| 1 | /* |
| 2 | * Copyright 1999-2006 Sun Microsystems, Inc. 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. Sun designates this |
| 8 | * particular file as subject to the "Classpath" exception as provided |
| 9 | * by Sun 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 Sun Microsystems, Inc., 4150 Network Circle, Santa Clara, |
| 22 | * CA 95054 USA or visit www.sun.com if you need additional information or |
| 23 | * have any questions. |
| 24 | */ |
| 25 | |
| 26 | package com.sun.tools.javac.comp; |
| 27 | |
| 28 | import java.util.*; |
| 29 | import java.util.Set; |
| 30 | |
| 31 | import com.sun.tools.javac.code.*; |
| 32 | import com.sun.tools.javac.jvm.*; |
| 33 | import com.sun.tools.javac.tree.*; |
| 34 | import com.sun.tools.javac.util.*; |
| 35 | import com.sun.tools.javac.util.JCDiagnostic.DiagnosticPosition; |
| 36 | import com.sun.tools.javac.util.List; |
| 37 | |
| 38 | import com.sun.tools.javac.tree.JCTree.*; |
| 39 | import com.sun.tools.javac.code.Lint; |
| 40 | import com.sun.tools.javac.code.Lint.LintCategory; |
| 41 | import com.sun.tools.javac.code.Type.*; |
| 42 | import com.sun.tools.javac.code.Symbol.*; |
| 43 | |
| 44 | import static com.sun.tools.javac.code.Flags.*; |
| 45 | import static com.sun.tools.javac.code.Kinds.*; |
| 46 | import static com.sun.tools.javac.code.TypeTags.*; |
| 47 | |
| 48 | /** Type checking helper class for the attribution phase. |
| 49 | * |
| 50 | * <p><b>This is NOT part of any API supported by Sun Microsystems. If |
| 51 | * you write code that depends on this, you do so at your own risk. |
| 52 | * This code and its internal interfaces are subject to change or |
| 53 | * deletion without notice.</b> |
| 54 | */ |
| 55 | public class Check { |
| 56 | protected static final Context.Key<Check> checkKey = |
| 57 | new Context.Key<Check>(); |
| 58 | |
| 59 | private final Name.Table names; |
| 60 | private final Log log; |
| 61 | private final Symtab syms; |
| 62 | private final Infer infer; |
| 63 | private final Target target; |
| 64 | private final Source source; |
| 65 | private final Types types; |
| 66 | private final boolean skipAnnotations; |
| 67 | private final TreeInfo treeinfo; |
| 68 | |
| 69 | // The set of lint options currently in effect. It is initialized |
| 70 | // from the context, and then is set/reset as needed by Attr as it |
| 71 | // visits all the various parts of the trees during attribution. |
| 72 | private Lint lint; |
| 73 | |
| 74 | public static Check instance(Context context) { |
| 75 | Check instance = context.get(checkKey); |
| 76 | if (instance == null) |
| 77 | instance = new Check(context); |
| 78 | return instance; |
| 79 | } |
| 80 | |
| 81 | protected Check(Context context) { |
| 82 | context.put(checkKey, this); |
| 83 | |
| 84 | names = Name.Table.instance(context); |
| 85 | log = Log.instance(context); |
| 86 | syms = Symtab.instance(context); |
| 87 | infer = Infer.instance(context); |
| 88 | this.types = Types.instance(context); |
| 89 | Options options = Options.instance(context); |
| 90 | target = Target.instance(context); |
| 91 | source = Source.instance(context); |
| 92 | lint = Lint.instance(context); |
| 93 | treeinfo = TreeInfo.instance(context); |
| 94 | |
| 95 | Source source = Source.instance(context); |
| 96 | allowGenerics = source.allowGenerics(); |
| 97 | allowAnnotations = source.allowAnnotations(); |
| 98 | complexInference = options.get("-complexinference") != null; |
| 99 | skipAnnotations = options.get("skipAnnotations") != null; |
| 100 | |
| 101 | boolean verboseDeprecated = lint.isEnabled(LintCategory.DEPRECATION); |
| 102 | boolean verboseUnchecked = lint.isEnabled(LintCategory.UNCHECKED); |
| 103 | |
| 104 | deprecationHandler = new MandatoryWarningHandler(log,verboseDeprecated, "deprecated"); |
| 105 | uncheckedHandler = new MandatoryWarningHandler(log, verboseUnchecked, "unchecked"); |
| 106 | } |
| 107 | |
| 108 | /** Switch: generics enabled? |
| 109 | */ |
| 110 | boolean allowGenerics; |
| 111 | |
| 112 | /** Switch: annotations enabled? |
| 113 | */ |
| 114 | boolean allowAnnotations; |
| 115 | |
| 116 | /** Switch: -complexinference option set? |
| 117 | */ |
| 118 | boolean complexInference; |
| 119 | |
| 120 | /** A table mapping flat names of all compiled classes in this run to their |
| 121 | * symbols; maintained from outside. |
| 122 | */ |
| 123 | public Map<Name,ClassSymbol> compiled = new HashMap<Name, ClassSymbol>(); |
| 124 | |
| 125 | /** A handler for messages about deprecated usage. |
| 126 | */ |
| 127 | private MandatoryWarningHandler deprecationHandler; |
| 128 | |
| 129 | /** A handler for messages about unchecked or unsafe usage. |
| 130 | */ |
| 131 | private MandatoryWarningHandler uncheckedHandler; |
| 132 | |
| 133 | |
| 134 | /* ************************************************************************* |
| 135 | * Errors and Warnings |
| 136 | **************************************************************************/ |
| 137 | |
| 138 | Lint setLint(Lint newLint) { |
| 139 | Lint prev = lint; |
| 140 | lint = newLint; |
| 141 | return prev; |
| 142 | } |
| 143 | |
| 144 | /** Warn about deprecated symbol. |
| 145 | * @param pos Position to be used for error reporting. |
| 146 | * @param sym The deprecated symbol. |
| 147 | */ |
| 148 | void warnDeprecated(DiagnosticPosition pos, Symbol sym) { |
| 149 | if (!lint.isSuppressed(LintCategory.DEPRECATION)) |
| 150 | deprecationHandler.report(pos, "has.been.deprecated", sym, sym.location()); |
| 151 | } |
| 152 | |
| 153 | /** Warn about unchecked operation. |
| 154 | * @param pos Position to be used for error reporting. |
| 155 | * @param msg A string describing the problem. |
| 156 | */ |
| 157 | public void warnUnchecked(DiagnosticPosition pos, String msg, Object... args) { |
| 158 | if (!lint.isSuppressed(LintCategory.UNCHECKED)) |
| 159 | uncheckedHandler.report(pos, msg, args); |
| 160 | } |
| 161 | |
| 162 | /** |
| 163 | * Report any deferred diagnostics. |
| 164 | */ |
| 165 | public void reportDeferredDiagnostics() { |
| 166 | deprecationHandler.reportDeferredDiagnostic(); |
| 167 | uncheckedHandler.reportDeferredDiagnostic(); |
| 168 | } |
| 169 | |
| 170 | |
| 171 | /** Report a failure to complete a class. |
| 172 | * @param pos Position to be used for error reporting. |
| 173 | * @param ex The failure to report. |
| 174 | */ |
| 175 | public Type completionError(DiagnosticPosition pos, CompletionFailure ex) { |
| 176 | log.error(pos, "cant.access", ex.sym, ex.errmsg); |
| 177 | if (ex instanceof ClassReader.BadClassFile) throw new Abort(); |
| 178 | else return syms.errType; |
| 179 | } |
| 180 | |
| 181 | /** Report a type error. |
| 182 | * @param pos Position to be used for error reporting. |
| 183 | * @param problem A string describing the error. |
| 184 | * @param found The type that was found. |
| 185 | * @param req The type that was required. |
| 186 | */ |
| 187 | Type typeError(DiagnosticPosition pos, Object problem, Type found, Type req) { |
| 188 | log.error(pos, "prob.found.req", |
| 189 | problem, found, req); |
| 190 | return syms.errType; |
| 191 | } |
| 192 | |
| 193 | Type typeError(DiagnosticPosition pos, String problem, Type found, Type req, Object explanation) { |
| 194 | log.error(pos, "prob.found.req.1", problem, found, req, explanation); |
| 195 | return syms.errType; |
| 196 | } |
| 197 | |
| 198 | /** Report an error that wrong type tag was found. |
| 199 | * @param pos Position to be used for error reporting. |
| 200 | * @param required An internationalized string describing the type tag |
| 201 | * required. |
| 202 | * @param found The type that was found. |
| 203 | */ |
| 204 | Type typeTagError(DiagnosticPosition pos, Object required, Object found) { |
| 205 | log.error(pos, "type.found.req", found, required); |
| 206 | return syms.errType; |
| 207 | } |
| 208 | |
| 209 | /** Report an error that symbol cannot be referenced before super |
| 210 | * has been called. |
| 211 | * @param pos Position to be used for error reporting. |
| 212 | * @param sym The referenced symbol. |
| 213 | */ |
| 214 | void earlyRefError(DiagnosticPosition pos, Symbol sym) { |
| 215 | log.error(pos, "cant.ref.before.ctor.called", sym); |
| 216 | } |
| 217 | |
| 218 | /** Report duplicate declaration error. |
| 219 | */ |
| 220 | void duplicateError(DiagnosticPosition pos, Symbol sym) { |
| 221 | if (!sym.type.isErroneous()) { |
| 222 | log.error(pos, "already.defined", sym, sym.location()); |
| 223 | } |
| 224 | } |
| 225 | |
| 226 | /** Report array/varargs duplicate declaration |
| 227 | */ |
| 228 | void varargsDuplicateError(DiagnosticPosition pos, Symbol sym1, Symbol sym2) { |
| 229 | if (!sym1.type.isErroneous() && !sym2.type.isErroneous()) { |
| 230 | log.error(pos, "array.and.varargs", sym1, sym2, sym2.location()); |
| 231 | } |
| 232 | } |
| 233 | |
| 234 | /* ************************************************************************ |
| 235 | * duplicate declaration checking |
| 236 | *************************************************************************/ |
| 237 | |
| 238 | /** Check that variable does not hide variable with same name in |
| 239 | * immediately enclosing local scope. |
| 240 | * @param pos Position for error reporting. |
| 241 | * @param v The symbol. |
| 242 | * @param s The scope. |
| 243 | */ |
| 244 | void checkTransparentVar(DiagnosticPosition pos, VarSymbol v, Scope s) { |
| 245 | if (s.next != null) { |
| 246 | for (Scope.Entry e = s.next.lookup(v.name); |
| 247 | e.scope != null && e.sym.owner == v.owner; |
| 248 | e = e.next()) { |
| 249 | if (e.sym.kind == VAR && |
| 250 | (e.sym.owner.kind & (VAR | MTH)) != 0 && |
| 251 | v.name != names.error) { |
| 252 | duplicateError(pos, e.sym); |
| 253 | return; |
| 254 | } |
| 255 | } |
| 256 | } |
| 257 | } |
| 258 | |
| 259 | /** Check that a class or interface does not hide a class or |
| 260 | * interface with same name in immediately enclosing local scope. |
| 261 | * @param pos Position for error reporting. |
| 262 | * @param c The symbol. |
| 263 | * @param s The scope. |
| 264 | */ |
| 265 | void checkTransparentClass(DiagnosticPosition pos, ClassSymbol c, Scope s) { |
| 266 | if (s.next != null) { |
| 267 | for (Scope.Entry e = s.next.lookup(c.name); |
| 268 | e.scope != null && e.sym.owner == c.owner; |
| 269 | e = e.next()) { |
| 270 | if (e.sym.kind == TYP && |
| 271 | (e.sym.owner.kind & (VAR | MTH)) != 0 && |
| 272 | c.name != names.error) { |
| 273 | duplicateError(pos, e.sym); |
| 274 | return; |
| 275 | } |
| 276 | } |
| 277 | } |
| 278 | } |
| 279 | |
| 280 | /** Check that class does not have the same name as one of |
| 281 | * its enclosing classes, or as a class defined in its enclosing scope. |
| 282 | * return true if class is unique in its enclosing scope. |
| 283 | * @param pos Position for error reporting. |
| 284 | * @param name The class name. |
| 285 | * @param s The enclosing scope. |
| 286 | */ |
| 287 | boolean checkUniqueClassName(DiagnosticPosition pos, Name name, Scope s) { |
| 288 | for (Scope.Entry e = s.lookup(name); e.scope == s; e = e.next()) { |
| 289 | if (e.sym.kind == TYP && e.sym.name != names.error) { |
| 290 | duplicateError(pos, e.sym); |
| 291 | return false; |
| 292 | } |
| 293 | } |
| 294 | for (Symbol sym = s.owner; sym != null; sym = sym.owner) { |
| 295 | if (sym.kind == TYP && sym.name == name && sym.name != names.error) { |
| 296 | duplicateError(pos, sym); |
| 297 | return true; |
| 298 | } |
| 299 | } |
| 300 | return true; |
| 301 | } |
| 302 | |
| 303 | /* ************************************************************************* |
| 304 | * Class name generation |
| 305 | **************************************************************************/ |
| 306 | |
| 307 | /** Return name of local class. |
| 308 | * This is of the form <enclClass> $ n <classname> |
| 309 | * where |
| 310 | * enclClass is the flat name of the enclosing class, |
| 311 | * classname is the simple name of the local class |
| 312 | */ |
| 313 | Name localClassName(ClassSymbol c) { |
| 314 | for (int i=1; ; i++) { |
| 315 | Name flatname = names. |
| 316 | fromString("" + c.owner.enclClass().flatname + |
| 317 | target.syntheticNameChar() + i + |
| 318 | c.name); |
| 319 | if (compiled.get(flatname) == null) return flatname; |
| 320 | } |
| 321 | } |
| 322 | |
| 323 | /* ************************************************************************* |
| 324 | * Type Checking |
| 325 | **************************************************************************/ |
| 326 | |
| 327 | /** Check that a given type is assignable to a given proto-type. |
| 328 | * If it is, return the type, otherwise return errType. |
| 329 | * @param pos Position to be used for error reporting. |
| 330 | * @param found The type that was found. |
| 331 | * @param req The type that was required. |
| 332 | */ |
| 333 | Type checkType(DiagnosticPosition pos, Type found, Type req) { |
| 334 | if (req.tag == ERROR) |
| 335 | return req; |
| 336 | if (found.tag == FORALL) |
| 337 | return instantiatePoly(pos, (ForAll)found, req, convertWarner(pos, found, req)); |
| 338 | if (req.tag == NONE) |
| 339 | return found; |
| 340 | if (types.isAssignable(found, req, convertWarner(pos, found, req))) |
| 341 | return found; |
| 342 | if (found.tag <= DOUBLE && req.tag <= DOUBLE) |
| 343 | return typeError(pos, JCDiagnostic.fragment("possible.loss.of.precision"), found, req); |
| 344 | if (found.isSuperBound()) { |
| 345 | log.error(pos, "assignment.from.super-bound", found); |
| 346 | return syms.errType; |
| 347 | } |
| 348 | if (req.isExtendsBound()) { |
| 349 | log.error(pos, "assignment.to.extends-bound", req); |
| 350 | return syms.errType; |
| 351 | } |
| 352 | return typeError(pos, JCDiagnostic.fragment("incompatible.types"), found, req); |
| 353 | } |
| 354 | |
| 355 | /** Instantiate polymorphic type to some prototype, unless |
| 356 | * prototype is `anyPoly' in which case polymorphic type |
| 357 | * is returned unchanged. |
| 358 | */ |
| 359 | Type instantiatePoly(DiagnosticPosition pos, ForAll t, Type pt, Warner warn) { |
| 360 | if (pt == Infer.anyPoly && complexInference) { |
| 361 | return t; |
| 362 | } else if (pt == Infer.anyPoly || pt.tag == NONE) { |
| 363 | Type newpt = t.qtype.tag <= VOID ? t.qtype : syms.objectType; |
| 364 | return instantiatePoly(pos, t, newpt, warn); |
| 365 | } else if (pt.tag == ERROR) { |
| 366 | return pt; |
| 367 | } else { |
| 368 | try { |
| 369 | return infer.instantiateExpr(t, pt, warn); |
| 370 | } catch (Infer.NoInstanceException ex) { |
| 371 | if (ex.isAmbiguous) { |
| 372 | JCDiagnostic d = ex.getDiagnostic(); |
| 373 | log.error(pos, |
| 374 | "undetermined.type" + (d!=null ? ".1" : ""), |
| 375 | t, d); |
| 376 | return syms.errType; |
| 377 | } else { |
| 378 | JCDiagnostic d = ex.getDiagnostic(); |
| 379 | return typeError(pos, |
| 380 | JCDiagnostic.fragment("incompatible.types" + (d!=null ? ".1" : ""), d), |
| 381 | t, pt); |
| 382 | } |
| 383 | } |
| 384 | } |
| 385 | } |
| 386 | |
| 387 | /** Check that a given type can be cast to a given target type. |
| 388 | * Return the result of the cast. |
| 389 | * @param pos Position to be used for error reporting. |
| 390 | * @param found The type that is being cast. |
| 391 | * @param req The target type of the cast. |
| 392 | */ |
| 393 | Type checkCastable(DiagnosticPosition pos, Type found, Type req) { |
| 394 | if (found.tag == FORALL) { |
| 395 | instantiatePoly(pos, (ForAll) found, req, castWarner(pos, found, req)); |
| 396 | return req; |
| 397 | } else if (types.isCastable(found, req, castWarner(pos, found, req))) { |
| 398 | return req; |
| 399 | } else { |
| 400 | return typeError(pos, |
| 401 | JCDiagnostic.fragment("inconvertible.types"), |
| 402 | found, req); |
| 403 | } |
| 404 | } |
| 405 | //where |
| 406 | /** Is type a type variable, or a (possibly multi-dimensional) array of |
| 407 | * type variables? |
| 408 | */ |
| 409 | boolean isTypeVar(Type t) { |
| 410 | return t.tag == TYPEVAR || t.tag == ARRAY && isTypeVar(types.elemtype(t)); |
| 411 | } |
| 412 | |
| 413 | /** Check that a type is within some bounds. |
| 414 | * |
| 415 | * Used in TypeApply to verify that, e.g., X in V<X> is a valid |
| 416 | * type argument. |
| 417 | * @param pos Position to be used for error reporting. |
| 418 | * @param a The type that should be bounded by bs. |
| 419 | * @param bs The bound. |
| 420 | */ |
| 421 | private void checkExtends(DiagnosticPosition pos, Type a, TypeVar bs) { |
| 422 | if (a.isUnbound()) { |
| 423 | return; |
| 424 | } else if (a.tag != WILDCARD) { |
| 425 | a = types.upperBound(a); |
| 426 | for (List<Type> l = types.getBounds(bs); l.nonEmpty(); l = l.tail) { |
| 427 | if (!types.isSubtype(a, l.head)) { |
| 428 | log.error(pos, "not.within.bounds", a); |
| 429 | return; |
| 430 | } |
| 431 | } |
| 432 | } else if (a.isExtendsBound()) { |
| 433 | if (!types.isCastable(bs.getUpperBound(), types.upperBound(a), Warner.noWarnings)) |
| 434 | log.error(pos, "not.within.bounds", a); |
| 435 | } else if (a.isSuperBound()) { |
| 436 | if (types.notSoftSubtype(types.lowerBound(a), bs.getUpperBound())) |
| 437 | log.error(pos, "not.within.bounds", a); |
| 438 | } |
| 439 | } |
| 440 | |
| 441 | /** Check that type is different from 'void'. |
| 442 | * @param pos Position to be used for error reporting. |
| 443 | * @param t The type to be checked. |
| 444 | */ |
| 445 | Type checkNonVoid(DiagnosticPosition pos, Type t) { |
| 446 | if (t.tag == VOID) { |
| 447 | log.error(pos, "void.not.allowed.here"); |
| 448 | return syms.errType; |
| 449 | } else { |
| 450 | return t; |
| 451 | } |
| 452 | } |
| 453 | |
| 454 | /** Check that type is a class or interface type. |
| 455 | * @param pos Position to be used for error reporting. |
| 456 | * @param t The type to be checked. |
| 457 | */ |
| 458 | Type checkClassType(DiagnosticPosition pos, Type t) { |
| 459 | if (t.tag != CLASS && t.tag != ERROR) |
| 460 | return typeTagError(pos, |
| 461 | JCDiagnostic.fragment("type.req.class"), |
| 462 | (t.tag == TYPEVAR) |
| 463 | ? JCDiagnostic.fragment("type.parameter", t) |
| 464 | : t); |
| 465 | else |
| 466 | return t; |
| 467 | } |
| 468 | |
| 469 | /** Check that type is a class or interface type. |
| 470 | * @param pos Position to be used for error reporting. |
| 471 | * @param t The type to be checked. |
| 472 | * @param noBounds True if type bounds are illegal here. |
| 473 | */ |
| 474 | Type checkClassType(DiagnosticPosition pos, Type t, boolean noBounds) { |
| 475 | t = checkClassType(pos, t); |
| 476 | if (noBounds && t.isParameterized()) { |
| 477 | List<Type> args = t.getTypeArguments(); |
| 478 | while (args.nonEmpty()) { |
| 479 | if (args.head.tag == WILDCARD) |
| 480 | return typeTagError(pos, |
| 481 | log.getLocalizedString("type.req.exact"), |
| 482 | args.head); |
| 483 | args = args.tail; |
| 484 | } |
| 485 | } |
| 486 | return t; |
| 487 | } |
| 488 | |
| 489 | /** Check that type is a reifiable class, interface or array type. |
| 490 | * @param pos Position to be used for error reporting. |
| 491 | * @param t The type to be checked. |
| 492 | */ |
| 493 | Type checkReifiableReferenceType(DiagnosticPosition pos, Type t) { |
| 494 | if (t.tag != CLASS && t.tag != ARRAY && t.tag != ERROR) { |
| 495 | return typeTagError(pos, |
| 496 | JCDiagnostic.fragment("type.req.class.array"), |
| 497 | t); |
| 498 | } else if (!types.isReifiable(t)) { |
| 499 | log.error(pos, "illegal.generic.type.for.instof"); |
| 500 | return syms.errType; |
| 501 | } else { |
| 502 | return t; |
| 503 | } |
| 504 | } |
| 505 | |
| 506 | /** Check that type is a reference type, i.e. a class, interface or array type |
| 507 | * or a type variable. |
| 508 | * @param pos Position to be used for error reporting. |
| 509 | * @param t The type to be checked. |
| 510 | */ |
| 511 | Type checkRefType(DiagnosticPosition pos, Type t) { |
| 512 | switch (t.tag) { |
| 513 | case CLASS: |
| 514 | case ARRAY: |
| 515 | case TYPEVAR: |
| 516 | case WILDCARD: |
| 517 | case ERROR: |
| 518 | return t; |
| 519 | default: |
| 520 | return typeTagError(pos, |
| 521 | JCDiagnostic.fragment("type.req.ref"), |
| 522 | t); |
| 523 | } |
| 524 | } |
| 525 | |
| 526 | /** Check that type is a null or reference type. |
| 527 | * @param pos Position to be used for error reporting. |
| 528 | * @param t The type to be checked. |
| 529 | */ |
| 530 | Type checkNullOrRefType(DiagnosticPosition pos, Type t) { |
| 531 | switch (t.tag) { |
| 532 | case CLASS: |
| 533 | case ARRAY: |
| 534 | case TYPEVAR: |
| 535 | case WILDCARD: |
| 536 | case BOT: |
| 537 | case ERROR: |
| 538 | return t; |
| 539 | default: |
| 540 | return typeTagError(pos, |
| 541 | JCDiagnostic.fragment("type.req.ref"), |
| 542 | t); |
| 543 | } |
| 544 | } |
| 545 | |
| 546 | /** Check that flag set does not contain elements of two conflicting sets. s |
| 547 | * Return true if it doesn't. |
| 548 | * @param pos Position to be used for error reporting. |
| 549 | * @param flags The set of flags to be checked. |
| 550 | * @param set1 Conflicting flags set #1. |
| 551 | * @param set2 Conflicting flags set #2. |
| 552 | */ |
| 553 | boolean checkDisjoint(DiagnosticPosition pos, long flags, long set1, long set2) { |
| 554 | if ((flags & set1) != 0 && (flags & set2) != 0) { |
| 555 | log.error(pos, |
| 556 | "illegal.combination.of.modifiers", |
| 557 | TreeInfo.flagNames(TreeInfo.firstFlag(flags & set1)), |
| 558 | TreeInfo.flagNames(TreeInfo.firstFlag(flags & set2))); |
| 559 | return false; |
| 560 | } else |
| 561 | return true; |
| 562 | } |
| 563 | |
| 564 | /** Check that given modifiers are legal for given symbol and |
| 565 | * return modifiers together with any implicit modififiers for that symbol. |
| 566 | * Warning: we can't use flags() here since this method |
| 567 | * is called during class enter, when flags() would cause a premature |
| 568 | * completion. |
| 569 | * @param pos Position to be used for error reporting. |
| 570 | * @param flags The set of modifiers given in a definition. |
| 571 | * @param sym The defined symbol. |
| 572 | */ |
| 573 | long checkFlags(DiagnosticPosition pos, long flags, Symbol sym, JCTree tree) { |
| 574 | long mask; |
| 575 | long implicit = 0; |
| 576 | switch (sym.kind) { |
| 577 | case VAR: |
| 578 | if (sym.owner.kind != TYP) |
| 579 | mask = LocalVarFlags; |
| 580 | else if ((sym.owner.flags_field & INTERFACE) != 0) |
| 581 | mask = implicit = InterfaceVarFlags; |
| 582 | else |
| 583 | mask = VarFlags; |
| 584 | break; |
| 585 | case MTH: |
| 586 | if (sym.name == names.init) { |
| 587 | if ((sym.owner.flags_field & ENUM) != 0) { |
| 588 | // enum constructors cannot be declared public or |
| 589 | // protected and must be implicitly or explicitly |
| 590 | // private |
| 591 | implicit = PRIVATE; |
| 592 | mask = PRIVATE; |
| 593 | } else |
| 594 | mask = ConstructorFlags; |
| 595 | } else if ((sym.owner.flags_field & INTERFACE) != 0) |
| 596 | mask = implicit = InterfaceMethodFlags; |
| 597 | else { |
| 598 | mask = MethodFlags; |
| 599 | } |
| 600 | // Imply STRICTFP if owner has STRICTFP set. |
| 601 | if (((flags|implicit) & Flags.ABSTRACT) == 0) |
| 602 | implicit |= sym.owner.flags_field & STRICTFP; |
| 603 | break; |
| 604 | case TYP: |
| 605 | if (sym.isLocal()) { |
| 606 | mask = LocalClassFlags; |
| 607 | if (sym.name.len == 0) { // Anonymous class |
| 608 | // Anonymous classes in static methods are themselves static; |
| 609 | // that's why we admit STATIC here. |
| 610 | mask |= STATIC; |
| 611 | // JLS: Anonymous classes are final. |
| 612 | implicit |= FINAL; |
| 613 | } |
| 614 | if ((sym.owner.flags_field & STATIC) == 0 && |
| 615 | (flags & ENUM) != 0) |
| 616 | log.error(pos, "enums.must.be.static"); |
| 617 | } else if (sym.owner.kind == TYP) { |
| 618 | mask = MemberClassFlags; |
| 619 | if (sym.owner.owner.kind == PCK || |
| 620 | (sym.owner.flags_field & STATIC) != 0) |
| 621 | mask |= STATIC; |
| 622 | else if ((flags & ENUM) != 0) |
| 623 | log.error(pos, "enums.must.be.static"); |
| 624 | // Nested interfaces and enums are always STATIC (Spec ???) |
| 625 | if ((flags & (INTERFACE | ENUM)) != 0 ) implicit = STATIC; |
| 626 | } else { |
| 627 | mask = ClassFlags; |
| 628 | } |
| 629 | // Interfaces are always ABSTRACT |
| 630 | if ((flags & INTERFACE) != 0) implicit |= ABSTRACT; |
| 631 | |
| 632 | if ((flags & ENUM) != 0) { |
| 633 | // enums can't be declared abstract or final |
| 634 | mask &= ~(ABSTRACT | FINAL); |
| 635 | implicit |= implicitEnumFinalFlag(tree); |
| 636 | } |
| 637 | // Imply STRICTFP if owner has STRICTFP set. |
| 638 | implicit |= sym.owner.flags_field & STRICTFP; |
| 639 | break; |
| 640 | default: |
| 641 | throw new AssertionError(); |
| 642 | } |
| 643 | long illegal = flags & StandardFlags & ~mask; |
| 644 | if (illegal != 0) { |
| 645 | if ((illegal & INTERFACE) != 0) { |
| 646 | log.error(pos, "intf.not.allowed.here"); |
| 647 | mask |= INTERFACE; |
| 648 | } |
| 649 | else { |
| 650 | log.error(pos, |
| 651 | "mod.not.allowed.here", TreeInfo.flagNames(illegal)); |
| 652 | } |
| 653 | } |
| 654 | else if ((sym.kind == TYP || |
| 655 | // ISSUE: Disallowing abstract&private is no longer appropriate |
| 656 | // in the presence of inner classes. Should it be deleted here? |
| 657 | checkDisjoint(pos, flags, |
| 658 | ABSTRACT, |
| 659 | PRIVATE | STATIC)) |
| 660 | && |
| 661 | checkDisjoint(pos, flags, |
| 662 | ABSTRACT | INTERFACE, |
| 663 | FINAL | NATIVE | SYNCHRONIZED) |
| 664 | && |
| 665 | checkDisjoint(pos, flags, |
| 666 | PUBLIC, |
| 667 | PRIVATE | PROTECTED) |
| 668 | && |
| 669 | checkDisjoint(pos, flags, |
| 670 | PRIVATE, |
| 671 | PUBLIC | PROTECTED) |
| 672 | && |
| 673 | checkDisjoint(pos, flags, |
| 674 | FINAL, |
| 675 | VOLATILE) |
| 676 | && |
| 677 | (sym.kind == TYP || |
| 678 | checkDisjoint(pos, flags, |
| 679 | ABSTRACT | NATIVE, |
| 680 | STRICTFP))) { |
| 681 | // skip |
| 682 | } |
| 683 | return flags & (mask | ~StandardFlags) | implicit; |
| 684 | } |
| 685 | |
| 686 | |
| 687 | /** Determine if this enum should be implicitly final. |
| 688 | * |
| 689 | * If the enum has no specialized enum contants, it is final. |
| 690 | * |
| 691 | * If the enum does have specialized enum contants, it is |
| 692 | * <i>not</i> final. |
| 693 | */ |
| 694 | private long implicitEnumFinalFlag(JCTree tree) { |
| 695 | if (tree.getTag() != JCTree.CLASSDEF) return 0; |
| 696 | class SpecialTreeVisitor extends JCTree.Visitor { |
| 697 | boolean specialized; |
| 698 | SpecialTreeVisitor() { |
| 699 | this.specialized = false; |
| 700 | }; |
| 701 | |
| 702 | public void visitTree(JCTree tree) { /* no-op */ } |
| 703 | |
| 704 | public void visitVarDef(JCVariableDecl tree) { |
| 705 | if ((tree.mods.flags & ENUM) != 0) { |
| 706 | if (tree.init instanceof JCNewClass && |
| 707 | ((JCNewClass) tree.init).def != null) { |
| 708 | specialized = true; |
| 709 | } |
| 710 | } |
| 711 | } |
| 712 | } |
| 713 | |
| 714 | SpecialTreeVisitor sts = new SpecialTreeVisitor(); |
| 715 | JCClassDecl cdef = (JCClassDecl) tree; |
| 716 | for (JCTree defs: cdef.defs) { |
| 717 | defs.accept(sts); |
| 718 | if (sts.specialized) return 0; |
| 719 | } |
| 720 | return FINAL; |
| 721 | } |
| 722 | |
| 723 | /* ************************************************************************* |
| 724 | * Type Validation |
| 725 | **************************************************************************/ |
| 726 | |
| 727 | /** Validate a type expression. That is, |
| 728 | * check that all type arguments of a parametric type are within |
| 729 | * their bounds. This must be done in a second phase after type attributon |
| 730 | * since a class might have a subclass as type parameter bound. E.g: |
| 731 | * |
| 732 | * class B<A extends C> { ... } |
| 733 | * class C extends B<C> { ... } |
| 734 | * |
| 735 | * and we can't make sure that the bound is already attributed because |
| 736 | * of possible cycles. |
| 737 | */ |
| 738 | private Validator validator = new Validator(); |
| 739 | |
| 740 | /** Visitor method: Validate a type expression, if it is not null, catching |
| 741 | * and reporting any completion failures. |
| 742 | */ |
| 743 | void validate(JCTree tree) { |
| 744 | try { |
| 745 | if (tree != null) tree.accept(validator); |
| 746 | } catch (CompletionFailure ex) { |
| 747 | completionError(tree.pos(), ex); |
| 748 | } |
| 749 | } |
| 750 | |
| 751 | /** Visitor method: Validate a list of type expressions. |
| 752 | */ |
| 753 | void validate(List<? extends JCTree> trees) { |
| 754 | for (List<? extends JCTree> l = trees; l.nonEmpty(); l = l.tail) |
| 755 | validate(l.head); |
| 756 | } |
| 757 | |
| 758 | /** Visitor method: Validate a list of type parameters. |
| 759 | */ |
| 760 | void validateTypeParams(List<JCTypeParameter> trees) { |
| 761 | for (List<JCTypeParameter> l = trees; l.nonEmpty(); l = l.tail) |
| 762 | validate(l.head); |
| 763 | } |
| 764 | |
| 765 | /** A visitor class for type validation. |
| 766 | */ |
| 767 | class Validator extends JCTree.Visitor { |
| 768 | |
| 769 | public void visitTypeArray(JCArrayTypeTree tree) { |
| 770 | validate(tree.elemtype); |
| 771 | } |
| 772 | |
| 773 | public void visitTypeApply(JCTypeApply tree) { |
| 774 | if (tree.type.tag == CLASS) { |
| 775 | List<Type> formals = tree.type.tsym.type.getTypeArguments(); |
| 776 | List<Type> actuals = tree.type.getTypeArguments(); |
| 777 | List<JCExpression> args = tree.arguments; |
| 778 | List<Type> forms = formals; |
| 779 | ListBuffer<TypeVar> tvars_buf = new ListBuffer<TypeVar>(); |
| 780 | |
| 781 | // For matching pairs of actual argument types `a' and |
| 782 | // formal type parameters with declared bound `b' ... |
| 783 | while (args.nonEmpty() && forms.nonEmpty()) { |
| 784 | validate(args.head); |
| 785 | |
| 786 | // exact type arguments needs to know their |
| 787 | // bounds (for upper and lower bound |
| 788 | // calculations). So we create new TypeVars with |
| 789 | // bounds substed with actuals. |
| 790 | tvars_buf.append(types.substBound(((TypeVar)forms.head), |
| 791 | formals, |
| 792 | Type.removeBounds(actuals))); |
| 793 | |
| 794 | args = args.tail; |
| 795 | forms = forms.tail; |
| 796 | } |
| 797 | |
| 798 | args = tree.arguments; |
| 799 | List<TypeVar> tvars = tvars_buf.toList(); |
| 800 | while (args.nonEmpty() && tvars.nonEmpty()) { |
| 801 | // Let the actual arguments know their bound |
| 802 | args.head.type.withTypeVar(tvars.head); |
| 803 | args = args.tail; |
| 804 | tvars = tvars.tail; |
| 805 | } |
| 806 | |
| 807 | args = tree.arguments; |
| 808 | tvars = tvars_buf.toList(); |
| 809 | while (args.nonEmpty() && tvars.nonEmpty()) { |
| 810 | checkExtends(args.head.pos(), |
| 811 | args.head.type, |
| 812 | tvars.head); |
| 813 | args = args.tail; |
| 814 | tvars = tvars.tail; |
| 815 | } |
| 816 | |
| 817 | // Check that this type is either fully parameterized, or |
| 818 | // not parameterized at all. |
| 819 | if (tree.type.getEnclosingType().isRaw()) |
| 820 | log.error(tree.pos(), "improperly.formed.type.inner.raw.param"); |
| 821 | if (tree.clazz.getTag() == JCTree.SELECT) |
| 822 | visitSelectInternal((JCFieldAccess)tree.clazz); |
| 823 | } |
| 824 | } |
| 825 | |
| 826 | public void visitTypeParameter(JCTypeParameter tree) { |
| 827 | validate(tree.bounds); |
| 828 | checkClassBounds(tree.pos(), tree.type); |
| 829 | } |
| 830 | |
| 831 | @Override |
| 832 | public void visitWildcard(JCWildcard tree) { |
| 833 | if (tree.inner != null) |
| 834 | validate(tree.inner); |
| 835 | } |
| 836 | |
| 837 | public void visitSelect(JCFieldAccess tree) { |
| 838 | if (tree.type.tag == CLASS) { |
| 839 | visitSelectInternal(tree); |
| 840 | |
| 841 | // Check that this type is either fully parameterized, or |
| 842 | // not parameterized at all. |
| 843 | if (tree.selected.type.isParameterized() && tree.type.tsym.type.getTypeArguments().nonEmpty()) |
| 844 | log.error(tree.pos(), "improperly.formed.type.param.missing"); |
| 845 | } |
| 846 | } |
| 847 | public void visitSelectInternal(JCFieldAccess tree) { |
| 848 | if (tree.type.getEnclosingType().tag != CLASS && |
| 849 | tree.selected.type.isParameterized()) { |
| 850 | // The enclosing type is not a class, so we are |
| 851 | // looking at a static member type. However, the |
| 852 | // qualifying expression is parameterized. |
| 853 | log.error(tree.pos(), "cant.select.static.class.from.param.type"); |
| 854 | } else { |
| 855 | // otherwise validate the rest of the expression |
| 856 | validate(tree.selected); |
| 857 | } |
| 858 | } |
| 859 | |
| 860 | /** Default visitor method: do nothing. |
| 861 | */ |
| 862 | public void visitTree(JCTree tree) { |
| 863 | } |
| 864 | } |
| 865 | |
| 866 | /* ************************************************************************* |
| 867 | * Exception checking |
| 868 | **************************************************************************/ |
| 869 | |
| 870 | /* The following methods treat classes as sets that contain |
| 871 | * the class itself and all their subclasses |
| 872 | */ |
| 873 | |
| 874 | /** Is given type a subtype of some of the types in given list? |
| 875 | */ |
| 876 | boolean subset(Type t, List<Type> ts) { |
| 877 | for (List<Type> l = ts; l.nonEmpty(); l = l.tail) |
| 878 | if (types.isSubtype(t, l.head)) return true; |
| 879 | return false; |
| 880 | } |
| 881 | |
| 882 | /** Is given type a subtype or supertype of |
| 883 | * some of the types in given list? |
| 884 | */ |
| 885 | boolean intersects(Type t, List<Type> ts) { |
| 886 | for (List<Type> l = ts; l.nonEmpty(); l = l.tail) |
| 887 | if (types.isSubtype(t, l.head) || types.isSubtype(l.head, t)) return true; |
| 888 | return false; |
| 889 | } |
| 890 | |
| 891 | /** Add type set to given type list, unless it is a subclass of some class |
| 892 | * in the list. |
| 893 | */ |
| 894 | List<Type> incl(Type t, List<Type> ts) { |
| 895 | return subset(t, ts) ? ts : excl(t, ts).prepend(t); |
| 896 | } |
| 897 | |
| 898 | /** Remove type set from type set list. |
| 899 | */ |
| 900 | List<Type> excl(Type t, List<Type> ts) { |
| 901 | if (ts.isEmpty()) { |
| 902 | return ts; |
| 903 | } else { |
| 904 | List<Type> ts1 = excl(t, ts.tail); |
| 905 | if (types.isSubtype(ts.head, t)) return ts1; |
| 906 | else if (ts1 == ts.tail) return ts; |
| 907 | else return ts1.prepend(ts.head); |
| 908 | } |
| 909 | } |
| 910 | |
| 911 | /** Form the union of two type set lists. |
| 912 | */ |
| 913 | List<Type> union(List<Type> ts1, List<Type> ts2) { |
| 914 | List<Type> ts = ts1; |
| 915 | for (List<Type> l = ts2; l.nonEmpty(); l = l.tail) |
| 916 | ts = incl(l.head, ts); |
| 917 | return ts; |
| 918 | } |
| 919 | |
| 920 | /** Form the difference of two type lists. |
| 921 | */ |
| 922 | List<Type> diff(List<Type> ts1, List<Type> ts2) { |
| 923 | List<Type> ts = ts1; |
| 924 | for (List<Type> l = ts2; l.nonEmpty(); l = l.tail) |
| 925 | ts = excl(l.head, ts); |
| 926 | return ts; |
| 927 | } |
| 928 | |
| 929 | /** Form the intersection of two type lists. |
| 930 | */ |
| 931 | public List<Type> intersect(List<Type> ts1, List<Type> ts2) { |
| 932 | List<Type> ts = List.nil(); |
| 933 | for (List<Type> l = ts1; l.nonEmpty(); l = l.tail) |
| 934 | if (subset(l.head, ts2)) ts = incl(l.head, ts); |
| 935 | for (List<Type> l = ts2; l.nonEmpty(); l = l.tail) |
| 936 | if (subset(l.head, ts1)) ts = incl(l.head, ts); |
| 937 | return ts; |
| 938 | } |
| 939 | |
| 940 | /** Is exc an exception symbol that need not be declared? |
| 941 | */ |
| 942 | boolean isUnchecked(ClassSymbol exc) { |
| 943 | return |
| 944 | exc.kind == ERR || |
| 945 | exc.isSubClass(syms.errorType.tsym, types) || |
| 946 | exc.isSubClass(syms.runtimeExceptionType.tsym, types); |
| 947 | } |
| 948 | |
| 949 | /** Is exc an exception type that need not be declared? |
| 950 | */ |
| 951 | boolean isUnchecked(Type exc) { |
| 952 | return |
| 953 | (exc.tag == TYPEVAR) ? isUnchecked(types.supertype(exc)) : |
| 954 | (exc.tag == CLASS) ? isUnchecked((ClassSymbol)exc.tsym) : |
| 955 | exc.tag == BOT; |
| 956 | } |
| 957 | |
| 958 | /** Same, but handling completion failures. |
| 959 | */ |
| 960 | boolean isUnchecked(DiagnosticPosition pos, Type exc) { |
| 961 | try { |
| 962 | return isUnchecked(exc); |
| 963 | } catch (CompletionFailure ex) { |
| 964 | completionError(pos, ex); |
| 965 | return true; |
| 966 | } |
| 967 | } |
| 968 | |
| 969 | /** Is exc handled by given exception list? |
| 970 | */ |
| 971 | boolean isHandled(Type exc, List<Type> handled) { |
| 972 | return isUnchecked(exc) || subset(exc, handled); |
| 973 | } |
| 974 | |
| 975 | /** Return all exceptions in thrown list that are not in handled list. |
| 976 | * @param thrown The list of thrown exceptions. |
| 977 | * @param handled The list of handled exceptions. |
| 978 | */ |
| 979 | List<Type> unHandled(List<Type> thrown, List<Type> handled) { |
| 980 | List<Type> unhandled = List.nil(); |
| 981 | for (List<Type> l = thrown; l.nonEmpty(); l = l.tail) |
| 982 | if (!isHandled(l.head, handled)) unhandled = unhandled.prepend(l.head); |
| 983 | return unhandled; |
| 984 | } |
| 985 | |
| 986 | /* ************************************************************************* |
| 987 | * Overriding/Implementation checking |
| 988 | **************************************************************************/ |
| 989 | |
| 990 | /** The level of access protection given by a flag set, |
| 991 | * where PRIVATE is highest and PUBLIC is lowest. |
| 992 | */ |
| 993 | static int protection(long flags) { |
| 994 | switch ((short)(flags & AccessFlags)) { |
| 995 | case PRIVATE: return 3; |
| 996 | case PROTECTED: return 1; |
| 997 | default: |
| 998 | case PUBLIC: return 0; |
| 999 | case 0: return 2; |
| 1000 | } |
| 1001 | } |
| 1002 | |
| 1003 | /** A string describing the access permission given by a flag set. |
| 1004 | * This always returns a space-separated list of Java Keywords. |
| 1005 | */ |
| 1006 | private static String protectionString(long flags) { |
| 1007 | long flags1 = flags & AccessFlags; |
| 1008 | return (flags1 == 0) ? "package" : TreeInfo.flagNames(flags1); |
| 1009 | } |
| 1010 | |
| 1011 | /** A customized "cannot override" error message. |
| 1012 | * @param m The overriding method. |
| 1013 | * @param other The overridden method. |
| 1014 | * @return An internationalized string. |
| 1015 | */ |
| 1016 | static Object cannotOverride(MethodSymbol m, MethodSymbol other) { |
| 1017 | String key; |
| 1018 | if ((other.owner.flags() & INTERFACE) == 0) |
| 1019 | key = "cant.override"; |
| 1020 | else if ((m.owner.flags() & INTERFACE) == 0) |
| 1021 | key = "cant.implement"; |
| 1022 | else |
| 1023 | key = "clashes.with"; |
| 1024 | return JCDiagnostic.fragment(key, m, m.location(), other, other.location()); |
| 1025 | } |
| 1026 | |
| 1027 | /** A customized "override" warning message. |
| 1028 | * @param m The overriding method. |
| 1029 | * @param other The overridden method. |
| 1030 | * @return An internationalized string. |
| 1031 | */ |
| 1032 | static Object uncheckedOverrides(MethodSymbol m, MethodSymbol other) { |
| 1033 | String key; |
| 1034 | if ((other.owner.flags() & INTERFACE) == 0) |
| 1035 | key = "unchecked.override"; |
| 1036 | else if ((m.owner.flags() & INTERFACE) == 0) |
| 1037 | key = "unchecked.implement"; |
| 1038 | else |
| 1039 | key = "unchecked.clash.with"; |
| 1040 | return JCDiagnostic.fragment(key, m, m.location(), other, other.location()); |
| 1041 | } |
| 1042 | |
| 1043 | /** A customized "override" warning message. |
| 1044 | * @param m The overriding method. |
| 1045 | * @param other The overridden method. |
| 1046 | * @return An internationalized string. |
| 1047 | */ |
| 1048 | static Object varargsOverrides(MethodSymbol m, MethodSymbol other) { |
| 1049 | String key; |
| 1050 | if ((other.owner.flags() & INTERFACE) == 0) |
| 1051 | key = "varargs.override"; |
| 1052 | else if ((m.owner.flags() & INTERFACE) == 0) |
| 1053 | key = "varargs.implement"; |
| 1054 | else |
| 1055 | key = "varargs.clash.with"; |
| 1056 | return JCDiagnostic.fragment(key, m, m.location(), other, other.location()); |
| 1057 | } |
| 1058 | |
| 1059 | /** Check that this method conforms with overridden method 'other'. |
| 1060 | * where `origin' is the class where checking started. |
| 1061 | * Complications: |
| 1062 | * (1) Do not check overriding of synthetic methods |
| 1063 | * (reason: they might be final). |
| 1064 | * todo: check whether this is still necessary. |
| 1065 | * (2) Admit the case where an interface proxy throws fewer exceptions |
| 1066 | * than the method it implements. Augment the proxy methods with the |
| 1067 | * undeclared exceptions in this case. |
| 1068 | * (3) When generics are enabled, admit the case where an interface proxy |
| 1069 | * has a result type |
| 1070 | * extended by the result type of the method it implements. |
| 1071 | * Change the proxies result type to the smaller type in this case. |
| 1072 | * |
| 1073 | * @param tree The tree from which positions |
| 1074 | * are extracted for errors. |
| 1075 | * @param m The overriding method. |
| 1076 | * @param other The overridden method. |
| 1077 | * @param origin The class of which the overriding method |
| 1078 | * is a member. |
| 1079 | */ |
| 1080 | void checkOverride(JCTree tree, |
| 1081 | MethodSymbol m, |
| 1082 | MethodSymbol other, |
| 1083 | ClassSymbol origin) { |
| 1084 | // Don't check overriding of synthetic methods or by bridge methods. |
| 1085 | if ((m.flags() & (SYNTHETIC|BRIDGE)) != 0 || (other.flags() & SYNTHETIC) != 0) { |
| 1086 | return; |
| 1087 | } |
| 1088 | |
| 1089 | // Error if static method overrides instance method (JLS 8.4.6.2). |
| 1090 | if ((m.flags() & STATIC) != 0 && |
| 1091 | (other.flags() & STATIC) == 0) { |
| 1092 | log.error(TreeInfo.diagnosticPositionFor(m, tree), "override.static", |
| 1093 | cannotOverride(m, other)); |
| 1094 | return; |
| 1095 | } |
| 1096 | |
| 1097 | // Error if instance method overrides static or final |
| 1098 | // method (JLS 8.4.6.1). |
| 1099 | if ((other.flags() & FINAL) != 0 || |
| 1100 | (m.flags() & STATIC) == 0 && |
| 1101 | (other.flags() & STATIC) != 0) { |
| 1102 | log.error(TreeInfo.diagnosticPositionFor(m, tree), "override.meth", |
| 1103 | cannotOverride(m, other), |
| 1104 | TreeInfo.flagNames(other.flags() & (FINAL | STATIC))); |
| 1105 | return; |
| 1106 | } |
| 1107 | |
| 1108 | if ((m.owner.flags() & ANNOTATION) != 0) { |
| 1109 | // handled in validateAnnotationMethod |
| 1110 | return; |
| 1111 | } |
| 1112 | |
| 1113 | // Error if overriding method has weaker access (JLS 8.4.6.3). |
| 1114 | if ((origin.flags() & INTERFACE) == 0 && |
| 1115 | protection(m.flags()) > protection(other.flags())) { |
| 1116 | log.error(TreeInfo.diagnosticPositionFor(m, tree), "override.weaker.access", |
| 1117 | cannotOverride(m, other), |
| 1118 | protectionString(other.flags())); |
| 1119 | return; |
| 1120 | |
| 1121 | } |
| 1122 | |
| 1123 | Type mt = types.memberType(origin.type, m); |
| 1124 | Type ot = types.memberType(origin.type, other); |
| 1125 | // Error if overriding result type is different |
| 1126 | // (or, in the case of generics mode, not a subtype) of |
| 1127 | // overridden result type. We have to rename any type parameters |
| 1128 | // before comparing types. |
| 1129 | List<Type> mtvars = mt.getTypeArguments(); |
| 1130 | List<Type> otvars = ot.getTypeArguments(); |
| 1131 | Type mtres = mt.getReturnType(); |
| 1132 | Type otres = types.subst(ot.getReturnType(), otvars, mtvars); |
| 1133 | |
| 1134 | overrideWarner.warned = false; |
| 1135 | boolean resultTypesOK = |
| 1136 | types.returnTypeSubstitutable(mt, ot, otres, overrideWarner); |
| 1137 | if (!resultTypesOK) { |
| 1138 | if (!source.allowCovariantReturns() && |
| 1139 | m.owner != origin && |
| 1140 | m.owner.isSubClass(other.owner, types)) { |
| 1141 | // allow limited interoperability with covariant returns |
| 1142 | } else { |
| 1143 | typeError(TreeInfo.diagnosticPositionFor(m, tree), |
| 1144 | JCDiagnostic.fragment("override.incompatible.ret", |
| 1145 | cannotOverride(m, other)), |
| 1146 | mtres, otres); |
| 1147 | return; |
| 1148 | } |
| 1149 | } else if (overrideWarner.warned) { |
| 1150 | warnUnchecked(TreeInfo.diagnosticPositionFor(m, tree), |
| 1151 | "prob.found.req", |
| 1152 | JCDiagnostic.fragment("override.unchecked.ret", |
| 1153 | uncheckedOverrides(m, other)), |
| 1154 | mtres, otres); |
| 1155 | } |
| 1156 | |
| 1157 | // Error if overriding method throws an exception not reported |
| 1158 | // by overridden method. |
| 1159 | List<Type> otthrown = types.subst(ot.getThrownTypes(), otvars, mtvars); |
| 1160 | List<Type> unhandled = unHandled(mt.getThrownTypes(), otthrown); |
| 1161 | if (unhandled.nonEmpty()) { |
| 1162 | log.error(TreeInfo.diagnosticPositionFor(m, tree), |
| 1163 | "override.meth.doesnt.throw", |
| 1164 | cannotOverride(m, other), |
| 1165 | unhandled.head); |
| 1166 | return; |
| 1167 | } |
| 1168 | |
| 1169 | // Optional warning if varargs don't agree |
| 1170 | if ((((m.flags() ^ other.flags()) & Flags.VARARGS) != 0) |
| 1171 | && lint.isEnabled(Lint.LintCategory.OVERRIDES)) { |
| 1172 | log.warning(TreeInfo.diagnosticPositionFor(m, tree), |
| 1173 | ((m.flags() & Flags.VARARGS) != 0) |
| 1174 | ? "override.varargs.missing" |
| 1175 | : "override.varargs.extra", |
| 1176 | varargsOverrides(m, other)); |
| 1177 | } |
| 1178 | |
| 1179 | // Warn if instance method overrides bridge method (compiler spec ??) |
| 1180 | if ((other.flags() & BRIDGE) != 0) { |
| 1181 | log.warning(TreeInfo.diagnosticPositionFor(m, tree), "override.bridge", |
| 1182 | uncheckedOverrides(m, other)); |
| 1183 | } |
| 1184 | |
| 1185 | // Warn if a deprecated method overridden by a non-deprecated one. |
| 1186 | if ((other.flags() & DEPRECATED) != 0 |
| 1187 | && (m.flags() & DEPRECATED) == 0 |
| 1188 | && m.outermostClass() != other.outermostClass() |
| 1189 | && !isDeprecatedOverrideIgnorable(other, origin)) { |
| 1190 | warnDeprecated(TreeInfo.diagnosticPositionFor(m, tree), other); |
| 1191 | } |
| 1192 | } |
| 1193 | // where |
| 1194 | private boolean isDeprecatedOverrideIgnorable(MethodSymbol m, ClassSymbol origin) { |
| 1195 | // If the method, m, is defined in an interface, then ignore the issue if the method |
| 1196 | // is only inherited via a supertype and also implemented in the supertype, |
| 1197 | // because in that case, we will rediscover the issue when examining the method |
| 1198 | // in the supertype. |
| 1199 | // If the method, m, is not defined in an interface, then the only time we need to |
| 1200 | // address the issue is when the method is the supertype implemementation: any other |
| 1201 | // case, we will have dealt with when examining the supertype classes |
| 1202 | ClassSymbol mc = m.enclClass(); |
| 1203 | Type st = types.supertype(origin.type); |
| 1204 | if (st.tag != CLASS) |
| 1205 | return true; |
| 1206 | MethodSymbol stimpl = m.implementation((ClassSymbol)st.tsym, types, false); |
| 1207 | |
| 1208 | if (mc != null && ((mc.flags() & INTERFACE) != 0)) { |
| 1209 | List<Type> intfs = types.interfaces(origin.type); |
| 1210 | return (intfs.contains(mc.type) ? false : (stimpl != null)); |
| 1211 | } |
| 1212 | else |
| 1213 | return (stimpl != m); |
| 1214 | } |
| 1215 | |
| 1216 | |
| 1217 | // used to check if there were any unchecked conversions |
| 1218 | Warner overrideWarner = new Warner(); |
| 1219 | |
| 1220 | /** Check that a class does not inherit two concrete methods |
| 1221 | * with the same signature. |
| 1222 | * @param pos Position to be used for error reporting. |
| 1223 | * @param site The class type to be checked. |
| 1224 | */ |
| 1225 | public void checkCompatibleConcretes(DiagnosticPosition pos, Type site) { |
| 1226 | Type sup = types.supertype(site); |
| 1227 | if (sup.tag != CLASS) return; |
| 1228 | |
| 1229 | for (Type t1 = sup; |
| 1230 | t1.tsym.type.isParameterized(); |
| 1231 | t1 = types.supertype(t1)) { |
| 1232 | for (Scope.Entry e1 = t1.tsym.members().elems; |
| 1233 | e1 != null; |
| 1234 | e1 = e1.sibling) { |
| 1235 | Symbol s1 = e1.sym; |
| 1236 | if (s1.kind != MTH || |
| 1237 | (s1.flags() & (STATIC|SYNTHETIC|BRIDGE)) != 0 || |
| 1238 | !s1.isInheritedIn(site.tsym, types) || |
| 1239 | ((MethodSymbol)s1).implementation(site.tsym, |
| 1240 | types, |
| 1241 | true) != s1) |
| 1242 | continue; |
| 1243 | Type st1 = types.memberType(t1, s1); |
| 1244 | int s1ArgsLength = st1.getParameterTypes().length(); |
| 1245 | if (st1 == s1.type) continue; |
| 1246 | |
| 1247 | for (Type t2 = sup; |
| 1248 | t2.tag == CLASS; |
| 1249 | t2 = types.supertype(t2)) { |
| 1250 | for (Scope.Entry e2 = t1.tsym.members().lookup(s1.name); |
| 1251 | e2.scope != null; |
| 1252 | e2 = e2.next()) { |
| 1253 | Symbol s2 = e2.sym; |
| 1254 | if (s2 == s1 || |
| 1255 | s2.kind != MTH || |
| 1256 | (s2.flags() & (STATIC|SYNTHETIC|BRIDGE)) != 0 || |
| 1257 | s2.type.getParameterTypes().length() != s1ArgsLength || |
| 1258 | !s2.isInheritedIn(site.tsym, types) || |
| 1259 | ((MethodSymbol)s2).implementation(site.tsym, |
| 1260 | types, |
| 1261 | true) != s2) |
| 1262 | continue; |
| 1263 | Type st2 = types.memberType(t2, s2); |
| 1264 | if (types.overrideEquivalent(st1, st2)) |
| 1265 | log.error(pos, "concrete.inheritance.conflict", |
| 1266 | s1, t1, s2, t2, sup); |
| 1267 | } |
| 1268 | } |
| 1269 | } |
| 1270 | } |
| 1271 | } |
| 1272 | |
| 1273 | /** Check that classes (or interfaces) do not each define an abstract |
| 1274 | * method with same name and arguments but incompatible return types. |
| 1275 | * @param pos Position to be used for error reporting. |
| 1276 | * @param t1 The first argument type. |
| 1277 | * @param t2 The second argument type. |
| 1278 | */ |
| 1279 | public boolean checkCompatibleAbstracts(DiagnosticPosition pos, |
| 1280 | Type t1, |
| 1281 | Type t2) { |
| 1282 | return checkCompatibleAbstracts(pos, t1, t2, |
| 1283 | types.makeCompoundType(t1, t2)); |
| 1284 | } |
| 1285 | |
| 1286 | public boolean checkCompatibleAbstracts(DiagnosticPosition pos, |
| 1287 | Type t1, |
| 1288 | Type t2, |
| 1289 | Type site) { |
| 1290 | Symbol sym = firstIncompatibility(t1, t2, site); |
| 1291 | if (sym != null) { |
| 1292 | log.error(pos, "types.incompatible.diff.ret", |
| 1293 | t1, t2, sym.name + |
| 1294 | "(" + types.memberType(t2, sym).getParameterTypes() + ")"); |
| 1295 | return false; |
| 1296 | } |
| 1297 | return true; |
| 1298 | } |
| 1299 | |
| 1300 | /** Return the first method which is defined with same args |
| 1301 | * but different return types in two given interfaces, or null if none |
| 1302 | * exists. |
| 1303 | * @param t1 The first type. |
| 1304 | * @param t2 The second type. |
| 1305 | * @param site The most derived type. |
| 1306 | * @returns symbol from t2 that conflicts with one in t1. |
| 1307 | */ |
| 1308 | private Symbol firstIncompatibility(Type t1, Type t2, Type site) { |
| 1309 | Map<TypeSymbol,Type> interfaces1 = new HashMap<TypeSymbol,Type>(); |
| 1310 | closure(t1, interfaces1); |
| 1311 | Map<TypeSymbol,Type> interfaces2; |
| 1312 | if (t1 == t2) |
| 1313 | interfaces2 = interfaces1; |
| 1314 | else |
| 1315 | closure(t2, interfaces1, interfaces2 = new HashMap<TypeSymbol,Type>()); |
| 1316 | |
| 1317 | for (Type t3 : interfaces1.values()) { |
| 1318 | for (Type t4 : interfaces2.values()) { |
| 1319 | Symbol s = firstDirectIncompatibility(t3, t4, site); |
| 1320 | if (s != null) return s; |
| 1321 | } |
| 1322 | } |
| 1323 | return null; |
| 1324 | } |
| 1325 | |
| 1326 | /** Compute all the supertypes of t, indexed by type symbol. */ |
| 1327 | private void closure(Type t, Map<TypeSymbol,Type> typeMap) { |
| 1328 | if (t.tag != CLASS) return; |
| 1329 | if (typeMap.put(t.tsym, t) == null) { |
| 1330 | closure(types.supertype(t), typeMap); |
| 1331 | for (Type i : types.interfaces(t)) |
| 1332 | closure(i, typeMap); |
| 1333 | } |
| 1334 | } |
| 1335 | |
| 1336 | /** Compute all the supertypes of t, indexed by type symbol (except thise in typesSkip). */ |
| 1337 | private void closure(Type t, Map<TypeSymbol,Type> typesSkip, Map<TypeSymbol,Type> typeMap) { |
| 1338 | if (t.tag != CLASS) return; |
| 1339 | if (typesSkip.get(t.tsym) != null) return; |
| 1340 | if (typeMap.put(t.tsym, t) == null) { |
| 1341 | closure(types.supertype(t), typesSkip, typeMap); |
| 1342 | for (Type i : types.interfaces(t)) |
| 1343 | closure(i, typesSkip, typeMap); |
| 1344 | } |
| 1345 | } |
| 1346 | |
| 1347 | /** Return the first method in t2 that conflicts with a method from t1. */ |
| 1348 | private Symbol firstDirectIncompatibility(Type t1, Type t2, Type site) { |
| 1349 | for (Scope.Entry e1 = t1.tsym.members().elems; e1 != null; e1 = e1.sibling) { |
| 1350 | Symbol s1 = e1.sym; |
| 1351 | Type st1 = null; |
| 1352 | if (s1.kind != MTH || !s1.isInheritedIn(site.tsym, types)) continue; |
| 1353 | Symbol impl = ((MethodSymbol)s1).implementation(site.tsym, types, false); |
| 1354 | if (impl != null && (impl.flags() & ABSTRACT) == 0) continue; |
| 1355 | for (Scope.Entry e2 = t2.tsym.members().lookup(s1.name); e2.scope != null; e2 = e2.next()) { |
| 1356 | Symbol s2 = e2.sym; |
| 1357 | if (s1 == s2) continue; |
| 1358 | if (s2.kind != MTH || !s2.isInheritedIn(site.tsym, types)) continue; |
| 1359 | if (st1 == null) st1 = types.memberType(t1, s1); |
| 1360 | Type st2 = types.memberType(t2, s2); |
| 1361 | if (types.overrideEquivalent(st1, st2)) { |
| 1362 | List<Type> tvars1 = st1.getTypeArguments(); |
| 1363 | List<Type> tvars2 = st2.getTypeArguments(); |
| 1364 | Type rt1 = st1.getReturnType(); |
| 1365 | Type rt2 = types.subst(st2.getReturnType(), tvars2, tvars1); |
| 1366 | boolean compat = |
| 1367 | types.isSameType(rt1, rt2) || |
| 1368 | rt1.tag >= CLASS && rt2.tag >= CLASS && |
| 1369 | (types.covariantReturnType(rt1, rt2, Warner.noWarnings) || |
| 1370 | types.covariantReturnType(rt2, rt1, Warner.noWarnings)); |
| 1371 | if (!compat) return s2; |
| 1372 | } |
| 1373 | } |
| 1374 | } |
| 1375 | return null; |
| 1376 | } |
| 1377 | |
| 1378 | /** Check that a given method conforms with any method it overrides. |
| 1379 | * @param tree The tree from which positions are extracted |
| 1380 | * for errors. |
| 1381 | * @param m The overriding method. |
| 1382 | */ |
| 1383 | void checkOverride(JCTree tree, MethodSymbol m) { |
| 1384 | ClassSymbol origin = (ClassSymbol)m.owner; |
| 1385 | if ((origin.flags() & ENUM) != 0 && names.finalize.equals(m.name)) |
| 1386 | if (m.overrides(syms.enumFinalFinalize, origin, types, false)) { |
| 1387 | log.error(tree.pos(), "enum.no.finalize"); |
| 1388 | return; |
| 1389 | } |
| 1390 | for (Type t = types.supertype(origin.type); t.tag == CLASS; |
| 1391 | t = types.supertype(t)) { |
| 1392 | TypeSymbol c = t.tsym; |
| 1393 | Scope.Entry e = c.members().lookup(m.name); |
| 1394 | while (e.scope != null) { |
| 1395 | if (m.overrides(e.sym, origin, types, false)) |
| 1396 | checkOverride(tree, m, (MethodSymbol)e.sym, origin); |
| 1397 | e = e.next(); |
| 1398 | } |
| 1399 | } |
| 1400 | } |
| 1401 | |
| 1402 | /** Check that all abstract members of given class have definitions. |
| 1403 | * @param pos Position to be used for error reporting. |
| 1404 | * @param c The class. |
| 1405 | */ |
| 1406 | void checkAllDefined(DiagnosticPosition pos, ClassSymbol c) { |
| 1407 | try { |
| 1408 | MethodSymbol undef = firstUndef(c, c); |
| 1409 | if (undef != null) { |
| 1410 | if ((c.flags() & ENUM) != 0 && |
| 1411 | types.supertype(c.type).tsym == syms.enumSym && |
| 1412 | (c.flags() & FINAL) == 0) { |
| 1413 | // add the ABSTRACT flag to an enum |
| 1414 | c.flags_field |= ABSTRACT; |
| 1415 | } else { |
| 1416 | MethodSymbol undef1 = |
| 1417 | new MethodSymbol(undef.flags(), undef.name, |
| 1418 | types.memberType(c.type, undef), undef.owner); |
| 1419 | log.error(pos, "does.not.override.abstract", |
| 1420 | c, undef1, undef1.location()); |
| 1421 | } |
| 1422 | } |
| 1423 | } catch (CompletionFailure ex) { |
| 1424 | completionError(pos, ex); |
| 1425 | } |
| 1426 | } |
| 1427 | //where |
| 1428 | /** Return first abstract member of class `c' that is not defined |
| 1429 | * in `impl', null if there is none. |
| 1430 | */ |
| 1431 | private MethodSymbol firstUndef(ClassSymbol impl, ClassSymbol c) { |
| 1432 | MethodSymbol undef = null; |
| 1433 | // Do not bother to search in classes that are not abstract, |
| 1434 | // since they cannot have abstract members. |
| 1435 | if (c == impl || (c.flags() & (ABSTRACT | INTERFACE)) != 0) { |
| 1436 | Scope s = c.members(); |
| 1437 | for (Scope.Entry e = s.elems; |
| 1438 | undef == null && e != null; |
| 1439 | e = e.sibling) { |
| 1440 | if (e.sym.kind == MTH && |
| 1441 | (e.sym.flags() & (ABSTRACT|IPROXY)) == ABSTRACT) { |
| 1442 | MethodSymbol absmeth = (MethodSymbol)e.sym; |
| 1443 | MethodSymbol implmeth = absmeth.implementation(impl, types, true); |
| 1444 | if (implmeth == null || implmeth == absmeth) |
| 1445 | undef = absmeth; |
| 1446 | } |
| 1447 | } |
| 1448 | if (undef == null) { |
| 1449 | Type st = types.supertype(c.type); |
| 1450 | if (st.tag == CLASS) |
| 1451 | undef = firstUndef(impl, (ClassSymbol)st.tsym); |
| 1452 | } |
| 1453 | for (List<Type> l = types.interfaces(c.type); |
| 1454 | undef == null && l.nonEmpty(); |
| 1455 | l = l.tail) { |
| 1456 | undef = firstUndef(impl, (ClassSymbol)l.head.tsym); |
| 1457 | } |
| 1458 | } |
| 1459 | return undef; |
| 1460 | } |
| 1461 | |
| 1462 | /** Check for cyclic references. Issue an error if the |
| 1463 | * symbol of the type referred to has a LOCKED flag set. |
| 1464 | * |
| 1465 | * @param pos Position to be used for error reporting. |
| 1466 | * @param t The type referred to. |
| 1467 | */ |
| 1468 | void checkNonCyclic(DiagnosticPosition pos, Type t) { |
| 1469 | checkNonCyclicInternal(pos, t); |
| 1470 | } |
| 1471 | |
| 1472 | |
| 1473 | void checkNonCyclic(DiagnosticPosition pos, TypeVar t) { |
| 1474 | checkNonCyclic1(pos, t, new HashSet<TypeVar>()); |
| 1475 | } |
| 1476 | |
| 1477 | private void checkNonCyclic1(DiagnosticPosition pos, Type t, Set<TypeVar> seen) { |
| 1478 | final TypeVar tv; |
| 1479 | if (seen.contains(t)) { |
| 1480 | tv = (TypeVar)t; |
| 1481 | tv.bound = new ErrorType(); |
| 1482 | log.error(pos, "cyclic.inheritance", t); |
| 1483 | } else if (t.tag == TYPEVAR) { |
| 1484 | tv = (TypeVar)t; |
| 1485 | seen.add(tv); |
| 1486 | for (Type b : types.getBounds(tv)) |
| 1487 | checkNonCyclic1(pos, b, seen); |
| 1488 | } |
| 1489 | } |
| 1490 | |
| 1491 | /** Check for cyclic references. Issue an error if the |
| 1492 | * symbol of the type referred to has a LOCKED flag set. |
| 1493 | * |
| 1494 | * @param pos Position to be used for error reporting. |
| 1495 | * @param t The type referred to. |
| 1496 | * @returns True if the check completed on all attributed classes |
| 1497 | */ |
| 1498 | private boolean checkNonCyclicInternal(DiagnosticPosition pos, Type t) { |
| 1499 | boolean complete = true; // was the check complete? |
| 1500 | //- System.err.println("checkNonCyclicInternal("+t+");");//DEBUG |
| 1501 | Symbol c = t.tsym; |
| 1502 | if ((c.flags_field & ACYCLIC) != 0) return true; |
| 1503 | |
| 1504 | if ((c.flags_field & LOCKED) != 0) { |
| 1505 | noteCyclic(pos, (ClassSymbol)c); |
| 1506 | } else if (!c.type.isErroneous()) { |
| 1507 | try { |
| 1508 | c.flags_field |= LOCKED; |
| 1509 | if (c.type.tag == CLASS) { |
| 1510 | ClassType clazz = (ClassType)c.type; |
| 1511 | if (clazz.interfaces_field != null) |
| 1512 | for (List<Type> l=clazz.interfaces_field; l.nonEmpty(); l=l.tail) |
| 1513 | complete &= checkNonCyclicInternal(pos, l.head); |
| 1514 | if (clazz.supertype_field != null) { |
| 1515 | Type st = clazz.supertype_field; |
| 1516 | if (st != null && st.tag == CLASS) |
| 1517 | complete &= checkNonCyclicInternal(pos, st); |
| 1518 | } |
| 1519 | if (c.owner.kind == TYP) |
| 1520 | complete &= checkNonCyclicInternal(pos, c.owner.type); |
| 1521 | } |
| 1522 | } finally { |
| 1523 | c.flags_field &= ~LOCKED; |
| 1524 | } |
| 1525 | } |
| 1526 | if (complete) |
| 1527 | complete = ((c.flags_field & UNATTRIBUTED) == 0) && c.completer == null; |
| 1528 | if (complete) c.flags_field |= ACYCLIC; |
| 1529 | return complete; |
| 1530 | } |
| 1531 | |
| 1532 | /** Note that we found an inheritance cycle. */ |
| 1533 | private void noteCyclic(DiagnosticPosition pos, ClassSymbol c) { |
| 1534 | log.error(pos, "cyclic.inheritance", c); |
| 1535 | for (List<Type> l=types.interfaces(c.type); l.nonEmpty(); l=l.tail) |
| 1536 | l.head = new ErrorType((ClassSymbol)l.head.tsym); |
| 1537 | Type st = types.supertype(c.type); |
| 1538 | if (st.tag == CLASS) |
| 1539 | ((ClassType)c.type).supertype_field = new ErrorType((ClassSymbol)st.tsym); |
| 1540 | c.type = new ErrorType(c); |
| 1541 | c.flags_field |= ACYCLIC; |
| 1542 | } |
| 1543 | |
| 1544 | /** Check that all methods which implement some |
| 1545 | * method conform to the method they implement. |
| 1546 | * @param tree The class definition whose members are checked. |
| 1547 | */ |
| 1548 | void checkImplementations(JCClassDecl tree) { |
| 1549 | checkImplementations(tree, tree.sym); |
| 1550 | } |
| 1551 | //where |
| 1552 | /** Check that all methods which implement some |
| 1553 | * method in `ic' conform to the method they implement. |
| 1554 | */ |
| 1555 | void checkImplementations(JCClassDecl tree, ClassSymbol ic) { |
| 1556 | ClassSymbol origin = tree.sym; |
| 1557 | for (List<Type> l = types.closure(ic.type); l.nonEmpty(); l = l.tail) { |
| 1558 | ClassSymbol lc = (ClassSymbol)l.head.tsym; |
| 1559 | if ((allowGenerics || origin != lc) && (lc.flags() & ABSTRACT) != 0) { |
| 1560 | for (Scope.Entry e=lc.members().elems; e != null; e=e.sibling) { |
| 1561 | if (e.sym.kind == MTH && |
| 1562 | (e.sym.flags() & (STATIC|ABSTRACT)) == ABSTRACT) { |
| 1563 | MethodSymbol absmeth = (MethodSymbol)e.sym; |
| 1564 | MethodSymbol implmeth = absmeth.implementation(origin, types, false); |
| 1565 | if (implmeth != null && implmeth != absmeth && |
| 1566 | (implmeth.owner.flags() & INTERFACE) == |
| 1567 | (origin.flags() & INTERFACE)) { |
| 1568 | // don't check if implmeth is in a class, yet |
| 1569 | // origin is an interface. This case arises only |
| 1570 | // if implmeth is declared in Object. The reason is |
| 1571 | // that interfaces really don't inherit from |
| 1572 | // Object it's just that the compiler represents |
| 1573 | // things that way. |
| 1574 | checkOverride(tree, implmeth, absmeth, origin); |
| 1575 | } |
| 1576 | } |
| 1577 | } |
| 1578 | } |
| 1579 | } |
| 1580 | } |
| 1581 | |
| 1582 | /** Check that all abstract methods implemented by a class are |
| 1583 | * mutually compatible. |
| 1584 | * @param pos Position to be used for error reporting. |
| 1585 | * @param c The class whose interfaces are checked. |
| 1586 | */ |
| 1587 | void checkCompatibleSupertypes(DiagnosticPosition pos, Type c) { |
| 1588 | List<Type> supertypes = types.interfaces(c); |
| 1589 | Type supertype = types.supertype(c); |
| 1590 | if (supertype.tag == CLASS && |
| 1591 | (supertype.tsym.flags() & ABSTRACT) != 0) |
| 1592 | supertypes = supertypes.prepend(supertype); |
| 1593 | for (List<Type> l = supertypes; l.nonEmpty(); l = l.tail) { |
| 1594 | if (allowGenerics && !l.head.getTypeArguments().isEmpty() && |
| 1595 | !checkCompatibleAbstracts(pos, l.head, l.head, c)) |
| 1596 | return; |
| 1597 | for (List<Type> m = supertypes; m != l; m = m.tail) |
| 1598 | if (!checkCompatibleAbstracts(pos, l.head, m.head, c)) |
| 1599 | return; |
| 1600 | } |
| 1601 | checkCompatibleConcretes(pos, c); |
| 1602 | } |
| 1603 | |
| 1604 | /** Check that class c does not implement directly or indirectly |
| 1605 | * the same parameterized interface with two different argument lists. |
| 1606 | * @param pos Position to be used for error reporting. |
| 1607 | * @param type The type whose interfaces are checked. |
| 1608 | */ |
| 1609 | void checkClassBounds(DiagnosticPosition pos, Type type) { |
| 1610 | checkClassBounds(pos, new HashMap<TypeSymbol,Type>(), type); |
| 1611 | } |
| 1612 | //where |
| 1613 | /** Enter all interfaces of type `type' into the hash table `seensofar' |
| 1614 | * with their class symbol as key and their type as value. Make |
| 1615 | * sure no class is entered with two different types. |
| 1616 | */ |
| 1617 | void checkClassBounds(DiagnosticPosition pos, |
| 1618 | Map<TypeSymbol,Type> seensofar, |
| 1619 | Type type) { |
| 1620 | if (type.isErroneous()) return; |
| 1621 | for (List<Type> l = types.interfaces(type); l.nonEmpty(); l = l.tail) { |
| 1622 | Type it = l.head; |
| 1623 | Type oldit = seensofar.put(it.tsym, it); |
| 1624 | if (oldit != null) { |
| 1625 | List<Type> oldparams = oldit.allparams(); |
| 1626 | List<Type> newparams = it.allparams(); |
| 1627 | if (!types.containsTypeEquivalent(oldparams, newparams)) |
| 1628 | log.error(pos, "cant.inherit.diff.arg", |
| 1629 | it.tsym, Type.toString(oldparams), |
| 1630 | Type.toString(newparams)); |
| 1631 | } |
| 1632 | checkClassBounds(pos, seensofar, it); |
| 1633 | } |
| 1634 | Type st = types.supertype(type); |
| 1635 | if (st != null) checkClassBounds(pos, seensofar, st); |
| 1636 | } |
| 1637 | |
| 1638 | /** Enter interface into into set. |
| 1639 | * If it existed already, issue a "repeated interface" error. |
| 1640 | */ |
| 1641 | void checkNotRepeated(DiagnosticPosition pos, Type it, Set<Type> its) { |
| 1642 | if (its.contains(it)) |
| 1643 | log.error(pos, "repeated.interface"); |
| 1644 | else { |
| 1645 | its.add(it); |
| 1646 | } |
| 1647 | } |
| 1648 | |
| 1649 | /* ************************************************************************* |
| 1650 | * Check annotations |
| 1651 | **************************************************************************/ |
| 1652 | |
| 1653 | /** Annotation types are restricted to primitives, String, an |
| 1654 | * enum, an annotation, Class, Class<?>, Class<? extends |
| 1655 | * Anything>, arrays of the preceding. |
| 1656 | */ |
| 1657 | void validateAnnotationType(JCTree restype) { |
| 1658 | // restype may be null if an error occurred, so don't bother validating it |
| 1659 | if (restype != null) { |
| 1660 | validateAnnotationType(restype.pos(), restype.type); |
| 1661 | } |
| 1662 | } |
| 1663 | |
| 1664 | void validateAnnotationType(DiagnosticPosition pos, Type type) { |
| 1665 | if (type.isPrimitive()) return; |
| 1666 | if (types.isSameType(type, syms.stringType)) return; |
| 1667 | if ((type.tsym.flags() & Flags.ENUM) != 0) return; |
| 1668 | if ((type.tsym.flags() & Flags.ANNOTATION) != 0) return; |
| 1669 | if (types.lowerBound(type).tsym == syms.classType.tsym) return; |
| 1670 | if (types.isArray(type) && !types.isArray(types.elemtype(type))) { |
| 1671 | validateAnnotationType(pos, types.elemtype(type)); |
| 1672 | return; |
| 1673 | } |
| 1674 | log.error(pos, "invalid.annotation.member.type"); |
| 1675 | } |
| 1676 | |
| 1677 | /** |
| 1678 | * "It is also a compile-time error if any method declared in an |
| 1679 | * annotation type has a signature that is override-equivalent to |
| 1680 | * that of any public or protected method declared in class Object |
| 1681 | * or in the interface annotation.Annotation." |
| 1682 | * |
| 1683 | * @jls3 9.6 Annotation Types |
| 1684 | */ |
| 1685 | void validateAnnotationMethod(DiagnosticPosition pos, MethodSymbol m) { |
| 1686 | for (Type sup = syms.annotationType; sup.tag == CLASS; sup = types.supertype(sup)) { |
| 1687 | Scope s = sup.tsym.members(); |
| 1688 | for (Scope.Entry e = s.lookup(m.name); e.scope != null; e = e.next()) { |
| 1689 | if (e.sym.kind == MTH && |
| 1690 | (e.sym.flags() & (PUBLIC | PROTECTED)) != 0 && |
| 1691 | types.overrideEquivalent(m.type, e.sym.type)) |
| 1692 | log.error(pos, "intf.annotation.member.clash", e.sym, sup); |
| 1693 | } |
| 1694 | } |
| 1695 | } |
| 1696 | |
| 1697 | /** Check the annotations of a symbol. |
| 1698 | */ |
| 1699 | public void validateAnnotations(List<JCAnnotation> annotations, Symbol s) { |
| 1700 | if (skipAnnotations) return; |
| 1701 | for (JCAnnotation a : annotations) |
| 1702 | validateAnnotation(a, s); |
| 1703 | } |
| 1704 | |
| 1705 | /** Check an annotation of a symbol. |
| 1706 | */ |
| 1707 | public void validateAnnotation(JCAnnotation a, Symbol s) { |
| 1708 | validateAnnotation(a); |
| 1709 | |
| 1710 | if (!annotationApplicable(a, s)) |
| 1711 | log.error(a.pos(), "annotation.type.not.applicable"); |
| 1712 | |
| 1713 | if (a.annotationType.type.tsym == syms.overrideType.tsym) { |
| 1714 | if (!isOverrider(s)) |
| 1715 | log.error(a.pos(), "method.does.not.override.superclass"); |
| 1716 | } |
| 1717 | } |
| 1718 | |
| 1719 | /** Is s a method symbol that overrides a method in a superclass? */ |
| 1720 | boolean isOverrider(Symbol s) { |
| 1721 | if (s.kind != MTH || s.isStatic()) |
| 1722 | return false; |
| 1723 | MethodSymbol m = (MethodSymbol)s; |
| 1724 | TypeSymbol owner = (TypeSymbol)m.owner; |
| 1725 | for (Type sup : types.closure(owner.type)) { |
| 1726 | if (sup == owner.type) |
| 1727 | continue; // skip "this" |
| 1728 | Scope scope = sup.tsym.members(); |
| 1729 | for (Scope.Entry e = scope.lookup(m.name); e.scope != null; e = e.next()) { |
| 1730 | if (!e.sym.isStatic() && m.overrides(e.sym, owner, types, true)) |
| 1731 | return true; |
| 1732 | } |
| 1733 | } |
| 1734 | return false; |
| 1735 | } |
| 1736 | |
| 1737 | /** Is the annotation applicable to the symbol? */ |
| 1738 | boolean annotationApplicable(JCAnnotation a, Symbol s) { |
| 1739 | Attribute.Compound atTarget = |
| 1740 | a.annotationType.type.tsym.attribute(syms.annotationTargetType.tsym); |
| 1741 | if (atTarget == null) return true; |
| 1742 | Attribute atValue = atTarget.member(names.value); |
| 1743 | if (!(atValue instanceof Attribute.Array)) return true; // error recovery |
| 1744 | Attribute.Array arr = (Attribute.Array) atValue; |
| 1745 | for (Attribute app : arr.values) { |
| 1746 | if (!(app instanceof Attribute.Enum)) return true; // recovery |
| 1747 | Attribute.Enum e = (Attribute.Enum) app; |
| 1748 | if (e.value.name == names.TYPE) |
| 1749 | { if (s.kind == TYP) return true; } |
| 1750 | else if (e.value.name == names.FIELD) |
| 1751 | { if (s.kind == VAR && s.owner.kind != MTH) return true; } |
| 1752 | else if (e.value.name == names.METHOD) |
| 1753 | { if (s.kind == MTH && !s.isConstructor()) return true; } |
| 1754 | else if (e.value.name == names.PARAMETER) |
| 1755 | { if (s.kind == VAR && |
| 1756 | s.owner.kind == MTH && |
| 1757 | (s.flags() & PARAMETER) != 0) |
| 1758 | return true; |
| 1759 | } |
| 1760 | else if (e.value.name == names.CONSTRUCTOR) |
| 1761 | { if (s.kind == MTH && s.isConstructor()) return true; } |
| 1762 | else if (e.value.name == names.LOCAL_VARIABLE) |
| 1763 | { if (s.kind == VAR && s.owner.kind == MTH && |
| 1764 | (s.flags() & PARAMETER) == 0) |
| 1765 | return true; |
| 1766 | } |
| 1767 | else if (e.value.name == names.ANNOTATION_TYPE) |
| 1768 | { if (s.kind == TYP && (s.flags() & ANNOTATION) != 0) |
| 1769 | return true; |
| 1770 | } |
| 1771 | else if (e.value.name == names.PACKAGE) |
| 1772 | { if (s.kind == PCK) return true; } |
| 1773 | else |
| 1774 | return true; // recovery |
| 1775 | } |
| 1776 | return false; |
| 1777 | } |
| 1778 | |
| 1779 | /** Check an annotation value. |
| 1780 | */ |
| 1781 | public void validateAnnotation(JCAnnotation a) { |
| 1782 | if (a.type.isErroneous()) return; |
| 1783 | |
| 1784 | // collect an inventory of the members |
| 1785 | Set<MethodSymbol> members = new HashSet<MethodSymbol>(); |
| 1786 | for (Scope.Entry e = a.annotationType.type.tsym.members().elems; |
| 1787 | e != null; |
| 1788 | e = e.sibling) |
| 1789 | if (e.sym.kind == MTH) |
| 1790 | members.add((MethodSymbol) e.sym); |
| 1791 | |
| 1792 | // count them off as they're annotated |
| 1793 | for (JCTree arg : a.args) { |
| 1794 | if (arg.getTag() != JCTree.ASSIGN) continue; // recovery |
| 1795 | JCAssign assign = (JCAssign) arg; |
| 1796 | Symbol m = TreeInfo.symbol(assign.lhs); |
| 1797 | if (m == null || m.type.isErroneous()) continue; |
| 1798 | if (!members.remove(m)) |
| 1799 | log.error(arg.pos(), "duplicate.annotation.member.value", |
| 1800 | m.name, a.type); |
| 1801 | if (assign.rhs.getTag() == ANNOTATION) |
| 1802 | validateAnnotation((JCAnnotation)assign.rhs); |
| 1803 | } |
| 1804 | |
| 1805 | // all the remaining ones better have default values |
| 1806 | for (MethodSymbol m : members) |
| 1807 | if (m.defaultValue == null && !m.type.isErroneous()) |
| 1808 | log.error(a.pos(), "annotation.missing.default.value", |
| 1809 | a.type, m.name); |
| 1810 | |
| 1811 | // special case: java.lang.annotation.Target must not have |
| 1812 | // repeated values in its value member |
| 1813 | if (a.annotationType.type.tsym != syms.annotationTargetType.tsym || |
| 1814 | a.args.tail == null) |
| 1815 | return; |
| 1816 | |
| 1817 | if (a.args.head.getTag() != JCTree.ASSIGN) return; // error recovery |
| 1818 | JCAssign assign = (JCAssign) a.args.head; |
| 1819 | Symbol m = TreeInfo.symbol(assign.lhs); |
| 1820 | if (m.name != names.value) return; |
| 1821 | JCTree rhs = assign.rhs; |
| 1822 | if (rhs.getTag() != JCTree.NEWARRAY) return; |
| 1823 | JCNewArray na = (JCNewArray) rhs; |
| 1824 | Set<Symbol> targets = new HashSet<Symbol>(); |
| 1825 | for (JCTree elem : na.elems) { |
| 1826 | if (!targets.add(TreeInfo.symbol(elem))) { |
| 1827 | log.error(elem.pos(), "repeated.annotation.target"); |
| 1828 | } |
| 1829 | } |
| 1830 | } |
| 1831 | |
| 1832 | void checkDeprecatedAnnotation(DiagnosticPosition pos, Symbol s) { |
| 1833 | if (allowAnnotations && |
| 1834 | lint.isEnabled(Lint.LintCategory.DEP_ANN) && |
| 1835 | (s.flags() & DEPRECATED) != 0 && |
| 1836 | !syms.deprecatedType.isErroneous() && |
| 1837 | s.attribute(syms.deprecatedType.tsym) == null) { |
| 1838 | log.warning(pos, "missing.deprecated.annotation"); |
| 1839 | } |
| 1840 | } |
| 1841 | |
| 1842 | /* ************************************************************************* |
| 1843 | * Check for recursive annotation elements. |
| 1844 | **************************************************************************/ |
| 1845 | |
| 1846 | /** Check for cycles in the graph of annotation elements. |
| 1847 | */ |
| 1848 | void checkNonCyclicElements(JCClassDecl tree) { |
| 1849 | if ((tree.sym.flags_field & ANNOTATION) == 0) return; |
| 1850 | assert (tree.sym.flags_field & LOCKED) == 0; |
| 1851 | try { |
| 1852 | tree.sym.flags_field |= LOCKED; |
| 1853 | for (JCTree def : tree.defs) { |
| 1854 | if (def.getTag() != JCTree.METHODDEF) continue; |
| 1855 | JCMethodDecl meth = (JCMethodDecl)def; |
| 1856 | checkAnnotationResType(meth.pos(), meth.restype.type); |
| 1857 | } |
| 1858 | } finally { |
| 1859 | tree.sym.flags_field &= ~LOCKED; |
| 1860 | tree.sym.flags_field |= ACYCLIC_ANN; |
| 1861 | } |
| 1862 | } |
| 1863 | |
| 1864 | void checkNonCyclicElementsInternal(DiagnosticPosition pos, TypeSymbol tsym) { |
| 1865 | if ((tsym.flags_field & ACYCLIC_ANN) != 0) |
| 1866 | return; |
| 1867 | if ((tsym.flags_field & LOCKED) != 0) { |
| 1868 | log.error(pos, "cyclic.annotation.element"); |
| 1869 | return; |
| 1870 | } |
| 1871 | try { |
| 1872 | tsym.flags_field |= LOCKED; |
| 1873 | for (Scope.Entry e = tsym.members().elems; e != null; e = e.sibling) { |
| 1874 | Symbol s = e.sym; |
| 1875 | if (s.kind != Kinds.MTH) |
| 1876 | continue; |
| 1877 | checkAnnotationResType(pos, ((MethodSymbol)s).type.getReturnType()); |
| 1878 | } |
| 1879 | } finally { |
| 1880 | tsym.flags_field &= ~LOCKED; |
| 1881 | tsym.flags_field |= ACYCLIC_ANN; |
| 1882 | } |
| 1883 | } |
| 1884 | |
| 1885 | void checkAnnotationResType(DiagnosticPosition pos, Type type) { |
| 1886 | switch (type.tag) { |
| 1887 | case TypeTags.CLASS: |
| 1888 | if ((type.tsym.flags() & ANNOTATION) != 0) |
| 1889 | checkNonCyclicElementsInternal(pos, type.tsym); |
| 1890 | break; |
| 1891 | case TypeTags.ARRAY: |
| 1892 | checkAnnotationResType(pos, types.elemtype(type)); |
| 1893 | break; |
| 1894 | default: |
| 1895 | break; // int etc |
| 1896 | } |
| 1897 | } |
| 1898 | |
| 1899 | /* ************************************************************************* |
| 1900 | * Check for cycles in the constructor call graph. |
| 1901 | **************************************************************************/ |
| 1902 | |
| 1903 | /** Check for cycles in the graph of constructors calling other |
| 1904 | * constructors. |
| 1905 | */ |
| 1906 | void checkCyclicConstructors(JCClassDecl tree) { |
| 1907 | Map<Symbol,Symbol> callMap = new HashMap<Symbol, Symbol>(); |
| 1908 | |
| 1909 | // enter each constructor this-call into the map |
| 1910 | for (List<JCTree> l = tree.defs; l.nonEmpty(); l = l.tail) { |
| 1911 | JCMethodInvocation app = TreeInfo.firstConstructorCall(l.head); |
| 1912 | if (app == null) continue; |
| 1913 | JCMethodDecl meth = (JCMethodDecl) l.head; |
| 1914 | if (TreeInfo.name(app.meth) == names._this) { |
| 1915 | callMap.put(meth.sym, TreeInfo.symbol(app.meth)); |
| 1916 | } else { |
| 1917 | meth.sym.flags_field |= ACYCLIC; |
| 1918 | } |
| 1919 | } |
| 1920 | |
| 1921 | // Check for cycles in the map |
| 1922 | Symbol[] ctors = new Symbol[0]; |
| 1923 | ctors = callMap.keySet().toArray(ctors); |
| 1924 | for (Symbol caller : ctors) { |
| 1925 | checkCyclicConstructor(tree, caller, callMap); |
| 1926 | } |
| 1927 | } |
| 1928 | |
| 1929 | /** Look in the map to see if the given constructor is part of a |
| 1930 | * call cycle. |
| 1931 | */ |
| 1932 | private void checkCyclicConstructor(JCClassDecl tree, Symbol ctor, |
| 1933 | Map<Symbol,Symbol> callMap) { |
| 1934 | if (ctor != null && (ctor.flags_field & ACYCLIC) == 0) { |
| 1935 | if ((ctor.flags_field & LOCKED) != 0) { |
| 1936 | log.error(TreeInfo.diagnosticPositionFor(ctor, tree), |
| 1937 | "recursive.ctor.invocation"); |
| 1938 | } else { |
| 1939 | ctor.flags_field |= LOCKED; |
| 1940 | checkCyclicConstructor(tree, callMap.remove(ctor), callMap); |
| 1941 | ctor.flags_field &= ~LOCKED; |
| 1942 | } |
| 1943 | ctor.flags_field |= ACYCLIC; |
| 1944 | } |
| 1945 | } |
| 1946 | |
| 1947 | /* ************************************************************************* |
| 1948 | * Miscellaneous |
| 1949 | **************************************************************************/ |
| 1950 | |
| 1951 | /** |
| 1952 | * Return the opcode of the operator but emit an error if it is an |
| 1953 | * error. |
| 1954 | * @param pos position for error reporting. |
| 1955 | * @param operator an operator |
| 1956 | * @param tag a tree tag |
| 1957 | * @param left type of left hand side |
| 1958 | * @param right type of right hand side |
| 1959 | */ |
| 1960 | int checkOperator(DiagnosticPosition pos, |
| 1961 | OperatorSymbol operator, |
| 1962 | int tag, |
| 1963 | Type left, |
| 1964 | Type right) { |
| 1965 | if (operator.opcode == ByteCodes.error) { |
| 1966 | log.error(pos, |
| 1967 | "operator.cant.be.applied", |
| 1968 | treeinfo.operatorName(tag), |
| 1969 | left + "," + right); |
| 1970 | } |
| 1971 | return operator.opcode; |
| 1972 | } |
| 1973 | |
| 1974 | |
| 1975 | /** |
| 1976 | * Check for division by integer constant zero |
| 1977 | * @param pos Position for error reporting. |
| 1978 | * @param operator The operator for the expression |
| 1979 | * @param operand The right hand operand for the expression |
| 1980 | */ |
| 1981 | void checkDivZero(DiagnosticPosition pos, Symbol operator, Type operand) { |
| 1982 | if (operand.constValue() != null |
| 1983 | && lint.isEnabled(Lint.LintCategory.DIVZERO) |
| 1984 | && operand.tag <= LONG |
| 1985 | && ((Number) (operand.constValue())).longValue() == 0) { |
| 1986 | int opc = ((OperatorSymbol)operator).opcode; |
| 1987 | if (opc == ByteCodes.idiv || opc == ByteCodes.imod |
| 1988 | || opc == ByteCodes.ldiv || opc == ByteCodes.lmod) { |
| 1989 | log.warning(pos, "div.zero"); |
| 1990 | } |
| 1991 | } |
| 1992 | } |
| 1993 | |
| 1994 | /** |
| 1995 | * Check for empty statements after if |
| 1996 | */ |
| 1997 | void checkEmptyIf(JCIf tree) { |
| 1998 | if (tree.thenpart.getTag() == JCTree.SKIP && tree.elsepart == null && lint.isEnabled(Lint.LintCategory.EMPTY)) |
| 1999 | log.warning(tree.thenpart.pos(), "empty.if"); |
| 2000 | } |
| 2001 | |
| 2002 | /** Check that symbol is unique in given scope. |
| 2003 | * @param pos Position for error reporting. |
| 2004 | * @param sym The symbol. |
| 2005 | * @param s The scope. |
| 2006 | */ |
| 2007 | boolean checkUnique(DiagnosticPosition pos, Symbol sym, Scope s) { |
| 2008 | if (sym.type.isErroneous()) |
| 2009 | return true; |
| 2010 | if (sym.owner.name == names.any) return false; |
| 2011 | for (Scope.Entry e = s.lookup(sym.name); e.scope == s; e = e.next()) { |
| 2012 | if (sym != e.sym && |
| 2013 | sym.kind == e.sym.kind && |
| 2014 | sym.name != names.error && |
| 2015 | (sym.kind != MTH || types.overrideEquivalent(sym.type, e.sym.type))) { |
| 2016 | if ((sym.flags() & VARARGS) != (e.sym.flags() & VARARGS)) |
| 2017 | varargsDuplicateError(pos, sym, e.sym); |
| 2018 | else |
| 2019 | duplicateError(pos, e.sym); |
| 2020 | return false; |
| 2021 | } |
| 2022 | } |
| 2023 | return true; |
| 2024 | } |
| 2025 | |
| 2026 | /** Check that single-type import is not already imported or top-level defined, |
| 2027 | * but make an exception for two single-type imports which denote the same type. |
| 2028 | * @param pos Position for error reporting. |
| 2029 | * @param sym The symbol. |
| 2030 | * @param s The scope |
| 2031 | */ |
| 2032 | boolean checkUniqueImport(DiagnosticPosition pos, Symbol sym, Scope s) { |
| 2033 | return checkUniqueImport(pos, sym, s, false); |
| 2034 | } |
| 2035 | |
| 2036 | /** Check that static single-type import is not already imported or top-level defined, |
| 2037 | * but make an exception for two single-type imports which denote the same type. |
| 2038 | * @param pos Position for error reporting. |
| 2039 | * @param sym The symbol. |
| 2040 | * @param s The scope |
| 2041 | * @param staticImport Whether or not this was a static import |
| 2042 | */ |
| 2043 | boolean checkUniqueStaticImport(DiagnosticPosition pos, Symbol sym, Scope s) { |
| 2044 | return checkUniqueImport(pos, sym, s, true); |
| 2045 | } |
| 2046 | |
| 2047 | /** Check that single-type import is not already imported or top-level defined, |
| 2048 | * but make an exception for two single-type imports which denote the same type. |
| 2049 | * @param pos Position for error reporting. |
| 2050 | * @param sym The symbol. |
| 2051 | * @param s The scope. |
| 2052 | * @param staticImport Whether or not this was a static import |
| 2053 | */ |
| 2054 | private boolean checkUniqueImport(DiagnosticPosition pos, Symbol sym, Scope s, boolean staticImport) { |
| 2055 | for (Scope.Entry e = s.lookup(sym.name); e.scope != null; e = e.next()) { |
| 2056 | // is encountered class entered via a class declaration? |
| 2057 | boolean isClassDecl = e.scope == s; |
| 2058 | if ((isClassDecl || sym != e.sym) && |
| 2059 | sym.kind == e.sym.kind && |
| 2060 | sym.name != names.error) { |
| 2061 | if (!e.sym.type.isErroneous()) { |
| 2062 | String what = e.sym.toString(); |
| 2063 | if (!isClassDecl) { |
| 2064 | if (staticImport) |
| 2065 | log.error(pos, "already.defined.static.single.import", what); |
| 2066 | else |
| 2067 | log.error(pos, "already.defined.single.import", what); |
| 2068 | } |
| 2069 | else if (sym != e.sym) |
| 2070 | log.error(pos, "already.defined.this.unit", what); |
| 2071 | } |
| 2072 | return false; |
| 2073 | } |
| 2074 | } |
| 2075 | return true; |
| 2076 | } |
| 2077 | |
| 2078 | /** Check that a qualified name is in canonical form (for import decls). |
| 2079 | */ |
| 2080 | public void checkCanonical(JCTree tree) { |
| 2081 | if (!isCanonical(tree)) |
| 2082 | log.error(tree.pos(), "import.requires.canonical", |
| 2083 | TreeInfo.symbol(tree)); |
| 2084 | } |
| 2085 | // where |
| 2086 | private boolean isCanonical(JCTree tree) { |
| 2087 | while (tree.getTag() == JCTree.SELECT) { |
| 2088 | JCFieldAccess s = (JCFieldAccess) tree; |
| 2089 | if (s.sym.owner != TreeInfo.symbol(s.selected)) |
| 2090 | return false; |
| 2091 | tree = s.selected; |
| 2092 | } |
| 2093 | return true; |
| 2094 | } |
| 2095 | |
| 2096 | private class ConversionWarner extends Warner { |
| 2097 | final String key; |
| 2098 | final Type found; |
| 2099 | final Type expected; |
| 2100 | public ConversionWarner(DiagnosticPosition pos, String key, Type found, Type expected) { |
| 2101 | super(pos); |
| 2102 | this.key = key; |
| 2103 | this.found = found; |
| 2104 | this.expected = expected; |
| 2105 | } |
| 2106 | |
| 2107 | public void warnUnchecked() { |
| 2108 | boolean warned = this.warned; |
| 2109 | super.warnUnchecked(); |
| 2110 | if (warned) return; // suppress redundant diagnostics |
| 2111 | Object problem = JCDiagnostic.fragment(key); |
| 2112 | Check.this.warnUnchecked(pos(), "prob.found.req", problem, found, expected); |
| 2113 | } |
| 2114 | } |
| 2115 | |
| 2116 | public Warner castWarner(DiagnosticPosition pos, Type found, Type expected) { |
| 2117 | return new ConversionWarner(pos, "unchecked.cast.to.type", found, expected); |
| 2118 | } |
| 2119 | |
| 2120 | public Warner convertWarner(DiagnosticPosition pos, Type found, Type expected) { |
| 2121 | return new ConversionWarner(pos, "unchecked.assign", found, expected); |
| 2122 | } |
| 2123 | } |