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src/share/classes/com/sun/tools/javac/comp/Attr.java@df371fd16386
src/share/classes/com/sun/tools/javac/comp/Attr.java
Wed, 26 Jan 2011 11:20:19 -0800
- author
- jjg
- date
- Wed, 26 Jan 2011 11:20:19 -0800
- changeset 841
- df371fd16386
- parent 830
- 02e6e7dd1a64
- child 852
- 899f7c3d9426
- permissions
- -rw-r--r--
6554097: "final" confuses @SuppressWarnings
Reviewed-by: mcimadamore
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;
87 public static Attr instance(Context context) {
88 Attr instance = context.get(attrKey);
89 if (instance == null)
90 instance = new Attr(context);
91 return instance;
92 }
94 protected Attr(Context context) {
95 context.put(attrKey, this);
97 names = Names.instance(context);
98 log = Log.instance(context);
99 syms = Symtab.instance(context);
100 rs = Resolve.instance(context);
101 chk = Check.instance(context);
102 memberEnter = MemberEnter.instance(context);
103 make = TreeMaker.instance(context);
104 enter = Enter.instance(context);
105 infer = Infer.instance(context);
106 cfolder = ConstFold.instance(context);
107 target = Target.instance(context);
108 types = Types.instance(context);
109 diags = JCDiagnostic.Factory.instance(context);
110 annotate = Annotate.instance(context);
112 Options options = Options.instance(context);
114 Source source = Source.instance(context);
115 allowGenerics = source.allowGenerics();
116 allowVarargs = source.allowVarargs();
117 allowEnums = source.allowEnums();
118 allowBoxing = source.allowBoxing();
119 allowCovariantReturns = source.allowCovariantReturns();
120 allowAnonOuterThis = source.allowAnonOuterThis();
121 allowStringsInSwitch = source.allowStringsInSwitch();
122 sourceName = source.name;
123 relax = (options.isSet("-retrofit") ||
124 options.isSet("-relax"));
125 findDiamonds = options.get("findDiamond") != null &&
126 source.allowDiamond();
127 useBeforeDeclarationWarning = options.isSet("useBeforeDeclarationWarning");
128 enableSunApiLintControl = options.isSet("enableSunApiLintControl");
129 }
131 /** Switch: relax some constraints for retrofit mode.
132 */
133 boolean relax;
135 /** Switch: support generics?
136 */
137 boolean allowGenerics;
139 /** Switch: allow variable-arity methods.
140 */
141 boolean allowVarargs;
143 /** Switch: support enums?
144 */
145 boolean allowEnums;
147 /** Switch: support boxing and unboxing?
148 */
149 boolean allowBoxing;
151 /** Switch: support covariant result types?
152 */
153 boolean allowCovariantReturns;
155 /** Switch: allow references to surrounding object from anonymous
156 * objects during constructor call?
157 */
158 boolean allowAnonOuterThis;
160 /** Switch: generates a warning if diamond can be safely applied
161 * to a given new expression
162 */
163 boolean findDiamonds;
165 /**
166 * Internally enables/disables diamond finder feature
167 */
168 static final boolean allowDiamondFinder = true;
170 /**
171 * Switch: warn about use of variable before declaration?
172 * RFE: 6425594
173 */
174 boolean useBeforeDeclarationWarning;
176 /**
177 * Switch: allow lint infrastructure to control proprietary
178 * API warnings.
179 */
180 boolean enableSunApiLintControl;
182 /**
183 * Switch: allow strings in switch?
184 */
185 boolean allowStringsInSwitch;
187 /**
188 * Switch: name of source level; used for error reporting.
189 */
190 String sourceName;
192 /** Check kind and type of given tree against protokind and prototype.
193 * If check succeeds, store type in tree and return it.
194 * If check fails, store errType in tree and return it.
195 * No checks are performed if the prototype is a method type.
196 * It is not necessary in this case since we know that kind and type
197 * are correct.
198 *
199 * @param tree The tree whose kind and type is checked
200 * @param owntype The computed type of the tree
201 * @param ownkind The computed kind of the tree
202 * @param pkind The expected kind (or: protokind) of the tree
203 * @param pt The expected type (or: prototype) of the tree
204 */
205 Type check(JCTree tree, Type owntype, int ownkind, int pkind, Type pt) {
206 if (owntype.tag != ERROR && pt.tag != METHOD && pt.tag != FORALL) {
207 if ((ownkind & ~pkind) == 0) {
208 owntype = chk.checkType(tree.pos(), owntype, pt, errKey);
209 } else {
210 log.error(tree.pos(), "unexpected.type",
211 kindNames(pkind),
212 kindName(ownkind));
213 owntype = types.createErrorType(owntype);
214 }
215 }
216 tree.type = owntype;
217 return owntype;
218 }
220 /** Is given blank final variable assignable, i.e. in a scope where it
221 * may be assigned to even though it is final?
222 * @param v The blank final variable.
223 * @param env The current environment.
224 */
225 boolean isAssignableAsBlankFinal(VarSymbol v, Env<AttrContext> env) {
226 Symbol owner = env.info.scope.owner;
227 // owner refers to the innermost variable, method or
228 // initializer block declaration at this point.
229 return
230 v.owner == owner
231 ||
232 ((owner.name == names.init || // i.e. we are in a constructor
233 owner.kind == VAR || // i.e. we are in a variable initializer
234 (owner.flags() & BLOCK) != 0) // i.e. we are in an initializer block
235 &&
236 v.owner == owner.owner
237 &&
238 ((v.flags() & STATIC) != 0) == Resolve.isStatic(env));
239 }
241 /** Check that variable can be assigned to.
242 * @param pos The current source code position.
243 * @param v The assigned varaible
244 * @param base If the variable is referred to in a Select, the part
245 * to the left of the `.', null otherwise.
246 * @param env The current environment.
247 */
248 void checkAssignable(DiagnosticPosition pos, VarSymbol v, JCTree base, Env<AttrContext> env) {
249 if ((v.flags() & FINAL) != 0 &&
250 ((v.flags() & HASINIT) != 0
251 ||
252 !((base == null ||
253 (base.getTag() == JCTree.IDENT && TreeInfo.name(base) == names._this)) &&
254 isAssignableAsBlankFinal(v, env)))) {
255 if (v.isResourceVariable()) { //TWR resource
256 log.error(pos, "try.resource.may.not.be.assigned", v);
257 } else {
258 log.error(pos, "cant.assign.val.to.final.var", v);
259 }
260 } else if ((v.flags() & EFFECTIVELY_FINAL) != 0) {
261 v.flags_field &= ~EFFECTIVELY_FINAL;
262 }
263 }
265 /** Does tree represent a static reference to an identifier?
266 * It is assumed that tree is either a SELECT or an IDENT.
267 * We have to weed out selects from non-type names here.
268 * @param tree The candidate tree.
269 */
270 boolean isStaticReference(JCTree tree) {
271 if (tree.getTag() == JCTree.SELECT) {
272 Symbol lsym = TreeInfo.symbol(((JCFieldAccess) tree).selected);
273 if (lsym == null || lsym.kind != TYP) {
274 return false;
275 }
276 }
277 return true;
278 }
280 /** Is this symbol a type?
281 */
282 static boolean isType(Symbol sym) {
283 return sym != null && sym.kind == TYP;
284 }
286 /** The current `this' symbol.
287 * @param env The current environment.
288 */
289 Symbol thisSym(DiagnosticPosition pos, Env<AttrContext> env) {
290 return rs.resolveSelf(pos, env, env.enclClass.sym, names._this);
291 }
293 /** Attribute a parsed identifier.
294 * @param tree Parsed identifier name
295 * @param topLevel The toplevel to use
296 */
297 public Symbol attribIdent(JCTree tree, JCCompilationUnit topLevel) {
298 Env<AttrContext> localEnv = enter.topLevelEnv(topLevel);
299 localEnv.enclClass = make.ClassDef(make.Modifiers(0),
300 syms.errSymbol.name,
301 null, null, null, null);
302 localEnv.enclClass.sym = syms.errSymbol;
303 return tree.accept(identAttributer, localEnv);
304 }
305 // where
306 private TreeVisitor<Symbol,Env<AttrContext>> identAttributer = new IdentAttributer();
307 private class IdentAttributer extends SimpleTreeVisitor<Symbol,Env<AttrContext>> {
308 @Override
309 public Symbol visitMemberSelect(MemberSelectTree node, Env<AttrContext> env) {
310 Symbol site = visit(node.getExpression(), env);
311 if (site.kind == ERR)
312 return site;
313 Name name = (Name)node.getIdentifier();
314 if (site.kind == PCK) {
315 env.toplevel.packge = (PackageSymbol)site;
316 return rs.findIdentInPackage(env, (TypeSymbol)site, name, TYP | PCK);
317 } else {
318 env.enclClass.sym = (ClassSymbol)site;
319 return rs.findMemberType(env, site.asType(), name, (TypeSymbol)site);
320 }
321 }
323 @Override
324 public Symbol visitIdentifier(IdentifierTree node, Env<AttrContext> env) {
325 return rs.findIdent(env, (Name)node.getName(), TYP | PCK);
326 }
327 }
329 public Type coerce(Type etype, Type ttype) {
330 return cfolder.coerce(etype, ttype);
331 }
333 public Type attribType(JCTree node, TypeSymbol sym) {
334 Env<AttrContext> env = enter.typeEnvs.get(sym);
335 Env<AttrContext> localEnv = env.dup(node, env.info.dup());
336 return attribTree(node, localEnv, Kinds.TYP, Type.noType);
337 }
339 public Env<AttrContext> attribExprToTree(JCTree expr, Env<AttrContext> env, JCTree tree) {
340 breakTree = tree;
341 JavaFileObject prev = log.useSource(env.toplevel.sourcefile);
342 try {
343 attribExpr(expr, env);
344 } catch (BreakAttr b) {
345 return b.env;
346 } catch (AssertionError ae) {
347 if (ae.getCause() instanceof BreakAttr) {
348 return ((BreakAttr)(ae.getCause())).env;
349 } else {
350 throw ae;
351 }
352 } finally {
353 breakTree = null;
354 log.useSource(prev);
355 }
356 return env;
357 }
359 public Env<AttrContext> attribStatToTree(JCTree stmt, Env<AttrContext> env, JCTree tree) {
360 breakTree = tree;
361 JavaFileObject prev = log.useSource(env.toplevel.sourcefile);
362 try {
363 attribStat(stmt, env);
364 } catch (BreakAttr b) {
365 return b.env;
366 } catch (AssertionError ae) {
367 if (ae.getCause() instanceof BreakAttr) {
368 return ((BreakAttr)(ae.getCause())).env;
369 } else {
370 throw ae;
371 }
372 } finally {
373 breakTree = null;
374 log.useSource(prev);
375 }
376 return env;
377 }
379 private JCTree breakTree = null;
381 private static class BreakAttr extends RuntimeException {
382 static final long serialVersionUID = -6924771130405446405L;
383 private Env<AttrContext> env;
384 private BreakAttr(Env<AttrContext> env) {
385 this.env = env;
386 }
387 }
390 /* ************************************************************************
391 * Visitor methods
392 *************************************************************************/
394 /** Visitor argument: the current environment.
395 */
396 Env<AttrContext> env;
398 /** Visitor argument: the currently expected proto-kind.
399 */
400 int pkind;
402 /** Visitor argument: the currently expected proto-type.
403 */
404 Type pt;
406 /** Visitor argument: the error key to be generated when a type error occurs
407 */
408 String errKey;
410 /** Visitor result: the computed type.
411 */
412 Type result;
414 /** Visitor method: attribute a tree, catching any completion failure
415 * exceptions. Return the tree's type.
416 *
417 * @param tree The tree to be visited.
418 * @param env The environment visitor argument.
419 * @param pkind The protokind visitor argument.
420 * @param pt The prototype visitor argument.
421 */
422 Type attribTree(JCTree tree, Env<AttrContext> env, int pkind, Type pt) {
423 return attribTree(tree, env, pkind, pt, "incompatible.types");
424 }
426 Type attribTree(JCTree tree, Env<AttrContext> env, int pkind, Type pt, String errKey) {
427 Env<AttrContext> prevEnv = this.env;
428 int prevPkind = this.pkind;
429 Type prevPt = this.pt;
430 String prevErrKey = this.errKey;
431 try {
432 this.env = env;
433 this.pkind = pkind;
434 this.pt = pt;
435 this.errKey = errKey;
436 tree.accept(this);
437 if (tree == breakTree)
438 throw new BreakAttr(env);
439 return result;
440 } catch (CompletionFailure ex) {
441 tree.type = syms.errType;
442 return chk.completionError(tree.pos(), ex);
443 } finally {
444 this.env = prevEnv;
445 this.pkind = prevPkind;
446 this.pt = prevPt;
447 this.errKey = prevErrKey;
448 }
449 }
451 /** Derived visitor method: attribute an expression tree.
452 */
453 public Type attribExpr(JCTree tree, Env<AttrContext> env, Type pt) {
454 return attribTree(tree, env, VAL, pt.tag != ERROR ? pt : Type.noType);
455 }
457 public Type attribExpr(JCTree tree, Env<AttrContext> env, Type pt, String key) {
458 return attribTree(tree, env, VAL, pt.tag != ERROR ? pt : Type.noType, key);
459 }
461 /** Derived visitor method: attribute an expression tree with
462 * no constraints on the computed type.
463 */
464 Type attribExpr(JCTree tree, Env<AttrContext> env) {
465 return attribTree(tree, env, VAL, Type.noType);
466 }
468 /** Derived visitor method: attribute a type tree.
469 */
470 Type attribType(JCTree tree, Env<AttrContext> env) {
471 Type result = attribType(tree, env, Type.noType);
472 return result;
473 }
475 /** Derived visitor method: attribute a type tree.
476 */
477 Type attribType(JCTree tree, Env<AttrContext> env, Type pt) {
478 Type result = attribTree(tree, env, TYP, pt);
479 return result;
480 }
482 /** Derived visitor method: attribute a statement or definition tree.
483 */
484 public Type attribStat(JCTree tree, Env<AttrContext> env) {
485 return attribTree(tree, env, NIL, Type.noType);
486 }
488 /** Attribute a list of expressions, returning a list of types.
489 */
490 List<Type> attribExprs(List<JCExpression> trees, Env<AttrContext> env, Type pt) {
491 ListBuffer<Type> ts = new ListBuffer<Type>();
492 for (List<JCExpression> l = trees; l.nonEmpty(); l = l.tail)
493 ts.append(attribExpr(l.head, env, pt));
494 return ts.toList();
495 }
497 /** Attribute a list of statements, returning nothing.
498 */
499 <T extends JCTree> void attribStats(List<T> trees, Env<AttrContext> env) {
500 for (List<T> l = trees; l.nonEmpty(); l = l.tail)
501 attribStat(l.head, env);
502 }
504 /** Attribute the arguments in a method call, returning a list of types.
505 */
506 List<Type> attribArgs(List<JCExpression> trees, Env<AttrContext> env) {
507 ListBuffer<Type> argtypes = new ListBuffer<Type>();
508 for (List<JCExpression> l = trees; l.nonEmpty(); l = l.tail)
509 argtypes.append(chk.checkNonVoid(
510 l.head.pos(), types.upperBound(attribTree(l.head, env, VAL, Infer.anyPoly))));
511 return argtypes.toList();
512 }
514 /** Attribute a type argument list, returning a list of types.
515 * Caller is responsible for calling checkRefTypes.
516 */
517 List<Type> attribAnyTypes(List<JCExpression> trees, Env<AttrContext> env) {
518 ListBuffer<Type> argtypes = new ListBuffer<Type>();
519 for (List<JCExpression> l = trees; l.nonEmpty(); l = l.tail)
520 argtypes.append(attribType(l.head, env));
521 return argtypes.toList();
522 }
524 /** Attribute a type argument list, returning a list of types.
525 * Check that all the types are references.
526 */
527 List<Type> attribTypes(List<JCExpression> trees, Env<AttrContext> env) {
528 List<Type> types = attribAnyTypes(trees, env);
529 return chk.checkRefTypes(trees, types);
530 }
532 /**
533 * Attribute type variables (of generic classes or methods).
534 * Compound types are attributed later in attribBounds.
535 * @param typarams the type variables to enter
536 * @param env the current environment
537 */
538 void attribTypeVariables(List<JCTypeParameter> typarams, Env<AttrContext> env) {
539 for (JCTypeParameter tvar : typarams) {
540 TypeVar a = (TypeVar)tvar.type;
541 a.tsym.flags_field |= UNATTRIBUTED;
542 a.bound = Type.noType;
543 if (!tvar.bounds.isEmpty()) {
544 List<Type> bounds = List.of(attribType(tvar.bounds.head, env));
545 for (JCExpression bound : tvar.bounds.tail)
546 bounds = bounds.prepend(attribType(bound, env));
547 types.setBounds(a, bounds.reverse());
548 } else {
549 // if no bounds are given, assume a single bound of
550 // java.lang.Object.
551 types.setBounds(a, List.of(syms.objectType));
552 }
553 a.tsym.flags_field &= ~UNATTRIBUTED;
554 }
555 for (JCTypeParameter tvar : typarams)
556 chk.checkNonCyclic(tvar.pos(), (TypeVar)tvar.type);
557 attribStats(typarams, env);
558 }
560 void attribBounds(List<JCTypeParameter> typarams) {
561 for (JCTypeParameter typaram : typarams) {
562 Type bound = typaram.type.getUpperBound();
563 if (bound != null && bound.tsym instanceof ClassSymbol) {
564 ClassSymbol c = (ClassSymbol)bound.tsym;
565 if ((c.flags_field & COMPOUND) != 0) {
566 Assert.check((c.flags_field & UNATTRIBUTED) != 0, c);
567 attribClass(typaram.pos(), c);
568 }
569 }
570 }
571 }
573 /**
574 * Attribute the type references in a list of annotations.
575 */
576 void attribAnnotationTypes(List<JCAnnotation> annotations,
577 Env<AttrContext> env) {
578 for (List<JCAnnotation> al = annotations; al.nonEmpty(); al = al.tail) {
579 JCAnnotation a = al.head;
580 attribType(a.annotationType, env);
581 }
582 }
584 /**
585 * Attribute a "lazy constant value".
586 * @param env The env for the const value
587 * @param initializer The initializer for the const value
588 * @param type The expected type, or null
589 * @see VarSymbol#setlazyConstValue
590 */
591 public Object attribLazyConstantValue(Env<AttrContext> env,
592 JCTree.JCExpression initializer,
593 Type type) {
595 // in case no lint value has been set up for this env, scan up
596 // env stack looking for smallest enclosing env for which it is set.
597 Env<AttrContext> lintEnv = env;
598 while (lintEnv.info.lint == null)
599 lintEnv = lintEnv.next;
601 // Having found the enclosing lint value, we can initialize the lint value for this class
602 env.info.lint = lintEnv.info.lint.augment(env.info.enclVar.attributes_field, env.info.enclVar.flags());
604 Lint prevLint = chk.setLint(env.info.lint);
605 JavaFileObject prevSource = log.useSource(env.toplevel.sourcefile);
607 try {
608 Type itype = attribExpr(initializer, env, type);
609 if (itype.constValue() != null)
610 return coerce(itype, type).constValue();
611 else
612 return null;
613 } finally {
614 env.info.lint = prevLint;
615 log.useSource(prevSource);
616 }
617 }
619 /** Attribute type reference in an `extends' or `implements' clause.
620 * Supertypes of anonymous inner classes are usually already attributed.
621 *
622 * @param tree The tree making up the type reference.
623 * @param env The environment current at the reference.
624 * @param classExpected true if only a class is expected here.
625 * @param interfaceExpected true if only an interface is expected here.
626 */
627 Type attribBase(JCTree tree,
628 Env<AttrContext> env,
629 boolean classExpected,
630 boolean interfaceExpected,
631 boolean checkExtensible) {
632 Type t = tree.type != null ?
633 tree.type :
634 attribType(tree, env);
635 return checkBase(t, tree, env, classExpected, interfaceExpected, checkExtensible);
636 }
637 Type checkBase(Type t,
638 JCTree tree,
639 Env<AttrContext> env,
640 boolean classExpected,
641 boolean interfaceExpected,
642 boolean checkExtensible) {
643 if (t.isErroneous())
644 return t;
645 if (t.tag == TYPEVAR && !classExpected && !interfaceExpected) {
646 // check that type variable is already visible
647 if (t.getUpperBound() == null) {
648 log.error(tree.pos(), "illegal.forward.ref");
649 return types.createErrorType(t);
650 }
651 } else {
652 t = chk.checkClassType(tree.pos(), t, checkExtensible|!allowGenerics);
653 }
654 if (interfaceExpected && (t.tsym.flags() & INTERFACE) == 0) {
655 log.error(tree.pos(), "intf.expected.here");
656 // return errType is necessary since otherwise there might
657 // be undetected cycles which cause attribution to loop
658 return types.createErrorType(t);
659 } else if (checkExtensible &&
660 classExpected &&
661 (t.tsym.flags() & INTERFACE) != 0) {
662 log.error(tree.pos(), "no.intf.expected.here");
663 return types.createErrorType(t);
664 }
665 if (checkExtensible &&
666 ((t.tsym.flags() & FINAL) != 0)) {
667 log.error(tree.pos(),
668 "cant.inherit.from.final", t.tsym);
669 }
670 chk.checkNonCyclic(tree.pos(), t);
671 return t;
672 }
674 public void visitClassDef(JCClassDecl tree) {
675 // Local classes have not been entered yet, so we need to do it now:
676 if ((env.info.scope.owner.kind & (VAR | MTH)) != 0)
677 enter.classEnter(tree, env);
679 ClassSymbol c = tree.sym;
680 if (c == null) {
681 // exit in case something drastic went wrong during enter.
682 result = null;
683 } else {
684 // make sure class has been completed:
685 c.complete();
687 // If this class appears as an anonymous class
688 // in a superclass constructor call where
689 // no explicit outer instance is given,
690 // disable implicit outer instance from being passed.
691 // (This would be an illegal access to "this before super").
692 if (env.info.isSelfCall &&
693 env.tree.getTag() == JCTree.NEWCLASS &&
694 ((JCNewClass) env.tree).encl == null)
695 {
696 c.flags_field |= NOOUTERTHIS;
697 }
698 attribClass(tree.pos(), c);
699 result = tree.type = c.type;
700 }
701 }
703 public void visitMethodDef(JCMethodDecl tree) {
704 MethodSymbol m = tree.sym;
706 Lint lint = env.info.lint.augment(m.attributes_field, m.flags());
707 Lint prevLint = chk.setLint(lint);
708 MethodSymbol prevMethod = chk.setMethod(m);
709 try {
710 chk.checkDeprecatedAnnotation(tree.pos(), m);
712 attribBounds(tree.typarams);
714 // If we override any other methods, check that we do so properly.
715 // JLS ???
716 chk.checkClashes(tree.pos(), env.enclClass.type, m);
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);
853 try {
854 chk.checkDeprecatedAnnotation(tree.pos(), v);
856 if (tree.init != null) {
857 if ((v.flags_field & FINAL) != 0 && tree.init.getTag() != JCTree.NEWCLASS) {
858 // In this case, `v' is final. Ensure that it's initializer is
859 // evaluated.
860 v.getConstValue(); // ensure initializer is evaluated
861 } else {
862 // Attribute initializer in a new environment
863 // with the declared variable as owner.
864 // Check that initializer conforms to variable's declared type.
865 Env<AttrContext> initEnv = memberEnter.initEnv(tree, env);
866 initEnv.info.lint = lint;
867 // In order to catch self-references, we set the variable's
868 // declaration position to maximal possible value, effectively
869 // marking the variable as undefined.
870 initEnv.info.enclVar = v;
871 attribExpr(tree.init, initEnv, v.type);
872 }
873 }
874 result = tree.type = v.type;
875 chk.validateAnnotations(tree.mods.annotations, v);
876 }
877 finally {
878 chk.setLint(prevLint);
879 }
880 }
882 public void visitSkip(JCSkip tree) {
883 result = null;
884 }
886 public void visitBlock(JCBlock tree) {
887 if (env.info.scope.owner.kind == TYP) {
888 // Block is a static or instance initializer;
889 // let the owner of the environment be a freshly
890 // created BLOCK-method.
891 Env<AttrContext> localEnv =
892 env.dup(tree, env.info.dup(env.info.scope.dupUnshared()));
893 localEnv.info.scope.owner =
894 new MethodSymbol(tree.flags | BLOCK, names.empty, null,
895 env.info.scope.owner);
896 if ((tree.flags & STATIC) != 0) localEnv.info.staticLevel++;
897 attribStats(tree.stats, localEnv);
898 } else {
899 // Create a new local environment with a local scope.
900 Env<AttrContext> localEnv =
901 env.dup(tree, env.info.dup(env.info.scope.dup()));
902 attribStats(tree.stats, localEnv);
903 localEnv.info.scope.leave();
904 }
905 result = null;
906 }
908 public void visitDoLoop(JCDoWhileLoop tree) {
909 attribStat(tree.body, env.dup(tree));
910 attribExpr(tree.cond, env, syms.booleanType);
911 result = null;
912 }
914 public void visitWhileLoop(JCWhileLoop tree) {
915 attribExpr(tree.cond, env, syms.booleanType);
916 attribStat(tree.body, env.dup(tree));
917 result = null;
918 }
920 public void visitForLoop(JCForLoop tree) {
921 Env<AttrContext> loopEnv =
922 env.dup(env.tree, env.info.dup(env.info.scope.dup()));
923 attribStats(tree.init, loopEnv);
924 if (tree.cond != null) attribExpr(tree.cond, loopEnv, syms.booleanType);
925 loopEnv.tree = tree; // before, we were not in loop!
926 attribStats(tree.step, loopEnv);
927 attribStat(tree.body, loopEnv);
928 loopEnv.info.scope.leave();
929 result = null;
930 }
932 public void visitForeachLoop(JCEnhancedForLoop tree) {
933 Env<AttrContext> loopEnv =
934 env.dup(env.tree, env.info.dup(env.info.scope.dup()));
935 attribStat(tree.var, loopEnv);
936 Type exprType = types.upperBound(attribExpr(tree.expr, loopEnv));
937 chk.checkNonVoid(tree.pos(), exprType);
938 Type elemtype = types.elemtype(exprType); // perhaps expr is an array?
939 if (elemtype == null) {
940 // or perhaps expr implements Iterable<T>?
941 Type base = types.asSuper(exprType, syms.iterableType.tsym);
942 if (base == null) {
943 log.error(tree.expr.pos(),
944 "foreach.not.applicable.to.type",
945 exprType,
946 diags.fragment("type.req.array.or.iterable"));
947 elemtype = types.createErrorType(exprType);
948 } else {
949 List<Type> iterableParams = base.allparams();
950 elemtype = iterableParams.isEmpty()
951 ? syms.objectType
952 : types.upperBound(iterableParams.head);
953 }
954 }
955 chk.checkType(tree.expr.pos(), elemtype, tree.var.sym.type);
956 loopEnv.tree = tree; // before, we were not in loop!
957 attribStat(tree.body, loopEnv);
958 loopEnv.info.scope.leave();
959 result = null;
960 }
962 public void visitLabelled(JCLabeledStatement tree) {
963 // Check that label is not used in an enclosing statement
964 Env<AttrContext> env1 = env;
965 while (env1 != null && env1.tree.getTag() != JCTree.CLASSDEF) {
966 if (env1.tree.getTag() == JCTree.LABELLED &&
967 ((JCLabeledStatement) env1.tree).label == tree.label) {
968 log.error(tree.pos(), "label.already.in.use",
969 tree.label);
970 break;
971 }
972 env1 = env1.next;
973 }
975 attribStat(tree.body, env.dup(tree));
976 result = null;
977 }
979 public void visitSwitch(JCSwitch tree) {
980 Type seltype = attribExpr(tree.selector, env);
982 Env<AttrContext> switchEnv =
983 env.dup(tree, env.info.dup(env.info.scope.dup()));
985 boolean enumSwitch =
986 allowEnums &&
987 (seltype.tsym.flags() & Flags.ENUM) != 0;
988 boolean stringSwitch = false;
989 if (types.isSameType(seltype, syms.stringType)) {
990 if (allowStringsInSwitch) {
991 stringSwitch = true;
992 } else {
993 log.error(tree.selector.pos(), "string.switch.not.supported.in.source", sourceName);
994 }
995 }
996 if (!enumSwitch && !stringSwitch)
997 seltype = chk.checkType(tree.selector.pos(), seltype, syms.intType);
999 // Attribute all cases and
1000 // check that there are no duplicate case labels or default clauses.
1001 Set<Object> labels = new HashSet<Object>(); // The set of case labels.
1002 boolean hasDefault = false; // Is there a default label?
1003 for (List<JCCase> l = tree.cases; l.nonEmpty(); l = l.tail) {
1004 JCCase c = l.head;
1005 Env<AttrContext> caseEnv =
1006 switchEnv.dup(c, env.info.dup(switchEnv.info.scope.dup()));
1007 if (c.pat != null) {
1008 if (enumSwitch) {
1009 Symbol sym = enumConstant(c.pat, seltype);
1010 if (sym == null) {
1011 log.error(c.pat.pos(), "enum.label.must.be.unqualified.enum");
1012 } else if (!labels.add(sym)) {
1013 log.error(c.pos(), "duplicate.case.label");
1014 }
1015 } else {
1016 Type pattype = attribExpr(c.pat, switchEnv, seltype);
1017 if (pattype.tag != ERROR) {
1018 if (pattype.constValue() == null) {
1019 log.error(c.pat.pos(),
1020 (stringSwitch ? "string.const.req" : "const.expr.req"));
1021 } else if (labels.contains(pattype.constValue())) {
1022 log.error(c.pos(), "duplicate.case.label");
1023 } else {
1024 labels.add(pattype.constValue());
1025 }
1026 }
1027 }
1028 } else if (hasDefault) {
1029 log.error(c.pos(), "duplicate.default.label");
1030 } else {
1031 hasDefault = true;
1032 }
1033 attribStats(c.stats, caseEnv);
1034 caseEnv.info.scope.leave();
1035 addVars(c.stats, switchEnv.info.scope);
1036 }
1038 switchEnv.info.scope.leave();
1039 result = null;
1040 }
1041 // where
1042 /** Add any variables defined in stats to the switch scope. */
1043 private static void addVars(List<JCStatement> stats, Scope switchScope) {
1044 for (;stats.nonEmpty(); stats = stats.tail) {
1045 JCTree stat = stats.head;
1046 if (stat.getTag() == JCTree.VARDEF)
1047 switchScope.enter(((JCVariableDecl) stat).sym);
1048 }
1049 }
1050 // where
1051 /** Return the selected enumeration constant symbol, or null. */
1052 private Symbol enumConstant(JCTree tree, Type enumType) {
1053 if (tree.getTag() != JCTree.IDENT) {
1054 log.error(tree.pos(), "enum.label.must.be.unqualified.enum");
1055 return syms.errSymbol;
1056 }
1057 JCIdent ident = (JCIdent)tree;
1058 Name name = ident.name;
1059 for (Scope.Entry e = enumType.tsym.members().lookup(name);
1060 e.scope != null; e = e.next()) {
1061 if (e.sym.kind == VAR) {
1062 Symbol s = ident.sym = e.sym;
1063 ((VarSymbol)s).getConstValue(); // ensure initializer is evaluated
1064 ident.type = s.type;
1065 return ((s.flags_field & Flags.ENUM) == 0)
1066 ? null : s;
1067 }
1068 }
1069 return null;
1070 }
1072 public void visitSynchronized(JCSynchronized tree) {
1073 chk.checkRefType(tree.pos(), attribExpr(tree.lock, env));
1074 attribStat(tree.body, env);
1075 result = null;
1076 }
1078 public void visitTry(JCTry tree) {
1079 // Create a new local environment with a local
1080 Env<AttrContext> localEnv = env.dup(tree, env.info.dup(env.info.scope.dup()));
1081 boolean isTryWithResource = tree.resources.nonEmpty();
1082 // Create a nested environment for attributing the try block if needed
1083 Env<AttrContext> tryEnv = isTryWithResource ?
1084 env.dup(tree, localEnv.info.dup(localEnv.info.scope.dup())) :
1085 localEnv;
1086 // Attribute resource declarations
1087 for (JCTree resource : tree.resources) {
1088 if (resource.getTag() == JCTree.VARDEF) {
1089 attribStat(resource, tryEnv);
1090 chk.checkType(resource, resource.type, syms.autoCloseableType, "try.not.applicable.to.type");
1091 VarSymbol var = (VarSymbol)TreeInfo.symbolFor(resource);
1092 var.setData(ElementKind.RESOURCE_VARIABLE);
1093 } else {
1094 attribExpr(resource, tryEnv, syms.autoCloseableType, "try.not.applicable.to.type");
1095 }
1096 }
1097 // Attribute body
1098 attribStat(tree.body, tryEnv);
1099 if (isTryWithResource)
1100 tryEnv.info.scope.leave();
1102 // Attribute catch clauses
1103 for (List<JCCatch> l = tree.catchers; l.nonEmpty(); l = l.tail) {
1104 JCCatch c = l.head;
1105 Env<AttrContext> catchEnv =
1106 localEnv.dup(c, localEnv.info.dup(localEnv.info.scope.dup()));
1107 Type ctype = attribStat(c.param, catchEnv);
1108 if (TreeInfo.isMultiCatch(c)) {
1109 //multi-catch parameter is implicitly marked as final
1110 c.param.sym.flags_field |= FINAL | DISJUNCTION;
1111 }
1112 if (c.param.sym.kind == Kinds.VAR) {
1113 c.param.sym.setData(ElementKind.EXCEPTION_PARAMETER);
1114 }
1115 chk.checkType(c.param.vartype.pos(),
1116 chk.checkClassType(c.param.vartype.pos(), ctype),
1117 syms.throwableType);
1118 attribStat(c.body, catchEnv);
1119 catchEnv.info.scope.leave();
1120 }
1122 // Attribute finalizer
1123 if (tree.finalizer != null) attribStat(tree.finalizer, localEnv);
1125 localEnv.info.scope.leave();
1126 result = null;
1127 }
1129 public void visitConditional(JCConditional tree) {
1130 attribExpr(tree.cond, env, syms.booleanType);
1131 attribExpr(tree.truepart, env);
1132 attribExpr(tree.falsepart, env);
1133 result = check(tree,
1134 capture(condType(tree.pos(), tree.cond.type,
1135 tree.truepart.type, tree.falsepart.type)),
1136 VAL, pkind, pt);
1137 }
1138 //where
1139 /** Compute the type of a conditional expression, after
1140 * checking that it exists. See Spec 15.25.
1141 *
1142 * @param pos The source position to be used for
1143 * error diagnostics.
1144 * @param condtype The type of the expression's condition.
1145 * @param thentype The type of the expression's then-part.
1146 * @param elsetype The type of the expression's else-part.
1147 */
1148 private Type condType(DiagnosticPosition pos,
1149 Type condtype,
1150 Type thentype,
1151 Type elsetype) {
1152 Type ctype = condType1(pos, condtype, thentype, elsetype);
1154 // If condition and both arms are numeric constants,
1155 // evaluate at compile-time.
1156 return ((condtype.constValue() != null) &&
1157 (thentype.constValue() != null) &&
1158 (elsetype.constValue() != null))
1159 ? cfolder.coerce(condtype.isTrue()?thentype:elsetype, ctype)
1160 : ctype;
1161 }
1162 /** Compute the type of a conditional expression, after
1163 * checking that it exists. Does not take into
1164 * account the special case where condition and both arms
1165 * are constants.
1166 *
1167 * @param pos The source position to be used for error
1168 * diagnostics.
1169 * @param condtype The type of the expression's condition.
1170 * @param thentype The type of the expression's then-part.
1171 * @param elsetype The type of the expression's else-part.
1172 */
1173 private Type condType1(DiagnosticPosition pos, Type condtype,
1174 Type thentype, Type elsetype) {
1175 // If same type, that is the result
1176 if (types.isSameType(thentype, elsetype))
1177 return thentype.baseType();
1179 Type thenUnboxed = (!allowBoxing || thentype.isPrimitive())
1180 ? thentype : types.unboxedType(thentype);
1181 Type elseUnboxed = (!allowBoxing || elsetype.isPrimitive())
1182 ? elsetype : types.unboxedType(elsetype);
1184 // Otherwise, if both arms can be converted to a numeric
1185 // type, return the least numeric type that fits both arms
1186 // (i.e. return larger of the two, or return int if one
1187 // arm is short, the other is char).
1188 if (thenUnboxed.isPrimitive() && elseUnboxed.isPrimitive()) {
1189 // If one arm has an integer subrange type (i.e., byte,
1190 // short, or char), and the other is an integer constant
1191 // that fits into the subrange, return the subrange type.
1192 if (thenUnboxed.tag < INT && elseUnboxed.tag == INT &&
1193 types.isAssignable(elseUnboxed, thenUnboxed))
1194 return thenUnboxed.baseType();
1195 if (elseUnboxed.tag < INT && thenUnboxed.tag == INT &&
1196 types.isAssignable(thenUnboxed, elseUnboxed))
1197 return elseUnboxed.baseType();
1199 for (int i = BYTE; i < VOID; i++) {
1200 Type candidate = syms.typeOfTag[i];
1201 if (types.isSubtype(thenUnboxed, candidate) &&
1202 types.isSubtype(elseUnboxed, candidate))
1203 return candidate;
1204 }
1205 }
1207 // Those were all the cases that could result in a primitive
1208 if (allowBoxing) {
1209 if (thentype.isPrimitive())
1210 thentype = types.boxedClass(thentype).type;
1211 if (elsetype.isPrimitive())
1212 elsetype = types.boxedClass(elsetype).type;
1213 }
1215 if (types.isSubtype(thentype, elsetype))
1216 return elsetype.baseType();
1217 if (types.isSubtype(elsetype, thentype))
1218 return thentype.baseType();
1220 if (!allowBoxing || thentype.tag == VOID || elsetype.tag == VOID) {
1221 log.error(pos, "neither.conditional.subtype",
1222 thentype, elsetype);
1223 return thentype.baseType();
1224 }
1226 // both are known to be reference types. The result is
1227 // lub(thentype,elsetype). This cannot fail, as it will
1228 // always be possible to infer "Object" if nothing better.
1229 return types.lub(thentype.baseType(), elsetype.baseType());
1230 }
1232 public void visitIf(JCIf tree) {
1233 attribExpr(tree.cond, env, syms.booleanType);
1234 attribStat(tree.thenpart, env);
1235 if (tree.elsepart != null)
1236 attribStat(tree.elsepart, env);
1237 chk.checkEmptyIf(tree);
1238 result = null;
1239 }
1241 public void visitExec(JCExpressionStatement tree) {
1242 //a fresh environment is required for 292 inference to work properly ---
1243 //see Infer.instantiatePolymorphicSignatureInstance()
1244 Env<AttrContext> localEnv = env.dup(tree);
1245 attribExpr(tree.expr, localEnv);
1246 result = null;
1247 }
1249 public void visitBreak(JCBreak tree) {
1250 tree.target = findJumpTarget(tree.pos(), tree.getTag(), tree.label, env);
1251 result = null;
1252 }
1254 public void visitContinue(JCContinue tree) {
1255 tree.target = findJumpTarget(tree.pos(), tree.getTag(), tree.label, env);
1256 result = null;
1257 }
1258 //where
1259 /** Return the target of a break or continue statement, if it exists,
1260 * report an error if not.
1261 * Note: The target of a labelled break or continue is the
1262 * (non-labelled) statement tree referred to by the label,
1263 * not the tree representing the labelled statement itself.
1264 *
1265 * @param pos The position to be used for error diagnostics
1266 * @param tag The tag of the jump statement. This is either
1267 * Tree.BREAK or Tree.CONTINUE.
1268 * @param label The label of the jump statement, or null if no
1269 * label is given.
1270 * @param env The environment current at the jump statement.
1271 */
1272 private JCTree findJumpTarget(DiagnosticPosition pos,
1273 int tag,
1274 Name label,
1275 Env<AttrContext> env) {
1276 // Search environments outwards from the point of jump.
1277 Env<AttrContext> env1 = env;
1278 LOOP:
1279 while (env1 != null) {
1280 switch (env1.tree.getTag()) {
1281 case JCTree.LABELLED:
1282 JCLabeledStatement labelled = (JCLabeledStatement)env1.tree;
1283 if (label == labelled.label) {
1284 // If jump is a continue, check that target is a loop.
1285 if (tag == JCTree.CONTINUE) {
1286 if (labelled.body.getTag() != JCTree.DOLOOP &&
1287 labelled.body.getTag() != JCTree.WHILELOOP &&
1288 labelled.body.getTag() != JCTree.FORLOOP &&
1289 labelled.body.getTag() != JCTree.FOREACHLOOP)
1290 log.error(pos, "not.loop.label", label);
1291 // Found labelled statement target, now go inwards
1292 // to next non-labelled tree.
1293 return TreeInfo.referencedStatement(labelled);
1294 } else {
1295 return labelled;
1296 }
1297 }
1298 break;
1299 case JCTree.DOLOOP:
1300 case JCTree.WHILELOOP:
1301 case JCTree.FORLOOP:
1302 case JCTree.FOREACHLOOP:
1303 if (label == null) return env1.tree;
1304 break;
1305 case JCTree.SWITCH:
1306 if (label == null && tag == JCTree.BREAK) return env1.tree;
1307 break;
1308 case JCTree.METHODDEF:
1309 case JCTree.CLASSDEF:
1310 break LOOP;
1311 default:
1312 }
1313 env1 = env1.next;
1314 }
1315 if (label != null)
1316 log.error(pos, "undef.label", label);
1317 else if (tag == JCTree.CONTINUE)
1318 log.error(pos, "cont.outside.loop");
1319 else
1320 log.error(pos, "break.outside.switch.loop");
1321 return null;
1322 }
1324 public void visitReturn(JCReturn tree) {
1325 // Check that there is an enclosing method which is
1326 // nested within than the enclosing class.
1327 if (env.enclMethod == null ||
1328 env.enclMethod.sym.owner != env.enclClass.sym) {
1329 log.error(tree.pos(), "ret.outside.meth");
1331 } else {
1332 // Attribute return expression, if it exists, and check that
1333 // it conforms to result type of enclosing method.
1334 Symbol m = env.enclMethod.sym;
1335 if (m.type.getReturnType().tag == VOID) {
1336 if (tree.expr != null)
1337 log.error(tree.expr.pos(),
1338 "cant.ret.val.from.meth.decl.void");
1339 } else if (tree.expr == null) {
1340 log.error(tree.pos(), "missing.ret.val");
1341 } else {
1342 attribExpr(tree.expr, env, m.type.getReturnType());
1343 }
1344 }
1345 result = null;
1346 }
1348 public void visitThrow(JCThrow tree) {
1349 attribExpr(tree.expr, env, syms.throwableType);
1350 result = null;
1351 }
1353 public void visitAssert(JCAssert tree) {
1354 attribExpr(tree.cond, env, syms.booleanType);
1355 if (tree.detail != null) {
1356 chk.checkNonVoid(tree.detail.pos(), attribExpr(tree.detail, env));
1357 }
1358 result = null;
1359 }
1361 /** Visitor method for method invocations.
1362 * NOTE: The method part of an application will have in its type field
1363 * the return type of the method, not the method's type itself!
1364 */
1365 public void visitApply(JCMethodInvocation tree) {
1366 // The local environment of a method application is
1367 // a new environment nested in the current one.
1368 Env<AttrContext> localEnv = env.dup(tree, env.info.dup());
1370 // The types of the actual method arguments.
1371 List<Type> argtypes;
1373 // The types of the actual method type arguments.
1374 List<Type> typeargtypes = null;
1376 Name methName = TreeInfo.name(tree.meth);
1378 boolean isConstructorCall =
1379 methName == names._this || methName == names._super;
1381 if (isConstructorCall) {
1382 // We are seeing a ...this(...) or ...super(...) call.
1383 // Check that this is the first statement in a constructor.
1384 if (checkFirstConstructorStat(tree, env)) {
1386 // Record the fact
1387 // that this is a constructor call (using isSelfCall).
1388 localEnv.info.isSelfCall = true;
1390 // Attribute arguments, yielding list of argument types.
1391 argtypes = attribArgs(tree.args, localEnv);
1392 typeargtypes = attribTypes(tree.typeargs, localEnv);
1394 // Variable `site' points to the class in which the called
1395 // constructor is defined.
1396 Type site = env.enclClass.sym.type;
1397 if (methName == names._super) {
1398 if (site == syms.objectType) {
1399 log.error(tree.meth.pos(), "no.superclass", site);
1400 site = types.createErrorType(syms.objectType);
1401 } else {
1402 site = types.supertype(site);
1403 }
1404 }
1406 if (site.tag == CLASS) {
1407 Type encl = site.getEnclosingType();
1408 while (encl != null && encl.tag == TYPEVAR)
1409 encl = encl.getUpperBound();
1410 if (encl.tag == CLASS) {
1411 // we are calling a nested class
1413 if (tree.meth.getTag() == JCTree.SELECT) {
1414 JCTree qualifier = ((JCFieldAccess) tree.meth).selected;
1416 // We are seeing a prefixed call, of the form
1417 // <expr>.super(...).
1418 // Check that the prefix expression conforms
1419 // to the outer instance type of the class.
1420 chk.checkRefType(qualifier.pos(),
1421 attribExpr(qualifier, localEnv,
1422 encl));
1423 } else if (methName == names._super) {
1424 // qualifier omitted; check for existence
1425 // of an appropriate implicit qualifier.
1426 rs.resolveImplicitThis(tree.meth.pos(),
1427 localEnv, site);
1428 }
1429 } else if (tree.meth.getTag() == JCTree.SELECT) {
1430 log.error(tree.meth.pos(), "illegal.qual.not.icls",
1431 site.tsym);
1432 }
1434 // if we're calling a java.lang.Enum constructor,
1435 // prefix the implicit String and int parameters
1436 if (site.tsym == syms.enumSym && allowEnums)
1437 argtypes = argtypes.prepend(syms.intType).prepend(syms.stringType);
1439 // Resolve the called constructor under the assumption
1440 // that we are referring to a superclass instance of the
1441 // current instance (JLS ???).
1442 boolean selectSuperPrev = localEnv.info.selectSuper;
1443 localEnv.info.selectSuper = true;
1444 localEnv.info.varArgs = false;
1445 Symbol sym = rs.resolveConstructor(
1446 tree.meth.pos(), localEnv, site, argtypes, typeargtypes);
1447 localEnv.info.selectSuper = selectSuperPrev;
1449 // Set method symbol to resolved constructor...
1450 TreeInfo.setSymbol(tree.meth, sym);
1452 // ...and check that it is legal in the current context.
1453 // (this will also set the tree's type)
1454 Type mpt = newMethTemplate(argtypes, typeargtypes);
1455 checkId(tree.meth, site, sym, localEnv, MTH,
1456 mpt, tree.varargsElement != null);
1457 }
1458 // Otherwise, `site' is an error type and we do nothing
1459 }
1460 result = tree.type = syms.voidType;
1461 } else {
1462 // Otherwise, we are seeing a regular method call.
1463 // Attribute the arguments, yielding list of argument types, ...
1464 argtypes = attribArgs(tree.args, localEnv);
1465 typeargtypes = attribAnyTypes(tree.typeargs, localEnv);
1467 // ... and attribute the method using as a prototype a methodtype
1468 // whose formal argument types is exactly the list of actual
1469 // arguments (this will also set the method symbol).
1470 Type mpt = newMethTemplate(argtypes, typeargtypes);
1471 localEnv.info.varArgs = false;
1472 Type mtype = attribExpr(tree.meth, localEnv, mpt);
1473 if (localEnv.info.varArgs)
1474 Assert.check(mtype.isErroneous() || tree.varargsElement != null);
1476 // Compute the result type.
1477 Type restype = mtype.getReturnType();
1478 if (restype.tag == WILDCARD)
1479 throw new AssertionError(mtype);
1481 // as a special case, array.clone() has a result that is
1482 // the same as static type of the array being cloned
1483 if (tree.meth.getTag() == JCTree.SELECT &&
1484 allowCovariantReturns &&
1485 methName == names.clone &&
1486 types.isArray(((JCFieldAccess) tree.meth).selected.type))
1487 restype = ((JCFieldAccess) tree.meth).selected.type;
1489 // as a special case, x.getClass() has type Class<? extends |X|>
1490 if (allowGenerics &&
1491 methName == names.getClass && tree.args.isEmpty()) {
1492 Type qualifier = (tree.meth.getTag() == JCTree.SELECT)
1493 ? ((JCFieldAccess) tree.meth).selected.type
1494 : env.enclClass.sym.type;
1495 restype = new
1496 ClassType(restype.getEnclosingType(),
1497 List.<Type>of(new WildcardType(types.erasure(qualifier),
1498 BoundKind.EXTENDS,
1499 syms.boundClass)),
1500 restype.tsym);
1501 }
1503 chk.checkRefTypes(tree.typeargs, typeargtypes);
1505 // Check that value of resulting type is admissible in the
1506 // current context. Also, capture the return type
1507 result = check(tree, capture(restype), VAL, pkind, pt);
1508 }
1509 chk.validate(tree.typeargs, localEnv);
1510 }
1511 //where
1512 /** Check that given application node appears as first statement
1513 * in a constructor call.
1514 * @param tree The application node
1515 * @param env The environment current at the application.
1516 */
1517 boolean checkFirstConstructorStat(JCMethodInvocation tree, Env<AttrContext> env) {
1518 JCMethodDecl enclMethod = env.enclMethod;
1519 if (enclMethod != null && enclMethod.name == names.init) {
1520 JCBlock body = enclMethod.body;
1521 if (body.stats.head.getTag() == JCTree.EXEC &&
1522 ((JCExpressionStatement) body.stats.head).expr == tree)
1523 return true;
1524 }
1525 log.error(tree.pos(),"call.must.be.first.stmt.in.ctor",
1526 TreeInfo.name(tree.meth));
1527 return false;
1528 }
1530 /** Obtain a method type with given argument types.
1531 */
1532 Type newMethTemplate(List<Type> argtypes, List<Type> typeargtypes) {
1533 MethodType mt = new MethodType(argtypes, null, null, syms.methodClass);
1534 return (typeargtypes == null) ? mt : (Type)new ForAll(typeargtypes, mt);
1535 }
1537 public void visitNewClass(JCNewClass tree) {
1538 Type owntype = types.createErrorType(tree.type);
1540 // The local environment of a class creation is
1541 // a new environment nested in the current one.
1542 Env<AttrContext> localEnv = env.dup(tree, env.info.dup());
1544 // The anonymous inner class definition of the new expression,
1545 // if one is defined by it.
1546 JCClassDecl cdef = tree.def;
1548 // If enclosing class is given, attribute it, and
1549 // complete class name to be fully qualified
1550 JCExpression clazz = tree.clazz; // Class field following new
1551 JCExpression clazzid = // Identifier in class field
1552 (clazz.getTag() == JCTree.TYPEAPPLY)
1553 ? ((JCTypeApply) clazz).clazz
1554 : clazz;
1556 JCExpression clazzid1 = clazzid; // The same in fully qualified form
1558 if (tree.encl != null) {
1559 // We are seeing a qualified new, of the form
1560 // <expr>.new C <...> (...) ...
1561 // In this case, we let clazz stand for the name of the
1562 // allocated class C prefixed with the type of the qualifier
1563 // expression, so that we can
1564 // resolve it with standard techniques later. I.e., if
1565 // <expr> has type T, then <expr>.new C <...> (...)
1566 // yields a clazz T.C.
1567 Type encltype = chk.checkRefType(tree.encl.pos(),
1568 attribExpr(tree.encl, env));
1569 clazzid1 = make.at(clazz.pos).Select(make.Type(encltype),
1570 ((JCIdent) clazzid).name);
1571 if (clazz.getTag() == JCTree.TYPEAPPLY)
1572 clazz = make.at(tree.pos).
1573 TypeApply(clazzid1,
1574 ((JCTypeApply) clazz).arguments);
1575 else
1576 clazz = clazzid1;
1577 }
1579 // Attribute clazz expression and store
1580 // symbol + type back into the attributed tree.
1581 Type clazztype = attribType(clazz, env);
1582 Pair<Scope,Scope> mapping = getSyntheticScopeMapping(clazztype, cdef != null);
1583 if (!TreeInfo.isDiamond(tree)) {
1584 clazztype = chk.checkClassType(
1585 tree.clazz.pos(), clazztype, true);
1586 }
1587 chk.validate(clazz, localEnv);
1588 if (tree.encl != null) {
1589 // We have to work in this case to store
1590 // symbol + type back into the attributed tree.
1591 tree.clazz.type = clazztype;
1592 TreeInfo.setSymbol(clazzid, TreeInfo.symbol(clazzid1));
1593 clazzid.type = ((JCIdent) clazzid).sym.type;
1594 if (!clazztype.isErroneous()) {
1595 if (cdef != null && clazztype.tsym.isInterface()) {
1596 log.error(tree.encl.pos(), "anon.class.impl.intf.no.qual.for.new");
1597 } else if (clazztype.tsym.isStatic()) {
1598 log.error(tree.encl.pos(), "qualified.new.of.static.class", clazztype.tsym);
1599 }
1600 }
1601 } else if (!clazztype.tsym.isInterface() &&
1602 clazztype.getEnclosingType().tag == CLASS) {
1603 // Check for the existence of an apropos outer instance
1604 rs.resolveImplicitThis(tree.pos(), env, clazztype);
1605 }
1607 // Attribute constructor arguments.
1608 List<Type> argtypes = attribArgs(tree.args, localEnv);
1609 List<Type> typeargtypes = attribTypes(tree.typeargs, localEnv);
1611 if (TreeInfo.isDiamond(tree)) {
1612 clazztype = attribDiamond(localEnv, tree, clazztype, mapping, argtypes, typeargtypes);
1613 clazz.type = clazztype;
1614 } else if (allowDiamondFinder &&
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 chk.checkDiamond((ClassType)inferred).isEmpty()) {
1640 String key = types.isSameType(clazztype, inferred) ?
1641 "diamond.redundant.args" :
1642 "diamond.redundant.args.1";
1643 log.warning(tree.clazz.pos(), key, clazztype, inferred);
1644 }
1645 }
1647 // If we have made no mistakes in the class type...
1648 if (clazztype.tag == CLASS) {
1649 // Enums may not be instantiated except implicitly
1650 if (allowEnums &&
1651 (clazztype.tsym.flags_field&Flags.ENUM) != 0 &&
1652 (env.tree.getTag() != JCTree.VARDEF ||
1653 (((JCVariableDecl) env.tree).mods.flags&Flags.ENUM) == 0 ||
1654 ((JCVariableDecl) env.tree).init != tree))
1655 log.error(tree.pos(), "enum.cant.be.instantiated");
1656 // Check that class is not abstract
1657 if (cdef == null &&
1658 (clazztype.tsym.flags() & (ABSTRACT | INTERFACE)) != 0) {
1659 log.error(tree.pos(), "abstract.cant.be.instantiated",
1660 clazztype.tsym);
1661 } else if (cdef != null && clazztype.tsym.isInterface()) {
1662 // Check that no constructor arguments are given to
1663 // anonymous classes implementing an interface
1664 if (!argtypes.isEmpty())
1665 log.error(tree.args.head.pos(), "anon.class.impl.intf.no.args");
1667 if (!typeargtypes.isEmpty())
1668 log.error(tree.typeargs.head.pos(), "anon.class.impl.intf.no.typeargs");
1670 // Error recovery: pretend no arguments were supplied.
1671 argtypes = List.nil();
1672 typeargtypes = List.nil();
1673 }
1675 // Resolve the called constructor under the assumption
1676 // that we are referring to a superclass instance of the
1677 // current instance (JLS ???).
1678 else {
1679 localEnv.info.selectSuper = cdef != null;
1680 localEnv.info.varArgs = false;
1681 tree.constructor = rs.resolveConstructor(
1682 tree.pos(), localEnv, clazztype, argtypes, typeargtypes);
1683 tree.constructorType = tree.constructor.type.isErroneous() ?
1684 syms.errType :
1685 checkMethod(clazztype,
1686 tree.constructor,
1687 localEnv,
1688 tree.args,
1689 argtypes,
1690 typeargtypes,
1691 localEnv.info.varArgs);
1692 if (localEnv.info.varArgs)
1693 Assert.check(tree.constructorType.isErroneous() || tree.varargsElement != null);
1694 }
1696 if (cdef != null) {
1697 // We are seeing an anonymous class instance creation.
1698 // In this case, the class instance creation
1699 // expression
1700 //
1701 // E.new <typeargs1>C<typargs2>(args) { ... }
1702 //
1703 // is represented internally as
1704 //
1705 // E . new <typeargs1>C<typargs2>(args) ( class <empty-name> { ... } ) .
1706 //
1707 // This expression is then *transformed* as follows:
1708 //
1709 // (1) add a STATIC flag to the class definition
1710 // if the current environment is static
1711 // (2) add an extends or implements clause
1712 // (3) add a constructor.
1713 //
1714 // For instance, if C is a class, and ET is the type of E,
1715 // the expression
1716 //
1717 // E.new <typeargs1>C<typargs2>(args) { ... }
1718 //
1719 // is translated to (where X is a fresh name and typarams is the
1720 // parameter list of the super constructor):
1721 //
1722 // new <typeargs1>X(<*nullchk*>E, args) where
1723 // X extends C<typargs2> {
1724 // <typarams> X(ET e, args) {
1725 // e.<typeargs1>super(args)
1726 // }
1727 // ...
1728 // }
1729 if (Resolve.isStatic(env)) cdef.mods.flags |= STATIC;
1731 if (clazztype.tsym.isInterface()) {
1732 cdef.implementing = List.of(clazz);
1733 } else {
1734 cdef.extending = clazz;
1735 }
1737 attribStat(cdef, localEnv);
1739 // If an outer instance is given,
1740 // prefix it to the constructor arguments
1741 // and delete it from the new expression
1742 if (tree.encl != null && !clazztype.tsym.isInterface()) {
1743 tree.args = tree.args.prepend(makeNullCheck(tree.encl));
1744 argtypes = argtypes.prepend(tree.encl.type);
1745 tree.encl = null;
1746 }
1748 // Reassign clazztype and recompute constructor.
1749 clazztype = cdef.sym.type;
1750 Symbol sym = rs.resolveConstructor(
1751 tree.pos(), localEnv, clazztype, argtypes,
1752 typeargtypes, true, tree.varargsElement != null);
1753 Assert.check(sym.kind < AMBIGUOUS || tree.constructor.type.isErroneous());
1754 tree.constructor = sym;
1755 if (tree.constructor.kind > ERRONEOUS) {
1756 tree.constructorType = syms.errType;
1757 }
1758 else {
1759 tree.constructorType = checkMethod(clazztype,
1760 tree.constructor,
1761 localEnv,
1762 tree.args,
1763 argtypes,
1764 typeargtypes,
1765 localEnv.info.varArgs);
1766 }
1767 }
1769 if (tree.constructor != null && tree.constructor.kind == MTH)
1770 owntype = clazztype;
1771 }
1772 result = check(tree, owntype, VAL, pkind, pt);
1773 chk.validate(tree.typeargs, localEnv);
1774 }
1776 Type attribDiamond(Env<AttrContext> env,
1777 JCNewClass tree,
1778 Type clazztype,
1779 Pair<Scope, Scope> mapping,
1780 List<Type> argtypes,
1781 List<Type> typeargtypes) {
1782 if (clazztype.isErroneous() || mapping == erroneousMapping) {
1783 //if the type of the instance creation expression is erroneous,
1784 //or something prevented us to form a valid mapping, return the
1785 //(possibly erroneous) type unchanged
1786 return clazztype;
1787 }
1788 else if (clazztype.isInterface()) {
1789 //if the type of the instance creation expression is an interface
1790 //skip the method resolution step (JLS 15.12.2.7). The type to be
1791 //inferred is of the kind <X1,X2, ... Xn>C<X1,X2, ... Xn>
1792 clazztype = new ForAll(clazztype.tsym.type.allparams(), clazztype.tsym.type) {
1793 @Override
1794 public List<Type> getConstraints(TypeVar tv, ConstraintKind ck) {
1795 switch (ck) {
1796 case EXTENDS: return types.getBounds(tv);
1797 default: return List.nil();
1798 }
1799 }
1800 @Override
1801 public Type inst(List<Type> inferred, Types types) throws Infer.NoInstanceException {
1802 // check that inferred bounds conform to their bounds
1803 infer.checkWithinBounds(tvars,
1804 types.subst(tvars, tvars, inferred), Warner.noWarnings);
1805 return super.inst(inferred, types);
1806 }
1807 };
1808 } else {
1809 //if the type of the instance creation expression is a class type
1810 //apply method resolution inference (JLS 15.12.2.7). The return type
1811 //of the resolved constructor will be a partially instantiated type
1812 ((ClassSymbol) clazztype.tsym).members_field = mapping.snd;
1813 Symbol constructor;
1814 try {
1815 constructor = rs.resolveDiamond(tree.pos(),
1816 env,
1817 clazztype.tsym.type,
1818 argtypes,
1819 typeargtypes);
1820 } finally {
1821 ((ClassSymbol) clazztype.tsym).members_field = mapping.fst;
1822 }
1823 if (constructor.kind == MTH) {
1824 ClassType ct = new ClassType(clazztype.getEnclosingType(),
1825 clazztype.tsym.type.getTypeArguments(),
1826 clazztype.tsym);
1827 clazztype = checkMethod(ct,
1828 constructor,
1829 env,
1830 tree.args,
1831 argtypes,
1832 typeargtypes,
1833 env.info.varArgs).getReturnType();
1834 } else {
1835 clazztype = syms.errType;
1836 }
1837 }
1838 if (clazztype.tag == FORALL && !pt.isErroneous()) {
1839 //if the resolved constructor's return type has some uninferred
1840 //type-variables, infer them using the expected type and declared
1841 //bounds (JLS 15.12.2.8).
1842 try {
1843 clazztype = infer.instantiateExpr((ForAll) clazztype,
1844 pt.tag == NONE ? syms.objectType : pt,
1845 Warner.noWarnings);
1846 } catch (Infer.InferenceException ex) {
1847 //an error occurred while inferring uninstantiated type-variables
1848 log.error(tree.clazz.pos(),
1849 "cant.apply.diamond.1",
1850 diags.fragment("diamond", clazztype.tsym),
1851 ex.diagnostic);
1852 }
1853 }
1854 clazztype = chk.checkClassType(tree.clazz.pos(),
1855 clazztype,
1856 true);
1857 if (clazztype.tag == CLASS) {
1858 List<Type> invalidDiamondArgs = chk.checkDiamond((ClassType)clazztype);
1859 if (!clazztype.isErroneous() && invalidDiamondArgs.nonEmpty()) {
1860 //one or more types inferred in the previous steps is either a
1861 //captured type or an intersection type --- we need to report an error.
1862 String subkey = invalidDiamondArgs.size() > 1 ?
1863 "diamond.invalid.args" :
1864 "diamond.invalid.arg";
1865 //The error message is of the kind:
1866 //
1867 //cannot infer type arguments for {clazztype}<>;
1868 //reason: {subkey}
1869 //
1870 //where subkey is a fragment of the kind:
1871 //
1872 //type argument(s) {invalidDiamondArgs} inferred for {clazztype}<> is not allowed in this context
1873 log.error(tree.clazz.pos(),
1874 "cant.apply.diamond.1",
1875 diags.fragment("diamond", clazztype.tsym),
1876 diags.fragment(subkey,
1877 invalidDiamondArgs,
1878 diags.fragment("diamond", clazztype.tsym)));
1879 }
1880 }
1881 return clazztype;
1882 }
1884 /** Creates a synthetic scope containing fake generic constructors.
1885 * Assuming that the original scope contains a constructor of the kind:
1886 * Foo(X x, Y y), where X,Y are class type-variables declared in Foo,
1887 * the synthetic scope is added a generic constructor of the kind:
1888 * <X,Y>Foo<X,Y>(X x, Y y). This is crucial in order to enable diamond
1889 * inference. The inferred return type of the synthetic constructor IS
1890 * the inferred type for the diamond operator.
1891 */
1892 private Pair<Scope, Scope> getSyntheticScopeMapping(Type ctype, boolean overrideProtectedAccess) {
1893 if (ctype.tag != CLASS) {
1894 return erroneousMapping;
1895 }
1896 Pair<Scope, Scope> mapping =
1897 new Pair<Scope, Scope>(ctype.tsym.members(), new Scope(ctype.tsym));
1898 List<Type> typevars = ctype.tsym.type.getTypeArguments();
1899 for (Scope.Entry e = mapping.fst.lookup(names.init);
1900 e.scope != null;
1901 e = e.next()) {
1902 MethodSymbol newConstr = (MethodSymbol) e.sym.clone(ctype.tsym);
1903 if (overrideProtectedAccess && (newConstr.flags() & PROTECTED) != 0) {
1904 //make protected constructor public (this is required for
1905 //anonymous inner class creation expressions using diamond)
1906 newConstr.flags_field |= PUBLIC;
1907 newConstr.flags_field &= ~PROTECTED;
1908 }
1909 newConstr.name = names.init;
1910 List<Type> oldTypeargs = List.nil();
1911 if (newConstr.type.tag == FORALL) {
1912 oldTypeargs = ((ForAll) newConstr.type).tvars;
1913 }
1914 newConstr.type = new MethodType(newConstr.type.getParameterTypes(),
1915 new ClassType(ctype.getEnclosingType(), ctype.tsym.type.getTypeArguments(), ctype.tsym),
1916 newConstr.type.getThrownTypes(),
1917 syms.methodClass);
1918 newConstr.type = new ForAll(typevars.prependList(oldTypeargs), newConstr.type);
1919 mapping.snd.enter(newConstr);
1920 }
1921 return mapping;
1922 }
1924 private final Pair<Scope,Scope> erroneousMapping = new Pair<Scope,Scope>(null, null);
1926 /** Make an attributed null check tree.
1927 */
1928 public JCExpression makeNullCheck(JCExpression arg) {
1929 // optimization: X.this is never null; skip null check
1930 Name name = TreeInfo.name(arg);
1931 if (name == names._this || name == names._super) return arg;
1933 int optag = JCTree.NULLCHK;
1934 JCUnary tree = make.at(arg.pos).Unary(optag, arg);
1935 tree.operator = syms.nullcheck;
1936 tree.type = arg.type;
1937 return tree;
1938 }
1940 public void visitNewArray(JCNewArray tree) {
1941 Type owntype = types.createErrorType(tree.type);
1942 Type elemtype;
1943 if (tree.elemtype != null) {
1944 elemtype = attribType(tree.elemtype, env);
1945 chk.validate(tree.elemtype, env);
1946 owntype = elemtype;
1947 for (List<JCExpression> l = tree.dims; l.nonEmpty(); l = l.tail) {
1948 attribExpr(l.head, env, syms.intType);
1949 owntype = new ArrayType(owntype, syms.arrayClass);
1950 }
1951 } else {
1952 // we are seeing an untyped aggregate { ... }
1953 // this is allowed only if the prototype is an array
1954 if (pt.tag == ARRAY) {
1955 elemtype = types.elemtype(pt);
1956 } else {
1957 if (pt.tag != ERROR) {
1958 log.error(tree.pos(), "illegal.initializer.for.type",
1959 pt);
1960 }
1961 elemtype = types.createErrorType(pt);
1962 }
1963 }
1964 if (tree.elems != null) {
1965 attribExprs(tree.elems, env, elemtype);
1966 owntype = new ArrayType(elemtype, syms.arrayClass);
1967 }
1968 if (!types.isReifiable(elemtype))
1969 log.error(tree.pos(), "generic.array.creation");
1970 result = check(tree, owntype, VAL, pkind, pt);
1971 }
1973 public void visitParens(JCParens tree) {
1974 Type owntype = attribTree(tree.expr, env, pkind, pt);
1975 result = check(tree, owntype, pkind, pkind, pt);
1976 Symbol sym = TreeInfo.symbol(tree);
1977 if (sym != null && (sym.kind&(TYP|PCK)) != 0)
1978 log.error(tree.pos(), "illegal.start.of.type");
1979 }
1981 public void visitAssign(JCAssign tree) {
1982 Type owntype = attribTree(tree.lhs, env.dup(tree), VAR, Type.noType);
1983 Type capturedType = capture(owntype);
1984 attribExpr(tree.rhs, env, owntype);
1985 result = check(tree, capturedType, VAL, pkind, pt);
1986 }
1988 public void visitAssignop(JCAssignOp tree) {
1989 // Attribute arguments.
1990 Type owntype = attribTree(tree.lhs, env, VAR, Type.noType);
1991 Type operand = attribExpr(tree.rhs, env);
1992 // Find operator.
1993 Symbol operator = tree.operator = rs.resolveBinaryOperator(
1994 tree.pos(), tree.getTag() - JCTree.ASGOffset, env,
1995 owntype, operand);
1997 if (operator.kind == MTH) {
1998 chk.checkOperator(tree.pos(),
1999 (OperatorSymbol)operator,
2000 tree.getTag() - JCTree.ASGOffset,
2001 owntype,
2002 operand);
2003 chk.checkDivZero(tree.rhs.pos(), operator, operand);
2004 chk.checkCastable(tree.rhs.pos(),
2005 operator.type.getReturnType(),
2006 owntype);
2007 }
2008 result = check(tree, owntype, VAL, pkind, pt);
2009 }
2011 public void visitUnary(JCUnary tree) {
2012 // Attribute arguments.
2013 Type argtype = (JCTree.PREINC <= tree.getTag() && tree.getTag() <= JCTree.POSTDEC)
2014 ? attribTree(tree.arg, env, VAR, Type.noType)
2015 : chk.checkNonVoid(tree.arg.pos(), attribExpr(tree.arg, env));
2017 // Find operator.
2018 Symbol operator = tree.operator =
2019 rs.resolveUnaryOperator(tree.pos(), tree.getTag(), env, argtype);
2021 Type owntype = types.createErrorType(tree.type);
2022 if (operator.kind == MTH) {
2023 owntype = (JCTree.PREINC <= tree.getTag() && tree.getTag() <= JCTree.POSTDEC)
2024 ? tree.arg.type
2025 : operator.type.getReturnType();
2026 int opc = ((OperatorSymbol)operator).opcode;
2028 // If the argument is constant, fold it.
2029 if (argtype.constValue() != null) {
2030 Type ctype = cfolder.fold1(opc, argtype);
2031 if (ctype != null) {
2032 owntype = cfolder.coerce(ctype, owntype);
2034 // Remove constant types from arguments to
2035 // conserve space. The parser will fold concatenations
2036 // of string literals; the code here also
2037 // gets rid of intermediate results when some of the
2038 // operands are constant identifiers.
2039 if (tree.arg.type.tsym == syms.stringType.tsym) {
2040 tree.arg.type = syms.stringType;
2041 }
2042 }
2043 }
2044 }
2045 result = check(tree, owntype, VAL, pkind, pt);
2046 }
2048 public void visitBinary(JCBinary tree) {
2049 // Attribute arguments.
2050 Type left = chk.checkNonVoid(tree.lhs.pos(), attribExpr(tree.lhs, env));
2051 Type right = chk.checkNonVoid(tree.lhs.pos(), attribExpr(tree.rhs, env));
2053 // Find operator.
2054 Symbol operator = tree.operator =
2055 rs.resolveBinaryOperator(tree.pos(), tree.getTag(), env, left, right);
2057 Type owntype = types.createErrorType(tree.type);
2058 if (operator.kind == MTH) {
2059 owntype = operator.type.getReturnType();
2060 int opc = chk.checkOperator(tree.lhs.pos(),
2061 (OperatorSymbol)operator,
2062 tree.getTag(),
2063 left,
2064 right);
2066 // If both arguments are constants, fold them.
2067 if (left.constValue() != null && right.constValue() != null) {
2068 Type ctype = cfolder.fold2(opc, left, right);
2069 if (ctype != null) {
2070 owntype = cfolder.coerce(ctype, owntype);
2072 // Remove constant types from arguments to
2073 // conserve space. The parser will fold concatenations
2074 // of string literals; the code here also
2075 // gets rid of intermediate results when some of the
2076 // operands are constant identifiers.
2077 if (tree.lhs.type.tsym == syms.stringType.tsym) {
2078 tree.lhs.type = syms.stringType;
2079 }
2080 if (tree.rhs.type.tsym == syms.stringType.tsym) {
2081 tree.rhs.type = syms.stringType;
2082 }
2083 }
2084 }
2086 // Check that argument types of a reference ==, != are
2087 // castable to each other, (JLS???).
2088 if ((opc == ByteCodes.if_acmpeq || opc == ByteCodes.if_acmpne)) {
2089 if (!types.isCastable(left, right, new Warner(tree.pos()))) {
2090 log.error(tree.pos(), "incomparable.types", left, right);
2091 }
2092 }
2094 chk.checkDivZero(tree.rhs.pos(), operator, right);
2095 }
2096 result = check(tree, owntype, VAL, pkind, pt);
2097 }
2099 public void visitTypeCast(JCTypeCast tree) {
2100 Type clazztype = attribType(tree.clazz, env);
2101 chk.validate(tree.clazz, env, false);
2102 //a fresh environment is required for 292 inference to work properly ---
2103 //see Infer.instantiatePolymorphicSignatureInstance()
2104 Env<AttrContext> localEnv = env.dup(tree);
2105 Type exprtype = attribExpr(tree.expr, localEnv, Infer.anyPoly);
2106 Type owntype = chk.checkCastable(tree.expr.pos(), exprtype, clazztype);
2107 if (exprtype.constValue() != null)
2108 owntype = cfolder.coerce(exprtype, owntype);
2109 result = check(tree, capture(owntype), VAL, pkind, pt);
2110 }
2112 public void visitTypeTest(JCInstanceOf tree) {
2113 Type exprtype = chk.checkNullOrRefType(
2114 tree.expr.pos(), attribExpr(tree.expr, env));
2115 Type clazztype = chk.checkReifiableReferenceType(
2116 tree.clazz.pos(), attribType(tree.clazz, env));
2117 chk.validate(tree.clazz, env, false);
2118 chk.checkCastable(tree.expr.pos(), exprtype, clazztype);
2119 result = check(tree, syms.booleanType, VAL, pkind, pt);
2120 }
2122 public void visitIndexed(JCArrayAccess tree) {
2123 Type owntype = types.createErrorType(tree.type);
2124 Type atype = attribExpr(tree.indexed, env);
2125 attribExpr(tree.index, env, syms.intType);
2126 if (types.isArray(atype))
2127 owntype = types.elemtype(atype);
2128 else if (atype.tag != ERROR)
2129 log.error(tree.pos(), "array.req.but.found", atype);
2130 if ((pkind & VAR) == 0) owntype = capture(owntype);
2131 result = check(tree, owntype, VAR, pkind, pt);
2132 }
2134 public void visitIdent(JCIdent tree) {
2135 Symbol sym;
2136 boolean varArgs = false;
2138 // Find symbol
2139 if (pt.tag == METHOD || pt.tag == FORALL) {
2140 // If we are looking for a method, the prototype `pt' will be a
2141 // method type with the type of the call's arguments as parameters.
2142 env.info.varArgs = false;
2143 sym = rs.resolveMethod(tree.pos(), env, tree.name, pt.getParameterTypes(), pt.getTypeArguments());
2144 varArgs = env.info.varArgs;
2145 } else if (tree.sym != null && tree.sym.kind != VAR) {
2146 sym = tree.sym;
2147 } else {
2148 sym = rs.resolveIdent(tree.pos(), env, tree.name, pkind);
2149 }
2150 tree.sym = sym;
2152 // (1) Also find the environment current for the class where
2153 // sym is defined (`symEnv').
2154 // Only for pre-tiger versions (1.4 and earlier):
2155 // (2) Also determine whether we access symbol out of an anonymous
2156 // class in a this or super call. This is illegal for instance
2157 // members since such classes don't carry a this$n link.
2158 // (`noOuterThisPath').
2159 Env<AttrContext> symEnv = env;
2160 boolean noOuterThisPath = false;
2161 if (env.enclClass.sym.owner.kind != PCK && // we are in an inner class
2162 (sym.kind & (VAR | MTH | TYP)) != 0 &&
2163 sym.owner.kind == TYP &&
2164 tree.name != names._this && tree.name != names._super) {
2166 // Find environment in which identifier is defined.
2167 while (symEnv.outer != null &&
2168 !sym.isMemberOf(symEnv.enclClass.sym, types)) {
2169 if ((symEnv.enclClass.sym.flags() & NOOUTERTHIS) != 0)
2170 noOuterThisPath = !allowAnonOuterThis;
2171 symEnv = symEnv.outer;
2172 }
2173 }
2175 // If symbol is a variable, ...
2176 if (sym.kind == VAR) {
2177 VarSymbol v = (VarSymbol)sym;
2179 // ..., evaluate its initializer, if it has one, and check for
2180 // illegal forward reference.
2181 checkInit(tree, env, v, false);
2183 // If symbol is a local variable accessed from an embedded
2184 // inner class check that it is final.
2185 if (v.owner.kind == MTH &&
2186 v.owner != env.info.scope.owner &&
2187 (v.flags_field & FINAL) == 0) {
2188 log.error(tree.pos(),
2189 "local.var.accessed.from.icls.needs.final",
2190 v);
2191 }
2193 // If we are expecting a variable (as opposed to a value), check
2194 // that the variable is assignable in the current environment.
2195 if (pkind == VAR)
2196 checkAssignable(tree.pos(), v, null, env);
2197 }
2199 // In a constructor body,
2200 // if symbol is a field or instance method, check that it is
2201 // not accessed before the supertype constructor is called.
2202 if ((symEnv.info.isSelfCall || noOuterThisPath) &&
2203 (sym.kind & (VAR | MTH)) != 0 &&
2204 sym.owner.kind == TYP &&
2205 (sym.flags() & STATIC) == 0) {
2206 chk.earlyRefError(tree.pos(), sym.kind == VAR ? sym : thisSym(tree.pos(), env));
2207 }
2208 Env<AttrContext> env1 = env;
2209 if (sym.kind != ERR && sym.kind != TYP && sym.owner != null && sym.owner != env1.enclClass.sym) {
2210 // If the found symbol is inaccessible, then it is
2211 // accessed through an enclosing instance. Locate this
2212 // enclosing instance:
2213 while (env1.outer != null && !rs.isAccessible(env, env1.enclClass.sym.type, sym))
2214 env1 = env1.outer;
2215 }
2216 result = checkId(tree, env1.enclClass.sym.type, sym, env, pkind, pt, varArgs);
2217 }
2219 public void visitSelect(JCFieldAccess tree) {
2220 // Determine the expected kind of the qualifier expression.
2221 int skind = 0;
2222 if (tree.name == names._this || tree.name == names._super ||
2223 tree.name == names._class)
2224 {
2225 skind = TYP;
2226 } else {
2227 if ((pkind & PCK) != 0) skind = skind | PCK;
2228 if ((pkind & TYP) != 0) skind = skind | TYP | PCK;
2229 if ((pkind & (VAL | MTH)) != 0) skind = skind | VAL | TYP;
2230 }
2232 // Attribute the qualifier expression, and determine its symbol (if any).
2233 Type site = attribTree(tree.selected, env, skind, Infer.anyPoly);
2234 if ((pkind & (PCK | TYP)) == 0)
2235 site = capture(site); // Capture field access
2237 // don't allow T.class T[].class, etc
2238 if (skind == TYP) {
2239 Type elt = site;
2240 while (elt.tag == ARRAY)
2241 elt = ((ArrayType)elt).elemtype;
2242 if (elt.tag == TYPEVAR) {
2243 log.error(tree.pos(), "type.var.cant.be.deref");
2244 result = types.createErrorType(tree.type);
2245 return;
2246 }
2247 }
2249 // If qualifier symbol is a type or `super', assert `selectSuper'
2250 // for the selection. This is relevant for determining whether
2251 // protected symbols are accessible.
2252 Symbol sitesym = TreeInfo.symbol(tree.selected);
2253 boolean selectSuperPrev = env.info.selectSuper;
2254 env.info.selectSuper =
2255 sitesym != null &&
2256 sitesym.name == names._super;
2258 // If selected expression is polymorphic, strip
2259 // type parameters and remember in env.info.tvars, so that
2260 // they can be added later (in Attr.checkId and Infer.instantiateMethod).
2261 if (tree.selected.type.tag == FORALL) {
2262 ForAll pstype = (ForAll)tree.selected.type;
2263 env.info.tvars = pstype.tvars;
2264 site = tree.selected.type = pstype.qtype;
2265 }
2267 // Determine the symbol represented by the selection.
2268 env.info.varArgs = false;
2269 Symbol sym = selectSym(tree, sitesym, site, env, pt, pkind);
2270 if (sym.exists() && !isType(sym) && (pkind & (PCK | TYP)) != 0) {
2271 site = capture(site);
2272 sym = selectSym(tree, sitesym, site, env, pt, pkind);
2273 }
2274 boolean varArgs = env.info.varArgs;
2275 tree.sym = sym;
2277 if (site.tag == TYPEVAR && !isType(sym) && sym.kind != ERR) {
2278 while (site.tag == TYPEVAR) site = site.getUpperBound();
2279 site = capture(site);
2280 }
2282 // If that symbol is a variable, ...
2283 if (sym.kind == VAR) {
2284 VarSymbol v = (VarSymbol)sym;
2286 // ..., evaluate its initializer, if it has one, and check for
2287 // illegal forward reference.
2288 checkInit(tree, env, v, true);
2290 // If we are expecting a variable (as opposed to a value), check
2291 // that the variable is assignable in the current environment.
2292 if (pkind == VAR)
2293 checkAssignable(tree.pos(), v, tree.selected, env);
2294 }
2296 if (sitesym != null &&
2297 sitesym.kind == VAR &&
2298 ((VarSymbol)sitesym).isResourceVariable() &&
2299 sym.kind == MTH &&
2300 sym.overrides(syms.autoCloseableClose, sitesym.type.tsym, types, true) &&
2301 env.info.lint.isEnabled(LintCategory.TRY)) {
2302 log.warning(LintCategory.TRY, tree, "try.explicit.close.call");
2303 }
2305 // Disallow selecting a type from an expression
2306 if (isType(sym) && (sitesym==null || (sitesym.kind&(TYP|PCK)) == 0)) {
2307 tree.type = check(tree.selected, pt,
2308 sitesym == null ? VAL : sitesym.kind, TYP|PCK, pt);
2309 }
2311 if (isType(sitesym)) {
2312 if (sym.name == names._this) {
2313 // If `C' is the currently compiled class, check that
2314 // C.this' does not appear in a call to a super(...)
2315 if (env.info.isSelfCall &&
2316 site.tsym == env.enclClass.sym) {
2317 chk.earlyRefError(tree.pos(), sym);
2318 }
2319 } else {
2320 // Check if type-qualified fields or methods are static (JLS)
2321 if ((sym.flags() & STATIC) == 0 &&
2322 sym.name != names._super &&
2323 (sym.kind == VAR || sym.kind == MTH)) {
2324 rs.access(rs.new StaticError(sym),
2325 tree.pos(), site, sym.name, true);
2326 }
2327 }
2328 } else if (sym.kind != ERR && (sym.flags() & STATIC) != 0 && sym.name != names._class) {
2329 // If the qualified item is not a type and the selected item is static, report
2330 // a warning. Make allowance for the class of an array type e.g. Object[].class)
2331 chk.warnStatic(tree, "static.not.qualified.by.type", Kinds.kindName(sym.kind), sym.owner);
2332 }
2334 // If we are selecting an instance member via a `super', ...
2335 if (env.info.selectSuper && (sym.flags() & STATIC) == 0) {
2337 // Check that super-qualified symbols are not abstract (JLS)
2338 rs.checkNonAbstract(tree.pos(), sym);
2340 if (site.isRaw()) {
2341 // Determine argument types for site.
2342 Type site1 = types.asSuper(env.enclClass.sym.type, site.tsym);
2343 if (site1 != null) site = site1;
2344 }
2345 }
2347 env.info.selectSuper = selectSuperPrev;
2348 result = checkId(tree, site, sym, env, pkind, pt, varArgs);
2349 env.info.tvars = List.nil();
2350 }
2351 //where
2352 /** Determine symbol referenced by a Select expression,
2353 *
2354 * @param tree The select tree.
2355 * @param site The type of the selected expression,
2356 * @param env The current environment.
2357 * @param pt The current prototype.
2358 * @param pkind The expected kind(s) of the Select expression.
2359 */
2360 private Symbol selectSym(JCFieldAccess tree,
2361 Type site,
2362 Env<AttrContext> env,
2363 Type pt,
2364 int pkind) {
2365 return selectSym(tree, site.tsym, site, env, pt, pkind);
2366 }
2367 private Symbol selectSym(JCFieldAccess tree,
2368 Symbol location,
2369 Type site,
2370 Env<AttrContext> env,
2371 Type pt,
2372 int pkind) {
2373 DiagnosticPosition pos = tree.pos();
2374 Name name = tree.name;
2376 switch (site.tag) {
2377 case PACKAGE:
2378 return rs.access(
2379 rs.findIdentInPackage(env, site.tsym, name, pkind),
2380 pos, location, site, name, true);
2381 case ARRAY:
2382 case CLASS:
2383 if (pt.tag == METHOD || pt.tag == FORALL) {
2384 return rs.resolveQualifiedMethod(
2385 pos, env, location, site, name, pt.getParameterTypes(), pt.getTypeArguments());
2386 } else if (name == names._this || name == names._super) {
2387 return rs.resolveSelf(pos, env, site.tsym, name);
2388 } else if (name == names._class) {
2389 // In this case, we have already made sure in
2390 // visitSelect that qualifier expression is a type.
2391 Type t = syms.classType;
2392 List<Type> typeargs = allowGenerics
2393 ? List.of(types.erasure(site))
2394 : List.<Type>nil();
2395 t = new ClassType(t.getEnclosingType(), typeargs, t.tsym);
2396 return new VarSymbol(
2397 STATIC | PUBLIC | FINAL, names._class, t, site.tsym);
2398 } else {
2399 // We are seeing a plain identifier as selector.
2400 Symbol sym = rs.findIdentInType(env, site, name, pkind);
2401 if ((pkind & ERRONEOUS) == 0)
2402 sym = rs.access(sym, pos, location, site, name, true);
2403 return sym;
2404 }
2405 case WILDCARD:
2406 throw new AssertionError(tree);
2407 case TYPEVAR:
2408 // Normally, site.getUpperBound() shouldn't be null.
2409 // It should only happen during memberEnter/attribBase
2410 // when determining the super type which *must* beac
2411 // done before attributing the type variables. In
2412 // other words, we are seeing this illegal program:
2413 // class B<T> extends A<T.foo> {}
2414 Symbol sym = (site.getUpperBound() != null)
2415 ? selectSym(tree, location, capture(site.getUpperBound()), env, pt, pkind)
2416 : null;
2417 if (sym == null) {
2418 log.error(pos, "type.var.cant.be.deref");
2419 return syms.errSymbol;
2420 } else {
2421 Symbol sym2 = (sym.flags() & Flags.PRIVATE) != 0 ?
2422 rs.new AccessError(env, site, sym) :
2423 sym;
2424 rs.access(sym2, pos, location, site, name, true);
2425 return sym;
2426 }
2427 case ERROR:
2428 // preserve identifier names through errors
2429 return types.createErrorType(name, site.tsym, site).tsym;
2430 default:
2431 // The qualifier expression is of a primitive type -- only
2432 // .class is allowed for these.
2433 if (name == names._class) {
2434 // In this case, we have already made sure in Select that
2435 // qualifier expression is a type.
2436 Type t = syms.classType;
2437 Type arg = types.boxedClass(site).type;
2438 t = new ClassType(t.getEnclosingType(), List.of(arg), t.tsym);
2439 return new VarSymbol(
2440 STATIC | PUBLIC | FINAL, names._class, t, site.tsym);
2441 } else {
2442 log.error(pos, "cant.deref", site);
2443 return syms.errSymbol;
2444 }
2445 }
2446 }
2448 /** Determine type of identifier or select expression and check that
2449 * (1) the referenced symbol is not deprecated
2450 * (2) the symbol's type is safe (@see checkSafe)
2451 * (3) if symbol is a variable, check that its type and kind are
2452 * compatible with the prototype and protokind.
2453 * (4) if symbol is an instance field of a raw type,
2454 * which is being assigned to, issue an unchecked warning if its
2455 * type changes under erasure.
2456 * (5) if symbol is an instance method of a raw type, issue an
2457 * unchecked warning if its argument types change under erasure.
2458 * If checks succeed:
2459 * If symbol is a constant, return its constant type
2460 * else if symbol is a method, return its result type
2461 * otherwise return its type.
2462 * Otherwise return errType.
2463 *
2464 * @param tree The syntax tree representing the identifier
2465 * @param site If this is a select, the type of the selected
2466 * expression, otherwise the type of the current class.
2467 * @param sym The symbol representing the identifier.
2468 * @param env The current environment.
2469 * @param pkind The set of expected kinds.
2470 * @param pt The expected type.
2471 */
2472 Type checkId(JCTree tree,
2473 Type site,
2474 Symbol sym,
2475 Env<AttrContext> env,
2476 int pkind,
2477 Type pt,
2478 boolean useVarargs) {
2479 if (pt.isErroneous()) return types.createErrorType(site);
2480 Type owntype; // The computed type of this identifier occurrence.
2481 switch (sym.kind) {
2482 case TYP:
2483 // For types, the computed type equals the symbol's type,
2484 // except for two situations:
2485 owntype = sym.type;
2486 if (owntype.tag == CLASS) {
2487 Type ownOuter = owntype.getEnclosingType();
2489 // (a) If the symbol's type is parameterized, erase it
2490 // because no type parameters were given.
2491 // We recover generic outer type later in visitTypeApply.
2492 if (owntype.tsym.type.getTypeArguments().nonEmpty()) {
2493 owntype = types.erasure(owntype);
2494 }
2496 // (b) If the symbol's type is an inner class, then
2497 // we have to interpret its outer type as a superclass
2498 // of the site type. Example:
2499 //
2500 // class Tree<A> { class Visitor { ... } }
2501 // class PointTree extends Tree<Point> { ... }
2502 // ...PointTree.Visitor...
2503 //
2504 // Then the type of the last expression above is
2505 // Tree<Point>.Visitor.
2506 else if (ownOuter.tag == CLASS && site != ownOuter) {
2507 Type normOuter = site;
2508 if (normOuter.tag == CLASS)
2509 normOuter = types.asEnclosingSuper(site, ownOuter.tsym);
2510 if (normOuter == null) // perhaps from an import
2511 normOuter = types.erasure(ownOuter);
2512 if (normOuter != ownOuter)
2513 owntype = new ClassType(
2514 normOuter, List.<Type>nil(), owntype.tsym);
2515 }
2516 }
2517 break;
2518 case VAR:
2519 VarSymbol v = (VarSymbol)sym;
2520 // Test (4): if symbol is an instance field of a raw type,
2521 // which is being assigned to, issue an unchecked warning if
2522 // its type changes under erasure.
2523 if (allowGenerics &&
2524 pkind == VAR &&
2525 v.owner.kind == TYP &&
2526 (v.flags() & STATIC) == 0 &&
2527 (site.tag == CLASS || site.tag == TYPEVAR)) {
2528 Type s = types.asOuterSuper(site, v.owner);
2529 if (s != null &&
2530 s.isRaw() &&
2531 !types.isSameType(v.type, v.erasure(types))) {
2532 chk.warnUnchecked(tree.pos(),
2533 "unchecked.assign.to.var",
2534 v, s);
2535 }
2536 }
2537 // The computed type of a variable is the type of the
2538 // variable symbol, taken as a member of the site type.
2539 owntype = (sym.owner.kind == TYP &&
2540 sym.name != names._this && sym.name != names._super)
2541 ? types.memberType(site, sym)
2542 : sym.type;
2544 if (env.info.tvars.nonEmpty()) {
2545 Type owntype1 = new ForAll(env.info.tvars, owntype);
2546 for (List<Type> l = env.info.tvars; l.nonEmpty(); l = l.tail)
2547 if (!owntype.contains(l.head)) {
2548 log.error(tree.pos(), "undetermined.type", owntype1);
2549 owntype1 = types.createErrorType(owntype1);
2550 }
2551 owntype = owntype1;
2552 }
2554 // If the variable is a constant, record constant value in
2555 // computed type.
2556 if (v.getConstValue() != null && isStaticReference(tree))
2557 owntype = owntype.constType(v.getConstValue());
2559 if (pkind == VAL) {
2560 owntype = capture(owntype); // capture "names as expressions"
2561 }
2562 break;
2563 case MTH: {
2564 JCMethodInvocation app = (JCMethodInvocation)env.tree;
2565 owntype = checkMethod(site, sym, env, app.args,
2566 pt.getParameterTypes(), pt.getTypeArguments(),
2567 env.info.varArgs);
2568 break;
2569 }
2570 case PCK: case ERR:
2571 owntype = sym.type;
2572 break;
2573 default:
2574 throw new AssertionError("unexpected kind: " + sym.kind +
2575 " in tree " + tree);
2576 }
2578 // Test (1): emit a `deprecation' warning if symbol is deprecated.
2579 // (for constructors, the error was given when the constructor was
2580 // resolved)
2581 if (sym.name != names.init &&
2582 (sym.flags() & DEPRECATED) != 0 &&
2583 (env.info.scope.owner.flags() & DEPRECATED) == 0 &&
2584 sym.outermostClass() != env.info.scope.owner.outermostClass())
2585 chk.warnDeprecated(tree.pos(), sym);
2587 if ((sym.flags() & PROPRIETARY) != 0) {
2588 if (enableSunApiLintControl)
2589 chk.warnSunApi(tree.pos(), "sun.proprietary", sym);
2590 else
2591 log.strictWarning(tree.pos(), "sun.proprietary", sym);
2592 }
2594 // Test (3): if symbol is a variable, check that its type and
2595 // kind are compatible with the prototype and protokind.
2596 return check(tree, owntype, sym.kind, pkind, pt);
2597 }
2599 /** Check that variable is initialized and evaluate the variable's
2600 * initializer, if not yet done. Also check that variable is not
2601 * referenced before it is defined.
2602 * @param tree The tree making up the variable reference.
2603 * @param env The current environment.
2604 * @param v The variable's symbol.
2605 */
2606 private void checkInit(JCTree tree,
2607 Env<AttrContext> env,
2608 VarSymbol v,
2609 boolean onlyWarning) {
2610 // System.err.println(v + " " + ((v.flags() & STATIC) != 0) + " " +
2611 // tree.pos + " " + v.pos + " " +
2612 // Resolve.isStatic(env));//DEBUG
2614 // A forward reference is diagnosed if the declaration position
2615 // of the variable is greater than the current tree position
2616 // and the tree and variable definition occur in the same class
2617 // definition. Note that writes don't count as references.
2618 // This check applies only to class and instance
2619 // variables. Local variables follow different scope rules,
2620 // and are subject to definite assignment checking.
2621 if ((env.info.enclVar == v || v.pos > tree.pos) &&
2622 v.owner.kind == TYP &&
2623 canOwnInitializer(env.info.scope.owner) &&
2624 v.owner == env.info.scope.owner.enclClass() &&
2625 ((v.flags() & STATIC) != 0) == Resolve.isStatic(env) &&
2626 (env.tree.getTag() != JCTree.ASSIGN ||
2627 TreeInfo.skipParens(((JCAssign) env.tree).lhs) != tree)) {
2628 String suffix = (env.info.enclVar == v) ?
2629 "self.ref" : "forward.ref";
2630 if (!onlyWarning || isStaticEnumField(v)) {
2631 log.error(tree.pos(), "illegal." + suffix);
2632 } else if (useBeforeDeclarationWarning) {
2633 log.warning(tree.pos(), suffix, v);
2634 }
2635 }
2637 v.getConstValue(); // ensure initializer is evaluated
2639 checkEnumInitializer(tree, env, v);
2640 }
2642 /**
2643 * Check for illegal references to static members of enum. In
2644 * an enum type, constructors and initializers may not
2645 * reference its static members unless they are constant.
2646 *
2647 * @param tree The tree making up the variable reference.
2648 * @param env The current environment.
2649 * @param v The variable's symbol.
2650 * @see JLS 3rd Ed. (8.9 Enums)
2651 */
2652 private void checkEnumInitializer(JCTree tree, Env<AttrContext> env, VarSymbol v) {
2653 // JLS 3rd Ed.:
2654 //
2655 // "It is a compile-time error to reference a static field
2656 // of an enum type that is not a compile-time constant
2657 // (15.28) from constructors, instance initializer blocks,
2658 // or instance variable initializer expressions of that
2659 // type. It is a compile-time error for the constructors,
2660 // instance initializer blocks, or instance variable
2661 // initializer expressions of an enum constant e to refer
2662 // to itself or to an enum constant of the same type that
2663 // is declared to the right of e."
2664 if (isStaticEnumField(v)) {
2665 ClassSymbol enclClass = env.info.scope.owner.enclClass();
2667 if (enclClass == null || enclClass.owner == null)
2668 return;
2670 // See if the enclosing class is the enum (or a
2671 // subclass thereof) declaring v. If not, this
2672 // reference is OK.
2673 if (v.owner != enclClass && !types.isSubtype(enclClass.type, v.owner.type))
2674 return;
2676 // If the reference isn't from an initializer, then
2677 // the reference is OK.
2678 if (!Resolve.isInitializer(env))
2679 return;
2681 log.error(tree.pos(), "illegal.enum.static.ref");
2682 }
2683 }
2685 /** Is the given symbol a static, non-constant field of an Enum?
2686 * Note: enum literals should not be regarded as such
2687 */
2688 private boolean isStaticEnumField(VarSymbol v) {
2689 return Flags.isEnum(v.owner) &&
2690 Flags.isStatic(v) &&
2691 !Flags.isConstant(v) &&
2692 v.name != names._class;
2693 }
2695 /** Can the given symbol be the owner of code which forms part
2696 * if class initialization? This is the case if the symbol is
2697 * a type or field, or if the symbol is the synthetic method.
2698 * owning a block.
2699 */
2700 private boolean canOwnInitializer(Symbol sym) {
2701 return
2702 (sym.kind & (VAR | TYP)) != 0 ||
2703 (sym.kind == MTH && (sym.flags() & BLOCK) != 0);
2704 }
2706 Warner noteWarner = new Warner();
2708 /**
2709 * Check that method arguments conform to its instantation.
2710 **/
2711 public Type checkMethod(Type site,
2712 Symbol sym,
2713 Env<AttrContext> env,
2714 final List<JCExpression> argtrees,
2715 List<Type> argtypes,
2716 List<Type> typeargtypes,
2717 boolean useVarargs) {
2718 // Test (5): if symbol is an instance method of a raw type, issue
2719 // an unchecked warning if its argument types change under erasure.
2720 if (allowGenerics &&
2721 (sym.flags() & STATIC) == 0 &&
2722 (site.tag == CLASS || site.tag == TYPEVAR)) {
2723 Type s = types.asOuterSuper(site, sym.owner);
2724 if (s != null && s.isRaw() &&
2725 !types.isSameTypes(sym.type.getParameterTypes(),
2726 sym.erasure(types).getParameterTypes())) {
2727 chk.warnUnchecked(env.tree.pos(),
2728 "unchecked.call.mbr.of.raw.type",
2729 sym, s);
2730 }
2731 }
2733 // Compute the identifier's instantiated type.
2734 // For methods, we need to compute the instance type by
2735 // Resolve.instantiate from the symbol's type as well as
2736 // any type arguments and value arguments.
2737 noteWarner.clear();
2738 Type owntype = rs.instantiate(env,
2739 site,
2740 sym,
2741 argtypes,
2742 typeargtypes,
2743 true,
2744 useVarargs,
2745 noteWarner);
2746 boolean warned = noteWarner.hasNonSilentLint(LintCategory.UNCHECKED);
2748 // If this fails, something went wrong; we should not have
2749 // found the identifier in the first place.
2750 if (owntype == null) {
2751 if (!pt.isErroneous())
2752 log.error(env.tree.pos(),
2753 "internal.error.cant.instantiate",
2754 sym, site,
2755 Type.toString(pt.getParameterTypes()));
2756 owntype = types.createErrorType(site);
2757 } else {
2758 // System.out.println("call : " + env.tree);
2759 // System.out.println("method : " + owntype);
2760 // System.out.println("actuals: " + argtypes);
2761 List<Type> formals = owntype.getParameterTypes();
2762 Type last = useVarargs ? formals.last() : null;
2763 if (sym.name==names.init &&
2764 sym.owner == syms.enumSym)
2765 formals = formals.tail.tail;
2766 List<JCExpression> args = argtrees;
2767 while (formals.head != last) {
2768 JCTree arg = args.head;
2769 Warner warn = chk.convertWarner(arg.pos(), arg.type, formals.head);
2770 assertConvertible(arg, arg.type, formals.head, warn);
2771 warned |= warn.hasNonSilentLint(LintCategory.UNCHECKED);
2772 args = args.tail;
2773 formals = formals.tail;
2774 }
2775 if (useVarargs) {
2776 Type varArg = types.elemtype(last);
2777 while (args.tail != null) {
2778 JCTree arg = args.head;
2779 Warner warn = chk.convertWarner(arg.pos(), arg.type, varArg);
2780 assertConvertible(arg, arg.type, varArg, warn);
2781 warned |= warn.hasNonSilentLint(LintCategory.UNCHECKED);
2782 args = args.tail;
2783 }
2784 } else if ((sym.flags() & VARARGS) != 0 && allowVarargs) {
2785 // non-varargs call to varargs method
2786 Type varParam = owntype.getParameterTypes().last();
2787 Type lastArg = argtypes.last();
2788 if (types.isSubtypeUnchecked(lastArg, types.elemtype(varParam)) &&
2789 !types.isSameType(types.erasure(varParam), types.erasure(lastArg)))
2790 log.warning(argtrees.last().pos(), "inexact.non-varargs.call",
2791 types.elemtype(varParam),
2792 varParam);
2793 }
2795 if (warned && sym.type.tag == FORALL) {
2796 chk.warnUnchecked(env.tree.pos(),
2797 "unchecked.meth.invocation.applied",
2798 kindName(sym),
2799 sym.name,
2800 rs.methodArguments(sym.type.getParameterTypes()),
2801 rs.methodArguments(argtypes),
2802 kindName(sym.location()),
2803 sym.location());
2804 owntype = new MethodType(owntype.getParameterTypes(),
2805 types.erasure(owntype.getReturnType()),
2806 owntype.getThrownTypes(),
2807 syms.methodClass);
2808 }
2809 if (useVarargs) {
2810 JCTree tree = env.tree;
2811 Type argtype = owntype.getParameterTypes().last();
2812 if (owntype.getReturnType().tag != FORALL || warned) {
2813 chk.checkVararg(env.tree.pos(), owntype.getParameterTypes(), sym);
2814 }
2815 Type elemtype = types.elemtype(argtype);
2816 switch (tree.getTag()) {
2817 case JCTree.APPLY:
2818 ((JCMethodInvocation) tree).varargsElement = elemtype;
2819 break;
2820 case JCTree.NEWCLASS:
2821 ((JCNewClass) tree).varargsElement = elemtype;
2822 break;
2823 default:
2824 throw new AssertionError(""+tree);
2825 }
2826 }
2827 }
2828 return owntype;
2829 }
2831 private void assertConvertible(JCTree tree, Type actual, Type formal, Warner warn) {
2832 if (types.isConvertible(actual, formal, warn))
2833 return;
2835 if (formal.isCompound()
2836 && types.isSubtype(actual, types.supertype(formal))
2837 && types.isSubtypeUnchecked(actual, types.interfaces(formal), warn))
2838 return;
2840 if (false) {
2841 // TODO: make assertConvertible work
2842 chk.typeError(tree.pos(), diags.fragment("incompatible.types"), actual, formal);
2843 throw new AssertionError("Tree: " + tree
2844 + " actual:" + actual
2845 + " formal: " + formal);
2846 }
2847 }
2849 public void visitLiteral(JCLiteral tree) {
2850 result = check(
2851 tree, litType(tree.typetag).constType(tree.value), VAL, pkind, pt);
2852 }
2853 //where
2854 /** Return the type of a literal with given type tag.
2855 */
2856 Type litType(int tag) {
2857 return (tag == TypeTags.CLASS) ? syms.stringType : syms.typeOfTag[tag];
2858 }
2860 public void visitTypeIdent(JCPrimitiveTypeTree tree) {
2861 result = check(tree, syms.typeOfTag[tree.typetag], TYP, pkind, pt);
2862 }
2864 public void visitTypeArray(JCArrayTypeTree tree) {
2865 Type etype = attribType(tree.elemtype, env);
2866 Type type = new ArrayType(etype, syms.arrayClass);
2867 result = check(tree, type, TYP, pkind, pt);
2868 }
2870 /** Visitor method for parameterized types.
2871 * Bound checking is left until later, since types are attributed
2872 * before supertype structure is completely known
2873 */
2874 public void visitTypeApply(JCTypeApply tree) {
2875 Type owntype = types.createErrorType(tree.type);
2877 // Attribute functor part of application and make sure it's a class.
2878 Type clazztype = chk.checkClassType(tree.clazz.pos(), attribType(tree.clazz, env));
2880 // Attribute type parameters
2881 List<Type> actuals = attribTypes(tree.arguments, env);
2883 if (clazztype.tag == CLASS) {
2884 List<Type> formals = clazztype.tsym.type.getTypeArguments();
2886 if (actuals.length() == formals.length() || actuals.length() == 0) {
2887 List<Type> a = actuals;
2888 List<Type> f = formals;
2889 while (a.nonEmpty()) {
2890 a.head = a.head.withTypeVar(f.head);
2891 a = a.tail;
2892 f = f.tail;
2893 }
2894 // Compute the proper generic outer
2895 Type clazzOuter = clazztype.getEnclosingType();
2896 if (clazzOuter.tag == CLASS) {
2897 Type site;
2898 JCExpression clazz = TreeInfo.typeIn(tree.clazz);
2899 if (clazz.getTag() == JCTree.IDENT) {
2900 site = env.enclClass.sym.type;
2901 } else if (clazz.getTag() == JCTree.SELECT) {
2902 site = ((JCFieldAccess) clazz).selected.type;
2903 } else throw new AssertionError(""+tree);
2904 if (clazzOuter.tag == CLASS && site != clazzOuter) {
2905 if (site.tag == CLASS)
2906 site = types.asOuterSuper(site, clazzOuter.tsym);
2907 if (site == null)
2908 site = types.erasure(clazzOuter);
2909 clazzOuter = site;
2910 }
2911 }
2912 owntype = new ClassType(clazzOuter, actuals, clazztype.tsym);
2913 } else {
2914 if (formals.length() != 0) {
2915 log.error(tree.pos(), "wrong.number.type.args",
2916 Integer.toString(formals.length()));
2917 } else {
2918 log.error(tree.pos(), "type.doesnt.take.params", clazztype.tsym);
2919 }
2920 owntype = types.createErrorType(tree.type);
2921 }
2922 }
2923 result = check(tree, owntype, TYP, pkind, pt);
2924 }
2926 public void visitTypeDisjunction(JCTypeDisjunction tree) {
2927 ListBuffer<Type> multicatchTypes = ListBuffer.lb();
2928 for (JCExpression typeTree : tree.alternatives) {
2929 Type ctype = attribType(typeTree, env);
2930 ctype = chk.checkType(typeTree.pos(),
2931 chk.checkClassType(typeTree.pos(), ctype),
2932 syms.throwableType);
2933 multicatchTypes.append(ctype);
2934 }
2935 tree.type = result = check(tree, types.lub(multicatchTypes.toList()), TYP, pkind, pt);
2936 }
2938 public void visitTypeParameter(JCTypeParameter tree) {
2939 TypeVar a = (TypeVar)tree.type;
2940 Set<Type> boundSet = new HashSet<Type>();
2941 if (a.bound.isErroneous())
2942 return;
2943 List<Type> bs = types.getBounds(a);
2944 if (tree.bounds.nonEmpty()) {
2945 // accept class or interface or typevar as first bound.
2946 Type b = checkBase(bs.head, tree.bounds.head, env, false, false, false);
2947 boundSet.add(types.erasure(b));
2948 if (b.isErroneous()) {
2949 a.bound = b;
2950 }
2951 else if (b.tag == TYPEVAR) {
2952 // if first bound was a typevar, do not accept further bounds.
2953 if (tree.bounds.tail.nonEmpty()) {
2954 log.error(tree.bounds.tail.head.pos(),
2955 "type.var.may.not.be.followed.by.other.bounds");
2956 tree.bounds = List.of(tree.bounds.head);
2957 a.bound = bs.head;
2958 }
2959 } else {
2960 // if first bound was a class or interface, accept only interfaces
2961 // as further bounds.
2962 for (JCExpression bound : tree.bounds.tail) {
2963 bs = bs.tail;
2964 Type i = checkBase(bs.head, bound, env, false, true, false);
2965 if (i.isErroneous())
2966 a.bound = i;
2967 else if (i.tag == CLASS)
2968 chk.checkNotRepeated(bound.pos(), types.erasure(i), boundSet);
2969 }
2970 }
2971 }
2972 bs = types.getBounds(a);
2974 // in case of multiple bounds ...
2975 if (bs.length() > 1) {
2976 // ... the variable's bound is a class type flagged COMPOUND
2977 // (see comment for TypeVar.bound).
2978 // In this case, generate a class tree that represents the
2979 // bound class, ...
2980 JCTree extending;
2981 List<JCExpression> implementing;
2982 if ((bs.head.tsym.flags() & INTERFACE) == 0) {
2983 extending = tree.bounds.head;
2984 implementing = tree.bounds.tail;
2985 } else {
2986 extending = null;
2987 implementing = tree.bounds;
2988 }
2989 JCClassDecl cd = make.at(tree.pos).ClassDef(
2990 make.Modifiers(PUBLIC | ABSTRACT),
2991 tree.name, List.<JCTypeParameter>nil(),
2992 extending, implementing, List.<JCTree>nil());
2994 ClassSymbol c = (ClassSymbol)a.getUpperBound().tsym;
2995 Assert.check((c.flags() & COMPOUND) != 0);
2996 cd.sym = c;
2997 c.sourcefile = env.toplevel.sourcefile;
2999 // ... and attribute the bound class
3000 c.flags_field |= UNATTRIBUTED;
3001 Env<AttrContext> cenv = enter.classEnv(cd, env);
3002 enter.typeEnvs.put(c, cenv);
3003 }
3004 }
3007 public void visitWildcard(JCWildcard tree) {
3008 //- System.err.println("visitWildcard("+tree+");");//DEBUG
3009 Type type = (tree.kind.kind == BoundKind.UNBOUND)
3010 ? syms.objectType
3011 : attribType(tree.inner, env);
3012 result = check(tree, new WildcardType(chk.checkRefType(tree.pos(), type),
3013 tree.kind.kind,
3014 syms.boundClass),
3015 TYP, pkind, pt);
3016 }
3018 public void visitAnnotation(JCAnnotation tree) {
3019 log.error(tree.pos(), "annotation.not.valid.for.type", pt);
3020 result = tree.type = syms.errType;
3021 }
3023 public void visitErroneous(JCErroneous tree) {
3024 if (tree.errs != null)
3025 for (JCTree err : tree.errs)
3026 attribTree(err, env, ERR, pt);
3027 result = tree.type = syms.errType;
3028 }
3030 /** Default visitor method for all other trees.
3031 */
3032 public void visitTree(JCTree tree) {
3033 throw new AssertionError();
3034 }
3036 /** Main method: attribute class definition associated with given class symbol.
3037 * reporting completion failures at the given position.
3038 * @param pos The source position at which completion errors are to be
3039 * reported.
3040 * @param c The class symbol whose definition will be attributed.
3041 */
3042 public void attribClass(DiagnosticPosition pos, ClassSymbol c) {
3043 try {
3044 annotate.flush();
3045 attribClass(c);
3046 } catch (CompletionFailure ex) {
3047 chk.completionError(pos, ex);
3048 }
3049 }
3051 /** Attribute class definition associated with given class symbol.
3052 * @param c The class symbol whose definition will be attributed.
3053 */
3054 void attribClass(ClassSymbol c) throws CompletionFailure {
3055 if (c.type.tag == ERROR) return;
3057 // Check for cycles in the inheritance graph, which can arise from
3058 // ill-formed class files.
3059 chk.checkNonCyclic(null, c.type);
3061 Type st = types.supertype(c.type);
3062 if ((c.flags_field & Flags.COMPOUND) == 0) {
3063 // First, attribute superclass.
3064 if (st.tag == CLASS)
3065 attribClass((ClassSymbol)st.tsym);
3067 // Next attribute owner, if it is a class.
3068 if (c.owner.kind == TYP && c.owner.type.tag == CLASS)
3069 attribClass((ClassSymbol)c.owner);
3070 }
3072 // The previous operations might have attributed the current class
3073 // if there was a cycle. So we test first whether the class is still
3074 // UNATTRIBUTED.
3075 if ((c.flags_field & UNATTRIBUTED) != 0) {
3076 c.flags_field &= ~UNATTRIBUTED;
3078 // Get environment current at the point of class definition.
3079 Env<AttrContext> env = enter.typeEnvs.get(c);
3081 // The info.lint field in the envs stored in enter.typeEnvs is deliberately uninitialized,
3082 // because the annotations were not available at the time the env was created. Therefore,
3083 // we look up the environment chain for the first enclosing environment for which the
3084 // lint value is set. Typically, this is the parent env, but might be further if there
3085 // are any envs created as a result of TypeParameter nodes.
3086 Env<AttrContext> lintEnv = env;
3087 while (lintEnv.info.lint == null)
3088 lintEnv = lintEnv.next;
3090 // Having found the enclosing lint value, we can initialize the lint value for this class
3091 env.info.lint = lintEnv.info.lint.augment(c.attributes_field, c.flags());
3093 Lint prevLint = chk.setLint(env.info.lint);
3094 JavaFileObject prev = log.useSource(c.sourcefile);
3096 try {
3097 // java.lang.Enum may not be subclassed by a non-enum
3098 if (st.tsym == syms.enumSym &&
3099 ((c.flags_field & (Flags.ENUM|Flags.COMPOUND)) == 0))
3100 log.error(env.tree.pos(), "enum.no.subclassing");
3102 // Enums may not be extended by source-level classes
3103 if (st.tsym != null &&
3104 ((st.tsym.flags_field & Flags.ENUM) != 0) &&
3105 ((c.flags_field & (Flags.ENUM | Flags.COMPOUND)) == 0) &&
3106 !target.compilerBootstrap(c)) {
3107 log.error(env.tree.pos(), "enum.types.not.extensible");
3108 }
3109 attribClassBody(env, c);
3111 chk.checkDeprecatedAnnotation(env.tree.pos(), c);
3112 } finally {
3113 log.useSource(prev);
3114 chk.setLint(prevLint);
3115 }
3117 }
3118 }
3120 public void visitImport(JCImport tree) {
3121 // nothing to do
3122 }
3124 /** Finish the attribution of a class. */
3125 private void attribClassBody(Env<AttrContext> env, ClassSymbol c) {
3126 JCClassDecl tree = (JCClassDecl)env.tree;
3127 Assert.check(c == tree.sym);
3129 // Validate annotations
3130 chk.validateAnnotations(tree.mods.annotations, c);
3132 // Validate type parameters, supertype and interfaces.
3133 attribBounds(tree.typarams);
3134 if (!c.isAnonymous()) {
3135 //already checked if anonymous
3136 chk.validate(tree.typarams, env);
3137 chk.validate(tree.extending, env);
3138 chk.validate(tree.implementing, env);
3139 }
3141 // If this is a non-abstract class, check that it has no abstract
3142 // methods or unimplemented methods of an implemented interface.
3143 if ((c.flags() & (ABSTRACT | INTERFACE)) == 0) {
3144 if (!relax)
3145 chk.checkAllDefined(tree.pos(), c);
3146 }
3148 if ((c.flags() & ANNOTATION) != 0) {
3149 if (tree.implementing.nonEmpty())
3150 log.error(tree.implementing.head.pos(),
3151 "cant.extend.intf.annotation");
3152 if (tree.typarams.nonEmpty())
3153 log.error(tree.typarams.head.pos(),
3154 "intf.annotation.cant.have.type.params");
3155 } else {
3156 // Check that all extended classes and interfaces
3157 // are compatible (i.e. no two define methods with same arguments
3158 // yet different return types). (JLS 8.4.6.3)
3159 chk.checkCompatibleSupertypes(tree.pos(), c.type);
3160 }
3162 // Check that class does not import the same parameterized interface
3163 // with two different argument lists.
3164 chk.checkClassBounds(tree.pos(), c.type);
3166 tree.type = c.type;
3168 for (List<JCTypeParameter> l = tree.typarams;
3169 l.nonEmpty(); l = l.tail) {
3170 Assert.checkNonNull(env.info.scope.lookup(l.head.name).scope);
3171 }
3173 // Check that a generic class doesn't extend Throwable
3174 if (!c.type.allparams().isEmpty() && types.isSubtype(c.type, syms.throwableType))
3175 log.error(tree.extending.pos(), "generic.throwable");
3177 // Check that all methods which implement some
3178 // method conform to the method they implement.
3179 chk.checkImplementations(tree);
3181 for (List<JCTree> l = tree.defs; l.nonEmpty(); l = l.tail) {
3182 // Attribute declaration
3183 attribStat(l.head, env);
3184 // Check that declarations in inner classes are not static (JLS 8.1.2)
3185 // Make an exception for static constants.
3186 if (c.owner.kind != PCK &&
3187 ((c.flags() & STATIC) == 0 || c.name == names.empty) &&
3188 (TreeInfo.flags(l.head) & (STATIC | INTERFACE)) != 0) {
3189 Symbol sym = null;
3190 if (l.head.getTag() == JCTree.VARDEF) sym = ((JCVariableDecl) l.head).sym;
3191 if (sym == null ||
3192 sym.kind != VAR ||
3193 ((VarSymbol) sym).getConstValue() == null)
3194 log.error(l.head.pos(), "icls.cant.have.static.decl", sym.location());
3195 }
3196 }
3198 // Check for cycles among non-initial constructors.
3199 chk.checkCyclicConstructors(tree);
3201 // Check for cycles among annotation elements.
3202 chk.checkNonCyclicElements(tree);
3204 // Check for proper use of serialVersionUID
3205 if (env.info.lint.isEnabled(LintCategory.SERIAL) &&
3206 isSerializable(c) &&
3207 (c.flags() & Flags.ENUM) == 0 &&
3208 (c.flags() & ABSTRACT) == 0) {
3209 checkSerialVersionUID(tree, c);
3210 }
3211 }
3212 // where
3213 /** check if a class is a subtype of Serializable, if that is available. */
3214 private boolean isSerializable(ClassSymbol c) {
3215 try {
3216 syms.serializableType.complete();
3217 }
3218 catch (CompletionFailure e) {
3219 return false;
3220 }
3221 return types.isSubtype(c.type, syms.serializableType);
3222 }
3224 /** Check that an appropriate serialVersionUID member is defined. */
3225 private void checkSerialVersionUID(JCClassDecl tree, ClassSymbol c) {
3227 // check for presence of serialVersionUID
3228 Scope.Entry e = c.members().lookup(names.serialVersionUID);
3229 while (e.scope != null && e.sym.kind != VAR) e = e.next();
3230 if (e.scope == null) {
3231 log.warning(LintCategory.SERIAL,
3232 tree.pos(), "missing.SVUID", c);
3233 return;
3234 }
3236 // check that it is static final
3237 VarSymbol svuid = (VarSymbol)e.sym;
3238 if ((svuid.flags() & (STATIC | FINAL)) !=
3239 (STATIC | FINAL))
3240 log.warning(LintCategory.SERIAL,
3241 TreeInfo.diagnosticPositionFor(svuid, tree), "improper.SVUID", c);
3243 // check that it is long
3244 else if (svuid.type.tag != TypeTags.LONG)
3245 log.warning(LintCategory.SERIAL,
3246 TreeInfo.diagnosticPositionFor(svuid, tree), "long.SVUID", c);
3248 // check constant
3249 else if (svuid.getConstValue() == null)
3250 log.warning(LintCategory.SERIAL,
3251 TreeInfo.diagnosticPositionFor(svuid, tree), "constant.SVUID", c);
3252 }
3254 private Type capture(Type type) {
3255 return types.capture(type);
3256 }
3258 // <editor-fold desc="post-attribution visitor">
3260 /**
3261 * Handle missing types/symbols in an AST. This routine is useful when
3262 * the compiler has encountered some errors (which might have ended up
3263 * terminating attribution abruptly); if the compiler is used in fail-over
3264 * mode (e.g. by an IDE) and the AST contains semantic errors, this routine
3265 * prevents NPE to be progagated during subsequent compilation steps.
3266 */
3267 public void postAttr(Env<AttrContext> env) {
3268 new PostAttrAnalyzer().scan(env.tree);
3269 }
3271 class PostAttrAnalyzer extends TreeScanner {
3273 private void initTypeIfNeeded(JCTree that) {
3274 if (that.type == null) {
3275 that.type = syms.unknownType;
3276 }
3277 }
3279 @Override
3280 public void scan(JCTree tree) {
3281 if (tree == null) return;
3282 if (tree instanceof JCExpression) {
3283 initTypeIfNeeded(tree);
3284 }
3285 super.scan(tree);
3286 }
3288 @Override
3289 public void visitIdent(JCIdent that) {
3290 if (that.sym == null) {
3291 that.sym = syms.unknownSymbol;
3292 }
3293 }
3295 @Override
3296 public void visitSelect(JCFieldAccess that) {
3297 if (that.sym == null) {
3298 that.sym = syms.unknownSymbol;
3299 }
3300 super.visitSelect(that);
3301 }
3303 @Override
3304 public void visitClassDef(JCClassDecl that) {
3305 initTypeIfNeeded(that);
3306 if (that.sym == null) {
3307 that.sym = new ClassSymbol(0, that.name, that.type, syms.noSymbol);
3308 }
3309 super.visitClassDef(that);
3310 }
3312 @Override
3313 public void visitMethodDef(JCMethodDecl that) {
3314 initTypeIfNeeded(that);
3315 if (that.sym == null) {
3316 that.sym = new MethodSymbol(0, that.name, that.type, syms.noSymbol);
3317 }
3318 super.visitMethodDef(that);
3319 }
3321 @Override
3322 public void visitVarDef(JCVariableDecl that) {
3323 initTypeIfNeeded(that);
3324 if (that.sym == null) {
3325 that.sym = new VarSymbol(0, that.name, that.type, syms.noSymbol);
3326 that.sym.adr = 0;
3327 }
3328 super.visitVarDef(that);
3329 }
3331 @Override
3332 public void visitNewClass(JCNewClass that) {
3333 if (that.constructor == null) {
3334 that.constructor = new MethodSymbol(0, names.init, syms.unknownType, syms.noSymbol);
3335 }
3336 if (that.constructorType == null) {
3337 that.constructorType = syms.unknownType;
3338 }
3339 super.visitNewClass(that);
3340 }
3342 @Override
3343 public void visitBinary(JCBinary that) {
3344 if (that.operator == null)
3345 that.operator = new OperatorSymbol(names.empty, syms.unknownType, -1, syms.noSymbol);
3346 super.visitBinary(that);
3347 }
3349 @Override
3350 public void visitUnary(JCUnary that) {
3351 if (that.operator == null)
3352 that.operator = new OperatorSymbol(names.empty, syms.unknownType, -1, syms.noSymbol);
3353 super.visitUnary(that);
3354 }
3355 }
3356 // </editor-fold>
3357 }
