JavaFX MediaPlayer seek duration

import javafx.animation.KeyFrame;
import javafx.animation.Timeline;
import javafx.application.Application;
import javafx.geometry.Pos;
import javafx.scene.Scene;
import javafx.scene.control.TextField;
import javafx.scene.input.KeyCode;
import javafx.scene.layout.StackPane;
import javafx.scene.media.Media;
import javafx.scene.media.MediaPlayer;
import javafx.scene.text.Font;
import javafx.stage.Stage;
import javafx.util.Duration;

public class Main extends Application {
   protected TextField count = new TextField();
   protected Media media = new Media("your.mp3");
   protected MediaPlayer mediaPlayer = new MediaPlayer(media);
   protected Timeline animation;

   @Override/* w  ww .j ava  2s.  co  m*/
   public void start(Stage primaryStage) {
      // Set text field properties
      count.setAlignment(Pos.CENTER);
      count.setFont(Font.font(60));
      count.setPrefColumnCount(4);

      mediaPlayer.setCycleCount(MediaPlayer.INDEFINITE);

      // Create a pane
      StackPane pane = new StackPane(count);

      // Create animation for stopwatch
      animation = new Timeline(new KeyFrame(Duration.millis(1000), e -> run()));
      animation.setCycleCount(Timeline.INDEFINITE);

      count.setOnKeyPressed(e -> {
         if (e.getCode() == KeyCode.ENTER) {
            animation.play();
         }
      });

      // Create a scene and place it in the stage
      Scene scene = new Scene(pane);
      primaryStage.setTitle("java2s.com");
      primaryStage.setScene(scene);
      primaryStage.show();
   }

   /* Animate the stopwatch and controls mediaPlayer */
   private void run() {
      if (Integer.parseInt(count.getText()) > 0) {
         mediaPlayer.pause();
         mediaPlayer.seek(Duration.ZERO);
         count.setText(String.valueOf(Integer.parseInt(count.getText()) - 1));
      }
      if (count.getText().equals("0")) {
         animation.pause();
         mediaPlayer.play();
      }
   }
}