/*

 * Copyright 2008 Sun Microsystems, Inc.  All Rights Reserved.

 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.

 *

 * This code is free software; you can redistribute it and/or modify it

 * under the terms of the GNU General Public License version 2 only, as

 * published by the Free Software Foundation.

 *

 * This code is distributed in the hope that it will be useful, but WITHOUT

 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or

 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License

 * version 2 for more details (a copy is included in the LICENSE file that

 * accompanied this code).

 *

 * You should have received a copy of the GNU General Public License version

 * 2 along with this work; if not, write to the Free Software Foundation,

 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.

 *

 * Please contact Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,

 * CA 95054 USA or visit www.sun.com if you need additional information or

 * have any questions.

 */

import java.util.Random;

import java.util.Set;

import javax.management.AttributeChangeNotification;

import javax.management.ListenerNotFoundException;

import javax.management.MBeanAttributeInfo;

import javax.management.MBeanInfo;

import javax.management.MBeanNotificationInfo;

import javax.management.MBeanOperationInfo;

import javax.management.MBeanParameterInfo;

import javax.management.MBeanRegistration;

import javax.management.MBeanServer;

import javax.management.NotCompliantMBeanException;

import javax.management.NotificationBroadcasterSupport;

import javax.management.NotificationEmitter;

import javax.management.NotificationFilter;

import javax.management.NotificationListener;

import javax.management.ObjectName;

import javax.management.StandardMBean;

/**

 * Dynamic MBean based on StandardMBean

 * Class Wombat

 * Wombat Description

 * @author dfuchs

 */

public class Wombat extends StandardMBean

        implements WombatMBean, NotificationEmitter, MBeanRegistration {

    /**

     * Attribute : Caption

     */

    private String caption = "I'm a wombat";

    private final long MAX_SEED = 36000;

    private final long seed;

    private final long period;

    private volatile int mood = 0;

    public int getMood() {

        final long  degree = seed + (System.currentTimeMillis()/period)%MAX_SEED;

        final double angle = ((double)degree)/100;

        mood = (int)(100.0*Math.sin(angle));

        return mood;

    }

    public Wombat() throws NotCompliantMBeanException {

        super(WombatMBean.class);

        final Random r = new Random();

        seed = ((r.nextLong() % MAX_SEED) + MAX_SEED)%MAX_SEED;

        period = 200 + (((r.nextLong()%80)+80)%80)*10;

    }

    /**

     * Next are the methods to compute MBeanInfo.

     * You shouldn't update these methods.

     */

    @Override

    protected String getDescription(MBeanInfo info) {

        return "Wombats are strange beasts. You will find them down under " +

                "and in some computer programms.";

    }

    @Override

    protected String getDescription(MBeanAttributeInfo info) {

        String description = null;

        if (info.getName().equals("Caption")) {

            description = "A simple caption to describe a wombat";

        }

        if (info.getName().equals("Mood")) {

            description = "This Wombat's mood on a [-100,+100] scale."+

                      " -100 means that this wombat is very angry.";

        }

        return description;

    }

    @Override

    protected String getDescription(MBeanOperationInfo op,

            MBeanParameterInfo param,

            int sequence) {

        return null;

    }

    @Override

    protected String getParameterName(MBeanOperationInfo op,

            MBeanParameterInfo param,

            int sequence) {

        return null;

    }

    @Override

    protected String getDescription(MBeanOperationInfo info) {

        String description = null;

        return description;

    }

    @Override

    public MBeanInfo getMBeanInfo() {

        MBeanInfo mbinfo = super.getMBeanInfo();

        return new MBeanInfo(mbinfo.getClassName(),

                mbinfo.getDescription(),

                mbinfo.getAttributes(),

                mbinfo.getConstructors(),

                mbinfo.getOperations(),

                getNotificationInfo());

    }

    /**

     * Get A simple caption to describe a wombat

     */

    public synchronized String getCaption() {

        return caption;

    }

    /**

     * Set A simple caption to describe a wombat

     */

    public void setCaption(String value) {

        final String oldValue;

        synchronized (this) {

            oldValue = caption;

            caption = value;

        }

        final AttributeChangeNotification notif =

                new AttributeChangeNotification(objectName,

                    getNextSeqNumber(),

                    System.currentTimeMillis(),

                    "Caption changed","Caption",

                    String.class.getName(),oldValue,value);

        broadcaster.sendNotification(notif);

    }

    /**

     * MBeanNotification support

     * You shouldn't update these methods

     */

    public void addNotificationListener(NotificationListener listener, NotificationFilter filter, Object handback) throws IllegalArgumentException {

        broadcaster.addNotificationListener(listener, filter, handback);

    }

    public MBeanNotificationInfo[] getNotificationInfo() {

        return new MBeanNotificationInfo[] {

            new MBeanNotificationInfo(new String[] {

                AttributeChangeNotification.ATTRIBUTE_CHANGE},

                javax.management.AttributeChangeNotification.class.getName(),

                "Sent when the caption changes")

            };

    }

    public void removeNotificationListener(NotificationListener listener) throws ListenerNotFoundException {

        broadcaster.removeNotificationListener(listener);

    }

    public void removeNotificationListener(NotificationListener listener, NotificationFilter filter, Object handback) throws ListenerNotFoundException {

        broadcaster.removeNotificationListener(listener, filter, handback);

    }

    private synchronized long getNextSeqNumber() {

        return seqNumber++;

    }

    private long seqNumber;

    private final NotificationBroadcasterSupport broadcaster = new NotificationBroadcasterSupport();

    /**

     * Allows the MBean to perform any operations it needs before being

     * registered in the MBean server. If the name of the MBean is not

     * specified, the MBean can provide a name for its registration. If

     * any exception is raised, the MBean will not be registered in the

     * MBean server.

     * @param server The MBean server in which the MBean will be registered.

     * @param name The object name of the MBean. This name is null if the

     * name parameter to one of the createMBean or registerMBean methods in

     * the MBeanServer interface is null. In that case, this method must

     * return a non-null ObjectName for the new MBean.

     * @return The name under which the MBean is to be registered. This value

     * must not be null. If the name parameter is not null, it will usually

     * but not necessarily be the returned value.

     * @throws Exception This exception will be caught by the MBean server and

     * re-thrown as an MBeanRegistrationException.

     */

    @Override

    public ObjectName preRegister(MBeanServer server, ObjectName name)

            throws Exception {

        objectName = name;

        mbeanServer = server;

        return super.preRegister(server, name);

    }

    /**

     * Allows the MBean to perform any operations needed after having

     * been registered in the MBean server or after the registration has

     * failed.

     * @param registrationDone Indicates wether or not the MBean has been

     * successfully registered in the MBean server. The value false means

     * that the registration has failed.

     */

    @Override

    public void postRegister(Boolean registrationDone) {

        super.postRegister(registrationDone);

    }

    /**

     * Allows the MBean to perform any operations it needs before being

     * unregistered by the MBean server.

     * @throws Exception This exception will be caught by the MBean server and

     * re-thrown as an MBeanRegistrationException.

     */

    @Override

    public void preDeregister() throws Exception {

        super.preDeregister();

    }

    /**

     * Allows the MBean to perform any operations needed after having been

     * unregistered in the MBean server.

     */

    @Override

    public void postDeregister() {

        super.postDeregister();

    }

    public Set<ObjectName> listMatching(ObjectName pattern) {

        return mbeanServer.queryNames(pattern, null);

    }

    private MBeanServer mbeanServer;

    private ObjectName objectName;

}