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 */ 020package org.apache.directory.api.ldap.model.schema.comparators; 021 022 023import org.apache.directory.api.ldap.model.schema.LdapComparator; 024import org.apache.directory.api.util.Strings; 025import org.slf4j.Logger; 026import 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 */ 034public class ByteArrayComparator extends LdapComparator<byte[]> 035{ 036 /** The serial version UID */ 037 private static final long serialVersionUID = 2L; 038 039 /** A logger for this class */ 040 private static final Logger LOG = LoggerFactory.getLogger( ByteArrayComparator.class ); 041 042 043 /** 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 /** 054 * @see java.util.Comparator#compare(java.lang.Object, java.lang.Object) 055 */ 056 public int compare( byte[] b1, byte[] b2 ) 057 { 058 LOG.debug( "comparing OctetString objects '{}' with '{}'", 059 Strings.dumpBytes( b1 ), Strings.dumpBytes( b2 ) ); 060 061 // ------------------------------------------------------------------- 062 // Handle some basis cases 063 // ------------------------------------------------------------------- 064 065 if ( b1 == null ) 066 { 067 return ( b2 == null ) ? 0 : -1; 068 } 069 070 if ( b2 == null ) 071 { 072 return 1; 073 } 074 075 if ( b1.length == b2.length ) 076 { 077 for ( int i = 0; i < b1.length; i++ ) 078 { 079 if ( b1[i] > b2[i] ) 080 { 081 return 1; 082 } 083 else if ( b1[i] < b2[i] ) 084 { 085 return -1; 086 } 087 } 088 089 return 0; 090 } 091 092 int minLength = Math.min( b1.length, b2.length ); 093 094 for ( int i = 0; i < minLength; i++ ) 095 { 096 if ( b1[i] > b2[i] ) 097 { 098 return 1; 099 } 100 else if ( b1[i] < b2[i] ) 101 { 102 return -1; 103 } 104 } 105 106 // b2 is longer w/ b1 as prefix 107 if ( b1.length == minLength ) 108 { 109 return -1; 110 } 111 112 // b1 is longer w/ b2 as prefix 113 if ( b2.length == minLength ) 114 { 115 return 1; 116 } 117 118 return 0; 119 } 120}