Эффект появления/затухания в Java fx

Можно использовать анимацию

public void start(Stage stage) {
    Text msg = new Text("JavaFX animation is cool!");
    msg.setTextOrigin(VPos.TOP);
    msg.setFont(Font.font(24));
    Pane root = new Pane(msg);
    root.setPrefSize(500, 70);
    Scene scene = new Scene(root);
    stage.setScene(scene);
    stage.setTitle("Opacity");
    stage.show();
    /* Set up a Timeline animation */
    // Create the initial and final key frames
    KeyValue initKeyValue = new KeyValue(msg.opacityProperty(), 0.0);
    KeyFrame initFrame = new KeyFrame(Duration.ZERO, initKeyValue);
    KeyValue endKeyValue = new KeyValue(msg.opacityProperty(), 1.0);
    KeyFrame endFrame = new KeyFrame(Duration.seconds(3), endKeyValue);
    // Create a Timeline object
    Timeline timeline = new Timeline(initFrame, endFrame);
    // Let the animation run forever
    timeline.setCycleCount(Timeline.INDEFINITE);
    // Start the animation
    timeline.play();
}