如何製作Stacked Bar類型圖形的邊緣？

使系列上的邊緣很簡單，但是關於如何使圖2中顯示的圖形沒有找到任何示例。下面顯示的代碼生成圖1所示的圖形。我想找到一種方法來獲得圖2中顯示的圖形。如何製作Stacked Bar類型圖形的邊緣？

您有些人曾經遇到過這種需求嗎？有沒有簡單的方法來獲得結果？

非常感謝。

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; 
}

Figure 1 - Stacked Bar Chart Demo dorderless.