JavaFX 2.0: Full Screen scene

To make the scene occupy full screen, use the code:
Rectangle2D screenBounds = Screen.getPrimary().getVisualBounds();
Scene scene = new Scene(root, screenBounds.getWidth(), screenBounds.getHeight());

/*
* To change this template, choose Tools | Templates
* and open the template in the editor.
*/
package javafx_fullscreen;

import javafx.application.Application;
import javafx.event.ActionEvent;
import javafx.event.EventHandler;
import javafx.geometry.Rectangle2D;
import javafx.scene.Scene;
import javafx.scene.control.Button;
import javafx.scene.layout.StackPane;
import javafx.stage.Screen;
import javafx.stage.Stage;

/**
*
* @author erix7
*/
public class JavaFX_FullScreen extends Application {

 /**
  * @param args the command line arguments
  */
 public static void main(String[] args) {
     launch(args);
 }

 @Override
 public void start(Stage primaryStage) {
     primaryStage.setTitle("Hello World!");
     Button btn = new Button();
     btn.setText("Say 'Hello World'");
     btn.setOnAction(new EventHandler<ActionEvent>() {

         @Override
         public void handle(ActionEvent event) {
             System.out.println("Hello World!");
         }
     });
  
     StackPane root = new StackPane();

     //Make scene occupy full screen
     Rectangle2D screenBounds = Screen.getPrimary().getVisualBounds();
     Scene scene = new Scene(root, screenBounds.getWidth(), screenBounds.getHeight());
  
     root.getChildren().add(btn);
     primaryStage.setScene(scene);
     primaryStage.show();
 }
}