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 java.util.Comparator;
024    
025    
026    /**
027     * A comparator for TelephoneNumber.
028     * 
029     * The rules for matching are identical to those for caseIgnoreMatch, except that 
030     * all space and "-" characters are skipped during the comparison. 
031     * 
032     * @author <a href="mailto:dev@directory.apache.org">Apache Directory Project</a>
033     * @version $Rev$
034     */
035    public class TelephoneNumberComparator implements Comparator<String>
036    {
037        /** A static instance of this comparator */
038        public static final Comparator<String> INSTANCE = new TelephoneNumberComparator();
039        
040        
041        /**
042         * Remove all spaces and '-' from the telephone number
043         */
044        private String strip( String telephoneNumber )
045        {
046            char[] telephoneNumberArray = telephoneNumber.toCharArray();
047            int pos = 0;
048            
049            for ( char c:telephoneNumberArray )
050            {
051                if ( ( c == ' ' ) || ( c == '-' ) )
052                { 
053                    continue;
054                }
055                
056                telephoneNumberArray[pos++] = c;
057            }
058            
059            return new String( telephoneNumberArray, 0, pos );
060        }
061    
062        
063        /**
064         * @see java.util.Comparator#compare(java.lang.Object, java.lang.Object)
065         */
066        public int compare( String telephoneNumber1, String telephoneNumber2 )
067        {
068            // -------------------------------------------------------------------
069            // Handle some basis cases
070            // -------------------------------------------------------------------
071    
072            if ( telephoneNumber1 == null )
073            {
074                return ( telephoneNumber2 == null ) ? 0 : -1;
075            }
076            
077            if ( telephoneNumber2 == null )
078            {
079                return 1;
080            }
081            
082            // -------------------------------------------------------------------
083            // Remove all spaces and '-'
084            // -------------------------------------------------------------------
085            telephoneNumber1 = strip( telephoneNumber1 );
086            telephoneNumber2 = strip( telephoneNumber2 );
087            
088            return ( telephoneNumber1.compareToIgnoreCase( telephoneNumber2 ) );
089        }
090    }