1 /***
2 * Redistribution and use in source and binary forms, with or without
3 * modification, are permitted provided that the following conditions are
4 * met :
5 *
6 * . Redistributions of source code must retain the above copyright
7 * notice, this list of conditions and the following disclaimer.
8 *
9 * . Redistributions in binary form must reproduce the above copyright
10 * notice, this list of conditions and the following disclaimer in the
11 * documentation and/or other materials provided with the distribution.
12 *
13 * . The name of the author may not be used to endorse or promote products
14 * derived from this software without specific prior written permission.
15 *
16 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
17 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
18 * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
19 * DISCLAIMED. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT,
20 * INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
21 * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
22 * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
23 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
24 * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
25 * ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
26 * POSSIBILITY OF SUCH DAMAGE.
27 *
28 * $Id: LoginObserver.java,v 1.1 2005/09/07 23:34:37 mat007 Exp $
29 */
30
31 package jtge.engine.security;
32
33 import java.util.Iterator;
34 import java.util.Vector;
35 import jtge.engine.handler.IConsumer;
36 import jtge.engine.user.IUser;
37
38 /***
39 * Adapts user login/logout notifications.
40 * <p>
41 * This class sends a login result to a given consumer when a new user logs in.
42 * <p>
43 * It also sends to the output for this new user a login update listing all current logged in users.
44 * <p>
45 * A logout result is sent out when a user logs off.
46 *
47 * @author Mathieu Champlon
48 * @version $Revision: 1.1 $ $Date: 2005/09/07 23:34:37 $
49 */
50 public class LoginObserver implements ILoginObserver
51 {
52 private final IConsumer consumer;
53 private final Vector users;
54 private final Vector views;
55
56 /***
57 * Create a login context.
58 *
59 * @param consumer the update/result output
60 */
61 public LoginObserver( final IConsumer consumer )
62 {
63 if( consumer == null )
64 throw new IllegalArgumentException( "argument 'consumer' is null" );
65 this.consumer = consumer;
66 this.users = new Vector();
67 this.views = new Vector();
68 }
69
70 /***
71 * Register a view to receive login events.
72 *
73 * @param view the view to register
74 */
75 public final void register( final ILoginView view )
76 {
77 if( view != null )
78 views.add( view );
79 }
80
81 /***
82 * {@inheritDoc}
83 */
84 public final void login( final IUser user, final IConsumer consumer )
85 {
86 consumer.handle( new LoginUpdate( users ) );
87 users.add( user );
88 this.consumer.handle( new LoginResult( user ) );
89 final Iterator iterator = views.iterator();
90 while( iterator.hasNext() )
91 ((ILoginView)iterator.next()).login( user );
92 }
93
94 /***
95 * {@inheritDoc}
96 */
97 public final void logout( final IUser user )
98 {
99 users.remove( user );
100 consumer.handle( new LogoutResult( user ) );
101 final Iterator iterator = views.iterator();
102 while( iterator.hasNext() )
103 ((ILoginView)iterator.next()).logout( user );
104 }
105 }