1 /**
2 * JDBM LICENSE v1.00
3 *
4 * Redistribution and use of this software and associated documentation
5 * ("Software"), with or without modification, are permitted provided
6 * that the following conditions are met:
7 *
8 * 1. Redistributions of source code must retain copyright
9 * statements and notices. Redistributions must also contain a
10 * copy of this document.
11 *
12 * 2. Redistributions in binary form must reproduce the
13 * above copyright notice, this list of conditions and the
14 * following disclaimer in the documentation and/or other
15 * materials provided with the distribution.
16 *
17 * 3. The name "JDBM" must not be used to endorse or promote
18 * products derived from this Software without prior written
19 * permission of Cees de Groot. For written permission,
20 * please contact cg@cdegroot.com.
21 *
22 * 4. Products derived from this Software may not be called "JDBM"
23 * nor may "JDBM" appear in their names without prior written
24 * permission of Cees de Groot.
25 *
26 * 5. Due credit should be given to the JDBM Project
27 * (http://jdbm.sourceforge.net/).
28 *
29 * THIS SOFTWARE IS PROVIDED BY THE JDBM PROJECT AND CONTRIBUTORS
30 * ``AS IS'' AND ANY EXPRESSED OR IMPLIED WARRANTIES, INCLUDING, BUT
31 * NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND
32 * FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL
33 * CEES DE GROOT OR ANY CONTRIBUTORS BE LIABLE FOR ANY DIRECT,
34 * INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
35 * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
36 * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
37 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
38 * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
39 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED
40 * OF THE POSSIBILITY OF SUCH DAMAGE.
41 *
42 * Copyright 2001 (C) Alex Boisvert. All Rights Reserved.
43 * Contributions are Copyright (C) 2001 by their associated contributors.
44 *
45 */
46
47 package jdbm.helper;
48
49 import java.io.IOException;
50
51 /**
52 * Browser to traverse a collection of tuples. The browser allows for
53 * forward and reverse order traversal.
54 *
55 * @author <a href="mailto:boisvert@intalio.com">Alex Boisvert</a>
56 * @version $Id: TupleBrowser.java,v 1.2 2001/05/19 14:02:00 boisvert Exp $
57 */
58 public abstract class TupleBrowser {
59
60 /**
61 * Get the next tuple.
62 *
63 * @param tuple Tuple into which values are copied.
64 * @return True if values have been copied in tuple, or false if there is
65 * no next tuple.
66 */
67 public abstract boolean getNext( Tuple tuple )
68 throws IOException;
69
70
71 /**
72 * Get the previous tuple.
73 *
74 * @param tuple Tuple into which values are copied.
75 * @return True if values have been copied in tuple, or false if there is
76 * no previous tuple.
77 */
78 public abstract boolean getPrevious( Tuple tuple )
79 throws IOException;
80
81 }