default <T> T mapTo(ClickHouseRecord r, Class<T> objClass) {
        return mapTo(r, objClass, null);
    }
Maps a record to a user-defined object. By default, it's same as
{@code mapTo(r, objClass, null)}.

@param <T>      type of the user-defined object
@param r        non-null record
@param objClass non-null class of the user-defined object
@return non-null mapped object
clickhouse-data/src/main/java/com/clickhouse/data/ClickHouseRecordMapper.java