code: public XYSeries addSeries(
        String seriesName,
        List<?> xData,
        List<? extends Number> yData,
        List<? extends Number> errorBars) {
  
      DataType dataType = getDataType(xData);
      switch (dataType) {
        case Date:
          return addSeries(
              seriesName,
              Utils.getDoubleArrayFromDateList(xData),
              Utils.getDoubleArrayFromNumberList(yData),
              Utils.getDoubleArrayFromNumberList(errorBars),
              DataType.Date);
  
        default:
          return addSeries(
              seriesName,
              Utils.getDoubleArrayFromNumberList(xData),
              Utils.getDoubleArrayFromNumberList(yData),
              Utils.getDoubleArrayFromNumberList(errorBars),
              DataType.Number);
      }
    }
docs: Add a series for a X-Y type chart using Lists
  
  @param seriesName
  @param xData the X-Axis data
  @param yData the Y-Axis data
  @param errorBars the error bar data
  @return A Series object that you can set properties on