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.shared.ldap.model.schema.comparators; 021 022 023import org.apache.directory.shared.ldap.model.schema.LdapComparator; 024import org.apache.directory.shared.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 * The ByteArrayComparator constructor. Its OID is the OctetStringMatch matching 044 * rule OID. 045 */ 046 public ByteArrayComparator( String oid ) 047 { 048 super( oid ); 049 } 050 051 /** 052 * @see java.util.Comparator#compare(java.lang.Object, java.lang.Object) 053 */ 054 public int compare( byte[] b1, byte[] b2 ) 055 { 056 LOG.debug( "comparing OctetString objects '{}' with '{}'", 057 Strings.dumpBytes(b1), Strings.dumpBytes(b2) ); 058 059 // ------------------------------------------------------------------- 060 // Handle some basis cases 061 // ------------------------------------------------------------------- 062 063 if ( b1 == null ) 064 { 065 return ( b2 == null ) ? 0 : -1; 066 } 067 068 if ( b2 == null ) 069 { 070 return 1; 071 } 072 073 if ( b1.length == b2.length ) 074 { 075 for ( int i = 0; i < b1.length; i++ ) 076 { 077 if ( b1[i] > b2[i] ) 078 { 079 return 1; 080 } 081 else if ( b1[i] < b2[i] ) 082 { 083 return -1; 084 } 085 } 086 087 return 0; 088 } 089 090 int minLength = Math.min( b1.length, b2.length ); 091 092 for ( int i = 0; i < minLength; i++ ) 093 { 094 if ( b1[i] > b2[i] ) 095 { 096 return 1; 097 } 098 else if ( b1[i] < b2[i] ) 099 { 100 return -1; 101 } 102 } 103 104 // b2 is longer w/ b1 as prefix 105 if ( b1.length == minLength ) 106 { 107 return -1; 108 } 109 110 // b1 is longer w/ b2 as prefix 111 if ( b2.length == minLength ) 112 { 113 return 1; 114 } 115 116 return 0; 117 } 118}