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 * HeatMapUtilities.java
029 * ---------------------
030 * (C) Copyright 2009-2013, 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 * 03-Jul-2013 : Use ParamChecks (DG);
039 *
040 */
041
042package org.jfree.data.general;
043
044import java.awt.Graphics2D;
045import java.awt.Paint;
046import java.awt.image.BufferedImage;
047import org.jfree.chart.renderer.PaintScale;
048import org.jfree.chart.util.ParamChecks;
049import org.jfree.data.xy.XYDataset;
050import org.jfree.data.xy.XYSeries;
051import org.jfree.data.xy.XYSeriesCollection;
052
053/**
054 * A utility class for the {@link HeatMapDataset}.
055 *
056 * @since 1.0.13
057 */
058public abstract class HeatMapUtilities {
059
060    /**
061     * Returns a dataset containing one series that holds a copy of the (x, z)
062     * data from one row (y-index) of the specified dataset.
063     *
064     * @param dataset  the dataset (<code>null</code> not permitted).
065     * @param row  the row (y) index.
066     * @param seriesName  the series name/key (<code>null</code> not permitted).
067     *
068     * @return The dataset.
069     */
070    public static XYDataset extractRowFromHeatMapDataset(HeatMapDataset dataset,
071            int row, Comparable seriesName) {
072        XYSeries series = new XYSeries(seriesName);
073        int cols = dataset.getXSampleCount();
074        for (int c = 0; c < cols; c++) {
075            series.add(dataset.getXValue(c), dataset.getZValue(c, row));
076        }
077        XYSeriesCollection result = new XYSeriesCollection(series);
078        return result;
079    }
080
081    /**
082     * Returns a dataset containing one series that holds a copy of the (y, z)
083     * data from one column (x-index) of the specified dataset.
084     *
085     * @param dataset  the dataset (<code>null</code> not permitted).
086     * @param column  the column (x) index.
087     * @param seriesName  the series name (<code>null</code> not permitted).
088     *
089     * @return The dataset.
090     */
091    public static XYDataset extractColumnFromHeatMapDataset(
092            HeatMapDataset dataset, int column, Comparable seriesName) {
093        XYSeries series = new XYSeries(seriesName);
094        int rows = dataset.getYSampleCount();
095        for (int r = 0; r < rows; r++) {
096            series.add(dataset.getYValue(r), dataset.getZValue(column, r));
097        }
098        XYSeriesCollection result = new XYSeriesCollection(series);
099        return result;
100    }
101
102    /**
103     * Creates an image that displays the values from the specified dataset.
104     *
105     * @param dataset  the dataset (<code>null</code> not permitted).
106     * @param paintScale  the paint scale for the z-values (<code>null</code>
107     *         not permitted).
108     *
109     * @return A buffered image.
110     */
111    public static BufferedImage createHeatMapImage(HeatMapDataset dataset,
112            PaintScale paintScale) {
113
114        ParamChecks.nullNotPermitted(dataset, "dataset");
115        ParamChecks.nullNotPermitted(paintScale, "paintScale");
116        int xCount = dataset.getXSampleCount();
117        int yCount = dataset.getYSampleCount();
118        BufferedImage image = new BufferedImage(xCount, yCount,
119                BufferedImage.TYPE_INT_ARGB);
120        Graphics2D g2 = image.createGraphics();
121        for (int xIndex = 0; xIndex < xCount; xIndex++) {
122            for (int yIndex = 0; yIndex < yCount; yIndex++) {
123                double z = dataset.getZValue(xIndex, yIndex);
124                Paint p = paintScale.getPaint(z);
125                g2.setPaint(p);
126                g2.fillRect(xIndex, yCount - yIndex - 1, 1, 1);
127            }
128        }
129        return image;
130    }
131
132}