src/org/tiefaces/components/websheet/chart/ChartHelper.java
private DefaultCategoryDataset createDataset(
			final ChartData chartData) {
		DefaultCategoryDataset dataset = new DefaultCategoryDataset();
		List<ParsedCell> categoryList = chartData.getCategoryList();
		for (ChartSeries chartSeries : chartData.getSeriesList()) {
			String seriesLabel = getParsedCellValue(
					chartSeries.getSeriesLabel());
			List<ParsedCell> valueList = chartSeries.getValueList();
			for (int i = 0; i < categoryList.size(); i++) {
				try {
					String sCategory = getParsedCellValue(
							categoryList.get(i));
					String sValue = getParsedCellValue(valueList.get(i));
					dataset.addValue(Double.parseDouble(sValue),
							seriesLabel, sCategory);
				} catch (Exception ex) {
					LOG.log(Level.FINE, "error in creatDataset : "
							+ ex.getLocalizedMessage(), ex);
				}
			}
		}
		return dataset;

	}
private DefaultCategoryDataset createDataset(
			final ChartData chartData) {
		DefaultCategoryDataset dataset = new DefaultCategoryDataset();
		List<ParsedCell> categoryList = chartData.getCategoryList();
		for (ChartSeries chartSeries : chartData.getSeriesList()) {
			String seriesLabel = getParsedCellValue(
					chartSeries.getSeriesLabel());
			List<ParsedCell> valueList = chartSeries.getValueList();
			for (int i = 0; i < categoryList.size(); i++) {
				try {
					String sCategory = getParsedCellValue(
							categoryList.get(i));
					String sValue = getParsedCellValue(valueList.get(i));
					dataset.addValue(Double.parseDouble(sValue),
							seriesLabel, sCategory);
				} catch (Exception ex) {
					LOG.log(Level.FINE, "error in creatDataset : "
							+ ex.getLocalizedMessage(), ex);
				}
			}
		}
		return dataset;

	}
create default category dataset for JfreeChart with giving chartData.

@param chartData
contain information gathered from excel chart object.
@return DefaultCategoryDataset for jfreechart.