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.tools.JavaFileManager; 31 32 import com.sun.tools.javac.code.*; 33 import com.sun.tools.javac.jvm.*; 34 import com.sun.tools.javac.tree.*; 35 import com.sun.tools.javac.util.*; 36 import com.sun.tools.javac.util.JCDiagnostic.DiagnosticPosition; 37 import com.sun.tools.javac.util.List; 38 39 import com.sun.tools.javac.code.Lint; 40 import com.sun.tools.javac.code.Lint.LintCategory; 41 import com.sun.tools.javac.code.Type.*; 42 import com.sun.tools.javac.code.Symbol.*; 43 import com.sun.tools.javac.comp.DeferredAttr.DeferredAttrContext; 44 import com.sun.tools.javac.comp.Infer.InferenceContext; 45 import com.sun.tools.javac.comp.Infer.FreeTypeListener; 46 import com.sun.tools.javac.tree.JCTree.*; 47 import com.sun.tools.javac.tree.JCTree.JCPolyExpression.*; 48 49 import static com.sun.tools.javac.code.Flags.*; 50 import static com.sun.tools.javac.code.Flags.ANNOTATION; 51 import static com.sun.tools.javac.code.Flags.SYNCHRONIZED; 52 import static com.sun.tools.javac.code.Kinds.*; 53 import static com.sun.tools.javac.code.TypeTag.*; 54 import static com.sun.tools.javac.code.TypeTag.WILDCARD; 55 56 import static com.sun.tools.javac.tree.JCTree.Tag.*; 57 58 /** Type checking helper class for the attribution phase. 59 * 60 * <p><b>This is NOT part of any supported API. 61 * If you write code that depends on this, you do so at your own risk. 62 * This code and its internal interfaces are subject to change or 63 * deletion without notice.</b> 64 */ 65 public class Check { 66 protected static final Context.Key<Check> checkKey = 67 new Context.Key<Check>(); 68 69 private final Names names; 70 private final Log log; 71 private final Resolve rs; 72 private final Symtab syms; 73 private final Enter enter; 74 private final DeferredAttr deferredAttr; 75 private final Infer infer; 76 private final Types types; 77 private final JCDiagnostic.Factory diags; 78 private boolean warnOnSyntheticConflicts; 79 private boolean suppressAbortOnBadClassFile; 80 private boolean enableSunApiLintControl; 81 private final TreeInfo treeinfo; 82 private final JavaFileManager fileManager; 83 private final Profile profile; 84 85 // The set of lint options currently in effect. It is initialized 86 // from the context, and then is set/reset as needed by Attr as it 87 // visits all the various parts of the trees during attribution. 88 private Lint lint; 89 90 // The method being analyzed in Attr - it is set/reset as needed by 91 // Attr as it visits new method declarations. 92 private MethodSymbol method; 93 94 public static Check instance(Context context) { 95 Check instance = context.get(checkKey); 96 if (instance == null) 97 instance = new Check(context); 98 return instance; 99 } 100 101 protected Check(Context context) { 102 context.put(checkKey, this); 103 104 names = Names.instance(context); 105 dfltTargetMeta = new Name[] { names.PACKAGE, names.TYPE, 106 names.FIELD, names.METHOD, names.CONSTRUCTOR, 107 names.ANNOTATION_TYPE, names.LOCAL_VARIABLE, names.PARAMETER}; 108 log = Log.instance(context); 109 rs = Resolve.instance(context); 110 syms = Symtab.instance(context); 111 enter = Enter.instance(context); 112 deferredAttr = DeferredAttr.instance(context); 113 infer = Infer.instance(context); 114 types = Types.instance(context); 115 diags = JCDiagnostic.Factory.instance(context); 116 Options options = Options.instance(context); 117 lint = Lint.instance(context); 118 treeinfo = TreeInfo.instance(context); 119 fileManager = context.get(JavaFileManager.class); 120 121 Source source = Source.instance(context); 122 allowGenerics = source.allowGenerics(); 123 allowVarargs = source.allowVarargs(); 124 allowAnnotations = source.allowAnnotations(); 125 allowCovariantReturns = source.allowCovariantReturns(); 126 allowSimplifiedVarargs = source.allowSimplifiedVarargs(); 127 allowDefaultMethods = source.allowDefaultMethods(); 128 allowStrictMethodClashCheck = source.allowStrictMethodClashCheck(); 129 complexInference = options.isSet("complexinference"); 130 warnOnSyntheticConflicts = options.isSet("warnOnSyntheticConflicts"); 131 suppressAbortOnBadClassFile = options.isSet("suppressAbortOnBadClassFile"); 132 enableSunApiLintControl = options.isSet("enableSunApiLintControl"); 133 134 Target target = Target.instance(context); 135 syntheticNameChar = target.syntheticNameChar(); 136 137 profile = Profile.instance(context); 138 139 boolean verboseDeprecated = lint.isEnabled(LintCategory.DEPRECATION); 140 boolean verboseUnchecked = lint.isEnabled(LintCategory.UNCHECKED); 141 boolean verboseSunApi = lint.isEnabled(LintCategory.SUNAPI); 142 boolean enforceMandatoryWarnings = source.enforceMandatoryWarnings(); 143 144 deprecationHandler = new MandatoryWarningHandler(log, verboseDeprecated, 145 enforceMandatoryWarnings, "deprecated", LintCategory.DEPRECATION); 146 uncheckedHandler = new MandatoryWarningHandler(log, verboseUnchecked, 147 enforceMandatoryWarnings, "unchecked", LintCategory.UNCHECKED); 148 sunApiHandler = new MandatoryWarningHandler(log, verboseSunApi, 149 enforceMandatoryWarnings, "sunapi", null); 150 151 deferredLintHandler = DeferredLintHandler.instance(context); 152 } 153 154 /** Switch: generics enabled? 155 */ 156 boolean allowGenerics; 157 158 /** Switch: varargs enabled? 159 */ 160 boolean allowVarargs; 161 162 /** Switch: annotations enabled? 163 */ 164 boolean allowAnnotations; 165 166 /** Switch: covariant returns enabled? 167 */ 168 boolean allowCovariantReturns; 169 170 /** Switch: simplified varargs enabled? 171 */ 172 boolean allowSimplifiedVarargs; 173 174 /** Switch: default methods enabled? 175 */ 176 boolean allowDefaultMethods; 177 178 /** Switch: should unrelated return types trigger a method clash? 179 */ 180 boolean allowStrictMethodClashCheck; 181 182 /** Switch: -complexinference option set? 183 */ 184 boolean complexInference; 185 186 /** Character for synthetic names 187 */ 188 char syntheticNameChar; 189 190 /** A table mapping flat names of all compiled classes in this run to their 191 * symbols; maintained from outside. 192 */ 193 public Map<Name,ClassSymbol> compiled = new HashMap<Name, ClassSymbol>(); 194 195 /** A handler for messages about deprecated usage. 196 */ 197 private MandatoryWarningHandler deprecationHandler; 198 199 /** A handler for messages about unchecked or unsafe usage. 200 */ 201 private MandatoryWarningHandler uncheckedHandler; 202 203 /** A handler for messages about using proprietary API. 204 */ 205 private MandatoryWarningHandler sunApiHandler; 206 207 /** A handler for deferred lint warnings. 208 */ 209 private DeferredLintHandler deferredLintHandler; 210 211 /* ************************************************************************* 212 * Errors and Warnings 213 **************************************************************************/ 214 215 Lint setLint(Lint newLint) { 216 Lint prev = lint; 217 lint = newLint; 218 return prev; 219 } 220 221 MethodSymbol setMethod(MethodSymbol newMethod) { 222 MethodSymbol prev = method; 223 method = newMethod; 224 return prev; 225 } 226 227 /** Warn about deprecated symbol. 228 * @param pos Position to be used for error reporting. 229 * @param sym The deprecated symbol. 230 */ 231 void warnDeprecated(DiagnosticPosition pos, Symbol sym) { 232 if (!lint.isSuppressed(LintCategory.DEPRECATION)) 233 deprecationHandler.report(pos, "has.been.deprecated", sym, sym.location()); 234 } 235 236 /** Warn about unchecked operation. 237 * @param pos Position to be used for error reporting. 238 * @param msg A string describing the problem. 239 */ 240 public void warnUnchecked(DiagnosticPosition pos, String msg, Object... args) { 241 if (!lint.isSuppressed(LintCategory.UNCHECKED)) 242 uncheckedHandler.report(pos, msg, args); 243 } 244 245 /** Warn about unsafe vararg method decl. 246 * @param pos Position to be used for error reporting. 247 */ 248 void warnUnsafeVararg(DiagnosticPosition pos, String key, Object... args) { 249 if (lint.isEnabled(LintCategory.VARARGS) && allowSimplifiedVarargs) 250 log.warning(LintCategory.VARARGS, pos, key, args); 251 } 252 253 /** Warn about using proprietary API. 254 * @param pos Position to be used for error reporting. 255 * @param msg A string describing the problem. 256 */ 257 public void warnSunApi(DiagnosticPosition pos, String msg, Object... args) { 258 if (!lint.isSuppressed(LintCategory.SUNAPI)) 259 sunApiHandler.report(pos, msg, args); 260 } 261 262 public void warnStatic(DiagnosticPosition pos, String msg, Object... args) { 263 if (lint.isEnabled(LintCategory.STATIC)) 264 log.warning(LintCategory.STATIC, pos, msg, args); 265 } 266 267 /** 268 * Report any deferred diagnostics. 269 */ 270 public void reportDeferredDiagnostics() { 271 deprecationHandler.reportDeferredDiagnostic(); 272 uncheckedHandler.reportDeferredDiagnostic(); 273 sunApiHandler.reportDeferredDiagnostic(); 274 } 275 276 277 /** Report a failure to complete a class. 278 * @param pos Position to be used for error reporting. 279 * @param ex The failure to report. 280 */ 281 public Type completionError(DiagnosticPosition pos, CompletionFailure ex) { 282 log.error(JCDiagnostic.DiagnosticFlag.NON_DEFERRABLE, pos, "cant.access", ex.sym, ex.getDetailValue()); 283 if (ex instanceof ClassReader.BadClassFile 284 && !suppressAbortOnBadClassFile) throw new Abort(); 285 else return syms.errType; 286 } 287 288 /** Report an error that wrong type tag was found. 289 * @param pos Position to be used for error reporting. 290 * @param required An internationalized string describing the type tag 291 * required. 292 * @param found The type that was found. 293 */ 294 Type typeTagError(DiagnosticPosition pos, Object required, Object found) { 295 // this error used to be raised by the parser, 296 // but has been delayed to this point: 297 if (found instanceof Type && ((Type)found).hasTag(VOID)) { 298 log.error(pos, "illegal.start.of.type"); 299 return syms.errType; 300 } 301 log.error(pos, "type.found.req", found, required); 302 return types.createErrorType(found instanceof Type ? (Type)found : syms.errType); 303 } 304 305 /** Report an error that symbol cannot be referenced before super 306 * has been called. 307 * @param pos Position to be used for error reporting. 308 * @param sym The referenced symbol. 309 */ 310 void earlyRefError(DiagnosticPosition pos, Symbol sym) { 311 log.error(pos, "cant.ref.before.ctor.called", sym); 312 } 313 314 /** Report duplicate declaration error. 315 */ 316 void duplicateError(DiagnosticPosition pos, Symbol sym) { 317 if (!sym.type.isErroneous()) { 318 Symbol location = sym.location(); 319 if (location.kind == MTH && 320 ((MethodSymbol)location).isStaticOrInstanceInit()) { 321 log.error(pos, "already.defined.in.clinit", kindName(sym), sym, 322 kindName(sym.location()), kindName(sym.location().enclClass()), 323 sym.location().enclClass()); 324 } else { 325 log.error(pos, "already.defined", kindName(sym), sym, 326 kindName(sym.location()), sym.location()); 327 } 328 } 329 } 330 331 /** Report array/varargs duplicate declaration 332 */ 333 void varargsDuplicateError(DiagnosticPosition pos, Symbol sym1, Symbol sym2) { 334 if (!sym1.type.isErroneous() && !sym2.type.isErroneous()) { 335 log.error(pos, "array.and.varargs", sym1, sym2, sym2.location()); 336 } 337 } 338 339 /* ************************************************************************ 340 * duplicate declaration checking 341 *************************************************************************/ 342 343 /** Check that variable does not hide variable with same name in 344 * immediately enclosing local scope. 345 * @param pos Position for error reporting. 346 * @param v The symbol. 347 * @param s The scope. 348 */ 349 void checkTransparentVar(DiagnosticPosition pos, VarSymbol v, Scope s) { 350 if (s.next != null) { 351 for (Scope.Entry e = s.next.lookup(v.name); 352 e.scope != null && e.sym.owner == v.owner; 353 e = e.next()) { 354 if (e.sym.kind == VAR && 355 (e.sym.owner.kind & (VAR | MTH)) != 0 && 356 v.name != names.error) { 357 duplicateError(pos, e.sym); 358 return; 359 } 360 } 361 } 362 } 363 364 /** Check that a class or interface does not hide a class or 365 * interface with same name in immediately enclosing local scope. 366 * @param pos Position for error reporting. 367 * @param c The symbol. 368 * @param s The scope. 369 */ 370 void checkTransparentClass(DiagnosticPosition pos, ClassSymbol c, Scope s) { 371 if (s.next != null) { 372 for (Scope.Entry e = s.next.lookup(c.name); 373 e.scope != null && e.sym.owner == c.owner; 374 e = e.next()) { 375 if (e.sym.kind == TYP && !e.sym.type.hasTag(TYPEVAR) && 376 (e.sym.owner.kind & (VAR | MTH)) != 0 && 377 c.name != names.error) { 378 duplicateError(pos, e.sym); 379 return; 380 } 381 } 382 } 383 } 384 385 /** Check that class does not have the same name as one of 386 * its enclosing classes, or as a class defined in its enclosing scope. 387 * return true if class is unique in its enclosing scope. 388 * @param pos Position for error reporting. 389 * @param name The class name. 390 * @param s The enclosing scope. 391 */ 392 boolean checkUniqueClassName(DiagnosticPosition pos, Name name, Scope s) { 393 for (Scope.Entry e = s.lookup(name); e.scope == s; e = e.next()) { 394 if (e.sym.kind == TYP && e.sym.name != names.error) { 395 duplicateError(pos, e.sym); 396 return false; 397 } 398 } 399 for (Symbol sym = s.owner; sym != null; sym = sym.owner) { 400 if (sym.kind == TYP && sym.name == name && sym.name != names.error) { 401 duplicateError(pos, sym); 402 return true; 403 } 404 } 405 return true; 406 } 407 408 /* ************************************************************************* 409 * Class name generation 410 **************************************************************************/ 411 412 /** Return name of local class. 413 * This is of the form {@code <enclClass> $ n <classname> } 414 * where 415 * enclClass is the flat name of the enclosing class, 416 * classname is the simple name of the local class 417 */ 418 Name localClassName(ClassSymbol c) { 419 for (int i=1; ; i++) { 420 Name flatname = names. 421 fromString("" + c.owner.enclClass().flatname + 422 syntheticNameChar + i + 423 c.name); 424 if (compiled.get(flatname) == null) return flatname; 425 } 426 } 427 428 /* ************************************************************************* 429 * Type Checking 430 **************************************************************************/ 431 432 /** 433 * A check context is an object that can be used to perform compatibility 434 * checks - depending on the check context, meaning of 'compatibility' might 435 * vary significantly. 436 */ 437 public interface CheckContext { 438 /** 439 * Is type 'found' compatible with type 'req' in given context 440 */ 441 boolean compatible(Type found, Type req, Warner warn); 442 /** 443 * Report a check error 444 */ 445 void report(DiagnosticPosition pos, JCDiagnostic details); 446 /** 447 * Obtain a warner for this check context 448 */ 449 public Warner checkWarner(DiagnosticPosition pos, Type found, Type req); 450 451 public Infer.InferenceContext inferenceContext(); 452 453 public DeferredAttr.DeferredAttrContext deferredAttrContext(); 454 } 455 456 /** 457 * This class represent a check context that is nested within another check 458 * context - useful to check sub-expressions. The default behavior simply 459 * redirects all method calls to the enclosing check context leveraging 460 * the forwarding pattern. 461 */ 462 static class NestedCheckContext implements CheckContext { 463 CheckContext enclosingContext; 464 465 NestedCheckContext(CheckContext enclosingContext) { 466 this.enclosingContext = enclosingContext; 467 } 468 469 public boolean compatible(Type found, Type req, Warner warn) { 470 return enclosingContext.compatible(found, req, warn); 471 } 472 473 public void report(DiagnosticPosition pos, JCDiagnostic details) { 474 enclosingContext.report(pos, details); 475 } 476 477 public Warner checkWarner(DiagnosticPosition pos, Type found, Type req) { 478 return enclosingContext.checkWarner(pos, found, req); 479 } 480 481 public Infer.InferenceContext inferenceContext() { 482 return enclosingContext.inferenceContext(); 483 } 484 485 public DeferredAttrContext deferredAttrContext() { 486 return enclosingContext.deferredAttrContext(); 487 } 488 } 489 490 /** 491 * Check context to be used when evaluating assignment/return statements 492 */ 493 CheckContext basicHandler = new CheckContext() { 494 public void report(DiagnosticPosition pos, JCDiagnostic details) { 495 log.error(pos, "prob.found.req", details); 496 } 497 public boolean compatible(Type found, Type req, Warner warn) { 498 return types.isAssignable(found, req, warn); 499 } 500 501 public Warner checkWarner(DiagnosticPosition pos, Type found, Type req) { 502 return convertWarner(pos, found, req); 503 } 504 505 public InferenceContext inferenceContext() { 506 return infer.emptyContext; 507 } 508 509 public DeferredAttrContext deferredAttrContext() { 510 return deferredAttr.emptyDeferredAttrContext; 511 } 512 }; 513 514 /** Check that a given type is assignable to a given proto-type. 515 * If it is, return the type, otherwise return errType. 516 * @param pos Position to be used for error reporting. 517 * @param found The type that was found. 518 * @param req The type that was required. 519 */ 520 Type checkType(DiagnosticPosition pos, Type found, Type req) { 521 return checkType(pos, found, req, basicHandler); 522 } 523 524 Type checkType(final DiagnosticPosition pos, final Type found, final Type req, final CheckContext checkContext) { 525 final Infer.InferenceContext inferenceContext = checkContext.inferenceContext(); 526 if (inferenceContext.free(req)) { 527 inferenceContext.addFreeTypeListener(List.of(req), new FreeTypeListener() { 528 @Override 529 public void typesInferred(InferenceContext inferenceContext) { 530 checkType(pos, found, inferenceContext.asInstType(req), checkContext); 531 } 532 }); 533 } 534 if (req.hasTag(ERROR)) 535 return req; 536 if (req.hasTag(NONE)) 537 return found; 538 if (checkContext.compatible(found, req, checkContext.checkWarner(pos, found, req))) { 539 return found; 540 } else { 541 if (found.isNumeric() && req.isNumeric()) { 542 checkContext.report(pos, diags.fragment("possible.loss.of.precision", found, req)); 543 return types.createErrorType(found); 544 } 545 checkContext.report(pos, diags.fragment("inconvertible.types", found, req)); 546 return types.createErrorType(found); 547 } 548 } 549 550 /** Check that a given type can be cast to a given target type. 551 * Return the result of the cast. 552 * @param pos Position to be used for error reporting. 553 * @param found The type that is being cast. 554 * @param req The target type of the cast. 555 */ 556 Type checkCastable(DiagnosticPosition pos, Type found, Type req) { 557 return checkCastable(pos, found, req, basicHandler); 558 } 559 Type checkCastable(DiagnosticPosition pos, Type found, Type req, CheckContext checkContext) { 560 if (types.isCastable(found, req, castWarner(pos, found, req))) { 561 return req; 562 } else { 563 checkContext.report(pos, diags.fragment("inconvertible.types", found, req)); 564 return types.createErrorType(found); 565 } 566 } 567 568 /** Check for redundant casts (i.e. where source type is a subtype of target type) 569 * The problem should only be reported for non-292 cast 570 */ 571 public void checkRedundantCast(Env<AttrContext> env, final JCTypeCast tree) { 572 if (!tree.type.isErroneous() 573 && types.isSameType(tree.expr.type, tree.clazz.type) 574 && !(ignoreAnnotatedCasts && TreeInfo.containsTypeAnnotation(tree.clazz)) 575 && !is292targetTypeCast(tree)) { 576 deferredLintHandler.report(new DeferredLintHandler.LintLogger() { 577 @Override 578 public void report() { 579 if (lint.isEnabled(Lint.LintCategory.CAST)) 580 log.warning(Lint.LintCategory.CAST, 581 tree.pos(), "redundant.cast", tree.expr.type); 582 } 583 }); 584 } 585 } 586 //where 587 private boolean is292targetTypeCast(JCTypeCast tree) { 588 boolean is292targetTypeCast = false; 589 JCExpression expr = TreeInfo.skipParens(tree.expr); 590 if (expr.hasTag(APPLY)) { 591 JCMethodInvocation apply = (JCMethodInvocation)expr; 592 Symbol sym = TreeInfo.symbol(apply.meth); 593 is292targetTypeCast = sym != null && 594 sym.kind == MTH && 595 (sym.flags() & HYPOTHETICAL) != 0; 596 } 597 return is292targetTypeCast; 598 } 599 600 private static final boolean ignoreAnnotatedCasts = true; 601 602 /** Check that a type is within some bounds. 603 * 604 * Used in TypeApply to verify that, e.g., X in {@code V<X>} is a valid 605 * type argument. 606 * @param a The type that should be bounded by bs. 607 * @param bound The bound. 608 */ 609 private boolean checkExtends(Type a, Type bound) { 610 if (a.isUnbound()) { 611 return true; 612 } else if (!a.hasTag(WILDCARD)) { 613 a = types.upperBound(a); 614 return types.isSubtype(a, bound); 615 } else if (a.isExtendsBound()) { 616 return types.isCastable(bound, types.upperBound(a), types.noWarnings); 617 } else if (a.isSuperBound()) { 618 return !types.notSoftSubtype(types.lowerBound(a), bound); 619 } 620 return true; 621 } 622 623 /** Check that type is different from 'void'. 624 * @param pos Position to be used for error reporting. 625 * @param t The type to be checked. 626 */ 627 Type checkNonVoid(DiagnosticPosition pos, Type t) { 628 if (t.hasTag(VOID)) { 629 log.error(pos, "void.not.allowed.here"); 630 return types.createErrorType(t); 631 } else { 632 return t; 633 } 634 } 635 636 Type checkClassOrArrayType(DiagnosticPosition pos, Type t) { 637 if (!t.hasTag(CLASS) && !t.hasTag(ARRAY) && !t.hasTag(ERROR)) { 638 return typeTagError(pos, 639 diags.fragment("type.req.class.array"), 640 asTypeParam(t)); 641 } else { 642 return t; 643 } 644 } 645 646 /** Check that type is a class or interface type. 647 * @param pos Position to be used for error reporting. 648 * @param t The type to be checked. 649 */ 650 Type checkClassType(DiagnosticPosition pos, Type t) { 651 if (!t.hasTag(CLASS) && !t.hasTag(ERROR)) { 652 return typeTagError(pos, 653 diags.fragment("type.req.class"), 654 asTypeParam(t)); 655 } else { 656 return t; 657 } 658 } 659 //where 660 private Object asTypeParam(Type t) { 661 return (t.hasTag(TYPEVAR)) 662 ? diags.fragment("type.parameter", t) 663 : t; 664 } 665 666 /** Check that type is a valid qualifier for a constructor reference expression 667 */ 668 Type checkConstructorRefType(DiagnosticPosition pos, Type t) { 669 t = checkClassOrArrayType(pos, t); 670 if (t.hasTag(CLASS)) { 671 if ((t.tsym.flags() & (ABSTRACT | INTERFACE)) != 0) { 672 log.error(pos, "abstract.cant.be.instantiated", t.tsym); 673 t = types.createErrorType(t); 674 } else if ((t.tsym.flags() & ENUM) != 0) { 675 log.error(pos, "enum.cant.be.instantiated"); 676 t = types.createErrorType(t); 677 } else { 678 t = checkClassType(pos, t, true); 679 } 680 } else if (t.hasTag(ARRAY)) { 681 if (!types.isReifiable(((ArrayType)t).elemtype)) { 682 log.error(pos, "generic.array.creation"); 683 t = types.createErrorType(t); 684 } 685 } 686 return t; 687 } 688 689 /** Check that type is a class or interface type. 690 * @param pos Position to be used for error reporting. 691 * @param t The type to be checked. 692 * @param noBounds True if type bounds are illegal here. 693 */ 694 Type checkClassType(DiagnosticPosition pos, Type t, boolean noBounds) { 695 t = checkClassType(pos, t); 696 if (noBounds && t.isParameterized()) { 697 List<Type> args = t.getTypeArguments(); 698 while (args.nonEmpty()) { 699 if (args.head.hasTag(WILDCARD)) 700 return typeTagError(pos, 701 diags.fragment("type.req.exact"), 702 args.head); 703 args = args.tail; 704 } 705 } 706 return t; 707 } 708 709 // Analog of checkClassType that calls checkClassOrArrayType instead 710 Type checkClassOrArrayType(DiagnosticPosition pos, 711 Type t, boolean noBounds) { 712 t = checkClassOrArrayType(pos, t); 713 if (noBounds && t.isParameterized()) { 714 List<Type> args = t.getTypeArguments(); 715 while (args.nonEmpty()) { 716 if (args.head.hasTag(WILDCARD)) 717 return typeTagError(pos, 718 diags.fragment("type.req.exact"), 719 args.head); 720 args = args.tail; 721 } 722 } 723 return t; 724 } 725 726 /** Check that type is a reifiable class, interface or array type. 727 * @param pos Position to be used for error reporting. 728 * @param t The type to be checked. 729 */ 730 Type checkReifiableReferenceType(DiagnosticPosition pos, Type t) { 731 t = checkClassOrArrayType(pos, t); 732 if (!t.isErroneous() && !types.isReifiable(t)) { 733 log.error(pos, "illegal.generic.type.for.instof"); 734 return types.createErrorType(t); 735 } else { 736 return t; 737 } 738 } 739 740 /** Check that type is a reference type, i.e. a class, interface or array type 741 * or a type variable. 742 * @param pos Position to be used for error reporting. 743 * @param t The type to be checked. 744 */ 745 Type checkRefType(DiagnosticPosition pos, Type t) { 746 if (t.isReference()) 747 return t; 748 else 749 return typeTagError(pos, 750 diags.fragment("type.req.ref"), 751 t); 752 } 753 754 /** Check that each type is a reference type, i.e. a class, interface or array type 755 * or a type variable. 756 * @param trees Original trees, used for error reporting. 757 * @param types The types to be checked. 758 */ 759 List<Type> checkRefTypes(List<JCExpression> trees, List<Type> types) { 760 List<JCExpression> tl = trees; 761 for (List<Type> l = types; l.nonEmpty(); l = l.tail) { 762 l.head = checkRefType(tl.head.pos(), l.head); 763 tl = tl.tail; 764 } 765 return types; 766 } 767 768 /** Check that type is a null or reference type. 769 * @param pos Position to be used for error reporting. 770 * @param t The type to be checked. 771 */ 772 Type checkNullOrRefType(DiagnosticPosition pos, Type t) { 773 if (t.isReference() || t.hasTag(BOT)) 774 return t; 775 else 776 return typeTagError(pos, 777 diags.fragment("type.req.ref"), 778 t); 779 } 780 781 /** Check that flag set does not contain elements of two conflicting sets. s 782 * Return true if it doesn't. 783 * @param pos Position to be used for error reporting. 784 * @param flags The set of flags to be checked. 785 * @param set1 Conflicting flags set #1. 786 * @param set2 Conflicting flags set #2. 787 */ 788 boolean checkDisjoint(DiagnosticPosition pos, long flags, long set1, long set2) { 789 if ((flags & set1) != 0 && (flags & set2) != 0) { 790 log.error(pos, 791 "illegal.combination.of.modifiers", 792 asFlagSet(TreeInfo.firstFlag(flags & set1)), 793 asFlagSet(TreeInfo.firstFlag(flags & set2))); 794 return false; 795 } else 796 return true; 797 } 798 799 /** Check that usage of diamond operator is correct (i.e. diamond should not 800 * be used with non-generic classes or in anonymous class creation expressions) 801 */ 802 Type checkDiamond(JCNewClass tree, Type t) { 803 if (!TreeInfo.isDiamond(tree) || 804 t.isErroneous()) { 805 return checkClassType(tree.clazz.pos(), t, true); 806 } else if (tree.def != null) { 807 log.error(tree.clazz.pos(), 808 "cant.apply.diamond.1", 809 t, diags.fragment("diamond.and.anon.class", t)); 810 return types.createErrorType(t); 811 } else if (t.tsym.type.getTypeArguments().isEmpty()) { 812 log.error(tree.clazz.pos(), 813 "cant.apply.diamond.1", 814 t, diags.fragment("diamond.non.generic", t)); 815 return types.createErrorType(t); 816 } else if (tree.typeargs != null && 817 tree.typeargs.nonEmpty()) { 818 log.error(tree.clazz.pos(), 819 "cant.apply.diamond.1", 820 t, diags.fragment("diamond.and.explicit.params", t)); 821 return types.createErrorType(t); 822 } else { 823 return t; 824 } 825 } 826 827 void checkVarargsMethodDecl(Env<AttrContext> env, JCMethodDecl tree) { 828 MethodSymbol m = tree.sym; 829 if (!allowSimplifiedVarargs) return; 830 boolean hasTrustMeAnno = m.attribute(syms.trustMeType.tsym) != null; 831 Type varargElemType = null; 832 if (m.isVarArgs()) { 833 varargElemType = types.elemtype(tree.params.last().type); 834 } 835 if (hasTrustMeAnno && !isTrustMeAllowedOnMethod(m)) { 836 if (varargElemType != null) { 837 log.error(tree, 838 "varargs.invalid.trustme.anno", 839 syms.trustMeType.tsym, 840 diags.fragment("varargs.trustme.on.virtual.varargs", m)); 841 } else { 842 log.error(tree, 843 "varargs.invalid.trustme.anno", 844 syms.trustMeType.tsym, 845 diags.fragment("varargs.trustme.on.non.varargs.meth", m)); 846 } 847 } else if (hasTrustMeAnno && varargElemType != null && 848 types.isReifiable(varargElemType)) { 849 warnUnsafeVararg(tree, 850 "varargs.redundant.trustme.anno", 851 syms.trustMeType.tsym, 852 diags.fragment("varargs.trustme.on.reifiable.varargs", varargElemType)); 853 } 854 else if (!hasTrustMeAnno && varargElemType != null && 855 !types.isReifiable(varargElemType)) { 856 warnUnchecked(tree.params.head.pos(), "unchecked.varargs.non.reifiable.type", varargElemType); 857 } 858 } 859 //where 860 private boolean isTrustMeAllowedOnMethod(Symbol s) { 861 return (s.flags() & VARARGS) != 0 && 862 (s.isConstructor() || 863 (s.flags() & (STATIC | FINAL)) != 0); 864 } 865 866 Type checkMethod(final Type mtype, 867 final Symbol sym, 868 final Env<AttrContext> env, 869 final List<JCExpression> argtrees, 870 final List<Type> argtypes, 871 final boolean useVarargs, 872 InferenceContext inferenceContext) { 873 // System.out.println("call : " + env.tree); 874 // System.out.println("method : " + owntype); 875 // System.out.println("actuals: " + argtypes); 876 if (inferenceContext.free(mtype)) { 877 inferenceContext.addFreeTypeListener(List.of(mtype), new FreeTypeListener() { 878 public void typesInferred(InferenceContext inferenceContext) { 879 checkMethod(inferenceContext.asInstType(mtype), sym, env, argtrees, argtypes, useVarargs, inferenceContext); 880 } 881 }); 882 return mtype; 883 } 884 Type owntype = mtype; 885 List<Type> formals = owntype.getParameterTypes(); 886 List<Type> nonInferred = sym.type.getParameterTypes(); 887 if (nonInferred.length() != formals.length()) nonInferred = formals; 888 Type last = useVarargs ? formals.last() : null; 889 if (sym.name == names.init && sym.owner == syms.enumSym) { 890 formals = formals.tail.tail; 891 nonInferred = nonInferred.tail.tail; 892 } 893 List<JCExpression> args = argtrees; 894 if (args != null) { 895 //this is null when type-checking a method reference 896 while (formals.head != last) { 897 JCTree arg = args.head; 898 Warner warn = convertWarner(arg.pos(), arg.type, nonInferred.head); 899 assertConvertible(arg, arg.type, formals.head, warn); 900 args = args.tail; 901 formals = formals.tail; 902 nonInferred = nonInferred.tail; 903 } 904 if (useVarargs) { 905 Type varArg = types.elemtype(last); 906 while (args.tail != null) { 907 JCTree arg = args.head; 908 Warner warn = convertWarner(arg.pos(), arg.type, varArg); 909 assertConvertible(arg, arg.type, varArg, warn); 910 args = args.tail; 911 } 912 } else if ((sym.flags() & (VARARGS | SIGNATURE_POLYMORPHIC)) == VARARGS && 913 allowVarargs) { 914 // non-varargs call to varargs method 915 Type varParam = owntype.getParameterTypes().last(); 916 Type lastArg = argtypes.last(); 917 if (types.isSubtypeUnchecked(lastArg, types.elemtype(varParam)) && 918 !types.isSameType(types.erasure(varParam), types.erasure(lastArg))) 919 log.warning(argtrees.last().pos(), "inexact.non-varargs.call", 920 types.elemtype(varParam), varParam); 921 } 922 } 923 if (useVarargs) { 924 Type argtype = owntype.getParameterTypes().last(); 925 if (!types.isReifiable(argtype) && 926 (!allowSimplifiedVarargs || 927 sym.attribute(syms.trustMeType.tsym) == null || 928 !isTrustMeAllowedOnMethod(sym))) { 929 warnUnchecked(env.tree.pos(), 930 "unchecked.generic.array.creation", 931 argtype); 932 } 933 if ((sym.baseSymbol().flags() & SIGNATURE_POLYMORPHIC) == 0) { 934 TreeInfo.setVarargsElement(env.tree, types.elemtype(argtype)); 935 } 936 } 937 PolyKind pkind = (sym.type.hasTag(FORALL) && 938 sym.type.getReturnType().containsAny(((ForAll)sym.type).tvars)) ? 939 PolyKind.POLY : PolyKind.STANDALONE; 940 TreeInfo.setPolyKind(env.tree, pkind); 941 return owntype; 942 } 943 //where 944 private void assertConvertible(JCTree tree, Type actual, Type formal, Warner warn) { 945 if (types.isConvertible(actual, formal, warn)) 946 return; 947 948 if (formal.isCompound() 949 && types.isSubtype(actual, types.supertype(formal)) 950 && types.isSubtypeUnchecked(actual, types.interfaces(formal), warn)) 951 return; 952 } 953 954 /** 955 * Check that type 't' is a valid instantiation of a generic class 956 * (see JLS 4.5) 957 * 958 * @param t class type to be checked 959 * @return true if 't' is well-formed 960 */ 961 public boolean checkValidGenericType(Type t) { 962 return firstIncompatibleTypeArg(t) == null; 963 } 964 //WHERE 965 private Type firstIncompatibleTypeArg(Type type) { 966 List<Type> formals = type.tsym.type.allparams(); 967 List<Type> actuals = type.allparams(); 968 List<Type> args = type.getTypeArguments(); 969 List<Type> forms = type.tsym.type.getTypeArguments(); 970 ListBuffer<Type> bounds_buf = new ListBuffer<Type>(); 971 972 // For matching pairs of actual argument types `a' and 973 // formal type parameters with declared bound `b' ... 974 while (args.nonEmpty() && forms.nonEmpty()) { 975 // exact type arguments needs to know their 976 // bounds (for upper and lower bound 977 // calculations). So we create new bounds where 978 // type-parameters are replaced with actuals argument types. 979 bounds_buf.append(types.subst(forms.head.getUpperBound(), formals, actuals)); 980 args = args.tail; 981 forms = forms.tail; 982 } 983 984 args = type.getTypeArguments(); 985 List<Type> tvars_cap = types.substBounds(formals, 986 formals, 987 types.capture(type).allparams()); 988 while (args.nonEmpty() && tvars_cap.nonEmpty()) { 989 // Let the actual arguments know their bound 990 args.head.withTypeVar((TypeVar)tvars_cap.head); 991 args = args.tail; 992 tvars_cap = tvars_cap.tail; 993 } 994 995 args = type.getTypeArguments(); 996 List<Type> bounds = bounds_buf.toList(); 997 998 while (args.nonEmpty() && bounds.nonEmpty()) { 999 Type actual = args.head; 1000 if (!isTypeArgErroneous(actual) && 1001 !bounds.head.isErroneous() && 1002 !checkExtends(actual, bounds.head)) { 1003 return args.head; 1004 } 1005 args = args.tail; 1006 bounds = bounds.tail; 1007 } 1008 1009 args = type.getTypeArguments(); 1010 bounds = bounds_buf.toList(); 1011 1012 for (Type arg : types.capture(type).getTypeArguments()) { 1013 if (arg.hasTag(TYPEVAR) && 1014 arg.getUpperBound().isErroneous() && 1015 !bounds.head.isErroneous() && 1016 !isTypeArgErroneous(args.head)) { 1017 return args.head; 1018 } 1019 bounds = bounds.tail; 1020 args = args.tail; 1021 } 1022 1023 return null; 1024 } 1025 //where 1026 boolean isTypeArgErroneous(Type t) { 1027 return isTypeArgErroneous.visit(t); 1028 } 1029 1030 Types.UnaryVisitor<Boolean> isTypeArgErroneous = new Types.UnaryVisitor<Boolean>() { 1031 public Boolean visitType(Type t, Void s) { 1032 return t.isErroneous(); 1033 } 1034 @Override 1035 public Boolean visitTypeVar(TypeVar t, Void s) { 1036 return visit(t.getUpperBound()); 1037 } 1038 @Override 1039 public Boolean visitCapturedType(CapturedType t, Void s) { 1040 return visit(t.getUpperBound()) || 1041 visit(t.getLowerBound()); 1042 } 1043 @Override 1044 public Boolean visitWildcardType(WildcardType t, Void s) { 1045 return visit(t.type); 1046 } 1047 }; 1048 1049 /** Check that given modifiers are legal for given symbol and 1050 * return modifiers together with any implicit modifiers for that symbol. 1051 * Warning: we can't use flags() here since this method 1052 * is called during class enter, when flags() would cause a premature 1053 * completion. 1054 * @param pos Position to be used for error reporting. 1055 * @param flags The set of modifiers given in a definition. 1056 * @param sym The defined symbol. 1057 */ 1058 long checkFlags(DiagnosticPosition pos, long flags, Symbol sym, JCTree tree) { 1059 long mask; 1060 long implicit = 0; 1061 1062 switch (sym.kind) { 1063 case VAR: 1064 if (sym.owner.kind != TYP) 1065 mask = LocalVarFlags; 1066 else if ((sym.owner.flags_field & INTERFACE) != 0) 1067 mask = implicit = InterfaceVarFlags; 1068 else 1069 mask = VarFlags; 1070 break; 1071 case MTH: 1072 if (sym.name == names.init) { 1073 if ((sym.owner.flags_field & ENUM) != 0) { 1074 // enum constructors cannot be declared public or 1075 // protected and must be implicitly or explicitly 1076 // private 1077 implicit = PRIVATE; 1078 mask = PRIVATE; 1079 } else 1080 mask = ConstructorFlags; 1081 } else if ((sym.owner.flags_field & INTERFACE) != 0) { 1082 if ((sym.owner.flags_field & ANNOTATION) != 0) { 1083 mask = AnnotationTypeElementMask; 1084 implicit = PUBLIC | ABSTRACT; 1085 } else if ((flags & (DEFAULT | STATIC)) != 0) { 1086 mask = InterfaceMethodMask; 1087 implicit = PUBLIC; 1088 if ((flags & DEFAULT) != 0) { 1089 implicit |= ABSTRACT; 1090 } 1091 } else { 1092 mask = implicit = InterfaceMethodFlags; 1093 } 1094 } else { 1095 mask = MethodFlags; 1096 } 1097 // Imply STRICTFP if owner has STRICTFP set. 1098 if (((flags|implicit) & Flags.ABSTRACT) == 0 || 1099 ((flags) & Flags.DEFAULT) != 0) 1100 implicit |= sym.owner.flags_field & STRICTFP; 1101 break; 1102 case TYP: 1103 if (sym.isLocal()) { 1104 mask = LocalClassFlags; 1105 if (sym.name.isEmpty()) { // Anonymous class 1106 // Anonymous classes in static methods are themselves static; 1107 // that's why we admit STATIC here. 1108 mask |= STATIC; 1109 // JLS: Anonymous classes are final. 1110 implicit |= FINAL; 1111 } 1112 if ((sym.owner.flags_field & STATIC) == 0 && 1113 (flags & ENUM) != 0) 1114 log.error(pos, "enums.must.be.static"); 1115 } else if (sym.owner.kind == TYP) { 1116 mask = MemberClassFlags; 1117 if (sym.owner.owner.kind == PCK || 1118 (sym.owner.flags_field & STATIC) != 0) 1119 mask |= STATIC; 1120 else if ((flags & ENUM) != 0) 1121 log.error(pos, "enums.must.be.static"); 1122 // Nested interfaces and enums are always STATIC (Spec ???) 1123 if ((flags & (INTERFACE | ENUM)) != 0 ) implicit = STATIC; 1124 } else { 1125 mask = ClassFlags; 1126 } 1127 // Interfaces are always ABSTRACT 1128 if ((flags & INTERFACE) != 0) implicit |= ABSTRACT; 1129 1130 if ((flags & ENUM) != 0) { 1131 // enums can't be declared abstract or final 1132 mask &= ~(ABSTRACT | FINAL); 1133 implicit |= implicitEnumFinalFlag(tree); 1134 } 1135 // Imply STRICTFP if owner has STRICTFP set. 1136 implicit |= sym.owner.flags_field & STRICTFP; 1137 break; 1138 default: 1139 throw new AssertionError(); 1140 } 1141 long illegal = flags & ExtendedStandardFlags & ~mask; 1142 if (illegal != 0) { 1143 if ((illegal & INTERFACE) != 0) { 1144 log.error(pos, "intf.not.allowed.here"); 1145 mask |= INTERFACE; 1146 } 1147 else { 1148 log.error(pos, 1149 "mod.not.allowed.here", asFlagSet(illegal)); 1150 } 1151 } 1152 else if ((sym.kind == TYP || 1153 // ISSUE: Disallowing abstract&private is no longer appropriate 1154 // in the presence of inner classes. Should it be deleted here? 1155 checkDisjoint(pos, flags, 1156 ABSTRACT, 1157 PRIVATE | STATIC | DEFAULT)) 1158 && 1159 checkDisjoint(pos, flags, 1160 STATIC, 1161 DEFAULT) 1162 && 1163 checkDisjoint(pos, flags, 1164 ABSTRACT | INTERFACE, 1165 FINAL | NATIVE | SYNCHRONIZED) 1166 && 1167 checkDisjoint(pos, flags, 1168 PUBLIC, 1169 PRIVATE | PROTECTED) 1170 && 1171 checkDisjoint(pos, flags, 1172 PRIVATE, 1173 PUBLIC | PROTECTED) 1174 && 1175 checkDisjoint(pos, flags, 1176 FINAL, 1177 VOLATILE) 1178 && 1179 (sym.kind == TYP || 1180 checkDisjoint(pos, flags, 1181 ABSTRACT | NATIVE, 1182 STRICTFP))) { 1183 // skip 1184 } 1185 return flags & (mask | ~ExtendedStandardFlags) | implicit; 1186 } 1187 1188 1189 /** Determine if this enum should be implicitly final. 1190 * 1191 * If the enum has no specialized enum contants, it is final. 1192 * 1193 * If the enum does have specialized enum contants, it is 1194 * <i>not</i> final. 1195 */ 1196 private long implicitEnumFinalFlag(JCTree tree) { 1197 if (!tree.hasTag(CLASSDEF)) return 0; 1198 class SpecialTreeVisitor extends JCTree.Visitor { 1199 boolean specialized; 1200 SpecialTreeVisitor() { 1201 this.specialized = false; 1202 }; 1203 1204 @Override 1205 public void visitTree(JCTree tree) { /* no-op */ } 1206 1207 @Override 1208 public void visitVarDef(JCVariableDecl tree) { 1209 if ((tree.mods.flags & ENUM) != 0) { 1210 if (tree.init instanceof JCNewClass && 1211 ((JCNewClass) tree.init).def != null) { 1212 specialized = true; 1213 } 1214 } 1215 } 1216 } 1217 1218 SpecialTreeVisitor sts = new SpecialTreeVisitor(); 1219 JCClassDecl cdef = (JCClassDecl) tree; 1220 for (JCTree defs: cdef.defs) { 1221 defs.accept(sts); 1222 if (sts.specialized) return 0; 1223 } 1224 return FINAL; 1225 } 1226 1227 /* ************************************************************************* 1228 * Type Validation 1229 **************************************************************************/ 1230 1231 /** Validate a type expression. That is, 1232 * check that all type arguments of a parametric type are within 1233 * their bounds. This must be done in a second phase after type attribution 1234 * since a class might have a subclass as type parameter bound. E.g: 1235 * 1236 * <pre>{@code 1237 * class B<A extends C> { ... } 1238 * class C extends B<C> { ... } 1239 * }</pre> 1240 * 1241 * and we can't make sure that the bound is already attributed because 1242 * of possible cycles. 1243 * 1244 * Visitor method: Validate a type expression, if it is not null, catching 1245 * and reporting any completion failures. 1246 */ 1247 void validate(JCTree tree, Env<AttrContext> env) { 1248 validate(tree, env, true); 1249 } 1250 void validate(JCTree tree, Env<AttrContext> env, boolean checkRaw) { 1251 new Validator(env).validateTree(tree, checkRaw, true); 1252 } 1253 1254 /** Visitor method: Validate a list of type expressions. 1255 */ 1256 void validate(List<? extends JCTree> trees, Env<AttrContext> env) { 1257 for (List<? extends JCTree> l = trees; l.nonEmpty(); l = l.tail) 1258 validate(l.head, env); 1259 } 1260 1261 /** A visitor class for type validation. 1262 */ 1263 class Validator extends JCTree.Visitor { 1264 1265 boolean checkRaw; 1266 boolean isOuter; 1267 Env<AttrContext> env; 1268 1269 Validator(Env<AttrContext> env) { 1270 this.env = env; 1271 } 1272 1273 @Override 1274 public void visitTypeArray(JCArrayTypeTree tree) { 1275 validateTree(tree.elemtype, checkRaw, isOuter); 1276 } 1277 1278 @Override 1279 public void visitTypeApply(JCTypeApply tree) { 1280 if (tree.type.hasTag(CLASS)) { 1281 List<JCExpression> args = tree.arguments; 1282 List<Type> forms = tree.type.tsym.type.getTypeArguments(); 1283 1284 Type incompatibleArg = firstIncompatibleTypeArg(tree.type); 1285 if (incompatibleArg != null) { 1286 for (JCTree arg : tree.arguments) { 1287 if (arg.type == incompatibleArg) { 1288 log.error(arg, "not.within.bounds", incompatibleArg, forms.head); 1289 } 1290 forms = forms.tail; 1291 } 1292 } 1293 1294 forms = tree.type.tsym.type.getTypeArguments(); 1295 1296 boolean is_java_lang_Class = tree.type.tsym.flatName() == names.java_lang_Class; 1297 1298 // For matching pairs of actual argument types `a' and 1299 // formal type parameters with declared bound `b' ... 1300 while (args.nonEmpty() && forms.nonEmpty()) { 1301 validateTree(args.head, 1302 !(isOuter && is_java_lang_Class), 1303 false); 1304 args = args.tail; 1305 forms = forms.tail; 1306 } 1307 1308 // Check that this type is either fully parameterized, or 1309 // not parameterized at all. 1310 if (tree.type.getEnclosingType().isRaw()) 1311 log.error(tree.pos(), "improperly.formed.type.inner.raw.param"); 1312 if (tree.clazz.hasTag(SELECT)) 1313 visitSelectInternal((JCFieldAccess)tree.clazz); 1314 } 1315 } 1316 1317 @Override 1318 public void visitTypeParameter(JCTypeParameter tree) { 1319 validateTrees(tree.bounds, true, isOuter); 1320 checkClassBounds(tree.pos(), tree.type); 1321 } 1322 1323 @Override 1324 public void visitWildcard(JCWildcard tree) { 1325 if (tree.inner != null) 1326 validateTree(tree.inner, true, isOuter); 1327 } 1328 1329 @Override 1330 public void visitSelect(JCFieldAccess tree) { 1331 if (tree.type.hasTag(CLASS)) { 1332 visitSelectInternal(tree); 1333 1334 // Check that this type is either fully parameterized, or 1335 // not parameterized at all. 1336 if (tree.selected.type.isParameterized() && tree.type.tsym.type.getTypeArguments().nonEmpty()) 1337 log.error(tree.pos(), "improperly.formed.type.param.missing"); 1338 } 1339 } 1340 1341 public void visitSelectInternal(JCFieldAccess tree) { 1342 if (tree.type.tsym.isStatic() && 1343 tree.selected.type.isParameterized()) { 1344 // The enclosing type is not a class, so we are 1345 // looking at a static member type. However, the 1346 // qualifying expression is parameterized. 1347 log.error(tree.pos(), "cant.select.static.class.from.param.type"); 1348 } else { 1349 // otherwise validate the rest of the expression 1350 tree.selected.accept(this); 1351 } 1352 } 1353 1354 @Override 1355 public void visitAnnotatedType(JCAnnotatedType tree) { 1356 tree.underlyingType.accept(this); 1357 } 1358 1359 /** Default visitor method: do nothing. 1360 */ 1361 @Override 1362 public void visitTree(JCTree tree) { 1363 } 1364 1365 public void validateTree(JCTree tree, boolean checkRaw, boolean isOuter) { 1366 if (tree != null) { 1367 boolean prevCheckRaw = this.checkRaw; 1368 this.checkRaw = checkRaw; 1369 this.isOuter = isOuter; 1370 1371 try { 1372 tree.accept(this); 1373 if (checkRaw) 1374 checkRaw(tree, env); 1375 } catch (CompletionFailure ex) { 1376 completionError(tree.pos(), ex); 1377 } finally { 1378 this.checkRaw = prevCheckRaw; 1379 } 1380 } 1381 } 1382 1383 public void validateTrees(List<? extends JCTree> trees, boolean checkRaw, boolean isOuter) { 1384 for (List<? extends JCTree> l = trees; l.nonEmpty(); l = l.tail) 1385 validateTree(l.head, checkRaw, isOuter); 1386 } 1387 } 1388 1389 void checkRaw(JCTree tree, Env<AttrContext> env) { 1390 if (lint.isEnabled(LintCategory.RAW) && 1391 tree.type.hasTag(CLASS) && 1392 !TreeInfo.isDiamond(tree) && 1393 !withinAnonConstr(env) && 1394 tree.type.isRaw()) { 1395 log.warning(LintCategory.RAW, 1396 tree.pos(), "raw.class.use", tree.type, tree.type.tsym.type); 1397 } 1398 } 1399 //where 1400 private boolean withinAnonConstr(Env<AttrContext> env) { 1401 return env.enclClass.name.isEmpty() && 1402 env.enclMethod != null && env.enclMethod.name == names.init; 1403 } 1404 1405 /* ************************************************************************* 1406 * Exception checking 1407 **************************************************************************/ 1408 1409 /* The following methods treat classes as sets that contain 1410 * the class itself and all their subclasses 1411 */ 1412 1413 /** Is given type a subtype of some of the types in given list? 1414 */ 1415 boolean subset(Type t, List<Type> ts) { 1416 for (List<Type> l = ts; l.nonEmpty(); l = l.tail) 1417 if (types.isSubtype(t, l.head)) return true; 1418 return false; 1419 } 1420 1421 /** Is given type a subtype or supertype of 1422 * some of the types in given list? 1423 */ 1424 boolean intersects(Type t, List<Type> ts) { 1425 for (List<Type> l = ts; l.nonEmpty(); l = l.tail) 1426 if (types.isSubtype(t, l.head) || types.isSubtype(l.head, t)) return true; 1427 return false; 1428 } 1429 1430 /** Add type set to given type list, unless it is a subclass of some class 1431 * in the list. 1432 */ 1433 List<Type> incl(Type t, List<Type> ts) { 1434 return subset(t, ts) ? ts : excl(t, ts).prepend(t); 1435 } 1436 1437 /** Remove type set from type set list. 1438 */ 1439 List<Type> excl(Type t, List<Type> ts) { 1440 if (ts.isEmpty()) { 1441 return ts; 1442 } else { 1443 List<Type> ts1 = excl(t, ts.tail); 1444 if (types.isSubtype(ts.head, t)) return ts1; 1445 else if (ts1 == ts.tail) return ts; 1446 else return ts1.prepend(ts.head); 1447 } 1448 } 1449 1450 /** Form the union of two type set lists. 1451 */ 1452 List<Type> union(List<Type> ts1, List<Type> ts2) { 1453 List<Type> ts = ts1; 1454 for (List<Type> l = ts2; l.nonEmpty(); l = l.tail) 1455 ts = incl(l.head, ts); 1456 return ts; 1457 } 1458 1459 /** Form the difference of two type lists. 1460 */ 1461 List<Type> diff(List<Type> ts1, List<Type> ts2) { 1462 List<Type> ts = ts1; 1463 for (List<Type> l = ts2; l.nonEmpty(); l = l.tail) 1464 ts = excl(l.head, ts); 1465 return ts; 1466 } 1467 1468 /** Form the intersection of two type lists. 1469 */ 1470 public List<Type> intersect(List<Type> ts1, List<Type> ts2) { 1471 List<Type> ts = List.nil(); 1472 for (List<Type> l = ts1; l.nonEmpty(); l = l.tail) 1473 if (subset(l.head, ts2)) ts = incl(l.head, ts); 1474 for (List<Type> l = ts2; l.nonEmpty(); l = l.tail) 1475 if (subset(l.head, ts1)) ts = incl(l.head, ts); 1476 return ts; 1477 } 1478 1479 /** Is exc an exception symbol that need not be declared? 1480 */ 1481 boolean isUnchecked(ClassSymbol exc) { 1482 return 1483 exc.kind == ERR || 1484 exc.isSubClass(syms.errorType.tsym, types) || 1485 exc.isSubClass(syms.runtimeExceptionType.tsym, types); 1486 } 1487 1488 /** Is exc an exception type that need not be declared? 1489 */ 1490 boolean isUnchecked(Type exc) { 1491 return 1492 (exc.hasTag(TYPEVAR)) ? isUnchecked(types.supertype(exc)) : 1493 (exc.hasTag(CLASS)) ? isUnchecked((ClassSymbol)exc.tsym) : 1494 exc.hasTag(BOT); 1495 } 1496 1497 /** Same, but handling completion failures. 1498 */ 1499 boolean isUnchecked(DiagnosticPosition pos, Type exc) { 1500 try { 1501 return isUnchecked(exc); 1502 } catch (CompletionFailure ex) { 1503 completionError(pos, ex); 1504 return true; 1505 } 1506 } 1507 1508 /** Is exc handled by given exception list? 1509 */ 1510 boolean isHandled(Type exc, List<Type> handled) { 1511 return isUnchecked(exc) || subset(exc, handled); 1512 } 1513 1514 /** Return all exceptions in thrown list that are not in handled list. 1515 * @param thrown The list of thrown exceptions. 1516 * @param handled The list of handled exceptions. 1517 */ 1518 List<Type> unhandled(List<Type> thrown, List<Type> handled) { 1519 List<Type> unhandled = List.nil(); 1520 for (List<Type> l = thrown; l.nonEmpty(); l = l.tail) 1521 if (!isHandled(l.head, handled)) unhandled = unhandled.prepend(l.head); 1522 return unhandled; 1523 } 1524 1525 /* ************************************************************************* 1526 * Overriding/Implementation checking 1527 **************************************************************************/ 1528 1529 /** The level of access protection given by a flag set, 1530 * where PRIVATE is highest and PUBLIC is lowest. 1531 */ 1532 static int protection(long flags) { 1533 switch ((short)(flags & AccessFlags)) { 1534 case PRIVATE: return 3; 1535 case PROTECTED: return 1; 1536 default: 1537 case PUBLIC: return 0; 1538 case 0: return 2; 1539 } 1540 } 1541 1542 /** A customized "cannot override" error message. 1543 * @param m The overriding method. 1544 * @param other The overridden method. 1545 * @return An internationalized string. 1546 */ 1547 Object cannotOverride(MethodSymbol m, MethodSymbol other) { 1548 String key; 1549 if ((other.owner.flags() & INTERFACE) == 0) 1550 key = "cant.override"; 1551 else if ((m.owner.flags() & INTERFACE) == 0) 1552 key = "cant.implement"; 1553 else 1554 key = "clashes.with"; 1555 return diags.fragment(key, m, m.location(), other, other.location()); 1556 } 1557 1558 /** A customized "override" warning message. 1559 * @param m The overriding method. 1560 * @param other The overridden method. 1561 * @return An internationalized string. 1562 */ 1563 Object uncheckedOverrides(MethodSymbol m, MethodSymbol other) { 1564 String key; 1565 if ((other.owner.flags() & INTERFACE) == 0) 1566 key = "unchecked.override"; 1567 else if ((m.owner.flags() & INTERFACE) == 0) 1568 key = "unchecked.implement"; 1569 else 1570 key = "unchecked.clash.with"; 1571 return diags.fragment(key, m, m.location(), other, other.location()); 1572 } 1573 1574 /** A customized "override" warning message. 1575 * @param m The overriding method. 1576 * @param other The overridden method. 1577 * @return An internationalized string. 1578 */ 1579 Object varargsOverrides(MethodSymbol m, MethodSymbol other) { 1580 String key; 1581 if ((other.owner.flags() & INTERFACE) == 0) 1582 key = "varargs.override"; 1583 else if ((m.owner.flags() & INTERFACE) == 0) 1584 key = "varargs.implement"; 1585 else 1586 key = "varargs.clash.with"; 1587 return diags.fragment(key, m, m.location(), other, other.location()); 1588 } 1589 1590 /** Check that this method conforms with overridden method 'other'. 1591 * where `origin' is the class where checking started. 1592 * Complications: 1593 * (1) Do not check overriding of synthetic methods 1594 * (reason: they might be final). 1595 * todo: check whether this is still necessary. 1596 * (2) Admit the case where an interface proxy throws fewer exceptions 1597 * than the method it implements. Augment the proxy methods with the 1598 * undeclared exceptions in this case. 1599 * (3) When generics are enabled, admit the case where an interface proxy 1600 * has a result type 1601 * extended by the result type of the method it implements. 1602 * Change the proxies result type to the smaller type in this case. 1603 * 1604 * @param tree The tree from which positions 1605 * are extracted for errors. 1606 * @param m The overriding method. 1607 * @param other The overridden method. 1608 * @param origin The class of which the overriding method 1609 * is a member. 1610 */ 1611 void checkOverride(JCTree tree, 1612 MethodSymbol m, 1613 MethodSymbol other, 1614 ClassSymbol origin) { 1615 // Don't check overriding of synthetic methods or by bridge methods. 1616 if ((m.flags() & (SYNTHETIC|BRIDGE)) != 0 || (other.flags() & SYNTHETIC) != 0) { 1617 return; 1618 } 1619 1620 // Error if static method overrides instance method (JLS 8.4.6.2). 1621 if ((m.flags() & STATIC) != 0 && 1622 (other.flags() & STATIC) == 0) { 1623 log.error(TreeInfo.diagnosticPositionFor(m, tree), "override.static", 1624 cannotOverride(m, other)); 1625 m.flags_field |= BAD_OVERRIDE; 1626 return; 1627 } 1628 1629 // Error if instance method overrides static or final 1630 // method (JLS 8.4.6.1). 1631 if ((other.flags() & FINAL) != 0 || 1632 (m.flags() & STATIC) == 0 && 1633 (other.flags() & STATIC) != 0) { 1634 log.error(TreeInfo.diagnosticPositionFor(m, tree), "override.meth", 1635 cannotOverride(m, other), 1636 asFlagSet(other.flags() & (FINAL | STATIC))); 1637 m.flags_field |= BAD_OVERRIDE; 1638 return; 1639 } 1640 1641 if ((m.owner.flags() & ANNOTATION) != 0) { 1642 // handled in validateAnnotationMethod 1643 return; 1644 } 1645 1646 // Error if overriding method has weaker access (JLS 8.4.6.3). 1647 if ((origin.flags() & INTERFACE) == 0 && 1648 protection(m.flags()) > protection(other.flags())) { 1649 log.error(TreeInfo.diagnosticPositionFor(m, tree), "override.weaker.access", 1650 cannotOverride(m, other), 1651 other.flags() == 0 ? 1652 "package" : 1653 asFlagSet(other.flags() & AccessFlags)); 1654 m.flags_field |= BAD_OVERRIDE; 1655 return; 1656 } 1657 1658 Type mt = types.memberType(origin.type, m); 1659 Type ot = types.memberType(origin.type, other); 1660 // Error if overriding result type is different 1661 // (or, in the case of generics mode, not a subtype) of 1662 // overridden result type. We have to rename any type parameters 1663 // before comparing types. 1664 List<Type> mtvars = mt.getTypeArguments(); 1665 List<Type> otvars = ot.getTypeArguments(); 1666 Type mtres = mt.getReturnType(); 1667 Type otres = types.subst(ot.getReturnType(), otvars, mtvars); 1668 1669 overrideWarner.clear(); 1670 boolean resultTypesOK = 1671 types.returnTypeSubstitutable(mt, ot, otres, overrideWarner); 1672 if (!resultTypesOK) { 1673 if (!allowCovariantReturns && 1674 m.owner != origin && 1675 m.owner.isSubClass(other.owner, types)) { 1676 // allow limited interoperability with covariant returns 1677 } else { 1678 log.error(TreeInfo.diagnosticPositionFor(m, tree), 1679 "override.incompatible.ret", 1680 cannotOverride(m, other), 1681 mtres, otres); 1682 m.flags_field |= BAD_OVERRIDE; 1683 return; 1684 } 1685 } else if (overrideWarner.hasNonSilentLint(LintCategory.UNCHECKED)) { 1686 warnUnchecked(TreeInfo.diagnosticPositionFor(m, tree), 1687 "override.unchecked.ret", 1688 uncheckedOverrides(m, other), 1689 mtres, otres); 1690 } 1691 1692 // Error if overriding method throws an exception not reported 1693 // by overridden method. 1694 List<Type> otthrown = types.subst(ot.getThrownTypes(), otvars, mtvars); 1695 List<Type> unhandledErased = unhandled(mt.getThrownTypes(), types.erasure(otthrown)); 1696 List<Type> unhandledUnerased = unhandled(mt.getThrownTypes(), otthrown); 1697 if (unhandledErased.nonEmpty()) { 1698 log.error(TreeInfo.diagnosticPositionFor(m, tree), 1699 "override.meth.doesnt.throw", 1700 cannotOverride(m, other), 1701 unhandledUnerased.head); 1702 m.flags_field |= BAD_OVERRIDE; 1703 return; 1704 } 1705 else if (unhandledUnerased.nonEmpty()) { 1706 warnUnchecked(TreeInfo.diagnosticPositionFor(m, tree), 1707 "override.unchecked.thrown", 1708 cannotOverride(m, other), 1709 unhandledUnerased.head); 1710 return; 1711 } 1712 1713 // Optional warning if varargs don't agree 1714 if ((((m.flags() ^ other.flags()) & Flags.VARARGS) != 0) 1715 && lint.isEnabled(LintCategory.OVERRIDES)) { 1716 log.warning(TreeInfo.diagnosticPositionFor(m, tree), 1717 ((m.flags() & Flags.VARARGS) != 0) 1718 ? "override.varargs.missing" 1719 : "override.varargs.extra", 1720 varargsOverrides(m, other)); 1721 } 1722 1723 // Warn if instance method overrides bridge method (compiler spec ??) 1724 if ((other.flags() & BRIDGE) != 0) { 1725 log.warning(TreeInfo.diagnosticPositionFor(m, tree), "override.bridge", 1726 uncheckedOverrides(m, other)); 1727 } 1728 1729 // Warn if a deprecated method overridden by a non-deprecated one. 1730 if (!isDeprecatedOverrideIgnorable(other, origin)) { 1731 checkDeprecated(TreeInfo.diagnosticPositionFor(m, tree), m, other); 1732 } 1733 } 1734 // where 1735 private boolean isDeprecatedOverrideIgnorable(MethodSymbol m, ClassSymbol origin) { 1736 // If the method, m, is defined in an interface, then ignore the issue if the method 1737 // is only inherited via a supertype and also implemented in the supertype, 1738 // because in that case, we will rediscover the issue when examining the method 1739 // in the supertype. 1740 // If the method, m, is not defined in an interface, then the only time we need to 1741 // address the issue is when the method is the supertype implemementation: any other 1742 // case, we will have dealt with when examining the supertype classes 1743 ClassSymbol mc = m.enclClass(); 1744 Type st = types.supertype(origin.type); 1745 if (!st.hasTag(CLASS)) 1746 return true; 1747 MethodSymbol stimpl = m.implementation((ClassSymbol)st.tsym, types, false); 1748 1749 if (mc != null && ((mc.flags() & INTERFACE) != 0)) { 1750 List<Type> intfs = types.interfaces(origin.type); 1751 return (intfs.contains(mc.type) ? false : (stimpl != null)); 1752 } 1753 else 1754 return (stimpl != m); 1755 } 1756 1757 1758 // used to check if there were any unchecked conversions 1759 Warner overrideWarner = new Warner(); 1760 1761 /** Check that a class does not inherit two concrete methods 1762 * with the same signature. 1763 * @param pos Position to be used for error reporting. 1764 * @param site The class type to be checked. 1765 */ 1766 public void checkCompatibleConcretes(DiagnosticPosition pos, Type site) { 1767 Type sup = types.supertype(site); 1768 if (!sup.hasTag(CLASS)) return; 1769 1770 for (Type t1 = sup; 1771 t1.hasTag(CLASS) && t1.tsym.type.isParameterized(); 1772 t1 = types.supertype(t1)) { 1773 for (Scope.Entry e1 = t1.tsym.members().elems; 1774 e1 != null; 1775 e1 = e1.sibling) { 1776 Symbol s1 = e1.sym; 1777 if (s1.kind != MTH || 1778 (s1.flags() & (STATIC|SYNTHETIC|BRIDGE)) != 0 || 1779 !s1.isInheritedIn(site.tsym, types) || 1780 ((MethodSymbol)s1).implementation(site.tsym, 1781 types, 1782 true) != s1) 1783 continue; 1784 Type st1 = types.memberType(t1, s1); 1785 int s1ArgsLength = st1.getParameterTypes().length(); 1786 if (st1 == s1.type) continue; 1787 1788 for (Type t2 = sup; 1789 t2.hasTag(CLASS); 1790 t2 = types.supertype(t2)) { 1791 for (Scope.Entry e2 = t2.tsym.members().lookup(s1.name); 1792 e2.scope != null; 1793 e2 = e2.next()) { 1794 Symbol s2 = e2.sym; 1795 if (s2 == s1 || 1796 s2.kind != MTH || 1797 (s2.flags() & (STATIC|SYNTHETIC|BRIDGE)) != 0 || 1798 s2.type.getParameterTypes().length() != s1ArgsLength || 1799 !s2.isInheritedIn(site.tsym, types) || 1800 ((MethodSymbol)s2).implementation(site.tsym, 1801 types, 1802 true) != s2) 1803 continue; 1804 Type st2 = types.memberType(t2, s2); 1805 if (types.overrideEquivalent(st1, st2)) 1806 log.error(pos, "concrete.inheritance.conflict", 1807 s1, t1, s2, t2, sup); 1808 } 1809 } 1810 } 1811 } 1812 } 1813 1814 /** Check that classes (or interfaces) do not each define an abstract 1815 * method with same name and arguments but incompatible return types. 1816 * @param pos Position to be used for error reporting. 1817 * @param t1 The first argument type. 1818 * @param t2 The second argument type. 1819 */ 1820 public boolean checkCompatibleAbstracts(DiagnosticPosition pos, 1821 Type t1, 1822 Type t2) { 1823 return checkCompatibleAbstracts(pos, t1, t2, 1824 types.makeCompoundType(t1, t2)); 1825 } 1826 1827 public boolean checkCompatibleAbstracts(DiagnosticPosition pos, 1828 Type t1, 1829 Type t2, 1830 Type site) { 1831 return firstIncompatibility(pos, t1, t2, site) == null; 1832 } 1833 1834 /** Return the first method which is defined with same args 1835 * but different return types in two given interfaces, or null if none 1836 * exists. 1837 * @param t1 The first type. 1838 * @param t2 The second type. 1839 * @param site The most derived type. 1840 * @returns symbol from t2 that conflicts with one in t1. 1841 */ 1842 private Symbol firstIncompatibility(DiagnosticPosition pos, Type t1, Type t2, Type site) { 1843 Map<TypeSymbol,Type> interfaces1 = new HashMap<TypeSymbol,Type>(); 1844 closure(t1, interfaces1); 1845 Map<TypeSymbol,Type> interfaces2; 1846 if (t1 == t2) 1847 interfaces2 = interfaces1; 1848 else 1849 closure(t2, interfaces1, interfaces2 = new HashMap<TypeSymbol,Type>()); 1850 1851 for (Type t3 : interfaces1.values()) { 1852 for (Type t4 : interfaces2.values()) { 1853 Symbol s = firstDirectIncompatibility(pos, t3, t4, site); 1854 if (s != null) return s; 1855 } 1856 } 1857 return null; 1858 } 1859 1860 /** Compute all the supertypes of t, indexed by type symbol. */ 1861 private void closure(Type t, Map<TypeSymbol,Type> typeMap) { 1862 if (!t.hasTag(CLASS)) return; 1863 if (typeMap.put(t.tsym, t) == null) { 1864 closure(types.supertype(t), typeMap); 1865 for (Type i : types.interfaces(t)) 1866 closure(i, typeMap); 1867 } 1868 } 1869 1870 /** Compute all the supertypes of t, indexed by type symbol (except thise in typesSkip). */ 1871 private void closure(Type t, Map<TypeSymbol,Type> typesSkip, Map<TypeSymbol,Type> typeMap) { 1872 if (!t.hasTag(CLASS)) return; 1873 if (typesSkip.get(t.tsym) != null) return; 1874 if (typeMap.put(t.tsym, t) == null) { 1875 closure(types.supertype(t), typesSkip, typeMap); 1876 for (Type i : types.interfaces(t)) 1877 closure(i, typesSkip, typeMap); 1878 } 1879 } 1880 1881 /** Return the first method in t2 that conflicts with a method from t1. */ 1882 private Symbol firstDirectIncompatibility(DiagnosticPosition pos, Type t1, Type t2, Type site) { 1883 for (Scope.Entry e1 = t1.tsym.members().elems; e1 != null; e1 = e1.sibling) { 1884 Symbol s1 = e1.sym; 1885 Type st1 = null; 1886 if (s1.kind != MTH || !s1.isInheritedIn(site.tsym, types) || 1887 (s1.flags() & SYNTHETIC) != 0) continue; 1888 Symbol impl = ((MethodSymbol)s1).implementation(site.tsym, types, false); 1889 if (impl != null && (impl.flags() & ABSTRACT) == 0) continue; 1890 for (Scope.Entry e2 = t2.tsym.members().lookup(s1.name); e2.scope != null; e2 = e2.next()) { 1891 Symbol s2 = e2.sym; 1892 if (s1 == s2) continue; 1893 if (s2.kind != MTH || !s2.isInheritedIn(site.tsym, types) || 1894 (s2.flags() & SYNTHETIC) != 0) continue; 1895 if (st1 == null) st1 = types.memberType(t1, s1); 1896 Type st2 = types.memberType(t2, s2); 1897 if (types.overrideEquivalent(st1, st2)) { 1898 List<Type> tvars1 = st1.getTypeArguments(); 1899 List<Type> tvars2 = st2.getTypeArguments(); 1900 Type rt1 = st1.getReturnType(); 1901 Type rt2 = types.subst(st2.getReturnType(), tvars2, tvars1); 1902 boolean compat = 1903 types.isSameType(rt1, rt2) || 1904 !rt1.isPrimitiveOrVoid() && 1905 !rt2.isPrimitiveOrVoid() && 1906 (types.covariantReturnType(rt1, rt2, types.noWarnings) || 1907 types.covariantReturnType(rt2, rt1, types.noWarnings)) || 1908 checkCommonOverriderIn(s1,s2,site); 1909 if (!compat) { 1910 log.error(pos, "types.incompatible.diff.ret", 1911 t1, t2, s2.name + 1912 "(" + types.memberType(t2, s2).getParameterTypes() + ")"); 1913 return s2; 1914 } 1915 } else if (checkNameClash((ClassSymbol)site.tsym, s1, s2) && 1916 !checkCommonOverriderIn(s1, s2, site)) { 1917 log.error(pos, 1918 "name.clash.same.erasure.no.override", 1919 s1, s1.location(), 1920 s2, s2.location()); 1921 return s2; 1922 } 1923 } 1924 } 1925 return null; 1926 } 1927 //WHERE 1928 boolean checkCommonOverriderIn(Symbol s1, Symbol s2, Type site) { 1929 Map<TypeSymbol,Type> supertypes = new HashMap<TypeSymbol,Type>(); 1930 Type st1 = types.memberType(site, s1); 1931 Type st2 = types.memberType(site, s2); 1932 closure(site, supertypes); 1933 for (Type t : supertypes.values()) { 1934 for (Scope.Entry e = t.tsym.members().lookup(s1.name); e.scope != null; e = e.next()) { 1935 Symbol s3 = e.sym; 1936 if (s3 == s1 || s3 == s2 || s3.kind != MTH || (s3.flags() & (BRIDGE|SYNTHETIC)) != 0) continue; 1937 Type st3 = types.memberType(site,s3); 1938 if (types.overrideEquivalent(st3, st1) && 1939 types.overrideEquivalent(st3, st2) && 1940 types.returnTypeSubstitutable(st3, st1) && 1941 types.returnTypeSubstitutable(st3, st2)) { 1942 return true; 1943 } 1944 } 1945 } 1946 return false; 1947 } 1948 1949 /** Check that a given method conforms with any method it overrides. 1950 * @param tree The tree from which positions are extracted 1951 * for errors. 1952 * @param m The overriding method. 1953 */ 1954 void checkOverride(JCTree tree, MethodSymbol m) { 1955 ClassSymbol origin = (ClassSymbol)m.owner; 1956 if ((origin.flags() & ENUM) != 0 && names.finalize.equals(m.name)) 1957 if (m.overrides(syms.enumFinalFinalize, origin, types, false)) { 1958 log.error(tree.pos(), "enum.no.finalize"); 1959 return; 1960 } 1961 for (Type t = origin.type; t.hasTag(CLASS); 1962 t = types.supertype(t)) { 1963 if (t != origin.type) { 1964 checkOverride(tree, t, origin, m); 1965 } 1966 for (Type t2 : types.interfaces(t)) { 1967 checkOverride(tree, t2, origin, m); 1968 } 1969 } 1970 } 1971 1972 void checkOverride(JCTree tree, Type site, ClassSymbol origin, MethodSymbol m) { 1973 TypeSymbol c = site.tsym; 1974 Scope.Entry e = c.members().lookup(m.name); 1975 while (e.scope != null) { 1976 if (m.overrides(e.sym, origin, types, false)) { 1977 if ((e.sym.flags() & ABSTRACT) == 0) { 1978 checkOverride(tree, m, (MethodSymbol)e.sym, origin); 1979 } 1980 } 1981 e = e.next(); 1982 } 1983 } 1984 1985 private Filter<Symbol> equalsHasCodeFilter = new Filter<Symbol>() { 1986 public boolean accepts(Symbol s) { 1987 return MethodSymbol.implementation_filter.accepts(s) && 1988 (s.flags() & BAD_OVERRIDE) == 0; 1989 1990 } 1991 }; 1992 1993 public void checkClassOverrideEqualsAndHashIfNeeded(DiagnosticPosition pos, 1994 ClassSymbol someClass) { 1995 /* At present, annotations cannot possibly have a method that is override 1996 * equivalent with Object.equals(Object) but in any case the condition is 1997 * fine for completeness. 1998 */ 1999 if (someClass == (ClassSymbol)syms.objectType.tsym || 2000 someClass.isInterface() || someClass.isEnum() || 2001 (someClass.flags() & ANNOTATION) != 0 || 2002 (someClass.flags() & ABSTRACT) != 0) return; 2003 //anonymous inner classes implementing interfaces need especial treatment 2004 if (someClass.isAnonymous()) { 2005 List<Type> interfaces = types.interfaces(someClass.type); 2006 if (interfaces != null && !interfaces.isEmpty() && 2007 interfaces.head.tsym == syms.comparatorType.tsym) return; 2008 } 2009 checkClassOverrideEqualsAndHash(pos, someClass); 2010 } 2011 2012 private void checkClassOverrideEqualsAndHash(DiagnosticPosition pos, 2013 ClassSymbol someClass) { 2014 if (lint.isEnabled(LintCategory.OVERRIDES)) { 2015 MethodSymbol equalsAtObject = (MethodSymbol)syms.objectType 2016 .tsym.members().lookup(names.equals).sym; 2017 MethodSymbol hashCodeAtObject = (MethodSymbol)syms.objectType 2018 .tsym.members().lookup(names.hashCode).sym; 2019 boolean overridesEquals = types.implementation(equalsAtObject, 2020 someClass, false, equalsHasCodeFilter).owner == someClass; 2021 boolean overridesHashCode = types.implementation(hashCodeAtObject, 2022 someClass, false, equalsHasCodeFilter) != hashCodeAtObject; 2023 2024 if (overridesEquals && !overridesHashCode) { 2025 log.warning(LintCategory.OVERRIDES, pos, 2026 "override.equals.but.not.hashcode", someClass); 2027 } 2028 } 2029 } 2030 2031 private boolean checkNameClash(ClassSymbol origin, Symbol s1, Symbol s2) { 2032 ClashFilter cf = new ClashFilter(origin.type); 2033 return (cf.accepts(s1) && 2034 cf.accepts(s2) && 2035 types.hasSameArgs(s1.erasure(types), s2.erasure(types))); 2036 } 2037 2038 2039 /** Check that all abstract members of given class have definitions. 2040 * @param pos Position to be used for error reporting. 2041 * @param c The class. 2042 */ 2043 void checkAllDefined(DiagnosticPosition pos, ClassSymbol c) { 2044 try { 2045 MethodSymbol undef = firstUndef(c, c); 2046 if (undef != null) { 2047 if ((c.flags() & ENUM) != 0 && 2048 types.supertype(c.type).tsym == syms.enumSym && 2049 (c.flags() & FINAL) == 0) { 2050 // add the ABSTRACT flag to an enum 2051 c.flags_field |= ABSTRACT; 2052 } else { 2053 MethodSymbol undef1 = 2054 new MethodSymbol(undef.flags(), undef.name, 2055 types.memberType(c.type, undef), undef.owner); 2056 log.error(pos, "does.not.override.abstract", 2057 c, undef1, undef1.location()); 2058 } 2059 } 2060 } catch (CompletionFailure ex) { 2061 completionError(pos, ex); 2062 } 2063 } 2064 //where 2065 /** Return first abstract member of class `c' that is not defined 2066 * in `impl', null if there is none. 2067 */ 2068 private MethodSymbol firstUndef(ClassSymbol impl, ClassSymbol c) { 2069 MethodSymbol undef = null; 2070 // Do not bother to search in classes that are not abstract, 2071 // since they cannot have abstract members. 2072 if (c == impl || (c.flags() & (ABSTRACT | INTERFACE)) != 0) { 2073 Scope s = c.members(); 2074 for (Scope.Entry e = s.elems; 2075 undef == null && e != null; 2076 e = e.sibling) { 2077 if (e.sym.kind == MTH && 2078 (e.sym.flags() & (ABSTRACT|IPROXY|DEFAULT)) == ABSTRACT) { 2079 MethodSymbol absmeth = (MethodSymbol)e.sym; 2080 MethodSymbol implmeth = absmeth.implementation(impl, types, true); 2081 if (implmeth == null || implmeth == absmeth) { 2082 //look for default implementations 2083 if (allowDefaultMethods) { 2084 MethodSymbol prov = types.interfaceCandidates(impl.type, absmeth).head; 2085 if (prov != null && prov.overrides(absmeth, impl, types, true)) { 2086 implmeth = prov; 2087 } 2088 } 2089 } 2090 if (implmeth == null || implmeth == absmeth) { 2091 undef = absmeth; 2092 } 2093 } 2094 } 2095 if (undef == null) { 2096 Type st = types.supertype(c.type); 2097 if (st.hasTag(CLASS)) 2098 undef = firstUndef(impl, (ClassSymbol)st.tsym); 2099 } 2100 for (List<Type> l = types.interfaces(c.type); 2101 undef == null && l.nonEmpty(); 2102 l = l.tail) { 2103 undef = firstUndef(impl, (ClassSymbol)l.head.tsym); 2104 } 2105 } 2106 return undef; 2107 } 2108 2109 void checkNonCyclicDecl(JCClassDecl tree) { 2110 CycleChecker cc = new CycleChecker(); 2111 cc.scan(tree); 2112 if (!cc.errorFound && !cc.partialCheck) { 2113 tree.sym.flags_field |= ACYCLIC; 2114 } 2115 } 2116 2117 class CycleChecker extends TreeScanner { 2118 2119 List<Symbol> seenClasses = List.nil(); 2120 boolean errorFound = false; 2121 boolean partialCheck = false; 2122 2123 private void checkSymbol(DiagnosticPosition pos, Symbol sym) { 2124 if (sym != null && sym.kind == TYP) { 2125 Env<AttrContext> classEnv = enter.getEnv((TypeSymbol)sym); 2126 if (classEnv != null) { 2127 DiagnosticSource prevSource = log.currentSource(); 2128 try { 2129 log.useSource(classEnv.toplevel.sourcefile); 2130 scan(classEnv.tree); 2131 } 2132 finally { 2133 log.useSource(prevSource.getFile()); 2134 } 2135 } else if (sym.kind == TYP) { 2136 checkClass(pos, sym, List.<JCTree>nil()); 2137 } 2138 } else { 2139 //not completed yet 2140 partialCheck = true; 2141 } 2142 } 2143 2144 @Override 2145 public void visitSelect(JCFieldAccess tree) { 2146 super.visitSelect(tree); 2147 checkSymbol(tree.pos(), tree.sym); 2148 } 2149 2150 @Override 2151 public void visitIdent(JCIdent tree) { 2152 checkSymbol(tree.pos(), tree.sym); 2153 } 2154 2155 @Override 2156 public void visitTypeApply(JCTypeApply tree) { 2157 scan(tree.clazz); 2158 } 2159 2160 @Override 2161 public void visitTypeArray(JCArrayTypeTree tree) { 2162 scan(tree.elemtype); 2163 } 2164 2165 @Override 2166 public void visitClassDef(JCClassDecl tree) { 2167 List<JCTree> supertypes = List.nil(); 2168 if (tree.getExtendsClause() != null) { 2169 supertypes = supertypes.prepend(tree.getExtendsClause()); 2170 } 2171 if (tree.getImplementsClause() != null) { 2172 for (JCTree intf : tree.getImplementsClause()) { 2173 supertypes = supertypes.prepend(intf); 2174 } 2175 } 2176 checkClass(tree.pos(), tree.sym, supertypes); 2177 } 2178 2179 void checkClass(DiagnosticPosition pos, Symbol c, List<JCTree> supertypes) { 2180 if ((c.flags_field & ACYCLIC) != 0) 2181 return; 2182 if (seenClasses.contains(c)) { 2183 errorFound = true; 2184 noteCyclic(pos, (ClassSymbol)c); 2185 } else if (!c.type.isErroneous()) { 2186 try { 2187 seenClasses = seenClasses.prepend(c); 2188 if (c.type.hasTag(CLASS)) { 2189 if (supertypes.nonEmpty()) { 2190 scan(supertypes); 2191 } 2192 else { 2193 ClassType ct = (ClassType)c.type; 2194 if (ct.supertype_field == null || 2195 ct.interfaces_field == null) { 2196 //not completed yet 2197 partialCheck = true; 2198 return; 2199 } 2200 checkSymbol(pos, ct.supertype_field.tsym); 2201 for (Type intf : ct.interfaces_field) { 2202 checkSymbol(pos, intf.tsym); 2203 } 2204 } 2205 if (c.owner.kind == TYP) { 2206 checkSymbol(pos, c.owner); 2207 } 2208 } 2209 } finally { 2210 seenClasses = seenClasses.tail; 2211 } 2212 } 2213 } 2214 } 2215 2216 /** Check for cyclic references. Issue an error if the 2217 * symbol of the type referred to has a LOCKED flag set. 2218 * 2219 * @param pos Position to be used for error reporting. 2220 * @param t The type referred to. 2221 */ 2222 void checkNonCyclic(DiagnosticPosition pos, Type t) { 2223 checkNonCyclicInternal(pos, t); 2224 } 2225 2226 2227 void checkNonCyclic(DiagnosticPosition pos, TypeVar t) { 2228 checkNonCyclic1(pos, t, List.<TypeVar>nil()); 2229 } 2230 2231 private void checkNonCyclic1(DiagnosticPosition pos, Type t, List<TypeVar> seen) { 2232 final TypeVar tv; 2233 if (t.hasTag(TYPEVAR) && (t.tsym.flags() & UNATTRIBUTED) != 0) 2234 return; 2235 if (seen.contains(t)) { 2236 tv = (TypeVar)t.unannotatedType(); 2237 tv.bound = types.createErrorType(t); 2238 log.error(pos, "cyclic.inheritance", t); 2239 } else if (t.hasTag(TYPEVAR)) { 2240 tv = (TypeVar)t.unannotatedType(); 2241 seen = seen.prepend(tv); 2242 for (Type b : types.getBounds(tv)) 2243 checkNonCyclic1(pos, b, seen); 2244 } else if (t.hasTag(ARRAY)) { 2245 final ArrayType at = (ArrayType)t.unannotatedType(); 2246 checkNonCyclic1(pos, at.elemtype, seen); 2247 } 2248 } 2249 2250 /** Check for cyclic references. Issue an error if the 2251 * symbol of the type referred to has a LOCKED flag set. 2252 * 2253 * @param pos Position to be used for error reporting. 2254 * @param t The type referred to. 2255 * @returns True if the check completed on all attributed classes 2256 */ 2257 private boolean checkNonCyclicInternal(DiagnosticPosition pos, Type t) { 2258 boolean complete = true; // was the check complete? 2259 //- System.err.println("checkNonCyclicInternal("+t+");");//DEBUG 2260 Symbol c = t.tsym; 2261 if ((c.flags_field & ACYCLIC) != 0) return true; 2262 2263 if ((c.flags_field & LOCKED) != 0) { 2264 noteCyclic(pos, (ClassSymbol)c); 2265 } else if (!c.type.isErroneous()) { 2266 try { 2267 c.flags_field |= LOCKED; 2268 if (c.type.hasTag(CLASS)) { 2269 ClassType clazz = (ClassType)c.type; 2270 if (clazz.interfaces_field != null) 2271 for (List<Type> l=clazz.interfaces_field; l.nonEmpty(); l=l.tail) 2272 complete &= checkNonCyclicInternal(pos, l.head); 2273 if (clazz.supertype_field != null) { 2274 Type st = clazz.supertype_field; 2275 if (st != null && st.hasTag(CLASS)) 2276 complete &= checkNonCyclicInternal(pos, st); 2277 } 2278 if (c.owner.kind == TYP) 2279 complete &= checkNonCyclicInternal(pos, c.owner.type); 2280 } 2281 } finally { 2282 c.flags_field &= ~LOCKED; 2283 } 2284 } 2285 if (complete) 2286 complete = ((c.flags_field & UNATTRIBUTED) == 0) && c.completer == null; 2287 if (complete) c.flags_field |= ACYCLIC; 2288 return complete; 2289 } 2290 2291 /** Note that we found an inheritance cycle. */ 2292 private void noteCyclic(DiagnosticPosition pos, ClassSymbol c) { 2293 log.error(pos, "cyclic.inheritance", c); 2294 for (List<Type> l=types.interfaces(c.type); l.nonEmpty(); l=l.tail) 2295 l.head = types.createErrorType((ClassSymbol)l.head.tsym, Type.noType); 2296 Type st = types.supertype(c.type); 2297 if (st.hasTag(CLASS)) 2298 ((ClassType)c.type).supertype_field = types.createErrorType((ClassSymbol)st.tsym, Type.noType); 2299 c.type = types.createErrorType(c, c.type); 2300 c.flags_field |= ACYCLIC; 2301 } 2302 2303 /** Check that all methods which implement some 2304 * method conform to the method they implement. 2305 * @param tree The class definition whose members are checked. 2306 */ 2307 void checkImplementations(JCClassDecl tree) { 2308 checkImplementations(tree, tree.sym, tree.sym); 2309 } 2310 //where 2311 /** Check that all methods which implement some 2312 * method in `ic' conform to the method they implement. 2313 */ 2314 void checkImplementations(JCTree tree, ClassSymbol origin, ClassSymbol ic) { 2315 for (List<Type> l = types.closure(ic.type); l.nonEmpty(); l = l.tail) { 2316 ClassSymbol lc = (ClassSymbol)l.head.tsym; 2317 if ((allowGenerics || origin != lc) && (lc.flags() & ABSTRACT) != 0) { 2318 for (Scope.Entry e=lc.members().elems; e != null; e=e.sibling) { 2319 if (e.sym.kind == MTH && 2320 (e.sym.flags() & (STATIC|ABSTRACT)) == ABSTRACT) { 2321 MethodSymbol absmeth = (MethodSymbol)e.sym; 2322 MethodSymbol implmeth = absmeth.implementation(origin, types, false); 2323 if (implmeth != null && implmeth != absmeth && 2324 (implmeth.owner.flags() & INTERFACE) == 2325 (origin.flags() & INTERFACE)) { 2326 // don't check if implmeth is in a class, yet 2327 // origin is an interface. This case arises only 2328 // if implmeth is declared in Object. The reason is 2329 // that interfaces really don't inherit from 2330 // Object it's just that the compiler represents 2331 // things that way. 2332 checkOverride(tree, implmeth, absmeth, origin); 2333 } 2334 } 2335 } 2336 } 2337 } 2338 } 2339 2340 /** Check that all abstract methods implemented by a class are 2341 * mutually compatible. 2342 * @param pos Position to be used for error reporting. 2343 * @param c The class whose interfaces are checked. 2344 */ 2345 void checkCompatibleSupertypes(DiagnosticPosition pos, Type c) { 2346 List<Type> supertypes = types.interfaces(c); 2347 Type supertype = types.supertype(c); 2348 if (supertype.hasTag(CLASS) && 2349 (supertype.tsym.flags() & ABSTRACT) != 0) 2350 supertypes = supertypes.prepend(supertype); 2351 for (List<Type> l = supertypes; l.nonEmpty(); l = l.tail) { 2352 if (allowGenerics && !l.head.getTypeArguments().isEmpty() && 2353 !checkCompatibleAbstracts(pos, l.head, l.head, c)) 2354 return; 2355 for (List<Type> m = supertypes; m != l; m = m.tail) 2356 if (!checkCompatibleAbstracts(pos, l.head, m.head, c)) 2357 return; 2358 } 2359 checkCompatibleConcretes(pos, c); 2360 } 2361 2362 void checkConflicts(DiagnosticPosition pos, Symbol sym, TypeSymbol c) { 2363 for (Type ct = c.type; ct != Type.noType ; ct = types.supertype(ct)) { 2364 for (Scope.Entry e = ct.tsym.members().lookup(sym.name); e.scope == ct.tsym.members(); e = e.next()) { 2365 // VM allows methods and variables with differing types 2366 if (sym.kind == e.sym.kind && 2367 types.isSameType(types.erasure(sym.type), types.erasure(e.sym.type)) && 2368 sym != e.sym && 2369 (sym.flags() & Flags.SYNTHETIC) != (e.sym.flags() & Flags.SYNTHETIC) && 2370 (sym.flags() & IPROXY) == 0 && (e.sym.flags() & IPROXY) == 0 && 2371 (sym.flags() & BRIDGE) == 0 && (e.sym.flags() & BRIDGE) == 0) { 2372 syntheticError(pos, (e.sym.flags() & SYNTHETIC) == 0 ? e.sym : sym); 2373 return; 2374 } 2375 } 2376 } 2377 } 2378 2379 /** Check that all non-override equivalent methods accessible from 'site' 2380 * are mutually compatible (JLS 8.4.8/9.4.1). 2381 * 2382 * @param pos Position to be used for error reporting. 2383 * @param site The class whose methods are checked. 2384 * @param sym The method symbol to be checked. 2385 */ 2386 void checkOverrideClashes(DiagnosticPosition pos, Type site, MethodSymbol sym) { 2387 ClashFilter cf = new ClashFilter(site); 2388 //for each method m1 that is overridden (directly or indirectly) 2389 //by method 'sym' in 'site'... 2390 for (Symbol m1 : types.membersClosure(site, false).getElementsByName(sym.name, cf)) { 2391 if (!sym.overrides(m1, site.tsym, types, false)) { 2392 checkPotentiallyAmbiguousOverloads(pos, site, sym, (MethodSymbol)m1); 2393 continue; 2394 } 2395 //...check each method m2 that is a member of 'site' 2396 for (Symbol m2 : types.membersClosure(site, false).getElementsByName(sym.name, cf)) { 2397 if (m2 == m1) continue; 2398 //if (i) the signature of 'sym' is not a subsignature of m1 (seen as 2399 //a member of 'site') and (ii) m1 has the same erasure as m2, issue an error 2400 if (!types.isSubSignature(sym.type, types.memberType(site, m2), allowStrictMethodClashCheck) && 2401 types.hasSameArgs(m2.erasure(types), m1.erasure(types))) { 2402 sym.flags_field |= CLASH; 2403 String key = m1 == sym ? 2404 "name.clash.same.erasure.no.override" : 2405 "name.clash.same.erasure.no.override.1"; 2406 log.error(pos, 2407 key, 2408 sym, sym.location(), 2409 m2, m2.location(), 2410 m1, m1.location()); 2411 return; 2412 } 2413 } 2414 } 2415 } 2416 2417 2418 2419 /** Check that all static methods accessible from 'site' are 2420 * mutually compatible (JLS 8.4.8). 2421 * 2422 * @param pos Position to be used for error reporting. 2423 * @param site The class whose methods are checked. 2424 * @param sym The method symbol to be checked. 2425 */ 2426 void checkHideClashes(DiagnosticPosition pos, Type site, MethodSymbol sym) { 2427 ClashFilter cf = new ClashFilter(site); 2428 //for each method m1 that is a member of 'site'... 2429 for (Symbol s : types.membersClosure(site, true).getElementsByName(sym.name, cf)) { 2430 //if (i) the signature of 'sym' is not a subsignature of m1 (seen as 2431 //a member of 'site') and (ii) 'sym' has the same erasure as m1, issue an error 2432 if (!types.isSubSignature(sym.type, types.memberType(site, s), allowStrictMethodClashCheck)) { 2433 if (types.hasSameArgs(s.erasure(types), sym.erasure(types))) { 2434 log.error(pos, 2435 "name.clash.same.erasure.no.hide", 2436 sym, sym.location(), 2437 s, s.location()); 2438 return; 2439 } else { 2440 checkPotentiallyAmbiguousOverloads(pos, site, sym, (MethodSymbol)s); 2441 } 2442 } 2443 } 2444 } 2445 2446 //where 2447 private class ClashFilter implements Filter<Symbol> { 2448 2449 Type site; 2450 2451 ClashFilter(Type site) { 2452 this.site = site; 2453 } 2454 2455 boolean shouldSkip(Symbol s) { 2456 return (s.flags() & CLASH) != 0 && 2457 s.owner == site.tsym; 2458 } 2459 2460 public boolean accepts(Symbol s) { 2461 return s.kind == MTH && 2462 (s.flags() & SYNTHETIC) == 0 && 2463 !shouldSkip(s) && 2464 s.isInheritedIn(site.tsym, types) && 2465 !s.isConstructor(); 2466 } 2467 } 2468 2469 void checkDefaultMethodClashes(DiagnosticPosition pos, Type site) { 2470 DefaultMethodClashFilter dcf = new DefaultMethodClashFilter(site); 2471 for (Symbol m : types.membersClosure(site, false).getElements(dcf)) { 2472 Assert.check(m.kind == MTH); 2473 List<MethodSymbol> prov = types.interfaceCandidates(site, (MethodSymbol)m); 2474 if (prov.size() > 1) { 2475 ListBuffer<Symbol> abstracts = new ListBuffer<>(); 2476 ListBuffer<Symbol> defaults = new ListBuffer<>(); 2477 for (MethodSymbol provSym : prov) { 2478 if ((provSym.flags() & DEFAULT) != 0) { 2479 defaults = defaults.append(provSym); 2480 } else if ((provSym.flags() & ABSTRACT) != 0) { 2481 abstracts = abstracts.append(provSym); 2482 } 2483 if (defaults.nonEmpty() && defaults.size() + abstracts.size() >= 2) { 2484 //strong semantics - issue an error if two sibling interfaces 2485 //have two override-equivalent defaults - or if one is abstract 2486 //and the other is default 2487 String errKey; 2488 Symbol s1 = defaults.first(); 2489 Symbol s2; 2490 if (defaults.size() > 1) { 2491 errKey = "types.incompatible.unrelated.defaults"; 2492 s2 = defaults.toList().tail.head; 2493 } else { 2494 errKey = "types.incompatible.abstract.default"; 2495 s2 = abstracts.first(); 2496 } 2497 log.error(pos, errKey, 2498 Kinds.kindName(site.tsym), site, 2499 m.name, types.memberType(site, m).getParameterTypes(), 2500 s1.location(), s2.location()); 2501 break; 2502 } 2503 } 2504 } 2505 } 2506 } 2507 2508 //where 2509 private class DefaultMethodClashFilter implements Filter<Symbol> { 2510 2511 Type site; 2512 2513 DefaultMethodClashFilter(Type site) { 2514 this.site = site; 2515 } 2516 2517 public boolean accepts(Symbol s) { 2518 return s.kind == MTH && 2519 (s.flags() & DEFAULT) != 0 && 2520 s.isInheritedIn(site.tsym, types) && 2521 !s.isConstructor(); 2522 } 2523 } 2524 2525 /** 2526 * Report warnings for potentially ambiguous method declarations. Two declarations 2527 * are potentially ambiguous if they feature two unrelated functional interface 2528 * in same argument position (in which case, a call site passing an implicit 2529 * lambda would be ambiguous). 2530 */ 2531 void checkPotentiallyAmbiguousOverloads(DiagnosticPosition pos, Type site, 2532 MethodSymbol msym1, MethodSymbol msym2) { 2533 if (msym1 != msym2 && 2534 allowDefaultMethods && 2535 lint.isEnabled(LintCategory.OVERLOADS) && 2536 (msym1.flags() & POTENTIALLY_AMBIGUOUS) == 0 && 2537 (msym2.flags() & POTENTIALLY_AMBIGUOUS) == 0) { 2538 Type mt1 = types.memberType(site, msym1); 2539 Type mt2 = types.memberType(site, msym2); 2540 //if both generic methods, adjust type variables 2541 if (mt1.hasTag(FORALL) && mt2.hasTag(FORALL) && 2542 types.hasSameBounds((ForAll)mt1, (ForAll)mt2)) { 2543 mt2 = types.subst(mt2, ((ForAll)mt2).tvars, ((ForAll)mt1).tvars); 2544 } 2545 //expand varargs methods if needed 2546 int maxLength = Math.max(mt1.getParameterTypes().length(), mt2.getParameterTypes().length()); 2547 List<Type> args1 = rs.adjustArgs(mt1.getParameterTypes(), msym1, maxLength, true); 2548 List<Type> args2 = rs.adjustArgs(mt2.getParameterTypes(), msym2, maxLength, true); 2549 //if arities don't match, exit 2550 if (args1.length() != args2.length()) return; 2551 boolean potentiallyAmbiguous = false; 2552 while (args1.nonEmpty() && args2.nonEmpty()) { 2553 Type s = args1.head; 2554 Type t = args2.head; 2555 if (!types.isSubtype(t, s) && !types.isSubtype(s, t)) { 2556 if (types.isFunctionalInterface(s) && types.isFunctionalInterface(t) && 2557 types.findDescriptorType(s).getParameterTypes().length() > 0 && 2558 types.findDescriptorType(s).getParameterTypes().length() == 2559 types.findDescriptorType(t).getParameterTypes().length()) { 2560 potentiallyAmbiguous = true; 2561 } else { 2562 break; 2563 } 2564 } 2565 args1 = args1.tail; 2566 args2 = args2.tail; 2567 } 2568 if (potentiallyAmbiguous) { 2569 //we found two incompatible functional interfaces with same arity 2570 //this means a call site passing an implicit lambda would be ambigiuous 2571 msym1.flags_field |= POTENTIALLY_AMBIGUOUS; 2572 msym2.flags_field |= POTENTIALLY_AMBIGUOUS; 2573 log.warning(LintCategory.OVERLOADS, pos, "potentially.ambiguous.overload", 2574 msym1, msym1.location(), 2575 msym2, msym2.location()); 2576 return; 2577 } 2578 } 2579 } 2580 2581 /** Report a conflict between a user symbol and a synthetic symbol. 2582 */ 2583 private void syntheticError(DiagnosticPosition pos, Symbol sym) { 2584 if (!sym.type.isErroneous()) { 2585 if (warnOnSyntheticConflicts) { 2586 log.warning(pos, "synthetic.name.conflict", sym, sym.location()); 2587 } 2588 else { 2589 log.error(pos, "synthetic.name.conflict", sym, sym.location()); 2590 } 2591 } 2592 } 2593 2594 /** Check that class c does not implement directly or indirectly 2595 * the same parameterized interface with two different argument lists. 2596 * @param pos Position to be used for error reporting. 2597 * @param type The type whose interfaces are checked. 2598 */ 2599 void checkClassBounds(DiagnosticPosition pos, Type type) { 2600 checkClassBounds(pos, new HashMap<TypeSymbol,Type>(), type); 2601 } 2602 //where 2603 /** Enter all interfaces of type `type' into the hash table `seensofar' 2604 * with their class symbol as key and their type as value. Make 2605 * sure no class is entered with two different types. 2606 */ 2607 void checkClassBounds(DiagnosticPosition pos, 2608 Map<TypeSymbol,Type> seensofar, 2609 Type type) { 2610 if (type.isErroneous()) return; 2611 for (List<Type> l = types.interfaces(type); l.nonEmpty(); l = l.tail) { 2612 Type it = l.head; 2613 Type oldit = seensofar.put(it.tsym, it); 2614 if (oldit != null) { 2615 List<Type> oldparams = oldit.allparams(); 2616 List<Type> newparams = it.allparams(); 2617 if (!types.containsTypeEquivalent(oldparams, newparams)) 2618 log.error(pos, "cant.inherit.diff.arg", 2619 it.tsym, Type.toString(oldparams), 2620 Type.toString(newparams)); 2621 } 2622 checkClassBounds(pos, seensofar, it); 2623 } 2624 Type st = types.supertype(type); 2625 if (st != null) checkClassBounds(pos, seensofar, st); 2626 } 2627 2628 /** Enter interface into into set. 2629 * If it existed already, issue a "repeated interface" error. 2630 */ 2631 void checkNotRepeated(DiagnosticPosition pos, Type it, Set<Type> its) { 2632 if (its.contains(it)) 2633 log.error(pos, "repeated.interface"); 2634 else { 2635 its.add(it); 2636 } 2637 } 2638 2639 /* ************************************************************************* 2640 * Check annotations 2641 **************************************************************************/ 2642 2643 /** 2644 * Recursively validate annotations values 2645 */ 2646 void validateAnnotationTree(JCTree tree) { 2647 class AnnotationValidator extends TreeScanner { 2648 @Override 2649 public void visitAnnotation(JCAnnotation tree) { 2650 if (!tree.type.isErroneous()) { 2651 super.visitAnnotation(tree); 2652 validateAnnotation(tree); 2653 } 2654 } 2655 } 2656 tree.accept(new AnnotationValidator()); 2657 } 2658 2659 /** 2660 * {@literal 2661 * Annotation types are restricted to primitives, String, an 2662 * enum, an annotation, Class, Class<?>, Class<? extends 2663 * Anything>, arrays of the preceding. 2664 * } 2665 */ 2666 void validateAnnotationType(JCTree restype) { 2667 // restype may be null if an error occurred, so don't bother validating it 2668 if (restype != null) { 2669 validateAnnotationType(restype.pos(), restype.type); 2670 } 2671 } 2672 2673 void validateAnnotationType(DiagnosticPosition pos, Type type) { 2674 if (type.isPrimitive()) return; 2675 if (types.isSameType(type, syms.stringType)) return; 2676 if ((type.tsym.flags() & Flags.ENUM) != 0) return; 2677 if ((type.tsym.flags() & Flags.ANNOTATION) != 0) return; 2678 if (types.lowerBound(type).tsym == syms.classType.tsym) return; 2679 if (types.isArray(type) && !types.isArray(types.elemtype(type))) { 2680 validateAnnotationType(pos, types.elemtype(type)); 2681 return; 2682 } 2683 log.error(pos, "annotation.invalid.element.type"); 2684 } 2685 2686 /** 2687 * "It is also a compile-time error if any method declared in an 2688 * annotation type has a signature that is override-equivalent to 2689 * that of any public or protected method declared in class Object 2690 * or in the interface annotation.Annotation." 2691 * 2692 * @jls 9.6 Annotation Types 2693 */ 2694 void validateAnnotationMethod(DiagnosticPosition pos, MethodSymbol m) { 2695 for (Type sup = syms.annotationType; sup.hasTag(CLASS); sup = types.supertype(sup)) { 2696 Scope s = sup.tsym.members(); 2697 for (Scope.Entry e = s.lookup(m.name); e.scope != null; e = e.next()) { 2698 if (e.sym.kind == MTH && 2699 (e.sym.flags() & (PUBLIC | PROTECTED)) != 0 && 2700 types.overrideEquivalent(m.type, e.sym.type)) 2701 log.error(pos, "intf.annotation.member.clash", e.sym, sup); 2702 } 2703 } 2704 } 2705 2706 /** Check the annotations of a symbol. 2707 */ 2708 public void validateAnnotations(List<JCAnnotation> annotations, Symbol s) { 2709 for (JCAnnotation a : annotations) 2710 validateAnnotation(a, s); 2711 } 2712 2713 /** Check the type annotations. 2714 */ 2715 public void validateTypeAnnotations(List<JCAnnotation> annotations, boolean isTypeParameter) { 2716 for (JCAnnotation a : annotations) 2717 validateTypeAnnotation(a, isTypeParameter); 2718 } 2719 2720 /** Check an annotation of a symbol. 2721 */ 2722 private void validateAnnotation(JCAnnotation a, Symbol s) { 2723 validateAnnotationTree(a); 2724 2725 if (!annotationApplicable(a, s)) 2726 log.error(a.pos(), "annotation.type.not.applicable"); 2727 2728 if (a.annotationType.type.tsym == syms.overrideType.tsym) { 2729 if (!isOverrider(s)) 2730 log.error(a.pos(), "method.does.not.override.superclass"); 2731 } 2732 2733 if (a.annotationType.type.tsym == syms.functionalInterfaceType.tsym) { 2734 if (s.kind != TYP) { 2735 log.error(a.pos(), "bad.functional.intf.anno"); 2736 } else { 2737 try { 2738 types.findDescriptorSymbol((TypeSymbol)s); 2739 } catch (Types.FunctionDescriptorLookupError ex) { 2740 log.error(a.pos(), "bad.functional.intf.anno.1", ex.getDiagnostic()); 2741 } 2742 } 2743 } 2744 } 2745 2746 public void validateTypeAnnotation(JCAnnotation a, boolean isTypeParameter) { 2747 Assert.checkNonNull(a.type, "annotation tree hasn't been attributed yet: " + a); 2748 validateAnnotationTree(a); 2749 2750 if (!isTypeAnnotation(a, isTypeParameter)) 2751 log.error(a.pos(), "annotation.type.not.applicable"); 2752 } 2753 2754 /** 2755 * Validate the proposed container 'repeatable' on the 2756 * annotation type symbol 's'. Report errors at position 2757 * 'pos'. 2758 * 2759 * @param s The (annotation)type declaration annotated with a @Repeatable 2760 * @param repeatable the @Repeatable on 's' 2761 * @param pos where to report errors 2762 */ 2763 public void validateRepeatable(TypeSymbol s, Attribute.Compound repeatable, DiagnosticPosition pos) { 2764 Assert.check(types.isSameType(repeatable.type, syms.repeatableType)); 2765 2766 Type t = null; 2767 List<Pair<MethodSymbol,Attribute>> l = repeatable.values; 2768 if (!l.isEmpty()) { 2769 Assert.check(l.head.fst.name == names.value); 2770 t = ((Attribute.Class)l.head.snd).getValue(); 2771 } 2772 2773 if (t == null) { 2774 // errors should already have been reported during Annotate 2775 return; 2776 } 2777 2778 validateValue(t.tsym, s, pos); 2779 validateRetention(t.tsym, s, pos); 2780 validateDocumented(t.tsym, s, pos); 2781 validateInherited(t.tsym, s, pos); 2782 validateTarget(t.tsym, s, pos); 2783 validateDefault(t.tsym, s, pos); 2784 } 2785 2786 private void validateValue(TypeSymbol container, TypeSymbol contained, DiagnosticPosition pos) { 2787 Scope.Entry e = container.members().lookup(names.value); 2788 if (e.scope != null && e.sym.kind == MTH) { 2789 MethodSymbol m = (MethodSymbol) e.sym; 2790 Type ret = m.getReturnType(); 2791 if (!(ret.hasTag(ARRAY) && types.isSameType(((ArrayType)ret).elemtype, contained.type))) { 2792 log.error(pos, "invalid.repeatable.annotation.value.return", 2793 container, ret, types.makeArrayType(contained.type)); 2794 } 2795 } else { 2796 log.error(pos, "invalid.repeatable.annotation.no.value", container); 2797 } 2798 } 2799 2800 private void validateRetention(Symbol container, Symbol contained, DiagnosticPosition pos) { 2801 Attribute.RetentionPolicy containerRetention = types.getRetention(container); 2802 Attribute.RetentionPolicy containedRetention = types.getRetention(contained); 2803 2804 boolean error = false; 2805 switch (containedRetention) { 2806 case RUNTIME: 2807 if (containerRetention != Attribute.RetentionPolicy.RUNTIME) { 2808 error = true; 2809 } 2810 break; 2811 case CLASS: 2812 if (containerRetention == Attribute.RetentionPolicy.SOURCE) { 2813 error = true; 2814 } 2815 } 2816 if (error ) { 2817 log.error(pos, "invalid.repeatable.annotation.retention", 2818 container, containerRetention, 2819 contained, containedRetention); 2820 } 2821 } 2822 2823 private void validateDocumented(Symbol container, Symbol contained, DiagnosticPosition pos) { 2824 if (contained.attribute(syms.documentedType.tsym) != null) { 2825 if (container.attribute(syms.documentedType.tsym) == null) { 2826 log.error(pos, "invalid.repeatable.annotation.not.documented", container, contained); 2827 } 2828 } 2829 } 2830 2831 private void validateInherited(Symbol container, Symbol contained, DiagnosticPosition pos) { 2832 if (contained.attribute(syms.inheritedType.tsym) != null) { 2833 if (container.attribute(syms.inheritedType.tsym) == null) { 2834 log.error(pos, "invalid.repeatable.annotation.not.inherited", container, contained); 2835 } 2836 } 2837 } 2838 2839 private void validateTarget(Symbol container, Symbol contained, DiagnosticPosition pos) { 2840 // The set of targets the container is applicable to must be a subset 2841 // (with respect to annotation target semantics) of the set of targets 2842 // the contained is applicable to. The target sets may be implicit or 2843 // explicit. 2844 2845 Set<Name> containerTargets; 2846 Attribute.Array containerTarget = getAttributeTargetAttribute(container); 2847 if (containerTarget == null) { 2848 containerTargets = getDefaultTargetSet(); 2849 } else { 2850 containerTargets = new HashSet<Name>(); 2851 for (Attribute app : containerTarget.values) { 2852 if (!(app instanceof Attribute.Enum)) { 2853 continue; // recovery 2854 } 2855 Attribute.Enum e = (Attribute.Enum)app; 2856 containerTargets.add(e.value.name); 2857 } 2858 } 2859 2860 Set<Name> containedTargets; 2861 Attribute.Array containedTarget = getAttributeTargetAttribute(contained); 2862 if (containedTarget == null) { 2863 containedTargets = getDefaultTargetSet(); 2864 } else { 2865 containedTargets = new HashSet<Name>(); 2866 for (Attribute app : containedTarget.values) { 2867 if (!(app instanceof Attribute.Enum)) { 2868 continue; // recovery 2869 } 2870 Attribute.Enum e = (Attribute.Enum)app; 2871 containedTargets.add(e.value.name); 2872 } 2873 } 2874 2875 if (!isTargetSubsetOf(containerTargets, containedTargets)) { 2876 log.error(pos, "invalid.repeatable.annotation.incompatible.target", container, contained); 2877 } 2878 } 2879 2880 /* get a set of names for the default target */ 2881 private Set<Name> getDefaultTargetSet() { 2882 if (defaultTargets == null) { 2883 Set<Name> targets = new HashSet<Name>(); 2884 targets.add(names.ANNOTATION_TYPE); 2885 targets.add(names.CONSTRUCTOR); 2886 targets.add(names.FIELD); 2887 targets.add(names.LOCAL_VARIABLE); 2888 targets.add(names.METHOD); 2889 targets.add(names.PACKAGE); 2890 targets.add(names.PARAMETER); 2891 targets.add(names.TYPE); 2892 2893 defaultTargets = java.util.Collections.unmodifiableSet(targets); 2894 } 2895 2896 return defaultTargets; 2897 } 2898 private Set<Name> defaultTargets; 2899 2900 2901 /** Checks that s is a subset of t, with respect to ElementType 2902 * semantics, specifically {ANNOTATION_TYPE} is a subset of {TYPE} 2903 */ 2904 private boolean isTargetSubsetOf(Set<Name> s, Set<Name> t) { 2905 // Check that all elements in s are present in t 2906 for (Name n2 : s) { 2907 boolean currentElementOk = false; 2908 for (Name n1 : t) { 2909 if (n1 == n2) { 2910 currentElementOk = true; 2911 break; 2912 } else if (n1 == names.TYPE && n2 == names.ANNOTATION_TYPE) { 2913 currentElementOk = true; 2914 break; 2915 } 2916 } 2917 if (!currentElementOk) 2918 return false; 2919 } 2920 return true; 2921 } 2922 2923 private void validateDefault(Symbol container, Symbol contained, DiagnosticPosition pos) { 2924 // validate that all other elements of containing type has defaults 2925 Scope scope = container.members(); 2926 for(Symbol elm : scope.getElements()) { 2927 if (elm.name != names.value && 2928 elm.kind == Kinds.MTH && 2929 ((MethodSymbol)elm).defaultValue == null) { 2930 log.error(pos, 2931 "invalid.repeatable.annotation.elem.nondefault", 2932 container, 2933 elm); 2934 } 2935 } 2936 } 2937 2938 /** Is s a method symbol that overrides a method in a superclass? */ 2939 boolean isOverrider(Symbol s) { 2940 if (s.kind != MTH || s.isStatic()) 2941 return false; 2942 MethodSymbol m = (MethodSymbol)s; 2943 TypeSymbol owner = (TypeSymbol)m.owner; 2944 for (Type sup : types.closure(owner.type)) { 2945 if (sup == owner.type) 2946 continue; // skip "this" 2947 Scope scope = sup.tsym.members(); 2948 for (Scope.Entry e = scope.lookup(m.name); e.scope != null; e = e.next()) { 2949 if (!e.sym.isStatic() && m.overrides(e.sym, owner, types, true)) 2950 return true; 2951 } 2952 } 2953 return false; 2954 } 2955 2956 /** Is the annotation applicable to type annotations? */ 2957 protected boolean isTypeAnnotation(JCAnnotation a, boolean isTypeParameter) { 2958 Attribute.Compound atTarget = 2959 a.annotationType.type.tsym.attribute(syms.annotationTargetType.tsym); 2960 if (atTarget == null) { 2961 // An annotation without @Target is not a type annotation. 2962 return false; 2963 } 2964 2965 Attribute atValue = atTarget.member(names.value); 2966 if (!(atValue instanceof Attribute.Array)) { 2967 return false; // error recovery 2968 } 2969 2970 Attribute.Array arr = (Attribute.Array) atValue; 2971 for (Attribute app : arr.values) { 2972 if (!(app instanceof Attribute.Enum)) { 2973 return false; // recovery 2974 } 2975 Attribute.Enum e = (Attribute.Enum) app; 2976 2977 if (e.value.name == names.TYPE_USE) 2978 return true; 2979 else if (isTypeParameter && e.value.name == names.TYPE_PARAMETER) 2980 return true; 2981 } 2982 return false; 2983 } 2984 2985 /** Is the annotation applicable to the symbol? */ 2986 boolean annotationApplicable(JCAnnotation a, Symbol s) { 2987 Attribute.Array arr = getAttributeTargetAttribute(a.annotationType.type.tsym); 2988 Name[] targets; 2989 2990 if (arr == null) { 2991 targets = defaultTargetMetaInfo(a, s); 2992 } else { 2993 // TODO: can we optimize this? 2994 targets = new Name[arr.values.length]; 2995 for (int i=0; i<arr.values.length; ++i) { 2996 Attribute app = arr.values[i]; 2997 if (!(app instanceof Attribute.Enum)) { 2998 return true; // recovery 2999 } 3000 Attribute.Enum e = (Attribute.Enum) app; 3001 targets[i] = e.value.name; 3002 } 3003 } 3004 for (Name target : targets) { 3005 if (target == names.TYPE) 3006 { if (s.kind == TYP) return true; } 3007 else if (target == names.FIELD) 3008 { if (s.kind == VAR && s.owner.kind != MTH) return true; } 3009 else if (target == names.METHOD) 3010 { if (s.kind == MTH && !s.isConstructor()) return true; } 3011 else if (target == names.PARAMETER) 3012 { if (s.kind == VAR && 3013 s.owner.kind == MTH && 3014 (s.flags() & PARAMETER) != 0) 3015 return true; 3016 } 3017 else if (target == names.CONSTRUCTOR) 3018 { if (s.kind == MTH && s.isConstructor()) return true; } 3019 else if (target == names.LOCAL_VARIABLE) 3020 { if (s.kind == VAR && s.owner.kind == MTH && 3021 (s.flags() & PARAMETER) == 0) 3022 return true; 3023 } 3024 else if (target == names.ANNOTATION_TYPE) 3025 { if (s.kind == TYP && (s.flags() & ANNOTATION) != 0) 3026 return true; 3027 } 3028 else if (target == names.PACKAGE) 3029 { if (s.kind == PCK) return true; } 3030 else if (target == names.TYPE_USE) 3031 { if (s.kind == TYP || 3032 s.kind == VAR || 3033 (s.kind == MTH && !s.isConstructor() && 3034 !s.type.getReturnType().hasTag(VOID)) || 3035 (s.kind == MTH && s.isConstructor())) 3036 return true; 3037 } 3038 else if (target == names.TYPE_PARAMETER) 3039 { if (s.kind == TYP && s.type.hasTag(TYPEVAR)) 3040 return true; 3041 } 3042 else 3043 return true; // recovery 3044 } 3045 return false; 3046 } 3047 3048 3049 Attribute.Array getAttributeTargetAttribute(Symbol s) { 3050 Attribute.Compound atTarget = 3051 s.attribute(syms.annotationTargetType.tsym); 3052 if (atTarget == null) return null; // ok, is applicable 3053 Attribute atValue = atTarget.member(names.value); 3054 if (!(atValue instanceof Attribute.Array)) return null; // error recovery 3055 return (Attribute.Array) atValue; 3056 } 3057 3058 private final Name[] dfltTargetMeta; 3059 private Name[] defaultTargetMetaInfo(JCAnnotation a, Symbol s) { 3060 return dfltTargetMeta; 3061 } 3062 3063 /** Check an annotation value. 3064 * 3065 * @param a The annotation tree to check 3066 * @return true if this annotation tree is valid, otherwise false 3067 */ 3068 public boolean validateAnnotationDeferErrors(JCAnnotation a) { 3069 boolean res = false; 3070 final Log.DiagnosticHandler diagHandler = new Log.DiscardDiagnosticHandler(log); 3071 try { 3072 res = validateAnnotation(a); 3073 } finally { 3074 log.popDiagnosticHandler(diagHandler); 3075 } 3076 return res; 3077 } 3078 3079 private boolean validateAnnotation(JCAnnotation a) { 3080 boolean isValid = true; 3081 // collect an inventory of the annotation elements 3082 Set<MethodSymbol> members = new LinkedHashSet<MethodSymbol>(); 3083 for (Scope.Entry e = a.annotationType.type.tsym.members().elems; 3084 e != null; 3085 e = e.sibling) 3086 if (e.sym.kind == MTH && e.sym.name != names.clinit && 3087 (e.sym.flags() & SYNTHETIC) == 0) 3088 members.add((MethodSymbol) e.sym); 3089 3090 // remove the ones that are assigned values 3091 for (JCTree arg : a.args) { 3092 if (!arg.hasTag(ASSIGN)) continue; // recovery 3093 JCAssign assign = (JCAssign) arg; 3094 Symbol m = TreeInfo.symbol(assign.lhs); 3095 if (m == null || m.type.isErroneous()) continue; 3096 if (!members.remove(m)) { 3097 isValid = false; 3098 log.error(assign.lhs.pos(), "annotation.duplicate.element", 3099 m.name, a.type); 3100 } 3101 } 3102 3103 // all the remaining ones better have default values 3104 List<Name> missingDefaults = List.nil(); 3105 for (MethodSymbol m : members) { 3106 if (m.defaultValue == null && !m.type.isErroneous()) { 3107 missingDefaults = missingDefaults.append(m.name); 3108 } 3109 } 3110 missingDefaults = missingDefaults.reverse(); 3111 if (missingDefaults.nonEmpty()) { 3112 isValid = false; 3113 String key = (missingDefaults.size() > 1) 3114 ? "annotation.missing.default.value.1" 3115 : "annotation.missing.default.value"; 3116 log.error(a.pos(), key, a.type, missingDefaults); 3117 } 3118 3119 // special case: java.lang.annotation.Target must not have 3120 // repeated values in its value member 3121 if (a.annotationType.type.tsym != syms.annotationTargetType.tsym || 3122 a.args.tail == null) 3123 return isValid; 3124 3125 if (!a.args.head.hasTag(ASSIGN)) return false; // error recovery 3126 JCAssign assign = (JCAssign) a.args.head; 3127 Symbol m = TreeInfo.symbol(assign.lhs); 3128 if (m.name != names.value) return false; 3129 JCTree rhs = assign.rhs; 3130 if (!rhs.hasTag(NEWARRAY)) return false; 3131 JCNewArray na = (JCNewArray) rhs; 3132 Set<Symbol> targets = new HashSet<Symbol>(); 3133 for (JCTree elem : na.elems) { 3134 if (!targets.add(TreeInfo.symbol(elem))) { 3135 isValid = false; 3136 log.error(elem.pos(), "repeated.annotation.target"); 3137 } 3138 } 3139 return isValid; 3140 } 3141 3142 void checkDeprecatedAnnotation(DiagnosticPosition pos, Symbol s) { 3143 if (allowAnnotations && 3144 lint.isEnabled(LintCategory.DEP_ANN) && 3145 (s.flags() & DEPRECATED) != 0 && 3146 !syms.deprecatedType.isErroneous() && 3147 s.attribute(syms.deprecatedType.tsym) == null) { 3148 log.warning(LintCategory.DEP_ANN, 3149 pos, "missing.deprecated.annotation"); 3150 } 3151 } 3152 3153 void checkDeprecated(final DiagnosticPosition pos, final Symbol other, final Symbol s) { 3154 if ((s.flags() & DEPRECATED) != 0 && 3155 (other.flags() & DEPRECATED) == 0 && 3156 s.outermostClass() != other.outermostClass()) { 3157 deferredLintHandler.report(new DeferredLintHandler.LintLogger() { 3158 @Override 3159 public void report() { 3160 warnDeprecated(pos, s); 3161 } 3162 }); 3163 } 3164 } 3165 3166 void checkSunAPI(final DiagnosticPosition pos, final Symbol s) { 3167 if ((s.flags() & PROPRIETARY) != 0) { 3168 deferredLintHandler.report(new DeferredLintHandler.LintLogger() { 3169 public void report() { 3170 if (enableSunApiLintControl) 3171 warnSunApi(pos, "sun.proprietary", s); 3172 else 3173 log.mandatoryWarning(pos, "sun.proprietary", s); 3174 } 3175 }); 3176 } 3177 } 3178 3179 void checkProfile(final DiagnosticPosition pos, final Symbol s) { 3180 if (profile != Profile.DEFAULT && (s.flags() & NOT_IN_PROFILE) != 0) { 3181 log.error(pos, "not.in.profile", s, profile); 3182 } 3183 } 3184 3185 /* ************************************************************************* 3186 * Check for recursive annotation elements. 3187 **************************************************************************/ 3188 3189 /** Check for cycles in the graph of annotation elements. 3190 */ 3191 void checkNonCyclicElements(JCClassDecl tree) { 3192 if ((tree.sym.flags_field & ANNOTATION) == 0) return; 3193 Assert.check((tree.sym.flags_field & LOCKED) == 0); 3194 try { 3195 tree.sym.flags_field |= LOCKED; 3196 for (JCTree def : tree.defs) { 3197 if (!def.hasTag(METHODDEF)) continue; 3198 JCMethodDecl meth = (JCMethodDecl)def; 3199 checkAnnotationResType(meth.pos(), meth.restype.type); 3200 } 3201 } finally { 3202 tree.sym.flags_field &= ~LOCKED; 3203 tree.sym.flags_field |= ACYCLIC_ANN; 3204 } 3205 } 3206 3207 void checkNonCyclicElementsInternal(DiagnosticPosition pos, TypeSymbol tsym) { 3208 if ((tsym.flags_field & ACYCLIC_ANN) != 0) 3209 return; 3210 if ((tsym.flags_field & LOCKED) != 0) { 3211 log.error(pos, "cyclic.annotation.element"); 3212 return; 3213 } 3214 try { 3215 tsym.flags_field |= LOCKED; 3216 for (Scope.Entry e = tsym.members().elems; e != null; e = e.sibling) { 3217 Symbol s = e.sym; 3218 if (s.kind != Kinds.MTH) 3219 continue; 3220 checkAnnotationResType(pos, ((MethodSymbol)s).type.getReturnType()); 3221 } 3222 } finally { 3223 tsym.flags_field &= ~LOCKED; 3224 tsym.flags_field |= ACYCLIC_ANN; 3225 } 3226 } 3227 3228 void checkAnnotationResType(DiagnosticPosition pos, Type type) { 3229 switch (type.getTag()) { 3230 case CLASS: 3231 if ((type.tsym.flags() & ANNOTATION) != 0) 3232 checkNonCyclicElementsInternal(pos, type.tsym); 3233 break; 3234 case ARRAY: 3235 checkAnnotationResType(pos, types.elemtype(type)); 3236 break; 3237 default: 3238 break; // int etc 3239 } 3240 } 3241 3242 /* ************************************************************************* 3243 * Check for cycles in the constructor call graph. 3244 **************************************************************************/ 3245 3246 /** Check for cycles in the graph of constructors calling other 3247 * constructors. 3248 */ 3249 void checkCyclicConstructors(JCClassDecl tree) { 3250 Map<Symbol,Symbol> callMap = new HashMap<Symbol, Symbol>(); 3251 3252 // enter each constructor this-call into the map 3253 for (List<JCTree> l = tree.defs; l.nonEmpty(); l = l.tail) { 3254 JCMethodInvocation app = TreeInfo.firstConstructorCall(l.head); 3255 if (app == null) continue; 3256 JCMethodDecl meth = (JCMethodDecl) l.head; 3257 if (TreeInfo.name(app.meth) == names._this) { 3258 callMap.put(meth.sym, TreeInfo.symbol(app.meth)); 3259 } else { 3260 meth.sym.flags_field |= ACYCLIC; 3261 } 3262 } 3263 3264 // Check for cycles in the map 3265 Symbol[] ctors = new Symbol[0]; 3266 ctors = callMap.keySet().toArray(ctors); 3267 for (Symbol caller : ctors) { 3268 checkCyclicConstructor(tree, caller, callMap); 3269 } 3270 } 3271 3272 /** Look in the map to see if the given constructor is part of a 3273 * call cycle. 3274 */ 3275 private void checkCyclicConstructor(JCClassDecl tree, Symbol ctor, 3276 Map<Symbol,Symbol> callMap) { 3277 if (ctor != null && (ctor.flags_field & ACYCLIC) == 0) { 3278 if ((ctor.flags_field & LOCKED) != 0) { 3279 log.error(TreeInfo.diagnosticPositionFor(ctor, tree), 3280 "recursive.ctor.invocation"); 3281 } else { 3282 ctor.flags_field |= LOCKED; 3283 checkCyclicConstructor(tree, callMap.remove(ctor), callMap); 3284 ctor.flags_field &= ~LOCKED; 3285 } 3286 ctor.flags_field |= ACYCLIC; 3287 } 3288 } 3289 3290 /* ************************************************************************* 3291 * Miscellaneous 3292 **************************************************************************/ 3293 3294 /** 3295 * Return the opcode of the operator but emit an error if it is an 3296 * error. 3297 * @param pos position for error reporting. 3298 * @param operator an operator 3299 * @param tag a tree tag 3300 * @param left type of left hand side 3301 * @param right type of right hand side 3302 */ 3303 int checkOperator(DiagnosticPosition pos, 3304 OperatorSymbol operator, 3305 JCTree.Tag tag, 3306 Type left, 3307 Type right) { 3308 if (operator.opcode == ByteCodes.error) { 3309 log.error(pos, 3310 "operator.cant.be.applied.1", 3311 treeinfo.operatorName(tag), 3312 left, right); 3313 } 3314 return operator.opcode; 3315 } 3316 3317 3318 /** 3319 * Check for division by integer constant zero 3320 * @param pos Position for error reporting. 3321 * @param operator The operator for the expression 3322 * @param operand The right hand operand for the expression 3323 */ 3324 void checkDivZero(DiagnosticPosition pos, Symbol operator, Type operand) { 3325 if (operand.constValue() != null 3326 && lint.isEnabled(LintCategory.DIVZERO) 3327 && operand.getTag().isSubRangeOf(LONG) 3328 && ((Number) (operand.constValue())).longValue() == 0) { 3329 int opc = ((OperatorSymbol)operator).opcode; 3330 if (opc == ByteCodes.idiv || opc == ByteCodes.imod 3331 || opc == ByteCodes.ldiv || opc == ByteCodes.lmod) { 3332 log.warning(LintCategory.DIVZERO, pos, "div.zero"); 3333 } 3334 } 3335 } 3336 3337 /** 3338 * Check for empty statements after if 3339 */ 3340 void checkEmptyIf(JCIf tree) { 3341 if (tree.thenpart.hasTag(SKIP) && tree.elsepart == null && 3342 lint.isEnabled(LintCategory.EMPTY)) 3343 log.warning(LintCategory.EMPTY, tree.thenpart.pos(), "empty.if"); 3344 } 3345 3346 /** Check that symbol is unique in given scope. 3347 * @param pos Position for error reporting. 3348 * @param sym The symbol. 3349 * @param s The scope. 3350 */ 3351 boolean checkUnique(DiagnosticPosition pos, Symbol sym, Scope s) { 3352 if (sym.type.isErroneous()) 3353 return true; 3354 if (sym.owner.name == names.any) return false; 3355 for (Scope.Entry e = s.lookup(sym.name); e.scope == s; e = e.next()) { 3356 if (sym != e.sym && 3357 (e.sym.flags() & CLASH) == 0 && 3358 sym.kind == e.sym.kind && 3359 sym.name != names.error && 3360 (sym.kind != MTH || 3361 types.hasSameArgs(sym.type, e.sym.type) || 3362 types.hasSameArgs(types.erasure(sym.type), types.erasure(e.sym.type)))) { 3363 if ((sym.flags() & VARARGS) != (e.sym.flags() & VARARGS)) { 3364 varargsDuplicateError(pos, sym, e.sym); 3365 return true; 3366 } else if (sym.kind == MTH && !types.hasSameArgs(sym.type, e.sym.type, false)) { 3367 duplicateErasureError(pos, sym, e.sym); 3368 sym.flags_field |= CLASH; 3369 return true; 3370 } else { 3371 duplicateError(pos, e.sym); 3372 return false; 3373 } 3374 } 3375 } 3376 return true; 3377 } 3378 3379 /** Report duplicate declaration error. 3380 */ 3381 void duplicateErasureError(DiagnosticPosition pos, Symbol sym1, Symbol sym2) { 3382 if (!sym1.type.isErroneous() && !sym2.type.isErroneous()) { 3383 log.error(pos, "name.clash.same.erasure", sym1, sym2); 3384 } 3385 } 3386 3387 /** Check that single-type import is not already imported or top-level defined, 3388 * but make an exception for two single-type imports which denote the same type. 3389 * @param pos Position for error reporting. 3390 * @param sym The symbol. 3391 * @param s The scope 3392 */ 3393 boolean checkUniqueImport(DiagnosticPosition pos, Symbol sym, Scope s) { 3394 return checkUniqueImport(pos, sym, s, false); 3395 } 3396 3397 /** Check that static single-type import is not already imported or top-level defined, 3398 * but make an exception for two single-type imports which denote the same type. 3399 * @param pos Position for error reporting. 3400 * @param sym The symbol. 3401 * @param s The scope 3402 */ 3403 boolean checkUniqueStaticImport(DiagnosticPosition pos, Symbol sym, Scope s) { 3404 return checkUniqueImport(pos, sym, s, true); 3405 } 3406 3407 /** Check that single-type import is not already imported or top-level defined, 3408 * but make an exception for two single-type imports which denote the same type. 3409 * @param pos Position for error reporting. 3410 * @param sym The symbol. 3411 * @param s The scope. 3412 * @param staticImport Whether or not this was a static import 3413 */ 3414 private boolean checkUniqueImport(DiagnosticPosition pos, Symbol sym, Scope s, boolean staticImport) { 3415 for (Scope.Entry e = s.lookup(sym.name); e.scope != null; e = e.next()) { 3416 // is encountered class entered via a class declaration? 3417 boolean isClassDecl = e.scope == s; 3418 if ((isClassDecl || sym != e.sym) && 3419 sym.kind == e.sym.kind && 3420 sym.name != names.error && 3421 (!staticImport || !e.isStaticallyImported())) { 3422 if (!e.sym.type.isErroneous()) { 3423 String what = e.sym.getSimpleName().toString(); 3424 if (!isClassDecl) { 3425 if (staticImport) 3426 log.error(pos, "already.defined.static.single.import", what); 3427 else 3428 log.error(pos, "already.defined.single.import", what); 3429 } 3430 else if (sym != e.sym) 3431 log.error(pos, "already.defined.this.unit", what); 3432 } 3433 return false; 3434 } 3435 } 3436 return true; 3437 } 3438 3439 /** Check that a qualified name is in canonical form (for import decls). 3440 */ 3441 public void checkCanonical(JCTree tree) { 3442 if (!isCanonical(tree)) 3443 log.error(tree.pos(), "import.requires.canonical", 3444 TreeInfo.symbol(tree)); 3445 } 3446 // where 3447 private boolean isCanonical(JCTree tree) { 3448 while (tree.hasTag(SELECT)) { 3449 JCFieldAccess s = (JCFieldAccess) tree; 3450 if (s.sym.owner != TreeInfo.symbol(s.selected)) 3451 return false; 3452 tree = s.selected; 3453 } 3454 return true; 3455 } 3456 3457 /** Check that an auxiliary class is not accessed from any other file than its own. 3458 */ 3459 void checkForBadAuxiliaryClassAccess(DiagnosticPosition pos, Env<AttrContext> env, ClassSymbol c) { 3460 if (lint.isEnabled(Lint.LintCategory.AUXILIARYCLASS) && 3461 (c.flags() & AUXILIARY) != 0 && 3462 rs.isAccessible(env, c) && 3463 !fileManager.isSameFile(c.sourcefile, env.toplevel.sourcefile)) 3464 { 3465 log.warning(pos, "auxiliary.class.accessed.from.outside.of.its.source.file", 3466 c, c.sourcefile); 3467 } 3468 } 3469 3470 private class ConversionWarner extends Warner { 3471 final String uncheckedKey; 3472 final Type found; 3473 final Type expected; 3474 public ConversionWarner(DiagnosticPosition pos, String uncheckedKey, Type found, Type expected) { 3475 super(pos); 3476 this.uncheckedKey = uncheckedKey; 3477 this.found = found; 3478 this.expected = expected; 3479 } 3480 3481 @Override 3482 public void warn(LintCategory lint) { 3483 boolean warned = this.warned; 3484 super.warn(lint); 3485 if (warned) return; // suppress redundant diagnostics 3486 switch (lint) { 3487 case UNCHECKED: 3488 Check.this.warnUnchecked(pos(), "prob.found.req", diags.fragment(uncheckedKey), found, expected); 3489 break; 3490 case VARARGS: 3491 if (method != null && 3492 method.attribute(syms.trustMeType.tsym) != null && 3493 isTrustMeAllowedOnMethod(method) && 3494 !types.isReifiable(method.type.getParameterTypes().last())) { 3495 Check.this.warnUnsafeVararg(pos(), "varargs.unsafe.use.varargs.param", method.params.last()); 3496 } 3497 break; 3498 default: 3499 throw new AssertionError("Unexpected lint: " + lint); 3500 } 3501 } 3502 } 3503 3504 public Warner castWarner(DiagnosticPosition pos, Type found, Type expected) { 3505 return new ConversionWarner(pos, "unchecked.cast.to.type", found, expected); 3506 } 3507 3508 public Warner convertWarner(DiagnosticPosition pos, Type found, Type expected) { 3509 return new ConversionWarner(pos, "unchecked.assign", found, expected); 3510 } 3511 }