/*
* 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.write;
import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;
import org.jboss.cache.CacheSPI;
import org.jboss.cache.DataContainer;
import org.jboss.cache.Fqn;
import org.jboss.cache.InvocationContext;
import org.jboss.cache.NodeSPI;
import org.jboss.cache.commands.Visitor;
import org.jboss.cache.commands.read.AbstractDataCommand;
import org.jboss.cache.notifications.Notifier;
/**
* Removes a node's content from memory - never removes the node.
* It also clenups data for resident nodes - which are not being touched by eviction.
*
* @author Mircea.Markus@jboss.com
* @since 2.2
*/
public class InvalidateCommand extends AbstractDataCommand
{
public static final int METHOD_ID = 47;
private static final Log log = LogFactory.getLog(InvalidateCommand.class);
private static final boolean trace = log.isTraceEnabled();
/* dependencies*/
protected CacheSPI spi;
protected Notifier notifier;
public InvalidateCommand(Fqn fqn)
{
this.fqn = fqn;
}
public InvalidateCommand()
{
}
public void initialize(CacheSPI cacheSpi, DataContainer dataContainer, Notifier notifier)
{
this.spi = cacheSpi;
this.dataContainer = dataContainer;
this.notifier = notifier;
}
/**
* Performs an invalidation on a specified node
*
* @param ctx invocation context
* @return null
*/
public Object perform(InvocationContext ctx)
{
NodeSPI node = enforceNodeLoading();
if (trace) log.trace("Invalidating fqn:" + fqn);
if (node == null)
{
return null;
}
evictNode(fqn, ctx);
invalidateNode(node);
return null;
}
boolean evictNode(Fqn fqn, InvocationContext ctx)
{
notifier.notifyNodeInvalidated(fqn, true, ctx);
try
{
return dataContainer.evict(fqn);
}
finally
{
notifier.notifyNodeInvalidated(fqn, false, ctx);
}
}
/**
* //TODO: 2.2.0: rather than using CacheSPI this should use peek(). The other interceptors should obtain locks and load nodes if necessary for this InvalidateCommand.
* //Even better - this can be handles in the interceptors before call interceptor
*/
protected NodeSPI enforceNodeLoading()
{
return spi.getNode(fqn);
}
/**
* mark the node to be removed (and all children) as invalid so anyone holding a direct reference to it will
* be aware that it is no longer valid.
*/
protected void invalidateNode(NodeSPI node)
{
node.setValid(false, true);
// root nodes can never be invalid
if (fqn.isRoot()) node.setValid(true, false); // non-recursive.
}
public Object acceptVisitor(InvocationContext ctx, Visitor visitor) throws Throwable
{
return visitor.visitInvalidateCommand(ctx, this);
}
public int getCommandId()
{
return METHOD_ID;
}
@Override
public String toString()
{
return "InvalidateCommand{" +
"fqn=" + fqn +
'}';
}
@Override
public Object[] getParameters()
{
return new Object[]{fqn};
}
@Override
public void setParameters(int commandId, Object[] args)
{
fqn = (Fqn) args[0];
}
void setFqn(Fqn newFqn)
{
this.fqn = newFqn;
}
}