com.googlecode.psiprobe.beans.JvmMemoryInfoAccessorBean.java Source code

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Here is the source code for com.googlecode.psiprobe.beans.JvmMemoryInfoAccessorBean.java

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/*
 * Licensed under the GPL License.  You may not use this file except in
 * compliance with the License.  You may obtain a copy of the License at
 *
 *     http://www.gnu.org/licenses/old-licenses/gpl-2.0.html
 *
 * THIS PACKAGE IS PROVIDED "AS IS" AND WITHOUT ANY EXPRESS OR IMPLIED
 * WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED WARRANTIES OF
 * MERCHANTIBILITY AND FITNESS FOR A PARTICULAR PURPOSE.
 */
package com.googlecode.psiprobe.beans;

import com.googlecode.psiprobe.model.jmx.MemoryPool;
import com.googlecode.psiprobe.tools.JmxTools;
import java.util.Iterator;
import java.util.LinkedList;
import java.util.List;
import java.util.Set;
import javax.management.MBeanServer;
import javax.management.ObjectInstance;
import javax.management.ObjectName;
import javax.management.openmbean.CompositeDataSupport;
import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;
import org.apache.commons.modeler.Registry;

/**
 * 
 * @author Vlad Ilyushchenko
 */
public class JvmMemoryInfoAccessorBean {

    private Log logger = LogFactory.getLog(this.getClass());

    public List getPools() throws Exception {

        List memoryPools = new LinkedList();
        MBeanServer mBeanServer = new Registry().getMBeanServer();
        Set memoryOPools = mBeanServer.queryMBeans(new ObjectName("java.lang:type=MemoryPool,*"), null);

        //
        // totals
        //
        long totalInit = 0;
        long totalMax = 0;
        long totalUsed = 0;
        long totalCommitted = 0;

        for (Iterator it = memoryOPools.iterator(); it.hasNext();) {
            ObjectInstance oi = (ObjectInstance) it.next();
            ObjectName oName = oi.getObjectName();
            MemoryPool memoryPool = new MemoryPool();
            memoryPool.setName(JmxTools.getStringAttr(mBeanServer, oName, "Name"));
            memoryPool.setType(JmxTools.getStringAttr(mBeanServer, oName, "Type"));

            CompositeDataSupport cd = (CompositeDataSupport) mBeanServer.getAttribute(oName, "Usage");
            //
            // It seems that "Usage" attribute of one of the pools may turn into null intermittently. We better have a
            // dip in the graph then an NPE though.
            //
            if (cd != null) {
                memoryPool.setMax(JmxTools.getLongAttr(cd, "max"));
                memoryPool.setUsed(JmxTools.getLongAttr(cd, "used"));
                memoryPool.setInit(JmxTools.getLongAttr(cd, "init"));
                memoryPool.setCommitted(JmxTools.getLongAttr(cd, "committed"));
            } else {
                logger.error("Oops, JVM problem? " + oName.toString() + " \"Usage\" attribute is NULL!");
            }

            totalInit += memoryPool.getInit();
            totalMax += memoryPool.getMax();
            totalUsed += memoryPool.getUsed();
            totalCommitted += memoryPool.getCommitted();

            memoryPools.add(memoryPool);
        }

        if (!memoryPools.isEmpty()) {
            MemoryPool pool = new MemoryPool();
            pool.setName("Total");
            pool.setType("TOTAL");
            pool.setInit(totalInit);
            pool.setUsed(totalUsed);
            pool.setMax(totalMax);
            pool.setCommitted(totalCommitted);
            memoryPools.add(pool);
        }

        return memoryPools;

    }
}