/*
 * Copyright (c) OSGi Alliance (2000, 2015). All Rights Reserved.
 * 
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *      http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

package org.osgi.framework;

import java.util.EventListener;
import org.osgi.annotation.versioning.ConsumerType;

A ServiceEvent listener. ServiceListener is a listener interface that may be implemented by a bundle developer. When a ServiceEvent is fired, it is synchronously delivered to a ServiceListener. The Framework may deliver ServiceEvent objects to a ServiceListener out of order and may concurrently call and/or reenter a ServiceListener. 
 A ServiceListener object is registered with the Framework using the BundleContext.addServiceListener method. ServiceListener objects are called with a ServiceEvent object when a service is registered, modified, or is in the process of unregistering. 
 ServiceEvent object delivery to ServiceListener objects is filtered by the filter specified when the listener was registered. If the Java Runtime Environment supports permissions, then additional filtering is done. ServiceEvent objects are only delivered to the listener if the bundle which defines the listener object's class has the appropriate ServicePermission to get the service using at least one of the named classes under which the service was registered. 
 ServiceEvent object delivery to ServiceListener objects is further filtered according to package sources as defined in ServiceReference.isAssignableTo(Bundle, String). 
Author:
$Id: e061a4c69c017c04dafe285926424bd1a2132b51 $
See Also:
ServiceEvent
ServicePermission
@ThreadSafe
/**
 * A {@code ServiceEvent} listener. {@code ServiceListener} is a listener
 * interface that may be implemented by a bundle developer. When a
 * {@code ServiceEvent} is fired, it is synchronously delivered to a
 * {@code ServiceListener}. The Framework may deliver {@code ServiceEvent}
 * objects to a {@code ServiceListener} out of order and may concurrently call
 * and/or reenter a {@code ServiceListener}.
 * 
 * <p>
 * A {@code ServiceListener} object is registered with the Framework using the
 * {@code BundleContext.addServiceListener} method. {@code ServiceListener}
 * objects are called with a {@code ServiceEvent} object when a service is
 * registered, modified, or is in the process of unregistering.
 * 
 * <p>
 * {@code ServiceEvent} object delivery to {@code ServiceListener} objects is
 * filtered by the filter specified when the listener was registered. If the
 * Java Runtime Environment supports permissions, then additional filtering is
 * done. {@code ServiceEvent} objects are only delivered to the listener if the
 * bundle which defines the listener object's class has the appropriate
 * {@code ServicePermission} to get the service using at least one of the named
 * classes under which the service was registered.
 * 
 * <p>
 * {@code ServiceEvent} object delivery to {@code ServiceListener} objects is
 * further filtered according to package sources as defined in
 * {@link ServiceReference#isAssignableTo(Bundle, String)}.
 * 
 * @see ServiceEvent
 * @see ServicePermission
 * @ThreadSafe
 * @author $Id: e061a4c69c017c04dafe285926424bd1a2132b51 $
 */
@ConsumerType
@FunctionalInterface
public interface ServiceListener extends EventListener {
	
Receives notification that a service has had a lifecycle change.
Params:
event – The ServiceEvent object./**
	 * Receives notification that a service has had a lifecycle change.
	 * 
	 * @param event The {@code ServiceEvent} object.
	 */
	public void serviceChanged(ServiceEvent event);
}