psiprobe.beans.JvmMemoryInfoAccessorBean.java Source code

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Here is the source code for 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 psiprobe.beans;

import org.apache.commons.modeler.Registry;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;

import psiprobe.model.jmx.MemoryPool;
import psiprobe.tools.JmxTools;

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;

/**
 * The Class JvmMemoryInfoAccessorBean.
 */
public class JvmMemoryInfoAccessorBean {

    /** The logger. */
    private static final Logger logger = LoggerFactory.getLogger(JvmMemoryInfoAccessorBean.class);

    /**
     * Gets the pools.
     *
     * @return the pools
     * @throws Exception the exception
     */
    public List<MemoryPool> getPools() throws Exception {

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

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

        for (ObjectInstance oi : memoryOPools) {
            ObjectName objName = oi.getObjectName();
            MemoryPool memoryPool = new MemoryPool();
            memoryPool.setName(JmxTools.getStringAttr(mbeanServer, objName, "Name"));
            memoryPool.setType(JmxTools.getStringAttr(mbeanServer, objName, "Type"));

            CompositeDataSupport cd = (CompositeDataSupport) mbeanServer.getAttribute(objName, "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? {} 'Usage' attribute is NULL!", objName);
            }

            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;

    }
}