1 /*
2 * Copyright (c) 1997, 2013, Oracle and/or its affiliates. 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. Oracle designates this
8 * particular file as subject to the "Classpath" exception as provided
9 * by Oracle 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 Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
22 * or visit www.oracle.com if you need additional information or have any
23 * questions.
24 */
25
26 package java.rmi.activation;
27
28 import java.rmi.server.UID;
29
30 /**
31 * The identifier for a registered activation group serves several
32 * purposes: <ul>
33 * <li>identifies the group uniquely within the activation system, and
34 * <li>contains a reference to the group's activation system so that the
35 * group can contact its activation system when necessary.</ul><p>
36 *
37 * The <code>ActivationGroupID</code> is returned from the call to
38 * <code>ActivationSystem.registerGroup</code> and is used to identify
39 * the group within the activation system. This group id is passed
40 * as one of the arguments to the activation group's special constructor
41 * when an activation group is created/recreated.
42 *
43 * @author Ann Wollrath
44 * @see ActivationGroup
45 * @see ActivationGroupDesc
46 * @since 1.2
47 */
48 public class ActivationGroupID implements java.io.Serializable {
49 /**
50 * @serial The group's activation system.
51 */
52 private ActivationSystem system;
53
54 /**
55 * @serial The group's unique id.
56 */
57 private UID uid = new UID();
58
59 /** indicate compatibility with the Java 2 SDK v1.2 version of class */
60 private static final long serialVersionUID = -1648432278909740833L;
61
62 /**
63 * Constructs a unique group id.
64 *
65 * @param system the group's activation system
66 * @throws UnsupportedOperationException if and only if activation is
67 * not supported by this implementation
68 * @since 1.2
69 */
70 public ActivationGroupID(ActivationSystem system) {
71 this.system = system;
72 }
73
74 /**
75 * Returns the group's activation system.
76 * @return the group's activation system
77 * @since 1.2
78 */
79 public ActivationSystem getSystem() {
80 return system;
81 }
82
83 /**
84 * Returns a hashcode for the group's identifier. Two group
85 * identifiers that refer to the same remote group will have the
86 * same hash code.
87 *
88 * @see java.util.Hashtable
89 * @since 1.2
90 */
91 public int hashCode() {
92 return uid.hashCode();
93 }
94
95 /**
96 * Compares two group identifiers for content equality.
97 * Returns true if both of the following conditions are true:
98 * 1) the unique identifiers are equivalent (by content), and
99 * 2) the activation system specified in each
100 * refers to the same remote object.
101 *
102 * @param obj the Object to compare with
103 * @return true if these Objects are equal; false otherwise.
104 * @see java.util.Hashtable
105 * @since 1.2
106 */
107 public boolean equals(Object obj) {
108 if (this == obj) {
109 return true;
110 } else if (obj instanceof ActivationGroupID) {
111 ActivationGroupID id = (ActivationGroupID)obj;
112 return (uid.equals(id.uid) && system.equals(id.system));
113 } else {
114 return false;
115 }
116 }
117 }