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/**
* 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() {}
}