1 /*
2 * Copyright (c) 1999, 2009, 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 */
25
26 package com.sun.tools.javac.comp;
27
28 import java.util.*;
29 import java.util.Set;
30 import javax.lang.model.element.ElementKind;
31 import javax.tools.JavaFileObject;
32
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;
39
40 import com.sun.tools.javac.jvm.Target;
41 import com.sun.tools.javac.code.Symbol.*;
42 import com.sun.tools.javac.tree.JCTree.*;
43 import com.sun.tools.javac.code.Type.*;
44
45 import com.sun.source.tree.IdentifierTree;
46 import com.sun.source.tree.MemberSelectTree;
47 import com.sun.source.tree.TreeVisitor;
48 import com.sun.source.util.SimpleTreeVisitor;
49
50 import static com.sun.tools.javac.code.Flags.*;
51 import static com.sun.tools.javac.code.Kinds.*;
52 import static com.sun.tools.javac.code.TypeTags.*;
53
54 /** This is the main context-dependent analysis phase in GJC. It
55 * encompasses name resolution, type checking and constant folding as
56 * subtasks. Some subtasks involve auxiliary classes.
57 * @see Check
58 * @see Resolve
59 * @see ConstFold
60 * @see Infer
61 *
62 * <p><b>This is NOT part of any supported API.
63 * If you write code that depends on this, you do so at your own risk.
64 * This code and its internal interfaces are subject to change or
65 * deletion without notice.</b>
66 */
67 public class Attr extends JCTree.Visitor {
68 protected static final Context.Key<Attr> attrKey =
69 new Context.Key<Attr>();
70
71 final Names names;
72 final Log log;
73 final Symtab syms;
74 final Resolve rs;
75 final Infer infer;
76 final Check chk;
77 final MemberEnter memberEnter;
78 final TreeMaker make;
79 final ConstFold cfolder;
80 final Enter enter;
81 final Target target;
82 final Types types;
83 final JCDiagnostic.Factory diags;
84 final Annotate annotate;
85
86 public static Attr instance(Context context) {
87 Attr instance = context.get(attrKey);
88 if (instance == null)
89 instance = new Attr(context);
90 return instance;
91 }
92
93 protected Attr(Context context) {
94 context.put(attrKey, this);
95
96 names = Names.instance(context);
97 log = Log.instance(context);
98 syms = Symtab.instance(context);
99 rs = Resolve.instance(context);
100 chk = Check.instance(context);
101 memberEnter = MemberEnter.instance(context);
102 make = TreeMaker.instance(context);
103 enter = Enter.instance(context);
104 infer = Infer.instance(context);
105 cfolder = ConstFold.instance(context);
106 target = Target.instance(context);
107 types = Types.instance(context);
108 diags = JCDiagnostic.Factory.instance(context);
109 annotate = Annotate.instance(context);
110
111 Options options = Options.instance(context);
112
113 Source source = Source.instance(context);
114 allowGenerics = source.allowGenerics();
115 allowVarargs = source.allowVarargs();
116 allowEnums = source.allowEnums();
117 allowBoxing = source.allowBoxing();
118 allowCovariantReturns = source.allowCovariantReturns();
119 allowAnonOuterThis = source.allowAnonOuterThis();
120 allowStringsInSwitch = source.allowStringsInSwitch();
121 sourceName = source.name;
122 relax = (options.get("-retrofit") != null ||
123 options.get("-relax") != null);
124 useBeforeDeclarationWarning = options.get("useBeforeDeclarationWarning") != null;
125 allowInvokedynamic = options.get("invokedynamic") != null;
126 enableSunApiLintControl = options.get("enableSunApiLintControl") != null;
127 }
128
129 /** Switch: relax some constraints for retrofit mode.
130 */
131 boolean relax;
132
133 /** Switch: support generics?
134 */
135 boolean allowGenerics;
136
137 /** Switch: allow variable-arity methods.
138 */
139 boolean allowVarargs;
140
141 /** Switch: support enums?
142 */
143 boolean allowEnums;
144
145 /** Switch: support boxing and unboxing?
146 */
147 boolean allowBoxing;
148
149 /** Switch: support covariant result types?
150 */
151 boolean allowCovariantReturns;
152
153 /** Switch: allow references to surrounding object from anonymous
154 * objects during constructor call?
155 */
156 boolean allowAnonOuterThis;
157
158 /** Switch: allow invokedynamic syntax
159 */
160 boolean allowInvokedynamic;
161
162 /**
163 * Switch: warn about use of variable before declaration?
164 * RFE: 6425594
165 */
166 boolean useBeforeDeclarationWarning;
167
168 /**
169 * Switch: allow lint infrastructure to control proprietary
170 * API warnings.
171 */
172 boolean enableSunApiLintControl;
173
174 /**
175 * Switch: allow strings in switch?
176 */
177 boolean allowStringsInSwitch;
178
179 /**
180 * Switch: name of source level; used for error reporting.
181 */
182 String sourceName;
183
184 /** Check kind and type of given tree against protokind and prototype.
185 * If check succeeds, store type in tree and return it.
186 * If check fails, store errType in tree and return it.
187 * No checks are performed if the prototype is a method type.
188 * It is not necessary in this case since we know that kind and type
189 * are correct.
190 *
191 * @param tree The tree whose kind and type is checked
192 * @param owntype The computed type of the tree
193 * @param ownkind The computed kind of the tree
194 * @param pkind The expected kind (or: protokind) of the tree
195 * @param pt The expected type (or: prototype) of the tree
196 */
197 Type check(JCTree tree, Type owntype, int ownkind, int pkind, Type pt) {
198 if (owntype.tag != ERROR && pt.tag != METHOD && pt.tag != FORALL) {
199 if ((ownkind & ~pkind) == 0) {
200 owntype = chk.checkType(tree.pos(), owntype, pt, errKey);
201 } else {
202 log.error(tree.pos(), "unexpected.type",
203 kindNames(pkind),
204 kindName(ownkind));
205 owntype = types.createErrorType(owntype);
206 }
207 }
208 tree.type = owntype;
209 return owntype;
210 }
211
212 /** Is given blank final variable assignable, i.e. in a scope where it
213 * may be assigned to even though it is final?
214 * @param v The blank final variable.
215 * @param env The current environment.
216 */
217 boolean isAssignableAsBlankFinal(VarSymbol v, Env<AttrContext> env) {
218 Symbol owner = env.info.scope.owner;
219 // owner refers to the innermost variable, method or
220 // initializer block declaration at this point.
221 return
222 v.owner == owner
223 ||
224 ((owner.name == names.init || // i.e. we are in a constructor
225 owner.kind == VAR || // i.e. we are in a variable initializer
226 (owner.flags() & BLOCK) != 0) // i.e. we are in an initializer block
227 &&
228 v.owner == owner.owner
229 &&
230 ((v.flags() & STATIC) != 0) == Resolve.isStatic(env));
231 }
232
233 /** Check that variable can be assigned to.
234 * @param pos The current source code position.
235 * @param v The assigned varaible
236 * @param base If the variable is referred to in a Select, the part
237 * to the left of the `.', null otherwise.
238 * @param env The current environment.
239 */
240 void checkAssignable(DiagnosticPosition pos, VarSymbol v, JCTree base, Env<AttrContext> env) {
241 if ((v.flags() & FINAL) != 0 &&
242 ((v.flags() & HASINIT) != 0
243 ||
244 !((base == null ||
245 (base.getTag() == JCTree.IDENT && TreeInfo.name(base) == names._this)) &&
246 isAssignableAsBlankFinal(v, env)))) {
247 if (v.isResourceVariable()) { //ARM resource
248 log.error(pos, "arm.resource.may.not.be.assigned", v);
249 } else {
250 log.error(pos, "cant.assign.val.to.final.var", v);
251 }
252 }
253 }
254
255 /** Does tree represent a static reference to an identifier?
256 * It is assumed that tree is either a SELECT or an IDENT.
257 * We have to weed out selects from non-type names here.
258 * @param tree The candidate tree.
259 */
260 boolean isStaticReference(JCTree tree) {
261 if (tree.getTag() == JCTree.SELECT) {
262 Symbol lsym = TreeInfo.symbol(((JCFieldAccess) tree).selected);
263 if (lsym == null || lsym.kind != TYP) {
264 return false;
265 }
266 }
267 return true;
268 }
269
270 /** Is this symbol a type?
271 */
272 static boolean isType(Symbol sym) {
273 return sym != null && sym.kind == TYP;
274 }
275
276 /** The current `this' symbol.
277 * @param env The current environment.
278 */
279 Symbol thisSym(DiagnosticPosition pos, Env<AttrContext> env) {
280 return rs.resolveSelf(pos, env, env.enclClass.sym, names._this);
281 }
282
283 /** Attribute a parsed identifier.
284 * @param tree Parsed identifier name
285 * @param topLevel The toplevel to use
286 */
287 public Symbol attribIdent(JCTree tree, JCCompilationUnit topLevel) {
288 Env<AttrContext> localEnv = enter.topLevelEnv(topLevel);
289 localEnv.enclClass = make.ClassDef(make.Modifiers(0),
290 syms.errSymbol.name,
291 null, null, null, null);
292 localEnv.enclClass.sym = syms.errSymbol;
293 return tree.accept(identAttributer, localEnv);
294 }
295 // where
296 private TreeVisitor<Symbol,Env<AttrContext>> identAttributer = new IdentAttributer();
297 private class IdentAttributer extends SimpleTreeVisitor<Symbol,Env<AttrContext>> {
298 @Override
299 public Symbol visitMemberSelect(MemberSelectTree node, Env<AttrContext> env) {
300 Symbol site = visit(node.getExpression(), env);
301 if (site.kind == ERR)
302 return site;
303 Name name = (Name)node.getIdentifier();
304 if (site.kind == PCK) {
305 env.toplevel.packge = (PackageSymbol)site;
306 return rs.findIdentInPackage(env, (TypeSymbol)site, name, TYP | PCK);
307 } else {
308 env.enclClass.sym = (ClassSymbol)site;
309 return rs.findMemberType(env, site.asType(), name, (TypeSymbol)site);
310 }
311 }
312
313 @Override
314 public Symbol visitIdentifier(IdentifierTree node, Env<AttrContext> env) {
315 return rs.findIdent(env, (Name)node.getName(), TYP | PCK);
316 }
317 }
318
319 public Type coerce(Type etype, Type ttype) {
320 return cfolder.coerce(etype, ttype);
321 }
322
323 public Type attribType(JCTree node, TypeSymbol sym) {
324 Env<AttrContext> env = enter.typeEnvs.get(sym);
325 Env<AttrContext> localEnv = env.dup(node, env.info.dup());
326 return attribTree(node, localEnv, Kinds.TYP, Type.noType);
327 }
328
329 public Env<AttrContext> attribExprToTree(JCTree expr, Env<AttrContext> env, JCTree tree) {
330 breakTree = tree;
331 JavaFileObject prev = log.useSource(env.toplevel.sourcefile);
332 try {
333 attribExpr(expr, env);
334 } catch (BreakAttr b) {
335 return b.env;
336 } finally {
337 breakTree = null;
338 log.useSource(prev);
339 }
340 return env;
341 }
342
343 public Env<AttrContext> attribStatToTree(JCTree stmt, Env<AttrContext> env, JCTree tree) {
344 breakTree = tree;
345 JavaFileObject prev = log.useSource(env.toplevel.sourcefile);
346 try {
347 attribStat(stmt, env);
348 } catch (BreakAttr b) {
349 return b.env;
350 } finally {
351 breakTree = null;
352 log.useSource(prev);
353 }
354 return env;
355 }
356
357 private JCTree breakTree = null;
358
359 private static class BreakAttr extends RuntimeException {
360 static final long serialVersionUID = -6924771130405446405L;
361 private Env<AttrContext> env;
362 private BreakAttr(Env<AttrContext> env) {
363 this.env = env;
364 }
365 }
366
367
368 /* ************************************************************************
369 * Visitor methods
370 *************************************************************************/
371
372 /** Visitor argument: the current environment.
373 */
374 Env<AttrContext> env;
375
376 /** Visitor argument: the currently expected proto-kind.
377 */
378 int pkind;
379
380 /** Visitor argument: the currently expected proto-type.
381 */
382 Type pt;
383
384 /** Visitor argument: the error key to be generated when a type error occurs
385 */
386 String errKey;
387
388 /** Visitor result: the computed type.
389 */
390 Type result;
391
392 /** Visitor method: attribute a tree, catching any completion failure
393 * exceptions. Return the tree's type.
394 *
395 * @param tree The tree to be visited.
396 * @param env The environment visitor argument.
397 * @param pkind The protokind visitor argument.
398 * @param pt The prototype visitor argument.
399 */
400 Type attribTree(JCTree tree, Env<AttrContext> env, int pkind, Type pt) {
401 return attribTree(tree, env, pkind, pt, "incompatible.types");
402 }
403
404 Type attribTree(JCTree tree, Env<AttrContext> env, int pkind, Type pt, String errKey) {
405 Env<AttrContext> prevEnv = this.env;
406 int prevPkind = this.pkind;
407 Type prevPt = this.pt;
408 String prevErrKey = this.errKey;
409 try {
410 this.env = env;
411 this.pkind = pkind;
412 this.pt = pt;
413 this.errKey = errKey;
414 tree.accept(this);
415 if (tree == breakTree)
416 throw new BreakAttr(env);
417 return result;
418 } catch (CompletionFailure ex) {
419 tree.type = syms.errType;
420 return chk.completionError(tree.pos(), ex);
421 } finally {
422 this.env = prevEnv;
423 this.pkind = prevPkind;
424 this.pt = prevPt;
425 this.errKey = prevErrKey;
426 }
427 }
428
429 /** Derived visitor method: attribute an expression tree.
430 */
431 public Type attribExpr(JCTree tree, Env<AttrContext> env, Type pt) {
432 return attribTree(tree, env, VAL, pt.tag != ERROR ? pt : Type.noType);
433 }
434
435 public Type attribExpr(JCTree tree, Env<AttrContext> env, Type pt, String key) {
436 return attribTree(tree, env, VAL, pt.tag != ERROR ? pt : Type.noType, key);
437 }
438
439 /** Derived visitor method: attribute an expression tree with
440 * no constraints on the computed type.
441 */
442 Type attribExpr(JCTree tree, Env<AttrContext> env) {
443 return attribTree(tree, env, VAL, Type.noType);
444 }
445
446 /** Derived visitor method: attribute a type tree.
447 */
448 Type attribType(JCTree tree, Env<AttrContext> env) {
449 Type result = attribType(tree, env, Type.noType);
450 return result;
451 }
452
453 /** Derived visitor method: attribute a type tree.
454 */
455 Type attribType(JCTree tree, Env<AttrContext> env, Type pt) {
456 Type result = attribTree(tree, env, TYP, pt);
457 return result;
458 }
459
460 /** Derived visitor method: attribute a statement or definition tree.
461 */
462 public Type attribStat(JCTree tree, Env<AttrContext> env) {
463 return attribTree(tree, env, NIL, Type.noType);
464 }
465
466 /** Attribute a list of expressions, returning a list of types.
467 */
468 List<Type> attribExprs(List<JCExpression> trees, Env<AttrContext> env, Type pt) {
469 ListBuffer<Type> ts = new ListBuffer<Type>();
470 for (List<JCExpression> l = trees; l.nonEmpty(); l = l.tail)
471 ts.append(attribExpr(l.head, env, pt));
472 return ts.toList();
473 }
474
475 /** Attribute a list of statements, returning nothing.
476 */
477 <T extends JCTree> void attribStats(List<T> trees, Env<AttrContext> env) {
478 for (List<T> l = trees; l.nonEmpty(); l = l.tail)
479 attribStat(l.head, env);
480 }
481
482 /** Attribute the arguments in a method call, returning a list of types.
483 */
484 List<Type> attribArgs(List<JCExpression> trees, Env<AttrContext> env) {
485 ListBuffer<Type> argtypes = new ListBuffer<Type>();
486 for (List<JCExpression> l = trees; l.nonEmpty(); l = l.tail)
487 argtypes.append(chk.checkNonVoid(
488 l.head.pos(), types.upperBound(attribTree(l.head, env, VAL, Infer.anyPoly))));
489 return argtypes.toList();
490 }
491
492 /** Attribute a type argument list, returning a list of types.
493 * Caller is responsible for calling checkRefTypes.
494 */
495 List<Type> attribAnyTypes(List<JCExpression> trees, Env<AttrContext> env) {
496 ListBuffer<Type> argtypes = new ListBuffer<Type>();
497 for (List<JCExpression> l = trees; l.nonEmpty(); l = l.tail)
498 argtypes.append(attribType(l.head, env));
499 return argtypes.toList();
500 }
501
502 /** Attribute a type argument list, returning a list of types.
503 * Check that all the types are references.
504 */
505 List<Type> attribTypes(List<JCExpression> trees, Env<AttrContext> env) {
506 List<Type> types = attribAnyTypes(trees, env);
507 return chk.checkRefTypes(trees, types);
508 }
509
510 /**
511 * Attribute type variables (of generic classes or methods).
512 * Compound types are attributed later in attribBounds.
513 * @param typarams the type variables to enter
514 * @param env the current environment
515 */
516 void attribTypeVariables(List<JCTypeParameter> typarams, Env<AttrContext> env) {
517 for (JCTypeParameter tvar : typarams) {
518 TypeVar a = (TypeVar)tvar.type;
519 a.tsym.flags_field |= UNATTRIBUTED;
520 a.bound = Type.noType;
521 if (!tvar.bounds.isEmpty()) {
522 List<Type> bounds = List.of(attribType(tvar.bounds.head, env));
523 for (JCExpression bound : tvar.bounds.tail)
524 bounds = bounds.prepend(attribType(bound, env));
525 types.setBounds(a, bounds.reverse());
526 } else {
527 // if no bounds are given, assume a single bound of
528 // java.lang.Object.
529 types.setBounds(a, List.of(syms.objectType));
530 }
531 a.tsym.flags_field &= ~UNATTRIBUTED;
532 }
533 for (JCTypeParameter tvar : typarams)
534 chk.checkNonCyclic(tvar.pos(), (TypeVar)tvar.type);
535 attribStats(typarams, env);
536 }
537
538 void attribBounds(List<JCTypeParameter> typarams) {
539 for (JCTypeParameter typaram : typarams) {
540 Type bound = typaram.type.getUpperBound();
541 if (bound != null && bound.tsym instanceof ClassSymbol) {
542 ClassSymbol c = (ClassSymbol)bound.tsym;
543 if ((c.flags_field & COMPOUND) != 0) {
544 assert (c.flags_field & UNATTRIBUTED) != 0 : c;
545 attribClass(typaram.pos(), c);
546 }
547 }
548 }
549 }
550
551 /**
552 * Attribute the type references in a list of annotations.
553 */
554 void attribAnnotationTypes(List<JCAnnotation> annotations,
555 Env<AttrContext> env) {
556 for (List<JCAnnotation> al = annotations; al.nonEmpty(); al = al.tail) {
557 JCAnnotation a = al.head;
558 attribType(a.annotationType, env);
559 }
560 }
561
562 /** Attribute type reference in an `extends' or `implements' clause.
563 * Supertypes of anonymous inner classes are usually already attributed.
564 *
565 * @param tree The tree making up the type reference.
566 * @param env The environment current at the reference.
567 * @param classExpected true if only a class is expected here.
568 * @param interfaceExpected true if only an interface is expected here.
569 */
570 Type attribBase(JCTree tree,
571 Env<AttrContext> env,
572 boolean classExpected,
573 boolean interfaceExpected,
574 boolean checkExtensible) {
575 Type t = tree.type != null ?
576 tree.type :
577 attribType(tree, env);
578 return checkBase(t, tree, env, classExpected, interfaceExpected, checkExtensible);
579 }
580 Type checkBase(Type t,
581 JCTree tree,
582 Env<AttrContext> env,
583 boolean classExpected,
584 boolean interfaceExpected,
585 boolean checkExtensible) {
586 if (t.tag == TYPEVAR && !classExpected && !interfaceExpected) {
587 // check that type variable is already visible
588 if (t.getUpperBound() == null) {
589 log.error(tree.pos(), "illegal.forward.ref");
590 return types.createErrorType(t);
591 }
592 } else {
593 t = chk.checkClassType(tree.pos(), t, checkExtensible|!allowGenerics);
594 }
595 if (interfaceExpected && (t.tsym.flags() & INTERFACE) == 0) {
596 log.error(tree.pos(), "intf.expected.here");
597 // return errType is necessary since otherwise there might
598 // be undetected cycles which cause attribution to loop
599 return types.createErrorType(t);
600 } else if (checkExtensible &&
601 classExpected &&
602 (t.tsym.flags() & INTERFACE) != 0) {
603 log.error(tree.pos(), "no.intf.expected.here");
604 return types.createErrorType(t);
605 }
606 if (checkExtensible &&
607 ((t.tsym.flags() & FINAL) != 0)) {
608 log.error(tree.pos(),
609 "cant.inherit.from.final", t.tsym);
610 }
611 chk.checkNonCyclic(tree.pos(), t);
612 return t;
613 }
614
615 public void visitClassDef(JCClassDecl tree) {
616 // Local classes have not been entered yet, so we need to do it now:
617 if ((env.info.scope.owner.kind & (VAR | MTH)) != 0)
618 enter.classEnter(tree, env);
619
620 ClassSymbol c = tree.sym;
621 if (c == null) {
622 // exit in case something drastic went wrong during enter.
623 result = null;
624 } else {
625 // make sure class has been completed:
626 c.complete();
627
628 // If this class appears as an anonymous class
629 // in a superclass constructor call where
630 // no explicit outer instance is given,
631 // disable implicit outer instance from being passed.
632 // (This would be an illegal access to "this before super").
633 if (env.info.isSelfCall &&
634 env.tree.getTag() == JCTree.NEWCLASS &&
635 ((JCNewClass) env.tree).encl == null)
636 {
637 c.flags_field |= NOOUTERTHIS;
638 }
639 attribClass(tree.pos(), c);
640 result = tree.type = c.type;
641 }
642 }
643
644 public void visitMethodDef(JCMethodDecl tree) {
645 MethodSymbol m = tree.sym;
646
647 Lint lint = env.info.lint.augment(m.attributes_field, m.flags());
648 Lint prevLint = chk.setLint(lint);
649 try {
650 chk.checkDeprecatedAnnotation(tree.pos(), m);
651
652 attribBounds(tree.typarams);
653
654 // If we override any other methods, check that we do so properly.
655 // JLS ???
656 chk.checkOverride(tree, m);
657
658 // Create a new environment with local scope
659 // for attributing the method.
660 Env<AttrContext> localEnv = memberEnter.methodEnv(tree, env);
661
662 localEnv.info.lint = lint;
663
664 // Enter all type parameters into the local method scope.
665 for (List<JCTypeParameter> l = tree.typarams; l.nonEmpty(); l = l.tail)
666 localEnv.info.scope.enterIfAbsent(l.head.type.tsym);
667
668 ClassSymbol owner = env.enclClass.sym;
669 if ((owner.flags() & ANNOTATION) != 0 &&
670 tree.params.nonEmpty())
671 log.error(tree.params.head.pos(),
672 "intf.annotation.members.cant.have.params");
673
674 // Attribute all value parameters.
675 for (List<JCVariableDecl> l = tree.params; l.nonEmpty(); l = l.tail) {
676 attribStat(l.head, localEnv);
677 }
678
679 chk.checkVarargMethodDecl(tree);
680
681 // Check that type parameters are well-formed.
682 chk.validate(tree.typarams, localEnv);
683 if ((owner.flags() & ANNOTATION) != 0 &&
684 tree.typarams.nonEmpty())
685 log.error(tree.typarams.head.pos(),
686 "intf.annotation.members.cant.have.type.params");
687
688 // Check that result type is well-formed.
689 chk.validate(tree.restype, localEnv);
690 if ((owner.flags() & ANNOTATION) != 0)
691 chk.validateAnnotationType(tree.restype);
692
693 if ((owner.flags() & ANNOTATION) != 0)
694 chk.validateAnnotationMethod(tree.pos(), m);
695
696 // Check that all exceptions mentioned in the throws clause extend
697 // java.lang.Throwable.
698 if ((owner.flags() & ANNOTATION) != 0 && tree.thrown.nonEmpty())
699 log.error(tree.thrown.head.pos(),
700 "throws.not.allowed.in.intf.annotation");
701 for (List<JCExpression> l = tree.thrown; l.nonEmpty(); l = l.tail)
702 chk.checkType(l.head.pos(), l.head.type, syms.throwableType);
703
704 if (tree.body == null) {
705 // Empty bodies are only allowed for
706 // abstract, native, or interface methods, or for methods
707 // in a retrofit signature class.
708 if ((owner.flags() & INTERFACE) == 0 &&
709 (tree.mods.flags & (ABSTRACT | NATIVE)) == 0 &&
710 !relax)
711 log.error(tree.pos(), "missing.meth.body.or.decl.abstract");
712 if (tree.defaultValue != null) {
713 if ((owner.flags() & ANNOTATION) == 0)
714 log.error(tree.pos(),
715 "default.allowed.in.intf.annotation.member");
716 }
717 } else if ((owner.flags() & INTERFACE) != 0) {
718 log.error(tree.body.pos(), "intf.meth.cant.have.body");
719 } else if ((tree.mods.flags & ABSTRACT) != 0) {
720 log.error(tree.pos(), "abstract.meth.cant.have.body");
721 } else if ((tree.mods.flags & NATIVE) != 0) {
722 log.error(tree.pos(), "native.meth.cant.have.body");
723 } else {
724 // Add an implicit super() call unless an explicit call to
725 // super(...) or this(...) is given
726 // or we are compiling class java.lang.Object.
727 if (tree.name == names.init && owner.type != syms.objectType) {
728 JCBlock body = tree.body;
729 if (body.stats.isEmpty() ||
730 !TreeInfo.isSelfCall(body.stats.head)) {
731 body.stats = body.stats.
732 prepend(memberEnter.SuperCall(make.at(body.pos),
733 List.<Type>nil(),
734 List.<JCVariableDecl>nil(),
735 false));
736 } else if ((env.enclClass.sym.flags() & ENUM) != 0 &&
737 (tree.mods.flags & GENERATEDCONSTR) == 0 &&
738 TreeInfo.isSuperCall(body.stats.head)) {
739 // enum constructors are not allowed to call super
740 // directly, so make sure there aren't any super calls
741 // in enum constructors, except in the compiler
742 // generated one.
743 log.error(tree.body.stats.head.pos(),
744 "call.to.super.not.allowed.in.enum.ctor",
745 env.enclClass.sym);
746 }
747 }
748
749 // Attribute method body.
750 attribStat(tree.body, localEnv);
751 }
752 localEnv.info.scope.leave();
753 result = tree.type = m.type;
754 chk.validateAnnotations(tree.mods.annotations, m);
755 }
756 finally {
757 chk.setLint(prevLint);
758 }
759 }
760
761 public void visitVarDef(JCVariableDecl tree) {
762 // Local variables have not been entered yet, so we need to do it now:
763 if (env.info.scope.owner.kind == MTH) {
764 if (tree.sym != null) {
765 // parameters have already been entered
766 env.info.scope.enter(tree.sym);
767 } else {
768 memberEnter.memberEnter(tree, env);
769 annotate.flush();
770 }
771 }
772
773 VarSymbol v = tree.sym;
774 Lint lint = env.info.lint.augment(v.attributes_field, v.flags());
775 Lint prevLint = chk.setLint(lint);
776
777 // Check that the variable's declared type is well-formed.
778 chk.validate(tree.vartype, env);
779
780 try {
781 chk.checkDeprecatedAnnotation(tree.pos(), v);
782
783 if (tree.init != null) {
784 if ((v.flags_field & FINAL) != 0 && tree.init.getTag() != JCTree.NEWCLASS) {
785 // In this case, `v' is final. Ensure that it's initializer is
786 // evaluated.
787 v.getConstValue(); // ensure initializer is evaluated
788 } else {
789 // Attribute initializer in a new environment
790 // with the declared variable as owner.
791 // Check that initializer conforms to variable's declared type.
792 Env<AttrContext> initEnv = memberEnter.initEnv(tree, env);
793 initEnv.info.lint = lint;
794 // In order to catch self-references, we set the variable's
795 // declaration position to maximal possible value, effectively
796 // marking the variable as undefined.
797 initEnv.info.enclVar = v;
798 attribExpr(tree.init, initEnv, v.type);
799 }
800 }
801 result = tree.type = v.type;
802 chk.validateAnnotations(tree.mods.annotations, v);
803 }
804 finally {
805 chk.setLint(prevLint);
806 }
807 }
808
809 public void visitSkip(JCSkip tree) {
810 result = null;
811 }
812
813 public void visitBlock(JCBlock tree) {
814 if (env.info.scope.owner.kind == TYP) {
815 // Block is a static or instance initializer;
816 // let the owner of the environment be a freshly
817 // created BLOCK-method.
818 Env<AttrContext> localEnv =
819 env.dup(tree, env.info.dup(env.info.scope.dupUnshared()));
820 localEnv.info.scope.owner =
821 new MethodSymbol(tree.flags | BLOCK, names.empty, null,
822 env.info.scope.owner);
823 if ((tree.flags & STATIC) != 0) localEnv.info.staticLevel++;
824 attribStats(tree.stats, localEnv);
825 } else {
826 // Create a new local environment with a local scope.
827 Env<AttrContext> localEnv =
828 env.dup(tree, env.info.dup(env.info.scope.dup()));
829 attribStats(tree.stats, localEnv);
830 localEnv.info.scope.leave();
831 }
832 result = null;
833 }
834
835 public void visitDoLoop(JCDoWhileLoop tree) {
836 attribStat(tree.body, env.dup(tree));
837 attribExpr(tree.cond, env, syms.booleanType);
838 result = null;
839 }
840
841 public void visitWhileLoop(JCWhileLoop tree) {
842 attribExpr(tree.cond, env, syms.booleanType);
843 attribStat(tree.body, env.dup(tree));
844 result = null;
845 }
846
847 public void visitForLoop(JCForLoop tree) {
848 Env<AttrContext> loopEnv =
849 env.dup(env.tree, env.info.dup(env.info.scope.dup()));
850 attribStats(tree.init, loopEnv);
851 if (tree.cond != null) attribExpr(tree.cond, loopEnv, syms.booleanType);
852 loopEnv.tree = tree; // before, we were not in loop!
853 attribStats(tree.step, loopEnv);
854 attribStat(tree.body, loopEnv);
855 loopEnv.info.scope.leave();
856 result = null;
857 }
858
859 public void visitForeachLoop(JCEnhancedForLoop tree) {
860 Env<AttrContext> loopEnv =
861 env.dup(env.tree, env.info.dup(env.info.scope.dup()));
862 attribStat(tree.var, loopEnv);
863 Type exprType = types.upperBound(attribExpr(tree.expr, loopEnv));
864 chk.checkNonVoid(tree.pos(), exprType);
865 Type elemtype = types.elemtype(exprType); // perhaps expr is an array?
866 if (elemtype == null) {
867 // or perhaps expr implements Iterable<T>?
868 Type base = types.asSuper(exprType, syms.iterableType.tsym);
869 if (base == null) {
870 log.error(tree.expr.pos(), "foreach.not.applicable.to.type");
871 elemtype = types.createErrorType(exprType);
872 } else {
873 List<Type> iterableParams = base.allparams();
874 elemtype = iterableParams.isEmpty()
875 ? syms.objectType
876 : types.upperBound(iterableParams.head);
877 }
878 }
879 chk.checkType(tree.expr.pos(), elemtype, tree.var.sym.type);
880 loopEnv.tree = tree; // before, we were not in loop!
881 attribStat(tree.body, loopEnv);
882 loopEnv.info.scope.leave();
883 result = null;
884 }
885
886 public void visitLabelled(JCLabeledStatement tree) {
887 // Check that label is not used in an enclosing statement
888 Env<AttrContext> env1 = env;
889 while (env1 != null && env1.tree.getTag() != JCTree.CLASSDEF) {
890 if (env1.tree.getTag() == JCTree.LABELLED &&
891 ((JCLabeledStatement) env1.tree).label == tree.label) {
892 log.error(tree.pos(), "label.already.in.use",
893 tree.label);
894 break;
895 }
896 env1 = env1.next;
897 }
898
899 attribStat(tree.body, env.dup(tree));
900 result = null;
901 }
902
903 public void visitSwitch(JCSwitch tree) {
904 Type seltype = attribExpr(tree.selector, env);
905
906 Env<AttrContext> switchEnv =
907 env.dup(tree, env.info.dup(env.info.scope.dup()));
908
909 boolean enumSwitch =
910 allowEnums &&
911 (seltype.tsym.flags() & Flags.ENUM) != 0;
912 boolean stringSwitch = false;
913 if (types.isSameType(seltype, syms.stringType)) {
914 if (allowStringsInSwitch) {
915 stringSwitch = true;
916 } else {
917 log.error(tree.selector.pos(), "string.switch.not.supported.in.source", sourceName);
918 }
919 }
920 if (!enumSwitch && !stringSwitch)
921 seltype = chk.checkType(tree.selector.pos(), seltype, syms.intType);
922
923 // Attribute all cases and
924 // check that there are no duplicate case labels or default clauses.
925 Set<Object> labels = new HashSet<Object>(); // The set of case labels.
926 boolean hasDefault = false; // Is there a default label?
927 for (List<JCCase> l = tree.cases; l.nonEmpty(); l = l.tail) {
928 JCCase c = l.head;
929 Env<AttrContext> caseEnv =
930 switchEnv.dup(c, env.info.dup(switchEnv.info.scope.dup()));
931 if (c.pat != null) {
932 if (enumSwitch) {
933 Symbol sym = enumConstant(c.pat, seltype);
934 if (sym == null) {
935 log.error(c.pat.pos(), "enum.const.req");
936 } else if (!labels.add(sym)) {
937 log.error(c.pos(), "duplicate.case.label");
938 }
939 } else {
940 Type pattype = attribExpr(c.pat, switchEnv, seltype);
941 if (pattype.tag != ERROR) {
942 if (pattype.constValue() == null) {
943 log.error(c.pat.pos(),
944 (stringSwitch ? "string.const.req" : "const.expr.req"));
945 } else if (labels.contains(pattype.constValue())) {
946 log.error(c.pos(), "duplicate.case.label");
947 } else {
948 labels.add(pattype.constValue());
949 }
950 }
951 }
952 } else if (hasDefault) {
953 log.error(c.pos(), "duplicate.default.label");
954 } else {
955 hasDefault = true;
956 }
957 attribStats(c.stats, caseEnv);
958 caseEnv.info.scope.leave();
959 addVars(c.stats, switchEnv.info.scope);
960 }
961
962 switchEnv.info.scope.leave();
963 result = null;
964 }
965 // where
966 /** Add any variables defined in stats to the switch scope. */
967 private static void addVars(List<JCStatement> stats, Scope switchScope) {
968 for (;stats.nonEmpty(); stats = stats.tail) {
969 JCTree stat = stats.head;
970 if (stat.getTag() == JCTree.VARDEF)
971 switchScope.enter(((JCVariableDecl) stat).sym);
972 }
973 }
974 // where
975 /** Return the selected enumeration constant symbol, or null. */
976 private Symbol enumConstant(JCTree tree, Type enumType) {
977 if (tree.getTag() != JCTree.IDENT) {
978 log.error(tree.pos(), "enum.label.must.be.unqualified.enum");
979 return syms.errSymbol;
980 }
981 JCIdent ident = (JCIdent)tree;
982 Name name = ident.name;
983 for (Scope.Entry e = enumType.tsym.members().lookup(name);
984 e.scope != null; e = e.next()) {
985 if (e.sym.kind == VAR) {
986 Symbol s = ident.sym = e.sym;
987 ((VarSymbol)s).getConstValue(); // ensure initializer is evaluated
988 ident.type = s.type;
989 return ((s.flags_field & Flags.ENUM) == 0)
990 ? null : s;
991 }
992 }
993 return null;
994 }
995
996 public void visitSynchronized(JCSynchronized tree) {
997 chk.checkRefType(tree.pos(), attribExpr(tree.lock, env));
998 attribStat(tree.body, env);
999 result = null;
1000 }
1001
1002 public void visitTry(JCTry tree) {
1003 // Create a new local environment with a local scope.
1004 Env<AttrContext> localEnv = env.dup(tree, env.info.dup(env.info.scope.dup()));
1005 // Attribute resource declarations
1006 ListBuffer<VarSymbol> resourceVars = ListBuffer.lb();
1007 for (JCTree resource : tree.resources) {
1008 if (resource.getTag() == JCTree.VARDEF) {
1009 attribStat(resource, localEnv);
1010 chk.checkType(resource, resource.type, syms.autoCloseableType, "arm.not.applicable.to.type");
1011 VarSymbol var = (VarSymbol)TreeInfo.symbolFor(resource);
1012 var.setData(ElementKind.RESOURCE_VARIABLE);
1013 resourceVars.append(var);
1014 } else {
1015 attribExpr(resource, localEnv, syms.autoCloseableType, "arm.not.applicable.to.type");
1016 }
1017 }
1018 // Attribute body
1019 attribStat(tree.body, localEnv.dup(tree, localEnv.info.dup()));
1020
1021 //remove arm resource vars from local scope - such variables cannot be
1022 //accessed from catch/finally clauses
1023 for (VarSymbol resourceVar : resourceVars) {
1024 localEnv.info.scope.remove(resourceVar);
1025 }
1026
1027 // Attribute catch clauses
1028 for (List<JCCatch> l = tree.catchers; l.nonEmpty(); l = l.tail) {
1029 JCCatch c = l.head;
1030 Env<AttrContext> catchEnv =
1031 localEnv.dup(c, localEnv.info.dup(localEnv.info.scope.dup()));
1032 Type ctype = attribStat(c.param, catchEnv);
1033 if (TreeInfo.isMultiCatch(c)) {
1034 //check that multi-catch parameter is marked as final
1035 if ((c.param.sym.flags() & FINAL) == 0) {
1036 log.error(c.param.pos(), "multicatch.param.must.be.final", c.param.sym);
1037 }
1038 c.param.sym.flags_field = c.param.sym.flags() | DISJOINT;
1039 }
1040 if (c.param.type.tsym.kind == Kinds.VAR) {
1041 c.param.sym.setData(ElementKind.EXCEPTION_PARAMETER);
1042 }
1043 chk.checkType(c.param.vartype.pos(),
1044 chk.checkClassType(c.param.vartype.pos(), ctype),
1045 syms.throwableType);
1046 attribStat(c.body, catchEnv);
1047 catchEnv.info.scope.leave();
1048 }
1049
1050 // Attribute finalizer
1051 if (tree.finalizer != null) attribStat(tree.finalizer, localEnv);
1052
1053 localEnv.info.scope.leave();
1054 result = null;
1055 }
1056
1057 public void visitConditional(JCConditional tree) {
1058 attribExpr(tree.cond, env, syms.booleanType);
1059 attribExpr(tree.truepart, env);
1060 attribExpr(tree.falsepart, env);
1061 result = check(tree,
1062 capture(condType(tree.pos(), tree.cond.type,
1063 tree.truepart.type, tree.falsepart.type)),
1064 VAL, pkind, pt);
1065 }
1066 //where
1067 /** Compute the type of a conditional expression, after
1068 * checking that it exists. See Spec 15.25.
1069 *
1070 * @param pos The source position to be used for
1071 * error diagnostics.
1072 * @param condtype The type of the expression's condition.
1073 * @param thentype The type of the expression's then-part.
1074 * @param elsetype The type of the expression's else-part.
1075 */
1076 private Type condType(DiagnosticPosition pos,
1077 Type condtype,
1078 Type thentype,
1079 Type elsetype) {
1080 Type ctype = condType1(pos, condtype, thentype, elsetype);
1081
1082 // If condition and both arms are numeric constants,
1083 // evaluate at compile-time.
1084 return ((condtype.constValue() != null) &&
1085 (thentype.constValue() != null) &&
1086 (elsetype.constValue() != null))
1087 ? cfolder.coerce(condtype.isTrue()?thentype:elsetype, ctype)
1088 : ctype;
1089 }
1090 /** Compute the type of a conditional expression, after
1091 * checking that it exists. Does not take into
1092 * account the special case where condition and both arms
1093 * are constants.
1094 *
1095 * @param pos The source position to be used for error
1096 * diagnostics.
1097 * @param condtype The type of the expression's condition.
1098 * @param thentype The type of the expression's then-part.
1099 * @param elsetype The type of the expression's else-part.
1100 */
1101 private Type condType1(DiagnosticPosition pos, Type condtype,
1102 Type thentype, Type elsetype) {
1103 // If same type, that is the result
1104 if (types.isSameType(thentype, elsetype))
1105 return thentype.baseType();
1106
1107 Type thenUnboxed = (!allowBoxing || thentype.isPrimitive())
1108 ? thentype : types.unboxedType(thentype);
1109 Type elseUnboxed = (!allowBoxing || elsetype.isPrimitive())
1110 ? elsetype : types.unboxedType(elsetype);
1111
1112 // Otherwise, if both arms can be converted to a numeric
1113 // type, return the least numeric type that fits both arms
1114 // (i.e. return larger of the two, or return int if one
1115 // arm is short, the other is char).
1116 if (thenUnboxed.isPrimitive() && elseUnboxed.isPrimitive()) {
1117 // If one arm has an integer subrange type (i.e., byte,
1118 // short, or char), and the other is an integer constant
1119 // that fits into the subrange, return the subrange type.
1120 if (thenUnboxed.tag < INT && elseUnboxed.tag == INT &&
1121 types.isAssignable(elseUnboxed, thenUnboxed))
1122 return thenUnboxed.baseType();
1123 if (elseUnboxed.tag < INT && thenUnboxed.tag == INT &&
1124 types.isAssignable(thenUnboxed, elseUnboxed))
1125 return elseUnboxed.baseType();
1126
1127 for (int i = BYTE; i < VOID; i++) {
1128 Type candidate = syms.typeOfTag[i];
1129 if (types.isSubtype(thenUnboxed, candidate) &&
1130 types.isSubtype(elseUnboxed, candidate))
1131 return candidate;
1132 }
1133 }
1134
1135 // Those were all the cases that could result in a primitive
1136 if (allowBoxing) {
1137 if (thentype.isPrimitive())
1138 thentype = types.boxedClass(thentype).type;
1139 if (elsetype.isPrimitive())
1140 elsetype = types.boxedClass(elsetype).type;
1141 }
1142
1143 if (types.isSubtype(thentype, elsetype))
1144 return elsetype.baseType();
1145 if (types.isSubtype(elsetype, thentype))
1146 return thentype.baseType();
1147
1148 if (!allowBoxing || thentype.tag == VOID || elsetype.tag == VOID) {
1149 log.error(pos, "neither.conditional.subtype",
1150 thentype, elsetype);
1151 return thentype.baseType();
1152 }
1153
1154 // both are known to be reference types. The result is
1155 // lub(thentype,elsetype). This cannot fail, as it will
1156 // always be possible to infer "Object" if nothing better.
1157 return types.lub(thentype.baseType(), elsetype.baseType());
1158 }
1159
1160 public void visitIf(JCIf tree) {
1161 attribExpr(tree.cond, env, syms.booleanType);
1162 attribStat(tree.thenpart, env);
1163 if (tree.elsepart != null)
1164 attribStat(tree.elsepart, env);
1165 chk.checkEmptyIf(tree);
1166 result = null;
1167 }
1168
1169 public void visitExec(JCExpressionStatement tree) {
1170 attribExpr(tree.expr, env);
1171 result = null;
1172 }
1173
1174 public void visitBreak(JCBreak tree) {
1175 tree.target = findJumpTarget(tree.pos(), tree.getTag(), tree.label, env);
1176 result = null;
1177 }
1178
1179 public void visitContinue(JCContinue tree) {
1180 tree.target = findJumpTarget(tree.pos(), tree.getTag(), tree.label, env);
1181 result = null;
1182 }
1183 //where
1184 /** Return the target of a break or continue statement, if it exists,
1185 * report an error if not.
1186 * Note: The target of a labelled break or continue is the
1187 * (non-labelled) statement tree referred to by the label,
1188 * not the tree representing the labelled statement itself.
1189 *
1190 * @param pos The position to be used for error diagnostics
1191 * @param tag The tag of the jump statement. This is either
1192 * Tree.BREAK or Tree.CONTINUE.
1193 * @param label The label of the jump statement, or null if no
1194 * label is given.
1195 * @param env The environment current at the jump statement.
1196 */
1197 private JCTree findJumpTarget(DiagnosticPosition pos,
1198 int tag,
1199 Name label,
1200 Env<AttrContext> env) {
1201 // Search environments outwards from the point of jump.
1202 Env<AttrContext> env1 = env;
1203 LOOP:
1204 while (env1 != null) {
1205 switch (env1.tree.getTag()) {
1206 case JCTree.LABELLED:
1207 JCLabeledStatement labelled = (JCLabeledStatement)env1.tree;
1208 if (label == labelled.label) {
1209 // If jump is a continue, check that target is a loop.
1210 if (tag == JCTree.CONTINUE) {
1211 if (labelled.body.getTag() != JCTree.DOLOOP &&
1212 labelled.body.getTag() != JCTree.WHILELOOP &&
1213 labelled.body.getTag() != JCTree.FORLOOP &&
1214 labelled.body.getTag() != JCTree.FOREACHLOOP)
1215 log.error(pos, "not.loop.label", label);
1216 // Found labelled statement target, now go inwards
1217 // to next non-labelled tree.
1218 return TreeInfo.referencedStatement(labelled);
1219 } else {
1220 return labelled;
1221 }
1222 }
1223 break;
1224 case JCTree.DOLOOP:
1225 case JCTree.WHILELOOP:
1226 case JCTree.FORLOOP:
1227 case JCTree.FOREACHLOOP:
1228 if (label == null) return env1.tree;
1229 break;
1230 case JCTree.SWITCH:
1231 if (label == null && tag == JCTree.BREAK) return env1.tree;
1232 break;
1233 case JCTree.METHODDEF:
1234 case JCTree.CLASSDEF:
1235 break LOOP;
1236 default:
1237 }
1238 env1 = env1.next;
1239 }
1240 if (label != null)
1241 log.error(pos, "undef.label", label);
1242 else if (tag == JCTree.CONTINUE)
1243 log.error(pos, "cont.outside.loop");
1244 else
1245 log.error(pos, "break.outside.switch.loop");
1246 return null;
1247 }
1248
1249 public void visitReturn(JCReturn tree) {
1250 // Check that there is an enclosing method which is
1251 // nested within than the enclosing class.
1252 if (env.enclMethod == null ||
1253 env.enclMethod.sym.owner != env.enclClass.sym) {
1254 log.error(tree.pos(), "ret.outside.meth");
1255
1256 } else {
1257 // Attribute return expression, if it exists, and check that
1258 // it conforms to result type of enclosing method.
1259 Symbol m = env.enclMethod.sym;
1260 if (m.type.getReturnType().tag == VOID) {
1261 if (tree.expr != null)
1262 log.error(tree.expr.pos(),
1263 "cant.ret.val.from.meth.decl.void");
1264 } else if (tree.expr == null) {
1265 log.error(tree.pos(), "missing.ret.val");
1266 } else {
1267 attribExpr(tree.expr, env, m.type.getReturnType());
1268 }
1269 }
1270 result = null;
1271 }
1272
1273 public void visitThrow(JCThrow tree) {
1274 attribExpr(tree.expr, env, syms.throwableType);
1275 result = null;
1276 }
1277
1278 public void visitAssert(JCAssert tree) {
1279 attribExpr(tree.cond, env, syms.booleanType);
1280 if (tree.detail != null) {
1281 chk.checkNonVoid(tree.detail.pos(), attribExpr(tree.detail, env));
1282 }
1283 result = null;
1284 }
1285
1286 /** Visitor method for method invocations.
1287 * NOTE: The method part of an application will have in its type field
1288 * the return type of the method, not the method's type itself!
1289 */
1290 public void visitApply(JCMethodInvocation tree) {
1291 // The local environment of a method application is
1292 // a new environment nested in the current one.
1293 Env<AttrContext> localEnv = env.dup(tree, env.info.dup());
1294
1295 // The types of the actual method arguments.
1296 List<Type> argtypes;
1297
1298 // The types of the actual method type arguments.
1299 List<Type> typeargtypes = null;
1300 boolean typeargtypesNonRefOK = false;
1301
1302 Name methName = TreeInfo.name(tree.meth);
1303
1304 boolean isConstructorCall =
1305 methName == names._this || methName == names._super;
1306
1307 if (isConstructorCall) {
1308 // We are seeing a ...this(...) or ...super(...) call.
1309 // Check that this is the first statement in a constructor.
1310 if (checkFirstConstructorStat(tree, env)) {
1311
1312 // Record the fact
1313 // that this is a constructor call (using isSelfCall).
1314 localEnv.info.isSelfCall = true;
1315
1316 // Attribute arguments, yielding list of argument types.
1317 argtypes = attribArgs(tree.args, localEnv);
1318 typeargtypes = attribTypes(tree.typeargs, localEnv);
1319
1320 // Variable `site' points to the class in which the called
1321 // constructor is defined.
1322 Type site = env.enclClass.sym.type;
1323 if (methName == names._super) {
1324 if (site == syms.objectType) {
1325 log.error(tree.meth.pos(), "no.superclass", site);
1326 site = types.createErrorType(syms.objectType);
1327 } else {
1328 site = types.supertype(site);
1329 }
1330 }
1331
1332 if (site.tag == CLASS) {
1333 Type encl = site.getEnclosingType();
1334 while (encl != null && encl.tag == TYPEVAR)
1335 encl = encl.getUpperBound();
1336 if (encl.tag == CLASS) {
1337 // we are calling a nested class
1338
1339 if (tree.meth.getTag() == JCTree.SELECT) {
1340 JCTree qualifier = ((JCFieldAccess) tree.meth).selected;
1341
1342 // We are seeing a prefixed call, of the form
1343 // <expr>.super(...).
1344 // Check that the prefix expression conforms
1345 // to the outer instance type of the class.
1346 chk.checkRefType(qualifier.pos(),
1347 attribExpr(qualifier, localEnv,
1348 encl));
1349 } else if (methName == names._super) {
1350 // qualifier omitted; check for existence
1351 // of an appropriate implicit qualifier.
1352 rs.resolveImplicitThis(tree.meth.pos(),
1353 localEnv, site);
1354 }
1355 } else if (tree.meth.getTag() == JCTree.SELECT) {
1356 log.error(tree.meth.pos(), "illegal.qual.not.icls",
1357 site.tsym);
1358 }
1359
1360 // if we're calling a java.lang.Enum constructor,
1361 // prefix the implicit String and int parameters
1362 if (site.tsym == syms.enumSym && allowEnums)
1363 argtypes = argtypes.prepend(syms.intType).prepend(syms.stringType);
1364
1365 // Resolve the called constructor under the assumption
1366 // that we are referring to a superclass instance of the
1367 // current instance (JLS ???).
1368 boolean selectSuperPrev = localEnv.info.selectSuper;
1369 localEnv.info.selectSuper = true;
1370 localEnv.info.varArgs = false;
1371 Symbol sym = rs.resolveConstructor(
1372 tree.meth.pos(), localEnv, site, argtypes, typeargtypes);
1373 localEnv.info.selectSuper = selectSuperPrev;
1374
1375 // Set method symbol to resolved constructor...
1376 TreeInfo.setSymbol(tree.meth, sym);
1377
1378 // ...and check that it is legal in the current context.
1379 // (this will also set the tree's type)
1380 Type mpt = newMethTemplate(argtypes, typeargtypes);
1381 checkId(tree.meth, site, sym, localEnv, MTH,
1382 mpt, tree.varargsElement != null);
1383 }
1384 // Otherwise, `site' is an error type and we do nothing
1385 }
1386 result = tree.type = syms.voidType;
1387 } else {
1388 // Otherwise, we are seeing a regular method call.
1389 // Attribute the arguments, yielding list of argument types, ...
1390 argtypes = attribArgs(tree.args, localEnv);
1391 typeargtypes = attribAnyTypes(tree.typeargs, localEnv);
1392
1393 // ... and attribute the method using as a prototype a methodtype
1394 // whose formal argument types is exactly the list of actual
1395 // arguments (this will also set the method symbol).
1396 Type mpt = newMethTemplate(argtypes, typeargtypes);
1397 localEnv.info.varArgs = false;
1398 Type mtype = attribExpr(tree.meth, localEnv, mpt);
1399 if (localEnv.info.varArgs)
1400 assert mtype.isErroneous() || tree.varargsElement != null;
1401
1402 // Compute the result type.
1403 Type restype = mtype.getReturnType();
1404 assert restype.tag != WILDCARD : mtype;
1405
1406 // as a special case, array.clone() has a result that is
1407 // the same as static type of the array being cloned
1408 if (tree.meth.getTag() == JCTree.SELECT &&
1409 allowCovariantReturns &&
1410 methName == names.clone &&
1411 types.isArray(((JCFieldAccess) tree.meth).selected.type))
1412 restype = ((JCFieldAccess) tree.meth).selected.type;
1413
1414 // as a special case, x.getClass() has type Class<? extends |X|>
1415 if (allowGenerics &&
1416 methName == names.getClass && tree.args.isEmpty()) {
1417 Type qualifier = (tree.meth.getTag() == JCTree.SELECT)
1418 ? ((JCFieldAccess) tree.meth).selected.type
1419 : env.enclClass.sym.type;
1420 restype = new
1421 ClassType(restype.getEnclosingType(),
1422 List.<Type>of(new WildcardType(types.erasure(qualifier),
1423 BoundKind.EXTENDS,
1424 syms.boundClass)),
1425 restype.tsym);
1426 }
1427
1428 // as a special case, MethodHandle.<T>invoke(abc) and InvokeDynamic.<T>foo(abc)
1429 // has type <T>, and T can be a primitive type.
1430 if (tree.meth.getTag() == JCTree.SELECT && !typeargtypes.isEmpty()) {
1431 Type selt = ((JCFieldAccess) tree.meth).selected.type;
1432 if ((selt == syms.methodHandleType && methName == names.invoke) || selt == syms.invokeDynamicType) {
1433 assert types.isSameType(restype, typeargtypes.head) : mtype;
1434 typeargtypesNonRefOK = true;
1435 }
1436 }
1437
1438 if (!typeargtypesNonRefOK) {
1439 chk.checkRefTypes(tree.typeargs, typeargtypes);
1440 }
1441
1442 // Check that value of resulting type is admissible in the
1443 // current context. Also, capture the return type
1444 result = check(tree, capture(restype), VAL, pkind, pt);
1445 }
1446 chk.validate(tree.typeargs, localEnv);
1447 }
1448 //where
1449 /** Check that given application node appears as first statement
1450 * in a constructor call.
1451 * @param tree The application node
1452 * @param env The environment current at the application.
1453 */
1454 boolean checkFirstConstructorStat(JCMethodInvocation tree, Env<AttrContext> env) {
1455 JCMethodDecl enclMethod = env.enclMethod;
1456 if (enclMethod != null && enclMethod.name == names.init) {
1457 JCBlock body = enclMethod.body;
1458 if (body.stats.head.getTag() == JCTree.EXEC &&
1459 ((JCExpressionStatement) body.stats.head).expr == tree)
1460 return true;
1461 }
1462 log.error(tree.pos(),"call.must.be.first.stmt.in.ctor",
1463 TreeInfo.name(tree.meth));
1464 return false;
1465 }
1466
1467 /** Obtain a method type with given argument types.
1468 */
1469 Type newMethTemplate(List<Type> argtypes, List<Type> typeargtypes) {
1470 MethodType mt = new MethodType(argtypes, null, null, syms.methodClass);
1471 return (typeargtypes == null) ? mt : (Type)new ForAll(typeargtypes, mt);
1472 }
1473
1474 public void visitNewClass(JCNewClass tree) {
1475 Type owntype = types.createErrorType(tree.type);
1476
1477 // The local environment of a class creation is
1478 // a new environment nested in the current one.
1479 Env<AttrContext> localEnv = env.dup(tree, env.info.dup());
1480
1481 // The anonymous inner class definition of the new expression,
1482 // if one is defined by it.
1483 JCClassDecl cdef = tree.def;
1484
1485 // If enclosing class is given, attribute it, and
1486 // complete class name to be fully qualified
1487 JCExpression clazz = tree.clazz; // Class field following new
1488 JCExpression clazzid = // Identifier in class field
1489 (clazz.getTag() == JCTree.TYPEAPPLY)
1490 ? ((JCTypeApply) clazz).clazz
1491 : clazz;
1492
1493 JCExpression clazzid1 = clazzid; // The same in fully qualified form
1494
1495 if (tree.encl != null) {
1496 // We are seeing a qualified new, of the form
1497 // <expr>.new C <...> (...) ...
1498 // In this case, we let clazz stand for the name of the
1499 // allocated class C prefixed with the type of the qualifier
1500 // expression, so that we can
1501 // resolve it with standard techniques later. I.e., if
1502 // <expr> has type T, then <expr>.new C <...> (...)
1503 // yields a clazz T.C.
1504 Type encltype = chk.checkRefType(tree.encl.pos(),
1505 attribExpr(tree.encl, env));
1506 clazzid1 = make.at(clazz.pos).Select(make.Type(encltype),
1507 ((JCIdent) clazzid).name);
1508 if (clazz.getTag() == JCTree.TYPEAPPLY)
1509 clazz = make.at(tree.pos).
1510 TypeApply(clazzid1,
1511 ((JCTypeApply) clazz).arguments);
1512 else
1513 clazz = clazzid1;
1514 }
1515
1516 // Attribute clazz expression and store
1517 // symbol + type back into the attributed tree.
1518 Type clazztype = attribType(clazz, env);
1519 Pair<Scope,Scope> mapping = getSyntheticScopeMapping(clazztype);
1520 if (!TreeInfo.isDiamond(tree)) {
1521 clazztype = chk.checkClassType(
1522 tree.clazz.pos(), clazztype, true);
1523 }
1524 chk.validate(clazz, localEnv);
1525 if (tree.encl != null) {
1526 // We have to work in this case to store
1527 // symbol + type back into the attributed tree.
1528 tree.clazz.type = clazztype;
1529 TreeInfo.setSymbol(clazzid, TreeInfo.symbol(clazzid1));
1530 clazzid.type = ((JCIdent) clazzid).sym.type;
1531 if (!clazztype.isErroneous()) {
1532 if (cdef != null && clazztype.tsym.isInterface()) {
1533 log.error(tree.encl.pos(), "anon.class.impl.intf.no.qual.for.new");
1534 } else if (clazztype.tsym.isStatic()) {
1535 log.error(tree.encl.pos(), "qualified.new.of.static.class", clazztype.tsym);
1536 }
1537 }
1538 } else if (!clazztype.tsym.isInterface() &&
1539 clazztype.getEnclosingType().tag == CLASS) {
1540 // Check for the existence of an apropos outer instance
1541 rs.resolveImplicitThis(tree.pos(), env, clazztype);
1542 }
1543
1544 // Attribute constructor arguments.
1545 List<Type> argtypes = attribArgs(tree.args, localEnv);
1546 List<Type> typeargtypes = attribTypes(tree.typeargs, localEnv);
1547
1548 if (TreeInfo.isDiamond(tree)) {
1549 clazztype = attribDiamond(localEnv, tree, clazztype, mapping, argtypes, typeargtypes, true);
1550 clazz.type = clazztype;
1551 }
1552
1553 // If we have made no mistakes in the class type...
1554 if (clazztype.tag == CLASS) {
1555 // Enums may not be instantiated except implicitly
1556 if (allowEnums &&
1557 (clazztype.tsym.flags_field&Flags.ENUM) != 0 &&
1558 (env.tree.getTag() != JCTree.VARDEF ||
1559 (((JCVariableDecl) env.tree).mods.flags&Flags.ENUM) == 0 ||
1560 ((JCVariableDecl) env.tree).init != tree))
1561 log.error(tree.pos(), "enum.cant.be.instantiated");
1562 // Check that class is not abstract
1563 if (cdef == null &&
1564 (clazztype.tsym.flags() & (ABSTRACT | INTERFACE)) != 0) {
1565 log.error(tree.pos(), "abstract.cant.be.instantiated",
1566 clazztype.tsym);
1567 } else if (cdef != null && clazztype.tsym.isInterface()) {
1568 // Check that no constructor arguments are given to
1569 // anonymous classes implementing an interface
1570 if (!argtypes.isEmpty())
1571 log.error(tree.args.head.pos(), "anon.class.impl.intf.no.args");
1572
1573 if (!typeargtypes.isEmpty())
1574 log.error(tree.typeargs.head.pos(), "anon.class.impl.intf.no.typeargs");
1575
1576 // Error recovery: pretend no arguments were supplied.
1577 argtypes = List.nil();
1578 typeargtypes = List.nil();
1579 }
1580
1581 // Resolve the called constructor under the assumption
1582 // that we are referring to a superclass instance of the
1583 // current instance (JLS ???).
1584 else {
1585 localEnv.info.selectSuper = cdef != null;
1586 localEnv.info.varArgs = false;
1587 tree.constructor = rs.resolveConstructor(
1588 tree.pos(), localEnv, clazztype, argtypes, typeargtypes);
1589 tree.constructorType = checkMethod(clazztype,
1590 tree.constructor,
1591 localEnv,
1592 tree.args,
1593 argtypes,
1594 typeargtypes,
1595 localEnv.info.varArgs);
1596 if (localEnv.info.varArgs)
1597 assert tree.constructorType.isErroneous() || tree.varargsElement != null;
1598 }
1599
1600 if (cdef != null) {
1601 // We are seeing an anonymous class instance creation.
1602 // In this case, the class instance creation
1603 // expression
1604 //
1605 // E.new <typeargs1>C<typargs2>(args) { ... }
1606 //
1607 // is represented internally as
1608 //
1609 // E . new <typeargs1>C<typargs2>(args) ( class <empty-name> { ... } ) .
1610 //
1611 // This expression is then *transformed* as follows:
1612 //
1613 // (1) add a STATIC flag to the class definition
1614 // if the current environment is static
1615 // (2) add an extends or implements clause
1616 // (3) add a constructor.
1617 //
1618 // For instance, if C is a class, and ET is the type of E,
1619 // the expression
1620 //
1621 // E.new <typeargs1>C<typargs2>(args) { ... }
1622 //
1623 // is translated to (where X is a fresh name and typarams is the
1624 // parameter list of the super constructor):
1625 //
1626 // new <typeargs1>X(<*nullchk*>E, args) where
1627 // X extends C<typargs2> {
1628 // <typarams> X(ET e, args) {
1629 // e.<typeargs1>super(args)
1630 // }
1631 // ...
1632 // }
1633 if (Resolve.isStatic(env)) cdef.mods.flags |= STATIC;
1634
1635 if (clazztype.tsym.isInterface()) {
1636 cdef.implementing = List.of(clazz);
1637 } else {
1638 cdef.extending = clazz;
1639 }
1640
1641 attribStat(cdef, localEnv);
1642
1643 // If an outer instance is given,
1644 // prefix it to the constructor arguments
1645 // and delete it from the new expression
1646 if (tree.encl != null && !clazztype.tsym.isInterface()) {
1647 tree.args = tree.args.prepend(makeNullCheck(tree.encl));
1648 argtypes = argtypes.prepend(tree.encl.type);
1649 tree.encl = null;
1650 }
1651
1652 // Reassign clazztype and recompute constructor.
1653 clazztype = cdef.sym.type;
1654 Symbol sym = rs.resolveConstructor(
1655 tree.pos(), localEnv, clazztype, argtypes,
1656 typeargtypes, true, tree.varargsElement != null);
1657 assert sym.kind < AMBIGUOUS || tree.constructor.type.isErroneous();
1658 tree.constructor = sym;
1659 if (tree.constructor.kind > ERRONEOUS) {
1660 tree.constructorType = syms.errType;
1661 }
1662 else {
1663 tree.constructorType = checkMethod(clazztype,
1664 tree.constructor,
1665 localEnv,
1666 tree.args,
1667 argtypes,
1668 typeargtypes,
1669 localEnv.info.varArgs);
1670 }
1671 }
1672
1673 if (tree.constructor != null && tree.constructor.kind == MTH)
1674 owntype = clazztype;
1675 }
1676 result = check(tree, owntype, VAL, pkind, pt);
1677 chk.validate(tree.typeargs, localEnv);
1678 }
1679
1680 Type attribDiamond(Env<AttrContext> env,
1681 JCNewClass tree,
1682 Type clazztype,
1683 Pair<Scope, Scope> mapping,
1684 List<Type> argtypes,
1685 List<Type> typeargtypes,
1686 boolean reportErrors) {
1687 if (clazztype.isErroneous() || mapping == erroneousMapping) {
1688 //if the type of the instance creation expression is erroneous,
1689 //or something prevented us to form a valid mapping, return the
1690 //(possibly erroneous) type unchanged
1691 return clazztype;
1692 }
1693 else if (clazztype.isInterface()) {
1694 //if the type of the instance creation expression is an interface
1695 //skip the method resolution step (JLS 15.12.2.7). The type to be
1696 //inferred is of the kind <X1,X2, ... Xn>C<X1,X2, ... Xn>
1697 clazztype = new ForAll(clazztype.tsym.type.allparams(),
1698 clazztype.tsym.type);
1699 } else {
1700 //if the type of the instance creation expression is a class type
1701 //apply method resolution inference (JLS 15.12.2.7). The return type
1702 //of the resolved constructor will be a partially instantiated type
1703 ((ClassSymbol) clazztype.tsym).members_field = mapping.snd;
1704 Symbol constructor;
1705 try {
1706 constructor = rs.resolveDiamond(tree.pos(),
1707 env,
1708 clazztype.tsym.type,
1709 argtypes,
1710 typeargtypes, reportErrors);
1711 } finally {
1712 ((ClassSymbol) clazztype.tsym).members_field = mapping.fst;
1713 }
1714 if (constructor.kind == MTH) {
1715 ClassType ct = new ClassType(clazztype.getEnclosingType(),
1716 clazztype.tsym.type.getTypeArguments(),
1717 clazztype.tsym);
1718 clazztype = checkMethod(ct,
1719 constructor,
1720 env,
1721 tree.args,
1722 argtypes,
1723 typeargtypes,
1724 env.info.varArgs).getReturnType();
1725 } else {
1726 clazztype = syms.errType;
1727 }
1728 }
1729 if (clazztype.tag == FORALL && !pt.isErroneous()) {
1730 //if the resolved constructor's return type has some uninferred
1731 //type-variables, infer them using the expected type and declared
1732 //bounds (JLS 15.12.2.8).
1733 try {
1734 clazztype = infer.instantiateExpr((ForAll) clazztype,
1735 pt.tag == NONE ? syms.objectType : pt,
1736 Warner.noWarnings);
1737 } catch (Infer.InferenceException ex) {
1738 //an error occurred while inferring uninstantiated type-variables
1739 //we need to optionally report an error
1740 if (reportErrors) {
1741 log.error(tree.clazz.pos(),
1742 "cant.apply.diamond.1",
1743 diags.fragment("diamond", clazztype.tsym),
1744 ex.diagnostic);
1745 }
1746 }
1747 }
1748 if (reportErrors) {
1749 clazztype = chk.checkClassType(tree.clazz.pos(),
1750 clazztype,
1751 true);
1752 if (clazztype.tag == CLASS) {
1753 List<Type> invalidDiamondArgs = chk.checkDiamond((ClassType)clazztype);
1754 if (!clazztype.isErroneous() && invalidDiamondArgs.nonEmpty()) {
1755 //one or more types inferred in the previous steps is either a
1756 //captured type or an intersection type --- we need to report an error.
1757 String subkey = invalidDiamondArgs.size() > 1 ?
1758 "diamond.invalid.args" :
1759 "diamond.invalid.arg";
1760 //The error message is of the kind:
1761 //
1762 //cannot infer type arguments for {clazztype}<>;
1763 //reason: {subkey}
1764 //
1765 //where subkey is a fragment of the kind:
1766 //
1767 //type argument(s) {invalidDiamondArgs} inferred for {clazztype}<> is not allowed in this context
1768 log.error(tree.clazz.pos(),
1769 "cant.apply.diamond.1",
1770 diags.fragment("diamond", clazztype.tsym),
1771 diags.fragment(subkey,
1772 invalidDiamondArgs,
1773 diags.fragment("diamond", clazztype.tsym)));
1774 }
1775 }
1776 }
1777 return clazztype;
1778 }
1779
1780 /** Creates a synthetic scope containing fake generic constructors.
1781 * Assuming that the original scope contains a constructor of the kind:
1782 * Foo(X x, Y y), where X,Y are class type-variables declared in Foo,
1783 * the synthetic scope is added a generic constructor of the kind:
1784 * <X,Y>Foo<X,Y>(X x, Y y). This is crucial in order to enable diamond
1785 * inference. The inferred return type of the synthetic constructor IS
1786 * the inferred type for the diamond operator.
1787 */
1788 private Pair<Scope, Scope> getSyntheticScopeMapping(Type ctype) {
1789 if (ctype.tag != CLASS) {
1790 return erroneousMapping;
1791 }
1792 Pair<Scope, Scope> mapping =
1793 new Pair<Scope, Scope>(ctype.tsym.members(), new Scope(ctype.tsym));
1794 List<Type> typevars = ctype.tsym.type.getTypeArguments();
1795 for (Scope.Entry e = mapping.fst.lookup(names.init);
1796 e.scope != null;
1797 e = e.next()) {
1798 MethodSymbol newConstr = (MethodSymbol) e.sym.clone(ctype.tsym);
1799 newConstr.name = names.init;
1800 List<Type> oldTypeargs = List.nil();
1801 if (newConstr.type.tag == FORALL) {
1802 oldTypeargs = ((ForAll) newConstr.type).tvars;
1803 }
1804 newConstr.type = new MethodType(newConstr.type.getParameterTypes(),
1805 new ClassType(ctype.getEnclosingType(), ctype.tsym.type.getTypeArguments(), ctype.tsym),
1806 newConstr.type.getThrownTypes(),
1807 syms.methodClass);
1808 newConstr.type = new ForAll(typevars.prependList(oldTypeargs), newConstr.type);
1809 mapping.snd.enter(newConstr);
1810 }
1811 return mapping;
1812 }
1813
1814 private final Pair<Scope,Scope> erroneousMapping = new Pair<Scope,Scope>(null, null);
1815
1816 /** Make an attributed null check tree.
1817 */
1818 public JCExpression makeNullCheck(JCExpression arg) {
1819 // optimization: X.this is never null; skip null check
1820 Name name = TreeInfo.name(arg);
1821 if (name == names._this || name == names._super) return arg;
1822
1823 int optag = JCTree.NULLCHK;
1824 JCUnary tree = make.at(arg.pos).Unary(optag, arg);
1825 tree.operator = syms.nullcheck;
1826 tree.type = arg.type;
1827 return tree;
1828 }
1829
1830 public void visitNewArray(JCNewArray tree) {
1831 Type owntype = types.createErrorType(tree.type);
1832 Type elemtype;
1833 if (tree.elemtype != null) {
1834 elemtype = attribType(tree.elemtype, env);
1835 chk.validate(tree.elemtype, env);
1836 owntype = elemtype;
1837 for (List<JCExpression> l = tree.dims; l.nonEmpty(); l = l.tail) {
1838 attribExpr(l.head, env, syms.intType);
1839 owntype = new ArrayType(owntype, syms.arrayClass);
1840 }
1841 } else {
1842 // we are seeing an untyped aggregate { ... }
1843 // this is allowed only if the prototype is an array
1844 if (pt.tag == ARRAY) {
1845 elemtype = types.elemtype(pt);
1846 } else {
1847 if (pt.tag != ERROR) {
1848 log.error(tree.pos(), "illegal.initializer.for.type",
1849 pt);
1850 }
1851 elemtype = types.createErrorType(pt);
1852 }
1853 }
1854 if (tree.elems != null) {
1855 attribExprs(tree.elems, env, elemtype);
1856 owntype = new ArrayType(elemtype, syms.arrayClass);
1857 }
1858 if (!types.isReifiable(elemtype))
1859 log.error(tree.pos(), "generic.array.creation");
1860 result = check(tree, owntype, VAL, pkind, pt);
1861 }
1862
1863 public void visitParens(JCParens tree) {
1864 Type owntype = attribTree(tree.expr, env, pkind, pt);
1865 result = check(tree, owntype, pkind, pkind, pt);
1866 Symbol sym = TreeInfo.symbol(tree);
1867 if (sym != null && (sym.kind&(TYP|PCK)) != 0)
1868 log.error(tree.pos(), "illegal.start.of.type");
1869 }
1870
1871 public void visitAssign(JCAssign tree) {
1872 Type owntype = attribTree(tree.lhs, env.dup(tree), VAR, Type.noType);
1873 Type capturedType = capture(owntype);
1874 attribExpr(tree.rhs, env, owntype);
1875 result = check(tree, capturedType, VAL, pkind, pt);
1876 }
1877
1878 public void visitAssignop(JCAssignOp tree) {
1879 // Attribute arguments.
1880 Type owntype = attribTree(tree.lhs, env, VAR, Type.noType);
1881 Type operand = attribExpr(tree.rhs, env);
1882 // Find operator.
1883 Symbol operator = tree.operator = rs.resolveBinaryOperator(
1884 tree.pos(), tree.getTag() - JCTree.ASGOffset, env,
1885 owntype, operand);
1886
1887 if (operator.kind == MTH) {
1888 chk.checkOperator(tree.pos(),
1889 (OperatorSymbol)operator,
1890 tree.getTag() - JCTree.ASGOffset,
1891 owntype,
1892 operand);
1893 chk.checkDivZero(tree.rhs.pos(), operator, operand);
1894 chk.checkCastable(tree.rhs.pos(),
1895 operator.type.getReturnType(),
1896 owntype);
1897 }
1898 result = check(tree, owntype, VAL, pkind, pt);
1899 }
1900
1901 public void visitUnary(JCUnary tree) {
1902 // Attribute arguments.
1903 Type argtype = (JCTree.PREINC <= tree.getTag() && tree.getTag() <= JCTree.POSTDEC)
1904 ? attribTree(tree.arg, env, VAR, Type.noType)
1905 : chk.checkNonVoid(tree.arg.pos(), attribExpr(tree.arg, env));
1906
1907 // Find operator.
1908 Symbol operator = tree.operator =
1909 rs.resolveUnaryOperator(tree.pos(), tree.getTag(), env, argtype);
1910
1911 Type owntype = types.createErrorType(tree.type);
1912 if (operator.kind == MTH) {
1913 owntype = (JCTree.PREINC <= tree.getTag() && tree.getTag() <= JCTree.POSTDEC)
1914 ? tree.arg.type
1915 : operator.type.getReturnType();
1916 int opc = ((OperatorSymbol)operator).opcode;
1917
1918 // If the argument is constant, fold it.
1919 if (argtype.constValue() != null) {
1920 Type ctype = cfolder.fold1(opc, argtype);
1921 if (ctype != null) {
1922 owntype = cfolder.coerce(ctype, owntype);
1923
1924 // Remove constant types from arguments to
1925 // conserve space. The parser will fold concatenations
1926 // of string literals; the code here also
1927 // gets rid of intermediate results when some of the
1928 // operands are constant identifiers.
1929 if (tree.arg.type.tsym == syms.stringType.tsym) {
1930 tree.arg.type = syms.stringType;
1931 }
1932 }
1933 }
1934 }
1935 result = check(tree, owntype, VAL, pkind, pt);
1936 }
1937
1938 public void visitBinary(JCBinary tree) {
1939 // Attribute arguments.
1940 Type left = chk.checkNonVoid(tree.lhs.pos(), attribExpr(tree.lhs, env));
1941 Type right = chk.checkNonVoid(tree.lhs.pos(), attribExpr(tree.rhs, env));
1942
1943 // Find operator.
1944 Symbol operator = tree.operator =
1945 rs.resolveBinaryOperator(tree.pos(), tree.getTag(), env, left, right);
1946
1947 Type owntype = types.createErrorType(tree.type);
1948 if (operator.kind == MTH) {
1949 owntype = operator.type.getReturnType();
1950 int opc = chk.checkOperator(tree.lhs.pos(),
1951 (OperatorSymbol)operator,
1952 tree.getTag(),
1953 left,
1954 right);
1955
1956 // If both arguments are constants, fold them.
1957 if (left.constValue() != null && right.constValue() != null) {
1958 Type ctype = cfolder.fold2(opc, left, right);
1959 if (ctype != null) {
1960 owntype = cfolder.coerce(ctype, owntype);
1961
1962 // Remove constant types from arguments to
1963 // conserve space. The parser will fold concatenations
1964 // of string literals; the code here also
1965 // gets rid of intermediate results when some of the
1966 // operands are constant identifiers.
1967 if (tree.lhs.type.tsym == syms.stringType.tsym) {
1968 tree.lhs.type = syms.stringType;
1969 }
1970 if (tree.rhs.type.tsym == syms.stringType.tsym) {
1971 tree.rhs.type = syms.stringType;
1972 }
1973 }
1974 }
1975
1976 // Check that argument types of a reference ==, != are
1977 // castable to each other, (JLS???).
1978 if ((opc == ByteCodes.if_acmpeq || opc == ByteCodes.if_acmpne)) {
1979 if (!types.isCastable(left, right, new Warner(tree.pos()))) {
1980 log.error(tree.pos(), "incomparable.types", left, right);
1981 }
1982 }
1983
1984 chk.checkDivZero(tree.rhs.pos(), operator, right);
1985 }
1986 result = check(tree, owntype, VAL, pkind, pt);
1987 }
1988
1989 public void visitTypeCast(JCTypeCast tree) {
1990 Type clazztype = attribType(tree.clazz, env);
1991 chk.validate(tree.clazz, env);
1992 Type exprtype = attribExpr(tree.expr, env, Infer.anyPoly);
1993 Type owntype = chk.checkCastable(tree.expr.pos(), exprtype, clazztype);
1994 if (exprtype.constValue() != null)
1995 owntype = cfolder.coerce(exprtype, owntype);
1996 result = check(tree, capture(owntype), VAL, pkind, pt);
1997 }
1998
1999 public void visitTypeTest(JCInstanceOf tree) {
2000 Type exprtype = chk.checkNullOrRefType(
2001 tree.expr.pos(), attribExpr(tree.expr, env));
2002 Type clazztype = chk.checkReifiableReferenceType(
2003 tree.clazz.pos(), attribType(tree.clazz, env));
2004 chk.validate(tree.clazz, env);
2005 chk.checkCastable(tree.expr.pos(), exprtype, clazztype);
2006 result = check(tree, syms.booleanType, VAL, pkind, pt);
2007 }
2008
2009 public void visitIndexed(JCArrayAccess tree) {
2010 Type owntype = types.createErrorType(tree.type);
2011 Type atype = attribExpr(tree.indexed, env);
2012 attribExpr(tree.index, env, syms.intType);
2013 if (types.isArray(atype))
2014 owntype = types.elemtype(atype);
2015 else if (atype.tag != ERROR)
2016 log.error(tree.pos(), "array.req.but.found", atype);
2017 if ((pkind & VAR) == 0) owntype = capture(owntype);
2018 result = check(tree, owntype, VAR, pkind, pt);
2019 }
2020
2021 public void visitIdent(JCIdent tree) {
2022 Symbol sym;
2023 boolean varArgs = false;
2024
2025 // Find symbol
2026 if (pt.tag == METHOD || pt.tag == FORALL) {
2027 // If we are looking for a method, the prototype `pt' will be a
2028 // method type with the type of the call's arguments as parameters.
2029 env.info.varArgs = false;
2030 sym = rs.resolveMethod(tree.pos(), env, tree.name, pt.getParameterTypes(), pt.getTypeArguments());
2031 varArgs = env.info.varArgs;
2032 } else if (tree.sym != null && tree.sym.kind != VAR) {
2033 sym = tree.sym;
2034 } else {
2035 sym = rs.resolveIdent(tree.pos(), env, tree.name, pkind);
2036 }
2037 tree.sym = sym;
2038
2039 // (1) Also find the environment current for the class where
2040 // sym is defined (`symEnv').
2041 // Only for pre-tiger versions (1.4 and earlier):
2042 // (2) Also determine whether we access symbol out of an anonymous
2043 // class in a this or super call. This is illegal for instance
2044 // members since such classes don't carry a this$n link.
2045 // (`noOuterThisPath').
2046 Env<AttrContext> symEnv = env;
2047 boolean noOuterThisPath = false;
2048 if (env.enclClass.sym.owner.kind != PCK && // we are in an inner class
2049 (sym.kind & (VAR | MTH | TYP)) != 0 &&
2050 sym.owner.kind == TYP &&
2051 tree.name != names._this && tree.name != names._super) {
2052
2053 // Find environment in which identifier is defined.
2054 while (symEnv.outer != null &&
2055 !sym.isMemberOf(symEnv.enclClass.sym, types)) {
2056 if ((symEnv.enclClass.sym.flags() & NOOUTERTHIS) != 0)
2057 noOuterThisPath = !allowAnonOuterThis;
2058 symEnv = symEnv.outer;
2059 }
2060 }
2061
2062 // If symbol is a variable, ...
2063 if (sym.kind == VAR) {
2064 VarSymbol v = (VarSymbol)sym;
2065
2066 // ..., evaluate its initializer, if it has one, and check for
2067 // illegal forward reference.
2068 checkInit(tree, env, v, false);
2069
2070 // If symbol is a local variable accessed from an embedded
2071 // inner class check that it is final.
2072 if (v.owner.kind == MTH &&
2073 v.owner != env.info.scope.owner &&
2074 (v.flags_field & FINAL) == 0) {
2075 log.error(tree.pos(),
2076 "local.var.accessed.from.icls.needs.final",
2077 v);
2078 }
2079
2080 // If we are expecting a variable (as opposed to a value), check
2081 // that the variable is assignable in the current environment.
2082 if (pkind == VAR)
2083 checkAssignable(tree.pos(), v, null, env);
2084 }
2085
2086 // In a constructor body,
2087 // if symbol is a field or instance method, check that it is
2088 // not accessed before the supertype constructor is called.
2089 if ((symEnv.info.isSelfCall || noOuterThisPath) &&
2090 (sym.kind & (VAR | MTH)) != 0 &&
2091 sym.owner.kind == TYP &&
2092 (sym.flags() & STATIC) == 0) {
2093 chk.earlyRefError(tree.pos(), sym.kind == VAR ? sym : thisSym(tree.pos(), env));
2094 }
2095 Env<AttrContext> env1 = env;
2096 if (sym.kind != ERR && sym.kind != TYP && sym.owner != null && sym.owner != env1.enclClass.sym) {
2097 // If the found symbol is inaccessible, then it is
2098 // accessed through an enclosing instance. Locate this
2099 // enclosing instance:
2100 while (env1.outer != null && !rs.isAccessible(env, env1.enclClass.sym.type, sym))
2101 env1 = env1.outer;
2102 }
2103 result = checkId(tree, env1.enclClass.sym.type, sym, env, pkind, pt, varArgs);
2104 }
2105
2106 public void visitSelect(JCFieldAccess tree) {
2107 // Determine the expected kind of the qualifier expression.
2108 int skind = 0;
2109 if (tree.name == names._this || tree.name == names._super ||
2110 tree.name == names._class)
2111 {
2112 skind = TYP;
2113 } else {
2114 if ((pkind & PCK) != 0) skind = skind | PCK;
2115 if ((pkind & TYP) != 0) skind = skind | TYP | PCK;
2116 if ((pkind & (VAL | MTH)) != 0) skind = skind | VAL | TYP;
2117 }
2118
2119 // Attribute the qualifier expression, and determine its symbol (if any).
2120 Type site = attribTree(tree.selected, env, skind, Infer.anyPoly);
2121 if ((pkind & (PCK | TYP)) == 0)
2122 site = capture(site); // Capture field access
2123
2124 // don't allow T.class T[].class, etc
2125 if (skind == TYP) {
2126 Type elt = site;
2127 while (elt.tag == ARRAY)
2128 elt = ((ArrayType)elt).elemtype;
2129 if (elt.tag == TYPEVAR) {
2130 log.error(tree.pos(), "type.var.cant.be.deref");
2131 result = types.createErrorType(tree.type);
2132 return;
2133 }
2134 }
2135
2136 // If qualifier symbol is a type or `super', assert `selectSuper'
2137 // for the selection. This is relevant for determining whether
2138 // protected symbols are accessible.
2139 Symbol sitesym = TreeInfo.symbol(tree.selected);
2140 boolean selectSuperPrev = env.info.selectSuper;
2141 env.info.selectSuper =
2142 sitesym != null &&
2143 sitesym.name == names._super;
2144
2145 // If selected expression is polymorphic, strip
2146 // type parameters and remember in env.info.tvars, so that
2147 // they can be added later (in Attr.checkId and Infer.instantiateMethod).
2148 if (tree.selected.type.tag == FORALL) {
2149 ForAll pstype = (ForAll)tree.selected.type;
2150 env.info.tvars = pstype.tvars;
2151 site = tree.selected.type = pstype.qtype;
2152 }
2153
2154 // Determine the symbol represented by the selection.
2155 env.info.varArgs = false;
2156 Symbol sym = selectSym(tree, site, env, pt, pkind);
2157 if (sym.exists() && !isType(sym) && (pkind & (PCK | TYP)) != 0) {
2158 site = capture(site);
2159 sym = selectSym(tree, site, env, pt, pkind);
2160 }
2161 boolean varArgs = env.info.varArgs;
2162 tree.sym = sym;
2163
2164 if (site.tag == TYPEVAR && !isType(sym) && sym.kind != ERR) {
2165 while (site.tag == TYPEVAR) site = site.getUpperBound();
2166 site = capture(site);
2167 }
2168
2169 // If that symbol is a variable, ...
2170 if (sym.kind == VAR) {
2171 VarSymbol v = (VarSymbol)sym;
2172
2173 // ..., evaluate its initializer, if it has one, and check for
2174 // illegal forward reference.
2175 checkInit(tree, env, v, true);
2176
2177 // If we are expecting a variable (as opposed to a value), check
2178 // that the variable is assignable in the current environment.
2179 if (pkind == VAR)
2180 checkAssignable(tree.pos(), v, tree.selected, env);
2181 }
2182
2183 if (sitesym != null &&
2184 sitesym.kind == VAR &&
2185 ((VarSymbol)sitesym).isResourceVariable() &&
2186 sym.kind == MTH &&
2187 sym.name == names.close &&
2188 env.info.lint.isEnabled(Lint.LintCategory.ARM)) {
2189 log.warning(tree, "arm.explicit.close.call");
2190 }
2191
2192 // Disallow selecting a type from an expression
2193 if (isType(sym) && (sitesym==null || (sitesym.kind&(TYP|PCK)) == 0)) {
2194 tree.type = check(tree.selected, pt,
2195 sitesym == null ? VAL : sitesym.kind, TYP|PCK, pt);
2196 }
2197
2198 if (isType(sitesym)) {
2199 if (sym.name == names._this) {
2200 // If `C' is the currently compiled class, check that
2201 // C.this' does not appear in a call to a super(...)
2202 if (env.info.isSelfCall &&
2203 site.tsym == env.enclClass.sym) {
2204 chk.earlyRefError(tree.pos(), sym);
2205 }
2206 } else {
2207 // Check if type-qualified fields or methods are static (JLS)
2208 if ((sym.flags() & STATIC) == 0 &&
2209 sym.name != names._super &&
2210 (sym.kind == VAR || sym.kind == MTH)) {
2211 rs.access(rs.new StaticError(sym),
2212 tree.pos(), site, sym.name, true);
2213 }
2214 }
2215 } else if (sym.kind != ERR && (sym.flags() & STATIC) != 0 && sym.name != names._class) {
2216 // If the qualified item is not a type and the selected item is static, report
2217 // a warning. Make allowance for the class of an array type e.g. Object[].class)
2218 chk.warnStatic(tree, "static.not.qualified.by.type", Kinds.kindName(sym.kind), sym.owner);
2219 }
2220
2221 // If we are selecting an instance member via a `super', ...
2222 if (env.info.selectSuper && (sym.flags() & STATIC) == 0) {
2223
2224 // Check that super-qualified symbols are not abstract (JLS)
2225 rs.checkNonAbstract(tree.pos(), sym);
2226
2227 if (site.isRaw()) {
2228 // Determine argument types for site.
2229 Type site1 = types.asSuper(env.enclClass.sym.type, site.tsym);
2230 if (site1 != null) site = site1;
2231 }
2232 }
2233
2234 env.info.selectSuper = selectSuperPrev;
2235 result = checkId(tree, site, sym, env, pkind, pt, varArgs);
2236 env.info.tvars = List.nil();
2237 }
2238 //where
2239 /** Determine symbol referenced by a Select expression,
2240 *
2241 * @param tree The select tree.
2242 * @param site The type of the selected expression,
2243 * @param env The current environment.
2244 * @param pt The current prototype.
2245 * @param pkind The expected kind(s) of the Select expression.
2246 */
2247 private Symbol selectSym(JCFieldAccess tree,
2248 Type site,
2249 Env<AttrContext> env,
2250 Type pt,
2251 int pkind) {
2252 DiagnosticPosition pos = tree.pos();
2253 Name name = tree.name;
2254
2255 switch (site.tag) {
2256 case PACKAGE:
2257 return rs.access(
2258 rs.findIdentInPackage(env, site.tsym, name, pkind),
2259 pos, site, name, true);
2260 case ARRAY:
2261 case CLASS:
2262 if (pt.tag == METHOD || pt.tag == FORALL) {
2263 return rs.resolveQualifiedMethod(
2264 pos, env, site, name, pt.getParameterTypes(), pt.getTypeArguments());
2265 } else if (name == names._this || name == names._super) {
2266 return rs.resolveSelf(pos, env, site.tsym, name);
2267 } else if (name == names._class) {
2268 // In this case, we have already made sure in
2269 // visitSelect that qualifier expression is a type.
2270 Type t = syms.classType;
2271 List<Type> typeargs = allowGenerics
2272 ? List.of(types.erasure(site))
2273 : List.<Type>nil();
2274 t = new ClassType(t.getEnclosingType(), typeargs, t.tsym);
2275 return new VarSymbol(
2276 STATIC | PUBLIC | FINAL, names._class, t, site.tsym);
2277 } else {
2278 // We are seeing a plain identifier as selector.
2279 Symbol sym = rs.findIdentInType(env, site, name, pkind);
2280 if ((pkind & ERRONEOUS) == 0)
2281 sym = rs.access(sym, pos, site, name, true);
2282 return sym;
2283 }
2284 case WILDCARD:
2285 throw new AssertionError(tree);
2286 case TYPEVAR:
2287 // Normally, site.getUpperBound() shouldn't be null.
2288 // It should only happen during memberEnter/attribBase
2289 // when determining the super type which *must* be
2290 // done before attributing the type variables. In
2291 // other words, we are seeing this illegal program:
2292 // class B<T> extends A<T.foo> {}
2293 Symbol sym = (site.getUpperBound() != null)
2294 ? selectSym(tree, capture(site.getUpperBound()), env, pt, pkind)
2295 : null;
2296 if (sym == null) {
2297 log.error(pos, "type.var.cant.be.deref");
2298 return syms.errSymbol;
2299 } else {
2300 Symbol sym2 = (sym.flags() & Flags.PRIVATE) != 0 ?
2301 rs.new AccessError(env, site, sym) :
2302 sym;
2303 rs.access(sym2, pos, site, name, true);
2304 return sym;
2305 }
2306 case ERROR:
2307 // preserve identifier names through errors
2308 return types.createErrorType(name, site.tsym, site).tsym;
2309 default:
2310 // The qualifier expression is of a primitive type -- only
2311 // .class is allowed for these.
2312 if (name == names._class) {
2313 // In this case, we have already made sure in Select that
2314 // qualifier expression is a type.
2315 Type t = syms.classType;
2316 Type arg = types.boxedClass(site).type;
2317 t = new ClassType(t.getEnclosingType(), List.of(arg), t.tsym);
2318 return new VarSymbol(
2319 STATIC | PUBLIC | FINAL, names._class, t, site.tsym);
2320 } else {
2321 log.error(pos, "cant.deref", site);
2322 return syms.errSymbol;
2323 }
2324 }
2325 }
2326
2327 /** Determine type of identifier or select expression and check that
2328 * (1) the referenced symbol is not deprecated
2329 * (2) the symbol's type is safe (@see checkSafe)
2330 * (3) if symbol is a variable, check that its type and kind are
2331 * compatible with the prototype and protokind.
2332 * (4) if symbol is an instance field of a raw type,
2333 * which is being assigned to, issue an unchecked warning if its
2334 * type changes under erasure.
2335 * (5) if symbol is an instance method of a raw type, issue an
2336 * unchecked warning if its argument types change under erasure.
2337 * If checks succeed:
2338 * If symbol is a constant, return its constant type
2339 * else if symbol is a method, return its result type
2340 * otherwise return its type.
2341 * Otherwise return errType.
2342 *
2343 * @param tree The syntax tree representing the identifier
2344 * @param site If this is a select, the type of the selected
2345 * expression, otherwise the type of the current class.
2346 * @param sym The symbol representing the identifier.
2347 * @param env The current environment.
2348 * @param pkind The set of expected kinds.
2349 * @param pt The expected type.
2350 */
2351 Type checkId(JCTree tree,
2352 Type site,
2353 Symbol sym,
2354 Env<AttrContext> env,
2355 int pkind,
2356 Type pt,
2357 boolean useVarargs) {
2358 if (pt.isErroneous()) return types.createErrorType(site);
2359 Type owntype; // The computed type of this identifier occurrence.
2360 switch (sym.kind) {
2361 case TYP:
2362 // For types, the computed type equals the symbol's type,
2363 // except for two situations:
2364 owntype = sym.type;
2365 if (owntype.tag == CLASS) {
2366 Type ownOuter = owntype.getEnclosingType();
2367
2368 // (a) If the symbol's type is parameterized, erase it
2369 // because no type parameters were given.
2370 // We recover generic outer type later in visitTypeApply.
2371 if (owntype.tsym.type.getTypeArguments().nonEmpty()) {
2372 owntype = types.erasure(owntype);
2373 }
2374
2375 // (b) If the symbol's type is an inner class, then
2376 // we have to interpret its outer type as a superclass
2377 // of the site type. Example:
2378 //
2379 // class Tree<A> { class Visitor { ... } }
2380 // class PointTree extends Tree<Point> { ... }
2381 // ...PointTree.Visitor...
2382 //
2383 // Then the type of the last expression above is
2384 // Tree<Point>.Visitor.
2385 else if (ownOuter.tag == CLASS && site != ownOuter) {
2386 Type normOuter = site;
2387 if (normOuter.tag == CLASS)
2388 normOuter = types.asEnclosingSuper(site, ownOuter.tsym);
2389 if (normOuter == null) // perhaps from an import
2390 normOuter = types.erasure(ownOuter);
2391 if (normOuter != ownOuter)
2392 owntype = new ClassType(
2393 normOuter, List.<Type>nil(), owntype.tsym);
2394 }
2395 }
2396 break;
2397 case VAR:
2398 VarSymbol v = (VarSymbol)sym;
2399 // Test (4): if symbol is an instance field of a raw type,
2400 // which is being assigned to, issue an unchecked warning if
2401 // its type changes under erasure.
2402 if (allowGenerics &&
2403 pkind == VAR &&
2404 v.owner.kind == TYP &&
2405 (v.flags() & STATIC) == 0 &&
2406 (site.tag == CLASS || site.tag == TYPEVAR)) {
2407 Type s = types.asOuterSuper(site, v.owner);
2408 if (s != null &&
2409 s.isRaw() &&
2410 !types.isSameType(v.type, v.erasure(types))) {
2411 chk.warnUnchecked(tree.pos(),
2412 "unchecked.assign.to.var",
2413 v, s);
2414 }
2415 }
2416 // The computed type of a variable is the type of the
2417 // variable symbol, taken as a member of the site type.
2418 owntype = (sym.owner.kind == TYP &&
2419 sym.name != names._this && sym.name != names._super)
2420 ? types.memberType(site, sym)
2421 : sym.type;
2422
2423 if (env.info.tvars.nonEmpty()) {
2424 Type owntype1 = new ForAll(env.info.tvars, owntype);
2425 for (List<Type> l = env.info.tvars; l.nonEmpty(); l = l.tail)
2426 if (!owntype.contains(l.head)) {
2427 log.error(tree.pos(), "undetermined.type", owntype1);
2428 owntype1 = types.createErrorType(owntype1);
2429 }
2430 owntype = owntype1;
2431 }
2432
2433 // If the variable is a constant, record constant value in
2434 // computed type.
2435 if (v.getConstValue() != null && isStaticReference(tree))
2436 owntype = owntype.constType(v.getConstValue());
2437
2438 if (pkind == VAL) {
2439 owntype = capture(owntype); // capture "names as expressions"
2440 }
2441 break;
2442 case MTH: {
2443 JCMethodInvocation app = (JCMethodInvocation)env.tree;
2444 owntype = checkMethod(site, sym, env, app.args,
2445 pt.getParameterTypes(), pt.getTypeArguments(),
2446 env.info.varArgs);
2447 break;
2448 }
2449 case PCK: case ERR:
2450 owntype = sym.type;
2451 break;
2452 default:
2453 throw new AssertionError("unexpected kind: " + sym.kind +
2454 " in tree " + tree);
2455 }
2456
2457 // Test (1): emit a `deprecation' warning if symbol is deprecated.
2458 // (for constructors, the error was given when the constructor was
2459 // resolved)
2460 if (sym.name != names.init &&
2461 (sym.flags() & DEPRECATED) != 0 &&
2462 (env.info.scope.owner.flags() & DEPRECATED) == 0 &&
2463 sym.outermostClass() != env.info.scope.owner.outermostClass())
2464 chk.warnDeprecated(tree.pos(), sym);
2465
2466 if ((sym.flags() & PROPRIETARY) != 0) {
2467 if (enableSunApiLintControl)
2468 chk.warnSunApi(tree.pos(), "sun.proprietary", sym);
2469 else
2470 log.strictWarning(tree.pos(), "sun.proprietary", sym);
2471 }
2472
2473 // Test (3): if symbol is a variable, check that its type and
2474 // kind are compatible with the prototype and protokind.
2475 return check(tree, owntype, sym.kind, pkind, pt);
2476 }
2477
2478 /** Check that variable is initialized and evaluate the variable's
2479 * initializer, if not yet done. Also check that variable is not
2480 * referenced before it is defined.
2481 * @param tree The tree making up the variable reference.
2482 * @param env The current environment.
2483 * @param v The variable's symbol.
2484 */
2485 private void checkInit(JCTree tree,
2486 Env<AttrContext> env,
2487 VarSymbol v,
2488 boolean onlyWarning) {
2489 // System.err.println(v + " " + ((v.flags() & STATIC) != 0) + " " +
2490 // tree.pos + " " + v.pos + " " +
2491 // Resolve.isStatic(env));//DEBUG
2492
2493 // A forward reference is diagnosed if the declaration position
2494 // of the variable is greater than the current tree position
2495 // and the tree and variable definition occur in the same class
2496 // definition. Note that writes don't count as references.
2497 // This check applies only to class and instance
2498 // variables. Local variables follow different scope rules,
2499 // and are subject to definite assignment checking.
2500 if ((env.info.enclVar == v || v.pos > tree.pos) &&
2501 v.owner.kind == TYP &&
2502 canOwnInitializer(env.info.scope.owner) &&
2503 v.owner == env.info.scope.owner.enclClass() &&
2504 ((v.flags() & STATIC) != 0) == Resolve.isStatic(env) &&
2505 (env.tree.getTag() != JCTree.ASSIGN ||
2506 TreeInfo.skipParens(((JCAssign) env.tree).lhs) != tree)) {
2507 String suffix = (env.info.enclVar == v) ?
2508 "self.ref" : "forward.ref";
2509 if (!onlyWarning || isStaticEnumField(v)) {
2510 log.error(tree.pos(), "illegal." + suffix);
2511 } else if (useBeforeDeclarationWarning) {
2512 log.warning(tree.pos(), suffix, v);
2513 }
2514 }
2515
2516 v.getConstValue(); // ensure initializer is evaluated
2517
2518 checkEnumInitializer(tree, env, v);
2519 }
2520
2521 /**
2522 * Check for illegal references to static members of enum. In
2523 * an enum type, constructors and initializers may not
2524 * reference its static members unless they are constant.
2525 *
2526 * @param tree The tree making up the variable reference.
2527 * @param env The current environment.
2528 * @param v The variable's symbol.
2529 * @see JLS 3rd Ed. (8.9 Enums)
2530 */
2531 private void checkEnumInitializer(JCTree tree, Env<AttrContext> env, VarSymbol v) {
2532 // JLS 3rd Ed.:
2533 //
2534 // "It is a compile-time error to reference a static field
2535 // of an enum type that is not a compile-time constant
2536 // (15.28) from constructors, instance initializer blocks,
2537 // or instance variable initializer expressions of that
2538 // type. It is a compile-time error for the constructors,
2539 // instance initializer blocks, or instance variable
2540 // initializer expressions of an enum constant e to refer
2541 // to itself or to an enum constant of the same type that
2542 // is declared to the right of e."
2543 if (isStaticEnumField(v)) {
2544 ClassSymbol enclClass = env.info.scope.owner.enclClass();
2545
2546 if (enclClass == null || enclClass.owner == null)
2547 return;
2548
2549 // See if the enclosing class is the enum (or a
2550 // subclass thereof) declaring v. If not, this
2551 // reference is OK.
2552 if (v.owner != enclClass && !types.isSubtype(enclClass.type, v.owner.type))
2553 return;
2554
2555 // If the reference isn't from an initializer, then
2556 // the reference is OK.
2557 if (!Resolve.isInitializer(env))
2558 return;
2559
2560 log.error(tree.pos(), "illegal.enum.static.ref");
2561 }
2562 }
2563
2564 /** Is the given symbol a static, non-constant field of an Enum?
2565 * Note: enum literals should not be regarded as such
2566 */
2567 private boolean isStaticEnumField(VarSymbol v) {
2568 return Flags.isEnum(v.owner) &&
2569 Flags.isStatic(v) &&
2570 !Flags.isConstant(v) &&
2571 v.name != names._class;
2572 }
2573
2574 /** Can the given symbol be the owner of code which forms part
2575 * if class initialization? This is the case if the symbol is
2576 * a type or field, or if the symbol is the synthetic method.
2577 * owning a block.
2578 */
2579 private boolean canOwnInitializer(Symbol sym) {
2580 return
2581 (sym.kind & (VAR | TYP)) != 0 ||
2582 (sym.kind == MTH && (sym.flags() & BLOCK) != 0);
2583 }
2584
2585 Warner noteWarner = new Warner();
2586
2587 /**
2588 * Check that method arguments conform to its instantation.
2589 **/
2590 public Type checkMethod(Type site,
2591 Symbol sym,
2592 Env<AttrContext> env,
2593 final List<JCExpression> argtrees,
2594 List<Type> argtypes,
2595 List<Type> typeargtypes,
2596 boolean useVarargs) {
2597 // Test (5): if symbol is an instance method of a raw type, issue
2598 // an unchecked warning if its argument types change under erasure.
2599 if (allowGenerics &&
2600 (sym.flags() & STATIC) == 0 &&
2601 (site.tag == CLASS || site.tag == TYPEVAR)) {
2602 Type s = types.asOuterSuper(site, sym.owner);
2603 if (s != null && s.isRaw() &&
2604 !types.isSameTypes(sym.type.getParameterTypes(),
2605 sym.erasure(types).getParameterTypes())) {
2606 chk.warnUnchecked(env.tree.pos(),
2607 "unchecked.call.mbr.of.raw.type",
2608 sym, s);
2609 }
2610 }
2611
2612 // Compute the identifier's instantiated type.
2613 // For methods, we need to compute the instance type by
2614 // Resolve.instantiate from the symbol's type as well as
2615 // any type arguments and value arguments.
2616 noteWarner.warned = false;
2617 Type owntype = rs.instantiate(env,
2618 site,
2619 sym,
2620 argtypes,
2621 typeargtypes,
2622 true,
2623 useVarargs,
2624 noteWarner);
2625 boolean warned = noteWarner.warned;
2626
2627 // If this fails, something went wrong; we should not have
2628 // found the identifier in the first place.
2629 if (owntype == null) {
2630 if (!pt.isErroneous())
2631 log.error(env.tree.pos(),
2632 "internal.error.cant.instantiate",
2633 sym, site,
2634 Type.toString(pt.getParameterTypes()));
2635 owntype = types.createErrorType(site);
2636 } else {
2637 // System.out.println("call : " + env.tree);
2638 // System.out.println("method : " + owntype);
2639 // System.out.println("actuals: " + argtypes);
2640 List<Type> formals = owntype.getParameterTypes();
2641 Type last = useVarargs ? formals.last() : null;
2642 if (sym.name==names.init &&
2643 sym.owner == syms.enumSym)
2644 formals = formals.tail.tail;
2645 List<JCExpression> args = argtrees;
2646 while (formals.head != last) {
2647 JCTree arg = args.head;
2648 Warner warn = chk.convertWarner(arg.pos(), arg.type, formals.head);
2649 assertConvertible(arg, arg.type, formals.head, warn);
2650 warned |= warn.warned;
2651 args = args.tail;
2652 formals = formals.tail;
2653 }
2654 if (useVarargs) {
2655 Type varArg = types.elemtype(last);
2656 while (args.tail != null) {
2657 JCTree arg = args.head;
2658 Warner warn = chk.convertWarner(arg.pos(), arg.type, varArg);
2659 assertConvertible(arg, arg.type, varArg, warn);
2660 warned |= warn.warned;
2661 args = args.tail;
2662 }
2663 } else if ((sym.flags() & VARARGS) != 0 && allowVarargs) {
2664 // non-varargs call to varargs method
2665 Type varParam = owntype.getParameterTypes().last();
2666 Type lastArg = argtypes.last();
2667 if (types.isSubtypeUnchecked(lastArg, types.elemtype(varParam)) &&
2668 !types.isSameType(types.erasure(varParam), types.erasure(lastArg)))
2669 log.warning(argtrees.last().pos(), "inexact.non-varargs.call",
2670 types.elemtype(varParam),
2671 varParam);
2672 }
2673
2674 if (warned && sym.type.tag == FORALL) {
2675 chk.warnUnchecked(env.tree.pos(),
2676 "unchecked.meth.invocation.applied",
2677 kindName(sym),
2678 sym.name,
2679 rs.methodArguments(sym.type.getParameterTypes()),
2680 rs.methodArguments(argtypes),
2681 kindName(sym.location()),
2682 sym.location());
2683 owntype = new MethodType(owntype.getParameterTypes(),
2684 types.erasure(owntype.getReturnType()),
2685 owntype.getThrownTypes(),
2686 syms.methodClass);
2687 }
2688 if (useVarargs) {
2689 JCTree tree = env.tree;
2690 Type argtype = owntype.getParameterTypes().last();
2691 if (owntype.getReturnType().tag != FORALL || warned) {
2692 chk.checkVararg(env.tree.pos(), owntype.getParameterTypes(), sym, env);
2693 }
2694 Type elemtype = types.elemtype(argtype);
2695 switch (tree.getTag()) {
2696 case JCTree.APPLY:
2697 ((JCMethodInvocation) tree).varargsElement = elemtype;
2698 break;
2699 case JCTree.NEWCLASS:
2700 ((JCNewClass) tree).varargsElement = elemtype;
2701 break;
2702 default:
2703 throw new AssertionError(""+tree);
2704 }
2705 }
2706 }
2707 return owntype;
2708 }
2709
2710 private void assertConvertible(JCTree tree, Type actual, Type formal, Warner warn) {
2711 if (types.isConvertible(actual, formal, warn))
2712 return;
2713
2714 if (formal.isCompound()
2715 && types.isSubtype(actual, types.supertype(formal))
2716 && types.isSubtypeUnchecked(actual, types.interfaces(formal), warn))
2717 return;
2718
2719 if (false) {
2720 // TODO: make assertConvertible work
2721 chk.typeError(tree.pos(), diags.fragment("incompatible.types"), actual, formal);
2722 throw new AssertionError("Tree: " + tree
2723 + " actual:" + actual
2724 + " formal: " + formal);
2725 }
2726 }
2727
2728 public void visitLiteral(JCLiteral tree) {
2729 result = check(
2730 tree, litType(tree.typetag).constType(tree.value), VAL, pkind, pt);
2731 }
2732 //where
2733 /** Return the type of a literal with given type tag.
2734 */
2735 Type litType(int tag) {
2736 return (tag == TypeTags.CLASS) ? syms.stringType : syms.typeOfTag[tag];
2737 }
2738
2739 public void visitTypeIdent(JCPrimitiveTypeTree tree) {
2740 result = check(tree, syms.typeOfTag[tree.typetag], TYP, pkind, pt);
2741 }
2742
2743 public void visitTypeArray(JCArrayTypeTree tree) {
2744 Type etype = attribType(tree.elemtype, env);
2745 Type type = new ArrayType(etype, syms.arrayClass);
2746 result = check(tree, type, TYP, pkind, pt);
2747 }
2748
2749 /** Visitor method for parameterized types.
2750 * Bound checking is left until later, since types are attributed
2751 * before supertype structure is completely known
2752 */
2753 public void visitTypeApply(JCTypeApply tree) {
2754 Type owntype = types.createErrorType(tree.type);
2755
2756 // Attribute functor part of application and make sure it's a class.
2757 Type clazztype = chk.checkClassType(tree.clazz.pos(), attribType(tree.clazz, env));
2758
2759 // Attribute type parameters
2760 List<Type> actuals = attribTypes(tree.arguments, env);
2761
2762 if (clazztype.tag == CLASS) {
2763 List<Type> formals = clazztype.tsym.type.getTypeArguments();
2764
2765 if (actuals.length() == formals.length() || actuals.length() == 0) {
2766 List<Type> a = actuals;
2767 List<Type> f = formals;
2768 while (a.nonEmpty()) {
2769 a.head = a.head.withTypeVar(f.head);
2770 a = a.tail;
2771 f = f.tail;
2772 }
2773 // Compute the proper generic outer
2774 Type clazzOuter = clazztype.getEnclosingType();
2775 if (clazzOuter.tag == CLASS) {
2776 Type site;
2777 JCExpression clazz = TreeInfo.typeIn(tree.clazz);
2778 if (clazz.getTag() == JCTree.IDENT) {
2779 site = env.enclClass.sym.type;
2780 } else if (clazz.getTag() == JCTree.SELECT) {
2781 site = ((JCFieldAccess) clazz).selected.type;
2782 } else throw new AssertionError(""+tree);
2783 if (clazzOuter.tag == CLASS && site != clazzOuter) {
2784 if (site.tag == CLASS)
2785 site = types.asOuterSuper(site, clazzOuter.tsym);
2786 if (site == null)
2787 site = types.erasure(clazzOuter);
2788 clazzOuter = site;
2789 }
2790 }
2791 owntype = new ClassType(clazzOuter, actuals, clazztype.tsym);
2792 } else {
2793 if (formals.length() != 0) {
2794 log.error(tree.pos(), "wrong.number.type.args",
2795 Integer.toString(formals.length()));
2796 } else {
2797 log.error(tree.pos(), "type.doesnt.take.params", clazztype.tsym);
2798 }
2799 owntype = types.createErrorType(tree.type);
2800 }
2801 }
2802 result = check(tree, owntype, TYP, pkind, pt);
2803 }
2804
2805 public void visitTypeDisjoint(JCTypeDisjoint tree) {
2806 List<Type> componentTypes = attribTypes(tree.components, env);
2807 tree.type = result = check(tree, types.lub(componentTypes), TYP, pkind, pt);
2808 }
2809
2810 public void visitTypeParameter(JCTypeParameter tree) {
2811 TypeVar a = (TypeVar)tree.type;
2812 Set<Type> boundSet = new HashSet<Type>();
2813 if (a.bound.isErroneous())
2814 return;
2815 List<Type> bs = types.getBounds(a);
2816 if (tree.bounds.nonEmpty()) {
2817 // accept class or interface or typevar as first bound.
2818 Type b = checkBase(bs.head, tree.bounds.head, env, false, false, false);
2819 boundSet.add(types.erasure(b));
2820 if (b.isErroneous()) {
2821 a.bound = b;
2822 }
2823 else if (b.tag == TYPEVAR) {
2824 // if first bound was a typevar, do not accept further bounds.
2825 if (tree.bounds.tail.nonEmpty()) {
2826 log.error(tree.bounds.tail.head.pos(),
2827 "type.var.may.not.be.followed.by.other.bounds");
2828 log.unrecoverableError = true;
2829 tree.bounds = List.of(tree.bounds.head);
2830 a.bound = bs.head;
2831 }
2832 } else {
2833 // if first bound was a class or interface, accept only interfaces
2834 // as further bounds.
2835 for (JCExpression bound : tree.bounds.tail) {
2836 bs = bs.tail;
2837 Type i = checkBase(bs.head, bound, env, false, true, false);
2838 if (i.isErroneous())
2839 a.bound = i;
2840 else if (i.tag == CLASS)
2841 chk.checkNotRepeated(bound.pos(), types.erasure(i), boundSet);
2842 }
2843 }
2844 }
2845 bs = types.getBounds(a);
2846
2847 // in case of multiple bounds ...
2848 if (bs.length() > 1) {
2849 // ... the variable's bound is a class type flagged COMPOUND
2850 // (see comment for TypeVar.bound).
2851 // In this case, generate a class tree that represents the
2852 // bound class, ...
2853 JCTree extending;
2854 List<JCExpression> implementing;
2855 if ((bs.head.tsym.flags() & INTERFACE) == 0) {
2856 extending = tree.bounds.head;
2857 implementing = tree.bounds.tail;
2858 } else {
2859 extending = null;
2860 implementing = tree.bounds;
2861 }
2862 JCClassDecl cd = make.at(tree.pos).ClassDef(
2863 make.Modifiers(PUBLIC | ABSTRACT),
2864 tree.name, List.<JCTypeParameter>nil(),
2865 extending, implementing, List.<JCTree>nil());
2866
2867 ClassSymbol c = (ClassSymbol)a.getUpperBound().tsym;
2868 assert (c.flags() & COMPOUND) != 0;
2869 cd.sym = c;
2870 c.sourcefile = env.toplevel.sourcefile;
2871
2872 // ... and attribute the bound class
2873 c.flags_field |= UNATTRIBUTED;
2874 Env<AttrContext> cenv = enter.classEnv(cd, env);
2875 enter.typeEnvs.put(c, cenv);
2876 }
2877 }
2878
2879
2880 public void visitWildcard(JCWildcard tree) {
2881 //- System.err.println("visitWildcard("+tree+");");//DEBUG
2882 Type type = (tree.kind.kind == BoundKind.UNBOUND)
2883 ? syms.objectType
2884 : attribType(tree.inner, env);
2885 result = check(tree, new WildcardType(chk.checkRefType(tree.pos(), type),
2886 tree.kind.kind,
2887 syms.boundClass),
2888 TYP, pkind, pt);
2889 }
2890
2891 public void visitAnnotation(JCAnnotation tree) {
2892 log.error(tree.pos(), "annotation.not.valid.for.type", pt);
2893 result = tree.type = syms.errType;
2894 }
2895
2896 public void visitAnnotatedType(JCAnnotatedType tree) {
2897 result = tree.type = attribType(tree.getUnderlyingType(), env);
2898 }
2899
2900 public void visitErroneous(JCErroneous tree) {
2901 if (tree.errs != null)
2902 for (JCTree err : tree.errs)
2903 attribTree(err, env, ERR, pt);
2904 result = tree.type = syms.errType;
2905 }
2906
2907 /** Default visitor method for all other trees.
2908 */
2909 public void visitTree(JCTree tree) {
2910 throw new AssertionError();
2911 }
2912
2913 /** Main method: attribute class definition associated with given class symbol.
2914 * reporting completion failures at the given position.
2915 * @param pos The source position at which completion errors are to be
2916 * reported.
2917 * @param c The class symbol whose definition will be attributed.
2918 */
2919 public void attribClass(DiagnosticPosition pos, ClassSymbol c) {
2920 try {
2921 annotate.flush();
2922 attribClass(c);
2923 } catch (CompletionFailure ex) {
2924 chk.completionError(pos, ex);
2925 }
2926 }
2927
2928 /** Attribute class definition associated with given class symbol.
2929 * @param c The class symbol whose definition will be attributed.
2930 */
2931 void attribClass(ClassSymbol c) throws CompletionFailure {
2932 if (c.type.tag == ERROR) return;
2933
2934 // Check for cycles in the inheritance graph, which can arise from
2935 // ill-formed class files.
2936 chk.checkNonCyclic(null, c.type);
2937
2938 Type st = types.supertype(c.type);
2939 if ((c.flags_field & Flags.COMPOUND) == 0) {
2940 // First, attribute superclass.
2941 if (st.tag == CLASS)
2942 attribClass((ClassSymbol)st.tsym);
2943
2944 // Next attribute owner, if it is a class.
2945 if (c.owner.kind == TYP && c.owner.type.tag == CLASS)
2946 attribClass((ClassSymbol)c.owner);
2947 }
2948
2949 // The previous operations might have attributed the current class
2950 // if there was a cycle. So we test first whether the class is still
2951 // UNATTRIBUTED.
2952 if ((c.flags_field & UNATTRIBUTED) != 0) {
2953 c.flags_field &= ~UNATTRIBUTED;
2954
2955 // Get environment current at the point of class definition.
2956 Env<AttrContext> env = enter.typeEnvs.get(c);
2957
2958 // The info.lint field in the envs stored in enter.typeEnvs is deliberately uninitialized,
2959 // because the annotations were not available at the time the env was created. Therefore,
2960 // we look up the environment chain for the first enclosing environment for which the
2961 // lint value is set. Typically, this is the parent env, but might be further if there
2962 // are any envs created as a result of TypeParameter nodes.
2963 Env<AttrContext> lintEnv = env;
2964 while (lintEnv.info.lint == null)
2965 lintEnv = lintEnv.next;
2966
2967 // Having found the enclosing lint value, we can initialize the lint value for this class
2968 env.info.lint = lintEnv.info.lint.augment(c.attributes_field, c.flags());
2969
2970 Lint prevLint = chk.setLint(env.info.lint);
2971 JavaFileObject prev = log.useSource(c.sourcefile);
2972
2973 try {
2974 // java.lang.Enum may not be subclassed by a non-enum
2975 if (st.tsym == syms.enumSym &&
2976 ((c.flags_field & (Flags.ENUM|Flags.COMPOUND)) == 0))
2977 log.error(env.tree.pos(), "enum.no.subclassing");
2978
2979 // Enums may not be extended by source-level classes
2980 if (st.tsym != null &&
2981 ((st.tsym.flags_field & Flags.ENUM) != 0) &&
2982 ((c.flags_field & (Flags.ENUM | Flags.COMPOUND)) == 0) &&
2983 !target.compilerBootstrap(c)) {
2984 log.error(env.tree.pos(), "enum.types.not.extensible");
2985 }
2986 attribClassBody(env, c);
2987
2988 chk.checkDeprecatedAnnotation(env.tree.pos(), c);
2989 } finally {
2990 log.useSource(prev);
2991 chk.setLint(prevLint);
2992 }
2993
2994 }
2995 }
2996
2997 public void visitImport(JCImport tree) {
2998 // nothing to do
2999 }
3000
3001 /** Finish the attribution of a class. */
3002 private void attribClassBody(Env<AttrContext> env, ClassSymbol c) {
3003 JCClassDecl tree = (JCClassDecl)env.tree;
3004 assert c == tree.sym;
3005
3006 // Validate annotations
3007 chk.validateAnnotations(tree.mods.annotations, c);
3008
3009 // Validate type parameters, supertype and interfaces.
3010 attribBounds(tree.typarams);
3011 if (!c.isAnonymous()) {
3012 //already checked if anonymous
3013 chk.validate(tree.typarams, env);
3014 chk.validate(tree.extending, env);
3015 chk.validate(tree.implementing, env);
3016 }
3017
3018 // If this is a non-abstract class, check that it has no abstract
3019 // methods or unimplemented methods of an implemented interface.
3020 if ((c.flags() & (ABSTRACT | INTERFACE)) == 0) {
3021 if (!relax)
3022 chk.checkAllDefined(tree.pos(), c);
3023 }
3024
3025 if ((c.flags() & ANNOTATION) != 0) {
3026 if (tree.implementing.nonEmpty())
3027 log.error(tree.implementing.head.pos(),
3028 "cant.extend.intf.annotation");
3029 if (tree.typarams.nonEmpty())
3030 log.error(tree.typarams.head.pos(),
3031 "intf.annotation.cant.have.type.params");
3032 } else {
3033 // Check that all extended classes and interfaces
3034 // are compatible (i.e. no two define methods with same arguments
3035 // yet different return types). (JLS 8.4.6.3)
3036 chk.checkCompatibleSupertypes(tree.pos(), c.type);
3037 }
3038
3039 // Check that class does not import the same parameterized interface
3040 // with two different argument lists.
3041 chk.checkClassBounds(tree.pos(), c.type);
3042
3043 tree.type = c.type;
3044
3045 boolean assertsEnabled = false;
3046 assert assertsEnabled = true;
3047 if (assertsEnabled) {
3048 for (List<JCTypeParameter> l = tree.typarams;
3049 l.nonEmpty(); l = l.tail)
3050 assert env.info.scope.lookup(l.head.name).scope != null;
3051 }
3052
3053 // Check that a generic class doesn't extend Throwable
3054 if (!c.type.allparams().isEmpty() && types.isSubtype(c.type, syms.throwableType))
3055 log.error(tree.extending.pos(), "generic.throwable");
3056
3057 // Check that all methods which implement some
3058 // method conform to the method they implement.
3059 chk.checkImplementations(tree);
3060
3061 for (List<JCTree> l = tree.defs; l.nonEmpty(); l = l.tail) {
3062 // Attribute declaration
3063 attribStat(l.head, env);
3064 // Check that declarations in inner classes are not static (JLS 8.1.2)
3065 // Make an exception for static constants.
3066 if (c.owner.kind != PCK &&
3067 ((c.flags() & STATIC) == 0 || c.name == names.empty) &&
3068 (TreeInfo.flags(l.head) & (STATIC | INTERFACE)) != 0) {
3069 Symbol sym = null;
3070 if (l.head.getTag() == JCTree.VARDEF) sym = ((JCVariableDecl) l.head).sym;
3071 if (sym == null ||
3072 sym.kind != VAR ||
3073 ((VarSymbol) sym).getConstValue() == null)
3074 log.error(l.head.pos(), "icls.cant.have.static.decl");
3075 }
3076 }
3077
3078 // Check for cycles among non-initial constructors.
3079 chk.checkCyclicConstructors(tree);
3080
3081 // Check for cycles among annotation elements.
3082 chk.checkNonCyclicElements(tree);
3083
3084 // Check for proper use of serialVersionUID
3085 if (env.info.lint.isEnabled(Lint.LintCategory.SERIAL) &&
3086 isSerializable(c) &&
3087 (c.flags() & Flags.ENUM) == 0 &&
3088 (c.flags() & ABSTRACT) == 0) {
3089 checkSerialVersionUID(tree, c);
3090 }
3091
3092 // Check type annotations applicability rules
3093 validateTypeAnnotations(tree);
3094 }
3095 // where
3096 /** check if a class is a subtype of Serializable, if that is available. */
3097 private boolean isSerializable(ClassSymbol c) {
3098 try {
3099 syms.serializableType.complete();
3100 }
3101 catch (CompletionFailure e) {
3102 return false;
3103 }
3104 return types.isSubtype(c.type, syms.serializableType);
3105 }
3106
3107 /** Check that an appropriate serialVersionUID member is defined. */
3108 private void checkSerialVersionUID(JCClassDecl tree, ClassSymbol c) {
3109
3110 // check for presence of serialVersionUID
3111 Scope.Entry e = c.members().lookup(names.serialVersionUID);
3112 while (e.scope != null && e.sym.kind != VAR) e = e.next();
3113 if (e.scope == null) {
3114 log.warning(tree.pos(), "missing.SVUID", c);
3115 return;
3116 }
3117
3118 // check that it is static final
3119 VarSymbol svuid = (VarSymbol)e.sym;
3120 if ((svuid.flags() & (STATIC | FINAL)) !=
3121 (STATIC | FINAL))
3122 log.warning(TreeInfo.diagnosticPositionFor(svuid, tree), "improper.SVUID", c);
3123
3124 // check that it is long
3125 else if (svuid.type.tag != TypeTags.LONG)
3126 log.warning(TreeInfo.diagnosticPositionFor(svuid, tree), "long.SVUID", c);
3127
3128 // check constant
3129 else if (svuid.getConstValue() == null)
3130 log.warning(TreeInfo.diagnosticPositionFor(svuid, tree), "constant.SVUID", c);
3131 }
3132
3133 private Type capture(Type type) {
3134 return types.capture(type);
3135 }
3136
3137 private void validateTypeAnnotations(JCTree tree) {
3138 tree.accept(typeAnnotationsValidator);
3139 }
3140 //where
3141 private final JCTree.Visitor typeAnnotationsValidator =
3142 new TreeScanner() {
3143 public void visitAnnotation(JCAnnotation tree) {
3144 if (tree instanceof JCTypeAnnotation) {
3145 chk.validateTypeAnnotation((JCTypeAnnotation)tree, false);
3146 }
3147 super.visitAnnotation(tree);
3148 }
3149 public void visitTypeParameter(JCTypeParameter tree) {
3150 chk.validateTypeAnnotations(tree.annotations, true);
3151 // don't call super. skip type annotations
3152 scan(tree.bounds);
3153 }
3154 public void visitMethodDef(JCMethodDecl tree) {
3155 // need to check static methods
3156 if ((tree.sym.flags() & Flags.STATIC) != 0) {
3157 for (JCTypeAnnotation a : tree.receiverAnnotations) {
3158 if (chk.isTypeAnnotation(a, false))
3159 log.error(a.pos(), "annotation.type.not.applicable");
3160 }
3161 }
3162 super.visitMethodDef(tree);
3163 }
3164 };
3165 }