## Uses of Class
org.apache.hadoop.mapreduce.Mapper

Packages that use Mapper
org.apache.hadoop.examples: Hadoop example code.
org.apache.hadoop.mapreduce
org.apache.hadoop.mapreduce.lib.map

Uses of Mapper in org.apache.hadoop.examples

Subclasses of Mapper in org.apache.hadoop.examples
`static class` `SecondarySort.MapClass` Read two integers from each line and generate a key, value pair as ((left, right), right).
`static class` `WordCount.TokenizerMapper`

Uses of Mapper in org.apache.hadoop.mapreduce

Methods in org.apache.hadoop.mapreduce that return types with arguments of type Mapper
`Class<? extends Mapper<?,?,?,?>>` `JobContext.getMapperClass()` Get the `Mapper` class for the job.

Method parameters in org.apache.hadoop.mapreduce with type arguments of type Mapper
`void` `Job.setMapperClass(Class<? extends Mapper> cls)` Set the `Mapper` for the job.

Uses of Mapper in org.apache.hadoop.mapreduce.lib.map

Subclasses of Mapper in org.apache.hadoop.mapreduce.lib.map
`class` `InverseMapper<K,V>` A `Mapper` that swaps keys and values.
`class` `MultithreadedMapper<K1,V1,K2,V2>` Multithreaded implementation for @link org.apache.hadoop.mapreduce.Mapper.
`class` `TokenCounterMapper` Tokenize the input values and emit each word with a count of 1.

Methods in org.apache.hadoop.mapreduce.lib.map that return types with arguments of type Mapper

`static

`<K1,V1,K2,V2> Class<Mapper<K1,V1,K2,V2>>`

`

`MultithreadedMapper.getMapperClass(JobContext job)`
Get the application's mapper class.

Method parameters in org.apache.hadoop.mapreduce.lib.map with type arguments of type Mapper

`static

`<K1,V1,K2,V2> void`

`

`MultithreadedMapper.setMapperClass(Job job, Class<? extends Mapper<K1,V1,K2,V2>> cls)`
Set the application's mapper class.

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