/*
* 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.read;
import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;
import org.jboss.cache.Fqn;
import org.jboss.cache.InvocationContext;
import org.jboss.cache.NodeSPI;
import org.jboss.cache.commands.Visitor;
/**
* Implements functionality defined by {@link org.jboss.cache.Cache#getNode(org.jboss.cache.Fqn)}
* <p/>
* This is the equivalent of the old MethodCallDefinitions.getNodeMethodLocal method call from 2.1.x.
* <p/>
*
* @author Mircea.Markus@jboss.com
* @since 2.2.0
*/
public class GetNodeCommand extends AbstractDataCommand
{
public static final int METHOD_ID = 31;
private static final Log log = LogFactory.getLog(GetNodeCommand.class);
private static final boolean trace = log.isTraceEnabled();
public GetNodeCommand(Fqn fqn)
{
this.fqn = fqn;
}
public GetNodeCommand()
{
}
/**
* Retrieves a {@link org.jboss.cache.Node} referenced by the specified Fqn.
*
* @param ctx invocation context
* @return a Node, or null if the Fqn refers to a node that does not exist.
*/
public Object perform(InvocationContext ctx)
{
NodeSPI node = ctx.lookUpNode(fqn);
if (node != null && node.isDeleted())
{
if (trace)
log.trace("Node of type [" + node.getClass().getSimpleName() + "] found but marked as deleted in current scope. Returning null.");
return null;
}
if (trace) log.trace("Found node, returning " + node);
return node;
}
public Object acceptVisitor(InvocationContext ctx, Visitor visitor) throws Throwable
{
return visitor.visitGetNodeCommand(ctx, this);
}
public int getCommandId()
{
return METHOD_ID;
}
}