/*
 * Copyright (c) OSGi Alliance (2002, 2017). 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.service.wireadmin;

/**
 * Listener for Wire Admin Events.
 * 
 * <p>
 * {@code WireAdminListener} objects are registered with the Framework service
 * registry and are notified with a {@code WireAdminEvent} object when an event
 * is broadcast.
 * <p>
 * {@code WireAdminListener} objects can inspect the received
 * {@code WireAdminEvent} object to determine its type, the {@code Wire} object
 * with which it is associated, and the Wire Admin service that broadcasts the
 * event.
 * 
 * <p>
 * {@code WireAdminListener} objects must be registered with a service property
 * {@link WireConstants#WIREADMIN_EVENTS} whose value is a bitwise OR of all the
 * event types the listener is interested in receiving.
 * <p>
 * For example:
 * 
 * <pre>
 * Integer mask = Integer.valueOf(WIRE_TRACE | WIRE_CONNECTED | WIRE_DISCONNECTED);
 * Hashtable ht = new Hashtable();
 * ht.put(WIREADMIN_EVENTS, mask);
 * context.registerService(WireAdminListener.class.getName(), this, ht);
 * </pre>
 * 
 * If a {@code WireAdminListener} object is registered without a service
 * property {@link WireConstants#WIREADMIN_EVENTS}, then the
 * {@code WireAdminListener} will receive no events.
 * 
 * <p>
 * Security Considerations. Bundles wishing to monitor {@code WireAdminEvent}
 * objects will require {@code ServicePermission[WireAdminListener,REGISTER]} to
 * register a {@code WireAdminListener} service. Since {@code WireAdminEvent}
 * objects contain {@code Wire} objects, care must be taken in assigning
 * permission to register a {@code WireAdminListener} service.
 * 
 * @see WireAdminEvent
 * 
 * @author $Id: 73968c8d158a046f9b86f02edeb187ad0435055d $
 */
public interface WireAdminListener {
	/**
	 * Receives notification of a broadcast {@code WireAdminEvent} object.
	 * 
	 * The event object will be of an event type specified in this
	 * {@code WireAdminListener} service's
	 * {@link WireConstants#WIREADMIN_EVENTS} service property.
	 * 
	 * @param event The {@code WireAdminEvent} object.
	 */
	void wireAdminEvent(WireAdminEvent event);
}
