Check.java revision 2833:f683944ffa42
1/* 2 * Copyright (c) 1999, 2015, 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.jvm.*; 35import com.sun.tools.javac.tree.*; 36import com.sun.tools.javac.util.*; 37import com.sun.tools.javac.util.JCDiagnostic.DiagnosticPosition; 38import com.sun.tools.javac.util.List; 39 40import com.sun.tools.javac.code.Lint; 41import com.sun.tools.javac.code.Lint.LintCategory; 42import com.sun.tools.javac.code.Scope.CompoundScope; 43import com.sun.tools.javac.code.Scope.NamedImportScope; 44import com.sun.tools.javac.code.Scope.WriteableScope; 45import com.sun.tools.javac.code.Type.*; 46import com.sun.tools.javac.code.Symbol.*; 47import com.sun.tools.javac.comp.DeferredAttr.DeferredAttrContext; 48import com.sun.tools.javac.comp.Infer.InferenceContext; 49import com.sun.tools.javac.comp.Infer.FreeTypeListener; 50import com.sun.tools.javac.tree.JCTree.*; 51import com.sun.tools.javac.tree.JCTree.JCPolyExpression.*; 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 JCDiagnostic.Factory diags; 83 private boolean warnOnSyntheticConflicts; 84 private boolean suppressAbortOnBadClassFile; 85 private boolean enableSunApiLintControl; 86 private final JavaFileManager fileManager; 87 private final Profile profile; 88 private final boolean warnOnAccessToSensitiveMembers; 89 90 // The set of lint options currently in effect. It is initialized 91 // from the context, and then is set/reset as needed by Attr as it 92 // visits all the various parts of the trees during attribution. 93 private Lint lint; 94 95 // The method being analyzed in Attr - it is set/reset as needed by 96 // Attr as it visits new method declarations. 97 private MethodSymbol method; 98 99 public static Check instance(Context context) { 100 Check instance = context.get(checkKey); 101 if (instance == null) 102 instance = new Check(context); 103 return instance; 104 } 105 106 protected Check(Context context) { 107 context.put(checkKey, this); 108 109 names = Names.instance(context); 110 dfltTargetMeta = new Name[] { names.PACKAGE, names.TYPE, 111 names.FIELD, names.METHOD, names.CONSTRUCTOR, 112 names.ANNOTATION_TYPE, names.LOCAL_VARIABLE, names.PARAMETER}; 113 log = Log.instance(context); 114 rs = Resolve.instance(context); 115 syms = Symtab.instance(context); 116 enter = Enter.instance(context); 117 deferredAttr = DeferredAttr.instance(context); 118 infer = Infer.instance(context); 119 types = Types.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 = Source.instance(context); 126 allowSimplifiedVarargs = source.allowSimplifiedVarargs(); 127 allowDefaultMethods = source.allowDefaultMethods(); 128 allowStrictMethodClashCheck = source.allowStrictMethodClashCheck(); 129 allowPrivateSafeVarargs = source.allowPrivateSafeVarargs(); 130 complexInference = options.isSet("complexinference"); 131 warnOnSyntheticConflicts = options.isSet("warnOnSyntheticConflicts"); 132 suppressAbortOnBadClassFile = options.isSet("suppressAbortOnBadClassFile"); 133 enableSunApiLintControl = options.isSet("enableSunApiLintControl"); 134 warnOnAccessToSensitiveMembers = options.isSet("warnOnAccessToSensitiveMembers"); 135 136 Target target = Target.instance(context); 137 syntheticNameChar = target.syntheticNameChar(); 138 139 profile = Profile.instance(context); 140 141 boolean verboseDeprecated = lint.isEnabled(LintCategory.DEPRECATION); 142 boolean verboseUnchecked = lint.isEnabled(LintCategory.UNCHECKED); 143 boolean verboseSunApi = lint.isEnabled(LintCategory.SUNAPI); 144 boolean enforceMandatoryWarnings = true; 145 146 deprecationHandler = new MandatoryWarningHandler(log, verboseDeprecated, 147 enforceMandatoryWarnings, "deprecated", LintCategory.DEPRECATION); 148 uncheckedHandler = new MandatoryWarningHandler(log, verboseUnchecked, 149 enforceMandatoryWarnings, "unchecked", LintCategory.UNCHECKED); 150 sunApiHandler = new MandatoryWarningHandler(log, verboseSunApi, 151 enforceMandatoryWarnings, "sunapi", null); 152 153 deferredLintHandler = DeferredLintHandler.instance(context); 154 } 155 156 /** Switch: simplified varargs enabled? 157 */ 158 boolean allowSimplifiedVarargs; 159 160 /** Switch: default methods enabled? 161 */ 162 boolean allowDefaultMethods; 163 164 /** Switch: should unrelated return types trigger a method clash? 165 */ 166 boolean allowStrictMethodClashCheck; 167 168 /** Switch: can the @SafeVarargs annotation be applied to private methods? 169 */ 170 boolean allowPrivateSafeVarargs; 171 172 /** Switch: -complexinference option set? 173 */ 174 boolean complexInference; 175 176 /** Character for synthetic names 177 */ 178 char syntheticNameChar; 179 180 /** A table mapping flat names of all compiled classes in this run to their 181 * symbols; maintained from outside. 182 */ 183 public Map<Name,ClassSymbol> compiled = new HashMap<>(); 184 185 /** A handler for messages about deprecated usage. 186 */ 187 private MandatoryWarningHandler deprecationHandler; 188 189 /** A handler for messages about unchecked or unsafe usage. 190 */ 191 private MandatoryWarningHandler uncheckedHandler; 192 193 /** A handler for messages about using proprietary API. 194 */ 195 private MandatoryWarningHandler sunApiHandler; 196 197 /** A handler for deferred lint warnings. 198 */ 199 private DeferredLintHandler deferredLintHandler; 200 201/* ************************************************************************* 202 * Errors and Warnings 203 **************************************************************************/ 204 205 Lint setLint(Lint newLint) { 206 Lint prev = lint; 207 lint = newLint; 208 return prev; 209 } 210 211 MethodSymbol setMethod(MethodSymbol newMethod) { 212 MethodSymbol prev = method; 213 method = newMethod; 214 return prev; 215 } 216 217 /** Warn about deprecated symbol. 218 * @param pos Position to be used for error reporting. 219 * @param sym The deprecated symbol. 220 */ 221 void warnDeprecated(DiagnosticPosition pos, Symbol sym) { 222 if (!lint.isSuppressed(LintCategory.DEPRECATION)) 223 deprecationHandler.report(pos, "has.been.deprecated", sym, sym.location()); 224 } 225 226 /** Warn about unchecked operation. 227 * @param pos Position to be used for error reporting. 228 * @param msg A string describing the problem. 229 */ 230 public void warnUnchecked(DiagnosticPosition pos, String msg, Object... args) { 231 if (!lint.isSuppressed(LintCategory.UNCHECKED)) 232 uncheckedHandler.report(pos, msg, args); 233 } 234 235 /** Warn about unsafe vararg method decl. 236 * @param pos Position to be used for error reporting. 237 */ 238 void warnUnsafeVararg(DiagnosticPosition pos, String key, Object... args) { 239 if (lint.isEnabled(LintCategory.VARARGS) && allowSimplifiedVarargs) 240 log.warning(LintCategory.VARARGS, pos, key, args); 241 } 242 243 /** Warn about using proprietary API. 244 * @param pos Position to be used for error reporting. 245 * @param msg A string describing the problem. 246 */ 247 public void warnSunApi(DiagnosticPosition pos, String msg, Object... args) { 248 if (!lint.isSuppressed(LintCategory.SUNAPI)) 249 sunApiHandler.report(pos, msg, args); 250 } 251 252 public void warnStatic(DiagnosticPosition pos, String msg, Object... args) { 253 if (lint.isEnabled(LintCategory.STATIC)) 254 log.warning(LintCategory.STATIC, pos, msg, args); 255 } 256 257 /** Warn about division by integer constant zero. 258 * @param pos Position to be used for error reporting. 259 */ 260 void warnDivZero(DiagnosticPosition pos) { 261 if (lint.isEnabled(LintCategory.DIVZERO)) 262 log.warning(LintCategory.DIVZERO, pos, "div.zero"); 263 } 264 265 /** 266 * Report any deferred diagnostics. 267 */ 268 public void reportDeferredDiagnostics() { 269 deprecationHandler.reportDeferredDiagnostic(); 270 uncheckedHandler.reportDeferredDiagnostic(); 271 sunApiHandler.reportDeferredDiagnostic(); 272 } 273 274 275 /** Report a failure to complete a class. 276 * @param pos Position to be used for error reporting. 277 * @param ex The failure to report. 278 */ 279 public Type completionError(DiagnosticPosition pos, CompletionFailure ex) { 280 log.error(JCDiagnostic.DiagnosticFlag.NON_DEFERRABLE, pos, "cant.access", ex.sym, ex.getDetailValue()); 281 if (ex instanceof ClassFinder.BadClassFile 282 && !suppressAbortOnBadClassFile) throw new Abort(); 283 else return syms.errType; 284 } 285 286 /** Report an error that wrong type tag was found. 287 * @param pos Position to be used for error reporting. 288 * @param required An internationalized string describing the type tag 289 * required. 290 * @param found The type that was found. 291 */ 292 Type typeTagError(DiagnosticPosition pos, Object required, Object found) { 293 // this error used to be raised by the parser, 294 // but has been delayed to this point: 295 if (found instanceof Type && ((Type)found).hasTag(VOID)) { 296 log.error(pos, "illegal.start.of.type"); 297 return syms.errType; 298 } 299 log.error(pos, "type.found.req", found, required); 300 return types.createErrorType(found instanceof Type ? (Type)found : syms.errType); 301 } 302 303 /** Report an error that symbol cannot be referenced before super 304 * has been called. 305 * @param pos Position to be used for error reporting. 306 * @param sym The referenced symbol. 307 */ 308 void earlyRefError(DiagnosticPosition pos, Symbol sym) { 309 log.error(pos, "cant.ref.before.ctor.called", sym); 310 } 311 312 /** Report duplicate declaration error. 313 */ 314 void duplicateError(DiagnosticPosition pos, Symbol sym) { 315 if (!sym.type.isErroneous()) { 316 Symbol location = sym.location(); 317 if (location.kind == MTH && 318 ((MethodSymbol)location).isStaticOrInstanceInit()) { 319 log.error(pos, "already.defined.in.clinit", kindName(sym), sym, 320 kindName(sym.location()), kindName(sym.location().enclClass()), 321 sym.location().enclClass()); 322 } else { 323 log.error(pos, "already.defined", kindName(sym), sym, 324 kindName(sym.location()), sym.location()); 325 } 326 } 327 } 328 329 /** Report array/varargs duplicate declaration 330 */ 331 void varargsDuplicateError(DiagnosticPosition pos, Symbol sym1, Symbol sym2) { 332 if (!sym1.type.isErroneous() && !sym2.type.isErroneous()) { 333 log.error(pos, "array.and.varargs", sym1, sym2, sym2.location()); 334 } 335 } 336 337/* ************************************************************************ 338 * duplicate declaration checking 339 *************************************************************************/ 340 341 /** Check that variable does not hide variable with same name in 342 * immediately enclosing local scope. 343 * @param pos Position for error reporting. 344 * @param v The symbol. 345 * @param s The scope. 346 */ 347 void checkTransparentVar(DiagnosticPosition pos, VarSymbol v, Scope s) { 348 for (Symbol sym : s.getSymbolsByName(v.name)) { 349 if (sym.owner != v.owner) break; 350 if (sym.kind == VAR && 351 sym.owner.kind.matches(KindSelector.VAL_MTH) && 352 v.name != names.error) { 353 duplicateError(pos, sym); 354 return; 355 } 356 } 357 } 358 359 /** Check that a class or interface does not hide a class or 360 * interface with same name in immediately enclosing local scope. 361 * @param pos Position for error reporting. 362 * @param c The symbol. 363 * @param s The scope. 364 */ 365 void checkTransparentClass(DiagnosticPosition pos, ClassSymbol c, Scope s) { 366 for (Symbol sym : s.getSymbolsByName(c.name)) { 367 if (sym.owner != c.owner) break; 368 if (sym.kind == TYP && !sym.type.hasTag(TYPEVAR) && 369 sym.owner.kind.matches(KindSelector.VAL_MTH) && 370 c.name != names.error) { 371 duplicateError(pos, sym); 372 return; 373 } 374 } 375 } 376 377 /** Check that class does not have the same name as one of 378 * its enclosing classes, or as a class defined in its enclosing scope. 379 * return true if class is unique in its enclosing scope. 380 * @param pos Position for error reporting. 381 * @param name The class name. 382 * @param s The enclosing scope. 383 */ 384 boolean checkUniqueClassName(DiagnosticPosition pos, Name name, Scope s) { 385 for (Symbol sym : s.getSymbolsByName(name, NON_RECURSIVE)) { 386 if (sym.kind == TYP && sym.name != names.error) { 387 duplicateError(pos, sym); 388 return false; 389 } 390 } 391 for (Symbol sym = s.owner; sym != null; sym = sym.owner) { 392 if (sym.kind == TYP && sym.name == name && sym.name != names.error) { 393 duplicateError(pos, sym); 394 return true; 395 } 396 } 397 return true; 398 } 399 400/* ************************************************************************* 401 * Class name generation 402 **************************************************************************/ 403 404 /** Return name of local class. 405 * This is of the form {@code <enclClass> $ n <classname> } 406 * where 407 * enclClass is the flat name of the enclosing class, 408 * classname is the simple name of the local class 409 */ 410 Name localClassName(ClassSymbol c) { 411 for (int i=1; ; i++) { 412 Name flatname = names. 413 fromString("" + c.owner.enclClass().flatname + 414 syntheticNameChar + i + 415 c.name); 416 if (compiled.get(flatname) == null) return flatname; 417 } 418 } 419 420 public void newRound() { 421 compiled.clear(); 422 } 423 424/* ************************************************************************* 425 * Type Checking 426 **************************************************************************/ 427 428 /** 429 * A check context is an object that can be used to perform compatibility 430 * checks - depending on the check context, meaning of 'compatibility' might 431 * vary significantly. 432 */ 433 public interface CheckContext { 434 /** 435 * Is type 'found' compatible with type 'req' in given context 436 */ 437 boolean compatible(Type found, Type req, Warner warn); 438 /** 439 * Report a check error 440 */ 441 void report(DiagnosticPosition pos, JCDiagnostic details); 442 /** 443 * Obtain a warner for this check context 444 */ 445 public Warner checkWarner(DiagnosticPosition pos, Type found, Type req); 446 447 public Infer.InferenceContext inferenceContext(); 448 449 public DeferredAttr.DeferredAttrContext deferredAttrContext(); 450 } 451 452 /** 453 * This class represent a check context that is nested within another check 454 * context - useful to check sub-expressions. The default behavior simply 455 * redirects all method calls to the enclosing check context leveraging 456 * the forwarding pattern. 457 */ 458 static class NestedCheckContext implements CheckContext { 459 CheckContext enclosingContext; 460 461 NestedCheckContext(CheckContext enclosingContext) { 462 this.enclosingContext = enclosingContext; 463 } 464 465 public boolean compatible(Type found, Type req, Warner warn) { 466 return enclosingContext.compatible(found, req, warn); 467 } 468 469 public void report(DiagnosticPosition pos, JCDiagnostic details) { 470 enclosingContext.report(pos, details); 471 } 472 473 public Warner checkWarner(DiagnosticPosition pos, Type found, Type req) { 474 return enclosingContext.checkWarner(pos, found, req); 475 } 476 477 public Infer.InferenceContext inferenceContext() { 478 return enclosingContext.inferenceContext(); 479 } 480 481 public DeferredAttrContext deferredAttrContext() { 482 return enclosingContext.deferredAttrContext(); 483 } 484 } 485 486 /** 487 * Check context to be used when evaluating assignment/return statements 488 */ 489 CheckContext basicHandler = new CheckContext() { 490 public void report(DiagnosticPosition pos, JCDiagnostic details) { 491 log.error(pos, "prob.found.req", details); 492 } 493 public boolean compatible(Type found, Type req, Warner warn) { 494 return types.isAssignable(found, req, warn); 495 } 496 497 public Warner checkWarner(DiagnosticPosition pos, Type found, Type req) { 498 return convertWarner(pos, found, req); 499 } 500 501 public InferenceContext inferenceContext() { 502 return infer.emptyContext; 503 } 504 505 public DeferredAttrContext deferredAttrContext() { 506 return deferredAttr.emptyDeferredAttrContext; 507 } 508 509 @Override 510 public String toString() { 511 return "CheckContext: basicHandler"; 512 } 513 }; 514 515 /** Check that a given type is assignable to a given proto-type. 516 * If it is, return the type, otherwise return errType. 517 * @param pos Position to be used for error reporting. 518 * @param found The type that was found. 519 * @param req The type that was required. 520 */ 521 Type checkType(DiagnosticPosition pos, Type found, Type req) { 522 return checkType(pos, found, req, basicHandler); 523 } 524 525 Type checkType(final DiagnosticPosition pos, final Type found, final Type req, final CheckContext checkContext) { 526 final Infer.InferenceContext inferenceContext = checkContext.inferenceContext(); 527 if (inferenceContext.free(req) || inferenceContext.free(found)) { 528 inferenceContext.addFreeTypeListener(List.of(req, found), new FreeTypeListener() { 529 @Override 530 public void typesInferred(InferenceContext inferenceContext) { 531 checkType(pos, inferenceContext.asInstType(found), inferenceContext.asInstType(req), checkContext); 532 } 533 }); 534 } 535 if (req.hasTag(ERROR)) 536 return req; 537 if (req.hasTag(NONE)) 538 return found; 539 if (checkContext.compatible(found, req, checkContext.checkWarner(pos, found, req))) { 540 return found; 541 } else { 542 if (found.isNumeric() && req.isNumeric()) { 543 checkContext.report(pos, diags.fragment("possible.loss.of.precision", found, req)); 544 return types.createErrorType(found); 545 } 546 checkContext.report(pos, diags.fragment("inconvertible.types", found, req)); 547 return types.createErrorType(found); 548 } 549 } 550 551 /** Check that a given type can be cast to a given target type. 552 * Return the result of the cast. 553 * @param pos Position to be used for error reporting. 554 * @param found The type that is being cast. 555 * @param req The target type of the cast. 556 */ 557 Type checkCastable(DiagnosticPosition pos, Type found, Type req) { 558 return checkCastable(pos, found, req, basicHandler); 559 } 560 Type checkCastable(DiagnosticPosition pos, Type found, Type req, CheckContext checkContext) { 561 if (types.isCastable(found, req, castWarner(pos, found, req))) { 562 return req; 563 } else { 564 checkContext.report(pos, diags.fragment("inconvertible.types", found, req)); 565 return types.createErrorType(found); 566 } 567 } 568 569 /** Check for redundant casts (i.e. where source type is a subtype of target type) 570 * The problem should only be reported for non-292 cast 571 */ 572 public void checkRedundantCast(Env<AttrContext> env, final JCTypeCast tree) { 573 if (!tree.type.isErroneous() 574 && types.isSameType(tree.expr.type, tree.clazz.type) 575 && !(ignoreAnnotatedCasts && TreeInfo.containsTypeAnnotation(tree.clazz)) 576 && !is292targetTypeCast(tree)) { 577 deferredLintHandler.report(new DeferredLintHandler.LintLogger() { 578 @Override 579 public void report() { 580 if (lint.isEnabled(Lint.LintCategory.CAST)) 581 log.warning(Lint.LintCategory.CAST, 582 tree.pos(), "redundant.cast", tree.expr.type); 583 } 584 }); 585 } 586 } 587 //where 588 private boolean is292targetTypeCast(JCTypeCast tree) { 589 boolean is292targetTypeCast = false; 590 JCExpression expr = TreeInfo.skipParens(tree.expr); 591 if (expr.hasTag(APPLY)) { 592 JCMethodInvocation apply = (JCMethodInvocation)expr; 593 Symbol sym = TreeInfo.symbol(apply.meth); 594 is292targetTypeCast = sym != null && 595 sym.kind == MTH && 596 (sym.flags() & HYPOTHETICAL) != 0; 597 } 598 return is292targetTypeCast; 599 } 600 601 private static final boolean ignoreAnnotatedCasts = true; 602 603 /** Check that a type is within some bounds. 604 * 605 * Used in TypeApply to verify that, e.g., X in {@code V<X>} is a valid 606 * type argument. 607 * @param a The type that should be bounded by bs. 608 * @param bound The bound. 609 */ 610 private boolean checkExtends(Type a, Type bound) { 611 if (a.isUnbound()) { 612 return true; 613 } else if (!a.hasTag(WILDCARD)) { 614 a = types.cvarUpperBound(a); 615 return types.isSubtype(a, bound); 616 } else if (a.isExtendsBound()) { 617 return types.isCastable(bound, types.wildUpperBound(a), types.noWarnings); 618 } else if (a.isSuperBound()) { 619 return !types.notSoftSubtype(types.wildLowerBound(a), bound); 620 } 621 return true; 622 } 623 624 /** Check that type is different from 'void'. 625 * @param pos Position to be used for error reporting. 626 * @param t The type to be checked. 627 */ 628 Type checkNonVoid(DiagnosticPosition pos, Type t) { 629 if (t.hasTag(VOID)) { 630 log.error(pos, "void.not.allowed.here"); 631 return types.createErrorType(t); 632 } else { 633 return t; 634 } 635 } 636 637 Type checkClassOrArrayType(DiagnosticPosition pos, Type t) { 638 if (!t.hasTag(CLASS) && !t.hasTag(ARRAY) && !t.hasTag(ERROR)) { 639 return typeTagError(pos, 640 diags.fragment("type.req.class.array"), 641 asTypeParam(t)); 642 } else { 643 return t; 644 } 645 } 646 647 /** Check that type is a class or interface type. 648 * @param pos Position to be used for error reporting. 649 * @param t The type to be checked. 650 */ 651 Type checkClassType(DiagnosticPosition pos, Type t) { 652 if (!t.hasTag(CLASS) && !t.hasTag(ERROR)) { 653 return typeTagError(pos, 654 diags.fragment("type.req.class"), 655 asTypeParam(t)); 656 } else { 657 return t; 658 } 659 } 660 //where 661 private Object asTypeParam(Type t) { 662 return (t.hasTag(TYPEVAR)) 663 ? diags.fragment("type.parameter", t) 664 : t; 665 } 666 667 /** Check that type is a valid qualifier for a constructor reference expression 668 */ 669 Type checkConstructorRefType(DiagnosticPosition pos, Type t) { 670 t = checkClassOrArrayType(pos, t); 671 if (t.hasTag(CLASS)) { 672 if ((t.tsym.flags() & (ABSTRACT | INTERFACE)) != 0) { 673 log.error(pos, "abstract.cant.be.instantiated", t.tsym); 674 t = types.createErrorType(t); 675 } else if ((t.tsym.flags() & ENUM) != 0) { 676 log.error(pos, "enum.cant.be.instantiated"); 677 t = types.createErrorType(t); 678 } else { 679 t = checkClassType(pos, t, true); 680 } 681 } else if (t.hasTag(ARRAY)) { 682 if (!types.isReifiable(((ArrayType)t).elemtype)) { 683 log.error(pos, "generic.array.creation"); 684 t = types.createErrorType(t); 685 } 686 } 687 return t; 688 } 689 690 /** Check that type is a class or interface type. 691 * @param pos Position to be used for error reporting. 692 * @param t The type to be checked. 693 * @param noBounds True if type bounds are illegal here. 694 */ 695 Type checkClassType(DiagnosticPosition pos, Type t, boolean noBounds) { 696 t = checkClassType(pos, t); 697 if (noBounds && t.isParameterized()) { 698 List<Type> args = t.getTypeArguments(); 699 while (args.nonEmpty()) { 700 if (args.head.hasTag(WILDCARD)) 701 return typeTagError(pos, 702 diags.fragment("type.req.exact"), 703 args.head); 704 args = args.tail; 705 } 706 } 707 return t; 708 } 709 710 /** Check that type is a reference type, i.e. a class, interface or array type 711 * or a type variable. 712 * @param pos Position to be used for error reporting. 713 * @param t The type to be checked. 714 */ 715 Type checkRefType(DiagnosticPosition pos, Type t) { 716 if (t.isReference()) 717 return t; 718 else 719 return typeTagError(pos, 720 diags.fragment("type.req.ref"), 721 t); 722 } 723 724 /** Check that each type is a reference type, i.e. a class, interface or array type 725 * or a type variable. 726 * @param trees Original trees, used for error reporting. 727 * @param types The types to be checked. 728 */ 729 List<Type> checkRefTypes(List<JCExpression> trees, List<Type> types) { 730 List<JCExpression> tl = trees; 731 for (List<Type> l = types; l.nonEmpty(); l = l.tail) { 732 l.head = checkRefType(tl.head.pos(), l.head); 733 tl = tl.tail; 734 } 735 return types; 736 } 737 738 /** Check that type is a null or reference type. 739 * @param pos Position to be used for error reporting. 740 * @param t The type to be checked. 741 */ 742 Type checkNullOrRefType(DiagnosticPosition pos, Type t) { 743 if (t.isReference() || t.hasTag(BOT)) 744 return t; 745 else 746 return typeTagError(pos, 747 diags.fragment("type.req.ref"), 748 t); 749 } 750 751 /** Check that flag set does not contain elements of two conflicting sets. s 752 * Return true if it doesn't. 753 * @param pos Position to be used for error reporting. 754 * @param flags The set of flags to be checked. 755 * @param set1 Conflicting flags set #1. 756 * @param set2 Conflicting flags set #2. 757 */ 758 boolean checkDisjoint(DiagnosticPosition pos, long flags, long set1, long set2) { 759 if ((flags & set1) != 0 && (flags & set2) != 0) { 760 log.error(pos, 761 "illegal.combination.of.modifiers", 762 asFlagSet(TreeInfo.firstFlag(flags & set1)), 763 asFlagSet(TreeInfo.firstFlag(flags & set2))); 764 return false; 765 } else 766 return true; 767 } 768 769 /** Check that usage of diamond operator is correct (i.e. diamond should not 770 * be used with non-generic classes or in anonymous class creation expressions) 771 */ 772 Type checkDiamond(JCNewClass tree, Type t) { 773 if (!TreeInfo.isDiamond(tree) || 774 t.isErroneous()) { 775 return checkClassType(tree.clazz.pos(), t, true); 776 } else if (tree.def != null) { 777 log.error(tree.clazz.pos(), 778 "cant.apply.diamond.1", 779 t, diags.fragment("diamond.and.anon.class", t)); 780 return types.createErrorType(t); 781 } else if (t.tsym.type.getTypeArguments().isEmpty()) { 782 log.error(tree.clazz.pos(), 783 "cant.apply.diamond.1", 784 t, diags.fragment("diamond.non.generic", t)); 785 return types.createErrorType(t); 786 } else if (tree.typeargs != null && 787 tree.typeargs.nonEmpty()) { 788 log.error(tree.clazz.pos(), 789 "cant.apply.diamond.1", 790 t, diags.fragment("diamond.and.explicit.params", t)); 791 return types.createErrorType(t); 792 } else { 793 return t; 794 } 795 } 796 797 void checkVarargsMethodDecl(Env<AttrContext> env, JCMethodDecl tree) { 798 MethodSymbol m = tree.sym; 799 if (!allowSimplifiedVarargs) return; 800 boolean hasTrustMeAnno = m.attribute(syms.trustMeType.tsym) != null; 801 Type varargElemType = null; 802 if (m.isVarArgs()) { 803 varargElemType = types.elemtype(tree.params.last().type); 804 } 805 if (hasTrustMeAnno && !isTrustMeAllowedOnMethod(m)) { 806 if (varargElemType != null) { 807 log.error(tree, 808 "varargs.invalid.trustme.anno", 809 syms.trustMeType.tsym, 810 allowPrivateSafeVarargs ? 811 diags.fragment("varargs.trustme.on.virtual.varargs", m) : 812 diags.fragment("varargs.trustme.on.virtual.varargs.final.only", m)); 813 } else { 814 log.error(tree, 815 "varargs.invalid.trustme.anno", 816 syms.trustMeType.tsym, 817 diags.fragment("varargs.trustme.on.non.varargs.meth", m)); 818 } 819 } else if (hasTrustMeAnno && varargElemType != null && 820 types.isReifiable(varargElemType)) { 821 warnUnsafeVararg(tree, 822 "varargs.redundant.trustme.anno", 823 syms.trustMeType.tsym, 824 diags.fragment("varargs.trustme.on.reifiable.varargs", varargElemType)); 825 } 826 else if (!hasTrustMeAnno && varargElemType != null && 827 !types.isReifiable(varargElemType)) { 828 warnUnchecked(tree.params.head.pos(), "unchecked.varargs.non.reifiable.type", varargElemType); 829 } 830 } 831 //where 832 private boolean isTrustMeAllowedOnMethod(Symbol s) { 833 return (s.flags() & VARARGS) != 0 && 834 (s.isConstructor() || 835 (s.flags() & (STATIC | FINAL | 836 (allowPrivateSafeVarargs ? PRIVATE : 0) )) != 0); 837 } 838 839 Type checkMethod(final Type mtype, 840 final Symbol sym, 841 final Env<AttrContext> env, 842 final List<JCExpression> argtrees, 843 final List<Type> argtypes, 844 final boolean useVarargs, 845 InferenceContext inferenceContext) { 846 // System.out.println("call : " + env.tree); 847 // System.out.println("method : " + owntype); 848 // System.out.println("actuals: " + argtypes); 849 if (inferenceContext.free(mtype)) { 850 inferenceContext.addFreeTypeListener(List.of(mtype), new FreeTypeListener() { 851 public void typesInferred(InferenceContext inferenceContext) { 852 checkMethod(inferenceContext.asInstType(mtype), sym, env, argtrees, argtypes, useVarargs, inferenceContext); 853 } 854 }); 855 return mtype; 856 } 857 Type owntype = mtype; 858 List<Type> formals = owntype.getParameterTypes(); 859 List<Type> nonInferred = sym.type.getParameterTypes(); 860 if (nonInferred.length() != formals.length()) nonInferred = formals; 861 Type last = useVarargs ? formals.last() : null; 862 if (sym.name == names.init && sym.owner == syms.enumSym) { 863 formals = formals.tail.tail; 864 nonInferred = nonInferred.tail.tail; 865 } 866 List<JCExpression> args = argtrees; 867 if (args != null) { 868 //this is null when type-checking a method reference 869 while (formals.head != last) { 870 JCTree arg = args.head; 871 Warner warn = convertWarner(arg.pos(), arg.type, nonInferred.head); 872 assertConvertible(arg, arg.type, formals.head, warn); 873 args = args.tail; 874 formals = formals.tail; 875 nonInferred = nonInferred.tail; 876 } 877 if (useVarargs) { 878 Type varArg = types.elemtype(last); 879 while (args.tail != null) { 880 JCTree arg = args.head; 881 Warner warn = convertWarner(arg.pos(), arg.type, varArg); 882 assertConvertible(arg, arg.type, varArg, warn); 883 args = args.tail; 884 } 885 } else if ((sym.flags() & (VARARGS | SIGNATURE_POLYMORPHIC)) == VARARGS) { 886 // non-varargs call to varargs method 887 Type varParam = owntype.getParameterTypes().last(); 888 Type lastArg = argtypes.last(); 889 if (types.isSubtypeUnchecked(lastArg, types.elemtype(varParam)) && 890 !types.isSameType(types.erasure(varParam), types.erasure(lastArg))) 891 log.warning(argtrees.last().pos(), "inexact.non-varargs.call", 892 types.elemtype(varParam), varParam); 893 } 894 } 895 if (useVarargs) { 896 Type argtype = owntype.getParameterTypes().last(); 897 if (!types.isReifiable(argtype) && 898 (!allowSimplifiedVarargs || 899 sym.baseSymbol().attribute(syms.trustMeType.tsym) == null || 900 !isTrustMeAllowedOnMethod(sym))) { 901 warnUnchecked(env.tree.pos(), 902 "unchecked.generic.array.creation", 903 argtype); 904 } 905 if ((sym.baseSymbol().flags() & SIGNATURE_POLYMORPHIC) == 0) { 906 TreeInfo.setVarargsElement(env.tree, types.elemtype(argtype)); 907 } 908 } 909 PolyKind pkind = (sym.type.hasTag(FORALL) && 910 sym.type.getReturnType().containsAny(((ForAll)sym.type).tvars)) ? 911 PolyKind.POLY : PolyKind.STANDALONE; 912 TreeInfo.setPolyKind(env.tree, pkind); 913 return owntype; 914 } 915 //where 916 private void assertConvertible(JCTree tree, Type actual, Type formal, Warner warn) { 917 if (types.isConvertible(actual, formal, warn)) 918 return; 919 920 if (formal.isCompound() 921 && types.isSubtype(actual, types.supertype(formal)) 922 && types.isSubtypeUnchecked(actual, types.interfaces(formal), warn)) 923 return; 924 } 925 926 /** 927 * Check that type 't' is a valid instantiation of a generic class 928 * (see JLS 4.5) 929 * 930 * @param t class type to be checked 931 * @return true if 't' is well-formed 932 */ 933 public boolean checkValidGenericType(Type t) { 934 return firstIncompatibleTypeArg(t) == null; 935 } 936 //WHERE 937 private Type firstIncompatibleTypeArg(Type type) { 938 List<Type> formals = type.tsym.type.allparams(); 939 List<Type> actuals = type.allparams(); 940 List<Type> args = type.getTypeArguments(); 941 List<Type> forms = type.tsym.type.getTypeArguments(); 942 ListBuffer<Type> bounds_buf = new ListBuffer<>(); 943 944 // For matching pairs of actual argument types `a' and 945 // formal type parameters with declared bound `b' ... 946 while (args.nonEmpty() && forms.nonEmpty()) { 947 // exact type arguments needs to know their 948 // bounds (for upper and lower bound 949 // calculations). So we create new bounds where 950 // type-parameters are replaced with actuals argument types. 951 bounds_buf.append(types.subst(forms.head.getUpperBound(), formals, actuals)); 952 args = args.tail; 953 forms = forms.tail; 954 } 955 956 args = type.getTypeArguments(); 957 List<Type> tvars_cap = types.substBounds(formals, 958 formals, 959 types.capture(type).allparams()); 960 while (args.nonEmpty() && tvars_cap.nonEmpty()) { 961 // Let the actual arguments know their bound 962 args.head.withTypeVar((TypeVar)tvars_cap.head); 963 args = args.tail; 964 tvars_cap = tvars_cap.tail; 965 } 966 967 args = type.getTypeArguments(); 968 List<Type> bounds = bounds_buf.toList(); 969 970 while (args.nonEmpty() && bounds.nonEmpty()) { 971 Type actual = args.head; 972 if (!isTypeArgErroneous(actual) && 973 !bounds.head.isErroneous() && 974 !checkExtends(actual, bounds.head)) { 975 return args.head; 976 } 977 args = args.tail; 978 bounds = bounds.tail; 979 } 980 981 args = type.getTypeArguments(); 982 bounds = bounds_buf.toList(); 983 984 for (Type arg : types.capture(type).getTypeArguments()) { 985 if (arg.hasTag(TYPEVAR) && 986 arg.getUpperBound().isErroneous() && 987 !bounds.head.isErroneous() && 988 !isTypeArgErroneous(args.head)) { 989 return args.head; 990 } 991 bounds = bounds.tail; 992 args = args.tail; 993 } 994 995 return null; 996 } 997 //where 998 boolean isTypeArgErroneous(Type t) { 999 return isTypeArgErroneous.visit(t); 1000 } 1001 1002 Types.UnaryVisitor<Boolean> isTypeArgErroneous = new Types.UnaryVisitor<Boolean>() { 1003 public Boolean visitType(Type t, Void s) { 1004 return t.isErroneous(); 1005 } 1006 @Override 1007 public Boolean visitTypeVar(TypeVar t, Void s) { 1008 return visit(t.getUpperBound()); 1009 } 1010 @Override 1011 public Boolean visitCapturedType(CapturedType t, Void s) { 1012 return visit(t.getUpperBound()) || 1013 visit(t.getLowerBound()); 1014 } 1015 @Override 1016 public Boolean visitWildcardType(WildcardType t, Void s) { 1017 return visit(t.type); 1018 } 1019 }; 1020 1021 /** Check that given modifiers are legal for given symbol and 1022 * return modifiers together with any implicit modifiers for that symbol. 1023 * Warning: we can't use flags() here since this method 1024 * is called during class enter, when flags() would cause a premature 1025 * completion. 1026 * @param pos Position to be used for error reporting. 1027 * @param flags The set of modifiers given in a definition. 1028 * @param sym The defined symbol. 1029 */ 1030 long checkFlags(DiagnosticPosition pos, long flags, Symbol sym, JCTree tree) { 1031 long mask; 1032 long implicit = 0; 1033 1034 switch (sym.kind) { 1035 case VAR: 1036 if (TreeInfo.isReceiverParam(tree)) 1037 mask = ReceiverParamFlags; 1038 else if (sym.owner.kind != TYP) 1039 mask = LocalVarFlags; 1040 else if ((sym.owner.flags_field & INTERFACE) != 0) 1041 mask = implicit = InterfaceVarFlags; 1042 else 1043 mask = VarFlags; 1044 break; 1045 case MTH: 1046 if (sym.name == names.init) { 1047 if ((sym.owner.flags_field & ENUM) != 0) { 1048 // enum constructors cannot be declared public or 1049 // protected and must be implicitly or explicitly 1050 // private 1051 implicit = PRIVATE; 1052 mask = PRIVATE; 1053 } else 1054 mask = ConstructorFlags; 1055 } else if ((sym.owner.flags_field & INTERFACE) != 0) { 1056 if ((sym.owner.flags_field & ANNOTATION) != 0) { 1057 mask = AnnotationTypeElementMask; 1058 implicit = PUBLIC | ABSTRACT; 1059 } else if ((flags & (DEFAULT | STATIC)) != 0) { 1060 mask = InterfaceMethodMask; 1061 implicit = PUBLIC; 1062 if ((flags & DEFAULT) != 0) { 1063 implicit |= ABSTRACT; 1064 } 1065 } else { 1066 mask = implicit = InterfaceMethodFlags; 1067 } 1068 } else { 1069 mask = MethodFlags; 1070 } 1071 // Imply STRICTFP if owner has STRICTFP set. 1072 if (((flags|implicit) & Flags.ABSTRACT) == 0 || 1073 ((flags) & Flags.DEFAULT) != 0) 1074 implicit |= sym.owner.flags_field & STRICTFP; 1075 break; 1076 case TYP: 1077 if (sym.isLocal()) { 1078 mask = LocalClassFlags; 1079 if (sym.name.isEmpty()) { // Anonymous class 1080 // JLS: Anonymous classes are final. 1081 implicit |= FINAL; 1082 } 1083 if ((sym.owner.flags_field & STATIC) == 0 && 1084 (flags & ENUM) != 0) 1085 log.error(pos, "enums.must.be.static"); 1086 } else if (sym.owner.kind == TYP) { 1087 mask = MemberClassFlags; 1088 if (sym.owner.owner.kind == PCK || 1089 (sym.owner.flags_field & STATIC) != 0) 1090 mask |= STATIC; 1091 else if ((flags & ENUM) != 0) 1092 log.error(pos, "enums.must.be.static"); 1093 // Nested interfaces and enums are always STATIC (Spec ???) 1094 if ((flags & (INTERFACE | ENUM)) != 0 ) implicit = STATIC; 1095 } else { 1096 mask = ClassFlags; 1097 } 1098 // Interfaces are always ABSTRACT 1099 if ((flags & INTERFACE) != 0) implicit |= ABSTRACT; 1100 1101 if ((flags & ENUM) != 0) { 1102 // enums can't be declared abstract or final 1103 mask &= ~(ABSTRACT | FINAL); 1104 implicit |= implicitEnumFinalFlag(tree); 1105 } 1106 // Imply STRICTFP if owner has STRICTFP set. 1107 implicit |= sym.owner.flags_field & STRICTFP; 1108 break; 1109 default: 1110 throw new AssertionError(); 1111 } 1112 long illegal = flags & ExtendedStandardFlags & ~mask; 1113 if (illegal != 0) { 1114 if ((illegal & INTERFACE) != 0) { 1115 log.error(pos, "intf.not.allowed.here"); 1116 mask |= INTERFACE; 1117 } 1118 else { 1119 log.error(pos, 1120 "mod.not.allowed.here", asFlagSet(illegal)); 1121 } 1122 } 1123 else if ((sym.kind == TYP || 1124 // ISSUE: Disallowing abstract&private is no longer appropriate 1125 // in the presence of inner classes. Should it be deleted here? 1126 checkDisjoint(pos, flags, 1127 ABSTRACT, 1128 PRIVATE | STATIC | DEFAULT)) 1129 && 1130 checkDisjoint(pos, flags, 1131 STATIC, 1132 DEFAULT) 1133 && 1134 checkDisjoint(pos, flags, 1135 ABSTRACT | INTERFACE, 1136 FINAL | NATIVE | SYNCHRONIZED) 1137 && 1138 checkDisjoint(pos, flags, 1139 PUBLIC, 1140 PRIVATE | PROTECTED) 1141 && 1142 checkDisjoint(pos, flags, 1143 PRIVATE, 1144 PUBLIC | PROTECTED) 1145 && 1146 checkDisjoint(pos, flags, 1147 FINAL, 1148 VOLATILE) 1149 && 1150 (sym.kind == TYP || 1151 checkDisjoint(pos, flags, 1152 ABSTRACT | NATIVE, 1153 STRICTFP))) { 1154 // skip 1155 } 1156 return flags & (mask | ~ExtendedStandardFlags) | implicit; 1157 } 1158 1159 1160 /** Determine if this enum should be implicitly final. 1161 * 1162 * If the enum has no specialized enum contants, it is final. 1163 * 1164 * If the enum does have specialized enum contants, it is 1165 * <i>not</i> final. 1166 */ 1167 private long implicitEnumFinalFlag(JCTree tree) { 1168 if (!tree.hasTag(CLASSDEF)) return 0; 1169 class SpecialTreeVisitor extends JCTree.Visitor { 1170 boolean specialized; 1171 SpecialTreeVisitor() { 1172 this.specialized = false; 1173 } 1174 1175 @Override 1176 public void visitTree(JCTree tree) { /* no-op */ } 1177 1178 @Override 1179 public void visitVarDef(JCVariableDecl tree) { 1180 if ((tree.mods.flags & ENUM) != 0) { 1181 if (tree.init instanceof JCNewClass && 1182 ((JCNewClass) tree.init).def != null) { 1183 specialized = true; 1184 } 1185 } 1186 } 1187 } 1188 1189 SpecialTreeVisitor sts = new SpecialTreeVisitor(); 1190 JCClassDecl cdef = (JCClassDecl) tree; 1191 for (JCTree defs: cdef.defs) { 1192 defs.accept(sts); 1193 if (sts.specialized) return 0; 1194 } 1195 return FINAL; 1196 } 1197 1198/* ************************************************************************* 1199 * Type Validation 1200 **************************************************************************/ 1201 1202 /** Validate a type expression. That is, 1203 * check that all type arguments of a parametric type are within 1204 * their bounds. This must be done in a second phase after type attribution 1205 * since a class might have a subclass as type parameter bound. E.g: 1206 * 1207 * <pre>{@code 1208 * class B<A extends C> { ... } 1209 * class C extends B<C> { ... } 1210 * }</pre> 1211 * 1212 * and we can't make sure that the bound is already attributed because 1213 * of possible cycles. 1214 * 1215 * Visitor method: Validate a type expression, if it is not null, catching 1216 * and reporting any completion failures. 1217 */ 1218 void validate(JCTree tree, Env<AttrContext> env) { 1219 validate(tree, env, true); 1220 } 1221 void validate(JCTree tree, Env<AttrContext> env, boolean checkRaw) { 1222 new Validator(env).validateTree(tree, checkRaw, true); 1223 } 1224 1225 /** Visitor method: Validate a list of type expressions. 1226 */ 1227 void validate(List<? extends JCTree> trees, Env<AttrContext> env) { 1228 for (List<? extends JCTree> l = trees; l.nonEmpty(); l = l.tail) 1229 validate(l.head, env); 1230 } 1231 1232 /** A visitor class for type validation. 1233 */ 1234 class Validator extends JCTree.Visitor { 1235 1236 boolean checkRaw; 1237 boolean isOuter; 1238 Env<AttrContext> env; 1239 1240 Validator(Env<AttrContext> env) { 1241 this.env = env; 1242 } 1243 1244 @Override 1245 public void visitTypeArray(JCArrayTypeTree tree) { 1246 validateTree(tree.elemtype, checkRaw, isOuter); 1247 } 1248 1249 @Override 1250 public void visitTypeApply(JCTypeApply tree) { 1251 if (tree.type.hasTag(CLASS)) { 1252 List<JCExpression> args = tree.arguments; 1253 List<Type> forms = tree.type.tsym.type.getTypeArguments(); 1254 1255 Type incompatibleArg = firstIncompatibleTypeArg(tree.type); 1256 if (incompatibleArg != null) { 1257 for (JCTree arg : tree.arguments) { 1258 if (arg.type == incompatibleArg) { 1259 log.error(arg, "not.within.bounds", incompatibleArg, forms.head); 1260 } 1261 forms = forms.tail; 1262 } 1263 } 1264 1265 forms = tree.type.tsym.type.getTypeArguments(); 1266 1267 boolean is_java_lang_Class = tree.type.tsym.flatName() == names.java_lang_Class; 1268 1269 // For matching pairs of actual argument types `a' and 1270 // formal type parameters with declared bound `b' ... 1271 while (args.nonEmpty() && forms.nonEmpty()) { 1272 validateTree(args.head, 1273 !(isOuter && is_java_lang_Class), 1274 false); 1275 args = args.tail; 1276 forms = forms.tail; 1277 } 1278 1279 // Check that this type is either fully parameterized, or 1280 // not parameterized at all. 1281 if (tree.type.getEnclosingType().isRaw()) 1282 log.error(tree.pos(), "improperly.formed.type.inner.raw.param"); 1283 if (tree.clazz.hasTag(SELECT)) 1284 visitSelectInternal((JCFieldAccess)tree.clazz); 1285 } 1286 } 1287 1288 @Override 1289 public void visitTypeParameter(JCTypeParameter tree) { 1290 validateTrees(tree.bounds, true, isOuter); 1291 checkClassBounds(tree.pos(), tree.type); 1292 } 1293 1294 @Override 1295 public void visitWildcard(JCWildcard tree) { 1296 if (tree.inner != null) 1297 validateTree(tree.inner, true, isOuter); 1298 } 1299 1300 @Override 1301 public void visitSelect(JCFieldAccess tree) { 1302 if (tree.type.hasTag(CLASS)) { 1303 visitSelectInternal(tree); 1304 1305 // Check that this type is either fully parameterized, or 1306 // not parameterized at all. 1307 if (tree.selected.type.isParameterized() && tree.type.tsym.type.getTypeArguments().nonEmpty()) 1308 log.error(tree.pos(), "improperly.formed.type.param.missing"); 1309 } 1310 } 1311 1312 public void visitSelectInternal(JCFieldAccess tree) { 1313 if (tree.type.tsym.isStatic() && 1314 tree.selected.type.isParameterized()) { 1315 // The enclosing type is not a class, so we are 1316 // looking at a static member type. However, the 1317 // qualifying expression is parameterized. 1318 log.error(tree.pos(), "cant.select.static.class.from.param.type"); 1319 } else { 1320 // otherwise validate the rest of the expression 1321 tree.selected.accept(this); 1322 } 1323 } 1324 1325 @Override 1326 public void visitAnnotatedType(JCAnnotatedType tree) { 1327 tree.underlyingType.accept(this); 1328 } 1329 1330 @Override 1331 public void visitTypeIdent(JCPrimitiveTypeTree that) { 1332 if (that.type.hasTag(TypeTag.VOID)) { 1333 log.error(that.pos(), "void.not.allowed.here"); 1334 } 1335 super.visitTypeIdent(that); 1336 } 1337 1338 /** Default visitor method: do nothing. 1339 */ 1340 @Override 1341 public void visitTree(JCTree tree) { 1342 } 1343 1344 public void validateTree(JCTree tree, boolean checkRaw, boolean isOuter) { 1345 if (tree != null) { 1346 boolean prevCheckRaw = this.checkRaw; 1347 this.checkRaw = checkRaw; 1348 this.isOuter = isOuter; 1349 1350 try { 1351 tree.accept(this); 1352 if (checkRaw) 1353 checkRaw(tree, env); 1354 } catch (CompletionFailure ex) { 1355 completionError(tree.pos(), ex); 1356 } finally { 1357 this.checkRaw = prevCheckRaw; 1358 } 1359 } 1360 } 1361 1362 public void validateTrees(List<? extends JCTree> trees, boolean checkRaw, boolean isOuter) { 1363 for (List<? extends JCTree> l = trees; l.nonEmpty(); l = l.tail) 1364 validateTree(l.head, checkRaw, isOuter); 1365 } 1366 } 1367 1368 void checkRaw(JCTree tree, Env<AttrContext> env) { 1369 if (lint.isEnabled(LintCategory.RAW) && 1370 tree.type.hasTag(CLASS) && 1371 !TreeInfo.isDiamond(tree) && 1372 !withinAnonConstr(env) && 1373 tree.type.isRaw()) { 1374 log.warning(LintCategory.RAW, 1375 tree.pos(), "raw.class.use", tree.type, tree.type.tsym.type); 1376 } 1377 } 1378 //where 1379 private boolean withinAnonConstr(Env<AttrContext> env) { 1380 return env.enclClass.name.isEmpty() && 1381 env.enclMethod != null && env.enclMethod.name == names.init; 1382 } 1383 1384/* ************************************************************************* 1385 * Exception checking 1386 **************************************************************************/ 1387 1388 /* The following methods treat classes as sets that contain 1389 * the class itself and all their subclasses 1390 */ 1391 1392 /** Is given type a subtype of some of the types in given list? 1393 */ 1394 boolean subset(Type t, List<Type> ts) { 1395 for (List<Type> l = ts; l.nonEmpty(); l = l.tail) 1396 if (types.isSubtype(t, l.head)) return true; 1397 return false; 1398 } 1399 1400 /** Is given type a subtype or supertype of 1401 * some of the types in given list? 1402 */ 1403 boolean intersects(Type t, List<Type> ts) { 1404 for (List<Type> l = ts; l.nonEmpty(); l = l.tail) 1405 if (types.isSubtype(t, l.head) || types.isSubtype(l.head, t)) return true; 1406 return false; 1407 } 1408 1409 /** Add type set to given type list, unless it is a subclass of some class 1410 * in the list. 1411 */ 1412 List<Type> incl(Type t, List<Type> ts) { 1413 return subset(t, ts) ? ts : excl(t, ts).prepend(t); 1414 } 1415 1416 /** Remove type set from type set list. 1417 */ 1418 List<Type> excl(Type t, List<Type> ts) { 1419 if (ts.isEmpty()) { 1420 return ts; 1421 } else { 1422 List<Type> ts1 = excl(t, ts.tail); 1423 if (types.isSubtype(ts.head, t)) return ts1; 1424 else if (ts1 == ts.tail) return ts; 1425 else return ts1.prepend(ts.head); 1426 } 1427 } 1428 1429 /** Form the union of two type set lists. 1430 */ 1431 List<Type> union(List<Type> ts1, List<Type> ts2) { 1432 List<Type> ts = ts1; 1433 for (List<Type> l = ts2; l.nonEmpty(); l = l.tail) 1434 ts = incl(l.head, ts); 1435 return ts; 1436 } 1437 1438 /** Form the difference of two type lists. 1439 */ 1440 List<Type> diff(List<Type> ts1, List<Type> ts2) { 1441 List<Type> ts = ts1; 1442 for (List<Type> l = ts2; l.nonEmpty(); l = l.tail) 1443 ts = excl(l.head, ts); 1444 return ts; 1445 } 1446 1447 /** Form the intersection of two type lists. 1448 */ 1449 public List<Type> intersect(List<Type> ts1, List<Type> ts2) { 1450 List<Type> ts = List.nil(); 1451 for (List<Type> l = ts1; l.nonEmpty(); l = l.tail) 1452 if (subset(l.head, ts2)) ts = incl(l.head, ts); 1453 for (List<Type> l = ts2; l.nonEmpty(); l = l.tail) 1454 if (subset(l.head, ts1)) ts = incl(l.head, ts); 1455 return ts; 1456 } 1457 1458 /** Is exc an exception symbol that need not be declared? 1459 */ 1460 boolean isUnchecked(ClassSymbol exc) { 1461 return 1462 exc.kind == ERR || 1463 exc.isSubClass(syms.errorType.tsym, types) || 1464 exc.isSubClass(syms.runtimeExceptionType.tsym, types); 1465 } 1466 1467 /** Is exc an exception type that need not be declared? 1468 */ 1469 boolean isUnchecked(Type exc) { 1470 return 1471 (exc.hasTag(TYPEVAR)) ? isUnchecked(types.supertype(exc)) : 1472 (exc.hasTag(CLASS)) ? isUnchecked((ClassSymbol)exc.tsym) : 1473 exc.hasTag(BOT); 1474 } 1475 1476 /** Same, but handling completion failures. 1477 */ 1478 boolean isUnchecked(DiagnosticPosition pos, Type exc) { 1479 try { 1480 return isUnchecked(exc); 1481 } catch (CompletionFailure ex) { 1482 completionError(pos, ex); 1483 return true; 1484 } 1485 } 1486 1487 /** Is exc handled by given exception list? 1488 */ 1489 boolean isHandled(Type exc, List<Type> handled) { 1490 return isUnchecked(exc) || subset(exc, handled); 1491 } 1492 1493 /** Return all exceptions in thrown list that are not in handled list. 1494 * @param thrown The list of thrown exceptions. 1495 * @param handled The list of handled exceptions. 1496 */ 1497 List<Type> unhandled(List<Type> thrown, List<Type> handled) { 1498 List<Type> unhandled = List.nil(); 1499 for (List<Type> l = thrown; l.nonEmpty(); l = l.tail) 1500 if (!isHandled(l.head, handled)) unhandled = unhandled.prepend(l.head); 1501 return unhandled; 1502 } 1503 1504/* ************************************************************************* 1505 * Overriding/Implementation checking 1506 **************************************************************************/ 1507 1508 /** The level of access protection given by a flag set, 1509 * where PRIVATE is highest and PUBLIC is lowest. 1510 */ 1511 static int protection(long flags) { 1512 switch ((short)(flags & AccessFlags)) { 1513 case PRIVATE: return 3; 1514 case PROTECTED: return 1; 1515 default: 1516 case PUBLIC: return 0; 1517 case 0: return 2; 1518 } 1519 } 1520 1521 /** A customized "cannot override" error message. 1522 * @param m The overriding method. 1523 * @param other The overridden method. 1524 * @return An internationalized string. 1525 */ 1526 Object cannotOverride(MethodSymbol m, MethodSymbol other) { 1527 String key; 1528 if ((other.owner.flags() & INTERFACE) == 0) 1529 key = "cant.override"; 1530 else if ((m.owner.flags() & INTERFACE) == 0) 1531 key = "cant.implement"; 1532 else 1533 key = "clashes.with"; 1534 return diags.fragment(key, m, m.location(), other, other.location()); 1535 } 1536 1537 /** A customized "override" warning message. 1538 * @param m The overriding method. 1539 * @param other The overridden method. 1540 * @return An internationalized string. 1541 */ 1542 Object uncheckedOverrides(MethodSymbol m, MethodSymbol other) { 1543 String key; 1544 if ((other.owner.flags() & INTERFACE) == 0) 1545 key = "unchecked.override"; 1546 else if ((m.owner.flags() & INTERFACE) == 0) 1547 key = "unchecked.implement"; 1548 else 1549 key = "unchecked.clash.with"; 1550 return diags.fragment(key, m, m.location(), other, other.location()); 1551 } 1552 1553 /** A customized "override" warning message. 1554 * @param m The overriding method. 1555 * @param other The overridden method. 1556 * @return An internationalized string. 1557 */ 1558 Object varargsOverrides(MethodSymbol m, MethodSymbol other) { 1559 String key; 1560 if ((other.owner.flags() & INTERFACE) == 0) 1561 key = "varargs.override"; 1562 else if ((m.owner.flags() & INTERFACE) == 0) 1563 key = "varargs.implement"; 1564 else 1565 key = "varargs.clash.with"; 1566 return diags.fragment(key, m, m.location(), other, other.location()); 1567 } 1568 1569 /** Check that this method conforms with overridden method 'other'. 1570 * where `origin' is the class where checking started. 1571 * Complications: 1572 * (1) Do not check overriding of synthetic methods 1573 * (reason: they might be final). 1574 * todo: check whether this is still necessary. 1575 * (2) Admit the case where an interface proxy throws fewer exceptions 1576 * than the method it implements. Augment the proxy methods with the 1577 * undeclared exceptions in this case. 1578 * (3) When generics are enabled, admit the case where an interface proxy 1579 * has a result type 1580 * extended by the result type of the method it implements. 1581 * Change the proxies result type to the smaller type in this case. 1582 * 1583 * @param tree The tree from which positions 1584 * are extracted for errors. 1585 * @param m The overriding method. 1586 * @param other The overridden method. 1587 * @param origin The class of which the overriding method 1588 * is a member. 1589 */ 1590 void checkOverride(JCTree tree, 1591 MethodSymbol m, 1592 MethodSymbol other, 1593 ClassSymbol origin) { 1594 // Don't check overriding of synthetic methods or by bridge methods. 1595 if ((m.flags() & (SYNTHETIC|BRIDGE)) != 0 || (other.flags() & SYNTHETIC) != 0) { 1596 return; 1597 } 1598 1599 // Error if static method overrides instance method (JLS 8.4.6.2). 1600 if ((m.flags() & STATIC) != 0 && 1601 (other.flags() & STATIC) == 0) { 1602 log.error(TreeInfo.diagnosticPositionFor(m, tree), "override.static", 1603 cannotOverride(m, other)); 1604 m.flags_field |= BAD_OVERRIDE; 1605 return; 1606 } 1607 1608 // Error if instance method overrides static or final 1609 // method (JLS 8.4.6.1). 1610 if ((other.flags() & FINAL) != 0 || 1611 (m.flags() & STATIC) == 0 && 1612 (other.flags() & STATIC) != 0) { 1613 log.error(TreeInfo.diagnosticPositionFor(m, tree), "override.meth", 1614 cannotOverride(m, other), 1615 asFlagSet(other.flags() & (FINAL | STATIC))); 1616 m.flags_field |= BAD_OVERRIDE; 1617 return; 1618 } 1619 1620 if ((m.owner.flags() & ANNOTATION) != 0) { 1621 // handled in validateAnnotationMethod 1622 return; 1623 } 1624 1625 // Error if overriding method has weaker access (JLS 8.4.6.3). 1626 if ((origin.flags() & INTERFACE) == 0 && 1627 protection(m.flags()) > protection(other.flags())) { 1628 log.error(TreeInfo.diagnosticPositionFor(m, tree), "override.weaker.access", 1629 cannotOverride(m, other), 1630 (other.flags() & AccessFlags) == 0 ? 1631 "package" : 1632 asFlagSet(other.flags() & AccessFlags)); 1633 m.flags_field |= BAD_OVERRIDE; 1634 return; 1635 } 1636 1637 Type mt = types.memberType(origin.type, m); 1638 Type ot = types.memberType(origin.type, other); 1639 // Error if overriding result type is different 1640 // (or, in the case of generics mode, not a subtype) of 1641 // overridden result type. We have to rename any type parameters 1642 // before comparing types. 1643 List<Type> mtvars = mt.getTypeArguments(); 1644 List<Type> otvars = ot.getTypeArguments(); 1645 Type mtres = mt.getReturnType(); 1646 Type otres = types.subst(ot.getReturnType(), otvars, mtvars); 1647 1648 overrideWarner.clear(); 1649 boolean resultTypesOK = 1650 types.returnTypeSubstitutable(mt, ot, otres, overrideWarner); 1651 if (!resultTypesOK) { 1652 log.error(TreeInfo.diagnosticPositionFor(m, tree), 1653 "override.incompatible.ret", 1654 cannotOverride(m, other), 1655 mtres, otres); 1656 m.flags_field |= BAD_OVERRIDE; 1657 return; 1658 } else if (overrideWarner.hasNonSilentLint(LintCategory.UNCHECKED)) { 1659 warnUnchecked(TreeInfo.diagnosticPositionFor(m, tree), 1660 "override.unchecked.ret", 1661 uncheckedOverrides(m, other), 1662 mtres, otres); 1663 } 1664 1665 // Error if overriding method throws an exception not reported 1666 // by overridden method. 1667 List<Type> otthrown = types.subst(ot.getThrownTypes(), otvars, mtvars); 1668 List<Type> unhandledErased = unhandled(mt.getThrownTypes(), types.erasure(otthrown)); 1669 List<Type> unhandledUnerased = unhandled(mt.getThrownTypes(), otthrown); 1670 if (unhandledErased.nonEmpty()) { 1671 log.error(TreeInfo.diagnosticPositionFor(m, tree), 1672 "override.meth.doesnt.throw", 1673 cannotOverride(m, other), 1674 unhandledUnerased.head); 1675 m.flags_field |= BAD_OVERRIDE; 1676 return; 1677 } 1678 else if (unhandledUnerased.nonEmpty()) { 1679 warnUnchecked(TreeInfo.diagnosticPositionFor(m, tree), 1680 "override.unchecked.thrown", 1681 cannotOverride(m, other), 1682 unhandledUnerased.head); 1683 return; 1684 } 1685 1686 // Optional warning if varargs don't agree 1687 if ((((m.flags() ^ other.flags()) & Flags.VARARGS) != 0) 1688 && lint.isEnabled(LintCategory.OVERRIDES)) { 1689 log.warning(TreeInfo.diagnosticPositionFor(m, tree), 1690 ((m.flags() & Flags.VARARGS) != 0) 1691 ? "override.varargs.missing" 1692 : "override.varargs.extra", 1693 varargsOverrides(m, other)); 1694 } 1695 1696 // Warn if instance method overrides bridge method (compiler spec ??) 1697 if ((other.flags() & BRIDGE) != 0) { 1698 log.warning(TreeInfo.diagnosticPositionFor(m, tree), "override.bridge", 1699 uncheckedOverrides(m, other)); 1700 } 1701 1702 // Warn if a deprecated method overridden by a non-deprecated one. 1703 if (!isDeprecatedOverrideIgnorable(other, origin)) { 1704 Lint prevLint = setLint(lint.augment(m)); 1705 try { 1706 checkDeprecated(TreeInfo.diagnosticPositionFor(m, tree), m, other); 1707 } finally { 1708 setLint(prevLint); 1709 } 1710 } 1711 } 1712 // where 1713 private boolean isDeprecatedOverrideIgnorable(MethodSymbol m, ClassSymbol origin) { 1714 // If the method, m, is defined in an interface, then ignore the issue if the method 1715 // is only inherited via a supertype and also implemented in the supertype, 1716 // because in that case, we will rediscover the issue when examining the method 1717 // in the supertype. 1718 // If the method, m, is not defined in an interface, then the only time we need to 1719 // address the issue is when the method is the supertype implemementation: any other 1720 // case, we will have dealt with when examining the supertype classes 1721 ClassSymbol mc = m.enclClass(); 1722 Type st = types.supertype(origin.type); 1723 if (!st.hasTag(CLASS)) 1724 return true; 1725 MethodSymbol stimpl = m.implementation((ClassSymbol)st.tsym, types, false); 1726 1727 if (mc != null && ((mc.flags() & INTERFACE) != 0)) { 1728 List<Type> intfs = types.interfaces(origin.type); 1729 return (intfs.contains(mc.type) ? false : (stimpl != null)); 1730 } 1731 else 1732 return (stimpl != m); 1733 } 1734 1735 1736 // used to check if there were any unchecked conversions 1737 Warner overrideWarner = new Warner(); 1738 1739 /** Check that a class does not inherit two concrete methods 1740 * with the same signature. 1741 * @param pos Position to be used for error reporting. 1742 * @param site The class type to be checked. 1743 */ 1744 public void checkCompatibleConcretes(DiagnosticPosition pos, Type site) { 1745 Type sup = types.supertype(site); 1746 if (!sup.hasTag(CLASS)) return; 1747 1748 for (Type t1 = sup; 1749 t1.hasTag(CLASS) && t1.tsym.type.isParameterized(); 1750 t1 = types.supertype(t1)) { 1751 for (Symbol s1 : t1.tsym.members().getSymbols(NON_RECURSIVE)) { 1752 if (s1.kind != MTH || 1753 (s1.flags() & (STATIC|SYNTHETIC|BRIDGE)) != 0 || 1754 !s1.isInheritedIn(site.tsym, types) || 1755 ((MethodSymbol)s1).implementation(site.tsym, 1756 types, 1757 true) != s1) 1758 continue; 1759 Type st1 = types.memberType(t1, s1); 1760 int s1ArgsLength = st1.getParameterTypes().length(); 1761 if (st1 == s1.type) continue; 1762 1763 for (Type t2 = sup; 1764 t2.hasTag(CLASS); 1765 t2 = types.supertype(t2)) { 1766 for (Symbol s2 : t2.tsym.members().getSymbolsByName(s1.name)) { 1767 if (s2 == s1 || 1768 s2.kind != MTH || 1769 (s2.flags() & (STATIC|SYNTHETIC|BRIDGE)) != 0 || 1770 s2.type.getParameterTypes().length() != s1ArgsLength || 1771 !s2.isInheritedIn(site.tsym, types) || 1772 ((MethodSymbol)s2).implementation(site.tsym, 1773 types, 1774 true) != s2) 1775 continue; 1776 Type st2 = types.memberType(t2, s2); 1777 if (types.overrideEquivalent(st1, st2)) 1778 log.error(pos, "concrete.inheritance.conflict", 1779 s1, t1, s2, t2, sup); 1780 } 1781 } 1782 } 1783 } 1784 } 1785 1786 /** Check that classes (or interfaces) do not each define an abstract 1787 * method with same name and arguments but incompatible return types. 1788 * @param pos Position to be used for error reporting. 1789 * @param t1 The first argument type. 1790 * @param t2 The second argument type. 1791 */ 1792 public boolean checkCompatibleAbstracts(DiagnosticPosition pos, 1793 Type t1, 1794 Type t2, 1795 Type site) { 1796 if ((site.tsym.flags() & COMPOUND) != 0) { 1797 // special case for intersections: need to eliminate wildcards in supertypes 1798 t1 = types.capture(t1); 1799 t2 = types.capture(t2); 1800 } 1801 return firstIncompatibility(pos, t1, t2, site) == null; 1802 } 1803 1804 /** Return the first method which is defined with same args 1805 * but different return types in two given interfaces, or null if none 1806 * exists. 1807 * @param t1 The first type. 1808 * @param t2 The second type. 1809 * @param site The most derived type. 1810 * @returns symbol from t2 that conflicts with one in t1. 1811 */ 1812 private Symbol firstIncompatibility(DiagnosticPosition pos, Type t1, Type t2, Type site) { 1813 Map<TypeSymbol,Type> interfaces1 = new HashMap<>(); 1814 closure(t1, interfaces1); 1815 Map<TypeSymbol,Type> interfaces2; 1816 if (t1 == t2) 1817 interfaces2 = interfaces1; 1818 else 1819 closure(t2, interfaces1, interfaces2 = new HashMap<>()); 1820 1821 for (Type t3 : interfaces1.values()) { 1822 for (Type t4 : interfaces2.values()) { 1823 Symbol s = firstDirectIncompatibility(pos, t3, t4, site); 1824 if (s != null) return s; 1825 } 1826 } 1827 return null; 1828 } 1829 1830 /** Compute all the supertypes of t, indexed by type symbol. */ 1831 private void closure(Type t, Map<TypeSymbol,Type> typeMap) { 1832 if (!t.hasTag(CLASS)) return; 1833 if (typeMap.put(t.tsym, t) == null) { 1834 closure(types.supertype(t), typeMap); 1835 for (Type i : types.interfaces(t)) 1836 closure(i, typeMap); 1837 } 1838 } 1839 1840 /** Compute all the supertypes of t, indexed by type symbol (except thise in typesSkip). */ 1841 private void closure(Type t, Map<TypeSymbol,Type> typesSkip, Map<TypeSymbol,Type> typeMap) { 1842 if (!t.hasTag(CLASS)) return; 1843 if (typesSkip.get(t.tsym) != null) return; 1844 if (typeMap.put(t.tsym, t) == null) { 1845 closure(types.supertype(t), typesSkip, typeMap); 1846 for (Type i : types.interfaces(t)) 1847 closure(i, typesSkip, typeMap); 1848 } 1849 } 1850 1851 /** Return the first method in t2 that conflicts with a method from t1. */ 1852 private Symbol firstDirectIncompatibility(DiagnosticPosition pos, Type t1, Type t2, Type site) { 1853 for (Symbol s1 : t1.tsym.members().getSymbols(NON_RECURSIVE)) { 1854 Type st1 = null; 1855 if (s1.kind != MTH || !s1.isInheritedIn(site.tsym, types) || 1856 (s1.flags() & SYNTHETIC) != 0) continue; 1857 Symbol impl = ((MethodSymbol)s1).implementation(site.tsym, types, false); 1858 if (impl != null && (impl.flags() & ABSTRACT) == 0) continue; 1859 for (Symbol s2 : t2.tsym.members().getSymbolsByName(s1.name)) { 1860 if (s1 == s2) continue; 1861 if (s2.kind != MTH || !s2.isInheritedIn(site.tsym, types) || 1862 (s2.flags() & SYNTHETIC) != 0) continue; 1863 if (st1 == null) st1 = types.memberType(t1, s1); 1864 Type st2 = types.memberType(t2, s2); 1865 if (types.overrideEquivalent(st1, st2)) { 1866 List<Type> tvars1 = st1.getTypeArguments(); 1867 List<Type> tvars2 = st2.getTypeArguments(); 1868 Type rt1 = st1.getReturnType(); 1869 Type rt2 = types.subst(st2.getReturnType(), tvars2, tvars1); 1870 boolean compat = 1871 types.isSameType(rt1, rt2) || 1872 !rt1.isPrimitiveOrVoid() && 1873 !rt2.isPrimitiveOrVoid() && 1874 (types.covariantReturnType(rt1, rt2, types.noWarnings) || 1875 types.covariantReturnType(rt2, rt1, types.noWarnings)) || 1876 checkCommonOverriderIn(s1,s2,site); 1877 if (!compat) { 1878 log.error(pos, "types.incompatible.diff.ret", 1879 t1, t2, s2.name + 1880 "(" + types.memberType(t2, s2).getParameterTypes() + ")"); 1881 return s2; 1882 } 1883 } else if (checkNameClash((ClassSymbol)site.tsym, s1, s2) && 1884 !checkCommonOverriderIn(s1, s2, site)) { 1885 log.error(pos, 1886 "name.clash.same.erasure.no.override", 1887 s1, s1.location(), 1888 s2, s2.location()); 1889 return s2; 1890 } 1891 } 1892 } 1893 return null; 1894 } 1895 //WHERE 1896 boolean checkCommonOverriderIn(Symbol s1, Symbol s2, Type site) { 1897 Map<TypeSymbol,Type> supertypes = new HashMap<>(); 1898 Type st1 = types.memberType(site, s1); 1899 Type st2 = types.memberType(site, s2); 1900 closure(site, supertypes); 1901 for (Type t : supertypes.values()) { 1902 for (Symbol s3 : t.tsym.members().getSymbolsByName(s1.name)) { 1903 if (s3 == s1 || s3 == s2 || s3.kind != MTH || (s3.flags() & (BRIDGE|SYNTHETIC)) != 0) continue; 1904 Type st3 = types.memberType(site,s3); 1905 if (types.overrideEquivalent(st3, st1) && 1906 types.overrideEquivalent(st3, st2) && 1907 types.returnTypeSubstitutable(st3, st1) && 1908 types.returnTypeSubstitutable(st3, st2)) { 1909 return true; 1910 } 1911 } 1912 } 1913 return false; 1914 } 1915 1916 /** Check that a given method conforms with any method it overrides. 1917 * @param tree The tree from which positions are extracted 1918 * for errors. 1919 * @param m The overriding method. 1920 */ 1921 void checkOverride(JCMethodDecl tree, MethodSymbol m) { 1922 ClassSymbol origin = (ClassSymbol)m.owner; 1923 if ((origin.flags() & ENUM) != 0 && names.finalize.equals(m.name)) 1924 if (m.overrides(syms.enumFinalFinalize, origin, types, false)) { 1925 log.error(tree.pos(), "enum.no.finalize"); 1926 return; 1927 } 1928 for (Type t = origin.type; t.hasTag(CLASS); 1929 t = types.supertype(t)) { 1930 if (t != origin.type) { 1931 checkOverride(tree, t, origin, m); 1932 } 1933 for (Type t2 : types.interfaces(t)) { 1934 checkOverride(tree, t2, origin, m); 1935 } 1936 } 1937 1938 if (m.attribute(syms.overrideType.tsym) != null && !isOverrider(m)) { 1939 DiagnosticPosition pos = tree.pos(); 1940 for (JCAnnotation a : tree.getModifiers().annotations) { 1941 if (a.annotationType.type.tsym == syms.overrideType.tsym) { 1942 pos = a.pos(); 1943 break; 1944 } 1945 } 1946 log.error(pos, "method.does.not.override.superclass"); 1947 } 1948 } 1949 1950 void checkOverride(JCTree tree, Type site, ClassSymbol origin, MethodSymbol m) { 1951 TypeSymbol c = site.tsym; 1952 for (Symbol sym : c.members().getSymbolsByName(m.name)) { 1953 if (m.overrides(sym, origin, types, false)) { 1954 if ((sym.flags() & ABSTRACT) == 0) { 1955 checkOverride(tree, m, (MethodSymbol)sym, origin); 1956 } 1957 } 1958 } 1959 } 1960 1961 private Filter<Symbol> equalsHasCodeFilter = new Filter<Symbol>() { 1962 public boolean accepts(Symbol s) { 1963 return MethodSymbol.implementation_filter.accepts(s) && 1964 (s.flags() & BAD_OVERRIDE) == 0; 1965 1966 } 1967 }; 1968 1969 public void checkClassOverrideEqualsAndHashIfNeeded(DiagnosticPosition pos, 1970 ClassSymbol someClass) { 1971 /* At present, annotations cannot possibly have a method that is override 1972 * equivalent with Object.equals(Object) but in any case the condition is 1973 * fine for completeness. 1974 */ 1975 if (someClass == (ClassSymbol)syms.objectType.tsym || 1976 someClass.isInterface() || someClass.isEnum() || 1977 (someClass.flags() & ANNOTATION) != 0 || 1978 (someClass.flags() & ABSTRACT) != 0) return; 1979 //anonymous inner classes implementing interfaces need especial treatment 1980 if (someClass.isAnonymous()) { 1981 List<Type> interfaces = types.interfaces(someClass.type); 1982 if (interfaces != null && !interfaces.isEmpty() && 1983 interfaces.head.tsym == syms.comparatorType.tsym) return; 1984 } 1985 checkClassOverrideEqualsAndHash(pos, someClass); 1986 } 1987 1988 private void checkClassOverrideEqualsAndHash(DiagnosticPosition pos, 1989 ClassSymbol someClass) { 1990 if (lint.isEnabled(LintCategory.OVERRIDES)) { 1991 MethodSymbol equalsAtObject = (MethodSymbol)syms.objectType 1992 .tsym.members().findFirst(names.equals); 1993 MethodSymbol hashCodeAtObject = (MethodSymbol)syms.objectType 1994 .tsym.members().findFirst(names.hashCode); 1995 boolean overridesEquals = types.implementation(equalsAtObject, 1996 someClass, false, equalsHasCodeFilter).owner == someClass; 1997 boolean overridesHashCode = types.implementation(hashCodeAtObject, 1998 someClass, false, equalsHasCodeFilter) != hashCodeAtObject; 1999 2000 if (overridesEquals && !overridesHashCode) { 2001 log.warning(LintCategory.OVERRIDES, pos, 2002 "override.equals.but.not.hashcode", someClass); 2003 } 2004 } 2005 } 2006 2007 private boolean checkNameClash(ClassSymbol origin, Symbol s1, Symbol s2) { 2008 ClashFilter cf = new ClashFilter(origin.type); 2009 return (cf.accepts(s1) && 2010 cf.accepts(s2) && 2011 types.hasSameArgs(s1.erasure(types), s2.erasure(types))); 2012 } 2013 2014 2015 /** Check that all abstract members of given class have definitions. 2016 * @param pos Position to be used for error reporting. 2017 * @param c The class. 2018 */ 2019 void checkAllDefined(DiagnosticPosition pos, ClassSymbol c) { 2020 MethodSymbol undef = types.firstUnimplementedAbstract(c); 2021 if (undef != null) { 2022 MethodSymbol undef1 = 2023 new MethodSymbol(undef.flags(), undef.name, 2024 types.memberType(c.type, undef), undef.owner); 2025 log.error(pos, "does.not.override.abstract", 2026 c, undef1, undef1.location()); 2027 } 2028 } 2029 2030 void checkNonCyclicDecl(JCClassDecl tree) { 2031 CycleChecker cc = new CycleChecker(); 2032 cc.scan(tree); 2033 if (!cc.errorFound && !cc.partialCheck) { 2034 tree.sym.flags_field |= ACYCLIC; 2035 } 2036 } 2037 2038 class CycleChecker extends TreeScanner { 2039 2040 List<Symbol> seenClasses = List.nil(); 2041 boolean errorFound = false; 2042 boolean partialCheck = false; 2043 2044 private void checkSymbol(DiagnosticPosition pos, Symbol sym) { 2045 if (sym != null && sym.kind == TYP) { 2046 Env<AttrContext> classEnv = enter.getEnv((TypeSymbol)sym); 2047 if (classEnv != null) { 2048 DiagnosticSource prevSource = log.currentSource(); 2049 try { 2050 log.useSource(classEnv.toplevel.sourcefile); 2051 scan(classEnv.tree); 2052 } 2053 finally { 2054 log.useSource(prevSource.getFile()); 2055 } 2056 } else if (sym.kind == TYP) { 2057 checkClass(pos, sym, List.<JCTree>nil()); 2058 } 2059 } else { 2060 //not completed yet 2061 partialCheck = true; 2062 } 2063 } 2064 2065 @Override 2066 public void visitSelect(JCFieldAccess tree) { 2067 super.visitSelect(tree); 2068 checkSymbol(tree.pos(), tree.sym); 2069 } 2070 2071 @Override 2072 public void visitIdent(JCIdent tree) { 2073 checkSymbol(tree.pos(), tree.sym); 2074 } 2075 2076 @Override 2077 public void visitTypeApply(JCTypeApply tree) { 2078 scan(tree.clazz); 2079 } 2080 2081 @Override 2082 public void visitTypeArray(JCArrayTypeTree tree) { 2083 scan(tree.elemtype); 2084 } 2085 2086 @Override 2087 public void visitClassDef(JCClassDecl tree) { 2088 List<JCTree> supertypes = List.nil(); 2089 if (tree.getExtendsClause() != null) { 2090 supertypes = supertypes.prepend(tree.getExtendsClause()); 2091 } 2092 if (tree.getImplementsClause() != null) { 2093 for (JCTree intf : tree.getImplementsClause()) { 2094 supertypes = supertypes.prepend(intf); 2095 } 2096 } 2097 checkClass(tree.pos(), tree.sym, supertypes); 2098 } 2099 2100 void checkClass(DiagnosticPosition pos, Symbol c, List<JCTree> supertypes) { 2101 if ((c.flags_field & ACYCLIC) != 0) 2102 return; 2103 if (seenClasses.contains(c)) { 2104 errorFound = true; 2105 noteCyclic(pos, (ClassSymbol)c); 2106 } else if (!c.type.isErroneous()) { 2107 try { 2108 seenClasses = seenClasses.prepend(c); 2109 if (c.type.hasTag(CLASS)) { 2110 if (supertypes.nonEmpty()) { 2111 scan(supertypes); 2112 } 2113 else { 2114 ClassType ct = (ClassType)c.type; 2115 if (ct.supertype_field == null || 2116 ct.interfaces_field == null) { 2117 //not completed yet 2118 partialCheck = true; 2119 return; 2120 } 2121 checkSymbol(pos, ct.supertype_field.tsym); 2122 for (Type intf : ct.interfaces_field) { 2123 checkSymbol(pos, intf.tsym); 2124 } 2125 } 2126 if (c.owner.kind == TYP) { 2127 checkSymbol(pos, c.owner); 2128 } 2129 } 2130 } finally { 2131 seenClasses = seenClasses.tail; 2132 } 2133 } 2134 } 2135 } 2136 2137 /** Check for cyclic references. Issue an error if the 2138 * symbol of the type referred to has a LOCKED flag set. 2139 * 2140 * @param pos Position to be used for error reporting. 2141 * @param t The type referred to. 2142 */ 2143 void checkNonCyclic(DiagnosticPosition pos, Type t) { 2144 checkNonCyclicInternal(pos, t); 2145 } 2146 2147 2148 void checkNonCyclic(DiagnosticPosition pos, TypeVar t) { 2149 checkNonCyclic1(pos, t, List.<TypeVar>nil()); 2150 } 2151 2152 private void checkNonCyclic1(DiagnosticPosition pos, Type t, List<TypeVar> seen) { 2153 final TypeVar tv; 2154 if (t.hasTag(TYPEVAR) && (t.tsym.flags() & UNATTRIBUTED) != 0) 2155 return; 2156 if (seen.contains(t)) { 2157 tv = (TypeVar)t; 2158 tv.bound = types.createErrorType(t); 2159 log.error(pos, "cyclic.inheritance", t); 2160 } else if (t.hasTag(TYPEVAR)) { 2161 tv = (TypeVar)t; 2162 seen = seen.prepend(tv); 2163 for (Type b : types.getBounds(tv)) 2164 checkNonCyclic1(pos, b, seen); 2165 } 2166 } 2167 2168 /** Check for cyclic references. Issue an error if the 2169 * symbol of the type referred to has a LOCKED flag set. 2170 * 2171 * @param pos Position to be used for error reporting. 2172 * @param t The type referred to. 2173 * @returns True if the check completed on all attributed classes 2174 */ 2175 private boolean checkNonCyclicInternal(DiagnosticPosition pos, Type t) { 2176 boolean complete = true; // was the check complete? 2177 //- System.err.println("checkNonCyclicInternal("+t+");");//DEBUG 2178 Symbol c = t.tsym; 2179 if ((c.flags_field & ACYCLIC) != 0) return true; 2180 2181 if ((c.flags_field & LOCKED) != 0) { 2182 noteCyclic(pos, (ClassSymbol)c); 2183 } else if (!c.type.isErroneous()) { 2184 try { 2185 c.flags_field |= LOCKED; 2186 if (c.type.hasTag(CLASS)) { 2187 ClassType clazz = (ClassType)c.type; 2188 if (clazz.interfaces_field != null) 2189 for (List<Type> l=clazz.interfaces_field; l.nonEmpty(); l=l.tail) 2190 complete &= checkNonCyclicInternal(pos, l.head); 2191 if (clazz.supertype_field != null) { 2192 Type st = clazz.supertype_field; 2193 if (st != null && st.hasTag(CLASS)) 2194 complete &= checkNonCyclicInternal(pos, st); 2195 } 2196 if (c.owner.kind == TYP) 2197 complete &= checkNonCyclicInternal(pos, c.owner.type); 2198 } 2199 } finally { 2200 c.flags_field &= ~LOCKED; 2201 } 2202 } 2203 if (complete) 2204 complete = ((c.flags_field & UNATTRIBUTED) == 0) && c.completer == null; 2205 if (complete) c.flags_field |= ACYCLIC; 2206 return complete; 2207 } 2208 2209 /** Note that we found an inheritance cycle. */ 2210 private void noteCyclic(DiagnosticPosition pos, ClassSymbol c) { 2211 log.error(pos, "cyclic.inheritance", c); 2212 for (List<Type> l=types.interfaces(c.type); l.nonEmpty(); l=l.tail) 2213 l.head = types.createErrorType((ClassSymbol)l.head.tsym, Type.noType); 2214 Type st = types.supertype(c.type); 2215 if (st.hasTag(CLASS)) 2216 ((ClassType)c.type).supertype_field = types.createErrorType((ClassSymbol)st.tsym, Type.noType); 2217 c.type = types.createErrorType(c, c.type); 2218 c.flags_field |= ACYCLIC; 2219 } 2220 2221 /** Check that all methods which implement some 2222 * method conform to the method they implement. 2223 * @param tree The class definition whose members are checked. 2224 */ 2225 void checkImplementations(JCClassDecl tree) { 2226 checkImplementations(tree, tree.sym, tree.sym); 2227 } 2228 //where 2229 /** Check that all methods which implement some 2230 * method in `ic' conform to the method they implement. 2231 */ 2232 void checkImplementations(JCTree tree, ClassSymbol origin, ClassSymbol ic) { 2233 for (List<Type> l = types.closure(ic.type); l.nonEmpty(); l = l.tail) { 2234 ClassSymbol lc = (ClassSymbol)l.head.tsym; 2235 if ((lc.flags() & ABSTRACT) != 0) { 2236 for (Symbol sym : lc.members().getSymbols(NON_RECURSIVE)) { 2237 if (sym.kind == MTH && 2238 (sym.flags() & (STATIC|ABSTRACT)) == ABSTRACT) { 2239 MethodSymbol absmeth = (MethodSymbol)sym; 2240 MethodSymbol implmeth = absmeth.implementation(origin, types, false); 2241 if (implmeth != null && implmeth != absmeth && 2242 (implmeth.owner.flags() & INTERFACE) == 2243 (origin.flags() & INTERFACE)) { 2244 // don't check if implmeth is in a class, yet 2245 // origin is an interface. This case arises only 2246 // if implmeth is declared in Object. The reason is 2247 // that interfaces really don't inherit from 2248 // Object it's just that the compiler represents 2249 // things that way. 2250 checkOverride(tree, implmeth, absmeth, origin); 2251 } 2252 } 2253 } 2254 } 2255 } 2256 } 2257 2258 /** Check that all abstract methods implemented by a class are 2259 * mutually compatible. 2260 * @param pos Position to be used for error reporting. 2261 * @param c The class whose interfaces are checked. 2262 */ 2263 void checkCompatibleSupertypes(DiagnosticPosition pos, Type c) { 2264 List<Type> supertypes = types.interfaces(c); 2265 Type supertype = types.supertype(c); 2266 if (supertype.hasTag(CLASS) && 2267 (supertype.tsym.flags() & ABSTRACT) != 0) 2268 supertypes = supertypes.prepend(supertype); 2269 for (List<Type> l = supertypes; l.nonEmpty(); l = l.tail) { 2270 if (!l.head.getTypeArguments().isEmpty() && 2271 !checkCompatibleAbstracts(pos, l.head, l.head, c)) 2272 return; 2273 for (List<Type> m = supertypes; m != l; m = m.tail) 2274 if (!checkCompatibleAbstracts(pos, l.head, m.head, c)) 2275 return; 2276 } 2277 checkCompatibleConcretes(pos, c); 2278 } 2279 2280 void checkConflicts(DiagnosticPosition pos, Symbol sym, TypeSymbol c) { 2281 for (Type ct = c.type; ct != Type.noType ; ct = types.supertype(ct)) { 2282 for (Symbol sym2 : ct.tsym.members().getSymbolsByName(sym.name, NON_RECURSIVE)) { 2283 // VM allows methods and variables with differing types 2284 if (sym.kind == sym2.kind && 2285 types.isSameType(types.erasure(sym.type), types.erasure(sym2.type)) && 2286 sym != sym2 && 2287 (sym.flags() & Flags.SYNTHETIC) != (sym2.flags() & Flags.SYNTHETIC) && 2288 (sym.flags() & IPROXY) == 0 && (sym2.flags() & IPROXY) == 0 && 2289 (sym.flags() & BRIDGE) == 0 && (sym2.flags() & BRIDGE) == 0) { 2290 syntheticError(pos, (sym2.flags() & SYNTHETIC) == 0 ? sym2 : sym); 2291 return; 2292 } 2293 } 2294 } 2295 } 2296 2297 /** Check that all non-override equivalent methods accessible from 'site' 2298 * are mutually compatible (JLS 8.4.8/9.4.1). 2299 * 2300 * @param pos Position to be used for error reporting. 2301 * @param site The class whose methods are checked. 2302 * @param sym The method symbol to be checked. 2303 */ 2304 void checkOverrideClashes(DiagnosticPosition pos, Type site, MethodSymbol sym) { 2305 ClashFilter cf = new ClashFilter(site); 2306 //for each method m1 that is overridden (directly or indirectly) 2307 //by method 'sym' in 'site'... 2308 2309 List<MethodSymbol> potentiallyAmbiguousList = List.nil(); 2310 boolean overridesAny = false; 2311 for (Symbol m1 : types.membersClosure(site, false).getSymbolsByName(sym.name, cf)) { 2312 if (!sym.overrides(m1, site.tsym, types, false)) { 2313 if (m1 == sym) { 2314 continue; 2315 } 2316 2317 if (!overridesAny) { 2318 potentiallyAmbiguousList = potentiallyAmbiguousList.prepend((MethodSymbol)m1); 2319 } 2320 continue; 2321 } 2322 2323 if (m1 != sym) { 2324 overridesAny = true; 2325 potentiallyAmbiguousList = List.nil(); 2326 } 2327 2328 //...check each method m2 that is a member of 'site' 2329 for (Symbol m2 : types.membersClosure(site, false).getSymbolsByName(sym.name, cf)) { 2330 if (m2 == m1) continue; 2331 //if (i) the signature of 'sym' is not a subsignature of m1 (seen as 2332 //a member of 'site') and (ii) m1 has the same erasure as m2, issue an error 2333 if (!types.isSubSignature(sym.type, types.memberType(site, m2), allowStrictMethodClashCheck) && 2334 types.hasSameArgs(m2.erasure(types), m1.erasure(types))) { 2335 sym.flags_field |= CLASH; 2336 String key = m1 == sym ? 2337 "name.clash.same.erasure.no.override" : 2338 "name.clash.same.erasure.no.override.1"; 2339 log.error(pos, 2340 key, 2341 sym, sym.location(), 2342 m2, m2.location(), 2343 m1, m1.location()); 2344 return; 2345 } 2346 } 2347 } 2348 2349 if (!overridesAny) { 2350 for (MethodSymbol m: potentiallyAmbiguousList) { 2351 checkPotentiallyAmbiguousOverloads(pos, site, sym, m); 2352 } 2353 } 2354 } 2355 2356 /** Check that all static methods accessible from 'site' are 2357 * mutually compatible (JLS 8.4.8). 2358 * 2359 * @param pos Position to be used for error reporting. 2360 * @param site The class whose methods are checked. 2361 * @param sym The method symbol to be checked. 2362 */ 2363 void checkHideClashes(DiagnosticPosition pos, Type site, MethodSymbol sym) { 2364 ClashFilter cf = new ClashFilter(site); 2365 //for each method m1 that is a member of 'site'... 2366 for (Symbol s : types.membersClosure(site, true).getSymbolsByName(sym.name, cf)) { 2367 //if (i) the signature of 'sym' is not a subsignature of m1 (seen as 2368 //a member of 'site') and (ii) 'sym' has the same erasure as m1, issue an error 2369 if (!types.isSubSignature(sym.type, types.memberType(site, s), allowStrictMethodClashCheck)) { 2370 if (types.hasSameArgs(s.erasure(types), sym.erasure(types))) { 2371 log.error(pos, 2372 "name.clash.same.erasure.no.hide", 2373 sym, sym.location(), 2374 s, s.location()); 2375 return; 2376 } else { 2377 checkPotentiallyAmbiguousOverloads(pos, site, sym, (MethodSymbol)s); 2378 } 2379 } 2380 } 2381 } 2382 2383 //where 2384 private class ClashFilter implements Filter<Symbol> { 2385 2386 Type site; 2387 2388 ClashFilter(Type site) { 2389 this.site = site; 2390 } 2391 2392 boolean shouldSkip(Symbol s) { 2393 return (s.flags() & CLASH) != 0 && 2394 s.owner == site.tsym; 2395 } 2396 2397 public boolean accepts(Symbol s) { 2398 return s.kind == MTH && 2399 (s.flags() & SYNTHETIC) == 0 && 2400 !shouldSkip(s) && 2401 s.isInheritedIn(site.tsym, types) && 2402 !s.isConstructor(); 2403 } 2404 } 2405 2406 void checkDefaultMethodClashes(DiagnosticPosition pos, Type site) { 2407 DefaultMethodClashFilter dcf = new DefaultMethodClashFilter(site); 2408 for (Symbol m : types.membersClosure(site, false).getSymbols(dcf)) { 2409 Assert.check(m.kind == MTH); 2410 List<MethodSymbol> prov = types.interfaceCandidates(site, (MethodSymbol)m); 2411 if (prov.size() > 1) { 2412 ListBuffer<Symbol> abstracts = new ListBuffer<>(); 2413 ListBuffer<Symbol> defaults = new ListBuffer<>(); 2414 for (MethodSymbol provSym : prov) { 2415 if ((provSym.flags() & DEFAULT) != 0) { 2416 defaults = defaults.append(provSym); 2417 } else if ((provSym.flags() & ABSTRACT) != 0) { 2418 abstracts = abstracts.append(provSym); 2419 } 2420 if (defaults.nonEmpty() && defaults.size() + abstracts.size() >= 2) { 2421 //strong semantics - issue an error if two sibling interfaces 2422 //have two override-equivalent defaults - or if one is abstract 2423 //and the other is default 2424 String errKey; 2425 Symbol s1 = defaults.first(); 2426 Symbol s2; 2427 if (defaults.size() > 1) { 2428 errKey = "types.incompatible.unrelated.defaults"; 2429 s2 = defaults.toList().tail.head; 2430 } else { 2431 errKey = "types.incompatible.abstract.default"; 2432 s2 = abstracts.first(); 2433 } 2434 log.error(pos, errKey, 2435 Kinds.kindName(site.tsym), site, 2436 m.name, types.memberType(site, m).getParameterTypes(), 2437 s1.location(), s2.location()); 2438 break; 2439 } 2440 } 2441 } 2442 } 2443 } 2444 2445 //where 2446 private class DefaultMethodClashFilter implements Filter<Symbol> { 2447 2448 Type site; 2449 2450 DefaultMethodClashFilter(Type site) { 2451 this.site = site; 2452 } 2453 2454 public boolean accepts(Symbol s) { 2455 return s.kind == MTH && 2456 (s.flags() & DEFAULT) != 0 && 2457 s.isInheritedIn(site.tsym, types) && 2458 !s.isConstructor(); 2459 } 2460 } 2461 2462 /** 2463 * Report warnings for potentially ambiguous method declarations. Two declarations 2464 * are potentially ambiguous if they feature two unrelated functional interface 2465 * in same argument position (in which case, a call site passing an implicit 2466 * lambda would be ambiguous). 2467 */ 2468 void checkPotentiallyAmbiguousOverloads(DiagnosticPosition pos, Type site, 2469 MethodSymbol msym1, MethodSymbol msym2) { 2470 if (msym1 != msym2 && 2471 allowDefaultMethods && 2472 lint.isEnabled(LintCategory.OVERLOADS) && 2473 (msym1.flags() & POTENTIALLY_AMBIGUOUS) == 0 && 2474 (msym2.flags() & POTENTIALLY_AMBIGUOUS) == 0) { 2475 Type mt1 = types.memberType(site, msym1); 2476 Type mt2 = types.memberType(site, msym2); 2477 //if both generic methods, adjust type variables 2478 if (mt1.hasTag(FORALL) && mt2.hasTag(FORALL) && 2479 types.hasSameBounds((ForAll)mt1, (ForAll)mt2)) { 2480 mt2 = types.subst(mt2, ((ForAll)mt2).tvars, ((ForAll)mt1).tvars); 2481 } 2482 //expand varargs methods if needed 2483 int maxLength = Math.max(mt1.getParameterTypes().length(), mt2.getParameterTypes().length()); 2484 List<Type> args1 = rs.adjustArgs(mt1.getParameterTypes(), msym1, maxLength, true); 2485 List<Type> args2 = rs.adjustArgs(mt2.getParameterTypes(), msym2, maxLength, true); 2486 //if arities don't match, exit 2487 if (args1.length() != args2.length()) return; 2488 boolean potentiallyAmbiguous = false; 2489 while (args1.nonEmpty() && args2.nonEmpty()) { 2490 Type s = args1.head; 2491 Type t = args2.head; 2492 if (!types.isSubtype(t, s) && !types.isSubtype(s, t)) { 2493 if (types.isFunctionalInterface(s) && types.isFunctionalInterface(t) && 2494 types.findDescriptorType(s).getParameterTypes().length() > 0 && 2495 types.findDescriptorType(s).getParameterTypes().length() == 2496 types.findDescriptorType(t).getParameterTypes().length()) { 2497 potentiallyAmbiguous = true; 2498 } else { 2499 break; 2500 } 2501 } 2502 args1 = args1.tail; 2503 args2 = args2.tail; 2504 } 2505 if (potentiallyAmbiguous) { 2506 //we found two incompatible functional interfaces with same arity 2507 //this means a call site passing an implicit lambda would be ambigiuous 2508 msym1.flags_field |= POTENTIALLY_AMBIGUOUS; 2509 msym2.flags_field |= POTENTIALLY_AMBIGUOUS; 2510 log.warning(LintCategory.OVERLOADS, pos, "potentially.ambiguous.overload", 2511 msym1, msym1.location(), 2512 msym2, msym2.location()); 2513 return; 2514 } 2515 } 2516 } 2517 2518 void checkElemAccessFromSerializableLambda(final JCTree tree) { 2519 if (warnOnAccessToSensitiveMembers) { 2520 Symbol sym = TreeInfo.symbol(tree); 2521 if (!sym.kind.matches(KindSelector.VAL_MTH)) { 2522 return; 2523 } 2524 2525 if (sym.kind == VAR) { 2526 if ((sym.flags() & PARAMETER) != 0 || 2527 sym.isLocal() || 2528 sym.name == names._this || 2529 sym.name == names._super) { 2530 return; 2531 } 2532 } 2533 2534 if (!types.isSubtype(sym.owner.type, syms.serializableType) && 2535 isEffectivelyNonPublic(sym)) { 2536 log.warning(tree.pos(), 2537 "access.to.sensitive.member.from.serializable.element", sym); 2538 } 2539 } 2540 } 2541 2542 private boolean isEffectivelyNonPublic(Symbol sym) { 2543 if (sym.packge() == syms.rootPackage) { 2544 return false; 2545 } 2546 2547 while (sym.kind != PCK) { 2548 if ((sym.flags() & PUBLIC) == 0) { 2549 return true; 2550 } 2551 sym = sym.owner; 2552 } 2553 return false; 2554 } 2555 2556 /** Report a conflict between a user symbol and a synthetic symbol. 2557 */ 2558 private void syntheticError(DiagnosticPosition pos, Symbol sym) { 2559 if (!sym.type.isErroneous()) { 2560 if (warnOnSyntheticConflicts) { 2561 log.warning(pos, "synthetic.name.conflict", sym, sym.location()); 2562 } 2563 else { 2564 log.error(pos, "synthetic.name.conflict", sym, sym.location()); 2565 } 2566 } 2567 } 2568 2569 /** Check that class c does not implement directly or indirectly 2570 * the same parameterized interface with two different argument lists. 2571 * @param pos Position to be used for error reporting. 2572 * @param type The type whose interfaces are checked. 2573 */ 2574 void checkClassBounds(DiagnosticPosition pos, Type type) { 2575 checkClassBounds(pos, new HashMap<TypeSymbol,Type>(), type); 2576 } 2577//where 2578 /** Enter all interfaces of type `type' into the hash table `seensofar' 2579 * with their class symbol as key and their type as value. Make 2580 * sure no class is entered with two different types. 2581 */ 2582 void checkClassBounds(DiagnosticPosition pos, 2583 Map<TypeSymbol,Type> seensofar, 2584 Type type) { 2585 if (type.isErroneous()) return; 2586 for (List<Type> l = types.interfaces(type); l.nonEmpty(); l = l.tail) { 2587 Type it = l.head; 2588 Type oldit = seensofar.put(it.tsym, it); 2589 if (oldit != null) { 2590 List<Type> oldparams = oldit.allparams(); 2591 List<Type> newparams = it.allparams(); 2592 if (!types.containsTypeEquivalent(oldparams, newparams)) 2593 log.error(pos, "cant.inherit.diff.arg", 2594 it.tsym, Type.toString(oldparams), 2595 Type.toString(newparams)); 2596 } 2597 checkClassBounds(pos, seensofar, it); 2598 } 2599 Type st = types.supertype(type); 2600 if (st != Type.noType) checkClassBounds(pos, seensofar, st); 2601 } 2602 2603 /** Enter interface into into set. 2604 * If it existed already, issue a "repeated interface" error. 2605 */ 2606 void checkNotRepeated(DiagnosticPosition pos, Type it, Set<Type> its) { 2607 if (its.contains(it)) 2608 log.error(pos, "repeated.interface"); 2609 else { 2610 its.add(it); 2611 } 2612 } 2613 2614/* ************************************************************************* 2615 * Check annotations 2616 **************************************************************************/ 2617 2618 /** 2619 * Recursively validate annotations values 2620 */ 2621 void validateAnnotationTree(JCTree tree) { 2622 class AnnotationValidator extends TreeScanner { 2623 @Override 2624 public void visitAnnotation(JCAnnotation tree) { 2625 if (!tree.type.isErroneous()) { 2626 super.visitAnnotation(tree); 2627 validateAnnotation(tree); 2628 } 2629 } 2630 } 2631 tree.accept(new AnnotationValidator()); 2632 } 2633 2634 /** 2635 * {@literal 2636 * Annotation types are restricted to primitives, String, an 2637 * enum, an annotation, Class, Class<?>, Class<? extends 2638 * Anything>, arrays of the preceding. 2639 * } 2640 */ 2641 void validateAnnotationType(JCTree restype) { 2642 // restype may be null if an error occurred, so don't bother validating it 2643 if (restype != null) { 2644 validateAnnotationType(restype.pos(), restype.type); 2645 } 2646 } 2647 2648 void validateAnnotationType(DiagnosticPosition pos, Type type) { 2649 if (type.isPrimitive()) return; 2650 if (types.isSameType(type, syms.stringType)) return; 2651 if ((type.tsym.flags() & Flags.ENUM) != 0) return; 2652 if ((type.tsym.flags() & Flags.ANNOTATION) != 0) return; 2653 if (types.cvarLowerBound(type).tsym == syms.classType.tsym) return; 2654 if (types.isArray(type) && !types.isArray(types.elemtype(type))) { 2655 validateAnnotationType(pos, types.elemtype(type)); 2656 return; 2657 } 2658 log.error(pos, "invalid.annotation.member.type"); 2659 } 2660 2661 /** 2662 * "It is also a compile-time error if any method declared in an 2663 * annotation type has a signature that is override-equivalent to 2664 * that of any public or protected method declared in class Object 2665 * or in the interface annotation.Annotation." 2666 * 2667 * @jls 9.6 Annotation Types 2668 */ 2669 void validateAnnotationMethod(DiagnosticPosition pos, MethodSymbol m) { 2670 for (Type sup = syms.annotationType; sup.hasTag(CLASS); sup = types.supertype(sup)) { 2671 Scope s = sup.tsym.members(); 2672 for (Symbol sym : s.getSymbolsByName(m.name)) { 2673 if (sym.kind == MTH && 2674 (sym.flags() & (PUBLIC | PROTECTED)) != 0 && 2675 types.overrideEquivalent(m.type, sym.type)) 2676 log.error(pos, "intf.annotation.member.clash", sym, sup); 2677 } 2678 } 2679 } 2680 2681 /** Check the annotations of a symbol. 2682 */ 2683 public void validateAnnotations(List<JCAnnotation> annotations, Symbol s) { 2684 for (JCAnnotation a : annotations) 2685 validateAnnotation(a, s); 2686 } 2687 2688 /** Check the type annotations. 2689 */ 2690 public void validateTypeAnnotations(List<JCAnnotation> annotations, boolean isTypeParameter) { 2691 for (JCAnnotation a : annotations) 2692 validateTypeAnnotation(a, isTypeParameter); 2693 } 2694 2695 /** Check an annotation of a symbol. 2696 */ 2697 private void validateAnnotation(JCAnnotation a, Symbol s) { 2698 validateAnnotationTree(a); 2699 2700 if (!annotationApplicable(a, s)) 2701 log.error(a.pos(), "annotation.type.not.applicable"); 2702 2703 if (a.annotationType.type.tsym == syms.functionalInterfaceType.tsym) { 2704 if (s.kind != TYP) { 2705 log.error(a.pos(), "bad.functional.intf.anno"); 2706 } else if (!s.isInterface() || (s.flags() & ANNOTATION) != 0) { 2707 log.error(a.pos(), "bad.functional.intf.anno.1", diags.fragment("not.a.functional.intf", s)); 2708 } 2709 } 2710 } 2711 2712 public void validateTypeAnnotation(JCAnnotation a, boolean isTypeParameter) { 2713 Assert.checkNonNull(a.type); 2714 validateAnnotationTree(a); 2715 2716 if (a.hasTag(TYPE_ANNOTATION) && 2717 !a.annotationType.type.isErroneous() && 2718 !isTypeAnnotation(a, isTypeParameter)) { 2719 log.error(a.pos(), "annotation.type.not.applicable"); 2720 } 2721 } 2722 2723 /** 2724 * Validate the proposed container 'repeatable' on the 2725 * annotation type symbol 's'. Report errors at position 2726 * 'pos'. 2727 * 2728 * @param s The (annotation)type declaration annotated with a @Repeatable 2729 * @param repeatable the @Repeatable on 's' 2730 * @param pos where to report errors 2731 */ 2732 public void validateRepeatable(TypeSymbol s, Attribute.Compound repeatable, DiagnosticPosition pos) { 2733 Assert.check(types.isSameType(repeatable.type, syms.repeatableType)); 2734 2735 Type t = null; 2736 List<Pair<MethodSymbol,Attribute>> l = repeatable.values; 2737 if (!l.isEmpty()) { 2738 Assert.check(l.head.fst.name == names.value); 2739 t = ((Attribute.Class)l.head.snd).getValue(); 2740 } 2741 2742 if (t == null) { 2743 // errors should already have been reported during Annotate 2744 return; 2745 } 2746 2747 validateValue(t.tsym, s, pos); 2748 validateRetention(t.tsym, s, pos); 2749 validateDocumented(t.tsym, s, pos); 2750 validateInherited(t.tsym, s, pos); 2751 validateTarget(t.tsym, s, pos); 2752 validateDefault(t.tsym, pos); 2753 } 2754 2755 private void validateValue(TypeSymbol container, TypeSymbol contained, DiagnosticPosition pos) { 2756 Symbol sym = container.members().findFirst(names.value); 2757 if (sym != null && sym.kind == MTH) { 2758 MethodSymbol m = (MethodSymbol) sym; 2759 Type ret = m.getReturnType(); 2760 if (!(ret.hasTag(ARRAY) && types.isSameType(((ArrayType)ret).elemtype, contained.type))) { 2761 log.error(pos, "invalid.repeatable.annotation.value.return", 2762 container, ret, types.makeArrayType(contained.type)); 2763 } 2764 } else { 2765 log.error(pos, "invalid.repeatable.annotation.no.value", container); 2766 } 2767 } 2768 2769 private void validateRetention(Symbol container, Symbol contained, DiagnosticPosition pos) { 2770 Attribute.RetentionPolicy containerRetention = types.getRetention(container); 2771 Attribute.RetentionPolicy containedRetention = types.getRetention(contained); 2772 2773 boolean error = false; 2774 switch (containedRetention) { 2775 case RUNTIME: 2776 if (containerRetention != Attribute.RetentionPolicy.RUNTIME) { 2777 error = true; 2778 } 2779 break; 2780 case CLASS: 2781 if (containerRetention == Attribute.RetentionPolicy.SOURCE) { 2782 error = true; 2783 } 2784 } 2785 if (error ) { 2786 log.error(pos, "invalid.repeatable.annotation.retention", 2787 container, containerRetention, 2788 contained, containedRetention); 2789 } 2790 } 2791 2792 private void validateDocumented(Symbol container, Symbol contained, DiagnosticPosition pos) { 2793 if (contained.attribute(syms.documentedType.tsym) != null) { 2794 if (container.attribute(syms.documentedType.tsym) == null) { 2795 log.error(pos, "invalid.repeatable.annotation.not.documented", container, contained); 2796 } 2797 } 2798 } 2799 2800 private void validateInherited(Symbol container, Symbol contained, DiagnosticPosition pos) { 2801 if (contained.attribute(syms.inheritedType.tsym) != null) { 2802 if (container.attribute(syms.inheritedType.tsym) == null) { 2803 log.error(pos, "invalid.repeatable.annotation.not.inherited", container, contained); 2804 } 2805 } 2806 } 2807 2808 private void validateTarget(Symbol container, Symbol contained, DiagnosticPosition pos) { 2809 // The set of targets the container is applicable to must be a subset 2810 // (with respect to annotation target semantics) of the set of targets 2811 // the contained is applicable to. The target sets may be implicit or 2812 // explicit. 2813 2814 Set<Name> containerTargets; 2815 Attribute.Array containerTarget = getAttributeTargetAttribute(container); 2816 if (containerTarget == null) { 2817 containerTargets = getDefaultTargetSet(); 2818 } else { 2819 containerTargets = new HashSet<>(); 2820 for (Attribute app : containerTarget.values) { 2821 if (!(app instanceof Attribute.Enum)) { 2822 continue; // recovery 2823 } 2824 Attribute.Enum e = (Attribute.Enum)app; 2825 containerTargets.add(e.value.name); 2826 } 2827 } 2828 2829 Set<Name> containedTargets; 2830 Attribute.Array containedTarget = getAttributeTargetAttribute(contained); 2831 if (containedTarget == null) { 2832 containedTargets = getDefaultTargetSet(); 2833 } else { 2834 containedTargets = new HashSet<>(); 2835 for (Attribute app : containedTarget.values) { 2836 if (!(app instanceof Attribute.Enum)) { 2837 continue; // recovery 2838 } 2839 Attribute.Enum e = (Attribute.Enum)app; 2840 containedTargets.add(e.value.name); 2841 } 2842 } 2843 2844 if (!isTargetSubsetOf(containerTargets, containedTargets)) { 2845 log.error(pos, "invalid.repeatable.annotation.incompatible.target", container, contained); 2846 } 2847 } 2848 2849 /* get a set of names for the default target */ 2850 private Set<Name> getDefaultTargetSet() { 2851 if (defaultTargets == null) { 2852 Set<Name> targets = new HashSet<>(); 2853 targets.add(names.ANNOTATION_TYPE); 2854 targets.add(names.CONSTRUCTOR); 2855 targets.add(names.FIELD); 2856 targets.add(names.LOCAL_VARIABLE); 2857 targets.add(names.METHOD); 2858 targets.add(names.PACKAGE); 2859 targets.add(names.PARAMETER); 2860 targets.add(names.TYPE); 2861 2862 defaultTargets = java.util.Collections.unmodifiableSet(targets); 2863 } 2864 2865 return defaultTargets; 2866 } 2867 private Set<Name> defaultTargets; 2868 2869 2870 /** Checks that s is a subset of t, with respect to ElementType 2871 * semantics, specifically {ANNOTATION_TYPE} is a subset of {TYPE}, 2872 * and {TYPE_USE} covers the set {ANNOTATION_TYPE, TYPE, TYPE_USE, 2873 * TYPE_PARAMETER}. 2874 */ 2875 private boolean isTargetSubsetOf(Set<Name> s, Set<Name> t) { 2876 // Check that all elements in s are present in t 2877 for (Name n2 : s) { 2878 boolean currentElementOk = false; 2879 for (Name n1 : t) { 2880 if (n1 == n2) { 2881 currentElementOk = true; 2882 break; 2883 } else if (n1 == names.TYPE && n2 == names.ANNOTATION_TYPE) { 2884 currentElementOk = true; 2885 break; 2886 } else if (n1 == names.TYPE_USE && 2887 (n2 == names.TYPE || 2888 n2 == names.ANNOTATION_TYPE || 2889 n2 == names.TYPE_PARAMETER)) { 2890 currentElementOk = true; 2891 break; 2892 } 2893 } 2894 if (!currentElementOk) 2895 return false; 2896 } 2897 return true; 2898 } 2899 2900 private void validateDefault(Symbol container, DiagnosticPosition pos) { 2901 // validate that all other elements of containing type has defaults 2902 Scope scope = container.members(); 2903 for(Symbol elm : scope.getSymbols()) { 2904 if (elm.name != names.value && 2905 elm.kind == MTH && 2906 ((MethodSymbol)elm).defaultValue == null) { 2907 log.error(pos, 2908 "invalid.repeatable.annotation.elem.nondefault", 2909 container, 2910 elm); 2911 } 2912 } 2913 } 2914 2915 /** Is s a method symbol that overrides a method in a superclass? */ 2916 boolean isOverrider(Symbol s) { 2917 if (s.kind != MTH || s.isStatic()) 2918 return false; 2919 MethodSymbol m = (MethodSymbol)s; 2920 TypeSymbol owner = (TypeSymbol)m.owner; 2921 for (Type sup : types.closure(owner.type)) { 2922 if (sup == owner.type) 2923 continue; // skip "this" 2924 Scope scope = sup.tsym.members(); 2925 for (Symbol sym : scope.getSymbolsByName(m.name)) { 2926 if (!sym.isStatic() && m.overrides(sym, owner, types, true)) 2927 return true; 2928 } 2929 } 2930 return false; 2931 } 2932 2933 /** Is the annotation applicable to types? */ 2934 protected boolean isTypeAnnotation(JCAnnotation a, boolean isTypeParameter) { 2935 Attribute.Compound atTarget = 2936 a.annotationType.type.tsym.attribute(syms.annotationTargetType.tsym); 2937 if (atTarget == null) { 2938 // An annotation without @Target is not a type annotation. 2939 return false; 2940 } 2941 2942 Attribute atValue = atTarget.member(names.value); 2943 if (!(atValue instanceof Attribute.Array)) { 2944 return false; // error recovery 2945 } 2946 2947 Attribute.Array arr = (Attribute.Array) atValue; 2948 for (Attribute app : arr.values) { 2949 if (!(app instanceof Attribute.Enum)) { 2950 return false; // recovery 2951 } 2952 Attribute.Enum e = (Attribute.Enum) app; 2953 2954 if (e.value.name == names.TYPE_USE) 2955 return true; 2956 else if (isTypeParameter && e.value.name == names.TYPE_PARAMETER) 2957 return true; 2958 } 2959 return false; 2960 } 2961 2962 /** Is the annotation applicable to the symbol? */ 2963 boolean annotationApplicable(JCAnnotation a, Symbol s) { 2964 Attribute.Array arr = getAttributeTargetAttribute(a.annotationType.type.tsym); 2965 Name[] targets; 2966 2967 if (arr == null) { 2968 targets = defaultTargetMetaInfo(a, s); 2969 } else { 2970 // TODO: can we optimize this? 2971 targets = new Name[arr.values.length]; 2972 for (int i=0; i<arr.values.length; ++i) { 2973 Attribute app = arr.values[i]; 2974 if (!(app instanceof Attribute.Enum)) { 2975 return true; // recovery 2976 } 2977 Attribute.Enum e = (Attribute.Enum) app; 2978 targets[i] = e.value.name; 2979 } 2980 } 2981 for (Name target : targets) { 2982 if (target == names.TYPE) 2983 { if (s.kind == TYP) return true; } 2984 else if (target == names.FIELD) 2985 { if (s.kind == VAR && s.owner.kind != MTH) return true; } 2986 else if (target == names.METHOD) 2987 { if (s.kind == MTH && !s.isConstructor()) return true; } 2988 else if (target == names.PARAMETER) 2989 { if (s.kind == VAR && s.owner.kind == MTH && 2990 (s.flags() & PARAMETER) != 0) 2991 return true; 2992 } 2993 else if (target == names.CONSTRUCTOR) 2994 { if (s.kind == MTH && s.isConstructor()) return true; } 2995 else if (target == names.LOCAL_VARIABLE) 2996 { if (s.kind == VAR && s.owner.kind == MTH && 2997 (s.flags() & PARAMETER) == 0) 2998 return true; 2999 } 3000 else if (target == names.ANNOTATION_TYPE) 3001 { if (s.kind == TYP && (s.flags() & ANNOTATION) != 0) 3002 return true; 3003 } 3004 else if (target == names.PACKAGE) 3005 { if (s.kind == PCK) return true; } 3006 else if (target == names.TYPE_USE) 3007 { if (s.kind == TYP || s.kind == VAR || 3008 (s.kind == MTH && !s.isConstructor() && 3009 !s.type.getReturnType().hasTag(VOID)) || 3010 (s.kind == MTH && s.isConstructor())) 3011 return true; 3012 } 3013 else if (target == names.TYPE_PARAMETER) 3014 { if (s.kind == TYP && s.type.hasTag(TYPEVAR)) 3015 return true; 3016 } 3017 else 3018 return true; // recovery 3019 } 3020 return false; 3021 } 3022 3023 3024 Attribute.Array getAttributeTargetAttribute(Symbol s) { 3025 Attribute.Compound atTarget = 3026 s.attribute(syms.annotationTargetType.tsym); 3027 if (atTarget == null) return null; // ok, is applicable 3028 Attribute atValue = atTarget.member(names.value); 3029 if (!(atValue instanceof Attribute.Array)) return null; // error recovery 3030 return (Attribute.Array) atValue; 3031 } 3032 3033 private final Name[] dfltTargetMeta; 3034 private Name[] defaultTargetMetaInfo(JCAnnotation a, Symbol s) { 3035 return dfltTargetMeta; 3036 } 3037 3038 /** Check an annotation value. 3039 * 3040 * @param a The annotation tree to check 3041 * @return true if this annotation tree is valid, otherwise false 3042 */ 3043 public boolean validateAnnotationDeferErrors(JCAnnotation a) { 3044 boolean res = false; 3045 final Log.DiagnosticHandler diagHandler = new Log.DiscardDiagnosticHandler(log); 3046 try { 3047 res = validateAnnotation(a); 3048 } finally { 3049 log.popDiagnosticHandler(diagHandler); 3050 } 3051 return res; 3052 } 3053 3054 private boolean validateAnnotation(JCAnnotation a) { 3055 boolean isValid = true; 3056 // collect an inventory of the annotation elements 3057 Set<MethodSymbol> members = new LinkedHashSet<>(); 3058 for (Symbol sym : a.annotationType.type.tsym.members().getSymbols(NON_RECURSIVE)) 3059 if (sym.kind == MTH && sym.name != names.clinit && 3060 (sym.flags() & SYNTHETIC) == 0) 3061 members.add((MethodSymbol) sym); 3062 3063 // remove the ones that are assigned values 3064 for (JCTree arg : a.args) { 3065 if (!arg.hasTag(ASSIGN)) continue; // recovery 3066 JCAssign assign = (JCAssign) arg; 3067 Symbol m = TreeInfo.symbol(assign.lhs); 3068 if (m == null || m.type.isErroneous()) continue; 3069 if (!members.remove(m)) { 3070 isValid = false; 3071 log.error(assign.lhs.pos(), "duplicate.annotation.member.value", 3072 m.name, a.type); 3073 } 3074 } 3075 3076 // all the remaining ones better have default values 3077 List<Name> missingDefaults = List.nil(); 3078 for (MethodSymbol m : members) { 3079 if (m.defaultValue == null && !m.type.isErroneous()) { 3080 missingDefaults = missingDefaults.append(m.name); 3081 } 3082 } 3083 missingDefaults = missingDefaults.reverse(); 3084 if (missingDefaults.nonEmpty()) { 3085 isValid = false; 3086 String key = (missingDefaults.size() > 1) 3087 ? "annotation.missing.default.value.1" 3088 : "annotation.missing.default.value"; 3089 log.error(a.pos(), key, a.type, missingDefaults); 3090 } 3091 3092 // special case: java.lang.annotation.Target must not have 3093 // repeated values in its value member 3094 if (a.annotationType.type.tsym != syms.annotationTargetType.tsym || 3095 a.args.tail == null) 3096 return isValid; 3097 3098 if (!a.args.head.hasTag(ASSIGN)) return false; // error recovery 3099 JCAssign assign = (JCAssign) a.args.head; 3100 Symbol m = TreeInfo.symbol(assign.lhs); 3101 if (m.name != names.value) return false; 3102 JCTree rhs = assign.rhs; 3103 if (!rhs.hasTag(NEWARRAY)) return false; 3104 JCNewArray na = (JCNewArray) rhs; 3105 Set<Symbol> targets = new HashSet<>(); 3106 for (JCTree elem : na.elems) { 3107 if (!targets.add(TreeInfo.symbol(elem))) { 3108 isValid = false; 3109 log.error(elem.pos(), "repeated.annotation.target"); 3110 } 3111 } 3112 return isValid; 3113 } 3114 3115 void checkDeprecatedAnnotation(DiagnosticPosition pos, Symbol s) { 3116 if (lint.isEnabled(LintCategory.DEP_ANN) && 3117 (s.flags() & DEPRECATED) != 0 && 3118 !syms.deprecatedType.isErroneous() && 3119 s.attribute(syms.deprecatedType.tsym) == null) { 3120 log.warning(LintCategory.DEP_ANN, 3121 pos, "missing.deprecated.annotation"); 3122 } 3123 } 3124 3125 void checkDeprecated(final DiagnosticPosition pos, final Symbol other, final Symbol s) { 3126 if ((s.flags() & DEPRECATED) != 0 && 3127 (other.flags() & DEPRECATED) == 0 && 3128 s.outermostClass() != other.outermostClass()) { 3129 deferredLintHandler.report(new DeferredLintHandler.LintLogger() { 3130 @Override 3131 public void report() { 3132 warnDeprecated(pos, s); 3133 } 3134 }); 3135 } 3136 } 3137 3138 void checkSunAPI(final DiagnosticPosition pos, final Symbol s) { 3139 if ((s.flags() & PROPRIETARY) != 0) { 3140 deferredLintHandler.report(new DeferredLintHandler.LintLogger() { 3141 public void report() { 3142 if (enableSunApiLintControl) 3143 warnSunApi(pos, "sun.proprietary", s); 3144 else 3145 log.mandatoryWarning(pos, "sun.proprietary", s); 3146 } 3147 }); 3148 } 3149 } 3150 3151 void checkProfile(final DiagnosticPosition pos, final Symbol s) { 3152 if (profile != Profile.DEFAULT && (s.flags() & NOT_IN_PROFILE) != 0) { 3153 log.error(pos, "not.in.profile", s, profile); 3154 } 3155 } 3156 3157/* ************************************************************************* 3158 * Check for recursive annotation elements. 3159 **************************************************************************/ 3160 3161 /** Check for cycles in the graph of annotation elements. 3162 */ 3163 void checkNonCyclicElements(JCClassDecl tree) { 3164 if ((tree.sym.flags_field & ANNOTATION) == 0) return; 3165 Assert.check((tree.sym.flags_field & LOCKED) == 0); 3166 try { 3167 tree.sym.flags_field |= LOCKED; 3168 for (JCTree def : tree.defs) { 3169 if (!def.hasTag(METHODDEF)) continue; 3170 JCMethodDecl meth = (JCMethodDecl)def; 3171 checkAnnotationResType(meth.pos(), meth.restype.type); 3172 } 3173 } finally { 3174 tree.sym.flags_field &= ~LOCKED; 3175 tree.sym.flags_field |= ACYCLIC_ANN; 3176 } 3177 } 3178 3179 void checkNonCyclicElementsInternal(DiagnosticPosition pos, TypeSymbol tsym) { 3180 if ((tsym.flags_field & ACYCLIC_ANN) != 0) 3181 return; 3182 if ((tsym.flags_field & LOCKED) != 0) { 3183 log.error(pos, "cyclic.annotation.element"); 3184 return; 3185 } 3186 try { 3187 tsym.flags_field |= LOCKED; 3188 for (Symbol s : tsym.members().getSymbols(NON_RECURSIVE)) { 3189 if (s.kind != MTH) 3190 continue; 3191 checkAnnotationResType(pos, ((MethodSymbol)s).type.getReturnType()); 3192 } 3193 } finally { 3194 tsym.flags_field &= ~LOCKED; 3195 tsym.flags_field |= ACYCLIC_ANN; 3196 } 3197 } 3198 3199 void checkAnnotationResType(DiagnosticPosition pos, Type type) { 3200 switch (type.getTag()) { 3201 case CLASS: 3202 if ((type.tsym.flags() & ANNOTATION) != 0) 3203 checkNonCyclicElementsInternal(pos, type.tsym); 3204 break; 3205 case ARRAY: 3206 checkAnnotationResType(pos, types.elemtype(type)); 3207 break; 3208 default: 3209 break; // int etc 3210 } 3211 } 3212 3213/* ************************************************************************* 3214 * Check for cycles in the constructor call graph. 3215 **************************************************************************/ 3216 3217 /** Check for cycles in the graph of constructors calling other 3218 * constructors. 3219 */ 3220 void checkCyclicConstructors(JCClassDecl tree) { 3221 Map<Symbol,Symbol> callMap = new HashMap<>(); 3222 3223 // enter each constructor this-call into the map 3224 for (List<JCTree> l = tree.defs; l.nonEmpty(); l = l.tail) { 3225 JCMethodInvocation app = TreeInfo.firstConstructorCall(l.head); 3226 if (app == null) continue; 3227 JCMethodDecl meth = (JCMethodDecl) l.head; 3228 if (TreeInfo.name(app.meth) == names._this) { 3229 callMap.put(meth.sym, TreeInfo.symbol(app.meth)); 3230 } else { 3231 meth.sym.flags_field |= ACYCLIC; 3232 } 3233 } 3234 3235 // Check for cycles in the map 3236 Symbol[] ctors = new Symbol[0]; 3237 ctors = callMap.keySet().toArray(ctors); 3238 for (Symbol caller : ctors) { 3239 checkCyclicConstructor(tree, caller, callMap); 3240 } 3241 } 3242 3243 /** Look in the map to see if the given constructor is part of a 3244 * call cycle. 3245 */ 3246 private void checkCyclicConstructor(JCClassDecl tree, Symbol ctor, 3247 Map<Symbol,Symbol> callMap) { 3248 if (ctor != null && (ctor.flags_field & ACYCLIC) == 0) { 3249 if ((ctor.flags_field & LOCKED) != 0) { 3250 log.error(TreeInfo.diagnosticPositionFor(ctor, tree), 3251 "recursive.ctor.invocation"); 3252 } else { 3253 ctor.flags_field |= LOCKED; 3254 checkCyclicConstructor(tree, callMap.remove(ctor), callMap); 3255 ctor.flags_field &= ~LOCKED; 3256 } 3257 ctor.flags_field |= ACYCLIC; 3258 } 3259 } 3260 3261/* ************************************************************************* 3262 * Miscellaneous 3263 **************************************************************************/ 3264 3265 /** 3266 * Check for division by integer constant zero 3267 * @param pos Position for error reporting. 3268 * @param operator The operator for the expression 3269 * @param operand The right hand operand for the expression 3270 */ 3271 void checkDivZero(final DiagnosticPosition pos, Symbol operator, Type operand) { 3272 if (operand.constValue() != null 3273 && operand.getTag().isSubRangeOf(LONG) 3274 && ((Number) (operand.constValue())).longValue() == 0) { 3275 int opc = ((OperatorSymbol)operator).opcode; 3276 if (opc == ByteCodes.idiv || opc == ByteCodes.imod 3277 || opc == ByteCodes.ldiv || opc == ByteCodes.lmod) { 3278 deferredLintHandler.report(new DeferredLintHandler.LintLogger() { 3279 @Override 3280 public void report() { 3281 warnDivZero(pos); 3282 } 3283 }); 3284 } 3285 } 3286 } 3287 3288 /** 3289 * Check for empty statements after if 3290 */ 3291 void checkEmptyIf(JCIf tree) { 3292 if (tree.thenpart.hasTag(SKIP) && tree.elsepart == null && 3293 lint.isEnabled(LintCategory.EMPTY)) 3294 log.warning(LintCategory.EMPTY, tree.thenpart.pos(), "empty.if"); 3295 } 3296 3297 /** Check that symbol is unique in given scope. 3298 * @param pos Position for error reporting. 3299 * @param sym The symbol. 3300 * @param s The scope. 3301 */ 3302 boolean checkUnique(DiagnosticPosition pos, Symbol sym, Scope s) { 3303 if (sym.type.isErroneous()) 3304 return true; 3305 if (sym.owner.name == names.any) return false; 3306 for (Symbol byName : s.getSymbolsByName(sym.name, NON_RECURSIVE)) { 3307 if (sym != byName && 3308 (byName.flags() & CLASH) == 0 && 3309 sym.kind == byName.kind && 3310 sym.name != names.error && 3311 (sym.kind != MTH || 3312 types.hasSameArgs(sym.type, byName.type) || 3313 types.hasSameArgs(types.erasure(sym.type), types.erasure(byName.type)))) { 3314 if ((sym.flags() & VARARGS) != (byName.flags() & VARARGS)) { 3315 varargsDuplicateError(pos, sym, byName); 3316 return true; 3317 } else if (sym.kind == MTH && !types.hasSameArgs(sym.type, byName.type, false)) { 3318 duplicateErasureError(pos, sym, byName); 3319 sym.flags_field |= CLASH; 3320 return true; 3321 } else { 3322 duplicateError(pos, byName); 3323 return false; 3324 } 3325 } 3326 } 3327 return true; 3328 } 3329 3330 /** Report duplicate declaration error. 3331 */ 3332 void duplicateErasureError(DiagnosticPosition pos, Symbol sym1, Symbol sym2) { 3333 if (!sym1.type.isErroneous() && !sym2.type.isErroneous()) { 3334 log.error(pos, "name.clash.same.erasure", sym1, sym2); 3335 } 3336 } 3337 3338 /**Check that types imported through the ordinary imports don't clash with types imported 3339 * by other (static or ordinary) imports. Note that two static imports may import two clashing 3340 * types without an error on the imports. 3341 * @param toplevel The toplevel tree for which the test should be performed. 3342 */ 3343 void checkImportsUnique(JCCompilationUnit toplevel) { 3344 WriteableScope ordinallyImportedSoFar = WriteableScope.create(toplevel.packge); 3345 WriteableScope staticallyImportedSoFar = WriteableScope.create(toplevel.packge); 3346 WriteableScope topLevelScope = toplevel.toplevelScope; 3347 3348 for (JCTree def : toplevel.defs) { 3349 if (!def.hasTag(IMPORT)) 3350 continue; 3351 3352 JCImport imp = (JCImport) def; 3353 3354 if (imp.importScope == null) 3355 continue; 3356 3357 for (Symbol sym : imp.importScope.getSymbols(sym -> sym.kind == TYP)) { 3358 if (imp.isStatic()) { 3359 checkUniqueImport(imp.pos(), ordinallyImportedSoFar, staticallyImportedSoFar, topLevelScope, sym, true); 3360 staticallyImportedSoFar.enter(sym); 3361 } else { 3362 checkUniqueImport(imp.pos(), ordinallyImportedSoFar, staticallyImportedSoFar, topLevelScope, sym, false); 3363 ordinallyImportedSoFar.enter(sym); 3364 } 3365 } 3366 3367 imp.importScope = null; 3368 } 3369 } 3370 3371 /** Check that single-type import is not already imported or top-level defined, 3372 * but make an exception for two single-type imports which denote the same type. 3373 * @param pos Position for error reporting. 3374 * @param ordinallyImportedSoFar A Scope containing types imported so far through 3375 * ordinary imports. 3376 * @param staticallyImportedSoFar A Scope containing types imported so far through 3377 * static imports. 3378 * @param topLevelScope The current file's top-level Scope 3379 * @param sym The symbol. 3380 * @param staticImport Whether or not this was a static import 3381 */ 3382 private boolean checkUniqueImport(DiagnosticPosition pos, Scope ordinallyImportedSoFar, 3383 Scope staticallyImportedSoFar, Scope topLevelScope, 3384 Symbol sym, boolean staticImport) { 3385 Filter<Symbol> duplicates = candidate -> candidate != sym && !candidate.type.isErroneous(); 3386 Symbol clashing = ordinallyImportedSoFar.findFirst(sym.name, duplicates); 3387 if (clashing == null && !staticImport) { 3388 clashing = staticallyImportedSoFar.findFirst(sym.name, duplicates); 3389 } 3390 if (clashing != null) { 3391 if (staticImport) 3392 log.error(pos, "already.defined.static.single.import", clashing); 3393 else 3394 log.error(pos, "already.defined.single.import", clashing); 3395 return false; 3396 } 3397 clashing = topLevelScope.findFirst(sym.name, duplicates); 3398 if (clashing != null) { 3399 log.error(pos, "already.defined.this.unit", clashing); 3400 return false; 3401 } 3402 return true; 3403 } 3404 3405 /** Check that a qualified name is in canonical form (for import decls). 3406 */ 3407 public void checkCanonical(JCTree tree) { 3408 if (!isCanonical(tree)) 3409 log.error(tree.pos(), "import.requires.canonical", 3410 TreeInfo.symbol(tree)); 3411 } 3412 // where 3413 private boolean isCanonical(JCTree tree) { 3414 while (tree.hasTag(SELECT)) { 3415 JCFieldAccess s = (JCFieldAccess) tree; 3416 if (s.sym.owner != TreeInfo.symbol(s.selected)) 3417 return false; 3418 tree = s.selected; 3419 } 3420 return true; 3421 } 3422 3423 /** Check that an auxiliary class is not accessed from any other file than its own. 3424 */ 3425 void checkForBadAuxiliaryClassAccess(DiagnosticPosition pos, Env<AttrContext> env, ClassSymbol c) { 3426 if (lint.isEnabled(Lint.LintCategory.AUXILIARYCLASS) && 3427 (c.flags() & AUXILIARY) != 0 && 3428 rs.isAccessible(env, c) && 3429 !fileManager.isSameFile(c.sourcefile, env.toplevel.sourcefile)) 3430 { 3431 log.warning(pos, "auxiliary.class.accessed.from.outside.of.its.source.file", 3432 c, c.sourcefile); 3433 } 3434 } 3435 3436 private class ConversionWarner extends Warner { 3437 final String uncheckedKey; 3438 final Type found; 3439 final Type expected; 3440 public ConversionWarner(DiagnosticPosition pos, String uncheckedKey, Type found, Type expected) { 3441 super(pos); 3442 this.uncheckedKey = uncheckedKey; 3443 this.found = found; 3444 this.expected = expected; 3445 } 3446 3447 @Override 3448 public void warn(LintCategory lint) { 3449 boolean warned = this.warned; 3450 super.warn(lint); 3451 if (warned) return; // suppress redundant diagnostics 3452 switch (lint) { 3453 case UNCHECKED: 3454 Check.this.warnUnchecked(pos(), "prob.found.req", diags.fragment(uncheckedKey), found, expected); 3455 break; 3456 case VARARGS: 3457 if (method != null && 3458 method.attribute(syms.trustMeType.tsym) != null && 3459 isTrustMeAllowedOnMethod(method) && 3460 !types.isReifiable(method.type.getParameterTypes().last())) { 3461 Check.this.warnUnsafeVararg(pos(), "varargs.unsafe.use.varargs.param", method.params.last()); 3462 } 3463 break; 3464 default: 3465 throw new AssertionError("Unexpected lint: " + lint); 3466 } 3467 } 3468 } 3469 3470 public Warner castWarner(DiagnosticPosition pos, Type found, Type expected) { 3471 return new ConversionWarner(pos, "unchecked.cast.to.type", found, expected); 3472 } 3473 3474 public Warner convertWarner(DiagnosticPosition pos, Type found, Type expected) { 3475 return new ConversionWarner(pos, "unchecked.assign", found, expected); 3476 } 3477 3478 public void checkFunctionalInterface(JCClassDecl tree, ClassSymbol cs) { 3479 Compound functionalType = cs.attribute(syms.functionalInterfaceType.tsym); 3480 3481 if (functionalType != null) { 3482 try { 3483 types.findDescriptorSymbol((TypeSymbol)cs); 3484 } catch (Types.FunctionDescriptorLookupError ex) { 3485 DiagnosticPosition pos = tree.pos(); 3486 for (JCAnnotation a : tree.getModifiers().annotations) { 3487 if (a.annotationType.type.tsym == syms.functionalInterfaceType.tsym) { 3488 pos = a.pos(); 3489 break; 3490 } 3491 } 3492 log.error(pos, "bad.functional.intf.anno.1", ex.getDiagnostic()); 3493 } 3494 } 3495 } 3496 3497 public void checkImportsResolvable(final JCCompilationUnit toplevel) { 3498 for (final JCImport imp : toplevel.getImports()) { 3499 if (!imp.staticImport || !imp.qualid.hasTag(SELECT)) 3500 continue; 3501 final JCFieldAccess select = (JCFieldAccess) imp.qualid; 3502 final Symbol origin; 3503 if (select.name == names.asterisk || (origin = TreeInfo.symbol(select.selected)) == null || origin.kind != TYP) 3504 continue; 3505 3506 TypeSymbol site = (TypeSymbol) TreeInfo.symbol(select.selected); 3507 if (!checkTypeContainsImportableElement(site, site, toplevel.packge, select.name, new HashSet<Symbol>())) { 3508 log.error(imp.pos(), "cant.resolve.location", 3509 KindName.STATIC, 3510 select.name, List.<Type>nil(), List.<Type>nil(), 3511 Kinds.typeKindName(TreeInfo.symbol(select.selected).type), 3512 TreeInfo.symbol(select.selected).type); 3513 } 3514 } 3515 } 3516 3517 private boolean checkTypeContainsImportableElement(TypeSymbol tsym, TypeSymbol origin, PackageSymbol packge, Name name, Set<Symbol> processed) { 3518 if (tsym == null || !processed.add(tsym)) 3519 return false; 3520 3521 // also search through inherited names 3522 if (checkTypeContainsImportableElement(types.supertype(tsym.type).tsym, origin, packge, name, processed)) 3523 return true; 3524 3525 for (Type t : types.interfaces(tsym.type)) 3526 if (checkTypeContainsImportableElement(t.tsym, origin, packge, name, processed)) 3527 return true; 3528 3529 for (Symbol sym : tsym.members().getSymbolsByName(name)) { 3530 if (sym.isStatic() && 3531 importAccessible(sym, packge) && 3532 sym.isMemberOf(origin, types)) { 3533 return true; 3534 } 3535 } 3536 3537 return false; 3538 } 3539 3540 // is the sym accessible everywhere in packge? 3541 public boolean importAccessible(Symbol sym, PackageSymbol packge) { 3542 try { 3543 int flags = (int)(sym.flags() & AccessFlags); 3544 switch (flags) { 3545 default: 3546 case PUBLIC: 3547 return true; 3548 case PRIVATE: 3549 return false; 3550 case 0: 3551 case PROTECTED: 3552 return sym.packge() == packge; 3553 } 3554 } catch (ClassFinder.BadClassFile err) { 3555 throw err; 3556 } catch (CompletionFailure ex) { 3557 return false; 3558 } 3559 } 3560 3561} 3562