1 /*
2 * XNap - A P2P framework and client.
3 *
4 * See the file AUTHORS for copyright information.
5 *
6 * This program is free software; you can redistribute it and/or modify
7 * it under the terms of the GNU General Public License as published by
8 * the Free Software Foundation.
9 *
10 * This program is distributed in the hope that it will be useful,
11 * but WITHOUT ANY WARRANTY; without even the implied warranty of
12 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
13 * GNU General Public License for more details.
14 *
15 * You should have received a copy of the GNU General Public License
16 * along with this program; if not, write to the Free Software
17 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
18 */
19
20 package org.xnap.event;
21
22 import java.util.List;
23 import java.util.Vector;
24
25 /***
26 * This is a utility class that can be used by data containers to notify
27 * <code>StateEvent</code> listeners.
28 */
29 public class StateSupport {
30
31 //--- Data field(s) ---
32
33 private Object source;
34 private List listeners = new Vector();
35
36 //--- Constructor(s) ---
37
38 /***
39 * Constructs a StateSupport object.
40 *
41 * @param source the object to be given as the source for any events
42 */
43 public StateSupport(Object source)
44 {
45 this.source = source;
46 }
47
48 //--- Method(s) ---
49
50 public void addStateListener(StateListener listener)
51 {
52 listeners.add(listener);
53 }
54
55 public void removeStateListener(StateListener listener)
56 {
57 listeners.remove(listener);
58 }
59
60 public void fireStateChanged()
61 {
62 Object[] l = listeners.toArray();
63
64 if (l != null) {
65 StateEvent event = new StateEvent(source);
66
67 for (int i = l.length - 1; i >= 0; i--) {
68 ((StateListener)l[i]).stateChanged(event);
69 }
70 }
71 }
72
73 }