001    /*
002     * Copyright (c) OSGi Alliance (2002, 2008). All Rights Reserved.
003     *
004     * Licensed under the Apache License, Version 2.0 (the "License");
005     * you may not use this file except in compliance with the License.
006     * You may obtain a copy of the License at
007     *
008     *      http://www.apache.org/licenses/LICENSE-2.0
009     *
010     * Unless required by applicable law or agreed to in writing, software
011     * distributed under the License is distributed on an "AS IS" BASIS,
012     * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
013     * See the License for the specific language governing permissions and
014     * limitations under the License.
015     */
016    package org.osgi.service.wireadmin;
017    
018    /**
019     * Listener for Wire Admin Events.
020     * 
021     * <p>
022     * <code>WireAdminListener</code> objects are registered with the Framework
023     * service registry and are notified with a <code>WireAdminEvent</code> object
024     * when an event is broadcast.
025     * <p>
026     * <code>WireAdminListener</code> objects can inspect the received
027     * <code>WireAdminEvent</code> object to determine its type, the <code>Wire</code>
028     * object with which it is associated, and the Wire Admin service that
029     * broadcasts the event.
030     * 
031     * <p>
032     * <code>WireAdminListener</code> objects must be registered with a service
033     * property {@link WireConstants#WIREADMIN_EVENTS} whose value is a bitwise OR
034     * of all the event types the listener is interested in receiving.
035     * <p>
036     * For example:
037     * 
038     * <pre>
039     * Integer mask = new Integer(WIRE_TRACE | WIRE_CONNECTED | WIRE_DISCONNECTED);
040     * Hashtable ht = new Hashtable();
041     * ht.put(WIREADMIN_EVENTS, mask);
042     * context.registerService(WireAdminListener.class.getName(), this, ht);
043     * </pre>
044     * 
045     * If a <code>WireAdminListener</code> object is registered without a service
046     * property {@link WireConstants#WIREADMIN_EVENTS}, then the
047     * <code>WireAdminListener</code> will receive no events.
048     * 
049     * <p>
050     * Security Considerations. Bundles wishing to monitor <code>WireAdminEvent</code>
051     * objects will require <code>ServicePermission[WireAdminListener,REGISTER]</code>
052     * to register a <code>WireAdminListener</code> service. Since
053     * <code>WireAdminEvent</code> objects contain <code>Wire</code> objects, care must
054     * be taken in assigning permission to register a <code>WireAdminListener</code>
055     * service.
056     * 
057     * @see WireAdminEvent
058     * 
059     * @version $Revision: 5673 $
060     */
061    public interface WireAdminListener {
062            /**
063             * Receives notification of a broadcast <code>WireAdminEvent</code> object.
064             * 
065             * The event object will be of an event type specified in this
066             * <code>WireAdminListener</code> service's
067             * {@link WireConstants#WIREADMIN_EVENTS} service property.
068             * 
069             * @param event The <code>WireAdminEvent</code> object.
070             */
071            void wireAdminEvent(WireAdminEvent event);
072    }