/*
* JBoss, Home of Professional Open Source.
* Copyright 2000 - 2008, Red Hat Middleware LLC, and individual contributors
* as indicated by the @author tags. See the copyright.txt file 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.cache.commands.legacy.write;
import org.jboss.cache.CacheException;
import org.jboss.cache.Fqn;
import org.jboss.cache.InvocationContext;
import org.jboss.cache.NodeSPI;
import org.jboss.cache.commands.legacy.ReversibleCommand;
import org.jboss.cache.commands.write.PutForExternalReadCommand;
import org.jboss.cache.transaction.GlobalTransaction;
/**
* A version of {@link org.jboss.cache.commands.write.PutForExternalReadCommand} which can be rolled back, for use with
* pessimistic locking where changes are made directly on the data structures and may need to be reversed.
*
* @author Manik Surtani (<a href="mailto:manik AT jboss DOT org">manik AT jboss DOT org</a>)
* @since 3.0
* @deprecated will be removed along with optimistic and pessimistic locking.
*/
@Deprecated
public class PessPutForExternalReadCommand extends PutForExternalReadCommand implements ReversibleCommand
{
protected Object oldValue;
public PessPutForExternalReadCommand(GlobalTransaction gtx, Fqn fqn, Object key, Object value)
{
super(gtx, fqn, key, value);
}
public PessPutForExternalReadCommand()
{
}
@Override
public Object perform(InvocationContext ctx)
{
oldValue = super.perform(ctx);
return oldValue;
}
public void rollback()
{
NodeSPI n = dataContainer.peek(fqn, false, false);
if (n == null) throw new CacheException("node " + fqn + " not found for rollback!");
if (oldValue == null)
{
n.removeDirect(key);
}
else
{
n.putDirect(key, oldValue);
}
}
}