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	/*
	* Copyright (c) 2005, 2013, Oracle and/or its affiliates. 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. Oracle designates this
	* particular file as subject to the "Classpath" exception as provided
	* by Oracle in the LICENSE file that accompanied this code.
	*
	* 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 Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
	* or visit www.oracle.com if you need additional information or have any
	* questions.
	*/

	package javax.management;

	/**
	* <p>An MBean whose management interface is determined by reflection
	* on a Java interface, and that emits notifications.</p>
	*
	* <p>The following example shows how to use the public constructor
	* {@link #StandardEmitterMBean(Object, Class, NotificationEmitter)
	* StandardEmitterMBean(implementation, mbeanInterface, emitter)} to
	* create an MBean emitting notifications with any
	* implementation class name <i>Impl</i>, with a management
	* interface defined (as for current Standard MBeans) by any interface
	* <i>Intf</i>, and with any implementation of the interface
	* {@link NotificationEmitter}. The example uses the class
	* {@link NotificationBroadcasterSupport} as an implementation
	* of the interface {@link NotificationEmitter}.</p>
	*
	* <pre>
	* MBeanServer mbs;
	* ...
	* final String[] types = new String[] {"sun.disc.space","sun.disc.alarm"};
	* final MBeanNotificationInfo info = new MBeanNotificationInfo(
	* types,
	* Notification.class.getName(),
	* "Notification about disc info.");
	* final NotificationEmitter emitter =
	* new NotificationBroadcasterSupport(info);
	*
	* final Intf impl = new Impl(...);
	* final Object mbean = new StandardEmitterMBean(
	* impl, Intf.class, emitter);
	* mbs.registerMBean(mbean, objectName);
	* </pre>
	*
	* @see StandardMBean
	*
	* @since 1.6
	*/
	public class StandardEmitterMBean extends StandardMBean
	implements NotificationEmitter {

	private static final MBeanNotificationInfo[] NO_NOTIFICATION_INFO =
	new MBeanNotificationInfo[0];

	private final NotificationEmitter emitter;
	private final MBeanNotificationInfo[] notificationInfo;

	/**
	* <p>Make an MBean whose management interface is specified by
	* {@code mbeanInterface}, with the given implementation and
	* where notifications are handled by the given {@code NotificationEmitter}.
	* The resultant MBean implements the {@code NotificationEmitter} interface
	* by forwarding its methods to {@code emitter}. It is legal and useful
	* for {@code implementation} and {@code emitter} to be the same object.</p>
	*
	* <p>If {@code emitter} is an instance of {@code
	* NotificationBroadcasterSupport} then the MBean's {@link #sendNotification
	* sendNotification} method will call {@code emitter.}{@link
	* NotificationBroadcasterSupport#sendNotification sendNotification}.</p>
	*
	* <p>The array returned by {@link #getNotificationInfo()} on the
	* new MBean is a copy of the array returned by
	* {@code emitter.}{@link NotificationBroadcaster#getNotificationInfo
	* getNotificationInfo()} at the time of construction. If the array
	* returned by {@code emitter.getNotificationInfo()} later changes,
	* that will have no effect on this object's
	* {@code getNotificationInfo()}.</p>
	*
	* @param implementation the implementation of the MBean interface.
	* @param mbeanInterface a Standard MBean interface.
	* @param emitter the object that will handle notifications.
	*
	* @throws IllegalArgumentException if the {@code mbeanInterface}
	* does not follow JMX design patterns for Management Interfaces, or
	* if the given {@code implementation} does not implement the
	* specified interface, or if {@code emitter} is null.
	*/
	public <T> StandardEmitterMBean(T implementation, Class<T> mbeanInterface,
	NotificationEmitter emitter) {
	this(implementation, mbeanInterface, false, emitter);
	}

	/**
	* <p>Make an MBean whose management interface is specified by
	* {@code mbeanInterface}, with the given implementation and where
	* notifications are handled by the given {@code
	* NotificationEmitter}. This constructor can be used to make
	* either Standard MBeans or MXBeans. The resultant MBean
	* implements the {@code NotificationEmitter} interface by
	* forwarding its methods to {@code emitter}. It is legal and
	* useful for {@code implementation} and {@code emitter} to be the
	* same object.</p>
	*
	* <p>If {@code emitter} is an instance of {@code
	* NotificationBroadcasterSupport} then the MBean's {@link #sendNotification
	* sendNotification} method will call {@code emitter.}{@link
	* NotificationBroadcasterSupport#sendNotification sendNotification}.</p>
	*
	* <p>The array returned by {@link #getNotificationInfo()} on the
	* new MBean is a copy of the array returned by
	* {@code emitter.}{@link NotificationBroadcaster#getNotificationInfo
	* getNotificationInfo()} at the time of construction. If the array
	* returned by {@code emitter.getNotificationInfo()} later changes,
	* that will have no effect on this object's
	* {@code getNotificationInfo()}.</p>
	*
	* @param implementation the implementation of the MBean interface.
	* @param mbeanInterface a Standard MBean interface.
	* @param isMXBean If true, the {@code mbeanInterface} parameter
	* names an MXBean interface and the resultant MBean is an MXBean.
	* @param emitter the object that will handle notifications.
	*
	* @throws IllegalArgumentException if the {@code mbeanInterface}
	* does not follow JMX design patterns for Management Interfaces, or
	* if the given {@code implementation} does not implement the
	* specified interface, or if {@code emitter} is null.
	*/
	public <T> StandardEmitterMBean(T implementation, Class<T> mbeanInterface,
	boolean isMXBean,
	NotificationEmitter emitter) {
	super(implementation, mbeanInterface, isMXBean);
	if (emitter == null)
	throw new IllegalArgumentException("Null emitter");
	this.emitter = emitter;
	MBeanNotificationInfo[] infos = emitter.getNotificationInfo();
	if (infos == null \|\| infos.length == 0) {
	this.notificationInfo = NO_NOTIFICATION_INFO;
	} else {
	this.notificationInfo = infos.clone();
	}
	}

	/**
	* <p>Make an MBean whose management interface is specified by
	* {@code mbeanInterface}, and
	* where notifications are handled by the given {@code NotificationEmitter}.
	* The resultant MBean implements the {@code NotificationEmitter} interface
	* by forwarding its methods to {@code emitter}.</p>
	*
	* <p>If {@code emitter} is an instance of {@code
	* NotificationBroadcasterSupport} then the MBean's {@link #sendNotification
	* sendNotification} method will call {@code emitter.}{@link
	* NotificationBroadcasterSupport#sendNotification sendNotification}.</p>
	*
	* <p>The array returned by {@link #getNotificationInfo()} on the
	* new MBean is a copy of the array returned by
	* {@code emitter.}{@link NotificationBroadcaster#getNotificationInfo
	* getNotificationInfo()} at the time of construction. If the array
	* returned by {@code emitter.getNotificationInfo()} later changes,
	* that will have no effect on this object's
	* {@code getNotificationInfo()}.</p>
	*
	* <p>This constructor must be called from a subclass that implements
	* the given {@code mbeanInterface}.</p>
	*
	* @param mbeanInterface a StandardMBean interface.
	* @param emitter the object that will handle notifications.
	*
	* @throws IllegalArgumentException if the {@code mbeanInterface}
	* does not follow JMX design patterns for Management Interfaces, or
	* if {@code this} does not implement the specified interface, or
	* if {@code emitter} is null.
	*/
	protected StandardEmitterMBean(Class<?> mbeanInterface,
	NotificationEmitter emitter) {
	this(mbeanInterface, false, emitter);
	}

	/**
	* <p>Make an MBean whose management interface is specified by
	* {@code mbeanInterface}, and where notifications are handled by
	* the given {@code NotificationEmitter}. This constructor can be
	* used to make either Standard MBeans or MXBeans. The resultant
	* MBean implements the {@code NotificationEmitter} interface by
	* forwarding its methods to {@code emitter}.</p>
	*
	* <p>If {@code emitter} is an instance of {@code
	* NotificationBroadcasterSupport} then the MBean's {@link #sendNotification
	* sendNotification} method will call {@code emitter.}{@link
	* NotificationBroadcasterSupport#sendNotification sendNotification}.</p>
	*
	* <p>The array returned by {@link #getNotificationInfo()} on the
	* new MBean is a copy of the array returned by
	* {@code emitter.}{@link NotificationBroadcaster#getNotificationInfo
	* getNotificationInfo()} at the time of construction. If the array
	* returned by {@code emitter.getNotificationInfo()} later changes,
	* that will have no effect on this object's
	* {@code getNotificationInfo()}.</p>
	*
	* <p>This constructor must be called from a subclass that implements
	* the given {@code mbeanInterface}.</p>
	*
	* @param mbeanInterface a StandardMBean interface.
	* @param isMXBean If true, the {@code mbeanInterface} parameter
	* names an MXBean interface and the resultant MBean is an MXBean.
	* @param emitter the object that will handle notifications.
	*
	* @throws IllegalArgumentException if the {@code mbeanInterface}
	* does not follow JMX design patterns for Management Interfaces, or
	* if {@code this} does not implement the specified interface, or
	* if {@code emitter} is null.
	*/
	protected StandardEmitterMBean(Class<?> mbeanInterface, boolean isMXBean,
	NotificationEmitter emitter) {
	super(mbeanInterface, isMXBean);
	if (emitter == null)
	throw new IllegalArgumentException("Null emitter");
	this.emitter = emitter;
	MBeanNotificationInfo[] infos = emitter.getNotificationInfo();
	if (infos == null \|\| infos.length == 0) {
	this.notificationInfo = NO_NOTIFICATION_INFO;
	} else {
	this.notificationInfo = infos.clone();
	}
	}

	public void removeNotificationListener(NotificationListener listener)
	throws ListenerNotFoundException {
	emitter.removeNotificationListener(listener);
	}

	public void removeNotificationListener(NotificationListener listener,
	NotificationFilter filter,
	Object handback)
	throws ListenerNotFoundException {
	emitter.removeNotificationListener(listener, filter, handback);
	}

	public void addNotificationListener(NotificationListener listener,
	NotificationFilter filter,
	Object handback) {
	emitter.addNotificationListener(listener, filter, handback);
	}

	public MBeanNotificationInfo[] getNotificationInfo() {
	// this getter might get called from the super constructor
	// when the notificationInfo has not been properly set yet
	if (notificationInfo == null) {
	return NO_NOTIFICATION_INFO;
	}
	if (notificationInfo.length == 0) {
	return notificationInfo;
	} else {
	return notificationInfo.clone();
	}
	}

	/**
	* <p>Sends a notification.</p>
	*
	* <p>If the {@code emitter} parameter to the constructor was an
	* instance of {@code NotificationBroadcasterSupport} then this
	* method will call {@code emitter.}{@link
	* NotificationBroadcasterSupport#sendNotification
	* sendNotification}.</p>
	*
	* @param n the notification to send.
	*
	* @throws ClassCastException if the {@code emitter} parameter to the
	* constructor was not a {@code NotificationBroadcasterSupport}.
	*/
	public void sendNotification(Notification n) {
	if (emitter instanceof NotificationBroadcasterSupport)
	((NotificationBroadcasterSupport) emitter).sendNotification(n);
	else {
	final String msg =
	"Cannot sendNotification when emitter is not an " +
	"instance of NotificationBroadcasterSupport: " +
	emitter.getClass().getName();
	throw new ClassCastException(msg);
	}
	}

	/**
	* <p>Get the MBeanNotificationInfo[] that will be used in the
	* MBeanInfo returned by this MBean.</p>
	*
	* <p>The default implementation of this method returns
	* {@link #getNotificationInfo()}.</p>
	*
	* @param info The default MBeanInfo derived by reflection.
	* @return the MBeanNotificationInfo[] for the new MBeanInfo.
	*/
	@Override
	MBeanNotificationInfo[] getNotifications(MBeanInfo info) {
	return getNotificationInfo();
	}
	}

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