## Uses of Class
org.apache.hadoop.mapred.MapReduceBase

Packages that use MapReduceBase
org.apache.hadoop.contrib.index.mapred
org.apache.hadoop.examples: Hadoop example code.
org.apache.hadoop.examples.dancing: This package is a distributed implementation of Knuth's dancing links algorithm that can run under Hadoop.
org.apache.hadoop.examples.terasort: This package consists of 3 map/reduce applications for Hadoop to compete in the annual terabyte sort competition.
org.apache.hadoop.mapred.lib: Library of generally useful mappers, reducers, and partitioners.

Uses of MapReduceBase in org.apache.hadoop.contrib.index.mapred

Subclasses of MapReduceBase in org.apache.hadoop.contrib.index.mapred
`class` `IndexUpdateCombiner` This combiner combines multiple intermediate forms into one intermediate form.
`class` `IndexUpdateMapper<K extends WritableComparable,V extends Writable>` This class applies local analysis on a key-value pair and then convert the result docid-operation pair to a shard-and-intermediate form pair.
`class` `IndexUpdateReducer` This reducer applies to a shard the changes for it.

Uses of MapReduceBase in org.apache.hadoop.examples

Subclasses of MapReduceBase in org.apache.hadoop.examples
`static class` `MultiFileWordCount.MapClass` This Mapper is similar to the one in `MultiFileWordCount.MapClass`.
`static class` `PiEstimator.PiMapper` Mapper class for Pi estimation.
`static class` `PiEstimator.PiReducer` Reducer class for Pi estimation.

Uses of MapReduceBase in org.apache.hadoop.examples.dancing

Subclasses of MapReduceBase in org.apache.hadoop.examples.dancing
`static class` `DistributedPentomino.PentMap` Each map takes a line, which represents a prefix move and finds all of the solutions that start with that prefix.

Uses of MapReduceBase in org.apache.hadoop.examples.terasort

Subclasses of MapReduceBase in org.apache.hadoop.examples.terasort
`static class` `TeraGen.SortGenMapper` The Mapper class that given a row number, will generate the appropriate output line.

Uses of MapReduceBase in org.apache.hadoop.mapred.lib

Subclasses of MapReduceBase in org.apache.hadoop.mapred.lib
`class` `IdentityMapper<K,V>` Implements the identity function, mapping inputs directly to outputs.
`class` `IdentityReducer<K,V>` Performs no reduction, writing all input values directly to the output.
`class` `InverseMapper<K,V>` A `Mapper` that swaps keys and values.
`class` `LongSumReducer<K>` A `Reducer` that sums long values.
`class` `RegexMapper<K>` A `Mapper` that extracts text matching a regular expression.
`class` `TokenCountMapper<K>` A `Mapper` that maps text values into <token,freq> pairs.

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