| /** |
| * JDBM LICENSE v1.00 |
| * |
| * Redistribution and use of this software and associated documentation |
| * ("Software"), with or without modification, are permitted provided |
| * that the following conditions are met: |
| * |
| * 1. Redistributions of source code must retain copyright |
| * statements and notices. Redistributions must also contain a |
| * copy of this document. |
| * |
| * 2. Redistributions in binary form must reproduce the |
| * above copyright notice, this list of conditions and the |
| * following disclaimer in the documentation and/or other |
| * materials provided with the distribution. |
| * |
| * 3. The name "JDBM" must not be used to endorse or promote |
| * products derived from this Software without prior written |
| * permission of Cees de Groot. For written permission, |
| * please contact cg@cdegroot.com. |
| * |
| * 4. Products derived from this Software may not be called "JDBM" |
| * nor may "JDBM" appear in their names without prior written |
| * permission of Cees de Groot. |
| * |
| * 5. Due credit should be given to the JDBM Project |
| * (http://jdbm.sourceforge.net/). |
| * |
| * THIS SOFTWARE IS PROVIDED BY THE JDBM PROJECT AND CONTRIBUTORS |
| * ``AS IS'' AND ANY EXPRESSED OR IMPLIED WARRANTIES, INCLUDING, BUT |
| * NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND |
| * FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL |
| * CEES DE GROOT OR ANY CONTRIBUTORS BE LIABLE FOR ANY DIRECT, |
| * INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES |
| * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR |
| * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) |
| * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, |
| * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) |
| * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED |
| * OF THE POSSIBILITY OF SUCH DAMAGE. |
| * |
| * Copyright 2001 (C) Alex Boisvert. All Rights Reserved. |
| * Contributions are Copyright (C) 2001 by their associated contributors. |
| * |
| */ |
| |
| package jdbm.helper; |
| |
| import java.io.IOException; |
| |
| /** |
| * Browser to traverse a collection of tuples. The browser allows for |
| * forward and reverse order traversal. |
| * |
| * @author <a href="mailto:boisvert@intalio.com">Alex Boisvert</a> |
| */ |
| public abstract class TupleBrowser<K, V> { |
| /** |
| * Get the next tuple. |
| * |
| * @param tuple Tuple into which values are copied. |
| * @return True if values have been copied in tuple, or false if there is |
| * no next tuple. |
| */ |
| public abstract boolean getNext( Tuple<K, V> tuple ) throws IOException; |
| |
| |
| /** |
| * Get the previous tuple. |
| * |
| * @param tuple Tuple into which values are copied. |
| * @return True if values have been copied in tuple, or false if there is |
| * no previous tuple. |
| */ |
| public abstract boolean getPrevious( Tuple<K, V> tuple ) throws IOException; |
| |
| /** |
| * Closes the browser and deallocates any resources it might have allocated. |
| * Repeated calls of close are OK. |
| */ |
| public void close() {} |
| |
| } |