private void registerAppleCollision(int previousX, int previousY) {
    changeAppleCoordinates();
    BodyPart newBodyPart = new BodyPart(snakeBody);
    if (bodyParts.size() == 0) {
      newBodyPart.updatePosition(previousX, previousY);
    } else {
      BodyPart lastBodyPart = bodyParts.get(bodyParts.size() - 1);
      newBodyPart.updatePosition(lastBodyPart.getX(), lastBodyPart.getY());
    }

    bodyParts.add(newBodyPart);
    System.out.printf("Now %d body parts", bodyParts.size());
  }