JavaFX RadioButton handle selection change event within group of radio buttons

import javafx.application.Application;
import javafx.beans.value.ChangeListener;
import javafx.beans.value.ObservableValue;
import javafx.geometry.Pos;
import javafx.scene.Scene;
import javafx.scene.control.Label;
import javafx.scene.control.RadioButton;
import javafx.scene.control.Toggle;
import javafx.scene.control.ToggleGroup;
import javafx.scene.layout.FlowPane;
import javafx.stage.Stage;

public class Main extends Application {

  private Label response;

  public static void main(String[] args) {
    launch(args);//w  w  w  . j  av a 2s  .  co  m
  }

  public void start(Stage myStage) {
    myStage.setTitle("Demonstrate Radio Buttons");

    FlowPane rootNode = new FlowPane(10, 10);

    rootNode.setAlignment(Pos.CENTER);

    Scene myScene = new Scene(rootNode, 220, 120);

    myStage.setScene(myScene);

    response = new Label("");

    // Create the radio buttons.
    RadioButton rbOne = new RadioButton("One");
    RadioButton rbTwo = new RadioButton("Two");
    RadioButton rbThree = new RadioButton("Three");

    // Create a toggle group.
    ToggleGroup tg = new ToggleGroup();

    // Add each button to a toggle group.
    rbOne.setToggleGroup(tg);
    rbTwo.setToggleGroup(tg);
    rbThree.setToggleGroup(tg);

    // Handle action events for the radio buttons.
    rbOne.setOnAction(e -> {
      response.setText("Transport selected is train.");
    });

    rbTwo.setOnAction(e -> {
      response.setText("Transport selected is car.");
    });

    rbThree.setOnAction(e -> {
      response.setText("Transport selected is airplane.");
    });

    // Fire the event for the first selection.
    rbOne.fire();

    // Use a change listener to respond to a change of selection within
    // the group of radio buttons.
    tg.selectedToggleProperty().addListener(new ChangeListener<Toggle>() {
      public void changed(ObservableValue<? extends Toggle> changed, Toggle oldVal, Toggle newVal) {
        // Cast new to RadioButton.
        RadioButton rb = (RadioButton) newVal;
        // Display the selection.
        response.setText("Transport selected is " + rb.getText());
      }
    });

    // Add the label and buttons to the scene graph.
    rootNode.getChildren().addAll(rbOne, rbTwo, rbThree, response);

    myStage.show();
  }
}