public function initializeIndexQueueAction()
    {
        $initializedIndexingConfigurations = [];

        $indexingConfigurationsToInitialize = GeneralUtility::_POST('tx_solr-index-queue-initialization');
        if ((!empty($indexingConfigurationsToInitialize)) && (is_array($indexingConfigurationsToInitialize))) {
            // initialize selected indexing configuration
            $initializedIndexingConfigurations = $this->indexQueue->getInitializationService()->initializeBySiteAndIndexConfigurations($this->selectedSite, $indexingConfigurationsToInitialize);
        } else {
            $messageLabel = 'solr.backend.index_queue_module.flashmessage.initialize.no_selection';
            $titleLabel = 'solr.backend.index_queue_module.flashmessage.not_initialized.title';
            $this->addFlashMessage(
                LocalizationUtility::translate($messageLabel, 'Solr'),
                LocalizationUtility::translate($titleLabel, 'Solr'),
                FlashMessage::WARNING
            );
        }
        $messagesForConfigurations = [];
        foreach (array_keys($initializedIndexingConfigurations) as $indexingConfigurationName) {
            $itemCount = $this->indexQueue->getStatisticsBySite($this->selectedSite, $indexingConfigurationName)->getTotalCount();
            $messagesForConfigurations[] = $indexingConfigurationName . ' (' . $itemCount . ' records)';
        }

        if (!empty($initializedIndexingConfigurations)) {
            $messageLabel = 'solr.backend.index_queue_module.flashmessage.initialize.success';
            $titleLabel = 'solr.backend.index_queue_module.flashmessage.initialize.title';
            $this->addFlashMessage(
                LocalizationUtility::translate($messageLabel, 'Solr', [implode(', ', $messagesForConfigurations)]),
                LocalizationUtility::translate($titleLabel, 'Solr'),
                FlashMessage::OK
            );
        }

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