LineChartData lineChartData =
chart.getChartDataFactory().createLineChartData();
ChartDataSource<String> xs = DataSources.fromStringCellRange(sheet, CellRangeAddress.valueOf("A1:J1"));
ChartDataSource<Number> ys = DataSources.fromNumericCellRange(sheet, CellRangeAddress.valueOf("A2:J2"));
LineChartSeries series = lineChartData.addSeries(xs, ys);
assertNotNull(series);
assertEquals(1, lineChartData.getSeries().size());
assertTrue(lineChartData.getSeries().contains(series));