V- value type
public interface Reducer<V>
Reducerinterface for combining two values of the same type into a new value. In contrast to
Aggregatorthe result type must be the same as the input type.
The provided values can be either original values from input
KeyValue pair records or be a previously
computed result from
Reducer can be used to implement aggregation functions like sum, min, or max.
|Modifier and Type||Method and Description|
Aggregate the two given values into a single one.