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 UUID. We simply use the UUID compareTo method.
030 *
031 * @author <a href="mailto:dev@directory.apache.org">Apache Directory Project</a>
032 * @version $Rev$
033 */
034 public class UUIDComparator extends LdapComparator<String>
035 {
036 /** A logger for this class */
037 private static final Logger LOG = LoggerFactory.getLogger( UUIDComparator.class );
038
039 /** The serialVersionUID */
040 private static final long serialVersionUID = 1L;
041
042 /**
043 * The UUIDComparator constructor. Its OID is the UUIDMatch matching
044 * rule OID.
045 */
046 public UUIDComparator( String oid )
047 {
048 super( oid );
049 }
050
051
052 /**
053 * @see java.util.Comparator#compare(java.lang.Object, java.lang.Object)
054 */
055 public int compare( String uuid1, String uuid2 )
056 {
057 LOG.debug( "comparing UUID objects '{}' with '{}'", uuid1, uuid2 );
058
059 // -------------------------------------------------------------------
060 // Handle some basis cases
061 // -------------------------------------------------------------------
062 if ( uuid1 == null )
063 {
064 return ( uuid2 == null ) ? 0 : -1;
065 }
066
067 if ( uuid2 == null )
068 {
069 return 1;
070 }
071
072 return uuid1.compareTo( uuid2 );
073 }
074 }