public function emptyIndexAction()
    {
        $siteHash = $this->selectedSite->getSiteHash();

        try {
            $affectedCores = [];
            $solrServers = $this->solrConnectionManager->getConnectionsBySite($this->selectedSite);
            foreach ($solrServers as $solrServer) {
                $writeService = $solrServer->getWriteService();
                /* @var $solrServer SolrConnection */
                $writeService->deleteByQuery('siteHash:' . $siteHash);
                $writeService->commit(false, false, false);
                $affectedCores[] = $writeService->getPrimaryEndpoint()->getCore();
            }
            $message = LocalizationUtility::translate('solr.backend.index_administration.index_emptied_all', 'Solr', [$this->selectedSite->getLabel(), implode(', ', $affectedCores)]);
            $this->addFlashMessage($message);
        } catch (\Exception $e) {
            $this->addFlashMessage(LocalizationUtility::translate('solr.backend.index_administration.error.on_empty_index', 'Solr', [$e->__toString()]), '', FlashMessage::ERROR);
        }

        $this->redirect('index');
    }