Steps to write a Custom Partitioner for a Hadoop MapReduce Job-
A new class must be created that extends the pre-defined Partitioner Class.
getPartition method of the Partitioner class must be overridden.
The custom partitioner to the job can be added as a config file in the wrapper which runs Hadoop MapReduce or the custom partitioner can be added to the job by using the set method of the partitioner class.
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