001/* ===========================================================
002 * JFreeChart : a free chart library for the Java(tm) platform
003 * ===========================================================
004 *
005 * (C) Copyright 2000-2013, 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 * [Oracle and Java are registered trademarks of Oracle and/or its affiliates. 
025 * Other names may be trademarks of their respective owners.]
026 *
027 * --------------------
028 * VectorXYDataset.java
029 * --------------------
030 * (C) Copyright 2007, 2008, 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
045package org.jfree.data.xy;
046
047/**
048 * An extension of the {@link XYDataset} interface that allows a vector to be
049 * defined at a specific (x, y) location.
050 *
051 * @since 1.0.6
052 */
053public interface VectorXYDataset extends XYDataset {
054
055    /**
056     * Returns the x-component of the vector for an item in a series.
057     *
058     * @param series  the series index.
059     * @param item  the item index.
060     *
061     * @return The x-component of the vector.
062     */
063    public double getVectorXValue(int series, int item);
064
065    /**
066     * Returns the y-component of the vector for an item in a series.
067     *
068     * @param series  the series index.
069     * @param item  the item index.
070     *
071     * @return The y-component of the vector.
072     */
073    public double getVectorYValue(int series, int item);
074
075    /**
076     * Returns the vector for an item in a series.  Depending on the particular
077     * dataset implementation, this may involve creating a new {@link Vector}
078     * instance --- if you are just interested in the x and y components,
079     * use the {@link #getVectorXValue(int, int)} and
080     * {@link #getVectorYValue(int, int)} methods instead.
081     *
082     * @param series  the series index.
083     * @param item  the item index.
084     *
085     * @return The vector (possibly <code>null</code>).
086     */
087    public Vector getVector(int series, int item);
088
089}