.class.impl.intf.no.args");
1666 if (!typeargtypes.isEmpty())
1667 log.error(tree.typeargs.head.pos(), "anon.class.impl.intf.no.typeargs");
1669 // Error recovery: pretend no arguments were supplied.
1670 argtypes = List.nil();
1671 typeargtypes = List.nil();
1672 }
1674 // Resolve the called constructor under the assumption
1675 // that we are referring to a superclass instance of the
1676 // current instance (JLS ???).
1677 else {
1678 localEnv.info.selectSuper = cdef != null;
1679 localEnv.info.varArgs = false;
1680 tree.constructor = rs.resolveConstructor(
1681 tree.pos(), localEnv, clazztype, argtypes, typeargtypes);
1682 tree.constructorType = tree.constructor.type.isErroneous() ?
1683 syms.errType :
1684 checkMethod(clazztype,
1685 tree.constructor,
1686 localEnv,
1687 tree.args,
1688 argtypes,
1689 typeargtypes,
1690 localEnv.info.varArgs);
1691 if (localEnv.info.varArgs)
1692 Assert.check(tree.constructorType.isErroneous() || tree.varargsElement != null);
1693 }
1695 if (cdef != null) {
1696 // We are seeing an anonymous class instance creation.
1697 // In this case, the class instance creation
1698 // expression
1699 //
1700 // E.new <typeargs1>C<typargs2>(args) { ... }
1701 //
1702 // is represented internally as
1703 //
1704 // E . new <typeargs1>C<typargs2>(args) ( class <empty-name> { ... } ) .
1705 //
1706 // This expression is then *transformed* as follows:
1707 //
1708 // (1) add a STATIC flag to the class definition
1709 // if the current environment is static
1710 // (2) add an extends or implements clause
1711 // (3) add a constructor.
1712 //
1713 // For instance, if C is a class, and ET is the type of E,
1714 // the expression
1715 //
1716 // E.new <typeargs1>C<typargs2>(args) { ... }
1717 //
1718 // is translated to (where X is a fresh name and typarams is the
1719 // parameter list of the super constructor):
1720 //
1721 // new <typeargs1>X(<*nullchk*>E, args) where
1722 // X extends C<typargs2> {
1723 // <typarams> X(ET e, args) {
1724 // e.<typeargs1>super(args)
1725 // }
1726 // ...
1727 // }
1728 if (Resolve.isStatic(env)) cdef.mods.flags |= STATIC;
1730 if (clazztype.tsym.isInterface()) {
1731 cdef.implementing = List.of(clazz);
1732 } else {
1733 cdef.extending = clazz;
1734 }
1736 attribStat(cdef, localEnv);
1738 // If an outer instance is given,
1739 // prefix it to the constructor arguments
1740 // and delete it from the new expression
1741 if (tree.encl != null && !clazztype.tsym.isInterface()) {
1742 tree.args = tree.args.prepend(makeNullCheck(tree.encl));
1743 argtypes = argtypes.prepend(tree.encl.type);
1744 tree.encl = null;
1745 }
1747 // Reassign clazztype and recompute constructor.
1748 clazztype = cdef.sym.type;
1749 Symbol sym = rs.resolveConstructor(
1750 tree.pos(), localEnv, clazztype, argtypes,
1751 typeargtypes, true, tree.varargsElement != null);
1752 Assert.check(sym.kind < AMBIGUOUS || tree.constructor.type.isErroneous());
1753 tree.constructor = sym;
1754 if (tree.constructor.kind > ERRONEOUS) {
1755 tree.constructorType = syms.errType;
1756 }
1757 else {
1758 tree.constructorType = checkMethod(clazztype,
1759 tree.constructor,
1760 localEnv,
1761 tree.args,
1762 argtypes,
1763 typeargtypes,
1764 localEnv.info.varArgs);
1765 }
1766 }
1768 if (tree.constructor != null && tree.constructor.kind == MTH)
1769 owntype = clazztype;
1770 }
1771 result = check(tree, owntype, VAL, pkind, pt);
1772 chk.validate(tree.typeargs, localEnv);
1773 }
1775 Type attribDiamond(Env<AttrContext> env,
1776 JCNewClass tree,
1777 Type clazztype,
1778 Pair<Scope, Scope> mapping,
1779 List<Type> argtypes,
1780 List<Type> typeargtypes) {
1781 if (clazztype.isErroneous() || mapping == erroneousMapping) {
1782 //if the type of the instance creation expression is erroneous,
1783 //or something prevented us to form a valid mapping, return the
1784 //(possibly erroneous) type unchanged
1785 return clazztype;
1786 }
1787 else if (clazztype.isInterface()) {
1788 //if the type of the instance creation expression is an interface
1789 //skip the method resolution step (JLS 15.12.2.7). The type to be
1790 //inferred is of the kind <X1,X2, ... Xn>C<X1,X2, ... Xn>
1791 clazztype = new ForAll(clazztype.tsym.type.allparams(), clazztype.tsym.type) {
1792 @Override
1793 public List<Type> getConstraints(TypeVar tv, ConstraintKind ck) {
1794 switch (ck) {
1795 case EXTENDS: return types.getBounds(tv);
1796 default: return List.nil();
1797 }
1798 }
1799 @Override
1800 public Type inst(List<Type> inferred, Types types) throws Infer.NoInstanceException {
1801 // check that inferred bounds conform to their bounds
1802 infer.checkWithinBounds(tvars,
1803 types.subst(tvars, tvars, inferred), Warner.noWarnings);
1804 return super.inst(inferred, types);
1805 }
1806 };
1807 } else {
1808 //if the type of the instance creation expression is a class type
1809 //apply method resolution inference (JLS 15.12.2.7). The return type
1810 //of the resolved constructor will be a partially instantiated type
1811 ((ClassSymbol) clazztype.tsym).members_field = mapping.snd;
1812 Symbol constructor;
1813 try {
1814 constructor = rs.resolveDiamond(tree.pos(),
1815 env,
1816 clazztype.tsym.type,
1817 argtypes,
1818 typeargtypes);
1819 } finally {
1820 ((ClassSymbol) clazztype.tsym).members_field = mapping.fst;
1821 }
1822 if (constructor.kind == MTH) {
1823 ClassType ct = new ClassType(clazztype.getEnclosingType(),
1824 clazztype.tsym.type.getTypeArguments(),
1825 clazztype.tsym);
1826 clazztype = checkMethod(ct,
1827 constructor,
1828 env,
1829 tree.args,
1830 argtypes,
1831 typeargtypes,
1832 env.info.varArgs).getReturnType();
1833 } else {
1834 clazztype = syms.errType;
1835 }
1836 }
1837 if (clazztype.tag == FORALL && !pt.isErroneous()) {
1838 //if the resolved constructor's return type has some uninferred
1839 //type-variables, infer them using the expected type and declared
1840 //bounds (JLS 15.12.2.8).
1841 try {
1842 clazztype = infer.instantiateExpr((ForAll) clazztype,
1843 pt.tag == NONE ? syms.objectType : pt,
1844 Warner.noWarnings);
1845 } catch (Infer.InferenceException ex) {
1846 //an error occurred while inferring uninstantiated type-variables
1847 log.error(tree.clazz.pos(),
1848 "cant.apply.diamond.1",
1849 diags.fragment("diamond", clazztype.tsym),
1850 ex.diagnostic);
1851 }
1852 }
1853 return chk.checkClassType(tree.clazz.pos(),
1854 clazztype,
1855 true);
1856 }
1858 /** Creates a synthetic scope containing fake generic constructors.
1859 * Assuming that the original scope contains a constructor of the kind:
1860 * Foo(X x, Y y), where X,Y are class type-variables declared in Foo,
1861 * the synthetic scope is added a generic constructor of the kind:
1862 * <X,Y>Foo<X,Y>(X x, Y y). This is crucial in order to enable diamond
1863 * inference. The inferred return type of the synthetic constructor IS
1864 * the inferred type for the diamond operator.
1865 */
1866 private Pair<Scope, Scope> getSyntheticScopeMapping(Type ctype, boolean overrideProtectedAccess) {
1867 if (ctype.tag != CLASS) {
1868 return erroneousMapping;
1869 }
1870 Pair<Scope, Scope> mapping =
1871 new Pair<Scope, Scope>(ctype.tsym.members(), new Scope(ctype.tsym));
1872 List<Type> typevars = ctype.tsym.type.getTypeArguments();
1873 for (Scope.Entry e = mapping.fst.lookup(names.init);
1874 e.scope != null;
1875 e = e.next()) {
1876 MethodSymbol newConstr = (MethodSymbol) e.sym.clone(ctype.tsym);
1877 if (overrideProtectedAccess && (newConstr.flags() & PROTECTED) != 0) {
1878 //make protected constructor public (this is required for
1879 //anonymous inner class creation expressions using diamond)
1880 newConstr.flags_field |= PUBLIC;
1881 newConstr.flags_field &= ~PROTECTED;
1882 }
1883 newConstr.name = names.init;
1884 List<Type> oldTypeargs = List.nil();
1885 if (newConstr.type.tag == FORALL) {
1886 oldTypeargs = ((ForAll) newConstr.type).tvars;
1887 }
1888 newConstr.type = new MethodType(newConstr.type.getParameterTypes(),
1889 new ClassType(ctype.getEnclosingType(), ctype.tsym.type.getTypeArguments(), ctype.tsym),
1890 newConstr.type.getThrownTypes(),
1891 syms.methodClass);
1892 newConstr.type = new ForAll(typevars.prependList(oldTypeargs), newConstr.type);
1893 mapping.snd.enter(newConstr);
1894 }
1895 return mapping;
1896 }
1898 private final Pair<Scope,Scope> erroneousMapping = new Pair<Scope,Scope>(null, null);
1900 /** Make an attributed null check tree.
1901 */
1902 public JCExpression makeNullCheck(JCExpression arg) {
1903 // optimization: X.this is never null; skip null check
1904 Name name = TreeInfo.name(arg);
1905 if (name == names._this || name == names._super) return arg;
1907 int optag = JCTree.NULLCHK;
1908 JCUnary tree = make.at(arg.pos).Unary(optag, arg);
1909 tree.operator = syms.nullcheck;
1910 tree.type = arg.type;
1911 return tree;
1912 }
1914 public void visitNewArray(JCNewArray tree) {
1915 Type owntype = types.createErrorType(tree.type);
1916 Type elemtype;
1917 if (tree.elemtype != null) {
1918 elemtype = attribType(tree.elemtype, env);
1919 chk.validate(tree.elemtype, env);
1920 owntype = elemtype;
1921 for (List<JCExpression> l = tree.dims; l.nonEmpty(); l = l.tail) {
1922 attribExpr(l.head, env, syms.intType);
1923 owntype = new ArrayType(owntype, syms.arrayClass);
1924 }
1925 } else {
1926 // we are seeing an untyped aggregate { ... }
1927 // this is allowed only if the prototype is an array
1928 if (pt.tag == ARRAY) {
1929 elemtype = types.elemtype(pt);
1930 } else {
1931 if (pt.tag != ERROR) {
1932 log.error(tree.pos(), "illegal.initializer.for.type",
1933 pt);
1934 }
1935 elemtype = types.createErrorType(pt);
1936 }
1937 }
1938 if (tree.elems != null) {
1939 attribExprs(tree.elems, env, elemtype);
1940 owntype = new ArrayType(elemtype, syms.arrayClass);
1941 }
1942 if (!types.isReifiable(elemtype))
1943 log.error(tree.pos(), "generic.array.creation");
1944 result = check(tree, owntype, VAL, pkind, pt);
1945 }
1947 public void visitParens(JCParens tree) {
1948 Type owntype = attribTree(tree.expr, env, pkind, pt);
1949 result = check(tree, owntype, pkind, pkind, pt);
1950 Symbol sym = TreeInfo.symbol(tree);
1951 if (sym != null && (sym.kind&(TYP|PCK)) != 0)
1952 log.error(tree.pos(), "illegal.start.of.type");
1953 }
1955 public void visitAssign(JCAssign tree) {
1956 Type owntype = attribTree(tree.lhs, env.dup(tree), VAR, Type.noType);
1957 Type capturedType = capture(owntype);
1958 attribExpr(tree.rhs, env, owntype);
1959 result = check(tree, capturedType, VAL, pkind, pt);
1960 }
1962 public void visitAssignop(JCAssignOp tree) {
1963 // Attribute arguments.
1964 Type owntype = attribTree(tree.lhs, env, VAR, Type.noType);
1965 Type operand = attribExpr(tree.rhs, env);
1966 // Find operator.
1967 Symbol operator = tree.operator = rs.resolveBinaryOperator(
1968 tree.pos(), tree.getTag() - JCTree.ASGOffset, env,
1969 owntype, operand);
1971 if (operator.kind == MTH &&
1972 !owntype.isErroneous() &&
1973 !operand.isErroneous()) {
1974 chk.checkOperator(tree.pos(),
1975 (OperatorSymbol)operator,
1976 tree.getTag() - JCTree.ASGOffset,
1977 owntype,
1978 operand);
1979 chk.checkDivZero(tree.rhs.pos(), operator, operand);
1980 chk.checkCastable(tree.rhs.pos(),
1981 operator.type.getReturnType(),
1982 owntype);
1983 }
1984 result = check(tree, owntype, VAL, pkind, pt);
1985 }
1987 public void visitUnary(JCUnary tree) {
1988 // Attribute arguments.
1989 Type argtype = (JCTree.PREINC <= tree.getTag() && tree.getTag() <= JCTree.POSTDEC)
1990 ? attribTree(tree.arg, env, VAR, Type.noType)
1991 : chk.checkNonVoid(tree.arg.pos(), attribExpr(tree.arg, env));
1993 // Find operator.
1994 Symbol operator = tree.operator =
1995 rs.resolveUnaryOperator(tree.pos(), tree.getTag(), env, argtype);
1997 Type owntype = types.createErrorType(tree.type);
1998 if (operator.kind == MTH &&
1999 !argtype.isErroneous()) {
2000 owntype = (JCTree.PREINC <= tree.getTag() && tree.getTag() <= JCTree.POSTDEC)
2001 ? tree.arg.type
2002 : operator.type.getReturnType();
2003 int opc = ((OperatorSymbol)operator).opcode;
2005 // If the argument is constant, fold it.
2006 if (argtype.constValue() != null) {
2007 Type ctype = cfolder.fold1(opc, argtype);
2008 if (ctype != null) {
2009 owntype = cfolder.coerce(ctype, owntype);
2011 // Remove constant types from arguments to
2012 // conserve space. The parser will fold concatenations
2013 // of string literals; the code here also
2014 // gets rid of intermediate results when some of the
2015 // operands are constant identifiers.
2016 if (tree.arg.type.tsym == syms.stringType.tsym) {
2017 tree.arg.type = syms.stringType;
2018 }
2019 }
2020 }
2021 }
2022 result = check(tree, owntype, VAL, pkind, pt);
2023 }
2025 public void visitBinary(JCBinary tree) {
2026 // Attribute arguments.
2027 Type left = chk.checkNonVoid(tree.lhs.pos(), attribExpr(tree.lhs, env));
2028 Type right = chk.checkNonVoid(tree.lhs.pos(), attribExpr(tree.rhs, env));
2030 // Find operator.
2031 Symbol operator = tree.operator =
2032 rs.resolveBinaryOperator(tree.pos(), tree.getTag(), env, left, right);
2034 Type owntype = types.createErrorType(tree.type);
2035 if (operator.kind == MTH &&
2036 !left.isErroneous() &&
2037 !right.isErroneous()) {
2038 owntype = operator.type.getReturnType();
2039 int opc = chk.checkOperator(tree.lhs.pos(),
2040 (OperatorSymbol)operator,
2041 tree.getTag(),
2042 left,
2043 right);
2045 // If both arguments are constants, fold them.
2046 if (left.constValue() != null && right.constValue() != null) {
2047 Type ctype = cfolder.fold2(opc, left, right);
2048 if (ctype != null) {
2049 owntype = cfolder.coerce(ctype, owntype);
2051 // Remove constant types from arguments to
2052 // conserve space. The parser will fold concatenations
2053 // of string literals; the code here also
2054 // gets rid of intermediate results when some of the
2055 // operands are constant identifiers.
2056 if (tree.lhs.type.tsym == syms.stringType.tsym) {
2057 tree.lhs.type = syms.stringType;
2058 }
2059 if (tree.rhs.type.tsym == syms.stringType.tsym) {
2060 tree.rhs.type = syms.stringType;
2061 }
2062 }
2063 }
2065 // Check that argument types of a reference ==, != are
2066 // castable to each other, (JLS???).
2067 if ((opc == ByteCodes.if_acmpeq || opc == ByteCodes.if_acmpne)) {
2068 if (!types.isCastable(left, right, new Warner(tree.pos()))) {
2069 log.error(tree.pos(), "incomparable.types", left, right);
2070 }
2071 }
2073 chk.checkDivZero(tree.rhs.pos(), operator, right);
2074 }
2075 result = check(tree, owntype, VAL, pkind, pt);
2076 }
2078 public void visitTypeCast(JCTypeCast tree) {
2079 Type clazztype = attribType(tree.clazz, env);
2080 chk.validate(tree.clazz, env, false);
2081 //a fresh environment is required for 292 inference to work properly ---
2082 //see Infer.instantiatePolymorphicSignatureInstance()
2083 Env<AttrContext> localEnv = env.dup(tree);
2084 Type exprtype = attribExpr(tree.expr, localEnv, Infer.anyPoly);
2085 Type owntype = chk.checkCastable(tree.expr.pos(), exprtype, clazztype);
2086 if (exprtype.constValue() != null)
2087 owntype = cfolder.coerce(exprtype, owntype);
2088 result = check(tree, capture(owntype), VAL, pkind, pt);
2089 }
2091 public void visitTypeTest(JCInstanceOf tree) {
2092 Type exprtype = chk.checkNullOrRefType(
2093 tree.expr.pos(), attribExpr(tree.expr, env));
2094 Type clazztype = chk.checkReifiableReferenceType(
2095 tree.clazz.pos(), attribType(tree.clazz, env));
2096 chk.validate(tree.clazz, env, false);
2097 chk.checkCastable(tree.expr.pos(), exprtype, clazztype);
2098 result = check(tree, syms.booleanType, VAL, pkind, pt);
2099 }
2101 public void visitIndexed(JCArrayAccess tree) {
2102 Type owntype = types.createErrorType(tree.type);
2103 Type atype = attribExpr(tree.indexed, env);
2104 attribExpr(tree.index, env, syms.intType);
2105 if (types.isArray(atype))
2106 owntype = types.elemtype(atype);
2107 else if (atype.tag != ERROR)
2108 log.error(tree.pos(), "array.req.but.found", atype);
2109 if ((pkind & VAR) == 0) owntype = capture(owntype);
2110 result = check(tree, owntype, VAR, pkind, pt);
2111 }
2113 public void visitIdent(JCIdent tree) {
2114 Symbol sym;
2115 boolean varArgs = false;
2117 // Find symbol
2118 if (pt.tag == METHOD || pt.tag == FORALL) {
2119 // If we are looking for a method, the prototype `pt' will be a
2120 // method type with the type of the call's arguments as parameters.
2121 env.info.varArgs = false;
2122 sym = rs.resolveMethod(tree.pos(), env, tree.name, pt.getParameterTypes(), pt.getTypeArguments());
2123 varArgs = env.info.varArgs;
2124 } else if (tree.sym != null && tree.sym.kind != VAR) {
2125 sym = tree.sym;
2126 } else {
2127 sym = rs.resolveIdent(tree.pos(), env, tree.name, pkind);
2128 }
2129 tree.sym = sym;
2131 // (1) Also find the environment current for the class where
2132 // sym is defined (`symEnv').
2133 // Only for pre-tiger versions (1.4 and earlier):
2134 // (2) Also determine whether we access symbol out of an anonymous
2135 // class in a this or super call. This is illegal for instance
2136 // members since such classes don't carry a this$n link.
2137 // (`noOuterThisPath').
2138 Env<AttrContext> symEnv = env;
2139 boolean noOuterThisPath = false;
2140 if (env.enclClass.sym.owner.kind != PCK && // we are in an inner class
2141 (sym.kind & (VAR | MTH | TYP)) != 0 &&
2142 sym.owner.kind == TYP &&
2143 tree.name != names._this && tree.name != names._super) {
2145 // Find environment in which identifier is defined.
2146 while (symEnv.outer != null &&
2147 !sym.isMemberOf(symEnv.enclClass.sym, types)) {
2148 if ((symEnv.enclClass.sym.flags() & NOOUTERTHIS) != 0)
2149 noOuterThisPath = !allowAnonOuterThis;
2150 symEnv = symEnv.outer;
2151 }
2152 }
2154 // If symbol is a variable, ...
2155 if (sym.kind == VAR) {
2156 VarSymbol v = (VarSymbol)sym;
2158 // ..., evaluate its initializer, if it has one, and check for
2159 // illegal forward reference.
2160 checkInit(tree, env, v, false);
2162 // If symbol is a local variable accessed from an embedded
2163 // inner class check that it is final.
2164 if (v.owner.kind == MTH &&
2165 v.owner != env.info.scope.owner &&
2166 (v.flags_field & FINAL) == 0) {
2167 log.error(tree.pos(),
2168 "local.var.accessed.from.icls.needs.final",
2169 v);
2170 }
2172 // If we are expecting a variable (as opposed to a value), check
2173 // that the variable is assignable in the current environment.
2174 if (pkind == VAR)
2175 checkAssignable(tree.pos(), v, null, env);
2176 }
2178 // In a constructor body,
2179 // if symbol is a field or instance method, check that it is
2180 // not accessed before the supertype constructor is called.
2181 if ((symEnv.info.isSelfCall || noOuterThisPath) &&
2182 (sym.kind & (VAR | MTH)) != 0 &&
2183 sym.owner.kind == TYP &&
2184 (sym.flags() & STATIC) == 0) {
2185 chk.earlyRefError(tree.pos(), sym.kind == VAR ? sym : thisSym(tree.pos(), env));
2186 }
2187 Env<AttrContext> env1 = env;
2188 if (sym.kind != ERR && sym.kind != TYP && sym.owner != null && sym.owner != env1.enclClass.sym) {
2189 // If the found symbol is inaccessible, then it is
2190 // accessed through an enclosing instance. Locate this
2191 // enclosing instance:
2192 while (env1.outer != null && !rs.isAccessible(env, env1.enclClass.sym.type, sym))
2193 env1 = env1.outer;
2194 }
2195 result = checkId(tree, env1.enclClass.sym.type, sym, env, pkind, pt, varArgs);
2196 }
2198 public void visitSelect(JCFieldAccess tree) {
2199 // Determine the expected kind of the qualifier expression.
2200 int skind = 0;
2201 if (tree.name == names._this || tree.name == names._super ||
2202 tree.name == names._class)
2203 {
2204 skind = TYP;
2205 } else {
2206 if ((pkind & PCK) != 0) skind = skind | PCK;
2207 if ((pkind & TYP) != 0) skind = skind | TYP | PCK;
2208 if ((pkind & (VAL | MTH)) != 0) skind = skind | VAL | TYP;
2209 }
2211 // Attribute the qualifier expression, and determine its symbol (if any).
2212 Type site = attribTree(tree.selected, env, skind, Infer.anyPoly);
2213 if ((pkind & (PCK | TYP)) == 0)
2214 site = capture(site); // Capture field access
2216 // don't allow T.class T[].class, etc
2217 if (skind == TYP) {
2218 Type elt = site;
2219 while (elt.tag == ARRAY)
2220 elt = ((ArrayType)elt).elemtype;
2221 if (elt.tag == TYPEVAR) {
2222 log.error(tree.pos(), "type.var.cant.be.deref");
2223 result = types.createErrorType(tree.type);
2224 return;
2225 }
2226 }
2228 // If qualifier symbol is a type or `super', assert `selectSuper'
2229 // for the selection. This is relevant for determining whether
2230 // protected symbols are accessible.
2231 Symbol sitesym = TreeInfo.symbol(tree.selected);
2232 boolean selectSuperPrev = env.info.selectSuper;
2233 env.info.selectSuper =
2234 sitesym != null &&
2235 sitesym.name == names._super;
2237 // If selected expression is polymorphic, strip
2238 // type parameters and remember in env.info.tvars, so that
2239 // they can be added later (in Attr.checkId and Infer.instantiateMethod).
2240 if (tree.selected.type.tag == FORALL) {
2241 ForAll pstype = (ForAll)tree.selected.type;
2242 env.info.tvars = pstype.tvars;
2243 site = tree.selected.type = pstype.qtype;
2244 }
2246 // Determine the symbol represented by the selection.
2247 env.info.varArgs = false;
2248 Symbol sym = selectSym(tree, sitesym, site, env, pt, pkind);
2249 if (sym.exists() && !isType(sym) && (pkind & (PCK | TYP)) != 0) {
2250 site = capture(site);
2251 sym = selectSym(tree, sitesym, site, env, pt, pkind);
2252 }
2253 boolean varArgs = env.info.varArgs;
2254 tree.sym = sym;
2256 if (site.tag == TYPEVAR && !isType(sym) && sym.kind != ERR) {
2257 while (site.tag == TYPEVAR) site = site.getUpperBound();
2258 site = capture(site);
2259 }
2261 // If that symbol is a variable, ...
2262 if (sym.kind == VAR) {
2263 VarSymbol v = (VarSymbol)sym;
2265 // ..., evaluate its initializer, if it has one, and check for
2266 // illegal forward reference.
2267 checkInit(tree, env, v, true);
2269 // If we are expecting a variable (as opposed to a value), check
2270 // that the variable is assignable in the current environment.
2271 if (pkind == VAR)
2272 checkAssignable(tree.pos(), v, tree.selected, env);
2273 }
2275 if (sitesym != null &&
2276 sitesym.kind == VAR &&
2277 ((VarSymbol)sitesym).isResourceVariable() &&
2278 sym.kind == MTH &&
2279 sym.overrides(syms.autoCloseableClose, sitesym.type.tsym, types, true) &&
2280 env.info.lint.isEnabled(LintCategory.TRY)) {
2281 log.warning(LintCategory.TRY, tree, "try.explicit.close.call");
2282 }
2284 // Disallow selecting a type from an expression
2285 if (isType(sym) && (sitesym==null || (sitesym.kind&(TYP|PCK)) == 0)) {
2286 tree.type = check(tree.selected, pt,
2287 sitesym == null ? VAL : sitesym.kind, TYP|PCK, pt);
2288 }
2290 if (isType(sitesym)) {
2291 if (sym.name == names._this) {
2292 // If `C' is the currently compiled class, check that
2293 // C.this' does not appear in a call to a super(...)
2294 if (env.info.isSelfCall &&
2295 site.tsym == env.enclClass.sym) {
2296 chk.earlyRefError(tree.pos(), sym);
2297 }
2298 } else {
2299 // Check if type-qualified fields or methods are static (JLS)
2300 if ((sym.flags() & STATIC) == 0 &&
2301 sym.name != names._super &&
2302 (sym.kind == VAR || sym.kind == MTH)) {
2303 rs.access(rs.new StaticError(sym),
2304 tree.pos(), site, sym.name, true);
2305 }
2306 }
2307 } else if (sym.kind != ERR && (sym.flags() & STATIC) != 0 && sym.name != names._class) {
2308 // If the qualified item is not a type and the selected item is static, report
2309 // a warning. Make allowance for the class of an array type e.g. Object[].class)
2310 chk.warnStatic(tree, "static.not.qualified.by.type", Kinds.kindName(sym.kind), sym.owner);
2311 }
2313 // If we are selecting an instance member via a `super', ...
2314 if (env.info.selectSuper && (sym.flags() & STATIC) == 0) {
2316 // Check that super-qualified symbols are not abstract (JLS)
2317 rs.checkNonAbstract(tree.pos(), sym);
2319 if (site.isRaw()) {
2320 // Determine argument types for site.
2321 Type site1 = types.asSuper(env.enclClass.sym.type, site.tsym);
2322 if (site1 != null) site = site1;
2323 }
2324 }
2326 env.info.selectSuper = selectSuperPrev;
2327 result = checkId(tree, site, sym, env, pkind, pt, varArgs);
2328 env.info.tvars = List.nil();
2329 }
2330 //where
2331 /** Determine symbol referenced by a Select expression,
2332 *
2333 * @param tree The select tree.
2334 * @param site The type of the selected expression,
2335 * @param env The current environment.
2336 * @param pt The current prototype.
2337 * @param pkind The expected kind(s) of the Select expression.
2338 */
2339 private Symbol selectSym(JCFieldAccess tree,
2340 Type site,
2341 Env<AttrContext> env,
2342 Type pt,
2343 int pkind) {
2344 return selectSym(tree, site.tsym, site, env, pt, pkind);
2345 }
2346 private Symbol selectSym(JCFieldAccess tree,
2347 Symbol location,
2348 Type site,
2349 Env<AttrContext> env,
2350 Type pt,
2351 int pkind) {
2352 DiagnosticPosition pos = tree.pos();
2353 Name name = tree.name;
2354 switch (site.tag) {
2355 case PACKAGE:
2356 return rs.access(
2357 rs.findIdentInPackage(env, site.tsym, name, pkind),
2358 pos, location, site, name, true);
2359 case ARRAY:
2360 case CLASS:
2361 if (pt.tag == METHOD || pt.tag == FORALL) {
2362 return rs.resolveQualifiedMethod(
2363 pos, env, location, site, name, pt.getParameterTypes(), pt.getTypeArguments());
2364 } else if (name == names._this || name == names._super) {
2365 return rs.resolveSelf(pos, env, site.tsym, name);
2366 } else if (name == names._class) {
2367 // In this case, we have already made sure in
2368 // visitSelect that qualifier expression is a type.
2369 Type t = syms.classType;
2370 List<Type> typeargs = allowGenerics
2371 ? List.of(types.erasure(site))
2372 : List.<Type>nil();
2373 t = new ClassType(t.getEnclosingType(), typeargs, t.tsym);
2374 return new VarSymbol(
2375 STATIC | PUBLIC | FINAL, names._class, t, site.tsym);
2376 } else {
2377 // We are seeing a plain identifier as selector.
2378 Symbol sym = rs.findIdentInType(env, site, name, pkind);
2379 if ((pkind & ERRONEOUS) == 0)
2380 sym = rs.access(sym, pos, location, site, name, true);
2381 return sym;
2382 }
2383 case WILDCARD:
2384 throw new AssertionError(tree);
2385 case TYPEVAR:
2386 // Normally, site.getUpperBound() shouldn't be null.
2387 // It should only happen during memberEnter/attribBase
2388 // when determining the super type which *must* beac
2389 // done before attributing the type variables. In
2390 // other words, we are seeing this illegal program:
2391 // class B<T> extends A<T.foo> {}
2392 Symbol sym = (site.getUpperBound() != null)
2393 ? selectSym(tree, location, capture(site.getUpperBound()), env, pt, pkind)
2394 : null;
2395 if (sym == null) {
2396 log.error(pos, "type.var.cant.be.deref");
2397 return syms.errSymbol;
2398 } else {
2399 Symbol sym2 = (sym.flags() & Flags.PRIVATE) != 0 ?
2400 rs.new AccessError(env, site, sym) :
2401 sym;
2402 rs.access(sym2, pos, location, site, name, true);
2403 return sym;
2404 }
2405 case ERROR:
2406 // preserve identifier names through errors
2407 return types.createErrorType(name, site.tsym, site).tsym;
2408 default:
2409 // The qualifier expression is of a primitive type -- only
2410 // .class is allowed for these.
2411 if (name == names._class) {
2412 // In this case, we have already made sure in Select that
2413 // qualifier expression is a type.
2414 Type t = syms.classType;
2415 Type arg = types.boxedClass(site).type;
2416 t = new ClassType(t.getEnclosingType(), List.of(arg), t.tsym);
2417 return new VarSymbol(
2418 STATIC | PUBLIC | FINAL, names._class, t, site.tsym);
2419 } else {
2420 log.error(pos, "cant.deref", site);
2421 return syms.errSymbol;
2422 }
2423 }
2424 }
2426 /** Determine type of identifier or select expression and check that
2427 * (1) the referenced symbol is not deprecated
2428 * (2) the symbol's type is safe (@see checkSafe)
2429 * (3) if symbol is a variable, check that its type and kind are
2430 * compatible with the prototype and protokind.
2431 * (4) if symbol is an instance field of a raw type,
2432 * which is being assigned to, issue an unchecked warning if its
2433 * type changes under erasure.
2434 * (5) if symbol is an instance method of a raw type, issue an
2435 * unchecked warning if its argument types change under erasure.
2436 * If checks succeed:
2437 * If symbol is a constant, return its constant type
2438 * else if symbol is a method, return its result type
2439 * otherwise return its type.
2440 * Otherwise return errType.
2441 *
2442 * @param tree The syntax tree representing the identifier
2443 * @param site If this is a select, the type of the selected
2444 * expression, otherwise the type of the current class.
2445 * @param sym The symbol representing the identifier.
2446 * @param env The current environment.
2447 * @param pkind The set of expected kinds.
2448 * @param pt The expected type.
2449 */
2450 Type checkId(JCTree tree,
2451 Type site,
2452 Symbol sym,
2453 Env<AttrContext> env,
2454 int pkind,
2455 Type pt,
2456 boolean useVarargs) {
2457 if (pt.isErroneous()) return types.createErrorType(site);
2458 Type owntype; // The computed type of this identifier occurrence.
2459 switch (sym.kind) {
2460 case TYP:
2461 // For types, the computed type equals the symbol's type,
2462 // except for two situations:
2463 owntype = sym.type;
2464 if (owntype.tag == CLASS) {
2465 Type ownOuter = owntype.getEnclosingType();
2467 // (a) If the symbol's type is parameterized, erase it
2468 // because no type parameters were given.
2469 // We recover generic outer type later in visitTypeApply.
2470 if (owntype.tsym.type.getTypeArguments().nonEmpty()) {
2471 owntype = types.erasure(owntype);
2472 }
2474 // (b) If the symbol's type is an inner class, then
2475 // we have to interpret its outer type as a superclass
2476 // of the site type. Example:
2477 //
2478 // class Tree<A> { class Visitor { ... } }
2479 // class PointTree extends Tree<Point> { ... }
2480 // ...PointTree.Visitor...
2481 //
2482 // Then the type of the last expression above is
2483 // Tree<Point>.Visitor.
2484 else if (ownOuter.tag == CLASS && site != ownOuter) {
2485 Type normOuter = site;
2486 if (normOuter.tag == CLASS)
2487 normOuter = types.asEnclosingSuper(site, ownOuter.tsym);
2488 if (normOuter == null) // perhaps from an import
2489 normOuter = types.erasure(ownOuter);
2490 if (normOuter != ownOuter)
2491 owntype = new ClassType(
2492 normOuter, List.<Type>nil(), owntype.tsym);
2493 }
2494 }
2495 break;
2496 case VAR:
2497 VarSymbol v = (VarSymbol)sym;
2498 // Test (4): if symbol is an instance field of a raw type,
2499 // which is being assigned to, issue an unchecked warning if
2500 // its type changes under erasure.
2501 if (allowGenerics &&
2502 pkind == VAR &&
2503 v.owner.kind == TYP &&
2504 (v.flags() & STATIC) == 0 &&
2505 (site.tag == CLASS || site.tag == TYPEVAR)) {
2506 Type s = types.asOuterSuper(site, v.owner);
2507 if (s != null &&
2508 s.isRaw() &&
2509 !types.isSameType(v.type, v.erasure(types))) {
2510 chk.warnUnchecked(tree.pos(),
2511 "unchecked.assign.to.var",
2512 v, s);
2513 }
2514 }
2515 // The computed type of a variable is the type of the
2516 // variable symbol, taken as a member of the site type.
2517 owntype = (sym.owner.kind == TYP &&
2518 sym.name != names._this && sym.name != names._super)
2519 ? types.memberType(site, sym)
2520 : sym.type;
2522 if (env.info.tvars.nonEmpty()) {
2523 Type owntype1 = new ForAll(env.info.tvars, owntype);
2524 for (List<Type> l = env.info.tvars; l.nonEmpty(); l = l.tail)
2525 if (!owntype.contains(l.head)) {
2526 log.error(tree.pos(), "undetermined.type", owntype1);
2527 owntype1 = types.createErrorType(owntype1);
2528 }
2529 owntype = owntype1;
2530 }
2532 // If the variable is a constant, record constant value in
2533 // computed type.
2534 if (v.getConstValue() != null && isStaticReference(tree))
2535 owntype = owntype.constType(v.getConstValue());
2537 if (pkind == VAL) {
2538 owntype = capture(owntype); // capture "names as expressions"
2539 }
2540 break;
2541 case MTH: {
2542 JCMethodInvocation app = (JCMethodInvocation)env.tree;
2543 owntype = checkMethod(site, sym, env, app.args,
2544 pt.getParameterTypes(), pt.getTypeArguments(),
2545 env.info.varArgs);
2546 break;
2547 }
2548 case PCK: case ERR:
2549 owntype = sym.type;
2550 break;
2551 default:
2552 throw new AssertionError("unexpected kind: " + sym.kind +
2553 " in tree " + tree);
2554 }
2556 // Test (1): emit a `deprecation' warning if symbol is deprecated.
2557 // (for constructors, the error was given when the constructor was
2558 // resolved)
2560 if (sym.name != names.init) {
2561 chk.checkDeprecated(tree.pos(), env.info.scope.owner, sym);
2562 chk.checkSunAPI(tree.pos(), sym);
2563 }
2565 // Test (3): if symbol is a variable, check that its type and
2566 // kind are compatible with the prototype and protokind.
2567 return check(tree, owntype, sym.kind, pkind, pt);
2568 }
2570 /** Check that variable is initialized and evaluate the variable's
2571 * initializer, if not yet done. Also check that variable is not
2572 * referenced before it is defined.
2573 * @param tree The tree making up the variable reference.
2574 * @param env The current environment.
2575 * @param v The variable's symbol.
2576 */
2577 private void checkInit(JCTree tree,
2578 Env<AttrContext> env,
2579 VarSymbol v,
2580 boolean onlyWarning) {
2581 // System.err.println(v + " " + ((v.flags() & STATIC) != 0) + " " +
2582 // tree.pos + " " + v.pos + " " +
2583 // Resolve.isStatic(env));//DEBUG
2585 // A forward reference is diagnosed if the declaration position
2586 // of the variable is greater than the current tree position
2587 // and the tree and variable definition occur in the same class
2588 // definition. Note that writes don't count as references.
2589 // This check applies only to class and instance
2590 // variables. Local variables follow different scope rules,
2591 // and are subject to definite assignment checking.
2592 if ((env.info.enclVar == v || v.pos > tree.pos) &&
2593 v.owner.kind == TYP &&
2594 canOwnInitializer(env.info.scope.owner) &&
2595 v.owner == env.info.scope.owner.enclClass() &&
2596 ((v.flags() & STATIC) != 0) == Resolve.isStatic(env) &&
2597 (env.tree.getTag() != JCTree.ASSIGN ||
2598 TreeInfo.skipParens(((JCAssign) env.tree).lhs) != tree)) {
2599 String suffix = (env.info.enclVar == v) ?
2600 "self.ref" : "forward.ref";
2601 if (!onlyWarning || isStaticEnumField(v)) {
2602 log.error(tree.pos(), "illegal." + suffix);
2603 } else if (useBeforeDeclarationWarning) {
2604 log.warning(tree.pos(), suffix, v);
2605 }
2606 }
2608 v.getConstValue(); // ensure initializer is evaluated
2610 checkEnumInitializer(tree, env, v);
2611 }
2613 /**
2614 * Check for illegal references to static members of enum. In
2615 * an enum type, constructors and initializers may not
2616 * reference its static members unless they are constant.
2617 *
2618 * @param tree The tree making up the variable reference.
2619 * @param env The current environment.
2620 * @param v The variable's symbol.
2621 * @see JLS 3rd Ed. (8.9 Enums)
2622 */
2623 private void checkEnumInitializer(JCTree tree, Env<AttrContext> env, VarSymbol v) {
2624 // JLS 3rd Ed.:
2625 //
2626 // "It is a compile-time error to reference a static field
2627 // of an enum type that is not a compile-time constant
2628 // (15.28) from constructors, instance initializer blocks,
2629 // or instance variable initializer expressions of that
2630 // type. It is a compile-time error for the constructors,
2631 // instance initializer blocks, or instance variable
2632 // initializer expressions of an enum constant e to refer
2633 // to itself or to an enum constant of the same type that
2634 // is declared to the right of e."
2635 if (isStaticEnumField(v)) {
2636 ClassSymbol enclClass = env.info.scope.owner.enclClass();
2638 if (enclClass == null || enclClass.owner == null)
2639 return;
2641 // See if the enclosing class is the enum (or a
2642 // subclass thereof) declaring v. If not, this
2643 // reference is OK.
2644 if (v.owner != enclClass && !types.isSubtype(enclClass.type, v.owner.type))
2645 return;
2647 // If the reference isn't from an initializer, then
2648 // the reference is OK.
2649 if (!Resolve.isInitializer(env))
2650 return;
2652 log.error(tree.pos(), "illegal.enum.static.ref");
2653 }
2654 }
2656 /** Is the given symbol a static, non-constant field of an Enum?
2657 * Note: enum literals should not be regarded as such
2658 */
2659 private boolean isStaticEnumField(VarSymbol v) {
2660 return Flags.isEnum(v.owner) &&
2661 Flags.isStatic(v) &&
2662 !Flags.isConstant(v) &&
2663 v.name != names._class;
2664 }
2666 /** Can the given symbol be the owner of code which forms part
2667 * if class initialization? This is the case if the symbol is
2668 * a type or field, or if the symbol is the synthetic method.
2669 * owning a block.
2670 */
2671 private boolean canOwnInitializer(Symbol sym) {
2672 return
2673 (sym.kind & (VAR | TYP)) != 0 ||
2674 (sym.kind == MTH && (sym.flags() & BLOCK) != 0);
2675 }
2677 Warner noteWarner = new Warner();
2679 /**
2680 * Check that method arguments conform to its instantation.
2681 **/
2682 public Type checkMethod(Type site,
2683 Symbol sym,
2684 Env<AttrContext> env,
2685 final List<JCExpression> argtrees,
2686 List<Type> argtypes,
2687 List<Type> typeargtypes,
2688 boolean useVarargs) {
2689 // Test (5): if symbol is an instance method of a raw type, issue
2690 // an unchecked warning if its argument types change under erasure.
2691 if (allowGenerics &&
2692 (sym.flags() & STATIC) == 0 &&
2693 (site.tag == CLASS || site.tag == TYPEVAR)) {
2694 Type s = types.asOuterSuper(site, sym.owner);
2695 if (s != null && s.isRaw() &&
2696 !types.isSameTypes(sym.type.getParameterTypes(),
2697 sym.erasure(types).getParameterTypes())) {
2698 chk.warnUnchecked(env.tree.pos(),
2699 "unchecked.call.mbr.of.raw.type",
2700 sym, s);
2701 }
2702 }
2704 // Compute the identifier's instantiated type.
2705 // For methods, we need to compute the instance type by
2706 // Resolve.instantiate from the symbol's type as well as
2707 // any type arguments and value arguments.
2708 noteWarner.clear();
2709 Type owntype = rs.instantiate(env,
2710 site,
2711 sym,
2712 argtypes,
2713 typeargtypes,
2714 true,
2715 useVarargs,
2716 noteWarner);
2717 boolean warned = noteWarner.hasNonSilentLint(LintCategory.UNCHECKED);
2719 // If this fails, something went wrong; we should not have
2720 // found the identifier in the first place.
2721 if (owntype == null) {
2722 if (!pt.isErroneous())
2723 log.error(env.tree.pos(),
2724 "internal.error.cant.instantiate",
2725 sym, site,
2726 Type.toString(pt.getParameterTypes()));
2727 owntype = types.createErrorType(site);
2728 } else {
2729 // System.out.println("call : " + env.tree);
2730 // System.out.println("method : " + owntype);
2731 // System.out.println("actuals: " + argtypes);
2732 List<Type> formals = owntype.getParameterTypes();
2733 Type last = useVarargs ? formals.last() : null;
2734 if (sym.name==names.init &&
2735 sym.owner == syms.enumSym)
2736 formals = formals.tail.tail;
2737 List<JCExpression> args = argtrees;
2738 while (formals.head != last) {
2739 JCTree arg = args.head;
2740 Warner warn = chk.convertWarner(arg.pos(), arg.type, formals.head);
2741 assertConvertible(arg, arg.type, formals.head, warn);
2742 warned |= warn.hasNonSilentLint(LintCategory.UNCHECKED);
2743 args = args.tail;
2744 formals = formals.tail;
2745 }
2746 if (useVarargs) {
2747 Type varArg = types.elemtype(last);
2748 while (args.tail != null) {
2749 JCTree arg = args.head;
2750 Warner warn = chk.convertWarner(arg.pos(), arg.type, varArg);
2751 assertConvertible(arg, arg.type, varArg, warn);
2752 warned |= warn.hasNonSilentLint(LintCategory.UNCHECKED);
2753 args = args.tail;
2754 }
2755 } else if ((sym.flags() & VARARGS) != 0 && allowVarargs) {
2756 // non-varargs call to varargs method
2757 Type varParam = owntype.getParameterTypes().last();
2758 Type lastArg = argtypes.last();
2759 if (types.isSubtypeUnchecked(lastArg, types.elemtype(varParam)) &&
2760 !types.isSameType(types.erasure(varParam), types.erasure(lastArg)))
2761 log.warning(argtrees.last().pos(), "inexact.non-varargs.call",
2762 types.elemtype(varParam),
2763 varParam);
2764 }
2766 if (warned && sym.type.tag == FORALL) {
2767 chk.warnUnchecked(env.tree.pos(),
2768 "unchecked.meth.invocation.applied",
2769 kindName(sym),
2770 sym.name,
2771 rs.methodArguments(sym.type.getParameterTypes()),
2772 rs.methodArguments(argtypes),
2773 kindName(sym.location()),
2774 sym.location());
2775 owntype = new MethodType(owntype.getParameterTypes(),
2776 types.erasure(owntype.getReturnType()),
2777 types.erasure(owntype.getThrownTypes()),
2778 syms.methodClass);
2779 }
2780 if (useVarargs) {
2781 JCTree tree = env.tree;
2782 Type argtype = owntype.getParameterTypes().last();
2783 if (owntype.getReturnType().tag != FORALL || warned) {
2784 chk.checkVararg(env.tree.pos(), owntype.getParameterTypes(), sym);
2785 }
2786 Type elemtype = types.elemtype(argtype);
2787 switch (tree.getTag()) {
2788 case JCTree.APPLY:
2789 ((JCMethodInvocation) tree).varargsElement = elemtype;
2790 break;
2791 case JCTree.NEWCLASS:
2792 ((JCNewClass) tree).varargsElement = elemtype;
2793 break;
2794 default:
2795 throw new AssertionError(""+tree);
2796 }
2797 }
2798 }
2799 return owntype;
2800 }
2802 private void assertConvertible(JCTree tree, Type actual, Type formal, Warner warn) {
2803 if (types.isConvertible(actual, formal, warn))
2804 return;
2806 if (formal.isCompound()
2807 && types.isSubtype(actual, types.supertype(formal))
2808 && types.isSubtypeUnchecked(actual, types.interfaces(formal), warn))
2809 return;
2811 if (false) {
2812 // TODO: make assertConvertible work
2813 chk.typeError(tree.pos(), diags.fragment("incompatible.types"), actual, formal);
2814 throw new AssertionError("Tree: " + tree
2815 + " actual:" + actual
2816 + " formal: " + formal);
2817 }
2818 }
2820 public void visitLiteral(JCLiteral tree) {
2821 result = check(
2822 tree, litType(tree.typetag).constType(tree.value), VAL, pkind, pt);
2823 }
2824 //where
2825 /** Return the type of a literal with given type tag.
2826 */
2827 Type litType(int tag) {
2828 return (tag == TypeTags.CLASS) ? syms.stringType : syms.typeOfTag[tag];
2829 }
2831 public void visitTypeIdent(JCPrimitiveTypeTree tree) {
2832 result = check(tree, syms.typeOfTag[tree.typetag], TYP, pkind, pt);
2833 }
2835 public void visitTypeArray(JCArrayTypeTree tree) {
2836 Type etype = attribType(tree.elemtype, env);
2837 Type type = new ArrayType(etype, syms.arrayClass);
2838 result = check(tree, type, TYP, pkind, pt);
2839 }
2841 /** Visitor method for parameterized types.
2842 * Bound checking is left until later, since types are attributed
2843 * before supertype structure is completely known
2844 */
2845 public void visitTypeApply(JCTypeApply tree) {
2846 Type owntype = types.createErrorType(tree.type);
2848 // Attribute functor part of application and make sure it's a class.
2849 Type clazztype = chk.checkClassType(tree.clazz.pos(), attribType(tree.clazz, env));
2851 // Attribute type parameters
2852 List<Type> actuals = attribTypes(tree.arguments, env);
2854 if (clazztype.tag == CLASS) {
2855 List<Type> formals = clazztype.tsym.type.getTypeArguments();
2857 if (actuals.length() == formals.length() || actuals.length() == 0) {
2858 List<Type> a = actuals;
2859 List<Type> f = formals;
2860 while (a.nonEmpty()) {
2861 a.head = a.head.withTypeVar(f.head);
2862 a = a.tail;
2863 f = f.tail;
2864 }
2865 // Compute the proper generic outer
2866 Type clazzOuter = clazztype.getEnclosingType();
2867 if (clazzOuter.tag == CLASS) {
2868 Type site;
2869 JCExpression clazz = TreeInfo.typeIn(tree.clazz);
2870 if (clazz.getTag() == JCTree.IDENT) {
2871 site = env.enclClass.sym.type;
2872 } else if (clazz.getTag() == JCTree.SELECT) {
2873 site = ((JCFieldAccess) clazz).selected.type;
2874 } else throw new AssertionError(""+tree);
2875 if (clazzOuter.tag == CLASS && site != clazzOuter) {
2876 if (site.tag == CLASS)
2877 site = types.asOuterSuper(site, clazzOuter.tsym);
2878 if (site == null)
2879 site = types.erasure(clazzOuter);
2880 clazzOuter = site;
2881 }
2882 }
2883 owntype = new ClassType(clazzOuter, actuals, clazztype.tsym);
2884 } else {
2885 if (formals.length() != 0) {
2886 log.error(tree.pos(), "wrong.number.type.args",
2887 Integer.toString(formals.length()));
2888 } else {
2889 log.error(tree.pos(), "type.doesnt.take.params", clazztype.tsym);
2890 }
2891 owntype = types.createErrorType(tree.type);
2892 }
2893 }
2894 result = check(tree, owntype, TYP, pkind, pt);
2895 }
2897 public void visitTypeDisjunction(JCTypeDisjunction tree) {
2898 ListBuffer<Type> multicatchTypes = ListBuffer.lb();
2899 for (JCExpression typeTree : tree.alternatives) {
2900 Type ctype = attribType(typeTree, env);
2901 ctype = chk.checkType(typeTree.pos(),
2902 chk.checkClassType(typeTree.pos(), ctype),
2903 syms.throwableType);
2904 multicatchTypes.append(ctype);
2905 }
2906 tree.type = result = check(tree, types.lub(multicatchTypes.toList()), TYP, pkind, pt);
2907 }
2909 public void visitTypeParameter(JCTypeParameter tree) {
2910 TypeVar a = (TypeVar)tree.type;
2911 Set<Type> boundSet = new HashSet<Type>();
2912 if (a.bound.isErroneous())
2913 return;
2914 List<Type> bs = types.getBounds(a);
2915 if (tree.bounds.nonEmpty()) {
2916 // accept class or interface or typevar as first bound.
2917 Type b = checkBase(bs.head, tree.bounds.head, env, false, false, false);
2918 boundSet.add(types.erasure(b));
2919 if (b.isErroneous()) {
2920 a.bound = b;
2921 }
2922 else if (b.tag == TYPEVAR) {
2923 // if first bound was a typevar, do not accept further bounds.
2924 if (tree.bounds.tail.nonEmpty()) {
2925 log.error(tree.bounds.tail.head.pos(),
2926 "type.var.may.not.be.followed.by.other.bounds");
2927 tree.bounds = List.of(tree.bounds.head);
2928 a.bound = bs.head;
2929 }
2930 } else {
2931 // if first bound was a class or interface, accept only interfaces
2932 // as further bounds.
2933 for (JCExpression bound : tree.bounds.tail) {
2934 bs = bs.tail;
2935 Type i = checkBase(bs.head, bound, env, false, true, false);
2936 if (i.isErroneous())
2937 a.bound = i;
2938 else if (i.tag == CLASS)
2939 chk.checkNotRepeated(bound.pos(), types.erasure(i), boundSet);
2940 }
2941 }
2942 }
2943 bs = types.getBounds(a);
2945 // in case of multiple bounds ...
2946 if (bs.length() > 1) {
2947 // ... the variable's bound is a class type flagged COMPOUND
2948 // (see comment for TypeVar.bound).
2949 // In this case, generate a class tree that represents the
2950 // bound class, ...
2951 JCExpression extending;
2952 List<JCExpression> implementing;
2953 if ((bs.head.tsym.flags() & INTERFACE) == 0) {
2954 extending = tree.bounds.head;
2955 implementing = tree.bounds.tail;
2956 } else {
2957 extending = null;
2958 implementing = tree.bounds;
2959 }
2960 JCClassDecl cd = make.at(tree.pos).ClassDef(
2961 make.Modifiers(PUBLIC | ABSTRACT),
2962 tree.name, List.<JCTypeParameter>nil(),
2963 extending, implementing, List.<JCTree>nil());
2965 ClassSymbol c = (ClassSymbol)a.getUpperBound().tsym;
2966 Assert.check((c.flags() & COMPOUND) != 0);
2967 cd.sym = c;
2968 c.sourcefile = env.toplevel.sourcefile;
2970 // ... and attribute the bound class
2971 c.flags_field |= UNATTRIBUTED;
2972 Env<AttrContext> cenv = enter.classEnv(cd, env);
2973 enter.typeEnvs.put(c, cenv);
2974 }
2975 }
2978 public void visitWildcard(JCWildcard tree) {
2979 //- System.err.println("visitWildcard("+tree+");");//DEBUG
2980 Type type = (tree.kind.kind == BoundKind.UNBOUND)
2981 ? syms.objectType
2982 : attribType(tree.inner, env);
2983 result = check(tree, new WildcardType(chk.checkRefType(tree.pos(), type),
2984 tree.kind.kind,
2985 syms.boundClass),
2986 TYP, pkind, pt);
2987 }
2989 public void visitAnnotation(JCAnnotation tree) {
2990 log.error(tree.pos(), "annotation.not.valid.for.type", pt);
2991 result = tree.type = syms.errType;
2992 }
2994 public void visitErroneous(JCErroneous tree) {
2995 if (tree.errs != null)
2996 for (JCTree err : tree.errs)
2997 attribTree(err, env, ERR, pt);
2998 result = tree.type = syms.errType;
2999 }
3001 /** Default visitor method for all other trees.
3002 */
3003 public void visitTree(JCTree tree) {
3004 throw new AssertionError();
3005 }
3007 /** Main method: attribute class definition associated with given class symbol.
3008 * reporting completion failures at the given position.
3009 * @param pos The source position at which completion errors are to be
3010 * reported.
3011 * @param c The class symbol whose definition will be attributed.
3012 */
3013 public void attribClass(DiagnosticPosition pos, ClassSymbol c) {
3014 try {
3015 annotate.flush();
3016 attribClass(c);
3017 } catch (CompletionFailure ex) {
3018 chk.completionError(pos, ex);
3019 }
3020 }
3022 /** Attribute class definition associated with given class symbol.
3023 * @param c The class symbol whose definition will be attributed.
3024 */
3025 void attribClass(ClassSymbol c) throws CompletionFailure {
3026 if (c.type.tag == ERROR) return;
3028 // Check for cycles in the inheritance graph, which can arise from
3029 // ill-formed class files.
3030 chk.checkNonCyclic(null, c.type);
3032 Type st = types.supertype(c.type);
3033 if ((c.flags_field & Flags.COMPOUND) == 0) {
3034 // First, attribute superclass.
3035 if (st.tag == CLASS)
3036 attribClass((ClassSymbol)st.tsym);
3038 // Next attribute owner, if it is a class.
3039 if (c.owner.kind == TYP && c.owner.type.tag == CLASS)
3040 attribClass((ClassSymbol)c.owner);
3041 }
3043 // The previous operations might have attributed the current class
3044 // if there was a cycle. So we test first whether the class is still
3045 // UNATTRIBUTED.
3046 if ((c.flags_field & UNATTRIBUTED) != 0) {
3047 c.flags_field &= ~UNATTRIBUTED;
3049 // Get environment current at the point of class definition.
3050 Env<AttrContext> env = enter.typeEnvs.get(c);
3052 // The info.lint field in the envs stored in enter.typeEnvs is deliberately uninitialized,
3053 // because the annotations were not available at the time the env was created. Therefore,
3054 // we look up the environment chain for the first enclosing environment for which the
3055 // lint value is set. Typically, this is the parent env, but might be further if there
3056 // are any envs created as a result of TypeParameter nodes.
3057 Env<AttrContext> lintEnv = env;
3058 while (lintEnv.info.lint == null)
3059 lintEnv = lintEnv.next;
3061 // Having found the enclosing lint value, we can initialize the lint value for this class
3062 env.info.lint = lintEnv.info.lint.augment(c.attributes_field, c.flags());
3064 Lint prevLint = chk.setLint(env.info.lint);
3065 JavaFileObject prev = log.useSource(c.sourcefile);
3067 try {
3068 // java.lang.Enum may not be subclassed by a non-enum
3069 if (st.tsym == syms.enumSym &&
3070 ((c.flags_field & (Flags.ENUM|Flags.COMPOUND)) == 0))
3071 log.error(env.tree.pos(), "enum.no.subclassing");
3073 // Enums may not be extended by source-level classes
3074 if (st.tsym != null &&
3075 ((st.tsym.flags_field & Flags.ENUM) != 0) &&
3076 ((c.flags_field & (Flags.ENUM | Flags.COMPOUND)) == 0) &&
3077 !target.compilerBootstrap(c)) {
3078 log.error(env.tree.pos(), "enum.types.not.extensible");
3079 }
3080 attribClassBody(env, c);
3082 chk.checkDeprecatedAnnotation(env.tree.pos(), c);
3083 } finally {
3084 log.useSource(prev);
3085 chk.setLint(prevLint);
3086 }
3088 }
3089 }
3091 public void visitImport(JCImport tree) {
3092 // nothing to do
3093 }
3095 /** Finish the attribution of a class. */
3096 private void attribClassBody(Env<AttrContext> env, ClassSymbol c) {
3097 JCClassDecl tree = (JCClassDecl)env.tree;
3098 Assert.check(c == tree.sym);
3100 // Validate annotations
3101 chk.validateAnnotations(tree.mods.annotations, c);
3103 // Validate type parameters, supertype and interfaces.
3104 attribBounds(tree.typarams);
3105 if (!c.isAnonymous()) {
3106 //already checked if anonymous
3107 chk.validate(tree.typarams, env);
3108 chk.validate(tree.extending, env);
3109 chk.validate(tree.implementing, env);
3110 }
3112 // If this is a non-abstract class, check that it has no abstract
3113 // methods or unimplemented methods of an implemented interface.
3114 if ((c.flags() & (ABSTRACT | INTERFACE)) == 0) {
3115 if (!relax)
3116 chk.checkAllDefined(tree.pos(), c);
3117 }
3119 if ((c.flags() & ANNOTATION) != 0) {
3120 if (tree.implementing.nonEmpty())
3121 log.error(tree.implementing.head.pos(),
3122 "cant.extend.intf.annotation");
3123 if (tree.typarams.nonEmpty())
3124 log.error(tree.typarams.head.pos(),
3125 "intf.annotation.cant.have.type.params");
3126 } else {
3127 // Check that all extended classes and interfaces
3128 // are compatible (i.e. no two define methods with same arguments
3129 // yet different return types). (JLS 8.4.6.3)
3130 chk.checkCompatibleSupertypes(tree.pos(), c.type);
3131 }
3133 // Check that class does not import the same parameterized interface
3134 // with two different argument lists.
3135 chk.checkClassBounds(tree.pos(), c.type);
3137 tree.type = c.type;
3139 for (List<JCTypeParameter> l = tree.typarams;
3140 l.nonEmpty(); l = l.tail) {
3141 Assert.checkNonNull(env.info.scope.lookup(l.head.name).scope);
3142 }
3144 // Check that a generic class doesn't extend Throwable
3145 if (!c.type.allparams().isEmpty() && types.isSubtype(c.type, syms.throwableType))
3146 log.error(tree.extending.pos(), "generic.throwable");
3148 // Check that all methods which implement some
3149 // method conform to the method they implement.
3150 chk.checkImplementations(tree);
3152 for (List<JCTree> l = tree.defs; l.nonEmpty(); l = l.tail) {
3153 // Attribute declaration
3154 attribStat(l.head, env);
3155 // Check that declarations in inner classes are not static (JLS 8.1.2)
3156 // Make an exception for static constants.
3157 if (c.owner.kind != PCK &&
3158 ((c.flags() & STATIC) == 0 || c.name == names.empty) &&
3159 (TreeInfo.flags(l.head) & (STATIC | INTERFACE)) != 0) {
3160 Symbol sym = null;
3161 if (l.head.getTag() == JCTree.VARDEF) sym = ((JCVariableDecl) l.head).sym;
3162 if (sym == null ||
3163 sym.kind != VAR ||
3164 ((VarSymbol) sym).getConstValue() == null)
3165 log.error(l.head.pos(), "icls.cant.have.static.decl", c);
3166 }
3167 }
3169 // Check for cycles among non-initial constructors.
3170 chk.checkCyclicConstructors(tree);
3172 // Check for cycles among annotation elements.
3173 chk.checkNonCyclicElements(tree);
3175 // Check for proper use of serialVersionUID
3176 if (env.info.lint.isEnabled(LintCategory.SERIAL) &&
3177 isSerializable(c) &&
3178 (c.flags() & Flags.ENUM) == 0 &&
3179 (c.flags() & ABSTRACT) == 0) {
3180 checkSerialVersionUID(tree, c);
3181 }
3182 }
3183 // where
3184 /** check if a class is a subtype of Serializable, if that is available. */
3185 private boolean isSerializable(ClassSymbol c) {
3186 try {
3187 syms.serializableType.complete();
3188 }
3189 catch (CompletionFailure e) {
3190 return false;
3191 }
3192 return types.isSubtype(c.type, syms.serializableType);
3193 }
3195 /** Check that an appropriate serialVersionUID member is defined. */
3196 private void checkSerialVersionUID(JCClassDecl tree, ClassSymbol c) {
3198 // check for presence of serialVersionUID
3199 Scope.Entry e = c.members().lookup(names.serialVersionUID);
3200 while (e.scope != null && e.sym.kind != VAR) e = e.next();
3201 if (e.scope == null) {
3202 log.warning(LintCategory.SERIAL,
3203 tree.pos(), "missing.SVUID", c);
3204 return;
3205 }
3207 // check that it is static final
3208 VarSymbol svuid = (VarSymbol)e.sym;
3209 if ((svuid.flags() & (STATIC | FINAL)) !=
3210 (STATIC | FINAL))
3211 log.warning(LintCategory.SERIAL,
3212 TreeInfo.diagnosticPositionFor(svuid, tree), "improper.SVUID", c);
3214 // check that it is long
3215 else if (svuid.type.tag != TypeTags.LONG)
3216 log.warning(LintCategory.SERIAL,
3217 TreeInfo.diagnosticPositionFor(svuid, tree), "long.SVUID", c);
3219 // check constant
3220 else if (svuid.getConstValue() == null)
3221 log.warning(LintCategory.SERIAL,
3222 TreeInfo.diagnosticPositionFor(svuid, tree), "constant.SVUID", c);
3223 }
3225 private Type capture(Type type) {
3226 return types.capture(type);
3227 }
3229 // <editor-fold desc="post-attribution visitor">
3231 /**
3232 * Handle missing types/symbols in an AST. This routine is useful when
3233 * the compiler has encountered some errors (which might have ended up
3234 * terminating attribution abruptly); if the compiler is used in fail-over
3235 * mode (e.g. by an IDE) and the AST contains semantic errors, this routine
3236 * prevents NPE to be progagated during subsequent compilation steps.
3237 */
3238 public void postAttr(Env<AttrContext> env) {
3239 new PostAttrAnalyzer().scan(env.tree);
3240 }
3242 class PostAttrAnalyzer extends TreeScanner {
3244 private void initTypeIfNeeded(JCTree that) {
3245 if (that.type == null) {
3246 that.type = syms.unknownType;
3247 }
3248 }
3250 @Override
3251 public void scan(JCTree tree) {
3252 if (tree == null) return;
3253 if (tree instanceof JCExpression) {
3254 initTypeIfNeeded(tree);
3255 }
3256 super.scan(tree);
3257 }
3259 @Override
3260 public void visitIdent(JCIdent that) {
3261 if (that.sym == null) {
3262 that.sym = syms.unknownSymbol;
3263 }
3264 }
3266 @Override
3267 public void visitSelect(JCFieldAccess that) {
3268 if (that.sym == null) {
3269 that.sym = syms.unknownSymbol;
3270 }
3271 super.visitSelect(that);
3272 }
3274 @Override
3275 public void visitClassDef(JCClassDecl that) {
3276 initTypeIfNeeded(that);
3277 if (that.sym == null) {
3278 that.sym = new ClassSymbol(0, that.name, that.type, syms.noSymbol);
3279 }
3280 super.visitClassDef(that);
3281 }
3283 @Override
3284 public void visitMethodDef(JCMethodDecl that) {
3285 initTypeIfNeeded(that);
3286 if (that.sym == null) {
3287 that.sym = new MethodSymbol(0, that.name, that.type, syms.noSymbol);
3288 }
3289 super.visitMethodDef(that);
3290 }
3292 @Override
3293 public void visitVarDef(JCVariableDecl that) {
3294 initTypeIfNeeded(that);
3295 if (that.sym == null) {
3296 that.sym = new VarSymbol(0, that.name, that.type, syms.noSymbol);
3297 that.sym.adr = 0;
3298 }
3299 super.visitVarDef(that);
3300 }
3302 @Override
3303 public void visitNewClass(JCNewClass that) {
3304 if (that.constructor == null) {
3305 that.constructor = new MethodSymbol(0, names.init, syms.unknownType, syms.noSymbol);
3306 }
3307 if (that.constructorType == null) {
3308 that.constructorType = syms.unknownType;
3309 }
3310 super.visitNewClass(that);
3311 }
3313 @Override
3314 public void visitBinary(JCBinary that) {
3315 if (that.operator == null)
3316 that.operator = new OperatorSymbol(names.empty, syms.unknownType, -1, syms.noSymbol);
3317 super.visitBinary(that);
3318 }
3320 @Override
3321 public void visitUnary(JCUnary that) {
3322 if (that.operator == null)
3323 that.operator = new OperatorSymbol(names.empty, syms.unknownType, -1, syms.noSymbol);
3324 super.visitUnary(that);
3325 }
3326 }
3327 // </editor-fold>
3328 }