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.slf4j.Logger;
025    import org.slf4j.LoggerFactory;
026    
027    
028    /**
029     * A comparator for the objectIdentifierMatch matchingRule.
030     * 
031     * @author <a href="mailto:dev@directory.apache.org">Apache Directory Project</a>
032     * @version $Rev: 896579 $
033     */
034    public class ObjectIdentifierComparator extends LdapComparator<Object>
035    {
036        /** A logger for this class */
037        private static final Logger LOG = LoggerFactory.getLogger( ObjectIdentifierComparator.class );
038    
039        /** The serialVersionUID */
040        private static final long serialVersionUID = 1L;
041    
042        
043        /**
044         * The ObjectIdentifierComparator constructor. Its OID is the ObjectIdentifierMatch matching
045         * rule OID.
046         */
047        public ObjectIdentifierComparator( 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( Object o1, Object o2 )
057        {
058            LOG.debug( "comparing ObjectIdentifier objects '{}' with '{}'", o1, o2 );
059    
060            // -------------------------------------------------------------------
061            // Handle some basis cases
062            // -------------------------------------------------------------------
063            if ( o1 == null )
064            {
065                return ( o2 == null ) ? 0 : -1;
066            }
067            else if ( o2 == null )
068            {
069                return 1;
070            }
071    
072            if ( o1.equals( o2 ) )
073            {
074                return 0;
075            }
076    
077            if ( !( o1 instanceof String && o2 instanceof String ) )
078            {
079                if ( o1.equals( o2 ) )
080                {
081                    return 0;
082                }
083    
084                return -1;
085            }
086    
087            String s1 = ( ( String ) o1 ).trim().toLowerCase(), s2 = ( ( String ) o2 ).trim().toLowerCase();
088            return s1.compareTo( s2 );
089        }
090    }