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From rabbit_cheng <rabbit_ch...@126.com>
Subject how can I get the number of reducer in Map
Date Tue, 26 Jul 2011 09:08:40 GMT
In my map function, I  need to know the number of reducer, the code segment in my program like
this:
   JobConf job = new JobConf(driverClass.class);
    int numReducer=job.getNumReduceTasks();
but the function invocation job.getNumReduceTasks() always returns the value of "1". I have
tested many times: In driver function, I set the number of reducer to 2 using the following
statements:
    JobConf job =new JobConf(driverClass.class);
    job.setNumReduceTasks(2);
As a result, the reducers' output file number is 2, so I know the  statements above worked,
but what I get in map function is still to be "1".  How can I get the right number of reducer
in map function? thanks!

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