presto-main/src/main/java/io/prestosql/operator/aggregation/MaxDataSizeForStats.java/MaxDataSizeForStats/combine
class MaxDataSizeForStats:    @CombineFunction
    public static void combine(@AggregationState NullableLongState state, @AggregationState NullableLongState otherState)
    {
        update(state, otherState.getLong());
    }