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 com.sun.tools.javac.api.Formattable.LocalizedString; 29 import com.sun.tools.javac.code.*; 30 import com.sun.tools.javac.code.Scope.WriteableScope; 31 import com.sun.tools.javac.code.Source.Feature; 32 import com.sun.tools.javac.code.Symbol.*; 33 import com.sun.tools.javac.code.Type.*; 34 import com.sun.tools.javac.comp.Attr.ResultInfo; 35 import com.sun.tools.javac.comp.Check.CheckContext; 36 import com.sun.tools.javac.comp.DeferredAttr.AttrMode; 37 import com.sun.tools.javac.comp.DeferredAttr.DeferredAttrContext; 38 import com.sun.tools.javac.comp.DeferredAttr.DeferredType; 39 import com.sun.tools.javac.comp.Resolve.MethodResolutionContext.Candidate; 40 import com.sun.tools.javac.comp.Resolve.MethodResolutionDiagHelper.Template; 41 import com.sun.tools.javac.comp.Resolve.ReferenceLookupResult.StaticKind; 42 import com.sun.tools.javac.jvm.*; 43 import com.sun.tools.javac.main.Option; 44 import com.sun.tools.javac.resources.CompilerProperties.Errors; 45 import com.sun.tools.javac.resources.CompilerProperties.Fragments; 46 import com.sun.tools.javac.resources.CompilerProperties.Warnings; 47 import com.sun.tools.javac.tree.*; 48 import com.sun.tools.javac.tree.JCTree.*; 49 import com.sun.tools.javac.tree.JCTree.JCMemberReference.ReferenceKind; 50 import com.sun.tools.javac.tree.JCTree.JCPolyExpression.*; 51 import com.sun.tools.javac.util.*; 52 import com.sun.tools.javac.util.DefinedBy.Api; 53 import com.sun.tools.javac.util.JCDiagnostic.DiagnosticFlag; 54 import com.sun.tools.javac.util.JCDiagnostic.DiagnosticPosition; 55 import com.sun.tools.javac.util.JCDiagnostic.DiagnosticType; 56 57 import java.util.Arrays; 58 import java.util.Collection; 59 import java.util.EnumSet; 60 import java.util.HashSet; 61 import java.util.Iterator; 62 import java.util.LinkedHashMap; 63 import java.util.Map; 64 import java.util.Set; 65 import java.util.function.BiFunction; 66 import java.util.function.BiPredicate; 67 import java.util.function.Function; 68 import java.util.function.Predicate; 69 import java.util.function.UnaryOperator; 70 import java.util.stream.Stream; 71 import java.util.stream.StreamSupport; 72 73 import javax.lang.model.element.ElementVisitor; 74 75 import static com.sun.tools.javac.code.Flags.*; 76 import static com.sun.tools.javac.code.Flags.BLOCK; 77 import static com.sun.tools.javac.code.Flags.STATIC; 78 import static com.sun.tools.javac.code.Kinds.*; 79 import static com.sun.tools.javac.code.Kinds.Kind.*; 80 import static com.sun.tools.javac.code.TypeTag.*; 81 import static com.sun.tools.javac.comp.Resolve.MethodResolutionPhase.*; 82 import static com.sun.tools.javac.tree.JCTree.Tag.*; 83 import static com.sun.tools.javac.util.Iterators.createCompoundIterator; 84 85 /** Helper class for name resolution, used mostly by the attribution phase. 86 * 87 * <p><b>This is NOT part of any supported API. 88 * If you write code that depends on this, you do so at your own risk. 89 * This code and its internal interfaces are subject to change or 90 * deletion without notice.</b> 91 */ 92 public class Resolve { 93 protected static final Context.Key<Resolve> resolveKey = new Context.Key<>(); 94 95 Names names; 96 Log log; 97 Symtab syms; 98 Attr attr; 99 AttrRecover attrRecover; 100 DeferredAttr deferredAttr; 101 Check chk; 102 Infer infer; 103 ClassFinder finder; 104 ModuleFinder moduleFinder; 105 Types types; 106 JCDiagnostic.Factory diags; 107 public final boolean allowModules; 108 public final boolean allowRecords; 109 public final boolean allowValueClasses; 110 private final boolean compactMethodDiags; 111 private final boolean allowLocalVariableTypeInference; 112 private final boolean allowYieldStatement; 113 final EnumSet<VerboseResolutionMode> verboseResolutionMode; 114 final boolean dumpMethodReferenceSearchResults; 115 final boolean allowPrimitiveClasses; 116 117 WriteableScope polymorphicSignatureScope; 118 119 protected Resolve(Context context) { 120 context.put(resolveKey, this); 121 syms = Symtab.instance(context); 122 123 varNotFound = new SymbolNotFoundError(ABSENT_VAR); 124 methodNotFound = new SymbolNotFoundError(ABSENT_MTH); 125 typeNotFound = new SymbolNotFoundError(ABSENT_TYP); 126 referenceNotFound = ReferenceLookupResult.error(methodNotFound); 127 128 names = Names.instance(context); 129 log = Log.instance(context); 130 attr = Attr.instance(context); 131 attrRecover = AttrRecover.instance(context); 132 deferredAttr = DeferredAttr.instance(context); 133 chk = Check.instance(context); 134 infer = Infer.instance(context); 135 finder = ClassFinder.instance(context); 136 moduleFinder = ModuleFinder.instance(context); 137 types = Types.instance(context); 138 diags = JCDiagnostic.Factory.instance(context); 139 Preview preview = Preview.instance(context); 140 Source source = Source.instance(context); 141 Options options = Options.instance(context); 142 compactMethodDiags = options.isSet(Option.XDIAGS, "compact") || 143 options.isUnset(Option.XDIAGS) && options.isUnset("rawDiagnostics"); 144 verboseResolutionMode = VerboseResolutionMode.getVerboseResolutionMode(options); 145 Target target = Target.instance(context); 146 allowLocalVariableTypeInference = Feature.LOCAL_VARIABLE_TYPE_INFERENCE.allowedInSource(source); 147 allowYieldStatement = Feature.SWITCH_EXPRESSION.allowedInSource(source); 148 polymorphicSignatureScope = WriteableScope.create(syms.noSymbol); 149 allowModules = Feature.MODULES.allowedInSource(source); 150 allowRecords = Feature.RECORDS.allowedInSource(source); 151 dumpMethodReferenceSearchResults = options.isSet("debug.dumpMethodReferenceSearchResults"); 152 allowValueClasses = Feature.VALUE_CLASSES.allowedInSource(source); 153 allowPrimitiveClasses = Feature.PRIMITIVE_CLASSES.allowedInSource(source) && options.isSet("enablePrimitiveClasses"); 154 } 155 156 /** error symbols, which are returned when resolution fails 157 */ 158 private final SymbolNotFoundError varNotFound; 159 private final SymbolNotFoundError methodNotFound; 160 private final SymbolNotFoundError typeNotFound; 161 162 /** empty reference lookup result */ 163 private final ReferenceLookupResult referenceNotFound; 164 165 public static Resolve instance(Context context) { 166 Resolve instance = context.get(resolveKey); 167 if (instance == null) 168 instance = new Resolve(context); 169 return instance; 170 } 171 172 private static Symbol bestOf(Symbol s1, 173 Symbol s2) { 174 return s1.kind.betterThan(s2.kind) ? s1 : s2; 175 } 176 177 // <editor-fold defaultstate="collapsed" desc="Verbose resolution diagnostics support"> 178 enum VerboseResolutionMode { 179 SUCCESS("success"), 180 FAILURE("failure"), 181 APPLICABLE("applicable"), 182 INAPPLICABLE("inapplicable"), 183 DEFERRED_INST("deferred-inference"), 184 PREDEF("predef"), 185 OBJECT_INIT("object-init"), 186 INTERNAL("internal"); 187 188 final String opt; 189 190 private VerboseResolutionMode(String opt) { 191 this.opt = opt; 192 } 193 194 static EnumSet<VerboseResolutionMode> getVerboseResolutionMode(Options opts) { 195 String s = opts.get("debug.verboseResolution"); 196 EnumSet<VerboseResolutionMode> res = EnumSet.noneOf(VerboseResolutionMode.class); 197 if (s == null) return res; 198 if (s.contains("all")) { 199 res = EnumSet.allOf(VerboseResolutionMode.class); 200 } 201 Collection<String> args = Arrays.asList(s.split(",")); 202 for (VerboseResolutionMode mode : values()) { 203 if (args.contains(mode.opt)) { 204 res.add(mode); 205 } else if (args.contains("-" + mode.opt)) { 206 res.remove(mode); 207 } 208 } 209 return res; 210 } 211 } 212 213 void reportVerboseResolutionDiagnostic(DiagnosticPosition dpos, Name name, Type site, 214 List<Type> argtypes, List<Type> typeargtypes, Symbol bestSoFar) { 215 boolean success = !bestSoFar.kind.isResolutionError(); 216 217 if (success && !verboseResolutionMode.contains(VerboseResolutionMode.SUCCESS)) { 218 return; 219 } else if (!success && !verboseResolutionMode.contains(VerboseResolutionMode.FAILURE)) { 220 return; 221 } 222 223 if (names.isInitOrVNew(bestSoFar.name) && 224 bestSoFar.owner == syms.objectType.tsym && 225 !verboseResolutionMode.contains(VerboseResolutionMode.OBJECT_INIT)) { 226 return; //skip diags for Object constructor resolution 227 } else if (site == syms.predefClass.type && 228 !verboseResolutionMode.contains(VerboseResolutionMode.PREDEF)) { 229 return; //skip spurious diags for predef symbols (i.e. operators) 230 } else if (currentResolutionContext.internalResolution && 231 !verboseResolutionMode.contains(VerboseResolutionMode.INTERNAL)) { 232 return; 233 } 234 235 int pos = 0; 236 int mostSpecificPos = -1; 237 ListBuffer<JCDiagnostic> subDiags = new ListBuffer<>(); 238 for (Candidate c : currentResolutionContext.candidates) { 239 if (currentResolutionContext.step != c.step || 240 (c.isApplicable() && !verboseResolutionMode.contains(VerboseResolutionMode.APPLICABLE)) || 241 (!c.isApplicable() && !verboseResolutionMode.contains(VerboseResolutionMode.INAPPLICABLE))) { 242 continue; 243 } else { 244 subDiags.append(c.isApplicable() ? 245 getVerboseApplicableCandidateDiag(pos, c.sym, c.mtype) : 246 getVerboseInapplicableCandidateDiag(pos, c.sym, c.details)); 247 if (c.sym == bestSoFar) 248 mostSpecificPos = pos; 249 pos++; 250 } 251 } 252 String key = success ? "verbose.resolve.multi" : "verbose.resolve.multi.1"; 253 List<Type> argtypes2 = argtypes.map(deferredAttr.new RecoveryDeferredTypeMap(AttrMode.SPECULATIVE, bestSoFar, currentResolutionContext.step)); 254 JCDiagnostic main = diags.note(log.currentSource(), dpos, key, name, 255 site.tsym, mostSpecificPos, currentResolutionContext.step, 256 methodArguments(argtypes2), 257 methodArguments(typeargtypes)); 258 JCDiagnostic d = new JCDiagnostic.MultilineDiagnostic(main, subDiags.toList()); 259 log.report(d); 260 } 261 262 JCDiagnostic getVerboseApplicableCandidateDiag(int pos, Symbol sym, Type inst) { 263 JCDiagnostic subDiag = null; 264 if (sym.type.hasTag(FORALL)) { 265 subDiag = diags.fragment(Fragments.PartialInstSig(inst)); 266 } 267 268 String key = subDiag == null ? 269 "applicable.method.found" : 270 "applicable.method.found.1"; 271 272 return diags.fragment(key, pos, sym, subDiag); 273 } 274 275 JCDiagnostic getVerboseInapplicableCandidateDiag(int pos, Symbol sym, JCDiagnostic subDiag) { 276 return diags.fragment(Fragments.NotApplicableMethodFound(pos, sym, subDiag)); 277 } 278 // </editor-fold> 279 280 /* ************************************************************************ 281 * Identifier resolution 282 *************************************************************************/ 283 284 /** An environment is "static" if its static level is greater than 285 * the one of its outer environment 286 */ 287 protected static boolean isStatic(Env<AttrContext> env) { 288 return env.outer != null && env.info.staticLevel > env.outer.info.staticLevel; 289 } 290 291 /** An environment is an "initializer" if it is a constructor or 292 * an instance initializer. 293 */ 294 static boolean isInitializer(Env<AttrContext> env) { 295 Symbol owner = env.info.scope.owner; 296 return owner.isInitOrVNew() || 297 owner.owner.kind == TYP && 298 (owner.kind == VAR || 299 owner.kind == MTH && (owner.flags() & BLOCK) != 0) && 300 (owner.flags() & STATIC) == 0; 301 } 302 303 /** Is class accessible in given environment? 304 * @param env The current environment. 305 * @param c The class whose accessibility is checked. 306 */ 307 public boolean isAccessible(Env<AttrContext> env, TypeSymbol c) { 308 return isAccessible(env, c, false); 309 } 310 311 public boolean isAccessible(Env<AttrContext> env, TypeSymbol c, boolean checkInner) { 312 313 /* 15.9.5.1: Note that it is possible for the signature of the anonymous constructor 314 to refer to an inaccessible type 315 */ 316 if (env.enclMethod != null && (env.enclMethod.mods.flags & ANONCONSTR) != 0) 317 return true; 318 319 if (env.info.visitingServiceImplementation && 320 env.toplevel.modle == c.packge().modle) { 321 return true; 322 } 323 324 boolean isAccessible = false; 325 switch ((short)(c.flags() & AccessFlags)) { 326 case PRIVATE: 327 isAccessible = 328 env.enclClass.sym.outermostClass() == 329 c.owner.outermostClass(); 330 break; 331 case 0: 332 isAccessible = 333 env.toplevel.packge == c.owner // fast special case 334 || 335 env.toplevel.packge == c.packge(); 336 break; 337 default: // error recovery 338 isAccessible = true; 339 break; 340 case PUBLIC: 341 if (allowModules) { 342 ModuleSymbol currModule = env.toplevel.modle; 343 currModule.complete(); 344 PackageSymbol p = c.packge(); 345 isAccessible = 346 currModule == p.modle || 347 currModule.visiblePackages.get(p.fullname) == p || 348 p == syms.rootPackage || 349 (p.modle == syms.unnamedModule && currModule.readModules.contains(p.modle)); 350 } else { 351 isAccessible = true; 352 } 353 break; 354 case PROTECTED: 355 isAccessible = 356 env.toplevel.packge == c.owner // fast special case 357 || 358 env.toplevel.packge == c.packge() 359 || 360 isInnerSubClass(env.enclClass.sym, c.owner) 361 || 362 env.info.allowProtectedAccess; 363 break; 364 } 365 return (checkInner == false || c.type.getEnclosingType() == Type.noType) ? 366 isAccessible : 367 isAccessible && isAccessible(env, c.type.getEnclosingType(), checkInner); 368 } 369 //where 370 /** Is given class a subclass of given base class, or an inner class 371 * of a subclass? 372 * Return null if no such class exists. 373 * @param c The class which is the subclass or is contained in it. 374 * @param base The base class 375 */ 376 private boolean isInnerSubClass(ClassSymbol c, Symbol base) { 377 while (c != null && !c.isSubClass(base, types)) { 378 c = c.owner.enclClass(); 379 } 380 return c != null; 381 } 382 383 boolean isAccessible(Env<AttrContext> env, Type t) { 384 return isAccessible(env, t, false); 385 } 386 387 boolean isAccessible(Env<AttrContext> env, Type t, boolean checkInner) { 388 if (t.hasTag(ARRAY)) { 389 return isAccessible(env, types.cvarUpperBound(types.elemtype(t))); 390 } else if (t.isUnion()) { 391 return StreamSupport.stream(((UnionClassType) t).getAlternativeTypes().spliterator(), false) 392 .allMatch(alternative -> isAccessible(env, alternative.tsym, checkInner)); 393 } else { 394 return isAccessible(env, t.tsym, checkInner); 395 } 396 } 397 398 /** Is symbol accessible as a member of given type in given environment? 399 * @param env The current environment. 400 * @param site The type of which the tested symbol is regarded 401 * as a member. 402 * @param sym The symbol. 403 */ 404 public boolean isAccessible(Env<AttrContext> env, Type site, Symbol sym) { 405 return isAccessible(env, site, sym, false); 406 } 407 public boolean isAccessible(Env<AttrContext> env, Type site, Symbol sym, boolean checkInner) { 408 if (names.isInitOrVNew(sym.name) && sym.owner != site.tsym) return false; 409 410 /* 15.9.5.1: Note that it is possible for the signature of the anonymous constructor 411 to refer to an inaccessible type 412 */ 413 if (env.enclMethod != null && (env.enclMethod.mods.flags & ANONCONSTR) != 0) 414 return true; 415 416 if (env.info.visitingServiceImplementation && 417 env.toplevel.modle == sym.packge().modle) { 418 return true; 419 } 420 421 ClassSymbol enclosingCsym = env.enclClass.sym; 422 if (allowPrimitiveClasses) { 423 if (sym.kind == MTH || sym.kind == VAR) { 424 /* If any primitive class types are involved, ask the same question in the reference universe, 425 where the hierarchy is navigable 426 */ 427 if (site.isPrimitiveClass()) 428 site = site.referenceProjection(); 429 } else if (sym.kind == TYP) { 430 // A type is accessible in a reference projection if it was 431 // accessible in the value projection. 432 if (site.isReferenceProjection()) 433 site = site.valueProjection(); 434 } 435 } 436 try { 437 switch ((short)(sym.flags() & AccessFlags)) { 438 case PRIVATE: 439 return 440 (env.enclClass.sym == sym.owner // fast special case 441 || 442 env.enclClass.sym.outermostClass() == 443 sym.owner.outermostClass()) 444 && 445 sym.isInheritedIn(site.tsym, types); 446 case 0: 447 return 448 (env.toplevel.packge == sym.owner.owner // fast special case 449 || 450 env.toplevel.packge == sym.packge()) 451 && 452 isAccessible(env, site, checkInner) 453 && 454 sym.isInheritedIn(site.tsym, types) 455 && 456 notOverriddenIn(site, sym); 457 case PROTECTED: 458 return 459 (env.toplevel.packge == sym.owner.owner // fast special case 460 || 461 env.toplevel.packge == sym.packge() 462 || 463 isProtectedAccessible(sym, env.enclClass.sym, site) 464 || 465 // OK to select instance method or field from 'super' or type name 466 // (but type names should be disallowed elsewhere!) 467 env.info.selectSuper && (sym.flags() & STATIC) == 0 && sym.kind != TYP) 468 && 469 isAccessible(env, site, checkInner) 470 && 471 notOverriddenIn(site, sym); 472 default: // this case includes erroneous combinations as well 473 return isAccessible(env, site, checkInner) && notOverriddenIn(site, sym); 474 } 475 } finally { 476 env.enclClass.sym = enclosingCsym; 477 } 478 } 479 //where 480 /* `sym' is accessible only if not overridden by 481 * another symbol which is a member of `site' 482 * (because, if it is overridden, `sym' is not strictly 483 * speaking a member of `site'). A polymorphic signature method 484 * cannot be overridden (e.g. MH.invokeExact(Object[])). 485 */ 486 private boolean notOverriddenIn(Type site, Symbol sym) { 487 if (sym.kind != MTH || sym.isInitOrVNew() || sym.isStatic()) 488 return true; 489 490 /* If any primitive class types are involved, ask the same question in the reference universe, 491 where the hierarchy is navigable 492 */ 493 if (allowPrimitiveClasses && site.isPrimitiveClass()) { 494 site = site.referenceProjection(); 495 } 496 497 Symbol s2 = ((MethodSymbol)sym).implementation(site.tsym, types, true); 498 return (s2 == null || s2 == sym || sym.owner == s2.owner || (sym.owner.isInterface() && s2.owner == syms.objectType.tsym) || 499 !types.isSubSignature(types.memberType(site, s2), types.memberType(site, sym))); 500 } 501 //where 502 /** Is given protected symbol accessible if it is selected from given site 503 * and the selection takes place in given class? 504 * @param sym The symbol with protected access 505 * @param c The class where the access takes place 506 * @site The type of the qualifier 507 */ 508 private 509 boolean isProtectedAccessible(Symbol sym, ClassSymbol c, Type site) { 510 Type newSite = site.hasTag(TYPEVAR) ? site.getUpperBound() : site; 511 while (c != null && 512 !(c.isSubClass(sym.owner, types) && 513 (c.flags() & INTERFACE) == 0 && 514 // In JLS 2e 6.6.2.1, the subclass restriction applies 515 // only to instance fields and methods -- types are excluded 516 // regardless of whether they are declared 'static' or not. 517 ((sym.flags() & STATIC) != 0 || sym.kind == TYP || newSite.tsym.isSubClass(c, types)))) 518 c = c.owner.enclClass(); 519 return c != null; 520 } 521 522 /** 523 * Performs a recursive scan of a type looking for accessibility problems 524 * from current attribution environment 525 */ 526 void checkAccessibleType(Env<AttrContext> env, Type t) { 527 accessibilityChecker.visit(t, env); 528 } 529 530 /** 531 * Accessibility type-visitor 532 */ 533 Types.SimpleVisitor<Void, Env<AttrContext>> accessibilityChecker = 534 new Types.SimpleVisitor<Void, Env<AttrContext>>() { 535 536 void visit(List<Type> ts, Env<AttrContext> env) { 537 for (Type t : ts) { 538 visit(t, env); 539 } 540 } 541 542 public Void visitType(Type t, Env<AttrContext> env) { 543 return null; 544 } 545 546 @Override 547 public Void visitArrayType(ArrayType t, Env<AttrContext> env) { 548 visit(t.elemtype, env); 549 return null; 550 } 551 552 @Override 553 public Void visitClassType(ClassType t, Env<AttrContext> env) { 554 visit(t.getTypeArguments(), env); 555 if (!isAccessible(env, t, true)) { 556 accessBase(new AccessError(env, null, t.tsym), env.tree.pos(), env.enclClass.sym, t, t.tsym.name, true); 557 } 558 return null; 559 } 560 561 @Override 562 public Void visitWildcardType(WildcardType t, Env<AttrContext> env) { 563 visit(t.type, env); 564 return null; 565 } 566 567 @Override 568 public Void visitMethodType(MethodType t, Env<AttrContext> env) { 569 visit(t.getParameterTypes(), env); 570 visit(t.getReturnType(), env); 571 visit(t.getThrownTypes(), env); 572 return null; 573 } 574 }; 575 576 /** Try to instantiate the type of a method so that it fits 577 * given type arguments and argument types. If successful, return 578 * the method's instantiated type, else return null. 579 * The instantiation will take into account an additional leading 580 * formal parameter if the method is an instance method seen as a member 581 * of an under determined site. In this case, we treat site as an additional 582 * parameter and the parameters of the class containing the method as 583 * additional type variables that get instantiated. 584 * 585 * @param env The current environment 586 * @param site The type of which the method is a member. 587 * @param m The method symbol. 588 * @param argtypes The invocation's given value arguments. 589 * @param typeargtypes The invocation's given type arguments. 590 * @param allowBoxing Allow boxing conversions of arguments. 591 * @param useVarargs Box trailing arguments into an array for varargs. 592 */ 593 Type rawInstantiate(Env<AttrContext> env, 594 Type site, 595 Symbol m, 596 ResultInfo resultInfo, 597 List<Type> argtypes, 598 List<Type> typeargtypes, 599 boolean allowBoxing, 600 boolean useVarargs, 601 Warner warn) throws Infer.InferenceException { 602 Type mt = types.memberType(site, m); 603 // tvars is the list of formal type variables for which type arguments 604 // need to inferred. 605 List<Type> tvars = List.nil(); 606 if (typeargtypes == null) typeargtypes = List.nil(); 607 if (!mt.hasTag(FORALL) && typeargtypes.nonEmpty()) { 608 // This is not a polymorphic method, but typeargs are supplied 609 // which is fine, see JLS 15.12.2.1 610 } else if (mt.hasTag(FORALL) && typeargtypes.nonEmpty()) { 611 ForAll pmt = (ForAll) mt; 612 if (typeargtypes.length() != pmt.tvars.length()) 613 // not enough args 614 throw new InapplicableMethodException(diags.fragment(Fragments.WrongNumberTypeArgs(Integer.toString(pmt.tvars.length())))); 615 // Check type arguments are within bounds 616 List<Type> formals = pmt.tvars; 617 List<Type> actuals = typeargtypes; 618 while (formals.nonEmpty() && actuals.nonEmpty()) { 619 List<Type> bounds = types.subst(types.getBounds((TypeVar)formals.head), 620 pmt.tvars, typeargtypes); 621 for (; bounds.nonEmpty(); bounds = bounds.tail) { 622 if (!types.isSubtypeUnchecked(actuals.head, bounds.head, warn)) { 623 throw new InapplicableMethodException(diags.fragment(Fragments.ExplicitParamDoNotConformToBounds(actuals.head, bounds))); 624 } 625 } 626 formals = formals.tail; 627 actuals = actuals.tail; 628 } 629 mt = types.subst(pmt.qtype, pmt.tvars, typeargtypes); 630 } else if (mt.hasTag(FORALL)) { 631 ForAll pmt = (ForAll) mt; 632 List<Type> tvars1 = types.newInstances(pmt.tvars); 633 tvars = tvars.appendList(tvars1); 634 mt = types.subst(pmt.qtype, pmt.tvars, tvars1); 635 } 636 637 // find out whether we need to go the slow route via infer 638 boolean instNeeded = tvars.tail != null; /*inlined: tvars.nonEmpty()*/ 639 for (List<Type> l = argtypes; 640 l.tail != null/*inlined: l.nonEmpty()*/ && !instNeeded; 641 l = l.tail) { 642 if (l.head.hasTag(FORALL)) instNeeded = true; 643 } 644 645 if (instNeeded) { 646 return infer.instantiateMethod(env, 647 tvars, 648 (MethodType)mt, 649 resultInfo, 650 (MethodSymbol)m, 651 argtypes, 652 allowBoxing, 653 useVarargs, 654 currentResolutionContext, 655 warn); 656 } 657 658 DeferredAttr.DeferredAttrContext dc = currentResolutionContext.deferredAttrContext(m, infer.emptyContext, resultInfo, warn); 659 currentResolutionContext.methodCheck.argumentsAcceptable(env, dc, 660 argtypes, mt.getParameterTypes(), warn); 661 dc.complete(); 662 return mt; 663 } 664 665 Type checkMethod(Env<AttrContext> env, 666 Type site, 667 Symbol m, 668 ResultInfo resultInfo, 669 List<Type> argtypes, 670 List<Type> typeargtypes, 671 Warner warn) { 672 MethodResolutionContext prevContext = currentResolutionContext; 673 try { 674 currentResolutionContext = new MethodResolutionContext(); 675 currentResolutionContext.attrMode = (resultInfo.pt == Infer.anyPoly) ? 676 AttrMode.SPECULATIVE : DeferredAttr.AttrMode.CHECK; 677 if (env.tree.hasTag(JCTree.Tag.REFERENCE)) { 678 //method/constructor references need special check class 679 //to handle inference variables in 'argtypes' (might happen 680 //during an unsticking round) 681 currentResolutionContext.methodCheck = 682 new MethodReferenceCheck(resultInfo.checkContext.inferenceContext()); 683 } 684 MethodResolutionPhase step = currentResolutionContext.step = env.info.pendingResolutionPhase; 685 return rawInstantiate(env, site, m, resultInfo, argtypes, typeargtypes, 686 step.isBoxingRequired(), step.isVarargsRequired(), warn); 687 } 688 finally { 689 currentResolutionContext = prevContext; 690 } 691 } 692 693 /** Same but returns null instead throwing a NoInstanceException 694 */ 695 Type instantiate(Env<AttrContext> env, 696 Type site, 697 Symbol m, 698 ResultInfo resultInfo, 699 List<Type> argtypes, 700 List<Type> typeargtypes, 701 boolean allowBoxing, 702 boolean useVarargs, 703 Warner warn) { 704 try { 705 return rawInstantiate(env, site, m, resultInfo, argtypes, typeargtypes, 706 allowBoxing, useVarargs, warn); 707 } catch (InapplicableMethodException ex) { 708 return null; 709 } 710 } 711 712 /** 713 * This interface defines an entry point that should be used to perform a 714 * method check. A method check usually consist in determining as to whether 715 * a set of types (actuals) is compatible with another set of types (formals). 716 * Since the notion of compatibility can vary depending on the circumstances, 717 * this interfaces allows to easily add new pluggable method check routines. 718 */ 719 interface MethodCheck { 720 /** 721 * Main method check routine. A method check usually consist in determining 722 * as to whether a set of types (actuals) is compatible with another set of 723 * types (formals). If an incompatibility is found, an unchecked exception 724 * is assumed to be thrown. 725 */ 726 void argumentsAcceptable(Env<AttrContext> env, 727 DeferredAttrContext deferredAttrContext, 728 List<Type> argtypes, 729 List<Type> formals, 730 Warner warn); 731 732 /** 733 * Retrieve the method check object that will be used during a 734 * most specific check. 735 */ 736 MethodCheck mostSpecificCheck(List<Type> actuals); 737 } 738 739 /** 740 * Helper enum defining all method check diagnostics (used by resolveMethodCheck). 741 */ 742 enum MethodCheckDiag { 743 /** 744 * Actuals and formals differs in length. 745 */ 746 ARITY_MISMATCH("arg.length.mismatch", "infer.arg.length.mismatch"), 747 /** 748 * An actual is incompatible with a formal. 749 */ 750 ARG_MISMATCH("no.conforming.assignment.exists", "infer.no.conforming.assignment.exists"), 751 /** 752 * An actual is incompatible with the varargs element type. 753 */ 754 VARARG_MISMATCH("varargs.argument.mismatch", "infer.varargs.argument.mismatch"), 755 /** 756 * The varargs element type is inaccessible. 757 */ 758 INACCESSIBLE_VARARGS("inaccessible.varargs.type", "inaccessible.varargs.type"); 759 760 final String basicKey; 761 final String inferKey; 762 763 MethodCheckDiag(String basicKey, String inferKey) { 764 this.basicKey = basicKey; 765 this.inferKey = inferKey; 766 } 767 768 String regex() { 769 return String.format("([a-z]*\\.)*(%s|%s)", basicKey, inferKey); 770 } 771 } 772 773 /** 774 * Dummy method check object. All methods are deemed applicable, regardless 775 * of their formal parameter types. 776 */ 777 MethodCheck nilMethodCheck = new MethodCheck() { 778 public void argumentsAcceptable(Env<AttrContext> env, DeferredAttrContext deferredAttrContext, List<Type> argtypes, List<Type> formals, Warner warn) { 779 //do nothing - method always applicable regardless of actuals 780 } 781 782 public MethodCheck mostSpecificCheck(List<Type> actuals) { 783 return this; 784 } 785 }; 786 787 /** 788 * Base class for 'real' method checks. The class defines the logic for 789 * iterating through formals and actuals and provides and entry point 790 * that can be used by subclasses in order to define the actual check logic. 791 */ 792 abstract class AbstractMethodCheck implements MethodCheck { 793 @Override 794 public void argumentsAcceptable(final Env<AttrContext> env, 795 DeferredAttrContext deferredAttrContext, 796 List<Type> argtypes, 797 List<Type> formals, 798 Warner warn) { 799 //should we expand formals? 800 boolean useVarargs = deferredAttrContext.phase.isVarargsRequired(); 801 JCTree callTree = treeForDiagnostics(env); 802 List<JCExpression> trees = TreeInfo.args(callTree); 803 804 //inference context used during this method check 805 InferenceContext inferenceContext = deferredAttrContext.inferenceContext; 806 807 Type varargsFormal = useVarargs ? formals.last() : null; 808 809 if (varargsFormal == null && 810 argtypes.size() != formals.size()) { 811 reportMC(callTree, MethodCheckDiag.ARITY_MISMATCH, inferenceContext); // not enough args 812 } 813 814 while (argtypes.nonEmpty() && formals.head != varargsFormal) { 815 DiagnosticPosition pos = trees != null ? trees.head : null; 816 checkArg(pos, false, argtypes.head, formals.head, deferredAttrContext, warn); 817 argtypes = argtypes.tail; 818 formals = formals.tail; 819 trees = trees != null ? trees.tail : trees; 820 } 821 822 if (formals.head != varargsFormal) { 823 reportMC(callTree, MethodCheckDiag.ARITY_MISMATCH, inferenceContext); // not enough args 824 } 825 826 if (useVarargs) { 827 //note: if applicability check is triggered by most specific test, 828 //the last argument of a varargs is _not_ an array type (see JLS 15.12.2.5) 829 final Type elt = types.elemtype(varargsFormal); 830 while (argtypes.nonEmpty()) { 831 DiagnosticPosition pos = trees != null ? trees.head : null; 832 checkArg(pos, true, argtypes.head, elt, deferredAttrContext, warn); 833 argtypes = argtypes.tail; 834 trees = trees != null ? trees.tail : trees; 835 } 836 } 837 } 838 839 // where 840 private JCTree treeForDiagnostics(Env<AttrContext> env) { 841 return env.info.preferredTreeForDiagnostics != null ? env.info.preferredTreeForDiagnostics : env.tree; 842 } 843 844 /** 845 * Does the actual argument conforms to the corresponding formal? 846 */ 847 abstract void checkArg(DiagnosticPosition pos, boolean varargs, Type actual, Type formal, DeferredAttrContext deferredAttrContext, Warner warn); 848 849 protected void reportMC(DiagnosticPosition pos, MethodCheckDiag diag, InferenceContext inferenceContext, Object... args) { 850 boolean inferDiag = inferenceContext != infer.emptyContext; 851 if (inferDiag && (!diag.inferKey.equals(diag.basicKey))) { 852 Object[] args2 = new Object[args.length + 1]; 853 System.arraycopy(args, 0, args2, 1, args.length); 854 args2[0] = inferenceContext.inferenceVars(); 855 args = args2; 856 } 857 String key = inferDiag ? diag.inferKey : diag.basicKey; 858 throw inferDiag ? 859 infer.error(diags.create(DiagnosticType.FRAGMENT, log.currentSource(), pos, key, args)) : 860 methodCheckFailure.setMessage(diags.create(DiagnosticType.FRAGMENT, log.currentSource(), pos, key, args)); 861 } 862 863 /** 864 * To eliminate the overhead associated with allocating an exception object in such an 865 * hot execution path, we use flyweight pattern - and share the same exception instance 866 * across multiple method check failures. 867 */ 868 class SharedInapplicableMethodException extends InapplicableMethodException { 869 private static final long serialVersionUID = 0; 870 871 SharedInapplicableMethodException() { 872 super(null); 873 } 874 875 SharedInapplicableMethodException setMessage(JCDiagnostic details) { 876 this.diagnostic = details; 877 return this; 878 } 879 } 880 881 SharedInapplicableMethodException methodCheckFailure = new SharedInapplicableMethodException(); 882 883 public MethodCheck mostSpecificCheck(List<Type> actuals) { 884 return nilMethodCheck; 885 } 886 887 } 888 889 /** 890 * Arity-based method check. A method is applicable if the number of actuals 891 * supplied conforms to the method signature. 892 */ 893 MethodCheck arityMethodCheck = new AbstractMethodCheck() { 894 @Override 895 void checkArg(DiagnosticPosition pos, boolean varargs, Type actual, Type formal, DeferredAttrContext deferredAttrContext, Warner warn) { 896 //do nothing - actual always compatible to formals 897 } 898 899 @Override 900 public String toString() { 901 return "arityMethodCheck"; 902 } 903 }; 904 905 /** 906 * Main method applicability routine. Given a list of actual types A, 907 * a list of formal types F, determines whether the types in A are 908 * compatible (by method invocation conversion) with the types in F. 909 * 910 * Since this routine is shared between overload resolution and method 911 * type-inference, a (possibly empty) inference context is used to convert 912 * formal types to the corresponding 'undet' form ahead of a compatibility 913 * check so that constraints can be propagated and collected. 914 * 915 * Moreover, if one or more types in A is a deferred type, this routine uses 916 * DeferredAttr in order to perform deferred attribution. If one or more actual 917 * deferred types are stuck, they are placed in a queue and revisited later 918 * after the remainder of the arguments have been seen. If this is not sufficient 919 * to 'unstuck' the argument, a cyclic inference error is called out. 920 * 921 * A method check handler (see above) is used in order to report errors. 922 */ 923 MethodCheck resolveMethodCheck = new AbstractMethodCheck() { 924 925 @Override 926 void checkArg(DiagnosticPosition pos, boolean varargs, Type actual, Type formal, DeferredAttrContext deferredAttrContext, Warner warn) { 927 ResultInfo mresult = methodCheckResult(varargs, formal, deferredAttrContext, warn); 928 mresult.check(pos, actual); 929 } 930 931 @Override 932 public void argumentsAcceptable(final Env<AttrContext> env, 933 DeferredAttrContext deferredAttrContext, 934 List<Type> argtypes, 935 List<Type> formals, 936 Warner warn) { 937 super.argumentsAcceptable(env, deferredAttrContext, argtypes, formals, warn); 938 // should we check varargs element type accessibility? 939 if (deferredAttrContext.phase.isVarargsRequired()) { 940 if (deferredAttrContext.mode == AttrMode.CHECK) { 941 varargsAccessible(env, types.elemtype(formals.last()), deferredAttrContext.inferenceContext); 942 } 943 } 944 } 945 946 /** 947 * Test that the runtime array element type corresponding to 't' is accessible. 't' should be the 948 * varargs element type of either the method invocation type signature (after inference completes) 949 * or the method declaration signature (before inference completes). 950 */ 951 private void varargsAccessible(final Env<AttrContext> env, final Type t, final InferenceContext inferenceContext) { 952 if (inferenceContext.free(t)) { 953 inferenceContext.addFreeTypeListener(List.of(t), 954 solvedContext -> varargsAccessible(env, solvedContext.asInstType(t), solvedContext)); 955 } else { 956 if (!isAccessible(env, types.erasure(t))) { 957 Symbol location = env.enclClass.sym; 958 reportMC(env.tree, MethodCheckDiag.INACCESSIBLE_VARARGS, inferenceContext, t, Kinds.kindName(location), location); 959 } 960 } 961 } 962 963 private ResultInfo methodCheckResult(final boolean varargsCheck, Type to, 964 final DeferredAttr.DeferredAttrContext deferredAttrContext, Warner rsWarner) { 965 CheckContext checkContext = new MethodCheckContext(!deferredAttrContext.phase.isBoxingRequired(), deferredAttrContext, rsWarner) { 966 MethodCheckDiag methodDiag = varargsCheck ? 967 MethodCheckDiag.VARARG_MISMATCH : MethodCheckDiag.ARG_MISMATCH; 968 969 @Override 970 public void report(DiagnosticPosition pos, JCDiagnostic details) { 971 reportMC(pos, methodDiag, deferredAttrContext.inferenceContext, details); 972 } 973 }; 974 return new MethodResultInfo(to, checkContext); 975 } 976 977 @Override 978 public MethodCheck mostSpecificCheck(List<Type> actuals) { 979 return new MostSpecificCheck(actuals); 980 } 981 982 @Override 983 public String toString() { 984 return "resolveMethodCheck"; 985 } 986 }; 987 988 /** 989 * This class handles method reference applicability checks; since during 990 * these checks it's sometime possible to have inference variables on 991 * the actual argument types list, the method applicability check must be 992 * extended so that inference variables are 'opened' as needed. 993 */ 994 class MethodReferenceCheck extends AbstractMethodCheck { 995 996 InferenceContext pendingInferenceContext; 997 998 MethodReferenceCheck(InferenceContext pendingInferenceContext) { 999 this.pendingInferenceContext = pendingInferenceContext; 1000 } 1001 1002 @Override 1003 void checkArg(DiagnosticPosition pos, boolean varargs, Type actual, Type formal, DeferredAttrContext deferredAttrContext, Warner warn) { 1004 ResultInfo mresult = methodCheckResult(varargs, formal, deferredAttrContext, warn); 1005 mresult.check(pos, actual); 1006 } 1007 1008 private ResultInfo methodCheckResult(final boolean varargsCheck, Type to, 1009 final DeferredAttr.DeferredAttrContext deferredAttrContext, Warner rsWarner) { 1010 CheckContext checkContext = new MethodCheckContext(!deferredAttrContext.phase.isBoxingRequired(), deferredAttrContext, rsWarner) { 1011 MethodCheckDiag methodDiag = varargsCheck ? 1012 MethodCheckDiag.VARARG_MISMATCH : MethodCheckDiag.ARG_MISMATCH; 1013 1014 @Override 1015 public boolean compatible(Type found, Type req, Warner warn) { 1016 found = pendingInferenceContext.asUndetVar(found); 1017 if (found.hasTag(UNDETVAR) && req.isPrimitive()) { 1018 req = types.boxedClass(req).type; 1019 } 1020 return super.compatible(found, req, warn); 1021 } 1022 1023 @Override 1024 public void report(DiagnosticPosition pos, JCDiagnostic details) { 1025 reportMC(pos, methodDiag, deferredAttrContext.inferenceContext, details); 1026 } 1027 }; 1028 return new MethodResultInfo(to, checkContext); 1029 } 1030 1031 @Override 1032 public MethodCheck mostSpecificCheck(List<Type> actuals) { 1033 return new MostSpecificCheck(actuals); 1034 } 1035 1036 @Override 1037 public String toString() { 1038 return "MethodReferenceCheck"; 1039 } 1040 } 1041 1042 /** 1043 * Check context to be used during method applicability checks. A method check 1044 * context might contain inference variables. 1045 */ 1046 abstract class MethodCheckContext implements CheckContext { 1047 1048 boolean strict; 1049 DeferredAttrContext deferredAttrContext; 1050 Warner rsWarner; 1051 1052 public MethodCheckContext(boolean strict, DeferredAttrContext deferredAttrContext, Warner rsWarner) { 1053 this.strict = strict; 1054 this.deferredAttrContext = deferredAttrContext; 1055 this.rsWarner = rsWarner; 1056 } 1057 1058 public boolean compatible(Type found, Type req, Warner warn) { 1059 InferenceContext inferenceContext = deferredAttrContext.inferenceContext; 1060 return strict ? 1061 types.isSubtypeUnchecked(inferenceContext.asUndetVar(found), inferenceContext.asUndetVar(req), warn) : 1062 types.isConvertible(inferenceContext.asUndetVar(found), inferenceContext.asUndetVar(req), warn); 1063 } 1064 1065 public void report(DiagnosticPosition pos, JCDiagnostic details) { 1066 throw new InapplicableMethodException(details); 1067 } 1068 1069 public Warner checkWarner(DiagnosticPosition pos, Type found, Type req) { 1070 return rsWarner; 1071 } 1072 1073 public InferenceContext inferenceContext() { 1074 return deferredAttrContext.inferenceContext; 1075 } 1076 1077 public DeferredAttrContext deferredAttrContext() { 1078 return deferredAttrContext; 1079 } 1080 1081 @Override 1082 public String toString() { 1083 return "MethodCheckContext"; 1084 } 1085 } 1086 1087 /** 1088 * ResultInfo class to be used during method applicability checks. Check 1089 * for deferred types goes through special path. 1090 */ 1091 class MethodResultInfo extends ResultInfo { 1092 1093 public MethodResultInfo(Type pt, CheckContext checkContext) { 1094 attr.super(KindSelector.VAL, pt, checkContext); 1095 } 1096 1097 @Override 1098 protected Type check(DiagnosticPosition pos, Type found) { 1099 if (found.hasTag(DEFERRED)) { 1100 DeferredType dt = (DeferredType)found; 1101 return dt.check(this); 1102 } else { 1103 Type uResult = U(found); 1104 Type capturedType = pos == null || pos.getTree() == null ? 1105 types.capture(uResult) : 1106 checkContext.inferenceContext() 1107 .cachedCapture(pos.getTree(), uResult, true); 1108 return super.check(pos, chk.checkNonVoid(pos, capturedType)); 1109 } 1110 } 1111 1112 /** 1113 * javac has a long-standing 'simplification' (see 6391995): 1114 * given an actual argument type, the method check is performed 1115 * on its upper bound. This leads to inconsistencies when an 1116 * argument type is checked against itself. For example, given 1117 * a type-variable T, it is not true that {@code U(T) <: T}, 1118 * so we need to guard against that. 1119 */ 1120 private Type U(Type found) { 1121 return found == pt ? 1122 found : types.cvarUpperBound(found); 1123 } 1124 1125 @Override 1126 protected MethodResultInfo dup(Type newPt) { 1127 return new MethodResultInfo(newPt, checkContext); 1128 } 1129 1130 @Override 1131 protected ResultInfo dup(CheckContext newContext) { 1132 return new MethodResultInfo(pt, newContext); 1133 } 1134 1135 @Override 1136 protected ResultInfo dup(Type newPt, CheckContext newContext) { 1137 return new MethodResultInfo(newPt, newContext); 1138 } 1139 } 1140 1141 /** 1142 * Most specific method applicability routine. Given a list of actual types A, 1143 * a list of formal types F1, and a list of formal types F2, the routine determines 1144 * as to whether the types in F1 can be considered more specific than those in F2 w.r.t. 1145 * argument types A. 1146 */ 1147 class MostSpecificCheck implements MethodCheck { 1148 1149 List<Type> actuals; 1150 1151 MostSpecificCheck(List<Type> actuals) { 1152 this.actuals = actuals; 1153 } 1154 1155 @Override 1156 public void argumentsAcceptable(final Env<AttrContext> env, 1157 DeferredAttrContext deferredAttrContext, 1158 List<Type> formals1, 1159 List<Type> formals2, 1160 Warner warn) { 1161 formals2 = adjustArgs(formals2, deferredAttrContext.msym, formals1.length(), deferredAttrContext.phase.isVarargsRequired()); 1162 while (formals2.nonEmpty()) { 1163 ResultInfo mresult = methodCheckResult(formals2.head, deferredAttrContext, warn, actuals.head); 1164 mresult.check(null, formals1.head); 1165 formals1 = formals1.tail; 1166 formals2 = formals2.tail; 1167 actuals = actuals.isEmpty() ? actuals : actuals.tail; 1168 } 1169 } 1170 1171 /** 1172 * Create a method check context to be used during the most specific applicability check 1173 */ 1174 ResultInfo methodCheckResult(Type to, DeferredAttr.DeferredAttrContext deferredAttrContext, 1175 Warner rsWarner, Type actual) { 1176 return attr.new ResultInfo(KindSelector.VAL, to, 1177 new MostSpecificCheckContext(deferredAttrContext, rsWarner, actual)); 1178 } 1179 1180 /** 1181 * Subclass of method check context class that implements most specific 1182 * method conversion. If the actual type under analysis is a deferred type 1183 * a full blown structural analysis is carried out. 1184 */ 1185 class MostSpecificCheckContext extends MethodCheckContext { 1186 1187 Type actual; 1188 1189 public MostSpecificCheckContext(DeferredAttrContext deferredAttrContext, Warner rsWarner, Type actual) { 1190 super(true, deferredAttrContext, rsWarner); 1191 this.actual = actual; 1192 } 1193 1194 public boolean compatible(Type found, Type req, Warner warn) { 1195 if (unrelatedFunctionalInterfaces(found, req) && 1196 (actual != null && actual.getTag() == DEFERRED)) { 1197 DeferredType dt = (DeferredType) actual; 1198 JCTree speculativeTree = dt.speculativeTree(deferredAttrContext); 1199 if (speculativeTree != deferredAttr.stuckTree) { 1200 return functionalInterfaceMostSpecific(found, req, speculativeTree); 1201 } 1202 } 1203 return compatibleBySubtyping(found, req); 1204 } 1205 1206 private boolean compatibleBySubtyping(Type found, Type req) { 1207 if (!strict && found.isPrimitive() != req.isPrimitive()) { 1208 found = found.isPrimitive() ? types.boxedClass(found).type : types.unboxedType(found); 1209 } 1210 return types.isSubtypeNoCapture(found, deferredAttrContext.inferenceContext.asUndetVar(req)); 1211 } 1212 1213 /** Whether {@code t} and {@code s} are unrelated functional interface types. */ 1214 private boolean unrelatedFunctionalInterfaces(Type t, Type s) { 1215 return types.isFunctionalInterface(t.tsym) && 1216 types.isFunctionalInterface(s.tsym) && 1217 unrelatedInterfaces(t, s); 1218 } 1219 1220 /** Whether {@code t} and {@code s} are unrelated interface types; recurs on intersections. **/ 1221 private boolean unrelatedInterfaces(Type t, Type s) { 1222 if (t.isCompound()) { 1223 for (Type ti : types.interfaces(t)) { 1224 if (!unrelatedInterfaces(ti, s)) { 1225 return false; 1226 } 1227 } 1228 return true; 1229 } else if (s.isCompound()) { 1230 for (Type si : types.interfaces(s)) { 1231 if (!unrelatedInterfaces(t, si)) { 1232 return false; 1233 } 1234 } 1235 return true; 1236 } else { 1237 return types.asSuper(t, s.tsym) == null && types.asSuper(s, t.tsym) == null; 1238 } 1239 } 1240 1241 /** Parameters {@code t} and {@code s} are unrelated functional interface types. */ 1242 private boolean functionalInterfaceMostSpecific(Type t, Type s, JCTree tree) { 1243 Type tDesc = types.findDescriptorType(types.capture(t)); 1244 Type tDescNoCapture = types.findDescriptorType(t); 1245 Type sDesc = types.findDescriptorType(s); 1246 final List<Type> tTypeParams = tDesc.getTypeArguments(); 1247 final List<Type> tTypeParamsNoCapture = tDescNoCapture.getTypeArguments(); 1248 final List<Type> sTypeParams = sDesc.getTypeArguments(); 1249 1250 // compare type parameters 1251 if (tDesc.hasTag(FORALL) && !types.hasSameBounds((ForAll) tDesc, (ForAll) tDescNoCapture)) { 1252 return false; 1253 } 1254 // can't use Types.hasSameBounds on sDesc because bounds may have ivars 1255 List<Type> tIter = tTypeParams; 1256 List<Type> sIter = sTypeParams; 1257 while (tIter.nonEmpty() && sIter.nonEmpty()) { 1258 Type tBound = tIter.head.getUpperBound(); 1259 Type sBound = types.subst(sIter.head.getUpperBound(), sTypeParams, tTypeParams); 1260 if (tBound.containsAny(tTypeParams) && inferenceContext().free(sBound)) { 1261 return false; 1262 } 1263 if (!types.isSameType(tBound, inferenceContext().asUndetVar(sBound))) { 1264 return false; 1265 } 1266 tIter = tIter.tail; 1267 sIter = sIter.tail; 1268 } 1269 if (!tIter.isEmpty() || !sIter.isEmpty()) { 1270 return false; 1271 } 1272 1273 // compare parameters 1274 List<Type> tParams = tDesc.getParameterTypes(); 1275 List<Type> tParamsNoCapture = tDescNoCapture.getParameterTypes(); 1276 List<Type> sParams = sDesc.getParameterTypes(); 1277 while (tParams.nonEmpty() && tParamsNoCapture.nonEmpty() && sParams.nonEmpty()) { 1278 Type tParam = tParams.head; 1279 Type tParamNoCapture = types.subst(tParamsNoCapture.head, tTypeParamsNoCapture, tTypeParams); 1280 Type sParam = types.subst(sParams.head, sTypeParams, tTypeParams); 1281 if (tParam.containsAny(tTypeParams) && inferenceContext().free(sParam)) { 1282 return false; 1283 } 1284 if (!types.isSubtype(inferenceContext().asUndetVar(sParam), tParam)) { 1285 return false; 1286 } 1287 if (!types.isSameType(tParamNoCapture, inferenceContext().asUndetVar(sParam))) { 1288 return false; 1289 } 1290 tParams = tParams.tail; 1291 tParamsNoCapture = tParamsNoCapture.tail; 1292 sParams = sParams.tail; 1293 } 1294 if (!tParams.isEmpty() || !tParamsNoCapture.isEmpty() || !sParams.isEmpty()) { 1295 return false; 1296 } 1297 1298 // compare returns 1299 Type tRet = tDesc.getReturnType(); 1300 Type sRet = types.subst(sDesc.getReturnType(), sTypeParams, tTypeParams); 1301 if (tRet.containsAny(tTypeParams) && inferenceContext().free(sRet)) { 1302 return false; 1303 } 1304 MostSpecificFunctionReturnChecker msc = new MostSpecificFunctionReturnChecker(tRet, sRet); 1305 msc.scan(tree); 1306 return msc.result; 1307 } 1308 1309 /** 1310 * Tests whether one functional interface type can be considered more specific 1311 * than another unrelated functional interface type for the scanned expression. 1312 */ 1313 class MostSpecificFunctionReturnChecker extends DeferredAttr.PolyScanner { 1314 1315 final Type tRet; 1316 final Type sRet; 1317 boolean result; 1318 1319 /** Parameters {@code t} and {@code s} are unrelated functional interface types. */ 1320 MostSpecificFunctionReturnChecker(Type tRet, Type sRet) { 1321 this.tRet = tRet; 1322 this.sRet = sRet; 1323 result = true; 1324 } 1325 1326 @Override 1327 void skip(JCTree tree) { 1328 result = false; 1329 } 1330 1331 @Override 1332 public void visitConditional(JCConditional tree) { 1333 scan(asExpr(tree.truepart)); 1334 scan(asExpr(tree.falsepart)); 1335 } 1336 1337 @Override 1338 public void visitReference(JCMemberReference tree) { 1339 if (sRet.hasTag(VOID)) { 1340 // do nothing 1341 } else if (tRet.hasTag(VOID)) { 1342 result = false; 1343 } else if (tRet.isPrimitive() != sRet.isPrimitive()) { 1344 boolean retValIsPrimitive = 1345 tree.refPolyKind == PolyKind.STANDALONE && 1346 tree.sym.type.getReturnType().isPrimitive(); 1347 result &= (retValIsPrimitive == tRet.isPrimitive()) && 1348 (retValIsPrimitive != sRet.isPrimitive()); 1349 } else { 1350 result &= compatibleBySubtyping(tRet, sRet); 1351 } 1352 } 1353 1354 @Override 1355 public void visitParens(JCParens tree) { 1356 scan(asExpr(tree.expr)); 1357 } 1358 1359 @Override 1360 public void visitLambda(JCLambda tree) { 1361 if (sRet.hasTag(VOID)) { 1362 // do nothing 1363 } else if (tRet.hasTag(VOID)) { 1364 result = false; 1365 } else { 1366 List<JCExpression> lambdaResults = lambdaResults(tree); 1367 if (!lambdaResults.isEmpty() && unrelatedFunctionalInterfaces(tRet, sRet)) { 1368 for (JCExpression expr : lambdaResults) { 1369 result &= functionalInterfaceMostSpecific(tRet, sRet, expr); 1370 } 1371 } else if (!lambdaResults.isEmpty() && tRet.isPrimitive() != sRet.isPrimitive()) { 1372 for (JCExpression expr : lambdaResults) { 1373 boolean retValIsPrimitive = expr.isStandalone() && expr.type.isPrimitive(); 1374 result &= (retValIsPrimitive == tRet.isPrimitive()) && 1375 (retValIsPrimitive != sRet.isPrimitive()); 1376 } 1377 } else { 1378 result &= compatibleBySubtyping(tRet, sRet); 1379 } 1380 } 1381 } 1382 //where 1383 1384 private List<JCExpression> lambdaResults(JCLambda lambda) { 1385 if (lambda.getBodyKind() == JCTree.JCLambda.BodyKind.EXPRESSION) { 1386 return List.of(asExpr((JCExpression) lambda.body)); 1387 } else { 1388 final ListBuffer<JCExpression> buffer = new ListBuffer<>(); 1389 DeferredAttr.LambdaReturnScanner lambdaScanner = 1390 new DeferredAttr.LambdaReturnScanner() { 1391 @Override 1392 public void visitReturn(JCReturn tree) { 1393 if (tree.expr != null) { 1394 buffer.append(asExpr(tree.expr)); 1395 } 1396 } 1397 }; 1398 lambdaScanner.scan(lambda.body); 1399 return buffer.toList(); 1400 } 1401 } 1402 1403 private JCExpression asExpr(JCExpression expr) { 1404 if (expr.type.hasTag(DEFERRED)) { 1405 JCTree speculativeTree = ((DeferredType)expr.type).speculativeTree(deferredAttrContext); 1406 if (speculativeTree != deferredAttr.stuckTree) { 1407 expr = (JCExpression)speculativeTree; 1408 } 1409 } 1410 return expr; 1411 } 1412 } 1413 1414 } 1415 1416 public MethodCheck mostSpecificCheck(List<Type> actuals) { 1417 Assert.error("Cannot get here!"); 1418 return null; 1419 } 1420 } 1421 1422 public static class InapplicableMethodException extends RuntimeException { 1423 private static final long serialVersionUID = 0; 1424 1425 transient JCDiagnostic diagnostic; 1426 1427 InapplicableMethodException(JCDiagnostic diag) { 1428 this.diagnostic = diag; 1429 } 1430 1431 public JCDiagnostic getDiagnostic() { 1432 return diagnostic; 1433 } 1434 1435 @Override 1436 public Throwable fillInStackTrace() { 1437 // This is an internal exception; the stack trace is irrelevant. 1438 return this; 1439 } 1440 } 1441 1442 /* *************************************************************************** 1443 * Symbol lookup 1444 * the following naming conventions for arguments are used 1445 * 1446 * env is the environment where the symbol was mentioned 1447 * site is the type of which the symbol is a member 1448 * name is the symbol's name 1449 * if no arguments are given 1450 * argtypes are the value arguments, if we search for a method 1451 * 1452 * If no symbol was found, a ResolveError detailing the problem is returned. 1453 ****************************************************************************/ 1454 1455 /** Find field. Synthetic fields are always skipped. 1456 * @param env The current environment. 1457 * @param site The original type from where the selection takes place. 1458 * @param name The name of the field. 1459 * @param c The class to search for the field. This is always 1460 * a superclass or implemented interface of site's class. 1461 */ 1462 Symbol findField(Env<AttrContext> env, 1463 Type site, 1464 Name name, 1465 TypeSymbol c) { 1466 while (c.type.hasTag(TYPEVAR)) 1467 c = c.type.getUpperBound().tsym; 1468 Symbol bestSoFar = varNotFound; 1469 Symbol sym; 1470 for (Symbol s : c.members().getSymbolsByName(name)) { 1471 if (s.kind == VAR && (s.flags_field & SYNTHETIC) == 0) { 1472 return isAccessible(env, site, s) 1473 ? s : new AccessError(env, site, s); 1474 } 1475 } 1476 Type st = types.supertype(c.type); 1477 if (st != null && (st.hasTag(CLASS) || st.hasTag(TYPEVAR))) { 1478 sym = findField(env, site, name, st.tsym); 1479 bestSoFar = bestOf(bestSoFar, sym); 1480 } 1481 for (List<Type> l = types.interfaces(c.type); 1482 bestSoFar.kind != AMBIGUOUS && l.nonEmpty(); 1483 l = l.tail) { 1484 sym = findField(env, site, name, l.head.tsym); 1485 if (bestSoFar.exists() && sym.exists() && 1486 sym.owner != bestSoFar.owner) 1487 bestSoFar = new AmbiguityError(bestSoFar, sym); 1488 else 1489 bestSoFar = bestOf(bestSoFar, sym); 1490 } 1491 return bestSoFar; 1492 } 1493 1494 /** Resolve a field identifier, throw a fatal error if not found. 1495 * @param pos The position to use for error reporting. 1496 * @param env The environment current at the method invocation. 1497 * @param site The type of the qualifying expression, in which 1498 * identifier is searched. 1499 * @param name The identifier's name. 1500 */ 1501 public VarSymbol resolveInternalField(DiagnosticPosition pos, Env<AttrContext> env, 1502 Type site, Name name) { 1503 Symbol sym = findField(env, site, name, site.tsym); 1504 if (sym.kind == VAR) return (VarSymbol)sym; 1505 else throw new FatalError( 1506 diags.fragment(Fragments.FatalErrCantLocateField(name))); 1507 } 1508 1509 /** Find unqualified variable or field with given name. 1510 * Synthetic fields always skipped. 1511 * @param env The current environment. 1512 * @param name The name of the variable or field. 1513 */ 1514 Symbol findVar(Env<AttrContext> env, Name name) { 1515 Symbol bestSoFar = varNotFound; 1516 Env<AttrContext> env1 = env; 1517 boolean staticOnly = false; 1518 while (env1.outer != null) { 1519 Symbol sym = null; 1520 for (Symbol s : env1.info.scope.getSymbolsByName(name)) { 1521 if (s.kind == VAR && (s.flags_field & SYNTHETIC) == 0) { 1522 sym = s; 1523 if (staticOnly) { 1524 return new StaticError(sym); 1525 } 1526 break; 1527 } 1528 } 1529 if (isStatic(env1)) staticOnly = true; 1530 if (sym == null) { 1531 sym = findField(env1, env1.enclClass.sym.type, name, env1.enclClass.sym); 1532 } 1533 if (sym.exists()) { 1534 if (staticOnly && 1535 sym.kind == VAR && 1536 sym.owner.kind == TYP && 1537 (sym.flags() & STATIC) == 0) 1538 return new StaticError(sym); 1539 else 1540 return sym; 1541 } else { 1542 bestSoFar = bestOf(bestSoFar, sym); 1543 } 1544 1545 if ((env1.enclClass.sym.flags() & STATIC) != 0) staticOnly = true; 1546 env1 = env1.outer; 1547 } 1548 1549 Symbol sym = findField(env, syms.predefClass.type, name, syms.predefClass); 1550 if (sym.exists()) 1551 return sym; 1552 if (bestSoFar.exists()) 1553 return bestSoFar; 1554 1555 Symbol origin = null; 1556 for (Scope sc : new Scope[] { env.toplevel.namedImportScope, env.toplevel.starImportScope }) { 1557 for (Symbol currentSymbol : sc.getSymbolsByName(name)) { 1558 if (currentSymbol.kind != VAR) 1559 continue; 1560 // invariant: sym.kind == Symbol.Kind.VAR 1561 if (!bestSoFar.kind.isResolutionError() && 1562 currentSymbol.owner != bestSoFar.owner) 1563 return new AmbiguityError(bestSoFar, currentSymbol); 1564 else if (!bestSoFar.kind.betterThan(VAR)) { 1565 origin = sc.getOrigin(currentSymbol).owner; 1566 bestSoFar = isAccessible(env, origin.type, currentSymbol) 1567 ? currentSymbol : new AccessError(env, origin.type, currentSymbol); 1568 } 1569 } 1570 if (bestSoFar.exists()) break; 1571 } 1572 if (bestSoFar.kind == VAR && bestSoFar.owner.type != origin.type) 1573 return bestSoFar.clone(origin); 1574 else 1575 return bestSoFar; 1576 } 1577 1578 Warner noteWarner = new Warner(); 1579 1580 /** Select the best method for a call site among two choices. 1581 * @param env The current environment. 1582 * @param site The original type from where the 1583 * selection takes place. 1584 * @param argtypes The invocation's value arguments, 1585 * @param typeargtypes The invocation's type arguments, 1586 * @param sym Proposed new best match. 1587 * @param bestSoFar Previously found best match. 1588 * @param allowBoxing Allow boxing conversions of arguments. 1589 * @param useVarargs Box trailing arguments into an array for varargs. 1590 */ 1591 @SuppressWarnings("fallthrough") 1592 Symbol selectBest(Env<AttrContext> env, 1593 Type site, 1594 List<Type> argtypes, 1595 List<Type> typeargtypes, 1596 Symbol sym, 1597 Symbol bestSoFar, 1598 boolean allowBoxing, 1599 boolean useVarargs) { 1600 if (sym.kind == ERR || 1601 (site.tsym != sym.owner && !sym.isInheritedIn(site.tsym, types)) || 1602 !notOverriddenIn(site, sym)) { 1603 return bestSoFar; 1604 } else if (useVarargs && (sym.flags() & VARARGS) == 0) { 1605 return bestSoFar.kind.isResolutionError() ? 1606 new BadVarargsMethod((ResolveError)bestSoFar.baseSymbol()) : 1607 bestSoFar; 1608 } 1609 Assert.check(!sym.kind.isResolutionError()); 1610 try { 1611 types.noWarnings.clear(); 1612 Type mt = rawInstantiate(env, site, sym, null, argtypes, typeargtypes, 1613 allowBoxing, useVarargs, types.noWarnings); 1614 currentResolutionContext.addApplicableCandidate(sym, mt); 1615 } catch (InapplicableMethodException ex) { 1616 currentResolutionContext.addInapplicableCandidate(sym, ex.getDiagnostic()); 1617 // Currently, an InapplicableMethodException occurs. 1618 // If bestSoFar.kind was ABSENT_MTH, return an InapplicableSymbolError(kind is WRONG_MTH). 1619 // If bestSoFar.kind was HIDDEN(AccessError)/WRONG_MTH/WRONG_MTHS, return an InapplicableSymbolsError(kind is WRONG_MTHS). 1620 // See JDK-8255968 for more information. 1621 switch (bestSoFar.kind) { 1622 case ABSENT_MTH: 1623 return new InapplicableSymbolError(currentResolutionContext); 1624 case HIDDEN: 1625 if (bestSoFar instanceof AccessError accessError) { 1626 // Add the JCDiagnostic of previous AccessError to the currentResolutionContext 1627 // and construct InapplicableSymbolsError. 1628 // Intentionally fallthrough. 1629 currentResolutionContext.addInapplicableCandidate(accessError.sym, 1630 accessError.getDiagnostic(JCDiagnostic.DiagnosticType.FRAGMENT, null, null, site, null, argtypes, typeargtypes)); 1631 } else { 1632 return bestSoFar; 1633 } 1634 case WRONG_MTH: 1635 bestSoFar = new InapplicableSymbolsError(currentResolutionContext); 1636 default: 1637 return bestSoFar; 1638 } 1639 } 1640 if (!isAccessible(env, site, sym)) { 1641 AccessError curAccessError = new AccessError(env, site, sym); 1642 JCDiagnostic curDiagnostic = curAccessError.getDiagnostic(JCDiagnostic.DiagnosticType.FRAGMENT, null, null, site, null, argtypes, typeargtypes); 1643 // Currently, an AccessError occurs. 1644 // If bestSoFar.kind was ABSENT_MTH, return an AccessError(kind is HIDDEN). 1645 // If bestSoFar.kind was HIDDEN(AccessError), WRONG_MTH, WRONG_MTHS, return an InapplicableSymbolsError(kind is WRONG_MTHS). 1646 // See JDK-8255968 for more information. 1647 if (bestSoFar.kind == ABSENT_MTH) { 1648 bestSoFar = curAccessError; 1649 } else if (bestSoFar.kind == WRONG_MTH) { 1650 // Add the JCDiagnostic of current AccessError to the currentResolutionContext 1651 // and construct InapplicableSymbolsError. 1652 currentResolutionContext.addInapplicableCandidate(sym, curDiagnostic); 1653 bestSoFar = new InapplicableSymbolsError(currentResolutionContext); 1654 } else if (bestSoFar.kind == WRONG_MTHS) { 1655 // Add the JCDiagnostic of current AccessError to the currentResolutionContext 1656 currentResolutionContext.addInapplicableCandidate(sym, curDiagnostic); 1657 } else if (bestSoFar.kind == HIDDEN && bestSoFar instanceof AccessError accessError) { 1658 // Add the JCDiagnostics of previous and current AccessError to the currentResolutionContext 1659 // and construct InapplicableSymbolsError. 1660 currentResolutionContext.addInapplicableCandidate(accessError.sym, 1661 accessError.getDiagnostic(JCDiagnostic.DiagnosticType.FRAGMENT, null, null, site, null, argtypes, typeargtypes)); 1662 currentResolutionContext.addInapplicableCandidate(sym, curDiagnostic); 1663 bestSoFar = new InapplicableSymbolsError(currentResolutionContext); 1664 } 1665 return bestSoFar; 1666 } 1667 return (bestSoFar.kind.isResolutionError() && bestSoFar.kind != AMBIGUOUS) 1668 ? sym 1669 : mostSpecific(argtypes, sym, bestSoFar, env, site, useVarargs); 1670 } 1671 1672 /* Return the most specific of the two methods for a call, 1673 * given that both are accessible and applicable. 1674 * @param m1 A new candidate for most specific. 1675 * @param m2 The previous most specific candidate. 1676 * @param env The current environment. 1677 * @param site The original type from where the selection 1678 * takes place. 1679 * @param allowBoxing Allow boxing conversions of arguments. 1680 * @param useVarargs Box trailing arguments into an array for varargs. 1681 */ 1682 Symbol mostSpecific(List<Type> argtypes, Symbol m1, 1683 Symbol m2, 1684 Env<AttrContext> env, 1685 final Type site, 1686 boolean useVarargs) { 1687 switch (m2.kind) { 1688 case MTH: 1689 if (m1 == m2) return m1; 1690 boolean m1SignatureMoreSpecific = 1691 signatureMoreSpecific(argtypes, env, site, m1, m2, useVarargs); 1692 boolean m2SignatureMoreSpecific = 1693 signatureMoreSpecific(argtypes, env, site, m2, m1, useVarargs); 1694 if (m1SignatureMoreSpecific && m2SignatureMoreSpecific) { 1695 Type mt1 = types.memberType(site, m1); 1696 Type mt2 = types.memberType(site, m2); 1697 if (!types.overrideEquivalent(mt1, mt2)) 1698 return ambiguityError(m1, m2); 1699 1700 // same signature; select (a) the non-bridge method, or 1701 // (b) the one that overrides the other, or (c) the concrete 1702 // one, or (d) merge both abstract signatures 1703 if ((m1.flags() & BRIDGE) != (m2.flags() & BRIDGE)) 1704 return ((m1.flags() & BRIDGE) != 0) ? m2 : m1; 1705 1706 if (m1.baseSymbol() == m2.baseSymbol()) { 1707 // this is the same imported symbol which has been cloned twice. 1708 // Return the first one (either will do). 1709 return m1; 1710 } 1711 1712 // if one overrides or hides the other, use it 1713 TypeSymbol m1Owner = (TypeSymbol)m1.owner; 1714 TypeSymbol m2Owner = (TypeSymbol)m2.owner; 1715 // the two owners can never be the same if the target methods are compiled from source, 1716 // but we need to protect against cases where the methods are defined in some classfile 1717 // and make sure we issue an ambiguity error accordingly (by skipping the logic below). 1718 if (m1Owner != m2Owner) { 1719 if (types.asSuper(m1Owner.type.referenceProjectionOrSelf(), m2Owner) != null && 1720 ((m1.owner.flags_field & INTERFACE) == 0 || 1721 (m2.owner.flags_field & INTERFACE) != 0) && 1722 m1.overrides(m2, m1Owner, types, false)) 1723 return m1; 1724 if (types.asSuper(m2Owner.type.referenceProjectionOrSelf(), m1Owner) != null && 1725 ((m2.owner.flags_field & INTERFACE) == 0 || 1726 (m1.owner.flags_field & INTERFACE) != 0) && 1727 m2.overrides(m1, m2Owner, types, false)) 1728 return m2; 1729 } 1730 boolean m1Abstract = (m1.flags() & ABSTRACT) != 0; 1731 boolean m2Abstract = (m2.flags() & ABSTRACT) != 0; 1732 if (m1Abstract && !m2Abstract) return m2; 1733 if (m2Abstract && !m1Abstract) return m1; 1734 // both abstract or both concrete 1735 return ambiguityError(m1, m2); 1736 } 1737 if (m1SignatureMoreSpecific) return m1; 1738 if (m2SignatureMoreSpecific) return m2; 1739 return ambiguityError(m1, m2); 1740 case AMBIGUOUS: 1741 //compare m1 to ambiguous methods in m2 1742 AmbiguityError e = (AmbiguityError)m2.baseSymbol(); 1743 boolean m1MoreSpecificThanAnyAmbiguous = true; 1744 boolean allAmbiguousMoreSpecificThanM1 = true; 1745 for (Symbol s : e.ambiguousSyms) { 1746 Symbol moreSpecific = mostSpecific(argtypes, m1, s, env, site, useVarargs); 1747 m1MoreSpecificThanAnyAmbiguous &= moreSpecific == m1; 1748 allAmbiguousMoreSpecificThanM1 &= moreSpecific == s; 1749 } 1750 if (m1MoreSpecificThanAnyAmbiguous) 1751 return m1; 1752 //if m1 is more specific than some ambiguous methods, but other ambiguous methods are 1753 //more specific than m1, add it as a new ambiguous method: 1754 if (!allAmbiguousMoreSpecificThanM1) 1755 e.addAmbiguousSymbol(m1); 1756 return e; 1757 default: 1758 throw new AssertionError(); 1759 } 1760 } 1761 //where 1762 private boolean signatureMoreSpecific(List<Type> actuals, Env<AttrContext> env, Type site, Symbol m1, Symbol m2, boolean useVarargs) { 1763 noteWarner.clear(); 1764 int maxLength = Math.max( 1765 Math.max(m1.type.getParameterTypes().length(), actuals.length()), 1766 m2.type.getParameterTypes().length()); 1767 MethodResolutionContext prevResolutionContext = currentResolutionContext; 1768 try { 1769 currentResolutionContext = new MethodResolutionContext(); 1770 currentResolutionContext.step = prevResolutionContext.step; 1771 currentResolutionContext.methodCheck = 1772 prevResolutionContext.methodCheck.mostSpecificCheck(actuals); 1773 Type mst = instantiate(env, site, m2, null, 1774 adjustArgs(types.cvarLowerBounds(types.memberType(site, m1).getParameterTypes()), m1, maxLength, useVarargs), null, 1775 false, useVarargs, noteWarner); 1776 return mst != null && 1777 !noteWarner.hasLint(Lint.LintCategory.UNCHECKED); 1778 } finally { 1779 currentResolutionContext = prevResolutionContext; 1780 } 1781 } 1782 1783 List<Type> adjustArgs(List<Type> args, Symbol msym, int length, boolean allowVarargs) { 1784 if ((msym.flags() & VARARGS) != 0 && allowVarargs) { 1785 Type varargsElem = types.elemtype(args.last()); 1786 if (varargsElem == null) { 1787 Assert.error("Bad varargs = " + args.last() + " " + msym); 1788 } 1789 List<Type> newArgs = args.reverse().tail.prepend(varargsElem).reverse(); 1790 while (newArgs.length() < length) { 1791 newArgs = newArgs.append(newArgs.last()); 1792 } 1793 return newArgs; 1794 } else { 1795 return args; 1796 } 1797 } 1798 //where 1799 Symbol ambiguityError(Symbol m1, Symbol m2) { 1800 if (((m1.flags() | m2.flags()) & CLASH) != 0) { 1801 return (m1.flags() & CLASH) == 0 ? m1 : m2; 1802 } else { 1803 return new AmbiguityError(m1, m2); 1804 } 1805 } 1806 1807 Symbol findMethodInScope(Env<AttrContext> env, 1808 Type site, 1809 Name name, 1810 List<Type> argtypes, 1811 List<Type> typeargtypes, 1812 Scope sc, 1813 Symbol bestSoFar, 1814 boolean allowBoxing, 1815 boolean useVarargs, 1816 boolean abstractok) { 1817 for (Symbol s : sc.getSymbolsByName(name, new LookupFilter(abstractok))) { 1818 bestSoFar = selectBest(env, site, argtypes, typeargtypes, s, 1819 bestSoFar, allowBoxing, useVarargs); 1820 } 1821 return bestSoFar; 1822 } 1823 //where 1824 class LookupFilter implements Predicate<Symbol> { 1825 1826 boolean abstractOk; 1827 1828 LookupFilter(boolean abstractOk) { 1829 this.abstractOk = abstractOk; 1830 } 1831 1832 @Override 1833 public boolean test(Symbol s) { 1834 long flags = s.flags(); 1835 return s.kind == MTH && 1836 (flags & SYNTHETIC) == 0 && 1837 (abstractOk || 1838 (flags & DEFAULT) != 0 || 1839 (flags & ABSTRACT) == 0); 1840 } 1841 } 1842 1843 /** Find best qualified method matching given name, type and value 1844 * arguments. 1845 * @param env The current environment. 1846 * @param site The original type from where the selection 1847 * takes place. 1848 * @param name The method's name. 1849 * @param argtypes The method's value arguments. 1850 * @param typeargtypes The method's type arguments 1851 * @param allowBoxing Allow boxing conversions of arguments. 1852 * @param useVarargs Box trailing arguments into an array for varargs. 1853 */ 1854 Symbol findMethod(Env<AttrContext> env, 1855 Type site, 1856 Name name, 1857 List<Type> argtypes, 1858 List<Type> typeargtypes, 1859 boolean allowBoxing, 1860 boolean useVarargs) { 1861 Symbol bestSoFar = methodNotFound; 1862 bestSoFar = findMethod(env, 1863 site, 1864 name, 1865 argtypes, 1866 typeargtypes, 1867 site.tsym.type, 1868 bestSoFar, 1869 allowBoxing, 1870 useVarargs); 1871 return bestSoFar; 1872 } 1873 // where 1874 private Symbol findMethod(Env<AttrContext> env, 1875 Type site, 1876 Name name, 1877 List<Type> argtypes, 1878 List<Type> typeargtypes, 1879 Type intype, 1880 Symbol bestSoFar, 1881 boolean allowBoxing, 1882 boolean useVarargs) { 1883 @SuppressWarnings({"unchecked","rawtypes"}) 1884 List<Type>[] itypes = (List<Type>[])new List[] { List.<Type>nil(), List.<Type>nil() }; 1885 1886 InterfaceLookupPhase iphase = InterfaceLookupPhase.ABSTRACT_OK; 1887 boolean isInterface = site.tsym.isInterface(); 1888 for (TypeSymbol s : isInterface ? List.of(intype.tsym) : superclasses(intype)) { 1889 bestSoFar = findMethodInScope(env, site, name, argtypes, typeargtypes, 1890 s.members(), bestSoFar, allowBoxing, useVarargs, true); 1891 if (names.isInitOrVNew(name)) return bestSoFar; 1892 iphase = (iphase == null) ? null : iphase.update(s, this); 1893 if (iphase != null) { 1894 for (Type itype : types.interfaces(s.type)) { 1895 itypes[iphase.ordinal()] = types.union(types.closure(itype), itypes[iphase.ordinal()]); 1896 } 1897 } 1898 } 1899 1900 Symbol concrete = bestSoFar.kind.isValid() && 1901 (bestSoFar.flags() & ABSTRACT) == 0 ? 1902 bestSoFar : methodNotFound; 1903 1904 for (InterfaceLookupPhase iphase2 : InterfaceLookupPhase.values()) { 1905 //keep searching for abstract methods 1906 for (Type itype : itypes[iphase2.ordinal()]) { 1907 if (!itype.isInterface()) continue; //skip j.l.Object (included by Types.closure()) 1908 if (iphase2 == InterfaceLookupPhase.DEFAULT_OK && 1909 (itype.tsym.flags() & DEFAULT) == 0) continue; 1910 bestSoFar = findMethodInScope(env, site, name, argtypes, typeargtypes, 1911 itype.tsym.members(), bestSoFar, allowBoxing, useVarargs, true); 1912 if (concrete != bestSoFar && 1913 concrete.kind.isValid() && 1914 bestSoFar.kind.isValid() && 1915 types.isSubSignature(concrete.type, bestSoFar.type)) { 1916 //this is an hack - as javac does not do full membership checks 1917 //most specific ends up comparing abstract methods that might have 1918 //been implemented by some concrete method in a subclass and, 1919 //because of raw override, it is possible for an abstract method 1920 //to be more specific than the concrete method - so we need 1921 //to explicitly call that out (see CR 6178365) 1922 bestSoFar = concrete; 1923 } 1924 } 1925 } 1926 if (isInterface && bestSoFar.kind.isResolutionError()) { 1927 bestSoFar = findMethodInScope(env, site, name, argtypes, typeargtypes, 1928 syms.objectType.tsym.members(), bestSoFar, allowBoxing, useVarargs, true); 1929 if (bestSoFar.kind.isValid()) { 1930 Symbol baseSymbol = bestSoFar; 1931 bestSoFar = new MethodSymbol(bestSoFar.flags_field, bestSoFar.name, bestSoFar.type, intype.tsym) { 1932 @Override 1933 public Symbol baseSymbol() { 1934 return baseSymbol; 1935 } 1936 }; 1937 } 1938 } 1939 return bestSoFar; 1940 } 1941 1942 enum InterfaceLookupPhase { 1943 ABSTRACT_OK() { 1944 @Override 1945 InterfaceLookupPhase update(Symbol s, Resolve rs) { 1946 //We should not look for abstract methods if receiver is a concrete class 1947 //(as concrete classes are expected to implement all abstracts coming 1948 //from superinterfaces) 1949 if ((s.flags() & (ABSTRACT | INTERFACE | ENUM)) != 0) { 1950 return this; 1951 } else { 1952 return DEFAULT_OK; 1953 } 1954 } 1955 }, 1956 DEFAULT_OK() { 1957 @Override 1958 InterfaceLookupPhase update(Symbol s, Resolve rs) { 1959 return this; 1960 } 1961 }; 1962 1963 abstract InterfaceLookupPhase update(Symbol s, Resolve rs); 1964 } 1965 1966 /** 1967 * Return an Iterable object to scan the superclasses of a given type. 1968 * It's crucial that the scan is done lazily, as we don't want to accidentally 1969 * access more supertypes than strictly needed (as this could trigger completion 1970 * errors if some of the not-needed supertypes are missing/ill-formed). 1971 */ 1972 Iterable<TypeSymbol> superclasses(final Type intype) { 1973 return () -> new Iterator<TypeSymbol>() { 1974 1975 List<TypeSymbol> seen = List.nil(); 1976 TypeSymbol currentSym = symbolFor(intype); 1977 TypeSymbol prevSym = null; 1978 1979 public boolean hasNext() { 1980 if (currentSym == syms.noSymbol) { 1981 currentSym = symbolFor(types.supertype(prevSym.type)); 1982 } 1983 return currentSym != null; 1984 } 1985 1986 public TypeSymbol next() { 1987 prevSym = currentSym; 1988 currentSym = syms.noSymbol; 1989 Assert.check(prevSym != null || prevSym != syms.noSymbol); 1990 return prevSym; 1991 } 1992 1993 public void remove() { 1994 throw new UnsupportedOperationException(); 1995 } 1996 1997 TypeSymbol symbolFor(Type t) { 1998 if (!t.hasTag(CLASS) && 1999 !t.hasTag(TYPEVAR)) { 2000 return null; 2001 } 2002 t = types.skipTypeVars(t, false); 2003 if (seen.contains(t.tsym)) { 2004 //degenerate case in which we have a circular 2005 //class hierarchy - because of ill-formed classfiles 2006 return null; 2007 } 2008 seen = seen.prepend(t.tsym); 2009 return t.tsym; 2010 } 2011 }; 2012 } 2013 2014 /** Find unqualified method matching given name, type and value arguments. 2015 * @param env The current environment. 2016 * @param name The method's name. 2017 * @param argtypes The method's value arguments. 2018 * @param typeargtypes The method's type arguments. 2019 * @param allowBoxing Allow boxing conversions of arguments. 2020 * @param useVarargs Box trailing arguments into an array for varargs. 2021 */ 2022 Symbol findFun(Env<AttrContext> env, Name name, 2023 List<Type> argtypes, List<Type> typeargtypes, 2024 boolean allowBoxing, boolean useVarargs) { 2025 Symbol bestSoFar = methodNotFound; 2026 Env<AttrContext> env1 = env; 2027 boolean staticOnly = false; 2028 while (env1.outer != null) { 2029 if (isStatic(env1)) staticOnly = true; 2030 Assert.check(env1.info.preferredTreeForDiagnostics == null); 2031 env1.info.preferredTreeForDiagnostics = env.tree; 2032 try { 2033 Symbol sym = findMethod( 2034 env1, env1.enclClass.sym.type, name, argtypes, typeargtypes, 2035 allowBoxing, useVarargs); 2036 if (sym.exists()) { 2037 if (staticOnly && 2038 sym.kind == MTH && 2039 sym.owner.kind == TYP && 2040 (sym.flags() & STATIC) == 0) return new StaticError(sym); 2041 else return sym; 2042 } else { 2043 bestSoFar = bestOf(bestSoFar, sym); 2044 } 2045 } finally { 2046 env1.info.preferredTreeForDiagnostics = null; 2047 } 2048 if ((env1.enclClass.sym.flags() & STATIC) != 0) staticOnly = true; 2049 env1 = env1.outer; 2050 } 2051 2052 Symbol sym = findMethod(env, syms.predefClass.type, name, argtypes, 2053 typeargtypes, allowBoxing, useVarargs); 2054 if (sym.exists()) 2055 return sym; 2056 2057 for (Symbol currentSym : env.toplevel.namedImportScope.getSymbolsByName(name)) { 2058 Symbol origin = env.toplevel.namedImportScope.getOrigin(currentSym).owner; 2059 if (currentSym.kind == MTH) { 2060 if (currentSym.owner.type != origin.type) 2061 currentSym = currentSym.clone(origin); 2062 if (!isAccessible(env, origin.type, currentSym)) 2063 currentSym = new AccessError(env, origin.type, currentSym); 2064 bestSoFar = selectBest(env, origin.type, 2065 argtypes, typeargtypes, 2066 currentSym, bestSoFar, 2067 allowBoxing, useVarargs); 2068 } 2069 } 2070 if (bestSoFar.exists()) 2071 return bestSoFar; 2072 2073 for (Symbol currentSym : env.toplevel.starImportScope.getSymbolsByName(name)) { 2074 Symbol origin = env.toplevel.starImportScope.getOrigin(currentSym).owner; 2075 if (currentSym.kind == MTH) { 2076 if (currentSym.owner.type != origin.type) 2077 currentSym = currentSym.clone(origin); 2078 if (!isAccessible(env, origin.type, currentSym)) 2079 currentSym = new AccessError(env, origin.type, currentSym); 2080 bestSoFar = selectBest(env, origin.type, 2081 argtypes, typeargtypes, 2082 currentSym, bestSoFar, 2083 allowBoxing, useVarargs); 2084 } 2085 } 2086 return bestSoFar; 2087 } 2088 2089 /** Load toplevel or member class with given fully qualified name and 2090 * verify that it is accessible. 2091 * @param env The current environment. 2092 * @param name The fully qualified name of the class to be loaded. 2093 */ 2094 Symbol loadClass(Env<AttrContext> env, Name name, RecoveryLoadClass recoveryLoadClass) { 2095 try { 2096 ClassSymbol c = finder.loadClass(env.toplevel.modle, name); 2097 return isAccessible(env, c) ? c : new AccessError(env, null, c); 2098 } catch (ClassFinder.BadClassFile err) { 2099 return new BadClassFileError(err); 2100 } catch (CompletionFailure ex) { 2101 Symbol candidate = recoveryLoadClass.loadClass(env, name); 2102 2103 if (candidate != null) { 2104 return candidate; 2105 } 2106 2107 return typeNotFound; 2108 } 2109 } 2110 2111 public interface RecoveryLoadClass { 2112 Symbol loadClass(Env<AttrContext> env, Name name); 2113 } 2114 2115 private final RecoveryLoadClass noRecovery = (env, name) -> null; 2116 2117 private final RecoveryLoadClass doRecoveryLoadClass = new RecoveryLoadClass() { 2118 @Override public Symbol loadClass(Env<AttrContext> env, Name name) { 2119 List<Name> candidates = Convert.classCandidates(name); 2120 return lookupInvisibleSymbol(env, name, 2121 n -> () -> createCompoundIterator(candidates, 2122 c -> syms.getClassesForName(c) 2123 .iterator()), 2124 (ms, n) -> { 2125 for (Name candidate : candidates) { 2126 try { 2127 return finder.loadClass(ms, candidate); 2128 } catch (CompletionFailure cf) { 2129 //ignore 2130 } 2131 } 2132 return null; 2133 }, sym -> sym.kind == Kind.TYP, typeNotFound); 2134 } 2135 }; 2136 2137 private final RecoveryLoadClass namedImportScopeRecovery = (env, name) -> { 2138 Scope importScope = env.toplevel.namedImportScope; 2139 Symbol existing = importScope.findFirst(Convert.shortName(name), 2140 sym -> sym.kind == TYP && sym.flatName() == name); 2141 2142 if (existing != null) { 2143 return new InvisibleSymbolError(env, true, existing); 2144 } 2145 return null; 2146 }; 2147 2148 private final RecoveryLoadClass starImportScopeRecovery = (env, name) -> { 2149 Scope importScope = env.toplevel.starImportScope; 2150 Symbol existing = importScope.findFirst(Convert.shortName(name), 2151 sym -> sym.kind == TYP && sym.flatName() == name); 2152 2153 if (existing != null) { 2154 try { 2155 existing = finder.loadClass(existing.packge().modle, name); 2156 2157 return new InvisibleSymbolError(env, true, existing); 2158 } catch (CompletionFailure cf) { 2159 //ignore 2160 } 2161 } 2162 2163 return null; 2164 }; 2165 2166 Symbol lookupPackage(Env<AttrContext> env, Name name) { 2167 PackageSymbol pack = syms.lookupPackage(env.toplevel.modle, name); 2168 2169 if (allowModules && isImportOnDemand(env, name)) { 2170 if (pack.members().isEmpty()) { 2171 return lookupInvisibleSymbol(env, name, syms::getPackagesForName, syms::enterPackage, sym -> { 2172 sym.complete(); 2173 return !sym.members().isEmpty(); 2174 }, pack); 2175 } 2176 } 2177 2178 return pack; 2179 } 2180 2181 private boolean isImportOnDemand(Env<AttrContext> env, Name name) { 2182 if (!env.tree.hasTag(IMPORT)) 2183 return false; 2184 2185 JCTree qualid = ((JCImport) env.tree).qualid; 2186 2187 if (!qualid.hasTag(SELECT)) 2188 return false; 2189 2190 if (TreeInfo.name(qualid) != names.asterisk) 2191 return false; 2192 2193 return TreeInfo.fullName(((JCFieldAccess) qualid).selected) == name; 2194 } 2195 2196 private <S extends Symbol> Symbol lookupInvisibleSymbol(Env<AttrContext> env, 2197 Name name, 2198 Function<Name, Iterable<S>> get, 2199 BiFunction<ModuleSymbol, Name, S> load, 2200 Predicate<S> validate, 2201 Symbol defaultResult) { 2202 //even if a class/package cannot be found in the current module and among packages in modules 2203 //it depends on that are exported for any or this module, the class/package may exist internally 2204 //in some of these modules, or may exist in a module on which this module does not depend. 2205 //Provide better diagnostic in such cases by looking for the class in any module: 2206 Iterable<? extends S> candidates = get.apply(name); 2207 2208 for (S sym : candidates) { 2209 if (validate.test(sym)) 2210 return createInvisibleSymbolError(env, sym); 2211 } 2212 2213 Set<ModuleSymbol> recoverableModules = new HashSet<>(syms.getAllModules()); 2214 2215 recoverableModules.add(syms.unnamedModule); 2216 recoverableModules.remove(env.toplevel.modle); 2217 2218 for (ModuleSymbol ms : recoverableModules) { 2219 //avoid overly eager completing classes from source-based modules, as those 2220 //may not be completable with the current compiler settings: 2221 if (ms.sourceLocation == null) { 2222 if (ms.classLocation == null) { 2223 ms = moduleFinder.findModule(ms); 2224 } 2225 2226 if (ms.kind != ERR) { 2227 S sym = load.apply(ms, name); 2228 2229 if (sym != null && validate.test(sym)) { 2230 return createInvisibleSymbolError(env, sym); 2231 } 2232 } 2233 } 2234 } 2235 2236 return defaultResult; 2237 } 2238 2239 private Symbol createInvisibleSymbolError(Env<AttrContext> env, Symbol sym) { 2240 if (symbolPackageVisible(env, sym)) { 2241 return new AccessError(env, null, sym); 2242 } else { 2243 return new InvisibleSymbolError(env, false, sym); 2244 } 2245 } 2246 2247 private boolean symbolPackageVisible(Env<AttrContext> env, Symbol sym) { 2248 ModuleSymbol envMod = env.toplevel.modle; 2249 PackageSymbol symPack = sym.packge(); 2250 return envMod == symPack.modle || 2251 envMod.visiblePackages.containsKey(symPack.fullname); 2252 } 2253 2254 /** 2255 * Find a type declared in a scope (not inherited). Return null 2256 * if none is found. 2257 * @param env The current environment. 2258 * @param site The original type from where the selection takes 2259 * place. 2260 * @param name The type's name. 2261 * @param c The class to search for the member type. This is 2262 * always a superclass or implemented interface of 2263 * site's class. 2264 */ 2265 Symbol findImmediateMemberType(Env<AttrContext> env, 2266 Type site, 2267 Name name, 2268 TypeSymbol c) { 2269 for (Symbol sym : c.members().getSymbolsByName(name)) { 2270 if (sym.kind == TYP) { 2271 return isAccessible(env, site, sym) 2272 ? sym 2273 : new AccessError(env, site, sym); 2274 } 2275 } 2276 return typeNotFound; 2277 } 2278 2279 /** Find a member type inherited from a superclass or interface. 2280 * @param env The current environment. 2281 * @param site The original type from where the selection takes 2282 * place. 2283 * @param name The type's name. 2284 * @param c The class to search for the member type. This is 2285 * always a superclass or implemented interface of 2286 * site's class. 2287 */ 2288 Symbol findInheritedMemberType(Env<AttrContext> env, 2289 Type site, 2290 Name name, 2291 TypeSymbol c) { 2292 Symbol bestSoFar = typeNotFound; 2293 Symbol sym; 2294 Type st = types.supertype(c.type); 2295 if (st != null && st.hasTag(CLASS)) { 2296 sym = findMemberType(env, site, name, st.tsym); 2297 bestSoFar = bestOf(bestSoFar, sym); 2298 } 2299 for (List<Type> l = types.interfaces(c.type); 2300 bestSoFar.kind != AMBIGUOUS && l.nonEmpty(); 2301 l = l.tail) { 2302 sym = findMemberType(env, site, name, l.head.tsym); 2303 if (!bestSoFar.kind.isResolutionError() && 2304 !sym.kind.isResolutionError() && 2305 sym.owner != bestSoFar.owner) 2306 bestSoFar = new AmbiguityError(bestSoFar, sym); 2307 else 2308 bestSoFar = bestOf(bestSoFar, sym); 2309 } 2310 return bestSoFar; 2311 } 2312 2313 /** Find qualified member type. 2314 * @param env The current environment. 2315 * @param site The original type from where the selection takes 2316 * place. 2317 * @param name The type's name. 2318 * @param c The class to search for the member type. This is 2319 * always a superclass or implemented interface of 2320 * site's class. 2321 */ 2322 Symbol findMemberType(Env<AttrContext> env, 2323 Type site, 2324 Name name, 2325 TypeSymbol c) { 2326 return findMemberTypeInternal(env,site, name, c); 2327 } 2328 2329 /** Find qualified member type. 2330 * @param env The current environment. 2331 * @param site The original type from where the selection takes 2332 * place. 2333 * @param name The type's name. 2334 * @param c The class to search for the member type. This is 2335 * always a superclass or implemented interface of 2336 * site's class. 2337 */ 2338 Symbol findMemberTypeInternal(Env<AttrContext> env, 2339 Type site, 2340 Name name, 2341 TypeSymbol c) { 2342 Symbol sym = findImmediateMemberType(env, site, name, c); 2343 2344 if (sym != typeNotFound) 2345 return sym; 2346 2347 return findInheritedMemberType(env, site, name, c); 2348 2349 } 2350 2351 /** Find a global type in given scope and load corresponding class. 2352 * @param env The current environment. 2353 * @param scope The scope in which to look for the type. 2354 * @param name The type's name. 2355 */ 2356 Symbol findGlobalType(Env<AttrContext> env, Scope scope, Name name, RecoveryLoadClass recoveryLoadClass) { 2357 Symbol bestSoFar = typeNotFound; 2358 for (Symbol s : scope.getSymbolsByName(name)) { 2359 Symbol sym = loadClass(env, s.flatName(), recoveryLoadClass); 2360 if (bestSoFar.kind == TYP && sym.kind == TYP && 2361 bestSoFar != sym) 2362 return new AmbiguityError(bestSoFar, sym); 2363 else 2364 bestSoFar = bestOf(bestSoFar, sym); 2365 } 2366 return bestSoFar; 2367 } 2368 2369 Symbol findTypeVar(Env<AttrContext> env, Name name, boolean staticOnly) { 2370 for (Symbol sym : env.info.scope.getSymbolsByName(name)) { 2371 if (sym.kind == TYP) { 2372 if (sym.type.hasTag(TYPEVAR) && 2373 (staticOnly || (isStatic(env) && sym.owner.kind == TYP))) 2374 // if staticOnly is set, it means that we have recursed through a static declaration, 2375 // so type variable symbols should not be accessible. If staticOnly is unset, but 2376 // we are in a static declaration (field or method), we should not allow type-variables 2377 // defined in the enclosing class to "leak" into this context. 2378 return new StaticError(sym); 2379 return sym; 2380 } 2381 } 2382 return typeNotFound; 2383 } 2384 2385 /** Find an unqualified type symbol. 2386 * @param env The current environment. 2387 * @param name The type's name. 2388 */ 2389 Symbol findType(Env<AttrContext> env, Name name) { 2390 return findTypeInternal(env, name); 2391 } 2392 2393 /** Find an unqualified type symbol. 2394 * @param env The current environment. 2395 * @param name The type's name. 2396 */ 2397 Symbol findTypeInternal(Env<AttrContext> env, Name name) { 2398 if (name == names.empty) 2399 return typeNotFound; // do not allow inadvertent "lookup" of anonymous types 2400 Symbol bestSoFar = typeNotFound; 2401 Symbol sym; 2402 boolean staticOnly = false; 2403 for (Env<AttrContext> env1 = env; env1.outer != null; env1 = env1.outer) { 2404 // First, look for a type variable and the first member type 2405 final Symbol tyvar = findTypeVar(env1, name, staticOnly); 2406 if (isStatic(env1)) staticOnly = true; 2407 sym = findImmediateMemberType(env1, env1.enclClass.sym.type, 2408 name, env1.enclClass.sym); 2409 2410 // Return the type variable if we have it, and have no 2411 // immediate member, OR the type variable is for a method. 2412 if (tyvar != typeNotFound) { 2413 if (env.baseClause || sym == typeNotFound || 2414 (tyvar.kind == TYP && tyvar.exists() && 2415 tyvar.owner.kind == MTH)) { 2416 return tyvar; 2417 } 2418 } 2419 2420 // If the environment is a class def, finish up, 2421 // otherwise, do the entire findMemberType 2422 if (sym == typeNotFound) 2423 sym = findInheritedMemberType(env1, env1.enclClass.sym.type, 2424 name, env1.enclClass.sym); 2425 2426 if (staticOnly && sym.kind == TYP && 2427 sym.type.hasTag(CLASS) && 2428 sym.type.getEnclosingType().hasTag(CLASS) && 2429 env1.enclClass.sym.type.isParameterized() && 2430 sym.type.getEnclosingType().isParameterized()) 2431 return new StaticError(sym); 2432 else if (sym.exists()) return sym; 2433 else bestSoFar = bestOf(bestSoFar, sym); 2434 2435 JCClassDecl encl = env1.baseClause ? (JCClassDecl)env1.tree : env1.enclClass; 2436 if ((encl.sym.flags() & STATIC) != 0) 2437 staticOnly = true; 2438 } 2439 2440 if (!env.tree.hasTag(IMPORT)) { 2441 sym = findGlobalType(env, env.toplevel.namedImportScope, name, namedImportScopeRecovery); 2442 if (sym.exists()) return sym; 2443 else bestSoFar = bestOf(bestSoFar, sym); 2444 2445 sym = findGlobalType(env, env.toplevel.toplevelScope, name, noRecovery); 2446 if (sym.exists()) return sym; 2447 else bestSoFar = bestOf(bestSoFar, sym); 2448 2449 sym = findGlobalType(env, env.toplevel.packge.members(), name, noRecovery); 2450 if (sym.exists()) return sym; 2451 else bestSoFar = bestOf(bestSoFar, sym); 2452 2453 sym = findGlobalType(env, env.toplevel.starImportScope, name, starImportScopeRecovery); 2454 if (sym.exists()) return sym; 2455 else bestSoFar = bestOf(bestSoFar, sym); 2456 } 2457 2458 return bestSoFar; 2459 } 2460 2461 /** Find an unqualified identifier which matches a specified kind set. 2462 * @param pos position on which report warnings, if any; 2463 * null warnings should not be reported 2464 * @param env The current environment. 2465 * @param name The identifier's name. 2466 * @param kind Indicates the possible symbol kinds 2467 * (a subset of VAL, TYP, PCK). 2468 */ 2469 Symbol findIdent(DiagnosticPosition pos, Env<AttrContext> env, Name name, KindSelector kind) { 2470 return checkNonExistentType(checkRestrictedType(pos, findIdentInternal(env, name, kind), name)); 2471 } 2472 2473 Symbol findIdentInternal(Env<AttrContext> env, Name name, KindSelector kind) { 2474 Symbol bestSoFar = typeNotFound; 2475 Symbol sym; 2476 2477 if (kind.contains(KindSelector.VAL)) { 2478 sym = findVar(env, name); 2479 if (sym.exists()) return sym; 2480 else bestSoFar = bestOf(bestSoFar, sym); 2481 } 2482 2483 if (kind.contains(KindSelector.TYP)) { 2484 sym = findType(env, name); 2485 2486 if (sym.exists()) return sym; 2487 else bestSoFar = bestOf(bestSoFar, sym); 2488 } 2489 2490 if (kind.contains(KindSelector.PCK)) 2491 return lookupPackage(env, name); 2492 else return bestSoFar; 2493 } 2494 2495 /** Find an identifier in a package which matches a specified kind set. 2496 * @param pos position on which report warnings, if any; 2497 * null warnings should not be reported 2498 * @param env The current environment. 2499 * @param name The identifier's name. 2500 * @param kind Indicates the possible symbol kinds 2501 * (a nonempty subset of TYP, PCK). 2502 */ 2503 Symbol findIdentInPackage(DiagnosticPosition pos, 2504 Env<AttrContext> env, TypeSymbol pck, 2505 Name name, KindSelector kind) { 2506 return checkNonExistentType(checkRestrictedType(pos, findIdentInPackageInternal(env, pck, name, kind), name)); 2507 } 2508 2509 Symbol findIdentInPackageInternal(Env<AttrContext> env, TypeSymbol pck, 2510 Name name, KindSelector kind) { 2511 Name fullname = TypeSymbol.formFullName(name, pck); 2512 Symbol bestSoFar = typeNotFound; 2513 if (kind.contains(KindSelector.TYP)) { 2514 RecoveryLoadClass recoveryLoadClass = 2515 allowModules && !kind.contains(KindSelector.PCK) && 2516 !pck.exists() && !env.info.attributionMode.isSpeculative ? 2517 doRecoveryLoadClass : noRecovery; 2518 Symbol sym = loadClass(env, fullname, recoveryLoadClass); 2519 if (sym.exists()) { 2520 // don't allow programs to use flatnames 2521 if (name == sym.name) return sym; 2522 } 2523 else bestSoFar = bestOf(bestSoFar, sym); 2524 } 2525 if (kind.contains(KindSelector.PCK)) { 2526 return lookupPackage(env, fullname); 2527 } 2528 return bestSoFar; 2529 } 2530 2531 /** Find an identifier among the members of a given type `site'. 2532 * @param pos position on which report warnings, if any; 2533 * null warnings should not be reported 2534 * @param env The current environment. 2535 * @param site The type containing the symbol to be found. 2536 * @param name The identifier's name. 2537 * @param kind Indicates the possible symbol kinds 2538 * (a subset of VAL, TYP). 2539 */ 2540 Symbol findIdentInType(DiagnosticPosition pos, 2541 Env<AttrContext> env, Type site, 2542 Name name, KindSelector kind) { 2543 return checkNonExistentType(checkRestrictedType(pos, findIdentInTypeInternal(env, site, name, kind), name)); 2544 } 2545 2546 private Symbol checkNonExistentType(Symbol symbol) { 2547 /* Guard against returning a type is not on the class path of the current compilation, 2548 * but *was* on the class path of a separate compilation that produced a class file 2549 * that is on the class path of the current compilation. Such a type will fail completion 2550 * but the completion failure may have been silently swallowed (e.g. missing annotation types) 2551 * with an error stub symbol lingering in the symbol tables. 2552 */ 2553 return symbol instanceof ClassSymbol c && c.type.isErroneous() && c.classfile == null ? typeNotFound : symbol; 2554 } 2555 2556 Symbol findIdentInTypeInternal(Env<AttrContext> env, Type site, 2557 Name name, KindSelector kind) { 2558 Symbol bestSoFar = typeNotFound; 2559 Symbol sym; 2560 if (kind.contains(KindSelector.VAL)) { 2561 sym = findField(env, site, name, site.tsym); 2562 if (sym.exists()) return sym; 2563 else bestSoFar = bestOf(bestSoFar, sym); 2564 } 2565 2566 if (kind.contains(KindSelector.TYP)) { 2567 sym = findMemberType(env, site, name, site.tsym); 2568 if (sym.exists()) return sym; 2569 else bestSoFar = bestOf(bestSoFar, sym); 2570 } 2571 return bestSoFar; 2572 } 2573 2574 private Symbol checkRestrictedType(DiagnosticPosition pos, Symbol bestSoFar, Name name) { 2575 if (bestSoFar.kind == TYP || bestSoFar.kind == ABSENT_TYP) { 2576 if (allowLocalVariableTypeInference && name.equals(names.var)) { 2577 bestSoFar = new BadRestrictedTypeError(names.var); 2578 } else if (name.equals(names.yield)) { 2579 if (allowYieldStatement) { 2580 bestSoFar = new BadRestrictedTypeError(names.yield); 2581 } else if (pos != null) { 2582 log.warning(pos, Warnings.IllegalRefToRestrictedType(names.yield)); 2583 } 2584 } 2585 } 2586 return bestSoFar; 2587 } 2588 2589 /* *************************************************************************** 2590 * Access checking 2591 * The following methods convert ResolveErrors to ErrorSymbols, issuing 2592 * an error message in the process 2593 ****************************************************************************/ 2594 2595 /** If `sym' is a bad symbol: report error and return errSymbol 2596 * else pass through unchanged, 2597 * additional arguments duplicate what has been used in trying to find the 2598 * symbol {@literal (--> flyweight pattern)}. This improves performance since we 2599 * expect misses to happen frequently. 2600 * 2601 * @param sym The symbol that was found, or a ResolveError. 2602 * @param pos The position to use for error reporting. 2603 * @param location The symbol the served as a context for this lookup 2604 * @param site The original type from where the selection took place. 2605 * @param name The symbol's name. 2606 * @param qualified Did we get here through a qualified expression resolution? 2607 * @param argtypes The invocation's value arguments, 2608 * if we looked for a method. 2609 * @param typeargtypes The invocation's type arguments, 2610 * if we looked for a method. 2611 * @param logResolveHelper helper class used to log resolve errors 2612 */ 2613 Symbol accessInternal(Symbol sym, 2614 DiagnosticPosition pos, 2615 Symbol location, 2616 Type site, 2617 Name name, 2618 boolean qualified, 2619 List<Type> argtypes, 2620 List<Type> typeargtypes, 2621 LogResolveHelper logResolveHelper) { 2622 if (sym.kind.isResolutionError()) { 2623 ResolveError errSym = (ResolveError)sym.baseSymbol(); 2624 sym = errSym.access(name, qualified ? site.tsym : syms.noSymbol); 2625 argtypes = logResolveHelper.getArgumentTypes(errSym, sym, name, argtypes); 2626 if (logResolveHelper.resolveDiagnosticNeeded(site, argtypes, typeargtypes)) { 2627 logResolveError(errSym, pos, location, site, name, argtypes, typeargtypes); 2628 } 2629 } 2630 return sym; 2631 } 2632 2633 /** 2634 * Variant of the generalized access routine, to be used for generating method 2635 * resolution diagnostics 2636 */ 2637 Symbol accessMethod(Symbol sym, 2638 DiagnosticPosition pos, 2639 Symbol location, 2640 Type site, 2641 Name name, 2642 boolean qualified, 2643 List<Type> argtypes, 2644 List<Type> typeargtypes) { 2645 return accessInternal(sym, pos, location, site, name, qualified, argtypes, typeargtypes, methodLogResolveHelper); 2646 } 2647 2648 /** Same as original accessMethod(), but without location. 2649 */ 2650 Symbol accessMethod(Symbol sym, 2651 DiagnosticPosition pos, 2652 Type site, 2653 Name name, 2654 boolean qualified, 2655 List<Type> argtypes, 2656 List<Type> typeargtypes) { 2657 return accessMethod(sym, pos, site.tsym, site, name, qualified, argtypes, typeargtypes); 2658 } 2659 2660 /** 2661 * Variant of the generalized access routine, to be used for generating variable, 2662 * type resolution diagnostics 2663 */ 2664 Symbol accessBase(Symbol sym, 2665 DiagnosticPosition pos, 2666 Symbol location, 2667 Type site, 2668 Name name, 2669 boolean qualified) { 2670 return accessInternal(sym, pos, location, site, name, qualified, List.nil(), null, basicLogResolveHelper); 2671 } 2672 2673 /** Same as original accessBase(), but without location. 2674 */ 2675 Symbol accessBase(Symbol sym, 2676 DiagnosticPosition pos, 2677 Type site, 2678 Name name, 2679 boolean qualified) { 2680 return accessBase(sym, pos, site.tsym, site, name, qualified); 2681 } 2682 2683 interface LogResolveHelper { 2684 boolean resolveDiagnosticNeeded(Type site, List<Type> argtypes, List<Type> typeargtypes); 2685 List<Type> getArgumentTypes(ResolveError errSym, Symbol accessedSym, Name name, List<Type> argtypes); 2686 } 2687 2688 LogResolveHelper basicLogResolveHelper = new LogResolveHelper() { 2689 public boolean resolveDiagnosticNeeded(Type site, List<Type> argtypes, List<Type> typeargtypes) { 2690 return !site.isErroneous(); 2691 } 2692 public List<Type> getArgumentTypes(ResolveError errSym, Symbol accessedSym, Name name, List<Type> argtypes) { 2693 return argtypes; 2694 } 2695 }; 2696 2697 LogResolveHelper silentLogResolveHelper = new LogResolveHelper() { 2698 public boolean resolveDiagnosticNeeded(Type site, List<Type> argtypes, List<Type> typeargtypes) { 2699 return false; 2700 } 2701 public List<Type> getArgumentTypes(ResolveError errSym, Symbol accessedSym, Name name, List<Type> argtypes) { 2702 return argtypes; 2703 } 2704 }; 2705 2706 LogResolveHelper methodLogResolveHelper = new LogResolveHelper() { 2707 public boolean resolveDiagnosticNeeded(Type site, List<Type> argtypes, List<Type> typeargtypes) { 2708 return !site.isErroneous() && 2709 !Type.isErroneous(argtypes) && 2710 (typeargtypes == null || !Type.isErroneous(typeargtypes)); 2711 } 2712 public List<Type> getArgumentTypes(ResolveError errSym, Symbol accessedSym, Name name, List<Type> argtypes) { 2713 return argtypes.map(new ResolveDeferredRecoveryMap(AttrMode.SPECULATIVE, accessedSym, currentResolutionContext.step)); 2714 } 2715 }; 2716 2717 class ResolveDeferredRecoveryMap extends DeferredAttr.RecoveryDeferredTypeMap { 2718 2719 public ResolveDeferredRecoveryMap(AttrMode mode, Symbol msym, MethodResolutionPhase step) { 2720 deferredAttr.super(mode, msym, step); 2721 } 2722 2723 @Override 2724 protected Type typeOf(DeferredType dt, Type pt) { 2725 Type res = super.typeOf(dt, pt); 2726 if (!res.isErroneous()) { 2727 switch (TreeInfo.skipParens(dt.tree).getTag()) { 2728 case LAMBDA: 2729 case REFERENCE: 2730 return dt; 2731 case CONDEXPR: 2732 return res == Type.recoveryType ? 2733 dt : res; 2734 } 2735 } 2736 return res; 2737 } 2738 } 2739 2740 /** Check that sym is not an abstract method. 2741 */ 2742 void checkNonAbstract(DiagnosticPosition pos, Symbol sym) { 2743 if ((sym.flags() & ABSTRACT) != 0 && (sym.flags() & DEFAULT) == 0) 2744 log.error(pos, 2745 Errors.AbstractCantBeAccessedDirectly(kindName(sym),sym, sym.location())); 2746 } 2747 2748 /* *************************************************************************** 2749 * Name resolution 2750 * Naming conventions are as for symbol lookup 2751 * Unlike the find... methods these methods will report access errors 2752 ****************************************************************************/ 2753 2754 /** Resolve an unqualified (non-method) identifier. 2755 * @param pos The position to use for error reporting. 2756 * @param env The environment current at the identifier use. 2757 * @param name The identifier's name. 2758 * @param kind The set of admissible symbol kinds for the identifier. 2759 */ 2760 Symbol resolveIdent(DiagnosticPosition pos, Env<AttrContext> env, 2761 Name name, KindSelector kind) { 2762 return accessBase( 2763 findIdent(pos, env, name, kind), 2764 pos, env.enclClass.sym.type, name, false); 2765 } 2766 2767 /** Resolve an unqualified method identifier. 2768 * @param pos The position to use for error reporting. 2769 * @param env The environment current at the method invocation. 2770 * @param name The identifier's name. 2771 * @param argtypes The types of the invocation's value arguments. 2772 * @param typeargtypes The types of the invocation's type arguments. 2773 */ 2774 Symbol resolveMethod(DiagnosticPosition pos, 2775 Env<AttrContext> env, 2776 Name name, 2777 List<Type> argtypes, 2778 List<Type> typeargtypes) { 2779 return lookupMethod(env, pos, env.enclClass.sym, resolveMethodCheck, 2780 new BasicLookupHelper(name, env.enclClass.sym.type, argtypes, typeargtypes) { 2781 @Override 2782 Symbol doLookup(Env<AttrContext> env, MethodResolutionPhase phase) { 2783 return findFun(env, name, argtypes, typeargtypes, 2784 phase.isBoxingRequired(), 2785 phase.isVarargsRequired()); 2786 }}); 2787 } 2788 2789 /** Resolve a qualified method identifier 2790 * @param pos The position to use for error reporting. 2791 * @param env The environment current at the method invocation. 2792 * @param site The type of the qualifying expression, in which 2793 * identifier is searched. 2794 * @param name The identifier's name. 2795 * @param argtypes The types of the invocation's value arguments. 2796 * @param typeargtypes The types of the invocation's type arguments. 2797 */ 2798 Symbol resolveQualifiedMethod(DiagnosticPosition pos, Env<AttrContext> env, 2799 Type site, Name name, List<Type> argtypes, 2800 List<Type> typeargtypes) { 2801 return resolveQualifiedMethod(pos, env, site.tsym, site, name, argtypes, typeargtypes); 2802 } 2803 Symbol resolveQualifiedMethod(DiagnosticPosition pos, Env<AttrContext> env, 2804 Symbol location, Type site, Name name, List<Type> argtypes, 2805 List<Type> typeargtypes) { 2806 return resolveQualifiedMethod(new MethodResolutionContext(), pos, env, location, site, name, argtypes, typeargtypes); 2807 } 2808 private Symbol resolveQualifiedMethod(MethodResolutionContext resolveContext, 2809 DiagnosticPosition pos, Env<AttrContext> env, 2810 Symbol location, Type site, Name name, List<Type> argtypes, 2811 List<Type> typeargtypes) { 2812 return lookupMethod(env, pos, location, resolveContext, new BasicLookupHelper(name, site, argtypes, typeargtypes) { 2813 @Override 2814 Symbol doLookup(Env<AttrContext> env, MethodResolutionPhase phase) { 2815 return findMethod(env, site, name, argtypes, typeargtypes, 2816 phase.isBoxingRequired(), 2817 phase.isVarargsRequired()); 2818 } 2819 @Override 2820 Symbol access(Env<AttrContext> env, DiagnosticPosition pos, Symbol location, Symbol sym) { 2821 if (sym.kind.isResolutionError()) { 2822 sym = super.access(env, pos, location, sym); 2823 } else { 2824 MethodSymbol msym = (MethodSymbol)sym; 2825 if ((msym.flags() & SIGNATURE_POLYMORPHIC) != 0) { 2826 env.info.pendingResolutionPhase = BASIC; 2827 return findPolymorphicSignatureInstance(env, sym, argtypes); 2828 } 2829 } 2830 return sym; 2831 } 2832 }); 2833 } 2834 2835 /** Find or create an implicit method of exactly the given type (after erasure). 2836 * Searches in a side table, not the main scope of the site. 2837 * This emulates the lookup process required by JSR 292 in JVM. 2838 * @param env Attribution environment 2839 * @param spMethod signature polymorphic method - i.e. MH.invokeExact 2840 * @param argtypes The required argument types 2841 */ 2842 Symbol findPolymorphicSignatureInstance(Env<AttrContext> env, 2843 final Symbol spMethod, 2844 List<Type> argtypes) { 2845 Type mtype = infer.instantiatePolymorphicSignatureInstance(env, 2846 (MethodSymbol)spMethod, currentResolutionContext, argtypes); 2847 return findPolymorphicSignatureInstance(spMethod, mtype); 2848 } 2849 2850 Symbol findPolymorphicSignatureInstance(final Symbol spMethod, 2851 Type mtype) { 2852 for (Symbol sym : polymorphicSignatureScope.getSymbolsByName(spMethod.name)) { 2853 // Check that there is already a method symbol for the method 2854 // type and owner 2855 if (types.isSameType(mtype, sym.type) && 2856 spMethod.owner == sym.owner) { 2857 return sym; 2858 } 2859 } 2860 2861 Type spReturnType = spMethod.asType().getReturnType(); 2862 if (types.isSameType(spReturnType, syms.objectType)) { 2863 // Polymorphic return, pass through mtype 2864 } else if (!types.isSameType(spReturnType, mtype.getReturnType())) { 2865 // Retain the sig poly method's return type, which differs from that of mtype 2866 // Will result in an incompatible return type error 2867 mtype = new MethodType(mtype.getParameterTypes(), 2868 spReturnType, 2869 mtype.getThrownTypes(), 2870 syms.methodClass); 2871 } 2872 2873 // Create the desired method 2874 // Retain static modifier is to support invocations to 2875 // MethodHandle.linkTo* methods 2876 long flags = ABSTRACT | HYPOTHETICAL | 2877 spMethod.flags() & (Flags.AccessFlags | Flags.STATIC); 2878 Symbol msym = new MethodSymbol(flags, spMethod.name, mtype, spMethod.owner) { 2879 @Override 2880 public Symbol baseSymbol() { 2881 return spMethod; 2882 } 2883 }; 2884 if (!mtype.isErroneous()) { // Cache only if kosher. 2885 polymorphicSignatureScope.enter(msym); 2886 } 2887 return msym; 2888 } 2889 2890 /** Resolve a qualified method identifier, throw a fatal error if not 2891 * found. 2892 * @param pos The position to use for error reporting. 2893 * @param env The environment current at the method invocation. 2894 * @param site The type of the qualifying expression, in which 2895 * identifier is searched. 2896 * @param name The identifier's name. 2897 * @param argtypes The types of the invocation's value arguments. 2898 * @param typeargtypes The types of the invocation's type arguments. 2899 */ 2900 public MethodSymbol resolveInternalMethod(DiagnosticPosition pos, Env<AttrContext> env, 2901 Type site, Name name, 2902 List<Type> argtypes, 2903 List<Type> typeargtypes) { 2904 MethodResolutionContext resolveContext = new MethodResolutionContext(); 2905 resolveContext.internalResolution = true; 2906 Symbol sym = resolveQualifiedMethod(resolveContext, pos, env, site.tsym, 2907 site, name, argtypes, typeargtypes); 2908 if (sym.kind == MTH) return (MethodSymbol)sym; 2909 else throw new FatalError( 2910 diags.fragment(Fragments.FatalErrCantLocateMeth(name))); 2911 } 2912 2913 /** Resolve constructor. 2914 * @param pos The position to use for error reporting. 2915 * @param env The environment current at the constructor invocation. 2916 * @param site The type of class for which a constructor is searched. 2917 * @param argtypes The types of the constructor invocation's value 2918 * arguments. 2919 * @param typeargtypes The types of the constructor invocation's type 2920 * arguments. 2921 */ 2922 Symbol resolveConstructor(DiagnosticPosition pos, 2923 Env<AttrContext> env, 2924 Type site, 2925 List<Type> argtypes, 2926 List<Type> typeargtypes) { 2927 return resolveConstructor(new MethodResolutionContext(), pos, env, site, argtypes, typeargtypes); 2928 } 2929 2930 private Symbol resolveConstructor(MethodResolutionContext resolveContext, 2931 final DiagnosticPosition pos, 2932 Env<AttrContext> env, 2933 Type site, 2934 List<Type> argtypes, 2935 List<Type> typeargtypes) { 2936 Name constructorName = site.tsym.isConcreteValueClass() ? names.vnew : names.init; 2937 return lookupMethod(env, pos, site.tsym, resolveContext, new BasicLookupHelper(constructorName, site, argtypes, typeargtypes) { 2938 @Override 2939 Symbol doLookup(Env<AttrContext> env, MethodResolutionPhase phase) { 2940 return findConstructor(pos, env, site, argtypes, typeargtypes, 2941 phase.isBoxingRequired(), 2942 phase.isVarargsRequired()); 2943 } 2944 }); 2945 } 2946 2947 /** Resolve a constructor, throw a fatal error if not found. 2948 * @param pos The position to use for error reporting. 2949 * @param env The environment current at the method invocation. 2950 * @param site The type to be constructed. 2951 * @param argtypes The types of the invocation's value arguments. 2952 * @param typeargtypes The types of the invocation's type arguments. 2953 */ 2954 public MethodSymbol resolveInternalConstructor(DiagnosticPosition pos, Env<AttrContext> env, 2955 Type site, 2956 List<Type> argtypes, 2957 List<Type> typeargtypes) { 2958 MethodResolutionContext resolveContext = new MethodResolutionContext(); 2959 resolveContext.internalResolution = true; 2960 Symbol sym = resolveConstructor(resolveContext, pos, env, site, argtypes, typeargtypes); 2961 if (sym.kind == MTH) return (MethodSymbol)sym; 2962 else throw new FatalError( 2963 diags.fragment(Fragments.FatalErrCantLocateCtor(site))); 2964 } 2965 2966 Symbol findConstructor(DiagnosticPosition pos, Env<AttrContext> env, 2967 Type site, List<Type> argtypes, 2968 List<Type> typeargtypes, 2969 boolean allowBoxing, 2970 boolean useVarargs) { 2971 Name constructorName = site.tsym.isConcreteValueClass() ? names.vnew : names.init; 2972 Symbol sym = findMethod(env, site, 2973 constructorName, argtypes, 2974 typeargtypes, allowBoxing, 2975 useVarargs); 2976 chk.checkDeprecated(pos, env.info.scope.owner, sym); 2977 chk.checkPreview(pos, env.info.scope.owner, sym); 2978 return sym; 2979 } 2980 2981 /** Resolve constructor using diamond inference. 2982 * @param pos The position to use for error reporting. 2983 * @param env The environment current at the constructor invocation. 2984 * @param site The type of class for which a constructor is searched. 2985 * The scope of this class has been touched in attribution. 2986 * @param argtypes The types of the constructor invocation's value 2987 * arguments. 2988 * @param typeargtypes The types of the constructor invocation's type 2989 * arguments. 2990 */ 2991 Symbol resolveDiamond(DiagnosticPosition pos, 2992 Env<AttrContext> env, 2993 Type site, 2994 List<Type> argtypes, 2995 List<Type> typeargtypes) { 2996 Name constructorName = allowValueClasses && site.tsym.isConcreteValueClass() ? names.vnew : names.init; 2997 return lookupMethod(env, pos, site.tsym, resolveMethodCheck, 2998 new BasicLookupHelper(constructorName, site, argtypes, typeargtypes) { 2999 @Override 3000 Symbol doLookup(Env<AttrContext> env, MethodResolutionPhase phase) { 3001 return findDiamond(pos, env, site, argtypes, typeargtypes, 3002 phase.isBoxingRequired(), 3003 phase.isVarargsRequired()); 3004 } 3005 @Override 3006 Symbol access(Env<AttrContext> env, DiagnosticPosition pos, Symbol location, Symbol sym) { 3007 if (sym.kind.isResolutionError()) { 3008 if (sym.kind != WRONG_MTH && 3009 sym.kind != WRONG_MTHS) { 3010 sym = super.access(env, pos, location, sym); 3011 } else { 3012 sym = new DiamondError(sym, currentResolutionContext); 3013 sym = accessMethod(sym, pos, site, constructorName, true, argtypes, typeargtypes); 3014 env.info.pendingResolutionPhase = currentResolutionContext.step; 3015 } 3016 } 3017 return sym; 3018 }}); 3019 } 3020 3021 /** Find the constructor using diamond inference and do some checks(deprecated and preview). 3022 * @param pos The position to use for error reporting. 3023 * @param env The environment current at the constructor invocation. 3024 * @param site The type of class for which a constructor is searched. 3025 * The scope of this class has been touched in attribution. 3026 * @param argtypes The types of the constructor invocation's value arguments. 3027 * @param typeargtypes The types of the constructor invocation's type arguments. 3028 * @param allowBoxing Allow boxing conversions of arguments. 3029 * @param useVarargs Box trailing arguments into an array for varargs. 3030 */ 3031 private Symbol findDiamond(DiagnosticPosition pos, 3032 Env<AttrContext> env, 3033 Type site, 3034 List<Type> argtypes, 3035 List<Type> typeargtypes, 3036 boolean allowBoxing, 3037 boolean useVarargs) { 3038 Symbol sym = findDiamond(env, site, argtypes, typeargtypes, allowBoxing, useVarargs); 3039 chk.checkDeprecated(pos, env.info.scope.owner, sym); 3040 chk.checkPreview(pos, env.info.scope.owner, sym); 3041 return sym; 3042 } 3043 3044 /** This method scans all the constructor symbol in a given class scope - 3045 * assuming that the original scope contains a constructor of the kind: 3046 * {@code Foo(X x, Y y)}, where X,Y are class type-variables declared in Foo, 3047 * a method check is executed against the modified constructor type: 3048 * {@code <X,Y>Foo<X,Y>(X x, Y y)}. This is crucial in order to enable diamond 3049 * inference. The inferred return type of the synthetic constructor IS 3050 * the inferred type for the diamond operator. 3051 */ 3052 private Symbol findDiamond(Env<AttrContext> env, 3053 Type site, 3054 List<Type> argtypes, 3055 List<Type> typeargtypes, 3056 boolean allowBoxing, 3057 boolean useVarargs) { 3058 Symbol bestSoFar = methodNotFound; 3059 TypeSymbol tsym = site.tsym.isInterface() ? syms.objectType.tsym : site.tsym; 3060 Name constructorName = site.tsym.isConcreteValueClass() ? names.vnew : names.init; 3061 for (final Symbol sym : tsym.members().getSymbolsByName(constructorName)) { 3062 //- System.out.println(" e " + e.sym); 3063 if (sym.kind == MTH && 3064 (sym.flags_field & SYNTHETIC) == 0) { 3065 List<Type> oldParams = sym.type.hasTag(FORALL) ? 3066 ((ForAll)sym.type).tvars : 3067 List.nil(); 3068 Type constrType = new ForAll(site.tsym.type.getTypeArguments().appendList(oldParams), 3069 types.createMethodTypeWithReturn(sym.type.asMethodType(), site)); 3070 MethodSymbol newConstr = new MethodSymbol(sym.flags(), constructorName, constrType, site.tsym) { 3071 @Override 3072 public Symbol baseSymbol() { 3073 return sym; 3074 } 3075 }; 3076 bestSoFar = selectBest(env, site, argtypes, typeargtypes, 3077 newConstr, 3078 bestSoFar, 3079 allowBoxing, 3080 useVarargs); 3081 } 3082 } 3083 return bestSoFar; 3084 } 3085 3086 Symbol getMemberReference(DiagnosticPosition pos, 3087 Env<AttrContext> env, 3088 JCMemberReference referenceTree, 3089 Type site, 3090 Name name) { 3091 3092 site = types.capture(site); 3093 3094 ReferenceLookupHelper lookupHelper = makeReferenceLookupHelper( 3095 referenceTree, site, name, List.nil(), null, VARARITY); 3096 3097 Env<AttrContext> newEnv = env.dup(env.tree, env.info.dup()); 3098 Symbol sym = lookupMethod(newEnv, env.tree.pos(), site.tsym, 3099 nilMethodCheck, lookupHelper); 3100 3101 env.info.pendingResolutionPhase = newEnv.info.pendingResolutionPhase; 3102 3103 return sym; 3104 } 3105 3106 ReferenceLookupHelper makeReferenceLookupHelper(JCMemberReference referenceTree, 3107 Type site, 3108 Name name, 3109 List<Type> argtypes, 3110 List<Type> typeargtypes, 3111 MethodResolutionPhase maxPhase) { 3112 if (!names.isInitOrVNew(name)) { 3113 //method reference 3114 return new MethodReferenceLookupHelper(referenceTree, name, site, argtypes, typeargtypes, maxPhase); 3115 } else if (site.hasTag(ARRAY)) { 3116 //array constructor reference 3117 return new ArrayConstructorReferenceLookupHelper(referenceTree, site, argtypes, typeargtypes, maxPhase); 3118 } else { 3119 //class constructor reference 3120 return new ConstructorReferenceLookupHelper(referenceTree, site, argtypes, typeargtypes, maxPhase); 3121 } 3122 } 3123 3124 /** 3125 * Resolution of member references is typically done as a single 3126 * overload resolution step, where the argument types A are inferred from 3127 * the target functional descriptor. 3128 * 3129 * If the member reference is a method reference with a type qualifier, 3130 * a two-step lookup process is performed. The first step uses the 3131 * expected argument list A, while the second step discards the first 3132 * type from A (which is treated as a receiver type). 3133 * 3134 * There are two cases in which inference is performed: (i) if the member 3135 * reference is a constructor reference and the qualifier type is raw - in 3136 * which case diamond inference is used to infer a parameterization for the 3137 * type qualifier; (ii) if the member reference is an unbound reference 3138 * where the type qualifier is raw - in that case, during the unbound lookup 3139 * the receiver argument type is used to infer an instantiation for the raw 3140 * qualifier type. 3141 * 3142 * When a multi-step resolution process is exploited, the process of picking 3143 * the resulting symbol is delegated to an helper class {@link com.sun.tools.javac.comp.Resolve.ReferenceChooser}. 3144 * 3145 * This routine returns a pair (T,S), where S is the member reference symbol, 3146 * and T is the type of the class in which S is defined. This is necessary as 3147 * the type T might be dynamically inferred (i.e. if constructor reference 3148 * has a raw qualifier). 3149 */ 3150 Pair<Symbol, ReferenceLookupHelper> resolveMemberReference(Env<AttrContext> env, 3151 JCMemberReference referenceTree, 3152 Type site, 3153 Name name, 3154 List<Type> argtypes, 3155 List<Type> typeargtypes, 3156 Type descriptor, 3157 MethodCheck methodCheck, 3158 InferenceContext inferenceContext, 3159 ReferenceChooser referenceChooser) { 3160 3161 //step 1 - bound lookup 3162 ReferenceLookupHelper boundLookupHelper = makeReferenceLookupHelper( 3163 referenceTree, site, name, argtypes, typeargtypes, VARARITY); 3164 Env<AttrContext> boundEnv = env.dup(env.tree, env.info.dup()); 3165 MethodResolutionContext boundSearchResolveContext = new MethodResolutionContext(); 3166 boundSearchResolveContext.methodCheck = methodCheck; 3167 Symbol boundSym = lookupMethod(boundEnv, env.tree.pos(), 3168 site.tsym, boundSearchResolveContext, boundLookupHelper); 3169 boolean isStaticSelector = TreeInfo.isStaticSelector(referenceTree.expr, names); 3170 ReferenceLookupResult boundRes = new ReferenceLookupResult(boundSym, boundSearchResolveContext, isStaticSelector); 3171 if (dumpMethodReferenceSearchResults) { 3172 dumpMethodReferenceSearchResults(referenceTree, boundSearchResolveContext, boundSym, true); 3173 } 3174 3175 //step 2 - unbound lookup 3176 Symbol unboundSym = methodNotFound; 3177 Env<AttrContext> unboundEnv = env.dup(env.tree, env.info.dup()); 3178 ReferenceLookupHelper unboundLookupHelper = boundLookupHelper.unboundLookup(inferenceContext); 3179 ReferenceLookupResult unboundRes = referenceNotFound; 3180 if (unboundLookupHelper != null) { 3181 MethodResolutionContext unboundSearchResolveContext = 3182 new MethodResolutionContext(); 3183 unboundSearchResolveContext.methodCheck = methodCheck; 3184 unboundSym = lookupMethod(unboundEnv, env.tree.pos(), 3185 site.tsym, unboundSearchResolveContext, unboundLookupHelper); 3186 unboundRes = new ReferenceLookupResult(unboundSym, unboundSearchResolveContext, isStaticSelector); 3187 if (dumpMethodReferenceSearchResults) { 3188 dumpMethodReferenceSearchResults(referenceTree, unboundSearchResolveContext, unboundSym, false); 3189 } 3190 } 3191 3192 //merge results 3193 Pair<Symbol, ReferenceLookupHelper> res; 3194 ReferenceLookupResult bestRes = referenceChooser.result(boundRes, unboundRes); 3195 res = new Pair<>(bestRes.sym, 3196 bestRes == unboundRes ? unboundLookupHelper : boundLookupHelper); 3197 env.info.pendingResolutionPhase = bestRes == unboundRes ? 3198 unboundEnv.info.pendingResolutionPhase : 3199 boundEnv.info.pendingResolutionPhase; 3200 3201 if (!res.fst.kind.isResolutionError()) { 3202 //handle sigpoly method references 3203 MethodSymbol msym = (MethodSymbol)res.fst; 3204 if ((msym.flags() & SIGNATURE_POLYMORPHIC) != 0) { 3205 env.info.pendingResolutionPhase = BASIC; 3206 res = new Pair<>(findPolymorphicSignatureInstance(msym, descriptor), res.snd); 3207 } 3208 } 3209 3210 return res; 3211 } 3212 3213 private void dumpMethodReferenceSearchResults(JCMemberReference referenceTree, 3214 MethodResolutionContext resolutionContext, 3215 Symbol bestSoFar, 3216 boolean bound) { 3217 ListBuffer<JCDiagnostic> subDiags = new ListBuffer<>(); 3218 int pos = 0; 3219 int mostSpecificPos = -1; 3220 for (Candidate c : resolutionContext.candidates) { 3221 if (resolutionContext.step != c.step || !c.isApplicable()) { 3222 continue; 3223 } else { 3224 JCDiagnostic subDiag = null; 3225 if (c.sym.type.hasTag(FORALL)) { 3226 subDiag = diags.fragment(Fragments.PartialInstSig(c.mtype)); 3227 } 3228 3229 String key = subDiag == null ? 3230 "applicable.method.found.2" : 3231 "applicable.method.found.3"; 3232 subDiags.append(diags.fragment(key, pos, 3233 c.sym.isStatic() ? Fragments.Static : Fragments.NonStatic, c.sym, subDiag)); 3234 if (c.sym == bestSoFar) 3235 mostSpecificPos = pos; 3236 pos++; 3237 } 3238 } 3239 JCDiagnostic main = diags.note( 3240 log.currentSource(), 3241 referenceTree, 3242 "method.ref.search.results.multi", 3243 bound ? Fragments.Bound : Fragments.Unbound, 3244 referenceTree.toString(), mostSpecificPos); 3245 JCDiagnostic d = new JCDiagnostic.MultilineDiagnostic(main, subDiags.toList()); 3246 log.report(d); 3247 } 3248 3249 /** 3250 * This class is used to represent a method reference lookup result. It keeps track of two 3251 * things: (i) the symbol found during a method reference lookup and (ii) the static kind 3252 * of the lookup (see {@link com.sun.tools.javac.comp.Resolve.ReferenceLookupResult.StaticKind}). 3253 */ 3254 static class ReferenceLookupResult { 3255 3256 /** 3257 * Static kind associated with a method reference lookup. Erroneous lookups end up with 3258 * the UNDEFINED kind; successful lookups will end up with either STATIC, NON_STATIC, 3259 * depending on whether all applicable candidates are static or non-static methods, 3260 * respectively. If a successful lookup has both static and non-static applicable methods, 3261 * its kind is set to BOTH. 3262 */ 3263 enum StaticKind { 3264 STATIC, 3265 NON_STATIC, 3266 BOTH, 3267 UNDEFINED; 3268 3269 /** 3270 * Retrieve the static kind associated with a given (method) symbol. 3271 */ 3272 static StaticKind from(Symbol s) { 3273 return s.isStatic() ? 3274 STATIC : NON_STATIC; 3275 } 3276 3277 /** 3278 * Merge two static kinds together. 3279 */ 3280 static StaticKind reduce(StaticKind sk1, StaticKind sk2) { 3281 if (sk1 == UNDEFINED) { 3282 return sk2; 3283 } else if (sk2 == UNDEFINED) { 3284 return sk1; 3285 } else { 3286 return sk1 == sk2 ? sk1 : BOTH; 3287 } 3288 } 3289 } 3290 3291 /** The static kind. */ 3292 StaticKind staticKind; 3293 3294 /** The lookup result. */ 3295 Symbol sym; 3296 3297 ReferenceLookupResult(Symbol sym, MethodResolutionContext resolutionContext, boolean isStaticSelector) { 3298 this(sym, staticKind(sym, resolutionContext, isStaticSelector)); 3299 } 3300 3301 private ReferenceLookupResult(Symbol sym, StaticKind staticKind) { 3302 this.staticKind = staticKind; 3303 this.sym = sym; 3304 } 3305 3306 private static StaticKind staticKind(Symbol sym, MethodResolutionContext resolutionContext, boolean isStaticSelector) { 3307 if (sym.kind == MTH && !isStaticSelector) { 3308 return StaticKind.from(sym); 3309 } else if (sym.kind == MTH || sym.kind == AMBIGUOUS) { 3310 return resolutionContext.candidates.stream() 3311 .filter(c -> c.isApplicable() && c.step == resolutionContext.step) 3312 .map(c -> StaticKind.from(c.sym)) 3313 .reduce(StaticKind::reduce) 3314 .orElse(StaticKind.UNDEFINED); 3315 } else { 3316 return StaticKind.UNDEFINED; 3317 } 3318 } 3319 3320 /** 3321 * Does this result corresponds to a successful lookup (i.e. one where a method has been found?) 3322 */ 3323 boolean isSuccess() { 3324 return staticKind != StaticKind.UNDEFINED; 3325 } 3326 3327 /** 3328 * Does this result have given static kind? 3329 */ 3330 boolean hasKind(StaticKind sk) { 3331 return this.staticKind == sk; 3332 } 3333 3334 /** 3335 * Error recovery helper: can this lookup result be ignored (for the purpose of returning 3336 * some 'better' result) ? 3337 */ 3338 boolean canIgnore() { 3339 switch (sym.kind) { 3340 case ABSENT_MTH: 3341 return true; 3342 case WRONG_MTH: 3343 InapplicableSymbolError errSym = 3344 (InapplicableSymbolError)sym.baseSymbol(); 3345 return new Template(MethodCheckDiag.ARITY_MISMATCH.regex()) 3346 .matches(errSym.errCandidate().snd); 3347 case WRONG_MTHS: 3348 InapplicableSymbolsError errSyms = 3349 (InapplicableSymbolsError)sym.baseSymbol(); 3350 return errSyms.filterCandidates(errSyms.mapCandidates()).isEmpty(); 3351 default: 3352 return false; 3353 } 3354 } 3355 3356 static ReferenceLookupResult error(Symbol sym) { 3357 return new ReferenceLookupResult(sym, StaticKind.UNDEFINED); 3358 } 3359 } 3360 3361 /** 3362 * This abstract class embodies the logic that converts one (bound lookup) or two (unbound lookup) 3363 * {@code ReferenceLookupResult} objects into a (@code Symbol), which is then regarded as the 3364 * result of method reference resolution. 3365 */ 3366 abstract class ReferenceChooser { 3367 /** 3368 * Generate a result from a pair of lookup result objects. This method delegates to the 3369 * appropriate result generation routine. 3370 */ 3371 ReferenceLookupResult result(ReferenceLookupResult boundRes, ReferenceLookupResult unboundRes) { 3372 return unboundRes != referenceNotFound ? 3373 unboundResult(boundRes, unboundRes) : 3374 boundResult(boundRes); 3375 } 3376 3377 /** 3378 * Generate a symbol from a given bound lookup result. 3379 */ 3380 abstract ReferenceLookupResult boundResult(ReferenceLookupResult boundRes); 3381 3382 /** 3383 * Generate a symbol from a pair of bound/unbound lookup results. 3384 */ 3385 abstract ReferenceLookupResult unboundResult(ReferenceLookupResult boundRes, ReferenceLookupResult unboundRes); 3386 } 3387 3388 /** 3389 * This chooser implements the selection strategy used during a full lookup; this logic 3390 * is described in JLS SE 8 (15.3.2). 3391 */ 3392 ReferenceChooser basicReferenceChooser = new ReferenceChooser() { 3393 3394 @Override 3395 ReferenceLookupResult boundResult(ReferenceLookupResult boundRes) { 3396 return !boundRes.isSuccess() || boundRes.hasKind(StaticKind.NON_STATIC) ? 3397 boundRes : //the search produces a non-static method 3398 ReferenceLookupResult.error(new BadMethodReferenceError(boundRes.sym, false)); 3399 } 3400 3401 @Override 3402 ReferenceLookupResult unboundResult(ReferenceLookupResult boundRes, ReferenceLookupResult unboundRes) { 3403 if (boundRes.isSuccess() && boundRes.sym.isStatic() && 3404 (!unboundRes.isSuccess() || unboundRes.hasKind(StaticKind.STATIC))) { 3405 //the first search produces a static method and no non-static method is applicable 3406 //during the second search 3407 return boundRes; 3408 } else if (unboundRes.isSuccess() && !unboundRes.sym.isStatic() && 3409 (!boundRes.isSuccess() || boundRes.hasKind(StaticKind.NON_STATIC))) { 3410 //the second search produces a non-static method and no static method is applicable 3411 //during the first search 3412 return unboundRes; 3413 } else if (boundRes.isSuccess() && unboundRes.isSuccess()) { 3414 //both searches produce some result; ambiguity (error recovery) 3415 return ReferenceLookupResult.error(ambiguityError(boundRes.sym, unboundRes.sym)); 3416 } else if (boundRes.isSuccess() || unboundRes.isSuccess()) { 3417 //Both searches failed to produce a result with correct staticness (i.e. first search 3418 //produces an non-static method). Alternatively, a given search produced a result 3419 //with the right staticness, but the other search has applicable methods with wrong 3420 //staticness (error recovery) 3421 return ReferenceLookupResult.error(new BadMethodReferenceError(boundRes.isSuccess() ? 3422 boundRes.sym : unboundRes.sym, true)); 3423 } else { 3424 //both searches fail to produce a result - pick 'better' error using heuristics (error recovery) 3425 return (boundRes.canIgnore() && !unboundRes.canIgnore()) ? 3426 unboundRes : boundRes; 3427 } 3428 } 3429 }; 3430 3431 /** 3432 * This chooser implements the selection strategy used during an arity-based lookup; this logic 3433 * is described in JLS SE 8 (15.12.2.1). 3434 */ 3435 ReferenceChooser structuralReferenceChooser = new ReferenceChooser() { 3436 3437 @Override 3438 ReferenceLookupResult boundResult(ReferenceLookupResult boundRes) { 3439 return (!boundRes.isSuccess() || !boundRes.hasKind(StaticKind.STATIC)) ? 3440 boundRes : //the search has at least one applicable non-static method 3441 ReferenceLookupResult.error(new BadMethodReferenceError(boundRes.sym, false)); 3442 } 3443 3444 @Override 3445 ReferenceLookupResult unboundResult(ReferenceLookupResult boundRes, ReferenceLookupResult unboundRes) { 3446 if (boundRes.isSuccess() && !boundRes.hasKind(StaticKind.NON_STATIC)) { 3447 //the first search has at least one applicable static method 3448 return boundRes; 3449 } else if (unboundRes.isSuccess() && !unboundRes.hasKind(StaticKind.STATIC)) { 3450 //the second search has at least one applicable non-static method 3451 return unboundRes; 3452 } else if (boundRes.isSuccess() || unboundRes.isSuccess()) { 3453 //either the first search produces a non-static method, or second search produces 3454 //a non-static method (error recovery) 3455 return ReferenceLookupResult.error(new BadMethodReferenceError(boundRes.isSuccess() ? 3456 boundRes.sym : unboundRes.sym, true)); 3457 } else { 3458 //both searches fail to produce a result - pick 'better' error using heuristics (error recovery) 3459 return (boundRes.canIgnore() && !unboundRes.canIgnore()) ? 3460 unboundRes : boundRes; 3461 } 3462 } 3463 }; 3464 3465 /** 3466 * Helper for defining custom method-like lookup logic; a lookup helper 3467 * provides hooks for (i) the actual lookup logic and (ii) accessing the 3468 * lookup result (this step might result in compiler diagnostics to be generated) 3469 */ 3470 abstract class LookupHelper { 3471 3472 /** name of the symbol to lookup */ 3473 Name name; 3474 3475 /** location in which the lookup takes place */ 3476 Type site; 3477 3478 /** actual types used during the lookup */ 3479 List<Type> argtypes; 3480 3481 /** type arguments used during the lookup */ 3482 List<Type> typeargtypes; 3483 3484 /** Max overload resolution phase handled by this helper */ 3485 MethodResolutionPhase maxPhase; 3486 3487 LookupHelper(Name name, Type site, List<Type> argtypes, List<Type> typeargtypes, MethodResolutionPhase maxPhase) { 3488 this.name = name; 3489 this.site = site; 3490 this.argtypes = argtypes; 3491 this.typeargtypes = typeargtypes; 3492 this.maxPhase = maxPhase; 3493 } 3494 3495 /** 3496 * Should lookup stop at given phase with given result 3497 */ 3498 final boolean shouldStop(Symbol sym, MethodResolutionPhase phase) { 3499 return phase.ordinal() > maxPhase.ordinal() || 3500 !sym.kind.isResolutionError() || sym.kind == AMBIGUOUS || sym.kind == STATICERR; 3501 } 3502 3503 /** 3504 * Search for a symbol under a given overload resolution phase - this method 3505 * is usually called several times, once per each overload resolution phase 3506 */ 3507 abstract Symbol lookup(Env<AttrContext> env, MethodResolutionPhase phase); 3508 3509 /** 3510 * Dump overload resolution info 3511 */ 3512 void debug(DiagnosticPosition pos, Symbol sym) { 3513 //do nothing 3514 } 3515 3516 /** 3517 * Validate the result of the lookup 3518 */ 3519 abstract Symbol access(Env<AttrContext> env, DiagnosticPosition pos, Symbol location, Symbol sym); 3520 } 3521 3522 abstract class BasicLookupHelper extends LookupHelper { 3523 3524 BasicLookupHelper(Name name, Type site, List<Type> argtypes, List<Type> typeargtypes) { 3525 this(name, site, argtypes, typeargtypes, MethodResolutionPhase.VARARITY); 3526 } 3527 3528 BasicLookupHelper(Name name, Type site, List<Type> argtypes, List<Type> typeargtypes, MethodResolutionPhase maxPhase) { 3529 super(name, site, argtypes, typeargtypes, maxPhase); 3530 } 3531 3532 @Override 3533 final Symbol lookup(Env<AttrContext> env, MethodResolutionPhase phase) { 3534 Symbol sym = doLookup(env, phase); 3535 if (sym.kind == AMBIGUOUS) { 3536 AmbiguityError a_err = (AmbiguityError)sym.baseSymbol(); 3537 sym = a_err.mergeAbstracts(site); 3538 } 3539 return sym; 3540 } 3541 3542 abstract Symbol doLookup(Env<AttrContext> env, MethodResolutionPhase phase); 3543 3544 @Override 3545 Symbol access(Env<AttrContext> env, DiagnosticPosition pos, Symbol location, Symbol sym) { 3546 if (sym.kind.isResolutionError()) { 3547 //if nothing is found return the 'first' error 3548 sym = accessMethod(sym, pos, location, site, name, true, argtypes, typeargtypes); 3549 } 3550 return sym; 3551 } 3552 3553 @Override 3554 void debug(DiagnosticPosition pos, Symbol sym) { 3555 reportVerboseResolutionDiagnostic(pos, name, site, argtypes, typeargtypes, sym); 3556 } 3557 } 3558 3559 /** 3560 * Helper class for member reference lookup. A reference lookup helper 3561 * defines the basic logic for member reference lookup; a method gives 3562 * access to an 'unbound' helper used to perform an unbound member 3563 * reference lookup. 3564 */ 3565 abstract class ReferenceLookupHelper extends LookupHelper { 3566 3567 /** The member reference tree */ 3568 JCMemberReference referenceTree; 3569 3570 ReferenceLookupHelper(JCMemberReference referenceTree, Name name, Type site, 3571 List<Type> argtypes, List<Type> typeargtypes, MethodResolutionPhase maxPhase) { 3572 super(name, site, argtypes, typeargtypes, maxPhase); 3573 this.referenceTree = referenceTree; 3574 } 3575 3576 /** 3577 * Returns an unbound version of this lookup helper. By default, this 3578 * method returns an dummy lookup helper. 3579 */ 3580 ReferenceLookupHelper unboundLookup(InferenceContext inferenceContext) { 3581 return null; 3582 } 3583 3584 /** 3585 * Get the kind of the member reference 3586 */ 3587 abstract JCMemberReference.ReferenceKind referenceKind(Symbol sym); 3588 3589 Symbol access(Env<AttrContext> env, DiagnosticPosition pos, Symbol location, Symbol sym) { 3590 if (sym.kind == AMBIGUOUS) { 3591 AmbiguityError a_err = (AmbiguityError)sym.baseSymbol(); 3592 sym = a_err.mergeAbstracts(site); 3593 } 3594 //skip error reporting 3595 return sym; 3596 } 3597 } 3598 3599 /** 3600 * Helper class for method reference lookup. The lookup logic is based 3601 * upon Resolve.findMethod; in certain cases, this helper class has a 3602 * corresponding unbound helper class (see UnboundMethodReferenceLookupHelper). 3603 * In such cases, non-static lookup results are thrown away. 3604 */ 3605 class MethodReferenceLookupHelper extends ReferenceLookupHelper { 3606 3607 /** The original method reference lookup site. */ 3608 Type originalSite; 3609 3610 MethodReferenceLookupHelper(JCMemberReference referenceTree, Name name, Type site, 3611 List<Type> argtypes, List<Type> typeargtypes, MethodResolutionPhase maxPhase) { 3612 super(referenceTree, name, types.skipTypeVars(site, true), argtypes, typeargtypes, maxPhase); 3613 this.originalSite = site; 3614 } 3615 3616 @Override 3617 final Symbol lookup(Env<AttrContext> env, MethodResolutionPhase phase) { 3618 return findMethod(env, site, name, argtypes, typeargtypes, 3619 phase.isBoxingRequired(), phase.isVarargsRequired()); 3620 } 3621 3622 @Override 3623 ReferenceLookupHelper unboundLookup(InferenceContext inferenceContext) { 3624 if (TreeInfo.isStaticSelector(referenceTree.expr, names)) { 3625 if (argtypes.nonEmpty() && 3626 (argtypes.head.hasTag(NONE) || 3627 types.isSubtypeUnchecked(inferenceContext.asUndetVar(argtypes.head.referenceProjectionOrSelf()), originalSite))) { 3628 return new UnboundMethodReferenceLookupHelper(referenceTree, name, 3629 originalSite, argtypes, typeargtypes, maxPhase); 3630 } else { 3631 return new ReferenceLookupHelper(referenceTree, name, site, argtypes, typeargtypes, maxPhase) { 3632 @Override 3633 ReferenceLookupHelper unboundLookup(InferenceContext inferenceContext) { 3634 return this; 3635 } 3636 3637 @Override 3638 Symbol lookup(Env<AttrContext> env, MethodResolutionPhase phase) { 3639 return methodNotFound; 3640 } 3641 3642 @Override 3643 ReferenceKind referenceKind(Symbol sym) { 3644 Assert.error(); 3645 return null; 3646 } 3647 }; 3648 } 3649 } else { 3650 return super.unboundLookup(inferenceContext); 3651 } 3652 } 3653 3654 @Override 3655 ReferenceKind referenceKind(Symbol sym) { 3656 if (sym.isStatic()) { 3657 return ReferenceKind.STATIC; 3658 } else { 3659 Name selName = TreeInfo.name(referenceTree.getQualifierExpression()); 3660 return selName != null && selName == names._super ? 3661 ReferenceKind.SUPER : 3662 ReferenceKind.BOUND; 3663 } 3664 } 3665 } 3666 3667 /** 3668 * Helper class for unbound method reference lookup. Essentially the same 3669 * as the basic method reference lookup helper; main difference is that static 3670 * lookup results are thrown away. If qualifier type is raw, an attempt to 3671 * infer a parameterized type is made using the first actual argument (that 3672 * would otherwise be ignored during the lookup). 3673 */ 3674 class UnboundMethodReferenceLookupHelper extends MethodReferenceLookupHelper { 3675 3676 UnboundMethodReferenceLookupHelper(JCMemberReference referenceTree, Name name, Type site, 3677 List<Type> argtypes, List<Type> typeargtypes, MethodResolutionPhase maxPhase) { 3678 super(referenceTree, name, site, argtypes.tail, typeargtypes, maxPhase); 3679 if (site.isRaw() && !argtypes.head.hasTag(NONE)) { 3680 Type asSuperSite = types.asSuper(argtypes.head.referenceProjectionOrSelf(), site.tsym); 3681 this.site = types.skipTypeVars(asSuperSite, true); 3682 } 3683 } 3684 3685 @Override 3686 ReferenceLookupHelper unboundLookup(InferenceContext inferenceContext) { 3687 return this; 3688 } 3689 3690 @Override 3691 ReferenceKind referenceKind(Symbol sym) { 3692 return ReferenceKind.UNBOUND; 3693 } 3694 } 3695 3696 /** 3697 * Helper class for array constructor lookup; an array constructor lookup 3698 * is simulated by looking up a method that returns the array type specified 3699 * as qualifier, and that accepts a single int parameter (size of the array). 3700 */ 3701 class ArrayConstructorReferenceLookupHelper extends ReferenceLookupHelper { 3702 3703 ArrayConstructorReferenceLookupHelper(JCMemberReference referenceTree, Type site, List<Type> argtypes, 3704 List<Type> typeargtypes, MethodResolutionPhase maxPhase) { 3705 // TODO - array constructor will be <init> 3706 super(referenceTree, site.tsym.isConcreteValueClass() ? names.vnew : names.init, site, argtypes, typeargtypes, maxPhase); 3707 } 3708 3709 @Override 3710 protected Symbol lookup(Env<AttrContext> env, MethodResolutionPhase phase) { 3711 WriteableScope sc = WriteableScope.create(syms.arrayClass); 3712 MethodSymbol arrayConstr = new MethodSymbol(PUBLIC, name, null, site.tsym); 3713 arrayConstr.type = new MethodType(List.of(syms.intType), site, List.nil(), syms.methodClass); 3714 sc.enter(arrayConstr); 3715 return findMethodInScope(env, site, name, argtypes, typeargtypes, sc, methodNotFound, phase.isBoxingRequired(), phase.isVarargsRequired(), false); 3716 } 3717 3718 @Override 3719 ReferenceKind referenceKind(Symbol sym) { 3720 return ReferenceKind.ARRAY_CTOR; 3721 } 3722 } 3723 3724 /** 3725 * Helper class for constructor reference lookup. The lookup logic is based 3726 * upon either Resolve.findMethod or Resolve.findDiamond - depending on 3727 * whether the constructor reference needs diamond inference (this is the case 3728 * if the qualifier type is raw). A special erroneous symbol is returned 3729 * if the lookup returns the constructor of an inner class and there's no 3730 * enclosing instance in scope. 3731 */ 3732 class ConstructorReferenceLookupHelper extends ReferenceLookupHelper { 3733 3734 boolean needsInference; 3735 3736 ConstructorReferenceLookupHelper(JCMemberReference referenceTree, Type site, List<Type> argtypes, 3737 List<Type> typeargtypes, MethodResolutionPhase maxPhase) { 3738 super(referenceTree, site.tsym.isConcreteValueClass() ? names.vnew : names.init, site, argtypes, typeargtypes, maxPhase); 3739 if (site.isRaw()) { 3740 this.site = new ClassType(site.getEnclosingType(), 3741 !(site.tsym.isInner() && site.getEnclosingType().isRaw()) ? 3742 site.tsym.type.getTypeArguments() : List.nil(), site.tsym, site.getMetadata(), site.getFlavor()); 3743 needsInference = true; 3744 } 3745 } 3746 3747 @Override 3748 protected Symbol lookup(Env<AttrContext> env, MethodResolutionPhase phase) { 3749 Symbol sym = needsInference ? 3750 findDiamond(env, site, argtypes, typeargtypes, phase.isBoxingRequired(), phase.isVarargsRequired()) : 3751 findMethod(env, site, name, argtypes, typeargtypes, 3752 phase.isBoxingRequired(), phase.isVarargsRequired()); 3753 return enclosingInstanceMissing(env, site) ? new BadConstructorReferenceError(sym) : sym; 3754 } 3755 3756 @Override 3757 ReferenceKind referenceKind(Symbol sym) { 3758 return site.getEnclosingType().hasTag(NONE) ? 3759 ReferenceKind.TOPLEVEL : ReferenceKind.IMPLICIT_INNER; 3760 } 3761 } 3762 3763 /** 3764 * Main overload resolution routine. On each overload resolution step, a 3765 * lookup helper class is used to perform the method/constructor lookup; 3766 * at the end of the lookup, the helper is used to validate the results 3767 * (this last step might trigger overload resolution diagnostics). 3768 */ 3769 Symbol lookupMethod(Env<AttrContext> env, DiagnosticPosition pos, Symbol location, MethodCheck methodCheck, LookupHelper lookupHelper) { 3770 MethodResolutionContext resolveContext = new MethodResolutionContext(); 3771 resolveContext.methodCheck = methodCheck; 3772 return lookupMethod(env, pos, location, resolveContext, lookupHelper); 3773 } 3774 3775 Symbol lookupMethod(Env<AttrContext> env, DiagnosticPosition pos, Symbol location, 3776 MethodResolutionContext resolveContext, LookupHelper lookupHelper) { 3777 MethodResolutionContext prevResolutionContext = currentResolutionContext; 3778 try { 3779 Symbol bestSoFar = methodNotFound; 3780 currentResolutionContext = resolveContext; 3781 for (MethodResolutionPhase phase : methodResolutionSteps) { 3782 if (lookupHelper.shouldStop(bestSoFar, phase)) 3783 break; 3784 MethodResolutionPhase prevPhase = currentResolutionContext.step; 3785 Symbol prevBest = bestSoFar; 3786 currentResolutionContext.step = phase; 3787 Symbol sym = lookupHelper.lookup(env, phase); 3788 lookupHelper.debug(pos, sym); 3789 bestSoFar = phase.mergeResults(bestSoFar, sym); 3790 env.info.pendingResolutionPhase = (prevBest == bestSoFar) ? prevPhase : phase; 3791 } 3792 return lookupHelper.access(env, pos, location, bestSoFar); 3793 } finally { 3794 currentResolutionContext = prevResolutionContext; 3795 } 3796 } 3797 3798 /** 3799 * Resolve `c.name' where name == this or name == super. 3800 * @param pos The position to use for error reporting. 3801 * @param env The environment current at the expression. 3802 * @param c The qualifier. 3803 * @param name The identifier's name. 3804 */ 3805 Symbol resolveSelf(DiagnosticPosition pos, 3806 Env<AttrContext> env, 3807 TypeSymbol c, 3808 Name name) { 3809 Env<AttrContext> env1 = env; 3810 boolean staticOnly = false; 3811 while (env1.outer != null) { 3812 if (isStatic(env1)) staticOnly = true; 3813 if (env1.enclClass.sym == c) { 3814 Symbol sym = env1.info.scope.findFirst(name); 3815 if (sym != null) { 3816 if (staticOnly) sym = new StaticError(sym); 3817 return accessBase(sym, pos, env.enclClass.sym.type, 3818 name, true); 3819 } 3820 } 3821 if ((env1.enclClass.sym.flags() & STATIC) != 0) staticOnly = true; 3822 env1 = env1.outer; 3823 } 3824 if (c.isInterface() && 3825 name == names._super && !isStatic(env) && 3826 types.isDirectSuperInterface(c, env.enclClass.sym)) { 3827 //this might be a default super call if one of the superinterfaces is 'c' 3828 for (Type t : pruneInterfaces(env.enclClass.type)) { 3829 if (t.tsym == c) { 3830 env.info.defaultSuperCallSite = t; 3831 return new VarSymbol(0, names._super, 3832 types.asSuper(env.enclClass.type.referenceProjectionOrSelf(), c), env.enclClass.sym); 3833 } 3834 } 3835 //find a direct supertype that is a subtype of 'c' 3836 for (Type i : types.directSupertypes(env.enclClass.type)) { 3837 if (i.tsym.isSubClass(c, types) && i.tsym != c) { 3838 log.error(pos, 3839 Errors.IllegalDefaultSuperCall(c, 3840 Fragments.RedundantSupertype(c, i))); 3841 return syms.errSymbol; 3842 } 3843 } 3844 Assert.error(); 3845 } 3846 log.error(pos, Errors.NotEnclClass(c)); 3847 return syms.errSymbol; 3848 } 3849 //where 3850 private List<Type> pruneInterfaces(Type t) { 3851 ListBuffer<Type> result = new ListBuffer<>(); 3852 for (Type t1 : types.interfaces(t)) { 3853 boolean shouldAdd = true; 3854 for (Type t2 : types.directSupertypes(t)) { 3855 if (t1 != t2 && !t2.hasTag(ERROR) && types.isSubtypeNoCapture(t2, t1)) { 3856 shouldAdd = false; 3857 } 3858 } 3859 if (shouldAdd) { 3860 result.append(t1); 3861 } 3862 } 3863 return result.toList(); 3864 } 3865 3866 3867 /** 3868 * Resolve `c.this' for an enclosing class c that contains the 3869 * named member. 3870 * @param pos The position to use for error reporting. 3871 * @param env The environment current at the expression. 3872 * @param member The member that must be contained in the result. 3873 */ 3874 Symbol resolveSelfContaining(DiagnosticPosition pos, 3875 Env<AttrContext> env, 3876 Symbol member, 3877 boolean isSuperCall) { 3878 Symbol sym = resolveSelfContainingInternal(env, member, isSuperCall); 3879 if (sym == null) { 3880 log.error(pos, Errors.EnclClassRequired(member)); 3881 return syms.errSymbol; 3882 } else { 3883 return accessBase(sym, pos, env.enclClass.sym.type, sym.name, true); 3884 } 3885 } 3886 3887 boolean enclosingInstanceMissing(Env<AttrContext> env, Type type) { 3888 if (type.hasTag(CLASS) && type.getEnclosingType().hasTag(CLASS)) { 3889 Symbol encl = resolveSelfContainingInternal(env, type.tsym, false); 3890 return encl == null || encl.kind.isResolutionError(); 3891 } 3892 return false; 3893 } 3894 3895 private Symbol resolveSelfContainingInternal(Env<AttrContext> env, 3896 Symbol member, 3897 boolean isSuperCall) { 3898 Name name = names._this; 3899 Env<AttrContext> env1 = isSuperCall ? env.outer : env; 3900 boolean staticOnly = false; 3901 if (env1 != null) { 3902 while (env1 != null && env1.outer != null) { 3903 if (isStatic(env1)) staticOnly = true; 3904 if (env1.enclClass.sym.isSubClass(member.owner.enclClass(), types)) { 3905 Symbol sym = env1.info.scope.findFirst(name); 3906 if (sym != null) { 3907 if (staticOnly) sym = new StaticError(sym); 3908 return sym; 3909 } 3910 } 3911 if ((env1.enclClass.sym.flags() & STATIC) != 0) 3912 staticOnly = true; 3913 env1 = env1.outer; 3914 } 3915 } 3916 return null; 3917 } 3918 3919 /** 3920 * Resolve an appropriate implicit this instance for t's container. 3921 * JLS 8.8.5.1 and 15.9.2 3922 */ 3923 Type resolveImplicitThis(DiagnosticPosition pos, Env<AttrContext> env, Type t) { 3924 return resolveImplicitThis(pos, env, t, false); 3925 } 3926 3927 Type resolveImplicitThis(DiagnosticPosition pos, Env<AttrContext> env, Type t, boolean isSuperCall) { 3928 Type thisType = (t.tsym.owner.kind.matches(KindSelector.VAL_MTH) 3929 ? resolveSelf(pos, env, t.getEnclosingType().tsym, names._this) 3930 : resolveSelfContaining(pos, env, t.tsym, isSuperCall)).type; 3931 if (env.info.isSelfCall && thisType.tsym == env.enclClass.sym) { 3932 log.error(pos, Errors.CantRefBeforeCtorCalled("this")); 3933 } 3934 return thisType; 3935 } 3936 3937 /* *************************************************************************** 3938 * ResolveError classes, indicating error situations when accessing symbols 3939 ****************************************************************************/ 3940 3941 //used by TransTypes when checking target type of synthetic cast 3942 public void logAccessErrorInternal(Env<AttrContext> env, JCTree tree, Type type) { 3943 AccessError error = new AccessError(env, env.enclClass.type, type.tsym); 3944 logResolveError(error, tree.pos(), env.enclClass.sym, env.enclClass.type, null, null, null); 3945 } 3946 //where 3947 private void logResolveError(ResolveError error, 3948 DiagnosticPosition pos, 3949 Symbol location, 3950 Type site, 3951 Name name, 3952 List<Type> argtypes, 3953 List<Type> typeargtypes) { 3954 JCDiagnostic d = error.getDiagnostic(JCDiagnostic.DiagnosticType.ERROR, 3955 pos, location, site, name, argtypes, typeargtypes); 3956 if (d != null) { 3957 d.setFlag(DiagnosticFlag.RESOLVE_ERROR); 3958 log.report(d); 3959 } 3960 } 3961 3962 private final LocalizedString noArgs = new LocalizedString("compiler.misc.no.args"); 3963 3964 public Object methodArguments(List<Type> argtypes) { 3965 if (argtypes == null || argtypes.isEmpty()) { 3966 return noArgs; 3967 } else { 3968 ListBuffer<Object> diagArgs = new ListBuffer<>(); 3969 for (Type t : argtypes) { 3970 if (t.hasTag(DEFERRED)) { 3971 diagArgs.append(((DeferredAttr.DeferredType)t).tree); 3972 } else { 3973 diagArgs.append(t); 3974 } 3975 } 3976 return diagArgs; 3977 } 3978 } 3979 3980 /** check if a type is a subtype of Serializable, if that is available.*/ 3981 boolean isSerializable(Type t) { 3982 try { 3983 syms.serializableType.complete(); 3984 } 3985 catch (CompletionFailure e) { 3986 return false; 3987 } 3988 return types.isSubtype(t, syms.serializableType); 3989 } 3990 3991 /** 3992 * Root class for resolution errors. Subclass of ResolveError 3993 * represent a different kinds of resolution error - as such they must 3994 * specify how they map into concrete compiler diagnostics. 3995 */ 3996 abstract class ResolveError extends Symbol { 3997 3998 /** The name of the kind of error, for debugging only. */ 3999 final String debugName; 4000 4001 ResolveError(Kind kind, String debugName) { 4002 super(kind, 0, null, null, null); 4003 this.debugName = debugName; 4004 } 4005 4006 @Override @DefinedBy(Api.LANGUAGE_MODEL) 4007 public <R, P> R accept(ElementVisitor<R, P> v, P p) { 4008 throw new AssertionError(); 4009 } 4010 4011 @Override 4012 public String toString() { 4013 return debugName; 4014 } 4015 4016 @Override 4017 public boolean exists() { 4018 return false; 4019 } 4020 4021 @Override 4022 public boolean isStatic() { 4023 return false; 4024 } 4025 4026 /** 4027 * Create an external representation for this erroneous symbol to be 4028 * used during attribution - by default this returns the symbol of a 4029 * brand new error type which stores the original type found 4030 * during resolution. 4031 * 4032 * @param name the name used during resolution 4033 * @param location the location from which the symbol is accessed 4034 */ 4035 protected Symbol access(Name name, TypeSymbol location) { 4036 return types.createErrorType(name, location, syms.errSymbol.type).tsym; 4037 } 4038 4039 /** 4040 * Create a diagnostic representing this resolution error. 4041 * 4042 * @param dkind The kind of the diagnostic to be created (e.g error). 4043 * @param pos The position to be used for error reporting. 4044 * @param site The original type from where the selection took place. 4045 * @param name The name of the symbol to be resolved. 4046 * @param argtypes The invocation's value arguments, 4047 * if we looked for a method. 4048 * @param typeargtypes The invocation's type arguments, 4049 * if we looked for a method. 4050 */ 4051 abstract JCDiagnostic getDiagnostic(JCDiagnostic.DiagnosticType dkind, 4052 DiagnosticPosition pos, 4053 Symbol location, 4054 Type site, 4055 Name name, 4056 List<Type> argtypes, 4057 List<Type> typeargtypes); 4058 } 4059 4060 /** 4061 * This class is the root class of all resolution errors caused by 4062 * an invalid symbol being found during resolution. 4063 */ 4064 abstract class InvalidSymbolError extends ResolveError { 4065 4066 /** The invalid symbol found during resolution */ 4067 Symbol sym; 4068 4069 InvalidSymbolError(Kind kind, Symbol sym, String debugName) { 4070 super(kind, debugName); 4071 this.sym = sym; 4072 } 4073 4074 @Override 4075 public boolean exists() { 4076 return true; 4077 } 4078 4079 @Override 4080 public String toString() { 4081 return super.toString() + " wrongSym=" + sym; 4082 } 4083 4084 @Override 4085 public Symbol access(Name name, TypeSymbol location) { 4086 if (!sym.kind.isResolutionError() && sym.kind.matches(KindSelector.TYP)) 4087 return types.createErrorType(name, location, sym.type).tsym; 4088 else 4089 return sym; 4090 } 4091 } 4092 4093 class BadRestrictedTypeError extends ResolveError { 4094 private final Name typeName; 4095 BadRestrictedTypeError(Name typeName) { 4096 super(Kind.BAD_RESTRICTED_TYPE, "bad var use"); 4097 this.typeName = typeName; 4098 } 4099 4100 @Override 4101 JCDiagnostic getDiagnostic(DiagnosticType dkind, DiagnosticPosition pos, Symbol location, Type site, Name name, List<Type> argtypes, List<Type> typeargtypes) { 4102 return diags.create(dkind, log.currentSource(), pos, "illegal.ref.to.restricted.type", typeName); 4103 } 4104 } 4105 4106 /** 4107 * InvalidSymbolError error class indicating that a symbol matching a 4108 * given name does not exists in a given site. 4109 */ 4110 class SymbolNotFoundError extends ResolveError { 4111 4112 SymbolNotFoundError(Kind kind) { 4113 this(kind, "symbol not found error"); 4114 } 4115 4116 SymbolNotFoundError(Kind kind, String debugName) { 4117 super(kind, debugName); 4118 } 4119 4120 @Override 4121 JCDiagnostic getDiagnostic(JCDiagnostic.DiagnosticType dkind, 4122 DiagnosticPosition pos, 4123 Symbol location, 4124 Type site, 4125 Name name, 4126 List<Type> argtypes, 4127 List<Type> typeargtypes) { 4128 argtypes = argtypes == null ? List.nil() : argtypes; 4129 typeargtypes = typeargtypes == null ? List.nil() : typeargtypes; 4130 if (name == names.error) 4131 return null; 4132 4133 boolean hasLocation = false; 4134 if (location == null) { 4135 location = site.tsym; 4136 } 4137 if (!location.name.isEmpty()) { 4138 if (location.kind == PCK && !site.tsym.exists() && location.name != names.java) { 4139 return diags.create(dkind, log.currentSource(), pos, 4140 "doesnt.exist", location); 4141 } 4142 hasLocation = !location.name.equals(names._this) && 4143 !location.name.equals(names._super); 4144 } 4145 boolean isConstructor = names.isInitOrVNew(name); 4146 KindName kindname = isConstructor ? KindName.CONSTRUCTOR : kind.absentKind(); 4147 Name idname = isConstructor ? site.tsym.name : name; 4148 String errKey = getErrorKey(kindname, typeargtypes.nonEmpty(), hasLocation); 4149 if (hasLocation) { 4150 return diags.create(dkind, log.currentSource(), pos, 4151 errKey, kindname, idname, //symbol kindname, name 4152 typeargtypes, args(argtypes), //type parameters and arguments (if any) 4153 getLocationDiag(location, site)); //location kindname, type 4154 } 4155 else { 4156 return diags.create(dkind, log.currentSource(), pos, 4157 errKey, kindname, idname, //symbol kindname, name 4158 typeargtypes, args(argtypes)); //type parameters and arguments (if any) 4159 } 4160 } 4161 //where 4162 private Object args(List<Type> args) { 4163 return args.isEmpty() ? args : methodArguments(args); 4164 } 4165 4166 private String getErrorKey(KindName kindname, boolean hasTypeArgs, boolean hasLocation) { 4167 String key = "cant.resolve"; 4168 String suffix = hasLocation ? ".location" : ""; 4169 switch (kindname) { 4170 case METHOD: 4171 case CONSTRUCTOR: { 4172 suffix += ".args"; 4173 suffix += hasTypeArgs ? ".params" : ""; 4174 } 4175 } 4176 return key + suffix; 4177 } 4178 private JCDiagnostic getLocationDiag(Symbol location, Type site) { 4179 if (location.kind == VAR) { 4180 return diags.fragment(Fragments.Location1(kindName(location), 4181 location, 4182 location.type)); 4183 } else { 4184 return diags.fragment(Fragments.Location(typeKindName(site), 4185 site, 4186 null)); 4187 } 4188 } 4189 } 4190 4191 /** 4192 * InvalidSymbolError error class indicating that a given symbol 4193 * (either a method, a constructor or an operand) is not applicable 4194 * given an actual arguments/type argument list. 4195 */ 4196 class InapplicableSymbolError extends ResolveError { 4197 4198 protected MethodResolutionContext resolveContext; 4199 4200 InapplicableSymbolError(MethodResolutionContext context) { 4201 this(WRONG_MTH, "inapplicable symbol error", context); 4202 } 4203 4204 protected InapplicableSymbolError(Kind kind, String debugName, MethodResolutionContext context) { 4205 super(kind, debugName); 4206 this.resolveContext = context; 4207 } 4208 4209 @Override 4210 public String toString() { 4211 return super.toString(); 4212 } 4213 4214 @Override 4215 public boolean exists() { 4216 return true; 4217 } 4218 4219 @Override 4220 JCDiagnostic getDiagnostic(JCDiagnostic.DiagnosticType dkind, 4221 DiagnosticPosition pos, 4222 Symbol location, 4223 Type site, 4224 Name name, 4225 List<Type> argtypes, 4226 List<Type> typeargtypes) { 4227 if (name == names.error) 4228 return null; 4229 4230 Pair<Symbol, JCDiagnostic> c = errCandidate(); 4231 Symbol ws = c.fst.asMemberOf(site, types); 4232 4233 // If the problem is due to type arguments, then the method parameters aren't relevant, 4234 // so use the error message that omits them to avoid confusion. 4235 switch (c.snd.getCode()) { 4236 case "compiler.misc.wrong.number.type.args": 4237 case "compiler.misc.explicit.param.do.not.conform.to.bounds": 4238 return diags.create(dkind, log.currentSource(), pos, 4239 "cant.apply.symbol.noargs", 4240 compactMethodDiags ? 4241 d -> MethodResolutionDiagHelper.rewrite(diags, pos, log.currentSource(), dkind, c.snd) : null, 4242 kindName(ws), 4243 names.isInitOrVNew(ws.name) ? ws.owner.name : ws.name, 4244 ws.owner.type, 4245 c.snd); 4246 default: 4247 return diags.create(dkind, log.currentSource(), pos, 4248 "cant.apply.symbol", 4249 compactMethodDiags ? 4250 d -> MethodResolutionDiagHelper.rewrite(diags, pos, log.currentSource(), dkind, c.snd) : null, 4251 kindName(ws), 4252 names.isInitOrVNew(ws.name) ? ws.owner.name : ws.name, 4253 methodArguments(ws.type.getParameterTypes()), 4254 methodArguments(argtypes), 4255 kindName(ws.owner), 4256 ws.owner.type, 4257 c.snd); 4258 } 4259 } 4260 4261 @Override 4262 public Symbol access(Name name, TypeSymbol location) { 4263 Pair<Symbol, JCDiagnostic> cand = errCandidate(); 4264 TypeSymbol errSymbol = types.createErrorType(name, location, cand != null ? cand.fst.type : syms.errSymbol.type).tsym; 4265 if (cand != null) { 4266 attrRecover.wrongMethodSymbolCandidate(errSymbol, cand.fst, cand.snd); 4267 } 4268 return errSymbol; 4269 } 4270 4271 protected Pair<Symbol, JCDiagnostic> errCandidate() { 4272 Candidate bestSoFar = null; 4273 for (Candidate c : resolveContext.candidates) { 4274 if (c.isApplicable()) continue; 4275 bestSoFar = c; 4276 } 4277 Assert.checkNonNull(bestSoFar); 4278 return new Pair<>(bestSoFar.sym, bestSoFar.details); 4279 } 4280 } 4281 4282 /** 4283 * ResolveError error class indicating that a symbol (either methods, constructors or operand) 4284 * is not applicable given an actual arguments/type argument list. 4285 */ 4286 class InapplicableSymbolsError extends InapplicableSymbolError { 4287 4288 InapplicableSymbolsError(MethodResolutionContext context) { 4289 super(WRONG_MTHS, "inapplicable symbols", context); 4290 } 4291 4292 @Override 4293 JCDiagnostic getDiagnostic(JCDiagnostic.DiagnosticType dkind, 4294 DiagnosticPosition pos, 4295 Symbol location, 4296 Type site, 4297 Name name, 4298 List<Type> argtypes, 4299 List<Type> typeargtypes) { 4300 Map<Symbol, JCDiagnostic> candidatesMap = mapCandidates(); 4301 Map<Symbol, JCDiagnostic> filteredCandidates = compactMethodDiags ? 4302 filterCandidates(candidatesMap) : 4303 mapCandidates(); 4304 if (filteredCandidates.isEmpty()) { 4305 filteredCandidates = candidatesMap; 4306 } 4307 boolean truncatedDiag = candidatesMap.size() != filteredCandidates.size(); 4308 if (filteredCandidates.size() > 1) { 4309 boolean isConstructor = names.isInitOrVNew(name); 4310 JCDiagnostic err = diags.create(dkind, 4311 null, 4312 truncatedDiag ? 4313 EnumSet.of(DiagnosticFlag.COMPRESSED) : 4314 EnumSet.noneOf(DiagnosticFlag.class), 4315 log.currentSource(), 4316 pos, 4317 "cant.apply.symbols", 4318 isConstructor ? KindName.CONSTRUCTOR : kind.absentKind(), 4319 isConstructor ? site.tsym.name : name, 4320 methodArguments(argtypes)); 4321 return new JCDiagnostic.MultilineDiagnostic(err, candidateDetails(filteredCandidates, site)); 4322 } else if (filteredCandidates.size() == 1) { 4323 Map.Entry<Symbol, JCDiagnostic> _e = 4324 filteredCandidates.entrySet().iterator().next(); 4325 final Pair<Symbol, JCDiagnostic> p = new Pair<>(_e.getKey(), _e.getValue()); 4326 JCDiagnostic d = new InapplicableSymbolError(resolveContext) { 4327 @Override 4328 protected Pair<Symbol, JCDiagnostic> errCandidate() { 4329 return p; 4330 } 4331 }.getDiagnostic(dkind, pos, 4332 location, site, name, argtypes, typeargtypes); 4333 if (truncatedDiag) { 4334 d.setFlag(DiagnosticFlag.COMPRESSED); 4335 } 4336 return d; 4337 } else { 4338 return new SymbolNotFoundError(ABSENT_MTH).getDiagnostic(dkind, pos, 4339 location, site, name, argtypes, typeargtypes); 4340 } 4341 } 4342 //where 4343 private Map<Symbol, JCDiagnostic> mapCandidates() { 4344 MostSpecificMap candidates = new MostSpecificMap(); 4345 for (Candidate c : resolveContext.candidates) { 4346 if (c.isApplicable()) continue; 4347 candidates.put(c); 4348 } 4349 return candidates; 4350 } 4351 4352 @SuppressWarnings("serial") 4353 private class MostSpecificMap extends LinkedHashMap<Symbol, JCDiagnostic> { 4354 private void put(Candidate c) { 4355 ListBuffer<Symbol> overridden = new ListBuffer<>(); 4356 for (Symbol s : keySet()) { 4357 if (s == c.sym) { 4358 continue; 4359 } 4360 if (c.sym.overrides(s, (TypeSymbol)s.owner, types, false)) { 4361 overridden.add(s); 4362 } else if (s.overrides(c.sym, (TypeSymbol)c.sym.owner, types, false)) { 4363 return; 4364 } 4365 } 4366 for (Symbol s : overridden) { 4367 remove(s); 4368 } 4369 put(c.sym, c.details); 4370 } 4371 } 4372 4373 Map<Symbol, JCDiagnostic> filterCandidates(Map<Symbol, JCDiagnostic> candidatesMap) { 4374 Map<Symbol, JCDiagnostic> candidates = new LinkedHashMap<>(); 4375 for (Map.Entry<Symbol, JCDiagnostic> _entry : candidatesMap.entrySet()) { 4376 JCDiagnostic d = _entry.getValue(); 4377 if (!new Template(MethodCheckDiag.ARITY_MISMATCH.regex()).matches(d)) { 4378 candidates.put(_entry.getKey(), d); 4379 } 4380 } 4381 return candidates; 4382 } 4383 4384 private List<JCDiagnostic> candidateDetails(Map<Symbol, JCDiagnostic> candidatesMap, Type site) { 4385 List<JCDiagnostic> details = List.nil(); 4386 for (Map.Entry<Symbol, JCDiagnostic> _entry : candidatesMap.entrySet()) { 4387 Symbol sym = _entry.getKey(); 4388 JCDiagnostic detailDiag = 4389 diags.fragment(Fragments.InapplicableMethod(Kinds.kindName(sym), 4390 sym.location(site, types), 4391 sym.asMemberOf(site, types), 4392 _entry.getValue())); 4393 details = details.prepend(detailDiag); 4394 } 4395 //typically members are visited in reverse order (see Scope) 4396 //so we need to reverse the candidate list so that candidates 4397 //conform to source order 4398 return details; 4399 } 4400 4401 @Override 4402 protected Pair<Symbol, JCDiagnostic> errCandidate() { 4403 Map<Symbol, JCDiagnostic> candidatesMap = mapCandidates(); 4404 Map<Symbol, JCDiagnostic> filteredCandidates = filterCandidates(candidatesMap); 4405 if (filteredCandidates.size() == 1) { 4406 return Pair.of(filteredCandidates.keySet().iterator().next(), 4407 filteredCandidates.values().iterator().next()); 4408 } 4409 return null; 4410 } 4411 } 4412 4413 /** 4414 * DiamondError error class indicating that a constructor symbol is not applicable 4415 * given an actual arguments/type argument list using diamond inference. 4416 */ 4417 class DiamondError extends InapplicableSymbolError { 4418 4419 Symbol sym; 4420 4421 public DiamondError(Symbol sym, MethodResolutionContext context) { 4422 super(sym.kind, "diamondError", context); 4423 this.sym = sym; 4424 } 4425 4426 JCDiagnostic getDetails() { 4427 return (sym.kind == WRONG_MTH) ? 4428 ((InapplicableSymbolError)sym.baseSymbol()).errCandidate().snd : 4429 null; 4430 } 4431 4432 @Override 4433 JCDiagnostic getDiagnostic(DiagnosticType dkind, DiagnosticPosition pos, 4434 Symbol location, Type site, Name name, List<Type> argtypes, List<Type> typeargtypes) { 4435 JCDiagnostic details = getDetails(); 4436 if (details != null && compactMethodDiags) { 4437 JCDiagnostic simpleDiag = 4438 MethodResolutionDiagHelper.rewrite(diags, pos, log.currentSource(), dkind, details); 4439 if (simpleDiag != null) { 4440 return simpleDiag; 4441 } 4442 } 4443 String key = details == null ? 4444 "cant.apply.diamond" : 4445 "cant.apply.diamond.1"; 4446 return diags.create(dkind, log.currentSource(), pos, key, 4447 Fragments.Diamond(site.tsym), details); 4448 } 4449 } 4450 4451 /** 4452 * An InvalidSymbolError error class indicating that a symbol is not 4453 * accessible from a given site 4454 */ 4455 class AccessError extends InvalidSymbolError { 4456 4457 private Env<AttrContext> env; 4458 private Type site; 4459 4460 AccessError(Env<AttrContext> env, Type site, Symbol sym) { 4461 super(HIDDEN, sym, "access error"); 4462 this.env = env; 4463 this.site = site; 4464 } 4465 4466 @Override 4467 public boolean exists() { 4468 return false; 4469 } 4470 4471 @Override 4472 JCDiagnostic getDiagnostic(JCDiagnostic.DiagnosticType dkind, 4473 DiagnosticPosition pos, 4474 Symbol location, 4475 Type site, 4476 Name name, 4477 List<Type> argtypes, 4478 List<Type> typeargtypes) { 4479 if (names.isInitOrVNew(sym.name) && sym.owner != site.tsym) { 4480 return new SymbolNotFoundError(ABSENT_MTH).getDiagnostic(dkind, 4481 pos, location, site, name, argtypes, typeargtypes); 4482 } 4483 else if ((sym.flags() & PUBLIC) != 0 4484 || (env != null && this.site != null 4485 && !isAccessible(env, this.site))) { 4486 if (sym.owner.kind == PCK) { 4487 return diags.create(dkind, log.currentSource(), 4488 pos, "not.def.access.package.cant.access", 4489 sym, sym.location(), inaccessiblePackageReason(env, sym.packge())); 4490 } else if ( sym.packge() != syms.rootPackage 4491 && !symbolPackageVisible(env, sym)) { 4492 return diags.create(dkind, log.currentSource(), 4493 pos, "not.def.access.class.intf.cant.access.reason", 4494 sym, sym.location(), sym.location().packge(), 4495 inaccessiblePackageReason(env, sym.packge())); 4496 } else { 4497 return diags.create(dkind, log.currentSource(), 4498 pos, "not.def.access.class.intf.cant.access", 4499 sym, sym.location()); 4500 } 4501 } 4502 else if ((sym.flags() & (PRIVATE | PROTECTED)) != 0) { 4503 return diags.create(dkind, log.currentSource(), 4504 pos, "report.access", sym, 4505 asFlagSet(sym.flags() & (PRIVATE | PROTECTED)), 4506 sym.location()); 4507 } 4508 else { 4509 return diags.create(dkind, log.currentSource(), 4510 pos, "not.def.public.cant.access", sym, sym.location()); 4511 } 4512 } 4513 4514 private String toString(Type type) { 4515 StringBuilder sb = new StringBuilder(); 4516 sb.append(type); 4517 if (type != null) { 4518 sb.append("[tsym:").append(type.tsym); 4519 if (type.tsym != null) 4520 sb.append("packge:").append(type.tsym.packge()); 4521 sb.append("]"); 4522 } 4523 return sb.toString(); 4524 } 4525 } 4526 4527 class InvisibleSymbolError extends InvalidSymbolError { 4528 4529 private final Env<AttrContext> env; 4530 private final boolean suppressError; 4531 4532 InvisibleSymbolError(Env<AttrContext> env, boolean suppressError, Symbol sym) { 4533 super(HIDDEN, sym, "invisible class error"); 4534 this.env = env; 4535 this.suppressError = suppressError; 4536 this.name = sym.name; 4537 } 4538 4539 @Override 4540 JCDiagnostic getDiagnostic(JCDiagnostic.DiagnosticType dkind, 4541 DiagnosticPosition pos, 4542 Symbol location, 4543 Type site, 4544 Name name, 4545 List<Type> argtypes, 4546 List<Type> typeargtypes) { 4547 if (suppressError) 4548 return null; 4549 4550 if (sym.kind == PCK) { 4551 JCDiagnostic details = inaccessiblePackageReason(env, sym.packge()); 4552 return diags.create(dkind, log.currentSource(), 4553 pos, "package.not.visible", sym, details); 4554 } 4555 4556 JCDiagnostic details = inaccessiblePackageReason(env, sym.packge()); 4557 4558 if (pos.getTree() != null) { 4559 Symbol o = sym; 4560 JCTree tree = pos.getTree(); 4561 4562 while (o.kind != PCK && tree.hasTag(SELECT)) { 4563 o = o.owner; 4564 tree = ((JCFieldAccess) tree).selected; 4565 } 4566 4567 if (o.kind == PCK) { 4568 pos = tree.pos(); 4569 4570 return diags.create(dkind, log.currentSource(), 4571 pos, "package.not.visible", o, details); 4572 } 4573 } 4574 4575 return diags.create(dkind, log.currentSource(), 4576 pos, "not.def.access.package.cant.access", sym, sym.packge(), details); 4577 } 4578 } 4579 4580 JCDiagnostic inaccessiblePackageReason(Env<AttrContext> env, PackageSymbol sym) { 4581 //no dependency: 4582 if (!env.toplevel.modle.readModules.contains(sym.modle)) { 4583 //does not read: 4584 if (sym.modle != syms.unnamedModule) { 4585 if (env.toplevel.modle != syms.unnamedModule) { 4586 return diags.fragment(Fragments.NotDefAccessDoesNotRead(env.toplevel.modle, 4587 sym, 4588 sym.modle)); 4589 } else { 4590 return diags.fragment(Fragments.NotDefAccessDoesNotReadFromUnnamed(sym, 4591 sym.modle)); 4592 } 4593 } else { 4594 return diags.fragment(Fragments.NotDefAccessDoesNotReadUnnamed(sym, 4595 env.toplevel.modle)); 4596 } 4597 } else { 4598 if (sym.packge().modle.exports.stream().anyMatch(e -> e.packge == sym)) { 4599 //not exported to this module: 4600 if (env.toplevel.modle != syms.unnamedModule) { 4601 return diags.fragment(Fragments.NotDefAccessNotExportedToModule(sym, 4602 sym.modle, 4603 env.toplevel.modle)); 4604 } else { 4605 return diags.fragment(Fragments.NotDefAccessNotExportedToModuleFromUnnamed(sym, 4606 sym.modle)); 4607 } 4608 } else { 4609 //not exported: 4610 if (env.toplevel.modle != syms.unnamedModule) { 4611 return diags.fragment(Fragments.NotDefAccessNotExported(sym, 4612 sym.modle)); 4613 } else { 4614 return diags.fragment(Fragments.NotDefAccessNotExportedFromUnnamed(sym, 4615 sym.modle)); 4616 } 4617 } 4618 } 4619 } 4620 4621 /** 4622 * InvalidSymbolError error class indicating that an instance member 4623 * has erroneously been accessed from a static context. 4624 */ 4625 class StaticError extends InvalidSymbolError { 4626 4627 StaticError(Symbol sym) { 4628 super(STATICERR, sym, "static error"); 4629 } 4630 4631 @Override 4632 JCDiagnostic getDiagnostic(JCDiagnostic.DiagnosticType dkind, 4633 DiagnosticPosition pos, 4634 Symbol location, 4635 Type site, 4636 Name name, 4637 List<Type> argtypes, 4638 List<Type> typeargtypes) { 4639 Symbol errSym = ((sym.kind == TYP && sym.type.hasTag(CLASS)) 4640 ? types.erasure(sym.type).tsym 4641 : sym); 4642 return diags.create(dkind, log.currentSource(), pos, 4643 "non-static.cant.be.ref", kindName(sym), errSym); 4644 } 4645 } 4646 4647 /** 4648 * InvalidSymbolError error class indicating that a pair of symbols 4649 * (either methods, constructors or operands) are ambiguous 4650 * given an actual arguments/type argument list. 4651 */ 4652 class AmbiguityError extends ResolveError { 4653 4654 /** The other maximally specific symbol */ 4655 List<Symbol> ambiguousSyms = List.nil(); 4656 4657 @Override 4658 public boolean exists() { 4659 return true; 4660 } 4661 4662 AmbiguityError(Symbol sym1, Symbol sym2) { 4663 super(AMBIGUOUS, "ambiguity error"); 4664 ambiguousSyms = flatten(sym2).appendList(flatten(sym1)); 4665 } 4666 4667 private List<Symbol> flatten(Symbol sym) { 4668 if (sym.kind == AMBIGUOUS) { 4669 return ((AmbiguityError)sym.baseSymbol()).ambiguousSyms; 4670 } else { 4671 return List.of(sym); 4672 } 4673 } 4674 4675 AmbiguityError addAmbiguousSymbol(Symbol s) { 4676 ambiguousSyms = ambiguousSyms.prepend(s); 4677 return this; 4678 } 4679 4680 @Override 4681 JCDiagnostic getDiagnostic(JCDiagnostic.DiagnosticType dkind, 4682 DiagnosticPosition pos, 4683 Symbol location, 4684 Type site, 4685 Name name, 4686 List<Type> argtypes, 4687 List<Type> typeargtypes) { 4688 List<Symbol> diagSyms = ambiguousSyms.reverse(); 4689 Symbol s1 = diagSyms.head; 4690 Symbol s2 = diagSyms.tail.head; 4691 Name sname = s1.name; 4692 if (names.isInitOrVNew(sname)) sname = s1.owner.name; 4693 return diags.create(dkind, log.currentSource(), 4694 pos, "ref.ambiguous", sname, 4695 kindName(s1), 4696 s1, 4697 s1.location(site, types), 4698 kindName(s2), 4699 s2, 4700 s2.location(site, types)); 4701 } 4702 4703 /** 4704 * If multiple applicable methods are found during overload and none of them 4705 * is more specific than the others, attempt to merge their signatures. 4706 */ 4707 Symbol mergeAbstracts(Type site) { 4708 List<Symbol> ambiguousInOrder = ambiguousSyms.reverse(); 4709 return types.mergeAbstracts(ambiguousInOrder, site, true).orElse(this); 4710 } 4711 4712 @Override 4713 protected Symbol access(Name name, TypeSymbol location) { 4714 Symbol firstAmbiguity = ambiguousSyms.last(); 4715 return firstAmbiguity.kind == TYP ? 4716 types.createErrorType(name, location, firstAmbiguity.type).tsym : 4717 firstAmbiguity; 4718 } 4719 } 4720 4721 class BadVarargsMethod extends ResolveError { 4722 4723 ResolveError delegatedError; 4724 4725 BadVarargsMethod(ResolveError delegatedError) { 4726 super(delegatedError.kind, "badVarargs"); 4727 this.delegatedError = delegatedError; 4728 } 4729 4730 @Override 4731 public Symbol baseSymbol() { 4732 return delegatedError.baseSymbol(); 4733 } 4734 4735 @Override 4736 protected Symbol access(Name name, TypeSymbol location) { 4737 return delegatedError.access(name, location); 4738 } 4739 4740 @Override 4741 public boolean exists() { 4742 return true; 4743 } 4744 4745 @Override 4746 JCDiagnostic getDiagnostic(DiagnosticType dkind, DiagnosticPosition pos, Symbol location, Type site, Name name, List<Type> argtypes, List<Type> typeargtypes) { 4747 return delegatedError.getDiagnostic(dkind, pos, location, site, name, argtypes, typeargtypes); 4748 } 4749 } 4750 4751 /** 4752 * BadMethodReferenceError error class indicating that a method reference symbol has been found, 4753 * but with the wrong staticness. 4754 */ 4755 class BadMethodReferenceError extends StaticError { 4756 4757 boolean unboundLookup; 4758 4759 public BadMethodReferenceError(Symbol sym, boolean unboundLookup) { 4760 super(sym); 4761 this.unboundLookup = unboundLookup; 4762 } 4763 4764 @Override 4765 JCDiagnostic getDiagnostic(DiagnosticType dkind, DiagnosticPosition pos, Symbol location, Type site, Name name, List<Type> argtypes, List<Type> typeargtypes) { 4766 final String key; 4767 if (!unboundLookup) { 4768 key = "bad.static.method.in.bound.lookup"; 4769 } else if (sym.isStatic()) { 4770 key = "bad.static.method.in.unbound.lookup"; 4771 } else { 4772 key = "bad.instance.method.in.unbound.lookup"; 4773 } 4774 return sym.kind.isResolutionError() ? 4775 ((ResolveError)sym).getDiagnostic(dkind, pos, location, site, name, argtypes, typeargtypes) : 4776 diags.create(dkind, log.currentSource(), pos, key, Kinds.kindName(sym), sym); 4777 } 4778 } 4779 4780 /** 4781 * BadConstructorReferenceError error class indicating that a constructor reference symbol has been found, 4782 * but pointing to a class for which an enclosing instance is not available. 4783 */ 4784 class BadConstructorReferenceError extends InvalidSymbolError { 4785 4786 public BadConstructorReferenceError(Symbol sym) { 4787 super(MISSING_ENCL, sym, "BadConstructorReferenceError"); 4788 } 4789 4790 @Override 4791 JCDiagnostic getDiagnostic(DiagnosticType dkind, DiagnosticPosition pos, Symbol location, Type site, Name name, List<Type> argtypes, List<Type> typeargtypes) { 4792 return diags.create(dkind, log.currentSource(), pos, 4793 "cant.access.inner.cls.constr", site.tsym.name, argtypes, site.getEnclosingType()); 4794 } 4795 } 4796 4797 class BadClassFileError extends InvalidSymbolError { 4798 4799 private final CompletionFailure ex; 4800 4801 public BadClassFileError(CompletionFailure ex) { 4802 super(HIDDEN, ex.sym, "BadClassFileError"); 4803 this.name = sym.name; 4804 this.ex = ex; 4805 } 4806 4807 @Override 4808 JCDiagnostic getDiagnostic(DiagnosticType dkind, DiagnosticPosition pos, Symbol location, Type site, Name name, List<Type> argtypes, List<Type> typeargtypes) { 4809 JCDiagnostic d = diags.create(dkind, log.currentSource(), pos, 4810 "cant.access", ex.sym, ex.getDetailValue()); 4811 4812 d.setFlag(DiagnosticFlag.NON_DEFERRABLE); 4813 return d; 4814 } 4815 4816 } 4817 4818 /** 4819 * Helper class for method resolution diagnostic simplification. 4820 * Certain resolution diagnostic are rewritten as simpler diagnostic 4821 * where the enclosing resolution diagnostic (i.e. 'inapplicable method') 4822 * is stripped away, as it doesn't carry additional info. The logic 4823 * for matching a given diagnostic is given in terms of a template 4824 * hierarchy: a diagnostic template can be specified programmatically, 4825 * so that only certain diagnostics are matched. Each templete is then 4826 * associated with a rewriter object that carries out the task of rewtiting 4827 * the diagnostic to a simpler one. 4828 */ 4829 static class MethodResolutionDiagHelper { 4830 4831 /** 4832 * A diagnostic rewriter transforms a method resolution diagnostic 4833 * into a simpler one 4834 */ 4835 interface DiagnosticRewriter { 4836 JCDiagnostic rewriteDiagnostic(JCDiagnostic.Factory diags, 4837 DiagnosticPosition preferredPos, DiagnosticSource preferredSource, 4838 DiagnosticType preferredKind, JCDiagnostic d); 4839 } 4840 4841 /** 4842 * A diagnostic template is made up of two ingredients: (i) a regular 4843 * expression for matching a diagnostic key and (ii) a list of sub-templates 4844 * for matching diagnostic arguments. 4845 */ 4846 static class Template { 4847 4848 /** regex used to match diag key */ 4849 String regex; 4850 4851 /** templates used to match diagnostic args */ 4852 Template[] subTemplates; 4853 4854 Template(String key, Template... subTemplates) { 4855 this.regex = key; 4856 this.subTemplates = subTemplates; 4857 } 4858 4859 /** 4860 * Returns true if the regex matches the diagnostic key and if 4861 * all diagnostic arguments are matches by corresponding sub-templates. 4862 */ 4863 boolean matches(Object o) { 4864 JCDiagnostic d = (JCDiagnostic)o; 4865 Object[] args = d.getArgs(); 4866 if (!d.getCode().matches(regex) || 4867 subTemplates.length != d.getArgs().length) { 4868 return false; 4869 } 4870 for (int i = 0; i < args.length ; i++) { 4871 if (!subTemplates[i].matches(args[i])) { 4872 return false; 4873 } 4874 } 4875 return true; 4876 } 4877 } 4878 4879 /** 4880 * Common rewriter for all argument mismatch simplifications. 4881 */ 4882 static class ArgMismatchRewriter implements DiagnosticRewriter { 4883 4884 /** the index of the subdiagnostic to be used as primary. */ 4885 int causeIndex; 4886 4887 public ArgMismatchRewriter(int causeIndex) { 4888 this.causeIndex = causeIndex; 4889 } 4890 4891 @Override 4892 public JCDiagnostic rewriteDiagnostic(JCDiagnostic.Factory diags, 4893 DiagnosticPosition preferredPos, DiagnosticSource preferredSource, 4894 DiagnosticType preferredKind, JCDiagnostic d) { 4895 JCDiagnostic cause = (JCDiagnostic)d.getArgs()[causeIndex]; 4896 DiagnosticPosition pos = d.getDiagnosticPosition(); 4897 if (pos == null) { 4898 pos = preferredPos; 4899 } 4900 return diags.create(preferredKind, preferredSource, pos, 4901 "prob.found.req", cause); 4902 } 4903 } 4904 4905 /** a dummy template that match any diagnostic argument */ 4906 static final Template skip = new Template("") { 4907 @Override 4908 boolean matches(Object d) { 4909 return true; 4910 } 4911 }; 4912 4913 /** template for matching inference-free arguments mismatch failures */ 4914 static final Template argMismatchTemplate = new Template(MethodCheckDiag.ARG_MISMATCH.regex(), skip); 4915 4916 /** template for matching inference related arguments mismatch failures */ 4917 static final Template inferArgMismatchTemplate = new Template(MethodCheckDiag.ARG_MISMATCH.regex(), skip, skip) { 4918 @Override 4919 boolean matches(Object o) { 4920 if (!super.matches(o)) { 4921 return false; 4922 } 4923 JCDiagnostic d = (JCDiagnostic)o; 4924 @SuppressWarnings("unchecked") 4925 List<Type> tvars = (List<Type>)d.getArgs()[0]; 4926 return !containsAny(d, tvars); 4927 } 4928 4929 BiPredicate<Object, List<Type>> containsPredicate = (o, ts) -> { 4930 if (o instanceof Type type) { 4931 return type.containsAny(ts); 4932 } else if (o instanceof JCDiagnostic diagnostic) { 4933 return containsAny(diagnostic, ts); 4934 } else { 4935 return false; 4936 } 4937 }; 4938 4939 boolean containsAny(JCDiagnostic d, List<Type> ts) { 4940 return Stream.of(d.getArgs()) 4941 .anyMatch(o -> containsPredicate.test(o, ts)); 4942 } 4943 }; 4944 4945 /** rewriter map used for method resolution simplification */ 4946 static final Map<Template, DiagnosticRewriter> rewriters = new LinkedHashMap<>(); 4947 4948 static { 4949 rewriters.put(argMismatchTemplate, new ArgMismatchRewriter(0)); 4950 rewriters.put(inferArgMismatchTemplate, new ArgMismatchRewriter(1)); 4951 } 4952 4953 /** 4954 * Main entry point for diagnostic rewriting - given a diagnostic, see if any templates matches it, 4955 * and rewrite it accordingly. 4956 */ 4957 static JCDiagnostic rewrite(JCDiagnostic.Factory diags, DiagnosticPosition pos, DiagnosticSource source, 4958 DiagnosticType dkind, JCDiagnostic d) { 4959 for (Map.Entry<Template, DiagnosticRewriter> _entry : rewriters.entrySet()) { 4960 if (_entry.getKey().matches(d)) { 4961 JCDiagnostic simpleDiag = 4962 _entry.getValue().rewriteDiagnostic(diags, pos, source, dkind, d); 4963 simpleDiag.setFlag(DiagnosticFlag.COMPRESSED); 4964 return simpleDiag; 4965 } 4966 } 4967 return null; 4968 } 4969 } 4970 4971 enum MethodResolutionPhase { 4972 BASIC(false, false), 4973 BOX(true, false), 4974 VARARITY(true, true) { 4975 @Override 4976 public Symbol mergeResults(Symbol bestSoFar, Symbol sym) { 4977 //Check invariants (see {@code LookupHelper.shouldStop}) 4978 Assert.check(bestSoFar.kind.isResolutionError() && bestSoFar.kind != AMBIGUOUS); 4979 if (!sym.kind.isResolutionError()) { 4980 //varargs resolution successful 4981 return sym; 4982 } else { 4983 //pick best error 4984 switch (bestSoFar.kind) { 4985 case WRONG_MTH: 4986 case WRONG_MTHS: 4987 //Override previous errors if they were caused by argument mismatch. 4988 //This generally means preferring current symbols - but we need to pay 4989 //attention to the fact that the varargs lookup returns 'less' candidates 4990 //than the previous rounds, and adjust that accordingly. 4991 switch (sym.kind) { 4992 case WRONG_MTH: 4993 //if the previous round matched more than one method, return that 4994 //result instead 4995 return bestSoFar.kind == WRONG_MTHS ? 4996 bestSoFar : sym; 4997 case ABSENT_MTH: 4998 //do not override erroneous symbol if the arity lookup did not 4999 //match any method 5000 return bestSoFar; 5001 case WRONG_MTHS: 5002 default: 5003 //safe to override 5004 return sym; 5005 } 5006 default: 5007 //otherwise, return first error 5008 return bestSoFar; 5009 } 5010 } 5011 } 5012 }; 5013 5014 final boolean isBoxingRequired; 5015 final boolean isVarargsRequired; 5016 5017 MethodResolutionPhase(boolean isBoxingRequired, boolean isVarargsRequired) { 5018 this.isBoxingRequired = isBoxingRequired; 5019 this.isVarargsRequired = isVarargsRequired; 5020 } 5021 5022 public boolean isBoxingRequired() { 5023 return isBoxingRequired; 5024 } 5025 5026 public boolean isVarargsRequired() { 5027 return isVarargsRequired; 5028 } 5029 5030 public Symbol mergeResults(Symbol prev, Symbol sym) { 5031 return sym; 5032 } 5033 } 5034 5035 final List<MethodResolutionPhase> methodResolutionSteps = List.of(BASIC, BOX, VARARITY); 5036 5037 /** 5038 * A resolution context is used to keep track of intermediate results of 5039 * overload resolution, such as list of method that are not applicable 5040 * (used to generate more precise diagnostics) and so on. Resolution contexts 5041 * can be nested - this means that when each overload resolution routine should 5042 * work within the resolution context it created. 5043 */ 5044 class MethodResolutionContext { 5045 5046 private List<Candidate> candidates = List.nil(); 5047 5048 MethodResolutionPhase step = null; 5049 5050 MethodCheck methodCheck = resolveMethodCheck; 5051 5052 private boolean internalResolution = false; 5053 private DeferredAttr.AttrMode attrMode = DeferredAttr.AttrMode.SPECULATIVE; 5054 5055 void addInapplicableCandidate(Symbol sym, JCDiagnostic details) { 5056 Candidate c = new Candidate(currentResolutionContext.step, sym, details, null); 5057 candidates = candidates.append(c); 5058 } 5059 5060 void addApplicableCandidate(Symbol sym, Type mtype) { 5061 Candidate c = new Candidate(currentResolutionContext.step, sym, null, mtype); 5062 candidates = candidates.append(c); 5063 } 5064 5065 DeferredAttrContext deferredAttrContext(Symbol sym, InferenceContext inferenceContext, ResultInfo pendingResult, Warner warn) { 5066 DeferredAttrContext parent = (pendingResult == null) 5067 ? deferredAttr.emptyDeferredAttrContext 5068 : pendingResult.checkContext.deferredAttrContext(); 5069 return deferredAttr.new DeferredAttrContext(attrMode, sym, step, 5070 inferenceContext, parent, warn); 5071 } 5072 5073 /** 5074 * This class represents an overload resolution candidate. There are two 5075 * kinds of candidates: applicable methods and inapplicable methods; 5076 * applicable methods have a pointer to the instantiated method type, 5077 * while inapplicable candidates contain further details about the 5078 * reason why the method has been considered inapplicable. 5079 */ 5080 @SuppressWarnings("overrides") 5081 class Candidate { 5082 5083 final MethodResolutionPhase step; 5084 final Symbol sym; 5085 final JCDiagnostic details; 5086 final Type mtype; 5087 5088 private Candidate(MethodResolutionPhase step, Symbol sym, JCDiagnostic details, Type mtype) { 5089 this.step = step; 5090 this.sym = sym; 5091 this.details = details; 5092 this.mtype = mtype; 5093 } 5094 5095 boolean isApplicable() { 5096 return mtype != null; 5097 } 5098 } 5099 5100 DeferredAttr.AttrMode attrMode() { 5101 return attrMode; 5102 } 5103 5104 boolean internal() { 5105 return internalResolution; 5106 } 5107 } 5108 5109 MethodResolutionContext currentResolutionContext = null; 5110 }