import java.util.Collections;

import java.util.HashSet;

import java.util.Set;

import java.util.concurrent.CountDownLatch;

import java.util.concurrent.TimeUnit;

import java.util.concurrent.atomic.AtomicBoolean;

import javax.management.MBeanServerConnection;

import javax.management.Notification;

import javax.management.NotificationListener;

import javax.management.ObjectName;

import javax.management.remote.JMXConnectionNotification;

import javax.management.remote.JMXConnector;

import javax.management.remote.JMXConnectorFactory;

import javax.management.remote.JMXServiceURL;

public class Client {

    public static void run(String url) throws Exception {

        final int notifEmittedCnt = 10;

        final CountDownLatch counter = new CountDownLatch(notifEmittedCnt);

        final Set<Long> seqSet = Collections.synchronizedSet(new HashSet<Long>());

        final AtomicBoolean duplNotification = new AtomicBoolean();

        JMXServiceURL serverUrl = new JMXServiceURL(url);

        ObjectName name = new ObjectName("test", "foo", "bar");

        JMXConnector jmxConnector = JMXConnectorFactory.connect(serverUrl);

        System.out.println("client connected");

        jmxConnector.addConnectionNotificationListener(new NotificationListener() {

            @Override

            public void handleNotification(Notification notification, Object handback) {

                System.out.println("connection notification: " + notification);

                if (!seqSet.add(notification.getSequenceNumber())) {

                    duplNotification.set(true);

                }

                if (notification.getType().equals(JMXConnectionNotification.NOTIFS_LOST)) {

                    long lostNotifs = ((Long)((JMXConnectionNotification)notification).getUserData()).longValue();

                    for(int i=0;i<lostNotifs;i++) {

                        counter.countDown();

                    }

                }

            }

        }, null, null);

        MBeanServerConnection jmxServer = jmxConnector.getMBeanServerConnection();

        jmxServer.addNotificationListener(name, new NotificationListener() {

            @Override

            public void handleNotification(Notification notification, Object handback) {

                System.out.println("client got: " + notification);

                if (!seqSet.add(notification.getSequenceNumber())) {

                    duplNotification.set(true);

                }

                counter.countDown();

            }

        }, null, null);

        System.out.println("client invoking foo (" + notifEmittedCnt + " times)");

        for(int i=0;i<notifEmittedCnt;i++) {

            System.out.print(".");

            jmxServer.invoke(name, "foo", new Object[]{}, new String[]{});

        }

        System.out.println();

        try {

            System.out.println("waiting for " + notifEmittedCnt + " notifications to arrive");

            if (!counter.await(30, TimeUnit.SECONDS)) {

                throw new InterruptedException();

            }

            if (duplNotification.get()) {

                System.out.println("ERROR: received duplicated notifications");

                throw new Error("received duplicated notifications");

            }

            System.out.println("\nshutting down client");

        } catch (InterruptedException e) {

            System.out.println("ERROR: notification processing thread interrupted");

            throw new Error("notification thread interrupted unexpectedly");

        }

    }

}