/*
* JBoss, Home of Professional Open Source.
* Copyright 2006, 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.ha.singleton;
import java.security.InvalidParameterException;
import javax.management.InstanceNotFoundException;
import javax.management.JMException;
import javax.management.MBeanException;
import javax.management.ObjectName;
import javax.management.ReflectionException;
/**
* A clustered singleton service that calls a configurable
* method on a target mbean, whenever the current node becomes
* the master. Correspondigly, it calls a configurable method
* on the target mbean, whenever the current node resigns from
* being the master.
*
* Optional string arguments may be passed to those methods.
*
* The prevailing usage of this MBean is to deploy on the
* master node the content of the deploy-hasingleton directory.
*
* @author <a href="mailto:ivelin@apache.org">Ivelin Ivanov</a>
* @author <a href="mailto:scott.stark@jboss.org">Scott Stark</a>
* @author <a href="mailto:mr@gedoplan.de">Marcus Redeker</a>
* @author <a href="mailto:dimitris@jboss.org">Dimitris Andreadis</a>
* @version $Revision: 57188 $
*/
public class HASingletonController extends HASingletonSupport
implements HASingletonControllerMBean
{
// Private Data --------------------------------------------------
private ObjectName mSingletonMBean;
private String mSingletonMBeanStartMethod = "startSingleton";
private String mSingletonMBeanStopMethod = "stopSingleton";
private String mSingletonMBeanStartMethodArgument;
private String mSingletonMBeanStopMethodArgument;
private static final Object[] NO_ARGS = new Object[0];
private static final String[] NO_TYPES = new String[0];
// Constructors --------------------------------------------------
/**
* Default CTOR
*/
public HASingletonController()
{
// empty
}
// Attributes ----------------------------------------------------
public ObjectName getTargetName()
{
return mSingletonMBean;
}
public void setTargetName(ObjectName targetObjectName)
{
this.mSingletonMBean = targetObjectName;
}
public String getTargetStartMethod()
{
return mSingletonMBeanStartMethod;
}
public void setTargetStartMethod(String targetStartMethod)
throws InvalidParameterException
{
if (targetStartMethod != null)
mSingletonMBeanStartMethod = targetStartMethod;
}
public String getTargetStopMethod()
{
return mSingletonMBeanStopMethod;
}
public void setTargetStopMethod(String targetStopMethod)
throws InvalidParameterException
{
if (targetStopMethod != null)
mSingletonMBeanStopMethod = targetStopMethod;
}
public String getTargetStartMethodArgument()
{
return mSingletonMBeanStartMethodArgument ;
}
public void setTargetStartMethodArgument(String targetStartMethodArgument)
{
mSingletonMBeanStartMethodArgument = targetStartMethodArgument;
}
public String getTargetStopMethodArgument()
{
return mSingletonMBeanStopMethodArgument ;
}
public void setTargetStopMethodArgument(String targetStopMethodArgument)
{
mSingletonMBeanStopMethodArgument = targetStopMethodArgument;
}
// HASingleton implementation ------------------------------------
/**
* Call the target start method
*
* @see org.jboss.ha.singleton.HASingletonSupport#startSingleton()
*/
public void startSingleton()
{
super.startSingleton();
try
{
invokeSingletonMBeanMethod(
mSingletonMBean,
mSingletonMBeanStartMethod,
mSingletonMBeanStartMethodArgument
);
}
catch (JMException jme)
{
log.error("Controlled Singleton MBean failed to become master", jme);
}
}
/**
* Call the target stop method
*
* @see org.jboss.ha.singleton.HASingletonSupport#stopSingleton()
*/
public void stopSingleton()
{
super.stopSingleton();
try
{
invokeSingletonMBeanMethod(
mSingletonMBean,
mSingletonMBeanStopMethod,
mSingletonMBeanStopMethodArgument
);
}
catch (JMException jme)
{
log.error("Controlled Singleton MBean failed to resign from master position", jme);
}
}
// Protected -----------------------------------------------------
protected Object invokeSingletonMBeanMethod(ObjectName target,
String operationName, Object param)
throws InstanceNotFoundException, MBeanException, ReflectionException
{
if (target != null && operationName != null)
{
Object[] params;
String[] signature;
if (param != null)
{
params = new Object[] { param };
signature = new String[] { param.getClass().getName() };
log.debug("Calling operation: " + operationName +
"(" + param + "), on target: '" + target + "'");
}
else
{
params = NO_ARGS;
signature = NO_TYPES;
log.debug("Calling operation: " + operationName +
"(), on target: '" + target + "'");
}
return server.invoke(target, operationName, params, signature);
}
else
{
log.debug("No configured target mbean or operation to call");
return null;
}
}
}
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