InverseMapper (Apache Hadoop Main 3.5.0 API)
Description: declaration: package: org.apache.hadoop.mapreduce.lib.map, class: InverseMapper

Package org.apache.hadoop.mapreduce.lib.map

# Class InverseMapper<K,V>

java.lang.Object
org.apache.hadoop.mapreduce.Mapper<K,V,V,K>
org.apache.hadoop.mapreduce.lib.map.InverseMapper<K,V>

@Public @Stable public class InverseMapper<K,V> extends Mapper<K,V,V,K>
A `Mapper` that swaps keys and values.

- ## Nested Class Summary

  ## Nested classes/interfaces inherited from class org.apache.hadoop.mapreduce.Mapper

  `org.apache.hadoop.mapreduce.Mapper.Context`

- ## Constructor Summary

  Constructors
  Constructor
  Description
  `InverseMapper()`

- ## Method Summary

  Modifier and Type
  Method
  Description
  `void`
  `map(K key, V value, Mapper<K,V,V,K>.org.apache.hadoop.mapreduce.Mapper.Context context)`
  The inverse function.

  ### Methods inherited from class org.apache.hadoop.mapreduce.Mapper

  `cleanup, run, setup`

  ### Methods inherited from class java.lang.Object

  `clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait`

- ## Constructor Details

  - ### InverseMapper

    public InverseMapper()

- ## Method Details

  - ### map

    public void map(K key, V value, Mapper<K,V,V,K>.org.apache.hadoop.mapreduce.Mapper.Context context) throws IOException, InterruptedException
    The inverse function. Input keys and values are swapped.
    Overrides:
      `map` in class `Mapper<K,V,V,K>`
    Throws:
      `IOException`
      `InterruptedException`