Check.java revision 2897:524255b0bec0
1215125Sed/* 2215125Sed * Copyright (c) 1999, 2015, Oracle and/or its affiliates. All rights reserved. 3215125Sed * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. 4215125Sed * 5215125Sed * This code is free software; you can redistribute it and/or modify it 6215125Sed * under the terms of the GNU General Public License version 2 only, as 7215125Sed * published by the Free Software Foundation. Oracle designates this 8215125Sed * particular file as subject to the "Classpath" exception as provided 9215129Sed * by Oracle in the LICENSE file that accompanied this code. 10215125Sed * 11215125Sed * This code is distributed in the hope that it will be useful, but WITHOUT 12215125Sed * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or 13215125Sed * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License 14215125Sed * version 2 for more details (a copy is included in the LICENSE file that 15215125Sed * accompanied this code). 16215125Sed * 17215125Sed * You should have received a copy of the GNU General Public License version 18215125Sed * 2 along with this work; if not, write to the Free Software Foundation, 19215125Sed * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. 20215125Sed * 21215125Sed * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA 22215125Sed * or visit www.oracle.com if you need additional information or have any 23215125Sed * questions. 24215125Sed */ 25215125Sed 26215125Sedpackage com.sun.tools.javac.comp; 27215125Sed 28215125Sedimport java.util.*; 29215125Sed 30215125Sedimport javax.tools.JavaFileManager; 31215125Sed 32215125Sedimport com.sun.tools.javac.code.*; 33215125Sedimport com.sun.tools.javac.code.Attribute.Compound; 34215125Sedimport com.sun.tools.javac.comp.Annotate.AnnotationTypeMetadata; 35215125Sedimport com.sun.tools.javac.jvm.*; 36215125Sedimport com.sun.tools.javac.resources.CompilerProperties.Errors; 37215125Sedimport com.sun.tools.javac.resources.CompilerProperties.Fragments; 38215125Sedimport com.sun.tools.javac.tree.*; 39215125Sedimport com.sun.tools.javac.util.*; 40215125Sedimport com.sun.tools.javac.util.JCDiagnostic.DiagnosticPosition; 41215125Sedimport com.sun.tools.javac.util.List; 42215125Sed 43215125Sedimport com.sun.tools.javac.code.Lint; 44222656Sedimport com.sun.tools.javac.code.Lint.LintCategory; 45222656Sedimport com.sun.tools.javac.code.Scope.CompoundScope; 46215125Sedimport com.sun.tools.javac.code.Scope.NamedImportScope; 47215125Sedimport com.sun.tools.javac.code.Scope.WriteableScope; 48215125Sedimport com.sun.tools.javac.code.Type.*; 49215125Sedimport com.sun.tools.javac.code.Symbol.*; 50215125Sedimport com.sun.tools.javac.comp.DeferredAttr.DeferredAttrContext; 51215125Sedimport com.sun.tools.javac.comp.Infer.InferenceContext; 52215125Sedimport com.sun.tools.javac.comp.Infer.FreeTypeListener; 53215125Sedimport com.sun.tools.javac.tree.JCTree.*; 54215125Sedimport com.sun.tools.javac.tree.JCTree.JCPolyExpression.*; 55215125Sed 56215125Sedimport static com.sun.tools.javac.code.Flags.*; 57215125Sedimport static com.sun.tools.javac.code.Flags.ANNOTATION; 58215125Sedimport static com.sun.tools.javac.code.Flags.SYNCHRONIZED; 59215125Sedimport static com.sun.tools.javac.code.Kinds.*; 60215125Sedimport static com.sun.tools.javac.code.Kinds.Kind.*; 61215125Sedimport static com.sun.tools.javac.code.Scope.LookupKind.NON_RECURSIVE; 62215125Sedimport static com.sun.tools.javac.code.TypeTag.*; 63215125Sedimport static com.sun.tools.javac.code.TypeTag.WILDCARD; 64215125Sed 65215125Sedimport static com.sun.tools.javac.tree.JCTree.Tag.*; 66215125Sed 67215125Sed/** Type checking helper class for the attribution phase. 68215125Sed * 69215125Sed * <p><b>This is NOT part of any supported API. 70215125Sed * If you write code that depends on this, you do so at your own risk. 71215125Sed * This code and its internal interfaces are subject to change or 72215125Sed * deletion without notice.</b> 73215125Sed */ 74215125Sedpublic class Check { 75215125Sed protected static final Context.Key<Check> checkKey = new Context.Key<>(); 76215125Sed 77215125Sed private final Names names; 78215125Sed private final Log log; 79215125Sed private final Resolve rs; 80215125Sed private final Symtab syms; 81215125Sed private final Enter enter; 82215125Sed private final DeferredAttr deferredAttr; 83215125Sed private final Infer infer; 84215125Sed private final Types types; 85215125Sed private final TypeAnnotations typeAnnotations; 86215125Sed private final JCDiagnostic.Factory diags; 87215125Sed private boolean warnOnSyntheticConflicts; 88215125Sed private boolean suppressAbortOnBadClassFile; 89215125Sed private boolean enableSunApiLintControl; 90215125Sed private final JavaFileManager fileManager; 91215125Sed private final Source source; 92215125Sed private final Profile profile; 93215125Sed private final boolean warnOnAccessToSensitiveMembers; 94215125Sed 95215125Sed // The set of lint options currently in effect. It is initialized 96215125Sed // from the context, and then is set/reset as needed by Attr as it 97215125Sed // visits all the various parts of the trees during attribution. 98215125Sed private Lint lint; 99215125Sed 100215125Sed // The method being analyzed in Attr - it is set/reset as needed by 101215125Sed // Attr as it visits new method declarations. 102215125Sed private MethodSymbol method; 103215125Sed 104215125Sed public static Check instance(Context context) { 105215125Sed Check instance = context.get(checkKey); 106215125Sed if (instance == null) 107215125Sed instance = new Check(context); 108215125Sed return instance; 109215125Sed } 110215125Sed 111215125Sed protected Check(Context context) { 112215125Sed context.put(checkKey, this); 113215125Sed 114215125Sed names = Names.instance(context); 115215125Sed dfltTargetMeta = new Name[] { names.PACKAGE, names.TYPE, 116215125Sed names.FIELD, names.METHOD, names.CONSTRUCTOR, 117215125Sed names.ANNOTATION_TYPE, names.LOCAL_VARIABLE, names.PARAMETER}; 118215125Sed log = Log.instance(context); 119222656Sed rs = Resolve.instance(context); 120215125Sed syms = Symtab.instance(context); 121215125Sed enter = Enter.instance(context); 122215125Sed deferredAttr = DeferredAttr.instance(context); 123215125Sed infer = Infer.instance(context); 124215125Sed types = Types.instance(context); 125215125Sed typeAnnotations = TypeAnnotations.instance(context); 126215125Sed diags = JCDiagnostic.Factory.instance(context); 127215125Sed Options options = Options.instance(context); 128215125Sed lint = Lint.instance(context); 129215125Sed fileManager = context.get(JavaFileManager.class); 130215125Sed 131215125Sed source = Source.instance(context); 132215125Sed allowSimplifiedVarargs = source.allowSimplifiedVarargs(); 133215125Sed allowDefaultMethods = source.allowDefaultMethods(); 134215125Sed allowStrictMethodClashCheck = source.allowStrictMethodClashCheck(); 135215125Sed allowPrivateSafeVarargs = source.allowPrivateSafeVarargs(); 136215125Sed allowDiamondWithAnonymousClassCreation = source.allowDiamondWithAnonymousClassCreation(); 137215125Sed complexInference = options.isSet("complexinference"); 138215125Sed warnOnSyntheticConflicts = options.isSet("warnOnSyntheticConflicts"); 139215125Sed suppressAbortOnBadClassFile = options.isSet("suppressAbortOnBadClassFile"); 140222656Sed enableSunApiLintControl = options.isSet("enableSunApiLintControl"); 141222656Sed warnOnAccessToSensitiveMembers = options.isSet("warnOnAccessToSensitiveMembers"); 142215125Sed 143215125Sed Target target = Target.instance(context); 144215125Sed syntheticNameChar = target.syntheticNameChar(); 145215125Sed 146215125Sed profile = Profile.instance(context); 147215125Sed 148215125Sed boolean verboseDeprecated = lint.isEnabled(LintCategory.DEPRECATION); 149215125Sed boolean verboseUnchecked = lint.isEnabled(LintCategory.UNCHECKED); 150215125Sed boolean verboseSunApi = lint.isEnabled(LintCategory.SUNAPI); 151215125Sed boolean enforceMandatoryWarnings = true; 152215125Sed 153215125Sed deprecationHandler = new MandatoryWarningHandler(log, verboseDeprecated, 154215125Sed enforceMandatoryWarnings, "deprecated", LintCategory.DEPRECATION); 155236014Smarius uncheckedHandler = new MandatoryWarningHandler(log, verboseUnchecked, 156215185Sed enforceMandatoryWarnings, "unchecked", LintCategory.UNCHECKED); 157215125Sed sunApiHandler = new MandatoryWarningHandler(log, verboseSunApi, 158215185Sed enforceMandatoryWarnings, "sunapi", null); 159215185Sed 160215125Sed deferredLintHandler = DeferredLintHandler.instance(context); 161215185Sed } 162215125Sed 163215125Sed /** Switch: simplified varargs enabled? 164217393Skib */ 165217393Skib boolean allowSimplifiedVarargs; 166217101Skib 167217102Skib /** Switch: default methods enabled? 168217101Skib */ 169217101Skib boolean allowDefaultMethods; 170217101Skib 171215125Sed /** Switch: should unrelated return types trigger a method clash? 172 */ 173 boolean allowStrictMethodClashCheck; 174 175 /** Switch: can the @SafeVarargs annotation be applied to private methods? 176 */ 177 boolean allowPrivateSafeVarargs; 178 179 /** Switch: can diamond inference be used in anonymous instance creation ? 180 */ 181 boolean allowDiamondWithAnonymousClassCreation; 182 183 /** Switch: -complexinference option set? 184 */ 185 boolean complexInference; 186 187 /** Character for synthetic names 188 */ 189 char syntheticNameChar; 190 191 /** A table mapping flat names of all compiled classes in this run to their 192 * symbols; maintained from outside. 193 */ 194 public Map<Name,ClassSymbol> compiled = new HashMap<>(); 195 196 /** A handler for messages about deprecated usage. 197 */ 198 private MandatoryWarningHandler deprecationHandler; 199 200 /** A handler for messages about unchecked or unsafe usage. 201 */ 202 private MandatoryWarningHandler uncheckedHandler; 203 204 /** A handler for messages about using proprietary API. 205 */ 206 private MandatoryWarningHandler sunApiHandler; 207 208 /** A handler for deferred lint warnings. 209 */ 210 private DeferredLintHandler deferredLintHandler; 211 212/* ************************************************************************* 213 * Errors and Warnings 214 **************************************************************************/ 215 216 Lint setLint(Lint newLint) { 217 Lint prev = lint; 218 lint = newLint; 219 return prev; 220 } 221 222 MethodSymbol setMethod(MethodSymbol newMethod) { 223 MethodSymbol prev = method; 224 method = newMethod; 225 return prev; 226 } 227 228 /** Warn about deprecated symbol. 229 * @param pos Position to be used for error reporting. 230 * @param sym The deprecated symbol. 231 */ 232 void warnDeprecated(DiagnosticPosition pos, Symbol sym) { 233 if (!lint.isSuppressed(LintCategory.DEPRECATION)) 234 deprecationHandler.report(pos, "has.been.deprecated", sym, sym.location()); 235 } 236 237 /** Warn about unchecked operation. 238 * @param pos Position to be used for error reporting. 239 * @param msg A string describing the problem. 240 */ 241 public void warnUnchecked(DiagnosticPosition pos, String msg, Object... args) { 242 if (!lint.isSuppressed(LintCategory.UNCHECKED)) 243 uncheckedHandler.report(pos, msg, args); 244 } 245 246 /** Warn about unsafe vararg method decl. 247 * @param pos Position to be used for error reporting. 248 */ 249 void warnUnsafeVararg(DiagnosticPosition pos, String key, Object... args) { 250 if (lint.isEnabled(LintCategory.VARARGS) && allowSimplifiedVarargs) 251 log.warning(LintCategory.VARARGS, pos, key, args); 252 } 253 254 /** Warn about using proprietary API. 255 * @param pos Position to be used for error reporting. 256 * @param msg A string describing the problem. 257 */ 258 public void warnSunApi(DiagnosticPosition pos, String msg, Object... args) { 259 if (!lint.isSuppressed(LintCategory.SUNAPI)) 260 sunApiHandler.report(pos, msg, args); 261 } 262 263 public void warnStatic(DiagnosticPosition pos, String msg, Object... args) { 264 if (lint.isEnabled(LintCategory.STATIC)) 265 log.warning(LintCategory.STATIC, pos, msg, args); 266 } 267 268 /** Warn about division by integer constant zero. 269 * @param pos Position to be used for error reporting. 270 */ 271 void warnDivZero(DiagnosticPosition pos) { 272 if (lint.isEnabled(LintCategory.DIVZERO)) 273 log.warning(LintCategory.DIVZERO, pos, "div.zero"); 274 } 275 276 /** 277 * Report any deferred diagnostics. 278 */ 279 public void reportDeferredDiagnostics() { 280 deprecationHandler.reportDeferredDiagnostic(); 281 uncheckedHandler.reportDeferredDiagnostic(); 282 sunApiHandler.reportDeferredDiagnostic(); 283 } 284 285 286 /** Report a failure to complete a class. 287 * @param pos Position to be used for error reporting. 288 * @param ex The failure to report. 289 */ 290 public Type completionError(DiagnosticPosition pos, CompletionFailure ex) { 291 log.error(JCDiagnostic.DiagnosticFlag.NON_DEFERRABLE, pos, "cant.access", ex.sym, ex.getDetailValue()); 292 if (ex instanceof ClassFinder.BadClassFile 293 && !suppressAbortOnBadClassFile) throw new Abort(); 294 else return syms.errType; 295 } 296 297 /** Report an error that wrong type tag was found. 298 * @param pos Position to be used for error reporting. 299 * @param required An internationalized string describing the type tag 300 * required. 301 * @param found The type that was found. 302 */ 303 Type typeTagError(DiagnosticPosition pos, Object required, Object found) { 304 // this error used to be raised by the parser, 305 // but has been delayed to this point: 306 if (found instanceof Type && ((Type)found).hasTag(VOID)) { 307 log.error(pos, "illegal.start.of.type"); 308 return syms.errType; 309 } 310 log.error(pos, "type.found.req", found, required); 311 return types.createErrorType(found instanceof Type ? (Type)found : syms.errType); 312 } 313 314 /** Report an error that symbol cannot be referenced before super 315 * has been called. 316 * @param pos Position to be used for error reporting. 317 * @param sym The referenced symbol. 318 */ 319 void earlyRefError(DiagnosticPosition pos, Symbol sym) { 320 log.error(pos, "cant.ref.before.ctor.called", sym); 321 } 322 323 /** Report duplicate declaration error. 324 */ 325 void duplicateError(DiagnosticPosition pos, Symbol sym) { 326 if (!sym.type.isErroneous()) { 327 Symbol location = sym.location(); 328 if (location.kind == MTH && 329 ((MethodSymbol)location).isStaticOrInstanceInit()) { 330 log.error(pos, "already.defined.in.clinit", kindName(sym), sym, 331 kindName(sym.location()), kindName(sym.location().enclClass()), 332 sym.location().enclClass()); 333 } else { 334 log.error(pos, "already.defined", kindName(sym), sym, 335 kindName(sym.location()), sym.location()); 336 } 337 } 338 } 339 340 /** Report array/varargs duplicate declaration 341 */ 342 void varargsDuplicateError(DiagnosticPosition pos, Symbol sym1, Symbol sym2) { 343 if (!sym1.type.isErroneous() && !sym2.type.isErroneous()) { 344 log.error(pos, "array.and.varargs", sym1, sym2, sym2.location()); 345 } 346 } 347 348/* ************************************************************************ 349 * duplicate declaration checking 350 *************************************************************************/ 351 352 /** Check that variable does not hide variable with same name in 353 * immediately enclosing local scope. 354 * @param pos Position for error reporting. 355 * @param v The symbol. 356 * @param s The scope. 357 */ 358 void checkTransparentVar(DiagnosticPosition pos, VarSymbol v, Scope s) { 359 for (Symbol sym : s.getSymbolsByName(v.name)) { 360 if (sym.owner != v.owner) break; 361 if (sym.kind == VAR && 362 sym.owner.kind.matches(KindSelector.VAL_MTH) && 363 v.name != names.error) { 364 duplicateError(pos, sym); 365 return; 366 } 367 } 368 } 369 370 /** Check that a class or interface does not hide a class or 371 * interface with same name in immediately enclosing local scope. 372 * @param pos Position for error reporting. 373 * @param c The symbol. 374 * @param s The scope. 375 */ 376 void checkTransparentClass(DiagnosticPosition pos, ClassSymbol c, Scope s) { 377 for (Symbol sym : s.getSymbolsByName(c.name)) { 378 if (sym.owner != c.owner) break; 379 if (sym.kind == TYP && !sym.type.hasTag(TYPEVAR) && 380 sym.owner.kind.matches(KindSelector.VAL_MTH) && 381 c.name != names.error) { 382 duplicateError(pos, sym); 383 return; 384 } 385 } 386 } 387 388 /** Check that class does not have the same name as one of 389 * its enclosing classes, or as a class defined in its enclosing scope. 390 * return true if class is unique in its enclosing scope. 391 * @param pos Position for error reporting. 392 * @param name The class name. 393 * @param s The enclosing scope. 394 */ 395 boolean checkUniqueClassName(DiagnosticPosition pos, Name name, Scope s) { 396 for (Symbol sym : s.getSymbolsByName(name, NON_RECURSIVE)) { 397 if (sym.kind == TYP && sym.name != names.error) { 398 duplicateError(pos, sym); 399 return false; 400 } 401 } 402 for (Symbol sym = s.owner; sym != null; sym = sym.owner) { 403 if (sym.kind == TYP && sym.name == name && sym.name != names.error) { 404 duplicateError(pos, sym); 405 return true; 406 } 407 } 408 return true; 409 } 410 411/* ************************************************************************* 412 * Class name generation 413 **************************************************************************/ 414 415 /** Return name of local class. 416 * This is of the form {@code <enclClass> $ n <classname> } 417 * where 418 * enclClass is the flat name of the enclosing class, 419 * classname is the simple name of the local class 420 */ 421 Name localClassName(ClassSymbol c) { 422 for (int i=1; ; i++) { 423 Name flatname = names. 424 fromString("" + c.owner.enclClass().flatname + 425 syntheticNameChar + i + 426 c.name); 427 if (compiled.get(flatname) == null) return flatname; 428 } 429 } 430 431 public void newRound() { 432 compiled.clear(); 433 } 434 435/* ************************************************************************* 436 * Type Checking 437 **************************************************************************/ 438 439 /** 440 * A check context is an object that can be used to perform compatibility 441 * checks - depending on the check context, meaning of 'compatibility' might 442 * vary significantly. 443 */ 444 public interface CheckContext { 445 /** 446 * Is type 'found' compatible with type 'req' in given context 447 */ 448 boolean compatible(Type found, Type req, Warner warn); 449 /** 450 * Report a check error 451 */ 452 void report(DiagnosticPosition pos, JCDiagnostic details); 453 /** 454 * Obtain a warner for this check context 455 */ 456 public Warner checkWarner(DiagnosticPosition pos, Type found, Type req); 457 458 public Infer.InferenceContext inferenceContext(); 459 460 public DeferredAttr.DeferredAttrContext deferredAttrContext(); 461 } 462 463 /** 464 * This class represent a check context that is nested within another check 465 * context - useful to check sub-expressions. The default behavior simply 466 * redirects all method calls to the enclosing check context leveraging 467 * the forwarding pattern. 468 */ 469 static class NestedCheckContext implements CheckContext { 470 CheckContext enclosingContext; 471 472 NestedCheckContext(CheckContext enclosingContext) { 473 this.enclosingContext = enclosingContext; 474 } 475 476 public boolean compatible(Type found, Type req, Warner warn) { 477 return enclosingContext.compatible(found, req, warn); 478 } 479 480 public void report(DiagnosticPosition pos, JCDiagnostic details) { 481 enclosingContext.report(pos, details); 482 } 483 484 public Warner checkWarner(DiagnosticPosition pos, Type found, Type req) { 485 return enclosingContext.checkWarner(pos, found, req); 486 } 487 488 public Infer.InferenceContext inferenceContext() { 489 return enclosingContext.inferenceContext(); 490 } 491 492 public DeferredAttrContext deferredAttrContext() { 493 return enclosingContext.deferredAttrContext(); 494 } 495 } 496 497 /** 498 * Check context to be used when evaluating assignment/return statements 499 */ 500 CheckContext basicHandler = new CheckContext() { 501 public void report(DiagnosticPosition pos, JCDiagnostic details) { 502 log.error(pos, "prob.found.req", details); 503 } 504 public boolean compatible(Type found, Type req, Warner warn) { 505 return types.isAssignable(found, req, warn); 506 } 507 508 public Warner checkWarner(DiagnosticPosition pos, Type found, Type req) { 509 return convertWarner(pos, found, req); 510 } 511 512 public InferenceContext inferenceContext() { 513 return infer.emptyContext; 514 } 515 516 public DeferredAttrContext deferredAttrContext() { 517 return deferredAttr.emptyDeferredAttrContext; 518 } 519 520 @Override 521 public String toString() { 522 return "CheckContext: basicHandler"; 523 } 524 }; 525 526 /** Check that a given type is assignable to a given proto-type. 527 * If it is, return the type, otherwise return errType. 528 * @param pos Position to be used for error reporting. 529 * @param found The type that was found. 530 * @param req The type that was required. 531 */ 532 public Type checkType(DiagnosticPosition pos, Type found, Type req) { 533 return checkType(pos, found, req, basicHandler); 534 } 535 536 Type checkType(final DiagnosticPosition pos, final Type found, final Type req, final CheckContext checkContext) { 537 final Infer.InferenceContext inferenceContext = checkContext.inferenceContext(); 538 if (inferenceContext.free(req) || inferenceContext.free(found)) { 539 inferenceContext.addFreeTypeListener(List.of(req, found), new FreeTypeListener() { 540 @Override 541 public void typesInferred(InferenceContext inferenceContext) { 542 checkType(pos, inferenceContext.asInstType(found), inferenceContext.asInstType(req), checkContext); 543 } 544 }); 545 } 546 if (req.hasTag(ERROR)) 547 return req; 548 if (req.hasTag(NONE)) 549 return found; 550 if (checkContext.compatible(found, req, checkContext.checkWarner(pos, found, req))) { 551 return found; 552 } else { 553 if (found.isNumeric() && req.isNumeric()) { 554 checkContext.report(pos, diags.fragment("possible.loss.of.precision", found, req)); 555 return types.createErrorType(found); 556 } 557 checkContext.report(pos, diags.fragment("inconvertible.types", found, req)); 558 return types.createErrorType(found); 559 } 560 } 561 562 /** Check that a given type can be cast to a given target type. 563 * Return the result of the cast. 564 * @param pos Position to be used for error reporting. 565 * @param found The type that is being cast. 566 * @param req The target type of the cast. 567 */ 568 Type checkCastable(DiagnosticPosition pos, Type found, Type req) { 569 return checkCastable(pos, found, req, basicHandler); 570 } 571 Type checkCastable(DiagnosticPosition pos, Type found, Type req, CheckContext checkContext) { 572 if (types.isCastable(found, req, castWarner(pos, found, req))) { 573 return req; 574 } else { 575 checkContext.report(pos, diags.fragment("inconvertible.types", found, req)); 576 return types.createErrorType(found); 577 } 578 } 579 580 /** Check for redundant casts (i.e. where source type is a subtype of target type) 581 * The problem should only be reported for non-292 cast 582 */ 583 public void checkRedundantCast(Env<AttrContext> env, final JCTypeCast tree) { 584 if (!tree.type.isErroneous() 585 && types.isSameType(tree.expr.type, tree.clazz.type) 586 && !(ignoreAnnotatedCasts && TreeInfo.containsTypeAnnotation(tree.clazz)) 587 && !is292targetTypeCast(tree)) { 588 deferredLintHandler.report(new DeferredLintHandler.LintLogger() { 589 @Override 590 public void report() { 591 if (lint.isEnabled(Lint.LintCategory.CAST)) 592 log.warning(Lint.LintCategory.CAST, 593 tree.pos(), "redundant.cast", tree.clazz.type); 594 } 595 }); 596 } 597 } 598 //where 599 private boolean is292targetTypeCast(JCTypeCast tree) { 600 boolean is292targetTypeCast = false; 601 JCExpression expr = TreeInfo.skipParens(tree.expr); 602 if (expr.hasTag(APPLY)) { 603 JCMethodInvocation apply = (JCMethodInvocation)expr; 604 Symbol sym = TreeInfo.symbol(apply.meth); 605 is292targetTypeCast = sym != null && 606 sym.kind == MTH && 607 (sym.flags() & HYPOTHETICAL) != 0; 608 } 609 return is292targetTypeCast; 610 } 611 612 private static final boolean ignoreAnnotatedCasts = true; 613 614 /** Check that a type is within some bounds. 615 * 616 * Used in TypeApply to verify that, e.g., X in {@code V<X>} is a valid 617 * type argument. 618 * @param a The type that should be bounded by bs. 619 * @param bound The bound. 620 */ 621 private boolean checkExtends(Type a, Type bound) { 622 if (a.isUnbound()) { 623 return true; 624 } else if (!a.hasTag(WILDCARD)) { 625 a = types.cvarUpperBound(a); 626 return types.isSubtype(a, bound); 627 } else if (a.isExtendsBound()) { 628 return types.isCastable(bound, types.wildUpperBound(a), types.noWarnings); 629 } else if (a.isSuperBound()) { 630 return !types.notSoftSubtype(types.wildLowerBound(a), bound); 631 } 632 return true; 633 } 634 635 /** Check that type is different from 'void'. 636 * @param pos Position to be used for error reporting. 637 * @param t The type to be checked. 638 */ 639 Type checkNonVoid(DiagnosticPosition pos, Type t) { 640 if (t.hasTag(VOID)) { 641 log.error(pos, "void.not.allowed.here"); 642 return types.createErrorType(t); 643 } else { 644 return t; 645 } 646 } 647 648 Type checkClassOrArrayType(DiagnosticPosition pos, Type t) { 649 if (!t.hasTag(CLASS) && !t.hasTag(ARRAY) && !t.hasTag(ERROR)) { 650 return typeTagError(pos, 651 diags.fragment("type.req.class.array"), 652 asTypeParam(t)); 653 } else { 654 return t; 655 } 656 } 657 658 /** Check that type is a class or interface type. 659 * @param pos Position to be used for error reporting. 660 * @param t The type to be checked. 661 */ 662 Type checkClassType(DiagnosticPosition pos, Type t) { 663 if (!t.hasTag(CLASS) && !t.hasTag(ERROR)) { 664 return typeTagError(pos, 665 diags.fragment("type.req.class"), 666 asTypeParam(t)); 667 } else { 668 return t; 669 } 670 } 671 //where 672 private Object asTypeParam(Type t) { 673 return (t.hasTag(TYPEVAR)) 674 ? diags.fragment("type.parameter", t) 675 : t; 676 } 677 678 /** Check that type is a valid qualifier for a constructor reference expression 679 */ 680 Type checkConstructorRefType(DiagnosticPosition pos, Type t) { 681 t = checkClassOrArrayType(pos, t); 682 if (t.hasTag(CLASS)) { 683 if ((t.tsym.flags() & (ABSTRACT | INTERFACE)) != 0) { 684 log.error(pos, "abstract.cant.be.instantiated", t.tsym); 685 t = types.createErrorType(t); 686 } else if ((t.tsym.flags() & ENUM) != 0) { 687 log.error(pos, "enum.cant.be.instantiated"); 688 t = types.createErrorType(t); 689 } else { 690 t = checkClassType(pos, t, true); 691 } 692 } else if (t.hasTag(ARRAY)) { 693 if (!types.isReifiable(((ArrayType)t).elemtype)) { 694 log.error(pos, "generic.array.creation"); 695 t = types.createErrorType(t); 696 } 697 } 698 return t; 699 } 700 701 /** Check that type is a class or interface type. 702 * @param pos Position to be used for error reporting. 703 * @param t The type to be checked. 704 * @param noBounds True if type bounds are illegal here. 705 */ 706 Type checkClassType(DiagnosticPosition pos, Type t, boolean noBounds) { 707 t = checkClassType(pos, t); 708 if (noBounds && t.isParameterized()) { 709 List<Type> args = t.getTypeArguments(); 710 while (args.nonEmpty()) { 711 if (args.head.hasTag(WILDCARD)) 712 return typeTagError(pos, 713 diags.fragment("type.req.exact"), 714 args.head); 715 args = args.tail; 716 } 717 } 718 return t; 719 } 720 721 /** Check that type is a reference type, i.e. a class, interface or array type 722 * or a type variable. 723 * @param pos Position to be used for error reporting. 724 * @param t The type to be checked. 725 */ 726 Type checkRefType(DiagnosticPosition pos, Type t) { 727 if (t.isReference()) 728 return t; 729 else 730 return typeTagError(pos, 731 diags.fragment("type.req.ref"), 732 t); 733 } 734 735 /** Check that each type is a reference type, i.e. a class, interface or array type 736 * or a type variable. 737 * @param trees Original trees, used for error reporting. 738 * @param types The types to be checked. 739 */ 740 List<Type> checkRefTypes(List<JCExpression> trees, List<Type> types) { 741 List<JCExpression> tl = trees; 742 for (List<Type> l = types; l.nonEmpty(); l = l.tail) { 743 l.head = checkRefType(tl.head.pos(), l.head); 744 tl = tl.tail; 745 } 746 return types; 747 } 748 749 /** Check that type is a null or reference type. 750 * @param pos Position to be used for error reporting. 751 * @param t The type to be checked. 752 */ 753 Type checkNullOrRefType(DiagnosticPosition pos, Type t) { 754 if (t.isReference() || t.hasTag(BOT)) 755 return t; 756 else 757 return typeTagError(pos, 758 diags.fragment("type.req.ref"), 759 t); 760 } 761 762 /** Check that flag set does not contain elements of two conflicting sets. s 763 * Return true if it doesn't. 764 * @param pos Position to be used for error reporting. 765 * @param flags The set of flags to be checked. 766 * @param set1 Conflicting flags set #1. 767 * @param set2 Conflicting flags set #2. 768 */ 769 boolean checkDisjoint(DiagnosticPosition pos, long flags, long set1, long set2) { 770 if ((flags & set1) != 0 && (flags & set2) != 0) { 771 log.error(pos, 772 "illegal.combination.of.modifiers", 773 asFlagSet(TreeInfo.firstFlag(flags & set1)), 774 asFlagSet(TreeInfo.firstFlag(flags & set2))); 775 return false; 776 } else 777 return true; 778 } 779 780 /** Check that usage of diamond operator is correct (i.e. diamond should not 781 * be used with non-generic classes or in anonymous class creation expressions) 782 */ 783 Type checkDiamond(JCNewClass tree, Type t) { 784 if (!TreeInfo.isDiamond(tree) || 785 t.isErroneous()) { 786 return checkClassType(tree.clazz.pos(), t, true); 787 } else if (tree.def != null && !allowDiamondWithAnonymousClassCreation) { 788 log.error(tree.clazz.pos(), 789 Errors.CantApplyDiamond1(t, Fragments.DiamondAndAnonClassNotSupportedInSource(source.name))); 790 return types.createErrorType(t); 791 } else if (t.tsym.type.getTypeArguments().isEmpty()) { 792 log.error(tree.clazz.pos(), 793 "cant.apply.diamond.1", 794 t, diags.fragment("diamond.non.generic", t)); 795 return types.createErrorType(t); 796 } else if (tree.typeargs != null && 797 tree.typeargs.nonEmpty()) { 798 log.error(tree.clazz.pos(), 799 "cant.apply.diamond.1", 800 t, diags.fragment("diamond.and.explicit.params", t)); 801 return types.createErrorType(t); 802 } else { 803 return t; 804 } 805 } 806 807 /** Check that the type inferred using the diamond operator does not contain 808 * non-denotable types such as captured types or intersection types. 809 * @param t the type inferred using the diamond operator 810 * @return the (possibly empty) list of non-denotable types. 811 */ 812 List<Type> checkDiamondDenotable(ClassType t) { 813 ListBuffer<Type> buf = new ListBuffer<>(); 814 for (Type arg : t.getTypeArguments()) { 815 if (!diamondTypeChecker.visit(arg, null)) { 816 buf.append(arg); 817 } 818 } 819 return buf.toList(); 820 } 821 // where 822 823 /** diamondTypeChecker: A type visitor that descends down the given type looking for non-denotable 824 * types. The visit methods return false as soon as a non-denotable type is encountered and true 825 * otherwise. 826 */ 827 private static final Types.SimpleVisitor<Boolean, Void> diamondTypeChecker = new Types.SimpleVisitor<Boolean, Void>() { 828 @Override 829 public Boolean visitType(Type t, Void s) { 830 return true; 831 } 832 @Override 833 public Boolean visitClassType(ClassType t, Void s) { 834 if (t.isCompound()) { 835 return false; 836 } 837 for (Type targ : t.getTypeArguments()) { 838 if (!visit(targ, s)) { 839 return false; 840 } 841 } 842 return true; 843 } 844 @Override 845 public Boolean visitCapturedType(CapturedType t, Void s) { 846 return false; 847 } 848 849 @Override 850 public Boolean visitArrayType(ArrayType t, Void s) { 851 return visit(t.elemtype, s); 852 } 853 854 @Override 855 public Boolean visitWildcardType(WildcardType t, Void s) { 856 return visit(t.type, s); 857 } 858 }; 859 860 void checkVarargsMethodDecl(Env<AttrContext> env, JCMethodDecl tree) { 861 MethodSymbol m = tree.sym; 862 if (!allowSimplifiedVarargs) return; 863 boolean hasTrustMeAnno = m.attribute(syms.trustMeType.tsym) != null; 864 Type varargElemType = null; 865 if (m.isVarArgs()) { 866 varargElemType = types.elemtype(tree.params.last().type); 867 } 868 if (hasTrustMeAnno && !isTrustMeAllowedOnMethod(m)) { 869 if (varargElemType != null) { 870 log.error(tree, 871 "varargs.invalid.trustme.anno", 872 syms.trustMeType.tsym, 873 allowPrivateSafeVarargs ? 874 diags.fragment("varargs.trustme.on.virtual.varargs", m) : 875 diags.fragment("varargs.trustme.on.virtual.varargs.final.only", m)); 876 } else { 877 log.error(tree, 878 "varargs.invalid.trustme.anno", 879 syms.trustMeType.tsym, 880 diags.fragment("varargs.trustme.on.non.varargs.meth", m)); 881 } 882 } else if (hasTrustMeAnno && varargElemType != null && 883 types.isReifiable(varargElemType)) { 884 warnUnsafeVararg(tree, 885 "varargs.redundant.trustme.anno", 886 syms.trustMeType.tsym, 887 diags.fragment("varargs.trustme.on.reifiable.varargs", varargElemType)); 888 } 889 else if (!hasTrustMeAnno && varargElemType != null && 890 !types.isReifiable(varargElemType)) { 891 warnUnchecked(tree.params.head.pos(), "unchecked.varargs.non.reifiable.type", varargElemType); 892 } 893 } 894 //where 895 private boolean isTrustMeAllowedOnMethod(Symbol s) { 896 return (s.flags() & VARARGS) != 0 && 897 (s.isConstructor() || 898 (s.flags() & (STATIC | FINAL | 899 (allowPrivateSafeVarargs ? PRIVATE : 0) )) != 0); 900 } 901 902 Type checkMethod(final Type mtype, 903 final Symbol sym, 904 final Env<AttrContext> env, 905 final List<JCExpression> argtrees, 906 final List<Type> argtypes, 907 final boolean useVarargs, 908 InferenceContext inferenceContext) { 909 // System.out.println("call : " + env.tree); 910 // System.out.println("method : " + owntype); 911 // System.out.println("actuals: " + argtypes); 912 if (inferenceContext.free(mtype)) { 913 inferenceContext.addFreeTypeListener(List.of(mtype), new FreeTypeListener() { 914 public void typesInferred(InferenceContext inferenceContext) { 915 checkMethod(inferenceContext.asInstType(mtype), sym, env, argtrees, argtypes, useVarargs, inferenceContext); 916 } 917 }); 918 return mtype; 919 } 920 Type owntype = mtype; 921 List<Type> formals = owntype.getParameterTypes(); 922 List<Type> nonInferred = sym.type.getParameterTypes(); 923 if (nonInferred.length() != formals.length()) nonInferred = formals; 924 Type last = useVarargs ? formals.last() : null; 925 if (sym.name == names.init && sym.owner == syms.enumSym) { 926 formals = formals.tail.tail; 927 nonInferred = nonInferred.tail.tail; 928 } 929 List<JCExpression> args = argtrees; 930 if (args != null) { 931 //this is null when type-checking a method reference 932 while (formals.head != last) { 933 JCTree arg = args.head; 934 Warner warn = convertWarner(arg.pos(), arg.type, nonInferred.head); 935 assertConvertible(arg, arg.type, formals.head, warn); 936 args = args.tail; 937 formals = formals.tail; 938 nonInferred = nonInferred.tail; 939 } 940 if (useVarargs) { 941 Type varArg = types.elemtype(last); 942 while (args.tail != null) { 943 JCTree arg = args.head; 944 Warner warn = convertWarner(arg.pos(), arg.type, varArg); 945 assertConvertible(arg, arg.type, varArg, warn); 946 args = args.tail; 947 } 948 } else if ((sym.flags() & (VARARGS | SIGNATURE_POLYMORPHIC)) == VARARGS) { 949 // non-varargs call to varargs method 950 Type varParam = owntype.getParameterTypes().last(); 951 Type lastArg = argtypes.last(); 952 if (types.isSubtypeUnchecked(lastArg, types.elemtype(varParam)) && 953 !types.isSameType(types.erasure(varParam), types.erasure(lastArg))) 954 log.warning(argtrees.last().pos(), "inexact.non-varargs.call", 955 types.elemtype(varParam), varParam); 956 } 957 } 958 if (useVarargs) { 959 Type argtype = owntype.getParameterTypes().last(); 960 if (!types.isReifiable(argtype) && 961 (!allowSimplifiedVarargs || 962 sym.baseSymbol().attribute(syms.trustMeType.tsym) == null || 963 !isTrustMeAllowedOnMethod(sym))) { 964 warnUnchecked(env.tree.pos(), 965 "unchecked.generic.array.creation", 966 argtype); 967 } 968 if ((sym.baseSymbol().flags() & SIGNATURE_POLYMORPHIC) == 0) { 969 TreeInfo.setVarargsElement(env.tree, types.elemtype(argtype)); 970 } 971 } 972 PolyKind pkind = (sym.type.hasTag(FORALL) && 973 sym.type.getReturnType().containsAny(((ForAll)sym.type).tvars)) ? 974 PolyKind.POLY : PolyKind.STANDALONE; 975 TreeInfo.setPolyKind(env.tree, pkind); 976 return owntype; 977 } 978 //where 979 private void assertConvertible(JCTree tree, Type actual, Type formal, Warner warn) { 980 if (types.isConvertible(actual, formal, warn)) 981 return; 982 983 if (formal.isCompound() 984 && types.isSubtype(actual, types.supertype(formal)) 985 && types.isSubtypeUnchecked(actual, types.interfaces(formal), warn)) 986 return; 987 } 988 989 /** 990 * Check that type 't' is a valid instantiation of a generic class 991 * (see JLS 4.5) 992 * 993 * @param t class type to be checked 994 * @return true if 't' is well-formed 995 */ 996 public boolean checkValidGenericType(Type t) { 997 return firstIncompatibleTypeArg(t) == null; 998 } 999 //WHERE 1000 private Type firstIncompatibleTypeArg(Type type) { 1001 List<Type> formals = type.tsym.type.allparams(); 1002 List<Type> actuals = type.allparams(); 1003 List<Type> args = type.getTypeArguments(); 1004 List<Type> forms = type.tsym.type.getTypeArguments(); 1005 ListBuffer<Type> bounds_buf = new ListBuffer<>(); 1006 1007 // For matching pairs of actual argument types `a' and 1008 // formal type parameters with declared bound `b' ... 1009 while (args.nonEmpty() && forms.nonEmpty()) { 1010 // exact type arguments needs to know their 1011 // bounds (for upper and lower bound 1012 // calculations). So we create new bounds where 1013 // type-parameters are replaced with actuals argument types. 1014 bounds_buf.append(types.subst(forms.head.getUpperBound(), formals, actuals)); 1015 args = args.tail; 1016 forms = forms.tail; 1017 } 1018 1019 args = type.getTypeArguments(); 1020 List<Type> tvars_cap = types.substBounds(formals, 1021 formals, 1022 types.capture(type).allparams()); 1023 while (args.nonEmpty() && tvars_cap.nonEmpty()) { 1024 // Let the actual arguments know their bound 1025 args.head.withTypeVar((TypeVar)tvars_cap.head); 1026 args = args.tail; 1027 tvars_cap = tvars_cap.tail; 1028 } 1029 1030 args = type.getTypeArguments(); 1031 List<Type> bounds = bounds_buf.toList(); 1032 1033 while (args.nonEmpty() && bounds.nonEmpty()) { 1034 Type actual = args.head; 1035 if (!isTypeArgErroneous(actual) && 1036 !bounds.head.isErroneous() && 1037 !checkExtends(actual, bounds.head)) { 1038 return args.head; 1039 } 1040 args = args.tail; 1041 bounds = bounds.tail; 1042 } 1043 1044 args = type.getTypeArguments(); 1045 bounds = bounds_buf.toList(); 1046 1047 for (Type arg : types.capture(type).getTypeArguments()) { 1048 if (arg.hasTag(TYPEVAR) && 1049 arg.getUpperBound().isErroneous() && 1050 !bounds.head.isErroneous() && 1051 !isTypeArgErroneous(args.head)) { 1052 return args.head; 1053 } 1054 bounds = bounds.tail; 1055 args = args.tail; 1056 } 1057 1058 return null; 1059 } 1060 //where 1061 boolean isTypeArgErroneous(Type t) { 1062 return isTypeArgErroneous.visit(t); 1063 } 1064 1065 Types.UnaryVisitor<Boolean> isTypeArgErroneous = new Types.UnaryVisitor<Boolean>() { 1066 public Boolean visitType(Type t, Void s) { 1067 return t.isErroneous(); 1068 } 1069 @Override 1070 public Boolean visitTypeVar(TypeVar t, Void s) { 1071 return visit(t.getUpperBound()); 1072 } 1073 @Override 1074 public Boolean visitCapturedType(CapturedType t, Void s) { 1075 return visit(t.getUpperBound()) || 1076 visit(t.getLowerBound()); 1077 } 1078 @Override 1079 public Boolean visitWildcardType(WildcardType t, Void s) { 1080 return visit(t.type); 1081 } 1082 }; 1083 1084 /** Check that given modifiers are legal for given symbol and 1085 * return modifiers together with any implicit modifiers for that symbol. 1086 * Warning: we can't use flags() here since this method 1087 * is called during class enter, when flags() would cause a premature 1088 * completion. 1089 * @param pos Position to be used for error reporting. 1090 * @param flags The set of modifiers given in a definition. 1091 * @param sym The defined symbol. 1092 */ 1093 long checkFlags(DiagnosticPosition pos, long flags, Symbol sym, JCTree tree) { 1094 long mask; 1095 long implicit = 0; 1096 1097 switch (sym.kind) { 1098 case VAR: 1099 if (TreeInfo.isReceiverParam(tree)) 1100 mask = ReceiverParamFlags; 1101 else if (sym.owner.kind != TYP) 1102 mask = LocalVarFlags; 1103 else if ((sym.owner.flags_field & INTERFACE) != 0) 1104 mask = implicit = InterfaceVarFlags; 1105 else 1106 mask = VarFlags; 1107 break; 1108 case MTH: 1109 if (sym.name == names.init) { 1110 if ((sym.owner.flags_field & ENUM) != 0) { 1111 // enum constructors cannot be declared public or 1112 // protected and must be implicitly or explicitly 1113 // private 1114 implicit = PRIVATE; 1115 mask = PRIVATE; 1116 } else 1117 mask = ConstructorFlags; 1118 } else if ((sym.owner.flags_field & INTERFACE) != 0) { 1119 if ((sym.owner.flags_field & ANNOTATION) != 0) { 1120 mask = AnnotationTypeElementMask; 1121 implicit = PUBLIC | ABSTRACT; 1122 } else if ((flags & (DEFAULT | STATIC | PRIVATE)) != 0) { 1123 mask = InterfaceMethodMask; 1124 implicit = (flags & PRIVATE) != 0 ? 0 : PUBLIC; 1125 if ((flags & DEFAULT) != 0) { 1126 implicit |= ABSTRACT; 1127 } 1128 } else { 1129 mask = implicit = InterfaceMethodFlags; 1130 } 1131 } else { 1132 mask = MethodFlags; 1133 } 1134 // Imply STRICTFP if owner has STRICTFP set. 1135 if (((flags|implicit) & Flags.ABSTRACT) == 0 || 1136 ((flags) & Flags.DEFAULT) != 0) 1137 implicit |= sym.owner.flags_field & STRICTFP; 1138 break; 1139 case TYP: 1140 if (sym.isLocal()) { 1141 mask = LocalClassFlags; 1142 if (sym.name.isEmpty()) { // Anonymous class 1143 // JLS: Anonymous classes are final. 1144 implicit |= FINAL; 1145 } 1146 if ((sym.owner.flags_field & STATIC) == 0 && 1147 (flags & ENUM) != 0) 1148 log.error(pos, "enums.must.be.static"); 1149 } else if (sym.owner.kind == TYP) { 1150 mask = MemberClassFlags; 1151 if (sym.owner.owner.kind == PCK || 1152 (sym.owner.flags_field & STATIC) != 0) 1153 mask |= STATIC; 1154 else if ((flags & ENUM) != 0) 1155 log.error(pos, "enums.must.be.static"); 1156 // Nested interfaces and enums are always STATIC (Spec ???) 1157 if ((flags & (INTERFACE | ENUM)) != 0 ) implicit = STATIC; 1158 } else { 1159 mask = ClassFlags; 1160 } 1161 // Interfaces are always ABSTRACT 1162 if ((flags & INTERFACE) != 0) implicit |= ABSTRACT; 1163 1164 if ((flags & ENUM) != 0) { 1165 // enums can't be declared abstract or final 1166 mask &= ~(ABSTRACT | FINAL); 1167 implicit |= implicitEnumFinalFlag(tree); 1168 } 1169 // Imply STRICTFP if owner has STRICTFP set. 1170 implicit |= sym.owner.flags_field & STRICTFP; 1171 break; 1172 default: 1173 throw new AssertionError(); 1174 } 1175 long illegal = flags & ExtendedStandardFlags & ~mask; 1176 if (illegal != 0) { 1177 if ((illegal & INTERFACE) != 0) { 1178 log.error(pos, "intf.not.allowed.here"); 1179 mask |= INTERFACE; 1180 } 1181 else { 1182 log.error(pos, 1183 "mod.not.allowed.here", asFlagSet(illegal)); 1184 } 1185 } 1186 else if ((sym.kind == TYP || 1187 // ISSUE: Disallowing abstract&private is no longer appropriate 1188 // in the presence of inner classes. Should it be deleted here? 1189 checkDisjoint(pos, flags, 1190 ABSTRACT, 1191 PRIVATE | STATIC | DEFAULT)) 1192 && 1193 checkDisjoint(pos, flags, 1194 STATIC | PRIVATE, 1195 DEFAULT) 1196 && 1197 checkDisjoint(pos, flags, 1198 ABSTRACT | INTERFACE, 1199 FINAL | NATIVE | SYNCHRONIZED) 1200 && 1201 checkDisjoint(pos, flags, 1202 PUBLIC, 1203 PRIVATE | PROTECTED) 1204 && 1205 checkDisjoint(pos, flags, 1206 PRIVATE, 1207 PUBLIC | PROTECTED) 1208 && 1209 checkDisjoint(pos, flags, 1210 FINAL, 1211 VOLATILE) 1212 && 1213 (sym.kind == TYP || 1214 checkDisjoint(pos, flags, 1215 ABSTRACT | NATIVE, 1216 STRICTFP))) { 1217 // skip 1218 } 1219 return flags & (mask | ~ExtendedStandardFlags) | implicit; 1220 } 1221 1222 1223 /** Determine if this enum should be implicitly final. 1224 * 1225 * If the enum has no specialized enum contants, it is final. 1226 * 1227 * If the enum does have specialized enum contants, it is 1228 * <i>not</i> final. 1229 */ 1230 private long implicitEnumFinalFlag(JCTree tree) { 1231 if (!tree.hasTag(CLASSDEF)) return 0; 1232 class SpecialTreeVisitor extends JCTree.Visitor { 1233 boolean specialized; 1234 SpecialTreeVisitor() { 1235 this.specialized = false; 1236 } 1237 1238 @Override 1239 public void visitTree(JCTree tree) { /* no-op */ } 1240 1241 @Override 1242 public void visitVarDef(JCVariableDecl tree) { 1243 if ((tree.mods.flags & ENUM) != 0) { 1244 if (tree.init instanceof JCNewClass && 1245 ((JCNewClass) tree.init).def != null) { 1246 specialized = true; 1247 } 1248 } 1249 } 1250 } 1251 1252 SpecialTreeVisitor sts = new SpecialTreeVisitor(); 1253 JCClassDecl cdef = (JCClassDecl) tree; 1254 for (JCTree defs: cdef.defs) { 1255 defs.accept(sts); 1256 if (sts.specialized) return 0; 1257 } 1258 return FINAL; 1259 } 1260 1261/* ************************************************************************* 1262 * Type Validation 1263 **************************************************************************/ 1264 1265 /** Validate a type expression. That is, 1266 * check that all type arguments of a parametric type are within 1267 * their bounds. This must be done in a second phase after type attribution 1268 * since a class might have a subclass as type parameter bound. E.g: 1269 * 1270 * <pre>{@code 1271 * class B<A extends C> { ... } 1272 * class C extends B<C> { ... } 1273 * }</pre> 1274 * 1275 * and we can't make sure that the bound is already attributed because 1276 * of possible cycles. 1277 * 1278 * Visitor method: Validate a type expression, if it is not null, catching 1279 * and reporting any completion failures. 1280 */ 1281 void validate(JCTree tree, Env<AttrContext> env) { 1282 validate(tree, env, true); 1283 } 1284 void validate(JCTree tree, Env<AttrContext> env, boolean checkRaw) { 1285 new Validator(env).validateTree(tree, checkRaw, true); 1286 } 1287 1288 /** Visitor method: Validate a list of type expressions. 1289 */ 1290 void validate(List<? extends JCTree> trees, Env<AttrContext> env) { 1291 for (List<? extends JCTree> l = trees; l.nonEmpty(); l = l.tail) 1292 validate(l.head, env); 1293 } 1294 1295 /** A visitor class for type validation. 1296 */ 1297 class Validator extends JCTree.Visitor { 1298 1299 boolean checkRaw; 1300 boolean isOuter; 1301 Env<AttrContext> env; 1302 1303 Validator(Env<AttrContext> env) { 1304 this.env = env; 1305 } 1306 1307 @Override 1308 public void visitTypeArray(JCArrayTypeTree tree) { 1309 validateTree(tree.elemtype, checkRaw, isOuter); 1310 } 1311 1312 @Override 1313 public void visitTypeApply(JCTypeApply tree) { 1314 if (tree.type.hasTag(CLASS)) { 1315 List<JCExpression> args = tree.arguments; 1316 List<Type> forms = tree.type.tsym.type.getTypeArguments(); 1317 1318 Type incompatibleArg = firstIncompatibleTypeArg(tree.type); 1319 if (incompatibleArg != null) { 1320 for (JCTree arg : tree.arguments) { 1321 if (arg.type == incompatibleArg) { 1322 log.error(arg, "not.within.bounds", incompatibleArg, forms.head); 1323 } 1324 forms = forms.tail; 1325 } 1326 } 1327 1328 forms = tree.type.tsym.type.getTypeArguments(); 1329 1330 boolean is_java_lang_Class = tree.type.tsym.flatName() == names.java_lang_Class; 1331 1332 // For matching pairs of actual argument types `a' and 1333 // formal type parameters with declared bound `b' ... 1334 while (args.nonEmpty() && forms.nonEmpty()) { 1335 validateTree(args.head, 1336 !(isOuter && is_java_lang_Class), 1337 false); 1338 args = args.tail; 1339 forms = forms.tail; 1340 } 1341 1342 // Check that this type is either fully parameterized, or 1343 // not parameterized at all. 1344 if (tree.type.getEnclosingType().isRaw()) 1345 log.error(tree.pos(), "improperly.formed.type.inner.raw.param"); 1346 if (tree.clazz.hasTag(SELECT)) 1347 visitSelectInternal((JCFieldAccess)tree.clazz); 1348 } 1349 } 1350 1351 @Override 1352 public void visitTypeParameter(JCTypeParameter tree) { 1353 validateTrees(tree.bounds, true, isOuter); 1354 checkClassBounds(tree.pos(), tree.type); 1355 } 1356 1357 @Override 1358 public void visitWildcard(JCWildcard tree) { 1359 if (tree.inner != null) 1360 validateTree(tree.inner, true, isOuter); 1361 } 1362 1363 @Override 1364 public void visitSelect(JCFieldAccess tree) { 1365 if (tree.type.hasTag(CLASS)) { 1366 visitSelectInternal(tree); 1367 1368 // Check that this type is either fully parameterized, or 1369 // not parameterized at all. 1370 if (tree.selected.type.isParameterized() && tree.type.tsym.type.getTypeArguments().nonEmpty()) 1371 log.error(tree.pos(), "improperly.formed.type.param.missing"); 1372 } 1373 } 1374 1375 public void visitSelectInternal(JCFieldAccess tree) { 1376 if (tree.type.tsym.isStatic() && 1377 tree.selected.type.isParameterized()) { 1378 // The enclosing type is not a class, so we are 1379 // looking at a static member type. However, the 1380 // qualifying expression is parameterized. 1381 log.error(tree.pos(), "cant.select.static.class.from.param.type"); 1382 } else { 1383 // otherwise validate the rest of the expression 1384 tree.selected.accept(this); 1385 } 1386 } 1387 1388 @Override 1389 public void visitAnnotatedType(JCAnnotatedType tree) { 1390 tree.underlyingType.accept(this); 1391 } 1392 1393 @Override 1394 public void visitTypeIdent(JCPrimitiveTypeTree that) { 1395 if (that.type.hasTag(TypeTag.VOID)) { 1396 log.error(that.pos(), "void.not.allowed.here"); 1397 } 1398 super.visitTypeIdent(that); 1399 } 1400 1401 /** Default visitor method: do nothing. 1402 */ 1403 @Override 1404 public void visitTree(JCTree tree) { 1405 } 1406 1407 public void validateTree(JCTree tree, boolean checkRaw, boolean isOuter) { 1408 if (tree != null) { 1409 boolean prevCheckRaw = this.checkRaw; 1410 this.checkRaw = checkRaw; 1411 this.isOuter = isOuter; 1412 1413 try { 1414 tree.accept(this); 1415 if (checkRaw) 1416 checkRaw(tree, env); 1417 } catch (CompletionFailure ex) { 1418 completionError(tree.pos(), ex); 1419 } finally { 1420 this.checkRaw = prevCheckRaw; 1421 } 1422 } 1423 } 1424 1425 public void validateTrees(List<? extends JCTree> trees, boolean checkRaw, boolean isOuter) { 1426 for (List<? extends JCTree> l = trees; l.nonEmpty(); l = l.tail) 1427 validateTree(l.head, checkRaw, isOuter); 1428 } 1429 } 1430 1431 void checkRaw(JCTree tree, Env<AttrContext> env) { 1432 if (lint.isEnabled(LintCategory.RAW) && 1433 tree.type.hasTag(CLASS) && 1434 !TreeInfo.isDiamond(tree) && 1435 !withinAnonConstr(env) && 1436 tree.type.isRaw()) { 1437 log.warning(LintCategory.RAW, 1438 tree.pos(), "raw.class.use", tree.type, tree.type.tsym.type); 1439 } 1440 } 1441 //where 1442 private boolean withinAnonConstr(Env<AttrContext> env) { 1443 return env.enclClass.name.isEmpty() && 1444 env.enclMethod != null && env.enclMethod.name == names.init; 1445 } 1446 1447/* ************************************************************************* 1448 * Exception checking 1449 **************************************************************************/ 1450 1451 /* The following methods treat classes as sets that contain 1452 * the class itself and all their subclasses 1453 */ 1454 1455 /** Is given type a subtype of some of the types in given list? 1456 */ 1457 boolean subset(Type t, List<Type> ts) { 1458 for (List<Type> l = ts; l.nonEmpty(); l = l.tail) 1459 if (types.isSubtype(t, l.head)) return true; 1460 return false; 1461 } 1462 1463 /** Is given type a subtype or supertype of 1464 * some of the types in given list? 1465 */ 1466 boolean intersects(Type t, List<Type> ts) { 1467 for (List<Type> l = ts; l.nonEmpty(); l = l.tail) 1468 if (types.isSubtype(t, l.head) || types.isSubtype(l.head, t)) return true; 1469 return false; 1470 } 1471 1472 /** Add type set to given type list, unless it is a subclass of some class 1473 * in the list. 1474 */ 1475 List<Type> incl(Type t, List<Type> ts) { 1476 return subset(t, ts) ? ts : excl(t, ts).prepend(t); 1477 } 1478 1479 /** Remove type set from type set list. 1480 */ 1481 List<Type> excl(Type t, List<Type> ts) { 1482 if (ts.isEmpty()) { 1483 return ts; 1484 } else { 1485 List<Type> ts1 = excl(t, ts.tail); 1486 if (types.isSubtype(ts.head, t)) return ts1; 1487 else if (ts1 == ts.tail) return ts; 1488 else return ts1.prepend(ts.head); 1489 } 1490 } 1491 1492 /** Form the union of two type set lists. 1493 */ 1494 List<Type> union(List<Type> ts1, List<Type> ts2) { 1495 List<Type> ts = ts1; 1496 for (List<Type> l = ts2; l.nonEmpty(); l = l.tail) 1497 ts = incl(l.head, ts); 1498 return ts; 1499 } 1500 1501 /** Form the difference of two type lists. 1502 */ 1503 List<Type> diff(List<Type> ts1, List<Type> ts2) { 1504 List<Type> ts = ts1; 1505 for (List<Type> l = ts2; l.nonEmpty(); l = l.tail) 1506 ts = excl(l.head, ts); 1507 return ts; 1508 } 1509 1510 /** Form the intersection of two type lists. 1511 */ 1512 public List<Type> intersect(List<Type> ts1, List<Type> ts2) { 1513 List<Type> ts = List.nil(); 1514 for (List<Type> l = ts1; l.nonEmpty(); l = l.tail) 1515 if (subset(l.head, ts2)) ts = incl(l.head, ts); 1516 for (List<Type> l = ts2; l.nonEmpty(); l = l.tail) 1517 if (subset(l.head, ts1)) ts = incl(l.head, ts); 1518 return ts; 1519 } 1520 1521 /** Is exc an exception symbol that need not be declared? 1522 */ 1523 boolean isUnchecked(ClassSymbol exc) { 1524 return 1525 exc.kind == ERR || 1526 exc.isSubClass(syms.errorType.tsym, types) || 1527 exc.isSubClass(syms.runtimeExceptionType.tsym, types); 1528 } 1529 1530 /** Is exc an exception type that need not be declared? 1531 */ 1532 boolean isUnchecked(Type exc) { 1533 return 1534 (exc.hasTag(TYPEVAR)) ? isUnchecked(types.supertype(exc)) : 1535 (exc.hasTag(CLASS)) ? isUnchecked((ClassSymbol)exc.tsym) : 1536 exc.hasTag(BOT); 1537 } 1538 1539 /** Same, but handling completion failures. 1540 */ 1541 boolean isUnchecked(DiagnosticPosition pos, Type exc) { 1542 try { 1543 return isUnchecked(exc); 1544 } catch (CompletionFailure ex) { 1545 completionError(pos, ex); 1546 return true; 1547 } 1548 } 1549 1550 /** Is exc handled by given exception list? 1551 */ 1552 boolean isHandled(Type exc, List<Type> handled) { 1553 return isUnchecked(exc) || subset(exc, handled); 1554 } 1555 1556 /** Return all exceptions in thrown list that are not in handled list. 1557 * @param thrown The list of thrown exceptions. 1558 * @param handled The list of handled exceptions. 1559 */ 1560 List<Type> unhandled(List<Type> thrown, List<Type> handled) { 1561 List<Type> unhandled = List.nil(); 1562 for (List<Type> l = thrown; l.nonEmpty(); l = l.tail) 1563 if (!isHandled(l.head, handled)) unhandled = unhandled.prepend(l.head); 1564 return unhandled; 1565 } 1566 1567/* ************************************************************************* 1568 * Overriding/Implementation checking 1569 **************************************************************************/ 1570 1571 /** The level of access protection given by a flag set, 1572 * where PRIVATE is highest and PUBLIC is lowest. 1573 */ 1574 static int protection(long flags) { 1575 switch ((short)(flags & AccessFlags)) { 1576 case PRIVATE: return 3; 1577 case PROTECTED: return 1; 1578 default: 1579 case PUBLIC: return 0; 1580 case 0: return 2; 1581 } 1582 } 1583 1584 /** A customized "cannot override" error message. 1585 * @param m The overriding method. 1586 * @param other The overridden method. 1587 * @return An internationalized string. 1588 */ 1589 Object cannotOverride(MethodSymbol m, MethodSymbol other) { 1590 String key; 1591 if ((other.owner.flags() & INTERFACE) == 0) 1592 key = "cant.override"; 1593 else if ((m.owner.flags() & INTERFACE) == 0) 1594 key = "cant.implement"; 1595 else 1596 key = "clashes.with"; 1597 return diags.fragment(key, m, m.location(), other, other.location()); 1598 } 1599 1600 /** A customized "override" warning message. 1601 * @param m The overriding method. 1602 * @param other The overridden method. 1603 * @return An internationalized string. 1604 */ 1605 Object uncheckedOverrides(MethodSymbol m, MethodSymbol other) { 1606 String key; 1607 if ((other.owner.flags() & INTERFACE) == 0) 1608 key = "unchecked.override"; 1609 else if ((m.owner.flags() & INTERFACE) == 0) 1610 key = "unchecked.implement"; 1611 else 1612 key = "unchecked.clash.with"; 1613 return diags.fragment(key, m, m.location(), other, other.location()); 1614 } 1615 1616 /** A customized "override" warning message. 1617 * @param m The overriding method. 1618 * @param other The overridden method. 1619 * @return An internationalized string. 1620 */ 1621 Object varargsOverrides(MethodSymbol m, MethodSymbol other) { 1622 String key; 1623 if ((other.owner.flags() & INTERFACE) == 0) 1624 key = "varargs.override"; 1625 else if ((m.owner.flags() & INTERFACE) == 0) 1626 key = "varargs.implement"; 1627 else 1628 key = "varargs.clash.with"; 1629 return diags.fragment(key, m, m.location(), other, other.location()); 1630 } 1631 1632 /** Check that this method conforms with overridden method 'other'. 1633 * where `origin' is the class where checking started. 1634 * Complications: 1635 * (1) Do not check overriding of synthetic methods 1636 * (reason: they might be final). 1637 * todo: check whether this is still necessary. 1638 * (2) Admit the case where an interface proxy throws fewer exceptions 1639 * than the method it implements. Augment the proxy methods with the 1640 * undeclared exceptions in this case. 1641 * (3) When generics are enabled, admit the case where an interface proxy 1642 * has a result type 1643 * extended by the result type of the method it implements. 1644 * Change the proxies result type to the smaller type in this case. 1645 * 1646 * @param tree The tree from which positions 1647 * are extracted for errors. 1648 * @param m The overriding method. 1649 * @param other The overridden method. 1650 * @param origin The class of which the overriding method 1651 * is a member. 1652 */ 1653 void checkOverride(JCTree tree, 1654 MethodSymbol m, 1655 MethodSymbol other, 1656 ClassSymbol origin) { 1657 // Don't check overriding of synthetic methods or by bridge methods. 1658 if ((m.flags() & (SYNTHETIC|BRIDGE)) != 0 || (other.flags() & SYNTHETIC) != 0) { 1659 return; 1660 } 1661 1662 // Error if static method overrides instance method (JLS 8.4.6.2). 1663 if ((m.flags() & STATIC) != 0 && 1664 (other.flags() & STATIC) == 0) { 1665 log.error(TreeInfo.diagnosticPositionFor(m, tree), "override.static", 1666 cannotOverride(m, other)); 1667 m.flags_field |= BAD_OVERRIDE; 1668 return; 1669 } 1670 1671 // Error if instance method overrides static or final 1672 // method (JLS 8.4.6.1). 1673 if ((other.flags() & FINAL) != 0 || 1674 (m.flags() & STATIC) == 0 && 1675 (other.flags() & STATIC) != 0) { 1676 log.error(TreeInfo.diagnosticPositionFor(m, tree), "override.meth", 1677 cannotOverride(m, other), 1678 asFlagSet(other.flags() & (FINAL | STATIC))); 1679 m.flags_field |= BAD_OVERRIDE; 1680 return; 1681 } 1682 1683 if ((m.owner.flags() & ANNOTATION) != 0) { 1684 // handled in validateAnnotationMethod 1685 return; 1686 } 1687 1688 // Error if overriding method has weaker access (JLS 8.4.6.3). 1689 if (protection(m.flags()) > protection(other.flags())) { 1690 log.error(TreeInfo.diagnosticPositionFor(m, tree), "override.weaker.access", 1691 cannotOverride(m, other), 1692 (other.flags() & AccessFlags) == 0 ? 1693 "package" : 1694 asFlagSet(other.flags() & AccessFlags)); 1695 m.flags_field |= BAD_OVERRIDE; 1696 return; 1697 } 1698 1699 Type mt = types.memberType(origin.type, m); 1700 Type ot = types.memberType(origin.type, other); 1701 // Error if overriding result type is different 1702 // (or, in the case of generics mode, not a subtype) of 1703 // overridden result type. We have to rename any type parameters 1704 // before comparing types. 1705 List<Type> mtvars = mt.getTypeArguments(); 1706 List<Type> otvars = ot.getTypeArguments(); 1707 Type mtres = mt.getReturnType(); 1708 Type otres = types.subst(ot.getReturnType(), otvars, mtvars); 1709 1710 overrideWarner.clear(); 1711 boolean resultTypesOK = 1712 types.returnTypeSubstitutable(mt, ot, otres, overrideWarner); 1713 if (!resultTypesOK) { 1714 log.error(TreeInfo.diagnosticPositionFor(m, tree), 1715 "override.incompatible.ret", 1716 cannotOverride(m, other), 1717 mtres, otres); 1718 m.flags_field |= BAD_OVERRIDE; 1719 return; 1720 } else if (overrideWarner.hasNonSilentLint(LintCategory.UNCHECKED)) { 1721 warnUnchecked(TreeInfo.diagnosticPositionFor(m, tree), 1722 "override.unchecked.ret", 1723 uncheckedOverrides(m, other), 1724 mtres, otres); 1725 } 1726 1727 // Error if overriding method throws an exception not reported 1728 // by overridden method. 1729 List<Type> otthrown = types.subst(ot.getThrownTypes(), otvars, mtvars); 1730 List<Type> unhandledErased = unhandled(mt.getThrownTypes(), types.erasure(otthrown)); 1731 List<Type> unhandledUnerased = unhandled(mt.getThrownTypes(), otthrown); 1732 if (unhandledErased.nonEmpty()) { 1733 log.error(TreeInfo.diagnosticPositionFor(m, tree), 1734 "override.meth.doesnt.throw", 1735 cannotOverride(m, other), 1736 unhandledUnerased.head); 1737 m.flags_field |= BAD_OVERRIDE; 1738 return; 1739 } 1740 else if (unhandledUnerased.nonEmpty()) { 1741 warnUnchecked(TreeInfo.diagnosticPositionFor(m, tree), 1742 "override.unchecked.thrown", 1743 cannotOverride(m, other), 1744 unhandledUnerased.head); 1745 return; 1746 } 1747 1748 // Optional warning if varargs don't agree 1749 if ((((m.flags() ^ other.flags()) & Flags.VARARGS) != 0) 1750 && lint.isEnabled(LintCategory.OVERRIDES)) { 1751 log.warning(TreeInfo.diagnosticPositionFor(m, tree), 1752 ((m.flags() & Flags.VARARGS) != 0) 1753 ? "override.varargs.missing" 1754 : "override.varargs.extra", 1755 varargsOverrides(m, other)); 1756 } 1757 1758 // Warn if instance method overrides bridge method (compiler spec ??) 1759 if ((other.flags() & BRIDGE) != 0) { 1760 log.warning(TreeInfo.diagnosticPositionFor(m, tree), "override.bridge", 1761 uncheckedOverrides(m, other)); 1762 } 1763 1764 // Warn if a deprecated method overridden by a non-deprecated one. 1765 if (!isDeprecatedOverrideIgnorable(other, origin)) { 1766 Lint prevLint = setLint(lint.augment(m)); 1767 try { 1768 checkDeprecated(TreeInfo.diagnosticPositionFor(m, tree), m, other); 1769 } finally { 1770 setLint(prevLint); 1771 } 1772 } 1773 } 1774 // where 1775 private boolean isDeprecatedOverrideIgnorable(MethodSymbol m, ClassSymbol origin) { 1776 // If the method, m, is defined in an interface, then ignore the issue if the method 1777 // is only inherited via a supertype and also implemented in the supertype, 1778 // because in that case, we will rediscover the issue when examining the method 1779 // in the supertype. 1780 // If the method, m, is not defined in an interface, then the only time we need to 1781 // address the issue is when the method is the supertype implemementation: any other 1782 // case, we will have dealt with when examining the supertype classes 1783 ClassSymbol mc = m.enclClass(); 1784 Type st = types.supertype(origin.type); 1785 if (!st.hasTag(CLASS)) 1786 return true; 1787 MethodSymbol stimpl = m.implementation((ClassSymbol)st.tsym, types, false); 1788 1789 if (mc != null && ((mc.flags() & INTERFACE) != 0)) { 1790 List<Type> intfs = types.interfaces(origin.type); 1791 return (intfs.contains(mc.type) ? false : (stimpl != null)); 1792 } 1793 else 1794 return (stimpl != m); 1795 } 1796 1797 1798 // used to check if there were any unchecked conversions 1799 Warner overrideWarner = new Warner(); 1800 1801 /** Check that a class does not inherit two concrete methods 1802 * with the same signature. 1803 * @param pos Position to be used for error reporting. 1804 * @param site The class type to be checked. 1805 */ 1806 public void checkCompatibleConcretes(DiagnosticPosition pos, Type site) { 1807 Type sup = types.supertype(site); 1808 if (!sup.hasTag(CLASS)) return; 1809 1810 for (Type t1 = sup; 1811 t1.hasTag(CLASS) && t1.tsym.type.isParameterized(); 1812 t1 = types.supertype(t1)) { 1813 for (Symbol s1 : t1.tsym.members().getSymbols(NON_RECURSIVE)) { 1814 if (s1.kind != MTH || 1815 (s1.flags() & (STATIC|SYNTHETIC|BRIDGE)) != 0 || 1816 !s1.isInheritedIn(site.tsym, types) || 1817 ((MethodSymbol)s1).implementation(site.tsym, 1818 types, 1819 true) != s1) 1820 continue; 1821 Type st1 = types.memberType(t1, s1); 1822 int s1ArgsLength = st1.getParameterTypes().length(); 1823 if (st1 == s1.type) continue; 1824 1825 for (Type t2 = sup; 1826 t2.hasTag(CLASS); 1827 t2 = types.supertype(t2)) { 1828 for (Symbol s2 : t2.tsym.members().getSymbolsByName(s1.name)) { 1829 if (s2 == s1 || 1830 s2.kind != MTH || 1831 (s2.flags() & (STATIC|SYNTHETIC|BRIDGE)) != 0 || 1832 s2.type.getParameterTypes().length() != s1ArgsLength || 1833 !s2.isInheritedIn(site.tsym, types) || 1834 ((MethodSymbol)s2).implementation(site.tsym, 1835 types, 1836 true) != s2) 1837 continue; 1838 Type st2 = types.memberType(t2, s2); 1839 if (types.overrideEquivalent(st1, st2)) 1840 log.error(pos, "concrete.inheritance.conflict", 1841 s1, t1, s2, t2, sup); 1842 } 1843 } 1844 } 1845 } 1846 } 1847 1848 /** Check that classes (or interfaces) do not each define an abstract 1849 * method with same name and arguments but incompatible return types. 1850 * @param pos Position to be used for error reporting. 1851 * @param t1 The first argument type. 1852 * @param t2 The second argument type. 1853 */ 1854 public boolean checkCompatibleAbstracts(DiagnosticPosition pos, 1855 Type t1, 1856 Type t2, 1857 Type site) { 1858 if ((site.tsym.flags() & COMPOUND) != 0) { 1859 // special case for intersections: need to eliminate wildcards in supertypes 1860 t1 = types.capture(t1); 1861 t2 = types.capture(t2); 1862 } 1863 return firstIncompatibility(pos, t1, t2, site) == null; 1864 } 1865 1866 /** Return the first method which is defined with same args 1867 * but different return types in two given interfaces, or null if none 1868 * exists. 1869 * @param t1 The first type. 1870 * @param t2 The second type. 1871 * @param site The most derived type. 1872 * @returns symbol from t2 that conflicts with one in t1. 1873 */ 1874 private Symbol firstIncompatibility(DiagnosticPosition pos, Type t1, Type t2, Type site) { 1875 Map<TypeSymbol,Type> interfaces1 = new HashMap<>(); 1876 closure(t1, interfaces1); 1877 Map<TypeSymbol,Type> interfaces2; 1878 if (t1 == t2) 1879 interfaces2 = interfaces1; 1880 else 1881 closure(t2, interfaces1, interfaces2 = new HashMap<>()); 1882 1883 for (Type t3 : interfaces1.values()) { 1884 for (Type t4 : interfaces2.values()) { 1885 Symbol s = firstDirectIncompatibility(pos, t3, t4, site); 1886 if (s != null) return s; 1887 } 1888 } 1889 return null; 1890 } 1891 1892 /** Compute all the supertypes of t, indexed by type symbol. */ 1893 private void closure(Type t, Map<TypeSymbol,Type> typeMap) { 1894 if (!t.hasTag(CLASS)) return; 1895 if (typeMap.put(t.tsym, t) == null) { 1896 closure(types.supertype(t), typeMap); 1897 for (Type i : types.interfaces(t)) 1898 closure(i, typeMap); 1899 } 1900 } 1901 1902 /** Compute all the supertypes of t, indexed by type symbol (except thise in typesSkip). */ 1903 private void closure(Type t, Map<TypeSymbol,Type> typesSkip, Map<TypeSymbol,Type> typeMap) { 1904 if (!t.hasTag(CLASS)) return; 1905 if (typesSkip.get(t.tsym) != null) return; 1906 if (typeMap.put(t.tsym, t) == null) { 1907 closure(types.supertype(t), typesSkip, typeMap); 1908 for (Type i : types.interfaces(t)) 1909 closure(i, typesSkip, typeMap); 1910 } 1911 } 1912 1913 /** Return the first method in t2 that conflicts with a method from t1. */ 1914 private Symbol firstDirectIncompatibility(DiagnosticPosition pos, Type t1, Type t2, Type site) { 1915 for (Symbol s1 : t1.tsym.members().getSymbols(NON_RECURSIVE)) { 1916 Type st1 = null; 1917 if (s1.kind != MTH || !s1.isInheritedIn(site.tsym, types) || 1918 (s1.flags() & SYNTHETIC) != 0) continue; 1919 Symbol impl = ((MethodSymbol)s1).implementation(site.tsym, types, false); 1920 if (impl != null && (impl.flags() & ABSTRACT) == 0) continue; 1921 for (Symbol s2 : t2.tsym.members().getSymbolsByName(s1.name)) { 1922 if (s1 == s2) continue; 1923 if (s2.kind != MTH || !s2.isInheritedIn(site.tsym, types) || 1924 (s2.flags() & SYNTHETIC) != 0) continue; 1925 if (st1 == null) st1 = types.memberType(t1, s1); 1926 Type st2 = types.memberType(t2, s2); 1927 if (types.overrideEquivalent(st1, st2)) { 1928 List<Type> tvars1 = st1.getTypeArguments(); 1929 List<Type> tvars2 = st2.getTypeArguments(); 1930 Type rt1 = st1.getReturnType(); 1931 Type rt2 = types.subst(st2.getReturnType(), tvars2, tvars1); 1932 boolean compat = 1933 types.isSameType(rt1, rt2) || 1934 !rt1.isPrimitiveOrVoid() && 1935 !rt2.isPrimitiveOrVoid() && 1936 (types.covariantReturnType(rt1, rt2, types.noWarnings) || 1937 types.covariantReturnType(rt2, rt1, types.noWarnings)) || 1938 checkCommonOverriderIn(s1,s2,site); 1939 if (!compat) { 1940 log.error(pos, "types.incompatible.diff.ret", 1941 t1, t2, s2.name + 1942 "(" + types.memberType(t2, s2).getParameterTypes() + ")"); 1943 return s2; 1944 } 1945 } else if (checkNameClash((ClassSymbol)site.tsym, s1, s2) && 1946 !checkCommonOverriderIn(s1, s2, site)) { 1947 log.error(pos, 1948 "name.clash.same.erasure.no.override", 1949 s1, s1.location(), 1950 s2, s2.location()); 1951 return s2; 1952 } 1953 } 1954 } 1955 return null; 1956 } 1957 //WHERE 1958 boolean checkCommonOverriderIn(Symbol s1, Symbol s2, Type site) { 1959 Map<TypeSymbol,Type> supertypes = new HashMap<>(); 1960 Type st1 = types.memberType(site, s1); 1961 Type st2 = types.memberType(site, s2); 1962 closure(site, supertypes); 1963 for (Type t : supertypes.values()) { 1964 for (Symbol s3 : t.tsym.members().getSymbolsByName(s1.name)) { 1965 if (s3 == s1 || s3 == s2 || s3.kind != MTH || (s3.flags() & (BRIDGE|SYNTHETIC)) != 0) continue; 1966 Type st3 = types.memberType(site,s3); 1967 if (types.overrideEquivalent(st3, st1) && 1968 types.overrideEquivalent(st3, st2) && 1969 types.returnTypeSubstitutable(st3, st1) && 1970 types.returnTypeSubstitutable(st3, st2)) { 1971 return true; 1972 } 1973 } 1974 } 1975 return false; 1976 } 1977 1978 /** Check that a given method conforms with any method it overrides. 1979 * @param tree The tree from which positions are extracted 1980 * for errors. 1981 * @param m The overriding method. 1982 */ 1983 void checkOverride(Env<AttrContext> env, JCMethodDecl tree, MethodSymbol m) { 1984 ClassSymbol origin = (ClassSymbol)m.owner; 1985 if ((origin.flags() & ENUM) != 0 && names.finalize.equals(m.name)) 1986 if (m.overrides(syms.enumFinalFinalize, origin, types, false)) { 1987 log.error(tree.pos(), "enum.no.finalize"); 1988 return; 1989 } 1990 for (Type t = origin.type; t.hasTag(CLASS); 1991 t = types.supertype(t)) { 1992 if (t != origin.type) { 1993 checkOverride(tree, t, origin, m); 1994 } 1995 for (Type t2 : types.interfaces(t)) { 1996 checkOverride(tree, t2, origin, m); 1997 } 1998 } 1999 2000 // Check if this method must override a super method due to being annotated with @Override 2001 // or by virtue of being a member of a diamond inferred anonymous class. Latter case is to 2002 // be treated "as if as they were annotated" with @Override. 2003 boolean mustOverride = m.attribute(syms.overrideType.tsym) != null || 2004 (env.info.isAnonymousDiamond && !m.isConstructor() && !m.isPrivate()); 2005 if (mustOverride && !isOverrider(m)) { 2006 DiagnosticPosition pos = tree.pos(); 2007 for (JCAnnotation a : tree.getModifiers().annotations) { 2008 if (a.annotationType.type.tsym == syms.overrideType.tsym) { 2009 pos = a.pos(); 2010 break; 2011 } 2012 } 2013 log.error(pos, "method.does.not.override.superclass"); 2014 } 2015 } 2016 2017 void checkOverride(JCTree tree, Type site, ClassSymbol origin, MethodSymbol m) { 2018 TypeSymbol c = site.tsym; 2019 for (Symbol sym : c.members().getSymbolsByName(m.name)) { 2020 if (m.overrides(sym, origin, types, false)) { 2021 if ((sym.flags() & ABSTRACT) == 0) { 2022 checkOverride(tree, m, (MethodSymbol)sym, origin); 2023 } 2024 } 2025 } 2026 } 2027 2028 private Filter<Symbol> equalsHasCodeFilter = new Filter<Symbol>() { 2029 public boolean accepts(Symbol s) { 2030 return MethodSymbol.implementation_filter.accepts(s) && 2031 (s.flags() & BAD_OVERRIDE) == 0; 2032 2033 } 2034 }; 2035 2036 public void checkClassOverrideEqualsAndHashIfNeeded(DiagnosticPosition pos, 2037 ClassSymbol someClass) { 2038 /* At present, annotations cannot possibly have a method that is override 2039 * equivalent with Object.equals(Object) but in any case the condition is 2040 * fine for completeness. 2041 */ 2042 if (someClass == (ClassSymbol)syms.objectType.tsym || 2043 someClass.isInterface() || someClass.isEnum() || 2044 (someClass.flags() & ANNOTATION) != 0 || 2045 (someClass.flags() & ABSTRACT) != 0) return; 2046 //anonymous inner classes implementing interfaces need especial treatment 2047 if (someClass.isAnonymous()) { 2048 List<Type> interfaces = types.interfaces(someClass.type); 2049 if (interfaces != null && !interfaces.isEmpty() && 2050 interfaces.head.tsym == syms.comparatorType.tsym) return; 2051 } 2052 checkClassOverrideEqualsAndHash(pos, someClass); 2053 } 2054 2055 private void checkClassOverrideEqualsAndHash(DiagnosticPosition pos, 2056 ClassSymbol someClass) { 2057 if (lint.isEnabled(LintCategory.OVERRIDES)) { 2058 MethodSymbol equalsAtObject = (MethodSymbol)syms.objectType 2059 .tsym.members().findFirst(names.equals); 2060 MethodSymbol hashCodeAtObject = (MethodSymbol)syms.objectType 2061 .tsym.members().findFirst(names.hashCode); 2062 boolean overridesEquals = types.implementation(equalsAtObject, 2063 someClass, false, equalsHasCodeFilter).owner == someClass; 2064 boolean overridesHashCode = types.implementation(hashCodeAtObject, 2065 someClass, false, equalsHasCodeFilter) != hashCodeAtObject; 2066 2067 if (overridesEquals && !overridesHashCode) { 2068 log.warning(LintCategory.OVERRIDES, pos, 2069 "override.equals.but.not.hashcode", someClass); 2070 } 2071 } 2072 } 2073 2074 private boolean checkNameClash(ClassSymbol origin, Symbol s1, Symbol s2) { 2075 ClashFilter cf = new ClashFilter(origin.type); 2076 return (cf.accepts(s1) && 2077 cf.accepts(s2) && 2078 types.hasSameArgs(s1.erasure(types), s2.erasure(types))); 2079 } 2080 2081 2082 /** Check that all abstract members of given class have definitions. 2083 * @param pos Position to be used for error reporting. 2084 * @param c The class. 2085 */ 2086 void checkAllDefined(DiagnosticPosition pos, ClassSymbol c) { 2087 MethodSymbol undef = types.firstUnimplementedAbstract(c); 2088 if (undef != null) { 2089 MethodSymbol undef1 = 2090 new MethodSymbol(undef.flags(), undef.name, 2091 types.memberType(c.type, undef), undef.owner); 2092 log.error(pos, "does.not.override.abstract", 2093 c, undef1, undef1.location()); 2094 } 2095 } 2096 2097 void checkNonCyclicDecl(JCClassDecl tree) { 2098 CycleChecker cc = new CycleChecker(); 2099 cc.scan(tree); 2100 if (!cc.errorFound && !cc.partialCheck) { 2101 tree.sym.flags_field |= ACYCLIC; 2102 } 2103 } 2104 2105 class CycleChecker extends TreeScanner { 2106 2107 List<Symbol> seenClasses = List.nil(); 2108 boolean errorFound = false; 2109 boolean partialCheck = false; 2110 2111 private void checkSymbol(DiagnosticPosition pos, Symbol sym) { 2112 if (sym != null && sym.kind == TYP) { 2113 Env<AttrContext> classEnv = enter.getEnv((TypeSymbol)sym); 2114 if (classEnv != null) { 2115 DiagnosticSource prevSource = log.currentSource(); 2116 try { 2117 log.useSource(classEnv.toplevel.sourcefile); 2118 scan(classEnv.tree); 2119 } 2120 finally { 2121 log.useSource(prevSource.getFile()); 2122 } 2123 } else if (sym.kind == TYP) { 2124 checkClass(pos, sym, List.<JCTree>nil()); 2125 } 2126 } else { 2127 //not completed yet 2128 partialCheck = true; 2129 } 2130 } 2131 2132 @Override 2133 public void visitSelect(JCFieldAccess tree) { 2134 super.visitSelect(tree); 2135 checkSymbol(tree.pos(), tree.sym); 2136 } 2137 2138 @Override 2139 public void visitIdent(JCIdent tree) { 2140 checkSymbol(tree.pos(), tree.sym); 2141 } 2142 2143 @Override 2144 public void visitTypeApply(JCTypeApply tree) { 2145 scan(tree.clazz); 2146 } 2147 2148 @Override 2149 public void visitTypeArray(JCArrayTypeTree tree) { 2150 scan(tree.elemtype); 2151 } 2152 2153 @Override 2154 public void visitClassDef(JCClassDecl tree) { 2155 List<JCTree> supertypes = List.nil(); 2156 if (tree.getExtendsClause() != null) { 2157 supertypes = supertypes.prepend(tree.getExtendsClause()); 2158 } 2159 if (tree.getImplementsClause() != null) { 2160 for (JCTree intf : tree.getImplementsClause()) { 2161 supertypes = supertypes.prepend(intf); 2162 } 2163 } 2164 checkClass(tree.pos(), tree.sym, supertypes); 2165 } 2166 2167 void checkClass(DiagnosticPosition pos, Symbol c, List<JCTree> supertypes) { 2168 if ((c.flags_field & ACYCLIC) != 0) 2169 return; 2170 if (seenClasses.contains(c)) { 2171 errorFound = true; 2172 noteCyclic(pos, (ClassSymbol)c); 2173 } else if (!c.type.isErroneous()) { 2174 try { 2175 seenClasses = seenClasses.prepend(c); 2176 if (c.type.hasTag(CLASS)) { 2177 if (supertypes.nonEmpty()) { 2178 scan(supertypes); 2179 } 2180 else { 2181 ClassType ct = (ClassType)c.type; 2182 if (ct.supertype_field == null || 2183 ct.interfaces_field == null) { 2184 //not completed yet 2185 partialCheck = true; 2186 return; 2187 } 2188 checkSymbol(pos, ct.supertype_field.tsym); 2189 for (Type intf : ct.interfaces_field) { 2190 checkSymbol(pos, intf.tsym); 2191 } 2192 } 2193 if (c.owner.kind == TYP) { 2194 checkSymbol(pos, c.owner); 2195 } 2196 } 2197 } finally { 2198 seenClasses = seenClasses.tail; 2199 } 2200 } 2201 } 2202 } 2203 2204 /** Check for cyclic references. Issue an error if the 2205 * symbol of the type referred to has a LOCKED flag set. 2206 * 2207 * @param pos Position to be used for error reporting. 2208 * @param t The type referred to. 2209 */ 2210 void checkNonCyclic(DiagnosticPosition pos, Type t) { 2211 checkNonCyclicInternal(pos, t); 2212 } 2213 2214 2215 void checkNonCyclic(DiagnosticPosition pos, TypeVar t) { 2216 checkNonCyclic1(pos, t, List.<TypeVar>nil()); 2217 } 2218 2219 private void checkNonCyclic1(DiagnosticPosition pos, Type t, List<TypeVar> seen) { 2220 final TypeVar tv; 2221 if (t.hasTag(TYPEVAR) && (t.tsym.flags() & UNATTRIBUTED) != 0) 2222 return; 2223 if (seen.contains(t)) { 2224 tv = (TypeVar)t; 2225 tv.bound = types.createErrorType(t); 2226 log.error(pos, "cyclic.inheritance", t); 2227 } else if (t.hasTag(TYPEVAR)) { 2228 tv = (TypeVar)t; 2229 seen = seen.prepend(tv); 2230 for (Type b : types.getBounds(tv)) 2231 checkNonCyclic1(pos, b, seen); 2232 } 2233 } 2234 2235 /** Check for cyclic references. Issue an error if the 2236 * symbol of the type referred to has a LOCKED flag set. 2237 * 2238 * @param pos Position to be used for error reporting. 2239 * @param t The type referred to. 2240 * @returns True if the check completed on all attributed classes 2241 */ 2242 private boolean checkNonCyclicInternal(DiagnosticPosition pos, Type t) { 2243 boolean complete = true; // was the check complete? 2244 //- System.err.println("checkNonCyclicInternal("+t+");");//DEBUG 2245 Symbol c = t.tsym; 2246 if ((c.flags_field & ACYCLIC) != 0) return true; 2247 2248 if ((c.flags_field & LOCKED) != 0) { 2249 noteCyclic(pos, (ClassSymbol)c); 2250 } else if (!c.type.isErroneous()) { 2251 try { 2252 c.flags_field |= LOCKED; 2253 if (c.type.hasTag(CLASS)) { 2254 ClassType clazz = (ClassType)c.type; 2255 if (clazz.interfaces_field != null) 2256 for (List<Type> l=clazz.interfaces_field; l.nonEmpty(); l=l.tail) 2257 complete &= checkNonCyclicInternal(pos, l.head); 2258 if (clazz.supertype_field != null) { 2259 Type st = clazz.supertype_field; 2260 if (st != null && st.hasTag(CLASS)) 2261 complete &= checkNonCyclicInternal(pos, st); 2262 } 2263 if (c.owner.kind == TYP) 2264 complete &= checkNonCyclicInternal(pos, c.owner.type); 2265 } 2266 } finally { 2267 c.flags_field &= ~LOCKED; 2268 } 2269 } 2270 if (complete) 2271 complete = ((c.flags_field & UNATTRIBUTED) == 0) && c.isCompleted(); 2272 if (complete) c.flags_field |= ACYCLIC; 2273 return complete; 2274 } 2275 2276 /** Note that we found an inheritance cycle. */ 2277 private void noteCyclic(DiagnosticPosition pos, ClassSymbol c) { 2278 log.error(pos, "cyclic.inheritance", c); 2279 for (List<Type> l=types.interfaces(c.type); l.nonEmpty(); l=l.tail) 2280 l.head = types.createErrorType((ClassSymbol)l.head.tsym, Type.noType); 2281 Type st = types.supertype(c.type); 2282 if (st.hasTag(CLASS)) 2283 ((ClassType)c.type).supertype_field = types.createErrorType((ClassSymbol)st.tsym, Type.noType); 2284 c.type = types.createErrorType(c, c.type); 2285 c.flags_field |= ACYCLIC; 2286 } 2287 2288 /** Check that all methods which implement some 2289 * method conform to the method they implement. 2290 * @param tree The class definition whose members are checked. 2291 */ 2292 void checkImplementations(JCClassDecl tree) { 2293 checkImplementations(tree, tree.sym, tree.sym); 2294 } 2295 //where 2296 /** Check that all methods which implement some 2297 * method in `ic' conform to the method they implement. 2298 */ 2299 void checkImplementations(JCTree tree, ClassSymbol origin, ClassSymbol ic) { 2300 for (List<Type> l = types.closure(ic.type); l.nonEmpty(); l = l.tail) { 2301 ClassSymbol lc = (ClassSymbol)l.head.tsym; 2302 if ((lc.flags() & ABSTRACT) != 0) { 2303 for (Symbol sym : lc.members().getSymbols(NON_RECURSIVE)) { 2304 if (sym.kind == MTH && 2305 (sym.flags() & (STATIC|ABSTRACT)) == ABSTRACT) { 2306 MethodSymbol absmeth = (MethodSymbol)sym; 2307 MethodSymbol implmeth = absmeth.implementation(origin, types, false); 2308 if (implmeth != null && implmeth != absmeth && 2309 (implmeth.owner.flags() & INTERFACE) == 2310 (origin.flags() & INTERFACE)) { 2311 // don't check if implmeth is in a class, yet 2312 // origin is an interface. This case arises only 2313 // if implmeth is declared in Object. The reason is 2314 // that interfaces really don't inherit from 2315 // Object it's just that the compiler represents 2316 // things that way. 2317 checkOverride(tree, implmeth, absmeth, origin); 2318 } 2319 } 2320 } 2321 } 2322 } 2323 } 2324 2325 /** Check that all abstract methods implemented by a class are 2326 * mutually compatible. 2327 * @param pos Position to be used for error reporting. 2328 * @param c The class whose interfaces are checked. 2329 */ 2330 void checkCompatibleSupertypes(DiagnosticPosition pos, Type c) { 2331 List<Type> supertypes = types.interfaces(c); 2332 Type supertype = types.supertype(c); 2333 if (supertype.hasTag(CLASS) && 2334 (supertype.tsym.flags() & ABSTRACT) != 0) 2335 supertypes = supertypes.prepend(supertype); 2336 for (List<Type> l = supertypes; l.nonEmpty(); l = l.tail) { 2337 if (!l.head.getTypeArguments().isEmpty() && 2338 !checkCompatibleAbstracts(pos, l.head, l.head, c)) 2339 return; 2340 for (List<Type> m = supertypes; m != l; m = m.tail) 2341 if (!checkCompatibleAbstracts(pos, l.head, m.head, c)) 2342 return; 2343 } 2344 checkCompatibleConcretes(pos, c); 2345 } 2346 2347 void checkConflicts(DiagnosticPosition pos, Symbol sym, TypeSymbol c) { 2348 for (Type ct = c.type; ct != Type.noType ; ct = types.supertype(ct)) { 2349 for (Symbol sym2 : ct.tsym.members().getSymbolsByName(sym.name, NON_RECURSIVE)) { 2350 // VM allows methods and variables with differing types 2351 if (sym.kind == sym2.kind && 2352 types.isSameType(types.erasure(sym.type), types.erasure(sym2.type)) && 2353 sym != sym2 && 2354 (sym.flags() & Flags.SYNTHETIC) != (sym2.flags() & Flags.SYNTHETIC) && 2355 (sym.flags() & IPROXY) == 0 && (sym2.flags() & IPROXY) == 0 && 2356 (sym.flags() & BRIDGE) == 0 && (sym2.flags() & BRIDGE) == 0) { 2357 syntheticError(pos, (sym2.flags() & SYNTHETIC) == 0 ? sym2 : sym); 2358 return; 2359 } 2360 } 2361 } 2362 } 2363 2364 /** Check that all non-override equivalent methods accessible from 'site' 2365 * are mutually compatible (JLS 8.4.8/9.4.1). 2366 * 2367 * @param pos Position to be used for error reporting. 2368 * @param site The class whose methods are checked. 2369 * @param sym The method symbol to be checked. 2370 */ 2371 void checkOverrideClashes(DiagnosticPosition pos, Type site, MethodSymbol sym) { 2372 ClashFilter cf = new ClashFilter(site); 2373 //for each method m1 that is overridden (directly or indirectly) 2374 //by method 'sym' in 'site'... 2375 2376 List<MethodSymbol> potentiallyAmbiguousList = List.nil(); 2377 boolean overridesAny = false; 2378 for (Symbol m1 : types.membersClosure(site, false).getSymbolsByName(sym.name, cf)) { 2379 if (!sym.overrides(m1, site.tsym, types, false)) { 2380 if (m1 == sym) { 2381 continue; 2382 } 2383 2384 if (!overridesAny) { 2385 potentiallyAmbiguousList = potentiallyAmbiguousList.prepend((MethodSymbol)m1); 2386 } 2387 continue; 2388 } 2389 2390 if (m1 != sym) { 2391 overridesAny = true; 2392 potentiallyAmbiguousList = List.nil(); 2393 } 2394 2395 //...check each method m2 that is a member of 'site' 2396 for (Symbol m2 : types.membersClosure(site, false).getSymbolsByName(sym.name, cf)) { 2397 if (m2 == m1) continue; 2398 //if (i) the signature of 'sym' is not a subsignature of m1 (seen as 2399 //a member of 'site') and (ii) m1 has the same erasure as m2, issue an error 2400 if (!types.isSubSignature(sym.type, types.memberType(site, m2), allowStrictMethodClashCheck) && 2401 types.hasSameArgs(m2.erasure(types), m1.erasure(types))) { 2402 sym.flags_field |= CLASH; 2403 String key = m1 == sym ? 2404 "name.clash.same.erasure.no.override" : 2405 "name.clash.same.erasure.no.override.1"; 2406 log.error(pos, 2407 key, 2408 sym, sym.location(), 2409 m2, m2.location(), 2410 m1, m1.location()); 2411 return; 2412 } 2413 } 2414 } 2415 2416 if (!overridesAny) { 2417 for (MethodSymbol m: potentiallyAmbiguousList) { 2418 checkPotentiallyAmbiguousOverloads(pos, site, sym, m); 2419 } 2420 } 2421 } 2422 2423 /** Check that all static methods accessible from 'site' are 2424 * mutually compatible (JLS 8.4.8). 2425 * 2426 * @param pos Position to be used for error reporting. 2427 * @param site The class whose methods are checked. 2428 * @param sym The method symbol to be checked. 2429 */ 2430 void checkHideClashes(DiagnosticPosition pos, Type site, MethodSymbol sym) { 2431 ClashFilter cf = new ClashFilter(site); 2432 //for each method m1 that is a member of 'site'... 2433 for (Symbol s : types.membersClosure(site, true).getSymbolsByName(sym.name, cf)) { 2434 //if (i) the signature of 'sym' is not a subsignature of m1 (seen as 2435 //a member of 'site') and (ii) 'sym' has the same erasure as m1, issue an error 2436 if (!types.isSubSignature(sym.type, types.memberType(site, s), allowStrictMethodClashCheck)) { 2437 if (types.hasSameArgs(s.erasure(types), sym.erasure(types))) { 2438 log.error(pos, 2439 "name.clash.same.erasure.no.hide", 2440 sym, sym.location(), 2441 s, s.location()); 2442 return; 2443 } else { 2444 checkPotentiallyAmbiguousOverloads(pos, site, sym, (MethodSymbol)s); 2445 } 2446 } 2447 } 2448 } 2449 2450 //where 2451 private class ClashFilter implements Filter<Symbol> { 2452 2453 Type site; 2454 2455 ClashFilter(Type site) { 2456 this.site = site; 2457 } 2458 2459 boolean shouldSkip(Symbol s) { 2460 return (s.flags() & CLASH) != 0 && 2461 s.owner == site.tsym; 2462 } 2463 2464 public boolean accepts(Symbol s) { 2465 return s.kind == MTH && 2466 (s.flags() & SYNTHETIC) == 0 && 2467 !shouldSkip(s) && 2468 s.isInheritedIn(site.tsym, types) && 2469 !s.isConstructor(); 2470 } 2471 } 2472 2473 void checkDefaultMethodClashes(DiagnosticPosition pos, Type site) { 2474 DefaultMethodClashFilter dcf = new DefaultMethodClashFilter(site); 2475 for (Symbol m : types.membersClosure(site, false).getSymbols(dcf)) { 2476 Assert.check(m.kind == MTH); 2477 List<MethodSymbol> prov = types.interfaceCandidates(site, (MethodSymbol)m); 2478 if (prov.size() > 1) { 2479 ListBuffer<Symbol> abstracts = new ListBuffer<>(); 2480 ListBuffer<Symbol> defaults = new ListBuffer<>(); 2481 for (MethodSymbol provSym : prov) { 2482 if ((provSym.flags() & DEFAULT) != 0) { 2483 defaults = defaults.append(provSym); 2484 } else if ((provSym.flags() & ABSTRACT) != 0) { 2485 abstracts = abstracts.append(provSym); 2486 } 2487 if (defaults.nonEmpty() && defaults.size() + abstracts.size() >= 2) { 2488 //strong semantics - issue an error if two sibling interfaces 2489 //have two override-equivalent defaults - or if one is abstract 2490 //and the other is default 2491 String errKey; 2492 Symbol s1 = defaults.first(); 2493 Symbol s2; 2494 if (defaults.size() > 1) { 2495 errKey = "types.incompatible.unrelated.defaults"; 2496 s2 = defaults.toList().tail.head; 2497 } else { 2498 errKey = "types.incompatible.abstract.default"; 2499 s2 = abstracts.first(); 2500 } 2501 log.error(pos, errKey, 2502 Kinds.kindName(site.tsym), site, 2503 m.name, types.memberType(site, m).getParameterTypes(), 2504 s1.location(), s2.location()); 2505 break; 2506 } 2507 } 2508 } 2509 } 2510 } 2511 2512 //where 2513 private class DefaultMethodClashFilter implements Filter<Symbol> { 2514 2515 Type site; 2516 2517 DefaultMethodClashFilter(Type site) { 2518 this.site = site; 2519 } 2520 2521 public boolean accepts(Symbol s) { 2522 return s.kind == MTH && 2523 (s.flags() & DEFAULT) != 0 && 2524 s.isInheritedIn(site.tsym, types) && 2525 !s.isConstructor(); 2526 } 2527 } 2528 2529 /** 2530 * Report warnings for potentially ambiguous method declarations. Two declarations 2531 * are potentially ambiguous if they feature two unrelated functional interface 2532 * in same argument position (in which case, a call site passing an implicit 2533 * lambda would be ambiguous). 2534 */ 2535 void checkPotentiallyAmbiguousOverloads(DiagnosticPosition pos, Type site, 2536 MethodSymbol msym1, MethodSymbol msym2) { 2537 if (msym1 != msym2 && 2538 allowDefaultMethods && 2539 lint.isEnabled(LintCategory.OVERLOADS) && 2540 (msym1.flags() & POTENTIALLY_AMBIGUOUS) == 0 && 2541 (msym2.flags() & POTENTIALLY_AMBIGUOUS) == 0) { 2542 Type mt1 = types.memberType(site, msym1); 2543 Type mt2 = types.memberType(site, msym2); 2544 //if both generic methods, adjust type variables 2545 if (mt1.hasTag(FORALL) && mt2.hasTag(FORALL) && 2546 types.hasSameBounds((ForAll)mt1, (ForAll)mt2)) { 2547 mt2 = types.subst(mt2, ((ForAll)mt2).tvars, ((ForAll)mt1).tvars); 2548 } 2549 //expand varargs methods if needed 2550 int maxLength = Math.max(mt1.getParameterTypes().length(), mt2.getParameterTypes().length()); 2551 List<Type> args1 = rs.adjustArgs(mt1.getParameterTypes(), msym1, maxLength, true); 2552 List<Type> args2 = rs.adjustArgs(mt2.getParameterTypes(), msym2, maxLength, true); 2553 //if arities don't match, exit 2554 if (args1.length() != args2.length()) return; 2555 boolean potentiallyAmbiguous = false; 2556 while (args1.nonEmpty() && args2.nonEmpty()) { 2557 Type s = args1.head; 2558 Type t = args2.head; 2559 if (!types.isSubtype(t, s) && !types.isSubtype(s, t)) { 2560 if (types.isFunctionalInterface(s) && types.isFunctionalInterface(t) && 2561 types.findDescriptorType(s).getParameterTypes().length() > 0 && 2562 types.findDescriptorType(s).getParameterTypes().length() == 2563 types.findDescriptorType(t).getParameterTypes().length()) { 2564 potentiallyAmbiguous = true; 2565 } else { 2566 break; 2567 } 2568 } 2569 args1 = args1.tail; 2570 args2 = args2.tail; 2571 } 2572 if (potentiallyAmbiguous) { 2573 //we found two incompatible functional interfaces with same arity 2574 //this means a call site passing an implicit lambda would be ambigiuous 2575 msym1.flags_field |= POTENTIALLY_AMBIGUOUS; 2576 msym2.flags_field |= POTENTIALLY_AMBIGUOUS; 2577 log.warning(LintCategory.OVERLOADS, pos, "potentially.ambiguous.overload", 2578 msym1, msym1.location(), 2579 msym2, msym2.location()); 2580 return; 2581 } 2582 } 2583 } 2584 2585 void checkElemAccessFromSerializableLambda(final JCTree tree) { 2586 if (warnOnAccessToSensitiveMembers) { 2587 Symbol sym = TreeInfo.symbol(tree); 2588 if (!sym.kind.matches(KindSelector.VAL_MTH)) { 2589 return; 2590 } 2591 2592 if (sym.kind == VAR) { 2593 if ((sym.flags() & PARAMETER) != 0 || 2594 sym.isLocal() || 2595 sym.name == names._this || 2596 sym.name == names._super) { 2597 return; 2598 } 2599 } 2600 2601 if (!types.isSubtype(sym.owner.type, syms.serializableType) && 2602 isEffectivelyNonPublic(sym)) { 2603 log.warning(tree.pos(), 2604 "access.to.sensitive.member.from.serializable.element", sym); 2605 } 2606 } 2607 } 2608 2609 private boolean isEffectivelyNonPublic(Symbol sym) { 2610 if (sym.packge() == syms.rootPackage) { 2611 return false; 2612 } 2613 2614 while (sym.kind != PCK) { 2615 if ((sym.flags() & PUBLIC) == 0) { 2616 return true; 2617 } 2618 sym = sym.owner; 2619 } 2620 return false; 2621 } 2622 2623 /** Report a conflict between a user symbol and a synthetic symbol. 2624 */ 2625 private void syntheticError(DiagnosticPosition pos, Symbol sym) { 2626 if (!sym.type.isErroneous()) { 2627 if (warnOnSyntheticConflicts) { 2628 log.warning(pos, "synthetic.name.conflict", sym, sym.location()); 2629 } 2630 else { 2631 log.error(pos, "synthetic.name.conflict", sym, sym.location()); 2632 } 2633 } 2634 } 2635 2636 /** Check that class c does not implement directly or indirectly 2637 * the same parameterized interface with two different argument lists. 2638 * @param pos Position to be used for error reporting. 2639 * @param type The type whose interfaces are checked. 2640 */ 2641 void checkClassBounds(DiagnosticPosition pos, Type type) { 2642 checkClassBounds(pos, new HashMap<TypeSymbol,Type>(), type); 2643 } 2644//where 2645 /** Enter all interfaces of type `type' into the hash table `seensofar' 2646 * with their class symbol as key and their type as value. Make 2647 * sure no class is entered with two different types. 2648 */ 2649 void checkClassBounds(DiagnosticPosition pos, 2650 Map<TypeSymbol,Type> seensofar, 2651 Type type) { 2652 if (type.isErroneous()) return; 2653 for (List<Type> l = types.interfaces(type); l.nonEmpty(); l = l.tail) { 2654 Type it = l.head; 2655 Type oldit = seensofar.put(it.tsym, it); 2656 if (oldit != null) { 2657 List<Type> oldparams = oldit.allparams(); 2658 List<Type> newparams = it.allparams(); 2659 if (!types.containsTypeEquivalent(oldparams, newparams)) 2660 log.error(pos, "cant.inherit.diff.arg", 2661 it.tsym, Type.toString(oldparams), 2662 Type.toString(newparams)); 2663 } 2664 checkClassBounds(pos, seensofar, it); 2665 } 2666 Type st = types.supertype(type); 2667 if (st != Type.noType) checkClassBounds(pos, seensofar, st); 2668 } 2669 2670 /** Enter interface into into set. 2671 * If it existed already, issue a "repeated interface" error. 2672 */ 2673 void checkNotRepeated(DiagnosticPosition pos, Type it, Set<Type> its) { 2674 if (its.contains(it)) 2675 log.error(pos, "repeated.interface"); 2676 else { 2677 its.add(it); 2678 } 2679 } 2680 2681/* ************************************************************************* 2682 * Check annotations 2683 **************************************************************************/ 2684 2685 /** 2686 * Recursively validate annotations values 2687 */ 2688 void validateAnnotationTree(JCTree tree) { 2689 class AnnotationValidator extends TreeScanner { 2690 @Override 2691 public void visitAnnotation(JCAnnotation tree) { 2692 if (!tree.type.isErroneous()) { 2693 super.visitAnnotation(tree); 2694 validateAnnotation(tree); 2695 } 2696 } 2697 } 2698 tree.accept(new AnnotationValidator()); 2699 } 2700 2701 /** 2702 * {@literal 2703 * Annotation types are restricted to primitives, String, an 2704 * enum, an annotation, Class, Class<?>, Class<? extends 2705 * Anything>, arrays of the preceding. 2706 * } 2707 */ 2708 void validateAnnotationType(JCTree restype) { 2709 // restype may be null if an error occurred, so don't bother validating it 2710 if (restype != null) { 2711 validateAnnotationType(restype.pos(), restype.type); 2712 } 2713 } 2714 2715 void validateAnnotationType(DiagnosticPosition pos, Type type) { 2716 if (type.isPrimitive()) return; 2717 if (types.isSameType(type, syms.stringType)) return; 2718 if ((type.tsym.flags() & Flags.ENUM) != 0) return; 2719 if ((type.tsym.flags() & Flags.ANNOTATION) != 0) return; 2720 if (types.cvarLowerBound(type).tsym == syms.classType.tsym) return; 2721 if (types.isArray(type) && !types.isArray(types.elemtype(type))) { 2722 validateAnnotationType(pos, types.elemtype(type)); 2723 return; 2724 } 2725 log.error(pos, "invalid.annotation.member.type"); 2726 } 2727 2728 /** 2729 * "It is also a compile-time error if any method declared in an 2730 * annotation type has a signature that is override-equivalent to 2731 * that of any public or protected method declared in class Object 2732 * or in the interface annotation.Annotation." 2733 * 2734 * @jls 9.6 Annotation Types 2735 */ 2736 void validateAnnotationMethod(DiagnosticPosition pos, MethodSymbol m) { 2737 for (Type sup = syms.annotationType; sup.hasTag(CLASS); sup = types.supertype(sup)) { 2738 Scope s = sup.tsym.members(); 2739 for (Symbol sym : s.getSymbolsByName(m.name)) { 2740 if (sym.kind == MTH && 2741 (sym.flags() & (PUBLIC | PROTECTED)) != 0 && 2742 types.overrideEquivalent(m.type, sym.type)) 2743 log.error(pos, "intf.annotation.member.clash", sym, sup); 2744 } 2745 } 2746 } 2747 2748 /** Check the annotations of a symbol. 2749 */ 2750 public void validateAnnotations(List<JCAnnotation> annotations, Symbol s) { 2751 for (JCAnnotation a : annotations) 2752 validateAnnotation(a, s); 2753 } 2754 2755 /** Check the type annotations. 2756 */ 2757 public void validateTypeAnnotations(List<JCAnnotation> annotations, boolean isTypeParameter) { 2758 for (JCAnnotation a : annotations) 2759 validateTypeAnnotation(a, isTypeParameter); 2760 } 2761 2762 /** Check an annotation of a symbol. 2763 */ 2764 private void validateAnnotation(JCAnnotation a, Symbol s) { 2765 validateAnnotationTree(a); 2766 2767 if (!annotationApplicable(a, s)) 2768 log.error(a.pos(), "annotation.type.not.applicable"); 2769 2770 if (a.annotationType.type.tsym == syms.functionalInterfaceType.tsym) { 2771 if (s.kind != TYP) { 2772 log.error(a.pos(), "bad.functional.intf.anno"); 2773 } else if (!s.isInterface() || (s.flags() & ANNOTATION) != 0) { 2774 log.error(a.pos(), "bad.functional.intf.anno.1", diags.fragment("not.a.functional.intf", s)); 2775 } 2776 } 2777 } 2778 2779 public void validateTypeAnnotation(JCAnnotation a, boolean isTypeParameter) { 2780 Assert.checkNonNull(a.type); 2781 validateAnnotationTree(a); 2782 2783 if (a.hasTag(TYPE_ANNOTATION) && 2784 !a.annotationType.type.isErroneous() && 2785 !isTypeAnnotation(a, isTypeParameter)) { 2786 log.error(a.pos(), Errors.AnnotationTypeNotApplicableToType(a.type)); 2787 } 2788 } 2789 2790 /** 2791 * Validate the proposed container 'repeatable' on the 2792 * annotation type symbol 's'. Report errors at position 2793 * 'pos'. 2794 * 2795 * @param s The (annotation)type declaration annotated with a @Repeatable 2796 * @param repeatable the @Repeatable on 's' 2797 * @param pos where to report errors 2798 */ 2799 public void validateRepeatable(TypeSymbol s, Attribute.Compound repeatable, DiagnosticPosition pos) { 2800 Assert.check(types.isSameType(repeatable.type, syms.repeatableType)); 2801 2802 Type t = null; 2803 List<Pair<MethodSymbol,Attribute>> l = repeatable.values; 2804 if (!l.isEmpty()) { 2805 Assert.check(l.head.fst.name == names.value); 2806 t = ((Attribute.Class)l.head.snd).getValue(); 2807 } 2808 2809 if (t == null) { 2810 // errors should already have been reported during Annotate 2811 return; 2812 } 2813 2814 validateValue(t.tsym, s, pos); 2815 validateRetention(t.tsym, s, pos); 2816 validateDocumented(t.tsym, s, pos); 2817 validateInherited(t.tsym, s, pos); 2818 validateTarget(t.tsym, s, pos); 2819 validateDefault(t.tsym, pos); 2820 } 2821 2822 private void validateValue(TypeSymbol container, TypeSymbol contained, DiagnosticPosition pos) { 2823 Symbol sym = container.members().findFirst(names.value); 2824 if (sym != null && sym.kind == MTH) { 2825 MethodSymbol m = (MethodSymbol) sym; 2826 Type ret = m.getReturnType(); 2827 if (!(ret.hasTag(ARRAY) && types.isSameType(((ArrayType)ret).elemtype, contained.type))) { 2828 log.error(pos, "invalid.repeatable.annotation.value.return", 2829 container, ret, types.makeArrayType(contained.type)); 2830 } 2831 } else { 2832 log.error(pos, "invalid.repeatable.annotation.no.value", container); 2833 } 2834 } 2835 2836 private void validateRetention(TypeSymbol container, TypeSymbol contained, DiagnosticPosition pos) { 2837 Attribute.RetentionPolicy containerRetention = types.getRetention(container); 2838 Attribute.RetentionPolicy containedRetention = types.getRetention(contained); 2839 2840 boolean error = false; 2841 switch (containedRetention) { 2842 case RUNTIME: 2843 if (containerRetention != Attribute.RetentionPolicy.RUNTIME) { 2844 error = true; 2845 } 2846 break; 2847 case CLASS: 2848 if (containerRetention == Attribute.RetentionPolicy.SOURCE) { 2849 error = true; 2850 } 2851 } 2852 if (error ) { 2853 log.error(pos, "invalid.repeatable.annotation.retention", 2854 container, containerRetention, 2855 contained, containedRetention); 2856 } 2857 } 2858 2859 private void validateDocumented(Symbol container, Symbol contained, DiagnosticPosition pos) { 2860 if (contained.attribute(syms.documentedType.tsym) != null) { 2861 if (container.attribute(syms.documentedType.tsym) == null) { 2862 log.error(pos, "invalid.repeatable.annotation.not.documented", container, contained); 2863 } 2864 } 2865 } 2866 2867 private void validateInherited(Symbol container, Symbol contained, DiagnosticPosition pos) { 2868 if (contained.attribute(syms.inheritedType.tsym) != null) { 2869 if (container.attribute(syms.inheritedType.tsym) == null) { 2870 log.error(pos, "invalid.repeatable.annotation.not.inherited", container, contained); 2871 } 2872 } 2873 } 2874 2875 private void validateTarget(TypeSymbol container, TypeSymbol contained, DiagnosticPosition pos) { 2876 // The set of targets the container is applicable to must be a subset 2877 // (with respect to annotation target semantics) of the set of targets 2878 // the contained is applicable to. The target sets may be implicit or 2879 // explicit. 2880 2881 Set<Name> containerTargets; 2882 Attribute.Array containerTarget = getAttributeTargetAttribute(container); 2883 if (containerTarget == null) { 2884 containerTargets = getDefaultTargetSet(); 2885 } else { 2886 containerTargets = new HashSet<>(); 2887 for (Attribute app : containerTarget.values) { 2888 if (!(app instanceof Attribute.Enum)) { 2889 continue; // recovery 2890 } 2891 Attribute.Enum e = (Attribute.Enum)app; 2892 containerTargets.add(e.value.name); 2893 } 2894 } 2895 2896 Set<Name> containedTargets; 2897 Attribute.Array containedTarget = getAttributeTargetAttribute(contained); 2898 if (containedTarget == null) { 2899 containedTargets = getDefaultTargetSet(); 2900 } else { 2901 containedTargets = new HashSet<>(); 2902 for (Attribute app : containedTarget.values) { 2903 if (!(app instanceof Attribute.Enum)) { 2904 continue; // recovery 2905 } 2906 Attribute.Enum e = (Attribute.Enum)app; 2907 containedTargets.add(e.value.name); 2908 } 2909 } 2910 2911 if (!isTargetSubsetOf(containerTargets, containedTargets)) { 2912 log.error(pos, "invalid.repeatable.annotation.incompatible.target", container, contained); 2913 } 2914 } 2915 2916 /* get a set of names for the default target */ 2917 private Set<Name> getDefaultTargetSet() { 2918 if (defaultTargets == null) { 2919 Set<Name> targets = new HashSet<>(); 2920 targets.add(names.ANNOTATION_TYPE); 2921 targets.add(names.CONSTRUCTOR); 2922 targets.add(names.FIELD); 2923 targets.add(names.LOCAL_VARIABLE); 2924 targets.add(names.METHOD); 2925 targets.add(names.PACKAGE); 2926 targets.add(names.PARAMETER); 2927 targets.add(names.TYPE); 2928 2929 defaultTargets = java.util.Collections.unmodifiableSet(targets); 2930 } 2931 2932 return defaultTargets; 2933 } 2934 private Set<Name> defaultTargets; 2935 2936 2937 /** Checks that s is a subset of t, with respect to ElementType 2938 * semantics, specifically {ANNOTATION_TYPE} is a subset of {TYPE}, 2939 * and {TYPE_USE} covers the set {ANNOTATION_TYPE, TYPE, TYPE_USE, 2940 * TYPE_PARAMETER}. 2941 */ 2942 private boolean isTargetSubsetOf(Set<Name> s, Set<Name> t) { 2943 // Check that all elements in s are present in t 2944 for (Name n2 : s) { 2945 boolean currentElementOk = false; 2946 for (Name n1 : t) { 2947 if (n1 == n2) { 2948 currentElementOk = true; 2949 break; 2950 } else if (n1 == names.TYPE && n2 == names.ANNOTATION_TYPE) { 2951 currentElementOk = true; 2952 break; 2953 } else if (n1 == names.TYPE_USE && 2954 (n2 == names.TYPE || 2955 n2 == names.ANNOTATION_TYPE || 2956 n2 == names.TYPE_PARAMETER)) { 2957 currentElementOk = true; 2958 break; 2959 } 2960 } 2961 if (!currentElementOk) 2962 return false; 2963 } 2964 return true; 2965 } 2966 2967 private void validateDefault(Symbol container, DiagnosticPosition pos) { 2968 // validate that all other elements of containing type has defaults 2969 Scope scope = container.members(); 2970 for(Symbol elm : scope.getSymbols()) { 2971 if (elm.name != names.value && 2972 elm.kind == MTH && 2973 ((MethodSymbol)elm).defaultValue == null) { 2974 log.error(pos, 2975 "invalid.repeatable.annotation.elem.nondefault", 2976 container, 2977 elm); 2978 } 2979 } 2980 } 2981 2982 /** Is s a method symbol that overrides a method in a superclass? */ 2983 boolean isOverrider(Symbol s) { 2984 if (s.kind != MTH || s.isStatic()) 2985 return false; 2986 MethodSymbol m = (MethodSymbol)s; 2987 TypeSymbol owner = (TypeSymbol)m.owner; 2988 for (Type sup : types.closure(owner.type)) { 2989 if (sup == owner.type) 2990 continue; // skip "this" 2991 Scope scope = sup.tsym.members(); 2992 for (Symbol sym : scope.getSymbolsByName(m.name)) { 2993 if (!sym.isStatic() && m.overrides(sym, owner, types, true)) 2994 return true; 2995 } 2996 } 2997 return false; 2998 } 2999 3000 /** Is the annotation applicable to types? */ 3001 protected boolean isTypeAnnotation(JCAnnotation a, boolean isTypeParameter) { 3002 List<Attribute> targets = typeAnnotations.annotationTargets(a.attribute); 3003 return (targets == null) ? 3004 false : 3005 targets.stream() 3006 .anyMatch(attr -> isTypeAnnotation(attr, isTypeParameter)); 3007 } 3008 //where 3009 boolean isTypeAnnotation(Attribute a, boolean isTypeParameter) { 3010 Attribute.Enum e = (Attribute.Enum)a; 3011 return (e.value.name == names.TYPE_USE || 3012 (isTypeParameter && e.value.name == names.TYPE_PARAMETER)); 3013 } 3014 3015 /** Is the annotation applicable to the symbol? */ 3016 boolean annotationApplicable(JCAnnotation a, Symbol s) { 3017 Attribute.Array arr = getAttributeTargetAttribute(a.annotationType.type.tsym); 3018 Name[] targets; 3019 3020 if (arr == null) { 3021 targets = defaultTargetMetaInfo(a, s); 3022 } else { 3023 // TODO: can we optimize this? 3024 targets = new Name[arr.values.length]; 3025 for (int i=0; i<arr.values.length; ++i) { 3026 Attribute app = arr.values[i]; 3027 if (!(app instanceof Attribute.Enum)) { 3028 return true; // recovery 3029 } 3030 Attribute.Enum e = (Attribute.Enum) app; 3031 targets[i] = e.value.name; 3032 } 3033 } 3034 for (Name target : targets) { 3035 if (target == names.TYPE) { 3036 if (s.kind == TYP) 3037 return true; 3038 } else if (target == names.FIELD) { 3039 if (s.kind == VAR && s.owner.kind != MTH) 3040 return true; 3041 } else if (target == names.METHOD) { 3042 if (s.kind == MTH && !s.isConstructor()) 3043 return true; 3044 } else if (target == names.PARAMETER) { 3045 if (s.kind == VAR && s.owner.kind == MTH && 3046 (s.flags() & PARAMETER) != 0) { 3047 return true; 3048 } 3049 } else if (target == names.CONSTRUCTOR) { 3050 if (s.kind == MTH && s.isConstructor()) 3051 return true; 3052 } else if (target == names.LOCAL_VARIABLE) { 3053 if (s.kind == VAR && s.owner.kind == MTH && 3054 (s.flags() & PARAMETER) == 0) { 3055 return true; 3056 } 3057 } else if (target == names.ANNOTATION_TYPE) { 3058 if (s.kind == TYP && (s.flags() & ANNOTATION) != 0) { 3059 return true; 3060 } 3061 } else if (target == names.PACKAGE) { 3062 if (s.kind == PCK) 3063 return true; 3064 } else if (target == names.TYPE_USE) { 3065 if (s.kind == TYP || s.kind == VAR || 3066 (s.kind == MTH && !s.isConstructor() && 3067 !s.type.getReturnType().hasTag(VOID)) || 3068 (s.kind == MTH && s.isConstructor())) { 3069 return true; 3070 } 3071 } else if (target == names.TYPE_PARAMETER) { 3072 if (s.kind == TYP && s.type.hasTag(TYPEVAR)) 3073 return true; 3074 } else 3075 return true; // Unknown ElementType. This should be an error at declaration site, 3076 // assume applicable. 3077 } 3078 return false; 3079 } 3080 3081 3082 Attribute.Array getAttributeTargetAttribute(TypeSymbol s) { 3083 Attribute.Compound atTarget = s.getAnnotationTypeMetadata().getTarget(); 3084 if (atTarget == null) return null; // ok, is applicable 3085 Attribute atValue = atTarget.member(names.value); 3086 if (!(atValue instanceof Attribute.Array)) return null; // error recovery 3087 return (Attribute.Array) atValue; 3088 } 3089 3090 private final Name[] dfltTargetMeta; 3091 private Name[] defaultTargetMetaInfo(JCAnnotation a, Symbol s) { 3092 return dfltTargetMeta; 3093 } 3094 3095 /** Check an annotation value. 3096 * 3097 * @param a The annotation tree to check 3098 * @return true if this annotation tree is valid, otherwise false 3099 */ 3100 public boolean validateAnnotationDeferErrors(JCAnnotation a) { 3101 boolean res = false; 3102 final Log.DiagnosticHandler diagHandler = new Log.DiscardDiagnosticHandler(log); 3103 try { 3104 res = validateAnnotation(a); 3105 } finally { 3106 log.popDiagnosticHandler(diagHandler); 3107 } 3108 return res; 3109 } 3110 3111 private boolean validateAnnotation(JCAnnotation a) { 3112 boolean isValid = true; 3113 AnnotationTypeMetadata metadata = a.annotationType.type.tsym.getAnnotationTypeMetadata(); 3114 3115 // collect an inventory of the annotation elements 3116 Set<MethodSymbol> elements = metadata.getAnnotationElements(); 3117 3118 // remove the ones that are assigned values 3119 for (JCTree arg : a.args) { 3120 if (!arg.hasTag(ASSIGN)) continue; // recovery 3121 JCAssign assign = (JCAssign)arg; 3122 Symbol m = TreeInfo.symbol(assign.lhs); 3123 if (m == null || m.type.isErroneous()) continue; 3124 if (!elements.remove(m)) { 3125 isValid = false; 3126 log.error(assign.lhs.pos(), "duplicate.annotation.member.value", 3127 m.name, a.type); 3128 } 3129 } 3130 3131 // all the remaining ones better have default values 3132 List<Name> missingDefaults = List.nil(); 3133 Set<MethodSymbol> membersWithDefault = metadata.getAnnotationElementsWithDefault(); 3134 for (MethodSymbol m : elements) { 3135 if (m.type.isErroneous()) 3136 continue; 3137 3138 if (!membersWithDefault.contains(m)) 3139 missingDefaults = missingDefaults.append(m.name); 3140 } 3141 missingDefaults = missingDefaults.reverse(); 3142 if (missingDefaults.nonEmpty()) { 3143 isValid = false; 3144 String key = (missingDefaults.size() > 1) 3145 ? "annotation.missing.default.value.1" 3146 : "annotation.missing.default.value"; 3147 log.error(a.pos(), key, a.type, missingDefaults); 3148 } 3149 3150 return isValid && validateTargetAnnotationValue(a); 3151 } 3152 3153 /* Validate the special java.lang.annotation.Target annotation */ 3154 boolean validateTargetAnnotationValue(JCAnnotation a) { 3155 // special case: java.lang.annotation.Target must not have 3156 // repeated values in its value member 3157 if (a.annotationType.type.tsym != syms.annotationTargetType.tsym || 3158 a.args.tail == null) 3159 return true; 3160 3161 boolean isValid = true; 3162 if (!a.args.head.hasTag(ASSIGN)) return false; // error recovery 3163 JCAssign assign = (JCAssign) a.args.head; 3164 Symbol m = TreeInfo.symbol(assign.lhs); 3165 if (m.name != names.value) return false; 3166 JCTree rhs = assign.rhs; 3167 if (!rhs.hasTag(NEWARRAY)) return false; 3168 JCNewArray na = (JCNewArray) rhs; 3169 Set<Symbol> targets = new HashSet<>(); 3170 for (JCTree elem : na.elems) { 3171 if (!targets.add(TreeInfo.symbol(elem))) { 3172 isValid = false; 3173 log.error(elem.pos(), "repeated.annotation.target"); 3174 } 3175 } 3176 return isValid; 3177 } 3178 3179 void checkDeprecatedAnnotation(DiagnosticPosition pos, Symbol s) { 3180 if (lint.isEnabled(LintCategory.DEP_ANN) && 3181 (s.flags() & DEPRECATED) != 0 && 3182 !syms.deprecatedType.isErroneous() && 3183 s.attribute(syms.deprecatedType.tsym) == null) { 3184 log.warning(LintCategory.DEP_ANN, 3185 pos, "missing.deprecated.annotation"); 3186 } 3187 } 3188 3189 void checkDeprecated(final DiagnosticPosition pos, final Symbol other, final Symbol s) { 3190 if ((s.flags() & DEPRECATED) != 0 && 3191 (other.flags() & DEPRECATED) == 0 && 3192 s.outermostClass() != other.outermostClass()) { 3193 deferredLintHandler.report(new DeferredLintHandler.LintLogger() { 3194 @Override 3195 public void report() { 3196 warnDeprecated(pos, s); 3197 } 3198 }); 3199 } 3200 } 3201 3202 void checkSunAPI(final DiagnosticPosition pos, final Symbol s) { 3203 if ((s.flags() & PROPRIETARY) != 0) { 3204 deferredLintHandler.report(new DeferredLintHandler.LintLogger() { 3205 public void report() { 3206 if (enableSunApiLintControl) 3207 warnSunApi(pos, "sun.proprietary", s); 3208 else 3209 log.mandatoryWarning(pos, "sun.proprietary", s); 3210 } 3211 }); 3212 } 3213 } 3214 3215 void checkProfile(final DiagnosticPosition pos, final Symbol s) { 3216 if (profile != Profile.DEFAULT && (s.flags() & NOT_IN_PROFILE) != 0) { 3217 log.error(pos, "not.in.profile", s, profile); 3218 } 3219 } 3220 3221/* ************************************************************************* 3222 * Check for recursive annotation elements. 3223 **************************************************************************/ 3224 3225 /** Check for cycles in the graph of annotation elements. 3226 */ 3227 void checkNonCyclicElements(JCClassDecl tree) { 3228 if ((tree.sym.flags_field & ANNOTATION) == 0) return; 3229 Assert.check((tree.sym.flags_field & LOCKED) == 0); 3230 try { 3231 tree.sym.flags_field |= LOCKED; 3232 for (JCTree def : tree.defs) { 3233 if (!def.hasTag(METHODDEF)) continue; 3234 JCMethodDecl meth = (JCMethodDecl)def; 3235 checkAnnotationResType(meth.pos(), meth.restype.type); 3236 } 3237 } finally { 3238 tree.sym.flags_field &= ~LOCKED; 3239 tree.sym.flags_field |= ACYCLIC_ANN; 3240 } 3241 } 3242 3243 void checkNonCyclicElementsInternal(DiagnosticPosition pos, TypeSymbol tsym) { 3244 if ((tsym.flags_field & ACYCLIC_ANN) != 0) 3245 return; 3246 if ((tsym.flags_field & LOCKED) != 0) { 3247 log.error(pos, "cyclic.annotation.element"); 3248 return; 3249 } 3250 try { 3251 tsym.flags_field |= LOCKED; 3252 for (Symbol s : tsym.members().getSymbols(NON_RECURSIVE)) { 3253 if (s.kind != MTH) 3254 continue; 3255 checkAnnotationResType(pos, ((MethodSymbol)s).type.getReturnType()); 3256 } 3257 } finally { 3258 tsym.flags_field &= ~LOCKED; 3259 tsym.flags_field |= ACYCLIC_ANN; 3260 } 3261 } 3262 3263 void checkAnnotationResType(DiagnosticPosition pos, Type type) { 3264 switch (type.getTag()) { 3265 case CLASS: 3266 if ((type.tsym.flags() & ANNOTATION) != 0) 3267 checkNonCyclicElementsInternal(pos, type.tsym); 3268 break; 3269 case ARRAY: 3270 checkAnnotationResType(pos, types.elemtype(type)); 3271 break; 3272 default: 3273 break; // int etc 3274 } 3275 } 3276 3277/* ************************************************************************* 3278 * Check for cycles in the constructor call graph. 3279 **************************************************************************/ 3280 3281 /** Check for cycles in the graph of constructors calling other 3282 * constructors. 3283 */ 3284 void checkCyclicConstructors(JCClassDecl tree) { 3285 Map<Symbol,Symbol> callMap = new HashMap<>(); 3286 3287 // enter each constructor this-call into the map 3288 for (List<JCTree> l = tree.defs; l.nonEmpty(); l = l.tail) { 3289 JCMethodInvocation app = TreeInfo.firstConstructorCall(l.head); 3290 if (app == null) continue; 3291 JCMethodDecl meth = (JCMethodDecl) l.head; 3292 if (TreeInfo.name(app.meth) == names._this) { 3293 callMap.put(meth.sym, TreeInfo.symbol(app.meth)); 3294 } else { 3295 meth.sym.flags_field |= ACYCLIC; 3296 } 3297 } 3298 3299 // Check for cycles in the map 3300 Symbol[] ctors = new Symbol[0]; 3301 ctors = callMap.keySet().toArray(ctors); 3302 for (Symbol caller : ctors) { 3303 checkCyclicConstructor(tree, caller, callMap); 3304 } 3305 } 3306 3307 /** Look in the map to see if the given constructor is part of a 3308 * call cycle. 3309 */ 3310 private void checkCyclicConstructor(JCClassDecl tree, Symbol ctor, 3311 Map<Symbol,Symbol> callMap) { 3312 if (ctor != null && (ctor.flags_field & ACYCLIC) == 0) { 3313 if ((ctor.flags_field & LOCKED) != 0) { 3314 log.error(TreeInfo.diagnosticPositionFor(ctor, tree), 3315 "recursive.ctor.invocation"); 3316 } else { 3317 ctor.flags_field |= LOCKED; 3318 checkCyclicConstructor(tree, callMap.remove(ctor), callMap); 3319 ctor.flags_field &= ~LOCKED; 3320 } 3321 ctor.flags_field |= ACYCLIC; 3322 } 3323 } 3324 3325/* ************************************************************************* 3326 * Miscellaneous 3327 **************************************************************************/ 3328 3329 /** 3330 * Check for division by integer constant zero 3331 * @param pos Position for error reporting. 3332 * @param operator The operator for the expression 3333 * @param operand The right hand operand for the expression 3334 */ 3335 void checkDivZero(final DiagnosticPosition pos, Symbol operator, Type operand) { 3336 if (operand.constValue() != null 3337 && operand.getTag().isSubRangeOf(LONG) 3338 && ((Number) (operand.constValue())).longValue() == 0) { 3339 int opc = ((OperatorSymbol)operator).opcode; 3340 if (opc == ByteCodes.idiv || opc == ByteCodes.imod 3341 || opc == ByteCodes.ldiv || opc == ByteCodes.lmod) { 3342 deferredLintHandler.report(new DeferredLintHandler.LintLogger() { 3343 @Override 3344 public void report() { 3345 warnDivZero(pos); 3346 } 3347 }); 3348 } 3349 } 3350 } 3351 3352 /** 3353 * Check for empty statements after if 3354 */ 3355 void checkEmptyIf(JCIf tree) { 3356 if (tree.thenpart.hasTag(SKIP) && tree.elsepart == null && 3357 lint.isEnabled(LintCategory.EMPTY)) 3358 log.warning(LintCategory.EMPTY, tree.thenpart.pos(), "empty.if"); 3359 } 3360 3361 /** Check that symbol is unique in given scope. 3362 * @param pos Position for error reporting. 3363 * @param sym The symbol. 3364 * @param s The scope. 3365 */ 3366 boolean checkUnique(DiagnosticPosition pos, Symbol sym, Scope s) { 3367 if (sym.type.isErroneous()) 3368 return true; 3369 if (sym.owner.name == names.any) return false; 3370 for (Symbol byName : s.getSymbolsByName(sym.name, NON_RECURSIVE)) { 3371 if (sym != byName && 3372 (byName.flags() & CLASH) == 0 && 3373 sym.kind == byName.kind && 3374 sym.name != names.error && 3375 (sym.kind != MTH || 3376 types.hasSameArgs(sym.type, byName.type) || 3377 types.hasSameArgs(types.erasure(sym.type), types.erasure(byName.type)))) { 3378 if ((sym.flags() & VARARGS) != (byName.flags() & VARARGS)) { 3379 varargsDuplicateError(pos, sym, byName); 3380 return true; 3381 } else if (sym.kind == MTH && !types.hasSameArgs(sym.type, byName.type, false)) { 3382 duplicateErasureError(pos, sym, byName); 3383 sym.flags_field |= CLASH; 3384 return true; 3385 } else { 3386 duplicateError(pos, byName); 3387 return false; 3388 } 3389 } 3390 } 3391 return true; 3392 } 3393 3394 /** Report duplicate declaration error. 3395 */ 3396 void duplicateErasureError(DiagnosticPosition pos, Symbol sym1, Symbol sym2) { 3397 if (!sym1.type.isErroneous() && !sym2.type.isErroneous()) { 3398 log.error(pos, "name.clash.same.erasure", sym1, sym2); 3399 } 3400 } 3401 3402 /**Check that types imported through the ordinary imports don't clash with types imported 3403 * by other (static or ordinary) imports. Note that two static imports may import two clashing 3404 * types without an error on the imports. 3405 * @param toplevel The toplevel tree for which the test should be performed. 3406 */ 3407 void checkImportsUnique(JCCompilationUnit toplevel) { 3408 WriteableScope ordinallyImportedSoFar = WriteableScope.create(toplevel.packge); 3409 WriteableScope staticallyImportedSoFar = WriteableScope.create(toplevel.packge); 3410 WriteableScope topLevelScope = toplevel.toplevelScope; 3411 3412 for (JCTree def : toplevel.defs) { 3413 if (!def.hasTag(IMPORT)) 3414 continue; 3415 3416 JCImport imp = (JCImport) def; 3417 3418 if (imp.importScope == null) 3419 continue; 3420 3421 for (Symbol sym : imp.importScope.getSymbols(sym -> sym.kind == TYP)) { 3422 if (imp.isStatic()) { 3423 checkUniqueImport(imp.pos(), ordinallyImportedSoFar, staticallyImportedSoFar, topLevelScope, sym, true); 3424 staticallyImportedSoFar.enter(sym); 3425 } else { 3426 checkUniqueImport(imp.pos(), ordinallyImportedSoFar, staticallyImportedSoFar, topLevelScope, sym, false); 3427 ordinallyImportedSoFar.enter(sym); 3428 } 3429 } 3430 3431 imp.importScope = null; 3432 } 3433 } 3434 3435 /** Check that single-type import is not already imported or top-level defined, 3436 * but make an exception for two single-type imports which denote the same type. 3437 * @param pos Position for error reporting. 3438 * @param ordinallyImportedSoFar A Scope containing types imported so far through 3439 * ordinary imports. 3440 * @param staticallyImportedSoFar A Scope containing types imported so far through 3441 * static imports. 3442 * @param topLevelScope The current file's top-level Scope 3443 * @param sym The symbol. 3444 * @param staticImport Whether or not this was a static import 3445 */ 3446 private boolean checkUniqueImport(DiagnosticPosition pos, Scope ordinallyImportedSoFar, 3447 Scope staticallyImportedSoFar, Scope topLevelScope, 3448 Symbol sym, boolean staticImport) { 3449 Filter<Symbol> duplicates = candidate -> candidate != sym && !candidate.type.isErroneous(); 3450 Symbol clashing = ordinallyImportedSoFar.findFirst(sym.name, duplicates); 3451 if (clashing == null && !staticImport) { 3452 clashing = staticallyImportedSoFar.findFirst(sym.name, duplicates); 3453 } 3454 if (clashing != null) { 3455 if (staticImport) 3456 log.error(pos, "already.defined.static.single.import", clashing); 3457 else 3458 log.error(pos, "already.defined.single.import", clashing); 3459 return false; 3460 } 3461 clashing = topLevelScope.findFirst(sym.name, duplicates); 3462 if (clashing != null) { 3463 log.error(pos, "already.defined.this.unit", clashing); 3464 return false; 3465 } 3466 return true; 3467 } 3468 3469 /** Check that a qualified name is in canonical form (for import decls). 3470 */ 3471 public void checkCanonical(JCTree tree) { 3472 if (!isCanonical(tree)) 3473 log.error(tree.pos(), "import.requires.canonical", 3474 TreeInfo.symbol(tree)); 3475 } 3476 // where 3477 private boolean isCanonical(JCTree tree) { 3478 while (tree.hasTag(SELECT)) { 3479 JCFieldAccess s = (JCFieldAccess) tree; 3480 if (s.sym.owner != TreeInfo.symbol(s.selected)) 3481 return false; 3482 tree = s.selected; 3483 } 3484 return true; 3485 } 3486 3487 /** Check that an auxiliary class is not accessed from any other file than its own. 3488 */ 3489 void checkForBadAuxiliaryClassAccess(DiagnosticPosition pos, Env<AttrContext> env, ClassSymbol c) { 3490 if (lint.isEnabled(Lint.LintCategory.AUXILIARYCLASS) && 3491 (c.flags() & AUXILIARY) != 0 && 3492 rs.isAccessible(env, c) && 3493 !fileManager.isSameFile(c.sourcefile, env.toplevel.sourcefile)) 3494 { 3495 log.warning(pos, "auxiliary.class.accessed.from.outside.of.its.source.file", 3496 c, c.sourcefile); 3497 } 3498 } 3499 3500 private class ConversionWarner extends Warner { 3501 final String uncheckedKey; 3502 final Type found; 3503 final Type expected; 3504 public ConversionWarner(DiagnosticPosition pos, String uncheckedKey, Type found, Type expected) { 3505 super(pos); 3506 this.uncheckedKey = uncheckedKey; 3507 this.found = found; 3508 this.expected = expected; 3509 } 3510 3511 @Override 3512 public void warn(LintCategory lint) { 3513 boolean warned = this.warned; 3514 super.warn(lint); 3515 if (warned) return; // suppress redundant diagnostics 3516 switch (lint) { 3517 case UNCHECKED: 3518 Check.this.warnUnchecked(pos(), "prob.found.req", diags.fragment(uncheckedKey), found, expected); 3519 break; 3520 case VARARGS: 3521 if (method != null && 3522 method.attribute(syms.trustMeType.tsym) != null && 3523 isTrustMeAllowedOnMethod(method) && 3524 !types.isReifiable(method.type.getParameterTypes().last())) { 3525 Check.this.warnUnsafeVararg(pos(), "varargs.unsafe.use.varargs.param", method.params.last()); 3526 } 3527 break; 3528 default: 3529 throw new AssertionError("Unexpected lint: " + lint); 3530 } 3531 } 3532 } 3533 3534 public Warner castWarner(DiagnosticPosition pos, Type found, Type expected) { 3535 return new ConversionWarner(pos, "unchecked.cast.to.type", found, expected); 3536 } 3537 3538 public Warner convertWarner(DiagnosticPosition pos, Type found, Type expected) { 3539 return new ConversionWarner(pos, "unchecked.assign", found, expected); 3540 } 3541 3542 public void checkFunctionalInterface(JCClassDecl tree, ClassSymbol cs) { 3543 Compound functionalType = cs.attribute(syms.functionalInterfaceType.tsym); 3544 3545 if (functionalType != null) { 3546 try { 3547 types.findDescriptorSymbol((TypeSymbol)cs); 3548 } catch (Types.FunctionDescriptorLookupError ex) { 3549 DiagnosticPosition pos = tree.pos(); 3550 for (JCAnnotation a : tree.getModifiers().annotations) { 3551 if (a.annotationType.type.tsym == syms.functionalInterfaceType.tsym) { 3552 pos = a.pos(); 3553 break; 3554 } 3555 } 3556 log.error(pos, "bad.functional.intf.anno.1", ex.getDiagnostic()); 3557 } 3558 } 3559 } 3560 3561 public void checkImportsResolvable(final JCCompilationUnit toplevel) { 3562 for (final JCImport imp : toplevel.getImports()) { 3563 if (!imp.staticImport || !imp.qualid.hasTag(SELECT)) 3564 continue; 3565 final JCFieldAccess select = (JCFieldAccess) imp.qualid; 3566 final Symbol origin; 3567 if (select.name == names.asterisk || (origin = TreeInfo.symbol(select.selected)) == null || origin.kind != TYP) 3568 continue; 3569 3570 TypeSymbol site = (TypeSymbol) TreeInfo.symbol(select.selected); 3571 if (!checkTypeContainsImportableElement(site, site, toplevel.packge, select.name, new HashSet<Symbol>())) { 3572 log.error(imp.pos(), "cant.resolve.location", 3573 KindName.STATIC, 3574 select.name, List.<Type>nil(), List.<Type>nil(), 3575 Kinds.typeKindName(TreeInfo.symbol(select.selected).type), 3576 TreeInfo.symbol(select.selected).type); 3577 } 3578 } 3579 } 3580 3581 private boolean checkTypeContainsImportableElement(TypeSymbol tsym, TypeSymbol origin, PackageSymbol packge, Name name, Set<Symbol> processed) { 3582 if (tsym == null || !processed.add(tsym)) 3583 return false; 3584 3585 // also search through inherited names 3586 if (checkTypeContainsImportableElement(types.supertype(tsym.type).tsym, origin, packge, name, processed)) 3587 return true; 3588 3589 for (Type t : types.interfaces(tsym.type)) 3590 if (checkTypeContainsImportableElement(t.tsym, origin, packge, name, processed)) 3591 return true; 3592 3593 for (Symbol sym : tsym.members().getSymbolsByName(name)) { 3594 if (sym.isStatic() && 3595 importAccessible(sym, packge) && 3596 sym.isMemberOf(origin, types)) { 3597 return true; 3598 } 3599 } 3600 3601 return false; 3602 } 3603 3604 // is the sym accessible everywhere in packge? 3605 public boolean importAccessible(Symbol sym, PackageSymbol packge) { 3606 try { 3607 int flags = (int)(sym.flags() & AccessFlags); 3608 switch (flags) { 3609 default: 3610 case PUBLIC: 3611 return true; 3612 case PRIVATE: 3613 return false; 3614 case 0: 3615 case PROTECTED: 3616 return sym.packge() == packge; 3617 } 3618 } catch (ClassFinder.BadClassFile err) { 3619 throw err; 3620 } catch (CompletionFailure ex) { 3621 return false; 3622 } 3623 } 3624 3625} 3626