/**
  * _matchCredentials 
  * 
  * @param mixed $token    The token to match 
  * @param mixed $authInfo The authentication info to match the token with
  *
  * @access private
  * @return void
  * @throws Exception
  */
 private function _matchCredentials($token, $authInfo)
 {
     $tokenCred = $token->getCredentials();
     $authCred = $authInfo->getCredentials();
     // TODO: Extract validation logic to CredentialsMatcher.
     if (PasswordUtils::check($tokenCred, $authCred) !== 'OK') {
         throw new Exception('Incorrect Credentials');
     }
 }