1 /*
2 * Copyright 1997-2005 Sun Microsystems, Inc. All Rights Reserved.
3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
4 *
5 * This code is free software; you can redistribute it and/or modify it
6 * under the terms of the GNU General Public License version 2 only, as
7 * published by the Free Software Foundation. Sun designates this
8 * particular file as subject to the "Classpath" exception as provided
9 * by Sun in the LICENSE file that accompanied this code.
10 *
11 * This code is distributed in the hope that it will be useful, but WITHOUT
12 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
13 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
14 * version 2 for more details (a copy is included in the LICENSE file that
15 * accompanied this code).
16 *
17 * You should have received a copy of the GNU General Public License version
18 * 2 along with this work; if not, write to the Free Software Foundation,
19 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
20 *
21 * Please contact Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,
22 * CA 95054 USA or visit www.sun.com if you need additional information or
23 * have any questions.
24 */
25
26 package java.rmi.activation;
27
28 import java.rmi.MarshalledObject;
29 import java.rmi.Remote;
30 import java.rmi.RemoteException;
31 import java.rmi.activation.UnknownGroupException;
32 import java.rmi.activation.UnknownObjectException;
33
34 /**
35 * An <code>ActivationMonitor</code> is specific to an
36 * <code>ActivationGroup</code> and is obtained when a group is
37 * reported active via a call to
38 * <code>ActivationSystem.activeGroup</code> (this is done
39 * internally). An activation group is responsible for informing its
40 * <code>ActivationMonitor</code> when either: its objects become active or
41 * inactive, or the group as a whole becomes inactive.
42 *
43 * @author Ann Wollrath
44 * @see Activator
45 * @see ActivationSystem
46 * @see ActivationGroup
47 * @since 1.2
48 */
49 public interface ActivationMonitor extends Remote {
50
51 /**
52 * An activation group calls its monitor's
53 * <code>inactiveObject</code> method when an object in its group
54 * becomes inactive (deactivates). An activation group discovers
55 * that an object (that it participated in activating) in its VM
56 * is no longer active, via calls to the activation group's
57 * <code>inactiveObject</code> method. <p>
58 *
59 * The <code>inactiveObject</code> call informs the
60 * <code>ActivationMonitor</code> that the remote object reference
61 * it holds for the object with the activation identifier,
62 * <code>id</code>, is no longer valid. The monitor considers the
63 * reference associated with <code>id</code> as a stale reference.
64 * Since the reference is considered stale, a subsequent
65 * <code>activate</code> call for the same activation identifier
66 * results in re-activating the remote object.<p>
67 *
68 * @param id the object's activation identifier
69 * @exception UnknownObjectException if object is unknown
70 * @exception RemoteException if remote call fails
71 * @since 1.2
72 */
73 public void inactiveObject(ActivationID id)
74 throws UnknownObjectException, RemoteException;
75
76 /**
77 * Informs that an object is now active. An <code>ActivationGroup</code>
78 * informs its monitor if an object in its group becomes active by
79 * other means than being activated directly (i.e., the object
80 * is registered and "activated" itself).
81 *
82 * @param id the active object's id
83 * @param obj the marshalled form of the object's stub
84 * @exception UnknownObjectException if object is unknown
85 * @exception RemoteException if remote call fails
86 * @since 1.2
87 */
88 public void activeObject(ActivationID id,
89 MarshalledObject<? extends Remote> obj)
90 throws UnknownObjectException, RemoteException;
91
92 /**
93 * Informs that the group is now inactive. The group will be
94 * recreated upon a subsequent request to activate an object
95 * within the group. A group becomes inactive when all objects
96 * in the group report that they are inactive.
97 *
98 * @param id the group's id
99 * @param incarnation the group's incarnation number
100 * @exception UnknownGroupException if group is unknown
101 * @exception RemoteException if remote call fails
102 * @since 1.2
103 */
104 public void inactiveGroup(ActivationGroupID id,
105 long incarnation)
106 throws UnknownGroupException, RemoteException;
107
108 }
Save This Page