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    Anshuman1991
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    Q1: What is the difference between old and new API?

    ANS:- The difference between old and new API are mentioned below:-

    OLD API

    *OLD API used Mapper & Reducer as Interface.
    *OLD API can still be found in org.apache.hadoop.mapred.
    *Controlling mappers by writing MapRunnable, but no equivalent exists for reducers.
    *Job Control was done through JobClient.
    *In old API both map and reduce outputs are named part-nnnnn.
    *In Old API, the reduce() method passes values as a java.lang.Iterator

    NEW API

    *New API used Mapper and Reducer as Class.
    *New API is in the org.apache.hadoop.mapreduce package.
    *New API allows both mappers and reducers to control the execution flow by overriding the run() method.
    *Job control is done through the JOBclass in New API.
    *In the new API map outputs are named part-m-nnnnn, and reduce outputs are named part-r-nnnnn.
    *In new API, the reduce() method passes values as a java.lang.Iterable

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