public static String getSimplePieChart(Map dataSource, String objectName, HttpSession session)
      throws Throwable {
    DefaultPieDataset dataset = new DefaultPieDataset();

    Element chartObject =
        XMLHandler.getElementByAttribute(getChartObjectList(), "name", objectName);

    String title = chartObject.getAttributeValue("title");

    int width = Integer.parseInt(chartObject.getAttributeValue("width"));
    int height = Integer.parseInt(chartObject.getAttributeValue("height"));

    Element LabelKeys = chartObject.getChild("Labels");
    Element ValueKeys = chartObject.getChild("Values");

    String valueKey = ValueKeys.getText();
    String valueType = ValueKeys.getAttributeValue("type");
    List labelKeys = LabelKeys.getChildren("Label");
    String labelKey = LabelKeys.getText();

    if (valueType.equalsIgnoreCase("number")) {
      for (int i = 0; i < dataSource.size(); i++) {
        Map rec = (Map) dataSource.get("ROW" + i);
        Number value = (Number) rec.get(valueKey);
        String label;
        if (labelKeys.isEmpty()) {
          label = DataFilter.show(rec, labelKey);
        } else {
          label = ((Element) labelKeys.get(i)).getText();
        }
        dataset.setValue(label, value);
      }
    } else {
      for (int i = 0; i < dataSource.size(); i++) {
        Map rec = (Map) dataSource.get("ROW" + i);
        double value = (Double) rec.get(valueKey);
        String label;
        if (labelKeys.isEmpty()) {
          label = DataFilter.show(rec, labelKey);
        } else {
          label = ((Element) labelKeys.get(i)).getText();
        }
        dataset.setValue(label, value);
      }
    }

    JFreeChart chart =
        ChartFactory.createPieChart3D(
            title,
            dataset,
            chartObject.getAttribute("showLegend").getBooleanValue(),
            chartObject.getAttribute("showToolTips").getBooleanValue(),
            chartObject.getAttribute("urls").getBooleanValue());

    PiePlot3D pie3dplot = (PiePlot3D) chart.getPlot();

    float alpha = 0.7F;
    if (chartObject.getAttribute("alpha") != null) {
      alpha = chartObject.getAttribute("alpha").getFloatValue();
    }
    pie3dplot.setForegroundAlpha(alpha);

    return ServletUtilities.saveChartAsPNG(chart, width, height, null, session);
  }
 private static List getChartObjectList() {
   Element root = XMLHandler.openXML(CONFIGFILE);
   return root.getChildren("Object");
 }