KickJava   Java API By Example, From Geeks To Geeks.

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


1 /*
2  * $Header: /cvshome/build/org.osgi.framework/src/org/osgi/framework/ServiceEvent.java,v 1.15 2007/02/20 00:14:12 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.EventObject JavaDoc;
22
23 /**
24  * An event from the Framework describing a service lifecycle change.
25  * <p>
26  * <code>ServiceEvent</code> objects are delivered to
27  * <code>ServiceListener</code>s and <code>AllServiceListener</code>s when
28  * a change occurs in this service's lifecycle. A type code is used to identify
29  * the event type for future extendability.
30  *
31  * <p>
32  * OSGi Alliance reserves the right to extend the set of types.
33  *
34  * @Immutable
35  * @see ServiceListener
36  * @see AllServiceListener
37  * @version $Revision: 1.15 $
38  */
39
40 public class ServiceEvent extends EventObject JavaDoc {
41     static final long serialVersionUID = 8792901483909409299L;
42     /**
43      * Reference to the service that had a change occur in its lifecycle.
44      */
45     private final ServiceReference reference;
46
47     /**
48      * Type of service lifecycle change.
49      */
50     private final int type;
51
52     /**
53      * This service has been registered.
54      * <p>
55      * This event is synchronously delivered <strong>after</strong> the service
56      * has been registered with the Framework.
57      *
58      * <p>
59      * The value of <code>REGISTERED</code> is 0x00000001.
60      *
61      * @see BundleContext#registerService(String[],Object,java.util.Dictionary)
62      */
63     public final static int REGISTERED = 0x00000001;
64
65     /**
66      * The properties of a registered service have been modified.
67      * <p>
68      * This event is synchronously delivered <strong>after</strong> the service
69      * properties have been modified.
70      *
71      * <p>
72      * The value of <code>MODIFIED</code> is 0x00000002.
73      *
74      * @see ServiceRegistration#setProperties
75      */
76     public final static int MODIFIED = 0x00000002;
77
78     /**
79      * This service is in the process of being unregistered.
80      * <p>
81      * This event is synchronously delivered <strong>before</strong> the
82      * service has completed unregistering.
83      *
84      * <p>
85      * If a bundle is using a service that is <code>UNREGISTERING</code>, the
86      * bundle should release its use of the service when it receives this event.
87      * If the bundle does not release its use of the service when it receives
88      * this event, the Framework will automatically release the bundle's use of
89      * the service while completing the service unregistration operation.
90      *
91      * <p>
92      * The value of UNREGISTERING is 0x00000004.
93      *
94      * @see ServiceRegistration#unregister
95      * @see BundleContext#ungetService
96      */
97     public final static int UNREGISTERING = 0x00000004;
98
99     /**
100      * Creates a new service event object.
101      *
102      * @param type The event type.
103      * @param reference A <code>ServiceReference</code> object to the service
104      * that had a lifecycle change.
105      */
106     public ServiceEvent(int type, ServiceReference reference) {
107         super(reference);
108         this.reference = reference;
109         this.type = type;
110     }
111
112     /**
113      * Returns a reference to the service that had a change occur in its
114      * lifecycle.
115      * <p>
116      * This reference is the source of the event.
117      *
118      * @return Reference to the service that had a lifecycle change.
119      */
120     public ServiceReference getServiceReference() {
121         return reference;
122     }
123
124     /**
125      * Returns the type of event. The event type values are:
126      * <ul>
127      * <li>{@link #REGISTERED}
128      * <li>{@link #MODIFIED}
129      * <li>{@link #UNREGISTERING}
130      * </ul>
131      *
132      * @return Type of service lifecycle change.
133      */
134
135     public int getType() {
136         return type;
137     }
138 }
139
Popular Tags