//                                                                            Variable
    //

    /** Array of search request parameter rewriters for modifying search parameters. */
    protected SearchRequestParamsRewriter[] searchRequestParamsRewriters = {};

    /** Jackson ObjectMapper for JSON serialization/deserialization. */
    protected ObjectMapper mapper = new ObjectMapper();;

    /**

        SearchRequestParams params = createMockSearchRequestParams();
        SearchHelper.SearchRequestParamsRewriter rewriter1 = p -> {
            ((MockSearchRequestParams) p).setQuery("rewritten1");
            return p;
        };
        SearchHelper.SearchRequestParamsRewriter rewriter2 = p -> {
            ((MockSearchRequestParams) p).setQuery("rewritten2");
            return p;
        };