/*
* JBoss, Home of Professional Open Source.
* Copyright 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.varia.counter;
import java.text.DecimalFormat;
import java.util.HashMap;
import java.util.Iterator;
import java.util.Vector;
import javax.naming.InitialContext;
import javax.naming.NamingException;
import javax.naming.Reference;
import javax.naming.StringRefAddr;
import org.jboss.system.ServiceMBeanSupport;
import org.jboss.naming.NonSerializableFactory;
/**
* A service offering accumulator style counters to help in diagnosing
* performance issues.
*
* @jmx:mbean extends="org.jboss.system.ServiceMBean"
*
* @author <a href="mailto:danch@nvisia.com">Dan Christopherson</href>
* @version $Revision: 81038 $
*/
public class CounterService
extends ServiceMBeanSupport
implements CounterServiceMBean
{
public static final String JNDI_NAME = "java:/CounterService";
private HashMap counterMap = new HashMap();
/**
* accumulate a count into a named counter. will initialize the named
* counter if neccessary.
*/
public void accumulate(String counterName, long add)
{
Counter counter = null;
synchronized (counterMap)
{
counter = (Counter)counterMap.get(counterName);
if (counter == null)
{
counter = new Counter(counterName);
counterMap.put(counterName, counter);
}
}
counter.addToCount(add);
}
protected void startService() throws Exception
{
InitialContext ctx = new InitialContext();
//bind myself into JNDI, at java:/CounterService
NonSerializableFactory.bind(JNDI_NAME, this);
StringRefAddr addr = new StringRefAddr("nns", JNDI_NAME);
Reference ref = new Reference(this.getClass().getName(), addr, NonSerializableFactory.class.getName(), null);
ctx.bind(JNDI_NAME, ref);
}
protected void stopService() throws Exception
{
InitialContext ctx = new InitialContext();
ctx.unbind(JNDI_NAME);
NonSerializableFactory.unbind(JNDI_NAME);
}
/**
* @jmx:managed-operation
*/
public String list()
{
DecimalFormat format = new DecimalFormat("####0.0000");
String retVal = "";
Iterator keys = counterMap.keySet().iterator();
while (keys.hasNext())
{
String key = (String)keys.next();
Counter counter = (Counter)counterMap.get(key);
long total = 0;
int entries = 0;
synchronized (counter)
{//so we dont catch half of it.
total = counter.getCount();
entries = counter.getEntries();
}
double avg = ((double)total)/((double)entries);
String descrip = key+": total="+total+" on "+entries+"entries for "+
"an average of "+format.format(avg)+"<br>\n";
retVal += descrip;
}
return retVal;
}
private static class Counter
{
private String name;
private long count=0;
private int entries=0;
public Counter(String n)
{
name = n;
}
public String getName()
{
return name;
}
public synchronized long getCount()
{
return count;
}
public synchronized int getEntries()
{
return entries;
}
public synchronized void addToCount(long add)
{
count += add;
entries++;
}
}
}