/** Constructs a PrintGCStat object to monitor a remote JVM. */
public PrintGCStat(MBeanServerConnection server) throws IOException {
// Create the platform mxbean proxies
this.rmbean = newPlatformMXBeanProxy(server, RUNTIME_MXBEAN_NAME, RuntimeMXBean.class);
this.mmbean = newPlatformMXBeanProxy(server, MEMORY_MXBEAN_NAME, MemoryMXBean.class);
ObjectName poolName = null;
ObjectName gcName = null;
try {
poolName = new ObjectName(MEMORY_POOL_MXBEAN_DOMAIN_TYPE + ",*");
gcName = new ObjectName(GARBAGE_COLLECTOR_MXBEAN_DOMAIN_TYPE + ",*");
} catch (MalformedObjectNameException e) {
// should not reach here
assert (false);
}
Set<ObjectName> mbeans = server.queryNames(poolName, null);
if (mbeans != null) {
pools = new ArrayList<MemoryPoolMXBean>();
for (ObjectName objName : mbeans) {
MemoryPoolMXBean p =
newPlatformMXBeanProxy(server, objName.getCanonicalName(), MemoryPoolMXBean.class);
pools.add(p);
}
}
mbeans = server.queryNames(gcName, null);
if (mbeans != null) {
gcmbeans = new ArrayList<GarbageCollectorMXBean>();
for (ObjectName objName : mbeans) {
GarbageCollectorMXBean gc =
newPlatformMXBeanProxy(
server, objName.getCanonicalName(), GarbageCollectorMXBean.class);
gcmbeans.add(gc);
}
}
}
@SuppressWarnings("unchecked")
protected Object newProxyInstance(
ObjectName objectName, Class interfaceClass, boolean notificationBroadcaster)
throws Exception {
Object jmx_proxy =
MBeanServerInvocationHandler.newProxyInstance(
getMBeanServerConnection(), objectName, interfaceClass, notificationBroadcaster);
return addGetId(interfaceClass, jmx_proxy, objectName.getCanonicalName());
}
public static void main(String[] args) throws Exception {
MBeanServer mbs = ManagementFactory.getPlatformMBeanServer();
final Boolean isNotificationSupported =
AccessController.doPrivileged(
new PrivilegedAction<Boolean>() {
public Boolean run() {
try {
Class cl = Class.forName("sun.management.VMManagementImpl");
Field f = cl.getDeclaredField("gcNotificationSupport");
f.setAccessible(true);
return f.getBoolean(null);
} catch (ClassNotFoundException e) {
return false;
} catch (NoSuchFieldException e) {
return false;
} catch (IllegalAccessException e) {
return false;
}
}
});
if (!isNotificationSupported) {
System.out.println("GC Notification not supported by the JVM, test skipped");
return;
}
final ObjectName gcMXBeanPattern = new ObjectName("java.lang:type=GarbageCollector,*");
Set<ObjectName> names = mbs.queryNames(gcMXBeanPattern, null);
if (names.isEmpty()) throw new Exception("Test incorrect: no GC MXBeans");
number = names.size();
for (ObjectName n : names) {
if (mbs.isInstanceOf(n, "javax.management.NotificationEmitter")) {
listenerInvoked.put(n.getCanonicalName(), null);
GcListener listener = new GcListener();
mbs.addNotificationListener(n, listener, null, null);
}
}
// Invocation of System.gc() to trigger major GC
System.gc();
// Allocation of many short living and small objects to trigger minor GC
Object data[] = new Object[32];
for (int i = 0; i < 100000000; i++) {
data[i % 32] = new int[8];
}
int wakeup = 0;
synchronized (synchronizer) {
while (count != number) {
synchronizer.wait(10000);
wakeup++;
if (wakeup > 10) break;
}
}
for (GarbageCollectionNotificationInfo notif : listenerInvoked.values()) {
checkGarbageCollectionNotificationInfoContent(notif);
}
System.out.println("Test passed");
}
/**
* Return an end user readable representation of the underlying MBean
*
* @return the user readable description
*/
public String toString() {
StringBuilder buf = new StringBuilder();
buf.append("MBean Name:").append("\n ").append(name.getCanonicalName()).append("\n ");
if (!listAttributeDescriptions().isEmpty()) {
buf.append("\nAttributes:");
for (String attrDesc : listAttributeDescriptions()) {
buf.append("\n ").append(attrDesc);
}
}
if (!listOperationDescriptions().isEmpty()) {
buf.append("\nOperations:");
for (String attrDesc : listOperationDescriptions()) {
buf.append("\n ").append(attrDesc);
}
}
return buf.toString();
}
static void MonitorGC(long h) {
handle = h;
List<GarbageCollectorMXBean> gcbeans =
java.lang.management.ManagementFactory.getGarbageCollectorMXBeans();
MBeanServer server = ManagementFactory.getPlatformMBeanServer();
try {
ObjectName gcName =
new ObjectName(ManagementFactory.GARBAGE_COLLECTOR_MXBEAN_DOMAIN_TYPE + ",*");
for (ObjectName name : server.queryNames(gcName, null)) {
GarbageCollectorMXBean gc =
ManagementFactory.newPlatformMXBeanProxy(
server, name.getCanonicalName(), GarbageCollectorMXBean.class);
gcbeans.add(gc);
NotificationEmitter emitter = (NotificationEmitter) gc;
NotificationListener listener =
new NotificationListener() {
@Override
public void handleNotification(Notification notification, Object handback) {
if (notification
.getType()
.equals(GarbageCollectionNotificationInfo.GARBAGE_COLLECTION_NOTIFICATION)) {
CompositeData ndata = (CompositeData) notification.getUserData();
GarbageCollectionNotificationInfo info =
GarbageCollectionNotificationInfo.from(ndata);
boolean major = "end of major GC".equals(info.getGcAction());
long free = Runtime.getRuntime().freeMemory();
long total = Runtime.getRuntime().totalMemory();
long qty = (15 * total) - (free * 100);
if (qty > 0) {
NotifyOSv(handle, qty);
}
}
}
};
emitter.addNotificationListener(listener, null, null);
}
} catch (Exception e) {
throw new RuntimeException(e);
}
}
