    001    /* ===========================================================
    002     * JFreeChart : a free chart library for the Java(tm) platform
    003     * ===========================================================
    004     *
    005     * (C) Copyright 2000-2011, 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     * HeatMapUtilities.java
    029     * ---------------------
    030     * (C) Copyright 2009, by Object Refinery Limited.
    031     *
    032     * Original Author:  David Gilbert (for Object Refinery Limited);
    033     * Contributor(s):   -;
    034     *
    035     * Changes:
    036     * --------
    037     * 28-Jan-2009 : Version 1 (DG);
    038     *
    039     */
    040
    041    package org.jfree.data.general;
    042
    043    import java.awt.Graphics2D;
    044    import java.awt.Paint;
    045    import java.awt.image.BufferedImage;
    046    import org.jfree.chart.renderer.PaintScale;
    047    import org.jfree.data.xy.XYDataset;
    048    import org.jfree.data.xy.XYSeries;
    049    import org.jfree.data.xy.XYSeriesCollection;
    050
    051    /**
    052     * A utility class for the {@link HeatMapDataset}.
    053     *
    054     * @since 1.0.13
    055     */
    056    public abstract class HeatMapUtilities {
    057
    058        /**
    059         * Returns a dataset containing one series that holds a copy of the (x, z)
    060         * data from one row (y-index) of the specified dataset.
    061         *
    062         * @param dataset  the dataset (<code>null</code> not permitted).
    063         * @param row  the row (y) index.
    064         * @param seriesName  the series name/key (<code>null</code> not permitted).
    065         *
    066         * @return The dataset.
    067         */
    068        public static XYDataset extractRowFromHeatMapDataset(HeatMapDataset dataset,
    069                int row, Comparable seriesName) {
    070            XYSeries series = new XYSeries(seriesName);
    071            int cols = dataset.getXSampleCount();
    072            for (int c = 0; c < cols; c++) {
    073                series.add(dataset.getXValue(c), dataset.getZValue(c, row));
    074            }
    075            XYSeriesCollection result = new XYSeriesCollection(series);
    076            return result;
    077        }
    078
    079        /**
    080         * Returns a dataset containing one series that holds a copy of the (y, z)
    081         * data from one column (x-index) of the specified dataset.
    082         *
    083         * @param dataset  the dataset (<code>null</code> not permitted).
    084         * @param column  the column (x) index.
    085         * @param seriesName  the series name (<code>null</code> not permitted).
    086         *
    087         * @return The dataset.
    088         */
    089        public static XYDataset extractColumnFromHeatMapDataset(
    090                HeatMapDataset dataset, int column, Comparable seriesName) {
    091            XYSeries series = new XYSeries(seriesName);
    092            int rows = dataset.getYSampleCount();
    093            for (int r = 0; r < rows; r++) {
    094                series.add(dataset.getYValue(r), dataset.getZValue(column, r));
    095            }
    096            XYSeriesCollection result = new XYSeriesCollection(series);
    097            return result;
    098        }
    099
    100        /**
    101         * Creates an image that displays the values from the specified dataset.
    102         *
    103         * @param dataset  the dataset (<code>null</code> not permitted).
    104         * @param paintScale  the paint scale for the z-values (<code>null</code>
    105         *         not permitted).
    106         *
    107         * @return A buffered image.
    108         */
    109        public static BufferedImage createHeatMapImage(HeatMapDataset dataset,
    110                PaintScale paintScale) {
    111
    112            if (dataset == null) {
    113                throw new IllegalArgumentException("Null 'dataset' argument.");
    114            }
    115            if (paintScale == null) {
    116                throw new IllegalArgumentException("Null 'paintScale' argument.");
    117            }
    118            int xCount = dataset.getXSampleCount();
    119            int yCount = dataset.getYSampleCount();
    120            BufferedImage image = new BufferedImage(xCount, yCount,
    121                    BufferedImage.TYPE_INT_ARGB);
    122            Graphics2D g2 = image.createGraphics();
    123            for (int xIndex = 0; xIndex < xCount; xIndex++) {
    124                for (int yIndex = 0; yIndex < yCount; yIndex++) {
    125                    double z = dataset.getZValue(xIndex, yIndex);
    126                    Paint p = paintScale.getPaint(z);
    127                    g2.setPaint(p);
    128                    g2.fillRect(xIndex, yCount - yIndex - 1, 1, 1);
    129                }
    130            }
    131            return image;
    132        }
    133
    134    }