symbol.java

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    public <A extends java.lang.annotation.Annotation> A getAnnotation(Class<A> annoType) {
        return JavacElements.getAnnotation(this, annoType);
    }

    // TODO: getEnclosedElements should return a javac List, fix in FilteredMemberList
    public java.util.List<Symbol> getEnclosedElements() {
        return List.nil();
    }

    public List<TypeSymbol> getTypeParameters() {
        ListBuffer<TypeSymbol> l = ListBuffer.lb();
        for (Type t : type.getTypeArguments()) {
            l.append(t.tsym);
        }
        return l.toList();
    }

    public static class DelegatedSymbol extends Symbol {
        protected Symbol other;
        public DelegatedSymbol(Symbol other) {
            super(other.kind, other.flags_field, other.name, other.type, other.owner);
            this.other = other;
        }
        public String toString() { return other.toString(); }
        public String location() { return other.location(); }
        public String location(Type site, Types types) { return other.location(site, types); }
        public Type erasure(Types types) { return other.erasure(types); }
        public Type externalType(Types types) { return other.externalType(types); }
        public boolean isLocal() { return other.isLocal(); }
        public boolean isConstructor() { return other.isConstructor(); }
        public Name getQualifiedName() { return other.getQualifiedName(); }
        public Name flatName() { return other.flatName(); }
        public Scope members() { return other.members(); }
        public boolean isInner() { return other.isInner(); }
        public boolean hasOuterInstance() { return other.hasOuterInstance(); }
        public ClassSymbol enclClass() { return other.enclClass(); }
        public ClassSymbol outermostClass() { return other.outermostClass(); }
        public PackageSymbol packge() { return other.packge(); }
        public boolean isSubClass(Symbol base, Types types) { return other.isSubClass(base, types); }
        public boolean isMemberOf(TypeSymbol clazz, Types types) { return other.isMemberOf(clazz, types); }
        public boolean isEnclosedBy(ClassSymbol clazz) { return other.isEnclosedBy(clazz); }
        public boolean isInheritedIn(Symbol clazz, Types types) { return other.isInheritedIn(clazz, types); }
        public Symbol asMemberOf(Type site, Types types) { return other.asMemberOf(site, types); }
        public void complete() throws CompletionFailure { other.complete(); }

        public <R, P> R accept(ElementVisitor<R, P> v, P p) {
            return other.accept(v, p);
        }
    }

    /** A class for type symbols. Type variables are represented by instances
     *  of this class, classes and packages by instances of subclasses.
     */
    public static class TypeSymbol
            extends Symbol implements TypeParameterElement {
        // Implements TypeParameterElement because type parameters don't
        // have their own TypeSymbol subclass.
        // TODO: type parameters should have their own TypeSymbol subclass

        public TypeSymbol(long flags, Name name, Type type, Symbol owner) {
            super(TYP, flags, name, type, owner);
        }

        /** form a fully qualified name from a name and an owner
         */
        static public Name formFullName(Name name, Symbol owner) {
            if (owner == null) return name;
            if (((owner.kind != ERR)) &&
                ((owner.kind & (VAR | MTH)) != 0
                 || (owner.kind == TYP && owner.type.tag == TYPEVAR)
                 )) return name;
            Name prefix = owner.getQualifiedName();
            if (prefix == null || prefix == prefix.table.empty)
                return name;
            else return prefix.append('.', name);
        }

        /** form a fully qualified name from a name and an owner, after
         *  converting to flat representation
         */
        static public Name formFlatName(Name name, Symbol owner) {
            if (owner == null ||
                (owner.kind & (VAR | MTH)) != 0
                || (owner.kind == TYP && owner.type.tag == TYPEVAR)
                ) return name;
            char sep = owner.kind == TYP ? '$' : '.';
            Name prefix = owner.flatName();
            if (prefix == null || prefix == prefix.table.empty)
                return name;
            else return prefix.append(sep, name);
        }

        /**
         * A total ordering between type symbols that refines the
         * class inheritance graph.
         *
         * Typevariables always precede other kinds of symbols.
         */
        public final boolean precedes(TypeSymbol that, Types types) {
            if (this == that)
                return false;
            if (this.type.tag == that.type.tag) {
                if (this.type.tag == CLASS) {
                    return
                        types.rank(that.type) < types.rank(this.type) ||
                        types.rank(that.type) == types.rank(this.type) &&
                        that.getQualifiedName().compareTo(this.getQualifiedName()) < 0;
                } else if (this.type.tag == TYPEVAR) {
                    return types.isSubtype(this.type, that.type);
                }
            }
            return this.type.tag == TYPEVAR;
        }

        // For type params; overridden in subclasses.
        public ElementKind getKind() {
            return ElementKind.TYPE_PARAMETER;
        }

        public java.util.List<Symbol> getEnclosedElements() {
            List<Symbol> list = List.nil();
            for (Scope.Entry e = members().elems; e != null; e = e.sibling) {
                if (e.sym != null && (e.sym.flags() & SYNTHETIC) == 0 && e.sym.owner == this)
                    list = list.prepend(e.sym);
            }
            return list;
        }

        // For type params.
        // Perhaps not needed if getEnclosingElement can be spec'ed
        // to do the same thing.
        // TODO: getGenericElement() might not be needed
        public Symbol getGenericElement() {
            return owner;
        }

        public <R, P> R accept(ElementVisitor<R, P> v, P p) {
            assert type.tag == TYPEVAR; // else override will be invoked
            return v.visitTypeParameter(this, p);
        }

        public List<Type> getBounds() {
            TypeVar t = (TypeVar)type;
            Type bound = t.getUpperBound();
            if (!bound.isCompound())
                return List.of(bound);
            ClassType ct = (ClassType)bound;
            if (!ct.tsym.erasure_field.isInterface()) {
                return ct.interfaces_field.prepend(ct.supertype_field);
            } else {
                // No superclass was given in bounds.
                // In this case, supertype is Object, erasure is first interface.
                return ct.interfaces_field;
            }
        }
    }

    /** A class for package symbols
     */
    public static class PackageSymbol extends TypeSymbol
        implements PackageElement {

        public Scope members_field;
        public Name fullname;
        public ClassSymbol package_info; // see bug 6443073

        public PackageSymbol(Name name, Type type, Symbol owner) {
            super(0, name, type, owner);
            this.kind = PCK;
            this.members_field = null;
            this.fullname = formFullName(name, owner);
        }

        public PackageSymbol(Name name, Symbol owner) {
            this(name, null, owner);
            this.type = new PackageType(this);
        }

        public String toString() {
            return fullname.toString();
        }

        public Name getQualifiedName() {
            return fullname;
        }

	public boolean isUnnamed() {
	    return name.isEmpty() && owner != null;
	}

        public Scope members() {
            if (completer != null) complete();
            return members_field;
        }

        public long flags() {
            if (completer != null) complete();
            return flags_field;
        }

        public List<Attribute.Compound> getAnnotationMirrors() {
            if (completer != null) complete();
            assert attributes_field != null;
            return attributes_field;
        }

        /** A package "exists" if a type or package that exists has
         *  been seen within it.
         */
        public boolean exists() {
            return (flags_field & EXISTS) != 0;
        }

        public ElementKind getKind() {
            return ElementKind.PACKAGE;
        }

        public Symbol getEnclosingElement() {
            return null;
        }

        public <R, P> R accept(ElementVisitor<R, P> v, P p) {
            return v.visitPackage(this, p);
        }
    }

    /** A class for class symbols
     */
    public static class ClassSymbol extends TypeSymbol implements TypeElement {

        /** a scope for all class members; variables, methods and inner classes
         *  type parameters are not part of this scope
         */
        public Scope members_field;

        /** the fully qualified name of the class, i.e. pck.outer.inner.
         *  null for anonymous classes
         */
        public Name fullname;

        /** the fully qualified name of the class after converting to flat
         *  representation, i.e. pck.outer$inner,
         *  set externally for local and anonymous classes
         */
        public Name flatname;

        /** the sourcefile where the class came from
         */
        public JavaFileObject sourcefile;

        /** the classfile from where to load this class
         *  this will have extension .class or .java
         */
        public JavaFileObject classfile;

        /** the constant pool of the class
         */
        public Pool pool;

        public ClassSymbol(long flags, Name name, Type type, Symbol owner) {
            super(flags, name, type, owner);
            this.members_field = null;
            this.fullname = formFullName(name, owner);
            this.flatname = formFlatName(name, owner);
            this.sourcefile = null;
            this.classfile = null;
            this.pool = null;
        }

        public ClassSymbol(long flags, Name name, Symbol owner) {
            this(
                flags,
                name,
                new ClassType(Type.noType, null, null),
                owner);
            this.type.tsym = this;
        }

        /** The Java source which this symbol represents.
         */
        public String toString() {
            return className();
        }

        public long flags() {
            if (completer != null) complete();
            return flags_field;
        }

        public Scope members() {
            if (completer != null) complete();
            return members_field;
        }

        public List<Attribute.Compound> getAnnotationMirrors() {
            if (completer != null) complete();
            assert attributes_field != null;
            return attributes_field;
        }

        public Type erasure(Types types) {
            if (erasure_field == null)
                erasure_field = new ClassType(types.erasure(type.getEnclosingType()),
                                              List.<Type>nil(), this);
            return erasure_field;
        }

        public String className() {
            if (name.len == 0)
                return
                    Log.getLocalizedString("anonymous.class", flatname);
            else
                return fullname.toString();
        }

        public Name getQualifiedName() {
            return fullname;
        }

        public Name flatName() {
            return flatname;
        }

        public boolean isSubClass(Symbol base, Types types) {
            if (this == base) {
                return true;
            } else if ((base.flags() & INTERFACE) != 0) {
                for (Type t = type; t.tag == CLASS; t = types.supertype(t))
                    for (List<Type> is = types.interfaces(t);
                         is.nonEmpty();
                         is = is.tail)
                        if (is.head.tsym.isSubClass(base, types)) return true;
            } else {
                for (Type t = type; t.tag == CLASS; t = types.supertype(t))
                    if (t.tsym == base) return true;
            }
            return false;
        }

        /** Complete the elaboration of this symbol's definition.
         */
        public void complete() throws CompletionFailure {
            try {
                super.complete();
            } catch (CompletionFailure ex) {
                // quiet error recovery
                flags_field |= (PUBLIC|STATIC);
                this.type = new ErrorType(this);
                throw ex;
            }
        }

        public List<Type> getInterfaces() {
            complete();
            if (type instanceof ClassType) {
                ClassType t = (ClassType)type;
                if (t.interfaces_field == null) // FIXME: shouldn't be null
                    t.interfaces_field = List.nil();
                return t.interfaces_field;
            } else {
                return List.nil();
            }
        }

        public Type getSuperclass() {
            complete();
            if (type instanceof ClassType) {
                ClassType t = (ClassType)type;
                if (t.supertype_field == null) // FIXME: shouldn't be null
                    t.supertype_field = Type.noType;
		// An interface has no superclass; its supertype is Object.
		return t.isInterface()
		    ? Type.noType
		    : t.supertype_field;
            } else {
                return Type.noType;
            }
        }

        public ElementKind getKind() {
            long flags = flags();
            if ((flags & ANNOTATION) != 0)
                return ElementKind.ANNOTATION_TYPE;
            else if ((flags & INTERFACE) != 0)
                return ElementKind.INTERFACE;
            else if ((flags & ENUM) != 0)
                return ElementKind.ENUM;
            else
                return ElementKind.CLASS;
        }

        public NestingKind getNestingKind() {
            complete();
            if (owner.kind == PCK)
                return NestingKind.TOP_LEVEL;
            else if (name.isEmpty())
                return NestingKind.ANONYMOUS;
            else if (owner.kind == MTH)
                return NestingKind.LOCAL;
            else
                return NestingKind.MEMBER;
        }

        /**
         * @deprecated this method should never be used by javac internally.
         */
        @Override @Deprecated
        public <A extends java.lang.annotation.Annotation> A getAnnotation(Class<A> annoType) {
            return JavacElements.getAnnotation(this, annoType);
        }

        public <R, P> R accept(ElementVisitor<R, P> v, P p) {
            return v.visitType(this, p);
        }
    }


    /** A class for variable symbols
     */
    public static class VarSymbol extends Symbol implements VariableElement {

        /** The variable's declaration position.
         */
        public int pos = Position.NOPOS;

        /** The variable's address. Used for different purposes during
         *  flow analysis, translation and code generation.
         *  Flow analysis:
         *    If this is a blank final or local variable, its sequence number.
         *  Translation:
         *    If this is a private field, its access number.
         *  Code generation:
         *    If this is a local variable, its logical slot number.