Exception in thread "main" java.lang.NoClassDefFoundError: javafx/application/Application

AudioUtil.Song(System.getProperty("user.home") + "/data/music/test.mp3");
        AudioUtil.Play();
        frame = new JFrame(title);
        frame.setSize(width, height);
        frame.setBackground(Color.BLACK);
        frame.setLocationRelativeTo(null);
        frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
        frame.setVisible(true);
        frame.add(this, BorderLayout.CENTER);

public class AudioUtil extends Application {

    private static JFXPanel fxPanel;
    private static Media media;
    private static MediaPlayer mediaPlayer;