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: LeaseComparator.java,v 1.1 2004/11/26 01:50:42 tanderson Exp $
44 *
45 * Date Author Changes
46 * 3/01/2000 jima Created
47 */
48 package org.exolab.jms.lease;
49
50 import java.util.Comparator;
51
52
53 /***
54 * The LeaseComparator is usedto sort leases based on the expiration
55 * time
56 *
57 * @version $Revision: 1.1 $ $Date: 2004/11/26 01:50:42 $
58 * @author <a href="mailto:jima@exoffice.com">Jim Alateras</a>
59 **/
60 public class LeaseComparator
61 implements Comparator {
62
63 /***
64 * Compare two objects and return 0 if they are equal, a negative integer
65 * if the first argument is less than the second argument and a positive
66 * number if the first argument is greater than the second argument
67 * <p>
68 * It will throw ClassCastException if either obj1 or obj2 are not of type
69 * BaseLease
70 *
71 * @param obj1 first object to compare
72 * @param obj2 second object to compare
73 * @return int
74 */
75 public int compare(Object obj1, Object obj2) {
76 int result = 0;
77
78 if ((obj1 instanceof BaseLease) &&
79 (obj2 instanceof BaseLease)) {
80 BaseLease lease1 = (BaseLease) obj1;
81 BaseLease lease2 = (BaseLease) obj2;
82
83 if (lease1.getExpiryTime() != lease2.getExpiryTime()) {
84 if (lease1.getExpiryTime() < lease2.getExpiryTime()) {
85 result = -1;
86 } else {
87 result = 1;
88 }
89 }
90 } else {
91 throw new ClassCastException("obj1 is of type " +
92 obj1.getClass().getName() + " obj2 is of type " +
93 obj2.getClass().getName());
94 }
95
96 return result;
97 }
98
99 /***
100 * Return true if the specified comparator matches this object and
101 * false otherwise
102 *
103 * @param comparator comparator to test
104 * @return boolean true if they are the same
105 */
106 public boolean equals(Object comparator) {
107 return comparator instanceof LeaseComparator;
108 }
109 }
110
111