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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.NodeNotExistsException;
import org.jboss.cache.NodeSPI;
import org.jboss.cache.commands.legacy.ReversibleCommand;
import org.jboss.cache.commands.write.MoveCommand;
/**
* A version of {@link org.jboss.cache.commands.write.MoveCommand} 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 PessMoveCommand extends MoveCommand implements ReversibleCommand
{
public PessMoveCommand()
{
}
public PessMoveCommand(Fqn from, Fqn to)
{
super(from, to);
}
/**
* Moves a node, from <tt>fqn</tt> to <tt>to</tt>, and returns null.
*
* @param ctx invocation context
* @return null
*/
@Override
public Object perform(InvocationContext ctx)
{
move(fqn, to, false, ctx);
return null;
}
private void adjustFqn(NodeSPI node, Fqn newBase)
{
Fqn newFqn = Fqn.fromRelativeElements(newBase, node.getFqn().getLastElement());
node.setFqn(newFqn);
}
private void move(Fqn toMoveFqn, Fqn newParentFqn, boolean skipNotifications, InvocationContext ctx)
{
// the actual move algorithm.
// ctx *could* be null if this is a rollback!!! Sucks big time.
NodeSPI newParent = ctx == null ? dataContainer.peek(newParentFqn) : ctx.lookUpNode(newParentFqn);
if (newParent == null || newParent.isDeleted())
{
throw new NodeNotExistsException("New parent node " + newParentFqn + " does not exist when attempting to move node!!");
}
// ctx *could* be null if this is a rollback!!! Sucks big time.
NodeSPI node = ctx == null ? dataContainer.peek(toMoveFqn) : ctx.lookUpNode(toMoveFqn);
if (node == null || node.isDeleted())
{
throw new NodeNotExistsException("Node " + toMoveFqn + " does not exist when attempting to move node!!");
}
if (trace) log.trace("Moving " + fqn + " to sit under " + to);
NodeSPI oldParent = node.getParentDirect();
Object nodeName = toMoveFqn.getLastElement();
// now that we have the parent and target nodes:
// first correct the pointers at the pruning point
oldParent.removeChildDirect(nodeName);
newParent.addChild(nodeName, node);
// parent pointer is calculated on the fly using Fqns.
// notify
if (!skipNotifications)
notifier.notifyNodeMoved(toMoveFqn, Fqn.fromRelativeElements(newParentFqn, toMoveFqn.getLastElement()), true, ctx);
// now adjust Fqns of node and all children.
adjustFqn(node, newParent.getFqn());
if (!skipNotifications)
notifier.notifyNodeMoved(toMoveFqn, Fqn.fromRelativeElements(newParentFqn, toMoveFqn.getLastElement()), false, ctx);
}
public void rollback()
{
move(Fqn.fromRelativeElements(to, fqn.getLastElement()), fqn.getParent(), true, null);
}
}