code: public static XYChart getChart(
        String chartTitle,
        String xTitle,
        String yTitle,
        String[] seriesNames,
        double[] xData,
        double[][] yData) {
  
      // Create Chart
      XYChart chart = new XYChart(WIDTH, HEIGHT);
  
      // Customize Chart
      chart.setTitle(chartTitle);
      chart.setXAxisTitle(xTitle);
      chart.setYAxisTitle(yTitle);
  
      // Series
      for (int i = 0; i < yData.length; i++) {
        XYSeries series;
        if (seriesNames != null) {
          series = chart.addSeries(seriesNames[i], xData, yData[i]);
        } else {
          chart.getStyler().setLegendVisible(false);
          series = chart.addSeries(" " + i, xData, yData[i]);
        }
        series.setMarker(SeriesMarkers.NONE);
      }
      return chart;
    }
docs: Creates a Chart with multiple Series for the same X-Axis data with default style
  
  @param chartTitle the Chart title
  @param xTitle The X-Axis title
  @param yTitle The Y-Axis title
  @param seriesNames An array of the name of the multiple series
  @param xData An array containing the X-Axis data
  @param yData An array of double arrays containing multiple Y-Axis data
  @return a Chart Object