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 /*

  * Copyright (c) 1999, 2014, Oracle and/or its affiliates. All rights reserved.

  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.

  *

  * This code is free software; you can redistribute it and/or modify it

  * under the terms of the GNU General Public License version 2 only, as

  * published by the Free Software Foundation.  Oracle designates this

  * particular file as subject to the "Classpath" exception as provided

  * by Oracle in the LICENSE file that accompanied this code.

  *

  * This code is distributed in the hope that it will be useful, but WITHOUT

  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or

  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License

  * version 2 for more details (a copy is included in the LICENSE file that

  * accompanied this code).

  *

  * You should have received a copy of the GNU General Public License version

  * 2 along with this work; if not, write to the Free Software Foundation,

  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.

  *

  * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA

  * or visit www.oracle.com if you need additional information or have any

  * questions.

  */

 package com.sun.tools.javac.code;

 import java.lang.annotation.Annotation;

 import java.util.Collections;

 import java.util.EnumMap;

 import java.util.EnumSet;

 import java.util.Map;

 import java.util.Set;

 import javax.lang.model.type.*;

 import com.sun.tools.javac.code.Symbol.*;

 import com.sun.tools.javac.util.*;

 import static com.sun.tools.javac.code.BoundKind.*;

 import static com.sun.tools.javac.code.Flags.*;

 import static com.sun.tools.javac.code.Kinds.*;

 import static com.sun.tools.javac.code.TypeTag.*;

 /** This class represents Java types. The class itself defines the behavior of

  *  the following types:

  *  <pre>

  *  base types (tags: BYTE, CHAR, SHORT, INT, LONG, FLOAT, DOUBLE, BOOLEAN),

  *  type `void' (tag: VOID),

  *  the bottom type (tag: BOT),

  *  the missing type (tag: NONE).

  *  </pre>

  *  <p>The behavior of the following types is defined in subclasses, which are

  *  all static inner classes of this class:

  *  <pre>

  *  class types (tag: CLASS, class: ClassType),

  *  array types (tag: ARRAY, class: ArrayType),

  *  method types (tag: METHOD, class: MethodType),

  *  package types (tag: PACKAGE, class: PackageType),

  *  type variables (tag: TYPEVAR, class: TypeVar),

  *  type arguments (tag: WILDCARD, class: WildcardType),

  *  generic method types (tag: FORALL, class: ForAll),

  *  the error type (tag: ERROR, class: ErrorType).

  *  </pre>

  *

  *  <p><b>This is NOT part of any supported API.

  *  If you write code that depends on this, you do so at your own risk.

  *  This code and its internal interfaces are subject to change or

  *  deletion without notice.</b>

  *

  *  @see TypeTag

  */

 public abstract class Type extends AnnoConstruct implements TypeMirror {

     /** Constant type: no type at all. */

     public static final JCNoType noType = new JCNoType() {

         @Override

         public String toString() {

             return "none";

         }

     };

     /** Constant type: special type to be used during recovery of deferred expressions. */

     public static final JCNoType recoveryType = new JCNoType(){

         @Override

         public String toString() {

             return "recovery";

         }

     };

     /** Constant type: special type to be used for marking stuck trees. */

     public static final JCNoType stuckType = new JCNoType() {

         @Override

         public String toString() {

             return "stuck";

         }

     };

     /** If this switch is turned on, the names of type variables

      *  and anonymous classes are printed with hashcodes appended.

      */

     public static boolean moreInfo = false;

     /** The defining class / interface / package / type variable.

      */

     public TypeSymbol tsym;

     /**

      * Checks if the current type tag is equal to the given tag.

      * @return true if tag is equal to the current type tag.

      */

     public boolean hasTag(TypeTag tag) {

         return tag == getTag();

     }

     /**

      * Returns the current type tag.

      * @return the value of the current type tag.

      */

     public abstract TypeTag getTag();

     public boolean isNumeric() {

         return false;

     }

     public boolean isPrimitive() {

         return false;

     }

     public boolean isPrimitiveOrVoid() {

         return false;

     }

     public boolean isReference() {

         return false;

     }

     public boolean isNullOrReference() {

         return false;

     }

     public boolean isPartial() {

         return false;

     }

     /**

      * The constant value of this type, null if this type does not

      * have a constant value attribute. Only primitive types and

      * strings (ClassType) can have a constant value attribute.

      * @return the constant value attribute of this type

      */

     public Object constValue() {

         return null;

     }

     /** Is this a constant type whose value is false?

      */

     public boolean isFalse() {

         return false;

     }

     /** Is this a constant type whose value is true?

      */

     public boolean isTrue() {

         return false;

     }

     /**

      * Get the representation of this type used for modelling purposes.

      * By default, this is itself. For ErrorType, a different value

      * may be provided.

      */

     public Type getModelType() {

         return this;

     }

     public static List<Type> getModelTypes(List<Type> ts) {

         ListBuffer<Type> lb = new ListBuffer<>();

         for (Type t: ts)

             lb.append(t.getModelType());

         return lb.toList();

     }

     /**For ErrorType, returns the original type, otherwise returns the type itself.

      */

     public Type getOriginalType() {

         return this;

     }

     public <R,S> R accept(Type.Visitor<R,S> v, S s) { return v.visitType(this, s); }

     /** Define a type given its tag and type symbol

      */

     public Type(TypeSymbol tsym) {

         this.tsym = tsym;

     }

     /** An abstract class for mappings from types to types

      */

     public static abstract class Mapping {

         private String name;

         public Mapping(String name) {

             this.name = name;

         }

         public abstract Type apply(Type t);

         public String toString() {

             return name;

         }

     }

     /** map a type function over all immediate descendants of this type

      */

     public Type map(Mapping f) {

         return this;

     }

     /** map a type function over a list of types

      */

     public static List<Type> map(List<Type> ts, Mapping f) {

         if (ts.nonEmpty()) {

             List<Type> tail1 = map(ts.tail, f);

             Type t = f.apply(ts.head);

             if (tail1 != ts.tail || t != ts.head)

                 return tail1.prepend(t);

         }

         return ts;

     }

     /** Define a constant type, of the same kind as this type

      *  and with given constant value

      */

     public Type constType(Object constValue) {

         throw new AssertionError();

     }

     /**

      * If this is a constant type, return its underlying type.

      * Otherwise, return the type itself.

      */

     public Type baseType() {

         return this;

     }

     public Type annotatedType(List<Attribute.TypeCompound> annos) {

         return new AnnotatedType(annos, this);

     }

     public boolean isAnnotated() {

         return false;

     }

     /**

      * If this is an annotated type, return the underlying type.

      * Otherwise, return the type itself.

      */

     public Type unannotatedType() {

         return this;

     }

     @Override

     public List<Attribute.TypeCompound> getAnnotationMirrors() {

         return List.nil();

     }

     @Override

     public <A extends Annotation> A getAnnotation(Class<A> annotationType) {

         return null;

     }

     @Override

     public <A extends Annotation> A[] getAnnotationsByType(Class<A> annotationType) {

         @SuppressWarnings("unchecked")

         A[] tmp = (A[]) java.lang.reflect.Array.newInstance(annotationType, 0);

         return tmp;

     }

     /** Return the base types of a list of types.

      */

     public static List<Type> baseTypes(List<Type> ts) {

         if (ts.nonEmpty()) {

             Type t = ts.head.baseType();

             List<Type> baseTypes = baseTypes(ts.tail);

             if (t != ts.head || baseTypes != ts.tail)

                 return baseTypes.prepend(t);

         }

         return ts;

     }

     /** The Java source which this type represents.

      */

     public String toString() {

         String s = (tsym == null || tsym.name == null)

             ? "<none>"

             : tsym.name.toString();

         if (moreInfo && hasTag(TYPEVAR)) {

             s = s + hashCode();

         }

         return s;

     }

     /**

      * The Java source which this type list represents.  A List is

      * represented as a comma-spearated listing of the elements in

      * that list.

      */

     public static String toString(List<Type> ts) {

         if (ts.isEmpty()) {

             return "";

         } else {

             StringBuilder buf = new StringBuilder();

             buf.append(ts.head.toString());

             for (List<Type> l = ts.tail; l.nonEmpty(); l = l.tail)

                 buf.append(",").append(l.head.toString());

             return buf.toString();

         }

     }

     /**

      * The constant value of this type, converted to String

      */

     public String stringValue() {

         Object cv = Assert.checkNonNull(constValue());

         return cv.toString();

     }

     /**

      * This method is analogous to isSameType, but weaker, since we

      * never complete classes. Where isSameType would complete a

      * class, equals assumes that the two types are different.

      */

     @Override

     public boolean equals(Object t) {

         return super.equals(t);

     }

     @Override

     public int hashCode() {

         return super.hashCode();

     }

     public String argtypes(boolean varargs) {

         List<Type> args = getParameterTypes();

         if (!varargs) return args.toString();

         StringBuilder buf = new StringBuilder();

         while (args.tail.nonEmpty()) {

             buf.append(args.head);

             args = args.tail;

             buf.append(',');

         }

         if (args.head.unannotatedType().hasTag(ARRAY)) {

             buf.append(((ArrayType)args.head.unannotatedType()).elemtype);

             if (args.head.getAnnotationMirrors().nonEmpty()) {

                 buf.append(args.head.getAnnotationMirrors());

             }

             buf.append("...");

         } else {

             buf.append(args.head);

         }

         return buf.toString();

     }

     /** Access methods.

      */

     public List<Type>        getTypeArguments()  { return List.nil(); }

     public Type              getEnclosingType()  { return null; }

     public List<Type>        getParameterTypes() { return List.nil(); }

     public Type              getReturnType()     { return null; }

     public Type              getReceiverType()   { return null; }

     public List<Type>        getThrownTypes()    { return List.nil(); }

     public Type              getUpperBound()     { return null; }

     public Type              getLowerBound()     { return null; }

     /** Navigation methods, these will work for classes, type variables,

      *  foralls, but will return null for arrays and methods.

      */

    /** Return all parameters of this type and all its outer types in order

     *  outer (first) to inner (last).

     */

     public List<Type> allparams() { return List.nil(); }

     /** Does this type contain "error" elements?

      */

     public boolean isErroneous() {

         return false;

     }

     public static boolean isErroneous(List<Type> ts) {

         for (List<Type> l = ts; l.nonEmpty(); l = l.tail)

             if (l.head.isErroneous()) return true;

         return false;

     }

     /** Is this type parameterized?

      *  A class type is parameterized if it has some parameters.

      *  An array type is parameterized if its element type is parameterized.

      *  All other types are not parameterized.

      */

     public boolean isParameterized() {

         return false;

     }

     /** Is this type a raw type?

      *  A class type is a raw type if it misses some of its parameters.

      *  An array type is a raw type if its element type is raw.

      *  All other types are not raw.

      *  Type validation will ensure that the only raw types

      *  in a program are types that miss all their type variables.

      */

     public boolean isRaw() {

         return false;

     }

     public boolean isCompound() {

         return tsym.completer == null

             // Compound types can't have a completer.  Calling

             // flags() will complete the symbol causing the

             // compiler to load classes unnecessarily.  This led

             // to regression 6180021.

             && (tsym.flags() & COMPOUND) != 0;

     }

     public boolean isIntersection() {

         return false;

     }

     public boolean isUnion() {

         return false;

     }

     public boolean isInterface() {

         return (tsym.flags() & INTERFACE) != 0;

     }

     public boolean isFinal() {

         return (tsym.flags() & FINAL) != 0;

     }

     /**

      * Does this type contain occurrences of type t?

      */

     public boolean contains(Type t) {

         return t == this;

     }

     public static boolean contains(List<Type> ts, Type t) {

         for (List<Type> l = ts;

              l.tail != null /*inlined: l.nonEmpty()*/;

              l = l.tail)

             if (l.head.contains(t)) return true;

         return false;

     }

     /** Does this type contain an occurrence of some type in 'ts'?

      */

     public boolean containsAny(List<Type> ts) {

         for (Type t : ts)

             if (this.contains(t)) return true;

         return false;

     }

     public static boolean containsAny(List<Type> ts1, List<Type> ts2) {

         for (Type t : ts1)

             if (t.containsAny(ts2)) return true;

         return false;

     }

     public static List<Type> filter(List<Type> ts, Filter<Type> tf) {

         ListBuffer<Type> buf = new ListBuffer<>();

         for (Type t : ts) {

             if (tf.accepts(t)) {

                 buf.append(t);

             }

         }

         return buf.toList();

     }

     public boolean isSuperBound() { return false; }

     public boolean isExtendsBound() { return false; }

     public boolean isUnbound() { return false; }

     public Type withTypeVar(Type t) { return this; }

     /** The underlying method type of this type.

      */

     public MethodType asMethodType() { throw new AssertionError(); }

     /** Complete loading all classes in this type.

      */

     public void complete() {}

     public TypeSymbol asElement() {

         return tsym;

     }

     @Override

     public TypeKind getKind() {

         return TypeKind.OTHER;

     }

     @Override

     public <R, P> R accept(TypeVisitor<R, P> v, P p) {

         throw new AssertionError();

     }

     public static class JCPrimitiveType extends Type

             implements javax.lang.model.type.PrimitiveType {

         TypeTag tag;

         public JCPrimitiveType(TypeTag tag, TypeSymbol tsym) {

             super(tsym);

             this.tag = tag;

             Assert.check(tag.isPrimitive);

         }

         @Override

         public boolean isNumeric() {

             return tag != BOOLEAN;

         }

         @Override

         public boolean isPrimitive() {

             return true;

         }

         @Override

         public TypeTag getTag() {

             return tag;

         }

         @Override

         public boolean isPrimitiveOrVoid() {

             return true;

         }

         /** Define a constant type, of the same kind as this type

          *  and with given constant value

          */

         @Override

         public Type constType(Object constValue) {

             final Object value = constValue;

             return new JCPrimitiveType(tag, tsym) {

                     @Override

                     public Object constValue() {

                         return value;

                     }

                     @Override

                     public Type baseType() {

                         return tsym.type;

                     }

                 };

         }

         /**

          * The constant value of this type, converted to String

          */

         @Override

         public String stringValue() {

             Object cv = Assert.checkNonNull(constValue());

             if (tag == BOOLEAN) {

                 return ((Integer) cv).intValue() == 0 ? "false" : "true";

             }

             else if (tag == CHAR) {

                 return String.valueOf((char) ((Integer) cv).intValue());

             }

             else {

                 return cv.toString();

             }

         }

         /** Is this a constant type whose value is false?

          */

         @Override

         public boolean isFalse() {

             return

                 tag == BOOLEAN &&

                 constValue() != null &&

                 ((Integer)constValue()).intValue() == 0;

         }

         /** Is this a constant type whose value is true?

          */

         @Override

         public boolean isTrue() {

             return

                 tag == BOOLEAN &&

                 constValue() != null &&

                 ((Integer)constValue()).intValue() != 0;

         }

         @Override

         public <R, P> R accept(TypeVisitor<R, P> v, P p) {

             return v.visitPrimitive(this, p);

         }

         @Override

         public TypeKind getKind() {

             switch (tag) {

                 case BYTE:      return TypeKind.BYTE;

                 case CHAR:      return TypeKind.CHAR;

                 case SHORT:     return TypeKind.SHORT;

                 case INT:       return TypeKind.INT;

                 case LONG:      return TypeKind.LONG;

                 case FLOAT:     return TypeKind.FLOAT;

                 case DOUBLE:    return TypeKind.DOUBLE;

                 case BOOLEAN:   return TypeKind.BOOLEAN;

             }

             throw new AssertionError();

         }

     }

     public static class WildcardType extends Type

             implements javax.lang.model.type.WildcardType {

         public Type type;

         public BoundKind kind;

         public TypeVar bound;

         @Override

         public <R,S> R accept(Type.Visitor<R,S> v, S s) {

             return v.visitWildcardType(this, s);

         }

         public WildcardType(Type type, BoundKind kind, TypeSymbol tsym) {

             super(tsym);

             this.type = Assert.checkNonNull(type);

             this.kind = kind;

         }

         public WildcardType(WildcardType t, TypeVar bound) {

             this(t.type, t.kind, t.tsym, bound);

         }

         public WildcardType(Type type, BoundKind kind, TypeSymbol tsym, TypeVar bound) {

             this(type, kind, tsym);

             this.bound = bound;

         }

         @Override

         public TypeTag getTag() {

             return WILDCARD;

         }

         @Override

         public boolean contains(Type t) {

             return kind != UNBOUND && type.contains(t);

         }

         public boolean isSuperBound() {

             return kind == SUPER ||

                 kind == UNBOUND;

         }

         public boolean isExtendsBound() {

             return kind == EXTENDS ||

                 kind == UNBOUND;

         }

         public boolean isUnbound() {

             return kind == UNBOUND;

         }

         @Override

         public boolean isReference() {

             return true;

         }

         @Override

         public boolean isNullOrReference() {

             return true;

         }

         @Override

         public Type withTypeVar(Type t) {

             //-System.err.println(this+".withTypeVar("+t+");");//DEBUG

             if (bound == t)

                 return this;

             bound = (TypeVar)t;

             return this;

         }

         boolean isPrintingBound = false;

         public String toString() {

             StringBuilder s = new StringBuilder();

             s.append(kind.toString());

             if (kind != UNBOUND)

                 s.append(type);

             if (moreInfo && bound != null && !isPrintingBound)

                 try {

                     isPrintingBound = true;

                     s.append("{:").append(bound.bound).append(":}");

                 } finally {

                     isPrintingBound = false;

                 }

             return s.toString();

         }

         public Type map(Mapping f) {

             //- System.err.println("   (" + this + ").map(" + f + ")");//DEBUG

             Type t = type;

             if (t != null)

                 t = f.apply(t);

             if (t == type)

                 return this;

             else

                 return new WildcardType(t, kind, tsym, bound);

         }

         public Type getExtendsBound() {

             if (kind == EXTENDS)

                 return type;

             else

                 return null;

         }

         public Type getSuperBound() {

             if (kind == SUPER)

                 return type;

             else

                 return null;

         }

         public TypeKind getKind() {

             return TypeKind.WILDCARD;

         }

         public <R, P> R accept(TypeVisitor<R, P> v, P p) {

             return v.visitWildcard(this, p);

         }

     }

     public static class ClassType extends Type implements DeclaredType {

         /** The enclosing type of this type. If this is the type of an inner

          *  class, outer_field refers to the type of its enclosing

          *  instance class, in all other cases it refers to noType.

          */

         private Type outer_field;

         /** The type parameters of this type (to be set once class is loaded).

          */

         public List<Type> typarams_field;

         /** A cache variable for the type parameters of this type,

          *  appended to all parameters of its enclosing class.

          *  @see #allparams

          */

         public List<Type> allparams_field;

         /** The supertype of this class (to be set once class is loaded).

          */

         public Type supertype_field;

         /** The interfaces of this class (to be set once class is loaded).

          */

         public List<Type> interfaces_field;

         /** All the interfaces of this class, including missing ones.

          */

         public List<Type> all_interfaces_field;

         public ClassType(Type outer, List<Type> typarams, TypeSymbol tsym) {

             super(tsym);

             this.outer_field = outer;

             this.typarams_field = typarams;

             this.allparams_field = null;

             this.supertype_field = null;

             this.interfaces_field = null;

             /*

             // this can happen during error recovery

             assert

                 outer.isParameterized() ?

                 typarams.length() == tsym.type.typarams().length() :

                 outer.isRaw() ?

                 typarams.length() == 0 :

                 true;

             */

         }

         @Override

         public TypeTag getTag() {

             return CLASS;

         }

         @Override

         public <R,S> R accept(Type.Visitor<R,S> v, S s) {

             return v.visitClassType(this, s);

         }

         public Type constType(Object constValue) {

             final Object value = constValue;

             return new ClassType(getEnclosingType(), typarams_field, tsym) {

                     @Override

                     public Object constValue() {

                         return value;

                     }

                     @Override

                     public Type baseType() {

                         return tsym.type;

                     }

                 };

         }

         /** The Java source which this type represents.

          */

         public String toString() {

             StringBuilder buf = new StringBuilder();

             if (getEnclosingType().hasTag(CLASS) && tsym.owner.kind == TYP) {

                 buf.append(getEnclosingType().toString());

                 buf.append(".");

                 buf.append(className(tsym, false));

             } else {

                 buf.append(className(tsym, true));

             }

             if (getTypeArguments().nonEmpty()) {

                 buf.append('<');

                 buf.append(getTypeArguments().toString());

                 buf.append(">");

             }

             return buf.toString();

         }

 //where

             private String className(Symbol sym, boolean longform) {

                 if (sym.name.isEmpty() && (sym.flags() & COMPOUND) != 0) {

                     StringBuilder s = new StringBuilder(supertype_field.toString());

                     for (List<Type> is=interfaces_field; is.nonEmpty(); is = is.tail) {

                         s.append("&");

                         s.append(is.head.toString());

                     }

                     return s.toString();

                 } else if (sym.name.isEmpty()) {

                     String s;

                     ClassType norm = (ClassType) tsym.type.unannotatedType();

                     if (norm == null) {

                         s = Log.getLocalizedString("anonymous.class", (Object)null);

                     } else if (norm.interfaces_field != null && norm.interfaces_field.nonEmpty()) {

                         s = Log.getLocalizedString("anonymous.class",

                                                    norm.interfaces_field.head);

                     } else {

                         s = Log.getLocalizedString("anonymous.class",

                                                    norm.supertype_field);

                     }

                     if (moreInfo)

                         s += String.valueOf(sym.hashCode());

                     return s;

                 } else if (longform) {

                     return sym.getQualifiedName().toString();

                 } else {

                     return sym.name.toString();

                 }

             }

         public List<Type> getTypeArguments() {

             if (typarams_field == null) {

                 complete();

                 if (typarams_field == null)

                     typarams_field = List.nil();

             }

             return typarams_field;

         }

         public boolean hasErasedSupertypes() {

             return isRaw();

         }

         public Type getEnclosingType() {

             return outer_field;

         }

         public void setEnclosingType(Type outer) {

             outer_field = outer;

         }

         public List<Type> allparams() {

             if (allparams_field == null) {

                 allparams_field = getTypeArguments().prependList(getEnclosingType().allparams());

             }

             return allparams_field;

         }

         public boolean isErroneous() {

             return

                 getEnclosingType().isErroneous() ||

                 isErroneous(getTypeArguments()) ||

                 this != tsym.type.unannotatedType() && tsym.type.isErroneous();

         }

         public boolean isParameterized() {

             return allparams().tail != null;

             // optimization, was: allparams().nonEmpty();

         }

         @Override

         public boolean isReference() {

             return true;

         }

         @Override

         public boolean isNullOrReference() {

             return true;

         }

         /** A cache for the rank. */

         int rank_field = -1;

         /** A class type is raw if it misses some

          *  of its type parameter sections.

          *  After validation, this is equivalent to:

          *  {@code allparams.isEmpty() && tsym.type.allparams.nonEmpty(); }

          */

         public boolean isRaw() {

             return

                 this != tsym.type && // necessary, but not sufficient condition

                 tsym.type.allparams().nonEmpty() &&

                 allparams().isEmpty();

         }

         public Type map(Mapping f) {

             Type outer = getEnclosingType();

             Type outer1 = f.apply(outer);

             List<Type> typarams = getTypeArguments();

             List<Type> typarams1 = map(typarams, f);

             if (outer1 == outer && typarams1 == typarams) return this;

             else return new ClassType(outer1, typarams1, tsym);

         }

         public boolean contains(Type elem) {

             return

                 elem == this

                 || (isParameterized()

                     && (getEnclosingType().contains(elem) || contains(getTypeArguments(), elem)))

                 || (isCompound()

                     && (supertype_field.contains(elem) || contains(interfaces_field, elem)));

         }

         public void complete() {

             if (tsym.completer != null) tsym.complete();

         }

         public TypeKind getKind() {

             return TypeKind.DECLARED;

         }

         public <R, P> R accept(TypeVisitor<R, P> v, P p) {

             return v.visitDeclared(this, p);

         }

     }

     public static class ErasedClassType extends ClassType {

         public ErasedClassType(Type outer, TypeSymbol tsym) {

             super(outer, List.<Type>nil(), tsym);

         }

         @Override

         public boolean hasErasedSupertypes() {

             return true;

         }

     }

     // a clone of a ClassType that knows about the alternatives of a union type.

     public static class UnionClassType extends ClassType implements UnionType {

         final List<? extends Type> alternatives_field;

         public UnionClassType(ClassType ct, List<? extends Type> alternatives) {

             super(ct.outer_field, ct.typarams_field, ct.tsym);

             allparams_field = ct.allparams_field;

             supertype_field = ct.supertype_field;

             interfaces_field = ct.interfaces_field;

             all_interfaces_field = ct.interfaces_field;

             alternatives_field = alternatives;

         }

         public Type getLub() {

             return tsym.type;

         }

         public java.util.List<? extends TypeMirror> getAlternatives() {

             return Collections.unmodifiableList(alternatives_field);

         }

         @Override

         public boolean isUnion() {

             return true;

         }

         @Override

         public TypeKind getKind() {

             return TypeKind.UNION;

         }

         @Override

         public <R, P> R accept(TypeVisitor<R, P> v, P p) {

             return v.visitUnion(this, p);

         }

     }

     // a clone of a ClassType that knows about the bounds of an intersection type.

     public static class IntersectionClassType extends ClassType implements IntersectionType {

         public boolean allInterfaces;

         public IntersectionClassType(List<Type> bounds, ClassSymbol csym, boolean allInterfaces) {

             super(Type.noType, List.<Type>nil(), csym);

             this.allInterfaces = allInterfaces;

             Assert.check((csym.flags() & COMPOUND) != 0);

             supertype_field = bounds.head;

             interfaces_field = bounds.tail;

             Assert.check(supertype_field.tsym.completer != null ||

                     !supertype_field.isInterface(), supertype_field);

         }

         public java.util.List<? extends TypeMirror> getBounds() {

             return Collections.unmodifiableList(getExplicitComponents());

         }

         public List<Type> getComponents() {

             return interfaces_field.prepend(supertype_field);

         }

         @Override

         public boolean isIntersection() {

             return true;

         }

         public List<Type> getExplicitComponents() {

             return allInterfaces ?

                     interfaces_field :

                     getComponents();

         }

         @Override

         public TypeKind getKind() {

             return TypeKind.INTERSECTION;

         }

         @Override

         public <R, P> R accept(TypeVisitor<R, P> v, P p) {

             return v.visitIntersection(this, p);

         }

     }

     public static class ArrayType extends Type

             implements javax.lang.model.type.ArrayType {

         public Type elemtype;

         public ArrayType(Type elemtype, TypeSymbol arrayClass) {

             super(arrayClass);

             this.elemtype = elemtype;

         }

         @Override

         public TypeTag getTag() {

             return ARRAY;

         }

         public <R,S> R accept(Type.Visitor<R,S> v, S s) {

             return v.visitArrayType(this, s);

         }

         public String toString() {

             return elemtype + "[]";

         }

         public boolean equals(Object obj) {

             return

                 this == obj ||

                 (obj instanceof ArrayType &&

                  this.elemtype.equals(((ArrayType)obj).elemtype));

         }

         public int hashCode() {

             return (ARRAY.ordinal() << 5) + elemtype.hashCode();

         }

         public boolean isVarargs() {

             return false;

         }

         public List<Type> allparams() { return elemtype.allparams(); }

         public boolean isErroneous() {

             return elemtype.isErroneous();

         }

         public boolean isParameterized() {

             return elemtype.isParameterized();

         }

         @Override

         public boolean isReference() {

             return true;

         }

         @Override

         public boolean isNullOrReference() {

             return true;

         }

         public boolean isRaw() {

             return elemtype.isRaw();

         }

         public ArrayType makeVarargs() {

             return new ArrayType(elemtype, tsym) {

                 @Override

                 public boolean isVarargs() {

                     return true;

                 }

             };

         }

         public Type map(Mapping f) {

             Type elemtype1 = f.apply(elemtype);

             if (elemtype1 == elemtype) return this;

             else return new ArrayType(elemtype1, tsym);

         }

         public boolean contains(Type elem) {

             return elem == this || elemtype.contains(elem);

         }

         public void complete() {

             elemtype.complete();

         }

         public Type getComponentType() {

             return elemtype;

         }

         public TypeKind getKind() {

             return TypeKind.ARRAY;

         }

         public <R, P> R accept(TypeVisitor<R, P> v, P p) {

             return v.visitArray(this, p);

         }

     }

     public static class MethodType extends Type implements ExecutableType {

         public List<Type> argtypes;

         public Type restype;

         public List<Type> thrown;

         /** The type annotations on the method receiver.

          */

         public Type recvtype;

         public MethodType(List<Type> argtypes,

                           Type restype,

                           List<Type> thrown,

                           TypeSymbol methodClass) {

             super(methodClass);

             this.argtypes = argtypes;

             this.restype = restype;

             this.thrown = thrown;

         }

         @Override

         public TypeTag getTag() {

             return METHOD;

         }

         public <R,S> R accept(Type.Visitor<R,S> v, S s) {

             return v.visitMethodType(this, s);

         }

         /** The Java source which this type represents.

          *

          *  XXX 06/09/99 iris This isn't correct Java syntax, but it probably

          *  should be.

          */

         public String toString() {

             return "(" + argtypes + ")" + restype;

         }

         public List<Type>        getParameterTypes() { return argtypes; }

         public Type              getReturnType()     { return restype; }

         public Type              getReceiverType()   { return recvtype; }

         public List<Type>        getThrownTypes()    { return thrown; }

         public boolean isErroneous() {

             return

                 isErroneous(argtypes) ||

                 restype != null && restype.isErroneous();

         }

         public Type map(Mapping f) {

             List<Type> argtypes1 = map(argtypes, f);

             Type restype1 = f.apply(restype);

             List<Type> thrown1 = map(thrown, f);

             if (argtypes1 == argtypes &&

                 restype1 == restype &&

                 thrown1 == thrown) return this;

             else return new MethodType(argtypes1, restype1, thrown1, tsym);

         }

         public boolean contains(Type elem) {

             return elem == this || contains(argtypes, elem) || restype.contains(elem) || contains(thrown, elem);

         }

         public MethodType asMethodType() { return this; }

         public void complete() {

             for (List<Type> l = argtypes; l.nonEmpty(); l = l.tail)

                 l.head.complete();

             restype.complete();

             recvtype.complete();

             for (List<Type> l = thrown; l.nonEmpty(); l = l.tail)

                 l.head.complete();

         }

         public List<TypeVar> getTypeVariables() {

             return List.nil();

         }

         public TypeSymbol asElement() {

             return null;

         }

         public TypeKind getKind() {

             return TypeKind.EXECUTABLE;

         }

         public <R, P> R accept(TypeVisitor<R, P> v, P p) {

             return v.visitExecutable(this, p);

         }

     }

     public static class PackageType extends Type implements NoType {

         PackageType(TypeSymbol tsym) {

             super(tsym);

         }

         @Override

         public TypeTag getTag() {

             return PACKAGE;

         }

         @Override

         public <R,S> R accept(Type.Visitor<R,S> v, S s) {

             return v.visitPackageType(this, s);

         }

         public String toString() {

             return tsym.getQualifiedName().toString();

         }

         public TypeKind getKind() {

             return TypeKind.PACKAGE;

         }

         public <R, P> R accept(TypeVisitor<R, P> v, P p) {

             return v.visitNoType(this, p);

         }

     }

     public static class TypeVar extends Type implements TypeVariable {

         /** The upper bound of this type variable; set from outside.

          *  Must be nonempty once it is set.

          *  For a bound, `bound' is the bound type itself.

          *  Multiple bounds are expressed as a single class type which has the

          *  individual bounds as superclass, respectively interfaces.

          *  The class type then has as `tsym' a compiler generated class `c',

          *  which has a flag COMPOUND and whose owner is the type variable

          *  itself. Furthermore, the erasure_field of the class

          *  points to the first class or interface bound.

          */

         public Type bound = null;

         /** The lower bound of this type variable.

          *  TypeVars don't normally have a lower bound, so it is normally set

          *  to syms.botType.

          *  Subtypes, such as CapturedType, may provide a different value.

          */

         public Type lower;

         public TypeVar(Name name, Symbol owner, Type lower) {

             super(null);

             tsym = new TypeVariableSymbol(0, name, this, owner);

             this.lower = lower;

         }

         public TypeVar(TypeSymbol tsym, Type bound, Type lower) {

             super(tsym);

             this.bound = bound;

             this.lower = lower;

         }

         @Override

         public TypeTag getTag() {

             return TYPEVAR;

         }

         @Override

         public <R,S> R accept(Type.Visitor<R,S> v, S s) {

             return v.visitTypeVar(this, s);

         }

         @Override

         public Type getUpperBound() {

             if ((bound == null || bound.hasTag(NONE)) && this != tsym.type) {

                 bound = tsym.type.getUpperBound();

             }

             return bound;

         }

         int rank_field = -1;

         @Override

         public Type getLowerBound() {

             return lower;

         }

         public TypeKind getKind() {

             return TypeKind.TYPEVAR;

         }

         public boolean isCaptured() {

             return false;

         }

         @Override

         public boolean isReference() {

             return true;

         }

         @Override

         public boolean isNullOrReference() {

             return true;

         }

         @Override

         public <R, P> R accept(TypeVisitor<R, P> v, P p) {

             return v.visitTypeVariable(this, p);

         }

     }

     /** A captured type variable comes from wildcards which can have

      *  both upper and lower bound.  CapturedType extends TypeVar with

      *  a lower bound.

      */

     public static class CapturedType extends TypeVar {

         public WildcardType wildcard;

         public CapturedType(Name name,

                             Symbol owner,

                             Type upper,

                             Type lower,

                             WildcardType wildcard) {

             super(name, owner, lower);

             this.lower = Assert.checkNonNull(lower);

             this.bound = upper;

             this.wildcard = wildcard;

         }

         @Override

         public <R,S> R accept(Type.Visitor<R,S> v, S s) {

             return v.visitCapturedType(this, s);

         }

         @Override

         public boolean isCaptured() {

             return true;

         }

         @Override

         public String toString() {

             return "capture#"

                 + (hashCode() & 0xFFFFFFFFL) % Printer.PRIME

                 + " of "

                 + wildcard;

         }

     }

     public static abstract class DelegatedType extends Type {

         public Type qtype;

         public TypeTag tag;

         public DelegatedType(TypeTag tag, Type qtype) {

             super(qtype.tsym);

             this.tag = tag;

             this.qtype = qtype;

         }

         public TypeTag getTag() { return tag; }

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

         public List<Type> getTypeArguments() { return qtype.getTypeArguments(); }

         public Type getEnclosingType() { return qtype.getEnclosingType(); }

         public List<Type> getParameterTypes() { return qtype.getParameterTypes(); }

         public Type getReturnType() { return qtype.getReturnType(); }

         public Type getReceiverType() { return qtype.getReceiverType(); }

         public List<Type> getThrownTypes() { return qtype.getThrownTypes(); }

         public List<Type> allparams() { return qtype.allparams(); }

         public Type getUpperBound() { return qtype.getUpperBound(); }

         public boolean isErroneous() { return qtype.isErroneous(); }

     }

     /**

      * The type of a generic method type. It consists of a method type and

      * a list of method type-parameters that are used within the method

      * type.

      */

     public static class ForAll extends DelegatedType implements ExecutableType {

         public List<Type> tvars;

         public ForAll(List<Type> tvars, Type qtype) {

             super(FORALL, (MethodType)qtype);

             this.tvars = tvars;

         }

         @Override

         public <R,S> R accept(Type.Visitor<R,S> v, S s) {

             return v.visitForAll(this, s);

         }

         public String toString() {

             return "<" + tvars + ">" + qtype;

         }

         public List<Type> getTypeArguments()   { return tvars; }

         public boolean isErroneous()  {

             return qtype.isErroneous();

         }

         public Type map(Mapping f) {

             return f.apply(qtype);

         }

         public boolean contains(Type elem) {

             return qtype.contains(elem);

         }

         public MethodType asMethodType() {

             return (MethodType)qtype;

         }

         public void complete() {

             for (List<Type> l = tvars; l.nonEmpty(); l = l.tail) {

                 ((TypeVar)l.head).bound.complete();

             }

             qtype.complete();

         }

         public List<TypeVar> getTypeVariables() {

             return List.convert(TypeVar.class, getTypeArguments());

         }

         public TypeKind getKind() {

             return TypeKind.EXECUTABLE;

         }

         public <R, P> R accept(TypeVisitor<R, P> v, P p) {

             return v.visitExecutable(this, p);

         }

     }

     /** A class for inference variables, for use during method/diamond type

      *  inference. An inference variable has upper/lower bounds and a set

      *  of equality constraints. Such bounds are set during subtyping, type-containment,

      *  type-equality checks, when the types being tested contain inference variables.

      *  A change listener can be attached to an inference variable, to receive notifications

      *  whenever the bounds of an inference variable change.

      */

     public static class UndetVar extends DelegatedType {

         /** Inference variable change listener. The listener method is called

          *  whenever a change to the inference variable's bounds occurs

          */

         public interface UndetVarListener {

             /** called when some inference variable bounds (of given kinds ibs) change */

             void varChanged(UndetVar uv, Set<InferenceBound> ibs);

         }

         /**

          * Inference variable bound kinds

          */

         public enum InferenceBound {

             UPPER {

                 public InferenceBound complement() { return LOWER; }

             },

              /** lower bounds */

             LOWER {

                 public InferenceBound complement() { return UPPER; }

             },

              /** equality constraints */

             EQ {

                 public InferenceBound complement() { return EQ; }

             };

             public abstract InferenceBound complement();

         }

         /** inference variable bounds */

         protected Map<InferenceBound, List<Type>> bounds;

         /** inference variable's inferred type (set from Infer.java) */

         public Type inst = null;

         /** number of declared (upper) bounds */

         public int declaredCount;

         /** inference variable's change listener */

         public UndetVarListener listener = null;

         @Override

         public <R,S> R accept(Type.Visitor<R,S> v, S s) {

             return v.visitUndetVar(this, s);

         }

         public UndetVar(TypeVar origin, Types types) {

             super(UNDETVAR, origin);

             bounds = new EnumMap<InferenceBound, List<Type>>(InferenceBound.class);

             List<Type> declaredBounds = types.getBounds(origin);

             declaredCount = declaredBounds.length();

             bounds.put(InferenceBound.UPPER, declaredBounds);

             bounds.put(InferenceBound.LOWER, List.<Type>nil());

             bounds.put(InferenceBound.EQ, List.<Type>nil());

         }

         public String toString() {

             return (inst == null) ? qtype + "?" : inst.toString();

         }

         public String debugString() {

             String result = "inference var = " + qtype + "\n";

             if (inst != null) {

                 result += "inst = " + inst + '\n';

             }

             for (InferenceBound bound: InferenceBound.values()) {

                 List<Type> aboundList = bounds.get(bound);

                 if (aboundList.size() > 0) {

                     result += bound + " = " + aboundList + '\n';

                 }

             }

             return result;

         }

         @Override

         public boolean isPartial() {

             return true;

         }

         @Override

         public Type baseType() {

             return (inst == null) ? this : inst.baseType();

         }

         /** get all bounds of a given kind */

         public List<Type> getBounds(InferenceBound... ibs) {

             ListBuffer<Type> buf = new ListBuffer<>();

             for (InferenceBound ib : ibs) {

                 buf.appendList(bounds.get(ib));

             }

             return buf.toList();

         }

         /** get the list of declared (upper) bounds */

         public List<Type> getDeclaredBounds() {

             ListBuffer<Type> buf = new ListBuffer<>();

             int count = 0;

             for (Type b : getBounds(InferenceBound.UPPER)) {

                 if (count++ == declaredCount) break;

                 buf.append(b);

             }

             return buf.toList();

         }

         /** internal method used to override an undetvar bounds */

         public void setBounds(InferenceBound ib, List<Type> newBounds) {

             bounds.put(ib, newBounds);

         }

         /** add a bound of a given kind - this might trigger listener notification */

         public final void addBound(InferenceBound ib, Type bound, Types types) {

             addBound(ib, bound, types, false);

         }

         protected void addBound(InferenceBound ib, Type bound, Types types, boolean update) {

             Type bound2 = toTypeVarMap.apply(bound).baseType();

             List<Type> prevBounds = bounds.get(ib);

             for (Type b : prevBounds) {

                 //check for redundancy - use strict version of isSameType on tvars

                 //(as the standard version will lead to false positives w.r.t. clones ivars)

                 if (types.isSameType(b, bound2, true) || bound == qtype) return;

             }

             bounds.put(ib, prevBounds.prepend(bound2));

             notifyChange(EnumSet.of(ib));

         }

         //where

             Type.Mapping toTypeVarMap = new Mapping("toTypeVarMap") {

                 @Override

                 public Type apply(Type t) {

                     if (t.hasTag(UNDETVAR)) {

                         UndetVar uv = (UndetVar)t;

                         return uv.inst != null ? uv.inst : uv.qtype;

                     } else {

                         return t.map(this);

                     }

                 }

             };

         /** replace types in all bounds - this might trigger listener notification */

         public void substBounds(List<Type> from, List<Type> to, Types types) {

             List<Type> instVars = from.diff(to);

             //if set of instantiated ivars is empty, there's nothing to do!

             if (instVars.isEmpty()) return;

             final EnumSet<InferenceBound> boundsChanged = EnumSet.noneOf(InferenceBound.class);

             UndetVarListener prevListener = listener;

             try {

                 //setup new listener for keeping track of changed bounds

                 listener = new UndetVarListener() {

                     public void varChanged(UndetVar uv, Set<InferenceBound> ibs) {

                         boundsChanged.addAll(ibs);

                     }

                 };

                 for (Map.Entry<InferenceBound, List<Type>> _entry : bounds.entrySet()) {

                     InferenceBound ib = _entry.getKey();

                     List<Type> prevBounds = _entry.getValue();

                     ListBuffer<Type> newBounds = new ListBuffer<>();

                     ListBuffer<Type> deps = new ListBuffer<>();

                     //step 1 - re-add bounds that are not dependent on ivars

                     for (Type t : prevBounds) {

                         if (!t.containsAny(instVars)) {

                             newBounds.append(t);

                         } else {

                             deps.append(t);

                         }

                     }

                     //step 2 - replace bounds

                     bounds.put(ib, newBounds.toList());

                     //step 3 - for each dependency, add new replaced bound

                     for (Type dep : deps) {

                         addBound(ib, types.subst(dep, from, to), types, true);

                     }

                 }

             } finally {

                 listener = prevListener;

                 if (!boundsChanged.isEmpty()) {

                     notifyChange(boundsChanged);

                 }

             }

         }

         private void notifyChange(EnumSet<InferenceBound> ibs) {

             if (listener != null) {

                 listener.varChanged(this, ibs);

             }

         }

         public boolean isCaptured() {

             return false;

         }

     }

     /**

      * This class is used to represent synthetic captured inference variables

      * that can be generated during nested generic method calls. The only difference

      * between these inference variables and ordinary ones is that captured inference

      * variables cannot get new bounds through incorporation.

      */

     public static class CapturedUndetVar extends UndetVar {

         public CapturedUndetVar(CapturedType origin, Types types) {

             super(origin, types);

             if (!origin.lower.hasTag(BOT)) {

                 bounds.put(InferenceBound.LOWER, List.of(origin.lower));

             }

         }

         @Override

         public void addBound(InferenceBound ib, Type bound, Types types, boolean update) {

             if (update) {

                 //only change bounds if request comes from substBounds

                 super.addBound(ib, bound, types, update);

             }

         }

         @Override

         public boolean isCaptured() {

             return true;

         }

     }

     /** Represents NONE.

      */

     public static class JCNoType extends Type implements NoType {

         public JCNoType() {

             super(null);

         }

         @Override

         public TypeTag getTag() {

             return NONE;

         }

         @Override

         public TypeKind getKind() {

             return TypeKind.NONE;

         }

         @Override

         public <R, P> R accept(TypeVisitor<R, P> v, P p) {

             return v.visitNoType(this, p);

         }

         @Override

         public boolean isCompound() { return false; }

     }

     /** Represents VOID.

      */

     public static class JCVoidType extends Type implements NoType {

         public JCVoidType() {

             super(null);

         }

         @Override

         public TypeTag getTag() {

             return VOID;

         }

         @Override

         public TypeKind getKind() {

             return TypeKind.VOID;

         }

         @Override

         public boolean isCompound() { return false; }

         @Override

         public <R, P> R accept(TypeVisitor<R, P> v, P p) {

             return v.visitNoType(this, p);

         }

         @Override

         public boolean isPrimitiveOrVoid() {

             return true;

         }

     }

     static class BottomType extends Type implements NullType {

         public BottomType() {

             super(null);

         }

         @Override

         public TypeTag getTag() {

             return BOT;

         }

         @Override

         public TypeKind getKind() {

             return TypeKind.NULL;

         }

         @Override

         public boolean isCompound() { return false; }

         @Override

         public <R, P> R accept(TypeVisitor<R, P> v, P p) {

             return v.visitNull(this, p);

         }

         @Override

         public Type constType(Object value) {

             return this;

         }

         @Override

         public String stringValue() {

             return "null";

         }

         @Override

         public boolean isNullOrReference() {

             return true;

         }

     }

     public static class ErrorType extends ClassType

             implements javax.lang.model.type.ErrorType {

         private Type originalType = null;

         public ErrorType(Type originalType, TypeSymbol tsym) {

             super(noType, List.<Type>nil(), null);

             this.tsym = tsym;

             this.originalType = (originalType == null ? noType : originalType);

         }

         public ErrorType(ClassSymbol c, Type originalType) {

             this(originalType, c);

             c.type = this;

             c.kind = ERR;

             c.members_field = new Scope.ErrorScope(c);

         }

         @Override

         public TypeTag getTag() {

             return ERROR;

         }

         @Override

         public boolean isPartial() {

             return true;

         }

         @Override

         public boolean isReference() {

             return true;

         }

         @Override

         public boolean isNullOrReference() {

             return true;

         }

         public ErrorType(Name name, TypeSymbol container, Type originalType) {

             this(new ClassSymbol(PUBLIC|STATIC|ACYCLIC, name, null, container), originalType);

         }

         @Override

         public <R,S> R accept(Type.Visitor<R,S> v, S s) {

             return v.visitErrorType(this, s);

         }

         public Type constType(Object constValue) { return this; }

         public Type getEnclosingType()           { return this; }

         public Type getReturnType()              { return this; }

         public Type asSub(Symbol sym)            { return this; }

         public Type map(Mapping f)               { return this; }

         public boolean isGenType(Type t)         { return true; }

         public boolean isErroneous()             { return true; }

         public boolean isCompound()              { return false; }

         public boolean isInterface()             { return false; }

         public List<Type> allparams()            { return List.nil(); }

         public List<Type> getTypeArguments()     { return List.nil(); }

         public TypeKind getKind() {

             return TypeKind.ERROR;

         }

         public Type getOriginalType() {

             return originalType;

         }

         public <R, P> R accept(TypeVisitor<R, P> v, P p) {

             return v.visitError(this, p);

         }

     }

     public static class AnnotatedType extends Type

             implements

                 javax.lang.model.type.ArrayType,

                 javax.lang.model.type.DeclaredType,

                 javax.lang.model.type.PrimitiveType,

                 javax.lang.model.type.TypeVariable,

                 javax.lang.model.type.WildcardType {

         /** The type annotations on this type.

          */

         private List<Attribute.TypeCompound> typeAnnotations;

         /** The underlying type that is annotated.

          */

         private Type underlyingType;

         protected AnnotatedType(List<Attribute.TypeCompound> typeAnnotations,

                 Type underlyingType) {

             super(underlyingType.tsym);

             this.typeAnnotations = typeAnnotations;

             this.underlyingType = underlyingType;

             Assert.check(typeAnnotations != null && typeAnnotations.nonEmpty(),

                     "Can't create AnnotatedType without annotations: " + underlyingType);

             Assert.check(!underlyingType.isAnnotated(),

                     "Can't annotate already annotated type: " + underlyingType +

                     "; adding: " + typeAnnotations);

         }

         @Override

         public TypeTag getTag() {

             return underlyingType.getTag();

         }

         @Override

         public boolean isAnnotated() {

             return true;

         }

         @Override

         public List<Attribute.TypeCompound> getAnnotationMirrors() {

             return typeAnnotations;

         }

         @Override

         public TypeKind getKind() {

             return underlyingType.getKind();

         }

         @Override

         public Type unannotatedType() {

             return underlyingType;

         }

         @Override

         public <R,S> R accept(Type.Visitor<R,S> v, S s) {

             return v.visitAnnotatedType(this, s);

         }

         @Override

         public <R, P> R accept(TypeVisitor<R, P> v, P p) {

             return underlyingType.accept(v, p);

         }

         @Override

         public Type map(Mapping f) {

             underlyingType.map(f);

             return this;

         }

         @Override

         public Type constType(Object constValue) { return underlyingType.constType(constValue); }

         @Override

         public Type getEnclosingType()           { return underlyingType.getEnclosingType(); }

         @Override

         public Type getReturnType()              { return underlyingType.getReturnType(); }

         @Override

         public List<Type> getTypeArguments()     { return underlyingType.getTypeArguments(); }

         @Override

         public List<Type> getParameterTypes()    { return underlyingType.getParameterTypes(); }

         @Override

         public Type getReceiverType()            { return underlyingType.getReceiverType(); }

         @Override

         public List<Type> getThrownTypes()       { return underlyingType.getThrownTypes(); }

         @Override

         public Type getUpperBound()              { return underlyingType.getUpperBound(); }

         @Override

         public Type getLowerBound()              { return underlyingType.getLowerBound(); }

         @Override

         public boolean isErroneous()             { return underlyingType.isErroneous(); }

         @Override

         public boolean isCompound()              { return underlyingType.isCompound(); }

         @Override

         public boolean isInterface()             { return underlyingType.isInterface(); }

         @Override

         public List<Type> allparams()            { return underlyingType.allparams(); }

         @Override

         public boolean isPrimitive()             { return underlyingType.isPrimitive(); }

         @Override

         public boolean isPrimitiveOrVoid()       { return underlyingType.isPrimitiveOrVoid(); }

         @Override

         public boolean isNumeric()               { return underlyingType.isNumeric(); }

         @Override

         public boolean isReference()             { return underlyingType.isReference(); }

         @Override

         public boolean isNullOrReference()       { return underlyingType.isNullOrReference(); }

         @Override

         public boolean isPartial()               { return underlyingType.isPartial(); }

         @Override

         public boolean isParameterized()         { return underlyingType.isParameterized(); }

         @Override

         public boolean isRaw()                   { return underlyingType.isRaw(); }

         @Override

         public boolean isFinal()                 { return underlyingType.isFinal(); }

         @Override

         public boolean isSuperBound()            { return underlyingType.isSuperBound(); }

         @Override

         public boolean isExtendsBound()          { return underlyingType.isExtendsBound(); }

         @Override

         public boolean isUnbound()               { return underlyingType.isUnbound(); }

         @Override

         public String toString() {

             // This method is only used for internal debugging output.

             // See

             // com.sun.tools.javac.code.Printer.visitAnnotatedType(AnnotatedType, Locale)

             // for the user-visible logic.

             if (typeAnnotations != null &&

                     !typeAnnotations.isEmpty()) {

                 return "(" + typeAnnotations.toString() + " :: " + underlyingType.toString() + ")";

             } else {

                 return "({} :: " + underlyingType.toString() +")";

             }

         }

         @Override

         public boolean contains(Type t)          { return underlyingType.contains(t); }

         @Override

         public Type withTypeVar(Type t) {

             // Don't create a new AnnotatedType, as 'this' will

             // get its annotations set later.

             underlyingType = underlyingType.withTypeVar(t);

             return this;

         }

         // TODO: attach annotations?

         @Override

         public TypeSymbol asElement()            { return underlyingType.asElement(); }

         // TODO: attach annotations?

         @Override

         public MethodType asMethodType()         { return underlyingType.asMethodType(); }

         @Override

         public void complete()                   { underlyingType.complete(); }

         @Override

         public TypeMirror getComponentType()     { return ((ArrayType)underlyingType).getComponentType(); }

         // The result is an ArrayType, but only in the model sense, not the Type sense.

         public Type makeVarargs() {

             return ((ArrayType) underlyingType).makeVarargs().annotatedType(typeAnnotations);

         }

         @Override

         public TypeMirror getExtendsBound()      { return ((WildcardType)underlyingType).getExtendsBound(); }

         @Override

         public TypeMirror getSuperBound()        { return ((WildcardType)underlyingType).getSuperBound(); }

     }

     public static class UnknownType extends Type {

         public UnknownType() {

             super(null);

         }

         @Override

         public TypeTag getTag() {

             return UNKNOWN;

         }

         @Override

         public <R, P> R accept(TypeVisitor<R, P> v, P p) {

             return v.visitUnknown(this, p);

         }

         @Override

         public boolean isPartial() {

             return true;

         }

     }

     /**

      * A visitor for types.  A visitor is used to implement operations

      * (or relations) on types.  Most common operations on types are

      * binary relations and this interface is designed for binary

      * relations, that is, operations of the form

      * Type × S → R.

      * <!-- In plain text: Type x S -> R -->

      *

      * @param <R> the return type of the operation implemented by this

      * visitor; use Void if no return type is needed.

      * @param <S> the type of the second argument (the first being the

      * type itself) of the operation implemented by this visitor; use

      * Void if a second argument is not needed.

      */

     public interface Visitor<R,S> {

         R visitClassType(ClassType t, S s);

         R visitWildcardType(WildcardType t, S s);

         R visitArrayType(ArrayType t, S s);

         R visitMethodType(MethodType t, S s);

         R visitPackageType(PackageType t, S s);

         R visitTypeVar(TypeVar t, S s);

         R visitCapturedType(CapturedType t, S s);

         R visitForAll(ForAll t, S s);

         R visitUndetVar(UndetVar t, S s);

         R visitErrorType(ErrorType t, S s);

         R visitAnnotatedType(AnnotatedType t, S s);

         R visitType(Type t, S s);

     }

 }