What are the core methods of a Reducer in hadoop

The three core methods of a Reducer are:



setup(): this method is used for configuring various parameters like input data size, distributed cache.

public void setup (context)

reduce(): heart of the reducer always called once per key with the associated reduced task

public void reduce(Key, Value, context)

cleanup(): this method is called to clean temporary files, only once at the end of the task

public void cleanup (context)
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