/*
* Copyright 1999,2004 The Apache Software Foundation.
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package org.apache.catalina.cluster.session;
import javax.management.MBeanServer;
import javax.management.MBeanServerFactory;
import javax.management.MalformedObjectNameException;
import javax.management.ObjectName;
import javax.management.modelmbean.ModelMBean;
import org.apache.catalina.Lifecycle;
import org.apache.catalina.LifecycleEvent;
import org.apache.catalina.LifecycleListener;
import org.apache.catalina.cluster.CatalinaCluster;
import org.apache.catalina.cluster.MessageListener;
import org.apache.catalina.core.StandardHost;
import org.apache.catalina.util.StringManager;
import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;
import org.apache.commons.modeler.ManagedBean;
import org.apache.commons.modeler.Registry;
/**
* Register new JvmRouteSessionIDBinderListener to receive Session ID changes.
*
* add following at your server.xml Host section
*
* <pre>
* <Host >...
* <Listener className="org.apache.catalina.cluster.session.JvmRouteSessionIDBinderLifecycleListener" />
* <Cluster ...>
* </Host>
* </pre>
*
* @author Peter Rossbach
*/
public class JvmRouteSessionIDBinderLifecycleListener implements
LifecycleListener {
private static Log log = LogFactory
.getLog(JvmRouteSessionIDBinderLifecycleListener.class);
/**
* The descriptive information string for this implementation.
*/
private static final String info = "org.apache.catalina.cluster.session.JvmRouteSessionIDBinderLifecycleListener/1.0";
/**
* The string resources for this package.
*/
protected static final StringManager sm = StringManager
.getManager(Constants.Package);
private boolean enabled = true;
private MBeanServer mserver = null;
private Registry registry = null;
private MessageListener sessionMoverListener;
/*
* start and stop cluster
*
* @see org.apache.catalina.LifecycleListener#lifecycleEvent(org.apache.catalina.LifecycleEvent)
*/
public void lifecycleEvent(LifecycleEvent event) {
if (enabled && event.getSource() instanceof StandardHost) {
if (Lifecycle.AFTER_START_EVENT.equals(event.getType())) {
if (log.isDebugEnabled())
log.debug(sm.getString("jvmRoute.listener.started"));
startSessionIDListener((StandardHost) event.getSource());
} else if (Lifecycle.BEFORE_STOP_EVENT.equals(event.getType())) {
if (log.isDebugEnabled())
log.debug(sm.getString("jvmRoute.listener.stopped"));
stopSessionIDListener((StandardHost) event.getSource());
}
}
}
/**
* stop sessionID binder at cluster
*
* @param host
* clustered host
*/
protected void stopSessionIDListener(StandardHost host) {
if (sessionMoverListener != null) {
CatalinaCluster cluster = (CatalinaCluster) host.getCluster();
cluster.removeClusterListener(sessionMoverListener);
if (mserver != null) {
try {
ObjectName objectName = getObjectName(host);
mserver.unregisterMBean(objectName);
} catch (Exception e) {
log.error(e);
}
}
}
}
/**
* @param host
* @return
* @throws MalformedObjectNameException
*/
protected ObjectName getObjectName(StandardHost host) throws MalformedObjectNameException {
ObjectName objectName = new ObjectName(
host.getDomain()
+ ":type=Listener,name=JvmRouteSessionIDBinderListener,host=" + host.getName());
return objectName;
}
/**
* start sessionID mover at cluster
*
* @param host
* clustered host
*/
protected void startSessionIDListener(StandardHost host) {
try {
ObjectName objectName = null;
getMBeanServer();
objectName = getObjectName(host);
if (mserver.isRegistered(objectName)) {
if (log.isInfoEnabled())
log.info(sm.getString("jvmRoute.run.already"));
return;
}
sessionMoverListener = new JvmRouteSessionIDBinderListener();
mserver.registerMBean(getManagedBean(sessionMoverListener),
objectName);
CatalinaCluster cluster = (CatalinaCluster) host.getCluster();
sessionMoverListener.setCluster(cluster);
((JvmRouteSessionIDBinderListener) sessionMoverListener).start();
} catch (Exception ex) {
log.error(ex.getMessage(), ex);
}
}
protected MBeanServer getMBeanServer() throws Exception {
if (mserver == null) {
if (MBeanServerFactory.findMBeanServer(null).size() > 0) {
mserver = (MBeanServer) MBeanServerFactory
.findMBeanServer(null).get(0);
} else {
mserver = MBeanServerFactory.createMBeanServer();
}
registry = Registry.getRegistry(null, null);
registry.loadMetadata(this.getClass().getResourceAsStream(
"mbeans-descriptors.xml"));
}
return (mserver);
}
/**
* Returns the ModelMBean
*
* @param object
* The Object to get the ModelMBean for
* @return The ModelMBean
* @throws Exception
* If an error occurs this constructors throws this exception
*/
protected ModelMBean getManagedBean(Object object) throws Exception {
ModelMBean mbean = null;
if (registry != null) {
ManagedBean managedBean = registry.findManagedBean(object
.getClass().getName());
mbean = managedBean.createMBean(object);
}
return mbean;
}
/**
* @return Returns the enabled.
*/
public boolean isEnabled() {
return enabled;
}
/**
* @param enabled
* The enabled to set.
*/
public void setEnabled(boolean enabled) {
this.enabled = enabled;
}
/**
* Return descriptive information about this Listener implementation and the
* corresponding version number, in the format
* <code><description>/<version></code>.
*/
public String getInfo() {
return (info);
}
}