1 /** 2 * JDBM LICENSE v1.00 3 * 4 * Redistribution and use of this software and associated documentation 5 * ("Software"), with or without modification, are permitted provided 6 * that the following conditions are met: 7 * 8 * 1. Redistributions of source code must retain copyright 9 * statements and notices. Redistributions must also contain a 10 * copy of this document. 11 * 12 * 2. Redistributions in binary form must reproduce the 13 * above copyright notice, this list of conditions and the 14 * following disclaimer in the documentation and/or other 15 * materials provided with the distribution. 16 * 17 * 3. The name "JDBM" must not be used to endorse or promote 18 * products derived from this Software without prior written 19 * permission of Cees de Groot. For written permission, 20 * please contact cg@cdegroot.com. 21 * 22 * 4. Products derived from this Software may not be called "JDBM" 23 * nor may "JDBM" appear in their names without prior written 24 * permission of Cees de Groot. 25 * 26 * 5. Due credit should be given to the JDBM Project 27 * (http://jdbm.sourceforge.net/). 28 * 29 * THIS SOFTWARE IS PROVIDED BY THE JDBM PROJECT AND CONTRIBUTORS 30 * ``AS IS'' AND ANY EXPRESSED OR IMPLIED WARRANTIES, INCLUDING, BUT 31 * NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND 32 * FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL 33 * CEES DE GROOT OR ANY CONTRIBUTORS BE LIABLE FOR ANY DIRECT, 34 * INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES 35 * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR 36 * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 37 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, 38 * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) 39 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED 40 * OF THE POSSIBILITY OF SUCH DAMAGE. 41 * 42 * Copyright 2001 (C) Alex Boisvert. All Rights Reserved. 43 * Contributions are Copyright (C) 2001 by their associated contributors. 44 * 45 */ 46 47 package jdbm.helper; 48 49 import java.io.Serializable; 50 import java.util.Comparator; 51 52 /** 53 * Comparator for Integer objects. 54 * 55 * @author <a href="mailto:cdaller@iicm.edu">Christof Dallermassl</a> 56 * @version $Id: IntegerComparator.java,v 1.2 2002/05/31 06:33:20 boisvert Exp $ 57 */ 58 public final class IntegerComparator 59 implements Comparator, Serializable 60 { 61 62 /** 63 * Version id for serialization. 64 */ 65 final static long serialVersionUID = 1L; 66 67 68 /** 69 * Compare two objects. 70 * 71 * @param obj1 First object 72 * @param obj2 Second object 73 * @return a positive integer if obj1 > obj2, 0 if obj1 == obj2, 74 * and a negative integer if obj1 < obj2 75 */ 76 public int compare( Object obj1, Object obj2 ) 77 { 78 if ( obj1 == obj2 ) { 79 return 0; 80 } 81 82 if ( obj1 == null ) { 83 throw new IllegalArgumentException( "Argument 'obj1' is null" ); 84 } 85 86 if ( obj2 == null ) { 87 throw new IllegalArgumentException( "Argument 'obj2' is null" ); 88 } 89 90 // complicated to avoid usage of Integer.compareTo, as this 91 // method is Java 1.2 only! 92 int int1 = ( (Integer) obj1 ).intValue(); 93 int int2 = ( (Integer) obj2 ).intValue(); 94 if ( int1 == int2 ) { 95 return 0; 96 } 97 98 if ( int1 < int2 ) { 99 return -1; 100 } else { 101 return 1; 102 } 103 } 104 105 }