KickJava   Java API By Example, From Geeks To Geeks.

Java > Open Source Codes > org > osgi > framework > ServiceListener


1 /*
2  * $Header: /cvshome/build/org.osgi.framework/src/org/osgi/framework/ServiceListener.java,v 1.15 2007/02/20 00:16:30 hargrave Exp $
3  *
4  * Copyright (c) OSGi Alliance (2000, 2007). All Rights Reserved.
5  *
6  * Licensed under the Apache License, Version 2.0 (the "License");
7  * you may not use this file except in compliance with the License.
8  * You may obtain a copy of the License at
9  *
10  * http://www.apache.org/licenses/LICENSE-2.0
11  *
12  * Unless required by applicable law or agreed to in writing, software
13  * distributed under the License is distributed on an "AS IS" BASIS,
14  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
15  * See the License for the specific language governing permissions and
16  * limitations under the License.
17  */
18
19 package org.osgi.framework;
20
21 import java.util.EventListener JavaDoc;
22
23 /**
24  * A <code>ServiceEvent</code> listener. <code>ServiceListener</code> is a
25  * listener interface that may be implemented by a bundle developer. When a
26  * <code>ServiceEvent</code> is fired, it is synchronously delivered to a
27  * <code>ServiceListener</code>. The Framework may deliver
28  * <code>ServiceEvent</code> objects to a <code>ServiceListener</code> out
29  * of order and may concurrently call and/or reenter a
30  * <code>ServiceListener</code>.
31  *
32  * <p>
33  * A <code>ServiceListener</code> object is registered with the Framework
34  * using the <code>BundleContext.addServiceListener</code> method.
35  * <code>ServiceListener</code> objects are called with a
36  * <code>ServiceEvent</code> object when a service is registered, modified, or
37  * is in the process of unregistering.
38  *
39  * <p>
40  * <code>ServiceEvent</code> object delivery to <code>ServiceListener</code>
41  * objects is filtered by the filter specified when the listener was registered.
42  * If the Java Runtime Environment supports permissions, then additional
43  * filtering is done. <code>ServiceEvent</code> objects are only delivered to
44  * the listener if the bundle which defines the listener object's class has the
45  * appropriate <code>ServicePermission</code> to get the service using at
46  * least one of the named classes under which the service was registered.
47  *
48  * <p>
49  * <code>ServiceEvent</code> object delivery to <code>ServiceListener</code>
50  * objects is further filtered according to package sources as defined in
51  * {@link ServiceReference#isAssignableTo(Bundle, String)}.
52  *
53  * @see ServiceEvent
54  * @see ServicePermission
55  * @ThreadSafe
56  * @version $Revision: 1.15 $
57  */
58
59 public interface ServiceListener extends EventListener JavaDoc {
60     /**
61      * Receives notification that a service has had a lifecycle change.
62      *
63      * @param event The <code>ServiceEvent</code> object.
64      */
65     public void serviceChanged(ServiceEvent event);
66 }
67
Popular Tags