public function create(UserInterface $user)
  {
    if($user == null || $user->getAuthIdentifier() == null) {
      return false;
    }

    $token = $this->generateAuthToken();
    $token->setAuthIdentifier( $user->getAuthIdentifier() );

    $t = new \DateTime;
    $insertData = array_merge($token->toArray(), array(
       'created_at' => $t, 'updated_at' => $t
    ));

    $this->db()->insert($insertData);

    return $token;
  }