Mon, 24 Jan 2011 15:45:06 +0000
6510286: Wording of javac error for inner classes
Summary: 'inner classes cannot have static declarations' message needs to be reworked
Reviewed-by: jjg
1 /*
2 * Copyright (c) 1999, 2011, Oracle and/or its affiliates. All rights reserved.
3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
4 *
5 * This code is free software; you can redistribute it and/or modify it
6 * under the terms of the GNU General Public License version 2 only, as
7 * published by the Free Software Foundation. Oracle designates this
8 * particular file as subject to the "Classpath" exception as provided
9 * by Oracle in the LICENSE file that accompanied this code.
10 *
11 * This code is distributed in the hope that it will be useful, but WITHOUT
12 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
13 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
14 * version 2 for more details (a copy is included in the LICENSE file that
15 * accompanied this code).
16 *
17 * You should have received a copy of the GNU General Public License version
18 * 2 along with this work; if not, write to the Free Software Foundation,
19 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
20 *
21 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
22 * or visit www.oracle.com if you need additional information or have any
23 * questions.
24 */
26 package com.sun.tools.javac.comp;
28 import java.util.*;
29 import java.util.Set;
30 import javax.lang.model.element.ElementKind;
31 import javax.tools.JavaFileObject;
33 import com.sun.tools.javac.code.*;
34 import com.sun.tools.javac.jvm.*;
35 import com.sun.tools.javac.tree.*;
36 import com.sun.tools.javac.util.*;
37 import com.sun.tools.javac.util.JCDiagnostic.DiagnosticPosition;
38 import com.sun.tools.javac.util.List;
40 import com.sun.tools.javac.jvm.Target;
41 import com.sun.tools.javac.code.Lint.LintCategory;
42 import com.sun.tools.javac.code.Symbol.*;
43 import com.sun.tools.javac.tree.JCTree.*;
44 import com.sun.tools.javac.code.Type.*;
46 import com.sun.source.tree.IdentifierTree;
47 import com.sun.source.tree.MemberSelectTree;
48 import com.sun.source.tree.TreeVisitor;
49 import com.sun.source.util.SimpleTreeVisitor;
51 import static com.sun.tools.javac.code.Flags.*;
52 import static com.sun.tools.javac.code.Kinds.*;
53 import static com.sun.tools.javac.code.TypeTags.*;
55 /** This is the main context-dependent analysis phase in GJC. It
56 * encompasses name resolution, type checking and constant folding as
57 * subtasks. Some subtasks involve auxiliary classes.
58 * @see Check
59 * @see Resolve
60 * @see ConstFold
61 * @see Infer
62 *
63 * <p><b>This is NOT part of any supported API.
64 * If you write code that depends on this, you do so at your own risk.
65 * This code and its internal interfaces are subject to change or
66 * deletion without notice.</b>
67 */
68 public class Attr extends JCTree.Visitor {
69 protected static final Context.Key<Attr> attrKey =
70 new Context.Key<Attr>();
72 final Names names;
73 final Log log;
74 final Symtab syms;
75 final Resolve rs;
76 final Infer infer;
77 final Check chk;
78 final MemberEnter memberEnter;
79 final TreeMaker make;
80 final ConstFold cfolder;
81 final Enter enter;
82 final Target target;
83 final Types types;
84 final JCDiagnostic.Factory diags;
85 final Annotate annotate;
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 /** Attribute type reference in an `extends' or `implements' clause.
585 * Supertypes of anonymous inner classes are usually already attributed.
586 *
587 * @param tree The tree making up the type reference.
588 * @param env The environment current at the reference.
589 * @param classExpected true if only a class is expected here.
590 * @param interfaceExpected true if only an interface is expected here.
591 */
592 Type attribBase(JCTree tree,
593 Env<AttrContext> env,
594 boolean classExpected,
595 boolean interfaceExpected,
596 boolean checkExtensible) {
597 Type t = tree.type != null ?
598 tree.type :
599 attribType(tree, env);
600 return checkBase(t, tree, env, classExpected, interfaceExpected, checkExtensible);
601 }
602 Type checkBase(Type t,
603 JCTree tree,
604 Env<AttrContext> env,
605 boolean classExpected,
606 boolean interfaceExpected,
607 boolean checkExtensible) {
608 if (t.isErroneous())
609 return t;
610 if (t.tag == TYPEVAR && !classExpected && !interfaceExpected) {
611 // check that type variable is already visible
612 if (t.getUpperBound() == null) {
613 log.error(tree.pos(), "illegal.forward.ref");
614 return types.createErrorType(t);
615 }
616 } else {
617 t = chk.checkClassType(tree.pos(), t, checkExtensible|!allowGenerics);
618 }
619 if (interfaceExpected && (t.tsym.flags() & INTERFACE) == 0) {
620 log.error(tree.pos(), "intf.expected.here");
621 // return errType is necessary since otherwise there might
622 // be undetected cycles which cause attribution to loop
623 return types.createErrorType(t);
624 } else if (checkExtensible &&
625 classExpected &&
626 (t.tsym.flags() & INTERFACE) != 0) {
627 log.error(tree.pos(), "no.intf.expected.here");
628 return types.createErrorType(t);
629 }
630 if (checkExtensible &&
631 ((t.tsym.flags() & FINAL) != 0)) {
632 log.error(tree.pos(),
633 "cant.inherit.from.final", t.tsym);
634 }
635 chk.checkNonCyclic(tree.pos(), t);
636 return t;
637 }
639 public void visitClassDef(JCClassDecl tree) {
640 // Local classes have not been entered yet, so we need to do it now:
641 if ((env.info.scope.owner.kind & (VAR | MTH)) != 0)
642 enter.classEnter(tree, env);
644 ClassSymbol c = tree.sym;
645 if (c == null) {
646 // exit in case something drastic went wrong during enter.
647 result = null;
648 } else {
649 // make sure class has been completed:
650 c.complete();
652 // If this class appears as an anonymous class
653 // in a superclass constructor call where
654 // no explicit outer instance is given,
655 // disable implicit outer instance from being passed.
656 // (This would be an illegal access to "this before super").
657 if (env.info.isSelfCall &&
658 env.tree.getTag() == JCTree.NEWCLASS &&
659 ((JCNewClass) env.tree).encl == null)
660 {
661 c.flags_field |= NOOUTERTHIS;
662 }
663 attribClass(tree.pos(), c);
664 result = tree.type = c.type;
665 }
666 }
668 public void visitMethodDef(JCMethodDecl tree) {
669 MethodSymbol m = tree.sym;
671 Lint lint = env.info.lint.augment(m.attributes_field, m.flags());
672 Lint prevLint = chk.setLint(lint);
673 MethodSymbol prevMethod = chk.setMethod(m);
674 try {
675 chk.checkDeprecatedAnnotation(tree.pos(), m);
677 attribBounds(tree.typarams);
679 // If we override any other methods, check that we do so properly.
680 // JLS ???
681 chk.checkClashes(tree.pos(), env.enclClass.type, m);
682 chk.checkOverride(tree, m);
684 // Create a new environment with local scope
685 // for attributing the method.
686 Env<AttrContext> localEnv = memberEnter.methodEnv(tree, env);
688 localEnv.info.lint = lint;
690 // Enter all type parameters into the local method scope.
691 for (List<JCTypeParameter> l = tree.typarams; l.nonEmpty(); l = l.tail)
692 localEnv.info.scope.enterIfAbsent(l.head.type.tsym);
694 ClassSymbol owner = env.enclClass.sym;
695 if ((owner.flags() & ANNOTATION) != 0 &&
696 tree.params.nonEmpty())
697 log.error(tree.params.head.pos(),
698 "intf.annotation.members.cant.have.params");
700 // Attribute all value parameters.
701 for (List<JCVariableDecl> l = tree.params; l.nonEmpty(); l = l.tail) {
702 attribStat(l.head, localEnv);
703 }
705 chk.checkVarargsMethodDecl(localEnv, tree);
707 // Check that type parameters are well-formed.
708 chk.validate(tree.typarams, localEnv);
710 // Check that result type is well-formed.
711 chk.validate(tree.restype, localEnv);
713 // annotation method checks
714 if ((owner.flags() & ANNOTATION) != 0) {
715 // annotation method cannot have throws clause
716 if (tree.thrown.nonEmpty()) {
717 log.error(tree.thrown.head.pos(),
718 "throws.not.allowed.in.intf.annotation");
719 }
720 // annotation method cannot declare type-parameters
721 if (tree.typarams.nonEmpty()) {
722 log.error(tree.typarams.head.pos(),
723 "intf.annotation.members.cant.have.type.params");
724 }
725 // validate annotation method's return type (could be an annotation type)
726 chk.validateAnnotationType(tree.restype);
727 // ensure that annotation method does not clash with members of Object/Annotation
728 chk.validateAnnotationMethod(tree.pos(), m);
730 if (tree.defaultValue != null) {
731 // if default value is an annotation, check it is a well-formed
732 // annotation value (e.g. no duplicate values, no missing values, etc.)
733 chk.validateAnnotationTree(tree.defaultValue);
734 }
735 }
737 for (List<JCExpression> l = tree.thrown; l.nonEmpty(); l = l.tail)
738 chk.checkType(l.head.pos(), l.head.type, syms.throwableType);
740 if (tree.body == null) {
741 // Empty bodies are only allowed for
742 // abstract, native, or interface methods, or for methods
743 // in a retrofit signature class.
744 if ((owner.flags() & INTERFACE) == 0 &&
745 (tree.mods.flags & (ABSTRACT | NATIVE)) == 0 &&
746 !relax)
747 log.error(tree.pos(), "missing.meth.body.or.decl.abstract");
748 if (tree.defaultValue != null) {
749 if ((owner.flags() & ANNOTATION) == 0)
750 log.error(tree.pos(),
751 "default.allowed.in.intf.annotation.member");
752 }
753 } else if ((owner.flags() & INTERFACE) != 0) {
754 log.error(tree.body.pos(), "intf.meth.cant.have.body");
755 } else if ((tree.mods.flags & ABSTRACT) != 0) {
756 log.error(tree.pos(), "abstract.meth.cant.have.body");
757 } else if ((tree.mods.flags & NATIVE) != 0) {
758 log.error(tree.pos(), "native.meth.cant.have.body");
759 } else {
760 // Add an implicit super() call unless an explicit call to
761 // super(...) or this(...) is given
762 // or we are compiling class java.lang.Object.
763 if (tree.name == names.init && owner.type != syms.objectType) {
764 JCBlock body = tree.body;
765 if (body.stats.isEmpty() ||
766 !TreeInfo.isSelfCall(body.stats.head)) {
767 body.stats = body.stats.
768 prepend(memberEnter.SuperCall(make.at(body.pos),
769 List.<Type>nil(),
770 List.<JCVariableDecl>nil(),
771 false));
772 } else if ((env.enclClass.sym.flags() & ENUM) != 0 &&
773 (tree.mods.flags & GENERATEDCONSTR) == 0 &&
774 TreeInfo.isSuperCall(body.stats.head)) {
775 // enum constructors are not allowed to call super
776 // directly, so make sure there aren't any super calls
777 // in enum constructors, except in the compiler
778 // generated one.
779 log.error(tree.body.stats.head.pos(),
780 "call.to.super.not.allowed.in.enum.ctor",
781 env.enclClass.sym);
782 }
783 }
785 // Attribute method body.
786 attribStat(tree.body, localEnv);
787 }
788 localEnv.info.scope.leave();
789 result = tree.type = m.type;
790 chk.validateAnnotations(tree.mods.annotations, m);
791 }
792 finally {
793 chk.setLint(prevLint);
794 chk.setMethod(prevMethod);
795 }
796 }
798 public void visitVarDef(JCVariableDecl tree) {
799 // Local variables have not been entered yet, so we need to do it now:
800 if (env.info.scope.owner.kind == MTH) {
801 if (tree.sym != null) {
802 // parameters have already been entered
803 env.info.scope.enter(tree.sym);
804 } else {
805 memberEnter.memberEnter(tree, env);
806 annotate.flush();
807 }
808 tree.sym.flags_field |= EFFECTIVELY_FINAL;
809 }
811 VarSymbol v = tree.sym;
812 Lint lint = env.info.lint.augment(v.attributes_field, v.flags());
813 Lint prevLint = chk.setLint(lint);
815 // Check that the variable's declared type is well-formed.
816 chk.validate(tree.vartype, env);
818 try {
819 chk.checkDeprecatedAnnotation(tree.pos(), v);
821 if (tree.init != null) {
822 if ((v.flags_field & FINAL) != 0 && tree.init.getTag() != JCTree.NEWCLASS) {
823 // In this case, `v' is final. Ensure that it's initializer is
824 // evaluated.
825 v.getConstValue(); // ensure initializer is evaluated
826 } else {
827 // Attribute initializer in a new environment
828 // with the declared variable as owner.
829 // Check that initializer conforms to variable's declared type.
830 Env<AttrContext> initEnv = memberEnter.initEnv(tree, env);
831 initEnv.info.lint = lint;
832 // In order to catch self-references, we set the variable's
833 // declaration position to maximal possible value, effectively
834 // marking the variable as undefined.
835 initEnv.info.enclVar = v;
836 attribExpr(tree.init, initEnv, v.type);
837 }
838 }
839 result = tree.type = v.type;
840 chk.validateAnnotations(tree.mods.annotations, v);
841 }
842 finally {
843 chk.setLint(prevLint);
844 }
845 }
847 public void visitSkip(JCSkip tree) {
848 result = null;
849 }
851 public void visitBlock(JCBlock tree) {
852 if (env.info.scope.owner.kind == TYP) {
853 // Block is a static or instance initializer;
854 // let the owner of the environment be a freshly
855 // created BLOCK-method.
856 Env<AttrContext> localEnv =
857 env.dup(tree, env.info.dup(env.info.scope.dupUnshared()));
858 localEnv.info.scope.owner =
859 new MethodSymbol(tree.flags | BLOCK, names.empty, null,
860 env.info.scope.owner);
861 if ((tree.flags & STATIC) != 0) localEnv.info.staticLevel++;
862 attribStats(tree.stats, localEnv);
863 } else {
864 // Create a new local environment with a local scope.
865 Env<AttrContext> localEnv =
866 env.dup(tree, env.info.dup(env.info.scope.dup()));
867 attribStats(tree.stats, localEnv);
868 localEnv.info.scope.leave();
869 }
870 result = null;
871 }
873 public void visitDoLoop(JCDoWhileLoop tree) {
874 attribStat(tree.body, env.dup(tree));
875 attribExpr(tree.cond, env, syms.booleanType);
876 result = null;
877 }
879 public void visitWhileLoop(JCWhileLoop tree) {
880 attribExpr(tree.cond, env, syms.booleanType);
881 attribStat(tree.body, env.dup(tree));
882 result = null;
883 }
885 public void visitForLoop(JCForLoop tree) {
886 Env<AttrContext> loopEnv =
887 env.dup(env.tree, env.info.dup(env.info.scope.dup()));
888 attribStats(tree.init, loopEnv);
889 if (tree.cond != null) attribExpr(tree.cond, loopEnv, syms.booleanType);
890 loopEnv.tree = tree; // before, we were not in loop!
891 attribStats(tree.step, loopEnv);
892 attribStat(tree.body, loopEnv);
893 loopEnv.info.scope.leave();
894 result = null;
895 }
897 public void visitForeachLoop(JCEnhancedForLoop tree) {
898 Env<AttrContext> loopEnv =
899 env.dup(env.tree, env.info.dup(env.info.scope.dup()));
900 attribStat(tree.var, loopEnv);
901 Type exprType = types.upperBound(attribExpr(tree.expr, loopEnv));
902 chk.checkNonVoid(tree.pos(), exprType);
903 Type elemtype = types.elemtype(exprType); // perhaps expr is an array?
904 if (elemtype == null) {
905 // or perhaps expr implements Iterable<T>?
906 Type base = types.asSuper(exprType, syms.iterableType.tsym);
907 if (base == null) {
908 log.error(tree.expr.pos(),
909 "foreach.not.applicable.to.type",
910 exprType,
911 diags.fragment("type.req.array.or.iterable"));
912 elemtype = types.createErrorType(exprType);
913 } else {
914 List<Type> iterableParams = base.allparams();
915 elemtype = iterableParams.isEmpty()
916 ? syms.objectType
917 : types.upperBound(iterableParams.head);
918 }
919 }
920 chk.checkType(tree.expr.pos(), elemtype, tree.var.sym.type);
921 loopEnv.tree = tree; // before, we were not in loop!
922 attribStat(tree.body, loopEnv);
923 loopEnv.info.scope.leave();
924 result = null;
925 }
927 public void visitLabelled(JCLabeledStatement tree) {
928 // Check that label is not used in an enclosing statement
929 Env<AttrContext> env1 = env;
930 while (env1 != null && env1.tree.getTag() != JCTree.CLASSDEF) {
931 if (env1.tree.getTag() == JCTree.LABELLED &&
932 ((JCLabeledStatement) env1.tree).label == tree.label) {
933 log.error(tree.pos(), "label.already.in.use",
934 tree.label);
935 break;
936 }
937 env1 = env1.next;
938 }
940 attribStat(tree.body, env.dup(tree));
941 result = null;
942 }
944 public void visitSwitch(JCSwitch tree) {
945 Type seltype = attribExpr(tree.selector, env);
947 Env<AttrContext> switchEnv =
948 env.dup(tree, env.info.dup(env.info.scope.dup()));
950 boolean enumSwitch =
951 allowEnums &&
952 (seltype.tsym.flags() & Flags.ENUM) != 0;
953 boolean stringSwitch = false;
954 if (types.isSameType(seltype, syms.stringType)) {
955 if (allowStringsInSwitch) {
956 stringSwitch = true;
957 } else {
958 log.error(tree.selector.pos(), "string.switch.not.supported.in.source", sourceName);
959 }
960 }
961 if (!enumSwitch && !stringSwitch)
962 seltype = chk.checkType(tree.selector.pos(), seltype, syms.intType);
964 // Attribute all cases and
965 // check that there are no duplicate case labels or default clauses.
966 Set<Object> labels = new HashSet<Object>(); // The set of case labels.
967 boolean hasDefault = false; // Is there a default label?
968 for (List<JCCase> l = tree.cases; l.nonEmpty(); l = l.tail) {
969 JCCase c = l.head;
970 Env<AttrContext> caseEnv =
971 switchEnv.dup(c, env.info.dup(switchEnv.info.scope.dup()));
972 if (c.pat != null) {
973 if (enumSwitch) {
974 Symbol sym = enumConstant(c.pat, seltype);
975 if (sym == null) {
976 log.error(c.pat.pos(), "enum.label.must.be.unqualified.enum");
977 } else if (!labels.add(sym)) {
978 log.error(c.pos(), "duplicate.case.label");
979 }
980 } else {
981 Type pattype = attribExpr(c.pat, switchEnv, seltype);
982 if (pattype.tag != ERROR) {
983 if (pattype.constValue() == null) {
984 log.error(c.pat.pos(),
985 (stringSwitch ? "string.const.req" : "const.expr.req"));
986 } else if (labels.contains(pattype.constValue())) {
987 log.error(c.pos(), "duplicate.case.label");
988 } else {
989 labels.add(pattype.constValue());
990 }
991 }
992 }
993 } else if (hasDefault) {
994 log.error(c.pos(), "duplicate.default.label");
995 } else {
996 hasDefault = true;
997 }
998 attribStats(c.stats, caseEnv);
999 caseEnv.info.scope.leave();
1000 addVars(c.stats, switchEnv.info.scope);
1001 }
1003 switchEnv.info.scope.leave();
1004 result = null;
1005 }
1006 // where
1007 /** Add any variables defined in stats to the switch scope. */
1008 private static void addVars(List<JCStatement> stats, Scope switchScope) {
1009 for (;stats.nonEmpty(); stats = stats.tail) {
1010 JCTree stat = stats.head;
1011 if (stat.getTag() == JCTree.VARDEF)
1012 switchScope.enter(((JCVariableDecl) stat).sym);
1013 }
1014 }
1015 // where
1016 /** Return the selected enumeration constant symbol, or null. */
1017 private Symbol enumConstant(JCTree tree, Type enumType) {
1018 if (tree.getTag() != JCTree.IDENT) {
1019 log.error(tree.pos(), "enum.label.must.be.unqualified.enum");
1020 return syms.errSymbol;
1021 }
1022 JCIdent ident = (JCIdent)tree;
1023 Name name = ident.name;
1024 for (Scope.Entry e = enumType.tsym.members().lookup(name);
1025 e.scope != null; e = e.next()) {
1026 if (e.sym.kind == VAR) {
1027 Symbol s = ident.sym = e.sym;
1028 ((VarSymbol)s).getConstValue(); // ensure initializer is evaluated
1029 ident.type = s.type;
1030 return ((s.flags_field & Flags.ENUM) == 0)
1031 ? null : s;
1032 }
1033 }
1034 return null;
1035 }
1037 public void visitSynchronized(JCSynchronized tree) {
1038 chk.checkRefType(tree.pos(), attribExpr(tree.lock, env));
1039 attribStat(tree.body, env);
1040 result = null;
1041 }
1043 public void visitTry(JCTry tree) {
1044 // Create a new local environment with a local
1045 Env<AttrContext> localEnv = env.dup(tree, env.info.dup(env.info.scope.dup()));
1046 boolean isTryWithResource = tree.resources.nonEmpty();
1047 // Create a nested environment for attributing the try block if needed
1048 Env<AttrContext> tryEnv = isTryWithResource ?
1049 env.dup(tree, localEnv.info.dup(localEnv.info.scope.dup())) :
1050 localEnv;
1051 // Attribute resource declarations
1052 for (JCTree resource : tree.resources) {
1053 if (resource.getTag() == JCTree.VARDEF) {
1054 attribStat(resource, tryEnv);
1055 chk.checkType(resource, resource.type, syms.autoCloseableType, "try.not.applicable.to.type");
1056 VarSymbol var = (VarSymbol)TreeInfo.symbolFor(resource);
1057 var.setData(ElementKind.RESOURCE_VARIABLE);
1058 } else {
1059 attribExpr(resource, tryEnv, syms.autoCloseableType, "try.not.applicable.to.type");
1060 }
1061 }
1062 // Attribute body
1063 attribStat(tree.body, tryEnv);
1064 if (isTryWithResource)
1065 tryEnv.info.scope.leave();
1067 // Attribute catch clauses
1068 for (List<JCCatch> l = tree.catchers; l.nonEmpty(); l = l.tail) {
1069 JCCatch c = l.head;
1070 Env<AttrContext> catchEnv =
1071 localEnv.dup(c, localEnv.info.dup(localEnv.info.scope.dup()));
1072 Type ctype = attribStat(c.param, catchEnv);
1073 if (TreeInfo.isMultiCatch(c)) {
1074 //multi-catch parameter is implicitly marked as final
1075 c.param.sym.flags_field |= FINAL | DISJUNCTION;
1076 }
1077 if (c.param.sym.kind == Kinds.VAR) {
1078 c.param.sym.setData(ElementKind.EXCEPTION_PARAMETER);
1079 }
1080 chk.checkType(c.param.vartype.pos(),
1081 chk.checkClassType(c.param.vartype.pos(), ctype),
1082 syms.throwableType);
1083 attribStat(c.body, catchEnv);
1084 catchEnv.info.scope.leave();
1085 }
1087 // Attribute finalizer
1088 if (tree.finalizer != null) attribStat(tree.finalizer, localEnv);
1090 localEnv.info.scope.leave();
1091 result = null;
1092 }
1094 public void visitConditional(JCConditional tree) {
1095 attribExpr(tree.cond, env, syms.booleanType);
1096 attribExpr(tree.truepart, env);
1097 attribExpr(tree.falsepart, env);
1098 result = check(tree,
1099 capture(condType(tree.pos(), tree.cond.type,
1100 tree.truepart.type, tree.falsepart.type)),
1101 VAL, pkind, pt);
1102 }
1103 //where
1104 /** Compute the type of a conditional expression, after
1105 * checking that it exists. See Spec 15.25.
1106 *
1107 * @param pos The source position to be used for
1108 * error diagnostics.
1109 * @param condtype The type of the expression's condition.
1110 * @param thentype The type of the expression's then-part.
1111 * @param elsetype The type of the expression's else-part.
1112 */
1113 private Type condType(DiagnosticPosition pos,
1114 Type condtype,
1115 Type thentype,
1116 Type elsetype) {
1117 Type ctype = condType1(pos, condtype, thentype, elsetype);
1119 // If condition and both arms are numeric constants,
1120 // evaluate at compile-time.
1121 return ((condtype.constValue() != null) &&
1122 (thentype.constValue() != null) &&
1123 (elsetype.constValue() != null))
1124 ? cfolder.coerce(condtype.isTrue()?thentype:elsetype, ctype)
1125 : ctype;
1126 }
1127 /** Compute the type of a conditional expression, after
1128 * checking that it exists. Does not take into
1129 * account the special case where condition and both arms
1130 * are constants.
1131 *
1132 * @param pos The source position to be used for error
1133 * diagnostics.
1134 * @param condtype The type of the expression's condition.
1135 * @param thentype The type of the expression's then-part.
1136 * @param elsetype The type of the expression's else-part.
1137 */
1138 private Type condType1(DiagnosticPosition pos, Type condtype,
1139 Type thentype, Type elsetype) {
1140 // If same type, that is the result
1141 if (types.isSameType(thentype, elsetype))
1142 return thentype.baseType();
1144 Type thenUnboxed = (!allowBoxing || thentype.isPrimitive())
1145 ? thentype : types.unboxedType(thentype);
1146 Type elseUnboxed = (!allowBoxing || elsetype.isPrimitive())
1147 ? elsetype : types.unboxedType(elsetype);
1149 // Otherwise, if both arms can be converted to a numeric
1150 // type, return the least numeric type that fits both arms
1151 // (i.e. return larger of the two, or return int if one
1152 // arm is short, the other is char).
1153 if (thenUnboxed.isPrimitive() && elseUnboxed.isPrimitive()) {
1154 // If one arm has an integer subrange type (i.e., byte,
1155 // short, or char), and the other is an integer constant
1156 // that fits into the subrange, return the subrange type.
1157 if (thenUnboxed.tag < INT && elseUnboxed.tag == INT &&
1158 types.isAssignable(elseUnboxed, thenUnboxed))
1159 return thenUnboxed.baseType();
1160 if (elseUnboxed.tag < INT && thenUnboxed.tag == INT &&
1161 types.isAssignable(thenUnboxed, elseUnboxed))
1162 return elseUnboxed.baseType();
1164 for (int i = BYTE; i < VOID; i++) {
1165 Type candidate = syms.typeOfTag[i];
1166 if (types.isSubtype(thenUnboxed, candidate) &&
1167 types.isSubtype(elseUnboxed, candidate))
1168 return candidate;
1169 }
1170 }
1172 // Those were all the cases that could result in a primitive
1173 if (allowBoxing) {
1174 if (thentype.isPrimitive())
1175 thentype = types.boxedClass(thentype).type;
1176 if (elsetype.isPrimitive())
1177 elsetype = types.boxedClass(elsetype).type;
1178 }
1180 if (types.isSubtype(thentype, elsetype))
1181 return elsetype.baseType();
1182 if (types.isSubtype(elsetype, thentype))
1183 return thentype.baseType();
1185 if (!allowBoxing || thentype.tag == VOID || elsetype.tag == VOID) {
1186 log.error(pos, "neither.conditional.subtype",
1187 thentype, elsetype);
1188 return thentype.baseType();
1189 }
1191 // both are known to be reference types. The result is
1192 // lub(thentype,elsetype). This cannot fail, as it will
1193 // always be possible to infer "Object" if nothing better.
1194 return types.lub(thentype.baseType(), elsetype.baseType());
1195 }
1197 public void visitIf(JCIf tree) {
1198 attribExpr(tree.cond, env, syms.booleanType);
1199 attribStat(tree.thenpart, env);
1200 if (tree.elsepart != null)
1201 attribStat(tree.elsepart, env);
1202 chk.checkEmptyIf(tree);
1203 result = null;
1204 }
1206 public void visitExec(JCExpressionStatement tree) {
1207 //a fresh environment is required for 292 inference to work properly ---
1208 //see Infer.instantiatePolymorphicSignatureInstance()
1209 Env<AttrContext> localEnv = env.dup(tree);
1210 attribExpr(tree.expr, localEnv);
1211 result = null;
1212 }
1214 public void visitBreak(JCBreak tree) {
1215 tree.target = findJumpTarget(tree.pos(), tree.getTag(), tree.label, env);
1216 result = null;
1217 }
1219 public void visitContinue(JCContinue tree) {
1220 tree.target = findJumpTarget(tree.pos(), tree.getTag(), tree.label, env);
1221 result = null;
1222 }
1223 //where
1224 /** Return the target of a break or continue statement, if it exists,
1225 * report an error if not.
1226 * Note: The target of a labelled break or continue is the
1227 * (non-labelled) statement tree referred to by the label,
1228 * not the tree representing the labelled statement itself.
1229 *
1230 * @param pos The position to be used for error diagnostics
1231 * @param tag The tag of the jump statement. This is either
1232 * Tree.BREAK or Tree.CONTINUE.
1233 * @param label The label of the jump statement, or null if no
1234 * label is given.
1235 * @param env The environment current at the jump statement.
1236 */
1237 private JCTree findJumpTarget(DiagnosticPosition pos,
1238 int tag,
1239 Name label,
1240 Env<AttrContext> env) {
1241 // Search environments outwards from the point of jump.
1242 Env<AttrContext> env1 = env;
1243 LOOP:
1244 while (env1 != null) {
1245 switch (env1.tree.getTag()) {
1246 case JCTree.LABELLED:
1247 JCLabeledStatement labelled = (JCLabeledStatement)env1.tree;
1248 if (label == labelled.label) {
1249 // If jump is a continue, check that target is a loop.
1250 if (tag == JCTree.CONTINUE) {
1251 if (labelled.body.getTag() != JCTree.DOLOOP &&
1252 labelled.body.getTag() != JCTree.WHILELOOP &&
1253 labelled.body.getTag() != JCTree.FORLOOP &&
1254 labelled.body.getTag() != JCTree.FOREACHLOOP)
1255 log.error(pos, "not.loop.label", label);
1256 // Found labelled statement target, now go inwards
1257 // to next non-labelled tree.
1258 return TreeInfo.referencedStatement(labelled);
1259 } else {
1260 return labelled;
1261 }
1262 }
1263 break;
1264 case JCTree.DOLOOP:
1265 case JCTree.WHILELOOP:
1266 case JCTree.FORLOOP:
1267 case JCTree.FOREACHLOOP:
1268 if (label == null) return env1.tree;
1269 break;
1270 case JCTree.SWITCH:
1271 if (label == null && tag == JCTree.BREAK) return env1.tree;
1272 break;
1273 case JCTree.METHODDEF:
1274 case JCTree.CLASSDEF:
1275 break LOOP;
1276 default:
1277 }
1278 env1 = env1.next;
1279 }
1280 if (label != null)
1281 log.error(pos, "undef.label", label);
1282 else if (tag == JCTree.CONTINUE)
1283 log.error(pos, "cont.outside.loop");
1284 else
1285 log.error(pos, "break.outside.switch.loop");
1286 return null;
1287 }
1289 public void visitReturn(JCReturn tree) {
1290 // Check that there is an enclosing method which is
1291 // nested within than the enclosing class.
1292 if (env.enclMethod == null ||
1293 env.enclMethod.sym.owner != env.enclClass.sym) {
1294 log.error(tree.pos(), "ret.outside.meth");
1296 } else {
1297 // Attribute return expression, if it exists, and check that
1298 // it conforms to result type of enclosing method.
1299 Symbol m = env.enclMethod.sym;
1300 if (m.type.getReturnType().tag == VOID) {
1301 if (tree.expr != null)
1302 log.error(tree.expr.pos(),
1303 "cant.ret.val.from.meth.decl.void");
1304 } else if (tree.expr == null) {
1305 log.error(tree.pos(), "missing.ret.val");
1306 } else {
1307 attribExpr(tree.expr, env, m.type.getReturnType());
1308 }
1309 }
1310 result = null;
1311 }
1313 public void visitThrow(JCThrow tree) {
1314 attribExpr(tree.expr, env, syms.throwableType);
1315 result = null;
1316 }
1318 public void visitAssert(JCAssert tree) {
1319 attribExpr(tree.cond, env, syms.booleanType);
1320 if (tree.detail != null) {
1321 chk.checkNonVoid(tree.detail.pos(), attribExpr(tree.detail, env));
1322 }
1323 result = null;
1324 }
1326 /** Visitor method for method invocations.
1327 * NOTE: The method part of an application will have in its type field
1328 * the return type of the method, not the method's type itself!
1329 */
1330 public void visitApply(JCMethodInvocation tree) {
1331 // The local environment of a method application is
1332 // a new environment nested in the current one.
1333 Env<AttrContext> localEnv = env.dup(tree, env.info.dup());
1335 // The types of the actual method arguments.
1336 List<Type> argtypes;
1338 // The types of the actual method type arguments.
1339 List<Type> typeargtypes = null;
1341 Name methName = TreeInfo.name(tree.meth);
1343 boolean isConstructorCall =
1344 methName == names._this || methName == names._super;
1346 if (isConstructorCall) {
1347 // We are seeing a ...this(...) or ...super(...) call.
1348 // Check that this is the first statement in a constructor.
1349 if (checkFirstConstructorStat(tree, env)) {
1351 // Record the fact
1352 // that this is a constructor call (using isSelfCall).
1353 localEnv.info.isSelfCall = true;
1355 // Attribute arguments, yielding list of argument types.
1356 argtypes = attribArgs(tree.args, localEnv);
1357 typeargtypes = attribTypes(tree.typeargs, localEnv);
1359 // Variable `site' points to the class in which the called
1360 // constructor is defined.
1361 Type site = env.enclClass.sym.type;
1362 if (methName == names._super) {
1363 if (site == syms.objectType) {
1364 log.error(tree.meth.pos(), "no.superclass", site);
1365 site = types.createErrorType(syms.objectType);
1366 } else {
1367 site = types.supertype(site);
1368 }
1369 }
1371 if (site.tag == CLASS) {
1372 Type encl = site.getEnclosingType();
1373 while (encl != null && encl.tag == TYPEVAR)
1374 encl = encl.getUpperBound();
1375 if (encl.tag == CLASS) {
1376 // we are calling a nested class
1378 if (tree.meth.getTag() == JCTree.SELECT) {
1379 JCTree qualifier = ((JCFieldAccess) tree.meth).selected;
1381 // We are seeing a prefixed call, of the form
1382 // <expr>.super(...).
1383 // Check that the prefix expression conforms
1384 // to the outer instance type of the class.
1385 chk.checkRefType(qualifier.pos(),
1386 attribExpr(qualifier, localEnv,
1387 encl));
1388 } else if (methName == names._super) {
1389 // qualifier omitted; check for existence
1390 // of an appropriate implicit qualifier.
1391 rs.resolveImplicitThis(tree.meth.pos(),
1392 localEnv, site);
1393 }
1394 } else if (tree.meth.getTag() == JCTree.SELECT) {
1395 log.error(tree.meth.pos(), "illegal.qual.not.icls",
1396 site.tsym);
1397 }
1399 // if we're calling a java.lang.Enum constructor,
1400 // prefix the implicit String and int parameters
1401 if (site.tsym == syms.enumSym && allowEnums)
1402 argtypes = argtypes.prepend(syms.intType).prepend(syms.stringType);
1404 // Resolve the called constructor under the assumption
1405 // that we are referring to a superclass instance of the
1406 // current instance (JLS ???).
1407 boolean selectSuperPrev = localEnv.info.selectSuper;
1408 localEnv.info.selectSuper = true;
1409 localEnv.info.varArgs = false;
1410 Symbol sym = rs.resolveConstructor(
1411 tree.meth.pos(), localEnv, site, argtypes, typeargtypes);
1412 localEnv.info.selectSuper = selectSuperPrev;
1414 // Set method symbol to resolved constructor...
1415 TreeInfo.setSymbol(tree.meth, sym);
1417 // ...and check that it is legal in the current context.
1418 // (this will also set the tree's type)
1419 Type mpt = newMethTemplate(argtypes, typeargtypes);
1420 checkId(tree.meth, site, sym, localEnv, MTH,
1421 mpt, tree.varargsElement != null);
1422 }
1423 // Otherwise, `site' is an error type and we do nothing
1424 }
1425 result = tree.type = syms.voidType;
1426 } else {
1427 // Otherwise, we are seeing a regular method call.
1428 // Attribute the arguments, yielding list of argument types, ...
1429 argtypes = attribArgs(tree.args, localEnv);
1430 typeargtypes = attribAnyTypes(tree.typeargs, localEnv);
1432 // ... and attribute the method using as a prototype a methodtype
1433 // whose formal argument types is exactly the list of actual
1434 // arguments (this will also set the method symbol).
1435 Type mpt = newMethTemplate(argtypes, typeargtypes);
1436 localEnv.info.varArgs = false;
1437 Type mtype = attribExpr(tree.meth, localEnv, mpt);
1438 if (localEnv.info.varArgs)
1439 Assert.check(mtype.isErroneous() || tree.varargsElement != null);
1441 // Compute the result type.
1442 Type restype = mtype.getReturnType();
1443 if (restype.tag == WILDCARD)
1444 throw new AssertionError(mtype);
1446 // as a special case, array.clone() has a result that is
1447 // the same as static type of the array being cloned
1448 if (tree.meth.getTag() == JCTree.SELECT &&
1449 allowCovariantReturns &&
1450 methName == names.clone &&
1451 types.isArray(((JCFieldAccess) tree.meth).selected.type))
1452 restype = ((JCFieldAccess) tree.meth).selected.type;
1454 // as a special case, x.getClass() has type Class<? extends |X|>
1455 if (allowGenerics &&
1456 methName == names.getClass && tree.args.isEmpty()) {
1457 Type qualifier = (tree.meth.getTag() == JCTree.SELECT)
1458 ? ((JCFieldAccess) tree.meth).selected.type
1459 : env.enclClass.sym.type;
1460 restype = new
1461 ClassType(restype.getEnclosingType(),
1462 List.<Type>of(new WildcardType(types.erasure(qualifier),
1463 BoundKind.EXTENDS,
1464 syms.boundClass)),
1465 restype.tsym);
1466 }
1468 chk.checkRefTypes(tree.typeargs, typeargtypes);
1470 // Check that value of resulting type is admissible in the
1471 // current context. Also, capture the return type
1472 result = check(tree, capture(restype), VAL, pkind, pt);
1473 }
1474 chk.validate(tree.typeargs, localEnv);
1475 }
1476 //where
1477 /** Check that given application node appears as first statement
1478 * in a constructor call.
1479 * @param tree The application node
1480 * @param env The environment current at the application.
1481 */
1482 boolean checkFirstConstructorStat(JCMethodInvocation tree, Env<AttrContext> env) {
1483 JCMethodDecl enclMethod = env.enclMethod;
1484 if (enclMethod != null && enclMethod.name == names.init) {
1485 JCBlock body = enclMethod.body;
1486 if (body.stats.head.getTag() == JCTree.EXEC &&
1487 ((JCExpressionStatement) body.stats.head).expr == tree)
1488 return true;
1489 }
1490 log.error(tree.pos(),"call.must.be.first.stmt.in.ctor",
1491 TreeInfo.name(tree.meth));
1492 return false;
1493 }
1495 /** Obtain a method type with given argument types.
1496 */
1497 Type newMethTemplate(List<Type> argtypes, List<Type> typeargtypes) {
1498 MethodType mt = new MethodType(argtypes, null, null, syms.methodClass);
1499 return (typeargtypes == null) ? mt : (Type)new ForAll(typeargtypes, mt);
1500 }
1502 public void visitNewClass(JCNewClass tree) {
1503 Type owntype = types.createErrorType(tree.type);
1505 // The local environment of a class creation is
1506 // a new environment nested in the current one.
1507 Env<AttrContext> localEnv = env.dup(tree, env.info.dup());
1509 // The anonymous inner class definition of the new expression,
1510 // if one is defined by it.
1511 JCClassDecl cdef = tree.def;
1513 // If enclosing class is given, attribute it, and
1514 // complete class name to be fully qualified
1515 JCExpression clazz = tree.clazz; // Class field following new
1516 JCExpression clazzid = // Identifier in class field
1517 (clazz.getTag() == JCTree.TYPEAPPLY)
1518 ? ((JCTypeApply) clazz).clazz
1519 : clazz;
1521 JCExpression clazzid1 = clazzid; // The same in fully qualified form
1523 if (tree.encl != null) {
1524 // We are seeing a qualified new, of the form
1525 // <expr>.new C <...> (...) ...
1526 // In this case, we let clazz stand for the name of the
1527 // allocated class C prefixed with the type of the qualifier
1528 // expression, so that we can
1529 // resolve it with standard techniques later. I.e., if
1530 // <expr> has type T, then <expr>.new C <...> (...)
1531 // yields a clazz T.C.
1532 Type encltype = chk.checkRefType(tree.encl.pos(),
1533 attribExpr(tree.encl, env));
1534 clazzid1 = make.at(clazz.pos).Select(make.Type(encltype),
1535 ((JCIdent) clazzid).name);
1536 if (clazz.getTag() == JCTree.TYPEAPPLY)
1537 clazz = make.at(tree.pos).
1538 TypeApply(clazzid1,
1539 ((JCTypeApply) clazz).arguments);
1540 else
1541 clazz = clazzid1;
1542 }
1544 // Attribute clazz expression and store
1545 // symbol + type back into the attributed tree.
1546 Type clazztype = attribType(clazz, env);
1547 Pair<Scope,Scope> mapping = getSyntheticScopeMapping(clazztype, cdef != null);
1548 if (!TreeInfo.isDiamond(tree)) {
1549 clazztype = chk.checkClassType(
1550 tree.clazz.pos(), clazztype, true);
1551 }
1552 chk.validate(clazz, localEnv);
1553 if (tree.encl != null) {
1554 // We have to work in this case to store
1555 // symbol + type back into the attributed tree.
1556 tree.clazz.type = clazztype;
1557 TreeInfo.setSymbol(clazzid, TreeInfo.symbol(clazzid1));
1558 clazzid.type = ((JCIdent) clazzid).sym.type;
1559 if (!clazztype.isErroneous()) {
1560 if (cdef != null && clazztype.tsym.isInterface()) {
1561 log.error(tree.encl.pos(), "anon.class.impl.intf.no.qual.for.new");
1562 } else if (clazztype.tsym.isStatic()) {
1563 log.error(tree.encl.pos(), "qualified.new.of.static.class", clazztype.tsym);
1564 }
1565 }
1566 } else if (!clazztype.tsym.isInterface() &&
1567 clazztype.getEnclosingType().tag == CLASS) {
1568 // Check for the existence of an apropos outer instance
1569 rs.resolveImplicitThis(tree.pos(), env, clazztype);
1570 }
1572 // Attribute constructor arguments.
1573 List<Type> argtypes = attribArgs(tree.args, localEnv);
1574 List<Type> typeargtypes = attribTypes(tree.typeargs, localEnv);
1576 if (TreeInfo.isDiamond(tree)) {
1577 clazztype = attribDiamond(localEnv, tree, clazztype, mapping, argtypes, typeargtypes);
1578 clazz.type = clazztype;
1579 } else if (allowDiamondFinder &&
1580 clazztype.getTypeArguments().nonEmpty() &&
1581 findDiamonds) {
1582 boolean prevDeferDiags = log.deferDiagnostics;
1583 Queue<JCDiagnostic> prevDeferredDiags = log.deferredDiagnostics;
1584 Type inferred = null;
1585 try {
1586 //disable diamond-related diagnostics
1587 log.deferDiagnostics = true;
1588 log.deferredDiagnostics = ListBuffer.lb();
1589 inferred = attribDiamond(localEnv,
1590 tree,
1591 clazztype,
1592 mapping,
1593 argtypes,
1594 typeargtypes);
1595 }
1596 finally {
1597 log.deferDiagnostics = prevDeferDiags;
1598 log.deferredDiagnostics = prevDeferredDiags;
1599 }
1600 if (inferred != null &&
1601 !inferred.isErroneous() &&
1602 inferred.tag == CLASS &&
1603 types.isAssignable(inferred, pt.tag == NONE ? clazztype : pt, Warner.noWarnings) &&
1604 chk.checkDiamond((ClassType)inferred).isEmpty()) {
1605 String key = types.isSameType(clazztype, inferred) ?
1606 "diamond.redundant.args" :
1607 "diamond.redundant.args.1";
1608 log.warning(tree.clazz.pos(), key, clazztype, inferred);
1609 }
1610 }
1612 // If we have made no mistakes in the class type...
1613 if (clazztype.tag == CLASS) {
1614 // Enums may not be instantiated except implicitly
1615 if (allowEnums &&
1616 (clazztype.tsym.flags_field&Flags.ENUM) != 0 &&
1617 (env.tree.getTag() != JCTree.VARDEF ||
1618 (((JCVariableDecl) env.tree).mods.flags&Flags.ENUM) == 0 ||
1619 ((JCVariableDecl) env.tree).init != tree))
1620 log.error(tree.pos(), "enum.cant.be.instantiated");
1621 // Check that class is not abstract
1622 if (cdef == null &&
1623 (clazztype.tsym.flags() & (ABSTRACT | INTERFACE)) != 0) {
1624 log.error(tree.pos(), "abstract.cant.be.instantiated",
1625 clazztype.tsym);
1626 } else if (cdef != null && clazztype.tsym.isInterface()) {
1627 // Check that no constructor arguments are given to
1628 // anonymous classes implementing an interface
1629 if (!argtypes.isEmpty())
1630 log.error(tree.args.head.pos(), "anon.class.impl.intf.no.args");
1632 if (!typeargtypes.isEmpty())
1633 log.error(tree.typeargs.head.pos(), "anon.class.impl.intf.no.typeargs");
1635 // Error recovery: pretend no arguments were supplied.
1636 argtypes = List.nil();
1637 typeargtypes = List.nil();
1638 }
1640 // Resolve the called constructor under the assumption
1641 // that we are referring to a superclass instance of the
1642 // current instance (JLS ???).
1643 else {
1644 localEnv.info.selectSuper = cdef != null;
1645 localEnv.info.varArgs = false;
1646 tree.constructor = rs.resolveConstructor(
1647 tree.pos(), localEnv, clazztype, argtypes, typeargtypes);
1648 tree.constructorType = tree.constructor.type.isErroneous() ?
1649 syms.errType :
1650 checkMethod(clazztype,
1651 tree.constructor,
1652 localEnv,
1653 tree.args,
1654 argtypes,
1655 typeargtypes,
1656 localEnv.info.varArgs);
1657 if (localEnv.info.varArgs)
1658 Assert.check(tree.constructorType.isErroneous() || tree.varargsElement != null);
1659 }
1661 if (cdef != null) {
1662 // We are seeing an anonymous class instance creation.
1663 // In this case, the class instance creation
1664 // expression
1665 //
1666 // E.new <typeargs1>C<typargs2>(args) { ... }
1667 //
1668 // is represented internally as
1669 //
1670 // E . new <typeargs1>C<typargs2>(args) ( class <empty-name> { ... } ) .
1671 //
1672 // This expression is then *transformed* as follows:
1673 //
1674 // (1) add a STATIC flag to the class definition
1675 // if the current environment is static
1676 // (2) add an extends or implements clause
1677 // (3) add a constructor.
1678 //
1679 // For instance, if C is a class, and ET is the type of E,
1680 // the expression
1681 //
1682 // E.new <typeargs1>C<typargs2>(args) { ... }
1683 //
1684 // is translated to (where X is a fresh name and typarams is the
1685 // parameter list of the super constructor):
1686 //
1687 // new <typeargs1>X(<*nullchk*>E, args) where
1688 // X extends C<typargs2> {
1689 // <typarams> X(ET e, args) {
1690 // e.<typeargs1>super(args)
1691 // }
1692 // ...
1693 // }
1694 if (Resolve.isStatic(env)) cdef.mods.flags |= STATIC;
1696 if (clazztype.tsym.isInterface()) {
1697 cdef.implementing = List.of(clazz);
1698 } else {
1699 cdef.extending = clazz;
1700 }
1702 attribStat(cdef, localEnv);
1704 // If an outer instance is given,
1705 // prefix it to the constructor arguments
1706 // and delete it from the new expression
1707 if (tree.encl != null && !clazztype.tsym.isInterface()) {
1708 tree.args = tree.args.prepend(makeNullCheck(tree.encl));
1709 argtypes = argtypes.prepend(tree.encl.type);
1710 tree.encl = null;
1711 }
1713 // Reassign clazztype and recompute constructor.
1714 clazztype = cdef.sym.type;
1715 Symbol sym = rs.resolveConstructor(
1716 tree.pos(), localEnv, clazztype, argtypes,
1717 typeargtypes, true, tree.varargsElement != null);
1718 Assert.check(sym.kind < AMBIGUOUS || tree.constructor.type.isErroneous());
1719 tree.constructor = sym;
1720 if (tree.constructor.kind > ERRONEOUS) {
1721 tree.constructorType = syms.errType;
1722 }
1723 else {
1724 tree.constructorType = checkMethod(clazztype,
1725 tree.constructor,
1726 localEnv,
1727 tree.args,
1728 argtypes,
1729 typeargtypes,
1730 localEnv.info.varArgs);
1731 }
1732 }
1734 if (tree.constructor != null && tree.constructor.kind == MTH)
1735 owntype = clazztype;
1736 }
1737 result = check(tree, owntype, VAL, pkind, pt);
1738 chk.validate(tree.typeargs, localEnv);
1739 }
1741 Type attribDiamond(Env<AttrContext> env,
1742 JCNewClass tree,
1743 Type clazztype,
1744 Pair<Scope, Scope> mapping,
1745 List<Type> argtypes,
1746 List<Type> typeargtypes) {
1747 if (clazztype.isErroneous() || mapping == erroneousMapping) {
1748 //if the type of the instance creation expression is erroneous,
1749 //or something prevented us to form a valid mapping, return the
1750 //(possibly erroneous) type unchanged
1751 return clazztype;
1752 }
1753 else if (clazztype.isInterface()) {
1754 //if the type of the instance creation expression is an interface
1755 //skip the method resolution step (JLS 15.12.2.7). The type to be
1756 //inferred is of the kind <X1,X2, ... Xn>C<X1,X2, ... Xn>
1757 clazztype = new ForAll(clazztype.tsym.type.allparams(), clazztype.tsym.type) {
1758 @Override
1759 public List<Type> getConstraints(TypeVar tv, ConstraintKind ck) {
1760 switch (ck) {
1761 case EXTENDS: return types.getBounds(tv);
1762 default: return List.nil();
1763 }
1764 }
1765 @Override
1766 public Type inst(List<Type> inferred, Types types) throws Infer.NoInstanceException {
1767 // check that inferred bounds conform to their bounds
1768 infer.checkWithinBounds(tvars,
1769 types.subst(tvars, tvars, inferred), Warner.noWarnings);
1770 return super.inst(inferred, types);
1771 }
1772 };
1773 } else {
1774 //if the type of the instance creation expression is a class type
1775 //apply method resolution inference (JLS 15.12.2.7). The return type
1776 //of the resolved constructor will be a partially instantiated type
1777 ((ClassSymbol) clazztype.tsym).members_field = mapping.snd;
1778 Symbol constructor;
1779 try {
1780 constructor = rs.resolveDiamond(tree.pos(),
1781 env,
1782 clazztype.tsym.type,
1783 argtypes,
1784 typeargtypes);
1785 } finally {
1786 ((ClassSymbol) clazztype.tsym).members_field = mapping.fst;
1787 }
1788 if (constructor.kind == MTH) {
1789 ClassType ct = new ClassType(clazztype.getEnclosingType(),
1790 clazztype.tsym.type.getTypeArguments(),
1791 clazztype.tsym);
1792 clazztype = checkMethod(ct,
1793 constructor,
1794 env,
1795 tree.args,
1796 argtypes,
1797 typeargtypes,
1798 env.info.varArgs).getReturnType();
1799 } else {
1800 clazztype = syms.errType;
1801 }
1802 }
1803 if (clazztype.tag == FORALL && !pt.isErroneous()) {
1804 //if the resolved constructor's return type has some uninferred
1805 //type-variables, infer them using the expected type and declared
1806 //bounds (JLS 15.12.2.8).
1807 try {
1808 clazztype = infer.instantiateExpr((ForAll) clazztype,
1809 pt.tag == NONE ? syms.objectType : pt,
1810 Warner.noWarnings);
1811 } catch (Infer.InferenceException ex) {
1812 //an error occurred while inferring uninstantiated type-variables
1813 log.error(tree.clazz.pos(),
1814 "cant.apply.diamond.1",
1815 diags.fragment("diamond", clazztype.tsym),
1816 ex.diagnostic);
1817 }
1818 }
1819 clazztype = chk.checkClassType(tree.clazz.pos(),
1820 clazztype,
1821 true);
1822 if (clazztype.tag == CLASS) {
1823 List<Type> invalidDiamondArgs = chk.checkDiamond((ClassType)clazztype);
1824 if (!clazztype.isErroneous() && invalidDiamondArgs.nonEmpty()) {
1825 //one or more types inferred in the previous steps is either a
1826 //captured type or an intersection type --- we need to report an error.
1827 String subkey = invalidDiamondArgs.size() > 1 ?
1828 "diamond.invalid.args" :
1829 "diamond.invalid.arg";
1830 //The error message is of the kind:
1831 //
1832 //cannot infer type arguments for {clazztype}<>;
1833 //reason: {subkey}
1834 //
1835 //where subkey is a fragment of the kind:
1836 //
1837 //type argument(s) {invalidDiamondArgs} inferred for {clazztype}<> is not allowed in this context
1838 log.error(tree.clazz.pos(),
1839 "cant.apply.diamond.1",
1840 diags.fragment("diamond", clazztype.tsym),
1841 diags.fragment(subkey,
1842 invalidDiamondArgs,
1843 diags.fragment("diamond", clazztype.tsym)));
1844 }
1845 }
1846 return clazztype;
1847 }
1849 /** Creates a synthetic scope containing fake generic constructors.
1850 * Assuming that the original scope contains a constructor of the kind:
1851 * Foo(X x, Y y), where X,Y are class type-variables declared in Foo,
1852 * the synthetic scope is added a generic constructor of the kind:
1853 * <X,Y>Foo<X,Y>(X x, Y y). This is crucial in order to enable diamond
1854 * inference. The inferred return type of the synthetic constructor IS
1855 * the inferred type for the diamond operator.
1856 */
1857 private Pair<Scope, Scope> getSyntheticScopeMapping(Type ctype, boolean overrideProtectedAccess) {
1858 if (ctype.tag != CLASS) {
1859 return erroneousMapping;
1860 }
1861 Pair<Scope, Scope> mapping =
1862 new Pair<Scope, Scope>(ctype.tsym.members(), new Scope(ctype.tsym));
1863 List<Type> typevars = ctype.tsym.type.getTypeArguments();
1864 for (Scope.Entry e = mapping.fst.lookup(names.init);
1865 e.scope != null;
1866 e = e.next()) {
1867 MethodSymbol newConstr = (MethodSymbol) e.sym.clone(ctype.tsym);
1868 if (overrideProtectedAccess && (newConstr.flags() & PROTECTED) != 0) {
1869 //make protected constructor public (this is required for
1870 //anonymous inner class creation expressions using diamond)
1871 newConstr.flags_field |= PUBLIC;
1872 newConstr.flags_field &= ~PROTECTED;
1873 }
1874 newConstr.name = names.init;
1875 List<Type> oldTypeargs = List.nil();
1876 if (newConstr.type.tag == FORALL) {
1877 oldTypeargs = ((ForAll) newConstr.type).tvars;
1878 }
1879 newConstr.type = new MethodType(newConstr.type.getParameterTypes(),
1880 new ClassType(ctype.getEnclosingType(), ctype.tsym.type.getTypeArguments(), ctype.tsym),
1881 newConstr.type.getThrownTypes(),
1882 syms.methodClass);
1883 newConstr.type = new ForAll(typevars.prependList(oldTypeargs), newConstr.type);
1884 mapping.snd.enter(newConstr);
1885 }
1886 return mapping;
1887 }
1889 private final Pair<Scope,Scope> erroneousMapping = new Pair<Scope,Scope>(null, null);
1891 /** Make an attributed null check tree.
1892 */
1893 public JCExpression makeNullCheck(JCExpression arg) {
1894 // optimization: X.this is never null; skip null check
1895 Name name = TreeInfo.name(arg);
1896 if (name == names._this || name == names._super) return arg;
1898 int optag = JCTree.NULLCHK;
1899 JCUnary tree = make.at(arg.pos).Unary(optag, arg);
1900 tree.operator = syms.nullcheck;
1901 tree.type = arg.type;
1902 return tree;
1903 }
1905 public void visitNewArray(JCNewArray tree) {
1906 Type owntype = types.createErrorType(tree.type);
1907 Type elemtype;
1908 if (tree.elemtype != null) {
1909 elemtype = attribType(tree.elemtype, env);
1910 chk.validate(tree.elemtype, env);
1911 owntype = elemtype;
1912 for (List<JCExpression> l = tree.dims; l.nonEmpty(); l = l.tail) {
1913 attribExpr(l.head, env, syms.intType);
1914 owntype = new ArrayType(owntype, syms.arrayClass);
1915 }
1916 } else {
1917 // we are seeing an untyped aggregate { ... }
1918 // this is allowed only if the prototype is an array
1919 if (pt.tag == ARRAY) {
1920 elemtype = types.elemtype(pt);
1921 } else {
1922 if (pt.tag != ERROR) {
1923 log.error(tree.pos(), "illegal.initializer.for.type",
1924 pt);
1925 }
1926 elemtype = types.createErrorType(pt);
1927 }
1928 }
1929 if (tree.elems != null) {
1930 attribExprs(tree.elems, env, elemtype);
1931 owntype = new ArrayType(elemtype, syms.arrayClass);
1932 }
1933 if (!types.isReifiable(elemtype))
1934 log.error(tree.pos(), "generic.array.creation");
1935 result = check(tree, owntype, VAL, pkind, pt);
1936 }
1938 public void visitParens(JCParens tree) {
1939 Type owntype = attribTree(tree.expr, env, pkind, pt);
1940 result = check(tree, owntype, pkind, pkind, pt);
1941 Symbol sym = TreeInfo.symbol(tree);
1942 if (sym != null && (sym.kind&(TYP|PCK)) != 0)
1943 log.error(tree.pos(), "illegal.start.of.type");
1944 }
1946 public void visitAssign(JCAssign tree) {
1947 Type owntype = attribTree(tree.lhs, env.dup(tree), VAR, Type.noType);
1948 Type capturedType = capture(owntype);
1949 attribExpr(tree.rhs, env, owntype);
1950 result = check(tree, capturedType, VAL, pkind, pt);
1951 }
1953 public void visitAssignop(JCAssignOp tree) {
1954 // Attribute arguments.
1955 Type owntype = attribTree(tree.lhs, env, VAR, Type.noType);
1956 Type operand = attribExpr(tree.rhs, env);
1957 // Find operator.
1958 Symbol operator = tree.operator = rs.resolveBinaryOperator(
1959 tree.pos(), tree.getTag() - JCTree.ASGOffset, env,
1960 owntype, operand);
1962 if (operator.kind == MTH) {
1963 chk.checkOperator(tree.pos(),
1964 (OperatorSymbol)operator,
1965 tree.getTag() - JCTree.ASGOffset,
1966 owntype,
1967 operand);
1968 chk.checkDivZero(tree.rhs.pos(), operator, operand);
1969 chk.checkCastable(tree.rhs.pos(),
1970 operator.type.getReturnType(),
1971 owntype);
1972 }
1973 result = check(tree, owntype, VAL, pkind, pt);
1974 }
1976 public void visitUnary(JCUnary tree) {
1977 // Attribute arguments.
1978 Type argtype = (JCTree.PREINC <= tree.getTag() && tree.getTag() <= JCTree.POSTDEC)
1979 ? attribTree(tree.arg, env, VAR, Type.noType)
1980 : chk.checkNonVoid(tree.arg.pos(), attribExpr(tree.arg, env));
1982 // Find operator.
1983 Symbol operator = tree.operator =
1984 rs.resolveUnaryOperator(tree.pos(), tree.getTag(), env, argtype);
1986 Type owntype = types.createErrorType(tree.type);
1987 if (operator.kind == MTH) {
1988 owntype = (JCTree.PREINC <= tree.getTag() && tree.getTag() <= JCTree.POSTDEC)
1989 ? tree.arg.type
1990 : operator.type.getReturnType();
1991 int opc = ((OperatorSymbol)operator).opcode;
1993 // If the argument is constant, fold it.
1994 if (argtype.constValue() != null) {
1995 Type ctype = cfolder.fold1(opc, argtype);
1996 if (ctype != null) {
1997 owntype = cfolder.coerce(ctype, owntype);
1999 // Remove constant types from arguments to
2000 // conserve space. The parser will fold concatenations
2001 // of string literals; the code here also
2002 // gets rid of intermediate results when some of the
2003 // operands are constant identifiers.
2004 if (tree.arg.type.tsym == syms.stringType.tsym) {
2005 tree.arg.type = syms.stringType;
2006 }
2007 }
2008 }
2009 }
2010 result = check(tree, owntype, VAL, pkind, pt);
2011 }
2013 public void visitBinary(JCBinary tree) {
2014 // Attribute arguments.
2015 Type left = chk.checkNonVoid(tree.lhs.pos(), attribExpr(tree.lhs, env));
2016 Type right = chk.checkNonVoid(tree.lhs.pos(), attribExpr(tree.rhs, env));
2018 // Find operator.
2019 Symbol operator = tree.operator =
2020 rs.resolveBinaryOperator(tree.pos(), tree.getTag(), env, left, right);
2022 Type owntype = types.createErrorType(tree.type);
2023 if (operator.kind == MTH) {
2024 owntype = operator.type.getReturnType();
2025 int opc = chk.checkOperator(tree.lhs.pos(),
2026 (OperatorSymbol)operator,
2027 tree.getTag(),
2028 left,
2029 right);
2031 // If both arguments are constants, fold them.
2032 if (left.constValue() != null && right.constValue() != null) {
2033 Type ctype = cfolder.fold2(opc, left, right);
2034 if (ctype != null) {
2035 owntype = cfolder.coerce(ctype, owntype);
2037 // Remove constant types from arguments to
2038 // conserve space. The parser will fold concatenations
2039 // of string literals; the code here also
2040 // gets rid of intermediate results when some of the
2041 // operands are constant identifiers.
2042 if (tree.lhs.type.tsym == syms.stringType.tsym) {
2043 tree.lhs.type = syms.stringType;
2044 }
2045 if (tree.rhs.type.tsym == syms.stringType.tsym) {
2046 tree.rhs.type = syms.stringType;
2047 }
2048 }
2049 }
2051 // Check that argument types of a reference ==, != are
2052 // castable to each other, (JLS???).
2053 if ((opc == ByteCodes.if_acmpeq || opc == ByteCodes.if_acmpne)) {
2054 if (!types.isCastable(left, right, new Warner(tree.pos()))) {
2055 log.error(tree.pos(), "incomparable.types", left, right);
2056 }
2057 }
2059 chk.checkDivZero(tree.rhs.pos(), operator, right);
2060 }
2061 result = check(tree, owntype, VAL, pkind, pt);
2062 }
2064 public void visitTypeCast(JCTypeCast tree) {
2065 Type clazztype = attribType(tree.clazz, env);
2066 chk.validate(tree.clazz, env, false);
2067 //a fresh environment is required for 292 inference to work properly ---
2068 //see Infer.instantiatePolymorphicSignatureInstance()
2069 Env<AttrContext> localEnv = env.dup(tree);
2070 Type exprtype = attribExpr(tree.expr, localEnv, Infer.anyPoly);
2071 Type owntype = chk.checkCastable(tree.expr.pos(), exprtype, clazztype);
2072 if (exprtype.constValue() != null)
2073 owntype = cfolder.coerce(exprtype, owntype);
2074 result = check(tree, capture(owntype), VAL, pkind, pt);
2075 }
2077 public void visitTypeTest(JCInstanceOf tree) {
2078 Type exprtype = chk.checkNullOrRefType(
2079 tree.expr.pos(), attribExpr(tree.expr, env));
2080 Type clazztype = chk.checkReifiableReferenceType(
2081 tree.clazz.pos(), attribType(tree.clazz, env));
2082 chk.validate(tree.clazz, env, false);
2083 chk.checkCastable(tree.expr.pos(), exprtype, clazztype);
2084 result = check(tree, syms.booleanType, VAL, pkind, pt);
2085 }
2087 public void visitIndexed(JCArrayAccess tree) {
2088 Type owntype = types.createErrorType(tree.type);
2089 Type atype = attribExpr(tree.indexed, env);
2090 attribExpr(tree.index, env, syms.intType);
2091 if (types.isArray(atype))
2092 owntype = types.elemtype(atype);
2093 else if (atype.tag != ERROR)
2094 log.error(tree.pos(), "array.req.but.found", atype);
2095 if ((pkind & VAR) == 0) owntype = capture(owntype);
2096 result = check(tree, owntype, VAR, pkind, pt);
2097 }
2099 public void visitIdent(JCIdent tree) {
2100 Symbol sym;
2101 boolean varArgs = false;
2103 // Find symbol
2104 if (pt.tag == METHOD || pt.tag == FORALL) {
2105 // If we are looking for a method, the prototype `pt' will be a
2106 // method type with the type of the call's arguments as parameters.
2107 env.info.varArgs = false;
2108 sym = rs.resolveMethod(tree.pos(), env, tree.name, pt.getParameterTypes(), pt.getTypeArguments());
2109 varArgs = env.info.varArgs;
2110 } else if (tree.sym != null && tree.sym.kind != VAR) {
2111 sym = tree.sym;
2112 } else {
2113 sym = rs.resolveIdent(tree.pos(), env, tree.name, pkind);
2114 }
2115 tree.sym = sym;
2117 // (1) Also find the environment current for the class where
2118 // sym is defined (`symEnv').
2119 // Only for pre-tiger versions (1.4 and earlier):
2120 // (2) Also determine whether we access symbol out of an anonymous
2121 // class in a this or super call. This is illegal for instance
2122 // members since such classes don't carry a this$n link.
2123 // (`noOuterThisPath').
2124 Env<AttrContext> symEnv = env;
2125 boolean noOuterThisPath = false;
2126 if (env.enclClass.sym.owner.kind != PCK && // we are in an inner class
2127 (sym.kind & (VAR | MTH | TYP)) != 0 &&
2128 sym.owner.kind == TYP &&
2129 tree.name != names._this && tree.name != names._super) {
2131 // Find environment in which identifier is defined.
2132 while (symEnv.outer != null &&
2133 !sym.isMemberOf(symEnv.enclClass.sym, types)) {
2134 if ((symEnv.enclClass.sym.flags() & NOOUTERTHIS) != 0)
2135 noOuterThisPath = !allowAnonOuterThis;
2136 symEnv = symEnv.outer;
2137 }
2138 }
2140 // If symbol is a variable, ...
2141 if (sym.kind == VAR) {
2142 VarSymbol v = (VarSymbol)sym;
2144 // ..., evaluate its initializer, if it has one, and check for
2145 // illegal forward reference.
2146 checkInit(tree, env, v, false);
2148 // If symbol is a local variable accessed from an embedded
2149 // inner class check that it is final.
2150 if (v.owner.kind == MTH &&
2151 v.owner != env.info.scope.owner &&
2152 (v.flags_field & FINAL) == 0) {
2153 log.error(tree.pos(),
2154 "local.var.accessed.from.icls.needs.final",
2155 v);
2156 }
2158 // If we are expecting a variable (as opposed to a value), check
2159 // that the variable is assignable in the current environment.
2160 if (pkind == VAR)
2161 checkAssignable(tree.pos(), v, null, env);
2162 }
2164 // In a constructor body,
2165 // if symbol is a field or instance method, check that it is
2166 // not accessed before the supertype constructor is called.
2167 if ((symEnv.info.isSelfCall || noOuterThisPath) &&
2168 (sym.kind & (VAR | MTH)) != 0 &&
2169 sym.owner.kind == TYP &&
2170 (sym.flags() & STATIC) == 0) {
2171 chk.earlyRefError(tree.pos(), sym.kind == VAR ? sym : thisSym(tree.pos(), env));
2172 }
2173 Env<AttrContext> env1 = env;
2174 if (sym.kind != ERR && sym.kind != TYP && sym.owner != null && sym.owner != env1.enclClass.sym) {
2175 // If the found symbol is inaccessible, then it is
2176 // accessed through an enclosing instance. Locate this
2177 // enclosing instance:
2178 while (env1.outer != null && !rs.isAccessible(env, env1.enclClass.sym.type, sym))
2179 env1 = env1.outer;
2180 }
2181 result = checkId(tree, env1.enclClass.sym.type, sym, env, pkind, pt, varArgs);
2182 }
2184 public void visitSelect(JCFieldAccess tree) {
2185 // Determine the expected kind of the qualifier expression.
2186 int skind = 0;
2187 if (tree.name == names._this || tree.name == names._super ||
2188 tree.name == names._class)
2189 {
2190 skind = TYP;
2191 } else {
2192 if ((pkind & PCK) != 0) skind = skind | PCK;
2193 if ((pkind & TYP) != 0) skind = skind | TYP | PCK;
2194 if ((pkind & (VAL | MTH)) != 0) skind = skind | VAL | TYP;
2195 }
2197 // Attribute the qualifier expression, and determine its symbol (if any).
2198 Type site = attribTree(tree.selected, env, skind, Infer.anyPoly);
2199 if ((pkind & (PCK | TYP)) == 0)
2200 site = capture(site); // Capture field access
2202 // don't allow T.class T[].class, etc
2203 if (skind == TYP) {
2204 Type elt = site;
2205 while (elt.tag == ARRAY)
2206 elt = ((ArrayType)elt).elemtype;
2207 if (elt.tag == TYPEVAR) {
2208 log.error(tree.pos(), "type.var.cant.be.deref");
2209 result = types.createErrorType(tree.type);
2210 return;
2211 }
2212 }
2214 // If qualifier symbol is a type or `super', assert `selectSuper'
2215 // for the selection. This is relevant for determining whether
2216 // protected symbols are accessible.
2217 Symbol sitesym = TreeInfo.symbol(tree.selected);
2218 boolean selectSuperPrev = env.info.selectSuper;
2219 env.info.selectSuper =
2220 sitesym != null &&
2221 sitesym.name == names._super;
2223 // If selected expression is polymorphic, strip
2224 // type parameters and remember in env.info.tvars, so that
2225 // they can be added later (in Attr.checkId and Infer.instantiateMethod).
2226 if (tree.selected.type.tag == FORALL) {
2227 ForAll pstype = (ForAll)tree.selected.type;
2228 env.info.tvars = pstype.tvars;
2229 site = tree.selected.type = pstype.qtype;
2230 }
2232 // Determine the symbol represented by the selection.
2233 env.info.varArgs = false;
2234 Symbol sym = selectSym(tree, sitesym, site, env, pt, pkind);
2235 if (sym.exists() && !isType(sym) && (pkind & (PCK | TYP)) != 0) {
2236 site = capture(site);
2237 sym = selectSym(tree, sitesym, site, env, pt, pkind);
2238 }
2239 boolean varArgs = env.info.varArgs;
2240 tree.sym = sym;
2242 if (site.tag == TYPEVAR && !isType(sym) && sym.kind != ERR) {
2243 while (site.tag == TYPEVAR) site = site.getUpperBound();
2244 site = capture(site);
2245 }
2247 // If that symbol is a variable, ...
2248 if (sym.kind == VAR) {
2249 VarSymbol v = (VarSymbol)sym;
2251 // ..., evaluate its initializer, if it has one, and check for
2252 // illegal forward reference.
2253 checkInit(tree, env, v, true);
2255 // If we are expecting a variable (as opposed to a value), check
2256 // that the variable is assignable in the current environment.
2257 if (pkind == VAR)
2258 checkAssignable(tree.pos(), v, tree.selected, env);
2259 }
2261 if (sitesym != null &&
2262 sitesym.kind == VAR &&
2263 ((VarSymbol)sitesym).isResourceVariable() &&
2264 sym.kind == MTH &&
2265 sym.overrides(syms.autoCloseableClose, sitesym.type.tsym, types, true) &&
2266 env.info.lint.isEnabled(LintCategory.TRY)) {
2267 log.warning(LintCategory.TRY, tree, "try.explicit.close.call");
2268 }
2270 // Disallow selecting a type from an expression
2271 if (isType(sym) && (sitesym==null || (sitesym.kind&(TYP|PCK)) == 0)) {
2272 tree.type = check(tree.selected, pt,
2273 sitesym == null ? VAL : sitesym.kind, TYP|PCK, pt);
2274 }
2276 if (isType(sitesym)) {
2277 if (sym.name == names._this) {
2278 // If `C' is the currently compiled class, check that
2279 // C.this' does not appear in a call to a super(...)
2280 if (env.info.isSelfCall &&
2281 site.tsym == env.enclClass.sym) {
2282 chk.earlyRefError(tree.pos(), sym);
2283 }
2284 } else {
2285 // Check if type-qualified fields or methods are static (JLS)
2286 if ((sym.flags() & STATIC) == 0 &&
2287 sym.name != names._super &&
2288 (sym.kind == VAR || sym.kind == MTH)) {
2289 rs.access(rs.new StaticError(sym),
2290 tree.pos(), site, sym.name, true);
2291 }
2292 }
2293 } else if (sym.kind != ERR && (sym.flags() & STATIC) != 0 && sym.name != names._class) {
2294 // If the qualified item is not a type and the selected item is static, report
2295 // a warning. Make allowance for the class of an array type e.g. Object[].class)
2296 chk.warnStatic(tree, "static.not.qualified.by.type", Kinds.kindName(sym.kind), sym.owner);
2297 }
2299 // If we are selecting an instance member via a `super', ...
2300 if (env.info.selectSuper && (sym.flags() & STATIC) == 0) {
2302 // Check that super-qualified symbols are not abstract (JLS)
2303 rs.checkNonAbstract(tree.pos(), sym);
2305 if (site.isRaw()) {
2306 // Determine argument types for site.
2307 Type site1 = types.asSuper(env.enclClass.sym.type, site.tsym);
2308 if (site1 != null) site = site1;
2309 }
2310 }
2312 env.info.selectSuper = selectSuperPrev;
2313 result = checkId(tree, site, sym, env, pkind, pt, varArgs);
2314 env.info.tvars = List.nil();
2315 }
2316 //where
2317 /** Determine symbol referenced by a Select expression,
2318 *
2319 * @param tree The select tree.
2320 * @param site The type of the selected expression,
2321 * @param env The current environment.
2322 * @param pt The current prototype.
2323 * @param pkind The expected kind(s) of the Select expression.
2324 */
2325 private Symbol selectSym(JCFieldAccess tree,
2326 Type site,
2327 Env<AttrContext> env,
2328 Type pt,
2329 int pkind) {
2330 return selectSym(tree, site.tsym, site, env, pt, pkind);
2331 }
2332 private Symbol selectSym(JCFieldAccess tree,
2333 Symbol location,
2334 Type site,
2335 Env<AttrContext> env,
2336 Type pt,
2337 int pkind) {
2338 DiagnosticPosition pos = tree.pos();
2339 Name name = tree.name;
2341 switch (site.tag) {
2342 case PACKAGE:
2343 return rs.access(
2344 rs.findIdentInPackage(env, site.tsym, name, pkind),
2345 pos, location, site, name, true);
2346 case ARRAY:
2347 case CLASS:
2348 if (pt.tag == METHOD || pt.tag == FORALL) {
2349 return rs.resolveQualifiedMethod(
2350 pos, env, location, site, name, pt.getParameterTypes(), pt.getTypeArguments());
2351 } else if (name == names._this || name == names._super) {
2352 return rs.resolveSelf(pos, env, site.tsym, name);
2353 } else if (name == names._class) {
2354 // In this case, we have already made sure in
2355 // visitSelect that qualifier expression is a type.
2356 Type t = syms.classType;
2357 List<Type> typeargs = allowGenerics
2358 ? List.of(types.erasure(site))
2359 : List.<Type>nil();
2360 t = new ClassType(t.getEnclosingType(), typeargs, t.tsym);
2361 return new VarSymbol(
2362 STATIC | PUBLIC | FINAL, names._class, t, site.tsym);
2363 } else {
2364 // We are seeing a plain identifier as selector.
2365 Symbol sym = rs.findIdentInType(env, site, name, pkind);
2366 if ((pkind & ERRONEOUS) == 0)
2367 sym = rs.access(sym, pos, location, site, name, true);
2368 return sym;
2369 }
2370 case WILDCARD:
2371 throw new AssertionError(tree);
2372 case TYPEVAR:
2373 // Normally, site.getUpperBound() shouldn't be null.
2374 // It should only happen during memberEnter/attribBase
2375 // when determining the super type which *must* beac
2376 // done before attributing the type variables. In
2377 // other words, we are seeing this illegal program:
2378 // class B<T> extends A<T.foo> {}
2379 Symbol sym = (site.getUpperBound() != null)
2380 ? selectSym(tree, location, capture(site.getUpperBound()), env, pt, pkind)
2381 : null;
2382 if (sym == null) {
2383 log.error(pos, "type.var.cant.be.deref");
2384 return syms.errSymbol;
2385 } else {
2386 Symbol sym2 = (sym.flags() & Flags.PRIVATE) != 0 ?
2387 rs.new AccessError(env, site, sym) :
2388 sym;
2389 rs.access(sym2, pos, location, site, name, true);
2390 return sym;
2391 }
2392 case ERROR:
2393 // preserve identifier names through errors
2394 return types.createErrorType(name, site.tsym, site).tsym;
2395 default:
2396 // The qualifier expression is of a primitive type -- only
2397 // .class is allowed for these.
2398 if (name == names._class) {
2399 // In this case, we have already made sure in Select that
2400 // qualifier expression is a type.
2401 Type t = syms.classType;
2402 Type arg = types.boxedClass(site).type;
2403 t = new ClassType(t.getEnclosingType(), List.of(arg), t.tsym);
2404 return new VarSymbol(
2405 STATIC | PUBLIC | FINAL, names._class, t, site.tsym);
2406 } else {
2407 log.error(pos, "cant.deref", site);
2408 return syms.errSymbol;
2409 }
2410 }
2411 }
2413 /** Determine type of identifier or select expression and check that
2414 * (1) the referenced symbol is not deprecated
2415 * (2) the symbol's type is safe (@see checkSafe)
2416 * (3) if symbol is a variable, check that its type and kind are
2417 * compatible with the prototype and protokind.
2418 * (4) if symbol is an instance field of a raw type,
2419 * which is being assigned to, issue an unchecked warning if its
2420 * type changes under erasure.
2421 * (5) if symbol is an instance method of a raw type, issue an
2422 * unchecked warning if its argument types change under erasure.
2423 * If checks succeed:
2424 * If symbol is a constant, return its constant type
2425 * else if symbol is a method, return its result type
2426 * otherwise return its type.
2427 * Otherwise return errType.
2428 *
2429 * @param tree The syntax tree representing the identifier
2430 * @param site If this is a select, the type of the selected
2431 * expression, otherwise the type of the current class.
2432 * @param sym The symbol representing the identifier.
2433 * @param env The current environment.
2434 * @param pkind The set of expected kinds.
2435 * @param pt The expected type.
2436 */
2437 Type checkId(JCTree tree,
2438 Type site,
2439 Symbol sym,
2440 Env<AttrContext> env,
2441 int pkind,
2442 Type pt,
2443 boolean useVarargs) {
2444 if (pt.isErroneous()) return types.createErrorType(site);
2445 Type owntype; // The computed type of this identifier occurrence.
2446 switch (sym.kind) {
2447 case TYP:
2448 // For types, the computed type equals the symbol's type,
2449 // except for two situations:
2450 owntype = sym.type;
2451 if (owntype.tag == CLASS) {
2452 Type ownOuter = owntype.getEnclosingType();
2454 // (a) If the symbol's type is parameterized, erase it
2455 // because no type parameters were given.
2456 // We recover generic outer type later in visitTypeApply.
2457 if (owntype.tsym.type.getTypeArguments().nonEmpty()) {
2458 owntype = types.erasure(owntype);
2459 }
2461 // (b) If the symbol's type is an inner class, then
2462 // we have to interpret its outer type as a superclass
2463 // of the site type. Example:
2464 //
2465 // class Tree<A> { class Visitor { ... } }
2466 // class PointTree extends Tree<Point> { ... }
2467 // ...PointTree.Visitor...
2468 //
2469 // Then the type of the last expression above is
2470 // Tree<Point>.Visitor.
2471 else if (ownOuter.tag == CLASS && site != ownOuter) {
2472 Type normOuter = site;
2473 if (normOuter.tag == CLASS)
2474 normOuter = types.asEnclosingSuper(site, ownOuter.tsym);
2475 if (normOuter == null) // perhaps from an import
2476 normOuter = types.erasure(ownOuter);
2477 if (normOuter != ownOuter)
2478 owntype = new ClassType(
2479 normOuter, List.<Type>nil(), owntype.tsym);
2480 }
2481 }
2482 break;
2483 case VAR:
2484 VarSymbol v = (VarSymbol)sym;
2485 // Test (4): if symbol is an instance field of a raw type,
2486 // which is being assigned to, issue an unchecked warning if
2487 // its type changes under erasure.
2488 if (allowGenerics &&
2489 pkind == VAR &&
2490 v.owner.kind == TYP &&
2491 (v.flags() & STATIC) == 0 &&
2492 (site.tag == CLASS || site.tag == TYPEVAR)) {
2493 Type s = types.asOuterSuper(site, v.owner);
2494 if (s != null &&
2495 s.isRaw() &&
2496 !types.isSameType(v.type, v.erasure(types))) {
2497 chk.warnUnchecked(tree.pos(),
2498 "unchecked.assign.to.var",
2499 v, s);
2500 }
2501 }
2502 // The computed type of a variable is the type of the
2503 // variable symbol, taken as a member of the site type.
2504 owntype = (sym.owner.kind == TYP &&
2505 sym.name != names._this && sym.name != names._super)
2506 ? types.memberType(site, sym)
2507 : sym.type;
2509 if (env.info.tvars.nonEmpty()) {
2510 Type owntype1 = new ForAll(env.info.tvars, owntype);
2511 for (List<Type> l = env.info.tvars; l.nonEmpty(); l = l.tail)
2512 if (!owntype.contains(l.head)) {
2513 log.error(tree.pos(), "undetermined.type", owntype1);
2514 owntype1 = types.createErrorType(owntype1);
2515 }
2516 owntype = owntype1;
2517 }
2519 // If the variable is a constant, record constant value in
2520 // computed type.
2521 if (v.getConstValue() != null && isStaticReference(tree))
2522 owntype = owntype.constType(v.getConstValue());
2524 if (pkind == VAL) {
2525 owntype = capture(owntype); // capture "names as expressions"
2526 }
2527 break;
2528 case MTH: {
2529 JCMethodInvocation app = (JCMethodInvocation)env.tree;
2530 owntype = checkMethod(site, sym, env, app.args,
2531 pt.getParameterTypes(), pt.getTypeArguments(),
2532 env.info.varArgs);
2533 break;
2534 }
2535 case PCK: case ERR:
2536 owntype = sym.type;
2537 break;
2538 default:
2539 throw new AssertionError("unexpected kind: " + sym.kind +
2540 " in tree " + tree);
2541 }
2543 // Test (1): emit a `deprecation' warning if symbol is deprecated.
2544 // (for constructors, the error was given when the constructor was
2545 // resolved)
2546 if (sym.name != names.init &&
2547 (sym.flags() & DEPRECATED) != 0 &&
2548 (env.info.scope.owner.flags() & DEPRECATED) == 0 &&
2549 sym.outermostClass() != env.info.scope.owner.outermostClass())
2550 chk.warnDeprecated(tree.pos(), sym);
2552 if ((sym.flags() & PROPRIETARY) != 0) {
2553 if (enableSunApiLintControl)
2554 chk.warnSunApi(tree.pos(), "sun.proprietary", sym);
2555 else
2556 log.strictWarning(tree.pos(), "sun.proprietary", sym);
2557 }
2559 // Test (3): if symbol is a variable, check that its type and
2560 // kind are compatible with the prototype and protokind.
2561 return check(tree, owntype, sym.kind, pkind, pt);
2562 }
2564 /** Check that variable is initialized and evaluate the variable's
2565 * initializer, if not yet done. Also check that variable is not
2566 * referenced before it is defined.
2567 * @param tree The tree making up the variable reference.
2568 * @param env The current environment.
2569 * @param v The variable's symbol.
2570 */
2571 private void checkInit(JCTree tree,
2572 Env<AttrContext> env,
2573 VarSymbol v,
2574 boolean onlyWarning) {
2575 // System.err.println(v + " " + ((v.flags() & STATIC) != 0) + " " +
2576 // tree.pos + " " + v.pos + " " +
2577 // Resolve.isStatic(env));//DEBUG
2579 // A forward reference is diagnosed if the declaration position
2580 // of the variable is greater than the current tree position
2581 // and the tree and variable definition occur in the same class
2582 // definition. Note that writes don't count as references.
2583 // This check applies only to class and instance
2584 // variables. Local variables follow different scope rules,
2585 // and are subject to definite assignment checking.
2586 if ((env.info.enclVar == v || v.pos > tree.pos) &&
2587 v.owner.kind == TYP &&
2588 canOwnInitializer(env.info.scope.owner) &&
2589 v.owner == env.info.scope.owner.enclClass() &&
2590 ((v.flags() & STATIC) != 0) == Resolve.isStatic(env) &&
2591 (env.tree.getTag() != JCTree.ASSIGN ||
2592 TreeInfo.skipParens(((JCAssign) env.tree).lhs) != tree)) {
2593 String suffix = (env.info.enclVar == v) ?
2594 "self.ref" : "forward.ref";
2595 if (!onlyWarning || isStaticEnumField(v)) {
2596 log.error(tree.pos(), "illegal." + suffix);
2597 } else if (useBeforeDeclarationWarning) {
2598 log.warning(tree.pos(), suffix, v);
2599 }
2600 }
2602 v.getConstValue(); // ensure initializer is evaluated
2604 checkEnumInitializer(tree, env, v);
2605 }
2607 /**
2608 * Check for illegal references to static members of enum. In
2609 * an enum type, constructors and initializers may not
2610 * reference its static members unless they are constant.
2611 *
2612 * @param tree The tree making up the variable reference.
2613 * @param env The current environment.
2614 * @param v The variable's symbol.
2615 * @see JLS 3rd Ed. (8.9 Enums)
2616 */
2617 private void checkEnumInitializer(JCTree tree, Env<AttrContext> env, VarSymbol v) {
2618 // JLS 3rd Ed.:
2619 //
2620 // "It is a compile-time error to reference a static field
2621 // of an enum type that is not a compile-time constant
2622 // (15.28) from constructors, instance initializer blocks,
2623 // or instance variable initializer expressions of that
2624 // type. It is a compile-time error for the constructors,
2625 // instance initializer blocks, or instance variable
2626 // initializer expressions of an enum constant e to refer
2627 // to itself or to an enum constant of the same type that
2628 // is declared to the right of e."
2629 if (isStaticEnumField(v)) {
2630 ClassSymbol enclClass = env.info.scope.owner.enclClass();
2632 if (enclClass == null || enclClass.owner == null)
2633 return;
2635 // See if the enclosing class is the enum (or a
2636 // subclass thereof) declaring v. If not, this
2637 // reference is OK.
2638 if (v.owner != enclClass && !types.isSubtype(enclClass.type, v.owner.type))
2639 return;
2641 // If the reference isn't from an initializer, then
2642 // the reference is OK.
2643 if (!Resolve.isInitializer(env))
2644 return;
2646 log.error(tree.pos(), "illegal.enum.static.ref");
2647 }
2648 }
2650 /** Is the given symbol a static, non-constant field of an Enum?
2651 * Note: enum literals should not be regarded as such
2652 */
2653 private boolean isStaticEnumField(VarSymbol v) {
2654 return Flags.isEnum(v.owner) &&
2655 Flags.isStatic(v) &&
2656 !Flags.isConstant(v) &&
2657 v.name != names._class;
2658 }
2660 /** Can the given symbol be the owner of code which forms part
2661 * if class initialization? This is the case if the symbol is
2662 * a type or field, or if the symbol is the synthetic method.
2663 * owning a block.
2664 */
2665 private boolean canOwnInitializer(Symbol sym) {
2666 return
2667 (sym.kind & (VAR | TYP)) != 0 ||
2668 (sym.kind == MTH && (sym.flags() & BLOCK) != 0);
2669 }
2671 Warner noteWarner = new Warner();
2673 /**
2674 * Check that method arguments conform to its instantation.
2675 **/
2676 public Type checkMethod(Type site,
2677 Symbol sym,
2678 Env<AttrContext> env,
2679 final List<JCExpression> argtrees,
2680 List<Type> argtypes,
2681 List<Type> typeargtypes,
2682 boolean useVarargs) {
2683 // Test (5): if symbol is an instance method of a raw type, issue
2684 // an unchecked warning if its argument types change under erasure.
2685 if (allowGenerics &&
2686 (sym.flags() & STATIC) == 0 &&
2687 (site.tag == CLASS || site.tag == TYPEVAR)) {
2688 Type s = types.asOuterSuper(site, sym.owner);
2689 if (s != null && s.isRaw() &&
2690 !types.isSameTypes(sym.type.getParameterTypes(),
2691 sym.erasure(types).getParameterTypes())) {
2692 chk.warnUnchecked(env.tree.pos(),
2693 "unchecked.call.mbr.of.raw.type",
2694 sym, s);
2695 }
2696 }
2698 // Compute the identifier's instantiated type.
2699 // For methods, we need to compute the instance type by
2700 // Resolve.instantiate from the symbol's type as well as
2701 // any type arguments and value arguments.
2702 noteWarner.clear();
2703 Type owntype = rs.instantiate(env,
2704 site,
2705 sym,
2706 argtypes,
2707 typeargtypes,
2708 true,
2709 useVarargs,
2710 noteWarner);
2711 boolean warned = noteWarner.hasNonSilentLint(LintCategory.UNCHECKED);
2713 // If this fails, something went wrong; we should not have
2714 // found the identifier in the first place.
2715 if (owntype == null) {
2716 if (!pt.isErroneous())
2717 log.error(env.tree.pos(),
2718 "internal.error.cant.instantiate",
2719 sym, site,
2720 Type.toString(pt.getParameterTypes()));
2721 owntype = types.createErrorType(site);
2722 } else {
2723 // System.out.println("call : " + env.tree);
2724 // System.out.println("method : " + owntype);
2725 // System.out.println("actuals: " + argtypes);
2726 List<Type> formals = owntype.getParameterTypes();
2727 Type last = useVarargs ? formals.last() : null;
2728 if (sym.name==names.init &&
2729 sym.owner == syms.enumSym)
2730 formals = formals.tail.tail;
2731 List<JCExpression> args = argtrees;
2732 while (formals.head != last) {
2733 JCTree arg = args.head;
2734 Warner warn = chk.convertWarner(arg.pos(), arg.type, formals.head);
2735 assertConvertible(arg, arg.type, formals.head, warn);
2736 warned |= warn.hasNonSilentLint(LintCategory.UNCHECKED);
2737 args = args.tail;
2738 formals = formals.tail;
2739 }
2740 if (useVarargs) {
2741 Type varArg = types.elemtype(last);
2742 while (args.tail != null) {
2743 JCTree arg = args.head;
2744 Warner warn = chk.convertWarner(arg.pos(), arg.type, varArg);
2745 assertConvertible(arg, arg.type, varArg, warn);
2746 warned |= warn.hasNonSilentLint(LintCategory.UNCHECKED);
2747 args = args.tail;
2748 }
2749 } else if ((sym.flags() & VARARGS) != 0 && allowVarargs) {
2750 // non-varargs call to varargs method
2751 Type varParam = owntype.getParameterTypes().last();
2752 Type lastArg = argtypes.last();
2753 if (types.isSubtypeUnchecked(lastArg, types.elemtype(varParam)) &&
2754 !types.isSameType(types.erasure(varParam), types.erasure(lastArg)))
2755 log.warning(argtrees.last().pos(), "inexact.non-varargs.call",
2756 types.elemtype(varParam),
2757 varParam);
2758 }
2760 if (warned && sym.type.tag == FORALL) {
2761 chk.warnUnchecked(env.tree.pos(),
2762 "unchecked.meth.invocation.applied",
2763 kindName(sym),
2764 sym.name,
2765 rs.methodArguments(sym.type.getParameterTypes()),
2766 rs.methodArguments(argtypes),
2767 kindName(sym.location()),
2768 sym.location());
2769 owntype = new MethodType(owntype.getParameterTypes(),
2770 types.erasure(owntype.getReturnType()),
2771 owntype.getThrownTypes(),
2772 syms.methodClass);
2773 }
2774 if (useVarargs) {
2775 JCTree tree = env.tree;
2776 Type argtype = owntype.getParameterTypes().last();
2777 if (owntype.getReturnType().tag != FORALL || warned) {
2778 chk.checkVararg(env.tree.pos(), owntype.getParameterTypes(), sym);
2779 }
2780 Type elemtype = types.elemtype(argtype);
2781 switch (tree.getTag()) {
2782 case JCTree.APPLY:
2783 ((JCMethodInvocation) tree).varargsElement = elemtype;
2784 break;
2785 case JCTree.NEWCLASS:
2786 ((JCNewClass) tree).varargsElement = elemtype;
2787 break;
2788 default:
2789 throw new AssertionError(""+tree);
2790 }
2791 }
2792 }
2793 return owntype;
2794 }
2796 private void assertConvertible(JCTree tree, Type actual, Type formal, Warner warn) {
2797 if (types.isConvertible(actual, formal, warn))
2798 return;
2800 if (formal.isCompound()
2801 && types.isSubtype(actual, types.supertype(formal))
2802 && types.isSubtypeUnchecked(actual, types.interfaces(formal), warn))
2803 return;
2805 if (false) {
2806 // TODO: make assertConvertible work
2807 chk.typeError(tree.pos(), diags.fragment("incompatible.types"), actual, formal);
2808 throw new AssertionError("Tree: " + tree
2809 + " actual:" + actual
2810 + " formal: " + formal);
2811 }
2812 }
2814 public void visitLiteral(JCLiteral tree) {
2815 result = check(
2816 tree, litType(tree.typetag).constType(tree.value), VAL, pkind, pt);
2817 }
2818 //where
2819 /** Return the type of a literal with given type tag.
2820 */
2821 Type litType(int tag) {
2822 return (tag == TypeTags.CLASS) ? syms.stringType : syms.typeOfTag[tag];
2823 }
2825 public void visitTypeIdent(JCPrimitiveTypeTree tree) {
2826 result = check(tree, syms.typeOfTag[tree.typetag], TYP, pkind, pt);
2827 }
2829 public void visitTypeArray(JCArrayTypeTree tree) {
2830 Type etype = attribType(tree.elemtype, env);
2831 Type type = new ArrayType(etype, syms.arrayClass);
2832 result = check(tree, type, TYP, pkind, pt);
2833 }
2835 /** Visitor method for parameterized types.
2836 * Bound checking is left until later, since types are attributed
2837 * before supertype structure is completely known
2838 */
2839 public void visitTypeApply(JCTypeApply tree) {
2840 Type owntype = types.createErrorType(tree.type);
2842 // Attribute functor part of application and make sure it's a class.
2843 Type clazztype = chk.checkClassType(tree.clazz.pos(), attribType(tree.clazz, env));
2845 // Attribute type parameters
2846 List<Type> actuals = attribTypes(tree.arguments, env);
2848 if (clazztype.tag == CLASS) {
2849 List<Type> formals = clazztype.tsym.type.getTypeArguments();
2851 if (actuals.length() == formals.length() || actuals.length() == 0) {
2852 List<Type> a = actuals;
2853 List<Type> f = formals;
2854 while (a.nonEmpty()) {
2855 a.head = a.head.withTypeVar(f.head);
2856 a = a.tail;
2857 f = f.tail;
2858 }
2859 // Compute the proper generic outer
2860 Type clazzOuter = clazztype.getEnclosingType();
2861 if (clazzOuter.tag == CLASS) {
2862 Type site;
2863 JCExpression clazz = TreeInfo.typeIn(tree.clazz);
2864 if (clazz.getTag() == JCTree.IDENT) {
2865 site = env.enclClass.sym.type;
2866 } else if (clazz.getTag() == JCTree.SELECT) {
2867 site = ((JCFieldAccess) clazz).selected.type;
2868 } else throw new AssertionError(""+tree);
2869 if (clazzOuter.tag == CLASS && site != clazzOuter) {
2870 if (site.tag == CLASS)
2871 site = types.asOuterSuper(site, clazzOuter.tsym);
2872 if (site == null)
2873 site = types.erasure(clazzOuter);
2874 clazzOuter = site;
2875 }
2876 }
2877 owntype = new ClassType(clazzOuter, actuals, clazztype.tsym);
2878 } else {
2879 if (formals.length() != 0) {
2880 log.error(tree.pos(), "wrong.number.type.args",
2881 Integer.toString(formals.length()));
2882 } else {
2883 log.error(tree.pos(), "type.doesnt.take.params", clazztype.tsym);
2884 }
2885 owntype = types.createErrorType(tree.type);
2886 }
2887 }
2888 result = check(tree, owntype, TYP, pkind, pt);
2889 }
2891 public void visitTypeDisjunction(JCTypeDisjunction tree) {
2892 ListBuffer<Type> multicatchTypes = ListBuffer.lb();
2893 for (JCExpression typeTree : tree.alternatives) {
2894 Type ctype = attribType(typeTree, env);
2895 ctype = chk.checkType(typeTree.pos(),
2896 chk.checkClassType(typeTree.pos(), ctype),
2897 syms.throwableType);
2898 multicatchTypes.append(ctype);
2899 }
2900 tree.type = result = check(tree, types.lub(multicatchTypes.toList()), TYP, pkind, pt);
2901 }
2903 public void visitTypeParameter(JCTypeParameter tree) {
2904 TypeVar a = (TypeVar)tree.type;
2905 Set<Type> boundSet = new HashSet<Type>();
2906 if (a.bound.isErroneous())
2907 return;
2908 List<Type> bs = types.getBounds(a);
2909 if (tree.bounds.nonEmpty()) {
2910 // accept class or interface or typevar as first bound.
2911 Type b = checkBase(bs.head, tree.bounds.head, env, false, false, false);
2912 boundSet.add(types.erasure(b));
2913 if (b.isErroneous()) {
2914 a.bound = b;
2915 }
2916 else if (b.tag == TYPEVAR) {
2917 // if first bound was a typevar, do not accept further bounds.
2918 if (tree.bounds.tail.nonEmpty()) {
2919 log.error(tree.bounds.tail.head.pos(),
2920 "type.var.may.not.be.followed.by.other.bounds");
2921 tree.bounds = List.of(tree.bounds.head);
2922 a.bound = bs.head;
2923 }
2924 } else {
2925 // if first bound was a class or interface, accept only interfaces
2926 // as further bounds.
2927 for (JCExpression bound : tree.bounds.tail) {
2928 bs = bs.tail;
2929 Type i = checkBase(bs.head, bound, env, false, true, false);
2930 if (i.isErroneous())
2931 a.bound = i;
2932 else if (i.tag == CLASS)
2933 chk.checkNotRepeated(bound.pos(), types.erasure(i), boundSet);
2934 }
2935 }
2936 }
2937 bs = types.getBounds(a);
2939 // in case of multiple bounds ...
2940 if (bs.length() > 1) {
2941 // ... the variable's bound is a class type flagged COMPOUND
2942 // (see comment for TypeVar.bound).
2943 // In this case, generate a class tree that represents the
2944 // bound class, ...
2945 JCTree extending;
2946 List<JCExpression> implementing;
2947 if ((bs.head.tsym.flags() & INTERFACE) == 0) {
2948 extending = tree.bounds.head;
2949 implementing = tree.bounds.tail;
2950 } else {
2951 extending = null;
2952 implementing = tree.bounds;
2953 }
2954 JCClassDecl cd = make.at(tree.pos).ClassDef(
2955 make.Modifiers(PUBLIC | ABSTRACT),
2956 tree.name, List.<JCTypeParameter>nil(),
2957 extending, implementing, List.<JCTree>nil());
2959 ClassSymbol c = (ClassSymbol)a.getUpperBound().tsym;
2960 Assert.check((c.flags() & COMPOUND) != 0);
2961 cd.sym = c;
2962 c.sourcefile = env.toplevel.sourcefile;
2964 // ... and attribute the bound class
2965 c.flags_field |= UNATTRIBUTED;
2966 Env<AttrContext> cenv = enter.classEnv(cd, env);
2967 enter.typeEnvs.put(c, cenv);
2968 }
2969 }
2972 public void visitWildcard(JCWildcard tree) {
2973 //- System.err.println("visitWildcard("+tree+");");//DEBUG
2974 Type type = (tree.kind.kind == BoundKind.UNBOUND)
2975 ? syms.objectType
2976 : attribType(tree.inner, env);
2977 result = check(tree, new WildcardType(chk.checkRefType(tree.pos(), type),
2978 tree.kind.kind,
2979 syms.boundClass),
2980 TYP, pkind, pt);
2981 }
2983 public void visitAnnotation(JCAnnotation tree) {
2984 log.error(tree.pos(), "annotation.not.valid.for.type", pt);
2985 result = tree.type = syms.errType;
2986 }
2988 public void visitErroneous(JCErroneous tree) {
2989 if (tree.errs != null)
2990 for (JCTree err : tree.errs)
2991 attribTree(err, env, ERR, pt);
2992 result = tree.type = syms.errType;
2993 }
2995 /** Default visitor method for all other trees.
2996 */
2997 public void visitTree(JCTree tree) {
2998 throw new AssertionError();
2999 }
3001 /** Main method: attribute class definition associated with given class symbol.
3002 * reporting completion failures at the given position.
3003 * @param pos The source position at which completion errors are to be
3004 * reported.
3005 * @param c The class symbol whose definition will be attributed.
3006 */
3007 public void attribClass(DiagnosticPosition pos, ClassSymbol c) {
3008 try {
3009 annotate.flush();
3010 attribClass(c);
3011 } catch (CompletionFailure ex) {
3012 chk.completionError(pos, ex);
3013 }
3014 }
3016 /** Attribute class definition associated with given class symbol.
3017 * @param c The class symbol whose definition will be attributed.
3018 */
3019 void attribClass(ClassSymbol c) throws CompletionFailure {
3020 if (c.type.tag == ERROR) return;
3022 // Check for cycles in the inheritance graph, which can arise from
3023 // ill-formed class files.
3024 chk.checkNonCyclic(null, c.type);
3026 Type st = types.supertype(c.type);
3027 if ((c.flags_field & Flags.COMPOUND) == 0) {
3028 // First, attribute superclass.
3029 if (st.tag == CLASS)
3030 attribClass((ClassSymbol)st.tsym);
3032 // Next attribute owner, if it is a class.
3033 if (c.owner.kind == TYP && c.owner.type.tag == CLASS)
3034 attribClass((ClassSymbol)c.owner);
3035 }
3037 // The previous operations might have attributed the current class
3038 // if there was a cycle. So we test first whether the class is still
3039 // UNATTRIBUTED.
3040 if ((c.flags_field & UNATTRIBUTED) != 0) {
3041 c.flags_field &= ~UNATTRIBUTED;
3043 // Get environment current at the point of class definition.
3044 Env<AttrContext> env = enter.typeEnvs.get(c);
3046 // The info.lint field in the envs stored in enter.typeEnvs is deliberately uninitialized,
3047 // because the annotations were not available at the time the env was created. Therefore,
3048 // we look up the environment chain for the first enclosing environment for which the
3049 // lint value is set. Typically, this is the parent env, but might be further if there
3050 // are any envs created as a result of TypeParameter nodes.
3051 Env<AttrContext> lintEnv = env;
3052 while (lintEnv.info.lint == null)
3053 lintEnv = lintEnv.next;
3055 // Having found the enclosing lint value, we can initialize the lint value for this class
3056 env.info.lint = lintEnv.info.lint.augment(c.attributes_field, c.flags());
3058 Lint prevLint = chk.setLint(env.info.lint);
3059 JavaFileObject prev = log.useSource(c.sourcefile);
3061 try {
3062 // java.lang.Enum may not be subclassed by a non-enum
3063 if (st.tsym == syms.enumSym &&
3064 ((c.flags_field & (Flags.ENUM|Flags.COMPOUND)) == 0))
3065 log.error(env.tree.pos(), "enum.no.subclassing");
3067 // Enums may not be extended by source-level classes
3068 if (st.tsym != null &&
3069 ((st.tsym.flags_field & Flags.ENUM) != 0) &&
3070 ((c.flags_field & (Flags.ENUM | Flags.COMPOUND)) == 0) &&
3071 !target.compilerBootstrap(c)) {
3072 log.error(env.tree.pos(), "enum.types.not.extensible");
3073 }
3074 attribClassBody(env, c);
3076 chk.checkDeprecatedAnnotation(env.tree.pos(), c);
3077 } finally {
3078 log.useSource(prev);
3079 chk.setLint(prevLint);
3080 }
3082 }
3083 }
3085 public void visitImport(JCImport tree) {
3086 // nothing to do
3087 }
3089 /** Finish the attribution of a class. */
3090 private void attribClassBody(Env<AttrContext> env, ClassSymbol c) {
3091 JCClassDecl tree = (JCClassDecl)env.tree;
3092 Assert.check(c == tree.sym);
3094 // Validate annotations
3095 chk.validateAnnotations(tree.mods.annotations, c);
3097 // Validate type parameters, supertype and interfaces.
3098 attribBounds(tree.typarams);
3099 if (!c.isAnonymous()) {
3100 //already checked if anonymous
3101 chk.validate(tree.typarams, env);
3102 chk.validate(tree.extending, env);
3103 chk.validate(tree.implementing, env);
3104 }
3106 // If this is a non-abstract class, check that it has no abstract
3107 // methods or unimplemented methods of an implemented interface.
3108 if ((c.flags() & (ABSTRACT | INTERFACE)) == 0) {
3109 if (!relax)
3110 chk.checkAllDefined(tree.pos(), c);
3111 }
3113 if ((c.flags() & ANNOTATION) != 0) {
3114 if (tree.implementing.nonEmpty())
3115 log.error(tree.implementing.head.pos(),
3116 "cant.extend.intf.annotation");
3117 if (tree.typarams.nonEmpty())
3118 log.error(tree.typarams.head.pos(),
3119 "intf.annotation.cant.have.type.params");
3120 } else {
3121 // Check that all extended classes and interfaces
3122 // are compatible (i.e. no two define methods with same arguments
3123 // yet different return types). (JLS 8.4.6.3)
3124 chk.checkCompatibleSupertypes(tree.pos(), c.type);
3125 }
3127 // Check that class does not import the same parameterized interface
3128 // with two different argument lists.
3129 chk.checkClassBounds(tree.pos(), c.type);
3131 tree.type = c.type;
3133 for (List<JCTypeParameter> l = tree.typarams;
3134 l.nonEmpty(); l = l.tail) {
3135 Assert.checkNonNull(env.info.scope.lookup(l.head.name).scope);
3136 }
3138 // Check that a generic class doesn't extend Throwable
3139 if (!c.type.allparams().isEmpty() && types.isSubtype(c.type, syms.throwableType))
3140 log.error(tree.extending.pos(), "generic.throwable");
3142 // Check that all methods which implement some
3143 // method conform to the method they implement.
3144 chk.checkImplementations(tree);
3146 for (List<JCTree> l = tree.defs; l.nonEmpty(); l = l.tail) {
3147 // Attribute declaration
3148 attribStat(l.head, env);
3149 // Check that declarations in inner classes are not static (JLS 8.1.2)
3150 // Make an exception for static constants.
3151 if (c.owner.kind != PCK &&
3152 ((c.flags() & STATIC) == 0 || c.name == names.empty) &&
3153 (TreeInfo.flags(l.head) & (STATIC | INTERFACE)) != 0) {
3154 Symbol sym = null;
3155 if (l.head.getTag() == JCTree.VARDEF) sym = ((JCVariableDecl) l.head).sym;
3156 if (sym == null ||
3157 sym.kind != VAR ||
3158 ((VarSymbol) sym).getConstValue() == null)
3159 log.error(l.head.pos(), "icls.cant.have.static.decl", sym.location());
3160 }
3161 }
3163 // Check for cycles among non-initial constructors.
3164 chk.checkCyclicConstructors(tree);
3166 // Check for cycles among annotation elements.
3167 chk.checkNonCyclicElements(tree);
3169 // Check for proper use of serialVersionUID
3170 if (env.info.lint.isEnabled(LintCategory.SERIAL) &&
3171 isSerializable(c) &&
3172 (c.flags() & Flags.ENUM) == 0 &&
3173 (c.flags() & ABSTRACT) == 0) {
3174 checkSerialVersionUID(tree, c);
3175 }
3176 }
3177 // where
3178 /** check if a class is a subtype of Serializable, if that is available. */
3179 private boolean isSerializable(ClassSymbol c) {
3180 try {
3181 syms.serializableType.complete();
3182 }
3183 catch (CompletionFailure e) {
3184 return false;
3185 }
3186 return types.isSubtype(c.type, syms.serializableType);
3187 }
3189 /** Check that an appropriate serialVersionUID member is defined. */
3190 private void checkSerialVersionUID(JCClassDecl tree, ClassSymbol c) {
3192 // check for presence of serialVersionUID
3193 Scope.Entry e = c.members().lookup(names.serialVersionUID);
3194 while (e.scope != null && e.sym.kind != VAR) e = e.next();
3195 if (e.scope == null) {
3196 log.warning(LintCategory.SERIAL,
3197 tree.pos(), "missing.SVUID", c);
3198 return;
3199 }
3201 // check that it is static final
3202 VarSymbol svuid = (VarSymbol)e.sym;
3203 if ((svuid.flags() & (STATIC | FINAL)) !=
3204 (STATIC | FINAL))
3205 log.warning(LintCategory.SERIAL,
3206 TreeInfo.diagnosticPositionFor(svuid, tree), "improper.SVUID", c);
3208 // check that it is long
3209 else if (svuid.type.tag != TypeTags.LONG)
3210 log.warning(LintCategory.SERIAL,
3211 TreeInfo.diagnosticPositionFor(svuid, tree), "long.SVUID", c);
3213 // check constant
3214 else if (svuid.getConstValue() == null)
3215 log.warning(LintCategory.SERIAL,
3216 TreeInfo.diagnosticPositionFor(svuid, tree), "constant.SVUID", c);
3217 }
3219 private Type capture(Type type) {
3220 return types.capture(type);
3221 }
3223 // <editor-fold desc="post-attribution visitor">
3225 /**
3226 * Handle missing types/symbols in an AST. This routine is useful when
3227 * the compiler has encountered some errors (which might have ended up
3228 * terminating attribution abruptly); if the compiler is used in fail-over
3229 * mode (e.g. by an IDE) and the AST contains semantic errors, this routine
3230 * prevents NPE to be progagated during subsequent compilation steps.
3231 */
3232 public void postAttr(Env<AttrContext> env) {
3233 new PostAttrAnalyzer().scan(env.tree);
3234 }
3236 class PostAttrAnalyzer extends TreeScanner {
3238 private void initTypeIfNeeded(JCTree that) {
3239 if (that.type == null) {
3240 that.type = syms.unknownType;
3241 }
3242 }
3244 @Override
3245 public void scan(JCTree tree) {
3246 if (tree == null) return;
3247 if (tree instanceof JCExpression) {
3248 initTypeIfNeeded(tree);
3249 }
3250 super.scan(tree);
3251 }
3253 @Override
3254 public void visitIdent(JCIdent that) {
3255 if (that.sym == null) {
3256 that.sym = syms.unknownSymbol;
3257 }
3258 }
3260 @Override
3261 public void visitSelect(JCFieldAccess that) {
3262 if (that.sym == null) {
3263 that.sym = syms.unknownSymbol;
3264 }
3265 super.visitSelect(that);
3266 }
3268 @Override
3269 public void visitClassDef(JCClassDecl that) {
3270 initTypeIfNeeded(that);
3271 if (that.sym == null) {
3272 that.sym = new ClassSymbol(0, that.name, that.type, syms.noSymbol);
3273 }
3274 super.visitClassDef(that);
3275 }
3277 @Override
3278 public void visitMethodDef(JCMethodDecl that) {
3279 initTypeIfNeeded(that);
3280 if (that.sym == null) {
3281 that.sym = new MethodSymbol(0, that.name, that.type, syms.noSymbol);
3282 }
3283 super.visitMethodDef(that);
3284 }
3286 @Override
3287 public void visitVarDef(JCVariableDecl that) {
3288 initTypeIfNeeded(that);
3289 if (that.sym == null) {
3290 that.sym = new VarSymbol(0, that.name, that.type, syms.noSymbol);
3291 that.sym.adr = 0;
3292 }
3293 super.visitVarDef(that);
3294 }
3296 @Override
3297 public void visitNewClass(JCNewClass that) {
3298 if (that.constructor == null) {
3299 that.constructor = new MethodSymbol(0, names.init, syms.unknownType, syms.noSymbol);
3300 }
3301 if (that.constructorType == null) {
3302 that.constructorType = syms.unknownType;
3303 }
3304 super.visitNewClass(that);
3305 }
3307 @Override
3308 public void visitBinary(JCBinary that) {
3309 if (that.operator == null)
3310 that.operator = new OperatorSymbol(names.empty, syms.unknownType, -1, syms.noSymbol);
3311 super.visitBinary(that);
3312 }
3314 @Override
3315 public void visitUnary(JCUnary that) {
3316 if (that.operator == null)
3317 that.operator = new OperatorSymbol(names.empty, syms.unknownType, -1, syms.noSymbol);
3318 super.visitUnary(that);
3319 }
3320 }
3321 // </editor-fold>
3322 }