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

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 * 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

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 * accompanied this code).

 *

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package javax.management;

import java.util.concurrent.CopyOnWriteArrayList;  // for Javadoc

/**

 * <p>Interface implemented by an MBean that emits Notifications. It

 * allows a listener to be registered with the MBean as a notification

 * listener.</p>

 *

 * <h3>Notification dispatch</h3>

 *

 *<p>When an MBean emits a notification, it considers each listener that has been

 * added with {@link #addNotificationListener addNotificationListener} and not

 * subsequently removed with {@link #removeNotificationListener removeNotificationListener}.

 * If a filter was provided with that listener, and if the filter's

 * {@link NotificationFilter#isNotificationEnabled isNotificationEnabled} method returns

 * false, the listener is ignored.  Otherwise, the listener's

 * {@link NotificationListener#handleNotification handleNotification} method is called with

 * the notification, as well as the handback object that was provided to

 * {@code addNotificationListener}.</p>

 *

 * <p>If the same listener is added more than once, it is considered as many times as it was

 * added.  It is often useful to add the same listener with different filters or handback

 * objects.</p>

 *

 * <p>Implementations of this interface can differ regarding the thread in which the methods

 * of filters and listeners are called.</p>

 *

 * <p>If the method call of a filter or listener throws an {@link Exception}, then that

 * exception should not prevent other listeners from being invoked.  However, if the method

 * call throws an {@link Error}, then it is recommended that processing of the notification

 * stop at that point, and if it is possible to propagate the {@code Error} to the sender of

 * the notification, this should be done.</p>

 *

 * <p>This interface should be used by new code in preference to the

 * {@link NotificationBroadcaster} interface.</p>

 *

 * <p>Implementations of this interface and of {@code NotificationBroadcaster}

 * should be careful about synchronization.  In particular, it is not a good

 * idea for an implementation to hold any locks while it is calling a

 * listener.  To deal with the possibility that the list of listeners might

 * change while a notification is being dispatched, a good strategy is to

 * use a {@link CopyOnWriteArrayList} for this list.

 *

 * @since 1.5

 */

public interface NotificationEmitter extends NotificationBroadcaster {

    /**

     * <p>Removes a listener from this MBean.  The MBean must have a

     * listener that exactly matches the given <code>listener</code>,

     * <code>filter</code>, and <code>handback</code> parameters.  If

     * there is more than one such listener, only one is removed.</p>

     *

     * <p>The <code>filter</code> and <code>handback</code> parameters

     * may be null if and only if they are null in a listener to be

     * removed.</p>

     *

     * @param listener A listener that was previously added to this

     * MBean.

     * @param filter The filter that was specified when the listener

     * was added.

     * @param handback The handback that was specified when the listener was

     * added.

     *

     * @exception ListenerNotFoundException The listener is not

     * registered with the MBean, or it is not registered with the

     * given filter and handback.

     */

    public void removeNotificationListener(NotificationListener listener,

                                           NotificationFilter filter,

                                           Object handback)

            throws ListenerNotFoundException;

}