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.server.core.partition.impl.btree;
021    
022    
023    import java.util.Iterator;
024    
025    import org.apache.directory.server.xdbm.IndexCursor;
026    import org.apache.directory.server.xdbm.IndexEntry;
027    import org.apache.directory.shared.ldap.cursor.ClosureMonitor;
028    import org.apache.directory.shared.ldap.cursor.Cursor;
029    import org.apache.directory.shared.ldap.cursor.CursorIterator;
030    import org.apache.directory.shared.ldap.entry.ServerEntry;
031    
032    
033    /**
034     * Adapts index cursors to return just ServerEntry objects.
035     *
036     * @author <a href="mailto:dev@directory.apache.org">Apache Directory Project</a>
037     * @version $Rev$, $Date$
038     */
039    public class ServerEntryCursorAdaptor<ID> implements Cursor<ServerEntry>
040    {
041        private final BTreePartition<ID> db;
042        private final IndexCursor<ID, ServerEntry, ID> indexCursor;
043    
044    
045        public ServerEntryCursorAdaptor( BTreePartition<ID> db, IndexCursor<ID, ServerEntry, ID> indexCursor )
046        {
047            this.db = db;
048            this.indexCursor = indexCursor;
049        }
050    
051    
052        /* 
053         * @see Cursor#after(java.lang.Object)
054         */
055        public void after( ServerEntry element ) throws Exception
056        {
057            throw new UnsupportedOperationException();
058        }
059    
060    
061        /* 
062         * @see Cursor#afterLast()
063         */
064        public void afterLast() throws Exception
065        {
066            this.indexCursor.afterLast();
067        }
068    
069    
070        /* 
071         * @see Cursor#available()
072         */
073        public boolean available()
074        {
075            return indexCursor.available();
076        }
077    
078    
079        /* 
080         * @see Cursor#before(java.lang.Object)
081         */
082        public void before( ServerEntry element ) throws Exception
083        {
084            throw new UnsupportedOperationException();
085        }
086    
087    
088        /* 
089         * @see Cursor#beforeFirst()
090         */
091        public void beforeFirst() throws Exception
092        {
093            indexCursor.beforeFirst();
094        }
095    
096    
097        public final void setClosureMonitor( ClosureMonitor monitor )
098        {
099            indexCursor.setClosureMonitor( monitor );
100        }
101    
102    
103        /* 
104         * @see Cursor#close()
105         */
106        public void close() throws Exception
107        {
108            indexCursor.close();
109        }
110    
111    
112        /* 
113         * @see Cursor#close()
114         */
115        public void close( Exception e ) throws Exception
116        {
117            indexCursor.close( e );
118        }
119    
120    
121        /* 
122         * @see Cursor#first()
123         */
124        public boolean first() throws Exception
125        {
126            return indexCursor.first();
127        }
128    
129    
130        /* 
131         * @see Cursor#get()
132         */
133        public ServerEntry get() throws Exception
134        {
135            IndexEntry<ID, ServerEntry, ID> indexEntry = indexCursor.get();
136    
137            if ( indexEntry.getObject() == null )
138            {
139                indexEntry.setObject( db.lookup( indexEntry.getId() ) );
140            }
141    
142            return indexEntry.getObject();
143        }
144    
145    
146        /* 
147         * @see Cursor#isClosed()
148         */
149        public boolean isClosed() throws Exception
150        {
151            return indexCursor.isClosed();
152        }
153    
154    
155        /* 
156         * @see Cursor#isElementReused()
157         */
158        public boolean isElementReused()
159        {
160            return indexCursor.isElementReused();
161        }
162    
163    
164        /* 
165         * @see Cursor#last()
166         */
167        public boolean last() throws Exception
168        {
169            return indexCursor.last();
170        }
171    
172    
173        /* 
174         * @see Cursor#next()
175         */
176        public boolean next() throws Exception
177        {
178            return indexCursor.next();
179        }
180    
181    
182        /* 
183         * @see Cursor#previous()
184         */
185        public boolean previous() throws Exception
186        {
187            return indexCursor.previous();
188        }
189    
190    
191        /* 
192         * @see Iterable#iterator()
193         */
194        public Iterator<ServerEntry> iterator()
195        {
196            return new CursorIterator<ServerEntry>( this );
197        }
198    }