| Class | Description | 
|---|---|
| InverseMapper<K,V> | 
 A  
Mapper that swaps keys and values. | 
| MultithreadedMapper<K1,V1,K2,V2> | 
 Multithreaded implementation for @link org.apache.hadoop.mapreduce.Mapper. 
 | 
| RegexMapper<K> | 
 A  
Mapper that extracts text matching a regular expression. | 
| TokenCounterMapper | 
 Tokenize the input values and emit each word with a count of 1. 
 | 
| WrappedMapper<KEYIN,VALUEIN,KEYOUT,VALUEOUT> | 
 A  
Mapper which wraps a given one to allow custom 
 Mapper.Context implementations. | 
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