001 /* ===========================================================
002 * JFreeChart : a free chart library for the Java(tm) platform
003 * ===========================================================
004 *
005 * (C) Copyright 2000-2007, by Object Refinery Limited and Contributors.
006 *
007 * Project Info: http://www.jfree.org/jfreechart/index.html
008 *
009 * This library is free software; you can redistribute it and/or modify it
010 * under the terms of the GNU Lesser General Public License as published by
011 * the Free Software Foundation; either version 2.1 of the License, or
012 * (at your option) any later version.
013 *
014 * This library is distributed in the hope that it will be useful, but
015 * WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
016 * or FITNESS FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public
017 * License for more details.
018 *
019 * You should have received a copy of the GNU Lesser General Public
020 * License along with this library; if not, write to the Free Software
021 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301,
022 * USA.
023 *
024 * [Java is a trademark or registered trademark of Sun Microsystems, Inc.
025 * in the United States and other countries.]
026 *
027 * --------------------
028 * VectorXYDataset.java
029 * --------------------
030 * (C) Copyright 2007, by Object Refinery Limited and Contributors.
031 *
032 * Original Author: David Gilbert (for Object Refinery Limited);
033 * Contributor(s): -;
034 *
035 * Changes
036 * -------
037 * 30-Jan-2007 : Version 1 (DG);
038 * 24-May-2007 : Renamed getDeltaXValue() as getVectorXValue(), and likewise
039 * for getDeltaYValue(), and replaced getDeltaX()/getDeltaY()
040 * with getVector() (DG);
041 * 25-May-2007 : Moved from experimental to the main source tree (DG);
042 *
043 */
044
045 package org.jfree.data.xy;
046
047
048
049 /**
050 * An extension of the {@link XYDataset} interface that allows a vector to be
051 * defined at a specific (x, y) location.
052 *
053 * @since 1.0.6
054 */
055 public interface VectorXYDataset extends XYDataset {
056
057 /**
058 * Returns the x-component of the vector for an item in a series.
059 *
060 * @param series the series index.
061 * @param item the item index.
062 *
063 * @return The x-component of the vector.
064 */
065 public double getVectorXValue(int series, int item);
066
067 /**
068 * Returns the y-component of the vector for an item in a series.
069 *
070 * @param series the series index.
071 * @param item the item index.
072 *
073 * @return The y-component of the vector.
074 */
075 public double getVectorYValue(int series, int item);
076
077 /**
078 * Returns the vector for an item in a series. Depending on the particular
079 * dataset implementation, this may involve creating a new {@link Vector}
080 * instance --- if you are just interested in the x and y components,
081 * use the {@link #getVectorXValue(int, int)} and
082 * {@link #getVectorYValue(int, int)} methods instead.
083 *
084 * @param series the series index.
085 * @param item the item index.
086 *
087 * @return The vector (possibly <code>null</code>).
088 */
089 public Vector getVector(int series, int item);
090
091 }