问如何制作堆积条形图的边？

EN

    private static CategoryDataset createDataset()
{
    DefaultCategoryDataset defaultcategorydataset = new DefaultCategoryDataset();
    defaultcategorydataset.addValue(10D, "Series 1", "Jan");
    defaultcategorydataset.addValue(12D, "Series 1", "Feb");
    defaultcategorydataset.addValue(13D, "Series 1", "Mar");
    defaultcategorydataset.addValue(4D, "Series 2", "Jan");
    defaultcategorydataset.addValue(3D, "Series 2", "Feb");
    defaultcategorydataset.addValue(2D, "Series 2", "Mar");
    defaultcategorydataset.addValue(2D, "Series 3", "Jan");
    defaultcategorydataset.addValue(3D, "Series 3", "Feb");
    defaultcategorydataset.addValue(2D, "Series 3", "Mar");
    defaultcategorydataset.addValue(2D, "Series 4", "Jan");
    defaultcategorydataset.addValue(3D, "Series 4", "Feb");
    defaultcategorydataset.addValue(4D, "Series 4", "Mar");
    return defaultcategorydataset;
}

private static JFreeChart createChart(CategoryDataset categorydataset)
{
    JFreeChart jfreechart = ChartFactory.createStackedBarChart("Stacked Bar Chart Demo 3", "Category", "Value", categorydataset, PlotOrientation.VERTICAL, true, false, false);
    CategoryPlot categoryplot = (CategoryPlot)jfreechart.getPlot();
    ExtendedStackedBarRenderer extendedstackedbarrenderer = new ExtendedStackedBarRenderer();
    extendedstackedbarrenderer.setBaseItemLabelsVisible(true);
    extendedstackedbarrenderer.setBaseItemLabelGenerator(new StandardCategoryItemLabelGenerator());
    extendedstackedbarrenderer.setBaseToolTipGenerator(new StandardCategoryToolTipGenerator());
    categoryplot.setRenderer(extendedstackedbarrenderer);
    NumberAxis numberaxis = (NumberAxis)categoryplot.getRangeAxis();
    numberaxis.setStandardTickUnits(NumberAxis.createIntegerTickUnits());
    numberaxis.setLowerMargin(0.14999999999999999D);
    numberaxis.setUpperMargin(0.14999999999999999D);
    numberaxis.setNumberFormatOverride(NumberFormat.getPercentInstance());
    ChartUtilities.applyCurrentTheme(jfreechart);
    return jfreechart;
}