com.snowstore.mercury.core.metric.SystemPublicMetrics.java Source code

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Here is the source code for com.snowstore.mercury.core.metric.SystemPublicMetrics.java

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/*
 * Copyright 2012-2015 the original author or authors.
 *
 * 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 com.snowstore.mercury.core.metric;

import java.lang.management.ClassLoadingMXBean;
import java.lang.management.GarbageCollectorMXBean;
import java.lang.management.ManagementFactory;
import java.lang.management.MemoryUsage;
import java.lang.management.ThreadMXBean;
import java.util.Collection;
import java.util.LinkedHashSet;
import java.util.List;

import org.apache.commons.lang3.StringUtils;

/**
 * A {@link PublicMetrics} implementation that provides various system-related
 * metrics.
 * 
 * @author Dave Syer
 * @author Christian Dupuis
 * @author Stephane Nicoll
 * @author Johannes Stelzer
 * @since 1.2.0
 */
public class SystemPublicMetrics implements PublicMetrics {

    private long timestamp;

    public SystemPublicMetrics() {
        this.timestamp = System.currentTimeMillis();
    }

    @Override
    public Collection<Metric<?>> metrics() {
        Collection<Metric<?>> result = new LinkedHashSet<Metric<?>>();
        addBasicMetrics(result);
        addManagementMetrics(result);
        return result;
    }

    /**
     * Add basic system metrics.
     * 
     * @param result
     *            the result
     */
    protected void addBasicMetrics(Collection<Metric<?>> result) {
        // NOTE: ManagementFactory must not be used here since it fails on GAE
        result.add(new Metric<Long>("mem", Runtime.getRuntime().totalMemory() / 1024));
        result.add(new Metric<Long>("mem.free", Runtime.getRuntime().freeMemory() / 1024));
        result.add(new Metric<Integer>("processors", Runtime.getRuntime().availableProcessors()));
        result.add(new Metric<Long>("instance.uptime", System.currentTimeMillis() - this.timestamp));
    }

    /**
     * Add metrics from ManagementFactory if possible. Note that
     * ManagementFactory is not available on Google App Engine.
     */
    private void addManagementMetrics(Collection<Metric<?>> result) {
        try {
            // Add JVM up time in ms
            result.add(new Metric<Long>("uptime", ManagementFactory.getRuntimeMXBean().getUptime()));
            result.add(new Metric<Double>("systemload.average",
                    ManagementFactory.getOperatingSystemMXBean().getSystemLoadAverage()));
            addHeapMetrics(result);
            addNoHeapMetrics(result);
            addThreadMetrics(result);
            addClassLoadingMetrics(result);
            addGarbageCollectionMetrics(result);
        } catch (NoClassDefFoundError ex) {
            // Expected on Google App Engine
        }
    }

    /**
     * Add JVM heap metrics.
     * 
     * @param result
     *            the result
     */
    protected void addHeapMetrics(Collection<Metric<?>> result) {
        MemoryUsage memoryUsage = ManagementFactory.getMemoryMXBean().getHeapMemoryUsage();
        result.add(new Metric<Long>("heap.committed", memoryUsage.getCommitted() / 1024));
        result.add(new Metric<Long>("heap.init", memoryUsage.getInit() / 1024));
        result.add(new Metric<Long>("heap.used", memoryUsage.getUsed() / 1024));
        result.add(new Metric<Long>("heap", memoryUsage.getMax() / 1024));
    }

    /**
     * Add JVM heap metrics.
     * 
     * @param result
     *            the result
     */
    protected void addNoHeapMetrics(Collection<Metric<?>> result) {
        MemoryUsage memoryUsage = ManagementFactory.getMemoryMXBean().getNonHeapMemoryUsage();
        result.add(new Metric<Long>("noheap.committed", memoryUsage.getCommitted() / 1024));
        result.add(new Metric<Long>("noheap.init", memoryUsage.getInit() / 1024));
        result.add(new Metric<Long>("noheap.used", memoryUsage.getUsed() / 1024));
        result.add(new Metric<Long>("noheap", memoryUsage.getMax() / 1024));
    }

    /**
     * Add thread metrics.
     * 
     * @param result
     *            the result
     */
    protected void addThreadMetrics(Collection<Metric<?>> result) {
        ThreadMXBean threadMxBean = ManagementFactory.getThreadMXBean();
        result.add(new Metric<Long>("threads.peak", (long) threadMxBean.getPeakThreadCount()));
        result.add(new Metric<Long>("threads.daemon", (long) threadMxBean.getDaemonThreadCount()));
        result.add(new Metric<Long>("threads", (long) threadMxBean.getThreadCount()));
    }

    /**
     * Add class loading metrics.
     * 
     * @param result
     *            the result
     */
    protected void addClassLoadingMetrics(Collection<Metric<?>> result) {
        ClassLoadingMXBean classLoadingMxBean = ManagementFactory.getClassLoadingMXBean();
        result.add(new Metric<Long>("classes", (long) classLoadingMxBean.getLoadedClassCount()));
        result.add(new Metric<Long>("classes.loaded", classLoadingMxBean.getTotalLoadedClassCount()));
        result.add(new Metric<Long>("classes.unloaded", classLoadingMxBean.getUnloadedClassCount()));
    }

    /**
     * Add garbage collection metrics.
     * 
     * @param result
     *            the result
     */
    protected void addGarbageCollectionMetrics(Collection<Metric<?>> result) {
        List<GarbageCollectorMXBean> garbageCollectorMxBeans = ManagementFactory.getGarbageCollectorMXBeans();
        for (GarbageCollectorMXBean garbageCollectorMXBean : garbageCollectorMxBeans) {
            String name = beautifyGcName(garbageCollectorMXBean.getName());
            result.add(new Metric<Long>("gc." + name + ".count", garbageCollectorMXBean.getCollectionCount()));
            result.add(new Metric<Long>("gc." + name + ".time", garbageCollectorMXBean.getCollectionTime()));
        }
    }

    /**
     * Turn GC names like 'PS Scavenge' or 'PS MarkSweep' into something that is
     * more metrics friendly.
     */
    private String beautifyGcName(String name) {
        return StringUtils.replace(name, " ", "_").toLowerCase();
    }

}