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.annotationsPendingCompletion()) { 761 env.info.lint = lintEnv.info.lint; 762 } else { 763 env.info.lint = lintEnv.info.lint.augment(env.info.enclVar); 764 } 765 766 Lint prevLint = chk.setLint(env.info.lint); 767 JavaFileObject prevSource = log.useSource(env.toplevel.sourcefile); 768 769 try { 770 // Use null as symbol to not attach the type annotation to any symbol. 771 // The initializer will later also be visited and then we'll attach 772 // to the symbol. 773 // This prevents having multiple type annotations, just because of 774 // lazy constant value evaluation. 775 memberEnter.typeAnnotate(initializer, env, null); 776 annotate.flush(); 777 Type itype = attribExpr(initializer, env, type); 778 if (itype.constValue() != null) 779 return coerce(itype, type).constValue(); 780 else 781 return null; 782 } finally { 783 env.info.lint = prevLint; 784 log.useSource(prevSource); 785 } 786 } 787 788 /** Attribute type reference in an `extends' or `implements' clause. 789 * Supertypes of anonymous inner classes are usually already attributed. 790 * 791 * @param tree The tree making up the type reference. 792 * @param env The environment current at the reference. 793 * @param classExpected true if only a class is expected here. 794 * @param interfaceExpected true if only an interface is expected here. 795 */ 796 Type attribBase(JCTree tree, 797 Env<AttrContext> env, 798 boolean classExpected, 799 boolean interfaceExpected, 800 boolean checkExtensible) { 801 Type t = tree.type != null ? 802 tree.type : 803 attribType(tree, env); 804 return checkBase(t, tree, env, classExpected, interfaceExpected, checkExtensible); 805 } 806 Type checkBase(Type t, 807 JCTree tree, 808 Env<AttrContext> env, 809 boolean classExpected, 810 boolean interfaceExpected, 811 boolean checkExtensible) { 812 if (t.isErroneous()) 813 return t; 814 if (t.hasTag(TYPEVAR) && !classExpected && !interfaceExpected) { 815 // check that type variable is already visible 816 if (t.getUpperBound() == null) { 817 log.error(tree.pos(), "illegal.forward.ref"); 818 return types.createErrorType(t); 819 } 820 } else { 821 t = chk.checkClassType(tree.pos(), t, checkExtensible|!allowGenerics); 822 } 823 if (interfaceExpected && (t.tsym.flags() & INTERFACE) == 0) { 824 log.error(tree.pos(), "intf.expected.here"); 825 // return errType is necessary since otherwise there might 826 // be undetected cycles which cause attribution to loop 827 return types.createErrorType(t); 828 } else if (checkExtensible && 829 classExpected && 830 (t.tsym.flags() & INTERFACE) != 0) { 831 log.error(tree.pos(), "no.intf.expected.here"); 832 return types.createErrorType(t); 833 } 834 if (checkExtensible && 835 ((t.tsym.flags() & FINAL) != 0)) { 836 log.error(tree.pos(), 837 "cant.inherit.from.final", t.tsym); 838 } 839 chk.checkNonCyclic(tree.pos(), t); 840 return t; 841 } 842 843 Type attribIdentAsEnumType(Env<AttrContext> env, JCIdent id) { 844 Assert.check((env.enclClass.sym.flags() & ENUM) != 0); 845 id.type = env.info.scope.owner.type; 846 id.sym = env.info.scope.owner; 847 return id.type; 848 } 849 850 public void visitClassDef(JCClassDecl tree) { 851 // Local classes have not been entered yet, so we need to do it now: 852 if ((env.info.scope.owner.kind & (VAR | MTH)) != 0) 853 enter.classEnter(tree, env); 854 855 ClassSymbol c = tree.sym; 856 if (c == null) { 857 // exit in case something drastic went wrong during enter. 858 result = null; 859 } else { 860 // make sure class has been completed: 861 c.complete(); 862 863 // If this class appears as an anonymous class 864 // in a superclass constructor call where 865 // no explicit outer instance is given, 866 // disable implicit outer instance from being passed. 867 // (This would be an illegal access to "this before super"). 868 if (env.info.isSelfCall && 869 env.tree.hasTag(NEWCLASS) && 870 ((JCNewClass) env.tree).encl == null) 871 { 872 c.flags_field |= NOOUTERTHIS; 873 } 874 attribClass(tree.pos(), c); 875 result = tree.type = c.type; 876 } 877 } 878 879 public void visitMethodDef(JCMethodDecl tree) { 880 MethodSymbol m = tree.sym; 881 boolean isDefaultMethod = (m.flags() & DEFAULT) != 0; 882 883 Lint lint = env.info.lint.augment(m); 884 Lint prevLint = chk.setLint(lint); 885 MethodSymbol prevMethod = chk.setMethod(m); 886 try { 887 deferredLintHandler.flush(tree.pos()); 888 chk.checkDeprecatedAnnotation(tree.pos(), m); 889 890 891 // Create a new environment with local scope 892 // for attributing the method. 893 Env<AttrContext> localEnv = memberEnter.methodEnv(tree, env); 894 localEnv.info.lint = lint; 895 896 attribStats(tree.typarams, localEnv); 897 898 // If we override any other methods, check that we do so properly. 899 // JLS ??? 900 if (m.isStatic()) { 901 chk.checkHideClashes(tree.pos(), env.enclClass.type, m); 902 } else { 903 chk.checkOverrideClashes(tree.pos(), env.enclClass.type, m); 904 } 905 chk.checkOverride(tree, m); 906 907 if (isDefaultMethod && types.overridesObjectMethod(m.enclClass(), m)) { 908 log.error(tree, "default.overrides.object.member", m.name, Kinds.kindName(m.location()), m.location()); 909 } 910 911 // Enter all type parameters into the local method scope. 912 for (List<JCTypeParameter> l = tree.typarams; l.nonEmpty(); l = l.tail) 913 localEnv.info.scope.enterIfAbsent(l.head.type.tsym); 914 915 ClassSymbol owner = env.enclClass.sym; 916 if ((owner.flags() & ANNOTATION) != 0 && 917 tree.params.nonEmpty()) 918 log.error(tree.params.head.pos(), 919 "intf.annotation.members.cant.have.params"); 920 921 // Attribute all value parameters. 922 for (List<JCVariableDecl> l = tree.params; l.nonEmpty(); l = l.tail) { 923 attribStat(l.head, localEnv); 924 } 925 926 chk.checkVarargsMethodDecl(localEnv, tree); 927 928 // Check that type parameters are well-formed. 929 chk.validate(tree.typarams, localEnv); 930 931 // Check that result type is well-formed. 932 chk.validate(tree.restype, localEnv); 933 934 // Check that receiver type is well-formed. 935 if (tree.recvparam != null) { 936 // Use a new environment to check the receiver parameter. 937 // Otherwise I get "might not have been initialized" errors. 938 // Is there a better way? 939 Env<AttrContext> newEnv = memberEnter.methodEnv(tree, env); 940 attribType(tree.recvparam, newEnv); 941 chk.validate(tree.recvparam, newEnv); 942 } 943 944 // annotation method checks 945 if ((owner.flags() & ANNOTATION) != 0) { 946 // annotation method cannot have throws clause 947 if (tree.thrown.nonEmpty()) { 948 log.error(tree.thrown.head.pos(), 949 "throws.not.allowed.in.intf.annotation"); 950 } 951 // annotation method cannot declare type-parameters 952 if (tree.typarams.nonEmpty()) { 953 log.error(tree.typarams.head.pos(), 954 "intf.annotation.members.cant.have.type.params"); 955 } 956 // validate annotation method's return type (could be an annotation type) 957 chk.validateAnnotationType(tree.restype); 958 // ensure that annotation method does not clash with members of Object/Annotation 959 chk.validateAnnotationMethod(tree.pos(), m); 960 961 if (tree.defaultValue != null) { 962 // if default value is an annotation, check it is a well-formed 963 // annotation value (e.g. no duplicate values, no missing values, etc.) 964 chk.validateAnnotationTree(tree.defaultValue); 965 } 966 } 967 968 for (List<JCExpression> l = tree.thrown; l.nonEmpty(); l = l.tail) 969 chk.checkType(l.head.pos(), l.head.type, syms.throwableType); 970 971 if (tree.body == null) { 972 // Empty bodies are only allowed for 973 // abstract, native, or interface methods, or for methods 974 // in a retrofit signature class. 975 if (isDefaultMethod || (tree.sym.flags() & (ABSTRACT | NATIVE)) == 0 && 976 !relax) 977 log.error(tree.pos(), "missing.meth.body.or.decl.abstract"); 978 if (tree.defaultValue != null) { 979 if ((owner.flags() & ANNOTATION) == 0) 980 log.error(tree.pos(), 981 "default.allowed.in.intf.annotation.member"); 982 } 983 } else if ((tree.sym.flags() & ABSTRACT) != 0 && !isDefaultMethod) { 984 if ((owner.flags() & INTERFACE) != 0) { 985 log.error(tree.body.pos(), "intf.meth.cant.have.body"); 986 } else { 987 log.error(tree.pos(), "abstract.meth.cant.have.body"); 988 } 989 } else if ((tree.mods.flags & NATIVE) != 0) { 990 log.error(tree.pos(), "native.meth.cant.have.body"); 991 } else { 992 // Add an implicit super() call unless an explicit call to 993 // super(...) or this(...) is given 994 // or we are compiling class java.lang.Object. 995 if (tree.name == names.init && owner.type != syms.objectType) { 996 JCBlock body = tree.body; 997 if (body.stats.isEmpty() || 998 !TreeInfo.isSelfCall(body.stats.head)) { 999 body.stats = body.stats. 1000 prepend(memberEnter.SuperCall(make.at(body.pos), 1001 List.<Type>nil(), 1002 List.<JCVariableDecl>nil(), 1003 false)); 1004 } else if ((env.enclClass.sym.flags() & ENUM) != 0 && 1005 (tree.mods.flags & GENERATEDCONSTR) == 0 && 1006 TreeInfo.isSuperCall(body.stats.head)) { 1007 // enum constructors are not allowed to call super 1008 // directly, so make sure there aren't any super calls 1009 // in enum constructors, except in the compiler 1010 // generated one. 1011 log.error(tree.body.stats.head.pos(), 1012 "call.to.super.not.allowed.in.enum.ctor", 1013 env.enclClass.sym); 1014 } 1015 } 1016 1017 // Attribute all type annotations in the body 1018 memberEnter.typeAnnotate(tree.body, localEnv, m); 1019 annotate.flush(); 1020 1021 // Attribute method body. 1022 attribStat(tree.body, localEnv); 1023 } 1024 1025 localEnv.info.scope.leave(); 1026 result = tree.type = m.type; 1027 chk.validateAnnotations(tree.mods.annotations, m); 1028 } 1029 finally { 1030 chk.setLint(prevLint); 1031 chk.setMethod(prevMethod); 1032 } 1033 } 1034 1035 public void visitVarDef(JCVariableDecl tree) { 1036 // Local variables have not been entered yet, so we need to do it now: 1037 if (env.info.scope.owner.kind == MTH) { 1038 if (tree.sym != null) { 1039 // parameters have already been entered 1040 env.info.scope.enter(tree.sym); 1041 } else { 1042 memberEnter.memberEnter(tree, env); 1043 annotate.flush(); 1044 } 1045 } else { 1046 if (tree.init != null) { 1047 // Field initializer expression need to be entered. 1048 memberEnter.typeAnnotate(tree.init, env, tree.sym); 1049 annotate.flush(); 1050 } 1051 } 1052 1053 VarSymbol v = tree.sym; 1054 Lint lint = env.info.lint.augment(v); 1055 Lint prevLint = chk.setLint(lint); 1056 1057 // Check that the variable's declared type is well-formed. 1058 boolean isImplicitLambdaParameter = env.tree.hasTag(LAMBDA) && 1059 ((JCLambda)env.tree).paramKind == JCLambda.ParameterKind.IMPLICIT && 1060 (tree.sym.flags() & PARAMETER) != 0; 1061 chk.validate(tree.vartype, env, !isImplicitLambdaParameter); 1062 deferredLintHandler.flush(tree.pos()); 1063 1064 try { 1065 chk.checkDeprecatedAnnotation(tree.pos(), v); 1066 1067 if (tree.init != null) { 1068 if ((v.flags_field & FINAL) != 0 && 1069 !tree.init.hasTag(NEWCLASS) && 1070 !tree.init.hasTag(LAMBDA) && 1071 !tree.init.hasTag(REFERENCE)) { 1072 // In this case, `v' is final. Ensure that it's initializer is 1073 // evaluated. 1074 v.getConstValue(); // ensure initializer is evaluated 1075 } else { 1076 // Attribute initializer in a new environment 1077 // with the declared variable as owner. 1078 // Check that initializer conforms to variable's declared type. 1079 Env<AttrContext> initEnv = memberEnter.initEnv(tree, env); 1080 initEnv.info.lint = lint; 1081 // In order to catch self-references, we set the variable's 1082 // declaration position to maximal possible value, effectively 1083 // marking the variable as undefined. 1084 initEnv.info.enclVar = v; 1085 attribExpr(tree.init, initEnv, v.type); 1086 } 1087 } 1088 result = tree.type = v.type; 1089 chk.validateAnnotations(tree.mods.annotations, v); 1090 } 1091 finally { 1092 chk.setLint(prevLint); 1093 } 1094 } 1095 1096 public void visitSkip(JCSkip tree) { 1097 result = null; 1098 } 1099 1100 public void visitBlock(JCBlock tree) { 1101 if (env.info.scope.owner.kind == TYP) { 1102 // Block is a static or instance initializer; 1103 // let the owner of the environment be a freshly 1104 // created BLOCK-method. 1105 Env<AttrContext> localEnv = 1106 env.dup(tree, env.info.dup(env.info.scope.dupUnshared())); 1107 localEnv.info.scope.owner = 1108 new MethodSymbol(tree.flags | BLOCK | 1109 env.info.scope.owner.flags() & STRICTFP, names.empty, null, 1110 env.info.scope.owner); 1111 if ((tree.flags & STATIC) != 0) localEnv.info.staticLevel++; 1112 1113 // Attribute all type annotations in the block 1114 memberEnter.typeAnnotate(tree, localEnv, localEnv.info.scope.owner); 1115 annotate.flush(); 1116 1117 { 1118 // Store init and clinit type annotations with the ClassSymbol 1119 // to allow output in Gen.normalizeDefs. 1120 ClassSymbol cs = (ClassSymbol)env.info.scope.owner; 1121 List<Attribute.TypeCompound> tas = localEnv.info.scope.owner.getRawTypeAttributes(); 1122 if ((tree.flags & STATIC) != 0) { 1123 cs.appendClassInitTypeAttributes(tas); 1124 } else { 1125 cs.appendInitTypeAttributes(tas); 1126 } 1127 } 1128 1129 attribStats(tree.stats, localEnv); 1130 } else { 1131 // Create a new local environment with a local scope. 1132 Env<AttrContext> localEnv = 1133 env.dup(tree, env.info.dup(env.info.scope.dup())); 1134 try { 1135 attribStats(tree.stats, localEnv); 1136 } finally { 1137 localEnv.info.scope.leave(); 1138 } 1139 } 1140 result = null; 1141 } 1142 1143 public void visitDoLoop(JCDoWhileLoop tree) { 1144 attribStat(tree.body, env.dup(tree)); 1145 attribExpr(tree.cond, env, syms.booleanType); 1146 result = null; 1147 } 1148 1149 public void visitWhileLoop(JCWhileLoop tree) { 1150 attribExpr(tree.cond, env, syms.booleanType); 1151 attribStat(tree.body, env.dup(tree)); 1152 result = null; 1153 } 1154 1155 public void visitForLoop(JCForLoop tree) { 1156 Env<AttrContext> loopEnv = 1157 env.dup(env.tree, env.info.dup(env.info.scope.dup())); 1158 try { 1159 attribStats(tree.init, loopEnv); 1160 if (tree.cond != null) attribExpr(tree.cond, loopEnv, syms.booleanType); 1161 loopEnv.tree = tree; // before, we were not in loop! 1162 attribStats(tree.step, loopEnv); 1163 attribStat(tree.body, loopEnv); 1164 result = null; 1165 } 1166 finally { 1167 loopEnv.info.scope.leave(); 1168 } 1169 } 1170 1171 public void visitForeachLoop(JCEnhancedForLoop tree) { 1172 Env<AttrContext> loopEnv = 1173 env.dup(env.tree, env.info.dup(env.info.scope.dup())); 1174 try { 1175 //the Formal Parameter of a for-each loop is not in the scope when 1176 //attributing the for-each expression; we mimick this by attributing 1177 //the for-each expression first (against original scope). 1178 Type exprType = types.upperBound(attribExpr(tree.expr, loopEnv)); 1179 attribStat(tree.var, loopEnv); 1180 chk.checkNonVoid(tree.pos(), exprType); 1181 Type elemtype = types.elemtype(exprType); // perhaps expr is an array? 1182 if (elemtype == null) { 1183 // or perhaps expr implements Iterable<T>? 1184 Type base = types.asSuper(exprType, syms.iterableType.tsym); 1185 if (base == null) { 1186 log.error(tree.expr.pos(), 1187 "foreach.not.applicable.to.type", 1188 exprType, 1189 diags.fragment("type.req.array.or.iterable")); 1190 elemtype = types.createErrorType(exprType); 1191 } else { 1192 List<Type> iterableParams = base.allparams(); 1193 elemtype = iterableParams.isEmpty() 1194 ? syms.objectType 1195 : types.upperBound(iterableParams.head); 1196 } 1197 } 1198 chk.checkType(tree.expr.pos(), elemtype, tree.var.sym.type); 1199 loopEnv.tree = tree; // before, we were not in loop! 1200 attribStat(tree.body, loopEnv); 1201 result = null; 1202 } 1203 finally { 1204 loopEnv.info.scope.leave(); 1205 } 1206 } 1207 1208 public void visitLabelled(JCLabeledStatement tree) { 1209 // Check that label is not used in an enclosing statement 1210 Env<AttrContext> env1 = env; 1211 while (env1 != null && !env1.tree.hasTag(CLASSDEF)) { 1212 if (env1.tree.hasTag(LABELLED) && 1213 ((JCLabeledStatement) env1.tree).label == tree.label) { 1214 log.error(tree.pos(), "label.already.in.use", 1215 tree.label); 1216 break; 1217 } 1218 env1 = env1.next; 1219 } 1220 1221 attribStat(tree.body, env.dup(tree)); 1222 result = null; 1223 } 1224 1225 public void visitSwitch(JCSwitch tree) { 1226 Type seltype = attribExpr(tree.selector, env); 1227 1228 Env<AttrContext> switchEnv = 1229 env.dup(tree, env.info.dup(env.info.scope.dup())); 1230 1231 try { 1232 1233 boolean enumSwitch = 1234 allowEnums && 1235 (seltype.tsym.flags() & Flags.ENUM) != 0; 1236 boolean stringSwitch = false; 1237 if (types.isSameType(seltype, syms.stringType)) { 1238 if (allowStringsInSwitch) { 1239 stringSwitch = true; 1240 } else { 1241 log.error(tree.selector.pos(), "string.switch.not.supported.in.source", sourceName); 1242 } 1243 } 1244 if (!enumSwitch && !stringSwitch) 1245 seltype = chk.checkType(tree.selector.pos(), seltype, syms.intType); 1246 1247 // Attribute all cases and 1248 // check that there are no duplicate case labels or default clauses. 1249 Set<Object> labels = new HashSet<Object>(); // The set of case labels. 1250 boolean hasDefault = false; // Is there a default label? 1251 for (List<JCCase> l = tree.cases; l.nonEmpty(); l = l.tail) { 1252 JCCase c = l.head; 1253 Env<AttrContext> caseEnv = 1254 switchEnv.dup(c, env.info.dup(switchEnv.info.scope.dup())); 1255 try { 1256 if (c.pat != null) { 1257 if (enumSwitch) { 1258 Symbol sym = enumConstant(c.pat, seltype); 1259 if (sym == null) { 1260 log.error(c.pat.pos(), "enum.label.must.be.unqualified.enum"); 1261 } else if (!labels.add(sym)) { 1262 log.error(c.pos(), "duplicate.case.label"); 1263 } 1264 } else { 1265 Type pattype = attribExpr(c.pat, switchEnv, seltype); 1266 if (!pattype.hasTag(ERROR)) { 1267 if (pattype.constValue() == null) { 1268 log.error(c.pat.pos(), 1269 (stringSwitch ? "string.const.req" : "const.expr.req")); 1270 } else if (labels.contains(pattype.constValue())) { 1271 log.error(c.pos(), "duplicate.case.label"); 1272 } else { 1273 labels.add(pattype.constValue()); 1274 } 1275 } 1276 } 1277 } else if (hasDefault) { 1278 log.error(c.pos(), "duplicate.default.label"); 1279 } else { 1280 hasDefault = true; 1281 } 1282 attribStats(c.stats, caseEnv); 1283 } finally { 1284 caseEnv.info.scope.leave(); 1285 addVars(c.stats, switchEnv.info.scope); 1286 } 1287 } 1288 1289 result = null; 1290 } 1291 finally { 1292 switchEnv.info.scope.leave(); 1293 } 1294 } 1295 // where 1296 /** Add any variables defined in stats to the switch scope. */ 1297 private static void addVars(List<JCStatement> stats, Scope switchScope) { 1298 for (;stats.nonEmpty(); stats = stats.tail) { 1299 JCTree stat = stats.head; 1300 if (stat.hasTag(VARDEF)) 1301 switchScope.enter(((JCVariableDecl) stat).sym); 1302 } 1303 } 1304 // where 1305 /** Return the selected enumeration constant symbol, or null. */ 1306 private Symbol enumConstant(JCTree tree, Type enumType) { 1307 if (!tree.hasTag(IDENT)) { 1308 log.error(tree.pos(), "enum.label.must.be.unqualified.enum"); 1309 return syms.errSymbol; 1310 } 1311 JCIdent ident = (JCIdent)tree; 1312 Name name = ident.name; 1313 for (Scope.Entry e = enumType.tsym.members().lookup(name); 1314 e.scope != null; e = e.next()) { 1315 if (e.sym.kind == VAR) { 1316 Symbol s = ident.sym = e.sym; 1317 ((VarSymbol)s).getConstValue(); // ensure initializer is evaluated 1318 ident.type = s.type; 1319 return ((s.flags_field & Flags.ENUM) == 0) 1320 ? null : s; 1321 } 1322 } 1323 return null; 1324 } 1325 1326 public void visitSynchronized(JCSynchronized tree) { 1327 chk.checkRefType(tree.pos(), attribExpr(tree.lock, env)); 1328 attribStat(tree.body, env); 1329 result = null; 1330 } 1331 1332 public void visitTry(JCTry tree) { 1333 // Create a new local environment with a local 1334 Env<AttrContext> localEnv = env.dup(tree, env.info.dup(env.info.scope.dup())); 1335 try { 1336 boolean isTryWithResource = tree.resources.nonEmpty(); 1337 // Create a nested environment for attributing the try block if needed 1338 Env<AttrContext> tryEnv = isTryWithResource ? 1339 env.dup(tree, localEnv.info.dup(localEnv.info.scope.dup())) : 1340 localEnv; 1341 try { 1342 // Attribute resource declarations 1343 for (JCTree resource : tree.resources) { 1344 CheckContext twrContext = new Check.NestedCheckContext(resultInfo.checkContext) { 1345 @Override 1346 public void report(DiagnosticPosition pos, JCDiagnostic details) { 1347 chk.basicHandler.report(pos, diags.fragment("try.not.applicable.to.type", details)); 1348 } 1349 }; 1350 ResultInfo twrResult = new ResultInfo(VAL, syms.autoCloseableType, twrContext); 1351 if (resource.hasTag(VARDEF)) { 1352 attribStat(resource, tryEnv); 1353 twrResult.check(resource, resource.type); 1354 1355 //check that resource type cannot throw InterruptedException 1356 checkAutoCloseable(resource.pos(), localEnv, resource.type); 1357 1358 VarSymbol var = ((JCVariableDecl) resource).sym; 1359 var.setData(ElementKind.RESOURCE_VARIABLE); 1360 } else { 1361 attribTree(resource, tryEnv, twrResult); 1362 } 1363 } 1364 // Attribute body 1365 attribStat(tree.body, tryEnv); 1366 } finally { 1367 if (isTryWithResource) 1368 tryEnv.info.scope.leave(); 1369 } 1370 1371 // Attribute catch clauses 1372 for (List<JCCatch> l = tree.catchers; l.nonEmpty(); l = l.tail) { 1373 JCCatch c = l.head; 1374 Env<AttrContext> catchEnv = 1375 localEnv.dup(c, localEnv.info.dup(localEnv.info.scope.dup())); 1376 try { 1377 Type ctype = attribStat(c.param, catchEnv); 1378 if (TreeInfo.isMultiCatch(c)) { 1379 //multi-catch parameter is implicitly marked as final 1380 c.param.sym.flags_field |= FINAL | UNION; 1381 } 1382 if (c.param.sym.kind == Kinds.VAR) { 1383 c.param.sym.setData(ElementKind.EXCEPTION_PARAMETER); 1384 } 1385 chk.checkType(c.param.vartype.pos(), 1386 chk.checkClassType(c.param.vartype.pos(), ctype), 1387 syms.throwableType); 1388 attribStat(c.body, catchEnv); 1389 } finally { 1390 catchEnv.info.scope.leave(); 1391 } 1392 } 1393 1394 // Attribute finalizer 1395 if (tree.finalizer != null) attribStat(tree.finalizer, localEnv); 1396 result = null; 1397 } 1398 finally { 1399 localEnv.info.scope.leave(); 1400 } 1401 } 1402 1403 void checkAutoCloseable(DiagnosticPosition pos, Env<AttrContext> env, Type resource) { 1404 if (!resource.isErroneous() && 1405 types.asSuper(resource, syms.autoCloseableType.tsym) != null && 1406 !types.isSameType(resource, syms.autoCloseableType)) { // Don't emit warning for AutoCloseable itself 1407 Symbol close = syms.noSymbol; 1408 Log.DiagnosticHandler discardHandler = new Log.DiscardDiagnosticHandler(log); 1409 try { 1410 close = rs.resolveQualifiedMethod(pos, 1411 env, 1412 resource, 1413 names.close, 1414 List.<Type>nil(), 1415 List.<Type>nil()); 1416 } 1417 finally { 1418 log.popDiagnosticHandler(discardHandler); 1419 } 1420 if (close.kind == MTH && 1421 close.overrides(syms.autoCloseableClose, resource.tsym, types, true) && 1422 chk.isHandled(syms.interruptedExceptionType, types.memberType(resource, close).getThrownTypes()) && 1423 env.info.lint.isEnabled(LintCategory.TRY)) { 1424 log.warning(LintCategory.TRY, pos, "try.resource.throws.interrupted.exc", resource); 1425 } 1426 } 1427 } 1428 1429 public void visitConditional(JCConditional tree) { 1430 Type condtype = attribExpr(tree.cond, env, syms.booleanType); 1431 1432 tree.polyKind = (!allowPoly || 1433 pt().hasTag(NONE) && pt() != Type.recoveryType || 1434 isBooleanOrNumeric(env, tree)) ? 1435 PolyKind.STANDALONE : PolyKind.POLY; 1436 1437 if (tree.polyKind == PolyKind.POLY && resultInfo.pt.hasTag(VOID)) { 1438 //cannot get here (i.e. it means we are returning from void method - which is already an error) 1439 resultInfo.checkContext.report(tree, diags.fragment("conditional.target.cant.be.void")); 1440 result = tree.type = types.createErrorType(resultInfo.pt); 1441 return; 1442 } 1443 1444 ResultInfo condInfo = tree.polyKind == PolyKind.STANDALONE ? 1445 unknownExprInfo : 1446 resultInfo.dup(new Check.NestedCheckContext(resultInfo.checkContext) { 1447 //this will use enclosing check context to check compatibility of 1448 //subexpression against target type; if we are in a method check context, 1449 //depending on whether boxing is allowed, we could have incompatibilities 1450 @Override 1451 public void report(DiagnosticPosition pos, JCDiagnostic details) { 1452 enclosingContext.report(pos, diags.fragment("incompatible.type.in.conditional", details)); 1453 } 1454 }); 1455 1456 Type truetype = attribTree(tree.truepart, env, condInfo); 1457 Type falsetype = attribTree(tree.falsepart, env, condInfo); 1458 1459 Type owntype = (tree.polyKind == PolyKind.STANDALONE) ? condType(tree, truetype, falsetype) : pt(); 1460 if (condtype.constValue() != null && 1461 truetype.constValue() != null && 1462 falsetype.constValue() != null && 1463 !owntype.hasTag(NONE)) { 1464 //constant folding 1465 owntype = cfolder.coerce(condtype.isTrue() ? truetype : falsetype, owntype); 1466 } 1467 result = check(tree, owntype, VAL, resultInfo); 1468 } 1469 //where 1470 private boolean isBooleanOrNumeric(Env<AttrContext> env, JCExpression tree) { 1471 switch (tree.getTag()) { 1472 case LITERAL: return ((JCLiteral)tree).typetag.isSubRangeOf(DOUBLE) || 1473 ((JCLiteral)tree).typetag == BOOLEAN || 1474 ((JCLiteral)tree).typetag == BOT; 1475 case LAMBDA: case REFERENCE: return false; 1476 case PARENS: return isBooleanOrNumeric(env, ((JCParens)tree).expr); 1477 case CONDEXPR: 1478 JCConditional condTree = (JCConditional)tree; 1479 return isBooleanOrNumeric(env, condTree.truepart) && 1480 isBooleanOrNumeric(env, condTree.falsepart); 1481 case APPLY: 1482 JCMethodInvocation speculativeMethodTree = 1483 (JCMethodInvocation)deferredAttr.attribSpeculative(tree, env, unknownExprInfo); 1484 Type owntype = TreeInfo.symbol(speculativeMethodTree.meth).type.getReturnType(); 1485 return types.unboxedTypeOrType(owntype).isPrimitive(); 1486 case NEWCLASS: 1487 JCExpression className = 1488 removeClassParams.translate(((JCNewClass)tree).clazz); 1489 JCExpression speculativeNewClassTree = 1490 (JCExpression)deferredAttr.attribSpeculative(className, env, unknownTypeInfo); 1491 return types.unboxedTypeOrType(speculativeNewClassTree.type).isPrimitive(); 1492 default: 1493 Type speculativeType = deferredAttr.attribSpeculative(tree, env, unknownExprInfo).type; 1494 speculativeType = types.unboxedTypeOrType(speculativeType); 1495 return speculativeType.isPrimitive(); 1496 } 1497 } 1498 //where 1499 TreeTranslator removeClassParams = new TreeTranslator() { 1500 @Override 1501 public void visitTypeApply(JCTypeApply tree) { 1502 result = translate(tree.clazz); 1503 } 1504 }; 1505 1506 /** Compute the type of a conditional expression, after 1507 * checking that it exists. See JLS 15.25. Does not take into 1508 * account the special case where condition and both arms 1509 * are constants. 1510 * 1511 * @param pos The source position to be used for error 1512 * diagnostics. 1513 * @param thentype The type of the expression's then-part. 1514 * @param elsetype The type of the expression's else-part. 1515 */ 1516 private Type condType(DiagnosticPosition pos, 1517 Type thentype, Type elsetype) { 1518 // If same type, that is the result 1519 if (types.isSameType(thentype, elsetype)) 1520 return thentype.baseType(); 1521 1522 Type thenUnboxed = (!allowBoxing || thentype.isPrimitive()) 1523 ? thentype : types.unboxedType(thentype); 1524 Type elseUnboxed = (!allowBoxing || elsetype.isPrimitive()) 1525 ? elsetype : types.unboxedType(elsetype); 1526 1527 // Otherwise, if both arms can be converted to a numeric 1528 // type, return the least numeric type that fits both arms 1529 // (i.e. return larger of the two, or return int if one 1530 // arm is short, the other is char). 1531 if (thenUnboxed.isPrimitive() && elseUnboxed.isPrimitive()) { 1532 // If one arm has an integer subrange type (i.e., byte, 1533 // short, or char), and the other is an integer constant 1534 // that fits into the subrange, return the subrange type. 1535 if (thenUnboxed.getTag().isStrictSubRangeOf(INT) && elseUnboxed.hasTag(INT) && 1536 types.isAssignable(elseUnboxed, thenUnboxed)) 1537 return thenUnboxed.baseType(); 1538 if (elseUnboxed.getTag().isStrictSubRangeOf(INT) && thenUnboxed.hasTag(INT) && 1539 types.isAssignable(thenUnboxed, elseUnboxed)) 1540 return elseUnboxed.baseType(); 1541 1542 for (TypeTag tag : TypeTag.values()) { 1543 if (tag.ordinal() >= TypeTag.getTypeTagCount()) break; 1544 Type candidate = syms.typeOfTag[tag.ordinal()]; 1545 if (candidate != null && 1546 candidate.isPrimitive() && 1547 types.isSubtype(thenUnboxed, candidate) && 1548 types.isSubtype(elseUnboxed, candidate)) 1549 return candidate; 1550 } 1551 } 1552 1553 // Those were all the cases that could result in a primitive 1554 if (allowBoxing) { 1555 if (thentype.isPrimitive()) 1556 thentype = types.boxedClass(thentype).type; 1557 if (elsetype.isPrimitive()) 1558 elsetype = types.boxedClass(elsetype).type; 1559 } 1560 1561 if (types.isSubtype(thentype, elsetype)) 1562 return elsetype.baseType(); 1563 if (types.isSubtype(elsetype, thentype)) 1564 return thentype.baseType(); 1565 1566 if (!allowBoxing || thentype.hasTag(VOID) || elsetype.hasTag(VOID)) { 1567 log.error(pos, "neither.conditional.subtype", 1568 thentype, elsetype); 1569 return thentype.baseType(); 1570 } 1571 1572 // both are known to be reference types. The result is 1573 // lub(thentype,elsetype). This cannot fail, as it will 1574 // always be possible to infer "Object" if nothing better. 1575 return types.lub(thentype.baseType(), elsetype.baseType()); 1576 } 1577 1578 public void visitIf(JCIf tree) { 1579 attribExpr(tree.cond, env, syms.booleanType); 1580 attribStat(tree.thenpart, env); 1581 if (tree.elsepart != null) 1582 attribStat(tree.elsepart, env); 1583 chk.checkEmptyIf(tree); 1584 result = null; 1585 } 1586 1587 public void visitExec(JCExpressionStatement tree) { 1588 //a fresh environment is required for 292 inference to work properly --- 1589 //see Infer.instantiatePolymorphicSignatureInstance() 1590 Env<AttrContext> localEnv = env.dup(tree); 1591 attribExpr(tree.expr, localEnv); 1592 result = null; 1593 } 1594 1595 public void visitBreak(JCBreak tree) { 1596 tree.target = findJumpTarget(tree.pos(), tree.getTag(), tree.label, env); 1597 result = null; 1598 } 1599 1600 public void visitContinue(JCContinue tree) { 1601 tree.target = findJumpTarget(tree.pos(), tree.getTag(), tree.label, env); 1602 result = null; 1603 } 1604 //where 1605 /** Return the target of a break or continue statement, if it exists, 1606 * report an error if not. 1607 * Note: The target of a labelled break or continue is the 1608 * (non-labelled) statement tree referred to by the label, 1609 * not the tree representing the labelled statement itself. 1610 * 1611 * @param pos The position to be used for error diagnostics 1612 * @param tag The tag of the jump statement. This is either 1613 * Tree.BREAK or Tree.CONTINUE. 1614 * @param label The label of the jump statement, or null if no 1615 * label is given. 1616 * @param env The environment current at the jump statement. 1617 */ 1618 private JCTree findJumpTarget(DiagnosticPosition pos, 1619 JCTree.Tag tag, 1620 Name label, 1621 Env<AttrContext> env) { 1622 // Search environments outwards from the point of jump. 1623 Env<AttrContext> env1 = env; 1624 LOOP: 1625 while (env1 != null) { 1626 switch (env1.tree.getTag()) { 1627 case LABELLED: 1628 JCLabeledStatement labelled = (JCLabeledStatement)env1.tree; 1629 if (label == labelled.label) { 1630 // If jump is a continue, check that target is a loop. 1631 if (tag == CONTINUE) { 1632 if (!labelled.body.hasTag(DOLOOP) && 1633 !labelled.body.hasTag(WHILELOOP) && 1634 !labelled.body.hasTag(FORLOOP) && 1635 !labelled.body.hasTag(FOREACHLOOP)) 1636 log.error(pos, "not.loop.label", label); 1637 // Found labelled statement target, now go inwards 1638 // to next non-labelled tree. 1639 return TreeInfo.referencedStatement(labelled); 1640 } else { 1641 return labelled; 1642 } 1643 } 1644 break; 1645 case DOLOOP: 1646 case WHILELOOP: 1647 case FORLOOP: 1648 case FOREACHLOOP: 1649 if (label == null) return env1.tree; 1650 break; 1651 case SWITCH: 1652 if (label == null && tag == BREAK) return env1.tree; 1653 break; 1654 case LAMBDA: 1655 case METHODDEF: 1656 case CLASSDEF: 1657 break LOOP; 1658 default: 1659 } 1660 env1 = env1.next; 1661 } 1662 if (label != null) 1663 log.error(pos, "undef.label", label); 1664 else if (tag == CONTINUE) 1665 log.error(pos, "cont.outside.loop"); 1666 else 1667 log.error(pos, "break.outside.switch.loop"); 1668 return null; 1669 } 1670 1671 public void visitReturn(JCReturn tree) { 1672 // Check that there is an enclosing method which is 1673 // nested within than the enclosing class. 1674 if (env.info.returnResult == null) { 1675 log.error(tree.pos(), "ret.outside.meth"); 1676 } else { 1677 // Attribute return expression, if it exists, and check that 1678 // it conforms to result type of enclosing method. 1679 if (tree.expr != null) { 1680 if (env.info.returnResult.pt.hasTag(VOID)) { 1681 env.info.returnResult.checkContext.report(tree.expr.pos(), 1682 diags.fragment("unexpected.ret.val")); 1683 } 1684 attribTree(tree.expr, env, env.info.returnResult); 1685 } else if (!env.info.returnResult.pt.hasTag(VOID)) { 1686 env.info.returnResult.checkContext.report(tree.pos(), 1687 diags.fragment("missing.ret.val")); 1688 } 1689 } 1690 result = null; 1691 } 1692 1693 public void visitThrow(JCThrow tree) { 1694 Type owntype = attribExpr(tree.expr, env, allowPoly ? Type.noType : syms.throwableType); 1695 if (allowPoly) { 1696 chk.checkType(tree, owntype, syms.throwableType); 1697 } 1698 result = null; 1699 } 1700 1701 public void visitAssert(JCAssert tree) { 1702 attribExpr(tree.cond, env, syms.booleanType); 1703 if (tree.detail != null) { 1704 chk.checkNonVoid(tree.detail.pos(), attribExpr(tree.detail, env)); 1705 } 1706 result = null; 1707 } 1708 1709 /** Visitor method for method invocations. 1710 * NOTE: The method part of an application will have in its type field 1711 * the return type of the method, not the method's type itself! 1712 */ 1713 public void visitApply(JCMethodInvocation tree) { 1714 // The local environment of a method application is 1715 // a new environment nested in the current one. 1716 Env<AttrContext> localEnv = env.dup(tree, env.info.dup()); 1717 1718 // The types of the actual method arguments. 1719 List<Type> argtypes; 1720 1721 // The types of the actual method type arguments. 1722 List<Type> typeargtypes = null; 1723 1724 Name methName = TreeInfo.name(tree.meth); 1725 1726 boolean isConstructorCall = 1727 methName == names._this || methName == names._super; 1728 1729 if (isConstructorCall) { 1730 // We are seeing a ...this(...) or ...super(...) call. 1731 // Check that this is the first statement in a constructor. 1732 if (checkFirstConstructorStat(tree, env)) { 1733 1734 // Record the fact 1735 // that this is a constructor call (using isSelfCall). 1736 localEnv.info.isSelfCall = true; 1737 1738 // Attribute arguments, yielding list of argument types. 1739 argtypes = attribArgs(tree.args, localEnv); 1740 typeargtypes = attribTypes(tree.typeargs, localEnv); 1741 1742 // Variable `site' points to the class in which the called 1743 // constructor is defined. 1744 Type site = env.enclClass.sym.type; 1745 if (methName == names._super) { 1746 if (site == syms.objectType) { 1747 log.error(tree.meth.pos(), "no.superclass", site); 1748 site = types.createErrorType(syms.objectType); 1749 } else { 1750 site = types.supertype(site); 1751 } 1752 } 1753 1754 if (site.hasTag(CLASS)) { 1755 Type encl = site.getEnclosingType(); 1756 while (encl != null && encl.hasTag(TYPEVAR)) 1757 encl = encl.getUpperBound(); 1758 if (encl.hasTag(CLASS)) { 1759 // we are calling a nested class 1760 1761 if (tree.meth.hasTag(SELECT)) { 1762 JCTree qualifier = ((JCFieldAccess) tree.meth).selected; 1763 1764 // We are seeing a prefixed call, of the form 1765 // <expr>.super(...). 1766 // Check that the prefix expression conforms 1767 // to the outer instance type of the class. 1768 chk.checkRefType(qualifier.pos(), 1769 attribExpr(qualifier, localEnv, 1770 encl)); 1771 } else if (methName == names._super) { 1772 // qualifier omitted; check for existence 1773 // of an appropriate implicit qualifier. 1774 rs.resolveImplicitThis(tree.meth.pos(), 1775 localEnv, site, true); 1776 } 1777 } else if (tree.meth.hasTag(SELECT)) { 1778 log.error(tree.meth.pos(), "illegal.qual.not.icls", 1779 site.tsym); 1780 } 1781 1782 // if we're calling a java.lang.Enum constructor, 1783 // prefix the implicit String and int parameters 1784 if (site.tsym == syms.enumSym && allowEnums) 1785 argtypes = argtypes.prepend(syms.intType).prepend(syms.stringType); 1786 1787 // Resolve the called constructor under the assumption 1788 // that we are referring to a superclass instance of the 1789 // current instance (JLS ???). 1790 boolean selectSuperPrev = localEnv.info.selectSuper; 1791 localEnv.info.selectSuper = true; 1792 localEnv.info.pendingResolutionPhase = null; 1793 Symbol sym = rs.resolveConstructor( 1794 tree.meth.pos(), localEnv, site, argtypes, typeargtypes); 1795 localEnv.info.selectSuper = selectSuperPrev; 1796 1797 // Set method symbol to resolved constructor... 1798 TreeInfo.setSymbol(tree.meth, sym); 1799 1800 // ...and check that it is legal in the current context. 1801 // (this will also set the tree's type) 1802 Type mpt = newMethodTemplate(resultInfo.pt, argtypes, typeargtypes); 1803 checkId(tree.meth, site, sym, localEnv, new ResultInfo(MTH, mpt)); 1804 } 1805 // Otherwise, `site' is an error type and we do nothing 1806 } 1807 result = tree.type = syms.voidType; 1808 } else { 1809 // Otherwise, we are seeing a regular method call. 1810 // Attribute the arguments, yielding list of argument types, ... 1811 argtypes = attribArgs(tree.args, localEnv); 1812 typeargtypes = attribAnyTypes(tree.typeargs, localEnv); 1813 1814 // ... and attribute the method using as a prototype a methodtype 1815 // whose formal argument types is exactly the list of actual 1816 // arguments (this will also set the method symbol). 1817 Type mpt = newMethodTemplate(resultInfo.pt, argtypes, typeargtypes); 1818 localEnv.info.pendingResolutionPhase = null; 1819 Type mtype = attribTree(tree.meth, localEnv, new ResultInfo(VAL, mpt, resultInfo.checkContext)); 1820 1821 // Compute the result type. 1822 Type restype = mtype.getReturnType(); 1823 if (restype.hasTag(WILDCARD)) 1824 throw new AssertionError(mtype); 1825 1826 Type qualifier = (tree.meth.hasTag(SELECT)) 1827 ? ((JCFieldAccess) tree.meth).selected.type 1828 : env.enclClass.sym.type; 1829 restype = adjustMethodReturnType(qualifier, methName, argtypes, restype); 1830 1831 chk.checkRefTypes(tree.typeargs, typeargtypes); 1832 1833 // Check that value of resulting type is admissible in the 1834 // current context. Also, capture the return type 1835 result = check(tree, capture(restype), VAL, resultInfo); 1836 } 1837 chk.validate(tree.typeargs, localEnv); 1838 } 1839 //where 1840 Type adjustMethodReturnType(Type qualifierType, Name methodName, List<Type> argtypes, Type restype) { 1841 if (allowCovariantReturns && 1842 methodName == names.clone && 1843 types.isArray(qualifierType)) { 1844 // as a special case, array.clone() has a result that is 1845 // the same as static type of the array being cloned 1846 return qualifierType; 1847 } else if (allowGenerics && 1848 methodName == names.getClass && 1849 argtypes.isEmpty()) { 1850 // as a special case, x.getClass() has type Class<? extends |X|> 1851 return new ClassType(restype.getEnclosingType(), 1852 List.<Type>of(new WildcardType(types.erasure(qualifierType), 1853 BoundKind.EXTENDS, 1854 syms.boundClass)), 1855 restype.tsym); 1856 } else { 1857 return restype; 1858 } 1859 } 1860 1861 /** Check that given application node appears as first statement 1862 * in a constructor call. 1863 * @param tree The application node 1864 * @param env The environment current at the application. 1865 */ 1866 boolean checkFirstConstructorStat(JCMethodInvocation tree, Env<AttrContext> env) { 1867 JCMethodDecl enclMethod = env.enclMethod; 1868 if (enclMethod != null && enclMethod.name == names.init) { 1869 JCBlock body = enclMethod.body; 1870 if (body.stats.head.hasTag(EXEC) && 1871 ((JCExpressionStatement) body.stats.head).expr == tree) 1872 return true; 1873 } 1874 log.error(tree.pos(),"call.must.be.first.stmt.in.ctor", 1875 TreeInfo.name(tree.meth)); 1876 return false; 1877 } 1878 1879 /** Obtain a method type with given argument types. 1880 */ 1881 Type newMethodTemplate(Type restype, List<Type> argtypes, List<Type> typeargtypes) { 1882 MethodType mt = new MethodType(argtypes, restype, List.<Type>nil(), syms.methodClass); 1883 return (typeargtypes == null) ? mt : (Type)new ForAll(typeargtypes, mt); 1884 } 1885 1886 public void visitNewClass(final JCNewClass tree) { 1887 Type owntype = types.createErrorType(tree.type); 1888 1889 // The local environment of a class creation is 1890 // a new environment nested in the current one. 1891 Env<AttrContext> localEnv = env.dup(tree, env.info.dup()); 1892 1893 // The anonymous inner class definition of the new expression, 1894 // if one is defined by it. 1895 JCClassDecl cdef = tree.def; 1896 1897 // If enclosing class is given, attribute it, and 1898 // complete class name to be fully qualified 1899 JCExpression clazz = tree.clazz; // Class field following new 1900 JCExpression clazzid; // Identifier in class field 1901 JCAnnotatedType annoclazzid; // Annotated type enclosing clazzid 1902 annoclazzid = null; 1903 1904 if (clazz.hasTag(TYPEAPPLY)) { 1905 clazzid = ((JCTypeApply) clazz).clazz; 1906 if (clazzid.hasTag(ANNOTATED_TYPE)) { 1907 annoclazzid = (JCAnnotatedType) clazzid; 1908 clazzid = annoclazzid.underlyingType; 1909 } 1910 } else { 1911 if (clazz.hasTag(ANNOTATED_TYPE)) { 1912 annoclazzid = (JCAnnotatedType) clazz; 1913 clazzid = annoclazzid.underlyingType; 1914 } else { 1915 clazzid = clazz; 1916 } 1917 } 1918 1919 JCExpression clazzid1 = clazzid; // The same in fully qualified form 1920 1921 if (tree.encl != null) { 1922 // We are seeing a qualified new, of the form 1923 // <expr>.new C <...> (...) ... 1924 // In this case, we let clazz stand for the name of the 1925 // allocated class C prefixed with the type of the qualifier 1926 // expression, so that we can 1927 // resolve it with standard techniques later. I.e., if 1928 // <expr> has type T, then <expr>.new C <...> (...) 1929 // yields a clazz T.C. 1930 Type encltype = chk.checkRefType(tree.encl.pos(), 1931 attribExpr(tree.encl, env)); 1932 // TODO 308: in <expr>.new C, do we also want to add the type annotations 1933 // from expr to the combined type, or not? Yes, do this. 1934 clazzid1 = make.at(clazz.pos).Select(make.Type(encltype), 1935 ((JCIdent) clazzid).name); 1936 1937 if (clazz.hasTag(ANNOTATED_TYPE)) { 1938 JCAnnotatedType annoType = (JCAnnotatedType) clazz; 1939 List<JCAnnotation> annos = annoType.annotations; 1940 1941 if (annoType.underlyingType.hasTag(TYPEAPPLY)) { 1942 clazzid1 = make.at(tree.pos). 1943 TypeApply(clazzid1, 1944 ((JCTypeApply) clazz).arguments); 1945 } 1946 1947 clazzid1 = make.at(tree.pos). 1948 AnnotatedType(annos, clazzid1); 1949 } else if (clazz.hasTag(TYPEAPPLY)) { 1950 clazzid1 = make.at(tree.pos). 1951 TypeApply(clazzid1, 1952 ((JCTypeApply) clazz).arguments); 1953 } 1954 1955 clazz = clazzid1; 1956 } 1957 1958 // Attribute clazz expression and store 1959 // symbol + type back into the attributed tree. 1960 Type clazztype = TreeInfo.isEnumInit(env.tree) ? 1961 attribIdentAsEnumType(env, (JCIdent)clazz) : 1962 attribType(clazz, env); 1963 1964 clazztype = chk.checkDiamond(tree, clazztype); 1965 chk.validate(clazz, localEnv); 1966 if (tree.encl != null) { 1967 // We have to work in this case to store 1968 // symbol + type back into the attributed tree. 1969 tree.clazz.type = clazztype; 1970 TreeInfo.setSymbol(clazzid, TreeInfo.symbol(clazzid1)); 1971 clazzid.type = ((JCIdent) clazzid).sym.type; 1972 if (annoclazzid != null) { 1973 annoclazzid.type = clazzid.type; 1974 } 1975 if (!clazztype.isErroneous()) { 1976 if (cdef != null && clazztype.tsym.isInterface()) { 1977 log.error(tree.encl.pos(), "anon.class.impl.intf.no.qual.for.new"); 1978 } else if (clazztype.tsym.isStatic()) { 1979 log.error(tree.encl.pos(), "qualified.new.of.static.class", clazztype.tsym); 1980 } 1981 } 1982 } else if (!clazztype.tsym.isInterface() && 1983 clazztype.getEnclosingType().hasTag(CLASS)) { 1984 // Check for the existence of an apropos outer instance 1985 rs.resolveImplicitThis(tree.pos(), env, clazztype); 1986 } 1987 1988 // Attribute constructor arguments. 1989 List<Type> argtypes = attribArgs(tree.args, localEnv); 1990 List<Type> typeargtypes = attribTypes(tree.typeargs, localEnv); 1991 1992 // If we have made no mistakes in the class type... 1993 if (clazztype.hasTag(CLASS)) { 1994 // Enums may not be instantiated except implicitly 1995 if (allowEnums && 1996 (clazztype.tsym.flags_field&Flags.ENUM) != 0 && 1997 (!env.tree.hasTag(VARDEF) || 1998 (((JCVariableDecl) env.tree).mods.flags&Flags.ENUM) == 0 || 1999 ((JCVariableDecl) env.tree).init != tree)) 2000 log.error(tree.pos(), "enum.cant.be.instantiated"); 2001 // Check that class is not abstract 2002 if (cdef == null && 2003 (clazztype.tsym.flags() & (ABSTRACT | INTERFACE)) != 0) { 2004 log.error(tree.pos(), "abstract.cant.be.instantiated", 2005 clazztype.tsym); 2006 } else if (cdef != null && clazztype.tsym.isInterface()) { 2007 // Check that no constructor arguments are given to 2008 // anonymous classes implementing an interface 2009 if (!argtypes.isEmpty()) 2010 log.error(tree.args.head.pos(), "anon.class.impl.intf.no.args"); 2011 2012 if (!typeargtypes.isEmpty()) 2013 log.error(tree.typeargs.head.pos(), "anon.class.impl.intf.no.typeargs"); 2014 2015 // Error recovery: pretend no arguments were supplied. 2016 argtypes = List.nil(); 2017 typeargtypes = List.nil(); 2018 } else if (TreeInfo.isDiamond(tree)) { 2019 ClassType site = new ClassType(clazztype.getEnclosingType(), 2020 clazztype.tsym.type.getTypeArguments(), 2021 clazztype.tsym); 2022 2023 Env<AttrContext> diamondEnv = localEnv.dup(tree); 2024 diamondEnv.info.selectSuper = cdef != null; 2025 diamondEnv.info.pendingResolutionPhase = null; 2026 2027 //if the type of the instance creation expression is a class type 2028 //apply method resolution inference (JLS 15.12.2.7). The return type 2029 //of the resolved constructor will be a partially instantiated type 2030 Symbol constructor = rs.resolveDiamond(tree.pos(), 2031 diamondEnv, 2032 site, 2033 argtypes, 2034 typeargtypes); 2035 tree.constructor = constructor.baseSymbol(); 2036 2037 final TypeSymbol csym = clazztype.tsym; 2038 ResultInfo diamondResult = new ResultInfo(MTH, newMethodTemplate(resultInfo.pt, argtypes, typeargtypes), new Check.NestedCheckContext(resultInfo.checkContext) { 2039 @Override 2040 public void report(DiagnosticPosition _unused, JCDiagnostic details) { 2041 enclosingContext.report(tree.clazz, 2042 diags.fragment("cant.apply.diamond.1", diags.fragment("diamond", csym), details)); 2043 } 2044 }); 2045 Type constructorType = tree.constructorType = types.createErrorType(clazztype); 2046 constructorType = checkId(tree, site, 2047 constructor, 2048 diamondEnv, 2049 diamondResult); 2050 2051 tree.clazz.type = types.createErrorType(clazztype); 2052 if (!constructorType.isErroneous()) { 2053 tree.clazz.type = clazztype = constructorType.getReturnType(); 2054 tree.constructorType = types.createMethodTypeWithReturn(constructorType, syms.voidType); 2055 } 2056 clazztype = chk.checkClassType(tree.clazz, tree.clazz.type, true); 2057 } 2058 2059 // Resolve the called constructor under the assumption 2060 // that we are referring to a superclass instance of the 2061 // current instance (JLS ???). 2062 else { 2063 //the following code alters some of the fields in the current 2064 //AttrContext - hence, the current context must be dup'ed in 2065 //order to avoid downstream failures 2066 Env<AttrContext> rsEnv = localEnv.dup(tree); 2067 rsEnv.info.selectSuper = cdef != null; 2068 rsEnv.info.pendingResolutionPhase = null; 2069 tree.constructor = rs.resolveConstructor( 2070 tree.pos(), rsEnv, clazztype, argtypes, typeargtypes); 2071 if (cdef == null) { //do not check twice! 2072 tree.constructorType = checkId(tree, 2073 clazztype, 2074 tree.constructor, 2075 rsEnv, 2076 new ResultInfo(MTH, newMethodTemplate(syms.voidType, argtypes, typeargtypes))); 2077 if (rsEnv.info.lastResolveVarargs()) 2078 Assert.check(tree.constructorType.isErroneous() || tree.varargsElement != null); 2079 } 2080 findDiamondIfNeeded(localEnv, tree, clazztype); 2081 } 2082 2083 if (cdef != null) { 2084 // We are seeing an anonymous class instance creation. 2085 // In this case, the class instance creation 2086 // expression 2087 // 2088 // E.new <typeargs1>C<typargs2>(args) { ... } 2089 // 2090 // is represented internally as 2091 // 2092 // E . new <typeargs1>C<typargs2>(args) ( class <empty-name> { ... } ) . 2093 // 2094 // This expression is then *transformed* as follows: 2095 // 2096 // (1) add a STATIC flag to the class definition 2097 // if the current environment is static 2098 // (2) add an extends or implements clause 2099 // (3) add a constructor. 2100 // 2101 // For instance, if C is a class, and ET is the type of E, 2102 // the expression 2103 // 2104 // E.new <typeargs1>C<typargs2>(args) { ... } 2105 // 2106 // is translated to (where X is a fresh name and typarams is the 2107 // parameter list of the super constructor): 2108 // 2109 // new <typeargs1>X(<*nullchk*>E, args) where 2110 // X extends C<typargs2> { 2111 // <typarams> X(ET e, args) { 2112 // e.<typeargs1>super(args) 2113 // } 2114 // ... 2115 // } 2116 if (Resolve.isStatic(env)) cdef.mods.flags |= STATIC; 2117 2118 if (clazztype.tsym.isInterface()) { 2119 cdef.implementing = List.of(clazz); 2120 } else { 2121 cdef.extending = clazz; 2122 } 2123 2124 attribStat(cdef, localEnv); 2125 2126 checkLambdaCandidate(tree, cdef.sym, clazztype); 2127 2128 // If an outer instance is given, 2129 // prefix it to the constructor arguments 2130 // and delete it from the new expression 2131 if (tree.encl != null && !clazztype.tsym.isInterface()) { 2132 tree.args = tree.args.prepend(makeNullCheck(tree.encl)); 2133 argtypes = argtypes.prepend(tree.encl.type); 2134 tree.encl = null; 2135 } 2136 2137 // Reassign clazztype and recompute constructor. 2138 clazztype = cdef.sym.type; 2139 Symbol sym = tree.constructor = rs.resolveConstructor( 2140 tree.pos(), localEnv, clazztype, argtypes, typeargtypes); 2141 Assert.check(sym.kind < AMBIGUOUS); 2142 tree.constructor = sym; 2143 tree.constructorType = checkId(tree, 2144 clazztype, 2145 tree.constructor, 2146 localEnv, 2147 new ResultInfo(VAL, newMethodTemplate(syms.voidType, argtypes, typeargtypes))); 2148 } else { 2149 if (tree.clazz.hasTag(ANNOTATED_TYPE)) { 2150 checkForDeclarationAnnotations(((JCAnnotatedType) tree.clazz).annotations, 2151 tree.clazz.type.tsym); 2152 } 2153 } 2154 2155 if (tree.constructor != null && tree.constructor.kind == MTH) 2156 owntype = clazztype; 2157 } 2158 result = check(tree, owntype, VAL, resultInfo); 2159 chk.validate(tree.typeargs, localEnv); 2160 } 2161 //where 2162 void findDiamondIfNeeded(Env<AttrContext> env, JCNewClass tree, Type clazztype) { 2163 if (tree.def == null && 2164 !clazztype.isErroneous() && 2165 clazztype.getTypeArguments().nonEmpty() && 2166 findDiamonds) { 2167 JCTypeApply ta = (JCTypeApply)tree.clazz; 2168 List<JCExpression> prevTypeargs = ta.arguments; 2169 try { 2170 //create a 'fake' diamond AST node by removing type-argument trees 2171 ta.arguments = List.nil(); 2172 ResultInfo findDiamondResult = new ResultInfo(VAL, 2173 resultInfo.checkContext.inferenceContext().free(resultInfo.pt) ? Type.noType : pt()); 2174 Type inferred = deferredAttr.attribSpeculative(tree, env, findDiamondResult).type; 2175 Type polyPt = allowPoly ? 2176 syms.objectType : 2177 clazztype; 2178 if (!inferred.isErroneous() && 2179 types.isAssignable(inferred, pt().hasTag(NONE) ? polyPt : pt(), types.noWarnings)) { 2180 String key = types.isSameType(clazztype, inferred) ? 2181 "diamond.redundant.args" : 2182 "diamond.redundant.args.1"; 2183 log.warning(tree.clazz.pos(), key, clazztype, inferred); 2184 } 2185 } finally { 2186 ta.arguments = prevTypeargs; 2187 } 2188 } 2189 } 2190 2191 private void checkLambdaCandidate(JCNewClass tree, ClassSymbol csym, Type clazztype) { 2192 if (allowLambda && 2193 identifyLambdaCandidate && 2194 clazztype.hasTag(CLASS) && 2195 !pt().hasTag(NONE) && 2196 types.isFunctionalInterface(clazztype.tsym)) { 2197 Symbol descriptor = types.findDescriptorSymbol(clazztype.tsym); 2198 int count = 0; 2199 boolean found = false; 2200 for (Symbol sym : csym.members().getElements()) { 2201 if ((sym.flags() & SYNTHETIC) != 0 || 2202 sym.isConstructor()) continue; 2203 count++; 2204 if (sym.kind != MTH || 2205 !sym.name.equals(descriptor.name)) continue; 2206 Type mtype = types.memberType(clazztype, sym); 2207 if (types.overrideEquivalent(mtype, types.memberType(clazztype, descriptor))) { 2208 found = true; 2209 } 2210 } 2211 if (found && count == 1) { 2212 log.note(tree.def, "potential.lambda.found"); 2213 } 2214 } 2215 } 2216 2217 private void checkForDeclarationAnnotations(List<? extends JCAnnotation> annotations, 2218 Symbol sym) { 2219 // Ensure that no declaration annotations are present. 2220 // Note that a tree type might be an AnnotatedType with 2221 // empty annotations, if only declaration annotations were given. 2222 // This method will raise an error for such a type. 2223 for (JCAnnotation ai : annotations) { 2224 if (TypeAnnotations.annotationType(syms, names, ai.attribute, sym) == TypeAnnotations.AnnotationType.DECLARATION) { 2225 log.error(ai.pos(), "annotation.type.not.applicable"); 2226 } 2227 } 2228 } 2229 2230 2231 /** Make an attributed null check tree. 2232 */ 2233 public JCExpression makeNullCheck(JCExpression arg) { 2234 // optimization: X.this is never null; skip null check 2235 Name name = TreeInfo.name(arg); 2236 if (name == names._this || name == names._super) return arg; 2237 2238 JCTree.Tag optag = NULLCHK; 2239 JCUnary tree = make.at(arg.pos).Unary(optag, arg); 2240 tree.operator = syms.nullcheck; 2241 tree.type = arg.type; 2242 return tree; 2243 } 2244 2245 public void visitNewArray(JCNewArray tree) { 2246 Type owntype = types.createErrorType(tree.type); 2247 Env<AttrContext> localEnv = env.dup(tree); 2248 Type elemtype; 2249 if (tree.elemtype != null) { 2250 elemtype = attribType(tree.elemtype, localEnv); 2251 chk.validate(tree.elemtype, localEnv); 2252 owntype = elemtype; 2253 for (List<JCExpression> l = tree.dims; l.nonEmpty(); l = l.tail) { 2254 attribExpr(l.head, localEnv, syms.intType); 2255 owntype = new ArrayType(owntype, syms.arrayClass); 2256 } 2257 if (tree.elemtype.hasTag(ANNOTATED_TYPE)) { 2258 checkForDeclarationAnnotations(((JCAnnotatedType) tree.elemtype).annotations, 2259 tree.elemtype.type.tsym); 2260 } 2261 } else { 2262 // we are seeing an untyped aggregate { ... } 2263 // this is allowed only if the prototype is an array 2264 if (pt().hasTag(ARRAY)) { 2265 elemtype = types.elemtype(pt()); 2266 } else { 2267 if (!pt().hasTag(ERROR)) { 2268 log.error(tree.pos(), "illegal.initializer.for.type", 2269 pt()); 2270 } 2271 elemtype = types.createErrorType(pt()); 2272 } 2273 } 2274 if (tree.elems != null) { 2275 attribExprs(tree.elems, localEnv, elemtype); 2276 owntype = new ArrayType(elemtype, syms.arrayClass); 2277 } 2278 if (!types.isReifiable(elemtype)) 2279 log.error(tree.pos(), "generic.array.creation"); 2280 result = check(tree, owntype, VAL, resultInfo); 2281 } 2282 2283 /* 2284 * A lambda expression can only be attributed when a target-type is available. 2285 * In addition, if the target-type is that of a functional interface whose 2286 * descriptor contains inference variables in argument position the lambda expression 2287 * is 'stuck' (see DeferredAttr). 2288 */ 2289 @Override 2290 public void visitLambda(final JCLambda that) { 2291 if (pt().isErroneous() || (pt().hasTag(NONE) && pt() != Type.recoveryType)) { 2292 if (pt().hasTag(NONE)) { 2293 //lambda only allowed in assignment or method invocation/cast context 2294 log.error(that.pos(), "unexpected.lambda"); 2295 } 2296 result = that.type = types.createErrorType(pt()); 2297 return; 2298 } 2299 //create an environment for attribution of the lambda expression 2300 final Env<AttrContext> localEnv = lambdaEnv(that, env); 2301 boolean needsRecovery = 2302 resultInfo.checkContext.deferredAttrContext().mode == DeferredAttr.AttrMode.CHECK; 2303 try { 2304 Type target = pt(); 2305 List<Type> explicitParamTypes = null; 2306 if (that.paramKind == JCLambda.ParameterKind.EXPLICIT) { 2307 //attribute lambda parameters 2308 attribStats(that.params, localEnv); 2309 explicitParamTypes = TreeInfo.types(that.params); 2310 target = infer.instantiateFunctionalInterface(that, target, explicitParamTypes, resultInfo.checkContext); 2311 } 2312 2313 Type lambdaType; 2314 if (pt() != Type.recoveryType) { 2315 target = targetChecker.visit(target, that); 2316 lambdaType = types.findDescriptorType(target); 2317 chk.checkFunctionalInterface(that, target); 2318 } else { 2319 target = Type.recoveryType; 2320 lambdaType = fallbackDescriptorType(that); 2321 } 2322 2323 setFunctionalInfo(that, pt(), lambdaType, target, resultInfo.checkContext.inferenceContext()); 2324 2325 if (lambdaType.hasTag(FORALL)) { 2326 //lambda expression target desc cannot be a generic method 2327 resultInfo.checkContext.report(that, diags.fragment("invalid.generic.lambda.target", 2328 lambdaType, kindName(target.tsym), target.tsym)); 2329 result = that.type = types.createErrorType(pt()); 2330 return; 2331 } 2332 2333 if (that.paramKind == JCLambda.ParameterKind.IMPLICIT) { 2334 //add param type info in the AST 2335 List<Type> actuals = lambdaType.getParameterTypes(); 2336 List<JCVariableDecl> params = that.params; 2337 2338 boolean arityMismatch = false; 2339 2340 while (params.nonEmpty()) { 2341 if (actuals.isEmpty()) { 2342 //not enough actuals to perform lambda parameter inference 2343 arityMismatch = true; 2344 } 2345 //reset previously set info 2346 Type argType = arityMismatch ? 2347 syms.errType : 2348 actuals.head; 2349 params.head.vartype = make.at(params.head).Type(argType); 2350 params.head.sym = null; 2351 actuals = actuals.isEmpty() ? 2352 actuals : 2353 actuals.tail; 2354 params = params.tail; 2355 } 2356 2357 //attribute lambda parameters 2358 attribStats(that.params, localEnv); 2359 2360 if (arityMismatch) { 2361 resultInfo.checkContext.report(that, diags.fragment("incompatible.arg.types.in.lambda")); 2362 result = that.type = types.createErrorType(target); 2363 return; 2364 } 2365 } 2366 2367 //from this point on, no recovery is needed; if we are in assignment context 2368 //we will be able to attribute the whole lambda body, regardless of errors; 2369 //if we are in a 'check' method context, and the lambda is not compatible 2370 //with the target-type, it will be recovered anyway in Attr.checkId 2371 needsRecovery = false; 2372 2373 FunctionalReturnContext funcContext = that.getBodyKind() == JCLambda.BodyKind.EXPRESSION ? 2374 new ExpressionLambdaReturnContext((JCExpression)that.getBody(), resultInfo.checkContext) : 2375 new FunctionalReturnContext(resultInfo.checkContext); 2376 2377 ResultInfo bodyResultInfo = lambdaType.getReturnType() == Type.recoveryType ? 2378 recoveryInfo : 2379 new ResultInfo(VAL, lambdaType.getReturnType(), funcContext); 2380 localEnv.info.returnResult = bodyResultInfo; 2381 2382 Log.DeferredDiagnosticHandler lambdaDeferredHandler = new Log.DeferredDiagnosticHandler(log); 2383 try { 2384 if (that.getBodyKind() == JCLambda.BodyKind.EXPRESSION) { 2385 attribTree(that.getBody(), localEnv, bodyResultInfo); 2386 } else { 2387 JCBlock body = (JCBlock)that.body; 2388 attribStats(body.stats, localEnv); 2389 } 2390 2391 if (resultInfo.checkContext.deferredAttrContext().mode == AttrMode.SPECULATIVE) { 2392 //check for errors in lambda body 2393 for (JCDiagnostic deferredDiag : lambdaDeferredHandler.getDiagnostics()) { 2394 if (deferredDiag.getKind() == JCDiagnostic.Kind.ERROR) { 2395 resultInfo.checkContext 2396 .report(that, diags.fragment("bad.arg.types.in.lambda", TreeInfo.types(that.params), 2397 deferredDiag)); //hidden diag parameter 2398 //we mark the lambda as erroneous - this is crucial in the recovery step 2399 //as parameter-dependent type error won't be reported in that stage, 2400 //meaning that a lambda will be deemed erroeneous only if there is 2401 //a target-independent error (which will cause method diagnostic 2402 //to be skipped). 2403 result = that.type = types.createErrorType(target); 2404 return; 2405 } 2406 } 2407 } 2408 } finally { 2409 lambdaDeferredHandler.reportDeferredDiagnostics(); 2410 log.popDiagnosticHandler(lambdaDeferredHandler); 2411 } 2412 2413 result = check(that, target, VAL, resultInfo); 2414 2415 boolean isSpeculativeRound = 2416 resultInfo.checkContext.deferredAttrContext().mode == DeferredAttr.AttrMode.SPECULATIVE; 2417 2418 postAttr(that); 2419 flow.analyzeLambda(env, that, make, isSpeculativeRound); 2420 2421 checkLambdaCompatible(that, lambdaType, resultInfo.checkContext, isSpeculativeRound); 2422 2423 if (!isSpeculativeRound) { 2424 checkAccessibleTypes(that, localEnv, resultInfo.checkContext.inferenceContext(), lambdaType, target); 2425 } 2426 result = check(that, target, VAL, resultInfo); 2427 } catch (Types.FunctionDescriptorLookupError ex) { 2428 JCDiagnostic cause = ex.getDiagnostic(); 2429 resultInfo.checkContext.report(that, cause); 2430 result = that.type = types.createErrorType(pt()); 2431 return; 2432 } finally { 2433 localEnv.info.scope.leave(); 2434 if (needsRecovery) { 2435 attribTree(that, env, recoveryInfo); 2436 } 2437 } 2438 } 2439 //where 2440 Types.MapVisitor<DiagnosticPosition> targetChecker = new Types.MapVisitor<DiagnosticPosition>() { 2441 2442 @Override 2443 public Type visitClassType(ClassType t, DiagnosticPosition pos) { 2444 return t.isCompound() ? 2445 visitIntersectionClassType((IntersectionClassType)t, pos) : t; 2446 } 2447 2448 public Type visitIntersectionClassType(IntersectionClassType ict, DiagnosticPosition pos) { 2449 Symbol desc = types.findDescriptorSymbol(makeNotionalInterface(ict)); 2450 Type target = null; 2451 for (Type bound : ict.getExplicitComponents()) { 2452 TypeSymbol boundSym = bound.tsym; 2453 if (types.isFunctionalInterface(boundSym) && 2454 types.findDescriptorSymbol(boundSym) == desc) { 2455 target = bound; 2456 } else if (!boundSym.isInterface() || (boundSym.flags() & ANNOTATION) != 0) { 2457 //bound must be an interface 2458 reportIntersectionError(pos, "not.an.intf.component", boundSym); 2459 } 2460 } 2461 return target != null ? 2462 target : 2463 ict.getExplicitComponents().head; //error recovery 2464 } 2465 2466 private TypeSymbol makeNotionalInterface(IntersectionClassType ict) { 2467 ListBuffer<Type> targs = ListBuffer.lb(); 2468 ListBuffer<Type> supertypes = ListBuffer.lb(); 2469 for (Type i : ict.interfaces_field) { 2470 if (i.isParameterized()) { 2471 targs.appendList(i.tsym.type.allparams()); 2472 } 2473 supertypes.append(i.tsym.type); 2474 } 2475 IntersectionClassType notionalIntf = 2476 (IntersectionClassType)types.makeCompoundType(supertypes.toList()); 2477 notionalIntf.allparams_field = targs.toList(); 2478 notionalIntf.tsym.flags_field |= INTERFACE; 2479 return notionalIntf.tsym; 2480 } 2481 2482 private void reportIntersectionError(DiagnosticPosition pos, String key, Object... args) { 2483 resultInfo.checkContext.report(pos, diags.fragment("bad.intersection.target.for.functional.expr", 2484 diags.fragment(key, args))); 2485 } 2486 }; 2487 2488 private Type fallbackDescriptorType(JCExpression tree) { 2489 switch (tree.getTag()) { 2490 case LAMBDA: 2491 JCLambda lambda = (JCLambda)tree; 2492 List<Type> argtypes = List.nil(); 2493 for (JCVariableDecl param : lambda.params) { 2494 argtypes = param.vartype != null ? 2495 argtypes.append(param.vartype.type) : 2496 argtypes.append(syms.errType); 2497 } 2498 return new MethodType(argtypes, Type.recoveryType, 2499 List.of(syms.throwableType), syms.methodClass); 2500 case REFERENCE: 2501 return new MethodType(List.<Type>nil(), Type.recoveryType, 2502 List.of(syms.throwableType), syms.methodClass); 2503 default: 2504 Assert.error("Cannot get here!"); 2505 } 2506 return null; 2507 } 2508 2509 private void checkAccessibleTypes(final DiagnosticPosition pos, final Env<AttrContext> env, 2510 final InferenceContext inferenceContext, final Type... ts) { 2511 checkAccessibleTypes(pos, env, inferenceContext, List.from(ts)); 2512 } 2513 2514 private void checkAccessibleTypes(final DiagnosticPosition pos, final Env<AttrContext> env, 2515 final InferenceContext inferenceContext, final List<Type> ts) { 2516 if (inferenceContext.free(ts)) { 2517 inferenceContext.addFreeTypeListener(ts, new FreeTypeListener() { 2518 @Override 2519 public void typesInferred(InferenceContext inferenceContext) { 2520 checkAccessibleTypes(pos, env, inferenceContext, inferenceContext.asInstTypes(ts)); 2521 } 2522 }); 2523 } else { 2524 for (Type t : ts) { 2525 rs.checkAccessibleType(env, t); 2526 } 2527 } 2528 } 2529 2530 /** 2531 * Lambda/method reference have a special check context that ensures 2532 * that i.e. a lambda return type is compatible with the expected 2533 * type according to both the inherited context and the assignment 2534 * context. 2535 */ 2536 class FunctionalReturnContext extends Check.NestedCheckContext { 2537 2538 FunctionalReturnContext(CheckContext enclosingContext) { 2539 super(enclosingContext); 2540 } 2541 2542 @Override 2543 public boolean compatible(Type found, Type req, Warner warn) { 2544 //return type must be compatible in both current context and assignment context 2545 return chk.basicHandler.compatible(found, inferenceContext().asFree(req), warn); 2546 } 2547 2548 @Override 2549 public void report(DiagnosticPosition pos, JCDiagnostic details) { 2550 enclosingContext.report(pos, diags.fragment("incompatible.ret.type.in.lambda", details)); 2551 } 2552 } 2553 2554 class ExpressionLambdaReturnContext extends FunctionalReturnContext { 2555 2556 JCExpression expr; 2557 2558 ExpressionLambdaReturnContext(JCExpression expr, CheckContext enclosingContext) { 2559 super(enclosingContext); 2560 this.expr = expr; 2561 } 2562 2563 @Override 2564 public boolean compatible(Type found, Type req, Warner warn) { 2565 //a void return is compatible with an expression statement lambda 2566 return TreeInfo.isExpressionStatement(expr) && req.hasTag(VOID) || 2567 super.compatible(found, req, warn); 2568 } 2569 } 2570 2571 /** 2572 * Lambda compatibility. Check that given return types, thrown types, parameter types 2573 * are compatible with the expected functional interface descriptor. This means that: 2574 * (i) parameter types must be identical to those of the target descriptor; (ii) return 2575 * types must be compatible with the return type of the expected descriptor; 2576 * (iii) thrown types must be 'included' in the thrown types list of the expected 2577 * descriptor. 2578 */ 2579 private void checkLambdaCompatible(JCLambda tree, Type descriptor, CheckContext checkContext, boolean speculativeAttr) { 2580 Type returnType = checkContext.inferenceContext().asFree(descriptor.getReturnType()); 2581 2582 //return values have already been checked - but if lambda has no return 2583 //values, we must ensure that void/value compatibility is correct; 2584 //this amounts at checking that, if a lambda body can complete normally, 2585 //the descriptor's return type must be void 2586 if (tree.getBodyKind() == JCLambda.BodyKind.STATEMENT && tree.canCompleteNormally && 2587 !returnType.hasTag(VOID) && returnType != Type.recoveryType) { 2588 checkContext.report(tree, diags.fragment("incompatible.ret.type.in.lambda", 2589 diags.fragment("missing.ret.val", returnType))); 2590 } 2591 2592 List<Type> argTypes = checkContext.inferenceContext().asFree(descriptor.getParameterTypes()); 2593 if (!types.isSameTypes(argTypes, TreeInfo.types(tree.params))) { 2594 checkContext.report(tree, diags.fragment("incompatible.arg.types.in.lambda")); 2595 } 2596 2597 if (!speculativeAttr) { 2598 List<Type> thrownTypes = checkContext.inferenceContext().asFree(descriptor.getThrownTypes()); 2599 if (chk.unhandled(tree.inferredThrownTypes == null ? List.<Type>nil() : tree.inferredThrownTypes, thrownTypes).nonEmpty()) { 2600 log.error(tree, "incompatible.thrown.types.in.lambda", tree.inferredThrownTypes); 2601 } 2602 } 2603 } 2604 2605 private Env<AttrContext> lambdaEnv(JCLambda that, Env<AttrContext> env) { 2606 Env<AttrContext> lambdaEnv; 2607 Symbol owner = env.info.scope.owner; 2608 if (owner.kind == VAR && owner.owner.kind == TYP) { 2609 //field initializer 2610 lambdaEnv = env.dup(that, env.info.dup(env.info.scope.dupUnshared())); 2611 lambdaEnv.info.scope.owner = 2612 new MethodSymbol((owner.flags() & STATIC) | BLOCK, names.empty, null, 2613 env.info.scope.owner); 2614 } else { 2615 lambdaEnv = env.dup(that, env.info.dup(env.info.scope.dup())); 2616 } 2617 return lambdaEnv; 2618 } 2619 2620 @Override 2621 public void visitReference(final JCMemberReference that) { 2622 if (pt().isErroneous() || (pt().hasTag(NONE) && pt() != Type.recoveryType)) { 2623 if (pt().hasTag(NONE)) { 2624 //method reference only allowed in assignment or method invocation/cast context 2625 log.error(that.pos(), "unexpected.mref"); 2626 } 2627 result = that.type = types.createErrorType(pt()); 2628 return; 2629 } 2630 final Env<AttrContext> localEnv = env.dup(that); 2631 try { 2632 //attribute member reference qualifier - if this is a constructor 2633 //reference, the expected kind must be a type 2634 Type exprType = attribTree(that.expr, env, memberReferenceQualifierResult(that)); 2635 2636 if (that.getMode() == JCMemberReference.ReferenceMode.NEW) { 2637 exprType = chk.checkConstructorRefType(that.expr, exprType); 2638 } 2639 2640 if (exprType.isErroneous()) { 2641 //if the qualifier expression contains problems, 2642 //give up attribution of method reference 2643 result = that.type = exprType; 2644 return; 2645 } 2646 2647 if (TreeInfo.isStaticSelector(that.expr, names)) { 2648 //if the qualifier is a type, validate it; raw warning check is 2649 //omitted as we don't know at this stage as to whether this is a 2650 //raw selector (because of inference) 2651 chk.validate(that.expr, env, false); 2652 } 2653 2654 //attrib type-arguments 2655 List<Type> typeargtypes = List.nil(); 2656 if (that.typeargs != null) { 2657 typeargtypes = attribTypes(that.typeargs, localEnv); 2658 } 2659 2660 Type target; 2661 Type desc; 2662 if (pt() != Type.recoveryType) { 2663 target = targetChecker.visit(pt(), that); 2664 desc = types.findDescriptorType(target); 2665 chk.checkFunctionalInterface(that, target); 2666 } else { 2667 target = Type.recoveryType; 2668 desc = fallbackDescriptorType(that); 2669 } 2670 2671 setFunctionalInfo(that, pt(), desc, target, resultInfo.checkContext.inferenceContext()); 2672 List<Type> argtypes = desc.getParameterTypes(); 2673 2674 Pair<Symbol, Resolve.ReferenceLookupHelper> refResult = 2675 rs.resolveMemberReference(that.pos(), localEnv, that, 2676 that.expr.type, that.name, argtypes, typeargtypes, true, rs.resolveMethodCheck); 2677 2678 Symbol refSym = refResult.fst; 2679 Resolve.ReferenceLookupHelper lookupHelper = refResult.snd; 2680 2681 if (refSym.kind != MTH) { 2682 boolean targetError; 2683 switch (refSym.kind) { 2684 case ABSENT_MTH: 2685 targetError = false; 2686 break; 2687 case WRONG_MTH: 2688 case WRONG_MTHS: 2689 case AMBIGUOUS: 2690 case HIDDEN: 2691 case STATICERR: 2692 case MISSING_ENCL: 2693 targetError = true; 2694 break; 2695 default: 2696 Assert.error("unexpected result kind " + refSym.kind); 2697 targetError = false; 2698 } 2699 2700 JCDiagnostic detailsDiag = ((Resolve.ResolveError)refSym).getDiagnostic(JCDiagnostic.DiagnosticType.FRAGMENT, 2701 that, exprType.tsym, exprType, that.name, argtypes, typeargtypes); 2702 2703 JCDiagnostic.DiagnosticType diagKind = targetError ? 2704 JCDiagnostic.DiagnosticType.FRAGMENT : JCDiagnostic.DiagnosticType.ERROR; 2705 2706 JCDiagnostic diag = diags.create(diagKind, log.currentSource(), that, 2707 "invalid.mref", Kinds.kindName(that.getMode()), detailsDiag); 2708 2709 if (targetError && target == Type.recoveryType) { 2710 //a target error doesn't make sense during recovery stage 2711 //as we don't know what actual parameter types are 2712 result = that.type = target; 2713 return; 2714 } else { 2715 if (targetError) { 2716 resultInfo.checkContext.report(that, diag); 2717 } else { 2718 log.report(diag); 2719 } 2720 result = that.type = types.createErrorType(target); 2721 return; 2722 } 2723 } 2724 2725 that.sym = refSym.baseSymbol(); 2726 that.kind = lookupHelper.referenceKind(that.sym); 2727 that.ownerAccessible = rs.isAccessible(localEnv, that.sym.enclClass()); 2728 2729 if (desc.getReturnType() == Type.recoveryType) { 2730 // stop here 2731 result = that.type = target; 2732 return; 2733 } 2734 2735 if (resultInfo.checkContext.deferredAttrContext().mode == AttrMode.CHECK) { 2736 2737 if (that.getMode() == ReferenceMode.INVOKE && 2738 TreeInfo.isStaticSelector(that.expr, names) && 2739 that.kind.isUnbound() && 2740 !desc.getParameterTypes().head.isParameterized()) { 2741 chk.checkRaw(that.expr, localEnv); 2742 } 2743 2744 if (!that.kind.isUnbound() && 2745 that.getMode() == ReferenceMode.INVOKE && 2746 TreeInfo.isStaticSelector(that.expr, names) && 2747 !that.sym.isStatic()) { 2748 log.error(that.expr.pos(), "invalid.mref", Kinds.kindName(that.getMode()), 2749 diags.fragment("non-static.cant.be.ref", Kinds.kindName(refSym), refSym)); 2750 result = that.type = types.createErrorType(target); 2751 return; 2752 } 2753 2754 if (that.kind.isUnbound() && 2755 that.getMode() == ReferenceMode.INVOKE && 2756 TreeInfo.isStaticSelector(that.expr, names) && 2757 that.sym.isStatic()) { 2758 log.error(that.expr.pos(), "invalid.mref", Kinds.kindName(that.getMode()), 2759 diags.fragment("static.method.in.unbound.lookup", Kinds.kindName(refSym), refSym)); 2760 result = that.type = types.createErrorType(target); 2761 return; 2762 } 2763 2764 if (that.sym.isStatic() && TreeInfo.isStaticSelector(that.expr, names) && 2765 exprType.getTypeArguments().nonEmpty()) { 2766 //static ref with class type-args 2767 log.error(that.expr.pos(), "invalid.mref", Kinds.kindName(that.getMode()), 2768 diags.fragment("static.mref.with.targs")); 2769 result = that.type = types.createErrorType(target); 2770 return; 2771 } 2772 2773 if (that.sym.isStatic() && !TreeInfo.isStaticSelector(that.expr, names) && 2774 !that.kind.isUnbound()) { 2775 //no static bound mrefs 2776 log.error(that.expr.pos(), "invalid.mref", Kinds.kindName(that.getMode()), 2777 diags.fragment("static.bound.mref")); 2778 result = that.type = types.createErrorType(target); 2779 return; 2780 } 2781 2782 if (!refSym.isStatic() && that.kind == JCMemberReference.ReferenceKind.SUPER) { 2783 // Check that super-qualified symbols are not abstract (JLS) 2784 rs.checkNonAbstract(that.pos(), that.sym); 2785 } 2786 } 2787 2788 that.sym = refSym.baseSymbol(); 2789 that.kind = lookupHelper.referenceKind(that.sym); 2790 2791 ResultInfo checkInfo = 2792 resultInfo.dup(newMethodTemplate( 2793 desc.getReturnType().hasTag(VOID) ? Type.noType : desc.getReturnType(), 2794 lookupHelper.argtypes, 2795 typeargtypes)); 2796 2797 Type refType = checkId(that, lookupHelper.site, refSym, localEnv, checkInfo); 2798 2799 if (!refType.isErroneous()) { 2800 refType = types.createMethodTypeWithReturn(refType, 2801 adjustMethodReturnType(lookupHelper.site, that.name, checkInfo.pt.getParameterTypes(), refType.getReturnType())); 2802 } 2803 2804 //go ahead with standard method reference compatibility check - note that param check 2805 //is a no-op (as this has been taken care during method applicability) 2806 boolean isSpeculativeRound = 2807 resultInfo.checkContext.deferredAttrContext().mode == DeferredAttr.AttrMode.SPECULATIVE; 2808 checkReferenceCompatible(that, desc, refType, resultInfo.checkContext, isSpeculativeRound); 2809 if (!isSpeculativeRound) { 2810 checkAccessibleTypes(that, localEnv, resultInfo.checkContext.inferenceContext(), desc, target); 2811 } 2812 result = check(that, target, VAL, resultInfo); 2813 } catch (Types.FunctionDescriptorLookupError ex) { 2814 JCDiagnostic cause = ex.getDiagnostic(); 2815 resultInfo.checkContext.report(that, cause); 2816 result = that.type = types.createErrorType(pt()); 2817 return; 2818 } 2819 } 2820 //where 2821 ResultInfo memberReferenceQualifierResult(JCMemberReference tree) { 2822 //if this is a constructor reference, the expected kind must be a type 2823 return new ResultInfo(tree.getMode() == ReferenceMode.INVOKE ? VAL | TYP : TYP, Type.noType); 2824 } 2825 2826 2827 @SuppressWarnings("fallthrough") 2828 void checkReferenceCompatible(JCMemberReference tree, Type descriptor, Type refType, CheckContext checkContext, boolean speculativeAttr) { 2829 Type returnType = checkContext.inferenceContext().asFree(descriptor.getReturnType()); 2830 2831 Type resType; 2832 switch (tree.getMode()) { 2833 case NEW: 2834 if (!tree.expr.type.isRaw()) { 2835 resType = tree.expr.type; 2836 break; 2837 } 2838 default: 2839 resType = refType.getReturnType(); 2840 } 2841 2842 Type incompatibleReturnType = resType; 2843 2844 if (returnType.hasTag(VOID)) { 2845 incompatibleReturnType = null; 2846 } 2847 2848 if (!returnType.hasTag(VOID) && !resType.hasTag(VOID)) { 2849 if (resType.isErroneous() || 2850 new FunctionalReturnContext(checkContext).compatible(resType, returnType, types.noWarnings)) { 2851 incompatibleReturnType = null; 2852 } 2853 } 2854 2855 if (incompatibleReturnType != null) { 2856 checkContext.report(tree, diags.fragment("incompatible.ret.type.in.mref", 2857 diags.fragment("inconvertible.types", resType, descriptor.getReturnType()))); 2858 } 2859 2860 if (!speculativeAttr) { 2861 List<Type> thrownTypes = checkContext.inferenceContext().asFree(descriptor.getThrownTypes()); 2862 if (chk.unhandled(refType.getThrownTypes(), thrownTypes).nonEmpty()) { 2863 log.error(tree, "incompatible.thrown.types.in.mref", refType.getThrownTypes()); 2864 } 2865 } 2866 } 2867 2868 /** 2869 * Set functional type info on the underlying AST. Note: as the target descriptor 2870 * might contain inference variables, we might need to register an hook in the 2871 * current inference context. 2872 */ 2873 private void setFunctionalInfo(final JCFunctionalExpression fExpr, final Type pt, 2874 final Type descriptorType, final Type primaryTarget, InferenceContext inferenceContext) { 2875 if (inferenceContext.free(descriptorType)) { 2876 inferenceContext.addFreeTypeListener(List.of(pt, descriptorType), new FreeTypeListener() { 2877 public void typesInferred(InferenceContext inferenceContext) { 2878 setFunctionalInfo(fExpr, pt, inferenceContext.asInstType(descriptorType), 2879 inferenceContext.asInstType(primaryTarget), inferenceContext); 2880 } 2881 }); 2882 } else { 2883 ListBuffer<TypeSymbol> targets = ListBuffer.lb(); 2884 if (pt.hasTag(CLASS)) { 2885 if (pt.isCompound()) { 2886 targets.append(primaryTarget.tsym); //this goes first 2887 for (Type t : ((IntersectionClassType)pt()).interfaces_field) { 2888 if (t != primaryTarget) { 2889 targets.append(t.tsym); 2890 } 2891 } 2892 } else { 2893 targets.append(pt.tsym); 2894 } 2895 } 2896 fExpr.targets = targets.toList(); 2897 fExpr.descriptorType = descriptorType; 2898 } 2899 } 2900 2901 public void visitParens(JCParens tree) { 2902 Type owntype = attribTree(tree.expr, env, resultInfo); 2903 result = check(tree, owntype, pkind(), resultInfo); 2904 Symbol sym = TreeInfo.symbol(tree); 2905 if (sym != null && (sym.kind&(TYP|PCK)) != 0) 2906 log.error(tree.pos(), "illegal.start.of.type"); 2907 } 2908 2909 public void visitAssign(JCAssign tree) { 2910 Type owntype = attribTree(tree.lhs, env.dup(tree), varInfo); 2911 Type capturedType = capture(owntype); 2912 attribExpr(tree.rhs, env, owntype); 2913 result = check(tree, capturedType, VAL, resultInfo); 2914 } 2915 2916 public void visitAssignop(JCAssignOp tree) { 2917 // Attribute arguments. 2918 Type owntype = attribTree(tree.lhs, env, varInfo); 2919 Type operand = attribExpr(tree.rhs, env); 2920 // Find operator. 2921 Symbol operator = tree.operator = rs.resolveBinaryOperator( 2922 tree.pos(), tree.getTag().noAssignOp(), env, 2923 owntype, operand); 2924 2925 if (operator.kind == MTH && 2926 !owntype.isErroneous() && 2927 !operand.isErroneous()) { 2928 chk.checkOperator(tree.pos(), 2929 (OperatorSymbol)operator, 2930 tree.getTag().noAssignOp(), 2931 owntype, 2932 operand); 2933 chk.checkDivZero(tree.rhs.pos(), operator, operand); 2934 chk.checkCastable(tree.rhs.pos(), 2935 operator.type.getReturnType(), 2936 owntype); 2937 } 2938 result = check(tree, owntype, VAL, resultInfo); 2939 } 2940 2941 public void visitUnary(JCUnary tree) { 2942 // Attribute arguments. 2943 Type argtype = (tree.getTag().isIncOrDecUnaryOp()) 2944 ? attribTree(tree.arg, env, varInfo) 2945 : chk.checkNonVoid(tree.arg.pos(), attribExpr(tree.arg, env)); 2946 2947 // Find operator. 2948 Symbol operator = tree.operator = 2949 rs.resolveUnaryOperator(tree.pos(), tree.getTag(), env, argtype); 2950 2951 Type owntype = types.createErrorType(tree.type); 2952 if (operator.kind == MTH && 2953 !argtype.isErroneous()) { 2954 owntype = (tree.getTag().isIncOrDecUnaryOp()) 2955 ? tree.arg.type 2956 : operator.type.getReturnType(); 2957 int opc = ((OperatorSymbol)operator).opcode; 2958 2959 // If the argument is constant, fold it. 2960 if (argtype.constValue() != null) { 2961 Type ctype = cfolder.fold1(opc, argtype); 2962 if (ctype != null) { 2963 owntype = cfolder.coerce(ctype, owntype); 2964 2965 // Remove constant types from arguments to 2966 // conserve space. The parser will fold concatenations 2967 // of string literals; the code here also 2968 // gets rid of intermediate results when some of the 2969 // operands are constant identifiers. 2970 if (tree.arg.type.tsym == syms.stringType.tsym) { 2971 tree.arg.type = syms.stringType; 2972 } 2973 } 2974 } 2975 } 2976 result = check(tree, owntype, VAL, resultInfo); 2977 } 2978 2979 public void visitBinary(JCBinary tree) { 2980 // Attribute arguments. 2981 Type left = chk.checkNonVoid(tree.lhs.pos(), attribExpr(tree.lhs, env)); 2982 Type right = chk.checkNonVoid(tree.lhs.pos(), attribExpr(tree.rhs, env)); 2983 2984 // Find operator. 2985 Symbol operator = tree.operator = 2986 rs.resolveBinaryOperator(tree.pos(), tree.getTag(), env, left, right); 2987 2988 Type owntype = types.createErrorType(tree.type); 2989 if (operator.kind == MTH && 2990 !left.isErroneous() && 2991 !right.isErroneous()) { 2992 owntype = operator.type.getReturnType(); 2993 int opc = chk.checkOperator(tree.lhs.pos(), 2994 (OperatorSymbol)operator, 2995 tree.getTag(), 2996 left, 2997 right); 2998 2999 // If both arguments are constants, fold them. 3000 if (left.constValue() != null && right.constValue() != null) { 3001 Type ctype = cfolder.fold2(opc, left, right); 3002 if (ctype != null) { 3003 owntype = cfolder.coerce(ctype, owntype); 3004 3005 // Remove constant types from arguments to 3006 // conserve space. The parser will fold concatenations 3007 // of string literals; the code here also 3008 // gets rid of intermediate results when some of the 3009 // operands are constant identifiers. 3010 if (tree.lhs.type.tsym == syms.stringType.tsym) { 3011 tree.lhs.type = syms.stringType; 3012 } 3013 if (tree.rhs.type.tsym == syms.stringType.tsym) { 3014 tree.rhs.type = syms.stringType; 3015 } 3016 } 3017 } 3018 3019 // Check that argument types of a reference ==, != are 3020 // castable to each other, (JLS???). 3021 if ((opc == ByteCodes.if_acmpeq || opc == ByteCodes.if_acmpne)) { 3022 if (!types.isCastable(left, right, new Warner(tree.pos()))) { 3023 log.error(tree.pos(), "incomparable.types", left, right); 3024 } 3025 } 3026 3027 chk.checkDivZero(tree.rhs.pos(), operator, right); 3028 } 3029 result = check(tree, owntype, VAL, resultInfo); 3030 } 3031 3032 public void visitTypeCast(final JCTypeCast tree) { 3033 Type clazztype = attribType(tree.clazz, env); 3034 chk.validate(tree.clazz, env, false); 3035 //a fresh environment is required for 292 inference to work properly --- 3036 //see Infer.instantiatePolymorphicSignatureInstance() 3037 Env<AttrContext> localEnv = env.dup(tree); 3038 //should we propagate the target type? 3039 final ResultInfo castInfo; 3040 JCExpression expr = TreeInfo.skipParens(tree.expr); 3041 boolean isPoly = expr.hasTag(LAMBDA) || expr.hasTag(REFERENCE); 3042 if (isPoly) { 3043 //expression is a poly - we need to propagate target type info 3044 castInfo = new ResultInfo(VAL, clazztype, new Check.NestedCheckContext(resultInfo.checkContext) { 3045 @Override 3046 public boolean compatible(Type found, Type req, Warner warn) { 3047 return types.isCastable(found, req, warn); 3048 } 3049 }); 3050 } else { 3051 //standalone cast - target-type info is not propagated 3052 castInfo = unknownExprInfo; 3053 } 3054 Type exprtype = attribTree(tree.expr, localEnv, castInfo); 3055 Type owntype = isPoly ? clazztype : chk.checkCastable(tree.expr.pos(), exprtype, clazztype); 3056 if (exprtype.constValue() != null) 3057 owntype = cfolder.coerce(exprtype, owntype); 3058 result = check(tree, capture(owntype), VAL, resultInfo); 3059 if (!isPoly) 3060 chk.checkRedundantCast(localEnv, tree); 3061 } 3062 3063 public void visitTypeTest(JCInstanceOf tree) { 3064 Type exprtype = chk.checkNullOrRefType( 3065 tree.expr.pos(), attribExpr(tree.expr, env)); 3066 Type clazztype = chk.checkReifiableReferenceType( 3067 tree.clazz.pos(), attribType(tree.clazz, env)); 3068 chk.validate(tree.clazz, env, false); 3069 chk.checkCastable(tree.expr.pos(), exprtype, clazztype); 3070 result = check(tree, syms.booleanType, VAL, resultInfo); 3071 } 3072 3073 public void visitIndexed(JCArrayAccess tree) { 3074 Type owntype = types.createErrorType(tree.type); 3075 Type atype = attribExpr(tree.indexed, env); 3076 attribExpr(tree.index, env, syms.intType); 3077 if (types.isArray(atype)) 3078 owntype = types.elemtype(atype); 3079 else if (!atype.hasTag(ERROR)) 3080 log.error(tree.pos(), "array.req.but.found", atype); 3081 if ((pkind() & VAR) == 0) owntype = capture(owntype); 3082 result = check(tree, owntype, VAR, resultInfo); 3083 } 3084 3085 public void visitIdent(JCIdent tree) { 3086 Symbol sym; 3087 3088 // Find symbol 3089 if (pt().hasTag(METHOD) || pt().hasTag(FORALL)) { 3090 // If we are looking for a method, the prototype `pt' will be a 3091 // method type with the type of the call's arguments as parameters. 3092 env.info.pendingResolutionPhase = null; 3093 sym = rs.resolveMethod(tree.pos(), env, tree.name, pt().getParameterTypes(), pt().getTypeArguments()); 3094 } else if (tree.sym != null && tree.sym.kind != VAR) { 3095 sym = tree.sym; 3096 } else { 3097 sym = rs.resolveIdent(tree.pos(), env, tree.name, pkind()); 3098 } 3099 tree.sym = sym; 3100 3101 // (1) Also find the environment current for the class where 3102 // sym is defined (`symEnv'). 3103 // Only for pre-tiger versions (1.4 and earlier): 3104 // (2) Also determine whether we access symbol out of an anonymous 3105 // class in a this or super call. This is illegal for instance 3106 // members since such classes don't carry a this$n link. 3107 // (`noOuterThisPath'). 3108 Env<AttrContext> symEnv = env; 3109 boolean noOuterThisPath = false; 3110 if (env.enclClass.sym.owner.kind != PCK && // we are in an inner class 3111 (sym.kind & (VAR | MTH | TYP)) != 0 && 3112 sym.owner.kind == TYP && 3113 tree.name != names._this && tree.name != names._super) { 3114 3115 // Find environment in which identifier is defined. 3116 while (symEnv.outer != null && 3117 !sym.isMemberOf(symEnv.enclClass.sym, types)) { 3118 if ((symEnv.enclClass.sym.flags() & NOOUTERTHIS) != 0) 3119 noOuterThisPath = !allowAnonOuterThis; 3120 symEnv = symEnv.outer; 3121 } 3122 } 3123 3124 // If symbol is a variable, ... 3125 if (sym.kind == VAR) { 3126 VarSymbol v = (VarSymbol)sym; 3127 3128 // ..., evaluate its initializer, if it has one, and check for 3129 // illegal forward reference. 3130 checkInit(tree, env, v, false); 3131 3132 // If we are expecting a variable (as opposed to a value), check 3133 // that the variable is assignable in the current environment. 3134 if (pkind() == VAR) 3135 checkAssignable(tree.pos(), v, null, env); 3136 } 3137 3138 // In a constructor body, 3139 // if symbol is a field or instance method, check that it is 3140 // not accessed before the supertype constructor is called. 3141 if ((symEnv.info.isSelfCall || noOuterThisPath) && 3142 (sym.kind & (VAR | MTH)) != 0 && 3143 sym.owner.kind == TYP && 3144 (sym.flags() & STATIC) == 0) { 3145 chk.earlyRefError(tree.pos(), sym.kind == VAR ? sym : thisSym(tree.pos(), env)); 3146 } 3147 Env<AttrContext> env1 = env; 3148 if (sym.kind != ERR && sym.kind != TYP && sym.owner != null && sym.owner != env1.enclClass.sym) { 3149 // If the found symbol is inaccessible, then it is 3150 // accessed through an enclosing instance. Locate this 3151 // enclosing instance: 3152 while (env1.outer != null && !rs.isAccessible(env, env1.enclClass.sym.type, sym)) 3153 env1 = env1.outer; 3154 } 3155 result = checkId(tree, env1.enclClass.sym.type, sym, env, resultInfo); 3156 } 3157 3158 public void visitSelect(JCFieldAccess tree) { 3159 // Determine the expected kind of the qualifier expression. 3160 int skind = 0; 3161 if (tree.name == names._this || tree.name == names._super || 3162 tree.name == names._class) 3163 { 3164 skind = TYP; 3165 } else { 3166 if ((pkind() & PCK) != 0) skind = skind | PCK; 3167 if ((pkind() & TYP) != 0) skind = skind | TYP | PCK; 3168 if ((pkind() & (VAL | MTH)) != 0) skind = skind | VAL | TYP; 3169 } 3170 3171 // Attribute the qualifier expression, and determine its symbol (if any). 3172 Type site = attribTree(tree.selected, env, new ResultInfo(skind, Infer.anyPoly)); 3173 if ((pkind() & (PCK | TYP)) == 0) 3174 site = capture(site); // Capture field access 3175 3176 // don't allow T.class T[].class, etc 3177 if (skind == TYP) { 3178 Type elt = site; 3179 while (elt.hasTag(ARRAY)) 3180 elt = ((ArrayType)elt).elemtype; 3181 if (elt.hasTag(TYPEVAR)) { 3182 log.error(tree.pos(), "type.var.cant.be.deref"); 3183 result = types.createErrorType(tree.type); 3184 return; 3185 } 3186 } 3187 3188 // If qualifier symbol is a type or `super', assert `selectSuper' 3189 // for the selection. This is relevant for determining whether 3190 // protected symbols are accessible. 3191 Symbol sitesym = TreeInfo.symbol(tree.selected); 3192 boolean selectSuperPrev = env.info.selectSuper; 3193 env.info.selectSuper = 3194 sitesym != null && 3195 sitesym.name == names._super; 3196 3197 // Determine the symbol represented by the selection. 3198 env.info.pendingResolutionPhase = null; 3199 Symbol sym = selectSym(tree, sitesym, site, env, resultInfo); 3200 if (sym.exists() && !isType(sym) && (pkind() & (PCK | TYP)) != 0) { 3201 site = capture(site); 3202 sym = selectSym(tree, sitesym, site, env, resultInfo); 3203 } 3204 boolean varArgs = env.info.lastResolveVarargs(); 3205 tree.sym = sym; 3206 3207 if (site.hasTag(TYPEVAR) && !isType(sym) && sym.kind != ERR) { 3208 while (site.hasTag(TYPEVAR)) site = site.getUpperBound(); 3209 site = capture(site); 3210 } 3211 3212 // If that symbol is a variable, ... 3213 if (sym.kind == VAR) { 3214 VarSymbol v = (VarSymbol)sym; 3215 3216 // ..., evaluate its initializer, if it has one, and check for 3217 // illegal forward reference. 3218 checkInit(tree, env, v, true); 3219 3220 // If we are expecting a variable (as opposed to a value), check 3221 // that the variable is assignable in the current environment. 3222 if (pkind() == VAR) 3223 checkAssignable(tree.pos(), v, tree.selected, env); 3224 } 3225 3226 if (sitesym != null && 3227 sitesym.kind == VAR && 3228 ((VarSymbol)sitesym).isResourceVariable() && 3229 sym.kind == MTH && 3230 sym.name.equals(names.close) && 3231 sym.overrides(syms.autoCloseableClose, sitesym.type.tsym, types, true) && 3232 env.info.lint.isEnabled(LintCategory.TRY)) { 3233 log.warning(LintCategory.TRY, tree, "try.explicit.close.call"); 3234 } 3235 3236 // Disallow selecting a type from an expression 3237 if (isType(sym) && (sitesym==null || (sitesym.kind&(TYP|PCK)) == 0)) { 3238 tree.type = check(tree.selected, pt(), 3239 sitesym == null ? VAL : sitesym.kind, new ResultInfo(TYP|PCK, pt())); 3240 } 3241 3242 if (isType(sitesym)) { 3243 if (sym.name == names._this) { 3244 // If `C' is the currently compiled class, check that 3245 // C.this' does not appear in a call to a super(...) 3246 if (env.info.isSelfCall && 3247 site.tsym == env.enclClass.sym) { 3248 chk.earlyRefError(tree.pos(), sym); 3249 } 3250 } else { 3251 // Check if type-qualified fields or methods are static (JLS) 3252 if ((sym.flags() & STATIC) == 0 && 3253 !env.next.tree.hasTag(REFERENCE) && 3254 sym.name != names._super && 3255 (sym.kind == VAR || sym.kind == MTH)) { 3256 rs.accessBase(rs.new StaticError(sym), 3257 tree.pos(), site, sym.name, true); 3258 } 3259 } 3260 } else if (sym.kind != ERR && (sym.flags() & STATIC) != 0 && sym.name != names._class) { 3261 // If the qualified item is not a type and the selected item is static, report 3262 // a warning. Make allowance for the class of an array type e.g. Object[].class) 3263 chk.warnStatic(tree, "static.not.qualified.by.type", Kinds.kindName(sym.kind), sym.owner); 3264 } 3265 3266 // If we are selecting an instance member via a `super', ... 3267 if (env.info.selectSuper && (sym.flags() & STATIC) == 0) { 3268 3269 // Check that super-qualified symbols are not abstract (JLS) 3270 rs.checkNonAbstract(tree.pos(), sym); 3271 3272 if (site.isRaw()) { 3273 // Determine argument types for site. 3274 Type site1 = types.asSuper(env.enclClass.sym.type, site.tsym); 3275 if (site1 != null) site = site1; 3276 } 3277 } 3278 3279 env.info.selectSuper = selectSuperPrev; 3280 result = checkId(tree, site, sym, env, resultInfo); 3281 } 3282 //where 3283 /** Determine symbol referenced by a Select expression, 3284 * 3285 * @param tree The select tree. 3286 * @param site The type of the selected expression, 3287 * @param env The current environment. 3288 * @param resultInfo The current result. 3289 */ 3290 private Symbol selectSym(JCFieldAccess tree, 3291 Symbol location, 3292 Type site, 3293 Env<AttrContext> env, 3294 ResultInfo resultInfo) { 3295 DiagnosticPosition pos = tree.pos(); 3296 Name name = tree.name; 3297 switch (site.getTag()) { 3298 case PACKAGE: 3299 return rs.accessBase( 3300 rs.findIdentInPackage(env, site.tsym, name, resultInfo.pkind), 3301 pos, location, site, name, true); 3302 case ARRAY: 3303 case CLASS: 3304 if (resultInfo.pt.hasTag(METHOD) || resultInfo.pt.hasTag(FORALL)) { 3305 return rs.resolveQualifiedMethod( 3306 pos, env, location, site, name, resultInfo.pt.getParameterTypes(), resultInfo.pt.getTypeArguments()); 3307 } else if (name == names._this || name == names._super) { 3308 return rs.resolveSelf(pos, env, site.tsym, name); 3309 } else if (name == names._class) { 3310 // In this case, we have already made sure in 3311 // visitSelect that qualifier expression is a type. 3312 Type t = syms.classType; 3313 List<Type> typeargs = allowGenerics 3314 ? List.of(types.erasure(site)) 3315 : List.<Type>nil(); 3316 t = new ClassType(t.getEnclosingType(), typeargs, t.tsym); 3317 return new VarSymbol( 3318 STATIC | PUBLIC | FINAL, names._class, t, site.tsym); 3319 } else { 3320 // We are seeing a plain identifier as selector. 3321 Symbol sym = rs.findIdentInType(env, site, name, resultInfo.pkind); 3322 if ((resultInfo.pkind & ERRONEOUS) == 0) 3323 sym = rs.accessBase(sym, pos, location, site, name, true); 3324 return sym; 3325 } 3326 case WILDCARD: 3327 throw new AssertionError(tree); 3328 case TYPEVAR: 3329 // Normally, site.getUpperBound() shouldn't be null. 3330 // It should only happen during memberEnter/attribBase 3331 // when determining the super type which *must* beac 3332 // done before attributing the type variables. In 3333 // other words, we are seeing this illegal program: 3334 // class B<T> extends A<T.foo> {} 3335 Symbol sym = (site.getUpperBound() != null) 3336 ? selectSym(tree, location, capture(site.getUpperBound()), env, resultInfo) 3337 : null; 3338 if (sym == null) { 3339 log.error(pos, "type.var.cant.be.deref"); 3340 return syms.errSymbol; 3341 } else { 3342 Symbol sym2 = (sym.flags() & Flags.PRIVATE) != 0 ? 3343 rs.new AccessError(env, site, sym) : 3344 sym; 3345 rs.accessBase(sym2, pos, location, site, name, true); 3346 return sym; 3347 } 3348 case ERROR: 3349 // preserve identifier names through errors 3350 return types.createErrorType(name, site.tsym, site).tsym; 3351 default: 3352 // The qualifier expression is of a primitive type -- only 3353 // .class is allowed for these. 3354 if (name == names._class) { 3355 // In this case, we have already made sure in Select that 3356 // qualifier expression is a type. 3357 Type t = syms.classType; 3358 Type arg = types.boxedClass(site).type; 3359 t = new ClassType(t.getEnclosingType(), List.of(arg), t.tsym); 3360 return new VarSymbol( 3361 STATIC | PUBLIC | FINAL, names._class, t, site.tsym); 3362 } else { 3363 log.error(pos, "cant.deref", site); 3364 return syms.errSymbol; 3365 } 3366 } 3367 } 3368 3369 /** Determine type of identifier or select expression and check that 3370 * (1) the referenced symbol is not deprecated 3371 * (2) the symbol's type is safe (@see checkSafe) 3372 * (3) if symbol is a variable, check that its type and kind are 3373 * compatible with the prototype and protokind. 3374 * (4) if symbol is an instance field of a raw type, 3375 * which is being assigned to, issue an unchecked warning if its 3376 * type changes under erasure. 3377 * (5) if symbol is an instance method of a raw type, issue an 3378 * unchecked warning if its argument types change under erasure. 3379 * If checks succeed: 3380 * If symbol is a constant, return its constant type 3381 * else if symbol is a method, return its result type 3382 * otherwise return its type. 3383 * Otherwise return errType. 3384 * 3385 * @param tree The syntax tree representing the identifier 3386 * @param site If this is a select, the type of the selected 3387 * expression, otherwise the type of the current class. 3388 * @param sym The symbol representing the identifier. 3389 * @param env The current environment. 3390 * @param resultInfo The expected result 3391 */ 3392 Type checkId(JCTree tree, 3393 Type site, 3394 Symbol sym, 3395 Env<AttrContext> env, 3396 ResultInfo resultInfo) { 3397 return (resultInfo.pt.hasTag(FORALL) || resultInfo.pt.hasTag(METHOD)) ? 3398 checkMethodId(tree, site, sym, env, resultInfo) : 3399 checkIdInternal(tree, site, sym, resultInfo.pt, env, resultInfo); 3400 } 3401 3402 Type checkMethodId(JCTree tree, 3403 Type site, 3404 Symbol sym, 3405 Env<AttrContext> env, 3406 ResultInfo resultInfo) { 3407 boolean isPolymorhicSignature = 3408 sym.kind == MTH && ((MethodSymbol)sym.baseSymbol()).isSignaturePolymorphic(types); 3409 return isPolymorhicSignature ? 3410 checkSigPolyMethodId(tree, site, sym, env, resultInfo) : 3411 checkMethodIdInternal(tree, site, sym, env, resultInfo); 3412 } 3413 3414 Type checkSigPolyMethodId(JCTree tree, 3415 Type site, 3416 Symbol sym, 3417 Env<AttrContext> env, 3418 ResultInfo resultInfo) { 3419 //recover original symbol for signature polymorphic methods 3420 checkMethodIdInternal(tree, site, sym.baseSymbol(), env, resultInfo); 3421 env.info.pendingResolutionPhase = Resolve.MethodResolutionPhase.BASIC; 3422 return sym.type; 3423 } 3424 3425 Type checkMethodIdInternal(JCTree tree, 3426 Type site, 3427 Symbol sym, 3428 Env<AttrContext> env, 3429 ResultInfo resultInfo) { 3430 Type pt = resultInfo.pt.map(deferredAttr.new RecoveryDeferredTypeMap(AttrMode.SPECULATIVE, sym, env.info.pendingResolutionPhase)); 3431 Type owntype = checkIdInternal(tree, site, sym, pt, env, resultInfo); 3432 resultInfo.pt.map(deferredAttr.new RecoveryDeferredTypeMap(AttrMode.CHECK, sym, env.info.pendingResolutionPhase)); 3433 return owntype; 3434 } 3435 3436 Type checkIdInternal(JCTree tree, 3437 Type site, 3438 Symbol sym, 3439 Type pt, 3440 Env<AttrContext> env, 3441 ResultInfo resultInfo) { 3442 if (pt.isErroneous()) { 3443 return types.createErrorType(site); 3444 } 3445 Type owntype; // The computed type of this identifier occurrence. 3446 switch (sym.kind) { 3447 case TYP: 3448 // For types, the computed type equals the symbol's type, 3449 // except for two situations: 3450 owntype = sym.type; 3451 if (owntype.hasTag(CLASS)) { 3452 chk.checkForBadAuxiliaryClassAccess(tree.pos(), env, (ClassSymbol)sym); 3453 Type ownOuter = owntype.getEnclosingType(); 3454 3455 // (a) If the symbol's type is parameterized, erase it 3456 // because no type parameters were given. 3457 // We recover generic outer type later in visitTypeApply. 3458 if (owntype.tsym.type.getTypeArguments().nonEmpty()) { 3459 owntype = types.erasure(owntype); 3460 } 3461 3462 // (b) If the symbol's type is an inner class, then 3463 // we have to interpret its outer type as a superclass 3464 // of the site type. Example: 3465 // 3466 // class Tree<A> { class Visitor { ... } } 3467 // class PointTree extends Tree<Point> { ... } 3468 // ...PointTree.Visitor... 3469 // 3470 // Then the type of the last expression above is 3471 // Tree<Point>.Visitor. 3472 else if (ownOuter.hasTag(CLASS) && site != ownOuter) { 3473 Type normOuter = site; 3474 if (normOuter.hasTag(CLASS)) { 3475 normOuter = types.asEnclosingSuper(site, ownOuter.tsym); 3476 if (site.isAnnotated()) { 3477 // Propagate any type annotations. 3478 // TODO: should asEnclosingSuper do this? 3479 // Note that the type annotations in site will be updated 3480 // by annotateType. Therefore, modify site instead 3481 // of creating a new AnnotatedType. 3482 ((AnnotatedType)site).underlyingType = normOuter; 3483 normOuter = site; 3484 } 3485 } 3486 if (normOuter == null) // perhaps from an import 3487 normOuter = types.erasure(ownOuter); 3488 if (normOuter != ownOuter) 3489 owntype = new ClassType( 3490 normOuter, List.<Type>nil(), owntype.tsym); 3491 } 3492 } 3493 break; 3494 case VAR: 3495 VarSymbol v = (VarSymbol)sym; 3496 // Test (4): if symbol is an instance field of a raw type, 3497 // which is being assigned to, issue an unchecked warning if 3498 // its type changes under erasure. 3499 if (allowGenerics && 3500 resultInfo.pkind == VAR && 3501 v.owner.kind == TYP && 3502 (v.flags() & STATIC) == 0 && 3503 (site.hasTag(CLASS) || site.hasTag(TYPEVAR))) { 3504 Type s = types.asOuterSuper(site, v.owner); 3505 if (s != null && 3506 s.isRaw() && 3507 !types.isSameType(v.type, v.erasure(types))) { 3508 chk.warnUnchecked(tree.pos(), 3509 "unchecked.assign.to.var", 3510 v, s); 3511 } 3512 } 3513 // The computed type of a variable is the type of the 3514 // variable symbol, taken as a member of the site type. 3515 owntype = (sym.owner.kind == TYP && 3516 sym.name != names._this && sym.name != names._super) 3517 ? types.memberType(site, sym) 3518 : sym.type; 3519 3520 // If the variable is a constant, record constant value in 3521 // computed type. 3522 if (v.getConstValue() != null && isStaticReference(tree)) 3523 owntype = owntype.constType(v.getConstValue()); 3524 3525 if (resultInfo.pkind == VAL) { 3526 owntype = capture(owntype); // capture "names as expressions" 3527 } 3528 break; 3529 case MTH: { 3530 owntype = checkMethod(site, sym, 3531 new ResultInfo(VAL, resultInfo.pt.getReturnType(), resultInfo.checkContext), 3532 env, TreeInfo.args(env.tree), resultInfo.pt.getParameterTypes(), 3533 resultInfo.pt.getTypeArguments()); 3534 break; 3535 } 3536 case PCK: case ERR: 3537 owntype = sym.type; 3538 break; 3539 default: 3540 throw new AssertionError("unexpected kind: " + sym.kind + 3541 " in tree " + tree); 3542 } 3543 3544 // Test (1): emit a `deprecation' warning if symbol is deprecated. 3545 // (for constructors, the error was given when the constructor was 3546 // resolved) 3547 3548 if (sym.name != names.init) { 3549 chk.checkDeprecated(tree.pos(), env.info.scope.owner, sym); 3550 chk.checkSunAPI(tree.pos(), sym); 3551 chk.checkProfile(tree.pos(), sym); 3552 } 3553 3554 // Test (3): if symbol is a variable, check that its type and 3555 // kind are compatible with the prototype and protokind. 3556 return check(tree, owntype, sym.kind, resultInfo); 3557 } 3558 3559 /** Check that variable is initialized and evaluate the variable's 3560 * initializer, if not yet done. Also check that variable is not 3561 * referenced before it is defined. 3562 * @param tree The tree making up the variable reference. 3563 * @param env The current environment. 3564 * @param v The variable's symbol. 3565 */ 3566 private void checkInit(JCTree tree, 3567 Env<AttrContext> env, 3568 VarSymbol v, 3569 boolean onlyWarning) { 3570 // System.err.println(v + " " + ((v.flags() & STATIC) != 0) + " " + 3571 // tree.pos + " " + v.pos + " " + 3572 // Resolve.isStatic(env));//DEBUG 3573 3574 // A forward reference is diagnosed if the declaration position 3575 // of the variable is greater than the current tree position 3576 // and the tree and variable definition occur in the same class 3577 // definition. Note that writes don't count as references. 3578 // This check applies only to class and instance 3579 // variables. Local variables follow different scope rules, 3580 // and are subject to definite assignment checking. 3581 if ((env.info.enclVar == v || v.pos > tree.pos) && 3582 v.owner.kind == TYP && 3583 canOwnInitializer(owner(env)) && 3584 v.owner == env.info.scope.owner.enclClass() && 3585 ((v.flags() & STATIC) != 0) == Resolve.isStatic(env) && 3586 (!env.tree.hasTag(ASSIGN) || 3587 TreeInfo.skipParens(((JCAssign) env.tree).lhs) != tree)) { 3588 String suffix = (env.info.enclVar == v) ? 3589 "self.ref" : "forward.ref"; 3590 if (!onlyWarning || isStaticEnumField(v)) { 3591 log.error(tree.pos(), "illegal." + suffix); 3592 } else if (useBeforeDeclarationWarning) { 3593 log.warning(tree.pos(), suffix, v); 3594 } 3595 } 3596 3597 v.getConstValue(); // ensure initializer is evaluated 3598 3599 checkEnumInitializer(tree, env, v); 3600 } 3601 3602 /** 3603 * Check for illegal references to static members of enum. In 3604 * an enum type, constructors and initializers may not 3605 * reference its static members unless they are constant. 3606 * 3607 * @param tree The tree making up the variable reference. 3608 * @param env The current environment. 3609 * @param v The variable's symbol. 3610 * @jls section 8.9 Enums 3611 */ 3612 private void checkEnumInitializer(JCTree tree, Env<AttrContext> env, VarSymbol v) { 3613 // JLS: 3614 // 3615 // "It is a compile-time error to reference a static field 3616 // of an enum type that is not a compile-time constant 3617 // (15.28) from constructors, instance initializer blocks, 3618 // or instance variable initializer expressions of that 3619 // type. It is a compile-time error for the constructors, 3620 // instance initializer blocks, or instance variable 3621 // initializer expressions of an enum constant e to refer 3622 // to itself or to an enum constant of the same type that 3623 // is declared to the right of e." 3624 if (isStaticEnumField(v)) { 3625 ClassSymbol enclClass = env.info.scope.owner.enclClass(); 3626 3627 if (enclClass == null || enclClass.owner == null) 3628 return; 3629 3630 // See if the enclosing class is the enum (or a 3631 // subclass thereof) declaring v. If not, this 3632 // reference is OK. 3633 if (v.owner != enclClass && !types.isSubtype(enclClass.type, v.owner.type)) 3634 return; 3635 3636 // If the reference isn't from an initializer, then 3637 // the reference is OK. 3638 if (!Resolve.isInitializer(env)) 3639 return; 3640 3641 log.error(tree.pos(), "illegal.enum.static.ref"); 3642 } 3643 } 3644 3645 /** Is the given symbol a static, non-constant field of an Enum? 3646 * Note: enum literals should not be regarded as such 3647 */ 3648 private boolean isStaticEnumField(VarSymbol v) { 3649 return Flags.isEnum(v.owner) && 3650 Flags.isStatic(v) && 3651 !Flags.isConstant(v) && 3652 v.name != names._class; 3653 } 3654 3655 /** Can the given symbol be the owner of code which forms part 3656 * if class initialization? This is the case if the symbol is 3657 * a type or field, or if the symbol is the synthetic method. 3658 * owning a block. 3659 */ 3660 private boolean canOwnInitializer(Symbol sym) { 3661 return 3662 (sym.kind & (VAR | TYP)) != 0 || 3663 (sym.kind == MTH && (sym.flags() & BLOCK) != 0); 3664 } 3665 3666 Warner noteWarner = new Warner(); 3667 3668 /** 3669 * Check that method arguments conform to its instantiation. 3670 **/ 3671 public Type checkMethod(Type site, 3672 Symbol sym, 3673 ResultInfo resultInfo, 3674 Env<AttrContext> env, 3675 final List<JCExpression> argtrees, 3676 List<Type> argtypes, 3677 List<Type> typeargtypes) { 3678 // Test (5): if symbol is an instance method of a raw type, issue 3679 // an unchecked warning if its argument types change under erasure. 3680 if (allowGenerics && 3681 (sym.flags() & STATIC) == 0 && 3682 (site.hasTag(CLASS) || site.hasTag(TYPEVAR))) { 3683 Type s = types.asOuterSuper(site, sym.owner); 3684 if (s != null && s.isRaw() && 3685 !types.isSameTypes(sym.type.getParameterTypes(), 3686 sym.erasure(types).getParameterTypes())) { 3687 chk.warnUnchecked(env.tree.pos(), 3688 "unchecked.call.mbr.of.raw.type", 3689 sym, s); 3690 } 3691 } 3692 3693 if (env.info.defaultSuperCallSite != null) { 3694 for (Type sup : types.interfaces(env.enclClass.type).prepend(types.supertype((env.enclClass.type)))) { 3695 if (!sup.tsym.isSubClass(sym.enclClass(), types) || 3696 types.isSameType(sup, env.info.defaultSuperCallSite)) continue; 3697 List<MethodSymbol> icand_sup = 3698 types.interfaceCandidates(sup, (MethodSymbol)sym); 3699 if (icand_sup.nonEmpty() && 3700 icand_sup.head != sym && 3701 icand_sup.head.overrides(sym, icand_sup.head.enclClass(), types, true)) { 3702 log.error(env.tree.pos(), "illegal.default.super.call", env.info.defaultSuperCallSite, 3703 diags.fragment("overridden.default", sym, sup)); 3704 break; 3705 } 3706 } 3707 env.info.defaultSuperCallSite = null; 3708 } 3709 3710 if (sym.isStatic() && site.isInterface() && env.tree.hasTag(APPLY)) { 3711 JCMethodInvocation app = (JCMethodInvocation)env.tree; 3712 if (app.meth.hasTag(SELECT) && 3713 !TreeInfo.isStaticSelector(((JCFieldAccess)app.meth).selected, names)) { 3714 log.error(env.tree.pos(), "illegal.static.intf.meth.call", site); 3715 } 3716 } 3717 3718 // Compute the identifier's instantiated type. 3719 // For methods, we need to compute the instance type by 3720 // Resolve.instantiate from the symbol's type as well as 3721 // any type arguments and value arguments. 3722 noteWarner.clear(); 3723 try { 3724 Type owntype = rs.checkMethod( 3725 env, 3726 site, 3727 sym, 3728 resultInfo, 3729 argtypes, 3730 typeargtypes, 3731 noteWarner); 3732 3733 DeferredAttr.DeferredTypeMap checkDeferredMap = 3734 deferredAttr.new DeferredTypeMap(DeferredAttr.AttrMode.CHECK, sym, env.info.pendingResolutionPhase); 3735 3736 argtypes = Type.map(argtypes, checkDeferredMap); 3737 3738 if (noteWarner.hasNonSilentLint(LintCategory.UNCHECKED)) { 3739 chk.warnUnchecked(env.tree.pos(), 3740 "unchecked.meth.invocation.applied", 3741 kindName(sym), 3742 sym.name, 3743 rs.methodArguments(sym.type.getParameterTypes()), 3744 rs.methodArguments(Type.map(argtypes, checkDeferredMap)), 3745 kindName(sym.location()), 3746 sym.location()); 3747 owntype = new MethodType(owntype.getParameterTypes(), 3748 types.erasure(owntype.getReturnType()), 3749 types.erasure(owntype.getThrownTypes()), 3750 syms.methodClass); 3751 } 3752 3753 return chk.checkMethod(owntype, sym, env, argtrees, argtypes, env.info.lastResolveVarargs(), 3754 resultInfo.checkContext.inferenceContext()); 3755 } catch (Infer.InferenceException ex) { 3756 //invalid target type - propagate exception outwards or report error 3757 //depending on the current check context 3758 resultInfo.checkContext.report(env.tree.pos(), ex.getDiagnostic()); 3759 return types.createErrorType(site); 3760 } catch (Resolve.InapplicableMethodException ex) { 3761 Assert.error(ex.getDiagnostic().getMessage(Locale.getDefault())); 3762 return null; 3763 } 3764 } 3765 3766 public void visitLiteral(JCLiteral tree) { 3767 result = check( 3768 tree, litType(tree.typetag).constType(tree.value), VAL, resultInfo); 3769 } 3770 //where 3771 /** Return the type of a literal with given type tag. 3772 */ 3773 Type litType(TypeTag tag) { 3774 return (tag == CLASS) ? syms.stringType : syms.typeOfTag[tag.ordinal()]; 3775 } 3776 3777 public void visitTypeIdent(JCPrimitiveTypeTree tree) { 3778 result = check(tree, syms.typeOfTag[tree.typetag.ordinal()], TYP, resultInfo); 3779 } 3780 3781 public void visitTypeArray(JCArrayTypeTree tree) { 3782 Type etype = attribType(tree.elemtype, env); 3783 Type type = new ArrayType(etype, syms.arrayClass); 3784 result = check(tree, type, TYP, resultInfo); 3785 } 3786 3787 /** Visitor method for parameterized types. 3788 * Bound checking is left until later, since types are attributed 3789 * before supertype structure is completely known 3790 */ 3791 public void visitTypeApply(JCTypeApply tree) { 3792 Type owntype = types.createErrorType(tree.type); 3793 3794 // Attribute functor part of application and make sure it's a class. 3795 Type clazztype = chk.checkClassType(tree.clazz.pos(), attribType(tree.clazz, env)); 3796 3797 // Attribute type parameters 3798 List<Type> actuals = attribTypes(tree.arguments, env); 3799 3800 if (clazztype.hasTag(CLASS)) { 3801 List<Type> formals = clazztype.tsym.type.getTypeArguments(); 3802 if (actuals.isEmpty()) //diamond 3803 actuals = formals; 3804 3805 if (actuals.length() == formals.length()) { 3806 List<Type> a = actuals; 3807 List<Type> f = formals; 3808 while (a.nonEmpty()) { 3809 a.head = a.head.withTypeVar(f.head); 3810 a = a.tail; 3811 f = f.tail; 3812 } 3813 // Compute the proper generic outer 3814 Type clazzOuter = clazztype.getEnclosingType(); 3815 if (clazzOuter.hasTag(CLASS)) { 3816 Type site; 3817 JCExpression clazz = TreeInfo.typeIn(tree.clazz); 3818 if (clazz.hasTag(IDENT)) { 3819 site = env.enclClass.sym.type; 3820 } else if (clazz.hasTag(SELECT)) { 3821 site = ((JCFieldAccess) clazz).selected.type; 3822 } else throw new AssertionError(""+tree); 3823 if (clazzOuter.hasTag(CLASS) && site != clazzOuter) { 3824 if (site.hasTag(CLASS)) 3825 site = types.asOuterSuper(site, clazzOuter.tsym); 3826 if (site == null) 3827 site = types.erasure(clazzOuter); 3828 clazzOuter = site; 3829 } 3830 } 3831 owntype = new ClassType(clazzOuter, actuals, clazztype.tsym); 3832 if (clazztype.isAnnotated()) { 3833 // Use the same AnnotatedType, because it will have 3834 // its annotations set later. 3835 ((AnnotatedType)clazztype).underlyingType = owntype; 3836 owntype = clazztype; 3837 } 3838 } else { 3839 if (formals.length() != 0) { 3840 log.error(tree.pos(), "wrong.number.type.args", 3841 Integer.toString(formals.length())); 3842 } else { 3843 log.error(tree.pos(), "type.doesnt.take.params", clazztype.tsym); 3844 } 3845 owntype = types.createErrorType(tree.type); 3846 } 3847 } 3848 result = check(tree, owntype, TYP, resultInfo); 3849 } 3850 3851 public void visitTypeUnion(JCTypeUnion tree) { 3852 ListBuffer<Type> multicatchTypes = ListBuffer.lb(); 3853 ListBuffer<Type> all_multicatchTypes = null; // lazy, only if needed 3854 for (JCExpression typeTree : tree.alternatives) { 3855 Type ctype = attribType(typeTree, env); 3856 ctype = chk.checkType(typeTree.pos(), 3857 chk.checkClassType(typeTree.pos(), ctype), 3858 syms.throwableType); 3859 if (!ctype.isErroneous()) { 3860 //check that alternatives of a union type are pairwise 3861 //unrelated w.r.t. subtyping 3862 if (chk.intersects(ctype, multicatchTypes.toList())) { 3863 for (Type t : multicatchTypes) { 3864 boolean sub = types.isSubtype(ctype, t); 3865 boolean sup = types.isSubtype(t, ctype); 3866 if (sub || sup) { 3867 //assume 'a' <: 'b' 3868 Type a = sub ? ctype : t; 3869 Type b = sub ? t : ctype; 3870 log.error(typeTree.pos(), "multicatch.types.must.be.disjoint", a, b); 3871 } 3872 } 3873 } 3874 multicatchTypes.append(ctype); 3875 if (all_multicatchTypes != null) 3876 all_multicatchTypes.append(ctype); 3877 } else { 3878 if (all_multicatchTypes == null) { 3879 all_multicatchTypes = ListBuffer.lb(); 3880 all_multicatchTypes.appendList(multicatchTypes); 3881 } 3882 all_multicatchTypes.append(ctype); 3883 } 3884 } 3885 Type t = check(tree, types.lub(multicatchTypes.toList()), TYP, resultInfo); 3886 if (t.hasTag(CLASS)) { 3887 List<Type> alternatives = 3888 ((all_multicatchTypes == null) ? multicatchTypes : all_multicatchTypes).toList(); 3889 t = new UnionClassType((ClassType) t, alternatives); 3890 } 3891 tree.type = result = t; 3892 } 3893 3894 public void visitTypeIntersection(JCTypeIntersection tree) { 3895 attribTypes(tree.bounds, env); 3896 tree.type = result = checkIntersection(tree, tree.bounds); 3897 } 3898 3899 public void visitTypeParameter(JCTypeParameter tree) { 3900 TypeVar typeVar = (TypeVar) tree.type; 3901 3902 if (tree.annotations != null && tree.annotations.nonEmpty()) { 3903 AnnotatedType antype = new AnnotatedType(typeVar); 3904 annotateType(antype, tree.annotations); 3905 tree.type = antype; 3906 } 3907 3908 if (!typeVar.bound.isErroneous()) { 3909 //fixup type-parameter bound computed in 'attribTypeVariables' 3910 typeVar.bound = checkIntersection(tree, tree.bounds); 3911 } 3912 } 3913 3914 Type checkIntersection(JCTree tree, List<JCExpression> bounds) { 3915 Set<Type> boundSet = new HashSet<Type>(); 3916 if (bounds.nonEmpty()) { 3917 // accept class or interface or typevar as first bound. 3918 bounds.head.type = checkBase(bounds.head.type, bounds.head, env, false, false, false); 3919 boundSet.add(types.erasure(bounds.head.type)); 3920 if (bounds.head.type.isErroneous()) { 3921 return bounds.head.type; 3922 } 3923 else if (bounds.head.type.hasTag(TYPEVAR)) { 3924 // if first bound was a typevar, do not accept further bounds. 3925 if (bounds.tail.nonEmpty()) { 3926 log.error(bounds.tail.head.pos(), 3927 "type.var.may.not.be.followed.by.other.bounds"); 3928 return bounds.head.type; 3929 } 3930 } else { 3931 // if first bound was a class or interface, accept only interfaces 3932 // as further bounds. 3933 for (JCExpression bound : bounds.tail) { 3934 bound.type = checkBase(bound.type, bound, env, false, true, false); 3935 if (bound.type.isErroneous()) { 3936 bounds = List.of(bound); 3937 } 3938 else if (bound.type.hasTag(CLASS)) { 3939 chk.checkNotRepeated(bound.pos(), types.erasure(bound.type), boundSet); 3940 } 3941 } 3942 } 3943 } 3944 3945 if (bounds.length() == 0) { 3946 return syms.objectType; 3947 } else if (bounds.length() == 1) { 3948 return bounds.head.type; 3949 } else { 3950 Type owntype = types.makeCompoundType(TreeInfo.types(bounds)); 3951 if (tree.hasTag(TYPEINTERSECTION)) { 3952 ((IntersectionClassType)owntype).intersectionKind = 3953 IntersectionClassType.IntersectionKind.EXPLICIT; 3954 } 3955 // ... the variable's bound is a class type flagged COMPOUND 3956 // (see comment for TypeVar.bound). 3957 // In this case, generate a class tree that represents the 3958 // bound class, ... 3959 JCExpression extending; 3960 List<JCExpression> implementing; 3961 if (!bounds.head.type.isInterface()) { 3962 extending = bounds.head; 3963 implementing = bounds.tail; 3964 } else { 3965 extending = null; 3966 implementing = bounds; 3967 } 3968 JCClassDecl cd = make.at(tree).ClassDef( 3969 make.Modifiers(PUBLIC | ABSTRACT), 3970 names.empty, List.<JCTypeParameter>nil(), 3971 extending, implementing, List.<JCTree>nil()); 3972 3973 ClassSymbol c = (ClassSymbol)owntype.tsym; 3974 Assert.check((c.flags() & COMPOUND) != 0); 3975 cd.sym = c; 3976 c.sourcefile = env.toplevel.sourcefile; 3977 3978 // ... and attribute the bound class 3979 c.flags_field |= UNATTRIBUTED; 3980 Env<AttrContext> cenv = enter.classEnv(cd, env); 3981 enter.typeEnvs.put(c, cenv); 3982 attribClass(c); 3983 return owntype; 3984 } 3985 } 3986 3987 public void visitWildcard(JCWildcard tree) { 3988 //- System.err.println("visitWildcard("+tree+");");//DEBUG 3989 Type type = (tree.kind.kind == BoundKind.UNBOUND) 3990 ? syms.objectType 3991 : attribType(tree.inner, env); 3992 result = check(tree, new WildcardType(chk.checkRefType(tree.pos(), type), 3993 tree.kind.kind, 3994 syms.boundClass), 3995 TYP, resultInfo); 3996 } 3997 3998 public void visitAnnotation(JCAnnotation tree) { 3999 log.error(tree.pos(), "annotation.not.valid.for.type", pt()); 4000 result = tree.type = syms.errType; 4001 } 4002 4003 public void visitAnnotatedType(JCAnnotatedType tree) { 4004 Type underlyingType = attribType(tree.getUnderlyingType(), env); 4005 this.attribAnnotationTypes(tree.annotations, env); 4006 AnnotatedType antype = new AnnotatedType(underlyingType); 4007 annotateType(antype, tree.annotations); 4008 result = tree.type = antype; 4009 } 4010 4011 /** 4012 * Apply the annotations to the particular type. 4013 */ 4014 public void annotateType(final AnnotatedType type, final List<JCAnnotation> annotations) { 4015 if (annotations.isEmpty()) 4016 return; 4017 annotate.typeAnnotation(new Annotate.Annotator() { 4018 @Override 4019 public String toString() { 4020 return "annotate " + annotations + " onto " + type; 4021 } 4022 @Override 4023 public void enterAnnotation() { 4024 List<Attribute.TypeCompound> compounds = fromAnnotations(annotations); 4025 type.typeAnnotations = compounds; 4026 } 4027 }); 4028 } 4029 4030 private static List<Attribute.TypeCompound> fromAnnotations(List<JCAnnotation> annotations) { 4031 if (annotations.isEmpty()) 4032 return List.nil(); 4033 4034 ListBuffer<Attribute.TypeCompound> buf = ListBuffer.lb(); 4035 for (JCAnnotation anno : annotations) { 4036 if (anno.attribute != null) { 4037 // TODO: this null-check is only needed for an obscure 4038 // ordering issue, where annotate.flush is called when 4039 // the attribute is not set yet. For an example failure 4040 // try the referenceinfos/NestedTypes.java test. 4041 // Any better solutions? 4042 buf.append((Attribute.TypeCompound) anno.attribute); 4043 } 4044 } 4045 return buf.toList(); 4046 } 4047 4048 public void visitErroneous(JCErroneous tree) { 4049 if (tree.errs != null) 4050 for (JCTree err : tree.errs) 4051 attribTree(err, env, new ResultInfo(ERR, pt())); 4052 result = tree.type = syms.errType; 4053 } 4054 4055 /** Default visitor method for all other trees. 4056 */ 4057 public void visitTree(JCTree tree) { 4058 throw new AssertionError(); 4059 } 4060 4061 /** 4062 * Attribute an env for either a top level tree or class declaration. 4063 */ 4064 public void attrib(Env<AttrContext> env) { 4065 if (env.tree.hasTag(TOPLEVEL)) 4066 attribTopLevel(env); 4067 else 4068 attribClass(env.tree.pos(), env.enclClass.sym); 4069 } 4070 4071 /** 4072 * Attribute a top level tree. These trees are encountered when the 4073 * package declaration has annotations. 4074 */ 4075 public void attribTopLevel(Env<AttrContext> env) { 4076 JCCompilationUnit toplevel = env.toplevel; 4077 try { 4078 annotate.flush(); 4079 chk.validateAnnotations(toplevel.packageAnnotations, toplevel.packge); 4080 } catch (CompletionFailure ex) { 4081 chk.completionError(toplevel.pos(), ex); 4082 } 4083 } 4084 4085 /** Main method: attribute class definition associated with given class symbol. 4086 * reporting completion failures at the given position. 4087 * @param pos The source position at which completion errors are to be 4088 * reported. 4089 * @param c The class symbol whose definition will be attributed. 4090 */ 4091 public void attribClass(DiagnosticPosition pos, ClassSymbol c) { 4092 try { 4093 annotate.flush(); 4094 attribClass(c); 4095 } catch (CompletionFailure ex) { 4096 chk.completionError(pos, ex); 4097 } 4098 } 4099 4100 /** Attribute class definition associated with given class symbol. 4101 * @param c The class symbol whose definition will be attributed. 4102 */ 4103 void attribClass(ClassSymbol c) throws CompletionFailure { 4104 if (c.type.hasTag(ERROR)) return; 4105 4106 // Check for cycles in the inheritance graph, which can arise from 4107 // ill-formed class files. 4108 chk.checkNonCyclic(null, c.type); 4109 4110 Type st = types.supertype(c.type); 4111 if ((c.flags_field & Flags.COMPOUND) == 0) { 4112 // First, attribute superclass. 4113 if (st.hasTag(CLASS)) 4114 attribClass((ClassSymbol)st.tsym); 4115 4116 // Next attribute owner, if it is a class. 4117 if (c.owner.kind == TYP && c.owner.type.hasTag(CLASS)) 4118 attribClass((ClassSymbol)c.owner); 4119 } 4120 4121 // The previous operations might have attributed the current class 4122 // if there was a cycle. So we test first whether the class is still 4123 // UNATTRIBUTED. 4124 if ((c.flags_field & UNATTRIBUTED) != 0) { 4125 c.flags_field &= ~UNATTRIBUTED; 4126 4127 // Get environment current at the point of class definition. 4128 Env<AttrContext> env = enter.typeEnvs.get(c); 4129 4130 // The info.lint field in the envs stored in enter.typeEnvs is deliberately uninitialized, 4131 // because the annotations were not available at the time the env was created. Therefore, 4132 // we look up the environment chain for the first enclosing environment for which the 4133 // lint value is set. Typically, this is the parent env, but might be further if there 4134 // are any envs created as a result of TypeParameter nodes. 4135 Env<AttrContext> lintEnv = env; 4136 while (lintEnv.info.lint == null) 4137 lintEnv = lintEnv.next; 4138 4139 // Having found the enclosing lint value, we can initialize the lint value for this class 4140 env.info.lint = lintEnv.info.lint.augment(c); 4141 4142 Lint prevLint = chk.setLint(env.info.lint); 4143 JavaFileObject prev = log.useSource(c.sourcefile); 4144 ResultInfo prevReturnRes = env.info.returnResult; 4145 4146 try { 4147 env.info.returnResult = null; 4148 // java.lang.Enum may not be subclassed by a non-enum 4149 if (st.tsym == syms.enumSym && 4150 ((c.flags_field & (Flags.ENUM|Flags.COMPOUND)) == 0)) 4151 log.error(env.tree.pos(), "enum.no.subclassing"); 4152 4153 // Enums may not be extended by source-level classes 4154 if (st.tsym != null && 4155 ((st.tsym.flags_field & Flags.ENUM) != 0) && 4156 ((c.flags_field & (Flags.ENUM | Flags.COMPOUND)) == 0)) { 4157 log.error(env.tree.pos(), "enum.types.not.extensible"); 4158 } 4159 attribClassBody(env, c); 4160 4161 chk.checkDeprecatedAnnotation(env.tree.pos(), c); 4162 chk.checkClassOverrideEqualsAndHashIfNeeded(env.tree.pos(), c); 4163 } finally { 4164 env.info.returnResult = prevReturnRes; 4165 log.useSource(prev); 4166 chk.setLint(prevLint); 4167 } 4168 4169 } 4170 } 4171 4172 public void visitImport(JCImport tree) { 4173 // nothing to do 4174 } 4175 4176 /** Finish the attribution of a class. */ 4177 private void attribClassBody(Env<AttrContext> env, ClassSymbol c) { 4178 JCClassDecl tree = (JCClassDecl)env.tree; 4179 Assert.check(c == tree.sym); 4180 4181 // Validate annotations 4182 chk.validateAnnotations(tree.mods.annotations, c); 4183 4184 // Validate type parameters, supertype and interfaces. 4185 attribStats(tree.typarams, env); 4186 if (!c.isAnonymous()) { 4187 //already checked if anonymous 4188 chk.validate(tree.typarams, env); 4189 chk.validate(tree.extending, env); 4190 chk.validate(tree.implementing, env); 4191 } 4192 4193 // If this is a non-abstract class, check that it has no abstract 4194 // methods or unimplemented methods of an implemented interface. 4195 if ((c.flags() & (ABSTRACT | INTERFACE)) == 0) { 4196 if (!relax) 4197 chk.checkAllDefined(tree.pos(), c); 4198 } 4199 4200 if ((c.flags() & ANNOTATION) != 0) { 4201 if (tree.implementing.nonEmpty()) 4202 log.error(tree.implementing.head.pos(), 4203 "cant.extend.intf.annotation"); 4204 if (tree.typarams.nonEmpty()) 4205 log.error(tree.typarams.head.pos(), 4206 "intf.annotation.cant.have.type.params"); 4207 4208 // If this annotation has a @Repeatable, validate 4209 Attribute.Compound repeatable = c.attribute(syms.repeatableType.tsym); 4210 if (repeatable != null) { 4211 // get diagnostic position for error reporting 4212 DiagnosticPosition cbPos = getDiagnosticPosition(tree, repeatable.type); 4213 Assert.checkNonNull(cbPos); 4214 4215 chk.validateRepeatable(c, repeatable, cbPos); 4216 } 4217 } else { 4218 // Check that all extended classes and interfaces 4219 // are compatible (i.e. no two define methods with same arguments 4220 // yet different return types). (JLS 8.4.6.3) 4221 chk.checkCompatibleSupertypes(tree.pos(), c.type); 4222 if (allowDefaultMethods) { 4223 chk.checkDefaultMethodClashes(tree.pos(), c.type); 4224 } 4225 } 4226 4227 // Check that class does not import the same parameterized interface 4228 // with two different argument lists. 4229 chk.checkClassBounds(tree.pos(), c.type); 4230 4231 tree.type = c.type; 4232 4233 for (List<JCTypeParameter> l = tree.typarams; 4234 l.nonEmpty(); l = l.tail) { 4235 Assert.checkNonNull(env.info.scope.lookup(l.head.name).scope); 4236 } 4237 4238 // Check that a generic class doesn't extend Throwable 4239 if (!c.type.allparams().isEmpty() && types.isSubtype(c.type, syms.throwableType)) 4240 log.error(tree.extending.pos(), "generic.throwable"); 4241 4242 // Check that all methods which implement some 4243 // method conform to the method they implement. 4244 chk.checkImplementations(tree); 4245 4246 //check that a resource implementing AutoCloseable cannot throw InterruptedException 4247 checkAutoCloseable(tree.pos(), env, c.type); 4248 4249 for (List<JCTree> l = tree.defs; l.nonEmpty(); l = l.tail) { 4250 // Attribute declaration 4251 attribStat(l.head, env); 4252 // Check that declarations in inner classes are not static (JLS 8.1.2) 4253 // Make an exception for static constants. 4254 if (c.owner.kind != PCK && 4255 ((c.flags() & STATIC) == 0 || c.name == names.empty) && 4256 (TreeInfo.flags(l.head) & (STATIC | INTERFACE)) != 0) { 4257 Symbol sym = null; 4258 if (l.head.hasTag(VARDEF)) sym = ((JCVariableDecl) l.head).sym; 4259 if (sym == null || 4260 sym.kind != VAR || 4261 ((VarSymbol) sym).getConstValue() == null) 4262 log.error(l.head.pos(), "icls.cant.have.static.decl", c); 4263 } 4264 } 4265 4266 // Check for cycles among non-initial constructors. 4267 chk.checkCyclicConstructors(tree); 4268 4269 // Check for cycles among annotation elements. 4270 chk.checkNonCyclicElements(tree); 4271 4272 // Check for proper use of serialVersionUID 4273 if (env.info.lint.isEnabled(LintCategory.SERIAL) && 4274 isSerializable(c) && 4275 (c.flags() & Flags.ENUM) == 0 && 4276 (c.flags() & ABSTRACT) == 0) { 4277 checkSerialVersionUID(tree, c); 4278 } 4279 4280 // Correctly organize the postions of the type annotations 4281 TypeAnnotations.organizeTypeAnnotationsBodies(this.syms, this.names, this.log, tree); 4282 4283 // Check type annotations applicability rules 4284 validateTypeAnnotations(tree); 4285 } 4286 // where 4287 /** get a diagnostic position for an attribute of Type t, or null if attribute missing */ 4288 private DiagnosticPosition getDiagnosticPosition(JCClassDecl tree, Type t) { 4289 for(List<JCAnnotation> al = tree.mods.annotations; !al.isEmpty(); al = al.tail) { 4290 if (types.isSameType(al.head.annotationType.type, t)) 4291 return al.head.pos(); 4292 } 4293 4294 return null; 4295 } 4296 4297 /** check if a class is a subtype of Serializable, if that is available. */ 4298 private boolean isSerializable(ClassSymbol c) { 4299 try { 4300 syms.serializableType.complete(); 4301 } 4302 catch (CompletionFailure e) { 4303 return false; 4304 } 4305 return types.isSubtype(c.type, syms.serializableType); 4306 } 4307 4308 /** Check that an appropriate serialVersionUID member is defined. */ 4309 private void checkSerialVersionUID(JCClassDecl tree, ClassSymbol c) { 4310 4311 // check for presence of serialVersionUID 4312 Scope.Entry e = c.members().lookup(names.serialVersionUID); 4313 while (e.scope != null && e.sym.kind != VAR) e = e.next(); 4314 if (e.scope == null) { 4315 log.warning(LintCategory.SERIAL, 4316 tree.pos(), "missing.SVUID", c); 4317 return; 4318 } 4319 4320 // check that it is static final 4321 VarSymbol svuid = (VarSymbol)e.sym; 4322 if ((svuid.flags() & (STATIC | FINAL)) != 4323 (STATIC | FINAL)) 4324 log.warning(LintCategory.SERIAL, 4325 TreeInfo.diagnosticPositionFor(svuid, tree), "improper.SVUID", c); 4326 4327 // check that it is long 4328 else if (!svuid.type.hasTag(LONG)) 4329 log.warning(LintCategory.SERIAL, 4330 TreeInfo.diagnosticPositionFor(svuid, tree), "long.SVUID", c); 4331 4332 // check constant 4333 else if (svuid.getConstValue() == null) 4334 log.warning(LintCategory.SERIAL, 4335 TreeInfo.diagnosticPositionFor(svuid, tree), "constant.SVUID", c); 4336 } 4337 4338 private Type capture(Type type) { 4339 //do not capture free types 4340 return resultInfo.checkContext.inferenceContext().free(type) ? 4341 type : types.capture(type); 4342 } 4343 4344 private void validateTypeAnnotations(JCTree tree) { 4345 tree.accept(typeAnnotationsValidator); 4346 } 4347 //where 4348 private final JCTree.Visitor typeAnnotationsValidator = new TreeScanner() { 4349 4350 private boolean checkAllAnnotations = false; 4351 4352 public void visitAnnotation(JCAnnotation tree) { 4353 if (tree.hasTag(TYPE_ANNOTATION) || checkAllAnnotations) { 4354 chk.validateTypeAnnotation(tree, false); 4355 } 4356 super.visitAnnotation(tree); 4357 } 4358 public void visitTypeParameter(JCTypeParameter tree) { 4359 chk.validateTypeAnnotations(tree.annotations, true); 4360 scan(tree.bounds); 4361 // Don't call super. 4362 // This is needed because above we call validateTypeAnnotation with 4363 // false, which would forbid annotations on type parameters. 4364 // super.visitTypeParameter(tree); 4365 } 4366 public void visitMethodDef(JCMethodDecl tree) { 4367 if (tree.recvparam != null && 4368 tree.recvparam.vartype.type.getKind() != TypeKind.ERROR) { 4369 checkForDeclarationAnnotations(tree.recvparam.mods.annotations, 4370 tree.recvparam.vartype.type.tsym); 4371 } 4372 if (tree.restype != null && tree.restype.type != null) { 4373 validateAnnotatedType(tree.restype, tree.restype.type); 4374 } 4375 super.visitMethodDef(tree); 4376 } 4377 public void visitVarDef(final JCVariableDecl tree) { 4378 if (tree.sym != null && tree.sym.type != null) 4379 validateAnnotatedType(tree, tree.sym.type); 4380 super.visitVarDef(tree); 4381 } 4382 public void visitTypeCast(JCTypeCast tree) { 4383 if (tree.clazz != null && tree.clazz.type != null) 4384 validateAnnotatedType(tree.clazz, tree.clazz.type); 4385 super.visitTypeCast(tree); 4386 } 4387 public void visitTypeTest(JCInstanceOf tree) { 4388 if (tree.clazz != null && tree.clazz.type != null) 4389 validateAnnotatedType(tree.clazz, tree.clazz.type); 4390 super.visitTypeTest(tree); 4391 } 4392 public void visitNewClass(JCNewClass tree) { 4393 if (tree.clazz.hasTag(ANNOTATED_TYPE)) { 4394 boolean prevCheck = this.checkAllAnnotations; 4395 try { 4396 this.checkAllAnnotations = true; 4397 scan(((JCAnnotatedType)tree.clazz).annotations); 4398 } finally { 4399 this.checkAllAnnotations = prevCheck; 4400 } 4401 } 4402 super.visitNewClass(tree); 4403 } 4404 public void visitNewArray(JCNewArray tree) { 4405 if (tree.elemtype != null && tree.elemtype.hasTag(ANNOTATED_TYPE)) { 4406 boolean prevCheck = this.checkAllAnnotations; 4407 try { 4408 this.checkAllAnnotations = true; 4409 scan(((JCAnnotatedType)tree.elemtype).annotations); 4410 } finally { 4411 this.checkAllAnnotations = prevCheck; 4412 } 4413 } 4414 super.visitNewArray(tree); 4415 } 4416 4417 /* I would want to model this after 4418 * com.sun.tools.javac.comp.Check.Validator.visitSelectInternal(JCFieldAccess) 4419 * and override visitSelect and visitTypeApply. 4420 * However, we only set the annotated type in the top-level type 4421 * of the symbol. 4422 * Therefore, we need to override each individual location where a type 4423 * can occur. 4424 */ 4425 private void validateAnnotatedType(final JCTree errtree, final Type type) { 4426 if (type.getEnclosingType() != null && 4427 type != type.getEnclosingType()) { 4428 validateEnclosingAnnotatedType(errtree, type.getEnclosingType()); 4429 } 4430 for (Type targ : type.getTypeArguments()) { 4431 validateAnnotatedType(errtree, targ); 4432 } 4433 } 4434 private void validateEnclosingAnnotatedType(final JCTree errtree, final Type type) { 4435 validateAnnotatedType(errtree, type); 4436 if (type.tsym != null && 4437 type.tsym.isStatic() && 4438 type.getAnnotationMirrors().nonEmpty()) { 4439 // Enclosing static classes cannot have type annotations. 4440 log.error(errtree.pos(), "cant.annotate.static.class"); 4441 } 4442 } 4443 }; 4444 4445 // <editor-fold desc="post-attribution visitor"> 4446 4447 /** 4448 * Handle missing types/symbols in an AST. This routine is useful when 4449 * the compiler has encountered some errors (which might have ended up 4450 * terminating attribution abruptly); if the compiler is used in fail-over 4451 * mode (e.g. by an IDE) and the AST contains semantic errors, this routine 4452 * prevents NPE to be progagated during subsequent compilation steps. 4453 */ 4454 public void postAttr(JCTree tree) { 4455 new PostAttrAnalyzer().scan(tree); 4456 } 4457 4458 class PostAttrAnalyzer extends TreeScanner { 4459 4460 private void initTypeIfNeeded(JCTree that) { 4461 if (that.type == null) { 4462 that.type = syms.unknownType; 4463 } 4464 } 4465 4466 @Override 4467 public void scan(JCTree tree) { 4468 if (tree == null) return; 4469 if (tree instanceof JCExpression) { 4470 initTypeIfNeeded(tree); 4471 } 4472 super.scan(tree); 4473 } 4474 4475 @Override 4476 public void visitIdent(JCIdent that) { 4477 if (that.sym == null) { 4478 that.sym = syms.unknownSymbol; 4479 } 4480 } 4481 4482 @Override 4483 public void visitSelect(JCFieldAccess that) { 4484 if (that.sym == null) { 4485 that.sym = syms.unknownSymbol; 4486 } 4487 super.visitSelect(that); 4488 } 4489 4490 @Override 4491 public void visitClassDef(JCClassDecl that) { 4492 initTypeIfNeeded(that); 4493 if (that.sym == null) { 4494 that.sym = new ClassSymbol(0, that.name, that.type, syms.noSymbol); 4495 } 4496 super.visitClassDef(that); 4497 } 4498 4499 @Override 4500 public void visitMethodDef(JCMethodDecl that) { 4501 initTypeIfNeeded(that); 4502 if (that.sym == null) { 4503 that.sym = new MethodSymbol(0, that.name, that.type, syms.noSymbol); 4504 } 4505 super.visitMethodDef(that); 4506 } 4507 4508 @Override 4509 public void visitVarDef(JCVariableDecl that) { 4510 initTypeIfNeeded(that); 4511 if (that.sym == null) { 4512 that.sym = new VarSymbol(0, that.name, that.type, syms.noSymbol); 4513 that.sym.adr = 0; 4514 } 4515 super.visitVarDef(that); 4516 } 4517 4518 @Override 4519 public void visitNewClass(JCNewClass that) { 4520 if (that.constructor == null) { 4521 that.constructor = new MethodSymbol(0, names.init, syms.unknownType, syms.noSymbol); 4522 } 4523 if (that.constructorType == null) { 4524 that.constructorType = syms.unknownType; 4525 } 4526 super.visitNewClass(that); 4527 } 4528 4529 @Override 4530 public void visitAssignop(JCAssignOp that) { 4531 if (that.operator == null) 4532 that.operator = new OperatorSymbol(names.empty, syms.unknownType, -1, syms.noSymbol); 4533 super.visitAssignop(that); 4534 } 4535 4536 @Override 4537 public void visitBinary(JCBinary that) { 4538 if (that.operator == null) 4539 that.operator = new OperatorSymbol(names.empty, syms.unknownType, -1, syms.noSymbol); 4540 super.visitBinary(that); 4541 } 4542 4543 @Override 4544 public void visitUnary(JCUnary that) { 4545 if (that.operator == null) 4546 that.operator = new OperatorSymbol(names.empty, syms.unknownType, -1, syms.noSymbol); 4547 super.visitUnary(that); 4548 } 4549 4550 @Override 4551 public void visitLambda(JCLambda that) { 4552 super.visitLambda(that); 4553 if (that.descriptorType == null) { 4554 that.descriptorType = syms.unknownType; 4555 } 4556 if (that.targets == null) { 4557 that.targets = List.nil(); 4558 } 4559 } 4560 4561 @Override 4562 public void visitReference(JCMemberReference that) { 4563 super.visitReference(that); 4564 if (that.sym == null) { 4565 that.sym = new MethodSymbol(0, names.empty, syms.unknownType, syms.noSymbol); 4566 } 4567 if (that.descriptorType == null) { 4568 that.descriptorType = syms.unknownType; 4569 } 4570 if (that.targets == null) { 4571 that.targets = List.nil(); 4572 } 4573 } 4574 } 4575 // </editor-fold> 4576 }