/*
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* 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.Fqn;
import org.jboss.cache.InvocationContext;
import org.jboss.cache.NodeSPI;
import org.jboss.cache.commands.legacy.ReversibleCommand;
import org.jboss.cache.commands.write.ClearDataCommand;
import org.jboss.cache.transaction.GlobalTransaction;
import java.util.HashMap;
/**
* A version of {@link org.jboss.cache.commands.write.ClearDataCommand} 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 PessClearDataCommand extends ClearDataCommand implements ReversibleCommand
{
private HashMap originalData;
public PessClearDataCommand(GlobalTransaction gtx, Fqn fqn)
{
super(gtx, fqn);
}
public PessClearDataCommand()
{
}
@Override
public Object perform(InvocationContext ctx)
{
if (globalTransaction != null)
{
NodeSPI n = ctx.lookUpNode(fqn);
originalData = n == null ? null : new HashMap(n.getDataDirect());
}
return super.perform(ctx);
}
public void rollback()
{
if (trace) log.trace("rollback(" + globalTransaction + ", \"" + fqn + "\", " + originalData + ")");
if (originalData != null && !originalData.isEmpty())
{
NodeSPI nodeSpi = dataContainer.peek(fqn, false, true);
if (nodeSpi == null)
{
if (trace)
log.trace("Not rolling back node clearance for node: " + fqn + " as it does not exist in the cache. " +
"This might be the result of an NoOp clear operation");
return;
}
nodeSpi.putAllDirect(originalData);
}
}
}