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
021package org.apache.directory.server.dns.io.decoder;
022
023
024import java.io.IOException;
025import java.util.HashMap;
026import java.util.Map;
027
028import org.apache.directory.api.util.Strings;
029import org.apache.directory.server.dns.store.DnsAttribute;
030import org.apache.mina.core.buffer.IoBuffer;
031
032
033/**
034 * A decoder for MX records.  MX records are encoded as per RFC-1035:
035 * 
036 * <pre>
037 *   3.3.9. MX RDATA format
038 *
039 *     +--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+
040 *     |                  PREFERENCE                   |
041 *     +--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+
042 *     /                   EXCHANGE                    /
043 *     /                                               /
044 *     +--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+
045 *
046 *   where:
047 *
048 *   PREFERENCE
049 *     A 16 bit integer which specifies the preference given to this RR among 
050 *     others at the same owner. Lower values are preferred. 
051 *     
052 *   EXCHANGE
053 *     A &lt;domain-name&gt; which specifies a host willing to act as a mail exchange
054 *     for the owner name.
055 * </pre>
056 * 
057 * @author <a href="mailto:dev@directory.apache.org">Apache Directory Project</a>
058 */
059public class MailExchangeRecordDecoder implements RecordDecoder
060{
061    public Map<String, Object> decode( IoBuffer byteBuffer, short length ) throws IOException
062    {
063        Map<String, Object> attributes = new HashMap<>();
064        attributes.put( Strings.toLowerCaseAscii( DnsAttribute.MX_PREFERENCE ), byteBuffer.getShort() );
065        attributes.put( Strings.toLowerCaseAscii( DnsAttribute.DOMAIN_NAME ), DnsMessageDecoder.getDomainName( byteBuffer ) );
066        
067        return attributes;
068    }
069}