KEYIN - The type of the input key.VALUEIN - The type of the input value.KEYOUT - The type of the output key.@InterfaceAudience.Public @InterfaceStability.Stable public abstract class TableReducer<KEYIN,VALUEIN,KEYOUT> extends org.apache.hadoop.mapreduce.Reducer<KEYIN,VALUEIN,KEYOUT,Mutation>
Reducer class to add the required key and
value input/output classes. While the input key and value as well as the
output key can be anything handed in from the previous map phase the output
value must be either a Put
or a Delete instance when
using the TableOutputFormat class.
This class is extended by IdentityTableReducer but can also be
subclassed to implement similar features or any custom code needed. It has
the advantage to enforce the output value to a specific basic type.
Reducer| Constructor and Description |
|---|
TableReducer() |
Copyright © 2007–2019 The Apache Software Foundation. All rights reserved.