1 /* ============================================================
2 * JRobin : Pure java implementation of RRDTool's functionality
3 * ============================================================
4 *
5 * Project Info: http://www.jrobin.org
6 * Project Lead: Sasa Markovic (saxon@jrobin.org)
7 *
8 * Developers: Sasa Markovic (saxon@jrobin.org)
9 *
10 *
11 * (C) Copyright 2003-2005, by Sasa Markovic.
12 *
13 * This library is free software; you can redistribute it and/or modify it under the terms
14 * of the GNU Lesser General Public License as published by the Free Software Foundation;
15 * either version 2.1 of the License, or (at your option) any later version.
16 *
17 * This library is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY;
18 * without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
19 * See the GNU Lesser General Public License for more details.
20 *
21 * You should have received a copy of the GNU Lesser General Public License along with this
22 * library; if not, write to the Free Software Foundation, Inc., 59 Temple Place, Suite 330,
23 * Boston, MA 02111-1307, USA.
24 */
25 package org.jrobin.data;
26
27 /**
28 * <p>Interface to be used for custom datasources.
29 * If you wish to use a custom datasource in a graph, you should create a class implementing this interface
30 * that represents that datasource, and then pass this class on to the RrdGraphDef.</p>
31 */
32 public abstract class Plottable {
33 /**
34 * Retrieves datapoint value based on a given timestamp.
35 * Use this method if you only have one series of data in this class.
36 *
37 * @param timestamp Timestamp in seconds for the datapoint.
38 * @return Double value of the datapoint.
39 */
40 public double getValue(long timestamp) {
41 return Double.NaN;
42 }
43 }