// Creates a user resource
  @Override
  public UserResource toResource(User user) {
    UserResource userResource = new UserResource();
    userResource.setUserId(user.getUserId());
    userResource.setUserName(user.getUserName());

    // HATEOAS link builder object
    Link link = linkTo(methodOn(UserController.class).getUser(user.getUserId())).withSelfRel();
    userResource.add(link.withSelfRel());

    return userResource;
  }