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.slf4j.Logger;
025import org.slf4j.LoggerFactory;
026
027
028/**
029 * A comparator for CSN SID.
030 *
031 * The SID is supposed to be an hexadecimal number between 0x0 and 0xfff
032 * 
033 * @author <a href="mailto:dev@directory.apache.org">Apache Directory Project</a>
034 */
035public class CsnSidComparator extends LdapComparator<String>
036{
037    /** The serial version UID */
038    private static final long serialVersionUID = 2L;
039
040    /** A logger for this class */
041    private static final Logger LOG = LoggerFactory.getLogger( CsnSidComparator.class );
042
043    /**
044     * The CsnSidComparator constructor. Its OID is the CsnSidMatch matching
045     * rule OID.
046     */
047    public CsnSidComparator( 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( String sidStr1, String sidStr2 )
057    {
058        LOG.debug( "comparing CSN SID objects '{}' with '{}'", sidStr1, sidStr2 );
059
060        // -------------------------------------------------------------------
061        // Handle some basis cases
062        // -------------------------------------------------------------------
063        if ( sidStr1 == null )
064        {
065            return ( sidStr2 == null ) ? 0 : -1;
066        }
067        
068        if ( sidStr2 == null )
069        {
070            return 1;
071        }
072        
073        int sid1 = 0;
074        int sid2 = 0;
075        
076        try
077        {
078            sid1 = Integer.parseInt( sidStr1, 16 );
079        }
080        catch ( NumberFormatException nfe )
081        {
082            return -1;
083        }
084        
085        try
086        {
087            sid2 = Integer.parseInt( sidStr2, 16 );
088        }
089        catch ( NumberFormatException nfe )
090        {
091            return 1;
092        }
093        
094        if ( sid1 > sid2 )
095        {
096            return 1;
097        }
098        else if ( sid2 > sid1 )
099        {
100            return -1;
101        }
102        
103        return 0;
104    }
105}