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.cursor;
021    
022    
023    import java.util.Iterator;
024    
025    import org.apache.directory.shared.i18n.I18n;
026    
027    
028    /**
029     * An Iterator over a Cursor so Cursors can be Iterable for using in foreach
030     * constructs.
031     *
032     * @author <a href="mailto:dev@directory.apache.org">Apache Directory Project</a>
033     * @version $$Rev$$
034     */
035    public class CursorIterator<E> implements Iterator<E>
036    {
037        /** The inner cursor we will iterate */
038        private final Cursor<E> cursor;
039        
040        /** A flag used to store the cursor state */
041        private boolean available;
042    
043    
044        /**
045         * 
046         * Creates a new instance of CursorIterator.
047         *
048         * @param cursor The inner cursor
049         */
050        public CursorIterator( Cursor<E> cursor )
051        {
052            this.cursor = cursor;
053            this.available = cursor.available();
054        }
055    
056    
057        /**
058         * {@inheritDoc}
059         */
060        public boolean hasNext()
061        {
062            return available;
063        }
064    
065    
066        /**
067         * {@inheritDoc}
068         */
069        public E next()
070        {
071            try
072            {
073                E element = cursor.get();
074                available = cursor.next();
075                return element;
076            }
077            catch ( Exception e )
078            {
079                throw new RuntimeException( I18n.err( I18n.ERR_02002 ), e );
080            }
081        }
082    
083    
084        /**
085         * {@inheritDoc}
086         */
087        public void remove()
088        {
089            throw new UnsupportedOperationException( I18n.err( I18n.ERR_02003 ) );
090        }
091    }