HeapDumper.java

package org.springsource.ide.eclipse.commons.tests.util;
import javax.management.MBeanServer;

import java.io.File;
import java.lang.management.ManagementFactory;

import com.sun.management.HotSpotDiagnosticMXBean;

@SuppressWarnings("restriction")
public class HeapDumper {
    // This is the name of the HotSpot Diagnostic MBean
    private static final String HOTSPOT_BEAN_NAME =
         "com.sun.management:type=HotSpotDiagnostic";

    // field to store the hotspot diagnostic MBean
    @SuppressWarnings("restriction")
	private static volatile HotSpotDiagnosticMXBean hotspotMBean;

     /**
      * Call this method from your application whenever you
      * want to dump the heap snapshot into a file.
      *
      * @param fileName name of the heap dump file
      * @param live flag that tells whether to dump
      *             only the live objects
      */
    public static void dumpHeap(String fileName, boolean live) {
    	File file = new File(fileName);
    	if (file.exists()) {
    		file.delete();
    	}
    	System.out.println("Dumping heap to: "+file.getAbsolutePath());
        // initialize hotspot diagnostic MBean
        initHotspotMBean();
        try {
            hotspotMBean.dumpHeap(file.getAbsolutePath(), live);
        } catch (RuntimeException re) {
            throw re;
        } catch (Exception exp) {
            throw new RuntimeException(exp);
        }
    }

    // initialize the hotspot diagnostic MBean field
    private static void initHotspotMBean() {
        if (hotspotMBean == null) {
            synchronized (HeapDumper.class) {
                if (hotspotMBean == null) {
                    hotspotMBean = getHotspotMBean();
                }
            }
        }
    }

    // get the hotspot diagnostic MBean from the
    // platform MBean server
    private static HotSpotDiagnosticMXBean getHotspotMBean() {
        try {
            MBeanServer server = ManagementFactory.getPlatformMBeanServer();
            HotSpotDiagnosticMXBean bean =
                ManagementFactory.newPlatformMXBeanProxy(server,
                HOTSPOT_BEAN_NAME, HotSpotDiagnosticMXBean.class);
            return bean;
        } catch (RuntimeException re) {
            throw re;
        } catch (Exception exp) {
            throw new RuntimeException(exp);
        }
    }

    public static void main(String[] args) {
        // default heap dump file name
        String fileName = "heap.bin";
        // by default dump only the live objects
        boolean live = true;

        // simple command line options
        switch (args.length) {
            case 2:
                live = args[1].equals("true");
            case 1:
                fileName = args[0];
        }

        // dump the heap
        dumpHeap(fileName, live);
    }
}