Java tutorial
/* =========================================================== * JFreeChart : a free chart library for the Java(tm) platform * =========================================================== * * (C) Copyright 2000-2004, by Object Refinery Limited and Contributors. * * Project Info: http://www.jfree.org/jfreechart/index.html * * This library is free software; you can redistribute it and/or modify it under the terms * of the GNU Lesser General Public License as published by the Free Software Foundation; * either version 2.1 of the License, or (at your option) any later version. * * This library is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; * without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. * See the GNU Lesser General Public License for more details. * * You should have received a copy of the GNU Lesser General Public License along with this * library; if not, write to the Free Software Foundation, Inc., 59 Temple Place, Suite 330, * Boston, MA 02111-1307, USA. * * [Java is a trademark or registered trademark of Sun Microsystems, Inc. * in the United States and other countries.] * * ------------------ * BarChartDemo3.java * ------------------ * (C) Copyright 2002-2004, by Object Refinery Limited and Contributors. * * Original Author: David Gilbert (for Object Refinery Limited); * Contributor(s): -; * * $Id: BarChartDemo3.java,v 1.15 2004/05/10 16:45:24 mungady Exp $ * * Changes * ------- * 22-Aug-2002 : Version 1 (DG); * 28-Jul-2003 : Updated custom renderer for API changes in 0.9.10 (DG); * 11-Nov-2003 : Renamed BarChartDemo3.java (DG); * */ package j2se.jfreechart.barchart; import java.awt.Color; import java.awt.Paint; import org.jfree.chart.ChartFactory; import org.jfree.chart.ChartPanel; import org.jfree.chart.JFreeChart; import org.jfree.chart.axis.NumberAxis; import org.jfree.chart.axis.ValueAxis; import org.jfree.chart.labels.ItemLabelAnchor; import org.jfree.chart.labels.ItemLabelPosition; import org.jfree.chart.plot.CategoryPlot; import org.jfree.chart.plot.PlotOrientation; import org.jfree.chart.renderer.category.BarRenderer; import org.jfree.chart.renderer.category.CategoryItemRenderer; import org.jfree.data.category.CategoryDataset; import org.jfree.data.general.DatasetUtilities; import org.jfree.ui.ApplicationFrame; import org.jfree.ui.RefineryUtilities; import org.jfree.ui.TextAnchor; /** * A bar chart that uses a custom renderer to display different colors within a series. * No legend is displayed because there is only one series but the colors are not consistent. * */ public class BarChartDemo3 extends ApplicationFrame { /** * A custom renderer that returns a different color for each item in a single series. */ class CustomRenderer extends BarRenderer { /** The colors. */ private Paint[] colors; /** * Creates a new renderer. * * @param colors the colors. */ public CustomRenderer(final Paint[] colors) { this.colors = colors; } /** * Returns the paint for an item. Overrides the default behaviour inherited from * AbstractSeriesRenderer. * * @param row the series. * @param column the category. * * @return The item color. */ public Paint getItemPaint(final int row, final int column) { return this.colors[column % this.colors.length]; } } /** * Creates a new demo. * * @param title the frame title. */ public BarChartDemo3(final String title) { super(title); final CategoryDataset dataset = createDataset(); final JFreeChart chart = createChart(dataset); final ChartPanel chartPanel = new ChartPanel(chart); chartPanel.setPreferredSize(new java.awt.Dimension(500, 270)); setContentPane(chartPanel); } /** * Creates a sample dataset. * * @return a sample dataset. */ private CategoryDataset createDataset() { final double[][] data = new double[][] { { 4.0, 3.0, -2.0, 3.0, 6.0 } }; return DatasetUtilities.createCategoryDataset("Series ", "Category ", data); } /** * Creates a sample chart. * * @param dataset the dataset. * * @return a sample chart. */ private JFreeChart createChart(final CategoryDataset dataset) { final JFreeChart chart = ChartFactory.createBarChart("Bar Chart Demo 3", // chart title "Category", // domain axis label "Value", // range axis label dataset, // data PlotOrientation.VERTICAL, // the plot orientation false, // include legend true, false); chart.setBackgroundPaint(Color.lightGray); // get a reference to the plot for further customisation... final CategoryPlot plot = chart.getCategoryPlot(); plot.setNoDataMessage("NO DATA!"); final CategoryItemRenderer renderer = new CustomRenderer(new Paint[] { Color.red, Color.blue, Color.green, Color.yellow, Color.orange, Color.cyan, Color.magenta, Color.blue }); // renderer.setLabelGenerator(new StandardCategoryLabelGenerator()); renderer.setItemLabelsVisible(true); final ItemLabelPosition p = new ItemLabelPosition(ItemLabelAnchor.CENTER, TextAnchor.CENTER, TextAnchor.CENTER, 45.0); renderer.setPositiveItemLabelPosition(p); plot.setRenderer(renderer); // change the margin at the top of the range axis... final ValueAxis rangeAxis = plot.getRangeAxis(); rangeAxis.setStandardTickUnits(NumberAxis.createIntegerTickUnits()); rangeAxis.setLowerMargin(0.15); rangeAxis.setUpperMargin(0.15); return chart; } // **************************************************************************** // * JFREECHART DEVELOPER GUIDE * // * The JFreeChart Developer Guide, written by David Gilbert, is available * // * to purchase from Object Refinery Limited: * // * * // * http://www.object-refinery.com/jfreechart/guide.html * // * * // * Sales are used to provide funding for the JFreeChart project - please * // * support us so that we can continue developing free software. * // **************************************************************************** /** * Starting point for the demonstration application. * * @param args ignored. */ public static void main(final String[] args) { final BarChartDemo3 demo = new BarChartDemo3("Bar Chart Demo 3"); demo.pack(); RefineryUtilities.centerFrameOnScreen(demo); demo.setVisible(true); } }