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From Doug Cutting <cutt...@apache.org>
Subject Re: setMapOutputValueClass doesn't work
Date Mon, 24 Mar 2008 22:26:42 GMT
Chang Hu wrote:
> Code below, also attached.  I put this together from the word count 
> example. 

The problem is with your combiner.  When a combiner is specified, it 
generates the final map output, since combination is a map-side 
operation.  Your combiner takes <Text,IntWritable> generated by your 
mapper and generates <Text,Text> outputs, which would not be acceptable 
to your reducer, which accepts <Text,IntWritable> inputs.  Does that 
make sense?


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