@InterfaceAudience.Public
 @InterfaceStability.Stable
public interface ValueAggregatorDescriptor
Configuration
 object. Its main function is to generate a list of aggregation-id/value 
 pairs. An aggregation id encodes an aggregation type which is used to 
 guide the way to aggregate the value in the reduce/combiner phrase of an
 Aggregate based job. 
 The mapper in an Aggregate based map/reduce job may create one or more of
 ValueAggregatorDescriptor objects at configuration time. For each input
 key/value pair, the mapper will use those objects to create aggregation
 id/value pairs.| Modifier and Type | Field and Description | 
|---|---|
| static Text | ONE | 
| static String | TYPE_SEPARATOR | 
| Modifier and Type | Method and Description | 
|---|---|
| void | configure(Configuration conf)Configure the object | 
| ArrayList<Map.Entry<Text,Text>> | generateKeyValPairs(Object key,
                   Object val)Generate a list of aggregation-id/value pairs for 
 the given key/value pair. | 
static final String TYPE_SEPARATOR
static final Text ONE
ArrayList<Map.Entry<Text,Text>> generateKeyValPairs(Object key, Object val)
key - input keyval - input valuevoid configure(Configuration conf)
conf - a Configuration object that may contain the information 
          that can be used to configure the object.Copyright © 2023 Apache Software Foundation. All rights reserved.