/*
 *  Licensed to the Apache Software Foundation (ASF) under one
 *  or more contributor license agreements.  See the NOTICE file
 *  distributed with this work for additional information
 *  regarding copyright ownership.  The ASF licenses this file
 *  to you under the Apache License, Version 2.0 (the
 *  "License"); you may not use this file except in compliance
 *  with the License.  You may obtain a copy of the License at
 *  
 *    http://www.apache.org/licenses/LICENSE-2.0
 *  
 *  Unless required by applicable law or agreed to in writing,
 *  software distributed under the License is distributed on an
 *  "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
 *  KIND, either express or implied.  See the License for the
 *  specific language governing permissions and limitations
 *  under the License. 
 *  
 */
package org.apache.directory.server.core.partition.impl.btree;


import javax.naming.NamingException;


/**
 * TupleBrowser interface used to abstract 
 * 
 * @author <a href="mailto:dev@directory.apache.org">Apache Directory Project</a>
 * @version $Rev$
 */
public interface TupleBrowser
{
    /**
     * Gets the next value deemed greater than the last using the key 
     * comparator.
     *
     * @param tuple the tuple to populate with a key/value pair
     * @return true if there was a next that was populated or false otherwise
     * @throws NamingException @todo
     */
    boolean getNext( Tuple tuple ) throws NamingException;


    /**
     * Gets the previous value deemed greater than the last using the key 
     * comparator.
     *
     * @param tuple the tuple to populate with a key/value pair
     * @return true if there was a previous value populated or false otherwise
     * @throws NamingException @todo
     */
    boolean getPrevious( Tuple tuple ) throws NamingException;
}