private function getCurrentExporter()
    {
        if ($this->hasRequestParameter('exportHandler')) {
            $exportHandler = $_REQUEST['exportHandler'];//allow method "GET"
            if (class_exists($exportHandler)
                && in_array('tao_models_classes_export_ExportHandler', class_implements($exportHandler))
            ) {
                return new $exportHandler();
            } else {
                throw new common_Exception('Unknown or incompatible ExporterHandler: \'' . $exportHandler . '\'');
            }
        } else {
            return current($this->getAvailableExportHandlers());
        }
    }