1 /***
2 * Redistribution and use of this software and associated documentation
3 * ("Software"), with or without modification, are permitted provided
4 * that the following conditions are met:
5 *
6 * 1. Redistributions of source code must retain copyright
7 * statements and notices. Redistributions must also contain a
8 * copy of this document.
9 *
10 * 2. Redistributions in binary form must reproduce the
11 * above copyright notice, this list of conditions and the
12 * following disclaimer in the documentation and/or other
13 * materials provided with the distribution.
14 *
15 * 3. The name "Exolab" must not be used to endorse or promote
16 * products derived from this Software without prior written
17 * permission of Exoffice Technologies. For written permission,
18 * please contact info@exolab.org.
19 *
20 * 4. Products derived from this Software may not be called "Exolab"
21 * nor may "Exolab" appear in their names without prior written
22 * permission of Exoffice Technologies. Exolab is a registered
23 * trademark of Exoffice Technologies.
24 *
25 * 5. Due credit should be given to the Exolab Project
26 * (http://www.exolab.org/).
27 *
28 * THIS SOFTWARE IS PROVIDED BY EXOFFICE TECHNOLOGIES AND CONTRIBUTORS
29 * ``AS IS'' AND ANY EXPRESSED OR IMPLIED WARRANTIES, INCLUDING, BUT
30 * NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND
31 * FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL
32 * EXOFFICE TECHNOLOGIES OR ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT,
33 * INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
34 * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
35 * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
36 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
37 * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
38 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED
39 * OF THE POSSIBILITY OF SUCH DAMAGE.
40 *
41 * Copyright 1999 (C) Exoffice Technologies Inc. All Rights Reserved.
42 *
43 * $Id: BaseLease.java,v 1.6 2003/08/17 01:32:24 tanderson Exp $
44 *
45 * Date Author Changes
46 * 2/29/2000 jima Created
47 */
48 package org.exolab.jms.lease;
49
50
51 import java.io.Serializable;
52
53
54 /***
55 * This is the implementation of a non-specific lease object. It can be used to
56 * lease any Objeect. .
57 *
58 * @version $Revision: 1.6 $ $Date: 2003/08/17 01:32:24 $
59 * @author <a href="mailto:jima@exoffice.com">Jim Alateras</a>
60 **/
61 public class BaseLease
62 implements LeaseIfc, Comparable, Serializable {
63
64 /***
65 * Default constructor for the Serailizable/Externalizable interface
66 */
67 public BaseLease() {
68 }
69
70 /***
71 * Construct an instance of this class with the specified objct, and duration
72 *
73 * @param object leased object
74 * @param duration duration of lease
75 * @param listener will get notified on lease events
76 */
77 public BaseLease(Object object, long duration, LeaseEventListenerIfc listener) {
78
79
80 if ((object == null) ||
81 (listener == null)) {
82 throw new IllegalArgumentException("object or listener cannot be null");
83 }
84
85 leasedObject_ = object;
86 duration_ = duration;
87 expiryTime_ = System.currentTimeMillis() + duration;
88 listener_ = listener;
89 }
90
91
92 public long getExpiryTime() {
93 return expiryTime_;
94 }
95
96
97 public long getDuration() {
98 return duration_;
99 }
100
101
102 public void setDuration(long duration) {
103 duration_ = duration;
104 expiryTime_ = System.currentTimeMillis() + duration;
105 }
106
107
108 public long getRemainingTime() {
109 return (System.currentTimeMillis() - expiryTime_);
110 }
111
112
113 public Object getLeasedObject() {
114 return leasedObject_;
115 }
116
117
118 public Class getLeasedObjectType() {
119 return leasedObject_.getClass();
120 }
121
122 /***
123 * Return a reference to the listener registered with this object
124 *
125 * @return LeaseEventListenerIfc
126 */
127 public LeaseEventListenerIfc getLeaseEventListener() {
128 return listener_;
129 }
130
131 /***
132 * Compares this object with the specified object. It returns a negative
133 * integer is this object is less than the specified object; zero if this
134 * object is equal to the specified object or a positive integer if this
135 * object is greater than the specified object
136 * <p>
137 * The comparison is based on the expiration time.
138 */
139 public int compareTo(Object object) {
140 int result = 0;
141
142 if (object instanceof BaseLease) {
143 BaseLease lease = (BaseLease) object;
144 if (lease.getExpiryTime() != this.getExpiryTime()) {
145 if (lease.getExpiryTime() > this.getExpiryTime()) {
146 result = -1;
147 } else {
148 result = 1;
149 }
150 }
151 }
152 return result;
153 }
154
155 /***
156 * Notify the listeners that this lease has expird. This method has
157 * package level scope.
158 */
159 void notifyLeaseExpired() {
160 synchronized (listener_) {
161 listener_.onLeaseExpired(leasedObject_);
162 }
163 }
164
165 /***
166 * Return a string representation of this object
167 *
168 * @return String
169 */
170 public String toString() {
171 StringBuffer buf = new StringBuffer(leasedObject_.toString());
172 buf.append(" duration = ");
173 buf.append(duration_);
174 buf.append(" expiryTime = ");
175 buf.append(expiryTime_);
176
177 return buf.toString();
178 }
179
180
181 /***
182 * This is the object that is leased
183 */
184 protected Object leasedObject_ = null;
185
186 /***
187 * The duration of the lease in milliseconds
188 */
189 protected long duration_ = 0L;
190
191 /***
192 * This is the time that the lease will expire
193 */
194 protected long expiryTime_ = 0L;
195
196 /***
197 * The listener that will be notified when the lease expires
198 */
199 protected LeaseEventListenerIfc listener_ = null;
200 }
201