public function feedDataTable()
    {
        if (!$this->isXmlHttpRequest()) {
            throw new \Exception('Only ajax call allowed.');
        }

        if (!$this->hasRequestParameter(self::PARAMETER_COLUMNS)) {
            throw new common_Exception('Parameter "'. self::PARAMETER_COLUMNS .'" missing');
        }

        $this->returnJson((new ResultsPayload($this->getExporterService()->getExporter()))->getPayload());
    }