/*

 * CDDL HEADER START

 *

 * The contents of this file are subject to the terms of the

 * Common Development and Distribution License (the "License").

 * You may not use this file except in compliance with the License.

 *

 * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE

 * or http://www.opensolaris.org/os/licensing.

 * See the License for the specific language governing permissions

 * and limitations under the License.

 *

 * When distributing Covered Code, include this CDDL HEADER in each

 * file and include the License file at usr/src/OPENSOLARIS.LICENSE.

 * If applicable, add the following below this CDDL HEADER, with the

 * fields enclosed by brackets "[]" replaced with your own identifying

 * information: Portions Copyright [yyyy] [name of copyright owner]

 *

 * CDDL HEADER END

 */

/*

 * Copyright (c) 2010, Oracle and/or its affiliates. All rights reserved.

 */

package org.opensolaris.os.vp.panel.common;

import java.beans.*;

import javax.management.*;

import org.opensolaris.os.vp.util.misc.event.PropertyChangeListeners;

/**

 * The {@code MXBeanTracker} is a {@link ConnectionTracker} that automatically

 * creates and re-creates an {@link #getBean MXBean} after changes in the {@link

 * #setMBeanServerConnection MBeanServerConnection} or {@link #setObjectName

 * ObjectName}.

 * </p>

 * A property change notification is sent out when the tracked {@code MXBean}

 * changes.

 */

public class MXBeanTracker<T> extends ConnectionTracker {

    //

    // Static data

    //

    /**

     * The name of the property that changes with {@link #setBean}.

     */

    public static final String PROPERTY_BEAN = "bean";

    //

    // Instance data

    //

    private Class<T> clazz;

    private T bean;

    private PropertyChangeListener pListener =

	new PropertyChangeListener() {

	    @Override

	    public void propertyChange(PropertyChangeEvent event) {

		setBean();

	    }

	};

    //

    // Constructors

    //

    public MXBeanTracker(Class<T> clazz) {

	init(clazz);

    }

    public MXBeanTracker(Class<T> clazz, ClientContext context,

	ObjectName oName) {

	super(context, oName);

	init(clazz);

    }

    //

    // MXBeanTracker methods

    //

    public T getBean() {

	return bean;

    }

    protected void setBean(T bean) {

	if (this.bean != bean) {

	    PropertyChangeEvent e = new PropertyChangeEvent(

		this, PROPERTY_BEAN, this.bean, bean);

	    this.bean = bean;

	    getPropertyChangeListeners().propertyChange(e);

	}

    }

    //

    // Private methods

    //

    private void init(Class<T> clazz) {

	this.clazz = clazz;

	addPropertyChangeListener(PROPERTY_MBSC, pListener);

	addPropertyChangeListener(PROPERTY_OBJECTNAME, pListener);

	setBean();

    }

    private void setBean() {

	T bean = null;

	MBeanServerConnection mbsc = getMBeanServerConnection();

	if (mbsc != null) {

	    ObjectName oName = getObjectName();

	    if (oName != null) {

		bean = JMX.newMXBeanProxy(mbsc, oName, clazz);

	    }

	}

	setBean(bean);

    }

}