public function exportSynonymsAction($fileFormat = 'txt')
    {
        $coreAdmin = $this->selectedSolrCoreConnection->getAdminService();
        $synonyms = $coreAdmin->getSynonyms();
        return $this->exportFile(ManagedResourcesUtility::exportSynonymsToTxt($synonyms), 'synonyms', $fileFormat);
    }