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* 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.interceptors;
import org.jboss.cache.Fqn;
import org.jboss.cache.InvocationContext;
import org.jboss.cache.NodeSPI;
import org.jboss.cache.commands.write.EvictCommand;
import org.jboss.cache.factories.annotations.Inject;
import org.jboss.cache.interceptors.base.JmxStatsCommandInterceptor;
import org.jboss.cache.jmx.annotations.ManagedAttribute;
import org.jboss.cache.jmx.annotations.ManagedOperation;
import org.jboss.cache.loader.CacheLoader;
import org.jboss.cache.loader.CacheLoaderManager;
import org.jboss.cache.notifications.Notifier;
import java.util.Collections;
import java.util.HashMap;
import java.util.Map;
import java.util.concurrent.atomic.AtomicLong;
/**
* Writes evicted nodes back to the store on the way in through the
* CacheLoader, either before each method call (no TXs), or at TX commit.
*
* @author <a href="mailto:{hmesha@novell.com}">{Hany Mesha}</a>
* @version $Id: PassivationInterceptor.java 6776 2008-09-22 17:35:46Z manik.surtani@jboss.com $
*/
public class PassivationInterceptor extends JmxStatsCommandInterceptor
{
private final AtomicLong passivations = new AtomicLong(0);
protected CacheLoader loader;
private Notifier notifier;
@Inject
public void setDependencies(Notifier notifier, CacheLoaderManager loaderManager)
{
this.notifier = notifier;
this.loader = loaderManager.getCacheLoader();
}
/**
* Notifies the cache instance listeners that the evicted node is about to
* be passivated and stores the evicted node and its attributes back to the
* store using the CacheLoader.
*/
@Override
public Object visitEvictFqnCommand(InvocationContext ctx, EvictCommand command) throws Throwable
{
if (command.isRecursive())
{
for (Fqn f : command.getNodesToEvict()) passivate(ctx, f);
}
else
{
passivate(ctx, command.getFqn());
}
return invokeNextInterceptor(ctx, command);
}
protected void passivate(InvocationContext ctx, Fqn fqn) throws Throwable
{
try
{
// evict method local doesn't hold attributes therefore we have
// to get them manually
Map attributes = getNodeAttributes(ctx, fqn);
// notify listeners that this node is about to be passivated
notifier.notifyNodePassivated(fqn, true, attributes, ctx);
if (trace) log.trace("Passivating " + fqn);
loader.put(fqn, attributes);
notifier.notifyNodePassivated(fqn, false, Collections.emptyMap(), ctx);
if (getStatisticsEnabled()) passivations.getAndIncrement();
}
catch (NodeNotLoadedException e)
{
if (trace)
{
log.trace("Node " + fqn + " not loaded in memory; passivation skipped");
}
}
}
/**
* Returns attributes for a node.
*/
private Map getNodeAttributes(InvocationContext ctx, Fqn fqn) throws NodeNotLoadedException
{
if (fqn == null)
{
throw new NodeNotLoadedException();
}
NodeSPI n = ctx.lookUpNode(fqn);
if (n != null)
{
return n.getDataDirect();
}
else
{
throw new NodeNotLoadedException();
}
}
private static class NodeNotLoadedException extends Exception
{
/**
* The serialVersionUID
*/
private static final long serialVersionUID = -4078972305344328905L;
}
@ManagedOperation
public void resetStatistics()
{
passivations.set(0);
}
@ManagedOperation
public Map<String, Object> dumpStatistics()
{
Map<String, Object> retval = new HashMap<String, Object>();
retval.put("Passivations", passivations.get());
return retval;
}
@ManagedAttribute(description = "number of cache node passivations")
public long getPassivations()
{
return passivations.get();
}
}