Error in Tooltip for javaFX Linechart - javafx

Question

I am using JavaFX LineChart. I am trying to set the tooltip on the linechart. I am getting error runtime error in event handle. What is wrong in the code?
public class ChartPlot
{
static LineChart <Number,Number> linechart;
static double[] xArray, yArray;
static ArrayList <Double> xList, yList;
public static XYChart.Series series;
public static LineChart linePlot(double[] x, double[] y) {
xArray = new double[x.length];
yArray = new double[y.length];
xArray = x;
yArray = y;
//Defining the x axis
final NumberAxis xAxis = new NumberAxis();
xAxis.setLabel("Wavelength");
//Defining the y axis
final NumberAxis yAxis = new NumberAxis();
yAxis.setLabel("Intensity");
//Creating the line chart
linechart = new LineChart <>(xAxis, yAxis);
linechart.getData().clear();
//Prepare XYChart.Series objects by setting data
series = new XYChart.Series();
//Setting the data to Line chart
for (int i = 0; i < xArray.length; i++) {
series.getData().add(new XYChart.Data(xArray[i], yArray[i]));
}
linechart.setCreateSymbols(false);
linechart.getData().add(series);
xAxis.setAutoRanging(true);
xAxis.setForceZeroInRange(false);
yAxis.setAutoRanging(true);
yAxis.setForceZeroInRange(false);
linechart.autosize();
linechart.applyCss();
String css = FXMLDocumentController.class.getResource("LSG.css").toExternalForm();
linechart.getStylesheets().add(css);
linechart.setLegendVisible(false);
for (XYChart.Series <Number, Number> s: linechart.getData()) {
for (XYChart.Data <Number, Number> d: s.getData()) {
Tooltip.install(d.getNode(), new Tooltip(
d.getXValue().toString() + "," + d.getYValue()));
//Adding Class on Hover or on click
d.getNode().addEventHandler(MouseEvent.MOUSE_CLICKED, new EventHandler < MouseEvent > () //----- This is the line I am getting error
{#Override
public void handle(MouseEvent event) {
System.out.println("X :" + d.getXValue() + " Y :" + d.getYValue());
}
});
}
}
return linechart;
}
}
I am using Open button to read a file and plot. While plotting I am trying to insert listener also to show the value on which I click.