code: protected FunctionScoreQueryBuilder regFunctionScoreQ(QueryBuilder queryBuilder, Collection<FilterFunctionBuilder> list) {
          FunctionScoreQueryBuilder functionScoreQuery =
                  QueryBuilders.functionScoreQuery(queryBuilder, list.toArray(new FilterFunctionBuilder[list.size()]));
          regQ(functionScoreQuery);
          return functionScoreQuery;
      }
docs: ========