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.codec.search;
021    
022    
023    import java.nio.BufferOverflowException;
024    import java.nio.ByteBuffer;
025    import java.util.ArrayList;
026    import java.util.List;
027    
028    import org.apache.directory.shared.asn1.ber.tlv.TLV;
029    import org.apache.directory.shared.asn1.ber.tlv.Value;
030    import org.apache.directory.shared.asn1.codec.EncoderException;
031    import org.apache.directory.shared.ldap.codec.LdapConstants;
032    import org.apache.directory.shared.ldap.codec.LdapMessageCodec;
033    import org.apache.directory.shared.ldap.util.LdapURL;
034    
035    
036    /**
037     * A SearchResultReference Message. Its syntax is : 
038     * 
039     * SearchResultReference ::= [APPLICATION 19] SEQUENCE OF LDAPURL
040     * 
041     * @author <a href="mailto:dev@directory.apache.org">Apache Directory Project</a>
042     * @version $Rev: 764131 $, $Date: 2009-04-11 03:03:00 +0200 (Sam, 11 avr 2009) $, 
043     */
044    public class SearchResultReferenceCodec extends LdapMessageCodec
045    {
046        // ~ Instance fields
047        // ----------------------------------------------------------------------------
048    
049        /** The set of LdapURLs */
050        private List<LdapURL> searchResultReferences = new ArrayList<LdapURL>();
051    
052        /** The search result reference length */
053        private int searchResultReferenceLength;
054    
055    
056        // ~ Constructors
057        // -------------------------------------------------------------------------------
058    
059        /**
060         * Creates a new SearchResultEntry object.
061         */
062        public SearchResultReferenceCodec()
063        {
064            super();
065        }
066    
067    
068        // ~ Methods
069        // ------------------------------------------------------------------------------------
070    
071        /**
072         * Get the message type
073         * 
074         * @return Returns the type.
075         */
076        public int getMessageType()
077        {
078            return LdapConstants.SEARCH_RESULT_REFERENCE;
079        }
080    
081    
082        /**
083         * Add a new reference to the list.
084         * 
085         * @param searchResultReference The search result reference
086         */
087        public void addSearchResultReference( LdapURL searchResultReference )
088        {
089            searchResultReferences.add( searchResultReference );
090        }
091    
092    
093        /**
094         * Get the list of references
095         * 
096         * @return An ArrayList of SearchResultReferences
097         */
098        public List<LdapURL> getSearchResultReferences()
099        {
100            return searchResultReferences;
101        }
102    
103    
104        /**
105         * Compute the SearchResultReference length
106         * 
107         * SearchResultReference :
108         * 
109         * 0x73 L1
110         *  |
111         *  +--> 0x04 L2 reference
112         *  +--> 0x04 L3 reference
113         *  +--> ...
114         *  +--> 0x04 Li reference
115         *  +--> ...
116         *  +--> 0x04 Ln reference
117         * 
118         * L1 = n*Length(0x04) + sum(Length(Li)) + sum(Length(reference[i]))
119         * 
120         * Length(SearchResultReference) = Length(0x73 + Length(L1) + L1
121         */
122        public int computeLength()
123        {
124            searchResultReferenceLength = 0;
125    
126            // We may have more than one reference.
127            for ( LdapURL url:searchResultReferences )
128            {
129                int ldapUrlLength = url.getNbBytes();
130                searchResultReferenceLength += 1 + TLV.getNbBytes( ldapUrlLength ) + ldapUrlLength;
131            }
132    
133            return 1 + TLV.getNbBytes( searchResultReferenceLength ) + searchResultReferenceLength;
134        }
135    
136    
137        /**
138         * Encode the SearchResultReference message to a PDU.
139         * 
140         * SearchResultReference :
141         * 
142         * 0x73 LL
143         *   0x04 LL reference
144         *   [0x04 LL reference]*
145         * 
146         * @param buffer The buffer where to put the PDU
147         * @return The PDU.
148         */
149        public ByteBuffer encode( ByteBuffer buffer ) throws EncoderException
150        {
151            if ( buffer == null )
152            {
153                throw new EncoderException( "Cannot put a PDU in a null buffer !" );
154            }
155    
156            try
157            {
158                // The SearchResultReference Tag
159                buffer.put( LdapConstants.SEARCH_RESULT_REFERENCE_TAG );
160                buffer.put( TLV.getBytes( searchResultReferenceLength ) );
161    
162                // The references. We must at least have one reference
163                for ( LdapURL reference:searchResultReferences )
164                {
165                    // Encode the reference
166                    Value.encode( buffer, reference.getString() );
167                }
168            }
169            catch ( BufferOverflowException boe )
170            {
171                throw new EncoderException( "The PDU buffer size is too small !" );
172            }
173    
174            return buffer;
175        }
176    
177    
178        /**
179         * Returns the Search Result Reference string
180         * 
181         * @return The Search Result Reference string
182         */
183        public String toString()
184        {
185    
186            StringBuffer sb = new StringBuffer();
187    
188            sb.append( "    Search Result Reference\n" );
189    
190            if ( ( searchResultReferences == null ) || ( searchResultReferences.size() == 0 ) )
191            {
192                sb.append( "        No Reference\n" );
193            }
194            else
195            {
196                sb.append( "        References\n" );
197    
198                for ( LdapURL url:searchResultReferences )
199                {
200                    sb.append( "            '" ).append( url ).append(
201                        "'\n" );
202                }
203            }
204    
205            return sb.toString();
206        }
207    }