/*
* JBoss, Home of Professional Open Source
* Copyright 2005, JBoss Inc., and individual contributors as indicated
* by the @authors tag. See the copyright.txt in the distribution for a
* full listing of individual contributors.
*
* This is free software; you can redistribute it and/or modify it
* under the terms of the GNU Lesser General Public License as
* published by the Free Software Foundation; either version 2.1 of
* the License, or (at your option) any later version.
*
* This software 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
* Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public
* License along with this software; if not, write to the Free
* Software Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA
* 02110-1301 USA, or see the FSF site: http://www.fsf.org.
*/
package org.jboss.ejb.plugins.cmp.jdbc.bridge;

import java.io.Serializable;
import java.io.ObjectStreamException;

/**
 * Type safe enumeration of message objects.
 * Used by optmistic lock to lock fields and its values dependeding
 * on the strategy used.
 *
 * @author <a href="mailto:aloubyansky@hotmail.com">Alex Loubyansky</a>
 * @version $Revision$
 */
public final class CMPMessage
   implements Serializable
{
   static final long serialVersionUID = -5463196805602475992L;

   // Constants ------------------------------------------------
   private static int nextOrdinal = 0;
   private static final CMPMessage[] VALUES = new CMPMessage[5];

   public static final CMPMessage CHANGED = new CMPMessage("CHANGED");
   public static final CMPMessage ACCESSED = new CMPMessage("ACCESSED");

   private final transient String name;
   private final int ordinal;

   // Constructor ----------------------------------------------
   private CMPMessage(String name)
   {
      this.name = name;
      this.ordinal = nextOrdinal++;
      VALUES[ordinal] = this;
   }

   // Public ---------------------------------------------------
   public String toString()
   {
      return name;
   }

   // Package --------------------------------------------------
   Object readResolve()
      throws ObjectStreamException
   {
      return VALUES[ordinal];
   }
}
