/*

 * Copyright (c) 2001, 2013, 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.

 *

 * 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 sun.jvm.hotspot.utilities;

import sun.jvm.hotspot.runtime.BasicType;

public class ConstantTag {

  // These replicated from the VM to save space

  private static final int JVM_CONSTANT_Utf8                    = 1;

  private static final int JVM_CONSTANT_Unicode                 = 2; // unused

  private static final int JVM_CONSTANT_Integer                 = 3;

  private static final int JVM_CONSTANT_Float                   = 4;

  private static final int JVM_CONSTANT_Long                    = 5;

  private static final int JVM_CONSTANT_Double                  = 6;

  private static final int JVM_CONSTANT_Class                   = 7;

  private static final int JVM_CONSTANT_String                  = 8;

  private static final int JVM_CONSTANT_Fieldref                = 9;

  private static final int JVM_CONSTANT_Methodref               = 10;

  private static final int JVM_CONSTANT_InterfaceMethodref      = 11;

  private static final int JVM_CONSTANT_NameAndType             = 12;

  private static final int JVM_CONSTANT_MethodHandle            = 15;  // JSR 292

  private static final int JVM_CONSTANT_MethodType              = 16;  // JSR 292

  private static final int JVM_CONSTANT_InvokeDynamic           = 18;  // JSR 292

  private static final int JVM_CONSTANT_Invalid                 = 0;   // For bad value initialization

  private static final int JVM_CONSTANT_UnresolvedClass         = 100; // Temporary tag until actual use

  private static final int JVM_CONSTANT_ClassIndex              = 101; // Temporary tag while constructing constant pool

  private static final int JVM_CONSTANT_StringIndex             = 102; // Temporary tag while constructing constant pool

  private static final int JVM_CONSTANT_UnresolvedClassInError  = 103; // Resolution failed

  private static final int JVM_CONSTANT_MethodHandleInError     = 104; // Error tag due to resolution error

  private static final int JVM_CONSTANT_MethodTypeInError       = 105; // Error tag due to resolution error

  // JVM_CONSTANT_MethodHandle subtypes //FIXME: connect these to data structure

  private static int JVM_REF_getField                = 1;

  private static int JVM_REF_getStatic               = 2;

  private static int JVM_REF_putField                = 3;

  private static int JVM_REF_putStatic               = 4;

  private static int JVM_REF_invokeVirtual           = 5;

  private static int JVM_REF_invokeStatic            = 6;

  private static int JVM_REF_invokeSpecial           = 7;

  private static int JVM_REF_newInvokeSpecial        = 8;

  private static int JVM_REF_invokeInterface         = 9;

  private byte tag;

  public ConstantTag(byte tag) {

    this.tag = tag;

  }

  public int value() { return tag; }

  public boolean isKlass()            { return tag == JVM_CONSTANT_Class; }

  public boolean isField ()           { return tag == JVM_CONSTANT_Fieldref; }

  public boolean isMethod()           { return tag == JVM_CONSTANT_Methodref; }

  public boolean isInterfaceMethod()  { return tag == JVM_CONSTANT_InterfaceMethodref; }

  public boolean isString()           { return tag == JVM_CONSTANT_String; }

  public boolean isInt()              { return tag == JVM_CONSTANT_Integer; }

  public boolean isFloat()            { return tag == JVM_CONSTANT_Float; }

  public boolean isLong()             { return tag == JVM_CONSTANT_Long; }

  public boolean isDouble()           { return tag == JVM_CONSTANT_Double; }

  public boolean isNameAndType()      { return tag == JVM_CONSTANT_NameAndType; }

  public boolean isUtf8()             { return tag == JVM_CONSTANT_Utf8; }

  public boolean isMethodHandle()     { return tag == JVM_CONSTANT_MethodHandle; }

  public boolean isMethodType()       { return tag == JVM_CONSTANT_MethodType; }

  public boolean isInvokeDynamic()    { return tag == JVM_CONSTANT_InvokeDynamic; }

  public boolean isInvalid()          { return tag == JVM_CONSTANT_Invalid; }

  public boolean isUnresolvedKlass()  {

    return tag == JVM_CONSTANT_UnresolvedClass || tag == JVM_CONSTANT_UnresolvedClassInError;

  }

  public boolean isUnresolveKlassInError()  { return tag == JVM_CONSTANT_UnresolvedClassInError; }

  public boolean isKlassIndex()             { return tag == JVM_CONSTANT_ClassIndex; }

  public boolean isStringIndex()            { return tag == JVM_CONSTANT_StringIndex; }

  public boolean isKlassReference()   { return isKlassIndex() || isUnresolvedKlass(); }

  public boolean isFieldOrMethod()    { return isField() || isMethod() || isInterfaceMethod(); }

  public boolean isSymbol()           { return isUtf8(); }

  public BasicType basicType() {

    switch (tag) {

    case JVM_CONSTANT_Integer :

      return BasicType.T_INT;

    case JVM_CONSTANT_Float :

      return BasicType.T_FLOAT;

    case JVM_CONSTANT_Long :

      return BasicType.T_LONG;

    case JVM_CONSTANT_Double :

      return BasicType.T_DOUBLE;

    case JVM_CONSTANT_Class :

    case JVM_CONSTANT_String :

    case JVM_CONSTANT_UnresolvedClass :

    case JVM_CONSTANT_UnresolvedClassInError :

    case JVM_CONSTANT_MethodHandleInError :

    case JVM_CONSTANT_MethodTypeInError :

    case JVM_CONSTANT_ClassIndex :

    case JVM_CONSTANT_StringIndex :

    case JVM_CONSTANT_MethodHandle :

    case JVM_CONSTANT_MethodType :

      return BasicType.T_OBJECT;

    default:

      throw new InternalError("unexpected tag: " + tag);

    }

  }

  public String toString() {

    return "ConstantTag:" + Integer.toString(tag);

}

}