}

    private void setupMockComponents() {
        // Mock SearchEngineClient
        SearchEngineClient mockSearchEngineClient = new SearchEngineClient() {
            @Override
            public long updateByQuery(String index,
                    java.util.function.Function<org.opensearch.action.search.SearchRequestBuilder, org.opensearch.action.search.SearchRequestBuilder> builder,

        final LanguageHelper languageHelper = ComponentUtil.getLanguageHelper();

        final StringBuilder resultBuf = new StringBuilder();

        try {
            final long count = searchEngineClient.updateByQuery(fessConfig.getIndexDocumentUpdateIndex(), option -> {
                if (queryBuilder != null) {
                    option.setQuery(queryBuilder);
                }

     * @param option  function to customize the search request
     * @param builder function to build update requests from search hits
     * @return the number of documents processed
     */
    public long updateByQuery(final String index, final Function<SearchRequestBuilder, SearchRequestBuilder> option,
            final BiFunction<UpdateRequestBuilder, SearchHit, UpdateRequestBuilder> builder) {