public function __construct($message, $file_path, $params = array())
  {
    $this->_file_path = $file_path;

    $params['file_path'] = $file_path;

    parent::__construct($message, $params);
  }
  public function __construct($message, $driver_error = null, $additional_params = array())
  {
    if ($driver_error !== null)
    {
      $this->_driver_error = $driver_error;
      $additional_params['driver_error'] = $driver_error;
    }

    parent::__construct($message, $additional_params);
  }