/*
* Client.java - JMX client that interacts with the JMX agent. It gets
* attributes and performs operations on the Hello MBean and the QueueSampler
* MXBean example. It also listens for Hello MBean notifications.
*/
package com.example;
import java.io.IOException;
import java.util.Arrays;
import java.util.Iterator;
import java.util.Set;
import java.util.TreeSet;
import javax.management.AttributeChangeNotification;
import javax.management.JMX;
import javax.management.MBeanServerConnection;
import javax.management.Notification;
import javax.management.NotificationEmitter;
import javax.management.NotificationListener;
import javax.management.ObjectName;
import javax.management.remote.JMXConnector;
import javax.management.remote.JMXConnectorFactory;
import javax.management.remote.JMXServiceURL;
public class Client {
/**
* Inner class that will handle the notifications.
*/
public static class ClientListener implements NotificationListener {
public void handleNotification(Notification notification,
Object handback) {
echo("\nReceived notification:");
echo("\tClassName: " + notification.getClass().getName());
echo("\tSource: " + notification.getSource());
echo("\tType: " + notification.getType());
echo("\tMessage: " + notification.getMessage());
if (notification instanceof AttributeChangeNotification) {
AttributeChangeNotification acn =
(AttributeChangeNotification) notification;
echo("\tAttributeName: " + acn.getAttributeName());
echo("\tAttributeType: " + acn.getAttributeType());
echo("\tNewValue: " + acn.getNewValue());
echo("\tOldValue: " + acn.getOldValue());
}
}
}
/* For simplicity, we declare "throws Exception".
Real programs will usually want finer-grained exception handling. */
public static void main(String[] args) throws Exception {
// Create an RMI connector client and
// connect it to the RMI connector server
//
echo("\nCreate an RMI connector client and " +
"connect it to the RMI connector server");
JMXServiceURL url =
new JMXServiceURL("service:jmx:rmi:///jndi/rmi://:9999/jmxrmi");
JMXConnector jmxc = JMXConnectorFactory.connect(url, null);
// Create listener
//
ClientListener listener = new ClientListener();
// Get an MBeanServerConnection
//
echo("\nGet an MBeanServerConnection");
MBeanServerConnection mbsc = jmxc.getMBeanServerConnection();
waitForEnterPressed();
// Get domains from MBeanServer
//
echo("\nDomains:");
String domains[] = mbsc.getDomains();
Arrays.sort(domains);
for (String domain : domains) {
echo("\tDomain = " + domain);
}
waitForEnterPressed();
// Get MBeanServer's default domain
//
echo("\nMBeanServer default domain = " + mbsc.getDefaultDomain());
// Get MBean count
//
echo("\nMBean count = " + mbsc.getMBeanCount());
// Query MBean names
//
echo("\nQuery MBeanServer MBeans:");
Set<ObjectName> names =
new TreeSet<ObjectName>(mbsc.queryNames(null, null));
for (ObjectName name : names) {
echo("\tObjectName = " + name);
}
waitForEnterPressed();
// ----------------------
// Manage the Hello MBean
// ----------------------
echo("\n>>> Perform operations on Hello MBean <<<");
// Construct the ObjectName for the Hello MBean
//
ObjectName mbeanName = new ObjectName("com.example:type=Hello");
// Create a dedicated proxy for the MBean instead of
// going directly through the MBean server connection
//
HelloMBean mbeanProxy =
JMX.newMBeanProxy(mbsc, mbeanName, HelloMBean.class, true);
// Add notification listener on Hello MBean
//
echo("\nAdd notification listener...");
mbsc.addNotificationListener(mbeanName, listener, null, null);
// Get CacheSize attribute in Hello MBean
//
echo("\nCacheSize = " + mbeanProxy.getCacheSize());
// Set CacheSize attribute in Hello MBean
// Calling "reset" makes the Hello MBean emit a
// notification that will be received by the registered
// ClientListener.
//
mbeanProxy.setCacheSize(150);
// Sleep for 2 seconds to have time to receive the notification
//
echo("\nWaiting for notification...");
sleep(2000);
// Get CacheSize attribute in Hello MBean
//
echo("\nCacheSize = " + mbeanProxy.getCacheSize());
// Invoke "sayHello" in Hello MBean
//
echo("\nInvoke sayHello() in Hello MBean...");
mbeanProxy.sayHello();
// Invoke "add" in Hello MBean
//
echo("\nInvoke add(2, 3) in Hello MBean...");
echo("\nadd(2, 3) = " + mbeanProxy.add(2, 3));
waitForEnterPressed();
// ------------------------------
// Manage the QueueSampler MXBean
// ------------------------------
echo("\n>>> Perform operations on QueueSampler MXBean <<<");
// Construct the ObjectName for the QueueSampler MXBean
//
ObjectName mxbeanName =
new ObjectName("com.example:type=QueueSampler");
// Create a dedicated proxy for the MXBean instead of
// going directly through the MBean server connection
//
QueueSamplerMXBean mxbeanProxy =
JMX.newMXBeanProxy(mbsc, mxbeanName, QueueSamplerMXBean.class);
// Get QueueSample attribute in QueueSampler MXBean
//
QueueSample queue1 = mxbeanProxy.getQueueSample();
echo("\nQueueSample.Date = " + queue1.getDate());
echo("QueueSample.Head = " + queue1.getHead());
echo("QueueSample.Size = " + queue1.getSize());
// Invoke "clearQueue" in QueueSampler MXBean
//
echo("\nInvoke clearQueue() in QueueSampler MXBean...");
mxbeanProxy.clearQueue();
// Get QueueSample attribute in QueueSampler MXBean
//
QueueSample queue2 = mxbeanProxy.getQueueSample();
echo("\nQueueSample.Date = " + queue2.getDate());
echo("QueueSample.Head = " + queue2.getHead());
echo("QueueSample.Size = " + queue2.getSize());
waitForEnterPressed();
// Close MBeanServer connection
//
echo("\nClose the connection to the server");
jmxc.close();
echo("\nBye! Bye!");
}
static void echo(String msg) {
System.out.println(msg);
}
private static void sleep(int millis) {
try {
Thread.sleep(millis);
} catch (InterruptedException e) {
e.printStackTrace();
}
}
private static void waitForEnterPressed() {
try {
echo("\nPress <Enter> to continue...");
System.in.read();
} catch (IOException e) {
e.printStackTrace();
}
}
}