Check.java revision 3578:b56896d30c0f
1/* 2 * Copyright (c) 1999, 2016, 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 26package com.sun.tools.javac.comp; 27 28import java.util.*; 29 30import javax.tools.JavaFileManager; 31 32import com.sun.tools.javac.code.*; 33import com.sun.tools.javac.code.Attribute.Compound; 34import com.sun.tools.javac.comp.Annotate.AnnotationTypeMetadata; 35import com.sun.tools.javac.jvm.*; 36import com.sun.tools.javac.resources.CompilerProperties.Errors; 37import com.sun.tools.javac.resources.CompilerProperties.Fragments; 38import com.sun.tools.javac.tree.*; 39import com.sun.tools.javac.util.*; 40import com.sun.tools.javac.util.JCDiagnostic.DiagnosticFlag; 41import com.sun.tools.javac.util.JCDiagnostic.DiagnosticPosition; 42import com.sun.tools.javac.util.List; 43 44import com.sun.tools.javac.code.Lint; 45import com.sun.tools.javac.code.Lint.LintCategory; 46import com.sun.tools.javac.code.Scope.WriteableScope; 47import com.sun.tools.javac.code.Type.*; 48import com.sun.tools.javac.code.Symbol.*; 49import com.sun.tools.javac.comp.DeferredAttr.DeferredAttrContext; 50import com.sun.tools.javac.comp.Infer.FreeTypeListener; 51import com.sun.tools.javac.tree.JCTree.*; 52 53import static com.sun.tools.javac.code.Flags.*; 54import static com.sun.tools.javac.code.Flags.ANNOTATION; 55import static com.sun.tools.javac.code.Flags.SYNCHRONIZED; 56import static com.sun.tools.javac.code.Kinds.*; 57import static com.sun.tools.javac.code.Kinds.Kind.*; 58import static com.sun.tools.javac.code.Scope.LookupKind.NON_RECURSIVE; 59import static com.sun.tools.javac.code.TypeTag.*; 60import static com.sun.tools.javac.code.TypeTag.WILDCARD; 61 62import static com.sun.tools.javac.tree.JCTree.Tag.*; 63 64/** Type checking helper class for the attribution phase. 65 * 66 * <p><b>This is NOT part of any supported API. 67 * If you write code that depends on this, you do so at your own risk. 68 * This code and its internal interfaces are subject to change or 69 * deletion without notice.</b> 70 */ 71public class Check { 72 protected static final Context.Key<Check> checkKey = new Context.Key<>(); 73 74 private final Names names; 75 private final Log log; 76 private final Resolve rs; 77 private final Symtab syms; 78 private final Enter enter; 79 private final DeferredAttr deferredAttr; 80 private final Infer infer; 81 private final Types types; 82 private final TypeAnnotations typeAnnotations; 83 private final JCDiagnostic.Factory diags; 84 private final JavaFileManager fileManager; 85 private final Source source; 86 private final Profile profile; 87 private final boolean warnOnAccessToSensitiveMembers; 88 89 // The set of lint options currently in effect. It is initialized 90 // from the context, and then is set/reset as needed by Attr as it 91 // visits all the various parts of the trees during attribution. 92 private Lint lint; 93 94 // The method being analyzed in Attr - it is set/reset as needed by 95 // Attr as it visits new method declarations. 96 private MethodSymbol method; 97 98 public static Check instance(Context context) { 99 Check instance = context.get(checkKey); 100 if (instance == null) 101 instance = new Check(context); 102 return instance; 103 } 104 105 protected Check(Context context) { 106 context.put(checkKey, this); 107 108 names = Names.instance(context); 109 dfltTargetMeta = new Name[] { names.PACKAGE, names.TYPE, 110 names.FIELD, names.METHOD, names.CONSTRUCTOR, 111 names.ANNOTATION_TYPE, names.LOCAL_VARIABLE, names.PARAMETER}; 112 log = Log.instance(context); 113 rs = Resolve.instance(context); 114 syms = Symtab.instance(context); 115 enter = Enter.instance(context); 116 deferredAttr = DeferredAttr.instance(context); 117 infer = Infer.instance(context); 118 types = Types.instance(context); 119 typeAnnotations = TypeAnnotations.instance(context); 120 diags = JCDiagnostic.Factory.instance(context); 121 Options options = Options.instance(context); 122 lint = Lint.instance(context); 123 fileManager = context.get(JavaFileManager.class); 124 125 source = Source.instance(context); 126 allowSimplifiedVarargs = source.allowSimplifiedVarargs(); 127 allowDefaultMethods = source.allowDefaultMethods(); 128 allowStrictMethodClashCheck = source.allowStrictMethodClashCheck(); 129 allowPrivateSafeVarargs = source.allowPrivateSafeVarargs(); 130 allowDiamondWithAnonymousClassCreation = source.allowDiamondWithAnonymousClassCreation(); 131 warnOnAccessToSensitiveMembers = options.isSet("warnOnAccessToSensitiveMembers"); 132 133 Target target = Target.instance(context); 134 syntheticNameChar = target.syntheticNameChar(); 135 136 profile = Profile.instance(context); 137 138 boolean verboseDeprecated = lint.isEnabled(LintCategory.DEPRECATION); 139 boolean verboseUnchecked = lint.isEnabled(LintCategory.UNCHECKED); 140 boolean enforceMandatoryWarnings = true; 141 142 deprecationHandler = new MandatoryWarningHandler(log, verboseDeprecated, 143 enforceMandatoryWarnings, "deprecated", LintCategory.DEPRECATION); 144 uncheckedHandler = new MandatoryWarningHandler(log, verboseUnchecked, 145 enforceMandatoryWarnings, "unchecked", LintCategory.UNCHECKED); 146 sunApiHandler = new MandatoryWarningHandler(log, false, 147 enforceMandatoryWarnings, "sunapi", null); 148 149 deferredLintHandler = DeferredLintHandler.instance(context); 150 } 151 152 /** Switch: simplified varargs enabled? 153 */ 154 boolean allowSimplifiedVarargs; 155 156 /** Switch: default methods enabled? 157 */ 158 boolean allowDefaultMethods; 159 160 /** Switch: should unrelated return types trigger a method clash? 161 */ 162 boolean allowStrictMethodClashCheck; 163 164 /** Switch: can the @SafeVarargs annotation be applied to private methods? 165 */ 166 boolean allowPrivateSafeVarargs; 167 168 /** Switch: can diamond inference be used in anonymous instance creation ? 169 */ 170 boolean allowDiamondWithAnonymousClassCreation; 171 172 /** Character for synthetic names 173 */ 174 char syntheticNameChar; 175 176 /** A table mapping flat names of all compiled classes for each module in this run 177 * to their symbols; maintained from outside. 178 */ 179 private Map<Pair<ModuleSymbol, Name>,ClassSymbol> compiled = new HashMap<>(); 180 181 /** A handler for messages about deprecated usage. 182 */ 183 private MandatoryWarningHandler deprecationHandler; 184 185 /** A handler for messages about unchecked or unsafe usage. 186 */ 187 private MandatoryWarningHandler uncheckedHandler; 188 189 /** A handler for messages about using proprietary API. 190 */ 191 private MandatoryWarningHandler sunApiHandler; 192 193 /** A handler for deferred lint warnings. 194 */ 195 private DeferredLintHandler deferredLintHandler; 196 197/* ************************************************************************* 198 * Errors and Warnings 199 **************************************************************************/ 200 201 Lint setLint(Lint newLint) { 202 Lint prev = lint; 203 lint = newLint; 204 return prev; 205 } 206 207 MethodSymbol setMethod(MethodSymbol newMethod) { 208 MethodSymbol prev = method; 209 method = newMethod; 210 return prev; 211 } 212 213 /** Warn about deprecated symbol. 214 * @param pos Position to be used for error reporting. 215 * @param sym The deprecated symbol. 216 */ 217 void warnDeprecated(DiagnosticPosition pos, Symbol sym) { 218 if (!lint.isSuppressed(LintCategory.DEPRECATION)) 219 deprecationHandler.report(pos, "has.been.deprecated", sym, sym.location()); 220 } 221 222 /** Warn about unchecked operation. 223 * @param pos Position to be used for error reporting. 224 * @param msg A string describing the problem. 225 */ 226 public void warnUnchecked(DiagnosticPosition pos, String msg, Object... args) { 227 if (!lint.isSuppressed(LintCategory.UNCHECKED)) 228 uncheckedHandler.report(pos, msg, args); 229 } 230 231 /** Warn about unsafe vararg method decl. 232 * @param pos Position to be used for error reporting. 233 */ 234 void warnUnsafeVararg(DiagnosticPosition pos, String key, Object... args) { 235 if (lint.isEnabled(LintCategory.VARARGS) && allowSimplifiedVarargs) 236 log.warning(LintCategory.VARARGS, pos, key, args); 237 } 238 239 public void warnStatic(DiagnosticPosition pos, String msg, Object... args) { 240 if (lint.isEnabled(LintCategory.STATIC)) 241 log.warning(LintCategory.STATIC, pos, msg, args); 242 } 243 244 /** Warn about division by integer constant zero. 245 * @param pos Position to be used for error reporting. 246 */ 247 void warnDivZero(DiagnosticPosition pos) { 248 if (lint.isEnabled(LintCategory.DIVZERO)) 249 log.warning(LintCategory.DIVZERO, pos, "div.zero"); 250 } 251 252 /** 253 * Report any deferred diagnostics. 254 */ 255 public void reportDeferredDiagnostics() { 256 deprecationHandler.reportDeferredDiagnostic(); 257 uncheckedHandler.reportDeferredDiagnostic(); 258 sunApiHandler.reportDeferredDiagnostic(); 259 } 260 261 262 /** Report a failure to complete a class. 263 * @param pos Position to be used for error reporting. 264 * @param ex The failure to report. 265 */ 266 public Type completionError(DiagnosticPosition pos, CompletionFailure ex) { 267 log.error(JCDiagnostic.DiagnosticFlag.NON_DEFERRABLE, pos, "cant.access", ex.sym, ex.getDetailValue()); 268 if (ex instanceof ClassFinder.BadClassFile) throw new Abort(); 269 else return syms.errType; 270 } 271 272 /** Report an error that wrong type tag was found. 273 * @param pos Position to be used for error reporting. 274 * @param required An internationalized string describing the type tag 275 * required. 276 * @param found The type that was found. 277 */ 278 Type typeTagError(DiagnosticPosition pos, Object required, Object found) { 279 // this error used to be raised by the parser, 280 // but has been delayed to this point: 281 if (found instanceof Type && ((Type)found).hasTag(VOID)) { 282 log.error(pos, "illegal.start.of.type"); 283 return syms.errType; 284 } 285 log.error(pos, "type.found.req", found, required); 286 return types.createErrorType(found instanceof Type ? (Type)found : syms.errType); 287 } 288 289 /** Report an error that symbol cannot be referenced before super 290 * has been called. 291 * @param pos Position to be used for error reporting. 292 * @param sym The referenced symbol. 293 */ 294 void earlyRefError(DiagnosticPosition pos, Symbol sym) { 295 log.error(pos, "cant.ref.before.ctor.called", sym); 296 } 297 298 /** Report duplicate declaration error. 299 */ 300 void duplicateError(DiagnosticPosition pos, Symbol sym) { 301 if (!sym.type.isErroneous()) { 302 Symbol location = sym.location(); 303 if (location.kind == MTH && 304 ((MethodSymbol)location).isStaticOrInstanceInit()) { 305 log.error(pos, "already.defined.in.clinit", kindName(sym), sym, 306 kindName(sym.location()), kindName(sym.location().enclClass()), 307 sym.location().enclClass()); 308 } else { 309 log.error(pos, "already.defined", kindName(sym), sym, 310 kindName(sym.location()), sym.location()); 311 } 312 } 313 } 314 315 /** Report array/varargs duplicate declaration 316 */ 317 void varargsDuplicateError(DiagnosticPosition pos, Symbol sym1, Symbol sym2) { 318 if (!sym1.type.isErroneous() && !sym2.type.isErroneous()) { 319 log.error(pos, "array.and.varargs", sym1, sym2, sym2.location()); 320 } 321 } 322 323/* ************************************************************************ 324 * duplicate declaration checking 325 *************************************************************************/ 326 327 /** Check that variable does not hide variable with same name in 328 * immediately enclosing local scope. 329 * @param pos Position for error reporting. 330 * @param v The symbol. 331 * @param s The scope. 332 */ 333 void checkTransparentVar(DiagnosticPosition pos, VarSymbol v, Scope s) { 334 for (Symbol sym : s.getSymbolsByName(v.name)) { 335 if (sym.owner != v.owner) break; 336 if (sym.kind == VAR && 337 sym.owner.kind.matches(KindSelector.VAL_MTH) && 338 v.name != names.error) { 339 duplicateError(pos, sym); 340 return; 341 } 342 } 343 } 344 345 /** Check that a class or interface does not hide a class or 346 * interface with same name in immediately enclosing local scope. 347 * @param pos Position for error reporting. 348 * @param c The symbol. 349 * @param s The scope. 350 */ 351 void checkTransparentClass(DiagnosticPosition pos, ClassSymbol c, Scope s) { 352 for (Symbol sym : s.getSymbolsByName(c.name)) { 353 if (sym.owner != c.owner) break; 354 if (sym.kind == TYP && !sym.type.hasTag(TYPEVAR) && 355 sym.owner.kind.matches(KindSelector.VAL_MTH) && 356 c.name != names.error) { 357 duplicateError(pos, sym); 358 return; 359 } 360 } 361 } 362 363 /** Check that class does not have the same name as one of 364 * its enclosing classes, or as a class defined in its enclosing scope. 365 * return true if class is unique in its enclosing scope. 366 * @param pos Position for error reporting. 367 * @param name The class name. 368 * @param s The enclosing scope. 369 */ 370 boolean checkUniqueClassName(DiagnosticPosition pos, Name name, Scope s) { 371 for (Symbol sym : s.getSymbolsByName(name, NON_RECURSIVE)) { 372 if (sym.kind == TYP && sym.name != names.error) { 373 duplicateError(pos, sym); 374 return false; 375 } 376 } 377 for (Symbol sym = s.owner; sym != null; sym = sym.owner) { 378 if (sym.kind == TYP && sym.name == name && sym.name != names.error) { 379 duplicateError(pos, sym); 380 return true; 381 } 382 } 383 return true; 384 } 385 386/* ************************************************************************* 387 * Class name generation 388 **************************************************************************/ 389 390 391 private Map<Pair<Name, Name>, Integer> localClassNameIndexes = new HashMap<>(); 392 393 /** Return name of local class. 394 * This is of the form {@code <enclClass> $ n <classname> } 395 * where 396 * enclClass is the flat name of the enclosing class, 397 * classname is the simple name of the local class 398 */ 399 Name localClassName(ClassSymbol c) { 400 Name enclFlatname = c.owner.enclClass().flatname; 401 String enclFlatnameStr = enclFlatname.toString(); 402 Pair<Name, Name> key = new Pair<>(enclFlatname, c.name); 403 Integer index = localClassNameIndexes.get(key); 404 for (int i = (index == null) ? 1 : index; ; i++) { 405 Name flatname = names.fromString(enclFlatnameStr 406 + syntheticNameChar + i + c.name); 407 if (getCompiled(c.packge().modle, flatname) == null) { 408 localClassNameIndexes.put(key, i + 1); 409 return flatname; 410 } 411 } 412 } 413 414 void clearLocalClassNameIndexes(ClassSymbol c) { 415 localClassNameIndexes.remove(new Pair<>( 416 c.owner.enclClass().flatname, c.name)); 417 } 418 419 public void newRound() { 420 compiled.clear(); 421 localClassNameIndexes.clear(); 422 } 423 424 public void putCompiled(ClassSymbol csym) { 425 compiled.put(Pair.of(csym.packge().modle, csym.flatname), csym); 426 } 427 428 public ClassSymbol getCompiled(ClassSymbol csym) { 429 return compiled.get(Pair.of(csym.packge().modle, csym.flatname)); 430 } 431 432 public ClassSymbol getCompiled(ModuleSymbol msym, Name flatname) { 433 return compiled.get(Pair.of(msym, flatname)); 434 } 435 436 public void removeCompiled(ClassSymbol csym) { 437 compiled.remove(Pair.of(csym.packge().modle, csym.flatname)); 438 } 439 440/* ************************************************************************* 441 * Type Checking 442 **************************************************************************/ 443 444 /** 445 * A check context is an object that can be used to perform compatibility 446 * checks - depending on the check context, meaning of 'compatibility' might 447 * vary significantly. 448 */ 449 public interface CheckContext { 450 /** 451 * Is type 'found' compatible with type 'req' in given context 452 */ 453 boolean compatible(Type found, Type req, Warner warn); 454 /** 455 * Report a check error 456 */ 457 void report(DiagnosticPosition pos, JCDiagnostic details); 458 /** 459 * Obtain a warner for this check context 460 */ 461 public Warner checkWarner(DiagnosticPosition pos, Type found, Type req); 462 463 public InferenceContext inferenceContext(); 464 465 public DeferredAttr.DeferredAttrContext deferredAttrContext(); 466 } 467 468 /** 469 * This class represent a check context that is nested within another check 470 * context - useful to check sub-expressions. The default behavior simply 471 * redirects all method calls to the enclosing check context leveraging 472 * the forwarding pattern. 473 */ 474 static class NestedCheckContext implements CheckContext { 475 CheckContext enclosingContext; 476 477 NestedCheckContext(CheckContext enclosingContext) { 478 this.enclosingContext = enclosingContext; 479 } 480 481 public boolean compatible(Type found, Type req, Warner warn) { 482 return enclosingContext.compatible(found, req, warn); 483 } 484 485 public void report(DiagnosticPosition pos, JCDiagnostic details) { 486 enclosingContext.report(pos, details); 487 } 488 489 public Warner checkWarner(DiagnosticPosition pos, Type found, Type req) { 490 return enclosingContext.checkWarner(pos, found, req); 491 } 492 493 public InferenceContext inferenceContext() { 494 return enclosingContext.inferenceContext(); 495 } 496 497 public DeferredAttrContext deferredAttrContext() { 498 return enclosingContext.deferredAttrContext(); 499 } 500 } 501 502 /** 503 * Check context to be used when evaluating assignment/return statements 504 */ 505 CheckContext basicHandler = new CheckContext() { 506 public void report(DiagnosticPosition pos, JCDiagnostic details) { 507 log.error(pos, "prob.found.req", details); 508 } 509 public boolean compatible(Type found, Type req, Warner warn) { 510 return types.isAssignable(found, req, warn); 511 } 512 513 public Warner checkWarner(DiagnosticPosition pos, Type found, Type req) { 514 return convertWarner(pos, found, req); 515 } 516 517 public InferenceContext inferenceContext() { 518 return infer.emptyContext; 519 } 520 521 public DeferredAttrContext deferredAttrContext() { 522 return deferredAttr.emptyDeferredAttrContext; 523 } 524 525 @Override 526 public String toString() { 527 return "CheckContext: basicHandler"; 528 } 529 }; 530 531 /** Check that a given type is assignable to a given proto-type. 532 * If it is, return the type, otherwise return errType. 533 * @param pos Position to be used for error reporting. 534 * @param found The type that was found. 535 * @param req The type that was required. 536 */ 537 public Type checkType(DiagnosticPosition pos, Type found, Type req) { 538 return checkType(pos, found, req, basicHandler); 539 } 540 541 Type checkType(final DiagnosticPosition pos, final Type found, final Type req, final CheckContext checkContext) { 542 final InferenceContext inferenceContext = checkContext.inferenceContext(); 543 if (inferenceContext.free(req) || inferenceContext.free(found)) { 544 inferenceContext.addFreeTypeListener(List.of(req, found), new FreeTypeListener() { 545 @Override 546 public void typesInferred(InferenceContext inferenceContext) { 547 checkType(pos, inferenceContext.asInstType(found), inferenceContext.asInstType(req), checkContext); 548 } 549 }); 550 } 551 if (req.hasTag(ERROR)) 552 return req; 553 if (req.hasTag(NONE)) 554 return found; 555 if (checkContext.compatible(found, req, checkContext.checkWarner(pos, found, req))) { 556 return found; 557 } else { 558 if (found.isNumeric() && req.isNumeric()) { 559 checkContext.report(pos, diags.fragment("possible.loss.of.precision", found, req)); 560 return types.createErrorType(found); 561 } 562 checkContext.report(pos, diags.fragment("inconvertible.types", found, req)); 563 return types.createErrorType(found); 564 } 565 } 566 567 /** Check that a given type can be cast to a given target type. 568 * Return the result of the cast. 569 * @param pos Position to be used for error reporting. 570 * @param found The type that is being cast. 571 * @param req The target type of the cast. 572 */ 573 Type checkCastable(DiagnosticPosition pos, Type found, Type req) { 574 return checkCastable(pos, found, req, basicHandler); 575 } 576 Type checkCastable(DiagnosticPosition pos, Type found, Type req, CheckContext checkContext) { 577 if (types.isCastable(found, req, castWarner(pos, found, req))) { 578 return req; 579 } else { 580 checkContext.report(pos, diags.fragment("inconvertible.types", found, req)); 581 return types.createErrorType(found); 582 } 583 } 584 585 /** Check for redundant casts (i.e. where source type is a subtype of target type) 586 * The problem should only be reported for non-292 cast 587 */ 588 public void checkRedundantCast(Env<AttrContext> env, final JCTypeCast tree) { 589 if (!tree.type.isErroneous() 590 && types.isSameType(tree.expr.type, tree.clazz.type) 591 && !(ignoreAnnotatedCasts && TreeInfo.containsTypeAnnotation(tree.clazz)) 592 && !is292targetTypeCast(tree)) { 593 deferredLintHandler.report(new DeferredLintHandler.LintLogger() { 594 @Override 595 public void report() { 596 if (lint.isEnabled(Lint.LintCategory.CAST)) 597 log.warning(Lint.LintCategory.CAST, 598 tree.pos(), "redundant.cast", tree.clazz.type); 599 } 600 }); 601 } 602 } 603 //where 604 private boolean is292targetTypeCast(JCTypeCast tree) { 605 boolean is292targetTypeCast = false; 606 JCExpression expr = TreeInfo.skipParens(tree.expr); 607 if (expr.hasTag(APPLY)) { 608 JCMethodInvocation apply = (JCMethodInvocation)expr; 609 Symbol sym = TreeInfo.symbol(apply.meth); 610 is292targetTypeCast = sym != null && 611 sym.kind == MTH && 612 (sym.flags() & HYPOTHETICAL) != 0; 613 } 614 return is292targetTypeCast; 615 } 616 617 private static final boolean ignoreAnnotatedCasts = true; 618 619 /** Check that a type is within some bounds. 620 * 621 * Used in TypeApply to verify that, e.g., X in {@code V<X>} is a valid 622 * type argument. 623 * @param a The type that should be bounded by bs. 624 * @param bound The bound. 625 */ 626 private boolean checkExtends(Type a, Type bound) { 627 if (a.isUnbound()) { 628 return true; 629 } else if (!a.hasTag(WILDCARD)) { 630 a = types.cvarUpperBound(a); 631 return types.isSubtype(a, bound); 632 } else if (a.isExtendsBound()) { 633 return types.isCastable(bound, types.wildUpperBound(a), types.noWarnings); 634 } else if (a.isSuperBound()) { 635 return !types.notSoftSubtype(types.wildLowerBound(a), bound); 636 } 637 return true; 638 } 639 640 /** Check that type is different from 'void'. 641 * @param pos Position to be used for error reporting. 642 * @param t The type to be checked. 643 */ 644 Type checkNonVoid(DiagnosticPosition pos, Type t) { 645 if (t.hasTag(VOID)) { 646 log.error(pos, "void.not.allowed.here"); 647 return types.createErrorType(t); 648 } else { 649 return t; 650 } 651 } 652 653 Type checkClassOrArrayType(DiagnosticPosition pos, Type t) { 654 if (!t.hasTag(CLASS) && !t.hasTag(ARRAY) && !t.hasTag(ERROR)) { 655 return typeTagError(pos, 656 diags.fragment("type.req.class.array"), 657 asTypeParam(t)); 658 } else { 659 return t; 660 } 661 } 662 663 /** Check that type is a class or interface type. 664 * @param pos Position to be used for error reporting. 665 * @param t The type to be checked. 666 */ 667 Type checkClassType(DiagnosticPosition pos, Type t) { 668 if (!t.hasTag(CLASS) && !t.hasTag(ERROR)) { 669 return typeTagError(pos, 670 diags.fragment("type.req.class"), 671 asTypeParam(t)); 672 } else { 673 return t; 674 } 675 } 676 //where 677 private Object asTypeParam(Type t) { 678 return (t.hasTag(TYPEVAR)) 679 ? diags.fragment("type.parameter", t) 680 : t; 681 } 682 683 /** Check that type is a valid qualifier for a constructor reference expression 684 */ 685 Type checkConstructorRefType(DiagnosticPosition pos, Type t) { 686 t = checkClassOrArrayType(pos, t); 687 if (t.hasTag(CLASS)) { 688 if ((t.tsym.flags() & (ABSTRACT | INTERFACE)) != 0) { 689 log.error(pos, "abstract.cant.be.instantiated", t.tsym); 690 t = types.createErrorType(t); 691 } else if ((t.tsym.flags() & ENUM) != 0) { 692 log.error(pos, "enum.cant.be.instantiated"); 693 t = types.createErrorType(t); 694 } else { 695 t = checkClassType(pos, t, true); 696 } 697 } else if (t.hasTag(ARRAY)) { 698 if (!types.isReifiable(((ArrayType)t).elemtype)) { 699 log.error(pos, "generic.array.creation"); 700 t = types.createErrorType(t); 701 } 702 } 703 return t; 704 } 705 706 /** Check that type is a class or interface type. 707 * @param pos Position to be used for error reporting. 708 * @param t The type to be checked. 709 * @param noBounds True if type bounds are illegal here. 710 */ 711 Type checkClassType(DiagnosticPosition pos, Type t, boolean noBounds) { 712 t = checkClassType(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 reference type, i.e. a class, interface or array type 727 * or a type variable. 728 * @param pos Position to be used for error reporting. 729 * @param t The type to be checked. 730 */ 731 Type checkRefType(DiagnosticPosition pos, Type t) { 732 if (t.isReference()) 733 return t; 734 else 735 return typeTagError(pos, 736 diags.fragment("type.req.ref"), 737 t); 738 } 739 740 /** Check that each type is a reference type, i.e. a class, interface or array type 741 * or a type variable. 742 * @param trees Original trees, used for error reporting. 743 * @param types The types to be checked. 744 */ 745 List<Type> checkRefTypes(List<JCExpression> trees, List<Type> types) { 746 List<JCExpression> tl = trees; 747 for (List<Type> l = types; l.nonEmpty(); l = l.tail) { 748 l.head = checkRefType(tl.head.pos(), l.head); 749 tl = tl.tail; 750 } 751 return types; 752 } 753 754 /** Check that type is a null or reference type. 755 * @param pos Position to be used for error reporting. 756 * @param t The type to be checked. 757 */ 758 Type checkNullOrRefType(DiagnosticPosition pos, Type t) { 759 if (t.isReference() || t.hasTag(BOT)) 760 return t; 761 else 762 return typeTagError(pos, 763 diags.fragment("type.req.ref"), 764 t); 765 } 766 767 /** Check that flag set does not contain elements of two conflicting sets. s 768 * Return true if it doesn't. 769 * @param pos Position to be used for error reporting. 770 * @param flags The set of flags to be checked. 771 * @param set1 Conflicting flags set #1. 772 * @param set2 Conflicting flags set #2. 773 */ 774 boolean checkDisjoint(DiagnosticPosition pos, long flags, long set1, long set2) { 775 if ((flags & set1) != 0 && (flags & set2) != 0) { 776 log.error(pos, 777 "illegal.combination.of.modifiers", 778 asFlagSet(TreeInfo.firstFlag(flags & set1)), 779 asFlagSet(TreeInfo.firstFlag(flags & set2))); 780 return false; 781 } else 782 return true; 783 } 784 785 /** Check that usage of diamond operator is correct (i.e. diamond should not 786 * be used with non-generic classes or in anonymous class creation expressions) 787 */ 788 Type checkDiamond(JCNewClass tree, Type t) { 789 if (!TreeInfo.isDiamond(tree) || 790 t.isErroneous()) { 791 return checkClassType(tree.clazz.pos(), t, true); 792 } else if (tree.def != null && !allowDiamondWithAnonymousClassCreation) { 793 log.error(tree.clazz.pos(), 794 Errors.CantApplyDiamond1(t, Fragments.DiamondAndAnonClassNotSupportedInSource(source.name))); 795 return types.createErrorType(t); 796 } else if (t.tsym.type.getTypeArguments().isEmpty()) { 797 log.error(tree.clazz.pos(), 798 "cant.apply.diamond.1", 799 t, diags.fragment("diamond.non.generic", t)); 800 return types.createErrorType(t); 801 } else if (tree.typeargs != null && 802 tree.typeargs.nonEmpty()) { 803 log.error(tree.clazz.pos(), 804 "cant.apply.diamond.1", 805 t, diags.fragment("diamond.and.explicit.params", t)); 806 return types.createErrorType(t); 807 } else { 808 return t; 809 } 810 } 811 812 /** Check that the type inferred using the diamond operator does not contain 813 * non-denotable types such as captured types or intersection types. 814 * @param t the type inferred using the diamond operator 815 * @return the (possibly empty) list of non-denotable types. 816 */ 817 List<Type> checkDiamondDenotable(ClassType t) { 818 ListBuffer<Type> buf = new ListBuffer<>(); 819 for (Type arg : t.allparams()) { 820 if (!diamondTypeChecker.visit(arg, null)) { 821 buf.append(arg); 822 } 823 } 824 return buf.toList(); 825 } 826 // where 827 828 /** diamondTypeChecker: A type visitor that descends down the given type looking for non-denotable 829 * types. The visit methods return false as soon as a non-denotable type is encountered and true 830 * otherwise. 831 */ 832 private static final Types.SimpleVisitor<Boolean, Void> diamondTypeChecker = new Types.SimpleVisitor<Boolean, Void>() { 833 @Override 834 public Boolean visitType(Type t, Void s) { 835 return true; 836 } 837 @Override 838 public Boolean visitClassType(ClassType t, Void s) { 839 if (t.isCompound()) { 840 return false; 841 } 842 for (Type targ : t.allparams()) { 843 if (!visit(targ, s)) { 844 return false; 845 } 846 } 847 return true; 848 } 849 850 @Override 851 public Boolean visitTypeVar(TypeVar t, Void s) { 852 /* Any type variable mentioned in the inferred type must have been declared as a type parameter 853 (i.e cannot have been produced by inference (18.4)) 854 */ 855 return t.tsym.owner.type.getTypeArguments().contains(t); 856 } 857 858 @Override 859 public Boolean visitCapturedType(CapturedType t, Void s) { 860 /* Any type variable mentioned in the inferred type must have been declared as a type parameter 861 (i.e cannot have been produced by capture conversion (5.1.10)) 862 */ 863 return false; 864 } 865 866 @Override 867 public Boolean visitArrayType(ArrayType t, Void s) { 868 return visit(t.elemtype, s); 869 } 870 871 @Override 872 public Boolean visitWildcardType(WildcardType t, Void s) { 873 return visit(t.type, s); 874 } 875 }; 876 877 void checkVarargsMethodDecl(Env<AttrContext> env, JCMethodDecl tree) { 878 MethodSymbol m = tree.sym; 879 if (!allowSimplifiedVarargs) return; 880 boolean hasTrustMeAnno = m.attribute(syms.trustMeType.tsym) != null; 881 Type varargElemType = null; 882 if (m.isVarArgs()) { 883 varargElemType = types.elemtype(tree.params.last().type); 884 } 885 if (hasTrustMeAnno && !isTrustMeAllowedOnMethod(m)) { 886 if (varargElemType != null) { 887 log.error(tree, 888 "varargs.invalid.trustme.anno", 889 syms.trustMeType.tsym, 890 allowPrivateSafeVarargs ? 891 diags.fragment("varargs.trustme.on.virtual.varargs", m) : 892 diags.fragment("varargs.trustme.on.virtual.varargs.final.only", m)); 893 } else { 894 log.error(tree, 895 "varargs.invalid.trustme.anno", 896 syms.trustMeType.tsym, 897 diags.fragment("varargs.trustme.on.non.varargs.meth", m)); 898 } 899 } else if (hasTrustMeAnno && varargElemType != null && 900 types.isReifiable(varargElemType)) { 901 warnUnsafeVararg(tree, 902 "varargs.redundant.trustme.anno", 903 syms.trustMeType.tsym, 904 diags.fragment("varargs.trustme.on.reifiable.varargs", varargElemType)); 905 } 906 else if (!hasTrustMeAnno && varargElemType != null && 907 !types.isReifiable(varargElemType)) { 908 warnUnchecked(tree.params.head.pos(), "unchecked.varargs.non.reifiable.type", varargElemType); 909 } 910 } 911 //where 912 private boolean isTrustMeAllowedOnMethod(Symbol s) { 913 return (s.flags() & VARARGS) != 0 && 914 (s.isConstructor() || 915 (s.flags() & (STATIC | FINAL | 916 (allowPrivateSafeVarargs ? PRIVATE : 0) )) != 0); 917 } 918 919 Type checkMethod(final Type mtype, 920 final Symbol sym, 921 final Env<AttrContext> env, 922 final List<JCExpression> argtrees, 923 final List<Type> argtypes, 924 final boolean useVarargs, 925 InferenceContext inferenceContext) { 926 // System.out.println("call : " + env.tree); 927 // System.out.println("method : " + owntype); 928 // System.out.println("actuals: " + argtypes); 929 if (inferenceContext.free(mtype)) { 930 inferenceContext.addFreeTypeListener(List.of(mtype), new FreeTypeListener() { 931 public void typesInferred(InferenceContext inferenceContext) { 932 checkMethod(inferenceContext.asInstType(mtype), sym, env, argtrees, argtypes, useVarargs, inferenceContext); 933 } 934 }); 935 return mtype; 936 } 937 Type owntype = mtype; 938 List<Type> formals = owntype.getParameterTypes(); 939 List<Type> nonInferred = sym.type.getParameterTypes(); 940 if (nonInferred.length() != formals.length()) nonInferred = formals; 941 Type last = useVarargs ? formals.last() : null; 942 if (sym.name == names.init && sym.owner == syms.enumSym) { 943 formals = formals.tail.tail; 944 nonInferred = nonInferred.tail.tail; 945 } 946 List<JCExpression> args = argtrees; 947 if (args != null) { 948 //this is null when type-checking a method reference 949 while (formals.head != last) { 950 JCTree arg = args.head; 951 Warner warn = convertWarner(arg.pos(), arg.type, nonInferred.head); 952 assertConvertible(arg, arg.type, formals.head, warn); 953 args = args.tail; 954 formals = formals.tail; 955 nonInferred = nonInferred.tail; 956 } 957 if (useVarargs) { 958 Type varArg = types.elemtype(last); 959 while (args.tail != null) { 960 JCTree arg = args.head; 961 Warner warn = convertWarner(arg.pos(), arg.type, varArg); 962 assertConvertible(arg, arg.type, varArg, warn); 963 args = args.tail; 964 } 965 } else if ((sym.flags() & (VARARGS | SIGNATURE_POLYMORPHIC)) == VARARGS) { 966 // non-varargs call to varargs method 967 Type varParam = owntype.getParameterTypes().last(); 968 Type lastArg = argtypes.last(); 969 if (types.isSubtypeUnchecked(lastArg, types.elemtype(varParam)) && 970 !types.isSameType(types.erasure(varParam), types.erasure(lastArg))) 971 log.warning(argtrees.last().pos(), "inexact.non-varargs.call", 972 types.elemtype(varParam), varParam); 973 } 974 } 975 if (useVarargs) { 976 Type argtype = owntype.getParameterTypes().last(); 977 if (!types.isReifiable(argtype) && 978 (!allowSimplifiedVarargs || 979 sym.baseSymbol().attribute(syms.trustMeType.tsym) == null || 980 !isTrustMeAllowedOnMethod(sym))) { 981 warnUnchecked(env.tree.pos(), 982 "unchecked.generic.array.creation", 983 argtype); 984 } 985 if ((sym.baseSymbol().flags() & SIGNATURE_POLYMORPHIC) == 0) { 986 TreeInfo.setVarargsElement(env.tree, types.elemtype(argtype)); 987 } 988 } 989 return owntype; 990 } 991 //where 992 private void assertConvertible(JCTree tree, Type actual, Type formal, Warner warn) { 993 if (types.isConvertible(actual, formal, warn)) 994 return; 995 996 if (formal.isCompound() 997 && types.isSubtype(actual, types.supertype(formal)) 998 && types.isSubtypeUnchecked(actual, types.interfaces(formal), warn)) 999 return; 1000 } 1001 1002 /** 1003 * Check that type 't' is a valid instantiation of a generic class 1004 * (see JLS 4.5) 1005 * 1006 * @param t class type to be checked 1007 * @return true if 't' is well-formed 1008 */ 1009 public boolean checkValidGenericType(Type t) { 1010 return firstIncompatibleTypeArg(t) == null; 1011 } 1012 //WHERE 1013 private Type firstIncompatibleTypeArg(Type type) { 1014 List<Type> formals = type.tsym.type.allparams(); 1015 List<Type> actuals = type.allparams(); 1016 List<Type> args = type.getTypeArguments(); 1017 List<Type> forms = type.tsym.type.getTypeArguments(); 1018 ListBuffer<Type> bounds_buf = new ListBuffer<>(); 1019 1020 // For matching pairs of actual argument types `a' and 1021 // formal type parameters with declared bound `b' ... 1022 while (args.nonEmpty() && forms.nonEmpty()) { 1023 // exact type arguments needs to know their 1024 // bounds (for upper and lower bound 1025 // calculations). So we create new bounds where 1026 // type-parameters are replaced with actuals argument types. 1027 bounds_buf.append(types.subst(forms.head.getUpperBound(), formals, actuals)); 1028 args = args.tail; 1029 forms = forms.tail; 1030 } 1031 1032 args = type.getTypeArguments(); 1033 List<Type> tvars_cap = types.substBounds(formals, 1034 formals, 1035 types.capture(type).allparams()); 1036 while (args.nonEmpty() && tvars_cap.nonEmpty()) { 1037 // Let the actual arguments know their bound 1038 args.head.withTypeVar((TypeVar)tvars_cap.head); 1039 args = args.tail; 1040 tvars_cap = tvars_cap.tail; 1041 } 1042 1043 args = type.getTypeArguments(); 1044 List<Type> bounds = bounds_buf.toList(); 1045 1046 while (args.nonEmpty() && bounds.nonEmpty()) { 1047 Type actual = args.head; 1048 if (!isTypeArgErroneous(actual) && 1049 !bounds.head.isErroneous() && 1050 !checkExtends(actual, bounds.head)) { 1051 return args.head; 1052 } 1053 args = args.tail; 1054 bounds = bounds.tail; 1055 } 1056 1057 args = type.getTypeArguments(); 1058 bounds = bounds_buf.toList(); 1059 1060 for (Type arg : types.capture(type).getTypeArguments()) { 1061 if (arg.hasTag(TYPEVAR) && 1062 arg.getUpperBound().isErroneous() && 1063 !bounds.head.isErroneous() && 1064 !isTypeArgErroneous(args.head)) { 1065 return args.head; 1066 } 1067 bounds = bounds.tail; 1068 args = args.tail; 1069 } 1070 1071 return null; 1072 } 1073 //where 1074 boolean isTypeArgErroneous(Type t) { 1075 return isTypeArgErroneous.visit(t); 1076 } 1077 1078 Types.UnaryVisitor<Boolean> isTypeArgErroneous = new Types.UnaryVisitor<Boolean>() { 1079 public Boolean visitType(Type t, Void s) { 1080 return t.isErroneous(); 1081 } 1082 @Override 1083 public Boolean visitTypeVar(TypeVar t, Void s) { 1084 return visit(t.getUpperBound()); 1085 } 1086 @Override 1087 public Boolean visitCapturedType(CapturedType t, Void s) { 1088 return visit(t.getUpperBound()) || 1089 visit(t.getLowerBound()); 1090 } 1091 @Override 1092 public Boolean visitWildcardType(WildcardType t, Void s) { 1093 return visit(t.type); 1094 } 1095 }; 1096 1097 /** Check that given modifiers are legal for given symbol and 1098 * return modifiers together with any implicit modifiers for that symbol. 1099 * Warning: we can't use flags() here since this method 1100 * is called during class enter, when flags() would cause a premature 1101 * completion. 1102 * @param pos Position to be used for error reporting. 1103 * @param flags The set of modifiers given in a definition. 1104 * @param sym The defined symbol. 1105 */ 1106 long checkFlags(DiagnosticPosition pos, long flags, Symbol sym, JCTree tree) { 1107 long mask; 1108 long implicit = 0; 1109 1110 switch (sym.kind) { 1111 case VAR: 1112 if (TreeInfo.isReceiverParam(tree)) 1113 mask = ReceiverParamFlags; 1114 else if (sym.owner.kind != TYP) 1115 mask = LocalVarFlags; 1116 else if ((sym.owner.flags_field & INTERFACE) != 0) 1117 mask = implicit = InterfaceVarFlags; 1118 else 1119 mask = VarFlags; 1120 break; 1121 case MTH: 1122 if (sym.name == names.init) { 1123 if ((sym.owner.flags_field & ENUM) != 0) { 1124 // enum constructors cannot be declared public or 1125 // protected and must be implicitly or explicitly 1126 // private 1127 implicit = PRIVATE; 1128 mask = PRIVATE; 1129 } else 1130 mask = ConstructorFlags; 1131 } else if ((sym.owner.flags_field & INTERFACE) != 0) { 1132 if ((sym.owner.flags_field & ANNOTATION) != 0) { 1133 mask = AnnotationTypeElementMask; 1134 implicit = PUBLIC | ABSTRACT; 1135 } else if ((flags & (DEFAULT | STATIC | PRIVATE)) != 0) { 1136 mask = InterfaceMethodMask; 1137 implicit = (flags & PRIVATE) != 0 ? 0 : PUBLIC; 1138 if ((flags & DEFAULT) != 0) { 1139 implicit |= ABSTRACT; 1140 } 1141 } else { 1142 mask = implicit = InterfaceMethodFlags; 1143 } 1144 } else { 1145 mask = MethodFlags; 1146 } 1147 // Imply STRICTFP if owner has STRICTFP set. 1148 if (((flags|implicit) & Flags.ABSTRACT) == 0 || 1149 ((flags) & Flags.DEFAULT) != 0) 1150 implicit |= sym.owner.flags_field & STRICTFP; 1151 break; 1152 case TYP: 1153 if (sym.isLocal()) { 1154 mask = LocalClassFlags; 1155 if ((sym.owner.flags_field & STATIC) == 0 && 1156 (flags & ENUM) != 0) 1157 log.error(pos, "enums.must.be.static"); 1158 } else if (sym.owner.kind == TYP) { 1159 mask = MemberClassFlags; 1160 if (sym.owner.owner.kind == PCK || 1161 (sym.owner.flags_field & STATIC) != 0) 1162 mask |= STATIC; 1163 else if ((flags & ENUM) != 0) 1164 log.error(pos, "enums.must.be.static"); 1165 // Nested interfaces and enums are always STATIC (Spec ???) 1166 if ((flags & (INTERFACE | ENUM)) != 0 ) implicit = STATIC; 1167 } else { 1168 mask = ClassFlags; 1169 } 1170 // Interfaces are always ABSTRACT 1171 if ((flags & INTERFACE) != 0) implicit |= ABSTRACT; 1172 1173 if ((flags & ENUM) != 0) { 1174 // enums can't be declared abstract or final 1175 mask &= ~(ABSTRACT | FINAL); 1176 implicit |= implicitEnumFinalFlag(tree); 1177 } 1178 // Imply STRICTFP if owner has STRICTFP set. 1179 implicit |= sym.owner.flags_field & STRICTFP; 1180 break; 1181 default: 1182 throw new AssertionError(); 1183 } 1184 long illegal = flags & ExtendedStandardFlags & ~mask; 1185 if (illegal != 0) { 1186 if ((illegal & INTERFACE) != 0) { 1187 log.error(pos, "intf.not.allowed.here"); 1188 mask |= INTERFACE; 1189 } 1190 else { 1191 log.error(pos, 1192 "mod.not.allowed.here", asFlagSet(illegal)); 1193 } 1194 } 1195 else if ((sym.kind == TYP || 1196 // ISSUE: Disallowing abstract&private is no longer appropriate 1197 // in the presence of inner classes. Should it be deleted here? 1198 checkDisjoint(pos, flags, 1199 ABSTRACT, 1200 PRIVATE | STATIC | DEFAULT)) 1201 && 1202 checkDisjoint(pos, flags, 1203 STATIC | PRIVATE, 1204 DEFAULT) 1205 && 1206 checkDisjoint(pos, flags, 1207 ABSTRACT | INTERFACE, 1208 FINAL | NATIVE | SYNCHRONIZED) 1209 && 1210 checkDisjoint(pos, flags, 1211 PUBLIC, 1212 PRIVATE | PROTECTED) 1213 && 1214 checkDisjoint(pos, flags, 1215 PRIVATE, 1216 PUBLIC | PROTECTED) 1217 && 1218 checkDisjoint(pos, flags, 1219 FINAL, 1220 VOLATILE) 1221 && 1222 (sym.kind == TYP || 1223 checkDisjoint(pos, flags, 1224 ABSTRACT | NATIVE, 1225 STRICTFP))) { 1226 // skip 1227 } 1228 return flags & (mask | ~ExtendedStandardFlags) | implicit; 1229 } 1230 1231 1232 /** Determine if this enum should be implicitly final. 1233 * 1234 * If the enum has no specialized enum contants, it is final. 1235 * 1236 * If the enum does have specialized enum contants, it is 1237 * <i>not</i> final. 1238 */ 1239 private long implicitEnumFinalFlag(JCTree tree) { 1240 if (!tree.hasTag(CLASSDEF)) return 0; 1241 class SpecialTreeVisitor extends JCTree.Visitor { 1242 boolean specialized; 1243 SpecialTreeVisitor() { 1244 this.specialized = false; 1245 } 1246 1247 @Override 1248 public void visitTree(JCTree tree) { /* no-op */ } 1249 1250 @Override 1251 public void visitVarDef(JCVariableDecl tree) { 1252 if ((tree.mods.flags & ENUM) != 0) { 1253 if (tree.init instanceof JCNewClass && 1254 ((JCNewClass) tree.init).def != null) { 1255 specialized = true; 1256 } 1257 } 1258 } 1259 } 1260 1261 SpecialTreeVisitor sts = new SpecialTreeVisitor(); 1262 JCClassDecl cdef = (JCClassDecl) tree; 1263 for (JCTree defs: cdef.defs) { 1264 defs.accept(sts); 1265 if (sts.specialized) return 0; 1266 } 1267 return FINAL; 1268 } 1269 1270/* ************************************************************************* 1271 * Type Validation 1272 **************************************************************************/ 1273 1274 /** Validate a type expression. That is, 1275 * check that all type arguments of a parametric type are within 1276 * their bounds. This must be done in a second phase after type attribution 1277 * since a class might have a subclass as type parameter bound. E.g: 1278 * 1279 * <pre>{@code 1280 * class B<A extends C> { ... } 1281 * class C extends B<C> { ... } 1282 * }</pre> 1283 * 1284 * and we can't make sure that the bound is already attributed because 1285 * of possible cycles. 1286 * 1287 * Visitor method: Validate a type expression, if it is not null, catching 1288 * and reporting any completion failures. 1289 */ 1290 void validate(JCTree tree, Env<AttrContext> env) { 1291 validate(tree, env, true); 1292 } 1293 void validate(JCTree tree, Env<AttrContext> env, boolean checkRaw) { 1294 new Validator(env).validateTree(tree, checkRaw, true); 1295 } 1296 1297 /** Visitor method: Validate a list of type expressions. 1298 */ 1299 void validate(List<? extends JCTree> trees, Env<AttrContext> env) { 1300 for (List<? extends JCTree> l = trees; l.nonEmpty(); l = l.tail) 1301 validate(l.head, env); 1302 } 1303 1304 /** A visitor class for type validation. 1305 */ 1306 class Validator extends JCTree.Visitor { 1307 1308 boolean checkRaw; 1309 boolean isOuter; 1310 Env<AttrContext> env; 1311 1312 Validator(Env<AttrContext> env) { 1313 this.env = env; 1314 } 1315 1316 @Override 1317 public void visitTypeArray(JCArrayTypeTree tree) { 1318 validateTree(tree.elemtype, checkRaw, isOuter); 1319 } 1320 1321 @Override 1322 public void visitTypeApply(JCTypeApply tree) { 1323 if (tree.type.hasTag(CLASS)) { 1324 List<JCExpression> args = tree.arguments; 1325 List<Type> forms = tree.type.tsym.type.getTypeArguments(); 1326 1327 Type incompatibleArg = firstIncompatibleTypeArg(tree.type); 1328 if (incompatibleArg != null) { 1329 for (JCTree arg : tree.arguments) { 1330 if (arg.type == incompatibleArg) { 1331 log.error(arg, "not.within.bounds", incompatibleArg, forms.head); 1332 } 1333 forms = forms.tail; 1334 } 1335 } 1336 1337 forms = tree.type.tsym.type.getTypeArguments(); 1338 1339 boolean is_java_lang_Class = tree.type.tsym.flatName() == names.java_lang_Class; 1340 1341 // For matching pairs of actual argument types `a' and 1342 // formal type parameters with declared bound `b' ... 1343 while (args.nonEmpty() && forms.nonEmpty()) { 1344 validateTree(args.head, 1345 !(isOuter && is_java_lang_Class), 1346 false); 1347 args = args.tail; 1348 forms = forms.tail; 1349 } 1350 1351 // Check that this type is either fully parameterized, or 1352 // not parameterized at all. 1353 if (tree.type.getEnclosingType().isRaw()) 1354 log.error(tree.pos(), "improperly.formed.type.inner.raw.param"); 1355 if (tree.clazz.hasTag(SELECT)) 1356 visitSelectInternal((JCFieldAccess)tree.clazz); 1357 } 1358 } 1359 1360 @Override 1361 public void visitTypeParameter(JCTypeParameter tree) { 1362 validateTrees(tree.bounds, true, isOuter); 1363 checkClassBounds(tree.pos(), tree.type); 1364 } 1365 1366 @Override 1367 public void visitWildcard(JCWildcard tree) { 1368 if (tree.inner != null) 1369 validateTree(tree.inner, true, isOuter); 1370 } 1371 1372 @Override 1373 public void visitSelect(JCFieldAccess tree) { 1374 if (tree.type.hasTag(CLASS)) { 1375 visitSelectInternal(tree); 1376 1377 // Check that this type is either fully parameterized, or 1378 // not parameterized at all. 1379 if (tree.selected.type.isParameterized() && tree.type.tsym.type.getTypeArguments().nonEmpty()) 1380 log.error(tree.pos(), "improperly.formed.type.param.missing"); 1381 } 1382 } 1383 1384 public void visitSelectInternal(JCFieldAccess tree) { 1385 if (tree.type.tsym.isStatic() && 1386 tree.selected.type.isParameterized()) { 1387 // The enclosing type is not a class, so we are 1388 // looking at a static member type. However, the 1389 // qualifying expression is parameterized. 1390 log.error(tree.pos(), "cant.select.static.class.from.param.type"); 1391 } else { 1392 // otherwise validate the rest of the expression 1393 tree.selected.accept(this); 1394 } 1395 } 1396 1397 @Override 1398 public void visitAnnotatedType(JCAnnotatedType tree) { 1399 tree.underlyingType.accept(this); 1400 } 1401 1402 @Override 1403 public void visitTypeIdent(JCPrimitiveTypeTree that) { 1404 if (that.type.hasTag(TypeTag.VOID)) { 1405 log.error(that.pos(), "void.not.allowed.here"); 1406 } 1407 super.visitTypeIdent(that); 1408 } 1409 1410 /** Default visitor method: do nothing. 1411 */ 1412 @Override 1413 public void visitTree(JCTree tree) { 1414 } 1415 1416 public void validateTree(JCTree tree, boolean checkRaw, boolean isOuter) { 1417 if (tree != null) { 1418 boolean prevCheckRaw = this.checkRaw; 1419 this.checkRaw = checkRaw; 1420 this.isOuter = isOuter; 1421 1422 try { 1423 tree.accept(this); 1424 if (checkRaw) 1425 checkRaw(tree, env); 1426 } catch (CompletionFailure ex) { 1427 completionError(tree.pos(), ex); 1428 } finally { 1429 this.checkRaw = prevCheckRaw; 1430 } 1431 } 1432 } 1433 1434 public void validateTrees(List<? extends JCTree> trees, boolean checkRaw, boolean isOuter) { 1435 for (List<? extends JCTree> l = trees; l.nonEmpty(); l = l.tail) 1436 validateTree(l.head, checkRaw, isOuter); 1437 } 1438 } 1439 1440 void checkRaw(JCTree tree, Env<AttrContext> env) { 1441 if (lint.isEnabled(LintCategory.RAW) && 1442 tree.type.hasTag(CLASS) && 1443 !TreeInfo.isDiamond(tree) && 1444 !withinAnonConstr(env) && 1445 tree.type.isRaw()) { 1446 log.warning(LintCategory.RAW, 1447 tree.pos(), "raw.class.use", tree.type, tree.type.tsym.type); 1448 } 1449 } 1450 //where 1451 private boolean withinAnonConstr(Env<AttrContext> env) { 1452 return env.enclClass.name.isEmpty() && 1453 env.enclMethod != null && env.enclMethod.name == names.init; 1454 } 1455 1456/* ************************************************************************* 1457 * Exception checking 1458 **************************************************************************/ 1459 1460 /* The following methods treat classes as sets that contain 1461 * the class itself and all their subclasses 1462 */ 1463 1464 /** Is given type a subtype of some of the types in given list? 1465 */ 1466 boolean subset(Type t, List<Type> ts) { 1467 for (List<Type> l = ts; l.nonEmpty(); l = l.tail) 1468 if (types.isSubtype(t, l.head)) return true; 1469 return false; 1470 } 1471 1472 /** Is given type a subtype or supertype of 1473 * some of the types in given list? 1474 */ 1475 boolean intersects(Type t, List<Type> ts) { 1476 for (List<Type> l = ts; l.nonEmpty(); l = l.tail) 1477 if (types.isSubtype(t, l.head) || types.isSubtype(l.head, t)) return true; 1478 return false; 1479 } 1480 1481 /** Add type set to given type list, unless it is a subclass of some class 1482 * in the list. 1483 */ 1484 List<Type> incl(Type t, List<Type> ts) { 1485 return subset(t, ts) ? ts : excl(t, ts).prepend(t); 1486 } 1487 1488 /** Remove type set from type set list. 1489 */ 1490 List<Type> excl(Type t, List<Type> ts) { 1491 if (ts.isEmpty()) { 1492 return ts; 1493 } else { 1494 List<Type> ts1 = excl(t, ts.tail); 1495 if (types.isSubtype(ts.head, t)) return ts1; 1496 else if (ts1 == ts.tail) return ts; 1497 else return ts1.prepend(ts.head); 1498 } 1499 } 1500 1501 /** Form the union of two type set lists. 1502 */ 1503 List<Type> union(List<Type> ts1, List<Type> ts2) { 1504 List<Type> ts = ts1; 1505 for (List<Type> l = ts2; l.nonEmpty(); l = l.tail) 1506 ts = incl(l.head, ts); 1507 return ts; 1508 } 1509 1510 /** Form the difference of two type lists. 1511 */ 1512 List<Type> diff(List<Type> ts1, List<Type> ts2) { 1513 List<Type> ts = ts1; 1514 for (List<Type> l = ts2; l.nonEmpty(); l = l.tail) 1515 ts = excl(l.head, ts); 1516 return ts; 1517 } 1518 1519 /** Form the intersection of two type lists. 1520 */ 1521 public List<Type> intersect(List<Type> ts1, List<Type> ts2) { 1522 List<Type> ts = List.nil(); 1523 for (List<Type> l = ts1; l.nonEmpty(); l = l.tail) 1524 if (subset(l.head, ts2)) ts = incl(l.head, ts); 1525 for (List<Type> l = ts2; l.nonEmpty(); l = l.tail) 1526 if (subset(l.head, ts1)) ts = incl(l.head, ts); 1527 return ts; 1528 } 1529 1530 /** Is exc an exception symbol that need not be declared? 1531 */ 1532 boolean isUnchecked(ClassSymbol exc) { 1533 return 1534 exc.kind == ERR || 1535 exc.isSubClass(syms.errorType.tsym, types) || 1536 exc.isSubClass(syms.runtimeExceptionType.tsym, types); 1537 } 1538 1539 /** Is exc an exception type that need not be declared? 1540 */ 1541 boolean isUnchecked(Type exc) { 1542 return 1543 (exc.hasTag(TYPEVAR)) ? isUnchecked(types.supertype(exc)) : 1544 (exc.hasTag(CLASS)) ? isUnchecked((ClassSymbol)exc.tsym) : 1545 exc.hasTag(BOT); 1546 } 1547 1548 /** Same, but handling completion failures. 1549 */ 1550 boolean isUnchecked(DiagnosticPosition pos, Type exc) { 1551 try { 1552 return isUnchecked(exc); 1553 } catch (CompletionFailure ex) { 1554 completionError(pos, ex); 1555 return true; 1556 } 1557 } 1558 1559 /** Is exc handled by given exception list? 1560 */ 1561 boolean isHandled(Type exc, List<Type> handled) { 1562 return isUnchecked(exc) || subset(exc, handled); 1563 } 1564 1565 /** Return all exceptions in thrown list that are not in handled list. 1566 * @param thrown The list of thrown exceptions. 1567 * @param handled The list of handled exceptions. 1568 */ 1569 List<Type> unhandled(List<Type> thrown, List<Type> handled) { 1570 List<Type> unhandled = List.nil(); 1571 for (List<Type> l = thrown; l.nonEmpty(); l = l.tail) 1572 if (!isHandled(l.head, handled)) unhandled = unhandled.prepend(l.head); 1573 return unhandled; 1574 } 1575 1576/* ************************************************************************* 1577 * Overriding/Implementation checking 1578 **************************************************************************/ 1579 1580 /** The level of access protection given by a flag set, 1581 * where PRIVATE is highest and PUBLIC is lowest. 1582 */ 1583 static int protection(long flags) { 1584 switch ((short)(flags & AccessFlags)) { 1585 case PRIVATE: return 3; 1586 case PROTECTED: return 1; 1587 default: 1588 case PUBLIC: return 0; 1589 case 0: return 2; 1590 } 1591 } 1592 1593 /** A customized "cannot override" error message. 1594 * @param m The overriding method. 1595 * @param other The overridden method. 1596 * @return An internationalized string. 1597 */ 1598 Object cannotOverride(MethodSymbol m, MethodSymbol other) { 1599 String key; 1600 if ((other.owner.flags() & INTERFACE) == 0) 1601 key = "cant.override"; 1602 else if ((m.owner.flags() & INTERFACE) == 0) 1603 key = "cant.implement"; 1604 else 1605 key = "clashes.with"; 1606 return diags.fragment(key, m, m.location(), other, other.location()); 1607 } 1608 1609 /** A customized "override" warning message. 1610 * @param m The overriding method. 1611 * @param other The overridden method. 1612 * @return An internationalized string. 1613 */ 1614 Object uncheckedOverrides(MethodSymbol m, MethodSymbol other) { 1615 String key; 1616 if ((other.owner.flags() & INTERFACE) == 0) 1617 key = "unchecked.override"; 1618 else if ((m.owner.flags() & INTERFACE) == 0) 1619 key = "unchecked.implement"; 1620 else 1621 key = "unchecked.clash.with"; 1622 return diags.fragment(key, m, m.location(), other, other.location()); 1623 } 1624 1625 /** A customized "override" warning message. 1626 * @param m The overriding method. 1627 * @param other The overridden method. 1628 * @return An internationalized string. 1629 */ 1630 Object varargsOverrides(MethodSymbol m, MethodSymbol other) { 1631 String key; 1632 if ((other.owner.flags() & INTERFACE) == 0) 1633 key = "varargs.override"; 1634 else if ((m.owner.flags() & INTERFACE) == 0) 1635 key = "varargs.implement"; 1636 else 1637 key = "varargs.clash.with"; 1638 return diags.fragment(key, m, m.location(), other, other.location()); 1639 } 1640 1641 /** Check that this method conforms with overridden method 'other'. 1642 * where `origin' is the class where checking started. 1643 * Complications: 1644 * (1) Do not check overriding of synthetic methods 1645 * (reason: they might be final). 1646 * todo: check whether this is still necessary. 1647 * (2) Admit the case where an interface proxy throws fewer exceptions 1648 * than the method it implements. Augment the proxy methods with the 1649 * undeclared exceptions in this case. 1650 * (3) When generics are enabled, admit the case where an interface proxy 1651 * has a result type 1652 * extended by the result type of the method it implements. 1653 * Change the proxies result type to the smaller type in this case. 1654 * 1655 * @param tree The tree from which positions 1656 * are extracted for errors. 1657 * @param m The overriding method. 1658 * @param other The overridden method. 1659 * @param origin The class of which the overriding method 1660 * is a member. 1661 */ 1662 void checkOverride(JCTree tree, 1663 MethodSymbol m, 1664 MethodSymbol other, 1665 ClassSymbol origin) { 1666 // Don't check overriding of synthetic methods or by bridge methods. 1667 if ((m.flags() & (SYNTHETIC|BRIDGE)) != 0 || (other.flags() & SYNTHETIC) != 0) { 1668 return; 1669 } 1670 1671 // Error if static method overrides instance method (JLS 8.4.6.2). 1672 if ((m.flags() & STATIC) != 0 && 1673 (other.flags() & STATIC) == 0) { 1674 log.error(TreeInfo.diagnosticPositionFor(m, tree), "override.static", 1675 cannotOverride(m, other)); 1676 m.flags_field |= BAD_OVERRIDE; 1677 return; 1678 } 1679 1680 // Error if instance method overrides static or final 1681 // method (JLS 8.4.6.1). 1682 if ((other.flags() & FINAL) != 0 || 1683 (m.flags() & STATIC) == 0 && 1684 (other.flags() & STATIC) != 0) { 1685 log.error(TreeInfo.diagnosticPositionFor(m, tree), "override.meth", 1686 cannotOverride(m, other), 1687 asFlagSet(other.flags() & (FINAL | STATIC))); 1688 m.flags_field |= BAD_OVERRIDE; 1689 return; 1690 } 1691 1692 if ((m.owner.flags() & ANNOTATION) != 0) { 1693 // handled in validateAnnotationMethod 1694 return; 1695 } 1696 1697 // Error if overriding method has weaker access (JLS 8.4.6.3). 1698 if (protection(m.flags()) > protection(other.flags())) { 1699 log.error(TreeInfo.diagnosticPositionFor(m, tree), "override.weaker.access", 1700 cannotOverride(m, other), 1701 (other.flags() & AccessFlags) == 0 ? 1702 "package" : 1703 asFlagSet(other.flags() & AccessFlags)); 1704 m.flags_field |= BAD_OVERRIDE; 1705 return; 1706 } 1707 1708 Type mt = types.memberType(origin.type, m); 1709 Type ot = types.memberType(origin.type, other); 1710 // Error if overriding result type is different 1711 // (or, in the case of generics mode, not a subtype) of 1712 // overridden result type. We have to rename any type parameters 1713 // before comparing types. 1714 List<Type> mtvars = mt.getTypeArguments(); 1715 List<Type> otvars = ot.getTypeArguments(); 1716 Type mtres = mt.getReturnType(); 1717 Type otres = types.subst(ot.getReturnType(), otvars, mtvars); 1718 1719 overrideWarner.clear(); 1720 boolean resultTypesOK = 1721 types.returnTypeSubstitutable(mt, ot, otres, overrideWarner); 1722 if (!resultTypesOK) { 1723 if ((m.flags() & STATIC) != 0 && (other.flags() & STATIC) != 0) { 1724 log.error(TreeInfo.diagnosticPositionFor(m, tree), 1725 Errors.OverrideIncompatibleRet(Fragments.CantHide(m, m.location(), other, 1726 other.location()), mtres, otres)); 1727 m.flags_field |= BAD_OVERRIDE; 1728 } else { 1729 log.error(TreeInfo.diagnosticPositionFor(m, tree), 1730 "override.incompatible.ret", 1731 cannotOverride(m, other), 1732 mtres, otres); 1733 m.flags_field |= BAD_OVERRIDE; 1734 } 1735 return; 1736 } else if (overrideWarner.hasNonSilentLint(LintCategory.UNCHECKED)) { 1737 warnUnchecked(TreeInfo.diagnosticPositionFor(m, tree), 1738 "override.unchecked.ret", 1739 uncheckedOverrides(m, other), 1740 mtres, otres); 1741 } 1742 1743 // Error if overriding method throws an exception not reported 1744 // by overridden method. 1745 List<Type> otthrown = types.subst(ot.getThrownTypes(), otvars, mtvars); 1746 List<Type> unhandledErased = unhandled(mt.getThrownTypes(), types.erasure(otthrown)); 1747 List<Type> unhandledUnerased = unhandled(mt.getThrownTypes(), otthrown); 1748 if (unhandledErased.nonEmpty()) { 1749 log.error(TreeInfo.diagnosticPositionFor(m, tree), 1750 "override.meth.doesnt.throw", 1751 cannotOverride(m, other), 1752 unhandledUnerased.head); 1753 m.flags_field |= BAD_OVERRIDE; 1754 return; 1755 } 1756 else if (unhandledUnerased.nonEmpty()) { 1757 warnUnchecked(TreeInfo.diagnosticPositionFor(m, tree), 1758 "override.unchecked.thrown", 1759 cannotOverride(m, other), 1760 unhandledUnerased.head); 1761 return; 1762 } 1763 1764 // Optional warning if varargs don't agree 1765 if ((((m.flags() ^ other.flags()) & Flags.VARARGS) != 0) 1766 && lint.isEnabled(LintCategory.OVERRIDES)) { 1767 log.warning(TreeInfo.diagnosticPositionFor(m, tree), 1768 ((m.flags() & Flags.VARARGS) != 0) 1769 ? "override.varargs.missing" 1770 : "override.varargs.extra", 1771 varargsOverrides(m, other)); 1772 } 1773 1774 // Warn if instance method overrides bridge method (compiler spec ??) 1775 if ((other.flags() & BRIDGE) != 0) { 1776 log.warning(TreeInfo.diagnosticPositionFor(m, tree), "override.bridge", 1777 uncheckedOverrides(m, other)); 1778 } 1779 1780 // Warn if a deprecated method overridden by a non-deprecated one. 1781 if (!isDeprecatedOverrideIgnorable(other, origin)) { 1782 Lint prevLint = setLint(lint.augment(m)); 1783 try { 1784 checkDeprecated(TreeInfo.diagnosticPositionFor(m, tree), m, other); 1785 } finally { 1786 setLint(prevLint); 1787 } 1788 } 1789 } 1790 // where 1791 private boolean isDeprecatedOverrideIgnorable(MethodSymbol m, ClassSymbol origin) { 1792 // If the method, m, is defined in an interface, then ignore the issue if the method 1793 // is only inherited via a supertype and also implemented in the supertype, 1794 // because in that case, we will rediscover the issue when examining the method 1795 // in the supertype. 1796 // If the method, m, is not defined in an interface, then the only time we need to 1797 // address the issue is when the method is the supertype implemementation: any other 1798 // case, we will have dealt with when examining the supertype classes 1799 ClassSymbol mc = m.enclClass(); 1800 Type st = types.supertype(origin.type); 1801 if (!st.hasTag(CLASS)) 1802 return true; 1803 MethodSymbol stimpl = m.implementation((ClassSymbol)st.tsym, types, false); 1804 1805 if (mc != null && ((mc.flags() & INTERFACE) != 0)) { 1806 List<Type> intfs = types.interfaces(origin.type); 1807 return (intfs.contains(mc.type) ? false : (stimpl != null)); 1808 } 1809 else 1810 return (stimpl != m); 1811 } 1812 1813 1814 // used to check if there were any unchecked conversions 1815 Warner overrideWarner = new Warner(); 1816 1817 /** Check that a class does not inherit two concrete methods 1818 * with the same signature. 1819 * @param pos Position to be used for error reporting. 1820 * @param site The class type to be checked. 1821 */ 1822 public void checkCompatibleConcretes(DiagnosticPosition pos, Type site) { 1823 Type sup = types.supertype(site); 1824 if (!sup.hasTag(CLASS)) return; 1825 1826 for (Type t1 = sup; 1827 t1.hasTag(CLASS) && t1.tsym.type.isParameterized(); 1828 t1 = types.supertype(t1)) { 1829 for (Symbol s1 : t1.tsym.members().getSymbols(NON_RECURSIVE)) { 1830 if (s1.kind != MTH || 1831 (s1.flags() & (STATIC|SYNTHETIC|BRIDGE)) != 0 || 1832 !s1.isInheritedIn(site.tsym, types) || 1833 ((MethodSymbol)s1).implementation(site.tsym, 1834 types, 1835 true) != s1) 1836 continue; 1837 Type st1 = types.memberType(t1, s1); 1838 int s1ArgsLength = st1.getParameterTypes().length(); 1839 if (st1 == s1.type) continue; 1840 1841 for (Type t2 = sup; 1842 t2.hasTag(CLASS); 1843 t2 = types.supertype(t2)) { 1844 for (Symbol s2 : t2.tsym.members().getSymbolsByName(s1.name)) { 1845 if (s2 == s1 || 1846 s2.kind != MTH || 1847 (s2.flags() & (STATIC|SYNTHETIC|BRIDGE)) != 0 || 1848 s2.type.getParameterTypes().length() != s1ArgsLength || 1849 !s2.isInheritedIn(site.tsym, types) || 1850 ((MethodSymbol)s2).implementation(site.tsym, 1851 types, 1852 true) != s2) 1853 continue; 1854 Type st2 = types.memberType(t2, s2); 1855 if (types.overrideEquivalent(st1, st2)) 1856 log.error(pos, "concrete.inheritance.conflict", 1857 s1, t1, s2, t2, sup); 1858 } 1859 } 1860 } 1861 } 1862 } 1863 1864 /** Check that classes (or interfaces) do not each define an abstract 1865 * method with same name and arguments but incompatible return types. 1866 * @param pos Position to be used for error reporting. 1867 * @param t1 The first argument type. 1868 * @param t2 The second argument type. 1869 */ 1870 public boolean checkCompatibleAbstracts(DiagnosticPosition pos, 1871 Type t1, 1872 Type t2, 1873 Type site) { 1874 if ((site.tsym.flags() & COMPOUND) != 0) { 1875 // special case for intersections: need to eliminate wildcards in supertypes 1876 t1 = types.capture(t1); 1877 t2 = types.capture(t2); 1878 } 1879 return firstIncompatibility(pos, t1, t2, site) == null; 1880 } 1881 1882 /** Return the first method which is defined with same args 1883 * but different return types in two given interfaces, or null if none 1884 * exists. 1885 * @param t1 The first type. 1886 * @param t2 The second type. 1887 * @param site The most derived type. 1888 * @returns symbol from t2 that conflicts with one in t1. 1889 */ 1890 private Symbol firstIncompatibility(DiagnosticPosition pos, Type t1, Type t2, Type site) { 1891 Map<TypeSymbol,Type> interfaces1 = new HashMap<>(); 1892 closure(t1, interfaces1); 1893 Map<TypeSymbol,Type> interfaces2; 1894 if (t1 == t2) 1895 interfaces2 = interfaces1; 1896 else 1897 closure(t2, interfaces1, interfaces2 = new HashMap<>()); 1898 1899 for (Type t3 : interfaces1.values()) { 1900 for (Type t4 : interfaces2.values()) { 1901 Symbol s = firstDirectIncompatibility(pos, t3, t4, site); 1902 if (s != null) return s; 1903 } 1904 } 1905 return null; 1906 } 1907 1908 /** Compute all the supertypes of t, indexed by type symbol. */ 1909 private void closure(Type t, Map<TypeSymbol,Type> typeMap) { 1910 if (!t.hasTag(CLASS)) return; 1911 if (typeMap.put(t.tsym, t) == null) { 1912 closure(types.supertype(t), typeMap); 1913 for (Type i : types.interfaces(t)) 1914 closure(i, typeMap); 1915 } 1916 } 1917 1918 /** Compute all the supertypes of t, indexed by type symbol (except thise in typesSkip). */ 1919 private void closure(Type t, Map<TypeSymbol,Type> typesSkip, Map<TypeSymbol,Type> typeMap) { 1920 if (!t.hasTag(CLASS)) return; 1921 if (typesSkip.get(t.tsym) != null) return; 1922 if (typeMap.put(t.tsym, t) == null) { 1923 closure(types.supertype(t), typesSkip, typeMap); 1924 for (Type i : types.interfaces(t)) 1925 closure(i, typesSkip, typeMap); 1926 } 1927 } 1928 1929 /** Return the first method in t2 that conflicts with a method from t1. */ 1930 private Symbol firstDirectIncompatibility(DiagnosticPosition pos, Type t1, Type t2, Type site) { 1931 for (Symbol s1 : t1.tsym.members().getSymbols(NON_RECURSIVE)) { 1932 Type st1 = null; 1933 if (s1.kind != MTH || !s1.isInheritedIn(site.tsym, types) || 1934 (s1.flags() & SYNTHETIC) != 0) continue; 1935 Symbol impl = ((MethodSymbol)s1).implementation(site.tsym, types, false); 1936 if (impl != null && (impl.flags() & ABSTRACT) == 0) continue; 1937 for (Symbol s2 : t2.tsym.members().getSymbolsByName(s1.name)) { 1938 if (s1 == s2) continue; 1939 if (s2.kind != MTH || !s2.isInheritedIn(site.tsym, types) || 1940 (s2.flags() & SYNTHETIC) != 0) continue; 1941 if (st1 == null) st1 = types.memberType(t1, s1); 1942 Type st2 = types.memberType(t2, s2); 1943 if (types.overrideEquivalent(st1, st2)) { 1944 List<Type> tvars1 = st1.getTypeArguments(); 1945 List<Type> tvars2 = st2.getTypeArguments(); 1946 Type rt1 = st1.getReturnType(); 1947 Type rt2 = types.subst(st2.getReturnType(), tvars2, tvars1); 1948 boolean compat = 1949 types.isSameType(rt1, rt2) || 1950 !rt1.isPrimitiveOrVoid() && 1951 !rt2.isPrimitiveOrVoid() && 1952 (types.covariantReturnType(rt1, rt2, types.noWarnings) || 1953 types.covariantReturnType(rt2, rt1, types.noWarnings)) || 1954 checkCommonOverriderIn(s1,s2,site); 1955 if (!compat) { 1956 log.error(pos, "types.incompatible.diff.ret", 1957 t1, t2, s2.name + 1958 "(" + types.memberType(t2, s2).getParameterTypes() + ")"); 1959 return s2; 1960 } 1961 } else if (checkNameClash((ClassSymbol)site.tsym, s1, s2) && 1962 !checkCommonOverriderIn(s1, s2, site)) { 1963 log.error(pos, 1964 "name.clash.same.erasure.no.override", 1965 s1, s1.location(), 1966 s2, s2.location()); 1967 return s2; 1968 } 1969 } 1970 } 1971 return null; 1972 } 1973 //WHERE 1974 boolean checkCommonOverriderIn(Symbol s1, Symbol s2, Type site) { 1975 Map<TypeSymbol,Type> supertypes = new HashMap<>(); 1976 Type st1 = types.memberType(site, s1); 1977 Type st2 = types.memberType(site, s2); 1978 closure(site, supertypes); 1979 for (Type t : supertypes.values()) { 1980 for (Symbol s3 : t.tsym.members().getSymbolsByName(s1.name)) { 1981 if (s3 == s1 || s3 == s2 || s3.kind != MTH || (s3.flags() & (BRIDGE|SYNTHETIC)) != 0) continue; 1982 Type st3 = types.memberType(site,s3); 1983 if (types.overrideEquivalent(st3, st1) && 1984 types.overrideEquivalent(st3, st2) && 1985 types.returnTypeSubstitutable(st3, st1) && 1986 types.returnTypeSubstitutable(st3, st2)) { 1987 return true; 1988 } 1989 } 1990 } 1991 return false; 1992 } 1993 1994 /** Check that a given method conforms with any method it overrides. 1995 * @param tree The tree from which positions are extracted 1996 * for errors. 1997 * @param m The overriding method. 1998 */ 1999 void checkOverride(Env<AttrContext> env, JCMethodDecl tree, MethodSymbol m) { 2000 ClassSymbol origin = (ClassSymbol)m.owner; 2001 if ((origin.flags() & ENUM) != 0 && names.finalize.equals(m.name)) 2002 if (m.overrides(syms.enumFinalFinalize, origin, types, false)) { 2003 log.error(tree.pos(), "enum.no.finalize"); 2004 return; 2005 } 2006 for (Type t = origin.type; t.hasTag(CLASS); 2007 t = types.supertype(t)) { 2008 if (t != origin.type) { 2009 checkOverride(tree, t, origin, m); 2010 } 2011 for (Type t2 : types.interfaces(t)) { 2012 checkOverride(tree, t2, origin, m); 2013 } 2014 } 2015 2016 final boolean explicitOverride = m.attribute(syms.overrideType.tsym) != null; 2017 // Check if this method must override a super method due to being annotated with @Override 2018 // or by virtue of being a member of a diamond inferred anonymous class. Latter case is to 2019 // be treated "as if as they were annotated" with @Override. 2020 boolean mustOverride = explicitOverride || 2021 (env.info.isAnonymousDiamond && !m.isConstructor() && !m.isPrivate()); 2022 if (mustOverride && !isOverrider(m)) { 2023 DiagnosticPosition pos = tree.pos(); 2024 for (JCAnnotation a : tree.getModifiers().annotations) { 2025 if (a.annotationType.type.tsym == syms.overrideType.tsym) { 2026 pos = a.pos(); 2027 break; 2028 } 2029 } 2030 log.error(pos, 2031 explicitOverride ? Errors.MethodDoesNotOverrideSuperclass : 2032 Errors.AnonymousDiamondMethodDoesNotOverrideSuperclass(Fragments.DiamondAnonymousMethodsImplicitlyOverride)); 2033 } 2034 } 2035 2036 void checkOverride(JCTree tree, Type site, ClassSymbol origin, MethodSymbol m) { 2037 TypeSymbol c = site.tsym; 2038 for (Symbol sym : c.members().getSymbolsByName(m.name)) { 2039 if (m.overrides(sym, origin, types, false)) { 2040 if ((sym.flags() & ABSTRACT) == 0) { 2041 checkOverride(tree, m, (MethodSymbol)sym, origin); 2042 } 2043 } 2044 } 2045 } 2046 2047 private Filter<Symbol> equalsHasCodeFilter = new Filter<Symbol>() { 2048 public boolean accepts(Symbol s) { 2049 return MethodSymbol.implementation_filter.accepts(s) && 2050 (s.flags() & BAD_OVERRIDE) == 0; 2051 2052 } 2053 }; 2054 2055 public void checkClassOverrideEqualsAndHashIfNeeded(DiagnosticPosition pos, 2056 ClassSymbol someClass) { 2057 /* At present, annotations cannot possibly have a method that is override 2058 * equivalent with Object.equals(Object) but in any case the condition is 2059 * fine for completeness. 2060 */ 2061 if (someClass == (ClassSymbol)syms.objectType.tsym || 2062 someClass.isInterface() || someClass.isEnum() || 2063 (someClass.flags() & ANNOTATION) != 0 || 2064 (someClass.flags() & ABSTRACT) != 0) return; 2065 //anonymous inner classes implementing interfaces need especial treatment 2066 if (someClass.isAnonymous()) { 2067 List<Type> interfaces = types.interfaces(someClass.type); 2068 if (interfaces != null && !interfaces.isEmpty() && 2069 interfaces.head.tsym == syms.comparatorType.tsym) return; 2070 } 2071 checkClassOverrideEqualsAndHash(pos, someClass); 2072 } 2073 2074 private void checkClassOverrideEqualsAndHash(DiagnosticPosition pos, 2075 ClassSymbol someClass) { 2076 if (lint.isEnabled(LintCategory.OVERRIDES)) { 2077 MethodSymbol equalsAtObject = (MethodSymbol)syms.objectType 2078 .tsym.members().findFirst(names.equals); 2079 MethodSymbol hashCodeAtObject = (MethodSymbol)syms.objectType 2080 .tsym.members().findFirst(names.hashCode); 2081 boolean overridesEquals = types.implementation(equalsAtObject, 2082 someClass, false, equalsHasCodeFilter).owner == someClass; 2083 boolean overridesHashCode = types.implementation(hashCodeAtObject, 2084 someClass, false, equalsHasCodeFilter) != hashCodeAtObject; 2085 2086 if (overridesEquals && !overridesHashCode) { 2087 log.warning(LintCategory.OVERRIDES, pos, 2088 "override.equals.but.not.hashcode", someClass); 2089 } 2090 } 2091 } 2092 2093 private boolean checkNameClash(ClassSymbol origin, Symbol s1, Symbol s2) { 2094 ClashFilter cf = new ClashFilter(origin.type); 2095 return (cf.accepts(s1) && 2096 cf.accepts(s2) && 2097 types.hasSameArgs(s1.erasure(types), s2.erasure(types))); 2098 } 2099 2100 2101 /** Check that all abstract members of given class have definitions. 2102 * @param pos Position to be used for error reporting. 2103 * @param c The class. 2104 */ 2105 void checkAllDefined(DiagnosticPosition pos, ClassSymbol c) { 2106 MethodSymbol undef = types.firstUnimplementedAbstract(c); 2107 if (undef != null) { 2108 MethodSymbol undef1 = 2109 new MethodSymbol(undef.flags(), undef.name, 2110 types.memberType(c.type, undef), undef.owner); 2111 log.error(pos, "does.not.override.abstract", 2112 c, undef1, undef1.location()); 2113 } 2114 } 2115 2116 void checkNonCyclicDecl(JCClassDecl tree) { 2117 CycleChecker cc = new CycleChecker(); 2118 cc.scan(tree); 2119 if (!cc.errorFound && !cc.partialCheck) { 2120 tree.sym.flags_field |= ACYCLIC; 2121 } 2122 } 2123 2124 class CycleChecker extends TreeScanner { 2125 2126 List<Symbol> seenClasses = List.nil(); 2127 boolean errorFound = false; 2128 boolean partialCheck = false; 2129 2130 private void checkSymbol(DiagnosticPosition pos, Symbol sym) { 2131 if (sym != null && sym.kind == TYP) { 2132 Env<AttrContext> classEnv = enter.getEnv((TypeSymbol)sym); 2133 if (classEnv != null) { 2134 DiagnosticSource prevSource = log.currentSource(); 2135 try { 2136 log.useSource(classEnv.toplevel.sourcefile); 2137 scan(classEnv.tree); 2138 } 2139 finally { 2140 log.useSource(prevSource.getFile()); 2141 } 2142 } else if (sym.kind == TYP) { 2143 checkClass(pos, sym, List.<JCTree>nil()); 2144 } 2145 } else { 2146 //not completed yet 2147 partialCheck = true; 2148 } 2149 } 2150 2151 @Override 2152 public void visitSelect(JCFieldAccess tree) { 2153 super.visitSelect(tree); 2154 checkSymbol(tree.pos(), tree.sym); 2155 } 2156 2157 @Override 2158 public void visitIdent(JCIdent tree) { 2159 checkSymbol(tree.pos(), tree.sym); 2160 } 2161 2162 @Override 2163 public void visitTypeApply(JCTypeApply tree) { 2164 scan(tree.clazz); 2165 } 2166 2167 @Override 2168 public void visitTypeArray(JCArrayTypeTree tree) { 2169 scan(tree.elemtype); 2170 } 2171 2172 @Override 2173 public void visitClassDef(JCClassDecl tree) { 2174 List<JCTree> supertypes = List.nil(); 2175 if (tree.getExtendsClause() != null) { 2176 supertypes = supertypes.prepend(tree.getExtendsClause()); 2177 } 2178 if (tree.getImplementsClause() != null) { 2179 for (JCTree intf : tree.getImplementsClause()) { 2180 supertypes = supertypes.prepend(intf); 2181 } 2182 } 2183 checkClass(tree.pos(), tree.sym, supertypes); 2184 } 2185 2186 void checkClass(DiagnosticPosition pos, Symbol c, List<JCTree> supertypes) { 2187 if ((c.flags_field & ACYCLIC) != 0) 2188 return; 2189 if (seenClasses.contains(c)) { 2190 errorFound = true; 2191 noteCyclic(pos, (ClassSymbol)c); 2192 } else if (!c.type.isErroneous()) { 2193 try { 2194 seenClasses = seenClasses.prepend(c); 2195 if (c.type.hasTag(CLASS)) { 2196 if (supertypes.nonEmpty()) { 2197 scan(supertypes); 2198 } 2199 else { 2200 ClassType ct = (ClassType)c.type; 2201 if (ct.supertype_field == null || 2202 ct.interfaces_field == null) { 2203 //not completed yet 2204 partialCheck = true; 2205 return; 2206 } 2207 checkSymbol(pos, ct.supertype_field.tsym); 2208 for (Type intf : ct.interfaces_field) { 2209 checkSymbol(pos, intf.tsym); 2210 } 2211 } 2212 if (c.owner.kind == TYP) { 2213 checkSymbol(pos, c.owner); 2214 } 2215 } 2216 } finally { 2217 seenClasses = seenClasses.tail; 2218 } 2219 } 2220 } 2221 } 2222 2223 /** Check for cyclic references. Issue an error if the 2224 * symbol of the type referred to has a LOCKED flag set. 2225 * 2226 * @param pos Position to be used for error reporting. 2227 * @param t The type referred to. 2228 */ 2229 void checkNonCyclic(DiagnosticPosition pos, Type t) { 2230 checkNonCyclicInternal(pos, t); 2231 } 2232 2233 2234 void checkNonCyclic(DiagnosticPosition pos, TypeVar t) { 2235 checkNonCyclic1(pos, t, List.<TypeVar>nil()); 2236 } 2237 2238 private void checkNonCyclic1(DiagnosticPosition pos, Type t, List<TypeVar> seen) { 2239 final TypeVar tv; 2240 if (t.hasTag(TYPEVAR) && (t.tsym.flags() & UNATTRIBUTED) != 0) 2241 return; 2242 if (seen.contains(t)) { 2243 tv = (TypeVar)t; 2244 tv.bound = types.createErrorType(t); 2245 log.error(pos, "cyclic.inheritance", t); 2246 } else if (t.hasTag(TYPEVAR)) { 2247 tv = (TypeVar)t; 2248 seen = seen.prepend(tv); 2249 for (Type b : types.getBounds(tv)) 2250 checkNonCyclic1(pos, b, seen); 2251 } 2252 } 2253 2254 /** Check for cyclic references. Issue an error if the 2255 * symbol of the type referred to has a LOCKED flag set. 2256 * 2257 * @param pos Position to be used for error reporting. 2258 * @param t The type referred to. 2259 * @returns True if the check completed on all attributed classes 2260 */ 2261 private boolean checkNonCyclicInternal(DiagnosticPosition pos, Type t) { 2262 boolean complete = true; // was the check complete? 2263 //- System.err.println("checkNonCyclicInternal("+t+");");//DEBUG 2264 Symbol c = t.tsym; 2265 if ((c.flags_field & ACYCLIC) != 0) return true; 2266 2267 if ((c.flags_field & LOCKED) != 0) { 2268 noteCyclic(pos, (ClassSymbol)c); 2269 } else if (!c.type.isErroneous()) { 2270 try { 2271 c.flags_field |= LOCKED; 2272 if (c.type.hasTag(CLASS)) { 2273 ClassType clazz = (ClassType)c.type; 2274 if (clazz.interfaces_field != null) 2275 for (List<Type> l=clazz.interfaces_field; l.nonEmpty(); l=l.tail) 2276 complete &= checkNonCyclicInternal(pos, l.head); 2277 if (clazz.supertype_field != null) { 2278 Type st = clazz.supertype_field; 2279 if (st != null && st.hasTag(CLASS)) 2280 complete &= checkNonCyclicInternal(pos, st); 2281 } 2282 if (c.owner.kind == TYP) 2283 complete &= checkNonCyclicInternal(pos, c.owner.type); 2284 } 2285 } finally { 2286 c.flags_field &= ~LOCKED; 2287 } 2288 } 2289 if (complete) 2290 complete = ((c.flags_field & UNATTRIBUTED) == 0) && c.isCompleted(); 2291 if (complete) c.flags_field |= ACYCLIC; 2292 return complete; 2293 } 2294 2295 /** Note that we found an inheritance cycle. */ 2296 private void noteCyclic(DiagnosticPosition pos, ClassSymbol c) { 2297 log.error(pos, "cyclic.inheritance", c); 2298 for (List<Type> l=types.interfaces(c.type); l.nonEmpty(); l=l.tail) 2299 l.head = types.createErrorType((ClassSymbol)l.head.tsym, Type.noType); 2300 Type st = types.supertype(c.type); 2301 if (st.hasTag(CLASS)) 2302 ((ClassType)c.type).supertype_field = types.createErrorType((ClassSymbol)st.tsym, Type.noType); 2303 c.type = types.createErrorType(c, c.type); 2304 c.flags_field |= ACYCLIC; 2305 } 2306 2307 /** Check that all methods which implement some 2308 * method conform to the method they implement. 2309 * @param tree The class definition whose members are checked. 2310 */ 2311 void checkImplementations(JCClassDecl tree) { 2312 checkImplementations(tree, tree.sym, tree.sym); 2313 } 2314 //where 2315 /** Check that all methods which implement some 2316 * method in `ic' conform to the method they implement. 2317 */ 2318 void checkImplementations(JCTree tree, ClassSymbol origin, ClassSymbol ic) { 2319 for (List<Type> l = types.closure(ic.type); l.nonEmpty(); l = l.tail) { 2320 ClassSymbol lc = (ClassSymbol)l.head.tsym; 2321 if ((lc.flags() & ABSTRACT) != 0) { 2322 for (Symbol sym : lc.members().getSymbols(NON_RECURSIVE)) { 2323 if (sym.kind == MTH && 2324 (sym.flags() & (STATIC|ABSTRACT)) == ABSTRACT) { 2325 MethodSymbol absmeth = (MethodSymbol)sym; 2326 MethodSymbol implmeth = absmeth.implementation(origin, types, false); 2327 if (implmeth != null && implmeth != absmeth && 2328 (implmeth.owner.flags() & INTERFACE) == 2329 (origin.flags() & INTERFACE)) { 2330 // don't check if implmeth is in a class, yet 2331 // origin is an interface. This case arises only 2332 // if implmeth is declared in Object. The reason is 2333 // that interfaces really don't inherit from 2334 // Object it's just that the compiler represents 2335 // things that way. 2336 checkOverride(tree, implmeth, absmeth, origin); 2337 } 2338 } 2339 } 2340 } 2341 } 2342 } 2343 2344 /** Check that all abstract methods implemented by a class are 2345 * mutually compatible. 2346 * @param pos Position to be used for error reporting. 2347 * @param c The class whose interfaces are checked. 2348 */ 2349 void checkCompatibleSupertypes(DiagnosticPosition pos, Type c) { 2350 List<Type> supertypes = types.interfaces(c); 2351 Type supertype = types.supertype(c); 2352 if (supertype.hasTag(CLASS) && 2353 (supertype.tsym.flags() & ABSTRACT) != 0) 2354 supertypes = supertypes.prepend(supertype); 2355 for (List<Type> l = supertypes; l.nonEmpty(); l = l.tail) { 2356 if (!l.head.getTypeArguments().isEmpty() && 2357 !checkCompatibleAbstracts(pos, l.head, l.head, c)) 2358 return; 2359 for (List<Type> m = supertypes; m != l; m = m.tail) 2360 if (!checkCompatibleAbstracts(pos, l.head, m.head, c)) 2361 return; 2362 } 2363 checkCompatibleConcretes(pos, c); 2364 } 2365 2366 void checkConflicts(DiagnosticPosition pos, Symbol sym, TypeSymbol c) { 2367 for (Type ct = c.type; ct != Type.noType ; ct = types.supertype(ct)) { 2368 for (Symbol sym2 : ct.tsym.members().getSymbolsByName(sym.name, NON_RECURSIVE)) { 2369 // VM allows methods and variables with differing types 2370 if (sym.kind == sym2.kind && 2371 types.isSameType(types.erasure(sym.type), types.erasure(sym2.type)) && 2372 sym != sym2 && 2373 (sym.flags() & Flags.SYNTHETIC) != (sym2.flags() & Flags.SYNTHETIC) && 2374 (sym.flags() & BRIDGE) == 0 && (sym2.flags() & BRIDGE) == 0) { 2375 syntheticError(pos, (sym2.flags() & SYNTHETIC) == 0 ? sym2 : sym); 2376 return; 2377 } 2378 } 2379 } 2380 } 2381 2382 /** Check that all non-override equivalent methods accessible from 'site' 2383 * are mutually compatible (JLS 8.4.8/9.4.1). 2384 * 2385 * @param pos Position to be used for error reporting. 2386 * @param site The class whose methods are checked. 2387 * @param sym The method symbol to be checked. 2388 */ 2389 void checkOverrideClashes(DiagnosticPosition pos, Type site, MethodSymbol sym) { 2390 ClashFilter cf = new ClashFilter(site); 2391 //for each method m1 that is overridden (directly or indirectly) 2392 //by method 'sym' in 'site'... 2393 2394 List<MethodSymbol> potentiallyAmbiguousList = List.nil(); 2395 boolean overridesAny = false; 2396 for (Symbol m1 : types.membersClosure(site, false).getSymbolsByName(sym.name, cf)) { 2397 if (!sym.overrides(m1, site.tsym, types, false)) { 2398 if (m1 == sym) { 2399 continue; 2400 } 2401 2402 if (!overridesAny) { 2403 potentiallyAmbiguousList = potentiallyAmbiguousList.prepend((MethodSymbol)m1); 2404 } 2405 continue; 2406 } 2407 2408 if (m1 != sym) { 2409 overridesAny = true; 2410 potentiallyAmbiguousList = List.nil(); 2411 } 2412 2413 //...check each method m2 that is a member of 'site' 2414 for (Symbol m2 : types.membersClosure(site, false).getSymbolsByName(sym.name, cf)) { 2415 if (m2 == m1) continue; 2416 //if (i) the signature of 'sym' is not a subsignature of m1 (seen as 2417 //a member of 'site') and (ii) m1 has the same erasure as m2, issue an error 2418 if (!types.isSubSignature(sym.type, types.memberType(site, m2), allowStrictMethodClashCheck) && 2419 types.hasSameArgs(m2.erasure(types), m1.erasure(types))) { 2420 sym.flags_field |= CLASH; 2421 String key = m1 == sym ? 2422 "name.clash.same.erasure.no.override" : 2423 "name.clash.same.erasure.no.override.1"; 2424 log.error(pos, 2425 key, 2426 sym, sym.location(), 2427 m2, m2.location(), 2428 m1, m1.location()); 2429 return; 2430 } 2431 } 2432 } 2433 2434 if (!overridesAny) { 2435 for (MethodSymbol m: potentiallyAmbiguousList) { 2436 checkPotentiallyAmbiguousOverloads(pos, site, sym, m); 2437 } 2438 } 2439 } 2440 2441 /** Check that all static methods accessible from 'site' are 2442 * mutually compatible (JLS 8.4.8). 2443 * 2444 * @param pos Position to be used for error reporting. 2445 * @param site The class whose methods are checked. 2446 * @param sym The method symbol to be checked. 2447 */ 2448 void checkHideClashes(DiagnosticPosition pos, Type site, MethodSymbol sym) { 2449 ClashFilter cf = new ClashFilter(site); 2450 //for each method m1 that is a member of 'site'... 2451 for (Symbol s : types.membersClosure(site, true).getSymbolsByName(sym.name, cf)) { 2452 //if (i) the signature of 'sym' is not a subsignature of m1 (seen as 2453 //a member of 'site') and (ii) 'sym' has the same erasure as m1, issue an error 2454 if (!types.isSubSignature(sym.type, types.memberType(site, s), allowStrictMethodClashCheck)) { 2455 if (types.hasSameArgs(s.erasure(types), sym.erasure(types))) { 2456 log.error(pos, 2457 "name.clash.same.erasure.no.hide", 2458 sym, sym.location(), 2459 s, s.location()); 2460 return; 2461 } else { 2462 checkPotentiallyAmbiguousOverloads(pos, site, sym, (MethodSymbol)s); 2463 } 2464 } 2465 } 2466 } 2467 2468 //where 2469 private class ClashFilter implements Filter<Symbol> { 2470 2471 Type site; 2472 2473 ClashFilter(Type site) { 2474 this.site = site; 2475 } 2476 2477 boolean shouldSkip(Symbol s) { 2478 return (s.flags() & CLASH) != 0 && 2479 s.owner == site.tsym; 2480 } 2481 2482 public boolean accepts(Symbol s) { 2483 return s.kind == MTH && 2484 (s.flags() & SYNTHETIC) == 0 && 2485 !shouldSkip(s) && 2486 s.isInheritedIn(site.tsym, types) && 2487 !s.isConstructor(); 2488 } 2489 } 2490 2491 void checkDefaultMethodClashes(DiagnosticPosition pos, Type site) { 2492 DefaultMethodClashFilter dcf = new DefaultMethodClashFilter(site); 2493 for (Symbol m : types.membersClosure(site, false).getSymbols(dcf)) { 2494 Assert.check(m.kind == MTH); 2495 List<MethodSymbol> prov = types.interfaceCandidates(site, (MethodSymbol)m); 2496 if (prov.size() > 1) { 2497 ListBuffer<Symbol> abstracts = new ListBuffer<>(); 2498 ListBuffer<Symbol> defaults = new ListBuffer<>(); 2499 for (MethodSymbol provSym : prov) { 2500 if ((provSym.flags() & DEFAULT) != 0) { 2501 defaults = defaults.append(provSym); 2502 } else if ((provSym.flags() & ABSTRACT) != 0) { 2503 abstracts = abstracts.append(provSym); 2504 } 2505 if (defaults.nonEmpty() && defaults.size() + abstracts.size() >= 2) { 2506 //strong semantics - issue an error if two sibling interfaces 2507 //have two override-equivalent defaults - or if one is abstract 2508 //and the other is default 2509 String errKey; 2510 Symbol s1 = defaults.first(); 2511 Symbol s2; 2512 if (defaults.size() > 1) { 2513 errKey = "types.incompatible.unrelated.defaults"; 2514 s2 = defaults.toList().tail.head; 2515 } else { 2516 errKey = "types.incompatible.abstract.default"; 2517 s2 = abstracts.first(); 2518 } 2519 log.error(pos, errKey, 2520 Kinds.kindName(site.tsym), site, 2521 m.name, types.memberType(site, m).getParameterTypes(), 2522 s1.location(), s2.location()); 2523 break; 2524 } 2525 } 2526 } 2527 } 2528 } 2529 2530 //where 2531 private class DefaultMethodClashFilter implements Filter<Symbol> { 2532 2533 Type site; 2534 2535 DefaultMethodClashFilter(Type site) { 2536 this.site = site; 2537 } 2538 2539 public boolean accepts(Symbol s) { 2540 return s.kind == MTH && 2541 (s.flags() & DEFAULT) != 0 && 2542 s.isInheritedIn(site.tsym, types) && 2543 !s.isConstructor(); 2544 } 2545 } 2546 2547 /** 2548 * Report warnings for potentially ambiguous method declarations. Two declarations 2549 * are potentially ambiguous if they feature two unrelated functional interface 2550 * in same argument position (in which case, a call site passing an implicit 2551 * lambda would be ambiguous). 2552 */ 2553 void checkPotentiallyAmbiguousOverloads(DiagnosticPosition pos, Type site, 2554 MethodSymbol msym1, MethodSymbol msym2) { 2555 if (msym1 != msym2 && 2556 allowDefaultMethods && 2557 lint.isEnabled(LintCategory.OVERLOADS) && 2558 (msym1.flags() & POTENTIALLY_AMBIGUOUS) == 0 && 2559 (msym2.flags() & POTENTIALLY_AMBIGUOUS) == 0) { 2560 Type mt1 = types.memberType(site, msym1); 2561 Type mt2 = types.memberType(site, msym2); 2562 //if both generic methods, adjust type variables 2563 if (mt1.hasTag(FORALL) && mt2.hasTag(FORALL) && 2564 types.hasSameBounds((ForAll)mt1, (ForAll)mt2)) { 2565 mt2 = types.subst(mt2, ((ForAll)mt2).tvars, ((ForAll)mt1).tvars); 2566 } 2567 //expand varargs methods if needed 2568 int maxLength = Math.max(mt1.getParameterTypes().length(), mt2.getParameterTypes().length()); 2569 List<Type> args1 = rs.adjustArgs(mt1.getParameterTypes(), msym1, maxLength, true); 2570 List<Type> args2 = rs.adjustArgs(mt2.getParameterTypes(), msym2, maxLength, true); 2571 //if arities don't match, exit 2572 if (args1.length() != args2.length()) return; 2573 boolean potentiallyAmbiguous = false; 2574 while (args1.nonEmpty() && args2.nonEmpty()) { 2575 Type s = args1.head; 2576 Type t = args2.head; 2577 if (!types.isSubtype(t, s) && !types.isSubtype(s, t)) { 2578 if (types.isFunctionalInterface(s) && types.isFunctionalInterface(t) && 2579 types.findDescriptorType(s).getParameterTypes().length() > 0 && 2580 types.findDescriptorType(s).getParameterTypes().length() == 2581 types.findDescriptorType(t).getParameterTypes().length()) { 2582 potentiallyAmbiguous = true; 2583 } else { 2584 break; 2585 } 2586 } 2587 args1 = args1.tail; 2588 args2 = args2.tail; 2589 } 2590 if (potentiallyAmbiguous) { 2591 //we found two incompatible functional interfaces with same arity 2592 //this means a call site passing an implicit lambda would be ambigiuous 2593 msym1.flags_field |= POTENTIALLY_AMBIGUOUS; 2594 msym2.flags_field |= POTENTIALLY_AMBIGUOUS; 2595 log.warning(LintCategory.OVERLOADS, pos, "potentially.ambiguous.overload", 2596 msym1, msym1.location(), 2597 msym2, msym2.location()); 2598 return; 2599 } 2600 } 2601 } 2602 2603 void checkElemAccessFromSerializableLambda(final JCTree tree) { 2604 if (warnOnAccessToSensitiveMembers) { 2605 Symbol sym = TreeInfo.symbol(tree); 2606 if (!sym.kind.matches(KindSelector.VAL_MTH)) { 2607 return; 2608 } 2609 2610 if (sym.kind == VAR) { 2611 if ((sym.flags() & PARAMETER) != 0 || 2612 sym.isLocal() || 2613 sym.name == names._this || 2614 sym.name == names._super) { 2615 return; 2616 } 2617 } 2618 2619 if (!types.isSubtype(sym.owner.type, syms.serializableType) && 2620 isEffectivelyNonPublic(sym)) { 2621 log.warning(tree.pos(), 2622 "access.to.sensitive.member.from.serializable.element", sym); 2623 } 2624 } 2625 } 2626 2627 private boolean isEffectivelyNonPublic(Symbol sym) { 2628 if (sym.packge() == syms.rootPackage) { 2629 return false; 2630 } 2631 2632 while (sym.kind != PCK) { 2633 if ((sym.flags() & PUBLIC) == 0) { 2634 return true; 2635 } 2636 sym = sym.owner; 2637 } 2638 return false; 2639 } 2640 2641 /** Report a conflict between a user symbol and a synthetic symbol. 2642 */ 2643 private void syntheticError(DiagnosticPosition pos, Symbol sym) { 2644 if (!sym.type.isErroneous()) { 2645 log.error(pos, "synthetic.name.conflict", sym, sym.location()); 2646 } 2647 } 2648 2649 /** Check that class c does not implement directly or indirectly 2650 * the same parameterized interface with two different argument lists. 2651 * @param pos Position to be used for error reporting. 2652 * @param type The type whose interfaces are checked. 2653 */ 2654 void checkClassBounds(DiagnosticPosition pos, Type type) { 2655 checkClassBounds(pos, new HashMap<TypeSymbol,Type>(), type); 2656 } 2657//where 2658 /** Enter all interfaces of type `type' into the hash table `seensofar' 2659 * with their class symbol as key and their type as value. Make 2660 * sure no class is entered with two different types. 2661 */ 2662 void checkClassBounds(DiagnosticPosition pos, 2663 Map<TypeSymbol,Type> seensofar, 2664 Type type) { 2665 if (type.isErroneous()) return; 2666 for (List<Type> l = types.interfaces(type); l.nonEmpty(); l = l.tail) { 2667 Type it = l.head; 2668 Type oldit = seensofar.put(it.tsym, it); 2669 if (oldit != null) { 2670 List<Type> oldparams = oldit.allparams(); 2671 List<Type> newparams = it.allparams(); 2672 if (!types.containsTypeEquivalent(oldparams, newparams)) 2673 log.error(pos, "cant.inherit.diff.arg", 2674 it.tsym, Type.toString(oldparams), 2675 Type.toString(newparams)); 2676 } 2677 checkClassBounds(pos, seensofar, it); 2678 } 2679 Type st = types.supertype(type); 2680 if (st != Type.noType) checkClassBounds(pos, seensofar, st); 2681 } 2682 2683 /** Enter interface into into set. 2684 * If it existed already, issue a "repeated interface" error. 2685 */ 2686 void checkNotRepeated(DiagnosticPosition pos, Type it, Set<Type> its) { 2687 if (its.contains(it)) 2688 log.error(pos, "repeated.interface"); 2689 else { 2690 its.add(it); 2691 } 2692 } 2693 2694/* ************************************************************************* 2695 * Check annotations 2696 **************************************************************************/ 2697 2698 /** 2699 * Recursively validate annotations values 2700 */ 2701 void validateAnnotationTree(JCTree tree) { 2702 class AnnotationValidator extends TreeScanner { 2703 @Override 2704 public void visitAnnotation(JCAnnotation tree) { 2705 if (!tree.type.isErroneous()) { 2706 super.visitAnnotation(tree); 2707 validateAnnotation(tree); 2708 } 2709 } 2710 } 2711 tree.accept(new AnnotationValidator()); 2712 } 2713 2714 /** 2715 * {@literal 2716 * Annotation types are restricted to primitives, String, an 2717 * enum, an annotation, Class, Class<?>, Class<? extends 2718 * Anything>, arrays of the preceding. 2719 * } 2720 */ 2721 void validateAnnotationType(JCTree restype) { 2722 // restype may be null if an error occurred, so don't bother validating it 2723 if (restype != null) { 2724 validateAnnotationType(restype.pos(), restype.type); 2725 } 2726 } 2727 2728 void validateAnnotationType(DiagnosticPosition pos, Type type) { 2729 if (type.isPrimitive()) return; 2730 if (types.isSameType(type, syms.stringType)) return; 2731 if ((type.tsym.flags() & Flags.ENUM) != 0) return; 2732 if ((type.tsym.flags() & Flags.ANNOTATION) != 0) return; 2733 if (types.cvarLowerBound(type).tsym == syms.classType.tsym) return; 2734 if (types.isArray(type) && !types.isArray(types.elemtype(type))) { 2735 validateAnnotationType(pos, types.elemtype(type)); 2736 return; 2737 } 2738 log.error(pos, "invalid.annotation.member.type"); 2739 } 2740 2741 /** 2742 * "It is also a compile-time error if any method declared in an 2743 * annotation type has a signature that is override-equivalent to 2744 * that of any public or protected method declared in class Object 2745 * or in the interface annotation.Annotation." 2746 * 2747 * @jls 9.6 Annotation Types 2748 */ 2749 void validateAnnotationMethod(DiagnosticPosition pos, MethodSymbol m) { 2750 for (Type sup = syms.annotationType; sup.hasTag(CLASS); sup = types.supertype(sup)) { 2751 Scope s = sup.tsym.members(); 2752 for (Symbol sym : s.getSymbolsByName(m.name)) { 2753 if (sym.kind == MTH && 2754 (sym.flags() & (PUBLIC | PROTECTED)) != 0 && 2755 types.overrideEquivalent(m.type, sym.type)) 2756 log.error(pos, "intf.annotation.member.clash", sym, sup); 2757 } 2758 } 2759 } 2760 2761 /** Check the annotations of a symbol. 2762 */ 2763 public void validateAnnotations(List<JCAnnotation> annotations, Symbol s) { 2764 for (JCAnnotation a : annotations) 2765 validateAnnotation(a, s); 2766 } 2767 2768 /** Check the type annotations. 2769 */ 2770 public void validateTypeAnnotations(List<JCAnnotation> annotations, boolean isTypeParameter) { 2771 for (JCAnnotation a : annotations) 2772 validateTypeAnnotation(a, isTypeParameter); 2773 } 2774 2775 /** Check an annotation of a symbol. 2776 */ 2777 private void validateAnnotation(JCAnnotation a, Symbol s) { 2778 validateAnnotationTree(a); 2779 2780 if (!annotationApplicable(a, s)) 2781 log.error(a.pos(), "annotation.type.not.applicable"); 2782 2783 if (a.annotationType.type.tsym == syms.functionalInterfaceType.tsym) { 2784 if (s.kind != TYP) { 2785 log.error(a.pos(), "bad.functional.intf.anno"); 2786 } else if (!s.isInterface() || (s.flags() & ANNOTATION) != 0) { 2787 log.error(a.pos(), "bad.functional.intf.anno.1", diags.fragment("not.a.functional.intf", s)); 2788 } 2789 } 2790 } 2791 2792 public void validateTypeAnnotation(JCAnnotation a, boolean isTypeParameter) { 2793 Assert.checkNonNull(a.type); 2794 validateAnnotationTree(a); 2795 2796 if (a.hasTag(TYPE_ANNOTATION) && 2797 !a.annotationType.type.isErroneous() && 2798 !isTypeAnnotation(a, isTypeParameter)) { 2799 log.error(a.pos(), Errors.AnnotationTypeNotApplicableToType(a.type)); 2800 } 2801 } 2802 2803 /** 2804 * Validate the proposed container 'repeatable' on the 2805 * annotation type symbol 's'. Report errors at position 2806 * 'pos'. 2807 * 2808 * @param s The (annotation)type declaration annotated with a @Repeatable 2809 * @param repeatable the @Repeatable on 's' 2810 * @param pos where to report errors 2811 */ 2812 public void validateRepeatable(TypeSymbol s, Attribute.Compound repeatable, DiagnosticPosition pos) { 2813 Assert.check(types.isSameType(repeatable.type, syms.repeatableType)); 2814 2815 Type t = null; 2816 List<Pair<MethodSymbol,Attribute>> l = repeatable.values; 2817 if (!l.isEmpty()) { 2818 Assert.check(l.head.fst.name == names.value); 2819 t = ((Attribute.Class)l.head.snd).getValue(); 2820 } 2821 2822 if (t == null) { 2823 // errors should already have been reported during Annotate 2824 return; 2825 } 2826 2827 validateValue(t.tsym, s, pos); 2828 validateRetention(t.tsym, s, pos); 2829 validateDocumented(t.tsym, s, pos); 2830 validateInherited(t.tsym, s, pos); 2831 validateTarget(t.tsym, s, pos); 2832 validateDefault(t.tsym, pos); 2833 } 2834 2835 private void validateValue(TypeSymbol container, TypeSymbol contained, DiagnosticPosition pos) { 2836 Symbol sym = container.members().findFirst(names.value); 2837 if (sym != null && sym.kind == MTH) { 2838 MethodSymbol m = (MethodSymbol) sym; 2839 Type ret = m.getReturnType(); 2840 if (!(ret.hasTag(ARRAY) && types.isSameType(((ArrayType)ret).elemtype, contained.type))) { 2841 log.error(pos, "invalid.repeatable.annotation.value.return", 2842 container, ret, types.makeArrayType(contained.type)); 2843 } 2844 } else { 2845 log.error(pos, "invalid.repeatable.annotation.no.value", container); 2846 } 2847 } 2848 2849 private void validateRetention(TypeSymbol container, TypeSymbol contained, DiagnosticPosition pos) { 2850 Attribute.RetentionPolicy containerRetention = types.getRetention(container); 2851 Attribute.RetentionPolicy containedRetention = types.getRetention(contained); 2852 2853 boolean error = false; 2854 switch (containedRetention) { 2855 case RUNTIME: 2856 if (containerRetention != Attribute.RetentionPolicy.RUNTIME) { 2857 error = true; 2858 } 2859 break; 2860 case CLASS: 2861 if (containerRetention == Attribute.RetentionPolicy.SOURCE) { 2862 error = true; 2863 } 2864 } 2865 if (error ) { 2866 log.error(pos, "invalid.repeatable.annotation.retention", 2867 container, containerRetention, 2868 contained, containedRetention); 2869 } 2870 } 2871 2872 private void validateDocumented(Symbol container, Symbol contained, DiagnosticPosition pos) { 2873 if (contained.attribute(syms.documentedType.tsym) != null) { 2874 if (container.attribute(syms.documentedType.tsym) == null) { 2875 log.error(pos, "invalid.repeatable.annotation.not.documented", container, contained); 2876 } 2877 } 2878 } 2879 2880 private void validateInherited(Symbol container, Symbol contained, DiagnosticPosition pos) { 2881 if (contained.attribute(syms.inheritedType.tsym) != null) { 2882 if (container.attribute(syms.inheritedType.tsym) == null) { 2883 log.error(pos, "invalid.repeatable.annotation.not.inherited", container, contained); 2884 } 2885 } 2886 } 2887 2888 private void validateTarget(TypeSymbol container, TypeSymbol contained, DiagnosticPosition pos) { 2889 // The set of targets the container is applicable to must be a subset 2890 // (with respect to annotation target semantics) of the set of targets 2891 // the contained is applicable to. The target sets may be implicit or 2892 // explicit. 2893 2894 Set<Name> containerTargets; 2895 Attribute.Array containerTarget = getAttributeTargetAttribute(container); 2896 if (containerTarget == null) { 2897 containerTargets = getDefaultTargetSet(); 2898 } else { 2899 containerTargets = new HashSet<>(); 2900 for (Attribute app : containerTarget.values) { 2901 if (!(app instanceof Attribute.Enum)) { 2902 continue; // recovery 2903 } 2904 Attribute.Enum e = (Attribute.Enum)app; 2905 containerTargets.add(e.value.name); 2906 } 2907 } 2908 2909 Set<Name> containedTargets; 2910 Attribute.Array containedTarget = getAttributeTargetAttribute(contained); 2911 if (containedTarget == null) { 2912 containedTargets = getDefaultTargetSet(); 2913 } else { 2914 containedTargets = new HashSet<>(); 2915 for (Attribute app : containedTarget.values) { 2916 if (!(app instanceof Attribute.Enum)) { 2917 continue; // recovery 2918 } 2919 Attribute.Enum e = (Attribute.Enum)app; 2920 containedTargets.add(e.value.name); 2921 } 2922 } 2923 2924 if (!isTargetSubsetOf(containerTargets, containedTargets)) { 2925 log.error(pos, "invalid.repeatable.annotation.incompatible.target", container, contained); 2926 } 2927 } 2928 2929 /* get a set of names for the default target */ 2930 private Set<Name> getDefaultTargetSet() { 2931 if (defaultTargets == null) { 2932 Set<Name> targets = new HashSet<>(); 2933 targets.add(names.ANNOTATION_TYPE); 2934 targets.add(names.CONSTRUCTOR); 2935 targets.add(names.FIELD); 2936 targets.add(names.LOCAL_VARIABLE); 2937 targets.add(names.METHOD); 2938 targets.add(names.PACKAGE); 2939 targets.add(names.PARAMETER); 2940 targets.add(names.TYPE); 2941 2942 defaultTargets = java.util.Collections.unmodifiableSet(targets); 2943 } 2944 2945 return defaultTargets; 2946 } 2947 private Set<Name> defaultTargets; 2948 2949 2950 /** Checks that s is a subset of t, with respect to ElementType 2951 * semantics, specifically {ANNOTATION_TYPE} is a subset of {TYPE}, 2952 * and {TYPE_USE} covers the set {ANNOTATION_TYPE, TYPE, TYPE_USE, 2953 * TYPE_PARAMETER}. 2954 */ 2955 private boolean isTargetSubsetOf(Set<Name> s, Set<Name> t) { 2956 // Check that all elements in s are present in t 2957 for (Name n2 : s) { 2958 boolean currentElementOk = false; 2959 for (Name n1 : t) { 2960 if (n1 == n2) { 2961 currentElementOk = true; 2962 break; 2963 } else if (n1 == names.TYPE && n2 == names.ANNOTATION_TYPE) { 2964 currentElementOk = true; 2965 break; 2966 } else if (n1 == names.TYPE_USE && 2967 (n2 == names.TYPE || 2968 n2 == names.ANNOTATION_TYPE || 2969 n2 == names.TYPE_PARAMETER)) { 2970 currentElementOk = true; 2971 break; 2972 } 2973 } 2974 if (!currentElementOk) 2975 return false; 2976 } 2977 return true; 2978 } 2979 2980 private void validateDefault(Symbol container, DiagnosticPosition pos) { 2981 // validate that all other elements of containing type has defaults 2982 Scope scope = container.members(); 2983 for(Symbol elm : scope.getSymbols()) { 2984 if (elm.name != names.value && 2985 elm.kind == MTH && 2986 ((MethodSymbol)elm).defaultValue == null) { 2987 log.error(pos, 2988 "invalid.repeatable.annotation.elem.nondefault", 2989 container, 2990 elm); 2991 } 2992 } 2993 } 2994 2995 /** Is s a method symbol that overrides a method in a superclass? */ 2996 boolean isOverrider(Symbol s) { 2997 if (s.kind != MTH || s.isStatic()) 2998 return false; 2999 MethodSymbol m = (MethodSymbol)s; 3000 TypeSymbol owner = (TypeSymbol)m.owner; 3001 for (Type sup : types.closure(owner.type)) { 3002 if (sup == owner.type) 3003 continue; // skip "this" 3004 Scope scope = sup.tsym.members(); 3005 for (Symbol sym : scope.getSymbolsByName(m.name)) { 3006 if (!sym.isStatic() && m.overrides(sym, owner, types, true)) 3007 return true; 3008 } 3009 } 3010 return false; 3011 } 3012 3013 /** Is the annotation applicable to types? */ 3014 protected boolean isTypeAnnotation(JCAnnotation a, boolean isTypeParameter) { 3015 List<Attribute> targets = typeAnnotations.annotationTargets(a.annotationType.type.tsym); 3016 return (targets == null) ? 3017 false : 3018 targets.stream() 3019 .anyMatch(attr -> isTypeAnnotation(attr, isTypeParameter)); 3020 } 3021 //where 3022 boolean isTypeAnnotation(Attribute a, boolean isTypeParameter) { 3023 Attribute.Enum e = (Attribute.Enum)a; 3024 return (e.value.name == names.TYPE_USE || 3025 (isTypeParameter && e.value.name == names.TYPE_PARAMETER)); 3026 } 3027 3028 /** Is the annotation applicable to the symbol? */ 3029 boolean annotationApplicable(JCAnnotation a, Symbol s) { 3030 Attribute.Array arr = getAttributeTargetAttribute(a.annotationType.type.tsym); 3031 Name[] targets; 3032 3033 if (arr == null) { 3034 targets = defaultTargetMetaInfo(a, s); 3035 } else { 3036 // TODO: can we optimize this? 3037 targets = new Name[arr.values.length]; 3038 for (int i=0; i<arr.values.length; ++i) { 3039 Attribute app = arr.values[i]; 3040 if (!(app instanceof Attribute.Enum)) { 3041 return true; // recovery 3042 } 3043 Attribute.Enum e = (Attribute.Enum) app; 3044 targets[i] = e.value.name; 3045 } 3046 } 3047 for (Name target : targets) { 3048 if (target == names.TYPE) { 3049 if (s.kind == TYP) 3050 return true; 3051 } else if (target == names.FIELD) { 3052 if (s.kind == VAR && s.owner.kind != MTH) 3053 return true; 3054 } else if (target == names.METHOD) { 3055 if (s.kind == MTH && !s.isConstructor()) 3056 return true; 3057 } else if (target == names.PARAMETER) { 3058 if (s.kind == VAR && s.owner.kind == MTH && 3059 (s.flags() & PARAMETER) != 0) { 3060 return true; 3061 } 3062 } else if (target == names.CONSTRUCTOR) { 3063 if (s.kind == MTH && s.isConstructor()) 3064 return true; 3065 } else if (target == names.LOCAL_VARIABLE) { 3066 if (s.kind == VAR && s.owner.kind == MTH && 3067 (s.flags() & PARAMETER) == 0) { 3068 return true; 3069 } 3070 } else if (target == names.ANNOTATION_TYPE) { 3071 if (s.kind == TYP && (s.flags() & ANNOTATION) != 0) { 3072 return true; 3073 } 3074 } else if (target == names.PACKAGE) { 3075 if (s.kind == PCK) 3076 return true; 3077 } else if (target == names.TYPE_USE) { 3078 if (s.kind == TYP || s.kind == VAR || 3079 (s.kind == MTH && !s.isConstructor() && 3080 !s.type.getReturnType().hasTag(VOID)) || 3081 (s.kind == MTH && s.isConstructor())) { 3082 return true; 3083 } 3084 } else if (target == names.TYPE_PARAMETER) { 3085 if (s.kind == TYP && s.type.hasTag(TYPEVAR)) 3086 return true; 3087 } else 3088 return true; // Unknown ElementType. This should be an error at declaration site, 3089 // assume applicable. 3090 } 3091 return false; 3092 } 3093 3094 3095 Attribute.Array getAttributeTargetAttribute(TypeSymbol s) { 3096 Attribute.Compound atTarget = s.getAnnotationTypeMetadata().getTarget(); 3097 if (atTarget == null) return null; // ok, is applicable 3098 Attribute atValue = atTarget.member(names.value); 3099 if (!(atValue instanceof Attribute.Array)) return null; // error recovery 3100 return (Attribute.Array) atValue; 3101 } 3102 3103 private final Name[] dfltTargetMeta; 3104 private Name[] defaultTargetMetaInfo(JCAnnotation a, Symbol s) { 3105 return dfltTargetMeta; 3106 } 3107 3108 /** Check an annotation value. 3109 * 3110 * @param a The annotation tree to check 3111 * @return true if this annotation tree is valid, otherwise false 3112 */ 3113 public boolean validateAnnotationDeferErrors(JCAnnotation a) { 3114 boolean res = false; 3115 final Log.DiagnosticHandler diagHandler = new Log.DiscardDiagnosticHandler(log); 3116 try { 3117 res = validateAnnotation(a); 3118 } finally { 3119 log.popDiagnosticHandler(diagHandler); 3120 } 3121 return res; 3122 } 3123 3124 private boolean validateAnnotation(JCAnnotation a) { 3125 boolean isValid = true; 3126 AnnotationTypeMetadata metadata = a.annotationType.type.tsym.getAnnotationTypeMetadata(); 3127 3128 // collect an inventory of the annotation elements 3129 Set<MethodSymbol> elements = metadata.getAnnotationElements(); 3130 3131 // remove the ones that are assigned values 3132 for (JCTree arg : a.args) { 3133 if (!arg.hasTag(ASSIGN)) continue; // recovery 3134 JCAssign assign = (JCAssign)arg; 3135 Symbol m = TreeInfo.symbol(assign.lhs); 3136 if (m == null || m.type.isErroneous()) continue; 3137 if (!elements.remove(m)) { 3138 isValid = false; 3139 log.error(assign.lhs.pos(), "duplicate.annotation.member.value", 3140 m.name, a.type); 3141 } 3142 } 3143 3144 // all the remaining ones better have default values 3145 List<Name> missingDefaults = List.nil(); 3146 Set<MethodSymbol> membersWithDefault = metadata.getAnnotationElementsWithDefault(); 3147 for (MethodSymbol m : elements) { 3148 if (m.type.isErroneous()) 3149 continue; 3150 3151 if (!membersWithDefault.contains(m)) 3152 missingDefaults = missingDefaults.append(m.name); 3153 } 3154 missingDefaults = missingDefaults.reverse(); 3155 if (missingDefaults.nonEmpty()) { 3156 isValid = false; 3157 String key = (missingDefaults.size() > 1) 3158 ? "annotation.missing.default.value.1" 3159 : "annotation.missing.default.value"; 3160 log.error(a.pos(), key, a.type, missingDefaults); 3161 } 3162 3163 return isValid && validateTargetAnnotationValue(a); 3164 } 3165 3166 /* Validate the special java.lang.annotation.Target annotation */ 3167 boolean validateTargetAnnotationValue(JCAnnotation a) { 3168 // special case: java.lang.annotation.Target must not have 3169 // repeated values in its value member 3170 if (a.annotationType.type.tsym != syms.annotationTargetType.tsym || 3171 a.args.tail == null) 3172 return true; 3173 3174 boolean isValid = true; 3175 if (!a.args.head.hasTag(ASSIGN)) return false; // error recovery 3176 JCAssign assign = (JCAssign) a.args.head; 3177 Symbol m = TreeInfo.symbol(assign.lhs); 3178 if (m.name != names.value) return false; 3179 JCTree rhs = assign.rhs; 3180 if (!rhs.hasTag(NEWARRAY)) return false; 3181 JCNewArray na = (JCNewArray) rhs; 3182 Set<Symbol> targets = new HashSet<>(); 3183 for (JCTree elem : na.elems) { 3184 if (!targets.add(TreeInfo.symbol(elem))) { 3185 isValid = false; 3186 log.error(elem.pos(), "repeated.annotation.target"); 3187 } 3188 } 3189 return isValid; 3190 } 3191 3192 void checkDeprecatedAnnotation(DiagnosticPosition pos, Symbol s) { 3193 if (lint.isEnabled(LintCategory.DEP_ANN) && 3194 (s.flags() & DEPRECATED) != 0 && 3195 !syms.deprecatedType.isErroneous() && 3196 s.attribute(syms.deprecatedType.tsym) == null) { 3197 log.warning(LintCategory.DEP_ANN, 3198 pos, "missing.deprecated.annotation"); 3199 } 3200 // Note: @Deprecated has no effect on local variables, parameters and package decls. 3201 if (lint.isEnabled(LintCategory.DEPRECATION)) { 3202 if (!syms.deprecatedType.isErroneous() && s.attribute(syms.deprecatedType.tsym) != null) { 3203 switch (s.getKind()) { 3204 case LOCAL_VARIABLE: 3205 case PACKAGE: 3206 case PARAMETER: 3207 case RESOURCE_VARIABLE: 3208 case EXCEPTION_PARAMETER: 3209 log.warning(LintCategory.DEPRECATION, pos, 3210 "deprecated.annotation.has.no.effect", Kinds.kindName(s)); 3211 break; 3212 } 3213 } 3214 } 3215 } 3216 3217 void checkDeprecated(final DiagnosticPosition pos, final Symbol other, final Symbol s) { 3218 if ((s.flags() & DEPRECATED) != 0 && 3219 (other.flags() & DEPRECATED) == 0 && 3220 s.outermostClass() != other.outermostClass()) { 3221 deferredLintHandler.report(new DeferredLintHandler.LintLogger() { 3222 @Override 3223 public void report() { 3224 warnDeprecated(pos, s); 3225 } 3226 }); 3227 } 3228 } 3229 3230 void checkSunAPI(final DiagnosticPosition pos, final Symbol s) { 3231 if ((s.flags() & PROPRIETARY) != 0) { 3232 deferredLintHandler.report(() -> { 3233 log.mandatoryWarning(pos, "sun.proprietary", s); 3234 }); 3235 } 3236 } 3237 3238 void checkProfile(final DiagnosticPosition pos, final Symbol s) { 3239 if (profile != Profile.DEFAULT && (s.flags() & NOT_IN_PROFILE) != 0) { 3240 log.error(pos, "not.in.profile", s, profile); 3241 } 3242 } 3243 3244/* ************************************************************************* 3245 * Check for recursive annotation elements. 3246 **************************************************************************/ 3247 3248 /** Check for cycles in the graph of annotation elements. 3249 */ 3250 void checkNonCyclicElements(JCClassDecl tree) { 3251 if ((tree.sym.flags_field & ANNOTATION) == 0) return; 3252 Assert.check((tree.sym.flags_field & LOCKED) == 0); 3253 try { 3254 tree.sym.flags_field |= LOCKED; 3255 for (JCTree def : tree.defs) { 3256 if (!def.hasTag(METHODDEF)) continue; 3257 JCMethodDecl meth = (JCMethodDecl)def; 3258 checkAnnotationResType(meth.pos(), meth.restype.type); 3259 } 3260 } finally { 3261 tree.sym.flags_field &= ~LOCKED; 3262 tree.sym.flags_field |= ACYCLIC_ANN; 3263 } 3264 } 3265 3266 void checkNonCyclicElementsInternal(DiagnosticPosition pos, TypeSymbol tsym) { 3267 if ((tsym.flags_field & ACYCLIC_ANN) != 0) 3268 return; 3269 if ((tsym.flags_field & LOCKED) != 0) { 3270 log.error(pos, "cyclic.annotation.element"); 3271 return; 3272 } 3273 try { 3274 tsym.flags_field |= LOCKED; 3275 for (Symbol s : tsym.members().getSymbols(NON_RECURSIVE)) { 3276 if (s.kind != MTH) 3277 continue; 3278 checkAnnotationResType(pos, ((MethodSymbol)s).type.getReturnType()); 3279 } 3280 } finally { 3281 tsym.flags_field &= ~LOCKED; 3282 tsym.flags_field |= ACYCLIC_ANN; 3283 } 3284 } 3285 3286 void checkAnnotationResType(DiagnosticPosition pos, Type type) { 3287 switch (type.getTag()) { 3288 case CLASS: 3289 if ((type.tsym.flags() & ANNOTATION) != 0) 3290 checkNonCyclicElementsInternal(pos, type.tsym); 3291 break; 3292 case ARRAY: 3293 checkAnnotationResType(pos, types.elemtype(type)); 3294 break; 3295 default: 3296 break; // int etc 3297 } 3298 } 3299 3300/* ************************************************************************* 3301 * Check for cycles in the constructor call graph. 3302 **************************************************************************/ 3303 3304 /** Check for cycles in the graph of constructors calling other 3305 * constructors. 3306 */ 3307 void checkCyclicConstructors(JCClassDecl tree) { 3308 Map<Symbol,Symbol> callMap = new HashMap<>(); 3309 3310 // enter each constructor this-call into the map 3311 for (List<JCTree> l = tree.defs; l.nonEmpty(); l = l.tail) { 3312 JCMethodInvocation app = TreeInfo.firstConstructorCall(l.head); 3313 if (app == null) continue; 3314 JCMethodDecl meth = (JCMethodDecl) l.head; 3315 if (TreeInfo.name(app.meth) == names._this) { 3316 callMap.put(meth.sym, TreeInfo.symbol(app.meth)); 3317 } else { 3318 meth.sym.flags_field |= ACYCLIC; 3319 } 3320 } 3321 3322 // Check for cycles in the map 3323 Symbol[] ctors = new Symbol[0]; 3324 ctors = callMap.keySet().toArray(ctors); 3325 for (Symbol caller : ctors) { 3326 checkCyclicConstructor(tree, caller, callMap); 3327 } 3328 } 3329 3330 /** Look in the map to see if the given constructor is part of a 3331 * call cycle. 3332 */ 3333 private void checkCyclicConstructor(JCClassDecl tree, Symbol ctor, 3334 Map<Symbol,Symbol> callMap) { 3335 if (ctor != null && (ctor.flags_field & ACYCLIC) == 0) { 3336 if ((ctor.flags_field & LOCKED) != 0) { 3337 log.error(TreeInfo.diagnosticPositionFor(ctor, tree), 3338 "recursive.ctor.invocation"); 3339 } else { 3340 ctor.flags_field |= LOCKED; 3341 checkCyclicConstructor(tree, callMap.remove(ctor), callMap); 3342 ctor.flags_field &= ~LOCKED; 3343 } 3344 ctor.flags_field |= ACYCLIC; 3345 } 3346 } 3347 3348/* ************************************************************************* 3349 * Miscellaneous 3350 **************************************************************************/ 3351 3352 /** 3353 * Check for division by integer constant zero 3354 * @param pos Position for error reporting. 3355 * @param operator The operator for the expression 3356 * @param operand The right hand operand for the expression 3357 */ 3358 void checkDivZero(final DiagnosticPosition pos, Symbol operator, Type operand) { 3359 if (operand.constValue() != null 3360 && operand.getTag().isSubRangeOf(LONG) 3361 && ((Number) (operand.constValue())).longValue() == 0) { 3362 int opc = ((OperatorSymbol)operator).opcode; 3363 if (opc == ByteCodes.idiv || opc == ByteCodes.imod 3364 || opc == ByteCodes.ldiv || opc == ByteCodes.lmod) { 3365 deferredLintHandler.report(new DeferredLintHandler.LintLogger() { 3366 @Override 3367 public void report() { 3368 warnDivZero(pos); 3369 } 3370 }); 3371 } 3372 } 3373 } 3374 3375 /** 3376 * Check for empty statements after if 3377 */ 3378 void checkEmptyIf(JCIf tree) { 3379 if (tree.thenpart.hasTag(SKIP) && tree.elsepart == null && 3380 lint.isEnabled(LintCategory.EMPTY)) 3381 log.warning(LintCategory.EMPTY, tree.thenpart.pos(), "empty.if"); 3382 } 3383 3384 /** Check that symbol is unique in given scope. 3385 * @param pos Position for error reporting. 3386 * @param sym The symbol. 3387 * @param s The scope. 3388 */ 3389 boolean checkUnique(DiagnosticPosition pos, Symbol sym, Scope s) { 3390 if (sym.type.isErroneous()) 3391 return true; 3392 if (sym.owner.name == names.any) return false; 3393 for (Symbol byName : s.getSymbolsByName(sym.name, NON_RECURSIVE)) { 3394 if (sym != byName && 3395 (byName.flags() & CLASH) == 0 && 3396 sym.kind == byName.kind && 3397 sym.name != names.error && 3398 (sym.kind != MTH || 3399 types.hasSameArgs(sym.type, byName.type) || 3400 types.hasSameArgs(types.erasure(sym.type), types.erasure(byName.type)))) { 3401 if ((sym.flags() & VARARGS) != (byName.flags() & VARARGS)) { 3402 varargsDuplicateError(pos, sym, byName); 3403 return true; 3404 } else if (sym.kind == MTH && !types.hasSameArgs(sym.type, byName.type, false)) { 3405 duplicateErasureError(pos, sym, byName); 3406 sym.flags_field |= CLASH; 3407 return true; 3408 } else { 3409 duplicateError(pos, byName); 3410 return false; 3411 } 3412 } 3413 } 3414 return true; 3415 } 3416 3417 /** Report duplicate declaration error. 3418 */ 3419 void duplicateErasureError(DiagnosticPosition pos, Symbol sym1, Symbol sym2) { 3420 if (!sym1.type.isErroneous() && !sym2.type.isErroneous()) { 3421 log.error(pos, "name.clash.same.erasure", sym1, sym2); 3422 } 3423 } 3424 3425 /**Check that types imported through the ordinary imports don't clash with types imported 3426 * by other (static or ordinary) imports. Note that two static imports may import two clashing 3427 * types without an error on the imports. 3428 * @param toplevel The toplevel tree for which the test should be performed. 3429 */ 3430 void checkImportsUnique(JCCompilationUnit toplevel) { 3431 WriteableScope ordinallyImportedSoFar = WriteableScope.create(toplevel.packge); 3432 WriteableScope staticallyImportedSoFar = WriteableScope.create(toplevel.packge); 3433 WriteableScope topLevelScope = toplevel.toplevelScope; 3434 3435 for (JCTree def : toplevel.defs) { 3436 if (!def.hasTag(IMPORT)) 3437 continue; 3438 3439 JCImport imp = (JCImport) def; 3440 3441 if (imp.importScope == null) 3442 continue; 3443 3444 for (Symbol sym : imp.importScope.getSymbols(sym -> sym.kind == TYP)) { 3445 if (imp.isStatic()) { 3446 checkUniqueImport(imp.pos(), ordinallyImportedSoFar, staticallyImportedSoFar, topLevelScope, sym, true); 3447 staticallyImportedSoFar.enter(sym); 3448 } else { 3449 checkUniqueImport(imp.pos(), ordinallyImportedSoFar, staticallyImportedSoFar, topLevelScope, sym, false); 3450 ordinallyImportedSoFar.enter(sym); 3451 } 3452 } 3453 3454 imp.importScope = null; 3455 } 3456 } 3457 3458 /** Check that single-type import is not already imported or top-level defined, 3459 * but make an exception for two single-type imports which denote the same type. 3460 * @param pos Position for error reporting. 3461 * @param ordinallyImportedSoFar A Scope containing types imported so far through 3462 * ordinary imports. 3463 * @param staticallyImportedSoFar A Scope containing types imported so far through 3464 * static imports. 3465 * @param topLevelScope The current file's top-level Scope 3466 * @param sym The symbol. 3467 * @param staticImport Whether or not this was a static import 3468 */ 3469 private boolean checkUniqueImport(DiagnosticPosition pos, Scope ordinallyImportedSoFar, 3470 Scope staticallyImportedSoFar, Scope topLevelScope, 3471 Symbol sym, boolean staticImport) { 3472 Filter<Symbol> duplicates = candidate -> candidate != sym && !candidate.type.isErroneous(); 3473 Symbol clashing = ordinallyImportedSoFar.findFirst(sym.name, duplicates); 3474 if (clashing == null && !staticImport) { 3475 clashing = staticallyImportedSoFar.findFirst(sym.name, duplicates); 3476 } 3477 if (clashing != null) { 3478 if (staticImport) 3479 log.error(pos, "already.defined.static.single.import", clashing); 3480 else 3481 log.error(pos, "already.defined.single.import", clashing); 3482 return false; 3483 } 3484 clashing = topLevelScope.findFirst(sym.name, duplicates); 3485 if (clashing != null) { 3486 log.error(pos, "already.defined.this.unit", clashing); 3487 return false; 3488 } 3489 return true; 3490 } 3491 3492 /** Check that a qualified name is in canonical form (for import decls). 3493 */ 3494 public void checkCanonical(JCTree tree) { 3495 if (!isCanonical(tree)) 3496 log.error(tree.pos(), "import.requires.canonical", 3497 TreeInfo.symbol(tree)); 3498 } 3499 // where 3500 private boolean isCanonical(JCTree tree) { 3501 while (tree.hasTag(SELECT)) { 3502 JCFieldAccess s = (JCFieldAccess) tree; 3503 if (s.sym.owner.name != TreeInfo.symbol(s.selected).name) 3504 return false; 3505 tree = s.selected; 3506 } 3507 return true; 3508 } 3509 3510 /** Check that an auxiliary class is not accessed from any other file than its own. 3511 */ 3512 void checkForBadAuxiliaryClassAccess(DiagnosticPosition pos, Env<AttrContext> env, ClassSymbol c) { 3513 if (lint.isEnabled(Lint.LintCategory.AUXILIARYCLASS) && 3514 (c.flags() & AUXILIARY) != 0 && 3515 rs.isAccessible(env, c) && 3516 !fileManager.isSameFile(c.sourcefile, env.toplevel.sourcefile)) 3517 { 3518 log.warning(pos, "auxiliary.class.accessed.from.outside.of.its.source.file", 3519 c, c.sourcefile); 3520 } 3521 } 3522 3523 private class ConversionWarner extends Warner { 3524 final String uncheckedKey; 3525 final Type found; 3526 final Type expected; 3527 public ConversionWarner(DiagnosticPosition pos, String uncheckedKey, Type found, Type expected) { 3528 super(pos); 3529 this.uncheckedKey = uncheckedKey; 3530 this.found = found; 3531 this.expected = expected; 3532 } 3533 3534 @Override 3535 public void warn(LintCategory lint) { 3536 boolean warned = this.warned; 3537 super.warn(lint); 3538 if (warned) return; // suppress redundant diagnostics 3539 switch (lint) { 3540 case UNCHECKED: 3541 Check.this.warnUnchecked(pos(), "prob.found.req", diags.fragment(uncheckedKey), found, expected); 3542 break; 3543 case VARARGS: 3544 if (method != null && 3545 method.attribute(syms.trustMeType.tsym) != null && 3546 isTrustMeAllowedOnMethod(method) && 3547 !types.isReifiable(method.type.getParameterTypes().last())) { 3548 Check.this.warnUnsafeVararg(pos(), "varargs.unsafe.use.varargs.param", method.params.last()); 3549 } 3550 break; 3551 default: 3552 throw new AssertionError("Unexpected lint: " + lint); 3553 } 3554 } 3555 } 3556 3557 public Warner castWarner(DiagnosticPosition pos, Type found, Type expected) { 3558 return new ConversionWarner(pos, "unchecked.cast.to.type", found, expected); 3559 } 3560 3561 public Warner convertWarner(DiagnosticPosition pos, Type found, Type expected) { 3562 return new ConversionWarner(pos, "unchecked.assign", found, expected); 3563 } 3564 3565 public void checkFunctionalInterface(JCClassDecl tree, ClassSymbol cs) { 3566 Compound functionalType = cs.attribute(syms.functionalInterfaceType.tsym); 3567 3568 if (functionalType != null) { 3569 try { 3570 types.findDescriptorSymbol((TypeSymbol)cs); 3571 } catch (Types.FunctionDescriptorLookupError ex) { 3572 DiagnosticPosition pos = tree.pos(); 3573 for (JCAnnotation a : tree.getModifiers().annotations) { 3574 if (a.annotationType.type.tsym == syms.functionalInterfaceType.tsym) { 3575 pos = a.pos(); 3576 break; 3577 } 3578 } 3579 log.error(pos, "bad.functional.intf.anno.1", ex.getDiagnostic()); 3580 } 3581 } 3582 } 3583 3584 public void checkImportsResolvable(final JCCompilationUnit toplevel) { 3585 for (final JCImport imp : toplevel.getImports()) { 3586 if (!imp.staticImport || !imp.qualid.hasTag(SELECT)) 3587 continue; 3588 final JCFieldAccess select = (JCFieldAccess) imp.qualid; 3589 final Symbol origin; 3590 if (select.name == names.asterisk || (origin = TreeInfo.symbol(select.selected)) == null || origin.kind != TYP) 3591 continue; 3592 3593 TypeSymbol site = (TypeSymbol) TreeInfo.symbol(select.selected); 3594 if (!checkTypeContainsImportableElement(site, site, toplevel.packge, select.name, new HashSet<Symbol>())) { 3595 log.error(imp.pos(), "cant.resolve.location", 3596 KindName.STATIC, 3597 select.name, List.<Type>nil(), List.<Type>nil(), 3598 Kinds.typeKindName(TreeInfo.symbol(select.selected).type), 3599 TreeInfo.symbol(select.selected).type); 3600 } 3601 } 3602 } 3603 3604 // Check that packages imported are in scope (JLS 7.4.3, 6.3, 6.5.3.1, 6.5.3.2) 3605 public void checkImportedPackagesObservable(final JCCompilationUnit toplevel) { 3606 OUTER: for (JCImport imp : toplevel.getImports()) { 3607 if (!imp.staticImport && TreeInfo.name(imp.qualid) == names.asterisk) { 3608 TypeSymbol tsym = ((JCFieldAccess)imp.qualid).selected.type.tsym; 3609 if (toplevel.modle.visiblePackages != null) { 3610 //TODO - unclear: selects like javax.* will get resolved from the current module 3611 //(as javax is not an exported package from any module). And as javax in the current 3612 //module typically does not contain any classes or subpackages, we need to go through 3613 //the visible packages to find a sub-package: 3614 for (PackageSymbol known : toplevel.modle.visiblePackages.values()) { 3615 if (Convert.packagePart(known.fullname) == tsym.flatName()) 3616 continue OUTER; 3617 } 3618 } 3619 if (tsym.kind == PCK && tsym.members().isEmpty() && !tsym.exists()) { 3620 log.error(DiagnosticFlag.RESOLVE_ERROR, imp.pos, "doesnt.exist", tsym); 3621 } 3622 } 3623 } 3624 } 3625 3626 private boolean checkTypeContainsImportableElement(TypeSymbol tsym, TypeSymbol origin, PackageSymbol packge, Name name, Set<Symbol> processed) { 3627 if (tsym == null || !processed.add(tsym)) 3628 return false; 3629 3630 // also search through inherited names 3631 if (checkTypeContainsImportableElement(types.supertype(tsym.type).tsym, origin, packge, name, processed)) 3632 return true; 3633 3634 for (Type t : types.interfaces(tsym.type)) 3635 if (checkTypeContainsImportableElement(t.tsym, origin, packge, name, processed)) 3636 return true; 3637 3638 for (Symbol sym : tsym.members().getSymbolsByName(name)) { 3639 if (sym.isStatic() && 3640 importAccessible(sym, packge) && 3641 sym.isMemberOf(origin, types)) { 3642 return true; 3643 } 3644 } 3645 3646 return false; 3647 } 3648 3649 // is the sym accessible everywhere in packge? 3650 public boolean importAccessible(Symbol sym, PackageSymbol packge) { 3651 try { 3652 int flags = (int)(sym.flags() & AccessFlags); 3653 switch (flags) { 3654 default: 3655 case PUBLIC: 3656 return true; 3657 case PRIVATE: 3658 return false; 3659 case 0: 3660 case PROTECTED: 3661 return sym.packge() == packge; 3662 } 3663 } catch (ClassFinder.BadClassFile err) { 3664 throw err; 3665 } catch (CompletionFailure ex) { 3666 return false; 3667 } 3668 } 3669 3670} 3671