import org.jfree.experimental.chart.plot.CombinedCategoryPlot; //导入依赖的package包/类
/**
 * Creates a chart.
 *
 * @return A chart.
 */
private static JFreeChart createChart() {

    CategoryDataset dataset1 = createDataset1();
    NumberAxis rangeAxis1 = new NumberAxis("Value");
    rangeAxis1.setStandardTickUnits(NumberAxis.createIntegerTickUnits());
    LineAndShapeRenderer renderer1 = new LineAndShapeRenderer();
    renderer1.setBaseToolTipGenerator(
            new StandardCategoryToolTipGenerator());
    CategoryPlot subplot1 = new CategoryPlot(dataset1, null, rangeAxis1,
            renderer1);
    subplot1.setDomainGridlinesVisible(true);

    CategoryDataset dataset2 = createDataset2();
    NumberAxis rangeAxis2 = new NumberAxis("Value");
    rangeAxis2.setStandardTickUnits(NumberAxis.createIntegerTickUnits());
    BarRenderer renderer2 = new BarRenderer();
    renderer2.setBaseToolTipGenerator(
            new StandardCategoryToolTipGenerator());
    CategoryPlot subplot2 = new CategoryPlot(dataset2, null, rangeAxis2,
            renderer2);
    subplot2.setDomainGridlinesVisible(true);

    CategoryAxis domainAxis = new CategoryAxis("Category");
    CombinedCategoryPlot plot = new CombinedCategoryPlot(
            domainAxis, new NumberAxis("Range"));
    plot.add(subplot1, 2);
    plot.add(subplot2, 1);

    JFreeChart result = new JFreeChart(
            "Combined Domain Category Plot Demo",
            new Font("SansSerif", Font.BOLD, 12), plot, true);
    return result;

}