1 /*
   2  * Copyright (c) 1999, 2025, 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.code;
  27 
  28 import java.lang.annotation.Annotation;
  29 import java.lang.annotation.Inherited;
  30 import java.util.ArrayList;
  31 import java.util.Collections;
  32 import java.util.EnumSet;
  33 import java.util.Map;
  34 import java.util.Set;
  35 import java.util.concurrent.Callable;
  36 import java.util.function.Supplier;
  37 import java.util.function.Predicate;
  38 
  39 import javax.lang.model.element.Element;
  40 import javax.lang.model.element.ElementKind;
  41 import javax.lang.model.element.ElementVisitor;
  42 import javax.lang.model.element.ExecutableElement;
  43 import javax.lang.model.element.Modifier;
  44 import javax.lang.model.element.ModuleElement;
  45 import javax.lang.model.element.NestingKind;
  46 import javax.lang.model.element.PackageElement;
  47 import javax.lang.model.element.RecordComponentElement;
  48 import javax.lang.model.element.TypeElement;
  49 import javax.lang.model.element.TypeParameterElement;
  50 import javax.lang.model.element.VariableElement;
  51 import javax.tools.JavaFileManager;
  52 import javax.tools.JavaFileObject;
  53 
  54 import com.sun.tools.javac.code.Kinds.Kind;
  55 import com.sun.tools.javac.comp.Annotate.AnnotationTypeMetadata;
  56 import com.sun.tools.javac.code.Type.*;
  57 import com.sun.tools.javac.comp.Attr;
  58 import com.sun.tools.javac.comp.AttrContext;
  59 import com.sun.tools.javac.comp.Env;
  60 import com.sun.tools.javac.jvm.*;
  61 import com.sun.tools.javac.jvm.PoolConstant;
  62 import com.sun.tools.javac.tree.JCTree;
  63 import com.sun.tools.javac.tree.JCTree.JCAnnotation;
  64 import com.sun.tools.javac.tree.JCTree.JCFieldAccess;
  65 import com.sun.tools.javac.tree.JCTree.JCVariableDecl;
  66 import com.sun.tools.javac.tree.JCTree.Tag;
  67 import com.sun.tools.javac.util.*;
  68 import com.sun.tools.javac.util.DefinedBy.Api;
  69 import com.sun.tools.javac.util.List;
  70 import com.sun.tools.javac.util.Name;
  71 
  72 import static com.sun.tools.javac.code.Flags.*;
  73 import static com.sun.tools.javac.code.Kinds.*;
  74 import static com.sun.tools.javac.code.Kinds.Kind.*;
  75 import static com.sun.tools.javac.code.Scope.LookupKind.NON_RECURSIVE;
  76 import com.sun.tools.javac.code.Scope.WriteableScope;
  77 import static com.sun.tools.javac.code.TypeTag.CLASS;
  78 import static com.sun.tools.javac.code.TypeTag.FORALL;
  79 import static com.sun.tools.javac.code.TypeTag.TYPEVAR;
  80 import static com.sun.tools.javac.jvm.ByteCodes.iadd;
  81 import static com.sun.tools.javac.jvm.ByteCodes.ishll;
  82 import static com.sun.tools.javac.jvm.ByteCodes.lushrl;
  83 import static com.sun.tools.javac.jvm.ByteCodes.lxor;
  84 import static com.sun.tools.javac.jvm.ByteCodes.string_add;
  85 
  86 /** Root class for Java symbols. It contains subclasses
  87  *  for specific sorts of symbols, such as variables, methods and operators,
  88  *  types, packages. Each subclass is represented as a static inner class
  89  *  inside Symbol.
  90  *
  91  *  <p><b>This is NOT part of any supported API.
  92  *  If you write code that depends on this, you do so at your own risk.
  93  *  This code and its internal interfaces are subject to change or
  94  *  deletion without notice.</b>
  95  */
  96 public abstract class Symbol extends AnnoConstruct implements PoolConstant, Element {
  97 
  98     /** The kind of this symbol.
  99      *  @see Kinds
 100      */
 101     public Kind kind;
 102 
 103     /** The flags of this symbol.
 104      */
 105     public long flags_field;
 106 
 107     /** An accessor method for the flags of this symbol.
 108      *  Flags of class symbols should be accessed through the accessor
 109      *  method to make sure that the class symbol is loaded.
 110      */
 111     public long flags() { return flags_field; }
 112 
 113     /** The name of this symbol in Utf8 representation.
 114      */
 115     public Name name;
 116 
 117     /** The type of this symbol.
 118      */
 119     public Type type;
 120 
 121     /** The owner of this symbol.
 122      */
 123     public Symbol owner;
 124 
 125     /** The completer of this symbol.
 126      * This should never equal null (NULL_COMPLETER should be used instead).
 127      */
 128     public Completer completer;
 129 
 130     /** A cache for the type erasure of this symbol.
 131      */
 132     public Type erasure_field;
 133 
 134     // <editor-fold defaultstate="collapsed" desc="annotations">
 135 
 136     /** The attributes of this symbol are contained in this
 137      * SymbolMetadata. The SymbolMetadata instance is NOT immutable.
 138      */
 139     protected SymbolMetadata metadata;
 140 
 141 
 142     /** An accessor method for the attributes of this symbol.
 143      *  Attributes of class symbols should be accessed through the accessor
 144      *  method to make sure that the class symbol is loaded.
 145      */
 146     public List<Attribute.Compound> getRawAttributes() {
 147         return (metadata == null)
 148                 ? List.nil()
 149                 : metadata.getDeclarationAttributes();
 150     }
 151 
 152     /** An accessor method for the type attributes of this symbol.
 153      *  Attributes of class symbols should be accessed through the accessor
 154      *  method to make sure that the class symbol is loaded.
 155      */
 156     public List<Attribute.TypeCompound> getRawTypeAttributes() {
 157         return (metadata == null)
 158                 ? List.nil()
 159                 : metadata.getTypeAttributes();
 160     }
 161 
 162     /** Fetch a particular annotation from a symbol. */
 163     public Attribute.Compound attribute(Symbol anno) {
 164         for (Attribute.Compound a : getRawAttributes()) {
 165             if (a.type.tsym == anno) return a;
 166         }
 167         return null;
 168     }
 169 
 170     public boolean annotationsPendingCompletion() {
 171         return metadata == null ? false : metadata.pendingCompletion();
 172     }
 173 
 174     public void appendAttributes(List<Attribute.Compound> l) {
 175         if (l.nonEmpty()) {
 176             initedMetadata().append(l);
 177         }
 178     }
 179 
 180     public void appendClassInitTypeAttributes(List<Attribute.TypeCompound> l) {
 181         if (l.nonEmpty()) {
 182             initedMetadata().appendClassInitTypeAttributes(l);
 183         }
 184     }
 185 
 186     public void appendInitTypeAttributes(List<Attribute.TypeCompound> l) {
 187         if (l.nonEmpty()) {
 188             initedMetadata().appendInitTypeAttributes(l);
 189         }
 190     }
 191 
 192     public void appendUniqueTypeAttributes(List<Attribute.TypeCompound> l) {
 193         if (l.nonEmpty()) {
 194             initedMetadata().appendUniqueTypes(l);
 195         }
 196     }
 197 
 198     public List<Attribute.TypeCompound> getClassInitTypeAttributes() {
 199         return (metadata == null)
 200                 ? List.nil()
 201                 : metadata.getClassInitTypeAttributes();
 202     }
 203 
 204     public List<Attribute.TypeCompound> getInitTypeAttributes() {
 205         return (metadata == null)
 206                 ? List.nil()
 207                 : metadata.getInitTypeAttributes();
 208     }
 209 
 210     public void setInitTypeAttributes(List<Attribute.TypeCompound> l) {
 211         initedMetadata().setInitTypeAttributes(l);
 212     }
 213 
 214     public void setClassInitTypeAttributes(List<Attribute.TypeCompound> l) {
 215         initedMetadata().setClassInitTypeAttributes(l);
 216     }
 217 
 218     public List<Attribute.Compound> getDeclarationAttributes() {
 219         return (metadata == null)
 220                 ? List.nil()
 221                 : metadata.getDeclarationAttributes();
 222     }
 223 
 224     public boolean hasAnnotations() {
 225         return (metadata != null && !metadata.isEmpty());
 226     }
 227 
 228     public boolean hasTypeAnnotations() {
 229         return (metadata != null && !metadata.isTypesEmpty());
 230     }
 231 
 232     public boolean isCompleted() {
 233         return completer.isTerminal();
 234     }
 235 
 236     public void prependAttributes(List<Attribute.Compound> l) {
 237         if (l.nonEmpty()) {
 238             initedMetadata().prepend(l);
 239         }
 240     }
 241 
 242     public void resetAnnotations() {
 243         initedMetadata().reset();
 244     }
 245 
 246     public void setAttributes(Symbol other) {
 247         if (metadata != null || other.metadata != null) {
 248             initedMetadata().setAttributes(other.metadata);
 249         }
 250     }
 251 
 252     public void setDeclarationAttributes(List<Attribute.Compound> a) {
 253         if (metadata != null || a.nonEmpty()) {
 254             initedMetadata().setDeclarationAttributes(a);
 255         }
 256     }
 257 
 258     public void setTypeAttributes(List<Attribute.TypeCompound> a) {
 259         if (metadata != null || a.nonEmpty()) {
 260             if (metadata == null)
 261                 metadata = new SymbolMetadata(this);
 262             metadata.setTypeAttributes(a);
 263         }
 264     }
 265 
 266     private SymbolMetadata initedMetadata() {
 267         if (metadata == null)
 268             metadata = new SymbolMetadata(this);
 269         return metadata;
 270     }
 271 
 272     /** This method is intended for debugging only. */
 273     public SymbolMetadata getMetadata() {
 274         return metadata;
 275     }
 276 
 277     // </editor-fold>
 278 
 279     /** Construct a symbol with given kind, flags, name, type and owner.
 280      */
 281     public Symbol(Kind kind, long flags, Name name, Type type, Symbol owner) {
 282         this.kind = kind;
 283         this.flags_field = flags;
 284         this.type = type;
 285         this.owner = owner;
 286         this.completer = Completer.NULL_COMPLETER;
 287         this.erasure_field = null;
 288         this.name = name;
 289     }
 290 
 291     @Override
 292     public int poolTag() {
 293         throw new AssertionError("Invalid pool entry");
 294     }
 295 
 296     /** Clone this symbol with new owner.
 297      *  Legal only for fields and methods.
 298      */
 299     public Symbol clone(Symbol newOwner) {
 300         throw new AssertionError();
 301     }
 302 
 303     public <R, P> R accept(Symbol.Visitor<R, P> v, P p) {
 304         return v.visitSymbol(this, p);
 305     }
 306 
 307     /** The Java source which this symbol represents.
 308      *  A description of this symbol; overrides Object.
 309      */
 310     public String toString() {
 311         return name.toString();
 312     }
 313 
 314     /** A Java source description of the location of this symbol; used for
 315      *  error reporting.
 316      *
 317      * @return null if the symbol is a package or a toplevel class defined in
 318      * the default package; otherwise, the owner symbol is returned
 319      */
 320     public Symbol location() {
 321         if (owner.name == null || (owner.name.isEmpty() &&
 322                                    (owner.flags() & BLOCK) == 0 &&
 323                                    owner.kind != PCK &&
 324                                    owner.kind != TYP)) {
 325             return null;
 326         }
 327         return owner;
 328     }
 329 
 330     public Symbol location(Type site, Types types) {
 331         if (owner.name == null || owner.name.isEmpty()) {
 332             return location();
 333         }
 334         if (owner.type.hasTag(CLASS)) {
 335             Type ownertype = types.asOuterSuper(site, owner);
 336             if (ownertype != null) return ownertype.tsym;
 337         }
 338         return owner;
 339     }
 340 
 341     public Symbol baseSymbol() {
 342         return this;
 343     }
 344 
 345     /** The symbol's erased type.
 346      */
 347     public Type erasure(Types types) {
 348         if (erasure_field == null)
 349             erasure_field = types.erasure(type);
 350         return erasure_field;
 351     }
 352 
 353     /** The external type of a symbol. This is the symbol's erased type
 354      *  except for constructors of inner classes which get the enclosing
 355      *  instance class added as first argument.
 356      */
 357     public Type externalType(Types types) {
 358         Type t = erasure(types);
 359         if (name == name.table.names.init && owner.hasOuterInstance()) {
 360             Type outerThisType = owner.innermostAccessibleEnclosingClass().erasure(types);
 361             return new MethodType(t.getParameterTypes().prepend(outerThisType),
 362                                   t.getReturnType(),
 363                                   t.getThrownTypes(),
 364                                   t.tsym);
 365         } else {
 366             return t;
 367         }
 368     }
 369 
 370     public boolean isDeprecated() {
 371         return (flags_field & DEPRECATED) != 0;
 372     }
 373 
 374     public boolean hasDeprecatedAnnotation() {
 375         return (flags_field & DEPRECATED_ANNOTATION) != 0;
 376     }
 377 
 378     public boolean isDeprecatedForRemoval() {
 379         return (flags_field & DEPRECATED_REMOVAL) != 0;
 380     }
 381 
 382     public boolean isPreviewApi() {
 383         return (flags_field & PREVIEW_API) != 0;
 384     }
 385 
 386     public boolean isDeprecatableViaAnnotation() {
 387         switch (getKind()) {
 388             case LOCAL_VARIABLE:
 389             case PACKAGE:
 390             case PARAMETER:
 391             case RESOURCE_VARIABLE:
 392             case EXCEPTION_PARAMETER:
 393                 return false;
 394             default:
 395                 return true;
 396         }
 397     }
 398 
 399     public boolean isStatic() {
 400         return
 401             (flags() & STATIC) != 0 ||
 402             (owner.flags() & INTERFACE) != 0 && kind != MTH &&
 403              name != name.table.names._this;
 404     }
 405 
 406     public boolean isStrict() {
 407         return (flags() & STRICT) != 0;
 408     }
 409 
 410     public boolean isStrictInstance() {
 411         return (flags() & STRICT) != 0 && (flags() & STATIC) == 0;
 412     }
 413 
 414     public boolean hasStrict() {
 415         return (flags() & HAS_STRICT) != 0;
 416     }
 417 
 418     public boolean isInterface() {
 419         return (flags_field & INTERFACE) != 0;
 420     }
 421 
 422     public boolean isAbstract() {
 423         return (flags_field & ABSTRACT) != 0;
 424     }
 425 
 426     public boolean isPrivate() {
 427         return (flags_field & Flags.AccessFlags) == PRIVATE;
 428     }
 429 
 430     public boolean isValueClass() {
 431         return (flags_field & VALUE_CLASS) != 0;
 432     }
 433 
 434     public boolean isIdentityClass() {
 435         return !isInterface() && (flags_field & IDENTITY_TYPE) != 0;
 436     }
 437 
 438     public boolean isPublic() {
 439         return (flags_field & Flags.AccessFlags) == PUBLIC;
 440     }
 441 
 442     public boolean isEnum() {
 443         return (flags() & ENUM) != 0;
 444     }
 445 
 446     public boolean isSealed() {
 447         return (flags_field & SEALED) != 0;
 448     }
 449 
 450     public boolean isNonSealed() {
 451         return (flags_field & NON_SEALED) != 0;
 452     }
 453 
 454     public boolean isFinal() {
 455         return (flags_field & FINAL) != 0;
 456     }
 457 
 458     public boolean isImplicit() {
 459         return (flags_field & IMPLICIT_CLASS) != 0;
 460     }
 461 
 462    /** Is this symbol declared (directly or indirectly) local
 463      *  to a method or variable initializer?
 464      *  Also includes fields of inner classes which are in
 465      *  turn local to a method or variable initializer.
 466      */
 467     public boolean isDirectlyOrIndirectlyLocal() {
 468         return
 469             (owner.kind.matches(KindSelector.VAL_MTH) ||
 470              (owner.kind == TYP && owner.isDirectlyOrIndirectlyLocal()));
 471     }
 472 
 473     /** Has this symbol an empty name? This includes anonymous
 474      *  inner classes.
 475      */
 476     public boolean isAnonymous() {
 477         return name.isEmpty();
 478     }
 479 
 480     /** Is this symbol a constructor?
 481      */
 482     public boolean isConstructor() {
 483         return name == name.table.names.init;
 484     }
 485 
 486     public boolean isDynamic() {
 487         return false;
 488     }
 489 
 490     /** The fully qualified name of this symbol.
 491      *  This is the same as the symbol's name except for class symbols,
 492      *  which are handled separately.
 493      */
 494     public Name getQualifiedName() {
 495         return name;
 496     }
 497 
 498     /** The fully qualified name of this symbol after converting to flat
 499      *  representation. This is the same as the symbol's name except for
 500      *  class symbols, which are handled separately.
 501      */
 502     public Name flatName() {
 503         return getQualifiedName();
 504     }
 505 
 506     /** If this is a class or package, its members, otherwise null.
 507      */
 508     public WriteableScope members() {
 509         return null;
 510     }
 511 
 512     /** A class is an inner class if it it has an enclosing instance class.
 513      */
 514     public boolean isInner() {
 515         return kind == TYP && type.getEnclosingType().hasTag(CLASS);
 516     }
 517 
 518     /** An inner class has an outer instance if it is not an interface, enum or record,
 519      *  it has an enclosing instance class which might be referenced from the class.
 520      *  Nested classes can see instance members of their enclosing class.
 521      *  Their constructors carry an additional this$n parameter, inserted
 522      *  implicitly by the compiler.
 523      *
 524      *  @see #isInner
 525      */
 526     public boolean hasOuterInstance() {
 527         return
 528             type.getEnclosingType().hasTag(CLASS) && (flags() & (INTERFACE | ENUM | RECORD)) == 0 &&
 529                     ((flags() & NOOUTERTHIS) == 0 || type.getEnclosingType().tsym.hasOuterInstance());
 530     }
 531 
 532     /** If the class containing this symbol is a local or an anonymous class, then it might be
 533      *  defined inside one or more pre-construction contexts, for which the corresponding enclosing
 534      *  instance is considered inaccessible. This method return the class symbol corresponding to the
 535      *  innermost enclosing type that is accessible from this symbol's class. Note: this method should
 536      *  only be called after checking that {@link #hasOuterInstance()} returns {@code true}.
 537      */
 538     public ClassSymbol innermostAccessibleEnclosingClass() {
 539         Assert.check(enclClass().hasOuterInstance());
 540         Type current = enclClass().type;
 541         while ((current.tsym.flags() & NOOUTERTHIS) != 0) {
 542             current = current.getEnclosingType();
 543         }
 544         return (ClassSymbol) current.getEnclosingType().tsym;
 545     }
 546 
 547     /** The closest enclosing class of this symbol's declaration.
 548      *  Warning: this (misnamed) method returns the receiver itself
 549      *  when the receiver is a class (as opposed to its enclosing
 550      *  class as one may be misled to believe.)
 551      */
 552     public ClassSymbol enclClass() {
 553         Symbol c = this;
 554         while (c != null &&
 555                (!c.kind.matches(KindSelector.TYP) || !c.type.hasTag(CLASS))) {
 556             c = c.owner;
 557         }
 558         return (ClassSymbol)c;
 559     }
 560 
 561     /** The outermost class which indirectly owns this symbol.
 562      */
 563     public ClassSymbol outermostClass() {
 564         Symbol sym = this;
 565         Symbol prev = null;
 566         while (sym.kind != PCK) {
 567             prev = sym;
 568             sym = sym.owner;
 569         }
 570         return (ClassSymbol) prev;
 571     }
 572 
 573     /** The package which indirectly owns this symbol.
 574      */
 575     public PackageSymbol packge() {
 576         Symbol sym = this;
 577         while (sym.kind != PCK) {
 578             sym = sym.owner;
 579         }
 580         return (PackageSymbol) sym;
 581     }
 582 
 583     /** Is this symbol a subclass of `base'? Only defined for ClassSymbols.
 584      */
 585     public boolean isSubClass(Symbol base, Types types) {
 586         throw new AssertionError("isSubClass " + this);
 587     }
 588 
 589     /** Fully check membership: hierarchy, protection, and hiding.
 590      *  Does not exclude methods not inherited due to overriding.
 591      */
 592     public boolean isMemberOf(TypeSymbol clazz, Types types) {
 593         return
 594             owner == clazz ||
 595             clazz.isSubClass(owner, types) &&
 596             isInheritedIn(clazz, types) &&
 597             !hiddenIn((ClassSymbol)clazz, types);
 598     }
 599 
 600     /** Is this symbol the same as or enclosed by the given class? */
 601     public boolean isEnclosedBy(ClassSymbol clazz) {
 602         for (Symbol sym = this; sym.kind != PCK; sym = sym.owner)
 603             if (sym == clazz) return true;
 604         return false;
 605     }
 606 
 607     private boolean hiddenIn(ClassSymbol clazz, Types types) {
 608         Symbol sym = hiddenInInternal(clazz, types);
 609         Assert.check(sym != null, "the result of hiddenInInternal() can't be null");
 610         /* If we find the current symbol then there is no symbol hiding it
 611          */
 612         return sym != this;
 613     }
 614 
 615     /** This method looks in the supertypes graph that has the current class as the
 616      * initial node, till it finds the current symbol or another symbol that hides it.
 617      * If the current class has more than one supertype (extends one class and
 618      * implements one or more interfaces) then null can be returned, meaning that
 619      * a wrong path in the supertypes graph was selected. Null can only be returned
 620      * as a temporary value, as a result of the recursive call.
 621      */
 622     private Symbol hiddenInInternal(ClassSymbol currentClass, Types types) {
 623         if (currentClass == owner) {
 624             return this;
 625         }
 626         for (Symbol sym : currentClass.members().getSymbolsByName(name)) {
 627             if (sym.kind == kind &&
 628                     (kind != MTH ||
 629                     (sym.flags() & STATIC) != 0 &&
 630                     types.isSubSignature(sym.type, type))) {
 631                 return sym;
 632             }
 633         }
 634         Symbol hiddenSym = null;
 635         for (Type st : types.interfaces(currentClass.type)
 636                 .prepend(types.supertype(currentClass.type))) {
 637             if (st != null && (st.hasTag(CLASS))) {
 638                 Symbol sym = hiddenInInternal((ClassSymbol)st.tsym, types);
 639                 if (sym == this) {
 640                     return this;
 641                 } else if (sym != null) {
 642                     hiddenSym = sym;
 643                 }
 644             }
 645         }
 646         return hiddenSym;
 647     }
 648 
 649     /** Is this symbol accessible in a given class?
 650      *  PRE: If symbol's owner is a interface,
 651      *       it is already assumed that the interface is a superinterface
 652      *       the given class.
 653      *  @param clazz  The class for which we want to establish membership.
 654      *                This must be a subclass of the member's owner.
 655      */
 656     public final boolean isAccessibleIn(Symbol clazz, Types types) {
 657         switch ((int)(flags_field & Flags.AccessFlags)) {
 658         default: // error recovery
 659         case PUBLIC:
 660             return true;
 661         case PRIVATE:
 662             return this.owner == clazz;
 663         case PROTECTED:
 664             // we model interfaces as extending Object
 665             return (clazz.flags() & INTERFACE) == 0;
 666         case 0:
 667             PackageSymbol thisPackage = this.packge();
 668             for (Symbol sup = clazz;
 669                  sup != null && sup != this.owner;
 670                  sup = types.supertype(sup.type).tsym) {
 671                 while (sup.type.hasTag(TYPEVAR))
 672                     sup = sup.type.getUpperBound().tsym;
 673                 if (sup.type.isErroneous())
 674                     return true; // error recovery
 675                 if ((sup.flags() & COMPOUND) != 0)
 676                     continue;
 677                 if (sup.packge() != thisPackage)
 678                     return false;
 679             }
 680             return (clazz.flags() & INTERFACE) == 0;
 681         }
 682     }
 683 
 684     /** Is this symbol inherited into a given class?
 685      *  PRE: If symbol's owner is a interface,
 686      *       it is already assumed that the interface is a superinterface
 687      *       of the given class.
 688      *  @param clazz  The class for which we want to establish membership.
 689      *                This must be a subclass of the member's owner.
 690      */
 691     public boolean isInheritedIn(Symbol clazz, Types types) {
 692         return isAccessibleIn(clazz, types);
 693     }
 694 
 695     /** The (variable or method) symbol seen as a member of given
 696      *  class type`site' (this might change the symbol's type).
 697      *  This is used exclusively for producing diagnostics.
 698      */
 699     public Symbol asMemberOf(Type site, Types types) {
 700         throw new AssertionError();
 701     }
 702 
 703     /** Does this method symbol override `other' symbol, when both are seen as
 704      *  members of class `origin'?  It is assumed that _other is a member
 705      *  of origin.
 706      *
 707      *  It is assumed that both symbols have the same name.  The static
 708      *  modifier is ignored for this test.
 709      *
 710      *  See JLS 8.4.8.1 (without transitivity) and 8.4.8.4
 711      */
 712     public boolean overrides(Symbol _other, TypeSymbol origin, Types types, boolean checkResult) {
 713         return false;
 714     }
 715 
 716     /** Complete the elaboration of this symbol's definition.
 717      */
 718     public void complete() throws CompletionFailure {
 719         if (completer != Completer.NULL_COMPLETER) {
 720             Completer c = completer;
 721             completer = Completer.NULL_COMPLETER;
 722             c.complete(this);
 723         }
 724     }
 725 
 726     public void apiComplete() throws CompletionFailure {
 727         try {
 728             complete();
 729         } catch (CompletionFailure cf) {
 730             cf.dcfh.handleAPICompletionFailure(cf);
 731         }
 732     }
 733 
 734     /** True if the symbol represents an entity that exists.
 735      */
 736     public boolean exists() {
 737         return true;
 738     }
 739 
 740     @DefinedBy(Api.LANGUAGE_MODEL)
 741     public Type asType() {
 742         return type;
 743     }
 744 
 745     @DefinedBy(Api.LANGUAGE_MODEL)
 746     public Symbol getEnclosingElement() {
 747         return owner;
 748     }
 749 
 750     @DefinedBy(Api.LANGUAGE_MODEL)
 751     public ElementKind getKind() {
 752         return ElementKind.OTHER;       // most unkind
 753     }
 754 
 755     @DefinedBy(Api.LANGUAGE_MODEL)
 756     public Set<Modifier> getModifiers() {
 757         apiComplete();
 758         return Flags.asModifierSet(flags());
 759     }
 760 
 761     @DefinedBy(Api.LANGUAGE_MODEL)
 762     public Name getSimpleName() {
 763         return name;
 764     }
 765 
 766     /**
 767      * This is the implementation for {@code
 768      * javax.lang.model.element.Element.getAnnotationMirrors()}.
 769      */
 770     @Override @DefinedBy(Api.LANGUAGE_MODEL)
 771     public List<Attribute.Compound> getAnnotationMirrors() {
 772         apiComplete();
 773         return getRawAttributes();
 774     }
 775 
 776 
 777     // TODO: getEnclosedElements should return a javac List, fix in FilteredMemberList
 778     @DefinedBy(Api.LANGUAGE_MODEL)
 779     public java.util.List<Symbol> getEnclosedElements() {
 780         return List.nil();
 781     }
 782 
 783     public List<TypeVariableSymbol> getTypeParameters() {
 784         ListBuffer<TypeVariableSymbol> l = new ListBuffer<>();
 785         for (Type t : type.getTypeArguments()) {
 786             Assert.check(t.tsym.getKind() == ElementKind.TYPE_PARAMETER);
 787             l.append((TypeVariableSymbol)t.tsym);
 788         }
 789         return l.toList();
 790     }
 791 
 792     public static class DelegatedSymbol<T extends Symbol> extends Symbol {
 793         protected T other;
 794         public DelegatedSymbol(T other) {
 795             super(other.kind, other.flags_field, other.name, other.type, other.owner);
 796             this.other = other;
 797         }
 798         public String toString() { return other.toString(); }
 799         public Symbol location() { return other.location(); }
 800         public Symbol location(Type site, Types types) { return other.location(site, types); }
 801         public Symbol baseSymbol() { return other; }
 802         public Type erasure(Types types) { return other.erasure(types); }
 803         public Type externalType(Types types) { return other.externalType(types); }
 804         public boolean isDirectlyOrIndirectlyLocal() { return other.isDirectlyOrIndirectlyLocal(); }
 805         public boolean isConstructor() { return other.isConstructor(); }
 806         public Name getQualifiedName() { return other.getQualifiedName(); }
 807         public Name flatName() { return other.flatName(); }
 808         public WriteableScope members() { return other.members(); }
 809         public boolean isInner() { return other.isInner(); }
 810         public boolean hasOuterInstance() { return other.hasOuterInstance(); }
 811         public ClassSymbol enclClass() { return other.enclClass(); }
 812         public ClassSymbol outermostClass() { return other.outermostClass(); }
 813         public PackageSymbol packge() { return other.packge(); }
 814         public boolean isSubClass(Symbol base, Types types) { return other.isSubClass(base, types); }
 815         public boolean isMemberOf(TypeSymbol clazz, Types types) { return other.isMemberOf(clazz, types); }
 816         public boolean isEnclosedBy(ClassSymbol clazz) { return other.isEnclosedBy(clazz); }
 817         public boolean isInheritedIn(Symbol clazz, Types types) { return other.isInheritedIn(clazz, types); }
 818         public Symbol asMemberOf(Type site, Types types) { return other.asMemberOf(site, types); }
 819         public void complete() throws CompletionFailure { other.complete(); }
 820 
 821         @DefinedBy(Api.LANGUAGE_MODEL)
 822         public <R, P> R accept(ElementVisitor<R, P> v, P p) {
 823             return other.accept(v, p);
 824         }
 825 
 826         public <R, P> R accept(Symbol.Visitor<R, P> v, P p) {
 827             return v.visitSymbol(other, p);
 828         }
 829 
 830         public T getUnderlyingSymbol() {
 831             return other;
 832         }
 833     }
 834 
 835     /** A base class for Symbols representing types.
 836      */
 837     public abstract static class TypeSymbol extends Symbol {
 838         public TypeSymbol(Kind kind, long flags, Name name, Type type, Symbol owner) {
 839             super(kind, flags, name, type, owner);
 840         }
 841         /** form a fully qualified name from a name and an owner
 842          */
 843         public static Name formFullName(Name name, Symbol owner) {
 844             if (owner == null) return name;
 845             if ((owner.kind != ERR) &&
 846                 (owner.kind.matches(KindSelector.VAL_MTH) ||
 847                  (owner.kind == TYP && owner.type.hasTag(TYPEVAR))
 848                  )) return name;
 849             Name prefix = owner.getQualifiedName();
 850             if (prefix == null || prefix == prefix.table.names.empty)
 851                 return name;
 852             else return prefix.append('.', name);
 853         }
 854 
 855         /** form a fully qualified name from a name and an owner, after
 856          *  converting to flat representation
 857          */
 858         public static Name formFlatName(Name name, Symbol owner) {
 859             if (owner == null || owner.kind.matches(KindSelector.VAL_MTH) ||
 860                 (owner.kind == TYP && owner.type.hasTag(TYPEVAR))
 861                 ) return name;
 862             char sep = owner.kind == TYP ? '$' : '.';
 863             Name prefix = owner.flatName();
 864             if (prefix == null || prefix == prefix.table.names.empty)
 865                 return name;
 866             else return prefix.append(sep, name);
 867         }
 868 
 869         /**
 870          * A partial ordering between type symbols that refines the
 871          * class inheritance graph.
 872          *
 873          * Type variables always precede other kinds of symbols.
 874          */
 875         public final boolean precedes(TypeSymbol that, Types types) {
 876             if (this == that)
 877                 return false;
 878             if (type.hasTag(that.type.getTag())) {
 879                 if (type.hasTag(CLASS)) {
 880                     return
 881                         types.rank(that.type) < types.rank(this.type) ||
 882                         (types.rank(that.type) == types.rank(this.type) &&
 883                          this.getQualifiedName().compareTo(that.getQualifiedName()) < 0);
 884                 } else if (type.hasTag(TYPEVAR)) {
 885                     return types.isSubtype(this.type, that.type);
 886                 }
 887             }
 888             return type.hasTag(TYPEVAR);
 889         }
 890 
 891         @Override @DefinedBy(Api.LANGUAGE_MODEL)
 892         public List<Symbol> getEnclosedElements() {
 893             List<Symbol> list = List.nil();
 894             if (kind == TYP && type.hasTag(TYPEVAR)) {
 895                 return list;
 896             }
 897             apiComplete();
 898             for (Symbol sym : members().getSymbols(NON_RECURSIVE)) {
 899                 sym.apiComplete();
 900                 if ((sym.flags() & SYNTHETIC) == 0 && sym.owner == this && sym.kind != ERR) {
 901                     list = list.prepend(sym);
 902                 }
 903             }
 904             return list;
 905         }
 906 
 907         public AnnotationTypeMetadata getAnnotationTypeMetadata() {
 908             Assert.error("Only on ClassSymbol");
 909             return null; //unreachable
 910         }
 911 
 912         public boolean isAnnotationType() { return false; }
 913 
 914         @Override
 915         public <R, P> R accept(Symbol.Visitor<R, P> v, P p) {
 916             return v.visitTypeSymbol(this, p);
 917         }
 918     }
 919 
 920     /**
 921      * Type variables are represented by instances of this class.
 922      */
 923     public static class TypeVariableSymbol
 924             extends TypeSymbol implements TypeParameterElement {
 925 
 926         public TypeVariableSymbol(long flags, Name name, Type type, Symbol owner) {
 927             super(TYP, flags, name, type, owner);
 928         }
 929 
 930         @DefinedBy(Api.LANGUAGE_MODEL)
 931         public ElementKind getKind() {
 932             return ElementKind.TYPE_PARAMETER;
 933         }
 934 
 935         @Override @DefinedBy(Api.LANGUAGE_MODEL)
 936         public Symbol getGenericElement() {
 937             return owner;
 938         }
 939 
 940         @DefinedBy(Api.LANGUAGE_MODEL)
 941         public List<Type> getBounds() {
 942             TypeVar t = (TypeVar)type;
 943             Type bound = t.getUpperBound();
 944             if (!bound.isCompound())
 945                 return List.of(bound);
 946             ClassType ct = (ClassType)bound;
 947             if (!ct.tsym.erasure_field.isInterface()) {
 948                 return ct.interfaces_field.prepend(ct.supertype_field);
 949             } else {
 950                 // No superclass was given in bounds.
 951                 // In this case, supertype is Object, erasure is first interface.
 952                 return ct.interfaces_field;
 953             }
 954         }
 955 
 956         @Override @DefinedBy(Api.LANGUAGE_MODEL)
 957         public List<Attribute.Compound> getAnnotationMirrors() {
 958             // Declaration annotations on type variables are stored in type attributes
 959             // on the owner of the TypeVariableSymbol
 960             List<Attribute.TypeCompound> candidates = owner.getRawTypeAttributes();
 961             int index = owner.getTypeParameters().indexOf(this);
 962             List<Attribute.Compound> res = List.nil();
 963             for (Attribute.TypeCompound a : candidates) {
 964                 if (isCurrentSymbolsAnnotation(a, index))
 965                     res = res.prepend(a);
 966             }
 967 
 968             return res.reverse();
 969         }
 970 
 971         // Helper to getAnnotation[s]
 972         @Override
 973         public <A extends Annotation> Attribute.Compound getAttribute(Class<A> annoType) {
 974             String name = annoType.getName();
 975 
 976             // Declaration annotations on type variables are stored in type attributes
 977             // on the owner of the TypeVariableSymbol
 978             List<Attribute.TypeCompound> candidates = owner.getRawTypeAttributes();
 979             int index = owner.getTypeParameters().indexOf(this);
 980             for (Attribute.TypeCompound anno : candidates)
 981                 if (isCurrentSymbolsAnnotation(anno, index) &&
 982                     name.contentEquals(anno.type.tsym.flatName()))
 983                     return anno;
 984 
 985             return null;
 986         }
 987             //where:
 988             boolean isCurrentSymbolsAnnotation(Attribute.TypeCompound anno, int index) {
 989                 return (anno.position.type == TargetType.CLASS_TYPE_PARAMETER ||
 990                         anno.position.type == TargetType.METHOD_TYPE_PARAMETER) &&
 991                         anno.position.parameter_index == index &&
 992                         anno.type.tsym.flatName() != name.table.names.requiresIdentityInternal;
 993             }
 994 
 995 
 996         @Override @DefinedBy(Api.LANGUAGE_MODEL)
 997         public <R, P> R accept(ElementVisitor<R, P> v, P p) {
 998             return v.visitTypeParameter(this, p);
 999         }
1000     }
1001     /** A class for module symbols.
1002      */
1003     public static class ModuleSymbol extends TypeSymbol
1004             implements ModuleElement {
1005 
1006         public Name version;
1007         public JavaFileManager.Location sourceLocation;
1008         public JavaFileManager.Location classLocation;
1009         public JavaFileManager.Location patchLocation;
1010         public JavaFileManager.Location patchOutputLocation;
1011 
1012         /** All directives, in natural order. */
1013         public List<com.sun.tools.javac.code.Directive> directives;
1014         public List<com.sun.tools.javac.code.Directive.RequiresDirective> requires;
1015         public List<com.sun.tools.javac.code.Directive.ExportsDirective> exports;
1016         public List<com.sun.tools.javac.code.Directive.OpensDirective> opens;
1017         public List<com.sun.tools.javac.code.Directive.ProvidesDirective> provides;
1018         public List<com.sun.tools.javac.code.Directive.UsesDirective> uses;
1019 
1020         public ClassSymbol module_info;
1021 
1022         public PackageSymbol unnamedPackage;
1023         public Map<Name, PackageSymbol> visiblePackages;
1024         public Set<ModuleSymbol> readModules;
1025         public List<Symbol> enclosedPackages = List.nil();
1026 
1027         public Completer usesProvidesCompleter = Completer.NULL_COMPLETER;
1028         public final Set<ModuleFlags> flags = EnumSet.noneOf(ModuleFlags.class);
1029         public final Set<ModuleResolutionFlags> resolutionFlags = EnumSet.noneOf(ModuleResolutionFlags.class);
1030 
1031         /**
1032          * Create a ModuleSymbol with an associated module-info ClassSymbol.
1033          */
1034         public static ModuleSymbol create(Name name, Name module_info) {
1035             ModuleSymbol msym = new ModuleSymbol(name, null);
1036             ClassSymbol info = new ClassSymbol(Flags.MODULE, module_info, msym);
1037             info.fullname = formFullName(module_info, msym);
1038             info.flatname = info.fullname;
1039             info.members_field = WriteableScope.create(info);
1040             msym.module_info = info;
1041             return msym;
1042         }
1043 
1044         @SuppressWarnings("this-escape")
1045         public ModuleSymbol(Name name, Symbol owner) {
1046             super(MDL, 0, name, null, owner);
1047             Assert.checkNonNull(name);
1048             this.type = new ModuleType(this);
1049         }
1050 
1051         @Override
1052         public int poolTag() {
1053             return ClassFile.CONSTANT_Module;
1054         }
1055 
1056         @Override @DefinedBy(Api.LANGUAGE_MODEL)
1057         public Name getSimpleName() {
1058             return Convert.shortName(name);
1059         }
1060 
1061         @Override @DefinedBy(Api.LANGUAGE_MODEL)
1062         public boolean isOpen() {
1063             return flags.contains(ModuleFlags.OPEN);
1064         }
1065 
1066         @Override @DefinedBy(Api.LANGUAGE_MODEL)
1067         public boolean isUnnamed() {
1068             return name.isEmpty() && owner == null;
1069         }
1070 
1071         @Override
1072         public boolean isDeprecated() {
1073             return hasDeprecatedAnnotation();
1074         }
1075 
1076         public boolean isNoModule() {
1077             return false;
1078         }
1079 
1080         @Override @DefinedBy(Api.LANGUAGE_MODEL)
1081         public ElementKind getKind() {
1082             return ElementKind.MODULE;
1083         }
1084 
1085         @Override @DefinedBy(Api.LANGUAGE_MODEL)
1086         public java.util.List<Directive> getDirectives() {
1087             apiComplete();
1088             completeUsesProvides();
1089             return Collections.unmodifiableList(directives);
1090         }
1091 
1092         public void completeUsesProvides() {
1093             if (usesProvidesCompleter != Completer.NULL_COMPLETER) {
1094                 Completer c = usesProvidesCompleter;
1095                 usesProvidesCompleter = Completer.NULL_COMPLETER;
1096                 c.complete(this);
1097             }
1098         }
1099 
1100         @Override
1101         public ClassSymbol outermostClass() {
1102             return null;
1103         }
1104 
1105         @Override
1106         public String toString() {
1107             // TODO: the following strings should be localized
1108             // Do this with custom anon subtypes in Symtab
1109             String n = (name == null) ? "<unknown>"
1110                     : (name.isEmpty()) ? "<unnamed>"
1111                     : String.valueOf(name);
1112             return n;
1113         }
1114 
1115         @Override @DefinedBy(Api.LANGUAGE_MODEL)
1116         public <R, P> R accept(ElementVisitor<R, P> v, P p) {
1117             return v.visitModule(this, p);
1118         }
1119 
1120         @Override @DefinedBy(Api.LANGUAGE_MODEL)
1121         public List<Symbol> getEnclosedElements() {
1122             List<Symbol> list = List.nil();
1123             for (Symbol sym : enclosedPackages) {
1124                 if (sym.members().anyMatch(m -> m.kind == TYP))
1125                     list = list.prepend(sym);
1126             }
1127             return list;
1128         }
1129 
1130         public void reset() {
1131             this.directives = null;
1132             this.requires = null;
1133             this.exports = null;
1134             this.provides = null;
1135             this.uses = null;
1136             this.visiblePackages = null;
1137         }
1138 
1139     }
1140 
1141     public enum ModuleFlags {
1142         OPEN(0x0020),
1143         SYNTHETIC(0x1000),
1144         MANDATED(0x8000);
1145 
1146         public static int value(Set<ModuleFlags> s) {
1147             int v = 0;
1148             for (ModuleFlags f: s)
1149                 v |= f.value;
1150             return v;
1151         }
1152 
1153         private ModuleFlags(int value) {
1154             this.value = value;
1155         }
1156 
1157         public final int value;
1158     }
1159 
1160     public enum ModuleResolutionFlags {
1161         DO_NOT_RESOLVE_BY_DEFAULT(0x0001),
1162         WARN_DEPRECATED(0x0002),
1163         WARN_DEPRECATED_REMOVAL(0x0004),
1164         WARN_INCUBATING(0x0008);
1165 
1166         public static int value(Set<ModuleResolutionFlags> s) {
1167             int v = 0;
1168             for (ModuleResolutionFlags f: s)
1169                 v |= f.value;
1170             return v;
1171         }
1172 
1173         private ModuleResolutionFlags(int value) {
1174             this.value = value;
1175         }
1176 
1177         public final int value;
1178     }
1179 
1180     /** A class for package symbols
1181      */
1182     public static class PackageSymbol extends TypeSymbol
1183         implements PackageElement {
1184 
1185         public WriteableScope members_field;
1186         public Name fullname;
1187         public ClassSymbol package_info; // see bug 6443073
1188         public ModuleSymbol modle;
1189         // the file containing the documentation comments for the package
1190         public JavaFileObject sourcefile;
1191 
1192         public PackageSymbol(Name name, Type type, Symbol owner) {
1193             super(PCK, 0, name, type, owner);
1194             this.members_field = null;
1195             this.fullname = formFullName(name, owner);
1196         }
1197 
1198         @SuppressWarnings("this-escape")
1199         public PackageSymbol(Name name, Symbol owner) {
1200             this(name, null, owner);
1201             this.type = new PackageType(this);
1202         }
1203 
1204         public String toString() {
1205             return fullname.toString();
1206         }
1207 
1208         @DefinedBy(Api.LANGUAGE_MODEL)
1209         public Name getQualifiedName() {
1210             return fullname;
1211         }
1212 
1213         @DefinedBy(Api.LANGUAGE_MODEL)
1214         public boolean isUnnamed() {
1215             return name.isEmpty() && owner != null;
1216         }
1217 
1218         public WriteableScope members() {
1219             complete();
1220             return members_field;
1221         }
1222 
1223         @Override
1224         public int poolTag() {
1225             return ClassFile.CONSTANT_Package;
1226         }
1227 
1228         public long flags() {
1229             complete();
1230             return flags_field;
1231         }
1232 
1233         @Override
1234         public List<Attribute.Compound> getRawAttributes() {
1235             complete();
1236             if (package_info != null) {
1237                 package_info.complete();
1238                 mergeAttributes();
1239             }
1240             return super.getRawAttributes();
1241         }
1242 
1243         private void mergeAttributes() {
1244             if (metadata == null &&
1245                 package_info.metadata != null) {
1246                 metadata = new SymbolMetadata(this);
1247                 metadata.setAttributes(package_info.metadata);
1248             }
1249         }
1250 
1251         /** A package "exists" if a type or package that exists has
1252          *  been seen within it.
1253          */
1254         public boolean exists() {
1255             return (flags_field & EXISTS) != 0;
1256         }
1257 
1258         @DefinedBy(Api.LANGUAGE_MODEL)
1259         public ElementKind getKind() {
1260             return ElementKind.PACKAGE;
1261         }
1262 
1263         @DefinedBy(Api.LANGUAGE_MODEL)
1264         public Symbol getEnclosingElement() {
1265             return modle != null && !modle.isNoModule() ? modle : null;
1266         }
1267 
1268         @DefinedBy(Api.LANGUAGE_MODEL)
1269         public <R, P> R accept(ElementVisitor<R, P> v, P p) {
1270             return v.visitPackage(this, p);
1271         }
1272 
1273         public <R, P> R accept(Symbol.Visitor<R, P> v, P p) {
1274             return v.visitPackageSymbol(this, p);
1275         }
1276 
1277         /**Resets the Symbol into the state good for next round of annotation processing.*/
1278         public void reset() {
1279             metadata = null;
1280         }
1281 
1282     }
1283 
1284     public static class RootPackageSymbol extends PackageSymbol {
1285         public final MissingInfoHandler missingInfoHandler;
1286         public final boolean allowPrivateInvokeVirtual;
1287 
1288         public RootPackageSymbol(Name name, Symbol owner,
1289                                  MissingInfoHandler missingInfoHandler,
1290                                  boolean allowPrivateInvokeVirtual) {
1291             super(name, owner);
1292             this.missingInfoHandler = missingInfoHandler;
1293             this.allowPrivateInvokeVirtual = allowPrivateInvokeVirtual;
1294         }
1295 
1296     }
1297 
1298     /** A class for class symbols
1299      */
1300     public static class ClassSymbol extends TypeSymbol implements TypeElement {
1301 
1302         /** a scope for all class members; variables, methods and inner classes
1303          *  type parameters are not part of this scope
1304          */
1305         public WriteableScope members_field;
1306 
1307         /** the fully qualified name of the class, i.e. pck.outer.inner.
1308          *  null for anonymous classes
1309          */
1310         public Name fullname;
1311 
1312         /** the fully qualified name of the class after converting to flat
1313          *  representation, i.e. pck.outer$inner,
1314          *  set externally for local and anonymous classes
1315          */
1316         public Name flatname;
1317 
1318         /** the sourcefile where the class came from
1319          */
1320         public JavaFileObject sourcefile;
1321 
1322         /** the classfile from where to load this class
1323          *  this will have extension .class or .java
1324          */
1325         public JavaFileObject classfile;
1326 
1327         /** the list of translated local classes (used for generating
1328          * InnerClasses attribute)
1329          */
1330         public List<ClassSymbol> trans_local;
1331 
1332         /** the annotation metadata attached to this class */
1333         private AnnotationTypeMetadata annotationTypeMetadata;
1334 
1335         /* the list of any of record components, only non empty if the class is a record
1336          * and it has at least one record component
1337          */
1338         private List<RecordComponent> recordComponents = List.nil();
1339 
1340         // sealed classes related fields
1341         /** The classes, or interfaces, permitted to extend this class, or interface
1342          */
1343         private java.util.List<PermittedClassWithPos> permitted;
1344 
1345         public boolean isPermittedExplicit = false;
1346 
1347         private record PermittedClassWithPos(Symbol permittedClass, int pos) {}
1348 
1349         public ClassSymbol(long flags, Name name, Type type, Symbol owner) {
1350             super(TYP, flags, name, type, owner);
1351             this.members_field = null;
1352             this.fullname = formFullName(name, owner);
1353             this.flatname = formFlatName(name, owner);
1354             this.sourcefile = null;
1355             this.classfile = null;
1356             this.annotationTypeMetadata = AnnotationTypeMetadata.notAnAnnotationType();
1357             this.permitted = new ArrayList<>();
1358         }
1359 
1360         public ClassSymbol(long flags, Name name, Symbol owner) {
1361             this(
1362                 flags,
1363                 name,
1364                 new ClassType(Type.noType, null, null, List.nil()),
1365                 owner);
1366             this.type.tsym = this;
1367         }
1368 
1369         public void addPermittedSubclass(ClassSymbol csym, int pos) {
1370             Assert.check(!isPermittedExplicit);
1371             // we need to insert at the right pos
1372             PermittedClassWithPos element = new PermittedClassWithPos(csym, pos);
1373             int index = Collections.binarySearch(permitted, element, java.util.Comparator.comparing(PermittedClassWithPos::pos));
1374             if (index < 0) {
1375                 index = -index - 1;
1376                 permitted.add(index, element);
1377             }
1378         }
1379 
1380         public boolean isPermittedSubclass(Symbol csym) {
1381             for (PermittedClassWithPos permittedClassWithPos : permitted) {
1382                 if (permittedClassWithPos.permittedClass.equals(csym)) {
1383                     return true;
1384                 }
1385             }
1386             return false;
1387         }
1388 
1389         public void clearPermittedSubclasses() {
1390             permitted.clear();
1391         }
1392 
1393         public void setPermittedSubclasses(List<Symbol> permittedSubs) {
1394             permitted.clear();
1395             for (Symbol csym : permittedSubs) {
1396                 permitted.add(new PermittedClassWithPos(csym, 0));
1397             }
1398         }
1399 
1400         /** The Java source which this symbol represents.
1401          */
1402         public String toString() {
1403             return className();
1404         }
1405 
1406         public long flags() {
1407             complete();
1408             return flags_field;
1409         }
1410 
1411         public WriteableScope members() {
1412             complete();
1413             return members_field;
1414         }
1415 
1416         @Override
1417         public List<Attribute.Compound> getRawAttributes() {
1418             complete();
1419             return super.getRawAttributes();
1420         }
1421 
1422         @Override
1423         public List<Attribute.TypeCompound> getRawTypeAttributes() {
1424             complete();
1425             return super.getRawTypeAttributes();
1426         }
1427 
1428         public Type erasure(Types types) {
1429             if (erasure_field == null)
1430                 erasure_field = new ClassType(types.erasure(type.getEnclosingType()),
1431                                               List.nil(), this,
1432                                               type.getMetadata());
1433             return erasure_field;
1434         }
1435 
1436         public String className() {
1437             if (name.isEmpty())
1438                 return
1439                     Log.getLocalizedString("anonymous.class", flatname);
1440             else
1441                 return fullname.toString();
1442         }
1443 
1444          @Override @DefinedBy(Api.LANGUAGE_MODEL)
1445          public Name getQualifiedName() {
1446              return fullname;
1447          }
1448 
1449          @Override @DefinedBy(Api.LANGUAGE_MODEL)
1450          public Name getSimpleName() {
1451              return name;
1452          }
1453 
1454         @Override @DefinedBy(Api.LANGUAGE_MODEL)
1455         public List<Symbol> getEnclosedElements() {
1456             List<Symbol> result = super.getEnclosedElements();
1457             if (!recordComponents.isEmpty()) {
1458                 List<RecordComponent> reversed = recordComponents.reverse();
1459                 for (RecordComponent rc : reversed) {
1460                     result = result.prepend(rc);
1461                 }
1462             }
1463             return result;
1464         }
1465 
1466         public Name flatName() {
1467             return flatname;
1468         }
1469 
1470         public boolean isSubClass(Symbol base, Types types) {
1471             if (this == base) {
1472                 return true;
1473             } else if ((base.flags() & INTERFACE) != 0) {
1474                 for (Type t = type; t.hasTag(CLASS); t = types.supertype(t))
1475                     for (List<Type> is = types.interfaces(t);
1476                          is.nonEmpty();
1477                          is = is.tail)
1478                         if (is.head.tsym.isSubClass(base, types)) return true;
1479             } else {
1480                 for (Type t = type; t.hasTag(CLASS); t = types.supertype(t))
1481                     if (t.tsym == base) return true;
1482             }
1483             return false;
1484         }
1485 
1486         /** Complete the elaboration of this symbol's definition.
1487          */
1488         public void complete() throws CompletionFailure {
1489             Completer origCompleter = completer;
1490             try {
1491                 super.complete();
1492             } catch (CompletionFailure ex) {
1493                 ex.dcfh.classSymbolCompleteFailed(this, origCompleter);
1494                 // quiet error recovery
1495                 flags_field |= (PUBLIC|STATIC);
1496                 this.type = new ErrorType(this, Type.noType);
1497                 throw ex;
1498             }
1499         }
1500 
1501         @DefinedBy(Api.LANGUAGE_MODEL)
1502         public List<Type> getInterfaces() {
1503             apiComplete();
1504             if (type instanceof ClassType classType) {
1505                 if (classType.interfaces_field == null) // FIXME: shouldn't be null
1506                     classType.interfaces_field = List.nil();
1507                 if (classType.all_interfaces_field != null)
1508                     return Type.getModelTypes(classType.all_interfaces_field);
1509                 return classType.interfaces_field;
1510             } else {
1511                 return List.nil();
1512             }
1513         }
1514 
1515         @DefinedBy(Api.LANGUAGE_MODEL)
1516         public Type getSuperclass() {
1517             apiComplete();
1518             if (type instanceof ClassType classType) {
1519                 if (classType.supertype_field == null) // FIXME: shouldn't be null
1520                     classType.supertype_field = Type.noType;
1521                 // An interface has no superclass; its supertype is Object.
1522                 return classType.isInterface()
1523                     ? Type.noType
1524                     : classType.supertype_field.getModelType();
1525             } else {
1526                 return Type.noType;
1527             }
1528         }
1529 
1530         /**
1531          * Returns the next class to search for inherited annotations or {@code null}
1532          * if the next class can't be found.
1533          */
1534         private ClassSymbol getSuperClassToSearchForAnnotations() {
1535 
1536             Type sup = getSuperclass();
1537 
1538             if (!sup.hasTag(CLASS) || sup.isErroneous())
1539                 return null;
1540 
1541             return (ClassSymbol) sup.tsym;
1542         }
1543 
1544 
1545         @Override
1546         protected <A extends Annotation> A[] getInheritedAnnotations(Class<A> annoType) {
1547 
1548             ClassSymbol sup = getSuperClassToSearchForAnnotations();
1549 
1550             return sup == null ? super.getInheritedAnnotations(annoType)
1551                                : sup.getAnnotationsByType(annoType);
1552         }
1553 
1554 
1555         @DefinedBy(Api.LANGUAGE_MODEL)
1556         public ElementKind getKind() {
1557             apiComplete();
1558             long flags = flags();
1559             if ((flags & ANNOTATION) != 0)
1560                 return ElementKind.ANNOTATION_TYPE;
1561             else if ((flags & INTERFACE) != 0)
1562                 return ElementKind.INTERFACE;
1563             else if ((flags & ENUM) != 0)
1564                 return ElementKind.ENUM;
1565             else if ((flags & RECORD) != 0)
1566                 return ElementKind.RECORD;
1567             else
1568                 return ElementKind.CLASS;
1569         }
1570 
1571         @Override @DefinedBy(Api.LANGUAGE_MODEL)
1572         public Set<Modifier> getModifiers() {
1573             apiComplete();
1574             long flags = flags();
1575             return Flags.asModifierSet(flags & ~DEFAULT);
1576         }
1577 
1578         public RecordComponent getRecordComponent(VarSymbol field) {
1579             for (RecordComponent rc : recordComponents) {
1580                 if (rc.name == field.name) {
1581                     return rc;
1582                 }
1583             }
1584             return null;
1585         }
1586 
1587         /* creates a record component if non is related to the given variable and recreates a brand new one
1588          * in other case
1589          */
1590         public RecordComponent createRecordComponent(RecordComponent existing, JCVariableDecl rcDecl, VarSymbol varSym) {
1591             RecordComponent rc = null;
1592             if (existing != null && !recordComponents.isEmpty()) {
1593                 ListBuffer<RecordComponent> newRComps = new ListBuffer<>();
1594                 for (RecordComponent rcomp : recordComponents) {
1595                     if (existing == rcomp) {
1596                         newRComps.add(rc = new RecordComponent(varSym, existing.ast, existing.isVarargs));
1597                     } else {
1598                         newRComps.add(rcomp);
1599                     }
1600                 }
1601                 recordComponents = newRComps.toList();
1602             } else {
1603                 // Didn't find the record component: create one.
1604                 recordComponents = recordComponents.append(rc = new RecordComponent(varSym, rcDecl));
1605             }
1606             return rc;
1607         }
1608 
1609         @Override @DefinedBy(Api.LANGUAGE_MODEL)
1610         public List<? extends RecordComponent> getRecordComponents() {
1611             return recordComponents;
1612         }
1613 
1614         public void setRecordComponents(List<RecordComponent> recordComponents) {
1615             this.recordComponents = recordComponents;
1616         }
1617 
1618         @DefinedBy(Api.LANGUAGE_MODEL)
1619         public NestingKind getNestingKind() {
1620             apiComplete();
1621             if (owner.kind == PCK) // Handles implicitly declared classes as well
1622                 return NestingKind.TOP_LEVEL;
1623             else if (name.isEmpty())
1624                 return NestingKind.ANONYMOUS;
1625             else if (owner.kind == MTH)
1626                 return NestingKind.LOCAL;
1627             else
1628                 return NestingKind.MEMBER;
1629         }
1630 
1631         @Override
1632         protected <A extends Annotation> Attribute.Compound getAttribute(final Class<A> annoType) {
1633 
1634             Attribute.Compound attrib = super.getAttribute(annoType);
1635 
1636             boolean inherited = annoType.isAnnotationPresent(Inherited.class);
1637             if (attrib != null || !inherited)
1638                 return attrib;
1639 
1640             // Search supertypes
1641             ClassSymbol superType = getSuperClassToSearchForAnnotations();
1642             return superType == null ? null
1643                                      : superType.getAttribute(annoType);
1644         }
1645 
1646         @DefinedBy(Api.LANGUAGE_MODEL)
1647         public <R, P> R accept(ElementVisitor<R, P> v, P p) {
1648             return v.visitType(this, p);
1649         }
1650 
1651         public <R, P> R accept(Symbol.Visitor<R, P> v, P p) {
1652             return v.visitClassSymbol(this, p);
1653         }
1654 
1655         public void markAbstractIfNeeded(Types types) {
1656             if (types.enter.getEnv(this) != null &&
1657                 (flags() & ENUM) != 0 && types.supertype(type).tsym == types.syms.enumSym &&
1658                 (flags() & (FINAL | ABSTRACT)) == 0) {
1659                 if (types.firstUnimplementedAbstract(this) != null)
1660                     // add the ABSTRACT flag to an enum
1661                     flags_field |= ABSTRACT;
1662             }
1663         }
1664 
1665         /**Resets the Symbol into the state good for next round of annotation processing.*/
1666         public void reset() {
1667             kind = TYP;
1668             erasure_field = null;
1669             members_field = null;
1670             flags_field = 0;
1671             if (type instanceof ClassType classType) {
1672                 classType.setEnclosingType(Type.noType);
1673                 classType.rank_field = -1;
1674                 classType.typarams_field = null;
1675                 classType.allparams_field = null;
1676                 classType.supertype_field = null;
1677                 classType.interfaces_field = null;
1678                 classType.all_interfaces_field = null;
1679             }
1680             clearAnnotationMetadata();
1681         }
1682 
1683         public void clearAnnotationMetadata() {
1684             metadata = null;
1685             annotationTypeMetadata = AnnotationTypeMetadata.notAnAnnotationType();
1686         }
1687 
1688         @Override
1689         public AnnotationTypeMetadata getAnnotationTypeMetadata() {
1690             return annotationTypeMetadata;
1691         }
1692 
1693         @Override
1694         public boolean isAnnotationType() {
1695             return (flags_field & Flags.ANNOTATION) != 0;
1696         }
1697 
1698         public void setAnnotationTypeMetadata(AnnotationTypeMetadata a) {
1699             Assert.checkNonNull(a);
1700             Assert.check(!annotationTypeMetadata.isMetadataForAnnotationType());
1701             this.annotationTypeMetadata = a;
1702         }
1703 
1704         public boolean isRecord() {
1705             return (flags_field & RECORD) != 0;
1706         }
1707 
1708         @DefinedBy(Api.LANGUAGE_MODEL)
1709         public List<Type> getPermittedSubclasses() {
1710             return permitted.stream().map(s -> s.permittedClass().type).collect(List.collector());
1711         }
1712     }
1713 
1714 
1715     /** A class for variable symbols
1716      */
1717     public static class VarSymbol extends Symbol implements VariableElement {
1718 
1719         /** The variable's declaration position.
1720          */
1721         public int pos = Position.NOPOS;
1722 
1723         /** The variable's address. Used for different purposes during
1724          *  flow analysis, translation and code generation.
1725          *  Flow analysis:
1726          *    If this is a blank final or local variable, its sequence number.
1727          *  Translation:
1728          *    If this is a private field, its access number.
1729          *  Code generation:
1730          *    If this is a local variable, its logical slot number.
1731          */
1732         public int adr = -1;
1733 
1734         /** Construct a variable symbol, given its flags, name, type and owner.
1735          */
1736         public VarSymbol(long flags, Name name, Type type, Symbol owner) {
1737             super(VAR, flags, name, type, owner);
1738         }
1739 
1740         @Override
1741         public int poolTag() {
1742             return ClassFile.CONSTANT_Fieldref;
1743         }
1744 
1745         public MethodHandleSymbol asMethodHandle(boolean getter) {
1746             return new MethodHandleSymbol(this, getter);
1747         }
1748 
1749         /** Clone this symbol with new owner.
1750          */
1751         public VarSymbol clone(Symbol newOwner) {
1752             VarSymbol v = new VarSymbol(flags_field, name, type, newOwner) {
1753                 @Override
1754                 public Symbol baseSymbol() {
1755                     return VarSymbol.this;
1756                 }
1757 
1758                 @Override
1759                 public Object poolKey(Types types) {
1760                     return new Pair<>(newOwner, baseSymbol());
1761                 }
1762             };
1763             v.pos = pos;
1764             v.adr = adr;
1765             v.data = data;
1766 //          System.out.println("clone " + v + " in " + newOwner);//DEBUG
1767             return v;
1768         }
1769 
1770         public String toString() {
1771             return name.toString();
1772         }
1773 
1774         public Symbol asMemberOf(Type site, Types types) {
1775             return new VarSymbol(flags_field, name, types.memberType(site, this), owner);
1776         }
1777 
1778         @DefinedBy(Api.LANGUAGE_MODEL)
1779         public ElementKind getKind() {
1780             long flags = flags();
1781             if ((flags & PARAMETER) != 0) {
1782                 if (isExceptionParameter())
1783                     return ElementKind.EXCEPTION_PARAMETER;
1784                 else
1785                     return ElementKind.PARAMETER;
1786             } else if ((flags & ENUM) != 0) {
1787                 return ElementKind.ENUM_CONSTANT;
1788             } else if (owner.kind == TYP || owner.kind == ERR) {
1789                 return ElementKind.FIELD;
1790             } else if (isResourceVariable()) {
1791                 return ElementKind.RESOURCE_VARIABLE;
1792             } else if ((flags & MATCH_BINDING) != 0) {
1793                 ElementKind kind = ElementKind.BINDING_VARIABLE;
1794                 return kind;
1795             } else {
1796                 return ElementKind.LOCAL_VARIABLE;
1797             }
1798         }
1799 
1800         @DefinedBy(Api.LANGUAGE_MODEL)
1801         public <R, P> R accept(ElementVisitor<R, P> v, P p) {
1802             return v.visitVariable(this, p);
1803         }
1804 
1805         @DefinedBy(Api.LANGUAGE_MODEL)
1806         public Object getConstantValue() { // Mirror API
1807             return Constants.decode(getConstValue(), type);
1808         }
1809 
1810         public void setLazyConstValue(final Env<AttrContext> env,
1811                                       final Env<AttrContext> enclosingEnv,
1812                                       final Attr attr,
1813                                       final JCVariableDecl variable)
1814         {
1815             setData((Callable<Object>)() -> attr.attribLazyConstantValue(env, enclosingEnv, variable, type));
1816         }
1817 
1818         /**
1819          * The variable's constant value, if this is a constant.
1820          * Before the constant value is evaluated, it points to an
1821          * initializer environment.  If this is not a constant, it can
1822          * be used for other stuff.
1823          */
1824         private Object data;
1825 
1826         public boolean isExceptionParameter() {
1827             return data == ElementKind.EXCEPTION_PARAMETER;
1828         }
1829 
1830         public boolean isResourceVariable() {
1831             return data == ElementKind.RESOURCE_VARIABLE;
1832         }
1833 
1834         public Object getConstValue() {
1835             // TODO: Consider if getConstValue and getConstantValue can be collapsed
1836             if (data == ElementKind.EXCEPTION_PARAMETER ||
1837                 data == ElementKind.RESOURCE_VARIABLE) {
1838                 return null;
1839             } else if (data instanceof Callable<?> callableData) {
1840                 // In this case, this is a final variable, with an as
1841                 // yet unevaluated initializer.
1842                 data = null; // to make sure we don't evaluate this twice.
1843                 try {
1844                     data = callableData.call();
1845                 } catch (Exception ex) {
1846                     throw new AssertionError(ex);
1847                 }
1848             }
1849             return data;
1850         }
1851 
1852         public void setData(Object data) {
1853             Assert.check(!(data instanceof Env<?>), this);
1854             this.data = data;
1855         }
1856 
1857         public <R, P> R accept(Symbol.Visitor<R, P> v, P p) {
1858             return v.visitVarSymbol(this, p);
1859         }
1860 
1861         public boolean isUnnamedVariable() {
1862             return name.isEmpty();
1863         }
1864     }
1865 
1866     public static class RecordComponent extends VarSymbol implements RecordComponentElement {
1867         public MethodSymbol accessor;
1868         public JCTree.JCMethodDecl accessorMeth;
1869 
1870         /* if the user happens to erroneously declare two components with the same name, we need a way to differentiate
1871          * them, the code will fail anyway but we need to keep the information for better error recovery
1872          */
1873         private final int pos;
1874 
1875         private final boolean isVarargs;
1876 
1877         private JCVariableDecl ast;
1878 
1879         /**
1880          * Construct a record component, given its flags, name, type and owner.
1881          */
1882         public RecordComponent(Name name, Type type, Symbol owner) {
1883             super(PUBLIC, name, type, owner);
1884             pos = -1;
1885             ast = null;
1886             isVarargs = false;
1887         }
1888 
1889         public RecordComponent(VarSymbol field, JCVariableDecl ast) {
1890             this(field, ast, field.type.hasTag(TypeTag.ARRAY) && ((ArrayType)field.type).isVarargs());
1891         }
1892 
1893         public RecordComponent(VarSymbol field, JCVariableDecl ast, boolean isVarargs) {
1894             super(PUBLIC, field.name, field.type, field.owner);
1895             this.ast = ast;
1896             this.pos = field.pos;
1897             /* it is better to store the original information for this one, instead of relying
1898              * on the info in the type of the symbol. This is because on the presence of APs
1899              * the symbol will be blown out and we won't be able to know if the original
1900              * record component was declared varargs or not.
1901              */
1902             this.isVarargs = isVarargs;
1903         }
1904 
1905         public List<JCAnnotation> getOriginalAnnos() { return this.ast == null ? List.nil() : this.ast.mods.annotations; }
1906 
1907         public JCVariableDecl declarationFor() { return this.ast; }
1908 
1909         public boolean isVarargs() {
1910             return isVarargs;
1911         }
1912 
1913         @Override @DefinedBy(Api.LANGUAGE_MODEL)
1914         public ElementKind getKind() {
1915             return ElementKind.RECORD_COMPONENT;
1916         }
1917 
1918         @Override @DefinedBy(Api.LANGUAGE_MODEL)
1919         public ExecutableElement getAccessor() {
1920             return accessor;
1921         }
1922 
1923         @Override @DefinedBy(Api.LANGUAGE_MODEL)
1924         public <R, P> R accept(ElementVisitor<R, P> v, P p) {
1925             return v.visitRecordComponent(this, p);
1926         }
1927     }
1928 
1929     public static class ParamSymbol extends VarSymbol {
1930         public ParamSymbol(long flags, Name name, Type type, Symbol owner) {
1931             super(flags, name, type, owner);
1932         }
1933 
1934         @Override
1935         public Name getSimpleName() {
1936             if ((flags_field & NAME_FILLED) == 0) {
1937                 flags_field |= NAME_FILLED;
1938                 Symbol rootPack = this;
1939                 while (rootPack != null && !(rootPack instanceof RootPackageSymbol)) {
1940                     rootPack = rootPack.owner;
1941                 }
1942                 if (rootPack != null) {
1943                     Name inferredName =
1944                             ((RootPackageSymbol) rootPack).missingInfoHandler.getParameterName(this);
1945                     if (inferredName != null) {
1946                         this.name = inferredName;
1947                     }
1948                 }
1949             }
1950             return super.getSimpleName();
1951         }
1952 
1953     }
1954 
1955     public static class BindingSymbol extends VarSymbol {
1956 
1957         public BindingSymbol(long flags, Name name, Type type, Symbol owner) {
1958             super(flags | Flags.HASINIT | Flags.MATCH_BINDING, name, type, owner);
1959         }
1960 
1961         public boolean isAliasFor(BindingSymbol b) {
1962             return aliases().containsAll(b.aliases());
1963         }
1964 
1965         List<BindingSymbol> aliases() {
1966             return List.of(this);
1967         }
1968 
1969         public void preserveBinding() {
1970             flags_field |= Flags.MATCH_BINDING_TO_OUTER;
1971         }
1972 
1973         public boolean isPreserved() {
1974             return (flags_field & Flags.MATCH_BINDING_TO_OUTER) != 0;
1975         }
1976     }
1977 
1978     /** A class for method symbols.
1979      */
1980     public static class MethodSymbol extends Symbol implements ExecutableElement {
1981 
1982         /** The code of the method. */
1983         public Code code = null;
1984 
1985         /** The extra (synthetic/mandated) parameters of the method. */
1986         public List<VarSymbol> extraParams = List.nil();
1987 
1988         /** The captured local variables in an anonymous class */
1989         public List<VarSymbol> capturedLocals = List.nil();
1990 
1991         /** The parameters of the method. */
1992         public List<VarSymbol> params = null;
1993 
1994         /** For an annotation type element, its default value if any.
1995          *  The value is null if none appeared in the method
1996          *  declaration.
1997          */
1998         public Attribute defaultValue = null;
1999 
2000         /** Construct a method symbol, given its flags, name, type and owner.
2001          */
2002         public MethodSymbol(long flags, Name name, Type type, Symbol owner) {
2003             super(MTH, flags, name, type, owner);
2004             if (owner.type.hasTag(TYPEVAR)) Assert.error(owner + "." + name);
2005         }
2006 
2007         /** Clone this symbol with new owner.
2008          */
2009         public MethodSymbol clone(Symbol newOwner) {
2010             MethodSymbol m = new MethodSymbol(flags_field, name, type, newOwner) {
2011                 @Override
2012                 public Symbol baseSymbol() {
2013                     return MethodSymbol.this;
2014                 }
2015 
2016                 @Override
2017                 public Object poolKey(Types types) {
2018                     return new Pair<>(newOwner, baseSymbol());
2019                 }
2020             };
2021             m.code = code;
2022             return m;
2023         }
2024 
2025         @Override @DefinedBy(Api.LANGUAGE_MODEL)
2026         public Set<Modifier> getModifiers() {
2027             // just in case the method is restricted but that is not a modifier
2028             long flags = flags() & ~RESTRICTED;
2029             return Flags.asModifierSet((flags & DEFAULT) != 0 ? flags & ~ABSTRACT : flags);
2030         }
2031 
2032         /** The Java source which this symbol represents.
2033          */
2034         public String toString() {
2035             if ((flags() & BLOCK) != 0) {
2036                 return owner.name.toString();
2037             } else {
2038                 String s = (name == name.table.names.init)
2039                     ? owner.name.toString()
2040                     : name.toString();
2041                 if (type != null) {
2042                     if (type.hasTag(FORALL))
2043                         s = "<" + ((ForAll)type).getTypeArguments() + ">" + s;
2044                     s += "(" + type.argtypes((flags() & VARARGS) != 0) + ")";
2045                 }
2046                 return s;
2047             }
2048         }
2049 
2050         @Override
2051         public int poolTag() {
2052             return owner.isInterface() ?
2053                     ClassFile.CONSTANT_InterfaceMethodref : ClassFile.CONSTANT_Methodref;
2054         }
2055 
2056         public boolean isHandle() {
2057             return false;
2058         }
2059 
2060 
2061         public MethodHandleSymbol asHandle() {
2062             return new MethodHandleSymbol(this);
2063         }
2064 
2065         /** find a symbol that this (proxy method) symbol implements.
2066          *  @param    c       The class whose members are searched for
2067          *                    implementations
2068          */
2069         public Symbol implemented(TypeSymbol c, Types types) {
2070             Symbol impl = null;
2071             for (List<Type> is = types.interfaces(c.type);
2072                  impl == null && is.nonEmpty();
2073                  is = is.tail) {
2074                 TypeSymbol i = is.head.tsym;
2075                 impl = implementedIn(i, types);
2076                 if (impl == null)
2077                     impl = implemented(i, types);
2078             }
2079             return impl;
2080         }
2081 
2082         public Symbol implementedIn(TypeSymbol c, Types types) {
2083             Symbol impl = null;
2084             for (Symbol sym : c.members().getSymbolsByName(name)) {
2085                 if (this.overrides(sym, (TypeSymbol)owner, types, true) &&
2086                     // FIXME: I suspect the following requires a
2087                     // subst() for a parametric return type.
2088                     types.isSameType(type.getReturnType(),
2089                                      types.memberType(owner.type, sym).getReturnType())) {
2090                     impl = sym;
2091                 }
2092             }
2093             return impl;
2094         }
2095 
2096         /** Will the erasure of this method be considered by the VM to
2097          *  override the erasure of the other when seen from class `origin'?
2098          */
2099         public boolean binaryOverrides(Symbol _other, TypeSymbol origin, Types types) {
2100             if (isConstructor() || _other.kind != MTH) return false;
2101 
2102             if (this == _other) return true;
2103             MethodSymbol other = (MethodSymbol)_other;
2104 
2105             // check for a direct implementation
2106             if (other.isOverridableIn((TypeSymbol)owner) &&
2107                 types.asSuper(owner.type, other.owner) != null &&
2108                 types.isSameType(erasure(types), other.erasure(types)))
2109                 return true;
2110 
2111             // check for an inherited implementation
2112             return
2113                 (flags() & ABSTRACT) == 0 &&
2114                 other.isOverridableIn(origin) &&
2115                 this.isMemberOf(origin, types) &&
2116                 types.isSameType(erasure(types), other.erasure(types));
2117         }
2118 
2119         /** The implementation of this (abstract) symbol in class origin,
2120          *  from the VM's point of view, null if method does not have an
2121          *  implementation in class.
2122          *  @param origin   The class of which the implementation is a member.
2123          */
2124         public MethodSymbol binaryImplementation(ClassSymbol origin, Types types) {
2125             for (TypeSymbol c = origin; c != null; c = types.supertype(c.type).tsym) {
2126                 for (Symbol sym : c.members().getSymbolsByName(name)) {
2127                     if (sym.kind == MTH &&
2128                         ((MethodSymbol)sym).binaryOverrides(this, origin, types))
2129                         return (MethodSymbol)sym;
2130                 }
2131             }
2132             return null;
2133         }
2134 
2135         /** Does this symbol override `other' symbol, when both are seen as
2136          *  members of class `origin'?  It is assumed that _other is a member
2137          *  of origin.
2138          *
2139          *  It is assumed that both symbols have the same name.  The static
2140          *  modifier is ignored for this test.
2141          *
2142          *  A quirk in the works is that if the receiver is a method symbol for
2143          *  an inherited abstract method we answer false summarily all else being
2144          *  immaterial. Abstract "own" methods (i.e `this' is a direct member of
2145          *  origin) don't get rejected as summarily and are put to test against the
2146          *  suitable criteria.
2147          *
2148          *  See JLS 8.4.8.1 (without transitivity) and 8.4.8.4
2149          */
2150         public boolean overrides(Symbol _other, TypeSymbol origin, Types types, boolean checkResult) {
2151             return overrides(_other, origin, types, checkResult, true);
2152         }
2153 
2154         /** Does this symbol override `other' symbol, when both are seen as
2155          *  members of class `origin'?  It is assumed that _other is a member
2156          *  of origin.
2157          *
2158          *  Caveat: If `this' is an abstract inherited member of origin, it is
2159          *  deemed to override `other' only when `requireConcreteIfInherited'
2160          *  is false.
2161          *
2162          *  It is assumed that both symbols have the same name.  The static
2163          *  modifier is ignored for this test.
2164          *
2165          *  See JLS 8.4.8.1 (without transitivity) and 8.4.8.4
2166          */
2167         public boolean overrides(Symbol _other, TypeSymbol origin, Types types, boolean checkResult,
2168                                             boolean requireConcreteIfInherited) {
2169             if (isConstructor() || _other.kind != MTH) return false;
2170 
2171             if (this == _other) return true;
2172             MethodSymbol other = (MethodSymbol)_other;
2173 
2174             // check for a direct implementation
2175             if (other.isOverridableIn((TypeSymbol)owner) &&
2176                 types.asSuper(owner.type, other.owner) != null) {
2177                 Type mt = types.memberType(owner.type, this);
2178                 Type ot = types.memberType(owner.type, other);
2179                 if (types.isSubSignature(mt, ot)) {
2180                     if (!checkResult)
2181                         return true;
2182                     if (types.returnTypeSubstitutable(mt, ot))
2183                         return true;
2184                 }
2185             }
2186 
2187             // check for an inherited implementation
2188             if (((flags() & ABSTRACT) != 0 && requireConcreteIfInherited) ||
2189                     ((other.flags() & ABSTRACT) == 0 && (other.flags() & DEFAULT) == 0) ||
2190                     !other.isOverridableIn(origin) ||
2191                     !this.isMemberOf(origin, types))
2192                 return false;
2193 
2194             // assert types.asSuper(origin.type, other.owner) != null;
2195             Type mt = types.memberType(origin.type, this);
2196             Type ot = types.memberType(origin.type, other);
2197             return
2198                 types.isSubSignature(mt, ot) &&
2199                 (!checkResult || types.resultSubtype(mt, ot, types.noWarnings));
2200         }
2201 
2202         private boolean isOverridableIn(TypeSymbol origin) {
2203             // JLS 8.4.8.1
2204             switch ((int)(flags_field & Flags.AccessFlags)) {
2205             case Flags.PRIVATE:
2206                 return false;
2207             case Flags.PUBLIC:
2208                 return !this.owner.isInterface() ||
2209                         (flags_field & STATIC) == 0;
2210             case Flags.PROTECTED:
2211                 return (origin.flags() & INTERFACE) == 0;
2212             case 0:
2213                 // for package private: can only override in the same
2214                 // package
2215                 return
2216                     this.packge() == origin.packge() &&
2217                     (origin.flags() & INTERFACE) == 0;
2218             default:
2219                 return false;
2220             }
2221         }
2222 
2223         @Override
2224         public boolean isInheritedIn(Symbol clazz, Types types) {
2225             switch ((int)(flags_field & Flags.AccessFlags)) {
2226                 case PUBLIC:
2227                     return !this.owner.isInterface() ||
2228                             clazz == owner ||
2229                             (flags_field & STATIC) == 0;
2230                 default:
2231                     return super.isInheritedIn(clazz, types);
2232             }
2233         }
2234 
2235         public boolean isLambdaMethod() {
2236             return (flags() & LAMBDA_METHOD) == LAMBDA_METHOD;
2237         }
2238 
2239         /** override this method to point to the original enclosing method if this method symbol represents a synthetic
2240          *  lambda method
2241          */
2242         public MethodSymbol originalEnclosingMethod() {
2243             return this;
2244         }
2245 
2246         /** The implementation of this (abstract) symbol in class origin;
2247          *  null if none exists. Synthetic methods are not considered
2248          *  as possible implementations.
2249          */
2250         public MethodSymbol implementation(TypeSymbol origin, Types types, boolean checkResult) {
2251             return implementation(origin, types, checkResult, implementation_filter);
2252         }
2253         // where
2254             public static final Predicate<Symbol> implementation_filter = s ->
2255                     s.kind == MTH && (s.flags() & SYNTHETIC) == 0;
2256 
2257         public MethodSymbol implementation(TypeSymbol origin, Types types, boolean checkResult, Predicate<Symbol> implFilter) {
2258             MethodSymbol res = types.implementation(this, origin, checkResult, implFilter);
2259             if (res != null)
2260                 return res;
2261             // if origin is derived from a raw type, we might have missed
2262             // an implementation because we do not know enough about instantiations.
2263             // in this case continue with the supertype as origin.
2264             if (types.isDerivedRaw(origin.type) && !origin.isInterface())
2265                 return implementation(types.supertype(origin.type).tsym, types, checkResult);
2266             else
2267                 return null;
2268         }
2269 
2270         public List<VarSymbol> params() {
2271             owner.complete();
2272             if (params == null) {
2273                 ListBuffer<VarSymbol> newParams = new ListBuffer<>();
2274                 int i = 0;
2275                 for (Type t : type.getParameterTypes()) {
2276                     Name paramName = name.table.fromString("arg" + i);
2277                     VarSymbol param = new VarSymbol(PARAMETER, paramName, t, this);
2278                     newParams.append(param);
2279                     i++;
2280                 }
2281                 params = newParams.toList();
2282             }
2283             Assert.checkNonNull(params);
2284             return params;
2285         }
2286 
2287         public Symbol asMemberOf(Type site, Types types) {
2288             return new MethodSymbol(flags_field, name, types.memberType(site, this), owner);
2289         }
2290 
2291         @DefinedBy(Api.LANGUAGE_MODEL)
2292         public ElementKind getKind() {
2293             if (name == name.table.names.init)
2294                 return ElementKind.CONSTRUCTOR;
2295             else if (name == name.table.names.clinit)
2296                 return ElementKind.STATIC_INIT;
2297             else if ((flags() & BLOCK) != 0)
2298                 return isStatic() ? ElementKind.STATIC_INIT : ElementKind.INSTANCE_INIT;
2299             else
2300                 return ElementKind.METHOD;
2301         }
2302 
2303         public boolean isStaticOrInstanceInit() {
2304             return getKind() == ElementKind.STATIC_INIT ||
2305                     getKind() == ElementKind.INSTANCE_INIT;
2306         }
2307 
2308         @DefinedBy(Api.LANGUAGE_MODEL)
2309         public Attribute getDefaultValue() {
2310             return defaultValue;
2311         }
2312 
2313         @DefinedBy(Api.LANGUAGE_MODEL)
2314         public List<VarSymbol> getParameters() {
2315             return params();
2316         }
2317 
2318         @DefinedBy(Api.LANGUAGE_MODEL)
2319         public boolean isVarArgs() {
2320             return (flags() & VARARGS) != 0;
2321         }
2322 
2323         @DefinedBy(Api.LANGUAGE_MODEL)
2324         public boolean isDefault() {
2325             return (flags() & DEFAULT) != 0;
2326         }
2327 
2328         @DefinedBy(Api.LANGUAGE_MODEL)
2329         public <R, P> R accept(ElementVisitor<R, P> v, P p) {
2330             return v.visitExecutable(this, p);
2331         }
2332 
2333         public <R, P> R accept(Symbol.Visitor<R, P> v, P p) {
2334             return v.visitMethodSymbol(this, p);
2335         }
2336 
2337         @DefinedBy(Api.LANGUAGE_MODEL)
2338         public Type getReceiverType() {
2339             return asType().getReceiverType();
2340         }
2341 
2342         public Type implicitReceiverType() {
2343             ClassSymbol enclosingClass = enclClass();
2344             if (enclosingClass == null) {
2345                 return null;
2346             }
2347             Type enclosingType = enclosingClass.type;
2348             if (isConstructor()) {
2349                 return enclosingType.getEnclosingType();
2350             }
2351             if (!isStatic()) {
2352                 return enclosingType;
2353             }
2354             return null;
2355         }
2356 
2357         @DefinedBy(Api.LANGUAGE_MODEL)
2358         public Type getReturnType() {
2359             return asType().getReturnType();
2360         }
2361 
2362         @DefinedBy(Api.LANGUAGE_MODEL)
2363         public List<Type> getThrownTypes() {
2364             return asType().getThrownTypes();
2365         }
2366     }
2367 
2368     /** A class for invokedynamic method calls.
2369      */
2370     public static class DynamicMethodSymbol extends MethodSymbol implements Dynamic {
2371 
2372         public LoadableConstant[] staticArgs;
2373         public MethodHandleSymbol bsm;
2374 
2375         public DynamicMethodSymbol(Name name, Symbol owner, MethodHandleSymbol bsm, Type type, LoadableConstant[] staticArgs) {
2376             super(0, name, type, owner);
2377             this.bsm = bsm;
2378             this.staticArgs = staticArgs;
2379         }
2380 
2381         @Override
2382         public Name name() {
2383             return name;
2384         }
2385 
2386         @Override
2387         public boolean isDynamic() {
2388             return true;
2389         }
2390 
2391         @Override
2392         public LoadableConstant[] staticArgs() {
2393             return staticArgs;
2394         }
2395 
2396         @Override
2397         public MethodHandleSymbol bootstrapMethod() {
2398             return bsm;
2399         }
2400 
2401         @Override
2402         public int poolTag() {
2403             return ClassFile.CONSTANT_InvokeDynamic;
2404         }
2405 
2406         @Override
2407         public Type dynamicType() {
2408             return type;
2409         }
2410     }
2411 
2412     /** A class for condy.
2413      */
2414     public static class DynamicVarSymbol extends VarSymbol implements Dynamic, LoadableConstant {
2415         public LoadableConstant[] staticArgs;
2416         public MethodHandleSymbol bsm;
2417 
2418         public DynamicVarSymbol(Name name, Symbol owner, MethodHandleSymbol bsm, Type type, LoadableConstant[] staticArgs) {
2419             super(0, name, type, owner);
2420             this.bsm = bsm;
2421             this.staticArgs = staticArgs;
2422         }
2423 
2424         @Override
2425         public Name name() {
2426             return name;
2427         }
2428 
2429         @Override
2430         public boolean isDynamic() {
2431             return true;
2432         }
2433 
2434         @Override
2435         public PoolConstant dynamicType() {
2436             return type;
2437         }
2438 
2439         @Override
2440         public LoadableConstant[] staticArgs() {
2441             return staticArgs;
2442         }
2443 
2444         @Override
2445         public LoadableConstant bootstrapMethod() {
2446             return bsm;
2447         }
2448 
2449         @Override
2450         public int poolTag() {
2451             return ClassFile.CONSTANT_Dynamic;
2452         }
2453     }
2454 
2455     /** A class for method handles.
2456      */
2457     public static class MethodHandleSymbol extends MethodSymbol implements LoadableConstant {
2458 
2459         private Symbol refSym;
2460         private boolean getter;
2461 
2462         public MethodHandleSymbol(Symbol msym) {
2463             this(msym, false);
2464         }
2465 
2466         public MethodHandleSymbol(Symbol msym, boolean getter) {
2467             super(msym.flags_field, msym.name, msym.type, msym.owner);
2468             this.refSym = msym;
2469             this.getter = getter;
2470         }
2471 
2472         /**
2473          * Returns the kind associated with this method handle.
2474          */
2475         public int referenceKind() {
2476             if (refSym.kind == VAR) {
2477                 return getter ?
2478                         refSym.isStatic() ? ClassFile.REF_getStatic : ClassFile.REF_getField :
2479                         refSym.isStatic() ? ClassFile.REF_putStatic : ClassFile.REF_putField;
2480             } else {
2481                 if (refSym.isConstructor()) {
2482                     return ClassFile.REF_newInvokeSpecial;
2483                 } else {
2484                     if (refSym.isStatic()) {
2485                         return ClassFile.REF_invokeStatic;
2486                     } else if ((refSym.flags() & PRIVATE) != 0 && !allowPrivateInvokeVirtual()) {
2487                         return ClassFile.REF_invokeSpecial;
2488                     } else if (refSym.enclClass().isInterface()) {
2489                         return ClassFile.REF_invokeInterface;
2490                     } else {
2491                         return ClassFile.REF_invokeVirtual;
2492                     }
2493                 }
2494             }
2495         }
2496 
2497         private boolean allowPrivateInvokeVirtual() {
2498             Symbol rootPack = this;
2499             while (rootPack != null && !(rootPack instanceof RootPackageSymbol)) {
2500                 rootPack = rootPack.owner;
2501             }
2502             return rootPack != null && ((RootPackageSymbol) rootPack).allowPrivateInvokeVirtual;
2503         }
2504         @Override
2505         public int poolTag() {
2506             return ClassFile.CONSTANT_MethodHandle;
2507         }
2508 
2509         @Override
2510         public Object poolKey(Types types) {
2511             return new Pair<>(baseSymbol(), referenceKind());
2512         }
2513 
2514         @Override
2515         public MethodHandleSymbol asHandle() {
2516             return this;
2517         }
2518 
2519         @Override
2520         public Symbol baseSymbol() {
2521             return refSym;
2522         }
2523 
2524 
2525         @Override
2526         public boolean isHandle() {
2527             return true;
2528         }
2529     }
2530 
2531     /** A class for predefined operators.
2532      */
2533     public static class OperatorSymbol extends MethodSymbol {
2534 
2535         public int opcode;
2536         private int accessCode = Integer.MIN_VALUE;
2537 
2538         public OperatorSymbol(Name name, Type type, int opcode, Symbol owner) {
2539             super(PUBLIC | STATIC, name, type, owner);
2540             this.opcode = opcode;
2541         }
2542 
2543         @Override
2544         public <R, P> R accept(Symbol.Visitor<R, P> v, P p) {
2545             return v.visitOperatorSymbol(this, p);
2546         }
2547 
2548         public int getAccessCode(Tag tag) {
2549             if (accessCode != Integer.MIN_VALUE && !tag.isIncOrDecUnaryOp()) {
2550                 return accessCode;
2551             }
2552             accessCode = AccessCode.from(tag, opcode);
2553             return accessCode;
2554         }
2555 
2556         /** Access codes for dereferencing, assignment,
2557          *  and pre/post increment/decrement.
2558 
2559          *  All access codes for accesses to the current class are even.
2560          *  If a member of the superclass should be accessed instead (because
2561          *  access was via a qualified super), add one to the corresponding code
2562          *  for the current class, making the number odd.
2563          *  This numbering scheme is used by the backend to decide whether
2564          *  to issue an invokevirtual or invokespecial call.
2565          *
2566          *  @see Gen#visitSelect(JCFieldAccess tree)
2567          */
2568         public enum AccessCode {
2569             UNKNOWN(-1, Tag.NO_TAG),
2570             DEREF(0, Tag.NO_TAG),
2571             ASSIGN(2, Tag.ASSIGN),
2572             PREINC(4, Tag.PREINC),
2573             PREDEC(6, Tag.PREDEC),
2574             POSTINC(8, Tag.POSTINC),
2575             POSTDEC(10, Tag.POSTDEC),
2576             FIRSTASGOP(12, Tag.NO_TAG);
2577 
2578             public final int code;
2579             public final Tag tag;
2580             public static final int numberOfAccessCodes = (lushrl - ishll + lxor + 2 - iadd) * 2 + FIRSTASGOP.code + 2;
2581 
2582             AccessCode(int code, Tag tag) {
2583                 this.code = code;
2584                 this.tag = tag;
2585             }
2586 
2587             public static AccessCode getFromCode(int code) {
2588                 for (AccessCode aCodes : AccessCode.values()) {
2589                     if (aCodes.code == code) {
2590                         return aCodes;
2591                     }
2592                 }
2593                 return UNKNOWN;
2594             }
2595 
2596             static int from(Tag tag, int opcode) {
2597                 /** Map bytecode of binary operation to access code of corresponding
2598                 *  assignment operation. This is always an even number.
2599                 */
2600                 switch (tag) {
2601                     case PREINC:
2602                         return AccessCode.PREINC.code;
2603                     case PREDEC:
2604                         return AccessCode.PREDEC.code;
2605                     case POSTINC:
2606                         return AccessCode.POSTINC.code;
2607                     case POSTDEC:
2608                         return AccessCode.POSTDEC.code;
2609                 }
2610                 if (iadd <= opcode && opcode <= lxor) {
2611                     return (opcode - iadd) * 2 + FIRSTASGOP.code;
2612                 } else if (opcode == string_add) {
2613                     return (lxor + 1 - iadd) * 2 + FIRSTASGOP.code;
2614                 } else if (ishll <= opcode && opcode <= lushrl) {
2615                     return (opcode - ishll + lxor + 2 - iadd) * 2 + FIRSTASGOP.code;
2616                 }
2617                 return -1;
2618             }
2619         }
2620     }
2621 
2622     /** Symbol completer interface.
2623      */
2624     public static interface Completer {
2625 
2626         /** Dummy completer to be used when the symbol has been completed or
2627          * does not need completion.
2628          */
2629         public static final Completer NULL_COMPLETER = new Completer() {
2630             public void complete(Symbol sym) { }
2631             public boolean isTerminal() { return true; }
2632         };
2633 
2634         void complete(Symbol sym) throws CompletionFailure;
2635 
2636         /** Returns true if this completer is <em>terminal</em>. A terminal
2637          * completer is used as a place holder when the symbol is completed.
2638          * Calling complete on a terminal completer will not affect the symbol.
2639          *
2640          * The dummy NULL_COMPLETER and the GraphDependencies completer are
2641          * examples of terminal completers.
2642          *
2643          * @return true iff this completer is terminal
2644          */
2645         default boolean isTerminal() {
2646             return false;
2647         }
2648     }
2649 
2650     public static class CompletionFailure extends RuntimeException {
2651         private static final long serialVersionUID = 0;
2652         public final transient DeferredCompletionFailureHandler dcfh;
2653         public transient Symbol sym;
2654 
2655         /** A diagnostic object describing the failure
2656          */
2657         private transient JCDiagnostic diag;
2658 
2659         private transient Supplier<JCDiagnostic> diagSupplier;
2660 
2661         public CompletionFailure(Symbol sym, Supplier<JCDiagnostic> diagSupplier, DeferredCompletionFailureHandler dcfh) {
2662             this.dcfh = dcfh;
2663             this.sym = sym;
2664             this.diagSupplier = diagSupplier;
2665 //          this.printStackTrace();//DEBUG
2666         }
2667 
2668         public JCDiagnostic getDiagnostic() {
2669             if (diag == null && diagSupplier != null) {
2670                 diag = diagSupplier.get();
2671             }
2672             return diag;
2673         }
2674 
2675         @Override
2676         public String getMessage() {
2677             return getDiagnostic().getMessage(null);
2678         }
2679 
2680         public JCDiagnostic getDetailValue() {
2681             return getDiagnostic();
2682         }
2683 
2684         @Override
2685         public CompletionFailure initCause(Throwable cause) {
2686             super.initCause(cause);
2687             return this;
2688         }
2689 
2690         public void resetDiagnostic(Supplier<JCDiagnostic> diagSupplier) {
2691             this.diagSupplier = diagSupplier;
2692             this.diag = null;
2693         }
2694 
2695     }
2696 
2697     /**
2698      * A visitor for symbols.  A visitor is used to implement operations
2699      * (or relations) on symbols.  Most common operations on types are
2700      * binary relations and this interface is designed for binary
2701      * relations, that is, operations on the form
2702      * Symbol&nbsp;&times;&nbsp;P&nbsp;&rarr;&nbsp;R.
2703      * <!-- In plain text: Type x P -> R -->
2704      *
2705      * @param <R> the return type of the operation implemented by this
2706      * visitor; use Void if no return type is needed.
2707      * @param <P> the type of the second argument (the first being the
2708      * symbol itself) of the operation implemented by this visitor; use
2709      * Void if a second argument is not needed.
2710      */
2711     public interface Visitor<R,P> {
2712         R visitClassSymbol(ClassSymbol s, P arg);
2713         R visitMethodSymbol(MethodSymbol s, P arg);
2714         R visitPackageSymbol(PackageSymbol s, P arg);
2715         R visitOperatorSymbol(OperatorSymbol s, P arg);
2716         R visitVarSymbol(VarSymbol s, P arg);
2717         R visitTypeSymbol(TypeSymbol s, P arg);
2718         R visitSymbol(Symbol s, P arg);
2719     }
2720 }