histogramdemo1.java

在软件开发中用来绘制各种图表的源码

/* -------------------
 * HistogramDemo1.java
 * -------------------
 * (C) Copyright 2004, by Object Refinery Limited.
 *
 */

package demo;

import java.io.IOException;
import java.util.Random;

import javax.swing.JPanel;

import org.jfree.chart.ChartFactory;
import org.jfree.chart.ChartPanel;
import org.jfree.chart.JFreeChart;
import org.jfree.chart.plot.PlotOrientation;
import org.jfree.chart.plot.XYPlot;
import org.jfree.chart.renderer.xy.XYBarRenderer;
import org.jfree.data.statistics.HistogramDataset;
import org.jfree.data.xy.IntervalXYDataset;
import org.jfree.ui.ApplicationFrame;
import org.jfree.ui.RefineryUtilities;

/**
 * A demo of the {@link HistogramDataset} class.
 */
public class HistogramDemo1 extends ApplicationFrame {

    /**
     * Creates a new demo.
     * 
     * @param title  the frame title.
     */
    public HistogramDemo1(String title) {
        super(title);    
        JPanel chartPanel = createDemoPanel();
        chartPanel.setPreferredSize(new java.awt.Dimension(500, 270));
        setContentPane(chartPanel);
    }
    
    /**
     * Creates a sample {@link HistogramDataset}.
     * 
     * @return the dataset.
     */
    private static IntervalXYDataset createDataset() {
        HistogramDataset dataset = new HistogramDataset();
        double[] values = new double[1000];
        Random generator = new Random(12345678L);
        for (int i = 0; i < 1000; i++) {
            values[i] = generator.nextGaussian() + 5;
        }
        dataset.addSeries("H1", values, 100, 2.0, 8.0);
        
        values = new double[1000];
        for (int i = 0; i < 1000; i++) {
            values[i] = generator.nextGaussian() + 7;
        }
        dataset.addSeries("H2", values, 100, 4.0, 10.0);
        return dataset;     
    }
    
    /**
     * Creates a chart.
     * 
     * @param dataset  a dataset.
     * 
     * @return The chart.
     */
    private static JFreeChart createChart(IntervalXYDataset dataset) {
        JFreeChart chart = ChartFactory.createHistogram(
            "Histogram Demo", 
            null, 
            null, 
            dataset, 
            PlotOrientation.VERTICAL, 
            true, 
            false, 
            false
        );
        XYPlot plot = (XYPlot) chart.getPlot();
        plot.setForegroundAlpha(0.85f);
        XYBarRenderer renderer = (XYBarRenderer) plot.getRenderer();
        renderer.setDrawBarOutline(false);
        return chart;
    }
        
    /**
     * Creates a panel for the demo (used by SuperDemo.java).
     * 
     * @return A panel.
     */
    public static JPanel createDemoPanel() {
        JFreeChart chart = createChart(createDataset());
        return new ChartPanel(chart);
    }
    
    /**
     * The starting point for the demo.
     * 
     * @param args  ignored.
     * 
     * @throws IOException  if there is a problem saving the file.
     */
    public static void main(String[] args) throws IOException {
        
        HistogramDemo1 demo = new HistogramDemo1("Histogram Demo 1");
        demo.pack();
        RefineryUtilities.centerFrameOnScreen(demo);
        demo.setVisible(true);
        
    }

}