1 /* 2 * Copyright (c) 1999, 2022, Oracle and/or its affiliates. All rights reserved. 3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. 4 * 5 * This code is free software; you can redistribute it and/or modify it 6 * under the terms of the GNU General Public License version 2 only, as 7 * published by the Free Software Foundation. Oracle designates this 8 * particular file as subject to the "Classpath" exception as provided 9 * by Oracle in the LICENSE file that accompanied this code. 10 * 11 * This code is distributed in the hope that it will be useful, but WITHOUT 12 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or 13 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License 14 * version 2 for more details (a copy is included in the LICENSE file that 15 * accompanied this code). 16 * 17 * You should have received a copy of the GNU General Public License version 18 * 2 along with this work; if not, write to the Free Software Foundation, 19 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. 20 * 21 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA 22 * or visit www.oracle.com if you need additional information or have any 23 * questions. 24 */ 25 26 package com.sun.tools.javac.comp; 27 28 import java.util.*; 29 import java.util.function.BiConsumer; 30 import java.util.function.Predicate; 31 import java.util.function.Supplier; 32 33 import javax.lang.model.element.ElementKind; 34 import javax.lang.model.element.NestingKind; 35 import javax.tools.JavaFileManager; 36 37 import com.sun.source.tree.CaseTree; 38 import com.sun.tools.javac.code.*; 39 import com.sun.tools.javac.code.Attribute.Compound; 40 import com.sun.tools.javac.code.Directive.ExportsDirective; 41 import com.sun.tools.javac.code.Directive.RequiresDirective; 42 import com.sun.tools.javac.code.Source.Feature; 43 import com.sun.tools.javac.comp.Annotate.AnnotationTypeMetadata; 44 import com.sun.tools.javac.jvm.*; 45 import com.sun.tools.javac.resources.CompilerProperties.Errors; 46 import com.sun.tools.javac.resources.CompilerProperties.Fragments; 47 import com.sun.tools.javac.resources.CompilerProperties.Warnings; 48 import com.sun.tools.javac.tree.*; 49 import com.sun.tools.javac.util.*; 50 import com.sun.tools.javac.util.JCDiagnostic.DiagnosticFlag; 51 import com.sun.tools.javac.util.JCDiagnostic.DiagnosticPosition; 52 import com.sun.tools.javac.util.JCDiagnostic.Error; 53 import com.sun.tools.javac.util.JCDiagnostic.Fragment; 54 import com.sun.tools.javac.util.JCDiagnostic.Warning; 55 import com.sun.tools.javac.util.List; 56 57 import com.sun.tools.javac.code.Lint; 58 import com.sun.tools.javac.code.Lint.LintCategory; 59 import com.sun.tools.javac.code.Scope.WriteableScope; 60 import com.sun.tools.javac.code.Type.*; 61 import com.sun.tools.javac.code.Symbol.*; 62 import com.sun.tools.javac.comp.DeferredAttr.DeferredAttrContext; 63 import com.sun.tools.javac.tree.JCTree.*; 64 65 import static com.sun.tools.javac.code.Flags.*; 66 import static com.sun.tools.javac.code.Flags.ANNOTATION; 67 import static com.sun.tools.javac.code.Flags.SYNCHRONIZED; 68 import static com.sun.tools.javac.code.Kinds.*; 69 import static com.sun.tools.javac.code.Kinds.Kind.*; 70 import static com.sun.tools.javac.code.Scope.LookupKind.NON_RECURSIVE; 71 import static com.sun.tools.javac.code.TypeTag.*; 72 import static com.sun.tools.javac.code.TypeTag.WILDCARD; 73 74 import static com.sun.tools.javac.tree.JCTree.Tag.*; 75 import javax.lang.model.element.Element; 76 import javax.lang.model.element.ExecutableElement; 77 import javax.lang.model.element.TypeElement; 78 import javax.lang.model.type.DeclaredType; 79 import javax.lang.model.type.TypeMirror; 80 import javax.lang.model.util.ElementFilter; 81 import javax.lang.model.util.ElementKindVisitor14; 82 83 /** Type checking helper class for the attribution phase. 84 * 85 * <p><b>This is NOT part of any supported API. 86 * If you write code that depends on this, you do so at your own risk. 87 * This code and its internal interfaces are subject to change or 88 * deletion without notice.</b> 89 */ 90 public class Check { 91 protected static final Context.Key<Check> checkKey = new Context.Key<>(); 92 93 private final Names names; 94 private final Log log; 95 private final Resolve rs; 96 private final Symtab syms; 97 private final Enter enter; 98 private final DeferredAttr deferredAttr; 99 private final Infer infer; 100 private final Types types; 101 private final TypeAnnotations typeAnnotations; 102 private final JCDiagnostic.Factory diags; 103 private final JavaFileManager fileManager; 104 private final Source source; 105 private final Target target; 106 private final Profile profile; 107 private final Preview preview; 108 private final boolean warnOnAnyAccessToMembers; 109 110 // The set of lint options currently in effect. It is initialized 111 // from the context, and then is set/reset as needed by Attr as it 112 // visits all the various parts of the trees during attribution. 113 private Lint lint; 114 115 // The method being analyzed in Attr - it is set/reset as needed by 116 // Attr as it visits new method declarations. 117 private MethodSymbol method; 118 119 public static Check instance(Context context) { 120 Check instance = context.get(checkKey); 121 if (instance == null) 122 instance = new Check(context); 123 return instance; 124 } 125 126 protected Check(Context context) { 127 context.put(checkKey, this); 128 129 names = Names.instance(context); 130 log = Log.instance(context); 131 rs = Resolve.instance(context); 132 syms = Symtab.instance(context); 133 enter = Enter.instance(context); 134 deferredAttr = DeferredAttr.instance(context); 135 infer = Infer.instance(context); 136 types = Types.instance(context); 137 typeAnnotations = TypeAnnotations.instance(context); 138 diags = JCDiagnostic.Factory.instance(context); 139 Options options = Options.instance(context); 140 lint = Lint.instance(context); 141 fileManager = context.get(JavaFileManager.class); 142 143 source = Source.instance(context); 144 target = Target.instance(context); 145 warnOnAnyAccessToMembers = options.isSet("warnOnAccessToMembers"); 146 147 Target target = Target.instance(context); 148 syntheticNameChar = target.syntheticNameChar(); 149 150 profile = Profile.instance(context); 151 preview = Preview.instance(context); 152 153 boolean verboseDeprecated = lint.isEnabled(LintCategory.DEPRECATION); 154 boolean verboseRemoval = lint.isEnabled(LintCategory.REMOVAL); 155 boolean verboseUnchecked = lint.isEnabled(LintCategory.UNCHECKED); 156 boolean enforceMandatoryWarnings = true; 157 158 deprecationHandler = new MandatoryWarningHandler(log, null, verboseDeprecated, 159 enforceMandatoryWarnings, "deprecated", LintCategory.DEPRECATION); 160 removalHandler = new MandatoryWarningHandler(log, null, verboseRemoval, 161 enforceMandatoryWarnings, "removal", LintCategory.REMOVAL); 162 uncheckedHandler = new MandatoryWarningHandler(log, null, verboseUnchecked, 163 enforceMandatoryWarnings, "unchecked", LintCategory.UNCHECKED); 164 sunApiHandler = new MandatoryWarningHandler(log, null, false, 165 enforceMandatoryWarnings, "sunapi", null); 166 167 deferredLintHandler = DeferredLintHandler.instance(context); 168 169 allowModules = Feature.MODULES.allowedInSource(source); 170 allowRecords = Feature.RECORDS.allowedInSource(source); 171 allowSealed = Feature.SEALED_CLASSES.allowedInSource(source); 172 allowPrimitiveClasses = Feature.PRIMITIVE_CLASSES.allowedInSource(source) && options.isSet("enablePrimitiveClasses"); 173 } 174 175 /** Character for synthetic names 176 */ 177 char syntheticNameChar; 178 179 /** A table mapping flat names of all compiled classes for each module in this run 180 * to their symbols; maintained from outside. 181 */ 182 private Map<Pair<ModuleSymbol, Name>,ClassSymbol> compiled = new HashMap<>(); 183 184 /** A handler for messages about deprecated usage. 185 */ 186 private MandatoryWarningHandler deprecationHandler; 187 188 /** A handler for messages about deprecated-for-removal usage. 189 */ 190 private MandatoryWarningHandler removalHandler; 191 192 /** A handler for messages about unchecked or unsafe usage. 193 */ 194 private MandatoryWarningHandler uncheckedHandler; 195 196 /** A handler for messages about using proprietary API. 197 */ 198 private MandatoryWarningHandler sunApiHandler; 199 200 /** A handler for deferred lint warnings. 201 */ 202 private DeferredLintHandler deferredLintHandler; 203 204 /** Are modules allowed 205 */ 206 private final boolean allowModules; 207 208 /** Are records allowed 209 */ 210 private final boolean allowRecords; 211 212 /** Are sealed classes allowed 213 */ 214 private final boolean allowSealed; 215 216 /** Are primitive classes allowed 217 */ 218 private final boolean allowPrimitiveClasses; 219 220 /* ************************************************************************* 221 * Errors and Warnings 222 **************************************************************************/ 223 224 Lint setLint(Lint newLint) { 225 Lint prev = lint; 226 lint = newLint; 227 return prev; 228 } 229 230 MethodSymbol setMethod(MethodSymbol newMethod) { 231 MethodSymbol prev = method; 232 method = newMethod; 233 return prev; 234 } 235 236 /** Warn about deprecated symbol. 237 * @param pos Position to be used for error reporting. 238 * @param sym The deprecated symbol. 239 */ 240 void warnDeprecated(DiagnosticPosition pos, Symbol sym) { 241 if (sym.isDeprecatedForRemoval()) { 242 if (!lint.isSuppressed(LintCategory.REMOVAL)) { 243 if (sym.kind == MDL) { 244 removalHandler.report(pos, Warnings.HasBeenDeprecatedForRemovalModule(sym)); 245 } else { 246 removalHandler.report(pos, Warnings.HasBeenDeprecatedForRemoval(sym, sym.location())); 247 } 248 } 249 } else if (!lint.isSuppressed(LintCategory.DEPRECATION)) { 250 if (sym.kind == MDL) { 251 deprecationHandler.report(pos, Warnings.HasBeenDeprecatedModule(sym)); 252 } else { 253 deprecationHandler.report(pos, Warnings.HasBeenDeprecated(sym, sym.location())); 254 } 255 } 256 } 257 258 /** Log a preview warning. 259 * @param pos Position to be used for error reporting. 260 * @param msg A Warning describing the problem. 261 */ 262 public void warnPreviewAPI(DiagnosticPosition pos, Warning warnKey) { 263 if (!lint.isSuppressed(LintCategory.PREVIEW)) 264 preview.reportPreviewWarning(pos, warnKey); 265 } 266 267 /** Log a preview warning. 268 * @param pos Position to be used for error reporting. 269 * @param msg A Warning describing the problem. 270 */ 271 public void warnDeclaredUsingPreview(DiagnosticPosition pos, Symbol sym) { 272 if (!lint.isSuppressed(LintCategory.PREVIEW)) 273 preview.reportPreviewWarning(pos, Warnings.DeclaredUsingPreview(kindName(sym), sym)); 274 } 275 276 /** Warn about unchecked operation. 277 * @param pos Position to be used for error reporting. 278 * @param msg A string describing the problem. 279 */ 280 public void warnUnchecked(DiagnosticPosition pos, Warning warnKey) { 281 if (!lint.isSuppressed(LintCategory.UNCHECKED)) 282 uncheckedHandler.report(pos, warnKey); 283 } 284 285 /** Warn about unsafe vararg method decl. 286 * @param pos Position to be used for error reporting. 287 */ 288 void warnUnsafeVararg(DiagnosticPosition pos, Warning warnKey) { 289 if (lint.isEnabled(LintCategory.VARARGS)) 290 log.warning(LintCategory.VARARGS, pos, warnKey); 291 } 292 293 public void warnStatic(DiagnosticPosition pos, Warning warnKey) { 294 if (lint.isEnabled(LintCategory.STATIC)) 295 log.warning(LintCategory.STATIC, pos, warnKey); 296 } 297 298 /** Warn about division by integer constant zero. 299 * @param pos Position to be used for error reporting. 300 */ 301 void warnDivZero(DiagnosticPosition pos) { 302 if (lint.isEnabled(LintCategory.DIVZERO)) 303 log.warning(LintCategory.DIVZERO, pos, Warnings.DivZero); 304 } 305 306 /** 307 * Report any deferred diagnostics. 308 */ 309 public void reportDeferredDiagnostics() { 310 deprecationHandler.reportDeferredDiagnostic(); 311 removalHandler.reportDeferredDiagnostic(); 312 uncheckedHandler.reportDeferredDiagnostic(); 313 sunApiHandler.reportDeferredDiagnostic(); 314 } 315 316 317 /** Report a failure to complete a class. 318 * @param pos Position to be used for error reporting. 319 * @param ex The failure to report. 320 */ 321 public Type completionError(DiagnosticPosition pos, CompletionFailure ex) { 322 log.error(JCDiagnostic.DiagnosticFlag.NON_DEFERRABLE, pos, Errors.CantAccess(ex.sym, ex.getDetailValue())); 323 return syms.errType; 324 } 325 326 /** Report an error that wrong type tag was found. 327 * @param pos Position to be used for error reporting. 328 * @param required An internationalized string describing the type tag 329 * required. 330 * @param found The type that was found. 331 */ 332 Type typeTagError(DiagnosticPosition pos, JCDiagnostic required, Object found) { 333 // this error used to be raised by the parser, 334 // but has been delayed to this point: 335 if (found instanceof Type type && type.hasTag(VOID)) { 336 log.error(pos, Errors.IllegalStartOfType); 337 return syms.errType; 338 } 339 log.error(pos, Errors.TypeFoundReq(found, required)); 340 return types.createErrorType(found instanceof Type type ? type : syms.errType); 341 } 342 343 /** Report an error that symbol cannot be referenced before super 344 * has been called. 345 * @param pos Position to be used for error reporting. 346 * @param sym The referenced symbol. 347 */ 348 void earlyRefError(DiagnosticPosition pos, Symbol sym) { 349 log.error(pos, Errors.CantRefBeforeCtorCalled(sym)); 350 } 351 352 /** Report duplicate declaration error. 353 */ 354 void duplicateError(DiagnosticPosition pos, Symbol sym) { 355 if (!sym.type.isErroneous()) { 356 Symbol location = sym.location(); 357 if (location.kind == MTH && 358 ((MethodSymbol)location).isStaticOrInstanceInit()) { 359 log.error(pos, 360 Errors.AlreadyDefinedInClinit(kindName(sym), 361 sym, 362 kindName(sym.location()), 363 kindName(sym.location().enclClass()), 364 sym.location().enclClass())); 365 } else { 366 /* dont error if this is a duplicated parameter of a generated canonical constructor 367 * as we should have issued an error for the duplicated fields 368 */ 369 if (location.kind != MTH || 370 ((sym.owner.flags_field & GENERATEDCONSTR) == 0) || 371 ((sym.owner.flags_field & RECORD) == 0)) { 372 log.error(pos, 373 Errors.AlreadyDefined(kindName(sym), 374 sym, 375 kindName(sym.location()), 376 sym.location())); 377 } 378 } 379 } 380 } 381 382 /** Report array/varargs duplicate declaration 383 */ 384 void varargsDuplicateError(DiagnosticPosition pos, Symbol sym1, Symbol sym2) { 385 if (!sym1.type.isErroneous() && !sym2.type.isErroneous()) { 386 log.error(pos, Errors.ArrayAndVarargs(sym1, sym2, sym2.location())); 387 } 388 } 389 390 /* ************************************************************************ 391 * duplicate declaration checking 392 *************************************************************************/ 393 394 /** Check that variable does not hide variable with same name in 395 * immediately enclosing local scope. 396 * @param pos Position for error reporting. 397 * @param v The symbol. 398 * @param s The scope. 399 */ 400 void checkTransparentVar(DiagnosticPosition pos, VarSymbol v, Scope s) { 401 for (Symbol sym : s.getSymbolsByName(v.name)) { 402 if (sym.owner != v.owner) break; 403 if (sym.kind == VAR && 404 sym.owner.kind.matches(KindSelector.VAL_MTH) && 405 v.name != names.error) { 406 duplicateError(pos, sym); 407 return; 408 } 409 } 410 } 411 412 /** Check that a class or interface does not hide a class or 413 * interface with same name in immediately enclosing local scope. 414 * @param pos Position for error reporting. 415 * @param c The symbol. 416 * @param s The scope. 417 */ 418 void checkTransparentClass(DiagnosticPosition pos, ClassSymbol c, Scope s) { 419 for (Symbol sym : s.getSymbolsByName(c.name)) { 420 if (sym.owner != c.owner) break; 421 if (sym.kind == TYP && !sym.type.hasTag(TYPEVAR) && 422 sym.owner.kind.matches(KindSelector.VAL_MTH) && 423 c.name != names.error) { 424 duplicateError(pos, sym); 425 return; 426 } 427 } 428 } 429 430 /** Check that class does not have the same name as one of 431 * its enclosing classes, or as a class defined in its enclosing scope. 432 * return true if class is unique in its enclosing scope. 433 * @param pos Position for error reporting. 434 * @param name The class name. 435 * @param s The enclosing scope. 436 */ 437 boolean checkUniqueClassName(DiagnosticPosition pos, Name name, Scope s) { 438 for (Symbol sym : s.getSymbolsByName(name, NON_RECURSIVE)) { 439 if (sym.kind == TYP && sym.name != names.error) { 440 duplicateError(pos, sym); 441 return false; 442 } 443 } 444 for (Symbol sym = s.owner; sym != null; sym = sym.owner) { 445 if (sym.kind == TYP && sym.name == name && sym.name != names.error) { 446 duplicateError(pos, sym); 447 return true; 448 } 449 } 450 return true; 451 } 452 453 /* ************************************************************************* 454 * Class name generation 455 **************************************************************************/ 456 457 458 private Map<Pair<Name, Name>, Integer> localClassNameIndexes = new HashMap<>(); 459 460 /** Return name of local class. 461 * This is of the form {@code <enclClass> $ n <classname> } 462 * where 463 * enclClass is the flat name of the enclosing class, 464 * classname is the simple name of the local class 465 */ 466 public Name localClassName(ClassSymbol c) { 467 Name enclFlatname = c.owner.enclClass().flatname; 468 String enclFlatnameStr = enclFlatname.toString(); 469 Pair<Name, Name> key = new Pair<>(enclFlatname, c.name); 470 Integer index = localClassNameIndexes.get(key); 471 for (int i = (index == null) ? 1 : index; ; i++) { 472 Name flatname = names.fromString(enclFlatnameStr 473 + syntheticNameChar + i + c.name); 474 if (getCompiled(c.packge().modle, flatname) == null) { 475 localClassNameIndexes.put(key, i + 1); 476 return flatname; 477 } 478 } 479 } 480 481 public void clearLocalClassNameIndexes(ClassSymbol c) { 482 if (c.owner != null && c.owner.kind != NIL) { 483 localClassNameIndexes.remove(new Pair<>( 484 c.owner.enclClass().flatname, c.name)); 485 } 486 } 487 488 public void newRound() { 489 compiled.clear(); 490 localClassNameIndexes.clear(); 491 } 492 493 public void clear() { 494 deprecationHandler.clear(); 495 removalHandler.clear(); 496 uncheckedHandler.clear(); 497 sunApiHandler.clear(); 498 } 499 500 public void putCompiled(ClassSymbol csym) { 501 compiled.put(Pair.of(csym.packge().modle, csym.flatname), csym); 502 } 503 504 public ClassSymbol getCompiled(ClassSymbol csym) { 505 return compiled.get(Pair.of(csym.packge().modle, csym.flatname)); 506 } 507 508 public ClassSymbol getCompiled(ModuleSymbol msym, Name flatname) { 509 return compiled.get(Pair.of(msym, flatname)); 510 } 511 512 public void removeCompiled(ClassSymbol csym) { 513 compiled.remove(Pair.of(csym.packge().modle, csym.flatname)); 514 } 515 516 /* ************************************************************************* 517 * Type Checking 518 **************************************************************************/ 519 520 /** 521 * A check context is an object that can be used to perform compatibility 522 * checks - depending on the check context, meaning of 'compatibility' might 523 * vary significantly. 524 */ 525 public interface CheckContext { 526 /** 527 * Is type 'found' compatible with type 'req' in given context 528 */ 529 boolean compatible(Type found, Type req, Warner warn); 530 /** 531 * Report a check error 532 */ 533 void report(DiagnosticPosition pos, JCDiagnostic details); 534 /** 535 * Obtain a warner for this check context 536 */ 537 public Warner checkWarner(DiagnosticPosition pos, Type found, Type req); 538 539 public InferenceContext inferenceContext(); 540 541 public DeferredAttr.DeferredAttrContext deferredAttrContext(); 542 } 543 544 /** 545 * This class represent a check context that is nested within another check 546 * context - useful to check sub-expressions. The default behavior simply 547 * redirects all method calls to the enclosing check context leveraging 548 * the forwarding pattern. 549 */ 550 static class NestedCheckContext implements CheckContext { 551 CheckContext enclosingContext; 552 553 NestedCheckContext(CheckContext enclosingContext) { 554 this.enclosingContext = enclosingContext; 555 } 556 557 public boolean compatible(Type found, Type req, Warner warn) { 558 return enclosingContext.compatible(found, req, warn); 559 } 560 561 public void report(DiagnosticPosition pos, JCDiagnostic details) { 562 enclosingContext.report(pos, details); 563 } 564 565 public Warner checkWarner(DiagnosticPosition pos, Type found, Type req) { 566 return enclosingContext.checkWarner(pos, found, req); 567 } 568 569 public InferenceContext inferenceContext() { 570 return enclosingContext.inferenceContext(); 571 } 572 573 public DeferredAttrContext deferredAttrContext() { 574 return enclosingContext.deferredAttrContext(); 575 } 576 } 577 578 /** 579 * Check context to be used when evaluating assignment/return statements 580 */ 581 CheckContext basicHandler = new CheckContext() { 582 public void report(DiagnosticPosition pos, JCDiagnostic details) { 583 log.error(pos, Errors.ProbFoundReq(details)); 584 } 585 public boolean compatible(Type found, Type req, Warner warn) { 586 return types.isAssignable(found, req, warn); 587 } 588 589 public Warner checkWarner(DiagnosticPosition pos, Type found, Type req) { 590 return convertWarner(pos, found, req); 591 } 592 593 public InferenceContext inferenceContext() { 594 return infer.emptyContext; 595 } 596 597 public DeferredAttrContext deferredAttrContext() { 598 return deferredAttr.emptyDeferredAttrContext; 599 } 600 601 @Override 602 public String toString() { 603 return "CheckContext: basicHandler"; 604 } 605 }; 606 607 /** Check that a given type is assignable to a given proto-type. 608 * If it is, return the type, otherwise return errType. 609 * @param pos Position to be used for error reporting. 610 * @param found The type that was found. 611 * @param req The type that was required. 612 */ 613 public Type checkType(DiagnosticPosition pos, Type found, Type req) { 614 return checkType(pos, found, req, basicHandler); 615 } 616 617 Type checkType(final DiagnosticPosition pos, final Type found, final Type req, final CheckContext checkContext) { 618 final InferenceContext inferenceContext = checkContext.inferenceContext(); 619 if (inferenceContext.free(req) || inferenceContext.free(found)) { 620 inferenceContext.addFreeTypeListener(List.of(req, found), 621 solvedContext -> checkType(pos, solvedContext.asInstType(found), solvedContext.asInstType(req), checkContext)); 622 } else { 623 if (allowPrimitiveClasses && found.hasTag(CLASS)) { 624 if (inferenceContext != infer.emptyContext) 625 checkParameterizationByPrimitiveClass(pos, found); 626 } 627 } 628 if (req.hasTag(ERROR)) 629 return req; 630 if (req.hasTag(NONE)) 631 return found; 632 if (checkContext.compatible(found, req, checkContext.checkWarner(pos, found, req))) { 633 return found; 634 } else { 635 if (found.isNumeric() && req.isNumeric()) { 636 checkContext.report(pos, diags.fragment(Fragments.PossibleLossOfPrecision(found, req))); 637 return types.createErrorType(found); 638 } 639 checkContext.report(pos, diags.fragment(Fragments.InconvertibleTypes(found, req))); 640 return types.createErrorType(found); 641 } 642 } 643 644 /** Check that a given type can be cast to a given target type. 645 * Return the result of the cast. 646 * @param pos Position to be used for error reporting. 647 * @param found The type that is being cast. 648 * @param req The target type of the cast. 649 */ 650 Type checkCastable(DiagnosticPosition pos, Type found, Type req) { 651 return checkCastable(pos, found, req, basicHandler); 652 } 653 Type checkCastable(DiagnosticPosition pos, Type found, Type req, CheckContext checkContext) { 654 if (types.isCastable(found, req, castWarner(pos, found, req))) { 655 return req; 656 } else { 657 checkContext.report(pos, diags.fragment(Fragments.InconvertibleTypes(found, req))); 658 return types.createErrorType(found); 659 } 660 } 661 662 /** Check for redundant casts (i.e. where source type is a subtype of target type) 663 * The problem should only be reported for non-292 cast 664 */ 665 public void checkRedundantCast(Env<AttrContext> env, final JCTypeCast tree) { 666 if (!tree.type.isErroneous() 667 && types.isSameType(tree.expr.type, tree.clazz.type) 668 && !(ignoreAnnotatedCasts && TreeInfo.containsTypeAnnotation(tree.clazz)) 669 && !is292targetTypeCast(tree)) { 670 deferredLintHandler.report(() -> { 671 if (lint.isEnabled(LintCategory.CAST)) 672 log.warning(LintCategory.CAST, 673 tree.pos(), Warnings.RedundantCast(tree.clazz.type)); 674 }); 675 } 676 } 677 //where 678 private boolean is292targetTypeCast(JCTypeCast tree) { 679 boolean is292targetTypeCast = false; 680 JCExpression expr = TreeInfo.skipParens(tree.expr); 681 if (expr.hasTag(APPLY)) { 682 JCMethodInvocation apply = (JCMethodInvocation)expr; 683 Symbol sym = TreeInfo.symbol(apply.meth); 684 is292targetTypeCast = sym != null && 685 sym.kind == MTH && 686 (sym.flags() & HYPOTHETICAL) != 0; 687 } 688 return is292targetTypeCast; 689 } 690 691 private static final boolean ignoreAnnotatedCasts = true; 692 693 /** Check that a type is within some bounds. 694 * 695 * Used in TypeApply to verify that, e.g., X in {@code V<X>} is a valid 696 * type argument. 697 * @param a The type that should be bounded by bs. 698 * @param bound The bound. 699 */ 700 private boolean checkExtends(Type a, Type bound) { 701 if (a.isUnbound()) { 702 return true; 703 } else if (!a.hasTag(WILDCARD)) { 704 a = types.cvarUpperBound(a); 705 return types.isSubtype(a, bound); 706 } else if (a.isExtendsBound()) { 707 return types.isCastable(bound, types.wildUpperBound(a), types.noWarnings); 708 } else if (a.isSuperBound()) { 709 return !types.notSoftSubtype(types.wildLowerBound(a), bound); 710 } 711 return true; 712 } 713 714 /** Check that type is different from 'void'. 715 * @param pos Position to be used for error reporting. 716 * @param t The type to be checked. 717 */ 718 Type checkNonVoid(DiagnosticPosition pos, Type t) { 719 if (t.hasTag(VOID)) { 720 log.error(pos, Errors.VoidNotAllowedHere); 721 return types.createErrorType(t); 722 } else { 723 return t; 724 } 725 } 726 727 Type checkClassOrArrayType(DiagnosticPosition pos, Type t) { 728 if (!t.hasTag(CLASS) && !t.hasTag(ARRAY) && !t.hasTag(ERROR)) { 729 return typeTagError(pos, 730 diags.fragment(Fragments.TypeReqClassArray), 731 asTypeParam(t)); 732 } else { 733 return t; 734 } 735 } 736 737 /** Check that type is a class or interface type. 738 * @param pos Position to be used for error reporting. 739 * @param t The type to be checked. 740 */ 741 Type checkClassType(DiagnosticPosition pos, Type t) { 742 if (!t.hasTag(CLASS) && !t.hasTag(ERROR)) { 743 return typeTagError(pos, 744 diags.fragment(Fragments.TypeReqClass), 745 asTypeParam(t)); 746 } else { 747 return t; 748 } 749 } 750 //where 751 private Object asTypeParam(Type t) { 752 return (t.hasTag(TYPEVAR)) 753 ? diags.fragment(Fragments.TypeParameter(t)) 754 : t; 755 } 756 757 void checkConstraintsOfValueClass(DiagnosticPosition pos, ClassSymbol c) { 758 for (Type st : types.closure(c.type)) { 759 if (st == null || st.tsym == null || st.tsym.kind == ERR) 760 continue; 761 if (st.tsym == syms.objectType.tsym || st.tsym == syms.recordType.tsym || st.isInterface()) 762 continue; 763 if (!st.tsym.isAbstract()) { 764 if (c != st.tsym) { 765 log.error(pos, Errors.ConcreteSupertypeForValueClass(c, st)); 766 } 767 continue; 768 } 769 // dealing with an abstract value or value super class below. 770 Fragment fragment = c.isAbstract() && c.isValueClass() && c == st.tsym ? Fragments.AbstractValueClass(c) : Fragments.SuperclassOfValueClass(c, st); 771 if ((st.tsym.flags() & HASINITBLOCK) != 0) { 772 log.error(pos, Errors.AbstractValueClassDeclaresInitBlock(fragment)); 773 } 774 Type encl = st.getEnclosingType(); 775 if (encl != null && encl.hasTag(CLASS)) { 776 log.error(pos, Errors.AbstractValueClassCannotBeInner(fragment)); 777 } 778 for (Symbol s : st.tsym.members().getSymbols(NON_RECURSIVE)) { 779 switch (s.kind) { 780 case VAR: 781 if ((s.flags() & STATIC) == 0) { 782 log.error(pos, Errors.InstanceFieldNotAllowed(s, fragment)); 783 } 784 break; 785 case MTH: 786 if ((s.flags() & (SYNCHRONIZED | STATIC)) == SYNCHRONIZED) { 787 log.error(pos, Errors.SuperClassMethodCannotBeSynchronized(s, c, st)); 788 } else if (s.isInitOrVNew()) { 789 MethodSymbol m = (MethodSymbol)s; 790 if (m.getParameters().size() > 0) { 791 log.error(pos, Errors.AbstractValueClassConstructorCannotTakeArguments(m, fragment)); 792 } else if (m.getTypeParameters().size() > 0) { 793 log.error(pos, Errors.AbstractValueClassConstructorCannotBeGeneric(m, fragment)); 794 } else if (m.type.getThrownTypes().size() > 0) { 795 log.error(pos, Errors.AbstractValueClassConstructorCannotThrow(m, fragment)); 796 } else if (protection(m.flags()) > protection(m.owner.flags())) { 797 log.error(pos, Errors.AbstractValueClassConstructorHasWeakerAccess(m, fragment)); 798 } else if ((m.flags() & EMPTYNOARGCONSTR) == 0) { 799 log.error(pos, Errors.AbstractValueClassNoArgConstructorMustBeEmpty(m, fragment)); 800 } 801 } 802 break; 803 } 804 } 805 } 806 } 807 808 /** Check that type is a valid qualifier for a constructor reference expression 809 */ 810 Type checkConstructorRefType(JCExpression expr, Type t) { 811 t = checkClassOrArrayType(expr, t); 812 if (t.hasTag(CLASS)) { 813 if ((t.tsym.flags() & (ABSTRACT | INTERFACE)) != 0) { 814 log.error(expr, Errors.AbstractCantBeInstantiated(t.tsym)); 815 t = types.createErrorType(t); 816 } else if ((t.tsym.flags() & ENUM) != 0) { 817 log.error(expr, Errors.EnumCantBeInstantiated); 818 t = types.createErrorType(t); 819 } else { 820 // Projection types may not be mentioned in constructor references 821 if (expr.hasTag(SELECT)) { 822 JCFieldAccess fieldAccess = (JCFieldAccess) expr; 823 if (allowPrimitiveClasses && fieldAccess.selected.type.isPrimitiveClass() && 824 (fieldAccess.name == names.ref || fieldAccess.name == names.val)) { 825 log.error(expr, Errors.ProjectionCantBeInstantiated); 826 t = types.createErrorType(t); 827 } 828 } 829 t = checkClassType(expr, t, true); 830 } 831 } else if (t.hasTag(ARRAY)) { 832 if (!types.isReifiable(((ArrayType)t).elemtype)) { 833 log.error(expr, Errors.GenericArrayCreation); 834 t = types.createErrorType(t); 835 } 836 } 837 return t; 838 } 839 840 /** Check that type is a class or interface type. 841 * @param pos Position to be used for error reporting. 842 * @param t The type to be checked. 843 * @param noBounds True if type bounds are illegal here. 844 */ 845 Type checkClassType(DiagnosticPosition pos, Type t, boolean noBounds) { 846 t = checkClassType(pos, t); 847 if (noBounds && t.isParameterized()) { 848 List<Type> args = t.getTypeArguments(); 849 while (args.nonEmpty()) { 850 if (args.head.hasTag(WILDCARD)) 851 return typeTagError(pos, 852 diags.fragment(Fragments.TypeReqExact), 853 args.head); 854 args = args.tail; 855 } 856 } 857 return t; 858 } 859 860 /** Check that type is a reference type, i.e. a class, interface or array type 861 * or a type variable. 862 * @param pos Position to be used for error reporting. 863 * @param t The type to be checked. 864 * @param primitiveClassOK If false, a primitive class does not qualify 865 */ 866 Type checkRefType(DiagnosticPosition pos, Type t, boolean primitiveClassOK) { 867 if (t.isReference() && (!allowPrimitiveClasses || primitiveClassOK || !t.isPrimitiveClass())) 868 return t; 869 else 870 return typeTagError(pos, 871 diags.fragment(Fragments.TypeReqRef), 872 t); 873 } 874 875 /** Check that type is an identity type, i.e. not a primitive/value type 876 * nor its reference projection. When not discernible statically, 877 * give it the benefit of doubt and defer to runtime. 878 * 879 * @param pos Position to be used for error reporting. 880 * @param t The type to be checked. 881 */ 882 void checkIdentityType(DiagnosticPosition pos, Type t) { 883 if (t.hasTag(TYPEVAR)) { 884 t = types.skipTypeVars(t, false); 885 } 886 if (t.isIntersection()) { 887 IntersectionClassType ict = (IntersectionClassType)t; 888 for (Type component : ict.getExplicitComponents()) { 889 checkIdentityType(pos, component); 890 } 891 return; 892 } 893 if (t.isPrimitive() || t.isValueClass() || t.isValueInterface() || t.isReferenceProjection()) 894 typeTagError(pos, diags.fragment(Fragments.TypeReqIdentity), t); 895 } 896 897 /** Check that type is a reference type, i.e. a class, interface or array type 898 * or a type variable. 899 * @param pos Position to be used for error reporting. 900 * @param t The type to be checked. 901 */ 902 Type checkRefType(DiagnosticPosition pos, Type t) { 903 return checkRefType(pos, t, true); 904 } 905 906 /** Check that each type is a reference type, i.e. a class, interface or array type 907 * or a type variable. 908 * @param trees Original trees, used for error reporting. 909 * @param types The types to be checked. 910 */ 911 List<Type> checkRefTypes(List<JCExpression> trees, List<Type> types) { 912 List<JCExpression> tl = trees; 913 for (List<Type> l = types; l.nonEmpty(); l = l.tail) { 914 l.head = checkRefType(tl.head.pos(), l.head, false); 915 tl = tl.tail; 916 } 917 return types; 918 } 919 920 /** Check that type is a null or reference type. 921 * @param pos Position to be used for error reporting. 922 * @param t The type to be checked. 923 */ 924 Type checkNullOrRefType(DiagnosticPosition pos, Type t) { 925 if (t.isReference() || t.hasTag(BOT)) 926 return t; 927 else 928 return typeTagError(pos, 929 diags.fragment(Fragments.TypeReqRef), 930 t); 931 } 932 933 /** Check that flag set does not contain elements of two conflicting sets. s 934 * Return true if it doesn't. 935 * @param pos Position to be used for error reporting. 936 * @param flags The set of flags to be checked. 937 * @param set1 Conflicting flags set #1. 938 * @param set2 Conflicting flags set #2. 939 */ 940 boolean checkDisjoint(DiagnosticPosition pos, long flags, long set1, long set2) { 941 if ((flags & set1) != 0 && (flags & set2) != 0) { 942 log.error(pos, 943 Errors.IllegalCombinationOfModifiers(asFlagSet(TreeInfo.firstFlag(flags & set1)), 944 asFlagSet(TreeInfo.firstFlag(flags & set2)))); 945 return false; 946 } else 947 return true; 948 } 949 950 void checkParameterizationByPrimitiveClass(DiagnosticPosition pos, Type t) { 951 parameterizationByPrimitiveClassChecker.visit(t, pos); 952 } 953 954 /** parameterizationByPrimitiveClassChecker: A type visitor that descends down the given type looking for instances of primitive classes 955 * being used as type arguments and issues error against those usages. 956 */ 957 private final Types.SimpleVisitor<Void, DiagnosticPosition> parameterizationByPrimitiveClassChecker = 958 new Types.SimpleVisitor<Void, DiagnosticPosition>() { 959 960 @Override 961 public Void visitType(Type t, DiagnosticPosition pos) { 962 return null; 963 } 964 965 @Override 966 public Void visitClassType(ClassType t, DiagnosticPosition pos) { 967 for (Type targ : t.allparams()) { 968 if (allowPrimitiveClasses && targ.isPrimitiveClass()) { 969 log.error(pos, Errors.GenericParameterizationWithPrimitiveClass(t)); 970 } 971 visit(targ, pos); 972 } 973 return null; 974 } 975 976 @Override 977 public Void visitTypeVar(TypeVar t, DiagnosticPosition pos) { 978 return null; 979 } 980 981 @Override 982 public Void visitCapturedType(CapturedType t, DiagnosticPosition pos) { 983 return null; 984 } 985 986 @Override 987 public Void visitArrayType(ArrayType t, DiagnosticPosition pos) { 988 return visit(t.elemtype, pos); 989 } 990 991 @Override 992 public Void visitWildcardType(WildcardType t, DiagnosticPosition pos) { 993 return visit(t.type, pos); 994 } 995 }; 996 997 998 999 /** Check that usage of diamond operator is correct (i.e. diamond should not 1000 * be used with non-generic classes or in anonymous class creation expressions) 1001 */ 1002 Type checkDiamond(JCNewClass tree, Type t) { 1003 if (!TreeInfo.isDiamond(tree) || 1004 t.isErroneous()) { 1005 return checkClassType(tree.clazz.pos(), t, true); 1006 } else { 1007 if (tree.def != null && !Feature.DIAMOND_WITH_ANONYMOUS_CLASS_CREATION.allowedInSource(source)) { 1008 log.error(DiagnosticFlag.SOURCE_LEVEL, tree.clazz.pos(), 1009 Errors.CantApplyDiamond1(t, Feature.DIAMOND_WITH_ANONYMOUS_CLASS_CREATION.fragment(source.name))); 1010 } 1011 if (t.tsym.type.getTypeArguments().isEmpty()) { 1012 log.error(tree.clazz.pos(), 1013 Errors.CantApplyDiamond1(t, 1014 Fragments.DiamondNonGeneric(t))); 1015 return types.createErrorType(t); 1016 } else if (tree.typeargs != null && 1017 tree.typeargs.nonEmpty()) { 1018 log.error(tree.clazz.pos(), 1019 Errors.CantApplyDiamond1(t, 1020 Fragments.DiamondAndExplicitParams(t))); 1021 return types.createErrorType(t); 1022 } else { 1023 return t; 1024 } 1025 } 1026 } 1027 1028 /** Check that the type inferred using the diamond operator does not contain 1029 * non-denotable types such as captured types or intersection types. 1030 * @param t the type inferred using the diamond operator 1031 * @return the (possibly empty) list of non-denotable types. 1032 */ 1033 List<Type> checkDiamondDenotable(ClassType t) { 1034 ListBuffer<Type> buf = new ListBuffer<>(); 1035 for (Type arg : t.allparams()) { 1036 if (!checkDenotable(arg)) { 1037 buf.append(arg); 1038 } 1039 } 1040 return buf.toList(); 1041 } 1042 1043 public boolean checkDenotable(Type t) { 1044 return denotableChecker.visit(t, null); 1045 } 1046 // where 1047 1048 /** diamondTypeChecker: A type visitor that descends down the given type looking for non-denotable 1049 * types. The visit methods return false as soon as a non-denotable type is encountered and true 1050 * otherwise. 1051 */ 1052 private static final Types.SimpleVisitor<Boolean, Void> denotableChecker = new Types.SimpleVisitor<Boolean, Void>() { 1053 @Override 1054 public Boolean visitType(Type t, Void s) { 1055 return true; 1056 } 1057 @Override 1058 public Boolean visitClassType(ClassType t, Void s) { 1059 if (t.isUnion() || t.isIntersection()) { 1060 return false; 1061 } 1062 for (Type targ : t.allparams()) { 1063 if (!visit(targ, s)) { 1064 return false; 1065 } 1066 } 1067 return true; 1068 } 1069 1070 @Override 1071 public Boolean visitTypeVar(TypeVar t, Void s) { 1072 /* Any type variable mentioned in the inferred type must have been declared as a type parameter 1073 (i.e cannot have been produced by inference (18.4)) 1074 */ 1075 return (t.tsym.flags() & SYNTHETIC) == 0; 1076 } 1077 1078 @Override 1079 public Boolean visitCapturedType(CapturedType t, Void s) { 1080 /* Any type variable mentioned in the inferred type must have been declared as a type parameter 1081 (i.e cannot have been produced by capture conversion (5.1.10)) 1082 */ 1083 return false; 1084 } 1085 1086 @Override 1087 public Boolean visitArrayType(ArrayType t, Void s) { 1088 return visit(t.elemtype, s); 1089 } 1090 1091 @Override 1092 public Boolean visitWildcardType(WildcardType t, Void s) { 1093 return visit(t.type, s); 1094 } 1095 }; 1096 1097 void checkVarargsMethodDecl(Env<AttrContext> env, JCMethodDecl tree) { 1098 MethodSymbol m = tree.sym; 1099 boolean hasTrustMeAnno = m.attribute(syms.trustMeType.tsym) != null; 1100 Type varargElemType = null; 1101 if (m.isVarArgs()) { 1102 varargElemType = types.elemtype(tree.params.last().type); 1103 } 1104 if (hasTrustMeAnno && !isTrustMeAllowedOnMethod(m)) { 1105 if (varargElemType != null) { 1106 JCDiagnostic msg = Feature.PRIVATE_SAFE_VARARGS.allowedInSource(source) ? 1107 diags.fragment(Fragments.VarargsTrustmeOnVirtualVarargs(m)) : 1108 diags.fragment(Fragments.VarargsTrustmeOnVirtualVarargsFinalOnly(m)); 1109 log.error(tree, 1110 Errors.VarargsInvalidTrustmeAnno(syms.trustMeType.tsym, 1111 msg)); 1112 } else { 1113 log.error(tree, 1114 Errors.VarargsInvalidTrustmeAnno(syms.trustMeType.tsym, 1115 Fragments.VarargsTrustmeOnNonVarargsMeth(m))); 1116 } 1117 } else if (hasTrustMeAnno && varargElemType != null && 1118 types.isReifiable(varargElemType)) { 1119 warnUnsafeVararg(tree, Warnings.VarargsRedundantTrustmeAnno( 1120 syms.trustMeType.tsym, 1121 diags.fragment(Fragments.VarargsTrustmeOnReifiableVarargs(varargElemType)))); 1122 } 1123 else if (!hasTrustMeAnno && varargElemType != null && 1124 !types.isReifiable(varargElemType)) { 1125 warnUnchecked(tree.params.head.pos(), Warnings.UncheckedVarargsNonReifiableType(varargElemType)); 1126 } 1127 } 1128 //where 1129 private boolean isTrustMeAllowedOnMethod(Symbol s) { 1130 return (s.flags() & VARARGS) != 0 && 1131 (s.isInitOrVNew() || 1132 (s.flags() & (STATIC | FINAL | 1133 (Feature.PRIVATE_SAFE_VARARGS.allowedInSource(source) ? PRIVATE : 0) )) != 0); 1134 } 1135 1136 Type checkLocalVarType(DiagnosticPosition pos, Type t, Name name) { 1137 //check that resulting type is not the null type 1138 if (t.hasTag(BOT)) { 1139 log.error(pos, Errors.CantInferLocalVarType(name, Fragments.LocalCantInferNull)); 1140 return types.createErrorType(t); 1141 } else if (t.hasTag(VOID)) { 1142 log.error(pos, Errors.CantInferLocalVarType(name, Fragments.LocalCantInferVoid)); 1143 return types.createErrorType(t); 1144 } 1145 1146 //upward project the initializer type 1147 Type varType = types.upward(t, types.captures(t)).baseType(); 1148 if (allowPrimitiveClasses && varType.hasTag(CLASS)) { 1149 checkParameterizationByPrimitiveClass(pos, varType); 1150 } 1151 return varType; 1152 } 1153 1154 Type checkMethod(final Type mtype, 1155 final Symbol sym, 1156 final Env<AttrContext> env, 1157 final List<JCExpression> argtrees, 1158 final List<Type> argtypes, 1159 final boolean useVarargs, 1160 InferenceContext inferenceContext) { 1161 // System.out.println("call : " + env.tree); 1162 // System.out.println("method : " + owntype); 1163 // System.out.println("actuals: " + argtypes); 1164 if (inferenceContext.free(mtype)) { 1165 inferenceContext.addFreeTypeListener(List.of(mtype), 1166 solvedContext -> checkMethod(solvedContext.asInstType(mtype), sym, env, argtrees, argtypes, useVarargs, solvedContext)); 1167 return mtype; 1168 } 1169 Type owntype = mtype; 1170 List<Type> formals = owntype.getParameterTypes(); 1171 List<Type> nonInferred = sym.type.getParameterTypes(); 1172 if (nonInferred.length() != formals.length()) nonInferred = formals; 1173 Type last = useVarargs ? formals.last() : null; 1174 // TODO - is enum so <init> 1175 if (sym.name == names.init && sym.owner == syms.enumSym) { 1176 formals = formals.tail.tail; 1177 nonInferred = nonInferred.tail.tail; 1178 } 1179 if ((sym.flags() & ANONCONSTR_BASED) != 0) { 1180 formals = formals.tail; 1181 nonInferred = nonInferred.tail; 1182 } 1183 List<JCExpression> args = argtrees; 1184 if (args != null) { 1185 //this is null when type-checking a method reference 1186 while (formals.head != last) { 1187 JCTree arg = args.head; 1188 Warner warn = convertWarner(arg.pos(), arg.type, nonInferred.head); 1189 assertConvertible(arg, arg.type, formals.head, warn); 1190 args = args.tail; 1191 formals = formals.tail; 1192 nonInferred = nonInferred.tail; 1193 } 1194 if (useVarargs) { 1195 Type varArg = types.elemtype(last); 1196 while (args.tail != null) { 1197 JCTree arg = args.head; 1198 Warner warn = convertWarner(arg.pos(), arg.type, varArg); 1199 assertConvertible(arg, arg.type, varArg, warn); 1200 args = args.tail; 1201 } 1202 } else if ((sym.flags() & (VARARGS | SIGNATURE_POLYMORPHIC)) == VARARGS) { 1203 // non-varargs call to varargs method 1204 Type varParam = owntype.getParameterTypes().last(); 1205 Type lastArg = argtypes.last(); 1206 if (types.isSubtypeUnchecked(lastArg, types.elemtype(varParam)) && 1207 !types.isSameType(types.erasure(varParam), types.erasure(lastArg))) 1208 log.warning(argtrees.last().pos(), 1209 Warnings.InexactNonVarargsCall(types.elemtype(varParam),varParam)); 1210 } 1211 } 1212 if (useVarargs) { 1213 Type argtype = owntype.getParameterTypes().last(); 1214 if (!types.isReifiable(argtype) && 1215 (sym.baseSymbol().attribute(syms.trustMeType.tsym) == null || 1216 !isTrustMeAllowedOnMethod(sym))) { 1217 warnUnchecked(env.tree.pos(), Warnings.UncheckedGenericArrayCreation(argtype)); 1218 } 1219 TreeInfo.setVarargsElement(env.tree, types.elemtype(argtype)); 1220 } 1221 return owntype; 1222 } 1223 //where 1224 private void assertConvertible(JCTree tree, Type actual, Type formal, Warner warn) { 1225 if (types.isConvertible(actual, formal, warn)) 1226 return; 1227 1228 if (formal.isCompound() 1229 && types.isSubtype(actual, types.supertype(formal)) 1230 && types.isSubtypeUnchecked(actual, types.interfaces(formal), warn)) 1231 return; 1232 } 1233 1234 /** 1235 * Check that type 't' is a valid instantiation of a generic class 1236 * (see JLS 4.5) 1237 * 1238 * @param t class type to be checked 1239 * @return true if 't' is well-formed 1240 */ 1241 public boolean checkValidGenericType(Type t) { 1242 return firstIncompatibleTypeArg(t) == null; 1243 } 1244 //WHERE 1245 private Type firstIncompatibleTypeArg(Type type) { 1246 List<Type> formals = type.tsym.type.allparams(); 1247 List<Type> actuals = type.allparams(); 1248 List<Type> args = type.getTypeArguments(); 1249 List<Type> forms = type.tsym.type.getTypeArguments(); 1250 ListBuffer<Type> bounds_buf = new ListBuffer<>(); 1251 1252 // For matching pairs of actual argument types `a' and 1253 // formal type parameters with declared bound `b' ... 1254 while (args.nonEmpty() && forms.nonEmpty()) { 1255 // exact type arguments needs to know their 1256 // bounds (for upper and lower bound 1257 // calculations). So we create new bounds where 1258 // type-parameters are replaced with actuals argument types. 1259 bounds_buf.append(types.subst(forms.head.getUpperBound(), formals, actuals)); 1260 args = args.tail; 1261 forms = forms.tail; 1262 } 1263 1264 args = type.getTypeArguments(); 1265 List<Type> tvars_cap = types.substBounds(formals, 1266 formals, 1267 types.capture(type).allparams()); 1268 while (args.nonEmpty() && tvars_cap.nonEmpty()) { 1269 // Let the actual arguments know their bound 1270 args.head.withTypeVar((TypeVar)tvars_cap.head); 1271 args = args.tail; 1272 tvars_cap = tvars_cap.tail; 1273 } 1274 1275 args = type.getTypeArguments(); 1276 List<Type> bounds = bounds_buf.toList(); 1277 1278 while (args.nonEmpty() && bounds.nonEmpty()) { 1279 Type actual = args.head; 1280 if (!isTypeArgErroneous(actual) && 1281 !bounds.head.isErroneous() && 1282 !checkExtends(actual, bounds.head)) { 1283 return args.head; 1284 } 1285 args = args.tail; 1286 bounds = bounds.tail; 1287 } 1288 1289 args = type.getTypeArguments(); 1290 bounds = bounds_buf.toList(); 1291 1292 for (Type arg : types.capture(type).getTypeArguments()) { 1293 if (arg.hasTag(TYPEVAR) && 1294 arg.getUpperBound().isErroneous() && 1295 !bounds.head.isErroneous() && 1296 !isTypeArgErroneous(args.head)) { 1297 return args.head; 1298 } 1299 bounds = bounds.tail; 1300 args = args.tail; 1301 } 1302 1303 return null; 1304 } 1305 //where 1306 boolean isTypeArgErroneous(Type t) { 1307 return isTypeArgErroneous.visit(t); 1308 } 1309 1310 Types.UnaryVisitor<Boolean> isTypeArgErroneous = new Types.UnaryVisitor<Boolean>() { 1311 public Boolean visitType(Type t, Void s) { 1312 return t.isErroneous(); 1313 } 1314 @Override 1315 public Boolean visitTypeVar(TypeVar t, Void s) { 1316 return visit(t.getUpperBound()); 1317 } 1318 @Override 1319 public Boolean visitCapturedType(CapturedType t, Void s) { 1320 return visit(t.getUpperBound()) || 1321 visit(t.getLowerBound()); 1322 } 1323 @Override 1324 public Boolean visitWildcardType(WildcardType t, Void s) { 1325 return visit(t.type); 1326 } 1327 }; 1328 1329 /** Check that given modifiers are legal for given symbol and 1330 * return modifiers together with any implicit modifiers for that symbol. 1331 * Warning: we can't use flags() here since this method 1332 * is called during class enter, when flags() would cause a premature 1333 * completion. 1334 * @param pos Position to be used for error reporting. 1335 * @param flags The set of modifiers given in a definition. 1336 * @param sym The defined symbol. 1337 */ 1338 long checkFlags(DiagnosticPosition pos, long flags, Symbol sym, JCTree tree) { 1339 long mask; 1340 long implicit = 0; 1341 1342 switch (sym.kind) { 1343 case VAR: 1344 if (TreeInfo.isReceiverParam(tree)) 1345 mask = ReceiverParamFlags; 1346 else if (sym.owner.kind != TYP) 1347 mask = LocalVarFlags; 1348 else if ((sym.owner.flags_field & INTERFACE) != 0) 1349 mask = implicit = InterfaceVarFlags; 1350 else { 1351 mask = VarFlags; 1352 if (sym.owner.type.isValueClass() && (flags & STATIC) == 0) { 1353 implicit |= FINAL; 1354 } 1355 } 1356 break; 1357 case MTH: 1358 if (names.isInitOrVNew(sym.name)) { 1359 if ((sym.owner.flags_field & ENUM) != 0) { 1360 // enum constructors cannot be declared public or 1361 // protected and must be implicitly or explicitly 1362 // private 1363 implicit = PRIVATE; 1364 mask = PRIVATE; 1365 } else 1366 mask = ConstructorFlags; 1367 } else if ((sym.owner.flags_field & INTERFACE) != 0) { 1368 if ((sym.owner.flags_field & ANNOTATION) != 0) { 1369 mask = AnnotationTypeElementMask; 1370 implicit = PUBLIC | ABSTRACT; 1371 } else if ((flags & (DEFAULT | STATIC | PRIVATE)) != 0) { 1372 mask = InterfaceMethodMask; 1373 implicit = (flags & PRIVATE) != 0 ? 0 : PUBLIC; 1374 if ((flags & DEFAULT) != 0) { 1375 implicit |= ABSTRACT; 1376 } 1377 } else { 1378 mask = implicit = InterfaceMethodFlags; 1379 } 1380 } else if ((sym.owner.flags_field & RECORD) != 0) { 1381 mask = ((sym.owner.flags_field & VALUE_CLASS) != 0 && (flags & Flags.STATIC) == 0) ? 1382 RecordMethodFlags & ~SYNCHRONIZED : RecordMethodFlags; 1383 } else { 1384 // value objects do not have an associated monitor/lock 1385 mask = ((sym.owner.flags_field & VALUE_CLASS) != 0 && (flags & Flags.STATIC) == 0) ? 1386 MethodFlags & ~SYNCHRONIZED : MethodFlags; 1387 } 1388 if ((flags & STRICTFP) != 0) { 1389 warnOnExplicitStrictfp(pos); 1390 } 1391 // Imply STRICTFP if owner has STRICTFP set. 1392 if (((flags|implicit) & Flags.ABSTRACT) == 0 || 1393 ((flags) & Flags.DEFAULT) != 0) 1394 implicit |= sym.owner.flags_field & STRICTFP; 1395 break; 1396 case TYP: 1397 if (sym.owner.kind.matches(KindSelector.VAL_MTH) || 1398 (sym.isDirectlyOrIndirectlyLocal() && (flags & ANNOTATION) != 0)) { 1399 boolean implicitlyStatic = !sym.isAnonymous() && 1400 ((flags & RECORD) != 0 || (flags & ENUM) != 0 || (flags & INTERFACE) != 0); 1401 boolean staticOrImplicitlyStatic = (flags & STATIC) != 0 || implicitlyStatic; 1402 // local statics are allowed only if records are allowed too 1403 mask = staticOrImplicitlyStatic && allowRecords && (flags & ANNOTATION) == 0 ? ExtendedStaticLocalClassFlags : ExtendedLocalClassFlags; 1404 implicit = implicitlyStatic ? STATIC : implicit; 1405 } else if (sym.owner.kind == TYP) { 1406 // statics in inner classes are allowed only if records are allowed too 1407 mask = ((flags & STATIC) != 0) && allowRecords && (flags & ANNOTATION) == 0 ? ExtendedMemberStaticClassFlags : ExtendedMemberClassFlags; 1408 if (sym.owner.owner.kind == PCK || 1409 (sym.owner.flags_field & STATIC) != 0) { 1410 mask |= STATIC; 1411 } else if (!allowRecords && ((flags & ENUM) != 0 || (flags & RECORD) != 0)) { 1412 log.error(pos, Errors.StaticDeclarationNotAllowedInInnerClasses); 1413 } 1414 // Nested interfaces and enums are always STATIC (Spec ???) 1415 if ((flags & (INTERFACE | ENUM | RECORD)) != 0 ) implicit = STATIC; 1416 } else { 1417 mask = ExtendedClassFlags; 1418 } 1419 // Interfaces are always ABSTRACT 1420 if ((flags & INTERFACE) != 0) implicit |= ABSTRACT; 1421 1422 if ((flags & ENUM) != 0) { 1423 // enums can't be declared abstract, final, sealed or non-sealed or primitive/value 1424 mask &= ~(ABSTRACT | FINAL | SEALED | NON_SEALED | PRIMITIVE_CLASS | VALUE_CLASS); 1425 implicit |= implicitEnumFinalFlag(tree); 1426 } 1427 if ((flags & RECORD) != 0) { 1428 // records can't be declared abstract 1429 mask &= ~ABSTRACT; 1430 implicit |= FINAL; 1431 } 1432 if ((flags & STRICTFP) != 0) { 1433 warnOnExplicitStrictfp(pos); 1434 } 1435 // Imply STRICTFP if owner has STRICTFP set. 1436 implicit |= sym.owner.flags_field & STRICTFP; 1437 1438 // primitive classes are implicitly final value classes. 1439 if ((flags & PRIMITIVE_CLASS) != 0) 1440 implicit |= VALUE_CLASS | FINAL; 1441 1442 // concrete value classes are implicitly final 1443 if ((flags & (ABSTRACT | INTERFACE | VALUE_CLASS)) == VALUE_CLASS) { 1444 implicit |= FINAL; 1445 if ((flags & NON_SEALED) != 0) { 1446 // cant declare a final value class non-sealed 1447 log.error(pos, 1448 Errors.ModNotAllowedHere(asFlagSet(NON_SEALED))); 1449 } 1450 } 1451 1452 // TYPs can't be declared synchronized 1453 mask &= ~SYNCHRONIZED; 1454 break; 1455 default: 1456 throw new AssertionError(); 1457 } 1458 long illegal = flags & ExtendedStandardFlags & ~mask; 1459 if (illegal != 0) { 1460 if ((illegal & INTERFACE) != 0) { 1461 log.error(pos, ((flags & ANNOTATION) != 0) ? Errors.AnnotationDeclNotAllowedHere : Errors.IntfNotAllowedHere); 1462 mask |= INTERFACE; 1463 } 1464 else { 1465 log.error(pos, 1466 Errors.ModNotAllowedHere(asFlagSet(illegal))); 1467 } 1468 } 1469 else if ((sym.kind == TYP || 1470 // ISSUE: Disallowing abstract&private is no longer appropriate 1471 // in the presence of inner classes. Should it be deleted here? 1472 checkDisjoint(pos, flags, 1473 ABSTRACT, 1474 PRIVATE | STATIC | DEFAULT)) 1475 && 1476 checkDisjoint(pos, flags, 1477 STATIC | PRIVATE, 1478 DEFAULT) 1479 && 1480 checkDisjoint(pos, flags, 1481 ABSTRACT | INTERFACE, 1482 FINAL | NATIVE | SYNCHRONIZED | PRIMITIVE_CLASS) 1483 && 1484 checkDisjoint(pos, flags, 1485 IDENTITY_TYPE, 1486 PRIMITIVE_CLASS | VALUE_CLASS) 1487 && 1488 checkDisjoint(pos, flags, 1489 PUBLIC, 1490 PRIVATE | PROTECTED) 1491 && 1492 checkDisjoint(pos, flags, 1493 PRIVATE, 1494 PUBLIC | PROTECTED) 1495 && 1496 checkDisjoint(pos, (flags | implicit), // complain against volatile & implcitly final entities too. 1497 FINAL, 1498 VOLATILE) 1499 && 1500 (sym.kind == TYP || 1501 checkDisjoint(pos, flags, 1502 ABSTRACT | NATIVE, 1503 STRICTFP)) 1504 && checkDisjoint(pos, flags, 1505 FINAL, 1506 SEALED | NON_SEALED) 1507 && checkDisjoint(pos, flags, 1508 SEALED, 1509 FINAL | NON_SEALED) 1510 && checkDisjoint(pos, flags, 1511 SEALED, 1512 ANNOTATION) 1513 && checkDisjoint(pos, flags, 1514 IDENTITY_TYPE, 1515 ANNOTATION) 1516 && checkDisjoint(pos, flags, 1517 VALUE_CLASS, 1518 ANNOTATION) ) { 1519 // skip 1520 } 1521 return flags & (mask | ~ExtendedStandardFlags) | implicit; 1522 } 1523 1524 private void warnOnExplicitStrictfp(DiagnosticPosition pos) { 1525 DiagnosticPosition prevLintPos = deferredLintHandler.setPos(pos); 1526 try { 1527 deferredLintHandler.report(() -> { 1528 if (lint.isEnabled(LintCategory.STRICTFP)) { 1529 log.warning(LintCategory.STRICTFP, 1530 pos, Warnings.Strictfp); } 1531 }); 1532 } finally { 1533 deferredLintHandler.setPos(prevLintPos); 1534 } 1535 } 1536 1537 1538 /** Determine if this enum should be implicitly final. 1539 * 1540 * If the enum has no specialized enum constants, it is final. 1541 * 1542 * If the enum does have specialized enum constants, it is 1543 * <i>not</i> final. 1544 */ 1545 private long implicitEnumFinalFlag(JCTree tree) { 1546 if (!tree.hasTag(CLASSDEF)) return 0; 1547 class SpecialTreeVisitor extends JCTree.Visitor { 1548 boolean specialized; 1549 SpecialTreeVisitor() { 1550 this.specialized = false; 1551 } 1552 1553 @Override 1554 public void visitTree(JCTree tree) { /* no-op */ } 1555 1556 @Override 1557 public void visitVarDef(JCVariableDecl tree) { 1558 if ((tree.mods.flags & ENUM) != 0) { 1559 if (tree.init instanceof JCNewClass newClass && newClass.def != null) { 1560 specialized = true; 1561 } 1562 } 1563 } 1564 } 1565 1566 SpecialTreeVisitor sts = new SpecialTreeVisitor(); 1567 JCClassDecl cdef = (JCClassDecl) tree; 1568 for (JCTree defs: cdef.defs) { 1569 defs.accept(sts); 1570 if (sts.specialized) return allowSealed ? SEALED : 0; 1571 } 1572 return FINAL; 1573 } 1574 1575 /* ************************************************************************* 1576 * Type Validation 1577 **************************************************************************/ 1578 1579 /** Validate a type expression. That is, 1580 * check that all type arguments of a parametric type are within 1581 * their bounds. This must be done in a second phase after type attribution 1582 * since a class might have a subclass as type parameter bound. E.g: 1583 * 1584 * <pre>{@code 1585 * class B<A extends C> { ... } 1586 * class C extends B<C> { ... } 1587 * }</pre> 1588 * 1589 * and we can't make sure that the bound is already attributed because 1590 * of possible cycles. 1591 * 1592 * Visitor method: Validate a type expression, if it is not null, catching 1593 * and reporting any completion failures. 1594 */ 1595 void validate(JCTree tree, Env<AttrContext> env) { 1596 validate(tree, env, true); 1597 } 1598 void validate(JCTree tree, Env<AttrContext> env, boolean checkRaw) { 1599 new Validator(env).validateTree(tree, checkRaw, true); 1600 } 1601 1602 /** Visitor method: Validate a list of type expressions. 1603 */ 1604 void validate(List<? extends JCTree> trees, Env<AttrContext> env) { 1605 for (List<? extends JCTree> l = trees; l.nonEmpty(); l = l.tail) 1606 validate(l.head, env); 1607 } 1608 1609 /** A visitor class for type validation. 1610 */ 1611 class Validator extends JCTree.Visitor { 1612 1613 boolean checkRaw; 1614 boolean isOuter; 1615 Env<AttrContext> env; 1616 1617 Validator(Env<AttrContext> env) { 1618 this.env = env; 1619 } 1620 1621 @Override 1622 public void visitTypeArray(JCArrayTypeTree tree) { 1623 validateTree(tree.elemtype, checkRaw, isOuter); 1624 } 1625 1626 @Override 1627 public void visitTypeApply(JCTypeApply tree) { 1628 if (tree.type.hasTag(CLASS)) { 1629 List<JCExpression> args = tree.arguments; 1630 List<Type> forms = tree.type.tsym.type.getTypeArguments(); 1631 1632 Type incompatibleArg = firstIncompatibleTypeArg(tree.type); 1633 if (incompatibleArg != null) { 1634 for (JCTree arg : tree.arguments) { 1635 if (arg.type == incompatibleArg) { 1636 log.error(arg, Errors.NotWithinBounds(incompatibleArg, forms.head)); 1637 } 1638 forms = forms.tail; 1639 } 1640 } 1641 1642 forms = tree.type.tsym.type.getTypeArguments(); 1643 1644 boolean is_java_lang_Class = tree.type.tsym.flatName() == names.java_lang_Class; 1645 1646 // For matching pairs of actual argument types `a' and 1647 // formal type parameters with declared bound `b' ... 1648 while (args.nonEmpty() && forms.nonEmpty()) { 1649 validateTree(args.head, 1650 !(isOuter && is_java_lang_Class), 1651 false); 1652 args = args.tail; 1653 forms = forms.tail; 1654 } 1655 1656 // Check that this type is either fully parameterized, or 1657 // not parameterized at all. 1658 if (tree.type.getEnclosingType().isRaw()) 1659 log.error(tree.pos(), Errors.ImproperlyFormedTypeInnerRawParam); 1660 if (tree.clazz.hasTag(SELECT)) 1661 visitSelectInternal((JCFieldAccess)tree.clazz); 1662 } 1663 } 1664 1665 @Override 1666 public void visitTypeParameter(JCTypeParameter tree) { 1667 validateTrees(tree.bounds, true, isOuter); 1668 checkClassBounds(tree.pos(), tree.type); 1669 } 1670 1671 @Override 1672 public void visitWildcard(JCWildcard tree) { 1673 if (tree.inner != null) 1674 validateTree(tree.inner, true, isOuter); 1675 } 1676 1677 @Override 1678 public void visitSelect(JCFieldAccess tree) { 1679 if (tree.type.hasTag(CLASS)) { 1680 visitSelectInternal(tree); 1681 1682 // Check that this type is either fully parameterized, or 1683 // not parameterized at all. 1684 if (tree.selected.type.isParameterized() && tree.type.tsym.type.getTypeArguments().nonEmpty()) 1685 log.error(tree.pos(), Errors.ImproperlyFormedTypeParamMissing); 1686 } 1687 } 1688 1689 public void visitSelectInternal(JCFieldAccess tree) { 1690 if (tree.type.tsym.isStatic() && 1691 tree.selected.type.isParameterized() && 1692 (tree.name != names.ref || !tree.type.isReferenceProjection())) { 1693 // The enclosing type is not a class, so we are 1694 // looking at a static member type. However, the 1695 // qualifying expression is parameterized. 1696 // Tolerate the pseudo-select V.ref: V<T>.ref will be static if V<T> is and 1697 // should not be confused as selecting a static member of a parameterized type. 1698 log.error(tree.pos(), Errors.CantSelectStaticClassFromParamType); 1699 } else { 1700 // otherwise validate the rest of the expression 1701 tree.selected.accept(this); 1702 } 1703 } 1704 1705 @Override 1706 public void visitAnnotatedType(JCAnnotatedType tree) { 1707 tree.underlyingType.accept(this); 1708 } 1709 1710 @Override 1711 public void visitTypeIdent(JCPrimitiveTypeTree that) { 1712 if (that.type.hasTag(TypeTag.VOID)) { 1713 log.error(that.pos(), Errors.VoidNotAllowedHere); 1714 } 1715 super.visitTypeIdent(that); 1716 } 1717 1718 /** Default visitor method: do nothing. 1719 */ 1720 @Override 1721 public void visitTree(JCTree tree) { 1722 } 1723 1724 public void validateTree(JCTree tree, boolean checkRaw, boolean isOuter) { 1725 if (tree != null) { 1726 boolean prevCheckRaw = this.checkRaw; 1727 this.checkRaw = checkRaw; 1728 this.isOuter = isOuter; 1729 1730 try { 1731 tree.accept(this); 1732 if (checkRaw) 1733 checkRaw(tree, env); 1734 } catch (CompletionFailure ex) { 1735 completionError(tree.pos(), ex); 1736 } finally { 1737 this.checkRaw = prevCheckRaw; 1738 } 1739 } 1740 } 1741 1742 public void validateTrees(List<? extends JCTree> trees, boolean checkRaw, boolean isOuter) { 1743 for (List<? extends JCTree> l = trees; l.nonEmpty(); l = l.tail) 1744 validateTree(l.head, checkRaw, isOuter); 1745 } 1746 } 1747 1748 void checkRaw(JCTree tree, Env<AttrContext> env) { 1749 if (lint.isEnabled(LintCategory.RAW) && 1750 tree.type.hasTag(CLASS) && 1751 !TreeInfo.isDiamond(tree) && 1752 !withinAnonConstr(env) && 1753 tree.type.isRaw()) { 1754 log.warning(LintCategory.RAW, 1755 tree.pos(), Warnings.RawClassUse(tree.type, tree.type.tsym.type)); 1756 } 1757 } 1758 //where 1759 private boolean withinAnonConstr(Env<AttrContext> env) { 1760 return env.enclClass.name.isEmpty() && 1761 env.enclMethod != null && names.isInitOrVNew(env.enclMethod.name); 1762 } 1763 1764 /* ************************************************************************* 1765 * Exception checking 1766 **************************************************************************/ 1767 1768 /* The following methods treat classes as sets that contain 1769 * the class itself and all their subclasses 1770 */ 1771 1772 /** Is given type a subtype of some of the types in given list? 1773 */ 1774 boolean subset(Type t, List<Type> ts) { 1775 for (List<Type> l = ts; l.nonEmpty(); l = l.tail) 1776 if (types.isSubtype(t, l.head)) return true; 1777 return false; 1778 } 1779 1780 /** Is given type a subtype or supertype of 1781 * some of the types in given list? 1782 */ 1783 boolean intersects(Type t, List<Type> ts) { 1784 for (List<Type> l = ts; l.nonEmpty(); l = l.tail) 1785 if (types.isSubtype(t, l.head) || types.isSubtype(l.head, t)) return true; 1786 return false; 1787 } 1788 1789 /** Add type set to given type list, unless it is a subclass of some class 1790 * in the list. 1791 */ 1792 List<Type> incl(Type t, List<Type> ts) { 1793 return subset(t, ts) ? ts : excl(t, ts).prepend(t); 1794 } 1795 1796 /** Remove type set from type set list. 1797 */ 1798 List<Type> excl(Type t, List<Type> ts) { 1799 if (ts.isEmpty()) { 1800 return ts; 1801 } else { 1802 List<Type> ts1 = excl(t, ts.tail); 1803 if (types.isSubtype(ts.head, t)) return ts1; 1804 else if (ts1 == ts.tail) return ts; 1805 else return ts1.prepend(ts.head); 1806 } 1807 } 1808 1809 /** Form the union of two type set lists. 1810 */ 1811 List<Type> union(List<Type> ts1, List<Type> ts2) { 1812 List<Type> ts = ts1; 1813 for (List<Type> l = ts2; l.nonEmpty(); l = l.tail) 1814 ts = incl(l.head, ts); 1815 return ts; 1816 } 1817 1818 /** Form the difference of two type lists. 1819 */ 1820 List<Type> diff(List<Type> ts1, List<Type> ts2) { 1821 List<Type> ts = ts1; 1822 for (List<Type> l = ts2; l.nonEmpty(); l = l.tail) 1823 ts = excl(l.head, ts); 1824 return ts; 1825 } 1826 1827 /** Form the intersection of two type lists. 1828 */ 1829 public List<Type> intersect(List<Type> ts1, List<Type> ts2) { 1830 List<Type> ts = List.nil(); 1831 for (List<Type> l = ts1; l.nonEmpty(); l = l.tail) 1832 if (subset(l.head, ts2)) ts = incl(l.head, ts); 1833 for (List<Type> l = ts2; l.nonEmpty(); l = l.tail) 1834 if (subset(l.head, ts1)) ts = incl(l.head, ts); 1835 return ts; 1836 } 1837 1838 /** Is exc an exception symbol that need not be declared? 1839 */ 1840 boolean isUnchecked(ClassSymbol exc) { 1841 return 1842 exc.kind == ERR || 1843 exc.isSubClass(syms.errorType.tsym, types) || 1844 exc.isSubClass(syms.runtimeExceptionType.tsym, types); 1845 } 1846 1847 /** Is exc an exception type that need not be declared? 1848 */ 1849 boolean isUnchecked(Type exc) { 1850 return 1851 (exc.hasTag(TYPEVAR)) ? isUnchecked(types.supertype(exc)) : 1852 (exc.hasTag(CLASS)) ? isUnchecked((ClassSymbol)exc.tsym) : 1853 exc.hasTag(BOT); 1854 } 1855 1856 boolean isChecked(Type exc) { 1857 return !isUnchecked(exc); 1858 } 1859 1860 /** Same, but handling completion failures. 1861 */ 1862 boolean isUnchecked(DiagnosticPosition pos, Type exc) { 1863 try { 1864 return isUnchecked(exc); 1865 } catch (CompletionFailure ex) { 1866 completionError(pos, ex); 1867 return true; 1868 } 1869 } 1870 1871 /** Is exc handled by given exception list? 1872 */ 1873 boolean isHandled(Type exc, List<Type> handled) { 1874 return isUnchecked(exc) || subset(exc, handled); 1875 } 1876 1877 /** Return all exceptions in thrown list that are not in handled list. 1878 * @param thrown The list of thrown exceptions. 1879 * @param handled The list of handled exceptions. 1880 */ 1881 List<Type> unhandled(List<Type> thrown, List<Type> handled) { 1882 List<Type> unhandled = List.nil(); 1883 for (List<Type> l = thrown; l.nonEmpty(); l = l.tail) 1884 if (!isHandled(l.head, handled)) unhandled = unhandled.prepend(l.head); 1885 return unhandled; 1886 } 1887 1888 /* ************************************************************************* 1889 * Overriding/Implementation checking 1890 **************************************************************************/ 1891 1892 /** The level of access protection given by a flag set, 1893 * where PRIVATE is highest and PUBLIC is lowest. 1894 */ 1895 static int protection(long flags) { 1896 switch ((short)(flags & AccessFlags)) { 1897 case PRIVATE: return 3; 1898 case PROTECTED: return 1; 1899 default: 1900 case PUBLIC: return 0; 1901 case 0: return 2; 1902 } 1903 } 1904 1905 /** A customized "cannot override" error message. 1906 * @param m The overriding method. 1907 * @param other The overridden method. 1908 * @return An internationalized string. 1909 */ 1910 Fragment cannotOverride(MethodSymbol m, MethodSymbol other) { 1911 Symbol mloc = m.location(); 1912 Symbol oloc = other.location(); 1913 1914 if ((other.owner.flags() & INTERFACE) == 0) 1915 return Fragments.CantOverride(m, mloc, other, oloc); 1916 else if ((m.owner.flags() & INTERFACE) == 0) 1917 return Fragments.CantImplement(m, mloc, other, oloc); 1918 else 1919 return Fragments.ClashesWith(m, mloc, other, oloc); 1920 } 1921 1922 /** A customized "override" warning message. 1923 * @param m The overriding method. 1924 * @param other The overridden method. 1925 * @return An internationalized string. 1926 */ 1927 Fragment uncheckedOverrides(MethodSymbol m, MethodSymbol other) { 1928 Symbol mloc = m.location(); 1929 Symbol oloc = other.location(); 1930 1931 if ((other.owner.flags() & INTERFACE) == 0) 1932 return Fragments.UncheckedOverride(m, mloc, other, oloc); 1933 else if ((m.owner.flags() & INTERFACE) == 0) 1934 return Fragments.UncheckedImplement(m, mloc, other, oloc); 1935 else 1936 return Fragments.UncheckedClashWith(m, mloc, other, oloc); 1937 } 1938 1939 /** A customized "override" warning message. 1940 * @param m The overriding method. 1941 * @param other The overridden method. 1942 * @return An internationalized string. 1943 */ 1944 Fragment varargsOverrides(MethodSymbol m, MethodSymbol other) { 1945 Symbol mloc = m.location(); 1946 Symbol oloc = other.location(); 1947 1948 if ((other.owner.flags() & INTERFACE) == 0) 1949 return Fragments.VarargsOverride(m, mloc, other, oloc); 1950 else if ((m.owner.flags() & INTERFACE) == 0) 1951 return Fragments.VarargsImplement(m, mloc, other, oloc); 1952 else 1953 return Fragments.VarargsClashWith(m, mloc, other, oloc); 1954 } 1955 1956 /** Check that this method conforms with overridden method 'other'. 1957 * where `origin' is the class where checking started. 1958 * Complications: 1959 * (1) Do not check overriding of synthetic methods 1960 * (reason: they might be final). 1961 * todo: check whether this is still necessary. 1962 * (2) Admit the case where an interface proxy throws fewer exceptions 1963 * than the method it implements. Augment the proxy methods with the 1964 * undeclared exceptions in this case. 1965 * (3) When generics are enabled, admit the case where an interface proxy 1966 * has a result type 1967 * extended by the result type of the method it implements. 1968 * Change the proxies result type to the smaller type in this case. 1969 * 1970 * @param tree The tree from which positions 1971 * are extracted for errors. 1972 * @param m The overriding method. 1973 * @param other The overridden method. 1974 * @param origin The class of which the overriding method 1975 * is a member. 1976 */ 1977 void checkOverride(JCTree tree, 1978 MethodSymbol m, 1979 MethodSymbol other, 1980 ClassSymbol origin) { 1981 // Don't check overriding of synthetic methods or by bridge methods. 1982 if ((m.flags() & (SYNTHETIC|BRIDGE)) != 0 || (other.flags() & SYNTHETIC) != 0) { 1983 return; 1984 } 1985 1986 // Error if static method overrides instance method (JLS 8.4.8.2). 1987 if ((m.flags() & STATIC) != 0 && 1988 (other.flags() & STATIC) == 0) { 1989 log.error(TreeInfo.diagnosticPositionFor(m, tree), 1990 Errors.OverrideStatic(cannotOverride(m, other))); 1991 m.flags_field |= BAD_OVERRIDE; 1992 return; 1993 } 1994 1995 // Error if instance method overrides static or final 1996 // method (JLS 8.4.8.1). 1997 if ((other.flags() & FINAL) != 0 || 1998 (m.flags() & STATIC) == 0 && 1999 (other.flags() & STATIC) != 0) { 2000 log.error(TreeInfo.diagnosticPositionFor(m, tree), 2001 Errors.OverrideMeth(cannotOverride(m, other), 2002 asFlagSet(other.flags() & (FINAL | STATIC)))); 2003 m.flags_field |= BAD_OVERRIDE; 2004 return; 2005 } 2006 2007 if ((m.owner.flags() & ANNOTATION) != 0) { 2008 // handled in validateAnnotationMethod 2009 return; 2010 } 2011 2012 // Error if overriding method has weaker access (JLS 8.4.8.3). 2013 if (protection(m.flags()) > protection(other.flags())) { 2014 log.error(TreeInfo.diagnosticPositionFor(m, tree), 2015 (other.flags() & AccessFlags) == 0 ? 2016 Errors.OverrideWeakerAccess(cannotOverride(m, other), 2017 "package") : 2018 Errors.OverrideWeakerAccess(cannotOverride(m, other), 2019 asFlagSet(other.flags() & AccessFlags))); 2020 m.flags_field |= BAD_OVERRIDE; 2021 return; 2022 } 2023 2024 if (shouldCheckPreview(m, other, origin)) { 2025 checkPreview(tree.pos(), m, other); 2026 } 2027 2028 Type mt = types.memberType(origin.type, m); 2029 Type ot = types.memberType(origin.type, other); 2030 // Error if overriding result type is different 2031 // (or, in the case of generics mode, not a subtype) of 2032 // overridden result type. We have to rename any type parameters 2033 // before comparing types. 2034 List<Type> mtvars = mt.getTypeArguments(); 2035 List<Type> otvars = ot.getTypeArguments(); 2036 Type mtres = mt.getReturnType(); 2037 Type otres = types.subst(ot.getReturnType(), otvars, mtvars); 2038 2039 overrideWarner.clear(); 2040 boolean resultTypesOK = 2041 types.returnTypeSubstitutable(mt, ot, otres, overrideWarner); 2042 if (!resultTypesOK) { 2043 if ((m.flags() & STATIC) != 0 && (other.flags() & STATIC) != 0) { 2044 log.error(TreeInfo.diagnosticPositionFor(m, tree), 2045 Errors.OverrideIncompatibleRet(Fragments.CantHide(m, m.location(), other, 2046 other.location()), mtres, otres)); 2047 m.flags_field |= BAD_OVERRIDE; 2048 } else { 2049 log.error(TreeInfo.diagnosticPositionFor(m, tree), 2050 Errors.OverrideIncompatibleRet(cannotOverride(m, other), mtres, otres)); 2051 m.flags_field |= BAD_OVERRIDE; 2052 } 2053 return; 2054 } else if (overrideWarner.hasNonSilentLint(LintCategory.UNCHECKED)) { 2055 warnUnchecked(TreeInfo.diagnosticPositionFor(m, tree), 2056 Warnings.OverrideUncheckedRet(uncheckedOverrides(m, other), mtres, otres)); 2057 } 2058 2059 // Error if overriding method throws an exception not reported 2060 // by overridden method. 2061 List<Type> otthrown = types.subst(ot.getThrownTypes(), otvars, mtvars); 2062 List<Type> unhandledErased = unhandled(mt.getThrownTypes(), types.erasure(otthrown)); 2063 List<Type> unhandledUnerased = unhandled(mt.getThrownTypes(), otthrown); 2064 if (unhandledErased.nonEmpty()) { 2065 log.error(TreeInfo.diagnosticPositionFor(m, tree), 2066 Errors.OverrideMethDoesntThrow(cannotOverride(m, other), unhandledUnerased.head)); 2067 m.flags_field |= BAD_OVERRIDE; 2068 return; 2069 } 2070 else if (unhandledUnerased.nonEmpty()) { 2071 warnUnchecked(TreeInfo.diagnosticPositionFor(m, tree), 2072 Warnings.OverrideUncheckedThrown(cannotOverride(m, other), unhandledUnerased.head)); 2073 return; 2074 } 2075 2076 // Optional warning if varargs don't agree 2077 if ((((m.flags() ^ other.flags()) & Flags.VARARGS) != 0) 2078 && lint.isEnabled(LintCategory.OVERRIDES)) { 2079 log.warning(TreeInfo.diagnosticPositionFor(m, tree), 2080 ((m.flags() & Flags.VARARGS) != 0) 2081 ? Warnings.OverrideVarargsMissing(varargsOverrides(m, other)) 2082 : Warnings.OverrideVarargsExtra(varargsOverrides(m, other))); 2083 } 2084 2085 // Warn if instance method overrides bridge method (compiler spec ??) 2086 if ((other.flags() & BRIDGE) != 0) { 2087 log.warning(TreeInfo.diagnosticPositionFor(m, tree), 2088 Warnings.OverrideBridge(uncheckedOverrides(m, other))); 2089 } 2090 2091 // Warn if a deprecated method overridden by a non-deprecated one. 2092 if (!isDeprecatedOverrideIgnorable(other, origin)) { 2093 Lint prevLint = setLint(lint.augment(m)); 2094 try { 2095 checkDeprecated(() -> TreeInfo.diagnosticPositionFor(m, tree), m, other); 2096 } finally { 2097 setLint(prevLint); 2098 } 2099 } 2100 } 2101 // where 2102 private boolean shouldCheckPreview(MethodSymbol m, MethodSymbol other, ClassSymbol origin) { 2103 if (m.owner != origin || 2104 //performance - only do the expensive checks when the overridden method is a Preview API: 2105 (other.flags() & PREVIEW_API) == 0) { 2106 return false; 2107 } 2108 2109 for (Symbol s : types.membersClosure(origin.type, false).getSymbolsByName(m.name)) { 2110 if (m != s && m.overrides(s, origin, types, false)) { 2111 //only produce preview warnings or errors if "m" immediatelly overrides "other" 2112 //without intermediate overriding methods: 2113 return s == other; 2114 } 2115 } 2116 2117 return false; 2118 } 2119 private boolean isDeprecatedOverrideIgnorable(MethodSymbol m, ClassSymbol origin) { 2120 // If the method, m, is defined in an interface, then ignore the issue if the method 2121 // is only inherited via a supertype and also implemented in the supertype, 2122 // because in that case, we will rediscover the issue when examining the method 2123 // in the supertype. 2124 // If the method, m, is not defined in an interface, then the only time we need to 2125 // address the issue is when the method is the supertype implementation: any other 2126 // case, we will have dealt with when examining the supertype classes 2127 ClassSymbol mc = m.enclClass(); 2128 Type st = types.supertype(origin.type); 2129 if (!st.hasTag(CLASS)) 2130 return true; 2131 MethodSymbol stimpl = m.implementation((ClassSymbol)st.tsym, types, false); 2132 2133 if (mc != null && ((mc.flags() & INTERFACE) != 0)) { 2134 List<Type> intfs = types.interfaces(origin.type); 2135 return (intfs.contains(mc.type) ? false : (stimpl != null)); 2136 } 2137 else 2138 return (stimpl != m); 2139 } 2140 2141 2142 // used to check if there were any unchecked conversions 2143 Warner overrideWarner = new Warner(); 2144 2145 /** Check that a class does not inherit two concrete methods 2146 * with the same signature. 2147 * @param pos Position to be used for error reporting. 2148 * @param site The class type to be checked. 2149 */ 2150 public void checkCompatibleConcretes(DiagnosticPosition pos, Type site) { 2151 Type sup = types.supertype(site); 2152 if (!sup.hasTag(CLASS)) return; 2153 2154 for (Type t1 = sup; 2155 t1.hasTag(CLASS) && t1.tsym.type.isParameterized(); 2156 t1 = types.supertype(t1)) { 2157 for (Symbol s1 : t1.tsym.members().getSymbols(NON_RECURSIVE)) { 2158 if (s1.kind != MTH || 2159 (s1.flags() & (STATIC|SYNTHETIC|BRIDGE)) != 0 || 2160 !s1.isInheritedIn(site.tsym, types) || 2161 ((MethodSymbol)s1).implementation(site.tsym, 2162 types, 2163 true) != s1) 2164 continue; 2165 Type st1 = types.memberType(t1, s1); 2166 int s1ArgsLength = st1.getParameterTypes().length(); 2167 if (st1 == s1.type) continue; 2168 2169 for (Type t2 = sup; 2170 t2.hasTag(CLASS); 2171 t2 = types.supertype(t2)) { 2172 for (Symbol s2 : t2.tsym.members().getSymbolsByName(s1.name)) { 2173 if (s2 == s1 || 2174 s2.kind != MTH || 2175 (s2.flags() & (STATIC|SYNTHETIC|BRIDGE)) != 0 || 2176 s2.type.getParameterTypes().length() != s1ArgsLength || 2177 !s2.isInheritedIn(site.tsym, types) || 2178 ((MethodSymbol)s2).implementation(site.tsym, 2179 types, 2180 true) != s2) 2181 continue; 2182 Type st2 = types.memberType(t2, s2); 2183 if (types.overrideEquivalent(st1, st2)) 2184 log.error(pos, 2185 Errors.ConcreteInheritanceConflict(s1, t1, s2, t2, sup)); 2186 } 2187 } 2188 } 2189 } 2190 } 2191 2192 /** Check that classes (or interfaces) do not each define an abstract 2193 * method with same name and arguments but incompatible return types. 2194 * @param pos Position to be used for error reporting. 2195 * @param t1 The first argument type. 2196 * @param t2 The second argument type. 2197 */ 2198 public boolean checkCompatibleAbstracts(DiagnosticPosition pos, 2199 Type t1, 2200 Type t2, 2201 Type site) { 2202 if ((site.tsym.flags() & COMPOUND) != 0) { 2203 // special case for intersections: need to eliminate wildcards in supertypes 2204 t1 = types.capture(t1); 2205 t2 = types.capture(t2); 2206 } 2207 return firstIncompatibility(pos, t1, t2, site) == null; 2208 } 2209 2210 /** Return the first method which is defined with same args 2211 * but different return types in two given interfaces, or null if none 2212 * exists. 2213 * @param t1 The first type. 2214 * @param t2 The second type. 2215 * @param site The most derived type. 2216 * @return symbol from t2 that conflicts with one in t1. 2217 */ 2218 private Symbol firstIncompatibility(DiagnosticPosition pos, Type t1, Type t2, Type site) { 2219 Map<TypeSymbol,Type> interfaces1 = new HashMap<>(); 2220 closure(t1, interfaces1); 2221 Map<TypeSymbol,Type> interfaces2; 2222 if (t1 == t2) 2223 interfaces2 = interfaces1; 2224 else 2225 closure(t2, interfaces1, interfaces2 = new HashMap<>()); 2226 2227 for (Type t3 : interfaces1.values()) { 2228 for (Type t4 : interfaces2.values()) { 2229 Symbol s = firstDirectIncompatibility(pos, t3, t4, site); 2230 if (s != null) return s; 2231 } 2232 } 2233 return null; 2234 } 2235 2236 /** Compute all the supertypes of t, indexed by type symbol. */ 2237 private void closure(Type t, Map<TypeSymbol,Type> typeMap) { 2238 if (!t.hasTag(CLASS)) return; 2239 if (typeMap.put(t.tsym, t) == null) { 2240 closure(types.supertype(t), typeMap); 2241 for (Type i : types.interfaces(t)) 2242 closure(i, typeMap); 2243 } 2244 } 2245 2246 /** Compute all the supertypes of t, indexed by type symbol (except those in typesSkip). */ 2247 private void closure(Type t, Map<TypeSymbol,Type> typesSkip, Map<TypeSymbol,Type> typeMap) { 2248 if (!t.hasTag(CLASS)) return; 2249 if (typesSkip.get(t.tsym) != null) return; 2250 if (typeMap.put(t.tsym, t) == null) { 2251 closure(types.supertype(t), typesSkip, typeMap); 2252 for (Type i : types.interfaces(t)) 2253 closure(i, typesSkip, typeMap); 2254 } 2255 } 2256 2257 /** Return the first method in t2 that conflicts with a method from t1. */ 2258 private Symbol firstDirectIncompatibility(DiagnosticPosition pos, Type t1, Type t2, Type site) { 2259 for (Symbol s1 : t1.tsym.members().getSymbols(NON_RECURSIVE)) { 2260 Type st1 = null; 2261 if (s1.kind != MTH || !s1.isInheritedIn(site.tsym, types) || 2262 (s1.flags() & SYNTHETIC) != 0) continue; 2263 Symbol impl = ((MethodSymbol)s1).implementation(site.tsym, types, false); 2264 if (impl != null && (impl.flags() & ABSTRACT) == 0) continue; 2265 for (Symbol s2 : t2.tsym.members().getSymbolsByName(s1.name)) { 2266 if (s1 == s2) continue; 2267 if (s2.kind != MTH || !s2.isInheritedIn(site.tsym, types) || 2268 (s2.flags() & SYNTHETIC) != 0) continue; 2269 if (st1 == null) st1 = types.memberType(t1, s1); 2270 Type st2 = types.memberType(t2, s2); 2271 if (types.overrideEquivalent(st1, st2)) { 2272 List<Type> tvars1 = st1.getTypeArguments(); 2273 List<Type> tvars2 = st2.getTypeArguments(); 2274 Type rt1 = st1.getReturnType(); 2275 Type rt2 = types.subst(st2.getReturnType(), tvars2, tvars1); 2276 boolean compat = 2277 types.isSameType(rt1, rt2) || 2278 !rt1.isPrimitiveOrVoid() && 2279 !rt2.isPrimitiveOrVoid() && 2280 (types.covariantReturnType(rt1, rt2, types.noWarnings) || 2281 types.covariantReturnType(rt2, rt1, types.noWarnings)) || 2282 checkCommonOverriderIn(s1,s2,site); 2283 if (!compat) { 2284 if (types.isSameType(t1, t2)) { 2285 log.error(pos, Errors.IncompatibleDiffRetSameType(t1, 2286 s2.name, types.memberType(t2, s2).getParameterTypes())); 2287 } else { 2288 log.error(pos, Errors.TypesIncompatible(t1, t2, 2289 Fragments.IncompatibleDiffRet(s2.name, types.memberType(t2, s2).getParameterTypes()))); 2290 } 2291 return s2; 2292 } 2293 } else if (checkNameClash((ClassSymbol)site.tsym, s1, s2) && 2294 !checkCommonOverriderIn(s1, s2, site)) { 2295 log.error(pos, Errors.NameClashSameErasureNoOverride( 2296 s1.name, types.memberType(site, s1).asMethodType().getParameterTypes(), s1.location(), 2297 s2.name, types.memberType(site, s2).asMethodType().getParameterTypes(), s2.location())); 2298 return s2; 2299 } 2300 } 2301 } 2302 return null; 2303 } 2304 //WHERE 2305 boolean checkCommonOverriderIn(Symbol s1, Symbol s2, Type site) { 2306 Map<TypeSymbol,Type> supertypes = new HashMap<>(); 2307 Type st1 = types.memberType(site, s1); 2308 Type st2 = types.memberType(site, s2); 2309 closure(site, supertypes); 2310 for (Type t : supertypes.values()) { 2311 for (Symbol s3 : t.tsym.members().getSymbolsByName(s1.name)) { 2312 if (s3 == s1 || s3 == s2 || s3.kind != MTH || (s3.flags() & (BRIDGE|SYNTHETIC)) != 0) continue; 2313 Type st3 = types.memberType(site,s3); 2314 if (types.overrideEquivalent(st3, st1) && 2315 types.overrideEquivalent(st3, st2) && 2316 types.returnTypeSubstitutable(st3, st1) && 2317 types.returnTypeSubstitutable(st3, st2)) { 2318 return true; 2319 } 2320 } 2321 } 2322 return false; 2323 } 2324 2325 /** Check that a given method conforms with any method it overrides. 2326 * @param tree The tree from which positions are extracted 2327 * for errors. 2328 * @param m The overriding method. 2329 */ 2330 void checkOverride(Env<AttrContext> env, JCMethodDecl tree, MethodSymbol m) { 2331 ClassSymbol origin = (ClassSymbol)m.owner; 2332 if ((origin.flags() & ENUM) != 0 && names.finalize.equals(m.name)) { 2333 if (m.overrides(syms.enumFinalFinalize, origin, types, false)) { 2334 log.error(tree.pos(), Errors.EnumNoFinalize); 2335 return; 2336 } 2337 } 2338 if (allowRecords && origin.isRecord()) { 2339 // let's find out if this is a user defined accessor in which case the @Override annotation is acceptable 2340 Optional<? extends RecordComponent> recordComponent = origin.getRecordComponents().stream() 2341 .filter(rc -> rc.accessor == tree.sym && (rc.accessor.flags_field & GENERATED_MEMBER) == 0).findFirst(); 2342 if (recordComponent.isPresent()) { 2343 return; 2344 } 2345 } 2346 2347 for (Type t = origin.type; t.hasTag(CLASS); 2348 t = types.supertype(t)) { 2349 if (t != origin.type) { 2350 checkOverride(tree, t, origin, m); 2351 } 2352 for (Type t2 : types.interfaces(t)) { 2353 checkOverride(tree, t2, origin, m); 2354 } 2355 } 2356 2357 final boolean explicitOverride = m.attribute(syms.overrideType.tsym) != null; 2358 // Check if this method must override a super method due to being annotated with @Override 2359 // or by virtue of being a member of a diamond inferred anonymous class. Latter case is to 2360 // be treated "as if as they were annotated" with @Override. 2361 boolean mustOverride = explicitOverride || 2362 (env.info.isAnonymousDiamond && !m.isInitOrVNew() && !m.isPrivate()); 2363 if (mustOverride && !isOverrider(m)) { 2364 DiagnosticPosition pos = tree.pos(); 2365 for (JCAnnotation a : tree.getModifiers().annotations) { 2366 if (a.annotationType.type.tsym == syms.overrideType.tsym) { 2367 pos = a.pos(); 2368 break; 2369 } 2370 } 2371 log.error(pos, 2372 explicitOverride ? (m.isStatic() ? Errors.StaticMethodsCannotBeAnnotatedWithOverride : Errors.MethodDoesNotOverrideSuperclass) : 2373 Errors.AnonymousDiamondMethodDoesNotOverrideSuperclass(Fragments.DiamondAnonymousMethodsImplicitlyOverride)); 2374 } 2375 } 2376 2377 void checkOverride(JCTree tree, Type site, ClassSymbol origin, MethodSymbol m) { 2378 TypeSymbol c = site.tsym; 2379 for (Symbol sym : c.members().getSymbolsByName(m.name)) { 2380 if (m.overrides(sym, origin, types, false)) { 2381 if ((sym.flags() & ABSTRACT) == 0) { 2382 checkOverride(tree, m, (MethodSymbol)sym, origin); 2383 } 2384 } 2385 } 2386 } 2387 2388 private Predicate<Symbol> equalsHasCodeFilter = s -> MethodSymbol.implementation_filter.test(s) && 2389 (s.flags() & BAD_OVERRIDE) == 0; 2390 2391 public void checkClassOverrideEqualsAndHashIfNeeded(DiagnosticPosition pos, 2392 ClassSymbol someClass) { 2393 /* At present, annotations cannot possibly have a method that is override 2394 * equivalent with Object.equals(Object) but in any case the condition is 2395 * fine for completeness. 2396 */ 2397 if (someClass == (ClassSymbol)syms.objectType.tsym || 2398 someClass.isInterface() || someClass.isEnum() || 2399 (someClass.flags() & ANNOTATION) != 0 || 2400 (someClass.flags() & ABSTRACT) != 0) return; 2401 //anonymous inner classes implementing interfaces need especial treatment 2402 if (someClass.isAnonymous()) { 2403 List<Type> interfaces = types.interfaces(someClass.type); 2404 if (interfaces != null && !interfaces.isEmpty() && 2405 interfaces.head.tsym == syms.comparatorType.tsym) return; 2406 } 2407 checkClassOverrideEqualsAndHash(pos, someClass); 2408 } 2409 2410 private void checkClassOverrideEqualsAndHash(DiagnosticPosition pos, 2411 ClassSymbol someClass) { 2412 if (lint.isEnabled(LintCategory.OVERRIDES)) { 2413 MethodSymbol equalsAtObject = (MethodSymbol)syms.objectType 2414 .tsym.members().findFirst(names.equals); 2415 MethodSymbol hashCodeAtObject = (MethodSymbol)syms.objectType 2416 .tsym.members().findFirst(names.hashCode); 2417 MethodSymbol equalsImpl = types.implementation(equalsAtObject, 2418 someClass, false, equalsHasCodeFilter); 2419 boolean overridesEquals = equalsImpl != null && 2420 equalsImpl.owner == someClass; 2421 boolean overridesHashCode = types.implementation(hashCodeAtObject, 2422 someClass, false, equalsHasCodeFilter) != hashCodeAtObject; 2423 2424 if (overridesEquals && !overridesHashCode) { 2425 log.warning(LintCategory.OVERRIDES, pos, 2426 Warnings.OverrideEqualsButNotHashcode(someClass)); 2427 } 2428 } 2429 } 2430 2431 public void checkModuleName (JCModuleDecl tree) { 2432 Name moduleName = tree.sym.name; 2433 Assert.checkNonNull(moduleName); 2434 if (lint.isEnabled(LintCategory.MODULE)) { 2435 JCExpression qualId = tree.qualId; 2436 while (qualId != null) { 2437 Name componentName; 2438 DiagnosticPosition pos; 2439 switch (qualId.getTag()) { 2440 case SELECT: 2441 JCFieldAccess selectNode = ((JCFieldAccess) qualId); 2442 componentName = selectNode.name; 2443 pos = selectNode.pos(); 2444 qualId = selectNode.selected; 2445 break; 2446 case IDENT: 2447 componentName = ((JCIdent) qualId).name; 2448 pos = qualId.pos(); 2449 qualId = null; 2450 break; 2451 default: 2452 throw new AssertionError("Unexpected qualified identifier: " + qualId.toString()); 2453 } 2454 if (componentName != null) { 2455 String moduleNameComponentString = componentName.toString(); 2456 int nameLength = moduleNameComponentString.length(); 2457 if (nameLength > 0 && Character.isDigit(moduleNameComponentString.charAt(nameLength - 1))) { 2458 log.warning(Lint.LintCategory.MODULE, pos, Warnings.PoorChoiceForModuleName(componentName)); 2459 } 2460 } 2461 } 2462 } 2463 } 2464 2465 private boolean checkNameClash(ClassSymbol origin, Symbol s1, Symbol s2) { 2466 ClashFilter cf = new ClashFilter(origin.type); 2467 return (cf.test(s1) && 2468 cf.test(s2) && 2469 types.hasSameArgs(s1.erasure(types), s2.erasure(types))); 2470 } 2471 2472 2473 /** Check that all abstract members of given class have definitions. 2474 * @param pos Position to be used for error reporting. 2475 * @param c The class. 2476 */ 2477 void checkAllDefined(DiagnosticPosition pos, ClassSymbol c) { 2478 MethodSymbol undef = types.firstUnimplementedAbstract(c); 2479 if (undef != null) { 2480 MethodSymbol undef1 = 2481 new MethodSymbol(undef.flags(), undef.name, 2482 types.memberType(c.type, undef), undef.owner); 2483 log.error(pos, 2484 Errors.DoesNotOverrideAbstract(c, undef1, undef1.location())); 2485 } 2486 } 2487 2488 // A primitive class cannot contain a field of its own type either or indirectly. 2489 void checkNonCyclicMembership(JCClassDecl tree) { 2490 if (allowPrimitiveClasses) { 2491 Assert.check((tree.sym.flags_field & LOCKED) == 0); 2492 try { 2493 tree.sym.flags_field |= LOCKED; 2494 for (List<? extends JCTree> l = tree.defs; l.nonEmpty(); l = l.tail) { 2495 if (l.head.hasTag(VARDEF)) { 2496 JCVariableDecl field = (JCVariableDecl) l.head; 2497 if (cyclePossible(field.sym)) { 2498 checkNonCyclicMembership((ClassSymbol) field.type.tsym, field.pos()); 2499 } 2500 } 2501 } 2502 } finally { 2503 tree.sym.flags_field &= ~LOCKED; 2504 } 2505 } 2506 } 2507 // where 2508 private void checkNonCyclicMembership(ClassSymbol c, DiagnosticPosition pos) { 2509 if ((c.flags_field & LOCKED) != 0) { 2510 log.error(pos, Errors.CyclicPrimitiveClassMembership(c)); 2511 return; 2512 } 2513 try { 2514 c.flags_field |= LOCKED; 2515 for (Symbol fld : c.members().getSymbols(s -> s.kind == VAR && cyclePossible((VarSymbol) s), NON_RECURSIVE)) { 2516 checkNonCyclicMembership((ClassSymbol) fld.type.tsym, pos); 2517 } 2518 } finally { 2519 c.flags_field &= ~LOCKED; 2520 } 2521 } 2522 // where 2523 private boolean cyclePossible(VarSymbol symbol) { 2524 return (symbol.flags() & STATIC) == 0 && allowPrimitiveClasses && symbol.type.isPrimitiveClass(); 2525 } 2526 2527 void checkNonCyclicDecl(JCClassDecl tree) { 2528 CycleChecker cc = new CycleChecker(); 2529 cc.scan(tree); 2530 if (!cc.errorFound && !cc.partialCheck) { 2531 tree.sym.flags_field |= ACYCLIC; 2532 } 2533 } 2534 2535 class CycleChecker extends TreeScanner { 2536 2537 Set<Symbol> seenClasses = new HashSet<>(); 2538 boolean errorFound = false; 2539 boolean partialCheck = false; 2540 2541 private void checkSymbol(DiagnosticPosition pos, Symbol sym) { 2542 if (sym != null && sym.kind == TYP) { 2543 Env<AttrContext> classEnv = enter.getEnv((TypeSymbol)sym); 2544 if (classEnv != null) { 2545 DiagnosticSource prevSource = log.currentSource(); 2546 try { 2547 log.useSource(classEnv.toplevel.sourcefile); 2548 scan(classEnv.tree); 2549 } 2550 finally { 2551 log.useSource(prevSource.getFile()); 2552 } 2553 } else if (sym.kind == TYP) { 2554 checkClass(pos, sym, List.nil()); 2555 } 2556 } else if (sym == null || sym.kind != PCK) { 2557 //not completed yet 2558 partialCheck = true; 2559 } 2560 } 2561 2562 @Override 2563 public void visitSelect(JCFieldAccess tree) { 2564 super.visitSelect(tree); 2565 checkSymbol(tree.pos(), tree.sym); 2566 } 2567 2568 @Override 2569 public void visitIdent(JCIdent tree) { 2570 checkSymbol(tree.pos(), tree.sym); 2571 } 2572 2573 @Override 2574 public void visitTypeApply(JCTypeApply tree) { 2575 scan(tree.clazz); 2576 } 2577 2578 @Override 2579 public void visitTypeArray(JCArrayTypeTree tree) { 2580 scan(tree.elemtype); 2581 } 2582 2583 @Override 2584 public void visitClassDef(JCClassDecl tree) { 2585 List<JCTree> supertypes = List.nil(); 2586 if (tree.getExtendsClause() != null) { 2587 supertypes = supertypes.prepend(tree.getExtendsClause()); 2588 } 2589 if (tree.getImplementsClause() != null) { 2590 for (JCTree intf : tree.getImplementsClause()) { 2591 supertypes = supertypes.prepend(intf); 2592 } 2593 } 2594 checkClass(tree.pos(), tree.sym, supertypes); 2595 } 2596 2597 void checkClass(DiagnosticPosition pos, Symbol c, List<JCTree> supertypes) { 2598 if ((c.flags_field & ACYCLIC) != 0) 2599 return; 2600 if (seenClasses.contains(c)) { 2601 errorFound = true; 2602 noteCyclic(pos, (ClassSymbol)c); 2603 } else if (!c.type.isErroneous()) { 2604 try { 2605 seenClasses.add(c); 2606 if (c.type.hasTag(CLASS)) { 2607 if (supertypes.nonEmpty()) { 2608 scan(supertypes); 2609 } 2610 else { 2611 ClassType ct = (ClassType)c.type; 2612 if (ct.supertype_field == null || 2613 ct.interfaces_field == null) { 2614 //not completed yet 2615 partialCheck = true; 2616 return; 2617 } 2618 checkSymbol(pos, ct.supertype_field.tsym); 2619 for (Type intf : ct.interfaces_field) { 2620 checkSymbol(pos, intf.tsym); 2621 } 2622 } 2623 if (c.owner.kind == TYP) { 2624 checkSymbol(pos, c.owner); 2625 } 2626 } 2627 } finally { 2628 seenClasses.remove(c); 2629 } 2630 } 2631 } 2632 } 2633 2634 /** Check for cyclic references. Issue an error if the 2635 * symbol of the type referred to has a LOCKED flag set. 2636 * 2637 * @param pos Position to be used for error reporting. 2638 * @param t The type referred to. 2639 */ 2640 void checkNonCyclic(DiagnosticPosition pos, Type t) { 2641 checkNonCyclicInternal(pos, t); 2642 } 2643 2644 2645 void checkNonCyclic(DiagnosticPosition pos, TypeVar t) { 2646 checkNonCyclic1(pos, t, List.nil()); 2647 } 2648 2649 private void checkNonCyclic1(DiagnosticPosition pos, Type t, List<TypeVar> seen) { 2650 final TypeVar tv; 2651 if (t.hasTag(TYPEVAR) && (t.tsym.flags() & UNATTRIBUTED) != 0) 2652 return; 2653 if (seen.contains(t)) { 2654 tv = (TypeVar)t; 2655 tv.setUpperBound(types.createErrorType(t)); 2656 log.error(pos, Errors.CyclicInheritance(t)); 2657 } else if (t.hasTag(TYPEVAR)) { 2658 tv = (TypeVar)t; 2659 seen = seen.prepend(tv); 2660 for (Type b : types.getBounds(tv)) 2661 checkNonCyclic1(pos, b, seen); 2662 } 2663 } 2664 2665 /** Check for cyclic references. Issue an error if the 2666 * symbol of the type referred to has a LOCKED flag set. 2667 * 2668 * @param pos Position to be used for error reporting. 2669 * @param t The type referred to. 2670 * @returns True if the check completed on all attributed classes 2671 */ 2672 private boolean checkNonCyclicInternal(DiagnosticPosition pos, Type t) { 2673 boolean complete = true; // was the check complete? 2674 //- System.err.println("checkNonCyclicInternal("+t+");");//DEBUG 2675 Symbol c = t.tsym; 2676 if ((c.flags_field & ACYCLIC) != 0) return true; 2677 2678 if ((c.flags_field & LOCKED) != 0) { 2679 noteCyclic(pos, (ClassSymbol)c); 2680 } else if (!c.type.isErroneous()) { 2681 try { 2682 c.flags_field |= LOCKED; 2683 if (c.type.hasTag(CLASS)) { 2684 ClassType clazz = (ClassType)c.type; 2685 if (clazz.interfaces_field != null) 2686 for (List<Type> l=clazz.interfaces_field; l.nonEmpty(); l=l.tail) 2687 complete &= checkNonCyclicInternal(pos, l.head); 2688 if (clazz.supertype_field != null) { 2689 Type st = clazz.supertype_field; 2690 if (st != null && st.hasTag(CLASS)) 2691 complete &= checkNonCyclicInternal(pos, st); 2692 } 2693 if (c.owner.kind == TYP) 2694 complete &= checkNonCyclicInternal(pos, c.owner.type); 2695 } 2696 } finally { 2697 c.flags_field &= ~LOCKED; 2698 } 2699 } 2700 if (complete) 2701 complete = ((c.flags_field & UNATTRIBUTED) == 0) && c.isCompleted(); 2702 if (complete) c.flags_field |= ACYCLIC; 2703 return complete; 2704 } 2705 2706 /** Note that we found an inheritance cycle. */ 2707 private void noteCyclic(DiagnosticPosition pos, ClassSymbol c) { 2708 log.error(pos, Errors.CyclicInheritance(c)); 2709 for (List<Type> l=types.interfaces(c.type); l.nonEmpty(); l=l.tail) 2710 l.head = types.createErrorType((ClassSymbol)l.head.tsym, Type.noType); 2711 Type st = types.supertype(c.type); 2712 if (st.hasTag(CLASS)) 2713 ((ClassType)c.type).supertype_field = types.createErrorType((ClassSymbol)st.tsym, Type.noType); 2714 c.type = types.createErrorType(c, c.type); 2715 c.flags_field |= ACYCLIC; 2716 } 2717 2718 /** Check that all methods which implement some 2719 * method conform to the method they implement. 2720 * @param tree The class definition whose members are checked. 2721 */ 2722 void checkImplementations(JCClassDecl tree) { 2723 checkImplementations(tree, tree.sym, tree.sym); 2724 } 2725 //where 2726 /** Check that all methods which implement some 2727 * method in `ic' conform to the method they implement. 2728 */ 2729 void checkImplementations(JCTree tree, ClassSymbol origin, ClassSymbol ic) { 2730 for (List<Type> l = types.closure(ic.type); l.nonEmpty(); l = l.tail) { 2731 ClassSymbol lc = (ClassSymbol)l.head.tsym; 2732 if ((lc.flags() & ABSTRACT) != 0) { 2733 for (Symbol sym : lc.members().getSymbols(NON_RECURSIVE)) { 2734 if (sym.kind == MTH && 2735 (sym.flags() & (STATIC|ABSTRACT)) == ABSTRACT) { 2736 MethodSymbol absmeth = (MethodSymbol)sym; 2737 MethodSymbol implmeth = absmeth.implementation(origin, types, false); 2738 if (implmeth != null && implmeth != absmeth && 2739 (implmeth.owner.flags() & INTERFACE) == 2740 (origin.flags() & INTERFACE)) { 2741 // don't check if implmeth is in a class, yet 2742 // origin is an interface. This case arises only 2743 // if implmeth is declared in Object. The reason is 2744 // that interfaces really don't inherit from 2745 // Object it's just that the compiler represents 2746 // things that way. 2747 checkOverride(tree, implmeth, absmeth, origin); 2748 } 2749 } 2750 } 2751 } 2752 } 2753 } 2754 2755 /** Check that all abstract methods implemented by a class are 2756 * mutually compatible. 2757 * @param pos Position to be used for error reporting. 2758 * @param c The class whose interfaces are checked. 2759 */ 2760 void checkCompatibleSupertypes(DiagnosticPosition pos, Type c) { 2761 List<Type> supertypes = types.interfaces(c); 2762 Type supertype = types.supertype(c); 2763 if (supertype.hasTag(CLASS) && 2764 (supertype.tsym.flags() & ABSTRACT) != 0) 2765 supertypes = supertypes.prepend(supertype); 2766 for (List<Type> l = supertypes; l.nonEmpty(); l = l.tail) { 2767 if (!l.head.getTypeArguments().isEmpty() && 2768 !checkCompatibleAbstracts(pos, l.head, l.head, c)) 2769 return; 2770 for (List<Type> m = supertypes; m != l; m = m.tail) 2771 if (!checkCompatibleAbstracts(pos, l.head, m.head, c)) 2772 return; 2773 } 2774 checkCompatibleConcretes(pos, c); 2775 2776 boolean cIsValue = (c.tsym.flags() & VALUE_CLASS) != 0; 2777 boolean cHasIdentity = (c.tsym.flags() & IDENTITY_TYPE) != 0; 2778 Type identitySuper = null, valueSuper = null; 2779 for (Type t : types.closure(c)) { 2780 if (t != c) { 2781 if ((t.tsym.flags() & IDENTITY_TYPE) != 0) 2782 identitySuper = t; 2783 else if ((t.tsym.flags() & VALUE_CLASS) != 0) 2784 valueSuper = t; 2785 if (cIsValue && identitySuper != null) { 2786 log.error(pos, Errors.ValueTypeHasIdentitySuperType(c, identitySuper)); 2787 break; 2788 } else if (cHasIdentity && valueSuper != null) { 2789 log.error(pos, Errors.IdentityTypeHasValueSuperType(c, valueSuper)); 2790 break; 2791 } else if (identitySuper != null && valueSuper != null) { 2792 log.error(pos, Errors.MutuallyIncompatibleSupers(c, identitySuper, valueSuper)); 2793 break; 2794 } 2795 } 2796 } 2797 } 2798 2799 /** Check that all non-override equivalent methods accessible from 'site' 2800 * are mutually compatible (JLS 8.4.8/9.4.1). 2801 * 2802 * @param pos Position to be used for error reporting. 2803 * @param site The class whose methods are checked. 2804 * @param sym The method symbol to be checked. 2805 */ 2806 void checkOverrideClashes(DiagnosticPosition pos, Type site, MethodSymbol sym) { 2807 ClashFilter cf = new ClashFilter(site); 2808 //for each method m1 that is overridden (directly or indirectly) 2809 //by method 'sym' in 'site'... 2810 2811 List<MethodSymbol> potentiallyAmbiguousList = List.nil(); 2812 boolean overridesAny = false; 2813 ArrayList<Symbol> symbolsByName = new ArrayList<>(); 2814 types.membersClosure(site, false).getSymbolsByName(sym.name, cf).forEach(symbolsByName::add); 2815 for (Symbol m1 : symbolsByName) { 2816 if (!sym.overrides(m1, site.tsym, types, false)) { 2817 if (m1 == sym) { 2818 continue; 2819 } 2820 2821 if (!overridesAny) { 2822 potentiallyAmbiguousList = potentiallyAmbiguousList.prepend((MethodSymbol)m1); 2823 } 2824 continue; 2825 } 2826 2827 if (m1 != sym) { 2828 overridesAny = true; 2829 potentiallyAmbiguousList = List.nil(); 2830 } 2831 2832 //...check each method m2 that is a member of 'site' 2833 for (Symbol m2 : symbolsByName) { 2834 if (m2 == m1) continue; 2835 //if (i) the signature of 'sym' is not a subsignature of m1 (seen as 2836 //a member of 'site') and (ii) m1 has the same erasure as m2, issue an error 2837 if (!types.isSubSignature(sym.type, types.memberType(site, m2)) && 2838 types.hasSameArgs(m2.erasure(types), m1.erasure(types))) { 2839 sym.flags_field |= CLASH; 2840 if (m1 == sym) { 2841 log.error(pos, Errors.NameClashSameErasureNoOverride( 2842 m1.name, types.memberType(site, m1).asMethodType().getParameterTypes(), m1.location(), 2843 m2.name, types.memberType(site, m2).asMethodType().getParameterTypes(), m2.location())); 2844 } else { 2845 ClassType ct = (ClassType)site; 2846 String kind = ct.isInterface() ? "interface" : "class"; 2847 log.error(pos, Errors.NameClashSameErasureNoOverride1( 2848 kind, 2849 ct.tsym.name, 2850 m1.name, 2851 types.memberType(site, m1).asMethodType().getParameterTypes(), 2852 m1.location(), 2853 m2.name, 2854 types.memberType(site, m2).asMethodType().getParameterTypes(), 2855 m2.location())); 2856 } 2857 return; 2858 } 2859 } 2860 } 2861 2862 if (!overridesAny) { 2863 for (MethodSymbol m: potentiallyAmbiguousList) { 2864 checkPotentiallyAmbiguousOverloads(pos, site, sym, m); 2865 } 2866 } 2867 } 2868 2869 /** Check that all static methods accessible from 'site' are 2870 * mutually compatible (JLS 8.4.8). 2871 * 2872 * @param pos Position to be used for error reporting. 2873 * @param site The class whose methods are checked. 2874 * @param sym The method symbol to be checked. 2875 */ 2876 void checkHideClashes(DiagnosticPosition pos, Type site, MethodSymbol sym) { 2877 ClashFilter cf = new ClashFilter(site); 2878 //for each method m1 that is a member of 'site'... 2879 for (Symbol s : types.membersClosure(site, true).getSymbolsByName(sym.name, cf)) { 2880 //if (i) the signature of 'sym' is not a subsignature of m1 (seen as 2881 //a member of 'site') and (ii) 'sym' has the same erasure as m1, issue an error 2882 if (!types.isSubSignature(sym.type, types.memberType(site, s))) { 2883 if (types.hasSameArgs(s.erasure(types), sym.erasure(types))) { 2884 log.error(pos, 2885 Errors.NameClashSameErasureNoHide(sym, sym.location(), s, s.location())); 2886 return; 2887 } else { 2888 checkPotentiallyAmbiguousOverloads(pos, site, sym, (MethodSymbol)s); 2889 } 2890 } 2891 } 2892 } 2893 2894 //where 2895 private class ClashFilter implements Predicate<Symbol> { 2896 2897 Type site; 2898 2899 ClashFilter(Type site) { 2900 this.site = site; 2901 } 2902 2903 boolean shouldSkip(Symbol s) { 2904 return (s.flags() & CLASH) != 0 && 2905 s.owner == site.tsym; 2906 } 2907 2908 @Override 2909 public boolean test(Symbol s) { 2910 return s.kind == MTH && 2911 (s.flags() & SYNTHETIC) == 0 && 2912 !shouldSkip(s) && 2913 s.isInheritedIn(site.tsym, types) && 2914 !s.isInitOrVNew(); 2915 } 2916 } 2917 2918 void checkDefaultMethodClashes(DiagnosticPosition pos, Type site) { 2919 DefaultMethodClashFilter dcf = new DefaultMethodClashFilter(site); 2920 for (Symbol m : types.membersClosure(site, false).getSymbols(dcf)) { 2921 Assert.check(m.kind == MTH); 2922 List<MethodSymbol> prov = types.interfaceCandidates(site, (MethodSymbol)m); 2923 if (prov.size() > 1) { 2924 ListBuffer<Symbol> abstracts = new ListBuffer<>(); 2925 ListBuffer<Symbol> defaults = new ListBuffer<>(); 2926 for (MethodSymbol provSym : prov) { 2927 if ((provSym.flags() & DEFAULT) != 0) { 2928 defaults = defaults.append(provSym); 2929 } else if ((provSym.flags() & ABSTRACT) != 0) { 2930 abstracts = abstracts.append(provSym); 2931 } 2932 if (defaults.nonEmpty() && defaults.size() + abstracts.size() >= 2) { 2933 //strong semantics - issue an error if two sibling interfaces 2934 //have two override-equivalent defaults - or if one is abstract 2935 //and the other is default 2936 Fragment diagKey; 2937 Symbol s1 = defaults.first(); 2938 Symbol s2; 2939 if (defaults.size() > 1) { 2940 s2 = defaults.toList().tail.head; 2941 diagKey = Fragments.IncompatibleUnrelatedDefaults(Kinds.kindName(site.tsym), site, 2942 m.name, types.memberType(site, m).getParameterTypes(), 2943 s1.location(), s2.location()); 2944 2945 } else { 2946 s2 = abstracts.first(); 2947 diagKey = Fragments.IncompatibleAbstractDefault(Kinds.kindName(site.tsym), site, 2948 m.name, types.memberType(site, m).getParameterTypes(), 2949 s1.location(), s2.location()); 2950 } 2951 log.error(pos, Errors.TypesIncompatible(s1.location().type, s2.location().type, diagKey)); 2952 break; 2953 } 2954 } 2955 } 2956 } 2957 } 2958 2959 //where 2960 private class DefaultMethodClashFilter implements Predicate<Symbol> { 2961 2962 Type site; 2963 2964 DefaultMethodClashFilter(Type site) { 2965 this.site = site; 2966 } 2967 2968 @Override 2969 public boolean test(Symbol s) { 2970 return s.kind == MTH && 2971 (s.flags() & DEFAULT) != 0 && 2972 s.isInheritedIn(site.tsym, types) && 2973 !s.isInitOrVNew(); 2974 } 2975 } 2976 2977 /** 2978 * Report warnings for potentially ambiguous method declarations. Two declarations 2979 * are potentially ambiguous if they feature two unrelated functional interface 2980 * in same argument position (in which case, a call site passing an implicit 2981 * lambda would be ambiguous). 2982 */ 2983 void checkPotentiallyAmbiguousOverloads(DiagnosticPosition pos, Type site, 2984 MethodSymbol msym1, MethodSymbol msym2) { 2985 if (msym1 != msym2 && 2986 lint.isEnabled(LintCategory.OVERLOADS) && 2987 (msym1.flags() & POTENTIALLY_AMBIGUOUS) == 0 && 2988 (msym2.flags() & POTENTIALLY_AMBIGUOUS) == 0) { 2989 Type mt1 = types.memberType(site, msym1); 2990 Type mt2 = types.memberType(site, msym2); 2991 //if both generic methods, adjust type variables 2992 if (mt1.hasTag(FORALL) && mt2.hasTag(FORALL) && 2993 types.hasSameBounds((ForAll)mt1, (ForAll)mt2)) { 2994 mt2 = types.subst(mt2, ((ForAll)mt2).tvars, ((ForAll)mt1).tvars); 2995 } 2996 //expand varargs methods if needed 2997 int maxLength = Math.max(mt1.getParameterTypes().length(), mt2.getParameterTypes().length()); 2998 List<Type> args1 = rs.adjustArgs(mt1.getParameterTypes(), msym1, maxLength, true); 2999 List<Type> args2 = rs.adjustArgs(mt2.getParameterTypes(), msym2, maxLength, true); 3000 //if arities don't match, exit 3001 if (args1.length() != args2.length()) return; 3002 boolean potentiallyAmbiguous = false; 3003 while (args1.nonEmpty() && args2.nonEmpty()) { 3004 Type s = args1.head; 3005 Type t = args2.head; 3006 if (!types.isSubtype(t, s) && !types.isSubtype(s, t)) { 3007 if (types.isFunctionalInterface(s) && types.isFunctionalInterface(t) && 3008 types.findDescriptorType(s).getParameterTypes().length() > 0 && 3009 types.findDescriptorType(s).getParameterTypes().length() == 3010 types.findDescriptorType(t).getParameterTypes().length()) { 3011 potentiallyAmbiguous = true; 3012 } else { 3013 return; 3014 } 3015 } 3016 args1 = args1.tail; 3017 args2 = args2.tail; 3018 } 3019 if (potentiallyAmbiguous) { 3020 //we found two incompatible functional interfaces with same arity 3021 //this means a call site passing an implicit lambda would be ambiguous 3022 msym1.flags_field |= POTENTIALLY_AMBIGUOUS; 3023 msym2.flags_field |= POTENTIALLY_AMBIGUOUS; 3024 log.warning(LintCategory.OVERLOADS, pos, 3025 Warnings.PotentiallyAmbiguousOverload(msym1, msym1.location(), 3026 msym2, msym2.location())); 3027 return; 3028 } 3029 } 3030 } 3031 3032 void checkAccessFromSerializableElement(final JCTree tree, boolean isLambda) { 3033 if (warnOnAnyAccessToMembers || 3034 (lint.isEnabled(LintCategory.SERIAL) && 3035 !lint.isSuppressed(LintCategory.SERIAL) && 3036 isLambda)) { 3037 Symbol sym = TreeInfo.symbol(tree); 3038 if (!sym.kind.matches(KindSelector.VAL_MTH)) { 3039 return; 3040 } 3041 3042 if (sym.kind == VAR) { 3043 if ((sym.flags() & PARAMETER) != 0 || 3044 sym.isDirectlyOrIndirectlyLocal() || 3045 sym.name == names._this || 3046 sym.name == names._super) { 3047 return; 3048 } 3049 } 3050 3051 if (!types.isSubtype(sym.owner.type, syms.serializableType) && 3052 isEffectivelyNonPublic(sym)) { 3053 if (isLambda) { 3054 if (belongsToRestrictedPackage(sym)) { 3055 log.warning(LintCategory.SERIAL, tree.pos(), 3056 Warnings.AccessToMemberFromSerializableLambda(sym)); 3057 } 3058 } else { 3059 log.warning(tree.pos(), 3060 Warnings.AccessToMemberFromSerializableElement(sym)); 3061 } 3062 } 3063 } 3064 } 3065 3066 private boolean isEffectivelyNonPublic(Symbol sym) { 3067 if (sym.packge() == syms.rootPackage) { 3068 return false; 3069 } 3070 3071 while (sym.kind != PCK) { 3072 if ((sym.flags() & PUBLIC) == 0) { 3073 return true; 3074 } 3075 sym = sym.owner; 3076 } 3077 return false; 3078 } 3079 3080 private boolean belongsToRestrictedPackage(Symbol sym) { 3081 String fullName = sym.packge().fullname.toString(); 3082 return fullName.startsWith("java.") || 3083 fullName.startsWith("javax.") || 3084 fullName.startsWith("sun.") || 3085 fullName.contains(".internal."); 3086 } 3087 3088 /** Check that class c does not implement directly or indirectly 3089 * the same parameterized interface with two different argument lists. 3090 * @param pos Position to be used for error reporting. 3091 * @param type The type whose interfaces are checked. 3092 */ 3093 void checkClassBounds(DiagnosticPosition pos, Type type) { 3094 checkClassBounds(pos, new HashMap<TypeSymbol,Type>(), type); 3095 } 3096 //where 3097 /** Enter all interfaces of type `type' into the hash table `seensofar' 3098 * with their class symbol as key and their type as value. Make 3099 * sure no class is entered with two different types. 3100 */ 3101 void checkClassBounds(DiagnosticPosition pos, 3102 Map<TypeSymbol,Type> seensofar, 3103 Type type) { 3104 if (type.isErroneous()) return; 3105 for (List<Type> l = types.interfaces(type); l.nonEmpty(); l = l.tail) { 3106 Type it = l.head; 3107 if (type.hasTag(CLASS) && !it.hasTag(CLASS)) continue; // JLS 8.1.5 3108 3109 Type oldit = seensofar.put(it.tsym, it); 3110 if (oldit != null) { 3111 List<Type> oldparams = oldit.allparams(); 3112 List<Type> newparams = it.allparams(); 3113 if (!types.containsTypeEquivalent(oldparams, newparams)) 3114 log.error(pos, 3115 Errors.CantInheritDiffArg(it.tsym, 3116 Type.toString(oldparams), 3117 Type.toString(newparams))); 3118 } 3119 checkClassBounds(pos, seensofar, it); 3120 } 3121 Type st = types.supertype(type); 3122 if (type.hasTag(CLASS) && !st.hasTag(CLASS)) return; // JLS 8.1.4 3123 if (st != Type.noType) checkClassBounds(pos, seensofar, st); 3124 } 3125 3126 /** Enter interface into into set. 3127 * If it existed already, issue a "repeated interface" error. 3128 */ 3129 void checkNotRepeated(DiagnosticPosition pos, Type it, Set<Type> its) { 3130 if (its.contains(it)) 3131 log.error(pos, Errors.RepeatedInterface); 3132 else { 3133 its.add(it); 3134 } 3135 } 3136 3137 /* ************************************************************************* 3138 * Check annotations 3139 **************************************************************************/ 3140 3141 /** 3142 * Recursively validate annotations values 3143 */ 3144 void validateAnnotationTree(JCTree tree) { 3145 class AnnotationValidator extends TreeScanner { 3146 @Override 3147 public void visitAnnotation(JCAnnotation tree) { 3148 if (!tree.type.isErroneous() && tree.type.tsym.isAnnotationType()) { 3149 super.visitAnnotation(tree); 3150 validateAnnotation(tree); 3151 } 3152 } 3153 } 3154 tree.accept(new AnnotationValidator()); 3155 } 3156 3157 /** 3158 * {@literal 3159 * Annotation types are restricted to primitives, String, an 3160 * enum, an annotation, Class, Class<?>, Class<? extends 3161 * Anything>, arrays of the preceding. 3162 * } 3163 */ 3164 void validateAnnotationType(JCTree restype) { 3165 // restype may be null if an error occurred, so don't bother validating it 3166 if (restype != null) { 3167 validateAnnotationType(restype.pos(), restype.type); 3168 } 3169 } 3170 3171 void validateAnnotationType(DiagnosticPosition pos, Type type) { 3172 if (type.isPrimitive()) return; 3173 if (types.isSameType(type, syms.stringType)) return; 3174 if ((type.tsym.flags() & Flags.ENUM) != 0) return; 3175 if ((type.tsym.flags() & Flags.ANNOTATION) != 0) return; 3176 if (types.cvarLowerBound(type).tsym == syms.classType.tsym) return; 3177 if (types.isArray(type) && !types.isArray(types.elemtype(type))) { 3178 validateAnnotationType(pos, types.elemtype(type)); 3179 return; 3180 } 3181 log.error(pos, Errors.InvalidAnnotationMemberType); 3182 } 3183 3184 /** 3185 * "It is also a compile-time error if any method declared in an 3186 * annotation type has a signature that is override-equivalent to 3187 * that of any public or protected method declared in class Object 3188 * or in the interface annotation.Annotation." 3189 * 3190 * @jls 9.6 Annotation Types 3191 */ 3192 void validateAnnotationMethod(DiagnosticPosition pos, MethodSymbol m) { 3193 for (Type sup = syms.annotationType; sup.hasTag(CLASS); sup = types.supertype(sup)) { 3194 Scope s = sup.tsym.members(); 3195 for (Symbol sym : s.getSymbolsByName(m.name)) { 3196 if (sym.kind == MTH && 3197 (sym.flags() & (PUBLIC | PROTECTED)) != 0 && 3198 types.overrideEquivalent(m.type, sym.type)) 3199 log.error(pos, Errors.IntfAnnotationMemberClash(sym, sup)); 3200 } 3201 } 3202 } 3203 3204 /** Check the annotations of a symbol. 3205 */ 3206 public void validateAnnotations(List<JCAnnotation> annotations, JCTree declarationTree, Symbol s) { 3207 for (JCAnnotation a : annotations) 3208 validateAnnotation(a, declarationTree, s); 3209 } 3210 3211 /** Check the type annotations. 3212 */ 3213 public void validateTypeAnnotations(List<JCAnnotation> annotations, boolean isTypeParameter) { 3214 for (JCAnnotation a : annotations) 3215 validateTypeAnnotation(a, isTypeParameter); 3216 } 3217 3218 /** Check an annotation of a symbol. 3219 */ 3220 private void validateAnnotation(JCAnnotation a, JCTree declarationTree, Symbol s) { 3221 /** NOTE: if annotation processors are present, annotation processing rounds can happen after this method, 3222 * this can impact in particular records for which annotations are forcibly propagated. 3223 */ 3224 validateAnnotationTree(a); 3225 boolean isRecordMember = ((s.flags_field & RECORD) != 0 || s.enclClass() != null && s.enclClass().isRecord()); 3226 3227 boolean isRecordField = (s.flags_field & RECORD) != 0 && 3228 declarationTree.hasTag(VARDEF) && 3229 s.owner.kind == TYP; 3230 3231 if (isRecordField) { 3232 // first we need to check if the annotation is applicable to records 3233 Name[] targets = getTargetNames(a); 3234 boolean appliesToRecords = false; 3235 for (Name target : targets) { 3236 appliesToRecords = 3237 target == names.FIELD || 3238 target == names.PARAMETER || 3239 target == names.METHOD || 3240 target == names.TYPE_USE || 3241 target == names.RECORD_COMPONENT; 3242 if (appliesToRecords) { 3243 break; 3244 } 3245 } 3246 if (!appliesToRecords) { 3247 log.error(a.pos(), Errors.AnnotationTypeNotApplicable); 3248 } else { 3249 /* lets now find the annotations in the field that are targeted to record components and append them to 3250 * the corresponding record component 3251 */ 3252 ClassSymbol recordClass = (ClassSymbol) s.owner; 3253 RecordComponent rc = recordClass.getRecordComponent((VarSymbol)s); 3254 SymbolMetadata metadata = rc.getMetadata(); 3255 if (metadata == null || metadata.isEmpty()) { 3256 /* if not is empty then we have already been here, which is the case if multiple annotations are applied 3257 * to the record component declaration 3258 */ 3259 rc.appendAttributes(s.getRawAttributes().stream().filter(anno -> 3260 Arrays.stream(getTargetNames(anno.type.tsym)).anyMatch(name -> name == names.RECORD_COMPONENT) 3261 ).collect(List.collector())); 3262 3263 JCVariableDecl fieldAST = (JCVariableDecl) declarationTree; 3264 for (JCAnnotation fieldAnnot : fieldAST.mods.annotations) { 3265 for (JCAnnotation rcAnnot : rc.declarationFor().mods.annotations) { 3266 if (rcAnnot.pos == fieldAnnot.pos) { 3267 rcAnnot.setType(fieldAnnot.type); 3268 break; 3269 } 3270 } 3271 } 3272 3273 /* At this point, we used to carry over any type annotations from the VARDEF to the record component, but 3274 * that is problematic, since we get here only when *some* annotation is applied to the SE5 (declaration) 3275 * annotation location, inadvertently failing to carry over the type annotations when the VarDef has no 3276 * annotations in the SE5 annotation location. 3277 * 3278 * Now type annotations are assigned to record components in a method that would execute irrespective of 3279 * whether there are SE5 annotations on a VarDef viz com.sun.tools.javac.code.TypeAnnotations.TypeAnnotationPositions.visitVarDef 3280 */ 3281 } 3282 } 3283 } 3284 3285 /* the section below is tricky. Annotations applied to record components are propagated to the corresponding 3286 * record member so if an annotation has target: FIELD, it is propagated to the corresponding FIELD, if it has 3287 * target METHOD, it is propagated to the accessor and so on. But at the moment when method members are generated 3288 * there is no enough information to propagate only the right annotations. So all the annotations are propagated 3289 * to all the possible locations. 3290 * 3291 * At this point we need to remove all the annotations that are not in place before going on with the annotation 3292 * party. On top of the above there is the issue that there is no AST representing record components, just symbols 3293 * so the corresponding field has been holding all the annotations and it's metadata has been modified as if it 3294 * was both a field and a record component. 3295 * 3296 * So there are two places where we need to trim annotations from: the metadata of the symbol and / or the modifiers 3297 * in the AST. Whatever is in the metadata will be written to the class file, whatever is in the modifiers could 3298 * be see by annotation processors. 3299 * 3300 * The metadata contains both type annotations and declaration annotations. At this point of the game we don't 3301 * need to care about type annotations, they are all in the right place. But we could need to remove declaration 3302 * annotations. So for declaration annotations if they are not applicable to the record member, excluding type 3303 * annotations which are already correct, then we will remove it. For the AST modifiers if the annotation is not 3304 * applicable either as type annotation and or declaration annotation, only in that case it will be removed. 3305 * 3306 * So it could be that annotation is removed as a declaration annotation but it is kept in the AST modifier for 3307 * further inspection by annotation processors. 3308 * 3309 * For example: 3310 * 3311 * import java.lang.annotation.*; 3312 * 3313 * @Target({ElementType.TYPE_USE, ElementType.RECORD_COMPONENT}) 3314 * @Retention(RetentionPolicy.RUNTIME) 3315 * @interface Anno { } 3316 * 3317 * record R(@Anno String s) {} 3318 * 3319 * at this point we will have for the case of the generated field: 3320 * - @Anno in the modifier 3321 * - @Anno as a type annotation 3322 * - @Anno as a declaration annotation 3323 * 3324 * the last one should be removed because the annotation has not FIELD as target but it was applied as a 3325 * declaration annotation because the field was being treated both as a field and as a record component 3326 * as we have already copied the annotations to the record component, now the field doesn't need to hold 3327 * annotations that are not intended for it anymore. Still @Anno has to be kept in the AST's modifiers as it 3328 * is applicable as a type annotation to the type of the field. 3329 */ 3330 3331 if (a.type.tsym.isAnnotationType()) { 3332 Optional<Set<Name>> applicableTargetsOp = getApplicableTargets(a, s); 3333 if (!applicableTargetsOp.isEmpty()) { 3334 Set<Name> applicableTargets = applicableTargetsOp.get(); 3335 boolean notApplicableOrIsTypeUseOnly = applicableTargets.isEmpty() || 3336 applicableTargets.size() == 1 && applicableTargets.contains(names.TYPE_USE); 3337 boolean isCompGeneratedRecordElement = isRecordMember && (s.flags_field & Flags.GENERATED_MEMBER) != 0; 3338 boolean isCompRecordElementWithNonApplicableDeclAnno = isCompGeneratedRecordElement && notApplicableOrIsTypeUseOnly; 3339 3340 if (applicableTargets.isEmpty() || isCompRecordElementWithNonApplicableDeclAnno) { 3341 if (isCompRecordElementWithNonApplicableDeclAnno) { 3342 /* so we have found an annotation that is not applicable to a record member that was generated by the 3343 * compiler. This was intentionally done at TypeEnter, now is the moment strip away the annotations 3344 * that are not applicable to the given record member 3345 */ 3346 JCModifiers modifiers = TreeInfo.getModifiers(declarationTree); 3347 /* lets first remove the annotation from the modifier if it is not applicable, we have to check again as 3348 * it could be a type annotation 3349 */ 3350 if (modifiers != null && applicableTargets.isEmpty()) { 3351 ListBuffer<JCAnnotation> newAnnotations = new ListBuffer<>(); 3352 for (JCAnnotation anno : modifiers.annotations) { 3353 if (anno != a) { 3354 newAnnotations.add(anno); 3355 } 3356 } 3357 modifiers.annotations = newAnnotations.toList(); 3358 } 3359 // now lets remove it from the symbol 3360 s.getMetadata().removeDeclarationMetadata(a.attribute); 3361 } else { 3362 log.error(a.pos(), Errors.AnnotationTypeNotApplicable); 3363 } 3364 } 3365 /* if we are seeing the @SafeVarargs annotation applied to a compiler generated accessor, 3366 * then this is an error as we know that no compiler generated accessor will be a varargs 3367 * method, better to fail asap 3368 */ 3369 if (isCompGeneratedRecordElement && !isRecordField && a.type.tsym == syms.trustMeType.tsym && declarationTree.hasTag(METHODDEF)) { 3370 log.error(a.pos(), Errors.VarargsInvalidTrustmeAnno(syms.trustMeType.tsym, Fragments.VarargsTrustmeOnNonVarargsAccessor(s))); 3371 } 3372 } 3373 } 3374 3375 if (a.annotationType.type.tsym == syms.functionalInterfaceType.tsym) { 3376 if (s.kind != TYP) { 3377 log.error(a.pos(), Errors.BadFunctionalIntfAnno); 3378 } else if (!s.isInterface() || (s.flags() & ANNOTATION) != 0) { 3379 log.error(a.pos(), Errors.BadFunctionalIntfAnno1(Fragments.NotAFunctionalIntf(s))); 3380 } 3381 } 3382 } 3383 3384 public void validateTypeAnnotation(JCAnnotation a, boolean isTypeParameter) { 3385 Assert.checkNonNull(a.type); 3386 validateAnnotationTree(a); 3387 3388 if (a.hasTag(TYPE_ANNOTATION) && 3389 !a.annotationType.type.isErroneous() && 3390 !isTypeAnnotation(a, isTypeParameter)) { 3391 log.error(a.pos(), Errors.AnnotationTypeNotApplicableToType(a.type)); 3392 } 3393 } 3394 3395 /** 3396 * Validate the proposed container 'repeatable' on the 3397 * annotation type symbol 's'. Report errors at position 3398 * 'pos'. 3399 * 3400 * @param s The (annotation)type declaration annotated with a @Repeatable 3401 * @param repeatable the @Repeatable on 's' 3402 * @param pos where to report errors 3403 */ 3404 public void validateRepeatable(TypeSymbol s, Attribute.Compound repeatable, DiagnosticPosition pos) { 3405 Assert.check(types.isSameType(repeatable.type, syms.repeatableType)); 3406 3407 Type t = null; 3408 List<Pair<MethodSymbol,Attribute>> l = repeatable.values; 3409 if (!l.isEmpty()) { 3410 Assert.check(l.head.fst.name == names.value); 3411 if (l.head.snd instanceof Attribute.Class) { 3412 t = ((Attribute.Class)l.head.snd).getValue(); 3413 } 3414 } 3415 3416 if (t == null) { 3417 // errors should already have been reported during Annotate 3418 return; 3419 } 3420 3421 validateValue(t.tsym, s, pos); 3422 validateRetention(t.tsym, s, pos); 3423 validateDocumented(t.tsym, s, pos); 3424 validateInherited(t.tsym, s, pos); 3425 validateTarget(t.tsym, s, pos); 3426 validateDefault(t.tsym, pos); 3427 } 3428 3429 private void validateValue(TypeSymbol container, TypeSymbol contained, DiagnosticPosition pos) { 3430 Symbol sym = container.members().findFirst(names.value); 3431 if (sym != null && sym.kind == MTH) { 3432 MethodSymbol m = (MethodSymbol) sym; 3433 Type ret = m.getReturnType(); 3434 if (!(ret.hasTag(ARRAY) && types.isSameType(((ArrayType)ret).elemtype, contained.type))) { 3435 log.error(pos, 3436 Errors.InvalidRepeatableAnnotationValueReturn(container, 3437 ret, 3438 types.makeArrayType(contained.type))); 3439 } 3440 } else { 3441 log.error(pos, Errors.InvalidRepeatableAnnotationNoValue(container)); 3442 } 3443 } 3444 3445 private void validateRetention(TypeSymbol container, TypeSymbol contained, DiagnosticPosition pos) { 3446 Attribute.RetentionPolicy containerRetention = types.getRetention(container); 3447 Attribute.RetentionPolicy containedRetention = types.getRetention(contained); 3448 3449 boolean error = false; 3450 switch (containedRetention) { 3451 case RUNTIME: 3452 if (containerRetention != Attribute.RetentionPolicy.RUNTIME) { 3453 error = true; 3454 } 3455 break; 3456 case CLASS: 3457 if (containerRetention == Attribute.RetentionPolicy.SOURCE) { 3458 error = true; 3459 } 3460 } 3461 if (error ) { 3462 log.error(pos, 3463 Errors.InvalidRepeatableAnnotationRetention(container, 3464 containerRetention.name(), 3465 contained, 3466 containedRetention.name())); 3467 } 3468 } 3469 3470 private void validateDocumented(Symbol container, Symbol contained, DiagnosticPosition pos) { 3471 if (contained.attribute(syms.documentedType.tsym) != null) { 3472 if (container.attribute(syms.documentedType.tsym) == null) { 3473 log.error(pos, Errors.InvalidRepeatableAnnotationNotDocumented(container, contained)); 3474 } 3475 } 3476 } 3477 3478 private void validateInherited(Symbol container, Symbol contained, DiagnosticPosition pos) { 3479 if (contained.attribute(syms.inheritedType.tsym) != null) { 3480 if (container.attribute(syms.inheritedType.tsym) == null) { 3481 log.error(pos, Errors.InvalidRepeatableAnnotationNotInherited(container, contained)); 3482 } 3483 } 3484 } 3485 3486 private void validateTarget(TypeSymbol container, TypeSymbol contained, DiagnosticPosition pos) { 3487 // The set of targets the container is applicable to must be a subset 3488 // (with respect to annotation target semantics) of the set of targets 3489 // the contained is applicable to. The target sets may be implicit or 3490 // explicit. 3491 3492 Set<Name> containerTargets; 3493 Attribute.Array containerTarget = getAttributeTargetAttribute(container); 3494 if (containerTarget == null) { 3495 containerTargets = getDefaultTargetSet(); 3496 } else { 3497 containerTargets = new HashSet<>(); 3498 for (Attribute app : containerTarget.values) { 3499 if (!(app instanceof Attribute.Enum attributeEnum)) { 3500 continue; // recovery 3501 } 3502 containerTargets.add(attributeEnum.value.name); 3503 } 3504 } 3505 3506 Set<Name> containedTargets; 3507 Attribute.Array containedTarget = getAttributeTargetAttribute(contained); 3508 if (containedTarget == null) { 3509 containedTargets = getDefaultTargetSet(); 3510 } else { 3511 containedTargets = new HashSet<>(); 3512 for (Attribute app : containedTarget.values) { 3513 if (!(app instanceof Attribute.Enum attributeEnum)) { 3514 continue; // recovery 3515 } 3516 containedTargets.add(attributeEnum.value.name); 3517 } 3518 } 3519 3520 if (!isTargetSubsetOf(containerTargets, containedTargets)) { 3521 log.error(pos, Errors.InvalidRepeatableAnnotationIncompatibleTarget(container, contained)); 3522 } 3523 } 3524 3525 /* get a set of names for the default target */ 3526 private Set<Name> getDefaultTargetSet() { 3527 if (defaultTargets == null) { 3528 defaultTargets = Set.of(defaultTargetMetaInfo()); 3529 } 3530 3531 return defaultTargets; 3532 } 3533 private Set<Name> defaultTargets; 3534 3535 3536 /** Checks that s is a subset of t, with respect to ElementType 3537 * semantics, specifically {ANNOTATION_TYPE} is a subset of {TYPE}, 3538 * and {TYPE_USE} covers the set {ANNOTATION_TYPE, TYPE, TYPE_USE, 3539 * TYPE_PARAMETER}. 3540 */ 3541 private boolean isTargetSubsetOf(Set<Name> s, Set<Name> t) { 3542 // Check that all elements in s are present in t 3543 for (Name n2 : s) { 3544 boolean currentElementOk = false; 3545 for (Name n1 : t) { 3546 if (n1 == n2) { 3547 currentElementOk = true; 3548 break; 3549 } else if (n1 == names.TYPE && n2 == names.ANNOTATION_TYPE) { 3550 currentElementOk = true; 3551 break; 3552 } else if (n1 == names.TYPE_USE && 3553 (n2 == names.TYPE || 3554 n2 == names.ANNOTATION_TYPE || 3555 n2 == names.TYPE_PARAMETER)) { 3556 currentElementOk = true; 3557 break; 3558 } 3559 } 3560 if (!currentElementOk) 3561 return false; 3562 } 3563 return true; 3564 } 3565 3566 private void validateDefault(Symbol container, DiagnosticPosition pos) { 3567 // validate that all other elements of containing type has defaults 3568 Scope scope = container.members(); 3569 for(Symbol elm : scope.getSymbols()) { 3570 if (elm.name != names.value && 3571 elm.kind == MTH && 3572 ((MethodSymbol)elm).defaultValue == null) { 3573 log.error(pos, 3574 Errors.InvalidRepeatableAnnotationElemNondefault(container, elm)); 3575 } 3576 } 3577 } 3578 3579 /** Is s a method symbol that overrides a method in a superclass? */ 3580 boolean isOverrider(Symbol s) { 3581 if (s.kind != MTH || s.isStatic()) 3582 return false; 3583 MethodSymbol m = (MethodSymbol)s; 3584 TypeSymbol owner = (TypeSymbol)m.owner; 3585 for (Type sup : types.closure(owner.type)) { 3586 if (sup == owner.type) 3587 continue; // skip "this" 3588 Scope scope = sup.tsym.members(); 3589 for (Symbol sym : scope.getSymbolsByName(m.name)) { 3590 if (!sym.isStatic() && m.overrides(sym, owner, types, true)) 3591 return true; 3592 } 3593 } 3594 return false; 3595 } 3596 3597 /** Is the annotation applicable to types? */ 3598 protected boolean isTypeAnnotation(JCAnnotation a, boolean isTypeParameter) { 3599 List<Attribute> targets = typeAnnotations.annotationTargets(a.annotationType.type.tsym); 3600 return (targets == null) ? 3601 false : 3602 targets.stream() 3603 .anyMatch(attr -> isTypeAnnotation(attr, isTypeParameter)); 3604 } 3605 //where 3606 boolean isTypeAnnotation(Attribute a, boolean isTypeParameter) { 3607 Attribute.Enum e = (Attribute.Enum)a; 3608 return (e.value.name == names.TYPE_USE || 3609 (isTypeParameter && e.value.name == names.TYPE_PARAMETER)); 3610 } 3611 3612 /** Is the annotation applicable to the symbol? */ 3613 Name[] getTargetNames(JCAnnotation a) { 3614 return getTargetNames(a.annotationType.type.tsym); 3615 } 3616 3617 public Name[] getTargetNames(TypeSymbol annoSym) { 3618 Attribute.Array arr = getAttributeTargetAttribute(annoSym); 3619 Name[] targets; 3620 if (arr == null) { 3621 targets = defaultTargetMetaInfo(); 3622 } else { 3623 // TODO: can we optimize this? 3624 targets = new Name[arr.values.length]; 3625 for (int i=0; i<arr.values.length; ++i) { 3626 Attribute app = arr.values[i]; 3627 if (!(app instanceof Attribute.Enum attributeEnum)) { 3628 return new Name[0]; 3629 } 3630 targets[i] = attributeEnum.value.name; 3631 } 3632 } 3633 return targets; 3634 } 3635 3636 boolean annotationApplicable(JCAnnotation a, Symbol s) { 3637 Optional<Set<Name>> targets = getApplicableTargets(a, s); 3638 /* the optional could be empty if the annotation is unknown in that case 3639 * we return that it is applicable and if it is erroneous that should imply 3640 * an error at the declaration site 3641 */ 3642 return targets.isEmpty() || targets.isPresent() && !targets.get().isEmpty(); 3643 } 3644 3645 Optional<Set<Name>> getApplicableTargets(JCAnnotation a, Symbol s) { 3646 Attribute.Array arr = getAttributeTargetAttribute(a.annotationType.type.tsym); 3647 Name[] targets; 3648 Set<Name> applicableTargets = new HashSet<>(); 3649 3650 if (arr == null) { 3651 targets = defaultTargetMetaInfo(); 3652 } else { 3653 // TODO: can we optimize this? 3654 targets = new Name[arr.values.length]; 3655 for (int i=0; i<arr.values.length; ++i) { 3656 Attribute app = arr.values[i]; 3657 if (!(app instanceof Attribute.Enum attributeEnum)) { 3658 // recovery 3659 return Optional.empty(); 3660 } 3661 targets[i] = attributeEnum.value.name; 3662 } 3663 } 3664 for (Name target : targets) { 3665 if (target == names.TYPE) { 3666 if (s.kind == TYP) 3667 applicableTargets.add(names.TYPE); 3668 } else if (target == names.FIELD) { 3669 if (s.kind == VAR && s.owner.kind != MTH) 3670 applicableTargets.add(names.FIELD); 3671 } else if (target == names.RECORD_COMPONENT) { 3672 if (s.getKind() == ElementKind.RECORD_COMPONENT) { 3673 applicableTargets.add(names.RECORD_COMPONENT); 3674 } 3675 } else if (target == names.METHOD) { 3676 if (s.kind == MTH && !s.isInitOrVNew()) 3677 applicableTargets.add(names.METHOD); 3678 } else if (target == names.PARAMETER) { 3679 if (s.kind == VAR && 3680 (s.owner.kind == MTH && (s.flags() & PARAMETER) != 0)) { 3681 applicableTargets.add(names.PARAMETER); 3682 } 3683 } else if (target == names.CONSTRUCTOR) { 3684 if (s.kind == MTH && s.isInitOrVNew()) 3685 applicableTargets.add(names.CONSTRUCTOR); 3686 } else if (target == names.LOCAL_VARIABLE) { 3687 if (s.kind == VAR && s.owner.kind == MTH && 3688 (s.flags() & PARAMETER) == 0) { 3689 applicableTargets.add(names.LOCAL_VARIABLE); 3690 } 3691 } else if (target == names.ANNOTATION_TYPE) { 3692 if (s.kind == TYP && (s.flags() & ANNOTATION) != 0) { 3693 applicableTargets.add(names.ANNOTATION_TYPE); 3694 } 3695 } else if (target == names.PACKAGE) { 3696 if (s.kind == PCK) 3697 applicableTargets.add(names.PACKAGE); 3698 } else if (target == names.TYPE_USE) { 3699 if (s.kind == VAR && s.owner.kind == MTH && s.type.hasTag(NONE)) { 3700 //cannot type annotate implicitly typed locals 3701 continue; 3702 } else if (s.kind == TYP || s.kind == VAR || 3703 (s.kind == MTH && !s.isInitOrVNew() && 3704 !s.type.getReturnType().hasTag(VOID)) || 3705 (s.kind == MTH && s.isInitOrVNew())) { 3706 applicableTargets.add(names.TYPE_USE); 3707 } 3708 } else if (target == names.TYPE_PARAMETER) { 3709 if (s.kind == TYP && s.type.hasTag(TYPEVAR)) 3710 applicableTargets.add(names.TYPE_PARAMETER); 3711 } else if (target == names.MODULE) { 3712 if (s.kind == MDL) 3713 applicableTargets.add(names.MODULE); 3714 } else 3715 return Optional.empty(); // Unknown ElementType. This should be an error at declaration site, 3716 // assume applicable. 3717 } 3718 return Optional.of(applicableTargets); 3719 } 3720 3721 Attribute.Array getAttributeTargetAttribute(TypeSymbol s) { 3722 Attribute.Compound atTarget = s.getAnnotationTypeMetadata().getTarget(); 3723 if (atTarget == null) return null; // ok, is applicable 3724 Attribute atValue = atTarget.member(names.value); 3725 return (atValue instanceof Attribute.Array attributeArray) ? attributeArray : null; 3726 } 3727 3728 private Name[] dfltTargetMeta; 3729 private Name[] defaultTargetMetaInfo() { 3730 if (dfltTargetMeta == null) { 3731 ArrayList<Name> defaultTargets = new ArrayList<>(); 3732 defaultTargets.add(names.PACKAGE); 3733 defaultTargets.add(names.TYPE); 3734 defaultTargets.add(names.FIELD); 3735 defaultTargets.add(names.METHOD); 3736 defaultTargets.add(names.CONSTRUCTOR); 3737 defaultTargets.add(names.ANNOTATION_TYPE); 3738 defaultTargets.add(names.LOCAL_VARIABLE); 3739 defaultTargets.add(names.PARAMETER); 3740 if (allowRecords) { 3741 defaultTargets.add(names.RECORD_COMPONENT); 3742 } 3743 if (allowModules) { 3744 defaultTargets.add(names.MODULE); 3745 } 3746 dfltTargetMeta = defaultTargets.toArray(new Name[0]); 3747 } 3748 return dfltTargetMeta; 3749 } 3750 3751 /** Check an annotation value. 3752 * 3753 * @param a The annotation tree to check 3754 * @return true if this annotation tree is valid, otherwise false 3755 */ 3756 public boolean validateAnnotationDeferErrors(JCAnnotation a) { 3757 boolean res = false; 3758 final Log.DiagnosticHandler diagHandler = new Log.DiscardDiagnosticHandler(log); 3759 try { 3760 res = validateAnnotation(a); 3761 } finally { 3762 log.popDiagnosticHandler(diagHandler); 3763 } 3764 return res; 3765 } 3766 3767 private boolean validateAnnotation(JCAnnotation a) { 3768 boolean isValid = true; 3769 AnnotationTypeMetadata metadata = a.annotationType.type.tsym.getAnnotationTypeMetadata(); 3770 3771 // collect an inventory of the annotation elements 3772 Set<MethodSymbol> elements = metadata.getAnnotationElements(); 3773 3774 // remove the ones that are assigned values 3775 for (JCTree arg : a.args) { 3776 if (!arg.hasTag(ASSIGN)) continue; // recovery 3777 JCAssign assign = (JCAssign)arg; 3778 Symbol m = TreeInfo.symbol(assign.lhs); 3779 if (m == null || m.type.isErroneous()) continue; 3780 if (!elements.remove(m)) { 3781 isValid = false; 3782 log.error(assign.lhs.pos(), 3783 Errors.DuplicateAnnotationMemberValue(m.name, a.type)); 3784 } 3785 } 3786 3787 // all the remaining ones better have default values 3788 List<Name> missingDefaults = List.nil(); 3789 Set<MethodSymbol> membersWithDefault = metadata.getAnnotationElementsWithDefault(); 3790 for (MethodSymbol m : elements) { 3791 if (m.type.isErroneous()) 3792 continue; 3793 3794 if (!membersWithDefault.contains(m)) 3795 missingDefaults = missingDefaults.append(m.name); 3796 } 3797 missingDefaults = missingDefaults.reverse(); 3798 if (missingDefaults.nonEmpty()) { 3799 isValid = false; 3800 Error errorKey = (missingDefaults.size() > 1) 3801 ? Errors.AnnotationMissingDefaultValue1(a.type, missingDefaults) 3802 : Errors.AnnotationMissingDefaultValue(a.type, missingDefaults); 3803 log.error(a.pos(), errorKey); 3804 } 3805 3806 return isValid && validateTargetAnnotationValue(a); 3807 } 3808 3809 /* Validate the special java.lang.annotation.Target annotation */ 3810 boolean validateTargetAnnotationValue(JCAnnotation a) { 3811 // special case: java.lang.annotation.Target must not have 3812 // repeated values in its value member 3813 if (a.annotationType.type.tsym != syms.annotationTargetType.tsym || 3814 a.args.tail == null) 3815 return true; 3816 3817 boolean isValid = true; 3818 if (!a.args.head.hasTag(ASSIGN)) return false; // error recovery 3819 JCAssign assign = (JCAssign) a.args.head; 3820 Symbol m = TreeInfo.symbol(assign.lhs); 3821 if (m.name != names.value) return false; 3822 JCTree rhs = assign.rhs; 3823 if (!rhs.hasTag(NEWARRAY)) return false; 3824 JCNewArray na = (JCNewArray) rhs; 3825 Set<Symbol> targets = new HashSet<>(); 3826 for (JCTree elem : na.elems) { 3827 if (!targets.add(TreeInfo.symbol(elem))) { 3828 isValid = false; 3829 log.error(elem.pos(), Errors.RepeatedAnnotationTarget); 3830 } 3831 } 3832 return isValid; 3833 } 3834 3835 void checkDeprecatedAnnotation(DiagnosticPosition pos, Symbol s) { 3836 if (lint.isEnabled(LintCategory.DEP_ANN) && s.isDeprecatableViaAnnotation() && 3837 (s.flags() & DEPRECATED) != 0 && 3838 !syms.deprecatedType.isErroneous() && 3839 s.attribute(syms.deprecatedType.tsym) == null) { 3840 log.warning(LintCategory.DEP_ANN, 3841 pos, Warnings.MissingDeprecatedAnnotation); 3842 } 3843 // Note: @Deprecated has no effect on local variables, parameters and package decls. 3844 if (lint.isEnabled(LintCategory.DEPRECATION) && !s.isDeprecatableViaAnnotation()) { 3845 if (!syms.deprecatedType.isErroneous() && s.attribute(syms.deprecatedType.tsym) != null) { 3846 log.warning(LintCategory.DEPRECATION, pos, 3847 Warnings.DeprecatedAnnotationHasNoEffect(Kinds.kindName(s))); 3848 } 3849 } 3850 } 3851 3852 void checkDeprecated(final DiagnosticPosition pos, final Symbol other, final Symbol s) { 3853 checkDeprecated(() -> pos, other, s); 3854 } 3855 3856 void checkDeprecated(Supplier<DiagnosticPosition> pos, final Symbol other, final Symbol s) { 3857 if ( (s.isDeprecatedForRemoval() 3858 || s.isDeprecated() && !other.isDeprecated()) 3859 && (s.outermostClass() != other.outermostClass() || s.outermostClass() == null) 3860 && s.kind != Kind.PCK) { 3861 deferredLintHandler.report(() -> warnDeprecated(pos.get(), s)); 3862 } 3863 } 3864 3865 void checkSunAPI(final DiagnosticPosition pos, final Symbol s) { 3866 if ((s.flags() & PROPRIETARY) != 0) { 3867 deferredLintHandler.report(() -> { 3868 log.mandatoryWarning(pos, Warnings.SunProprietary(s)); 3869 }); 3870 } 3871 } 3872 3873 void checkProfile(final DiagnosticPosition pos, final Symbol s) { 3874 if (profile != Profile.DEFAULT && (s.flags() & NOT_IN_PROFILE) != 0) { 3875 log.error(pos, Errors.NotInProfile(s, profile)); 3876 } 3877 } 3878 3879 void checkPreview(DiagnosticPosition pos, Symbol other, Symbol s) { 3880 if ((s.flags() & PREVIEW_API) != 0 && !preview.participatesInPreview(syms, other, s)) { 3881 if ((s.flags() & PREVIEW_REFLECTIVE) == 0) { 3882 if (!preview.isEnabled()) { 3883 log.error(pos, Errors.IsPreview(s)); 3884 } else { 3885 preview.markUsesPreview(pos); 3886 deferredLintHandler.report(() -> warnPreviewAPI(pos, Warnings.IsPreview(s))); 3887 } 3888 } else { 3889 deferredLintHandler.report(() -> warnPreviewAPI(pos, Warnings.IsPreviewReflective(s))); 3890 } 3891 } 3892 if (preview.declaredUsingPreviewFeature(s)) { 3893 if (preview.isEnabled()) { 3894 //for preview disabled do presumably so not need to do anything? 3895 //If "s" is compiled from source, then there was an error for it already; 3896 //if "s" is from classfile, there already was an error for the classfile. 3897 preview.markUsesPreview(pos); 3898 deferredLintHandler.report(() -> warnDeclaredUsingPreview(pos, s)); 3899 } 3900 } 3901 } 3902 3903 /* ************************************************************************* 3904 * Check for recursive annotation elements. 3905 **************************************************************************/ 3906 3907 /** Check for cycles in the graph of annotation elements. 3908 */ 3909 void checkNonCyclicElements(JCClassDecl tree) { 3910 if ((tree.sym.flags_field & ANNOTATION) == 0) return; 3911 Assert.check((tree.sym.flags_field & LOCKED) == 0); 3912 try { 3913 tree.sym.flags_field |= LOCKED; 3914 for (JCTree def : tree.defs) { 3915 if (!def.hasTag(METHODDEF)) continue; 3916 JCMethodDecl meth = (JCMethodDecl)def; 3917 checkAnnotationResType(meth.pos(), meth.restype.type); 3918 } 3919 } finally { 3920 tree.sym.flags_field &= ~LOCKED; 3921 tree.sym.flags_field |= ACYCLIC_ANN; 3922 } 3923 } 3924 3925 void checkNonCyclicElementsInternal(DiagnosticPosition pos, TypeSymbol tsym) { 3926 if ((tsym.flags_field & ACYCLIC_ANN) != 0) 3927 return; 3928 if ((tsym.flags_field & LOCKED) != 0) { 3929 log.error(pos, Errors.CyclicAnnotationElement(tsym)); 3930 return; 3931 } 3932 try { 3933 tsym.flags_field |= LOCKED; 3934 for (Symbol s : tsym.members().getSymbols(NON_RECURSIVE)) { 3935 if (s.kind != MTH) 3936 continue; 3937 checkAnnotationResType(pos, ((MethodSymbol)s).type.getReturnType()); 3938 } 3939 } finally { 3940 tsym.flags_field &= ~LOCKED; 3941 tsym.flags_field |= ACYCLIC_ANN; 3942 } 3943 } 3944 3945 void checkAnnotationResType(DiagnosticPosition pos, Type type) { 3946 switch (type.getTag()) { 3947 case CLASS: 3948 if ((type.tsym.flags() & ANNOTATION) != 0) 3949 checkNonCyclicElementsInternal(pos, type.tsym); 3950 break; 3951 case ARRAY: 3952 checkAnnotationResType(pos, types.elemtype(type)); 3953 break; 3954 default: 3955 break; // int etc 3956 } 3957 } 3958 3959 /* ************************************************************************* 3960 * Check for cycles in the constructor call graph. 3961 **************************************************************************/ 3962 3963 /** Check for cycles in the graph of constructors calling other 3964 * constructors. 3965 */ 3966 void checkCyclicConstructors(JCClassDecl tree) { 3967 // use LinkedHashMap so we generate errors deterministically 3968 Map<Symbol,Symbol> callMap = new LinkedHashMap<>(); 3969 3970 // enter each constructor this-call into the map 3971 for (List<JCTree> l = tree.defs; l.nonEmpty(); l = l.tail) { 3972 JCMethodInvocation app = TreeInfo.firstConstructorCall(l.head); 3973 if (app == null) continue; 3974 JCMethodDecl meth = (JCMethodDecl) l.head; 3975 if (TreeInfo.name(app.meth) == names._this) { 3976 callMap.put(meth.sym, TreeInfo.symbol(app.meth)); 3977 } else { 3978 meth.sym.flags_field |= ACYCLIC; 3979 } 3980 } 3981 3982 // Check for cycles in the map 3983 Symbol[] ctors = new Symbol[0]; 3984 ctors = callMap.keySet().toArray(ctors); 3985 for (Symbol caller : ctors) { 3986 checkCyclicConstructor(tree, caller, callMap); 3987 } 3988 } 3989 3990 /** Look in the map to see if the given constructor is part of a 3991 * call cycle. 3992 */ 3993 private void checkCyclicConstructor(JCClassDecl tree, Symbol ctor, 3994 Map<Symbol,Symbol> callMap) { 3995 if (ctor != null && (ctor.flags_field & ACYCLIC) == 0) { 3996 if ((ctor.flags_field & LOCKED) != 0) { 3997 log.error(TreeInfo.diagnosticPositionFor(ctor, tree, false, t -> t.hasTag(IDENT)), 3998 Errors.RecursiveCtorInvocation); 3999 } else { 4000 ctor.flags_field |= LOCKED; 4001 checkCyclicConstructor(tree, callMap.remove(ctor), callMap); 4002 ctor.flags_field &= ~LOCKED; 4003 } 4004 ctor.flags_field |= ACYCLIC; 4005 } 4006 } 4007 4008 /* ************************************************************************* 4009 * Miscellaneous 4010 **************************************************************************/ 4011 4012 /** 4013 * Check for division by integer constant zero 4014 * @param pos Position for error reporting. 4015 * @param operator The operator for the expression 4016 * @param operand The right hand operand for the expression 4017 */ 4018 void checkDivZero(final DiagnosticPosition pos, Symbol operator, Type operand) { 4019 if (operand.constValue() != null 4020 && operand.getTag().isSubRangeOf(LONG) 4021 && ((Number) (operand.constValue())).longValue() == 0) { 4022 int opc = ((OperatorSymbol)operator).opcode; 4023 if (opc == ByteCodes.idiv || opc == ByteCodes.imod 4024 || opc == ByteCodes.ldiv || opc == ByteCodes.lmod) { 4025 deferredLintHandler.report(() -> warnDivZero(pos)); 4026 } 4027 } 4028 } 4029 4030 /** 4031 * Check for possible loss of precission 4032 * @param pos Position for error reporting. 4033 * @param found The computed type of the tree 4034 * @param req The computed type of the tree 4035 */ 4036 void checkLossOfPrecision(final DiagnosticPosition pos, Type found, Type req) { 4037 if (found.isNumeric() && req.isNumeric() && !types.isAssignable(found, req)) { 4038 deferredLintHandler.report(() -> { 4039 if (lint.isEnabled(LintCategory.LOSSY_CONVERSIONS)) 4040 log.warning(LintCategory.LOSSY_CONVERSIONS, 4041 pos, Warnings.PossibleLossOfPrecision(found, req)); 4042 }); 4043 } 4044 } 4045 4046 /** 4047 * Check for empty statements after if 4048 */ 4049 void checkEmptyIf(JCIf tree) { 4050 if (tree.thenpart.hasTag(SKIP) && tree.elsepart == null && 4051 lint.isEnabled(LintCategory.EMPTY)) 4052 log.warning(LintCategory.EMPTY, tree.thenpart.pos(), Warnings.EmptyIf); 4053 } 4054 4055 /** Check that symbol is unique in given scope. 4056 * @param pos Position for error reporting. 4057 * @param sym The symbol. 4058 * @param s The scope. 4059 */ 4060 boolean checkUnique(DiagnosticPosition pos, Symbol sym, Scope s) { 4061 if (sym.type.isErroneous()) 4062 return true; 4063 if (sym.owner.name == names.any) return false; 4064 for (Symbol byName : s.getSymbolsByName(sym.name, NON_RECURSIVE)) { 4065 if (sym != byName && 4066 (byName.flags() & CLASH) == 0 && 4067 sym.kind == byName.kind && 4068 sym.name != names.error && 4069 (sym.kind != MTH || 4070 types.hasSameArgs(sym.type, byName.type) || 4071 types.hasSameArgs(types.erasure(sym.type), types.erasure(byName.type)))) { 4072 if ((sym.flags() & VARARGS) != (byName.flags() & VARARGS)) { 4073 sym.flags_field |= CLASH; 4074 varargsDuplicateError(pos, sym, byName); 4075 return true; 4076 } else if (sym.kind == MTH && !types.hasSameArgs(sym.type, byName.type, false)) { 4077 duplicateErasureError(pos, sym, byName); 4078 sym.flags_field |= CLASH; 4079 return true; 4080 } else if ((sym.flags() & MATCH_BINDING) != 0 && 4081 (byName.flags() & MATCH_BINDING) != 0 && 4082 (byName.flags() & MATCH_BINDING_TO_OUTER) == 0) { 4083 if (!sym.type.isErroneous()) { 4084 log.error(pos, Errors.MatchBindingExists); 4085 sym.flags_field |= CLASH; 4086 } 4087 return false; 4088 } else { 4089 duplicateError(pos, byName); 4090 return false; 4091 } 4092 } 4093 } 4094 return true; 4095 } 4096 4097 /** Report duplicate declaration error. 4098 */ 4099 void duplicateErasureError(DiagnosticPosition pos, Symbol sym1, Symbol sym2) { 4100 if (!sym1.type.isErroneous() && !sym2.type.isErroneous()) { 4101 log.error(pos, Errors.NameClashSameErasure(sym1, sym2)); 4102 } 4103 } 4104 4105 /**Check that types imported through the ordinary imports don't clash with types imported 4106 * by other (static or ordinary) imports. Note that two static imports may import two clashing 4107 * types without an error on the imports. 4108 * @param toplevel The toplevel tree for which the test should be performed. 4109 */ 4110 void checkImportsUnique(JCCompilationUnit toplevel) { 4111 WriteableScope ordinallyImportedSoFar = WriteableScope.create(toplevel.packge); 4112 WriteableScope staticallyImportedSoFar = WriteableScope.create(toplevel.packge); 4113 WriteableScope topLevelScope = toplevel.toplevelScope; 4114 4115 for (JCTree def : toplevel.defs) { 4116 if (!def.hasTag(IMPORT)) 4117 continue; 4118 4119 JCImport imp = (JCImport) def; 4120 4121 if (imp.importScope == null) 4122 continue; 4123 4124 for (Symbol sym : imp.importScope.getSymbols(sym -> sym.kind == TYP)) { 4125 if (imp.isStatic()) { 4126 checkUniqueImport(imp.pos(), ordinallyImportedSoFar, staticallyImportedSoFar, topLevelScope, sym, true); 4127 staticallyImportedSoFar.enter(sym); 4128 } else { 4129 checkUniqueImport(imp.pos(), ordinallyImportedSoFar, staticallyImportedSoFar, topLevelScope, sym, false); 4130 ordinallyImportedSoFar.enter(sym); 4131 } 4132 } 4133 4134 imp.importScope = null; 4135 } 4136 } 4137 4138 /** Check that single-type import is not already imported or top-level defined, 4139 * but make an exception for two single-type imports which denote the same type. 4140 * @param pos Position for error reporting. 4141 * @param ordinallyImportedSoFar A Scope containing types imported so far through 4142 * ordinary imports. 4143 * @param staticallyImportedSoFar A Scope containing types imported so far through 4144 * static imports. 4145 * @param topLevelScope The current file's top-level Scope 4146 * @param sym The symbol. 4147 * @param staticImport Whether or not this was a static import 4148 */ 4149 private boolean checkUniqueImport(DiagnosticPosition pos, Scope ordinallyImportedSoFar, 4150 Scope staticallyImportedSoFar, Scope topLevelScope, 4151 Symbol sym, boolean staticImport) { 4152 Predicate<Symbol> duplicates = candidate -> candidate != sym && !candidate.type.isErroneous(); 4153 Symbol ordinaryClashing = ordinallyImportedSoFar.findFirst(sym.name, duplicates); 4154 Symbol staticClashing = null; 4155 if (ordinaryClashing == null && !staticImport) { 4156 staticClashing = staticallyImportedSoFar.findFirst(sym.name, duplicates); 4157 } 4158 if (ordinaryClashing != null || staticClashing != null) { 4159 if (ordinaryClashing != null) 4160 log.error(pos, Errors.AlreadyDefinedSingleImport(ordinaryClashing)); 4161 else 4162 log.error(pos, Errors.AlreadyDefinedStaticSingleImport(staticClashing)); 4163 return false; 4164 } 4165 Symbol clashing = topLevelScope.findFirst(sym.name, duplicates); 4166 if (clashing != null) { 4167 log.error(pos, Errors.AlreadyDefinedThisUnit(clashing)); 4168 return false; 4169 } 4170 return true; 4171 } 4172 4173 /** Check that a qualified name is in canonical form (for import decls). 4174 */ 4175 public void checkCanonical(JCTree tree) { 4176 if (!isCanonical(tree)) 4177 log.error(tree.pos(), 4178 Errors.ImportRequiresCanonical(TreeInfo.symbol(tree))); 4179 } 4180 // where 4181 private boolean isCanonical(JCTree tree) { 4182 while (tree.hasTag(SELECT)) { 4183 JCFieldAccess s = (JCFieldAccess) tree; 4184 if (s.sym.owner.getQualifiedName() != TreeInfo.symbol(s.selected).getQualifiedName()) 4185 return false; 4186 tree = s.selected; 4187 } 4188 return true; 4189 } 4190 4191 /** Check that an auxiliary class is not accessed from any other file than its own. 4192 */ 4193 void checkForBadAuxiliaryClassAccess(DiagnosticPosition pos, Env<AttrContext> env, ClassSymbol c) { 4194 if (lint.isEnabled(Lint.LintCategory.AUXILIARYCLASS) && 4195 (c.flags() & AUXILIARY) != 0 && 4196 rs.isAccessible(env, c) && 4197 !fileManager.isSameFile(c.sourcefile, env.toplevel.sourcefile)) 4198 { 4199 log.warning(pos, 4200 Warnings.AuxiliaryClassAccessedFromOutsideOfItsSourceFile(c, c.sourcefile)); 4201 } 4202 } 4203 4204 /** 4205 * Check for a default constructor in an exported package. 4206 */ 4207 void checkDefaultConstructor(ClassSymbol c, DiagnosticPosition pos) { 4208 if (lint.isEnabled(LintCategory.MISSING_EXPLICIT_CTOR) && 4209 ((c.flags() & (ENUM | RECORD)) == 0) && 4210 !c.isAnonymous() && 4211 ((c.flags() & (PUBLIC | PROTECTED)) != 0) && 4212 Feature.MODULES.allowedInSource(source)) { 4213 NestingKind nestingKind = c.getNestingKind(); 4214 switch (nestingKind) { 4215 case ANONYMOUS, 4216 LOCAL -> {return;} 4217 case TOP_LEVEL -> {;} // No additional checks needed 4218 case MEMBER -> { 4219 // For nested member classes, all the enclosing 4220 // classes must be public or protected. 4221 Symbol owner = c.owner; 4222 while (owner != null && owner.kind == TYP) { 4223 if ((owner.flags() & (PUBLIC | PROTECTED)) == 0) 4224 return; 4225 owner = owner.owner; 4226 } 4227 } 4228 } 4229 4230 // Only check classes in named packages exported by its module 4231 PackageSymbol pkg = c.packge(); 4232 if (!pkg.isUnnamed()) { 4233 ModuleSymbol modle = pkg.modle; 4234 for (ExportsDirective exportDir : modle.exports) { 4235 // Report warning only if the containing 4236 // package is unconditionally exported 4237 if (exportDir.packge.equals(pkg)) { 4238 if (exportDir.modules == null || exportDir.modules.isEmpty()) { 4239 // Warning may be suppressed by 4240 // annotations; check again for being 4241 // enabled in the deferred context. 4242 deferredLintHandler.report(() -> { 4243 if (lint.isEnabled(LintCategory.MISSING_EXPLICIT_CTOR)) 4244 log.warning(LintCategory.MISSING_EXPLICIT_CTOR, 4245 pos, Warnings.MissingExplicitCtor(c, pkg, modle)); 4246 }); 4247 } else { 4248 return; 4249 } 4250 } 4251 } 4252 } 4253 } 4254 return; 4255 } 4256 4257 private class ConversionWarner extends Warner { 4258 final String uncheckedKey; 4259 final Type found; 4260 final Type expected; 4261 public ConversionWarner(DiagnosticPosition pos, String uncheckedKey, Type found, Type expected) { 4262 super(pos); 4263 this.uncheckedKey = uncheckedKey; 4264 this.found = found; 4265 this.expected = expected; 4266 } 4267 4268 @Override 4269 public void warn(LintCategory lint) { 4270 boolean warned = this.warned; 4271 super.warn(lint); 4272 if (warned) return; // suppress redundant diagnostics 4273 switch (lint) { 4274 case UNCHECKED: 4275 Check.this.warnUnchecked(pos(), Warnings.ProbFoundReq(diags.fragment(uncheckedKey), found, expected)); 4276 break; 4277 case VARARGS: 4278 if (method != null && 4279 method.attribute(syms.trustMeType.tsym) != null && 4280 isTrustMeAllowedOnMethod(method) && 4281 !types.isReifiable(method.type.getParameterTypes().last())) { 4282 Check.this.warnUnsafeVararg(pos(), Warnings.VarargsUnsafeUseVarargsParam(method.params.last())); 4283 } 4284 break; 4285 default: 4286 throw new AssertionError("Unexpected lint: " + lint); 4287 } 4288 } 4289 } 4290 4291 public Warner castWarner(DiagnosticPosition pos, Type found, Type expected) { 4292 return new ConversionWarner(pos, "unchecked.cast.to.type", found, expected); 4293 } 4294 4295 public Warner convertWarner(DiagnosticPosition pos, Type found, Type expected) { 4296 return new ConversionWarner(pos, "unchecked.assign", found, expected); 4297 } 4298 4299 public void checkFunctionalInterface(JCClassDecl tree, ClassSymbol cs) { 4300 Compound functionalType = cs.attribute(syms.functionalInterfaceType.tsym); 4301 4302 if (functionalType != null) { 4303 try { 4304 types.findDescriptorSymbol((TypeSymbol)cs); 4305 } catch (Types.FunctionDescriptorLookupError ex) { 4306 DiagnosticPosition pos = tree.pos(); 4307 for (JCAnnotation a : tree.getModifiers().annotations) { 4308 if (a.annotationType.type.tsym == syms.functionalInterfaceType.tsym) { 4309 pos = a.pos(); 4310 break; 4311 } 4312 } 4313 log.error(pos, Errors.BadFunctionalIntfAnno1(ex.getDiagnostic())); 4314 } 4315 } 4316 } 4317 4318 public void checkImportsResolvable(final JCCompilationUnit toplevel) { 4319 for (final JCImport imp : toplevel.getImports()) { 4320 if (!imp.staticImport || !imp.qualid.hasTag(SELECT)) 4321 continue; 4322 final JCFieldAccess select = (JCFieldAccess) imp.qualid; 4323 final Symbol origin; 4324 if (select.name == names.asterisk || (origin = TreeInfo.symbol(select.selected)) == null || origin.kind != TYP) 4325 continue; 4326 4327 TypeSymbol site = (TypeSymbol) TreeInfo.symbol(select.selected); 4328 if (!checkTypeContainsImportableElement(site, site, toplevel.packge, select.name, new HashSet<Symbol>())) { 4329 log.error(imp.pos(), 4330 Errors.CantResolveLocation(KindName.STATIC, 4331 select.name, 4332 null, 4333 null, 4334 Fragments.Location(kindName(site), 4335 site, 4336 null))); 4337 } 4338 } 4339 } 4340 4341 // Check that packages imported are in scope (JLS 7.4.3, 6.3, 6.5.3.1, 6.5.3.2) 4342 public void checkImportedPackagesObservable(final JCCompilationUnit toplevel) { 4343 OUTER: for (JCImport imp : toplevel.getImports()) { 4344 if (!imp.staticImport && TreeInfo.name(imp.qualid) == names.asterisk) { 4345 TypeSymbol tsym = ((JCFieldAccess)imp.qualid).selected.type.tsym; 4346 if (tsym.kind == PCK && tsym.members().isEmpty() && 4347 !(Feature.IMPORT_ON_DEMAND_OBSERVABLE_PACKAGES.allowedInSource(source) && tsym.exists())) { 4348 log.error(DiagnosticFlag.RESOLVE_ERROR, imp.pos, Errors.DoesntExist(tsym)); 4349 } 4350 } 4351 } 4352 } 4353 4354 private boolean checkTypeContainsImportableElement(TypeSymbol tsym, TypeSymbol origin, PackageSymbol packge, Name name, Set<Symbol> processed) { 4355 if (tsym == null || !processed.add(tsym)) 4356 return false; 4357 4358 // also search through inherited names 4359 if (checkTypeContainsImportableElement(types.supertype(tsym.type).tsym, origin, packge, name, processed)) 4360 return true; 4361 4362 for (Type t : types.interfaces(tsym.type)) 4363 if (checkTypeContainsImportableElement(t.tsym, origin, packge, name, processed)) 4364 return true; 4365 4366 for (Symbol sym : tsym.members().getSymbolsByName(name)) { 4367 if (sym.isStatic() && 4368 importAccessible(sym, packge) && 4369 sym.isMemberOf(origin, types)) { 4370 return true; 4371 } 4372 } 4373 4374 return false; 4375 } 4376 4377 // is the sym accessible everywhere in packge? 4378 public boolean importAccessible(Symbol sym, PackageSymbol packge) { 4379 try { 4380 int flags = (int)(sym.flags() & AccessFlags); 4381 switch (flags) { 4382 default: 4383 case PUBLIC: 4384 return true; 4385 case PRIVATE: 4386 return false; 4387 case 0: 4388 case PROTECTED: 4389 return sym.packge() == packge; 4390 } 4391 } catch (ClassFinder.BadClassFile err) { 4392 throw err; 4393 } catch (CompletionFailure ex) { 4394 return false; 4395 } 4396 } 4397 4398 public void checkLeaksNotAccessible(Env<AttrContext> env, JCClassDecl check) { 4399 JCCompilationUnit toplevel = env.toplevel; 4400 4401 if ( toplevel.modle == syms.unnamedModule 4402 || toplevel.modle == syms.noModule 4403 || (check.sym.flags() & COMPOUND) != 0) { 4404 return ; 4405 } 4406 4407 ExportsDirective currentExport = findExport(toplevel.packge); 4408 4409 if ( currentExport == null //not exported 4410 || currentExport.modules != null) //don't check classes in qualified export 4411 return ; 4412 4413 new TreeScanner() { 4414 Lint lint = env.info.lint; 4415 boolean inSuperType; 4416 4417 @Override 4418 public void visitBlock(JCBlock tree) { 4419 } 4420 @Override 4421 public void visitMethodDef(JCMethodDecl tree) { 4422 if (!isAPISymbol(tree.sym)) 4423 return; 4424 Lint prevLint = lint; 4425 try { 4426 lint = lint.augment(tree.sym); 4427 if (lint.isEnabled(LintCategory.EXPORTS)) { 4428 super.visitMethodDef(tree); 4429 } 4430 } finally { 4431 lint = prevLint; 4432 } 4433 } 4434 @Override 4435 public void visitVarDef(JCVariableDecl tree) { 4436 if (!isAPISymbol(tree.sym) && tree.sym.owner.kind != MTH) 4437 return; 4438 Lint prevLint = lint; 4439 try { 4440 lint = lint.augment(tree.sym); 4441 if (lint.isEnabled(LintCategory.EXPORTS)) { 4442 scan(tree.mods); 4443 scan(tree.vartype); 4444 } 4445 } finally { 4446 lint = prevLint; 4447 } 4448 } 4449 @Override 4450 public void visitClassDef(JCClassDecl tree) { 4451 if (tree != check) 4452 return ; 4453 4454 if (!isAPISymbol(tree.sym)) 4455 return ; 4456 4457 Lint prevLint = lint; 4458 try { 4459 lint = lint.augment(tree.sym); 4460 if (lint.isEnabled(LintCategory.EXPORTS)) { 4461 scan(tree.mods); 4462 scan(tree.typarams); 4463 try { 4464 inSuperType = true; 4465 scan(tree.extending); 4466 scan(tree.implementing); 4467 } finally { 4468 inSuperType = false; 4469 } 4470 scan(tree.defs); 4471 } 4472 } finally { 4473 lint = prevLint; 4474 } 4475 } 4476 @Override 4477 public void visitTypeApply(JCTypeApply tree) { 4478 scan(tree.clazz); 4479 boolean oldInSuperType = inSuperType; 4480 try { 4481 inSuperType = false; 4482 scan(tree.arguments); 4483 } finally { 4484 inSuperType = oldInSuperType; 4485 } 4486 } 4487 @Override 4488 public void visitIdent(JCIdent tree) { 4489 Symbol sym = TreeInfo.symbol(tree); 4490 if (sym.kind == TYP && !sym.type.hasTag(TYPEVAR)) { 4491 checkVisible(tree.pos(), sym, toplevel.packge, inSuperType); 4492 } 4493 } 4494 4495 @Override 4496 public void visitSelect(JCFieldAccess tree) { 4497 Symbol sym = TreeInfo.symbol(tree); 4498 Symbol sitesym = TreeInfo.symbol(tree.selected); 4499 if (sym.kind == TYP && sitesym.kind == PCK) { 4500 checkVisible(tree.pos(), sym, toplevel.packge, inSuperType); 4501 } else { 4502 super.visitSelect(tree); 4503 } 4504 } 4505 4506 @Override 4507 public void visitAnnotation(JCAnnotation tree) { 4508 if (tree.attribute.type.tsym.getAnnotation(java.lang.annotation.Documented.class) != null) 4509 super.visitAnnotation(tree); 4510 } 4511 4512 }.scan(check); 4513 } 4514 //where: 4515 private ExportsDirective findExport(PackageSymbol pack) { 4516 for (ExportsDirective d : pack.modle.exports) { 4517 if (d.packge == pack) 4518 return d; 4519 } 4520 4521 return null; 4522 } 4523 private boolean isAPISymbol(Symbol sym) { 4524 while (sym.kind != PCK) { 4525 if ((sym.flags() & Flags.PUBLIC) == 0 && (sym.flags() & Flags.PROTECTED) == 0) { 4526 return false; 4527 } 4528 sym = sym.owner; 4529 } 4530 return true; 4531 } 4532 private void checkVisible(DiagnosticPosition pos, Symbol what, PackageSymbol inPackage, boolean inSuperType) { 4533 if (!isAPISymbol(what) && !inSuperType) { //package private/private element 4534 log.warning(LintCategory.EXPORTS, pos, Warnings.LeaksNotAccessible(kindName(what), what, what.packge().modle)); 4535 return ; 4536 } 4537 4538 PackageSymbol whatPackage = what.packge(); 4539 ExportsDirective whatExport = findExport(whatPackage); 4540 ExportsDirective inExport = findExport(inPackage); 4541 4542 if (whatExport == null) { //package not exported: 4543 log.warning(LintCategory.EXPORTS, pos, Warnings.LeaksNotAccessibleUnexported(kindName(what), what, what.packge().modle)); 4544 return ; 4545 } 4546 4547 if (whatExport.modules != null) { 4548 if (inExport.modules == null || !whatExport.modules.containsAll(inExport.modules)) { 4549 log.warning(LintCategory.EXPORTS, pos, Warnings.LeaksNotAccessibleUnexportedQualified(kindName(what), what, what.packge().modle)); 4550 } 4551 } 4552 4553 if (whatPackage.modle != inPackage.modle && whatPackage.modle != syms.java_base) { 4554 //check that relativeTo.modle requires transitive what.modle, somehow: 4555 List<ModuleSymbol> todo = List.of(inPackage.modle); 4556 4557 while (todo.nonEmpty()) { 4558 ModuleSymbol current = todo.head; 4559 todo = todo.tail; 4560 if (current == whatPackage.modle) 4561 return ; //OK 4562 if ((current.flags() & Flags.AUTOMATIC_MODULE) != 0) 4563 continue; //for automatic modules, don't look into their dependencies 4564 for (RequiresDirective req : current.requires) { 4565 if (req.isTransitive()) { 4566 todo = todo.prepend(req.module); 4567 } 4568 } 4569 } 4570 4571 log.warning(LintCategory.EXPORTS, pos, Warnings.LeaksNotAccessibleNotRequiredTransitive(kindName(what), what, what.packge().modle)); 4572 } 4573 } 4574 4575 void checkModuleExists(final DiagnosticPosition pos, ModuleSymbol msym) { 4576 if (msym.kind != MDL) { 4577 deferredLintHandler.report(() -> { 4578 if (lint.isEnabled(LintCategory.MODULE)) 4579 log.warning(LintCategory.MODULE, pos, Warnings.ModuleNotFound(msym)); 4580 }); 4581 } 4582 } 4583 4584 void checkPackageExistsForOpens(final DiagnosticPosition pos, PackageSymbol packge) { 4585 if (packge.members().isEmpty() && 4586 ((packge.flags() & Flags.HAS_RESOURCE) == 0)) { 4587 deferredLintHandler.report(() -> { 4588 if (lint.isEnabled(LintCategory.OPENS)) 4589 log.warning(pos, Warnings.PackageEmptyOrNotFound(packge)); 4590 }); 4591 } 4592 } 4593 4594 void checkModuleRequires(final DiagnosticPosition pos, final RequiresDirective rd) { 4595 if ((rd.module.flags() & Flags.AUTOMATIC_MODULE) != 0) { 4596 deferredLintHandler.report(() -> { 4597 if (rd.isTransitive() && lint.isEnabled(LintCategory.REQUIRES_TRANSITIVE_AUTOMATIC)) { 4598 log.warning(pos, Warnings.RequiresTransitiveAutomatic); 4599 } else if (lint.isEnabled(LintCategory.REQUIRES_AUTOMATIC)) { 4600 log.warning(pos, Warnings.RequiresAutomatic); 4601 } 4602 }); 4603 } 4604 } 4605 4606 /** 4607 * Verify the case labels conform to the constraints. Checks constraints related 4608 * combinations of patterns and other labels. 4609 * 4610 * @param cases the cases that should be checked. 4611 */ 4612 void checkSwitchCaseStructure(List<JCCase> cases) { 4613 for (List<JCCase> l = cases; l.nonEmpty(); l = l.tail) { 4614 JCCase c = l.head; 4615 if (c.labels.head instanceof JCConstantCaseLabel constLabel) { 4616 if (TreeInfo.isNull(constLabel.expr)) { 4617 if (c.labels.tail.nonEmpty()) { 4618 if (c.labels.tail.head instanceof JCDefaultCaseLabel defLabel) { 4619 if (c.labels.tail.tail.nonEmpty()) { 4620 log.error(c.labels.tail.tail.head.pos(), Errors.InvalidCaseLabelCombination); 4621 } 4622 } else { 4623 log.error(c.labels.tail.head.pos(), Errors.InvalidCaseLabelCombination); 4624 } 4625 } 4626 } else { 4627 for (JCCaseLabel label : c.labels.tail) { 4628 if (!(label instanceof JCConstantCaseLabel) || TreeInfo.isNullCaseLabel(label)) { 4629 log.error(label.pos(), Errors.InvalidCaseLabelCombination); 4630 break; 4631 } 4632 } 4633 } 4634 } else { 4635 if (c.labels.tail.nonEmpty()) { 4636 log.error(c.labels.tail.head.pos(), Errors.FlowsThroughFromPattern); 4637 } 4638 } 4639 } 4640 4641 boolean isCaseStatementGroup = cases.nonEmpty() && 4642 cases.head.caseKind == CaseTree.CaseKind.STATEMENT; 4643 4644 if (isCaseStatementGroup) { 4645 boolean previousCompletessNormally = false; 4646 for (List<JCCase> l = cases; l.nonEmpty(); l = l.tail) { 4647 JCCase c = l.head; 4648 if (previousCompletessNormally && 4649 c.stats.nonEmpty() && 4650 c.labels.head instanceof JCPatternCaseLabel patternLabel && 4651 hasBindings(patternLabel.pat)) { 4652 log.error(c.labels.head.pos(), Errors.FlowsThroughToPattern); 4653 } else if (c.stats.isEmpty() && 4654 c.labels.head instanceof JCPatternCaseLabel patternLabel && 4655 hasBindings(patternLabel.pat) && 4656 hasStatements(l.tail)) { 4657 log.error(c.labels.head.pos(), Errors.FlowsThroughFromPattern); 4658 } 4659 previousCompletessNormally = c.completesNormally; 4660 } 4661 } 4662 } 4663 4664 boolean hasBindings(JCPattern p) { 4665 boolean[] bindings = new boolean[1]; 4666 4667 new TreeScanner() { 4668 @Override 4669 public void visitBindingPattern(JCBindingPattern tree) { 4670 bindings[0] = true; 4671 super.visitBindingPattern(tree); 4672 } 4673 }.scan(p); 4674 4675 return bindings[0]; 4676 } 4677 4678 boolean hasStatements(List<JCCase> cases) { 4679 for (List<JCCase> l = cases; l.nonEmpty(); l = l.tail) { 4680 if (l.head.stats.nonEmpty()) { 4681 return true; 4682 } 4683 } 4684 4685 return false; 4686 } 4687 void checkSwitchCaseLabelDominated(List<JCCase> cases) { 4688 List<JCCaseLabel> caseLabels = List.nil(); 4689 boolean seenDefault = false; 4690 boolean seenDefaultLabel = false; 4691 boolean warnDominatedByDefault = false; 4692 for (List<JCCase> l = cases; l.nonEmpty(); l = l.tail) { 4693 JCCase c = l.head; 4694 for (JCCaseLabel label : c.labels) { 4695 if (label.hasTag(DEFAULTCASELABEL)) { 4696 seenDefault = true; 4697 seenDefaultLabel |= 4698 TreeInfo.isNullCaseLabel(c.labels.head); 4699 continue; 4700 } 4701 if (TreeInfo.isNullCaseLabel(label)) { 4702 if (seenDefault) { 4703 log.error(label.pos(), Errors.PatternDominated); 4704 } 4705 continue; 4706 } 4707 if (seenDefault && !warnDominatedByDefault) { 4708 if (label.hasTag(PATTERNCASELABEL) || 4709 (label instanceof JCConstantCaseLabel && seenDefaultLabel)) { 4710 log.error(label.pos(), Errors.PatternDominated); 4711 warnDominatedByDefault = true; 4712 } 4713 } 4714 Type currentType = labelType(label); 4715 for (JCCaseLabel testCaseLabel : caseLabels) { 4716 Type testType = labelType(testCaseLabel); 4717 if (types.isSubtype(currentType, testType) && 4718 !currentType.hasTag(ERROR) && !testType.hasTag(ERROR)) { 4719 //the current label is potentially dominated by the existing (test) label, check: 4720 boolean dominated = false; 4721 if (label instanceof JCConstantCaseLabel) { 4722 dominated |= !(testCaseLabel instanceof JCConstantCaseLabel); 4723 } else if (label instanceof JCPatternCaseLabel patternCL && 4724 testCaseLabel instanceof JCPatternCaseLabel testPatternCaseLabel && 4725 TreeInfo.unguardedCaseLabel(testCaseLabel)) { 4726 dominated = patternDominated(testPatternCaseLabel.pat, 4727 patternCL.pat); 4728 } 4729 if (dominated) { 4730 log.error(label.pos(), Errors.PatternDominated); 4731 } 4732 } 4733 } 4734 caseLabels = caseLabels.prepend(label); 4735 } 4736 } 4737 } 4738 //where: 4739 private Type labelType(JCCaseLabel label) { 4740 return types.erasure(switch (label.getTag()) { 4741 case PATTERNCASELABEL -> ((JCPatternCaseLabel) label).pat.type; 4742 case CONSTANTCASELABEL -> types.boxedTypeOrType(((JCConstantCaseLabel) label).expr.type); 4743 default -> throw Assert.error("Unexpected tree kind: " + label.getTag()); 4744 }); 4745 } 4746 private boolean patternDominated(JCPattern existingPattern, JCPattern currentPattern) { 4747 Type existingPatternType = types.erasure(existingPattern.type); 4748 Type currentPatternType = types.erasure(currentPattern.type); 4749 if (existingPatternType.isPrimitive() ^ currentPatternType.isPrimitive()) { 4750 return false; 4751 } 4752 if (existingPatternType.isPrimitive()) { 4753 return types.isSameType(existingPatternType, currentPatternType); 4754 } else { 4755 if (!types.isSubtype(currentPatternType, existingPatternType)) { 4756 return false; 4757 } 4758 } 4759 while (existingPattern instanceof JCParenthesizedPattern parenthesized) { 4760 existingPattern = parenthesized.pattern; 4761 } 4762 while (currentPattern instanceof JCParenthesizedPattern parenthesized) { 4763 currentPattern = parenthesized.pattern; 4764 } 4765 if (currentPattern instanceof JCBindingPattern) { 4766 return existingPattern instanceof JCBindingPattern; 4767 } else if (currentPattern instanceof JCRecordPattern currentRecordPattern) { 4768 if (existingPattern instanceof JCBindingPattern) { 4769 return true; 4770 } else if (existingPattern instanceof JCRecordPattern existingRecordPattern) { 4771 List<JCPattern> existingNested = existingRecordPattern.nested; 4772 List<JCPattern> currentNested = currentRecordPattern.nested; 4773 if (existingNested.size() != currentNested.size()) { 4774 return false; 4775 } 4776 while (existingNested.nonEmpty()) { 4777 if (!patternDominated(existingNested.head, currentNested.head)) { 4778 return false; 4779 } 4780 existingNested = existingNested.tail; 4781 currentNested = currentNested.tail; 4782 } 4783 return true; 4784 } else { 4785 Assert.error("Unknown pattern: " + existingPattern.getTag()); 4786 } 4787 } else { 4788 Assert.error("Unknown pattern: " + currentPattern.getTag()); 4789 } 4790 return false; 4791 } 4792 4793 /** check if a type is a subtype of Externalizable, if that is available. */ 4794 boolean isExternalizable(Type t) { 4795 try { 4796 syms.externalizableType.complete(); 4797 } 4798 catch (CompletionFailure e) { 4799 return false; 4800 } 4801 return types.isSubtype(t, syms.externalizableType); 4802 } 4803 4804 /** 4805 * Check structure of serialization declarations. 4806 */ 4807 public void checkSerialStructure(JCClassDecl tree, ClassSymbol c) { 4808 (new SerialTypeVisitor()).visit(c, tree); 4809 } 4810 4811 /** 4812 * This visitor will warn if a serialization-related field or 4813 * method is declared in a suspicious or incorrect way. In 4814 * particular, it will warn for cases where the runtime 4815 * serialization mechanism will silently ignore a mis-declared 4816 * entity. 4817 * 4818 * Distinguished serialization-related fields and methods: 4819 * 4820 * Methods: 4821 * 4822 * private void writeObject(ObjectOutputStream stream) throws IOException 4823 * ANY-ACCESS-MODIFIER Object writeReplace() throws ObjectStreamException 4824 * 4825 * private void readObject(ObjectInputStream stream) throws IOException, ClassNotFoundException 4826 * private void readObjectNoData() throws ObjectStreamException 4827 * ANY-ACCESS-MODIFIER Object readResolve() throws ObjectStreamException 4828 * 4829 * Fields: 4830 * 4831 * private static final long serialVersionUID 4832 * private static final ObjectStreamField[] serialPersistentFields 4833 * 4834 * Externalizable: methods defined on the interface 4835 * public void writeExternal(ObjectOutput) throws IOException 4836 * public void readExternal(ObjectInput) throws IOException 4837 */ 4838 private class SerialTypeVisitor extends ElementKindVisitor14<Void, JCClassDecl> { 4839 SerialTypeVisitor() { 4840 this.lint = Check.this.lint; 4841 } 4842 4843 private static final Set<String> serialMethodNames = 4844 Set.of("writeObject", "writeReplace", 4845 "readObject", "readObjectNoData", 4846 "readResolve"); 4847 4848 private static final Set<String> serialFieldNames = 4849 Set.of("serialVersionUID", "serialPersistentFields"); 4850 4851 // Type of serialPersistentFields 4852 private final Type OSF_TYPE = new Type.ArrayType(syms.objectStreamFieldType, syms.arrayClass); 4853 4854 Lint lint; 4855 4856 @Override 4857 public Void defaultAction(Element e, JCClassDecl p) { 4858 throw new IllegalArgumentException(Objects.requireNonNullElse(e.toString(), "")); 4859 } 4860 4861 @Override 4862 public Void visitType(TypeElement e, JCClassDecl p) { 4863 runUnderLint(e, p, (symbol, param) -> super.visitType(symbol, param)); 4864 return null; 4865 } 4866 4867 @Override 4868 public Void visitTypeAsClass(TypeElement e, 4869 JCClassDecl p) { 4870 // Anonymous classes filtered out by caller. 4871 4872 ClassSymbol c = (ClassSymbol)e; 4873 4874 checkCtorAccess(p, c); 4875 4876 // Check for missing serialVersionUID; check *not* done 4877 // for enums or records. 4878 VarSymbol svuidSym = null; 4879 for (Symbol sym : c.members().getSymbolsByName(names.serialVersionUID)) { 4880 if (sym.kind == VAR) { 4881 svuidSym = (VarSymbol)sym; 4882 break; 4883 } 4884 } 4885 4886 if (svuidSym == null) { 4887 log.warning(LintCategory.SERIAL, p.pos(), Warnings.MissingSVUID(c)); 4888 } 4889 4890 // Check for serialPersistentFields to gate checks for 4891 // non-serializable non-transient instance fields 4892 boolean serialPersistentFieldsPresent = 4893 c.members() 4894 .getSymbolsByName(names.serialPersistentFields, sym -> sym.kind == VAR) 4895 .iterator() 4896 .hasNext(); 4897 4898 // Check declarations of serialization-related methods and 4899 // fields 4900 for(Symbol el : c.getEnclosedElements()) { 4901 runUnderLint(el, p, (enclosed, tree) -> { 4902 String name = null; 4903 switch(enclosed.getKind()) { 4904 case FIELD -> { 4905 if (!serialPersistentFieldsPresent) { 4906 var flags = enclosed.flags(); 4907 if ( ((flags & TRANSIENT) == 0) && 4908 ((flags & STATIC) == 0)) { 4909 Type varType = enclosed.asType(); 4910 if (!canBeSerialized(varType)) { 4911 // Note per JLS arrays are 4912 // serializable even if the 4913 // component type is not. 4914 log.warning(LintCategory.SERIAL, 4915 TreeInfo.diagnosticPositionFor(enclosed, tree), 4916 Warnings.NonSerializableInstanceField); 4917 } else if (varType.hasTag(ARRAY)) { 4918 ArrayType arrayType = (ArrayType)varType; 4919 Type elementType = arrayType.elemtype; 4920 while (elementType.hasTag(ARRAY)) { 4921 arrayType = (ArrayType)elementType; 4922 elementType = arrayType.elemtype; 4923 } 4924 if (!canBeSerialized(elementType)) { 4925 log.warning(LintCategory.SERIAL, 4926 TreeInfo.diagnosticPositionFor(enclosed, tree), 4927 Warnings.NonSerializableInstanceFieldArray(elementType)); 4928 } 4929 } 4930 } 4931 } 4932 4933 name = enclosed.getSimpleName().toString(); 4934 if (serialFieldNames.contains(name)) { 4935 VarSymbol field = (VarSymbol)enclosed; 4936 switch (name) { 4937 case "serialVersionUID" -> checkSerialVersionUID(tree, e, field); 4938 case "serialPersistentFields" -> checkSerialPersistentFields(tree, e, field); 4939 default -> throw new AssertionError(); 4940 } 4941 } 4942 } 4943 4944 // Correctly checking the serialization-related 4945 // methods is subtle. For the methods declared to be 4946 // private or directly declared in the class, the 4947 // enclosed elements of the class can be checked in 4948 // turn. However, writeReplace and readResolve can be 4949 // declared in a superclass and inherited. Note that 4950 // the runtime lookup walks the superclass chain 4951 // looking for writeReplace/readResolve via 4952 // Class.getDeclaredMethod. This differs from calling 4953 // Elements.getAllMembers(TypeElement) as the latter 4954 // will also pull in default methods from 4955 // superinterfaces. In other words, the runtime checks 4956 // (which long predate default methods on interfaces) 4957 // do not admit the possibility of inheriting methods 4958 // this way, a difference from general inheritance. 4959 4960 // The current implementation just checks the enclosed 4961 // elements and does not directly check the inherited 4962 // methods. If all the types are being checked this is 4963 // less of a concern; however, there are cases that 4964 // could be missed. In particular, readResolve and 4965 // writeReplace could, in principle, by inherited from 4966 // a non-serializable superclass and thus not checked 4967 // even if compiled with a serializable child class. 4968 case METHOD -> { 4969 var method = (MethodSymbol)enclosed; 4970 name = method.getSimpleName().toString(); 4971 if (serialMethodNames.contains(name)) { 4972 switch (name) { 4973 case "writeObject" -> checkWriteObject(tree, e, method); 4974 case "writeReplace" -> checkWriteReplace(tree,e, method); 4975 case "readObject" -> checkReadObject(tree,e, method); 4976 case "readObjectNoData" -> checkReadObjectNoData(tree, e, method); 4977 case "readResolve" -> checkReadResolve(tree, e, method); 4978 default -> throw new AssertionError(); 4979 } 4980 } 4981 } 4982 } 4983 }); 4984 } 4985 4986 return null; 4987 } 4988 4989 boolean canBeSerialized(Type type) { 4990 return type.isPrimitive() || rs.isSerializable(type); 4991 } 4992 4993 /** 4994 * Check that Externalizable class needs a public no-arg 4995 * constructor. 4996 * 4997 * Check that a Serializable class has access to the no-arg 4998 * constructor of its first nonserializable superclass. 4999 */ 5000 private void checkCtorAccess(JCClassDecl tree, ClassSymbol c) { 5001 if (isExternalizable(c.type)) { 5002 for(var sym : c.getEnclosedElements()) { 5003 if (sym.isInitOrVNew() && 5004 ((sym.flags() & PUBLIC) == PUBLIC)) { 5005 if (((MethodSymbol)sym).getParameters().isEmpty()) { 5006 return; 5007 } 5008 } 5009 } 5010 log.warning(LintCategory.SERIAL, tree.pos(), 5011 Warnings.ExternalizableMissingPublicNoArgCtor); 5012 } else { 5013 // Approximate access to the no-arg constructor up in 5014 // the superclass chain by checking that the 5015 // constructor is not private. This may not handle 5016 // some cross-package situations correctly. 5017 Type superClass = c.getSuperclass(); 5018 // java.lang.Object is *not* Serializable so this loop 5019 // should terminate. 5020 while (rs.isSerializable(superClass) ) { 5021 try { 5022 superClass = (Type)((TypeElement)(((DeclaredType)superClass)).asElement()).getSuperclass(); 5023 } catch(ClassCastException cce) { 5024 return ; // Don't try to recover 5025 } 5026 } 5027 // Non-Serializable superclass 5028 try { 5029 ClassSymbol supertype = ((ClassSymbol)(((DeclaredType)superClass).asElement())); 5030 for(var sym : supertype.getEnclosedElements()) { 5031 if (sym.isInitOrVNew()) { 5032 MethodSymbol ctor = (MethodSymbol)sym; 5033 if (ctor.getParameters().isEmpty()) { 5034 if (((ctor.flags() & PRIVATE) == PRIVATE) || 5035 // Handle nested classes and implicit this$0 5036 (supertype.getNestingKind() == NestingKind.MEMBER && 5037 ((supertype.flags() & STATIC) == 0))) 5038 log.warning(LintCategory.SERIAL, tree.pos(), 5039 Warnings.SerializableMissingAccessNoArgCtor(supertype.getQualifiedName())); 5040 } 5041 } 5042 } 5043 } catch (ClassCastException cce) { 5044 return ; // Don't try to recover 5045 } 5046 return; 5047 } 5048 } 5049 5050 private void checkSerialVersionUID(JCClassDecl tree, Element e, VarSymbol svuid) { 5051 // To be effective, serialVersionUID must be marked static 5052 // and final, but private is recommended. But alas, in 5053 // practice there are many non-private serialVersionUID 5054 // fields. 5055 if ((svuid.flags() & (STATIC | FINAL)) != 5056 (STATIC | FINAL)) { 5057 log.warning(LintCategory.SERIAL, 5058 TreeInfo.diagnosticPositionFor(svuid, tree), 5059 Warnings.ImproperSVUID((Symbol)e)); 5060 } 5061 5062 // check svuid has type long 5063 if (!svuid.type.hasTag(LONG)) { 5064 log.warning(LintCategory.SERIAL, 5065 TreeInfo.diagnosticPositionFor(svuid, tree), 5066 Warnings.LongSVUID((Symbol)e)); 5067 } 5068 5069 if (svuid.getConstValue() == null) 5070 log.warning(LintCategory.SERIAL, 5071 TreeInfo.diagnosticPositionFor(svuid, tree), 5072 Warnings.ConstantSVUID((Symbol)e)); 5073 } 5074 5075 private void checkSerialPersistentFields(JCClassDecl tree, Element e, VarSymbol spf) { 5076 // To be effective, serialPersisentFields must be private, static, and final. 5077 if ((spf.flags() & (PRIVATE | STATIC | FINAL)) != 5078 (PRIVATE | STATIC | FINAL)) { 5079 log.warning(LintCategory.SERIAL, 5080 TreeInfo.diagnosticPositionFor(spf, tree), Warnings.ImproperSPF); 5081 } 5082 5083 if (!types.isSameType(spf.type, OSF_TYPE)) { 5084 log.warning(LintCategory.SERIAL, 5085 TreeInfo.diagnosticPositionFor(spf, tree), Warnings.OSFArraySPF); 5086 } 5087 5088 if (isExternalizable((Type)(e.asType()))) { 5089 log.warning(LintCategory.SERIAL, tree.pos(), 5090 Warnings.IneffectualSerialFieldExternalizable); 5091 } 5092 5093 // Warn if serialPersistentFields is initialized to a 5094 // literal null. 5095 JCTree spfDecl = TreeInfo.declarationFor(spf, tree); 5096 if (spfDecl != null && spfDecl.getTag() == VARDEF) { 5097 JCVariableDecl variableDef = (JCVariableDecl) spfDecl; 5098 JCExpression initExpr = variableDef.init; 5099 if (initExpr != null && TreeInfo.isNull(initExpr)) { 5100 log.warning(LintCategory.SERIAL, initExpr.pos(), 5101 Warnings.SPFNullInit); 5102 } 5103 } 5104 } 5105 5106 private void checkWriteObject(JCClassDecl tree, Element e, MethodSymbol method) { 5107 // The "synchronized" modifier is seen in the wild on 5108 // readObject and writeObject methods and is generally 5109 // innocuous. 5110 5111 // private void writeObject(ObjectOutputStream stream) throws IOException 5112 checkPrivateNonStaticMethod(tree, method); 5113 checkReturnType(tree, e, method, syms.voidType); 5114 checkOneArg(tree, e, method, syms.objectOutputStreamType); 5115 checkExceptions(tree, e, method, syms.ioExceptionType); 5116 checkExternalizable(tree, e, method); 5117 } 5118 5119 private void checkWriteReplace(JCClassDecl tree, Element e, MethodSymbol method) { 5120 // ANY-ACCESS-MODIFIER Object writeReplace() throws 5121 // ObjectStreamException 5122 5123 // Excluding abstract, could have a more complicated 5124 // rule based on abstract-ness of the class 5125 checkConcreteInstanceMethod(tree, e, method); 5126 checkReturnType(tree, e, method, syms.objectType); 5127 checkNoArgs(tree, e, method); 5128 checkExceptions(tree, e, method, syms.objectStreamExceptionType); 5129 } 5130 5131 private void checkReadObject(JCClassDecl tree, Element e, MethodSymbol method) { 5132 // The "synchronized" modifier is seen in the wild on 5133 // readObject and writeObject methods and is generally 5134 // innocuous. 5135 5136 // private void readObject(ObjectInputStream stream) 5137 // throws IOException, ClassNotFoundException 5138 checkPrivateNonStaticMethod(tree, method); 5139 checkReturnType(tree, e, method, syms.voidType); 5140 checkOneArg(tree, e, method, syms.objectInputStreamType); 5141 checkExceptions(tree, e, method, syms.ioExceptionType, syms.classNotFoundExceptionType); 5142 checkExternalizable(tree, e, method); 5143 } 5144 5145 private void checkReadObjectNoData(JCClassDecl tree, Element e, MethodSymbol method) { 5146 // private void readObjectNoData() throws ObjectStreamException 5147 checkPrivateNonStaticMethod(tree, method); 5148 checkReturnType(tree, e, method, syms.voidType); 5149 checkNoArgs(tree, e, method); 5150 checkExceptions(tree, e, method, syms.objectStreamExceptionType); 5151 checkExternalizable(tree, e, method); 5152 } 5153 5154 private void checkReadResolve(JCClassDecl tree, Element e, MethodSymbol method) { 5155 // ANY-ACCESS-MODIFIER Object readResolve() 5156 // throws ObjectStreamException 5157 5158 // Excluding abstract, could have a more complicated 5159 // rule based on abstract-ness of the class 5160 checkConcreteInstanceMethod(tree, e, method); 5161 checkReturnType(tree,e, method, syms.objectType); 5162 checkNoArgs(tree, e, method); 5163 checkExceptions(tree, e, method, syms.objectStreamExceptionType); 5164 } 5165 5166 void checkPrivateNonStaticMethod(JCClassDecl tree, MethodSymbol method) { 5167 var flags = method.flags(); 5168 if ((flags & PRIVATE) == 0) { 5169 log.warning(LintCategory.SERIAL, 5170 TreeInfo.diagnosticPositionFor(method, tree), 5171 Warnings.SerialMethodNotPrivate(method.getSimpleName())); 5172 } 5173 5174 if ((flags & STATIC) != 0) { 5175 log.warning(LintCategory.SERIAL, 5176 TreeInfo.diagnosticPositionFor(method, tree), 5177 Warnings.SerialMethodStatic(method.getSimpleName())); 5178 } 5179 } 5180 5181 /** 5182 * Per section 1.12 "Serialization of Enum Constants" of 5183 * the serialization specification, due to the special 5184 * serialization handling of enums, any writeObject, 5185 * readObject, writeReplace, and readResolve methods are 5186 * ignored as are serialPersistentFields and 5187 * serialVersionUID fields. 5188 */ 5189 @Override 5190 public Void visitTypeAsEnum(TypeElement e, 5191 JCClassDecl p) { 5192 for(Element el : e.getEnclosedElements()) { 5193 runUnderLint(el, p, (enclosed, tree) -> { 5194 String name = enclosed.getSimpleName().toString(); 5195 switch(enclosed.getKind()) { 5196 case FIELD -> { 5197 if (serialFieldNames.contains(name)) { 5198 log.warning(LintCategory.SERIAL, tree.pos(), 5199 Warnings.IneffectualSerialFieldEnum(name)); 5200 } 5201 } 5202 5203 case METHOD -> { 5204 if (serialMethodNames.contains(name)) { 5205 log.warning(LintCategory.SERIAL, tree.pos(), 5206 Warnings.IneffectualSerialMethodEnum(name)); 5207 } 5208 } 5209 } 5210 }); 5211 } 5212 return null; 5213 } 5214 5215 /** 5216 * Most serialization-related fields and methods on interfaces 5217 * are ineffectual or problematic. 5218 */ 5219 @Override 5220 public Void visitTypeAsInterface(TypeElement e, 5221 JCClassDecl p) { 5222 for(Element el : e.getEnclosedElements()) { 5223 runUnderLint(el, p, (enclosed, tree) -> { 5224 String name = null; 5225 switch(enclosed.getKind()) { 5226 case FIELD -> { 5227 var field = (VarSymbol)enclosed; 5228 name = field.getSimpleName().toString(); 5229 switch(name) { 5230 case "serialPersistentFields" -> { 5231 log.warning(LintCategory.SERIAL, 5232 TreeInfo.diagnosticPositionFor(field, tree), 5233 Warnings.IneffectualSerialFieldInterface); 5234 } 5235 5236 case "serialVersionUID" -> { 5237 checkSerialVersionUID(tree, e, field); 5238 } 5239 } 5240 } 5241 5242 case METHOD -> { 5243 var method = (MethodSymbol)enclosed; 5244 name = enclosed.getSimpleName().toString(); 5245 if (serialMethodNames.contains(name)) { 5246 switch (name) { 5247 case 5248 "readObject", 5249 "readObjectNoData", 5250 "writeObject" -> checkPrivateMethod(tree, e, method); 5251 5252 case 5253 "writeReplace", 5254 "readResolve" -> checkDefaultIneffective(tree, e, method); 5255 5256 default -> throw new AssertionError(); 5257 } 5258 5259 } 5260 } 5261 } 5262 }); 5263 } 5264 5265 return null; 5266 } 5267 5268 private void checkPrivateMethod(JCClassDecl tree, 5269 Element e, 5270 MethodSymbol method) { 5271 if ((method.flags() & PRIVATE) == 0) { 5272 log.warning(LintCategory.SERIAL, 5273 TreeInfo.diagnosticPositionFor(method, tree), 5274 Warnings.NonPrivateMethodWeakerAccess); 5275 } 5276 } 5277 5278 private void checkDefaultIneffective(JCClassDecl tree, 5279 Element e, 5280 MethodSymbol method) { 5281 if ((method.flags() & DEFAULT) == DEFAULT) { 5282 log.warning(LintCategory.SERIAL, 5283 TreeInfo.diagnosticPositionFor(method, tree), 5284 Warnings.DefaultIneffective); 5285 5286 } 5287 } 5288 5289 @Override 5290 public Void visitTypeAsAnnotationType(TypeElement e, 5291 JCClassDecl p) { 5292 // Per the JLS, annotation types are not serializeable 5293 return null; 5294 } 5295 5296 /** 5297 * From the Java Object Serialization Specification, 1.13 5298 * Serialization of Records: 5299 * 5300 * "The process by which record objects are serialized or 5301 * externalized cannot be customized; any class-specific 5302 * writeObject, readObject, readObjectNoData, writeExternal, 5303 * and readExternal methods defined by record classes are 5304 * ignored during serialization and deserialization. However, 5305 * a substitute object to be serialized or a designate 5306 * replacement may be specified, by the writeReplace and 5307 * readResolve methods, respectively. Any 5308 * serialPersistentFields field declaration is 5309 * ignored. Documenting serializable fields and data for 5310 * record classes is unnecessary, since there is no variation 5311 * in the serial form, other than whether a substitute or 5312 * replacement object is used. The serialVersionUID of a 5313 * record class is 0L unless explicitly declared. The 5314 * requirement for matching serialVersionUID values is waived 5315 * for record classes." 5316 */ 5317 @Override 5318 public Void visitTypeAsRecord(TypeElement e, 5319 JCClassDecl p) { 5320 for(Element el : e.getEnclosedElements()) { 5321 runUnderLint(el, p, (enclosed, tree) -> { 5322 String name = enclosed.getSimpleName().toString(); 5323 switch(enclosed.getKind()) { 5324 case FIELD -> { 5325 switch(name) { 5326 case "serialPersistentFields" -> { 5327 log.warning(LintCategory.SERIAL, tree.pos(), 5328 Warnings.IneffectualSerialFieldRecord); 5329 } 5330 5331 case "serialVersionUID" -> { 5332 // Could generate additional warning that 5333 // svuid value is not checked to match for 5334 // records. 5335 checkSerialVersionUID(tree, e, (VarSymbol)enclosed); 5336 } 5337 5338 } 5339 } 5340 5341 case METHOD -> { 5342 var method = (MethodSymbol)enclosed; 5343 switch(name) { 5344 case "writeReplace" -> checkWriteReplace(tree, e, method); 5345 case "readResolve" -> checkReadResolve(tree, e, method); 5346 default -> { 5347 if (serialMethodNames.contains(name)) { 5348 log.warning(LintCategory.SERIAL, tree.pos(), 5349 Warnings.IneffectualSerialMethodRecord(name)); 5350 } 5351 } 5352 } 5353 5354 } 5355 } 5356 }); 5357 } 5358 return null; 5359 } 5360 5361 void checkConcreteInstanceMethod(JCClassDecl tree, 5362 Element enclosing, 5363 MethodSymbol method) { 5364 if ((method.flags() & (STATIC | ABSTRACT)) != 0) { 5365 log.warning(LintCategory.SERIAL, 5366 TreeInfo.diagnosticPositionFor(method, tree), 5367 Warnings.SerialConcreteInstanceMethod(method.getSimpleName())); 5368 } 5369 } 5370 5371 private void checkReturnType(JCClassDecl tree, 5372 Element enclosing, 5373 MethodSymbol method, 5374 Type expectedReturnType) { 5375 // Note: there may be complications checking writeReplace 5376 // and readResolve since they return Object and could, in 5377 // principle, have covariant overrides and any synthetic 5378 // bridge method would not be represented here for 5379 // checking. 5380 Type rtype = method.getReturnType(); 5381 if (!types.isSameType(expectedReturnType, rtype)) { 5382 log.warning(LintCategory.SERIAL, 5383 TreeInfo.diagnosticPositionFor(method, tree), 5384 Warnings.SerialMethodUnexpectedReturnType(method.getSimpleName(), 5385 rtype, expectedReturnType)); 5386 } 5387 } 5388 5389 private void checkOneArg(JCClassDecl tree, 5390 Element enclosing, 5391 MethodSymbol method, 5392 Type expectedType) { 5393 String name = method.getSimpleName().toString(); 5394 5395 var parameters= method.getParameters(); 5396 5397 if (parameters.size() != 1) { 5398 log.warning(LintCategory.SERIAL, 5399 TreeInfo.diagnosticPositionFor(method, tree), 5400 Warnings.SerialMethodOneArg(method.getSimpleName(), parameters.size())); 5401 return; 5402 } 5403 5404 Type parameterType = parameters.get(0).asType(); 5405 if (!types.isSameType(parameterType, expectedType)) { 5406 log.warning(LintCategory.SERIAL, 5407 TreeInfo.diagnosticPositionFor(method, tree), 5408 Warnings.SerialMethodParameterType(method.getSimpleName(), 5409 expectedType, 5410 parameterType)); 5411 } 5412 } 5413 5414 private void checkNoArgs(JCClassDecl tree, Element enclosing, MethodSymbol method) { 5415 var parameters = method.getParameters(); 5416 if (!parameters.isEmpty()) { 5417 log.warning(LintCategory.SERIAL, 5418 TreeInfo.diagnosticPositionFor(parameters.get(0), tree), 5419 Warnings.SerialMethodNoArgs(method.getSimpleName())); 5420 } 5421 } 5422 5423 private void checkExternalizable(JCClassDecl tree, Element enclosing, MethodSymbol method) { 5424 // If the enclosing class is externalizable, warn for the method 5425 if (isExternalizable((Type)enclosing.asType())) { 5426 log.warning(LintCategory.SERIAL, tree.pos(), 5427 Warnings.IneffectualSerialMethodExternalizable(method.getSimpleName())); 5428 } 5429 return; 5430 } 5431 5432 private void checkExceptions(JCClassDecl tree, 5433 Element enclosing, 5434 MethodSymbol method, 5435 Type... declaredExceptions) { 5436 for (Type thrownType: method.getThrownTypes()) { 5437 // For each exception in the throws clause of the 5438 // method, if not an Error and not a RuntimeException, 5439 // check if the exception is a subtype of a declared 5440 // exception from the throws clause of the 5441 // serialization method in question. 5442 if (types.isSubtype(thrownType, syms.runtimeExceptionType) || 5443 types.isSubtype(thrownType, syms.errorType) ) { 5444 continue; 5445 } else { 5446 boolean declared = false; 5447 for (Type declaredException : declaredExceptions) { 5448 if (types.isSubtype(thrownType, declaredException)) { 5449 declared = true; 5450 continue; 5451 } 5452 } 5453 if (!declared) { 5454 log.warning(LintCategory.SERIAL, 5455 TreeInfo.diagnosticPositionFor(method, tree), 5456 Warnings.SerialMethodUnexpectedException(method.getSimpleName(), 5457 thrownType)); 5458 } 5459 } 5460 } 5461 return; 5462 } 5463 5464 private <E extends Element> Void runUnderLint(E symbol, JCClassDecl p, BiConsumer<E, JCClassDecl> task) { 5465 Lint prevLint = lint; 5466 try { 5467 lint = lint.augment((Symbol) symbol); 5468 5469 if (lint.isEnabled(LintCategory.SERIAL)) { 5470 task.accept(symbol, p); 5471 } 5472 5473 return null; 5474 } finally { 5475 lint = prevLint; 5476 } 5477 } 5478 5479 } 5480 5481 }