NewDeviceController.java

package ui.controllers;

import javafx.event.ActionEvent;
import javafx.fxml.FXML;
import javafx.scene.Node;
import javafx.stage.Stage;
import ui.Controller;

@Controller
public class NewDeviceController {

    @FXML public void closeStage(ActionEvent event){
        Node source = (Node) event.getSource();
        Stage stage = (Stage) source.getScene().getWindow();
        stage.close();
    }
}