001 /* 002 * Licensed to the Apache Software Foundation (ASF) under one 003 * or more contributor license agreements. See the NOTICE file 004 * distributed with this work for additional information 005 * regarding copyright ownership. The ASF licenses this file 006 * to you under the Apache License, Version 2.0 (the 007 * "License"); you may not use this file except in compliance 008 * with the License. You may obtain a copy of the License at 009 * 010 * http://www.apache.org/licenses/LICENSE-2.0 011 * 012 * Unless required by applicable law or agreed to in writing, 013 * software distributed under the License is distributed on an 014 * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY 015 * KIND, either express or implied. See the License for the 016 * specific language governing permissions and limitations 017 * under the License. 018 * 019 */ 020 package org.apache.directory.shared.ldap.schema.comparators; 021 022 023 import org.apache.directory.shared.ldap.schema.LdapComparator; 024 import org.apache.directory.shared.ldap.util.StringTools; 025 import org.slf4j.Logger; 026 import org.slf4j.LoggerFactory; 027 028 029 /** 030 * A comparator for byte[]s. 031 * 032 * @author <a href="mailto:dev@directory.apache.org">Apache Directory Project</a> 033 * @version $Rev$ 034 */ 035 public class ByteArrayComparator extends LdapComparator<byte[]> 036 { 037 /** A logger for this class */ 038 private static final Logger LOG = LoggerFactory.getLogger( ByteArrayComparator.class ); 039 040 /** The serialVersionUID */ 041 private static final long serialVersionUID = 1L; 042 043 /** 044 * The ByteArrayComparator constructor. Its OID is the OctetStringMatch matching 045 * rule OID. 046 */ 047 public ByteArrayComparator( String oid ) 048 { 049 super( oid ); 050 } 051 052 /** 053 * @see java.util.Comparator#compare(java.lang.Object, java.lang.Object) 054 */ 055 public int compare( byte[] b1, byte[] b2 ) 056 { 057 LOG.debug( "comparing OctetString objects '{}' with '{}'", 058 StringTools.dumpBytes( b1 ), StringTools.dumpBytes( b2 ) ); 059 060 // ------------------------------------------------------------------- 061 // Handle some basis cases 062 // ------------------------------------------------------------------- 063 064 if ( b1 == null ) 065 { 066 return ( b2 == null ) ? 0 : -1; 067 } 068 069 if ( b2 == null ) 070 { 071 return 1; 072 } 073 074 if ( b1.length == b2.length ) 075 { 076 for ( int i = 0; i < b1.length; i++ ) 077 { 078 if ( b1[i] > b2[i] ) 079 { 080 return 1; 081 } 082 else if ( b1[i] < b2[i] ) 083 { 084 return -1; 085 } 086 } 087 088 return 0; 089 } 090 091 int minLength = Math.min( b1.length, b2.length ); 092 093 for ( int i = 0; i < minLength; i++ ) 094 { 095 if ( b1[i] > b2[i] ) 096 { 097 return 1; 098 } 099 else if ( b1[i] < b2[i] ) 100 { 101 return -1; 102 } 103 } 104 105 // b2 is longer w/ b1 as prefix 106 if ( b1.length == minLength ) 107 { 108 return -1; 109 } 110 111 // b1 is longer w/ b2 as prefix 112 if ( b2.length == minLength ) 113 { 114 return 1; 115 } 116 117 return 0; 118 } 119 }