1 /* 2 * Copyright (c) 1999, 2013, Oracle and/or its affiliates. All rights reserved. 3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. 4 * 5 * This code is free software; you can redistribute it and/or modify it 6 * under the terms of the GNU General Public License version 2 only, as 7 * published by the Free Software Foundation. Oracle designates this 8 * particular file as subject to the "Classpath" exception as provided 9 * by Oracle in the LICENSE file that accompanied this code. 10 * 11 * This code is distributed in the hope that it will be useful, but WITHOUT 12 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or 13 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License 14 * version 2 for more details (a copy is included in the LICENSE file that 15 * accompanied this code). 16 * 17 * You should have received a copy of the GNU General Public License version 18 * 2 along with this work; if not, write to the Free Software Foundation, 19 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. 20 * 21 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA 22 * or visit www.oracle.com if you need additional information or have any 23 * questions. 24 */ 25 26 package com.sun.tools.javac.comp; 27 28 import java.util.*; 29 30 import javax.lang.model.element.ElementKind; 31 import javax.lang.model.type.TypeKind; 32 import javax.tools.JavaFileObject; 33 34 import com.sun.source.tree.IdentifierTree; 35 import com.sun.source.tree.MemberReferenceTree.ReferenceMode; 36 import com.sun.source.tree.MemberSelectTree; 37 import com.sun.source.tree.TreeVisitor; 38 import com.sun.source.util.SimpleTreeVisitor; 39 import com.sun.tools.javac.code.*; 40 import com.sun.tools.javac.code.Lint.LintCategory; 41 import com.sun.tools.javac.code.Symbol.*; 42 import com.sun.tools.javac.code.Type.*; 43 import com.sun.tools.javac.comp.Check.CheckContext; 44 import com.sun.tools.javac.comp.DeferredAttr.AttrMode; 45 import com.sun.tools.javac.comp.Infer.InferenceContext; 46 import com.sun.tools.javac.comp.Infer.FreeTypeListener; 47 import com.sun.tools.javac.jvm.*; 48 import com.sun.tools.javac.tree.*; 49 import com.sun.tools.javac.tree.JCTree.*; 50 import com.sun.tools.javac.tree.JCTree.JCPolyExpression.*; 51 import com.sun.tools.javac.util.*; 52 import com.sun.tools.javac.util.JCDiagnostic.DiagnosticPosition; 53 import com.sun.tools.javac.util.List; 54 import static com.sun.tools.javac.code.Flags.*; 55 import static com.sun.tools.javac.code.Flags.ANNOTATION; 56 import static com.sun.tools.javac.code.Flags.BLOCK; 57 import static com.sun.tools.javac.code.Kinds.*; 58 import static com.sun.tools.javac.code.Kinds.ERRONEOUS; 59 import static com.sun.tools.javac.code.TypeTag.*; 60 import static com.sun.tools.javac.code.TypeTag.WILDCARD; 61 import static com.sun.tools.javac.tree.JCTree.Tag.*; 62 63 /** This is the main context-dependent analysis phase in GJC. It 64 * encompasses name resolution, type checking and constant folding as 65 * subtasks. Some subtasks involve auxiliary classes. 66 * @see Check 67 * @see Resolve 68 * @see ConstFold 69 * @see Infer 70 * 71 * <p><b>This is NOT part of any supported API. 72 * If you write code that depends on this, you do so at your own risk. 73 * This code and its internal interfaces are subject to change or 74 * deletion without notice.</b> 75 */ 76 public class Attr extends JCTree.Visitor { 77 protected static final Context.Key<Attr> attrKey = 78 new Context.Key<Attr>(); 79 80 final Names names; 81 final Log log; 82 final Symtab syms; 83 final Resolve rs; 84 final Infer infer; 85 final DeferredAttr deferredAttr; 86 final Check chk; 87 final Flow flow; 88 final MemberEnter memberEnter; 89 final TreeMaker make; 90 final ConstFold cfolder; 91 final Enter enter; 92 final Target target; 93 final Types types; 94 final JCDiagnostic.Factory diags; 95 final Annotate annotate; 96 final DeferredLintHandler deferredLintHandler; 97 98 public static Attr instance(Context context) { 99 Attr instance = context.get(attrKey); 100 if (instance == null) 101 instance = new Attr(context); 102 return instance; 103 } 104 105 protected Attr(Context context) { 106 context.put(attrKey, this); 107 108 names = Names.instance(context); 109 log = Log.instance(context); 110 syms = Symtab.instance(context); 111 rs = Resolve.instance(context); 112 chk = Check.instance(context); 113 flow = Flow.instance(context); 114 memberEnter = MemberEnter.instance(context); 115 make = TreeMaker.instance(context); 116 enter = Enter.instance(context); 117 infer = Infer.instance(context); 118 deferredAttr = DeferredAttr.instance(context); 119 cfolder = ConstFold.instance(context); 120 target = Target.instance(context); 121 types = Types.instance(context); 122 diags = JCDiagnostic.Factory.instance(context); 123 annotate = Annotate.instance(context); 124 deferredLintHandler = DeferredLintHandler.instance(context); 125 126 Options options = Options.instance(context); 127 128 Source source = Source.instance(context); 129 allowGenerics = source.allowGenerics(); 130 allowVarargs = source.allowVarargs(); 131 allowEnums = source.allowEnums(); 132 allowBoxing = source.allowBoxing(); 133 allowCovariantReturns = source.allowCovariantReturns(); 134 allowAnonOuterThis = source.allowAnonOuterThis(); 135 allowStringsInSwitch = source.allowStringsInSwitch(); 136 allowPoly = source.allowPoly(); 137 allowLambda = source.allowLambda(); 138 allowDefaultMethods = source.allowDefaultMethods(); 139 sourceName = source.name; 140 relax = (options.isSet("-retrofit") || 141 options.isSet("-relax")); 142 findDiamonds = options.get("findDiamond") != null && 143 source.allowDiamond(); 144 useBeforeDeclarationWarning = options.isSet("useBeforeDeclarationWarning"); 145 identifyLambdaCandidate = options.getBoolean("identifyLambdaCandidate", false); 146 147 statInfo = new ResultInfo(NIL, Type.noType); 148 varInfo = new ResultInfo(VAR, Type.noType); 149 unknownExprInfo = new ResultInfo(VAL, Type.noType); 150 unknownTypeInfo = new ResultInfo(TYP, Type.noType); 151 unknownTypeExprInfo = new ResultInfo(Kinds.TYP | Kinds.VAL, Type.noType); 152 recoveryInfo = new RecoveryInfo(deferredAttr.emptyDeferredAttrContext); 153 } 154 155 /** Switch: relax some constraints for retrofit mode. 156 */ 157 boolean relax; 158 159 /** Switch: support target-typing inference 160 */ 161 boolean allowPoly; 162 163 /** Switch: support generics? 164 */ 165 boolean allowGenerics; 166 167 /** Switch: allow variable-arity methods. 168 */ 169 boolean allowVarargs; 170 171 /** Switch: support enums? 172 */ 173 boolean allowEnums; 174 175 /** Switch: support boxing and unboxing? 176 */ 177 boolean allowBoxing; 178 179 /** Switch: support covariant result types? 180 */ 181 boolean allowCovariantReturns; 182 183 /** Switch: support lambda expressions ? 184 */ 185 boolean allowLambda; 186 187 /** Switch: support default methods ? 188 */ 189 boolean allowDefaultMethods; 190 191 /** Switch: allow references to surrounding object from anonymous 192 * objects during constructor call? 193 */ 194 boolean allowAnonOuterThis; 195 196 /** Switch: generates a warning if diamond can be safely applied 197 * to a given new expression 198 */ 199 boolean findDiamonds; 200 201 /** 202 * Internally enables/disables diamond finder feature 203 */ 204 static final boolean allowDiamondFinder = true; 205 206 /** 207 * Switch: warn about use of variable before declaration? 208 * RFE: 6425594 209 */ 210 boolean useBeforeDeclarationWarning; 211 212 /** 213 * Switch: generate warnings whenever an anonymous inner class that is convertible 214 * to a lambda expression is found 215 */ 216 boolean identifyLambdaCandidate; 217 218 /** 219 * Switch: allow strings in switch? 220 */ 221 boolean allowStringsInSwitch; 222 223 /** 224 * Switch: name of source level; used for error reporting. 225 */ 226 String sourceName; 227 228 /** Check kind and type of given tree against protokind and prototype. 229 * If check succeeds, store type in tree and return it. 230 * If check fails, store errType in tree and return it. 231 * No checks are performed if the prototype is a method type. 232 * It is not necessary in this case since we know that kind and type 233 * are correct. 234 * 235 * @param tree The tree whose kind and type is checked 236 * @param ownkind The computed kind of the tree 237 * @param resultInfo The expected result of the tree 238 */ 239 Type check(final JCTree tree, final Type found, final int ownkind, final ResultInfo resultInfo) { 240 InferenceContext inferenceContext = resultInfo.checkContext.inferenceContext(); 241 Type owntype = found; 242 if (!owntype.hasTag(ERROR) && !resultInfo.pt.hasTag(METHOD) && !resultInfo.pt.hasTag(FORALL)) { 243 if (inferenceContext.free(found)) { 244 inferenceContext.addFreeTypeListener(List.of(found, resultInfo.pt), new FreeTypeListener() { 245 @Override 246 public void typesInferred(InferenceContext inferenceContext) { 247 ResultInfo pendingResult = 248 resultInfo.dup(inferenceContext.asInstType(resultInfo.pt)); 249 check(tree, inferenceContext.asInstType(found), ownkind, pendingResult); 250 } 251 }); 252 return tree.type = resultInfo.pt; 253 } else { 254 if ((ownkind & ~resultInfo.pkind) == 0) { 255 owntype = resultInfo.check(tree, owntype); 256 } else { 257 log.error(tree.pos(), "unexpected.type", 258 kindNames(resultInfo.pkind), 259 kindName(ownkind)); 260 owntype = types.createErrorType(owntype); 261 } 262 } 263 } 264 tree.type = owntype; 265 return owntype; 266 } 267 268 /** Is given blank final variable assignable, i.e. in a scope where it 269 * may be assigned to even though it is final? 270 * @param v The blank final variable. 271 * @param env The current environment. 272 */ 273 boolean isAssignableAsBlankFinal(VarSymbol v, Env<AttrContext> env) { 274 Symbol owner = owner(env); 275 // owner refers to the innermost variable, method or 276 // initializer block declaration at this point. 277 return 278 v.owner == owner 279 || 280 ((owner.name == names.init || // i.e. we are in a constructor 281 owner.kind == VAR || // i.e. we are in a variable initializer 282 (owner.flags() & BLOCK) != 0) // i.e. we are in an initializer block 283 && 284 v.owner == owner.owner 285 && 286 ((v.flags() & STATIC) != 0) == Resolve.isStatic(env)); 287 } 288 289 /** 290 * Return the innermost enclosing owner symbol in a given attribution context 291 */ 292 Symbol owner(Env<AttrContext> env) { 293 while (true) { 294 switch (env.tree.getTag()) { 295 case VARDEF: 296 //a field can be owner 297 VarSymbol vsym = ((JCVariableDecl)env.tree).sym; 298 if (vsym.owner.kind == TYP) { 299 return vsym; 300 } 301 break; 302 case METHODDEF: 303 //method def is always an owner 304 return ((JCMethodDecl)env.tree).sym; 305 case CLASSDEF: 306 //class def is always an owner 307 return ((JCClassDecl)env.tree).sym; 308 case LAMBDA: 309 //a lambda is an owner - return a fresh synthetic method symbol 310 return new MethodSymbol(0, names.empty, null, syms.methodClass); 311 case BLOCK: 312 //static/instance init blocks are owner 313 Symbol blockSym = env.info.scope.owner; 314 if ((blockSym.flags() & BLOCK) != 0) { 315 return blockSym; 316 } 317 break; 318 case TOPLEVEL: 319 //toplevel is always an owner (for pkge decls) 320 return env.info.scope.owner; 321 } 322 Assert.checkNonNull(env.next); 323 env = env.next; 324 } 325 } 326 327 /** Check that variable can be assigned to. 328 * @param pos The current source code position. 329 * @param v The assigned varaible 330 * @param base If the variable is referred to in a Select, the part 331 * to the left of the `.', null otherwise. 332 * @param env The current environment. 333 */ 334 void checkAssignable(DiagnosticPosition pos, VarSymbol v, JCTree base, Env<AttrContext> env) { 335 if ((v.flags() & FINAL) != 0 && 336 ((v.flags() & HASINIT) != 0 337 || 338 !((base == null || 339 (base.hasTag(IDENT) && TreeInfo.name(base) == names._this)) && 340 isAssignableAsBlankFinal(v, env)))) { 341 if (v.isResourceVariable()) { //TWR resource 342 log.error(pos, "try.resource.may.not.be.assigned", v); 343 } else { 344 log.error(pos, "cant.assign.val.to.final.var", v); 345 } 346 } 347 } 348 349 /** Does tree represent a static reference to an identifier? 350 * It is assumed that tree is either a SELECT or an IDENT. 351 * We have to weed out selects from non-type names here. 352 * @param tree The candidate tree. 353 */ 354 boolean isStaticReference(JCTree tree) { 355 if (tree.hasTag(SELECT)) { 356 Symbol lsym = TreeInfo.symbol(((JCFieldAccess) tree).selected); 357 if (lsym == null || lsym.kind != TYP) { 358 return false; 359 } 360 } 361 return true; 362 } 363 364 /** Is this symbol a type? 365 */ 366 static boolean isType(Symbol sym) { 367 return sym != null && sym.kind == TYP; 368 } 369 370 /** The current `this' symbol. 371 * @param env The current environment. 372 */ 373 Symbol thisSym(DiagnosticPosition pos, Env<AttrContext> env) { 374 return rs.resolveSelf(pos, env, env.enclClass.sym, names._this); 375 } 376 377 /** Attribute a parsed identifier. 378 * @param tree Parsed identifier name 379 * @param topLevel The toplevel to use 380 */ 381 public Symbol attribIdent(JCTree tree, JCCompilationUnit topLevel) { 382 Env<AttrContext> localEnv = enter.topLevelEnv(topLevel); 383 localEnv.enclClass = make.ClassDef(make.Modifiers(0), 384 syms.errSymbol.name, 385 null, null, null, null); 386 localEnv.enclClass.sym = syms.errSymbol; 387 return tree.accept(identAttributer, localEnv); 388 } 389 // where 390 private TreeVisitor<Symbol,Env<AttrContext>> identAttributer = new IdentAttributer(); 391 private class IdentAttributer extends SimpleTreeVisitor<Symbol,Env<AttrContext>> { 392 @Override 393 public Symbol visitMemberSelect(MemberSelectTree node, Env<AttrContext> env) { 394 Symbol site = visit(node.getExpression(), env); 395 if (site.kind == ERR) 396 return site; 397 Name name = (Name)node.getIdentifier(); 398 if (site.kind == PCK) { 399 env.toplevel.packge = (PackageSymbol)site; 400 return rs.findIdentInPackage(env, (TypeSymbol)site, name, TYP | PCK); 401 } else { 402 env.enclClass.sym = (ClassSymbol)site; 403 return rs.findMemberType(env, site.asType(), name, (TypeSymbol)site); 404 } 405 } 406 407 @Override 408 public Symbol visitIdentifier(IdentifierTree node, Env<AttrContext> env) { 409 return rs.findIdent(env, (Name)node.getName(), TYP | PCK); 410 } 411 } 412 413 public Type coerce(Type etype, Type ttype) { 414 return cfolder.coerce(etype, ttype); 415 } 416 417 public Type attribType(JCTree node, TypeSymbol sym) { 418 Env<AttrContext> env = enter.typeEnvs.get(sym); 419 Env<AttrContext> localEnv = env.dup(node, env.info.dup()); 420 return attribTree(node, localEnv, unknownTypeInfo); 421 } 422 423 public Type attribImportQualifier(JCImport tree, Env<AttrContext> env) { 424 // Attribute qualifying package or class. 425 JCFieldAccess s = (JCFieldAccess)tree.qualid; 426 return attribTree(s.selected, 427 env, 428 new ResultInfo(tree.staticImport ? TYP : (TYP | PCK), 429 Type.noType)); 430 } 431 432 public Env<AttrContext> attribExprToTree(JCTree expr, Env<AttrContext> env, JCTree tree) { 433 breakTree = tree; 434 JavaFileObject prev = log.useSource(env.toplevel.sourcefile); 435 try { 436 attribExpr(expr, env); 437 } catch (BreakAttr b) { 438 return b.env; 439 } catch (AssertionError ae) { 440 if (ae.getCause() instanceof BreakAttr) { 441 return ((BreakAttr)(ae.getCause())).env; 442 } else { 443 throw ae; 444 } 445 } finally { 446 breakTree = null; 447 log.useSource(prev); 448 } 449 return env; 450 } 451 452 public Env<AttrContext> attribStatToTree(JCTree stmt, Env<AttrContext> env, JCTree tree) { 453 breakTree = tree; 454 JavaFileObject prev = log.useSource(env.toplevel.sourcefile); 455 try { 456 attribStat(stmt, env); 457 } catch (BreakAttr b) { 458 return b.env; 459 } catch (AssertionError ae) { 460 if (ae.getCause() instanceof BreakAttr) { 461 return ((BreakAttr)(ae.getCause())).env; 462 } else { 463 throw ae; 464 } 465 } finally { 466 breakTree = null; 467 log.useSource(prev); 468 } 469 return env; 470 } 471 472 private JCTree breakTree = null; 473 474 private static class BreakAttr extends RuntimeException { 475 static final long serialVersionUID = -6924771130405446405L; 476 private Env<AttrContext> env; 477 private BreakAttr(Env<AttrContext> env) { 478 this.env = copyEnv(env); 479 } 480 481 private Env<AttrContext> copyEnv(Env<AttrContext> env) { 482 Env<AttrContext> newEnv = 483 env.dup(env.tree, env.info.dup(copyScope(env.info.scope))); 484 if (newEnv.outer != null) { 485 newEnv.outer = copyEnv(newEnv.outer); 486 } 487 return newEnv; 488 } 489 490 private Scope copyScope(Scope sc) { 491 Scope newScope = new Scope(sc.owner); 492 List<Symbol> elemsList = List.nil(); 493 while (sc != null) { 494 for (Scope.Entry e = sc.elems ; e != null ; e = e.sibling) { 495 elemsList = elemsList.prepend(e.sym); 496 } 497 sc = sc.next; 498 } 499 for (Symbol s : elemsList) { 500 newScope.enter(s); 501 } 502 return newScope; 503 } 504 } 505 506 class ResultInfo { 507 final int pkind; 508 final Type pt; 509 final CheckContext checkContext; 510 511 ResultInfo(int pkind, Type pt) { 512 this(pkind, pt, chk.basicHandler); 513 } 514 515 protected ResultInfo(int pkind, Type pt, CheckContext checkContext) { 516 this.pkind = pkind; 517 this.pt = pt; 518 this.checkContext = checkContext; 519 } 520 521 protected Type check(final DiagnosticPosition pos, final Type found) { 522 return chk.checkType(pos, found, pt, checkContext); 523 } 524 525 protected ResultInfo dup(Type newPt) { 526 return new ResultInfo(pkind, newPt, checkContext); 527 } 528 529 protected ResultInfo dup(CheckContext newContext) { 530 return new ResultInfo(pkind, pt, newContext); 531 } 532 } 533 534 class RecoveryInfo extends ResultInfo { 535 536 public RecoveryInfo(final DeferredAttr.DeferredAttrContext deferredAttrContext) { 537 super(Kinds.VAL, Type.recoveryType, new Check.NestedCheckContext(chk.basicHandler) { 538 @Override 539 public DeferredAttr.DeferredAttrContext deferredAttrContext() { 540 return deferredAttrContext; 541 } 542 @Override 543 public boolean compatible(Type found, Type req, Warner warn) { 544 return true; 545 } 546 @Override 547 public void report(DiagnosticPosition pos, JCDiagnostic details) { 548 chk.basicHandler.report(pos, details); 549 } 550 }); 551 } 552 553 @Override 554 protected Type check(DiagnosticPosition pos, Type found) { 555 return chk.checkNonVoid(pos, super.check(pos, found)); 556 } 557 } 558 559 final ResultInfo statInfo; 560 final ResultInfo varInfo; 561 final ResultInfo unknownExprInfo; 562 final ResultInfo unknownTypeInfo; 563 final ResultInfo unknownTypeExprInfo; 564 final ResultInfo recoveryInfo; 565 566 Type pt() { 567 return resultInfo.pt; 568 } 569 570 int pkind() { 571 return resultInfo.pkind; 572 } 573 574 /* ************************************************************************ 575 * Visitor methods 576 *************************************************************************/ 577 578 /** Visitor argument: the current environment. 579 */ 580 Env<AttrContext> env; 581 582 /** Visitor argument: the currently expected attribution result. 583 */ 584 ResultInfo resultInfo; 585 586 /** Visitor result: the computed type. 587 */ 588 Type result; 589 590 /** Visitor method: attribute a tree, catching any completion failure 591 * exceptions. Return the tree's type. 592 * 593 * @param tree The tree to be visited. 594 * @param env The environment visitor argument. 595 * @param resultInfo The result info visitor argument. 596 */ 597 Type attribTree(JCTree tree, Env<AttrContext> env, ResultInfo resultInfo) { 598 Env<AttrContext> prevEnv = this.env; 599 ResultInfo prevResult = this.resultInfo; 600 try { 601 this.env = env; 602 this.resultInfo = resultInfo; 603 tree.accept(this); 604 if (tree == breakTree && 605 resultInfo.checkContext.deferredAttrContext().mode == AttrMode.CHECK) { 606 throw new BreakAttr(env); 607 } 608 return result; 609 } catch (CompletionFailure ex) { 610 tree.type = syms.errType; 611 return chk.completionError(tree.pos(), ex); 612 } finally { 613 this.env = prevEnv; 614 this.resultInfo = prevResult; 615 } 616 } 617 618 /** Derived visitor method: attribute an expression tree. 619 */ 620 public Type attribExpr(JCTree tree, Env<AttrContext> env, Type pt) { 621 return attribTree(tree, env, new ResultInfo(VAL, !pt.hasTag(ERROR) ? pt : Type.noType)); 622 } 623 624 /** Derived visitor method: attribute an expression tree with 625 * no constraints on the computed type. 626 */ 627 public Type attribExpr(JCTree tree, Env<AttrContext> env) { 628 return attribTree(tree, env, unknownExprInfo); 629 } 630 631 /** Derived visitor method: attribute a type tree. 632 */ 633 public Type attribType(JCTree tree, Env<AttrContext> env) { 634 Type result = attribType(tree, env, Type.noType); 635 return result; 636 } 637 638 /** Derived visitor method: attribute a type tree. 639 */ 640 Type attribType(JCTree tree, Env<AttrContext> env, Type pt) { 641 Type result = attribTree(tree, env, new ResultInfo(TYP, pt)); 642 return result; 643 } 644 645 /** Derived visitor method: attribute a statement or definition tree. 646 */ 647 public Type attribStat(JCTree tree, Env<AttrContext> env) { 648 return attribTree(tree, env, statInfo); 649 } 650 651 /** Attribute a list of expressions, returning a list of types. 652 */ 653 List<Type> attribExprs(List<JCExpression> trees, Env<AttrContext> env, Type pt) { 654 ListBuffer<Type> ts = new ListBuffer<Type>(); 655 for (List<JCExpression> l = trees; l.nonEmpty(); l = l.tail) 656 ts.append(attribExpr(l.head, env, pt)); 657 return ts.toList(); 658 } 659 660 /** Attribute a list of statements, returning nothing. 661 */ 662 <T extends JCTree> void attribStats(List<T> trees, Env<AttrContext> env) { 663 for (List<T> l = trees; l.nonEmpty(); l = l.tail) 664 attribStat(l.head, env); 665 } 666 667 /** Attribute the arguments in a method call, returning a list of types. 668 */ 669 List<Type> attribArgs(List<JCExpression> trees, Env<AttrContext> env) { 670 ListBuffer<Type> argtypes = new ListBuffer<Type>(); 671 for (JCExpression arg : trees) { 672 Type argtype = allowPoly && deferredAttr.isDeferred(env, arg) ? 673 deferredAttr.new DeferredType(arg, env) : 674 chk.checkNonVoid(arg, attribExpr(arg, env, Infer.anyPoly)); 675 argtypes.append(argtype); 676 } 677 return argtypes.toList(); 678 } 679 680 /** Attribute a type argument list, returning a list of types. 681 * Caller is responsible for calling checkRefTypes. 682 */ 683 List<Type> attribAnyTypes(List<JCExpression> trees, Env<AttrContext> env) { 684 ListBuffer<Type> argtypes = new ListBuffer<Type>(); 685 for (List<JCExpression> l = trees; l.nonEmpty(); l = l.tail) 686 argtypes.append(attribType(l.head, env)); 687 return argtypes.toList(); 688 } 689 690 /** Attribute a type argument list, returning a list of types. 691 * Check that all the types are references. 692 */ 693 List<Type> attribTypes(List<JCExpression> trees, Env<AttrContext> env) { 694 List<Type> types = attribAnyTypes(trees, env); 695 return chk.checkRefTypes(trees, types); 696 } 697 698 /** 699 * Attribute type variables (of generic classes or methods). 700 * Compound types are attributed later in attribBounds. 701 * @param typarams the type variables to enter 702 * @param env the current environment 703 */ 704 void attribTypeVariables(List<JCTypeParameter> typarams, Env<AttrContext> env) { 705 for (JCTypeParameter tvar : typarams) { 706 TypeVar a = (TypeVar)tvar.type; 707 a.tsym.flags_field |= UNATTRIBUTED; 708 a.bound = Type.noType; 709 if (!tvar.bounds.isEmpty()) { 710 List<Type> bounds = List.of(attribType(tvar.bounds.head, env)); 711 for (JCExpression bound : tvar.bounds.tail) 712 bounds = bounds.prepend(attribType(bound, env)); 713 types.setBounds(a, bounds.reverse()); 714 } else { 715 // if no bounds are given, assume a single bound of 716 // java.lang.Object. 717 types.setBounds(a, List.of(syms.objectType)); 718 } 719 a.tsym.flags_field &= ~UNATTRIBUTED; 720 } 721 for (JCTypeParameter tvar : typarams) { 722 chk.checkNonCyclic(tvar.pos(), (TypeVar)tvar.type); 723 } 724 } 725 726 /** 727 * Attribute the type references in a list of annotations. 728 */ 729 void attribAnnotationTypes(List<JCAnnotation> annotations, 730 Env<AttrContext> env) { 731 for (List<JCAnnotation> al = annotations; al.nonEmpty(); al = al.tail) { 732 JCAnnotation a = al.head; 733 attribType(a.annotationType, env); 734 } 735 } 736 737 /** 738 * Attribute a "lazy constant value". 739 * @param env The env for the const value 740 * @param initializer The initializer for the const value 741 * @param type The expected type, or null 742 * @see VarSymbol#setLazyConstValue 743 */ 744 public Object attribLazyConstantValue(Env<AttrContext> env, 745 JCTree.JCExpression initializer, 746 Type type) { 747 748 // in case no lint value has been set up for this env, scan up 749 // env stack looking for smallest enclosing env for which it is set. 750 Env<AttrContext> lintEnv = env; 751 while (lintEnv.info.lint == null) 752 lintEnv = lintEnv.next; 753 754 // Having found the enclosing lint value, we can initialize the lint value for this class 755 // ... but ... 756 // There's a problem with evaluating annotations in the right order, such that 757 // env.info.enclVar.attributes_field might not yet have been evaluated, and so might be 758 // null. In that case, calling augment will throw an NPE. To avoid this, for now we 759 // revert to the jdk 6 behavior and ignore the (unevaluated) attributes. 760 if (env.info.enclVar.annotations.pendingCompletion()) { 761 env.info.lint = lintEnv.info.lint; 762 } else { 763 env.info.lint = lintEnv.info.lint.augment(env.info.enclVar.annotations, 764 env.info.enclVar.flags()); 765 } 766 767 Lint prevLint = chk.setLint(env.info.lint); 768 JavaFileObject prevSource = log.useSource(env.toplevel.sourcefile); 769 770 try { 771 // Use null as symbol to not attach the type annotation to any symbol. 772 // The initializer will later also be visited and then we'll attach 773 // to the symbol. 774 // This prevents having multiple type annotations, just because of 775 // lazy constant value evaluation. 776 memberEnter.typeAnnotate(initializer, env, null); 777 annotate.flush(); 778 Type itype = attribExpr(initializer, env, type); 779 if (itype.constValue() != null) 780 return coerce(itype, type).constValue(); 781 else 782 return null; 783 } finally { 784 env.info.lint = prevLint; 785 log.useSource(prevSource); 786 } 787 } 788 789 /** Attribute type reference in an `extends' or `implements' clause. 790 * Supertypes of anonymous inner classes are usually already attributed. 791 * 792 * @param tree The tree making up the type reference. 793 * @param env The environment current at the reference. 794 * @param classExpected true if only a class is expected here. 795 * @param interfaceExpected true if only an interface is expected here. 796 */ 797 Type attribBase(JCTree tree, 798 Env<AttrContext> env, 799 boolean classExpected, 800 boolean interfaceExpected, 801 boolean checkExtensible) { 802 Type t = tree.type != null ? 803 tree.type : 804 attribType(tree, env); 805 return checkBase(t, tree, env, classExpected, interfaceExpected, checkExtensible); 806 } 807 Type checkBase(Type t, 808 JCTree tree, 809 Env<AttrContext> env, 810 boolean classExpected, 811 boolean interfaceExpected, 812 boolean checkExtensible) { 813 if (t.isErroneous()) 814 return t; 815 if (t.hasTag(TYPEVAR) && !classExpected && !interfaceExpected) { 816 // check that type variable is already visible 817 if (t.getUpperBound() == null) { 818 log.error(tree.pos(), "illegal.forward.ref"); 819 return types.createErrorType(t); 820 } 821 } else { 822 t = chk.checkClassType(tree.pos(), t, checkExtensible|!allowGenerics); 823 } 824 if (interfaceExpected && (t.tsym.flags() & INTERFACE) == 0) { 825 log.error(tree.pos(), "intf.expected.here"); 826 // return errType is necessary since otherwise there might 827 // be undetected cycles which cause attribution to loop 828 return types.createErrorType(t); 829 } else if (checkExtensible && 830 classExpected && 831 (t.tsym.flags() & INTERFACE) != 0) { 832 log.error(tree.pos(), "no.intf.expected.here"); 833 return types.createErrorType(t); 834 } 835 if (checkExtensible && 836 ((t.tsym.flags() & FINAL) != 0)) { 837 log.error(tree.pos(), 838 "cant.inherit.from.final", t.tsym); 839 } 840 chk.checkNonCyclic(tree.pos(), t); 841 return t; 842 } 843 844 Type attribIdentAsEnumType(Env<AttrContext> env, JCIdent id) { 845 Assert.check((env.enclClass.sym.flags() & ENUM) != 0); 846 id.type = env.info.scope.owner.type; 847 id.sym = env.info.scope.owner; 848 return id.type; 849 } 850 851 public void visitClassDef(JCClassDecl tree) { 852 // Local classes have not been entered yet, so we need to do it now: 853 if ((env.info.scope.owner.kind & (VAR | MTH)) != 0) 854 enter.classEnter(tree, env); 855 856 ClassSymbol c = tree.sym; 857 if (c == null) { 858 // exit in case something drastic went wrong during enter. 859 result = null; 860 } else { 861 // make sure class has been completed: 862 c.complete(); 863 864 // If this class appears as an anonymous class 865 // in a superclass constructor call where 866 // no explicit outer instance is given, 867 // disable implicit outer instance from being passed. 868 // (This would be an illegal access to "this before super"). 869 if (env.info.isSelfCall && 870 env.tree.hasTag(NEWCLASS) && 871 ((JCNewClass) env.tree).encl == null) 872 { 873 c.flags_field |= NOOUTERTHIS; 874 } 875 attribClass(tree.pos(), c); 876 result = tree.type = c.type; 877 } 878 } 879 880 public void visitMethodDef(JCMethodDecl tree) { 881 MethodSymbol m = tree.sym; 882 boolean isDefaultMethod = (m.flags() & DEFAULT) != 0; 883 884 Lint lint = env.info.lint.augment(m.annotations, m.flags()); 885 Lint prevLint = chk.setLint(lint); 886 MethodSymbol prevMethod = chk.setMethod(m); 887 try { 888 deferredLintHandler.flush(tree.pos()); 889 chk.checkDeprecatedAnnotation(tree.pos(), m); 890 891 892 // Create a new environment with local scope 893 // for attributing the method. 894 Env<AttrContext> localEnv = memberEnter.methodEnv(tree, env); 895 localEnv.info.lint = lint; 896 897 attribStats(tree.typarams, localEnv); 898 899 // If we override any other methods, check that we do so properly. 900 // JLS ??? 901 if (m.isStatic()) { 902 chk.checkHideClashes(tree.pos(), env.enclClass.type, m); 903 } else { 904 chk.checkOverrideClashes(tree.pos(), env.enclClass.type, m); 905 } 906 chk.checkOverride(tree, m); 907 908 if (isDefaultMethod && types.overridesObjectMethod(m.enclClass(), m)) { 909 log.error(tree, "default.overrides.object.member", m.name, Kinds.kindName(m.location()), m.location()); 910 } 911 912 // Enter all type parameters into the local method scope. 913 for (List<JCTypeParameter> l = tree.typarams; l.nonEmpty(); l = l.tail) 914 localEnv.info.scope.enterIfAbsent(l.head.type.tsym); 915 916 ClassSymbol owner = env.enclClass.sym; 917 if ((owner.flags() & ANNOTATION) != 0 && 918 tree.params.nonEmpty()) 919 log.error(tree.params.head.pos(), 920 "intf.annotation.members.cant.have.params"); 921 922 // Attribute all value parameters. 923 for (List<JCVariableDecl> l = tree.params; l.nonEmpty(); l = l.tail) { 924 attribStat(l.head, localEnv); 925 } 926 927 chk.checkVarargsMethodDecl(localEnv, tree); 928 929 // Check that type parameters are well-formed. 930 chk.validate(tree.typarams, localEnv); 931 932 // Check that result type is well-formed. 933 chk.validate(tree.restype, localEnv); 934 935 // Check that receiver type is well-formed. 936 if (tree.recvparam != null) { 937 // Use a new environment to check the receiver parameter. 938 // Otherwise I get "might not have been initialized" errors. 939 // Is there a better way? 940 Env<AttrContext> newEnv = memberEnter.methodEnv(tree, env); 941 attribType(tree.recvparam, newEnv); 942 chk.validate(tree.recvparam, newEnv); 943 } 944 945 // annotation method checks 946 if ((owner.flags() & ANNOTATION) != 0) { 947 // annotation method cannot have throws clause 948 if (tree.thrown.nonEmpty()) { 949 log.error(tree.thrown.head.pos(), 950 "throws.not.allowed.in.intf.annotation"); 951 } 952 // annotation method cannot declare type-parameters 953 if (tree.typarams.nonEmpty()) { 954 log.error(tree.typarams.head.pos(), 955 "intf.annotation.members.cant.have.type.params"); 956 } 957 // validate annotation method's return type (could be an annotation type) 958 chk.validateAnnotationType(tree.restype); 959 // ensure that annotation method does not clash with members of Object/Annotation 960 chk.validateAnnotationMethod(tree.pos(), m); 961 962 if (tree.defaultValue != null) { 963 // if default value is an annotation, check it is a well-formed 964 // annotation value (e.g. no duplicate values, no missing values, etc.) 965 chk.validateAnnotationTree(tree.defaultValue); 966 } 967 } 968 969 for (List<JCExpression> l = tree.thrown; l.nonEmpty(); l = l.tail) 970 chk.checkType(l.head.pos(), l.head.type, syms.throwableType); 971 972 if (tree.body == null) { 973 // Empty bodies are only allowed for 974 // abstract, native, or interface methods, or for methods 975 // in a retrofit signature class. 976 if (isDefaultMethod || (tree.sym.flags() & (ABSTRACT | NATIVE)) == 0 && 977 !relax) 978 log.error(tree.pos(), "missing.meth.body.or.decl.abstract"); 979 if (tree.defaultValue != null) { 980 if ((owner.flags() & ANNOTATION) == 0) 981 log.error(tree.pos(), 982 "default.allowed.in.intf.annotation.member"); 983 } 984 } else if ((tree.sym.flags() & ABSTRACT) != 0 && !isDefaultMethod) { 985 if ((owner.flags() & INTERFACE) != 0) { 986 log.error(tree.body.pos(), "intf.meth.cant.have.body"); 987 } else { 988 log.error(tree.pos(), "abstract.meth.cant.have.body"); 989 } 990 } else if ((tree.mods.flags & NATIVE) != 0) { 991 log.error(tree.pos(), "native.meth.cant.have.body"); 992 } else { 993 // Add an implicit super() call unless an explicit call to 994 // super(...) or this(...) is given 995 // or we are compiling class java.lang.Object. 996 if (tree.name == names.init && owner.type != syms.objectType) { 997 JCBlock body = tree.body; 998 if (body.stats.isEmpty() || 999 !TreeInfo.isSelfCall(body.stats.head)) { 1000 body.stats = body.stats. 1001 prepend(memberEnter.SuperCall(make.at(body.pos), 1002 List.<Type>nil(), 1003 List.<JCVariableDecl>nil(), 1004 false)); 1005 } else if ((env.enclClass.sym.flags() & ENUM) != 0 && 1006 (tree.mods.flags & GENERATEDCONSTR) == 0 && 1007 TreeInfo.isSuperCall(body.stats.head)) { 1008 // enum constructors are not allowed to call super 1009 // directly, so make sure there aren't any super calls 1010 // in enum constructors, except in the compiler 1011 // generated one. 1012 log.error(tree.body.stats.head.pos(), 1013 "call.to.super.not.allowed.in.enum.ctor", 1014 env.enclClass.sym); 1015 } 1016 } 1017 1018 // Attribute all type annotations in the body 1019 memberEnter.typeAnnotate(tree.body, localEnv, m); 1020 annotate.flush(); 1021 1022 // Attribute method body. 1023 attribStat(tree.body, localEnv); 1024 } 1025 1026 localEnv.info.scope.leave(); 1027 result = tree.type = m.type; 1028 chk.validateAnnotations(tree.mods.annotations, m); 1029 } 1030 finally { 1031 chk.setLint(prevLint); 1032 chk.setMethod(prevMethod); 1033 } 1034 } 1035 1036 public void visitVarDef(JCVariableDecl tree) { 1037 // Local variables have not been entered yet, so we need to do it now: 1038 if (env.info.scope.owner.kind == MTH) { 1039 if (tree.sym != null) { 1040 // parameters have already been entered 1041 env.info.scope.enter(tree.sym); 1042 } else { 1043 memberEnter.memberEnter(tree, env); 1044 annotate.flush(); 1045 } 1046 } else { 1047 if (tree.init != null) { 1048 // Field initializer expression need to be entered. 1049 memberEnter.typeAnnotate(tree.init, env, tree.sym); 1050 annotate.flush(); 1051 } 1052 } 1053 1054 VarSymbol v = tree.sym; 1055 Lint lint = env.info.lint.augment(v.annotations, v.flags()); 1056 Lint prevLint = chk.setLint(lint); 1057 1058 // Check that the variable's declared type is well-formed. 1059 boolean isImplicitLambdaParameter = env.tree.hasTag(LAMBDA) && 1060 ((JCLambda)env.tree).paramKind == JCLambda.ParameterKind.IMPLICIT && 1061 (tree.sym.flags() & PARAMETER) != 0; 1062 chk.validate(tree.vartype, env, !isImplicitLambdaParameter); 1063 deferredLintHandler.flush(tree.pos()); 1064 1065 try { 1066 chk.checkDeprecatedAnnotation(tree.pos(), v); 1067 1068 if (tree.init != null) { 1069 if ((v.flags_field & FINAL) != 0 && 1070 !tree.init.hasTag(NEWCLASS) && 1071 !tree.init.hasTag(LAMBDA) && 1072 !tree.init.hasTag(REFERENCE)) { 1073 // In this case, `v' is final. Ensure that it's initializer is 1074 // evaluated. 1075 v.getConstValue(); // ensure initializer is evaluated 1076 } else { 1077 // Attribute initializer in a new environment 1078 // with the declared variable as owner. 1079 // Check that initializer conforms to variable's declared type. 1080 Env<AttrContext> initEnv = memberEnter.initEnv(tree, env); 1081 initEnv.info.lint = lint; 1082 // In order to catch self-references, we set the variable's 1083 // declaration position to maximal possible value, effectively 1084 // marking the variable as undefined. 1085 initEnv.info.enclVar = v; 1086 attribExpr(tree.init, initEnv, v.type); 1087 } 1088 } 1089 result = tree.type = v.type; 1090 chk.validateAnnotations(tree.mods.annotations, v); 1091 } 1092 finally { 1093 chk.setLint(prevLint); 1094 } 1095 } 1096 1097 public void visitSkip(JCSkip tree) { 1098 result = null; 1099 } 1100 1101 public void visitBlock(JCBlock tree) { 1102 if (env.info.scope.owner.kind == TYP) { 1103 // Block is a static or instance initializer; 1104 // let the owner of the environment be a freshly 1105 // created BLOCK-method. 1106 Env<AttrContext> localEnv = 1107 env.dup(tree, env.info.dup(env.info.scope.dupUnshared())); 1108 localEnv.info.scope.owner = 1109 new MethodSymbol(tree.flags | BLOCK | 1110 env.info.scope.owner.flags() & STRICTFP, names.empty, null, 1111 env.info.scope.owner); 1112 if ((tree.flags & STATIC) != 0) localEnv.info.staticLevel++; 1113 1114 // Attribute all type annotations in the block 1115 memberEnter.typeAnnotate(tree, localEnv, localEnv.info.scope.owner); 1116 annotate.flush(); 1117 1118 { 1119 // Store init and clinit type annotations with the ClassSymbol 1120 // to allow output in Gen.normalizeDefs. 1121 ClassSymbol cs = (ClassSymbol)env.info.scope.owner; 1122 List<Attribute.TypeCompound> tas = localEnv.info.scope.owner.getRawTypeAttributes(); 1123 if ((tree.flags & STATIC) != 0) { 1124 cs.annotations.appendClassInitTypeAttributes(tas); 1125 } else { 1126 cs.annotations.appendInitTypeAttributes(tas); 1127 } 1128 } 1129 1130 attribStats(tree.stats, localEnv); 1131 } else { 1132 // Create a new local environment with a local scope. 1133 Env<AttrContext> localEnv = 1134 env.dup(tree, env.info.dup(env.info.scope.dup())); 1135 try { 1136 attribStats(tree.stats, localEnv); 1137 } finally { 1138 localEnv.info.scope.leave(); 1139 } 1140 } 1141 result = null; 1142 } 1143 1144 public void visitDoLoop(JCDoWhileLoop tree) { 1145 attribStat(tree.body, env.dup(tree)); 1146 attribExpr(tree.cond, env, syms.booleanType); 1147 result = null; 1148 } 1149 1150 public void visitWhileLoop(JCWhileLoop tree) { 1151 attribExpr(tree.cond, env, syms.booleanType); 1152 attribStat(tree.body, env.dup(tree)); 1153 result = null; 1154 } 1155 1156 public void visitForLoop(JCForLoop tree) { 1157 Env<AttrContext> loopEnv = 1158 env.dup(env.tree, env.info.dup(env.info.scope.dup())); 1159 try { 1160 attribStats(tree.init, loopEnv); 1161 if (tree.cond != null) attribExpr(tree.cond, loopEnv, syms.booleanType); 1162 loopEnv.tree = tree; // before, we were not in loop! 1163 attribStats(tree.step, loopEnv); 1164 attribStat(tree.body, loopEnv); 1165 result = null; 1166 } 1167 finally { 1168 loopEnv.info.scope.leave(); 1169 } 1170 } 1171 1172 public void visitForeachLoop(JCEnhancedForLoop tree) { 1173 Env<AttrContext> loopEnv = 1174 env.dup(env.tree, env.info.dup(env.info.scope.dup())); 1175 try { 1176 attribStat(tree.var, loopEnv); 1177 Type exprType = types.upperBound(attribExpr(tree.expr, loopEnv)); 1178 chk.checkNonVoid(tree.pos(), exprType); 1179 Type elemtype = types.elemtype(exprType); // perhaps expr is an array? 1180 if (elemtype == null) { 1181 // or perhaps expr implements Iterable<T>? 1182 Type base = types.asSuper(exprType, syms.iterableType.tsym); 1183 if (base == null) { 1184 log.error(tree.expr.pos(), 1185 "foreach.not.applicable.to.type", 1186 exprType, 1187 diags.fragment("type.req.array.or.iterable")); 1188 elemtype = types.createErrorType(exprType); 1189 } else { 1190 List<Type> iterableParams = base.allparams(); 1191 elemtype = iterableParams.isEmpty() 1192 ? syms.objectType 1193 : types.upperBound(iterableParams.head); 1194 } 1195 } 1196 chk.checkType(tree.expr.pos(), elemtype, tree.var.sym.type); 1197 loopEnv.tree = tree; // before, we were not in loop! 1198 attribStat(tree.body, loopEnv); 1199 result = null; 1200 } 1201 finally { 1202 loopEnv.info.scope.leave(); 1203 } 1204 } 1205 1206 public void visitLabelled(JCLabeledStatement tree) { 1207 // Check that label is not used in an enclosing statement 1208 Env<AttrContext> env1 = env; 1209 while (env1 != null && !env1.tree.hasTag(CLASSDEF)) { 1210 if (env1.tree.hasTag(LABELLED) && 1211 ((JCLabeledStatement) env1.tree).label == tree.label) { 1212 log.error(tree.pos(), "label.already.in.use", 1213 tree.label); 1214 break; 1215 } 1216 env1 = env1.next; 1217 } 1218 1219 attribStat(tree.body, env.dup(tree)); 1220 result = null; 1221 } 1222 1223 public void visitSwitch(JCSwitch tree) { 1224 Type seltype = attribExpr(tree.selector, env); 1225 1226 Env<AttrContext> switchEnv = 1227 env.dup(tree, env.info.dup(env.info.scope.dup())); 1228 1229 try { 1230 1231 boolean enumSwitch = 1232 allowEnums && 1233 (seltype.tsym.flags() & Flags.ENUM) != 0; 1234 boolean stringSwitch = false; 1235 if (types.isSameType(seltype, syms.stringType)) { 1236 if (allowStringsInSwitch) { 1237 stringSwitch = true; 1238 } else { 1239 log.error(tree.selector.pos(), "string.switch.not.supported.in.source", sourceName); 1240 } 1241 } 1242 if (!enumSwitch && !stringSwitch) 1243 seltype = chk.checkType(tree.selector.pos(), seltype, syms.intType); 1244 1245 // Attribute all cases and 1246 // check that there are no duplicate case labels or default clauses. 1247 Set<Object> labels = new HashSet<Object>(); // The set of case labels. 1248 boolean hasDefault = false; // Is there a default label? 1249 for (List<JCCase> l = tree.cases; l.nonEmpty(); l = l.tail) { 1250 JCCase c = l.head; 1251 Env<AttrContext> caseEnv = 1252 switchEnv.dup(c, env.info.dup(switchEnv.info.scope.dup())); 1253 try { 1254 if (c.pat != null) { 1255 if (enumSwitch) { 1256 Symbol sym = enumConstant(c.pat, seltype); 1257 if (sym == null) { 1258 log.error(c.pat.pos(), "enum.label.must.be.unqualified.enum"); 1259 } else if (!labels.add(sym)) { 1260 log.error(c.pos(), "duplicate.case.label"); 1261 } 1262 } else { 1263 Type pattype = attribExpr(c.pat, switchEnv, seltype); 1264 if (!pattype.hasTag(ERROR)) { 1265 if (pattype.constValue() == null) { 1266 log.error(c.pat.pos(), 1267 (stringSwitch ? "string.const.req" : "const.expr.req")); 1268 } else if (labels.contains(pattype.constValue())) { 1269 log.error(c.pos(), "duplicate.case.label"); 1270 } else { 1271 labels.add(pattype.constValue()); 1272 } 1273 } 1274 } 1275 } else if (hasDefault) { 1276 log.error(c.pos(), "duplicate.default.label"); 1277 } else { 1278 hasDefault = true; 1279 } 1280 attribStats(c.stats, caseEnv); 1281 } finally { 1282 caseEnv.info.scope.leave(); 1283 addVars(c.stats, switchEnv.info.scope); 1284 } 1285 } 1286 1287 result = null; 1288 } 1289 finally { 1290 switchEnv.info.scope.leave(); 1291 } 1292 } 1293 // where 1294 /** Add any variables defined in stats to the switch scope. */ 1295 private static void addVars(List<JCStatement> stats, Scope switchScope) { 1296 for (;stats.nonEmpty(); stats = stats.tail) { 1297 JCTree stat = stats.head; 1298 if (stat.hasTag(VARDEF)) 1299 switchScope.enter(((JCVariableDecl) stat).sym); 1300 } 1301 } 1302 // where 1303 /** Return the selected enumeration constant symbol, or null. */ 1304 private Symbol enumConstant(JCTree tree, Type enumType) { 1305 if (!tree.hasTag(IDENT)) { 1306 log.error(tree.pos(), "enum.label.must.be.unqualified.enum"); 1307 return syms.errSymbol; 1308 } 1309 JCIdent ident = (JCIdent)tree; 1310 Name name = ident.name; 1311 for (Scope.Entry e = enumType.tsym.members().lookup(name); 1312 e.scope != null; e = e.next()) { 1313 if (e.sym.kind == VAR) { 1314 Symbol s = ident.sym = e.sym; 1315 ((VarSymbol)s).getConstValue(); // ensure initializer is evaluated 1316 ident.type = s.type; 1317 return ((s.flags_field & Flags.ENUM) == 0) 1318 ? null : s; 1319 } 1320 } 1321 return null; 1322 } 1323 1324 public void visitSynchronized(JCSynchronized tree) { 1325 chk.checkRefType(tree.pos(), attribExpr(tree.lock, env)); 1326 attribStat(tree.body, env); 1327 result = null; 1328 } 1329 1330 public void visitTry(JCTry tree) { 1331 // Create a new local environment with a local 1332 Env<AttrContext> localEnv = env.dup(tree, env.info.dup(env.info.scope.dup())); 1333 try { 1334 boolean isTryWithResource = tree.resources.nonEmpty(); 1335 // Create a nested environment for attributing the try block if needed 1336 Env<AttrContext> tryEnv = isTryWithResource ? 1337 env.dup(tree, localEnv.info.dup(localEnv.info.scope.dup())) : 1338 localEnv; 1339 try { 1340 // Attribute resource declarations 1341 for (JCTree resource : tree.resources) { 1342 CheckContext twrContext = new Check.NestedCheckContext(resultInfo.checkContext) { 1343 @Override 1344 public void report(DiagnosticPosition pos, JCDiagnostic details) { 1345 chk.basicHandler.report(pos, diags.fragment("try.not.applicable.to.type", details)); 1346 } 1347 }; 1348 ResultInfo twrResult = new ResultInfo(VAL, syms.autoCloseableType, twrContext); 1349 if (resource.hasTag(VARDEF)) { 1350 attribStat(resource, tryEnv); 1351 twrResult.check(resource, resource.type); 1352 1353 //check that resource type cannot throw InterruptedException 1354 checkAutoCloseable(resource.pos(), localEnv, resource.type); 1355 1356 VarSymbol var = ((JCVariableDecl) resource).sym; 1357 var.setData(ElementKind.RESOURCE_VARIABLE); 1358 } else { 1359 attribTree(resource, tryEnv, twrResult); 1360 } 1361 } 1362 // Attribute body 1363 attribStat(tree.body, tryEnv); 1364 } finally { 1365 if (isTryWithResource) 1366 tryEnv.info.scope.leave(); 1367 } 1368 1369 // Attribute catch clauses 1370 for (List<JCCatch> l = tree.catchers; l.nonEmpty(); l = l.tail) { 1371 JCCatch c = l.head; 1372 Env<AttrContext> catchEnv = 1373 localEnv.dup(c, localEnv.info.dup(localEnv.info.scope.dup())); 1374 try { 1375 Type ctype = attribStat(c.param, catchEnv); 1376 if (TreeInfo.isMultiCatch(c)) { 1377 //multi-catch parameter is implicitly marked as final 1378 c.param.sym.flags_field |= FINAL | UNION; 1379 } 1380 if (c.param.sym.kind == Kinds.VAR) { 1381 c.param.sym.setData(ElementKind.EXCEPTION_PARAMETER); 1382 } 1383 chk.checkType(c.param.vartype.pos(), 1384 chk.checkClassType(c.param.vartype.pos(), ctype), 1385 syms.throwableType); 1386 attribStat(c.body, catchEnv); 1387 } finally { 1388 catchEnv.info.scope.leave(); 1389 } 1390 } 1391 1392 // Attribute finalizer 1393 if (tree.finalizer != null) attribStat(tree.finalizer, localEnv); 1394 result = null; 1395 } 1396 finally { 1397 localEnv.info.scope.leave(); 1398 } 1399 } 1400 1401 void checkAutoCloseable(DiagnosticPosition pos, Env<AttrContext> env, Type resource) { 1402 if (!resource.isErroneous() && 1403 types.asSuper(resource, syms.autoCloseableType.tsym) != null && 1404 !types.isSameType(resource, syms.autoCloseableType)) { // Don't emit warning for AutoCloseable itself 1405 Symbol close = syms.noSymbol; 1406 Log.DiagnosticHandler discardHandler = new Log.DiscardDiagnosticHandler(log); 1407 try { 1408 close = rs.resolveQualifiedMethod(pos, 1409 env, 1410 resource, 1411 names.close, 1412 List.<Type>nil(), 1413 List.<Type>nil()); 1414 } 1415 finally { 1416 log.popDiagnosticHandler(discardHandler); 1417 } 1418 if (close.kind == MTH && 1419 close.overrides(syms.autoCloseableClose, resource.tsym, types, true) && 1420 chk.isHandled(syms.interruptedExceptionType, types.memberType(resource, close).getThrownTypes()) && 1421 env.info.lint.isEnabled(LintCategory.TRY)) { 1422 log.warning(LintCategory.TRY, pos, "try.resource.throws.interrupted.exc", resource); 1423 } 1424 } 1425 } 1426 1427 public void visitConditional(JCConditional tree) { 1428 Type condtype = attribExpr(tree.cond, env, syms.booleanType); 1429 1430 tree.polyKind = (!allowPoly || 1431 pt().hasTag(NONE) && pt() != Type.recoveryType || 1432 isBooleanOrNumeric(env, tree)) ? 1433 PolyKind.STANDALONE : PolyKind.POLY; 1434 1435 if (tree.polyKind == PolyKind.POLY && resultInfo.pt.hasTag(VOID)) { 1436 //cannot get here (i.e. it means we are returning from void method - which is already an error) 1437 resultInfo.checkContext.report(tree, diags.fragment("conditional.target.cant.be.void")); 1438 result = tree.type = types.createErrorType(resultInfo.pt); 1439 return; 1440 } 1441 1442 ResultInfo condInfo = tree.polyKind == PolyKind.STANDALONE ? 1443 unknownExprInfo : 1444 resultInfo.dup(new Check.NestedCheckContext(resultInfo.checkContext) { 1445 //this will use enclosing check context to check compatibility of 1446 //subexpression against target type; if we are in a method check context, 1447 //depending on whether boxing is allowed, we could have incompatibilities 1448 @Override 1449 public void report(DiagnosticPosition pos, JCDiagnostic details) { 1450 enclosingContext.report(pos, diags.fragment("incompatible.type.in.conditional", details)); 1451 } 1452 }); 1453 1454 Type truetype = attribTree(tree.truepart, env, condInfo); 1455 Type falsetype = attribTree(tree.falsepart, env, condInfo); 1456 1457 Type owntype = (tree.polyKind == PolyKind.STANDALONE) ? condType(tree, truetype, falsetype) : pt(); 1458 if (condtype.constValue() != null && 1459 truetype.constValue() != null && 1460 falsetype.constValue() != null && 1461 !owntype.hasTag(NONE)) { 1462 //constant folding 1463 owntype = cfolder.coerce(condtype.isTrue() ? truetype : falsetype, owntype); 1464 } 1465 result = check(tree, owntype, VAL, resultInfo); 1466 } 1467 //where 1468 private boolean isBooleanOrNumeric(Env<AttrContext> env, JCExpression tree) { 1469 switch (tree.getTag()) { 1470 case LITERAL: return ((JCLiteral)tree).typetag.isSubRangeOf(DOUBLE) || 1471 ((JCLiteral)tree).typetag == BOOLEAN || 1472 ((JCLiteral)tree).typetag == BOT; 1473 case LAMBDA: case REFERENCE: return false; 1474 case PARENS: return isBooleanOrNumeric(env, ((JCParens)tree).expr); 1475 case CONDEXPR: 1476 JCConditional condTree = (JCConditional)tree; 1477 return isBooleanOrNumeric(env, condTree.truepart) && 1478 isBooleanOrNumeric(env, condTree.falsepart); 1479 case APPLY: 1480 JCMethodInvocation speculativeMethodTree = 1481 (JCMethodInvocation)deferredAttr.attribSpeculative(tree, env, unknownExprInfo); 1482 Type owntype = TreeInfo.symbol(speculativeMethodTree.meth).type.getReturnType(); 1483 return types.unboxedTypeOrType(owntype).isPrimitive(); 1484 case NEWCLASS: 1485 JCExpression className = 1486 removeClassParams.translate(((JCNewClass)tree).clazz); 1487 JCExpression speculativeNewClassTree = 1488 (JCExpression)deferredAttr.attribSpeculative(className, env, unknownTypeInfo); 1489 return types.unboxedTypeOrType(speculativeNewClassTree.type).isPrimitive(); 1490 default: 1491 Type speculativeType = deferredAttr.attribSpeculative(tree, env, unknownExprInfo).type; 1492 speculativeType = types.unboxedTypeOrType(speculativeType); 1493 return speculativeType.isPrimitive(); 1494 } 1495 } 1496 //where 1497 TreeTranslator removeClassParams = new TreeTranslator() { 1498 @Override 1499 public void visitTypeApply(JCTypeApply tree) { 1500 result = translate(tree.clazz); 1501 } 1502 }; 1503 1504 /** Compute the type of a conditional expression, after 1505 * checking that it exists. See JLS 15.25. Does not take into 1506 * account the special case where condition and both arms 1507 * are constants. 1508 * 1509 * @param pos The source position to be used for error 1510 * diagnostics. 1511 * @param thentype The type of the expression's then-part. 1512 * @param elsetype The type of the expression's else-part. 1513 */ 1514 private Type condType(DiagnosticPosition pos, 1515 Type thentype, Type elsetype) { 1516 // If same type, that is the result 1517 if (types.isSameType(thentype, elsetype)) 1518 return thentype.baseType(); 1519 1520 Type thenUnboxed = (!allowBoxing || thentype.isPrimitive()) 1521 ? thentype : types.unboxedType(thentype); 1522 Type elseUnboxed = (!allowBoxing || elsetype.isPrimitive()) 1523 ? elsetype : types.unboxedType(elsetype); 1524 1525 // Otherwise, if both arms can be converted to a numeric 1526 // type, return the least numeric type that fits both arms 1527 // (i.e. return larger of the two, or return int if one 1528 // arm is short, the other is char). 1529 if (thenUnboxed.isPrimitive() && elseUnboxed.isPrimitive()) { 1530 // If one arm has an integer subrange type (i.e., byte, 1531 // short, or char), and the other is an integer constant 1532 // that fits into the subrange, return the subrange type. 1533 if (thenUnboxed.getTag().isStrictSubRangeOf(INT) && elseUnboxed.hasTag(INT) && 1534 types.isAssignable(elseUnboxed, thenUnboxed)) 1535 return thenUnboxed.baseType(); 1536 if (elseUnboxed.getTag().isStrictSubRangeOf(INT) && thenUnboxed.hasTag(INT) && 1537 types.isAssignable(thenUnboxed, elseUnboxed)) 1538 return elseUnboxed.baseType(); 1539 1540 for (TypeTag tag : TypeTag.values()) { 1541 if (tag.ordinal() >= TypeTag.getTypeTagCount()) break; 1542 Type candidate = syms.typeOfTag[tag.ordinal()]; 1543 if (candidate != null && 1544 candidate.isPrimitive() && 1545 types.isSubtype(thenUnboxed, candidate) && 1546 types.isSubtype(elseUnboxed, candidate)) 1547 return candidate; 1548 } 1549 } 1550 1551 // Those were all the cases that could result in a primitive 1552 if (allowBoxing) { 1553 if (thentype.isPrimitive()) 1554 thentype = types.boxedClass(thentype).type; 1555 if (elsetype.isPrimitive()) 1556 elsetype = types.boxedClass(elsetype).type; 1557 } 1558 1559 if (types.isSubtype(thentype, elsetype)) 1560 return elsetype.baseType(); 1561 if (types.isSubtype(elsetype, thentype)) 1562 return thentype.baseType(); 1563 1564 if (!allowBoxing || thentype.hasTag(VOID) || elsetype.hasTag(VOID)) { 1565 log.error(pos, "neither.conditional.subtype", 1566 thentype, elsetype); 1567 return thentype.baseType(); 1568 } 1569 1570 // both are known to be reference types. The result is 1571 // lub(thentype,elsetype). This cannot fail, as it will 1572 // always be possible to infer "Object" if nothing better. 1573 return types.lub(thentype.baseType(), elsetype.baseType()); 1574 } 1575 1576 public void visitIf(JCIf tree) { 1577 attribExpr(tree.cond, env, syms.booleanType); 1578 attribStat(tree.thenpart, env); 1579 if (tree.elsepart != null) 1580 attribStat(tree.elsepart, env); 1581 chk.checkEmptyIf(tree); 1582 result = null; 1583 } 1584 1585 public void visitExec(JCExpressionStatement tree) { 1586 //a fresh environment is required for 292 inference to work properly --- 1587 //see Infer.instantiatePolymorphicSignatureInstance() 1588 Env<AttrContext> localEnv = env.dup(tree); 1589 attribExpr(tree.expr, localEnv); 1590 result = null; 1591 } 1592 1593 public void visitBreak(JCBreak tree) { 1594 tree.target = findJumpTarget(tree.pos(), tree.getTag(), tree.label, env); 1595 result = null; 1596 } 1597 1598 public void visitContinue(JCContinue tree) { 1599 tree.target = findJumpTarget(tree.pos(), tree.getTag(), tree.label, env); 1600 result = null; 1601 } 1602 //where 1603 /** Return the target of a break or continue statement, if it exists, 1604 * report an error if not. 1605 * Note: The target of a labelled break or continue is the 1606 * (non-labelled) statement tree referred to by the label, 1607 * not the tree representing the labelled statement itself. 1608 * 1609 * @param pos The position to be used for error diagnostics 1610 * @param tag The tag of the jump statement. This is either 1611 * Tree.BREAK or Tree.CONTINUE. 1612 * @param label The label of the jump statement, or null if no 1613 * label is given. 1614 * @param env The environment current at the jump statement. 1615 */ 1616 private JCTree findJumpTarget(DiagnosticPosition pos, 1617 JCTree.Tag tag, 1618 Name label, 1619 Env<AttrContext> env) { 1620 // Search environments outwards from the point of jump. 1621 Env<AttrContext> env1 = env; 1622 LOOP: 1623 while (env1 != null) { 1624 switch (env1.tree.getTag()) { 1625 case LABELLED: 1626 JCLabeledStatement labelled = (JCLabeledStatement)env1.tree; 1627 if (label == labelled.label) { 1628 // If jump is a continue, check that target is a loop. 1629 if (tag == CONTINUE) { 1630 if (!labelled.body.hasTag(DOLOOP) && 1631 !labelled.body.hasTag(WHILELOOP) && 1632 !labelled.body.hasTag(FORLOOP) && 1633 !labelled.body.hasTag(FOREACHLOOP)) 1634 log.error(pos, "not.loop.label", label); 1635 // Found labelled statement target, now go inwards 1636 // to next non-labelled tree. 1637 return TreeInfo.referencedStatement(labelled); 1638 } else { 1639 return labelled; 1640 } 1641 } 1642 break; 1643 case DOLOOP: 1644 case WHILELOOP: 1645 case FORLOOP: 1646 case FOREACHLOOP: 1647 if (label == null) return env1.tree; 1648 break; 1649 case SWITCH: 1650 if (label == null && tag == BREAK) return env1.tree; 1651 break; 1652 case LAMBDA: 1653 case METHODDEF: 1654 case CLASSDEF: 1655 break LOOP; 1656 default: 1657 } 1658 env1 = env1.next; 1659 } 1660 if (label != null) 1661 log.error(pos, "undef.label", label); 1662 else if (tag == CONTINUE) 1663 log.error(pos, "cont.outside.loop"); 1664 else 1665 log.error(pos, "break.outside.switch.loop"); 1666 return null; 1667 } 1668 1669 public void visitReturn(JCReturn tree) { 1670 // Check that there is an enclosing method which is 1671 // nested within than the enclosing class. 1672 if (env.info.returnResult == null) { 1673 log.error(tree.pos(), "ret.outside.meth"); 1674 } else { 1675 // Attribute return expression, if it exists, and check that 1676 // it conforms to result type of enclosing method. 1677 if (tree.expr != null) { 1678 if (env.info.returnResult.pt.hasTag(VOID)) { 1679 env.info.returnResult.checkContext.report(tree.expr.pos(), 1680 diags.fragment("unexpected.ret.val")); 1681 } 1682 attribTree(tree.expr, env, env.info.returnResult); 1683 } else if (!env.info.returnResult.pt.hasTag(VOID)) { 1684 env.info.returnResult.checkContext.report(tree.pos(), 1685 diags.fragment("missing.ret.val")); 1686 } 1687 } 1688 result = null; 1689 } 1690 1691 public void visitThrow(JCThrow tree) { 1692 Type owntype = attribExpr(tree.expr, env, allowPoly ? Type.noType : syms.throwableType); 1693 if (allowPoly) { 1694 chk.checkType(tree, owntype, syms.throwableType); 1695 } 1696 result = null; 1697 } 1698 1699 public void visitAssert(JCAssert tree) { 1700 attribExpr(tree.cond, env, syms.booleanType); 1701 if (tree.detail != null) { 1702 chk.checkNonVoid(tree.detail.pos(), attribExpr(tree.detail, env)); 1703 } 1704 result = null; 1705 } 1706 1707 /** Visitor method for method invocations. 1708 * NOTE: The method part of an application will have in its type field 1709 * the return type of the method, not the method's type itself! 1710 */ 1711 public void visitApply(JCMethodInvocation tree) { 1712 // The local environment of a method application is 1713 // a new environment nested in the current one. 1714 Env<AttrContext> localEnv = env.dup(tree, env.info.dup()); 1715 1716 // The types of the actual method arguments. 1717 List<Type> argtypes; 1718 1719 // The types of the actual method type arguments. 1720 List<Type> typeargtypes = null; 1721 1722 Name methName = TreeInfo.name(tree.meth); 1723 1724 boolean isConstructorCall = 1725 methName == names._this || methName == names._super; 1726 1727 if (isConstructorCall) { 1728 // We are seeing a ...this(...) or ...super(...) call. 1729 // Check that this is the first statement in a constructor. 1730 if (checkFirstConstructorStat(tree, env)) { 1731 1732 // Record the fact 1733 // that this is a constructor call (using isSelfCall). 1734 localEnv.info.isSelfCall = true; 1735 1736 // Attribute arguments, yielding list of argument types. 1737 argtypes = attribArgs(tree.args, localEnv); 1738 typeargtypes = attribTypes(tree.typeargs, localEnv); 1739 1740 // Variable `site' points to the class in which the called 1741 // constructor is defined. 1742 Type site = env.enclClass.sym.type; 1743 if (methName == names._super) { 1744 if (site == syms.objectType) { 1745 log.error(tree.meth.pos(), "no.superclass", site); 1746 site = types.createErrorType(syms.objectType); 1747 } else { 1748 site = types.supertype(site); 1749 } 1750 } 1751 1752 if (site.hasTag(CLASS)) { 1753 Type encl = site.getEnclosingType(); 1754 while (encl != null && encl.hasTag(TYPEVAR)) 1755 encl = encl.getUpperBound(); 1756 if (encl.hasTag(CLASS)) { 1757 // we are calling a nested class 1758 1759 if (tree.meth.hasTag(SELECT)) { 1760 JCTree qualifier = ((JCFieldAccess) tree.meth).selected; 1761 1762 // We are seeing a prefixed call, of the form 1763 // <expr>.super(...). 1764 // Check that the prefix expression conforms 1765 // to the outer instance type of the class. 1766 chk.checkRefType(qualifier.pos(), 1767 attribExpr(qualifier, localEnv, 1768 encl)); 1769 } else if (methName == names._super) { 1770 // qualifier omitted; check for existence 1771 // of an appropriate implicit qualifier. 1772 rs.resolveImplicitThis(tree.meth.pos(), 1773 localEnv, site, true); 1774 } 1775 } else if (tree.meth.hasTag(SELECT)) { 1776 log.error(tree.meth.pos(), "illegal.qual.not.icls", 1777 site.tsym); 1778 } 1779 1780 // if we're calling a java.lang.Enum constructor, 1781 // prefix the implicit String and int parameters 1782 if (site.tsym == syms.enumSym && allowEnums) 1783 argtypes = argtypes.prepend(syms.intType).prepend(syms.stringType); 1784 1785 // Resolve the called constructor under the assumption 1786 // that we are referring to a superclass instance of the 1787 // current instance (JLS ???). 1788 boolean selectSuperPrev = localEnv.info.selectSuper; 1789 localEnv.info.selectSuper = true; 1790 localEnv.info.pendingResolutionPhase = null; 1791 Symbol sym = rs.resolveConstructor( 1792 tree.meth.pos(), localEnv, site, argtypes, typeargtypes); 1793 localEnv.info.selectSuper = selectSuperPrev; 1794 1795 // Set method symbol to resolved constructor... 1796 TreeInfo.setSymbol(tree.meth, sym); 1797 1798 // ...and check that it is legal in the current context. 1799 // (this will also set the tree's type) 1800 Type mpt = newMethodTemplate(resultInfo.pt, argtypes, typeargtypes); 1801 checkId(tree.meth, site, sym, localEnv, new ResultInfo(MTH, mpt)); 1802 } 1803 // Otherwise, `site' is an error type and we do nothing 1804 } 1805 result = tree.type = syms.voidType; 1806 } else { 1807 // Otherwise, we are seeing a regular method call. 1808 // Attribute the arguments, yielding list of argument types, ... 1809 argtypes = attribArgs(tree.args, localEnv); 1810 typeargtypes = attribAnyTypes(tree.typeargs, localEnv); 1811 1812 // ... and attribute the method using as a prototype a methodtype 1813 // whose formal argument types is exactly the list of actual 1814 // arguments (this will also set the method symbol). 1815 Type mpt = newMethodTemplate(resultInfo.pt, argtypes, typeargtypes); 1816 localEnv.info.pendingResolutionPhase = null; 1817 Type mtype = attribTree(tree.meth, localEnv, new ResultInfo(VAL, mpt, resultInfo.checkContext)); 1818 1819 // Compute the result type. 1820 Type restype = mtype.getReturnType(); 1821 if (restype.hasTag(WILDCARD)) 1822 throw new AssertionError(mtype); 1823 1824 Type qualifier = (tree.meth.hasTag(SELECT)) 1825 ? ((JCFieldAccess) tree.meth).selected.type 1826 : env.enclClass.sym.type; 1827 restype = adjustMethodReturnType(qualifier, methName, argtypes, restype); 1828 1829 chk.checkRefTypes(tree.typeargs, typeargtypes); 1830 1831 // Check that value of resulting type is admissible in the 1832 // current context. Also, capture the return type 1833 result = check(tree, capture(restype), VAL, resultInfo); 1834 1835 if (localEnv.info.lastResolveVarargs()) 1836 Assert.check(result.isErroneous() || tree.varargsElement != null); 1837 } 1838 chk.validate(tree.typeargs, localEnv); 1839 } 1840 //where 1841 Type adjustMethodReturnType(Type qualifierType, Name methodName, List<Type> argtypes, Type restype) { 1842 if (allowCovariantReturns && 1843 methodName == names.clone && 1844 types.isArray(qualifierType)) { 1845 // as a special case, array.clone() has a result that is 1846 // the same as static type of the array being cloned 1847 return qualifierType; 1848 } else if (allowGenerics && 1849 methodName == names.getClass && 1850 argtypes.isEmpty()) { 1851 // as a special case, x.getClass() has type Class<? extends |X|> 1852 return new ClassType(restype.getEnclosingType(), 1853 List.<Type>of(new WildcardType(types.erasure(qualifierType), 1854 BoundKind.EXTENDS, 1855 syms.boundClass)), 1856 restype.tsym); 1857 } else { 1858 return restype; 1859 } 1860 } 1861 1862 /** Check that given application node appears as first statement 1863 * in a constructor call. 1864 * @param tree The application node 1865 * @param env The environment current at the application. 1866 */ 1867 boolean checkFirstConstructorStat(JCMethodInvocation tree, Env<AttrContext> env) { 1868 JCMethodDecl enclMethod = env.enclMethod; 1869 if (enclMethod != null && enclMethod.name == names.init) { 1870 JCBlock body = enclMethod.body; 1871 if (body.stats.head.hasTag(EXEC) && 1872 ((JCExpressionStatement) body.stats.head).expr == tree) 1873 return true; 1874 } 1875 log.error(tree.pos(),"call.must.be.first.stmt.in.ctor", 1876 TreeInfo.name(tree.meth)); 1877 return false; 1878 } 1879 1880 /** Obtain a method type with given argument types. 1881 */ 1882 Type newMethodTemplate(Type restype, List<Type> argtypes, List<Type> typeargtypes) { 1883 MethodType mt = new MethodType(argtypes, restype, List.<Type>nil(), syms.methodClass); 1884 return (typeargtypes == null) ? mt : (Type)new ForAll(typeargtypes, mt); 1885 } 1886 1887 public void visitNewClass(final JCNewClass tree) { 1888 Type owntype = types.createErrorType(tree.type); 1889 1890 // The local environment of a class creation is 1891 // a new environment nested in the current one. 1892 Env<AttrContext> localEnv = env.dup(tree, env.info.dup()); 1893 1894 // The anonymous inner class definition of the new expression, 1895 // if one is defined by it. 1896 JCClassDecl cdef = tree.def; 1897 1898 // If enclosing class is given, attribute it, and 1899 // complete class name to be fully qualified 1900 JCExpression clazz = tree.clazz; // Class field following new 1901 JCExpression clazzid; // Identifier in class field 1902 JCAnnotatedType annoclazzid; // Annotated type enclosing clazzid 1903 annoclazzid = null; 1904 1905 if (clazz.hasTag(TYPEAPPLY)) { 1906 clazzid = ((JCTypeApply) clazz).clazz; 1907 if (clazzid.hasTag(ANNOTATED_TYPE)) { 1908 annoclazzid = (JCAnnotatedType) clazzid; 1909 clazzid = annoclazzid.underlyingType; 1910 } 1911 } else { 1912 if (clazz.hasTag(ANNOTATED_TYPE)) { 1913 annoclazzid = (JCAnnotatedType) clazz; 1914 clazzid = annoclazzid.underlyingType; 1915 } else { 1916 clazzid = clazz; 1917 } 1918 } 1919 1920 JCExpression clazzid1 = clazzid; // The same in fully qualified form 1921 1922 if (tree.encl != null) { 1923 // We are seeing a qualified new, of the form 1924 // <expr>.new C <...> (...) ... 1925 // In this case, we let clazz stand for the name of the 1926 // allocated class C prefixed with the type of the qualifier 1927 // expression, so that we can 1928 // resolve it with standard techniques later. I.e., if 1929 // <expr> has type T, then <expr>.new C <...> (...) 1930 // yields a clazz T.C. 1931 Type encltype = chk.checkRefType(tree.encl.pos(), 1932 attribExpr(tree.encl, env)); 1933 // TODO 308: in <expr>.new C, do we also want to add the type annotations 1934 // from expr to the combined type, or not? Yes, do this. 1935 clazzid1 = make.at(clazz.pos).Select(make.Type(encltype), 1936 ((JCIdent) clazzid).name); 1937 1938 if (clazz.hasTag(ANNOTATED_TYPE)) { 1939 JCAnnotatedType annoType = (JCAnnotatedType) clazz; 1940 List<JCAnnotation> annos = annoType.annotations; 1941 1942 if (annoType.underlyingType.hasTag(TYPEAPPLY)) { 1943 clazzid1 = make.at(tree.pos). 1944 TypeApply(clazzid1, 1945 ((JCTypeApply) clazz).arguments); 1946 } 1947 1948 clazzid1 = make.at(tree.pos). 1949 AnnotatedType(annos, clazzid1); 1950 } else if (clazz.hasTag(TYPEAPPLY)) { 1951 clazzid1 = make.at(tree.pos). 1952 TypeApply(clazzid1, 1953 ((JCTypeApply) clazz).arguments); 1954 } 1955 1956 clazz = clazzid1; 1957 } 1958 1959 // Attribute clazz expression and store 1960 // symbol + type back into the attributed tree. 1961 Type clazztype = TreeInfo.isEnumInit(env.tree) ? 1962 attribIdentAsEnumType(env, (JCIdent)clazz) : 1963 attribType(clazz, env); 1964 1965 clazztype = chk.checkDiamond(tree, clazztype); 1966 chk.validate(clazz, localEnv); 1967 if (tree.encl != null) { 1968 // We have to work in this case to store 1969 // symbol + type back into the attributed tree. 1970 tree.clazz.type = clazztype; 1971 TreeInfo.setSymbol(clazzid, TreeInfo.symbol(clazzid1)); 1972 clazzid.type = ((JCIdent) clazzid).sym.type; 1973 if (annoclazzid != null) { 1974 annoclazzid.type = clazzid.type; 1975 } 1976 if (!clazztype.isErroneous()) { 1977 if (cdef != null && clazztype.tsym.isInterface()) { 1978 log.error(tree.encl.pos(), "anon.class.impl.intf.no.qual.for.new"); 1979 } else if (clazztype.tsym.isStatic()) { 1980 log.error(tree.encl.pos(), "qualified.new.of.static.class", clazztype.tsym); 1981 } 1982 } 1983 } else if (!clazztype.tsym.isInterface() && 1984 clazztype.getEnclosingType().hasTag(CLASS)) { 1985 // Check for the existence of an apropos outer instance 1986 rs.resolveImplicitThis(tree.pos(), env, clazztype); 1987 } 1988 1989 // Attribute constructor arguments. 1990 List<Type> argtypes = attribArgs(tree.args, localEnv); 1991 List<Type> typeargtypes = attribTypes(tree.typeargs, localEnv); 1992 1993 // If we have made no mistakes in the class type... 1994 if (clazztype.hasTag(CLASS)) { 1995 // Enums may not be instantiated except implicitly 1996 if (allowEnums && 1997 (clazztype.tsym.flags_field&Flags.ENUM) != 0 && 1998 (!env.tree.hasTag(VARDEF) || 1999 (((JCVariableDecl) env.tree).mods.flags&Flags.ENUM) == 0 || 2000 ((JCVariableDecl) env.tree).init != tree)) 2001 log.error(tree.pos(), "enum.cant.be.instantiated"); 2002 // Check that class is not abstract 2003 if (cdef == null && 2004 (clazztype.tsym.flags() & (ABSTRACT | INTERFACE)) != 0) { 2005 log.error(tree.pos(), "abstract.cant.be.instantiated", 2006 clazztype.tsym); 2007 } else if (cdef != null && clazztype.tsym.isInterface()) { 2008 // Check that no constructor arguments are given to 2009 // anonymous classes implementing an interface 2010 if (!argtypes.isEmpty()) 2011 log.error(tree.args.head.pos(), "anon.class.impl.intf.no.args"); 2012 2013 if (!typeargtypes.isEmpty()) 2014 log.error(tree.typeargs.head.pos(), "anon.class.impl.intf.no.typeargs"); 2015 2016 // Error recovery: pretend no arguments were supplied. 2017 argtypes = List.nil(); 2018 typeargtypes = List.nil(); 2019 } else if (TreeInfo.isDiamond(tree)) { 2020 ClassType site = new ClassType(clazztype.getEnclosingType(), 2021 clazztype.tsym.type.getTypeArguments(), 2022 clazztype.tsym); 2023 2024 Env<AttrContext> diamondEnv = localEnv.dup(tree); 2025 diamondEnv.info.selectSuper = cdef != null; 2026 diamondEnv.info.pendingResolutionPhase = null; 2027 2028 //if the type of the instance creation expression is a class type 2029 //apply method resolution inference (JLS 15.12.2.7). The return type 2030 //of the resolved constructor will be a partially instantiated type 2031 Symbol constructor = rs.resolveDiamond(tree.pos(), 2032 diamondEnv, 2033 site, 2034 argtypes, 2035 typeargtypes); 2036 tree.constructor = constructor.baseSymbol(); 2037 2038 final TypeSymbol csym = clazztype.tsym; 2039 ResultInfo diamondResult = new ResultInfo(MTH, newMethodTemplate(resultInfo.pt, argtypes, typeargtypes), new Check.NestedCheckContext(resultInfo.checkContext) { 2040 @Override 2041 public void report(DiagnosticPosition _unused, JCDiagnostic details) { 2042 enclosingContext.report(tree.clazz, 2043 diags.fragment("cant.apply.diamond.1", diags.fragment("diamond", csym), details)); 2044 } 2045 }); 2046 Type constructorType = tree.constructorType = types.createErrorType(clazztype); 2047 constructorType = checkId(tree, site, 2048 constructor, 2049 diamondEnv, 2050 diamondResult); 2051 2052 tree.clazz.type = types.createErrorType(clazztype); 2053 if (!constructorType.isErroneous()) { 2054 tree.clazz.type = clazztype = constructorType.getReturnType(); 2055 tree.constructorType = types.createMethodTypeWithReturn(constructorType, syms.voidType); 2056 } 2057 clazztype = chk.checkClassType(tree.clazz, tree.clazz.type, true); 2058 } 2059 2060 // Resolve the called constructor under the assumption 2061 // that we are referring to a superclass instance of the 2062 // current instance (JLS ???). 2063 else { 2064 //the following code alters some of the fields in the current 2065 //AttrContext - hence, the current context must be dup'ed in 2066 //order to avoid downstream failures 2067 Env<AttrContext> rsEnv = localEnv.dup(tree); 2068 rsEnv.info.selectSuper = cdef != null; 2069 rsEnv.info.pendingResolutionPhase = null; 2070 tree.constructor = rs.resolveConstructor( 2071 tree.pos(), rsEnv, clazztype, argtypes, typeargtypes); 2072 if (cdef == null) { //do not check twice! 2073 tree.constructorType = checkId(tree, 2074 clazztype, 2075 tree.constructor, 2076 rsEnv, 2077 new ResultInfo(MTH, newMethodTemplate(syms.voidType, argtypes, typeargtypes))); 2078 if (rsEnv.info.lastResolveVarargs()) 2079 Assert.check(tree.constructorType.isErroneous() || tree.varargsElement != null); 2080 } 2081 findDiamondIfNeeded(localEnv, tree, clazztype); 2082 } 2083 2084 if (cdef != null) { 2085 // We are seeing an anonymous class instance creation. 2086 // In this case, the class instance creation 2087 // expression 2088 // 2089 // E.new <typeargs1>C<typargs2>(args) { ... } 2090 // 2091 // is represented internally as 2092 // 2093 // E . new <typeargs1>C<typargs2>(args) ( class <empty-name> { ... } ) . 2094 // 2095 // This expression is then *transformed* as follows: 2096 // 2097 // (1) add a STATIC flag to the class definition 2098 // if the current environment is static 2099 // (2) add an extends or implements clause 2100 // (3) add a constructor. 2101 // 2102 // For instance, if C is a class, and ET is the type of E, 2103 // the expression 2104 // 2105 // E.new <typeargs1>C<typargs2>(args) { ... } 2106 // 2107 // is translated to (where X is a fresh name and typarams is the 2108 // parameter list of the super constructor): 2109 // 2110 // new <typeargs1>X(<*nullchk*>E, args) where 2111 // X extends C<typargs2> { 2112 // <typarams> X(ET e, args) { 2113 // e.<typeargs1>super(args) 2114 // } 2115 // ... 2116 // } 2117 if (Resolve.isStatic(env)) cdef.mods.flags |= STATIC; 2118 2119 if (clazztype.tsym.isInterface()) { 2120 cdef.implementing = List.of(clazz); 2121 } else { 2122 cdef.extending = clazz; 2123 } 2124 2125 attribStat(cdef, localEnv); 2126 2127 checkLambdaCandidate(tree, cdef.sym, clazztype); 2128 2129 // If an outer instance is given, 2130 // prefix it to the constructor arguments 2131 // and delete it from the new expression 2132 if (tree.encl != null && !clazztype.tsym.isInterface()) { 2133 tree.args = tree.args.prepend(makeNullCheck(tree.encl)); 2134 argtypes = argtypes.prepend(tree.encl.type); 2135 tree.encl = null; 2136 } 2137 2138 // Reassign clazztype and recompute constructor. 2139 clazztype = cdef.sym.type; 2140 Symbol sym = tree.constructor = rs.resolveConstructor( 2141 tree.pos(), localEnv, clazztype, argtypes, typeargtypes); 2142 Assert.check(sym.kind < AMBIGUOUS); 2143 tree.constructor = sym; 2144 tree.constructorType = checkId(tree, 2145 clazztype, 2146 tree.constructor, 2147 localEnv, 2148 new ResultInfo(VAL, newMethodTemplate(syms.voidType, argtypes, typeargtypes))); 2149 } else { 2150 if (tree.clazz.hasTag(ANNOTATED_TYPE)) { 2151 checkForDeclarationAnnotations(((JCAnnotatedType) tree.clazz).annotations, 2152 tree.clazz.type.tsym); 2153 } 2154 } 2155 2156 if (tree.constructor != null && tree.constructor.kind == MTH) 2157 owntype = clazztype; 2158 } 2159 result = check(tree, owntype, VAL, resultInfo); 2160 chk.validate(tree.typeargs, localEnv); 2161 } 2162 //where 2163 void findDiamondIfNeeded(Env<AttrContext> env, JCNewClass tree, Type clazztype) { 2164 if (tree.def == null && 2165 !clazztype.isErroneous() && 2166 clazztype.getTypeArguments().nonEmpty() && 2167 findDiamonds) { 2168 JCTypeApply ta = (JCTypeApply)tree.clazz; 2169 List<JCExpression> prevTypeargs = ta.arguments; 2170 try { 2171 //create a 'fake' diamond AST node by removing type-argument trees 2172 ta.arguments = List.nil(); 2173 ResultInfo findDiamondResult = new ResultInfo(VAL, 2174 resultInfo.checkContext.inferenceContext().free(resultInfo.pt) ? Type.noType : pt()); 2175 Type inferred = deferredAttr.attribSpeculative(tree, env, findDiamondResult).type; 2176 Type polyPt = allowPoly ? 2177 syms.objectType : 2178 clazztype; 2179 if (!inferred.isErroneous() && 2180 types.isAssignable(inferred, pt().hasTag(NONE) ? polyPt : pt(), types.noWarnings)) { 2181 String key = types.isSameType(clazztype, inferred) ? 2182 "diamond.redundant.args" : 2183 "diamond.redundant.args.1"; 2184 log.warning(tree.clazz.pos(), key, clazztype, inferred); 2185 } 2186 } finally { 2187 ta.arguments = prevTypeargs; 2188 } 2189 } 2190 } 2191 2192 private void checkLambdaCandidate(JCNewClass tree, ClassSymbol csym, Type clazztype) { 2193 if (allowLambda && 2194 identifyLambdaCandidate && 2195 clazztype.hasTag(CLASS) && 2196 !pt().hasTag(NONE) && 2197 types.isFunctionalInterface(clazztype.tsym)) { 2198 Symbol descriptor = types.findDescriptorSymbol(clazztype.tsym); 2199 int count = 0; 2200 boolean found = false; 2201 for (Symbol sym : csym.members().getElements()) { 2202 if ((sym.flags() & SYNTHETIC) != 0 || 2203 sym.isConstructor()) continue; 2204 count++; 2205 if (sym.kind != MTH || 2206 !sym.name.equals(descriptor.name)) continue; 2207 Type mtype = types.memberType(clazztype, sym); 2208 if (types.overrideEquivalent(mtype, types.memberType(clazztype, descriptor))) { 2209 found = true; 2210 } 2211 } 2212 if (found && count == 1) { 2213 log.note(tree.def, "potential.lambda.found"); 2214 } 2215 } 2216 } 2217 2218 private void checkForDeclarationAnnotations(List<? extends JCAnnotation> annotations, 2219 Symbol sym) { 2220 // Ensure that no declaration annotations are present. 2221 // Note that a tree type might be an AnnotatedType with 2222 // empty annotations, if only declaration annotations were given. 2223 // This method will raise an error for such a type. 2224 for (JCAnnotation ai : annotations) { 2225 if (TypeAnnotations.annotationType(syms, names, ai.attribute, sym) == TypeAnnotations.AnnotationType.DECLARATION) { 2226 log.error(ai.pos(), "annotation.type.not.applicable"); 2227 } 2228 } 2229 } 2230 2231 2232 /** Make an attributed null check tree. 2233 */ 2234 public JCExpression makeNullCheck(JCExpression arg) { 2235 // optimization: X.this is never null; skip null check 2236 Name name = TreeInfo.name(arg); 2237 if (name == names._this || name == names._super) return arg; 2238 2239 JCTree.Tag optag = NULLCHK; 2240 JCUnary tree = make.at(arg.pos).Unary(optag, arg); 2241 tree.operator = syms.nullcheck; 2242 tree.type = arg.type; 2243 return tree; 2244 } 2245 2246 public void visitNewArray(JCNewArray tree) { 2247 Type owntype = types.createErrorType(tree.type); 2248 Env<AttrContext> localEnv = env.dup(tree); 2249 Type elemtype; 2250 if (tree.elemtype != null) { 2251 elemtype = attribType(tree.elemtype, localEnv); 2252 chk.validate(tree.elemtype, localEnv); 2253 owntype = elemtype; 2254 for (List<JCExpression> l = tree.dims; l.nonEmpty(); l = l.tail) { 2255 attribExpr(l.head, localEnv, syms.intType); 2256 owntype = new ArrayType(owntype, syms.arrayClass); 2257 } 2258 if (tree.elemtype.hasTag(ANNOTATED_TYPE)) { 2259 checkForDeclarationAnnotations(((JCAnnotatedType) tree.elemtype).annotations, 2260 tree.elemtype.type.tsym); 2261 } 2262 } else { 2263 // we are seeing an untyped aggregate { ... } 2264 // this is allowed only if the prototype is an array 2265 if (pt().hasTag(ARRAY)) { 2266 elemtype = types.elemtype(pt()); 2267 } else { 2268 if (!pt().hasTag(ERROR)) { 2269 log.error(tree.pos(), "illegal.initializer.for.type", 2270 pt()); 2271 } 2272 elemtype = types.createErrorType(pt()); 2273 } 2274 } 2275 if (tree.elems != null) { 2276 attribExprs(tree.elems, localEnv, elemtype); 2277 owntype = new ArrayType(elemtype, syms.arrayClass); 2278 } 2279 if (!types.isReifiable(elemtype)) 2280 log.error(tree.pos(), "generic.array.creation"); 2281 result = check(tree, owntype, VAL, resultInfo); 2282 } 2283 2284 /* 2285 * A lambda expression can only be attributed when a target-type is available. 2286 * In addition, if the target-type is that of a functional interface whose 2287 * descriptor contains inference variables in argument position the lambda expression 2288 * is 'stuck' (see DeferredAttr). 2289 */ 2290 @Override 2291 public void visitLambda(final JCLambda that) { 2292 if (pt().isErroneous() || (pt().hasTag(NONE) && pt() != Type.recoveryType)) { 2293 if (pt().hasTag(NONE)) { 2294 //lambda only allowed in assignment or method invocation/cast context 2295 log.error(that.pos(), "unexpected.lambda"); 2296 } 2297 result = that.type = types.createErrorType(pt()); 2298 return; 2299 } 2300 //create an environment for attribution of the lambda expression 2301 final Env<AttrContext> localEnv = lambdaEnv(that, env); 2302 boolean needsRecovery = 2303 resultInfo.checkContext.deferredAttrContext().mode == DeferredAttr.AttrMode.CHECK; 2304 try { 2305 Type target = pt(); 2306 List<Type> explicitParamTypes = null; 2307 if (that.paramKind == JCLambda.ParameterKind.EXPLICIT) { 2308 //attribute lambda parameters 2309 attribStats(that.params, localEnv); 2310 explicitParamTypes = TreeInfo.types(that.params); 2311 target = infer.instantiateFunctionalInterface(that, target, explicitParamTypes, resultInfo.checkContext); 2312 } 2313 2314 Type lambdaType; 2315 if (pt() != Type.recoveryType) { 2316 target = targetChecker.visit(target, that); 2317 lambdaType = types.findDescriptorType(target); 2318 chk.checkFunctionalInterface(that, target); 2319 } else { 2320 target = Type.recoveryType; 2321 lambdaType = fallbackDescriptorType(that); 2322 } 2323 2324 setFunctionalInfo(that, pt(), lambdaType, target, resultInfo.checkContext.inferenceContext()); 2325 2326 if (lambdaType.hasTag(FORALL)) { 2327 //lambda expression target desc cannot be a generic method 2328 resultInfo.checkContext.report(that, diags.fragment("invalid.generic.lambda.target", 2329 lambdaType, kindName(target.tsym), target.tsym)); 2330 result = that.type = types.createErrorType(pt()); 2331 return; 2332 } 2333 2334 if (that.paramKind == JCLambda.ParameterKind.IMPLICIT) { 2335 //add param type info in the AST 2336 List<Type> actuals = lambdaType.getParameterTypes(); 2337 List<JCVariableDecl> params = that.params; 2338 2339 boolean arityMismatch = false; 2340 2341 while (params.nonEmpty()) { 2342 if (actuals.isEmpty()) { 2343 //not enough actuals to perform lambda parameter inference 2344 arityMismatch = true; 2345 } 2346 //reset previously set info 2347 Type argType = arityMismatch ? 2348 syms.errType : 2349 actuals.head; 2350 params.head.vartype = make.at(params.head).Type(argType); 2351 params.head.sym = null; 2352 actuals = actuals.isEmpty() ? 2353 actuals : 2354 actuals.tail; 2355 params = params.tail; 2356 } 2357 2358 //attribute lambda parameters 2359 attribStats(that.params, localEnv); 2360 2361 if (arityMismatch) { 2362 resultInfo.checkContext.report(that, diags.fragment("incompatible.arg.types.in.lambda")); 2363 result = that.type = types.createErrorType(target); 2364 return; 2365 } 2366 } 2367 2368 //from this point on, no recovery is needed; if we are in assignment context 2369 //we will be able to attribute the whole lambda body, regardless of errors; 2370 //if we are in a 'check' method context, and the lambda is not compatible 2371 //with the target-type, it will be recovered anyway in Attr.checkId 2372 needsRecovery = false; 2373 2374 FunctionalReturnContext funcContext = that.getBodyKind() == JCLambda.BodyKind.EXPRESSION ? 2375 new ExpressionLambdaReturnContext((JCExpression)that.getBody(), resultInfo.checkContext) : 2376 new FunctionalReturnContext(resultInfo.checkContext); 2377 2378 ResultInfo bodyResultInfo = lambdaType.getReturnType() == Type.recoveryType ? 2379 recoveryInfo : 2380 new ResultInfo(VAL, lambdaType.getReturnType(), funcContext); 2381 localEnv.info.returnResult = bodyResultInfo; 2382 2383 Log.DeferredDiagnosticHandler lambdaDeferredHandler = new Log.DeferredDiagnosticHandler(log); 2384 try { 2385 if (that.getBodyKind() == JCLambda.BodyKind.EXPRESSION) { 2386 attribTree(that.getBody(), localEnv, bodyResultInfo); 2387 } else { 2388 JCBlock body = (JCBlock)that.body; 2389 attribStats(body.stats, localEnv); 2390 } 2391 2392 if (resultInfo.checkContext.deferredAttrContext().mode == AttrMode.SPECULATIVE) { 2393 //check for errors in lambda body 2394 for (JCDiagnostic deferredDiag : lambdaDeferredHandler.getDiagnostics()) { 2395 if (deferredDiag.getKind() == JCDiagnostic.Kind.ERROR) { 2396 resultInfo.checkContext 2397 .report(that, diags.fragment("bad.arg.types.in.lambda", TreeInfo.types(that.params), 2398 deferredDiag)); //hidden diag parameter 2399 //we mark the lambda as erroneous - this is crucial in the recovery step 2400 //as parameter-dependent type error won't be reported in that stage, 2401 //meaning that a lambda will be deemed erroeneous only if there is 2402 //a target-independent error (which will cause method diagnostic 2403 //to be skipped). 2404 result = that.type = types.createErrorType(target); 2405 return; 2406 } 2407 } 2408 } 2409 } finally { 2410 lambdaDeferredHandler.reportDeferredDiagnostics(); 2411 log.popDiagnosticHandler(lambdaDeferredHandler); 2412 } 2413 2414 result = check(that, target, VAL, resultInfo); 2415 2416 boolean isSpeculativeRound = 2417 resultInfo.checkContext.deferredAttrContext().mode == DeferredAttr.AttrMode.SPECULATIVE; 2418 2419 postAttr(that); 2420 flow.analyzeLambda(env, that, make, isSpeculativeRound); 2421 2422 checkLambdaCompatible(that, lambdaType, resultInfo.checkContext, isSpeculativeRound); 2423 2424 if (!isSpeculativeRound) { 2425 checkAccessibleTypes(that, localEnv, resultInfo.checkContext.inferenceContext(), lambdaType, target); 2426 } 2427 result = check(that, target, VAL, resultInfo); 2428 } catch (Types.FunctionDescriptorLookupError ex) { 2429 JCDiagnostic cause = ex.getDiagnostic(); 2430 resultInfo.checkContext.report(that, cause); 2431 result = that.type = types.createErrorType(pt()); 2432 return; 2433 } finally { 2434 localEnv.info.scope.leave(); 2435 if (needsRecovery) { 2436 attribTree(that, env, recoveryInfo); 2437 } 2438 } 2439 } 2440 //where 2441 Types.MapVisitor<DiagnosticPosition> targetChecker = new Types.MapVisitor<DiagnosticPosition>() { 2442 2443 @Override 2444 public Type visitClassType(ClassType t, DiagnosticPosition pos) { 2445 return t.isCompound() ? 2446 visitIntersectionClassType((IntersectionClassType)t, pos) : t; 2447 } 2448 2449 public Type visitIntersectionClassType(IntersectionClassType ict, DiagnosticPosition pos) { 2450 Symbol desc = types.findDescriptorSymbol(makeNotionalInterface(ict)); 2451 Type target = null; 2452 for (Type bound : ict.getExplicitComponents()) { 2453 TypeSymbol boundSym = bound.tsym; 2454 if (types.isFunctionalInterface(boundSym) && 2455 types.findDescriptorSymbol(boundSym) == desc) { 2456 target = bound; 2457 } else if (!boundSym.isInterface() || (boundSym.flags() & ANNOTATION) != 0) { 2458 //bound must be an interface 2459 reportIntersectionError(pos, "not.an.intf.component", boundSym); 2460 } 2461 } 2462 return target != null ? 2463 target : 2464 ict.getExplicitComponents().head; //error recovery 2465 } 2466 2467 private TypeSymbol makeNotionalInterface(IntersectionClassType ict) { 2468 ListBuffer<Type> targs = ListBuffer.lb(); 2469 ListBuffer<Type> supertypes = ListBuffer.lb(); 2470 for (Type i : ict.interfaces_field) { 2471 if (i.isParameterized()) { 2472 targs.appendList(i.tsym.type.allparams()); 2473 } 2474 supertypes.append(i.tsym.type); 2475 } 2476 IntersectionClassType notionalIntf = 2477 (IntersectionClassType)types.makeCompoundType(supertypes.toList()); 2478 notionalIntf.allparams_field = targs.toList(); 2479 notionalIntf.tsym.flags_field |= INTERFACE; 2480 return notionalIntf.tsym; 2481 } 2482 2483 private void reportIntersectionError(DiagnosticPosition pos, String key, Object... args) { 2484 resultInfo.checkContext.report(pos, diags.fragment("bad.intersection.target.for.functional.expr", 2485 diags.fragment(key, args))); 2486 } 2487 }; 2488 2489 private Type fallbackDescriptorType(JCExpression tree) { 2490 switch (tree.getTag()) { 2491 case LAMBDA: 2492 JCLambda lambda = (JCLambda)tree; 2493 List<Type> argtypes = List.nil(); 2494 for (JCVariableDecl param : lambda.params) { 2495 argtypes = param.vartype != null ? 2496 argtypes.append(param.vartype.type) : 2497 argtypes.append(syms.errType); 2498 } 2499 return new MethodType(argtypes, Type.recoveryType, 2500 List.of(syms.throwableType), syms.methodClass); 2501 case REFERENCE: 2502 return new MethodType(List.<Type>nil(), Type.recoveryType, 2503 List.of(syms.throwableType), syms.methodClass); 2504 default: 2505 Assert.error("Cannot get here!"); 2506 } 2507 return null; 2508 } 2509 2510 private void checkAccessibleTypes(final DiagnosticPosition pos, final Env<AttrContext> env, 2511 final InferenceContext inferenceContext, final Type... ts) { 2512 checkAccessibleTypes(pos, env, inferenceContext, List.from(ts)); 2513 } 2514 2515 private void checkAccessibleTypes(final DiagnosticPosition pos, final Env<AttrContext> env, 2516 final InferenceContext inferenceContext, final List<Type> ts) { 2517 if (inferenceContext.free(ts)) { 2518 inferenceContext.addFreeTypeListener(ts, new FreeTypeListener() { 2519 @Override 2520 public void typesInferred(InferenceContext inferenceContext) { 2521 checkAccessibleTypes(pos, env, inferenceContext, inferenceContext.asInstTypes(ts)); 2522 } 2523 }); 2524 } else { 2525 for (Type t : ts) { 2526 rs.checkAccessibleType(env, t); 2527 } 2528 } 2529 } 2530 2531 /** 2532 * Lambda/method reference have a special check context that ensures 2533 * that i.e. a lambda return type is compatible with the expected 2534 * type according to both the inherited context and the assignment 2535 * context. 2536 */ 2537 class FunctionalReturnContext extends Check.NestedCheckContext { 2538 2539 FunctionalReturnContext(CheckContext enclosingContext) { 2540 super(enclosingContext); 2541 } 2542 2543 @Override 2544 public boolean compatible(Type found, Type req, Warner warn) { 2545 //return type must be compatible in both current context and assignment context 2546 return chk.basicHandler.compatible(found, inferenceContext().asFree(req), warn); 2547 } 2548 2549 @Override 2550 public void report(DiagnosticPosition pos, JCDiagnostic details) { 2551 enclosingContext.report(pos, diags.fragment("incompatible.ret.type.in.lambda", details)); 2552 } 2553 } 2554 2555 class ExpressionLambdaReturnContext extends FunctionalReturnContext { 2556 2557 JCExpression expr; 2558 2559 ExpressionLambdaReturnContext(JCExpression expr, CheckContext enclosingContext) { 2560 super(enclosingContext); 2561 this.expr = expr; 2562 } 2563 2564 @Override 2565 public boolean compatible(Type found, Type req, Warner warn) { 2566 //a void return is compatible with an expression statement lambda 2567 return TreeInfo.isExpressionStatement(expr) && req.hasTag(VOID) || 2568 super.compatible(found, req, warn); 2569 } 2570 } 2571 2572 /** 2573 * Lambda compatibility. Check that given return types, thrown types, parameter types 2574 * are compatible with the expected functional interface descriptor. This means that: 2575 * (i) parameter types must be identical to those of the target descriptor; (ii) return 2576 * types must be compatible with the return type of the expected descriptor; 2577 * (iii) thrown types must be 'included' in the thrown types list of the expected 2578 * descriptor. 2579 */ 2580 private void checkLambdaCompatible(JCLambda tree, Type descriptor, CheckContext checkContext, boolean speculativeAttr) { 2581 Type returnType = checkContext.inferenceContext().asFree(descriptor.getReturnType()); 2582 2583 //return values have already been checked - but if lambda has no return 2584 //values, we must ensure that void/value compatibility is correct; 2585 //this amounts at checking that, if a lambda body can complete normally, 2586 //the descriptor's return type must be void 2587 if (tree.getBodyKind() == JCLambda.BodyKind.STATEMENT && tree.canCompleteNormally && 2588 !returnType.hasTag(VOID) && returnType != Type.recoveryType) { 2589 checkContext.report(tree, diags.fragment("incompatible.ret.type.in.lambda", 2590 diags.fragment("missing.ret.val", returnType))); 2591 } 2592 2593 List<Type> argTypes = checkContext.inferenceContext().asFree(descriptor.getParameterTypes()); 2594 if (!types.isSameTypes(argTypes, TreeInfo.types(tree.params))) { 2595 checkContext.report(tree, diags.fragment("incompatible.arg.types.in.lambda")); 2596 } 2597 2598 if (!speculativeAttr) { 2599 List<Type> thrownTypes = checkContext.inferenceContext().asFree(descriptor.getThrownTypes()); 2600 if (chk.unhandled(tree.inferredThrownTypes == null ? List.<Type>nil() : tree.inferredThrownTypes, thrownTypes).nonEmpty()) { 2601 log.error(tree, "incompatible.thrown.types.in.lambda", tree.inferredThrownTypes); 2602 } 2603 } 2604 } 2605 2606 private Env<AttrContext> lambdaEnv(JCLambda that, Env<AttrContext> env) { 2607 Env<AttrContext> lambdaEnv; 2608 Symbol owner = env.info.scope.owner; 2609 if (owner.kind == VAR && owner.owner.kind == TYP) { 2610 //field initializer 2611 lambdaEnv = env.dup(that, env.info.dup(env.info.scope.dupUnshared())); 2612 lambdaEnv.info.scope.owner = 2613 new MethodSymbol(0, names.empty, null, 2614 env.info.scope.owner); 2615 } else { 2616 lambdaEnv = env.dup(that, env.info.dup(env.info.scope.dup())); 2617 } 2618 return lambdaEnv; 2619 } 2620 2621 @Override 2622 public void visitReference(final JCMemberReference that) { 2623 if (pt().isErroneous() || (pt().hasTag(NONE) && pt() != Type.recoveryType)) { 2624 if (pt().hasTag(NONE)) { 2625 //method reference only allowed in assignment or method invocation/cast context 2626 log.error(that.pos(), "unexpected.mref"); 2627 } 2628 result = that.type = types.createErrorType(pt()); 2629 return; 2630 } 2631 final Env<AttrContext> localEnv = env.dup(that); 2632 try { 2633 //attribute member reference qualifier - if this is a constructor 2634 //reference, the expected kind must be a type 2635 Type exprType = attribTree(that.expr, env, memberReferenceQualifierResult(that)); 2636 2637 if (that.getMode() == JCMemberReference.ReferenceMode.NEW) { 2638 exprType = chk.checkConstructorRefType(that.expr, exprType); 2639 } 2640 2641 if (exprType.isErroneous()) { 2642 //if the qualifier expression contains problems, 2643 //give up attribution of method reference 2644 result = that.type = exprType; 2645 return; 2646 } 2647 2648 if (TreeInfo.isStaticSelector(that.expr, names)) { 2649 //if the qualifier is a type, validate it; raw warning check is 2650 //omitted as we don't know at this stage as to whether this is a 2651 //raw selector (because of inference) 2652 chk.validate(that.expr, env, false); 2653 } 2654 2655 //attrib type-arguments 2656 List<Type> typeargtypes = List.nil(); 2657 if (that.typeargs != null) { 2658 typeargtypes = attribTypes(that.typeargs, localEnv); 2659 } 2660 2661 Type target; 2662 Type desc; 2663 if (pt() != Type.recoveryType) { 2664 target = targetChecker.visit(pt(), that); 2665 desc = types.findDescriptorType(target); 2666 chk.checkFunctionalInterface(that, target); 2667 } else { 2668 target = Type.recoveryType; 2669 desc = fallbackDescriptorType(that); 2670 } 2671 2672 setFunctionalInfo(that, pt(), desc, target, resultInfo.checkContext.inferenceContext()); 2673 List<Type> argtypes = desc.getParameterTypes(); 2674 2675 Pair<Symbol, Resolve.ReferenceLookupHelper> refResult = 2676 rs.resolveMemberReference(that.pos(), localEnv, that, 2677 that.expr.type, that.name, argtypes, typeargtypes, true, rs.resolveMethodCheck); 2678 2679 Symbol refSym = refResult.fst; 2680 Resolve.ReferenceLookupHelper lookupHelper = refResult.snd; 2681 2682 if (refSym.kind != MTH) { 2683 boolean targetError; 2684 switch (refSym.kind) { 2685 case ABSENT_MTH: 2686 targetError = false; 2687 break; 2688 case WRONG_MTH: 2689 case WRONG_MTHS: 2690 case AMBIGUOUS: 2691 case HIDDEN: 2692 case STATICERR: 2693 case MISSING_ENCL: 2694 targetError = true; 2695 break; 2696 default: 2697 Assert.error("unexpected result kind " + refSym.kind); 2698 targetError = false; 2699 } 2700 2701 JCDiagnostic detailsDiag = ((Resolve.ResolveError)refSym).getDiagnostic(JCDiagnostic.DiagnosticType.FRAGMENT, 2702 that, exprType.tsym, exprType, that.name, argtypes, typeargtypes); 2703 2704 JCDiagnostic.DiagnosticType diagKind = targetError ? 2705 JCDiagnostic.DiagnosticType.FRAGMENT : JCDiagnostic.DiagnosticType.ERROR; 2706 2707 JCDiagnostic diag = diags.create(diagKind, log.currentSource(), that, 2708 "invalid.mref", Kinds.kindName(that.getMode()), detailsDiag); 2709 2710 if (targetError && target == Type.recoveryType) { 2711 //a target error doesn't make sense during recovery stage 2712 //as we don't know what actual parameter types are 2713 result = that.type = target; 2714 return; 2715 } else { 2716 if (targetError) { 2717 resultInfo.checkContext.report(that, diag); 2718 } else { 2719 log.report(diag); 2720 } 2721 result = that.type = types.createErrorType(target); 2722 return; 2723 } 2724 } 2725 2726 that.sym = refSym.baseSymbol(); 2727 that.kind = lookupHelper.referenceKind(that.sym); 2728 that.ownerAccessible = rs.isAccessible(localEnv, that.sym.enclClass()); 2729 2730 if (desc.getReturnType() == Type.recoveryType) { 2731 // stop here 2732 result = that.type = target; 2733 return; 2734 } 2735 2736 if (resultInfo.checkContext.deferredAttrContext().mode == AttrMode.CHECK) { 2737 2738 if (that.getMode() == ReferenceMode.INVOKE && 2739 TreeInfo.isStaticSelector(that.expr, names) && 2740 that.kind.isUnbound() && 2741 !desc.getParameterTypes().head.isParameterized()) { 2742 chk.checkRaw(that.expr, localEnv); 2743 } 2744 2745 if (!that.kind.isUnbound() && 2746 that.getMode() == ReferenceMode.INVOKE && 2747 TreeInfo.isStaticSelector(that.expr, names) && 2748 !that.sym.isStatic()) { 2749 log.error(that.expr.pos(), "invalid.mref", Kinds.kindName(that.getMode()), 2750 diags.fragment("non-static.cant.be.ref", Kinds.kindName(refSym), refSym)); 2751 result = that.type = types.createErrorType(target); 2752 return; 2753 } 2754 2755 if (that.kind.isUnbound() && 2756 that.getMode() == ReferenceMode.INVOKE && 2757 TreeInfo.isStaticSelector(that.expr, names) && 2758 that.sym.isStatic()) { 2759 log.error(that.expr.pos(), "invalid.mref", Kinds.kindName(that.getMode()), 2760 diags.fragment("static.method.in.unbound.lookup", Kinds.kindName(refSym), refSym)); 2761 result = that.type = types.createErrorType(target); 2762 return; 2763 } 2764 2765 if (that.sym.isStatic() && TreeInfo.isStaticSelector(that.expr, names) && 2766 exprType.getTypeArguments().nonEmpty()) { 2767 //static ref with class type-args 2768 log.error(that.expr.pos(), "invalid.mref", Kinds.kindName(that.getMode()), 2769 diags.fragment("static.mref.with.targs")); 2770 result = that.type = types.createErrorType(target); 2771 return; 2772 } 2773 2774 if (that.sym.isStatic() && !TreeInfo.isStaticSelector(that.expr, names) && 2775 !that.kind.isUnbound()) { 2776 //no static bound mrefs 2777 log.error(that.expr.pos(), "invalid.mref", Kinds.kindName(that.getMode()), 2778 diags.fragment("static.bound.mref")); 2779 result = that.type = types.createErrorType(target); 2780 return; 2781 } 2782 2783 if (!refSym.isStatic() && that.kind == JCMemberReference.ReferenceKind.SUPER) { 2784 // Check that super-qualified symbols are not abstract (JLS) 2785 rs.checkNonAbstract(that.pos(), that.sym); 2786 } 2787 } 2788 2789 that.sym = refSym.baseSymbol(); 2790 that.kind = lookupHelper.referenceKind(that.sym); 2791 2792 ResultInfo checkInfo = 2793 resultInfo.dup(newMethodTemplate( 2794 desc.getReturnType().hasTag(VOID) ? Type.noType : desc.getReturnType(), 2795 lookupHelper.argtypes, 2796 typeargtypes)); 2797 2798 Type refType = checkId(that, lookupHelper.site, refSym, localEnv, checkInfo); 2799 2800 if (!refType.isErroneous()) { 2801 refType = types.createMethodTypeWithReturn(refType, 2802 adjustMethodReturnType(lookupHelper.site, that.name, checkInfo.pt.getParameterTypes(), refType.getReturnType())); 2803 } 2804 2805 //go ahead with standard method reference compatibility check - note that param check 2806 //is a no-op (as this has been taken care during method applicability) 2807 boolean isSpeculativeRound = 2808 resultInfo.checkContext.deferredAttrContext().mode == DeferredAttr.AttrMode.SPECULATIVE; 2809 checkReferenceCompatible(that, desc, refType, resultInfo.checkContext, isSpeculativeRound); 2810 if (!isSpeculativeRound) { 2811 checkAccessibleTypes(that, localEnv, resultInfo.checkContext.inferenceContext(), desc, target); 2812 } 2813 result = check(that, target, VAL, resultInfo); 2814 } catch (Types.FunctionDescriptorLookupError ex) { 2815 JCDiagnostic cause = ex.getDiagnostic(); 2816 resultInfo.checkContext.report(that, cause); 2817 result = that.type = types.createErrorType(pt()); 2818 return; 2819 } 2820 } 2821 //where 2822 ResultInfo memberReferenceQualifierResult(JCMemberReference tree) { 2823 //if this is a constructor reference, the expected kind must be a type 2824 return new ResultInfo(tree.getMode() == ReferenceMode.INVOKE ? VAL | TYP : TYP, Type.noType); 2825 } 2826 2827 2828 @SuppressWarnings("fallthrough") 2829 void checkReferenceCompatible(JCMemberReference tree, Type descriptor, Type refType, CheckContext checkContext, boolean speculativeAttr) { 2830 Type returnType = checkContext.inferenceContext().asFree(descriptor.getReturnType()); 2831 2832 Type resType; 2833 switch (tree.getMode()) { 2834 case NEW: 2835 if (!tree.expr.type.isRaw()) { 2836 resType = tree.expr.type; 2837 break; 2838 } 2839 default: 2840 resType = refType.getReturnType(); 2841 } 2842 2843 Type incompatibleReturnType = resType; 2844 2845 if (returnType.hasTag(VOID)) { 2846 incompatibleReturnType = null; 2847 } 2848 2849 if (!returnType.hasTag(VOID) && !resType.hasTag(VOID)) { 2850 if (resType.isErroneous() || 2851 new FunctionalReturnContext(checkContext).compatible(resType, returnType, types.noWarnings)) { 2852 incompatibleReturnType = null; 2853 } 2854 } 2855 2856 if (incompatibleReturnType != null) { 2857 checkContext.report(tree, diags.fragment("incompatible.ret.type.in.mref", 2858 diags.fragment("inconvertible.types", resType, descriptor.getReturnType()))); 2859 } 2860 2861 if (!speculativeAttr) { 2862 List<Type> thrownTypes = checkContext.inferenceContext().asFree(descriptor.getThrownTypes()); 2863 if (chk.unhandled(refType.getThrownTypes(), thrownTypes).nonEmpty()) { 2864 log.error(tree, "incompatible.thrown.types.in.mref", refType.getThrownTypes()); 2865 } 2866 } 2867 } 2868 2869 /** 2870 * Set functional type info on the underlying AST. Note: as the target descriptor 2871 * might contain inference variables, we might need to register an hook in the 2872 * current inference context. 2873 */ 2874 private void setFunctionalInfo(final JCFunctionalExpression fExpr, final Type pt, 2875 final Type descriptorType, final Type primaryTarget, InferenceContext inferenceContext) { 2876 if (inferenceContext.free(descriptorType)) { 2877 inferenceContext.addFreeTypeListener(List.of(pt, descriptorType), new FreeTypeListener() { 2878 public void typesInferred(InferenceContext inferenceContext) { 2879 setFunctionalInfo(fExpr, pt, inferenceContext.asInstType(descriptorType), 2880 inferenceContext.asInstType(primaryTarget), inferenceContext); 2881 } 2882 }); 2883 } else { 2884 ListBuffer<TypeSymbol> targets = ListBuffer.lb(); 2885 if (pt.hasTag(CLASS)) { 2886 if (pt.isCompound()) { 2887 targets.append(primaryTarget.tsym); //this goes first 2888 for (Type t : ((IntersectionClassType)pt()).interfaces_field) { 2889 if (t != primaryTarget) { 2890 targets.append(t.tsym); 2891 } 2892 } 2893 } else { 2894 targets.append(pt.tsym); 2895 } 2896 } 2897 fExpr.targets = targets.toList(); 2898 fExpr.descriptorType = descriptorType; 2899 } 2900 } 2901 2902 public void visitParens(JCParens tree) { 2903 Type owntype = attribTree(tree.expr, env, resultInfo); 2904 result = check(tree, owntype, pkind(), resultInfo); 2905 Symbol sym = TreeInfo.symbol(tree); 2906 if (sym != null && (sym.kind&(TYP|PCK)) != 0) 2907 log.error(tree.pos(), "illegal.start.of.type"); 2908 } 2909 2910 public void visitAssign(JCAssign tree) { 2911 Type owntype = attribTree(tree.lhs, env.dup(tree), varInfo); 2912 Type capturedType = capture(owntype); 2913 attribExpr(tree.rhs, env, owntype); 2914 result = check(tree, capturedType, VAL, resultInfo); 2915 } 2916 2917 public void visitAssignop(JCAssignOp tree) { 2918 // Attribute arguments. 2919 Type owntype = attribTree(tree.lhs, env, varInfo); 2920 Type operand = attribExpr(tree.rhs, env); 2921 // Find operator. 2922 Symbol operator = tree.operator = rs.resolveBinaryOperator( 2923 tree.pos(), tree.getTag().noAssignOp(), env, 2924 owntype, operand); 2925 2926 if (operator.kind == MTH && 2927 !owntype.isErroneous() && 2928 !operand.isErroneous()) { 2929 chk.checkOperator(tree.pos(), 2930 (OperatorSymbol)operator, 2931 tree.getTag().noAssignOp(), 2932 owntype, 2933 operand); 2934 chk.checkDivZero(tree.rhs.pos(), operator, operand); 2935 chk.checkCastable(tree.rhs.pos(), 2936 operator.type.getReturnType(), 2937 owntype); 2938 } 2939 result = check(tree, owntype, VAL, resultInfo); 2940 } 2941 2942 public void visitUnary(JCUnary tree) { 2943 // Attribute arguments. 2944 Type argtype = (tree.getTag().isIncOrDecUnaryOp()) 2945 ? attribTree(tree.arg, env, varInfo) 2946 : chk.checkNonVoid(tree.arg.pos(), attribExpr(tree.arg, env)); 2947 2948 // Find operator. 2949 Symbol operator = tree.operator = 2950 rs.resolveUnaryOperator(tree.pos(), tree.getTag(), env, argtype); 2951 2952 Type owntype = types.createErrorType(tree.type); 2953 if (operator.kind == MTH && 2954 !argtype.isErroneous()) { 2955 owntype = (tree.getTag().isIncOrDecUnaryOp()) 2956 ? tree.arg.type 2957 : operator.type.getReturnType(); 2958 int opc = ((OperatorSymbol)operator).opcode; 2959 2960 // If the argument is constant, fold it. 2961 if (argtype.constValue() != null) { 2962 Type ctype = cfolder.fold1(opc, argtype); 2963 if (ctype != null) { 2964 owntype = cfolder.coerce(ctype, owntype); 2965 2966 // Remove constant types from arguments to 2967 // conserve space. The parser will fold concatenations 2968 // of string literals; the code here also 2969 // gets rid of intermediate results when some of the 2970 // operands are constant identifiers. 2971 if (tree.arg.type.tsym == syms.stringType.tsym) { 2972 tree.arg.type = syms.stringType; 2973 } 2974 } 2975 } 2976 } 2977 result = check(tree, owntype, VAL, resultInfo); 2978 } 2979 2980 public void visitBinary(JCBinary tree) { 2981 // Attribute arguments. 2982 Type left = chk.checkNonVoid(tree.lhs.pos(), attribExpr(tree.lhs, env)); 2983 Type right = chk.checkNonVoid(tree.lhs.pos(), attribExpr(tree.rhs, env)); 2984 2985 // Find operator. 2986 Symbol operator = tree.operator = 2987 rs.resolveBinaryOperator(tree.pos(), tree.getTag(), env, left, right); 2988 2989 Type owntype = types.createErrorType(tree.type); 2990 if (operator.kind == MTH && 2991 !left.isErroneous() && 2992 !right.isErroneous()) { 2993 owntype = operator.type.getReturnType(); 2994 int opc = chk.checkOperator(tree.lhs.pos(), 2995 (OperatorSymbol)operator, 2996 tree.getTag(), 2997 left, 2998 right); 2999 3000 // If both arguments are constants, fold them. 3001 if (left.constValue() != null && right.constValue() != null) { 3002 Type ctype = cfolder.fold2(opc, left, right); 3003 if (ctype != null) { 3004 owntype = cfolder.coerce(ctype, owntype); 3005 3006 // Remove constant types from arguments to 3007 // conserve space. The parser will fold concatenations 3008 // of string literals; the code here also 3009 // gets rid of intermediate results when some of the 3010 // operands are constant identifiers. 3011 if (tree.lhs.type.tsym == syms.stringType.tsym) { 3012 tree.lhs.type = syms.stringType; 3013 } 3014 if (tree.rhs.type.tsym == syms.stringType.tsym) { 3015 tree.rhs.type = syms.stringType; 3016 } 3017 } 3018 } 3019 3020 // Check that argument types of a reference ==, != are 3021 // castable to each other, (JLS???). 3022 if ((opc == ByteCodes.if_acmpeq || opc == ByteCodes.if_acmpne)) { 3023 if (!types.isCastable(left, right, new Warner(tree.pos()))) { 3024 log.error(tree.pos(), "incomparable.types", left, right); 3025 } 3026 } 3027 3028 chk.checkDivZero(tree.rhs.pos(), operator, right); 3029 } 3030 result = check(tree, owntype, VAL, resultInfo); 3031 } 3032 3033 public void visitTypeCast(final JCTypeCast tree) { 3034 Type clazztype = attribType(tree.clazz, env); 3035 chk.validate(tree.clazz, env, false); 3036 //a fresh environment is required for 292 inference to work properly --- 3037 //see Infer.instantiatePolymorphicSignatureInstance() 3038 Env<AttrContext> localEnv = env.dup(tree); 3039 //should we propagate the target type? 3040 final ResultInfo castInfo; 3041 JCExpression expr = TreeInfo.skipParens(tree.expr); 3042 boolean isPoly = expr.hasTag(LAMBDA) || expr.hasTag(REFERENCE); 3043 if (isPoly) { 3044 //expression is a poly - we need to propagate target type info 3045 castInfo = new ResultInfo(VAL, clazztype, new Check.NestedCheckContext(resultInfo.checkContext) { 3046 @Override 3047 public boolean compatible(Type found, Type req, Warner warn) { 3048 return types.isCastable(found, req, warn); 3049 } 3050 }); 3051 } else { 3052 //standalone cast - target-type info is not propagated 3053 castInfo = unknownExprInfo; 3054 } 3055 Type exprtype = attribTree(tree.expr, localEnv, castInfo); 3056 Type owntype = isPoly ? clazztype : chk.checkCastable(tree.expr.pos(), exprtype, clazztype); 3057 if (exprtype.constValue() != null) 3058 owntype = cfolder.coerce(exprtype, owntype); 3059 result = check(tree, capture(owntype), VAL, resultInfo); 3060 if (!isPoly) 3061 chk.checkRedundantCast(localEnv, tree); 3062 } 3063 3064 public void visitTypeTest(JCInstanceOf tree) { 3065 Type exprtype = chk.checkNullOrRefType( 3066 tree.expr.pos(), attribExpr(tree.expr, env)); 3067 Type clazztype = chk.checkReifiableReferenceType( 3068 tree.clazz.pos(), attribType(tree.clazz, env)); 3069 chk.validate(tree.clazz, env, false); 3070 chk.checkCastable(tree.expr.pos(), exprtype, clazztype); 3071 result = check(tree, syms.booleanType, VAL, resultInfo); 3072 } 3073 3074 public void visitIndexed(JCArrayAccess tree) { 3075 Type owntype = types.createErrorType(tree.type); 3076 Type atype = attribExpr(tree.indexed, env); 3077 attribExpr(tree.index, env, syms.intType); 3078 if (types.isArray(atype)) 3079 owntype = types.elemtype(atype); 3080 else if (!atype.hasTag(ERROR)) 3081 log.error(tree.pos(), "array.req.but.found", atype); 3082 if ((pkind() & VAR) == 0) owntype = capture(owntype); 3083 result = check(tree, owntype, VAR, resultInfo); 3084 } 3085 3086 public void visitIdent(JCIdent tree) { 3087 Symbol sym; 3088 3089 // Find symbol 3090 if (pt().hasTag(METHOD) || pt().hasTag(FORALL)) { 3091 // If we are looking for a method, the prototype `pt' will be a 3092 // method type with the type of the call's arguments as parameters. 3093 env.info.pendingResolutionPhase = null; 3094 sym = rs.resolveMethod(tree.pos(), env, tree.name, pt().getParameterTypes(), pt().getTypeArguments()); 3095 } else if (tree.sym != null && tree.sym.kind != VAR) { 3096 sym = tree.sym; 3097 } else { 3098 sym = rs.resolveIdent(tree.pos(), env, tree.name, pkind()); 3099 } 3100 tree.sym = sym; 3101 3102 // (1) Also find the environment current for the class where 3103 // sym is defined (`symEnv'). 3104 // Only for pre-tiger versions (1.4 and earlier): 3105 // (2) Also determine whether we access symbol out of an anonymous 3106 // class in a this or super call. This is illegal for instance 3107 // members since such classes don't carry a this$n link. 3108 // (`noOuterThisPath'). 3109 Env<AttrContext> symEnv = env; 3110 boolean noOuterThisPath = false; 3111 if (env.enclClass.sym.owner.kind != PCK && // we are in an inner class 3112 (sym.kind & (VAR | MTH | TYP)) != 0 && 3113 sym.owner.kind == TYP && 3114 tree.name != names._this && tree.name != names._super) { 3115 3116 // Find environment in which identifier is defined. 3117 while (symEnv.outer != null && 3118 !sym.isMemberOf(symEnv.enclClass.sym, types)) { 3119 if ((symEnv.enclClass.sym.flags() & NOOUTERTHIS) != 0) 3120 noOuterThisPath = !allowAnonOuterThis; 3121 symEnv = symEnv.outer; 3122 } 3123 } 3124 3125 // If symbol is a variable, ... 3126 if (sym.kind == VAR) { 3127 VarSymbol v = (VarSymbol)sym; 3128 3129 // ..., evaluate its initializer, if it has one, and check for 3130 // illegal forward reference. 3131 checkInit(tree, env, v, false); 3132 3133 // If we are expecting a variable (as opposed to a value), check 3134 // that the variable is assignable in the current environment. 3135 if (pkind() == VAR) 3136 checkAssignable(tree.pos(), v, null, env); 3137 } 3138 3139 // In a constructor body, 3140 // if symbol is a field or instance method, check that it is 3141 // not accessed before the supertype constructor is called. 3142 if ((symEnv.info.isSelfCall || noOuterThisPath) && 3143 (sym.kind & (VAR | MTH)) != 0 && 3144 sym.owner.kind == TYP && 3145 (sym.flags() & STATIC) == 0) { 3146 chk.earlyRefError(tree.pos(), sym.kind == VAR ? sym : thisSym(tree.pos(), env)); 3147 } 3148 Env<AttrContext> env1 = env; 3149 if (sym.kind != ERR && sym.kind != TYP && sym.owner != null && sym.owner != env1.enclClass.sym) { 3150 // If the found symbol is inaccessible, then it is 3151 // accessed through an enclosing instance. Locate this 3152 // enclosing instance: 3153 while (env1.outer != null && !rs.isAccessible(env, env1.enclClass.sym.type, sym)) 3154 env1 = env1.outer; 3155 } 3156 result = checkId(tree, env1.enclClass.sym.type, sym, env, resultInfo); 3157 } 3158 3159 public void visitSelect(JCFieldAccess tree) { 3160 // Determine the expected kind of the qualifier expression. 3161 int skind = 0; 3162 if (tree.name == names._this || tree.name == names._super || 3163 tree.name == names._class) 3164 { 3165 skind = TYP; 3166 } else { 3167 if ((pkind() & PCK) != 0) skind = skind | PCK; 3168 if ((pkind() & TYP) != 0) skind = skind | TYP | PCK; 3169 if ((pkind() & (VAL | MTH)) != 0) skind = skind | VAL | TYP; 3170 } 3171 3172 // Attribute the qualifier expression, and determine its symbol (if any). 3173 Type site = attribTree(tree.selected, env, new ResultInfo(skind, Infer.anyPoly)); 3174 if ((pkind() & (PCK | TYP)) == 0) 3175 site = capture(site); // Capture field access 3176 3177 // don't allow T.class T[].class, etc 3178 if (skind == TYP) { 3179 Type elt = site; 3180 while (elt.hasTag(ARRAY)) 3181 elt = ((ArrayType)elt).elemtype; 3182 if (elt.hasTag(TYPEVAR)) { 3183 log.error(tree.pos(), "type.var.cant.be.deref"); 3184 result = types.createErrorType(tree.type); 3185 return; 3186 } 3187 } 3188 3189 // If qualifier symbol is a type or `super', assert `selectSuper' 3190 // for the selection. This is relevant for determining whether 3191 // protected symbols are accessible. 3192 Symbol sitesym = TreeInfo.symbol(tree.selected); 3193 boolean selectSuperPrev = env.info.selectSuper; 3194 env.info.selectSuper = 3195 sitesym != null && 3196 sitesym.name == names._super; 3197 3198 // Determine the symbol represented by the selection. 3199 env.info.pendingResolutionPhase = null; 3200 Symbol sym = selectSym(tree, sitesym, site, env, resultInfo); 3201 if (sym.exists() && !isType(sym) && (pkind() & (PCK | TYP)) != 0) { 3202 site = capture(site); 3203 sym = selectSym(tree, sitesym, site, env, resultInfo); 3204 } 3205 boolean varArgs = env.info.lastResolveVarargs(); 3206 tree.sym = sym; 3207 3208 if (site.hasTag(TYPEVAR) && !isType(sym) && sym.kind != ERR) { 3209 while (site.hasTag(TYPEVAR)) site = site.getUpperBound(); 3210 site = capture(site); 3211 } 3212 3213 // If that symbol is a variable, ... 3214 if (sym.kind == VAR) { 3215 VarSymbol v = (VarSymbol)sym; 3216 3217 // ..., evaluate its initializer, if it has one, and check for 3218 // illegal forward reference. 3219 checkInit(tree, env, v, true); 3220 3221 // If we are expecting a variable (as opposed to a value), check 3222 // that the variable is assignable in the current environment. 3223 if (pkind() == VAR) 3224 checkAssignable(tree.pos(), v, tree.selected, env); 3225 } 3226 3227 if (sitesym != null && 3228 sitesym.kind == VAR && 3229 ((VarSymbol)sitesym).isResourceVariable() && 3230 sym.kind == MTH && 3231 sym.name.equals(names.close) && 3232 sym.overrides(syms.autoCloseableClose, sitesym.type.tsym, types, true) && 3233 env.info.lint.isEnabled(LintCategory.TRY)) { 3234 log.warning(LintCategory.TRY, tree, "try.explicit.close.call"); 3235 } 3236 3237 // Disallow selecting a type from an expression 3238 if (isType(sym) && (sitesym==null || (sitesym.kind&(TYP|PCK)) == 0)) { 3239 tree.type = check(tree.selected, pt(), 3240 sitesym == null ? VAL : sitesym.kind, new ResultInfo(TYP|PCK, pt())); 3241 } 3242 3243 if (isType(sitesym)) { 3244 if (sym.name == names._this) { 3245 // If `C' is the currently compiled class, check that 3246 // C.this' does not appear in a call to a super(...) 3247 if (env.info.isSelfCall && 3248 site.tsym == env.enclClass.sym) { 3249 chk.earlyRefError(tree.pos(), sym); 3250 } 3251 } else { 3252 // Check if type-qualified fields or methods are static (JLS) 3253 if ((sym.flags() & STATIC) == 0 && 3254 !env.next.tree.hasTag(REFERENCE) && 3255 sym.name != names._super && 3256 (sym.kind == VAR || sym.kind == MTH)) { 3257 rs.accessBase(rs.new StaticError(sym), 3258 tree.pos(), site, sym.name, true); 3259 } 3260 } 3261 } else if (sym.kind != ERR && (sym.flags() & STATIC) != 0 && sym.name != names._class) { 3262 // If the qualified item is not a type and the selected item is static, report 3263 // a warning. Make allowance for the class of an array type e.g. Object[].class) 3264 chk.warnStatic(tree, "static.not.qualified.by.type", Kinds.kindName(sym.kind), sym.owner); 3265 } 3266 3267 // If we are selecting an instance member via a `super', ... 3268 if (env.info.selectSuper && (sym.flags() & STATIC) == 0) { 3269 3270 // Check that super-qualified symbols are not abstract (JLS) 3271 rs.checkNonAbstract(tree.pos(), sym); 3272 3273 if (site.isRaw()) { 3274 // Determine argument types for site. 3275 Type site1 = types.asSuper(env.enclClass.sym.type, site.tsym); 3276 if (site1 != null) site = site1; 3277 } 3278 } 3279 3280 env.info.selectSuper = selectSuperPrev; 3281 result = checkId(tree, site, sym, env, resultInfo); 3282 } 3283 //where 3284 /** Determine symbol referenced by a Select expression, 3285 * 3286 * @param tree The select tree. 3287 * @param site The type of the selected expression, 3288 * @param env The current environment. 3289 * @param resultInfo The current result. 3290 */ 3291 private Symbol selectSym(JCFieldAccess tree, 3292 Symbol location, 3293 Type site, 3294 Env<AttrContext> env, 3295 ResultInfo resultInfo) { 3296 DiagnosticPosition pos = tree.pos(); 3297 Name name = tree.name; 3298 switch (site.getTag()) { 3299 case PACKAGE: 3300 return rs.accessBase( 3301 rs.findIdentInPackage(env, site.tsym, name, resultInfo.pkind), 3302 pos, location, site, name, true); 3303 case ARRAY: 3304 case CLASS: 3305 if (resultInfo.pt.hasTag(METHOD) || resultInfo.pt.hasTag(FORALL)) { 3306 return rs.resolveQualifiedMethod( 3307 pos, env, location, site, name, resultInfo.pt.getParameterTypes(), resultInfo.pt.getTypeArguments()); 3308 } else if (name == names._this || name == names._super) { 3309 return rs.resolveSelf(pos, env, site.tsym, name); 3310 } else if (name == names._class) { 3311 // In this case, we have already made sure in 3312 // visitSelect that qualifier expression is a type. 3313 Type t = syms.classType; 3314 List<Type> typeargs = allowGenerics 3315 ? List.of(types.erasure(site)) 3316 : List.<Type>nil(); 3317 t = new ClassType(t.getEnclosingType(), typeargs, t.tsym); 3318 return new VarSymbol( 3319 STATIC | PUBLIC | FINAL, names._class, t, site.tsym); 3320 } else { 3321 // We are seeing a plain identifier as selector. 3322 Symbol sym = rs.findIdentInType(env, site, name, resultInfo.pkind); 3323 if ((resultInfo.pkind & ERRONEOUS) == 0) 3324 sym = rs.accessBase(sym, pos, location, site, name, true); 3325 return sym; 3326 } 3327 case WILDCARD: 3328 throw new AssertionError(tree); 3329 case TYPEVAR: 3330 // Normally, site.getUpperBound() shouldn't be null. 3331 // It should only happen during memberEnter/attribBase 3332 // when determining the super type which *must* beac 3333 // done before attributing the type variables. In 3334 // other words, we are seeing this illegal program: 3335 // class B<T> extends A<T.foo> {} 3336 Symbol sym = (site.getUpperBound() != null) 3337 ? selectSym(tree, location, capture(site.getUpperBound()), env, resultInfo) 3338 : null; 3339 if (sym == null) { 3340 log.error(pos, "type.var.cant.be.deref"); 3341 return syms.errSymbol; 3342 } else { 3343 Symbol sym2 = (sym.flags() & Flags.PRIVATE) != 0 ? 3344 rs.new AccessError(env, site, sym) : 3345 sym; 3346 rs.accessBase(sym2, pos, location, site, name, true); 3347 return sym; 3348 } 3349 case ERROR: 3350 // preserve identifier names through errors 3351 return types.createErrorType(name, site.tsym, site).tsym; 3352 default: 3353 // The qualifier expression is of a primitive type -- only 3354 // .class is allowed for these. 3355 if (name == names._class) { 3356 // In this case, we have already made sure in Select that 3357 // qualifier expression is a type. 3358 Type t = syms.classType; 3359 Type arg = types.boxedClass(site).type; 3360 t = new ClassType(t.getEnclosingType(), List.of(arg), t.tsym); 3361 return new VarSymbol( 3362 STATIC | PUBLIC | FINAL, names._class, t, site.tsym); 3363 } else { 3364 log.error(pos, "cant.deref", site); 3365 return syms.errSymbol; 3366 } 3367 } 3368 } 3369 3370 /** Determine type of identifier or select expression and check that 3371 * (1) the referenced symbol is not deprecated 3372 * (2) the symbol's type is safe (@see checkSafe) 3373 * (3) if symbol is a variable, check that its type and kind are 3374 * compatible with the prototype and protokind. 3375 * (4) if symbol is an instance field of a raw type, 3376 * which is being assigned to, issue an unchecked warning if its 3377 * type changes under erasure. 3378 * (5) if symbol is an instance method of a raw type, issue an 3379 * unchecked warning if its argument types change under erasure. 3380 * If checks succeed: 3381 * If symbol is a constant, return its constant type 3382 * else if symbol is a method, return its result type 3383 * otherwise return its type. 3384 * Otherwise return errType. 3385 * 3386 * @param tree The syntax tree representing the identifier 3387 * @param site If this is a select, the type of the selected 3388 * expression, otherwise the type of the current class. 3389 * @param sym The symbol representing the identifier. 3390 * @param env The current environment. 3391 * @param resultInfo The expected result 3392 */ 3393 Type checkId(JCTree tree, 3394 Type site, 3395 Symbol sym, 3396 Env<AttrContext> env, 3397 ResultInfo resultInfo) { 3398 return (resultInfo.pt.hasTag(FORALL) || resultInfo.pt.hasTag(METHOD)) ? 3399 checkMethodId(tree, site, sym, env, resultInfo) : 3400 checkIdInternal(tree, site, sym, resultInfo.pt, env, resultInfo); 3401 } 3402 3403 Type checkMethodId(JCTree tree, 3404 Type site, 3405 Symbol sym, 3406 Env<AttrContext> env, 3407 ResultInfo resultInfo) { 3408 boolean isPolymorhicSignature = 3409 sym.kind == MTH && ((MethodSymbol)sym.baseSymbol()).isSignaturePolymorphic(types); 3410 return isPolymorhicSignature ? 3411 checkSigPolyMethodId(tree, site, sym, env, resultInfo) : 3412 checkMethodIdInternal(tree, site, sym, env, resultInfo); 3413 } 3414 3415 Type checkSigPolyMethodId(JCTree tree, 3416 Type site, 3417 Symbol sym, 3418 Env<AttrContext> env, 3419 ResultInfo resultInfo) { 3420 //recover original symbol for signature polymorphic methods 3421 checkMethodIdInternal(tree, site, sym.baseSymbol(), env, resultInfo); 3422 env.info.pendingResolutionPhase = Resolve.MethodResolutionPhase.BASIC; 3423 return sym.type; 3424 } 3425 3426 Type checkMethodIdInternal(JCTree tree, 3427 Type site, 3428 Symbol sym, 3429 Env<AttrContext> env, 3430 ResultInfo resultInfo) { 3431 Type pt = resultInfo.pt.map(deferredAttr.new RecoveryDeferredTypeMap(AttrMode.SPECULATIVE, sym, env.info.pendingResolutionPhase)); 3432 Type owntype = checkIdInternal(tree, site, sym, pt, env, resultInfo); 3433 resultInfo.pt.map(deferredAttr.new RecoveryDeferredTypeMap(AttrMode.CHECK, sym, env.info.pendingResolutionPhase)); 3434 return owntype; 3435 } 3436 3437 Type checkIdInternal(JCTree tree, 3438 Type site, 3439 Symbol sym, 3440 Type pt, 3441 Env<AttrContext> env, 3442 ResultInfo resultInfo) { 3443 if (pt.isErroneous()) { 3444 return types.createErrorType(site); 3445 } 3446 Type owntype; // The computed type of this identifier occurrence. 3447 switch (sym.kind) { 3448 case TYP: 3449 // For types, the computed type equals the symbol's type, 3450 // except for two situations: 3451 owntype = sym.type; 3452 if (owntype.hasTag(CLASS)) { 3453 chk.checkForBadAuxiliaryClassAccess(tree.pos(), env, (ClassSymbol)sym); 3454 Type ownOuter = owntype.getEnclosingType(); 3455 3456 // (a) If the symbol's type is parameterized, erase it 3457 // because no type parameters were given. 3458 // We recover generic outer type later in visitTypeApply. 3459 if (owntype.tsym.type.getTypeArguments().nonEmpty()) { 3460 owntype = types.erasure(owntype); 3461 } 3462 3463 // (b) If the symbol's type is an inner class, then 3464 // we have to interpret its outer type as a superclass 3465 // of the site type. Example: 3466 // 3467 // class Tree<A> { class Visitor { ... } } 3468 // class PointTree extends Tree<Point> { ... } 3469 // ...PointTree.Visitor... 3470 // 3471 // Then the type of the last expression above is 3472 // Tree<Point>.Visitor. 3473 else if (ownOuter.hasTag(CLASS) && site != ownOuter) { 3474 Type normOuter = site; 3475 if (normOuter.hasTag(CLASS)) { 3476 normOuter = types.asEnclosingSuper(site, ownOuter.tsym); 3477 if (site.isAnnotated()) { 3478 // Propagate any type annotations. 3479 // TODO: should asEnclosingSuper do this? 3480 // Note that the type annotations in site will be updated 3481 // by annotateType. Therefore, modify site instead 3482 // of creating a new AnnotatedType. 3483 ((AnnotatedType)site).underlyingType = normOuter; 3484 normOuter = site; 3485 } 3486 } 3487 if (normOuter == null) // perhaps from an import 3488 normOuter = types.erasure(ownOuter); 3489 if (normOuter != ownOuter) 3490 owntype = new ClassType( 3491 normOuter, List.<Type>nil(), owntype.tsym); 3492 } 3493 } 3494 break; 3495 case VAR: 3496 VarSymbol v = (VarSymbol)sym; 3497 // Test (4): if symbol is an instance field of a raw type, 3498 // which is being assigned to, issue an unchecked warning if 3499 // its type changes under erasure. 3500 if (allowGenerics && 3501 resultInfo.pkind == VAR && 3502 v.owner.kind == TYP && 3503 (v.flags() & STATIC) == 0 && 3504 (site.hasTag(CLASS) || site.hasTag(TYPEVAR))) { 3505 Type s = types.asOuterSuper(site, v.owner); 3506 if (s != null && 3507 s.isRaw() && 3508 !types.isSameType(v.type, v.erasure(types))) { 3509 chk.warnUnchecked(tree.pos(), 3510 "unchecked.assign.to.var", 3511 v, s); 3512 } 3513 } 3514 // The computed type of a variable is the type of the 3515 // variable symbol, taken as a member of the site type. 3516 owntype = (sym.owner.kind == TYP && 3517 sym.name != names._this && sym.name != names._super) 3518 ? types.memberType(site, sym) 3519 : sym.type; 3520 3521 // If the variable is a constant, record constant value in 3522 // computed type. 3523 if (v.getConstValue() != null && isStaticReference(tree)) 3524 owntype = owntype.constType(v.getConstValue()); 3525 3526 if (resultInfo.pkind == VAL) { 3527 owntype = capture(owntype); // capture "names as expressions" 3528 } 3529 break; 3530 case MTH: { 3531 owntype = checkMethod(site, sym, 3532 new ResultInfo(VAL, resultInfo.pt.getReturnType(), resultInfo.checkContext), 3533 env, TreeInfo.args(env.tree), resultInfo.pt.getParameterTypes(), 3534 resultInfo.pt.getTypeArguments()); 3535 break; 3536 } 3537 case PCK: case ERR: 3538 owntype = sym.type; 3539 break; 3540 default: 3541 throw new AssertionError("unexpected kind: " + sym.kind + 3542 " in tree " + tree); 3543 } 3544 3545 // Test (1): emit a `deprecation' warning if symbol is deprecated. 3546 // (for constructors, the error was given when the constructor was 3547 // resolved) 3548 3549 if (sym.name != names.init) { 3550 chk.checkDeprecated(tree.pos(), env.info.scope.owner, sym); 3551 chk.checkSunAPI(tree.pos(), sym); 3552 chk.checkProfile(tree.pos(), sym); 3553 } 3554 3555 // Test (3): if symbol is a variable, check that its type and 3556 // kind are compatible with the prototype and protokind. 3557 return check(tree, owntype, sym.kind, resultInfo); 3558 } 3559 3560 /** Check that variable is initialized and evaluate the variable's 3561 * initializer, if not yet done. Also check that variable is not 3562 * referenced before it is defined. 3563 * @param tree The tree making up the variable reference. 3564 * @param env The current environment. 3565 * @param v The variable's symbol. 3566 */ 3567 private void checkInit(JCTree tree, 3568 Env<AttrContext> env, 3569 VarSymbol v, 3570 boolean onlyWarning) { 3571 // System.err.println(v + " " + ((v.flags() & STATIC) != 0) + " " + 3572 // tree.pos + " " + v.pos + " " + 3573 // Resolve.isStatic(env));//DEBUG 3574 3575 // A forward reference is diagnosed if the declaration position 3576 // of the variable is greater than the current tree position 3577 // and the tree and variable definition occur in the same class 3578 // definition. Note that writes don't count as references. 3579 // This check applies only to class and instance 3580 // variables. Local variables follow different scope rules, 3581 // and are subject to definite assignment checking. 3582 if ((env.info.enclVar == v || v.pos > tree.pos) && 3583 v.owner.kind == TYP && 3584 canOwnInitializer(owner(env)) && 3585 v.owner == env.info.scope.owner.enclClass() && 3586 ((v.flags() & STATIC) != 0) == Resolve.isStatic(env) && 3587 (!env.tree.hasTag(ASSIGN) || 3588 TreeInfo.skipParens(((JCAssign) env.tree).lhs) != tree)) { 3589 String suffix = (env.info.enclVar == v) ? 3590 "self.ref" : "forward.ref"; 3591 if (!onlyWarning || isStaticEnumField(v)) { 3592 log.error(tree.pos(), "illegal." + suffix); 3593 } else if (useBeforeDeclarationWarning) { 3594 log.warning(tree.pos(), suffix, v); 3595 } 3596 } 3597 3598 v.getConstValue(); // ensure initializer is evaluated 3599 3600 checkEnumInitializer(tree, env, v); 3601 } 3602 3603 /** 3604 * Check for illegal references to static members of enum. In 3605 * an enum type, constructors and initializers may not 3606 * reference its static members unless they are constant. 3607 * 3608 * @param tree The tree making up the variable reference. 3609 * @param env The current environment. 3610 * @param v The variable's symbol. 3611 * @jls section 8.9 Enums 3612 */ 3613 private void checkEnumInitializer(JCTree tree, Env<AttrContext> env, VarSymbol v) { 3614 // JLS: 3615 // 3616 // "It is a compile-time error to reference a static field 3617 // of an enum type that is not a compile-time constant 3618 // (15.28) from constructors, instance initializer blocks, 3619 // or instance variable initializer expressions of that 3620 // type. It is a compile-time error for the constructors, 3621 // instance initializer blocks, or instance variable 3622 // initializer expressions of an enum constant e to refer 3623 // to itself or to an enum constant of the same type that 3624 // is declared to the right of e." 3625 if (isStaticEnumField(v)) { 3626 ClassSymbol enclClass = env.info.scope.owner.enclClass(); 3627 3628 if (enclClass == null || enclClass.owner == null) 3629 return; 3630 3631 // See if the enclosing class is the enum (or a 3632 // subclass thereof) declaring v. If not, this 3633 // reference is OK. 3634 if (v.owner != enclClass && !types.isSubtype(enclClass.type, v.owner.type)) 3635 return; 3636 3637 // If the reference isn't from an initializer, then 3638 // the reference is OK. 3639 if (!Resolve.isInitializer(env)) 3640 return; 3641 3642 log.error(tree.pos(), "illegal.enum.static.ref"); 3643 } 3644 } 3645 3646 /** Is the given symbol a static, non-constant field of an Enum? 3647 * Note: enum literals should not be regarded as such 3648 */ 3649 private boolean isStaticEnumField(VarSymbol v) { 3650 return Flags.isEnum(v.owner) && 3651 Flags.isStatic(v) && 3652 !Flags.isConstant(v) && 3653 v.name != names._class; 3654 } 3655 3656 /** Can the given symbol be the owner of code which forms part 3657 * if class initialization? This is the case if the symbol is 3658 * a type or field, or if the symbol is the synthetic method. 3659 * owning a block. 3660 */ 3661 private boolean canOwnInitializer(Symbol sym) { 3662 return 3663 (sym.kind & (VAR | TYP)) != 0 || 3664 (sym.kind == MTH && (sym.flags() & BLOCK) != 0); 3665 } 3666 3667 Warner noteWarner = new Warner(); 3668 3669 /** 3670 * Check that method arguments conform to its instantiation. 3671 **/ 3672 public Type checkMethod(Type site, 3673 Symbol sym, 3674 ResultInfo resultInfo, 3675 Env<AttrContext> env, 3676 final List<JCExpression> argtrees, 3677 List<Type> argtypes, 3678 List<Type> typeargtypes) { 3679 // Test (5): if symbol is an instance method of a raw type, issue 3680 // an unchecked warning if its argument types change under erasure. 3681 if (allowGenerics && 3682 (sym.flags() & STATIC) == 0 && 3683 (site.hasTag(CLASS) || site.hasTag(TYPEVAR))) { 3684 Type s = types.asOuterSuper(site, sym.owner); 3685 if (s != null && s.isRaw() && 3686 !types.isSameTypes(sym.type.getParameterTypes(), 3687 sym.erasure(types).getParameterTypes())) { 3688 chk.warnUnchecked(env.tree.pos(), 3689 "unchecked.call.mbr.of.raw.type", 3690 sym, s); 3691 } 3692 } 3693 3694 if (env.info.defaultSuperCallSite != null) { 3695 for (Type sup : types.interfaces(env.enclClass.type).prepend(types.supertype((env.enclClass.type)))) { 3696 if (!sup.tsym.isSubClass(sym.enclClass(), types) || 3697 types.isSameType(sup, env.info.defaultSuperCallSite)) continue; 3698 List<MethodSymbol> icand_sup = 3699 types.interfaceCandidates(sup, (MethodSymbol)sym); 3700 if (icand_sup.nonEmpty() && 3701 icand_sup.head != sym && 3702 icand_sup.head.overrides(sym, icand_sup.head.enclClass(), types, true)) { 3703 log.error(env.tree.pos(), "illegal.default.super.call", env.info.defaultSuperCallSite, 3704 diags.fragment("overridden.default", sym, sup)); 3705 break; 3706 } 3707 } 3708 env.info.defaultSuperCallSite = null; 3709 } 3710 3711 if (sym.isStatic() && site.isInterface() && env.tree.hasTag(APPLY)) { 3712 JCMethodInvocation app = (JCMethodInvocation)env.tree; 3713 if (app.meth.hasTag(SELECT) && 3714 !TreeInfo.isStaticSelector(((JCFieldAccess)app.meth).selected, names)) { 3715 log.error(env.tree.pos(), "illegal.static.intf.meth.call", site); 3716 } 3717 } 3718 3719 // Compute the identifier's instantiated type. 3720 // For methods, we need to compute the instance type by 3721 // Resolve.instantiate from the symbol's type as well as 3722 // any type arguments and value arguments. 3723 noteWarner.clear(); 3724 try { 3725 Type owntype = rs.checkMethod( 3726 env, 3727 site, 3728 sym, 3729 resultInfo, 3730 argtypes, 3731 typeargtypes, 3732 noteWarner); 3733 3734 return chk.checkMethod(owntype, sym, env, argtrees, argtypes, env.info.lastResolveVarargs(), 3735 noteWarner.hasNonSilentLint(LintCategory.UNCHECKED), resultInfo.checkContext.inferenceContext()); 3736 } catch (Infer.InferenceException ex) { 3737 //invalid target type - propagate exception outwards or report error 3738 //depending on the current check context 3739 resultInfo.checkContext.report(env.tree.pos(), ex.getDiagnostic()); 3740 return types.createErrorType(site); 3741 } catch (Resolve.InapplicableMethodException ex) { 3742 Assert.error(ex.getDiagnostic().getMessage(Locale.getDefault())); 3743 return null; 3744 } 3745 } 3746 3747 public void visitLiteral(JCLiteral tree) { 3748 result = check( 3749 tree, litType(tree.typetag).constType(tree.value), VAL, resultInfo); 3750 } 3751 //where 3752 /** Return the type of a literal with given type tag. 3753 */ 3754 Type litType(TypeTag tag) { 3755 return (tag == CLASS) ? syms.stringType : syms.typeOfTag[tag.ordinal()]; 3756 } 3757 3758 public void visitTypeIdent(JCPrimitiveTypeTree tree) { 3759 result = check(tree, syms.typeOfTag[tree.typetag.ordinal()], TYP, resultInfo); 3760 } 3761 3762 public void visitTypeArray(JCArrayTypeTree tree) { 3763 Type etype = attribType(tree.elemtype, env); 3764 Type type = new ArrayType(etype, syms.arrayClass); 3765 result = check(tree, type, TYP, resultInfo); 3766 } 3767 3768 /** Visitor method for parameterized types. 3769 * Bound checking is left until later, since types are attributed 3770 * before supertype structure is completely known 3771 */ 3772 public void visitTypeApply(JCTypeApply tree) { 3773 Type owntype = types.createErrorType(tree.type); 3774 3775 // Attribute functor part of application and make sure it's a class. 3776 Type clazztype = chk.checkClassType(tree.clazz.pos(), attribType(tree.clazz, env)); 3777 3778 // Attribute type parameters 3779 List<Type> actuals = attribTypes(tree.arguments, env); 3780 3781 if (clazztype.hasTag(CLASS)) { 3782 List<Type> formals = clazztype.tsym.type.getTypeArguments(); 3783 if (actuals.isEmpty()) //diamond 3784 actuals = formals; 3785 3786 if (actuals.length() == formals.length()) { 3787 List<Type> a = actuals; 3788 List<Type> f = formals; 3789 while (a.nonEmpty()) { 3790 a.head = a.head.withTypeVar(f.head); 3791 a = a.tail; 3792 f = f.tail; 3793 } 3794 // Compute the proper generic outer 3795 Type clazzOuter = clazztype.getEnclosingType(); 3796 if (clazzOuter.hasTag(CLASS)) { 3797 Type site; 3798 JCExpression clazz = TreeInfo.typeIn(tree.clazz); 3799 if (clazz.hasTag(IDENT)) { 3800 site = env.enclClass.sym.type; 3801 } else if (clazz.hasTag(SELECT)) { 3802 site = ((JCFieldAccess) clazz).selected.type; 3803 } else throw new AssertionError(""+tree); 3804 if (clazzOuter.hasTag(CLASS) && site != clazzOuter) { 3805 if (site.hasTag(CLASS)) 3806 site = types.asOuterSuper(site, clazzOuter.tsym); 3807 if (site == null) 3808 site = types.erasure(clazzOuter); 3809 clazzOuter = site; 3810 } 3811 } 3812 owntype = new ClassType(clazzOuter, actuals, clazztype.tsym); 3813 if (clazztype.isAnnotated()) { 3814 // Use the same AnnotatedType, because it will have 3815 // its annotations set later. 3816 ((AnnotatedType)clazztype).underlyingType = owntype; 3817 owntype = clazztype; 3818 } 3819 } else { 3820 if (formals.length() != 0) { 3821 log.error(tree.pos(), "wrong.number.type.args", 3822 Integer.toString(formals.length())); 3823 } else { 3824 log.error(tree.pos(), "type.doesnt.take.params", clazztype.tsym); 3825 } 3826 owntype = types.createErrorType(tree.type); 3827 } 3828 } 3829 result = check(tree, owntype, TYP, resultInfo); 3830 } 3831 3832 public void visitTypeUnion(JCTypeUnion tree) { 3833 ListBuffer<Type> multicatchTypes = ListBuffer.lb(); 3834 ListBuffer<Type> all_multicatchTypes = null; // lazy, only if needed 3835 for (JCExpression typeTree : tree.alternatives) { 3836 Type ctype = attribType(typeTree, env); 3837 ctype = chk.checkType(typeTree.pos(), 3838 chk.checkClassType(typeTree.pos(), ctype), 3839 syms.throwableType); 3840 if (!ctype.isErroneous()) { 3841 //check that alternatives of a union type are pairwise 3842 //unrelated w.r.t. subtyping 3843 if (chk.intersects(ctype, multicatchTypes.toList())) { 3844 for (Type t : multicatchTypes) { 3845 boolean sub = types.isSubtype(ctype, t); 3846 boolean sup = types.isSubtype(t, ctype); 3847 if (sub || sup) { 3848 //assume 'a' <: 'b' 3849 Type a = sub ? ctype : t; 3850 Type b = sub ? t : ctype; 3851 log.error(typeTree.pos(), "multicatch.types.must.be.disjoint", a, b); 3852 } 3853 } 3854 } 3855 multicatchTypes.append(ctype); 3856 if (all_multicatchTypes != null) 3857 all_multicatchTypes.append(ctype); 3858 } else { 3859 if (all_multicatchTypes == null) { 3860 all_multicatchTypes = ListBuffer.lb(); 3861 all_multicatchTypes.appendList(multicatchTypes); 3862 } 3863 all_multicatchTypes.append(ctype); 3864 } 3865 } 3866 Type t = check(tree, types.lub(multicatchTypes.toList()), TYP, resultInfo); 3867 if (t.hasTag(CLASS)) { 3868 List<Type> alternatives = 3869 ((all_multicatchTypes == null) ? multicatchTypes : all_multicatchTypes).toList(); 3870 t = new UnionClassType((ClassType) t, alternatives); 3871 } 3872 tree.type = result = t; 3873 } 3874 3875 public void visitTypeIntersection(JCTypeIntersection tree) { 3876 attribTypes(tree.bounds, env); 3877 tree.type = result = checkIntersection(tree, tree.bounds); 3878 } 3879 3880 public void visitTypeParameter(JCTypeParameter tree) { 3881 TypeVar typeVar = (TypeVar) tree.type; 3882 3883 if (tree.annotations != null && tree.annotations.nonEmpty()) { 3884 AnnotatedType antype = new AnnotatedType(typeVar); 3885 annotateType(antype, tree.annotations); 3886 tree.type = antype; 3887 } 3888 3889 if (!typeVar.bound.isErroneous()) { 3890 //fixup type-parameter bound computed in 'attribTypeVariables' 3891 typeVar.bound = checkIntersection(tree, tree.bounds); 3892 } 3893 } 3894 3895 Type checkIntersection(JCTree tree, List<JCExpression> bounds) { 3896 Set<Type> boundSet = new HashSet<Type>(); 3897 if (bounds.nonEmpty()) { 3898 // accept class or interface or typevar as first bound. 3899 bounds.head.type = checkBase(bounds.head.type, bounds.head, env, false, false, false); 3900 boundSet.add(types.erasure(bounds.head.type)); 3901 if (bounds.head.type.isErroneous()) { 3902 return bounds.head.type; 3903 } 3904 else if (bounds.head.type.hasTag(TYPEVAR)) { 3905 // if first bound was a typevar, do not accept further bounds. 3906 if (bounds.tail.nonEmpty()) { 3907 log.error(bounds.tail.head.pos(), 3908 "type.var.may.not.be.followed.by.other.bounds"); 3909 return bounds.head.type; 3910 } 3911 } else { 3912 // if first bound was a class or interface, accept only interfaces 3913 // as further bounds. 3914 for (JCExpression bound : bounds.tail) { 3915 bound.type = checkBase(bound.type, bound, env, false, true, false); 3916 if (bound.type.isErroneous()) { 3917 bounds = List.of(bound); 3918 } 3919 else if (bound.type.hasTag(CLASS)) { 3920 chk.checkNotRepeated(bound.pos(), types.erasure(bound.type), boundSet); 3921 } 3922 } 3923 } 3924 } 3925 3926 if (bounds.length() == 0) { 3927 return syms.objectType; 3928 } else if (bounds.length() == 1) { 3929 return bounds.head.type; 3930 } else { 3931 Type owntype = types.makeCompoundType(TreeInfo.types(bounds)); 3932 if (tree.hasTag(TYPEINTERSECTION)) { 3933 ((IntersectionClassType)owntype).intersectionKind = 3934 IntersectionClassType.IntersectionKind.EXPLICIT; 3935 } 3936 // ... the variable's bound is a class type flagged COMPOUND 3937 // (see comment for TypeVar.bound). 3938 // In this case, generate a class tree that represents the 3939 // bound class, ... 3940 JCExpression extending; 3941 List<JCExpression> implementing; 3942 if (!bounds.head.type.isInterface()) { 3943 extending = bounds.head; 3944 implementing = bounds.tail; 3945 } else { 3946 extending = null; 3947 implementing = bounds; 3948 } 3949 JCClassDecl cd = make.at(tree).ClassDef( 3950 make.Modifiers(PUBLIC | ABSTRACT), 3951 names.empty, List.<JCTypeParameter>nil(), 3952 extending, implementing, List.<JCTree>nil()); 3953 3954 ClassSymbol c = (ClassSymbol)owntype.tsym; 3955 Assert.check((c.flags() & COMPOUND) != 0); 3956 cd.sym = c; 3957 c.sourcefile = env.toplevel.sourcefile; 3958 3959 // ... and attribute the bound class 3960 c.flags_field |= UNATTRIBUTED; 3961 Env<AttrContext> cenv = enter.classEnv(cd, env); 3962 enter.typeEnvs.put(c, cenv); 3963 attribClass(c); 3964 return owntype; 3965 } 3966 } 3967 3968 public void visitWildcard(JCWildcard tree) { 3969 //- System.err.println("visitWildcard("+tree+");");//DEBUG 3970 Type type = (tree.kind.kind == BoundKind.UNBOUND) 3971 ? syms.objectType 3972 : attribType(tree.inner, env); 3973 result = check(tree, new WildcardType(chk.checkRefType(tree.pos(), type), 3974 tree.kind.kind, 3975 syms.boundClass), 3976 TYP, resultInfo); 3977 } 3978 3979 public void visitAnnotation(JCAnnotation tree) { 3980 log.error(tree.pos(), "annotation.not.valid.for.type", pt()); 3981 result = tree.type = syms.errType; 3982 } 3983 3984 public void visitAnnotatedType(JCAnnotatedType tree) { 3985 Type underlyingType = attribType(tree.getUnderlyingType(), env); 3986 this.attribAnnotationTypes(tree.annotations, env); 3987 AnnotatedType antype = new AnnotatedType(underlyingType); 3988 annotateType(antype, tree.annotations); 3989 result = tree.type = antype; 3990 } 3991 3992 /** 3993 * Apply the annotations to the particular type. 3994 */ 3995 public void annotateType(final AnnotatedType type, final List<JCAnnotation> annotations) { 3996 if (annotations.isEmpty()) 3997 return; 3998 annotate.typeAnnotation(new Annotate.Annotator() { 3999 @Override 4000 public String toString() { 4001 return "annotate " + annotations + " onto " + type; 4002 } 4003 @Override 4004 public void enterAnnotation() { 4005 List<Attribute.TypeCompound> compounds = fromAnnotations(annotations); 4006 type.typeAnnotations = compounds; 4007 } 4008 }); 4009 } 4010 4011 private static List<Attribute.TypeCompound> fromAnnotations(List<JCAnnotation> annotations) { 4012 if (annotations.isEmpty()) 4013 return List.nil(); 4014 4015 ListBuffer<Attribute.TypeCompound> buf = ListBuffer.lb(); 4016 for (JCAnnotation anno : annotations) { 4017 if (anno.attribute != null) { 4018 // TODO: this null-check is only needed for an obscure 4019 // ordering issue, where annotate.flush is called when 4020 // the attribute is not set yet. For an example failure 4021 // try the referenceinfos/NestedTypes.java test. 4022 // Any better solutions? 4023 buf.append((Attribute.TypeCompound) anno.attribute); 4024 } 4025 } 4026 return buf.toList(); 4027 } 4028 4029 public void visitErroneous(JCErroneous tree) { 4030 if (tree.errs != null) 4031 for (JCTree err : tree.errs) 4032 attribTree(err, env, new ResultInfo(ERR, pt())); 4033 result = tree.type = syms.errType; 4034 } 4035 4036 /** Default visitor method for all other trees. 4037 */ 4038 public void visitTree(JCTree tree) { 4039 throw new AssertionError(); 4040 } 4041 4042 /** 4043 * Attribute an env for either a top level tree or class declaration. 4044 */ 4045 public void attrib(Env<AttrContext> env) { 4046 if (env.tree.hasTag(TOPLEVEL)) 4047 attribTopLevel(env); 4048 else 4049 attribClass(env.tree.pos(), env.enclClass.sym); 4050 } 4051 4052 /** 4053 * Attribute a top level tree. These trees are encountered when the 4054 * package declaration has annotations. 4055 */ 4056 public void attribTopLevel(Env<AttrContext> env) { 4057 JCCompilationUnit toplevel = env.toplevel; 4058 try { 4059 annotate.flush(); 4060 chk.validateAnnotations(toplevel.packageAnnotations, toplevel.packge); 4061 } catch (CompletionFailure ex) { 4062 chk.completionError(toplevel.pos(), ex); 4063 } 4064 } 4065 4066 /** Main method: attribute class definition associated with given class symbol. 4067 * reporting completion failures at the given position. 4068 * @param pos The source position at which completion errors are to be 4069 * reported. 4070 * @param c The class symbol whose definition will be attributed. 4071 */ 4072 public void attribClass(DiagnosticPosition pos, ClassSymbol c) { 4073 try { 4074 annotate.flush(); 4075 attribClass(c); 4076 } catch (CompletionFailure ex) { 4077 chk.completionError(pos, ex); 4078 } 4079 } 4080 4081 /** Attribute class definition associated with given class symbol. 4082 * @param c The class symbol whose definition will be attributed. 4083 */ 4084 void attribClass(ClassSymbol c) throws CompletionFailure { 4085 if (c.type.hasTag(ERROR)) return; 4086 4087 // Check for cycles in the inheritance graph, which can arise from 4088 // ill-formed class files. 4089 chk.checkNonCyclic(null, c.type); 4090 4091 Type st = types.supertype(c.type); 4092 if ((c.flags_field & Flags.COMPOUND) == 0) { 4093 // First, attribute superclass. 4094 if (st.hasTag(CLASS)) 4095 attribClass((ClassSymbol)st.tsym); 4096 4097 // Next attribute owner, if it is a class. 4098 if (c.owner.kind == TYP && c.owner.type.hasTag(CLASS)) 4099 attribClass((ClassSymbol)c.owner); 4100 } 4101 4102 // The previous operations might have attributed the current class 4103 // if there was a cycle. So we test first whether the class is still 4104 // UNATTRIBUTED. 4105 if ((c.flags_field & UNATTRIBUTED) != 0) { 4106 c.flags_field &= ~UNATTRIBUTED; 4107 4108 // Get environment current at the point of class definition. 4109 Env<AttrContext> env = enter.typeEnvs.get(c); 4110 4111 // The info.lint field in the envs stored in enter.typeEnvs is deliberately uninitialized, 4112 // because the annotations were not available at the time the env was created. Therefore, 4113 // we look up the environment chain for the first enclosing environment for which the 4114 // lint value is set. Typically, this is the parent env, but might be further if there 4115 // are any envs created as a result of TypeParameter nodes. 4116 Env<AttrContext> lintEnv = env; 4117 while (lintEnv.info.lint == null) 4118 lintEnv = lintEnv.next; 4119 4120 // Having found the enclosing lint value, we can initialize the lint value for this class 4121 env.info.lint = lintEnv.info.lint.augment(c.annotations, c.flags()); 4122 4123 Lint prevLint = chk.setLint(env.info.lint); 4124 JavaFileObject prev = log.useSource(c.sourcefile); 4125 ResultInfo prevReturnRes = env.info.returnResult; 4126 4127 try { 4128 env.info.returnResult = null; 4129 // java.lang.Enum may not be subclassed by a non-enum 4130 if (st.tsym == syms.enumSym && 4131 ((c.flags_field & (Flags.ENUM|Flags.COMPOUND)) == 0)) 4132 log.error(env.tree.pos(), "enum.no.subclassing"); 4133 4134 // Enums may not be extended by source-level classes 4135 if (st.tsym != null && 4136 ((st.tsym.flags_field & Flags.ENUM) != 0) && 4137 ((c.flags_field & (Flags.ENUM | Flags.COMPOUND)) == 0)) { 4138 log.error(env.tree.pos(), "enum.types.not.extensible"); 4139 } 4140 attribClassBody(env, c); 4141 4142 chk.checkDeprecatedAnnotation(env.tree.pos(), c); 4143 chk.checkClassOverrideEqualsAndHashIfNeeded(env.tree.pos(), c); 4144 } finally { 4145 env.info.returnResult = prevReturnRes; 4146 log.useSource(prev); 4147 chk.setLint(prevLint); 4148 } 4149 4150 } 4151 } 4152 4153 public void visitImport(JCImport tree) { 4154 // nothing to do 4155 } 4156 4157 /** Finish the attribution of a class. */ 4158 private void attribClassBody(Env<AttrContext> env, ClassSymbol c) { 4159 JCClassDecl tree = (JCClassDecl)env.tree; 4160 Assert.check(c == tree.sym); 4161 4162 // Validate annotations 4163 chk.validateAnnotations(tree.mods.annotations, c); 4164 4165 // Validate type parameters, supertype and interfaces. 4166 attribStats(tree.typarams, env); 4167 if (!c.isAnonymous()) { 4168 //already checked if anonymous 4169 chk.validate(tree.typarams, env); 4170 chk.validate(tree.extending, env); 4171 chk.validate(tree.implementing, env); 4172 } 4173 4174 // If this is a non-abstract class, check that it has no abstract 4175 // methods or unimplemented methods of an implemented interface. 4176 if ((c.flags() & (ABSTRACT | INTERFACE)) == 0) { 4177 if (!relax) 4178 chk.checkAllDefined(tree.pos(), c); 4179 } 4180 4181 if ((c.flags() & ANNOTATION) != 0) { 4182 if (tree.implementing.nonEmpty()) 4183 log.error(tree.implementing.head.pos(), 4184 "cant.extend.intf.annotation"); 4185 if (tree.typarams.nonEmpty()) 4186 log.error(tree.typarams.head.pos(), 4187 "intf.annotation.cant.have.type.params"); 4188 4189 // If this annotation has a @Repeatable, validate 4190 Attribute.Compound repeatable = c.attribute(syms.repeatableType.tsym); 4191 if (repeatable != null) { 4192 // get diagnostic position for error reporting 4193 DiagnosticPosition cbPos = getDiagnosticPosition(tree, repeatable.type); 4194 Assert.checkNonNull(cbPos); 4195 4196 chk.validateRepeatable(c, repeatable, cbPos); 4197 } 4198 } else { 4199 // Check that all extended classes and interfaces 4200 // are compatible (i.e. no two define methods with same arguments 4201 // yet different return types). (JLS 8.4.6.3) 4202 chk.checkCompatibleSupertypes(tree.pos(), c.type); 4203 if (allowDefaultMethods) { 4204 chk.checkDefaultMethodClashes(tree.pos(), c.type); 4205 } 4206 } 4207 4208 // Check that class does not import the same parameterized interface 4209 // with two different argument lists. 4210 chk.checkClassBounds(tree.pos(), c.type); 4211 4212 tree.type = c.type; 4213 4214 for (List<JCTypeParameter> l = tree.typarams; 4215 l.nonEmpty(); l = l.tail) { 4216 Assert.checkNonNull(env.info.scope.lookup(l.head.name).scope); 4217 } 4218 4219 // Check that a generic class doesn't extend Throwable 4220 if (!c.type.allparams().isEmpty() && types.isSubtype(c.type, syms.throwableType)) 4221 log.error(tree.extending.pos(), "generic.throwable"); 4222 4223 // Check that all methods which implement some 4224 // method conform to the method they implement. 4225 chk.checkImplementations(tree); 4226 4227 //check that a resource implementing AutoCloseable cannot throw InterruptedException 4228 checkAutoCloseable(tree.pos(), env, c.type); 4229 4230 for (List<JCTree> l = tree.defs; l.nonEmpty(); l = l.tail) { 4231 // Attribute declaration 4232 attribStat(l.head, env); 4233 // Check that declarations in inner classes are not static (JLS 8.1.2) 4234 // Make an exception for static constants. 4235 if (c.owner.kind != PCK && 4236 ((c.flags() & STATIC) == 0 || c.name == names.empty) && 4237 (TreeInfo.flags(l.head) & (STATIC | INTERFACE)) != 0) { 4238 Symbol sym = null; 4239 if (l.head.hasTag(VARDEF)) sym = ((JCVariableDecl) l.head).sym; 4240 if (sym == null || 4241 sym.kind != VAR || 4242 ((VarSymbol) sym).getConstValue() == null) 4243 log.error(l.head.pos(), "icls.cant.have.static.decl", c); 4244 } 4245 } 4246 4247 // Check for cycles among non-initial constructors. 4248 chk.checkCyclicConstructors(tree); 4249 4250 // Check for cycles among annotation elements. 4251 chk.checkNonCyclicElements(tree); 4252 4253 // Check for proper use of serialVersionUID 4254 if (env.info.lint.isEnabled(LintCategory.SERIAL) && 4255 isSerializable(c) && 4256 (c.flags() & Flags.ENUM) == 0 && 4257 (c.flags() & ABSTRACT) == 0) { 4258 checkSerialVersionUID(tree, c); 4259 } 4260 4261 // Correctly organize the postions of the type annotations 4262 TypeAnnotations.organizeTypeAnnotationsBodies(this.syms, this.names, this.log, tree); 4263 4264 // Check type annotations applicability rules 4265 validateTypeAnnotations(tree); 4266 } 4267 // where 4268 /** get a diagnostic position for an attribute of Type t, or null if attribute missing */ 4269 private DiagnosticPosition getDiagnosticPosition(JCClassDecl tree, Type t) { 4270 for(List<JCAnnotation> al = tree.mods.annotations; !al.isEmpty(); al = al.tail) { 4271 if (types.isSameType(al.head.annotationType.type, t)) 4272 return al.head.pos(); 4273 } 4274 4275 return null; 4276 } 4277 4278 /** check if a class is a subtype of Serializable, if that is available. */ 4279 private boolean isSerializable(ClassSymbol c) { 4280 try { 4281 syms.serializableType.complete(); 4282 } 4283 catch (CompletionFailure e) { 4284 return false; 4285 } 4286 return types.isSubtype(c.type, syms.serializableType); 4287 } 4288 4289 /** Check that an appropriate serialVersionUID member is defined. */ 4290 private void checkSerialVersionUID(JCClassDecl tree, ClassSymbol c) { 4291 4292 // check for presence of serialVersionUID 4293 Scope.Entry e = c.members().lookup(names.serialVersionUID); 4294 while (e.scope != null && e.sym.kind != VAR) e = e.next(); 4295 if (e.scope == null) { 4296 log.warning(LintCategory.SERIAL, 4297 tree.pos(), "missing.SVUID", c); 4298 return; 4299 } 4300 4301 // check that it is static final 4302 VarSymbol svuid = (VarSymbol)e.sym; 4303 if ((svuid.flags() & (STATIC | FINAL)) != 4304 (STATIC | FINAL)) 4305 log.warning(LintCategory.SERIAL, 4306 TreeInfo.diagnosticPositionFor(svuid, tree), "improper.SVUID", c); 4307 4308 // check that it is long 4309 else if (!svuid.type.hasTag(LONG)) 4310 log.warning(LintCategory.SERIAL, 4311 TreeInfo.diagnosticPositionFor(svuid, tree), "long.SVUID", c); 4312 4313 // check constant 4314 else if (svuid.getConstValue() == null) 4315 log.warning(LintCategory.SERIAL, 4316 TreeInfo.diagnosticPositionFor(svuid, tree), "constant.SVUID", c); 4317 } 4318 4319 private Type capture(Type type) { 4320 //do not capture free types 4321 return resultInfo.checkContext.inferenceContext().free(type) ? 4322 type : types.capture(type); 4323 } 4324 4325 private void validateTypeAnnotations(JCTree tree) { 4326 tree.accept(typeAnnotationsValidator); 4327 } 4328 //where 4329 private final JCTree.Visitor typeAnnotationsValidator = new TreeScanner() { 4330 4331 private boolean checkAllAnnotations = false; 4332 4333 public void visitAnnotation(JCAnnotation tree) { 4334 if (tree.hasTag(TYPE_ANNOTATION) || checkAllAnnotations) { 4335 chk.validateTypeAnnotation(tree, false); 4336 } 4337 super.visitAnnotation(tree); 4338 } 4339 public void visitTypeParameter(JCTypeParameter tree) { 4340 chk.validateTypeAnnotations(tree.annotations, true); 4341 scan(tree.bounds); 4342 // Don't call super. 4343 // This is needed because above we call validateTypeAnnotation with 4344 // false, which would forbid annotations on type parameters. 4345 // super.visitTypeParameter(tree); 4346 } 4347 public void visitMethodDef(JCMethodDecl tree) { 4348 if (tree.recvparam != null && 4349 tree.recvparam.vartype.type.getKind() != TypeKind.ERROR) { 4350 checkForDeclarationAnnotations(tree.recvparam.mods.annotations, 4351 tree.recvparam.vartype.type.tsym); 4352 } 4353 if (tree.restype != null && tree.restype.type != null) { 4354 validateAnnotatedType(tree.restype, tree.restype.type); 4355 } 4356 super.visitMethodDef(tree); 4357 } 4358 public void visitVarDef(final JCVariableDecl tree) { 4359 if (tree.sym != null && tree.sym.type != null) 4360 validateAnnotatedType(tree, tree.sym.type); 4361 super.visitVarDef(tree); 4362 } 4363 public void visitTypeCast(JCTypeCast tree) { 4364 if (tree.clazz != null && tree.clazz.type != null) 4365 validateAnnotatedType(tree.clazz, tree.clazz.type); 4366 super.visitTypeCast(tree); 4367 } 4368 public void visitTypeTest(JCInstanceOf tree) { 4369 if (tree.clazz != null && tree.clazz.type != null) 4370 validateAnnotatedType(tree.clazz, tree.clazz.type); 4371 super.visitTypeTest(tree); 4372 } 4373 public void visitNewClass(JCNewClass tree) { 4374 if (tree.clazz.hasTag(ANNOTATED_TYPE)) { 4375 boolean prevCheck = this.checkAllAnnotations; 4376 try { 4377 this.checkAllAnnotations = true; 4378 scan(((JCAnnotatedType)tree.clazz).annotations); 4379 } finally { 4380 this.checkAllAnnotations = prevCheck; 4381 } 4382 } 4383 super.visitNewClass(tree); 4384 } 4385 public void visitNewArray(JCNewArray tree) { 4386 if (tree.elemtype != null && tree.elemtype.hasTag(ANNOTATED_TYPE)) { 4387 boolean prevCheck = this.checkAllAnnotations; 4388 try { 4389 this.checkAllAnnotations = true; 4390 scan(((JCAnnotatedType)tree.elemtype).annotations); 4391 } finally { 4392 this.checkAllAnnotations = prevCheck; 4393 } 4394 } 4395 super.visitNewArray(tree); 4396 } 4397 4398 /* I would want to model this after 4399 * com.sun.tools.javac.comp.Check.Validator.visitSelectInternal(JCFieldAccess) 4400 * and override visitSelect and visitTypeApply. 4401 * However, we only set the annotated type in the top-level type 4402 * of the symbol. 4403 * Therefore, we need to override each individual location where a type 4404 * can occur. 4405 */ 4406 private void validateAnnotatedType(final JCTree errtree, final Type type) { 4407 if (type.getEnclosingType() != null && 4408 type != type.getEnclosingType()) { 4409 validateEnclosingAnnotatedType(errtree, type.getEnclosingType()); 4410 } 4411 for (Type targ : type.getTypeArguments()) { 4412 validateAnnotatedType(errtree, targ); 4413 } 4414 } 4415 private void validateEnclosingAnnotatedType(final JCTree errtree, final Type type) { 4416 validateAnnotatedType(errtree, type); 4417 if (type.tsym != null && 4418 type.tsym.isStatic() && 4419 type.getAnnotationMirrors().nonEmpty()) { 4420 // Enclosing static classes cannot have type annotations. 4421 log.error(errtree.pos(), "cant.annotate.static.class"); 4422 } 4423 } 4424 }; 4425 4426 // <editor-fold desc="post-attribution visitor"> 4427 4428 /** 4429 * Handle missing types/symbols in an AST. This routine is useful when 4430 * the compiler has encountered some errors (which might have ended up 4431 * terminating attribution abruptly); if the compiler is used in fail-over 4432 * mode (e.g. by an IDE) and the AST contains semantic errors, this routine 4433 * prevents NPE to be progagated during subsequent compilation steps. 4434 */ 4435 public void postAttr(JCTree tree) { 4436 new PostAttrAnalyzer().scan(tree); 4437 } 4438 4439 class PostAttrAnalyzer extends TreeScanner { 4440 4441 private void initTypeIfNeeded(JCTree that) { 4442 if (that.type == null) { 4443 that.type = syms.unknownType; 4444 } 4445 } 4446 4447 @Override 4448 public void scan(JCTree tree) { 4449 if (tree == null) return; 4450 if (tree instanceof JCExpression) { 4451 initTypeIfNeeded(tree); 4452 } 4453 super.scan(tree); 4454 } 4455 4456 @Override 4457 public void visitIdent(JCIdent that) { 4458 if (that.sym == null) { 4459 that.sym = syms.unknownSymbol; 4460 } 4461 } 4462 4463 @Override 4464 public void visitSelect(JCFieldAccess that) { 4465 if (that.sym == null) { 4466 that.sym = syms.unknownSymbol; 4467 } 4468 super.visitSelect(that); 4469 } 4470 4471 @Override 4472 public void visitClassDef(JCClassDecl that) { 4473 initTypeIfNeeded(that); 4474 if (that.sym == null) { 4475 that.sym = new ClassSymbol(0, that.name, that.type, syms.noSymbol); 4476 } 4477 super.visitClassDef(that); 4478 } 4479 4480 @Override 4481 public void visitMethodDef(JCMethodDecl that) { 4482 initTypeIfNeeded(that); 4483 if (that.sym == null) { 4484 that.sym = new MethodSymbol(0, that.name, that.type, syms.noSymbol); 4485 } 4486 super.visitMethodDef(that); 4487 } 4488 4489 @Override 4490 public void visitVarDef(JCVariableDecl that) { 4491 initTypeIfNeeded(that); 4492 if (that.sym == null) { 4493 that.sym = new VarSymbol(0, that.name, that.type, syms.noSymbol); 4494 that.sym.adr = 0; 4495 } 4496 super.visitVarDef(that); 4497 } 4498 4499 @Override 4500 public void visitNewClass(JCNewClass that) { 4501 if (that.constructor == null) { 4502 that.constructor = new MethodSymbol(0, names.init, syms.unknownType, syms.noSymbol); 4503 } 4504 if (that.constructorType == null) { 4505 that.constructorType = syms.unknownType; 4506 } 4507 super.visitNewClass(that); 4508 } 4509 4510 @Override 4511 public void visitAssignop(JCAssignOp that) { 4512 if (that.operator == null) 4513 that.operator = new OperatorSymbol(names.empty, syms.unknownType, -1, syms.noSymbol); 4514 super.visitAssignop(that); 4515 } 4516 4517 @Override 4518 public void visitBinary(JCBinary that) { 4519 if (that.operator == null) 4520 that.operator = new OperatorSymbol(names.empty, syms.unknownType, -1, syms.noSymbol); 4521 super.visitBinary(that); 4522 } 4523 4524 @Override 4525 public void visitUnary(JCUnary that) { 4526 if (that.operator == null) 4527 that.operator = new OperatorSymbol(names.empty, syms.unknownType, -1, syms.noSymbol); 4528 super.visitUnary(that); 4529 } 4530 4531 @Override 4532 public void visitLambda(JCLambda that) { 4533 super.visitLambda(that); 4534 if (that.descriptorType == null) { 4535 that.descriptorType = syms.unknownType; 4536 } 4537 if (that.targets == null) { 4538 that.targets = List.nil(); 4539 } 4540 } 4541 4542 @Override 4543 public void visitReference(JCMemberReference that) { 4544 super.visitReference(that); 4545 if (that.sym == null) { 4546 that.sym = new MethodSymbol(0, names.empty, syms.unknownType, syms.noSymbol); 4547 } 4548 if (that.descriptorType == null) { 4549 that.descriptorType = syms.unknownType; 4550 } 4551 if (that.targets == null) { 4552 that.targets = List.nil(); 4553 } 4554 } 4555 } 4556 // </editor-fold> 4557 }