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From Christian Kunz <ck...@yahoo-inc.com>
Subject Re: IdentityReducer is called instead of my own
Date Wed, 02 Feb 2011 22:23:25 GMT
I don't know of a transition guide, but I found a tutorial based on the new api:

http://hadoop.apache.org/mapreduce/docs/current/mapred_tutorial.html

I did not use it, but it might be useful.

BTW, you could use the

@Override

annotation when overriding any method to let the compiler detect issues like yours.

-Christian

On Feb 2, 2011, at 2:06 PM, Marco Didonna wrote:

> On 02/02/2011 10:23 PM, Christian Kunz wrote:
>> Without seeing the source code of the reduce method of  the InvIndexReduce class
>> my best guess would be that the signature is incorrect. I saw this happen when migrating
from old to new api:
>> 
>> protected void reduce(KEYIN key, Iterable<VALUEIN> values, Context context)
>> 
>> (Iterable, not Iterator as in the old api)
>> 
>> -Christian
>> 
> 
> My God you're right...are you a sensitive or what :) :)? I am pretty new
> to Hadoop and I have studied the Tom White's book which is based on the
> old api (too bad)...I find quite difficult the migration to the new
> api...Is there a transition guide?
> 
> Thank you very very much...I was going to call an exorcist since there
> was no warning, no error whatsoever...
> 
> Marco
> 


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